target/linux/generic/patches-2.6.31/053-lzo_compression_for_initramfs.patch

   1 --- a/lib/Kconfig
   2 +++ b/lib/Kconfig
   3 @@ -120,6 +120,10 @@ config DECOMPRESS_LZMA
   4  config DECOMPRESS_LZMA_NEEDED
   5          boolean
   6
   7 +config DECOMPRESS_LZO
   8 +       select LZO_DECOMPRESS
   9 +       tristate
  10 +
  11  #
  12  # Generic allocator support is selected if needed
  13  #
  14 --- a/lib/Makefile
  15 +++ b/lib/Makefile
  16 @@ -69,6 +69,7 @@ obj-$(CONFIG_LZO_DECOMPRESS) += lzo/
  17  lib-$(CONFIG_DECOMPRESS_GZIP) += decompress_inflate.o
  18  lib-$(CONFIG_DECOMPRESS_BZIP2) += decompress_bunzip2.o
  19  lib-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o
  20 +lib-$(CONFIG_DECOMPRESS_LZO) += decompress_unlzo.o
  21
  22  obj-$(CONFIG_TEXTSEARCH) += textsearch.o
  23  obj-$(CONFIG_TEXTSEARCH_KMP) += ts_kmp.o
  24 --- a/lib/decompress.c
  25 +++ b/lib/decompress.c
  26 @@ -9,6 +9,7 @@
  27  #include <linux/decompress/bunzip2.h>
  28  #include <linux/decompress/unlzma.h>
  29  #include <linux/decompress/inflate.h>
  30 +#include <linux/decompress/unlzo.h>
  31
  32  #include <linux/types.h>
  33  #include <linux/string.h>
  34 @@ -22,6 +23,9 @@
  35  #ifndef CONFIG_DECOMPRESS_LZMA
  36  # define unlzma NULL
  37  #endif
  38 +#ifndef CONFIG_DECOMPRESS_LZO
  39 +# define unlzo NULL
  40 +#endif
  41
  42  static const struct compress_format {
  43         unsigned char magic[2];
  44 @@ -32,6 +36,7 @@ static const struct compress_format {
  45         { {037, 0236}, "gzip", gunzip },
  46         { {0x42, 0x5a}, "bzip2", bunzip2 },
  47         { {0x5d, 0x00}, "lzma", unlzma },
  48 +       { {0x89, 0x4c}, "lzo", unlzo },
  49         { {0, 0}, NULL, NULL }
  50  };
  51
  52 --- a/usr/Kconfig
  53 +++ b/usr/Kconfig
  54 @@ -72,6 +72,15 @@ config RD_LZMA
  55           Support loading of a LZMA encoded initial ramdisk or cpio buffer
  56           If unsure, say N.
  57
  58 +config RD_LZO
  59 +       bool "Support initial ramdisks compressed using LZO" if EMBEDDED
  60 +       default !EMBEDDED
  61 +       depends on BLK_DEV_INITRD && HAVE_KERNEL_LZO
  62 +       select DECOMPRESS_LZO
  63 +       help
  64 +         Support loading of a LZO encoded initial ramdisk or cpio buffer
  65 +         If unsure, say N.
  66 +
  67  choice
  68         prompt "Built-in initramfs compression mode" if INITRAMFS_SOURCE!=""
  69         help
  70 @@ -108,16 +117,15 @@ config INITRAMFS_COMPRESSION_GZIP
  71         bool "Gzip"
  72         depends on RD_GZIP
  73         help
  74 -         The old and tried gzip compression. Its compression ratio is
  75 -         the poorest among the 3 choices; however its speed (both
  76 -         compression and decompression) is the fastest.
  77 +         The old and tried gzip compression. It provides a good balance
  78 +         between compression ratio and decompression speed.
  79
  80  config INITRAMFS_COMPRESSION_BZIP2
  81         bool "Bzip2"
  82         depends on RD_BZIP2
  83         help
  84           Its compression ratio and speed is intermediate.
  85 -         Decompression speed is slowest among the three.  The initramfs
  86 +         Decompression speed is slowest among the four.  The initramfs
  87           size is about 10% smaller with bzip2, in comparison to gzip.
  88           Bzip2 uses a large amount of memory. For modern kernels you
  89           will need at least 8MB RAM or more for booting.
  90 @@ -128,7 +136,15 @@ config INITRAMFS_COMPRESSION_LZMA
  91         help
  92           The most recent compression algorithm.
  93           Its ratio is best, decompression speed is between the other
  94 -         two. Compression is slowest.  The initramfs size is about 33%
  95 +         three. Compression is slowest. The initramfs size is about 33%
  96           smaller with LZMA in comparison to gzip.
  97
  98 +config INITRAMFS_COMPRESSION_LZO
  99 +       bool "LZO"
 100 +       depends on RD_LZO
 101 +       help
 102 +         Its compression ratio is the poorest among the four. The kernel
 103 +         size is about about 10% bigger than gzip; however its speed
 104 +         (both compression and decompression) is the fastest.
 105 +
 106  endchoice