From 2a2a400f66e9e23eba960905c36dd37904bd9970 Mon Sep 17 00:00:00 2001 From: Albin Tonnerre Date: Wed, 26 May 2010 14:44:28 -0700 Subject: 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: Albin Tonnerre Cc: "H. Peter Anvin" Cc: Michal Marek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- usr/Makefile | 5 ++++- usr/initramfs_data.lzo.S | 29 +++++++++++++++++++++++++++++ 2 files changed, 33 insertions(+), 1 deletion(-) create mode 100644 usr/initramfs_data.lzo.S (limited to 'usr') diff --git a/usr/Makefile b/usr/Makefile index 1e6a9e4a72cc..6b4b6da0b67d 100644 --- a/usr/Makefile +++ b/usr/Makefile @@ -15,6 +15,9 @@ suffix_$(CONFIG_INITRAMFS_COMPRESSION_BZIP2) = .bz2 # Lzma suffix_$(CONFIG_INITRAMFS_COMPRESSION_LZMA) = .lzma +# Lzo +suffix_$(CONFIG_INITRAMFS_COMPRESSION_LZO) = .lzo + # Generate builtin.o based on initramfs_data.o obj-$(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 $(deps_initramfs): ; diff --git a/usr/initramfs_data.lzo.S b/usr/initramfs_data.lzo.S new file mode 100644 index 000000000000..59211905da84 --- /dev/null +++ b/usr/initramfs_data.lzo.S @@ -0,0 +1,29 @@ +/* + initramfs_data includes the compressed binary that is the + filesystem used for early user space. + Note: Older versions of "as" (prior to binutils 2.11.90.0.23 + released on 2001-07-14) dit not support .incbin. + If you are forced to use older binutils than that then the + following trick can be applied to create the resulting binary: + + + ld -m elf_i386 --format binary --oformat elf32-i386 -r \ + -T initramfs_data.scr initramfs_data.cpio.gz -o initramfs_data.o + ld -m elf_i386 -r -o built-in.o initramfs_data.o + + initramfs_data.scr looks like this: +SECTIONS +{ + .init.ramfs : { *(.data) } +} + + The above example is for i386 - the parameters vary from architectures. + Eventually look up LDFLAGS_BLOB in an older version of the + arch/$(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.lzo" -- cgit v1.2.3