From 1e9290ca9d6fa96b69c4d6125f87dc77793179e1 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 8 May 2018 15:09:41 -0600 Subject: [PATCH] block: break discard submissions into the user defined size [ Upstream commit af097f5d199e2aa3ab3ef777f0716e487b8f7b08 ] 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: Darrick J. Wong Reviewed-by: Omar Sandoval Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- block/blk-lib.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/block/blk-lib.c b/block/blk-lib.c index 2bc544ce3d2e..53a45663e688 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -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, + 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. */ -- 2.20.1