diff options
| author | Ming Lei <ming.lei@redhat.com> | 2020-08-17 17:52:39 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-08-17 06:59:41 -0700 |
| commit | 943b40c832beb71115e38a1c4d99b640b5342738 (patch) | |
| tree | bad51d9f93dd0e6f0cd7e4acec5016f6acb62dab /block | |
| parent | bcb21c8cc9947286211327d663ace69f07d37a76 (diff) | |
| download | lwn-943b40c832beb71115e38a1c4d99b640b5342738.tar.gz lwn-943b40c832beb71115e38a1c4d99b640b5342738.zip | |
block: respect queue limit of max discard segment
When queue_max_discard_segments(q) is 1, blk_discard_mergable() will
return false for discard request, then normal request merge is applied.
However, only queue_max_segments() is checked, so max discard segment
limit isn't respected.
Check max discard segment limit in the request merge code for fixing
the issue.
Discard request failure of virtio_blk is fixed.
Fixes: 69840466086d ("block: fix the DISCARD request merge")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-merge.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/block/blk-merge.c b/block/blk-merge.c index 6529e3aab001..7af1f3668a91 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -533,10 +533,17 @@ int __blk_rq_map_sg(struct request_queue *q, struct request *rq, } EXPORT_SYMBOL(__blk_rq_map_sg); +static inline unsigned int blk_rq_get_max_segments(struct request *rq) +{ + if (req_op(rq) == REQ_OP_DISCARD) + return queue_max_discard_segments(rq->q); + return queue_max_segments(rq->q); +} + static inline int ll_new_hw_segment(struct request *req, struct bio *bio, unsigned int nr_phys_segs) { - if (req->nr_phys_segments + nr_phys_segs > queue_max_segments(req->q)) + if (req->nr_phys_segments + nr_phys_segs > blk_rq_get_max_segments(req)) goto no_merge; if (blk_integrity_merge_bio(req->q, req, bio) == false) @@ -624,7 +631,7 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req, return 0; total_phys_segments = req->nr_phys_segments + next->nr_phys_segments; - if (total_phys_segments > queue_max_segments(q)) + if (total_phys_segments > blk_rq_get_max_segments(req)) return 0; if (blk_integrity_merge_rq(q, req, next) == false) |