Series comparison

-[Qemu-devel] [PULL 0/4] Block patches
+[PULL 0/1] Block patches
-The following changes since commit 19b599f7664b2ebfd0f405fb79c14dd241557452:
+The following changes since commit 887cba855bb6ff4775256f7968409281350b568c:
-  Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2018-08-27-v2' into staging (2018-08-27 16:44:20 +0100)
+  configure: Fix cross-building for RISCV host (v5) (2023-07-11 17:56:09 +0100)
 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 8af2eb7b43a1b694fd6d1d090025027d6b72caac:
+for you to fetch changes up to 75dcb4d790bbe5327169fd72b185960ca58e2fa6:
-  block/rbd: add deprecation documentation for filename keyvalue pairs (2018-09-12 08:51:45 -0400)
+  virtio-blk: fix host notifier issues during dataplane start/stop (2023-07-12 15:20:32 -0400)
 ----------------------------------------------------------------
-Block patches for RBD
+Pull request
 ----------------------------------------------------------------
-Jeff Cody (4):
+Stefan Hajnoczi (1):
-  block/rbd: pull out qemu_rbd_convert_options
+  virtio-blk: fix host notifier issues during dataplane start/stop
   block/rbd: Attempt to parse legacy filenames
   block/rbd: add iotest for rbd legacy keyvalue filename parsing
   block/rbd: add deprecation documentation for filename keyvalue pairs
- block/rbd.c                | 89 ++++++++++++++++++++++++++++++++------
+ hw/block/dataplane/virtio-blk.c | 67 +++++++++++++++++++--------------
- qemu-deprecated.texi       | 15 +++++++
+file changed, 38 insertions(+), 29 deletions(-)
  tests/qemu-iotests/231     | 62 ++++++++++++++++++++++++++
  tests/qemu-iotests/231.out |  9 ++++
  tests/qemu-iotests/group   |  1 +
 files changed, 162 insertions(+), 14 deletions(-)
  create mode 100755 tests/qemu-iotests/231
  create mode 100644 tests/qemu-iotests/231.out
 --
-.17.1
+.40.1

-[Qemu-devel] [PULL 1/4] block/rbd: pull out qemu_rbd_convert_options
+[PULL 1/1] virtio-blk: fix host notifier issues during dataplane start/stop
-Code movement to pull the conversion from Qdict to BlockdevOptionsRbd
+The main loop thread can consume 100% CPU when using --device
-into a helper function.
+virtio-blk-pci,iothread=<iothread>. ppoll() constantly returns but
 reading virtqueue host notifiers fails with EAGAIN. The file descriptors
 are stale and remain registered with the AioContext because of bugs in
 the virtio-blk dataplane start/stop code.
-Reviewed-by: Eric Blake <eblake@redhat.com>
+The problem is that the dataplane start/stop code involves drain
-Reviewed-by: John Snow <jsnow@redhat.com>
+operations, which call virtio_blk_drained_begin() and
-Signed-off-by: Jeff Cody <jcody@redhat.com>
+virtio_blk_drained_end() at points where the host notifier is not
-Message-id: 5b49a980f2cde6610ab1df41bb0277d00b5db893.1536704901.git.jcody@redhat.com
+operational:
-Signed-off-by: Jeff Cody <jcody@redhat.com>
+- In virtio_blk_data_plane_start(), blk_set_aio_context() drains after
   vblk->dataplane_started has been set to true but the host notifier has
   not been attached yet.
 - In virtio_blk_data_plane_stop(), blk_drain() and blk_set_aio_context()
   drain after the host notifier has already been detached but with
   vblk->dataplane_started still set to true.
 I would like to simplify ->ioeventfd_start/stop() to avoid interactions
 with drain entirely, but couldn't find a way to do that. Instead, this
 patch accepts the fragile nature of the code and reorders it so that
 vblk->dataplane_started is false during drain operations. This way the
 virtio_blk_drained_begin() and virtio_blk_drained_end() calls don't
 touch the host notifier. The result is that
 virtio_blk_data_plane_start() and virtio_blk_data_plane_stop() have
 complete control over the host notifier and stale file descriptors are
 no longer left in the AioContext.
 This patch fixes the 100% CPU consumption in the main loop thread and
 correctly moves host notifier processing to the IOThread.
 Fixes: 1665d9326fd2 ("virtio-blk: implement BlockDevOps->drained_begin()")
 Reported-by: Lukáš Doktor <ldoktor@redhat.com>
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 Tested-by: Lukas Doktor <ldoktor@redhat.com>
 Message-id: 20230704151527.193586-1-stefanha@redhat.com
 Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
 ---
- block/rbd.c | 36 ++++++++++++++++++++++++------------
+ hw/block/dataplane/virtio-blk.c | 67 +++++++++++++++++++--------------
-file changed, 24 insertions(+), 12 deletions(-)
+file changed, 38 insertions(+), 29 deletions(-)
-diff --git a/block/rbd.c b/block/rbd.c
+diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
 index XXXXXXX..XXXXXXX 100644
---- a/block/rbd.c
+--- a/hw/block/dataplane/virtio-blk.c
-+++ b/block/rbd.c
++++ b/hw/block/dataplane/virtio-blk.c
-@@ -XXX,XX +XXX,XX @@ failed_opts:
+@@ -XXX,XX +XXX,XX @@ int virtio_blk_data_plane_start(VirtIODevice *vdev)
-     return r;
      memory_region_transaction_commit();
 -    /*
 -     * These fields are visible to the IOThread so we rely on implicit barriers
 -     * in aio_context_acquire() on the write side and aio_notify_accept() on
 -     * the read side.
 -     */
 -    s->starting = false;
 -    vblk->dataplane_started = true;
      trace_virtio_blk_data_plane_start(s);
      old_context = blk_get_aio_context(s->conf->conf.blk);
@@ -XXX,XX +XXX,XX @@ int virtio_blk_data_plane_start(VirtIODevice *vdev)
          event_notifier_set(virtio_queue_get_host_notifier(vq));
      }
 +    /*
 +     * These fields must be visible to the IOThread when it processes the
 +     * virtqueue, otherwise it will think dataplane has not started yet.
 +     *
 +     * Make sure ->dataplane_started is false when blk_set_aio_context() is
 +     * called above so that draining does not cause the host notifier to be
 +     * detached/attached prematurely.
 +     */
 +    s->starting = false;
 +    vblk->dataplane_started = true;
 +    smp_wmb(); /* paired with aio_notify_accept() on the read side */
 +
      /* Get this show started by hooking up our callbacks */
      if (!blk_in_drain(s->conf->conf.blk)) {
          aio_context_acquire(s->ctx);
@@ -XXX,XX +XXX,XX @@ int virtio_blk_data_plane_start(VirtIODevice *vdev)
    fail_guest_notifiers:
      vblk->dataplane_disabled = true;
      s->starting = false;
 -    vblk->dataplane_started = true;
      return -ENOSYS;
  }
-+static int qemu_rbd_convert_options(QDict *options, BlockdevOptionsRbd **opts,
+@@ -XXX,XX +XXX,XX @@ void virtio_blk_data_plane_stop(VirtIODevice *vdev)
-+                                    Error **errp)
+         aio_wait_bh_oneshot(s->ctx, virtio_blk_data_plane_stop_bh, s);
-+{
+     }
-+    Visitor *v;
-+    Error *local_err = NULL;
++    /*
 +     * Batch all the host notifiers in a single transaction to avoid
 +     * quadratic time complexity in address_space_update_ioeventfds().
 +     */
 +    memory_region_transaction_begin();
 +
-+    /* Convert the remaining options into a QAPI object */
++    for (i = 0; i < nvqs; i++) {
-+    v = qobject_input_visitor_new_flat_confused(options, errp);
++        virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), i, false);
 +    if (!v) {
 +        return -EINVAL;
 +    }
 +
-+    visit_type_BlockdevOptionsRbd(v, NULL, opts, &local_err);
++    /*
-+    visit_free(v);
++     * The transaction expects the ioeventfds to be open when it
 +     * commits. Do it now, before the cleanup loop.
 +     */
 +    memory_region_transaction_commit();
 +
-+    if (local_err) {
++    for (i = 0; i < nvqs; i++) {
-+        error_propagate(errp, local_err);
++        virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), i);
 +        return -EINVAL;
 +    }
 +
-+    return 0;
++    /*
-+}
++     * Set ->dataplane_started to false before draining so that host notifiers
 +     * are not detached/attached anymore.
 +     */
 +    vblk->dataplane_started = false;
 +
- static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
+     aio_context_acquire(s->ctx);
-                          Error **errp)
- {
+     /* Wait for virtio_blk_dma_restart_bh() and in flight I/O to complete */
-     BDRVRBDState *s = bs->opaque;
+@@ -XXX,XX +XXX,XX @@ void virtio_blk_data_plane_stop(VirtIODevice *vdev)
-     BlockdevOptionsRbd *opts = NULL;
--    Visitor *v;
+     aio_context_release(s->ctx);
-     const QDictEntry *e;
-     Error *local_err = NULL;
+-    /*
-     char *keypairs, *secretid;
+-     * Batch all the host notifiers in a single transaction to avoid
-@@ -XXX,XX +XXX,XX @@ static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
+-     * quadratic time complexity in address_space_update_ioeventfds().
-         qdict_del(options, "password-secret");
+-     */
-     }
+-    memory_region_transaction_begin();
+-
--    /* Convert the remaining options into a QAPI object */
+-    for (i = 0; i < nvqs; i++) {
--    v = qobject_input_visitor_new_flat_confused(options, errp);
+-        virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), i, false);
 -    if (!v) {
 -        r = -EINVAL;
 -        goto out;
 -    }
 -
--    visit_type_BlockdevOptionsRbd(v, NULL, &opts, &local_err);
+-    /*
--    visit_free(v);
+-     * The transaction expects the ioeventfds to be open when it
 -     * commits. Do it now, before the cleanup loop.
 -     */
 -    memory_region_transaction_commit();
 -
-+    r = qemu_rbd_convert_options(options, &opts, &local_err);
+-    for (i = 0; i < nvqs; i++) {
-     if (local_err) {
+-        virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), i);
-         error_propagate(errp, local_err);
+-    }
--        r = -EINVAL;
+-
-         goto out;
+     qemu_bh_cancel(s->bh);
-     }
+     notify_guest_bh(s); /* final chance to notify guest */
      /* Clean up guest notifier (irq) */
      k->set_guest_notifiers(qbus->parent, nvqs, false);
 -    vblk->dataplane_started = false;
      s->stopping = false;
  }
 --
-.17.1
+.40.1

