Re: [PATCH v2 3/7] sd: Cleanup sd_done sense data handling

[Christoph Hellwig]

I would just use a switch and kill the op and unmap variables entirely,
e.g. something like the patch below:

---
From: Christoph Hellwig <h...@lst.de>
Subject: sd: Cleanup sd_done sense data handling

Use a switch for the sense key, and remove two pointless variables
that are only used once.

Signed-off-by: Christoph Hellwig <h...@lst.de>
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 8cf34a8e3eea..eec695107c99 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1866,8 +1866,6 @@ static int sd_done(struct scsi_cmnd *SCpnt)
        struct request *req = SCpnt->request;
        int sense_valid = 0;
        int sense_deferred = 0;
-       unsigned char op = SCpnt->cmnd[0];
-       unsigned char unmap = SCpnt->cmnd[1] & 8;
 
        switch (req_op(req)) {
        case REQ_OP_DISCARD:
@@ -1941,19 +1939,21 @@ static int sd_done(struct scsi_cmnd *SCpnt)
                        good_bytes = sd_completed_bytes(SCpnt);
                break;
        case ILLEGAL_REQUEST:
-               if (sshdr.asc == 0x10)  /* DIX: Host detected corruption */
+               switch (sshdr.asc) {
+               case 0x10:      /* DIX: Host detected corruption */
                        good_bytes = sd_completed_bytes(SCpnt);
-               /* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */
-               if (sshdr.asc == 0x20 || sshdr.asc == 0x24) {
-                       switch (op) {
+                       break;
+               case 0x20:      /* INVALID COMMAND OPCODE */
+               case 0x24:      /* INVALID FIELD IN CDB */
+                       switch (SCpnt->cmnd[0]) {
                        case UNMAP:
                                sd_config_discard(sdkp, SD_LBP_DISABLE);
                                break;
                        case WRITE_SAME_16:
                        case WRITE_SAME:
-                               if (unmap)
+                               if (SCpnt->cmnd[1] & 8) {
                                        sd_config_discard(sdkp, SD_LBP_DISABLE);
-                               else {
+                               } else {
                                        sdkp->device->no_write_same = 1;
                                        sd_config_write_same(sdkp);
 
@@ -1961,6 +1961,7 @@ static int sd_done(struct scsi_cmnd *SCpnt)
                                        req->__data_len = blk_rq_bytes(req);
                                        req->rq_flags |= RQF_QUIET;
                                }
+                               break;
                        }
                }
                break;