Commit 4ef3982a authored by Stefan Hajnoczi's avatar Stefan Hajnoczi Committed by Kevin Wolf
Browse files

blockdev: acquire AioContext in blockdev-snapshot-delete-internal-sync 



Add dataplane support to the blockdev-snapshot-delete-internal-sync QMP
command.  By acquiring the AioContext we avoid race conditions with the
dataplane thread which may also be accessing the BlockDriverState.

Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: default avatarMax Reitz <mreitz@redhat.com>
Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent 2389eeae

blockdev.c

+13 −3
Original line number Diff line number Diff line
@@ -1105,6 +1105,7 @@ SnapshotInfo *qmp_blockdev_snapshot_delete_internal_sync(const char *device, 
                                                         Error **errp)

{

    BlockDriverState *bs = bdrv_find(device);

    AioContext *aio_context;

    QEMUSnapshotInfo sn;

    Error *local_err = NULL;

    SnapshotInfo *info = NULL;
@@ -1128,25 +1129,30 @@ SnapshotInfo *qmp_blockdev_snapshot_delete_internal_sync(const char *device, 
        return NULL;

    }



    aio_context = bdrv_get_aio_context(bs);

    aio_context_acquire(aio_context);



    ret = bdrv_snapshot_find_by_id_and_name(bs, id, name, &sn, &local_err);

    if (local_err) {

        error_propagate(errp, local_err);

        return NULL;

        goto out_aio_context;

    }

    if (!ret) {

        error_setg(errp,

                   "Snapshot with id '%s' and name '%s' does not exist on "

                   "device '%s'",

                   STR_OR_NULL(id), STR_OR_NULL(name), device);

        return NULL;

        goto out_aio_context;

    }



    bdrv_snapshot_delete(bs, id, name, &local_err);

    if (local_err) {

        error_propagate(errp, local_err);

        return NULL;

        goto out_aio_context;

    }



    aio_context_release(aio_context);



    info = g_new0(SnapshotInfo, 1);

    info->id = g_strdup(sn.id_str);

    info->name = g_strdup(sn.name);
@@ -1157,6 +1163,10 @@ SnapshotInfo *qmp_blockdev_snapshot_delete_internal_sync(const char *device, 
    info->vm_clock_sec = sn.vm_clock_nsec / 1000000000;



    return info;



out_aio_context:

    aio_context_release(aio_context);

    return NULL;

}



/* New and old BlockDriverState structs for group snapshots */

hw/block/dataplane/virtio-blk.c

+2 −0
Original line number Diff line number Diff line
@@ -198,6 +198,8 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *conf, 
    blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_DRIVE_DEL, s->blocker);

    blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_BACKUP_SOURCE, s->blocker);

    blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_COMMIT, s->blocker);

    blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE,

                   s->blocker);

    blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_MIRROR, s->blocker);

    blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_STREAM, s->blocker);

    blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_REPLACE, s->blocker);