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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> | |
65 | #include <asm/semaphore.h> | |
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 | ||
178 | #endif | |
179 | ||
180 | #define flash_safe_acquire(arg) | |
181 | #define flash_safe_release(arg) | |
182 | ||
183 | ||
184 | static int | |
185 | flash_safe_read(struct mtd_info *mtd, loff_t from, | |
186 | u_char *buf, size_t count) | |
187 | { | |
188 | size_t retlen; | |
189 | int res; | |
190 | ||
191 | D3(printk(KERN_NOTICE "flash_safe_read(%p, %08x, %p, %08x)\n", | |
192 | mtd, (unsigned int) from, buf, count)); | |
193 | ||
194 | res = MTD_READ(mtd, from, count, &retlen, buf); | |
195 | if (retlen != count) { | |
196 | panic("Didn't read all bytes in flash_safe_read(). Returned %d\n", res); | |
197 | } | |
198 | return res?res:retlen; | |
199 | } | |
200 | ||
201 | ||
202 | static __u32 | |
203 | flash_read_u32(struct mtd_info *mtd, loff_t from) | |
204 | { | |
205 | size_t retlen; | |
206 | __u32 ret; | |
207 | int res; | |
208 | ||
209 | res = MTD_READ(mtd, from, 4, &retlen, (unsigned char *)&ret); | |
210 | if (retlen != 4) { | |
211 | printk("Didn't read all bytes in flash_read_u32(). Returned %d\n", res); | |
212 | return 0; | |
213 | } | |
214 | ||
215 | return ret; | |
216 | } | |
217 | ||
218 | ||
219 | static int | |
220 | flash_safe_write(struct mtd_info *mtd, loff_t to, | |
221 | const u_char *buf, size_t count) | |
222 | { | |
223 | size_t retlen; | |
224 | int res; | |
225 | ||
226 | D3(printk(KERN_NOTICE "flash_safe_write(%p, %08x, %p, %08x)\n", | |
227 | mtd, (unsigned int) to, buf, count)); | |
228 | ||
229 | res = MTD_WRITE(mtd, to, count, &retlen, buf); | |
230 | if (retlen != count) { | |
231 | printk("Didn't write all bytes in flash_safe_write(). Returned %d\n", res); | |
232 | } | |
233 | return res?res:retlen; | |
234 | } | |
235 | ||
236 | ||
237 | static int | |
238 | flash_safe_writev(struct mtd_info *mtd, const struct kvec *vecs, | |
239 | unsigned long iovec_cnt, loff_t to) | |
240 | { | |
241 | size_t retlen, retlen_a; | |
242 | int i; | |
243 | int res; | |
244 | ||
245 | D3(printk(KERN_NOTICE "flash_safe_writev(%p, %08x, %p)\n", | |
246 | mtd, (unsigned int) to, vecs)); | |
247 | ||
248 | if (mtd->writev) { | |
249 | res = MTD_WRITEV(mtd, vecs, iovec_cnt, to, &retlen); | |
250 | return res ? res : retlen; | |
251 | } | |
252 | /* Not implemented writev. Repeatedly use write - on the not so | |
253 | unreasonable assumption that the mtd driver doesn't care how | |
254 | many write cycles we use. */ | |
255 | res=0; | |
256 | retlen=0; | |
257 | ||
258 | for (i=0; !res && i<iovec_cnt; i++) { | |
259 | res = MTD_WRITE(mtd, to, vecs[i].iov_len, &retlen_a, vecs[i].iov_base); | |
260 | if (retlen_a != vecs[i].iov_len) { | |
261 | printk("Didn't write all bytes in flash_safe_writev(). Returned %d\n", res); | |
262 | if (i != iovec_cnt-1) | |
263 | return -EIO; | |
264 | } | |
265 | /* If res is non-zero, retlen_a is undefined, but we don't | |
266 | care because in that case it's not going to be | |
267 | returned anyway. | |
268 | */ | |
269 | to += retlen_a; | |
270 | retlen += retlen_a; | |
271 | } | |
272 | return res?res:retlen; | |
273 | } | |
274 | ||
275 | ||
276 | static int | |
277 | flash_memset(struct mtd_info *mtd, loff_t to, | |
278 | const u_char c, size_t size) | |
279 | { | |
280 | static unsigned char pattern[64]; | |
281 | int i; | |
282 | ||
283 | /* fill up pattern */ | |
284 | ||
285 | for(i = 0; i < 64; i++) | |
286 | pattern[i] = c; | |
287 | ||
288 | /* write as many 64-byte chunks as we can */ | |
289 | ||
290 | while (size >= 64) { | |
291 | flash_safe_write(mtd, to, pattern, 64); | |
292 | size -= 64; | |
293 | to += 64; | |
294 | } | |
295 | ||
296 | /* and the rest */ | |
297 | ||
298 | if(size) | |
299 | flash_safe_write(mtd, to, pattern, size); | |
300 | ||
301 | return size; | |
302 | } | |
303 | ||
304 | ||
305 | static void | |
306 | intrep_erase_callback(struct erase_info *done) | |
307 | { | |
308 | wait_queue_head_t *wait_q; | |
309 | ||
310 | wait_q = (wait_queue_head_t *)done->priv; | |
311 | ||
312 | wake_up(wait_q); | |
313 | } | |
314 | ||
315 | ||
316 | static int | |
317 | flash_erase_region(struct mtd_info *mtd, loff_t start, | |
318 | size_t size) | |
319 | { | |
320 | struct erase_info *erase; | |
321 | DECLARE_WAITQUEUE(wait, current); | |
322 | wait_queue_head_t wait_q; | |
323 | ||
324 | erase = kmalloc(sizeof(struct erase_info), GFP_KERNEL); | |
325 | if (!erase) | |
326 | return -ENOMEM; | |
327 | ||
328 | init_waitqueue_head(&wait_q); | |
329 | ||
330 | erase->mtd = mtd; | |
331 | erase->callback = intrep_erase_callback; | |
332 | erase->addr = start; | |
333 | erase->len = size; | |
334 | erase->priv = (u_long)&wait_q; | |
335 | ||
336 | /* FIXME: Use TASK_INTERRUPTIBLE and deal with being interrupted */ | |
337 | set_current_state(TASK_UNINTERRUPTIBLE); | |
338 | add_wait_queue(&wait_q, &wait); | |
339 | ||
340 | if (MTD_ERASE(mtd, erase) < 0) { | |
341 | set_current_state(TASK_RUNNING); | |
342 | remove_wait_queue(&wait_q, &wait); | |
343 | kfree(erase); | |
344 | ||
345 | printk(KERN_WARNING "flash: erase of region [0x%lx, 0x%lx] " | |
346 | "totally failed\n", (long)start, (long)start + size); | |
347 | ||
348 | return -1; | |
349 | } | |
350 | ||
351 | schedule(); /* Wait for flash to finish. */ | |
352 | remove_wait_queue(&wait_q, &wait); | |
353 | ||
354 | kfree(erase); | |
355 | ||
356 | return 0; | |
357 | } | |
358 | ||
359 | /* This routine calculates checksums in JFFS. */ | |
360 | static __u32 | |
361 | jffs_checksum(const void *data, int size) | |
362 | { | |
363 | __u32 sum = 0; | |
364 | __u8 *ptr = (__u8 *)data; | |
365 | while (size-- > 0) { | |
366 | sum += *ptr++; | |
367 | } | |
368 | D3(printk(", result: 0x%08x\n", sum)); | |
369 | return sum; | |
370 | } | |
371 | ||
372 | ||
373 | static int | |
374 | jffs_checksum_flash(struct mtd_info *mtd, loff_t start, int size, __u32 *result) | |
375 | { | |
376 | __u32 sum = 0; | |
377 | loff_t ptr = start; | |
378 | __u8 *read_buf; | |
379 | int i, length; | |
380 | ||
381 | /* Allocate read buffer */ | |
382 | read_buf = (__u8 *) kmalloc (sizeof(__u8) * 4096, GFP_KERNEL); | |
383 | if (!read_buf) { | |
384 | printk(KERN_NOTICE "kmalloc failed in jffs_checksum_flash()\n"); | |
385 | return -ENOMEM; | |
386 | } | |
387 | /* Loop until checksum done */ | |
388 | while (size) { | |
389 | /* Get amount of data to read */ | |
390 | if (size < 4096) | |
391 | length = size; | |
392 | else | |
393 | length = 4096; | |
394 | ||
395 | /* Perform flash read */ | |
396 | D3(printk(KERN_NOTICE "jffs_checksum_flash\n")); | |
397 | flash_safe_read(mtd, ptr, &read_buf[0], length); | |
398 | ||
399 | /* Compute checksum */ | |
400 | for (i=0; i < length ; i++) | |
401 | sum += read_buf[i]; | |
402 | ||
403 | /* Update pointer and size */ | |
404 | size -= length; | |
405 | ptr += length; | |
406 | } | |
407 | ||
408 | /* Free read buffer */ | |
409 | kfree (read_buf); | |
410 | ||
411 | /* Return result */ | |
412 | D3(printk("checksum result: 0x%08x\n", sum)); | |
413 | *result = sum; | |
414 | return 0; | |
415 | } | |
416 | ||
417 | static __inline__ void jffs_fm_write_lock(struct jffs_fmcontrol *fmc) | |
418 | { | |
419 | // down(&fmc->wlock); | |
420 | } | |
421 | ||
422 | static __inline__ void jffs_fm_write_unlock(struct jffs_fmcontrol *fmc) | |
423 | { | |
424 | // up(&fmc->wlock); | |
425 | } | |
426 | ||
427 | ||
428 | /* Create and initialize a new struct jffs_file. */ | |
429 | static struct jffs_file * | |
430 | jffs_create_file(struct jffs_control *c, | |
431 | const struct jffs_raw_inode *raw_inode) | |
432 | { | |
433 | struct jffs_file *f; | |
434 | ||
435 | if (!(f = (struct jffs_file *)kmalloc(sizeof(struct jffs_file), | |
436 | GFP_KERNEL))) { | |
437 | D(printk("jffs_create_file(): Failed!\n")); | |
438 | return NULL; | |
439 | } | |
440 | no_jffs_file++; | |
441 | memset(f, 0, sizeof(struct jffs_file)); | |
442 | f->ino = raw_inode->ino; | |
443 | f->pino = raw_inode->pino; | |
444 | f->nlink = raw_inode->nlink; | |
445 | f->deleted = raw_inode->deleted; | |
446 | f->c = c; | |
447 | ||
448 | return f; | |
449 | } | |
450 | ||
451 | ||
452 | /* Build a control block for the file system. */ | |
453 | static struct jffs_control * | |
454 | jffs_create_control(struct super_block *sb) | |
455 | { | |
456 | struct jffs_control *c; | |
457 | register int s = sizeof(struct jffs_control); | |
458 | int i; | |
459 | D(char *t = 0); | |
460 | ||
461 | D2(printk("jffs_create_control()\n")); | |
462 | ||
463 | if (!(c = (struct jffs_control *)kmalloc(s, GFP_KERNEL))) { | |
464 | goto fail_control; | |
