diff options
| -rw-r--r-- | block/blk-barrier.c | 69 | ||||
| -rw-r--r-- | block/blk-core.c | 28 | ||||
| -rw-r--r-- | block/blk-settings.c | 17 | ||||
| -rw-r--r-- | include/linux/bio.h | 8 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 16 | ||||
| -rw-r--r-- | include/linux/fs.h | 3 |
6 files changed, 130 insertions, 11 deletions
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 @@ -33,6 +33,23 @@ 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 * @mbfn: merge_bvec_fn 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 |