-[Qemu-devel] [PULL 2/4] block/rbd: Attempt to parse legacy filenames
+Deleted patch
-When we converted rbd to get rid of the older key/value-centric
-encoding format, we broke compatibility with image files with backing
-file strings encoded in the old format.
-This leaves a bit of an ugly conundrum, and a hacky solution.
-If the initial attempt to parse the "proper" options fails, it assumes
-that we may have an older key/value encoded filename.  Fall back to
-attempting to parse the filename, and extract the required options from
-it.  If that fails, pass along the original error message.
-We do not support mixed modern usage alongside legacy keyvalue pair
-usage.
-A deprecation warning has been added, although care should be taken
-when actually deprecating since the impact is not limited to
-commandline or qapi usage, but also opening existing images.
-Reviewed-by: Eric Blake <eblake@redhat.com>
-Signed-off-by: Jeff Cody <jcody@redhat.com>
-Message-id: 15b332e5432ad069441f7275a46080f465d789a0.1536704901.git.jcody@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- block/rbd.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++--
-file changed, 51 insertions(+), 2 deletions(-)
-diff --git a/block/rbd.c b/block/rbd.c
-index XXXXXXX..XXXXXXX 100644
---- a/block/rbd.c
-+++ b/block/rbd.c
-@@ -XXX,XX +XXX,XX @@ static int qemu_rbd_convert_options(QDict *options, BlockdevOptionsRbd **opts,
-     return 0;
- }
-+static int qemu_rbd_attempt_legacy_options(QDict *options,
-+                                           BlockdevOptionsRbd **opts,
-+                                           char **keypairs)
-+{
-+    char *filename;
-+    int r;
-+
-+    filename = g_strdup(qdict_get_try_str(options, "filename"));
-+    if (!filename) {
-+        return -EINVAL;
-+    }
-+    qdict_del(options, "filename");
-+
-+    qemu_rbd_parse_filename(filename, options, NULL);
-+
-+    /* keypairs freed by caller */
-+    *keypairs = g_strdup(qdict_get_try_str(options, "=keyvalue-pairs"));
-+    if (*keypairs) {
-+        qdict_del(options, "=keyvalue-pairs");
-+    }
-+
-+    r = qemu_rbd_convert_options(options, opts, NULL);
-+
-+    g_free(filename);
-+    return r;
-+}
-+
- static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
-                          Error **errp)
- {
-@@ -XXX,XX +XXX,XX @@ static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
-     r = qemu_rbd_convert_options(options, &opts, &local_err);
-     if (local_err) {
--        error_propagate(errp, local_err);
--        goto out;
-+        /* If keypairs are present, that means some options are present in
-+         * the modern option format.  Don't attempt to parse legacy option
-+         * formats, as we won't support mixed usage. */
-+        if (keypairs) {
-+            error_propagate(errp, local_err);
-+            goto out;
-+        }
-+
-+        /* If the initial attempt to convert and process the options failed,
-+         * we may be attempting to open an image file that has the rbd options
-+         * specified in the older format consisting of all key/value pairs
-+         * encoded in the filename.  Go ahead and attempt to parse the
-+         * filename, and see if we can pull out the required options. */
-+        r = qemu_rbd_attempt_legacy_options(options, &opts, &keypairs);
-+        if (r < 0) {
-+            error_propagate(errp, local_err);
-+            goto out;
-+        }
-+        /* Take care whenever deciding to actually deprecate; once this ability
-+         * is removed, we will not be able to open any images with legacy-styled
-+         * backing image strings. */
-+        error_report("RBD options encoded in the filename as keyvalue pairs "
-+                     "is deprecated.  Future versions may cease to parse "
-+                     "these options in the future.");
-     }
-     /* Remove the processed options from the QDict (the visitor processes
---
-.17.1

