Commit 2a2a400f authored by Albin Tonnerre's avatar Albin Tonnerre Committed by Linus Torvalds
Browse files

initramfs: add support for in-kernel initramfs compressed with LZO

Add the necessary parts to be enable the use of LZO-compressed initramfs
build into the kernel.
Signed-off-by: default avatarAlbin Tonnerre <>
Cc: "H. Peter Anvin" <>
Cc: Michal Marek <>
Signed-off-by: default avatarAndrew Morton <>
Signed-off-by: default avatarLinus Torvalds <>
parent edcd1d84
......@@ -242,6 +242,7 @@ case "$arg" in
echo "$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 "\.lzo$" && compr="lzop -9 -f"
echo "$output_file" | grep -q "\.cpio$" && compr="cat"
......@@ -15,6 +15,9 @@ suffix_$(CONFIG_INITRAMFS_COMPRESSION_BZIP2) = .bz2
# Lzma
# Lzo
# Generate builtin.o based on initramfs_data.o
obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data$(suffix_y).o
......@@ -45,7 +48,7 @@ endif
quiet_cmd_initfs = GEN $@
cmd_initfs = $(initramfs) -o $@ $(ramfs-args) $(ramfs-input)
targets := initramfs_data.cpio.gz initramfs_data.cpio.bz2 initramfs_data.cpio.lzma initramfs_data.cpio
targets := initramfs_data.cpio.gz initramfs_data.cpio.bz2 initramfs_data.cpio.lzma initramfs_data.cpio.lzo initramfs_data.cpio
# do not try to update files included in initramfs
$(deps_initramfs): ;
initramfs_data includes the compressed binary that is the
filesystem used for early user space.
Note: Older versions of "as" (prior to binutils
released on 2001-07-14) dit not support .incbin.
If you are forced to use older binutils than that then the
following trick can be applied to create the resulting binary:
ld -m elf_i386 --format binary --oformat elf32-i386 -r \
-T initramfs_data.scr initramfs_data.cpio.gz -o initramfs_data.o
ld -m elf_i386 -r -o built-in.o initramfs_data.o
initramfs_data.scr looks like this:
.init.ramfs : { *(.data) }
The above example is for i386 - the parameters vary from architectures.
Eventually look up LDFLAGS_BLOB in an older version of the
arch/$(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.lzo"
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment