Series comparison

-[PULL v2 00/30] Block patches
+[PULL v2 00/28] Block patches
-The following changes since commit 2387df497b4b4bcf754eb7398edca82889e2ef54:
+The following changes since commit ac793156f650ae2d77834932d72224175ee69086:
-  Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2020-10-10' into staging (2020-10-12 11:29:42 +0100)
+  Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20201020-1' into staging (2020-10-20 21:11:35 +0100)
 are available in the Git repository at:
   https://gitlab.com/stefanha/qemu.git tags/block-pull-request
-for you to fetch changes up to 3664ec6bbe236126b79d251d4037889e7181ab55:
+for you to fetch changes up to 32a3fd65e7e3551337fd26bfc0e2f899d70c028c:
-  iotests: add commit top->base cases to 274 (2020-10-12 16:47:58 +0100)
+  iotests: add commit top->base cases to 274 (2020-10-22 09:55:39 +0100)
 ----------------------------------------------------------------
 Pull request
 v2:
- * Rebase and resolve conflict with commit 029a88c9a7e3 ("qemu-nbd: Honor
+ * Fix format string issues on 32-bit hosts [Peter]
-   SIGINT and SIGHUP") [Peter]
+ * Fix qemu-nbd.c CONFIG_POSIX ifdef issue [Eric]
  * Fix missing eventfd.h header on macOS [Peter]
  * Drop unreliable vhost-user-blk test (will send a new patch when ready) [Peter]
 This pull request contains the vhost-user-blk server by Coiby Xu along with my
 additions, block/nvme.c alignment and hardware error statistics by Philippe
 Mathieu-Daudé, and bdrv_co_block_status_above() fixes by Vladimir
 Sementsov-Ogievskiy.
 ----------------------------------------------------------------
-Coiby Xu (7):
+Coiby Xu (6):
   libvhost-user: Allow vu_message_read to be replaced
   libvhost-user: remove watch for kick_fd when de-initialize vu-dev
   util/vhost-user-server: generic vhost user server
   block: move logical block size check function to a common utility
     function
   block/export: vhost-user block device backend server
-  test: new qTest case to test the vhost-user-blk-server
   MAINTAINERS: Add vhost-user block device backend server maintainer
 Philippe Mathieu-Daudé (1):
   block/nvme: Add driver statistics for access alignment and hw errors
-Stefan Hajnoczi (17):
+Stefan Hajnoczi (16):
   util/vhost-user-server: s/fileds/fields/ typo fix
   util/vhost-user-server: drop unnecessary QOM cast
   util/vhost-user-server: drop unnecessary watch deletion
   block/export: consolidate request structs into VuBlockReq
   util/vhost-user-server: drop unused DevicePanicNotifier
 ...
   util/vhost-user-server: use static library in meson.build
   qemu-storage-daemon: avoid compiling blockdev_ss twice
   block: move block exports to libblockdev
   block/export: add iothread and fixed-iothread options
   block/export: add vhost-user-blk multi-queue support
-  tests/qtest: add multi-queue test case to vhost-user-blk-test
 Vladimir Sementsov-Ogievskiy (5):
   block/io: fix bdrv_co_block_status_above
   block/io: bdrv_common_block_status_above: support include_base
   block/io: bdrv_common_block_status_above: support bs == base
   block/io: fix bdrv_is_allocated_above
   iotests: add commit top->base cases to 274
- MAINTAINERS                                |  10 +
+ MAINTAINERS                                |   9 +
  qapi/block-core.json                       |  24 +-
  qapi/block-export.json                     |  36 +-
  block/coroutines.h                         |   2 +
  block/export/vhost-user-blk-server.h       |  19 +
  contrib/libvhost-user/libvhost-user.h      |  21 +
- include/qemu/vhost-user-server.h           |  65 ++
+ include/qemu/vhost-user-server.h           |  65 +++
  tests/qtest/libqos/libqtest.h              |  17 +
  tests/qtest/libqos/vhost-user-blk.h        |  48 ++
  util/block-helpers.h                       |  19 +
  block/export/export.c                      |  37 +-
- block/export/vhost-user-blk-server.c       | 431 +++++++++++
+ block/export/vhost-user-blk-server.c       | 431 ++++++++++++++++++++
- block/io.c                                 | 132 ++--
+ block/io.c                                 | 132 +++---
- block/nvme.c                               |  27 +
+ block/nvme.c                               |  27 ++
  block/qcow2.c                              |  16 +-
  contrib/libvhost-user/libvhost-user-glib.c |   2 +-
  contrib/libvhost-user/libvhost-user.c      |  15 +-
  hw/core/qdev-properties-system.c           |  31 +-
  nbd/server.c                               |   2 -
- qemu-nbd.c                                 |  25 +-
+ qemu-nbd.c                                 |  21 +-
  softmmu/vl.c                               |   4 +
  stubs/blk-exp-close-all.c                  |   7 +
- tests/qtest/libqos/vhost-user-blk.c        | 129 ++++
- tests/qtest/libqtest.c                     |  36 +-
- tests/qtest/vhost-user-blk-test.c          | 822 +++++++++++++++++++++
  tests/vhost-user-bridge.c                  |   2 +
  tools/virtiofsd/fuse_virtio.c              |   4 +-
- util/block-helpers.c                       |  46 ++
+ util/block-helpers.c                       |  46 +++
- util/vhost-user-server.c                   | 446 +++++++++++
+ util/vhost-user-server.c                   | 446 +++++++++++++++++++++
  block/export/meson.build                   |   3 +-
  contrib/libvhost-user/meson.build          |   1 +
  meson.build                                |  22 +-
  nbd/meson.build                            |   2 +
  storage-daemon/meson.build                 |   3 +-
  stubs/meson.build                          |   1 +
  tests/qemu-iotests/274                     |  20 +
- tests/qemu-iotests/274.out                 |  68 ++
+ tests/qemu-iotests/274.out                 |  68 ++++
  tests/qtest/libqos/meson.build             |   1 +
  tests/qtest/meson.build                    |   4 +-
  util/meson.build                           |   4 +
-files changed, 2476 insertions(+), 128 deletions(-)
+files changed, 1420 insertions(+), 122 deletions(-)
  create mode 100644 block/export/vhost-user-blk-server.h
  create mode 100644 include/qemu/vhost-user-server.h
- create mode 100644 tests/qtest/libqos/vhost-user-blk.h
  create mode 100644 util/block-helpers.h
  create mode 100644 block/export/vhost-user-blk-server.c
  create mode 100644 stubs/blk-exp-close-all.c
- create mode 100644 tests/qtest/libqos/vhost-user-blk.c
- create mode 100644 tests/qtest/vhost-user-blk-test.c
  create mode 100644 util/block-helpers.c
  create mode 100644 util/vhost-user-server.c
 --
 .26.2

-[PULL v2 01/30] block/nvme: Add driver statistics for access alignment and hw errors
+[PULL v2 01/28] block/nvme: Add driver statistics for access alignment and hw errors
 From: Philippe Mathieu-Daudé <philmd@redhat.com>
 Keep statistics of some hardware errors, and number of
 aligned/unaligned I/O accesses.
 QMP example booting a full RHEL 8.3 aarch64 guest:
 { "execute": "query-blockstats" }
 {
     "return": [
         {
             "device": "",
             "node-name": "drive0",
             "stats": {
                 "flush_total_time_ns": 6026948,
                 "wr_highest_offset": 3383991230464,
                 "wr_total_time_ns": 807450995,
                 "failed_wr_operations": 0,
                 "failed_rd_operations": 0,
                 "wr_merged": 3,
                 "wr_bytes": 50133504,
                 "failed_unmap_operations": 0,
                 "failed_flush_operations": 0,
                 "account_invalid": false,
                 "rd_total_time_ns": 1846979900,
                 "flush_operations": 130,
                 "wr_operations": 659,
                 "rd_merged": 1192,
                 "rd_bytes": 218244096,
                 "account_failed": false,
                 "idle_time_ns": 2678641497,
                 "rd_operations": 7406,
             },
             "driver-specific": {
                 "driver": "nvme",
                 "completion-errors": 0,
                 "unaligned-accesses": 2959,
                 "aligned-accesses": 4477
             },
             "qdev": "/machine/peripheral-anon/device[0]/virtio-backend"
         }
     ]
 }
 Suggested-by: Stefan Hajnoczi <stefanha@gmail.com>
 Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
 Acked-by: Markus Armbruster <armbru@redhat.com>
 Message-id: 20201001162939.1567915-1-philmd@redhat.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  qapi/block-core.json | 24 +++++++++++++++++++++++-
  block/nvme.c         | 27 +++++++++++++++++++++++++++
 files changed, 50 insertions(+), 1 deletion(-)
 diff --git a/qapi/block-core.json b/qapi/block-core.json
 index XXXXXXX..XXXXXXX 100644
 --- a/qapi/block-core.json
 +++ b/qapi/block-core.json
 @@ -XXX,XX +XXX,XX @@
        'discard-nb-failed': 'uint64',
        'discard-bytes-ok': 'uint64' } }
 +##
 +# @BlockStatsSpecificNvme:
 +#
 +# NVMe driver statistics
 +#
 +# @completion-errors: The number of completion errors.
 +#
 +# @aligned-accesses: The number of aligned accesses performed by
 +#                    the driver.
 +#
 +# @unaligned-accesses: The number of unaligned accesses performed by
 +#                      the driver.
 +#
 +# Since: 5.2
 +##
 +{ 'struct': 'BlockStatsSpecificNvme',
 +  'data': {
 +      'completion-errors': 'uint64',
 +      'aligned-accesses': 'uint64',
 +      'unaligned-accesses': 'uint64' } }
 +
  ##
  # @BlockStatsSpecific:
  #
 @@ -XXX,XX +XXX,XX @@
    'discriminator': 'driver',
    'data': {
        'file': 'BlockStatsSpecificFile',
 -      'host_device': 'BlockStatsSpecificFile' } }
 +      'host_device': 'BlockStatsSpecificFile',
 +      'nvme': 'BlockStatsSpecificNvme' } }
  ##
  # @BlockStats:
 diff --git a/block/nvme.c b/block/nvme.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/nvme.c
 +++ b/block/nvme.c
 @@ -XXX,XX +XXX,XX @@ struct BDRVNVMeState {
      /* PCI address (required for nvme_refresh_filename()) */
      char *device;
 +
 +    struct {
 +        uint64_t completion_errors;
 +        uint64_t aligned_accesses;
 +        uint64_t unaligned_accesses;
 +    } stats;
  };
  #define NVME_BLOCK_OPT_DEVICE "device"
 @@ -XXX,XX +XXX,XX @@ static bool nvme_process_completion(NVMeQueuePair *q)
              break;
          }
          ret = nvme_translate_error(c);
 +        if (ret) {
 +            s->stats.completion_errors++;
 +        }
          q->cq.head = (q->cq.head + 1) % NVME_QUEUE_SIZE;
          if (!q->cq.head) {
              q->cq_phase = !q->cq_phase;
 @@ -XXX,XX +XXX,XX @@ static int nvme_co_prw(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
      assert(QEMU_IS_ALIGNED(bytes, s->page_size));
      assert(bytes <= s->max_transfer);
      if (nvme_qiov_aligned(bs, qiov)) {
 +        s->stats.aligned_accesses++;
          return nvme_co_prw_aligned(bs, offset, bytes, qiov, is_write, flags);
      }
 +    s->stats.unaligned_accesses++;
      trace_nvme_prw_buffered(s, offset, bytes, qiov->niov, is_write);
      buf = qemu_try_memalign(s->page_size, bytes);
 @@ -XXX,XX +XXX,XX @@ static void nvme_unregister_buf(BlockDriverState *bs, void *host)
      qemu_vfio_dma_unmap(s->vfio, host);
  }
 +static BlockStatsSpecific *nvme_get_specific_stats(BlockDriverState *bs)
 +{
 +    BlockStatsSpecific *stats = g_new(BlockStatsSpecific, 1);
 +    BDRVNVMeState *s = bs->opaque;
 +
 +    stats->driver = BLOCKDEV_DRIVER_NVME;
 +    stats->u.nvme = (BlockStatsSpecificNvme) {
 +        .completion_errors = s->stats.completion_errors,
 +        .aligned_accesses = s->stats.aligned_accesses,
 +        .unaligned_accesses = s->stats.unaligned_accesses,
 +    };
 +
 +    return stats;
 +}
 +
  static const char *const nvme_strong_runtime_opts[] = {
      NVME_BLOCK_OPT_DEVICE,
      NVME_BLOCK_OPT_NAMESPACE,
 @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_nvme = {
      .bdrv_refresh_filename    = nvme_refresh_filename,
      .bdrv_refresh_limits      = nvme_refresh_limits,
      .strong_runtime_opts      = nvme_strong_runtime_opts,
 +    .bdrv_get_specific_stats  = nvme_get_specific_stats,
      .bdrv_detach_aio_context  = nvme_detach_aio_context,
      .bdrv_attach_aio_context  = nvme_attach_aio_context,
 --
 .26.2

-[PULL v2 02/30] libvhost-user: Allow vu_message_read to be replaced
+[PULL v2 02/28] libvhost-user: Allow vu_message_read to be replaced
 From: Coiby Xu <coiby.xu@gmail.com>
 Allow vu_message_read to be replaced by one which will make use of the
 QIOChannel functions. Thus reading vhost-user message won't stall the
 guest. For slave channel, we still use the default vu_message_read.
 Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
 Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
 Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
 Message-id: 20200918080912.321299-2-coiby.xu@gmail.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  contrib/libvhost-user/libvhost-user.h      | 21 +++++++++++++++++++++
  contrib/libvhost-user/libvhost-user-glib.c |  2 +-
  contrib/libvhost-user/libvhost-user.c      | 14 +++++++-------
  tests/vhost-user-bridge.c                  |  2 ++
  tools/virtiofsd/fuse_virtio.c              |  4 ++--
 files changed, 33 insertions(+), 10 deletions(-)
 diff --git a/contrib/libvhost-user/libvhost-user.h b/contrib/libvhost-user/libvhost-user.h
 index XXXXXXX..XXXXXXX 100644
 --- a/contrib/libvhost-user/libvhost-user.h
 +++ b/contrib/libvhost-user/libvhost-user.h
 @@ -XXX,XX +XXX,XX @@
   */
  #define VHOST_USER_MAX_RAM_SLOTS 32
 +#define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64)
 +
  typedef enum VhostSetConfigType {
      VHOST_SET_CONFIG_TYPE_MASTER = 0,
      VHOST_SET_CONFIG_TYPE_MIGRATION = 1,
 @@ -XXX,XX +XXX,XX @@ typedef uint64_t (*vu_get_features_cb) (VuDev *dev);
  typedef void (*vu_set_features_cb) (VuDev *dev, uint64_t features);
  typedef int (*vu_process_msg_cb) (VuDev *dev, VhostUserMsg *vmsg,
                                    int *do_reply);
 +typedef bool (*vu_read_msg_cb) (VuDev *dev, int sock, VhostUserMsg *vmsg);
  typedef void (*vu_queue_set_started_cb) (VuDev *dev, int qidx, bool started);
  typedef bool (*vu_queue_is_processed_in_order_cb) (VuDev *dev, int qidx);
  typedef int (*vu_get_config_cb) (VuDev *dev, uint8_t *config, uint32_t len);
 @@ -XXX,XX +XXX,XX @@ struct VuDev {
      bool broken;
      uint16_t max_queues;
 +    /* @read_msg: custom method to read vhost-user message
 +     *
 +     * Read data from vhost_user socket fd and fill up
 +     * the passed VhostUserMsg *vmsg struct.
 +     *
 +     * If reading fails, it should close the received set of file
 +     * descriptors as socket message's auxiliary data.
 +     *
 +     * For the details, please refer to vu_message_read in libvhost-user.c
 +     * which will be used by default if not custom method is provided when
 +     * calling vu_init
 +     *
 +     * Returns: true if vhost-user message successfully received,
 +     *          otherwise return false.
 +     *
 +     */
 +    vu_read_msg_cb read_msg;
      /* @set_watch: add or update the given fd to the watch set,
       * call cb when condition is met */
      vu_set_watch_cb set_watch;
 @@ -XXX,XX +XXX,XX @@ bool vu_init(VuDev *dev,
               uint16_t max_queues,
               int socket,
               vu_panic_cb panic,
 +             vu_read_msg_cb read_msg,
               vu_set_watch_cb set_watch,
               vu_remove_watch_cb remove_watch,
               const VuDevIface *iface);
 diff --git a/contrib/libvhost-user/libvhost-user-glib.c b/contrib/libvhost-user/libvhost-user-glib.c
 index XXXXXXX..XXXXXXX 100644
 --- a/contrib/libvhost-user/libvhost-user-glib.c
 +++ b/contrib/libvhost-user/libvhost-user-glib.c
 @@ -XXX,XX +XXX,XX @@ vug_init(VugDev *dev, uint16_t max_queues, int socket,
      g_assert(dev);
      g_assert(iface);
 -    if (!vu_init(&dev->parent, max_queues, socket, panic, set_watch,
 +    if (!vu_init(&dev->parent, max_queues, socket, panic, NULL, set_watch,
                   remove_watch, iface)) {
          return false;
      }
 diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c
 index XXXXXXX..XXXXXXX 100644
 --- a/contrib/libvhost-user/libvhost-user.c
 +++ b/contrib/libvhost-user/libvhost-user.c
 @@ -XXX,XX +XXX,XX @@
  /* The version of inflight buffer */
  #define INFLIGHT_VERSION 1
 -#define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64)
 -
  /* The version of the protocol we support */
  #define VHOST_USER_VERSION 1
  #define LIBVHOST_USER_DEBUG 0
 @@ -XXX,XX +XXX,XX @@ have_userfault(void)
  }
  static bool
 -vu_message_read(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
 +vu_message_read_default(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
  {
      char control[CMSG_SPACE(VHOST_MEMORY_BASELINE_NREGIONS * sizeof(int))] = {};
      struct iovec iov = {
 @@ -XXX,XX +XXX,XX @@ vu_process_message_reply(VuDev *dev, const VhostUserMsg *vmsg)
          goto out;
      }
 -    if (!vu_message_read(dev, dev->slave_fd, &msg_reply)) {
 +    if (!vu_message_read_default(dev, dev->slave_fd, &msg_reply)) {
          goto out;
      }
 @@ -XXX,XX +XXX,XX @@ vu_set_mem_table_exec_postcopy(VuDev *dev, VhostUserMsg *vmsg)
      /* Wait for QEMU to confirm that it's registered the handler for the
       * faults.
       */
 -    if (!vu_message_read(dev, dev->sock, vmsg) ||
 +    if (!dev->read_msg(dev, dev->sock, vmsg) ||
          vmsg->size != sizeof(vmsg->payload.u64) ||
          vmsg->payload.u64 != 0) {
          vu_panic(dev, "failed to receive valid ack for postcopy set-mem-table");
 @@ -XXX,XX +XXX,XX @@ vu_dispatch(VuDev *dev)
      int reply_requested;
      bool need_reply, success = false;
 -    if (!vu_message_read(dev, dev->sock, &vmsg)) {
 +    if (!dev->read_msg(dev, dev->sock, &vmsg)) {
          goto end;
      }
 @@ -XXX,XX +XXX,XX @@ vu_init(VuDev *dev,
          uint16_t max_queues,
          int socket,
          vu_panic_cb panic,
 +        vu_read_msg_cb read_msg,
          vu_set_watch_cb set_watch,
          vu_remove_watch_cb remove_watch,
          const VuDevIface *iface)
 @@ -XXX,XX +XXX,XX @@ vu_init(VuDev *dev,
      dev->sock = socket;
      dev->panic = panic;
 +    dev->read_msg = read_msg ? read_msg : vu_message_read_default;
      dev->set_watch = set_watch;
      dev->remove_watch = remove_watch;
      dev->iface = iface;
 @@ -XXX,XX +XXX,XX @@ static void _vu_queue_notify(VuDev *dev, VuVirtq *vq, bool sync)
          vu_message_write(dev, dev->slave_fd, &vmsg);
          if (ack) {
 -            vu_message_read(dev, dev->slave_fd, &vmsg);
 +            vu_message_read_default(dev, dev->slave_fd, &vmsg);
          }
          return;
      }
 diff --git a/tests/vhost-user-bridge.c b/tests/vhost-user-bridge.c
 index XXXXXXX..XXXXXXX 100644
 --- a/tests/vhost-user-bridge.c
 +++ b/tests/vhost-user-bridge.c
 @@ -XXX,XX +XXX,XX @@ vubr_accept_cb(int sock, void *ctx)
                   VHOST_USER_BRIDGE_MAX_QUEUES,
                   conn_fd,
                   vubr_panic,
 +                 NULL,
                   vubr_set_watch,
                   vubr_remove_watch,
                   &vuiface)) {
 @@ -XXX,XX +XXX,XX @@ vubr_new(const char *path, bool client)
                       VHOST_USER_BRIDGE_MAX_QUEUES,
                       dev->sock,
                       vubr_panic,
 +                     NULL,
                       vubr_set_watch,
                       vubr_remove_watch,
                       &vuiface)) {
 diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
 index XXXXXXX..XXXXXXX 100644
 --- a/tools/virtiofsd/fuse_virtio.c
 +++ b/tools/virtiofsd/fuse_virtio.c
 @@ -XXX,XX +XXX,XX @@ int virtio_session_mount(struct fuse_session *se)
      se->vu_socketfd = data_sock;
      se->virtio_dev->se = se;
      pthread_rwlock_init(&se->virtio_dev->vu_dispatch_rwlock, NULL);
 -    vu_init(&se->virtio_dev->dev, 2, se->vu_socketfd, fv_panic, fv_set_watch,
 -            fv_remove_watch, &fv_iface);
 +    vu_init(&se->virtio_dev->dev, 2, se->vu_socketfd, fv_panic, NULL,
 +            fv_set_watch, fv_remove_watch, &fv_iface);
      return 0;
  }
 --
 .26.2

-[PULL v2 03/30] libvhost-user: remove watch for kick_fd when de-initialize vu-dev
+[PULL v2 03/28] libvhost-user: remove watch for kick_fd when de-initialize vu-dev
 From: Coiby Xu <coiby.xu@gmail.com>
 When the client is running in gdb and quit command is run in gdb,
 QEMU will still dispatch the event which will cause segment fault in
 the callback function.
 Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
 Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
 Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
 Message-id: 20200918080912.321299-3-coiby.xu@gmail.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  contrib/libvhost-user/libvhost-user.c | 1 +
 file changed, 1 insertion(+)
 diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c
 index XXXXXXX..XXXXXXX 100644
 --- a/contrib/libvhost-user/libvhost-user.c
 +++ b/contrib/libvhost-user/libvhost-user.c
 @@ -XXX,XX +XXX,XX @@ vu_deinit(VuDev *dev)
          }
          if (vq->kick_fd != -1) {
 +            dev->remove_watch(dev, vq->kick_fd);
              close(vq->kick_fd);
              vq->kick_fd = -1;
          }
 --
 .26.2

-[PULL v2 04/30] util/vhost-user-server: generic vhost user server
+[PULL v2 04/28] util/vhost-user-server: generic vhost user server
 ...
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
 Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
 Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
 Message-id: 20200918080912.321299-4-coiby.xu@gmail.com
+[Fixed size_t %lu -> %zu format string compiler error.
+--Stefan]
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  util/vhost-user-server.h |  65 ++++++
  util/vhost-user-server.c | 428 +++++++++++++++++++++++++++++++++++++++
  util/meson.build         |   1 +
 ...
 +        }
 +        read_bytes += rc;
 +        if (nfds_t > 0) {
 +            if (nfds + nfds_t > max_fds) {
 +                error_report("A maximum of %zu fds are allowed, "
-+                             "however got %lu fds now",
++                             "however got %zu fds now",
 +                             max_fds, nfds + nfds_t);
 +                goto fail;
 +            }
 +            memcpy(vmsg->fds + nfds, fds_t,
 +                   nfds_t *sizeof(vmsg->fds[0]));
 ...

-[PULL v2 05/30] block: move logical block size check function to a common utility function
+[PULL v2 05/28] block: move logical block size check function to a common utility function
 From: Coiby Xu <coiby.xu@gmail.com>
 Move the constants from hw/core/qdev-properties.c to
 util/block-helpers.h so that knowledge of the min/max values is
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
 Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
 Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
 Acked-by: Eduardo Habkost <ehabkost@redhat.com>
 Message-id: 20200918080912.321299-5-coiby.xu@gmail.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  util/block-helpers.h             | 19 +++++++++++++
  hw/core/qdev-properties-system.c | 31 ++++-----------------
  util/block-helpers.c             | 46 ++++++++++++++++++++++++++++++++
  util/meson.build                 |  1 +
 files changed, 71 insertions(+), 26 deletions(-)
  create mode 100644 util/block-helpers.h
  create mode 100644 util/block-helpers.c
 diff --git a/util/block-helpers.h b/util/block-helpers.h
 new file mode 100644
 index XXXXXXX..XXXXXXX
 --- /dev/null
 +++ b/util/block-helpers.h
 @@ -XXX,XX +XXX,XX @@
 +#ifndef BLOCK_HELPERS_H
 +#define BLOCK_HELPERS_H
 +
 +#include "qemu/units.h"
 +
 +/* lower limit is sector size */
 +#define MIN_BLOCK_SIZE          INT64_C(512)
 +#define MIN_BLOCK_SIZE_STR      "512 B"
 +/*
 + * upper limit is arbitrary, 2 MiB looks sufficient for all sensible uses, and
 + * matches qcow2 cluster size limit
 + */
 +#define MAX_BLOCK_SIZE          (2 * MiB)
 +#define MAX_BLOCK_SIZE_STR      "2 MiB"
 +
 +void check_block_size(const char *id, const char *name, int64_t value,
 +                      Error **errp);
 +
 +#endif /* BLOCK_HELPERS_H */
 diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c
 index XXXXXXX..XXXXXXX 100644
 --- a/hw/core/qdev-properties-system.c
 +++ b/hw/core/qdev-properties-system.c
 @@ -XXX,XX +XXX,XX @@
  #include "sysemu/blockdev.h"
  #include "net/net.h"
  #include "hw/pci/pci.h"
 +#include "util/block-helpers.h"
  static bool check_prop_still_unset(DeviceState *dev, const char *name,
                                     const void *old_val, const char *new_val,
 @@ -XXX,XX +XXX,XX @@ const PropertyInfo qdev_prop_losttickpolicy = {
  /* --- blocksize --- */
 -/* lower limit is sector size */
 -#define MIN_BLOCK_SIZE          512
 -#define MIN_BLOCK_SIZE_STR      "512 B"
 -/*
 - * upper limit is arbitrary, 2 MiB looks sufficient for all sensible uses, and
 - * matches qcow2 cluster size limit
 - */
 -#define MAX_BLOCK_SIZE          (2 * MiB)
 -#define MAX_BLOCK_SIZE_STR      "2 MiB"
 -
  static void set_blocksize(Object *obj, Visitor *v, const char *name,
                            void *opaque, Error **errp)
  {
 @@ -XXX,XX +XXX,XX @@ static void set_blocksize(Object *obj, Visitor *v, const char *name,
      Property *prop = opaque;
      uint32_t *ptr = qdev_get_prop_ptr(dev, prop);
      uint64_t value;
 +    Error *local_err = NULL;
      if (dev->realized) {
          qdev_prop_set_after_realize(dev, name, errp);
 @@ -XXX,XX +XXX,XX @@ static void set_blocksize(Object *obj, Visitor *v, const char *name,
      if (!visit_type_size(v, name, &value, errp)) {
          return;
      }
 -    /* value of 0 means "unset" */
 -    if (value && (value < MIN_BLOCK_SIZE || value > MAX_BLOCK_SIZE)) {
 -        error_setg(errp,
 -                   "Property %s.%s doesn't take value %" PRIu64
 -                   " (minimum: " MIN_BLOCK_SIZE_STR
 -                   ", maximum: " MAX_BLOCK_SIZE_STR ")",
 -                   dev->id ? : "", name, value);
 +    check_block_size(dev->id ? : "", name, value, &local_err);
 +    if (local_err) {
 +        error_propagate(errp, local_err);
          return;
      }
 -
 -    /* We rely on power-of-2 blocksizes for bitmasks */
 -    if ((value & (value - 1)) != 0) {
 -        error_setg(errp,
 -                  "Property %s.%s doesn't take value '%" PRId64 "', "
 -                  "it's not a power of 2", dev->id ?: "", name, (int64_t)value);
 -        return;
 -    }
 -
      *ptr = value;
  }
 diff --git a/util/block-helpers.c b/util/block-helpers.c
 new file mode 100644
 index XXXXXXX..XXXXXXX
 --- /dev/null
 +++ b/util/block-helpers.c
 @@ -XXX,XX +XXX,XX @@
 +/*
 + * Block utility functions
 + *
 + * Copyright IBM, Corp. 2011
 + * Copyright (c) 2020 Coiby Xu <coiby.xu@gmail.com>
 + *
 + * This work is licensed under the terms of the GNU GPL, version 2 or later.
 + * See the COPYING file in the top-level directory.
 + */
 +
 +#include "qemu/osdep.h"
 +#include "qapi/error.h"
 +#include "qapi/qmp/qerror.h"
 +#include "block-helpers.h"
 +
 +/**
 + * check_block_size:
 + * @id: The unique ID of the object
 + * @name: The name of the property being validated
 + * @value: The block size in bytes
 + * @errp: A pointer to an area to store an error
 + *
 + * This function checks that the block size meets the following conditions:
 + * 1. At least MIN_BLOCK_SIZE
 + * 2. No larger than MAX_BLOCK_SIZE
 + * 3. A power of 2
 + */
 +void check_block_size(const char *id, const char *name, int64_t value,
 +                      Error **errp)
 +{
 +    /* value of 0 means "unset" */
 +    if (value && (value < MIN_BLOCK_SIZE || value > MAX_BLOCK_SIZE)) {
 +        error_setg(errp, QERR_PROPERTY_VALUE_OUT_OF_RANGE,
 +                   id, name, value, MIN_BLOCK_SIZE, MAX_BLOCK_SIZE);
 +        return;
 +    }
 +
 +    /* We rely on power-of-2 blocksizes for bitmasks */
 +    if ((value & (value - 1)) != 0) {
 +        error_setg(errp,
 +                   "Property %s.%s doesn't take value '%" PRId64
 +                   "', it's not a power of 2",
 +                   id, name, value);
 +        return;
 +    }
 +}
 diff --git a/util/meson.build b/util/meson.build
 index XXXXXXX..XXXXXXX 100644
 --- a/util/meson.build
 +++ b/util/meson.build
 @@ -XXX,XX +XXX,XX @@ if have_block
    util_ss.add(files('nvdimm-utils.c'))
    util_ss.add(files('qemu-coroutine.c', 'qemu-coroutine-lock.c', 'qemu-coroutine-io.c'))
    util_ss.add(when: 'CONFIG_LINUX', if_true: files('vhost-user-server.c'))
 +  util_ss.add(files('block-helpers.c'))
    util_ss.add(files('qemu-coroutine-sleep.c'))
    util_ss.add(files('qemu-co-shared-resource.c'))
    util_ss.add(files('thread-pool.c', 'qemu-timer.c'))
 --
 .26.2

-[PULL v2 06/30] block/export: vhost-user block device backend server
+[PULL v2 06/28] block/export: vhost-user block device backend server
 ...
 Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
 Message-id: 20200918080912.321299-6-coiby.xu@gmail.com
 [Shorten "vhost_user_blk_server" string to "vhost_user_blk" to avoid the
 following compiler warning:
 ../block/export/vhost-user-blk-server.c:178:50: error: ‘%s’ directive output truncated writing 21 bytes into a region of size 20 [-Werror=format-truncation=]
+and fix "Invalid size %ld ..." ssize_t format string arguments for
+-bit hosts.
 --Stefan]
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  block/export/vhost-user-blk-server.h |  36 ++
  block/export/vhost-user-blk-server.c | 661 +++++++++++++++++++++++++++
 ...
 +                              uint32_t iovcnt, uint32_t type)
 +{
 +    struct virtio_blk_discard_write_zeroes desc;
 +    ssize_t size = iov_to_buf(iov, iovcnt, 0, &desc, sizeof(desc));
 +    if (unlikely(size != sizeof(desc))) {
-+        error_report("Invalid size %ld, expect %ld", size, sizeof(desc));
++        error_report("Invalid size %zd, expect %zu", size, sizeof(desc));
 +        return -EINVAL;
 +    }
 +
 +    VuBlockDev *vdev_blk = get_vu_block_device_by_server(req->server);
 +    uint64_t range[2] = { le64_to_cpu(desc.sector) << 9,
 ...

-[PULL v2 07/30] test: new qTest case to test the vhost-user-blk-server
+Deleted patch
-From: Coiby Xu <coiby.xu@gmail.com>
-This test case has the same tests as tests/virtio-blk-test.c except for
-tests have block_resize. Since vhost-user server can only server one
-client one time, two instances of vhost-user-blk-server are started by
-qemu-storage-daemon for the hotplug test.
-In order to not block scripts/tap-driver.pl, vhost-user-blk-server will
-send "quit" command to qemu-storage-daemon's QMP monitor. So a function
-is added to libqtest.c to establish socket connection with socket
-server.
-Suggested-by: Thomas Huth <thuth@redhat.com>
-Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
-Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
-Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
-Message-id: 20200918080912.321299-7-coiby.xu@gmail.com
-[Update meson.build to only test when CONFIG_TOOLS has built
-qemu-storage-daemon. This prevents CI failures with --disable-tools.
---Stefan]
-Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
----
- tests/qtest/libqos/libqtest.h       |  17 +
- tests/qtest/libqos/vhost-user-blk.h |  48 ++
- tests/qtest/libqos/vhost-user-blk.c | 129 +++++
- tests/qtest/libqtest.c              |  36 +-
- tests/qtest/vhost-user-blk-test.c   | 751 ++++++++++++++++++++++++++++
- tests/qtest/libqos/meson.build      |   1 +
- tests/qtest/meson.build             |   4 +-
-files changed, 983 insertions(+), 3 deletions(-)
- create mode 100644 tests/qtest/libqos/vhost-user-blk.h
- create mode 100644 tests/qtest/libqos/vhost-user-blk.c
- create mode 100644 tests/qtest/vhost-user-blk-test.c
-diff --git a/tests/qtest/libqos/libqtest.h b/tests/qtest/libqos/libqtest.h
-index XXXXXXX..XXXXXXX 100644
---- a/tests/qtest/libqos/libqtest.h
-+++ b/tests/qtest/libqos/libqtest.h
-@@ -XXX,XX +XXX,XX @@ void qtest_qmp_send(QTestState *s, const char *fmt, ...)
- void qtest_qmp_send_raw(QTestState *s, const char *fmt, ...)
-     GCC_FMT_ATTR(2, 3);
-+/**
-+ * qtest_socket_client:
-+ * @server_socket_path: the socket server's path
-+ *
-+ * Connect to a socket server.
-+ */
-+int qtest_socket_client(char *server_socket_path);
-+
-+/**
-+ * qtest_create_state_with_qmp_fd:
-+ * @fd: socket fd
-+ *
-+ * Wrap socket fd in QTestState to make use of qtest_qmp*
-+ * functions
-+ */
-+QTestState *qtest_create_state_with_qmp_fd(int fd);
-+
- /**
-  * qtest_vqmp_fds:
-  * @s: #QTestState instance to operate on.
-diff --git a/tests/qtest/libqos/vhost-user-blk.h b/tests/qtest/libqos/vhost-user-blk.h
-new file mode 100644
-index XXXXXXX..XXXXXXX
---- /dev/null
-+++ b/tests/qtest/libqos/vhost-user-blk.h
-@@ -XXX,XX +XXX,XX @@
-+/*
-+ * libqos driver framework
-+ *
-+ * Based on tests/qtest/libqos/virtio-blk.c
-+ *
-+ * Copyright (c) 2020 Coiby Xu <coiby.xu@gmail.com>
-+ *
-+ * Copyright (c) 2018 Emanuele Giuseppe Esposito <e.emanuelegiuseppe@gmail.com>
-+ *
-+ * This library is free software; you can redistribute it and/or
-+ * modify it under the terms of the GNU Lesser General Public
-+ * License version 2 as published by the Free Software Foundation.
-+ *
-+ * This library is distributed in the hope that it will be useful,
-+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
-+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-+ * Lesser General Public License for more details.
-+ *
-+ * You should have received a copy of the GNU Lesser General Public
-+ * License along with this library; if not, see <http://www.gnu.org/licenses/>
-+ */
-+
-+#ifndef TESTS_LIBQOS_VHOST_USER_BLK_H
-+#define TESTS_LIBQOS_VHOST_USER_BLK_H
-+
-+#include "qgraph.h"
-+#include "virtio.h"
-+#include "virtio-pci.h"
-+
-+typedef struct QVhostUserBlk QVhostUserBlk;
-+typedef struct QVhostUserBlkPCI QVhostUserBlkPCI;
-+typedef struct QVhostUserBlkDevice QVhostUserBlkDevice;
-+
-+struct QVhostUserBlk {
-+    QVirtioDevice *vdev;
-+};
-+
-+struct QVhostUserBlkPCI {
-+    QVirtioPCIDevice pci_vdev;
-+    QVhostUserBlk blk;
-+};
-+
-+struct QVhostUserBlkDevice {
-+    QOSGraphObject obj;
-+    QVhostUserBlk blk;
-+};
-+
-+#endif
-diff --git a/tests/qtest/libqos/vhost-user-blk.c b/tests/qtest/libqos/vhost-user-blk.c
-new file mode 100644
-index XXXXXXX..XXXXXXX
---- /dev/null
-+++ b/tests/qtest/libqos/vhost-user-blk.c
-@@ -XXX,XX +XXX,XX @@
-+/*
-+ * libqos driver framework
-+ *
-+ * Based on tests/qtest/libqos/virtio-blk.c
-+ *
-+ * Copyright (c) 2020 Coiby Xu <coiby.xu@gmail.com>
-+ *
-+ * Copyright (c) 2018 Emanuele Giuseppe Esposito <e.emanuelegiuseppe@gmail.com>
-+ *
-+ * This library is free software; you can redistribute it and/or
-+ * modify it under the terms of the GNU Lesser General Public
-+ * License version 2.1 as published by the Free Software Foundation.
-+ *
-+ * This library is distributed in the hope that it will be useful,
-+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
-+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-+ * Lesser General Public License for more details.
-+ *
-+ * You should have received a copy of the GNU Lesser General Public
-+ * License along with this library; if not, see <http://www.gnu.org/licenses/>
-+ */
-+
-+#include "qemu/osdep.h"
-+#include "libqtest.h"
-+#include "qemu/module.h"
-+#include "standard-headers/linux/virtio_blk.h"
-+#include "vhost-user-blk.h"
-+
-+#define PCI_SLOT                0x04
-+#define PCI_FN                  0x00
-+
-+/* virtio-blk-device */
-+static void *qvhost_user_blk_get_driver(QVhostUserBlk *v_blk,
-+                                    const char *interface)
-+{
-+    if (!g_strcmp0(interface, "vhost-user-blk")) {
-+        return v_blk;
-+    }
-+    if (!g_strcmp0(interface, "virtio")) {
-+        return v_blk->vdev;
-+    }
-+
-+    fprintf(stderr, "%s not present in vhost-user-blk-device\n", interface);
-+    g_assert_not_reached();
-+}
-+
-+static void *qvhost_user_blk_device_get_driver(void *object,
-+                                           const char *interface)
-+{
-+    QVhostUserBlkDevice *v_blk = object;
-+    return qvhost_user_blk_get_driver(&v_blk->blk, interface);
-+}
-+
-+static void *vhost_user_blk_device_create(void *virtio_dev,
-+                                      QGuestAllocator *t_alloc,
-+                                      void *addr)
-+{
-+    QVhostUserBlkDevice *vhost_user_blk = g_new0(QVhostUserBlkDevice, 1);
-+    QVhostUserBlk *interface = &vhost_user_blk->blk;
-+
-+    interface->vdev = virtio_dev;
-+
-+    vhost_user_blk->obj.get_driver = qvhost_user_blk_device_get_driver;
-+
-+    return &vhost_user_blk->obj;
-+}
-+
-+/* virtio-blk-pci */
-+static void *qvhost_user_blk_pci_get_driver(void *object, const char *interface)
-+{
-+    QVhostUserBlkPCI *v_blk = object;
-+    if (!g_strcmp0(interface, "pci-device")) {
-+        return v_blk->pci_vdev.pdev;
-+    }
-+    return qvhost_user_blk_get_driver(&v_blk->blk, interface);
-+}
-+
-+static void *vhost_user_blk_pci_create(void *pci_bus, QGuestAllocator *t_alloc,
-+                                      void *addr)
-+{
-+    QVhostUserBlkPCI *vhost_user_blk = g_new0(QVhostUserBlkPCI, 1);
-+    QVhostUserBlk *interface = &vhost_user_blk->blk;
-+    QOSGraphObject *obj = &vhost_user_blk->pci_vdev.obj;
-+
-+    virtio_pci_init(&vhost_user_blk->pci_vdev, pci_bus, addr);
-+    interface->vdev = &vhost_user_blk->pci_vdev.vdev;
-+
-+    g_assert_cmphex(interface->vdev->device_type, ==, VIRTIO_ID_BLOCK);
-+
-+    obj->get_driver = qvhost_user_blk_pci_get_driver;
-+
-+    return obj;
-+}
-+
-+static void vhost_user_blk_register_nodes(void)
-+{
-+    /*
-+     * FIXME: every test using these two nodes needs to setup a
-+     * -drive,id=drive0 otherwise QEMU is not going to start.
-+     * Therefore, we do not include "produces" edge for virtio
-+     * and pci-device yet.
-+     */
-+
-+    char *arg = g_strdup_printf("id=drv0,chardev=char1,addr=%x.%x",
-+                                PCI_SLOT, PCI_FN);
-+
-+    QPCIAddress addr = {
-+        .devfn = QPCI_DEVFN(PCI_SLOT, PCI_FN),
-+    };
-+
-+    QOSGraphEdgeOptions opts = { };
-+
-+    /* virtio-blk-device */
-+    /** opts.extra_device_opts = "drive=drive0"; */
-+    qos_node_create_driver("vhost-user-blk-device", vhost_user_blk_device_create);
-+    qos_node_consumes("vhost-user-blk-device", "virtio-bus", &opts);
-+    qos_node_produces("vhost-user-blk-device", "vhost-user-blk");
-+
-+    /* virtio-blk-pci */
-+    opts.extra_device_opts = arg;
-+    add_qpci_address(&opts, &addr);
-+    qos_node_create_driver("vhost-user-blk-pci", vhost_user_blk_pci_create);
-+    qos_node_consumes("vhost-user-blk-pci", "pci-bus", &opts);
-+    qos_node_produces("vhost-user-blk-pci", "vhost-user-blk");
-+
-+    g_free(arg);
-+}
-+
-+libqos_init(vhost_user_blk_register_nodes);
-diff --git a/tests/qtest/libqtest.c b/tests/qtest/libqtest.c
-index XXXXXXX..XXXXXXX 100644
---- a/tests/qtest/libqtest.c
-+++ b/tests/qtest/libqtest.c
-@@ -XXX,XX +XXX,XX @@
-  * Copyright IBM, Corp. 2012
-  * Copyright Red Hat, Inc. 2012
-  * Copyright SUSE LINUX Products GmbH 2013
-+ * Copyright Copyright (c) Coiby Xu
-  *
-  * Authors:
-  *  Anthony Liguori   <aliguori@us.ibm.com>
-  *  Paolo Bonzini     <pbonzini@redhat.com>
-  *  Andreas Färber    <afaerber@suse.de>
-+ *  Coiby Xu          <coiby.xu@gmail.com>
-  *
-  * This work is licensed under the terms of the GNU GPL, version 2 or later.
-  * See the COPYING file in the top-level directory.
-@@ -XXX,XX +XXX,XX @@ typedef struct QTestClientTransportOps {
-     QTestRecvFn     recv_line; /* for receiving qtest command responses */
- } QTestTransportOps;
--struct QTestState
--{
-+struct QTestState {
-     int fd;
-     int qmp_fd;
-     pid_t qemu_pid;  /* our child QEMU process */
-@@ -XXX,XX +XXX,XX @@ QDict *qtest_qmp_receive(QTestState *s)
-     return qmp_fd_receive(s->qmp_fd);
- }
-+QTestState *qtest_create_state_with_qmp_fd(int fd)
-+{
-+    QTestState *qmp_test_state = g_new0(QTestState, 1);
-+    qmp_test_state->qmp_fd = fd;
-+    return qmp_test_state;
-+}
-+
-+int qtest_socket_client(char *server_socket_path)
-+{
-+    struct sockaddr_un serv_addr;
-+    int sock;
-+    int ret;
-+    int retries = 0;
-+    sock = socket(PF_UNIX, SOCK_STREAM, 0);
-+    g_assert_cmpint(sock, !=, -1);
-+    serv_addr.sun_family = AF_UNIX;
-+    snprintf(serv_addr.sun_path, sizeof(serv_addr.sun_path), "%s",
-+             server_socket_path);
-+
-+    for (retries = 0; retries < 3; retries++) {
-+        ret = connect(sock, (struct sockaddr *)&serv_addr, sizeof(serv_addr));
-+        if (ret == 0) {
-+            break;
-+        }
-+        g_usleep(G_USEC_PER_SEC);
-+    }
-+
-+    g_assert_cmpint(ret, ==, 0);
-+    return sock;
-+}
-+
- /**
-  * Allow users to send a message without waiting for the reply,
-  * in the case that they choose to discard all replies up until
-diff --git a/tests/qtest/vhost-user-blk-test.c b/tests/qtest/vhost-user-blk-test.c
-new file mode 100644
-index XXXXXXX..XXXXXXX
---- /dev/null
-+++ b/tests/qtest/vhost-user-blk-test.c
-@@ -XXX,XX +XXX,XX @@
-+/*
-+ * QTest testcase for Vhost-user Block Device
-+ *
-+ * Based on tests/qtest//virtio-blk-test.c
-+
-+ * Copyright (c) 2014 SUSE LINUX Products GmbH
-+ * Copyright (c) 2014 Marc Marí
-+ * Copyright (c) 2020 Coiby Xu
-+ *
-+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
-+ * See the COPYING file in the top-level directory.
-+ */
-+
-+#include "qemu/osdep.h"
-+#include "libqtest-single.h"
-+#include "qemu/bswap.h"
-+#include "qemu/module.h"
-+#include "standard-headers/linux/virtio_blk.h"
-+#include "standard-headers/linux/virtio_pci.h"
-+#include "libqos/qgraph.h"
-+#include "libqos/vhost-user-blk.h"
-+#include "libqos/libqos-pc.h"
-+
-+#define TEST_IMAGE_SIZE         (64 * 1024 * 1024)
-+#define QVIRTIO_BLK_TIMEOUT_US  (30 * 1000 * 1000)
-+#define PCI_SLOT_HP             0x06
-+
-+typedef struct QVirtioBlkReq {
-+    uint32_t type;
-+    uint32_t ioprio;
-+    uint64_t sector;
-+    char *data;
-+    uint8_t status;
-+} QVirtioBlkReq;
-+
-+#ifdef HOST_WORDS_BIGENDIAN
-+static const bool host_is_big_endian = true;
-+#else
-+static const bool host_is_big_endian; /* false */
-+#endif
-+
-+static inline void virtio_blk_fix_request(QVirtioDevice *d, QVirtioBlkReq *req)
-+{
-+    if (qvirtio_is_big_endian(d) != host_is_big_endian) {
-+        req->type = bswap32(req->type);
-+        req->ioprio = bswap32(req->ioprio);
-+        req->sector = bswap64(req->sector);
-+    }
-+}
-+
-+static inline void virtio_blk_fix_dwz_hdr(QVirtioDevice *d,
-+    struct virtio_blk_discard_write_zeroes *dwz_hdr)
-+{
-+    if (qvirtio_is_big_endian(d) != host_is_big_endian) {
-+        dwz_hdr->sector = bswap64(dwz_hdr->sector);
-+        dwz_hdr->num_sectors = bswap32(dwz_hdr->num_sectors);
-+        dwz_hdr->flags = bswap32(dwz_hdr->flags);
-+    }
-+}
-+
-+static uint64_t virtio_blk_request(QGuestAllocator *alloc, QVirtioDevice *d,
-+                                   QVirtioBlkReq *req, uint64_t data_size)
-+{
-+    uint64_t addr;
-+    uint8_t status = 0xFF;
-+    QTestState *qts = global_qtest;
-+
-+    switch (req->type) {
-+    case VIRTIO_BLK_T_IN:
-+    case VIRTIO_BLK_T_OUT:
-+        g_assert_cmpuint(data_size % 512, ==, 0);
-+        break;
-+    case VIRTIO_BLK_T_DISCARD:
-+    case VIRTIO_BLK_T_WRITE_ZEROES:
-+        g_assert_cmpuint(data_size %
-+                         sizeof(struct virtio_blk_discard_write_zeroes), ==, 0);
-+        break;
-+    default:
-+        g_assert_cmpuint(data_size, ==, 0);
-+    }
-+
-+    addr = guest_alloc(alloc, sizeof(*req) + data_size);
-+
-+    virtio_blk_fix_request(d, req);
-+
-+    qtest_memwrite(qts, addr, req, 16);
-+    qtest_memwrite(qts, addr + 16, req->data, data_size);
-+    qtest_memwrite(qts, addr + 16 + data_size, &status, sizeof(status));
-+
-+    return addr;
-+}
-+
-+/* Returns the request virtqueue so the caller can perform further tests */
-+static QVirtQueue *test_basic(QVirtioDevice *dev, QGuestAllocator *alloc)
-+{
-+    QVirtioBlkReq req;
-+    uint64_t req_addr;
-+    uint64_t capacity;
-+    uint64_t features;
-+    uint32_t free_head;
-+    uint8_t status;
-+    char *data;
-+    QTestState *qts = global_qtest;
-+    QVirtQueue *vq;
-+
-+    features = qvirtio_get_features(dev);
-+    features = features & ~(QVIRTIO_F_BAD_FEATURE |
-+                    (1u << VIRTIO_RING_F_INDIRECT_DESC) |
-+                    (1u << VIRTIO_RING_F_EVENT_IDX) |
-+                    (1u << VIRTIO_BLK_F_SCSI));
-+    qvirtio_set_features(dev, features);
-+
-+    capacity = qvirtio_config_readq(dev, 0);
-+    g_assert_cmpint(capacity, ==, TEST_IMAGE_SIZE / 512);
-+
-+    vq = qvirtqueue_setup(dev, alloc, 0);
-+
-+    qvirtio_set_driver_ok(dev);
-+
-+    /* Write and read with 3 descriptor layout */
-+    /* Write request */
-+    req.type = VIRTIO_BLK_T_OUT;
-+    req.ioprio = 1;
-+    req.sector = 0;
-+    req.data = g_malloc0(512);
-+    strcpy(req.data, "TEST");
-+
-+    req_addr = virtio_blk_request(alloc, dev, &req, 512);
-+
-+    g_free(req.data);
-+
-+    free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
-+    qvirtqueue_add(qts, vq, req_addr + 16, 512, false, true);
-+    qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
-+
-+    qvirtqueue_kick(qts, dev, vq, free_head);
-+
-+    qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
-+                           QVIRTIO_BLK_TIMEOUT_US);
-+    status = readb(req_addr + 528);
-+    g_assert_cmpint(status, ==, 0);
-+
-+    guest_free(alloc, req_addr);
-+
-+    /* Read request */
-+    req.type = VIRTIO_BLK_T_IN;
-+    req.ioprio = 1;
-+    req.sector = 0;
-+    req.data = g_malloc0(512);
-+
-+    req_addr = virtio_blk_request(alloc, dev, &req, 512);
-+
-+    g_free(req.data);
-+
-+    free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
-+    qvirtqueue_add(qts, vq, req_addr + 16, 512, true, true);
-+    qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
-+
-+    qvirtqueue_kick(qts, dev, vq, free_head);
-+
-+    qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
-+                           QVIRTIO_BLK_TIMEOUT_US);
-+    status = readb(req_addr + 528);
-+    g_assert_cmpint(status, ==, 0);
-+
-+    data = g_malloc0(512);
-+    qtest_memread(qts, req_addr + 16, data, 512);
-+    g_assert_cmpstr(data, ==, "TEST");
-+    g_free(data);
-+
-+    guest_free(alloc, req_addr);
-+
-+    if (features & (1u << VIRTIO_BLK_F_WRITE_ZEROES)) {
-+        struct virtio_blk_discard_write_zeroes dwz_hdr;
-+        void *expected;
-+
-+        /*
-+         * WRITE_ZEROES request on the same sector of previous test where
-+         * we wrote "TEST".
-+         */
-+        req.type = VIRTIO_BLK_T_WRITE_ZEROES;
-+        req.data = (char *) &dwz_hdr;
-+        dwz_hdr.sector = 0;
-+        dwz_hdr.num_sectors = 1;
-+        dwz_hdr.flags = 0;
-+
-+        virtio_blk_fix_dwz_hdr(dev, &dwz_hdr);
-+
-+        req_addr = virtio_blk_request(alloc, dev, &req, sizeof(dwz_hdr));
-+
-+        free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
-+        qvirtqueue_add(qts, vq, req_addr + 16, sizeof(dwz_hdr), false, true);
-+        qvirtqueue_add(qts, vq, req_addr + 16 + sizeof(dwz_hdr), 1, true,
-+                       false);
-+
-+        qvirtqueue_kick(qts, dev, vq, free_head);
-+
-+        qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
-+                               QVIRTIO_BLK_TIMEOUT_US);
-+        status = readb(req_addr + 16 + sizeof(dwz_hdr));
-+        g_assert_cmpint(status, ==, 0);
-+
-+        guest_free(alloc, req_addr);
-+
-+        /* Read request to check if the sector contains all zeroes */
-+        req.type = VIRTIO_BLK_T_IN;
-+        req.ioprio = 1;
-+        req.sector = 0;
-+        req.data = g_malloc0(512);
-+
-+        req_addr = virtio_blk_request(alloc, dev, &req, 512);
-+
-+        g_free(req.data);
-+
-+        free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
-+        qvirtqueue_add(qts, vq, req_addr + 16, 512, true, true);
-+        qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
-+
-+        qvirtqueue_kick(qts, dev, vq, free_head);
-+
-+        qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
-+                               QVIRTIO_BLK_TIMEOUT_US);
-+        status = readb(req_addr + 528);
-+        g_assert_cmpint(status, ==, 0);
-+
-+        data = g_malloc(512);
-+        expected = g_malloc0(512);
-+        qtest_memread(qts, req_addr + 16, data, 512);
-+        g_assert_cmpmem(data, 512, expected, 512);
-+        g_free(expected);
-+        g_free(data);
-+
-+        guest_free(alloc, req_addr);
-+    }
-+
-+    if (features & (1u << VIRTIO_BLK_F_DISCARD)) {
-+        struct virtio_blk_discard_write_zeroes dwz_hdr;
-+
-+        req.type = VIRTIO_BLK_T_DISCARD;
-+        req.data = (char *) &dwz_hdr;
-+        dwz_hdr.sector = 0;
-+        dwz_hdr.num_sectors = 1;
-+        dwz_hdr.flags = 0;
-+
-+        virtio_blk_fix_dwz_hdr(dev, &dwz_hdr);
-+
-+        req_addr = virtio_blk_request(alloc, dev, &req, sizeof(dwz_hdr));
-+
-+        free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
-+        qvirtqueue_add(qts, vq, req_addr + 16, sizeof(dwz_hdr), false, true);
-+        qvirtqueue_add(qts, vq, req_addr + 16 + sizeof(dwz_hdr),
-+                       1, true, false);
-+
-+        qvirtqueue_kick(qts, dev, vq, free_head);
-+
-+        qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
-+                               QVIRTIO_BLK_TIMEOUT_US);
-+        status = readb(req_addr + 16 + sizeof(dwz_hdr));
-+        g_assert_cmpint(status, ==, 0);
-+
-+        guest_free(alloc, req_addr);
-+    }
-+
-+    if (features & (1u << VIRTIO_F_ANY_LAYOUT)) {
-+        /* Write and read with 2 descriptor layout */
-+        /* Write request */
-+        req.type = VIRTIO_BLK_T_OUT;
-+        req.ioprio = 1;
-+        req.sector = 1;
-+        req.data = g_malloc0(512);
-+        strcpy(req.data, "TEST");
-+
-+        req_addr = virtio_blk_request(alloc, dev, &req, 512);
-+
-+        g_free(req.data);
-+
-+        free_head = qvirtqueue_add(qts, vq, req_addr, 528, false, true);
-+        qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
-+        qvirtqueue_kick(qts, dev, vq, free_head);
-+
-+        qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
-+                               QVIRTIO_BLK_TIMEOUT_US);
-+        status = readb(req_addr + 528);
-+        g_assert_cmpint(status, ==, 0);
-+
-+        guest_free(alloc, req_addr);
-+
-+        /* Read request */
-+        req.type = VIRTIO_BLK_T_IN;
-+        req.ioprio = 1;
-+        req.sector = 1;
-+        req.data = g_malloc0(512);
-+
-+        req_addr = virtio_blk_request(alloc, dev, &req, 512);
-+
-+        g_free(req.data);
-+
-+        free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
-+        qvirtqueue_add(qts, vq, req_addr + 16, 513, true, false);
-+
-+        qvirtqueue_kick(qts, dev, vq, free_head);
-+
-+        qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
-+                               QVIRTIO_BLK_TIMEOUT_US);
-+        status = readb(req_addr + 528);
-+        g_assert_cmpint(status, ==, 0);
-+
-+        data = g_malloc0(512);
-+        qtest_memread(qts, req_addr + 16, data, 512);
-+        g_assert_cmpstr(data, ==, "TEST");
-+        g_free(data);
-+
-+        guest_free(alloc, req_addr);
-+    }
-+
-+    return vq;
-+}
-+
-+static void basic(void *obj, void *data, QGuestAllocator *t_alloc)
-+{
-+    QVhostUserBlk *blk_if = obj;
-+    QVirtQueue *vq;
-+
-+    vq = test_basic(blk_if->vdev, t_alloc);
-+    qvirtqueue_cleanup(blk_if->vdev->bus, vq, t_alloc);
-+
-+}
-+
-+static void indirect(void *obj, void *u_data, QGuestAllocator *t_alloc)
-+{
-+    QVirtQueue *vq;
-+    QVhostUserBlk *blk_if = obj;
-+    QVirtioDevice *dev = blk_if->vdev;
-+    QVirtioBlkReq req;
-+    QVRingIndirectDesc *indirect;
-+    uint64_t req_addr;
-+    uint64_t capacity;
-+    uint64_t features;
-+    uint32_t free_head;
-+    uint8_t status;
-+    char *data;
-+    QTestState *qts = global_qtest;
-+
-+    features = qvirtio_get_features(dev);
-+    g_assert_cmphex(features & (1u << VIRTIO_RING_F_INDIRECT_DESC), !=, 0);
-+    features = features & ~(QVIRTIO_F_BAD_FEATURE |
-+                            (1u << VIRTIO_RING_F_EVENT_IDX) |
-+                            (1u << VIRTIO_BLK_F_SCSI));
-+    qvirtio_set_features(dev, features);
-+
-+    capacity = qvirtio_config_readq(dev, 0);
-+    g_assert_cmpint(capacity, ==, TEST_IMAGE_SIZE / 512);
-+
-+    vq = qvirtqueue_setup(dev, t_alloc, 0);
-+    qvirtio_set_driver_ok(dev);
-+
-+    /* Write request */
-+    req.type = VIRTIO_BLK_T_OUT;
-+    req.ioprio = 1;
-+    req.sector = 0;
-+    req.data = g_malloc0(512);
-+    strcpy(req.data, "TEST");
-+
-+    req_addr = virtio_blk_request(t_alloc, dev, &req, 512);
-+
-+    g_free(req.data);
-+
-+    indirect = qvring_indirect_desc_setup(qts, dev, t_alloc, 2);
-+    qvring_indirect_desc_add(dev, qts, indirect, req_addr, 528, false);
-+    qvring_indirect_desc_add(dev, qts, indirect, req_addr + 528, 1, true);
-+    free_head = qvirtqueue_add_indirect(qts, vq, indirect);
-+    qvirtqueue_kick(qts, dev, vq, free_head);
-+
-+    qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
-+                           QVIRTIO_BLK_TIMEOUT_US);
-+    status = readb(req_addr + 528);
-+    g_assert_cmpint(status, ==, 0);
-+
-+    g_free(indirect);
-+    guest_free(t_alloc, req_addr);
-+
-+    /* Read request */
-+    req.type = VIRTIO_BLK_T_IN;
-+    req.ioprio = 1;
-+    req.sector = 0;
-+    req.data = g_malloc0(512);
-+    strcpy(req.data, "TEST");
-+
-+    req_addr = virtio_blk_request(t_alloc, dev, &req, 512);
-+
-+    g_free(req.data);
-+
-+    indirect = qvring_indirect_desc_setup(qts, dev, t_alloc, 2);
-+    qvring_indirect_desc_add(dev, qts, indirect, req_addr, 16, false);
-+    qvring_indirect_desc_add(dev, qts, indirect, req_addr + 16, 513, true);
-+    free_head = qvirtqueue_add_indirect(qts, vq, indirect);
-+    qvirtqueue_kick(qts, dev, vq, free_head);
-+
-+    qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
-+                           QVIRTIO_BLK_TIMEOUT_US);
-+    status = readb(req_addr + 528);
-+    g_assert_cmpint(status, ==, 0);
-+
-+    data = g_malloc0(512);
-+    qtest_memread(qts, req_addr + 16, data, 512);
-+    g_assert_cmpstr(data, ==, "TEST");
-+    g_free(data);
-+
-+    g_free(indirect);
-+    guest_free(t_alloc, req_addr);
-+    qvirtqueue_cleanup(dev->bus, vq, t_alloc);
-+}
-+
-+static void idx(void *obj, void *u_data, QGuestAllocator *t_alloc)
-+{
-+    QVirtQueue *vq;
-+    QVhostUserBlkPCI *blk = obj;
-+    QVirtioPCIDevice *pdev = &blk->pci_vdev;
-+    QVirtioDevice *dev = &pdev->vdev;
-+    QVirtioBlkReq req;
-+    uint64_t req_addr;
-+    uint64_t capacity;
-+    uint64_t features;
-+    uint32_t free_head;
-+    uint32_t write_head;
-+    uint32_t desc_idx;
-+    uint8_t status;
-+    char *data;
-+    QOSGraphObject *blk_object = obj;
-+    QPCIDevice *pci_dev = blk_object->get_driver(blk_object, "pci-device");
-+    QTestState *qts = global_qtest;
-+
-+    if (qpci_check_buggy_msi(pci_dev)) {
-+        return;
-+    }
-+
-+    qpci_msix_enable(pdev->pdev);
-+    qvirtio_pci_set_msix_configuration_vector(pdev, t_alloc, 0);
-+
-+    features = qvirtio_get_features(dev);
-+    features = features & ~(QVIRTIO_F_BAD_FEATURE |
-+                            (1u << VIRTIO_RING_F_INDIRECT_DESC) |
-+                            (1u << VIRTIO_F_NOTIFY_ON_EMPTY) |
-+                            (1u << VIRTIO_BLK_F_SCSI));
-+    qvirtio_set_features(dev, features);
-+
-+    capacity = qvirtio_config_readq(dev, 0);
-+    g_assert_cmpint(capacity, ==, TEST_IMAGE_SIZE / 512);
-+
-+    vq = qvirtqueue_setup(dev, t_alloc, 0);
-+    qvirtqueue_pci_msix_setup(pdev, (QVirtQueuePCI *)vq, t_alloc, 1);
-+
-+    qvirtio_set_driver_ok(dev);
-+
-+    /* Write request */
-+    req.type = VIRTIO_BLK_T_OUT;
-+    req.ioprio = 1;
-+    req.sector = 0;
-+    req.data = g_malloc0(512);
-+    strcpy(req.data, "TEST");
-+
-+    req_addr = virtio_blk_request(t_alloc, dev, &req, 512);
-+
-+    g_free(req.data);
-+
-+    free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
-+    qvirtqueue_add(qts, vq, req_addr + 16, 512, false, true);
-+    qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
-+    qvirtqueue_kick(qts, dev, vq, free_head);
-+
-+    qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
-+                           QVIRTIO_BLK_TIMEOUT_US);
-+
-+    /* Write request */
-+    req.type = VIRTIO_BLK_T_OUT;
-+    req.ioprio = 1;
-+    req.sector = 1;
-+    req.data = g_malloc0(512);
-+    strcpy(req.data, "TEST");
-+
-+    req_addr = virtio_blk_request(t_alloc, dev, &req, 512);
-+
-+    g_free(req.data);
-+
-+    /* Notify after processing the third request */
-+    qvirtqueue_set_used_event(qts, vq, 2);
-+    free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
-+    qvirtqueue_add(qts, vq, req_addr + 16, 512, false, true);
-+    qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
-+    qvirtqueue_kick(qts, dev, vq, free_head);
-+    write_head = free_head;
-+
-+    /* No notification expected */
-+    status = qvirtio_wait_status_byte_no_isr(qts, dev,
-+                                             vq, req_addr + 528,
-+                                             QVIRTIO_BLK_TIMEOUT_US);
-+    g_assert_cmpint(status, ==, 0);
-+
-+    guest_free(t_alloc, req_addr);
-+
-+    /* Read request */
-+    req.type = VIRTIO_BLK_T_IN;
-+    req.ioprio = 1;
-+    req.sector = 1;
-+    req.data = g_malloc0(512);
-+
-+    req_addr = virtio_blk_request(t_alloc, dev, &req, 512);
-+
-+    g_free(req.data);
-+
-+    free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
-+    qvirtqueue_add(qts, vq, req_addr + 16, 512, true, true);
-+    qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
-+
-+    qvirtqueue_kick(qts, dev, vq, free_head);
-+
-+    /* We get just one notification for both requests */
-+    qvirtio_wait_used_elem(qts, dev, vq, write_head, NULL,
-+                           QVIRTIO_BLK_TIMEOUT_US);
-+    g_assert(qvirtqueue_get_buf(qts, vq, &desc_idx, NULL));
-+    g_assert_cmpint(desc_idx, ==, free_head);
-+
-+    status = readb(req_addr + 528);
-+    g_assert_cmpint(status, ==, 0);
-+
-+    data = g_malloc0(512);
-+    qtest_memread(qts, req_addr + 16, data, 512);
-+    g_assert_cmpstr(data, ==, "TEST");
-+    g_free(data);
-+
-+    guest_free(t_alloc, req_addr);
-+
-+    /* End test */
-+    qpci_msix_disable(pdev->pdev);
-+
-+    qvirtqueue_cleanup(dev->bus, vq, t_alloc);
-+}
-+
-+static void pci_hotplug(void *obj, void *data, QGuestAllocator *t_alloc)
-+{
-+    QVirtioPCIDevice *dev1 = obj;
-+    QVirtioPCIDevice *dev;
-+    QTestState *qts = dev1->pdev->bus->qts;
-+
-+    /* plug secondary disk */
-+    qtest_qmp_device_add(qts, "vhost-user-blk-pci", "drv1",
-+                         "{'addr': %s, 'chardev': 'char2'}",
-+                         stringify(PCI_SLOT_HP) ".0");
-+
-+    dev = virtio_pci_new(dev1->pdev->bus,
-+                         &(QPCIAddress) { .devfn = QPCI_DEVFN(PCI_SLOT_HP, 0)
-+                                        });
-+    g_assert_nonnull(dev);
-+    g_assert_cmpint(dev->vdev.device_type, ==, VIRTIO_ID_BLOCK);
-+    qvirtio_pci_device_disable(dev);
-+    qos_object_destroy((QOSGraphObject *)dev);
-+
-+    /* unplug secondary disk */
-+    qpci_unplug_acpi_device_test(qts, "drv1", PCI_SLOT_HP);
-+}
-+
-+/*
-+ * Check that setting the vring addr on a non-existent virtqueue does
-+ * not crash.
-+ */
-+static void test_nonexistent_virtqueue(void *obj, void *data,
-+                                       QGuestAllocator *t_alloc)
-+{
-+    QVhostUserBlkPCI *blk = obj;
-+    QVirtioPCIDevice *pdev = &blk->pci_vdev;
-+    QPCIBar bar0;
-+    QPCIDevice *dev;
-+
-+    dev = qpci_device_find(pdev->pdev->bus, QPCI_DEVFN(4, 0));
-+    g_assert(dev != NULL);
-+    qpci_device_enable(dev);
-+
-+    bar0 = qpci_iomap(dev, 0, NULL);
-+
-+    qpci_io_writeb(dev, bar0, VIRTIO_PCI_QUEUE_SEL, 2);
-+    qpci_io_writel(dev, bar0, VIRTIO_PCI_QUEUE_PFN, 1);
-+
-+    g_free(dev);
-+}
-+
-+static const char *qtest_qemu_storage_daemon_binary(void)
-+{
-+    const char *qemu_storage_daemon_bin;
-+
-+    qemu_storage_daemon_bin = getenv("QTEST_QEMU_STORAGE_DAEMON_BINARY");
-+    if (!qemu_storage_daemon_bin) {
-+        fprintf(stderr, "Environment variable "
-+                        "QTEST_QEMU_STORAGE_DAEMON_BINARY required\n");
-+        exit(0);
-+    }
-+
-+    return qemu_storage_daemon_bin;
-+}
-+
-+static void drive_destroy(void *path)
-+{
-+    unlink(path);
-+    g_free(path);
-+    qos_invalidate_command_line();
-+}
-+
-+static char *drive_create(void)
-+{
-+    int fd, ret;
-+    /** vhost-user-blk won't recognize drive located in /tmp */
-+    char *t_path = g_strdup("qtest.XXXXXX");
-+
-+    /** Create a temporary raw image */
-+    fd = mkstemp(t_path);
-+    g_assert_cmpint(fd, >=, 0);
-+    ret = ftruncate(fd, TEST_IMAGE_SIZE);
-+    g_assert_cmpint(ret, ==, 0);
-+    close(fd);
-+
-+    g_test_queue_destroy(drive_destroy, t_path);
-+    return t_path;
-+}
-+
-+static char sock_path_tempate[] = "/tmp/qtest.vhost_user_blk.XXXXXX";
-+static char qmp_sock_path_tempate[] = "/tmp/qtest.vhost_user_blk.qmp.XXXXXX";
-+
-+static void quit_storage_daemon(void *qmp_test_state)
-+{
-+    const char quit_str[] = "{ 'execute': 'quit' }";
-+
-+    /* Before quiting storate-daemon, quit qemu to avoid dubious messages */
-+    qobject_unref(qtest_qmp(global_qtest, quit_str));
-+
-+    /*
-+     * Give storage-daemon enough time to wake up&terminate
-+     * vu_client_trip coroutine so the Coroutine object could
-+     * be cleaned up. Otherwise LeakSanitizer would complain
-+     * about memory leaks.
-+     */
-+    g_usleep(1000);
-+
-+    qobject_unref(qtest_qmp((QTestState *)qmp_test_state, quit_str));
-+    g_free(qmp_test_state);
-+}
-+
-+static char *start_vhost_user_blk(GString *cmd_line, int vus_instances)
-+{
-+    const char *vhost_user_blk_bin = qtest_qemu_storage_daemon_binary();
-+    int fd, qmp_fd, i;
-+    QTestState *qmp_test_state;
-+    gchar *img_path;
-+    char *sock_path = NULL;
-+    char *qmp_sock_path = g_strdup(qmp_sock_path_tempate);
-+    GString *storage_daemon_command = g_string_new(NULL);
-+
-+    qmp_fd = mkstemp(qmp_sock_path);
-+    g_assert_cmpint(qmp_fd, >=, 0);
-+    g_test_queue_destroy(drive_destroy, qmp_sock_path);
-+
-+    g_string_append_printf(storage_daemon_command,
-+            "exec %s "
-+            "--chardev socket,id=qmp,path=%s,server,nowait --monitor chardev=qmp ",
-+            vhost_user_blk_bin, qmp_sock_path);
-+
-+    g_string_append_printf(cmd_line,
-+            " -object memory-backend-memfd,id=mem,size=128M,share=on -numa node,memdev=mem ");
-+
-+    for (i = 0; i < vus_instances; i++) {
-+        sock_path = g_strdup(sock_path_tempate);
-+        fd = mkstemp(sock_path);
-+        g_assert_cmpint(fd, >=, 0);
-+        g_test_queue_destroy(drive_destroy, sock_path);
-+        /* create image file */
-+        img_path = drive_create();
-+        g_string_append_printf(storage_daemon_command,
-+            "--blockdev driver=file,node-name=disk%d,filename=%s "
-+            "--object vhost-user-blk-server,id=disk%d,unix-socket=%s,"
-+            "node-name=disk%i,writable=on ",
-+            i, img_path, i, sock_path, i);
-+
-+        g_string_append_printf(cmd_line, "-chardev socket,id=char%d,path=%s ",
-+                               i + 1, sock_path);
-+    }
-+
-+    g_test_message("starting vhost-user backend: %s",
-+                   storage_daemon_command->str);
-+    pid_t pid = fork();
-+    if (pid == 0) {
-+        execlp("/bin/sh", "sh", "-c", storage_daemon_command->str, NULL);
-+        exit(1);
-+    }
-+    g_string_free(storage_daemon_command, true);
-+
-+    qmp_test_state = qtest_create_state_with_qmp_fd(
-+                             qtest_socket_client(qmp_sock_path));
-+    /*
-+     * Ask qemu-storage-daemon to quit so it
-+     * will not block scripts/tap-driver.pl.
-+     */
-+    g_test_queue_destroy(quit_storage_daemon, qmp_test_state);
-+
-+    qobject_unref(qtest_qmp(qmp_test_state, "{'execute': 'qmp_capabilities'}"));
-+    return sock_path;
-+}
-+
-+static void *vhost_user_blk_test_setup(GString *cmd_line, void *arg)
-+{
-+    start_vhost_user_blk(cmd_line, 1);
-+    return arg;
-+}
-+
-+/*
-+ * Setup for hotplug.
-+ *
-+ * Since vhost-user server only serves one vhost-user client one time,
-+ * another exprot
-+ *
-+ */
-+static void *vhost_user_blk_hotplug_test_setup(GString *cmd_line, void *arg)
-+{
-+    /* "-chardev socket,id=char2" is used for pci_hotplug*/
-+    start_vhost_user_blk(cmd_line, 2);
-+    return arg;
-+}
-+
-+static void register_vhost_user_blk_test(void)
-+{
-+    QOSGraphTestOptions opts = {
-+        .before = vhost_user_blk_test_setup,
-+    };
-+
-+    /*
-+     * tests for vhost-user-blk and vhost-user-blk-pci
-+     * The tests are borrowed from tests/virtio-blk-test.c. But some tests
-+     * regarding block_resize don't work for vhost-user-blk.
-+     * vhost-user-blk device doesn't have -drive, so tests containing
-+     * block_resize are also abandoned,
-+     *  - config
-+     *  - resize
-+     */
-+    qos_add_test("basic", "vhost-user-blk", basic, &opts);
-+    qos_add_test("indirect", "vhost-user-blk", indirect, &opts);
-+    qos_add_test("idx", "vhost-user-blk-pci", idx, &opts);
-+    qos_add_test("nxvirtq", "vhost-user-blk-pci",
-+                 test_nonexistent_virtqueue, &opts);
-+
-+    opts.before = vhost_user_blk_hotplug_test_setup;
-+    qos_add_test("hotplug", "vhost-user-blk-pci", pci_hotplug, &opts);
-+}
-+
-+libqos_init(register_vhost_user_blk_test);
-diff --git a/tests/qtest/libqos/meson.build b/tests/qtest/libqos/meson.build
-index XXXXXXX..XXXXXXX 100644
---- a/tests/qtest/libqos/meson.build
-+++ b/tests/qtest/libqos/meson.build
-@@ -XXX,XX +XXX,XX @@ libqos_srcs = files('../libqtest.c',
-         'virtio-9p.c',
-         'virtio-balloon.c',
-         'virtio-blk.c',
-+        'vhost-user-blk.c',
-         'virtio-mmio.c',
-         'virtio-net.c',
-         'virtio-pci.c',
-diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
-index XXXXXXX..XXXXXXX 100644
---- a/tests/qtest/meson.build
-+++ b/tests/qtest/meson.build
-@@ -XXX,XX +XXX,XX @@ qos_test_ss.add(
- )
- qos_test_ss.add(when: 'CONFIG_VIRTFS', if_true: files('virtio-9p-test.c'))
- qos_test_ss.add(when: 'CONFIG_VHOST_USER', if_true: files('vhost-user-test.c'))
-+qos_test_ss.add(when: ['CONFIG_LINUX', 'CONFIG_TOOLS'], if_true: files('vhost-user-blk-test.c'))
- extra_qtest_deps = {
-   'bios-tables-test': [io],
-@@ -XXX,XX +XXX,XX @@ foreach dir : target_dirs
-   endif
-   qtest_env.set('G_TEST_DBUS_DAEMON', meson.source_root() / 'tests/dbus-vmstate-daemon.sh')
-   qtest_env.set('QTEST_QEMU_BINARY', './qemu-system-' + target_base)
--
-+  qtest_env.set('QTEST_QEMU_STORAGE_DAEMON_BINARY', './storage-daemon/qemu-storage-daemon')
-+
-   foreach test : qtests
-     # Executables are shared across targets, declare them only the first time we
-     # encounter them
---
-.26.2

-[PULL v2 08/30] MAINTAINERS: Add vhost-user block device backend server maintainer
+[PULL v2 07/28] MAINTAINERS: Add vhost-user block device backend server maintainer
 ...
 Suggested-by: Stefano Garzarella <sgarzare@redhat.com>
 Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
 Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
 Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
 Message-id: 20200918080912.321299-8-coiby.xu@gmail.com
+[Removed reference to vhost-user-blk-test.c, it will be sent in a
+separate pull request.
+--Stefan]
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
- MAINTAINERS | 8 ++++++++
+ MAINTAINERS | 7 +++++++
-file changed, 8 insertions(+)
+file changed, 7 insertions(+)
 diff --git a/MAINTAINERS b/MAINTAINERS
 index XXXXXXX..XXXXXXX 100644
 --- a/MAINTAINERS
 +++ b/MAINTAINERS
 ...
 +Vhost-user block device backend server
 +M: Coiby Xu <Coiby.Xu@gmail.com>
 +S: Maintained
 +F: block/export/vhost-user-blk-server.c
 +F: util/vhost-user-server.c
-+F: tests/qtest/vhost-user-blk-test.c
 +F: tests/qtest/libqos/vhost-user-blk.c
 +
  Replication
  M: Wen Congyang <wencongyang2@huawei.com>
  M: Xie Changlong <xiechanglong.d@gmail.com>
 --
 .26.2

-[PULL v2 09/30] util/vhost-user-server: s/fileds/fields/ typo fix
+[PULL v2 08/28] util/vhost-user-server: s/fileds/fields/ typo fix
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Message-id: 20200924151549.913737-3-stefanha@redhat.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  util/vhost-user-server.c | 2 +-
 file changed, 1 insertion(+), 1 deletion(-)
 diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/util/vhost-user-server.c
 +++ b/util/vhost-user-server.c
 @@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
          return false;
      }
 -    /* zero out unspecified fileds */
 +    /* zero out unspecified fields */
      *server = (VuServer) {
          .listener              = listener,
          .vu_iface              = vu_iface,
 --
 .26.2

-[PULL v2 10/30] util/vhost-user-server: drop unnecessary QOM cast
+[PULL v2 09/28] util/vhost-user-server: drop unnecessary QOM cast
 We already have access to the value with the correct type (ioc and sioc
 are the same QIOChannel).
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Message-id: 20200924151549.913737-4-stefanha@redhat.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  util/vhost-user-server.c | 2 +-
 file changed, 1 insertion(+), 1 deletion(-)
 diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/util/vhost-user-server.c
 +++ b/util/vhost-user-server.c
 @@ -XXX,XX +XXX,XX @@ static void vu_accept(QIONetListener *listener, QIOChannelSocket *sioc,
      server->ioc = QIO_CHANNEL(sioc);
      object_ref(OBJECT(server->ioc));
      qio_channel_attach_aio_context(server->ioc, server->ctx);
 -    qio_channel_set_blocking(QIO_CHANNEL(server->sioc), false, NULL);
 +    qio_channel_set_blocking(server->ioc, false, NULL);
      vu_client_start(server);
  }
 --
 .26.2

-[PULL v2 11/30] util/vhost-user-server: drop unnecessary watch deletion
+[PULL v2 10/28] util/vhost-user-server: drop unnecessary watch deletion
 Explicitly deleting watches is not necessary since libvhost-user calls
 remove_watch() during vu_deinit(). Add an assertion to check this
 though.
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Message-id: 20200924151549.913737-5-stefanha@redhat.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  util/vhost-user-server.c | 19 ++++---------------
 file changed, 4 insertions(+), 15 deletions(-)
 diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/util/vhost-user-server.c
 +++ b/util/vhost-user-server.c
 @@ -XXX,XX +XXX,XX @@ static void close_client(VuServer *server)
      /* When this is set vu_client_trip will stop new processing vhost-user message */
      server->sioc = NULL;
 -    VuFdWatch *vu_fd_watch, *next;
 -    QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
 -        aio_set_fd_handler(server->ioc->ctx, vu_fd_watch->fd, true, NULL,
 -                           NULL, NULL, NULL);
 -    }
 -
 -    while (!QTAILQ_EMPTY(&server->vu_fd_watches)) {
 -        QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
 -            if (!vu_fd_watch->processing) {
 -                QTAILQ_REMOVE(&server->vu_fd_watches, vu_fd_watch, next);
 -                g_free(vu_fd_watch);
 -            }
 -        }
 -    }
 -
      while (server->processing_msg) {
          if (server->ioc->read_coroutine) {
              server->ioc->read_coroutine = NULL;
 @@ -XXX,XX +XXX,XX @@ static void close_client(VuServer *server)
      }
      vu_deinit(&server->vu_dev);
 +
 +    /* vu_deinit() should have called remove_watch() */
 +    assert(QTAILQ_EMPTY(&server->vu_fd_watches));
 +
      object_unref(OBJECT(sioc));
      object_unref(OBJECT(server->ioc));
  }
 --
 .26.2

-[PULL v2 12/30] block/export: consolidate request structs into VuBlockReq
+[PULL v2 11/28] block/export: consolidate request structs into VuBlockReq
 Only one struct is needed per request. Drop req_data and the separate
 VuBlockReq instance. Instead let vu_queue_pop() allocate everything at
 once.
 This fixes the req_data memory leak in vu_block_virtio_process_req().
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Message-id: 20200924151549.913737-6-stefanha@redhat.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  block/export/vhost-user-blk-server.c | 68 +++++++++-------------------
 file changed, 21 insertions(+), 47 deletions(-)
 diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/export/vhost-user-blk-server.c
 +++ b/block/export/vhost-user-blk-server.c
 @@ -XXX,XX +XXX,XX @@ struct virtio_blk_inhdr {
  };
  typedef struct VuBlockReq {
 -    VuVirtqElement *elem;
 +    VuVirtqElement elem;
      int64_t sector_num;
      size_t size;
      struct virtio_blk_inhdr *in;
 @@ -XXX,XX +XXX,XX @@ static void vu_block_req_complete(VuBlockReq *req)
      VuDev *vu_dev = &req->server->vu_dev;
      /* IO size with 1 extra status byte */
 -    vu_queue_push(vu_dev, req->vq, req->elem, req->size + 1);
 +    vu_queue_push(vu_dev, req->vq, &req->elem, req->size + 1);
      vu_queue_notify(vu_dev, req->vq);
 -    if (req->elem) {
 -        free(req->elem);
 -    }
 -
 -    g_free(req);
 +    free(req);
  }
  static VuBlockDev *get_vu_block_device_by_server(VuServer *server)
 @@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_flush(VuBlockReq *req)
      blk_co_flush(backend);
  }
 -struct req_data {
 -    VuServer *server;
 -    VuVirtq *vq;
 -    VuVirtqElement *elem;
 -};
 -
  static void coroutine_fn vu_block_virtio_process_req(void *opaque)
  {
 -    struct req_data *data = opaque;
 -    VuServer *server = data->server;
 -    VuVirtq *vq = data->vq;
 -    VuVirtqElement *elem = data->elem;
 +    VuBlockReq *req = opaque;
 +    VuServer *server = req->server;
 +    VuVirtqElement *elem = &req->elem;
      uint32_t type;
 -    VuBlockReq *req;
      VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
      BlockBackend *backend = vdev_blk->backend;
 @@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
      struct iovec *out_iov = elem->out_sg;
      unsigned in_num = elem->in_num;
      unsigned out_num = elem->out_num;
 +
      /* refer to hw/block/virtio_blk.c */
      if (elem->out_num < 1 || elem->in_num < 1) {
          error_report("virtio-blk request missing headers");
 -        free(elem);
 -        return;
 +        goto err;
      }
 -    req = g_new0(VuBlockReq, 1);
 -    req->server = server;
 -    req->vq = vq;
 -    req->elem = elem;
 -
      if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out,
                              sizeof(req->out)) != sizeof(req->out))) {
          error_report("virtio-blk request outhdr too short");
 @@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
  err:
      free(elem);
 -    g_free(req);
 -    return;
  }
  static void vu_block_process_vq(VuDev *vu_dev, int idx)
  {
 -    VuServer *server;
 -    VuVirtq *vq;
 -    struct req_data *req_data;
 +    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
 +    VuVirtq *vq = vu_get_queue(vu_dev, idx);
 -    server = container_of(vu_dev, VuServer, vu_dev);
 -    assert(server);
 -
 -    vq = vu_get_queue(vu_dev, idx);
 -    assert(vq);
 -    VuVirtqElement *elem;
      while (1) {
 -        elem = vu_queue_pop(vu_dev, vq, sizeof(VuVirtqElement) +
 -                                    sizeof(VuBlockReq));
 -        if (elem) {
 -            req_data = g_new0(struct req_data, 1);
 -            req_data->server = server;
 -            req_data->vq = vq;
 -            req_data->elem = elem;
 -            Coroutine *co = qemu_coroutine_create(vu_block_virtio_process_req,
 -                                                  req_data);
 -            aio_co_enter(server->ioc->ctx, co);
 -        } else {
 +        VuBlockReq *req;
 +
 +        req = vu_queue_pop(vu_dev, vq, sizeof(VuBlockReq));
 +        if (!req) {
              break;
          }
 +
 +        req->server = server;
 +        req->vq = vq;
 +
 +        Coroutine *co =
 +            qemu_coroutine_create(vu_block_virtio_process_req, req);
 +        qemu_coroutine_enter(co);
      }
  }
 --
 .26.2

-[PULL v2 13/30] util/vhost-user-server: drop unused DevicePanicNotifier
+[PULL v2 12/28] util/vhost-user-server: drop unused DevicePanicNotifier
 The device panic notifier callback is not used. Drop it.
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Message-id: 20200924151549.913737-7-stefanha@redhat.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  util/vhost-user-server.h             | 3 ---
  block/export/vhost-user-blk-server.c | 3 +--
  util/vhost-user-server.c             | 6 ------
 files changed, 1 insertion(+), 11 deletions(-)
 diff --git a/util/vhost-user-server.h b/util/vhost-user-server.h
 index XXXXXXX..XXXXXXX 100644
 --- a/util/vhost-user-server.h
 +++ b/util/vhost-user-server.h
 @@ -XXX,XX +XXX,XX @@ typedef struct VuFdWatch {
  } VuFdWatch;
  typedef struct VuServer VuServer;
 -typedef void DevicePanicNotifierFn(VuServer *server);
  struct VuServer {
      QIONetListener *listener;
      AioContext *ctx;
 -    DevicePanicNotifierFn *device_panic_notifier;
      int max_queues;
      const VuDevIface *vu_iface;
      VuDev vu_dev;
 @@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
                               SocketAddress *unix_socket,
                               AioContext *ctx,
                               uint16_t max_queues,
 -                             DevicePanicNotifierFn *device_panic_notifier,
                               const VuDevIface *vu_iface,
                               Error **errp);
 diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/export/vhost-user-blk-server.c
 +++ b/block/export/vhost-user-blk-server.c
 @@ -XXX,XX +XXX,XX @@ static void vhost_user_blk_server_start(VuBlockDev *vu_block_device,
      ctx = bdrv_get_aio_context(blk_bs(vu_block_device->backend));
      if (!vhost_user_server_start(&vu_block_device->vu_server, addr, ctx,
 -                                 VHOST_USER_BLK_MAX_QUEUES,
 -                                 NULL, &vu_block_iface,
 +                                 VHOST_USER_BLK_MAX_QUEUES, &vu_block_iface,
                                   errp)) {
          goto error;
      }
 diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/util/vhost-user-server.c
 +++ b/util/vhost-user-server.c
 @@ -XXX,XX +XXX,XX @@ static void panic_cb(VuDev *vu_dev, const char *buf)
          close_client(server);
      }
 -    if (server->device_panic_notifier) {
 -        server->device_panic_notifier(server);
 -    }
 -
      /*
       * Set the callback function for network listener so another
       * vhost-user client can connect to this server
 @@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
                               SocketAddress *socket_addr,
                               AioContext *ctx,
                               uint16_t max_queues,
 -                             DevicePanicNotifierFn *device_panic_notifier,
                               const VuDevIface *vu_iface,
                               Error **errp)
  {
 @@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
          .vu_iface              = vu_iface,
          .max_queues            = max_queues,
          .ctx                   = ctx,
 -        .device_panic_notifier = device_panic_notifier,
      };
      qio_net_listener_set_name(server->listener, "vhost-user-backend-listener");
 --
 .26.2

-[PULL v2 14/30] util/vhost-user-server: fix memory leak in vu_message_read()
+[PULL v2 13/28] util/vhost-user-server: fix memory leak in vu_message_read()
 ...
 -            if (nfds + nfds_t > max_fds) {
 +
 +        if (nfds > 0) {
 +            if (vmsg->fd_num + nfds > max_fds) {
                  error_report("A maximum of %zu fds are allowed, "
-                              "however got %lu fds now",
+                              "however got %zu fds now",
 -                             max_fds, nfds + nfds_t);
 +                             max_fds, vmsg->fd_num + nfds);
 +                g_free(fds);
                  goto fail;
              }
 ...

-[PULL v2 15/30] util/vhost-user-server: check EOF when reading payload
+[PULL v2 14/28] util/vhost-user-server: check EOF when reading payload
 Unexpected EOF is an error that must be reported.
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Message-id: 20200924151549.913737-9-stefanha@redhat.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  util/vhost-user-server.c | 6 ++++--
 file changed, 4 insertions(+), 2 deletions(-)
 diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/util/vhost-user-server.c
 +++ b/util/vhost-user-server.c
 @@ -XXX,XX +XXX,XX @@ vu_message_read(VuDev *vu_dev, int conn_fd, VhostUserMsg *vmsg)
      };
      if (vmsg->size) {
          rc = qio_channel_readv_all_eof(ioc, &iov_payload, 1, &local_err);
 -        if (rc == -1) {
 -            error_report_err(local_err);
 +        if (rc != 1) {
 +            if (local_err) {
 +                error_report_err(local_err);
 +            }
              goto fail;
          }
      }
 --
 .26.2

-[PULL v2 16/30] util/vhost-user-server: rework vu_client_trip() coroutine lifecycle
+[PULL v2 15/28] util/vhost-user-server: rework vu_client_trip() coroutine lifecycle
 The vu_client_trip() coroutine is leaked during AioContext switching. It
 is also unsafe to destroy the vu_dev in panic_cb() since its callers
 still access it in some cases.
 Rework the lifecycle to solve these safety issues.
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Message-id: 20200924151549.913737-10-stefanha@redhat.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  util/vhost-user-server.h             |  29 ++--
  block/export/vhost-user-blk-server.c |   9 +-
  util/vhost-user-server.c             | 245 +++++++++++++++------------
 files changed, 155 insertions(+), 128 deletions(-)
 diff --git a/util/vhost-user-server.h b/util/vhost-user-server.h
 index XXXXXXX..XXXXXXX 100644
 --- a/util/vhost-user-server.h
 +++ b/util/vhost-user-server.h
 @@ -XXX,XX +XXX,XX @@
  #include "qapi/error.h"
  #include "standard-headers/linux/virtio_blk.h"
 +/* A kick fd that we monitor on behalf of libvhost-user */
  typedef struct VuFdWatch {
      VuDev *vu_dev;
      int fd; /*kick fd*/
      void *pvt;
      vu_watch_cb cb;
 -    bool processing;
      QTAILQ_ENTRY(VuFdWatch) next;
  } VuFdWatch;
 -typedef struct VuServer VuServer;
 -
 -struct VuServer {
 +/**
 + * VuServer:
 + * A vhost-user server instance with user-defined VuDevIface callbacks.
 + * Vhost-user device backends can be implemented using VuServer. VuDevIface
 + * callbacks and virtqueue kicks run in the given AioContext.
 + */
 +typedef struct {
      QIONetListener *listener;
 +    QEMUBH *restart_listener_bh;
      AioContext *ctx;
      int max_queues;
      const VuDevIface *vu_iface;
 +
 +    /* Protected by ctx lock */
      VuDev vu_dev;
      QIOChannel *ioc; /* The I/O channel with the client */
      QIOChannelSocket *sioc; /* The underlying data channel with the client */
 -    /* IOChannel for fd provided via VHOST_USER_SET_SLAVE_REQ_FD */
 -    QIOChannel *ioc_slave;
 -    QIOChannelSocket *sioc_slave;
 -    Coroutine *co_trip; /* coroutine for processing VhostUserMsg */
      QTAILQ_HEAD(, VuFdWatch) vu_fd_watches;
 -    /* restart coroutine co_trip if AIOContext is changed */
 -    bool aio_context_changed;
 -    bool processing_msg;
 -};
 +
 +    Coroutine *co_trip; /* coroutine for processing VhostUserMsg */
 +} VuServer;
  bool vhost_user_server_start(VuServer *server,
                               SocketAddress *unix_socket,
 @@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
  void vhost_user_server_stop(VuServer *server);
 -void vhost_user_server_set_aio_context(VuServer *server, AioContext *ctx);
 +void vhost_user_server_attach_aio_context(VuServer *server, AioContext *ctx);
 +void vhost_user_server_detach_aio_context(VuServer *server);
  #endif /* VHOST_USER_SERVER_H */
 diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/export/vhost-user-blk-server.c
 +++ b/block/export/vhost-user-blk-server.c
 @@ -XXX,XX +XXX,XX @@ static const VuDevIface vu_block_iface = {
  static void blk_aio_attached(AioContext *ctx, void *opaque)
  {
      VuBlockDev *vub_dev = opaque;
 -    aio_context_acquire(ctx);
 -    vhost_user_server_set_aio_context(&vub_dev->vu_server, ctx);
 -    aio_context_release(ctx);
 +    vhost_user_server_attach_aio_context(&vub_dev->vu_server, ctx);
  }
  static void blk_aio_detach(void *opaque)
  {
      VuBlockDev *vub_dev = opaque;
 -    AioContext *ctx = vub_dev->vu_server.ctx;
 -    aio_context_acquire(ctx);
 -    vhost_user_server_set_aio_context(&vub_dev->vu_server, NULL);
 -    aio_context_release(ctx);
 +    vhost_user_server_detach_aio_context(&vub_dev->vu_server);
  }
  static void
 diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/util/vhost-user-server.c
 +++ b/util/vhost-user-server.c
 @@ -XXX,XX +XXX,XX @@
   */
  #include "qemu/osdep.h"
  #include "qemu/main-loop.h"
 +#include "block/aio-wait.h"
  #include "vhost-user-server.h"
 +/*
 + * Theory of operation:
 + *
 + * VuServer is started and stopped by vhost_user_server_start() and
 + * vhost_user_server_stop() from the main loop thread. Starting the server
 + * opens a vhost-user UNIX domain socket and listens for incoming connections.
 + * Only one connection is allowed at a time.
 + *
 + * The connection is handled by the vu_client_trip() coroutine in the
 + * VuServer->ctx AioContext. The coroutine consists of a vu_dispatch() loop
 + * where libvhost-user calls vu_message_read() to receive the next vhost-user
 + * protocol messages over the UNIX domain socket.
 + *
 + * When virtqueues are set up libvhost-user calls set_watch() to monitor kick
 + * fds. These fds are also handled in the VuServer->ctx AioContext.
 + *
 + * Both vu_client_trip() and kick fd monitoring can be stopped by shutting down
 + * the socket connection. Shutting down the socket connection causes
 + * vu_message_read() to fail since no more data can be received from the socket.
 + * After vu_dispatch() fails, vu_client_trip() calls vu_deinit() to stop
 + * libvhost-user before terminating the coroutine. vu_deinit() calls
 + * remove_watch() to stop monitoring kick fds and this stops virtqueue
 + * processing.
 + *
 + * When vu_client_trip() has finished cleaning up it schedules a BH in the main
 + * loop thread to accept the next client connection.
 + *
 + * When libvhost-user detects an error it calls panic_cb() and sets the
 + * dev->broken flag. Both vu_client_trip() and kick fd processing stop when
 + * the dev->broken flag is set.
 + *
 + * It is possible to switch AioContexts using
 + * vhost_user_server_detach_aio_context() and
 + * vhost_user_server_attach_aio_context(). They stop monitoring fds in the old
 + * AioContext and resume monitoring in the new AioContext. The vu_client_trip()
 + * coroutine remains in a yielded state during the switch. This is made
 + * possible by QIOChannel's support for spurious coroutine re-entry in
 + * qio_channel_yield(). The coroutine will restart I/O when re-entered from the
 + * new AioContext.
 + */
 +
  static void vmsg_close_fds(VhostUserMsg *vmsg)
  {
      int i;
 @@ -XXX,XX +XXX,XX @@ static void vmsg_unblock_fds(VhostUserMsg *vmsg)
      }
  }
 -static void vu_accept(QIONetListener *listener, QIOChannelSocket *sioc,
 -                      gpointer opaque);
 -
 -static void close_client(VuServer *server)
 -{
 -    /*
 -     * Before closing the client
 -     *
 -     * 1. Let vu_client_trip stop processing new vhost-user msg
 -     *
 -     * 2. remove kick_handler
 -     *
 -     * 3. wait for the kick handler to be finished
 -     *
 -     * 4. wait for the current vhost-user msg to be finished processing
 -     */
 -
 -    QIOChannelSocket *sioc = server->sioc;
 -    /* When this is set vu_client_trip will stop new processing vhost-user message */
 -    server->sioc = NULL;
 -
 -    while (server->processing_msg) {
 -        if (server->ioc->read_coroutine) {
 -            server->ioc->read_coroutine = NULL;
 -            qio_channel_set_aio_fd_handler(server->ioc, server->ioc->ctx, NULL,
 -                                           NULL, server->ioc);
 -            server->processing_msg = false;
 -        }
 -    }
 -
 -    vu_deinit(&server->vu_dev);
 -
 -    /* vu_deinit() should have called remove_watch() */
 -    assert(QTAILQ_EMPTY(&server->vu_fd_watches));
 -
 -    object_unref(OBJECT(sioc));
 -    object_unref(OBJECT(server->ioc));
 -}
 -
  static void panic_cb(VuDev *vu_dev, const char *buf)
  {
 -    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
 -
 -    /* avoid while loop in close_client */
 -    server->processing_msg = false;
 -
 -    if (buf) {
 -        error_report("vu_panic: %s", buf);
 -    }
 -
 -    if (server->sioc) {
 -        close_client(server);
 -    }
 -
 -    /*
 -     * Set the callback function for network listener so another
 -     * vhost-user client can connect to this server
 -     */
 -    qio_net_listener_set_client_func(server->listener,
 -                                     vu_accept,
 -                                     server,
 -                                     NULL);
 +    error_report("vu_panic: %s", buf);
  }
  static bool coroutine_fn
 @@ -XXX,XX +XXX,XX @@ fail:
      return false;
  }
 -
 -static void vu_client_start(VuServer *server);
  static coroutine_fn void vu_client_trip(void *opaque)
  {
      VuServer *server = opaque;
 +    VuDev *vu_dev = &server->vu_dev;
 -    while (!server->aio_context_changed && server->sioc) {
 -        server->processing_msg = true;
 -        vu_dispatch(&server->vu_dev);
 -        server->processing_msg = false;
 +    while (!vu_dev->broken && vu_dispatch(vu_dev)) {
 +        /* Keep running */
      }
 -    if (server->aio_context_changed && server->sioc) {
 -        server->aio_context_changed = false;
 -        vu_client_start(server);
 -    }
 -}
 +    vu_deinit(vu_dev);
 +
 +    /* vu_deinit() should have called remove_watch() */
 +    assert(QTAILQ_EMPTY(&server->vu_fd_watches));
 +
 +    object_unref(OBJECT(server->sioc));
 +    server->sioc = NULL;
 -static void vu_client_start(VuServer *server)
 -{
 -    server->co_trip = qemu_coroutine_create(vu_client_trip, server);
 -    aio_co_enter(server->ctx, server->co_trip);
 +    object_unref(OBJECT(server->ioc));
 +    server->ioc = NULL;
 +
 +    server->co_trip = NULL;
 +    if (server->restart_listener_bh) {
 +        qemu_bh_schedule(server->restart_listener_bh);
 +    }
 +    aio_wait_kick();
  }
  /*
 @@ -XXX,XX +XXX,XX @@ static void vu_client_start(VuServer *server)
  static void kick_handler(void *opaque)
  {
      VuFdWatch *vu_fd_watch = opaque;
 -    vu_fd_watch->processing = true;
 -    vu_fd_watch->cb(vu_fd_watch->vu_dev, 0, vu_fd_watch->pvt);
 -    vu_fd_watch->processing = false;
 +    VuDev *vu_dev = vu_fd_watch->vu_dev;
 +
 +    vu_fd_watch->cb(vu_dev, 0, vu_fd_watch->pvt);
 +
 +    /* Stop vu_client_trip() if an error occurred in vu_fd_watch->cb() */
 +    if (vu_dev->broken) {
 +        VuServer *server = container_of(vu_dev, VuServer, vu_dev);
 +
 +        qio_channel_shutdown(server->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
 +    }
  }
 -
  static VuFdWatch *find_vu_fd_watch(VuServer *server, int fd)
  {
 @@ -XXX,XX +XXX,XX @@ static void vu_accept(QIONetListener *listener, QIOChannelSocket *sioc,
      qio_channel_set_name(QIO_CHANNEL(sioc), "vhost-user client");
      server->ioc = QIO_CHANNEL(sioc);
      object_ref(OBJECT(server->ioc));
 -    qio_channel_attach_aio_context(server->ioc, server->ctx);
 +
 +    /* TODO vu_message_write() spins if non-blocking! */
      qio_channel_set_blocking(server->ioc, false, NULL);
 -    vu_client_start(server);
 +
 +    server->co_trip = qemu_coroutine_create(vu_client_trip, server);
 +
 +    aio_context_acquire(server->ctx);
 +    vhost_user_server_attach_aio_context(server, server->ctx);
 +    aio_context_release(server->ctx);
  }
 -
  void vhost_user_server_stop(VuServer *server)
  {
 +    aio_context_acquire(server->ctx);
 +
 +    qemu_bh_delete(server->restart_listener_bh);
 +    server->restart_listener_bh = NULL;
 +
      if (server->sioc) {
 -        close_client(server);
 +        VuFdWatch *vu_fd_watch;
 +
 +        QTAILQ_FOREACH(vu_fd_watch, &server->vu_fd_watches, next) {
 +            aio_set_fd_handler(server->ctx, vu_fd_watch->fd, true,
 +                               NULL, NULL, NULL, vu_fd_watch);
 +        }
 +
 +        qio_channel_shutdown(server->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
 +
 +        AIO_WAIT_WHILE(server->ctx, server->co_trip);
      }
 +    aio_context_release(server->ctx);
 +
      if (server->listener) {
          qio_net_listener_disconnect(server->listener);
          object_unref(OBJECT(server->listener));
      }
 +}
 +
 +/*
 + * Allow the next client to connect to the server. Called from a BH in the main
 + * loop.
 + */
 +static void restart_listener_bh(void *opaque)
 +{
 +    VuServer *server = opaque;
 +    qio_net_listener_set_client_func(server->listener, vu_accept, server,
 +                                     NULL);
  }
 -void vhost_user_server_set_aio_context(VuServer *server, AioContext *ctx)
 +/* Called with ctx acquired */
 +void vhost_user_server_attach_aio_context(VuServer *server, AioContext *ctx)
  {
 -    VuFdWatch *vu_fd_watch, *next;
 -    void *opaque = NULL;
 -    IOHandler *io_read = NULL;
 -    bool attach;
 +    VuFdWatch *vu_fd_watch;
 -    server->ctx = ctx ? ctx : qemu_get_aio_context();
 +    server->ctx = ctx;
      if (!server->sioc) {
 -        /* not yet serving any client*/
          return;
      }
 -    if (ctx) {
 -        qio_channel_attach_aio_context(server->ioc, ctx);
 -        server->aio_context_changed = true;
 -        io_read = kick_handler;
 -        attach = true;
 -    } else {
 +    qio_channel_attach_aio_context(server->ioc, ctx);
 +
 +    QTAILQ_FOREACH(vu_fd_watch, &server->vu_fd_watches, next) {
 +        aio_set_fd_handler(ctx, vu_fd_watch->fd, true, kick_handler, NULL,
 +                           NULL, vu_fd_watch);
 +    }
 +
 +    aio_co_schedule(ctx, server->co_trip);
 +}
 +
 +/* Called with server->ctx acquired */
 +void vhost_user_server_detach_aio_context(VuServer *server)
 +{
 +    if (server->sioc) {
 +        VuFdWatch *vu_fd_watch;
 +
 +        QTAILQ_FOREACH(vu_fd_watch, &server->vu_fd_watches, next) {
 +            aio_set_fd_handler(server->ctx, vu_fd_watch->fd, true,
 +                               NULL, NULL, NULL, vu_fd_watch);
 +        }
 +
          qio_channel_detach_aio_context(server->ioc);
 -        /* server->ioc->ctx keeps the old AioConext */
 -        ctx = server->ioc->ctx;
 -        attach = false;
      }
 -    QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
 -        if (vu_fd_watch->cb) {
 -            opaque = attach ? vu_fd_watch : NULL;
 -            aio_set_fd_handler(ctx, vu_fd_watch->fd, true,
 -                               io_read, NULL, NULL,
 -                               opaque);
 -        }
 -    }
 +    server->ctx = NULL;
  }
 -
  bool vhost_user_server_start(VuServer *server,
                               SocketAddress *socket_addr,
                               AioContext *ctx,
 @@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
                               const VuDevIface *vu_iface,
                               Error **errp)
  {
 +    QEMUBH *bh;
      QIONetListener *listener = qio_net_listener_new();
      if (qio_net_listener_open_sync(listener, socket_addr, 1,
                                     errp) < 0) {
 @@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
          return false;
      }
 +    bh = qemu_bh_new(restart_listener_bh, server);
 +
      /* zero out unspecified fields */
      *server = (VuServer) {
          .listener              = listener,
 +        .restart_listener_bh   = bh,
          .vu_iface              = vu_iface,
          .max_queues            = max_queues,
          .ctx                   = ctx,
 --
 .26.2

-[PULL v2 17/30] block/export: report flush errors
+[PULL v2 16/28] block/export: report flush errors
 Propagate the flush return value since errors are possible.
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Message-id: 20200924151549.913737-11-stefanha@redhat.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  block/export/vhost-user-blk-server.c | 11 +++++++----
 file changed, 7 insertions(+), 4 deletions(-)
 diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/export/vhost-user-blk-server.c
 +++ b/block/export/vhost-user-blk-server.c
 @@ -XXX,XX +XXX,XX @@ vu_block_discard_write_zeroes(VuBlockReq *req, struct iovec *iov,
      return -EINVAL;
  }
 -static void coroutine_fn vu_block_flush(VuBlockReq *req)
 +static int coroutine_fn vu_block_flush(VuBlockReq *req)
  {
      VuBlockDev *vdev_blk = get_vu_block_device_by_server(req->server);
      BlockBackend *backend = vdev_blk->backend;
 -    blk_co_flush(backend);
 +    return blk_co_flush(backend);
  }
  static void coroutine_fn vu_block_virtio_process_req(void *opaque)
 @@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
          break;
      }
      case VIRTIO_BLK_T_FLUSH:
 -        vu_block_flush(req);
 -        req->in->status = VIRTIO_BLK_S_OK;
 +        if (vu_block_flush(req) == 0) {
 +            req->in->status = VIRTIO_BLK_S_OK;
 +        } else {
 +            req->in->status = VIRTIO_BLK_S_IOERR;
 +        }
          break;
      case VIRTIO_BLK_T_GET_ID: {
          size_t size = MIN(iov_size(&elem->in_sg[0], in_num),
 --
 .26.2

-[PULL v2 18/30] block/export: convert vhost-user-blk server to block export API
+[PULL v2 17/28] block/export: convert vhost-user-blk server to block export API
 ...
 QAPI 'features' syntax can be used to advertize them.
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Acked-by: Markus Armbruster <armbru@redhat.com>
 Message-id: 20200924151549.913737-12-stefanha@redhat.com
+[Skip test on big-endian host architectures because this device doesn't
+support them yet (as already mentioned in a code comment).
+--Stefan]
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  qapi/block-export.json               |  21 +-
  block/export/vhost-user-blk-server.h |  23 +-
  block/export/export.c                |   6 +
  block/export/vhost-user-blk-server.c | 452 +++++++--------------------
- tests/qtest/vhost-user-blk-test.c    |   2 +-
  util/vhost-user-server.c             |  10 +-
  block/export/meson.build             |   1 +
  block/meson.build                    |   1 -
-files changed, 157 insertions(+), 359 deletions(-)
+files changed, 156 insertions(+), 358 deletions(-)
 diff --git a/qapi/block-export.json b/qapi/block-export.json
 index XXXXXXX..XXXXXXX 100644
 --- a/qapi/block-export.json
 +++ b/qapi/block-export.json
 ...
 -{
 -    type_register_static(&vhost_user_blk_server_info);
 -}
 -
 -type_init(vhost_user_blk_server_register_types)
-diff --git a/tests/qtest/vhost-user-blk-test.c b/tests/qtest/vhost-user-blk-test.c
-index XXXXXXX..XXXXXXX 100644
---- a/tests/qtest/vhost-user-blk-test.c
-+++ b/tests/qtest/vhost-user-blk-test.c
-@@ -XXX,XX +XXX,XX @@ static char *start_vhost_user_blk(GString *cmd_line, int vus_instances)
-         img_path = drive_create();
-         g_string_append_printf(storage_daemon_command,
-             "--blockdev driver=file,node-name=disk%d,filename=%s "
--            "--object vhost-user-blk-server,id=disk%d,unix-socket=%s,"
-+            "--export type=vhost-user-blk,id=disk%d,addr.type=unix,addr.path=%s,"
-             "node-name=disk%i,writable=on ",
-             i, img_path, i, sock_path, i);
 diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/util/vhost-user-server.c
 +++ b/util/vhost-user-server.c
 @@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
 ...

-[PULL v2 19/30] util/vhost-user-server: move header to include/
+[PULL v2 18/28] util/vhost-user-server: move header to include/
 ...
  S: Maintained
  F: block/export/vhost-user-blk-server.c
 -F: util/vhost-user-server.c
 +F: block/export/vhost-user-blk-server.h
 +F: include/qemu/vhost-user-server.h
- F: tests/qtest/vhost-user-blk-test.c
  F: tests/qtest/libqos/vhost-user-blk.c
 +F: util/vhost-user-server.c
  Replication
  M: Wen Congyang <wencongyang2@huawei.com>
 ...

-[PULL v2 20/30] util/vhost-user-server: use static library in meson.build
+[PULL v2 19/28] util/vhost-user-server: use static library in meson.build
 ...
 Also switch from CONFIG_LINUX to CONFIG_VHOST_USER, which is what the
 vhost-user tools (vhost-user-gpu, etc) do.
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Message-id: 20200924151549.913737-14-stefanha@redhat.com
+[Added CONFIG_LINUX again because libvhost-user doesn't build on macOS.
+--Stefan]
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  block/export/export.c             | 8 ++++----
  block/export/meson.build          | 2 +-
  contrib/libvhost-user/meson.build | 1 +
  meson.build                       | 6 +++++-
- tests/qtest/meson.build           | 2 +-
  util/meson.build                  | 4 +++-
-files changed, 15 insertions(+), 8 deletions(-)
+files changed, 14 insertions(+), 7 deletions(-)
 diff --git a/block/export/export.c b/block/export/export.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/export/export.c
 +++ b/block/export/export.c
 ...
 --- a/block/export/meson.build
 +++ b/block/export/meson.build
 @@ -XXX,XX +XXX,XX @@
  block_ss.add(files('export.c'))
 -block_ss.add(when: 'CONFIG_LINUX', if_true: files('vhost-user-blk-server.c', '../../contrib/libvhost-user/libvhost-user.c'))
-+block_ss.add(when: 'CONFIG_VHOST_USER', if_true: files('vhost-user-blk-server.c'))
++block_ss.add(when: ['CONFIG_LINUX', 'CONFIG_VHOST_USER'], if_true: files('vhost-user-blk-server.c'))
 diff --git a/contrib/libvhost-user/meson.build b/contrib/libvhost-user/meson.build
 index XXXXXXX..XXXXXXX 100644
 --- a/contrib/libvhost-user/meson.build
 +++ b/contrib/libvhost-user/meson.build
 @@ -XXX,XX +XXX,XX @@
 ...
    if 'CONFIG_VHOST_USER' in config_host
 -    subdir('contrib/libvhost-user')
      subdir('contrib/vhost-user-blk')
      subdir('contrib/vhost-user-gpu')
      subdir('contrib/vhost-user-input')
-diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
-index XXXXXXX..XXXXXXX 100644
---- a/tests/qtest/meson.build
-+++ b/tests/qtest/meson.build
-@@ -XXX,XX +XXX,XX @@ qos_test_ss.add(
- )
- qos_test_ss.add(when: 'CONFIG_VIRTFS', if_true: files('virtio-9p-test.c'))
- qos_test_ss.add(when: 'CONFIG_VHOST_USER', if_true: files('vhost-user-test.c'))
--qos_test_ss.add(when: ['CONFIG_LINUX', 'CONFIG_TOOLS'], if_true: files('vhost-user-blk-test.c'))
-+qos_test_ss.add(when: ['CONFIG_VHOST_USER', 'CONFIG_TOOLS'], if_true: files('vhost-user-blk-test.c'))
- extra_qtest_deps = {
-   'bios-tables-test': [io],
 diff --git a/util/meson.build b/util/meson.build
 index XXXXXXX..XXXXXXX 100644
 --- a/util/meson.build
 +++ b/util/meson.build
 @@ -XXX,XX +XXX,XX @@ if have_block
    util_ss.add(files('main-loop.c'))
    util_ss.add(files('nvdimm-utils.c'))
    util_ss.add(files('qemu-coroutine.c', 'qemu-coroutine-lock.c', 'qemu-coroutine-io.c'))
 -  util_ss.add(when: 'CONFIG_LINUX', if_true: files('vhost-user-server.c'))
-+  util_ss.add(when: 'CONFIG_VHOST_USER', if_true: [
++  util_ss.add(when: ['CONFIG_LINUX', 'CONFIG_VHOST_USER'], if_true: [
 +    files('vhost-user-server.c'), vhost_user
 +  ])
    util_ss.add(files('block-helpers.c'))
    util_ss.add(files('qemu-coroutine-sleep.c'))
    util_ss.add(files('qemu-co-shared-resource.c'))
 --
 .26.2

-[PULL v2 21/30] qemu-storage-daemon: avoid compiling blockdev_ss twice
+[PULL v2 20/28] qemu-storage-daemon: avoid compiling blockdev_ss twice
 ...
 diff --git a/meson.build b/meson.build
 index XXXXXXX..XXXXXXX 100644
 --- a/meson.build
 +++ b/meson.build
 @@ -XXX,XX +XXX,XX @@ blockdev_ss.add(files(
+ # os-win32.c does not
  blockdev_ss.add(when: 'CONFIG_POSIX', if_true: files('os-posix.c'))
  softmmu_ss.add(when: 'CONFIG_WIN32', if_true: [files('os-win32.c')])
 -softmmu_ss.add_all(blockdev_ss)
- softmmu_ss.add(files(
-   'bootdevice.c',
+ common_ss.add(files('cpus-common.c'))
-   'dma-helpers.c',
 @@ -XXX,XX +XXX,XX @@ block = declare_dependency(link_whole: [libblock],
                             link_args: '@block.syms',
                             dependencies: [crypto, io])
 +blockdev_ss = blockdev_ss.apply(config_host, strict: false)
 ...

-[PULL v2 22/30] block: move block exports to libblockdev
+[PULL v2 21/28] block: move block exports to libblockdev
 ...
 Message-id: 20200929125516.186715-4-stefanha@redhat.com
 [Fixed s/ndb/nbd/ typo in commit description as suggested by Eric Blake
 --Stefan]
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
- qemu-nbd.c                | 25 +++++++++----------------
+ qemu-nbd.c                | 21 ++++++++-------------
  stubs/blk-exp-close-all.c |  7 +++++++
  block/export/meson.build  |  4 ++--
  meson.build               |  4 ++--
  nbd/meson.build           |  2 ++
  stubs/meson.build         |  1 +
-files changed, 23 insertions(+), 20 deletions(-)
+files changed, 22 insertions(+), 17 deletions(-)
  create mode 100644 stubs/blk-exp-close-all.c
 diff --git a/qemu-nbd.c b/qemu-nbd.c
 index XXXXXXX..XXXXXXX 100644
 --- a/qemu-nbd.c
 ...
 +#include "sysemu/runstate.h" /* for qemu_system_killed() prototype */
  #include "block/block_int.h"
  #include "block/nbd.h"
  #include "qemu/main-loop.h"
 @@ -XXX,XX +XXX,XX @@ QEMU_COPYRIGHT "\n"
-     , name);
  }
--#ifdef CONFIG_POSIX
+ #ifdef CONFIG_POSIX
 -static void termsig_handler(int signum)
-+#if CONFIG_POSIX
 +/*
 + * The client thread uses SIGTERM to interrupt the server.  A signal
 + * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
 + */
 +void qemu_system_killed(int signum, pid_t pid)
  {
      qatomic_cmpxchg(&state, RUNNING, TERMINATE);
      qemu_notify_event();
 @@ -XXX,XX +XXX,XX @@ int main(int argc, char **argv)
-     const char *pid_file_name = NULL;
      BlockExportOptions *export_opts;
--#ifdef CONFIG_POSIX
+ #ifdef CONFIG_POSIX
 -    /*
 -     * Exit gracefully on various signals, which includes SIGTERM used
 -     * by 'qemu-nbd -v -c'.
 -     */
 -    struct sigaction sa_sigterm;
 ...
 -    sigaction(SIGTERM, &sa_sigterm, NULL);
 -    sigaction(SIGINT, &sa_sigterm, NULL);
 -    sigaction(SIGHUP, &sa_sigterm, NULL);
 -
 -    signal(SIGPIPE, SIG_IGN);
--#endif
 +    os_setup_early_signal_handling();
 +    os_setup_signal_handling();
+ #endif
      socket_init();
-     error_init(argv[0]);
 diff --git a/stubs/blk-exp-close-all.c b/stubs/blk-exp-close-all.c
 new file mode 100644
 index XXXXXXX..XXXXXXX
 --- /dev/null
 +++ b/stubs/blk-exp-close-all.c
 ...
 index XXXXXXX..XXXXXXX 100644
 --- a/block/export/meson.build
 +++ b/block/export/meson.build
 @@ -XXX,XX +XXX,XX @@
 -block_ss.add(files('export.c'))
--block_ss.add(when: 'CONFIG_VHOST_USER', if_true: files('vhost-user-blk-server.c'))
+-block_ss.add(when: ['CONFIG_LINUX', 'CONFIG_VHOST_USER'], if_true: files('vhost-user-blk-server.c'))
 +blockdev_ss.add(files('export.c'))
-+blockdev_ss.add(when: 'CONFIG_VHOST_USER', if_true: files('vhost-user-blk-server.c'))
++blockdev_ss.add(when: ['CONFIG_LINUX', 'CONFIG_VHOST_USER'], if_true: files('vhost-user-blk-server.c'))
 diff --git a/meson.build b/meson.build
 index XXXXXXX..XXXXXXX 100644
 --- a/meson.build
 +++ b/meson.build
 @@ -XXX,XX +XXX,XX @@ subdir('dump')
 ...

