Series comparison

-[Qemu-devel] [PULL 00/12] Block patches
+[PULL 0/1] Block patches
-The following changes since commit 9964e96dc9999cf7f7c936ee854a795415d19b60:
+The following changes since commit a3607def89f9cd68c1b994e1030527df33aa91d0:
-  Merge remote-tracking branch 'jasowang/tags/net-pull-request' into staging (2017-05-23 15:01:31 +0100)
+  Update version for v6.2.0-rc4 release (2021-12-07 17:51:38 -0800)
-are available in the git repository at:
+are available in the Git repository at:
-  git://github.com/codyprime/qemu-kvm-jtc.git tags/block-pull-request
+  https://gitlab.com/stefanha/qemu.git tags/block-pull-request
-for you to fetch changes up to 223a23c198787328ae75bc65d84edf5fde33c0b6:
+for you to fetch changes up to cf4fbc3030c974fff726756a7ceef8386cdf500b:
-  block/gluster: glfs_lseek() workaround (2017-05-24 16:44:46 -0400)
+  block/nvme: fix infinite loop in nvme_free_req_queue_cb() (2021-12-09 09:19:49 +0000)
 ----------------------------------------------------------------
-Block patches
+Pull request
 An infinite loop fix for the userspace NVMe driver.
 ----------------------------------------------------------------
-Jeff Cody (1):
+Stefan Hajnoczi (1):
-  block/gluster: glfs_lseek() workaround
+  block/nvme: fix infinite loop in nvme_free_req_queue_cb()
-Paolo Bonzini (11):
+ block/nvme.c | 5 +++--
-  blockjob: remove unnecessary check
+file changed, 3 insertions(+), 2 deletions(-)
   blockjob: remove iostatus_reset callback
   blockjob: introduce block_job_early_fail
   blockjob: introduce block_job_pause/resume_all
   blockjob: separate monitor and blockjob APIs
   blockjob: move iostatus reset inside block_job_user_resume
   blockjob: introduce block_job_cancel_async, check iostatus invariants
   blockjob: group BlockJob transaction functions together
   blockjob: strengthen a bit test-blockjob-txn
   blockjob: reorganize block_job_completed_txn_abort
   blockjob: use deferred_to_main_loop to indicate the coroutine has
     ended
  block/backup.c               |   2 +-
  block/commit.c               |   2 +-
  block/gluster.c              |  18 +-
  block/io.c                   |  19 +-
  block/mirror.c               |   2 +-
  blockdev.c                   |   1 -
  blockjob.c                   | 750 ++++++++++++++++++++++++-------------------
  include/block/blockjob.h     |  16 -
  include/block/blockjob_int.h |  27 +-
  tests/test-blockjob-txn.c    |   7 +-
  tests/test-blockjob.c        |  10 +-
 files changed, 463 insertions(+), 391 deletions(-)
 --
-.9.3
+.33.1

-[Qemu-devel] [PULL 01/12] blockjob: remove unnecessary check
+Deleted patch
-From: Paolo Bonzini <pbonzini@redhat.com>
-!job is always checked prior to the call, drop it from here.
-Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
-Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-Reviewed-by: Jeff Cody <jcody@redhat.com>
-Message-id: 20170508141310.8674-2-pbonzini@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- blockjob.c | 2 +-
-file changed, 1 insertion(+), 1 deletion(-)
-diff --git a/blockjob.c b/blockjob.c
-index XXXXXXX..XXXXXXX 100644
---- a/blockjob.c
-+++ b/blockjob.c
-@@ -XXX,XX +XXX,XX @@ static bool block_job_should_pause(BlockJob *job)
- bool block_job_user_paused(BlockJob *job)
- {
--    return job ? job->user_paused : 0;
-+    return job->user_paused;
- }
- void coroutine_fn block_job_pause_point(BlockJob *job)
---
-.9.3

-[Qemu-devel] [PULL 02/12] blockjob: remove iostatus_reset callback
+Deleted patch
-From: Paolo Bonzini <pbonzini@redhat.com>
-This is unused since commit 66a0fae ("blockjob: Don't touch BDS iostatus",
--05-19).
-Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
-Reviewed-by: John Snow <jsnow@redhat.com>
-Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
-Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-Reviewed-by: Jeff Cody <jcody@redhat.com>
-Message-id: 20170508141310.8674-3-pbonzini@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- blockjob.c                   | 3 ---
- include/block/blockjob_int.h | 3 ---
-files changed, 6 deletions(-)
-diff --git a/blockjob.c b/blockjob.c
-index XXXXXXX..XXXXXXX 100644
---- a/blockjob.c
-+++ b/blockjob.c
-@@ -XXX,XX +XXX,XX @@ bool block_job_is_cancelled(BlockJob *job)
- void block_job_iostatus_reset(BlockJob *job)
- {
-     job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
--    if (job->driver->iostatus_reset) {
--        job->driver->iostatus_reset(job);
--    }
- }
- static int block_job_finish_sync(BlockJob *job,
-diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h
-index XXXXXXX..XXXXXXX 100644
---- a/include/block/blockjob_int.h
-+++ b/include/block/blockjob_int.h
-@@ -XXX,XX +XXX,XX @@ struct BlockJobDriver {
-     /** Optional callback for job types that support setting a speed limit */
-     void (*set_speed)(BlockJob *job, int64_t speed, Error **errp);
--    /** Optional callback for job types that need to forward I/O status reset */
--    void (*iostatus_reset)(BlockJob *job);
--
-     /** Mandatory: Entrypoint for the Coroutine. */
-     CoroutineEntry *start;
---
-.9.3

-[Qemu-devel] [PULL 03/12] blockjob: introduce block_job_early_fail
+Deleted patch
-From: Paolo Bonzini <pbonzini@redhat.com>
-Outside blockjob.c, block_job_unref is only used when a block job fails
-to start, and block_job_ref is not used at all.  The reference counting
-thus is pretty well hidden.  Introduce a separate function to be used
-by block jobs; because block_job_ref and block_job_unref now become
-static, move them earlier in blockjob.c.
-Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
-Reviewed-by: John Snow <jsnow@redhat.com>
-Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-Reviewed-by: Jeff Cody <jcody@redhat.com>
-Message-id: 20170508141310.8674-4-pbonzini@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- block/backup.c               |  2 +-
- block/commit.c               |  2 +-
- block/mirror.c               |  2 +-
- blockjob.c                   | 47 ++++++++++++++++++++++++++------------------
- include/block/blockjob_int.h | 15 +++-----------
- tests/test-blockjob.c        | 10 +++++-----
-files changed, 39 insertions(+), 39 deletions(-)
-diff --git a/block/backup.c b/block/backup.c
-index XXXXXXX..XXXXXXX 100644
---- a/block/backup.c
-+++ b/block/backup.c
-@@ -XXX,XX +XXX,XX @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
-     }
-     if (job) {
-         backup_clean(&job->common);
--        block_job_unref(&job->common);
-+        block_job_early_fail(&job->common);
-     }
-     return NULL;
-diff --git a/block/commit.c b/block/commit.c
-index XXXXXXX..XXXXXXX 100644
---- a/block/commit.c
-+++ b/block/commit.c
-@@ -XXX,XX +XXX,XX @@ fail:
-     if (commit_top_bs) {
-         bdrv_set_backing_hd(overlay_bs, top, &error_abort);
-     }
--    block_job_unref(&s->common);
-+    block_job_early_fail(&s->common);
- }
-diff --git a/block/mirror.c b/block/mirror.c
-index XXXXXXX..XXXXXXX 100644
---- a/block/mirror.c
-+++ b/block/mirror.c
-@@ -XXX,XX +XXX,XX @@ fail:
-         g_free(s->replaces);
-         blk_unref(s->target);
--        block_job_unref(&s->common);
-+        block_job_early_fail(&s->common);
-     }
-     bdrv_child_try_set_perm(mirror_top_bs->backing, 0, BLK_PERM_ALL,
-diff --git a/blockjob.c b/blockjob.c
-index XXXXXXX..XXXXXXX 100644
---- a/blockjob.c
-+++ b/blockjob.c
-@@ -XXX,XX +XXX,XX @@ BlockJob *block_job_get(const char *id)
-     return NULL;
- }
-+static void block_job_ref(BlockJob *job)
-+{
-+    ++job->refcnt;
-+}
-+
-+static void block_job_attached_aio_context(AioContext *new_context,
-+                                           void *opaque);
-+static void block_job_detach_aio_context(void *opaque);
-+
-+static void block_job_unref(BlockJob *job)
-+{
-+    if (--job->refcnt == 0) {
-+        BlockDriverState *bs = blk_bs(job->blk);
-+        bs->job = NULL;
-+        block_job_remove_all_bdrv(job);
-+        blk_remove_aio_context_notifier(job->blk,
-+                                        block_job_attached_aio_context,
-+                                        block_job_detach_aio_context, job);
-+        blk_unref(job->blk);
-+        error_free(job->blocker);
-+        g_free(job->id);
-+        QLIST_REMOVE(job, job_list);
-+        g_free(job);
-+    }
-+}
-+
- static void block_job_attached_aio_context(AioContext *new_context,
-                                            void *opaque)
- {
-@@ -XXX,XX +XXX,XX @@ void block_job_start(BlockJob *job)
-     bdrv_coroutine_enter(blk_bs(job->blk), job->co);
- }
--void block_job_ref(BlockJob *job)
-+void block_job_early_fail(BlockJob *job)
- {
--    ++job->refcnt;
--}
--
--void block_job_unref(BlockJob *job)
--{
--    if (--job->refcnt == 0) {
--        BlockDriverState *bs = blk_bs(job->blk);
--        bs->job = NULL;
--        block_job_remove_all_bdrv(job);
--        blk_remove_aio_context_notifier(job->blk,
--                                        block_job_attached_aio_context,
--                                        block_job_detach_aio_context, job);
--        blk_unref(job->blk);
--        error_free(job->blocker);
--        g_free(job->id);
--        QLIST_REMOVE(job, job_list);
--        g_free(job);
--    }
-+    block_job_unref(job);
- }
- static void block_job_completed_single(BlockJob *job)
-diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h
-index XXXXXXX..XXXXXXX 100644
---- a/include/block/blockjob_int.h
-+++ b/include/block/blockjob_int.h
-@@ -XXX,XX +XXX,XX @@ void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns);
- void block_job_yield(BlockJob *job);
- /**
-- * block_job_ref:
-+ * block_job_early_fail:
-  * @bs: The block device.
-  *
-- * Grab a reference to the block job. Should be paired with block_job_unref.
-+ * The block job could not be started, free it.
-  */
--void block_job_ref(BlockJob *job);
--
--/**
-- * block_job_unref:
-- * @bs: The block device.
-- *
-- * Release reference to the block job and release resources if it is the last
-- * reference.
-- */
--void block_job_unref(BlockJob *job);
-+void block_job_early_fail(BlockJob *job);
- /**
-  * block_job_completed:
-diff --git a/tests/test-blockjob.c b/tests/test-blockjob.c
-index XXXXXXX..XXXXXXX 100644
---- a/tests/test-blockjob.c
-+++ b/tests/test-blockjob.c
-@@ -XXX,XX +XXX,XX @@ static void test_job_ids(void)
-     job[1] = do_test_id(blk[1], "id0", false);
-     /* But once job[0] finishes we can reuse its ID */
--    block_job_unref(job[0]);
-+    block_job_early_fail(job[0]);
-     job[1] = do_test_id(blk[1], "id0", true);
-     /* No job ID specified, defaults to the backend name ('drive1') */
--    block_job_unref(job[1]);
-+    block_job_early_fail(job[1]);
-     job[1] = do_test_id(blk[1], NULL, true);
-     /* Duplicate job ID */
-@@ -XXX,XX +XXX,XX @@ static void test_job_ids(void)
-     /* This one is valid */
-     job[2] = do_test_id(blk[2], "id_2", true);
--    block_job_unref(job[0]);
--    block_job_unref(job[1]);
--    block_job_unref(job[2]);
-+    block_job_early_fail(job[0]);
-+    block_job_early_fail(job[1]);
-+    block_job_early_fail(job[2]);
-     destroy_blk(blk[0]);
-     destroy_blk(blk[1]);
---
-.9.3

