Hello,
Attached herein is a patch for the dracut(8) tool. It adds support for the
lzop(1) & lz4(1) compression algorithms for creating initramfs images. Both
algorithms are supported by the Linux kernel.
Linux kernel also exports user's choice of initramfs compression algorithm to
a shell environment variable: INITRD_COMPRESS.
-> http://www.spinics.net/lists/mm-commits/msg100054.html
The attached patch recognises this variable, but sets it at lower precedence
than the command line options. Ie. dracut(8) command line options --gzip,
--bzip2 etc. would override the compression algorithm defined by the
$INITRD_COMPRESS environment variable.
Could someone please review this patch?
Thank you.
--
Prasad J Pandit / Red Hat Security Response Team
From 7e4cb9c5440c37b3d66c8144e884d005d96f49a5 Mon Sep 17 00:00:00 2001
From: P J P <ppandit@xxxxxxxxxx>
Date: Fri, 11 Oct 2013 19:26:51 +0530
Subject: Add lzo, lz4 compression and read INITRD_COMPRESS
This patch adds support for lzop(1) & lz4(1) compression
algorithms to compress iniramfs image file. Both are supported
by the Linux kernel.
Linux kernel exports user's choice of initramfs compression
algorithm as a shell environment variable: INITRD_COMPRESS.
This patch adds support to read this variable and duly compress
the initramfs image file.
Environment variable INITRD_COMPRESS has less precedence than the
command line options --gzip, etc. Ie. command line options could
override the compression algorithm defined by $INITRD_COMPRESS.
Signed-off-by: P J P <ppandit@xxxxxxxxxx>
diff --git a/dracut.sh b/dracut.sh
index d9533dd..173a259 100755
--- a/dracut.sh
+++ b/dracut.sh
@@ -165,6 +165,12 @@ Creates initial ramdisk images for preloading modules
--xz Compress the generated initramfs using xz.
Make sure that your kernel has xz support compiled
in, otherwise you will not be able to boot.
+ --lzo Compress the generated initramfs using lzop.
+ Make sure that your kernel has lzo support compiled
+ in, otherwise you will not be able to boot.
+ --lz4 Compress the generated initramfs using lz4.
+ Make sure that your kernel has lz4 support compiled
+ in, otherwise you will not be able to boot.
--compress [COMPRESSION] Compress the generated initramfs with the
passed compression program. Make sure your kernel
knows how to decompress the generated initramfs,
@@ -342,6 +348,8 @@ TEMP=$(unset POSIXLY_CORRECT; getopt \
--long bzip2 \
--long lzma \
--long xz \
+ --long lzo \
+ --long lz4 \
--long no-compress \
--long gzip \
--long list-modules \
@@ -430,6 +438,8 @@ while :; do
--bzip2) compress_l="bzip2";;
--lzma) compress_l="lzma";;
--xz) compress_l="xz";;
+ --lzo) compress_l="lzo";;
+ --lz4) compress_l="lz4";;
--no-compress) _no_compress_l="cat";;
--gzip) compress_l="gzip";;
--list-modules) do_list="yes";;
@@ -673,6 +683,7 @@ stdloglvl=$((stdloglvl + verbosity_mod_l))
[[ $fw_dir ]] || fw_dir="/lib/firmware/updates /lib/firmware"
[[ $tmpdir_l ]] && tmpdir="$tmpdir_l"
[[ $tmpdir ]] || tmpdir=/var/tmp
+[[ $INITRD_COMPRESS ]] && compress=$INITRD_COMPRESS
[[ $compress_l ]] && compress=$compress_l
[[ $show_modules_l ]] && show_modules=$show_modules_l
[[ $nofscks_l ]] && nofscks="yes"
@@ -689,6 +700,8 @@ case $compress in
lzma) compress="lzma -9";;
xz) compress="xz --check=crc32 --lzma2=dict=1MiB";;
gzip) compress="gzip -9"; command -v pigz > /dev/null 2>&1 && compress="pigz -9";;
+ lzo) compress="lzop -9";;
+ lz4) compress="lz4 -9";;
esac
if [[ $_no_compress_l = "cat" ]]; then
compress="cat"
--
1.8.3.1