465 | } | |
466 | DJM(no_jffs_control++); | |
467 | c->root = NULL; | |
468 | c->gc_task = NULL; | |
469 | c->hash_len = JFFS_HASH_SIZE; | |
470 | s = sizeof(struct list_head) * c->hash_len; | |
471 | if (!(c->hash = (struct list_head *)kmalloc(s, GFP_KERNEL))) { | |
472 | goto fail_hash; | |
473 | } | |
474 | DJM(no_hash++); | |
475 | for (i = 0; i < c->hash_len; i++) | |
476 | INIT_LIST_HEAD(&c->hash[i]); | |
477 | if (!(c->fmc = jffs_build_begin(c, MINOR(sb->s_dev)))) { | |
478 | goto fail_fminit; | |
479 | } | |
480 | c->next_ino = JFFS_MIN_INO + 1; | |
481 | c->delete_list = (struct jffs_delete_list *) 0; | |
482 | return c; | |
483 | ||
484 | fail_fminit: | |
485 | D(t = "c->fmc"); | |
486 | fail_hash: | |
487 | kfree(c); | |
488 | DJM(no_jffs_control--); | |
489 | D(t = t ? t : "c->hash"); | |
490 | fail_control: | |
491 | D(t = t ? t : "control"); | |
492 | D(printk("jffs_create_control(): Allocation failed: (%s)\n", t)); | |
493 | return (struct jffs_control *)0; | |
494 | } | |
495 | ||
496 | ||
497 | /* Clean up all data structures associated with the file system. */ | |
498 | void | |
499 | jffs_cleanup_control(struct jffs_control *c) | |
500 | { | |
501 | D2(printk("jffs_cleanup_control()\n")); | |
502 | ||
503 | if (!c) { | |
504 | D(printk("jffs_cleanup_control(): c == NULL !!!\n")); | |
505 | return; | |
506 | } | |
507 | ||
508 | while (c->delete_list) { | |
509 | struct jffs_delete_list *delete_list_element; | |
510 | delete_list_element = c->delete_list; | |
511 | c->delete_list = c->delete_list->next; | |
512 | kfree(delete_list_element); | |
513 | } | |
514 | ||
515 | /* Free all files and nodes. */ | |
516 | if (c->hash) { | |
517 | jffs_foreach_file(c, jffs_free_node_list); | |
518 | jffs_foreach_file(c, jffs_free_file); | |
519 | kfree(c->hash); | |
520 | DJM(no_hash--); | |
521 | } | |
522 | jffs_cleanup_fmcontrol(c->fmc); | |
523 | kfree(c); | |
524 | DJM(no_jffs_control--); | |
525 | D3(printk("jffs_cleanup_control(): Leaving...\n")); | |
526 | } | |
527 | ||
528 | ||
529 | /* This function adds a virtual root node to the in-RAM representation. | |
530 | Called by jffs_build_fs(). */ | |
531 | static int | |
532 | jffs_add_virtual_root(struct jffs_control *c) | |
533 | { | |
534 | struct jffs_file *root; | |
535 | struct jffs_node *node; | |
536 | ||
537 | D2(printk("jffs_add_virtual_root(): " | |
538 | "Creating a virtual root directory.\n")); | |
539 | ||
540 | if (!(root = (struct jffs_file *)kmalloc(sizeof(struct jffs_file), | |
541 | GFP_KERNEL))) { | |
542 | return -ENOMEM; | |
543 | } | |
544 | no_jffs_file++; | |
545 | if (!(node = jffs_alloc_node())) { | |
546 | kfree(root); | |
547 | no_jffs_file--; | |
548 | return -ENOMEM; | |
549 | } | |
550 | DJM(no_jffs_node++); | |
551 | memset(node, 0, sizeof(struct jffs_node)); | |
552 | node->ino = JFFS_MIN_INO; | |
553 | memset(root, 0, sizeof(struct jffs_file)); | |
554 | root->ino = JFFS_MIN_INO; | |
555 | root->mode = S_IFDIR | S_IRWXU | S_IRGRP | |
556 | | S_IXGRP | S_IROTH | S_IXOTH; | |
557 | root->atime = root->mtime = root->ctime = get_seconds(); | |
558 | root->nlink = 1; | |
559 | root->c = c; | |
560 | root->version_head = root->version_tail = node; | |
561 | jffs_insert_file_into_hash(root); | |
562 | return 0; | |
563 | } | |
564 | ||
565 | ||
566 | /* This is where the file system is built and initialized. */ | |
567 | int | |
568 | jffs_build_fs(struct super_block *sb) | |
569 | { | |
570 | struct jffs_control *c; | |
571 | int err = 0; | |
572 | ||
573 | D2(printk("jffs_build_fs()\n")); | |
574 | ||
575 | if (!(c = jffs_create_control(sb))) { | |
576 | return -ENOMEM; | |
577 | } | |
578 | c->building_fs = 1; | |
579 | c->sb = sb; | |
580 | if ((err = jffs_scan_flash(c)) < 0) { | |
581 | if(err == -EAGAIN){ | |
582 | /* scan_flash() wants us to try once more. A flipping | |
583 | bits sector was detect in the middle of the scan flash. | |
584 | Clean up old allocated memory before going in. | |
585 | */ | |
586 | D1(printk("jffs_build_fs: Cleaning up all control structures," | |
587 | " reallocating them and trying mount again.\n")); | |
588 | jffs_cleanup_control(c); | |
589 | if (!(c = jffs_create_control(sb))) { | |
590 | return -ENOMEM; | |
591 | } | |
592 | c->building_fs = 1; | |
593 | c->sb = sb; | |
594 | ||
595 | if ((err = jffs_scan_flash(c)) < 0) { | |
596 | goto jffs_build_fs_fail; | |
597 | } | |
598 | }else{ | |
599 | goto jffs_build_fs_fail; | |
600 | } | |
601 | } | |
602 | ||
603 | /* Add a virtual root node if no one exists. */ | |
604 | if (!jffs_find_file(c, JFFS_MIN_INO)) { | |
605 | if ((err = jffs_add_virtual_root(c)) < 0) { | |
606 | goto jffs_build_fs_fail; | |
607 | } | |
608 | } | |
609 | ||
610 | while (c->delete_list) { | |
611 | struct jffs_file *f; | |
612 | struct jffs_delete_list *delete_list_element; | |
613 | ||
614 | if ((f = jffs_find_file(c, c->delete_list->ino))) { | |
615 | f->deleted = 1; | |
616 | } | |
617 | delete_list_element = c->delete_list; | |
618 | c->delete_list = c->delete_list->next; | |
619 | kfree(delete_list_element); | |
620 | } | |
621 | ||
622 | /* Remove deleted nodes. */ | |
623 | if ((err = jffs_foreach_file(c, jffs_possibly_delete_file)) < 0) { | |
624 | printk(KERN_ERR "JFFS: Failed to remove deleted nodes.\n"); | |
625 | goto jffs_build_fs_fail; | |
626 | } | |
627 | /* Remove redundant nodes. (We are not interested in the | |
628 | return value in this case.) */ | |
629 | jffs_foreach_file(c, jffs_remove_redundant_nodes); | |
630 | /* Try to build a tree from all the nodes. */ | |
631 | if ((err = jffs_foreach_file(c, jffs_insert_file_into_tree)) < 0) { | |
632 | printk("JFFS: Failed to build tree.\n"); | |
633 | goto jffs_build_fs_fail; | |
634 | } | |
635 | /* Compute the sizes of all files in the filesystem. Adjust if | |
636 | necessary. */ | |
637 | if ((err = jffs_foreach_file(c, jffs_build_file)) < 0) { | |
638 | printk("JFFS: Failed to build file system.\n"); | |
639 | goto jffs_build_fs_fail; | |
640 | } | |
641 | sb->s_fs_info = (void *)c; | |
642 | c->building_fs = 0; | |
643 | ||
644 | D1(jffs_print_hash_table(c)); | |
645 | D1(jffs_print_tree(c->root, 0)); | |
646 | ||
647 | return 0; | |
648 | ||
649 | jffs_build_fs_fail: | |
650 | jffs_cleanup_control(c); | |
651 | return err; | |
652 | } /* jffs_build_fs() */ | |
653 | ||
654 | ||
655 | /* | |
656 | This checks for sectors that were being erased in their previous | |
657 | lifetimes and for some reason or the other (power fail etc.), | |
658 | the erase cycles never completed. | |
659 | As the flash array would have reverted back to read status, | |
660 | these sectors are detected by the symptom of the "flipping bits", | |
661 | i.e. bits being read back differently from the same location in | |
662 | flash if read multiple times. | |
663 | The only solution to this is to re-erase the entire | |
664 | sector. | |
665 | Unfortunately detecting "flipping bits" is not a simple exercise | |
666 | as a bit may be read back at 1 or 0 depending on the alignment | |
667 | of the stars in the universe. | |
668 | The level of confidence is in direct proportion to the number of | |
669 | scans done. By power fail testing I (Vipin) have been able to | |
670 | proove that reading twice is not enough. | |
671 | Maybe 4 times? Change NUM_REREADS to a higher number if you want | |
672 | a (even) higher degree of confidence in your mount process. | |
673 | A higher number would of course slow down your mount. | |
674 | */ | |
675 | static int check_partly_erased_sectors(struct jffs_fmcontrol *fmc){ | |
676 | ||
677 | #define NUM_REREADS 4 /* see note above */ | |
678 | #define READ_AHEAD_BYTES 4096 /* must be a multiple of 4, | |
679 | usually set to kernel page size */ | |
680 | ||
681 | __u8 *read_buf1; | |
682 | __u8 *read_buf2; | |
683 | ||
684 | int err = 0; | |
685 | int retlen; | |
686 | int i; | |
687 | int cnt; | |
688 | __u32 offset; | |
689 | loff_t pos = 0; | |
690 | loff_t end = fmc->flash_size; | |
691 | ||
692 | ||
693 | /* Allocate read buffers */ | |
694 | read_buf1 = (__u8 *) kmalloc (sizeof(__u8) * READ_AHEAD_BYTES, GFP_KERNEL); | |
695 | if (!read_buf1) | |
696 | return -ENOMEM; | |
697 | ||
698 | read_buf2 = (__u8 *) kmalloc (sizeof(__u8) * READ_AHEAD_BYTES, GFP_KERNEL); | |
699 | if (!read_buf2) { | |
700 | kfree(read_buf1); | |
701 | return -ENOMEM; | |
702 | } | |
703 | ||
704 | CHECK_NEXT: | |
705 | while(pos < end){ | |
706 | ||
707 | D1(printk("check_partly_erased_sector():checking sector which contains" | |
708 | " offset 0x%x for flipping bits..\n", (__u32)pos)); | |
709 | ||
710 | retlen = flash_safe_read(fmc->mtd, pos, | |
711 | &read_buf1[0], READ_AHEAD_BYTES); | |
712 | retlen &= ~3; | |
713 | ||
714 | for(cnt = 0; cnt < NUM_REREADS; cnt++){ | |
