[dm-devel] [PATCH] multipath-tools: service mode changes for RDAC storage

[Moger, Babu]

This patch handles the recent changes in NetApp RDAC storage firmware to report service mode. Firmware changed the inquiry page 0xc9 to report service mode. Purpose this change is to avoid DMMP going into infinite loop of switching back and forth between controllers when a controller is placed in service mode. This fixes the problem and reports the path as failed if the controller is placed in service mode.
 
Signed-off-by: Babu Moger <babu.moger at netapp.com>
Reviewed-by: Yanling Qi <yanling.qi at netapp.com>
Reviewed-by: Somasundaram Krishnasamy <Somasundaram.Krishnasamy at netapp.com>

---
--- multipath-tools-0.4.8/libmultipath/checkers/rdac.c.orig	2011-07-06 16:37:43.000000000 -0500
+++ multipath-tools-0.4.8/libmultipath/checkers/rdac.c	2011-07-25 06:38:03.000000000 -0500
@@ -198,7 +198,10 @@ struct volume_access_inq
 	char PQ_PDT;
 	char dontcare0[7];
 	char avtcvp;
-	char dontcare1[39];
+	char dontcare1;
+	char asym_access_state_cur;
+	char vendor_specific_cur;
+	char dontcare2[36];
 };
 
 extern int
@@ -216,6 +219,14 @@ libcheck_check (struct checker * c)
 		ret = PATH_DOWN;
 		goto done;
 	}
+
+	/* check if controller is in service mode */
+	if ((inq.avtcvp & 0x10) &&
+	    ((inq.asym_access_state_cur & 0x0F) == 0x3) &&
+	    (inq.vendor_specific_cur == 0x7)) {
+		ret = PATH_DOWN;
+		goto done;
+	}
 
 	/* If owner set or ioship mode is enabled return PATH_UP always */
 	if ((inq.avtcvp & 0x1) || ((inq.avtcvp >> 5) & 0x1))