From bef13315e990fd3d3fb4c39013aefd53f06c3657 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 13 Jan 2017 15:18:16 -0700 Subject: [PATCH] block: don't try to discard from __blkdev_issue_zeroout Discard can return -EIO asynchronously if the alignment for the request isn't suitable for the driver, which makes a proper fallback to other methods in __blkdev_issue_zeroout impossible. Thus only issue a sync discard from blkdev_issue_zeroout an don't try discard at all from __blkdev_issue_zeroout as a non-invasive workaround. One more reason why abusing discard for zeroing must die.. Signed-off-by: Christoph Hellwig Reported-by: Eryu Guan Fixes: e73c23ff ("block: add async variant of blkdev_issue_zeroout") Signed-off-by: Jens Axboe --- block/blk-lib.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/block/blk-lib.c b/block/blk-lib.c index ed89c8f4b2a0..f8c82a9b4012 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -301,13 +301,6 @@ int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, if ((sector | nr_sects) & bs_mask) return -EINVAL; - if (discard) { - ret = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, - BLKDEV_DISCARD_ZERO, biop); - if (ret == 0 || (ret && ret != -EOPNOTSUPP)) - goto out; - } - ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask, biop); if (ret == 0 || (ret && ret != -EOPNOTSUPP)) @@ -370,6 +363,12 @@ int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, struct bio *bio = NULL; struct blk_plug plug; + if (discard) { + if (!blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, + BLKDEV_DISCARD_ZERO)) + return 0; + } + blk_start_plug(&plug); ret = __blkdev_issue_zeroout(bdev, sector, nr_sects, gfp_mask, &bio, discard); -- 2.39.5