This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_recurse_can_replace() need to hold a reader lock for the graph
because it accesses the children list of a node.
Signed-off-by: Kevin Wolf <kw...@redhat.com>
Reviewed-by: Eric Blake <ebl...@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefa...@redhat.com>
---
include/block/block-global-state.h | 5 +++--
include/block/block_int-common.h | 4 ++--
include/block/block_int-global-state.h | 4 ++--
block/blkverify.c | 5 +++--
block/mirror.c | 4 ++++
block/quorum.c | 4 ++--
blockdev.c | 3 +++
7 files changed, 19 insertions(+), 10 deletions(-)
diff --git a/include/block/block-global-state.h
b/include/block/block-global-state.h
index ec3ddb17a8..f234bca0b6 100644
--- a/include/block/block-global-state.h
+++ b/include/block/block-global-state.h
@@ -163,8 +163,9 @@ int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts
*opts,
Error **errp);
/* check if a named node can be replaced when doing drive-mirror */
-BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs,
- const char *node_name, Error **errp);
+BlockDriverState * GRAPH_RDLOCK
+check_to_replace_node(BlockDriverState *parent_bs, const char *node_name,
+ Error **errp);
int no_coroutine_fn bdrv_activate(BlockDriverState *bs, Error **errp);
diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h
index 37d094796e..024ded4fc2 100644
--- a/include/block/block_int-common.h
+++ b/include/block/block_int-common.h
@@ -217,8 +217,8 @@ struct BlockDriver {
* same data as @bs without it affecting @bs's behavior (that is,
* without it being visible to @bs's parents).
*/
- bool (*bdrv_recurse_can_replace)(BlockDriverState *bs,
- BlockDriverState *to_replace);
+ bool GRAPH_RDLOCK_PTR (*bdrv_recurse_can_replace)(
+ BlockDriverState *bs, BlockDriverState *to_replace);
int (*bdrv_probe_device)(const char *filename);
diff --git a/include/block/block_int-global-state.h
b/include/block/block_int-global-state.h
index 902406eb99..da5fb31089 100644
--- a/include/block/block_int-global-state.h
+++ b/include/block/block_int-global-state.h
@@ -225,8 +225,8 @@ int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm,
uint64_t shared,
*/
int bdrv_child_refresh_perms(BlockDriverState *bs, BdrvChild *c, Error **errp);
-bool bdrv_recurse_can_replace(BlockDriverState *bs,
- BlockDriverState *to_replace);
+bool GRAPH_RDLOCK bdrv_recurse_can_replace(BlockDriverState *bs,
+ BlockDriverState *to_replace);
/*
* Default implementation for BlockDriver.bdrv_child_perm() that can
diff --git a/block/blkverify.c b/block/blkverify.c
index 1c16f86b2e..7326461f30 100644
--- a/block/blkverify.c
+++ b/block/blkverify.c
@@ -265,8 +265,9 @@ static int coroutine_fn GRAPH_RDLOCK
blkverify_co_flush(BlockDriverState *bs)
return bdrv_co_flush(s->test_file->bs);
}
-static bool blkverify_recurse_can_replace(BlockDriverState *bs,
- BlockDriverState *to_replace)
+static bool GRAPH_RDLOCK
+blkverify_recurse_can_replace(BlockDriverState *bs,
+ BlockDriverState *to_replace)
{
BDRVBlkverifyState *s = bs->opaque;
diff --git a/block/mirror.c b/block/mirror.c
index e48ed0af31..717442ca4d 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -747,7 +747,10 @@ static int mirror_exit_common(Job *job)
* Cannot use check_to_replace_node() here, because that would
* check for an op blocker on @to_replace, and we have our own
* there.
+ *
+ * TODO Pull out the writer lock from bdrv_replace_node() to here
*/
+ bdrv_graph_rdlock_main_loop();
if (bdrv_recurse_can_replace(src, to_replace)) {
bdrv_replace_node(to_replace, target_bs, &local_err);
} else {
@@ -756,6 +759,7 @@ static int mirror_exit_common(Job *job)
"would not lead to an abrupt change of visible data",
to_replace->node_name, target_bs->node_name);
}
+ bdrv_graph_rdunlock_main_loop();
bdrv_drained_end(target_bs);
if (local_err) {
error_report_err(local_err);
diff --git a/block/quorum.c b/block/quorum.c
index ff5a0a2da3..f28758cf2b 100644
--- a/block/quorum.c
+++ b/block/quorum.c
@@ -825,8 +825,8 @@ static coroutine_fn GRAPH_RDLOCK int
quorum_co_flush(BlockDriverState *bs)
return result;
}
-static bool quorum_recurse_can_replace(BlockDriverState *bs,
- BlockDriverState *to_replace)
+static bool GRAPH_RDLOCK
+quorum_recurse_can_replace(BlockDriverState *bs, BlockDriverState *to_replace)
{
BDRVQuorumState *s = bs->opaque;
int i;
diff --git a/blockdev.c b/blockdev.c
index e464daea58..d141ca7a2d 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2961,6 +2961,9 @@ static void blockdev_mirror_common(const char *job_id,
BlockDriverState *bs,
BlockDriverState *unfiltered_bs;
int job_flags = JOB_DEFAULT;
+ GLOBAL_STATE_CODE();
+ GRAPH_RDLOCK_GUARD_MAINLOOP();
+
if (!has_speed) {
speed = 0;
}
--
2.40.1
