From a9ef5c84766a00677204474b0f8d8e845b9d4d3f Mon Sep 17 00:00:00 2001

From: Stefan Hajnoczi <stefanha@redhat.com>

Date: Fri, 22 Dec 2017 11:08:53 +0100

Subject: [PATCH 35/42] block: don't keep AioContext acquired after

 internal_snapshot_prepare()

RH-Author: Stefan Hajnoczi <stefanha@redhat.com>

Message-id: <20171222110900.24813-14-stefanha@redhat.com>

Patchwork-id: 78499

O-Subject: [RHV7.5 qemu-kvm-rhev PATCH 13/20] block: don't keep AioContext acquired after internal_snapshot_prepare()

Bugzilla: 1519721

RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>

RH-Acked-by: Jeffrey Cody <jcody@redhat.com>

RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Reviewed-by: Kevin Wolf <kwolf@redhat.com>

Reviewed-by: Eric Blake <eblake@redhat.com>

Message-id: 20171206144550.22295-6-stefanha@redhat.com

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

(cherry picked from commit a36e458cdda0196911c1cbe7cfe6f9530f2280e3)

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 blockdev.c | 47 +++++++++++++++++++++++++++++++----------------

 1 file changed, 31 insertions(+), 16 deletions(-)

diff --git a/blockdev.c b/blockdev.c

index 6efae53..f118444 100644

--- a/blockdev.c

+++ b/blockdev.c

@@ -1497,7 +1497,6 @@ struct BlkActionState {

 typedef struct InternalSnapshotState {

     BlkActionState common;

     BlockDriverState *bs;

-    AioContext *aio_context;

     QEMUSnapshotInfo sn;

     bool created;

 } InternalSnapshotState;

@@ -1528,6 +1527,7 @@ static void internal_snapshot_prepare(BlkActionState *common,

     qemu_timeval tv;

     BlockdevSnapshotInternal *internal;

     InternalSnapshotState *state;

+    AioContext *aio_context;

     int ret1;

     g_assert(common->action->type ==

@@ -1549,32 +1549,33 @@ static void internal_snapshot_prepare(BlkActionState *common,

         return;

     }

-    /* AioContext is released in .clean() */

-    state->aio_context = bdrv_get_aio_context(bs);

-    aio_context_acquire(state->aio_context);

+    aio_context = bdrv_get_aio_context(bs);

+    aio_context_acquire(aio_context);

     state->bs = bs;

+

+    /* Paired with .clean() */

     bdrv_drained_begin(bs);

     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, errp)) {

-        return;

+        goto out;

     }

     if (bdrv_is_read_only(bs)) {

         error_setg(errp, "Device '%s' is read only", device);

-        return;

+        goto out;

     }

     if (!bdrv_can_snapshot(bs)) {

         error_setg(errp, "Block format '%s' used by device '%s' "

                    "does not support internal snapshots",

                    bs->drv->format_name, device);

-        return;

+        goto out;

     }

     if (!strlen(name)) {

         error_setg(errp, "Name is empty");

-        return;

+        goto out;

     }

     /* check whether a snapshot with name exist */

@@ -1582,12 +1583,12 @@ static void internal_snapshot_prepare(BlkActionState *common,

                                             &local_err);

     if (local_err) {

         error_propagate(errp, local_err);

-        return;

+        goto out;

     } else if (ret) {

         error_setg(errp,

                    "Snapshot with name '%s' already exists on device '%s'",

                    name, device);

-        return;

+        goto out;

     }

     /* 3. take the snapshot */

@@ -1603,11 +1604,14 @@ static void internal_snapshot_prepare(BlkActionState *common,

         error_setg_errno(errp, -ret1,

                          "Failed to create snapshot '%s' on device '%s'",

                          name, device);

-        return;

+        goto out;

     }

     /* 4. succeed, mark a snapshot is created */

     state->created = true;

+

+out:

+    aio_context_release(aio_context);

 }

 static void internal_snapshot_abort(BlkActionState *common)

@@ -1616,12 +1620,16 @@ static void internal_snapshot_abort(BlkActionState *common)

                              DO_UPCAST(InternalSnapshotState, common, common);

     BlockDriverState *bs = state->bs;

     QEMUSnapshotInfo *sn = &state->sn;

+    AioContext *aio_context;

     Error *local_error = NULL;

     if (!state->created) {

         return;

     }

+    aio_context = bdrv_get_aio_context(state->bs);

+    aio_context_acquire(aio_context);

+

     if (bdrv_snapshot_delete(bs, sn->id_str, sn->name, &local_error) < 0) {

         error_reportf_err(local_error,

                           "Failed to delete snapshot with id '%s' and "

@@ -1629,19 +1637,26 @@ static void internal_snapshot_abort(BlkActionState *common)

                           sn->id_str, sn->name,

                           bdrv_get_device_name(bs));

     }

+

+    aio_context_release(aio_context);

 }

 static void internal_snapshot_clean(BlkActionState *common)

 {

     InternalSnapshotState *state = DO_UPCAST(InternalSnapshotState,

                                              common, common);

+    AioContext *aio_context;

-    if (state->aio_context) {

-        if (state->bs) {

-            bdrv_drained_end(state->bs);

-        }

-        aio_context_release(state->aio_context);

+    if (!state->bs) {

+        return;

     }

+

+    aio_context = bdrv_get_aio_context(state->bs);

+    aio_context_acquire(aio_context);

+

+    bdrv_drained_end(state->bs);

+

+    aio_context_release(aio_context);

 }

 /* external snapshot private data */

-- 

1.8.3.1