mirror of https://gitee.com/openkylin/linux.git
414 lines
10 KiB
C
414 lines
10 KiB
C
/*
|
|
* misc.c
|
|
*
|
|
* This is a collection of several routines from gzip-1.0.3
|
|
* adapted for Linux.
|
|
*
|
|
* malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
|
|
* puts by Nick Holloway 1993, better puts by Martin Mares 1995
|
|
* High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
|
|
*/
|
|
|
|
/*
|
|
* we have to be careful, because no indirections are allowed here, and
|
|
* paravirt_ops is a kind of one. As it will only run in baremetal anyway,
|
|
* we just keep it from happening
|
|
*/
|
|
#undef CONFIG_PARAVIRT
|
|
#ifdef CONFIG_X86_64
|
|
#define _LINUX_STRING_H_ 1
|
|
#define __LINUX_BITMAP_H 1
|
|
#endif
|
|
|
|
#include <linux/linkage.h>
|
|
#include <linux/screen_info.h>
|
|
#include <asm/io.h>
|
|
#include <asm/page.h>
|
|
#include <asm/boot.h>
|
|
|
|
/* WARNING!!
|
|
* This code is compiled with -fPIC and it is relocated dynamically
|
|
* at run time, but no relocation processing is performed.
|
|
* This means that it is not safe to place pointers in static structures.
|
|
*/
|
|
|
|
/*
|
|
* Getting to provable safe in place decompression is hard.
|
|
* Worst case behaviours need to be analyzed.
|
|
* Background information:
|
|
*
|
|
* The file layout is:
|
|
* magic[2]
|
|
* method[1]
|
|
* flags[1]
|
|
* timestamp[4]
|
|
* extraflags[1]
|
|
* os[1]
|
|
* compressed data blocks[N]
|
|
* crc[4] orig_len[4]
|
|
*
|
|
* resulting in 18 bytes of non compressed data overhead.
|
|
*
|
|
* Files divided into blocks
|
|
* 1 bit (last block flag)
|
|
* 2 bits (block type)
|
|
*
|
|
* 1 block occurs every 32K -1 bytes or when there 50% compression has been achieved.
|
|
* The smallest block type encoding is always used.
|
|
*
|
|
* stored:
|
|
* 32 bits length in bytes.
|
|
*
|
|
* fixed:
|
|
* magic fixed tree.
|
|
* symbols.
|
|
*
|
|
* dynamic:
|
|
* dynamic tree encoding.
|
|
* symbols.
|
|
*
|
|
*
|
|
* The buffer for decompression in place is the length of the
|
|
* uncompressed data, plus a small amount extra to keep the algorithm safe.
|
|
* The compressed data is placed at the end of the buffer. The output
|
|
* pointer is placed at the start of the buffer and the input pointer
|
|
* is placed where the compressed data starts. Problems will occur
|
|
* when the output pointer overruns the input pointer.
|
|
*
|
|
* The output pointer can only overrun the input pointer if the input
|
|
* pointer is moving faster than the output pointer. A condition only
|
|
* triggered by data whose compressed form is larger than the uncompressed
|
|
* form.
|
|
*
|
|
* The worst case at the block level is a growth of the compressed data
|
|
* of 5 bytes per 32767 bytes.
|
|
*
|
|
* The worst case internal to a compressed block is very hard to figure.
|
|
* The worst case can at least be boundined by having one bit that represents
|
|
* 32764 bytes and then all of the rest of the bytes representing the very
|
|
* very last byte.
|
|
*
|
|
* All of which is enough to compute an amount of extra data that is required
|
|
* to be safe. To avoid problems at the block level allocating 5 extra bytes
|
|
* per 32767 bytes of data is sufficient. To avoind problems internal to a block
|
|
* adding an extra 32767 bytes (the worst case uncompressed block size) is
|
|
* sufficient, to ensure that in the worst case the decompressed data for
|
|
* block will stop the byte before the compressed data for a block begins.
|
|
* To avoid problems with the compressed data's meta information an extra 18
|
|
* bytes are needed. Leading to the formula:
|
|
*
|
|
* extra_bytes = (uncompressed_size >> 12) + 32768 + 18 + decompressor_size.
|
|
*
|
|
* Adding 8 bytes per 32K is a bit excessive but much easier to calculate.
|
|
* Adding 32768 instead of 32767 just makes for round numbers.
|
|
* Adding the decompressor_size is necessary as it musht live after all
|
|
* of the data as well. Last I measured the decompressor is about 14K.
|
|
* 10K of actual data and 4K of bss.
