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 <[email protected]> Reported-by: Eryu Guan <[email protected]> Fixes: e73c23ff ("block: add async variant of blkdev_issue_zeroout") --- 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 ed89c8f..f8c82a9 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); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
