[bzip2/lzma] fix for built-in initramfs issue

Alain Knaff
2009-01-06T21:57:50Z

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H. Peter Anvin wrote:
> Alain Knaff wrote:
>> H. Peter Anvin wrote:
>>> I'm thinking that with "preferred" we might just use the first one in
>>> the priority list "lzma, bzip2, gzip, uncompressed" depending on what is
>>> installed in the kernel.
>>>
>>> Using the kernel method may definitely not work, especially on
>>> architectures which don't do this style of kernel compression.
>>>
>>> -hpa
>>
>> Ok. For the new change, may I do a diff against the current
>> x86/lzma-setup , or should I do the whole 5-part dance again?
>>
>
> Go ahead and do an incremental patch at this point.
>
> -hpa

Here it is (see attachment)

Alain

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From: Alain Knaff <alain@knaff.lu>
Subject: [PATCH] init: fix built-in initramfs vs CONFIG_RD_GZIP

Impact: Consistency

Makes it possible to disable CONFIG_RD_GZIP . In that case, the
built-in initramfs will be compressed by whatever compressor is
available (bzip2 or lzma) or left uncompressed if none is available.

It also removes a couple of warnings which occur when no ramdisk
compression at all is chosen.

It also restores the select ZLIB_INFLATE in drivers/block/Kconfig
which somehow came missing. This is needed to activate compilation of
the stuff in zlib_deflate.

Signed-off-by: Alain Knaff <alain@knaff.lu>
---
diff -purN x86.ref/drivers/block/Kconfig x86-builtin-initramfs/drivers/block/Kconfig
--- x86.ref/drivers/block/Kconfig 2009-01-06 08:31:16.000000000 +0100
+++ x86-builtin-initramfs/drivers/block/Kconfig 2009-01-06 21:41:16.000000000 +0100
@@ -363,6 +363,7 @@ config RD_GZIP
default y
depends on BLK_DEV_INITRD=y
select DECOMPRESS_GZIP
+ select ZLIB_INFLATE
help
Support loading of a gzip encoded initial ramdisk or cpio buffer.
If unsure, say Y.
diff -purN x86.ref/init/initramfs.c x86-builtin-initramfs/init/initramfs.c
--- x86.ref/init/initramfs.c 2009-01-06 08:31:16.000000000 +0100
+++ x86-builtin-initramfs/init/initramfs.c 2009-01-06 22:27:26.000000000 +0100
@@ -389,7 +389,7 @@ static int __init write_buffer(char *buf
return len - count;
}

-
+#if defined CONFIG_RD_GZIP || defined CONFIG_RD_BZIP2 || defined CONFIG_RD_LZMA
static int __init flush_buffer(void *bufv, unsigned len)
{
char *buf = (char *) bufv;
@@ -412,6 +412,7 @@ static int __init flush_buffer(void *buf
}
return origLen;
}
+#endif

static unsigned my_inptr; /* index of next byte to be processed in inbuf */

@@ -449,10 +450,12 @@ static char * __init unpack_to_rootfs(ch
continue;
}
this_header = 0;
+#ifdef CONFIG_RD_GZIP
if (!gunzip(buf, len, NULL, flush_buffer, NULL,
&my_inptr, error) &&
message == NULL)
goto ok;
+#endif

#ifdef CONFIG_RD_BZIP2
message = NULL; /* Zero out message, or else cpio will
@@ -473,7 +476,9 @@ static char * __init unpack_to_rootfs(ch
goto ok;
}
#endif
+#if defined CONFIG_RD_GZIP || defined CONFIG_RD_BZIP2 || defined CONFIG_RD_LZMA
ok:
+#endif
if (state != Reset)
error("junk in compressed archive");
this_header = saved_offset + my_inptr;
diff -purN x86.ref/scripts/gen_initramfs_list.sh x86-builtin-initramfs/scripts/gen_initramfs_list.sh
--- x86.ref/scripts/gen_initramfs_list.sh 2009-01-05 01:21:06.000000000 +0100
+++ x86-builtin-initramfs/scripts/gen_initramfs_list.sh 2009-01-06 21:48:19.000000000 +0100
@@ -5,7 +5,7 @@
# Released under the terms of the GNU GPL
#
# Generate a cpio packed initramfs. It uses gen_init_cpio to generate
-# the cpio archive, and gzip to pack it.
+# the cpio archive, and then compresses 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

@@ -16,8 +16,8 @@ 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
+ -o <file> Create compressed initramfs file named <file> using
+ gen_init_cpio and compressor depending on the extension
-u <uid> User ID to map to user ID 0 (root).
<uid> is only meaningful if <cpio_source> is a
directory. "squash" forces all files to uid 0.
@@ -225,6 +225,7 @@ cpio_list=
output="/dev/stdout"
output_file=""
is_cpio_compressed=
+compr="gzip -9 -f"

arg="$1"
case "$arg" in
@@ -233,11 +234,15 @@ case "$arg" in
echo "deps_initramfs := \\"
shift
;;
- "-o") # generate gzipped cpio image named $1
+ "-o") # generate compressed cpio image named $1
shift
output_file="$1"
cpio_list="$(mktemp ${TMPDIR:-/tmp}/cpiolist.XXXXXX)"
output=${cpio_list}
+ echo "$output_file" | grep -q "\.gz$" && compr="gzip -9 -f"
+ echo "$output_file" | grep -q "\.bz2$" && compr="bzip2 -9 -f"
+ echo "$output_file" | grep -q "\.lzma$" && compr="lzma -9 -f"
+ echo "$output_file" | grep -q "\.cpio$" && compr="cat"
shift
;;
esac
@@ -274,7 +279,7 @@ while [ $# -gt 0 ]; do
esac
done

-# If output_file is set we will generate cpio archive and gzip it
+# If output_file is set we will generate cpio archive and compress it
# we are carefull to delete tmp files
if [ ! -z ${output_file} ]; then
if [ -z ${cpio_file} ]; then
@@ -287,7 +292,7 @@ if [ ! -z ${output_file} ]; then
if [ "${is_cpio_compressed}" = "compressed" ]; then
cat ${cpio_tfile} > ${output_file}
else
- cat ${cpio_tfile} | gzip -f -9 - > ${output_file}
+ cat ${cpio_tfile} | ${compr} - > ${output_file}
fi
[ -z ${cpio_file} ] && rm ${cpio_tfile}
fi
diff -purN x86.ref/usr/initramfs_data.bz2.S x86-builtin-initramfs/usr/initramfs_data.bz2.S
--- x86.ref/usr/initramfs_data.bz2.S 1970-01-01 01:00:00.000000000 +0100
+++ x86-builtin-initramfs/usr/initramfs_data.bz2.S 2009-01-06 20:54:00.000000000 +0100
@@ -0,0 +1,30 @@
+/*
+ initramfs_data includes the compressed binary that is the
+ filesystem used for early user space.
+ Note: Older versions of "as" (prior to binutils 2.11.90.0.23
+ released on 2001-07-14) dit not support .incbin.
+ If you are forced to use older binutils than that then the
+ following trick can be applied to create the resulting binary:
+
+
+ ld -m elf_i386 --format binary --oformat elf32-i386 -r \
+ -T initramfs_data.scr initramfs_data.cpio.gz -o initramfs_data.o
+ ld -m elf_i386 -r -o built-in.o initramfs_data.o
+
+ initramfs_data.scr looks like this:
+SECTIONS
+{
+ .init.ramfs : { *(.data) }
+}
+
+ The above example is for i386 - the parameters vary from architectures.
+ Eventually look up LDFLAGS_BLOB in an older version of the
+ arch/$(ARCH)/Makefile to see the flags used before .incbin was introduced.
+
+ Using .incbin has the advantage over ld that the correct flags are set
+ in the ELF header, as required by certain architectures.
+*/
+
+.section .init.ramfs,"a"
+.incbin "usr/initramfs_data.cpio.bz2"
+
diff -purN x86.ref/usr/initramfs_data.gz.S x86-builtin-initramfs/usr/initramfs_data.gz.S
--- x86.ref/usr/initramfs_data.gz.S 1970-01-01 01:00:00.000000000 +0100
+++ x86-builtin-initramfs/usr/initramfs_data.gz.S 2009-01-05 01:21:06.000000000 +0100
@@ -0,0 +1,30 @@
+/*
+ initramfs_data includes the compressed binary that is the
+ filesystem used for early user space.
+ Note: Older versions of "as" (prior to binutils 2.11.90.0.23
+ released on 2001-07-14) dit not support .incbin.
+ If you are forced to use older binutils than that then the
+ following trick can be applied to create the resulting binary:
+
+
+ ld -m elf_i386 --format binary --oformat elf32-i386 -r \
+ -T initramfs_data.scr initramfs_data.cpio.gz -o initramfs_data.o
+ ld -m elf_i386 -r -o built-in.o initramfs_data.o
+
+ initramfs_data.scr looks like this:
+SECTIONS
+{
+ .init.ramfs : { *(.data) }
+}
+
+ The above example is for i386 - the parameters vary from architectures.
+ Eventually look up LDFLAGS_BLOB in an older version of the
+ arch/$(ARCH)/Makefile to see the flags used before .incbin was introduced.
+
+ Using .incbin has the advantage over ld that the correct flags are set
+ in the ELF header, as required by certain architectures.
+*/
+
+.section .init.ramfs,"a"
+.incbin "usr/initramfs_data.cpio.gz"
+
diff -purN x86.ref/usr/initramfs_data.lzma.S x86-builtin-initramfs/usr/initramfs_data.lzma.S
--- x86.ref/usr/initramfs_data.lzma.S 1970-01-01 01:00:00.000000000 +0100
+++ x86-builtin-initramfs/usr/initramfs_data.lzma.S 2009-01-06 20:54:13.000000000 +0100
@@ -0,0 +1,30 @@
+/*
+ initramfs_data includes the compressed binary that is the
+ filesystem used for early user space.
+ Note: Older versions of "as" (prior to binutils 2.11.90.0.23
+ released on 2001-07-14) dit not support .incbin.
+ If you are forced to use older binutils than that then the
+ following trick can be applied to create the resulting binary:
+
+
+ ld -m elf_i386 --format binary --oformat elf32-i386 -r \
+ -T initramfs_data.scr initramfs_data.cpio.gz -o initramfs_data.o
+ ld -m elf_i386 -r -o built-in.o initramfs_data.o
+
+ initramfs_data.scr looks like this:
+SECTIONS
+{
+ .init.ramfs : { *(.data) }
+}
+
+ The above example is for i386 - the parameters vary from architectures.
+ Eventually look up LDFLAGS_BLOB in an older version of the
+ arch/$(ARCH)/Makefile to see the flags used before .incbin was introduced.
+
+ Using .incbin has the advantage over ld that the correct flags are set
+ in the ELF header, as required by certain architectures.
+*/
+
+.section .init.ramfs,"a"
+.incbin "usr/initramfs_data.cpio.lzma"
+
diff -purN x86.ref/usr/initramfs_data.S x86-builtin-initramfs/usr/initramfs_data.S
--- x86.ref/usr/initramfs_data.S 2009-01-05 01:21:06.000000000 +0100
+++ x86-builtin-initramfs/usr/initramfs_data.S 2009-01-06 20:54:18.000000000 +0100
@@ -26,5 +26,5 @@ SECTIONS
*/

