Contents of /alx-src/tags/kernel26-2.6.12-alx-r9/init/initramfs.c
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Wed Mar 4 11:03:09 2009 UTC (15 years, 3 months ago) by niro
File MIME type: text/plain
File size: 10186 byte(s)
Wed Mar 4 11:03:09 2009 UTC (15 years, 3 months ago) by niro
File MIME type: text/plain
File size: 10186 byte(s)
Tag kernel26-2.6.12-alx-r9
1 | #include <linux/init.h> |
2 | #include <linux/fs.h> |
3 | #include <linux/slab.h> |
4 | #include <linux/types.h> |
5 | #include <linux/fcntl.h> |
6 | #include <linux/delay.h> |
7 | #include <linux/string.h> |
8 | #include <linux/syscalls.h> |
9 | |
10 | static __initdata char *message; |
11 | static void __init error(char *x) |
12 | { |
13 | if (!message) |
14 | message = x; |
15 | } |
16 | |
17 | static void __init *malloc(size_t size) |
18 | { |
19 | return kmalloc(size, GFP_KERNEL); |
20 | } |
21 | |
22 | static void __init free(void *where) |
23 | { |
24 | kfree(where); |
25 | } |
26 | |
27 | /* link hash */ |
28 | |
29 | static __initdata struct hash { |
30 | int ino, minor, major; |
31 | struct hash *next; |
32 | char *name; |
33 | } *head[32]; |
34 | |
35 | static inline int hash(int major, int minor, int ino) |
36 | { |
37 | unsigned long tmp = ino + minor + (major << 3); |
38 | tmp += tmp >> 5; |
39 | return tmp & 31; |
40 | } |
41 | |
42 | static char __init *find_link(int major, int minor, int ino, char *name) |
43 | { |
44 | struct hash **p, *q; |
45 | for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) { |
46 | if ((*p)->ino != ino) |
47 | continue; |
48 | if ((*p)->minor != minor) |
49 | continue; |
50 | if ((*p)->major != major) |
51 | continue; |
52 | return (*p)->name; |
53 | } |
54 | q = (struct hash *)malloc(sizeof(struct hash)); |
55 | if (!q) |
56 | panic("can't allocate link hash entry"); |
57 | q->ino = ino; |
58 | q->minor = minor; |
59 | q->major = major; |
60 | q->name = name; |
61 | q->next = NULL; |
62 | *p = q; |
63 | return NULL; |
64 | } |
65 | |
66 | static void __init free_hash(void) |
67 | { |
68 | struct hash **p, *q; |
69 | for (p = head; p < head + 32; p++) { |
70 | while (*p) { |
71 | q = *p; |
72 | *p = q->next; |
73 | free(q); |
74 | } |
75 | } |
76 | } |
77 | |
78 | /* cpio header parsing */ |
79 | |
80 | static __initdata unsigned long ino, major, minor, nlink; |
81 | static __initdata mode_t mode; |
82 | static __initdata unsigned long body_len, name_len; |
83 | static __initdata uid_t uid; |
84 | static __initdata gid_t gid; |
85 | static __initdata unsigned rdev; |
86 | |
87 | static void __init parse_header(char *s) |
88 | { |
89 | unsigned long parsed[12]; |
90 | char buf[9]; |
91 | int i; |
92 | |
93 | buf[8] = '\0'; |
94 | for (i = 0, s += 6; i < 12; i++, s += 8) { |
95 | memcpy(buf, s, 8); |
96 | parsed[i] = simple_strtoul(buf, NULL, 16); |
97 | } |
98 | ino = parsed[0]; |
99 | mode = parsed[1]; |
100 | uid = parsed[2]; |
101 | gid = parsed[3]; |
102 | nlink = parsed[4]; |
103 | body_len = parsed[6]; |
104 | major = parsed[7]; |
105 | minor = parsed[8]; |
106 | rdev = new_encode_dev(MKDEV(parsed[9], parsed[10])); |
107 | name_len = parsed[11]; |
108 | } |
109 | |
110 | /* FSM */ |
111 | |
112 | static __initdata enum state { |
113 | Start, |
114 | Collect, |
115 | GotHeader, |
116 | SkipIt, |
117 | GotName, |
118 | CopyFile, |
119 | GotSymlink, |
120 | Reset |
121 | } state, next_state; |
122 | |
123 | static __initdata char *victim; |
124 | static __initdata unsigned count; |