-[PULL v2 23/30] block/export: add iothread and fixed-iothread options
+[PULL v2 22/28] block/export: add iothread and fixed-iothread options
 Make it possible to specify the iothread where the export will run. By
 default the block node can be moved to other AioContexts later and the
 export will follow. The fixed-iothread option forces strict behavior
 that prevents changing AioContext while the export is active. See the
 QAPI docs for details.
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Message-id: 20200929125516.186715-5-stefanha@redhat.com
 [Fix stray '#' character in block-export.json and add missing "(since:
 .2)" as suggested by Eric Blake.
 --Stefan]
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  qapi/block-export.json               | 11 ++++++++++
  block/export/export.c                | 31 +++++++++++++++++++++++++++-
  block/export/vhost-user-blk-server.c |  5 ++++-
  nbd/server.c                         |  2 --
 files changed, 45 insertions(+), 4 deletions(-)
 diff --git a/qapi/block-export.json b/qapi/block-export.json
 index XXXXXXX..XXXXXXX 100644
 --- a/qapi/block-export.json
 +++ b/qapi/block-export.json
 @@ -XXX,XX +XXX,XX @@
  #                export before completion is signalled. (since: 5.2;
  #                default: false)
  #
 +# @iothread: The name of the iothread object where the export will run. The
 +#            default is to use the thread currently associated with the
 +#            block node. (since: 5.2)
 +#
 +# @fixed-iothread: True prevents the block node from being moved to another
 +#                  thread while the export is active. If true and @iothread is
 +#                  given, export creation fails if the block node cannot be
 +#                  moved to the iothread. The default is false. (since: 5.2)
 +#
  # Since: 4.2
  ##
  { 'union': 'BlockExportOptions',
    'base': { 'type': 'BlockExportType',
              'id': 'str',
 +        '*fixed-iothread': 'bool',
 +        '*iothread': 'str',
              'node-name': 'str',
              '*writable': 'bool',
              '*writethrough': 'bool' },
 diff --git a/block/export/export.c b/block/export/export.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/export/export.c
 +++ b/block/export/export.c
 @@ -XXX,XX +XXX,XX @@
  #include "block/block.h"
  #include "sysemu/block-backend.h"
 +#include "sysemu/iothread.h"
  #include "block/export.h"
  #include "block/nbd.h"
  #include "qapi/error.h"
 @@ -XXX,XX +XXX,XX @@ static const BlockExportDriver *blk_exp_find_driver(BlockExportType type)
  BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
  {
 +    bool fixed_iothread = export->has_fixed_iothread && export->fixed_iothread;
      const BlockExportDriver *drv;
      BlockExport *exp = NULL;
      BlockDriverState *bs;
 -    BlockBackend *blk;
 +    BlockBackend *blk = NULL;
      AioContext *ctx;
      uint64_t perm;
      int ret;
 @@ -XXX,XX +XXX,XX @@ BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
      ctx = bdrv_get_aio_context(bs);
      aio_context_acquire(ctx);
 +    if (export->has_iothread) {
 +        IOThread *iothread;
 +        AioContext *new_ctx;
 +
 +        iothread = iothread_by_id(export->iothread);
 +        if (!iothread) {
 +            error_setg(errp, "iothread \"%s\" not found", export->iothread);
 +            goto fail;
 +        }
 +
 +        new_ctx = iothread_get_aio_context(iothread);
 +
 +        ret = bdrv_try_set_aio_context(bs, new_ctx, errp);
 +        if (ret == 0) {
 +            aio_context_release(ctx);
 +            aio_context_acquire(new_ctx);
 +            ctx = new_ctx;
 +        } else if (fixed_iothread) {
 +            goto fail;
 +        }
 +    }
 +
      /*
       * Block exports are used for non-shared storage migration. Make sure
       * that BDRV_O_INACTIVE is cleared and the image is ready for write
 @@ -XXX,XX +XXX,XX @@ BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
      }
      blk = blk_new(ctx, perm, BLK_PERM_ALL);
 +
 +    if (!fixed_iothread) {
 +        blk_set_allow_aio_context_change(blk, true);
 +    }
 +
      ret = blk_insert_bs(blk, bs, errp);
      if (ret < 0) {
          goto fail;
 diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/export/vhost-user-blk-server.c
 +++ b/block/export/vhost-user-blk-server.c
 @@ -XXX,XX +XXX,XX @@ static const VuDevIface vu_blk_iface = {
  static void blk_aio_attached(AioContext *ctx, void *opaque)
  {
      VuBlkExport *vexp = opaque;
 +
 +    vexp->export.ctx = ctx;
      vhost_user_server_attach_aio_context(&vexp->vu_server, ctx);
  }
  static void blk_aio_detach(void *opaque)
  {
      VuBlkExport *vexp = opaque;
 +
      vhost_user_server_detach_aio_context(&vexp->vu_server);
 +    vexp->export.ctx = NULL;
  }
  static void
 @@ -XXX,XX +XXX,XX @@ static int vu_blk_exp_create(BlockExport *exp, BlockExportOptions *opts,
      vu_blk_initialize_config(blk_bs(exp->blk), &vexp->blkcfg,
                                 logical_block_size);
 -    blk_set_allow_aio_context_change(exp->blk, true);
      blk_add_aio_context_notifier(exp->blk, blk_aio_attached, blk_aio_detach,
                                   vexp);
 diff --git a/nbd/server.c b/nbd/server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/nbd/server.c
 +++ b/nbd/server.c
 @@ -XXX,XX +XXX,XX @@ static int nbd_export_create(BlockExport *blk_exp, BlockExportOptions *exp_args,
          return ret;
      }
 -    blk_set_allow_aio_context_change(blk, true);
 -
      QTAILQ_INIT(&exp->clients);
      exp->name = g_strdup(arg->name);
      exp->description = g_strdup(arg->description);
 --
 .26.2

-[PULL v2 24/30] block/export: add vhost-user-blk multi-queue support
+[PULL v2 23/28] block/export: add vhost-user-blk multi-queue support
 Allow the number of queues to be configured using --export
 vhost-user-blk,num-queues=N. This setting should match the QEMU --device
 vhost-user-blk-pci,num-queues=N setting but QEMU vhost-user-blk.c lowers
 its own value if the vhost-user-blk backend offers fewer queues than
 QEMU.
 The vhost-user-blk-server.c code is already capable of multi-queue. All
 virtqueue processing runs in the same AioContext. No new locking is
 needed.
 Add the num-queues=N option and set the VIRTIO_BLK_F_MQ feature bit.
 Note that the feature bit only announces the presence of the num_queues
 configuration space field. It does not promise that there is more than 1
 virtqueue, so we can set it unconditionally.
 I tested multi-queue by running a random read fio test with numjobs=4 on
 an -smp 4 guest. After the benchmark finished the guest /proc/interrupts
 file showed activity on all 4 virtio-blk MSI-X. The /sys/block/vda/mq/
 directory shows that Linux blk-mq has 4 queues configured.
 An automated test is included in the next commit.
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Acked-by: Markus Armbruster <armbru@redhat.com>
 Message-id: 20201001144604.559733-2-stefanha@redhat.com
 [Fixed accidental tab characters as suggested by Markus Armbruster
 --Stefan]
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  qapi/block-export.json               | 10 +++++++---
  block/export/vhost-user-blk-server.c | 24 ++++++++++++++++++------
 files changed, 25 insertions(+), 9 deletions(-)
 diff --git a/qapi/block-export.json b/qapi/block-export.json
 index XXXXXXX..XXXXXXX 100644
 --- a/qapi/block-export.json
 +++ b/qapi/block-export.json
 @@ -XXX,XX +XXX,XX @@
  #        SocketAddress types are supported. Passed fds must be UNIX domain
  #        sockets.
  # @logical-block-size: Logical block size in bytes. Defaults to 512 bytes.
 +# @num-queues: Number of request virtqueues. Must be greater than 0. Defaults
 +#              to 1.
  #
  # Since: 5.2
  ##
  { 'struct': 'BlockExportOptionsVhostUserBlk',
 -  'data': { 'addr': 'SocketAddress', '*logical-block-size': 'size' } }
 +  'data': { 'addr': 'SocketAddress',
 +        '*logical-block-size': 'size',
 +            '*num-queues': 'uint16'} }
  ##
  # @NbdServerAddOptions:
 @@ -XXX,XX +XXX,XX @@
  { 'union': 'BlockExportOptions',
    'base': { 'type': 'BlockExportType',
              'id': 'str',
 -        '*fixed-iothread': 'bool',
 -        '*iothread': 'str',
 +            '*fixed-iothread': 'bool',
 +            '*iothread': 'str',
              'node-name': 'str',
              '*writable': 'bool',
              '*writethrough': 'bool' },
 diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/export/vhost-user-blk-server.c
 +++ b/block/export/vhost-user-blk-server.c
 @@ -XXX,XX +XXX,XX @@
  #include "util/block-helpers.h"
  enum {
 -    VHOST_USER_BLK_MAX_QUEUES = 1,
 +    VHOST_USER_BLK_NUM_QUEUES_DEFAULT = 1,
  };
  struct virtio_blk_inhdr {
      unsigned char status;
 @@ -XXX,XX +XXX,XX @@ static uint64_t vu_blk_get_features(VuDev *dev)
 ull << VIRTIO_BLK_F_DISCARD |
 ull << VIRTIO_BLK_F_WRITE_ZEROES |
 ull << VIRTIO_BLK_F_CONFIG_WCE |
 +               1ull << VIRTIO_BLK_F_MQ |
 ull << VIRTIO_F_VERSION_1 |
 ull << VIRTIO_RING_F_INDIRECT_DESC |
 ull << VIRTIO_RING_F_EVENT_IDX |
 @@ -XXX,XX +XXX,XX @@ static void blk_aio_detach(void *opaque)
  static void
  vu_blk_initialize_config(BlockDriverState *bs,
 -                           struct virtio_blk_config *config, uint32_t blk_size)
 +                         struct virtio_blk_config *config,
 +                         uint32_t blk_size,
 +                         uint16_t num_queues)
  {
      config->capacity = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
      config->blk_size = blk_size;
 @@ -XXX,XX +XXX,XX @@ vu_blk_initialize_config(BlockDriverState *bs,
      config->seg_max = 128 - 2;
      config->min_io_size = 1;
      config->opt_io_size = 1;
 -    config->num_queues = VHOST_USER_BLK_MAX_QUEUES;
 +    config->num_queues = num_queues;
      config->max_discard_sectors = 32768;
      config->max_discard_seg = 1;
      config->discard_sector_alignment = config->blk_size >> 9;
 @@ -XXX,XX +XXX,XX @@ static int vu_blk_exp_create(BlockExport *exp, BlockExportOptions *opts,
      BlockExportOptionsVhostUserBlk *vu_opts = &opts->u.vhost_user_blk;
      Error *local_err = NULL;
      uint64_t logical_block_size;
 +    uint16_t num_queues = VHOST_USER_BLK_NUM_QUEUES_DEFAULT;
      vexp->writable = opts->writable;
      vexp->blkcfg.wce = 0;
 @@ -XXX,XX +XXX,XX @@ static int vu_blk_exp_create(BlockExport *exp, BlockExportOptions *opts,
      }
      vexp->blk_size = logical_block_size;
      blk_set_guest_block_size(exp->blk, logical_block_size);
 +
 +    if (vu_opts->has_num_queues) {
 +        num_queues = vu_opts->num_queues;
 +    }
 +    if (num_queues == 0) {
 +        error_setg(errp, "num-queues must be greater than 0");
 +        return -EINVAL;
 +    }
 +
      vu_blk_initialize_config(blk_bs(exp->blk), &vexp->blkcfg,
 -                               logical_block_size);
 +                             logical_block_size, num_queues);
      blk_add_aio_context_notifier(exp->blk, blk_aio_attached, blk_aio_detach,
                                   vexp);
      if (!vhost_user_server_start(&vexp->vu_server, vu_opts->addr, exp->ctx,
 -                                 VHOST_USER_BLK_MAX_QUEUES, &vu_blk_iface,
 -                                 errp)) {
 +                                 num_queues, &vu_blk_iface, errp)) {
          blk_remove_aio_context_notifier(exp->blk, blk_aio_attached,
                                          blk_aio_detach, vexp);
          return -EADDRNOTAVAIL;
 --
 .26.2

-[PULL v2 25/30] tests/qtest: add multi-queue test case to vhost-user-blk-test
+Deleted patch
-Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
-Message-id: 20201001144604.559733-3-stefanha@redhat.com
-Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
----
- tests/qtest/vhost-user-blk-test.c | 81 +++++++++++++++++++++++++++++--
-file changed, 76 insertions(+), 5 deletions(-)
-diff --git a/tests/qtest/vhost-user-blk-test.c b/tests/qtest/vhost-user-blk-test.c
-index XXXXXXX..XXXXXXX 100644
---- a/tests/qtest/vhost-user-blk-test.c
-+++ b/tests/qtest/vhost-user-blk-test.c
-@@ -XXX,XX +XXX,XX @@ static void pci_hotplug(void *obj, void *data, QGuestAllocator *t_alloc)
-     qpci_unplug_acpi_device_test(qts, "drv1", PCI_SLOT_HP);
- }
-+static void multiqueue(void *obj, void *data, QGuestAllocator *t_alloc)
-+{
-+    QVirtioPCIDevice *pdev1 = obj;
-+    QVirtioDevice *dev1 = &pdev1->vdev;
-+    QVirtioPCIDevice *pdev8;
-+    QVirtioDevice *dev8;
-+    QTestState *qts = pdev1->pdev->bus->qts;
-+    uint64_t features;
-+    uint16_t num_queues;
-+
-+    /*
-+     * The primary device has 1 queue and VIRTIO_BLK_F_MQ is not enabled. The
-+     * VIRTIO specification allows VIRTIO_BLK_F_MQ to be enabled when there is
-+     * only 1 virtqueue, but --device vhost-user-blk-pci doesn't do this (which
-+     * is also spec-compliant).
-+     */
-+    features = qvirtio_get_features(dev1);
-+    g_assert_cmpint(features & (1u << VIRTIO_BLK_F_MQ), ==, 0);
-+    features = features & ~(QVIRTIO_F_BAD_FEATURE |
-+                            (1u << VIRTIO_RING_F_INDIRECT_DESC) |
-+                            (1u << VIRTIO_F_NOTIFY_ON_EMPTY) |
-+                            (1u << VIRTIO_BLK_F_SCSI));
-+    qvirtio_set_features(dev1, features);
-+
-+    /* Hotplug a secondary device with 8 queues */
-+    qtest_qmp_device_add(qts, "vhost-user-blk-pci", "drv1",
-+                         "{'addr': %s, 'chardev': 'char2', 'num-queues': 8}",
-+                         stringify(PCI_SLOT_HP) ".0");
-+
-+    pdev8 = virtio_pci_new(pdev1->pdev->bus,
-+                           &(QPCIAddress) {
-+                               .devfn = QPCI_DEVFN(PCI_SLOT_HP, 0)
-+                           });
-+    g_assert_nonnull(pdev8);
-+    g_assert_cmpint(pdev8->vdev.device_type, ==, VIRTIO_ID_BLOCK);
-+
-+    qos_object_start_hw(&pdev8->obj);
-+
-+    dev8 = &pdev8->vdev;
-+    features = qvirtio_get_features(dev8);
-+    g_assert_cmpint(features & (1u << VIRTIO_BLK_F_MQ),
-+                    ==,
-+                    (1u << VIRTIO_BLK_F_MQ));
-+    features = features & ~(QVIRTIO_F_BAD_FEATURE |
-+                            (1u << VIRTIO_RING_F_INDIRECT_DESC) |
-+                            (1u << VIRTIO_F_NOTIFY_ON_EMPTY) |
-+                            (1u << VIRTIO_BLK_F_SCSI) |
-+                            (1u << VIRTIO_BLK_F_MQ));
-+    qvirtio_set_features(dev8, features);
-+
-+    num_queues = qvirtio_config_readw(dev8,
-+            offsetof(struct virtio_blk_config, num_queues));
-+    g_assert_cmpint(num_queues, ==, 8);
-+
-+    qvirtio_pci_device_disable(pdev8);
-+    qos_object_destroy(&pdev8->obj);
-+
-+    /* unplug secondary disk */
-+    qpci_unplug_acpi_device_test(qts, "drv1", PCI_SLOT_HP);
-+}
-+
- /*
-  * Check that setting the vring addr on a non-existent virtqueue does
-  * not crash.
-@@ -XXX,XX +XXX,XX @@ static void quit_storage_daemon(void *qmp_test_state)
-     g_free(qmp_test_state);
- }
--static char *start_vhost_user_blk(GString *cmd_line, int vus_instances)
-+static char *start_vhost_user_blk(GString *cmd_line, int vus_instances,
-+                                  int num_queues)
- {
-     const char *vhost_user_blk_bin = qtest_qemu_storage_daemon_binary();
-     int fd, qmp_fd, i;
-@@ -XXX,XX +XXX,XX @@ static char *start_vhost_user_blk(GString *cmd_line, int vus_instances)
-         g_string_append_printf(storage_daemon_command,
-             "--blockdev driver=file,node-name=disk%d,filename=%s "
-             "--export type=vhost-user-blk,id=disk%d,addr.type=unix,addr.path=%s,"
--            "node-name=disk%i,writable=on ",
--            i, img_path, i, sock_path, i);
-+            "node-name=disk%i,writable=on,num-queues=%d ",
-+            i, img_path, i, sock_path, i, num_queues);
-         g_string_append_printf(cmd_line, "-chardev socket,id=char%d,path=%s ",
-                                i + 1, sock_path);
-@@ -XXX,XX +XXX,XX @@ static char *start_vhost_user_blk(GString *cmd_line, int vus_instances)
- static void *vhost_user_blk_test_setup(GString *cmd_line, void *arg)
- {
--    start_vhost_user_blk(cmd_line, 1);
-+    start_vhost_user_blk(cmd_line, 1, 1);
-     return arg;
- }
-@@ -XXX,XX +XXX,XX @@ static void *vhost_user_blk_test_setup(GString *cmd_line, void *arg)
- static void *vhost_user_blk_hotplug_test_setup(GString *cmd_line, void *arg)
- {
-     /* "-chardev socket,id=char2" is used for pci_hotplug*/
--    start_vhost_user_blk(cmd_line, 2);
-+    start_vhost_user_blk(cmd_line, 2, 1);
-+    return arg;
-+}
-+
-+static void *vhost_user_blk_multiqueue_test_setup(GString *cmd_line, void *arg)
-+{
-+    start_vhost_user_blk(cmd_line, 2, 8);
-     return arg;
- }
-@@ -XXX,XX +XXX,XX @@ static void register_vhost_user_blk_test(void)
-     opts.before = vhost_user_blk_hotplug_test_setup;
-     qos_add_test("hotplug", "vhost-user-blk-pci", pci_hotplug, &opts);
-+
-+    opts.before = vhost_user_blk_multiqueue_test_setup;
-+    qos_add_test("multiqueue", "vhost-user-blk-pci", multiqueue, &opts);
- }
- libqos_init(register_vhost_user_blk_test);
---
-.26.2

-[PULL v2 26/30] block/io: fix bdrv_co_block_status_above
+[PULL v2 24/28] block/io: fix bdrv_co_block_status_above
 From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
 bdrv_co_block_status_above has several design problems with handling
 short backing files:
 . With want_zeros=true, it may return ret with BDRV_BLOCK_ZERO but
 without BDRV_BLOCK_ALLOCATED flag, when actually short backing file
 which produces these after-EOF zeros is inside requested backing
 sequence.
 . With want_zero=false, it may return pnum=0 prior to actual EOF,
 because of EOF of short backing file.
 Fix these things, making logic about short backing files clearer.
 With fixed bdrv_block_status_above we also have to improve is_zero in
 qcow2 code, otherwise iotest 154 will fail, because with this patch we
 stop to merge zeros of different types (produced by fully unallocated
 in the whole backing chain regions vs produced by short backing files).
 Note also, that this patch leaves for another day the general problem
 around block-status: misuse of BDRV_BLOCK_ALLOCATED as is-fs-allocated
 vs go-to-backing.
 Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
 Reviewed-by: Alberto Garcia <berto@igalia.com>
 Reviewed-by: Eric Blake <eblake@redhat.com>
 Message-id: 20200924194003.22080-2-vsementsov@virtuozzo.com
 [Fix s/comes/come/ as suggested by Eric Blake
 --Stefan]
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  block/io.c    | 68 ++++++++++++++++++++++++++++++++++++++++-----------
  block/qcow2.c | 16 ++++++++++--
 files changed, 68 insertions(+), 16 deletions(-)
 diff --git a/block/io.c b/block/io.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/io.c
 +++ b/block/io.c
 @@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
                                    int64_t *map,
                                    BlockDriverState **file)
  {
 +    int ret;
      BlockDriverState *p;
 -    int ret = 0;
 -    bool first = true;
 +    int64_t eof = 0;
      assert(bs != base);
 -    for (p = bs; p != base; p = bdrv_filter_or_cow_bs(p)) {
 +
 +    ret = bdrv_co_block_status(bs, want_zero, offset, bytes, pnum, map, file);
 +    if (ret < 0 || *pnum == 0 || ret & BDRV_BLOCK_ALLOCATED) {
 +        return ret;
 +    }
 +
 +    if (ret & BDRV_BLOCK_EOF) {
 +        eof = offset + *pnum;
 +    }
 +
 +    assert(*pnum <= bytes);
 +    bytes = *pnum;
 +
 +    for (p = bdrv_filter_or_cow_bs(bs); p != base;
 +         p = bdrv_filter_or_cow_bs(p))
 +    {
          ret = bdrv_co_block_status(p, want_zero, offset, bytes, pnum, map,
                                     file);
          if (ret < 0) {
 -            break;
 +            return ret;
          }
 -        if (ret & BDRV_BLOCK_ZERO && ret & BDRV_BLOCK_EOF && !first) {
 +        if (*pnum == 0) {
              /*
 -             * Reading beyond the end of the file continues to read
 -             * zeroes, but we can only widen the result to the
 -             * unallocated length we learned from an earlier
 -             * iteration.
 +             * The top layer deferred to this layer, and because this layer is
 +             * short, any zeroes that we synthesize beyond EOF behave as if they
 +             * were allocated at this layer.
 +             *
 +             * We don't include BDRV_BLOCK_EOF into ret, as upper layer may be
 +             * larger. We'll add BDRV_BLOCK_EOF if needed at function end, see
 +             * below.
               */
 +            assert(ret & BDRV_BLOCK_EOF);
              *pnum = bytes;
 +            if (file) {
 +                *file = p;
 +            }
 +            ret = BDRV_BLOCK_ZERO | BDRV_BLOCK_ALLOCATED;
 +            break;
          }
 -        if (ret & (BDRV_BLOCK_ZERO | BDRV_BLOCK_DATA)) {
 +        if (ret & BDRV_BLOCK_ALLOCATED) {
 +            /*
 +             * We've found the node and the status, we must break.
 +             *
 +             * Drop BDRV_BLOCK_EOF, as it's not for upper layer, which may be
 +             * larger. We'll add BDRV_BLOCK_EOF if needed at function end, see
 +             * below.
 +             */
 +            ret &= ~BDRV_BLOCK_EOF;
              break;
          }
 -        /* [offset, pnum] unallocated on this layer, which could be only
 -         * the first part of [offset, bytes].  */
 -        bytes = MIN(bytes, *pnum);
 -        first = false;
 +
 +        /*
 +         * OK, [offset, offset + *pnum) region is unallocated on this layer,
 +         * let's continue the diving.
 +         */
 +        assert(*pnum <= bytes);
 +        bytes = *pnum;
 +    }
 +
 +    if (offset + *pnum == eof) {
 +        ret |= BDRV_BLOCK_EOF;
      }
 +
      return ret;
  }
 diff --git a/block/qcow2.c b/block/qcow2.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/qcow2.c
 +++ b/block/qcow2.c
 @@ -XXX,XX +XXX,XX @@ static bool is_zero(BlockDriverState *bs, int64_t offset, int64_t bytes)
      if (!bytes) {
          return true;
      }
 -    res = bdrv_block_status_above(bs, NULL, offset, bytes, &nr, NULL, NULL);
 -    return res >= 0 && (res & BDRV_BLOCK_ZERO) && nr == bytes;
 +
 +    /*
 +     * bdrv_block_status_above doesn't merge different types of zeros, for
 +     * example, zeros which come from the region which is unallocated in
 +     * the whole backing chain, and zeros which come because of a short
 +     * backing file. So, we need a loop.
 +     */
 +    do {
 +        res = bdrv_block_status_above(bs, NULL, offset, bytes, &nr, NULL, NULL);
 +        offset += nr;
 +        bytes -= nr;
 +    } while (res >= 0 && (res & BDRV_BLOCK_ZERO) && nr && bytes);
 +
 +    return res >= 0 && (res & BDRV_BLOCK_ZERO) && bytes == 0;
  }
  static coroutine_fn int qcow2_co_pwrite_zeroes(BlockDriverState *bs,
 --
 .26.2

-[PULL v2 27/30] block/io: bdrv_common_block_status_above: support include_base
+[PULL v2 25/28] block/io: bdrv_common_block_status_above: support include_base
 From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
 In order to reuse bdrv_common_block_status_above in
 bdrv_is_allocated_above, let's support include_base parameter.
 Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
 Reviewed-by: Alberto Garcia <berto@igalia.com>
 Reviewed-by: Eric Blake <eblake@redhat.com>
 Message-id: 20200924194003.22080-3-vsementsov@virtuozzo.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  block/coroutines.h |  2 ++
  block/io.c         | 21 ++++++++++++++-------
 files changed, 16 insertions(+), 7 deletions(-)
 diff --git a/block/coroutines.h b/block/coroutines.h
 index XXXXXXX..XXXXXXX 100644
 --- a/block/coroutines.h
 +++ b/block/coroutines.h
 @@ -XXX,XX +XXX,XX @@ bdrv_pwritev(BdrvChild *child, int64_t offset, unsigned int bytes,
  int coroutine_fn
  bdrv_co_common_block_status_above(BlockDriverState *bs,
                                    BlockDriverState *base,
 +                                  bool include_base,
                                    bool want_zero,
                                    int64_t offset,
                                    int64_t bytes,
 @@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
  int generated_co_wrapper
  bdrv_common_block_status_above(BlockDriverState *bs,
                                 BlockDriverState *base,
 +                               bool include_base,
                                 bool want_zero,
                                 int64_t offset,
                                 int64_t bytes,
 diff --git a/block/io.c b/block/io.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/io.c
 +++ b/block/io.c
 @@ -XXX,XX +XXX,XX @@ early_out:
  int coroutine_fn
  bdrv_co_common_block_status_above(BlockDriverState *bs,
                                    BlockDriverState *base,
 +                                  bool include_base,
                                    bool want_zero,
                                    int64_t offset,
                                    int64_t bytes,
 @@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
      BlockDriverState *p;
      int64_t eof = 0;
 -    assert(bs != base);
 +    assert(include_base || bs != base);
 +    assert(!include_base || base); /* Can't include NULL base */
      ret = bdrv_co_block_status(bs, want_zero, offset, bytes, pnum, map, file);
 -    if (ret < 0 || *pnum == 0 || ret & BDRV_BLOCK_ALLOCATED) {
 +    if (ret < 0 || *pnum == 0 || ret & BDRV_BLOCK_ALLOCATED || bs == base) {
          return ret;
      }
 @@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
      assert(*pnum <= bytes);
      bytes = *pnum;
 -    for (p = bdrv_filter_or_cow_bs(bs); p != base;
 +    for (p = bdrv_filter_or_cow_bs(bs); include_base || p != base;
           p = bdrv_filter_or_cow_bs(p))
      {
          ret = bdrv_co_block_status(p, want_zero, offset, bytes, pnum, map,
 @@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
              break;
          }
 +        if (p == base) {
 +            assert(include_base);
 +            break;
 +        }
 +
          /*
           * OK, [offset, offset + *pnum) region is unallocated on this layer,
           * let's continue the diving.
 @@ -XXX,XX +XXX,XX @@ int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base,
                              int64_t offset, int64_t bytes, int64_t *pnum,
                              int64_t *map, BlockDriverState **file)
  {
 -    return bdrv_common_block_status_above(bs, base, true, offset, bytes,
 +    return bdrv_common_block_status_above(bs, base, false, true, offset, bytes,
                                            pnum, map, file);
  }
 @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset,
      int ret;
      int64_t dummy;
 -    ret = bdrv_common_block_status_above(bs, bdrv_filter_or_cow_bs(bs), false,
 -                                         offset, bytes, pnum ? pnum : &dummy,
 -                                         NULL, NULL);
 +    ret = bdrv_common_block_status_above(bs, bs, true, false, offset,
 +                                         bytes, pnum ? pnum : &dummy, NULL,
 +                                         NULL);
      if (ret < 0) {
          return ret;
      }
 --
 .26.2

-[PULL v2 28/30] block/io: bdrv_common_block_status_above: support bs == base
+[PULL v2 26/28] block/io: bdrv_common_block_status_above: support bs == base
 From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
 We are going to reuse bdrv_common_block_status_above in
 bdrv_is_allocated_above. bdrv_is_allocated_above may be called with
 include_base == false and still bs == base (for ex. from img_rebase()).
 So, support this corner case.
 Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
 Reviewed-by: Kevin Wolf <kwolf@redhat.com>
 Reviewed-by: Eric Blake <eblake@redhat.com>
 Reviewed-by: Alberto Garcia <berto@igalia.com>
 Message-id: 20200924194003.22080-4-vsementsov@virtuozzo.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  block/io.c | 6 +++++-
 file changed, 5 insertions(+), 1 deletion(-)
 diff --git a/block/io.c b/block/io.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/io.c
 +++ b/block/io.c
 @@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
      BlockDriverState *p;
      int64_t eof = 0;
 -    assert(include_base || bs != base);
      assert(!include_base || base); /* Can't include NULL base */
 +    if (!include_base && bs == base) {
 +        *pnum = bytes;
 +        return 0;
 +    }
 +
      ret = bdrv_co_block_status(bs, want_zero, offset, bytes, pnum, map, file);
      if (ret < 0 || *pnum == 0 || ret & BDRV_BLOCK_ALLOCATED || bs == base) {
          return ret;
 --
 .26.2

-[PULL v2 29/30] block/io: fix bdrv_is_allocated_above
+[PULL v2 27/28] block/io: fix bdrv_is_allocated_above
 From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
 bdrv_is_allocated_above wrongly handles short backing files: it reports
 after-EOF space as UNALLOCATED which is wrong, as on read the data is
 generated on the level of short backing file (if all overlays have
 unallocated areas at that place).
 Reusing bdrv_common_block_status_above fixes the issue and unifies code
 path.
 Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
 Reviewed-by: Eric Blake <eblake@redhat.com>
 Reviewed-by: Alberto Garcia <berto@igalia.com>
 Message-id: 20200924194003.22080-5-vsementsov@virtuozzo.com
 [Fix s/has/have/ as suggested by Eric Blake. Fix s/area/areas/.
 --Stefan]
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  block/io.c | 43 +++++--------------------------------------
 file changed, 5 insertions(+), 38 deletions(-)
 diff --git a/block/io.c b/block/io.c
 index XXXXXXX..XXXXXXX 100644
 --- a/block/io.c
 +++ b/block/io.c
 @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset,
   * at 'offset + *pnum' may return the same allocation status (in other
   * words, the result is not necessarily the maximum possible range);
   * but 'pnum' will only be 0 when end of file is reached.
 - *
   */
  int bdrv_is_allocated_above(BlockDriverState *top,
                              BlockDriverState *base,
                              bool include_base, int64_t offset,
                              int64_t bytes, int64_t *pnum)
  {
 -    BlockDriverState *intermediate;
 -    int ret;
 -    int64_t n = bytes;
 -
 -    assert(base || !include_base);
 -
 -    intermediate = top;
 -    while (include_base || intermediate != base) {
 -        int64_t pnum_inter;
 -        int64_t size_inter;
 -
 -        assert(intermediate);
 -        ret = bdrv_is_allocated(intermediate, offset, bytes, &pnum_inter);
 -        if (ret < 0) {
 -            return ret;
 -        }
 -        if (ret) {
 -            *pnum = pnum_inter;
 -            return 1;
 -        }
 -
 -        size_inter = bdrv_getlength(intermediate);
 -        if (size_inter < 0) {
 -            return size_inter;
 -        }
 -        if (n > pnum_inter &&
 -            (intermediate == top || offset + pnum_inter < size_inter)) {
 -            n = pnum_inter;
 -        }
 -
 -        if (intermediate == base) {
 -            break;
 -        }
 -
 -        intermediate = bdrv_filter_or_cow_bs(intermediate);
 +    int ret = bdrv_common_block_status_above(top, base, include_base, false,
 +                                             offset, bytes, pnum, NULL, NULL);
 +    if (ret < 0) {
 +        return ret;
      }
 -    *pnum = n;
 -    return 0;
 +    return !!(ret & BDRV_BLOCK_ALLOCATED);
  }
  int coroutine_fn
 --
 .26.2

-[PULL v2 30/30] iotests: add commit top->base cases to 274
+[PULL v2 28/28] iotests: add commit top->base cases to 274
 From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
 These cases are fixed by previous patches around block_status and
 is_allocated.
 Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
 Reviewed-by: Eric Blake <eblake@redhat.com>
 Reviewed-by: Alberto Garcia <berto@igalia.com>
 Message-id: 20200924194003.22080-6-vsementsov@virtuozzo.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  tests/qemu-iotests/274     | 20 +++++++++++
  tests/qemu-iotests/274.out | 68 ++++++++++++++++++++++++++++++++++++++
 files changed, 88 insertions(+)
 diff --git a/tests/qemu-iotests/274 b/tests/qemu-iotests/274
 index XXXXXXX..XXXXXXX 100755
 --- a/tests/qemu-iotests/274
 +++ b/tests/qemu-iotests/274
 @@ -XXX,XX +XXX,XX @@ with iotests.FilePath('base') as base, \
      iotests.qemu_io_log('-c', 'read -P 1 0 %d' % size_short, mid)
      iotests.qemu_io_log('-c', 'read -P 0 %d %d' % (size_short, size_diff), mid)
 +    iotests.log('=== Testing qemu-img commit (top -> base) ===')
 +
 +    create_chain()
 +    iotests.qemu_img_log('commit', '-b', base, top)
 +    iotests.img_info_log(base)
 +    iotests.qemu_io_log('-c', 'read -P 1 0 %d' % size_short, base)
 +    iotests.qemu_io_log('-c', 'read -P 0 %d %d' % (size_short, size_diff), base)
 +
 +    iotests.log('=== Testing QMP active commit (top -> base) ===')
 +
 +    create_chain()
 +    with create_vm() as vm:
 +        vm.launch()
 +        vm.qmp_log('block-commit', device='top', base_node='base',
 +                   job_id='job0', auto_dismiss=False)
 +        vm.run_job('job0', wait=5)
 +
 +    iotests.img_info_log(mid)
 +    iotests.qemu_io_log('-c', 'read -P 1 0 %d' % size_short, base)
 +    iotests.qemu_io_log('-c', 'read -P 0 %d %d' % (size_short, size_diff), base)
      iotests.log('== Resize tests ==')
 diff --git a/tests/qemu-iotests/274.out b/tests/qemu-iotests/274.out
 index XXXXXXX..XXXXXXX 100644
 --- a/tests/qemu-iotests/274.out
 +++ b/tests/qemu-iotests/274.out
 @@ -XXX,XX +XXX,XX @@ read 1048576/1048576 bytes at offset 0
  read 1048576/1048576 bytes at offset 1048576
 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 +=== Testing qemu-img commit (top -> base) ===
 +Formatting 'TEST_DIR/PID-base', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=2097152 lazy_refcounts=off refcount_bits=16
 +
 +Formatting 'TEST_DIR/PID-mid', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=1048576 backing_file=TEST_DIR/PID-base backing_fmt=qcow2 lazy_refcounts=off refcount_bits=16
 +
 +Formatting 'TEST_DIR/PID-top', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=2097152 backing_file=TEST_DIR/PID-mid backing_fmt=qcow2 lazy_refcounts=off refcount_bits=16
 +
 +wrote 2097152/2097152 bytes at offset 0
 +2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 +
 +Image committed.
 +
 +image: TEST_IMG
 +file format: IMGFMT
 +virtual size: 2 MiB (2097152 bytes)
 +cluster_size: 65536
 +Format specific information:
 +    compat: 1.1
 +    compression type: zlib
 +    lazy refcounts: false
 +    refcount bits: 16
 +    corrupt: false
 +    extended l2: false
 +
 +read 1048576/1048576 bytes at offset 0
 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 +
 +read 1048576/1048576 bytes at offset 1048576
 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 +
 +=== Testing QMP active commit (top -> base) ===
 +Formatting 'TEST_DIR/PID-base', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=2097152 lazy_refcounts=off refcount_bits=16
 +
 +Formatting 'TEST_DIR/PID-mid', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=1048576 backing_file=TEST_DIR/PID-base backing_fmt=qcow2 lazy_refcounts=off refcount_bits=16
 +
 +Formatting 'TEST_DIR/PID-top', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=2097152 backing_file=TEST_DIR/PID-mid backing_fmt=qcow2 lazy_refcounts=off refcount_bits=16
 +
 +wrote 2097152/2097152 bytes at offset 0
 +2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 +
 +{"execute": "block-commit", "arguments": {"auto-dismiss": false, "base-node": "base", "device": "top", "job-id": "job0"}}
 +{"return": {}}
 +{"execute": "job-complete", "arguments": {"id": "job0"}}
 +{"return": {}}
 +{"data": {"device": "job0", "len": 1048576, "offset": 1048576, "speed": 0, "type": "commit"}, "event": "BLOCK_JOB_READY", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 +{"data": {"device": "job0", "len": 1048576, "offset": 1048576, "speed": 0, "type": "commit"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 +{"execute": "job-dismiss", "arguments": {"id": "job0"}}
 +{"return": {}}
 +image: TEST_IMG
 +file format: IMGFMT
 +virtual size: 1 MiB (1048576 bytes)
 +cluster_size: 65536
 +backing file: TEST_DIR/PID-base
 +backing file format: IMGFMT
 +Format specific information:
 +    compat: 1.1
 +    compression type: zlib
 +    lazy refcounts: false
 +    refcount bits: 16
 +    corrupt: false
 +    extended l2: false
 +
 +read 1048576/1048576 bytes at offset 0
 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 +
 +read 1048576/1048576 bytes at offset 1048576
 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 +
  == Resize tests ==
  === preallocation=off ===
  Formatting 'TEST_DIR/PID-base', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=6442450944 lazy_refcounts=off refcount_bits=16
 --
 .26.2

The following changes since commit 2387df497b4b4bcf754eb7398edca82889e2ef54:

Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2020-10-10' into staging (2020-10-12 11:29:42 +0100)

are available in the Git repository at:

https://gitlab.com/stefanha/qemu.git tags/block-pull-request

for you to fetch changes up to 3664ec6bbe236126b79d251d4037889e7181ab55:

iotests: add commit top->base cases to 274 (2020-10-12 16:47:58 +0100)

----------------------------------------------------------------
Pull request

v2:
 * Rebase and resolve conflict with commit 029a88c9a7e3 ("qemu-nbd: Honor
   SIGINT and SIGHUP") [Peter]

----------------------------------------------------------------

Coiby Xu (7):
  libvhost-user: Allow vu_message_read to be replaced
  libvhost-user: remove watch for kick_fd when de-initialize vu-dev
  util/vhost-user-server: generic vhost user server
  block: move logical block size check function to a common utility
    function
  block/export: vhost-user block device backend server
  test: new qTest case to test the vhost-user-blk-server
  MAINTAINERS: Add vhost-user block device backend server maintainer

Philippe Mathieu-Daudé (1):
  block/nvme: Add driver statistics for access alignment and hw errors

Stefan Hajnoczi (17):
  util/vhost-user-server: s/fileds/fields/ typo fix
  util/vhost-user-server: drop unnecessary QOM cast
  util/vhost-user-server: drop unnecessary watch deletion
  block/export: consolidate request structs into VuBlockReq
  util/vhost-user-server: drop unused DevicePanicNotifier
  util/vhost-user-server: fix memory leak in vu_message_read()
  util/vhost-user-server: check EOF when reading payload
  util/vhost-user-server: rework vu_client_trip() coroutine lifecycle
  block/export: report flush errors
  block/export: convert vhost-user-blk server to block export API
  util/vhost-user-server: move header to include/
  util/vhost-user-server: use static library in meson.build
  qemu-storage-daemon: avoid compiling blockdev_ss twice
  block: move block exports to libblockdev
  block/export: add iothread and fixed-iothread options
  block/export: add vhost-user-blk multi-queue support
  tests/qtest: add multi-queue test case to vhost-user-blk-test

Vladimir Sementsov-Ogievskiy (5):
  block/io: fix bdrv_co_block_status_above
  block/io: bdrv_common_block_status_above: support include_base
  block/io: bdrv_common_block_status_above: support bs == base
  block/io: fix bdrv_is_allocated_above
  iotests: add commit top->base cases to 274

MAINTAINERS                                |  10 +
 qapi/block-core.json                       |  24 +-
 qapi/block-export.json                     |  36 +-
 block/coroutines.h                         |   2 +
 block/export/vhost-user-blk-server.h       |  19 +
 contrib/libvhost-user/libvhost-user.h      |  21 +
 include/qemu/vhost-user-server.h           |  65 ++
 tests/qtest/libqos/libqtest.h              |  17 +
 tests/qtest/libqos/vhost-user-blk.h        |  48 ++
 util/block-helpers.h                       |  19 +
 block/export/export.c                      |  37 +-
 block/export/vhost-user-blk-server.c       | 431 +++++++++++
 block/io.c                                 | 132 ++--
 block/nvme.c                               |  27 +
 block/qcow2.c                              |  16 +-
 contrib/libvhost-user/libvhost-user-glib.c |   2 +-
 contrib/libvhost-user/libvhost-user.c      |  15 +-
 hw/core/qdev-properties-system.c           |  31 +-
 nbd/server.c                               |   2 -
 qemu-nbd.c                                 |  25 +-
 softmmu/vl.c                               |   4 +
 stubs/blk-exp-close-all.c                  |   7 +
 tests/qtest/libqos/vhost-user-blk.c        | 129 ++++
 tests/qtest/libqtest.c                     |  36 +-
 tests/qtest/vhost-user-blk-test.c          | 822 +++++++++++++++++++++
 tests/vhost-user-bridge.c                  |   2 +
 tools/virtiofsd/fuse_virtio.c              |   4 +-
 util/block-helpers.c                       |  46 ++
 util/vhost-user-server.c                   | 446 +++++++++++
 block/export/meson.build                   |   3 +-
 contrib/libvhost-user/meson.build          |   1 +
 meson.build                                |  22 +-
 nbd/meson.build                            |   2 +
 storage-daemon/meson.build                 |   3 +-
 stubs/meson.build                          |   1 +
 tests/qemu-iotests/274                     |  20 +
 tests/qemu-iotests/274.out                 |  68 ++
 tests/qtest/libqos/meson.build             |   1 +
 tests/qtest/meson.build                    |   4 +-
 util/meson.build                           |   4 +
 40 files changed, 2476 insertions(+), 128 deletions(-)
 create mode 100644 block/export/vhost-user-blk-server.h
 create mode 100644 include/qemu/vhost-user-server.h
 create mode 100644 tests/qtest/libqos/vhost-user-blk.h
 create mode 100644 util/block-helpers.h
 create mode 100644 block/export/vhost-user-blk-server.c
 create mode 100644 stubs/blk-exp-close-all.c
 create mode 100644 tests/qtest/libqos/vhost-user-blk.c
 create mode 100644 tests/qtest/vhost-user-blk-test.c
 create mode 100644 util/block-helpers.c
 create mode 100644 util/vhost-user-server.c

-- 
2.26.2

From: Philippe Mathieu-Daudé <philmd@redhat.com>

Keep statistics of some hardware errors, and number of
aligned/unaligned I/O accesses.

QMP example booting a full RHEL 8.3 aarch64 guest:

{ "execute": "query-blockstats" }
{
    "return": [
        {
            "device": "",
            "node-name": "drive0",
            "stats": {
                "flush_total_time_ns": 6026948,
                "wr_highest_offset": 3383991230464,
                "wr_total_time_ns": 807450995,
                "failed_wr_operations": 0,
                "failed_rd_operations": 0,
                "wr_merged": 3,
                "wr_bytes": 50133504,
                "failed_unmap_operations": 0,
                "failed_flush_operations": 0,
                "account_invalid": false,
                "rd_total_time_ns": 1846979900,
                "flush_operations": 130,
                "wr_operations": 659,
                "rd_merged": 1192,
                "rd_bytes": 218244096,
                "account_failed": false,
                "idle_time_ns": 2678641497,
                "rd_operations": 7406,
            },
            "driver-specific": {
                "driver": "nvme",
                "completion-errors": 0,
                "unaligned-accesses": 2959,
                "aligned-accesses": 4477
            },
            "qdev": "/machine/peripheral-anon/device[0]/virtio-backend"
        }
    ]
}

Suggested-by: Stefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20201001162939.1567915-1-philmd@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 qapi/block-core.json | 24 +++++++++++++++++++++++-
 block/nvme.c         | 27 +++++++++++++++++++++++++++
 2 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/qapi/block-core.json b/qapi/block-core.json
index XXXXXXX..XXXXXXX 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -XXX,XX +XXX,XX @@
       'discard-nb-failed': 'uint64',
       'discard-bytes-ok': 'uint64' } }
 
+##
+# @BlockStatsSpecificNvme:
+#
+# NVMe driver statistics
+#
+# @completion-errors: The number of completion errors.
+#
+# @aligned-accesses: The number of aligned accesses performed by
+#                    the driver.
+#
+# @unaligned-accesses: The number of unaligned accesses performed by
+#                      the driver.
+#
+# Since: 5.2
+##
+{ 'struct': 'BlockStatsSpecificNvme',
+  'data': {
+      'completion-errors': 'uint64',
+      'aligned-accesses': 'uint64',
+      'unaligned-accesses': 'uint64' } }
+
 ##
 # @BlockStatsSpecific:
 #
@@ -XXX,XX +XXX,XX @@
   'discriminator': 'driver',
   'data': {
       'file': 'BlockStatsSpecificFile',
-      'host_device': 'BlockStatsSpecificFile' } }
+      'host_device': 'BlockStatsSpecificFile',
+      'nvme': 'BlockStatsSpecificNvme' } }
 
 ##
 # @BlockStats:
diff --git a/block/nvme.c b/block/nvme.c
index XXXXXXX..XXXXXXX 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -XXX,XX +XXX,XX @@ struct BDRVNVMeState {
 
     /* PCI address (required for nvme_refresh_filename()) */
     char *device;
+
+    struct {
+        uint64_t completion_errors;
+        uint64_t aligned_accesses;
+        uint64_t unaligned_accesses;
+    } stats;
 };
 
 #define NVME_BLOCK_OPT_DEVICE "device"
@@ -XXX,XX +XXX,XX @@ static bool nvme_process_completion(NVMeQueuePair *q)
             break;
         }
         ret = nvme_translate_error(c);
+        if (ret) {
+            s->stats.completion_errors++;
+        }
         q->cq.head = (q->cq.head + 1) % NVME_QUEUE_SIZE;
         if (!q->cq.head) {
             q->cq_phase = !q->cq_phase;
@@ -XXX,XX +XXX,XX @@ static int nvme_co_prw(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
     assert(QEMU_IS_ALIGNED(bytes, s->page_size));
     assert(bytes <= s->max_transfer);
     if (nvme_qiov_aligned(bs, qiov)) {
+        s->stats.aligned_accesses++;
         return nvme_co_prw_aligned(bs, offset, bytes, qiov, is_write, flags);
     }
+    s->stats.unaligned_accesses++;
     trace_nvme_prw_buffered(s, offset, bytes, qiov->niov, is_write);
     buf = qemu_try_memalign(s->page_size, bytes);
 
@@ -XXX,XX +XXX,XX @@ static void nvme_unregister_buf(BlockDriverState *bs, void *host)
     qemu_vfio_dma_unmap(s->vfio, host);
 }
 
+static BlockStatsSpecific *nvme_get_specific_stats(BlockDriverState *bs)
+{
+    BlockStatsSpecific *stats = g_new(BlockStatsSpecific, 1);
+    BDRVNVMeState *s = bs->opaque;
+
+    stats->driver = BLOCKDEV_DRIVER_NVME;
+    stats->u.nvme = (BlockStatsSpecificNvme) {
+        .completion_errors = s->stats.completion_errors,
+        .aligned_accesses = s->stats.aligned_accesses,
+        .unaligned_accesses = s->stats.unaligned_accesses,
+    };
+
+    return stats;
+}
+
 static const char *const nvme_strong_runtime_opts[] = {
     NVME_BLOCK_OPT_DEVICE,
     NVME_BLOCK_OPT_NAMESPACE,
@@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_nvme = {
     .bdrv_refresh_filename    = nvme_refresh_filename,
     .bdrv_refresh_limits      = nvme_refresh_limits,
     .strong_runtime_opts      = nvme_strong_runtime_opts,
+    .bdrv_get_specific_stats  = nvme_get_specific_stats,
 
     .bdrv_detach_aio_context  = nvme_detach_aio_context,
     .bdrv_attach_aio_context  = nvme_attach_aio_context,
-- 
2.26.2

From: Coiby Xu <coiby.xu@gmail.com>

Allow vu_message_read to be replaced by one which will make use of the
QIOChannel functions. Thus reading vhost-user message won't stall the
guest. For slave channel, we still use the default vu_message_read.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200918080912.321299-2-coiby.xu@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 contrib/libvhost-user/libvhost-user.h      | 21 +++++++++++++++++++++
 contrib/libvhost-user/libvhost-user-glib.c |  2 +-
 contrib/libvhost-user/libvhost-user.c      | 14 +++++++-------
 tests/vhost-user-bridge.c                  |  2 ++
 tools/virtiofsd/fuse_virtio.c              |  4 ++--
 5 files changed, 33 insertions(+), 10 deletions(-)

diff --git a/contrib/libvhost-user/libvhost-user.h b/contrib/libvhost-user/libvhost-user.h
index XXXXXXX..XXXXXXX 100644
--- a/contrib/libvhost-user/libvhost-user.h
+++ b/contrib/libvhost-user/libvhost-user.h
@@ -XXX,XX +XXX,XX @@
  */
 #define VHOST_USER_MAX_RAM_SLOTS 32
 
+#define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64)
+
 typedef enum VhostSetConfigType {
     VHOST_SET_CONFIG_TYPE_MASTER = 0,
     VHOST_SET_CONFIG_TYPE_MIGRATION = 1,
@@ -XXX,XX +XXX,XX @@ typedef uint64_t (*vu_get_features_cb) (VuDev *dev);
 typedef void (*vu_set_features_cb) (VuDev *dev, uint64_t features);
 typedef int (*vu_process_msg_cb) (VuDev *dev, VhostUserMsg *vmsg,
                                   int *do_reply);
+typedef bool (*vu_read_msg_cb) (VuDev *dev, int sock, VhostUserMsg *vmsg);
 typedef void (*vu_queue_set_started_cb) (VuDev *dev, int qidx, bool started);
 typedef bool (*vu_queue_is_processed_in_order_cb) (VuDev *dev, int qidx);
 typedef int (*vu_get_config_cb) (VuDev *dev, uint8_t *config, uint32_t len);
@@ -XXX,XX +XXX,XX @@ struct VuDev {
     bool broken;
     uint16_t max_queues;
 
+    /* @read_msg: custom method to read vhost-user message
+     *
+     * Read data from vhost_user socket fd and fill up
+     * the passed VhostUserMsg *vmsg struct.
+     *
+     * If reading fails, it should close the received set of file
+     * descriptors as socket message's auxiliary data.
+     *
+     * For the details, please refer to vu_message_read in libvhost-user.c
+     * which will be used by default if not custom method is provided when
+     * calling vu_init
+     *
+     * Returns: true if vhost-user message successfully received,
+     *          otherwise return false.
+     *
+     */
+    vu_read_msg_cb read_msg;
     /* @set_watch: add or update the given fd to the watch set,
      * call cb when condition is met */
     vu_set_watch_cb set_watch;
@@ -XXX,XX +XXX,XX @@ bool vu_init(VuDev *dev,
              uint16_t max_queues,
              int socket,
              vu_panic_cb panic,
+             vu_read_msg_cb read_msg,
              vu_set_watch_cb set_watch,
              vu_remove_watch_cb remove_watch,
              const VuDevIface *iface);
diff --git a/contrib/libvhost-user/libvhost-user-glib.c b/contrib/libvhost-user/libvhost-user-glib.c
index XXXXXXX..XXXXXXX 100644
--- a/contrib/libvhost-user/libvhost-user-glib.c
+++ b/contrib/libvhost-user/libvhost-user-glib.c
@@ -XXX,XX +XXX,XX @@ vug_init(VugDev *dev, uint16_t max_queues, int socket,
     g_assert(dev);
     g_assert(iface);
 
-    if (!vu_init(&dev->parent, max_queues, socket, panic, set_watch,
+    if (!vu_init(&dev->parent, max_queues, socket, panic, NULL, set_watch,
                  remove_watch, iface)) {
         return false;
     }
diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c
index XXXXXXX..XXXXXXX 100644
--- a/contrib/libvhost-user/libvhost-user.c
+++ b/contrib/libvhost-user/libvhost-user.c
@@ -XXX,XX +XXX,XX @@
 /* The version of inflight buffer */
 #define INFLIGHT_VERSION 1
 
-#define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64)
-
 /* The version of the protocol we support */
 #define VHOST_USER_VERSION 1
 #define LIBVHOST_USER_DEBUG 0
@@ -XXX,XX +XXX,XX @@ have_userfault(void)
 }
 
 static bool
-vu_message_read(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
+vu_message_read_default(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
 {
     char control[CMSG_SPACE(VHOST_MEMORY_BASELINE_NREGIONS * sizeof(int))] = {};
     struct iovec iov = {
@@ -XXX,XX +XXX,XX @@ vu_process_message_reply(VuDev *dev, const VhostUserMsg *vmsg)
         goto out;
     }
 
-    if (!vu_message_read(dev, dev->slave_fd, &msg_reply)) {
+    if (!vu_message_read_default(dev, dev->slave_fd, &msg_reply)) {
         goto out;
     }
 
@@ -XXX,XX +XXX,XX @@ vu_set_mem_table_exec_postcopy(VuDev *dev, VhostUserMsg *vmsg)
     /* Wait for QEMU to confirm that it's registered the handler for the
      * faults.
      */
-    if (!vu_message_read(dev, dev->sock, vmsg) ||
+    if (!dev->read_msg(dev, dev->sock, vmsg) ||
         vmsg->size != sizeof(vmsg->payload.u64) ||
         vmsg->payload.u64 != 0) {
         vu_panic(dev, "failed to receive valid ack for postcopy set-mem-table");
@@ -XXX,XX +XXX,XX @@ vu_dispatch(VuDev *dev)
     int reply_requested;
     bool need_reply, success = false;
 
-    if (!vu_message_read(dev, dev->sock, &vmsg)) {
+    if (!dev->read_msg(dev, dev->sock, &vmsg)) {
         goto end;
     }
 
@@ -XXX,XX +XXX,XX @@ vu_init(VuDev *dev,
         uint16_t max_queues,
         int socket,
         vu_panic_cb panic,
+        vu_read_msg_cb read_msg,
         vu_set_watch_cb set_watch,
         vu_remove_watch_cb remove_watch,
         const VuDevIface *iface)
@@ -XXX,XX +XXX,XX @@ vu_init(VuDev *dev,
 
     dev->sock = socket;
     dev->panic = panic;
+    dev->read_msg = read_msg ? read_msg : vu_message_read_default;
     dev->set_watch = set_watch;
     dev->remove_watch = remove_watch;
     dev->iface = iface;
@@ -XXX,XX +XXX,XX @@ static void _vu_queue_notify(VuDev *dev, VuVirtq *vq, bool sync)
 
         vu_message_write(dev, dev->slave_fd, &vmsg);
         if (ack) {
-            vu_message_read(dev, dev->slave_fd, &vmsg);
+            vu_message_read_default(dev, dev->slave_fd, &vmsg);
         }
         return;
     }
diff --git a/tests/vhost-user-bridge.c b/tests/vhost-user-bridge.c
index XXXXXXX..XXXXXXX 100644
--- a/tests/vhost-user-bridge.c
+++ b/tests/vhost-user-bridge.c
@@ -XXX,XX +XXX,XX @@ vubr_accept_cb(int sock, void *ctx)
                  VHOST_USER_BRIDGE_MAX_QUEUES,
                  conn_fd,
                  vubr_panic,
+                 NULL,
                  vubr_set_watch,
                  vubr_remove_watch,
                  &vuiface)) {
@@ -XXX,XX +XXX,XX @@ vubr_new(const char *path, bool client)
                      VHOST_USER_BRIDGE_MAX_QUEUES,
                      dev->sock,
                      vubr_panic,
+                     NULL,
                      vubr_set_watch,
                      vubr_remove_watch,
                      &vuiface)) {
diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index XXXXXXX..XXXXXXX 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -XXX,XX +XXX,XX @@ int virtio_session_mount(struct fuse_session *se)
     se->vu_socketfd = data_sock;
     se->virtio_dev->se = se;
     pthread_rwlock_init(&se->virtio_dev->vu_dispatch_rwlock, NULL);
-    vu_init(&se->virtio_dev->dev, 2, se->vu_socketfd, fv_panic, fv_set_watch,
-            fv_remove_watch, &fv_iface);
+    vu_init(&se->virtio_dev->dev, 2, se->vu_socketfd, fv_panic, NULL,
+            fv_set_watch, fv_remove_watch, &fv_iface);
 
     return 0;
 }
-- 
2.26.2

From: Coiby Xu <coiby.xu@gmail.com>

Sharing QEMU devices via vhost-user protocol.

