From: Shaohua Li <shli@xxxxxx>
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@xxxxxx>
---
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
