nvme: Use CNS as 8-bit field and avoid endianness conversion

This patch defines CNS field as 8-bit field and avoids cpu_to/from_le
conversions.
Also initialize nvme_command cns value explicitly to NVME_ID_CNS_NS
for readability (don't rely on the fact that NVME_ID_CNS_NS = 0).

Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index a68bf6954ead7a9d3ca5ee4f1b8b76cc1ad8f353..8b1be128b66ebdec97dbaaff127958cf4fb2d2ac 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -560,7 +560,7 @@ int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id)
 
        /* gcc-4.4.4 (at least) has issues with initializers and anon unions */
        c.identify.opcode = nvme_admin_identify;
-       c.identify.cns = cpu_to_le32(NVME_ID_CNS_CTRL);
+       c.identify.cns = NVME_ID_CNS_CTRL;
 
        *id = kmalloc(sizeof(struct nvme_id_ctrl), GFP_KERNEL);
        if (!*id)
@@ -578,7 +578,7 @@ static int nvme_identify_ns_list(struct nvme_ctrl *dev, unsigned nsid, __le32 *n
        struct nvme_command c = { };
 
        c.identify.opcode = nvme_admin_identify;
-       c.identify.cns = cpu_to_le32(NVME_ID_CNS_NS_ACTIVE_LIST);
+       c.identify.cns = NVME_ID_CNS_NS_ACTIVE_LIST;
        c.identify.nsid = cpu_to_le32(nsid);
        return nvme_submit_sync_cmd(dev->admin_q, &c, ns_list, 0x1000);
 }
@@ -592,6 +592,7 @@ int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
        /* gcc-4.4.4 (at least) has issues with initializers and anon unions */
        c.identify.opcode = nvme_admin_identify;
        c.identify.nsid = cpu_to_le32(nsid);
+       c.identify.cns = NVME_ID_CNS_NS;
 
        *id = kmalloc(sizeof(struct nvme_id_ns), GFP_KERNEL);
        if (!*id)

diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index 204e85efebab089b699c33e645d3a64707bfe018..94e524fea5687b8de8ebf68d6469676cae4fa08d 100644 (file)
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -509,7 +509,7 @@ int nvmet_parse_admin_cmd(struct nvmet_req *req)
                break;
        case nvme_admin_identify:
                req->data_len = 4096;
-               switch (le32_to_cpu(cmd->identify.cns)) {
+               switch (cmd->identify.cns) {
                case NVME_ID_CNS_NS:
                        req->execute = nvmet_execute_identify_ns;
                        return 0;

diff --git a/drivers/nvme/target/discovery.c b/drivers/nvme/target/discovery.c
index 12f39eea569f2fb33cec45884c188d0ad8ae2493..af8aabf0533504971bef38fbdd02c3943b805a5f 100644 (file)
--- a/drivers/nvme/target/discovery.c
+++ b/drivers/nvme/target/discovery.c
@@ -186,14 +186,14 @@ int nvmet_parse_discovery_cmd(struct nvmet_req *req)
                }
        case nvme_admin_identify:
                req->data_len = 4096;
-               switch (le32_to_cpu(cmd->identify.cns)) {
+               switch (cmd->identify.cns) {
                case NVME_ID_CNS_CTRL:
                        req->execute =
                                nvmet_execute_identify_disc_ctrl;
                        return 0;
                default:
                        pr_err("nvmet: unsupported identify cns %d\n",
-                               le32_to_cpu(cmd->identify.cns));
+                               cmd->identify.cns);
                        return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
                }
        default:

diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 0b676a02cf3e0899cb27c068bb6d3c1225a2506a..5b32521456d67491eb7bd88e72fb3756b9e1ff7e 100644 (file)
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -644,7 +644,9 @@ struct nvme_identify {
        __le32                  nsid;
        __u64                   rsvd2[2];
        union nvme_data_ptr     dptr;
-       __le32                  cns;
+       __u8                    cns;
+       __u8                    rsvd3;
+       __le16                  ctrlid;
        __u32                   rsvd11[5];
 };