Only one vhost-user client can connect to the server one time.

diff --git a/util/vhost-user-server.h b/util/vhost-user-server.h
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/util/vhost-user-server.h
@@ -XXX,XX +XXX,XX @@
+/*
+ * Sharing QEMU devices via vhost-user protocol
+ *
+ * Copyright (c) Coiby Xu <coiby.xu@gmail.com>.
+ * Copyright (c) 2020 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ */
+
+#ifndef VHOST_USER_SERVER_H
+#define VHOST_USER_SERVER_H
+
+#include "contrib/libvhost-user/libvhost-user.h"
+#include "io/channel-socket.h"
+#include "io/channel-file.h"
+#include "io/net-listener.h"
+#include "qemu/error-report.h"
+#include "qapi/error.h"
+#include "standard-headers/linux/virtio_blk.h"
+
+typedef struct VuFdWatch {
+    VuDev *vu_dev;
+    int fd; /*kick fd*/
+    void *pvt;
+    vu_watch_cb cb;
+    bool processing;
+    QTAILQ_ENTRY(VuFdWatch) next;
+} VuFdWatch;
+
+typedef struct VuServer VuServer;
+typedef void DevicePanicNotifierFn(VuServer *server);
+
+struct VuServer {
+    QIONetListener *listener;
+    AioContext *ctx;
+    DevicePanicNotifierFn *device_panic_notifier;
+    int max_queues;
+    const VuDevIface *vu_iface;
+    VuDev vu_dev;
+    QIOChannel *ioc; /* The I/O channel with the client */
+    QIOChannelSocket *sioc; /* The underlying data channel with the client */
+    /* IOChannel for fd provided via VHOST_USER_SET_SLAVE_REQ_FD */
+    QIOChannel *ioc_slave;
+    QIOChannelSocket *sioc_slave;
+    Coroutine *co_trip; /* coroutine for processing VhostUserMsg */
+    QTAILQ_HEAD(, VuFdWatch) vu_fd_watches;
+    /* restart coroutine co_trip if AIOContext is changed */
+    bool aio_context_changed;
+    bool processing_msg;
+};
+
+bool vhost_user_server_start(VuServer *server,
+                             SocketAddress *unix_socket,
+                             AioContext *ctx,
+                             uint16_t max_queues,
+                             DevicePanicNotifierFn *device_panic_notifier,
+                             const VuDevIface *vu_iface,
+                             Error **errp);
+
+void vhost_user_server_stop(VuServer *server);
+
+void vhost_user_server_set_aio_context(VuServer *server, AioContext *ctx);
+
+#endif /* VHOST_USER_SERVER_H */
diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@
+/*
+ * Sharing QEMU devices via vhost-user protocol
+ *
+ * Copyright (c) Coiby Xu <coiby.xu@gmail.com>.
+ * Copyright (c) 2020 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ */
+#include "qemu/osdep.h"
+#include "qemu/main-loop.h"
+#include "vhost-user-server.h"
+
+static void vmsg_close_fds(VhostUserMsg *vmsg)
+{
+    int i;
+    for (i = 0; i < vmsg->fd_num; i++) {
+        close(vmsg->fds[i]);
+    }
+}
+
+static void vmsg_unblock_fds(VhostUserMsg *vmsg)
+{
+    int i;
+    for (i = 0; i < vmsg->fd_num; i++) {
+        qemu_set_nonblock(vmsg->fds[i]);
+    }
+}
+
+static void vu_accept(QIONetListener *listener, QIOChannelSocket *sioc,
+                      gpointer opaque);
+
+static void close_client(VuServer *server)
+{
+    /*
+     * Before closing the client
+     *
+     * 1. Let vu_client_trip stop processing new vhost-user msg
+     *
+     * 2. remove kick_handler
+     *
+     * 3. wait for the kick handler to be finished
+     *
+     * 4. wait for the current vhost-user msg to be finished processing
+     */
+
+    QIOChannelSocket *sioc = server->sioc;
+    /* When this is set vu_client_trip will stop new processing vhost-user message */
+    server->sioc = NULL;
+
+    VuFdWatch *vu_fd_watch, *next;
+    QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
+        aio_set_fd_handler(server->ioc->ctx, vu_fd_watch->fd, true, NULL,
+                           NULL, NULL, NULL);
+    }
+
+    while (!QTAILQ_EMPTY(&server->vu_fd_watches)) {
+        QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
+            if (!vu_fd_watch->processing) {
+                QTAILQ_REMOVE(&server->vu_fd_watches, vu_fd_watch, next);
+                g_free(vu_fd_watch);
+            }
+        }
+    }
+
+    while (server->processing_msg) {
+        if (server->ioc->read_coroutine) {
+            server->ioc->read_coroutine = NULL;
+            qio_channel_set_aio_fd_handler(server->ioc, server->ioc->ctx, NULL,
+                                           NULL, server->ioc);
+            server->processing_msg = false;
+        }
+    }
+
+    vu_deinit(&server->vu_dev);
+    object_unref(OBJECT(sioc));
+    object_unref(OBJECT(server->ioc));
+}
+
+static void panic_cb(VuDev *vu_dev, const char *buf)
+{
+    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+
+    /* avoid while loop in close_client */
+    server->processing_msg = false;
+
+    if (buf) {
+        error_report("vu_panic: %s", buf);
+    }
+
+    if (server->sioc) {
+        close_client(server);
+    }
+
+    if (server->device_panic_notifier) {
+        server->device_panic_notifier(server);
+    }
+
+    /*
+     * Set the callback function for network listener so another
+     * vhost-user client can connect to this server
+     */
+    qio_net_listener_set_client_func(server->listener,
+                                     vu_accept,
+                                     server,
+                                     NULL);
+}
+
+static bool coroutine_fn
+vu_message_read(VuDev *vu_dev, int conn_fd, VhostUserMsg *vmsg)
+{
+    struct iovec iov = {
+        .iov_base = (char *)vmsg,
+        .iov_len = VHOST_USER_HDR_SIZE,
+    };
+    int rc, read_bytes = 0;
+    Error *local_err = NULL;
+    /*
+     * Store fds/nfds returned from qio_channel_readv_full into
+     * temporary variables.
+     *
+     * VhostUserMsg is a packed structure, gcc will complain about passing
+     * pointer to a packed structure member if we pass &VhostUserMsg.fd_num
+     * and &VhostUserMsg.fds directly when calling qio_channel_readv_full,
+     * thus two temporary variables nfds and fds are used here.
+     */
+    size_t nfds = 0, nfds_t = 0;
+    const size_t max_fds = G_N_ELEMENTS(vmsg->fds);
+    int *fds_t = NULL;
+    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+    QIOChannel *ioc = server->ioc;
+
+    if (!ioc) {
+        error_report_err(local_err);
+        goto fail;
+    }
+
+    assert(qemu_in_coroutine());
+    do {
+        /*
+         * qio_channel_readv_full may have short reads, keeping calling it
+         * until getting VHOST_USER_HDR_SIZE or 0 bytes in total
+         */
+        rc = qio_channel_readv_full(ioc, &iov, 1, &fds_t, &nfds_t, &local_err);
+        if (rc < 0) {
+            if (rc == QIO_CHANNEL_ERR_BLOCK) {
+                qio_channel_yield(ioc, G_IO_IN);
+                continue;
+            } else {
+                error_report_err(local_err);
+                return false;
+            }
+        }
+        read_bytes += rc;
+        if (nfds_t > 0) {
+            if (nfds + nfds_t > max_fds) {
+                error_report("A maximum of %zu fds are allowed, "
+                             "however got %lu fds now",
+                             max_fds, nfds + nfds_t);
+                goto fail;
+            }
+            memcpy(vmsg->fds + nfds, fds_t,
+                   nfds_t *sizeof(vmsg->fds[0]));
+            nfds += nfds_t;
+            g_free(fds_t);
+        }
+        if (read_bytes == VHOST_USER_HDR_SIZE || rc == 0) {
+            break;
+        }
+        iov.iov_base = (char *)vmsg + read_bytes;
+        iov.iov_len = VHOST_USER_HDR_SIZE - read_bytes;
+    } while (true);
+
+    vmsg->fd_num = nfds;
+    /* qio_channel_readv_full will make socket fds blocking, unblock them */
+    vmsg_unblock_fds(vmsg);
+    if (vmsg->size > sizeof(vmsg->payload)) {
+        error_report("Error: too big message request: %d, "
+                     "size: vmsg->size: %u, "
+                     "while sizeof(vmsg->payload) = %zu",
+                     vmsg->request, vmsg->size, sizeof(vmsg->payload));
+        goto fail;
+    }
+
+    struct iovec iov_payload = {
+        .iov_base = (char *)&vmsg->payload,
+        .iov_len = vmsg->size,
+    };
+    if (vmsg->size) {
+        rc = qio_channel_readv_all_eof(ioc, &iov_payload, 1, &local_err);
+        if (rc == -1) {
+            error_report_err(local_err);
+            goto fail;
+        }
+    }
+
+    return true;
+
+fail:
+    vmsg_close_fds(vmsg);
+
+    return false;
+}
+
+
+static void vu_client_start(VuServer *server);
+static coroutine_fn void vu_client_trip(void *opaque)
+{
+    VuServer *server = opaque;
+
+    while (!server->aio_context_changed && server->sioc) {
+        server->processing_msg = true;
+        vu_dispatch(&server->vu_dev);
+        server->processing_msg = false;
+    }
+
+    if (server->aio_context_changed && server->sioc) {
+        server->aio_context_changed = false;
+        vu_client_start(server);
+    }
+}
+
+static void vu_client_start(VuServer *server)
+{
+    server->co_trip = qemu_coroutine_create(vu_client_trip, server);
+    aio_co_enter(server->ctx, server->co_trip);
+}
+
+/*
+ * a wrapper for vu_kick_cb
+ *
+ * since aio_dispatch can only pass one user data pointer to the
+ * callback function, pack VuDev and pvt into a struct. Then unpack it
+ * and pass them to vu_kick_cb
+ */
+static void kick_handler(void *opaque)
+{
+    VuFdWatch *vu_fd_watch = opaque;
+    vu_fd_watch->processing = true;
+    vu_fd_watch->cb(vu_fd_watch->vu_dev, 0, vu_fd_watch->pvt);
+    vu_fd_watch->processing = false;
+}
+
+
+static VuFdWatch *find_vu_fd_watch(VuServer *server, int fd)
+{
+
+    VuFdWatch *vu_fd_watch, *next;
+    QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
+        if (vu_fd_watch->fd == fd) {
+            return vu_fd_watch;
+        }
+    }
+    return NULL;
+}
+
+static void
+set_watch(VuDev *vu_dev, int fd, int vu_evt,
+          vu_watch_cb cb, void *pvt)
+{
+
+    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+    g_assert(vu_dev);
+    g_assert(fd >= 0);
+    g_assert(cb);
+
+    VuFdWatch *vu_fd_watch = find_vu_fd_watch(server, fd);
+
+    if (!vu_fd_watch) {
+        VuFdWatch *vu_fd_watch = g_new0(VuFdWatch, 1);
+
+        QTAILQ_INSERT_TAIL(&server->vu_fd_watches, vu_fd_watch, next);
+
+        vu_fd_watch->fd = fd;
+        vu_fd_watch->cb = cb;
+        qemu_set_nonblock(fd);
+        aio_set_fd_handler(server->ioc->ctx, fd, true, kick_handler,
+                           NULL, NULL, vu_fd_watch);
+        vu_fd_watch->vu_dev = vu_dev;
+        vu_fd_watch->pvt = pvt;
+    }
+}
+
+
+static void remove_watch(VuDev *vu_dev, int fd)
+{
+    VuServer *server;
+    g_assert(vu_dev);
+    g_assert(fd >= 0);
+
+    server = container_of(vu_dev, VuServer, vu_dev);
+
+    VuFdWatch *vu_fd_watch = find_vu_fd_watch(server, fd);
+
+    if (!vu_fd_watch) {
+        return;
+    }
+    aio_set_fd_handler(server->ioc->ctx, fd, true, NULL, NULL, NULL, NULL);
+
+    QTAILQ_REMOVE(&server->vu_fd_watches, vu_fd_watch, next);
+    g_free(vu_fd_watch);
+}
+
+
+static void vu_accept(QIONetListener *listener, QIOChannelSocket *sioc,
+                      gpointer opaque)
+{
+    VuServer *server = opaque;
+
+    if (server->sioc) {
+        warn_report("Only one vhost-user client is allowed to "
+                    "connect the server one time");
+        return;
+    }
+
+    if (!vu_init(&server->vu_dev, server->max_queues, sioc->fd, panic_cb,
+                 vu_message_read, set_watch, remove_watch, server->vu_iface)) {
+        error_report("Failed to initialize libvhost-user");
+        return;
+    }
+
+    /*
+     * Unset the callback function for network listener to make another
+     * vhost-user client keeping waiting until this client disconnects
+     */
+    qio_net_listener_set_client_func(server->listener,
+                                     NULL,
+                                     NULL,
+                                     NULL);
+    server->sioc = sioc;
+    /*
+     * Increase the object reference, so sioc will not freed by
+     * qio_net_listener_channel_func which will call object_unref(OBJECT(sioc))
+     */
+    object_ref(OBJECT(server->sioc));
+    qio_channel_set_name(QIO_CHANNEL(sioc), "vhost-user client");
+    server->ioc = QIO_CHANNEL(sioc);
+    object_ref(OBJECT(server->ioc));
+    qio_channel_attach_aio_context(server->ioc, server->ctx);
+    qio_channel_set_blocking(QIO_CHANNEL(server->sioc), false, NULL);
+    vu_client_start(server);
+}
+
+
+void vhost_user_server_stop(VuServer *server)
+{
+    if (server->sioc) {
+        close_client(server);
+    }
+
+    if (server->listener) {
+        qio_net_listener_disconnect(server->listener);
+        object_unref(OBJECT(server->listener));
+    }
+
+}
+
+void vhost_user_server_set_aio_context(VuServer *server, AioContext *ctx)
+{
+    VuFdWatch *vu_fd_watch, *next;
+    void *opaque = NULL;
+    IOHandler *io_read = NULL;
+    bool attach;
+
+    server->ctx = ctx ? ctx : qemu_get_aio_context();
+
+    if (!server->sioc) {
+        /* not yet serving any client*/
+        return;
+    }
+
+    if (ctx) {
+        qio_channel_attach_aio_context(server->ioc, ctx);
+        server->aio_context_changed = true;
+        io_read = kick_handler;
+        attach = true;
+    } else {
+        qio_channel_detach_aio_context(server->ioc);
+        /* server->ioc->ctx keeps the old AioConext */
+        ctx = server->ioc->ctx;
+        attach = false;
+    }
+
+    QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
+        if (vu_fd_watch->cb) {
+            opaque = attach ? vu_fd_watch : NULL;
+            aio_set_fd_handler(ctx, vu_fd_watch->fd, true,
+                               io_read, NULL, NULL,
+                               opaque);
+        }
+    }
+}
+
+
+bool vhost_user_server_start(VuServer *server,
+                             SocketAddress *socket_addr,
+                             AioContext *ctx,
+                             uint16_t max_queues,
+                             DevicePanicNotifierFn *device_panic_notifier,
+                             const VuDevIface *vu_iface,
+                             Error **errp)
+{
+    QIONetListener *listener = qio_net_listener_new();
+    if (qio_net_listener_open_sync(listener, socket_addr, 1,
+                                   errp) < 0) {
+        object_unref(OBJECT(listener));
+        return false;
+    }
+
+    /* zero out unspecified fileds */
+    *server = (VuServer) {
+        .listener              = listener,
+        .vu_iface              = vu_iface,
+        .max_queues            = max_queues,
+        .ctx                   = ctx,
+        .device_panic_notifier = device_panic_notifier,
+    };
+
+    qio_net_listener_set_name(server->listener, "vhost-user-backend-listener");
+
+    qio_net_listener_set_client_func(server->listener,
+                                     vu_accept,
+                                     server,
+                                     NULL);
+
+    QTAILQ_INIT(&server->vu_fd_watches);
+    return true;
+}
diff --git a/util/meson.build b/util/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/util/meson.build
+++ b/util/meson.build
@@ -XXX,XX +XXX,XX @@ if have_block
   util_ss.add(files('main-loop.c'))
   util_ss.add(files('nvdimm-utils.c'))
   util_ss.add(files('qemu-coroutine.c', 'qemu-coroutine-lock.c', 'qemu-coroutine-io.c'))
+  util_ss.add(when: 'CONFIG_LINUX', if_true: files('vhost-user-server.c'))
   util_ss.add(files('qemu-coroutine-sleep.c'))
   util_ss.add(files('qemu-co-shared-resource.c'))
   util_ss.add(files('thread-pool.c', 'qemu-timer.c'))
-- 
2.26.2

From: Coiby Xu <coiby.xu@gmail.com>

Move the constants from hw/core/qdev-properties.c to
util/block-helpers.h so that knowledge of the min/max values is

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Eduardo Habkost <ehabkost@redhat.com>
Message-id: 20200918080912.321299-5-coiby.xu@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 util/block-helpers.h             | 19 +++++++++++++
 hw/core/qdev-properties-system.c | 31 ++++-----------------
 util/block-helpers.c             | 46 ++++++++++++++++++++++++++++++++
 util/meson.build                 |  1 +
 4 files changed, 71 insertions(+), 26 deletions(-)
 create mode 100644 util/block-helpers.h
 create mode 100644 util/block-helpers.c

diff --git a/util/block-helpers.h b/util/block-helpers.h
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/util/block-helpers.h
@@ -XXX,XX +XXX,XX @@
+#ifndef BLOCK_HELPERS_H
+#define BLOCK_HELPERS_H
+
+#include "qemu/units.h"
+
+/* lower limit is sector size */
+#define MIN_BLOCK_SIZE          INT64_C(512)
+#define MIN_BLOCK_SIZE_STR      "512 B"
+/*
+ * upper limit is arbitrary, 2 MiB looks sufficient for all sensible uses, and
+ * matches qcow2 cluster size limit
+ */
+#define MAX_BLOCK_SIZE          (2 * MiB)
+#define MAX_BLOCK_SIZE_STR      "2 MiB"
+
+void check_block_size(const char *id, const char *name, int64_t value,
+                      Error **errp);
+
+#endif /* BLOCK_HELPERS_H */
diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c
index XXXXXXX..XXXXXXX 100644
--- a/hw/core/qdev-properties-system.c
+++ b/hw/core/qdev-properties-system.c
@@ -XXX,XX +XXX,XX @@
 #include "sysemu/blockdev.h"
 #include "net/net.h"
 #include "hw/pci/pci.h"
+#include "util/block-helpers.h"
 
 static bool check_prop_still_unset(DeviceState *dev, const char *name,
                                    const void *old_val, const char *new_val,
@@ -XXX,XX +XXX,XX @@ const PropertyInfo qdev_prop_losttickpolicy = {
 
 /* --- blocksize --- */
 
-/* lower limit is sector size */
-#define MIN_BLOCK_SIZE          512
-#define MIN_BLOCK_SIZE_STR      "512 B"
-/*
- * upper limit is arbitrary, 2 MiB looks sufficient for all sensible uses, and
- * matches qcow2 cluster size limit
- */
-#define MAX_BLOCK_SIZE          (2 * MiB)
-#define MAX_BLOCK_SIZE_STR      "2 MiB"
-
 static void set_blocksize(Object *obj, Visitor *v, const char *name,
                           void *opaque, Error **errp)
 {
@@ -XXX,XX +XXX,XX @@ static void set_blocksize(Object *obj, Visitor *v, const char *name,
     Property *prop = opaque;
     uint32_t *ptr = qdev_get_prop_ptr(dev, prop);
     uint64_t value;
+    Error *local_err = NULL;
 
     if (dev->realized) {
         qdev_prop_set_after_realize(dev, name, errp);
@@ -XXX,XX +XXX,XX @@ static void set_blocksize(Object *obj, Visitor *v, const char *name,
     if (!visit_type_size(v, name, &value, errp)) {
         return;
     }
-    /* value of 0 means "unset" */
-    if (value && (value < MIN_BLOCK_SIZE || value > MAX_BLOCK_SIZE)) {
-        error_setg(errp,
-                   "Property %s.%s doesn't take value %" PRIu64
-                   " (minimum: " MIN_BLOCK_SIZE_STR
-                   ", maximum: " MAX_BLOCK_SIZE_STR ")",
-                   dev->id ? : "", name, value);
+    check_block_size(dev->id ? : "", name, value, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
         return;
     }
-
-    /* We rely on power-of-2 blocksizes for bitmasks */
-    if ((value & (value - 1)) != 0) {
-        error_setg(errp,
-                  "Property %s.%s doesn't take value '%" PRId64 "', "
-                  "it's not a power of 2", dev->id ?: "", name, (int64_t)value);
-        return;
-    }
-
     *ptr = value;
 }
 
diff --git a/util/block-helpers.c b/util/block-helpers.c
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/util/block-helpers.c
@@ -XXX,XX +XXX,XX @@
+/*
+ * Block utility functions
+ *
+ * Copyright IBM, Corp. 2011
+ * Copyright (c) 2020 Coiby Xu <coiby.xu@gmail.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qapi/qmp/qerror.h"
+#include "block-helpers.h"
+
+/**
+ * check_block_size:
+ * @id: The unique ID of the object
+ * @name: The name of the property being validated
+ * @value: The block size in bytes
+ * @errp: A pointer to an area to store an error
+ *
+ * This function checks that the block size meets the following conditions:
+ * 1. At least MIN_BLOCK_SIZE
+ * 2. No larger than MAX_BLOCK_SIZE
+ * 3. A power of 2
+ */
+void check_block_size(const char *id, const char *name, int64_t value,
+                      Error **errp)
+{
+    /* value of 0 means "unset" */
+    if (value && (value < MIN_BLOCK_SIZE || value > MAX_BLOCK_SIZE)) {
+        error_setg(errp, QERR_PROPERTY_VALUE_OUT_OF_RANGE,
+                   id, name, value, MIN_BLOCK_SIZE, MAX_BLOCK_SIZE);
+        return;
+    }
+
+    /* We rely on power-of-2 blocksizes for bitmasks */
+    if ((value & (value - 1)) != 0) {
+        error_setg(errp,
+                   "Property %s.%s doesn't take value '%" PRId64
+                   "', it's not a power of 2",
+                   id, name, value);
+        return;
+    }
+}
diff --git a/util/meson.build b/util/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/util/meson.build
+++ b/util/meson.build
@@ -XXX,XX +XXX,XX @@ if have_block
   util_ss.add(files('nvdimm-utils.c'))
   util_ss.add(files('qemu-coroutine.c', 'qemu-coroutine-lock.c', 'qemu-coroutine-io.c'))
   util_ss.add(when: 'CONFIG_LINUX', if_true: files('vhost-user-server.c'))
+  util_ss.add(files('block-helpers.c'))
   util_ss.add(files('qemu-coroutine-sleep.c'))
   util_ss.add(files('qemu-co-shared-resource.c'))
   util_ss.add(files('thread-pool.c', 'qemu-timer.c'))
-- 
2.26.2

From: Coiby Xu <coiby.xu@gmail.com>

By making use of libvhost-user, block device drive can be shared to
the connected vhost-user client. Only one client can connect to the
server one time.

Since vhost-user-server needs a block drive to be created first, delay
the creation of this object.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20200918080912.321299-6-coiby.xu@gmail.com
[Shorten "vhost_user_blk_server" string to "vhost_user_blk" to avoid the
following compiler warning:
../block/export/vhost-user-blk-server.c:178:50: error: ‘%s’ directive output truncated writing 21 bytes into a region of size 20 [-Werror=format-truncation=]
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/export/vhost-user-blk-server.h |  36 ++
 block/export/vhost-user-blk-server.c | 661 +++++++++++++++++++++++++++
 softmmu/vl.c                         |   4 +
 block/meson.build                    |   1 +
 4 files changed, 702 insertions(+)
 create mode 100644 block/export/vhost-user-blk-server.h
 create mode 100644 block/export/vhost-user-blk-server.c

diff --git a/block/export/vhost-user-blk-server.h b/block/export/vhost-user-blk-server.h
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/block/export/vhost-user-blk-server.h
@@ -XXX,XX +XXX,XX @@
+/*
+ * Sharing QEMU block devices via vhost-user protocal
+ *
+ * Copyright (c) Coiby Xu <coiby.xu@gmail.com>.
+ * Copyright (c) 2020 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ */
+
+#ifndef VHOST_USER_BLK_SERVER_H
+#define VHOST_USER_BLK_SERVER_H
+#include "util/vhost-user-server.h"
+
+typedef struct VuBlockDev VuBlockDev;
+#define TYPE_VHOST_USER_BLK_SERVER "vhost-user-blk-server"
+#define VHOST_USER_BLK_SERVER(obj) \
+   OBJECT_CHECK(VuBlockDev, obj, TYPE_VHOST_USER_BLK_SERVER)
+
+/* vhost user block device */
+struct VuBlockDev {
+    Object parent_obj;
+    char *node_name;
+    SocketAddress *addr;
+    AioContext *ctx;
+    VuServer vu_server;
+    bool running;
+    uint32_t blk_size;
+    BlockBackend *backend;
+    QIOChannelSocket *sioc;
+    QTAILQ_ENTRY(VuBlockDev) next;
+    struct virtio_blk_config blkcfg;
+    bool writable;
+};
+
+#endif /* VHOST_USER_BLK_SERVER_H */
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@
+/*
+ * Sharing QEMU block devices via vhost-user protocal
+ *
+ * Parts of the code based on nbd/server.c.
+ *
+ * Copyright (c) Coiby Xu <coiby.xu@gmail.com>.
+ * Copyright (c) 2020 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ */
+#include "qemu/osdep.h"
+#include "block/block.h"
+#include "vhost-user-blk-server.h"
+#include "qapi/error.h"
+#include "qom/object_interfaces.h"
+#include "sysemu/block-backend.h"
+#include "util/block-helpers.h"
+
+enum {
+    VHOST_USER_BLK_MAX_QUEUES = 1,
+};
+struct virtio_blk_inhdr {
+    unsigned char status;
+};
+
+typedef struct VuBlockReq {
+    VuVirtqElement *elem;
+    int64_t sector_num;
+    size_t size;
+    struct virtio_blk_inhdr *in;
+    struct virtio_blk_outhdr out;
+    VuServer *server;
+    struct VuVirtq *vq;
+} VuBlockReq;
+
+static void vu_block_req_complete(VuBlockReq *req)
+{
+    VuDev *vu_dev = &req->server->vu_dev;
+
+    /* IO size with 1 extra status byte */
+    vu_queue_push(vu_dev, req->vq, req->elem, req->size + 1);
+    vu_queue_notify(vu_dev, req->vq);
+
+    if (req->elem) {
+        free(req->elem);
+    }
+
+    g_free(req);
+}
+
+static VuBlockDev *get_vu_block_device_by_server(VuServer *server)
+{
+    return container_of(server, VuBlockDev, vu_server);
+}
+
+static int coroutine_fn
+vu_block_discard_write_zeroes(VuBlockReq *req, struct iovec *iov,
+                              uint32_t iovcnt, uint32_t type)
+{
+    struct virtio_blk_discard_write_zeroes desc;
+    ssize_t size = iov_to_buf(iov, iovcnt, 0, &desc, sizeof(desc));
+    if (unlikely(size != sizeof(desc))) {
+        error_report("Invalid size %ld, expect %ld", size, sizeof(desc));
+        return -EINVAL;
+    }
+
+    VuBlockDev *vdev_blk = get_vu_block_device_by_server(req->server);
+    uint64_t range[2] = { le64_to_cpu(desc.sector) << 9,
+                          le32_to_cpu(desc.num_sectors) << 9 };
+    if (type == VIRTIO_BLK_T_DISCARD) {
+        if (blk_co_pdiscard(vdev_blk->backend, range[0], range[1]) == 0) {
+            return 0;
+        }
+    } else if (type == VIRTIO_BLK_T_WRITE_ZEROES) {
+        if (blk_co_pwrite_zeroes(vdev_blk->backend,
+                                 range[0], range[1], 0) == 0) {
+            return 0;
+        }
+    }
+
+    return -EINVAL;
+}
+
+static void coroutine_fn vu_block_flush(VuBlockReq *req)
+{
+    VuBlockDev *vdev_blk = get_vu_block_device_by_server(req->server);
+    BlockBackend *backend = vdev_blk->backend;
+    blk_co_flush(backend);
+}
+
+struct req_data {
+    VuServer *server;
+    VuVirtq *vq;
+    VuVirtqElement *elem;
+};
+
+static void coroutine_fn vu_block_virtio_process_req(void *opaque)
+{
+    struct req_data *data = opaque;
+    VuServer *server = data->server;
+    VuVirtq *vq = data->vq;
+    VuVirtqElement *elem = data->elem;
+    uint32_t type;
+    VuBlockReq *req;
+
+    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+    BlockBackend *backend = vdev_blk->backend;
+
+    struct iovec *in_iov = elem->in_sg;
+    struct iovec *out_iov = elem->out_sg;
+    unsigned in_num = elem->in_num;
+    unsigned out_num = elem->out_num;
+    /* refer to hw/block/virtio_blk.c */
+    if (elem->out_num < 1 || elem->in_num < 1) {
+        error_report("virtio-blk request missing headers");
+        free(elem);
+        return;
+    }
+
+    req = g_new0(VuBlockReq, 1);
+    req->server = server;
+    req->vq = vq;
+    req->elem = elem;
+
+    if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out,
+                            sizeof(req->out)) != sizeof(req->out))) {
+        error_report("virtio-blk request outhdr too short");
+        goto err;
+    }
+
+    iov_discard_front(&out_iov, &out_num, sizeof(req->out));
+
+    if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) {
+        error_report("virtio-blk request inhdr too short");
+        goto err;
+    }
+
+    /* We always touch the last byte, so just see how big in_iov is.  */
+    req->in = (void *)in_iov[in_num - 1].iov_base
+              + in_iov[in_num - 1].iov_len
+              - sizeof(struct virtio_blk_inhdr);
+    iov_discard_back(in_iov, &in_num, sizeof(struct virtio_blk_inhdr));
+
+    type = le32_to_cpu(req->out.type);
+    switch (type & ~VIRTIO_BLK_T_BARRIER) {
+    case VIRTIO_BLK_T_IN:
+    case VIRTIO_BLK_T_OUT: {
+        ssize_t ret = 0;
+        bool is_write = type & VIRTIO_BLK_T_OUT;
+        req->sector_num = le64_to_cpu(req->out.sector);
+
+        int64_t offset = req->sector_num * vdev_blk->blk_size;
+        QEMUIOVector qiov;
+        if (is_write) {
+            qemu_iovec_init_external(&qiov, out_iov, out_num);
+            ret = blk_co_pwritev(backend, offset, qiov.size,
+                                 &qiov, 0);
+        } else {
+            qemu_iovec_init_external(&qiov, in_iov, in_num);
+            ret = blk_co_preadv(backend, offset, qiov.size,
+                                &qiov, 0);
+        }
+        if (ret >= 0) {
+            req->in->status = VIRTIO_BLK_S_OK;
+        } else {
+            req->in->status = VIRTIO_BLK_S_IOERR;
+        }
+        break;
+    }
+    case VIRTIO_BLK_T_FLUSH:
+        vu_block_flush(req);
+        req->in->status = VIRTIO_BLK_S_OK;
+        break;
+    case VIRTIO_BLK_T_GET_ID: {
+        size_t size = MIN(iov_size(&elem->in_sg[0], in_num),
+                          VIRTIO_BLK_ID_BYTES);
+        snprintf(elem->in_sg[0].iov_base, size, "%s", "vhost_user_blk");
+        req->in->status = VIRTIO_BLK_S_OK;
+        req->size = elem->in_sg[0].iov_len;
+        break;
+    }
+    case VIRTIO_BLK_T_DISCARD:
+    case VIRTIO_BLK_T_WRITE_ZEROES: {
+        int rc;
+        rc = vu_block_discard_write_zeroes(req, &elem->out_sg[1],
+                                           out_num, type);
+        if (rc == 0) {
+            req->in->status = VIRTIO_BLK_S_OK;
+        } else {
+            req->in->status = VIRTIO_BLK_S_IOERR;
+        }
+        break;
+    }
+    default:
+        req->in->status = VIRTIO_BLK_S_UNSUPP;
+        break;
+    }
+
+    vu_block_req_complete(req);
+    return;
+
+err:
+    free(elem);
+    g_free(req);
+    return;
+}
+
+static void vu_block_process_vq(VuDev *vu_dev, int idx)
+{
+    VuServer *server;
+    VuVirtq *vq;
+    struct req_data *req_data;
+
+    server = container_of(vu_dev, VuServer, vu_dev);
+    assert(server);
+
+    vq = vu_get_queue(vu_dev, idx);
+    assert(vq);
+    VuVirtqElement *elem;
+    while (1) {
+        elem = vu_queue_pop(vu_dev, vq, sizeof(VuVirtqElement) +
+                                    sizeof(VuBlockReq));
+        if (elem) {
+            req_data = g_new0(struct req_data, 1);
+            req_data->server = server;
+            req_data->vq = vq;
+            req_data->elem = elem;
+            Coroutine *co = qemu_coroutine_create(vu_block_virtio_process_req,
+                                                  req_data);
+            aio_co_enter(server->ioc->ctx, co);
+        } else {
+            break;
+        }
+    }
+}
+
+static void vu_block_queue_set_started(VuDev *vu_dev, int idx, bool started)
+{
+    VuVirtq *vq;
+
+    assert(vu_dev);
+
+    vq = vu_get_queue(vu_dev, idx);
+    vu_set_queue_handler(vu_dev, vq, started ? vu_block_process_vq : NULL);
+}
+
+static uint64_t vu_block_get_features(VuDev *dev)
+{
+    uint64_t features;
+    VuServer *server = container_of(dev, VuServer, vu_dev);
+    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+    features = 1ull << VIRTIO_BLK_F_SIZE_MAX |
+               1ull << VIRTIO_BLK_F_SEG_MAX |
+               1ull << VIRTIO_BLK_F_TOPOLOGY |
+               1ull << VIRTIO_BLK_F_BLK_SIZE |
+               1ull << VIRTIO_BLK_F_FLUSH |
+               1ull << VIRTIO_BLK_F_DISCARD |
+               1ull << VIRTIO_BLK_F_WRITE_ZEROES |
+               1ull << VIRTIO_BLK_F_CONFIG_WCE |
+               1ull << VIRTIO_F_VERSION_1 |
+               1ull << VIRTIO_RING_F_INDIRECT_DESC |
+               1ull << VIRTIO_RING_F_EVENT_IDX |
+               1ull << VHOST_USER_F_PROTOCOL_FEATURES;
+
+    if (!vdev_blk->writable) {
+        features |= 1ull << VIRTIO_BLK_F_RO;
+    }
+
+    return features;
+}
+
+static uint64_t vu_block_get_protocol_features(VuDev *dev)
+{
+    return 1ull << VHOST_USER_PROTOCOL_F_CONFIG |
+           1ull << VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD;
+}
+
+static int
+vu_block_get_config(VuDev *vu_dev, uint8_t *config, uint32_t len)
+{
+    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+    memcpy(config, &vdev_blk->blkcfg, len);
+
+    return 0;
+}
+
+static int
+vu_block_set_config(VuDev *vu_dev, const uint8_t *data,
+                    uint32_t offset, uint32_t size, uint32_t flags)
+{
+    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+    uint8_t wce;
+
+    /* don't support live migration */
+    if (flags != VHOST_SET_CONFIG_TYPE_MASTER) {
+        return -EINVAL;
+    }
+
+    if (offset != offsetof(struct virtio_blk_config, wce) ||
+        size != 1) {
+        return -EINVAL;
+    }
+
+    wce = *data;
+    vdev_blk->blkcfg.wce = wce;
+    blk_set_enable_write_cache(vdev_blk->backend, wce);
+    return 0;
+}
+
+/*
+ * When the client disconnects, it sends a VHOST_USER_NONE request
+ * and vu_process_message will simple call exit which cause the VM
+ * to exit abruptly.
+ * To avoid this issue,  process VHOST_USER_NONE request ahead
+ * of vu_process_message.
+ *
+ */
+static int vu_block_process_msg(VuDev *dev, VhostUserMsg *vmsg, int *do_reply)
+{
+    if (vmsg->request == VHOST_USER_NONE) {
+        dev->panic(dev, "disconnect");
+        return true;
+    }
+    return false;
+}
+
+static const VuDevIface vu_block_iface = {
+    .get_features          = vu_block_get_features,
+    .queue_set_started     = vu_block_queue_set_started,
+    .get_protocol_features = vu_block_get_protocol_features,
+    .get_config            = vu_block_get_config,
+    .set_config            = vu_block_set_config,
+    .process_msg           = vu_block_process_msg,
+};
+
+static void blk_aio_attached(AioContext *ctx, void *opaque)
+{
+    VuBlockDev *vub_dev = opaque;
+    aio_context_acquire(ctx);
+    vhost_user_server_set_aio_context(&vub_dev->vu_server, ctx);
+    aio_context_release(ctx);
+}
+
+static void blk_aio_detach(void *opaque)
+{
+    VuBlockDev *vub_dev = opaque;
+    AioContext *ctx = vub_dev->vu_server.ctx;
+    aio_context_acquire(ctx);
+    vhost_user_server_set_aio_context(&vub_dev->vu_server, NULL);
+    aio_context_release(ctx);
+}
+
+static void
+vu_block_initialize_config(BlockDriverState *bs,
+                           struct virtio_blk_config *config, uint32_t blk_size)
+{
+    config->capacity = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
+    config->blk_size = blk_size;
+    config->size_max = 0;
+    config->seg_max = 128 - 2;
+    config->min_io_size = 1;
+    config->opt_io_size = 1;
+    config->num_queues = VHOST_USER_BLK_MAX_QUEUES;
+    config->max_discard_sectors = 32768;
+    config->max_discard_seg = 1;
+    config->discard_sector_alignment = config->blk_size >> 9;
+    config->max_write_zeroes_sectors = 32768;
+    config->max_write_zeroes_seg = 1;
+}
+
+static VuBlockDev *vu_block_init(VuBlockDev *vu_block_device, Error **errp)
+{
+
+    BlockBackend *blk;
+    Error *local_error = NULL;
+    const char *node_name = vu_block_device->node_name;
+    bool writable = vu_block_device->writable;
+    uint64_t perm = BLK_PERM_CONSISTENT_READ;
+    int ret;
+
+    AioContext *ctx;
+
+    BlockDriverState *bs = bdrv_lookup_bs(node_name, node_name, &local_error);
+
+    if (!bs) {
+        error_propagate(errp, local_error);
+        return NULL;
+    }
+
+    if (bdrv_is_read_only(bs)) {
+        writable = false;
+    }
+
+    if (writable) {
+        perm |= BLK_PERM_WRITE;
+    }
+
+    ctx = bdrv_get_aio_context(bs);
+    aio_context_acquire(ctx);
+    bdrv_invalidate_cache(bs, NULL);
+    aio_context_release(ctx);
+
+    /*
+     * Don't allow resize while the vhost user server is running,
+     * otherwise we don't care what happens with the node.
+     */
+    blk = blk_new(bdrv_get_aio_context(bs), perm,
+                  BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED |
+                  BLK_PERM_WRITE | BLK_PERM_GRAPH_MOD);
+    ret = blk_insert_bs(blk, bs, errp);
+
+    if (ret < 0) {
+        goto fail;
+    }
+
+    blk_set_enable_write_cache(blk, false);
+
+    blk_set_allow_aio_context_change(blk, true);
+
+    vu_block_device->blkcfg.wce = 0;
+    vu_block_device->backend = blk;
+    if (!vu_block_device->blk_size) {
+        vu_block_device->blk_size = BDRV_SECTOR_SIZE;
+    }
+    vu_block_device->blkcfg.blk_size = vu_block_device->blk_size;
+    blk_set_guest_block_size(blk, vu_block_device->blk_size);
+    vu_block_initialize_config(bs, &vu_block_device->blkcfg,
+                                   vu_block_device->blk_size);
+    return vu_block_device;
+
+fail:
+    blk_unref(blk);
+    return NULL;
+}
+
+static void vu_block_deinit(VuBlockDev *vu_block_device)
+{
+    if (vu_block_device->backend) {
+        blk_remove_aio_context_notifier(vu_block_device->backend, blk_aio_attached,
+                                        blk_aio_detach, vu_block_device);
+    }
+
+    blk_unref(vu_block_device->backend);
+}
+
+static void vhost_user_blk_server_stop(VuBlockDev *vu_block_device)
+{
+    vhost_user_server_stop(&vu_block_device->vu_server);
+    vu_block_deinit(vu_block_device);
+}
+
+static void vhost_user_blk_server_start(VuBlockDev *vu_block_device,
+                                        Error **errp)
+{
+    AioContext *ctx;
+    SocketAddress *addr = vu_block_device->addr;
+
+    if (!vu_block_init(vu_block_device, errp)) {
+        return;
+    }
+
+    ctx = bdrv_get_aio_context(blk_bs(vu_block_device->backend));
+
+    if (!vhost_user_server_start(&vu_block_device->vu_server, addr, ctx,
+                                 VHOST_USER_BLK_MAX_QUEUES,
+                                 NULL, &vu_block_iface,
+                                 errp)) {
+        goto error;
+    }
+
+    blk_add_aio_context_notifier(vu_block_device->backend, blk_aio_attached,
+                                 blk_aio_detach, vu_block_device);
+    vu_block_device->running = true;
+    return;
+
+ error:
+    vu_block_deinit(vu_block_device);
+}
+
+static bool vu_prop_modifiable(VuBlockDev *vus, Error **errp)
+{
+    if (vus->running) {
+            error_setg(errp, "The property can't be modified "
+                       "while the server is running");
+            return false;
+    }
+    return true;
+}
+
+static void vu_set_node_name(Object *obj, const char *value, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+
+    if (!vu_prop_modifiable(vus, errp)) {
+        return;
+    }
+
+    if (vus->node_name) {
+        g_free(vus->node_name);
+    }
+
+    vus->node_name = g_strdup(value);
+}
+
+static char *vu_get_node_name(Object *obj, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+    return g_strdup(vus->node_name);
+}
+
+static void free_socket_addr(SocketAddress *addr)
+{
+        g_free(addr->u.q_unix.path);
+        g_free(addr);
+}
+
+static void vu_set_unix_socket(Object *obj, const char *value,
+                               Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+
+    if (!vu_prop_modifiable(vus, errp)) {
+        return;
+    }
+
+    if (vus->addr) {
+        free_socket_addr(vus->addr);
+    }
+
+    SocketAddress *addr = g_new0(SocketAddress, 1);
+    addr->type = SOCKET_ADDRESS_TYPE_UNIX;
+    addr->u.q_unix.path = g_strdup(value);
+    vus->addr = addr;
+}
+
+static char *vu_get_unix_socket(Object *obj, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+    return g_strdup(vus->addr->u.q_unix.path);
+}
+
+static bool vu_get_block_writable(Object *obj, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+    return vus->writable;
+}
+
+static void vu_set_block_writable(Object *obj, bool value, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+
+    if (!vu_prop_modifiable(vus, errp)) {
+            return;
+    }
+
+    vus->writable = value;
+}
+
+static void vu_get_blk_size(Object *obj, Visitor *v, const char *name,
+                            void *opaque, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+    uint32_t value = vus->blk_size;
+
+    visit_type_uint32(v, name, &value, errp);
+}
+
+static void vu_set_blk_size(Object *obj, Visitor *v, const char *name,
+                            void *opaque, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+
+    Error *local_err = NULL;
+    uint32_t value;
+
+    if (!vu_prop_modifiable(vus, errp)) {
+            return;
+    }
+
+    visit_type_uint32(v, name, &value, &local_err);
+    if (local_err) {
+        goto out;
+    }
+
+    check_block_size(object_get_typename(obj), name, value, &local_err);
+    if (local_err) {
+        goto out;
+    }
+
+    vus->blk_size = value;
+
+out:
+    error_propagate(errp, local_err);
+}
+
+static void vhost_user_blk_server_instance_finalize(Object *obj)
+{
+    VuBlockDev *vub = VHOST_USER_BLK_SERVER(obj);
+
+    vhost_user_blk_server_stop(vub);
+
+    /*
+     * Unlike object_property_add_str, object_class_property_add_str
+     * doesn't have a release method. Thus manual memory freeing is
+     * needed.
+     */
+    free_socket_addr(vub->addr);
+    g_free(vub->node_name);
+}
+
+static void vhost_user_blk_server_complete(UserCreatable *obj, Error **errp)
+{
+    VuBlockDev *vub = VHOST_USER_BLK_SERVER(obj);
+
+    vhost_user_blk_server_start(vub, errp);
+}
+
+static void vhost_user_blk_server_class_init(ObjectClass *klass,
+                                             void *class_data)
+{
+    UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
+    ucc->complete = vhost_user_blk_server_complete;
+
+    object_class_property_add_bool(klass, "writable",
+                                   vu_get_block_writable,
+                                   vu_set_block_writable);
+
+    object_class_property_add_str(klass, "node-name",
+                                  vu_get_node_name,
+                                  vu_set_node_name);
+
+    object_class_property_add_str(klass, "unix-socket",
+                                  vu_get_unix_socket,
+                                  vu_set_unix_socket);
+
+    object_class_property_add(klass, "logical-block-size", "uint32",
+                              vu_get_blk_size, vu_set_blk_size,
+                              NULL, NULL);
+}
+
+static const TypeInfo vhost_user_blk_server_info = {
+    .name = TYPE_VHOST_USER_BLK_SERVER,
+    .parent = TYPE_OBJECT,
+    .instance_size = sizeof(VuBlockDev),
+    .instance_finalize = vhost_user_blk_server_instance_finalize,
+    .class_init = vhost_user_blk_server_class_init,
+    .interfaces = (InterfaceInfo[]) {
+        {TYPE_USER_CREATABLE},
+        {}
+    },
+};
+
+static void vhost_user_blk_server_register_types(void)
+{
+    type_register_static(&vhost_user_blk_server_info);
+}
+
+type_init(vhost_user_blk_server_register_types)
diff --git a/softmmu/vl.c b/softmmu/vl.c
index XXXXXXX..XXXXXXX 100644
--- a/softmmu/vl.c
+++ b/softmmu/vl.c
@@ -XXX,XX +XXX,XX @@ static bool object_create_initial(const char *type, QemuOpts *opts)
     }
 #endif
 
+    /* Reason: vhost-user-blk-server property "node-name" */
+    if (g_str_equal(type, "vhost-user-blk-server")) {
+        return false;
+    }
     /*
      * Reason: filter-* property "netdev" etc.
      */
diff --git a/block/meson.build b/block/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/block/meson.build
+++ b/block/meson.build
@@ -XXX,XX +XXX,XX @@ block_ss.add(when: 'CONFIG_WIN32', if_true: files('file-win32.c', 'win32-aio.c')
 block_ss.add(when: 'CONFIG_POSIX', if_true: [files('file-posix.c'), coref, iokit])
 block_ss.add(when: 'CONFIG_LIBISCSI', if_true: files('iscsi-opts.c'))
 block_ss.add(when: 'CONFIG_LINUX', if_true: files('nvme.c'))
+block_ss.add(when: 'CONFIG_LINUX', if_true: files('export/vhost-user-blk-server.c', '../contrib/libvhost-user/libvhost-user.c'))
 block_ss.add(when: 'CONFIG_REPLICATION', if_true: files('replication.c'))
 block_ss.add(when: 'CONFIG_SHEEPDOG', if_true: files('sheepdog.c'))
 block_ss.add(when: ['CONFIG_LINUX_AIO', libaio], if_true: files('linux-aio.c'))
-- 
2.26.2

From: Coiby Xu <coiby.xu@gmail.com>

This test case has the same tests as tests/virtio-blk-test.c except for
tests have block_resize. Since vhost-user server can only server one
client one time, two instances of vhost-user-blk-server are started by
qemu-storage-daemon for the hotplug test.

In order to not block scripts/tap-driver.pl, vhost-user-blk-server will
send "quit" command to qemu-storage-daemon's QMP monitor. So a function
is added to libqtest.c to establish socket connection with socket
server.

Suggested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20200918080912.321299-7-coiby.xu@gmail.com
[Update meson.build to only test when CONFIG_TOOLS has built
qemu-storage-daemon. This prevents CI failures with --disable-tools.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 tests/qtest/libqos/libqtest.h       |  17 +
 tests/qtest/libqos/vhost-user-blk.h |  48 ++
 tests/qtest/libqos/vhost-user-blk.c | 129 +++++
 tests/qtest/libqtest.c              |  36 +-
 tests/qtest/vhost-user-blk-test.c   | 751 ++++++++++++++++++++++++++++
 tests/qtest/libqos/meson.build      |   1 +
 tests/qtest/meson.build             |   4 +-
 7 files changed, 983 insertions(+), 3 deletions(-)
 create mode 100644 tests/qtest/libqos/vhost-user-blk.h
 create mode 100644 tests/qtest/libqos/vhost-user-blk.c
 create mode 100644 tests/qtest/vhost-user-blk-test.c

diff --git a/tests/qtest/libqos/libqtest.h b/tests/qtest/libqos/libqtest.h
index XXXXXXX..XXXXXXX 100644
--- a/tests/qtest/libqos/libqtest.h
+++ b/tests/qtest/libqos/libqtest.h
@@ -XXX,XX +XXX,XX @@ void qtest_qmp_send(QTestState *s, const char *fmt, ...)
 void qtest_qmp_send_raw(QTestState *s, const char *fmt, ...)
     GCC_FMT_ATTR(2, 3);
 
+/**
+ * qtest_socket_client:
+ * @server_socket_path: the socket server's path
+ *
+ * Connect to a socket server.
+ */
+int qtest_socket_client(char *server_socket_path);
+
+/**
+ * qtest_create_state_with_qmp_fd:
+ * @fd: socket fd
+ *
+ * Wrap socket fd in QTestState to make use of qtest_qmp*
+ * functions
+ */
+QTestState *qtest_create_state_with_qmp_fd(int fd);
+
 /**
  * qtest_vqmp_fds:
  * @s: #QTestState instance to operate on.
diff --git a/tests/qtest/libqos/vhost-user-blk.h b/tests/qtest/libqos/vhost-user-blk.h
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/tests/qtest/libqos/vhost-user-blk.h
@@ -XXX,XX +XXX,XX @@
+/*
+ * libqos driver framework
+ *
+ * Based on tests/qtest/libqos/virtio-blk.c
+ *
+ * Copyright (c) 2020 Coiby Xu <coiby.xu@gmail.com>
+ *
+ * Copyright (c) 2018 Emanuele Giuseppe Esposito <e.emanuelegiuseppe@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2 as published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>
+ */
+
+#ifndef TESTS_LIBQOS_VHOST_USER_BLK_H
+#define TESTS_LIBQOS_VHOST_USER_BLK_H
+
+#include "qgraph.h"
+#include "virtio.h"
+#include "virtio-pci.h"
+
+typedef struct QVhostUserBlk QVhostUserBlk;
+typedef struct QVhostUserBlkPCI QVhostUserBlkPCI;
+typedef struct QVhostUserBlkDevice QVhostUserBlkDevice;
+
+struct QVhostUserBlk {
+    QVirtioDevice *vdev;
+};
+
+struct QVhostUserBlkPCI {
+    QVirtioPCIDevice pci_vdev;
+    QVhostUserBlk blk;
+};
+
+struct QVhostUserBlkDevice {
+    QOSGraphObject obj;
+    QVhostUserBlk blk;
+};
+
+#endif
diff --git a/tests/qtest/libqos/vhost-user-blk.c b/tests/qtest/libqos/vhost-user-blk.c
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/tests/qtest/libqos/vhost-user-blk.c
@@ -XXX,XX +XXX,XX @@
+/*
+ * libqos driver framework
+ *
+ * Based on tests/qtest/libqos/virtio-blk.c
+ *
+ * Copyright (c) 2020 Coiby Xu <coiby.xu@gmail.com>
+ *
+ * Copyright (c) 2018 Emanuele Giuseppe Esposito <e.emanuelegiuseppe@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1 as published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>
+ */
+
+#include "qemu/osdep.h"
+#include "libqtest.h"
+#include "qemu/module.h"
+#include "standard-headers/linux/virtio_blk.h"
+#include "vhost-user-blk.h"
+
+#define PCI_SLOT                0x04
+#define PCI_FN                  0x00
+
+/* virtio-blk-device */
+static void *qvhost_user_blk_get_driver(QVhostUserBlk *v_blk,
+                                    const char *interface)
+{
+    if (!g_strcmp0(interface, "vhost-user-blk")) {
+        return v_blk;
+    }
+    if (!g_strcmp0(interface, "virtio")) {
+        return v_blk->vdev;
+    }
+
+    fprintf(stderr, "%s not present in vhost-user-blk-device\n", interface);
+    g_assert_not_reached();
+}
+
+static void *qvhost_user_blk_device_get_driver(void *object,
+                                           const char *interface)
+{
+    QVhostUserBlkDevice *v_blk = object;
+    return qvhost_user_blk_get_driver(&v_blk->blk, interface);
+}
+
+static void *vhost_user_blk_device_create(void *virtio_dev,
+                                      QGuestAllocator *t_alloc,
+                                      void *addr)
+{
+    QVhostUserBlkDevice *vhost_user_blk = g_new0(QVhostUserBlkDevice, 1);
+    QVhostUserBlk *interface = &vhost_user_blk->blk;
+
+    interface->vdev = virtio_dev;
+
+    vhost_user_blk->obj.get_driver = qvhost_user_blk_device_get_driver;
+
+    return &vhost_user_blk->obj;
+}
+
+/* virtio-blk-pci */
+static void *qvhost_user_blk_pci_get_driver(void *object, const char *interface)
+{
+    QVhostUserBlkPCI *v_blk = object;
+    if (!g_strcmp0(interface, "pci-device")) {
+        return v_blk->pci_vdev.pdev;
+    }
+    return qvhost_user_blk_get_driver(&v_blk->blk, interface);
+}
+
+static void *vhost_user_blk_pci_create(void *pci_bus, QGuestAllocator *t_alloc,
+                                      void *addr)
+{
+    QVhostUserBlkPCI *vhost_user_blk = g_new0(QVhostUserBlkPCI, 1);
+    QVhostUserBlk *interface = &vhost_user_blk->blk;
+    QOSGraphObject *obj = &vhost_user_blk->pci_vdev.obj;
+
+    virtio_pci_init(&vhost_user_blk->pci_vdev, pci_bus, addr);
+    interface->vdev = &vhost_user_blk->pci_vdev.vdev;
+
+    g_assert_cmphex(interface->vdev->device_type, ==, VIRTIO_ID_BLOCK);
+
+    obj->get_driver = qvhost_user_blk_pci_get_driver;
+
+    return obj;
+}
+
+static void vhost_user_blk_register_nodes(void)
+{
+    /*
+     * FIXME: every test using these two nodes needs to setup a
+     * -drive,id=drive0 otherwise QEMU is not going to start.
+     * Therefore, we do not include "produces" edge for virtio
+     * and pci-device yet.
+     */
+
+    char *arg = g_strdup_printf("id=drv0,chardev=char1,addr=%x.%x",
+                                PCI_SLOT, PCI_FN);
+
+    QPCIAddress addr = {
+        .devfn = QPCI_DEVFN(PCI_SLOT, PCI_FN),
+    };
+
+    QOSGraphEdgeOptions opts = { };
+
+    /* virtio-blk-device */
+    /** opts.extra_device_opts = "drive=drive0"; */
+    qos_node_create_driver("vhost-user-blk-device", vhost_user_blk_device_create);
+    qos_node_consumes("vhost-user-blk-device", "virtio-bus", &opts);
+    qos_node_produces("vhost-user-blk-device", "vhost-user-blk");
+
+    /* virtio-blk-pci */
+    opts.extra_device_opts = arg;
+    add_qpci_address(&opts, &addr);
+    qos_node_create_driver("vhost-user-blk-pci", vhost_user_blk_pci_create);
+    qos_node_consumes("vhost-user-blk-pci", "pci-bus", &opts);
+    qos_node_produces("vhost-user-blk-pci", "vhost-user-blk");
+
+    g_free(arg);
+}
+
+libqos_init(vhost_user_blk_register_nodes);
diff --git a/tests/qtest/libqtest.c b/tests/qtest/libqtest.c
index XXXXXXX..XXXXXXX 100644
--- a/tests/qtest/libqtest.c
+++ b/tests/qtest/libqtest.c
@@ -XXX,XX +XXX,XX @@
  * Copyright IBM, Corp. 2012
  * Copyright Red Hat, Inc. 2012
  * Copyright SUSE LINUX Products GmbH 2013
+ * Copyright Copyright (c) Coiby Xu
  *
  * Authors:
  *  Anthony Liguori   <aliguori@us.ibm.com>
  *  Paolo Bonzini     <pbonzini@redhat.com>
  *  Andreas Färber    <afaerber@suse.de>
+ *  Coiby Xu          <coiby.xu@gmail.com>
  *
  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  * See the COPYING file in the top-level directory.
@@ -XXX,XX +XXX,XX @@ typedef struct QTestClientTransportOps {
     QTestRecvFn     recv_line; /* for receiving qtest command responses */
 } QTestTransportOps;
 
-struct QTestState
-{
+struct QTestState {
     int fd;
     int qmp_fd;
     pid_t qemu_pid;  /* our child QEMU process */
@@ -XXX,XX +XXX,XX @@ QDict *qtest_qmp_receive(QTestState *s)
     return qmp_fd_receive(s->qmp_fd);
 }
 
+QTestState *qtest_create_state_with_qmp_fd(int fd)
+{
+    QTestState *qmp_test_state = g_new0(QTestState, 1);
+    qmp_test_state->qmp_fd = fd;
+    return qmp_test_state;
+}
+
+int qtest_socket_client(char *server_socket_path)
+{
+    struct sockaddr_un serv_addr;
+    int sock;
+    int ret;
+    int retries = 0;
+    sock = socket(PF_UNIX, SOCK_STREAM, 0);
+    g_assert_cmpint(sock, !=, -1);
+    serv_addr.sun_family = AF_UNIX;
+    snprintf(serv_addr.sun_path, sizeof(serv_addr.sun_path), "%s",
+             server_socket_path);
+
+    for (retries = 0; retries < 3; retries++) {
+        ret = connect(sock, (struct sockaddr *)&serv_addr, sizeof(serv_addr));
+        if (ret == 0) {
+            break;
+        }
+        g_usleep(G_USEC_PER_SEC);
+    }
+
+    g_assert_cmpint(ret, ==, 0);
+    return sock;
+}
+
 /**
  * Allow users to send a message without waiting for the reply,
  * in the case that they choose to discard all replies up until
diff --git a/tests/qtest/vhost-user-blk-test.c b/tests/qtest/vhost-user-blk-test.c
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/tests/qtest/vhost-user-blk-test.c
@@ -XXX,XX +XXX,XX @@
+/*
+ * QTest testcase for Vhost-user Block Device
+ *
+ * Based on tests/qtest//virtio-blk-test.c
+
+ * Copyright (c) 2014 SUSE LINUX Products GmbH
+ * Copyright (c) 2014 Marc Marí
+ * Copyright (c) 2020 Coiby Xu
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "libqtest-single.h"
+#include "qemu/bswap.h"
+#include "qemu/module.h"
+#include "standard-headers/linux/virtio_blk.h"
+#include "standard-headers/linux/virtio_pci.h"
+#include "libqos/qgraph.h"
+#include "libqos/vhost-user-blk.h"
+#include "libqos/libqos-pc.h"
+
+#define TEST_IMAGE_SIZE         (64 * 1024 * 1024)
+#define QVIRTIO_BLK_TIMEOUT_US  (30 * 1000 * 1000)
+#define PCI_SLOT_HP             0x06
+
+typedef struct QVirtioBlkReq {
+    uint32_t type;
+    uint32_t ioprio;
+    uint64_t sector;
+    char *data;
+    uint8_t status;
+} QVirtioBlkReq;
+
+#ifdef HOST_WORDS_BIGENDIAN
+static const bool host_is_big_endian = true;
+#else
+static const bool host_is_big_endian; /* false */
+#endif
+
+static inline void virtio_blk_fix_request(QVirtioDevice *d, QVirtioBlkReq *req)
+{
+    if (qvirtio_is_big_endian(d) != host_is_big_endian) {
+        req->type = bswap32(req->type);
+        req->ioprio = bswap32(req->ioprio);
+        req->sector = bswap64(req->sector);
+    }
+}
+
+static inline void virtio_blk_fix_dwz_hdr(QVirtioDevice *d,
+    struct virtio_blk_discard_write_zeroes *dwz_hdr)
+{
+    if (qvirtio_is_big_endian(d) != host_is_big_endian) {
+        dwz_hdr->sector = bswap64(dwz_hdr->sector);
+        dwz_hdr->num_sectors = bswap32(dwz_hdr->num_sectors);
+        dwz_hdr->flags = bswap32(dwz_hdr->flags);
+    }
+}
+
+static uint64_t virtio_blk_request(QGuestAllocator *alloc, QVirtioDevice *d,
+                                   QVirtioBlkReq *req, uint64_t data_size)
+{
+    uint64_t addr;
+    uint8_t status = 0xFF;
+    QTestState *qts = global_qtest;
+
+    switch (req->type) {
+    case VIRTIO_BLK_T_IN:
+    case VIRTIO_BLK_T_OUT:
+        g_assert_cmpuint(data_size % 512, ==, 0);
+        break;
+    case VIRTIO_BLK_T_DISCARD:
+    case VIRTIO_BLK_T_WRITE_ZEROES:
+        g_assert_cmpuint(data_size %
+                         sizeof(struct virtio_blk_discard_write_zeroes), ==, 0);
+        break;
+    default:
+        g_assert_cmpuint(data_size, ==, 0);
+    }
+
+    addr = guest_alloc(alloc, sizeof(*req) + data_size);
+
+    virtio_blk_fix_request(d, req);
+
+    qtest_memwrite(qts, addr, req, 16);
+    qtest_memwrite(qts, addr + 16, req->data, data_size);
+    qtest_memwrite(qts, addr + 16 + data_size, &status, sizeof(status));
+
+    return addr;
+}
+
+/* Returns the request virtqueue so the caller can perform further tests */
+static QVirtQueue *test_basic(QVirtioDevice *dev, QGuestAllocator *alloc)
+{
+    QVirtioBlkReq req;
+    uint64_t req_addr;
+    uint64_t capacity;
+    uint64_t features;
+    uint32_t free_head;
+    uint8_t status;
+    char *data;
+    QTestState *qts = global_qtest;
+    QVirtQueue *vq;
+
+    features = qvirtio_get_features(dev);
+    features = features & ~(QVIRTIO_F_BAD_FEATURE |
+                    (1u << VIRTIO_RING_F_INDIRECT_DESC) |
+                    (1u << VIRTIO_RING_F_EVENT_IDX) |
+                    (1u << VIRTIO_BLK_F_SCSI));
+    qvirtio_set_features(dev, features);
+
+    capacity = qvirtio_config_readq(dev, 0);
+    g_assert_cmpint(capacity, ==, TEST_IMAGE_SIZE / 512);
+
+    vq = qvirtqueue_setup(dev, alloc, 0);
+
+    qvirtio_set_driver_ok(dev);
+
+    /* Write and read with 3 descriptor layout */
+    /* Write request */
+    req.type = VIRTIO_BLK_T_OUT;
+    req.ioprio = 1;
+    req.sector = 0;
+    req.data = g_malloc0(512);
+    strcpy(req.data, "TEST");
+
+    req_addr = virtio_blk_request(alloc, dev, &req, 512);
+
+    g_free(req.data);
+
+    free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
+    qvirtqueue_add(qts, vq, req_addr + 16, 512, false, true);
+    qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
+
+    qvirtqueue_kick(qts, dev, vq, free_head);
+
+    qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
+                           QVIRTIO_BLK_TIMEOUT_US);
+    status = readb(req_addr + 528);
+    g_assert_cmpint(status, ==, 0);
+
+    guest_free(alloc, req_addr);
+
+    /* Read request */
+    req.type = VIRTIO_BLK_T_IN;
+    req.ioprio = 1;
+    req.sector = 0;
+    req.data = g_malloc0(512);
+
+    req_addr = virtio_blk_request(alloc, dev, &req, 512);
+
+    g_free(req.data);
+
+    free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
+    qvirtqueue_add(qts, vq, req_addr + 16, 512, true, true);
+    qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
+
+    qvirtqueue_kick(qts, dev, vq, free_head);
+
+    qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
+                           QVIRTIO_BLK_TIMEOUT_US);
+    status = readb(req_addr + 528);
+    g_assert_cmpint(status, ==, 0);
+
+    data = g_malloc0(512);
+    qtest_memread(qts, req_addr + 16, data, 512);
+    g_assert_cmpstr(data, ==, "TEST");
+    g_free(data);
+
+    guest_free(alloc, req_addr);
+
+    if (features & (1u << VIRTIO_BLK_F_WRITE_ZEROES)) {
+        struct virtio_blk_discard_write_zeroes dwz_hdr;
+        void *expected;
+
+        /*
+         * WRITE_ZEROES request on the same sector of previous test where
+         * we wrote "TEST".
+         */
+        req.type = VIRTIO_BLK_T_WRITE_ZEROES;
+        req.data = (char *) &dwz_hdr;
+        dwz_hdr.sector = 0;
+        dwz_hdr.num_sectors = 1;
+        dwz_hdr.flags = 0;
+
+        virtio_blk_fix_dwz_hdr(dev, &dwz_hdr);
+
+        req_addr = virtio_blk_request(alloc, dev, &req, sizeof(dwz_hdr));
+
+        free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
+        qvirtqueue_add(qts, vq, req_addr + 16, sizeof(dwz_hdr), false, true);
+        qvirtqueue_add(qts, vq, req_addr + 16 + sizeof(dwz_hdr), 1, true,
+                       false);
+
+        qvirtqueue_kick(qts, dev, vq, free_head);
+
+        qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
+                               QVIRTIO_BLK_TIMEOUT_US);
+        status = readb(req_addr + 16 + sizeof(dwz_hdr));
+        g_assert_cmpint(status, ==, 0);
+
+        guest_free(alloc, req_addr);
+
+        /* Read request to check if the sector contains all zeroes */
+        req.type = VIRTIO_BLK_T_IN;
+        req.ioprio = 1;
+        req.sector = 0;
+        req.data = g_malloc0(512);
+
+        req_addr = virtio_blk_request(alloc, dev, &req, 512);
+
+        g_free(req.data);
+
+        free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
+        qvirtqueue_add(qts, vq, req_addr + 16, 512, true, true);
+        qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
+
+        qvirtqueue_kick(qts, dev, vq, free_head);
+
+        qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
+                               QVIRTIO_BLK_TIMEOUT_US);
+        status = readb(req_addr + 528);
+        g_assert_cmpint(status, ==, 0);
+
+        data = g_malloc(512);
+        expected = g_malloc0(512);
+        qtest_memread(qts, req_addr + 16, data, 512);
+        g_assert_cmpmem(data, 512, expected, 512);
+        g_free(expected);
+        g_free(data);
+
+        guest_free(alloc, req_addr);
+    }
+
+    if (features & (1u << VIRTIO_BLK_F_DISCARD)) {
+        struct virtio_blk_discard_write_zeroes dwz_hdr;
+
+        req.type = VIRTIO_BLK_T_DISCARD;
+        req.data = (char *) &dwz_hdr;
+        dwz_hdr.sector = 0;
+        dwz_hdr.num_sectors = 1;
+        dwz_hdr.flags = 0;
+
+        virtio_blk_fix_dwz_hdr(dev, &dwz_hdr);
+
+        req_addr = virtio_blk_request(alloc, dev, &req, sizeof(dwz_hdr));
+
+        free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
+        qvirtqueue_add(qts, vq, req_addr + 16, sizeof(dwz_hdr), false, true);
+        qvirtqueue_add(qts, vq, req_addr + 16 + sizeof(dwz_hdr),
+                       1, true, false);
+
+        qvirtqueue_kick(qts, dev, vq, free_head);
+
+        qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
+                               QVIRTIO_BLK_TIMEOUT_US);
+        status = readb(req_addr + 16 + sizeof(dwz_hdr));
+        g_assert_cmpint(status, ==, 0);
+
+        guest_free(alloc, req_addr);
+    }
+
+    if (features & (1u << VIRTIO_F_ANY_LAYOUT)) {
+        /* Write and read with 2 descriptor layout */
+        /* Write request */
+        req.type = VIRTIO_BLK_T_OUT;
+        req.ioprio = 1;
+        req.sector = 1;
+        req.data = g_malloc0(512);
+        strcpy(req.data, "TEST");
+
+        req_addr = virtio_blk_request(alloc, dev, &req, 512);
+
+        g_free(req.data);
+
+        free_head = qvirtqueue_add(qts, vq, req_addr, 528, false, true);
+        qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
+        qvirtqueue_kick(qts, dev, vq, free_head);
+
+        qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
+                               QVIRTIO_BLK_TIMEOUT_US);
+        status = readb(req_addr + 528);
+        g_assert_cmpint(status, ==, 0);
+
+        guest_free(alloc, req_addr);
+
+        /* Read request */
+        req.type = VIRTIO_BLK_T_IN;
+        req.ioprio = 1;
+        req.sector = 1;
+        req.data = g_malloc0(512);
+
+        req_addr = virtio_blk_request(alloc, dev, &req, 512);
+
+        g_free(req.data);
+
+        free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
+        qvirtqueue_add(qts, vq, req_addr + 16, 513, true, false);
+
+        qvirtqueue_kick(qts, dev, vq, free_head);
+
+        qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
+                               QVIRTIO_BLK_TIMEOUT_US);
+        status = readb(req_addr + 528);
+        g_assert_cmpint(status, ==, 0);
+
+        data = g_malloc0(512);
+        qtest_memread(qts, req_addr + 16, data, 512);
+        g_assert_cmpstr(data, ==, "TEST");
+        g_free(data);
+
+        guest_free(alloc, req_addr);
+    }
+
+    return vq;
+}
+
+static void basic(void *obj, void *data, QGuestAllocator *t_alloc)
+{
+    QVhostUserBlk *blk_if = obj;
+    QVirtQueue *vq;
+
+    vq = test_basic(blk_if->vdev, t_alloc);
+    qvirtqueue_cleanup(blk_if->vdev->bus, vq, t_alloc);
+
+}
+
+static void indirect(void *obj, void *u_data, QGuestAllocator *t_alloc)
+{
+    QVirtQueue *vq;
+    QVhostUserBlk *blk_if = obj;
+    QVirtioDevice *dev = blk_if->vdev;
+    QVirtioBlkReq req;
+    QVRingIndirectDesc *indirect;
+    uint64_t req_addr;
+    uint64_t capacity;
+    uint64_t features;
+    uint32_t free_head;
+    uint8_t status;
+    char *data;
+    QTestState *qts = global_qtest;
+
+    features = qvirtio_get_features(dev);
+    g_assert_cmphex(features & (1u << VIRTIO_RING_F_INDIRECT_DESC), !=, 0);
+    features = features & ~(QVIRTIO_F_BAD_FEATURE |
+                            (1u << VIRTIO_RING_F_EVENT_IDX) |
+                            (1u << VIRTIO_BLK_F_SCSI));
+    qvirtio_set_features(dev, features);
+
+    capacity = qvirtio_config_readq(dev, 0);
+    g_assert_cmpint(capacity, ==, TEST_IMAGE_SIZE / 512);
+
+    vq = qvirtqueue_setup(dev, t_alloc, 0);
+    qvirtio_set_driver_ok(dev);
+
+    /* Write request */
+    req.type = VIRTIO_BLK_T_OUT;
+    req.ioprio = 1;
+    req.sector = 0;
+    req.data = g_malloc0(512);
+    strcpy(req.data, "TEST");
+
+    req_addr = virtio_blk_request(t_alloc, dev, &req, 512);
+
+    g_free(req.data);
+
+    indirect = qvring_indirect_desc_setup(qts, dev, t_alloc, 2);
+    qvring_indirect_desc_add(dev, qts, indirect, req_addr, 528, false);
+    qvring_indirect_desc_add(dev, qts, indirect, req_addr + 528, 1, true);
+    free_head = qvirtqueue_add_indirect(qts, vq, indirect);
+    qvirtqueue_kick(qts, dev, vq, free_head);
+
+    qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
+                           QVIRTIO_BLK_TIMEOUT_US);
+    status = readb(req_addr + 528);
+    g_assert_cmpint(status, ==, 0);
+
+    g_free(indirect);
+    guest_free(t_alloc, req_addr);
+
+    /* Read request */
+    req.type = VIRTIO_BLK_T_IN;
+    req.ioprio = 1;
+    req.sector = 0;
+    req.data = g_malloc0(512);
+    strcpy(req.data, "TEST");
+
+    req_addr = virtio_blk_request(t_alloc, dev, &req, 512);
+
+    g_free(req.data);
+
+    indirect = qvring_indirect_desc_setup(qts, dev, t_alloc, 2);
+    qvring_indirect_desc_add(dev, qts, indirect, req_addr, 16, false);
+    qvring_indirect_desc_add(dev, qts, indirect, req_addr + 16, 513, true);
+    free_head = qvirtqueue_add_indirect(qts, vq, indirect);
+    qvirtqueue_kick(qts, dev, vq, free_head);
+
+    qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
+                           QVIRTIO_BLK_TIMEOUT_US);
+    status = readb(req_addr + 528);
+    g_assert_cmpint(status, ==, 0);
+
+    data = g_malloc0(512);
+    qtest_memread(qts, req_addr + 16, data, 512);
+    g_assert_cmpstr(data, ==, "TEST");
+    g_free(data);
+
+    g_free(indirect);
+    guest_free(t_alloc, req_addr);
+    qvirtqueue_cleanup(dev->bus, vq, t_alloc);
+}
+
+static void idx(void *obj, void *u_data, QGuestAllocator *t_alloc)
+{
+    QVirtQueue *vq;
+    QVhostUserBlkPCI *blk = obj;
+    QVirtioPCIDevice *pdev = &blk->pci_vdev;
+    QVirtioDevice *dev = &pdev->vdev;
+    QVirtioBlkReq req;
+    uint64_t req_addr;
+    uint64_t capacity;
+    uint64_t features;
+    uint32_t free_head;
+    uint32_t write_head;
+    uint32_t desc_idx;
+    uint8_t status;
+    char *data;
+    QOSGraphObject *blk_object = obj;
+    QPCIDevice *pci_dev = blk_object->get_driver(blk_object, "pci-device");
+    QTestState *qts = global_qtest;
+
+    if (qpci_check_buggy_msi(pci_dev)) {
+        return;
+    }
+
+    qpci_msix_enable(pdev->pdev);
+    qvirtio_pci_set_msix_configuration_vector(pdev, t_alloc, 0);
+
+    features = qvirtio_get_features(dev);
+    features = features & ~(QVIRTIO_F_BAD_FEATURE |
+                            (1u << VIRTIO_RING_F_INDIRECT_DESC) |
+                            (1u << VIRTIO_F_NOTIFY_ON_EMPTY) |
+                            (1u << VIRTIO_BLK_F_SCSI));
+    qvirtio_set_features(dev, features);
+
+    capacity = qvirtio_config_readq(dev, 0);
+    g_assert_cmpint(capacity, ==, TEST_IMAGE_SIZE / 512);
+
+    vq = qvirtqueue_setup(dev, t_alloc, 0);
+    qvirtqueue_pci_msix_setup(pdev, (QVirtQueuePCI *)vq, t_alloc, 1);
+
+    qvirtio_set_driver_ok(dev);
+
+    /* Write request */
+    req.type = VIRTIO_BLK_T_OUT;
+    req.ioprio = 1;
+    req.sector = 0;
+    req.data = g_malloc0(512);
+    strcpy(req.data, "TEST");
+
+    req_addr = virtio_blk_request(t_alloc, dev, &req, 512);
+
+    g_free(req.data);
+
+    free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
+    qvirtqueue_add(qts, vq, req_addr + 16, 512, false, true);
+    qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
+    qvirtqueue_kick(qts, dev, vq, free_head);
+
+    qvirtio_wait_used_elem(qts, dev, vq, free_head, NULL,
+                           QVIRTIO_BLK_TIMEOUT_US);
+
+    /* Write request */
+    req.type = VIRTIO_BLK_T_OUT;
+    req.ioprio = 1;
+    req.sector = 1;
+    req.data = g_malloc0(512);
+    strcpy(req.data, "TEST");
+
+    req_addr = virtio_blk_request(t_alloc, dev, &req, 512);
+
+    g_free(req.data);
+
+    /* Notify after processing the third request */
+    qvirtqueue_set_used_event(qts, vq, 2);
+    free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
+    qvirtqueue_add(qts, vq, req_addr + 16, 512, false, true);
+    qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
+    qvirtqueue_kick(qts, dev, vq, free_head);
+    write_head = free_head;
+
+    /* No notification expected */
+    status = qvirtio_wait_status_byte_no_isr(qts, dev,
+                                             vq, req_addr + 528,
+                                             QVIRTIO_BLK_TIMEOUT_US);
+    g_assert_cmpint(status, ==, 0);
+
+    guest_free(t_alloc, req_addr);
+
+    /* Read request */
+    req.type = VIRTIO_BLK_T_IN;
+    req.ioprio = 1;
+    req.sector = 1;
+    req.data = g_malloc0(512);
+
+    req_addr = virtio_blk_request(t_alloc, dev, &req, 512);
+
+    g_free(req.data);
+
+    free_head = qvirtqueue_add(qts, vq, req_addr, 16, false, true);
+    qvirtqueue_add(qts, vq, req_addr + 16, 512, true, true);
+    qvirtqueue_add(qts, vq, req_addr + 528, 1, true, false);
+
+    qvirtqueue_kick(qts, dev, vq, free_head);
+
+    /* We get just one notification for both requests */
+    qvirtio_wait_used_elem(qts, dev, vq, write_head, NULL,
+                           QVIRTIO_BLK_TIMEOUT_US);
+    g_assert(qvirtqueue_get_buf(qts, vq, &desc_idx, NULL));
+    g_assert_cmpint(desc_idx, ==, free_head);
+
+    status = readb(req_addr + 528);
+    g_assert_cmpint(status, ==, 0);
+
+    data = g_malloc0(512);
+    qtest_memread(qts, req_addr + 16, data, 512);
+    g_assert_cmpstr(data, ==, "TEST");
+    g_free(data);
+
+    guest_free(t_alloc, req_addr);
+
+    /* End test */
+    qpci_msix_disable(pdev->pdev);
+
+    qvirtqueue_cleanup(dev->bus, vq, t_alloc);
+}
+
+static void pci_hotplug(void *obj, void *data, QGuestAllocator *t_alloc)
+{
+    QVirtioPCIDevice *dev1 = obj;
+    QVirtioPCIDevice *dev;
+    QTestState *qts = dev1->pdev->bus->qts;
+
+    /* plug secondary disk */
+    qtest_qmp_device_add(qts, "vhost-user-blk-pci", "drv1",
+                         "{'addr': %s, 'chardev': 'char2'}",
+                         stringify(PCI_SLOT_HP) ".0");
+
+    dev = virtio_pci_new(dev1->pdev->bus,
+                         &(QPCIAddress) { .devfn = QPCI_DEVFN(PCI_SLOT_HP, 0)
+                                        });
+    g_assert_nonnull(dev);
+    g_assert_cmpint(dev->vdev.device_type, ==, VIRTIO_ID_BLOCK);
+    qvirtio_pci_device_disable(dev);
+    qos_object_destroy((QOSGraphObject *)dev);
+
+    /* unplug secondary disk */
+    qpci_unplug_acpi_device_test(qts, "drv1", PCI_SLOT_HP);
+}
+
+/*
+ * Check that setting the vring addr on a non-existent virtqueue does
+ * not crash.
+ */
+static void test_nonexistent_virtqueue(void *obj, void *data,
+                                       QGuestAllocator *t_alloc)
+{
+    QVhostUserBlkPCI *blk = obj;
+    QVirtioPCIDevice *pdev = &blk->pci_vdev;
+    QPCIBar bar0;
+    QPCIDevice *dev;
+
+    dev = qpci_device_find(pdev->pdev->bus, QPCI_DEVFN(4, 0));
+    g_assert(dev != NULL);
+    qpci_device_enable(dev);
+
+    bar0 = qpci_iomap(dev, 0, NULL);
+
+    qpci_io_writeb(dev, bar0, VIRTIO_PCI_QUEUE_SEL, 2);
+    qpci_io_writel(dev, bar0, VIRTIO_PCI_QUEUE_PFN, 1);
+
+    g_free(dev);
+}
+
+static const char *qtest_qemu_storage_daemon_binary(void)
+{
+    const char *qemu_storage_daemon_bin;
+
+    qemu_storage_daemon_bin = getenv("QTEST_QEMU_STORAGE_DAEMON_BINARY");
+    if (!qemu_storage_daemon_bin) {
+        fprintf(stderr, "Environment variable "
+                        "QTEST_QEMU_STORAGE_DAEMON_BINARY required\n");
+        exit(0);
+    }
+
+    return qemu_storage_daemon_bin;
+}
+
+static void drive_destroy(void *path)
+{
+    unlink(path);
+    g_free(path);
+    qos_invalidate_command_line();
+}
+
+static char *drive_create(void)
+{
+    int fd, ret;
+    /** vhost-user-blk won't recognize drive located in /tmp */
+    char *t_path = g_strdup("qtest.XXXXXX");
+
+    /** Create a temporary raw image */
+    fd = mkstemp(t_path);
+    g_assert_cmpint(fd, >=, 0);
+    ret = ftruncate(fd, TEST_IMAGE_SIZE);
+    g_assert_cmpint(ret, ==, 0);
+    close(fd);
+
+    g_test_queue_destroy(drive_destroy, t_path);
+    return t_path;
+}
+
+static char sock_path_tempate[] = "/tmp/qtest.vhost_user_blk.XXXXXX";
+static char qmp_sock_path_tempate[] = "/tmp/qtest.vhost_user_blk.qmp.XXXXXX";
+
+static void quit_storage_daemon(void *qmp_test_state)
+{
+    const char quit_str[] = "{ 'execute': 'quit' }";
+
+    /* Before quiting storate-daemon, quit qemu to avoid dubious messages */
+    qobject_unref(qtest_qmp(global_qtest, quit_str));
+
+    /*
+     * Give storage-daemon enough time to wake up&terminate
+     * vu_client_trip coroutine so the Coroutine object could
+     * be cleaned up. Otherwise LeakSanitizer would complain
+     * about memory leaks.
+     */
+    g_usleep(1000);
+
+    qobject_unref(qtest_qmp((QTestState *)qmp_test_state, quit_str));
+    g_free(qmp_test_state);
+}
+
+static char *start_vhost_user_blk(GString *cmd_line, int vus_instances)
+{
+    const char *vhost_user_blk_bin = qtest_qemu_storage_daemon_binary();
+    int fd, qmp_fd, i;
+    QTestState *qmp_test_state;
+    gchar *img_path;
+    char *sock_path = NULL;
+    char *qmp_sock_path = g_strdup(qmp_sock_path_tempate);
+    GString *storage_daemon_command = g_string_new(NULL);
+
+    qmp_fd = mkstemp(qmp_sock_path);
+    g_assert_cmpint(qmp_fd, >=, 0);
+    g_test_queue_destroy(drive_destroy, qmp_sock_path);
+
+    g_string_append_printf(storage_daemon_command,
+            "exec %s "
+            "--chardev socket,id=qmp,path=%s,server,nowait --monitor chardev=qmp ",
+            vhost_user_blk_bin, qmp_sock_path);
+
+    g_string_append_printf(cmd_line,
+            " -object memory-backend-memfd,id=mem,size=128M,share=on -numa node,memdev=mem ");
+
+    for (i = 0; i < vus_instances; i++) {
+        sock_path = g_strdup(sock_path_tempate);
+        fd = mkstemp(sock_path);
+        g_assert_cmpint(fd, >=, 0);
+        g_test_queue_destroy(drive_destroy, sock_path);
+        /* create image file */
+        img_path = drive_create();
+        g_string_append_printf(storage_daemon_command,
+            "--blockdev driver=file,node-name=disk%d,filename=%s "
+            "--object vhost-user-blk-server,id=disk%d,unix-socket=%s,"
+            "node-name=disk%i,writable=on ",
+            i, img_path, i, sock_path, i);
+
+        g_string_append_printf(cmd_line, "-chardev socket,id=char%d,path=%s ",
+                               i + 1, sock_path);
+    }
+
+    g_test_message("starting vhost-user backend: %s",
+                   storage_daemon_command->str);
+    pid_t pid = fork();
+    if (pid == 0) {
+        execlp("/bin/sh", "sh", "-c", storage_daemon_command->str, NULL);
+        exit(1);
+    }
+    g_string_free(storage_daemon_command, true);
+
+    qmp_test_state = qtest_create_state_with_qmp_fd(
+                             qtest_socket_client(qmp_sock_path));
+    /*
+     * Ask qemu-storage-daemon to quit so it
+     * will not block scripts/tap-driver.pl.
+     */
+    g_test_queue_destroy(quit_storage_daemon, qmp_test_state);
+
+    qobject_unref(qtest_qmp(qmp_test_state, "{'execute': 'qmp_capabilities'}"));
+    return sock_path;
+}
+
+static void *vhost_user_blk_test_setup(GString *cmd_line, void *arg)
+{
+    start_vhost_user_blk(cmd_line, 1);
+    return arg;
+}
+
+/*
+ * Setup for hotplug.
+ *
+ * Since vhost-user server only serves one vhost-user client one time,
+ * another exprot
+ *
+ */
+static void *vhost_user_blk_hotplug_test_setup(GString *cmd_line, void *arg)
+{
+    /* "-chardev socket,id=char2" is used for pci_hotplug*/
+    start_vhost_user_blk(cmd_line, 2);
+    return arg;
+}
+
+static void register_vhost_user_blk_test(void)
+{
+    QOSGraphTestOptions opts = {
+        .before = vhost_user_blk_test_setup,
+    };
+
+    /*
+     * tests for vhost-user-blk and vhost-user-blk-pci
+     * The tests are borrowed from tests/virtio-blk-test.c. But some tests
+     * regarding block_resize don't work for vhost-user-blk.
+     * vhost-user-blk device doesn't have -drive, so tests containing
+     * block_resize are also abandoned,
+     *  - config
+     *  - resize
+     */
+    qos_add_test("basic", "vhost-user-blk", basic, &opts);
+    qos_add_test("indirect", "vhost-user-blk", indirect, &opts);
+    qos_add_test("idx", "vhost-user-blk-pci", idx, &opts);
+    qos_add_test("nxvirtq", "vhost-user-blk-pci",
+                 test_nonexistent_virtqueue, &opts);
+
+    opts.before = vhost_user_blk_hotplug_test_setup;
+    qos_add_test("hotplug", "vhost-user-blk-pci", pci_hotplug, &opts);
+}
+
+libqos_init(register_vhost_user_blk_test);
diff --git a/tests/qtest/libqos/meson.build b/tests/qtest/libqos/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/tests/qtest/libqos/meson.build
+++ b/tests/qtest/libqos/meson.build
@@ -XXX,XX +XXX,XX @@ libqos_srcs = files('../libqtest.c',
         'virtio-9p.c',
         'virtio-balloon.c',
         'virtio-blk.c',
+        'vhost-user-blk.c',
         'virtio-mmio.c',
         'virtio-net.c',
         'virtio-pci.c',
diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/tests/qtest/meson.build
+++ b/tests/qtest/meson.build
@@ -XXX,XX +XXX,XX @@ qos_test_ss.add(
 )
 qos_test_ss.add(when: 'CONFIG_VIRTFS', if_true: files('virtio-9p-test.c'))
 qos_test_ss.add(when: 'CONFIG_VHOST_USER', if_true: files('vhost-user-test.c'))
+qos_test_ss.add(when: ['CONFIG_LINUX', 'CONFIG_TOOLS'], if_true: files('vhost-user-blk-test.c'))
 
 extra_qtest_deps = {
   'bios-tables-test': [io],
@@ -XXX,XX +XXX,XX @@ foreach dir : target_dirs
   endif
   qtest_env.set('G_TEST_DBUS_DAEMON', meson.source_root() / 'tests/dbus-vmstate-daemon.sh')
   qtest_env.set('QTEST_QEMU_BINARY', './qemu-system-' + target_base)
-  
+  qtest_env.set('QTEST_QEMU_STORAGE_DAEMON_BINARY', './storage-daemon/qemu-storage-daemon')
+
   foreach test : qtests
     # Executables are shared across targets, declare them only the first time we
     # encounter them
-- 
2.26.2

Explicitly deleting watches is not necessary since libvhost-user calls
remove_watch() during vu_deinit(). Add an assertion to check this
though.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200924151549.913737-5-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 util/vhost-user-server.c | 19 ++++---------------
 1 file changed, 4 insertions(+), 15 deletions(-)

diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@ static void close_client(VuServer *server)
     /* When this is set vu_client_trip will stop new processing vhost-user message */
     server->sioc = NULL;
 
-    VuFdWatch *vu_fd_watch, *next;
-    QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
-        aio_set_fd_handler(server->ioc->ctx, vu_fd_watch->fd, true, NULL,
-                           NULL, NULL, NULL);
-    }
-
-    while (!QTAILQ_EMPTY(&server->vu_fd_watches)) {
-        QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
-            if (!vu_fd_watch->processing) {
-                QTAILQ_REMOVE(&server->vu_fd_watches, vu_fd_watch, next);
-                g_free(vu_fd_watch);
-            }
-        }
-    }
-
     while (server->processing_msg) {
         if (server->ioc->read_coroutine) {
             server->ioc->read_coroutine = NULL;
@@ -XXX,XX +XXX,XX @@ static void close_client(VuServer *server)
     }
 
     vu_deinit(&server->vu_dev);
+
+    /* vu_deinit() should have called remove_watch() */
+    assert(QTAILQ_EMPTY(&server->vu_fd_watches));
+
     object_unref(OBJECT(sioc));
     object_unref(OBJECT(server->ioc));
 }
-- 
2.26.2

Only one struct is needed per request. Drop req_data and the separate
VuBlockReq instance. Instead let vu_queue_pop() allocate everything at
once.

This fixes the req_data memory leak in vu_block_virtio_process_req().

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200924151549.913737-6-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/export/vhost-user-blk-server.c | 68 +++++++++-------------------
 1 file changed, 21 insertions(+), 47 deletions(-)

diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.c
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@ struct virtio_blk_inhdr {
 };
 
 typedef struct VuBlockReq {
-    VuVirtqElement *elem;
+    VuVirtqElement elem;
     int64_t sector_num;
     size_t size;
     struct virtio_blk_inhdr *in;
@@ -XXX,XX +XXX,XX @@ static void vu_block_req_complete(VuBlockReq *req)
     VuDev *vu_dev = &req->server->vu_dev;
 
     /* IO size with 1 extra status byte */
-    vu_queue_push(vu_dev, req->vq, req->elem, req->size + 1);
+    vu_queue_push(vu_dev, req->vq, &req->elem, req->size + 1);
     vu_queue_notify(vu_dev, req->vq);
 
-    if (req->elem) {
-        free(req->elem);
-    }
-
-    g_free(req);
+    free(req);
 }
 
 static VuBlockDev *get_vu_block_device_by_server(VuServer *server)
@@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_flush(VuBlockReq *req)
     blk_co_flush(backend);
 }
 
-struct req_data {
-    VuServer *server;
-    VuVirtq *vq;
-    VuVirtqElement *elem;
-};
-
 static void coroutine_fn vu_block_virtio_process_req(void *opaque)
 {
-    struct req_data *data = opaque;
-    VuServer *server = data->server;
-    VuVirtq *vq = data->vq;
-    VuVirtqElement *elem = data->elem;
+    VuBlockReq *req = opaque;
+    VuServer *server = req->server;
+    VuVirtqElement *elem = &req->elem;
     uint32_t type;
-    VuBlockReq *req;
 
     VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
     BlockBackend *backend = vdev_blk->backend;
@@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
     struct iovec *out_iov = elem->out_sg;
     unsigned in_num = elem->in_num;
     unsigned out_num = elem->out_num;
+
     /* refer to hw/block/virtio_blk.c */
     if (elem->out_num < 1 || elem->in_num < 1) {
         error_report("virtio-blk request missing headers");
-        free(elem);
-        return;
+        goto err;
     }
 
-    req = g_new0(VuBlockReq, 1);
-    req->server = server;
-    req->vq = vq;
-    req->elem = elem;
-
     if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out,
                             sizeof(req->out)) != sizeof(req->out))) {
         error_report("virtio-blk request outhdr too short");
@@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
 
 err:
     free(elem);
-    g_free(req);
-    return;
 }
 
 static void vu_block_process_vq(VuDev *vu_dev, int idx)
 {
-    VuServer *server;
-    VuVirtq *vq;
-    struct req_data *req_data;
+    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+    VuVirtq *vq = vu_get_queue(vu_dev, idx);
 
-    server = container_of(vu_dev, VuServer, vu_dev);
-    assert(server);
-
-    vq = vu_get_queue(vu_dev, idx);
-    assert(vq);
-    VuVirtqElement *elem;
     while (1) {
-        elem = vu_queue_pop(vu_dev, vq, sizeof(VuVirtqElement) +
-                                    sizeof(VuBlockReq));
-        if (elem) {
-            req_data = g_new0(struct req_data, 1);
-            req_data->server = server;
-            req_data->vq = vq;
-            req_data->elem = elem;
-            Coroutine *co = qemu_coroutine_create(vu_block_virtio_process_req,
-                                                  req_data);
-            aio_co_enter(server->ioc->ctx, co);
-        } else {
+        VuBlockReq *req;
+
+        req = vu_queue_pop(vu_dev, vq, sizeof(VuBlockReq));
+        if (!req) {
             break;
         }
+
+        req->server = server;
+        req->vq = vq;
+
+        Coroutine *co =
+            qemu_coroutine_create(vu_block_virtio_process_req, req);
+        qemu_coroutine_enter(co);
     }
 }
 
-- 
2.26.2

The device panic notifier callback is not used. Drop it.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200924151549.913737-7-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 util/vhost-user-server.h             | 3 ---
 block/export/vhost-user-blk-server.c | 3 +--
 util/vhost-user-server.c             | 6 ------
 3 files changed, 1 insertion(+), 11 deletions(-)

diff --git a/util/vhost-user-server.h b/util/vhost-user-server.h
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.h
+++ b/util/vhost-user-server.h
@@ -XXX,XX +XXX,XX @@ typedef struct VuFdWatch {
 } VuFdWatch;
 
 typedef struct VuServer VuServer;
-typedef void DevicePanicNotifierFn(VuServer *server);
 
 struct VuServer {
     QIONetListener *listener;
     AioContext *ctx;
-    DevicePanicNotifierFn *device_panic_notifier;
     int max_queues;
     const VuDevIface *vu_iface;
     VuDev vu_dev;
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
                              SocketAddress *unix_socket,
                              AioContext *ctx,
                              uint16_t max_queues,
-                             DevicePanicNotifierFn *device_panic_notifier,
                              const VuDevIface *vu_iface,
                              Error **errp);
 
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.c
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@ static void vhost_user_blk_server_start(VuBlockDev *vu_block_device,
     ctx = bdrv_get_aio_context(blk_bs(vu_block_device->backend));
 
     if (!vhost_user_server_start(&vu_block_device->vu_server, addr, ctx,
-                                 VHOST_USER_BLK_MAX_QUEUES,
-                                 NULL, &vu_block_iface,
+                                 VHOST_USER_BLK_MAX_QUEUES, &vu_block_iface,
                                  errp)) {
         goto error;
     }
diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@ static void panic_cb(VuDev *vu_dev, const char *buf)
         close_client(server);
     }
 
-    if (server->device_panic_notifier) {
-        server->device_panic_notifier(server);
-    }
-
     /*
      * Set the callback function for network listener so another
      * vhost-user client can connect to this server
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
                              SocketAddress *socket_addr,
                              AioContext *ctx,
                              uint16_t max_queues,
-                             DevicePanicNotifierFn *device_panic_notifier,
                              const VuDevIface *vu_iface,
                              Error **errp)
 {
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
         .vu_iface              = vu_iface,
         .max_queues            = max_queues,
         .ctx                   = ctx,
-        .device_panic_notifier = device_panic_notifier,
     };
 
     qio_net_listener_set_name(server->listener, "vhost-user-backend-listener");
-- 
2.26.2

fds[] is leaked when qio_channel_readv_full() fails.

Use vmsg->fds[] instead of keeping a local fds[] array. Then we can
reuse goto fail to clean up fds. vmsg->fd_num must be zeroed before the
loop to make this safe.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200924151549.913737-8-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 util/vhost-user-server.c | 50 ++++++++++++++++++----------------------
 1 file changed, 23 insertions(+), 27 deletions(-)

diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@ vu_message_read(VuDev *vu_dev, int conn_fd, VhostUserMsg *vmsg)
     };
     int rc, read_bytes = 0;
     Error *local_err = NULL;
-    /*
-     * Store fds/nfds returned from qio_channel_readv_full into
-     * temporary variables.
-     *
-     * VhostUserMsg is a packed structure, gcc will complain about passing
-     * pointer to a packed structure member if we pass &VhostUserMsg.fd_num
-     * and &VhostUserMsg.fds directly when calling qio_channel_readv_full,
-     * thus two temporary variables nfds and fds are used here.
-     */
-    size_t nfds = 0, nfds_t = 0;
     const size_t max_fds = G_N_ELEMENTS(vmsg->fds);
-    int *fds_t = NULL;
     VuServer *server = container_of(vu_dev, VuServer, vu_dev);
     QIOChannel *ioc = server->ioc;
 
+    vmsg->fd_num = 0;
     if (!ioc) {
         error_report_err(local_err);
         goto fail;
@@ -XXX,XX +XXX,XX @@ vu_message_read(VuDev *vu_dev, int conn_fd, VhostUserMsg *vmsg)
 
     assert(qemu_in_coroutine());
     do {
+        size_t nfds = 0;
+        int *fds = NULL;
+
         /*
          * qio_channel_readv_full may have short reads, keeping calling it
          * until getting VHOST_USER_HDR_SIZE or 0 bytes in total
          */
-        rc = qio_channel_readv_full(ioc, &iov, 1, &fds_t, &nfds_t, &local_err);
+        rc = qio_channel_readv_full(ioc, &iov, 1, &fds, &nfds, &local_err);
         if (rc < 0) {
             if (rc == QIO_CHANNEL_ERR_BLOCK) {
+                assert(local_err == NULL);
                 qio_channel_yield(ioc, G_IO_IN);
                 continue;
             } else {
                 error_report_err(local_err);
-                return false;
+                goto fail;
             }
         }
-        read_bytes += rc;
-        if (nfds_t > 0) {
-            if (nfds + nfds_t > max_fds) {
+
+        if (nfds > 0) {
+            if (vmsg->fd_num + nfds > max_fds) {
                 error_report("A maximum of %zu fds are allowed, "
                              "however got %lu fds now",
-                             max_fds, nfds + nfds_t);
+                             max_fds, vmsg->fd_num + nfds);
+                g_free(fds);
                 goto fail;
             }
-            memcpy(vmsg->fds + nfds, fds_t,
-                   nfds_t *sizeof(vmsg->fds[0]));
-            nfds += nfds_t;
-            g_free(fds_t);
+            memcpy(vmsg->fds + vmsg->fd_num, fds, nfds * sizeof(vmsg->fds[0]));
+            vmsg->fd_num += nfds;
+            g_free(fds);
         }
-        if (read_bytes == VHOST_USER_HDR_SIZE || rc == 0) {
-            break;
+
+        if (rc == 0) { /* socket closed */
+            goto fail;
         }
-        iov.iov_base = (char *)vmsg + read_bytes;
-        iov.iov_len = VHOST_USER_HDR_SIZE - read_bytes;
-    } while (true);
 
-    vmsg->fd_num = nfds;
+        iov.iov_base += rc;
+        iov.iov_len -= rc;
+        read_bytes += rc;
+    } while (read_bytes != VHOST_USER_HDR_SIZE);
+
     /* qio_channel_readv_full will make socket fds blocking, unblock them */
     vmsg_unblock_fds(vmsg);
     if (vmsg->size > sizeof(vmsg->payload)) {
-- 
2.26.2

The vu_client_trip() coroutine is leaked during AioContext switching. It
is also unsafe to destroy the vu_dev in panic_cb() since its callers
still access it in some cases.

Rework the lifecycle to solve these safety issues.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200924151549.913737-10-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 util/vhost-user-server.h             |  29 ++--
 block/export/vhost-user-blk-server.c |   9 +-
 util/vhost-user-server.c             | 245 +++++++++++++++------------
 3 files changed, 155 insertions(+), 128 deletions(-)

diff --git a/util/vhost-user-server.h b/util/vhost-user-server.h
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.h
+++ b/util/vhost-user-server.h
@@ -XXX,XX +XXX,XX @@
 #include "qapi/error.h"
 #include "standard-headers/linux/virtio_blk.h"
 
+/* A kick fd that we monitor on behalf of libvhost-user */
 typedef struct VuFdWatch {
     VuDev *vu_dev;
     int fd; /*kick fd*/
     void *pvt;
     vu_watch_cb cb;
-    bool processing;
     QTAILQ_ENTRY(VuFdWatch) next;
 } VuFdWatch;
 
-typedef struct VuServer VuServer;
-
-struct VuServer {
+/**
+ * VuServer:
+ * A vhost-user server instance with user-defined VuDevIface callbacks.
+ * Vhost-user device backends can be implemented using VuServer. VuDevIface
+ * callbacks and virtqueue kicks run in the given AioContext.
+ */
+typedef struct {
     QIONetListener *listener;
+    QEMUBH *restart_listener_bh;
     AioContext *ctx;
     int max_queues;
     const VuDevIface *vu_iface;
+
+    /* Protected by ctx lock */
     VuDev vu_dev;
     QIOChannel *ioc; /* The I/O channel with the client */
     QIOChannelSocket *sioc; /* The underlying data channel with the client */
-    /* IOChannel for fd provided via VHOST_USER_SET_SLAVE_REQ_FD */
-    QIOChannel *ioc_slave;
-    QIOChannelSocket *sioc_slave;
-    Coroutine *co_trip; /* coroutine for processing VhostUserMsg */
     QTAILQ_HEAD(, VuFdWatch) vu_fd_watches;
-    /* restart coroutine co_trip if AIOContext is changed */
-    bool aio_context_changed;
-    bool processing_msg;
-};
+
+    Coroutine *co_trip; /* coroutine for processing VhostUserMsg */
+} VuServer;
 
 bool vhost_user_server_start(VuServer *server,
                              SocketAddress *unix_socket,
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
 
 void vhost_user_server_stop(VuServer *server);
 
-void vhost_user_server_set_aio_context(VuServer *server, AioContext *ctx);
+void vhost_user_server_attach_aio_context(VuServer *server, AioContext *ctx);
+void vhost_user_server_detach_aio_context(VuServer *server);
 
 #endif /* VHOST_USER_SERVER_H */
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.c
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@ static const VuDevIface vu_block_iface = {
 static void blk_aio_attached(AioContext *ctx, void *opaque)
 {
     VuBlockDev *vub_dev = opaque;
-    aio_context_acquire(ctx);
-    vhost_user_server_set_aio_context(&vub_dev->vu_server, ctx);
-    aio_context_release(ctx);
+    vhost_user_server_attach_aio_context(&vub_dev->vu_server, ctx);
 }
 
 static void blk_aio_detach(void *opaque)
 {
     VuBlockDev *vub_dev = opaque;
-    AioContext *ctx = vub_dev->vu_server.ctx;
-    aio_context_acquire(ctx);
-    vhost_user_server_set_aio_context(&vub_dev->vu_server, NULL);
-    aio_context_release(ctx);
+    vhost_user_server_detach_aio_context(&vub_dev->vu_server);
 }
 
 static void
diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@
  */
 #include "qemu/osdep.h"
 #include "qemu/main-loop.h"
+#include "block/aio-wait.h"
 #include "vhost-user-server.h"
 
+/*
+ * Theory of operation:
+ *
+ * VuServer is started and stopped by vhost_user_server_start() and
+ * vhost_user_server_stop() from the main loop thread. Starting the server
+ * opens a vhost-user UNIX domain socket and listens for incoming connections.
+ * Only one connection is allowed at a time.
+ *
+ * The connection is handled by the vu_client_trip() coroutine in the
+ * VuServer->ctx AioContext. The coroutine consists of a vu_dispatch() loop
+ * where libvhost-user calls vu_message_read() to receive the next vhost-user
+ * protocol messages over the UNIX domain socket.
+ *
+ * When virtqueues are set up libvhost-user calls set_watch() to monitor kick
+ * fds. These fds are also handled in the VuServer->ctx AioContext.
+ *
+ * Both vu_client_trip() and kick fd monitoring can be stopped by shutting down
+ * the socket connection. Shutting down the socket connection causes
+ * vu_message_read() to fail since no more data can be received from the socket.
+ * After vu_dispatch() fails, vu_client_trip() calls vu_deinit() to stop
+ * libvhost-user before terminating the coroutine. vu_deinit() calls
+ * remove_watch() to stop monitoring kick fds and this stops virtqueue
+ * processing.
+ *
+ * When vu_client_trip() has finished cleaning up it schedules a BH in the main
+ * loop thread to accept the next client connection.
+ *
+ * When libvhost-user detects an error it calls panic_cb() and sets the
+ * dev->broken flag. Both vu_client_trip() and kick fd processing stop when
+ * the dev->broken flag is set.
+ *
+ * It is possible to switch AioContexts using
+ * vhost_user_server_detach_aio_context() and
+ * vhost_user_server_attach_aio_context(). They stop monitoring fds in the old
+ * AioContext and resume monitoring in the new AioContext. The vu_client_trip()
+ * coroutine remains in a yielded state during the switch. This is made
+ * possible by QIOChannel's support for spurious coroutine re-entry in
+ * qio_channel_yield(). The coroutine will restart I/O when re-entered from the
+ * new AioContext.
+ */
+
 static void vmsg_close_fds(VhostUserMsg *vmsg)
 {
     int i;
@@ -XXX,XX +XXX,XX @@ static void vmsg_unblock_fds(VhostUserMsg *vmsg)
     }
 }
 
-static void vu_accept(QIONetListener *listener, QIOChannelSocket *sioc,
-                      gpointer opaque);
-
-static void close_client(VuServer *server)
-{
-    /*
-     * Before closing the client
-     *
-     * 1. Let vu_client_trip stop processing new vhost-user msg
-     *
-     * 2. remove kick_handler
-     *
-     * 3. wait for the kick handler to be finished
-     *
-     * 4. wait for the current vhost-user msg to be finished processing
-     */
-
-    QIOChannelSocket *sioc = server->sioc;
-    /* When this is set vu_client_trip will stop new processing vhost-user message */
-    server->sioc = NULL;
-
-    while (server->processing_msg) {
-        if (server->ioc->read_coroutine) {
-            server->ioc->read_coroutine = NULL;
-            qio_channel_set_aio_fd_handler(server->ioc, server->ioc->ctx, NULL,
-                                           NULL, server->ioc);
-            server->processing_msg = false;
-        }
-    }
-
-    vu_deinit(&server->vu_dev);
-
-    /* vu_deinit() should have called remove_watch() */
-    assert(QTAILQ_EMPTY(&server->vu_fd_watches));
-
-    object_unref(OBJECT(sioc));
-    object_unref(OBJECT(server->ioc));
-}
-
 static void panic_cb(VuDev *vu_dev, const char *buf)
 {
-    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
-
-    /* avoid while loop in close_client */
-    server->processing_msg = false;
-
-    if (buf) {
-        error_report("vu_panic: %s", buf);
-    }
-
-    if (server->sioc) {
-        close_client(server);
-    }
-
-    /*
-     * Set the callback function for network listener so another
-     * vhost-user client can connect to this server
-     */
-    qio_net_listener_set_client_func(server->listener,
-                                     vu_accept,
-                                     server,
-                                     NULL);
+    error_report("vu_panic: %s", buf);
 }
 
 static bool coroutine_fn
@@ -XXX,XX +XXX,XX @@ fail:
     return false;
 }
 
-
-static void vu_client_start(VuServer *server);
 static coroutine_fn void vu_client_trip(void *opaque)
 {
     VuServer *server = opaque;
+    VuDev *vu_dev = &server->vu_dev;
 
-    while (!server->aio_context_changed && server->sioc) {
-        server->processing_msg = true;
-        vu_dispatch(&server->vu_dev);
-        server->processing_msg = false;
+    while (!vu_dev->broken && vu_dispatch(vu_dev)) {
+        /* Keep running */
     }
 
-    if (server->aio_context_changed && server->sioc) {
-        server->aio_context_changed = false;
-        vu_client_start(server);
-    }
-}
+    vu_deinit(vu_dev);
+
+    /* vu_deinit() should have called remove_watch() */
+    assert(QTAILQ_EMPTY(&server->vu_fd_watches));
+
+    object_unref(OBJECT(server->sioc));
+    server->sioc = NULL;
 
-static void vu_client_start(VuServer *server)
-{
-    server->co_trip = qemu_coroutine_create(vu_client_trip, server);
-    aio_co_enter(server->ctx, server->co_trip);
+    object_unref(OBJECT(server->ioc));
+    server->ioc = NULL;
+
+    server->co_trip = NULL;
+    if (server->restart_listener_bh) {
+        qemu_bh_schedule(server->restart_listener_bh);
+    }
+    aio_wait_kick();
 }
 
 /*
@@ -XXX,XX +XXX,XX @@ static void vu_client_start(VuServer *server)
 static void kick_handler(void *opaque)
 {
     VuFdWatch *vu_fd_watch = opaque;
-    vu_fd_watch->processing = true;
-    vu_fd_watch->cb(vu_fd_watch->vu_dev, 0, vu_fd_watch->pvt);
-    vu_fd_watch->processing = false;
+    VuDev *vu_dev = vu_fd_watch->vu_dev;
+
+    vu_fd_watch->cb(vu_dev, 0, vu_fd_watch->pvt);
+
+    /* Stop vu_client_trip() if an error occurred in vu_fd_watch->cb() */
+    if (vu_dev->broken) {
+        VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+
+        qio_channel_shutdown(server->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
+    }
 }
 
-
 static VuFdWatch *find_vu_fd_watch(VuServer *server, int fd)
 {
 
@@ -XXX,XX +XXX,XX @@ static void vu_accept(QIONetListener *listener, QIOChannelSocket *sioc,
     qio_channel_set_name(QIO_CHANNEL(sioc), "vhost-user client");
     server->ioc = QIO_CHANNEL(sioc);
     object_ref(OBJECT(server->ioc));
-    qio_channel_attach_aio_context(server->ioc, server->ctx);
+
+    /* TODO vu_message_write() spins if non-blocking! */
     qio_channel_set_blocking(server->ioc, false, NULL);
-    vu_client_start(server);
+
+    server->co_trip = qemu_coroutine_create(vu_client_trip, server);
+
+    aio_context_acquire(server->ctx);
+    vhost_user_server_attach_aio_context(server, server->ctx);
+    aio_context_release(server->ctx);
 }
 
-
 void vhost_user_server_stop(VuServer *server)
 {
+    aio_context_acquire(server->ctx);
+
+    qemu_bh_delete(server->restart_listener_bh);
+    server->restart_listener_bh = NULL;
+
     if (server->sioc) {
-        close_client(server);
+        VuFdWatch *vu_fd_watch;
+
+        QTAILQ_FOREACH(vu_fd_watch, &server->vu_fd_watches, next) {
+            aio_set_fd_handler(server->ctx, vu_fd_watch->fd, true,
+                               NULL, NULL, NULL, vu_fd_watch);
+        }
+
+        qio_channel_shutdown(server->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
+
+        AIO_WAIT_WHILE(server->ctx, server->co_trip);
     }
 
+    aio_context_release(server->ctx);
+
     if (server->listener) {
         qio_net_listener_disconnect(server->listener);
         object_unref(OBJECT(server->listener));
     }
+}
+
+/*
+ * Allow the next client to connect to the server. Called from a BH in the main
+ * loop.
+ */
+static void restart_listener_bh(void *opaque)
+{
+    VuServer *server = opaque;
 
+    qio_net_listener_set_client_func(server->listener, vu_accept, server,
+                                     NULL);
 }
 
-void vhost_user_server_set_aio_context(VuServer *server, AioContext *ctx)
+/* Called with ctx acquired */
+void vhost_user_server_attach_aio_context(VuServer *server, AioContext *ctx)
 {
-    VuFdWatch *vu_fd_watch, *next;
-    void *opaque = NULL;
-    IOHandler *io_read = NULL;
-    bool attach;
+    VuFdWatch *vu_fd_watch;
 
-    server->ctx = ctx ? ctx : qemu_get_aio_context();
+    server->ctx = ctx;
 
     if (!server->sioc) {
-        /* not yet serving any client*/
         return;
     }
 
-    if (ctx) {
-        qio_channel_attach_aio_context(server->ioc, ctx);
-        server->aio_context_changed = true;
-        io_read = kick_handler;
-        attach = true;
-    } else {
+    qio_channel_attach_aio_context(server->ioc, ctx);
+
+    QTAILQ_FOREACH(vu_fd_watch, &server->vu_fd_watches, next) {
+        aio_set_fd_handler(ctx, vu_fd_watch->fd, true, kick_handler, NULL,
+                           NULL, vu_fd_watch);
+    }
+
+    aio_co_schedule(ctx, server->co_trip);
+}
+
+/* Called with server->ctx acquired */
+void vhost_user_server_detach_aio_context(VuServer *server)
+{
+    if (server->sioc) {
+        VuFdWatch *vu_fd_watch;
+
+        QTAILQ_FOREACH(vu_fd_watch, &server->vu_fd_watches, next) {
+            aio_set_fd_handler(server->ctx, vu_fd_watch->fd, true,
+                               NULL, NULL, NULL, vu_fd_watch);
+        }
+
         qio_channel_detach_aio_context(server->ioc);
-        /* server->ioc->ctx keeps the old AioConext */
-        ctx = server->ioc->ctx;
-        attach = false;
     }
 
-    QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
-        if (vu_fd_watch->cb) {
-            opaque = attach ? vu_fd_watch : NULL;
-            aio_set_fd_handler(ctx, vu_fd_watch->fd, true,
-                               io_read, NULL, NULL,
-                               opaque);
-        }
-    }
+    server->ctx = NULL;
 }
 
-
 bool vhost_user_server_start(VuServer *server,
                              SocketAddress *socket_addr,
                              AioContext *ctx,
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
                              const VuDevIface *vu_iface,
                              Error **errp)
 {
+    QEMUBH *bh;
     QIONetListener *listener = qio_net_listener_new();
     if (qio_net_listener_open_sync(listener, socket_addr, 1,
                                    errp) < 0) {
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
         return false;
     }
 
+    bh = qemu_bh_new(restart_listener_bh, server);
+
     /* zero out unspecified fields */
     *server = (VuServer) {
         .listener              = listener,
+        .restart_listener_bh   = bh,
         .vu_iface              = vu_iface,
         .max_queues            = max_queues,
         .ctx                   = ctx,
-- 
2.26.2

Propagate the flush return value since errors are possible.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200924151549.913737-11-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/export/vhost-user-blk-server.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

Use the new QAPI block exports API instead of defining our own QOM
objects.

This is a large change because the lifecycle of VuBlockDev needs to
follow BlockExportDriver. QOM properties are replaced by QAPI options
objects.

VuBlockDev is renamed VuBlkExport and contains a BlockExport field.
Several fields can be dropped since BlockExport already has equivalents.

The file names and meson build integration will be adjusted in a future
patch. libvhost-user should probably be built as a static library that
is linked into QEMU instead of as a .c file that results in duplicate
compilation.

The new command-line syntax is:

$ qemu-storage-daemon \
      --blockdev file,node-name=drive0,filename=test.img \
      --export vhost-user-blk,node-name=drive0,id=export0,unix-socket=/tmp/vhost-user-blk.sock

Note that unix-socket is optional because we may wish to accept chardevs
too in the future.

