initramfs-live-boot: make it more generic and easy to use

The script was making some assumptions that enforced many requirement
in the machine kernel configuration and usage, besides it were too
while booting.

Changes included:

 * fix indentation;
 * rdepends on udev;
 * allow use of isofs as module;
 * remove rootdelay param parsing as it was unused;
 * don't verbosely kill udevd and mknod;
 * mount devtmpfs into rootfs, if available, before swithing root;

(From OE-Core rev: 3fc8cec53038f41d31344040c56d62aac90ba7e0)

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/initrdscripts/files/init-live.sh

@@ -13,6 +13,11 @@ early_setup() {
     mkdir /sys
     mount -t proc proc /proc
     mount -t sysfs sysfs /sys
+
+    # support modular kernel
+    modprobe isofs 2> /dev/null
+
+    mkdir /run
     udevd --daemon
     udevadm trigger --action=add
 }
@@ -25,21 +30,25 @@ read_args() {
             root=*)
                 ROOT_DEVICE=$optarg ;;
             rootfstype=*)
-                ROOT_FSTYPE=$optarg ;;
-            rootdelay=*)
-                rootdelay=$optarg ;;
-	    LABEL=*)
-		label=$optarg ;;
-	    video=*)
-		video_mode=$arg ;;
-	    vga=*)
-		vga_mode=$arg ;;
+                modprobe $optarg 2> /dev/null ;;
+            LABEL=*)
+                label=$optarg ;;
+            video=*)
+                video_mode=$arg ;;
+            vga=*)
+                vga_mode=$arg ;;
         esac
     done
 }
 
 boot_live_root() {
-    killall udevd
+    killall udevd 2>/dev/null
+
+    # use devtmpfs if available
+    if grep -q devtmpfs /proc/filesystems; then
+        mount -t devtmpfs devtmpfs $ROOT_MOUNT/dev
+    fi
+
     cd $ROOT_MOUNT
     exec switch_root -c /dev/console $ROOT_MOUNT /sbin/init
 }
@@ -78,7 +87,7 @@ done
 case $label in
     boot)
 	mkdir $ROOT_MOUNT
-	mknod /dev/loop0 b 7 0
+	mknod /dev/loop0 b 7 0 2>/dev/null
 
 	if ! $MOUNT -o rw,loop,noatime,nodiratime /media/$i/$ISOLINUX/$ROOT_IMAGE $ROOT_MOUNT ; then
 	    fatal "Couldnt mount rootfs image"
@@ -97,4 +106,3 @@ case $label in
 	fatal "Installation image failed"
 	;;
 esac
-

meta/recipes-core/initrdscripts/initramfs-live-boot_1.0.bb

@@ -1,9 +1,10 @@
 DESCRIPTION = "A live image init script"
 LICENSE = "MIT"
 LIC_FILES_CHKSUM = "file://${COREBASE}/meta/COPYING.MIT;md5=3da9cfbcb788c80a0384361b4de20420"
+RDEPENDS = "udev"
 SRC_URI = "file://init-live.sh"
 
-PR = "r6"
+PR = "r7"
 
 do_install() {
         install -m 0755 ${WORKDIR}/init-live.sh ${D}/init