block: Acquire AioContexts during bdrv_reopen_multiple()

As the BlockReopenQueue can contain nodes in multiple AioContexts, only
one of which may be locked when AIO_WAIT_WHILE() can be called, we can't
let the caller lock the right contexts. Instead, individually lock the
AioContext of a single node when iterating the queue.

Reintroduce bdrv_reopen() as a wrapper for reopening a single node that
drains the node and temporarily drops the AioContext lock for
bdrv_reopen_multiple().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210708114709.206487-4-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2021-07-08 13:47:06 +02:00
parent ab5b522879
commit 6cf42ca2f9
5 changed files with 58 additions and 14 deletions

View file

@ -388,6 +388,8 @@ BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
bool keep_old_opts);
void bdrv_reopen_queue_free(BlockReopenQueue *bs_queue);
int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp);
int bdrv_reopen(BlockDriverState *bs, QDict *opts, bool keep_old_opts,
Error **errp);
int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only,
Error **errp);
int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset,