block: wrlock in bdrv_replace_child_noperm

Protect the main function where graph is modified.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-12-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Emanuele Giuseppe Esposito 2022-12-07 14:18:31 +01:00 committed by Kevin Wolf
parent e135505588
commit 2931250780

View File

@ -2836,8 +2836,6 @@ uint64_t bdrv_qapi_perm_to_blk_perm(BlockPermission qapi_perm)
*
* If @new_bs is non-NULL, the parent of @child must already be drained through
* @child.
*
* This function does not poll.
*/
static void bdrv_replace_child_noperm(BdrvChild *child,
BlockDriverState *new_bs)
@ -2875,23 +2873,24 @@ static void bdrv_replace_child_noperm(BdrvChild *child,
assert(bdrv_get_aio_context(old_bs) == bdrv_get_aio_context(new_bs));
}
/* TODO Pull this up into the callers to avoid polling here */
bdrv_graph_wrlock();
if (old_bs) {
if (child->klass->detach) {
child->klass->detach(child);
}
assert_bdrv_graph_writable(old_bs);
QLIST_REMOVE(child, next_parent);
}
child->bs = new_bs;
if (new_bs) {
assert_bdrv_graph_writable(new_bs);
QLIST_INSERT_HEAD(&new_bs->parents, child, next_parent);
if (child->klass->attach) {
child->klass->attach(child);
}
}
bdrv_graph_wrunlock();
/*
* If the parent was drained through this BdrvChild previously, but new_bs