[PATCHv4 13/13] nvmet: report ns's vwc not present

[Keith Busch]

From: Guixin Liu <kanie at linux.alibaba.com>

Currently, we report that controller has vwc even though the ns may
not have vwc. Report ns's vwc not present when not buffered_io or
backdev doesn't have vwc.

Signed-off-by: Guixin Liu <kanie at linux.alibaba.com>
Signed-off-by: Keith Busch <kbusch at kernel.org>
---
 drivers/nvme/target/admin-cmd.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index 516af7b419189..f688d7fdf7d67 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -915,6 +915,9 @@ static void nvmet_execute_id_cs_indep(struct nvmet_req *req)
 		id->nsattr |= NVME_NS_ATTR_RO;
 	if (req->ns->bdev && !bdev_nonrot(req->ns->bdev))
 		id->nsfeat |= NVME_NS_ROTATIONAL;
+	if ((req->ns->file && !req->ns->buffered_io) ||
+	    (req->ns->bdev && !bdev_write_cache(req->ns->bdev)))
+		id->nsfeat |= NVME_NS_VWC_NOT_PRESENT;
 
 	status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id));
 	kfree(id);
-- 
2.43.5