-[Qemu-devel] [PULL 04/12] blockjob: introduce block_job_pause/resume_all
+Deleted patch
-From: Paolo Bonzini <pbonzini@redhat.com>
-Remove use of block_job_pause/resume from outside blockjob.c, thus
-making them static.  The new functions are used by the block layer,
-so place them in blockjob_int.h.
-Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
-Reviewed-by: John Snow <jsnow@redhat.com>
-Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-Reviewed-by: Jeff Cody <jcody@redhat.com>
-Message-id: 20170508141310.8674-5-pbonzini@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- block/io.c                   |  19 ++------
- blockjob.c                   | 114 ++++++++++++++++++++++++++-----------------
- include/block/blockjob.h     |  16 ------
- include/block/blockjob_int.h |  14 ++++++
-files changed, 86 insertions(+), 77 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 @@
- #include "trace.h"
- #include "sysemu/block-backend.h"
- #include "block/blockjob.h"
-+#include "block/blockjob_int.h"
- #include "block/block_int.h"
- #include "qemu/cutils.h"
- #include "qapi/error.h"
-@@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_begin(void)
-     bool waited = true;
-     BlockDriverState *bs;
-     BdrvNextIterator it;
--    BlockJob *job = NULL;
-     GSList *aio_ctxs = NULL, *ctx;
--    while ((job = block_job_next(job))) {
--        AioContext *aio_context = blk_get_aio_context(job->blk);
--
--        aio_context_acquire(aio_context);
--        block_job_pause(job);
--        aio_context_release(aio_context);
--    }
-+    block_job_pause_all();
-     for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
-         AioContext *aio_context = bdrv_get_aio_context(bs);
-@@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_end(void)
- {
-     BlockDriverState *bs;
-     BdrvNextIterator it;
--    BlockJob *job = NULL;
-     for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
-         AioContext *aio_context = bdrv_get_aio_context(bs);
-@@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_end(void)
-         aio_context_release(aio_context);
-     }
--    while ((job = block_job_next(job))) {
--        AioContext *aio_context = blk_get_aio_context(job->blk);
--
--        aio_context_acquire(aio_context);
--        block_job_resume(job);
--        aio_context_release(aio_context);
--    }
-+    block_job_resume_all();
- }
- void bdrv_drain_all(void)
-diff --git a/blockjob.c b/blockjob.c
-index XXXXXXX..XXXXXXX 100644
---- a/blockjob.c
-+++ b/blockjob.c
-@@ -XXX,XX +XXX,XX @@ struct BlockJobTxn {
- static QLIST_HEAD(, BlockJob) block_jobs = QLIST_HEAD_INITIALIZER(block_jobs);
--static char *child_job_get_parent_desc(BdrvChild *c)
--{
--    BlockJob *job = c->opaque;
--    return g_strdup_printf("%s job '%s'",
--                           BlockJobType_lookup[job->driver->job_type],
--                           job->id);
--}
--
--static const BdrvChildRole child_job = {
--    .get_parent_desc    = child_job_get_parent_desc,
--    .stay_at_node       = true,
--};
--
--static void block_job_drained_begin(void *opaque)
--{
--    BlockJob *job = opaque;
--    block_job_pause(job);
--}
--
--static void block_job_drained_end(void *opaque)
--{
--    BlockJob *job = opaque;
--    block_job_resume(job);
--}
--
--static const BlockDevOps block_job_dev_ops = {
--    .drained_begin = block_job_drained_begin,
--    .drained_end = block_job_drained_end,
--};
--
- BlockJob *block_job_next(BlockJob *job)
- {
-     if (!job) {
-@@ -XXX,XX +XXX,XX @@ BlockJob *block_job_get(const char *id)
-     return NULL;
- }
-+static void block_job_pause(BlockJob *job)
-+{
-+    job->pause_count++;
-+}
-+
-+static void block_job_resume(BlockJob *job)
-+{
-+    assert(job->pause_count > 0);
-+    job->pause_count--;
-+    if (job->pause_count) {
-+        return;
-+    }
-+    block_job_enter(job);
-+}
-+
- static void block_job_ref(BlockJob *job)
- {
-     ++job->refcnt;
-@@ -XXX,XX +XXX,XX @@ static void block_job_detach_aio_context(void *opaque)
-     block_job_unref(job);
- }
-+static char *child_job_get_parent_desc(BdrvChild *c)
-+{
-+    BlockJob *job = c->opaque;
-+    return g_strdup_printf("%s job '%s'",
-+                           BlockJobType_lookup[job->driver->job_type],
-+                           job->id);
-+}
-+
-+static const BdrvChildRole child_job = {
-+    .get_parent_desc    = child_job_get_parent_desc,
-+    .stay_at_node       = true,
-+};
-+
-+static void block_job_drained_begin(void *opaque)
-+{
-+    BlockJob *job = opaque;
-+    block_job_pause(job);
-+}
-+
-+static void block_job_drained_end(void *opaque)
-+{
-+    BlockJob *job = opaque;
-+    block_job_resume(job);
-+}
-+
-+static const BlockDevOps block_job_dev_ops = {
-+    .drained_begin = block_job_drained_begin,
-+    .drained_end = block_job_drained_end,
-+};
-+
- void block_job_remove_all_bdrv(BlockJob *job)
- {
-     GSList *l;
-@@ -XXX,XX +XXX,XX @@ void block_job_complete(BlockJob *job, Error **errp)
-     job->driver->complete(job, errp);
- }
--void block_job_pause(BlockJob *job)
--{
--    job->pause_count++;
--}
--
- void block_job_user_pause(BlockJob *job)
- {
-     job->user_paused = true;
-@@ -XXX,XX +XXX,XX @@ void coroutine_fn block_job_pause_point(BlockJob *job)
-     }
- }
--void block_job_resume(BlockJob *job)
--{
--    assert(job->pause_count > 0);
--    job->pause_count--;
--    if (job->pause_count) {
--        return;
--    }
--    block_job_enter(job);
--}
--
- void block_job_user_resume(BlockJob *job)
- {
-     if (job && job->user_paused && job->pause_count > 0) {
-@@ -XXX,XX +XXX,XX @@ static void block_job_event_completed(BlockJob *job, const char *msg)
-                                         &error_abort);
- }
-+void block_job_pause_all(void)
-+{
-+    BlockJob *job = NULL;
-+    while ((job = block_job_next(job))) {
-+        AioContext *aio_context = blk_get_aio_context(job->blk);
-+
-+        aio_context_acquire(aio_context);
-+        block_job_pause(job);
-+        aio_context_release(aio_context);
-+    }
-+}
-+
-+void block_job_resume_all(void)
-+{
-+    BlockJob *job = NULL;
-+    while ((job = block_job_next(job))) {
-+        AioContext *aio_context = blk_get_aio_context(job->blk);
-+
-+        aio_context_acquire(aio_context);
-+        block_job_resume(job);
-+        aio_context_release(aio_context);
-+    }
-+}
-+
- void block_job_event_ready(BlockJob *job)
- {
-     job->ready = true;
-diff --git a/include/block/blockjob.h b/include/block/blockjob.h
-index XXXXXXX..XXXXXXX 100644
---- a/include/block/blockjob.h
-+++ b/include/block/blockjob.h
-@@ -XXX,XX +XXX,XX @@ void block_job_complete(BlockJob *job, Error **errp);
- BlockJobInfo *block_job_query(BlockJob *job, Error **errp);
- /**
-- * block_job_pause:
-- * @job: The job to be paused.
-- *
-- * Asynchronously pause the specified job.
-- */
--void block_job_pause(BlockJob *job);
--
--/**
-  * block_job_user_pause:
-  * @job: The job to be paused.
-  *
-@@ -XXX,XX +XXX,XX @@ void block_job_user_pause(BlockJob *job);
- bool block_job_user_paused(BlockJob *job);
- /**
-- * block_job_resume:
-- * @job: The job to be resumed.
-- *
-- * Resume the specified job.  Must be paired with a preceding block_job_pause.
-- */
--void block_job_resume(BlockJob *job);
--
--/**
-  * block_job_user_resume:
-  * @job: The job to be resumed.
-  *
-diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h
-index XXXXXXX..XXXXXXX 100644
---- a/include/block/blockjob_int.h
-+++ b/include/block/blockjob_int.h
-@@ -XXX,XX +XXX,XX @@ void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns);
- void block_job_yield(BlockJob *job);
- /**
-+ * block_job_pause_all:
-+ *
-+ * Asynchronously pause all jobs.
-+ */
-+void block_job_pause_all(void);
-+
-+/**
-+ * block_job_resume_all:
-+ *
-+ * Resume all block jobs.  Must be paired with a preceding block_job_pause_all.
-+ */
-+void block_job_resume_all(void);
-+
-+/**
-  * block_job_early_fail:
-  * @bs: The block device.
-  *
---
-.9.3

