From 10d1f9e2ccfff40665a00ea0e0a0d11e54c9cbb1 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 15 Jul 2010 10:49:31 -0600 Subject: block: fix problem with sending down discard that isn't of correct granularity If the queue doesn't have a limit set, or it just set UINT_MAX like we default to, we coud be sending down a discard request that isn't of the correct granularity if the block size is > 512b. Fix this by adjusting max_discard_sectors down to the proper alignment. Signed-off-by: Jens Axboe --- block/blk-lib.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'block/blk-lib.c') diff --git a/block/blk-lib.c b/block/blk-lib.c index e16185b0d8e1..5d793e143f3c 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -41,6 +41,7 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, struct request_queue *q = bdev_get_queue(bdev); int type = flags & BLKDEV_IFL_BARRIER ? DISCARD_BARRIER : DISCARD_NOBARRIER; + unsigned int max_discard_sectors; struct bio *bio; int ret = 0; @@ -50,10 +51,18 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, if (!blk_queue_discard(q)) return -EOPNOTSUPP; - while (nr_sects && !ret) { - unsigned int max_discard_sectors = - min(q->limits.max_discard_sectors, UINT_MAX >> 9); + /* + * Ensure that max_discard_sectors is of the proper + * granularity + */ + max_discard_sectors = min(q->limits.max_discard_sectors, UINT_MAX >> 9); + if (q->limits.discard_granularity) { + unsigned int disc_sects = q->limits.discard_granularity >> 9; + max_discard_sectors &= ~(disc_sects - 1); + } + + while (nr_sects && !ret) { bio = bio_alloc(gfp_mask, 1); if (!bio) { ret = -ENOMEM; -- cgit v1.2.3-70-g09d2