-[Qemu-devel] [PULL 3/4] block/rbd: add iotest for rbd legacy keyvalue filename parsing
+Deleted patch
-This is a small test that will check for the ability to parse
-both legacy and modern options for rbd.
-The way the test is set up is for failure to occur, but without
-having to wait to timeout on a non-existent rbd server.  The error
-messages in the success path show that the arguments were parsed.
-The failure behavior prior to the patch series that has this test, is
-qemu-img complaining about mandatory options (e.g. 'pool') not being
-provided.
-Reviewed-by: Eric Blake <eblake@redhat.com>
-Signed-off-by: Jeff Cody <jcody@redhat.com>
-Message-id: f830580e339b974a83ed4870d11adcdc17f49a47.1536704901.git.jcody@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- tests/qemu-iotests/231     | 62 ++++++++++++++++++++++++++++++++++++++
- tests/qemu-iotests/231.out |  9 ++++++
- tests/qemu-iotests/group   |  1 +
-files changed, 72 insertions(+)
- create mode 100755 tests/qemu-iotests/231
- create mode 100644 tests/qemu-iotests/231.out
-diff --git a/tests/qemu-iotests/231 b/tests/qemu-iotests/231
-new file mode 100755
-index XXXXXXX..XXXXXXX
---- /dev/null
-+++ b/tests/qemu-iotests/231
-@@ -XXX,XX +XXX,XX @@
-+#!/bin/bash
-+#
-+# Test legacy and modern option parsing for rbd/ceph.  This will not
-+# actually connect to a ceph server, but rather looks for the appropriate
-+# error message that indicates we parsed the options correctly.
-+#
-+# Copyright (C) 2018 Red Hat, Inc.
-+#
-+# This program is free software; you can redistribute it and/or modify
-+# it under the terms of the GNU General Public License as published by
-+# the Free Software Foundation; either version 2 of the License, or
-+# (at your option) any later version.
-+#
-+# This program is distributed in the hope that it will be useful,
-+# but WITHOUT ANY WARRANTY; without even the implied warranty of
-+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-+# GNU General Public License for more details.
-+#
-+# You should have received a copy of the GNU General Public License
-+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-+#
-+
-+# creator
-+owner=jcody@redhat.com
-+
-+seq=`basename $0`
-+echo "QA output created by $seq"
-+
-+here=`pwd`
-+status=1    # failure is the default!
-+
-+_cleanup()
-+{
-+    rm "${BOGUS_CONF}"
-+}
-+trap "_cleanup; exit \$status" 0 1 2 3 15
-+
-+# get standard environment, filters and checks
-+. ./common.rc
-+. ./common.filter
-+
-+_supported_fmt generic
-+_supported_proto rbd
-+_supported_os Linux
-+
-+BOGUS_CONF=${TEST_DIR}/ceph-$$.conf
-+touch "${BOGUS_CONF}"
-+
-+_filter_conf()
-+{
-+    sed -e "s#$BOGUS_CONF#BOGUS_CONF#g"
-+}
-+
-+# We expect this to fail, with no monitor ip provided and a null conf file.  Just want it
-+# to fail in the right way.
-+$QEMU_IMG info "json:{'file.driver':'rbd','file.filename':'rbd:rbd/bogus:conf=${BOGUS_CONF}'}" 2>&1 | _filter_conf
-+$QEMU_IMG info "json:{'file.driver':'rbd','file.pool':'rbd','file.image':'bogus','file.conf':'${BOGUS_CONF}'}" 2>&1 | _filter_conf
-+
-+# success, all done
-+echo "*** done"
-+rm -f $seq.full
-+status=0
-diff --git a/tests/qemu-iotests/231.out b/tests/qemu-iotests/231.out
-new file mode 100644
-index XXXXXXX..XXXXXXX
---- /dev/null
-+++ b/tests/qemu-iotests/231.out
-@@ -XXX,XX +XXX,XX @@
-+QA output created by 231
-+qemu-img: RBD options encoded in the filename as keyvalue pairs is deprecated.  Future versions may cease to parse these options in the future.
-+unable to get monitor info from DNS SRV with service name: ceph-mon
-+no monitors specified to connect to.
-+qemu-img: Could not open 'json:{'file.driver':'rbd','file.filename':'rbd:rbd/bogus:conf=BOGUS_CONF'}': error connecting: No such file or directory
-+unable to get monitor info from DNS SRV with service name: ceph-mon
-+no monitors specified to connect to.
-+qemu-img: Could not open 'json:{'file.driver':'rbd','file.pool':'rbd','file.image':'bogus','file.conf':'BOGUS_CONF'}': error connecting: No such file or directory
-+*** done
-diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
-index XXXXXXX..XXXXXXX 100644
---- a/tests/qemu-iotests/group
-+++ b/tests/qemu-iotests/group
-@@ -XXX,XX +XXX,XX @@
-auto quick
-auto quick
-auto quick
-+231 auto quick
---
-.17.1

-[Qemu-devel] [PULL 4/4] block/rbd: add deprecation documentation for filename keyvalue pairs
+Deleted patch
-Signed-off-by: Jeff Cody <jcody@redhat.com>
-Message-id: 647f5b5ab7efd8bf567a504c832b1d2d6f719b23.1536704901.git.jcody@redhat.com
-Signed-off-by: Jeff Cody <jcody@redhat.com>
----
- qemu-deprecated.texi | 15 +++++++++++++++
-file changed, 15 insertions(+)
-diff --git a/qemu-deprecated.texi b/qemu-deprecated.texi
-index XXXXXXX..XXXXXXX 100644
---- a/qemu-deprecated.texi
-+++ b/qemu-deprecated.texi
-@@ -XXX,XX +XXX,XX @@ used instead.
- In order to prevent QEMU from automatically opening an image's backing
- chain, use ``"backing": null'' instead.
-+@subsubsection rbd keyvalue pair encoded filenames: "" (since 3.1.0)
-+
-+Options for ``rbd'' should be specified according to its runtime options,
-+like other block drivers.  Legacy parsing of keyvalue pair encoded
-+filenames is useful to open images with the old format for backing files;
-+These image files should be updated to use the current format.
-+
-+Example of legacy encoding:
-+
-+@code{json:@{"file.driver":"rbd", "file.filename":"rbd:rbd/name"@}}
-+
-+The above, converted to the current supported format:
-+
-+@code{json:@{"file.driver":"rbd", "file.pool":"rbd", "file.image":"name"@}}
-+
- @subsection vio-spapr-device device options
- @subsubsection "irq": "" (since 3.0.0)
---
-.17.1

The following changes since commit 19b599f7664b2ebfd0f405fb79c14dd241557452:

Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2018-08-27-v2' into staging (2018-08-27 16:44:20 +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 8af2eb7b43a1b694fd6d1d090025027d6b72caac:

block/rbd: add deprecation documentation for filename keyvalue pairs (2018-09-12 08:51:45 -0400)

----------------------------------------------------------------
Block patches for RBD
----------------------------------------------------------------

Jeff Cody (4):
  block/rbd: pull out qemu_rbd_convert_options
  block/rbd: Attempt to parse legacy filenames
  block/rbd: add iotest for rbd legacy keyvalue filename parsing
  block/rbd: add deprecation documentation for filename keyvalue pairs

block/rbd.c                | 89 ++++++++++++++++++++++++++++++++------
 qemu-deprecated.texi       | 15 +++++++
 tests/qemu-iotests/231     | 62 ++++++++++++++++++++++++++
 tests/qemu-iotests/231.out |  9 ++++
 tests/qemu-iotests/group   |  1 +
 5 files changed, 162 insertions(+), 14 deletions(-)
 create mode 100755 tests/qemu-iotests/231
 create mode 100644 tests/qemu-iotests/231.out

-- 
2.17.1

Code movement to pull the conversion from Qdict to BlockdevOptionsRbd
into a helper function.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Message-id: 5b49a980f2cde6610ab1df41bb0277d00b5db893.1536704901.git.jcody@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/rbd.c | 36 ++++++++++++++++++++++++------------
 1 file changed, 24 insertions(+), 12 deletions(-)

diff --git a/block/rbd.c b/block/rbd.c
index XXXXXXX..XXXXXXX 100644
--- a/block/rbd.c
+++ b/block/rbd.c
@@ -XXX,XX +XXX,XX @@ failed_opts:
     return r;
 }
 
+static int qemu_rbd_convert_options(QDict *options, BlockdevOptionsRbd **opts,
+                                    Error **errp)
+{
+    Visitor *v;
+    Error *local_err = NULL;
+
+    /* Convert the remaining options into a QAPI object */
+    v = qobject_input_visitor_new_flat_confused(options, errp);
+    if (!v) {
+        return -EINVAL;
+    }
+
+    visit_type_BlockdevOptionsRbd(v, NULL, opts, &local_err);
+    visit_free(v);
+
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return -EINVAL;
+    }
+
+    return 0;
+}
+
 static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
                          Error **errp)
 {
     BDRVRBDState *s = bs->opaque;
     BlockdevOptionsRbd *opts = NULL;
-    Visitor *v;
     const QDictEntry *e;
     Error *local_err = NULL;
     char *keypairs, *secretid;
@@ -XXX,XX +XXX,XX @@ static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
         qdict_del(options, "password-secret");
     }
 
-    /* Convert the remaining options into a QAPI object */
-    v = qobject_input_visitor_new_flat_confused(options, errp);
-    if (!v) {
-        r = -EINVAL;
-        goto out;
-    }
-
-    visit_type_BlockdevOptionsRbd(v, NULL, &opts, &local_err);
-    visit_free(v);
-
+    r = qemu_rbd_convert_options(options, &opts, &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
-        r = -EINVAL;
         goto out;
     }
 
-- 
2.17.1

When we converted rbd to get rid of the older key/value-centric
encoding format, we broke compatibility with image files with backing
file strings encoded in the old format.

This leaves a bit of an ugly conundrum, and a hacky solution.

If the initial attempt to parse the "proper" options fails, it assumes
that we may have an older key/value encoded filename.  Fall back to
attempting to parse the filename, and extract the required options from
it.  If that fails, pass along the original error message.

We do not support mixed modern usage alongside legacy keyvalue pair
usage.

A deprecation warning has been added, although care should be taken
when actually deprecating since the impact is not limited to
commandline or qapi usage, but also opening existing images.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Message-id: 15b332e5432ad069441f7275a46080f465d789a0.1536704901.git.jcody@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/rbd.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 51 insertions(+), 2 deletions(-)

diff --git a/block/rbd.c b/block/rbd.c
index XXXXXXX..XXXXXXX 100644
--- a/block/rbd.c
+++ b/block/rbd.c
@@ -XXX,XX +XXX,XX @@ static int qemu_rbd_convert_options(QDict *options, BlockdevOptionsRbd **opts,
     return 0;
 }
 
+static int qemu_rbd_attempt_legacy_options(QDict *options,
+                                           BlockdevOptionsRbd **opts,
+                                           char **keypairs)
+{
+    char *filename;
+    int r;
+
+    filename = g_strdup(qdict_get_try_str(options, "filename"));
+    if (!filename) {
+        return -EINVAL;
+    }
+    qdict_del(options, "filename");
+
+    qemu_rbd_parse_filename(filename, options, NULL);
+
+    /* keypairs freed by caller */
+    *keypairs = g_strdup(qdict_get_try_str(options, "=keyvalue-pairs"));
+    if (*keypairs) {
+        qdict_del(options, "=keyvalue-pairs");
+    }
+
+    r = qemu_rbd_convert_options(options, opts, NULL);
+
+    g_free(filename);
+    return r;
+}
+
 static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
                          Error **errp)
 {
@@ -XXX,XX +XXX,XX @@ static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
 
     r = qemu_rbd_convert_options(options, &opts, &local_err);
     if (local_err) {
-        error_propagate(errp, local_err);
-        goto out;
+        /* If keypairs are present, that means some options are present in
+         * the modern option format.  Don't attempt to parse legacy option
+         * formats, as we won't support mixed usage. */
+        if (keypairs) {
+            error_propagate(errp, local_err);
+            goto out;
+        }
+
+        /* If the initial attempt to convert and process the options failed,
+         * we may be attempting to open an image file that has the rbd options
+         * specified in the older format consisting of all key/value pairs
+         * encoded in the filename.  Go ahead and attempt to parse the
+         * filename, and see if we can pull out the required options. */
+        r = qemu_rbd_attempt_legacy_options(options, &opts, &keypairs);
+        if (r < 0) {
+            error_propagate(errp, local_err);
+            goto out;
+        }
+        /* Take care whenever deciding to actually deprecate; once this ability
+         * is removed, we will not be able to open any images with legacy-styled
+         * backing image strings. */
+        error_report("RBD options encoded in the filename as keyvalue pairs "
+                     "is deprecated.  Future versions may cease to parse "
+                     "these options in the future.");
     }
 
     /* Remove the processed options from the QDict (the visitor processes
-- 
2.17.1

This is a small test that will check for the ability to parse
both legacy and modern options for rbd.

The way the test is set up is for failure to occur, but without
having to wait to timeout on a non-existent rbd server.  The error
messages in the success path show that the arguments were parsed.

The failure behavior prior to the patch series that has this test, is
qemu-img complaining about mandatory options (e.g. 'pool') not being
provided.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Message-id: f830580e339b974a83ed4870d11adcdc17f49a47.1536704901.git.jcody@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 tests/qemu-iotests/231     | 62 ++++++++++++++++++++++++++++++++++++++
 tests/qemu-iotests/231.out |  9 ++++++
 tests/qemu-iotests/group   |  1 +
 3 files changed, 72 insertions(+)
 create mode 100755 tests/qemu-iotests/231
 create mode 100644 tests/qemu-iotests/231.out

