block: check return value of bdrv_open_child and drop error propagation

This patch is generated by cocci script:

@@
symbol bdrv_open_child, errp, local_err;
expression file;
@@

  file = bdrv_open_child(...,
-                        &local_err
+                        errp
                        );
- if (local_err)
+ if (!file)
  {
      ...
-     error_propagate(errp, local_err);
      ...
  }

with command

spatch --sp-file x.cocci --macro-file scripts/cocci-macro-file.h \
--in-place --no-show-diff --max-width 80 --use-gitgrep block

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-Id: <20210202124956.63146-4-vsementsov@virtuozzo.com>
[eblake: fix qcow2_do_open() to use ERRP_GUARD, necessary as the only
caller to pass allow_none=true]
Signed-off-by: Eric Blake <eblake@redhat.com>

1 files changed, 2 insertions, 4 deletions

diff --git a/block/blkdebug.c b/block/blkdebug.c
index 7eaa8a28bf..2c0b9b0ee8 100644
--- a/block/blkdebug.c
+++ b/block/blkdebug.c
@@ -464,7 +464,6 @@ static int blkdebug_open(BlockDriverState *bs, QDict *options, int flags,
 {
     BDRVBlkdebugState *s = bs->opaque;
     QemuOpts *opts;
-    Error *local_err = NULL;
     int ret;
     uint64_t align;
 
@@ -494,10 +493,9 @@ static int blkdebug_open(BlockDriverState *bs, QDict *options, int flags,
     bs->file = bdrv_open_child(qemu_opt_get(opts, "x-image"), options, "image",
                                bs, &child_of_bds,
                                BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY,
-                               false, &local_err);
-    if (local_err) {
+                               false, errp);
+    if (!bs->file) {
         ret = -EINVAL;
-        error_propagate(errp, local_err);
         goto out;
     }