It's identical to discard as hole punches will always leave us with zeroes on reads.
Signed-off-by: Christoph Hellwig <h...@lst.de> --- 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