[dm-devel] [PATCH 2/2] scsi : fixing the new host byte settings (DID_TARGET_FAILURE and DID_NEXUS_FAILURE)

[Moger, Babu]

This patch fixes the host byte settings DID_TARGET_FAILURE and DID_NEXUS_FAILURE.

The function __scsi_error_from_host_byte,  tries to reset the host byte to DID_OK. But that

does not happen because of the OR operation.



Here is the flow.

scsi_softirq_done-> scsi_decide_disposition -> __scsi_error_from_host_byte



Let's take an example with DID_NEXUS_FAILURE. In scsi_decide_disposition, result will be set as

DID_NEXUS_FAILURE (=0x11). Then in __scsi_error_from_host_byte, when we do OR with

DID_OK.  Purpose is to reset it back to DID_OK. But that does not happen.  This patch fixes this issue.



Signed-off-by: Babu Moger <babu.moger at netapp.com>

---

diff -uprN -X linux-3.3-rc1/Documentation/dontdiff linux-3.3-rc1//drivers/scsi/scsi_error.c linux-3.3-rc1-new//drivers/scsi/scsi_error.c
--- linux-3.3-rc1//drivers/scsi/scsi_error.c    2012-01-19 17:04:48.000000000 -0600
+++ linux-3.3-rc1-new//drivers/scsi/scsi_error.c      2012-01-23 11:55:26.000000000 -0600
@@ -1540,7 +1540,7 @@ int scsi_decide_disposition(struct scsi_
                   * Need to modify host byte to signal a
                   * permanent target failure
                   */
-                 scmd->result |= (DID_TARGET_FAILURE << 16);
+                 set_host_byte(scmd, DID_TARGET_FAILURE);
                  rtn = SUCCESS;
            }
            /* if rtn == FAILED, we have no sense information;
@@ -1560,7 +1560,7 @@ int scsi_decide_disposition(struct scsi_
      case RESERVATION_CONFLICT:
            sdev_printk(KERN_INFO, scmd->device,
                      "reservation conflict\n");
-           scmd->result |= (DID_NEXUS_FAILURE << 16);
+           set_host_byte(scmd, DID_NEXUS_FAILURE);
            return SUCCESS; /* causes immediate i/o error */
      default:
            return FAILED;
diff -uprN -X linux-3.3-rc1/Documentation/dontdiff linux-3.3-rc1//drivers/scsi/scsi_lib.c linux-3.3-rc1-new//drivers/scsi/scsi_lib.c
--- linux-3.3-rc1//drivers/scsi/scsi_lib.c      2012-01-19 17:04:48.000000000 -0600
+++ linux-3.3-rc1-new//drivers/scsi/scsi_lib.c  2012-01-23 11:50:25.000000000 -0600
@@ -682,11 +682,11 @@ static int __scsi_error_from_host_byte(s
            error = -ENOLINK;
            break;
      case DID_TARGET_FAILURE:
-           cmd->result |= (DID_OK << 16);
+           set_host_byte(cmd, DID_OK);
            error = -EREMOTEIO;
            break;
      case DID_NEXUS_FAILURE:
-           cmd->result |= (DID_OK << 16);
+           set_host_byte(cmd, DID_OK);
            error = -EBADE;
            break;
      default:







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