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| author | Martin K. Petersen <martin.petersen@oracle.com> | 2012-09-18 12:19:26 -0400 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2012-09-20 14:31:41 +0200 |
| commit | f31dc1cd490539e2b62a126bc4dc2495b165d772 (patch) | |
| tree | e8a917161111266f72a7aea539c9562dc2f2653d /block | |
| parent | e2a60da74fc8215c68509a89e9a69c66363153db (diff) | |
| download | kernel-common-f31dc1cd490539e2b62a126bc4dc2495b165d772.tar.gz kernel-common-f31dc1cd490539e2b62a126bc4dc2495b165d772.tar.bz2 kernel-common-f31dc1cd490539e2b62a126bc4dc2495b165d772.zip | |
block: Consolidate command flag and queue limit checks for merges
- blk_check_merge_flags() verifies that cmd_flags / bi_rw are
compatible. This function is called for both req-req and req-bio
merging.
- blk_rq_get_max_sectors() and blk_queue_get_max_sectors() can be used
to query the maximum sector count for a given request or queue. The
calls will return the right value from the queue limits given the
type of command (RW, discard, write same, etc.)
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-core.c | 3 | ||||
| -rw-r--r-- | block/blk-merge.c | 30 |
2 files changed, 13 insertions, 20 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index 5cc29299f6ac..33eded00c5b1 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1866,8 +1866,7 @@ int blk_rq_check_limits(struct request_queue *q, struct request *rq) if (!rq_mergeable(rq)) return 0; - if (blk_rq_sectors(rq) > queue_max_sectors(q) || - blk_rq_bytes(rq) > queue_max_hw_sectors(q) << 9) { + if (blk_rq_sectors(rq) > blk_queue_get_max_sectors(q, rq->cmd_flags)) { printk(KERN_ERR "%s: over max size limit.\n", __func__); return -EIO; } diff --git a/block/blk-merge.c b/block/blk-merge.c index 86710ca408b8..642b862608a1 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -275,14 +275,8 @@ no_merge: int ll_back_merge_fn(struct request_queue *q, struct request *req, struct bio *bio) { - unsigned short max_sectors; - - if (unlikely(req->cmd_type == REQ_TYPE_BLOCK_PC)) - max_sectors = queue_max_hw_sectors(q); - else - max_sectors = queue_max_sectors(q); - - if (blk_rq_sectors(req) + bio_sectors(bio) > max_sectors) { + if (blk_rq_sectors(req) + bio_sectors(bio) > + blk_rq_get_max_sectors(req)) { req->cmd_flags |= REQ_NOMERGE; if (req == q->last_merge) q->last_merge = NULL; @@ -299,15 +293,8 @@ int ll_back_merge_fn(struct request_queue *q, struct request *req, int ll_front_merge_fn(struct request_queue *q, struct request *req, struct bio *bio) { - unsigned short max_sectors; - - if (unlikely(req->cmd_type == REQ_TYPE_BLOCK_PC)) - max_sectors = queue_max_hw_sectors(q); - else - max_sectors = queue_max_sectors(q); - - - if (blk_rq_sectors(req) + bio_sectors(bio) > max_sectors) { + if (blk_rq_sectors(req) + bio_sectors(bio) > + blk_rq_get_max_sectors(req)) { req->cmd_flags |= REQ_NOMERGE; if (req == q->last_merge) q->last_merge = NULL; @@ -338,7 +325,8 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req, /* * Will it become too large? */ - if ((blk_rq_sectors(req) + blk_rq_sectors(next)) > queue_max_sectors(q)) + if ((blk_rq_sectors(req) + blk_rq_sectors(next)) > + blk_rq_get_max_sectors(req)) return 0; total_phys_segments = req->nr_phys_segments + next->nr_phys_segments; @@ -417,6 +405,9 @@ static int attempt_merge(struct request_queue *q, struct request *req, if (!rq_mergeable(req) || !rq_mergeable(next)) return 0; + if (!blk_check_merge_flags(req->cmd_flags, next->cmd_flags)) + return 0; + /* * not contiguous */ @@ -512,6 +503,9 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio) if (!rq_mergeable(rq) || !bio_mergeable(bio)) return false; + if (!blk_check_merge_flags(rq->cmd_flags, bio->bi_rw)) + return false; + /* different data direction or already started, don't merge */ if (bio_data_dir(bio) != rq_data_dir(rq)) return false; |