diff options
author | Kevin Wolf <kwolf@redhat.com> | 2023-10-27 17:53:13 +0200 |
---|---|---|
committer | Kevin Wolf <kwolf@redhat.com> | 2023-11-07 19:14:19 +0100 |
commit | 03b9eaca540322dd6dd4810aa57f3196ce971542 (patch) | |
tree | 44cca4b8180fe5271b3b710c46412cb447ab0f91 | |
parent | f5a3a270fe2b89d1be39f50ebdd15db80d59014b (diff) |
block: Mark bdrv_root_attach_child() GRAPH_WRLOCK
Instead of taking the writer lock internally, require callers to already
hold it when calling bdrv_root_attach_child(). These callers will
typically already hold the graph lock once the locking work is
completed, which means that they can't call functions that take it
internally.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231027155333.420094-5-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
-rw-r--r-- | block.c | 5 | ||||
-rw-r--r-- | block/block-backend.c | 2 | ||||
-rw-r--r-- | blockjob.c | 2 | ||||
-rw-r--r-- | include/block/block_int-global-state.h | 13 |
4 files changed, 12 insertions, 10 deletions
@@ -3214,8 +3214,6 @@ BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, GLOBAL_STATE_CODE(); - bdrv_graph_wrlock(child_bs); - child = bdrv_attach_child_common(child_bs, child_name, child_class, child_role, perm, shared_perm, opaque, tran, errp); @@ -3228,9 +3226,8 @@ BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, out: tran_finalize(tran, ret); - bdrv_graph_wrunlock(); - bdrv_unref(child_bs); + bdrv_schedule_unref(child_bs); return ret < 0 ? NULL : child; } diff --git a/block/block-backend.c b/block/block-backend.c index 53cf3bb8b8..075a0dfa95 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -931,10 +931,12 @@ int blk_insert_bs(BlockBackend *blk, BlockDriverState *bs, Error **errp) ThrottleGroupMember *tgm = &blk->public.throttle_group_member; GLOBAL_STATE_CODE(); bdrv_ref(bs); + bdrv_graph_wrlock(bs); blk->root = bdrv_root_attach_child(bs, "root", &child_root, BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, blk->perm, blk->shared_perm, blk, errp); + bdrv_graph_wrunlock(); if (blk->root == NULL) { return -EPERM; } diff --git a/blockjob.c b/blockjob.c index 5b24de356d..7920f6e500 100644 --- a/blockjob.c +++ b/blockjob.c @@ -248,8 +248,10 @@ int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs, } aio_context_acquire(ctx); } + bdrv_graph_wrlock(bs); c = bdrv_root_attach_child(bs, name, &child_job, 0, perm, shared_perm, job, errp); + bdrv_graph_wrunlock(); if (need_context_ops) { aio_context_release(ctx); if (job->job.aio_context != qemu_get_aio_context()) { diff --git a/include/block/block_int-global-state.h b/include/block/block_int-global-state.h index 074b677838..afce6c4416 100644 --- a/include/block/block_int-global-state.h +++ b/include/block/block_int-global-state.h @@ -196,12 +196,13 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, BlockCompletionFunc *cb, void *opaque, JobTxn *txn, Error **errp); -BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, - const char *child_name, - const BdrvChildClass *child_class, - BdrvChildRole child_role, - uint64_t perm, uint64_t shared_perm, - void *opaque, Error **errp); +BdrvChild * GRAPH_WRLOCK +bdrv_root_attach_child(BlockDriverState *child_bs, const char *child_name, + const BdrvChildClass *child_class, + BdrvChildRole child_role, + uint64_t perm, uint64_t shared_perm, + void *opaque, Error **errp); + void GRAPH_WRLOCK bdrv_root_unref_child(BdrvChild *child); void GRAPH_RDLOCK bdrv_get_cumulative_perm(BlockDriverState *bs, uint64_t *perm, |