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* 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;
|
|
|
|
#define WSIZE 0x80000000 /* 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 I report
|
|
* a 2G windows size, as that should
|
|
* always be larger than our output buffer.
|
|
*/
|
|
|
|
static uch *inbuf; /* input buffer */
|
|
static uch *window; /* Sliding window buffer, (and final output buffer) */
|
|
|
|
static unsigned insize; /* valid bytes in inbuf */
|
|
static unsigned inptr; /* index of next byte to be processed in inbuf */
|
|
static unsigned outcnt; /* bytes in output buffer */
|
|
|
|
/* gzip flag byte */
|
|
#define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
|
|
#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
|
|
#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
|
|
#define ORIG_NAME 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) {if(!(cond)) error(msg);}
|
|
# define Trace(x) fprintf x
|
|
# define Tracev(x) {if (verbose) fprintf x ;}
|
|
# define Tracevv(x) {if (verbose>1) fprintf x ;}
|
|
# define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
|
|
# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
|
|
#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);
|
|
static void gzip_mark(void **);
|
|
static void gzip_release(void **);
|
|
|
|
/*
|
|
* This is set up by the setup-routine at boot-time
|
|
*/
|
|
static unsigned char *real_mode; /* Pointer to real-mode data */
|
|
|
|
#define RM_EXT_MEM_K (*(unsigned short *)(real_mode + 0x2))
|
|
#ifndef STANDARD_MEMORY_BIOS_CALL
|
|
#define RM_ALT_MEM_K (*(unsigned long *)(real_mode + 0x1e0))
|
|
#endif
|
|
#define RM_SCREEN_INFO (*(struct screen_info *)(real_mode+0))
|
|
|
|
extern unsigned char input_data[];
|
|
extern int input_len;
|
|
|
|
static long bytes_out = 0;
|
|
|
|
static void *malloc(int size);
|
|
static void free(void *where);
|
|
|
|
static void *memset(void *s, int c, unsigned n);
|
|
static void *memcpy(void *dest, const void *src, unsigned n);
|
|
|
|
static void putstr(const char *);
|
|
|
|
#ifdef CONFIG_X86_64
|
|
#define memptr long
|
|
#else
|
|
#define memptr unsigned
|
|
#endif
|
|
|
|
static memptr free_mem_ptr;
|
|
static memptr free_mem_end_ptr;
|
|
|
|
#ifdef CONFIG_X86_64
|
|
#define HEAP_SIZE 0x7000
|
|
#else
|
|
#define HEAP_SIZE 0x4000
|
|
#endif
|
|
|
|
static char *vidmem = (char *)0xb8000;
|
|
static int vidport;
|
|
static int lines, cols;
|
|
|
|
#ifdef CONFIG_X86_NUMAQ
|
|
void *xquad_portio;
|
|
#endif
|
|
|
|
#include "../../../../lib/inflate.c"
|
|
|
|
static void *malloc(int size)
|
|
{
|
|
void *p;
|
|
|
|
if (size <0) error("Malloc error");
|
|
if (free_mem_ptr <= 0) error("Memory error");
|
|
|
|
free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
|
|
|
|
p = (void *)free_mem_ptr;
|
|
free_mem_ptr += size;
|
|
|
|
if (free_mem_ptr >= free_mem_end_ptr)
|
|
error("Out of memory");
|
|
|
|
return p;
|
|
}
|
|
|
|
static void free(void *where)
|
|
{ /* Don't care */
|
|
}
|
|
|
|
static void gzip_mark(void **ptr)
|
|
{
|
|
*ptr = (void *) free_mem_ptr;
|
|
}
|
|
|
|
static void gzip_release(void **ptr)
|
|
{
|
|
