From: Lasse Collin Date: Thu, 2 Dec 2010 19:14:57 +0000 (+0200) Subject: x86: Support XZ-compressed kernel X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Fpkl%2Fsquashfs-xz.git;a=commitdiff_plain;h=d4ad78414e5312126127b1f88cdaf8584af3eef1 x86: Support XZ-compressed kernel This integrates the XZ decompression code to the x86 pre-boot code. mkpiggy.c is updated to reserve about 32 KiB more buffer safety margin for kernel decompression. It is done unconditionally for all decompressors to keep the code simpler. The XZ decompressor needs around 30 KiB of heap, so the heap size is increased to 32 KiB on both x86-32 and x86-64. Documentation/x86/boot.txt is updated to list the XZ magic number. With the x86 BCJ filter in XZ, XZ-compressed x86 kernel tends to be a few percent smaller than the equivalent LZMA-compressed kernel. Signed-off-by: Lasse Collin --- diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt index 30b43e1..3988cde 100644 --- a/Documentation/x86/boot.txt +++ b/Documentation/x86/boot.txt @@ -621,9 +621,9 @@ Protocol: 2.08+ The payload may be compressed. The format of both the compressed and uncompressed data should be determined using the standard magic numbers. The currently supported compression formats are gzip - (magic numbers 1F 8B or 1F 9E), bzip2 (magic number 42 5A) and LZMA - (magic number 5D 00). The uncompressed payload is currently always ELF - (magic number 7F 45 4C 46). + (magic numbers 1F 8B or 1F 9E), bzip2 (magic number 42 5A), LZMA + (magic number 5D 00), and XZ (magic number FD 37). The uncompressed + payload is currently always ELF (magic number 7F 45 4C 46). Field name: payload_length Type: read diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index cea0cd9..f3db0d7 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -51,6 +51,7 @@ config X86 select HAVE_KERNEL_GZIP select HAVE_KERNEL_BZIP2 select HAVE_KERNEL_LZMA + select HAVE_KERNEL_XZ select HAVE_KERNEL_LZO select HAVE_HW_BREAKPOINT select HAVE_MIXED_BREAKPOINTS_REGS diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 0c22955..09664ef 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -4,7 +4,7 @@ # create a compressed vmlinux image from the original vmlinux # -targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma vmlinux.bin.lzo head_$(BITS).o misc.o string.o cmdline.o early_serial_console.o piggy.o +targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma vmlinux.bin.xz vmlinux.bin.lzo head_$(BITS).o misc.o string.o cmdline.o early_serial_console.o piggy.o KBUILD_CFLAGS := -m$(BITS) -D__KERNEL__ $(LINUX_INCLUDE) -O2 KBUILD_CFLAGS += -fno-strict-aliasing -fPIC @@ -49,12 +49,15 @@ $(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y) FORCE $(call if_changed,bzip2) $(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y) FORCE $(call if_changed,lzma) +$(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y) FORCE + $(call if_changed,xzkern) $(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y) FORCE $(call if_changed,lzo) suffix-$(CONFIG_KERNEL_GZIP) := gz suffix-$(CONFIG_KERNEL_BZIP2) := bz2 suffix-$(CONFIG_KERNEL_LZMA) := lzma +suffix-$(CONFIG_KERNEL_XZ) := xz suffix-$(CONFIG_KERNEL_LZO) := lzo quiet_cmd_mkpiggy = MKPIGGY $@ diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index 8f7bef8..6d4cab7 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -139,6 +139,10 @@ static int lines, cols; #include "../../../../lib/decompress_unlzma.c" #endif +#ifdef CONFIG_KERNEL_XZ +#include "../../../../lib/decompress_unxz.c" +#endif + #ifdef CONFIG_KERNEL_LZO #include "../../../../lib/decompress_unlzo.c" #endif diff --git a/arch/x86/boot/compressed/mkpiggy.c b/arch/x86/boot/compressed/mkpiggy.c index 5c22812..646aa78 100644 --- a/arch/x86/boot/compressed/mkpiggy.c +++ b/arch/x86/boot/compressed/mkpiggy.c @@ -74,7 +74,7 @@ int main(int argc, char *argv[]) offs = (olen > ilen) ? olen - ilen : 0; offs += olen >> 12; /* Add 8 bytes for each 32K block */ - offs += 32*1024 + 18; /* Add 32K + 18 bytes slack */ + offs += 64*1024 + 128; /* Add 64K + 128 bytes slack */ offs = (offs+4095) & ~4095; /* Round to a 4K boundary */ printf(".section \".rodata..compressed\",\"a\",@progbits\n"); diff --git a/arch/x86/include/asm/boot.h b/arch/x86/include/asm/boot.h index 3b62ab5..5e1a2ee 100644 --- a/arch/x86/include/asm/boot.h +++ b/arch/x86/include/asm/boot.h @@ -32,11 +32,7 @@ #define BOOT_HEAP_SIZE 0x400000 #else /* !CONFIG_KERNEL_BZIP2 */ -#ifdef CONFIG_X86_64 -#define BOOT_HEAP_SIZE 0x7000 -#else -#define BOOT_HEAP_SIZE 0x4000 -#endif +#define BOOT_HEAP_SIZE 0x8000 #endif /* !CONFIG_KERNEL_BZIP2 */