Commit 10d1f9e2 authored by Jens Axboe's avatar Jens Axboe
Browse files

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: default avatarJens Axboe <jaxboe@fusionio.com>
parent f10d9f61

block/blk-lib.c

+12 −3
Original line number Diff line number Diff line
@@ -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;

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