Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * JFFS -- Journaling Flash File System, Linux implementation. | |
3 | * | |
4 | * Copyright (C) 1999, 2000 Axis Communications, Inc. | |
5 | * | |
6 | * Created by Finn Hakansson <finn@axis.com>. | |
7 | * | |
8 | * This is free software; you can redistribute it and/or modify it | |
9 | * under the terms of the GNU General Public License as published by | |
10 | * the Free Software Foundation; either version 2 of the License, or | |
11 | * (at your option) any later version. | |
12 | * | |
13 | * $Id: intrep.c,v 1.102 2001/09/23 23:28:36 dwmw2 Exp $ | |
14 | * | |
15 | * Ported to Linux 2.3.x and MTD: | |
16 | * Copyright (C) 2000 Alexander Larsson (alex@cendio.se), Cendio Systems AB | |
17 | * | |
18 | */ | |
19 | ||
20 | /* This file contains the code for the internal structure of the | |
21 | Journaling Flash File System, JFFS. */ | |
22 | ||
23 | /* | |
24 | * Todo list: | |
25 | * | |
26 | * memcpy_to_flash() and memcpy_from_flash() functions. | |
27 | * | |
28 | * Implementation of hard links. | |
29 | * | |
30 | * Organize the source code in a better way. Against the VFS we could | |
31 | * have jffs_ext.c, and against the block device jffs_int.c. | |
32 | * A better file-internal organization too. | |
33 | * | |
34 | * A better checksum algorithm. | |
35 | * | |
36 | * Consider endianness stuff. ntohl() etc. | |
37 | * | |
38 | * Are we handling the atime, mtime, ctime members of the inode right? | |
39 | * | |
40 | * Remove some duplicated code. Take a look at jffs_write_node() and | |
41 | * jffs_rewrite_data() for instance. | |
42 | * | |
43 | * Implement more meaning of the nlink member in various data structures. | |
44 | * nlink could be used in conjunction with hard links for instance. | |
45 | * | |
46 | * Better memory management. Allocate data structures in larger chunks | |
47 | * if possible. | |
48 | * | |
49 | * If too much meta data is stored, a garbage collect should be issued. | |
50 | * We have experienced problems with too much meta data with for instance | |
51 | * log files. | |
52 | * | |
53 | * Improve the calls to jffs_ioctl(). We would like to retrieve more | |
54 | * information to be able to debug (or to supervise) JFFS during run-time. | |
55 | * | |
56 | */ | |
57 | ||
58 | #include <linux/config.h> | |
59 | #include <linux/types.h> | |
60 | #include <linux/slab.h> | |
61 | #include <linux/jffs.h> | |
62 | #include <linux/fs.h> | |
63 | #include <linux/stat.h> | |
64 | #include <linux/pagemap.h> | |
1eb0d670 | 65 | #include <linux/mutex.h> |
1da177e4 LT |
66 | #include <asm/byteorder.h> |
67 | #include <linux/smp_lock.h> | |
68 | #include <linux/time.h> | |
69 | #include <linux/ctype.h> | |
70 | ||
71 | #include "intrep.h" | |
72 | #include "jffs_fm.h" | |
73 | ||
74 | long no_jffs_node = 0; | |
75 | static long no_jffs_file = 0; | |
76 | #if defined(JFFS_MEMORY_DEBUG) && JFFS_MEMORY_DEBUG | |
77 | long no_jffs_control = 0; | |
78 | long no_jffs_raw_inode = 0; | |
79 | long no_jffs_node_ref = 0; | |
80 | long no_jffs_fm = 0; | |
81 | long no_jffs_fmcontrol = 0; | |
82 | long no_hash = 0; | |
83 | long no_name = 0; | |
84 | #endif | |
85 | ||
86 | static int jffs_scan_flash(struct jffs_control *c); | |
87 | static int jffs_update_file(struct jffs_file *f, struct jffs_node *node); | |
88 | static int jffs_build_file(struct jffs_file *f); | |
89 | static int jffs_free_file(struct jffs_file *f); | |
90 | static int jffs_free_node_list(struct jffs_file *f); | |
91 | static int jffs_garbage_collect_now(struct jffs_control *c); | |
92 | static int jffs_insert_file_into_hash(struct jffs_file *f); | |
93 | static int jffs_remove_redundant_nodes(struct jffs_file *f); | |
94 | ||
95 | /* Is there enough space on the flash? */ | |
96 | static inline int JFFS_ENOUGH_SPACE(struct jffs_control *c, __u32 space) | |
97 | { | |
98 | struct jffs_fmcontrol *fmc = c->fmc; | |
99 | ||
100 | while (1) { | |
101 | if ((fmc->flash_size - (fmc->used_size + fmc->dirty_size)) | |
102 | >= fmc->min_free_size + space) { | |
103 | return 1; | |
104 | } | |
105 | if (fmc->dirty_size < fmc->sector_size) | |
106 | return 0; | |
107 | ||
108 | if (jffs_garbage_collect_now(c)) { | |
109 | D1(printk("JFFS_ENOUGH_SPACE: jffs_garbage_collect_now() failed.\n")); | |
110 | return 0; | |
111 | } | |
112 | } | |
113 | } | |
114 | ||
115 | #if CONFIG_JFFS_FS_VERBOSE > 0 | |
116 | static __u8 | |
117 | flash_read_u8(struct mtd_info *mtd, loff_t from) | |
118 | { | |
119 | size_t retlen; | |
120 | __u8 ret; | |
121 | int res; | |
122 | ||
123 | res = MTD_READ(mtd, from, 1, &retlen, &ret); | |
124 | if (retlen != 1) { | |
125 | printk("Didn't read a byte in flash_read_u8(). Returned %d\n", res); | |
126 | return 0; | |
127 | } | |
128 | ||
129 | return ret; | |
130 | } | |
131 | ||
132 | static void | |
133 | jffs_hexdump(struct mtd_info *mtd, loff_t pos, int size) | |
134 | { | |
135 | char line[16]; | |
136 | int j = 0; | |
137 | ||
138 | while (size > 0) { | |
139 | int i; | |
140 | ||
141 | printk("%ld:", (long) pos); | |
142 | for (j = 0; j < 16; j++) { | |
143 | line[j] = flash_read_u8(mtd, pos++); | |
144 | } | |
145 | for (i = 0; i < j; i++) { | |
146 | if (!(i & 1)) { | |
147 | printk(" %.2x", line[i] & 0xff); | |
148 | } | |
149 | else { | |
150 | printk("%.2x", line[i] & 0xff); | |
151 | } | |
152 | } | |
153 | ||
154 | /* Print empty space */ | |
155 | for (; i < 16; i++) { | |
156 | if (!(i & 1)) { | |
157 | printk(" "); | |
158 | } | |
159 | else { | |
160 | printk(" "); | |
161 | } | |
162 | } | |
163 | printk(" "); | |
164 | ||
165 | for (i = 0; i < j; i++) { | |
166 | if (isgraph(line[i])) { | |
167 | printk("%c", line[i]); | |
168 | } | |
169 | else { | |
170 | printk("."); | |
171 | } | |
172 | } | |
173 | printk("\n"); | |
174 | size -= 16; | |
175 | } | |
176 | } | |
177 | ||
94c9eca2 AB |
178 | /* Print the contents of a node. */ |
179 | static void | |
180 | jffs_print_node(struct jffs_node *n) | |
181 | { | |
182 | D(printk("jffs_node: 0x%p\n", n)); | |
183 | D(printk("{\n")); | |
184 | D(printk(" 0x%08x, /* version */\n", n->version)); | |
185 | D(printk(" 0x%08x, /* data_offset */\n", n->data_offset)); | |
186 | D(printk(" 0x%08x, /* data_size */\n", n->data_size)); | |
187 | D(printk(" 0x%08x, /* removed_size */\n", n->removed_size)); | |
188 | D(printk(" 0x%08x, /* fm_offset */\n", n->fm_offset)); | |
189 | D(printk(" 0x%02x, /* name_size */\n", n->name_size)); | |
190 | D(printk(" 0x%p, /* fm, fm->offset: %u */\n", | |
191 | n->fm, (n->fm ? n->fm->offset : 0))); | |
192 | D(printk(" 0x%p, /* version_prev */\n", n->version_prev)); | |
193 | D(printk(" 0x%p, /* version_next */\n", n->version_next)); | |
194 | D(printk(" 0x%p, /* range_prev */\n", n->range_prev)); | |
195 | D(printk(" 0x%p, /* range_next */\n", n->range_next)); | |
196 | D(printk("}\n")); | |
197 | } | |
198 | ||
1da177e4 LT |
199 | #endif |
200 | ||
94c9eca2 AB |
201 | /* Print the contents of a raw inode. */ |
202 | static void | |
203 | jffs_print_raw_inode(struct jffs_raw_inode *raw_inode) | |
204 | { | |
205 | D(printk("jffs_raw_inode: inode number: %u\n", raw_inode->ino)); | |
206 | D(printk("{\n")); | |
207 | D(printk(" 0x%08x, /* magic */\n", raw_inode->magic)); | |
208 | D(printk(" 0x%08x, /* ino */\n", raw_inode->ino)); | |
209 | D(printk(" 0x%08x, /* pino */\n", raw_inode->pino)); | |
210 | D(printk(" 0x%08x, /* version */\n", raw_inode->version)); | |
211 | D(printk(" 0x%08x, /* mode */\n", raw_inode->mode)); | |
212 | D(printk(" 0x%04x, /* uid */\n", raw_inode->uid)); | |
213 | D(printk(" 0x%04x, /* gid */\n", raw_inode->gid)); | |
214 | D(printk(" 0x%08x, /* atime */\n", raw_inode->atime)); | |
215 | D(printk(" 0x%08x, /* mtime */\n", raw_inode->mtime)); | |
216 | D(printk(" 0x%08x, /* ctime */\n", raw_inode->ctime)); | |
217 | D(printk(" 0x%08x, /* offset */\n", raw_inode->offset)); | |
218 | D(printk(" 0x%08x, /* dsize */\n", raw_inode->dsize)); | |
219 | D(printk(" 0x%08x, /* rsize */\n", raw_inode->rsize)); | |
220 | D(printk(" 0x%02x, /* nsize */\n", raw_inode->nsize)); | |
221 | D(printk(" 0x%02x, /* nlink */\n", raw_inode->nlink)); | |
222 | D(printk(" 0x%02x, /* spare */\n", | |
223 | raw_inode->spare)); | |
224 | D(printk(" %u, /* rename */\n", | |
225 | raw_inode->rename)); | |
226 | D(printk(" %u, /* deleted */\n", | |
227 | raw_inode->deleted)); | |
228 | D(printk(" 0x%02x, /* accurate */\n", | |
229 | raw_inode->accurate)); | |
230 | D(printk(" 0x%08x, /* dchksum */\n", raw_inode->dchksum)); | |
231 | D(printk(" 0x%04x, /* nchksum */\n", raw_inode->nchksum)); | |
232 | D(printk(" 0x%04x, /* chksum */\n", raw_inode->chksum)); | |
233 | D(printk("}\n")); | |
234 | } | |
235 | ||
1da177e4 LT |
236 | #define flash_safe_acquire(arg) |
237 | #define flash_safe_release(arg) | |
238 | ||
239 | ||
240 | static int | |
241 | flash_safe_read(struct mtd_info *mtd, loff_t from, | |
242 | u_char *buf, size_t count) | |
243 | { | |
244 | size_t retlen; | |
245 | int res; | |
246 | ||
247 | D3(printk(KERN_NOTICE "flash_safe_read(%p, %08x, %p, %08x)\n", | |
248 | mtd, (unsigned int) from, buf, count)); | |
249 | ||
250 | res = MTD_READ(mtd, from, count, &retlen, buf); | |
251 | if (retlen != count) { | |
252 | panic("Didn't read all bytes in flash_safe_read(). Returned %d\n", res); | |
253 | } | |
254 | return res?res:retlen; | |
255 | } | |
256 | ||
257 | ||
258 | static __u32 | |
259 | flash_read_u32(struct mtd_info *mtd, loff_t from) | |
260 | { | |
261 | size_t retlen; | |
262 | __u32 ret; | |
263 | int res; | |
264 | ||
265 | res = MTD_READ(mtd, from, 4, &retlen, (unsigned char *)&ret); | |
266 | if (retlen != 4) { | |
267 | printk("Didn't read all bytes in flash_read_u32(). Returned %d\n", res); | |
268 | return 0; | |
269 | } | |
270 | ||
271 | return ret; | |
272 | } | |
273 | ||
274 | ||
275 | static int | |
276 | flash_safe_write(struct mtd_info *mtd, loff_t to, | |
277 | const u_char *buf, size_t count) | |
278 | { | |
279 | size_t retlen; | |
280 | int res; | |
281 | ||
282 | D3(printk(KERN_NOTICE "flash_safe_write(%p, %08x, %p, %08x)\n", | |
283 | mtd, (unsigned int) to, buf, count)); | |
284 | ||
285 | res = MTD_WRITE(mtd, to, count, &retlen, buf); | |
286 | if (retlen != count) { | |
287 | printk("Didn't write all bytes in flash_safe_write(). Returned %d\n", res); | |
288 | } | |
289 | return res?res:retlen; | |
290 | } | |
291 | ||
292 | ||
293 | static int | |
294 | flash_safe_writev(struct mtd_info *mtd, const struct kvec *vecs, | |
295 | unsigned long iovec_cnt, loff_t to) | |
296 | { | |
297 | size_t retlen, retlen_a; | |
298 | int i; | |
299 | int res; | |
300 | ||
301 | D3(printk(KERN_NOTICE "flash_safe_writev(%p, %08x, %p)\n", | |
302 | mtd, (unsigned int) to, vecs)); | |
303 | ||
304 | if (mtd->writev) { | |
305 | res = MTD_WRITEV(mtd, vecs, iovec_cnt, to, &retlen); | |
306 | return res ? res : retlen; | |
307 | } | |
308 | /* Not implemented writev. Repeatedly use write - on the not so | |
309 | unreasonable assumption that the mtd driver doesn't care how | |
310 | many write cycles we use. */ | |
311 | res=0; | |
312 | retlen=0; | |
313 | ||
314 | for (i=0; !res && i<iovec_cnt; i++) { | |
315 | res = MTD_WRITE(mtd, to, vecs[i].iov_len, &retlen_a, vecs[i].iov_base); | |
316 | if (retlen_a != vecs[i].iov_len) { | |
317 | printk("Didn't write all bytes in flash_safe_writev(). Returned %d\n", res); | |
318 | if (i != iovec_cnt-1) | |
319 | return -EIO; | |
320 | } | |
321 | /* If res is non-zero, retlen_a is undefined, but we don't | |
322 | care because in that case it's not going to be | |
323 | returned anyway. | |
324 | */ | |
325 | to += retlen_a; | |
326 | retlen += retlen_a; | |
327 | } | |
328 | return res?res:retlen; | |
329 | } | |
330 | ||
331 | ||
332 | static int | |
333 | flash_memset(struct mtd_info *mtd, loff_t to, | |
334 | const u_char c, size_t size) | |
335 | { | |
336 | static unsigned char pattern[64]; | |
337 | int i; | |
338 | ||
339 | /* fill up pattern */ | |
340 | ||
341 | for(i = 0; i < 64; i++) | |
342 | pattern[i] = c; | |
343 | ||
344 | /* write as many 64-byte chunks as we can */ | |
345 | ||
346 | while (size >= 64) { | |
347 | flash_safe_write(mtd, to, pattern, 64); | |
348 | size -= 64; | |
349 | to += 64; | |
350 | } | |
351 | ||
352 | /* and the rest */ | |
353 | ||
354 | if(size) | |
355 | flash_safe_write(mtd, to, pattern, size); | |
356 | ||
357 | return size; | |
358 | } | |
359 | ||
360 | ||
361 | static void | |
362 | intrep_erase_callback(struct erase_info *done) | |
363 | { | |
364 | wait_queue_head_t *wait_q; | |
365 | ||
366 | wait_q = (wait_queue_head_t *)done->priv; | |
367 | ||
368 | wake_up(wait_q); | |
369 | } | |
370 | ||
371 | ||
372 | static int | |
373 | flash_erase_region(struct mtd_info *mtd, loff_t start, | |
374 | size_t size) | |
375 | { | |
376 | struct erase_info *erase; | |
377 | DECLARE_WAITQUEUE(wait, current); | |
378 | wait_queue_head_t wait_q; | |
379 | ||
380 | erase = kmalloc(sizeof(struct erase_info), GFP_KERNEL); | |
381 | if (!erase) | |
382 | return -ENOMEM; | |
383 | ||
384 | init_waitqueue_head(&wait_q); | |
385 | ||
386 | erase->mtd = mtd; | |
387 | erase->callback = intrep_erase_callback; | |
388 | erase->addr = start; | |
389 | erase->len = size; | |
390 | erase->priv = (u_long)&wait_q; | |
391 | ||
392 | /* FIXME: Use TASK_INTERRUPTIBLE and deal with being interrupted */ | |
393 | set_current_state(TASK_UNINTERRUPTIBLE); | |
394 | add_wait_queue(&wait_q, &wait); | |
395 | ||
396 | if (MTD_ERASE(mtd, erase) < 0) { | |
397 | set_current_state(TASK_RUNNING); | |
398 | remove_wait_queue(&wait_q, &wait); | |
399 | kfree(erase); | |
400 | ||
401 | printk(KERN_WARNING "flash: erase of region [0x%lx, 0x%lx] " | |
402 | "totally failed\n", (long)start, (long)start + size); | |
403 | ||
404 | return -1; | |
405 | } | |
406 | ||
407 | schedule(); /* Wait for flash to finish. */ | |
408 | remove_wait_queue(&wait_q, &wait); | |
409 | ||
410 | kfree(erase); | |
411 | ||
412 | return 0; | |
413 | } | |
414 | ||
415 | /* This routine calculates checksums in JFFS. */ | |
416 | static __u32 | |
417 | jffs_checksum(const void *data, int size) | |
418 | { | |
419 | __u32 sum = 0; | |
420 | __u8 *ptr = (__u8 *)data; | |
421 | while (size-- > 0) { | |
422 | sum += *ptr++; | |
423 | } | |
424 | D3(printk(", result: 0x%08x\n", sum)); | |
425 | return sum; | |
426 | } | |
427 | ||
428 | ||
429 | static int | |
430 | jffs_checksum_flash(struct mtd_info *mtd, loff_t start, int size, __u32 *result) | |
431 | { | |
432 | __u32 sum = 0; | |
433 | loff_t ptr = start; | |
434 | __u8 *read_buf; | |
435 | int i, length; | |
436 | ||
437 | /* Allocate read buffer */ | |
438 | read_buf = (__u8 *) kmalloc (sizeof(__u8) * 4096, GFP_KERNEL); | |
439 | if (!read_buf) { | |
440 | printk(KERN_NOTICE "kmalloc failed in jffs_checksum_flash()\n"); | |
441 | return -ENOMEM; | |
442 | } | |
443 | /* Loop until checksum done */ | |
444 | while (size) { | |
445 | /* Get amount of data to read */ | |
446 | if (size < 4096) | |
447 | length = size; | |
448 | else | |
449 | length = 4096; | |
450 | ||
451 | /* Perform flash read */ | |
452 | D3(printk(KERN_NOTICE "jffs_checksum_flash\n")); | |
453 | flash_safe_read(mtd, ptr, &read_buf[0], length); | |
454 | ||
455 | /* Compute checksum */ | |
456 | for (i=0; i < length ; i++) | |
457 | sum += read_buf[i]; | |
458 | ||
459 | /* Update pointer and size */ | |
460 | size -= length; | |
461 | ptr += length; | |
462 | } | |
463 | ||
464 | /* Free read buffer */ | |
f99d49ad | 465 | kfree(read_buf); |
1da177e4 LT |
466 | |
467 | /* Return result */ | |
468 | D3(printk("checksum result: 0x%08x\n", sum)); | |
