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/arch/i386/boot/compressed/misc.c

https://bitbucket.org/evzijst/gittest
C | 382 lines | 285 code | 65 blank | 32 comment | 39 complexity | d04a0957d80be2a8b0c4331781189b3c MD5 | raw file
  1/*
  2 * misc.c
  3 * 
  4 * This is a collection of several routines from gzip-1.0.3 
  5 * adapted for Linux.
  6 *
  7 * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
  8 * puts by Nick Holloway 1993, better puts by Martin Mares 1995
  9 * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
 10 */
 11
 12#include <linux/linkage.h>
 13#include <linux/vmalloc.h>
 14#include <linux/tty.h>
 15#include <video/edid.h>
 16#include <asm/io.h>
 17
 18/*
 19 * gzip declarations
 20 */
 21
 22#define OF(args)  args
 23#define STATIC static
 24
 25#undef memset
 26#undef memcpy
 27
 28/*
 29 * Why do we do this? Don't ask me..
 30 *
 31 * Incomprehensible are the ways of bootloaders.
 32 */
 33static void* memset(void *, int, size_t);
 34static void* memcpy(void *, __const void *, size_t);
 35#define memzero(s, n)     memset ((s), 0, (n))
 36
 37typedef unsigned char  uch;
 38typedef unsigned short ush;
 39typedef unsigned long  ulg;
 40
 41#define WSIZE 0x8000		/* Window size must be at least 32k, */
 42				/* and a power of two */
 43
 44static uch *inbuf;	     /* input buffer */
 45static uch window[WSIZE];    /* Sliding window buffer */
 46
 47static unsigned insize = 0;  /* valid bytes in inbuf */
 48static unsigned inptr = 0;   /* index of next byte to be processed in inbuf */
 49static unsigned outcnt = 0;  /* bytes in output buffer */
 50
 51/* gzip flag byte */
 52#define ASCII_FLAG   0x01 /* bit 0 set: file probably ASCII text */
 53#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
 54#define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
 55#define ORIG_NAME    0x08 /* bit 3 set: original file name present */
 56#define COMMENT      0x10 /* bit 4 set: file comment present */
 57#define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
 58#define RESERVED     0xC0 /* bit 6,7:   reserved */
 59
 60#define get_byte()  (inptr < insize ? inbuf[inptr++] : fill_inbuf())
 61		
 62/* Diagnostic functions */
 63#ifdef DEBUG
 64#  define Assert(cond,msg) {if(!(cond)) error(msg);}
 65#  define Trace(x) fprintf x
 66#  define Tracev(x) {if (verbose) fprintf x ;}
 67#  define Tracevv(x) {if (verbose>1) fprintf x ;}
 68#  define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
 69#  define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
 70#else
 71#  define Assert(cond,msg)
 72#  define Trace(x)
 73#  define Tracev(x)
 74#  define Tracevv(x)
 75#  define Tracec(c,x)
 76#  define Tracecv(c,x)
 77#endif
 78
 79static int  fill_inbuf(void);
 80static void flush_window(void);
 81static void error(char *m);
 82static void gzip_mark(void **);
 83static void gzip_release(void **);
 84  
 85/*
 86 * This is set up by the setup-routine at boot-time
 87 */
 88static unsigned char *real_mode; /* Pointer to real-mode data */
 89
 90#define RM_EXT_MEM_K   (*(unsigned short *)(real_mode + 0x2))
 91#ifndef STANDARD_MEMORY_BIOS_CALL
 92#define RM_ALT_MEM_K   (*(unsigned long *)(real_mode + 0x1e0))
 93#endif
 94#define RM_SCREEN_INFO (*(struct screen_info *)(real_mode+0))
 95
 96extern char input_data[];
 97extern int input_len;
 98
 99static long bytes_out = 0;