125 | static __initdata loff_t this_header, next_header; |
126 | |
127 | static __initdata int dry_run; |
128 | |
129 | static inline void eat(unsigned n) |
130 | { |
131 | victim += n; |
132 | this_header += n; |
133 | count -= n; |
134 | } |
135 | |
136 | #define N_ALIGN(len) ((((len) + 1) & ~3) + 2) |
137 | |
138 | static __initdata char *collected; |
139 | static __initdata int remains; |
140 | static __initdata char *collect; |
141 | |
142 | static void __init read_into(char *buf, unsigned size, enum state next) |
143 | { |
144 | if (count >= size) { |
145 | collected = victim; |
146 | eat(size); |
147 | state = next; |
148 | } else { |
149 | collect = collected = buf; |
150 | remains = size; |
151 | next_state = next; |
152 | state = Collect; |
153 | } |
154 | } |
155 | |
156 | static __initdata char *header_buf, *symlink_buf, *name_buf; |
157 | |
158 | static int __init do_start(void) |
159 | { |
160 | read_into(header_buf, 110, GotHeader); |
161 | return 0; |
162 | } |
163 | |
164 | static int __init do_collect(void) |
165 | { |
166 | unsigned n = remains; |
167 | if (count < n) |
168 | n = count; |
169 | memcpy(collect, victim, n); |
170 | eat(n); |
171 | collect += n; |
172 | if ((remains -= n) != 0) |
173 | return 1; |
174 | state = next_state; |
175 | return 0; |
176 | } |
177 | |
178 | static int __init do_header(void) |
179 | { |
180 | if (memcmp(collected, "070701", 6)) { |
181 | error("no cpio magic"); |
182 | return 1; |
183 | } |
184 | parse_header(collected); |
185 | next_header = this_header + N_ALIGN(name_len) + body_len; |
186 | next_header = (next_header + 3) & ~3; |
187 | if (dry_run) { |
188 | read_into(name_buf, N_ALIGN(name_len), GotName); |
189 | return 0; |
190 | } |
191 | state = SkipIt; |
192 | if (name_len <= 0 || name_len > PATH_MAX) |
193 | return 0; |
194 | if (S_ISLNK(mode)) { |
195 | if (body_len > PATH_MAX) |
196 | return 0; |
197 | collect = collected = symlink_buf; |
198 | remains = N_ALIGN(name_len) + body_len; |
199 | next_state = GotSymlink; |
200 | state = Collect; |
201 | return 0; |
202 | } |
203 | if (S_ISREG(mode) || !body_len) |
204 | read_into(name_buf, N_ALIGN(name_len), GotName); |
205 | return 0; |
206 | } |
207 | |
208 | static int __init do_skip(void) |
209 | { |
210 | if (this_header + count < next_header) { |
211 | eat(count); |
212 | return 1; |
213 | } else { |
214 | eat(next_header - this_header); |
215 | state = next_state; |
216 | return 0; |
217 | } |
218 | } |
219 | |
220 | static int __init do_reset(void) |
221 | { |
222 | while(count && *victim == '\0') |
223 | eat(1); |
224 | if (count && (this_header & 3)) |
225 | error("broken padding"); |
226 | return 1; |
227 | } |
228 | |
229 | static int __init maybe_link(void) |
230 | { |
231 | if (nlink >= 2) { |
232 | char *old = find_link(major, minor, ino, collected); |
233 | if (old) |
234 | return (sys_link(old, collected) < 0) ? -1 : 1; |
235 | } |
236 | return 0; |
237 | } |
238 | |
239 | static __initdata int wfd; |
240 | |
241 | static int __init do_name(void) |
242 | { |
243 | state = SkipIt; |
244 | next_state = Reset; |
245 | if (strcmp(collected, "TRAILER!!!") == 0) { |
246 | free_hash(); |
247 | return 0; |
248 | } |
249 | if (dry_run) |
250 | return 0; |
251 | if (S_ISREG(mode)) { |
252 | if (maybe_link() >= 0) { |
253 | wfd = sys_open(collected, O_WRONLY|O_CREAT, mode); |
254 | if (wfd >= 0) { |
255 | sys_fchown(wfd, uid, gid); |
256 | sys_fchmod(wfd, mode); |
257 | state = CopyFile; |
258 | } |
