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[PULL 02/32] block: Clarify locking rules for bdrv_open(_inherit)()
From: |
Kevin Wolf |
Subject: |
[PULL 02/32] block: Clarify locking rules for bdrv_open(_inherit)() |
Date: |
Tue, 30 May 2023 18:32:09 +0200 |
These functions specify that the caller must hold the "@filename
AioContext lock". This doesn't make sense, file names don't have an
AioContext. New BlockDriverStates always start in the main AioContext,
so this is what we really need here.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230525124713.401149-3-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
block.c | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)
diff --git a/block.c b/block.c
index a2f8d5a0c0..6ac47112fe 100644
--- a/block.c
+++ b/block.c
@@ -3810,9 +3810,7 @@ out:
* should be opened. If specified, neither options nor a filename may be given,
* nor can an existing BDS be reused (that is, *pbs has to be NULL).
*
- * The caller must always hold @filename AioContext lock, because this
- * function eventually calls bdrv_refresh_total_sectors() which polls
- * when called from non-coroutine context.
+ * The caller must always hold the main AioContext lock.
*/
static BlockDriverState * no_coroutine_fn
bdrv_open_inherit(const char *filename, const char *reference, QDict *options,
@@ -4100,11 +4098,7 @@ close_and_fail:
return NULL;
}
-/*
- * The caller must always hold @filename AioContext lock, because this
- * function eventually calls bdrv_refresh_total_sectors() which polls
- * when called from non-coroutine context.
- */
+/* The caller must always hold the main AioContext lock. */
BlockDriverState *bdrv_open(const char *filename, const char *reference,
QDict *options, int flags, Error **errp)
{
--
2.40.1
- [PULL 00/32] Block layer patches, Kevin Wolf, 2023/05/30
- [PULL 06/32] qcow2: Fix open with 'file' in iothread, Kevin Wolf, 2023/05/30
- [PULL 05/32] mirror: Hold main AioContext lock for calling bdrv_open_backing_file(), Kevin Wolf, 2023/05/30
- [PULL 08/32] copy-before-write: Fix open with child in iothread, Kevin Wolf, 2023/05/30
- [PULL 03/32] block: Take main AioContext lock when calling bdrv_open(), Kevin Wolf, 2023/05/30
- [PULL 02/32] block: Clarify locking rules for bdrv_open(_inherit)(),
Kevin Wolf <=
- [PULL 01/32] block-coroutine-wrapper: Take AioContext lock in no_co_wrappers, Kevin Wolf, 2023/05/30
- [PULL 04/32] block-backend: Fix blk_new_open() for iothreads, Kevin Wolf, 2023/05/30
- [PULL 19/32] block/export: stop using is_external in vhost-user-blk server, Kevin Wolf, 2023/05/30
- [PULL 16/32] virtio-scsi: stop using aio_disable_external() during unplug, Kevin Wolf, 2023/05/30
- [PULL 15/32] virtio-scsi: avoid race between unplug and transport event, Kevin Wolf, 2023/05/30
- [PULL 17/32] util/vhost-user-server: rename refcount to in_flight counter, Kevin Wolf, 2023/05/30
- [PULL 18/32] block/export: wait for vhost-user-blk requests when draining, Kevin Wolf, 2023/05/30
- [PULL 24/32] hw/xen: do not set is_external=true on evtchn fds, Kevin Wolf, 2023/05/30
- [PULL 26/32] block/export: don't require AioContext lock around blk_exp_ref/unref(), Kevin Wolf, 2023/05/30
- [PULL 22/32] block: drain from main loop thread in bdrv_co_yield_to_drain(), Kevin Wolf, 2023/05/30