469 | *result = sum; | |
470 | return 0; | |
471 | } | |
472 | ||
473 | static __inline__ void jffs_fm_write_lock(struct jffs_fmcontrol *fmc) | |
474 | { | |
475 | // down(&fmc->wlock); | |
476 | } | |
477 | ||
478 | static __inline__ void jffs_fm_write_unlock(struct jffs_fmcontrol *fmc) | |
479 | { | |
480 | // up(&fmc->wlock); | |
481 | } | |
482 | ||
483 | ||
484 | /* Create and initialize a new struct jffs_file. */ | |
485 | static struct jffs_file * | |
486 | jffs_create_file(struct jffs_control *c, | |
487 | const struct jffs_raw_inode *raw_inode) | |
488 | { | |
489 | struct jffs_file *f; | |
490 | ||
491 | if (!(f = (struct jffs_file *)kmalloc(sizeof(struct jffs_file), | |
492 | GFP_KERNEL))) { | |
493 | D(printk("jffs_create_file(): Failed!\n")); | |
494 | return NULL; | |
495 | } | |
496 | no_jffs_file++; | |
497 | memset(f, 0, sizeof(struct jffs_file)); | |
498 | f->ino = raw_inode->ino; | |
499 | f->pino = raw_inode->pino; | |
500 | f->nlink = raw_inode->nlink; | |
501 | f->deleted = raw_inode->deleted; | |
502 | f->c = c; | |
503 | ||
504 | return f; | |
505 | } | |
506 | ||
507 | ||
508 | /* Build a control block for the file system. */ | |
509 | static struct jffs_control * | |
510 | jffs_create_control(struct super_block *sb) | |
511 | { | |
512 | struct jffs_control *c; | |
513 | register int s = sizeof(struct jffs_control); | |
514 | int i; | |
515 | D(char *t = 0); | |
516 | ||
517 | D2(printk("jffs_create_control()\n")); | |
518 | ||
519 | if (!(c = (struct jffs_control *)kmalloc(s, GFP_KERNEL))) { | |
520 | goto fail_control; | |
521 | } | |
522 | DJM(no_jffs_control++); | |
523 | c->root = NULL; | |
524 | c->gc_task = NULL; | |
525 | c->hash_len = JFFS_HASH_SIZE; | |
526 | s = sizeof(struct list_head) * c->hash_len; | |
527 | if (!(c->hash = (struct list_head *)kmalloc(s, GFP_KERNEL))) { | |
528 | goto fail_hash; | |
529 | } | |
530 | DJM(no_hash++); | |
531 | for (i = 0; i < c->hash_len; i++) | |
532 | INIT_LIST_HEAD(&c->hash[i]); | |
533 | if (!(c->fmc = jffs_build_begin(c, MINOR(sb->s_dev)))) { | |
534 | goto fail_fminit; | |
535 | } | |
536 | c->next_ino = JFFS_MIN_INO + 1; | |
537 | c->delete_list = (struct jffs_delete_list *) 0; | |
538 | return c; | |
539 | ||
540 | fail_fminit: | |
541 | D(t = "c->fmc"); | |
542 | fail_hash: | |
543 | kfree(c); | |
544 | DJM(no_jffs_control--); | |
545 | D(t = t ? t : "c->hash"); | |
546 | fail_control: | |
547 | D(t = t ? t : "control"); | |
548 | D(printk("jffs_create_control(): Allocation failed: (%s)\n", t)); | |
549 | return (struct jffs_control *)0; | |
550 | } | |
551 | ||
552 | ||
553 | /* Clean up all data structures associated with the file system. */ | |
554 | void | |
555 | jffs_cleanup_control(struct jffs_control *c) | |
556 | { | |
557 | D2(printk("jffs_cleanup_control()\n")); | |
558 | ||
559 | if (!c) { | |
560 | D(printk("jffs_cleanup_control(): c == NULL !!!\n")); | |
561 | return; | |
562 | } | |
563 | ||
564 | while (c->delete_list) { | |
565 | struct jffs_delete_list *delete_list_element; | |
566 | delete_list_element = c->delete_list; | |
567 | c->delete_list = c->delete_list->next; | |
568 | kfree(delete_list_element); | |
569 | } | |
570 | ||
571 | /* Free all files and nodes. */ | |
572 | if (c->hash) { | |
573 | jffs_foreach_file(c, jffs_free_node_list); | |
574 | jffs_foreach_file(c, jffs_free_file); | |
575 | kfree(c->hash); | |
576 | DJM(no_hash--); | |
577 | } | |
578 | jffs_cleanup_fmcontrol(c->fmc); | |
579 | kfree(c); | |
580 | DJM(no_jffs_control--); | |
581 | D3(printk("jffs_cleanup_control(): Leaving...\n")); | |
582 | } | |
583 | ||
584 | ||
585 | /* This function adds a virtual root node to the in-RAM representation. | |
586 | Called by jffs_build_fs(). */ | |
587 | static int | |
588 | jffs_add_virtual_root(struct jffs_control *c) | |
589 | { | |
590 | struct jffs_file *root; | |
591 | struct jffs_node *node; | |
592 | ||
593 | D2(printk("jffs_add_virtual_root(): " | |
594 | "Creating a virtual root directory.\n")); | |
595 | ||
596 | if (!(root = (struct jffs_file *)kmalloc(sizeof(struct jffs_file), | |
597 | GFP_KERNEL))) { | |
598 | return -ENOMEM; | |
599 | } | |
600 | no_jffs_file++; | |
601 | if (!(node = jffs_alloc_node())) { | |
602 | kfree(root); | |
603 | no_jffs_file--; | |
604 | return -ENOMEM; | |
605 | } | |
606 | DJM(no_jffs_node++); | |
607 | memset(node, 0, sizeof(struct jffs_node)); | |
608 | node->ino = JFFS_MIN_INO; | |
609 | memset(root, 0, sizeof(struct jffs_file)); | |
610 | root->ino = JFFS_MIN_INO; | |
611 | root->mode = S_IFDIR | S_IRWXU | S_IRGRP | |
612 | | S_IXGRP | S_IROTH | S_IXOTH; | |
613 | root->atime = root->mtime = root->ctime = get_seconds(); | |
614 | root->nlink = 1; | |
615 | root->c = c; | |
616 | root->version_head = root->version_tail = node; | |
617 | jffs_insert_file_into_hash(root); | |
618 | return 0; | |
619 | } | |
620 | ||
621 | ||
622 | /* This is where the file system is built and initialized. */ | |
623 | int | |
624 | jffs_build_fs(struct super_block *sb) | |
625 | { | |
626 | struct jffs_control *c; | |
627 | int err = 0; | |
628 | ||
629 | D2(printk("jffs_build_fs()\n")); | |
630 | ||
631 | if (!(c = jffs_create_control(sb))) { | |
632 | return -ENOMEM; | |
633 | } | |
634 | c->building_fs = 1; | |
635 | c->sb = sb; | |
636 | if ((err = jffs_scan_flash(c)) < 0) { | |
637 | if(err == -EAGAIN){ | |
638 | /* scan_flash() wants us to try once more. A flipping | |
639 | bits sector was detect in the middle of the scan flash. | |
640 | Clean up old allocated memory before going in. | |
641 | */ | |
642 | D1(printk("jffs_build_fs: Cleaning up all control structures," | |
643 | " reallocating them and trying mount again.\n")); | |
644 | jffs_cleanup_control(c); | |
645 | if (!(c = jffs_create_control(sb))) { | |
646 | return -ENOMEM; | |
647 | } | |
648 | c->building_fs = 1; | |
649 | c->sb = sb; | |
650 | ||
651 | if ((err = jffs_scan_flash(c)) < 0) { | |
652 | goto jffs_build_fs_fail; | |
653 | } | |
654 | }else{ | |
655 | goto jffs_build_fs_fail; | |
656 | } | |
657 | } | |
658 | ||
659 | /* Add a virtual root node if no one exists. */ | |
660 | if (!jffs_find_file(c, JFFS_MIN_INO)) { | |
661 | if ((err = jffs_add_virtual_root(c)) < 0) { | |
662 | goto jffs_build_fs_fail; | |
663 | } | |
664 | } | |
665 | ||
666 | while (c->delete_list) { | |
667 | struct jffs_file *f; | |
668 | struct jffs_delete_list *delete_list_element; | |
669 | ||
670 | if ((f = jffs_find_file(c, c->delete_list->ino))) { | |
671 | f->deleted = 1; | |
672 | } | |
673 | delete_list_element = c->delete_list; | |
674 | c->delete_list = c->delete_list->next; | |
675 | kfree(delete_list_element); | |
676 | } | |
677 | ||
678 | /* Remove deleted nodes. */ | |
679 | if ((err = jffs_foreach_file(c, jffs_possibly_delete_file)) < 0) { | |
680 | printk(KERN_ERR "JFFS: Failed to remove deleted nodes.\n"); | |
681 | goto jffs_build_fs_fail; | |
682 | } | |
683 | /* Remove redundant nodes. (We are not interested in the | |
684 | return value in this case.) */ | |
685 | jffs_foreach_file(c, jffs_remove_redundant_nodes); | |
686 | /* Try to build a tree from all the nodes. */ | |
687 | if ((err = jffs_foreach_file(c, jffs_insert_file_into_tree)) < 0) { | |
688 | printk("JFFS: Failed to build tree.\n"); | |
689 | goto jffs_build_fs_fail; | |
690 | } | |
691 | /* Compute the sizes of all files in the filesystem. Adjust if | |
692 | necessary. */ | |
693 | if ((err = jffs_foreach_file(c, jffs_build_file)) < 0) { | |
694 | printk("JFFS: Failed to build file system.\n"); | |
695 | goto jffs_build_fs_fail; | |
696 | } | |
697 | sb->s_fs_info = (void *)c; | |
698 | c->building_fs = 0; | |
699 | ||
700 | D1(jffs_print_hash_table(c)); | |
701 | D1(jffs_print_tree(c->root, 0)); | |
702 | ||
703 | return 0; | |
704 | ||
705 | jffs_build_fs_fail: | |
706 | jffs_cleanup_control(c); | |
707 | return err; | |
708 | } /* jffs_build_fs() */ | |
709 | ||
710 | ||
711 | /* | |
712 | This checks for sectors that were being erased in their previous | |
713 | lifetimes and for some reason or the other (power fail etc.), | |
714 | the erase cycles never completed. | |
715 | As the flash array would have reverted back to read status, | |
716 | these sectors are detected by the symptom of the "flipping bits", | |
717 | i.e. bits being read back differently from the same location in | |
718 | flash if read multiple times. | |
719 | The only solution to this is to re-erase the entire | |
720 | sector. | |
721 | Unfortunately detecting "flipping bits" is not a simple exercise | |
722 | as a bit may be read back at 1 or 0 depending on the alignment | |
723 | of the stars in the universe. | |
724 | The level of confidence is in direct proportion to the number of | |
725 | scans done. By power fail testing I (Vipin) have been able to | |
726 | proove that reading twice is not enough. | |
727 | Maybe 4 times? Change NUM_REREADS to a higher number if you want | |
728 | a (even) higher degree of confidence in your mount process. | |
729 | A higher number would of course slow down your mount. | |
730 | */ | |
731 | static int check_partly_erased_sectors(struct jffs_fmcontrol *fmc){ | |
732 | ||
733 | #define NUM_REREADS 4 /* see note above */ | |
734 | #define READ_AHEAD_BYTES 4096 /* must be a multiple of 4, | |
735 | usually set to kernel page size */ | |
736 | ||
737 | __u8 *read_buf1; | |
738 | __u8 *read_buf2; | |
739 | ||
740 | int err = 0; | |
741 | int retlen; | |
742 | int i; | |
743 | int cnt; | |
744 | __u32 offset; | |
745 | loff_t pos = 0; | |
746 | loff_t end = fmc->flash_size; | |
747 | ||
748 | ||
749 | /* Allocate read buffers */ | |
750 | read_buf1 = (__u8 *) kmalloc (sizeof(__u8) * READ_AHEAD_BYTES, GFP_KERNEL); | |
751 | if (!read_buf1) | |
752 | return -ENOMEM; | |
753 | ||
754 | read_buf2 = (__u8 *) kmalloc (sizeof(__u8) * READ_AHEAD_BYTES, GFP_KERNEL); | |
755 | if (!read_buf2) { | |
756 | kfree(read_buf1); | |
757 | return -ENOMEM; | |
758 | } | |
759 | ||
760 | CHECK_NEXT: | |
761 | while(pos < end){ | |
762 | ||
763 | D1(printk("check_partly_erased_sector():checking sector which contains" | |
764 | " offset 0x%x for flipping bits..\n", (__u32)pos)); | |
765 | ||
766 | retlen = flash_safe_read(fmc->mtd, pos, | |
767 | &read_buf1[0], READ_AHEAD_BYTES); | |
768 | retlen &= ~3; | |
769 | ||
770 | for(cnt = 0; cnt < NUM_REREADS; cnt++){ | |
771 | (void)flash_safe_read(fmc->mtd, pos, | |
772 | &read_buf2[0], READ_AHEAD_BYTES); | |
773 | ||
774 | for (i=0 ; i < retlen ; i+=4) { | |
775 | /* buffers MUST match, double word for word! */ | |
776 | if(*((__u32 *) &read_buf1[i]) != | |
777 | *((__u32 *) &read_buf2[i]) | |
778 | ){ | |
779 | /* flipping bits detected, time to erase sector */ | |
780 | /* This will help us log some statistics etc. */ | |
781 | D1(printk("Flipping bits detected in re-read round:%i of %i\n", | |
782 | cnt, NUM_REREADS)); | |
783 | D1(printk("check_partly_erased_sectors:flipping bits detected" | |
784 | " @offset:0x%x(0x%x!=0x%x)\n", | |
785 | (__u32)pos+i, *((__u32 *) &read_buf1[i]), | |
786 | *((__u32 *) &read_buf2[i]))); | |
787 | ||
788 | /* calculate start of present sector */ | |
789 | offset = (((__u32)pos+i)/(__u32)fmc->sector_size) * (__u32)fmc->sector_size; | |
790 | ||
791 | D1(printk("check_partly_erased_sector():erasing sector starting 0x%x.\n", | |
792 | offset)); | |
793 | ||
794 | if (flash_erase_region(fmc->mtd, | |
795 | offset, fmc->sector_size) < 0) { | |
796 | printk(KERN_ERR "JFFS: Erase of flash failed. " | |
797 | "offset = %u, erase_size = %d\n", | |
798 | offset , fmc->sector_size); | |
799 | ||
800 | err = -EIO; | |
801 | goto returnBack; | |
802 | ||
803 | }else{ | |
804 | D1(printk("JFFS: Erase of flash sector @0x%x successful.\n", | |
805 | offset)); | |
806 | /* skip ahead to the next sector */ | |
807 | pos = (((__u32)pos+i)/(__u32)fmc->sector_size) * (__u32)fmc->sector_size; | |
808 | pos += fmc->sector_size; | |
809 | goto CHECK_NEXT; | |
810 | } | |
811 | } | |
812 | } | |
813 | } | |
814 | pos += READ_AHEAD_BYTES; | |
815 | } | |
816 | ||
817 | returnBack: | |
818 | kfree(read_buf1); | |
819 | kfree(read_buf2); | |
820 | ||
821 | D2(printk("check_partly_erased_sector():Done checking all sectors till offset 0x%x for flipping bits.\n", | |
822 | (__u32)pos)); | |
823 | ||
824 | return err; | |
825 | ||
826 | }/* end check_partly_erased_sectors() */ | |
827 | ||
828 | ||
829 | ||
830 | /* Scan the whole flash memory in order to find all nodes in the | |
831 | file systems. */ | |
832 | static int | |
833 | jffs_scan_flash(struct jffs_control *c) | |
834 | { | |
835 | char name[JFFS_MAX_NAME_LEN + 2]; | |
836 | struct jffs_raw_inode raw_inode; | |
837 | struct jffs_node *node = NULL; | |
838 | struct jffs_fmcontrol *fmc = c->fmc; | |
839 | __u32 checksum; | |
840 | __u8 tmp_accurate; | |
841 | __u16 tmp_chksum; | |
842 | __u32 deleted_file; | |
843 | loff_t pos = 0; | |
844 | loff_t start; | |
845 | loff_t test_start; | |
846 | loff_t end = fmc->flash_size; | |
847 | __u8 *read_buf; | |
848 | int i, len, retlen; | |
849 | __u32 offset; | |
850 | ||
851 | __u32 free_chunk_size1; | |
852 | __u32 free_chunk_size2; | |
853 | ||
854 | ||
855 | #define NUMFREEALLOWED 2 /* 2 chunks of at least erase size space allowed */ | |
856 | int num_free_space = 0; /* Flag err if more than TWO | |
857 | free blocks found. This is NOT allowed | |
858 | by the current jffs design. | |
859 | */ | |
860 | int num_free_spc_not_accp = 0; /* For debugging purposed keep count | |
861 | of how much free space was rejected and | |
862 | marked dirty | |
863 | */ | |
864 | ||
865 | D1(printk("jffs_scan_flash(): start pos = 0x%lx, end = 0x%lx\n", | |
866 | (long)pos, (long)end)); | |
867 | ||
868 | flash_safe_acquire(fmc->mtd); | |
869 | ||
870 | /* | |
871 | check and make sure that any sector does not suffer | |
872 | from the "partly erased, bit flipping syndrome" (TM Vipin :) | |
873 | If so, offending sectors will be erased. | |
874 | */ | |
875 | if(check_partly_erased_sectors(fmc) < 0){ | |
876 | ||
877 | flash_safe_release(fmc->mtd); | |
878 | return -EIO; /* bad, bad, bad error. Cannot continue.*/ | |
879 | } | |
880 | ||
881 | /* Allocate read buffer */ | |
882 | read_buf = (__u8 *) kmalloc (sizeof(__u8) * 4096, GFP_KERNEL); | |
883 | if (!read_buf) { | |
884 | flash_safe_release(fmc->mtd); | |
885 | return -ENOMEM; | |
886 | } | |
887 | ||
888 | /* Start the scan. */ | |
889 | while (pos < end) { | |
890 | deleted_file = 0; | |
891 | ||
892 | /* Remember the position from where we started this scan. */ | |
893 | start = pos; | |
894 | ||
895 | switch (flash_read_u32(fmc->mtd, pos)) { | |
896 | case JFFS_EMPTY_BITMASK: | |
897 | /* We have found 0xffffffff at this position. We have to | |
898 | scan the rest of the flash till the end or till | |
899 | something else than 0xffffffff is found. | |
900 | Keep going till we do not find JFFS_EMPTY_BITMASK | |
901 | anymore */ | |
902 | ||
903 | D1(printk("jffs_scan_flash(): 0xffffffff at pos 0x%lx.\n", | |
904 | (long)pos)); | |
905 | ||
906 | while(pos < end){ | |
907 | ||
908 | len = end - pos < 4096 ? end - pos : 4096; | |
909 | ||
910 | retlen = flash_safe_read(fmc->mtd, pos, | |
911 | &read_buf[0], len); | |
912 | ||
913 | retlen &= ~3; | |
914 | ||
915 | for (i=0 ; i < retlen ; i+=4, pos += 4) { | |
916 | if(*((__u32 *) &read_buf[i]) != | |
917 | JFFS_EMPTY_BITMASK) | |
918 | break; | |
919 | } | |
920 | if (i == retlen) | |
921 | continue; | |
922 | else | |
923 | break; | |
924 | } | |
925 | ||
926 | D1(printk("jffs_scan_flash():0xffffffff ended at pos 0x%lx.\n", | |
927 | (long)pos)); | |
928 | ||
