block: don't try Write Same from __blkdev_issue_zeroout

Write Same can return an error asynchronously if it turns out the underlying SCSI device does not support Write Same, which makes a proper fallback to other methods in __blkdev_issue_zeroout impossible. Thus only issue a Write Same from blkdev_issue_zeroout an don't try it at all from __blkdev_issue_zeroout as a non-invasive workaround. Signed-off-by: Christoph Hellwig <[email protected]> Reported-by: Junichi Nomura <[email protected]> Fixes: e73c23f ("block: add async variant of blkdev_issue_zeroout") Tested-by: Junichi Nomura <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
CamonZ · Feb 6, 2017 · eeeefd4 · eeeefd4
1 parent c14024d
commit eeeefd4
Showing 1 changed file with 4 additions and 5 deletions.
diff --git a/block/blk-lib.c b/block/blk-lib.c
@@ -306,11 +306,6 @@ int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
 	if (ret == 0 || (ret && ret != -EOPNOTSUPP))
 		goto out;
 
-	ret = __blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask,
-			ZERO_PAGE(0), biop);
-	if (ret == 0 || (ret && ret != -EOPNOTSUPP))
-		goto out;
-
 	ret = 0;
 	while (nr_sects != 0) {
 		bio = next_bio(bio, min(nr_sects, (sector_t)BIO_MAX_PAGES),
@@ -369,6 +364,10 @@ int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
 			return 0;
 	}
 
+	if (!blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask,
+			ZERO_PAGE(0)))
+		return 0;
+
 	blk_start_plug(&plug);
 	ret = __blkdev_issue_zeroout(bdev, sector, nr_sects, gfp_mask,
 			&bio, discard);