[RFC PATCH v4 04/11] nvmet: set WZDS and DRB if device supports BLK_FEAT_WRITE_ZEROES_UNMAP

[Zhang Yi]

From: Zhang Yi <yi.zh...@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.zh...@huawei.com>
---
 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