scsi: Add ALUA state change UA handling

Log the ALUA state change unit attention correctly with
the message log and emit an event to allow user-space
tools to react to it.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index cfadcce..d7d2806 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -421,6 +421,10 @@
 			evt_type = SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED;
 			sdev_printk(KERN_WARNING, sdev,
 				    "Mode parameters changed");
+		} else if (sshdr->asc == 0x2a && sshdr->ascq == 0x06) {
+			evt_type = SDEV_EVT_ALUA_STATE_CHANGE_REPORTED;
+			sdev_printk(KERN_WARNING, sdev,
+				    "Asymmetric access state changed");
 		} else if (sshdr->asc == 0x2a && sshdr->ascq == 0x09) {
 			evt_type = SDEV_EVT_CAPACITY_CHANGE_REPORTED;
 			sdev_printk(KERN_WARNING, sdev,
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index dffa91c..882864f 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2712,6 +2712,9 @@
 	case SDEV_EVT_LUN_CHANGE_REPORTED:
 		envp[idx++] = "SDEV_UA=REPORTED_LUNS_DATA_HAS_CHANGED";
 		break;
+	case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED:
+		envp[idx++] = "SDEV_UA=ASYMMETRIC_ACCESS_STATE_CHANGED";
+		break;
 	default:
 		/* do nothing */
 		break;
@@ -2815,6 +2818,7 @@
 	case SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED:
 	case SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED:
 	case SDEV_EVT_LUN_CHANGE_REPORTED:
+	case SDEV_EVT_ALUA_STATE_CHANGE_REPORTED:
 	default:
 		/* do nothing */
 		break;
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index ae84b22..50c2a36 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -57,9 +57,10 @@
 	SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED,	/* 38 07  UA reported */
 	SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED,	/* 2A 01  UA reported */
 	SDEV_EVT_LUN_CHANGE_REPORTED,			/* 3F 0E  UA reported */
+	SDEV_EVT_ALUA_STATE_CHANGE_REPORTED,		/* 2A 06  UA reported */
 
 	SDEV_EVT_FIRST		= SDEV_EVT_MEDIA_CHANGE,
-	SDEV_EVT_LAST		= SDEV_EVT_LUN_CHANGE_REPORTED,
+	SDEV_EVT_LAST		= SDEV_EVT_ALUA_STATE_CHANGE_REPORTED,
 
 	SDEV_EVT_MAXBITS	= SDEV_EVT_LAST + 1
 };