qcow2: set L2 cache dependency in qcow2_alloc_bytes()
Compressed writes use qcow2_alloc_bytes() to allocate space with byte
granularity. The affected clusters' refcounts will be incremented but
we do not need to flush yet.
Set a L2 cache dependency on the refcount block cache, so that the
refcounts get written out before the L2 updates.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index e8b5d0a..4d9df5f 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -669,7 +669,11 @@
}
}
- bdrv_flush(bs->file);
+ /* The cluster refcount was incremented, either by qcow2_alloc_clusters()
+ * or explicitly by update_cluster_refcount(). Refcount blocks must be
+ * flushed before the caller's L2 table updates.
+ */
+ qcow2_cache_set_dependency(bs, s->l2_table_cache, s->refcount_block_cache);
return offset;
}