Markus noted that supported address families are not explicit in the
QAPI schema. It is unlikely that support for more address families will
be added since file descriptor passing is required and few address
families support it. If a new address family needs to be added, then the
QAPI 'features' syntax can be used to advertize them.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20200924151549.913737-12-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 qapi/block-export.json               |  21 +-
 block/export/vhost-user-blk-server.h |  23 +-
 block/export/export.c                |   6 +
 block/export/vhost-user-blk-server.c | 452 +++++++--------------------
 tests/qtest/vhost-user-blk-test.c    |   2 +-
 util/vhost-user-server.c             |  10 +-
 block/export/meson.build             |   1 +
 block/meson.build                    |   1 -
 8 files changed, 157 insertions(+), 359 deletions(-)

diff --git a/qapi/block-export.json b/qapi/block-export.json
index XXXXXXX..XXXXXXX 100644
--- a/qapi/block-export.json
+++ b/qapi/block-export.json
@@ -XXX,XX +XXX,XX @@
   'data': { '*name': 'str', '*description': 'str',
             '*bitmap': 'str' } }
 
+##
+# @BlockExportOptionsVhostUserBlk:
+#
+# A vhost-user-blk block export.
+#
+# @addr: The vhost-user socket on which to listen. Both 'unix' and 'fd'
+#        SocketAddress types are supported. Passed fds must be UNIX domain
+#        sockets.
+# @logical-block-size: Logical block size in bytes. Defaults to 512 bytes.
+#
+# Since: 5.2
+##
+{ 'struct': 'BlockExportOptionsVhostUserBlk',
+  'data': { 'addr': 'SocketAddress', '*logical-block-size': 'size' } }
+
 ##
 # @NbdServerAddOptions:
 #
@@ -XXX,XX +XXX,XX @@
 # An enumeration of block export types
 #
 # @nbd: NBD export
+# @vhost-user-blk: vhost-user-blk export (since 5.2)
 #
 # Since: 4.2
 ##
 { 'enum': 'BlockExportType',
-  'data': [ 'nbd' ] }
+  'data': [ 'nbd', 'vhost-user-blk' ] }
 
 ##
 # @BlockExportOptions:
@@ -XXX,XX +XXX,XX @@
             '*writethrough': 'bool' },
   'discriminator': 'type',
   'data': {
-      'nbd': 'BlockExportOptionsNbd'
+      'nbd': 'BlockExportOptionsNbd',
+      'vhost-user-blk': 'BlockExportOptionsVhostUserBlk'
    } }
 
 ##
diff --git a/block/export/vhost-user-blk-server.h b/block/export/vhost-user-blk-server.h
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.h
+++ b/block/export/vhost-user-blk-server.h
@@ -XXX,XX +XXX,XX @@
 
 #ifndef VHOST_USER_BLK_SERVER_H
 #define VHOST_USER_BLK_SERVER_H
-#include "util/vhost-user-server.h"
 
-typedef struct VuBlockDev VuBlockDev;
-#define TYPE_VHOST_USER_BLK_SERVER "vhost-user-blk-server"
-#define VHOST_USER_BLK_SERVER(obj) \
-   OBJECT_CHECK(VuBlockDev, obj, TYPE_VHOST_USER_BLK_SERVER)
+#include "block/export.h"
 
-/* vhost user block device */
-struct VuBlockDev {
-    Object parent_obj;
-    char *node_name;
-    SocketAddress *addr;
-    AioContext *ctx;
-    VuServer vu_server;
-    bool running;
-    uint32_t blk_size;
-    BlockBackend *backend;
-    QIOChannelSocket *sioc;
-    QTAILQ_ENTRY(VuBlockDev) next;
-    struct virtio_blk_config blkcfg;
-    bool writable;
-};
+/* For block/export/export.c */
+extern const BlockExportDriver blk_exp_vhost_user_blk;
 
 #endif /* VHOST_USER_BLK_SERVER_H */
diff --git a/block/export/export.c b/block/export/export.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/export.c
+++ b/block/export/export.c
@@ -XXX,XX +XXX,XX @@
 #include "sysemu/block-backend.h"
 #include "block/export.h"
 #include "block/nbd.h"
+#if CONFIG_LINUX
+#include "block/export/vhost-user-blk-server.h"
+#endif
 #include "qapi/error.h"
 #include "qapi/qapi-commands-block-export.h"
 #include "qapi/qapi-events-block-export.h"
@@ -XXX,XX +XXX,XX @@
 
 static const BlockExportDriver *blk_exp_drivers[] = {
     &blk_exp_nbd,
+#if CONFIG_LINUX
+    &blk_exp_vhost_user_blk,
+#endif
 };
 
 /* Only accessed from the main thread */
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.c
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@
  */
 #include "qemu/osdep.h"
 #include "block/block.h"
+#include "contrib/libvhost-user/libvhost-user.h"
+#include "standard-headers/linux/virtio_blk.h"
+#include "util/vhost-user-server.h"
 #include "vhost-user-blk-server.h"
 #include "qapi/error.h"
 #include "qom/object_interfaces.h"
@@ -XXX,XX +XXX,XX @@ struct virtio_blk_inhdr {
     unsigned char status;
 };
 
-typedef struct VuBlockReq {
+typedef struct VuBlkReq {
     VuVirtqElement elem;
     int64_t sector_num;
     size_t size;
@@ -XXX,XX +XXX,XX @@ typedef struct VuBlockReq {
     struct virtio_blk_outhdr out;
     VuServer *server;
     struct VuVirtq *vq;
-} VuBlockReq;
+} VuBlkReq;
 
-static void vu_block_req_complete(VuBlockReq *req)
+/* vhost user block device */
+typedef struct {
+    BlockExport export;
+    VuServer vu_server;
+    uint32_t blk_size;
+    QIOChannelSocket *sioc;
+    struct virtio_blk_config blkcfg;
+    bool writable;
+} VuBlkExport;
+
+static void vu_blk_req_complete(VuBlkReq *req)
 {
     VuDev *vu_dev = &req->server->vu_dev;
 
@@ -XXX,XX +XXX,XX @@ static void vu_block_req_complete(VuBlockReq *req)
     free(req);
 }
 
-static VuBlockDev *get_vu_block_device_by_server(VuServer *server)
-{
-    return container_of(server, VuBlockDev, vu_server);
-}
-
 static int coroutine_fn
-vu_block_discard_write_zeroes(VuBlockReq *req, struct iovec *iov,
-                              uint32_t iovcnt, uint32_t type)
+vu_blk_discard_write_zeroes(BlockBackend *blk, struct iovec *iov,
+                            uint32_t iovcnt, uint32_t type)
 {
     struct virtio_blk_discard_write_zeroes desc;
     ssize_t size = iov_to_buf(iov, iovcnt, 0, &desc, sizeof(desc));
@@ -XXX,XX +XXX,XX @@ vu_block_discard_write_zeroes(VuBlockReq *req, struct iovec *iov,
         return -EINVAL;
     }
 
-    VuBlockDev *vdev_blk = get_vu_block_device_by_server(req->server);
     uint64_t range[2] = { le64_to_cpu(desc.sector) << 9,
                           le32_to_cpu(desc.num_sectors) << 9 };
     if (type == VIRTIO_BLK_T_DISCARD) {
-        if (blk_co_pdiscard(vdev_blk->backend, range[0], range[1]) == 0) {
+        if (blk_co_pdiscard(blk, range[0], range[1]) == 0) {
             return 0;
         }
     } else if (type == VIRTIO_BLK_T_WRITE_ZEROES) {
-        if (blk_co_pwrite_zeroes(vdev_blk->backend,
-                                 range[0], range[1], 0) == 0) {
+        if (blk_co_pwrite_zeroes(blk, range[0], range[1], 0) == 0) {
             return 0;
         }
     }
@@ -XXX,XX +XXX,XX @@ vu_block_discard_write_zeroes(VuBlockReq *req, struct iovec *iov,
     return -EINVAL;
 }
 
-static int coroutine_fn vu_block_flush(VuBlockReq *req)
+static void coroutine_fn vu_blk_virtio_process_req(void *opaque)
 {
-    VuBlockDev *vdev_blk = get_vu_block_device_by_server(req->server);
-    BlockBackend *backend = vdev_blk->backend;
-    return blk_co_flush(backend);
-}
-
-static void coroutine_fn vu_block_virtio_process_req(void *opaque)
-{
-    VuBlockReq *req = opaque;
+    VuBlkReq *req = opaque;
     VuServer *server = req->server;
     VuVirtqElement *elem = &req->elem;
     uint32_t type;
 
-    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
-    BlockBackend *backend = vdev_blk->backend;
+    VuBlkExport *vexp = container_of(server, VuBlkExport, vu_server);
+    BlockBackend *blk = vexp->export.blk;
 
     struct iovec *in_iov = elem->in_sg;
     struct iovec *out_iov = elem->out_sg;
@@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
         bool is_write = type & VIRTIO_BLK_T_OUT;
         req->sector_num = le64_to_cpu(req->out.sector);
 
-        int64_t offset = req->sector_num * vdev_blk->blk_size;
+        if (is_write && !vexp->writable) {
+            req->in->status = VIRTIO_BLK_S_IOERR;
+            break;
+        }
+
+        int64_t offset = req->sector_num * vexp->blk_size;
         QEMUIOVector qiov;
         if (is_write) {
             qemu_iovec_init_external(&qiov, out_iov, out_num);
-            ret = blk_co_pwritev(backend, offset, qiov.size,
-                                 &qiov, 0);
+            ret = blk_co_pwritev(blk, offset, qiov.size, &qiov, 0);
         } else {
             qemu_iovec_init_external(&qiov, in_iov, in_num);
-            ret = blk_co_preadv(backend, offset, qiov.size,
-                                &qiov, 0);
+            ret = blk_co_preadv(blk, offset, qiov.size, &qiov, 0);
         }
         if (ret >= 0) {
             req->in->status = VIRTIO_BLK_S_OK;
@@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
         break;
     }
     case VIRTIO_BLK_T_FLUSH:
-        if (vu_block_flush(req) == 0) {
+        if (blk_co_flush(blk) == 0) {
             req->in->status = VIRTIO_BLK_S_OK;
         } else {
             req->in->status = VIRTIO_BLK_S_IOERR;
@@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
     case VIRTIO_BLK_T_DISCARD:
     case VIRTIO_BLK_T_WRITE_ZEROES: {
         int rc;
-        rc = vu_block_discard_write_zeroes(req, &elem->out_sg[1],
-                                           out_num, type);
+
+        if (!vexp->writable) {
+            req->in->status = VIRTIO_BLK_S_IOERR;
+            break;
+        }
+
+        rc = vu_blk_discard_write_zeroes(blk, &elem->out_sg[1], out_num, type);
         if (rc == 0) {
             req->in->status = VIRTIO_BLK_S_OK;
         } else {
@@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
         break;
     }
 
-    vu_block_req_complete(req);
+    vu_blk_req_complete(req);
     return;
 
 err:
-    free(elem);
+    free(req);
 }
 
-static void vu_block_process_vq(VuDev *vu_dev, int idx)
+static void vu_blk_process_vq(VuDev *vu_dev, int idx)
 {
     VuServer *server = container_of(vu_dev, VuServer, vu_dev);
     VuVirtq *vq = vu_get_queue(vu_dev, idx);
 
     while (1) {
-        VuBlockReq *req;
+        VuBlkReq *req;
 
-        req = vu_queue_pop(vu_dev, vq, sizeof(VuBlockReq));
+        req = vu_queue_pop(vu_dev, vq, sizeof(VuBlkReq));
         if (!req) {
             break;
         }
@@ -XXX,XX +XXX,XX @@ static void vu_block_process_vq(VuDev *vu_dev, int idx)
         req->vq = vq;
 
         Coroutine *co =
-            qemu_coroutine_create(vu_block_virtio_process_req, req);
+            qemu_coroutine_create(vu_blk_virtio_process_req, req);
         qemu_coroutine_enter(co);
     }
 }
 
-static void vu_block_queue_set_started(VuDev *vu_dev, int idx, bool started)
+static void vu_blk_queue_set_started(VuDev *vu_dev, int idx, bool started)
 {
     VuVirtq *vq;
 
     assert(vu_dev);
 
     vq = vu_get_queue(vu_dev, idx);
-    vu_set_queue_handler(vu_dev, vq, started ? vu_block_process_vq : NULL);
+    vu_set_queue_handler(vu_dev, vq, started ? vu_blk_process_vq : NULL);
 }
 
-static uint64_t vu_block_get_features(VuDev *dev)
+static uint64_t vu_blk_get_features(VuDev *dev)
 {
     uint64_t features;
     VuServer *server = container_of(dev, VuServer, vu_dev);
-    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+    VuBlkExport *vexp = container_of(server, VuBlkExport, vu_server);
     features = 1ull << VIRTIO_BLK_F_SIZE_MAX |
                1ull << VIRTIO_BLK_F_SEG_MAX |
                1ull << VIRTIO_BLK_F_TOPOLOGY |
@@ -XXX,XX +XXX,XX @@ static uint64_t vu_block_get_features(VuDev *dev)
                1ull << VIRTIO_RING_F_EVENT_IDX |
                1ull << VHOST_USER_F_PROTOCOL_FEATURES;
 
-    if (!vdev_blk->writable) {
+    if (!vexp->writable) {
         features |= 1ull << VIRTIO_BLK_F_RO;
     }
 
     return features;
 }
 
-static uint64_t vu_block_get_protocol_features(VuDev *dev)
+static uint64_t vu_blk_get_protocol_features(VuDev *dev)
 {
     return 1ull << VHOST_USER_PROTOCOL_F_CONFIG |
            1ull << VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD;
 }
 
 static int
-vu_block_get_config(VuDev *vu_dev, uint8_t *config, uint32_t len)
+vu_blk_get_config(VuDev *vu_dev, uint8_t *config, uint32_t len)
 {
+    /* TODO blkcfg must be little-endian for VIRTIO 1.0 */
     VuServer *server = container_of(vu_dev, VuServer, vu_dev);
-    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
-    memcpy(config, &vdev_blk->blkcfg, len);
-
+    VuBlkExport *vexp = container_of(server, VuBlkExport, vu_server);
+    memcpy(config, &vexp->blkcfg, len);
     return 0;
 }
 
 static int
-vu_block_set_config(VuDev *vu_dev, const uint8_t *data,
+vu_blk_set_config(VuDev *vu_dev, const uint8_t *data,
                     uint32_t offset, uint32_t size, uint32_t flags)
 {
     VuServer *server = container_of(vu_dev, VuServer, vu_dev);
-    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+    VuBlkExport *vexp = container_of(server, VuBlkExport, vu_server);
     uint8_t wce;
 
     /* don't support live migration */
@@ -XXX,XX +XXX,XX @@ vu_block_set_config(VuDev *vu_dev, const uint8_t *data,
     }
 
     wce = *data;
-    vdev_blk->blkcfg.wce = wce;
-    blk_set_enable_write_cache(vdev_blk->backend, wce);
+    vexp->blkcfg.wce = wce;
+    blk_set_enable_write_cache(vexp->export.blk, wce);
     return 0;
 }
 
@@ -XXX,XX +XXX,XX @@ vu_block_set_config(VuDev *vu_dev, const uint8_t *data,
  * of vu_process_message.
  *
  */
-static int vu_block_process_msg(VuDev *dev, VhostUserMsg *vmsg, int *do_reply)
+static int vu_blk_process_msg(VuDev *dev, VhostUserMsg *vmsg, int *do_reply)
 {
     if (vmsg->request == VHOST_USER_NONE) {
         dev->panic(dev, "disconnect");
@@ -XXX,XX +XXX,XX @@ static int vu_block_process_msg(VuDev *dev, VhostUserMsg *vmsg, int *do_reply)
     return false;
 }
 
-static const VuDevIface vu_block_iface = {
-    .get_features          = vu_block_get_features,
-    .queue_set_started     = vu_block_queue_set_started,
-    .get_protocol_features = vu_block_get_protocol_features,
-    .get_config            = vu_block_get_config,
-    .set_config            = vu_block_set_config,
-    .process_msg           = vu_block_process_msg,
+static const VuDevIface vu_blk_iface = {
+    .get_features          = vu_blk_get_features,
+    .queue_set_started     = vu_blk_queue_set_started,
+    .get_protocol_features = vu_blk_get_protocol_features,
+    .get_config            = vu_blk_get_config,
+    .set_config            = vu_blk_set_config,
+    .process_msg           = vu_blk_process_msg,
 };
 
 static void blk_aio_attached(AioContext *ctx, void *opaque)
 {
-    VuBlockDev *vub_dev = opaque;
-    vhost_user_server_attach_aio_context(&vub_dev->vu_server, ctx);
+    VuBlkExport *vexp = opaque;
+    vhost_user_server_attach_aio_context(&vexp->vu_server, ctx);
 }
 
 static void blk_aio_detach(void *opaque)
 {
-    VuBlockDev *vub_dev = opaque;
-    vhost_user_server_detach_aio_context(&vub_dev->vu_server);
+    VuBlkExport *vexp = opaque;
+    vhost_user_server_detach_aio_context(&vexp->vu_server);
 }
 
 static void
-vu_block_initialize_config(BlockDriverState *bs,
+vu_blk_initialize_config(BlockDriverState *bs,
                            struct virtio_blk_config *config, uint32_t blk_size)
 {
     config->capacity = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
@@ -XXX,XX +XXX,XX @@ vu_block_initialize_config(BlockDriverState *bs,
     config->max_write_zeroes_seg = 1;
 }
 
-static VuBlockDev *vu_block_init(VuBlockDev *vu_block_device, Error **errp)
+static void vu_blk_exp_request_shutdown(BlockExport *exp)
 {
+    VuBlkExport *vexp = container_of(exp, VuBlkExport, export);
 
-    BlockBackend *blk;
-    Error *local_error = NULL;
-    const char *node_name = vu_block_device->node_name;
-    bool writable = vu_block_device->writable;
-    uint64_t perm = BLK_PERM_CONSISTENT_READ;
-    int ret;
-
-    AioContext *ctx;
-
-    BlockDriverState *bs = bdrv_lookup_bs(node_name, node_name, &local_error);
-
-    if (!bs) {
-        error_propagate(errp, local_error);
-        return NULL;
-    }
-
-    if (bdrv_is_read_only(bs)) {
-        writable = false;
-    }
-
-    if (writable) {
-        perm |= BLK_PERM_WRITE;
-    }
-
-    ctx = bdrv_get_aio_context(bs);
-    aio_context_acquire(ctx);
-    bdrv_invalidate_cache(bs, NULL);
-    aio_context_release(ctx);
-
-    /*
-     * Don't allow resize while the vhost user server is running,
-     * otherwise we don't care what happens with the node.
-     */
-    blk = blk_new(bdrv_get_aio_context(bs), perm,
-                  BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED |
-                  BLK_PERM_WRITE | BLK_PERM_GRAPH_MOD);
-    ret = blk_insert_bs(blk, bs, errp);
-
-    if (ret < 0) {
-        goto fail;
-    }
-
-    blk_set_enable_write_cache(blk, false);
-
-    blk_set_allow_aio_context_change(blk, true);
-
-    vu_block_device->blkcfg.wce = 0;
-    vu_block_device->backend = blk;
-    if (!vu_block_device->blk_size) {
-        vu_block_device->blk_size = BDRV_SECTOR_SIZE;
-    }
-    vu_block_device->blkcfg.blk_size = vu_block_device->blk_size;
-    blk_set_guest_block_size(blk, vu_block_device->blk_size);
-    vu_block_initialize_config(bs, &vu_block_device->blkcfg,
-                                   vu_block_device->blk_size);
-    return vu_block_device;
-
-fail:
-    blk_unref(blk);
-    return NULL;
-}
-
-static void vu_block_deinit(VuBlockDev *vu_block_device)
-{
-    if (vu_block_device->backend) {
-        blk_remove_aio_context_notifier(vu_block_device->backend, blk_aio_attached,
-                                        blk_aio_detach, vu_block_device);
-    }
-
-    blk_unref(vu_block_device->backend);
-}
-
-static void vhost_user_blk_server_stop(VuBlockDev *vu_block_device)
-{
-    vhost_user_server_stop(&vu_block_device->vu_server);
-    vu_block_deinit(vu_block_device);
-}
-
-static void vhost_user_blk_server_start(VuBlockDev *vu_block_device,
-                                        Error **errp)
-{
-    AioContext *ctx;
-    SocketAddress *addr = vu_block_device->addr;
-
-    if (!vu_block_init(vu_block_device, errp)) {
-        return;
-    }
-
-    ctx = bdrv_get_aio_context(blk_bs(vu_block_device->backend));
-
-    if (!vhost_user_server_start(&vu_block_device->vu_server, addr, ctx,
-                                 VHOST_USER_BLK_MAX_QUEUES, &vu_block_iface,
-                                 errp)) {
-        goto error;
-    }
-
-    blk_add_aio_context_notifier(vu_block_device->backend, blk_aio_attached,
-                                 blk_aio_detach, vu_block_device);
-    vu_block_device->running = true;
-    return;
-
- error:
-    vu_block_deinit(vu_block_device);
-}
-
-static bool vu_prop_modifiable(VuBlockDev *vus, Error **errp)
-{
-    if (vus->running) {
-            error_setg(errp, "The property can't be modified "
-                       "while the server is running");
-            return false;
-    }
-    return true;
-}
-
-static void vu_set_node_name(Object *obj, const char *value, Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-
-    if (!vu_prop_modifiable(vus, errp)) {
-        return;
-    }
-
-    if (vus->node_name) {
-        g_free(vus->node_name);
-    }
-
-    vus->node_name = g_strdup(value);
-}
-
-static char *vu_get_node_name(Object *obj, Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-    return g_strdup(vus->node_name);
-}
-
-static void free_socket_addr(SocketAddress *addr)
-{
-        g_free(addr->u.q_unix.path);
-        g_free(addr);
-}
-
-static void vu_set_unix_socket(Object *obj, const char *value,
-                               Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-
-    if (!vu_prop_modifiable(vus, errp)) {
-        return;
-    }
-
-    if (vus->addr) {
-        free_socket_addr(vus->addr);
-    }
-
-    SocketAddress *addr = g_new0(SocketAddress, 1);
-    addr->type = SOCKET_ADDRESS_TYPE_UNIX;
-    addr->u.q_unix.path = g_strdup(value);
-    vus->addr = addr;
+    vhost_user_server_stop(&vexp->vu_server);
 }
 
-static char *vu_get_unix_socket(Object *obj, Error **errp)
+static int vu_blk_exp_create(BlockExport *exp, BlockExportOptions *opts,
+                             Error **errp)
 {
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-    return g_strdup(vus->addr->u.q_unix.path);
-}
-
-static bool vu_get_block_writable(Object *obj, Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-    return vus->writable;
-}
-
-static void vu_set_block_writable(Object *obj, bool value, Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-
-    if (!vu_prop_modifiable(vus, errp)) {
-            return;
-    }
-
-    vus->writable = value;
-}
-
-static void vu_get_blk_size(Object *obj, Visitor *v, const char *name,
-                            void *opaque, Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-    uint32_t value = vus->blk_size;
-
-    visit_type_uint32(v, name, &value, errp);
-}
-
-static void vu_set_blk_size(Object *obj, Visitor *v, const char *name,
-                            void *opaque, Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-
+    VuBlkExport *vexp = container_of(exp, VuBlkExport, export);
+    BlockExportOptionsVhostUserBlk *vu_opts = &opts->u.vhost_user_blk;
     Error *local_err = NULL;
-    uint32_t value;
+    uint64_t logical_block_size;
 
-    if (!vu_prop_modifiable(vus, errp)) {
-            return;
-    }
+    vexp->writable = opts->writable;
+    vexp->blkcfg.wce = 0;
 
-    visit_type_uint32(v, name, &value, &local_err);
-    if (local_err) {
-        goto out;
+    if (vu_opts->has_logical_block_size) {
+        logical_block_size = vu_opts->logical_block_size;
+    } else {
+        logical_block_size = BDRV_SECTOR_SIZE;
     }
-
-    check_block_size(object_get_typename(obj), name, value, &local_err);
+    check_block_size(exp->id, "logical-block-size", logical_block_size,
+                     &local_err);
     if (local_err) {
-        goto out;
+        error_propagate(errp, local_err);
+        return -EINVAL;
+    }
+    vexp->blk_size = logical_block_size;
+    blk_set_guest_block_size(exp->blk, logical_block_size);
+    vu_blk_initialize_config(blk_bs(exp->blk), &vexp->blkcfg,
+                               logical_block_size);
+
+    blk_set_allow_aio_context_change(exp->blk, true);
+    blk_add_aio_context_notifier(exp->blk, blk_aio_attached, blk_aio_detach,
+                                 vexp);
+
+    if (!vhost_user_server_start(&vexp->vu_server, vu_opts->addr, exp->ctx,
+                                 VHOST_USER_BLK_MAX_QUEUES, &vu_blk_iface,
+                                 errp)) {
+        blk_remove_aio_context_notifier(exp->blk, blk_aio_attached,
+                                        blk_aio_detach, vexp);
+        return -EADDRNOTAVAIL;
     }
 
-    vus->blk_size = value;
-
-out:
-    error_propagate(errp, local_err);
-}
-
-static void vhost_user_blk_server_instance_finalize(Object *obj)
-{
-    VuBlockDev *vub = VHOST_USER_BLK_SERVER(obj);
-
-    vhost_user_blk_server_stop(vub);
-
-    /*
-     * Unlike object_property_add_str, object_class_property_add_str
-     * doesn't have a release method. Thus manual memory freeing is
-     * needed.
-     */
-    free_socket_addr(vub->addr);
-    g_free(vub->node_name);
-}
-
-static void vhost_user_blk_server_complete(UserCreatable *obj, Error **errp)
-{
-    VuBlockDev *vub = VHOST_USER_BLK_SERVER(obj);
-
-    vhost_user_blk_server_start(vub, errp);
+    return 0;
 }
 
-static void vhost_user_blk_server_class_init(ObjectClass *klass,
-                                             void *class_data)
+static void vu_blk_exp_delete(BlockExport *exp)
 {
-    UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
-    ucc->complete = vhost_user_blk_server_complete;
-
-    object_class_property_add_bool(klass, "writable",
-                                   vu_get_block_writable,
-                                   vu_set_block_writable);
-
-    object_class_property_add_str(klass, "node-name",
-                                  vu_get_node_name,
-                                  vu_set_node_name);
-
-    object_class_property_add_str(klass, "unix-socket",
-                                  vu_get_unix_socket,
-                                  vu_set_unix_socket);
+    VuBlkExport *vexp = container_of(exp, VuBlkExport, export);
 
-    object_class_property_add(klass, "logical-block-size", "uint32",
-                              vu_get_blk_size, vu_set_blk_size,
-                              NULL, NULL);
+    blk_remove_aio_context_notifier(exp->blk, blk_aio_attached, blk_aio_detach,
+                                    vexp);
 }
 
-static const TypeInfo vhost_user_blk_server_info = {
-    .name = TYPE_VHOST_USER_BLK_SERVER,
-    .parent = TYPE_OBJECT,
-    .instance_size = sizeof(VuBlockDev),
-    .instance_finalize = vhost_user_blk_server_instance_finalize,
-    .class_init = vhost_user_blk_server_class_init,
-    .interfaces = (InterfaceInfo[]) {
-        {TYPE_USER_CREATABLE},
-        {}
-    },
+const BlockExportDriver blk_exp_vhost_user_blk = {
+    .type               = BLOCK_EXPORT_TYPE_VHOST_USER_BLK,
+    .instance_size      = sizeof(VuBlkExport),
+    .create             = vu_blk_exp_create,
+    .delete             = vu_blk_exp_delete,
+    .request_shutdown   = vu_blk_exp_request_shutdown,
 };
-
-static void vhost_user_blk_server_register_types(void)
-{
-    type_register_static(&vhost_user_blk_server_info);
-}
-
-type_init(vhost_user_blk_server_register_types)
diff --git a/tests/qtest/vhost-user-blk-test.c b/tests/qtest/vhost-user-blk-test.c
index XXXXXXX..XXXXXXX 100644
--- a/tests/qtest/vhost-user-blk-test.c
+++ b/tests/qtest/vhost-user-blk-test.c
@@ -XXX,XX +XXX,XX @@ static char *start_vhost_user_blk(GString *cmd_line, int vus_instances)
         img_path = drive_create();
         g_string_append_printf(storage_daemon_command,
             "--blockdev driver=file,node-name=disk%d,filename=%s "
-            "--object vhost-user-blk-server,id=disk%d,unix-socket=%s,"
+            "--export type=vhost-user-blk,id=disk%d,addr.type=unix,addr.path=%s,"
             "node-name=disk%i,writable=on ",
             i, img_path, i, sock_path, i);
 
diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
                              Error **errp)
 {
     QEMUBH *bh;
-    QIONetListener *listener = qio_net_listener_new();
+    QIONetListener *listener;
+
+    if (socket_addr->type != SOCKET_ADDRESS_TYPE_UNIX &&
+        socket_addr->type != SOCKET_ADDRESS_TYPE_FD) {
+        error_setg(errp, "Only socket address types 'unix' and 'fd' are supported");
+        return false;
+    }
+
+    listener = qio_net_listener_new();
     if (qio_net_listener_open_sync(listener, socket_addr, 1,
                                    errp) < 0) {
         object_unref(OBJECT(listener));
diff --git a/block/export/meson.build b/block/export/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/block/export/meson.build
+++ b/block/export/meson.build
@@ -1 +1,2 @@
 block_ss.add(files('export.c'))
+block_ss.add(when: 'CONFIG_LINUX', if_true: files('vhost-user-blk-server.c', '../../contrib/libvhost-user/libvhost-user.c'))
diff --git a/block/meson.build b/block/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/block/meson.build
+++ b/block/meson.build
@@ -XXX,XX +XXX,XX @@ block_ss.add(when: 'CONFIG_WIN32', if_true: files('file-win32.c', 'win32-aio.c')
 block_ss.add(when: 'CONFIG_POSIX', if_true: [files('file-posix.c'), coref, iokit])
 block_ss.add(when: 'CONFIG_LIBISCSI', if_true: files('iscsi-opts.c'))
 block_ss.add(when: 'CONFIG_LINUX', if_true: files('nvme.c'))
-block_ss.add(when: 'CONFIG_LINUX', if_true: files('export/vhost-user-blk-server.c', '../contrib/libvhost-user/libvhost-user.c'))
 block_ss.add(when: 'CONFIG_REPLICATION', if_true: files('replication.c'))
 block_ss.add(when: 'CONFIG_SHEEPDOG', if_true: files('sheepdog.c'))
 block_ss.add(when: ['CONFIG_LINUX_AIO', libaio], if_true: files('linux-aio.c'))
-- 
2.26.2

Headers used by other subsystems are located in include/. Also add the
vhost-user-server and vhost-user-blk-server headers to MAINTAINERS.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200924151549.913737-13-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 MAINTAINERS                                | 4 +++-
 {util => include/qemu}/vhost-user-server.h | 0
 block/export/vhost-user-blk-server.c       | 2 +-
 util/vhost-user-server.c                   | 2 +-
 4 files changed, 5 insertions(+), 3 deletions(-)
 rename {util => include/qemu}/vhost-user-server.h (100%)

diff --git a/MAINTAINERS b/MAINTAINERS
index XXXXXXX..XXXXXXX 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -XXX,XX +XXX,XX @@ Vhost-user block device backend server
 M: Coiby Xu <Coiby.Xu@gmail.com>
 S: Maintained
 F: block/export/vhost-user-blk-server.c
-F: util/vhost-user-server.c
+F: block/export/vhost-user-blk-server.h
+F: include/qemu/vhost-user-server.h
 F: tests/qtest/vhost-user-blk-test.c
 F: tests/qtest/libqos/vhost-user-blk.c
+F: util/vhost-user-server.c
 
 Replication
 M: Wen Congyang <wencongyang2@huawei.com>
diff --git a/util/vhost-user-server.h b/include/qemu/vhost-user-server.h
similarity index 100%
rename from util/vhost-user-server.h
rename to include/qemu/vhost-user-server.h
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.c
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@
 #include "block/block.h"
 #include "contrib/libvhost-user/libvhost-user.h"
 #include "standard-headers/linux/virtio_blk.h"
-#include "util/vhost-user-server.h"
+#include "qemu/vhost-user-server.h"
 #include "vhost-user-blk-server.h"
 #include "qapi/error.h"
 #include "qom/object_interfaces.h"
diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@
  */
 #include "qemu/osdep.h"
 #include "qemu/main-loop.h"
+#include "qemu/vhost-user-server.h"
 #include "block/aio-wait.h"
-#include "vhost-user-server.h"
 
 /*
  * Theory of operation:
-- 
2.26.2

Don't compile contrib/libvhost-user/libvhost-user.c again. Instead build
the static library once and then reuse it throughout QEMU.

Also switch from CONFIG_LINUX to CONFIG_VHOST_USER, which is what the
vhost-user tools (vhost-user-gpu, etc) do.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200924151549.913737-14-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/export/export.c             | 8 ++++----
 block/export/meson.build          | 2 +-
 contrib/libvhost-user/meson.build | 1 +
 meson.build                       | 6 +++++-
 tests/qtest/meson.build           | 2 +-
 util/meson.build                  | 4 +++-
 6 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/block/export/export.c b/block/export/export.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/export.c
+++ b/block/export/export.c
@@ -XXX,XX +XXX,XX @@
 #include "sysemu/block-backend.h"
 #include "block/export.h"
 #include "block/nbd.h"
-#if CONFIG_LINUX
-#include "block/export/vhost-user-blk-server.h"
-#endif
 #include "qapi/error.h"
 #include "qapi/qapi-commands-block-export.h"
 #include "qapi/qapi-events-block-export.h"
 #include "qemu/id.h"
+#ifdef CONFIG_VHOST_USER
+#include "vhost-user-blk-server.h"
+#endif
 
 static const BlockExportDriver *blk_exp_drivers[] = {
     &blk_exp_nbd,
-#if CONFIG_LINUX
+#ifdef CONFIG_VHOST_USER
     &blk_exp_vhost_user_blk,
 #endif
 };
diff --git a/block/export/meson.build b/block/export/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/block/export/meson.build
+++ b/block/export/meson.build
@@ -XXX,XX +XXX,XX @@
 block_ss.add(files('export.c'))
-block_ss.add(when: 'CONFIG_LINUX', if_true: files('vhost-user-blk-server.c', '../../contrib/libvhost-user/libvhost-user.c'))
+block_ss.add(when: 'CONFIG_VHOST_USER', if_true: files('vhost-user-blk-server.c'))
diff --git a/contrib/libvhost-user/meson.build b/contrib/libvhost-user/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/contrib/libvhost-user/meson.build
+++ b/contrib/libvhost-user/meson.build
@@ -XXX,XX +XXX,XX @@
 libvhost_user = static_library('vhost-user',
                                files('libvhost-user.c', 'libvhost-user-glib.c'),
                                build_by_default: false)
+vhost_user = declare_dependency(link_with: libvhost_user)
diff --git a/meson.build b/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/meson.build
+++ b/meson.build
@@ -XXX,XX +XXX,XX @@ trace_events_subdirs += [
   'util',
 ]
 
+vhost_user = not_found
+if 'CONFIG_VHOST_USER' in config_host
+  subdir('contrib/libvhost-user')
+endif
+
 subdir('qapi')
 subdir('qobject')
 subdir('stubs')
@@ -XXX,XX +XXX,XX @@ if have_tools
              install: true)
 
   if 'CONFIG_VHOST_USER' in config_host
-    subdir('contrib/libvhost-user')
     subdir('contrib/vhost-user-blk')
     subdir('contrib/vhost-user-gpu')
     subdir('contrib/vhost-user-input')
diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/tests/qtest/meson.build
+++ b/tests/qtest/meson.build
@@ -XXX,XX +XXX,XX @@ qos_test_ss.add(
 )
 qos_test_ss.add(when: 'CONFIG_VIRTFS', if_true: files('virtio-9p-test.c'))
 qos_test_ss.add(when: 'CONFIG_VHOST_USER', if_true: files('vhost-user-test.c'))
-qos_test_ss.add(when: ['CONFIG_LINUX', 'CONFIG_TOOLS'], if_true: files('vhost-user-blk-test.c'))
+qos_test_ss.add(when: ['CONFIG_VHOST_USER', 'CONFIG_TOOLS'], if_true: files('vhost-user-blk-test.c'))
 
 extra_qtest_deps = {
   'bios-tables-test': [io],
diff --git a/util/meson.build b/util/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/util/meson.build
+++ b/util/meson.build
@@ -XXX,XX +XXX,XX @@ if have_block
   util_ss.add(files('main-loop.c'))
   util_ss.add(files('nvdimm-utils.c'))
   util_ss.add(files('qemu-coroutine.c', 'qemu-coroutine-lock.c', 'qemu-coroutine-io.c'))
-  util_ss.add(when: 'CONFIG_LINUX', if_true: files('vhost-user-server.c'))
+  util_ss.add(when: 'CONFIG_VHOST_USER', if_true: [
+    files('vhost-user-server.c'), vhost_user
+  ])
   util_ss.add(files('block-helpers.c'))
   util_ss.add(files('qemu-coroutine-sleep.c'))
   util_ss.add(files('qemu-co-shared-resource.c'))
-- 
2.26.2

Introduce libblkdev.fa to avoid recompiling blockdev_ss twice.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200929125516.186715-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 meson.build                | 12 ++++++++++--
 storage-daemon/meson.build |  3 +--
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/meson.build b/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/meson.build
+++ b/meson.build
@@ -XXX,XX +XXX,XX @@ blockdev_ss.add(files(
 blockdev_ss.add(when: 'CONFIG_POSIX', if_true: files('os-posix.c'))
 softmmu_ss.add(when: 'CONFIG_WIN32', if_true: [files('os-win32.c')])
 
-softmmu_ss.add_all(blockdev_ss)
 softmmu_ss.add(files(
   'bootdevice.c',
   'dma-helpers.c',
@@ -XXX,XX +XXX,XX @@ block = declare_dependency(link_whole: [libblock],
                            link_args: '@block.syms',
                            dependencies: [crypto, io])
 
+blockdev_ss = blockdev_ss.apply(config_host, strict: false)
+libblockdev = static_library('blockdev', blockdev_ss.sources() + genh,
+                             dependencies: blockdev_ss.dependencies(),
+                             name_suffix: 'fa',
+                             build_by_default: false)
+
+blockdev = declare_dependency(link_whole: [libblockdev],
+                              dependencies: [block])
+
 qmp_ss = qmp_ss.apply(config_host, strict: false)
 libqmp = static_library('qmp', qmp_ss.sources() + genh,
                         dependencies: qmp_ss.dependencies(),
@@ -XXX,XX +XXX,XX @@ foreach m : block_mods + softmmu_mods
                 install_dir: config_host['qemu_moddir'])
 endforeach
 
-softmmu_ss.add(authz, block, chardev, crypto, io, qmp)
+softmmu_ss.add(authz, blockdev, chardev, crypto, io, qmp)
 common_ss.add(qom, qemuutil)
 
 common_ss.add_all(when: 'CONFIG_SOFTMMU', if_true: [softmmu_ss])
diff --git a/storage-daemon/meson.build b/storage-daemon/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/storage-daemon/meson.build
+++ b/storage-daemon/meson.build
@@ -XXX,XX +XXX,XX @@
 qsd_ss = ss.source_set()
 qsd_ss.add(files('qemu-storage-daemon.c'))
-qsd_ss.add(block, chardev, qmp, qom, qemuutil)
-qsd_ss.add_all(blockdev_ss)
+qsd_ss.add(blockdev, chardev, qmp, qom, qemuutil)
 
 subdir('qapi')
 
-- 
2.26.2

Block exports are used by softmmu, qemu-storage-daemon, and qemu-nbd.
They are not used by other programs and are not otherwise needed in
libblock.

Undo the recent move of blockdev-nbd.c from blockdev_ss into block_ss.
Since bdrv_close_all() (libblock) calls blk_exp_close_all()
(libblockdev) a stub function is required..

Make qemu-nbd.c use signal handling utility functions instead of
duplicating the code. This helps because os-posix.c is in libblockdev
and it depends on a qemu_system_killed() symbol that qemu-nbd.c lacks.
Once we use the signal handling utility functions we also end up
providing the necessary symbol.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20200929125516.186715-4-stefanha@redhat.com
[Fixed s/ndb/nbd/ typo in commit description as suggested by Eric Blake
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 qemu-nbd.c                | 25 +++++++++----------------
 stubs/blk-exp-close-all.c |  7 +++++++
 block/export/meson.build  |  4 ++--
 meson.build               |  4 ++--
 nbd/meson.build           |  2 ++
 stubs/meson.build         |  1 +
 6 files changed, 23 insertions(+), 20 deletions(-)
 create mode 100644 stubs/blk-exp-close-all.c

diff --git a/qemu-nbd.c b/qemu-nbd.c
index XXXXXXX..XXXXXXX 100644
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -XXX,XX +XXX,XX @@
 #include "qapi/error.h"
 #include "qemu/cutils.h"
 #include "sysemu/block-backend.h"
+#include "sysemu/runstate.h" /* for qemu_system_killed() prototype */
 #include "block/block_int.h"
 #include "block/nbd.h"
 #include "qemu/main-loop.h"
@@ -XXX,XX +XXX,XX @@ QEMU_COPYRIGHT "\n"
     , name);
 }
 
-#ifdef CONFIG_POSIX
-static void termsig_handler(int signum)
+#if CONFIG_POSIX
+/*
+ * The client thread uses SIGTERM to interrupt the server.  A signal
+ * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
+ */
+void qemu_system_killed(int signum, pid_t pid)
 {
     qatomic_cmpxchg(&state, RUNNING, TERMINATE);
     qemu_notify_event();
@@ -XXX,XX +XXX,XX @@ int main(int argc, char **argv)
     const char *pid_file_name = NULL;
     BlockExportOptions *export_opts;
 
-#ifdef CONFIG_POSIX
-    /*
-     * Exit gracefully on various signals, which includes SIGTERM used
-     * by 'qemu-nbd -v -c'.
-     */
-    struct sigaction sa_sigterm;
-    memset(&sa_sigterm, 0, sizeof(sa_sigterm));
-    sa_sigterm.sa_handler = termsig_handler;
-    sigaction(SIGTERM, &sa_sigterm, NULL);
-    sigaction(SIGINT, &sa_sigterm, NULL);
-    sigaction(SIGHUP, &sa_sigterm, NULL);
-
-    signal(SIGPIPE, SIG_IGN);
-#endif
+    os_setup_early_signal_handling();
+    os_setup_signal_handling();
 
     socket_init();
     error_init(argv[0]);
diff --git a/stubs/blk-exp-close-all.c b/stubs/blk-exp-close-all.c
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/stubs/blk-exp-close-all.c
@@ -XXX,XX +XXX,XX @@
+#include "qemu/osdep.h"
+#include "block/export.h"
+
+/* Only used in programs that support block exports (libblockdev.fa) */
+void blk_exp_close_all(void)
+{
+}
diff --git a/block/export/meson.build b/block/export/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/block/export/meson.build
+++ b/block/export/meson.build
@@ -XXX,XX +XXX,XX @@
-block_ss.add(files('export.c'))
-block_ss.add(when: 'CONFIG_VHOST_USER', if_true: files('vhost-user-blk-server.c'))
+blockdev_ss.add(files('export.c'))
+blockdev_ss.add(when: 'CONFIG_VHOST_USER', if_true: files('vhost-user-blk-server.c'))
diff --git a/meson.build b/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/meson.build
+++ b/meson.build
@@ -XXX,XX +XXX,XX @@ subdir('dump')
 
 block_ss.add(files(
   'block.c',
-  'blockdev-nbd.c',
   'blockjob.c',
   'job.c',
   'qemu-io-cmds.c',
@@ -XXX,XX +XXX,XX @@ subdir('block')
 
 blockdev_ss.add(files(
   'blockdev.c',
+  'blockdev-nbd.c',
   'iothread.c',
   'job-qmp.c',
 ))
@@ -XXX,XX +XXX,XX @@ if have_tools
   qemu_io = executable('qemu-io', files('qemu-io.c'),
              dependencies: [block, qemuutil], install: true)
   qemu_nbd = executable('qemu-nbd', files('qemu-nbd.c'),
-               dependencies: [block, qemuutil], install: true)
+               dependencies: [blockdev, qemuutil], install: true)
 
   subdir('storage-daemon')
   subdir('contrib/rdmacm-mux')
diff --git a/nbd/meson.build b/nbd/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/nbd/meson.build
+++ b/nbd/meson.build
@@ -XXX,XX +XXX,XX @@
 block_ss.add(files(
   'client.c',
   'common.c',
+))
+blockdev_ss.add(files(
   'server.c',
 ))
diff --git a/stubs/meson.build b/stubs/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/stubs/meson.build
+++ b/stubs/meson.build
@@ -XXX,XX +XXX,XX @@
 stub_ss.add(files('arch_type.c'))
 stub_ss.add(files('bdrv-next-monitor-owned.c'))
 stub_ss.add(files('blk-commit-all.c'))
+stub_ss.add(files('blk-exp-close-all.c'))
 stub_ss.add(files('blockdev-close-all-bdrv-states.c'))
 stub_ss.add(files('change-state-handler.c'))
 stub_ss.add(files('cmos.c'))
-- 
2.26.2

Make it possible to specify the iothread where the export will run. By
default the block node can be moved to other AioContexts later and the
export will follow. The fixed-iothread option forces strict behavior
that prevents changing AioContext while the export is active. See the
QAPI docs for details.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200929125516.186715-5-stefanha@redhat.com
[Fix stray '#' character in block-export.json and add missing "(since:
5.2)" as suggested by Eric Blake.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 qapi/block-export.json               | 11 ++++++++++
 block/export/export.c                | 31 +++++++++++++++++++++++++++-
 block/export/vhost-user-blk-server.c |  5 ++++-
 nbd/server.c                         |  2 --
 4 files changed, 45 insertions(+), 4 deletions(-)

diff --git a/qapi/block-export.json b/qapi/block-export.json
index XXXXXXX..XXXXXXX 100644
--- a/qapi/block-export.json
+++ b/qapi/block-export.json
@@ -XXX,XX +XXX,XX @@
 #                export before completion is signalled. (since: 5.2;
 #                default: false)
 #
+# @iothread: The name of the iothread object where the export will run. The
+#            default is to use the thread currently associated with the
+#            block node. (since: 5.2)
+#
+# @fixed-iothread: True prevents the block node from being moved to another
+#                  thread while the export is active. If true and @iothread is
+#                  given, export creation fails if the block node cannot be
+#                  moved to the iothread. The default is false. (since: 5.2)
+#
 # Since: 4.2
 ##
 { 'union': 'BlockExportOptions',
   'base': { 'type': 'BlockExportType',
             'id': 'str',
+	    '*fixed-iothread': 'bool',
+	    '*iothread': 'str',
             'node-name': 'str',
             '*writable': 'bool',
             '*writethrough': 'bool' },
diff --git a/block/export/export.c b/block/export/export.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/export.c
+++ b/block/export/export.c
@@ -XXX,XX +XXX,XX @@
 
 #include "block/block.h"
 #include "sysemu/block-backend.h"
+#include "sysemu/iothread.h"
 #include "block/export.h"
 #include "block/nbd.h"
 #include "qapi/error.h"
@@ -XXX,XX +XXX,XX @@ static const BlockExportDriver *blk_exp_find_driver(BlockExportType type)
 
 BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
 {
+    bool fixed_iothread = export->has_fixed_iothread && export->fixed_iothread;
     const BlockExportDriver *drv;
     BlockExport *exp = NULL;
     BlockDriverState *bs;
-    BlockBackend *blk;
+    BlockBackend *blk = NULL;
     AioContext *ctx;
     uint64_t perm;
     int ret;
@@ -XXX,XX +XXX,XX @@ BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
     ctx = bdrv_get_aio_context(bs);
     aio_context_acquire(ctx);
 
+    if (export->has_iothread) {
+        IOThread *iothread;
+        AioContext *new_ctx;
+
+        iothread = iothread_by_id(export->iothread);
+        if (!iothread) {
+            error_setg(errp, "iothread \"%s\" not found", export->iothread);
+            goto fail;
+        }
+
+        new_ctx = iothread_get_aio_context(iothread);
+
+        ret = bdrv_try_set_aio_context(bs, new_ctx, errp);
+        if (ret == 0) {
+            aio_context_release(ctx);
+            aio_context_acquire(new_ctx);
+            ctx = new_ctx;
+        } else if (fixed_iothread) {
+            goto fail;
+        }
+    }
+
     /*
      * Block exports are used for non-shared storage migration. Make sure
      * that BDRV_O_INACTIVE is cleared and the image is ready for write
@@ -XXX,XX +XXX,XX @@ BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
     }
 
     blk = blk_new(ctx, perm, BLK_PERM_ALL);
+
+    if (!fixed_iothread) {
+        blk_set_allow_aio_context_change(blk, true);
+    }
+
     ret = blk_insert_bs(blk, bs, errp);
     if (ret < 0) {
         goto fail;
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.c
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@ static const VuDevIface vu_blk_iface = {
 static void blk_aio_attached(AioContext *ctx, void *opaque)
 {
     VuBlkExport *vexp = opaque;
+
+    vexp->export.ctx = ctx;
     vhost_user_server_attach_aio_context(&vexp->vu_server, ctx);
 }
 
 static void blk_aio_detach(void *opaque)
 {
     VuBlkExport *vexp = opaque;
+
     vhost_user_server_detach_aio_context(&vexp->vu_server);
+    vexp->export.ctx = NULL;
 }
 
 static void
@@ -XXX,XX +XXX,XX @@ static int vu_blk_exp_create(BlockExport *exp, BlockExportOptions *opts,
     vu_blk_initialize_config(blk_bs(exp->blk), &vexp->blkcfg,
                                logical_block_size);
 
-    blk_set_allow_aio_context_change(exp->blk, true);
     blk_add_aio_context_notifier(exp->blk, blk_aio_attached, blk_aio_detach,
                                  vexp);
 
diff --git a/nbd/server.c b/nbd/server.c
index XXXXXXX..XXXXXXX 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -XXX,XX +XXX,XX @@ static int nbd_export_create(BlockExport *blk_exp, BlockExportOptions *exp_args,
         return ret;
     }
 
-    blk_set_allow_aio_context_change(blk, true);
-
     QTAILQ_INIT(&exp->clients);
     exp->name = g_strdup(arg->name);
     exp->description = g_strdup(arg->description);
-- 
2.26.2

Allow the number of queues to be configured using --export
vhost-user-blk,num-queues=N. This setting should match the QEMU --device
vhost-user-blk-pci,num-queues=N setting but QEMU vhost-user-blk.c lowers
its own value if the vhost-user-blk backend offers fewer queues than
QEMU.

The vhost-user-blk-server.c code is already capable of multi-queue. All
virtqueue processing runs in the same AioContext. No new locking is
needed.

Add the num-queues=N option and set the VIRTIO_BLK_F_MQ feature bit.
Note that the feature bit only announces the presence of the num_queues
configuration space field. It does not promise that there is more than 1
virtqueue, so we can set it unconditionally.

I tested multi-queue by running a random read fio test with numjobs=4 on
an -smp 4 guest. After the benchmark finished the guest /proc/interrupts
file showed activity on all 4 virtio-blk MSI-X. The /sys/block/vda/mq/
directory shows that Linux blk-mq has 4 queues configured.

An automated test is included in the next commit.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20201001144604.559733-2-stefanha@redhat.com
[Fixed accidental tab characters as suggested by Markus Armbruster
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 qapi/block-export.json               | 10 +++++++---
 block/export/vhost-user-blk-server.c | 24 ++++++++++++++++++------
 2 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/qapi/block-export.json b/qapi/block-export.json
index XXXXXXX..XXXXXXX 100644
--- a/qapi/block-export.json
+++ b/qapi/block-export.json
@@ -XXX,XX +XXX,XX @@
 #        SocketAddress types are supported. Passed fds must be UNIX domain
 #        sockets.
 # @logical-block-size: Logical block size in bytes. Defaults to 512 bytes.
+# @num-queues: Number of request virtqueues. Must be greater than 0. Defaults
+#              to 1.
 #
 # Since: 5.2
 ##
 { 'struct': 'BlockExportOptionsVhostUserBlk',
-  'data': { 'addr': 'SocketAddress', '*logical-block-size': 'size' } }
+  'data': { 'addr': 'SocketAddress',
+	    '*logical-block-size': 'size',
+            '*num-queues': 'uint16'} }
 
 ##
 # @NbdServerAddOptions:
@@ -XXX,XX +XXX,XX @@
 { 'union': 'BlockExportOptions',
   'base': { 'type': 'BlockExportType',
             'id': 'str',
-	    '*fixed-iothread': 'bool',
-	    '*iothread': 'str',
+            '*fixed-iothread': 'bool',
+            '*iothread': 'str',
             'node-name': 'str',
             '*writable': 'bool',
             '*writethrough': 'bool' },
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.c
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@
 #include "util/block-helpers.h"
 
 enum {
-    VHOST_USER_BLK_MAX_QUEUES = 1,
+    VHOST_USER_BLK_NUM_QUEUES_DEFAULT = 1,
 };
 struct virtio_blk_inhdr {
     unsigned char status;
@@ -XXX,XX +XXX,XX @@ static uint64_t vu_blk_get_features(VuDev *dev)
                1ull << VIRTIO_BLK_F_DISCARD |
                1ull << VIRTIO_BLK_F_WRITE_ZEROES |
                1ull << VIRTIO_BLK_F_CONFIG_WCE |
+               1ull << VIRTIO_BLK_F_MQ |
                1ull << VIRTIO_F_VERSION_1 |
                1ull << VIRTIO_RING_F_INDIRECT_DESC |
                1ull << VIRTIO_RING_F_EVENT_IDX |
@@ -XXX,XX +XXX,XX @@ static void blk_aio_detach(void *opaque)
 
 static void
 vu_blk_initialize_config(BlockDriverState *bs,
-                           struct virtio_blk_config *config, uint32_t blk_size)
+                         struct virtio_blk_config *config,
+                         uint32_t blk_size,
+                         uint16_t num_queues)
 {
     config->capacity = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
     config->blk_size = blk_size;
@@ -XXX,XX +XXX,XX @@ vu_blk_initialize_config(BlockDriverState *bs,
     config->seg_max = 128 - 2;
     config->min_io_size = 1;
     config->opt_io_size = 1;
-    config->num_queues = VHOST_USER_BLK_MAX_QUEUES;
+    config->num_queues = num_queues;
     config->max_discard_sectors = 32768;
     config->max_discard_seg = 1;
     config->discard_sector_alignment = config->blk_size >> 9;
@@ -XXX,XX +XXX,XX @@ static int vu_blk_exp_create(BlockExport *exp, BlockExportOptions *opts,
     BlockExportOptionsVhostUserBlk *vu_opts = &opts->u.vhost_user_blk;
     Error *local_err = NULL;
     uint64_t logical_block_size;
+    uint16_t num_queues = VHOST_USER_BLK_NUM_QUEUES_DEFAULT;
 
     vexp->writable = opts->writable;
     vexp->blkcfg.wce = 0;
@@ -XXX,XX +XXX,XX @@ static int vu_blk_exp_create(BlockExport *exp, BlockExportOptions *opts,
     }
     vexp->blk_size = logical_block_size;
     blk_set_guest_block_size(exp->blk, logical_block_size);
+
+    if (vu_opts->has_num_queues) {
+        num_queues = vu_opts->num_queues;
+    }
+    if (num_queues == 0) {
+        error_setg(errp, "num-queues must be greater than 0");
+        return -EINVAL;
+    }
+
     vu_blk_initialize_config(blk_bs(exp->blk), &vexp->blkcfg,
-                               logical_block_size);
+                             logical_block_size, num_queues);
 
     blk_add_aio_context_notifier(exp->blk, blk_aio_attached, blk_aio_detach,
                                  vexp);
 
     if (!vhost_user_server_start(&vexp->vu_server, vu_opts->addr, exp->ctx,
-                                 VHOST_USER_BLK_MAX_QUEUES, &vu_blk_iface,
-                                 errp)) {
+                                 num_queues, &vu_blk_iface, errp)) {
         blk_remove_aio_context_notifier(exp->blk, blk_aio_attached,
                                         blk_aio_detach, vexp);
         return -EADDRNOTAVAIL;
-- 
2.26.2

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20201001144604.559733-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 tests/qtest/vhost-user-blk-test.c | 81 +++++++++++++++++++++++++++++--
 1 file changed, 76 insertions(+), 5 deletions(-)

diff --git a/tests/qtest/vhost-user-blk-test.c b/tests/qtest/vhost-user-blk-test.c
index XXXXXXX..XXXXXXX 100644
--- a/tests/qtest/vhost-user-blk-test.c
+++ b/tests/qtest/vhost-user-blk-test.c
@@ -XXX,XX +XXX,XX @@ static void pci_hotplug(void *obj, void *data, QGuestAllocator *t_alloc)
     qpci_unplug_acpi_device_test(qts, "drv1", PCI_SLOT_HP);
 }
 
+static void multiqueue(void *obj, void *data, QGuestAllocator *t_alloc)
+{
+    QVirtioPCIDevice *pdev1 = obj;
+    QVirtioDevice *dev1 = &pdev1->vdev;
+    QVirtioPCIDevice *pdev8;
+    QVirtioDevice *dev8;
+    QTestState *qts = pdev1->pdev->bus->qts;
+    uint64_t features;
+    uint16_t num_queues;
+
+    /*
+     * The primary device has 1 queue and VIRTIO_BLK_F_MQ is not enabled. The
+     * VIRTIO specification allows VIRTIO_BLK_F_MQ to be enabled when there is
+     * only 1 virtqueue, but --device vhost-user-blk-pci doesn't do this (which
+     * is also spec-compliant).
+     */
+    features = qvirtio_get_features(dev1);
+    g_assert_cmpint(features & (1u << VIRTIO_BLK_F_MQ), ==, 0);
+    features = features & ~(QVIRTIO_F_BAD_FEATURE |
+                            (1u << VIRTIO_RING_F_INDIRECT_DESC) |
+                            (1u << VIRTIO_F_NOTIFY_ON_EMPTY) |
+                            (1u << VIRTIO_BLK_F_SCSI));
+    qvirtio_set_features(dev1, features);
+
+    /* Hotplug a secondary device with 8 queues */
+    qtest_qmp_device_add(qts, "vhost-user-blk-pci", "drv1",
+                         "{'addr': %s, 'chardev': 'char2', 'num-queues': 8}",
+                         stringify(PCI_SLOT_HP) ".0");
+
+    pdev8 = virtio_pci_new(pdev1->pdev->bus,
+                           &(QPCIAddress) {
+                               .devfn = QPCI_DEVFN(PCI_SLOT_HP, 0)
+                           });
+    g_assert_nonnull(pdev8);
+    g_assert_cmpint(pdev8->vdev.device_type, ==, VIRTIO_ID_BLOCK);
+
+    qos_object_start_hw(&pdev8->obj);
+
+    dev8 = &pdev8->vdev;
+    features = qvirtio_get_features(dev8);
+    g_assert_cmpint(features & (1u << VIRTIO_BLK_F_MQ),
+                    ==,
+                    (1u << VIRTIO_BLK_F_MQ));
+    features = features & ~(QVIRTIO_F_BAD_FEATURE |
+                            (1u << VIRTIO_RING_F_INDIRECT_DESC) |
+                            (1u << VIRTIO_F_NOTIFY_ON_EMPTY) |
+                            (1u << VIRTIO_BLK_F_SCSI) |
+                            (1u << VIRTIO_BLK_F_MQ));
+    qvirtio_set_features(dev8, features);
+
+    num_queues = qvirtio_config_readw(dev8,
+            offsetof(struct virtio_blk_config, num_queues));
+    g_assert_cmpint(num_queues, ==, 8);
+
+    qvirtio_pci_device_disable(pdev8);
+    qos_object_destroy(&pdev8->obj);
+
+    /* unplug secondary disk */
+    qpci_unplug_acpi_device_test(qts, "drv1", PCI_SLOT_HP);
+}
+
 /*
  * Check that setting the vring addr on a non-existent virtqueue does
  * not crash.
@@ -XXX,XX +XXX,XX @@ static void quit_storage_daemon(void *qmp_test_state)
     g_free(qmp_test_state);
 }
 
-static char *start_vhost_user_blk(GString *cmd_line, int vus_instances)
+static char *start_vhost_user_blk(GString *cmd_line, int vus_instances,
+                                  int num_queues)
 {
     const char *vhost_user_blk_bin = qtest_qemu_storage_daemon_binary();
     int fd, qmp_fd, i;
@@ -XXX,XX +XXX,XX @@ static char *start_vhost_user_blk(GString *cmd_line, int vus_instances)
         g_string_append_printf(storage_daemon_command,
             "--blockdev driver=file,node-name=disk%d,filename=%s "
             "--export type=vhost-user-blk,id=disk%d,addr.type=unix,addr.path=%s,"
-            "node-name=disk%i,writable=on ",
-            i, img_path, i, sock_path, i);
+            "node-name=disk%i,writable=on,num-queues=%d ",
+            i, img_path, i, sock_path, i, num_queues);
 
         g_string_append_printf(cmd_line, "-chardev socket,id=char%d,path=%s ",
                                i + 1, sock_path);
@@ -XXX,XX +XXX,XX @@ static char *start_vhost_user_blk(GString *cmd_line, int vus_instances)
 
 static void *vhost_user_blk_test_setup(GString *cmd_line, void *arg)
 {
-    start_vhost_user_blk(cmd_line, 1);
+    start_vhost_user_blk(cmd_line, 1, 1);
     return arg;
 }
 
@@ -XXX,XX +XXX,XX @@ static void *vhost_user_blk_test_setup(GString *cmd_line, void *arg)
 static void *vhost_user_blk_hotplug_test_setup(GString *cmd_line, void *arg)
 {
     /* "-chardev socket,id=char2" is used for pci_hotplug*/
-    start_vhost_user_blk(cmd_line, 2);
+    start_vhost_user_blk(cmd_line, 2, 1);
+    return arg;
+}
+
+static void *vhost_user_blk_multiqueue_test_setup(GString *cmd_line, void *arg)
+{
+    start_vhost_user_blk(cmd_line, 2, 8);
     return arg;
 }
 
@@ -XXX,XX +XXX,XX @@ static void register_vhost_user_blk_test(void)
 
     opts.before = vhost_user_blk_hotplug_test_setup;
     qos_add_test("hotplug", "vhost-user-blk-pci", pci_hotplug, &opts);
+
+    opts.before = vhost_user_blk_multiqueue_test_setup;
+    qos_add_test("multiqueue", "vhost-user-blk-pci", multiqueue, &opts);
 }
 
 libqos_init(register_vhost_user_blk_test);
-- 
2.26.2

From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

bdrv_co_block_status_above has several design problems with handling
short backing files:

1. With want_zeros=true, it may return ret with BDRV_BLOCK_ZERO but
without BDRV_BLOCK_ALLOCATED flag, when actually short backing file
which produces these after-EOF zeros is inside requested backing
sequence.

2. With want_zero=false, it may return pnum=0 prior to actual EOF,
because of EOF of short backing file.

Fix these things, making logic about short backing files clearer.

With fixed bdrv_block_status_above we also have to improve is_zero in
qcow2 code, otherwise iotest 154 will fail, because with this patch we
stop to merge zeros of different types (produced by fully unallocated
in the whole backing chain regions vs produced by short backing files).

Note also, that this patch leaves for another day the general problem
around block-status: misuse of BDRV_BLOCK_ALLOCATED as is-fs-allocated
vs go-to-backing.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20200924194003.22080-2-vsementsov@virtuozzo.com
[Fix s/comes/come/ as suggested by Eric Blake
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/io.c    | 68 ++++++++++++++++++++++++++++++++++++++++-----------
 block/qcow2.c | 16 ++++++++++--
 2 files changed, 68 insertions(+), 16 deletions(-)

diff --git a/block/io.c b/block/io.c
index XXXXXXX..XXXXXXX 100644
--- a/block/io.c
+++ b/block/io.c
@@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
                                   int64_t *map,
                                   BlockDriverState **file)
 {
+    int ret;
     BlockDriverState *p;
-    int ret = 0;
-    bool first = true;
+    int64_t eof = 0;
 
     assert(bs != base);
-    for (p = bs; p != base; p = bdrv_filter_or_cow_bs(p)) {
+
+    ret = bdrv_co_block_status(bs, want_zero, offset, bytes, pnum, map, file);
+    if (ret < 0 || *pnum == 0 || ret & BDRV_BLOCK_ALLOCATED) {
+        return ret;
+    }
+
+    if (ret & BDRV_BLOCK_EOF) {
+        eof = offset + *pnum;
+    }
+
+    assert(*pnum <= bytes);
+    bytes = *pnum;
+
+    for (p = bdrv_filter_or_cow_bs(bs); p != base;
+         p = bdrv_filter_or_cow_bs(p))
+    {
         ret = bdrv_co_block_status(p, want_zero, offset, bytes, pnum, map,
                                    file);
         if (ret < 0) {
-            break;
+            return ret;
         }
-        if (ret & BDRV_BLOCK_ZERO && ret & BDRV_BLOCK_EOF && !first) {
+        if (*pnum == 0) {
             /*
-             * Reading beyond the end of the file continues to read
-             * zeroes, but we can only widen the result to the
-             * unallocated length we learned from an earlier
-             * iteration.
+             * The top layer deferred to this layer, and because this layer is
+             * short, any zeroes that we synthesize beyond EOF behave as if they
+             * were allocated at this layer.
+             *
+             * We don't include BDRV_BLOCK_EOF into ret, as upper layer may be
+             * larger. We'll add BDRV_BLOCK_EOF if needed at function end, see
+             * below.
              */
+            assert(ret & BDRV_BLOCK_EOF);
             *pnum = bytes;
+            if (file) {
+                *file = p;
+            }
+            ret = BDRV_BLOCK_ZERO | BDRV_BLOCK_ALLOCATED;
+            break;
         }
-        if (ret & (BDRV_BLOCK_ZERO | BDRV_BLOCK_DATA)) {
+        if (ret & BDRV_BLOCK_ALLOCATED) {
+            /*
+             * We've found the node and the status, we must break.
+             *
+             * Drop BDRV_BLOCK_EOF, as it's not for upper layer, which may be
+             * larger. We'll add BDRV_BLOCK_EOF if needed at function end, see
+             * below.
+             */
+            ret &= ~BDRV_BLOCK_EOF;
             break;
         }
-        /* [offset, pnum] unallocated on this layer, which could be only
-         * the first part of [offset, bytes].  */
-        bytes = MIN(bytes, *pnum);
-        first = false;
+
+        /*
+         * OK, [offset, offset + *pnum) region is unallocated on this layer,
+         * let's continue the diving.
+         */
+        assert(*pnum <= bytes);
+        bytes = *pnum;
+    }
+
+    if (offset + *pnum == eof) {
+        ret |= BDRV_BLOCK_EOF;
     }
+
     return ret;
 }
 
diff --git a/block/qcow2.c b/block/qcow2.c
index XXXXXXX..XXXXXXX 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -XXX,XX +XXX,XX @@ static bool is_zero(BlockDriverState *bs, int64_t offset, int64_t bytes)
     if (!bytes) {
         return true;
     }
-    res = bdrv_block_status_above(bs, NULL, offset, bytes, &nr, NULL, NULL);
-    return res >= 0 && (res & BDRV_BLOCK_ZERO) && nr == bytes;
+
+    /*
+     * bdrv_block_status_above doesn't merge different types of zeros, for
+     * example, zeros which come from the region which is unallocated in
+     * the whole backing chain, and zeros which come because of a short
+     * backing file. So, we need a loop.
+     */
+    do {
+        res = bdrv_block_status_above(bs, NULL, offset, bytes, &nr, NULL, NULL);
+        offset += nr;
+        bytes -= nr;
+    } while (res >= 0 && (res & BDRV_BLOCK_ZERO) && nr && bytes);
+
+    return res >= 0 && (res & BDRV_BLOCK_ZERO) && bytes == 0;
 }
 
 static coroutine_fn int qcow2_co_pwrite_zeroes(BlockDriverState *bs,
-- 
2.26.2

From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

In order to reuse bdrv_common_block_status_above in
bdrv_is_allocated_above, let's support include_base parameter.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20200924194003.22080-3-vsementsov@virtuozzo.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/coroutines.h |  2 ++
 block/io.c         | 21 ++++++++++++++-------
 2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/block/coroutines.h b/block/coroutines.h
index XXXXXXX..XXXXXXX 100644
--- a/block/coroutines.h
+++ b/block/coroutines.h
@@ -XXX,XX +XXX,XX @@ bdrv_pwritev(BdrvChild *child, int64_t offset, unsigned int bytes,
 int coroutine_fn
 bdrv_co_common_block_status_above(BlockDriverState *bs,
                                   BlockDriverState *base,
+                                  bool include_base,
                                   bool want_zero,
                                   int64_t offset,
                                   int64_t bytes,
@@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
 int generated_co_wrapper
 bdrv_common_block_status_above(BlockDriverState *bs,
                                BlockDriverState *base,
+                               bool include_base,
                                bool want_zero,
                                int64_t offset,
                                int64_t bytes,
diff --git a/block/io.c b/block/io.c
index XXXXXXX..XXXXXXX 100644
--- a/block/io.c
+++ b/block/io.c
@@ -XXX,XX +XXX,XX @@ early_out:
 int coroutine_fn
 bdrv_co_common_block_status_above(BlockDriverState *bs,
                                   BlockDriverState *base,
+                                  bool include_base,
                                   bool want_zero,
                                   int64_t offset,
                                   int64_t bytes,
@@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
     BlockDriverState *p;
     int64_t eof = 0;
 
-    assert(bs != base);
+    assert(include_base || bs != base);
+    assert(!include_base || base); /* Can't include NULL base */
 
     ret = bdrv_co_block_status(bs, want_zero, offset, bytes, pnum, map, file);
-    if (ret < 0 || *pnum == 0 || ret & BDRV_BLOCK_ALLOCATED) {
+    if (ret < 0 || *pnum == 0 || ret & BDRV_BLOCK_ALLOCATED || bs == base) {
         return ret;
     }
 
@@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
     assert(*pnum <= bytes);
     bytes = *pnum;
 
-    for (p = bdrv_filter_or_cow_bs(bs); p != base;
+    for (p = bdrv_filter_or_cow_bs(bs); include_base || p != base;
          p = bdrv_filter_or_cow_bs(p))
     {
         ret = bdrv_co_block_status(p, want_zero, offset, bytes, pnum, map,
@@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
             break;
         }
 
+        if (p == base) {
+            assert(include_base);
+            break;
+        }
+
         /*
          * OK, [offset, offset + *pnum) region is unallocated on this layer,
          * let's continue the diving.
@@ -XXX,XX +XXX,XX @@ int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base,
                             int64_t offset, int64_t bytes, int64_t *pnum,
                             int64_t *map, BlockDriverState **file)
 {
-    return bdrv_common_block_status_above(bs, base, true, offset, bytes,
+    return bdrv_common_block_status_above(bs, base, false, true, offset, bytes,
                                           pnum, map, file);
 }
 
@@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset,
     int ret;
     int64_t dummy;
 
-    ret = bdrv_common_block_status_above(bs, bdrv_filter_or_cow_bs(bs), false,
-                                         offset, bytes, pnum ? pnum : &dummy,
-                                         NULL, NULL);
+    ret = bdrv_common_block_status_above(bs, bs, true, false, offset,
+                                         bytes, pnum ? pnum : &dummy, NULL,
+                                         NULL);
     if (ret < 0) {
         return ret;
     }
-- 
2.26.2

From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

We are going to reuse bdrv_common_block_status_above in
bdrv_is_allocated_above. bdrv_is_allocated_above may be called with
include_base == false and still bs == base (for ex. from img_rebase()).

