Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit af097f5d authored by Jens Axboe's avatar Jens Axboe
Browse files

block: break discard submissions into the user defined size 



Don't build discards bigger than what the user asked for, if the
user decided to limit the size by writing to 'discard_max_bytes'.

Reviewed-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: default avatarOmar Sandoval <osandov@fb.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent d3349b6b

block/blk-lib.c

+9 −3
Original line number Diff line number Diff line
@@ -62,10 +62,16 @@ int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, 
		unsigned int req_sects;

		sector_t end_sect, tmp;



		/* Make sure bi_size doesn't overflow */

		req_sects = min_t(sector_t, nr_sects, UINT_MAX >> 9);

		/*

		 * Issue in chunks of the user defined max discard setting,

		 * ensuring that bi_size doesn't overflow

		 */

		req_sects = min_t(sector_t, nr_sects,

					q->limits.max_discard_sectors);

		if (req_sects > UINT_MAX >> 9)

			req_sects = UINT_MAX >> 9;



		/**

		/*

		 * If splitting a request, and the next starting sector would be

		 * misaligned, stop the discard at the previous aligned sector.

		 */