It's identical to discard as hole punches will always leave us with
zeroes on reads.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/block/loop.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 0ecb6461ed81..265cd2e33ff0 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -528,6 +528,7 @@ static int do_req_filebacked(struct loop_device *lo, struct request *rq)
case REQ_OP_FLUSH:
return lo_req_flush(lo, rq);
case REQ_OP_DISCARD:
+ case REQ_OP_WRITE_ZEROES:
return lo_discard(lo, rq, pos);
case REQ_OP_WRITE:
if (lo->transfer)
@@ -826,6 +827,7 @@ static void loop_config_discard(struct loop_device *lo)
q->limits.discard_granularity = 0;
q->limits.discard_alignment = 0;
blk_queue_max_discard_sectors(q, 0);
+ blk_queue_max_write_zeroes_sectors(q, 0);
q->limits.discard_zeroes_data = 0;
queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
return;
@@ -834,6 +836,7 @@ static void loop_config_discard(struct loop_device *lo)
q->limits.discard_granularity = inode->i_sb->s_blocksize;
q->limits.discard_alignment = 0;
blk_queue_max_discard_sectors(q, UINT_MAX >> 9);
+ blk_queue_max_write_zeroes_sectors(q, UINT_MAX >> 9);
q->limits.discard_zeroes_data = 1;
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
}
@@ -1660,6 +1663,7 @@ static int loop_queue_rq(struct blk_mq_hw_ctx *hctx,
switch (req_op(cmd->rq)) {
case REQ_OP_FLUSH:
case REQ_OP_DISCARD:
+ case REQ_OP_WRITE_ZEROES:
cmd->use_aio = false;
break;
default:
--
2.11.0
