Now that we have REQ_OP_WRITE_ZEROES implemented for all devices that
support efficient zeroing of devices we can remove the call to
blkdev_issue_discard. This means we only have two ways of zeroing left
and can simply the code.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
block/blk-lib.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/block/blk-lib.c b/block/blk-lib.c
index 33c5bf373b7f..153ca59393a7 100644
--- a/block/blk-lib.c
+++ b/block/blk-lib.c
@@ -279,6 +279,11 @@ static int __blkdev_issue_write_zeroes(struct block_device *bdev,
* Zero-fill a block range, either using hardware offload or by explicitly
* writing zeroes to the device.
*
+ * Note that this function may fail with -EOPNOTSUPP if the driver supports
+ * efficient zeroing operation, but the device capabilities can only be
+ * discovered by trial and error. In this case the caller should call the
+ * function again, and it will use the fallback path.
+ *
* If a device is using logical block provisioning, the underlying space will
* only be release if %flags contains BLKDEV_ZERO_UNMAP.
*
@@ -349,12 +354,6 @@ int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
struct bio *bio = NULL;
struct blk_plug plug;
- if (flags & BLKDEV_ZERO_UNMAP) {
- 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, flags);
--
2.11.0
--
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