diff options
Diffstat (limited to 'block/blk-merge.c')
| -rw-r--r-- | block/blk-merge.c | 52 |
1 files changed, 48 insertions, 4 deletions
diff --git a/block/blk-merge.c b/block/blk-merge.c index 35a8f75cc45d..1ac782fdc55c 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -276,7 +276,7 @@ static bool bvec_split_segs(const struct queue_limits *lim, * responsible for ensuring that @bs is only destroyed after processing of the * split bio has finished. */ -static struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim, +struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim, unsigned *segs, struct bio_set *bs, unsigned max_bytes) { struct bio_vec bv, bvprv, *bvprvp = NULL; @@ -309,6 +309,16 @@ static struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim, *segs = nsegs; return NULL; split: + /* + * We can't sanely support splitting for a REQ_NOWAIT bio. End it + * with EAGAIN if splitting is required and return an error pointer. + */ + if (bio->bi_opf & REQ_NOWAIT) { + bio->bi_status = BLK_STS_AGAIN; + bio_endio(bio); + return ERR_PTR(-EAGAIN); + } + *segs = nsegs; /* @@ -326,6 +336,7 @@ split: bio_clear_polled(bio); return bio_split(bio, bytes >> SECTOR_SHIFT, GFP_NOIO, bs); } +EXPORT_SYMBOL_GPL(bio_split_rw); /** * __bio_split_to_limits - split a bio to fit the queue limits @@ -358,11 +369,13 @@ struct bio *__bio_split_to_limits(struct bio *bio, default: split = bio_split_rw(bio, lim, nr_segs, bs, get_max_io_size(bio, lim) << SECTOR_SHIFT); + if (IS_ERR(split)) + return NULL; break; } if (split) { - /* there isn't chance to merge the splitted bio */ + /* there isn't chance to merge the split bio */ split->bi_opf |= REQ_NOMERGE; blkcg_bio_issue_init(split); @@ -745,6 +758,33 @@ void blk_rq_set_mixed_merge(struct request *rq) rq->rq_flags |= RQF_MIXED_MERGE; } +static inline blk_opf_t bio_failfast(const struct bio *bio) +{ + if (bio->bi_opf & REQ_RAHEAD) + return REQ_FAILFAST_MASK; + + return bio->bi_opf & REQ_FAILFAST_MASK; +} + +/* + * After we are marked as MIXED_MERGE, any new RA bio has to be updated + * as failfast, and request's failfast has to be updated in case of + * front merge. + */ +static inline void blk_update_mixed_merge(struct request *req, + struct bio *bio, bool front_merge) +{ + if (req->rq_flags & RQF_MIXED_MERGE) { + if (bio->bi_opf & REQ_RAHEAD) + bio->bi_opf |= REQ_FAILFAST_MASK; + + if (front_merge) { + req->cmd_flags &= ~REQ_FAILFAST_MASK; + req->cmd_flags |= bio->bi_opf & REQ_FAILFAST_MASK; + } + } +} + static void blk_account_io_merge_request(struct request *req) { if (blk_do_io_stat(req)) { @@ -942,7 +982,7 @@ enum bio_merge_status { static enum bio_merge_status bio_attempt_back_merge(struct request *req, struct bio *bio, unsigned int nr_segs) { - const blk_opf_t ff = bio->bi_opf & REQ_FAILFAST_MASK; + const blk_opf_t ff = bio_failfast(bio); if (!ll_back_merge_fn(req, bio, nr_segs)) return BIO_MERGE_FAILED; @@ -953,6 +993,8 @@ static enum bio_merge_status bio_attempt_back_merge(struct request *req, if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff) blk_rq_set_mixed_merge(req); + blk_update_mixed_merge(req, bio, false); + req->biotail->bi_next = bio; req->biotail = bio; req->__data_len += bio->bi_iter.bi_size; @@ -966,7 +1008,7 @@ static enum bio_merge_status bio_attempt_back_merge(struct request *req, static enum bio_merge_status bio_attempt_front_merge(struct request *req, struct bio *bio, unsigned int nr_segs) { - const blk_opf_t ff = bio->bi_opf & REQ_FAILFAST_MASK; + const blk_opf_t ff = bio_failfast(bio); if (!ll_front_merge_fn(req, bio, nr_segs)) return BIO_MERGE_FAILED; @@ -977,6 +1019,8 @@ static enum bio_merge_status bio_attempt_front_merge(struct request *req, if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff) blk_rq_set_mixed_merge(req); + blk_update_mixed_merge(req, bio, true); + bio->bi_next = req->bio; req->bio = bio; |