[PATCH 3/3 v2] nvmet: add rotational support

[Matias Bjørling]

From: Keith Busch <kbusch at kernel.org>

Rotational block devices can be detected in NVMe through the rotational
attribute in the independent namespace identify data structure.

Extend nvmet with support for the independent namespace identify data
structure and expose the rotational support of the backend device.

Signed-off-by: Keith Busch <kbusch at kernel.org>
---
 drivers/nvme/target/admin-cmd.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index f7e1156ac7ec..f08f1226c897 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -675,6 +675,35 @@ static void nvmet_execute_identify_ctrl_nvm(struct nvmet_req *req)
 		   nvmet_zero_sgl(req, 0, sizeof(struct nvme_id_ctrl_nvm)));
 }
 
+static void nvmet_execute_id_cs_indep(struct nvmet_req *req)
+{
+	struct nvme_id_ns_cs_indep *id;
+	u16 status;
+
+	status = nvmet_req_find_ns(req);
+	if (status)
+		goto out;
+
+	id = kzalloc(sizeof(*id), GFP_KERNEL);
+	if (!id) {
+		status = NVME_SC_INTERNAL;
+		goto out;
+	}
+
+	id->nstat = NVME_NSTAT_NRDY;
+	id->anagrpid = req->ns->anagrpid;
+	id->nmic = NVME_NS_NMIC_SHARED;
+	if (req->ns->readonly)
+		id->nsattr |= NVME_NS_ATTR_RO;
+	if (req->ns->bdev && !bdev_nonrot(req->ns->bdev))
+		id->nsfeat |= NVME_NS_ROTATIONAL;
+
+	status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id));
+	kfree(id);
+out:
+	nvmet_req_complete(req, status);
+}
+
 static void nvmet_execute_identify(struct nvmet_req *req)
 {
 	if (!nvmet_check_transfer_len(req, NVME_IDENTIFY_DATA_SIZE))
@@ -719,6 +748,9 @@ static void nvmet_execute_identify(struct nvmet_req *req)
 			break;
 		}
 		break;
+	case NVME_ID_CNS_NS_CS_INDEP:
+		nvmet_execute_id_cs_indep(req);
+		return;
 	}
 
 	pr_debug("unhandled identify cns %d on qid %d\n",
-- 
2.46.0