diff --git a/tests/qemu-iotests/231 b/tests/qemu-iotests/231
new file mode 100755
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/tests/qemu-iotests/231
@@ -XXX,XX +XXX,XX @@
+#!/bin/bash
+#
+# Test legacy and modern option parsing for rbd/ceph.  This will not
+# actually connect to a ceph server, but rather looks for the appropriate
+# error message that indicates we parsed the options correctly.
+#
+# Copyright (C) 2018 Red Hat, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+# creator
+owner=jcody@redhat.com
+
+seq=`basename $0`
+echo "QA output created by $seq"
+
+here=`pwd`
+status=1	# failure is the default!
+
+_cleanup()
+{
+    rm "${BOGUS_CONF}"
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+# get standard environment, filters and checks
+. ./common.rc
+. ./common.filter
+
+_supported_fmt generic
+_supported_proto rbd
+_supported_os Linux
+
+BOGUS_CONF=${TEST_DIR}/ceph-$$.conf
+touch "${BOGUS_CONF}"
+
+_filter_conf()
+{
+    sed -e "s#$BOGUS_CONF#BOGUS_CONF#g"
+}
+
+# We expect this to fail, with no monitor ip provided and a null conf file.  Just want it
+# to fail in the right way.
+$QEMU_IMG info "json:{'file.driver':'rbd','file.filename':'rbd:rbd/bogus:conf=${BOGUS_CONF}'}" 2>&1 | _filter_conf
+$QEMU_IMG info "json:{'file.driver':'rbd','file.pool':'rbd','file.image':'bogus','file.conf':'${BOGUS_CONF}'}" 2>&1 | _filter_conf
+
+# success, all done
+echo "*** done"
+rm -f $seq.full
+status=0
diff --git a/tests/qemu-iotests/231.out b/tests/qemu-iotests/231.out
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/tests/qemu-iotests/231.out
@@ -XXX,XX +XXX,XX @@
+QA output created by 231
+qemu-img: RBD options encoded in the filename as keyvalue pairs is deprecated.  Future versions may cease to parse these options in the future.
+unable to get monitor info from DNS SRV with service name: ceph-mon
+no monitors specified to connect to.
+qemu-img: Could not open 'json:{'file.driver':'rbd','file.filename':'rbd:rbd/bogus:conf=BOGUS_CONF'}': error connecting: No such file or directory
+unable to get monitor info from DNS SRV with service name: ceph-mon
+no monitors specified to connect to.
+qemu-img: Could not open 'json:{'file.driver':'rbd','file.pool':'rbd','file.image':'bogus','file.conf':'BOGUS_CONF'}': error connecting: No such file or directory
+*** done
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index XXXXXXX..XXXXXXX 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -XXX,XX +XXX,XX @@
 226 auto quick
 227 auto quick
 229 auto quick
+231 auto quick
-- 
2.17.1

Signed-off-by: Jeff Cody <jcody@redhat.com>
Message-id: 647f5b5ab7efd8bf567a504c832b1d2d6f719b23.1536704901.git.jcody@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 qemu-deprecated.texi | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/qemu-deprecated.texi b/qemu-deprecated.texi
index XXXXXXX..XXXXXXX 100644
--- a/qemu-deprecated.texi
+++ b/qemu-deprecated.texi
@@ -XXX,XX +XXX,XX @@ used instead.
 In order to prevent QEMU from automatically opening an image's backing
 chain, use ``"backing": null'' instead.
 
+@subsubsection rbd keyvalue pair encoded filenames: "" (since 3.1.0)
+
+Options for ``rbd'' should be specified according to its runtime options,
+like other block drivers.  Legacy parsing of keyvalue pair encoded
+filenames is useful to open images with the old format for backing files;
+These image files should be updated to use the current format.
+
+Example of legacy encoding:
+
+@code{json:@{"file.driver":"rbd", "file.filename":"rbd:rbd/name"@}}
+
+The above, converted to the current supported format:
+
+@code{json:@{"file.driver":"rbd", "file.pool":"rbd", "file.image":"name"@}}
+
 @subsection vio-spapr-device device options
 
 @subsubsection "irq": "" (since 3.0.0)
-- 
2.17.1

The main loop thread can consume 100% CPU when using --device
virtio-blk-pci,iothread=<iothread>. ppoll() constantly returns but
reading virtqueue host notifiers fails with EAGAIN. The file descriptors
are stale and remain registered with the AioContext because of bugs in
the virtio-blk dataplane start/stop code.

The problem is that the dataplane start/stop code involves drain
operations, which call virtio_blk_drained_begin() and
virtio_blk_drained_end() at points where the host notifier is not
operational:
- In virtio_blk_data_plane_start(), blk_set_aio_context() drains after
  vblk->dataplane_started has been set to true but the host notifier has
  not been attached yet.
- In virtio_blk_data_plane_stop(), blk_drain() and blk_set_aio_context()
  drain after the host notifier has already been detached but with
  vblk->dataplane_started still set to true.

I would like to simplify ->ioeventfd_start/stop() to avoid interactions
with drain entirely, but couldn't find a way to do that. Instead, this
patch accepts the fragile nature of the code and reorders it so that
vblk->dataplane_started is false during drain operations. This way the
virtio_blk_drained_begin() and virtio_blk_drained_end() calls don't
touch the host notifier. The result is that
virtio_blk_data_plane_start() and virtio_blk_data_plane_stop() have
complete control over the host notifier and stale file descriptors are
no longer left in the AioContext.

This patch fixes the 100% CPU consumption in the main loop thread and
correctly moves host notifier processing to the IOThread.

Fixes: 1665d9326fd2 ("virtio-blk: implement BlockDevOps->drained_begin()")
Reported-by: Lukáš Doktor <ldoktor@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Lukas Doktor <ldoktor@redhat.com>
Message-id: 20230704151527.193586-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 hw/block/dataplane/virtio-blk.c | 67 +++++++++++++++++++--------------
 1 file changed, 38 insertions(+), 29 deletions(-)

diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
index XXXXXXX..XXXXXXX 100644
--- a/hw/block/dataplane/virtio-blk.c
+++ b/hw/block/dataplane/virtio-blk.c
@@ -XXX,XX +XXX,XX @@ int virtio_blk_data_plane_start(VirtIODevice *vdev)
 
     memory_region_transaction_commit();
 
-    /*
-     * These fields are visible to the IOThread so we rely on implicit barriers
-     * in aio_context_acquire() on the write side and aio_notify_accept() on
-     * the read side.
-     */
-    s->starting = false;
-    vblk->dataplane_started = true;
     trace_virtio_blk_data_plane_start(s);
 
     old_context = blk_get_aio_context(s->conf->conf.blk);
@@ -XXX,XX +XXX,XX @@ int virtio_blk_data_plane_start(VirtIODevice *vdev)
         event_notifier_set(virtio_queue_get_host_notifier(vq));
     }
 
+    /*
+     * These fields must be visible to the IOThread when it processes the
+     * virtqueue, otherwise it will think dataplane has not started yet.
+     *
+     * Make sure ->dataplane_started is false when blk_set_aio_context() is
+     * called above so that draining does not cause the host notifier to be
+     * detached/attached prematurely.
+     */
+    s->starting = false;
+    vblk->dataplane_started = true;
+    smp_wmb(); /* paired with aio_notify_accept() on the read side */
+
     /* Get this show started by hooking up our callbacks */
     if (!blk_in_drain(s->conf->conf.blk)) {
         aio_context_acquire(s->ctx);
@@ -XXX,XX +XXX,XX @@ int virtio_blk_data_plane_start(VirtIODevice *vdev)
   fail_guest_notifiers:
     vblk->dataplane_disabled = true;
     s->starting = false;
-    vblk->dataplane_started = true;
     return -ENOSYS;
 }
 
@@ -XXX,XX +XXX,XX @@ void virtio_blk_data_plane_stop(VirtIODevice *vdev)
         aio_wait_bh_oneshot(s->ctx, virtio_blk_data_plane_stop_bh, s);
     }
 
+    /*
+     * Batch all the host notifiers in a single transaction to avoid
+     * quadratic time complexity in address_space_update_ioeventfds().
+     */
+    memory_region_transaction_begin();
+
+    for (i = 0; i < nvqs; i++) {
+        virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), i, false);
+    }
+
+    /*
+     * The transaction expects the ioeventfds to be open when it
+     * commits. Do it now, before the cleanup loop.
+     */
+    memory_region_transaction_commit();
+
+    for (i = 0; i < nvqs; i++) {
+        virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), i);
+    }
+
+    /*
+     * Set ->dataplane_started to false before draining so that host notifiers
+     * are not detached/attached anymore.
+     */
+    vblk->dataplane_started = false;
+
     aio_context_acquire(s->ctx);
 
     /* Wait for virtio_blk_dma_restart_bh() and in flight I/O to complete */
@@ -XXX,XX +XXX,XX @@ void virtio_blk_data_plane_stop(VirtIODevice *vdev)
 
     aio_context_release(s->ctx);
 
-    /*
-     * Batch all the host notifiers in a single transaction to avoid
-     * quadratic time complexity in address_space_update_ioeventfds().
-     */
-    memory_region_transaction_begin();
-
-    for (i = 0; i < nvqs; i++) {
-        virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), i, false);
-    }
-
-    /*
-     * The transaction expects the ioeventfds to be open when it
-     * commits. Do it now, before the cleanup loop.
-     */
-    memory_region_transaction_commit();
-
-    for (i = 0; i < nvqs; i++) {
-        virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), i);
-    }
-
     qemu_bh_cancel(s->bh);
     notify_guest_bh(s); /* final chance to notify guest */
 
     /* Clean up guest notifier (irq) */
     k->set_guest_notifiers(qbus->parent, nvqs, false);
 
-    vblk->dataplane_started = false;
     s->stopping = false;
 }
-- 
2.40.1