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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * misc.c | |
818a08f8 IC |
3 | * |
4 | * This is a collection of several routines from gzip-1.0.3 | |
1da177e4 LT |
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 | ||
818a08f8 IC |
12 | /* |
13 | * we have to be careful, because no indirections are allowed here, and | |
14 | * paravirt_ops is a kind of one. As it will only run in baremetal anyway, | |
15 | * we just keep it from happening | |
16 | */ | |
d3561b7f | 17 | #undef CONFIG_PARAVIRT |
099e1377 | 18 | #ifdef CONFIG_X86_32 |
1965aae3 | 19 | #define _ASM_X86_DESC_H 1 |
099e1377 IC |
20 | #endif |
21 | ||
1da177e4 | 22 | #include <linux/linkage.h> |
7e7f358c | 23 | #include <linux/screen_info.h> |
099e1377 | 24 | #include <linux/elf.h> |
020878ac | 25 | #include <linux/io.h> |
968de4f0 | 26 | #include <asm/page.h> |
e69f202d | 27 | #include <asm/boot.h> |
23968f71 | 28 | #include <asm/bootparam.h> |
968de4f0 EB |
29 | |
30 | /* WARNING!! | |
31 | * This code is compiled with -fPIC and it is relocated dynamically | |
32 | * at run time, but no relocation processing is performed. | |
33 | * This means that it is not safe to place pointers in static structures. | |
34 | */ | |
35 | ||
36 | /* | |
37 | * Getting to provable safe in place decompression is hard. | |
27b46d76 | 38 | * Worst case behaviours need to be analyzed. |
968de4f0 EB |
39 | * Background information: |
40 | * | |
41 | * The file layout is: | |
42 | * magic[2] | |
43 | * method[1] | |
44 | * flags[1] | |
45 | * timestamp[4] | |
46 | * extraflags[1] | |
47 | * os[1] | |
48 | * compressed data blocks[N] | |
49 | * crc[4] orig_len[4] | |
50 | * | |
51 | * resulting in 18 bytes of non compressed data overhead. | |
52 | * | |
53 | * Files divided into blocks | |
54 | * 1 bit (last block flag) | |
55 | * 2 bits (block type) | |
56 | * | |
1180e01d IM |
57 | * 1 block occurs every 32K -1 bytes or when there 50% compression |
58 | * has been achieved. The smallest block type encoding is always used. | |
968de4f0 EB |
59 | * |
60 | * stored: | |
61 | * 32 bits length in bytes. | |
62 | * | |
63 | * fixed: | |
64 | * magic fixed tree. | |
65 | * symbols. | |
66 | * | |
67 | * dynamic: | |
68 | * dynamic tree encoding. | |
69 | * symbols. | |
70 | * | |
71 | * | |
72 | * The buffer for decompression in place is the length of the | |
73 | * uncompressed data, plus a small amount extra to keep the algorithm safe. | |
74 | * The compressed data is placed at the end of the buffer. The output | |
75 | * pointer is placed at the start of the buffer and the input pointer | |
76 | * is placed where the compressed data starts. Problems will occur | |
77 | * when the output pointer overruns the input pointer. | |
78 | * | |
79 | * The output pointer can only overrun the input pointer if the input | |
80 | * pointer is moving faster than the output pointer. A condition only | |
81 | * triggered by data whose compressed form is larger than the uncompressed | |
82 | * form. | |
83 | * | |
84 | * The worst case at the block level is a growth of the compressed data | |