-[Qemu-devel] [PULL 05/12] blockjob: separate monitor and blockjob APIs
+Deleted patch
-From: Paolo Bonzini <pbonzini@redhat.com>
-We have two different headers for block job operations, blockjob.h
-and blockjob_int.h.  The former contains APIs called by the monitor,
-the latter contains APIs called by the block job drivers and the
-block layer itself.
-Keep the two APIs separate in the blockjob.c file too.  This will
-be useful when transitioning away from the AioContext lock, because
-there will be locking policies for the two categories, too---the
-monitor will have to call new block_job_lock/unlock APIs, while blockjob
-APIs will take care of this for the users.
-Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
-Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-Message-id: 20170508141310.8674-6-pbonzini@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- blockjob.c | 390 ++++++++++++++++++++++++++++++++-----------------------------
-file changed, 205 insertions(+), 185 deletions(-)
-diff --git a/blockjob.c b/blockjob.c
-index XXXXXXX..XXXXXXX 100644
---- a/blockjob.c
-+++ b/blockjob.c
-@@ -XXX,XX +XXX,XX @@ struct BlockJobTxn {
- static QLIST_HEAD(, BlockJob) block_jobs = QLIST_HEAD_INITIALIZER(block_jobs);
-+/*
-+ * The block job API is composed of two categories of functions.
-+ *
-+ * The first includes functions used by the monitor.  The monitor is
-+ * peculiar in that it accesses the block job list with block_job_get, and
-+ * therefore needs consistency across block_job_get and the actual operation
-+ * (e.g. block_job_set_speed).  The consistency is achieved with
-+ * aio_context_acquire/release.  These functions are declared in blockjob.h.
-+ *
-+ * The second includes functions used by the block job drivers and sometimes
-+ * by the core block layer.  These do not care about locking, because the
-+ * whole coroutine runs under the AioContext lock, and are declared in
-+ * blockjob_int.h.
-+ */
-+
- BlockJob *block_job_next(BlockJob *job)
- {
-     if (!job) {
-@@ -XXX,XX +XXX,XX @@ int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs,
-     return 0;
- }
--void *block_job_create(const char *job_id, const BlockJobDriver *driver,
--                       BlockDriverState *bs, uint64_t perm,
--                       uint64_t shared_perm, int64_t speed, int flags,
--                       BlockCompletionFunc *cb, void *opaque, Error **errp)
--{
--    BlockBackend *blk;
--    BlockJob *job;
--    int ret;
--
--    if (bs->job) {
--        error_setg(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
--        return NULL;
--    }
--
--    if (job_id == NULL && !(flags & BLOCK_JOB_INTERNAL)) {
--        job_id = bdrv_get_device_name(bs);
--        if (!*job_id) {
--            error_setg(errp, "An explicit job ID is required for this node");
--            return NULL;
--        }
--    }
--
--    if (job_id) {
--        if (flags & BLOCK_JOB_INTERNAL) {
--            error_setg(errp, "Cannot specify job ID for internal block job");
--            return NULL;
--        }
--
--        if (!id_wellformed(job_id)) {
--            error_setg(errp, "Invalid job ID '%s'", job_id);
--            return NULL;
--        }
--
--        if (block_job_get(job_id)) {
--            error_setg(errp, "Job ID '%s' already in use", job_id);
--            return NULL;
--        }
--    }
--
--    blk = blk_new(perm, shared_perm);
--    ret = blk_insert_bs(blk, bs, errp);
--    if (ret < 0) {
--        blk_unref(blk);
--        return NULL;
--    }
--
--    job = g_malloc0(driver->instance_size);
--    job->driver        = driver;
--    job->id            = g_strdup(job_id);
--    job->blk           = blk;
--    job->cb            = cb;
--    job->opaque        = opaque;
--    job->busy          = false;
--    job->paused        = true;
--    job->pause_count   = 1;
--    job->refcnt        = 1;
--
--    error_setg(&job->blocker, "block device is in use by block job: %s",
--               BlockJobType_lookup[driver->job_type]);
--    block_job_add_bdrv(job, "main node", bs, 0, BLK_PERM_ALL, &error_abort);
--    bs->job = job;
--
--    blk_set_dev_ops(blk, &block_job_dev_ops, job);
--    bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker);
--
--    QLIST_INSERT_HEAD(&block_jobs, job, job_list);
--
--    blk_add_aio_context_notifier(blk, block_job_attached_aio_context,
--                                 block_job_detach_aio_context, job);
--
--    /* Only set speed when necessary to avoid NotSupported error */
--    if (speed != 0) {
--        Error *local_err = NULL;
--
--        block_job_set_speed(job, speed, &local_err);
--        if (local_err) {
--            block_job_unref(job);
--            error_propagate(errp, local_err);
--            return NULL;
--        }
--    }
--    return job;
--}
--
- bool block_job_is_internal(BlockJob *job)
- {
-     return (job->id == NULL);
-@@ -XXX,XX +XXX,XX @@ void block_job_start(BlockJob *job)
-     bdrv_coroutine_enter(blk_bs(job->blk), job->co);
- }
--void block_job_early_fail(BlockJob *job)
--{
--    block_job_unref(job);
--}
--
- static void block_job_completed_single(BlockJob *job)
- {
-     if (!job->ret) {
-@@ -XXX,XX +XXX,XX @@ static void block_job_completed_txn_success(BlockJob *job)
-     }
- }
--void block_job_completed(BlockJob *job, int ret)
--{
--    assert(blk_bs(job->blk)->job == job);
--    assert(!job->completed);
--    job->completed = true;
--    job->ret = ret;
--    if (!job->txn) {
--        block_job_completed_single(job);
--    } else if (ret < 0 || block_job_is_cancelled(job)) {
--        block_job_completed_txn_abort(job);
--    } else {
--        block_job_completed_txn_success(job);
--    }
--}
--
- void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
- {
-     Error *local_err = NULL;
-@@ -XXX,XX +XXX,XX @@ void block_job_user_pause(BlockJob *job)
-     block_job_pause(job);
- }
--static bool block_job_should_pause(BlockJob *job)
--{
--    return job->pause_count > 0;
--}
--
- bool block_job_user_paused(BlockJob *job)
- {
-     return job->user_paused;
- }
--void coroutine_fn block_job_pause_point(BlockJob *job)
--{
--    assert(job && block_job_started(job));
--
--    if (!block_job_should_pause(job)) {
--        return;
--    }
--    if (block_job_is_cancelled(job)) {
--        return;
--    }
--
--    if (job->driver->pause) {
--        job->driver->pause(job);
--    }
--
--    if (block_job_should_pause(job) && !block_job_is_cancelled(job)) {
--        job->paused = true;
--        job->busy = false;
--        qemu_coroutine_yield(); /* wait for block_job_resume() */
--        job->busy = true;
--        job->paused = false;
--    }
--
--    if (job->driver->resume) {
--        job->driver->resume(job);
--    }
--}
--
- void block_job_user_resume(BlockJob *job)
- {
-     if (job && job->user_paused && job->pause_count > 0) {
-@@ -XXX,XX +XXX,XX @@ void block_job_user_resume(BlockJob *job)
-     }
- }
--void block_job_enter(BlockJob *job)
--{
--    if (job->co && !job->busy) {
--        bdrv_coroutine_enter(blk_bs(job->blk), job->co);
--    }
--}
--
- void block_job_cancel(BlockJob *job)
- {
-     if (block_job_started(job)) {
-@@ -XXX,XX +XXX,XX @@ void block_job_cancel(BlockJob *job)
-     }
- }
--bool block_job_is_cancelled(BlockJob *job)
--{
--    return job->cancelled;
--}
--
- void block_job_iostatus_reset(BlockJob *job)
- {
-     job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
-@@ -XXX,XX +XXX,XX @@ int block_job_complete_sync(BlockJob *job, Error **errp)
-     return block_job_finish_sync(job, &block_job_complete, errp);
- }
--void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns)
--{
--    assert(job->busy);
--
--    /* Check cancellation *before* setting busy = false, too!  */
--    if (block_job_is_cancelled(job)) {
--        return;
--    }
--
--    job->busy = false;
--    if (!block_job_should_pause(job)) {
--        co_aio_sleep_ns(blk_get_aio_context(job->blk), type, ns);
--    }
--    job->busy = true;
--
--    block_job_pause_point(job);
--}
--
--void block_job_yield(BlockJob *job)
--{
--    assert(job->busy);
--
--    /* Check cancellation *before* setting busy = false, too!  */
--    if (block_job_is_cancelled(job)) {
--        return;
--    }
--
--    job->busy = false;
--    if (!block_job_should_pause(job)) {
--        qemu_coroutine_yield();
--    }
--    job->busy = true;
--
--    block_job_pause_point(job);
--}
--
- BlockJobInfo *block_job_query(BlockJob *job, Error **errp)
- {
-     BlockJobInfo *info;
-@@ -XXX,XX +XXX,XX @@ static void block_job_event_completed(BlockJob *job, const char *msg)
-                                         &error_abort);
- }
-+/*
-+ * API for block job drivers and the block layer.  These functions are
-+ * declared in blockjob_int.h.
-+ */
-+
-+void *block_job_create(const char *job_id, const BlockJobDriver *driver,
-+                       BlockDriverState *bs, uint64_t perm,
-+                       uint64_t shared_perm, int64_t speed, int flags,
-+                       BlockCompletionFunc *cb, void *opaque, Error **errp)
-+{
-+    BlockBackend *blk;
-+    BlockJob *job;
-+    int ret;
-+
-+    if (bs->job) {
-+        error_setg(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
-+        return NULL;
-+    }
-+
-+    if (job_id == NULL && !(flags & BLOCK_JOB_INTERNAL)) {
-+        job_id = bdrv_get_device_name(bs);
-+        if (!*job_id) {
-+            error_setg(errp, "An explicit job ID is required for this node");
-+            return NULL;
-+        }
-+    }
-+
-+    if (job_id) {
-+        if (flags & BLOCK_JOB_INTERNAL) {
-+            error_setg(errp, "Cannot specify job ID for internal block job");
-+            return NULL;
-+        }
-+
-+        if (!id_wellformed(job_id)) {
-+            error_setg(errp, "Invalid job ID '%s'", job_id);
-+            return NULL;
-+        }
-+
-+        if (block_job_get(job_id)) {
-+            error_setg(errp, "Job ID '%s' already in use", job_id);
-+            return NULL;
-+        }
-+    }
-+
-+    blk = blk_new(perm, shared_perm);
-+    ret = blk_insert_bs(blk, bs, errp);
-+    if (ret < 0) {
-+        blk_unref(blk);
-+        return NULL;
-+    }
-+
-+    job = g_malloc0(driver->instance_size);
-+    job->driver        = driver;
-+    job->id            = g_strdup(job_id);
-+    job->blk           = blk;
-+    job->cb            = cb;
-+    job->opaque        = opaque;
-+    job->busy          = false;
-+    job->paused        = true;
-+    job->pause_count   = 1;
-+    job->refcnt        = 1;
-+
-+    error_setg(&job->blocker, "block device is in use by block job: %s",
-+               BlockJobType_lookup[driver->job_type]);
-+    block_job_add_bdrv(job, "main node", bs, 0, BLK_PERM_ALL, &error_abort);
-+    bs->job = job;
-+
-+    blk_set_dev_ops(blk, &block_job_dev_ops, job);
-+    bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker);
-+
-+    QLIST_INSERT_HEAD(&block_jobs, job, job_list);
-+
-+    blk_add_aio_context_notifier(blk, block_job_attached_aio_context,
-+                                 block_job_detach_aio_context, job);
-+
-+    /* Only set speed when necessary to avoid NotSupported error */
-+    if (speed != 0) {
-+        Error *local_err = NULL;
-+
-+        block_job_set_speed(job, speed, &local_err);
-+        if (local_err) {
-+            block_job_unref(job);
-+            error_propagate(errp, local_err);
-+            return NULL;
-+        }
-+    }
-+    return job;
-+}
-+
- void block_job_pause_all(void)
- {
-     BlockJob *job = NULL;
-@@ -XXX,XX +XXX,XX @@ void block_job_pause_all(void)
-     }
- }
-+void block_job_early_fail(BlockJob *job)
-+{
-+    block_job_unref(job);
-+}
-+
-+void block_job_completed(BlockJob *job, int ret)
-+{
-+    assert(blk_bs(job->blk)->job == job);
-+    assert(!job->completed);
-+    job->completed = true;
-+    job->ret = ret;
-+    if (!job->txn) {
-+        block_job_completed_single(job);
-+    } else if (ret < 0 || block_job_is_cancelled(job)) {
-+        block_job_completed_txn_abort(job);
-+    } else {
-+        block_job_completed_txn_success(job);
-+    }
-+}
-+
-+static bool block_job_should_pause(BlockJob *job)
-+{
-+    return job->pause_count > 0;
-+}
-+
-+void coroutine_fn block_job_pause_point(BlockJob *job)
-+{
-+    assert(job && block_job_started(job));
-+
-+    if (!block_job_should_pause(job)) {
-+        return;
-+    }
-+    if (block_job_is_cancelled(job)) {
-+        return;
-+    }
-+
-+    if (job->driver->pause) {
-+        job->driver->pause(job);
-+    }
-+
-+    if (block_job_should_pause(job) && !block_job_is_cancelled(job)) {
-+        job->paused = true;
-+        job->busy = false;
-+        qemu_coroutine_yield(); /* wait for block_job_resume() */
-+        job->busy = true;
-+        job->paused = false;
-+    }
-+
-+    if (job->driver->resume) {
-+        job->driver->resume(job);
-+    }
-+}
-+
- void block_job_resume_all(void)
- {
-     BlockJob *job = NULL;
-@@ -XXX,XX +XXX,XX @@ void block_job_resume_all(void)
-     }
- }
-+void block_job_enter(BlockJob *job)
-+{
-+    if (job->co && !job->busy) {
-+        bdrv_coroutine_enter(blk_bs(job->blk), job->co);
-+    }
-+}
-+
-+bool block_job_is_cancelled(BlockJob *job)
-+{
-+    return job->cancelled;
-+}
-+
-+void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns)
-+{
-+    assert(job->busy);
-+
-+    /* Check cancellation *before* setting busy = false, too!  */
-+    if (block_job_is_cancelled(job)) {
-+        return;
-+    }
-+
-+    job->busy = false;
-+    if (!block_job_should_pause(job)) {
-+        co_aio_sleep_ns(blk_get_aio_context(job->blk), type, ns);
-+    }
-+    job->busy = true;
-+
-+    block_job_pause_point(job);
-+}
-+
-+void block_job_yield(BlockJob *job)
-+{
-+    assert(job->busy);
-+
-+    /* Check cancellation *before* setting busy = false, too!  */
-+    if (block_job_is_cancelled(job)) {
-+        return;
-+    }
-+
-+    job->busy = false;
-+    if (!block_job_should_pause(job)) {
-+        qemu_coroutine_yield();
-+    }
-+    job->busy = true;
-+
-+    block_job_pause_point(job);
-+}
-+
- void block_job_event_ready(BlockJob *job)
- {
-     job->ready = true;
---
-.9.3

-[Qemu-devel] [PULL 06/12] blockjob: move iostatus reset inside block_job_user_resume
+Deleted patch
-From: Paolo Bonzini <pbonzini@redhat.com>
-Outside blockjob.c, the block_job_iostatus_reset function is used once
-in the monitor and once in BlockBackend.  When we introduce the block
-job mutex, block_job_iostatus_reset's client is going to be the block
-layer (for which blockjob.c will take the block job mutex) rather than
-the monitor (which will take the block job mutex by itself).
-The monitor's call to block_job_iostatus_reset from the monitor comes
-just before the sole call to block_job_user_resume, so reset the
-iostatus directly from block_job_iostatus_reset.  This will avoid
-the need to introduce separate block_job_iostatus_reset and
-block_job_iostatus_reset_locked APIs.
-After making this change, move the function together with the others
-that were moved in the previous patch.
-Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
-Reviewed-by: John Snow <jsnow@redhat.com>
-Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-Reviewed-by: Jeff Cody <jcody@redhat.com>
-Message-id: 20170508141310.8674-7-pbonzini@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- blockdev.c |  1 -
- blockjob.c | 11 ++++++-----
-files changed, 6 insertions(+), 6 deletions(-)
-diff --git a/blockdev.c b/blockdev.c
-index XXXXXXX..XXXXXXX 100644
---- a/blockdev.c
-+++ b/blockdev.c
-@@ -XXX,XX +XXX,XX @@ void qmp_block_job_resume(const char *device, Error **errp)
-     }
-     trace_qmp_block_job_resume(job);
--    block_job_iostatus_reset(job);
-     block_job_user_resume(job);
-     aio_context_release(aio_context);
- }
-diff --git a/blockjob.c b/blockjob.c
-index XXXXXXX..XXXXXXX 100644
---- a/blockjob.c
-+++ b/blockjob.c
-@@ -XXX,XX +XXX,XX @@ void block_job_user_resume(BlockJob *job)
- {
-     if (job && job->user_paused && job->pause_count > 0) {
-         job->user_paused = false;
-+        block_job_iostatus_reset(job);
-         block_job_resume(job);
-     }
- }
-@@ -XXX,XX +XXX,XX @@ void block_job_cancel(BlockJob *job)
-     }
- }
--void block_job_iostatus_reset(BlockJob *job)
--{
--    job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
--}
--
- static int block_job_finish_sync(BlockJob *job,
-                                  void (*finish)(BlockJob *, Error **errp),
-                                  Error **errp)
-@@ -XXX,XX +XXX,XX @@ void block_job_yield(BlockJob *job)
-     block_job_pause_point(job);
- }
-+void block_job_iostatus_reset(BlockJob *job)
-+{
-+    job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
-+}
-+
- void block_job_event_ready(BlockJob *job)
- {
-     job->ready = true;
---
-.9.3

-[Qemu-devel] [PULL 07/12] blockjob: introduce block_job_cancel_async, check iostatus invariants
+Deleted patch
-From: Paolo Bonzini <pbonzini@redhat.com>
-The new functions helps respecting the invariant that the coroutine
-is entered with false user_resume, zero pause count and no error
-recorded in the iostatus.
-Resetting the iostatus is now common to all of block_job_cancel_async,
-block_job_user_resume and block_job_iostatus_reset, albeit with slight
-differences:
-- block_job_cancel_async resets the iostatus, and resumes the job if
-there was an error, but the coroutine is not restarted immediately.
-For example the caller may continue with a call to block_job_finish_sync.
-- block_job_user_resume resets the iostatus.  It wants to resume the job
-unconditionally, even if there was no error.
-- block_job_iostatus_reset doesn't resume the job at all.  Maybe that's
-a bug but it should be fixed separately.
-block_job_iostatus_reset does the least common denominator, so add some
-checking but otherwise leave it as the entry point for resetting the
-iostatus.
-Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
-Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-Message-id: 20170508141310.8674-8-pbonzini@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- blockjob.c | 24 ++++++++++++++++++++----
-file changed, 20 insertions(+), 4 deletions(-)
-diff --git a/blockjob.c b/blockjob.c
-index XXXXXXX..XXXXXXX 100644
---- a/blockjob.c
-+++ b/blockjob.c
-@@ -XXX,XX +XXX,XX @@ static void block_job_completed_single(BlockJob *job)
-     block_job_unref(job);
- }
-+static void block_job_cancel_async(BlockJob *job)
-+{
-+    if (job->iostatus != BLOCK_DEVICE_IO_STATUS_OK) {
-+        block_job_iostatus_reset(job);
-+    }
-+    if (job->user_paused) {
-+        /* Do not call block_job_enter here, the caller will handle it.  */
-+        job->user_paused = false;
-+        job->pause_count--;
-+    }
-+    job->cancelled = true;
-+}
-+
- static void block_job_completed_txn_abort(BlockJob *job)
- {
-     AioContext *ctx;
-@@ -XXX,XX +XXX,XX @@ static void block_job_completed_txn_abort(BlockJob *job)
-              * them; this job, however, may or may not be cancelled, depending
-              * on the caller, so leave it. */
-             if (other_job != job) {
--                other_job->cancelled = true;
-+                block_job_cancel_async(other_job);
-             }
-             continue;
-         }
-@@ -XXX,XX +XXX,XX @@ bool block_job_user_paused(BlockJob *job)
- void block_job_user_resume(BlockJob *job)
- {
-     if (job && job->user_paused && job->pause_count > 0) {
--        job->user_paused = false;
-         block_job_iostatus_reset(job);
-+        job->user_paused = false;
-         block_job_resume(job);
-     }
- }
-@@ -XXX,XX +XXX,XX @@ void block_job_user_resume(BlockJob *job)
- void block_job_cancel(BlockJob *job)
- {
-     if (block_job_started(job)) {
--        job->cancelled = true;
--        block_job_iostatus_reset(job);
-+        block_job_cancel_async(job);
-         block_job_enter(job);
-     } else {
-         block_job_completed(job, -ECANCELED);
-@@ -XXX,XX +XXX,XX @@ void block_job_yield(BlockJob *job)
- void block_job_iostatus_reset(BlockJob *job)
- {
-+    if (job->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
-+        return;
-+    }
-+    assert(job->user_paused && job->pause_count > 0);
-     job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
- }
---
-.9.3

