dm thin metadata: check __commit_transaction()'s return

Fix __reserve_metadata_snap() to return early if __commit_transaction()
fails.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>

diff --git a/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c
index ed3cace..7381e47 100644 (file)
--- a/drivers/md/dm-thin-metadata.c
+++ b/drivers/md/dm-thin-metadata.c
@@ -1225,7 +1225,12 @@ static int __reserve_metadata_snap(struct dm_pool_metadata *pmd)
         * We commit to ensure the btree roots which we increment in a
         * moment are up to date.
         */
-       __commit_transaction(pmd);
+       r = __commit_transaction(pmd);
+       if (r < 0) {
+               DMWARN("%s: __commit_transaction() failed, error = %d",
+                      __func__, r);
+               return r;
+       }
 
        /*
         * Copy the superblock.