85 | * of 5 bytes per 32767 bytes. | |
86 | * | |
87 | * The worst case internal to a compressed block is very hard to figure. | |
88 | * The worst case can at least be boundined by having one bit that represents | |
89 | * 32764 bytes and then all of the rest of the bytes representing the very | |
90 | * very last byte. | |
91 | * | |
92 | * All of which is enough to compute an amount of extra data that is required | |
93 | * to be safe. To avoid problems at the block level allocating 5 extra bytes | |
1180e01d IM |
94 | * per 32767 bytes of data is sufficient. To avoind problems internal to a |
95 | * block adding an extra 32767 bytes (the worst case uncompressed block size) | |
96 | * is sufficient, to ensure that in the worst case the decompressed data for | |
968de4f0 EB |
97 | * block will stop the byte before the compressed data for a block begins. |
98 | * To avoid problems with the compressed data's meta information an extra 18 | |
99 | * bytes are needed. Leading to the formula: | |
100 | * | |
101 | * extra_bytes = (uncompressed_size >> 12) + 32768 + 18 + decompressor_size. | |
102 | * | |
103 | * Adding 8 bytes per 32K is a bit excessive but much easier to calculate. | |
104 | * Adding 32768 instead of 32767 just makes for round numbers. | |
105 | * Adding the decompressor_size is necessary as it musht live after all | |
106 | * of the data as well. Last I measured the decompressor is about 14K. | |
27b46d76 | 107 | * 10K of actual data and 4K of bss. |
968de4f0 EB |
108 | * |
109 | */ | |
1da177e4 LT |
110 | |
111 | /* | |
112 | * gzip declarations | |
113 | */ | |
1180e01d | 114 | #define STATIC static |
1da177e4 LT |
115 | |
116 | #undef memset | |
117 | #undef memcpy | |
1180e01d | 118 | #define memzero(s, n) memset((s), 0, (n)) |
1da177e4 | 119 | |
1da177e4 | 120 | |
1da177e4 | 121 | static void error(char *m); |
fd77c7ca | 122 | |
1da177e4 LT |
123 | /* |
124 | * This is set up by the setup-routine at boot-time | |
125 | */ | |
23968f71 | 126 | static struct boot_params *real_mode; /* Pointer to real-mode data */ |
3b6b9293 | 127 | static int quiet; |
1da177e4 | 128 | |
6175ddf0 BG |
129 | void *memset(void *s, int c, size_t n); |
130 | void *memcpy(void *dest, const void *src, size_t n); | |
b79c4df7 | 131 | |
6bcb13b3 BC |
132 | static void __putstr(int, const char *); |
133 | #define putstr(__x) __putstr(0, __x) | |
1da177e4 | 134 | |
778cb929 IC |
135 | #ifdef CONFIG_X86_64 |
136 | #define memptr long | |
137 | #else | |
138 | #define memptr unsigned | |
139 | #endif | |
140 | ||
141 | static memptr free_mem_ptr; | |
142 | static memptr free_mem_end_ptr; | |
1da177e4 | 143 | |
03056c88 | 144 | static char *vidmem; |
1da177e4 LT |
145 | static int vidport; |
146 | static int lines, cols; | |
147 | ||
ae03c499 AK |
148 | #ifdef CONFIG_KERNEL_GZIP |
149 | #include "../../../../lib/decompress_inflate.c" | |
150 | #endif | |
151 | ||
152 | #ifdef CONFIG_KERNEL_BZIP2 | |
153 | #include "../../../../lib/decompress_bunzip2.c" | |
154 | #endif | |
155 | ||
156 | #ifdef CONFIG_KERNEL_LZMA | |
157 | #include "../../../../lib/decompress_unlzma.c" | |
158 | #endif | |
1da177e4 | 159 | |