715 | (void)flash_safe_read(fmc->mtd, pos, | |
716 | &read_buf2[0], READ_AHEAD_BYTES); | |
717 | ||
718 | for (i=0 ; i < retlen ; i+=4) { | |
719 | /* buffers MUST match, double word for word! */ | |
720 | if(*((__u32 *) &read_buf1[i]) != | |
721 | *((__u32 *) &read_buf2[i]) | |
722 | ){ | |
723 | /* flipping bits detected, time to erase sector */ | |
724 | /* This will help us log some statistics etc. */ | |
725 | D1(printk("Flipping bits detected in re-read round:%i of %i\n", | |
726 | cnt, NUM_REREADS)); | |
727 | D1(printk("check_partly_erased_sectors:flipping bits detected" | |
728 | " @offset:0x%x(0x%x!=0x%x)\n", | |
729 | (__u32)pos+i, *((__u32 *) &read_buf1[i]), | |
730 | *((__u32 *) &read_buf2[i]))); | |
731 | ||
732 | /* calculate start of present sector */ | |
733 | offset = (((__u32)pos+i)/(__u32)fmc->sector_size) * (__u32)fmc->sector_size; | |
734 | ||
735 | D1(printk("check_partly_erased_sector():erasing sector starting 0x%x.\n", | |
736 | offset)); | |
737 | ||
738 | if (flash_erase_region(fmc->mtd, | |
739 | offset, fmc->sector_size) < 0) { | |
740 | printk(KERN_ERR "JFFS: Erase of flash failed. " | |
741 | "offset = %u, erase_size = %d\n", | |
742 | offset , fmc->sector_size); | |
743 | ||
744 | err = -EIO; | |
745 | goto returnBack; | |
746 | ||
747 | }else{ | |
748 | D1(printk("JFFS: Erase of flash sector @0x%x successful.\n", | |
749 | offset)); | |
750 | /* skip ahead to the next sector */ | |
751 | pos = (((__u32)pos+i)/(__u32)fmc->sector_size) * (__u32)fmc->sector_size; | |
752 | pos += fmc->sector_size; | |
753 | goto CHECK_NEXT; | |
754 | } | |
755 | } | |
756 | } | |
757 | } | |
758 | pos += READ_AHEAD_BYTES; | |
759 | } | |
760 | ||
761 | returnBack: | |
762 | kfree(read_buf1); | |
763 | kfree(read_buf2); | |
764 | ||
765 | D2(printk("check_partly_erased_sector():Done checking all sectors till offset 0x%x for flipping bits.\n", | |
766 | (__u32)pos)); | |
767 | ||
768 | return err; | |
769 | ||
770 | }/* end check_partly_erased_sectors() */ | |
771 | ||
772 | ||
773 | ||
774 | /* Scan the whole flash memory in order to find all nodes in the | |
775 | file systems. */ | |
776 | static int | |
777 | jffs_scan_flash(struct jffs_control *c) | |
778 | { | |
779 | char name[JFFS_MAX_NAME_LEN + 2]; | |
780 | struct jffs_raw_inode raw_inode; | |
781 | struct jffs_node *node = NULL; | |
782 | struct jffs_fmcontrol *fmc = c->fmc; | |
783 | __u32 checksum; | |
784 | __u8 tmp_accurate; | |
785 | __u16 tmp_chksum; | |
786 | __u32 deleted_file; | |
787 | loff_t pos = 0; | |
788 | loff_t start; | |
789 | loff_t test_start; | |
790 | loff_t end = fmc->flash_size; | |
791 | __u8 *read_buf; | |
792 | int i, len, retlen; | |
793 | __u32 offset; | |
794 | ||
795 | __u32 free_chunk_size1; | |
796 | __u32 free_chunk_size2; | |
797 | ||
798 | ||
799 | #define NUMFREEALLOWED 2 /* 2 chunks of at least erase size space allowed */ | |
800 | int num_free_space = 0; /* Flag err if more than TWO | |
801 | free blocks found. This is NOT allowed | |
802 | by the current jffs design. | |
803 | */ | |
804 | int num_free_spc_not_accp = 0; /* For debugging purposed keep count | |
805 | of how much free space was rejected and | |
806 | marked dirty | |
807 | */ | |
808 | ||
809 | D1(printk("jffs_scan_flash(): start pos = 0x%lx, end = 0x%lx\n", | |
810 | (long)pos, (long)end)); | |
811 | ||
812 | flash_safe_acquire(fmc->mtd); | |
813 | ||
814 | /* | |
815 | check and make sure that any sector does not suffer | |
816 | from the "partly erased, bit flipping syndrome" (TM Vipin :) | |
817 | If so, offending sectors will be erased. | |
818 | */ | |
819 | if(check_partly_erased_sectors(fmc) < 0){ | |
820 | ||
821 | flash_safe_release(fmc->mtd); | |
822 | return -EIO; /* bad, bad, bad error. Cannot continue.*/ | |
823 | } | |
824 | ||
825 | /* Allocate read buffer */ | |
826 | read_buf = (__u8 *) kmalloc (sizeof(__u8) * 4096, GFP_KERNEL); | |
827 | if (!read_buf) { | |
828 | flash_safe_release(fmc->mtd); | |
829 | return -ENOMEM; | |
830 | } | |
831 | ||
832 | /* Start the scan. */ | |
833 | while (pos < end) { | |
834 | deleted_file = 0; | |
835 | ||
836 | /* Remember the position from where we started this scan. */ | |
837 | start = pos; | |
838 | ||
839 | switch (flash_read_u32(fmc->mtd, pos)) { | |
840 | case JFFS_EMPTY_BITMASK: | |
841 | /* We have found 0xffffffff at this position. We have to | |
842 | scan the rest of the flash till the end or till | |
843 | something else than 0xffffffff is found. | |
844 | Keep going till we do not find JFFS_EMPTY_BITMASK | |
845 | anymore */ | |
846 | ||
847 | D1(printk("jffs_scan_flash(): 0xffffffff at pos 0x%lx.\n", | |
848 | (long)pos)); | |
849 | ||
850 | while(pos < end){ | |
851 | ||
852 | len = end - pos < 4096 ? end - pos : 4096; | |
853 | ||
854 | retlen = flash_safe_read(fmc->mtd, pos, | |
855 | &read_buf[0], len); | |
856 | ||
857 | retlen &= ~3; | |
858 | ||
859 | for (i=0 ; i < retlen ; i+=4, pos += 4) { | |
860 | if(*((__u32 *) &read_buf[i]) != | |
861 | JFFS_EMPTY_BITMASK) | |
862 | break; | |
863 | } | |
864 | if (i == retlen) | |
865 | continue; | |
866 | else | |
867 | break; | |
868 | } | |
869 | ||
870 | D1(printk("jffs_scan_flash():0xffffffff ended at pos 0x%lx.\n", | |
871 | (long)pos)); | |
872 | ||
873 | /* If some free space ends in the middle of a sector, | |
874 | treat it as dirty rather than clean. | |
875 | This is to handle the case where one thread | |
876 | allocated space for a node, but didn't get to | |
877 | actually _write_ it before power was lost, leaving | |
878 | a gap in the log. Shifting all node writes into | |
879 | a single kernel thread will fix the original problem. | |
880 | */ | |
881 | if ((__u32) pos % fmc->sector_size) { | |
882 | /* If there was free space in previous | |
883 | sectors, don't mark that dirty too - | |
884 | only from the beginning of this sector | |
885 | (or from start) | |
886 | */ | |
887 | ||
888 | test_start = pos & ~(fmc->sector_size-1); /* end of last sector */ | |
889 | ||
890 | if (start < test_start) { | |
891 | ||
892 | /* free space started in the previous sector! */ | |
893 | ||
894 | if((num_free_space < NUMFREEALLOWED) && | |
895 | ((unsigned int)(test_start - start) >= fmc->sector_size)){ | |
896 | ||
897 | /* | |
898 | Count it in if we are still under NUMFREEALLOWED *and* it is | |
899 | at least 1 erase sector in length. This will keep us from | |
900 | picking any little ole' space as "free". | |
901 | */ | |
902 | ||
903 | D1(printk("Reducing end of free space to 0x%x from 0x%x\n", | |
904 | (unsigned int)test_start, (unsigned int)pos)); | |
905 | ||
906 | D1(printk("Free space accepted: Starting 0x%x for 0x%x bytes\n", | |
907 | (unsigned int) start, | |
908 | (unsigned int)(test_start - start))); | |
909 | ||
910 | /* below, space from "start" to "pos" will be marked dirty. */ | |
911 | start = test_start; | |
912 | ||
913 | /* Being in here means that we have found at least an entire | |
914 | erase sector size of free space ending on a sector boundary. | |
915 | Keep track of free spaces accepted. | |
916 | */ | |
917 | num_free_space++; | |
918 | }else{ | |
919 | num_free_spc_not_accp++; | |
920 | D1(printk("Free space (#%i) found but *Not* accepted: Starting" | |
921 | " 0x%x for 0x%x bytes\n", | |
922 | num_free_spc_not_accp, (unsigned int)start, | |
923 | (unsigned int)((unsigned int)(pos & ~(fmc->sector_size-1)) - (unsigned int)start))); | |
924 | ||
925 | } | |
926 | ||
927 | } | |
928 | if((((__u32)(pos - start)) != 0)){ | |
929 | ||
930 | D1(printk("Dirty space: Starting 0x%x for 0x%x bytes\n", | |
931 | (unsigned int) start, (unsigned int) (pos - start))); | |
932 | jffs_fmalloced(fmc, (__u32) start, | |
933 | (__u32) (pos - start), NULL); | |
934 | }else{ | |
935 | /* "Flipping bits" detected. This means that our scan for them | |
936 | did not catch this offset. See check_partly_erased_sectors() for | |
937 | more info. | |
938 | */ | |
939 | ||
940 | D1(printk("jffs_scan_flash():wants to allocate dirty flash " | |
941 | "space for 0 bytes.\n")); | |
942 | D1(printk("jffs_scan_flash(): Flipping bits! We will free " | |
943 | "all allocated memory, erase this sector and remount\n")); | |
944 | ||
945 | /* calculate start of present sector */ | |
946 | offset = (((__u32)pos)/(__u32)fmc->sector_size) * (__u32)fmc->sector_size; | |
947 | ||
948 | D1(printk("jffs_scan_flash():erasing sector starting 0x%x.\n", | |
949 | offset)); | |
950 | ||
951 | if (flash_erase_region(fmc->mtd, | |
952 | offset, fmc->sector_size) < 0) { | |
953 | printk(KERN_ERR "JFFS: Erase of flash failed. " | |
954 | "offset = %u, erase_size = %d\n", | |
955 | offset , fmc->sector_size); | |
956 | ||
957 | flash_safe_release(fmc->mtd); | |
958 | kfree (read_buf); | |
959 | return -1; /* bad, bad, bad! */ | |
960 | ||
961 | } | |
962 | flash_safe_release(fmc->mtd); | |
963 | kfree (read_buf); | |
964 | ||
965 | return -EAGAIN; /* erased offending sector. Try mount one more time please. */ | |
966 | } | |
967 | }else{ | |
968 | /* Being in here means that we have found free space that ends on an erase sector | |
969 | boundary. | |
970 | Count it in if we are still under NUMFREEALLOWED *and* it is at least 1 erase | |
971 | sector in length. This will keep us from picking any little ole' space as "free". | |
972 | */ | |
973 | if((num_free_space < NUMFREEALLOWED) && | |
974 | ((unsigned int)(pos - start) >= fmc->sector_size)){ | |
975 | /* We really don't do anything to mark space as free, except *not* | |
976 | mark it dirty and just advance the "pos" location pointer. | |
977 | It will automatically be picked up as free space. | |
978 | */ | |
979 | num_free_space++; | |
980 | D1(printk("Free space accepted: Starting 0x%x for 0x%x bytes\n", | |
981 | (unsigned int) start, (unsigned int) (pos - start))); | |
982 | }else{ | |
983 | num_free_spc_not_accp++; | |
984 | D1(printk("Free space (#%i) found but *Not* accepted: Starting " | |
985 | "0x%x for 0x%x bytes\n", num_free_spc_not_accp, | |
986 | (unsigned int) start, | |
987 | (unsigned int) (pos - start))); | |
988 | ||
989 | /* Mark this space as dirty. We already have our free space. */ | |
990 | D1(printk("Dirty space: Starting 0x%x for 0x%x bytes\n", | |
991 | (unsigned int) start, (unsigned int) (pos - start))); | |
992 | jffs_fmalloced(fmc, (__u32) start, | |
993 | (__u32) (pos - start), NULL); | |
994 | } | |
995 | ||
996 | } | |
997 | if(num_free_space > NUMFREEALLOWED){ | |
998 | printk(KERN_WARNING "jffs_scan_flash(): Found free space " | |
999 | "number %i. Only %i free space is allowed.\n", | |
1000 | num_free_space, NUMFREEALLOWED); | |
1001 | } | |
1002 | continue; | |
1003 | ||
1004 | case JFFS_DIRTY_BITMASK: | |
1005 | /* We have found 0x00000000 at this position. Scan as far | |
1006 | as possible to find out how much is dirty. */ | |
1007 | D1(printk("jffs_scan_flash(): 0x00000000 at pos 0x%lx.\n", | |
1008 | (long)pos)); | |
1009 | for (; pos < end | |
1010 | && JFFS_DIRTY_BITMASK == flash_read_u32(fmc->mtd, pos); | |
1011 | pos += 4); | |
1012 | D1(printk("jffs_scan_flash(): 0x00 ended at " | |
1013 | "pos 0x%lx.\n", (long)pos)); | |
1014 | jffs_fmalloced(fmc, (__u32) start, | |
1015 | (__u32) (pos - start), NULL); | |
1016 | continue; | |
1017 | ||
1018 | case JFFS_MAGIC_BITMASK: | |
1019 | /* We have probably found a new raw inode. */ | |
1020 | break; | |
1021 | ||
1022 | default: | |
1023 | bad_inode: | |
1024 | /* We're f*cked. This is not solved yet. We have | |
1025 | to scan for the magic pattern. */ | |
1026 | D1(printk("*************** Dirty flash memory or " | |
1027 | "bad inode: " | |
1028 | "hexdump(pos = 0x%lx, len = 128):\n", | |
1029 | (long)pos)); | |
1030 | D1(jffs_hexdump(fmc->mtd, pos, 128)); | |
1031 | ||
1032 | for (pos += 4; pos < end; pos += 4) { | |
1033 | switch (flash_read_u32(fmc->mtd, pos)) { | |
1034 | case JFFS_MAGIC_BITMASK: | |
1035 | case JFFS_EMPTY_BITMASK: | |
1036 | /* handle these in the main switch() loop */ | |
1037 | goto cont_scan; | |
1038 | ||
1039 | default: | |
1040 | break; | |
1041 | } | |
1042 | } | |
1043 | ||
1044 | cont_scan: | |
1045 | /* First, mark as dirty the region | |
1046 | which really does contain crap. */ | |
1047 | jffs_fmalloced(fmc, (__u32) start, | |
1048 | (__u32) (pos - start), | |
1049 | NULL); | |
1050 | ||
1051 | continue; | |
1052 | }/* switch */ | |
1053 | ||
1054 | /* We have found the beginning of an inode. Create a | |
1055 | node for it unless there already is one available. */ | |
1056 | if (!node) { | |
1057 | if (!(node = jffs_alloc_node())) { | |
1058 | /* Free read buffer */ | |
1059 | kfree (read_buf); | |
1060 | ||
1061 | /* Release the flash device */ | |
1062 | flash_safe_release(fmc->mtd); | |
1063 | ||
1064 | return -ENOMEM; | |
1065 | } | |
1066 | DJM(no_jffs_node++); | |
1067 | } | |
1068 | ||
1069 | /* Read the next raw inode. */ | |
1070 | ||
1071 | flash_safe_read(fmc->mtd, pos, (u_char *) &raw_inode, | |
1072 | sizeof(struct jffs_raw_inode)); | |
1073 | ||
1074 | /* When we compute the checksum for the inode, we never | |
1075 | count the 'accurate' or the 'checksum' fields. */ | |
1076 | tmp_accurate = raw_inode.accurate; | |
1077 | tmp_chksum = raw_inode.chksum; | |
1078 | raw_inode.accurate = 0; | |
1079 | raw_inode.chksum = 0; | |
1080 | checksum = jffs_checksum(&raw_inode, | |
1081 | sizeof(struct jffs_raw_inode)); | |
1082 | raw_inode.accurate = tmp_accurate; | |
1083 | raw_inode.chksum = tmp_chksum; | |
1084 | ||
1085 | D3(printk("*** We have found this raw inode at pos 0x%lx " | |
1086 | "on the flash:\n", (long)pos)); | |
1087 | D3(jffs_print_raw_inode(&raw_inode)); | |
1088 | ||
1089 | if (checksum != raw_inode.chksum) { | |
1090 | D1(printk("jffs_scan_flash(): Bad checksum: " | |
1091 | "checksum = %u, " | |
1092 | "raw_inode.chksum = %u\n", | |
1093 | checksum, raw_inode.chksum)); | |
1094 | pos += sizeof(struct jffs_raw_inode); | |
1095 | jffs_fmalloced(fmc, (__u32) start, | |
1096 | (__u32) (pos - start), NULL); | |
1097 | /* Reuse this unused struct jffs_node. */ | |
1098 | continue; | |
1099 | } | |
1100 | ||
1101 | /* Check the raw inode read so far. Start with the | |
1102 | maximum length of the filename. */ | |
1103 | if (raw_inode.nsize > JFFS_MAX_NAME_LEN) { | |
1104 | printk(KERN_WARNING "jffs_scan_flash: Found a " | |
1105 | "JFFS node with name too large\n"); | |
1106 | goto bad_inode; | |
1107 | } | |
1108 | ||
1109 | if (raw_inode.rename && raw_inode.dsize != sizeof(__u32)) { | |
1110 | printk(KERN_WARNING "jffs_scan_flash: Found a " | |
1111 | "rename node with dsize %u.\n", | |
1112 | raw_inode.dsize); | |
1113 | jffs_print_raw_inode(&raw_inode); | |
1114 | goto bad_inode; | |
1115 | } | |
1116 | ||
1117 | /* The node's data segment should not exceed a | |
1118 | certain length. */ | |
1119 | if (raw_inode.dsize > fmc->max_chunk_size) { | |
1120 | printk(KERN_WARNING "jffs_scan_flash: Found a " | |
1121 | "JFFS node with dsize (0x%x) > max_chunk_size (0x%x)\n", | |
1122 | raw_inode.dsize, fmc->max_chunk_size); | |
1123 | goto bad_inode; | |
1124 | } | |
1125 | ||
1126 | pos += sizeof(struct jffs_raw_inode); | |
1127 | ||
1128 | /* This shouldn't be necessary because a node that | |
1129 | violates the flash boundaries shouldn't be written | |
1130 | in the first place. */ | |
1131 | if (pos >= end) { | |
1132 | goto check_node; | |
1133 | } | |
1134 | ||
1135 | /* Read the name. */ | |
1136 | *name = 0; | |
1137 | if (raw_inode.nsize) { | |
1138 | flash_safe_read(fmc->mtd, pos, name, raw_inode.nsize); | |
1139 | name[raw_inode.nsize] = '\0'; | |
1140 | pos += raw_inode.nsize | |
1141 | + JFFS_GET_PAD_BYTES(raw_inode.nsize); | |
1142 | D3(printk("name == \"%s\"\n", name)); | |
1143 | checksum = jffs_checksum(name, raw_inode.nsize); | |
1144 | if (checksum != raw_inode.nchksum) { | |
1145 | D1(printk("jffs_scan_flash(): Bad checksum: " | |
1146 | "checksum = %u, " | |
1147 | "raw_inode.nchksum = %u\n", | |
1148 | checksum, raw_inode.nchksum)); | |
1149 | jffs_fmalloced(fmc, (__u32) start, | |
1150 | (__u32) (pos - start), NULL); | |
1151 | /* Reuse this unused struct jffs_node. */ | |
1152 | continue; | |
1153 | } | |
1154 | if (pos >= end) { | |
1155 | goto check_node; | |
1156 | } | |
1157 | } | |
1158 | ||
1159 | /* Read the data, if it exists, in order to be sure it | |
1160 | matches the checksum. */ | |
1161 | if (raw_inode.dsize) { | |
1162 | if (raw_inode.rename) { | |
1163 | deleted_file = flash_read_u32(fmc->mtd, pos); | |
1164 | } | |
1165 | if (jffs_checksum_flash(fmc->mtd, pos, raw_inode.dsize, &checksum)) { | |
1166 | printk("jffs_checksum_flash() failed to calculate a checksum\n"); | |
1167 | jffs_fmalloced(fmc, (__u32) start, | |
1168 | (__u32) (pos - start), NULL); | |
1169 | /* Reuse this unused struct jffs_node. */ | |
1170 | continue; | |
1171 | } | |
1172 | pos += raw_inode.dsize | |
1173 | + JFFS_GET_PAD_BYTES(raw_inode.dsize); | |
1174 | ||
1175 | if (checksum != raw_inode.dchksum) { | |
1176 | D1(printk("jffs_scan_flash(): Bad checksum: " | |
1177 | "checksum = %u, " | |
1178 | "raw_inode.dchksum = %u\n", | |
1179 | checksum, raw_inode.dchksum)); | |
1180 | jffs_fmalloced(fmc, (__u32) start, | |
1181 | (__u32) (pos - start), NULL); | |
1182 | /* Reuse this unused struct jffs_node. */ | |
1183 | continue; | |
1184 | } | |
1185 | } | |
1186 | ||
1187 | check_node: | |
1188 | ||
1189 | /* Remember the highest inode number in the whole file | |
1190 | system. This information will be used when assigning | |
