diff options
| author | Christoph Hellwig <hch@lst.de> | 2015-09-27 21:01:50 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2015-10-01 10:10:55 +0200 |
| commit | f4829a9b7a61e159367350008a608b062c4f6840 (patch) | |
| tree | a2f488a95324e0c0b558273f48b18413ab2fa221 /block | |
| parent | 60de074ba1e8f327db19bc33d8530131ac01695d (diff) | |
blk-mq: fix racy updates of rq->errors
blk_mq_complete_request may be a no-op if the request has already
been completed by others means (e.g. a timeout or cancellation), but
currently drivers have to set rq->errors before calling
blk_mq_complete_request, which might leave us with the wrong error value.
Add an error parameter to blk_mq_complete_request so that we can
defer setting rq->errors until we known we won the race to complete the
request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-mq.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index 31c0c6259c4c..2306330530e8 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -393,14 +393,16 @@ void __blk_mq_complete_request(struct request *rq) * Ends all I/O on a request. It does not handle partial completions. * The actual completion happens out-of-order, through a IPI handler. **/ -void blk_mq_complete_request(struct request *rq) +void blk_mq_complete_request(struct request *rq, int error) { struct request_queue *q = rq->q; if (unlikely(blk_should_fake_timeout(q))) return; - if (!blk_mark_rq_complete(rq)) + if (!blk_mark_rq_complete(rq)) { + rq->errors = error; __blk_mq_complete_request(rq); + } } EXPORT_SYMBOL(blk_mq_complete_request); @@ -616,10 +618,8 @@ static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx, * If a request wasn't started before the queue was * marked dying, kill it here or it'll go unnoticed. */ - if (unlikely(blk_queue_dying(rq->q))) { - rq->errors = -EIO; - blk_mq_complete_request(rq); - } + if (unlikely(blk_queue_dying(rq->q))) + blk_mq_complete_request(rq, -EIO); return; } if (rq->cmd_flags & REQ_NO_TIMEOUT) |