.section .init.ramfs,"a"
-.incbin "usr/initramfs_data.cpio.gz"
+.incbin "usr/initramfs_data.cpio"

diff -purN x86.ref/usr/Makefile x86-builtin-initramfs/usr/Makefile
--- x86.ref/usr/Makefile 2009-01-05 01:21:06.000000000 +0100
+++ x86-builtin-initramfs/usr/Makefile 2009-01-06 22:23:48.000000000 +0100
@@ -5,14 +5,32 @@
klibcdirs:;
PHONY += klibcdirs

+# Find out "preferred" ramdisk compressor. Order of preference is
+# 1. bzip2 efficient, and likely to be present
+# 2. gzip former default
+# 3. lzma
+# 4. none
+
+# None of the above
+suffix_y =
+
+# Lzma, but no gzip nor bzip2
+suffix_$(CONFIG_RD_LZMA) = .lzma
+
+# Gzip, but no bzip2
+suffix_$(CONFIG_RD_GZIP) = .gz
+
+# Bzip2
+suffix_$(CONFIG_RD_BZIP2) = .bz2
+

# Generate builtin.o based on initramfs_data.o
-obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o
+obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data$(suffix_y).o

-# initramfs_data.o contains the initramfs_data.cpio.gz image.
+# initramfs_data.o contains the compressed initramfs_data.cpio image.
# The image is included using .incbin, a dependency which is not
# tracked automatically.
-$(obj)/initramfs_data.o: $(obj)/initramfs_data.cpio.gz FORCE
+$(obj)/initramfs_data$(suffix_y).o: $(obj)/initramfs_data.cpio$(suffix_y) FORCE

#####
# Generate the initramfs cpio archive
@@ -25,28 +43,28 @@ ramfs-args := \
$(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \
$(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID))

-# .initramfs_data.cpio.gz.d is used to identify all files included
+# .initramfs_data.cpio.d is used to identify all files included
# in initramfs and to detect if any files are added/removed.
# Removed files are identified by directory timestamp being updated
# The dependency list is generated by gen_initramfs.sh -l
-ifneq ($(wildcard $(obj)/.initramfs_data.cpio.gz.d),)
- include $(obj)/.initramfs_data.cpio.gz.d
+ifneq ($(wildcard $(obj)/.initramfs_data.cpio.d),)
+ include $(obj)/.initramfs_data.cpio.d
endif

quiet_cmd_initfs = GEN $@
cmd_initfs = $(initramfs) -o $@ $(ramfs-args) $(ramfs-input)

-targets := initramfs_data.cpio.gz
+targets := initramfs_data.cpio.gz initramfs_data.cpio.bz2 initramfs_data.cpio.lzma initramfs_data.cpio
# do not try to update files included in initramfs
$(deps_initramfs): ;

$(deps_initramfs): klibcdirs
-# We rebuild initramfs_data.cpio.gz if:
-# 1) Any included file is newer then initramfs_data.cpio.gz
+# We rebuild initramfs_data.cpio if:
+# 1) Any included file is newer then initramfs_data.cpio
# 2) There are changes in which files are included (added or deleted)
-# 3) If gen_init_cpio are newer than initramfs_data.cpio.gz
+# 3) If gen_init_cpio are newer than initramfs_data.cpio
# 4) arguments to gen_initramfs.sh changes
-$(obj)/initramfs_data.cpio.gz: $(obj)/gen_init_cpio $(deps_initramfs) klibcdirs
- $(Q)$(initramfs) -l $(ramfs-input) > $(obj)/.initramfs_data.cpio.gz.d
+$(obj)/initramfs_data.cpio$(suffix_y): $(obj)/gen_init_cpio $(deps_initramfs) klibcdirs
+ $(Q)$(initramfs) -l $(ramfs-input) > $(obj)/.initramfs_data.cpio.d
$(call if_changed,initfs)