diff options
| author | Keith Busch <keith.busch@intel.com> | 2015-08-19 14:24:05 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2015-08-19 14:26:02 -0700 |
| commit | 03100aada96f0645bbcb89aea24c01f02d0ef1fa (patch) | |
| tree | ba909d035a188206b101ae633f925e18d749f7cc /block/blk-merge.c | |
| parent | d2be537c3ba3568acd79cd178327b842e60d035e (diff) | |
block: Replace SG_GAPS with new queue limits mask
The SG_GAPS queue flag caused checks for bio vector alignment against
PAGE_SIZE, but the device may have different constraints. This patch
adds a queue limits so a driver with such constraints can set to allow
requests that would have been unnecessarily split. The new gaps check
takes the request_queue as a parameter to simplify the logic around
invoking this function.
This new limit makes the queue flag redundant, so removing it and
all usage. Device-mappers will inherit the correct settings through
blk_stack_limits().
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'block/blk-merge.c')
| -rw-r--r-- | block/blk-merge.c | 23 |
1 files changed, 7 insertions, 16 deletions
diff --git a/block/blk-merge.c b/block/blk-merge.c index 0027def35f5a..0e0d9fd01c40 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -82,8 +82,7 @@ static struct bio *blk_bio_segment_split(struct request_queue *q, * If the queue doesn't support SG gaps and adding this * offset would create a gap, disallow it. */ - if (q->queue_flags & (1 << QUEUE_FLAG_SG_GAPS) && - prev && bvec_gap_to_prev(&bvprv, bv.bv_offset)) + if (prev && bvec_gap_to_prev(q, &bvprv, bv.bv_offset)) goto split; if (prev && blk_queue_cluster(q)) { @@ -484,12 +483,12 @@ static bool req_no_special_merge(struct request *req) return !q->mq_ops && req->special; } -static int req_gap_to_prev(struct request *req, struct request *next) +static int req_gap_to_prev(struct request *req, struct bio *next) { struct bio *prev = req->biotail; - return bvec_gap_to_prev(&prev->bi_io_vec[prev->bi_vcnt - 1], - next->bio->bi_io_vec[0].bv_offset); + return bvec_gap_to_prev(req->q, &prev->bi_io_vec[prev->bi_vcnt - 1], + next->bi_io_vec[1].bv_offset); } static int ll_merge_requests_fn(struct request_queue *q, struct request *req, @@ -506,8 +505,7 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req, if (req_no_special_merge(req) || req_no_special_merge(next)) return 0; - if (test_bit(QUEUE_FLAG_SG_GAPS, &q->queue_flags) && - req_gap_to_prev(req, next)) + if (req_gap_to_prev(req, next->bio)) return 0; /* @@ -692,8 +690,6 @@ int blk_attempt_req_merge(struct request_queue *q, struct request *rq, bool blk_rq_merge_ok(struct request *rq, struct bio *bio) { - struct request_queue *q = rq->q; - if (!rq_mergeable(rq) || !bio_mergeable(bio)) return false; @@ -718,13 +714,8 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio) return false; /* Only check gaps if the bio carries data */ - if (q->queue_flags & (1 << QUEUE_FLAG_SG_GAPS) && bio_has_data(bio)) { - struct bio_vec *bprev; - - bprev = &rq->biotail->bi_io_vec[rq->biotail->bi_vcnt - 1]; - if (bvec_gap_to_prev(bprev, bio->bi_io_vec[0].bv_offset)) - return false; - } + if (bio_has_data(bio) && req_gap_to_prev(rq, bio)) + return false; return true; } |