From 3dba53a958a758fe7bed5002f6a2846e1acefe8e Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Mon, 2 May 2016 20:16:21 -0400 Subject: [PATCH] dm thin: use __blkdev_issue_discard for async discard support With commit 38f25255330 ("block: add __blkdev_issue_discard") DM thinp no longer needs to carry its own async discard method. Signed-off-by: Mike Snitzer Acked-by: Joe Thornber Reviewed-by: Christoph Hellwig --- drivers/md/dm-thin.c | 70 ++++++++++---------------------------------- 1 file changed, 16 insertions(+), 54 deletions(-) diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index da42c4916ce6..598a78ba894b 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -322,56 +322,6 @@ struct thin_c { /*----------------------------------------------------------------*/ -/** - * __blkdev_issue_discard_async - queue a discard with async completion - * @bdev: blockdev to issue discard for - * @sector: start sector - * @nr_sects: number of sectors to discard - * @gfp_mask: memory allocation flags (for bio_alloc) - * @flags: BLKDEV_IFL_* flags to control behaviour - * @parent_bio: parent discard bio that all sub discards get chained to - * - * Description: - * Asynchronously issue a discard request for the sectors in question. - */ -static int __blkdev_issue_discard_async(struct block_device *bdev, sector_t sector, - sector_t nr_sects, gfp_t gfp_mask, unsigned long flags, - struct bio *parent_bio) -{ - struct request_queue *q = bdev_get_queue(bdev); - int type = REQ_WRITE | REQ_DISCARD; - struct bio *bio; - - if (!q || !nr_sects) - return -ENXIO; - - if (!blk_queue_discard(q)) - return -EOPNOTSUPP; - - if (flags & BLKDEV_DISCARD_SECURE) { - if (!blk_queue_secdiscard(q)) - return -EOPNOTSUPP; - type |= REQ_SECURE; - } - - /* - * Required bio_put occurs in bio_endio thanks to bio_chain below - */ - bio = bio_alloc(gfp_mask, 1); - if (!bio) - return -ENOMEM; - - bio_chain(bio, parent_bio); - - bio->bi_iter.bi_sector = sector; - bio->bi_bdev = bdev; - bio->bi_iter.bi_size = nr_sects << 9; - - submit_bio(type, bio); - - return 0; -} - static bool block_size_is_power_of_two(struct pool *pool) { return pool->sectors_per_block_shift >= 0; @@ -387,11 +337,23 @@ static sector_t block_to_sectors(struct pool *pool, dm_block_t b) static int issue_discard(struct thin_c *tc, dm_block_t data_b, dm_block_t data_e, struct bio *parent_bio) { + int type = REQ_WRITE | REQ_DISCARD; sector_t s = block_to_sectors(tc->pool, data_b); sector_t len = block_to_sectors(tc->pool, data_e - data_b); + struct bio *bio = NULL; + struct blk_plug plug; + int ret; + + blk_start_plug(&plug); + ret = __blkdev_issue_discard(tc->pool_dev->bdev, s, len, + GFP_NOWAIT, type, &bio); + if (!ret && bio) { + bio_chain(bio, parent_bio); + submit_bio(type, bio); + } + blk_finish_plug(&plug); - return __blkdev_issue_discard_async(tc->pool_dev->bdev, s, len, - GFP_NOWAIT, 0, parent_bio); + return ret; } /*----------------------------------------------------------------*/ @@ -1543,11 +1505,11 @@ static void break_up_discard_bio(struct thin_c *tc, dm_block_t begin, dm_block_t /* * The parent bio must not complete before sub discard bios are - * chained to it (see __blkdev_issue_discard_async's bio_chain)! + * chained to it (see issue_discard's bio_chain)! * * This per-mapping bi_remaining increment is paired with * the implicit decrement that occurs via bio_endio() in - * process_prepared_discard_{passdown,no_passdown}. + * process_prepared_discard_passdown(). */ bio_inc_remaining(bio); if (!dm_deferred_set_add_work(pool->all_io_ds, &m->list)) -- 2.20.1