100static uch *output_data;
101static unsigned long output_ptr = 0;
102
103static void *malloc(int size);
104static void free(void *where);
105
106static void putstr(const char *);
107
108extern int end;
109static long free_mem_ptr = (long)&end;
110static long free_mem_end_ptr;
111
112#define INPLACE_MOVE_ROUTINE  0x1000
113#define LOW_BUFFER_START      0x2000
114#define LOW_BUFFER_MAX       0x90000
115#define HEAP_SIZE             0x3000
116static unsigned int low_buffer_end, low_buffer_size;
117static int high_loaded =0;
118static uch *high_buffer_start /* = (uch *)(((ulg)&end) + HEAP_SIZE)*/;
119
120static char *vidmem = (char *)0xb8000;
121static int vidport;
122static int lines, cols;
123
124#ifdef CONFIG_X86_NUMAQ
125static void * xquad_portio = NULL;
126#endif
127
128#include "../../../../lib/inflate.c"
129
130static void *malloc(int size)
131{
132	void *p;
133
134	if (size <0) error("Malloc error");
135	if (free_mem_ptr <= 0) error("Memory error");
136
137	free_mem_ptr = (free_mem_ptr + 3) & ~3;	/* Align */
138
139	p = (void *)free_mem_ptr;
140	free_mem_ptr += size;
141
142	if (free_mem_ptr >= free_mem_end_ptr)
143		error("Out of memory");
144
145	return p;
146}
147
148static void free(void *where)
149{	/* Don't care */
150}
151
152static void gzip_mark(void **ptr)
153{
154	*ptr = (void *) free_mem_ptr;
155}
156
157static void gzip_release(void **ptr)
158{
159	free_mem_ptr = (long) *ptr;
160}
161 
162static void scroll(void)
163{
164	int i;
165
166	memcpy ( vidmem, vidmem + cols * 2, ( lines - 1 ) * cols * 2 );
167	for ( i = ( lines - 1 ) * cols * 2; i < lines * cols * 2; i += 2 )
168		vidmem[i] = ' ';
169}
170
171static void putstr(const char *s)
172{
173	int x,y,pos;
174	char c;
175
176	x = RM_SCREEN_INFO.orig_x;
177	y = RM_SCREEN_INFO.orig_y;
178
179	while ( ( c = *s++ ) != '\0' ) {
180		if ( c == '\n' ) {
181			x = 0;
182			if ( ++y >= lines ) {
183				scroll();
184				y--;
185			}
186		} else {
187			vidmem [ ( x + cols * y ) * 2 ] = c; 
188			if ( ++x >= cols ) {
189				x = 0;
190				if ( ++y >= lines ) {
191					scroll();
192					y--;
193				}
194			}
195		}
196	}
197
198	RM_SCREEN_INFO.orig_x = x;
199	RM_SCREEN_INFO.orig_y = y;
200
201	pos = (x + cols * y) * 2;	/* Update cursor position */
202	outb_p(14, vidport);
203	outb_p(0xff & (pos >> 9), vidport+1);
204	outb_p(15, vidport);
205	outb_p(0xff & (pos >> 1), vidport+1);
206}
207
208static void* memset(void* s, int c, size_t n)
209{
210	int i;
211	char *ss = (char*)s;
212
213	for (i=0;i<n;i++) ss[i] = c;
214	return s;
215}
216
217static void* memcpy(void* __dest, __const void* __src,
218			    size_t __n)
219{
220	int i;
221	char *d = (char *)__dest, *s = (char *)__src;
222
223	for (i=0;i<__n;i++) d[i] = s[i];
224	return __dest;
225}
226
227/* ===========================================================================
228 * Fill the input buffer. This is called only when the buffer is empty
229 * and at least one byte is really needed.
230 */
231static int fill_inbuf(void)
232{
233	if (insize != 0) {
234		error("ran out of input data");
235	}
236
237	inbuf = input_data;
238	insize = input_len;
239	inptr = 1;
240	return inbuf[0];
241}
242
243/* ===========================================================================
244 * Write the output window window[0..outcnt-1] and update crc and bytes_out.
245 * (Used for the decompressed data only.)
