scsi: ufs: Make ufshcd_add_command_trace() easier to read

Since the lrbp->cmd expression occurs multiple times, introduce a new local
variable to hold that pointer. This patch does not change any
functionality.

Cc: Bean Huo <beanhuo@micron.com>
Cc: Can Guo <cang@codeaurora.org>
Cc: Avri Altman <avri.altman@wdc.com>
Cc: Stanley Chu <stanley.chu@mediatek.com>
Cc: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20191224220248.30138-3-bvanassche@acm.orgReviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Can Guo <cang@codeaurora.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ufs/ufshcd.c

@@ -327,27 +327,27 @@ static void ufshcd_add_command_trace(struct ufs_hba *hba,
 	u8 opcode = 0;
 	u32 intr, doorbell;
 	struct ufshcd_lrb *lrbp = &hba->lrb[tag];
+	struct scsi_cmnd *cmd = lrbp->cmd;
 	int transfer_len = -1;
 
 	if (!trace_ufshcd_command_enabled()) {
 		/* trace UPIU W/O tracing command */
-		if (lrbp->cmd)
+		if (cmd)
 			ufshcd_add_cmd_upiu_trace(hba, tag, str);
 		return;
 	}
 
-	if (lrbp->cmd) { /* data phase exists */
+	if (cmd) { /* data phase exists */
 		/* trace UPIU also */
 		ufshcd_add_cmd_upiu_trace(hba, tag, str);
-		opcode = (u8)(*lrbp->cmd->cmnd);
+		opcode = cmd->cmnd[0];
 		if ((opcode == READ_10) || (opcode == WRITE_10)) {
 			/*
 			 * Currently we only fully trace read(10) and write(10)
 			 * commands
 			 */
-			if (lrbp->cmd->request && lrbp->cmd->request->bio)
-				lba =
-				  lrbp->cmd->request->bio->bi_iter.bi_sector;
+			if (cmd->request && cmd->request->bio)
+				lba = cmd->request->bio->bi_iter.bi_sector;
 			transfer_len = be32_to_cpu(
 				lrbp->ucd_req_ptr->sc.exp_data_transfer_len);
 		}