diff mbox

[V3,2/3] block/loop: use FALLOC_FL_ZERO_RANGE for REQ_OP_WRITE_ZEROES

Message ID b2a8123d49958e882ea0fb0be6573adbf40be5f7.1507072136.git.shli@fb.com (mailing list archive)
State New, archived
Headers show

Commit Message

Shaohua Li Oct. 4, 2017, 2:52 p.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>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
---
 drivers/block/loop.c | 3 +++
 1 file changed, 3 insertions(+)
diff mbox

Patch

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 6aa739f..7269341 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;