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 <jaxboe@fusionio.com>
This commit is contained in:
Jens Axboe 2010-07-15 10:49:31 -06:00
parent f10d9f617a
commit 10d1f9e2cc

View File

@ -41,6 +41,7 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
struct request_queue *q = bdev_get_queue(bdev); struct request_queue *q = bdev_get_queue(bdev);
int type = flags & BLKDEV_IFL_BARRIER ? int type = flags & BLKDEV_IFL_BARRIER ?
DISCARD_BARRIER : DISCARD_NOBARRIER; DISCARD_BARRIER : DISCARD_NOBARRIER;
unsigned int max_discard_sectors;
struct bio *bio; struct bio *bio;
int ret = 0; int ret = 0;
@ -50,10 +51,18 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
if (!blk_queue_discard(q)) if (!blk_queue_discard(q))
return -EOPNOTSUPP; return -EOPNOTSUPP;
while (nr_sects && !ret) { /*
unsigned int max_discard_sectors = * Ensure that max_discard_sectors is of the proper
min(q->limits.max_discard_sectors, UINT_MAX >> 9); * 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); bio = bio_alloc(gfp_mask, 1);
if (!bio) { if (!bio) {
ret = -ENOMEM; ret = -ENOMEM;