kbuild: rebuild initramfs if content of initramfs changes
initramfs.cpio.gz being build in usr/ and included in the
kernel was not rebuild when the included files changed.
To fix this the following was done:
- let gen_initramfs.sh generate a list of files and directories included
in the initramfs
- gen_initramfs generate the gzipped cpio archive so we could simplify
the kbuild file (Makefile)
- utilising the kbuild infrastructure so when uid/gid root mapping changes
the initramfs will be rebuild
With this change we have a much more robust initramfs generation.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/scripts/gen_initramfs_list.sh b/scripts/gen_initramfs_list.sh
index 6d41116..56b3bed 100644
--- a/scripts/gen_initramfs_list.sh
+++ b/scripts/gen_initramfs_list.sh
@@ -1,22 +1,55 @@
#!/bin/bash
# Copyright (C) Martin Schlemmer <azarah@nosferatu.za.org>
+# Copyright (c) 2006 Sam Ravnborg <sam@ravnborg.org>
+#
# Released under the terms of the GNU GPL
#
-# Generate a newline separated list of entries from the file/directory
-# supplied as an argument.
-#
-# If a file/directory is not supplied then generate a small dummy file.
-#
-# The output is suitable for gen_init_cpio built from usr/gen_init_cpio.c.
-#
+# Generate a cpio packed initramfs. It uses gen_init_cpio to generate
+# the cpio archive, and gzip to pack it.
+# The script may also be used to generate the inputfile used for gen_init_cpio
+# This script assumes that gen_init_cpio is located in usr/ directory
+
+# error out on errors
+set -e
+
+usage() {
+cat << EOF
+Usage:
+$0 [-o <file>] [-u <uid>] [-g <gid>] {-d | <cpio_source>} ...
+ -o <file> Create gzipped initramfs file named <file> using
+ gen_init_cpio and gzip
+ -u <uid> User ID to map to user ID 0 (root).
+ <uid> is only meaningful if <cpio_source>
+ is a directory.
+ -g <gid> Group ID to map to group ID 0 (root).
+ <gid> is only meaningful if <cpio_source>
+ is a directory.
+ <cpio_source> File list or directory for cpio archive.
+ If <cpio_source> is a .cpio file it will be used
+ as direct input to initramfs.
+ -d Output the default cpio list.
+
+All options except -o and -l may be repeated and are interpreted
+sequentially and immediately. -u and -g states are preserved across
+<cpio_source> options so an explicit "-u 0 -g 0" is required
+to reset the root/group mapping.
+EOF
+}
+
+list_default_initramfs() {
+ # echo usr/kinit/kinit
+ :
+}
default_initramfs() {
- cat <<-EOF
+ cat <<-EOF >> ${output}
# This is a very simple, default initramfs
dir /dev 0755 0 0
nod /dev/console 0600 0 0 c 5 1
dir /root 0700 0 0
+ # file /kinit usr/kinit/kinit 0755 0 0
+ # slink /init kinit 0755 0 0
EOF
}
@@ -42,18 +75,28 @@
return 0
}
-print_mtime() {
- local argv1="$1"
- local my_mtime="0"
-
- if [ -e "${argv1}" ]; then
- my_mtime=$(find "${argv1}" -printf "%T@\n" | sort -r | head -n 1)
- fi
-
- echo "# Last modified: ${my_mtime}"
- echo
+list_print_mtime() {
+ :
}
+print_mtime() {
+ local my_mtime="0"
+
+ if [ -e "$1" ]; then
+ my_mtime=$(find "$1" -printf "%T@\n" | sort -r | head -n 1)
+ fi
+
+ echo "# Last modified: ${my_mtime}" >> ${output}
+ echo "" >> ${output}
+}
+
+list_parse() {
+ echo "$1 \\"
+}
+
+# for each file print a line in following format
+# <filetype> <name> <path to file> <octal mode> <uid> <gid>
+# for links, devices etc the format differs. See gen_init_cpio for details
parse() {
local location="$1"
local name="${location/${srcdir}//}"
@@ -99,80 +142,112 @@
;;
esac
- echo "${str}"
+ echo "${str}" >> ${output}
return 0
}
-usage() {
- printf "Usage:\n"
- printf "$0 [ [-u <root_uid>] [-g <root_gid>] [-d | <cpio_source>] ] . . .\n"
- printf "\n"
- printf -- "-u <root_uid> User ID to map to user ID 0 (root).\n"
- printf " <root_uid> is only meaningful if <cpio_source>\n"
- printf " is a directory.\n"
- printf -- "-g <root_gid> Group ID to map to group ID 0 (root).\n"
- printf " <root_gid> is only meaningful if <cpio_source>\n"
- printf " is a directory.\n"
- printf "<cpio_source> File list or directory for cpio archive.\n"
- printf " If <cpio_source> is not provided then a\n"
- printf " a default list will be output.\n"
- printf -- "-d Output the default cpio list. If no <cpio_source>\n"