1191 | new files new inode numbers. */ | |
1192 | if (c->next_ino <= raw_inode.ino) { | |
1193 | c->next_ino = raw_inode.ino + 1; | |
1194 | } | |
1195 | ||
1196 | if (raw_inode.accurate) { | |
1197 | int err; | |
1198 | node->data_offset = raw_inode.offset; | |
1199 | node->data_size = raw_inode.dsize; | |
1200 | node->removed_size = raw_inode.rsize; | |
1201 | /* Compute the offset to the actual data in the | |
1202 | on-flash node. */ | |
1203 | node->fm_offset | |
1204 | = sizeof(struct jffs_raw_inode) | |
1205 | + raw_inode.nsize | |
1206 | + JFFS_GET_PAD_BYTES(raw_inode.nsize); | |
1207 | node->fm = jffs_fmalloced(fmc, (__u32) start, | |
1208 | (__u32) (pos - start), | |
1209 | node); | |
1210 | if (!node->fm) { | |
1211 | D(printk("jffs_scan_flash(): !node->fm\n")); | |
1212 | jffs_free_node(node); | |
1213 | DJM(no_jffs_node--); | |
1214 | ||
1215 | /* Free read buffer */ | |
1216 | kfree (read_buf); | |
1217 | ||
1218 | /* Release the flash device */ | |
1219 | flash_safe_release(fmc->mtd); | |
1220 | ||
1221 | return -ENOMEM; | |
1222 | } | |
1223 | if ((err = jffs_insert_node(c, NULL, &raw_inode, | |
1224 | name, node)) < 0) { | |
1225 | printk("JFFS: Failed to handle raw inode. " | |
1226 | "(err = %d)\n", err); | |
1227 | break; | |
1228 | } | |
1229 | if (raw_inode.rename) { | |
1230 | struct jffs_delete_list *dl | |
1231 | = (struct jffs_delete_list *) | |
1232 | kmalloc(sizeof(struct jffs_delete_list), | |
1233 | GFP_KERNEL); | |
1234 | if (!dl) { | |
1235 | D(printk("jffs_scan_flash: !dl\n")); | |
1236 | jffs_free_node(node); | |
1237 | DJM(no_jffs_node--); | |
1238 | ||
1239 | /* Release the flash device */ | |
1240 | flash_safe_release(fmc->flash_part); | |
1241 | ||
1242 | /* Free read buffer */ | |
1243 | kfree (read_buf); | |
1244 | ||
1245 | return -ENOMEM; | |
1246 | } | |
1247 | dl->ino = deleted_file; | |
1248 | dl->next = c->delete_list; | |
1249 | c->delete_list = dl; | |
1250 | node->data_size = 0; | |
1251 | } | |
1252 | D3(jffs_print_node(node)); | |
1253 | node = NULL; /* Don't free the node! */ | |
1254 | } | |
1255 | else { | |
1256 | jffs_fmalloced(fmc, (__u32) start, | |
1257 | (__u32) (pos - start), NULL); | |
1258 | D3(printk("jffs_scan_flash(): Just found an obsolete " | |
1259 | "raw_inode. Continuing the scan...\n")); | |
1260 | /* Reuse this unused struct jffs_node. */ | |
1261 | } | |
1262 | } | |
1263 | ||
1264 | if (node) { | |
1265 | jffs_free_node(node); | |
1266 | DJM(no_jffs_node--); | |
1267 | } | |
1268 | jffs_build_end(fmc); | |
1269 | ||
1270 | /* Free read buffer */ | |
1271 | kfree (read_buf); | |
1272 | ||
1273 | if(!num_free_space){ | |
1274 | printk(KERN_WARNING "jffs_scan_flash(): Did not find even a single " | |
1275 | "chunk of free space. This is BAD!\n"); | |
1276 | } | |
1277 | ||
1278 | /* Return happy */ | |
1279 | D3(printk("jffs_scan_flash(): Leaving...\n")); | |
1280 | flash_safe_release(fmc->mtd); | |
1281 | ||
1282 | /* This is to trap the "free size accounting screwed error. */ | |
1283 | free_chunk_size1 = jffs_free_size1(fmc); | |
1284 | free_chunk_size2 = jffs_free_size2(fmc); | |
1285 | ||
1286 | if (free_chunk_size1 + free_chunk_size2 != fmc->free_size) { | |
1287 | ||
1288 | printk(KERN_WARNING "jffs_scan_falsh():Free size accounting screwed\n"); | |
1289 | printk(KERN_WARNING "jfffs_scan_flash():free_chunk_size1 == 0x%x, " | |
1290 | "free_chunk_size2 == 0x%x, fmc->free_size == 0x%x\n", | |
1291 | free_chunk_size1, free_chunk_size2, fmc->free_size); | |
1292 | ||
1293 | return -1; /* Do NOT mount f/s so that we can inspect what happened. | |
1294 | Mounting this screwed up f/s will screw us up anyway. | |
1295 | */ | |
1296 | } | |
1297 | ||
1298 | return 0; /* as far as we are concerned, we are happy! */ | |
1299 | } /* jffs_scan_flash() */ | |
1300 | ||
1301 | ||
1302 | /* Insert any kind of node into the file system. Take care of data | |
1303 | insertions and deletions. Also remove redundant information. The | |
1304 | memory allocated for the `name' is regarded as "given away" in the | |
1305 | caller's perspective. */ | |
1306 | int | |
1307 | jffs_insert_node(struct jffs_control *c, struct jffs_file *f, | |
1308 | const struct jffs_raw_inode *raw_inode, | |
1309 | const char *name, struct jffs_node *node) | |
1310 | { | |
1311 | int update_name = 0; | |
1312 | int insert_into_tree = 0; | |
1313 | ||
1314 | D2(printk("jffs_insert_node(): ino = %u, version = %u, " | |
1315 | "name = \"%s\", deleted = %d\n", | |
1316 | raw_inode->ino, raw_inode->version, | |
1317 | ((name && *name) ? name : ""), raw_inode->deleted)); | |
1318 | ||
1319 | /* If there doesn't exist an associated jffs_file, then | |
1320 | create, initialize and insert one into the file system. */ | |
1321 | if (!f && !(f = jffs_find_file(c, raw_inode->ino))) { | |
1322 | if (!(f = jffs_create_file(c, raw_inode))) { | |
1323 | return -ENOMEM; | |
1324 | } | |
1325 | jffs_insert_file_into_hash(f); | |
1326 | insert_into_tree = 1; | |
1327 | } | |
1328 | node->ino = raw_inode->ino; | |
1329 | node->version = raw_inode->version; | |
1330 | node->data_size = raw_inode->dsize; | |
1331 | node->fm_offset = sizeof(struct jffs_raw_inode) + raw_inode->nsize | |
1332 | + JFFS_GET_PAD_BYTES(raw_inode->nsize); | |
1333 | node->name_size = raw_inode->nsize; | |
1334 | ||
1335 | /* Now insert the node at the correct position into the file's | |
1336 | version list. */ | |
1337 | if (!f->version_head) { | |
1338 | /* This is the first node. */ | |
1339 | f->version_head = node; | |
1340 | f->version_tail = node; | |
1341 | node->version_prev = NULL; | |
1342 | node->version_next = NULL; | |
1343 | f->highest_version = node->version; | |
1344 | update_name = 1; | |
1345 | f->mode = raw_inode->mode; | |
1346 | f->uid = raw_inode->uid; | |
1347 | f->gid = raw_inode->gid; | |
1348 | f->atime = raw_inode->atime; | |
1349 | f->mtime = raw_inode->mtime; | |
1350 | f->ctime = raw_inode->ctime; | |
1351 | } | |
1352 | else if ((f->highest_version < node->version) | |
1353 | || (node->version == 0)) { | |
1354 | /* Insert at the end of the list. I.e. this node is the | |
1355 | newest one so far. */ | |
1356 | node->version_prev = f->version_tail; | |
1357 | node->version_next = NULL; | |
1358 | f->version_tail->version_next = node; | |
1359 | f->version_tail = node; | |
1360 | f->highest_version = node->version; | |
1361 | update_name = 1; | |
1362 | f->pino = raw_inode->pino; | |
1363 | f->mode = raw_inode->mode; | |
1364 | f->uid = raw_inode->uid; | |
1365 | f->gid = raw_inode->gid; | |
1366 | f->atime = raw_inode->atime; | |
1367 | f->mtime = raw_inode->mtime; | |
1368 | f->ctime = raw_inode->ctime; | |
1369 | } | |
1370 | else if (f->version_head->version > node->version) { | |
1371 | /* Insert at the bottom of the list. */ | |
1372 | node->version_prev = NULL; | |
1373 | node->version_next = f->version_head; | |
1374 | f->version_head->version_prev = node; | |
1375 | f->version_head = node; | |
1376 | if (!f->name) { | |
1377 | update_name = 1; | |
1378 | } | |
1379 | } | |
1380 | else { | |
1381 | struct jffs_node *n; | |
1382 | int newer_name = 0; | |
1383 | /* Search for the insertion position starting from | |
1384 | the tail (newest node). */ | |
1385 | for (n = f->version_tail; n; n = n->version_prev) { | |
1386 | if (n->version < node->version) { | |
1387 | node->version_prev = n; | |
1388 | node->version_next = n->version_next; | |
1389 | node->version_next->version_prev = node; | |
1390 | n->version_next = node; | |
1391 | if (!newer_name) { | |
1392 | update_name = 1; | |
1393 | } | |
1394 | break; | |
1395 | } | |
1396 | if (n->name_size) { | |
1397 | newer_name = 1; | |
1398 | } | |
1399 | } | |
1400 | } | |
1401 | ||
1402 | /* Deletion is irreversible. If any 'deleted' node is ever | |
1403 | written, the file is deleted */ | |
1404 | if (raw_inode->deleted) | |
1405 | f->deleted = raw_inode->deleted; | |
1406 | ||
1407 | /* Perhaps update the name. */ | |
1408 | if (raw_inode->nsize && update_name && name && *name && (name != f->name)) { | |
1409 | if (f->name) { | |
1410 | kfree(f->name); | |
1411 | DJM(no_name--); | |
1412 | } | |
1413 | if (!(f->name = (char *) kmalloc(raw_inode->nsize + 1, | |
1414 | GFP_KERNEL))) { | |
1415 | return -ENOMEM; | |
1416 | } | |
1417 | DJM(no_name++); | |
1418 | memcpy(f->name, name, raw_inode->nsize); | |
1419 | f->name[raw_inode->nsize] = '\0'; | |
1420 | f->nsize = raw_inode->nsize; | |
1421 | D3(printk("jffs_insert_node(): Updated the name of " | |
1422 | "the file to \"%s\".\n", name)); | |
1423 | } | |
1424 | ||
1425 | if (!c->building_fs) { | |
1426 | D3(printk("jffs_insert_node(): ---------------------------" | |
1427 | "------------------------------------------- 1\n")); | |