-[Qemu-devel] [PULL 08/12] blockjob: group BlockJob transaction functions together
+Deleted patch
-From: Paolo Bonzini <pbonzini@redhat.com>
-Yet another pure code movement patch, preparing for the next change.
-Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
-Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-Message-id: 20170508141310.8674-9-pbonzini@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- blockjob.c | 128 ++++++++++++++++++++++++++++++-------------------------------
-file changed, 64 insertions(+), 64 deletions(-)
-diff --git a/blockjob.c b/blockjob.c
-index XXXXXXX..XXXXXXX 100644
---- a/blockjob.c
-+++ b/blockjob.c
-@@ -XXX,XX +XXX,XX @@ BlockJob *block_job_get(const char *id)
-     return NULL;
- }
-+BlockJobTxn *block_job_txn_new(void)
-+{
-+    BlockJobTxn *txn = g_new0(BlockJobTxn, 1);
-+    QLIST_INIT(&txn->jobs);
-+    txn->refcnt = 1;
-+    return txn;
-+}
-+
-+static void block_job_txn_ref(BlockJobTxn *txn)
-+{
-+    txn->refcnt++;
-+}
-+
-+void block_job_txn_unref(BlockJobTxn *txn)
-+{
-+    if (txn && --txn->refcnt == 0) {
-+        g_free(txn);
-+    }
-+}
-+
-+void block_job_txn_add_job(BlockJobTxn *txn, BlockJob *job)
-+{
-+    if (!txn) {
-+        return;
-+    }
-+
-+    assert(!job->txn);
-+    job->txn = txn;
-+
-+    QLIST_INSERT_HEAD(&txn->jobs, job, txn_list);
-+    block_job_txn_ref(txn);
-+}
-+
- static void block_job_pause(BlockJob *job)
- {
-     job->pause_count++;
-@@ -XXX,XX +XXX,XX @@ static void block_job_cancel_async(BlockJob *job)
-     job->cancelled = true;
- }
-+static int block_job_finish_sync(BlockJob *job,
-+                                 void (*finish)(BlockJob *, Error **errp),
-+                                 Error **errp)
-+{
-+    Error *local_err = NULL;
-+    int ret;
-+
-+    assert(blk_bs(job->blk)->job == job);
-+
-+    block_job_ref(job);
-+
-+    finish(job, &local_err);
-+    if (local_err) {
-+        error_propagate(errp, local_err);
-+        block_job_unref(job);
-+        return -EBUSY;
-+    }
-+    /* block_job_drain calls block_job_enter, and it should be enough to
-+     * induce progress until the job completes or moves to the main thread.
-+    */
-+    while (!job->deferred_to_main_loop && !job->completed) {
-+        block_job_drain(job);
-+    }
-+    while (!job->completed) {
-+        aio_poll(qemu_get_aio_context(), true);
-+    }
-+    ret = (job->cancelled && job->ret == 0) ? -ECANCELED : job->ret;
-+    block_job_unref(job);
-+    return ret;
-+}
-+
- static void block_job_completed_txn_abort(BlockJob *job)
- {
-     AioContext *ctx;
-@@ -XXX,XX +XXX,XX @@ void block_job_cancel(BlockJob *job)
-     }
- }
--static int block_job_finish_sync(BlockJob *job,
--                                 void (*finish)(BlockJob *, Error **errp),
--                                 Error **errp)
--{
--    Error *local_err = NULL;
--    int ret;
--
--    assert(blk_bs(job->blk)->job == job);
--
--    block_job_ref(job);
--
--    finish(job, &local_err);
--    if (local_err) {
--        error_propagate(errp, local_err);
--        block_job_unref(job);
--        return -EBUSY;
--    }
--    /* block_job_drain calls block_job_enter, and it should be enough to
--     * induce progress until the job completes or moves to the main thread.
--    */
--    while (!job->deferred_to_main_loop && !job->completed) {
--        block_job_drain(job);
--    }
--    while (!job->completed) {
--        aio_poll(qemu_get_aio_context(), true);
--    }
--    ret = (job->cancelled && job->ret == 0) ? -ECANCELED : job->ret;
--    block_job_unref(job);
--    return ret;
--}
--
- /* A wrapper around block_job_cancel() taking an Error ** parameter so it may be
-  * used with block_job_finish_sync() without the need for (rather nasty)
-  * function pointer casts there. */
-@@ -XXX,XX +XXX,XX @@ void block_job_defer_to_main_loop(BlockJob *job,
-     aio_bh_schedule_oneshot(qemu_get_aio_context(),
-                             block_job_defer_to_main_loop_bh, data);
- }
--
--BlockJobTxn *block_job_txn_new(void)
--{
--    BlockJobTxn *txn = g_new0(BlockJobTxn, 1);
--    QLIST_INIT(&txn->jobs);
--    txn->refcnt = 1;
--    return txn;
--}
--
--static void block_job_txn_ref(BlockJobTxn *txn)
--{
--    txn->refcnt++;
--}
--
--void block_job_txn_unref(BlockJobTxn *txn)
--{
--    if (txn && --txn->refcnt == 0) {
--        g_free(txn);
--    }
--}
--
--void block_job_txn_add_job(BlockJobTxn *txn, BlockJob *job)
--{
--    if (!txn) {
--        return;
--    }
--
--    assert(!job->txn);
--    job->txn = txn;
--
--    QLIST_INSERT_HEAD(&txn->jobs, job, txn_list);
--    block_job_txn_ref(txn);
--}
---
-.9.3

-[Qemu-devel] [PULL 09/12] blockjob: strengthen a bit test-blockjob-txn
+Deleted patch
-From: Paolo Bonzini <pbonzini@redhat.com>
-Unlike test-blockjob-txn, QMP releases the reference to the transaction
-before the jobs finish.  Thus, qemu-iotest 124 showed a failure while
-working on the next patch that the unit tests did not have.  Make
-the test a little nastier.
-Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
-Reviewed-by: John Snow <jsnow@redhat.com>
-Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-Message-id: 20170508141310.8674-10-pbonzini@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- tests/test-blockjob-txn.c | 7 +++++--
-file changed, 5 insertions(+), 2 deletions(-)
-diff --git a/tests/test-blockjob-txn.c b/tests/test-blockjob-txn.c
-index XXXXXXX..XXXXXXX 100644
---- a/tests/test-blockjob-txn.c
-+++ b/tests/test-blockjob-txn.c
-@@ -XXX,XX +XXX,XX @@ static void test_pair_jobs(int expected1, int expected2)
-     block_job_start(job1);
-     block_job_start(job2);
-+    /* Release our reference now to trigger as many nice
-+     * use-after-free bugs as possible.
-+     */
-+    block_job_txn_unref(txn);
-+
-     if (expected1 == -ECANCELED) {
-         block_job_cancel(job1);
-     }
-@@ -XXX,XX +XXX,XX @@ static void test_pair_jobs(int expected1, int expected2)
-     g_assert_cmpint(result1, ==, expected1);
-     g_assert_cmpint(result2, ==, expected2);
--
--    block_job_txn_unref(txn);
- }
- static void test_pair_jobs_success(void)
---
-.9.3

-[Qemu-devel] [PULL 10/12] blockjob: reorganize block_job_completed_txn_abort
+Deleted patch
-From: Paolo Bonzini <pbonzini@redhat.com>
-This splits the part that touches job states from the part that invokes
-callbacks.  It will make the code simpler to understand once job states will
-be protected by a different mutex than the AioContext lock.
-Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
-Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-Message-id: 20170508141310.8674-11-pbonzini@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- blockjob.c | 35 ++++++++++++++++++++++-------------
-file changed, 22 insertions(+), 13 deletions(-)
-diff --git a/blockjob.c b/blockjob.c
-index XXXXXXX..XXXXXXX 100644
---- a/blockjob.c
-+++ b/blockjob.c
-@@ -XXX,XX +XXX,XX @@ void block_job_start(BlockJob *job)
- static void block_job_completed_single(BlockJob *job)
- {
-+    assert(job->completed);
-+
-     if (!job->ret) {
-         if (job->driver->commit) {
-             job->driver->commit(job);
-@@ -XXX,XX +XXX,XX @@ static int block_job_finish_sync(BlockJob *job,
-     block_job_ref(job);
--    finish(job, &local_err);
-+    if (finish) {
-+        finish(job, &local_err);
-+    }
-     if (local_err) {
-         error_propagate(errp, local_err);
-         block_job_unref(job);
-@@ -XXX,XX +XXX,XX @@ static void block_job_completed_txn_abort(BlockJob *job)
- {
-     AioContext *ctx;
-     BlockJobTxn *txn = job->txn;
--    BlockJob *other_job, *next;
-+    BlockJob *other_job;
-     if (txn->aborting) {
-         /*
-@@ -XXX,XX +XXX,XX @@ static void block_job_completed_txn_abort(BlockJob *job)
-         return;
-     }
-     txn->aborting = true;
-+    block_job_txn_ref(txn);
-+
-     /* We are the first failed job. Cancel other jobs. */
-     QLIST_FOREACH(other_job, &txn->jobs, txn_list) {
-         ctx = blk_get_aio_context(other_job->blk);
-         aio_context_acquire(ctx);
-     }
-+
-+    /* Other jobs are effectively cancelled by us, set the status for
-+     * them; this job, however, may or may not be cancelled, depending
-+     * on the caller, so leave it. */
-     QLIST_FOREACH(other_job, &txn->jobs, txn_list) {
--        if (other_job == job || other_job->completed) {
--            /* Other jobs are "effectively" cancelled by us, set the status for
--             * them; this job, however, may or may not be cancelled, depending
--             * on the caller, so leave it. */
--            if (other_job != job) {
--                block_job_cancel_async(other_job);
--            }
--            continue;
-+        if (other_job != job) {
-+            block_job_cancel_async(other_job);
-         }
--        block_job_cancel_sync(other_job);
--        assert(other_job->completed);
-     }
--    QLIST_FOREACH_SAFE(other_job, &txn->jobs, txn_list, next) {
-+    while (!QLIST_EMPTY(&txn->jobs)) {
-+        other_job = QLIST_FIRST(&txn->jobs);
-         ctx = blk_get_aio_context(other_job->blk);
-+        if (!other_job->completed) {
-+            assert(other_job->cancelled);
-+            block_job_finish_sync(other_job, NULL, NULL);
-+        }
-         block_job_completed_single(other_job);
-         aio_context_release(ctx);
-     }
-+
-+    block_job_txn_unref(txn);
- }
- static void block_job_completed_txn_success(BlockJob *job)
---
-.9.3

-[Qemu-devel] [PULL 11/12] blockjob: use deferred_to_main_loop to indicate the coroutine has ended
+Deleted patch
-From: Paolo Bonzini <pbonzini@redhat.com>
-All block jobs are using block_job_defer_to_main_loop as the final
-step just before the coroutine terminates.  At this point,
-block_job_enter should do nothing, but currently it restarts
-the freed coroutine.
-Now, the job->co states should probably be changed to an enum
-(e.g. BEFORE_START, STARTED, YIELDED, COMPLETED) subsuming
-block_job_started, job->deferred_to_main_loop and job->busy.
-For now, this patch eliminates the problematic reenter by
-removing the reset of job->deferred_to_main_loop (which served
-no purpose, as far as I could see) and checking the flag in
-block_job_enter.
-Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
-Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-Message-id: 20170508141310.8674-12-pbonzini@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- blockjob.c                   | 10 ++++++++--
- include/block/blockjob_int.h |  3 ++-
-files changed, 10 insertions(+), 3 deletions(-)
-diff --git a/blockjob.c b/blockjob.c
-index XXXXXXX..XXXXXXX 100644
---- a/blockjob.c
-+++ b/blockjob.c
-@@ -XXX,XX +XXX,XX @@ void block_job_resume_all(void)
- void block_job_enter(BlockJob *job)
- {
--    if (job->co && !job->busy) {
-+    if (!block_job_started(job)) {
-+        return;
-+    }
-+    if (job->deferred_to_main_loop) {
-+        return;
-+    }
-+
-+    if (!job->busy) {
-         bdrv_coroutine_enter(blk_bs(job->blk), job->co);
-     }
- }
-@@ -XXX,XX +XXX,XX @@ static void block_job_defer_to_main_loop_bh(void *opaque)
-         aio_context_acquire(aio_context);
-     }
--    data->job->deferred_to_main_loop = false;
-     data->fn(data->job, data->opaque);
-     if (aio_context != data->aio_context) {
-diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h
-index XXXXXXX..XXXXXXX 100644
---- a/include/block/blockjob_int.h
-+++ b/include/block/blockjob_int.h
-@@ -XXX,XX +XXX,XX @@ typedef void BlockJobDeferToMainLoopFn(BlockJob *job, void *opaque);
-  * @fn: The function to run in the main loop
-  * @opaque: The opaque value that is passed to @fn
-  *
-- * Execute a given function in the main loop with the BlockDriverState
-+ * This function must be called by the main job coroutine just before it
-+ * returns.  @fn is executed in the main loop with the BlockDriverState
-  * AioContext acquired.  Block jobs must call bdrv_unref(), bdrv_close(), and
-  * anything that uses bdrv_drain_all() in the main loop.
-  *
---
-.9.3

