Add LZO compression support for initramfs and old-style initrd
Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Tested-by: Wu Zhangjin <wuzhangjin@gmail.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Russell King <rmk@arm.linux.org.uk>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/usr/Kconfig b/usr/Kconfig
index 1c3039f..e2721f5 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -72,6 +72,15 @@
Support loading of a LZMA encoded initial ramdisk or cpio buffer
If unsure, say N.
+config RD_LZO
+ bool "Support initial ramdisks compressed using LZO" if EMBEDDED
+ default !EMBEDDED
+ depends on BLK_DEV_INITRD
+ select DECOMPRESS_LZO
+ help
+ Support loading of a LZO encoded initial ramdisk or cpio buffer
+ If unsure, say N.
+
choice
prompt "Built-in initramfs compression mode" if INITRAMFS_SOURCE!=""
help
@@ -108,16 +117,15 @@
bool "Gzip"
depends on RD_GZIP
help
- The old and tried gzip compression. Its compression ratio is
- the poorest among the 3 choices; however its speed (both
- compression and decompression) is the fastest.
+ The old and tried gzip compression. It provides a good balance
+ between compression ratio and decompression speed.
config INITRAMFS_COMPRESSION_BZIP2
bool "Bzip2"
depends on RD_BZIP2
help
Its compression ratio and speed is intermediate.
- Decompression speed is slowest among the three. The initramfs
+ Decompression speed is slowest among the four. The initramfs
size is about 10% smaller with bzip2, in comparison to gzip.
Bzip2 uses a large amount of memory. For modern kernels you
will need at least 8MB RAM or more for booting.
@@ -128,7 +136,15 @@
help
The most recent compression algorithm.
Its ratio is best, decompression speed is between the other
- two. Compression is slowest. The initramfs size is about 33%
+ three. Compression is slowest. The initramfs size is about 33%
smaller with LZMA in comparison to gzip.
+config INITRAMFS_COMPRESSION_LZO
+ bool "LZO"
+ depends on RD_LZO
+ help
+ Its compression ratio is the poorest among the four. The kernel
+ size is about about 10% bigger than gzip; however its speed
+ (both compression and decompression) is the fastest.
+
endchoice