929 | /* If some free space ends in the middle of a sector, | |
930 | treat it as dirty rather than clean. | |
931 | This is to handle the case where one thread | |
932 | allocated space for a node, but didn't get to | |
933 | actually _write_ it before power was lost, leaving | |
934 | a gap in the log. Shifting all node writes into | |
935 | a single kernel thread will fix the original problem. | |
936 | */ | |
937 | if ((__u32) pos % fmc->sector_size) { | |
938 | /* If there was free space in previous | |
939 | sectors, don't mark that dirty too - | |
940 | only from the beginning of this sector | |
941 | (or from start) | |
942 | */ | |
943 | ||
944 | test_start = pos & ~(fmc->sector_size-1); /* end of last sector */ | |
945 | ||
946 | if (start < test_start) { | |
947 | ||
948 | /* free space started in the previous sector! */ | |
949 | ||
950 | if((num_free_space < NUMFREEALLOWED) && | |
951 | ((unsigned int)(test_start - start) >= fmc->sector_size)){ | |
952 | ||
953 | /* | |
954 | Count it in if we are still under NUMFREEALLOWED *and* it is | |
955 | at least 1 erase sector in length. This will keep us from | |
956 | picking any little ole' space as "free". | |
957 | */ | |
958 | ||
959 | D1(printk("Reducing end of free space to 0x%x from 0x%x\n", | |
960 | (unsigned int)test_start, (unsigned int)pos)); | |
961 | ||
962 | D1(printk("Free space accepted: Starting 0x%x for 0x%x bytes\n", | |
963 | (unsigned int) start, | |
964 | (unsigned int)(test_start - start))); | |
965 | ||
966 | /* below, space from "start" to "pos" will be marked dirty. */ | |
967 | start = test_start; | |
968 | ||
969 | /* Being in here means that we have found at least an entire | |
970 | erase sector size of free space ending on a sector boundary. | |
971 | Keep track of free spaces accepted. | |
972 | */ | |
973 | num_free_space++; | |
974 | }else{ | |
975 | num_free_spc_not_accp++; | |
976 | D1(printk("Free space (#%i) found but *Not* accepted: Starting" | |
977 | " 0x%x for 0x%x bytes\n", | |
978 | num_free_spc_not_accp, (unsigned int)start, | |
979 | (unsigned int)((unsigned int)(pos & ~(fmc->sector_size-1)) - (unsigned int)start))); | |
980 | ||
981 | } | |
982 | ||
983 | } | |
984 | if((((__u32)(pos - start)) != 0)){ | |
985 | ||
986 | D1(printk("Dirty space: Starting 0x%x for 0x%x bytes\n", | |
987 | (unsigned int) start, (unsigned int) (pos - start))); | |
988 | jffs_fmalloced(fmc, (__u32) start, | |
989 | (__u32) (pos - start), NULL); | |
990 | }else{ | |
991 | /* "Flipping bits" detected. This means that our scan for them | |
992 | did not catch this offset. See check_partly_erased_sectors() for | |
993 | more info. | |
994 | */ | |
995 | ||
996 | D1(printk("jffs_scan_flash():wants to allocate dirty flash " | |
997 | "space for 0 bytes.\n")); | |
998 | D1(printk("jffs_scan_flash(): Flipping bits! We will free " | |
999 | "all allocated memory, erase this sector and remount\n")); | |
1000 | ||
1001 | /* calculate start of present sector */ | |
1002 | offset = (((__u32)pos)/(__u32)fmc->sector_size) * (__u32)fmc->sector_size; | |
1003 | ||
1004 | D1(printk("jffs_scan_flash():erasing sector starting 0x%x.\n", | |
1005 | offset)); | |
1006 | ||
1007 | if (flash_erase_region(fmc->mtd, | |
1008 | offset, fmc->sector_size) < 0) { | |
1009 | printk(KERN_ERR "JFFS: Erase of flash failed. " | |
1010 | "offset = %u, erase_size = %d\n", | |
1011 | offset , fmc->sector_size); | |
1012 | ||
1013 | flash_safe_release(fmc->mtd); | |
f99d49ad | 1014 | kfree(read_buf); |
1da177e4 LT |
1015 | return -1; /* bad, bad, bad! */ |
1016 | ||
1017 | } | |
1018 | flash_safe_release(fmc->mtd); | |
f99d49ad | 1019 | kfree(read_buf); |
1da177e4 LT |
1020 | |
1021 | return -EAGAIN; /* erased offending sector. Try mount one more time please. */ | |
1022 | } | |
1023 | }else{ | |
1024 | /* Being in here means that we have found free space that ends on an erase sector | |
1025 | boundary. | |
1026 | Count it in if we are still under NUMFREEALLOWED *and* it is at least 1 erase | |
1027 | sector in length. This will keep us from picking any little ole' space as "free". | |
1028 | */ | |
1029 | if((num_free_space < NUMFREEALLOWED) && | |
1030 | ((unsigned int)(pos - start) >= fmc->sector_size)){ | |
1031 | /* We really don't do anything to mark space as free, except *not* | |
1032 | mark it dirty and just advance the "pos" location pointer. | |
1033 | It will automatically be picked up as free space. | |
1034 | */ | |
1035 | num_free_space++; | |
1036 | D1(printk("Free space accepted: Starting 0x%x for 0x%x bytes\n", | |
1037 | (unsigned int) start, (unsigned int) (pos - start))); | |
1038 | }else{ | |
1039 | num_free_spc_not_accp++; | |
1040 | D1(printk("Free space (#%i) found but *Not* accepted: Starting " | |
1041 | "0x%x for 0x%x bytes\n", num_free_spc_not_accp, | |
1042 | (unsigned int) start, | |
1043 | (unsigned int) (pos - start))); | |
1044 | ||
1045 | /* Mark this space as dirty. We already have our free space. */ | |
1046 | D1(printk("Dirty space: Starting 0x%x for 0x%x bytes\n", | |
1047 | (unsigned int) start, (unsigned int) (pos - start))); | |
1048 | jffs_fmalloced(fmc, (__u32) start, | |
1049 | (__u32) (pos - start), NULL); | |
1050 | } | |
1051 | ||
1052 | } | |
1053 | if(num_free_space > NUMFREEALLOWED){ | |
1054 | printk(KERN_WARNING "jffs_scan_flash(): Found free space " | |
1055 | "number %i. Only %i free space is allowed.\n", | |
1056 | num_free_space, NUMFREEALLOWED); | |
1057 | } | |
1058 | continue; | |
1059 | ||
1060 | case JFFS_DIRTY_BITMASK: | |
1061 | /* We have found 0x00000000 at this position. Scan as far | |
1062 | as possible to find out how much is dirty. */ | |
1063 | D1(printk("jffs_scan_flash(): 0x00000000 at pos 0x%lx.\n", | |
1064 | (long)pos)); | |
1065 | for (; pos < end | |
1066 | && JFFS_DIRTY_BITMASK == flash_read_u32(fmc->mtd, pos); | |
1067 | pos += 4); | |
1068 | D1(printk("jffs_scan_flash(): 0x00 ended at " | |
1069 | "pos 0x%lx.\n", (long)pos)); | |
1070 | jffs_fmalloced(fmc, (__u32) start, | |
1071 | (__u32) (pos - start), NULL); | |
1072 | continue; | |
1073 | ||
1074 | case JFFS_MAGIC_BITMASK: | |
1075 | /* We have probably found a new raw inode. */ | |
1076 | break; | |
1077 | ||
1078 | default: | |
1079 | bad_inode: | |
1080 | /* We're f*cked. This is not solved yet. We have | |
1081 | to scan for the magic pattern. */ | |
1082 | D1(printk("*************** Dirty flash memory or " | |
1083 | "bad inode: " | |
1084 | "hexdump(pos = 0x%lx, len = 128):\n", | |
1085 | (long)pos)); | |
1086 | D1(jffs_hexdump(fmc->mtd, pos, 128)); | |
1087 | ||
1088 | for (pos += 4; pos < end; pos += 4) { | |
1089 | switch (flash_read_u32(fmc->mtd, pos)) { | |
1090 | case JFFS_MAGIC_BITMASK: | |
1091 | case JFFS_EMPTY_BITMASK: | |
1092 | /* handle these in the main switch() loop */ | |
1093 | goto cont_scan; | |
1094 | ||
1095 | default: | |
1096 | break; | |
1097 | } | |
1098 | } | |
1099 | ||
1100 | cont_scan: | |
1101 | /* First, mark as dirty the region | |
1102 | which really does contain crap. */ | |
1103 | jffs_fmalloced(fmc, (__u32) start, | |
1104 | (__u32) (pos - start), | |
1105 | NULL); | |
1106 | ||
1107 | continue; | |
1108 | }/* switch */ | |
1109 | ||
1110 | /* We have found the beginning of an inode. Create a | |
1111 | node for it unless there already is one available. */ | |
1112 | if (!node) { | |
1113 | if (!(node = jffs_alloc_node())) { | |
1114 | /* Free read buffer */ | |
f99d49ad | 1115 | kfree(read_buf); |
1da177e4 LT |
1116 | |
1117 | /* Release the flash device */ | |
1118 | flash_safe_release(fmc->mtd); | |
1119 | ||
1120 | return -ENOMEM; | |
1121 | } | |
1122 | DJM(no_jffs_node++); | |
1123 | } | |
1124 | ||
1125 | /* Read the next raw inode. */ | |
1126 | ||
1127 | flash_safe_read(fmc->mtd, pos, (u_char *) &raw_inode, | |
1128 | sizeof(struct jffs_raw_inode)); | |
1129 | ||
1130 | /* When we compute the checksum for the inode, we never | |
1131 | count the 'accurate' or the 'checksum' fields. */ | |
1132 | tmp_accurate = raw_inode.accurate; | |
1133 | tmp_chksum = raw_inode.chksum; | |
1134 | raw_inode.accurate = 0; | |
1135 | raw_inode.chksum = 0; | |
1136 | checksum = jffs_checksum(&raw_inode, | |
1137 | sizeof(struct jffs_raw_inode)); | |
1138 | raw_inode.accurate = tmp_accurate; | |
1139 | raw_inode.chksum = tmp_chksum; | |
1140 | ||
1141 | D3(printk("*** We have found this raw inode at pos 0x%lx " | |
1142 | "on the flash:\n", (long)pos)); | |
1143 | D3(jffs_print_raw_inode(&raw_inode)); | |
1144 | ||
1145 | if (checksum != raw_inode.chksum) { | |
1146 | D1(printk("jffs_scan_flash(): Bad checksum: " | |
1147 | "checksum = %u, " | |
1148 | "raw_inode.chksum = %u\n", | |
1149 | checksum, raw_inode.chksum)); | |
1150 | pos += sizeof(struct jffs_raw_inode); | |
1151 | jffs_fmalloced(fmc, (__u32) start, | |
1152 | (__u32) (pos - start), NULL); | |
1153 | /* Reuse this unused struct jffs_node. */ | |
1154 | continue; | |
1155 | } | |
1156 | ||
1157 | /* Check the raw inode read so far. Start with the | |
1158 | maximum length of the filename. */ | |
1159 | if (raw_inode.nsize > JFFS_MAX_NAME_LEN) { | |
1160 | printk(KERN_WARNING "jffs_scan_flash: Found a " | |
1161 | "JFFS node with name too large\n"); | |
1162 | goto bad_inode; | |
1163 | } | |
1164 | ||
1165 | if (raw_inode.rename && raw_inode.dsize != sizeof(__u32)) { | |
1166 | printk(KERN_WARNING "jffs_scan_flash: Found a " | |
1167 | "rename node with dsize %u.\n", | |
1168 | raw_inode.dsize); | |
1169 | jffs_print_raw_inode(&raw_inode); | |
1170 | goto bad_inode; | |
1171 | } | |
1172 | ||
1173 | /* The node's data segment should not exceed a | |
1174 | certain length. */ | |
1175 | if (raw_inode.dsize > fmc->max_chunk_size) { | |
1176 | printk(KERN_WARNING "jffs_scan_flash: Found a " | |
1177 | "JFFS node with dsize (0x%x) > max_chunk_size (0x%x)\n", | |
1178 | raw_inode.dsize, fmc->max_chunk_size); | |
1179 | goto bad_inode; | |
1180 | } | |
1181 | ||
1182 | pos += sizeof(struct jffs_raw_inode); | |
1183 | ||
1184 | /* This shouldn't be necessary because a node that | |
1185 | violates the flash boundaries shouldn't be written | |
1186 | in the first place. */ | |
1187 | if (pos >= end) { | |
1188 | goto check_node; | |
1189 | } | |
1190 | ||
1191 | /* Read the name. */ | |
1192 | *name = 0; | |
1193 | if (raw_inode.nsize) { | |
1194 | flash_safe_read(fmc->mtd, pos, name, raw_inode.nsize); | |
1195 | name[raw_inode.nsize] = '\0'; | |
1196 | pos += raw_inode.nsize | |
1197 | + JFFS_GET_PAD_BYTES(raw_inode.nsize); | |
1198 | D3(printk("name == \"%s\"\n", name)); | |
1199 | checksum = jffs_checksum(name, raw_inode.nsize); | |
1200 | if (checksum != raw_inode.nchksum) { | |
1201 | D1(printk("jffs_scan_flash(): Bad checksum: " | |
1202 | "checksum = %u, " | |
1203 | "raw_inode.nchksum = %u\n", | |
1204 | checksum, raw_inode.nchksum)); | |
1205 | jffs_fmalloced(fmc, (__u32) start, | |
1206 | (__u32) (pos - start), NULL); | |
1207 | /* Reuse this unused struct jffs_node. */ | |
1208 | continue; | |
1209 | } | |
1210 | if (pos >= end) { | |
1211 | goto check_node; | |
1212 | } | |
1213 | } | |
1214 | ||
1215 | /* Read the data, if it exists, in order to be sure it | |
1216 | matches the checksum. */ | |
1217 | if (raw_inode.dsize) { | |
1218 | if (raw_inode.rename) { | |
1219 | deleted_file = flash_read_u32(fmc->mtd, pos); | |
1220 | } | |
1221 | if (jffs_checksum_flash(fmc->mtd, pos, raw_inode.dsize, &checksum)) { | |
1222 | printk("jffs_checksum_flash() failed to calculate a checksum\n"); | |
1223 | jffs_fmalloced(fmc, (__u32) start, | |
1224 | (__u32) (pos - start), NULL); | |
1225 | /* Reuse this unused struct jffs_node. */ | |
1226 | continue; | |
1227 | } | |
1228 | pos += raw_inode.dsize | |
1229 | + JFFS_GET_PAD_BYTES(raw_inode.dsize); | |
1230 | ||
1231 | if (checksum != raw_inode.dchksum) { | |
1232 | D1(printk("jffs_scan_flash(): Bad checksum: " | |
1233 | "checksum = %u, " | |
1234 | "raw_inode.dchksum = %u\n", | |
1235 | checksum, raw_inode.dchksum)); | |
1236 | jffs_fmalloced(fmc, (__u32) start, | |
1237 | (__u32) (pos - start), NULL); | |
1238 | /* Reuse this unused struct jffs_node. */ | |
1239 | continue; | |
1240 | } | |
1241 | } | |
1242 | ||
1243 | check_node: | |
1244 | ||
1245 | /* Remember the highest inode number in the whole file | |
1246 | system. This information will be used when assigning | |
1247 | new files new inode numbers. */ | |
1248 | if (c->next_ino <= raw_inode.ino) { | |
1249 | c->next_ino = raw_inode.ino + 1; | |
1250 | } | |
1251 | ||
1252 | if (raw_inode.accurate) { | |
1253 | int err; | |
1254 | node->data_offset = raw_inode.offset; | |
1255 | node->data_size = raw_inode.dsize; | |
1256 | node->removed_size = raw_inode.rsize; | |
1257 | /* Compute the offset to the actual data in the | |
1258 | on-flash node. */ | |
1259 | node->fm_offset | |
1260 | = sizeof(struct jffs_raw_inode) | |
1261 | + raw_inode.nsize | |
1262 | + JFFS_GET_PAD_BYTES(raw_inode.nsize); | |
1263 | node->fm = jffs_fmalloced(fmc, (__u32) start, | |
1264 | (__u32) (pos - start), | |
1265 | node); | |
1266 | if (!node->fm) { | |
1267 | D(printk("jffs_scan_flash(): !node->fm\n")); | |
1268 | jffs_free_node(node); | |
1269 | DJM(no_jffs_node--); | |
1270 | ||
1271 | /* Free read buffer */ | |
f99d49ad | 1272 | kfree(read_buf); |
1da177e4 LT |
1273 | |
1274 | /* Release the flash device */ | |
1275 | flash_safe_release(fmc->mtd); | |
1276 | ||
1277 | return -ENOMEM; | |
1278 | } | |
1279 | if ((err = jffs_insert_node(c, NULL, &raw_inode, | |
1280 | name, node)) < 0) { | |
1281 | printk("JFFS: Failed to handle raw inode. " | |
1282 | "(err = %d)\n", err); | |
1283 | break; | |
1284 | } | |
1285 | if (raw_inode.rename) { | |
1286 | struct jffs_delete_list *dl | |
1287 | = (struct jffs_delete_list *) | |
1288 | kmalloc(sizeof(struct jffs_delete_list), | |
1289 | GFP_KERNEL); | |
1290 | if (!dl) { | |
1291 | D(printk("jffs_scan_flash: !dl\n")); | |
1292 | jffs_free_node(node); | |
1293 | DJM(no_jffs_node--); | |
1294 | ||
1295 | /* Release the flash device */ | |
1296 | flash_safe_release(fmc->flash_part); | |
1297 | ||
1298 | /* Free read buffer */ | |
f99d49ad | 1299 | kfree(read_buf); |
1da177e4 LT |
1300 | |
1301 | return -ENOMEM; | |
1302 | } | |
1303 | dl->ino = deleted_file; | |
1304 | dl->next = c->delete_list; | |
1305 | c->delete_list = dl; | |
1306 | node->data_size = 0; | |
1307 | } | |
1308 | D3(jffs_print_node(node)); | |
1309 | node = NULL; /* Don't free the node! */ | |
1310 | } | |
1311 | else { | |
1312 | jffs_fmalloced(fmc, (__u32) start, | |
1313 | (__u32) (pos - start), NULL); | |
1314 | D3(printk("jffs_scan_flash(): Just found an obsolete " | |
1315 | "raw_inode. Continuing the scan...\n")); | |
1316 | /* Reuse this unused struct jffs_node. */ | |
1317 | } | |
1318 | } | |
1319 | ||
1320 | if (node) { | |
1321 | jffs_free_node(node); | |
1322 | DJM(no_jffs_node--); | |
1323 | } | |
1324 | jffs_build_end(fmc); | |
1325 | ||
1326 | /* Free read buffer */ | |
f99d49ad | 1327 | kfree(read_buf); |
1da177e4 LT |
1328 | |
1329 | if(!num_free_space){ | |
1330 | printk(KERN_WARNING "jffs_scan_flash(): Did not find even a single " | |
1331 | "chunk of free space. This is BAD!\n"); | |
1332 | } | |
1333 | ||
1334 | /* Return happy */ | |
1335 | D3(printk("jffs_scan_flash(): Leaving...\n")); | |
1336 | flash_safe_release(fmc->mtd); | |
1337 | ||
1338 | /* This is to trap the "free size accounting screwed error. */ | |
1339 | free_chunk_size1 = jffs_free_size1(fmc); | |
1340 | free_chunk_size2 = jffs_free_size2(fmc); | |
1341 | ||
1342 | if (free_chunk_size1 + free_chunk_size2 != fmc->free_size) { | |
1343 | ||
1344 | printk(KERN_WARNING "jffs_scan_falsh():Free size accounting screwed\n"); | |