13510997 AT |
160 | #ifdef CONFIG_KERNEL_LZO |
161 | #include "../../../../lib/decompress_unlzo.c" | |
162 | #endif | |
163 | ||
1da177e4 LT |
164 | static void scroll(void) |
165 | { | |
166 | int i; | |
167 | ||
fd77c7ca PC |
168 | memcpy(vidmem, vidmem + cols * 2, (lines - 1) * cols * 2); |
169 | for (i = (lines - 1) * cols * 2; i < lines * cols * 2; i += 2) | |
1da177e4 LT |
170 | vidmem[i] = ' '; |
171 | } | |
172 | ||
6bcb13b3 | 173 | static void __putstr(int error, const char *s) |
1da177e4 | 174 | { |
fd77c7ca | 175 | int x, y, pos; |
1da177e4 LT |
176 | char c; |
177 | ||
6bcb13b3 BC |
178 | #ifndef CONFIG_X86_VERBOSE_BOOTUP |
179 | if (!error) | |
180 | return; | |
181 | #endif | |
182 | ||
778cb929 | 183 | #ifdef CONFIG_X86_32 |
23968f71 KH |
184 | if (real_mode->screen_info.orig_video_mode == 0 && |
185 | lines == 0 && cols == 0) | |
a24e7851 | 186 | return; |
778cb929 | 187 | #endif |
a24e7851 | 188 | |
23968f71 KH |
189 | x = real_mode->screen_info.orig_x; |
190 | y = real_mode->screen_info.orig_y; | |
1da177e4 | 191 | |
fd77c7ca PC |
192 | while ((c = *s++) != '\0') { |
193 | if (c == '\n') { | |
1da177e4 | 194 | x = 0; |
fd77c7ca | 195 | if (++y >= lines) { |
1da177e4 LT |
196 | scroll(); |
197 | y--; | |
198 | } | |
199 | } else { | |
020878ac | 200 | vidmem[(x + cols * y) * 2] = c; |
fd77c7ca | 201 | if (++x >= cols) { |
1da177e4 | 202 | x = 0; |
fd77c7ca | 203 | if (++y >= lines) { |
1da177e4 LT |
204 | scroll(); |
205 | y--; | |
206 | } | |
207 | } | |
208 | } | |
209 | } | |
210 | ||
23968f71 KH |
211 | real_mode->screen_info.orig_x = x; |
212 | real_mode->screen_info.orig_y = y; | |
1da177e4 LT |
213 | |
214 | pos = (x + cols * y) * 2; /* Update cursor position */ | |
b02aae9c RH |
215 | outb(14, vidport); |
216 | outb(0xff & (pos >> 9), vidport+1); | |
217 | outb(15, vidport); | |
218 | outb(0xff & (pos >> 1), vidport+1); | |
1da177e4 LT |
219 | } |
220 | ||
6175ddf0 | 221 | void *memset(void *s, int c, size_t n) |
1da177e4 LT |
222 | { |
223 | int i; | |
ade1af77 | 224 | char *ss = s; |
1da177e4 | 225 | |
020878ac PC |
226 | for (i = 0; i < n; i++) |
227 | ss[i] = c; | |
1da177e4 LT |
228 | return s; |
229 | } | |
230 | ||
6175ddf0 | 231 | void *memcpy(void *dest, const void *src, size_t n) |
1da177e4 LT |
232 | { |
233 | int i; | |
ade1af77 JE |
234 | const char *s = src; |
235 | char *d = dest; | |
1da177e4 | 236 | |
020878ac PC |
237 | for (i = 0; i < n; i++) |
238 | d[i] = s[i]; | |
b79c4df7 | 239 | return dest; |
1da177e4 LT |
240 | } |
241 | ||
1da177e4 LT |
242 | |
243 | static void error(char *x) | |
244 | { | |
6bcb13b3 BC |
245 | __putstr(1, "\n\n"); |
246 | __putstr(1, x); | |
247 | __putstr(1, "\n\n -- System halted"); | |
1da177e4 | 248 | |
ff3cf856 IM |
249 | while (1) |
250 | asm("hlt"); | |
1da177e4 LT |
251 | } |
252 | ||
099e1377 IC |
253 | static void parse_elf(void *output) |
254 | { | |
255 | #ifdef CONFIG_X86_64 | |
256 | Elf64_Ehdr ehdr; | |
257 | Elf64_Phdr *phdrs, *phdr; | |
258 | #else | |
259 | Elf32_Ehdr ehdr; | |
260 | Elf32_Phdr *phdrs, *phdr; | |
261 | #endif | |
262 | void *dest; | |
263 | int i; | |
264 | ||