1428 | if (insert_into_tree) { | |
1429 | jffs_insert_file_into_tree(f); | |
1430 | } | |
1431 | /* Once upon a time, we would call jffs_possibly_delete_file() | |
1432 | here. That causes an oops if someone's still got the file | |
1433 | open, so now we only do it in jffs_delete_inode() | |
1434 | -- dwmw2 | |
1435 | */ | |
1436 | if (node->data_size || node->removed_size) { | |
1437 | jffs_update_file(f, node); | |
1438 | } | |
1439 | jffs_remove_redundant_nodes(f); | |
1440 | ||
1441 | jffs_garbage_collect_trigger(c); | |
1442 | ||
1443 | D3(printk("jffs_insert_node(): ---------------------------" | |
1444 | "------------------------------------------- 2\n")); | |
1445 | } | |
1446 | ||
1447 | return 0; | |
1448 | } /* jffs_insert_node() */ | |
1449 | ||
1450 | ||
1451 | /* Unlink a jffs_node from the version list it is in. */ | |
1452 | static inline void | |
1453 | jffs_unlink_node_from_version_list(struct jffs_file *f, | |
1454 | struct jffs_node *node) | |
1455 | { | |
1456 | if (node->version_prev) { | |
1457 | node->version_prev->version_next = node->version_next; | |
1458 | } else { | |
1459 | f->version_head = node->version_next; | |
1460 | } | |
1461 | if (node->version_next) { | |
1462 | node->version_next->version_prev = node->version_prev; | |
1463 | } else { | |
1464 | f->version_tail = node->version_prev; | |
1465 | } | |
1466 | } | |
1467 | ||
1468 | ||
1469 | /* Unlink a jffs_node from the range list it is in. */ | |
1470 | static inline void | |
1471 | jffs_unlink_node_from_range_list(struct jffs_file *f, struct jffs_node *node) | |
1472 | { | |
1473 | if (node->range_prev) { | |
1474 | node->range_prev->range_next = node->range_next; | |
1475 | } | |
1476 | else { | |
1477 | f->range_head = node->range_next; | |
1478 | } | |
1479 | if (node->range_next) { | |
1480 | node->range_next->range_prev = node->range_prev; | |
1481 | } | |
1482 | else { | |
1483 | f->range_tail = node->range_prev; | |
1484 | } | |
1485 | } | |
1486 | ||
1487 | ||
1488 | /* Function used by jffs_remove_redundant_nodes() below. This function | |
1489 | classifies what kind of information a node adds to a file. */ | |
1490 | static inline __u8 | |
1491 | jffs_classify_node(struct jffs_node *node) | |
1492 | { | |
1493 | __u8 mod_type = JFFS_MODIFY_INODE; | |
1494 | ||
1495 | if (node->name_size) { | |
1496 | mod_type |= JFFS_MODIFY_NAME; | |
1497 | } | |
1498 | if (node->data_size || node->removed_size) { | |
1499 | mod_type |= JFFS_MODIFY_DATA; | |
1500 | } | |
1501 | return mod_type; | |
1502 | } | |
1503 | ||
1504 | ||
1505 | /* Remove redundant nodes from a file. Mark the on-flash memory | |
1506 | as dirty. */ | |
1507 | static int | |
1508 | jffs_remove_redundant_nodes(struct jffs_file *f) | |
1509 | { | |
1510 | struct jffs_node *newest_node; | |
1511 | struct jffs_node *cur; | |
1512 | struct jffs_node *prev; | |
1513 | __u8 newest_type; | |
1514 | __u8 mod_type; | |
1515 | __u8 node_with_name_later = 0; | |
1516 | ||
1517 | if (!(newest_node = f->version_tail)) { | |
1518 | return 0; | |
1519 | } | |
1520 | ||
1521 | /* What does the `newest_node' modify? */ | |
1522 | newest_type = jffs_classify_node(newest_node); | |
1523 | node_with_name_later = newest_type & JFFS_MODIFY_NAME; | |
1524 | ||
1525 | D3(printk("jffs_remove_redundant_nodes(): ino: %u, name: \"%s\", " | |
1526 | "newest_type: %u\n", f->ino, (f->name ? f->name : ""), | |
1527 | newest_type)); | |
1528 | ||
1529 | /* Traverse the file's nodes and determine which of them that are | |
1530 | superfluous. Yeah, this might look very complex at first | |
1531 | glance but it is actually very simple. */ | |
1532 | for (cur = newest_node->version_prev; cur; cur = prev) { | |
1533 | prev = cur->version_prev; | |
1534 | mod_type = jffs_classify_node(cur); | |
1535 | if ((mod_type <= JFFS_MODIFY_INODE) | |
1536 | || ((newest_type & JFFS_MODIFY_NAME) | |
1537 | && (mod_type | |
1538 | <= (JFFS_MODIFY_INODE + JFFS_MODIFY_NAME))) | |
1539 | || (cur->data_size == 0 && cur->removed_size | |
1540 | && !cur->version_prev && node_with_name_later)) { | |
1541 | /* Yes, this node is redundant. Remove it. */ | |
1542 | D2(printk("jffs_remove_redundant_nodes(): " | |
1543 | "Removing node: ino: %u, version: %u, " | |
1544 | "mod_type: %u\n", cur->ino, cur->version, | |
1545 | mod_type)); | |
1546 | jffs_unlink_node_from_version_list(f, cur); | |
1547 | jffs_fmfree(f->c->fmc, cur->fm, cur); | |
1548 | jffs_free_node(cur); | |
1549 | DJM(no_jffs_node--); | |
1550 | } | |
1551 | else { | |
1552 | node_with_name_later |= (mod_type & JFFS_MODIFY_NAME); | |
1553 | } | |
1554 | } | |
1555 | ||
1556 | return 0; | |
1557 | } | |
1558 | ||
1559 | ||
1560 | /* Insert a file into the hash table. */ | |
1561 | static int | |
1562 | jffs_insert_file_into_hash(struct jffs_file *f) | |
1563 | { | |
1564 | int i = f->ino % f->c->hash_len; | |
1565 | ||
1566 | D3(printk("jffs_insert_file_into_hash(): f->ino: %u\n", f->ino)); | |
1567 | ||
1568 | list_add(&f->hash, &f->c->hash[i]); | |
1569 | return 0; | |
1570 | } | |
1571 | ||
1572 | ||
1573 | /* Insert a file into the file system tree. */ | |
1574 | int | |
1575 | jffs_insert_file_into_tree(struct jffs_file *f) | |
1576 | { | |
1577 | struct jffs_file *parent; | |
1578 | ||
1579 | D3(printk("jffs_insert_file_into_tree(): name: \"%s\"\n", | |
1580 | (f->name ? f->name : ""))); | |
1581 | ||
1582 | if (!(parent = jffs_find_file(f->c, f->pino))) { | |
1583 | if (f->pino == 0) { | |
1584 | f->c->root = f; | |
1585 | f->parent = NULL; | |
1586 | f->sibling_prev = NULL; | |
1587 | f->sibling_next = NULL; | |
1588 | return 0; | |
1589 | } | |
1590 | else { | |
1591 | D1(printk("jffs_insert_file_into_tree(): Found " | |
1592 | "inode with no parent and pino == %u\n", | |
1593 | f->pino)); | |
1594 | return -1; | |
1595 | } | |
1596 | } | |
1597 | f->parent = parent; | |
1598 | f->sibling_next = parent->children; | |
1599 | if (f->sibling_next) { | |
1600 | f->sibling_next->sibling_prev = f; | |
1601 | } | |
1602 | f->sibling_prev = NULL; | |
1603 | parent->children = f; | |
1604 | return 0; | |
1605 | } | |
1606 | ||
1607 | ||
1608 | /* Remove a file from the hash table. */ | |
1609 | static int | |
1610 | jffs_unlink_file_from_hash(struct jffs_file *f) | |
1611 | { | |
1612 | D3(printk("jffs_unlink_file_from_hash(): f: 0x%p, " | |
1613 | "ino %u\n", f, f->ino)); | |
1614 | ||
1615 | list_del(&f->hash); | |
1616 | return 0; | |
1617 | } | |
1618 | ||
1619 | ||
1620 | /* Just remove the file from the parent's children. Don't free | |
1621 | any memory. */ | |
1622 | int | |
1623 | jffs_unlink_file_from_tree(struct jffs_file *f) | |
1624 | { | |
1625 | D3(printk("jffs_unlink_file_from_tree(): ino: %d, pino: %d, name: " | |
1626 | "\"%s\"\n", f->ino, f->pino, (f->name ? f->name : ""))); | |
1627 | ||
1628 | if (f->sibling_prev) { | |
1629 | f->sibling_prev->sibling_next = f->sibling_next; | |
1630 | } | |
1631 | else if (f->parent) { | |
1632 | D3(printk("f->parent=%p\n", f->parent)); | |
1633 | f->parent->children = f->sibling_next; | |
1634 | } | |
1635 | if (f->sibling_next) { | |
1636 | f->sibling_next->sibling_prev = f->sibling_prev; | |
1637 | } | |
1638 | return 0; | |
1639 | } | |
1640 | ||
1641 | ||
1642 | /* Find a file with its inode number. */ | |
1643 | struct jffs_file * | |
1644 | jffs_find_file(struct jffs_control *c, __u32 ino) | |
1645 | { | |
1646 | struct jffs_file *f; | |
1647 | int i = ino % c->hash_len; | |
1648 | struct list_head *tmp; | |
1649 | ||
1650 | D3(printk("jffs_find_file(): ino: %u\n", ino)); | |
1651 | ||
1652 | for (tmp = c->hash[i].next; tmp != &c->hash[i]; tmp = tmp->next) { | |
1653 | f = list_entry(tmp, struct jffs_file, hash); | |
1654 | if (ino != f->ino) | |
1655 | continue; | |
1656 | D3(printk("jffs_find_file(): Found file with ino " | |
1657 | "%u. (name: \"%s\")\n", | |
1658 | ino, (f->name ? f->name : "")); | |
1659 | ); | |
1660 | return f; | |
1661 | } | |
1662 | D3(printk("jffs_find_file(): Didn't find file " | |
1663 | "with ino %u.\n", ino); | |
1664 | ); | |
1665 | return NULL; | |
1666 | } | |
1667 | ||
1668 | ||
1669 | /* Find a file in a directory. We are comparing the names. */ | |
1670 | struct jffs_file * | |
1671 | jffs_find_child(struct jffs_file *dir, const char *name, int len) | |
1672 | { | |
1673 | struct jffs_file *f; | |
1674 | ||
1675 | D3(printk("jffs_find_child()\n")); | |
1676 | ||
1677 | for (f = dir->children; f; f = f->sibling_next) { | |
1678 | if (!f->deleted && f->name | |
1679 | && !strncmp(f->name, name, len) | |
1680 | && f->name[len] == '\0') { | |
1681 | break; | |
1682 | } | |
1683 | } | |
1684 | ||
1685 | D3(if (f) { | |
1686 | printk("jffs_find_child(): Found \"%s\".\n", f->name); | |
