From 7a67f63b3233ff28e753854fe27891c44f8588ae Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 8 Aug 2008 11:17:12 +0200 Subject: block: add bio_has_data() to detect whether a bio carries data or not Signed-off-by: Jens Axboe --- include/linux/bio.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/linux/bio.h') diff --git a/include/linux/bio.h b/include/linux/bio.h index 0933a14e641..9e93c929947 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -445,6 +445,14 @@ static inline char *__bio_kmap_irq(struct bio *bio, unsigned short idx, __bio_kmap_irq((bio), (bio)->bi_idx, (flags)) #define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags) +/* + * Check whether this bio carries any data or not. A NULL bio is allowed. + */ +static inline int bio_has_data(struct bio *bio) +{ + return bio && bio->bi_io_vec != NULL; +} + #if defined(CONFIG_BLK_DEV_INTEGRITY) #define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)])) -- cgit v1.2.3-70-g09d2 From a9c701e594669dd49fed448c27c64f20cfacc8a7 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 8 Aug 2008 11:04:44 +0200 Subject: block: use bio_has_data() to check for data carrying bio Signed-off-by: Jens Axboe --- block/blk-core.c | 5 +---- include/linux/bio.h | 2 +- 2 files changed, 2 insertions(+), 5 deletions(-) (limited to 'include/linux/bio.h') diff --git a/block/blk-core.c b/block/blk-core.c index 2cba5ef97b2..54e442ba44a 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1490,10 +1490,7 @@ void submit_bio(int rw, struct bio *bio) * If it's a regular read/write or a barrier with data attached, * go through the normal accounting stuff before submission. */ - if (!bio_empty_barrier(bio)) { - - BIO_BUG_ON(!bio->bi_size); - BIO_BUG_ON(!bio->bi_io_vec); + if (bio_has_data(bio)) { if (rw & WRITE) { count_vm_events(PGPGOUT, count); diff --git a/include/linux/bio.h b/include/linux/bio.h index 9e93c929947..dbeb66f813a 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -185,7 +185,7 @@ struct bio { #define bio_failfast(bio) ((bio)->bi_rw & (1 << BIO_RW_FAILFAST)) #define bio_rw_ahead(bio) ((bio)->bi_rw & (1 << BIO_RW_AHEAD)) #define bio_rw_meta(bio) ((bio)->bi_rw & (1 << BIO_RW_META)) -#define bio_empty_barrier(bio) (bio_barrier(bio) && !(bio)->bi_size) +#define bio_empty_barrier(bio) (bio_barrier(bio) && !bio_has_data(bio)) static inline unsigned int bio_cur_sectors(struct bio *bio) { -- cgit v1.2.3-70-g09d2 From d628eaef310533767ce68664873869c2d7f78f09 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Sat, 9 Aug 2008 16:22:17 +0100 Subject: Fix up comments about matching flags between bio and rq Signed-off-by: David Woodhouse Signed-off-by: Jens Axboe --- block/blk-core.c | 7 ++----- include/linux/bio.h | 4 ++-- include/linux/blkdev.h | 2 +- 3 files changed, 5 insertions(+), 8 deletions(-) (limited to 'include/linux/bio.h') diff --git a/block/blk-core.c b/block/blk-core.c index b5776c1fd52..a496727df7e 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -624,10 +624,6 @@ blk_alloc_request(struct request_queue *q, int rw, int priv, gfp_t gfp_mask) blk_rq_init(q, rq); - /* - * first three bits are identical in rq->cmd_flags and bio->bi_rw, - * see bio.h and blkdev.h - */ rq->cmd_flags = rw | REQ_ALLOCED; if (priv) { @@ -2012,7 +2008,8 @@ EXPORT_SYMBOL_GPL(blk_end_request_callback); void blk_rq_bio_prep(struct request_queue *q, struct request *rq, struct bio *bio) { - /* first two bits are identical in rq->cmd_flags and bio->bi_rw */ + /* Bit 0 (R/W) is identical in rq->cmd_flags and bio->bi_rw, and + we want BIO_RW_AHEAD (bit 1) to imply REQ_FAILFAST (bit 1). */ rq->cmd_flags |= (bio->bi_rw & 3); rq->nr_phys_segments = bio_phys_segments(q, bio); diff --git a/include/linux/bio.h b/include/linux/bio.h index dbeb66f813a..17f1fbdb31b 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -150,8 +150,8 @@ struct bio { * bit 3 -- fail fast, don't want low level driver retries * bit 4 -- synchronous I/O hint: the block layer will unplug immediately */ -#define BIO_RW 0 -#define BIO_RW_AHEAD 1 +#define BIO_RW 0 /* Must match RW in req flags (blkdev.h) */ +#define BIO_RW_AHEAD 1 /* Must match FAILFAST in req flags */ #define BIO_RW_BARRIER 2 #define BIO_RW_FAILFAST 3 #define BIO_RW_SYNC 4 diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 53ea933cf60..e0ba018f5e8 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -84,7 +84,7 @@ enum { }; /* - * request type modified bits. first three bits match BIO_RW* bits, important + * request type modified bits. first two bits match BIO_RW* bits, important */ enum rq_flag_bits { __REQ_RW, /* not set, read. set, write */ -- cgit v1.2.3-70-g09d2 From fb2dce862d9f9a68e6b9374579056ec9eca02a63 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Tue, 5 Aug 2008 18:01:53 +0100 Subject: Add 'discard' request handling Some block devices benefit from a hint that they can forget the contents of certain sectors. Add basic support for this to the block core, along with a 'blkdev_issue_discard()' helper function which issues such requests. The caller doesn't get to provide an end_io functio, since blkdev_issue_discard() will automatically split the request up into multiple bios if appropriate. Neither does the function wait for completion -- it's expected that callers won't care about when, or even _if_, the request completes. It's only a hint to the device anyway. By definition, the file system doesn't _care_ about these sectors any more. [With feedback from OGAWA Hirofumi and Jens Axboe Signed-off-by: Jens Axboe --- block/blk-barrier.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++++++ block/blk-core.c | 28 ++++++++++++++------ block/blk-settings.c | 17 +++++++++++++ include/linux/bio.h | 8 ++++-- include/linux/blkdev.h | 16 ++++++++++++ include/linux/fs.h | 3 ++- 6 files changed, 130 insertions(+), 11 deletions(-) (limited to 'include/linux/bio.h') diff --git a/block/blk-barrier.c b/block/blk-barrier.c index a09ead19f9c..273121c0eb8 100644 --- a/block/blk-barrier.c +++ b/block/blk-barrier.c @@ -315,3 +315,72 @@ int blkdev_issue_flush(struct block_device *bdev, sector_t *error_sector) return ret; } EXPORT_SYMBOL(blkdev_issue_flush); + +static void blkdev_discard_end_io(struct bio *bio, int err) +{ + if (err) { + if (err == -EOPNOTSUPP) + set_bit(BIO_EOPNOTSUPP, &bio->bi_flags); + clear_bit(BIO_UPTODATE, &bio->bi_flags); + } + + bio_put(bio); +} + +/** + * blkdev_issue_discard - queue a discard + * @bdev: blockdev to issue discard for + * @sector: start sector + * @nr_sects: number of sectors to discard + * + * Description: + * Issue a discard request for the sectors in question. Does not wait. + */ +int blkdev_issue_discard(struct block_device *bdev, sector_t sector, + unsigned nr_sects) +{ + struct request_queue *q; + struct bio *bio; + int ret = 0; + + if (bdev->bd_disk == NULL) + return -ENXIO; + + q = bdev_get_queue(bdev); + if (!q) + return -ENXIO; + + if (!q->prepare_discard_fn) + return -EOPNOTSUPP; + + while (nr_sects && !ret) { + bio = bio_alloc(GFP_KERNEL, 0); + if (!bio) + return -ENOMEM; + + bio->bi_end_io = blkdev_discard_end_io; + bio->bi_bdev = bdev; + + bio->bi_sector = sector; + + if (nr_sects > q->max_hw_sectors) { + bio->bi_size = q->max_hw_sectors << 9; + nr_sects -= q->max_hw_sectors; + sector += q->max_hw_sectors; + } else { + bio->bi_size = nr_sects << 9; + nr_sects = 0; + } + bio_get(bio); + submit_bio(WRITE_DISCARD, bio); + + /* Check if it failed immediately */ + if (bio_flagged(bio, BIO_EOPNOTSUPP)) + ret = -EOPNOTSUPP; + else if (!bio_flagged(bio, BIO_UPTODATE)) + ret = -EIO; + bio_put(bio); + } + return ret; +} +EXPORT_SYMBOL(blkdev_issue_discard); diff --git a/block/blk-core.c b/block/blk-core.c index a496727df7e..1e143c4f9d3 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1079,6 +1079,10 @@ void init_request_from_bio(struct request *req, struct bio *bio) */ if (unlikely(bio_barrier(bio))) req->cmd_flags |= (REQ_HARDBARRIER | REQ_NOMERGE); + if (unlikely(bio_discard(bio))) { + req->cmd_flags |= (REQ_SOFTBARRIER | REQ_DISCARD); + req->q->prepare_discard_fn(req->q, req); + } if (bio_sync(bio)) req->cmd_flags |= REQ_RW_SYNC; @@ -1095,7 +1099,7 @@ void init_request_from_bio(struct request *req, struct bio *bio) static int __make_request(struct request_queue *q, struct bio *bio) { struct request *req; - int el_ret, nr_sectors, barrier, err; + int el_ret, nr_sectors, barrier, discard, err; const unsigned short prio = bio_prio(bio); const int sync = bio_sync(bio); int rw_flags; @@ -1115,6 +1119,12 @@ static int __make_request(struct request_queue *q, struct bio *bio) goto end_io; } + discard = bio_discard(bio); + if (unlikely(discard) && !q->prepare_discard_fn) { + err = -EOPNOTSUPP; + goto end_io; + } + spin_lock_irq(q->queue_lock); if (unlikely(barrier) || elv_queue_empty(q)) @@ -1405,7 +1415,8 @@ end_io: if (bio_check_eod(bio, nr_sectors)) goto end_io; - if (bio_empty_barrier(bio) && !q->prepare_flush_fn) { + if ((bio_empty_barrier(bio) && !q->prepare_flush_fn) || + (bio_discard(bio) && !q->prepare_discard_fn)) { err = -EOPNOTSUPP; goto end_io; } @@ -1487,7 +1498,6 @@ void submit_bio(int rw, struct bio *bio) * go through the normal accounting stuff before submission. */ if (bio_has_data(bio)) { - if (rw & WRITE) { count_vm_events(PGPGOUT, count); } else { @@ -1881,7 +1891,7 @@ static int blk_end_io(struct request *rq, int error, unsigned int nr_bytes, struct request_queue *q = rq->q; unsigned long flags = 0UL; - if (bio_has_data(rq->bio)) { + if (bio_has_data(rq->bio) || blk_discard_rq(rq)) { if (__end_that_request_first(rq, error, nr_bytes)) return 1; @@ -1939,7 +1949,7 @@ EXPORT_SYMBOL_GPL(blk_end_request); **/ int __blk_end_request(struct request *rq, int error, unsigned int nr_bytes) { - if (bio_has_data(rq->bio) && + if ((bio_has_data(rq->bio) || blk_discard_rq(rq)) && __end_that_request_first(rq, error, nr_bytes)) return 1; @@ -2012,12 +2022,14 @@ void blk_rq_bio_prep(struct request_queue *q, struct request *rq, we want BIO_RW_AHEAD (bit 1) to imply REQ_FAILFAST (bit 1). */ rq->cmd_flags |= (bio->bi_rw & 3); - rq->nr_phys_segments = bio_phys_segments(q, bio); - rq->nr_hw_segments = bio_hw_segments(q, bio); + if (bio_has_data(bio)) { + rq->nr_phys_segments = bio_phys_segments(q, bio); + rq->nr_hw_segments = bio_hw_segments(q, bio); + rq->buffer = bio_data(bio); + } rq->current_nr_sectors = bio_cur_sectors(bio); rq->hard_cur_sectors = rq->current_nr_sectors; rq->hard_nr_sectors = rq->nr_sectors = bio_sectors(bio); - rq->buffer = bio_data(bio); rq->data_len = bio->bi_size; rq->bio = rq->biotail = bio; diff --git a/block/blk-settings.c b/block/blk-settings.c index dfc77012843..539d873c820 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -32,6 +32,23 @@ void blk_queue_prep_rq(struct request_queue *q, prep_rq_fn *pfn) } EXPORT_SYMBOL(blk_queue_prep_rq); +/** + * blk_queue_set_discard - set a discard_sectors function for queue + * @q: queue + * @dfn: prepare_discard function + * + * It's possible for a queue to register a discard callback which is used + * to transform a discard request into the appropriate type for the + * hardware. If none is registered, then discard requests are failed + * with %EOPNOTSUPP. + * + */ +void blk_queue_set_discard(struct request_queue *q, prepare_discard_fn *dfn) +{ + q->prepare_discard_fn = dfn; +} +EXPORT_SYMBOL(blk_queue_set_discard); + /** * blk_queue_merge_bvec - set a merge_bvec function for queue * @q: queue diff --git a/include/linux/bio.h b/include/linux/bio.h index 17f1fbdb31b..1fdfc5621c8 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -149,6 +149,8 @@ struct bio { * bit 2 -- barrier * bit 3 -- fail fast, don't want low level driver retries * bit 4 -- synchronous I/O hint: the block layer will unplug immediately + * bit 5 -- metadata request + * bit 6 -- discard sectors */ #define BIO_RW 0 /* Must match RW in req flags (blkdev.h) */ #define BIO_RW_AHEAD 1 /* Must match FAILFAST in req flags */ @@ -156,6 +158,7 @@ struct bio { #define BIO_RW_FAILFAST 3 #define BIO_RW_SYNC 4 #define BIO_RW_META 5 +#define BIO_RW_DISCARD 6 /* * upper 16 bits of bi_rw define the io priority of this bio @@ -186,13 +189,14 @@ struct bio { #define bio_rw_ahead(bio) ((bio)->bi_rw & (1 << BIO_RW_AHEAD)) #define bio_rw_meta(bio) ((bio)->bi_rw & (1 << BIO_RW_META)) #define bio_empty_barrier(bio) (bio_barrier(bio) && !bio_has_data(bio)) +#define bio_discard(bio) ((bio)->bi_rw & (1 << BIO_RW_DISCARD)) static inline unsigned int bio_cur_sectors(struct bio *bio) { if (bio->bi_vcnt) return bio_iovec(bio)->bv_len >> 9; - - return 0; + else /* dataless requests such as discard */ + return bio->bi_size >> 9; } static inline void *bio_data(struct bio *bio) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index e0ba018f5e8..26ececbbebe 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -89,6 +89,7 @@ enum { enum rq_flag_bits { __REQ_RW, /* not set, read. set, write */ __REQ_FAILFAST, /* no low level driver retries */ + __REQ_DISCARD, /* request to discard sectors */ __REQ_SORTED, /* elevator knows about this request */ __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */ __REQ_HARDBARRIER, /* may not be passed by drive either */ @@ -111,6 +112,7 @@ enum rq_flag_bits { }; #define REQ_RW (1 << __REQ_RW) +#define REQ_DISCARD (1 << __REQ_DISCARD) #define REQ_FAILFAST (1 << __REQ_FAILFAST) #define REQ_SORTED (1 << __REQ_SORTED) #define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER) @@ -252,6 +254,7 @@ typedef void (request_fn_proc) (struct request_queue *q); typedef int (make_request_fn) (struct request_queue *q, struct bio *bio); typedef int (prep_rq_fn) (struct request_queue *, struct request *); typedef void (unplug_fn) (struct request_queue *); +typedef int (prepare_discard_fn) (struct request_queue *, struct request *); struct bio_vec; struct bvec_merge_data { @@ -307,6 +310,7 @@ struct request_queue make_request_fn *make_request_fn; prep_rq_fn *prep_rq_fn; unplug_fn *unplug_fn; + prepare_discard_fn *prepare_discard_fn; merge_bvec_fn *merge_bvec_fn; prepare_flush_fn *prepare_flush_fn; softirq_done_fn *softirq_done_fn; @@ -546,6 +550,7 @@ enum { #define blk_sorted_rq(rq) ((rq)->cmd_flags & REQ_SORTED) #define blk_barrier_rq(rq) ((rq)->cmd_flags & REQ_HARDBARRIER) #define blk_fua_rq(rq) ((rq)->cmd_flags & REQ_FUA) +#define blk_discard_rq(rq) ((rq)->cmd_flags & REQ_DISCARD) #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) #define blk_empty_barrier(rq) (blk_barrier_rq(rq) && blk_fs_request(rq) && !