nvme: define the remaining used sgls constants

This provides a little more context when reading the code than hardcoded
magic numbers.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

Author: keithbusch

drivers/nvme/host/nvme.h

@@ -1123,7 +1123,8 @@ static inline void nvme_start_request(struct request *rq)
 
 static inline bool nvme_ctrl_sgl_supported(struct nvme_ctrl *ctrl)
 {
-	return ctrl->sgls & ((1 << 0) | (1 << 1));
+	return ctrl->sgls & (NVME_CTRL_SGLS_BYTE_ALIGNED |
+			     NVME_CTRL_SGLS_DWORD_ALIGNED);
 }
 
 static inline bool nvme_ctrl_meta_sgl_supported(struct nvme_ctrl *ctrl)

drivers/nvme/host/rdma.c

@@ -1019,7 +1019,7 @@ static int nvme_rdma_setup_ctrl(struct nvme_rdma_ctrl *ctrl, bool new)
 		goto destroy_admin;
 	}
 
-	if (!(ctrl->ctrl.sgls & (1 << 2))) {
+	if (!(ctrl->ctrl.sgls & NVME_CTRL_SGLS_KSDBDS)) {
 		ret = -EOPNOTSUPP;
 		dev_err(ctrl->ctrl.device,
 			"Mandatory keyed sgls are not supported!\n");
@@ -1051,7 +1051,7 @@ static int nvme_rdma_setup_ctrl(struct nvme_rdma_ctrl *ctrl, bool new)
 		ctrl->ctrl.sqsize = ctrl->ctrl.maxcmd - 1;
 	}
 
-	if (ctrl->ctrl.sgls & (1 << 20))
+	if (ctrl->ctrl.sgls & NVME_CTRL_SGLS_SAOS)
 		ctrl->use_inline_data = true;
 
 	if (ctrl->ctrl.queue_count > 1) {

drivers/nvme/target/admin-cmd.c

@@ -601,11 +601,12 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
 	id->awun = 0;
 	id->awupf = 0;
 
-	id->sgls = cpu_to_le32(1 << 0);	/* we always support SGLs */
+	/* we always support SGLs */
+	id->sgls = cpu_to_le32(NVME_CTRL_SGLS_BYTE_ALIGNED);
 	if (ctrl->ops->flags & NVMF_KEYED_SGLS)
-		id->sgls |= cpu_to_le32(1 << 2);
+		id->sgls |= cpu_to_le32(NVME_CTRL_SGLS_KSDBDS);
 	if (req->port->inline_data_size)
-		id->sgls |= cpu_to_le32(1 << 20);
+		id->sgls |= cpu_to_le32(NVME_CTRL_SGLS_SAOS);
 
 	strscpy(id->subnqn, ctrl->subsys->subsysnqn, sizeof(id->subnqn));
 

include/linux/nvme.h

@@ -389,7 +389,11 @@ enum {
 	NVME_CTRL_CTRATT_PREDICTABLE_LAT	= 1 << 5,
 	NVME_CTRL_CTRATT_NAMESPACE_GRANULARITY	= 1 << 7,
 	NVME_CTRL_CTRATT_UUID_LIST		= 1 << 9,
+	NVME_CTRL_SGLS_BYTE_ALIGNED             = 1,
+	NVME_CTRL_SGLS_DWORD_ALIGNED            = 2,
+	NVME_CTRL_SGLS_KSDBDS			= 1 << 2,
 	NVME_CTRL_SGLS_MSDS                     = 1 << 19,
+	NVME_CTRL_SGLS_SAOS                     = 1 << 20,
 };
 
 struct nvme_lbaf {