Commit 1adfc5e4 authored by Ming Lei's avatar Ming Lei Committed by Jens Axboe
Browse files

block: make sure discard bio is aligned with logical block size 



Obviously the created discard bio has to be aligned with logical block size.

This patch introduces the helper of bio_allowed_max_sectors() for
this purpose.

Cc: stable@vger.kernel.org
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Xiao Ni <xni@redhat.com>
Cc: Mariusz Dabrowski <mariusz.dabrowski@intel.com>
Fixes: 744889b7 ("block: don't deal with discard limit in blkdev_issue_discard()")
Fixes: a22c4d7e ("block: re-add discard_granularity and alignment checks")
Reported-by: default avatarRui Salvaterra <rsalvaterra@gmail.com>
Tested-by: default avatarRui Salvaterra <rsalvaterra@gmail.com>
Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent d39aa497

block/blk-lib.c

+1 −2
Original line number Diff line number Diff line
@@ -57,8 +57,7 @@ int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, 


		if (!req_sects)

			goto fail;

		if (req_sects > UINT_MAX >> 9)

			req_sects = UINT_MAX >> 9;

		req_sects = min(req_sects, bio_allowed_max_sectors(q));



		end_sect = sector + req_sects;

block/blk-merge.c

+2 −1
Original line number Diff line number Diff line
@@ -90,7 +90,8 @@ static struct bio *blk_bio_discard_split(struct request_queue *q, 
	/* Zero-sector (unknown) and one-sector granularities are the same.  */

	granularity = max(q->limits.discard_granularity >> 9, 1U);



	max_discard_sectors = min(q->limits.max_discard_sectors, UINT_MAX >> 9);

	max_discard_sectors = min(q->limits.max_discard_sectors,

			bio_allowed_max_sectors(q));

	max_discard_sectors -= max_discard_sectors % granularity;



	if (unlikely(!max_discard_sectors)) {

block/blk.h

+10 −0
Original line number Diff line number Diff line
@@ -395,6 +395,16 @@ static inline unsigned long blk_rq_deadline(struct request *rq) 
	return rq->__deadline & ~0x1UL;

}



/*

 * The max size one bio can handle is UINT_MAX becasue bvec_iter.bi_size

 * is defined as 'unsigned int', meantime it has to aligned to with logical

 * block size which is the minimum accepted unit by hardware.

 */

static inline unsigned int bio_allowed_max_sectors(struct request_queue *q)

{

	return round_down(UINT_MAX, queue_logical_block_size(q)) >> 9;

}



/*

 * Internal io_context interface

 */

CRA Git | Maintained and supported by SUSTech CRA and CCSE