1345 | printk(KERN_WARNING "jfffs_scan_flash():free_chunk_size1 == 0x%x, " | |
1346 | "free_chunk_size2 == 0x%x, fmc->free_size == 0x%x\n", | |
1347 | free_chunk_size1, free_chunk_size2, fmc->free_size); | |
1348 | ||
1349 | return -1; /* Do NOT mount f/s so that we can inspect what happened. | |
1350 | Mounting this screwed up f/s will screw us up anyway. | |
1351 | */ | |
1352 | } | |
1353 | ||
1354 | return 0; /* as far as we are concerned, we are happy! */ | |
1355 | } /* jffs_scan_flash() */ | |
1356 | ||
1357 | ||
1358 | /* Insert any kind of node into the file system. Take care of data | |
1359 | insertions and deletions. Also remove redundant information. The | |
1360 | memory allocated for the `name' is regarded as "given away" in the | |
1361 | caller's perspective. */ | |
1362 | int | |
1363 | jffs_insert_node(struct jffs_control *c, struct jffs_file *f, | |
1364 | const struct jffs_raw_inode *raw_inode, | |
1365 | const char *name, struct jffs_node *node) | |
1366 | { | |
1367 | int update_name = 0; | |
1368 | int insert_into_tree = 0; | |
1369 | ||
1370 | D2(printk("jffs_insert_node(): ino = %u, version = %u, " | |
1371 | "name = \"%s\", deleted = %d\n", | |
1372 | raw_inode->ino, raw_inode->version, | |
1373 | ((name && *name) ? name : ""), raw_inode->deleted)); | |
1374 | ||
1375 | /* If there doesn't exist an associated jffs_file, then | |
1376 | create, initialize and insert one into the file system. */ | |
1377 | if (!f && !(f = jffs_find_file(c, raw_inode->ino))) { | |
1378 | if (!(f = jffs_create_file(c, raw_inode))) { | |
1379 | return -ENOMEM; | |
1380 | } | |
1381 | jffs_insert_file_into_hash(f); | |
1382 | insert_into_tree = 1; | |
1383 | } | |
1384 | node->ino = raw_inode->ino; | |
1385 | node->version = raw_inode->version; | |
1386 | node->data_size = raw_inode->dsize; | |
1387 | node->fm_offset = sizeof(struct jffs_raw_inode) + raw_inode->nsize | |
1388 | + JFFS_GET_PAD_BYTES(raw_inode->nsize); | |
1389 | node->name_size = raw_inode->nsize; | |
1390 | ||
1391 | /* Now insert the node at the correct position into the file's | |
1392 | version list. */ | |
1393 | if (!f->version_head) { | |
1394 | /* This is the first node. */ | |
1395 | f->version_head = node; | |
1396 | f->version_tail = node; | |
1397 | node->version_prev = NULL; | |
1398 | node->version_next = NULL; | |
1399 | f->highest_version = node->version; | |
1400 | update_name = 1; | |
1401 | f->mode = raw_inode->mode; | |
1402 | f->uid = raw_inode->uid; | |
1403 | f->gid = raw_inode->gid; | |
1404 | f->atime = raw_inode->atime; | |
1405 | f->mtime = raw_inode->mtime; | |
1406 | f->ctime = raw_inode->ctime; | |
1407 | } | |
1408 | else if ((f->highest_version < node->version) | |
1409 | || (node->version == 0)) { | |
1410 | /* Insert at the end of the list. I.e. this node is the | |
1411 | newest one so far. */ | |
1412 | node->version_prev = f->version_tail; | |
1413 | node->version_next = NULL; | |
1414 | f->version_tail->version_next = node; | |
1415 | f->version_tail = node; | |
1416 | f->highest_version = node->version; | |
1417 | update_name = 1; | |
1418 | f->pino = raw_inode->pino; | |
1419 | f->mode = raw_inode->mode; | |
1420 | f->uid = raw_inode->uid; | |
1421 | f->gid = raw_inode->gid; | |
1422 | f->atime = raw_inode->atime; | |
1423 | f->mtime = raw_inode->mtime; | |
1424 | f->ctime = raw_inode->ctime; | |
1425 | } | |
1426 | else if (f->version_head->version > node->version) { | |
1427 | /* Insert at the bottom of the list. */ | |
1428 | node->version_prev = NULL; | |
1429 | node->version_next = f->version_head; | |
1430 | f->version_head->version_prev = node; | |
1431 | f->version_head = node; | |
1432 | if (!f->name) { | |
1433 | update_name = 1; | |
1434 | } | |
1435 | } | |
1436 | else { | |
1437 | struct jffs_node *n; | |
1438 | int newer_name = 0; | |
1439 | /* Search for the insertion position starting from | |
1440 | the tail (newest node). */ | |
1441 | for (n = f->version_tail; n; n = n->version_prev) { | |
1442 | if (n->version < node->version) { | |
1443 | node->version_prev = n; | |
1444 | node->version_next = n->version_next; | |
1445 | node->version_next->version_prev = node; | |
1446 | n->version_next = node; | |
1447 | if (!newer_name) { | |
1448 | update_name = 1; | |
1449 | } | |
1450 | break; | |
1451 | } | |
1452 | if (n->name_size) { | |
1453 | newer_name = 1; | |
1454 | } | |
1455 | } | |
1456 | } | |
1457 | ||
1458 | /* Deletion is irreversible. If any 'deleted' node is ever | |
1459 | written, the file is deleted */ | |
1460 | if (raw_inode->deleted) | |
1461 | f->deleted = raw_inode->deleted; | |
1462 | ||
1463 | /* Perhaps update the name. */ | |
1464 | if (raw_inode->nsize && update_name && name && *name && (name != f->name)) { | |
1465 | if (f->name) { | |
1466 | kfree(f->name); | |
1467 | DJM(no_name--); | |
1468 | } | |
1469 | if (!(f->name = (char *) kmalloc(raw_inode->nsize + 1, | |
1470 | GFP_KERNEL))) { | |
1471 | return -ENOMEM; | |
1472 | } | |
1473 | DJM(no_name++); | |
1474 | memcpy(f->name, name, raw_inode->nsize); | |
1475 | f->name[raw_inode->nsize] = '\0'; | |
1476 | f->nsize = raw_inode->nsize; | |
1477 | D3(printk("jffs_insert_node(): Updated the name of " | |
1478 | "the file to \"%s\".\n", name)); | |
1479 | } | |
1480 | ||
1481 | if (!c->building_fs) { | |
1482 | D3(printk("jffs_insert_node(): ---------------------------" | |
1483 | "------------------------------------------- 1\n")); | |
1484 | if (insert_into_tree) { | |
1485 | jffs_insert_file_into_tree(f); | |
1486 | } | |
1487 | /* Once upon a time, we would call jffs_possibly_delete_file() | |
1488 | here. That causes an oops if someone's still got the file | |
1489 | open, so now we only do it in jffs_delete_inode() | |
1490 | -- dwmw2 | |
1491 | */ | |
1492 | if (node->data_size || node->removed_size) { | |
1493 | jffs_update_file(f, node); | |
1494 | } | |
1495 | jffs_remove_redundant_nodes(f); | |
1496 | ||
1497 | jffs_garbage_collect_trigger(c); | |
1498 | ||
1499 | D3(printk("jffs_insert_node(): ---------------------------" | |
1500 | "------------------------------------------- 2\n")); | |
1501 | } | |
1502 | ||
1503 | return 0; | |
1504 | } /* jffs_insert_node() */ | |
1505 | ||
1506 | ||
1507 | /* Unlink a jffs_node from the version list it is in. */ | |
1508 | static inline void | |
1509 | jffs_unlink_node_from_version_list(struct jffs_file *f, | |
1510 | struct jffs_node *node) | |
1511 | { | |
1512 | if (node->version_prev) { | |
1513 | node->version_prev->version_next = node->version_next; | |
1514 | } else { | |
1515 | f->version_head = node->version_next; | |
1516 | } | |
1517 | if (node->version_next) { | |
1518 | node->version_next->version_prev = node->version_prev; | |
1519 | } else { | |
1520 | f->version_tail = node->version_prev; | |
1521 | } | |
1522 | } | |
1523 | ||
1524 | ||
1525 | /* Unlink a jffs_node from the range list it is in. */ | |
1526 | static inline void | |
1527 | jffs_unlink_node_from_range_list(struct jffs_file *f, struct jffs_node *node) | |
1528 | { | |
1529 | if (node->range_prev) { | |
1530 | node->range_prev->range_next = node->range_next; | |
1531 | } | |
1532 | else { | |
1533 | f->range_head = node->range_next; | |
1534 | } | |
1535 | if (node->range_next) { | |
1536 | node->range_next->range_prev = node->range_prev; | |
1537 | } | |
1538 | else { | |
1539 | f->range_tail = node->range_prev; | |
1540 | } | |
1541 | } | |
1542 | ||
1543 | ||
1544 | /* Function used by jffs_remove_redundant_nodes() below. This function | |
1545 | classifies what kind of information a node adds to a file. */ | |
1546 | static inline __u8 | |
1547 | jffs_classify_node(struct jffs_node *node) | |
1548 | { | |
1549 | __u8 mod_type = JFFS_MODIFY_INODE; | |
1550 | ||
1551 | if (node->name_size) { | |
1552 | mod_type |= JFFS_MODIFY_NAME; | |
1553 | } | |
1554 | if (node->data_size || node->removed_size) { | |
1555 | mod_type |= JFFS_MODIFY_DATA; | |
1556 | } | |
1557 | return mod_type; | |
1558 | } | |
1559 | ||
1560 | ||
1561 | /* Remove redundant nodes from a file. Mark the on-flash memory | |
1562 | as dirty. */ | |
1563 | static int | |
1564 | jffs_remove_redundant_nodes(struct jffs_file *f) | |
1565 | { | |
1566 | struct jffs_node *newest_node; | |
1567 | struct jffs_node *cur; | |
1568 | struct jffs_node *prev; | |
1569 | __u8 newest_type; | |
1570 | __u8 mod_type; | |
1571 | __u8 node_with_name_later = 0; | |
1572 | ||
1573 | if (!(newest_node = f->version_tail)) { | |
1574 | return 0; | |
1575 | } | |
1576 | ||
1577 | /* What does the `newest_node' modify? */ | |
1578 | newest_type = jffs_classify_node(newest_node); | |
1579 | node_with_name_later = newest_type & JFFS_MODIFY_NAME; | |
1580 | ||
1581 | D3(printk("jffs_remove_redundant_nodes(): ino: %u, name: \"%s\", " | |
1582 | "newest_type: %u\n", f->ino, (f->name ? f->name : ""), | |
1583 | newest_type)); | |
1584 | ||
1585 | /* Traverse the file's nodes and determine which of them that are | |
1586 | superfluous. Yeah, this might look very complex at first | |
1587 | glance but it is actually very simple. */ | |
1588 | for (cur = newest_node->version_prev; cur; cur = prev) { | |
1589 | prev = cur->version_prev; | |
1590 | mod_type = jffs_classify_node(cur); | |
1591 | if ((mod_type <= JFFS_MODIFY_INODE) | |
1592 | || ((newest_type & JFFS_MODIFY_NAME) | |
1593 | && (mod_type | |
1594 | <= (JFFS_MODIFY_INODE + JFFS_MODIFY_NAME))) | |
1595 | || (cur->data_size == 0 && cur->removed_size | |
1596 | && !cur->version_prev && node_with_name_later)) { | |
1597 | /* Yes, this node is redundant. Remove it. */ | |
1598 | D2(printk("jffs_remove_redundant_nodes(): " | |
1599 | "Removing node: ino: %u, version: %u, " | |
1600 | "mod_type: %u\n", cur->ino, cur->version, | |
1601 | mod_type)); | |
1602 | jffs_unlink_node_from_version_list(f, cur); | |
1603 | jffs_fmfree(f->c->fmc, cur->fm, cur); | |
1604 | jffs_free_node(cur); | |
1605 | DJM(no_jffs_node--); | |
1606 | } | |
1607 | else { | |
1608 | node_with_name_later |= (mod_type & JFFS_MODIFY_NAME); | |
1609 | } | |
1610 | } | |
1611 | ||
1612 | return 0; | |
1613 | } | |
1614 | ||
1615 | ||
1616 | /* Insert a file into the hash table. */ | |
1617 | static int | |
1618 | jffs_insert_file_into_hash(struct jffs_file *f) | |
1619 | { | |
1620 | int i = f->ino % f->c->hash_len; | |
1621 | ||
1622 | D3(printk("jffs_insert_file_into_hash(): f->ino: %u\n", f->ino)); | |
1623 | ||
1624 | list_add(&f->hash, &f->c->hash[i]); | |
1625 | return 0; | |
1626 | } | |
1627 | ||
1628 | ||
1629 | /* Insert a file into the file system tree. */ | |
1630 | int | |
1631 | jffs_insert_file_into_tree(struct jffs_file *f) | |
1632 | { | |
1633 | struct jffs_file *parent; | |
1634 | ||
1635 | D3(printk("jffs_insert_file_into_tree(): name: \"%s\"\n", | |
1636 | (f->name ? f->name : ""))); | |
1637 | ||
1638 | if (!(parent = jffs_find_file(f->c, f->pino))) { | |
1639 | if (f->pino == 0) { | |
1640 | f->c->root = f; | |
1641 | f->parent = NULL; | |
1642 | f->sibling_prev = NULL; | |
1643 | f->sibling_next = NULL; | |
1644 | return 0; | |
1645 | } | |
1646 | else { | |
1647 | D1(printk("jffs_insert_file_into_tree(): Found " | |
1648 | "inode with no parent and pino == %u\n", | |
1649 | f->pino)); | |
1650 | return -1; | |
1651 | } | |
1652 | } | |
1653 | f->parent = parent; | |
1654 | f->sibling_next = parent->children; | |
1655 | if (f->sibling_next) { | |
1656 | f->sibling_next->sibling_prev = f; | |
1657 | } | |
1658 | f->sibling_prev = NULL; | |
1659 | parent->children = f; | |
1660 | return 0; | |
1661 | } | |
1662 | ||
1663 | ||
1664 | /* Remove a file from the hash table. */ | |
1665 | static int | |
1666 | jffs_unlink_file_from_hash(struct jffs_file *f) | |
1667 | { | |
1668 | D3(printk("jffs_unlink_file_from_hash(): f: 0x%p, " | |
1669 | "ino %u\n", f, f->ino)); | |
1670 | ||
1671 | list_del(&f->hash); | |
1672 | return 0; | |
1673 | } | |
1674 | ||
1675 | ||
1676 | /* Just remove the file from the parent's children. Don't free | |
1677 | any memory. */ | |
1678 | int | |
1679 | jffs_unlink_file_from_tree(struct jffs_file *f) | |
1680 | { | |
1681 | D3(printk("jffs_unlink_file_from_tree(): ino: %d, pino: %d, name: " | |
1682 | "\"%s\"\n", f->ino, f->pino, (f->name ? f->name : ""))); | |
1683 | ||
1684 | if (f->sibling_prev) { | |
1685 | f->sibling_prev->sibling_next = f->sibling_next; | |
1686 | } | |
1687 | else if (f->parent) { | |
1688 | D3(printk("f->parent=%p\n", f->parent)); | |
1689 | f->parent->children = f->sibling_next; | |
1690 | } | |
1691 | if (f->sibling_next) { | |
1692 | f->sibling_next->sibling_prev = f->sibling_prev; | |
1693 | } | |
1694 | return 0; | |
1695 | } | |
1696 | ||
1697 | ||
1698 | /* Find a file with its inode number. */ | |
1699 | struct jffs_file * | |
1700 | jffs_find_file(struct jffs_control *c, __u32 ino) | |
1701 | { | |
1702 | struct jffs_file *f; | |
1703 | int i = ino % c->hash_len; | |
1da177e4 LT |
1704 | |
1705 | D3(printk("jffs_find_file(): ino: %u\n", ino)); | |
1706 | ||
216d81bb | 1707 | list_for_each_entry(f, &c->hash[i], hash) { |
1da177e4 LT |
1708 | if (ino != f->ino) |
1709 | continue; | |
1710 | D3(printk("jffs_find_file(): Found file with ino " | |
1711 | "%u. (name: \"%s\")\n", | |
1712 | ino, (f->name ? f->name : "")); | |
1713 | ); | |
1714 | return f; | |
1715 | } | |
1716 | D3(printk("jffs_find_file(): Didn't find file " | |
1717 | "with ino %u.\n", ino); | |
1718 | ); | |
1719 | return NULL; | |
1720 | } | |
1721 | ||
1722 | ||
1723 | /* Find a file in a directory. We are comparing the names. */ | |
1724 | struct jffs_file * | |
1725 | jffs_find_child(struct jffs_file *dir, const char *name, int len) | |
1726 | { | |
1727 | struct jffs_file *f; | |
1728 | ||
1729 | D3(printk("jffs_find_child()\n")); | |
1730 | ||
1731 | for (f = dir->children; f; f = f->sibling_next) { | |
1732 | if (!f->deleted && f->name | |
1733 | && !strncmp(f->name, name, len) | |
1734 | && f->name[len] == '\0') { | |
1735 | break; | |
1736 | } | |
1737 | } | |
1738 | ||
1739 | D3(if (f) { | |
1740 | printk("jffs_find_child(): Found \"%s\".\n", f->name); | |
1741 | } | |
1742 | else { | |
1743 | char *copy = (char *) kmalloc(len + 1, GFP_KERNEL); | |
1744 | if (copy) { | |
1745 | memcpy(copy, name, len); | |
1746 | copy[len] = '\0'; | |
1747 | } | |
1748 | printk("jffs_find_child(): Didn't find the file \"%s\".\n", | |
1749 | (copy ? copy : "")); | |
f99d49ad | 1750 | kfree(copy); |
1da177e4 LT |
1751 | }); |
1752 | ||
1753 | return f; | |
1754 | } | |
1755 | ||
1756 | ||
1757 | /* Write a raw inode that takes up a certain amount of space in the flash | |
1758 | memory. At the end of the flash device, there is often space that is | |
1759 | impossible to use. At these times we want to mark this space as not | |
1760 | used. In the cases when the amount of space is greater or equal than | |
1761 | a struct jffs_raw_inode, we write a "dummy node" that takes up this | |
1762 | space. The space after the raw inode, if it exists, is left as it is. | |
1763 | Since this space after the raw inode contains JFFS_EMPTY_BITMASK bytes, | |
1764 | we can compute the checksum of it; we don't have to manipulate it any | |
1765 | further. | |
1766 | ||
1767 | If the space left on the device is less than the size of a struct | |
1768 | jffs_raw_inode, this space is filled with JFFS_DIRTY_BITMASK bytes. | |
1769 | No raw inode is written this time. */ | |
1770 | static int | |
1771 | jffs_write_dummy_node(struct jffs_control *c, struct jffs_fm *dirty_fm) | |
1772 | { | |
1773 | struct jffs_fmcontrol *fmc = c->fmc; | |
1774 | int err; | |
1775 | ||
1776 | D1(printk("jffs_write_dummy_node(): dirty_fm->offset = 0x%08x, " | |
