block: Clarify locking rules for bdrv_open(_inherit)()

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>
master
Kevin Wolf 2023-05-25 14:47:03 +02:00
parent dea97c1fbd
commit ae400dbb8f
1 changed files with 2 additions and 8 deletions

10
block.c
View File

@ -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)
{