-[Qemu-devel] [PULL 12/12] block/gluster: glfs_lseek() workaround
+[PULL 1/1] block/nvme: fix infinite loop in nvme_free_req_queue_cb()
-On current released versions of glusterfs, glfs_lseek() will sometimes
+When the request free list is exhausted the coroutine waits on
-return invalid values for SEEK_DATA or SEEK_HOLE.  For SEEK_DATA and
+q->free_req_queue for the next free request. Whenever a request is
-SEEK_HOLE, the returned value should be >= the passed offset, or < 0 in
+completed a BH is scheduled to invoke nvme_free_req_queue_cb() and wake
-the case of error:
+up waiting coroutines.
-LSEEK(2):
+. nvme_get_free_req() waits for a free request:
-    off_t lseek(int fd, off_t offset, int whence);
+    while (q->free_req_head == -1) {
+        ...
-    [...]
+            trace_nvme_free_req_queue_wait(q->s, q->index);
+            qemu_co_queue_wait(&q->free_req_queue, &q->lock);
-    SEEK_HOLE
+        ...
               Adjust  the file offset to the next hole in the file greater
               than or equal to offset.  If offset points into the middle of
               a hole, then the file offset is set to offset.  If there is no
               hole past offset, then the file offset is adjusted to the end
               of the file (i.e., there is  an implicit hole at the end of
               any file).
     [...]
     RETURN VALUE
               Upon  successful  completion,  lseek()  returns  the resulting
               offset location as measured in bytes from the beginning of the
               file.  On error, the value (off_t) -1 is returned and errno is
               set to indicate the error
 However, occasionally glfs_lseek() for SEEK_HOLE/DATA will return a
 value less than the passed offset, yet greater than zero.
 For instance, here are example values observed from this call:
     offs = glfs_lseek(s->fd, start, SEEK_HOLE);
     if (offs < 0) {
         return -errno;          /* D1 and (H3 or H4) */
     }
-start == 7608336384
+. nvme_free_req_queue_cb() wakes up the coroutine:
 offs == 7607877632
-This causes QEMU to abort on the assert test.  When this value is
+    while (qemu_co_enter_next(&q->free_req_queue, &q->lock)) {
-returned, errno is also 0.
+       ^--- infinite loop when free_req_head == -1
     }
-This is a reported and known bug to glusterfs:
+nvme_free_req_queue_cb() and the coroutine form an infinite loop when
-https://bugzilla.redhat.com/show_bug.cgi?id=1425293
+q->free_req_head == -1. Fix this by checking q->free_req_head in
 nvme_free_req_queue_cb(). If the free request list is exhausted, don't
 wake waiting coroutines. Eventually an in-flight request will complete
 and the BH will be scheduled again, guaranteeing forward progress.
-Although this is being fixed in gluster, we still should work around it
+Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
-in QEMU, given that multiple released versions of gluster behave this
+Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
-way.
+Message-id: 20211208152246.244585-1-stefanha@redhat.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
  block/nvme.c | 5 +++--
 file changed, 3 insertions(+), 2 deletions(-)
-This patch treats the return case of (offs < start) the same as if an
+diff --git a/block/nvme.c b/block/nvme.c
 error value other than ENXIO is returned; we will assume we learned
 nothing, and there are no holes in the file.
 Signed-off-by: Jeff Cody <jcody@redhat.com>
 Reviewed-by: Eric Blake <eblake@redhat.com>
 Reviewed-by: Niels de Vos <ndevos@redhat.com>
 Message-id: 87c0140e9407c08f6e74b04131b610f2e27c014c.1495560397.git.jcody@redhat.com
 Signed-off-by: Jeff Cody <jcody@redhat.com>
 ---
  block/gluster.c | 18 ++++++++++++++++--
 file changed, 16 insertions(+), 2 deletions(-)
 diff --git a/block/gluster.c b/block/gluster.c
 index XXXXXXX..XXXXXXX 100644
---- a/block/gluster.c
+--- a/block/nvme.c
-+++ b/block/gluster.c
++++ b/block/nvme.c
-@@ -XXX,XX +XXX,XX @@ static int find_allocation(BlockDriverState *bs, off_t start,
+@@ -XXX,XX +XXX,XX @@ static void nvme_free_req_queue_cb(void *opaque)
-     if (offs < 0) {
+     NVMeQueuePair *q = opaque;
-         return -errno;          /* D3 or D4 */
      qemu_mutex_lock(&q->lock);
 -    while (qemu_co_enter_next(&q->free_req_queue, &q->lock)) {
 -        /* Retry all pending requests */
 +    while (q->free_req_head != -1 &&
 +           qemu_co_enter_next(&q->free_req_queue, &q->lock)) {
 +        /* Retry waiting requests */
      }
--    assert(offs >= start);
+     qemu_mutex_unlock(&q->lock);
-+
+ }
 +    if (offs < start) {
 +        /* This is not a valid return by lseek().  We are safe to just return
 +         * -EIO in this case, and we'll treat it like D4. Unfortunately some
 +         *  versions of gluster server will return offs < start, so an assert
 +         *  here will unnecessarily abort QEMU. */
 +        return -EIO;
 +    }
      if (offs > start) {
          /* D2: in hole, next data at offs */
@@ -XXX,XX +XXX,XX @@ static int find_allocation(BlockDriverState *bs, off_t start,
      if (offs < 0) {
          return -errno;          /* D1 and (H3 or H4) */
      }
 -    assert(offs >= start);
 +
 +    if (offs < start) {
 +        /* This is not a valid return by lseek().  We are safe to just return
 +         * -EIO in this case, and we'll treat it like H4. Unfortunately some
 +         *  versions of gluster server will return offs < start, so an assert
 +         *  here will unnecessarily abort QEMU. */
 +        return -EIO;
 +    }
      if (offs > start) {
          /*
 --
-.9.3
+.33.1

The following changes since commit 9964e96dc9999cf7f7c936ee854a795415d19b60:

Merge remote-tracking branch 'jasowang/tags/net-pull-request' into staging (2017-05-23 15:01:31 +0100)

are available in the git repository at:

git://github.com/codyprime/qemu-kvm-jtc.git tags/block-pull-request

for you to fetch changes up to 223a23c198787328ae75bc65d84edf5fde33c0b6:

block/gluster: glfs_lseek() workaround (2017-05-24 16:44:46 -0400)

----------------------------------------------------------------
Block patches
----------------------------------------------------------------

Jeff Cody (1):
  block/gluster: glfs_lseek() workaround

Paolo Bonzini (11):
  blockjob: remove unnecessary check
  blockjob: remove iostatus_reset callback
  blockjob: introduce block_job_early_fail
  blockjob: introduce block_job_pause/resume_all
  blockjob: separate monitor and blockjob APIs
  blockjob: move iostatus reset inside block_job_user_resume
  blockjob: introduce block_job_cancel_async, check iostatus invariants
  blockjob: group BlockJob transaction functions together
  blockjob: strengthen a bit test-blockjob-txn
  blockjob: reorganize block_job_completed_txn_abort
  blockjob: use deferred_to_main_loop to indicate the coroutine has
    ended

-- 
2.9.3

From: Paolo Bonzini <pbonzini@redhat.com>

This is unused since commit 66a0fae ("blockjob: Don't touch BDS iostatus",
2016-05-19).

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 20170508141310.8674-3-pbonzini@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 blockjob.c                   | 3 ---
 include/block/blockjob_int.h | 3 ---
 2 files changed, 6 deletions(-)

diff --git a/blockjob.c b/blockjob.c
index XXXXXXX..XXXXXXX 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -XXX,XX +XXX,XX @@ bool block_job_is_cancelled(BlockJob *job)
 void block_job_iostatus_reset(BlockJob *job)
 {
     job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
-    if (job->driver->iostatus_reset) {
-        job->driver->iostatus_reset(job);
-    }
 }
 
 static int block_job_finish_sync(BlockJob *job,
diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h
index XXXXXXX..XXXXXXX 100644
--- a/include/block/blockjob_int.h
+++ b/include/block/blockjob_int.h
@@ -XXX,XX +XXX,XX @@ struct BlockJobDriver {
     /** Optional callback for job types that support setting a speed limit */
     void (*set_speed)(BlockJob *job, int64_t speed, Error **errp);
 
-    /** Optional callback for job types that need to forward I/O status reset */
-    void (*iostatus_reset)(BlockJob *job);
-
     /** Mandatory: Entrypoint for the Coroutine. */
     CoroutineEntry *start;
 
-- 
2.9.3

From: Paolo Bonzini <pbonzini@redhat.com>

Outside blockjob.c, block_job_unref is only used when a block job fails
to start, and block_job_ref is not used at all.  The reference counting
thus is pretty well hidden.  Introduce a separate function to be used
by block jobs; because block_job_ref and block_job_unref now become
static, move them earlier in blockjob.c.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 20170508141310.8674-4-pbonzini@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/backup.c               |  2 +-
 block/commit.c               |  2 +-
 block/mirror.c               |  2 +-
 blockjob.c                   | 47 ++++++++++++++++++++++++++------------------
 include/block/blockjob_int.h | 15 +++-----------
 tests/test-blockjob.c        | 10 +++++-----
 6 files changed, 39 insertions(+), 39 deletions(-)

diff --git a/block/backup.c b/block/backup.c
index XXXXXXX..XXXXXXX 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -XXX,XX +XXX,XX @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     }
     if (job) {
         backup_clean(&job->common);
-        block_job_unref(&job->common);
+        block_job_early_fail(&job->common);
     }
 
     return NULL;
diff --git a/block/commit.c b/block/commit.c
index XXXXXXX..XXXXXXX 100644
--- a/block/commit.c
+++ b/block/commit.c
@@ -XXX,XX +XXX,XX @@ fail:
     if (commit_top_bs) {
         bdrv_set_backing_hd(overlay_bs, top, &error_abort);
     }
-    block_job_unref(&s->common);
+    block_job_early_fail(&s->common);
 }
 
 
diff --git a/block/mirror.c b/block/mirror.c
index XXXXXXX..XXXXXXX 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -XXX,XX +XXX,XX @@ fail:
 
         g_free(s->replaces);
         blk_unref(s->target);
-        block_job_unref(&s->common);
+        block_job_early_fail(&s->common);
     }
 
     bdrv_child_try_set_perm(mirror_top_bs->backing, 0, BLK_PERM_ALL,
diff --git a/blockjob.c b/blockjob.c
index XXXXXXX..XXXXXXX 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -XXX,XX +XXX,XX @@ BlockJob *block_job_get(const char *id)
     return NULL;
 }
 
+static void block_job_ref(BlockJob *job)
+{
+    ++job->refcnt;
+}
+
+static void block_job_attached_aio_context(AioContext *new_context,
+                                           void *opaque);
+static void block_job_detach_aio_context(void *opaque);
+
+static void block_job_unref(BlockJob *job)
+{
+    if (--job->refcnt == 0) {
+        BlockDriverState *bs = blk_bs(job->blk);
+        bs->job = NULL;
+        block_job_remove_all_bdrv(job);
+        blk_remove_aio_context_notifier(job->blk,
+                                        block_job_attached_aio_context,
+                                        block_job_detach_aio_context, job);
+        blk_unref(job->blk);
+        error_free(job->blocker);
+        g_free(job->id);
+        QLIST_REMOVE(job, job_list);
+        g_free(job);
+    }
+}
+
 static void block_job_attached_aio_context(AioContext *new_context,
                                            void *opaque)
 {
@@ -XXX,XX +XXX,XX @@ void block_job_start(BlockJob *job)
     bdrv_coroutine_enter(blk_bs(job->blk), job->co);
 }
 
-void block_job_ref(BlockJob *job)
+void block_job_early_fail(BlockJob *job)
 {
-    ++job->refcnt;
-}
-
-void block_job_unref(BlockJob *job)
-{
-    if (--job->refcnt == 0) {
-        BlockDriverState *bs = blk_bs(job->blk);
-        bs->job = NULL;
-        block_job_remove_all_bdrv(job);
-        blk_remove_aio_context_notifier(job->blk,
-                                        block_job_attached_aio_context,
-                                        block_job_detach_aio_context, job);
-        blk_unref(job->blk);
-        error_free(job->blocker);
-        g_free(job->id);
-        QLIST_REMOVE(job, job_list);
-        g_free(job);
-    }
+    block_job_unref(job);
 }
 
 static void block_job_completed_single(BlockJob *job)
diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h
index XXXXXXX..XXXXXXX 100644
--- a/include/block/blockjob_int.h
+++ b/include/block/blockjob_int.h
@@ -XXX,XX +XXX,XX @@ void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns);
 void block_job_yield(BlockJob *job);
 
 /**
- * block_job_ref:
+ * block_job_early_fail:
  * @bs: The block device.
  *
- * Grab a reference to the block job. Should be paired with block_job_unref.
+ * The block job could not be started, free it.
  */
-void block_job_ref(BlockJob *job);
-
-/**
- * block_job_unref:
- * @bs: The block device.
- *
- * Release reference to the block job and release resources if it is the last
- * reference.
- */
-void block_job_unref(BlockJob *job);
+void block_job_early_fail(BlockJob *job);
 
 /**
  * block_job_completed:
diff --git a/tests/test-blockjob.c b/tests/test-blockjob.c
index XXXXXXX..XXXXXXX 100644
--- a/tests/test-blockjob.c
+++ b/tests/test-blockjob.c
@@ -XXX,XX +XXX,XX @@ static void test_job_ids(void)
     job[1] = do_test_id(blk[1], "id0", false);
 
     /* But once job[0] finishes we can reuse its ID */
-    block_job_unref(job[0]);
+    block_job_early_fail(job[0]);
     job[1] = do_test_id(blk[1], "id0", true);
 
     /* No job ID specified, defaults to the backend name ('drive1') */
-    block_job_unref(job[1]);
+    block_job_early_fail(job[1]);
     job[1] = do_test_id(blk[1], NULL, true);
 
     /* Duplicate job ID */
@@ -XXX,XX +XXX,XX @@ static void test_job_ids(void)
     /* This one is valid */
     job[2] = do_test_id(blk[2], "id_2", true);
 
-    block_job_unref(job[0]);
-    block_job_unref(job[1]);
-    block_job_unref(job[2]);
+    block_job_early_fail(job[0]);
+    block_job_early_fail(job[1]);
+    block_job_early_fail(job[2]);
 
     destroy_blk(blk[0]);
     destroy_blk(blk[1]);
-- 
2.9.3

From: Paolo Bonzini <pbonzini@redhat.com>

Remove use of block_job_pause/resume from outside blockjob.c, thus
making them static.  The new functions are used by the block layer,
so place them in blockjob_int.h.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 20170508141310.8674-5-pbonzini@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/io.c                   |  19 ++------
 blockjob.c                   | 114 ++++++++++++++++++++++++++-----------------
 include/block/blockjob.h     |  16 ------
 include/block/blockjob_int.h |  14 ++++++
 4 files changed, 86 insertions(+), 77 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 @@
 #include "trace.h"
 #include "sysemu/block-backend.h"
 #include "block/blockjob.h"
+#include "block/blockjob_int.h"
 #include "block/block_int.h"
 #include "qemu/cutils.h"
 #include "qapi/error.h"
@@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_begin(void)
     bool waited = true;
     BlockDriverState *bs;
     BdrvNextIterator it;
-    BlockJob *job = NULL;
     GSList *aio_ctxs = NULL, *ctx;
 
-    while ((job = block_job_next(job))) {
-        AioContext *aio_context = blk_get_aio_context(job->blk);
-
-        aio_context_acquire(aio_context);
-        block_job_pause(job);
-        aio_context_release(aio_context);
-    }
+    block_job_pause_all();
 
     for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
         AioContext *aio_context = bdrv_get_aio_context(bs);
@@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_end(void)
 {
     BlockDriverState *bs;
     BdrvNextIterator it;
-    BlockJob *job = NULL;
 
     for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
         AioContext *aio_context = bdrv_get_aio_context(bs);
@@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_end(void)
         aio_context_release(aio_context);
     }
 