265 | memcpy(&ehdr, output, sizeof(ehdr)); | |
fd77c7ca | 266 | if (ehdr.e_ident[EI_MAG0] != ELFMAG0 || |
099e1377 IC |
267 | ehdr.e_ident[EI_MAG1] != ELFMAG1 || |
268 | ehdr.e_ident[EI_MAG2] != ELFMAG2 || | |
fd77c7ca | 269 | ehdr.e_ident[EI_MAG3] != ELFMAG3) { |
099e1377 IC |
270 | error("Kernel is not a valid ELF file"); |
271 | return; | |
272 | } | |
273 | ||
3b6b9293 KH |
274 | if (!quiet) |
275 | putstr("Parsing ELF... "); | |
099e1377 IC |
276 | |
277 | phdrs = malloc(sizeof(*phdrs) * ehdr.e_phnum); | |
278 | if (!phdrs) | |
279 | error("Failed to allocate space for phdrs"); | |
280 | ||
281 | memcpy(phdrs, output + ehdr.e_phoff, sizeof(*phdrs) * ehdr.e_phnum); | |
282 | ||
fd77c7ca | 283 | for (i = 0; i < ehdr.e_phnum; i++) { |
099e1377 IC |
284 | phdr = &phdrs[i]; |
285 | ||
286 | switch (phdr->p_type) { | |
287 | case PT_LOAD: | |
288 | #ifdef CONFIG_RELOCATABLE | |
289 | dest = output; | |
290 | dest += (phdr->p_paddr - LOAD_PHYSICAL_ADDR); | |
291 | #else | |
fd77c7ca | 292 | dest = (void *)(phdr->p_paddr); |
099e1377 IC |
293 | #endif |
294 | memcpy(dest, | |
295 | output + phdr->p_offset, | |
296 | phdr->p_filesz); | |
297 | break; | |
298 | default: /* Ignore other PT_* */ break; | |
299 | } | |
300 | } | |
301 | } | |
302 | ||
778cb929 | 303 | asmlinkage void decompress_kernel(void *rmode, memptr heap, |
1180e01d IM |
304 | unsigned char *input_data, |
305 | unsigned long input_len, | |
306 | unsigned char *output) | |
1da177e4 LT |
307 | { |
308 | real_mode = rmode; | |
309 | ||
3b6b9293 KH |
310 | if (real_mode->hdr.loadflags & QUIET_FLAG) |
311 | quiet = 1; | |
312 | ||
23968f71 | 313 | if (real_mode->screen_info.orig_video_mode == 7) { |
1da177e4 LT |
314 | vidmem = (char *) 0xb0000; |
315 | vidport = 0x3b4; | |
316 | } else { | |
317 | vidmem = (char *) 0xb8000; | |
318 | vidport = 0x3d4; | |
319 | } | |
320 | ||
23968f71 KH |
321 | lines = real_mode->screen_info.orig_video_lines; |
322 | cols = real_mode->screen_info.orig_video_cols; | |
1da177e4 | 323 | |
4c83d653 | 324 | free_mem_ptr = heap; /* Heap */ |
7c539764 | 325 | free_mem_end_ptr = heap + BOOT_HEAP_SIZE; |
968de4f0 | 326 | |
7ed42a28 PA |
327 | if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1)) |
328 | error("Destination address inappropriately aligned"); | |
778cb929 | 329 | #ifdef CONFIG_X86_64 |
7ed42a28 | 330 | if (heap > 0x3fffffffffffUL) |
778cb929 IC |
331 | error("Destination address too large"); |
332 | #else | |
4c83d653 | 333 | if (heap > ((-__PAGE_OFFSET-(512<<20)-1) & 0x7fffffff)) |
968de4f0 | 334 | error("Destination address too large"); |
7ed42a28 | 335 | #endif |
968de4f0 | 336 | #ifndef CONFIG_RELOCATABLE |
7ed42a28 | 337 | if ((unsigned long)output != LOAD_PHYSICAL_ADDR) |
968de4f0 EB |
338 | error("Wrong destination address"); |
339 | #endif | |
1da177e4 | 340 | |
3b6b9293 KH |
341 | if (!quiet) |
342 | putstr("\nDecompressing Linux... "); | |
ae03c499 | 343 | decompress(input_data, input_len, NULL, NULL, output, NULL, error); |
099e1377 | 344 | parse_elf(output); |
3b6b9293 KH |
345 | if (!quiet) |
346 | putstr("done.\nBooting the kernel.\n"); | |
968de4f0 | 347 | return; |
1da177e4 | 348 | } |