s390/cio: add ipldev keyword to cio_ignore

Provide an 'ipldev' keyword to cio_ignore to (un)ignore the
CCW or FCP based boot device.
Reviewed-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Documentation/s390/CommonIO

@@ -8,9 +8,9 @@ Command line parameters
 
   Enable logging of debug information in case of ccw device timeouts.
 
-* cio_ignore = {all} |
-	       {<device> | <range of devices>} |
-	       {!<device> | !<range of devices>}
+* cio_ignore = device[,device[,..]]
+
+	device := {all | [!]ipldev | [!]<devno> | [!]<devno>-<devno>}
 
   The given devices will be ignored by the common I/O-layer; no detection
   and device sensing will be done on any of those devices. The subchannel to 
@@ -24,9 +24,10 @@ Command line parameters
   device numbers (0xabcd or abcd, for 2.4 backward compatibility). If you
   give a device number 0xabcd, it will be interpreted as 0.0.abcd.
 
-  You can use the 'all' keyword to ignore all devices.
-  The '!' operator will cause the I/O-layer to _not_ ignore a device.
-  The command line is parsed from left to right.
+  You can use the 'all' keyword to ignore all devices. The 'ipldev' keyword can
+  be used to refer to the CCW based boot device (this is probably useful only
+  when combined with the '!' operator). The '!' operator will cause the I/O-layer
+  to _not_ ignore a device. The command line is parsed from left to right.
 
   For example, 
 	cio_ignore=0.0.0023-0.0.0042,0.0.4711

drivers/s390/cio/blacklist.c

 /*
  *   S/390 common I/O routines -- blacklisting of specific devices
  *
- *    Copyright IBM Corp. 1999, 2002
+ *    Copyright IBM Corp. 1999, 2013
  *    Author(s): Ingo Adlung (adlung@de.ibm.com)
  *		 Cornelia Huck (cornelia.huck@de.ibm.com)
  *		 Arnd Bergmann (arndb@de.ibm.com)
@@ -17,8 +17,9 @@
 #include <linux/ctype.h>
 #include <linux/device.h>
 
-#include <asm/cio.h>
 #include <asm/uaccess.h>
+#include <asm/cio.h>
+#include <asm/ipl.h>
 
 #include "blacklist.h"
 #include "cio.h"
@@ -172,6 +173,22 @@ static int blacklist_parse_parameters(char *str, range_action action,
 			to_cssid = __MAX_CSSID;
 			to_ssid = __MAX_SSID;
 			to = __MAX_SUBCHANNEL;
+		} else if (strcmp(parm, "ipldev") == 0) {
+			if (ipl_info.type == IPL_TYPE_CCW) {
+				from_cssid = 0;
+				from_ssid = ipl_info.data.ccw.dev_id.ssid;
+				from = ipl_info.data.ccw.dev_id.devno;
+			} else if (ipl_info.type == IPL_TYPE_FCP ||
+				   ipl_info.type == IPL_TYPE_FCP_DUMP) {
+				from_cssid = 0;
+				from_ssid = ipl_info.data.fcp.dev_id.ssid;
+				from = ipl_info.data.fcp.dev_id.devno;
+			} else {
+				continue;
+			}
+			to_cssid = from_cssid;
+			to_ssid = from_ssid;
+			to = from;
 		} else {
 			rc = parse_busid(strsep(&parm, "-"), &from_cssid,
 					 &from_ssid, &from, msgtrigger);