-    while ((job = block_job_next(job))) {
-        AioContext *aio_context = blk_get_aio_context(job->blk);
-
-        aio_context_acquire(aio_context);
-        block_job_resume(job);
-        aio_context_release(aio_context);
-    }
+    block_job_resume_all();
 }
 
 void bdrv_drain_all(void)
diff --git a/blockjob.c b/blockjob.c
index XXXXXXX..XXXXXXX 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -XXX,XX +XXX,XX @@ struct BlockJobTxn {
 
 static QLIST_HEAD(, BlockJob) block_jobs = QLIST_HEAD_INITIALIZER(block_jobs);
 
-static char *child_job_get_parent_desc(BdrvChild *c)
-{
-    BlockJob *job = c->opaque;
-    return g_strdup_printf("%s job '%s'",
-                           BlockJobType_lookup[job->driver->job_type],
-                           job->id);
-}
-
-static const BdrvChildRole child_job = {
-    .get_parent_desc    = child_job_get_parent_desc,
-    .stay_at_node       = true,
-};
-
-static void block_job_drained_begin(void *opaque)
-{
-    BlockJob *job = opaque;
-    block_job_pause(job);
-}
-
-static void block_job_drained_end(void *opaque)
-{
-    BlockJob *job = opaque;
-    block_job_resume(job);
-}
-
-static const BlockDevOps block_job_dev_ops = {
-    .drained_begin = block_job_drained_begin,
-    .drained_end = block_job_drained_end,
-};
-
 BlockJob *block_job_next(BlockJob *job)
 {
     if (!job) {
@@ -XXX,XX +XXX,XX @@ BlockJob *block_job_get(const char *id)
     return NULL;
 }
 
+static void block_job_pause(BlockJob *job)
+{
+    job->pause_count++;
+}
+
+static void block_job_resume(BlockJob *job)
+{
+    assert(job->pause_count > 0);
+    job->pause_count--;
+    if (job->pause_count) {
+        return;
+    }
+    block_job_enter(job);
+}
+
 static void block_job_ref(BlockJob *job)
 {
     ++job->refcnt;
@@ -XXX,XX +XXX,XX @@ static void block_job_detach_aio_context(void *opaque)
     block_job_unref(job);
 }
 
+static char *child_job_get_parent_desc(BdrvChild *c)
+{
+    BlockJob *job = c->opaque;
+    return g_strdup_printf("%s job '%s'",
+                           BlockJobType_lookup[job->driver->job_type],
+                           job->id);
+}
+
+static const BdrvChildRole child_job = {
+    .get_parent_desc    = child_job_get_parent_desc,
+    .stay_at_node       = true,
+};
+
+static void block_job_drained_begin(void *opaque)
+{
+    BlockJob *job = opaque;
+    block_job_pause(job);
+}
+
+static void block_job_drained_end(void *opaque)
+{
+    BlockJob *job = opaque;
+    block_job_resume(job);
+}
+
+static const BlockDevOps block_job_dev_ops = {
+    .drained_begin = block_job_drained_begin,
+    .drained_end = block_job_drained_end,
+};
+
 void block_job_remove_all_bdrv(BlockJob *job)
 {
     GSList *l;
@@ -XXX,XX +XXX,XX @@ void block_job_complete(BlockJob *job, Error **errp)
     job->driver->complete(job, errp);
 }
 
-void block_job_pause(BlockJob *job)
-{
-    job->pause_count++;
-}
-
 void block_job_user_pause(BlockJob *job)
 {
     job->user_paused = true;
@@ -XXX,XX +XXX,XX @@ void coroutine_fn block_job_pause_point(BlockJob *job)
     }
 }
 
-void block_job_resume(BlockJob *job)
-{
-    assert(job->pause_count > 0);
-    job->pause_count--;
-    if (job->pause_count) {
-        return;
-    }
-    block_job_enter(job);
-}
-
 void block_job_user_resume(BlockJob *job)
 {
     if (job && job->user_paused && job->pause_count > 0) {
@@ -XXX,XX +XXX,XX @@ static void block_job_event_completed(BlockJob *job, const char *msg)
                                         &error_abort);
 }
 
+void block_job_pause_all(void)
+{
+    BlockJob *job = NULL;
+    while ((job = block_job_next(job))) {
+        AioContext *aio_context = blk_get_aio_context(job->blk);
+
+        aio_context_acquire(aio_context);
+        block_job_pause(job);
+        aio_context_release(aio_context);
+    }
+}
+
+void block_job_resume_all(void)
+{
+    BlockJob *job = NULL;
+    while ((job = block_job_next(job))) {
+        AioContext *aio_context = blk_get_aio_context(job->blk);
+
+        aio_context_acquire(aio_context);
+        block_job_resume(job);
+        aio_context_release(aio_context);
+    }
+}
+
 void block_job_event_ready(BlockJob *job)
 {
     job->ready = true;
diff --git a/include/block/blockjob.h b/include/block/blockjob.h
index XXXXXXX..XXXXXXX 100644
--- a/include/block/blockjob.h
+++ b/include/block/blockjob.h
@@ -XXX,XX +XXX,XX @@ void block_job_complete(BlockJob *job, Error **errp);
 BlockJobInfo *block_job_query(BlockJob *job, Error **errp);
 
 /**
- * block_job_pause:
- * @job: The job to be paused.
- *
- * Asynchronously pause the specified job.
- */
-void block_job_pause(BlockJob *job);
-
-/**
  * block_job_user_pause:
  * @job: The job to be paused.
  *
@@ -XXX,XX +XXX,XX @@ void block_job_user_pause(BlockJob *job);
 bool block_job_user_paused(BlockJob *job);
 
 /**
- * block_job_resume:
- * @job: The job to be resumed.
- *
- * Resume the specified job.  Must be paired with a preceding block_job_pause.
- */
-void block_job_resume(BlockJob *job);
-
-/**
  * block_job_user_resume:
  * @job: The job to be resumed.
  *
diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h
index XXXXXXX..XXXXXXX 100644
--- a/include/block/blockjob_int.h
+++ b/include/block/blockjob_int.h
@@ -XXX,XX +XXX,XX @@ void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns);
 void block_job_yield(BlockJob *job);
 
 /**
+ * block_job_pause_all:
+ *
+ * Asynchronously pause all jobs.
+ */
+void block_job_pause_all(void);
+
+/**
+ * block_job_resume_all:
+ *
+ * Resume all block jobs.  Must be paired with a preceding block_job_pause_all.
+ */
+void block_job_resume_all(void);
+
+/**
  * block_job_early_fail:
  * @bs: The block device.
  *
-- 
2.9.3

From: Paolo Bonzini <pbonzini@redhat.com>

We have two different headers for block job operations, blockjob.h
and blockjob_int.h.  The former contains APIs called by the monitor,
the latter contains APIs called by the block job drivers and the
block layer itself.

Keep the two APIs separate in the blockjob.c file too.  This will
be useful when transitioning away from the AioContext lock, because
there will be locking policies for the two categories, too---the
monitor will have to call new block_job_lock/unlock APIs, while blockjob
APIs will take care of this for the users.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20170508141310.8674-6-pbonzini@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 blockjob.c | 390 ++++++++++++++++++++++++++++++++-----------------------------
 1 file changed, 205 insertions(+), 185 deletions(-)

diff --git a/blockjob.c b/blockjob.c
index XXXXXXX..XXXXXXX 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -XXX,XX +XXX,XX @@ struct BlockJobTxn {
 
 static QLIST_HEAD(, BlockJob) block_jobs = QLIST_HEAD_INITIALIZER(block_jobs);
 
+/*
+ * The block job API is composed of two categories of functions.
+ *
+ * The first includes functions used by the monitor.  The monitor is
+ * peculiar in that it accesses the block job list with block_job_get, and
+ * therefore needs consistency across block_job_get and the actual operation
+ * (e.g. block_job_set_speed).  The consistency is achieved with
+ * aio_context_acquire/release.  These functions are declared in blockjob.h.
+ *
+ * The second includes functions used by the block job drivers and sometimes
+ * by the core block layer.  These do not care about locking, because the
+ * whole coroutine runs under the AioContext lock, and are declared in
+ * blockjob_int.h.
+ */
+
 BlockJob *block_job_next(BlockJob *job)
 {
     if (!job) {
@@ -XXX,XX +XXX,XX @@ int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs,
     return 0;
 }
 
-void *block_job_create(const char *job_id, const BlockJobDriver *driver,
-                       BlockDriverState *bs, uint64_t perm,
-                       uint64_t shared_perm, int64_t speed, int flags,
-                       BlockCompletionFunc *cb, void *opaque, Error **errp)
-{
-    BlockBackend *blk;
-    BlockJob *job;
-    int ret;
-
-    if (bs->job) {
-        error_setg(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
-        return NULL;
-    }
-
-    if (job_id == NULL && !(flags & BLOCK_JOB_INTERNAL)) {
-        job_id = bdrv_get_device_name(bs);
-        if (!*job_id) {
-            error_setg(errp, "An explicit job ID is required for this node");
-            return NULL;
-        }
-    }
-
-    if (job_id) {
-        if (flags & BLOCK_JOB_INTERNAL) {
-            error_setg(errp, "Cannot specify job ID for internal block job");
-            return NULL;
-        }
-
-        if (!id_wellformed(job_id)) {
-            error_setg(errp, "Invalid job ID '%s'", job_id);
-            return NULL;
-        }
-
-        if (block_job_get(job_id)) {
-            error_setg(errp, "Job ID '%s' already in use", job_id);
-            return NULL;
-        }
-    }
-
-    blk = blk_new(perm, shared_perm);
-    ret = blk_insert_bs(blk, bs, errp);
-    if (ret < 0) {
-        blk_unref(blk);
-        return NULL;
-    }
-
-    job = g_malloc0(driver->instance_size);
-    job->driver        = driver;
-    job->id            = g_strdup(job_id);
-    job->blk           = blk;
-    job->cb            = cb;
-    job->opaque        = opaque;
-    job->busy          = false;
-    job->paused        = true;
-    job->pause_count   = 1;
-    job->refcnt        = 1;
-
-    error_setg(&job->blocker, "block device is in use by block job: %s",
-               BlockJobType_lookup[driver->job_type]);
-    block_job_add_bdrv(job, "main node", bs, 0, BLK_PERM_ALL, &error_abort);
-    bs->job = job;
-
-    blk_set_dev_ops(blk, &block_job_dev_ops, job);
-    bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker);
-
-    QLIST_INSERT_HEAD(&block_jobs, job, job_list);
-
-    blk_add_aio_context_notifier(blk, block_job_attached_aio_context,
-                                 block_job_detach_aio_context, job);
-
-    /* Only set speed when necessary to avoid NotSupported error */
-    if (speed != 0) {
-        Error *local_err = NULL;
-
-        block_job_set_speed(job, speed, &local_err);
-        if (local_err) {
-            block_job_unref(job);
-            error_propagate(errp, local_err);
-            return NULL;
-        }
-    }
-    return job;
-}
-
 bool block_job_is_internal(BlockJob *job)
 {
     return (job->id == NULL);
@@ -XXX,XX +XXX,XX @@ void block_job_start(BlockJob *job)
     bdrv_coroutine_enter(blk_bs(job->blk), job->co);
 }
 
-void block_job_early_fail(BlockJob *job)
-{
-    block_job_unref(job);
-}
-
 static void block_job_completed_single(BlockJob *job)
 {
     if (!job->ret) {
@@ -XXX,XX +XXX,XX @@ static void block_job_completed_txn_success(BlockJob *job)
     }
 }
 
-void block_job_completed(BlockJob *job, int ret)
-{
-    assert(blk_bs(job->blk)->job == job);
-    assert(!job->completed);
-    job->completed = true;
-    job->ret = ret;
-    if (!job->txn) {
-        block_job_completed_single(job);
-    } else if (ret < 0 || block_job_is_cancelled(job)) {
-        block_job_completed_txn_abort(job);
-    } else {
-        block_job_completed_txn_success(job);
-    }
-}
-
 void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
 {
     Error *local_err = NULL;
@@ -XXX,XX +XXX,XX @@ void block_job_user_pause(BlockJob *job)
     block_job_pause(job);
 }
 
-static bool block_job_should_pause(BlockJob *job)
-{
-    return job->pause_count > 0;
-}
-
 bool block_job_user_paused(BlockJob *job)
 {
     return job->user_paused;
 }
 
-void coroutine_fn block_job_pause_point(BlockJob *job)
-{
-    assert(job && block_job_started(job));
-
-    if (!block_job_should_pause(job)) {
-        return;
-    }
-    if (block_job_is_cancelled(job)) {
-        return;
-    }
-
-    if (job->driver->pause) {
-        job->driver->pause(job);
-    }
-
-    if (block_job_should_pause(job) && !block_job_is_cancelled(job)) {
-        job->paused = true;
-        job->busy = false;
-        qemu_coroutine_yield(); /* wait for block_job_resume() */
-        job->busy = true;
-        job->paused = false;
-    }
-
-    if (job->driver->resume) {
-        job->driver->resume(job);
-    }
-}
-
 void block_job_user_resume(BlockJob *job)
 {
     if (job && job->user_paused && job->pause_count > 0) {
@@ -XXX,XX +XXX,XX @@ void block_job_user_resume(BlockJob *job)
     }
 }
 
-void block_job_enter(BlockJob *job)
-{
-    if (job->co && !job->busy) {
-        bdrv_coroutine_enter(blk_bs(job->blk), job->co);
-    }
-}
-
 void block_job_cancel(BlockJob *job)
 {
     if (block_job_started(job)) {
@@ -XXX,XX +XXX,XX @@ void block_job_cancel(BlockJob *job)
     }
 }
 
-bool block_job_is_cancelled(BlockJob *job)
-{
-    return job->cancelled;
-}
-
 void block_job_iostatus_reset(BlockJob *job)
 {
     job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
@@ -XXX,XX +XXX,XX @@ int block_job_complete_sync(BlockJob *job, Error **errp)
     return block_job_finish_sync(job, &block_job_complete, errp);
 }
 
