From e73c23ff736e1ea371dfa419d7bf8e77ee53044a Mon Sep 17 00:00:00 2001 From: Chaitanya Kulkarni Date: Wed, 30 Nov 2016 12:28:58 -0800 Subject: [PATCH] block: add async variant of blkdev_issue_zeroout Similar to __blkdev_issue_discard this variant allows submitting the final bio asynchronously and chaining multiple ranges into a single completion. Signed-off-by: Chaitanya Kulkarni Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-lib.c | 115 +++++++++++++++++++++++++++++------------ include/linux/blkdev.h | 3 ++ 2 files changed, 84 insertions(+), 34 deletions(-) diff --git a/block/blk-lib.c b/block/blk-lib.c index 18abda862915..bfb28b03765e 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -137,24 +137,24 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, EXPORT_SYMBOL(blkdev_issue_discard); /** - * blkdev_issue_write_same - queue a write same operation + * __blkdev_issue_write_same - generate number of bios with same page * @bdev: target blockdev * @sector: start sector * @nr_sects: number of sectors to write * @gfp_mask: memory allocation flags (for bio_alloc) * @page: page containing data to write + * @biop: pointer to anchor bio * * Description: - * Issue a write same request for the sectors in question. + * Generate and issue number of bios(REQ_OP_WRITE_SAME) with same page. */ -int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, - sector_t nr_sects, gfp_t gfp_mask, - struct page *page) +static int __blkdev_issue_write_same(struct block_device *bdev, sector_t sector, + sector_t nr_sects, gfp_t gfp_mask, struct page *page, + struct bio **biop) { struct request_queue *q = bdev_get_queue(bdev); unsigned int max_write_same_sectors; - struct bio *bio = NULL; - int ret = 0; + struct bio *bio = *biop; sector_t bs_mask; if (!q) @@ -164,6 +164,9 @@ int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, if ((sector | nr_sects) & bs_mask) return -EINVAL; + if (!bdev_write_same(bdev)) + return -EOPNOTSUPP; + /* Ensure that max_write_same_sectors doesn't overflow bi_size */ max_write_same_sectors = UINT_MAX >> 9; @@ -185,32 +188,63 @@ int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, bio->bi_iter.bi_size = nr_sects << 9; nr_sects = 0; } + cond_resched(); } - if (bio) { + *biop = bio; + return 0; +} + +/** + * blkdev_issue_write_same - queue a write same operation + * @bdev: target blockdev + * @sector: start sector + * @nr_sects: number of sectors to write + * @gfp_mask: memory allocation flags (for bio_alloc) + * @page: page containing data + * + * Description: + * Issue a write same request for the sectors in question. + */ +int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, + sector_t nr_sects, gfp_t gfp_mask, + struct page *page) +{ + struct bio *bio = NULL; + struct blk_plug plug; + int ret; + + blk_start_plug(&plug); + ret = __blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask, page, + &bio); + if (ret == 0 && bio) { ret = submit_bio_wait(bio); bio_put(bio); } + blk_finish_plug(&plug); return ret; } EXPORT_SYMBOL(blkdev_issue_write_same); /** - * blkdev_issue_zeroout - generate number of zero filed write bios + * __blkdev_issue_zeroout - generate number of zero filed write bios * @bdev: blockdev to issue * @sector: start sector * @nr_sects: number of sectors to write * @gfp_mask: memory allocation flags (for bio_alloc) + * @biop: pointer to anchor bio + * @discard: discard flag * * Description: * Generate and issue number of bios with zerofiled pages. */ - -static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, - sector_t nr_sects, gfp_t gfp_mask) +int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, + sector_t nr_sects, gfp_t gfp_mask, struct bio **biop, + bool discard) { int ret; - struct bio *bio = NULL; + int bi_size = 0; + struct bio *bio = *biop; unsigned int sz; sector_t bs_mask; @@ -218,6 +252,19 @@ static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, if ((sector | nr_sects) & bs_mask) return -EINVAL; + if (discard) { + ret = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, + BLKDEV_DISCARD_ZERO, biop); + if (ret == 0 || (ret && ret != -EOPNOTSUPP)) + goto out; + } + + ret = __blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask, + ZERO_PAGE(0), biop); + if (ret == 0 || (ret && ret != -EOPNOTSUPP)) + goto out; + + ret = 0; while (nr_sects != 0) { bio = next_bio(bio, min(nr_sects, (sector_t)BIO_MAX_PAGES), gfp_mask); @@ -227,21 +274,20 @@ static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, while (nr_sects != 0) { sz = min((sector_t) PAGE_SIZE >> 9 , nr_sects); - ret = bio_add_page(bio, ZERO_PAGE(0), sz << 9, 0); - nr_sects -= ret >> 9; - sector += ret >> 9; - if (ret < (sz << 9)) + bi_size = bio_add_page(bio, ZERO_PAGE(0), sz << 9, 0); + nr_sects -= bi_size >> 9; + sector += bi_size >> 9; + if (bi_size < (sz << 9)) break; } + cond_resched(); } - if (bio) { - ret = submit_bio_wait(bio); - bio_put(bio); - return ret; - } - return 0; + *biop = bio; +out: + return ret; } +EXPORT_SYMBOL(__blkdev_issue_zeroout); /** * blkdev_issue_zeroout - zero-fill a block range @@ -263,21 +309,22 @@ static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, * clearing the block range. Otherwise the zeroing will be performed * using regular WRITE calls. */ - int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, sector_t nr_sects, gfp_t gfp_mask, bool discard) { - if (discard) { - if (!blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, - BLKDEV_DISCARD_ZERO)) - return 0; - } + int ret; + struct bio *bio = NULL; + struct blk_plug plug; - if (bdev_write_same(bdev) && - blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask, - ZERO_PAGE(0)) == 0) - return 0; + blk_start_plug(&plug); + ret = __blkdev_issue_zeroout(bdev, sector, nr_sects, gfp_mask, + &bio, discard); + if (ret == 0 && bio) { + ret = submit_bio_wait(bio); + bio_put(bio); + } + blk_finish_plug(&plug); - return __blkdev_issue_zeroout(bdev, sector, nr_sects, gfp_mask); + return ret; } EXPORT_SYMBOL(blkdev_issue_zeroout); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 541fdd8787a5..7e9d8a0895be 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1269,6 +1269,9 @@ extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, struct bio **biop); extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, sector_t nr_sects, gfp_t gfp_mask, struct page *page); +extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, + sector_t nr_sects, gfp_t gfp_mask, struct bio **biop, + bool discard); extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, sector_t nr_sects, gfp_t gfp_mask, bool discard); static inline int sb_issue_discard(struct super_block *sb, sector_t block, -- 2.20.1