bio_discard_limit() enforces discard boundaries within the range of 32-bit unsigned integers, resulting in unexpected discard cut boundaries. For example, max discard size = 1MiB, discard_granularity = 512B, then the discard lengths sent in the range [0,4G) are 1MiB, 1MiB... (1MiB-512). The next discard offset from 4G is [4G-512, 4G-512+1MiB). The discard of the 4G offset boundary does not comply with the optimal 1MiB size. Signed-off-by: Li Feng <fengli@xxxxxxxxxx> --- block/blk-lib.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/blk-lib.c b/block/blk-lib.c index e59c3069e835..ec95508c3593 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -32,7 +32,7 @@ static sector_t bio_discard_limit(struct block_device *bdev, sector_t sector) * Align the bio size to the discard granularity to make splitting the bio * at discard granularity boundaries easier in the driver if needed. */ - return round_down(UINT_MAX, discard_granularity) >> SECTOR_SHIFT; + return round_down(ULONG_MAX, discard_granularity) >> SECTOR_SHIFT; } int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, -- 2.41.0
