diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/ll_rw_blk.c | 102 |
1 files changed, 44 insertions, 58 deletions
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index ed39313c408..e35119a72a4 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -42,6 +42,7 @@ static void drive_stat_acct(struct request *rq, int nr_sectors, int new_io); static void init_request_from_bio(struct request *req, struct bio *bio); static int __make_request(struct request_queue *q, struct bio *bio); static struct io_context *current_io_context(gfp_t gfp_flags, int node); +static void blk_recalc_rq_segments(struct request *rq); /* * For the allocated request tables @@ -1220,16 +1221,42 @@ EXPORT_SYMBOL(blk_dump_rq_flags); void blk_recount_segments(struct request_queue *q, struct bio *bio) { + struct request rq; + struct bio *nxt = bio->bi_next; + rq.q = q; + rq.bio = rq.biotail = bio; + bio->bi_next = NULL; + blk_recalc_rq_segments(&rq); + bio->bi_next = nxt; + bio->bi_phys_segments = rq.nr_phys_segments; + bio->bi_hw_segments = rq.nr_hw_segments; + bio->bi_flags |= (1 << BIO_SEG_VALID); +} +EXPORT_SYMBOL(blk_recount_segments); + +static void blk_recalc_rq_segments(struct request *rq) +{ + int nr_phys_segs; + int nr_hw_segs; + unsigned int phys_size; + unsigned int hw_size; struct bio_vec *bv, *bvprv = NULL; - int i, nr_phys_segs, nr_hw_segs, seg_size, hw_seg_size, cluster; + int seg_size; + int hw_seg_size; + int cluster; + struct bio *bio; + int i; int high, highprv = 1; + struct request_queue *q = rq->q; - if (unlikely(!bio->bi_io_vec)) + if (!rq->bio) return; cluster = q->queue_flags & (1 << QUEUE_FLAG_CLUSTER); - hw_seg_size = seg_size = nr_phys_segs = nr_hw_segs = 0; - bio_for_each_segment(bv, bio, i) { + hw_seg_size = seg_size = 0; + phys_size = hw_size = nr_phys_segs = nr_hw_segs = 0; + rq_for_each_bio(bio, rq) + bio_for_each_segment(bv, bio, i) { /* * the trick here is making sure that a high page is never * considered part of another segment, since that might @@ -1255,12 +1282,13 @@ void blk_recount_segments(struct request_queue *q, struct bio *bio) } new_segment: if (BIOVEC_VIRT_MERGEABLE(bvprv, bv) && - !BIOVEC_VIRT_OVERSIZE(hw_seg_size + bv->bv_len)) { + !BIOVEC_VIRT_OVERSIZE(hw_seg_size + bv->bv_len)) hw_seg_size += bv->bv_len; - } else { + else { new_hw_segment: - if (hw_seg_size > bio->bi_hw_front_size) - bio->bi_hw_front_size = hw_seg_size; + if (nr_hw_segs == 1 && + hw_seg_size > rq->bio->bi_hw_front_size) + rq->bio->bi_hw_front_size = hw_seg_size; hw_seg_size = BIOVEC_VIRT_START_SIZE(bv) + bv->bv_len; nr_hw_segs++; } @@ -1270,15 +1298,15 @@ new_hw_segment: seg_size = bv->bv_len; highprv = high; } - if (hw_seg_size > bio->bi_hw_back_size) - bio->bi_hw_back_size = hw_seg_size; - if (nr_hw_segs == 1 && hw_seg_size > bio->bi_hw_front_size) - bio->bi_hw_front_size = hw_seg_size; - bio->bi_phys_segments = nr_phys_segs; - bio->bi_hw_segments = nr_hw_segs; - bio->bi_flags |= (1 << BIO_SEG_VALID); + + if (nr_hw_segs == 1 && + hw_seg_size > rq->bio->bi_hw_front_size) + rq->bio->bi_hw_front_size = hw_seg_size; + if (hw_seg_size > rq->biotail->bi_hw_back_size) + rq->biotail->bi_hw_back_size = hw_seg_size; + rq->nr_phys_segments = nr_phys_segs; + rq->nr_hw_segments = nr_hw_segs; } -EXPORT_SYMBOL(blk_recount_segments); static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio, struct bio *nxt) @@ -3329,48 +3357,6 @@ void submit_bio(int rw, struct bio *bio) EXPORT_SYMBOL(submit_bio); -static void blk_recalc_rq_segments(struct request *rq) -{ - struct bio *bio, *prevbio = NULL; - int nr_phys_segs, nr_hw_segs; - unsigned int phys_size, hw_size; - struct request_queue *q = rq->q; - - if (!rq->bio) - return; - - phys_size = hw_size = nr_phys_segs = nr_hw_segs = 0; - rq_for_each_bio(bio, rq) { - /* Force bio hw/phys segs to be recalculated. */ - bio->bi_flags &= ~(1 << BIO_SEG_VALID); - - nr_phys_segs += bio_phys_segments(q, bio); - nr_hw_segs += bio_hw_segments(q, bio); - if (prevbio) { - int pseg = phys_size + prevbio->bi_size + bio->bi_size; - int hseg = hw_size + prevbio->bi_size + bio->bi_size; - - if (blk_phys_contig_segment(q, prevbio, bio) && - pseg <= q->max_segment_size) { - nr_phys_segs--; - phys_size += prevbio->bi_size + bio->bi_size; - } else - phys_size = 0; - - if (blk_hw_contig_segment(q, prevbio, bio) && - hseg <= q->max_segment_size) { - nr_hw_segs--; - hw_size += prevbio->bi_size + bio->bi_size; - } else - hw_size = 0; - } - prevbio = bio; - } - - rq->nr_phys_segments = nr_phys_segs; - rq->nr_hw_segments = nr_hw_segs; -} - static void blk_recalc_rq_sectors(struct request *rq, int nsect) { if (blk_fs_request(rq)) { |