259 | } |
260 | } else if (S_ISDIR(mode)) { |
261 | sys_mkdir(collected, mode); |
262 | sys_chown(collected, uid, gid); |
263 | sys_chmod(collected, mode); |
264 | } else if (S_ISBLK(mode) || S_ISCHR(mode) || |
265 | S_ISFIFO(mode) || S_ISSOCK(mode)) { |
266 | if (maybe_link() == 0) { |
267 | sys_mknod(collected, mode, rdev); |
268 | sys_chown(collected, uid, gid); |
269 | sys_chmod(collected, mode); |
270 | } |
271 | } |
272 | return 0; |
273 | } |
274 | |
275 | static int __init do_copy(void) |
276 | { |
277 | if (count >= body_len) { |
278 | sys_write(wfd, victim, body_len); |
279 | sys_close(wfd); |
280 | eat(body_len); |
281 | state = SkipIt; |
282 | return 0; |
283 | } else { |
284 | sys_write(wfd, victim, count); |
285 | body_len -= count; |
286 | eat(count); |
287 | return 1; |
288 | } |
289 | } |
290 | |
291 | static int __init do_symlink(void) |
292 | { |
293 | collected[N_ALIGN(name_len) + body_len] = '\0'; |
294 | sys_symlink(collected + N_ALIGN(name_len), collected); |
295 | sys_lchown(collected, uid, gid); |
296 | state = SkipIt; |
297 | next_state = Reset; |
298 | return 0; |
299 | } |
300 | |
301 | static __initdata int (*actions[])(void) = { |
302 | [Start] = do_start, |
303 | [Collect] = do_collect, |
304 | [GotHeader] = do_header, |
305 | [SkipIt] = do_skip, |
306 | [GotName] = do_name, |
307 | [CopyFile] = do_copy, |
308 | [GotSymlink] = do_symlink, |
309 | [Reset] = do_reset, |
310 | }; |
311 | |
312 | static int __init write_buffer(char *buf, unsigned len) |
313 | { |
314 | count = len; |
315 | victim = buf; |
316 | |
317 | while (!actions[state]()) |
318 | ; |
319 | return len - count; |
320 | } |
321 | |
322 | static void __init flush_buffer(char *buf, unsigned len) |
323 | { |
324 | int written; |
325 | if (message) |
326 | return; |
327 | while ((written = write_buffer(buf, len)) < len && !message) { |
328 | char c = buf[written]; |
329 | if (c == '0') { |
330 | buf += written; |
331 | len -= written; |
332 | state = Start; |
333 | } else if (c == 0) { |
334 | buf += written; |
335 | len -= written; |
336 | state = Reset; |
337 | } else |
338 | error("junk in compressed archive"); |
339 | } |
340 | } |
341 | |
342 | /* |
343 | * gzip declarations |
344 | */ |
345 | |
346 | #define OF(args) args |
347 | |
348 | #ifndef memzero |
349 | #define memzero(s, n) memset ((s), 0, (n)) |
350 | #endif |
351 | |
352 | typedef unsigned char uch; |
353 | typedef unsigned short ush; |
354 | typedef unsigned long ulg; |
355 | |
356 | #define WSIZE 0x8000 /* window size--must be a power of two, and */ |
357 | /* at least 32K for zip's deflate method */ |
358 | |
359 | static uch *inbuf; |
360 | static uch *window; |
361 | |
362 | static unsigned insize; /* valid bytes in inbuf */ |
363 | static unsigned inptr; /* index of next byte to be processed in inbuf */ |
364 | static unsigned outcnt; /* bytes in output buffer */ |
365 | static long bytes_out; |
366 | |
367 | #define get_byte() (inptr < insize ? inbuf[inptr++] : -1) |
368 | |
369 | /* Diagnostic functions (stubbed out) */ |
370 | #define Assert(cond,msg) |
371 | #define Trace(x) |
372 | #define Tracev(x) |
373 | #define Tracevv(x) |
374 | #define Tracec(c,x) |
375 | #define Tracecv(c,x) |
376 | |
377 | #define STATIC static |
378 | #define INIT __init |
379 | |
380 | static void __init flush_window(void); |
381 | static void __init error(char *m); |
382 | static void __init gzip_mark(void **); |
383 | static void __init gzip_release(void **); |
