multipath additions

gen_cmdline.sh

@@ -83,6 +83,7 @@ longusage() {
   echo "	--lvm2			Include LVM support"
   echo "	--mdadm			Copy /etc/mdadm.conf to initramfs"
   echo "	--dmraid		Include DMRAID support"
+  echo "	--multipath		Include Multipath support"
   echo "	--slowusb		Enables extra pauses for slow USB CD boots"
   echo "	--bootloader=grub	Add new kernel to GRUB configuration"
   echo "	--linuxrc=<file>	Specifies a user created linuxrc"
@@ -275,6 +276,16 @@ parse_cmdline() {
 			CMD_DMRAID=1
 			print_info 2 "CMD_DMRAID: ${CMD_DMRAID}"
 			;;
+		--multipath)
+			if [ ! -e /usr/include/libdevmapper.h ]
+			then
+				echo 'Error: --multipath requires device-mapper to be installed'
+				echo '		 on the host;system; try "emerge device-mapper".'
+				exit 1
+			fi
+			CMD_MULTIPATH=1
+			print_info 2 "CMD_MULTIPATH: ${CMD_MULTIPATH}"
+			;;
 		--bootloader=*)
 			CMD_BOOTLOADER=`parse_opt "$*"`
 			print_info 2 "CMD_BOOTLOADER: ${CMD_BOOTLOADER}"