diff mbox

[RFC,7/7] blockdev: Add "device IO" op blocker during snapshot transaction

Message ID 1430911419-8256-8-git-send-email-famz@redhat.com
State New
Headers show

Commit Message

Fam Zheng May 6, 2015, 11:23 a.m. UTC 
Signed-off-by: Fam Zheng <famz@redhat.com>
---
 blockdev.c | 7 +++++++
 1 file changed, 7 insertions(+)
diff mbox

Patch

diff --git a/blockdev.c b/blockdev.c
index 5eaf77e..859fa2e 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1398,6 +1398,7 @@  typedef struct ExternalSnapshotState {
     BlockDriverState *old_bs;
     BlockDriverState *new_bs;
     AioContext *aio_context;
+    Error *blocker;
 } ExternalSnapshotState;
 
 static void external_snapshot_prepare(BlkTransactionState *common,
@@ -1519,6 +1520,9 @@  static void external_snapshot_prepare(BlkTransactionState *common,
     if (ret != 0) {
         error_propagate(errp, local_err);
     }
+
+    error_setg(&state->blocker, "snapshot in progress");
+    bdrv_op_block(state->old_bs, BLOCK_OP_TYPE_DEVICE_IO, state->blocker);
 }
 
 static void external_snapshot_commit(BlkTransactionState *common)
@@ -1536,6 +1540,9 @@  static void external_snapshot_commit(BlkTransactionState *common)
     bdrv_reopen(state->new_bs, state->new_bs->open_flags & ~BDRV_O_RDWR,
                 NULL);
 
+    bdrv_op_unblock(state->old_bs, BLOCK_OP_TYPE_DEVICE_IO, state->blocker);
+    error_free(state->blocker);
+
     aio_context_release(state->aio_context);
 }