So, support this corner case.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20200924194003.22080-4-vsementsov@virtuozzo.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/io.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/block/io.c b/block/io.c
index XXXXXXX..XXXXXXX 100644
--- a/block/io.c
+++ b/block/io.c
@@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
     BlockDriverState *p;
     int64_t eof = 0;
 
-    assert(include_base || bs != base);
     assert(!include_base || base); /* Can't include NULL base */
 
+    if (!include_base && bs == base) {
+        *pnum = bytes;
+        return 0;
+    }
+
     ret = bdrv_co_block_status(bs, want_zero, offset, bytes, pnum, map, file);
     if (ret < 0 || *pnum == 0 || ret & BDRV_BLOCK_ALLOCATED || bs == base) {
         return ret;
-- 
2.26.2

From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

bdrv_is_allocated_above wrongly handles short backing files: it reports
after-EOF space as UNALLOCATED which is wrong, as on read the data is
generated on the level of short backing file (if all overlays have
unallocated areas at that place).

Reusing bdrv_common_block_status_above fixes the issue and unifies code
path.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20200924194003.22080-5-vsementsov@virtuozzo.com
[Fix s/has/have/ as suggested by Eric Blake. Fix s/area/areas/.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/io.c | 43 +++++--------------------------------------
 1 file changed, 5 insertions(+), 38 deletions(-)

diff --git a/block/io.c b/block/io.c
index XXXXXXX..XXXXXXX 100644
--- a/block/io.c
+++ b/block/io.c
@@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset,
  * at 'offset + *pnum' may return the same allocation status (in other
  * words, the result is not necessarily the maximum possible range);
  * but 'pnum' will only be 0 when end of file is reached.
- *
  */
 int bdrv_is_allocated_above(BlockDriverState *top,
                             BlockDriverState *base,
                             bool include_base, int64_t offset,
                             int64_t bytes, int64_t *pnum)
 {
-    BlockDriverState *intermediate;
-    int ret;
-    int64_t n = bytes;
-
-    assert(base || !include_base);
-
-    intermediate = top;
-    while (include_base || intermediate != base) {
-        int64_t pnum_inter;
-        int64_t size_inter;
-
-        assert(intermediate);
-        ret = bdrv_is_allocated(intermediate, offset, bytes, &pnum_inter);
-        if (ret < 0) {
-            return ret;
-        }
-        if (ret) {
-            *pnum = pnum_inter;
-            return 1;
-        }
-
-        size_inter = bdrv_getlength(intermediate);
-        if (size_inter < 0) {
-            return size_inter;
-        }
-        if (n > pnum_inter &&
-            (intermediate == top || offset + pnum_inter < size_inter)) {
-            n = pnum_inter;
-        }
-
-        if (intermediate == base) {
-            break;
-        }
-
-        intermediate = bdrv_filter_or_cow_bs(intermediate);
+    int ret = bdrv_common_block_status_above(top, base, include_base, false,
+                                             offset, bytes, pnum, NULL, NULL);
+    if (ret < 0) {
+        return ret;
     }
 
-    *pnum = n;
-    return 0;
+    return !!(ret & BDRV_BLOCK_ALLOCATED);
 }
 
 int coroutine_fn
-- 
2.26.2

From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

These cases are fixed by previous patches around block_status and
is_allocated.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20200924194003.22080-6-vsementsov@virtuozzo.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 tests/qemu-iotests/274     | 20 +++++++++++
 tests/qemu-iotests/274.out | 68 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 88 insertions(+)

diff --git a/tests/qemu-iotests/274 b/tests/qemu-iotests/274
index XXXXXXX..XXXXXXX 100755
--- a/tests/qemu-iotests/274
+++ b/tests/qemu-iotests/274
@@ -XXX,XX +XXX,XX @@ with iotests.FilePath('base') as base, \
     iotests.qemu_io_log('-c', 'read -P 1 0 %d' % size_short, mid)
     iotests.qemu_io_log('-c', 'read -P 0 %d %d' % (size_short, size_diff), mid)
 
+    iotests.log('=== Testing qemu-img commit (top -> base) ===')
+
+    create_chain()
+    iotests.qemu_img_log('commit', '-b', base, top)
+    iotests.img_info_log(base)
+    iotests.qemu_io_log('-c', 'read -P 1 0 %d' % size_short, base)
+    iotests.qemu_io_log('-c', 'read -P 0 %d %d' % (size_short, size_diff), base)
+
+    iotests.log('=== Testing QMP active commit (top -> base) ===')
+
+    create_chain()
+    with create_vm() as vm:
+        vm.launch()
+        vm.qmp_log('block-commit', device='top', base_node='base',
+                   job_id='job0', auto_dismiss=False)
+        vm.run_job('job0', wait=5)
+
+    iotests.img_info_log(mid)
+    iotests.qemu_io_log('-c', 'read -P 1 0 %d' % size_short, base)
+    iotests.qemu_io_log('-c', 'read -P 0 %d %d' % (size_short, size_diff), base)
 
     iotests.log('== Resize tests ==')
 
diff --git a/tests/qemu-iotests/274.out b/tests/qemu-iotests/274.out
index XXXXXXX..XXXXXXX 100644
--- a/tests/qemu-iotests/274.out
+++ b/tests/qemu-iotests/274.out
@@ -XXX,XX +XXX,XX @@ read 1048576/1048576 bytes at offset 0
 read 1048576/1048576 bytes at offset 1048576
 1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 
+=== Testing qemu-img commit (top -> base) ===
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=2097152 lazy_refcounts=off refcount_bits=16
+
+Formatting 'TEST_DIR/PID-mid', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=1048576 backing_file=TEST_DIR/PID-base backing_fmt=qcow2 lazy_refcounts=off refcount_bits=16
+
+Formatting 'TEST_DIR/PID-top', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=2097152 backing_file=TEST_DIR/PID-mid backing_fmt=qcow2 lazy_refcounts=off refcount_bits=16
+
+wrote 2097152/2097152 bytes at offset 0
+2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+Image committed.
+
+image: TEST_IMG
+file format: IMGFMT
+virtual size: 2 MiB (2097152 bytes)
+cluster_size: 65536
+Format specific information:
+    compat: 1.1
+    compression type: zlib
+    lazy refcounts: false
+    refcount bits: 16
+    corrupt: false
+    extended l2: false
+
+read 1048576/1048576 bytes at offset 0
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+read 1048576/1048576 bytes at offset 1048576
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+=== Testing QMP active commit (top -> base) ===
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=2097152 lazy_refcounts=off refcount_bits=16
+
+Formatting 'TEST_DIR/PID-mid', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=1048576 backing_file=TEST_DIR/PID-base backing_fmt=qcow2 lazy_refcounts=off refcount_bits=16
+
+Formatting 'TEST_DIR/PID-top', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=2097152 backing_file=TEST_DIR/PID-mid backing_fmt=qcow2 lazy_refcounts=off refcount_bits=16
+
+wrote 2097152/2097152 bytes at offset 0
+2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+{"execute": "block-commit", "arguments": {"auto-dismiss": false, "base-node": "base", "device": "top", "job-id": "job0"}}
+{"return": {}}
+{"execute": "job-complete", "arguments": {"id": "job0"}}
+{"return": {}}
+{"data": {"device": "job0", "len": 1048576, "offset": 1048576, "speed": 0, "type": "commit"}, "event": "BLOCK_JOB_READY", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
+{"data": {"device": "job0", "len": 1048576, "offset": 1048576, "speed": 0, "type": "commit"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
+{"execute": "job-dismiss", "arguments": {"id": "job0"}}
+{"return": {}}
+image: TEST_IMG
+file format: IMGFMT
+virtual size: 1 MiB (1048576 bytes)
+cluster_size: 65536
+backing file: TEST_DIR/PID-base
+backing file format: IMGFMT
+Format specific information:
+    compat: 1.1
+    compression type: zlib
+    lazy refcounts: false
+    refcount bits: 16
+    corrupt: false
+    extended l2: false
+
+read 1048576/1048576 bytes at offset 0
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+read 1048576/1048576 bytes at offset 1048576
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
 == Resize tests ==
 === preallocation=off ===
 Formatting 'TEST_DIR/PID-base', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=6442450944 lazy_refcounts=off refcount_bits=16
-- 
2.26.2

The following changes since commit ac793156f650ae2d77834932d72224175ee69086:

Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20201020-1' into staging (2020-10-20 21:11:35 +0100)

are available in the Git repository at:

https://gitlab.com/stefanha/qemu.git tags/block-pull-request

for you to fetch changes up to 32a3fd65e7e3551337fd26bfc0e2f899d70c028c:

iotests: add commit top->base cases to 274 (2020-10-22 09:55:39 +0100)

----------------------------------------------------------------
Pull request

v2:
 * Fix format string issues on 32-bit hosts [Peter]
 * Fix qemu-nbd.c CONFIG_POSIX ifdef issue [Eric]
 * Fix missing eventfd.h header on macOS [Peter]
 * Drop unreliable vhost-user-blk test (will send a new patch when ready) [Peter]

This pull request contains the vhost-user-blk server by Coiby Xu along with my
additions, block/nvme.c alignment and hardware error statistics by Philippe
Mathieu-Daudé, and bdrv_co_block_status_above() fixes by Vladimir
Sementsov-Ogievskiy.

----------------------------------------------------------------

Coiby Xu (6):
  libvhost-user: Allow vu_message_read to be replaced
  libvhost-user: remove watch for kick_fd when de-initialize vu-dev
  util/vhost-user-server: generic vhost user server
  block: move logical block size check function to a common utility
    function
  block/export: vhost-user block device backend server
  MAINTAINERS: Add vhost-user block device backend server maintainer

Philippe Mathieu-Daudé (1):
  block/nvme: Add driver statistics for access alignment and hw errors

Stefan Hajnoczi (16):
  util/vhost-user-server: s/fileds/fields/ typo fix
  util/vhost-user-server: drop unnecessary QOM cast
  util/vhost-user-server: drop unnecessary watch deletion
  block/export: consolidate request structs into VuBlockReq
  util/vhost-user-server: drop unused DevicePanicNotifier
  util/vhost-user-server: fix memory leak in vu_message_read()
  util/vhost-user-server: check EOF when reading payload
  util/vhost-user-server: rework vu_client_trip() coroutine lifecycle
  block/export: report flush errors
  block/export: convert vhost-user-blk server to block export API
  util/vhost-user-server: move header to include/
  util/vhost-user-server: use static library in meson.build
  qemu-storage-daemon: avoid compiling blockdev_ss twice
  block: move block exports to libblockdev
  block/export: add iothread and fixed-iothread options
  block/export: add vhost-user-blk multi-queue support

-- 
2.26.2

From: Philippe Mathieu-Daudé <philmd@redhat.com>

Keep statistics of some hardware errors, and number of
aligned/unaligned I/O accesses.

QMP example booting a full RHEL 8.3 aarch64 guest:

From: Coiby Xu <coiby.xu@gmail.com>

Sharing QEMU devices via vhost-user protocol.

Only one vhost-user client can connect to the server one time.

diff --git a/util/vhost-user-server.h b/util/vhost-user-server.h
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/util/vhost-user-server.h
@@ -XXX,XX +XXX,XX @@
+/*
+ * Sharing QEMU devices via vhost-user protocol
+ *
+ * Copyright (c) Coiby Xu <coiby.xu@gmail.com>.
+ * Copyright (c) 2020 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ */
+
+#ifndef VHOST_USER_SERVER_H
+#define VHOST_USER_SERVER_H
+
+#include "contrib/libvhost-user/libvhost-user.h"
+#include "io/channel-socket.h"
+#include "io/channel-file.h"
+#include "io/net-listener.h"
+#include "qemu/error-report.h"
+#include "qapi/error.h"
+#include "standard-headers/linux/virtio_blk.h"
+
+typedef struct VuFdWatch {
+    VuDev *vu_dev;
+    int fd; /*kick fd*/
+    void *pvt;
+    vu_watch_cb cb;
+    bool processing;
+    QTAILQ_ENTRY(VuFdWatch) next;
+} VuFdWatch;
+
+typedef struct VuServer VuServer;
+typedef void DevicePanicNotifierFn(VuServer *server);
+
+struct VuServer {
+    QIONetListener *listener;
+    AioContext *ctx;
+    DevicePanicNotifierFn *device_panic_notifier;
+    int max_queues;
+    const VuDevIface *vu_iface;
+    VuDev vu_dev;
+    QIOChannel *ioc; /* The I/O channel with the client */
+    QIOChannelSocket *sioc; /* The underlying data channel with the client */
+    /* IOChannel for fd provided via VHOST_USER_SET_SLAVE_REQ_FD */
+    QIOChannel *ioc_slave;
+    QIOChannelSocket *sioc_slave;
+    Coroutine *co_trip; /* coroutine for processing VhostUserMsg */
+    QTAILQ_HEAD(, VuFdWatch) vu_fd_watches;
+    /* restart coroutine co_trip if AIOContext is changed */
+    bool aio_context_changed;
+    bool processing_msg;
+};
+
+bool vhost_user_server_start(VuServer *server,
+                             SocketAddress *unix_socket,
+                             AioContext *ctx,
+                             uint16_t max_queues,
+                             DevicePanicNotifierFn *device_panic_notifier,
+                             const VuDevIface *vu_iface,
+                             Error **errp);
+
+void vhost_user_server_stop(VuServer *server);
+
+void vhost_user_server_set_aio_context(VuServer *server, AioContext *ctx);
+
+#endif /* VHOST_USER_SERVER_H */
diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@
+/*
+ * Sharing QEMU devices via vhost-user protocol
+ *
+ * Copyright (c) Coiby Xu <coiby.xu@gmail.com>.
+ * Copyright (c) 2020 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ */
+#include "qemu/osdep.h"
+#include "qemu/main-loop.h"
+#include "vhost-user-server.h"
+
+static void vmsg_close_fds(VhostUserMsg *vmsg)
+{
+    int i;
+    for (i = 0; i < vmsg->fd_num; i++) {
+        close(vmsg->fds[i]);
+    }
+}
+
+static void vmsg_unblock_fds(VhostUserMsg *vmsg)
+{
+    int i;
+    for (i = 0; i < vmsg->fd_num; i++) {
+        qemu_set_nonblock(vmsg->fds[i]);
+    }
+}
+
+static void vu_accept(QIONetListener *listener, QIOChannelSocket *sioc,
+                      gpointer opaque);
+
+static void close_client(VuServer *server)
+{
+    /*
+     * Before closing the client
+     *
+     * 1. Let vu_client_trip stop processing new vhost-user msg
+     *
+     * 2. remove kick_handler
+     *
+     * 3. wait for the kick handler to be finished
+     *
+     * 4. wait for the current vhost-user msg to be finished processing
+     */
+
+    QIOChannelSocket *sioc = server->sioc;
+    /* When this is set vu_client_trip will stop new processing vhost-user message */
+    server->sioc = NULL;
+
+    VuFdWatch *vu_fd_watch, *next;
+    QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
+        aio_set_fd_handler(server->ioc->ctx, vu_fd_watch->fd, true, NULL,
+                           NULL, NULL, NULL);
+    }
+
+    while (!QTAILQ_EMPTY(&server->vu_fd_watches)) {
+        QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
+            if (!vu_fd_watch->processing) {
+                QTAILQ_REMOVE(&server->vu_fd_watches, vu_fd_watch, next);
+                g_free(vu_fd_watch);
+            }
+        }
+    }
+
+    while (server->processing_msg) {
+        if (server->ioc->read_coroutine) {
+            server->ioc->read_coroutine = NULL;
+            qio_channel_set_aio_fd_handler(server->ioc, server->ioc->ctx, NULL,
+                                           NULL, server->ioc);
+            server->processing_msg = false;
+        }
+    }
+
+    vu_deinit(&server->vu_dev);
+    object_unref(OBJECT(sioc));
+    object_unref(OBJECT(server->ioc));
+}
+
+static void panic_cb(VuDev *vu_dev, const char *buf)
+{
+    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+
+    /* avoid while loop in close_client */
+    server->processing_msg = false;
+
+    if (buf) {
+        error_report("vu_panic: %s", buf);
+    }
+
+    if (server->sioc) {
+        close_client(server);
+    }
+
+    if (server->device_panic_notifier) {
+        server->device_panic_notifier(server);
+    }
+
+    /*
+     * Set the callback function for network listener so another
+     * vhost-user client can connect to this server
+     */
+    qio_net_listener_set_client_func(server->listener,
+                                     vu_accept,
+                                     server,
+                                     NULL);
+}
+
+static bool coroutine_fn
+vu_message_read(VuDev *vu_dev, int conn_fd, VhostUserMsg *vmsg)
+{
+    struct iovec iov = {
+        .iov_base = (char *)vmsg,
+        .iov_len = VHOST_USER_HDR_SIZE,
+    };
+    int rc, read_bytes = 0;
+    Error *local_err = NULL;
+    /*
+     * Store fds/nfds returned from qio_channel_readv_full into
+     * temporary variables.
+     *
+     * VhostUserMsg is a packed structure, gcc will complain about passing
+     * pointer to a packed structure member if we pass &VhostUserMsg.fd_num
+     * and &VhostUserMsg.fds directly when calling qio_channel_readv_full,
+     * thus two temporary variables nfds and fds are used here.
+     */
+    size_t nfds = 0, nfds_t = 0;
+    const size_t max_fds = G_N_ELEMENTS(vmsg->fds);
+    int *fds_t = NULL;
+    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+    QIOChannel *ioc = server->ioc;
+
+    if (!ioc) {
+        error_report_err(local_err);
+        goto fail;
+    }
+
+    assert(qemu_in_coroutine());
+    do {
+        /*
+         * qio_channel_readv_full may have short reads, keeping calling it
+         * until getting VHOST_USER_HDR_SIZE or 0 bytes in total
+         */
+        rc = qio_channel_readv_full(ioc, &iov, 1, &fds_t, &nfds_t, &local_err);
+        if (rc < 0) {
+            if (rc == QIO_CHANNEL_ERR_BLOCK) {
+                qio_channel_yield(ioc, G_IO_IN);
+                continue;
+            } else {
+                error_report_err(local_err);
+                return false;
+            }
+        }
+        read_bytes += rc;
+        if (nfds_t > 0) {
+            if (nfds + nfds_t > max_fds) {
+                error_report("A maximum of %zu fds are allowed, "
+                             "however got %zu fds now",
+                             max_fds, nfds + nfds_t);
+                goto fail;
+            }
+            memcpy(vmsg->fds + nfds, fds_t,
+                   nfds_t *sizeof(vmsg->fds[0]));
+            nfds += nfds_t;
+            g_free(fds_t);
+        }
+        if (read_bytes == VHOST_USER_HDR_SIZE || rc == 0) {
+            break;
+        }
+        iov.iov_base = (char *)vmsg + read_bytes;
+        iov.iov_len = VHOST_USER_HDR_SIZE - read_bytes;
+    } while (true);
+
+    vmsg->fd_num = nfds;
+    /* qio_channel_readv_full will make socket fds blocking, unblock them */
+    vmsg_unblock_fds(vmsg);
+    if (vmsg->size > sizeof(vmsg->payload)) {
+        error_report("Error: too big message request: %d, "
+                     "size: vmsg->size: %u, "
+                     "while sizeof(vmsg->payload) = %zu",
+                     vmsg->request, vmsg->size, sizeof(vmsg->payload));
+        goto fail;
+    }
+
+    struct iovec iov_payload = {
+        .iov_base = (char *)&vmsg->payload,
+        .iov_len = vmsg->size,
+    };
+    if (vmsg->size) {
+        rc = qio_channel_readv_all_eof(ioc, &iov_payload, 1, &local_err);
+        if (rc == -1) {
+            error_report_err(local_err);
+            goto fail;
+        }
+    }
+
+    return true;
+
+fail:
+    vmsg_close_fds(vmsg);
+
+    return false;
+}
+
+
+static void vu_client_start(VuServer *server);
+static coroutine_fn void vu_client_trip(void *opaque)
+{
+    VuServer *server = opaque;
+
+    while (!server->aio_context_changed && server->sioc) {
+        server->processing_msg = true;
+        vu_dispatch(&server->vu_dev);
+        server->processing_msg = false;
+    }
+
+    if (server->aio_context_changed && server->sioc) {
+        server->aio_context_changed = false;
+        vu_client_start(server);
+    }
+}
+
+static void vu_client_start(VuServer *server)
+{
+    server->co_trip = qemu_coroutine_create(vu_client_trip, server);
+    aio_co_enter(server->ctx, server->co_trip);
+}
+
+/*
+ * a wrapper for vu_kick_cb
+ *
+ * since aio_dispatch can only pass one user data pointer to the
+ * callback function, pack VuDev and pvt into a struct. Then unpack it
+ * and pass them to vu_kick_cb
+ */
+static void kick_handler(void *opaque)
+{
+    VuFdWatch *vu_fd_watch = opaque;
+    vu_fd_watch->processing = true;
+    vu_fd_watch->cb(vu_fd_watch->vu_dev, 0, vu_fd_watch->pvt);
+    vu_fd_watch->processing = false;
+}
+
+
+static VuFdWatch *find_vu_fd_watch(VuServer *server, int fd)
+{
+
+    VuFdWatch *vu_fd_watch, *next;
+    QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
+        if (vu_fd_watch->fd == fd) {
+            return vu_fd_watch;
+        }
+    }
+    return NULL;
+}
+
+static void
+set_watch(VuDev *vu_dev, int fd, int vu_evt,
+          vu_watch_cb cb, void *pvt)
+{
+
+    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+    g_assert(vu_dev);
+    g_assert(fd >= 0);
+    g_assert(cb);
+
+    VuFdWatch *vu_fd_watch = find_vu_fd_watch(server, fd);
+
+    if (!vu_fd_watch) {
+        VuFdWatch *vu_fd_watch = g_new0(VuFdWatch, 1);
+
+        QTAILQ_INSERT_TAIL(&server->vu_fd_watches, vu_fd_watch, next);
+
+        vu_fd_watch->fd = fd;
+        vu_fd_watch->cb = cb;
+        qemu_set_nonblock(fd);
+        aio_set_fd_handler(server->ioc->ctx, fd, true, kick_handler,
+                           NULL, NULL, vu_fd_watch);
+        vu_fd_watch->vu_dev = vu_dev;
+        vu_fd_watch->pvt = pvt;
+    }
+}
+
+
+static void remove_watch(VuDev *vu_dev, int fd)
+{
+    VuServer *server;
+    g_assert(vu_dev);
+    g_assert(fd >= 0);
+
+    server = container_of(vu_dev, VuServer, vu_dev);
+
+    VuFdWatch *vu_fd_watch = find_vu_fd_watch(server, fd);
+
+    if (!vu_fd_watch) {
+        return;
+    }
+    aio_set_fd_handler(server->ioc->ctx, fd, true, NULL, NULL, NULL, NULL);
+
+    QTAILQ_REMOVE(&server->vu_fd_watches, vu_fd_watch, next);
+    g_free(vu_fd_watch);
+}
+
+
+static void vu_accept(QIONetListener *listener, QIOChannelSocket *sioc,
+                      gpointer opaque)
+{
+    VuServer *server = opaque;
+
+    if (server->sioc) {
+        warn_report("Only one vhost-user client is allowed to "
+                    "connect the server one time");
+        return;
+    }
+
+    if (!vu_init(&server->vu_dev, server->max_queues, sioc->fd, panic_cb,
+                 vu_message_read, set_watch, remove_watch, server->vu_iface)) {
+        error_report("Failed to initialize libvhost-user");
+        return;
+    }
+
+    /*
+     * Unset the callback function for network listener to make another
+     * vhost-user client keeping waiting until this client disconnects
+     */
+    qio_net_listener_set_client_func(server->listener,
+                                     NULL,
+                                     NULL,
+                                     NULL);
+    server->sioc = sioc;
+    /*
+     * Increase the object reference, so sioc will not freed by
+     * qio_net_listener_channel_func which will call object_unref(OBJECT(sioc))
+     */
+    object_ref(OBJECT(server->sioc));
+    qio_channel_set_name(QIO_CHANNEL(sioc), "vhost-user client");
+    server->ioc = QIO_CHANNEL(sioc);
+    object_ref(OBJECT(server->ioc));
+    qio_channel_attach_aio_context(server->ioc, server->ctx);
+    qio_channel_set_blocking(QIO_CHANNEL(server->sioc), false, NULL);
+    vu_client_start(server);
+}
+
+
+void vhost_user_server_stop(VuServer *server)
+{
+    if (server->sioc) {
+        close_client(server);
+    }
+
+    if (server->listener) {
+        qio_net_listener_disconnect(server->listener);
+        object_unref(OBJECT(server->listener));
+    }
+
+}
+
+void vhost_user_server_set_aio_context(VuServer *server, AioContext *ctx)
+{
+    VuFdWatch *vu_fd_watch, *next;
+    void *opaque = NULL;
+    IOHandler *io_read = NULL;
+    bool attach;
+
+    server->ctx = ctx ? ctx : qemu_get_aio_context();
+
+    if (!server->sioc) {
+        /* not yet serving any client*/
+        return;
+    }
+
+    if (ctx) {
+        qio_channel_attach_aio_context(server->ioc, ctx);
+        server->aio_context_changed = true;
+        io_read = kick_handler;
+        attach = true;
+    } else {
+        qio_channel_detach_aio_context(server->ioc);
+        /* server->ioc->ctx keeps the old AioConext */
+        ctx = server->ioc->ctx;
+        attach = false;
+    }
+
+    QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
+        if (vu_fd_watch->cb) {
+            opaque = attach ? vu_fd_watch : NULL;
+            aio_set_fd_handler(ctx, vu_fd_watch->fd, true,
+                               io_read, NULL, NULL,
+                               opaque);
+        }
+    }
+}
+
+
+bool vhost_user_server_start(VuServer *server,
+                             SocketAddress *socket_addr,
+                             AioContext *ctx,
+                             uint16_t max_queues,
+                             DevicePanicNotifierFn *device_panic_notifier,
+                             const VuDevIface *vu_iface,
+                             Error **errp)
+{
+    QIONetListener *listener = qio_net_listener_new();
+    if (qio_net_listener_open_sync(listener, socket_addr, 1,
+                                   errp) < 0) {
+        object_unref(OBJECT(listener));
+        return false;
+    }
+
+    /* zero out unspecified fileds */
+    *server = (VuServer) {
+        .listener              = listener,
+        .vu_iface              = vu_iface,
+        .max_queues            = max_queues,
+        .ctx                   = ctx,
+        .device_panic_notifier = device_panic_notifier,
+    };
+
+    qio_net_listener_set_name(server->listener, "vhost-user-backend-listener");
+
+    qio_net_listener_set_client_func(server->listener,
+                                     vu_accept,
+                                     server,
+                                     NULL);
+
+    QTAILQ_INIT(&server->vu_fd_watches);
+    return true;
+}
diff --git a/util/meson.build b/util/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/util/meson.build
+++ b/util/meson.build
@@ -XXX,XX +XXX,XX @@ if have_block
   util_ss.add(files('main-loop.c'))
   util_ss.add(files('nvdimm-utils.c'))
   util_ss.add(files('qemu-coroutine.c', 'qemu-coroutine-lock.c', 'qemu-coroutine-io.c'))
+  util_ss.add(when: 'CONFIG_LINUX', if_true: files('vhost-user-server.c'))
   util_ss.add(files('qemu-coroutine-sleep.c'))
   util_ss.add(files('qemu-co-shared-resource.c'))
   util_ss.add(files('thread-pool.c', 'qemu-timer.c'))
-- 
2.26.2

From: Coiby Xu <coiby.xu@gmail.com>

Move the constants from hw/core/qdev-properties.c to
util/block-helpers.h so that knowledge of the min/max values is

From: Coiby Xu <coiby.xu@gmail.com>

By making use of libvhost-user, block device drive can be shared to
the connected vhost-user client. Only one client can connect to the
server one time.

Since vhost-user-server needs a block drive to be created first, delay
the creation of this object.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20200918080912.321299-6-coiby.xu@gmail.com
[Shorten "vhost_user_blk_server" string to "vhost_user_blk" to avoid the
following compiler warning:
../block/export/vhost-user-blk-server.c:178:50: error: ‘%s’ directive output truncated writing 21 bytes into a region of size 20 [-Werror=format-truncation=]
and fix "Invalid size %ld ..." ssize_t format string arguments for
32-bit hosts.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/export/vhost-user-blk-server.h |  36 ++
 block/export/vhost-user-blk-server.c | 661 +++++++++++++++++++++++++++
 softmmu/vl.c                         |   4 +
 block/meson.build                    |   1 +
 4 files changed, 702 insertions(+)
 create mode 100644 block/export/vhost-user-blk-server.h
 create mode 100644 block/export/vhost-user-blk-server.c

diff --git a/block/export/vhost-user-blk-server.h b/block/export/vhost-user-blk-server.h
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/block/export/vhost-user-blk-server.h
@@ -XXX,XX +XXX,XX @@
+/*
+ * Sharing QEMU block devices via vhost-user protocal
+ *
+ * Copyright (c) Coiby Xu <coiby.xu@gmail.com>.
+ * Copyright (c) 2020 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ */
+
+#ifndef VHOST_USER_BLK_SERVER_H
+#define VHOST_USER_BLK_SERVER_H
+#include "util/vhost-user-server.h"
+
+typedef struct VuBlockDev VuBlockDev;
+#define TYPE_VHOST_USER_BLK_SERVER "vhost-user-blk-server"
+#define VHOST_USER_BLK_SERVER(obj) \
+   OBJECT_CHECK(VuBlockDev, obj, TYPE_VHOST_USER_BLK_SERVER)
+
+/* vhost user block device */
+struct VuBlockDev {
+    Object parent_obj;
+    char *node_name;
+    SocketAddress *addr;
+    AioContext *ctx;
+    VuServer vu_server;
+    bool running;
+    uint32_t blk_size;
+    BlockBackend *backend;
+    QIOChannelSocket *sioc;
+    QTAILQ_ENTRY(VuBlockDev) next;
+    struct virtio_blk_config blkcfg;
+    bool writable;
+};
+
+#endif /* VHOST_USER_BLK_SERVER_H */
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@
+/*
+ * Sharing QEMU block devices via vhost-user protocal
+ *
+ * Parts of the code based on nbd/server.c.
+ *
+ * Copyright (c) Coiby Xu <coiby.xu@gmail.com>.
+ * Copyright (c) 2020 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ */
+#include "qemu/osdep.h"
+#include "block/block.h"
+#include "vhost-user-blk-server.h"
+#include "qapi/error.h"
+#include "qom/object_interfaces.h"
+#include "sysemu/block-backend.h"
+#include "util/block-helpers.h"
+
+enum {
+    VHOST_USER_BLK_MAX_QUEUES = 1,
+};
+struct virtio_blk_inhdr {
+    unsigned char status;
+};
+
+typedef struct VuBlockReq {
+    VuVirtqElement *elem;
+    int64_t sector_num;
+    size_t size;
+    struct virtio_blk_inhdr *in;
+    struct virtio_blk_outhdr out;
+    VuServer *server;
+    struct VuVirtq *vq;
+} VuBlockReq;
+
+static void vu_block_req_complete(VuBlockReq *req)
+{
+    VuDev *vu_dev = &req->server->vu_dev;
+
+    /* IO size with 1 extra status byte */
+    vu_queue_push(vu_dev, req->vq, req->elem, req->size + 1);
+    vu_queue_notify(vu_dev, req->vq);
+
+    if (req->elem) {
+        free(req->elem);
+    }
+
+    g_free(req);
+}
+
+static VuBlockDev *get_vu_block_device_by_server(VuServer *server)
+{
+    return container_of(server, VuBlockDev, vu_server);
+}
+
+static int coroutine_fn
+vu_block_discard_write_zeroes(VuBlockReq *req, struct iovec *iov,
+                              uint32_t iovcnt, uint32_t type)
+{
+    struct virtio_blk_discard_write_zeroes desc;
+    ssize_t size = iov_to_buf(iov, iovcnt, 0, &desc, sizeof(desc));
+    if (unlikely(size != sizeof(desc))) {
+        error_report("Invalid size %zd, expect %zu", size, sizeof(desc));
+        return -EINVAL;
+    }
+
+    VuBlockDev *vdev_blk = get_vu_block_device_by_server(req->server);
+    uint64_t range[2] = { le64_to_cpu(desc.sector) << 9,
+                          le32_to_cpu(desc.num_sectors) << 9 };
+    if (type == VIRTIO_BLK_T_DISCARD) {
+        if (blk_co_pdiscard(vdev_blk->backend, range[0], range[1]) == 0) {
+            return 0;
+        }
+    } else if (type == VIRTIO_BLK_T_WRITE_ZEROES) {
+        if (blk_co_pwrite_zeroes(vdev_blk->backend,
+                                 range[0], range[1], 0) == 0) {
+            return 0;
+        }
+    }
+
+    return -EINVAL;
+}
+
+static void coroutine_fn vu_block_flush(VuBlockReq *req)
+{
+    VuBlockDev *vdev_blk = get_vu_block_device_by_server(req->server);
+    BlockBackend *backend = vdev_blk->backend;
+    blk_co_flush(backend);
+}
+
+struct req_data {
+    VuServer *server;
+    VuVirtq *vq;
+    VuVirtqElement *elem;
+};
+
+static void coroutine_fn vu_block_virtio_process_req(void *opaque)
+{
+    struct req_data *data = opaque;
+    VuServer *server = data->server;
+    VuVirtq *vq = data->vq;
+    VuVirtqElement *elem = data->elem;
+    uint32_t type;
+    VuBlockReq *req;
+
+    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+    BlockBackend *backend = vdev_blk->backend;
+
+    struct iovec *in_iov = elem->in_sg;
+    struct iovec *out_iov = elem->out_sg;
+    unsigned in_num = elem->in_num;
+    unsigned out_num = elem->out_num;
+    /* refer to hw/block/virtio_blk.c */
+    if (elem->out_num < 1 || elem->in_num < 1) {
+        error_report("virtio-blk request missing headers");
+        free(elem);
+        return;
+    }
+
+    req = g_new0(VuBlockReq, 1);
+    req->server = server;
+    req->vq = vq;
+    req->elem = elem;
+
+    if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out,
+                            sizeof(req->out)) != sizeof(req->out))) {
+        error_report("virtio-blk request outhdr too short");
+        goto err;
+    }
+
+    iov_discard_front(&out_iov, &out_num, sizeof(req->out));
+
+    if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) {
+        error_report("virtio-blk request inhdr too short");
+        goto err;
+    }
+
+    /* We always touch the last byte, so just see how big in_iov is.  */
+    req->in = (void *)in_iov[in_num - 1].iov_base
+              + in_iov[in_num - 1].iov_len
+              - sizeof(struct virtio_blk_inhdr);
+    iov_discard_back(in_iov, &in_num, sizeof(struct virtio_blk_inhdr));
+
+    type = le32_to_cpu(req->out.type);
+    switch (type & ~VIRTIO_BLK_T_BARRIER) {
+    case VIRTIO_BLK_T_IN:
+    case VIRTIO_BLK_T_OUT: {
+        ssize_t ret = 0;
+        bool is_write = type & VIRTIO_BLK_T_OUT;
+        req->sector_num = le64_to_cpu(req->out.sector);
+
+        int64_t offset = req->sector_num * vdev_blk->blk_size;
+        QEMUIOVector qiov;
+        if (is_write) {
+            qemu_iovec_init_external(&qiov, out_iov, out_num);
+            ret = blk_co_pwritev(backend, offset, qiov.size,
+                                 &qiov, 0);
+        } else {
+            qemu_iovec_init_external(&qiov, in_iov, in_num);
+            ret = blk_co_preadv(backend, offset, qiov.size,
+                                &qiov, 0);
+        }
+        if (ret >= 0) {
+            req->in->status = VIRTIO_BLK_S_OK;
+        } else {
+            req->in->status = VIRTIO_BLK_S_IOERR;
+        }
+        break;
+    }
+    case VIRTIO_BLK_T_FLUSH:
+        vu_block_flush(req);
+        req->in->status = VIRTIO_BLK_S_OK;
+        break;
+    case VIRTIO_BLK_T_GET_ID: {
+        size_t size = MIN(iov_size(&elem->in_sg[0], in_num),
+                          VIRTIO_BLK_ID_BYTES);
+        snprintf(elem->in_sg[0].iov_base, size, "%s", "vhost_user_blk");
+        req->in->status = VIRTIO_BLK_S_OK;
+        req->size = elem->in_sg[0].iov_len;
+        break;
+    }
+    case VIRTIO_BLK_T_DISCARD:
+    case VIRTIO_BLK_T_WRITE_ZEROES: {
+        int rc;
+        rc = vu_block_discard_write_zeroes(req, &elem->out_sg[1],
+                                           out_num, type);
+        if (rc == 0) {
+            req->in->status = VIRTIO_BLK_S_OK;
+        } else {
+            req->in->status = VIRTIO_BLK_S_IOERR;
+        }
+        break;
+    }
+    default:
+        req->in->status = VIRTIO_BLK_S_UNSUPP;
+        break;
+    }
+
+    vu_block_req_complete(req);
+    return;
+
+err:
+    free(elem);
+    g_free(req);
+    return;
+}
+
+static void vu_block_process_vq(VuDev *vu_dev, int idx)
+{
+    VuServer *server;
+    VuVirtq *vq;
+    struct req_data *req_data;
+
+    server = container_of(vu_dev, VuServer, vu_dev);
+    assert(server);
+
+    vq = vu_get_queue(vu_dev, idx);
+    assert(vq);
+    VuVirtqElement *elem;
+    while (1) {
+        elem = vu_queue_pop(vu_dev, vq, sizeof(VuVirtqElement) +
+                                    sizeof(VuBlockReq));
+        if (elem) {
+            req_data = g_new0(struct req_data, 1);
+            req_data->server = server;
+            req_data->vq = vq;
+            req_data->elem = elem;
+            Coroutine *co = qemu_coroutine_create(vu_block_virtio_process_req,
+                                                  req_data);
+            aio_co_enter(server->ioc->ctx, co);
+        } else {
+            break;
+        }
+    }
+}
+
+static void vu_block_queue_set_started(VuDev *vu_dev, int idx, bool started)
+{
+    VuVirtq *vq;
+
+    assert(vu_dev);
+
+    vq = vu_get_queue(vu_dev, idx);
+    vu_set_queue_handler(vu_dev, vq, started ? vu_block_process_vq : NULL);
+}
+
+static uint64_t vu_block_get_features(VuDev *dev)
+{
+    uint64_t features;
+    VuServer *server = container_of(dev, VuServer, vu_dev);
+    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+    features = 1ull << VIRTIO_BLK_F_SIZE_MAX |
+               1ull << VIRTIO_BLK_F_SEG_MAX |
+               1ull << VIRTIO_BLK_F_TOPOLOGY |
+               1ull << VIRTIO_BLK_F_BLK_SIZE |
+               1ull << VIRTIO_BLK_F_FLUSH |
+               1ull << VIRTIO_BLK_F_DISCARD |
+               1ull << VIRTIO_BLK_F_WRITE_ZEROES |
+               1ull << VIRTIO_BLK_F_CONFIG_WCE |
+               1ull << VIRTIO_F_VERSION_1 |
+               1ull << VIRTIO_RING_F_INDIRECT_DESC |
+               1ull << VIRTIO_RING_F_EVENT_IDX |
+               1ull << VHOST_USER_F_PROTOCOL_FEATURES;
+
+    if (!vdev_blk->writable) {
+        features |= 1ull << VIRTIO_BLK_F_RO;
+    }
+
+    return features;
+}
+
+static uint64_t vu_block_get_protocol_features(VuDev *dev)
+{
+    return 1ull << VHOST_USER_PROTOCOL_F_CONFIG |
+           1ull << VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD;
+}
+
+static int
+vu_block_get_config(VuDev *vu_dev, uint8_t *config, uint32_t len)
+{
+    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+    memcpy(config, &vdev_blk->blkcfg, len);
+
+    return 0;
+}
+
+static int
+vu_block_set_config(VuDev *vu_dev, const uint8_t *data,
+                    uint32_t offset, uint32_t size, uint32_t flags)
+{
+    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+    uint8_t wce;
+
+    /* don't support live migration */
+    if (flags != VHOST_SET_CONFIG_TYPE_MASTER) {
+        return -EINVAL;
+    }
+
+    if (offset != offsetof(struct virtio_blk_config, wce) ||
+        size != 1) {
+        return -EINVAL;
+    }
+
+    wce = *data;
+    vdev_blk->blkcfg.wce = wce;
+    blk_set_enable_write_cache(vdev_blk->backend, wce);
+    return 0;
+}
+
+/*
+ * When the client disconnects, it sends a VHOST_USER_NONE request
+ * and vu_process_message will simple call exit which cause the VM
+ * to exit abruptly.
+ * To avoid this issue,  process VHOST_USER_NONE request ahead
+ * of vu_process_message.
+ *
+ */
+static int vu_block_process_msg(VuDev *dev, VhostUserMsg *vmsg, int *do_reply)
+{
+    if (vmsg->request == VHOST_USER_NONE) {
+        dev->panic(dev, "disconnect");
+        return true;
+    }
+    return false;
+}
+
+static const VuDevIface vu_block_iface = {
+    .get_features          = vu_block_get_features,
+    .queue_set_started     = vu_block_queue_set_started,
+    .get_protocol_features = vu_block_get_protocol_features,
+    .get_config            = vu_block_get_config,
+    .set_config            = vu_block_set_config,
+    .process_msg           = vu_block_process_msg,
+};
+
+static void blk_aio_attached(AioContext *ctx, void *opaque)
+{
+    VuBlockDev *vub_dev = opaque;
+    aio_context_acquire(ctx);
+    vhost_user_server_set_aio_context(&vub_dev->vu_server, ctx);
+    aio_context_release(ctx);
+}
+
+static void blk_aio_detach(void *opaque)
+{
+    VuBlockDev *vub_dev = opaque;
+    AioContext *ctx = vub_dev->vu_server.ctx;
+    aio_context_acquire(ctx);
+    vhost_user_server_set_aio_context(&vub_dev->vu_server, NULL);
+    aio_context_release(ctx);
+}
+
+static void
+vu_block_initialize_config(BlockDriverState *bs,
+                           struct virtio_blk_config *config, uint32_t blk_size)
+{
+    config->capacity = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
+    config->blk_size = blk_size;
+    config->size_max = 0;
+    config->seg_max = 128 - 2;
+    config->min_io_size = 1;
+    config->opt_io_size = 1;
+    config->num_queues = VHOST_USER_BLK_MAX_QUEUES;
+    config->max_discard_sectors = 32768;
+    config->max_discard_seg = 1;
+    config->discard_sector_alignment = config->blk_size >> 9;
+    config->max_write_zeroes_sectors = 32768;
+    config->max_write_zeroes_seg = 1;
+}
+
+static VuBlockDev *vu_block_init(VuBlockDev *vu_block_device, Error **errp)
+{
+
+    BlockBackend *blk;
+    Error *local_error = NULL;
+    const char *node_name = vu_block_device->node_name;
+    bool writable = vu_block_device->writable;
+    uint64_t perm = BLK_PERM_CONSISTENT_READ;
+    int ret;
+
+    AioContext *ctx;
+
+    BlockDriverState *bs = bdrv_lookup_bs(node_name, node_name, &local_error);
+
+    if (!bs) {
+        error_propagate(errp, local_error);
+        return NULL;
+    }
+
+    if (bdrv_is_read_only(bs)) {
+        writable = false;
+    }
+
+    if (writable) {
+        perm |= BLK_PERM_WRITE;
+    }
+
+    ctx = bdrv_get_aio_context(bs);
+    aio_context_acquire(ctx);
+    bdrv_invalidate_cache(bs, NULL);
+    aio_context_release(ctx);
+
+    /*
+     * Don't allow resize while the vhost user server is running,
+     * otherwise we don't care what happens with the node.
+     */
+    blk = blk_new(bdrv_get_aio_context(bs), perm,
+                  BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED |
+                  BLK_PERM_WRITE | BLK_PERM_GRAPH_MOD);
+    ret = blk_insert_bs(blk, bs, errp);
+
+    if (ret < 0) {
+        goto fail;
+    }
+
+    blk_set_enable_write_cache(blk, false);
+
+    blk_set_allow_aio_context_change(blk, true);
+
+    vu_block_device->blkcfg.wce = 0;
+    vu_block_device->backend = blk;
+    if (!vu_block_device->blk_size) {
+        vu_block_device->blk_size = BDRV_SECTOR_SIZE;
+    }
+    vu_block_device->blkcfg.blk_size = vu_block_device->blk_size;
+    blk_set_guest_block_size(blk, vu_block_device->blk_size);
+    vu_block_initialize_config(bs, &vu_block_device->blkcfg,
+                                   vu_block_device->blk_size);
+    return vu_block_device;
+
+fail:
+    blk_unref(blk);
+    return NULL;
+}
+
+static void vu_block_deinit(VuBlockDev *vu_block_device)
+{
+    if (vu_block_device->backend) {
+        blk_remove_aio_context_notifier(vu_block_device->backend, blk_aio_attached,
+                                        blk_aio_detach, vu_block_device);
+    }
+
+    blk_unref(vu_block_device->backend);
+}
+
+static void vhost_user_blk_server_stop(VuBlockDev *vu_block_device)
+{
+    vhost_user_server_stop(&vu_block_device->vu_server);
+    vu_block_deinit(vu_block_device);
+}
+
+static void vhost_user_blk_server_start(VuBlockDev *vu_block_device,
+                                        Error **errp)
+{
+    AioContext *ctx;
+    SocketAddress *addr = vu_block_device->addr;
+
+    if (!vu_block_init(vu_block_device, errp)) {
+        return;
+    }
+
+    ctx = bdrv_get_aio_context(blk_bs(vu_block_device->backend));
+
+    if (!vhost_user_server_start(&vu_block_device->vu_server, addr, ctx,
+                                 VHOST_USER_BLK_MAX_QUEUES,
+                                 NULL, &vu_block_iface,
+                                 errp)) {
+        goto error;
+    }
+
+    blk_add_aio_context_notifier(vu_block_device->backend, blk_aio_attached,
+                                 blk_aio_detach, vu_block_device);
+    vu_block_device->running = true;
+    return;
+
+ error:
+    vu_block_deinit(vu_block_device);
+}
+
+static bool vu_prop_modifiable(VuBlockDev *vus, Error **errp)
+{
+    if (vus->running) {
+            error_setg(errp, "The property can't be modified "
+                       "while the server is running");
+            return false;
+    }
+    return true;
+}
+
+static void vu_set_node_name(Object *obj, const char *value, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+
+    if (!vu_prop_modifiable(vus, errp)) {
+        return;
+    }
+
+    if (vus->node_name) {
+        g_free(vus->node_name);
+    }
+
+    vus->node_name = g_strdup(value);
+}
+
+static char *vu_get_node_name(Object *obj, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+    return g_strdup(vus->node_name);
+}
+
+static void free_socket_addr(SocketAddress *addr)
+{
+        g_free(addr->u.q_unix.path);
+        g_free(addr);
+}
+
+static void vu_set_unix_socket(Object *obj, const char *value,
+                               Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+
+    if (!vu_prop_modifiable(vus, errp)) {
+        return;
+    }
+
+    if (vus->addr) {
+        free_socket_addr(vus->addr);
+    }
+
+    SocketAddress *addr = g_new0(SocketAddress, 1);
+    addr->type = SOCKET_ADDRESS_TYPE_UNIX;
+    addr->u.q_unix.path = g_strdup(value);
+    vus->addr = addr;
+}
+
+static char *vu_get_unix_socket(Object *obj, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+    return g_strdup(vus->addr->u.q_unix.path);
+}
+
+static bool vu_get_block_writable(Object *obj, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+    return vus->writable;
+}
+
+static void vu_set_block_writable(Object *obj, bool value, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+
+    if (!vu_prop_modifiable(vus, errp)) {
+            return;
+    }
+
+    vus->writable = value;
+}
+
+static void vu_get_blk_size(Object *obj, Visitor *v, const char *name,
+                            void *opaque, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+    uint32_t value = vus->blk_size;
+
+    visit_type_uint32(v, name, &value, errp);
+}
+
+static void vu_set_blk_size(Object *obj, Visitor *v, const char *name,
+                            void *opaque, Error **errp)
+{
+    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+
+    Error *local_err = NULL;
+    uint32_t value;
+
+    if (!vu_prop_modifiable(vus, errp)) {
+            return;
+    }
+
+    visit_type_uint32(v, name, &value, &local_err);
+    if (local_err) {
+        goto out;
+    }
+
+    check_block_size(object_get_typename(obj), name, value, &local_err);
+    if (local_err) {
+        goto out;
+    }
+
+    vus->blk_size = value;
+
+out:
+    error_propagate(errp, local_err);
+}
+
+static void vhost_user_blk_server_instance_finalize(Object *obj)
+{
+    VuBlockDev *vub = VHOST_USER_BLK_SERVER(obj);
+
+    vhost_user_blk_server_stop(vub);
+
+    /*
+     * Unlike object_property_add_str, object_class_property_add_str
+     * doesn't have a release method. Thus manual memory freeing is
+     * needed.
+     */
+    free_socket_addr(vub->addr);
+    g_free(vub->node_name);
+}
+
+static void vhost_user_blk_server_complete(UserCreatable *obj, Error **errp)
+{
+    VuBlockDev *vub = VHOST_USER_BLK_SERVER(obj);
+
+    vhost_user_blk_server_start(vub, errp);
+}
+
+static void vhost_user_blk_server_class_init(ObjectClass *klass,
+                                             void *class_data)
+{
+    UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
+    ucc->complete = vhost_user_blk_server_complete;
+
+    object_class_property_add_bool(klass, "writable",
+                                   vu_get_block_writable,
+                                   vu_set_block_writable);
+
+    object_class_property_add_str(klass, "node-name",
+                                  vu_get_node_name,
+                                  vu_set_node_name);
+
+    object_class_property_add_str(klass, "unix-socket",
+                                  vu_get_unix_socket,
+                                  vu_set_unix_socket);
+
+    object_class_property_add(klass, "logical-block-size", "uint32",
+                              vu_get_blk_size, vu_set_blk_size,
+                              NULL, NULL);
+}
+
+static const TypeInfo vhost_user_blk_server_info = {
+    .name = TYPE_VHOST_USER_BLK_SERVER,
+    .parent = TYPE_OBJECT,
+    .instance_size = sizeof(VuBlockDev),
+    .instance_finalize = vhost_user_blk_server_instance_finalize,
+    .class_init = vhost_user_blk_server_class_init,
+    .interfaces = (InterfaceInfo[]) {
+        {TYPE_USER_CREATABLE},
+        {}
+    },
+};
+
+static void vhost_user_blk_server_register_types(void)
+{
+    type_register_static(&vhost_user_blk_server_info);
+}
+
+type_init(vhost_user_blk_server_register_types)
diff --git a/softmmu/vl.c b/softmmu/vl.c
index XXXXXXX..XXXXXXX 100644
--- a/softmmu/vl.c
+++ b/softmmu/vl.c
@@ -XXX,XX +XXX,XX @@ static bool object_create_initial(const char *type, QemuOpts *opts)
     }
 #endif
 
+    /* Reason: vhost-user-blk-server property "node-name" */
+    if (g_str_equal(type, "vhost-user-blk-server")) {
+        return false;
+    }
     /*
      * Reason: filter-* property "netdev" etc.
      */
diff --git a/block/meson.build b/block/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/block/meson.build
+++ b/block/meson.build
@@ -XXX,XX +XXX,XX @@ block_ss.add(when: 'CONFIG_WIN32', if_true: files('file-win32.c', 'win32-aio.c')
 block_ss.add(when: 'CONFIG_POSIX', if_true: [files('file-posix.c'), coref, iokit])
 block_ss.add(when: 'CONFIG_LIBISCSI', if_true: files('iscsi-opts.c'))
 block_ss.add(when: 'CONFIG_LINUX', if_true: files('nvme.c'))
+block_ss.add(when: 'CONFIG_LINUX', if_true: files('export/vhost-user-blk-server.c', '../contrib/libvhost-user/libvhost-user.c'))
 block_ss.add(when: 'CONFIG_REPLICATION', if_true: files('replication.c'))
 block_ss.add(when: 'CONFIG_SHEEPDOG', if_true: files('sheepdog.c'))
 block_ss.add(when: ['CONFIG_LINUX_AIO', libaio], if_true: files('linux-aio.c'))
-- 
2.26.2

From: Coiby Xu <coiby.xu@gmail.com>

Suggested-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Coiby Xu <coiby.xu@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20200918080912.321299-8-coiby.xu@gmail.com
[Removed reference to vhost-user-blk-test.c, it will be sent in a
separate pull request.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 MAINTAINERS | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index XXXXXXX..XXXXXXX 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -XXX,XX +XXX,XX @@ L: qemu-block@nongnu.org
 S: Supported
 F: tests/image-fuzzer/
 
+Vhost-user block device backend server
+M: Coiby Xu <Coiby.Xu@gmail.com>
+S: Maintained
+F: block/export/vhost-user-blk-server.c
+F: util/vhost-user-server.c
+F: tests/qtest/libqos/vhost-user-blk.c
+
 Replication
 M: Wen Congyang <wencongyang2@huawei.com>
 M: Xie Changlong <xiechanglong.d@gmail.com>
-- 
2.26.2

Explicitly deleting watches is not necessary since libvhost-user calls
remove_watch() during vu_deinit(). Add an assertion to check this
though.

diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@ static void close_client(VuServer *server)
     /* When this is set vu_client_trip will stop new processing vhost-user message */
     server->sioc = NULL;
 
-    VuFdWatch *vu_fd_watch, *next;
-    QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
-        aio_set_fd_handler(server->ioc->ctx, vu_fd_watch->fd, true, NULL,
-                           NULL, NULL, NULL);
-    }
-
-    while (!QTAILQ_EMPTY(&server->vu_fd_watches)) {
-        QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
-            if (!vu_fd_watch->processing) {
-                QTAILQ_REMOVE(&server->vu_fd_watches, vu_fd_watch, next);
-                g_free(vu_fd_watch);
-            }
-        }
-    }
-
     while (server->processing_msg) {
         if (server->ioc->read_coroutine) {
             server->ioc->read_coroutine = NULL;
@@ -XXX,XX +XXX,XX @@ static void close_client(VuServer *server)
     }
 
     vu_deinit(&server->vu_dev);
+
+    /* vu_deinit() should have called remove_watch() */
+    assert(QTAILQ_EMPTY(&server->vu_fd_watches));
+
     object_unref(OBJECT(sioc));
     object_unref(OBJECT(server->ioc));
 }
-- 
2.26.2

Only one struct is needed per request. Drop req_data and the separate
VuBlockReq instance. Instead let vu_queue_pop() allocate everything at
once.

This fixes the req_data memory leak in vu_block_virtio_process_req().

The device panic notifier callback is not used. Drop it.

diff --git a/util/vhost-user-server.h b/util/vhost-user-server.h
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.h
+++ b/util/vhost-user-server.h
@@ -XXX,XX +XXX,XX @@ typedef struct VuFdWatch {
 } VuFdWatch;
 
 typedef struct VuServer VuServer;
-typedef void DevicePanicNotifierFn(VuServer *server);
 
 struct VuServer {
     QIONetListener *listener;
     AioContext *ctx;
-    DevicePanicNotifierFn *device_panic_notifier;
     int max_queues;
     const VuDevIface *vu_iface;
     VuDev vu_dev;
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
                              SocketAddress *unix_socket,
                              AioContext *ctx,
                              uint16_t max_queues,
-                             DevicePanicNotifierFn *device_panic_notifier,
                              const VuDevIface *vu_iface,
                              Error **errp);
 
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.c
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@ static void vhost_user_blk_server_start(VuBlockDev *vu_block_device,
     ctx = bdrv_get_aio_context(blk_bs(vu_block_device->backend));
 
     if (!vhost_user_server_start(&vu_block_device->vu_server, addr, ctx,
-                                 VHOST_USER_BLK_MAX_QUEUES,
-                                 NULL, &vu_block_iface,
+                                 VHOST_USER_BLK_MAX_QUEUES, &vu_block_iface,
                                  errp)) {
         goto error;
     }
diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@ static void panic_cb(VuDev *vu_dev, const char *buf)
         close_client(server);
     }
 
-    if (server->device_panic_notifier) {
-        server->device_panic_notifier(server);
-    }
-
     /*
      * Set the callback function for network listener so another
      * vhost-user client can connect to this server
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
                              SocketAddress *socket_addr,
                              AioContext *ctx,
                              uint16_t max_queues,
-                             DevicePanicNotifierFn *device_panic_notifier,
                              const VuDevIface *vu_iface,
                              Error **errp)
 {
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
         .vu_iface              = vu_iface,
         .max_queues            = max_queues,
         .ctx                   = ctx,
-        .device_panic_notifier = device_panic_notifier,
     };
 
     qio_net_listener_set_name(server->listener, "vhost-user-backend-listener");
-- 
2.26.2

fds[] is leaked when qio_channel_readv_full() fails.

