migration: not necessary to check ops again

[mirror_qemu.git] / block.c

diff --git a/block.c b/block.c
index 0a93ee9ac84c590ab8cd399a7d60c19d11c8a69b..6999aad4460b1ae1651217374f9575d12d22eb32 100644 (file)
--- a/block.c
+++ b/block.c
@@ -950,8 +950,9 @@ static void bdrv_temp_snapshot_options(int *child_flags, QDict *child_options,
     qdict_set_default_str(child_options, BDRV_OPT_CACHE_DIRECT, "off");
     qdict_set_default_str(child_options, BDRV_OPT_CACHE_NO_FLUSH, "on");
 
-    /* Copy the read-only option from the parent */
+    /* Copy the read-only and discard options from the parent */
     qdict_copy_default(child_options, parent_options, BDRV_OPT_READ_ONLY);
+    qdict_copy_default(child_options, parent_options, BDRV_OPT_DISCARD);
 
     /* aio=native doesn't work for cache.direct=off, so disable it for the
      * temporary snapshot */
@@ -1742,11 +1743,10 @@ static void bdrv_child_perm(BlockDriverState *bs, BlockDriverState *child_bs,
                             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;
@@ -4082,14 +4082,14 @@ static void bdrv_delete(BlockDriverState *bs)
     assert(bdrv_op_blocker_is_empty(bs));
     assert(!bs->refcnt);
 
-    bdrv_close(bs);
-
     /* remove from list, if necessary */
     if (bs->node_name[0] != '\0') {
         QTAILQ_REMOVE(&graph_bdrv_states, bs, node_list);
     }
     QTAILQ_REMOVE(&all_bdrv_states, bs, bs_list);
 
+    bdrv_close(bs);
+
     g_free(bs);
 }
 
@@ -4121,7 +4121,7 @@ typedef struct CheckCo {
     int ret;
 } CheckCo;
 
-static void bdrv_check_co_entry(void *opaque)
+static void coroutine_fn bdrv_check_co_entry(void *opaque)
 {
     CheckCo *cco = opaque;
     cco->ret = bdrv_co_check(cco->bs, cco->res, cco->fix);
@@ -4218,14 +4218,15 @@ BlockDriverState *bdrv_find_base(BlockDriverState *bs)
 /*
  * Return true if at least one of the backing links between @bs and
  * @base is frozen. @errp is set if that's the case.
+ * @base must be reachable from @bs, or NULL.
  */
 bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base,
                                   Error **errp)
 {
     BlockDriverState *i;
 
-    for (i = bs; i != base && i->backing; i = backing_bs(i)) {
-        if (i->backing->frozen) {
+    for (i = bs; i != base; i = backing_bs(i)) {
+        if (i->backing && i->backing->frozen) {
             error_setg(errp, "Cannot change '%s' link from '%s' to '%s'",
                        i->backing->name, i->node_name,
                        backing_bs(i)->node_name);
@@ -4240,6 +4241,7 @@ bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base,
  * Freeze all backing links between @bs and @base.
  * If any of the links is already frozen the operation is aborted and
  * none of the links are modified.
+ * @base must be reachable from @bs, or NULL.
  * Returns 0 on success. On failure returns < 0 and sets @errp.
  */
 int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base,
@@ -4251,8 +4253,10 @@ int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base,
         return -EPERM;
     }
 
-    for (i = bs; i != base && i->backing; i = backing_bs(i)) {
-        i->backing->frozen = true;
+    for (i = bs; i != base; i = backing_bs(i)) {
+        if (i->backing) {
+            i->backing->frozen = true;
+        }
     }
 
     return 0;
@@ -4261,14 +4265,17 @@ int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base,
 /*
  * Unfreeze all backing links between @bs and @base. The caller must
  * ensure that all links are frozen before using this function.
+ * @base must be reachable from @bs, or NULL.
  */
 void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base)
 {
     BlockDriverState *i;
 
-    for (i = bs; i != base && i->backing; i = backing_bs(i)) {
-        assert(i->backing->frozen);
-        i->backing->frozen = false;
+    for (i = bs; i != base; i = backing_bs(i)) {
+        if (i->backing) {
+            assert(i->backing->frozen);
+            i->backing->frozen = false;
+        }
     }
 }
 
@@ -5664,10 +5671,6 @@ void bdrv_detach_aio_context(BlockDriverState *bs)
     BdrvAioNotifier *baf, *baf_tmp;
     BdrvChild *child;
 
-    if (!bs->drv) {
-        return;
-    }
-
     assert(!bs->walking_aio_notifiers);
     bs->walking_aio_notifiers = true;
     QLIST_FOREACH_SAFE(baf, &bs->aio_notifiers, list, baf_tmp) {
@@ -5682,7 +5685,7 @@ void bdrv_detach_aio_context(BlockDriverState *bs)
      */
     bs->walking_aio_notifiers = false;
 
-    if (bs->drv->bdrv_detach_aio_context) {
+    if (bs->drv && bs->drv->bdrv_detach_aio_context) {
         bs->drv->bdrv_detach_aio_context(bs);
     }
     QLIST_FOREACH(child, &bs->children, next) {
@@ -5701,10 +5704,6 @@ void bdrv_attach_aio_context(BlockDriverState *bs,
     BdrvAioNotifier *ban, *ban_tmp;
     BdrvChild *child;
 
-    if (!bs->drv) {
-        return;
-    }
-
     if (bs->quiesce_counter) {
         aio_disable_external(new_context);
     }
@@ -5714,7 +5713,7 @@ void bdrv_attach_aio_context(BlockDriverState *bs,
     QLIST_FOREACH(child, &bs->children, next) {
         bdrv_attach_aio_context(child->bs, new_context);
     }
-    if (bs->drv->bdrv_attach_aio_context) {
+    if (bs->drv && bs->drv->bdrv_attach_aio_context) {
         bs->drv->bdrv_attach_aio_context(bs, new_context);
     }