384 | |
385 | #include "../lib/inflate.c" |
386 | |
387 | static void __init gzip_mark(void **ptr) |
388 | { |
389 | } |
390 | |
391 | static void __init gzip_release(void **ptr) |
392 | { |
393 | } |
394 | |
395 | /* =========================================================================== |
396 | * Write the output window window[0..outcnt-1] and update crc and bytes_out. |
397 | * (Used for the decompressed data only.) |
398 | */ |
399 | static void __init flush_window(void) |
400 | { |
401 | ulg c = crc; /* temporary variable */ |
402 | unsigned n; |
403 | uch *in, ch; |
404 | |
405 | flush_buffer(window, outcnt); |
406 | in = window; |
407 | for (n = 0; n < outcnt; n++) { |
408 | ch = *in++; |
409 | c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8); |
410 | } |
411 | crc = c; |
412 | bytes_out += (ulg)outcnt; |
413 | outcnt = 0; |
414 | } |
415 | |
416 | static char * __init unpack_to_rootfs(char *buf, unsigned len, int check_only) |
417 | { |
418 | int written; |
419 | dry_run = check_only; |
420 | header_buf = malloc(110); |
421 | symlink_buf = malloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1); |
422 | name_buf = malloc(N_ALIGN(PATH_MAX)); |
423 | window = malloc(WSIZE); |
424 | if (!window || !header_buf || !symlink_buf || !name_buf) |
425 | panic("can't allocate buffers"); |
426 | state = Start; |
427 | this_header = 0; |
428 | message = NULL; |
429 | while (!message && len) { |
430 | loff_t saved_offset = this_header; |
431 | if (*buf == '0' && !(this_header & 3)) { |
432 | state = Start; |
433 | written = write_buffer(buf, len); |
434 | buf += written; |
435 | len -= written; |
436 | continue; |
437 | } |
438 | if (!*buf) { |
439 | buf++; |
440 | len--; |
441 | this_header++; |
442 | continue; |
443 | } |
444 | this_header = 0; |
445 | insize = len; |
446 | inbuf = buf; |
447 | inptr = 0; |
448 | outcnt = 0; /* bytes in output buffer */ |
449 | bytes_out = 0; |
450 | crc = (ulg)0xffffffffL; /* shift register contents */ |
451 | makecrc(); |
452 | gunzip(); |
453 | if (state != Reset) |
454 | error("junk in gzipped archive"); |
455 | this_header = saved_offset + inptr; |
456 | buf += inptr; |
457 | len -= inptr; |
458 | } |
459 | free(window); |
460 | free(name_buf); |
461 | free(symlink_buf); |
462 | free(header_buf); |
463 | return message; |
464 | } |
465 | |
466 | extern char __initramfs_start[], __initramfs_end[]; |
467 | #ifdef CONFIG_BLK_DEV_INITRD |
468 | #include <linux/initrd.h> |
469 | #endif |
470 | |
471 | void __init populate_rootfs(void) |
472 | { |
473 | char *err = unpack_to_rootfs(__initramfs_start, |
474 | __initramfs_end - __initramfs_start, 0); |
475 | if (err) |
476 | panic(err); |
477 | #ifdef CONFIG_BLK_DEV_INITRD |
478 | if (initrd_start) { |
479 | int fd; |
480 | printk(KERN_INFO "checking if image is initramfs..."); |
481 | err = unpack_to_rootfs((char *)initrd_start, |
482 | initrd_end - initrd_start, 1); |
483 | if (!err) { |
484 | printk(" it is\n"); |
485 | unpack_to_rootfs((char *)initrd_start, |
486 | initrd_end - initrd_start, 0); |
487 | free_initrd_mem(initrd_start, initrd_end); |
488 | return; |
489 | } |
490 | printk("it isn't (%s); looks like an initrd\n", err); |
491 | fd = sys_open("/initrd.image", O_WRONLY|O_CREAT, 700); |
492 | if (fd >= 0) { |
493 | sys_write(fd, (char *)initrd_start, |
494 | initrd_end - initrd_start); |
495 | sys_close(fd); |
496 | free_initrd_mem(initrd_start, initrd_end); |
497 | } |
498 | } |
499 | #endif |
500 | } |