commit 0b3ca76e52f025caf234b77d471465e983a711d0
author Alberto Garcia <berto@igalia.com> Thu Apr 04 14:29:53 2019 +0300
committer Max Reitz <mreitz@redhat.com> Tue May 07 17:14:21 2019 +0200
tree 8fb17e78f1ee5275ff0ac74c43e05ff3e4d97626
parent 21205c7c3bd0910d7b71274ddbede9c7001e1cb4

block: Assert that drv->bdrv_child_perm is set in bdrv_child_perm()

There is no need to check for this because all block drivers that have
children implement bdrv_child_perm and all callers already ensure that
bs->drv is set.

Furthermore, if this check would fail then the callers would end up
with uninitialized values for nperm and nshared.

This patch replaces the check with an assertion.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: 20190404112953.4058-1-berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

block.c

diff --git a/block.c b/block.c
index 9ae5c0e..7dc8fe2 100644
--- a/block.c
+++ b/block.c
@@ -1743,11 +1743,10 @@
                             uint64_t parent_perm, uint64_t parent_shared,
                             uint64_t *nperm, uint64_t *nshared)
 {
-    if (bs->drv && bs->drv->bdrv_child_perm) {
-        bs->drv->bdrv_child_perm(bs, c, role, reopen_queue,
-                                 parent_perm, parent_shared,
-                                 nperm, nshared);
-    }
+    assert(bs->drv && bs->drv->bdrv_child_perm);
+    bs->drv->bdrv_child_perm(bs, c, role, reopen_queue,
+                             parent_perm, parent_shared,
+                             nperm, nshared);
     /* TODO Take force_share from reopen_queue */
     if (child_bs && child_bs->force_share) {
         *nshared = BLK_PERM_ALL;