bzip2/lzma: x86 kernel compression support
Impact: Replaces x86 kernel decompressor with new code
This is the third part of the bzip2/lzma patch
The bzip patch is based on an idea by Christian Ludwig, includes support for
compressing the kernel with bzip2 or lzma rather than gzip. Both
compressors give smaller sizes than gzip. Lzma's decompresses faster
than bzip2.
It also supports ramdisks and initramfs' compressed using these two
compressors.
The functionality has been successfully used for a couple of years by
the udpcast project
This version applies to "tip" kernel 2.6.28
This part contains:
- support for new bzip2 and lzma kernel compression for x86
Signed-off-by: Alain Knaff <alain@knaff.lu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index da06221..e45be73 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -116,71 +116,13 @@
/*
* gzip declarations
*/
-
-#define OF(args) args
#define STATIC static
#undef memset
#undef memcpy
#define memzero(s, n) memset((s), 0, (n))
-typedef unsigned char uch;
-typedef unsigned short ush;
-typedef unsigned long ulg;
-/*
- * Window size must be at least 32k, and a power of two.
- * We don't actually have a window just a huge output buffer,
- * so we report a 2G window size, as that should always be
- * larger than our output buffer:
- */
-#define WSIZE 0x80000000
-
-/* Input buffer: */
-static unsigned char *inbuf;
-
-/* Sliding window buffer (and final output buffer): */
-static unsigned char *window;
-
-/* Valid bytes in inbuf: */
-static unsigned insize;
-
-/* Index of next byte to be processed in inbuf: */
-static unsigned inptr;
-
-/* Bytes in output buffer: */
-static unsigned outcnt;
-
-/* gzip flag byte */
-#define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
-#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gz file */
-#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
-#define ORIG_NAM 0x08 /* bit 3 set: original file name present */
-#define COMMENT 0x10 /* bit 4 set: file comment present */
-#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
-#define RESERVED 0xC0 /* bit 6, 7: reserved */
-
-#define get_byte() (inptr < insize ? inbuf[inptr++] : fill_inbuf())
-
-/* Diagnostic functions */
-#ifdef DEBUG
-# define Assert(cond, msg) do { if (!(cond)) error(msg); } while (0)
-# define Trace(x) do { fprintf x; } while (0)
-# define Tracev(x) do { if (verbose) fprintf x ; } while (0)
-# define Tracevv(x) do { if (verbose > 1) fprintf x ; } while (0)
-# define Tracec(c, x) do { if (verbose && (c)) fprintf x ; } while (0)
-# define Tracecv(c, x) do { if (verbose > 1 && (c)) fprintf x ; } while (0)
-#else
-# define Assert(cond, msg)
-# define Trace(x)
-# define Tracev(x)
-# define Tracevv(x)
-# define Tracec(c, x)
-# define Tracecv(c, x)
-#endif
-
-static int fill_inbuf(void);
-static void flush_window(void);
static void error(char *m);
/*
@@ -189,13 +131,8 @@
static struct boot_params *real_mode; /* Pointer to real-mode data */
static int quiet;
-extern unsigned char input_data[];
-extern int input_len;
-
-static long bytes_out;
-
static void *memset(void *s, int c, unsigned n);
-static void *memcpy(void *dest, const void *src, unsigned n);
+void *memcpy(void *dest, const void *src, unsigned n);
static void __putstr(int, const char *);
#define putstr(__x) __putstr(0, __x)
@@ -213,7 +150,17 @@
static int vidport;
static int lines, cols;
-#include "../../../../lib/inflate.c"
+#ifdef CONFIG_KERNEL_GZIP
+#include "../../../../lib/decompress_inflate.c"
+#endif
+
+#ifdef CONFIG_KERNEL_BZIP2
+#include "../../../../lib/decompress_bunzip2.c"
+#endif
+
+#ifdef CONFIG_KERNEL_LZMA
+#include "../../../../lib/decompress_unlzma.c"
+#endif
static void scroll(void)
{
@@ -282,7 +229,7 @@
return s;
}
-static void *memcpy(void *dest, const void *src, unsigned n)
+void *memcpy(void *dest, const void *src, unsigned n)
{
int i;
const char *s = src;
@@ -293,38 +240,6 @@
return dest;
}
-/* ===========================================================================
- * Fill the input buffer. This is called only when the buffer is empty
- * and at least one byte is really needed.
- */
-static int fill_inbuf(void)
-{
- error("ran out of input data");
- return 0;
-}
-
-/* ===========================================================================
- * Write the output window window[0..outcnt-1] and update crc and bytes_out.
- * (Used for the decompressed data only.)
- */
-static void flush_window(void)
-{
- /* With my window equal to my output buffer
- * I only need to compute the crc here.
- */
- unsigned long c = crc; /* temporary variable */
- unsigned n;
- unsigned char *in, ch;
-
- in = window;
- for (n = 0; n < outcnt; n++) {
- ch = *in++;
- c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
- }
- crc = c;
- bytes_out += (unsigned long)outcnt;
- outcnt = 0;
-}
static void error(char *x)
{
@@ -407,12 +322,8 @@
lines = real_mode->screen_info.orig_video_lines;
cols = real_mode->screen_info.orig_video_cols;
- window = output; /* Output buffer (Normally at 1M) */
free_mem_ptr = heap; /* Heap */
free_mem_end_ptr = heap + BOOT_HEAP_SIZE;
- inbuf = input_data; /* Input buffer */
- insize = input_len;
- inptr = 0;
#ifdef CONFIG_X86_64
if ((unsigned long)output & (__KERNEL_ALIGN - 1))
@@ -430,10 +341,9 @@
#endif
#endif
- makecrc();
if (!quiet)
putstr("\nDecompressing Linux... ");
- gunzip();
+ decompress(input_data, input_len, NULL, NULL, output, NULL, error);
parse_elf(output);
if (!quiet)
putstr("done.\nBooting the kernel.\n");