1687 | } | |
1688 | else { | |
1689 | char *copy = (char *) kmalloc(len + 1, GFP_KERNEL); | |
1690 | if (copy) { | |
1691 | memcpy(copy, name, len); | |
1692 | copy[len] = '\0'; | |
1693 | } | |
1694 | printk("jffs_find_child(): Didn't find the file \"%s\".\n", | |
1695 | (copy ? copy : "")); | |
1696 | if (copy) { | |
1697 | kfree(copy); | |
1698 | } | |
1699 | }); | |
1700 | ||
1701 | return f; | |
1702 | } | |
1703 | ||
1704 | ||
1705 | /* Write a raw inode that takes up a certain amount of space in the flash | |
1706 | memory. At the end of the flash device, there is often space that is | |
1707 | impossible to use. At these times we want to mark this space as not | |
1708 | used. In the cases when the amount of space is greater or equal than | |
1709 | a struct jffs_raw_inode, we write a "dummy node" that takes up this | |
1710 | space. The space after the raw inode, if it exists, is left as it is. | |
1711 | Since this space after the raw inode contains JFFS_EMPTY_BITMASK bytes, | |
1712 | we can compute the checksum of it; we don't have to manipulate it any | |
1713 | further. | |
1714 | ||
1715 | If the space left on the device is less than the size of a struct | |
1716 | jffs_raw_inode, this space is filled with JFFS_DIRTY_BITMASK bytes. | |
1717 | No raw inode is written this time. */ | |
1718 | static int | |
1719 | jffs_write_dummy_node(struct jffs_control *c, struct jffs_fm *dirty_fm) | |
1720 | { | |
1721 | struct jffs_fmcontrol *fmc = c->fmc; | |
1722 | int err; | |
1723 | ||
1724 | D1(printk("jffs_write_dummy_node(): dirty_fm->offset = 0x%08x, " | |
1725 | "dirty_fm->size = %u\n", | |
1726 | dirty_fm->offset, dirty_fm->size)); | |
1727 | ||
1728 | if (dirty_fm->size >= sizeof(struct jffs_raw_inode)) { | |
1729 | struct jffs_raw_inode raw_inode; | |
1730 | memset(&raw_inode, 0, sizeof(struct jffs_raw_inode)); | |
1731 | raw_inode.magic = JFFS_MAGIC_BITMASK; | |
1732 | raw_inode.dsize = dirty_fm->size | |
1733 | - sizeof(struct jffs_raw_inode); | |
1734 | raw_inode.dchksum = raw_inode.dsize * 0xff; | |
1735 | raw_inode.chksum | |
1736 | = jffs_checksum(&raw_inode, sizeof(struct jffs_raw_inode)); | |
1737 | ||
1738 | if ((err = flash_safe_write(fmc->mtd, | |
1739 | dirty_fm->offset, | |
1740 | (u_char *)&raw_inode, | |
1741 | sizeof(struct jffs_raw_inode))) | |
1742 | < 0) { | |
1743 | printk(KERN_ERR "JFFS: jffs_write_dummy_node: " | |
1744 | "flash_safe_write failed!\n"); | |
1745 | return err; | |
1746 | } | |
1747 | } | |
1748 | else { | |
1749 | flash_safe_acquire(fmc->mtd); | |
1750 | flash_memset(fmc->mtd, dirty_fm->offset, 0, dirty_fm->size); | |
1751 | flash_safe_release(fmc->mtd); | |
1752 | } | |
1753 | ||
1754 | D3(printk("jffs_write_dummy_node(): Leaving...\n")); | |
1755 | return 0; | |
1756 | } | |
1757 | ||
1758 | ||
1759 | /* Write a raw inode, possibly its name and possibly some data. */ | |
1760 | int | |
1761 | jffs_write_node(struct jffs_control *c, struct jffs_node *node, | |
1762 | struct jffs_raw_inode *raw_inode, | |
1763 | const char *name, const unsigned char *data, | |
1764 | int recoverable, | |
1765 | struct jffs_file *f) | |
1766 | { | |
1767 | struct jffs_fmcontrol *fmc = c->fmc; | |
1768 | struct jffs_fm *fm; | |
1769 | struct kvec node_iovec[4]; | |
1770 | unsigned long iovec_cnt; | |
1771 | ||
1772 | __u32 pos; | |
1773 | int err; | |
1774 | __u32 slack = 0; | |
1775 | ||
1776 | __u32 total_name_size = raw_inode->nsize | |
1777 | + JFFS_GET_PAD_BYTES(raw_inode->nsize); | |
1778 | __u32 total_data_size = raw_inode->dsize | |
1779 | + JFFS_GET_PAD_BYTES(raw_inode->dsize); | |
1780 | __u32 total_size = sizeof(struct jffs_raw_inode) | |
1781 | + total_name_size + total_data_size; | |
1782 | ||
1783 | /* If this node isn't something that will eventually let | |
1784 | GC free even more space, then don't allow it unless | |
1785 | there's at least max_chunk_size space still available | |
1786 | */ | |
1787 | if (!recoverable) | |
1788 | slack = fmc->max_chunk_size; | |
1789 | ||
1790 | ||
1791 | /* Fire the retrorockets and shoot the fruiton torpedoes, sir! */ | |
1792 | ||
1793 | ASSERT(if (!node) { | |
1794 | printk("jffs_write_node(): node == NULL\n"); | |
1795 | return -EINVAL; | |
1796 | }); | |
1797 | ASSERT(if (raw_inode && raw_inode->nsize && !name) { | |
1798 | printk("*** jffs_write_node(): nsize = %u but name == NULL\n", | |
1799 | raw_inode->nsize); | |
1800 | return -EINVAL; | |
1801 | }); | |
1802 | ||
1803 | D1(printk("jffs_write_node(): filename = \"%s\", ino = %u, " | |
1804 | "total_size = %u\n", | |
1805 | (name ? name : ""), raw_inode->ino, | |
1806 | total_size)); | |
1807 | ||
1808 | jffs_fm_write_lock(fmc); | |
1809 | ||
1810 | retry: | |
1811 | fm = NULL; | |
1812 | err = 0; | |
1813 | while (!fm) { | |
1814 | ||
1815 | /* Deadlocks suck. */ | |
1816 | while(fmc->free_size < fmc->min_free_size + total_size + slack) { | |
1817 | jffs_fm_write_unlock(fmc); | |
1818 | if (!JFFS_ENOUGH_SPACE(c, total_size + slack)) | |
1819 | return -ENOSPC; | |
1820 | jffs_fm_write_lock(fmc); | |
1821 | } | |
1822 | ||
1823 | /* First try to allocate some flash memory. */ | |
1824 | err = jffs_fmalloc(fmc, total_size, node, &fm); | |
1825 | ||
1826 | if (err == -ENOSPC) { | |
1827 | /* Just out of space. GC and try again */ | |
1828 | if (fmc->dirty_size < fmc->sector_size) { | |
1829 | D(printk("jffs_write_node(): jffs_fmalloc(0x%p, %u) " | |
1830 | "failed, no dirty space to GC\n", fmc, | |
1831 | total_size)); | |
1832 | return err; | |
1833 | } | |
1834 | ||
1835 | D1(printk(KERN_INFO "jffs_write_node(): Calling jffs_garbage_collect_now()\n")); | |
1836 | jffs_fm_write_unlock(fmc); | |
1837 | if ((err = jffs_garbage_collect_now(c))) { | |
1838 | D(printk("jffs_write_node(): jffs_garbage_collect_now() failed\n")); | |
1839 | return err; | |
1840 | } | |
1841 | jffs_fm_write_lock(fmc); | |
1842 | continue; | |
1843 | } | |
1844 | ||
1845 | if (err < 0) { | |
1846 | jffs_fm_write_unlock(fmc); | |
1847 | ||
1848 | D(printk("jffs_write_node(): jffs_fmalloc(0x%p, %u) " | |
1849 | "failed!\n", fmc, total_size)); | |
1850 | return err; | |
1851 | } | |
1852 | ||
1853 | if (!fm->nodes) { | |
1854 | /* The jffs_fm struct that we got is not good enough. | |
1855 | Make that space dirty and try again */ | |
1856 | if ((err = jffs_write_dummy_node(c, fm)) < 0) { | |
1857 | kfree(fm); | |
1858 | DJM(no_jffs_fm--); | |
1859 | jffs_fm_write_unlock(fmc); | |
1860 | D(printk("jffs_write_node(): " | |
1861 | "jffs_write_dummy_node(): Failed!\n")); | |
1862 | return err; | |
1863 | } | |
1864 | fm = NULL; | |
1865 | } | |
1866 | } /* while(!fm) */ | |
1867 | node->fm = fm; | |
1868 | ||
1869 | ASSERT(if (fm->nodes == 0) { | |
1870 | printk(KERN_ERR "jffs_write_node(): fm->nodes == 0\n"); | |
1871 | }); | |
1872 | ||
1873 | pos = node->fm->offset; | |
1874 | ||
1875 | /* Increment the version number here. We can't let the caller | |
1876 | set it beforehand, because we might have had to do GC on a node | |
1877 | of this file - and we'd end up reusing version numbers. | |
1878 | */ | |
1879 | if (f) { | |
1880 | raw_inode->version = f->highest_version + 1; | |
1881 | D1(printk (KERN_NOTICE "jffs_write_node(): setting version of %s to %d\n", f->name, raw_inode->version)); | |
1882 | ||
1883 | /* if the file was deleted, set the deleted bit in the raw inode */ | |
1884 | if (f->deleted) | |
1885 | raw_inode->deleted = 1; | |
1886 | } | |
1887 | ||
1888 | /* Compute the checksum for the data and name chunks. */ | |
1889 | raw_inode->dchksum = jffs_checksum(data, raw_inode->dsize); | |
1890 | raw_inode->nchksum = jffs_checksum(name, raw_inode->nsize); | |
1891 | ||
1892 | /* The checksum is calculated without the chksum and accurate | |
1893 | fields so set them to zero first. */ | |
1894 | raw_inode->accurate = 0; | |
1895 | raw_inode->chksum = 0; | |
1896 | raw_inode->chksum = jffs_checksum(raw_inode, | |
1897 | sizeof(struct jffs_raw_inode)); | |
1898 | raw_inode->accurate = 0xff; | |
1899 | ||
1900 | D3(printk("jffs_write_node(): About to write this raw inode to the " | |
1901 | "flash at pos 0x%lx:\n", (long)pos)); | |
1902 | D3(jffs_print_raw_inode(raw_inode)); | |
1903 | ||
1904 | /* The actual raw JFFS node */ | |
1905 | node_iovec[0].iov_base = (void *) raw_inode; | |
1906 | node_iovec[0].iov_len = (size_t) sizeof(struct jffs_raw_inode); | |
1907 | iovec_cnt = 1; | |
1908 | ||
1909 | /* Get name and size if there is one */ | |
1910 | if (raw_inode->nsize) { | |
1911 | node_iovec[iovec_cnt].iov_base = (void *) name; | |
1912 | node_iovec[iovec_cnt].iov_len = (size_t) raw_inode->nsize; | |
1913 | iovec_cnt++; | |
1914 | ||
1915 | if (JFFS_GET_PAD_BYTES(raw_inode->nsize)) { | |
1916 | static char allff[3]={255,255,255}; | |
