Commit 1e9290ca authored by Jens Axboe's avatar Jens Axboe Committed by Greg Kroah-Hartman

block: break discard submissions into the user defined size

[ Upstream commit af097f5d ]

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 <>
Reviewed-by: default avatarOmar Sandoval <>
Signed-off-by: default avatarJens Axboe <>
Signed-off-by: default avatarSasha Levin <>
parent 592f5569
......@@ -59,10 +59,16 @@ 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,
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.
Markdown is supported
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment