Merge remote-tracking branch 'stefanha/block' into staging

# By Paolo Bonzini (21) and others
# Via Stefan Hajnoczi
* stefanha/block: (42 commits)
  qemu-iotests: Fixed test case 026
  qemu-iotests: Whitespace cleanup
  dataplane: Fix startup race.
  block: look for zero blocks in bs->file
  block: add default get_block_status implementation for protocols
  raw-posix: report unwritten extents as zero
  raw-posix: return get_block_status data and flags
  docs, qapi: document qemu-img map
  qemu-img: add a "map" subcommand
  block: return BDRV_BLOCK_ZERO past end of backing file
  block: use bdrv_has_zero_init to return BDRV_BLOCK_ZERO
  block: return get_block_status data and flags for formats
  block: define get_block_status return value
  block: introduce bdrv_get_block_status API
  block: make bdrv_has_zero_init return false for copy-on-write-images
  qemu-img: always probe the input image for allocated sectors
  block: expect errors from bdrv_co_is_allocated
  block: remove bdrv_is_allocated_above/bdrv_co_is_allocated_above distinction
  block: do not use ->total_sectors in bdrv_co_is_allocated
  block: make bdrv_co_is_allocated static
  ...

Message-id: 1378481953-23099-1-git-send-email-stefanha@redhat.com
Signed-off-by: Anthony Liguori <anthony@codemonkey.ws>

2 files changed, 15 insertions, 7 deletions

diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
index 5a96ccd416..f2d7350a50 100644
--- a/hw/block/dataplane/virtio-blk.c
+++ b/hw/block/dataplane/virtio-blk.c
@@ -42,6 +42,7 @@ typedef struct {
 
 struct VirtIOBlockDataPlane {
     bool started;
+    bool starting;
     bool stopping;
     QEMUBH *start_bh;
     QemuThread thread;
@@ -451,8 +452,15 @@ void virtio_blk_data_plane_start(VirtIOBlockDataPlane *s)
         return;
     }
 
+    if (s->starting) {
+        return;
+    }
+
+    s->starting = true;
+
     vq = virtio_get_queue(s->vdev, 0);
     if (!vring_setup(&s->vring, s->vdev, 0)) {
+        s->starting = false;
         return;
     }
 
@@ -482,6 +490,7 @@ void virtio_blk_data_plane_start(VirtIOBlockDataPlane *s)
     s->io_notifier = *ioq_get_notifier(&s->ioqueue);
     aio_set_event_notifier(s->ctx, &s->io_notifier, handle_io);
 
+    s->starting = false;
     s->started = true;
     trace_virtio_blk_data_plane_start(s);
 
diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c
index 727f4331c0..668cc069ff 100644
--- a/hw/block/xen_disk.c
+++ b/hw/block/xen_disk.c
@@ -813,7 +813,7 @@ static int blk_connect(struct XenDevice *xendev)
                                                            readonly);
             if (bdrv_open(blkdev->bs,
                           blkdev->filename, NULL, qflags, drv) != 0) {
-                bdrv_delete(blkdev->bs);
+                bdrv_unref(blkdev->bs);
                 blkdev->bs = NULL;
             }
         }
@@ -824,6 +824,9 @@ static int blk_connect(struct XenDevice *xendev)
         /* setup via qemu cmdline -> already setup for us */
         xen_be_printf(&blkdev->xendev, 2, "get configured bdrv (cmdline setup)\n");
         blkdev->bs = blkdev->dinfo->bdrv;
+        /* blkdev->bs is not create by us, we get a reference
+         * so we can bdrv_unref() unconditionally */
+        bdrv_ref(blkdev->bs);
     }
     bdrv_attach_dev_nofail(blkdev->bs, blkdev);
     blkdev->file_size = bdrv_getlength(blkdev->bs);
@@ -922,12 +925,8 @@ static void blk_disconnect(struct XenDevice *xendev)
     struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
 
     if (blkdev->bs) {
-        if (!blkdev->dinfo) {
-            /* close/delete only if we created it ourself */
-            bdrv_close(blkdev->bs);
-            bdrv_detach_dev(blkdev->bs, blkdev);
-            bdrv_delete(blkdev->bs);
-        }
+        bdrv_detach_dev(blkdev->bs, blkdev);
+        bdrv_unref(blkdev->bs);
         blkdev->bs = NULL;
     }
     xen_be_unbind_evtchn(&blkdev->xendev);