(rq)->hard_nr_sectors) /* rq->queuelist of dequeued request must be list_empty() */ @@ -796,6 +801,7 @@ extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *); extern void blk_queue_dma_alignment(struct request_queue *, int); extern void blk_queue_update_dma_alignment(struct request_queue *, int); extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); +extern void blk_queue_set_discard(struct request_queue *, prepare_discard_fn *); extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); extern int blk_queue_ordered(struct request_queue *, unsigned, prepare_flush_fn *); extern int blk_do_ordered(struct request_queue *, struct request **); @@ -837,6 +843,16 @@ static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, } extern int blkdev_issue_flush(struct block_device *, sector_t *); +extern int blkdev_issue_discard(struct block_device *, sector_t sector, + unsigned nr_sects); + +static inline int sb_issue_discard(struct super_block *sb, + sector_t block, unsigned nr_blocks) +{ + block <<= (sb->s_blocksize_bits - 9); + nr_blocks <<= (sb->s_blocksize_bits - 9); + return blkdev_issue_discard(sb->s_bdev, block, nr_blocks); +} /* * command filter functions diff --git a/include/linux/fs.h b/include/linux/fs.h index 580b513668f..eb013131913 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -86,7 +86,8 @@ extern int dir_notify_enable; #define READ_META (READ | (1 << BIO_RW_META)) #define WRITE_SYNC (WRITE | (1 << BIO_RW_SYNC)) #define SWRITE_SYNC (SWRITE | (1 << BIO_RW_SYNC)) -#define WRITE_BARRIER ((1 << BIO_RW) | (1 << BIO_RW_BARRIER)) +#define WRITE_BARRIER (WRITE | (1 << BIO_RW_BARRIER)) +#define WRITE_DISCARD (WRITE | (1 << BIO_RW_DISCARD)) #define SEL_IN 1 #define SEL_OUT 2 -- cgit v1.2.3-70-g09d2 From e17fc0a1ccf88f6d4dcb363729f3141b0958c325 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Sat, 9 Aug 2008 16:42:20 +0100 Subject: Allow elevators to sort/merge discard requests MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit But blkdev_issue_discard() still emits requests which are interpreted as soft barriers, because naïve callers might otherwise issue subsequent writes to those same sectors, which might cross on the queue (if they're reallocated quickly enough). Callers still _can_ issue non-barrier discard requests, but they have to take care of queue ordering for themselves. Signed-off-by: David Woodhouse Signed-off-by: Jens Axboe --- block/blk-barrier.c | 2 +- block/blk-core.c | 12 +++++++----- block/blk-merge.c | 27 +++++++++++++++++---------- block/elevator.c | 12 ++++++++++-- block/ioctl.c | 2 +- include/linux/bio.h | 2 +- include/linux/blkdev.h | 5 +++-- include/linux/fs.h | 3 ++- 8 files changed, 42 insertions(+), 23 deletions(-) (limited to 'include/linux/bio.h') diff --git a/block/blk-barrier.c b/block/blk-barrier.c index e5448131d4f..988b63479b2 100644 --- a/block/blk-barrier.c +++ b/block/blk-barrier.c @@ -372,7 +372,7 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, nr_sects = 0; } bio_get(bio); - submit_bio(WRITE_DISCARD, bio); + submit_bio(DISCARD_BARRIER, bio); /* Check if it failed immediately */ if (bio_flagged(bio, BIO_EOPNOTSUPP)) diff --git a/block/blk-core.c b/block/blk-core.c index 1e143c4f9d3..1261516dd42 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1077,12 +1077,13 @@ void init_request_from_bio(struct request *req, struct bio *bio) /* * REQ_BARRIER implies no merging, but lets make it explicit */ - if (unlikely(bio_barrier(bio))) - req->cmd_flags |= (REQ_HARDBARRIER | REQ_NOMERGE); if (unlikely(bio_discard(bio))) { - req->cmd_flags |= (REQ_SOFTBARRIER | REQ_DISCARD); + req->cmd_flags |= REQ_DISCARD; + if (bio_barrier(bio)) + req->cmd_flags |= REQ_SOFTBARRIER; req->q->prepare_discard_fn(req->q, req); - } + } else if (unlikely(bio_barrier(bio))) + req->cmd_flags |= (REQ_HARDBARRIER | REQ_NOMERGE); if (bio_sync(bio)) req->cmd_flags |= REQ_RW_SYNC; @@ -1114,7 +1115,8 @@ static int __make_request(struct request_queue *q, struct bio *bio) blk_queue_bounce(q, &bio); barrier = bio_barrier(bio); - if (unlikely(barrier) && (q->next_ordered == QUEUE_ORDERED_NONE)) { + if (unlikely(barrier) && bio_has_data(bio) && + (q->next_ordered == QUEUE_ORDERED_NONE)) { err = -EOPNOTSUPP; goto end_io; } diff --git a/block/blk-merge.c b/block/blk-merge.c index 5efc9e7a68b..6cf8f0c70a5 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -11,7 +11,7 @@ void blk_recalc_rq_sectors(struct request *rq, int nsect) { - if (blk_fs_request(rq)) { + if (blk_fs_request(rq) || blk_discard_rq(rq)) { rq->hard_sector += nsect; rq->hard_nr_sectors -= nsect; @@ -131,13 +131,17 @@ static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio, if (!test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags)) return 0; - if (!BIOVEC_PHYS_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt))) - return 0; if (bio->bi_size + nxt->bi_size > q->max_segment_size) return 0; + if (!bio_has_data(bio)) + return 1; + + if (!BIOVEC_PHYS_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt))) + return 0; + /* - * bio and nxt are contigous in memory, check if the queue allows + * bio and nxt are contiguous in memory; check if the queue allows * these two to be merged into one */ if (BIO_SEG_BOUNDARY(q, bio, nxt)) @@ -153,8 +157,9 @@ static int blk_hw_contig_segment(struct request_queue *q, struct bio *bio, blk_recount_segments(q, bio); if (!bio_flagged(nxt, BIO_SEG_VALID)) blk_recount_segments(q, nxt); - if (!BIOVEC_VIRT_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt)) || - BIOVEC_VIRT_OVERSIZE(bio->bi_hw_back_size + nxt->bi_hw_front_size)) + if (bio_has_data(bio) && + (!BIOVEC_VIRT_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt)) || + BIOVEC_VIRT_OVERSIZE(bio->bi_hw_back_size + nxt->bi_hw_front_size))) return 0; if (bio->bi_hw_back_size + nxt->bi_hw_front_size > q->max_segment_size) return 0; @@ -317,8 +322,9 @@ int ll_back_merge_fn(struct request_queue *q, struct request *req, if (!bio_flagged(bio, BIO_SEG_VALID)) blk_recount_segments(q, bio); len = req->biotail->bi_hw_back_size + bio->bi_hw_front_size; - if (BIOVEC_VIRT_MERGEABLE(__BVEC_END(req->biotail), __BVEC_START(bio)) - && !BIOVEC_VIRT_OVERSIZE(len)) { + if (!bio_has_data(bio) || + (BIOVEC_VIRT_MERGEABLE(__BVEC_END(req->biotail), __BVEC_START(bio)) + && !BIOVEC_VIRT_OVERSIZE(len))) { int mergeable = ll_new_mergeable(q, req, bio); if (mergeable) { @@ -356,8 +362,9 @@ int ll_front_merge_fn(struct request_queue *q, struct request *req, blk_recount_segments(q, bio); if (!bio_flagged(req->bio, BIO_SEG_VALID)) blk_recount_segments(q, req->bio); - if (BIOVEC_VIRT_MERGEABLE(__BVEC_END(bio), __BVEC_START(req->bio)) && - !BIOVEC_VIRT_OVERSIZE(len)) { + if (!bio_has_data(bio) || + (BIOVEC_VIRT_MERGEABLE(__BVEC_END(bio), __BVEC_START(req->bio)) && + !BIOVEC_VIRT_OVERSIZE(len))) { int mergeable = ll_new_mergeable(q, req, bio); if (mergeable) { diff --git a/block/elevator.c b/block/elevator.c index ed6f8f32d27..4f5127054e3 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -74,6 +74,12 @@ int elv_rq_merge_ok(struct request *rq, struct bio *bio) if (!rq_mergeable(rq)) return 0; + /* + * Don't merge file system requests and discard requests + */ + if (bio_discard(bio) != bio_discard(rq->bio)) + return 0; + /* * different data direction or already started, don't merge */ @@ -438,6 +444,8 @@ void elv_dispatch_sort(struct request_queue *q, struct request *rq) list_for_each_prev(entry, &q->queue_head) { struct request *pos = list_entry_rq(entry); + if (blk_discard_rq(rq) != blk_discard_rq(pos)) + break; if (rq_data_dir(rq) != rq_data_dir(pos)) break; if (pos->cmd_flags & stop_flags) @@ -607,7 +615,7 @@ void elv_insert(struct request_queue *q, struct request *rq, int where) break; case ELEVATOR_INSERT_SORT: - BUG_ON(!blk_fs_request(rq)); + BUG_ON(!blk_fs_request(rq) && !blk_discard_rq(rq)); rq->cmd_flags |= REQ_SORTED; q->nr_sorted++; if (rq_mergeable(rq)) { @@ -692,7 +700,7 @@ void __elv_add_request(struct request_queue *q, struct request *rq, int where, * this request is scheduling boundary, update * end_sector */ - if (blk_fs_request(rq)) { + if (blk_fs_request(rq) || blk_discard_rq(rq)) { q->end_sector = rq_end_sector(rq); q->boundary_rq = rq; } diff --git a/block/ioctl.c b/block/ioctl.c index 342298bb608..375c57922b0 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -161,7 +161,7 @@ static int blk_ioctl_discard(struct block_device *bdev, uint64_t start, bio->bi_size = len << 9; len = 0; } - submit_bio(WRITE_DISCARD, bio); + submit_bio(DISCARD_NOBARRIER, bio); wait_for_completion(&wait); diff --git a/include/linux/bio.h b/include/linux/bio.h index 1fdfc5621c8..33c3947d61e 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -188,8 +188,8 @@ struct bio { #define bio_failfast(bio) ((bio)->bi_rw & (1 << BIO_RW_FAILFAST)) #define bio_rw_ahead(bio) ((bio)->bi_rw & (1 << BIO_RW_AHEAD)) #define bio_rw_meta(bio) ((bio)->bi_rw & (1 << BIO_RW_META)) -#define bio_empty_barrier(bio) (bio_barrier(bio) && !bio_has_data(bio)) #define bio_discard(bio) ((bio)->bi_rw & (1 << BIO_RW_DISCARD)) +#define bio_empty_barrier(bio) (bio_barrier(bio) && !bio_has_data(bio) && !bio_discard(bio)) static inline unsigned int bio_cur_sectors(struct bio *bio) { diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 727886d25c4..e9eb35c9bf2 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -541,7 +541,7 @@ enum { #define blk_noretry_request(rq) ((rq)->cmd_flags & REQ_FAILFAST) #define blk_rq_started(rq) ((rq)->cmd_flags & REQ_STARTED) -#define blk_account_rq(rq) (blk_rq_started(rq) && blk_fs_request(rq)) +#define blk_account_rq(rq) (blk_rq_started(rq) && (blk_fs_request(rq) || blk_discard_rq(rq))) #define blk_pm_suspend_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND) #define blk_pm_resume_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_RESUME) @@ -598,7 +598,8 @@ static inline void blk_clear_queue_full(struct request_queue *q, int rw) #define RQ_NOMERGE_FLAGS \ (REQ_NOMERGE | REQ_STARTED | REQ_HARDBARRIER | REQ_SOFTBARRIER) #define rq_mergeable(rq) \ - (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && blk_fs_request((rq))) + (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \ + (blk_discard_rq(rq) || blk_fs_request((rq)))) /* * q->prep_rq_fn return values diff --git a/include/linux/fs.h b/include/linux/fs.h index 88358ca6af2..860689f541b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -87,7 +87,8 @@ extern int dir_notify_enable; #define WRITE_SYNC (WRITE | (1 << BIO_RW_SYNC)) #define SWRITE_SYNC (SWRITE | (1 << BIO_RW_SYNC)) #define WRITE_BARRIER (WRITE | (1 << BIO_RW_BARRIER)) -#define WRITE_DISCARD (WRITE | (1 << BIO_RW_DISCARD)) +#define DISCARD_NOBARRIER (1 << BIO_RW_DISCARD) +#define DISCARD_BARRIER ((1 << BIO_RW_DISCARD) | (1 << BIO_RW_BARRIER)) #define SEL_IN 1 #define SEL_OUT 2 -- cgit v1.2.3-70-g09d2 From b8b3e16cfe6435d961f6aaebcfd52a1ff2a988c5 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Fri, 15 Aug 2008 10:15:19 +0200 Subject: block: drop virtual merging accounting Remove virtual merge accounting. Signed-off-by: Mikulas Patocka Signed-off-by: Jens Axboe --- block/blk-merge.c | 79 ++++------------------------------------------------- fs/bio.c | 6 ++-- include/linux/bio.h | 15 ---------- 3 files changed, 8 insertions(+), 92 deletions(-) (limited to 'include/linux/bio.h') diff --git a/block/blk-merge.c b/block/blk-merge.c index 6cf8f0c70a5..2c2a2ee716e 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -66,7 +66,7 @@ void blk_recalc_rq_segments(struct request *rq) */ high = page_to_pfn(bv->bv_page) > q->bounce_pfn; if (high || highprv) - goto new_hw_segment; + goto new_segment; if (cluster) { if (seg_size + bv->bv_len > q->max_segment_size) goto new_segment; @@ -74,8 +74,6 @@ void blk_recalc_rq_segments(struct request *rq) goto new_segment; if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bv)) goto new_segment; - if (BIOVEC_VIRT_OVERSIZE(hw_seg_size + bv->bv_len)) - goto new_hw_segment; seg_size += bv->bv_len; hw_seg_size += bv->bv_len; @@ -83,17 +81,11 @@ void blk_recalc_rq_segments(struct request *rq) continue; } new_segment: - if (BIOVEC_VIRT_MERGEABLE(bvprv, bv) && - !BIOVEC_VIRT_OVERSIZE(hw_seg_size + bv->bv_len)) - hw_seg_size += bv->bv_len; - else { -new_hw_segment: - 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++; - } + 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 = bv->bv_len; + nr_hw_segs++; nr_phys_segs++; bvprv = bv; @@ -150,23 +142,6 @@ static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio, return 0; } -static int blk_hw_contig_segment(struct request_queue *q, struct bio *bio, - struct bio *nxt) -{ - if (!bio_flagged(bio, BIO_SEG_VALID)) - blk_recount_segments(q, bio); - if (!bio_flagged(nxt, BIO_SEG_VALID)) - blk_recount_segments(q, nxt); - if (bio_has_data(bio) && - (!BIOVEC_VIRT_MERGEABLE(__BVEC_END(bio), __BVEC_START(nxt)) || - BIOVEC_VIRT_OVERSIZE(bio->bi_hw_back_size + nxt->bi_hw_front_size))) - return 0; - if (bio->bi_hw_back_size + nxt->bi_hw_front_size > q->max_segment_size) - return 0; - - return 1; -} - /* * map a request to scatterlist, return number of sg entries setup. Caller * must make sure sg can hold rq->nr_phys_segments entries @@ -304,7 +279,6 @@ int ll_back_merge_fn(struct request_queue *q, struct request *req, struct bio *bio) { unsigned short max_sectors; - int len; if (unlikely(blk_pc_request(req))) max_sectors = q->max_hw_sectors; @@ -321,20 +295,6 @@ int ll_back_merge_fn(struct request_queue *q, struct request *req, blk_recount_segments(q, req->biotail); if (!bio_flagged(bio, BIO_SEG_VALID)) blk_recount_segments(q, bio); - len = req->biotail->bi_hw_back_size + bio->bi_hw_front_size; - if (!bio_has_data(bio) || - (BIOVEC_VIRT_MERGEABLE(__BVEC_END(req->biotail), __BVEC_START(bio)) - && !BIOVEC_VIRT_OVERSIZE(len))) { - int mergeable = ll_new_mergeable(q, req, bio); - - if (mergeable) { - if (req->nr_hw_segments == 1) - req->bio->bi_hw_front_size = len; - if (bio->bi_hw_segments == 1) - bio->bi_hw_back_size = len; - } - return mergeable; - } return ll_new_hw_segment(q, req, bio); } @@ -343,7 +303,6 @@ int ll_front_merge_fn(struct request_queue *q, struct request *req, struct bio *bio) { unsigned short max_sectors; - int len; if (unlikely(blk_pc_request(req))) max_sectors = q->max_hw_sectors; @@ -357,24 +316,10 @@ int ll_front_merge_fn(struct request_queue *q, struct request *req, q->last_merge = NULL; return 0; } - len = bio->bi_hw_back_size + req->bio->bi_hw_front_size; if (!bio_flagged(bio, BIO_SEG_VALID)) blk_recount_segments(q, bio); if (!bio_flagged(req->bio, BIO_SEG_VALID)) blk_recount_segments(q, req->bio); - if (!bio_has_data(bio) || - (BIOVEC_VIRT_MERGEABLE(__BVEC_END(bio), __BVEC_START(req->bio)) && - !BIOVEC_VIRT_OVERSIZE(len))) { - int mergeable = ll_new_mergeable(q, req, bio); - - if (mergeable) { - if (bio->bi_hw_segments == 1) - bio->bi_hw_front_size = len; - if (req->nr_hw_segments == 1) - req->biotail->bi_hw_back_size = len; - } - return mergeable; - } return ll_new_hw_segment(q, req, bio); } @@ -406,18 +351,6 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req, return 0; total_hw_segments = req->nr_hw_segments + next->nr_hw_segments; - if (blk_hw_contig_segment(q, req->biotail, next->bio)) { - int len = req->biotail->bi_hw_back_size + - next->bio->bi_hw_front_size; - /* - * propagate the combined length to the end of the requests - */ - if (req->nr_hw_segments == 1) - req->bio->bi_hw_front_size = len; - if (next->nr_hw_segments == 1) - next->biotail->bi_hw_back_size = len; - total_hw_segments--; - } if (total_hw_segments > q->max_hw_segments) return 0; diff --git a/fs/bio.c b/fs/bio.c index 3cba7ae34d7..4ac7c59d1c6 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -350,8 +350,7 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page */ while (bio->bi_phys_segments >= q->max_phys_segments - || bio->bi_hw_segments >= q->max_hw_segments - || BIOVEC_VIRT_OVERSIZE(bio->bi_size)) { + || bio->bi_hw_segments >= q->max_hw_segments) { if (retried_segments) return 0; @@ -395,8 +394,7 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page } /* If we may be able to merge these biovecs, force a recount */ - if (bio->bi_vcnt && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec) || - BIOVEC_VIRT_MERGEABLE(bvec-1, bvec))) + if (bio->bi_vcnt && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec))) bio->bi_flags &= ~(1 << BIO_SEG_VALID); bio->bi_vcnt++; diff --git a/include/linux/bio.h b/include/linux/bio.h index 33c3947d61e..894d16ce002 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -26,21 +26,8 @@ #ifdef CONFIG_BLOCK -/* Platforms may set this to teach the BIO layer about IOMMU hardware. */ #include -#if defined(BIO_VMERGE_MAX_SIZE) && defined(BIO_VMERGE_BOUNDARY) -#define BIOVEC_VIRT_START_SIZE(x) (bvec_to_phys(x) & (BIO_VMERGE_BOUNDARY - 1)) -#define BIOVEC_VIRT_OVERSIZE(x) ((x) > BIO_VMERGE_MAX_SIZE) -#else -#define BIOVEC_VIRT_START_SIZE(x) 0 -#define BIOVEC_VIRT_OVERSIZE(x) 0 -#endif - -#ifndef BIO_VMERGE_BOUNDARY -#define BIO_VMERGE_BOUNDARY 0 -#endif - #define BIO_DEBUG #ifdef BIO_DEBUG @@ -240,8 +227,6 @@ static inline void *bio_data(struct bio *bio) ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2))) #endif -#define BIOVEC_VIRT_MERGEABLE(vec1, vec2) \ - ((((bvec_to_phys((vec1)) + (vec1)->bv_len) | bvec_to_phys((vec2))) & (BIO_VMERGE_BOUNDARY - 1)) == 0) #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \ (((addr1) | (mask)) == (((addr2) - 1) | (mask))) #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \ -- cgit v1.2.3-70-g09d2 From 5df97b91b5d7ed426034fcc84cb6e7cf682b8838 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Fri, 15 Aug 2008 10:20:02 +0200 Subject: drop vmerge accounting Remove hw_segments field from struct bio and struct request. Without virtual merge accounting they have no purpose. Signed-off-by: Mikulas Patocka Signed-off-by: Jens Axboe --- block/blk-core.c | 1 - block/blk-merge.c | 31 ++++--------------------------- block/elevator.c | 2 -- drivers/md/raid1.c | 3 --- drivers/md/raid10.c | 3 --- fs/bio.c | 12 +----------- include/linux/bio.h | 16 +--------------- include/linux/blkdev.h | 7 ------- 8 files changed, 6 insertions(+), 69 deletions(-) (limited to 'include/linux/bio.h') diff --git a/block/blk-core.c b/block/blk-core.c index 1261516dd42..2616cdd049a 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -2026,7 +2026,6 @@ void blk_rq_bio_prep(struct request_queue *q, struct request *rq, if (bio_has_data(bio)) { rq->nr_phys_segments = bio_phys_segments(q, bio); - rq->nr_hw_segments = bio_hw_segments(q, bio); rq->buffer = bio_data(bio); } rq->current_nr_sectors = bio_cur_sectors(bio); diff --git a/block/blk-merge.c b/block/blk-merge.c index 2c2a2ee716e..d81d91419ff 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -41,12 +41,9 @@ void blk_recalc_rq_sectors(struct request *rq, int nsect) 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 seg_size; - int hw_seg_size; int cluster; struct req_iterator iter; int high, highprv = 1; @@ -56,8 +53,8 @@ void blk_recalc_rq_segments(struct request *rq) return; cluster = test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags); - hw_seg_size = seg_size = 0; - phys_size = hw_size = nr_phys_segs = nr_hw_segs = 0; + seg_size = 0; + phys_size = nr_phys_segs = 0; rq_for_each_segment(bv, rq, iter) { /* * the trick here is making sure that a high page is never @@ -76,30 +73,17 @@ void blk_recalc_rq_segments(struct request *rq) goto new_segment; seg_size += bv->bv_len; - hw_seg_size += bv->bv_len; bvprv = bv; continue; } new_segment: - 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 = bv->bv_len; - nr_hw_segs++; - nr_phys_segs++; bvprv = bv; seg_size = bv->bv_len; highprv = high; } - 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; } void blk_recount_segments(struct request_queue *q, struct bio *bio) @@ -112,7 +96,6 @@ void blk_recount_segments(struct request_queue *q, struct bio *bio) 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); @@ -255,10 +238,9 @@ static inline int ll_new_hw_segment(struct request_queue *q, struct request *req, struct bio *bio) { - int nr_hw_segs = bio_hw_segments(q, bio); int nr_phys_segs = bio_phys_segments(q, bio); - if (req->nr_hw_segments + nr_hw_segs > q->max_hw_segments + if (req->nr_phys_segments + nr_phys_segs > q->max_hw_segments || req->nr_phys_segments + nr_phys_segs > q->max_phys_segments) { req->cmd_flags |= REQ_NOMERGE; if (req == q->last_merge) @@ -270,7 +252,6 @@ static inline int ll_new_hw_segment(struct request_queue *q, * This will form the start of a new hw segment. Bump both * counters. */ - req->nr_hw_segments += nr_hw_segs; req->nr_phys_segments += nr_phys_segs; return 1; } @@ -328,7 +309,6 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req, struct request *next) { int total_phys_segments; - int total_hw_segments; /* * First check if the either of the requests are re-queued @@ -350,14 +330,11 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req, if (total_phys_segments > q->max_phys_segments) return 0; - total_hw_segments = req->nr_hw_segments + next->nr_hw_segments; - - if (total_hw_segments > q->max_hw_segments) + if (total_phys_segments > q->max_hw_segments) return 0; /* Merge is OK... */ req->nr_phys_segments = total_phys_segments; - req->nr_hw_segments = total_hw_segments; return 1; } diff --git a/block/elevator.c b/block/elevator.c index 4f5127054e3..269615e6dbf 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -790,7 +790,6 @@ struct request *elv_next_request(struct request_queue *q) * device can handle */ rq->nr_phys_segments++; - rq->nr_hw_segments++; } if (!q->prep_rq_fn) @@ -813,7 +812,6 @@ struct request *elv_next_request(struct request_queue *q) * so that we don't add it again */ --rq->nr_phys_segments; - --rq->nr_hw_segments; } rq = NULL; diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 03a5ab705c2..28a3869dcfd 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1302,9 +1302,6 @@ static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio) sbio->bi_size = r1_bio->sectors << 9; sbio->bi_idx = 0; sbio->bi_phys_segments = 0; - sbio->bi_hw_segments = 0; - sbio->bi_hw_front_size = 0; - sbio->bi_hw_back_size = 0; sbio->bi_flags &= ~(BIO_POOL_MASK - 1); sbio->bi_flags |= 1 << BIO_UPTODATE; sbio->bi_next = NULL; diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index e34cd0e6247..0f40688503e 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1345,9 +1345,6 @@ static void sync_request_write(mddev_t *mddev, r10bio_t *r10_bio) tbio->bi_size = r10_bio->sectors << 9; tbio->bi_idx = 0; tbio->bi_phys_segments = 0; - tbio->bi_hw_segments = 0; - tbio->bi_hw_front_size = 0; - tbio->bi_hw_back_size = 0; tbio->bi_flags &= ~(BIO_POOL_MASK - 1); tbio->bi_flags |= 1 << BIO_UPTODATE; tbio->bi_next = NULL; diff --git a/fs/bio.c b/fs/bio.c index 4ac7c59d1c6..bee4deca774 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -208,14 +208,6 @@ inline int bio_phys_segments(struct request_queue *q, struct bio *bio) return bio->bi_phys_segments; } -inline int bio_hw_segments(struct request_queue *q, struct bio *bio) -{ - if (unlikely(!bio_flagged(bio, BIO_SEG_VALID))) - blk_recount_segments(q, bio); - - return bio->bi_hw_segments; -} - /** * __bio_clone - clone a bio * @bio: destination bio @@ -350,7 +342,7 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page */ while (bio->bi_phys_segments >= q->max_phys_segments - || bio->bi_hw_segments >= q->max_hw_segments) { + || bio->bi_phys_segments >= q->max_hw_segments) { if (retried_segments) return 0; @@ -399,7 +391,6 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page bio->bi_vcnt++; bio->bi_phys_segments++; - bio->bi_hw_segments++; done: bio->bi_size += len; return len; @@ -1381,7 +1372,6 @@ EXPORT_SYMBOL(bio_init); EXPORT_SYMBOL(__bio_clone); EXPORT_SYMBOL(bio_clone); EXPORT_SYMBOL(bio_phys_segments); -EXPORT_SYMBOL(bio_hw_segments); EXPORT_SYMBOL(bio_add_page); EXPORT_SYMBOL(bio_add_pc_page); EXPORT_SYMBOL(bio_get_nr_vecs); diff --git a/include/linux/bio.h b/include/linux/bio.h index 894d16ce002..dfc3556d311 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -77,21 +77,8 @@ struct bio { */ unsigned short bi_phys_segments; - /* Number of segments after physical and DMA remapping - * hardware coalescing is performed. - */ - unsigned short bi_hw_segments; - unsigned int bi_size; /* residual I/O count */ - /* - * To keep track of the max hw size, we account for the - * sizes of the first and last virtually mergeable segments - * in this bio - */ - unsigned int bi_hw_front_size; - unsigned int bi_hw_back_size; - unsigned int bi_max_vecs; /* max bvl_vecs we can hold */ struct bio_vec *bi_io_vec; /* the actual vec list */ @@ -113,7 +100,7 @@ struct bio { #define BIO_UPTODATE 0 /* ok after I/O completion */ #define BIO_RW_BLOCK 1 /* RW_AHEAD set, and read/write would block */ #define BIO_EOF 2 /* out-out-bounds error */ -#define BIO_SEG_VALID 3 /* nr_hw_seg valid */ +#define BIO_SEG_VALID 3 /* bi_phys_segments valid */ #define BIO_CLONED 4 /* doesn't own data */ #define BIO_BOUNCED 5 /* bio is a bounce bio */ #define BIO_USER_MAPPED 6 /* contains user pages */ @@ -324,7 +311,6 @@ extern void bio_free(struct bio *, struct bio_set *); extern void bio_endio(struct bio *, int); struct request_queue; extern int bio_phys_segments(struct request_queue *, struct bio *); -extern int bio_hw_segments(struct request_queue *, struct bio *); extern void __bio_clone(struct bio *, struct bio *); extern struct bio *bio_clone(struct bio *, gfp_t); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 490ce458b03..1adb03827bd 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -189,13 +189,6 @@ struct request { */ unsigned short nr_phys_segments; - /* Number of scatter-gather addr+len pairs after - * physical and DMA remapping hardware coalescing is performed. - * This is the number of scatter-gather entries the driver - * will actually have to deal with after DMA mapping is done. - */ - unsigned short nr_hw_segments; - unsigned short ioprio; void *special; -- cgit v1.2.3-70-g09d2 From 5b99c2ffa980528a197f26c7d876cceeccce8dd5 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 15 Aug 2008 10:56:11 +0200 Subject: block: make bi_phys_segments an unsigned int instead of short raid5 can overflow with more than 255 stripes, and we can increase it to an int for free on both 32 and 64-bit archs due to the padding. Signed-off-by: Jens Axboe --- drivers/md/raid5.c | 12 ++++++------ include/linux/bio.h | 2 +- 2 files changed, 7 insertions(+), 7 deletions(-) (limited to 'include/linux/bio.h') diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 05b22925cce..37e546528f9 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -102,17 +102,17 @@ const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(256))); #endif /* - * We maintain a biased count of active stripes in the bottom 8 bits of - * bi_phys_segments, and a count of processed stripes in the upper 8 bits + * We maintain a biased count of active stripes in the bottom 16 bits of + * bi_phys_segments, and a count of processed stripes in the upper 16 bits */ static inline int raid5_bi_phys_segments(struct bio *bio) { - return bio->bi_phys_segments & 0xff; + return bio->bi_phys_segments & 0xffff; } static inline int raid5_bi_hw_segments(struct bio *bio) { - return (bio->bi_phys_segments >> 8) & 0xff; + return (bio->bi_phys_segments >> 16) & 0xffff; } static inline int raid5_dec_bi_phys_segments(struct bio *bio) @@ -126,13 +126,13 @@ static inline int raid5_dec_bi_hw_segments(struct bio *bio) unsigned short val = raid5_bi_hw_segments(bio); --val; - bio->bi_phys_segments = (val << 8) | raid5_bi_phys_segments(bio); + bio->bi_phys_segments = (val << 16) | raid5_bi_phys_segments(bio); return val; } static inline void raid5_set_bi_hw_segments(struct bio *bio, unsigned int cnt) { - bio->bi_phys_segments = raid5_bi_phys_segments(bio) || (cnt << 8); + bio->bi_phys_segments = raid5_bi_phys_segments(bio) || (cnt << 16); } static inline int raid6_next_disk(int disk, int raid_disks) diff --git a/include/linux/bio.h b/include/linux/bio.h index dfc3556d311..2c0c09034fd 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -75,7 +75,7 @@ struct bio { /* Number of segments in this BIO after * physical address coalescing is performed. */ - unsigned short bi_phys_segments; + unsigned int bi_phys_segments; unsigned int bi_size; /* residual I/O count */ -- cgit v1.2.3-70-g09d2 From c7c22e4d5c1fdebfac4dba76de7d0338c2b0d832 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Sat, 13 Sep 2008 20:26:01 +0200 Subject: block: add support for IO CPU affinity This patch adds support for controlling the IO completion CPU of either all requests on a queue, or on a per-request basis. We export a sysfs variable (rq_affinity) which, if set, migrates completions of requests to the CPU that originally submitted it. A bio helper (bio_set_completion_cpu()) is also added, so that queuers can ask for completion on that specific CPU. In testing, this has been show to cut the system time by as much as 20-40% on synthetic workloads where CPU affinity is desired. This requires a little help from the architecture, so it'll only work as designed for archs that are using the new generic smp helper infrastructure. Signed-off-by: Jens Axboe --- block/blk-core.c | 46 ++++++++--------- block/blk-settings.c | 2 +- block/blk-softirq.c | 126 +++++++++++++++++++++++++++++++++++------------ block/blk-sysfs.c | 31 ++++++++++++ block/blk.h | 12 +++++ fs/bio.c | 1 + include/linux/bio.h | 11 +++++ include/linux/blkdev.h | 5 +- include/linux/elevator.h | 8 +-- 9 files changed, 182 insertions(+), 60 deletions(-) (limited to 'include/linux/bio.h') diff --git a/block/blk-core.c b/block/blk-core.c index 9c6f818d0c3..5484838f46e 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -110,7 +110,7 @@ void blk_rq_init(struct request_queue *q, struct request *rq) memset(rq, 0, sizeof(*rq)); INIT_LIST_HEAD(&rq->queuelist); - INIT_LIST_HEAD(&rq->donelist); + rq->cpu = -1; rq->q = q; rq->sector = rq->hard_sector = (sector_t) -1; INIT_HLIST_NODE(&rq->hash); @@ -322,6 +322,21 @@ void blk_unplug(struct request_queue *q) } EXPORT_SYMBOL(blk_unplug); +static void blk_invoke_request_fn(struct request_queue *q) +{ + /* + * one level of recursion is ok and is much faster than kicking + * the unplug handling + */ + if (!queue_flag_test_and_set(QUEUE_FLAG_REENTER, q)) { + q->request_fn(q); + queue_flag_clear(QUEUE_FLAG_REENTER, q); + } else { + queue_flag_set(QUEUE_FLAG_PLUGGED, q); + kblockd_schedule_work(q, &q->unplug_work); + } +} + /** * blk_start_queue - restart a previously stopped queue * @q: The &struct request_queue in question @@ -336,18 +351,7 @@ void blk_start_queue(struct request_queue *q) WARN_ON(!irqs_disabled()); queue_flag_clear(QUEUE_FLAG_STOPPED, q); - - /* - * one level of recursion is ok and is much faster than kicking - * the unplug handling - */ - if (!queue_flag_test_and_set(QUEUE_FLAG_REENTER, q)) { - q->request_fn(q); - queue_flag_clear(QUEUE_FLAG_REENTER, q); - } else { - blk_plug_device(q); - kblockd_schedule_work(q, &q->unplug_work); - } + blk_invoke_request_fn(q); } EXPORT_SYMBOL(blk_start_queue); @@ -405,15 +409,8 @@ void __blk_run_queue(struct request_queue *q) * Only recurse once to avoid overrunning the stack, let the unplug * handling reinvoke the handler shortly if we already got there. */ - if (!elv_queue_empty(q)) { - if (!queue_flag_test_and_set(QUEUE_FLAG_REENTER, q)) { - q->request_fn(q); - queue_flag_clear(QUEUE_FLAG_REENTER, q); - } else { - blk_plug_device(q); - kblockd_schedule_work(q, &q->unplug_work); - } - } + if (!elv_queue_empty(q)) + blk_invoke_request_fn(q); } EXPORT_SYMBOL(__blk_run_queue); @@ -1056,6 +1053,7 @@ EXPORT_SYMBOL(blk_put_request); void init_request_from_bio(struct request *req, struct bio *bio) { + req->cpu = bio->bi_comp_cpu; req->cmd_type = REQ_TYPE_FS; /* @@ -1198,13 +1196,15 @@ get_rq: init_request_from_bio(req, bio); spin_lock_irq(q->queue_lock); + if (test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags) || + bio_flagged(bio, BIO_CPU_AFFINE)) + req->cpu = blk_cpu_to_group(smp_processor_id()); if (elv_queue_empty(q)) blk_plug_device(q); add_request(q, req); out: if (sync) __generic_unplug_device(q); - spin_unlock_irq(q->queue_lock); return 0; diff --git a/block/blk-settings.c b/block/blk-settings.c index d70692badcd..a60e959a12c 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -443,7 +443,7 @@ void blk_queue_update_dma_alignment(struct request_queue *q, int mask) } EXPORT_SYMBOL(blk_queue_update_dma_alignment); -static int __init blk_settings_init(void) +int __init blk_settings_init(void) { blk_max_low_pfn = max_low_pfn - 1; blk_max_pfn = max_pfn - 1; diff --git a/block/blk-softirq.c b/block/blk-softirq.c index 9e1c43bff66..3a1af551191 100644 --- a/block/blk-softirq.c +++ b/block/blk-softirq.c @@ -13,6 +13,70 @@ static DEFINE_PER_CPU(struct list_head, blk_cpu_done); +/* + * Softirq action handler - move entries to local list and loop over them + * while passing them to the queue registered handler. + */ +static void blk_done_softirq(struct softirq_action *h) +{ + struct list_head *cpu_list, local_list; + + local_irq_disable(); + cpu_list = &__get_cpu_var(blk_cpu_done); + list_replace_init(cpu_list, &local_list); + local_irq_enable(); + + while (!list_empty(&local_list)) { + struct request *rq; + + rq = list_entry(local_list.next, struct request, csd.list); + list_del_init(&rq->csd.list); + rq->q->softirq_done_fn(rq); + } +} + +#if defined(CONFIG_SMP) && defined(CONFIG_USE_GENERIC_SMP_HELPERS) +static void trigger_softirq(void *data) +{ + struct request *rq = data; + unsigned long flags; + struct list_head *list; + + local_irq_save(flags); + list = &__get_cpu_var(blk_cpu_done); + list_add_tail(&rq->csd.list, list); + + if (list->next == &rq->csd.list) + raise_softirq_irqoff(BLOCK_SOFTIRQ); + + local_irq_restore(flags); +} + +/* + * Setup and invoke a run of 'trigger_softirq' on the given cpu. + */ +static int raise_blk_irq(int cpu, struct request *rq) +{ + if (cpu_online(cpu)) { + struct call_single_data *data = &rq->csd; + + data->func = trigger_softirq; + data->info = rq; + data->flags = 0; + + __smp_call_function_single(cpu, data); + return 0; + } + + return 1; +} +#else /* CONFIG_SMP && CONFIG_USE_GENERIC_SMP_HELPERS */ +static int raise_blk_irq(int cpu, struct request *rq) +{ + return 1; +} +#endif + static int __cpuinit blk_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) { @@ -33,33 +97,10 @@ static int __cpuinit blk_cpu_notify(struct notifier_block *self, return NOTIFY_OK; } - -static struct notifier_block blk_cpu_notifier __cpuinitdata = { +static struct notifier_block __cpuinitdata blk_cpu_notifier = { .notifier_call = blk_cpu_notify, }; -/* - * splice the completion data to a local structure and hand off to - * process_completion_queue() to complete the requests - */ -static void blk_done_softirq(struct softirq_action *h) -{ - struct list_head *cpu_list, local_list; - - local_irq_disable(); - cpu_list = &__get_cpu_var(blk_cpu_done); - list_replace_init(cpu_list, &local_list); - local_irq_enable(); - - while (!list_empty(&local_list)) { - struct request *rq; - - rq = list_entry(local_list.next, struct request, donelist); - list_del_init(&rq->donelist); - rq->q->softirq_done_fn(rq); - } -} - /** * blk_complete_request - end I/O on a request * @req: the request being processed @@ -71,25 +112,48 @@ static void blk_done_softirq(struct softirq_action *h) * through a softirq handler. The user must have registered a completion * callback through blk_queue_softirq_done(). **/ - void blk_complete_request(struct request *req) { - struct list_head *cpu_list; + struct request_queue *q = req->q; unsigned long flags; + int ccpu, cpu, group_cpu; - BUG_ON(!req->q->softirq_done_fn); + BUG_ON(!q->softirq_done_fn); local_irq_save(flags); + cpu = smp_processor_id(); + group_cpu = blk_cpu_to_group(cpu); - cpu_list = &__get_cpu_var(blk_cpu_done); - list_add_tail(&req->donelist, cpu_list); - raise_softirq_irqoff(BLOCK_SOFTIRQ); + /* + * Select completion CPU + */ + if (test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags) && req->cpu != -1) + ccpu = req->cpu; + else + ccpu = cpu; + + if (ccpu == cpu || ccpu == group_cpu) { + struct list_head *list; +do_local: + list = &__get_cpu_var(blk_cpu_done); + list_add_tail(&req->csd.list, list); + + /* + * if the list only contains our just added request, + * signal a raise of the softirq. If there are already + * entries there, someone already raised the irq but it + * hasn't run yet. + */ + if (list->next == &req->csd.list) + raise_softirq_irqoff(BLOCK_SOFTIRQ); + } else if (raise_blk_irq(ccpu, req)) + goto do_local; local_irq_restore(flags); } EXPORT_SYMBOL(blk_complete_request); -int __init blk_softirq_init(void) +__init int blk_softirq_init(void) { int i; diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index b9a6ed16664..21e275d7eed 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -156,6 +156,30 @@ static ssize_t queue_nomerges_store(struct request_queue *q, const char *page, return ret; } +static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page) +{ + unsigned int set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags); + + return queue_var_show(set != 0, page); +} + +static ssize_t +queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count) +{ + ssize_t ret = -EINVAL; +#if defined(CONFIG_USE_GENERIC_SMP_HELPERS) + unsigned long val; + + ret = queue_var_store(&val, page, count); + spin_lock_irq(q->queue_lock); + if (val) + queue_flag_set(QUEUE_FLAG_SAME_COMP, q); + else + queue_flag_clear(QUEUE_FLAG_SAME_COMP, q); + spin_unlock_irq(q->queue_lock); +#endif + return ret; +} static struct queue_sysfs_entry queue_requests_entry = { .attr = {.name = "nr_requests", .mode = S_IRUGO | S_IWUSR }, @@ -197,6 +221,12 @@ static struct queue_sysfs_entry queue_nomerges_entry = { .store = queue_nomerges_store, }; +static struct queue_sysfs_entry queue_rq_affinity_entry = { + .attr = {.name = "rq_affinity", .mode = S_IRUGO | S_IWUSR }, + .show = queue_rq_affinity_show, + .store = queue_rq_affinity_store, +}; + static struct attribute *default_attrs[] = { &queue_requests_entry.attr, &queue_ra_entry.attr, @@ -205,6 +235,7 @@ static struct attribute *default_attrs[] = { &queue_iosched_entry.attr, &queue_hw_sector_size_entry.attr, &queue_nomerges_entry.attr, + &queue_rq_affinity_entry.attr, NULL, }; diff --git a/block/blk.h b/block/blk.h index c79f30e1df5..de74254cb91 100644 --- a/block/blk.h +++ b/block/blk.h @@ -59,4 +59,16 @@ static inline int queue_congestion_off_threshold(struct request_queue *q) #endif /* BLK_DEV_INTEGRITY */ +static inline int blk_cpu_to_group(int cpu) +{ +#ifdef CONFIG_SCHED_MC + cpumask_t mask = cpu_coregroup_map(cpu); + return first_cpu(mask); +#elif defined(CONFIG_SCHED_SMT) + return first_cpu(per_cpu(cpu_sibling_map, cpu)); +#else + return cpu; +#endif +} + #endif diff --git a/fs/bio.c b/fs/bio.c index bee4deca774..6a637b5c24b 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -111,6 +111,7 @@ void bio_init(struct bio *bio) { memset(bio, 0, sizeof(*bio)); bio->bi_flags = 1 << BIO_UPTODATE; + bio->bi_comp_cpu = -1; atomic_set(&bio->bi_cnt, 1); } diff --git a/include/linux/bio.h b/include/linux/bio.h index 2c0c09034fd..13aba20edb2 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -81,6 +81,8 @@ struct bio { unsigned int bi_max_vecs; /* max bvl_vecs we can hold */ + unsigned int bi_comp_cpu; /* completion CPU */ + struct bio_vec *bi_io_vec; /* the actual vec list */ bio_end_io_t *bi_end_io; @@ -105,6 +107,7 @@ struct bio { #define BIO_BOUNCED 5 /* bio is a bounce bio */ #define BIO_USER_MAPPED 6 /* contains user pages */ #define BIO_EOPNOTSUPP 7 /* not supported */ +#define BIO_CPU_AFFINE 8 /* complete bio on same CPU as submitted */ #define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag))) /* @@ -342,6 +345,14 @@ void zero_fill_bio(struct bio *bio); extern struct bio_vec *bvec_alloc_bs(gfp_t, int, unsigned long *, struct bio_set *); extern unsigned int bvec_nr_vecs(unsigned short idx); +/* + * Allow queuer to specify a completion CPU for this bio + */ +static inline void bio_set_completion_cpu(struct bio *bio, unsigned int cpu) +{ + bio->bi_comp_cpu = cpu; +} + /* * bio_set is used to allow other portions of the IO system to * allocate their own private memory pools for bio and iovec structures. diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 10aa46c8f17..93204bf7b29 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -17,6 +17,7 @@ #include #include #include +#include #include @@ -139,7 +140,8 @@ enum rq_flag_bits { */ struct request { struct list_head queuelist; - struct list_head donelist; + struct call_single_data csd; + int cpu; struct request_queue *q; @@ -420,6 +422,7 @@ struct request_queue #define QUEUE_FLAG_ELVSWITCH 8 /* don't use elevator, just do FIFO */ #define QUEUE_FLAG_BIDI 9 /* queue supports bidi requests */ #define QUEUE_FLAG_NOMERGES 10 /* disable merge attempts */ +#define QUEUE_FLAG_SAME_COMP 11 /* force complete on same CPU */ static inline int queue_is_locked(struct request_queue *q) { diff --git a/include/linux/elevator.h b/include/linux/elevator.h index 639624b55fb..bb791c311a5 100644 --- a/include/linux/elevator.h +++ b/include/linux/elevator.h @@ -173,15 +173,15 @@ enum { #define rb_entry_rq(node) rb_entry((node), struct request, rb_node) /* - * Hack to reuse the donelist list_head as the fifo time holder while + * Hack to reuse the csd.list list_head as the fifo time holder while * the request is in the io scheduler. Saves an unsigned long in rq. */ -#define rq_fifo_time(rq) ((unsigned long) (rq)->donelist.next) -#define rq_set_fifo_time(rq,exp) ((rq)->donelist.next = (void *) (exp)) +#define rq_fifo_time(rq) ((unsigned long) (rq)->csd.list.next) +#define rq_set_fifo_time(rq,exp) ((rq)->csd.list.next = (void *) (exp)) #define rq_entry_fifo(ptr) list_entry((ptr), struct request, queuelist) #define rq_fifo_clear(rq) do { \ list_del_init(&(rq)->queuelist); \ - INIT_LIST_HEAD(&(rq)->donelist); \ + INIT_LIST_HEAD(&(rq)->csd.list); \ } while (0) /* -- cgit v1.2.3-70-g09d2 From a3bce90edd8f6cafe3f63b1a943800792e830178 Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Thu, 28 Aug 2008 16:17:05 +0900 Subject: block: add gfp_mask argument to blk_rq_map_user and blk_rq_map_user_iov Currently, blk_rq_map_user and blk_rq_map_user_iov always do GFP_KERNEL allocation. This adds gfp_mask argument to blk_rq_map_user and blk_rq_map_user_iov so sg can use it (sg always does GFP_ATOMIC allocation). Signed-off-by: FUJITA Tomonori Signed-off-by: Douglas Gilbert Cc: Mike Christie Cc: James Bottomley Signed-off-by: Jens Axboe --- block/blk-map.c | 20 ++++++++++++-------- block/bsg.c | 5 +++-- block/scsi_ioctl.c | 5 +++-- drivers/cdrom/cdrom.c | 2 +- drivers/scsi/scsi_tgt_lib.c | 2 +- fs/bio.c | 33 +++++++++++++++++++-------------- include/linux/bio.h | 9 +++++---- include/linux/blkdev.h | 5 +++-- 8 files changed, 47 insertions(+), 34 deletions(-) (limited to 'include/linux/bio.h') diff --git a/block/blk-map.c b/block/blk-map.c index ea1bf53929e..ac21b7397e1 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -41,7 +41,8 @@ static int __blk_rq_unmap_user(struct bio *bio) } static int __blk_rq_map_user(struct request_queue *q, struct request *rq, - void __user *ubuf, unsigned int len) + void __user *ubuf, unsigned int len, + gfp_t gfp_mask) { unsigned long uaddr; unsigned int alignment; @@ -57,9 +58,9 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq, uaddr = (unsigned long) ubuf; alignment = queue_dma_alignment(q) | q->dma_pad_mask; if (!(uaddr & alignment) && !(len & alignment)) - bio = bio_map_user(q, NULL, uaddr, len, reading); + bio = bio_map_user(q, NULL, uaddr, len, reading, gfp_mask); else - bio = bio_copy_user(q, uaddr, len, reading); + bio = bio_copy_user(q, uaddr, len, reading, gfp_mask); if (IS_ERR(bio)) return PTR_ERR(bio); @@ -90,6 +91,7 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq, * @rq: request structure to fill * @ubuf: the user buffer * @len: length of user data + * @gfp_mask: memory allocation flags * * Description: * Data will be mapped directly for zero copy I/O, if possible. Otherwise @@ -105,7 +107,7 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq, * unmapping. */ int blk_rq_map_user(struct request_queue *q, struct request *rq, - void __user *ubuf, unsigned long len) + void __user *ubuf, unsigned long len, gfp_t gfp_mask) { unsigned long bytes_read = 0; struct bio *bio = NULL; @@ -132,7 +134,7 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq, if (end - start > BIO_MAX_PAGES) map_len -= PAGE_SIZE; - ret = __blk_rq_map_user(q, rq, ubuf, map_len); + ret = __blk_rq_map_user(q, rq, ubuf, map_len, gfp_mask); if (ret < 0) goto unmap_rq; if (!bio) @@ -160,6 +162,7 @@ EXPORT_SYMBOL(blk_rq_map_user); * @iov: pointer to the iovec * @iov_count: number of elements in the iovec * @len: I/O byte count + * @gfp_mask: memory allocation flags * * Description: * Data will be mapped directly for zero copy I/O, if possible. Otherwise @@ -175,7 +178,8 @@ EXPORT_SYMBOL(blk_rq_map_user); * unmapping. */ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, - struct sg_iovec *iov, int iov_count, unsigned int len) + struct sg_iovec *iov, int iov_count, unsigned int len, + gfp_t gfp_mask) { struct bio *bio; int i, read = rq_data_dir(rq) == READ; @@ -194,9 +198,9 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, } if (unaligned || (q->dma_pad_mask & len)) - bio = bio_copy_user_iov(q, iov, iov_count, read); + bio = bio_copy_user_iov(q, iov, iov_count, read, gfp_mask); else - bio = bio_map_user_iov(q, NULL, iov, iov_count, read); + bio = bio_map_user_iov(q, NULL, iov, iov_count, read, gfp_mask); if (IS_ERR(bio)) return PTR_ERR(bio); diff --git a/block/bsg.c b/block/bsg.c index 0aae8d7ba99..e7a142e9916 100644 --- a/block/bsg.c +++ b/block/bsg.c @@ -283,7 +283,8 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, int has_write_perm) next_rq->cmd_type = rq->cmd_type; dxferp = (void*)(unsigned long)hdr->din_xferp; - ret = blk_rq_map_user(q, next_rq, dxferp, hdr->din_xfer_len); + ret = blk_rq_map_user(q, next_rq, dxferp, hdr->din_xfer_len, + GFP_KERNEL); if (ret) goto out; } @@ -298,7 +299,7 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, int has_write_perm) dxfer_len = 0; if (dxfer_len) { - ret = blk_rq_map_user(q, rq, dxferp, dxfer_len); + ret = blk_rq_map_user(q, rq, dxferp, dxfer_len, GFP_KERNEL); if (ret) goto out; } diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c index 3aab80a4c48..f49d6a11a69 100644 --- a/block/scsi_ioctl.c +++ b/block/scsi_ioctl.c @@ -315,10 +315,11 @@ static int sg_io(struct file *file, struct request_queue *q, } ret = blk_rq_map_user_iov(q, rq, iov, hdr->iovec_count, - hdr->dxfer_len); + hdr->dxfer_len, GFP_KERNEL); kfree(iov); } else if (hdr->dxfer_len) - ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len); + ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len, + GFP_KERNEL); if (ret) goto out; diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c index 74031de517e..e861d24a6d3 100644 --- a/drivers/cdrom/cdrom.c +++ b/drivers/cdrom/cdrom.c @@ -2097,7 +2097,7 @@ static int cdrom_read_cdda_bpc(struct cdrom_device_info *cdi, __u8 __user *ubuf, len = nr * CD_FRAMESIZE_RAW; - ret = blk_rq_map_user(q, rq, ubuf, len); + ret = blk_rq_map_user(q, rq, ubuf, len, GFP_KERNEL); if (ret) break; diff --git a/drivers/scsi/scsi_tgt_lib.c b/drivers/scsi/scsi_tgt_lib.c index 257e097c39a..2a4fd820d61 100644 --- a/drivers/scsi/scsi_tgt_lib.c +++ b/drivers/scsi/scsi_tgt_lib.c @@ -362,7 +362,7 @@ static int scsi_map_user_pages(struct scsi_tgt_cmd *tcmd, struct scsi_cmnd *cmd, int err; dprintk("%lx %u\n", uaddr, len); - err = blk_rq_map_user(q, rq, (void *)uaddr, len); + err = blk_rq_map_user(q, rq, (void *)uaddr, len, GFP_KERNEL); if (err) { /* * TODO: need to fixup sg_tablesize, max_segment_size, diff --git a/fs/bio.c b/fs/bio.c index 6a637b5c24b..3d2e9ad2472 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -558,13 +558,14 @@ int bio_uncopy_user(struct bio *bio) * @iov: the iovec. * @iov_count: number of elements in the iovec * @write_to_vm: bool indicating writing to pages or not + * @gfp_mask: memory allocation flags * * Prepares and returns a bio for indirect user io, bouncing data * to/from kernel pages as necessary. Must be paired with * call bio_uncopy_user() on io completion. */ struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov, - int iov_count, int write_to_vm) + int iov_count, int write_to_vm, gfp_t gfp_mask) { struct bio_map_data *bmd; struct bio_vec *bvec; @@ -587,12 +588,12 @@ struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov, len += iov[i].iov_len; } - bmd = bio_alloc_map_data(nr_pages, iov_count, GFP_KERNEL); + bmd = bio_alloc_map_data(nr_pages, iov_count, gfp_mask); if (!bmd) return ERR_PTR(-ENOMEM); ret = -ENOMEM; - bio = bio_alloc(GFP_KERNEL, nr_pages); + bio = bio_alloc(gfp_mask, nr_pages); if (!bio) goto out_bmd; @@ -605,7 +606,7 @@ struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov, if (bytes > len) bytes = len; - page = alloc_page(q->bounce_gfp | GFP_KERNEL); + page = alloc_page(q->bounce_gfp | gfp_mask); if (!page) { ret = -ENOMEM; break; @@ -647,26 +648,27 @@ out_bmd: * @uaddr: start of user address * @len: length in bytes * @write_to_vm: bool indicating writing to pages or not + * @gfp_mask: memory allocation flags * * Prepares and returns a bio for indirect user io, bouncing data * to/from kernel pages as necessary. Must be paired with * call bio_uncopy_user() on io completion. */ struct bio *bio_copy_user(struct request_queue *q, unsigned long uaddr, - unsigned int len, int write_to_vm) + unsigned int len, int write_to_vm, gfp_t gfp_mask) { struct sg_iovec iov; iov.iov_base = (void __user *)uaddr; iov.iov_len = len; - return bio_copy_user_iov(q, &iov, 1, write_to_vm); + return bio_copy_user_iov(q, &iov, 1, write_to_vm, gfp_mask); } static struct bio *__bio_map_user_iov(struct request_queue *q, struct block_device *bdev, struct sg_iovec *iov, int iov_count, - int write_to_vm) + int write_to_vm, gfp_t gfp_mask) { int i, j; int nr_pages = 0; @@ -692,12 +694,12 @@ static struct bio *__bio_map_user_iov(struct request_queue *q, if (!nr_pages) return ERR_PTR(-EINVAL); - bio = bio_alloc(GFP_KERNEL, nr_pages); + bio = bio_alloc(gfp_mask, nr_pages); if (!bio) return ERR_PTR(-ENOMEM); ret = -ENOMEM; - pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL); + pages = kcalloc(nr_pages, sizeof(struct page *), gfp_mask); if (!pages) goto out; @@ -776,19 +778,21 @@ static struct bio *__bio_map_user_iov(struct request_queue *q, * @uaddr: start of user address * @len: length in bytes * @write_to_vm: bool indicating writing to pages or not + * @gfp_mask: memory allocation flags * * Map the user space address into a bio suitable for io to a block * device. Returns an error pointer in case of error. */ struct bio *bio_map_user(struct request_queue *q, struct block_device *bdev, - unsigned long uaddr, unsigned int len, int write_to_vm) + unsigned long uaddr, unsigned int len, int write_to_vm, + gfp_t gfp_mask) { struct sg_iovec iov; iov.iov_base = (void __user *)uaddr; iov.iov_len = len; - return bio_map_user_iov(q, bdev, &iov, 1, write_to_vm); + return bio_map_user_iov(q, bdev, &iov, 1, write_to_vm, gfp_mask); } /** @@ -798,18 +802,19 @@ struct bio *bio_map_user(struct request_queue *q, struct block_device *bdev, * @iov: the iovec. * @iov_count: number of elements in the iovec * @write_to_vm: bool indicating writing to pages or not + * @gfp_mask: memory allocation flags * * Map the user space address into a bio suitable for io to a block * device. Returns an error pointer in case of error. */ struct bio *bio_map_user_iov(struct request_queue *q, struct block_device *bdev, struct sg_iovec *iov, int iov_count, - int write_to_vm) + int write_to_vm, gfp_t gfp_mask) { struct bio *bio; - bio = __bio_map_user_iov(q, bdev, iov, iov_count, write_to_vm); - + bio = __bio_map_user_iov(q, bdev, iov, iov_count, write_to_vm, + gfp_mask); if (IS_ERR(bio)) return bio; diff --git a/include/linux/bio.h b/include/linux/bio.h index 13aba20edb2..200b185c3e8 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -325,11 +325,11 @@ extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, unsigned int, unsigned int); extern int bio_get_nr_vecs(struct block_device *); extern struct bio *bio_map_user(struct request_queue *, struct block_device *, - unsigned long, unsigned int, int); + unsigned long, unsigned int, int, gfp_t); struct sg_iovec; extern struct bio *bio_map_user_iov(struct request_queue *, struct block_device *, - struct sg_iovec *, int, int); + struct sg_iovec *, int, int, gfp_t); extern void bio_unmap_user(struct bio *); extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int, gfp_t); @@ -337,9 +337,10 @@ extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int, gfp_t, int); extern void bio_set_pages_dirty(struct bio *bio); extern void bio_check_pages_dirty(struct bio *bio); -extern struct bio *bio_copy_user(struct request_queue *, unsigned long, unsigned int, int); +extern struct bio *bio_copy_user(struct request_queue *, unsigned long, + unsigned int, int, gfp_t); extern struct bio *bio_copy_user_iov(struct request_queue *, struct sg_iovec *, - int, int); + int, int, gfp_t); extern int bio_uncopy_user(struct bio *); void zero_fill_bio(struct bio *bio); extern struct bio_vec *bvec_alloc_bs(gfp_t, int, unsigned long *, struct bio_set *); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 12df8efeef1..00e388d0e22 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -710,11 +710,12 @@ extern void __blk_stop_queue(struct request_queue *q); extern void __blk_run_queue(struct request_queue *); extern void blk_run_queue(struct request_queue *); extern void blk_start_queueing(struct request_queue *); -extern int blk_rq_map_user(struct request_queue *, struct request *, void __user *, unsigned long); +extern int blk_rq_map_user(struct request_queue *, struct request *, + void __user *, unsigned long, gfp_t); extern int blk_rq_unmap_user(struct bio *); extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); extern int blk_rq_map_user_iov(struct request_queue *, struct request *, - struct sg_iovec *, int, unsigned int); + struct sg_iovec *, int, unsigned int, gfp_t); extern int blk_execute_rq(struct request_queue *, struct gendisk *, struct request *, int); extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, -- cgit v1.2.3-70-g09d2 From 152e283fdfea0cd11e297d982378b55937842dde Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Thu, 28 Aug 2008 16:17:06 +0900 Subject: block: introduce struct rq_map_data to use reserved pages This patch introduces struct rq_map_data to enable bio_copy_use_iov() use reserved pages. Currently, bio_copy_user_iov allocates bounce pages but drivers/scsi/sg.c wants to allocate pages by itself and use them. struct rq_map_data can be used to pass allocated pages to bio_copy_user_iov. The current users of bio_copy_user_iov simply passes NULL (they don't want to use pre-allocated pages). Signed-off-by: FUJITA Tomonori Cc: Jens Axboe Cc: Douglas Gilbert Cc: Mike Christie Cc: James Bottomley Signed-off-by: Jens Axboe --- block/blk-map.c | 26 ++++++++++++-------- block/bsg.c | 7 +++--- block/scsi_ioctl.c | 4 ++-- drivers/cdrom/cdrom.c | 2 +- drivers/scsi/scsi_tgt_lib.c | 2 +- fs/bio.c | 58 ++++++++++++++++++++++++++++++++------------- include/linux/bio.h | 8 ++++--- include/linux/blkdev.h | 12 ++++++++-- 8 files changed, 80 insertions(+), 39 deletions(-) (limited to 'include/linux/bio.h') diff --git a/block/blk-map.c b/block/blk-map.c index ac21b7397e1..dad6a290783 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -41,8 +41,8 @@ static int __blk_rq_unmap_user(struct bio *bio) } static int __blk_rq_map_user(struct request_queue *q, struct request *rq, - void __user *ubuf, unsigned int len, - gfp_t gfp_mask) + struct rq_map_data *map_data, void __user *ubuf, + unsigned int len, gfp_t gfp_mask) { unsigned long uaddr; unsigned int alignment; @@ -57,10 +57,10 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq, */ uaddr = (unsigned long) ubuf; alignment = queue_dma_alignment(q) | q->dma_pad_mask; - if (!(uaddr & alignment) && !(len & alignment)) + if (!(uaddr & alignment) && !(len & alignment) && !map_data) bio = bio_map_user(q, NULL, uaddr, len, reading, gfp_mask); else - bio = bio_copy_user(q, uaddr, len, reading, gfp_mask); + bio = bio_copy_user(q, map_data, uaddr, len, reading, gfp_mask); if (IS_ERR(bio)) return PTR_ERR(bio); @@ -89,6 +89,7 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq, * blk_rq_map_user - map user data to a request, for REQ_TYPE_BLOCK_PC usage * @q: request queue where request should be inserted * @rq: request structure to fill + * @map_data: pointer to the rq_map_data holding pages (if necessary) * @ubuf: the user buffer * @len: length of user data * @gfp_mask: memory allocation flags @@ -107,7 +108,8 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq, * unmapping. */ int blk_rq_map_user(struct request_queue *q, struct request *rq, - void __user *ubuf, unsigned long len, gfp_t gfp_mask) + struct rq_map_data *map_data, void __user *ubuf, + unsigned long len, gfp_t gfp_mask) { unsigned long bytes_read = 0; struct bio *bio = NULL; @@ -134,7 +136,8 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq, if (end - start > BIO_MAX_PAGES) map_len -= PAGE_SIZE; - ret = __blk_rq_map_user(q, rq, ubuf, map_len, gfp_mask); + ret = __blk_rq_map_user(q, rq, map_data, ubuf, map_len, + gfp_mask); if (ret < 0) goto unmap_rq; if (!bio) @@ -159,6 +162,7 @@ EXPORT_SYMBOL(blk_rq_map_user); * blk_rq_map_user_iov - map user data to a request, for REQ_TYPE_BLOCK_PC usage * @q: request queue where request should be inserted * @rq: request to map data to + * @map_data: pointer to the rq_map_data holding pages (if necessary) * @iov: pointer to the iovec * @iov_count: number of elements in the iovec * @len: I/O byte count @@ -178,8 +182,8 @@ EXPORT_SYMBOL(blk_rq_map_user); * unmapping. */ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, - struct sg_iovec *iov, int iov_count, unsigned int len, - gfp_t gfp_mask) + struct rq_map_data *map_data, struct sg_iovec *iov, + int iov_count, unsigned int len, gfp_t gfp_mask) { struct bio *bio; int i, read = rq_data_dir(rq) == READ; @@ -197,8 +201,9 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, } } - if (unaligned || (q->dma_pad_mask & len)) - bio = bio_copy_user_iov(q, iov, iov_count, read, gfp_mask); + if (unaligned || (q->dma_pad_mask & len) || map_data) + bio = bio_copy_user_iov(q, map_data, iov, iov_count, read, + gfp_mask); else bio = bio_map_user_iov(q, NULL, iov, iov_count, read, gfp_mask); @@ -220,6 +225,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, rq->buffer = rq->data = NULL; return 0; } +EXPORT_SYMBOL(blk_rq_map_user_iov); /** * blk_rq_unmap_user - unmap a request with user data diff --git a/block/bsg.c b/block/bsg.c index e7a142e9916..56cb343c76d 100644 --- a/block/bsg.c +++ b/block/bsg.c @@ -283,8 +283,8 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, int has_write_perm) next_rq->cmd_type = rq->cmd_type; dxferp = (void*)(unsigned long)hdr->din_xferp; - ret = blk_rq_map_user(q, next_rq, dxferp, hdr->din_xfer_len, - GFP_KERNEL); + ret = blk_rq_map_user(q, next_rq, NULL, dxferp, + hdr->din_xfer_len, GFP_KERNEL); if (ret) goto out; } @@ -299,7 +299,8 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, int has_write_perm) dxfer_len = 0; if (dxfer_len) { - ret = blk_rq_map_user(q, rq, dxferp, dxfer_len, GFP_KERNEL); + ret = blk_rq_map_user(q, rq, NULL, dxferp, dxfer_len, + GFP_KERNEL); if (ret) goto out; } diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c index f49d6a11a69..c34272a348f 100644 --- a/block/scsi_ioctl.c +++ b/block/scsi_ioctl.c @@ -314,11 +314,11 @@ static int sg_io(struct file *file, struct request_queue *q, goto out; } - ret = blk_rq_map_user_iov(q, rq, iov, hdr->iovec_count, + ret = blk_rq_map_user_iov(q, rq, NULL, iov, hdr->iovec_count, hdr->dxfer_len, GFP_KERNEL); kfree(iov); } else if (hdr->dxfer_len) - ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len, + ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len, GFP_KERNEL); if (ret) diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c index e861d24a6d3..d47f2f80acc 100644 --- a/drivers/cdrom/cdrom.c +++ b/drivers/cdrom/cdrom.c @@ -2097,7 +2097,7 @@ static int cdrom_read_cdda_bpc(struct cdrom_device_info *cdi, __u8 __user *ubuf, len = nr * CD_FRAMESIZE_RAW; - ret = blk_rq_map_user(q, rq, ubuf, len, GFP_KERNEL); + ret = blk_rq_map_user(q, rq, NULL, ubuf, len, GFP_KERNEL); if (ret) break; diff --git a/drivers/scsi/scsi_tgt_lib.c b/drivers/scsi/scsi_tgt_lib.c index 2a4fd820d61..3117bb106b5 100644 --- a/drivers/scsi/scsi_tgt_lib.c +++ b/drivers/scsi/scsi_tgt_lib.c @@ -362,7 +362,7 @@ static int scsi_map_user_pages(struct scsi_tgt_cmd *tcmd, struct scsi_cmnd *cmd, int err; dprintk("%lx %u\n", uaddr, len); - err = blk_rq_map_user(q, rq, (void *)uaddr, len, GFP_KERNEL); + err = blk_rq_map_user(q, rq, NULL, (void *)uaddr, len, GFP_KERNEL); if (err) { /* * TODO: need to fixup sg_tablesize, max_segment_size, diff --git a/fs/bio.c b/fs/bio.c index 3d2e9ad2472..a2f072647cd 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -439,16 +439,19 @@ int bio_add_page(struct bio *bio, struct page *page, unsigned int len, struct bio_map_data { struct bio_vec *iovecs; - int nr_sgvecs; struct sg_iovec *sgvecs; + int nr_sgvecs; + int is_our_pages; }; static void bio_set_map_data(struct bio_map_data *bmd, struct bio *bio, - struct sg_iovec *iov, int iov_count) + struct sg_iovec *iov, int iov_count, + int is_our_pages) { memcpy(bmd->iovecs, bio->bi_io_vec, sizeof(struct bio_vec) * bio->bi_vcnt); memcpy(bmd->sgvecs, iov, sizeof(struct sg_iovec) * iov_count); bmd->nr_sgvecs = iov_count; + bmd->is_our_pages = is_our_pages; bio->bi_private = bmd; } @@ -483,7 +486,8 @@ static struct bio_map_data *bio_alloc_map_data(int nr_segs, int iov_count, } static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs, - struct sg_iovec *iov, int iov_count, int uncopy) + struct sg_iovec *iov, int iov_count, int uncopy, + int do_free_page) { int ret = 0, i; struct bio_vec *bvec; @@ -526,7 +530,7 @@ static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs, } } - if (uncopy) + if (do_free_page) __free_page(bvec->bv_page); } @@ -545,7 +549,8 @@ int bio_uncopy_user(struct bio *bio) struct bio_map_data *bmd = bio->bi_private; int ret; - ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs, bmd->nr_sgvecs, 1); + ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs, bmd->nr_sgvecs, 1, + bmd->is_our_pages); bio_free_map_data(bmd); bio_put(bio); @@ -555,6 +560,7 @@ int bio_uncopy_user(struct bio *bio) /** * bio_copy_user_iov - copy user data to bio * @q: destination block queue + * @map_data: pointer to the rq_map_data holding pages (if necessary) * @iov: the iovec. * @iov_count: number of elements in the iovec * @write_to_vm: bool indicating writing to pages or not @@ -564,8 +570,10 @@ int bio_uncopy_user(struct bio *bio) * to/from kernel pages as necessary. Must be paired with * call bio_uncopy_user() on io completion. */ -struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov, - int iov_count, int write_to_vm, gfp_t gfp_mask) +struct bio *bio_copy_user_iov(struct request_queue *q, + struct rq_map_data *map_data, + struct sg_iovec *iov, int iov_count, + int write_to_vm, gfp_t gfp_mask) { struct bio_map_data *bmd; struct bio_vec *bvec; @@ -600,13 +608,26 @@ struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov, bio->bi_rw |= (!write_to_vm << BIO_RW); ret = 0; + i = 0; while (len) { - unsigned int bytes = PAGE_SIZE; + unsigned int bytes; + + if (map_data) + bytes = 1U << (PAGE_SHIFT + map_data->page_order); + else + bytes = PAGE_SIZE; if (bytes > len) bytes = len; - page = alloc_page(q->bounce_gfp | gfp_mask); + if (map_data) { + if (i == map_data->nr_entries) { + ret = -ENOMEM; + break; + } + page = map_data->pages[i++]; + } else + page = alloc_page(q->bounce_gfp | gfp_mask); if (!page) { ret = -ENOMEM; break; @@ -625,16 +646,17 @@ struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov, * success */ if (!write_to_vm) { - ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0); + ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0, 0); if (ret) goto cleanup; } - bio_set_map_data(bmd, bio, iov, iov_count); + bio_set_map_data(bmd, bio, iov, iov_count, map_data ? 0 : 1); return bio; cleanup: - bio_for_each_segment(bvec, bio, i) - __free_page(bvec->bv_page); + if (!map_data) + bio_for_each_segment(bvec, bio, i) + __free_page(bvec->bv_page); bio_put(bio); out_bmd: @@ -645,6 +667,7 @@ out_bmd: /** * bio_copy_user - copy user data to bio * @q: destination block queue + * @map_data: pointer to the rq_map_data holding pages (if necessary) * @uaddr: start of user address * @len: length in bytes * @write_to_vm: bool indicating writing to pages or not @@ -654,15 +677,16 @@ out_bmd: * to/from kernel pages as necessary. Must be paired with * call bio_uncopy_user() on io completion. */ -struct bio *bio_copy_user(struct request_queue *q, unsigned long uaddr, - unsigned int len, int write_to_vm, gfp_t gfp_mask) +struct bio *bio_copy_user(struct request_queue *q, struct rq_map_data *map_data, + unsigned long uaddr, unsigned int len, + int write_to_vm, gfp_t gfp_mask) { struct sg_iovec iov; iov.iov_base = (void __user *)uaddr; iov.iov_len = len; - return bio_copy_user_iov(q, &iov, 1, write_to_vm, gfp_mask); + return bio_copy_user_iov(q, map_data, &iov, 1, write_to_vm, gfp_mask); } static struct bio *__bio_map_user_iov(struct request_queue *q, @@ -1028,7 +1052,7 @@ struct bio *bio_copy_kern(struct request_queue *q, void *data, unsigned int len, bio->bi_private = bmd; bio->bi_end_io = bio_copy_kern_endio; - bio_set_map_data(bmd, bio, &iov, 1); + bio_set_map_data(bmd, bio, &iov, 1, 1); return bio; cleanup: bio_for_each_segment(bvec, bio, i) diff --git a/include/linux/bio.h b/include/linux/bio.h index 200b185c3e8..bc386cd5e99 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -327,6 +327,7 @@ extern int bio_get_nr_vecs(struct block_device *); extern struct bio *bio_map_user(struct request_queue *, struct block_device *, unsigned long, unsigned int, int, gfp_t); struct sg_iovec; +struct rq_map_data; extern struct bio *bio_map_user_iov(struct request_queue *, struct block_device *, struct sg_iovec *, int, int, gfp_t); @@ -337,9 +338,10 @@ extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int, gfp_t, int); extern void bio_set_pages_dirty(struct bio *bio); extern void bio_check_pages_dirty(struct bio *bio); -extern struct bio *bio_copy_user(struct request_queue *, unsigned long, - unsigned int, int, gfp_t); -extern struct bio *bio_copy_user_iov(struct request_queue *, struct sg_iovec *, +extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *, + unsigned long, unsigned int, int, gfp_t); +extern struct bio *bio_copy_user_iov(struct request_queue *, + struct rq_map_data *, struct sg_iovec *, int, int, gfp_t); extern int bio_uncopy_user(struct bio *); void zero_fill_bio(struct bio *bio); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 00e388d0e22..358ac423ed2 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -642,6 +642,12 @@ static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) } #endif /* CONFIG_MMU */ +struct rq_map_data { + struct page **pages; + int page_order; + int nr_entries; +}; + struct req_iterator { int i; struct bio *bio; @@ -711,11 +717,13 @@ extern void __blk_run_queue(struct request_queue *); extern void blk_run_queue(struct request_queue *); extern void blk_start_queueing(struct request_queue *); extern int blk_rq_map_user(struct request_queue *, struct request *, - void __user *, unsigned long, gfp_t); + struct rq_map_data *, void __user *, unsigned long, + gfp_t); extern int blk_rq_unmap_user(struct bio *); extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); extern int blk_rq_map_user_iov(struct request_queue *, struct request *, - struct sg_iovec *, int, unsigned int, gfp_t); + struct rq_map_data *, struct sg_iovec *, int, + unsigned int, gfp_t); extern int blk_execute_rq(struct request_queue *, struct gendisk *, struct request *, int); extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, -- cgit v1.2.3-70-g09d2 From 818827669d85b84241696ffef2de485db46b0b5e Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Tue, 2 Sep 2008 16:20:19 +0900 Subject: block: make blk_rq_map_user take a NULL user-space buffer This patch changes blk_rq_map_user to accept a NULL user-space buffer with a READ command if rq_map_data is not NULL. Thus a caller can pass page frames to lk_rq_map_user to just set up a request and bios with page frames propely. bio_uncopy_user (called via blk_rq_unmap_user) doesn't copy data to user space with such request. Signed-off-by: FUJITA Tomonori Signed-off-by: Jens Axboe --- block/blk-map.c | 16 ++++++++++++---- fs/bio.c | 8 ++++---- include/linux/bio.h | 1 + 3 files changed, 17 insertions(+), 8 deletions(-) (limited to 'include/linux/bio.h') diff --git a/block/blk-map.c b/block/blk-map.c index 572140cda5f..4849fa36161 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -42,7 +42,7 @@ static int __blk_rq_unmap_user(struct bio *bio) static int __blk_rq_map_user(struct request_queue *q, struct request *rq, struct rq_map_data *map_data, void __user *ubuf, - unsigned int len, gfp_t gfp_mask) + unsigned int len, int null_mapped, gfp_t gfp_mask) { unsigned long uaddr; struct bio *bio, *orig_bio; @@ -63,6 +63,9 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq, if (IS_ERR(bio)) return PTR_ERR(bio); + if (null_mapped) + bio->bi_flags |= (1 << BIO_NULL_MAPPED); + orig_bio = bio; blk_queue_bounce(q, &bio); @@ -111,12 +114,17 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq, { unsigned long bytes_read = 0; struct bio *bio = NULL; - int ret; + int ret, null_mapped = 0; if (len > (q->max_hw_sectors << 9)) return -EINVAL; - if (!len || !ubuf) + if (!len) return -EINVAL; + if (!ubuf) { + if (!map_data || rq_data_dir(rq) != READ) + return -EINVAL; + null_mapped = 1; + } while (bytes_read != len) { unsigned long map_len, end, start; @@ -135,7 +143,7 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq, map_len -= PAGE_SIZE; ret = __blk_rq_map_user(q, rq, map_data, ubuf, map_len, - gfp_mask); + null_mapped, gfp_mask); if (ret < 0) goto unmap_rq; if (!bio) diff --git a/fs/bio.c b/fs/bio.c index 9d68ddb89b7..355302985e2 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -547,11 +547,11 @@ static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs, int bio_uncopy_user(struct bio *bio) { struct bio_map_data *bmd = bio->bi_private; - int ret; - - ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs, bmd->nr_sgvecs, 1, - bmd->is_our_pages); + int ret = 0; + if (!bio_flagged(bio, BIO_NULL_MAPPED)) + ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs, + bmd->nr_sgvecs, 1, bmd->is_our_pages); bio_free_map_data(bmd); bio_put(bio); return ret; diff --git a/include/linux/bio.h b/include/linux/bio.h index bc386cd5e99..7af373f253d 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -108,6 +108,7 @@ struct bio { #define BIO_USER_MAPPED 6 /* contains user pages */ #define BIO_EOPNOTSUPP 7 /* not supported */ #define BIO_CPU_AFFINE 8 /* complete bio on same CPU as submitted */ +#define BIO_NULL_MAPPED 9 /* contains invalid user pages */ #define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag))) /* -- cgit v1.2.3-70-g09d2 From 0a0d96b03a1f3bfd6bc3ea08008699e8e59fccd9 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 11 Sep 2008 13:17:37 +0200 Subject: block: add bio_kmalloc() Not all callers need (or want!) the mempool backing guarentee, it essentially means that you can only use bio_alloc() for short allocations and not for preallocating some bio's at setup or init time. So add bio_kmalloc() which does the same thing as bio_alloc(), except it just uses kmalloc() as the backing instead of the bio mempools. Signed-off-by: Jens Axboe --- fs/bio.c | 96 +++++++++++++++++++++++++++++++++++++++++------------ include/linux/bio.h | 1 + 2 files changed, 76 insertions(+), 21 deletions(-) (limited to 'include/linux/bio.h') diff --git a/fs/bio.c b/fs/bio.c index 355302985e2..e56e7685af9 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -60,25 +60,46 @@ struct bio_vec *bvec_alloc_bs(gfp_t gfp_mask, int nr, unsigned long *idx, struct struct bio_vec *bvl; /* - * see comment near bvec_array define! + * If 'bs' is given, lookup the pool and do the mempool alloc. + * If not, this is a bio_kmalloc() allocation and just do a + * kzalloc() for the exact number of vecs right away. */ - switch (nr) { - case 1 : *idx = 0; break; - case 2 ... 4: *idx = 1; break; - case 5 ... 16: *idx = 2; break; - case 17 ... 64: *idx = 3; break; - case 65 ... 128: *idx = 4; break; - case 129 ... BIO_MAX_PAGES: *idx = 5; break; + if (bs) { + /* + * see comment near bvec_array define! + */ + switch (nr) { + case 1: + *idx = 0; + break; + case 2 ... 4: + *idx = 1; + break; + case 5 ... 16: + *idx = 2; + break; + case 17 ... 64: + *idx = 3; + break; + case 65 ... 