246 */
247static void flush_window_low(void)
248{
249    ulg c = crc;         /* temporary variable */
250    unsigned n;
251    uch *in, *out, ch;
252    
253    in = window;
254    out = &output_data[output_ptr]; 
255    for (n = 0; n < outcnt; n++) {
256	    ch = *out++ = *in++;
257	    c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
258    }
259    crc = c;
260    bytes_out += (ulg)outcnt;
261    output_ptr += (ulg)outcnt;
262    outcnt = 0;
263}
264
265static void flush_window_high(void)
266{
267    ulg c = crc;         /* temporary variable */
268    unsigned n;
269    uch *in,  ch;
270    in = window;
271    for (n = 0; n < outcnt; n++) {
272	ch = *output_data++ = *in++;
273	if ((ulg)output_data == low_buffer_end) output_data=high_buffer_start;
274	c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
275    }
276    crc = c;
277    bytes_out += (ulg)outcnt;
278    outcnt = 0;
279}
280
281static void flush_window(void)
282{
283	if (high_loaded) flush_window_high();
284	else flush_window_low();
285}
286
287static void error(char *x)
288{
289	putstr("\n\n");
290	putstr(x);
291	putstr("\n\n -- System halted");
292
293	while(1);	/* Halt */
294}
295
296#define STACK_SIZE (4096)
297
298long user_stack [STACK_SIZE];
299
300struct {
301	long * a;
302	short b;
303	} stack_start = { & user_stack [STACK_SIZE] , __BOOT_DS };
304
305static void setup_normal_output_buffer(void)
306{
307#ifdef STANDARD_MEMORY_BIOS_CALL
308	if (RM_EXT_MEM_K < 1024) error("Less than 2MB of memory");
309#else
310	if ((RM_ALT_MEM_K > RM_EXT_MEM_K ? RM_ALT_MEM_K : RM_EXT_MEM_K) < 1024) error("Less than 2MB of memory");
311#endif
312	output_data = (char *)0x100000; /* Points to 1M */
313	free_mem_end_ptr = (long)real_mode;
314}
315
316struct moveparams {
317	uch *low_buffer_start;  int lcount;
318	uch *high_buffer_start; int hcount;
319};
320
321static void setup_output_buffer_if_we_run_high(struct moveparams *mv)
322{
323	high_buffer_start = (uch *)(((ulg)&end) + HEAP_SIZE);
324#ifdef STANDARD_MEMORY_BIOS_CALL
325	if (RM_EXT_MEM_K < (3*1024)) error("Less than 4MB of memory");
326#else
327	if ((RM_ALT_MEM_K > RM_EXT_MEM_K ? RM_ALT_MEM_K : RM_EXT_MEM_K) <
328			(3*1024))
329		error("Less than 4MB of memory");
330#endif	
331	mv->low_buffer_start = output_data = (char *)LOW_BUFFER_START;
332	low_buffer_end = ((unsigned int)real_mode > LOW_BUFFER_MAX
333	  ? LOW_BUFFER_MAX : (unsigned int)real_mode) & ~0xfff;
334	low_buffer_size = low_buffer_end - LOW_BUFFER_START;
335	high_loaded = 1;
336	free_mem_end_ptr = (long)high_buffer_start;
337	if ( (0x100000 + low_buffer_size) > ((ulg)high_buffer_start)) {
338		high_buffer_start = (uch *)(0x100000 + low_buffer_size);
339		mv->hcount = 0; /* say: we need not to move high_buffer */
340	}
341	else mv->hcount = -1;
342	mv->high_buffer_start = high_buffer_start;
343}
344
345static void close_output_buffer_if_we_run_high(struct moveparams *mv)
346{
347	if (bytes_out > low_buffer_size) {
348		mv->lcount = low_buffer_size;
349		if (mv->hcount)
350			mv->hcount = bytes_out - low_buffer_size;
351	} else {
352		mv->lcount = bytes_out;
353		mv->hcount = 0;
354	}
355}
356
357
358asmlinkage int decompress_kernel(struct moveparams *mv, void *rmode)
359{
360	real_mode = rmode;
361
362	if (RM_SCREEN_INFO.orig_video_mode == 7) {
363		vidmem = (char *) 0xb0000;
364		vidport = 0x3b4;
365	} else {
366		vidmem = (char *) 0xb8000;
367		vidport = 0x3d4;
368	}
369
370	lines = RM_SCREEN_INFO.orig_video_lines;
371	cols = RM_SCREEN_INFO.orig_video_cols;
372
373	if (free_mem_ptr < 0x100000) setup_normal_output_buffer();
374	else setup_output_buffer_if_we_run_high(mv);
375
376	makecrc();
377	putstr("Uncompressing Linux... ");
378	gunzip();
379	putstr("Ok, booting the kernel.\n");
380	if (high_loaded) close_output_buffer_if_we_run_high(mv);
381	return high_loaded;
382}