block: Allow inactivating already inactive nodes

What we wanted to catch with the assertion is cases where the recursion
finds that a child was inactive before its parent. This should never
happen. But if the user tries to inactivate an image that is already
inactive, that's harmless and we don't want to fail the assertion.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20250204211407.381505-3-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

diff --git a/block.c b/block.c
index 9aad958269f3e28c88340e7a4b5758dafdd5d02a..9458c5e01318c2263bcea0b339d729f2afbfb0a6 100644 (file)
--- a/block.c
+++ b/block.c
@@ -6959,7 +6959,8 @@ bdrv_has_bds_parent(BlockDriverState *bs, bool only_active)
     return false;
 }
 
-static int GRAPH_RDLOCK bdrv_inactivate_recurse(BlockDriverState *bs)
+static int GRAPH_RDLOCK
+bdrv_inactivate_recurse(BlockDriverState *bs, bool top_level)
 {
     BdrvChild *child, *parent;
     int ret;
@@ -6977,7 +6978,14 @@ static int GRAPH_RDLOCK bdrv_inactivate_recurse(BlockDriverState *bs)
         return 0;
     }
 
-    assert(!(bs->open_flags & BDRV_O_INACTIVE));
+    /*
+     * Inactivating an already inactive node on user request is harmless, but if
+     * a child is already inactive before its parent, that's bad.
+     */
+    if (bs->open_flags & BDRV_O_INACTIVE) {
+        assert(top_level);
+        return 0;
+    }
 
     /* Inactivate this node */
     if (bs->drv->bdrv_inactivate) {
@@ -7014,7 +7022,7 @@ static int GRAPH_RDLOCK bdrv_inactivate_recurse(BlockDriverState *bs)
 
     /* Recursively inactivate children */
     QLIST_FOREACH(child, &bs->children, next) {
-        ret = bdrv_inactivate_recurse(child->bs);
+        ret = bdrv_inactivate_recurse(child->bs, false);
         if (ret < 0) {
             return ret;
         }
@@ -7039,7 +7047,7 @@ int bdrv_inactivate_all(void)
         if (bdrv_has_bds_parent(bs, false)) {
             continue;
         }
-        ret = bdrv_inactivate_recurse(bs);
+        ret = bdrv_inactivate_recurse(bs, true);
         if (ret < 0) {
             bdrv_next_cleanup(&it);
             break;