128: + *idx = 4; + break; + case 129 ... BIO_MAX_PAGES: + *idx = 5; + break; default: return NULL; - } - /* - * idx now points to the pool we want to allocate from - */ + } - bvl = mempool_alloc(bs->bvec_pools[*idx], gfp_mask); - if (bvl) - memset(bvl, 0, bvec_nr_vecs(*idx) * sizeof(struct bio_vec)); + /* + * idx now points to the pool we want to allocate from + */ + bvl = mempool_alloc(bs->bvec_pools[*idx], gfp_mask); + if (bvl) + memset(bvl, 0, + bvec_nr_vecs(*idx) * sizeof(struct bio_vec)); + } else + bvl = kzalloc(nr * sizeof(struct bio_vec), gfp_mask); return bvl; } @@ -107,6 +128,12 @@ static void bio_fs_destructor(struct bio *bio) bio_free(bio, fs_bio_set); } +static void bio_kmalloc_destructor(struct bio *bio) +{ + kfree(bio->bi_io_vec); + kfree(bio); +} + void bio_init(struct bio *bio) { memset(bio, 0, sizeof(*bio)); @@ -119,19 +146,25 @@ void bio_init(struct bio *bio) * bio_alloc_bioset - allocate a bio for I/O * @gfp_mask: the GFP_ mask given to the slab allocator * @nr_iovecs: number of iovecs to pre-allocate - * @bs: the bio_set to allocate from + * @bs: the bio_set to allocate from. If %NULL, just use kmalloc * * Description: - * bio_alloc_bioset will first try it's on mempool to satisfy the allocation. + * bio_alloc_bioset will first try its own mempool to satisfy the allocation. * If %__GFP_WAIT is set then we will block on the internal pool waiting - * for a &struct bio to become free. + * for a &struct bio to become free. If a %NULL @bs is passed in, we will + * fall back to just using @kmalloc to allocate the required memory. * * allocate bio and iovecs from the memory pools specified by the - * bio_set structure. + * bio_set structure, or @kmalloc if none given. **/ struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs) { - struct bio *bio = mempool_alloc(bs->bio_pool, gfp_mask); + struct bio *bio; + + if (bs) + bio = mempool_alloc(bs->bio_pool, gfp_mask); + else + bio = kmalloc(sizeof(*bio), gfp_mask); if (likely(bio)) { struct bio_vec *bvl = NULL; @@ -142,7 +175,10 @@ struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs) bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx, bs); if (unlikely(!bvl)) { - mempool_free(bio, bs->bio_pool); + if (bs) + mempool_free(bio, bs->bio_pool); + else + kfree(bio); bio = NULL; goto out; } @@ -165,6 +201,23 @@ struct bio *bio_alloc(gfp_t gfp_mask, int nr_iovecs) return bio; } +/* + * Like bio_alloc(), but doesn't use a mempool backing. This means that + * it CAN fail, but while bio_alloc() can only be used for allocations + * that have a short (finite) life span, bio_kmalloc() should be used + * for more permanent bio allocations (like allocating some bio's for + * initalization or setup purposes). + */ +struct bio *bio_kmalloc(gfp_t gfp_mask, int nr_iovecs) +{ + struct bio *bio = bio_alloc_bioset(gfp_mask, nr_iovecs, NULL); + + if (bio) + bio->bi_destructor = bio_kmalloc_destructor; + + return bio; +} + void zero_fill_bio(struct bio *bio) { unsigned long flags; @@ -1349,6 +1402,7 @@ static int __init init_bio(void) subsys_initcall(init_bio); EXPORT_SYMBOL(bio_alloc); +EXPORT_SYMBOL(bio_kmalloc); EXPORT_SYMBOL(bio_put); EXPORT_SYMBOL(bio_free); EXPORT_SYMBOL(bio_endio); diff --git a/include/linux/bio.h b/include/linux/bio.h index 7af373f253d..6520ee1a3f6 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -308,6 +308,7 @@ extern struct bio_set *bioset_create(int, int); extern void bioset_free(struct bio_set *); extern struct bio *bio_alloc(gfp_t, int); +extern struct bio *bio_kmalloc(gfp_t, int); extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *); extern void bio_put(struct bio *); extern void bio_free(struct bio *, struct bio_set *); -- cgit v1.2.3-70-g09d2 From 8deaf7210728c453295dc1cb2a5b66c68183ac85 Mon Sep 17 00:00:00 2001 From: Alberto Bertogli Date: Thu, 2 Oct 2008 12:46:53 +0200 Subject: bio.h: Remove unused conditional code The whole bio_integrity() definition is inside an #ifdef CONFIG_BLK_DEV_INTEGRITY, there's no need for the conditional code. Signed-off-by: Alberto Bertogli Signed-off-by: Jens Axboe --- include/linux/bio.h | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) (limited to 'include/linux/bio.h') diff --git a/include/linux/bio.h b/include/linux/bio.h index 6520ee1a3f6..98c2d057065 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -457,14 +457,7 @@ static inline int bio_has_data(struct bio *bio) #define bip_for_each_vec(bvl, bip, i) \ __bip_for_each_vec(bvl, bip, i, (bip)->bip_idx) -static inline int bio_integrity(struct bio *bio) -{ -#if defined(CONFIG_BLK_DEV_INTEGRITY) - return bio->bi_integrity != NULL; -#else - return 0; -#endif -} +#define bio_integrity(bio) (bio->bi_integrity != NULL) extern struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *, gfp_t, unsigned int, struct bio_set *); extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); -- cgit v1.2.3-70-g09d2 From 74aa8c2cc010035a7eef2b4ca4d6430e0dae206a Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Wed, 1 Oct 2008 03:38:37 -0400 Subject: block: Introduce integrity data ownership flag A filesystem might supply its own integrity metadata. Introduce a flag that indicates whether the filesystem or the block layer owns the integrity buffer. Signed-off-by: Martin K. Petersen Signed-off-by: Jens Axboe --- fs/bio-integrity.c | 3 ++- include/linux/bio.h | 1 + 2 files changed, 3 insertions(+), 1 deletion(-) (limited to 'include/linux/bio.h') diff --git a/fs/bio-integrity.c b/fs/bio-integrity.c index 6e28dcdd23a..19caf7c962a 100644 --- a/fs/bio-integrity.c +++ b/fs/bio-integrity.c @@ -107,7 +107,8 @@ void bio_integrity_free(struct bio *bio, struct bio_set *bs) BUG_ON(bip == NULL); /* A cloned bio doesn't own the integrity metadata */ - if (!bio_flagged(bio, BIO_CLONED) && bip->bip_buf != NULL) + if (!bio_flagged(bio, BIO_CLONED) && !bio_flagged(bio, BIO_FS_INTEGRITY) + && bip->bip_buf != NULL) kfree(bip->bip_buf); mempool_free(bip->bip_vec, bs->bvec_pools[bip->bip_pool]); diff --git a/include/linux/bio.h b/include/linux/bio.h index 98c2d057065..d86d39d490e 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -109,6 +109,7 @@ struct bio { #define BIO_EOPNOTSUPP 7 /* not supported */ #define BIO_CPU_AFFINE 8 /* complete bio on same CPU as submitted */ #define BIO_NULL_MAPPED 9 /* contains invalid user pages */ +#define BIO_FS_INTEGRITY 10 /* fs owns integrity data, not block layer */ #define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag))) /* -- cgit v1.2.3-70-g09d2 From ad3316bf4eeb53c89164f759767f911072b56203 Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Wed, 1 Oct 2008 22:42:53 -0400 Subject: block: Find bio sector offset given idx and offset Helper function to find the sector offset in a bio given bvec index and page offset. Signed-off-by: Martin K. Petersen Signed-off-by: Jens Axboe --- fs/bio.c | 36 ++++++++++++++++++++++++++++++++++++ include/linux/bio.h | 1 + 2 files changed, 37 insertions(+) (limited to 'include/linux/bio.h') diff --git a/fs/bio.c b/fs/bio.c index e56e7685af9..a5af5809f56 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -1300,6 +1300,42 @@ struct bio_pair *bio_split(struct bio *bi, mempool_t *pool, int first_sectors) return bp; } +/** + * bio_sector_offset - Find hardware sector offset in bio + * @bio: bio to inspect + * @index: bio_vec index + * @offset: offset in bv_page + * + * Return the number of hardware sectors between beginning of bio + * and an end point indicated by a bio_vec index and an offset + * within that vector's page. + */ +sector_t bio_sector_offset(struct bio *bio, unsigned short index, + unsigned int offset) +{ + unsigned int sector_sz = queue_hardsect_size(bio->bi_bdev->bd_disk->queue); + struct bio_vec *bv; + sector_t sectors; + int i; + + sectors = 0; + + if (index >= bio->bi_idx) + index = bio->bi_vcnt - 1; + + __bio_for_each_segment(bv, bio, i, 0) { + if (i == index) { + if (offset > bv->bv_offset) + sectors += (offset - bv->bv_offset) / sector_sz; + break; + } + + sectors += bv->bv_len / sector_sz; + } + + return sectors; +} +EXPORT_SYMBOL(bio_sector_offset); /* * create memory pools for biovec's in a bio_set. diff --git a/include/linux/bio.h b/include/linux/bio.h index d86d39d490e..fe12d0f9eba 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -327,6 +327,7 @@ extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, unsigned int, unsigned int); extern int bio_get_nr_vecs(struct block_device *); +extern sector_t bio_sector_offset(struct bio *, unsigned short, unsigned int); extern struct bio *bio_map_user(struct request_queue *, struct block_device *, unsigned long, unsigned int, int, gfp_t); struct sg_iovec; -- cgit v1.2.3-70-g09d2 From 6feef531f55cf4a20fd9eb39f5352e5745203603 Mon Sep 17 00:00:00 2001 From: Denis ChengRq Date: Thu, 9 Oct 2008 08:57:05 +0200 Subject: block: mark bio_split_pool static Since all bio_split calls refer the same single bio_split_pool, the bio_split function can use bio_split_pool directly instead of the mempool_t parameter; then the mempool_t parameter can be removed from bio_split param list, and bio_split_pool is only referred in fs/bio.c file, can be marked static. Signed-off-by: Denis ChengRq Signed-off-by: Jens Axboe --- drivers/block/pktcdvd.c | 2 +- drivers/md/linear.c | 2 +- drivers/md/raid0.c | 2 +- drivers/md/raid10.c | 2 +- fs/bio.c | 9 ++++----- include/linux/bio.h | 4 +--- 6 files changed, 9 insertions(+), 12 deletions(-) (limited to 'include/linux/bio.h') diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c index e1a90bbb474..0e077150568 100644 --- a/drivers/block/pktcdvd.c +++ b/drivers/block/pktcdvd.c @@ -2544,7 +2544,7 @@ static int pkt_make_request(struct request_queue *q, struct bio *bio) if (last_zone != zone) { BUG_ON(last_zone != zone + pd->settings.size); first_sectors = last_zone - bio->bi_sector; - bp = bio_split(bio, bio_split_pool, first_sectors); + bp = bio_split(bio, first_sectors); BUG_ON(!bp); pkt_make_request(q, &bp->bio1); pkt_make_request(q, &bp->bio2); diff --git a/drivers/md/linear.c b/drivers/md/linear.c index c80ea90593d..b9cbee688fa 100644 --- a/drivers/md/linear.c +++ b/drivers/md/linear.c @@ -353,7 +353,7 @@ static int linear_make_request (struct request_queue *q, struct bio *bio) * split it. */ struct bio_pair *bp; - bp = bio_split(bio, bio_split_pool, + bp = bio_split(bio, ((tmp_dev->offset + tmp_dev->size)<<1) - bio->bi_sector); if (linear_make_request(q, &bp->bio1)) generic_make_request(&bp->bio1); diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index f52f442a735..53508a8a981 100644 --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -427,7 +427,7 @@ static int raid0_make_request (struct request_queue *q, struct bio *bio) /* This is a one page bio that upper layers * refuse to split for us, so we need to split it. */ - bp = bio_split(bio, bio_split_pool, chunk_sects - (bio->bi_sector & (chunk_sects - 1)) ); + bp = bio_split(bio, chunk_sects - (bio->bi_sector & (chunk_sects - 1))); if (raid0_make_request(q, &bp->bio1)) generic_make_request(&bp->bio1); if (raid0_make_request(q, &bp->bio2)) diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 5f990133f5e..8bdc9bfc288 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -817,7 +817,7 @@ static int make_request(struct request_queue *q, struct bio * bio) /* This is a one page bio that upper layers * refuse to split for us, so we need to split it. */ - bp = bio_split(bio, bio_split_pool, + bp = bio_split(bio, chunk_sects - (bio->bi_sector & (chunk_sects - 1)) ); if (make_request(q, &bp->bio1)) generic_make_request(&bp->bio1); diff --git a/fs/bio.c b/fs/bio.c index a5af5809f56..77a55bcceed 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -30,7 +30,7 @@ static struct kmem_cache *bio_slab __read_mostly; -mempool_t *bio_split_pool __read_mostly; +static mempool_t *bio_split_pool __read_mostly; /* * if you change this list, also change bvec_alloc or things will @@ -1256,9 +1256,9 @@ static void bio_pair_end_2(struct bio *bi, int err) * split a bio - only worry about a bio with a single page * in it's iovec */ -struct bio_pair *bio_split(struct bio *bi, mempool_t *pool, int first_sectors) +struct bio_pair *bio_split(struct bio *bi, int first_sectors) { - struct bio_pair *bp = mempool_alloc(pool, GFP_NOIO); + struct bio_pair *bp = mempool_alloc(bio_split_pool, GFP_NOIO); if (!bp) return bp; @@ -1292,7 +1292,7 @@ struct bio_pair *bio_split(struct bio *bi, mempool_t *pool, int first_sectors) bp->bio2.bi_end_io = bio_pair_end_2; bp->bio1.bi_private = bi; - bp->bio2.bi_private = pool; + bp->bio2.bi_private = bio_split_pool; if (bio_integrity(bi)) bio_integrity_split(bi, bp, first_sectors); @@ -1455,7 +1455,6 @@ EXPORT_SYMBOL(bio_map_kern); EXPORT_SYMBOL(bio_copy_kern); EXPORT_SYMBOL(bio_pair_release); EXPORT_SYMBOL(bio_split); -EXPORT_SYMBOL(bio_split_pool); EXPORT_SYMBOL(bio_copy_user); EXPORT_SYMBOL(bio_uncopy_user); EXPORT_SYMBOL(bioset_create); diff --git a/include/linux/bio.h b/include/linux/bio.h index fe12d0f9eba..fb97221d7c3 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -300,9 +300,7 @@ struct bio_pair { atomic_t cnt; int error; }; -extern struct bio_pair *bio_split(struct bio *bi, mempool_t *pool, - int first_sectors); -extern mempool_t *bio_split_pool; +extern struct bio_pair *bio_split(struct bio *bi, int first_sectors); extern void bio_pair_release(struct bio_pair *dbio); extern struct bio_set *bioset_create(int, int); -- cgit v1.2.3-70-g09d2 From af5639424008ffe96f89b059bea1aec15e0115a9 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 9 Oct 2008 09:01:10 +0200 Subject: block: add some comments around the bio read-write flags Signed-off-by: Jens Axboe --- include/linux/bio.h | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'include/linux/bio.h') diff --git a/include/linux/bio.h b/include/linux/bio.h index fb97221d7c3..ff5b4cf9e2d 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -123,13 +123,23 @@ struct bio { /* * bio bi_rw flags * - * bit 0 -- read (not set) or write (set) + * bit 0 -- data direction + * If not set, bio is a read from device. If set, it's a write to device. * bit 1 -- rw-ahead when set * bit 2 -- barrier + * Insert a serialization point in the IO queue, forcing previously + * submitted IO to be completed before this oen is issued. * bit 3 -- fail fast, don't want low level driver retries * bit 4 -- synchronous I/O hint: the block layer will unplug immediately + * Note that this does NOT indicate that the IO itself is sync, just + * that the block layer will not postpone issue of this IO by plugging. * bit 5 -- metadata request + * Used for tracing to differentiate metadata and data IO. May also + * get some preferential treatment in the IO scheduler * bit 6 -- discard sectors + * Informs the lower level device that this range of sectors is no longer + * used by the file system and may thus be freed by the device. Used + * for flash based storage. */ #define BIO_RW 0 /* Must match RW in req flags (blkdev.h) */ #define BIO_RW_AHEAD 1 /* Must match FAILFAST in req flags */ -- cgit v1.2.3-70-g09d2 From 6000a368cd8e6da1caf101411bdb494cd6fb8b09 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Tue, 19 Aug 2008 18:45:30 -0500 Subject: [SCSI] block: separate failfast into multiple bits. Multipath is best at handling transport errors. If it gets a device error then there is not much the multipath layer can do. It will just access the same device but from a different path. This patch breaks up failfast into device, transport and driver errors. The multipath layers (md and dm mutlipath) only ask the lower levels to fast fail transport errors. The user of failfast, read ahead, will ask to fast fail on all errors. Note that blk_noretry_request will return true if any failfast bit is set. This allows drivers that do not support the multipath failfast bits to continue to fail on any failfast error like before. Drivers like scsi that are able to fail fast specific errors can check for the specific fail fast type. In the next patch I will convert scsi. Signed-off-by: Mike Christie Cc: Jens Axboe Signed-off-by: James Bottomley --- block/blk-core.c | 11 +++++++++-- drivers/md/dm-mpath.c | 2 +- drivers/md/multipath.c | 4 ++-- drivers/s390/block/dasd_diag.c | 2 +- drivers/s390/block/dasd_eckd.c | 2 +- drivers/s390/block/dasd_fba.c | 2 +- drivers/scsi/device_handler/scsi_dh_alua.c | 3 ++- drivers/scsi/device_handler/scsi_dh_emc.c | 3 ++- drivers/scsi/device_handler/scsi_dh_hp_sw.c | 6 ++++-- drivers/scsi/device_handler/scsi_dh_rdac.c | 3 ++- drivers/scsi/scsi_transport_spi.c | 4 +++- include/linux/bio.h | 26 +++++++++++++++++--------- include/linux/blkdev.h | 15 ++++++++++++--- 13 files changed, 57 insertions(+), 26 deletions(-) (limited to 'include/linux/bio.h') diff --git a/block/blk-core.c b/block/blk-core.c index 2d053b58441..9e79a485e4f 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1075,8 +1075,15 @@ void init_request_from_bio(struct request *req, struct bio *bio) /* * inherit FAILFAST from bio (for read-ahead, and explicit FAILFAST) */ - if (bio_rw_ahead(bio) || bio_failfast(bio)) - req->cmd_flags |= REQ_FAILFAST; + if (bio_rw_ahead(bio)) + req->cmd_flags |= (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | + REQ_FAILFAST_DRIVER); + if (bio_failfast_dev(bio)) + req->cmd_flags |= REQ_FAILFAST_DEV; + if (bio_failfast_transport(bio)) + req->cmd_flags |= REQ_FAILFAST_TRANSPORT; + if (bio_failfast_driver(bio)) + req->cmd_flags |= REQ_FAILFAST_DRIVER; /* * REQ_BARRIER implies no merging, but lets make it explicit diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index 103304c1e3b..9bf3460c554 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -849,7 +849,7 @@ static int multipath_map(struct dm_target *ti, struct bio *bio, dm_bio_record(&mpio->details, bio); map_context->ptr = mpio; - bio->bi_rw |= (1 << BIO_RW_FAILFAST); + bio->bi_rw |= (1 << BIO_RW_FAILFAST_TRANSPORT); r = map_io(m, bio, mpio, 0); if (r < 0 || r == DM_MAPIO_REQUEUE) mempool_free(mpio, m->mpio_pool); diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c index 8bb8794129b..7ae33ebaf7e 100644 --- a/drivers/md/multipath.c +++ b/drivers/md/multipath.c @@ -176,7 +176,7 @@ static int multipath_make_request (struct request_queue *q, struct bio * bio) mp_bh->bio = *bio; mp_bh->bio.bi_sector += multipath->rdev->data_offset; mp_bh->bio.bi_bdev = multipath->rdev->bdev; - mp_bh->bio.bi_rw |= (1 << BIO_RW_FAILFAST); + mp_bh->bio.bi_rw |= (1 << BIO_RW_FAILFAST_TRANSPORT); mp_bh->bio.bi_end_io = multipath_end_request; mp_bh->bio.bi_private = mp_bh; generic_make_request(&mp_bh->bio); @@ -402,7 +402,7 @@ static void multipathd (mddev_t *mddev) *bio = *(mp_bh->master_bio); bio->bi_sector += conf->multipaths[mp_bh->path].rdev->data_offset; bio->bi_bdev = conf->multipaths[mp_bh->path].rdev->bdev; - bio->bi_rw |= (1 << BIO_RW_FAILFAST); + bio->bi_rw |= (1 << BIO_RW_FAILFAST_TRANSPORT); bio->bi_end_io = multipath_end_request; bio->bi_private = mp_bh; generic_make_request(bio); diff --git a/drivers/s390/block/dasd_diag.c b/drivers/s390/block/dasd_diag.c index 85fcb437105..7844461a995 100644 --- a/drivers/s390/block/dasd_diag.c +++ b/drivers/s390/block/dasd_diag.c @@ -544,7 +544,7 @@ static struct dasd_ccw_req *dasd_diag_build_cp(struct dasd_device *memdev, } cqr->retries = DIAG_MAX_RETRIES; cqr->buildclk = get_clock(); - if (req->cmd_flags & REQ_FAILFAST) + if (blk_noretry_request(req)) set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); cqr->startdev = memdev; cqr->memdev = memdev; diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c index 49f9d221e23..2e60d5f968c 100644 --- a/drivers/s390/block/dasd_eckd.c +++ b/drivers/s390/block/dasd_eckd.c @@ -1700,7 +1700,7 @@ static struct dasd_ccw_req *dasd_eckd_build_cp(struct dasd_device *startdev, recid++; } } - if (req->cmd_flags & REQ_FAILFAST) + if (blk_noretry_request(req)) set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); cqr->startdev = startdev; cqr->memdev = startdev; diff --git a/drivers/s390/block/dasd_fba.c b/drivers/s390/block/dasd_fba.c index 93d9b6452a9..7d442aeff3d 100644 --- a/drivers/s390/block/dasd_fba.c +++ b/drivers/s390/block/dasd_fba.c @@ -355,7 +355,7 @@ static struct dasd_ccw_req *dasd_fba_build_cp(struct dasd_device * memdev, recid++; } } - if (req->cmd_flags & REQ_FAILFAST) + if (blk_noretry_request(req)) set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); cqr->startdev = memdev; cqr->memdev = memdev; diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 708e475896b..cb8aa3b58c2 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -109,7 +109,8 @@ static struct request *get_alua_req(struct scsi_device *sdev, } rq->cmd_type = REQ_TYPE_BLOCK_PC; - rq->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE; + rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | + REQ_FAILFAST_DRIVER | REQ_NOMERGE; rq->retries = ALUA_FAILOVER_RETRIES; rq->timeout = ALUA_FAILOVER_TIMEOUT; diff --git a/drivers/scsi/device_handler/scsi_dh_emc.c b/drivers/scsi/device_handler/scsi_dh_emc.c index 8f45570a8a0..0e572d2c5b0 100644 --- a/drivers/scsi/device_handler/scsi_dh_emc.c +++ b/drivers/scsi/device_handler/scsi_dh_emc.c @@ -303,7 +303,8 @@ static struct request *get_req(struct scsi_device *sdev, int cmd, rq->cmd[4] = len; rq->cmd_type = REQ_TYPE_BLOCK_PC; - rq->cmd_flags |= REQ_FAILFAST; + rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | + REQ_FAILFAST_DRIVER; rq->timeout = CLARIION_TIMEOUT; rq->retries = CLARIION_RETRIES; diff --git a/drivers/scsi/device_handler/scsi_dh_hp_sw.c b/drivers/scsi/device_handler/scsi_dh_hp_sw.c index 5e93c88ad66..9aec4ca64e5 100644 --- a/drivers/scsi/device_handler/scsi_dh_hp_sw.c +++ b/drivers/scsi/device_handler/scsi_dh_hp_sw.c @@ -112,7 +112,8 @@ static int hp_sw_tur(struct scsi_device *sdev, struct hp_sw_dh_data *h) return SCSI_DH_RES_TEMP_UNAVAIL; req->cmd_type = REQ_TYPE_BLOCK_PC; - req->cmd_flags |= REQ_FAILFAST; + req->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | + REQ_FAILFAST_DRIVER; req->cmd_len = COMMAND_SIZE(TEST_UNIT_READY); req->cmd[0] = TEST_UNIT_READY; req->timeout = HP_SW_TIMEOUT; @@ -204,7 +205,8 @@ static int hp_sw_start_stop(struct scsi_device *sdev, struct hp_sw_dh_data *h) return SCSI_DH_RES_TEMP_UNAVAIL; req->cmd_type = REQ_TYPE_BLOCK_PC; - req->cmd_flags |= REQ_FAILFAST; + req->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | + REQ_FAILFAST_DRIVER; req->cmd_len = COMMAND_SIZE(START_STOP); req->cmd[0] = START_STOP; req->cmd[4] = 1; /* Start spin cycle */ diff --git a/drivers/scsi/device_handler/scsi_dh_rdac.c b/drivers/scsi/device_handler/scsi_dh_rdac.c index 50bf95f3b5c..a43c3ed4df2 100644 --- a/drivers/scsi/device_handler/scsi_dh_rdac.c +++ b/drivers/scsi/device_handler/scsi_dh_rdac.c @@ -226,7 +226,8 @@ static struct request *get_rdac_req(struct scsi_device *sdev, } rq->cmd_type = REQ_TYPE_BLOCK_PC; - rq->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE; + rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | + REQ_FAILFAST_DRIVER; rq->retries = RDAC_RETRIES; rq->timeout = RDAC_TIMEOUT; diff --git a/drivers/scsi/scsi_transport_spi.c b/drivers/scsi/scsi_transport_spi.c index b29360ed0bd..7c2d28924d2 100644 --- a/drivers/scsi/scsi_transport_spi.c +++ b/drivers/scsi/scsi_transport_spi.c @@ -109,7 +109,9 @@ static int spi_execute(struct scsi_device *sdev, const void *cmd, for(i = 0; i < DV_RETRIES; i++) { result = scsi_execute(sdev, cmd, dir, buffer, bufflen, sense, DV_TIMEOUT, /* retries */ 1, - REQ_FAILFAST); + REQ_FAILFAST_DEV | + REQ_FAILFAST_TRANSPORT | + REQ_FAILFAST_DRIVER); if (result & DRIVER_SENSE) { struct scsi_sense_hdr sshdr_tmp; if (!sshdr) diff --git a/include/linux/bio.h b/include/linux/bio.h index ff5b4cf9e2d..1beda208cbf 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -129,25 +129,30 @@ struct bio { * bit 2 -- barrier * Insert a serialization point in the IO queue, forcing previously * submitted IO to be completed before this oen is issued. - * bit 3 -- fail fast, don't want low level driver retries - * bit 4 -- synchronous I/O hint: the block layer will unplug immediately + * bit 3 -- synchronous I/O hint: the block layer will unplug immediately * Note that this does NOT indicate that the IO itself is sync, just * that the block layer will not postpone issue of this IO by plugging. - * bit 5 -- metadata request + * bit 4 -- metadata request * Used for tracing to differentiate metadata and data IO. May also * get some preferential treatment in the IO scheduler - * bit 6 -- discard sectors + * bit 5 -- discard sectors * Informs the lower level device that this range of sectors is no longer * used by the file system and may thus be freed by the device. Used * for flash based storage. + * bit 6 -- fail fast device errors + * bit 7 -- fail fast transport errors + * bit 8 -- fail fast driver errors + * Don't want driver retries for any fast fail whatever the reason. */ #define BIO_RW 0 /* Must match RW in req flags (blkdev.h) */ #define BIO_RW_AHEAD 1 /* Must match FAILFAST in req flags */ #define BIO_RW_BARRIER 2 -#define BIO_RW_FAILFAST 3 -#define BIO_RW_SYNC 4 -#define BIO_RW_META 5 -#define BIO_RW_DISCARD 6 +#define BIO_RW_SYNC 3 +#define BIO_RW_META 4 +#define BIO_RW_DISCARD 5 +#define BIO_RW_FAILFAST_DEV 6 +#define BIO_RW_FAILFAST_TRANSPORT 7 +#define BIO_RW_FAILFAST_DRIVER 8 /* * upper 16 bits of bi_rw define the io priority of this bio @@ -174,7 +179,10 @@ struct bio { #define bio_sectors(bio) ((bio)->bi_size >> 9) #define bio_barrier(bio) ((bio)->bi_rw & (1 << BIO_RW_BARRIER)) #define bio_sync(bio) ((bio)->bi_rw & (1 << BIO_RW_SYNC)) -#define bio_failfast(bio) ((bio)->bi_rw & (1 << BIO_RW_FAILFAST)) +#define bio_failfast_dev(bio) ((bio)->bi_rw & (1 << BIO_RW_FAILFAST_DEV)) +#define bio_failfast_transport(bio) \ + ((bio)->bi_rw & (1 << BIO_RW_FAILFAST_TRANSPORT)) +#define bio_failfast_driver(bio) ((bio)->bi_rw & (1 << BIO_RW_FAILFAST_DRIVER)) #define bio_rw_ahead(bio) ((bio)->bi_rw & (1 << BIO_RW_AHEAD)) #define bio_rw_meta(bio) ((bio)->bi_rw & (1 << BIO_RW_META)) #define bio_discard(bio) ((bio)->bi_rw & (1 << BIO_RW_DISCARD)) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index a92d9e4ea96..f3491d22526 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -87,7 +87,9 @@ enum { */ enum rq_flag_bits { __REQ_RW, /* not set, read. set, write */ - __REQ_FAILFAST, /* no low level driver retries */ + __REQ_FAILFAST_DEV, /* no driver retries of device errors */ + __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */ + __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */ __REQ_DISCARD, /* request to discard sectors */ __REQ_SORTED, /* elevator knows about this request */ __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */ @@ -111,8 +113,10 @@ enum rq_flag_bits { }; #define REQ_RW (1 << __REQ_RW) +#define REQ_FAILFAST_DEV (1 << __REQ_FAILFAST_DEV) +#define REQ_FAILFAST_TRANSPORT (1 << __REQ_FAILFAST_TRANSPORT) +#define REQ_FAILFAST_DRIVER (1 << __REQ_FAILFAST_DRIVER) #define REQ_DISCARD (1 << __REQ_DISCARD) -#define REQ_FAILFAST (1 << __REQ_FAILFAST) #define REQ_SORTED (1 << __REQ_SORTED) #define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER) #define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER) @@ -560,7 +564,12 @@ enum { #define blk_special_request(rq) ((rq)->cmd_type == REQ_TYPE_SPECIAL) #define blk_sense_request(rq) ((rq)->cmd_type == REQ_TYPE_SENSE) -#define blk_noretry_request(rq) ((rq)->cmd_flags & REQ_FAILFAST) +#define blk_failfast_dev(rq) ((rq)->cmd_flags & REQ_FAILFAST_DEV) +#define blk_failfast_transport(rq) ((rq)->cmd_flags & REQ_FAILFAST_TRANSPORT) +#define blk_failfast_driver(rq) ((rq)->cmd_flags & REQ_FAILFAST_DRIVER) +#define blk_noretry_request(rq) (blk_failfast_dev(rq) || \ + blk_failfast_transport(rq) || \ + blk_failfast_driver(rq)) #define blk_rq_started(rq) ((rq)->cmd_flags & REQ_STARTED) #define blk_account_rq(rq) (blk_rq_started(rq) && (blk_fs_request(rq) || blk_discard_rq(rq))) -- cgit v1.2.3-70-g09d2 From 8677142710516d986d932d6f1fba7be8382c1fec Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Mon, 13 Oct 2008 14:19:05 +0200 Subject: block: fix nr_phys_segments miscalculation bug This fixes the bug reported by Nikanth Karthikesan : http://lkml.org/lkml/2008/10/2/203 The root cause of the bug is that blk_phys_contig_segment miscalculates q->max_segment_size. blk_phys_contig_segment checks: req->biotail->bi_size + next_req->bio->bi_size > q->max_segment_size But blk_recalc_rq_segments might expect that req->biotail and the previous bio in the req are supposed be merged into one segment. blk_recalc_rq_segments might also expect that next_req->bio and the next bio in the next_req are supposed be merged into one segment. In such case, we merge two requests that can't be merged here. Later, blk_rq_map_sg gives more segments than it should. We need to keep track of segment size in blk_recalc_rq_segments and use it to see if two requests can be merged. This patch implements it in the similar way that we used to do for hw merging (virtual merging). Signed-off-by: FUJITA Tomonori Signed-off-by: Jens Axboe --- block/blk-merge.c | 20 ++++++++++++++++++-- include/linux/bio.h | 7 +++++++ 2 files changed, 25 insertions(+), 2 deletions(-) (limited to 'include/linux/bio.h') diff --git a/block/blk-merge.c b/block/blk-merge.c index 908d3e11ac5..8681cd6f991 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -77,12 +77,20 @@ void blk_recalc_rq_segments(struct request *rq) continue; } new_segment: + if (nr_phys_segs == 1 && seg_size > rq->bio->bi_seg_front_size) + rq->bio->bi_seg_front_size = seg_size; + nr_phys_segs++; bvprv = bv; seg_size = bv->bv_len; highprv = high; } + if (nr_phys_segs == 1 && seg_size > rq->bio->bi_seg_front_size) + rq->bio->bi_seg_front_size = seg_size; + if (seg_size > rq->biotail->bi_seg_back_size) + rq->biotail->bi_seg_back_size = seg_size; + rq->nr_phys_segments = nr_phys_segs; } @@ -106,7 +114,8 @@ static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio, if (!test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags)) return 0; - if (bio->bi_size + nxt->bi_size > q->max_segment_size) + if (bio->bi_seg_back_size + nxt->bi_seg_front_size > + q->max_segment_size) return 0; if (!bio_has_data(bio)) @@ -309,6 +318,8 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req, struct request *next) { int total_phys_segments; + unsigned int seg_size = + req->biotail->bi_seg_back_size + next->bio->bi_seg_front_size; /* * First check if the either of the requests are re-queued @@ -324,8 +335,13 @@ 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 (blk_phys_contig_segment(q, req->biotail, next->bio)) + if (blk_phys_contig_segment(q, req->biotail, next->bio)) { + if (req->nr_phys_segments == 1) + req->bio->bi_seg_front_size = seg_size; + if (next->nr_phys_segments == 1) + next->biotail->bi_seg_back_size = seg_size; total_phys_segments--; + } if (total_phys_segments > q->max_phys_segments) return 0; diff --git a/include/linux/bio.h b/include/linux/bio.h index ff5b4cf9e2d..dc3cec386a9 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -79,6 +79,13 @@ struct bio { unsigned int bi_size; /* residual I/O count */ + /* + * To keep track of the max segment size, we account for the + * sizes of the first and last mergeable segments in this bio. + */ + unsigned int bi_seg_front_size; + unsigned int bi_seg_back_size; + unsigned int bi_max_vecs; /* max bvl_vecs we can hold */ unsigned int bi_comp_cpu; /* completion CPU */ -- cgit v1.2.3-70-g09d2