free_mem_ptr = (memptr) *ptr;
|
|
}
|
|
|
|
static void scroll(void)
|
|
{
|
|
int i;
|
|
|
|
memcpy ( vidmem, vidmem + cols * 2, ( lines - 1 ) * cols * 2 );
|
|
for ( i = ( lines - 1 ) * cols * 2; i < lines * cols * 2; i += 2 )
|
|
vidmem[i] = ' ';
|
|
}
|
|
|
|
static void putstr(const char *s)
|
|
{
|
|
int x,y,pos;
|
|
char c;
|
|
|
|
#ifdef CONFIG_X86_32
|
|
if (RM_SCREEN_INFO.orig_video_mode == 0 && lines == 0 && cols == 0)
|
|
return;
|
|
#endif
|
|
|
|
x = RM_SCREEN_INFO.orig_x;
|
|
y = RM_SCREEN_INFO.orig_y;
|
|
|
|
while ( ( c = *s++ ) != '\0' ) {
|
|
if ( c == '\n' ) {
|
|
x = 0;
|
|
if ( ++y >= lines ) {
|
|
scroll();
|
|
y--;
|
|
}
|
|
} else {
|
|
vidmem [(x + cols * y) * 2] = c;
|
|
if ( ++x >= cols ) {
|
|
x = 0;
|
|
if ( ++y >= lines ) {
|
|
scroll();
|
|
y--;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
RM_SCREEN_INFO.orig_x = x;
|
|
RM_SCREEN_INFO.orig_y = y;
|
|
|
|
pos = (x + cols * y) * 2; /* Update cursor position */
|
|
outb(14, vidport);
|
|
outb(0xff & (pos >> 9), vidport+1);
|
|
outb(15, vidport);
|
|
outb(0xff & (pos >> 1), vidport+1);
|
|
}
|
|
|
|
static void* memset(void* s, int c, unsigned n)
|
|
{
|
|
int i;
|
|
char *ss = s;
|
|
|
|
for (i=0;i<n;i++) ss[i] = c;
|
|
return s;
|
|
}
|
|
|
|
static void* memcpy(void* dest, const void* src, unsigned n)
|
|
{
|
|
int i;
|
|
const char *s = src;
|
|
char *d = dest;
|
|
|
|
for (i=0;i<n;i++) d[i] = s[i];
|
|
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.
|
|
*/
|
|
ulg c = crc; /* temporary variable */
|
|
unsigned n;
|
|
uch *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 += (ulg)outcnt;
|
|
outcnt = 0;
|
|
}
|
|
|
|
static void error(char *x)
|
|
{
|
|
putstr("\n\n");
|
|
putstr(x);
|
|
putstr("\n\n -- System halted");
|
|
|
|
while (1)
|
|
asm("hlt");
|
|
}
|
|
|
|
asmlinkage void decompress_kernel(void *rmode, memptr heap,
|
|
uch *input_data, unsigned long input_len,
|
|
uch *output)
|
|
{
|
|
real_mode = rmode;
|
|
|
|
if (RM_SCREEN_INFO.orig_video_mode == 7) {
|
|
vidmem = (char *) 0xb0000;
|
|
vidport = 0x3b4;
|
|
} else {
|
|
vidmem = (char *) 0xb8000;
|
|
vidport = 0x3d4;
|
|
}
|
|
|
|
lines = RM_SCREEN_INFO.orig_video_lines;
|
|
cols = RM_SCREEN_INFO.orig_video_cols;
|
|
|
|
window = output; /* Output buffer (Normally at 1M) */
|
|
free_mem_ptr = heap; /* Heap */
|
|
free_mem_end_ptr = heap + HEAP_SIZE;
|
|
inbuf = input_data; /* Input buffer */
|
|
insize = input_len;
|
|
inptr = 0;
|
|
|
|
#ifdef CONFIG_X86_64
|
|
if ((ulg)output & (__KERNEL_ALIGN - 1))
|
|
error("Destination address not 2M aligned");
|
|
if ((ulg)output >= 0xffffffffffUL)
|
|
error("Destination address too large");
|
|
#else
|
|
if ((u32)output & (CONFIG_PHYSICAL_ALIGN -1))
|
|
error("Destination address not CONFIG_PHYSICAL_ALIGN aligned");
|
|
if (heap > ((-__PAGE_OFFSET-(512<<20)-1) & 0x7fffffff))
|
|
error("Destination address too large");
|
|
#ifndef CONFIG_RELOCATABLE
|
|
if ((u32)output != LOAD_PHYSICAL_ADDR)
|
|
error("Wrong destination address");
|
|
#endif
|
|
#endif
|
|
|
|
makecrc();
|
|
putstr("\nDecompressing Linux... ");
|
|
gunzip();
|
|
putstr("done.\nBooting the kernel.\n");
|
|
return;
|
|
}
|