1777 | "dirty_fm->size = %u\n", | |
1778 | dirty_fm->offset, dirty_fm->size)); | |
1779 | ||
1780 | if (dirty_fm->size >= sizeof(struct jffs_raw_inode)) { | |
1781 | struct jffs_raw_inode raw_inode; | |
1782 | memset(&raw_inode, 0, sizeof(struct jffs_raw_inode)); | |
1783 | raw_inode.magic = JFFS_MAGIC_BITMASK; | |
1784 | raw_inode.dsize = dirty_fm->size | |
1785 | - sizeof(struct jffs_raw_inode); | |
1786 | raw_inode.dchksum = raw_inode.dsize * 0xff; | |
1787 | raw_inode.chksum | |
1788 | = jffs_checksum(&raw_inode, sizeof(struct jffs_raw_inode)); | |
1789 | ||
1790 | if ((err = flash_safe_write(fmc->mtd, | |
1791 | dirty_fm->offset, | |
1792 | (u_char *)&raw_inode, | |
1793 | sizeof(struct jffs_raw_inode))) | |
1794 | < 0) { | |
1795 | printk(KERN_ERR "JFFS: jffs_write_dummy_node: " | |
1796 | "flash_safe_write failed!\n"); | |
1797 | return err; | |
1798 | } | |
1799 | } | |
1800 | else { | |
1801 | flash_safe_acquire(fmc->mtd); | |
1802 | flash_memset(fmc->mtd, dirty_fm->offset, 0, dirty_fm->size); | |
1803 | flash_safe_release(fmc->mtd); | |
1804 | } | |
1805 | ||
1806 | D3(printk("jffs_write_dummy_node(): Leaving...\n")); | |
1807 | return 0; | |
1808 | } | |
1809 | ||
1810 | ||
1811 | /* Write a raw inode, possibly its name and possibly some data. */ | |
1812 | int | |
1813 | jffs_write_node(struct jffs_control *c, struct jffs_node *node, | |
1814 | struct jffs_raw_inode *raw_inode, | |
1815 | const char *name, const unsigned char *data, | |
1816 | int recoverable, | |
1817 | struct jffs_file *f) | |
1818 | { | |
1819 | struct jffs_fmcontrol *fmc = c->fmc; | |
1820 | struct jffs_fm *fm; | |
1821 | struct kvec node_iovec[4]; | |
1822 | unsigned long iovec_cnt; | |
1823 | ||
1824 | __u32 pos; | |
1825 | int err; | |
1826 | __u32 slack = 0; | |
1827 | ||
1828 | __u32 total_name_size = raw_inode->nsize | |
1829 | + JFFS_GET_PAD_BYTES(raw_inode->nsize); | |
1830 | __u32 total_data_size = raw_inode->dsize | |
1831 | + JFFS_GET_PAD_BYTES(raw_inode->dsize); | |
1832 | __u32 total_size = sizeof(struct jffs_raw_inode) | |
1833 | + total_name_size + total_data_size; | |
1834 | ||
1835 | /* If this node isn't something that will eventually let | |
1836 | GC free even more space, then don't allow it unless | |
1837 | there's at least max_chunk_size space still available | |
1838 | */ | |
1839 | if (!recoverable) | |
1840 | slack = fmc->max_chunk_size; | |
1841 | ||
1842 | ||
1843 | /* Fire the retrorockets and shoot the fruiton torpedoes, sir! */ | |
1844 | ||
1845 | ASSERT(if (!node) { | |
1846 | printk("jffs_write_node(): node == NULL\n"); | |
1847 | return -EINVAL; | |
1848 | }); | |
1849 | ASSERT(if (raw_inode && raw_inode->nsize && !name) { | |
1850 | printk("*** jffs_write_node(): nsize = %u but name == NULL\n", | |
1851 | raw_inode->nsize); | |
1852 | return -EINVAL; | |
1853 | }); | |
1854 | ||
1855 | D1(printk("jffs_write_node(): filename = \"%s\", ino = %u, " | |
1856 | "total_size = %u\n", | |
1857 | (name ? name : ""), raw_inode->ino, | |
1858 | total_size)); | |
1859 | ||
1860 | jffs_fm_write_lock(fmc); | |
1861 | ||
1862 | retry: | |
1863 | fm = NULL; | |
1864 | err = 0; | |
1865 | while (!fm) { | |
1866 | ||
1867 | /* Deadlocks suck. */ | |
1868 | while(fmc->free_size < fmc->min_free_size + total_size + slack) { | |
1869 | jffs_fm_write_unlock(fmc); | |
1870 | if (!JFFS_ENOUGH_SPACE(c, total_size + slack)) | |
1871 | return -ENOSPC; | |
1872 | jffs_fm_write_lock(fmc); | |
1873 | } | |
1874 | ||
1875 | /* First try to allocate some flash memory. */ | |
1876 | err = jffs_fmalloc(fmc, total_size, node, &fm); | |
1877 | ||
1878 | if (err == -ENOSPC) { | |
1879 | /* Just out of space. GC and try again */ | |
1880 | if (fmc->dirty_size < fmc->sector_size) { | |
1881 | D(printk("jffs_write_node(): jffs_fmalloc(0x%p, %u) " | |
1882 | "failed, no dirty space to GC\n", fmc, | |
1883 | total_size)); | |
1884 | return err; | |
1885 | } | |
1886 | ||
1887 | D1(printk(KERN_INFO "jffs_write_node(): Calling jffs_garbage_collect_now()\n")); | |
1888 | jffs_fm_write_unlock(fmc); | |
1889 | if ((err = jffs_garbage_collect_now(c))) { | |
1890 | D(printk("jffs_write_node(): jffs_garbage_collect_now() failed\n")); | |
1891 | return err; | |
1892 | } | |
1893 | jffs_fm_write_lock(fmc); | |
1894 | continue; | |
1895 | } | |
1896 | ||
1897 | if (err < 0) { | |
1898 | jffs_fm_write_unlock(fmc); | |
1899 | ||
1900 | D(printk("jffs_write_node(): jffs_fmalloc(0x%p, %u) " | |
1901 | "failed!\n", fmc, total_size)); | |
1902 | return err; | |
1903 | } | |
1904 | ||
1905 | if (!fm->nodes) { | |
1906 | /* The jffs_fm struct that we got is not good enough. | |
1907 | Make that space dirty and try again */ | |
1908 | if ((err = jffs_write_dummy_node(c, fm)) < 0) { | |
1909 | kfree(fm); | |
1910 | DJM(no_jffs_fm--); | |
1911 | jffs_fm_write_unlock(fmc); | |
1912 | D(printk("jffs_write_node(): " | |
1913 | "jffs_write_dummy_node(): Failed!\n")); | |
1914 | return err; | |
1915 | } | |
1916 | fm = NULL; | |
1917 | } | |
1918 | } /* while(!fm) */ | |
1919 | node->fm = fm; | |
1920 | ||
1921 | ASSERT(if (fm->nodes == 0) { | |
1922 | printk(KERN_ERR "jffs_write_node(): fm->nodes == 0\n"); | |
1923 | }); | |
1924 | ||
1925 | pos = node->fm->offset; | |
1926 | ||
1927 | /* Increment the version number here. We can't let the caller | |
1928 | set it beforehand, because we might have had to do GC on a node | |
1929 | of this file - and we'd end up reusing version numbers. | |
1930 | */ | |
1931 | if (f) { | |
1932 | raw_inode->version = f->highest_version + 1; | |
1933 | D1(printk (KERN_NOTICE "jffs_write_node(): setting version of %s to %d\n", f->name, raw_inode->version)); | |
1934 | ||
1935 | /* if the file was deleted, set the deleted bit in the raw inode */ | |
1936 | if (f->deleted) | |
1937 | raw_inode->deleted = 1; | |
1938 | } | |
1939 | ||
1940 | /* Compute the checksum for the data and name chunks. */ | |
1941 | raw_inode->dchksum = jffs_checksum(data, raw_inode->dsize); | |
1942 | raw_inode->nchksum = jffs_checksum(name, raw_inode->nsize); | |
1943 | ||
1944 | /* The checksum is calculated without the chksum and accurate | |
1945 | fields so set them to zero first. */ | |
1946 | raw_inode->accurate = 0; | |
1947 | raw_inode->chksum = 0; | |
1948 | raw_inode->chksum = jffs_checksum(raw_inode, | |
1949 | sizeof(struct jffs_raw_inode)); | |
1950 | raw_inode->accurate = 0xff; | |
1951 | ||
1952 | D3(printk("jffs_write_node(): About to write this raw inode to the " | |
1953 | "flash at pos 0x%lx:\n", (long)pos)); | |
1954 | D3(jffs_print_raw_inode(raw_inode)); | |
1955 | ||
1956 | /* The actual raw JFFS node */ | |
1957 | node_iovec[0].iov_base = (void *) raw_inode; | |
1958 | node_iovec[0].iov_len = (size_t) sizeof(struct jffs_raw_inode); | |
1959 | iovec_cnt = 1; | |
1960 | ||
1961 | /* Get name and size if there is one */ | |
1962 | if (raw_inode->nsize) { | |
1963 | node_iovec[iovec_cnt].iov_base = (void *) name; | |
1964 | node_iovec[iovec_cnt].iov_len = (size_t) raw_inode->nsize; | |
1965 | iovec_cnt++; | |
1966 | ||
1967 | if (JFFS_GET_PAD_BYTES(raw_inode->nsize)) { | |
bd3bfeb5 | 1968 | static unsigned char allff[3]={255,255,255}; |
1da177e4 LT |
1969 | /* Add some extra padding if necessary */ |
1970 | node_iovec[iovec_cnt].iov_base = allff; | |
1971 | node_iovec[iovec_cnt].iov_len = | |
1972 | JFFS_GET_PAD_BYTES(raw_inode->nsize); | |
1973 | iovec_cnt++; | |
1974 | } | |
1975 | } | |
1976 | ||
1977 | /* Get data and size if there is any */ | |
1978 | if (raw_inode->dsize) { | |
1979 | node_iovec[iovec_cnt].iov_base = (void *) data; | |
1980 | node_iovec[iovec_cnt].iov_len = (size_t) raw_inode->dsize; | |
1981 | iovec_cnt++; | |
1982 | /* No need to pad this because we're not actually putting | |
1983 | anything after it. | |
1984 | */ | |
1985 | } | |
1986 | ||
1987 | if ((err = flash_safe_writev(fmc->mtd, node_iovec, iovec_cnt, | |
1988 | pos)) < 0) { | |
1989 | jffs_fmfree_partly(fmc, fm, 0); | |
1990 | jffs_fm_write_unlock(fmc); | |
1991 | printk(KERN_ERR "JFFS: jffs_write_node: Failed to write, " | |
1992 | "requested %i, wrote %i\n", total_size, err); | |
1993 | goto retry; | |
1994 | } | |
1995 | if (raw_inode->deleted) | |
1996 | f->deleted = 1; | |
1997 | ||
1998 | jffs_fm_write_unlock(fmc); | |
1999 | D3(printk("jffs_write_node(): Leaving...\n")); | |
2000 | return raw_inode->dsize; | |
2001 | } /* jffs_write_node() */ | |
2002 | ||
2003 | ||
2004 | /* Read data from the node and write it to the buffer. 'node_offset' | |
2005 | is how much we have read from this particular node before and which | |
2006 | shouldn't be read again. 'max_size' is how much space there is in | |
2007 | the buffer. */ | |
2008 | static int | |
2009 | jffs_get_node_data(struct jffs_file *f, struct jffs_node *node, | |
2010 | unsigned char *buf,__u32 node_offset, __u32 max_size) | |
2011 | { | |
2012 | struct jffs_fmcontrol *fmc = f->c->fmc; | |
2013 | __u32 pos = node->fm->offset + node->fm_offset + node_offset; | |
2014 | __u32 avail = node->data_size - node_offset; | |
2015 | __u32 r; | |
2016 | ||
2017 | D2(printk(" jffs_get_node_data(): file: \"%s\", ino: %u, " | |
2018 | "version: %u, node_offset: %u\n", | |
2019 | f->name, node->ino, node->version, node_offset)); | |
2020 | ||
2021 | r = min(avail, max_size); | |
2022 | D3(printk(KERN_NOTICE "jffs_get_node_data\n")); | |
2023 | flash_safe_read(fmc->mtd, pos, buf, r); | |
2024 | ||
2025 | D3(printk(" jffs_get_node_data(): Read %u byte%s.\n", | |
2026 | r, (r == 1 ? "" : "s"))); | |
2027 | ||
2028 | return r; | |
2029 | } | |
2030 | ||
2031 | ||
2032 | /* Read data from the file's nodes. Write the data to the buffer | |
2033 | 'buf'. 'read_offset' tells how much data we should skip. */ | |
2034 | int | |
2035 | jffs_read_data(struct jffs_file *f, unsigned char *buf, __u32 read_offset, | |
2036 | __u32 size) | |
2037 | { | |
2038 | struct jffs_node *node; | |
2039 | __u32 read_data = 0; /* Total amount of read data. */ | |
2040 | __u32 node_offset = 0; | |
2041 | __u32 pos = 0; /* Number of bytes traversed. */ | |
2042 | ||
2043 | D2(printk("jffs_read_data(): file = \"%s\", read_offset = %d, " | |
2044 | "size = %u\n", | |
2045 | (f->name ? f->name : ""), read_offset, size)); | |
2046 | ||
2047 | if (read_offset >= f->size) { | |
2048 | D(printk(" f->size: %d\n", f->size)); | |
2049 | return 0; | |
2050 | } | |
2051 | ||
2052 | /* First find the node to read data from. */ | |
2053 | node = f->range_head; | |
2054 | while (pos <= read_offset) { | |
2055 | node_offset = read_offset - pos; | |
2056 | if (node_offset >= node->data_size) { | |
2057 | pos += node->data_size; | |
2058 | node = node->range_next; | |
2059 | } | |
2060 | else { | |
2061 | break; | |
2062 | } | |
2063 | } | |
2064 | ||
2065 | /* "Cats are living proof that not everything in nature | |
2066 | has to be useful." | |
2067 | - Garrison Keilor ('97) */ | |
2068 | ||
2069 | /* Fill the buffer. */ | |
2070 | while (node && (read_data < size)) { | |
2071 | int r; | |
2072 | if (!node->fm) { | |
2073 | /* This node does not refer to real data. */ | |
2074 | r = min(size - read_data, | |
2075 | node->data_size - node_offset); | |
2076 | memset(&buf[read_data], 0, r); | |
2077 | } | |
2078 | else if ((r = jffs_get_node_data(f, node, &buf[read_data], | |
2079 | node_offset, | |
2080 | size - read_data)) < 0) { | |
2081 | return r; | |
2082 | } | |
2083 | read_data += r; | |
2084 | node_offset = 0; | |
2085 | node = node->range_next; | |
2086 | } | |
2087 | D3(printk(" jffs_read_data(): Read %u bytes.\n", read_data)); | |
2088 | return read_data; | |
2089 | } | |
2090 | ||
2091 | ||
2092 | /* Used for traversing all nodes in the hash table. */ | |
2093 | int | |
2094 | jffs_foreach_file(struct jffs_control *c, int (*func)(struct jffs_file *)) | |
2095 | { | |
2096 | int pos; | |
2097 | int r; | |
2098 | int result = 0; | |
2099 | ||
2100 | for (pos = 0; pos < c->hash_len; pos++) { | |
216d81bb DP |
2101 | struct jffs_file *f, *next; |
2102 | ||
2103 | /* We must do _safe, because 'func' might remove the | |
2104 | current file 'f' from the list. */ | |
2105 | list_for_each_entry_safe(f, next, &c->hash[pos], hash) { | |
2106 | r = func(f); | |
1da177e4 LT |
2107 | if (r < 0) |
2108 | return r; | |
2109 | result += r; | |
2110 | } | |
2111 | } | |
2112 | ||
2113 | return result; | |
2114 | } | |
2115 | ||
2116 | ||
2117 | /* Free all nodes associated with a file. */ | |
2118 | static int | |
2119 | jffs_free_node_list(struct jffs_file *f) | |
2120 | { | |
2121 | struct jffs_node *node; | |
2122 | struct jffs_node *p; | |
2123 | ||
2124 | D3(printk("jffs_free_node_list(): f #%u, \"%s\"\n", | |
2125 | f->ino, (f->name ? f->name : ""))); | |
2126 | node = f->version_head; | |
2127 | while (node) { | |
2128 | p = node; | |
2129 | node = node->version_next; | |
2130 | jffs_free_node(p); | |
2131 | DJM(no_jffs_node--); | |
2132 | } | |
2133 | return 0; | |
2134 | } | |
2135 | ||
2136 | ||
2137 | /* Free a file and its name. */ | |
2138 | static int | |
2139 | jffs_free_file(struct jffs_file *f) | |
2140 | { | |
2141 | D3(printk("jffs_free_file: f #%u, \"%s\"\n", | |
2142 | f->ino, (f->name ? f->name : ""))); | |
2143 | ||
2144 | if (f->name) { | |
2145 | kfree(f->name); | |
2146 | DJM(no_name--); | |
2147 | } | |
2148 | kfree(f); | |
2149 | no_jffs_file--; | |
2150 | return 0; | |
2151 | } | |
2152 | ||
2153 | static long | |
2154 | jffs_get_file_count(void) | |
2155 | { | |
2156 | return no_jffs_file; | |
2157 | } | |
2158 | ||
2159 | /* See if a file is deleted. If so, mark that file's nodes as obsolete. */ | |
2160 | int | |
2161 | jffs_possibly_delete_file(struct jffs_file *f) | |
2162 | { | |
2163 | struct jffs_node *n; | |
2164 | ||
2165 | D3(printk("jffs_possibly_delete_file(): ino: %u\n", | |
2166 | f->ino)); | |
2167 | ||
2168 | ASSERT(if (!f) { | |
2169 | printk(KERN_ERR "jffs_possibly_delete_file(): f == NULL\n"); | |
2170 | return -1; | |
2171 | }); | |
2172 | ||
2173 | if (f->deleted) { | |
2174 | /* First try to remove all older versions. Commence with | |
2175 | the oldest node. */ | |
2176 | for (n = f->version_head; n; n = n->version_next) { | |
2177 | if (!n->fm) { | |
2178 | continue; | |
2179 | } | |
2180 | if (jffs_fmfree(f->c->fmc, n->fm, n) < 0) { | |
2181 | break; | |
2182 | } | |
2183 | } | |
2184 | /* Unlink the file from the filesystem. */ | |
2185 | if (!f->c->building_fs) { | |
2186 | jffs_unlink_file_from_tree(f); | |
2187 | } | |
2188 | jffs_unlink_file_from_hash(f); | |
2189 | jffs_free_node_list(f); | |
2190 | jffs_free_file(f); | |
2191 | } | |
2192 | return 0; | |
2193 | } | |
2194 | ||
2195 | ||
2196 | /* Used in conjunction with jffs_foreach_file() to count the number | |
2197 | of files in the file system. */ | |
2198 | int | |
2199 | jffs_file_count(struct jffs_file *f) | |
2200 | { | |
2201 | return 1; | |
2202 | } | |
2203 | ||
2204 | ||
2205 | /* Build up a file's range list from scratch by going through the | |
2206 | version list. */ | |
2207 | static int | |
2208 | jffs_build_file(struct jffs_file *f) | |
2209 | { | |
2210 | struct jffs_node *n; | |
2211 | ||
2212 | D3(printk("jffs_build_file(): ino: %u, name: \"%s\"\n", | |
2213 | f->ino, (f->name ? f->name : ""))); | |
2214 | ||
2215 | for (n = f->version_head; n; n = n->version_next) { | |
2216 | jffs_update_file(f, n); | |
2217 | } | |
2218 | return 0; | |
2219 | } | |
2220 | ||
2221 | ||
2222 | /* Remove an amount of data from a file. If this amount of data is | |
2223 | zero, that could mean that a node should be split in two parts. | |
2224 | We remove or change the appropriate nodes in the lists. | |
2225 | ||
