[PATCH v3 04/11] block: bdrv_replace_child_bs(): move to external transaction
We'll need this functionality as part of external transaction, so make
the whole function to be transaction action. For this we need to
introduce a transaction action helper: bdrv_drained(), which calls
bdrv_drained_begin() and postpone bdrv_drained_end() to .clean() phase.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov(a)virtuozzo.com>
---
include/block/block.h | 2 +-
block.c | 42 +++++++++++++++++++++++++++---------------
block/block-backend.c | 8 +++++++-
3 files changed, 35 insertions(+), 17 deletions(-)
diff --git a/include/block/block.h b/include/block/block.h
index e1713ee306..1cc1f736c7 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -362,7 +362,7 @@ int bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top,
int bdrv_replace_node(BlockDriverState *from, BlockDriverState *to,
Error **errp);
int bdrv_replace_child_bs(BdrvChild *child, BlockDriverState *new_bs,
- Error **errp);
+ Transaction *tran, Error **errp);
BlockDriverState *bdrv_insert_node(BlockDriverState *bs, QDict *node_options,
int flags, Error **errp);
int bdrv_drop_filter(BlockDriverState *bs, Error **errp);
diff --git a/block.c b/block.c
index 601fee163b..b2f55ff872 100644
--- a/block.c
+++ b/block.c
@@ -5204,19 +5204,39 @@ out:
return ret;
}
+static void bdrv_drained_clean(void *opaque)
+{
+ BlockDriverState *bs = opaque;
+
+ bdrv_drained_end(bs);
+ bdrv_unref(bs);
+}
+
+TransactionActionDrv bdrv_drained_drv = {
+ .clean = bdrv_drained_clean,
+};
+
+/*
+ * Start drained section on @bs, and finish it in .clean action.
+ * Reference to @bs is kept, so @bs can't be removed during transaction.
+ */
+static void bdrv_drained(BlockDriverState *bs, Transaction *tran)
+{
+ bdrv_ref(bs);
+ bdrv_drained_begin(bs);
+ tran_add(tran, &bdrv_drained_drv, bs);
+}
+
/* Not for empty child */
int bdrv_replace_child_bs(BdrvChild *child, BlockDriverState *new_bs,
- Error **errp)
+ Transaction *tran, Error **errp)
{
- int ret;
- Transaction *tran = tran_new();
g_autoptr(GHashTable) found = NULL;
g_autoptr(GSList) refresh_list = NULL;
BlockDriverState *old_bs = child->bs;
- bdrv_ref(old_bs);
- bdrv_drained_begin(old_bs);
- bdrv_drained_begin(new_bs);
+ bdrv_drained(old_bs, tran);
+ bdrv_drained(new_bs, tran);
bdrv_replace_child_tran(&child, new_bs, tran, true);
/* @new_bs must have been non-NULL, so @child must not have been freed */
@@ -5226,15 +5246,7 @@ int bdrv_replace_child_bs(BdrvChild *child, BlockDriverState
*new_bs,
refresh_list = bdrv_topological_dfs(refresh_list, found, old_bs);
refresh_list = bdrv_topological_dfs(refresh_list, found, new_bs);
- ret = bdrv_list_refresh_perms(refresh_list, NULL, tran, errp);
-
- tran_finalize(tran, ret);
-
- bdrv_drained_end(old_bs);
- bdrv_drained_end(new_bs);
- bdrv_unref(old_bs);
-
- return ret;
+ return bdrv_list_refresh_perms(refresh_list, NULL, tran, errp);
}
static void bdrv_delete(BlockDriverState *bs)
diff --git a/block/block-backend.c b/block/block-backend.c
index 97913acfcd..dbbbc56b2c 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -892,7 +892,13 @@ int blk_insert_bs(BlockBackend *blk, BlockDriverState *bs, Error
**errp)
*/
int blk_replace_bs(BlockBackend *blk, BlockDriverState *new_bs, Error **errp)
{
- return bdrv_replace_child_bs(blk->root, new_bs, errp);
+ int ret;
+ Transaction *tran = tran_new();
+
+ ret = bdrv_replace_child_bs(blk->root, new_bs, tran, errp);
+ tran_finalize(tran, ret);
+
+ return ret;
}
/*
--
2.31.1