diff mbox

[V2,2/3] block/loop: use FALLOC_FL_ZERO_RANGE for REQ_OP_WRITE_ZEROES

Message ID 4bedc1416a9cfbb4547cc0fb4c67e77462f407f1.1504742003.git.shli@fb.com (mailing list archive)
State New, archived
Headers show

Commit Message

Shaohua Li Sept. 7, 2017, 12:13 a.m. UTC
From: Shaohua Li <shli@fb.com>

REQ_OP_WRITE_ZEROES really means zero the data. And in blkdev_fallocate,
FALLOC_FL_ZERO_RANGE will retry but FALLOC_FL_PUNCH_HOLE not, even loop
request doesn't have BLKDEV_ZERO_NOFALLBACK set.

Signed-off-by: Shaohua Li <shli@fb.com>
---
 drivers/block/loop.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Ming Lei Sept. 7, 2017, 9:05 a.m. UTC | #1
On Thu, Sep 7, 2017 at 8:13 AM, Shaohua Li <shli@kernel.org> wrote:
> From: Shaohua Li <shli@fb.com>
>
> REQ_OP_WRITE_ZEROES really means zero the data. And in blkdev_fallocate,
> FALLOC_FL_ZERO_RANGE will retry but FALLOC_FL_PUNCH_HOLE not, even loop
> request doesn't have BLKDEV_ZERO_NOFALLBACK set.
>
> Signed-off-by: Shaohua Li <shli@fb.com>
> ---
>  drivers/block/loop.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/block/loop.c b/drivers/block/loop.c
> index 715b762..8934e25 100644
> --- a/drivers/block/loop.c
> +++ b/drivers/block/loop.c
> @@ -426,6 +426,9 @@ static int lo_discard(struct loop_device *lo, struct request *rq, loff_t pos)
>         int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
>         int ret;
>
> +       if (req_op(rq) == REQ_OP_WRITE_ZEROES)
> +               mode = FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE;
> +
>         if ((!file->f_op->fallocate) || lo->lo_encrypt_key_size) {
>                 ret = -EOPNOTSUPP;
>                 goto out;
> --
> 2.9.5
>

Looks fine,

      Reviewed-by: Ming Lei <ming.lei@redhat.com>
diff mbox

Patch

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 715b762..8934e25 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -426,6 +426,9 @@  static int lo_discard(struct loop_device *lo, struct request *rq, loff_t pos)
 	int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
 	int ret;
 
+	if (req_op(rq) == REQ_OP_WRITE_ZEROES)
+		mode = FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE;
+
 	if ((!file->f_op->fallocate) || lo->lo_encrypt_key_size) {
 		ret = -EOPNOTSUPP;
 		goto out;