2226 | Starting offset of area to be removed is node->data_offset, | |
2227 | and the length of the area is in node->removed_size. */ | |
2228 | static int | |
2229 | jffs_delete_data(struct jffs_file *f, struct jffs_node *node) | |
2230 | { | |
2231 | struct jffs_node *n; | |
2232 | __u32 offset = node->data_offset; | |
2233 | __u32 remove_size = node->removed_size; | |
2234 | ||
2235 | D3(printk("jffs_delete_data(): offset = %u, remove_size = %u\n", | |
2236 | offset, remove_size)); | |
2237 | ||
2238 | if (remove_size == 0 | |
2239 | && f->range_tail | |
2240 | && f->range_tail->data_offset + f->range_tail->data_size | |
2241 | == offset) { | |
2242 | /* A simple append; nothing to remove or no node to split. */ | |
2243 | return 0; | |
2244 | } | |
2245 | ||
2246 | /* Find the node where we should begin the removal. */ | |
2247 | for (n = f->range_head; n; n = n->range_next) { | |
2248 | if (n->data_offset + n->data_size > offset) { | |
2249 | break; | |
2250 | } | |
2251 | } | |
2252 | if (!n) { | |
2253 | /* If there's no data in the file there's no data to | |
2254 | remove either. */ | |
2255 | return 0; | |
2256 | } | |
2257 | ||
2258 | if (n->data_offset > offset) { | |
2259 | /* XXX: Not implemented yet. */ | |
2260 | printk(KERN_WARNING "JFFS: An unexpected situation " | |
2261 | "occurred in jffs_delete_data.\n"); | |
2262 | } | |
2263 | else if (n->data_offset < offset) { | |
2264 | /* See if the node has to be split into two parts. */ | |
2265 | if (n->data_offset + n->data_size > offset + remove_size) { | |
2266 | /* Do the split. */ | |
2267 | struct jffs_node *new_node; | |
2268 | D3(printk("jffs_delete_data(): Split node with " | |
2269 | "version number %u.\n", n->version)); | |
2270 | ||
2271 | if (!(new_node = jffs_alloc_node())) { | |
2272 | D(printk("jffs_delete_data(): -ENOMEM\n")); | |
2273 | return -ENOMEM; | |
2274 | } | |
2275 | DJM(no_jffs_node++); | |
2276 | ||
2277 | new_node->ino = n->ino; | |
2278 | new_node->version = n->version; | |
2279 | new_node->data_offset = offset; | |
2280 | new_node->data_size = n->data_size - (remove_size + (offset - n->data_offset)); | |
2281 | new_node->fm_offset = n->fm_offset + (remove_size + (offset - n->data_offset)); | |
2282 | new_node->name_size = n->name_size; | |
2283 | new_node->fm = n->fm; | |
2284 | new_node->version_prev = n; | |
2285 | new_node->version_next = n->version_next; | |
2286 | if (new_node->version_next) { | |
2287 | new_node->version_next->version_prev | |
2288 | = new_node; | |
2289 | } | |
2290 | else { | |
2291 | f->version_tail = new_node; | |
2292 | } | |
2293 | n->version_next = new_node; | |
2294 | new_node->range_prev = n; | |
2295 | new_node->range_next = n->range_next; | |
2296 | if (new_node->range_next) { | |
2297 | new_node->range_next->range_prev = new_node; | |
2298 | } | |
2299 | else { | |
2300 | f->range_tail = new_node; | |
2301 | } | |
2302 | /* A very interesting can of worms. */ | |
2303 | n->range_next = new_node; | |
2304 | n->data_size = offset - n->data_offset; | |
2305 | if (new_node->fm) | |
2306 | jffs_add_node(new_node); | |
2307 | else { | |
2308 | D1(printk(KERN_WARNING "jffs_delete_data(): Splitting an empty node (file hold).\n!")); | |
2309 | D1(printk(KERN_WARNING "FIXME: Did dwmw2 do the right thing here?\n")); | |
2310 | } | |
2311 | n = new_node->range_next; | |
2312 | remove_size = 0; | |
2313 | } | |
2314 | else { | |
2315 | /* No. No need to split the node. Just remove | |
2316 | the end of the node. */ | |
2317 | int r = min(n->data_offset + n->data_size | |
2318 | - offset, remove_size); | |
2319 | n->data_size -= r; | |
2320 | remove_size -= r; | |
2321 | n = n->range_next; | |
2322 | } | |
2323 | } | |
2324 | ||
2325 | /* Remove as many nodes as necessary. */ | |
2326 | while (n && remove_size) { | |
2327 | if (n->data_size <= remove_size) { | |
2328 | struct jffs_node *p = n; | |
2329 | remove_size -= n->data_size; | |
2330 | n = n->range_next; | |
2331 | D3(printk("jffs_delete_data(): Removing node: " | |
2332 | "ino: %u, version: %u%s\n", | |
2333 | p->ino, p->version, | |
2334 | (p->fm ? "" : " (virtual)"))); | |
2335 | if (p->fm) { | |
2336 | jffs_fmfree(f->c->fmc, p->fm, p); | |
2337 | } | |
2338 | jffs_unlink_node_from_range_list(f, p); | |
2339 | jffs_unlink_node_from_version_list(f, p); | |
2340 | jffs_free_node(p); | |
2341 | DJM(no_jffs_node--); | |
2342 | } | |
2343 | else { | |
2344 | n->data_size -= remove_size; | |
2345 | n->fm_offset += remove_size; | |
2346 | n->data_offset -= (node->removed_size - remove_size); | |
2347 | n = n->range_next; | |
2348 | break; | |
2349 | } | |
2350 | } | |
2351 | ||
2352 | /* Adjust the following nodes' information about offsets etc. */ | |
2353 | while (n && node->removed_size) { | |
2354 | n->data_offset -= node->removed_size; | |
2355 | n = n->range_next; | |
2356 | } | |
2357 | ||
2358 | if (node->removed_size > (f->size - node->data_offset)) { | |
2359 | /* It's possible that the removed_size is in fact | |
2360 | * greater than the amount of data we actually thought | |
2361 | * were present in the first place - some of the nodes | |
2362 | * which this node originally obsoleted may already have | |
2363 | * been deleted from the flash by subsequent garbage | |
2364 | * collection. | |
2365 | * | |
2366 | * If this is the case, don't let f->size go negative. | |
2367 | * Bad things would happen :) | |
2368 | */ | |
2369 | f->size = node->data_offset; | |
2370 | } else { | |
2371 | f->size -= node->removed_size; | |
2372 | } | |
2373 | D3(printk("jffs_delete_data(): f->size = %d\n", f->size)); | |
2374 | return 0; | |
2375 | } /* jffs_delete_data() */ | |
2376 | ||
2377 | ||
2378 | /* Insert some data into a file. Prior to the call to this function, | |
2379 | jffs_delete_data should be called. */ | |
2380 | static int | |
2381 | jffs_insert_data(struct jffs_file *f, struct jffs_node *node) | |
2382 | { | |
2383 | D3(printk("jffs_insert_data(): node->data_offset = %u, " | |
2384 | "node->data_size = %u, f->size = %u\n", | |
2385 | node->data_offset, node->data_size, f->size)); | |
2386 | ||
2387 | /* Find the position where we should insert data. */ | |
2388 | retry: | |
2389 | if (node->data_offset == f->size) { | |
2390 | /* A simple append. This is the most common operation. */ | |
2391 | node->range_next = NULL; | |
2392 | node->range_prev = f->range_tail; | |
2393 | if (node->range_prev) { | |
2394 | node->range_prev->range_next = node; | |
2395 | } | |
2396 | f->range_tail = node; | |
2397 | f->size += node->data_size; | |
2398 | if (!f->range_head) { | |
2399 | f->range_head = node; | |
2400 | } | |
2401 | } | |
2402 | else if (node->data_offset < f->size) { | |
2403 | /* Trying to insert data into the middle of the file. This | |
2404 | means no problem because jffs_delete_data() has already | |
2405 | prepared the range list for us. */ | |
2406 | struct jffs_node *n; | |
2407 | ||
2408 | /* Find the correct place for the insertion and then insert | |
2409 | the node. */ | |
2410 | for (n = f->range_head; n; n = n->range_next) { | |
2411 | D2(printk("Cool stuff's happening!\n")); | |
2412 | ||
2413 | if (n->data_offset == node->data_offset) { | |
2414 | node->range_prev = n->range_prev; | |
2415 | if (node->range_prev) { | |
2416 | node->range_prev->range_next = node; | |
2417 | } | |
2418 | else { | |
2419 | f->range_head = node; | |
2420 | } | |
2421 | node->range_next = n; | |
2422 | n->range_prev = node; | |
2423 | break; | |
2424 | } | |
2425 | ASSERT(else if (n->data_offset + n->data_size > | |
2426 | node->data_offset) { | |
2427 | printk(KERN_ERR "jffs_insert_data(): " | |
2428 | "Couldn't find a place to insert " | |
2429 | "the data!\n"); | |
2430 | return -1; | |
2431 | }); | |
2432 | } | |
2433 | ||
2434 | /* Adjust later nodes' offsets etc. */ | |
2435 | n = node->range_next; | |
2436 | while (n) { | |
2437 | n->data_offset += node->data_size; | |
2438 | n = n->range_next; | |
2439 | } | |
2440 | f->size += node->data_size; | |
2441 | } | |
2442 | else if (node->data_offset > f->size) { | |
2443 | /* Okay. This is tricky. This means that we want to insert | |
2444 | data at a place that is beyond the limits of the file as | |
2445 | it is constructed right now. This is actually a common | |
2446 | event that for instance could occur during the mounting | |
2447 | of the file system if a large file have been truncated, | |
2448 | rewritten and then only partially garbage collected. */ | |
2449 | ||
2450 | struct jffs_node *n; | |
2451 | ||
2452 | /* We need a place holder for the data that is missing in | |
2453 | front of this insertion. This "virtual node" will not | |
2454 | be associated with any space on the flash device. */ | |
2455 | struct jffs_node *virtual_node; | |
2456 | if (!(virtual_node = jffs_alloc_node())) { | |
2457 | return -ENOMEM; | |
2458 | } | |
2459 | ||
2460 | D(printk("jffs_insert_data: Inserting a virtual node.\n")); | |
2461 | D(printk(" node->data_offset = %u\n", node->data_offset)); | |
2462 | D(printk(" f->size = %u\n", f->size)); | |
2463 | ||
2464 | virtual_node->ino = node->ino; | |
2465 | virtual_node->version = node->version; | |
2466 | virtual_node->removed_size = 0; | |
2467 | virtual_node->fm_offset = 0; | |
2468 | virtual_node->name_size = 0; | |
2469 | virtual_node->fm = NULL; /* This is a virtual data holder. */ | |
2470 | virtual_node->version_prev = NULL; | |
2471 | virtual_node->version_next = NULL; | |
2472 | virtual_node->range_next = NULL; | |
2473 | ||
2474 | /* Are there any data at all in the file yet? */ | |
2475 | if (f->range_head) { | |
2476 | virtual_node->data_offset | |
2477 | = f->range_tail->data_offset | |
2478 | + f->range_tail->data_size; | |
2479 | virtual_node->data_size | |
2480 | = node->data_offset - virtual_node->data_offset; | |
2481 | virtual_node->range_prev = f->range_tail; | |
2482 | f->range_tail->range_next = virtual_node; | |
2483 | } | |
2484 | else { | |
2485 | virtual_node->data_offset = 0; | |
2486 | virtual_node->data_size = node->data_offset; | |
2487 | virtual_node->range_prev = NULL; | |
2488 | f->range_head = virtual_node; | |
2489 | } | |
2490 | ||
2491 | f->range_tail = virtual_node; | |
2492 | f->size += virtual_node->data_size; | |
2493 | ||
2494 | /* Insert this virtual node in the version list as well. */ | |
2495 | for (n = f->version_head; n ; n = n->version_next) { | |
2496 | if (n->version == virtual_node->version) { | |
2497 | virtual_node->version_prev = n->version_prev; | |
2498 | n->version_prev = virtual_node; | |
2499 | if (virtual_node->version_prev) { | |
2500 | virtual_node->version_prev | |
2501 | ->version_next = virtual_node; | |
2502 | } | |
2503 | else { | |
2504 | f->version_head = virtual_node; | |
2505 | } | |
2506 | virtual_node->version_next = n; | |
2507 | break; | |
2508 | } | |
2509 | } | |
2510 | ||
2511 | D(jffs_print_node(virtual_node)); | |
2512 | ||
2513 | /* Make a new try to insert the node. */ | |
2514 | goto retry; | |
2515 | } | |
2516 | ||
2517 | D3(printk("jffs_insert_data(): f->size = %d\n", f->size)); | |
2518 | return 0; | |
2519 | } | |
2520 | ||
2521 | ||
2522 | /* A new node (with data) has been added to the file and now the range | |
2523 | list has to be modified. */ | |
2524 | static int | |
2525 | jffs_update_file(struct jffs_file *f, struct jffs_node *node) | |
2526 | { | |
2527 | int err; | |
2528 | ||
2529 | D3(printk("jffs_update_file(): ino: %u, version: %u\n", | |
2530 | f->ino, node->version)); | |
2531 | ||
2532 | if (node->data_size == 0) { | |
2533 | if (node->removed_size == 0) { | |
2534 | /* data_offset == X */ | |
2535 | /* data_size == 0 */ | |
2536 | /* remove_size == 0 */ | |
2537 | } | |
2538 | else { | |
2539 | /* data_offset == X */ | |
2540 | /* data_size == 0 */ | |
2541 | /* remove_size != 0 */ | |
2542 | if ((err = jffs_delete_data(f, node)) < 0) { | |
2543 | return err; | |
2544 | } | |
2545 | } | |
2546 | } | |
2547 | else { | |
2548 | /* data_offset == X */ | |
2549 | /* data_size != 0 */ | |
2550 | /* remove_size == Y */ | |
2551 | if ((err = jffs_delete_data(f, node)) < 0) { | |
2552 | return err; | |
2553 | } | |
2554 | if ((err = jffs_insert_data(f, node)) < 0) { | |
2555 | return err; | |
2556 | } | |
2557 | } | |
2558 | return 0; | |
2559 | } | |
2560 | ||
1da177e4 LT |
2561 | /* Print the contents of a file. */ |
2562 | #if 0 | |
2563 | int | |
2564 | jffs_print_file(struct jffs_file *f) | |
2565 | { | |
2566 | D(int i); | |
2567 | D(printk("jffs_file: 0x%p\n", f)); | |
2568 | D(printk("{\n")); | |
2569 | D(printk(" 0x%08x, /* ino */\n", f->ino)); | |
2570 | D(printk(" 0x%08x, /* pino */\n", f->pino)); | |
2571 | D(printk(" 0x%08x, /* mode */\n", f->mode)); | |
2572 | D(printk(" 0x%04x, /* uid */\n", f->uid)); | |
2573 | D(printk(" 0x%04x, /* gid */\n", f->gid)); | |
2574 | D(printk(" 0x%08x, /* atime */\n", f->atime)); | |
2575 | D(printk(" 0x%08x, /* mtime */\n", f->mtime)); | |
2576 | D(printk(" 0x%08x, /* ctime */\n", f->ctime)); | |
2577 | D(printk(" 0x%02x, /* nsize */\n", f->nsize)); | |
2578 | D(printk(" 0x%02x, /* nlink */\n", f->nlink)); | |
2579 | D(printk(" 0x%02x, /* deleted */\n", f->deleted)); | |
2580 | D(printk(" \"%s\", ", (f->name ? f->name : ""))); | |
2581 | D(for (i = strlen(f->name ? f->name : ""); i < 8; ++i) { | |
2582 | printk(" "); | |
2583 | }); | |
2584 | D(printk("/* name */\n")); | |
2585 | D(printk(" 0x%08x, /* size */\n", f->size)); | |
2586 | D(printk(" 0x%08x, /* highest_version */\n", | |
2587 | f->highest_version)); | |
2588 | D(printk(" 0x%p, /* c */\n", f->c)); | |
2589 | D(printk(" 0x%p, /* parent */\n", f->parent)); | |
2590 | D(printk(" 0x%p, /* children */\n", f->children)); | |
2591 | D(printk(" 0x%p, /* sibling_prev */\n", f->sibling_prev)); | |
2592 | D(printk(" 0x%p, /* sibling_next */\n", f->sibling_next)); | |
2593 | D(printk(" 0x%p, /* hash_prev */\n", f->hash.prev)); | |
2594 | D(printk(" 0x%p, /* hash_next */\n", f->hash.next)); | |
2595 | D(printk(" 0x%p, /* range_head */\n", f->range_head)); | |
2596 | D(printk(" 0x%p, /* range_tail */\n", f->range_tail)); | |
2597 | D(printk(" 0x%p, /* version_head */\n", f->version_head)); | |
2598 | D(printk(" 0x%p, /* version_tail */\n", f->version_tail)); | |
2599 | D(printk("}\n")); | |
2600 | return 0; | |
2601 | } | |
2602 | #endif /* 0 */ | |
2603 | ||
2604 | void | |
2605 | jffs_print_hash_table(struct jffs_control *c) | |
2606 | { | |
2607 | int i; | |
2608 | ||
2609 | printk("JFFS: Dumping the file system's hash table...\n"); | |
2610 | for (i = 0; i < c->hash_len; i++) { | |
216d81bb DP |
2611 | struct jffs_file *f; |
2612 | list_for_each_entry(f, &c->hash[i], hash) { | |
1da177e4 LT |
2613 | printk("*** c->hash[%u]: \"%s\" " |
2614 | "(ino: %u, pino: %u)\n", | |
2615 | i, (f->name ? f->name : ""), | |
2616 | f->ino, f->pino); | |
2617 | } | |
2618 | } | |
2619 | } | |
2620 | ||
2621 | ||
2622 | void | |
2623 | jffs_print_tree(struct jffs_file *first_file, int indent) | |
2624 | { | |
2625 | struct jffs_file *f; | |
2626 | char *space; | |
2627 | int dir; | |
2628 | ||
2629 | if (!first_file) { | |
2630 | return; | |
2631 | } | |
2632 | ||
2633 | if (!(space = (char *) kmalloc(indent + 1, GFP_KERNEL))) { | |
2634 | printk("jffs_print_tree(): Out of memory!\n"); | |
2635 | return; | |
2636 | } | |
2637 | ||
2638 | memset(space, ' ', indent); | |
2639 | space[indent] = '\0'; | |
2640 | ||
2641 | for (f = first_file; f; f = f->sibling_next) { | |
2642 | dir = S_ISDIR(f->mode); | |
2643 | printk("%s%s%s (ino: %u, highest_version: %u, size: %u)\n", | |
2644 | space, (f->name ? f->name : ""), (dir ? "/" : ""), | |
2645 | f->ino, f->highest_version, f->size); | |
2646 | if (dir) { | |
2647 | jffs_print_tree(f->children, indent + 2); | |
2648 | } | |
2649 | } | |
2650 | ||
2651 | kfree(space); | |
2652 | } | |
2653 | ||
2654 | ||
2655 | #if defined(JFFS_MEMORY_DEBUG) && JFFS_MEMORY_DEBUG | |
2656 | void | |
2657 | jffs_print_memory_allocation_statistics(void) | |
2658 | { | |
2659 | static long printout; | |
2660 | printk("________ Memory printout #%ld ________\n", ++printout); | |
2661 | printk("no_jffs_file = %ld\n", no_jffs_file); | |
2662 | printk("no_jffs_node = %ld\n", no_jffs_node); | |
2663 | printk("no_jffs_control = %ld\n", no_jffs_control); | |
2664 | printk("no_jffs_raw_inode = %ld\n", no_jffs_raw_inode); | |
2665 | printk("no_jffs_node_ref = %ld\n", no_jffs_node_ref); | |
2666 | printk("no_jffs_fm = %ld\n", no_jffs_fm); | |
2667 | printk("no_jffs_fmcontrol = %ld\n", no_jffs_fmcontrol); | |
2668 | printk("no_hash = %ld\n", no_hash); | |
2669 | printk("no_name = %ld\n", no_name); | |
2670 | printk("\n"); | |
2671 | } | |
2672 | #endif | |
2673 | ||
2674 | ||
2675 | /* Rewrite `size' bytes, and begin at `node'. */ | |
2676 | static int | |
2677 | jffs_rewrite_data(struct jffs_file *f, struct jffs_node *node, __u32 size) | |
2678 | { | |
2679 | struct jffs_control *c = f->c; | |
2680 | struct jffs_fmcontrol *fmc = c->fmc; | |
2681 | struct jffs_raw_inode raw_inode; | |
2682 | struct jffs_node *new_node; | |
2683 | struct jffs_fm *fm; | |
2684 | __u32 pos; | |
2685 | __u32 pos_dchksum; | |
2686 | __u32 total_name_size; | |
2687 | __u32 total_data_size; | |
2688 | __u32 total_size; | |
2689 | int err; | |
2690 | ||
2691 | D1(printk("***jffs_rewrite_data(): node: %u, name: \"%s\", size: %u\n", | |
2692 | f->ino, (f->name ? f->name : "(null)"), size)); | |
2693 | ||
2694 | /* Create and initialize the new node. */ | |
2695 | if (!(new_node = jffs_alloc_node())) { | |
2696 | D(printk("jffs_rewrite_data(): " | |
2697 | "Failed to allocate node.\n")); | |
2698 | return -ENOMEM; | |
2699 | } | |
2700 | DJM(no_jffs_node++); | |
2701 | new_node->data_offset = node->data_offset; | |
2702 | new_node->removed_size = size; | |
2703 | total_name_size = JFFS_PAD(f->nsize); | |
2704 | total_data_size = JFFS_PAD(size); | |
2705 | total_size = sizeof(struct jffs_raw_inode) | |
2706 | + total_name_size + total_data_size; | |
2707 | new_node->fm_offset = sizeof(struct jffs_raw_inode) | |
2708 | + total_name_size; | |
2709 | ||
2710 | retry: | |
2711 | jffs_fm_write_lock(fmc); | |
2712 | err = 0; | |
2713 | ||
2714 | if ((err = jffs_fmalloc(fmc, total_size, new_node, &fm)) < 0) { | |
2715 | DJM(no_jffs_node--); | |
2716 | jffs_fm_write_unlock(fmc); | |
2717 | D(printk("jffs_rewrite_data(): Failed to allocate fm.\n")); | |
2718 | jffs_free_node(new_node); | |
2719 | return err; | |
2720 | } | |
2721 | else if (!fm->nodes) { | |
2722 | /* The jffs_fm struct that we got is not big enough. */ | |
2723 | /* This should never happen, because we deal with this case | |
2724 | in jffs_garbage_collect_next().*/ | |
2725 | printk(KERN_WARNING "jffs_rewrite_data(): Allocated node is too small (%d bytes of %d)\n", fm->size, total_size); | |
2726 | if ((err = jffs_write_dummy_node(c, fm)) < 0) { | |
2727 | D(printk("jffs_rewrite_data(): " | |
2728 | "jffs_write_dummy_node() Failed!\n")); | |
2729 | } else { | |
2730 | err = -ENOSPC; | |
2731 | } | |
2732 | DJM(no_jffs_fm--); | |
2733 | jffs_fm_write_unlock(fmc); | |
2734 | kfree(fm); | |
2735 | ||
2736 | return err; | |
2737 | } | |
2738 | new_node->fm = fm; | |
2739 | ||
2740 | /* Initialize the raw inode. */ | |
2741 | raw_inode.magic = JFFS_MAGIC_BITMASK; | |
2742 | raw_inode.ino = f->ino; | |
2743 | raw_inode.pino = f->pino; | |
2744 | raw_inode.version = f->highest_version + 1; | |
2745 | raw_inode.mode = f->mode; | |
2746 | raw_inode.uid = f->uid; | |
2747 | raw_inode.gid = f->gid; | |
2748 | raw_inode.atime = f->atime; | |
2749 | raw_inode.mtime = f->mtime; | |
2750 | raw_inode.ctime = f->ctime; | |
2751 | raw_inode.offset = node->data_offset; | |
2752 | raw_inode.dsize = size; | |
2753 | raw_inode.rsize = size; | |
2754 | raw_inode.nsize = f->nsize; | |
2755 | raw_inode.nlink = f->nlink; | |
2756 | raw_inode.spare = 0; | |
2757 | raw_inode.rename = 0; | |
2758 | raw_inode.deleted = f->deleted; | |
2759 | raw_inode.accurate = 0xff; | |
2760 | raw_inode.dchksum = 0; | |
2761 | raw_inode.nchksum = 0; | |
2762 | ||
2763 | pos = new_node->fm->offset; | |
2764 | pos_dchksum = pos +JFFS_RAW_INODE_DCHKSUM_OFFSET; | |
2765 | ||
2766 | D3(printk("jffs_rewrite_data(): Writing this raw inode " | |
2767 | "to pos 0x%ul.\n", pos)); | |
2768 | D3(jffs_print_raw_inode(&raw_inode)); | |
2769 | ||
2770 | if ((err = flash_safe_write(fmc->mtd, pos, | |
2771 | (u_char *) &raw_inode, | |
2772 | sizeof(struct jffs_raw_inode) | |
2773 | - sizeof(__u32) | |
2774 | - sizeof(__u16) - sizeof(__u16))) < 0) { | |
2775 | jffs_fmfree_partly(fmc, fm, | |
2776 | total_name_size + total_data_size); | |
2777 | jffs_fm_write_unlock(fmc); | |
2778 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Write error during " | |
2779 | "rewrite. (raw inode)\n"); | |
2780 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Now retrying " | |
2781 | "rewrite. (raw inode)\n"); | |
2782 | goto retry; | |
2783 | } | |
2784 | pos += sizeof(struct jffs_raw_inode); | |
2785 | ||
2786 | /* Write the name to the flash memory. */ | |
2787 | if (f->nsize) { | |
2788 | D3(printk("jffs_rewrite_data(): Writing name \"%s\" to " | |
2789 | "pos 0x%ul.\n", f->name, (unsigned int) pos)); | |
2790 | if ((err = flash_safe_write(fmc->mtd, pos, | |
2791 | (u_char *)f->name, | |
2792 | f->nsize)) < 0) { | |
2793 | jffs_fmfree_partly(fmc, fm, total_data_size); | |
2794 | jffs_fm_write_unlock(fmc); | |
2795 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Write " | |
2796 | "error during rewrite. (name)\n"); | |
2797 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Now retrying " | |
2798 | "rewrite. (name)\n"); | |
2799 | goto retry; | |
2800 | } | |
2801 | pos += total_name_size; | |
2802 | raw_inode.nchksum = jffs_checksum(f->name, f->nsize); | |
2803 | } | |
2804 | ||
2805 | /* Write the data. */ | |
2806 | if (size) { | |
2807 | int r; | |
2808 | unsigned char *page; | |
2809 | __u32 offset = node->data_offset; | |
2810 | ||
2811 | if (!(page = (unsigned char *)__get_free_page(GFP_KERNEL))) { | |
2812 | jffs_fmfree_partly(fmc, fm, 0); | |
2813 | return -1; | |
2814 | } | |
2815 | ||
2816 | while (size) { | |
2817 | __u32 s = min(size, (__u32)PAGE_SIZE); | |
2818 | if ((r = jffs_read_data(f, (char *)page, | |
2819 | offset, s)) < s) { | |
2820 | free_page((unsigned long)page); | |
2821 | jffs_fmfree_partly(fmc, fm, 0); | |
2822 | jffs_fm_write_unlock(fmc); | |
2823 | printk(KERN_ERR "JFFS: jffs_rewrite_data: " | |
2824 | "jffs_read_data() " | |
2825 | "failed! (r = %d)\n", r); | |
2826 | return -1; | |
2827 | } | |
2828 | if ((err = flash_safe_write(fmc->mtd, | |
2829 | pos, page, r)) < 0) { | |
2830 | free_page((unsigned long)page); | |
2831 | jffs_fmfree_partly(fmc, fm, 0); | |
2832 | jffs_fm_write_unlock(fmc); | |
2833 | printk(KERN_ERR "JFFS: jffs_rewrite_data: " | |
2834 | "Write error during rewrite. " | |
2835 | "(data)\n"); | |
2836 | goto retry; | |
2837 | } | |
2838 | pos += r; | |
2839 | size -= r; | |
2840 | offset += r; | |
2841 | raw_inode.dchksum += jffs_checksum(page, r); | |
2842 | } | |
2843 | ||
2844 | free_page((unsigned long)page); | |
2845 | } | |
2846 | ||
2847 | raw_inode.accurate = 0; | |
2848 | raw_inode.chksum = jffs_checksum(&raw_inode, | |
2849 | sizeof(struct jffs_raw_inode) | |
2850 | - sizeof(__u16)); | |
2851 | ||
2852 | /* Add the checksum. */ | |
2853 | if ((err | |
2854 | = flash_safe_write(fmc->mtd, pos_dchksum, | |
2855 | &((u_char *) | |
2856 | &raw_inode)[JFFS_RAW_INODE_DCHKSUM_OFFSET], | |
2857 | sizeof(__u32) + sizeof(__u16) | |
2858 | + sizeof(__u16))) < 0) { | |
2859 | jffs_fmfree_partly(fmc, fm, 0); | |
2860 | jffs_fm_write_unlock(fmc); | |
2861 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Write error during " | |
2862 | "rewrite. (checksum)\n"); | |
2863 | goto retry; | |
2864 | } | |
2865 | ||
2866 | /* Now make the file system aware of the newly written node. */ | |
2867 | jffs_insert_node(c, f, &raw_inode, f->name, new_node); | |
2868 | jffs_fm_write_unlock(fmc); | |
2869 | ||
2870 | D3(printk("jffs_rewrite_data(): Leaving...\n")); | |
2871 | return 0; | |
2872 | } /* jffs_rewrite_data() */ | |
2873 | ||
2874 | ||
2875 | /* jffs_garbage_collect_next implements one step in the garbage collect | |
2876 | process and is often called multiple times at each occasion of a | |
2877 | garbage collect. */ | |
2878 | ||
2879 | static int | |
2880 | jffs_garbage_collect_next(struct jffs_control *c) | |
2881 | { | |
2882 | struct jffs_fmcontrol *fmc = c->fmc; | |
2883 | struct jffs_node *node; | |
2884 | struct jffs_file *f; | |
2885 | int err = 0; | |
2886 | __u32 size; | |
2887 | __u32 data_size; | |
2888 | __u32 total_name_size; | |
2889 | __u32 extra_available; | |
2890 | __u32 space_needed; | |
2891 | __u32 free_chunk_size1 = jffs_free_size1(fmc); | |
2892 | D2(__u32 free_chunk_size2 = jffs_free_size2(fmc)); | |
2893 | ||
2894 | /* Get the oldest node in the flash. */ | |
2895 | node = jffs_get_oldest_node(fmc); | |
2896 | ASSERT(if (!node) { | |
2897 | printk(KERN_ERR "JFFS: jffs_garbage_collect_next: " | |
2898 | "No oldest node found!\n"); | |
2899 | err = -1; | |
2900 | goto jffs_garbage_collect_next_end; | |
2901 | ||
2902 | ||
2903 | }); | |
2904 | ||
2905 | /* Find its corresponding file too. */ | |
2906 | f = jffs_find_file(c, node->ino); | |
2907 | ||
2908 | if (!f) { | |
2909 | printk (KERN_ERR "JFFS: jffs_garbage_collect_next: " | |
2910 | "No file to garbage collect! " | |
2911 | "(ino = 0x%08x)\n", node->ino); | |
2912 | /* FIXME: Free the offending node and recover. */ | |
2913 | err = -1; | |
2914 | goto jffs_garbage_collect_next_end; | |
2915 | } | |
2916 | ||
2917 | /* We always write out the name. Theoretically, we don't need | |
2918 | to, but for now it's easier - because otherwise we'd have | |
2919 | to keep track of how many times the current name exists on | |
2920 | the flash and make sure it never reaches zero. | |
2921 | ||
2922 | The current approach means that would be possible to cause | |
2923 | the GC to end up eating its tail by writing lots of nodes | |
2924 | with no name for it to garbage-collect. Hence the change in | |
2925 | inode.c to write names with _every_ node. | |
2926 | ||
2927 | It sucks, but it _should_ work. | |
2928 | */ | |
2929 | total_name_size = JFFS_PAD(f->nsize); | |
2930 | ||
2931 | D1(printk("jffs_garbage_collect_next(): \"%s\", " | |
2932 | "ino: %u, version: %u, location 0x%x, dsize %u\n", | |
2933 | (f->name ? f->name : ""), node->ino, node->version, | |
2934 | node->fm->offset, node->data_size)); | |
2935 | ||
2936 | /* Compute how many data it's possible to rewrite at the moment. */ | |
2937 | data_size = f->size - node->data_offset; | |
2938 | ||
2939 | /* And from that, the total size of the chunk we want to write */ | |
2940 | size = sizeof(struct jffs_raw_inode) + total_name_size | |
2941 | + data_size + JFFS_GET_PAD_BYTES(data_size); | |
2942 | ||
2943 | /* If that's more than max_chunk_size, reduce it accordingly */ | |
2944 | if (size > fmc->max_chunk_size) { | |
2945 | size = fmc->max_chunk_size; | |
2946 | data_size = size - sizeof(struct jffs_raw_inode) | |
2947 | - total_name_size; | |
2948 | } | |
2949 | ||
2950 | /* If we're asking to take up more space than free_chunk_size1 | |
2951 | but we _could_ fit in it, shrink accordingly. | |
2952 | */ | |
2953 | if (size > free_chunk_size1) { | |
2954 | ||
2955 | if (free_chunk_size1 < | |
2956 | (sizeof(struct jffs_raw_inode) + total_name_size + BLOCK_SIZE)){ | |
2957 | /* The space left is too small to be of any | |
2958 | use really. */ | |
2959 | struct jffs_fm *dirty_fm | |
2960 | = jffs_fmalloced(fmc, | |
2961 | fmc->tail->offset + fmc->tail->size, | |
2962 | free_chunk_size1, NULL); | |
2963 | if (!dirty_fm) { | |
2964 | printk(KERN_ERR "JFFS: " | |
2965 | "jffs_garbage_collect_next: " | |
2966 | "Failed to allocate `dirty' " | |
2967 | "flash memory!\n"); | |
2968 | err = -1; | |
2969 | goto jffs_garbage_collect_next_end; | |
2970 | } | |
2971 | D1(printk("Dirtying end of flash - too small\n")); | |
2972 | jffs_write_dummy_node(c, dirty_fm); | |
2973 | err = 0; | |
2974 | goto jffs_garbage_collect_next_end; | |
2975 | } | |
2976 | D1(printk("Reducing size of new node from %d to %d to avoid " | |
2977 | " exceeding free_chunk_size1\n", | |
2978 | size, free_chunk_size1)); | |
2979 | ||
2980 | size = free_chunk_size1; | |
2981 | data_size = size - sizeof(struct jffs_raw_inode) | |
2982 | - total_name_size; | |
2983 | } | |
2984 | ||
2985 | ||
2986 | /* Calculate the amount of space needed to hold the nodes | |
2987 | which are remaining in the tail */ | |
2988 | space_needed = fmc->min_free_size - (node->fm->offset % fmc->sector_size); | |
2989 | ||
2990 | /* From that, calculate how much 'extra' space we can use to | |
2991 | increase the size of the node we're writing from the size | |
2992 | of the node we're obsoleting | |
2993 | */ | |
2994 | if (space_needed > fmc->free_size) { | |
2995 | /* If we've gone below min_free_size for some reason, | |
2996 | don't fuck up. This is why we have | |
2997 | min_free_size > sector_size. Whinge about it though, | |
2998 | just so I can convince myself my maths is right. | |
2999 | */ | |
3000 | D1(printk(KERN_WARNING "jffs_garbage_collect_next(): " | |
3001 | "space_needed %d exceeded free_size %d\n", | |
3002 | space_needed, fmc->free_size)); | |
3003 | extra_available = 0; | |
3004 | } else { | |
3005 | extra_available = fmc->free_size - space_needed; | |
3006 | } | |
3007 | ||
3008 | /* Check that we don't use up any more 'extra' space than | |
3009 | what's available */ | |
3010 | if (size > JFFS_PAD(node->data_size) + total_name_size + | |
3011 | sizeof(struct jffs_raw_inode) + extra_available) { | |
3012 | D1(printk("Reducing size of new node from %d to %ld to avoid " | |
3013 | "catching our tail\n", size, | |
3014 | (long) (JFFS_PAD(node->data_size) + JFFS_PAD(node->name_size) + | |
3015 | sizeof(struct jffs_raw_inode) + extra_available))); | |
3016 | D1(printk("space_needed = %d, extra_available = %d\n", | |
3017 | space_needed, extra_available)); | |
3018 | ||
3019 | size = JFFS_PAD(node->data_size) + total_name_size + | |
3020 | sizeof(struct jffs_raw_inode) + extra_available; | |
3021 | data_size = size - sizeof(struct jffs_raw_inode) | |
3022 | - total_name_size; | |
3023 | }; | |
3024 | ||
3025 | D2(printk(" total_name_size: %u\n", total_name_size)); | |
3026 | D2(printk(" data_size: %u\n", data_size)); | |
3027 | D2(printk(" size: %u\n", size)); | |
3028 | D2(printk(" f->nsize: %u\n", f->nsize)); | |
3029 | D2(printk(" f->size: %u\n", f->size)); | |
3030 | D2(printk(" node->data_offset: %u\n", node->data_offset)); | |
3031 | D2(printk(" free_chunk_size1: %u\n", free_chunk_size1)); | |
3032 | D2(printk(" free_chunk_size2: %u\n", free_chunk_size2)); | |
3033 | D2(printk(" node->fm->offset: 0x%08x\n", node->fm->offset)); | |
3034 | ||
3035 | if ((err = jffs_rewrite_data(f, node, data_size))) { | |
3036 | printk(KERN_WARNING "jffs_rewrite_data() failed: %d\n", err); | |
3037 | return err; | |
3038 | } | |
3039 | ||
3040 | jffs_garbage_collect_next_end: | |
3041 | D3(printk("jffs_garbage_collect_next: Leaving...\n")); | |
3042 | return err; | |
3043 | } /* jffs_garbage_collect_next */ | |
3044 | ||
3045 | ||
3046 | /* If an obsolete node is partly going to be erased due to garbage | |
3047 | collection, the part that isn't going to be erased must be filled | |
3048 | with zeroes so that the scan of the flash will work smoothly next | |
3049 | time. (The data in the file could for instance be a JFFS image | |
3050 | which could cause enormous confusion during a scan of the flash | |
3051 | device if we didn't do this.) | |
3052 | There are two phases in this procedure: First, the clearing of | |
3053 | the name and data parts of the node. Second, possibly also clearing | |
3054 | a part of the raw inode as well. If the box is power cycled during | |
3055 | the first phase, only the checksum of this node-to-be-cleared-at- | |
3056 | the-end will be wrong. If the box is power cycled during, or after, | |
3057 | the clearing of the raw inode, the information like the length of | |
3058 | the name and data parts are zeroed. The next time the box is | |
3059 | powered up, the scanning algorithm manages this faulty data too | |
3060 | because: | |
3061 | ||
3062 | - The checksum is invalid and thus the raw inode must be discarded | |
3063 | in any case. | |
3064 | - If the lengths of the data part or the name part are zeroed, the | |
3065 | scanning just continues after the raw inode. But after the inode | |
3066 | the scanning procedure just finds zeroes which is the same as | |
3067 | dirt. | |
3068 | ||
3069 | So, in the end, this could never fail. :-) Even if it does fail, | |
3070 | the scanning algorithm should manage that too. */ | |
3071 | ||
3072 | static int | |
3073 | jffs_clear_end_of_node(struct jffs_control *c, __u32 erase_size) | |
3074 | { | |
3075 | struct jffs_fm *fm; | |
3076 | struct jffs_fmcontrol *fmc = c->fmc; | |
3077 | __u32 zero_offset; | |
3078 | __u32 zero_size; | |
3079 | __u32 zero_offset_data; | |
3080 | __u32 zero_size_data; | |
3081 | __u32 cutting_raw_inode = 0; | |
3082 | ||
3083 | if (!(fm = jffs_cut_node(fmc, erase_size))) { | |
3084 | D3(printk("jffs_clear_end_of_node(): fm == NULL\n")); | |
3085 | return 0; | |
3086 | } | |
3087 | ||
3088 | /* Where and how much shall we clear? */ | |
3089 | zero_offset = fmc->head->offset + erase_size; | |
3090 | zero_size = fm->offset + fm->size - zero_offset; | |
3091 | ||
3092 | /* Do we have to clear the raw_inode explicitly? */ | |
3093 | if (fm->size - zero_size < sizeof(struct jffs_raw_inode)) { | |
3094 | cutting_raw_inode = sizeof(struct jffs_raw_inode) | |
3095 | - (fm->size - zero_size); | |
3096 | } | |
3097 | ||
3098 | /* First, clear the name and data fields. */ | |
3099 | zero_offset_data = zero_offset + cutting_raw_inode; | |
3100 | zero_size_data = zero_size - cutting_raw_inode; | |
3101 | flash_safe_acquire(fmc->mtd); | |
3102 | flash_memset(fmc->mtd, zero_offset_data, 0, zero_size_data); | |
3103 | flash_safe_release(fmc->mtd); | |
3104 | ||
3105 | /* Should we clear a part of the raw inode? */ | |
3106 | if (cutting_raw_inode) { | |
3107 | /* I guess it is ok to clear the raw inode in this order. */ | |
3108 | flash_safe_acquire(fmc->mtd); | |
3109 | flash_memset(fmc->mtd, zero_offset, 0, | |
3110 | cutting_raw_inode); | |
3111 | flash_safe_release(fmc->mtd); | |
3112 | } | |
3113 | ||
3114 | return 0; | |
3115 | } /* jffs_clear_end_of_node() */ | |
3116 | ||
3117 | /* Try to erase as much as possible of the dirt in the flash memory. */ | |
3118 | static long | |
3119 | jffs_try_to_erase(struct jffs_control *c) | |
3120 | { | |
3121 | struct jffs_fmcontrol *fmc = c->fmc; | |
3122 | long erase_size; | |
3123 | int err; | |
3124 | __u32 offset; | |
3125 | ||
3126 | D3(printk("jffs_try_to_erase()\n")); | |
3127 | ||
3128 | erase_size = jffs_erasable_size(fmc); | |
3129 | ||
3130 | D2(printk("jffs_try_to_erase(): erase_size = %ld\n", erase_size)); | |
3131 | ||
3132 | if (erase_size == 0) { | |
3133 | return 0; | |
3134 | } | |
3135 | else if (erase_size < 0) { | |
3136 | printk(KERN_ERR "JFFS: jffs_try_to_erase: " | |
3137 | "jffs_erasable_size returned %ld.\n", erase_size); | |
3138 | return erase_size; | |
3139 | } | |
3140 | ||
3141 | if ((err = jffs_clear_end_of_node(c, erase_size)) < 0) { | |
3142 | printk(KERN_ERR "JFFS: jffs_try_to_erase: " | |
3143 | "Clearing of node failed.\n"); | |
3144 | return err; | |
3145 | } | |
3146 | ||
3147 | offset = fmc->head->offset; | |
3148 | ||
3149 | /* Now, let's try to do the erase. */ | |
3150 | if ((err = flash_erase_region(fmc->mtd, | |
3151 | offset, erase_size)) < 0) { | |
3152 | printk(KERN_ERR "JFFS: Erase of flash failed. " | |
3153 | "offset = %u, erase_size = %ld\n", | |
3154 | offset, erase_size); | |
3155 | /* XXX: Here we should allocate this area as dirty | |
3156 | with jffs_fmalloced or something similar. Now | |
3157 | we just report the error. */ | |
3158 | return err; | |
3159 | } | |
3160 | ||
3161 | #if 0 | |
3162 | /* Check if the erased sectors really got erased. */ | |
3163 | { | |
3164 | __u32 pos; | |
3165 | __u32 end; | |
3166 | ||
3167 | pos = (__u32)flash_get_direct_pointer(to_kdev_t(c->sb->s_dev), offset); | |
3168 | end = pos + erase_size; | |
3169 | ||
3170 | D2(printk("JFFS: Checking erased sector(s)...\n")); | |
3171 | ||
3172 | flash_safe_acquire(fmc->mtd); | |
3173 | ||
3174 | for (; pos < end; pos += 4) { | |
3175 | if (*(__u32 *)pos != JFFS_EMPTY_BITMASK) { | |
3176 | printk("JFFS: Erase failed! pos = 0x%lx\n", | |
3177 | (long)pos); | |
3178 | jffs_hexdump(fmc->mtd, pos, | |
3179 | jffs_min(256, end - pos)); | |
3180 | err = -1; | |
3181 | break; | |
3182 | } | |
3183 | } | |
3184 | ||
3185 | flash_safe_release(fmc->mtd); | |
3186 | ||
3187 | if (!err) { | |
3188 | D2(printk("JFFS: Erase succeeded.\n")); | |
3189 | } | |
3190 | else { | |
3191 | /* XXX: Here we should allocate the memory | |
3192 | with jffs_fmalloced() in order to prevent | |
3193 | JFFS from using this area accidentally. */ | |
3194 | return err; | |
3195 | } | |
3196 | } | |
3197 | #endif | |
3198 | ||
3199 | /* Update the flash memory data structures. */ | |
3200 | jffs_sync_erase(fmc, erase_size); | |
3201 | ||
3202 | return erase_size; | |
3203 | } | |
3204 | ||
3205 | ||
3206 | /* There are different criteria that should trigger a garbage collect: | |
3207 | ||
3208 | 1. There is too much dirt in the memory. | |
3209 | 2. The free space is becoming small. | |
3210 | 3. There are many versions of a node. | |
3211 | ||
3212 | The garbage collect should always be done in a manner that guarantees | |
3213 | that future garbage collects cannot be locked. E.g. Rewritten chunks | |
3214 | should not be too large (span more than one sector in the flash memory | |
3215 | for exemple). Of course there is a limit on how intelligent this garbage | |
3216 | collection can be. */ | |
3217 | ||
3218 | ||
3219 | static int | |
3220 | jffs_garbage_collect_now(struct jffs_control *c) | |
3221 | { | |
3222 | struct jffs_fmcontrol *fmc = c->fmc; | |
3223 | long erased = 0; | |
3224 | int result = 0; | |
3225 | D1(int i = 1); | |
3226 | D2(printk("***jffs_garbage_collect_now(): fmc->dirty_size = %u, fmc->free_size = 0x%x\n, fcs1=0x%x, fcs2=0x%x", | |
3227 | fmc->dirty_size, fmc->free_size, jffs_free_size1(fmc), jffs_free_size2(fmc))); | |
3228 | D2(jffs_print_fmcontrol(fmc)); | |
3229 | ||
3230 | // down(&fmc->gclock); | |
3231 | ||
3232 | /* If it is possible to garbage collect, do so. */ | |
3233 | ||
3234 | while (erased == 0) { | |
3235 | D1(printk("***jffs_garbage_collect_now(): round #%u, " | |
3236 | "fmc->dirty_size = %u\n", i++, fmc->dirty_size)); | |
3237 | D2(jffs_print_fmcontrol(fmc)); | |
3238 | ||
3239 | if ((erased = jffs_try_to_erase(c)) < 0) { | |
3240 | printk(KERN_WARNING "JFFS: Error in " | |
3241 | "garbage collector.\n"); | |
3242 | result = erased; | |
3243 | goto gc_end; | |
3244 | } | |
3245 | if (erased) | |
3246 | break; | |
3247 | ||
3248 | if (fmc->free_size == 0) { | |
3249 | /* Argh */ | |
3250 | printk(KERN_ERR "jffs_garbage_collect_now(): free_size == 0. This is BAD.\n"); | |
3251 | result = -ENOSPC; | |
3252 | break; | |
3253 | } | |
3254 | ||
3255 | if (fmc->dirty_size < fmc->sector_size) { | |
3256 | /* Actually, we _may_ have been able to free some, | |
3257 | * if there are many overlapping nodes which aren't | |
3258 | * actually marked dirty because they still have | |
3259 | * some valid data in each. | |
3260 | */ | |
3261 | result = -ENOSPC; | |
3262 | break; | |
3263 | } | |
3264 | ||
3265 | /* Let's dare to make a garbage collect. */ | |
3266 | if ((result = jffs_garbage_collect_next(c)) < 0) { | |
3267 | printk(KERN_ERR "JFFS: Something " | |
3268 | "has gone seriously wrong " | |
3269 | "with a garbage collect.\n"); | |
3270 | goto gc_end; | |
3271 | } | |
3272 | ||
3273 | D1(printk(" jffs_garbage_collect_now(): erased: %ld\n", erased)); | |
3274 | DJM(jffs_print_memory_allocation_statistics()); | |
3275 | } | |
3276 | ||
3277 | gc_end: | |
3278 | // up(&fmc->gclock); | |
3279 | ||
3280 | D3(printk(" jffs_garbage_collect_now(): Leaving...\n")); | |
3281 | D1(if (erased) { | |
3282 | printk("jffs_g_c_now(): erased = %ld\n", erased); | |
3283 | jffs_print_fmcontrol(fmc); | |
3284 | }); | |
3285 | ||
3286 | if (!erased && !result) | |
3287 | return -ENOSPC; | |
3288 | ||
3289 | return result; | |
3290 | } /* jffs_garbage_collect_now() */ | |
3291 | ||
3292 | ||
3293 | /* Determine if it is reasonable to start garbage collection. | |
3294 | We start a gc pass if either: | |
3295 | - The number of free bytes < MIN_FREE_BYTES && at least one | |
3296 | block is dirty, OR | |
3297 | - The number of dirty bytes > MAX_DIRTY_BYTES | |
3298 | */ | |
3299 | static inline int thread_should_wake (struct jffs_control *c) | |
3300 | { | |
3301 | D1(printk (KERN_NOTICE "thread_should_wake(): free=%d, dirty=%d, blocksize=%d.\n", | |
3302 | c->fmc->free_size, c->fmc->dirty_size, c->fmc->sector_size)); | |
3303 | ||
3304 | /* If there's not enough dirty space to free a block, there's no point. */ | |
3305 | if (c->fmc->dirty_size < c->fmc->sector_size) { | |
3306 | D2(printk(KERN_NOTICE "thread_should_wake(): Not waking. Insufficient dirty space\n")); | |
3307 | return 0; | |
3308 | } | |
3309 | #if 1 | |
3310 | /* If there is too much RAM used by the various structures, GC */ | |
3311 | if (jffs_get_node_inuse() > (c->fmc->used_size/c->fmc->max_chunk_size * 5 + jffs_get_file_count() * 2 + 50)) { | |
3312 | /* FIXME: Provide proof that this test can be satisfied. We | |
3313 | don't want a filesystem doing endless GC just because this | |
3314 | condition cannot ever be false. | |
3315 | */ | |
3316 | D2(printk(KERN_NOTICE "thread_should_wake(): Waking due to number of nodes\n")); | |
3317 | return 1; | |
3318 | } | |
3319 | #endif | |
3320 | /* If there are fewer free bytes than the threshold, GC */ | |
3321 | if (c->fmc->free_size < c->gc_minfree_threshold) { | |
3322 | D2(printk(KERN_NOTICE "thread_should_wake(): Waking due to insufficent free space\n")); | |
3323 | return 1; | |
3324 | } | |
3325 | /* If there are more dirty bytes than the threshold, GC */ | |
3326 | if (c->fmc->dirty_size > c->gc_maxdirty_threshold) { | |
3327 | D2(printk(KERN_NOTICE "thread_should_wake(): Waking due to excessive dirty space\n")); | |
3328 | return 1; | |
3329 | } | |
3330 | /* FIXME: What about the "There are many versions of a node" condition? */ | |
3331 | ||
3332 | return 0; | |
3333 | } | |
3334 | ||
3335 | ||
3336 | void jffs_garbage_collect_trigger(struct jffs_control *c) | |
3337 | { | |
3338 | /* NOTE: We rely on the fact that we have the BKL here. | |
3339 | * Otherwise, the gc_task could go away between the check | |
3340 | * and the wake_up_process() | |
3341 | */ | |
3342 | if (c->gc_task && thread_should_wake(c)) | |
3343 | send_sig(SIGHUP, c->gc_task, 1); | |
3344 | } | |
3345 | ||
3346 | ||
3347 | /* Kernel threads take (void *) as arguments. Thus we pass | |
3348 | the jffs_control data as a (void *) and then cast it. */ | |
3349 | int | |
3350 | jffs_garbage_collect_thread(void *ptr) | |
3351 | { | |
3352 | struct jffs_control *c = (struct jffs_control *) ptr; | |
3353 | struct jffs_fmcontrol *fmc = c->fmc; | |
3354 | long erased; | |
3355 | int result = 0; | |
3356 | D1(int i = 1); | |
3357 | ||
3358 | daemonize("jffs_gcd"); | |
3359 | ||
3360 | c->gc_task = current; | |
3361 | ||
3362 | lock_kernel(); | |
3363 | init_completion(&c->gc_thread_comp); /* barrier */ | |
3364 | spin_lock_irq(¤t->sighand->siglock); | |
3365 | siginitsetinv (¤t->blocked, sigmask(SIGHUP) | sigmask(SIGKILL) | sigmask(SIGSTOP) | sigmask(SIGCONT)); | |
3366 | recalc_sigpending(); | |
3367 | spin_unlock_irq(¤t->sighand->siglock); | |
3368 | ||
3369 | D1(printk (KERN_NOTICE "jffs_garbage_collect_thread(): Starting infinite loop.\n")); | |
3370 | ||
3371 | for (;;) { | |
3372 | ||
3373 | /* See if we need to start gc. If we don't, go to sleep. | |
3374 | ||
3375 | Current implementation is a BAD THING(tm). If we try | |
3376 | to unmount the FS, the unmount operation will sleep waiting | |
3377 | for this thread to exit. We need to arrange to send it a | |
3378 | sig before the umount process sleeps. | |
3379 | */ | |
3380 | ||
3381 | if (!thread_should_wake(c)) | |
3382 | set_current_state (TASK_INTERRUPTIBLE); | |
3383 | ||
3384 | schedule(); /* Yes, we do this even if we want to go | |
3385 | on immediately - we're a low priority | |
3386 | background task. */ | |
3387 | ||
3388 | /* Put_super will send a SIGKILL and then wait on the sem. | |
3389 | */ | |
3390 | while (signal_pending(current)) { | |
3391 | siginfo_t info; | |
3392 | unsigned long signr = 0; | |
3393 | ||
ef2a701d NC |
3394 | if (try_to_freeze()) |
3395 | continue; | |
3396 | ||
1da177e4 LT |
3397 | spin_lock_irq(¤t->sighand->siglock); |
3398 | signr = dequeue_signal(current, ¤t->blocked, &info); | |
3399 | spin_unlock_irq(¤t->sighand->siglock); | |
3400 | ||
3401 | switch(signr) { | |
3402 | case SIGSTOP: | |
3403 | D1(printk("jffs_garbage_collect_thread(): SIGSTOP received.\n")); | |
3404 | set_current_state(TASK_STOPPED); | |
3405 | schedule(); | |
3406 | break; | |
3407 | ||
3408 | case SIGKILL: | |
3409 | D1(printk("jffs_garbage_collect_thread(): SIGKILL received.\n")); | |
3410 | c->gc_task = NULL; | |
3411 | complete_and_exit(&c->gc_thread_comp, 0); | |
3412 | } | |
3413 | } | |
3414 | ||
3415 | ||
3416 | D1(printk (KERN_NOTICE "jffs_garbage_collect_thread(): collecting.\n")); | |
3417 | ||
3418 | D3(printk (KERN_NOTICE "g_c_thread(): down biglock\n")); | |
1eb0d670 | 3419 | mutex_lock(&fmc->biglock); |
1da177e4 LT |
3420 | |
3421 | D1(printk("***jffs_garbage_collect_thread(): round #%u, " | |
3422 | "fmc->dirty_size = %u\n", i++, fmc->dirty_size)); | |
3423 | D2(jffs_print_fmcontrol(fmc)); | |
3424 | ||
3425 | if ((erased = jffs_try_to_erase(c)) < 0) { | |
3426 | printk(KERN_WARNING "JFFS: Error in " | |
3427 | "garbage collector: %ld.\n", erased); | |
3428 | } | |
3429 | ||
3430 | if (erased) | |
3431 | goto gc_end; | |
3432 | ||
3433 | if (fmc->free_size == 0) { | |
3434 | /* Argh. Might as well commit suicide. */ | |
3435 | printk(KERN_ERR "jffs_garbage_collect_thread(): free_size == 0. This is BAD.\n"); | |
3436 | send_sig(SIGQUIT, c->gc_task, 1); | |
3437 | // panic() | |
3438 | goto gc_end; | |
3439 | } | |
3440 | ||
3441 | /* Let's dare to make a garbage collect. */ | |
3442 | if ((result = jffs_garbage_collect_next(c)) < 0) { | |
3443 | printk(KERN_ERR "JFFS: Something " | |
3444 | "has gone seriously wrong " | |
3445 | "with a garbage collect: %d\n", result); | |
3446 | } | |
3447 | ||
3448 | gc_end: | |
3449 | D3(printk (KERN_NOTICE "g_c_thread(): up biglock\n")); | |
1eb0d670 | 3450 | mutex_unlock(&fmc->biglock); |
1da177e4 LT |
3451 | } /* for (;;) */ |
3452 | } /* jffs_garbage_collect_thread() */ |