Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

Block pull request

# gpg: Signature made Wed 28 May 2014 13:31:15 BST using RSA key ID 81AB73C8
# gpg: Can't check signature: public key not found

* remotes/stefanha/tags/block-pull-request: (33 commits)
  block/sheepdog: Don't use qerror_report()
  block/sheepdog: Fix silent sd_open(), sd_create() failures
  block/sheepdog: Propagate errors to open and create methods
  block/sheepdog: Propagate errors through find_vdi_name()
  block/sheepdog: Propagate errors through do_sd_create()
  block/sheepdog: Propagate errors through sd_prealloc()
  block/sheepdog: Propagate errors through get_sheep_fd()
  block/sheepdog: Propagate errors through connect_to_sdog()
  block/vvfat: Propagate errors through init_directories()
  block/vvfat: Propagate errors through enable_write_target()
  block/ssh: Propagate errors to open and create methods
  block/ssh: Propagate errors through connect_to_ssh()
  block/ssh: Propagate errors through authenticate()
  block/ssh: Propagate errors through check_host_key()
  block/ssh: Drop superfluous libssh2_session_last_errno() calls
  block/rbd: Propagate errors to open and create methods
  qemu-nbd: Don't use qerror_report()
  blockdev: Don't use qerror_report() in do_drive_del()
  blockdev: Don't use qerror_report_err() in drive_init()
  docs: Define refcount_bits value
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 12 insertions, 6 deletions

diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
index 70b8a5ab75..e49c2536b1 100644
--- a/hw/block/dataplane/virtio-blk.c
+++ b/hw/block/dataplane/virtio-blk.c
@@ -70,6 +70,9 @@ struct VirtIOBlockDataPlane {
                                              queue */
 
     unsigned int num_reqs;
+
+    /* Operation blocker on BDS */
+    Error *blocker;
 };
 
 /* Raise an interrupt to signal guest, if necessary */
@@ -350,6 +353,7 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
 {
     VirtIOBlockDataPlane *s;
     int fd;
+    Error *local_err = NULL;
 
     *dataplane = NULL;
 
@@ -372,9 +376,10 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
     /* If dataplane is (re-)enabled while the guest is running there could be
      * block jobs that can conflict.
      */
-    if (bdrv_in_use(blk->conf.bs)) {
-        error_setg(errp,
-                   "cannot start dataplane thread while device is in use");
+    if (bdrv_op_is_blocked(blk->conf.bs, BLOCK_OP_TYPE_DATAPLANE, &local_err)) {
+        error_report("cannot start dataplane thread: %s",
+                      error_get_pretty(local_err));
+        error_free(local_err);
         return;
     }
 
@@ -406,8 +411,8 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
     }
     s->ctx = iothread_get_aio_context(s->iothread);
 
-    /* Prevent block operations that conflict with data plane thread */
-    bdrv_set_in_use(blk->conf.bs, 1);
+    error_setg(&s->blocker, "block device is in use by data plane");
+    bdrv_op_block_all(blk->conf.bs, s->blocker);
 
     *dataplane = s;
 }
@@ -420,7 +425,8 @@ void virtio_blk_data_plane_destroy(VirtIOBlockDataPlane *s)
     }
 
     virtio_blk_data_plane_stop(s);
-    bdrv_set_in_use(s->blk->conf.bs, 0);
+    bdrv_op_unblock_all(s->blk->conf.bs, s->blocker);
+    error_free(s->blocker);
     object_unref(OBJECT(s->iothread));
     g_free(s);
 }