Use vmsg->fds[] instead of keeping a local fds[] array. Then we can
reuse goto fail to clean up fds. vmsg->fd_num must be zeroed before the
loop to make this safe.

diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@ vu_message_read(VuDev *vu_dev, int conn_fd, VhostUserMsg *vmsg)
     };
     int rc, read_bytes = 0;
     Error *local_err = NULL;
-    /*
-     * Store fds/nfds returned from qio_channel_readv_full into
-     * temporary variables.
-     *
-     * VhostUserMsg is a packed structure, gcc will complain about passing
-     * pointer to a packed structure member if we pass &VhostUserMsg.fd_num
-     * and &VhostUserMsg.fds directly when calling qio_channel_readv_full,
-     * thus two temporary variables nfds and fds are used here.
-     */
-    size_t nfds = 0, nfds_t = 0;
     const size_t max_fds = G_N_ELEMENTS(vmsg->fds);
-    int *fds_t = NULL;
     VuServer *server = container_of(vu_dev, VuServer, vu_dev);
     QIOChannel *ioc = server->ioc;
 
+    vmsg->fd_num = 0;
     if (!ioc) {
         error_report_err(local_err);
         goto fail;
@@ -XXX,XX +XXX,XX @@ vu_message_read(VuDev *vu_dev, int conn_fd, VhostUserMsg *vmsg)
 
     assert(qemu_in_coroutine());
     do {
+        size_t nfds = 0;
+        int *fds = NULL;
+
         /*
          * qio_channel_readv_full may have short reads, keeping calling it
          * until getting VHOST_USER_HDR_SIZE or 0 bytes in total
          */
-        rc = qio_channel_readv_full(ioc, &iov, 1, &fds_t, &nfds_t, &local_err);
+        rc = qio_channel_readv_full(ioc, &iov, 1, &fds, &nfds, &local_err);
         if (rc < 0) {
             if (rc == QIO_CHANNEL_ERR_BLOCK) {
+                assert(local_err == NULL);
                 qio_channel_yield(ioc, G_IO_IN);
                 continue;
             } else {
                 error_report_err(local_err);
-                return false;
+                goto fail;
             }
         }
-        read_bytes += rc;
-        if (nfds_t > 0) {
-            if (nfds + nfds_t > max_fds) {
+
+        if (nfds > 0) {
+            if (vmsg->fd_num + nfds > max_fds) {
                 error_report("A maximum of %zu fds are allowed, "
                              "however got %zu fds now",
-                             max_fds, nfds + nfds_t);
+                             max_fds, vmsg->fd_num + nfds);
+                g_free(fds);
                 goto fail;
             }
-            memcpy(vmsg->fds + nfds, fds_t,
-                   nfds_t *sizeof(vmsg->fds[0]));
-            nfds += nfds_t;
-            g_free(fds_t);
+            memcpy(vmsg->fds + vmsg->fd_num, fds, nfds * sizeof(vmsg->fds[0]));
+            vmsg->fd_num += nfds;
+            g_free(fds);
         }
-        if (read_bytes == VHOST_USER_HDR_SIZE || rc == 0) {
-            break;
+
+        if (rc == 0) { /* socket closed */
+            goto fail;
         }
-        iov.iov_base = (char *)vmsg + read_bytes;
-        iov.iov_len = VHOST_USER_HDR_SIZE - read_bytes;
-    } while (true);
 
-    vmsg->fd_num = nfds;
+        iov.iov_base += rc;
+        iov.iov_len -= rc;
+        read_bytes += rc;
+    } while (read_bytes != VHOST_USER_HDR_SIZE);
+
     /* qio_channel_readv_full will make socket fds blocking, unblock them */
     vmsg_unblock_fds(vmsg);
     if (vmsg->size > sizeof(vmsg->payload)) {
-- 
2.26.2

The vu_client_trip() coroutine is leaked during AioContext switching. It
is also unsafe to destroy the vu_dev in panic_cb() since its callers
still access it in some cases.

Rework the lifecycle to solve these safety issues.

diff --git a/util/vhost-user-server.h b/util/vhost-user-server.h
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.h
+++ b/util/vhost-user-server.h
@@ -XXX,XX +XXX,XX @@
 #include "qapi/error.h"
 #include "standard-headers/linux/virtio_blk.h"
 
+/* A kick fd that we monitor on behalf of libvhost-user */
 typedef struct VuFdWatch {
     VuDev *vu_dev;
     int fd; /*kick fd*/
     void *pvt;
     vu_watch_cb cb;
-    bool processing;
     QTAILQ_ENTRY(VuFdWatch) next;
 } VuFdWatch;
 
-typedef struct VuServer VuServer;
-
-struct VuServer {
+/**
+ * VuServer:
+ * A vhost-user server instance with user-defined VuDevIface callbacks.
+ * Vhost-user device backends can be implemented using VuServer. VuDevIface
+ * callbacks and virtqueue kicks run in the given AioContext.
+ */
+typedef struct {
     QIONetListener *listener;
+    QEMUBH *restart_listener_bh;
     AioContext *ctx;
     int max_queues;
     const VuDevIface *vu_iface;
+
+    /* Protected by ctx lock */
     VuDev vu_dev;
     QIOChannel *ioc; /* The I/O channel with the client */
     QIOChannelSocket *sioc; /* The underlying data channel with the client */
-    /* IOChannel for fd provided via VHOST_USER_SET_SLAVE_REQ_FD */
-    QIOChannel *ioc_slave;
-    QIOChannelSocket *sioc_slave;
-    Coroutine *co_trip; /* coroutine for processing VhostUserMsg */
     QTAILQ_HEAD(, VuFdWatch) vu_fd_watches;
-    /* restart coroutine co_trip if AIOContext is changed */
-    bool aio_context_changed;
-    bool processing_msg;
-};
+
+    Coroutine *co_trip; /* coroutine for processing VhostUserMsg */
+} VuServer;
 
 bool vhost_user_server_start(VuServer *server,
                              SocketAddress *unix_socket,
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
 
 void vhost_user_server_stop(VuServer *server);
 
-void vhost_user_server_set_aio_context(VuServer *server, AioContext *ctx);
+void vhost_user_server_attach_aio_context(VuServer *server, AioContext *ctx);
+void vhost_user_server_detach_aio_context(VuServer *server);
 
 #endif /* VHOST_USER_SERVER_H */
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.c
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@ static const VuDevIface vu_block_iface = {
 static void blk_aio_attached(AioContext *ctx, void *opaque)
 {
     VuBlockDev *vub_dev = opaque;
-    aio_context_acquire(ctx);
-    vhost_user_server_set_aio_context(&vub_dev->vu_server, ctx);
-    aio_context_release(ctx);
+    vhost_user_server_attach_aio_context(&vub_dev->vu_server, ctx);
 }
 
 static void blk_aio_detach(void *opaque)
 {
     VuBlockDev *vub_dev = opaque;
-    AioContext *ctx = vub_dev->vu_server.ctx;
-    aio_context_acquire(ctx);
-    vhost_user_server_set_aio_context(&vub_dev->vu_server, NULL);
-    aio_context_release(ctx);
+    vhost_user_server_detach_aio_context(&vub_dev->vu_server);
 }
 
 static void
diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@
  */
 #include "qemu/osdep.h"
 #include "qemu/main-loop.h"
+#include "block/aio-wait.h"
 #include "vhost-user-server.h"
 
+/*
+ * Theory of operation:
+ *
+ * VuServer is started and stopped by vhost_user_server_start() and
+ * vhost_user_server_stop() from the main loop thread. Starting the server
+ * opens a vhost-user UNIX domain socket and listens for incoming connections.
+ * Only one connection is allowed at a time.
+ *
+ * The connection is handled by the vu_client_trip() coroutine in the
+ * VuServer->ctx AioContext. The coroutine consists of a vu_dispatch() loop
+ * where libvhost-user calls vu_message_read() to receive the next vhost-user
+ * protocol messages over the UNIX domain socket.
+ *
+ * When virtqueues are set up libvhost-user calls set_watch() to monitor kick
+ * fds. These fds are also handled in the VuServer->ctx AioContext.
+ *
+ * Both vu_client_trip() and kick fd monitoring can be stopped by shutting down
+ * the socket connection. Shutting down the socket connection causes
+ * vu_message_read() to fail since no more data can be received from the socket.
+ * After vu_dispatch() fails, vu_client_trip() calls vu_deinit() to stop
+ * libvhost-user before terminating the coroutine. vu_deinit() calls
+ * remove_watch() to stop monitoring kick fds and this stops virtqueue
+ * processing.
+ *
+ * When vu_client_trip() has finished cleaning up it schedules a BH in the main
+ * loop thread to accept the next client connection.
+ *
+ * When libvhost-user detects an error it calls panic_cb() and sets the
+ * dev->broken flag. Both vu_client_trip() and kick fd processing stop when
+ * the dev->broken flag is set.
+ *
+ * It is possible to switch AioContexts using
+ * vhost_user_server_detach_aio_context() and
+ * vhost_user_server_attach_aio_context(). They stop monitoring fds in the old
+ * AioContext and resume monitoring in the new AioContext. The vu_client_trip()
+ * coroutine remains in a yielded state during the switch. This is made
+ * possible by QIOChannel's support for spurious coroutine re-entry in
+ * qio_channel_yield(). The coroutine will restart I/O when re-entered from the
+ * new AioContext.
+ */
+
 static void vmsg_close_fds(VhostUserMsg *vmsg)
 {
     int i;
@@ -XXX,XX +XXX,XX @@ static void vmsg_unblock_fds(VhostUserMsg *vmsg)
     }
 }
 
-static void vu_accept(QIONetListener *listener, QIOChannelSocket *sioc,
-                      gpointer opaque);
-
-static void close_client(VuServer *server)
-{
-    /*
-     * Before closing the client
-     *
-     * 1. Let vu_client_trip stop processing new vhost-user msg
-     *
-     * 2. remove kick_handler
-     *
-     * 3. wait for the kick handler to be finished
-     *
-     * 4. wait for the current vhost-user msg to be finished processing
-     */
-
-    QIOChannelSocket *sioc = server->sioc;
-    /* When this is set vu_client_trip will stop new processing vhost-user message */
-    server->sioc = NULL;
-
-    while (server->processing_msg) {
-        if (server->ioc->read_coroutine) {
-            server->ioc->read_coroutine = NULL;
-            qio_channel_set_aio_fd_handler(server->ioc, server->ioc->ctx, NULL,
-                                           NULL, server->ioc);
-            server->processing_msg = false;
-        }
-    }
-
-    vu_deinit(&server->vu_dev);
-
-    /* vu_deinit() should have called remove_watch() */
-    assert(QTAILQ_EMPTY(&server->vu_fd_watches));
-
-    object_unref(OBJECT(sioc));
-    object_unref(OBJECT(server->ioc));
-}
-
 static void panic_cb(VuDev *vu_dev, const char *buf)
 {
-    VuServer *server = container_of(vu_dev, VuServer, vu_dev);
-
-    /* avoid while loop in close_client */
-    server->processing_msg = false;
-
-    if (buf) {
-        error_report("vu_panic: %s", buf);
-    }
-
-    if (server->sioc) {
-        close_client(server);
-    }
-
-    /*
-     * Set the callback function for network listener so another
-     * vhost-user client can connect to this server
-     */
-    qio_net_listener_set_client_func(server->listener,
-                                     vu_accept,
-                                     server,
-                                     NULL);
+    error_report("vu_panic: %s", buf);
 }
 
 static bool coroutine_fn
@@ -XXX,XX +XXX,XX @@ fail:
     return false;
 }
 
-
-static void vu_client_start(VuServer *server);
 static coroutine_fn void vu_client_trip(void *opaque)
 {
     VuServer *server = opaque;
+    VuDev *vu_dev = &server->vu_dev;
 
-    while (!server->aio_context_changed && server->sioc) {
-        server->processing_msg = true;
-        vu_dispatch(&server->vu_dev);
-        server->processing_msg = false;
+    while (!vu_dev->broken && vu_dispatch(vu_dev)) {
+        /* Keep running */
     }
 
-    if (server->aio_context_changed && server->sioc) {
-        server->aio_context_changed = false;
-        vu_client_start(server);
-    }
-}
+    vu_deinit(vu_dev);
+
+    /* vu_deinit() should have called remove_watch() */
+    assert(QTAILQ_EMPTY(&server->vu_fd_watches));
+
+    object_unref(OBJECT(server->sioc));
+    server->sioc = NULL;
 
-static void vu_client_start(VuServer *server)
-{
-    server->co_trip = qemu_coroutine_create(vu_client_trip, server);
-    aio_co_enter(server->ctx, server->co_trip);
+    object_unref(OBJECT(server->ioc));
+    server->ioc = NULL;
+
+    server->co_trip = NULL;
+    if (server->restart_listener_bh) {
+        qemu_bh_schedule(server->restart_listener_bh);
+    }
+    aio_wait_kick();
 }
 
 /*
@@ -XXX,XX +XXX,XX @@ static void vu_client_start(VuServer *server)
 static void kick_handler(void *opaque)
 {
     VuFdWatch *vu_fd_watch = opaque;
-    vu_fd_watch->processing = true;
-    vu_fd_watch->cb(vu_fd_watch->vu_dev, 0, vu_fd_watch->pvt);
-    vu_fd_watch->processing = false;
+    VuDev *vu_dev = vu_fd_watch->vu_dev;
+
+    vu_fd_watch->cb(vu_dev, 0, vu_fd_watch->pvt);
+
+    /* Stop vu_client_trip() if an error occurred in vu_fd_watch->cb() */
+    if (vu_dev->broken) {
+        VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+
+        qio_channel_shutdown(server->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
+    }
 }
 
-
 static VuFdWatch *find_vu_fd_watch(VuServer *server, int fd)
 {
 
@@ -XXX,XX +XXX,XX @@ static void vu_accept(QIONetListener *listener, QIOChannelSocket *sioc,
     qio_channel_set_name(QIO_CHANNEL(sioc), "vhost-user client");
     server->ioc = QIO_CHANNEL(sioc);
     object_ref(OBJECT(server->ioc));
-    qio_channel_attach_aio_context(server->ioc, server->ctx);
+
+    /* TODO vu_message_write() spins if non-blocking! */
     qio_channel_set_blocking(server->ioc, false, NULL);
-    vu_client_start(server);
+
+    server->co_trip = qemu_coroutine_create(vu_client_trip, server);
+
+    aio_context_acquire(server->ctx);
+    vhost_user_server_attach_aio_context(server, server->ctx);
+    aio_context_release(server->ctx);
 }
 
-
 void vhost_user_server_stop(VuServer *server)
 {
+    aio_context_acquire(server->ctx);
+
+    qemu_bh_delete(server->restart_listener_bh);
+    server->restart_listener_bh = NULL;
+
     if (server->sioc) {
-        close_client(server);
+        VuFdWatch *vu_fd_watch;
+
+        QTAILQ_FOREACH(vu_fd_watch, &server->vu_fd_watches, next) {
+            aio_set_fd_handler(server->ctx, vu_fd_watch->fd, true,
+                               NULL, NULL, NULL, vu_fd_watch);
+        }
+
+        qio_channel_shutdown(server->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
+
+        AIO_WAIT_WHILE(server->ctx, server->co_trip);
     }
 
+    aio_context_release(server->ctx);
+
     if (server->listener) {
         qio_net_listener_disconnect(server->listener);
         object_unref(OBJECT(server->listener));
     }
+}
+
+/*
+ * Allow the next client to connect to the server. Called from a BH in the main
+ * loop.
+ */
+static void restart_listener_bh(void *opaque)
+{
+    VuServer *server = opaque;
 
+    qio_net_listener_set_client_func(server->listener, vu_accept, server,
+                                     NULL);
 }
 
-void vhost_user_server_set_aio_context(VuServer *server, AioContext *ctx)
+/* Called with ctx acquired */
+void vhost_user_server_attach_aio_context(VuServer *server, AioContext *ctx)
 {
-    VuFdWatch *vu_fd_watch, *next;
-    void *opaque = NULL;
-    IOHandler *io_read = NULL;
-    bool attach;
+    VuFdWatch *vu_fd_watch;
 
-    server->ctx = ctx ? ctx : qemu_get_aio_context();
+    server->ctx = ctx;
 
     if (!server->sioc) {
-        /* not yet serving any client*/
         return;
     }
 
-    if (ctx) {
-        qio_channel_attach_aio_context(server->ioc, ctx);
-        server->aio_context_changed = true;
-        io_read = kick_handler;
-        attach = true;
-    } else {
+    qio_channel_attach_aio_context(server->ioc, ctx);
+
+    QTAILQ_FOREACH(vu_fd_watch, &server->vu_fd_watches, next) {
+        aio_set_fd_handler(ctx, vu_fd_watch->fd, true, kick_handler, NULL,
+                           NULL, vu_fd_watch);
+    }
+
+    aio_co_schedule(ctx, server->co_trip);
+}
+
+/* Called with server->ctx acquired */
+void vhost_user_server_detach_aio_context(VuServer *server)
+{
+    if (server->sioc) {
+        VuFdWatch *vu_fd_watch;
+
+        QTAILQ_FOREACH(vu_fd_watch, &server->vu_fd_watches, next) {
+            aio_set_fd_handler(server->ctx, vu_fd_watch->fd, true,
+                               NULL, NULL, NULL, vu_fd_watch);
+        }
+
         qio_channel_detach_aio_context(server->ioc);
-        /* server->ioc->ctx keeps the old AioConext */
-        ctx = server->ioc->ctx;
-        attach = false;
     }
 
-    QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
-        if (vu_fd_watch->cb) {
-            opaque = attach ? vu_fd_watch : NULL;
-            aio_set_fd_handler(ctx, vu_fd_watch->fd, true,
-                               io_read, NULL, NULL,
-                               opaque);
-        }
-    }
+    server->ctx = NULL;
 }
 
-
 bool vhost_user_server_start(VuServer *server,
                              SocketAddress *socket_addr,
                              AioContext *ctx,
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
                              const VuDevIface *vu_iface,
                              Error **errp)
 {
+    QEMUBH *bh;
     QIONetListener *listener = qio_net_listener_new();
     if (qio_net_listener_open_sync(listener, socket_addr, 1,
                                    errp) < 0) {
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
         return false;
     }
 
+    bh = qemu_bh_new(restart_listener_bh, server);
+
     /* zero out unspecified fields */
     *server = (VuServer) {
         .listener              = listener,
+        .restart_listener_bh   = bh,
         .vu_iface              = vu_iface,
         .max_queues            = max_queues,
         .ctx                   = ctx,
-- 
2.26.2

Propagate the flush return value since errors are possible.

Use the new QAPI block exports API instead of defining our own QOM
objects.

This is a large change because the lifecycle of VuBlockDev needs to
follow BlockExportDriver. QOM properties are replaced by QAPI options
objects.

VuBlockDev is renamed VuBlkExport and contains a BlockExport field.
Several fields can be dropped since BlockExport already has equivalents.

The new command-line syntax is:

$ qemu-storage-daemon \
      --blockdev file,node-name=drive0,filename=test.img \
      --export vhost-user-blk,node-name=drive0,id=export0,unix-socket=/tmp/vhost-user-blk.sock

Note that unix-socket is optional because we may wish to accept chardevs
too in the future.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20200924151549.913737-12-stefanha@redhat.com
[Skip test on big-endian host architectures because this device doesn't
support them yet (as already mentioned in a code comment).
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 qapi/block-export.json               |  21 +-
 block/export/vhost-user-blk-server.h |  23 +-
 block/export/export.c                |   6 +
 block/export/vhost-user-blk-server.c | 452 +++++++--------------------
 util/vhost-user-server.c             |  10 +-
 block/export/meson.build             |   1 +
 block/meson.build                    |   1 -
 7 files changed, 156 insertions(+), 358 deletions(-)

diff --git a/qapi/block-export.json b/qapi/block-export.json
index XXXXXXX..XXXXXXX 100644
--- a/qapi/block-export.json
+++ b/qapi/block-export.json
@@ -XXX,XX +XXX,XX @@
   'data': { '*name': 'str', '*description': 'str',
             '*bitmap': 'str' } }
 
+##
+# @BlockExportOptionsVhostUserBlk:
+#
+# A vhost-user-blk block export.
+#
+# @addr: The vhost-user socket on which to listen. Both 'unix' and 'fd'
+#        SocketAddress types are supported. Passed fds must be UNIX domain
+#        sockets.
+# @logical-block-size: Logical block size in bytes. Defaults to 512 bytes.
+#
+# Since: 5.2
+##
+{ 'struct': 'BlockExportOptionsVhostUserBlk',
+  'data': { 'addr': 'SocketAddress', '*logical-block-size': 'size' } }
+
 ##
 # @NbdServerAddOptions:
 #
@@ -XXX,XX +XXX,XX @@
 # An enumeration of block export types
 #
 # @nbd: NBD export
+# @vhost-user-blk: vhost-user-blk export (since 5.2)
 #
 # Since: 4.2
 ##
 { 'enum': 'BlockExportType',
-  'data': [ 'nbd' ] }
+  'data': [ 'nbd', 'vhost-user-blk' ] }
 
 ##
 # @BlockExportOptions:
@@ -XXX,XX +XXX,XX @@
             '*writethrough': 'bool' },
   'discriminator': 'type',
   'data': {
-      'nbd': 'BlockExportOptionsNbd'
+      'nbd': 'BlockExportOptionsNbd',
+      'vhost-user-blk': 'BlockExportOptionsVhostUserBlk'
    } }
 
 ##
diff --git a/block/export/vhost-user-blk-server.h b/block/export/vhost-user-blk-server.h
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.h
+++ b/block/export/vhost-user-blk-server.h
@@ -XXX,XX +XXX,XX @@
 
 #ifndef VHOST_USER_BLK_SERVER_H
 #define VHOST_USER_BLK_SERVER_H
-#include "util/vhost-user-server.h"
 
-typedef struct VuBlockDev VuBlockDev;
-#define TYPE_VHOST_USER_BLK_SERVER "vhost-user-blk-server"
-#define VHOST_USER_BLK_SERVER(obj) \
-   OBJECT_CHECK(VuBlockDev, obj, TYPE_VHOST_USER_BLK_SERVER)
+#include "block/export.h"
 
-/* vhost user block device */
-struct VuBlockDev {
-    Object parent_obj;
-    char *node_name;
-    SocketAddress *addr;
-    AioContext *ctx;
-    VuServer vu_server;
-    bool running;
-    uint32_t blk_size;
-    BlockBackend *backend;
-    QIOChannelSocket *sioc;
-    QTAILQ_ENTRY(VuBlockDev) next;
-    struct virtio_blk_config blkcfg;
-    bool writable;
-};
+/* For block/export/export.c */
+extern const BlockExportDriver blk_exp_vhost_user_blk;
 
 #endif /* VHOST_USER_BLK_SERVER_H */
diff --git a/block/export/export.c b/block/export/export.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/export.c
+++ b/block/export/export.c
@@ -XXX,XX +XXX,XX @@
 #include "sysemu/block-backend.h"
 #include "block/export.h"
 #include "block/nbd.h"
+#if CONFIG_LINUX
+#include "block/export/vhost-user-blk-server.h"
+#endif
 #include "qapi/error.h"
 #include "qapi/qapi-commands-block-export.h"
 #include "qapi/qapi-events-block-export.h"
@@ -XXX,XX +XXX,XX @@
 
 static const BlockExportDriver *blk_exp_drivers[] = {
     &blk_exp_nbd,
+#if CONFIG_LINUX
+    &blk_exp_vhost_user_blk,
+#endif
 };
 
 /* Only accessed from the main thread */
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.c
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@
  */
 #include "qemu/osdep.h"
 #include "block/block.h"
+#include "contrib/libvhost-user/libvhost-user.h"
+#include "standard-headers/linux/virtio_blk.h"
+#include "util/vhost-user-server.h"
 #include "vhost-user-blk-server.h"
 #include "qapi/error.h"
 #include "qom/object_interfaces.h"
@@ -XXX,XX +XXX,XX @@ struct virtio_blk_inhdr {
     unsigned char status;
 };
 
-typedef struct VuBlockReq {
+typedef struct VuBlkReq {
     VuVirtqElement elem;
     int64_t sector_num;
     size_t size;
@@ -XXX,XX +XXX,XX @@ typedef struct VuBlockReq {
     struct virtio_blk_outhdr out;
     VuServer *server;
     struct VuVirtq *vq;
-} VuBlockReq;
+} VuBlkReq;
 
-static void vu_block_req_complete(VuBlockReq *req)
+/* vhost user block device */
+typedef struct {
+    BlockExport export;
+    VuServer vu_server;
+    uint32_t blk_size;
+    QIOChannelSocket *sioc;
+    struct virtio_blk_config blkcfg;
+    bool writable;
+} VuBlkExport;
+
+static void vu_blk_req_complete(VuBlkReq *req)
 {
     VuDev *vu_dev = &req->server->vu_dev;
 
@@ -XXX,XX +XXX,XX @@ static void vu_block_req_complete(VuBlockReq *req)
     free(req);
 }
 
-static VuBlockDev *get_vu_block_device_by_server(VuServer *server)
-{
-    return container_of(server, VuBlockDev, vu_server);
-}
-
 static int coroutine_fn
-vu_block_discard_write_zeroes(VuBlockReq *req, struct iovec *iov,
-                              uint32_t iovcnt, uint32_t type)
+vu_blk_discard_write_zeroes(BlockBackend *blk, struct iovec *iov,
+                            uint32_t iovcnt, uint32_t type)
 {
     struct virtio_blk_discard_write_zeroes desc;
     ssize_t size = iov_to_buf(iov, iovcnt, 0, &desc, sizeof(desc));
@@ -XXX,XX +XXX,XX @@ vu_block_discard_write_zeroes(VuBlockReq *req, struct iovec *iov,
         return -EINVAL;
     }
 
-    VuBlockDev *vdev_blk = get_vu_block_device_by_server(req->server);
     uint64_t range[2] = { le64_to_cpu(desc.sector) << 9,
                           le32_to_cpu(desc.num_sectors) << 9 };
     if (type == VIRTIO_BLK_T_DISCARD) {
-        if (blk_co_pdiscard(vdev_blk->backend, range[0], range[1]) == 0) {
+        if (blk_co_pdiscard(blk, range[0], range[1]) == 0) {
             return 0;
         }
     } else if (type == VIRTIO_BLK_T_WRITE_ZEROES) {
-        if (blk_co_pwrite_zeroes(vdev_blk->backend,
-                                 range[0], range[1], 0) == 0) {
+        if (blk_co_pwrite_zeroes(blk, range[0], range[1], 0) == 0) {
             return 0;
         }
     }
@@ -XXX,XX +XXX,XX @@ vu_block_discard_write_zeroes(VuBlockReq *req, struct iovec *iov,
     return -EINVAL;
 }
 
-static int coroutine_fn vu_block_flush(VuBlockReq *req)
+static void coroutine_fn vu_blk_virtio_process_req(void *opaque)
 {
-    VuBlockDev *vdev_blk = get_vu_block_device_by_server(req->server);
-    BlockBackend *backend = vdev_blk->backend;
-    return blk_co_flush(backend);
-}
-
-static void coroutine_fn vu_block_virtio_process_req(void *opaque)
-{
-    VuBlockReq *req = opaque;
+    VuBlkReq *req = opaque;
     VuServer *server = req->server;
     VuVirtqElement *elem = &req->elem;
     uint32_t type;
 
-    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
-    BlockBackend *backend = vdev_blk->backend;
+    VuBlkExport *vexp = container_of(server, VuBlkExport, vu_server);
+    BlockBackend *blk = vexp->export.blk;
 
     struct iovec *in_iov = elem->in_sg;
     struct iovec *out_iov = elem->out_sg;
@@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
         bool is_write = type & VIRTIO_BLK_T_OUT;
         req->sector_num = le64_to_cpu(req->out.sector);
 
-        int64_t offset = req->sector_num * vdev_blk->blk_size;
+        if (is_write && !vexp->writable) {
+            req->in->status = VIRTIO_BLK_S_IOERR;
+            break;
+        }
+
+        int64_t offset = req->sector_num * vexp->blk_size;
         QEMUIOVector qiov;
         if (is_write) {
             qemu_iovec_init_external(&qiov, out_iov, out_num);
-            ret = blk_co_pwritev(backend, offset, qiov.size,
-                                 &qiov, 0);
+            ret = blk_co_pwritev(blk, offset, qiov.size, &qiov, 0);
         } else {
             qemu_iovec_init_external(&qiov, in_iov, in_num);
-            ret = blk_co_preadv(backend, offset, qiov.size,
-                                &qiov, 0);
+            ret = blk_co_preadv(blk, offset, qiov.size, &qiov, 0);
         }
         if (ret >= 0) {
             req->in->status = VIRTIO_BLK_S_OK;
@@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
         break;
     }
     case VIRTIO_BLK_T_FLUSH:
-        if (vu_block_flush(req) == 0) {
+        if (blk_co_flush(blk) == 0) {
             req->in->status = VIRTIO_BLK_S_OK;
         } else {
             req->in->status = VIRTIO_BLK_S_IOERR;
@@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
     case VIRTIO_BLK_T_DISCARD:
     case VIRTIO_BLK_T_WRITE_ZEROES: {
         int rc;
-        rc = vu_block_discard_write_zeroes(req, &elem->out_sg[1],
-                                           out_num, type);
+
+        if (!vexp->writable) {
+            req->in->status = VIRTIO_BLK_S_IOERR;
+            break;
+        }
+
+        rc = vu_blk_discard_write_zeroes(blk, &elem->out_sg[1], out_num, type);
         if (rc == 0) {
             req->in->status = VIRTIO_BLK_S_OK;
         } else {
@@ -XXX,XX +XXX,XX @@ static void coroutine_fn vu_block_virtio_process_req(void *opaque)
         break;
     }
 
-    vu_block_req_complete(req);
+    vu_blk_req_complete(req);
     return;
 
 err:
-    free(elem);
+    free(req);
 }
 
-static void vu_block_process_vq(VuDev *vu_dev, int idx)
+static void vu_blk_process_vq(VuDev *vu_dev, int idx)
 {
     VuServer *server = container_of(vu_dev, VuServer, vu_dev);
     VuVirtq *vq = vu_get_queue(vu_dev, idx);
 
     while (1) {
-        VuBlockReq *req;
+        VuBlkReq *req;
 
-        req = vu_queue_pop(vu_dev, vq, sizeof(VuBlockReq));
+        req = vu_queue_pop(vu_dev, vq, sizeof(VuBlkReq));
         if (!req) {
             break;
         }
@@ -XXX,XX +XXX,XX @@ static void vu_block_process_vq(VuDev *vu_dev, int idx)
         req->vq = vq;
 
         Coroutine *co =
-            qemu_coroutine_create(vu_block_virtio_process_req, req);
+            qemu_coroutine_create(vu_blk_virtio_process_req, req);
         qemu_coroutine_enter(co);
     }
 }
 
-static void vu_block_queue_set_started(VuDev *vu_dev, int idx, bool started)
+static void vu_blk_queue_set_started(VuDev *vu_dev, int idx, bool started)
 {
     VuVirtq *vq;
 
     assert(vu_dev);
 
     vq = vu_get_queue(vu_dev, idx);
-    vu_set_queue_handler(vu_dev, vq, started ? vu_block_process_vq : NULL);
+    vu_set_queue_handler(vu_dev, vq, started ? vu_blk_process_vq : NULL);
 }
 
-static uint64_t vu_block_get_features(VuDev *dev)
+static uint64_t vu_blk_get_features(VuDev *dev)
 {
     uint64_t features;
     VuServer *server = container_of(dev, VuServer, vu_dev);
-    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+    VuBlkExport *vexp = container_of(server, VuBlkExport, vu_server);
     features = 1ull << VIRTIO_BLK_F_SIZE_MAX |
                1ull << VIRTIO_BLK_F_SEG_MAX |
                1ull << VIRTIO_BLK_F_TOPOLOGY |
@@ -XXX,XX +XXX,XX @@ static uint64_t vu_block_get_features(VuDev *dev)
                1ull << VIRTIO_RING_F_EVENT_IDX |
                1ull << VHOST_USER_F_PROTOCOL_FEATURES;
 
-    if (!vdev_blk->writable) {
+    if (!vexp->writable) {
         features |= 1ull << VIRTIO_BLK_F_RO;
     }
 
     return features;
 }
 
-static uint64_t vu_block_get_protocol_features(VuDev *dev)
+static uint64_t vu_blk_get_protocol_features(VuDev *dev)
 {
     return 1ull << VHOST_USER_PROTOCOL_F_CONFIG |
            1ull << VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD;
 }
 
 static int
-vu_block_get_config(VuDev *vu_dev, uint8_t *config, uint32_t len)
+vu_blk_get_config(VuDev *vu_dev, uint8_t *config, uint32_t len)
 {
+    /* TODO blkcfg must be little-endian for VIRTIO 1.0 */
     VuServer *server = container_of(vu_dev, VuServer, vu_dev);
-    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
-    memcpy(config, &vdev_blk->blkcfg, len);
-
+    VuBlkExport *vexp = container_of(server, VuBlkExport, vu_server);
+    memcpy(config, &vexp->blkcfg, len);
     return 0;
 }
 
 static int
-vu_block_set_config(VuDev *vu_dev, const uint8_t *data,
+vu_blk_set_config(VuDev *vu_dev, const uint8_t *data,
                     uint32_t offset, uint32_t size, uint32_t flags)
 {
     VuServer *server = container_of(vu_dev, VuServer, vu_dev);
-    VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+    VuBlkExport *vexp = container_of(server, VuBlkExport, vu_server);
     uint8_t wce;
 
     /* don't support live migration */
@@ -XXX,XX +XXX,XX @@ vu_block_set_config(VuDev *vu_dev, const uint8_t *data,
     }
 
     wce = *data;
-    vdev_blk->blkcfg.wce = wce;
-    blk_set_enable_write_cache(vdev_blk->backend, wce);
+    vexp->blkcfg.wce = wce;
+    blk_set_enable_write_cache(vexp->export.blk, wce);
     return 0;
 }
 
@@ -XXX,XX +XXX,XX @@ vu_block_set_config(VuDev *vu_dev, const uint8_t *data,
  * of vu_process_message.
  *
  */
-static int vu_block_process_msg(VuDev *dev, VhostUserMsg *vmsg, int *do_reply)
+static int vu_blk_process_msg(VuDev *dev, VhostUserMsg *vmsg, int *do_reply)
 {
     if (vmsg->request == VHOST_USER_NONE) {
         dev->panic(dev, "disconnect");
@@ -XXX,XX +XXX,XX @@ static int vu_block_process_msg(VuDev *dev, VhostUserMsg *vmsg, int *do_reply)
     return false;
 }
 
-static const VuDevIface vu_block_iface = {
-    .get_features          = vu_block_get_features,
-    .queue_set_started     = vu_block_queue_set_started,
-    .get_protocol_features = vu_block_get_protocol_features,
-    .get_config            = vu_block_get_config,
-    .set_config            = vu_block_set_config,
-    .process_msg           = vu_block_process_msg,
+static const VuDevIface vu_blk_iface = {
+    .get_features          = vu_blk_get_features,
+    .queue_set_started     = vu_blk_queue_set_started,
+    .get_protocol_features = vu_blk_get_protocol_features,
+    .get_config            = vu_blk_get_config,
+    .set_config            = vu_blk_set_config,
+    .process_msg           = vu_blk_process_msg,
 };
 
 static void blk_aio_attached(AioContext *ctx, void *opaque)
 {
-    VuBlockDev *vub_dev = opaque;
-    vhost_user_server_attach_aio_context(&vub_dev->vu_server, ctx);
+    VuBlkExport *vexp = opaque;
+    vhost_user_server_attach_aio_context(&vexp->vu_server, ctx);
 }
 
 static void blk_aio_detach(void *opaque)
 {
-    VuBlockDev *vub_dev = opaque;
-    vhost_user_server_detach_aio_context(&vub_dev->vu_server);
+    VuBlkExport *vexp = opaque;
+    vhost_user_server_detach_aio_context(&vexp->vu_server);
 }
 
 static void
-vu_block_initialize_config(BlockDriverState *bs,
+vu_blk_initialize_config(BlockDriverState *bs,
                            struct virtio_blk_config *config, uint32_t blk_size)
 {
     config->capacity = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
@@ -XXX,XX +XXX,XX @@ vu_block_initialize_config(BlockDriverState *bs,
     config->max_write_zeroes_seg = 1;
 }
 
-static VuBlockDev *vu_block_init(VuBlockDev *vu_block_device, Error **errp)
+static void vu_blk_exp_request_shutdown(BlockExport *exp)
 {
+    VuBlkExport *vexp = container_of(exp, VuBlkExport, export);
 
-    BlockBackend *blk;
-    Error *local_error = NULL;
-    const char *node_name = vu_block_device->node_name;
-    bool writable = vu_block_device->writable;
-    uint64_t perm = BLK_PERM_CONSISTENT_READ;
-    int ret;
-
-    AioContext *ctx;
-
-    BlockDriverState *bs = bdrv_lookup_bs(node_name, node_name, &local_error);
-
-    if (!bs) {
-        error_propagate(errp, local_error);
-        return NULL;
-    }
-
-    if (bdrv_is_read_only(bs)) {
-        writable = false;
-    }
-
-    if (writable) {
-        perm |= BLK_PERM_WRITE;
-    }
-
-    ctx = bdrv_get_aio_context(bs);
-    aio_context_acquire(ctx);
-    bdrv_invalidate_cache(bs, NULL);
-    aio_context_release(ctx);
-
-    /*
-     * Don't allow resize while the vhost user server is running,
-     * otherwise we don't care what happens with the node.
-     */
-    blk = blk_new(bdrv_get_aio_context(bs), perm,
-                  BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED |
-                  BLK_PERM_WRITE | BLK_PERM_GRAPH_MOD);
-    ret = blk_insert_bs(blk, bs, errp);
-
-    if (ret < 0) {
-        goto fail;
-    }
-
-    blk_set_enable_write_cache(blk, false);
-
-    blk_set_allow_aio_context_change(blk, true);
-
-    vu_block_device->blkcfg.wce = 0;
-    vu_block_device->backend = blk;
-    if (!vu_block_device->blk_size) {
-        vu_block_device->blk_size = BDRV_SECTOR_SIZE;
-    }
-    vu_block_device->blkcfg.blk_size = vu_block_device->blk_size;
-    blk_set_guest_block_size(blk, vu_block_device->blk_size);
-    vu_block_initialize_config(bs, &vu_block_device->blkcfg,
-                                   vu_block_device->blk_size);
-    return vu_block_device;
-
-fail:
-    blk_unref(blk);
-    return NULL;
-}
-
-static void vu_block_deinit(VuBlockDev *vu_block_device)
-{
-    if (vu_block_device->backend) {
-        blk_remove_aio_context_notifier(vu_block_device->backend, blk_aio_attached,
-                                        blk_aio_detach, vu_block_device);
-    }
-
-    blk_unref(vu_block_device->backend);
-}
-
-static void vhost_user_blk_server_stop(VuBlockDev *vu_block_device)
-{
-    vhost_user_server_stop(&vu_block_device->vu_server);
-    vu_block_deinit(vu_block_device);
-}
-
-static void vhost_user_blk_server_start(VuBlockDev *vu_block_device,
-                                        Error **errp)
-{
-    AioContext *ctx;
-    SocketAddress *addr = vu_block_device->addr;
-
-    if (!vu_block_init(vu_block_device, errp)) {
-        return;
-    }
-
-    ctx = bdrv_get_aio_context(blk_bs(vu_block_device->backend));
-
-    if (!vhost_user_server_start(&vu_block_device->vu_server, addr, ctx,
-                                 VHOST_USER_BLK_MAX_QUEUES, &vu_block_iface,
-                                 errp)) {
-        goto error;
-    }
-
-    blk_add_aio_context_notifier(vu_block_device->backend, blk_aio_attached,
-                                 blk_aio_detach, vu_block_device);
-    vu_block_device->running = true;
-    return;
-
- error:
-    vu_block_deinit(vu_block_device);
-}
-
-static bool vu_prop_modifiable(VuBlockDev *vus, Error **errp)
-{
-    if (vus->running) {
-            error_setg(errp, "The property can't be modified "
-                       "while the server is running");
-            return false;
-    }
-    return true;
-}
-
-static void vu_set_node_name(Object *obj, const char *value, Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-
-    if (!vu_prop_modifiable(vus, errp)) {
-        return;
-    }
-
-    if (vus->node_name) {
-        g_free(vus->node_name);
-    }
-
-    vus->node_name = g_strdup(value);
-}
-
-static char *vu_get_node_name(Object *obj, Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-    return g_strdup(vus->node_name);
-}
-
-static void free_socket_addr(SocketAddress *addr)
-{
-        g_free(addr->u.q_unix.path);
-        g_free(addr);
-}
-
-static void vu_set_unix_socket(Object *obj, const char *value,
-                               Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-
-    if (!vu_prop_modifiable(vus, errp)) {
-        return;
-    }
-
-    if (vus->addr) {
-        free_socket_addr(vus->addr);
-    }
-
-    SocketAddress *addr = g_new0(SocketAddress, 1);
-    addr->type = SOCKET_ADDRESS_TYPE_UNIX;
-    addr->u.q_unix.path = g_strdup(value);
-    vus->addr = addr;
+    vhost_user_server_stop(&vexp->vu_server);
 }
 
-static char *vu_get_unix_socket(Object *obj, Error **errp)
+static int vu_blk_exp_create(BlockExport *exp, BlockExportOptions *opts,
+                             Error **errp)
 {
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-    return g_strdup(vus->addr->u.q_unix.path);
-}
-
-static bool vu_get_block_writable(Object *obj, Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-    return vus->writable;
-}
-
-static void vu_set_block_writable(Object *obj, bool value, Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-
-    if (!vu_prop_modifiable(vus, errp)) {
-            return;
-    }
-
-    vus->writable = value;
-}
-
-static void vu_get_blk_size(Object *obj, Visitor *v, const char *name,
-                            void *opaque, Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-    uint32_t value = vus->blk_size;
-
-    visit_type_uint32(v, name, &value, errp);
-}
-
-static void vu_set_blk_size(Object *obj, Visitor *v, const char *name,
-                            void *opaque, Error **errp)
-{
-    VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
-
+    VuBlkExport *vexp = container_of(exp, VuBlkExport, export);
+    BlockExportOptionsVhostUserBlk *vu_opts = &opts->u.vhost_user_blk;
     Error *local_err = NULL;
-    uint32_t value;
+    uint64_t logical_block_size;
 
-    if (!vu_prop_modifiable(vus, errp)) {
-            return;
-    }
+    vexp->writable = opts->writable;
+    vexp->blkcfg.wce = 0;
 
-    visit_type_uint32(v, name, &value, &local_err);
-    if (local_err) {
-        goto out;
+    if (vu_opts->has_logical_block_size) {
+        logical_block_size = vu_opts->logical_block_size;
+    } else {
+        logical_block_size = BDRV_SECTOR_SIZE;
     }
-
-    check_block_size(object_get_typename(obj), name, value, &local_err);
+    check_block_size(exp->id, "logical-block-size", logical_block_size,
+                     &local_err);
     if (local_err) {
-        goto out;
+        error_propagate(errp, local_err);
+        return -EINVAL;
+    }
+    vexp->blk_size = logical_block_size;
+    blk_set_guest_block_size(exp->blk, logical_block_size);
+    vu_blk_initialize_config(blk_bs(exp->blk), &vexp->blkcfg,
+                               logical_block_size);
+
+    blk_set_allow_aio_context_change(exp->blk, true);
+    blk_add_aio_context_notifier(exp->blk, blk_aio_attached, blk_aio_detach,
+                                 vexp);
+
+    if (!vhost_user_server_start(&vexp->vu_server, vu_opts->addr, exp->ctx,
+                                 VHOST_USER_BLK_MAX_QUEUES, &vu_blk_iface,
+                                 errp)) {
+        blk_remove_aio_context_notifier(exp->blk, blk_aio_attached,
+                                        blk_aio_detach, vexp);
+        return -EADDRNOTAVAIL;
     }
 
-    vus->blk_size = value;
-
-out:
-    error_propagate(errp, local_err);
-}
-
-static void vhost_user_blk_server_instance_finalize(Object *obj)
-{
-    VuBlockDev *vub = VHOST_USER_BLK_SERVER(obj);
-
-    vhost_user_blk_server_stop(vub);
-
-    /*
-     * Unlike object_property_add_str, object_class_property_add_str
-     * doesn't have a release method. Thus manual memory freeing is
-     * needed.
-     */
-    free_socket_addr(vub->addr);
-    g_free(vub->node_name);
-}
-
-static void vhost_user_blk_server_complete(UserCreatable *obj, Error **errp)
-{
-    VuBlockDev *vub = VHOST_USER_BLK_SERVER(obj);
-
-    vhost_user_blk_server_start(vub, errp);
+    return 0;
 }
 
-static void vhost_user_blk_server_class_init(ObjectClass *klass,
-                                             void *class_data)
+static void vu_blk_exp_delete(BlockExport *exp)
 {
-    UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
-    ucc->complete = vhost_user_blk_server_complete;
-
-    object_class_property_add_bool(klass, "writable",
-                                   vu_get_block_writable,
-                                   vu_set_block_writable);
-
-    object_class_property_add_str(klass, "node-name",
-                                  vu_get_node_name,
-                                  vu_set_node_name);
-
-    object_class_property_add_str(klass, "unix-socket",
-                                  vu_get_unix_socket,
-                                  vu_set_unix_socket);
+    VuBlkExport *vexp = container_of(exp, VuBlkExport, export);
 
-    object_class_property_add(klass, "logical-block-size", "uint32",
-                              vu_get_blk_size, vu_set_blk_size,
-                              NULL, NULL);
+    blk_remove_aio_context_notifier(exp->blk, blk_aio_attached, blk_aio_detach,
+                                    vexp);
 }
 
-static const TypeInfo vhost_user_blk_server_info = {
-    .name = TYPE_VHOST_USER_BLK_SERVER,
-    .parent = TYPE_OBJECT,
-    .instance_size = sizeof(VuBlockDev),
-    .instance_finalize = vhost_user_blk_server_instance_finalize,
-    .class_init = vhost_user_blk_server_class_init,
-    .interfaces = (InterfaceInfo[]) {
-        {TYPE_USER_CREATABLE},
-        {}
-    },
+const BlockExportDriver blk_exp_vhost_user_blk = {
+    .type               = BLOCK_EXPORT_TYPE_VHOST_USER_BLK,
+    .instance_size      = sizeof(VuBlkExport),
+    .create             = vu_blk_exp_create,
+    .delete             = vu_blk_exp_delete,
+    .request_shutdown   = vu_blk_exp_request_shutdown,
 };
-
-static void vhost_user_blk_server_register_types(void)
-{
-    type_register_static(&vhost_user_blk_server_info);
-}
-
-type_init(vhost_user_blk_server_register_types)
diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@ bool vhost_user_server_start(VuServer *server,
                              Error **errp)
 {
     QEMUBH *bh;
-    QIONetListener *listener = qio_net_listener_new();
+    QIONetListener *listener;
+
+    if (socket_addr->type != SOCKET_ADDRESS_TYPE_UNIX &&
+        socket_addr->type != SOCKET_ADDRESS_TYPE_FD) {
+        error_setg(errp, "Only socket address types 'unix' and 'fd' are supported");
+        return false;
+    }
+
+    listener = qio_net_listener_new();
     if (qio_net_listener_open_sync(listener, socket_addr, 1,
                                    errp) < 0) {
         object_unref(OBJECT(listener));
diff --git a/block/export/meson.build b/block/export/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/block/export/meson.build
+++ b/block/export/meson.build
@@ -1 +1,2 @@
 block_ss.add(files('export.c'))
+block_ss.add(when: 'CONFIG_LINUX', if_true: files('vhost-user-blk-server.c', '../../contrib/libvhost-user/libvhost-user.c'))
diff --git a/block/meson.build b/block/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/block/meson.build
+++ b/block/meson.build
@@ -XXX,XX +XXX,XX @@ block_ss.add(when: 'CONFIG_WIN32', if_true: files('file-win32.c', 'win32-aio.c')
 block_ss.add(when: 'CONFIG_POSIX', if_true: [files('file-posix.c'), coref, iokit])
 block_ss.add(when: 'CONFIG_LIBISCSI', if_true: files('iscsi-opts.c'))
 block_ss.add(when: 'CONFIG_LINUX', if_true: files('nvme.c'))
-block_ss.add(when: 'CONFIG_LINUX', if_true: files('export/vhost-user-blk-server.c', '../contrib/libvhost-user/libvhost-user.c'))
 block_ss.add(when: 'CONFIG_REPLICATION', if_true: files('replication.c'))
 block_ss.add(when: 'CONFIG_SHEEPDOG', if_true: files('sheepdog.c'))
 block_ss.add(when: ['CONFIG_LINUX_AIO', libaio], if_true: files('linux-aio.c'))
-- 
2.26.2

Headers used by other subsystems are located in include/. Also add the
vhost-user-server and vhost-user-blk-server headers to MAINTAINERS.

diff --git a/MAINTAINERS b/MAINTAINERS
index XXXXXXX..XXXXXXX 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -XXX,XX +XXX,XX @@ Vhost-user block device backend server
 M: Coiby Xu <Coiby.Xu@gmail.com>
 S: Maintained
 F: block/export/vhost-user-blk-server.c
-F: util/vhost-user-server.c
+F: block/export/vhost-user-blk-server.h
+F: include/qemu/vhost-user-server.h
 F: tests/qtest/libqos/vhost-user-blk.c
+F: util/vhost-user-server.c
 
 Replication
 M: Wen Congyang <wencongyang2@huawei.com>
diff --git a/util/vhost-user-server.h b/include/qemu/vhost-user-server.h
similarity index 100%
rename from util/vhost-user-server.h
rename to include/qemu/vhost-user-server.h
diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/vhost-user-blk-server.c
+++ b/block/export/vhost-user-blk-server.c
@@ -XXX,XX +XXX,XX @@
 #include "block/block.h"
 #include "contrib/libvhost-user/libvhost-user.h"
 #include "standard-headers/linux/virtio_blk.h"
-#include "util/vhost-user-server.h"
+#include "qemu/vhost-user-server.h"
 #include "vhost-user-blk-server.h"
 #include "qapi/error.h"
 #include "qom/object_interfaces.h"
diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index XXXXXXX..XXXXXXX 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -XXX,XX +XXX,XX @@
  */
 #include "qemu/osdep.h"
 #include "qemu/main-loop.h"
+#include "qemu/vhost-user-server.h"
 #include "block/aio-wait.h"
-#include "vhost-user-server.h"
 
 /*
  * Theory of operation:
-- 
2.26.2

Don't compile contrib/libvhost-user/libvhost-user.c again. Instead build
the static library once and then reuse it throughout QEMU.

Also switch from CONFIG_LINUX to CONFIG_VHOST_USER, which is what the
vhost-user tools (vhost-user-gpu, etc) do.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200924151549.913737-14-stefanha@redhat.com
[Added CONFIG_LINUX again because libvhost-user doesn't build on macOS.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/export/export.c             | 8 ++++----
 block/export/meson.build          | 2 +-
 contrib/libvhost-user/meson.build | 1 +
 meson.build                       | 6 +++++-
 util/meson.build                  | 4 +++-
 5 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/block/export/export.c b/block/export/export.c
index XXXXXXX..XXXXXXX 100644
--- a/block/export/export.c
+++ b/block/export/export.c
@@ -XXX,XX +XXX,XX @@
 #include "sysemu/block-backend.h"
 #include "block/export.h"
 #include "block/nbd.h"
-#if CONFIG_LINUX
-#include "block/export/vhost-user-blk-server.h"
-#endif
 #include "qapi/error.h"
 #include "qapi/qapi-commands-block-export.h"
 #include "qapi/qapi-events-block-export.h"
 #include "qemu/id.h"
+#ifdef CONFIG_VHOST_USER
+#include "vhost-user-blk-server.h"
+#endif
 
 static const BlockExportDriver *blk_exp_drivers[] = {
     &blk_exp_nbd,
-#if CONFIG_LINUX
+#ifdef CONFIG_VHOST_USER
     &blk_exp_vhost_user_blk,
 #endif
 };
diff --git a/block/export/meson.build b/block/export/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/block/export/meson.build
+++ b/block/export/meson.build
@@ -XXX,XX +XXX,XX @@
 block_ss.add(files('export.c'))
-block_ss.add(when: 'CONFIG_LINUX', if_true: files('vhost-user-blk-server.c', '../../contrib/libvhost-user/libvhost-user.c'))
+block_ss.add(when: ['CONFIG_LINUX', 'CONFIG_VHOST_USER'], if_true: files('vhost-user-blk-server.c'))
diff --git a/contrib/libvhost-user/meson.build b/contrib/libvhost-user/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/contrib/libvhost-user/meson.build
+++ b/contrib/libvhost-user/meson.build
@@ -XXX,XX +XXX,XX @@
 libvhost_user = static_library('vhost-user',
                                files('libvhost-user.c', 'libvhost-user-glib.c'),
                                build_by_default: false)
+vhost_user = declare_dependency(link_with: libvhost_user)
diff --git a/meson.build b/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/meson.build
+++ b/meson.build
@@ -XXX,XX +XXX,XX @@ trace_events_subdirs += [
   'util',
 ]
 
+vhost_user = not_found
+if 'CONFIG_VHOST_USER' in config_host
+  subdir('contrib/libvhost-user')
+endif
+
 subdir('qapi')
 subdir('qobject')
 subdir('stubs')
@@ -XXX,XX +XXX,XX @@ if have_tools
              install: true)
 
   if 'CONFIG_VHOST_USER' in config_host
-    subdir('contrib/libvhost-user')
     subdir('contrib/vhost-user-blk')
     subdir('contrib/vhost-user-gpu')
     subdir('contrib/vhost-user-input')
diff --git a/util/meson.build b/util/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/util/meson.build
+++ b/util/meson.build
@@ -XXX,XX +XXX,XX @@ if have_block
   util_ss.add(files('main-loop.c'))
   util_ss.add(files('nvdimm-utils.c'))
   util_ss.add(files('qemu-coroutine.c', 'qemu-coroutine-lock.c', 'qemu-coroutine-io.c'))
-  util_ss.add(when: 'CONFIG_LINUX', if_true: files('vhost-user-server.c'))
+  util_ss.add(when: ['CONFIG_LINUX', 'CONFIG_VHOST_USER'], if_true: [
+    files('vhost-user-server.c'), vhost_user
+  ])
   util_ss.add(files('block-helpers.c'))
   util_ss.add(files('qemu-coroutine-sleep.c'))
   util_ss.add(files('qemu-co-shared-resource.c'))
-- 
2.26.2

Introduce libblkdev.fa to avoid recompiling blockdev_ss twice.

diff --git a/meson.build b/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/meson.build
+++ b/meson.build
@@ -XXX,XX +XXX,XX @@ blockdev_ss.add(files(
 # os-win32.c does not
 blockdev_ss.add(when: 'CONFIG_POSIX', if_true: files('os-posix.c'))
 softmmu_ss.add(when: 'CONFIG_WIN32', if_true: [files('os-win32.c')])
-softmmu_ss.add_all(blockdev_ss)
 
 common_ss.add(files('cpus-common.c'))
 
@@ -XXX,XX +XXX,XX @@ block = declare_dependency(link_whole: [libblock],
                            link_args: '@block.syms',
                            dependencies: [crypto, io])
 
+blockdev_ss = blockdev_ss.apply(config_host, strict: false)
+libblockdev = static_library('blockdev', blockdev_ss.sources() + genh,
+                             dependencies: blockdev_ss.dependencies(),
+                             name_suffix: 'fa',
+                             build_by_default: false)
+
+blockdev = declare_dependency(link_whole: [libblockdev],
+                              dependencies: [block])
+
 qmp_ss = qmp_ss.apply(config_host, strict: false)
 libqmp = static_library('qmp', qmp_ss.sources() + genh,
                         dependencies: qmp_ss.dependencies(),
@@ -XXX,XX +XXX,XX @@ foreach m : block_mods + softmmu_mods
                 install_dir: config_host['qemu_moddir'])
 endforeach
 
-softmmu_ss.add(authz, block, chardev, crypto, io, qmp)
+softmmu_ss.add(authz, blockdev, chardev, crypto, io, qmp)
 common_ss.add(qom, qemuutil)
 
 common_ss.add_all(when: 'CONFIG_SOFTMMU', if_true: [softmmu_ss])
diff --git a/storage-daemon/meson.build b/storage-daemon/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/storage-daemon/meson.build
+++ b/storage-daemon/meson.build
@@ -XXX,XX +XXX,XX @@
 qsd_ss = ss.source_set()
 qsd_ss.add(files('qemu-storage-daemon.c'))
-qsd_ss.add(block, chardev, qmp, qom, qemuutil)
-qsd_ss.add_all(blockdev_ss)
+qsd_ss.add(blockdev, chardev, qmp, qom, qemuutil)
 
 subdir('qapi')
 
-- 
2.26.2

Block exports are used by softmmu, qemu-storage-daemon, and qemu-nbd.
They are not used by other programs and are not otherwise needed in
libblock.

Undo the recent move of blockdev-nbd.c from blockdev_ss into block_ss.
Since bdrv_close_all() (libblock) calls blk_exp_close_all()
(libblockdev) a stub function is required..

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20200929125516.186715-4-stefanha@redhat.com
[Fixed s/ndb/nbd/ typo in commit description as suggested by Eric Blake
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 qemu-nbd.c                | 21 ++++++++-------------
 stubs/blk-exp-close-all.c |  7 +++++++
 block/export/meson.build  |  4 ++--
 meson.build               |  4 ++--
 nbd/meson.build           |  2 ++
 stubs/meson.build         |  1 +
 6 files changed, 22 insertions(+), 17 deletions(-)
 create mode 100644 stubs/blk-exp-close-all.c

diff --git a/qemu-nbd.c b/qemu-nbd.c
index XXXXXXX..XXXXXXX 100644
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -XXX,XX +XXX,XX @@
 #include "qapi/error.h"
 #include "qemu/cutils.h"
 #include "sysemu/block-backend.h"
+#include "sysemu/runstate.h" /* for qemu_system_killed() prototype */
 #include "block/block_int.h"
 #include "block/nbd.h"
 #include "qemu/main-loop.h"
@@ -XXX,XX +XXX,XX @@ QEMU_COPYRIGHT "\n"
 }
 
 #ifdef CONFIG_POSIX
-static void termsig_handler(int signum)
+/*
+ * The client thread uses SIGTERM to interrupt the server.  A signal
+ * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
+ */
+void qemu_system_killed(int signum, pid_t pid)
 {
     qatomic_cmpxchg(&state, RUNNING, TERMINATE);
     qemu_notify_event();
@@ -XXX,XX +XXX,XX @@ int main(int argc, char **argv)
     BlockExportOptions *export_opts;
 
 #ifdef CONFIG_POSIX
-    /*
-     * Exit gracefully on various signals, which includes SIGTERM used
-     * by 'qemu-nbd -v -c'.
-     */
-    struct sigaction sa_sigterm;
-    memset(&sa_sigterm, 0, sizeof(sa_sigterm));
-    sa_sigterm.sa_handler = termsig_handler;
-    sigaction(SIGTERM, &sa_sigterm, NULL);
-    sigaction(SIGINT, &sa_sigterm, NULL);
-    sigaction(SIGHUP, &sa_sigterm, NULL);
-
-    signal(SIGPIPE, SIG_IGN);
+    os_setup_early_signal_handling();
+    os_setup_signal_handling();
 #endif
 
     socket_init();
diff --git a/stubs/blk-exp-close-all.c b/stubs/blk-exp-close-all.c
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/stubs/blk-exp-close-all.c
@@ -XXX,XX +XXX,XX @@
+#include "qemu/osdep.h"
+#include "block/export.h"
+
+/* Only used in programs that support block exports (libblockdev.fa) */
+void blk_exp_close_all(void)
+{
+}
diff --git a/block/export/meson.build b/block/export/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/block/export/meson.build
+++ b/block/export/meson.build
@@ -XXX,XX +XXX,XX @@
-block_ss.add(files('export.c'))
-block_ss.add(when: ['CONFIG_LINUX', 'CONFIG_VHOST_USER'], if_true: files('vhost-user-blk-server.c'))
+blockdev_ss.add(files('export.c'))
+blockdev_ss.add(when: ['CONFIG_LINUX', 'CONFIG_VHOST_USER'], if_true: files('vhost-user-blk-server.c'))
diff --git a/meson.build b/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/meson.build
+++ b/meson.build
@@ -XXX,XX +XXX,XX @@ subdir('dump')
 
 block_ss.add(files(
   'block.c',
-  'blockdev-nbd.c',
   'blockjob.c',
   'job.c',
   'qemu-io-cmds.c',
@@ -XXX,XX +XXX,XX @@ subdir('block')
 
 blockdev_ss.add(files(
   'blockdev.c',
+  'blockdev-nbd.c',
   'iothread.c',
   'job-qmp.c',
 ))
@@ -XXX,XX +XXX,XX @@ if have_tools
   qemu_io = executable('qemu-io', files('qemu-io.c'),
              dependencies: [block, qemuutil], install: true)
   qemu_nbd = executable('qemu-nbd', files('qemu-nbd.c'),
-               dependencies: [block, qemuutil], install: true)
+               dependencies: [blockdev, qemuutil], install: true)
 
   subdir('storage-daemon')
   subdir('contrib/rdmacm-mux')
diff --git a/nbd/meson.build b/nbd/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/nbd/meson.build
+++ b/nbd/meson.build
@@ -XXX,XX +XXX,XX @@
 block_ss.add(files(
   'client.c',
   'common.c',
+))
+blockdev_ss.add(files(
   'server.c',
 ))
diff --git a/stubs/meson.build b/stubs/meson.build
index XXXXXXX..XXXXXXX 100644
--- a/stubs/meson.build
+++ b/stubs/meson.build
@@ -XXX,XX +XXX,XX @@
 stub_ss.add(files('arch_type.c'))
 stub_ss.add(files('bdrv-next-monitor-owned.c'))
 stub_ss.add(files('blk-commit-all.c'))
+stub_ss.add(files('blk-exp-close-all.c'))
 stub_ss.add(files('blockdev-close-all-bdrv-states.c'))
 stub_ss.add(files('change-state-handler.c'))
 stub_ss.add(files('cmos.c'))
-- 
2.26.2