- printf " is given then the default cpio list will be output.\n"
- printf "\n"
- printf "All options may be repeated and are interpreted sequentially\n"
- printf "and immediately. -u and -g states are preserved across\n"
- printf "<cpio_source> options so an explicit \"-u 0 -g 0\" is required\n"
- printf "to reset the root/group mapping.\n"
+unknown_option() {
+ printf "ERROR: unknown option \"$arg\"\n" >&2
+ printf "If the filename validly begins with '-', " >&2
+ printf "then it must be prefixed\n" >&2
+ printf "by './' so that it won't be interpreted as an option." >&2
+ printf "\n" >&2
+ usage >&2
+ exit 1
}
-build_list() {
- printf "\n#####################\n# $cpio_source\n"
+list_header() {
+ echo "deps_initramfs := \\"
+}
- if [ -f "$cpio_source" ]; then
- print_mtime "$cpio_source"
- cat "$cpio_source"
- elif [ -d "$cpio_source" ]; then
- srcdir=$(echo "$cpio_source" | sed -e 's://*:/:g')
- dirlist=$(find "${srcdir}" -printf "%p %m %U %G\n" 2>/dev/null)
+header() {
+ printf "\n#####################\n# $1\n" >> ${output}
+}
- # If $dirlist is only one line, then the directory is empty
- if [ "$(echo "${dirlist}" | wc -l)" -gt 1 ]; then
- print_mtime "$cpio_source"
-
- echo "${dirlist}" | \
- while read x; do
- parse ${x}
- done
- else
- # Failsafe in case directory is empty
- default_initramfs
+# process one directory (incl sub-directories)
+dir_filelist() {
+ ${dep_list}header "$1"
+
+ srcdir=$(echo "$1" | sed -e 's://*:/:g')
+ dirlist=$(find "${srcdir}" -printf "%p %m %U %G\n" 2>/dev/null)
+
+ # If $dirlist is only one line, then the directory is empty
+ if [ "$(echo "${dirlist}" | wc -l)" -gt 1 ]; then
+ ${dep_list}print_mtime "$1"
+
+ echo "${dirlist}" | \
+ while read x; do
+ ${dep_list}parse ${x}
+ done
+ fi
+}
+
+# if only one file is specified and it is .cpio file then use it direct as fs
+# if a directory is specified then add all files in given direcotry to fs
+# if a regular file is specified assume it is in gen_initramfs format
+input_file() {
+ source="$1"
+ if [ -f "$1" ]; then
+ ${dep_list}header "$1"
+ is_cpio="$(echo "$1" | sed 's/^.*\.cpio/cpio/')"
+ if [ $2 -eq 0 -a ${is_cpio} == "cpio" ]; then
+ cpio_file=$1
+ [ ! -z ${dep_list} ] && echo "$1"
+ return 0
fi
+ if [ -z ${dep_list} ]; then
+ print_mtime "$1" >> ${output}
+ cat "$1" >> ${output}
+ else
+ grep ^file "$1" | cut -d ' ' -f 3
+ fi
+ elif [ -d "$1" ]; then
+ dir_filelist "$1"
else
- echo " $0: Cannot open '$cpio_source'" >&2
+ echo " ${prog}: Cannot open '$1'" >&2
exit 1
fi
}
-
+prog=$0
root_uid=0
root_gid=0
+dep_list=
+cpio_file=
+cpio_list=
+output="/dev/stdout"
+output_file=""
+arg="$1"
+case "$arg" in
+ "-l") # files included in initramfs - used by kbuild
+ dep_list="list_"
+ shift
+ ;;
+ "-o") # generate gzipped cpio image named $1
+ shift
+ output_file="$1"
+ cpio_list="$(mktemp ${TMPDIR:-/tmp}/cpiolist.XXXXXX)"
+ output=${cpio_list}
+ shift
+ ;;
+esac
while [ $# -gt 0 ]; do
arg="$1"
shift
case "$arg" in
- "-u")
+ "-u") # map $1 to uid=0 (root)
root_uid="$1"
shift
;;
- "-g")
+ "-g") # map $1 to gid=0 (root)
root_gid="$1"
shift
;;
- "-d")
+ "-d") # display default initramfs list
default_list="$arg"
- default_initramfs
+ ${dep_list}default_initramfs
;;
"-h")
usage
@@ -181,23 +256,27 @@
*)
case "$arg" in
"-"*)
- printf "ERROR: unknown option \"$arg\"\n" >&2
- printf "If the filename validly begins with '-', then it must be prefixed\n" >&2
- printf "by './' so that it won't be interpreted as an option." >&2
- printf "\n" >&2
- usage >&2
- exit 1
+ unknown_option
;;
- *)
- cpio_source="$arg"
- build_list
+ *) # input file/dir - process it
+ input_file "$arg" "$#"
;;
esac
;;
esac
done
-# spit out the default cpio list if a source hasn't been specified
-[ -z "$cpio_source" -a -z "$default_list" ] && default_initramfs
-
+# If output_file is set we will generate cpio archive and gzip it
+# we are carefull to delete tmp files
+if [ ! -z ${output_file} ]; then
+ if [ -z ${cpio_file} ]; then
+ cpio_tfile="$(mktemp ${TMPDIR:-/tmp}/cpiofile.XXXXXX)"
+ usr/gen_init_cpio ${cpio_list} > ${cpio_tfile}
+ else
+ cpio_tfile=${cpio_file}
+ fi
+ rm ${cpio_list}
+ cat ${cpio_tfile} | gzip -f -9 - > ${output_file}
+ [ -z ${cpio_file} ] && rm ${cpio_tfile}
+fi
exit 0