-void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns)
-{
-    assert(job->busy);
-
-    /* Check cancellation *before* setting busy = false, too!  */
-    if (block_job_is_cancelled(job)) {
-        return;
-    }
-
-    job->busy = false;
-    if (!block_job_should_pause(job)) {
-        co_aio_sleep_ns(blk_get_aio_context(job->blk), type, ns);
-    }
-    job->busy = true;
-
-    block_job_pause_point(job);
-}
-
-void block_job_yield(BlockJob *job)
-{
-    assert(job->busy);
-
-    /* Check cancellation *before* setting busy = false, too!  */
-    if (block_job_is_cancelled(job)) {
-        return;
-    }
-
-    job->busy = false;
-    if (!block_job_should_pause(job)) {
-        qemu_coroutine_yield();
-    }
-    job->busy = true;
-
-    block_job_pause_point(job);
-}
-
 BlockJobInfo *block_job_query(BlockJob *job, Error **errp)
 {
     BlockJobInfo *info;
@@ -XXX,XX +XXX,XX @@ static void block_job_event_completed(BlockJob *job, const char *msg)
                                         &error_abort);
 }
 
+/*
+ * API for block job drivers and the block layer.  These functions are
+ * declared in blockjob_int.h.
+ */
+
+void *block_job_create(const char *job_id, const BlockJobDriver *driver,
+                       BlockDriverState *bs, uint64_t perm,
+                       uint64_t shared_perm, int64_t speed, int flags,
+                       BlockCompletionFunc *cb, void *opaque, Error **errp)
+{
+    BlockBackend *blk;
+    BlockJob *job;
+    int ret;
+
+    if (bs->job) {
+        error_setg(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
+        return NULL;
+    }
+
+    if (job_id == NULL && !(flags & BLOCK_JOB_INTERNAL)) {
+        job_id = bdrv_get_device_name(bs);
+        if (!*job_id) {
+            error_setg(errp, "An explicit job ID is required for this node");
+            return NULL;
+        }
+    }
+
+    if (job_id) {
+        if (flags & BLOCK_JOB_INTERNAL) {
+            error_setg(errp, "Cannot specify job ID for internal block job");
+            return NULL;
+        }
+
+        if (!id_wellformed(job_id)) {
+            error_setg(errp, "Invalid job ID '%s'", job_id);
+            return NULL;
+        }
+
+        if (block_job_get(job_id)) {
+            error_setg(errp, "Job ID '%s' already in use", job_id);
+            return NULL;
+        }
+    }
+
+    blk = blk_new(perm, shared_perm);
+    ret = blk_insert_bs(blk, bs, errp);
+    if (ret < 0) {
+        blk_unref(blk);
+        return NULL;
+    }
+
+    job = g_malloc0(driver->instance_size);
+    job->driver        = driver;
+    job->id            = g_strdup(job_id);
+    job->blk           = blk;
+    job->cb            = cb;
+    job->opaque        = opaque;
+    job->busy          = false;
+    job->paused        = true;
+    job->pause_count   = 1;
+    job->refcnt        = 1;
+
+    error_setg(&job->blocker, "block device is in use by block job: %s",
+               BlockJobType_lookup[driver->job_type]);
+    block_job_add_bdrv(job, "main node", bs, 0, BLK_PERM_ALL, &error_abort);
+    bs->job = job;
+
+    blk_set_dev_ops(blk, &block_job_dev_ops, job);
+    bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker);
+
+    QLIST_INSERT_HEAD(&block_jobs, job, job_list);
+
+    blk_add_aio_context_notifier(blk, block_job_attached_aio_context,
+                                 block_job_detach_aio_context, job);
+
+    /* Only set speed when necessary to avoid NotSupported error */
+    if (speed != 0) {
+        Error *local_err = NULL;
+
+        block_job_set_speed(job, speed, &local_err);
+        if (local_err) {
+            block_job_unref(job);
+            error_propagate(errp, local_err);
+            return NULL;
+        }
+    }
+    return job;
+}
+
 void block_job_pause_all(void)
 {
     BlockJob *job = NULL;
@@ -XXX,XX +XXX,XX @@ void block_job_pause_all(void)
     }
 }
 
+void block_job_early_fail(BlockJob *job)
+{
+    block_job_unref(job);
+}
+
+void block_job_completed(BlockJob *job, int ret)
+{
+    assert(blk_bs(job->blk)->job == job);
+    assert(!job->completed);
+    job->completed = true;
+    job->ret = ret;
+    if (!job->txn) {
+        block_job_completed_single(job);
+    } else if (ret < 0 || block_job_is_cancelled(job)) {
+        block_job_completed_txn_abort(job);
+    } else {
+        block_job_completed_txn_success(job);
+    }
+}
+
+static bool block_job_should_pause(BlockJob *job)
+{
+    return job->pause_count > 0;
+}
+
+void coroutine_fn block_job_pause_point(BlockJob *job)
+{
+    assert(job && block_job_started(job));
+
+    if (!block_job_should_pause(job)) {
+        return;
+    }
+    if (block_job_is_cancelled(job)) {
+        return;
+    }
+
+    if (job->driver->pause) {
+        job->driver->pause(job);
+    }
+
+    if (block_job_should_pause(job) && !block_job_is_cancelled(job)) {
+        job->paused = true;
+        job->busy = false;
+        qemu_coroutine_yield(); /* wait for block_job_resume() */
+        job->busy = true;
+        job->paused = false;
+    }
+
+    if (job->driver->resume) {
+        job->driver->resume(job);
+    }
+}
+
 void block_job_resume_all(void)
 {
     BlockJob *job = NULL;
@@ -XXX,XX +XXX,XX @@ void block_job_resume_all(void)
     }
 }
 
+void block_job_enter(BlockJob *job)
+{
+    if (job->co && !job->busy) {
+        bdrv_coroutine_enter(blk_bs(job->blk), job->co);
+    }
+}
+
+bool block_job_is_cancelled(BlockJob *job)
+{
+    return job->cancelled;
+}
+
+void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns)
+{
+    assert(job->busy);
+
+    /* Check cancellation *before* setting busy = false, too!  */
+    if (block_job_is_cancelled(job)) {
+        return;
+    }
+
+    job->busy = false;
+    if (!block_job_should_pause(job)) {
+        co_aio_sleep_ns(blk_get_aio_context(job->blk), type, ns);
+    }
+    job->busy = true;
+
+    block_job_pause_point(job);
+}
+
+void block_job_yield(BlockJob *job)
+{
+    assert(job->busy);
+
+    /* Check cancellation *before* setting busy = false, too!  */
+    if (block_job_is_cancelled(job)) {
+        return;
+    }
+
+    job->busy = false;
+    if (!block_job_should_pause(job)) {
+        qemu_coroutine_yield();
+    }
+    job->busy = true;
+
+    block_job_pause_point(job);
+}
+
 void block_job_event_ready(BlockJob *job)
 {
     job->ready = true;
-- 
2.9.3

From: Paolo Bonzini <pbonzini@redhat.com>

Outside blockjob.c, the block_job_iostatus_reset function is used once
in the monitor and once in BlockBackend.  When we introduce the block
job mutex, block_job_iostatus_reset's client is going to be the block
layer (for which blockjob.c will take the block job mutex) rather than
the monitor (which will take the block job mutex by itself).

The monitor's call to block_job_iostatus_reset from the monitor comes
just before the sole call to block_job_user_resume, so reset the
iostatus directly from block_job_iostatus_reset.  This will avoid
the need to introduce separate block_job_iostatus_reset and
block_job_iostatus_reset_locked APIs.

After making this change, move the function together with the others
that were moved in the previous patch.

diff --git a/blockdev.c b/blockdev.c
index XXXXXXX..XXXXXXX 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -XXX,XX +XXX,XX @@ void qmp_block_job_resume(const char *device, Error **errp)
     }
 
     trace_qmp_block_job_resume(job);
-    block_job_iostatus_reset(job);
     block_job_user_resume(job);
     aio_context_release(aio_context);
 }
diff --git a/blockjob.c b/blockjob.c
index XXXXXXX..XXXXXXX 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -XXX,XX +XXX,XX @@ void block_job_user_resume(BlockJob *job)
 {
     if (job && job->user_paused && job->pause_count > 0) {
         job->user_paused = false;
+        block_job_iostatus_reset(job);
         block_job_resume(job);
     }
 }
@@ -XXX,XX +XXX,XX @@ void block_job_cancel(BlockJob *job)
     }
 }
 
-void block_job_iostatus_reset(BlockJob *job)
-{
-    job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
-}
-
 static int block_job_finish_sync(BlockJob *job,
                                  void (*finish)(BlockJob *, Error **errp),
                                  Error **errp)
@@ -XXX,XX +XXX,XX @@ void block_job_yield(BlockJob *job)
     block_job_pause_point(job);
 }
 
+void block_job_iostatus_reset(BlockJob *job)
+{
+    job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
+}
+
 void block_job_event_ready(BlockJob *job)
 {
     job->ready = true;
-- 
2.9.3

From: Paolo Bonzini <pbonzini@redhat.com>

The new functions helps respecting the invariant that the coroutine
is entered with false user_resume, zero pause count and no error
recorded in the iostatus.

Resetting the iostatus is now common to all of block_job_cancel_async,
block_job_user_resume and block_job_iostatus_reset, albeit with slight
differences:

- block_job_cancel_async resets the iostatus, and resumes the job if
there was an error, but the coroutine is not restarted immediately.
For example the caller may continue with a call to block_job_finish_sync.

- block_job_user_resume resets the iostatus.  It wants to resume the job
unconditionally, even if there was no error.

- block_job_iostatus_reset doesn't resume the job at all.  Maybe that's
a bug but it should be fixed separately.

block_job_iostatus_reset does the least common denominator, so add some
checking but otherwise leave it as the entry point for resetting the
iostatus.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20170508141310.8674-8-pbonzini@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 blockjob.c | 24 ++++++++++++++++++++----
 1 file changed, 20 insertions(+), 4 deletions(-)

diff --git a/blockjob.c b/blockjob.c
index XXXXXXX..XXXXXXX 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -XXX,XX +XXX,XX @@ static void block_job_completed_single(BlockJob *job)
     block_job_unref(job);
 }
 
+static void block_job_cancel_async(BlockJob *job)
+{
+    if (job->iostatus != BLOCK_DEVICE_IO_STATUS_OK) {
+        block_job_iostatus_reset(job);
+    }
+    if (job->user_paused) {
+        /* Do not call block_job_enter here, the caller will handle it.  */
+        job->user_paused = false;
+        job->pause_count--;
+    }
+    job->cancelled = true;
+}
+
 static void block_job_completed_txn_abort(BlockJob *job)
 {
     AioContext *ctx;
@@ -XXX,XX +XXX,XX @@ static void block_job_completed_txn_abort(BlockJob *job)
              * them; this job, however, may or may not be cancelled, depending
              * on the caller, so leave it. */
             if (other_job != job) {
-                other_job->cancelled = true;
+                block_job_cancel_async(other_job);
             }
             continue;
         }
@@ -XXX,XX +XXX,XX @@ bool block_job_user_paused(BlockJob *job)
 void block_job_user_resume(BlockJob *job)
 {
     if (job && job->user_paused && job->pause_count > 0) {
-        job->user_paused = false;
         block_job_iostatus_reset(job);
+        job->user_paused = false;
         block_job_resume(job);
     }
 }
@@ -XXX,XX +XXX,XX @@ void block_job_user_resume(BlockJob *job)
 void block_job_cancel(BlockJob *job)
 {
     if (block_job_started(job)) {
-        job->cancelled = true;
-        block_job_iostatus_reset(job);
+        block_job_cancel_async(job);
         block_job_enter(job);
     } else {
         block_job_completed(job, -ECANCELED);
@@ -XXX,XX +XXX,XX @@ void block_job_yield(BlockJob *job)
 
 void block_job_iostatus_reset(BlockJob *job)
 {
+    if (job->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
+        return;
+    }
+    assert(job->user_paused && job->pause_count > 0);
     job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
 }
 
-- 
2.9.3

From: Paolo Bonzini <pbonzini@redhat.com>

Yet another pure code movement patch, preparing for the next change.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20170508141310.8674-9-pbonzini@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 blockjob.c | 128 ++++++++++++++++++++++++++++++-------------------------------
 1 file changed, 64 insertions(+), 64 deletions(-)

diff --git a/blockjob.c b/blockjob.c
index XXXXXXX..XXXXXXX 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -XXX,XX +XXX,XX @@ BlockJob *block_job_get(const char *id)
     return NULL;
 }
 
+BlockJobTxn *block_job_txn_new(void)
+{
+    BlockJobTxn *txn = g_new0(BlockJobTxn, 1);
+    QLIST_INIT(&txn->jobs);
+    txn->refcnt = 1;
+    return txn;
+}
+
+static void block_job_txn_ref(BlockJobTxn *txn)
+{
+    txn->refcnt++;
+}
+
+void block_job_txn_unref(BlockJobTxn *txn)
+{
+    if (txn && --txn->refcnt == 0) {
+        g_free(txn);
+    }
+}
+
+void block_job_txn_add_job(BlockJobTxn *txn, BlockJob *job)
+{
+    if (!txn) {
+        return;
+    }
+
+    assert(!job->txn);
+    job->txn = txn;
+
+    QLIST_INSERT_HEAD(&txn->jobs, job, txn_list);
+    block_job_txn_ref(txn);
+}
+
 static void block_job_pause(BlockJob *job)
 {
     job->pause_count++;
@@ -XXX,XX +XXX,XX @@ static void block_job_cancel_async(BlockJob *job)
     job->cancelled = true;
 }
 
+static int block_job_finish_sync(BlockJob *job,
+                                 void (*finish)(BlockJob *, Error **errp),
+                                 Error **errp)
+{
+    Error *local_err = NULL;
+    int ret;
+
+    assert(blk_bs(job->blk)->job == job);
+
+    block_job_ref(job);
+
+    finish(job, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        block_job_unref(job);
+        return -EBUSY;
+    }
+    /* block_job_drain calls block_job_enter, and it should be enough to
+     * induce progress until the job completes or moves to the main thread.
+    */
+    while (!job->deferred_to_main_loop && !job->completed) {
+        block_job_drain(job);
+    }
+    while (!job->completed) {
+        aio_poll(qemu_get_aio_context(), true);
+    }
+    ret = (job->cancelled && job->ret == 0) ? -ECANCELED : job->ret;
+    block_job_unref(job);
+    return ret;
+}
+
 static void block_job_completed_txn_abort(BlockJob *job)
 {
     AioContext *ctx;
@@ -XXX,XX +XXX,XX @@ void block_job_cancel(BlockJob *job)
     }
 }
 
-static int block_job_finish_sync(BlockJob *job,
-                                 void (*finish)(BlockJob *, Error **errp),
-                                 Error **errp)
-{
-    Error *local_err = NULL;
-    int ret;
-
-    assert(blk_bs(job->blk)->job == job);
-
-    block_job_ref(job);
-
-    finish(job, &local_err);
-    if (local_err) {
-        error_propagate(errp, local_err);
-        block_job_unref(job);
-        return -EBUSY;
-    }
-    /* block_job_drain calls block_job_enter, and it should be enough to
-     * induce progress until the job completes or moves to the main thread.
-    */
-    while (!job->deferred_to_main_loop && !job->completed) {
-        block_job_drain(job);
-    }
-    while (!job->completed) {
-        aio_poll(qemu_get_aio_context(), true);
-    }
-    ret = (job->cancelled && job->ret == 0) ? -ECANCELED : job->ret;
-    block_job_unref(job);
-    return ret;
-}
-
 /* A wrapper around block_job_cancel() taking an Error ** parameter so it may be
  * used with block_job_finish_sync() without the need for (rather nasty)
  * function pointer casts there. */
@@ -XXX,XX +XXX,XX @@ void block_job_defer_to_main_loop(BlockJob *job,
     aio_bh_schedule_oneshot(qemu_get_aio_context(),
                             block_job_defer_to_main_loop_bh, data);
 }
-
-BlockJobTxn *block_job_txn_new(void)
-{
-    BlockJobTxn *txn = g_new0(BlockJobTxn, 1);
-    QLIST_INIT(&txn->jobs);
-    txn->refcnt = 1;
-    return txn;
-}
-
-static void block_job_txn_ref(BlockJobTxn *txn)
-{
-    txn->refcnt++;
-}
-
-void block_job_txn_unref(BlockJobTxn *txn)
-{
-    if (txn && --txn->refcnt == 0) {
-        g_free(txn);
-    }
-}
-
-void block_job_txn_add_job(BlockJobTxn *txn, BlockJob *job)
-{
-    if (!txn) {
-        return;
-    }
-
-    assert(!job->txn);
-    job->txn = txn;
-
-    QLIST_INSERT_HEAD(&txn->jobs, job, txn_list);
-    block_job_txn_ref(txn);
-}
-- 
2.9.3

From: Paolo Bonzini <pbonzini@redhat.com>

Unlike test-blockjob-txn, QMP releases the reference to the transaction
before the jobs finish.  Thus, qemu-iotest 124 showed a failure while
working on the next patch that the unit tests did not have.  Make
the test a little nastier.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20170508141310.8674-10-pbonzini@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 tests/test-blockjob-txn.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tests/test-blockjob-txn.c b/tests/test-blockjob-txn.c
index XXXXXXX..XXXXXXX 100644
--- a/tests/test-blockjob-txn.c
+++ b/tests/test-blockjob-txn.c
@@ -XXX,XX +XXX,XX @@ static void test_pair_jobs(int expected1, int expected2)
     block_job_start(job1);
     block_job_start(job2);
 
+    /* Release our reference now to trigger as many nice
+     * use-after-free bugs as possible.
+     */
+    block_job_txn_unref(txn);
+
     if (expected1 == -ECANCELED) {
         block_job_cancel(job1);
     }
@@ -XXX,XX +XXX,XX @@ static void test_pair_jobs(int expected1, int expected2)
 
     g_assert_cmpint(result1, ==, expected1);
     g_assert_cmpint(result2, ==, expected2);
-
-    block_job_txn_unref(txn);
 }
 
 static void test_pair_jobs_success(void)
-- 
2.9.3

From: Paolo Bonzini <pbonzini@redhat.com>

This splits the part that touches job states from the part that invokes
callbacks.  It will make the code simpler to understand once job states will
be protected by a different mutex than the AioContext lock.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20170508141310.8674-11-pbonzini@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 blockjob.c | 35 ++++++++++++++++++++++-------------
 1 file changed, 22 insertions(+), 13 deletions(-)

diff --git a/blockjob.c b/blockjob.c
index XXXXXXX..XXXXXXX 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -XXX,XX +XXX,XX @@ void block_job_start(BlockJob *job)
 
 static void block_job_completed_single(BlockJob *job)
 {
+    assert(job->completed);
+
     if (!job->ret) {
         if (job->driver->commit) {
             job->driver->commit(job);
@@ -XXX,XX +XXX,XX @@ static int block_job_finish_sync(BlockJob *job,
 
     block_job_ref(job);
 
-    finish(job, &local_err);
+    if (finish) {
+        finish(job, &local_err);
+    }
     if (local_err) {
         error_propagate(errp, local_err);
         block_job_unref(job);
@@ -XXX,XX +XXX,XX @@ static void block_job_completed_txn_abort(BlockJob *job)
 {
     AioContext *ctx;
     BlockJobTxn *txn = job->txn;
-    BlockJob *other_job, *next;
+    BlockJob *other_job;
 
     if (txn->aborting) {
         /*
@@ -XXX,XX +XXX,XX @@ static void block_job_completed_txn_abort(BlockJob *job)
         return;
     }
     txn->aborting = true;
+    block_job_txn_ref(txn);
+
     /* We are the first failed job. Cancel other jobs. */
     QLIST_FOREACH(other_job, &txn->jobs, txn_list) {
         ctx = blk_get_aio_context(other_job->blk);
         aio_context_acquire(ctx);
     }
+
+    /* Other jobs are effectively cancelled by us, set the status for
+     * them; this job, however, may or may not be cancelled, depending
+     * on the caller, so leave it. */
     QLIST_FOREACH(other_job, &txn->jobs, txn_list) {
-        if (other_job == job || other_job->completed) {
-            /* Other jobs are "effectively" cancelled by us, set the status for
-             * them; this job, however, may or may not be cancelled, depending
-             * on the caller, so leave it. */
-            if (other_job != job) {
-                block_job_cancel_async(other_job);
-            }
-            continue;
+        if (other_job != job) {
+            block_job_cancel_async(other_job);
         }
-        block_job_cancel_sync(other_job);
-        assert(other_job->completed);
     }
-    QLIST_FOREACH_SAFE(other_job, &txn->jobs, txn_list, next) {
+    while (!QLIST_EMPTY(&txn->jobs)) {
+        other_job = QLIST_FIRST(&txn->jobs);
         ctx = blk_get_aio_context(other_job->blk);
+        if (!other_job->completed) {
+            assert(other_job->cancelled);
+            block_job_finish_sync(other_job, NULL, NULL);
+        }
         block_job_completed_single(other_job);
         aio_context_release(ctx);
     }
+
+    block_job_txn_unref(txn);
 }
 
 static void block_job_completed_txn_success(BlockJob *job)
-- 
2.9.3

From: Paolo Bonzini <pbonzini@redhat.com>

All block jobs are using block_job_defer_to_main_loop as the final
step just before the coroutine terminates.  At this point,
block_job_enter should do nothing, but currently it restarts
the freed coroutine.

Now, the job->co states should probably be changed to an enum
(e.g. BEFORE_START, STARTED, YIELDED, COMPLETED) subsuming
block_job_started, job->deferred_to_main_loop and job->busy.
For now, this patch eliminates the problematic reenter by
removing the reset of job->deferred_to_main_loop (which served
no purpose, as far as I could see) and checking the flag in
block_job_enter.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20170508141310.8674-12-pbonzini@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 blockjob.c                   | 10 ++++++++--
 include/block/blockjob_int.h |  3 ++-
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/blockjob.c b/blockjob.c
index XXXXXXX..XXXXXXX 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -XXX,XX +XXX,XX @@ void block_job_resume_all(void)
 
 void block_job_enter(BlockJob *job)
 {
-    if (job->co && !job->busy) {
+    if (!block_job_started(job)) {
+        return;
+    }
+    if (job->deferred_to_main_loop) {
+        return;
+    }
+
+    if (!job->busy) {
         bdrv_coroutine_enter(blk_bs(job->blk), job->co);
     }
 }
@@ -XXX,XX +XXX,XX @@ static void block_job_defer_to_main_loop_bh(void *opaque)
         aio_context_acquire(aio_context);
     }
 
-    data->job->deferred_to_main_loop = false;
     data->fn(data->job, data->opaque);
 
     if (aio_context != data->aio_context) {
diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h
index XXXXXXX..XXXXXXX 100644
--- a/include/block/blockjob_int.h
+++ b/include/block/blockjob_int.h
@@ -XXX,XX +XXX,XX @@ typedef void BlockJobDeferToMainLoopFn(BlockJob *job, void *opaque);
  * @fn: The function to run in the main loop
  * @opaque: The opaque value that is passed to @fn
  *
- * Execute a given function in the main loop with the BlockDriverState
+ * This function must be called by the main job coroutine just before it
+ * returns.  @fn is executed in the main loop with the BlockDriverState
  * AioContext acquired.  Block jobs must call bdrv_unref(), bdrv_close(), and
  * anything that uses bdrv_drain_all() in the main loop.
  *
-- 
2.9.3

On current released versions of glusterfs, glfs_lseek() will sometimes
return invalid values for SEEK_DATA or SEEK_HOLE.  For SEEK_DATA and
SEEK_HOLE, the returned value should be >= the passed offset, or < 0 in
the case of error:

LSEEK(2):

off_t lseek(int fd, off_t offset, int whence);

[...]

SEEK_HOLE
              Adjust  the file offset to the next hole in the file greater
              than or equal to offset.  If offset points into the middle of
              a hole, then the file offset is set to offset.  If there is no
              hole past offset, then the file offset is adjusted to the end
              of the file (i.e., there is  an implicit hole at the end of
              any file).

[...]

RETURN VALUE
              Upon  successful  completion,  lseek()  returns  the resulting
              offset location as measured in bytes from the beginning of the
              file.  On error, the value (off_t) -1 is returned and errno is
              set to indicate the error

However, occasionally glfs_lseek() for SEEK_HOLE/DATA will return a
value less than the passed offset, yet greater than zero.

For instance, here are example values observed from this call:

offs = glfs_lseek(s->fd, start, SEEK_HOLE);
    if (offs < 0) {
        return -errno;          /* D1 and (H3 or H4) */
    }

start == 7608336384
offs == 7607877632

This causes QEMU to abort on the assert test.  When this value is
returned, errno is also 0.

This is a reported and known bug to glusterfs:
https://bugzilla.redhat.com/show_bug.cgi?id=1425293

Although this is being fixed in gluster, we still should work around it
in QEMU, given that multiple released versions of gluster behave this
way.

This patch treats the return case of (offs < start) the same as if an
error value other than ENXIO is returned; we will assume we learned
nothing, and there are no holes in the file.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>
Message-id: 87c0140e9407c08f6e74b04131b610f2e27c014c.1495560397.git.jcody@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/gluster.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/block/gluster.c b/block/gluster.c
index XXXXXXX..XXXXXXX 100644
--- a/block/gluster.c
+++ b/block/gluster.c
@@ -XXX,XX +XXX,XX @@ static int find_allocation(BlockDriverState *bs, off_t start,
     if (offs < 0) {
         return -errno;          /* D3 or D4 */
     }
-    assert(offs >= start);
+
+    if (offs < start) {
+        /* This is not a valid return by lseek().  We are safe to just return
+         * -EIO in this case, and we'll treat it like D4. Unfortunately some
+         *  versions of gluster server will return offs < start, so an assert
+         *  here will unnecessarily abort QEMU. */
+        return -EIO;
+    }
 
     if (offs > start) {
         /* D2: in hole, next data at offs */
@@ -XXX,XX +XXX,XX @@ static int find_allocation(BlockDriverState *bs, off_t start,
     if (offs < 0) {
         return -errno;          /* D1 and (H3 or H4) */
     }
-    assert(offs >= start);
+
+    if (offs < start) {
+        /* This is not a valid return by lseek().  We are safe to just return
+         * -EIO in this case, and we'll treat it like H4. Unfortunately some
+         *  versions of gluster server will return offs < start, so an assert
+         *  here will unnecessarily abort QEMU. */
+        return -EIO;
+    }
 
     if (offs > start) {
         /*
-- 
2.9.3

When the request free list is exhausted the coroutine waits on
q->free_req_queue for the next free request. Whenever a request is
completed a BH is scheduled to invoke nvme_free_req_queue_cb() and wake
up waiting coroutines.

1. nvme_get_free_req() waits for a free request:

while (q->free_req_head == -1) {
        ...
            trace_nvme_free_req_queue_wait(q->s, q->index);
            qemu_co_queue_wait(&q->free_req_queue, &q->lock);
        ...
    }

2. nvme_free_req_queue_cb() wakes up the coroutine:

while (qemu_co_enter_next(&q->free_req_queue, &q->lock)) {
       ^--- infinite loop when free_req_head == -1
    }

nvme_free_req_queue_cb() and the coroutine form an infinite loop when
q->free_req_head == -1. Fix this by checking q->free_req_head in
nvme_free_req_queue_cb(). If the free request list is exhausted, don't
wake waiting coroutines. Eventually an in-flight request will complete
and the BH will be scheduled again, guaranteeing forward progress.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20211208152246.244585-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/nvme.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

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 @@ static void nvme_free_req_queue_cb(void *opaque)
     NVMeQueuePair *q = opaque;
 
     qemu_mutex_lock(&q->lock);
-    while (qemu_co_enter_next(&q->free_req_queue, &q->lock)) {
-        /* Retry all pending requests */
+    while (q->free_req_head != -1 &&
+           qemu_co_enter_next(&q->free_req_queue, &q->lock)) {
+        /* Retry waiting requests */
     }
     qemu_mutex_unlock(&q->lock);
 }
-- 
2.33.1