[PATCH 7/8] block: improve bdrv_replace_node_noperm()
Add optional block edge name filter and new mode: "exactly one", which
we are going to use soon.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov(a)virtuozzo.com>
---
block.c | 27 ++++++++++++++++++++++++---
1 file changed, 24 insertions(+), 3 deletions(-)
diff --git a/block.c b/block.c
index 449f933661..ae8c8c4032 100644
--- a/block.c
+++ b/block.c
@@ -4894,13 +4894,22 @@ static void bdrv_remove_filter_or_cow_child(BlockDriverState *bs,
static int bdrv_replace_node_noperm(BlockDriverState *from,
BlockDriverState *to,
- bool auto_skip, Transaction *tran,
+ bool auto_skip,
+ const char *edge_name,
+ bool exactly_one,
+ Transaction *tran,
Error **errp)
{
BdrvChild *c, *next;
+ bool found = false;
+
+ assert(!(auto_skip && exactly_one));
QLIST_FOREACH_SAFE(c, &from->parents, next_parent, next) {
assert(c->bs == from);
+ if (edge_name && strcmp(edge_name, c->name)) {
+ continue;
+ }
if (!should_update_child(c, to)) {
if (auto_skip) {
continue;
@@ -4914,9 +4923,19 @@ static int bdrv_replace_node_noperm(BlockDriverState *from,
c->name, from->node_name);
return -EPERM;
}
+ if (exactly_one && found) {
+ error_setg(errp, "More than one matching parents found");
+ return -EINVAL;
+ }
+ found = true;
bdrv_replace_child_tran(c, to, tran);
}
+ if (exactly_one && !found) {
+ error_setg(errp, "No one matching parents found");
+ return -EINVAL;
+ }
+
return 0;
}
@@ -4966,7 +4985,8 @@ static int bdrv_replace_node_common(BlockDriverState *from,
* permissions based on new graph. If we fail, we'll roll-back the
* replacement.
*/
- ret = bdrv_replace_node_noperm(from, to, auto_skip, tran, errp);
+ ret = bdrv_replace_node_noperm(from, to, auto_skip, NULL, false,
+ tran, errp);
if (ret < 0) {
goto out;
}
@@ -5035,7 +5055,8 @@ int bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top,
goto out;
}
- ret = bdrv_replace_node_noperm(bs_top, bs_new, true, tran, errp);
+ ret = bdrv_replace_node_noperm(bs_top, bs_new, true, NULL, false,
+ tran, errp);
if (ret < 0) {
goto out;
}
--
2.29.2