[PATCH 04/10] nvmet: set WZDS and DRB if device supports BLK_FEAT_WRITE_ZEROES_UNMAP

Zhang Yi
2025-06-04T02:21:53Z

From: Zhang Yi <yi.zhang@huawei.com>

Set WZDS and DRB bit to the namespace dlfeat if the underlying block
device supports BLK_FEAT_WRITE_ZEROES_UNMAP, make the nvme target
device supports unmaped write zeroes command.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
drivers/nvme/target/io-cmd-bdev.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c
index 83be0657e6df..052da6174548 100644
--- a/drivers/nvme/target/io-cmd-bdev.c
+++ b/drivers/nvme/target/io-cmd-bdev.c
@@ -46,6 +46,10 @@ void nvmet_bdev_set_limits(struct block_device *bdev, struct nvme_id_ns *id)
id->npda = id->npdg;
/* NOWS = Namespace Optimal Write Size */
id->nows = to0based(bdev_io_opt(bdev) / bdev_logical_block_size(bdev));
+
+ /* Set WZDS and DRB if device supports unmapped write zeroes */
+ if (bdev_write_zeroes_unmap(bdev))
+ id->dlfeat = (1 << 3) | 0x1;
}

void nvmet_bdev_ns_disable(struct nvmet_ns *ns)
--
2.46.1