Changeset 1099 in MondoRescue

Timestamp:

Feb 4, 2007, 7:35:31 AM (18 years ago)

Author:

andree

Message:

Add capability to mindi to detect what type of filesystem the kernel
will be able to access in initrd image during restore via new function
GetInitrdFilesystemToUse(). Currently detected are: ext2, cpio and
cramfs. Note that the latter is not currently implemented in terms of
creating the initrd image.

File:

• branches/stable/mindi/mindi (modified) (2 diffs)

branches/stable/mindi/mindi

@@ -826 +826 @@
 
 
+# Check kernel filesystem capabilites for accessing initrd image
+#
+# Interface definition:
+# param #1: absolute path to kernel image
+GetInitrdFilesystemToUse() {
+
+    # interface test: make sure we have one parameter
+    if [ $# -ne 1 ]; then
+        Die "GetInitrdFilesystemToUse(): Expected 1 parameter, got $#."
+    fi
+
+    # interface parameters
+    local lvKernelImage=$1
+
+    # local constants (filesystem magic strings)
+    local lcMagicCramfs="<3>cramfs: wrong magic"
+    local lcMagicExt2fs="<3>EXT2-fs: blocksize too small for device."
+    local lcMagicInitfs="<6>checking if image is initramfs..."
+
+    # local variables
+    local lvOffset
+    local lvScanRes
+    local lvUseFilesystem
+
+    # say where we are.
+    LogIt "  GetInitrdFilesystemToUse(): called with parameter: $lvKernelImage.\n"
+
+    # verify that file exists
+    [ ! -f $lvKernelImage ] && Die "File $lvKernelImage not found. Terminating."
+
+    # get offet of gzip magic "1f8b0800" in file
+    lvOffset=`od -vA n -t x1 $lvKernelImage | tr -d '[:space:]' | awk '{ print match($0, "1f8b0800")}'`
+    [ $lvOffset -eq 0 ] && Die "gzip magic not found in file $lvKernelImage. Terminating."
+    lvOffset=`expr $lvOffset / 2`
+    LogIt "  GetInitrdFilesystemToUse(): gzip magic found at lvOffset $lvOffset.\n"
+
+    # scan kernel image for initrd filessystem support
+    lvScanRes=`dd ibs=1 skip=$lvOffset if=$lvKernelImage obs=1M 2>/dev/null | gunzip -c | strings | grep -e "$lcMagicCramfs" -e "$lcMagicExt2fs" -e "$lcMagicInitfs"`
+
+    # determine which filesystem to use for initrd image: ext2fs, gzip'ed cpio (initramfs ) or cramfs
+    if [ `echo $lvScanRes | grep -c "$lcMagicExt2fs"` -eq 1 ]; then
+        lvUseFilesystem="ext2fs"
+    elif [ `echo $lvScanRes | grep -c "$lcMagicInitfs"` -eq 1 ]; then
+        lvUseFilesystem="initramfs"
+    elif [ `echo $lvScanRes | grep -c "$lcMagicCramfs"` -eq 1 ]; then
+        lvUseFilesystem="cramfs"
+    else
+        lvUseFilesystem="UNSUPPORTED"
+    fi
+
+    # say what we are using
+    LogIt "  GetInitrdFilesystemToUse(): Filesytem to use for initrd is $lvUseFilesystem.\n"
+
+    # return file system to use
+    echo "$lvUseFilesystem"
+
+}
+
 # Searches parent raid device of given disk device
 # $1: disk device (i.e. /dev/hda1)
@@ -2704 +2762 @@
     echo "$disksize" > $mountpoint/tmp/$disksize.siz
     find $mountpoint -name CVS -exec rm -rf '{}' \;
-    umount $mountpoint || Die "Cannot unmount $tempfile"
-    dd if=$tempfile bs=1k 2> /dev/null | gzip -v9 > $rdz_fname 2> /dev/null
+    # Determine what filesystem to use for initrd image
+    LogIt "Call GetInitrdFilesystemToUse() with parameter ${kernelpath} to get filesystem to use for initrd.\n"
+    gvFileSystem=`GetInitrdFilesystemToUse ${kernelpath}`
+    [ -z  gvFileSystem ] && Die "GetFilesystemToUse() failed. Terminating."
+    case "$gvFileSystem" in
+    "ext2fs")
+        # say what will be used
+            LogIt "Creating an ext2 initrd image..."
+        # kernel expects linuxrc in ext2 filesystem
+        ( cd $mountpoint && ln -s sbin/init linuxrc )
+        # unmount loop filesystem and create image file using the standard approach
+        umount $mountpoint || Die "Cannot unmount $tempfile"
+        dd if=$tempfile bs=1k 2> /dev/null | gzip -v9 > $rdz_fname 2> /dev/null
+        # log that we are done
+            LogIt "done.\n"
+    ;;
+    "initramfs")
+        # say what will be used
+            LogIt "Creating a gzip'ed cpio (AKA initramfs) initrd image..."
+        # make sure that cpio is there
+        which cpio &> /dev/null; [ $? -eq 0 ] || Die "cpio not found. Please install package cpio and try again."
+        # go into filesystem
+        cd $mountpoint
+        # kernel expects init in cpio filesystem
+        ln -s sbin/init init
+        # create cpio image file and unmount loop filesystem
+        find . -print | cpio -o -H newc | gzip -9 > $old_pwd/$rdz_fname 2> /dev/null
+        cd $old_pwd
+        umount $mountpoint || Die "Cannot unmount $tempfile"
+        # log that we are done
+            LogIt "done.\n"
+    ;;
+    *)
+        Die "Filesystem $gvFileSystem not supported for initrd image. Terminating."
+    ;;
+    esac
     if [ "$res" -eq "0" ] ; then
         echo -en "..."