nvmet: use NVME_IDENTIFY_DATA_SIZE

Use NVME_IDENTIFY_DATA_SIZE define instead of hard coding the magic
4096 value.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.com>
[hch: converted three more users]
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/host/lightnvm.c

@@ -242,7 +242,7 @@ static inline void _nvme_nvm_check_size(void)
 	BUILD_BUG_ON(sizeof(struct nvme_nvm_erase_blk) != 64);
 	BUILD_BUG_ON(sizeof(struct nvme_nvm_id_group) != 960);
 	BUILD_BUG_ON(sizeof(struct nvme_nvm_addr_format) != 16);
-	BUILD_BUG_ON(sizeof(struct nvme_nvm_id) != 4096);
+	BUILD_BUG_ON(sizeof(struct nvme_nvm_id) != NVME_IDENTIFY_DATA_SIZE);
 	BUILD_BUG_ON(sizeof(struct nvme_nvm_bb_tbl) != 64);
 }
 

drivers/nvme/host/pci.c

@@ -183,8 +183,8 @@ static inline void _nvme_check_size(void)
 	BUILD_BUG_ON(sizeof(struct nvme_format_cmd) != 64);
 	BUILD_BUG_ON(sizeof(struct nvme_abort_cmd) != 64);
 	BUILD_BUG_ON(sizeof(struct nvme_command) != 64);
-	BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != 4096);
-	BUILD_BUG_ON(sizeof(struct nvme_id_ns) != 4096);
+	BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != NVME_IDENTIFY_DATA_SIZE);
+	BUILD_BUG_ON(sizeof(struct nvme_id_ns) != NVME_IDENTIFY_DATA_SIZE);
 	BUILD_BUG_ON(sizeof(struct nvme_lba_range_type) != 64);
 	BUILD_BUG_ON(sizeof(struct nvme_smart_log) != 512);
 	BUILD_BUG_ON(sizeof(struct nvme_dbbuf) != 64);

drivers/nvme/target/admin-cmd.c

@@ -336,7 +336,7 @@ out:
 
 static void nvmet_execute_identify_nslist(struct nvmet_req *req)
 {
-	static const int buf_size = 4096;
+	static const int buf_size = NVME_IDENTIFY_DATA_SIZE;
 	struct nvmet_ctrl *ctrl = req->sq->ctrl;
 	struct nvmet_ns *ns;
 	u32 min_nsid = le32_to_cpu(req->cmd->identify.nsid);
@@ -504,7 +504,7 @@ u16 nvmet_parse_admin_cmd(struct nvmet_req *req)
 		}
 		break;
 	case nvme_admin_identify:
-		req->data_len = 4096;
+		req->data_len = NVME_IDENTIFY_DATA_SIZE;
 		switch (cmd->identify.cns) {
 		case NVME_ID_CNS_NS:
 			req->execute = nvmet_execute_identify_ns;

drivers/nvme/target/discovery.c

@@ -185,7 +185,7 @@ u16 nvmet_parse_discovery_cmd(struct nvmet_req *req)
 		return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
 		}
 	case nvme_admin_identify:
-		req->data_len = 4096;
+		req->data_len = NVME_IDENTIFY_DATA_SIZE;
 		switch (cmd->identify.cns) {
 		case NVME_ID_CNS_CTRL:
 			req->execute =

include/linux/nvme.h

@@ -665,6 +665,8 @@ struct nvme_identify {
 	__u32			rsvd11[5];
 };
 
+#define NVME_IDENTIFY_DATA_SIZE 4096
+
 struct nvme_features {
 	__u8			opcode;
 	__u8			flags;