bdrv_do_drained_begin() restricts the call of parent callbacks and
aio_disable_external() to the outermost drain section, but the block
driver callbacks are always called. bdrv_do_drained_end() must match
this behaviour, otherwise nodes stay drained even if begin/end calls
were balanced.
Signed-off-by: Kevin Wolf <kw...@redhat.com>
---
block/io.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/block/io.c b/block/io.c
index 74d2e5278e..6038a16c58 100644
--- a/block/io.c
+++ b/block/io.c
@@ -273,19 +273,21 @@ void bdrv_drained_begin(BlockDriverState *bs)
void bdrv_drained_end(BlockDriverState *bs)
{
+ int old_quiesce_counter;
+
if (qemu_in_coroutine()) {
bdrv_co_yield_to_drain(bs, false);
return;
}
assert(bs->quiesce_counter > 0);
- if (atomic_fetch_dec(&bs->quiesce_counter) > 1) {
- return;
- }
+ old_quiesce_counter = atomic_fetch_dec(&bs->quiesce_counter);
/* Re-enable things in child-to-parent order */
bdrv_drain_invoke(bs, false, false);
- bdrv_parent_drained_end(bs);
- aio_enable_external(bdrv_get_aio_context(bs));
+ if (old_quiesce_counter == 1) {
+ bdrv_parent_drained_end(bs);
+ aio_enable_external(bdrv_get_aio_context(bs));
+ }
}
/*
--
2.13.6