1917 | /* Add some extra padding if necessary */ | |
1918 | node_iovec[iovec_cnt].iov_base = allff; | |
1919 | node_iovec[iovec_cnt].iov_len = | |
1920 | JFFS_GET_PAD_BYTES(raw_inode->nsize); | |
1921 | iovec_cnt++; | |
1922 | } | |
1923 | } | |
1924 | ||
1925 | /* Get data and size if there is any */ | |
1926 | if (raw_inode->dsize) { | |
1927 | node_iovec[iovec_cnt].iov_base = (void *) data; | |
1928 | node_iovec[iovec_cnt].iov_len = (size_t) raw_inode->dsize; | |
1929 | iovec_cnt++; | |
1930 | /* No need to pad this because we're not actually putting | |
1931 | anything after it. | |
1932 | */ | |
1933 | } | |
1934 | ||
1935 | if ((err = flash_safe_writev(fmc->mtd, node_iovec, iovec_cnt, | |
1936 | pos)) < 0) { | |
1937 | jffs_fmfree_partly(fmc, fm, 0); | |
1938 | jffs_fm_write_unlock(fmc); | |
1939 | printk(KERN_ERR "JFFS: jffs_write_node: Failed to write, " | |
1940 | "requested %i, wrote %i\n", total_size, err); | |
1941 | goto retry; | |
1942 | } | |
1943 | if (raw_inode->deleted) | |
1944 | f->deleted = 1; | |
1945 | ||
1946 | jffs_fm_write_unlock(fmc); | |
1947 | D3(printk("jffs_write_node(): Leaving...\n")); | |
1948 | return raw_inode->dsize; | |
1949 | } /* jffs_write_node() */ | |
1950 | ||
1951 | ||
1952 | /* Read data from the node and write it to the buffer. 'node_offset' | |
1953 | is how much we have read from this particular node before and which | |
1954 | shouldn't be read again. 'max_size' is how much space there is in | |
1955 | the buffer. */ | |
1956 | static int | |
1957 | jffs_get_node_data(struct jffs_file *f, struct jffs_node *node, | |
1958 | unsigned char *buf,__u32 node_offset, __u32 max_size) | |
1959 | { | |
1960 | struct jffs_fmcontrol *fmc = f->c->fmc; | |
1961 | __u32 pos = node->fm->offset + node->fm_offset + node_offset; | |
1962 | __u32 avail = node->data_size - node_offset; | |
1963 | __u32 r; | |
1964 | ||
1965 | D2(printk(" jffs_get_node_data(): file: \"%s\", ino: %u, " | |
1966 | "version: %u, node_offset: %u\n", | |
1967 | f->name, node->ino, node->version, node_offset)); | |
1968 | ||
1969 | r = min(avail, max_size); | |
1970 | D3(printk(KERN_NOTICE "jffs_get_node_data\n")); | |
1971 | flash_safe_read(fmc->mtd, pos, buf, r); | |
1972 | ||
1973 | D3(printk(" jffs_get_node_data(): Read %u byte%s.\n", | |
1974 | r, (r == 1 ? "" : "s"))); | |
1975 | ||
1976 | return r; | |
1977 | } | |
1978 | ||
1979 | ||
1980 | /* Read data from the file's nodes. Write the data to the buffer | |
1981 | 'buf'. 'read_offset' tells how much data we should skip. */ | |
1982 | int | |
1983 | jffs_read_data(struct jffs_file *f, unsigned char *buf, __u32 read_offset, | |
1984 | __u32 size) | |
1985 | { | |
1986 | struct jffs_node *node; | |
1987 | __u32 read_data = 0; /* Total amount of read data. */ | |
1988 | __u32 node_offset = 0; | |
1989 | __u32 pos = 0; /* Number of bytes traversed. */ | |
1990 | ||
1991 | D2(printk("jffs_read_data(): file = \"%s\", read_offset = %d, " | |
1992 | "size = %u\n", | |
1993 | (f->name ? f->name : ""), read_offset, size)); | |
1994 | ||
1995 | if (read_offset >= f->size) { | |
1996 | D(printk(" f->size: %d\n", f->size)); | |
1997 | return 0; | |
1998 | } | |
1999 | ||
2000 | /* First find the node to read data from. */ | |
2001 | node = f->range_head; | |
2002 | while (pos <= read_offset) { | |
2003 | node_offset = read_offset - pos; | |
2004 | if (node_offset >= node->data_size) { | |
2005 | pos += node->data_size; | |
2006 | node = node->range_next; | |
2007 | } | |
2008 | else { | |
2009 | break; | |
2010 | } | |
2011 | } | |
2012 | ||
2013 | /* "Cats are living proof that not everything in nature | |
2014 | has to be useful." | |
2015 | - Garrison Keilor ('97) */ | |
2016 | ||
2017 | /* Fill the buffer. */ | |
2018 | while (node && (read_data < size)) { | |
2019 | int r; | |
2020 | if (!node->fm) { | |
2021 | /* This node does not refer to real data. */ | |
2022 | r = min(size - read_data, | |
2023 | node->data_size - node_offset); | |
2024 | memset(&buf[read_data], 0, r); | |
2025 | } | |
2026 | else if ((r = jffs_get_node_data(f, node, &buf[read_data], | |
2027 | node_offset, | |
2028 | size - read_data)) < 0) { | |
2029 | return r; | |
2030 | } | |
2031 | read_data += r; | |
2032 | node_offset = 0; | |
2033 | node = node->range_next; | |
2034 | } | |
2035 | D3(printk(" jffs_read_data(): Read %u bytes.\n", read_data)); | |
2036 | return read_data; | |
2037 | } | |
2038 | ||
2039 | ||
2040 | /* Used for traversing all nodes in the hash table. */ | |
2041 | int | |
2042 | jffs_foreach_file(struct jffs_control *c, int (*func)(struct jffs_file *)) | |
2043 | { | |
2044 | int pos; | |
2045 | int r; | |
2046 | int result = 0; | |
2047 | ||
2048 | for (pos = 0; pos < c->hash_len; pos++) { | |
2049 | struct list_head *p, *next; | |
2050 | for (p = c->hash[pos].next; p != &c->hash[pos]; p = next) { | |
2051 | /* We need a reference to the next file in the | |
2052 | list because `func' might remove the current | |
2053 | file `f'. */ | |
2054 | next = p->next; | |
2055 | r = func(list_entry(p, struct jffs_file, hash)); | |
2056 | if (r < 0) | |
2057 | return r; | |
2058 | result += r; | |
2059 | } | |
2060 | } | |
2061 | ||
2062 | return result; | |
2063 | } | |
2064 | ||
2065 | ||
2066 | /* Free all nodes associated with a file. */ | |
2067 | static int | |
2068 | jffs_free_node_list(struct jffs_file *f) | |
2069 | { | |
2070 | struct jffs_node *node; | |
2071 | struct jffs_node *p; | |
2072 | ||
2073 | D3(printk("jffs_free_node_list(): f #%u, \"%s\"\n", | |
2074 | f->ino, (f->name ? f->name : ""))); | |
2075 | node = f->version_head; | |
2076 | while (node) { | |
2077 | p = node; | |
2078 | node = node->version_next; | |
2079 | jffs_free_node(p); | |
2080 | DJM(no_jffs_node--); | |
2081 | } | |
2082 | return 0; | |
2083 | } | |
2084 | ||
2085 | ||
2086 | /* Free a file and its name. */ | |
2087 | static int | |
2088 | jffs_free_file(struct jffs_file *f) | |
2089 | { | |
2090 | D3(printk("jffs_free_file: f #%u, \"%s\"\n", | |
2091 | f->ino, (f->name ? f->name : ""))); | |
2092 | ||
2093 | if (f->name) { | |
2094 | kfree(f->name); | |
2095 | DJM(no_name--); | |
2096 | } | |
2097 | kfree(f); | |
2098 | no_jffs_file--; | |
2099 | return 0; | |
2100 | } | |
2101 | ||
2102 | static long | |
2103 | jffs_get_file_count(void) | |
2104 | { | |
2105 | return no_jffs_file; | |
2106 | } | |
2107 | ||
2108 | /* See if a file is deleted. If so, mark that file's nodes as obsolete. */ | |
2109 | int | |
2110 | jffs_possibly_delete_file(struct jffs_file *f) | |
2111 | { | |
2112 | struct jffs_node *n; | |
2113 | ||
2114 | D3(printk("jffs_possibly_delete_file(): ino: %u\n", | |
2115 | f->ino)); | |
2116 | ||
2117 | ASSERT(if (!f) { | |
2118 | printk(KERN_ERR "jffs_possibly_delete_file(): f == NULL\n"); | |
2119 | return -1; | |
2120 | }); | |
2121 | ||
2122 | if (f->deleted) { | |
2123 | /* First try to remove all older versions. Commence with | |
2124 | the oldest node. */ | |
2125 | for (n = f->version_head; n; n = n->version_next) { | |
2126 | if (!n->fm) { | |
2127 | continue; | |
2128 | } | |
2129 | if (jffs_fmfree(f->c->fmc, n->fm, n) < 0) { | |
2130 | break; | |
2131 | } | |
2132 | } | |
2133 | /* Unlink the file from the filesystem. */ | |
2134 | if (!f->c->building_fs) { | |
2135 | jffs_unlink_file_from_tree(f); | |
2136 | } | |
2137 | jffs_unlink_file_from_hash(f); | |
2138 | jffs_free_node_list(f); | |
2139 | jffs_free_file(f); | |
2140 | } | |
2141 | return 0; | |
2142 | } | |
2143 | ||
2144 | ||
2145 | /* Used in conjunction with jffs_foreach_file() to count the number | |
2146 | of files in the file system. */ | |
2147 | int | |
2148 | jffs_file_count(struct jffs_file *f) | |
2149 | { | |
2150 | return 1; | |
2151 | } | |
2152 | ||
2153 | ||
2154 | /* Build up a file's range list from scratch by going through the | |
2155 | version list. */ | |
2156 | static int | |
2157 | jffs_build_file(struct jffs_file *f) | |
2158 | { | |
2159 | struct jffs_node *n; | |
2160 | ||
2161 | D3(printk("jffs_build_file(): ino: %u, name: \"%s\"\n", | |
2162 | f->ino, (f->name ? f->name : ""))); | |
2163 | ||
2164 | for (n = f->version_head; n; n = n->version_next) { | |
2165 | jffs_update_file(f, n); | |
2166 | } | |
2167 | return 0; | |
2168 | } | |
2169 | ||
2170 | ||
2171 | /* Remove an amount of data from a file. If this amount of data is | |
2172 | zero, that could mean that a node should be split in two parts. | |
2173 | We remove or change the appropriate nodes in the lists. | |
2174 | ||
2175 | Starting offset of area to be removed is node->data_offset, | |
2176 | and the length of the area is in node->removed_size. */ | |
2177 | static int | |
2178 | jffs_delete_data(struct jffs_file *f, struct jffs_node *node) | |
2179 | { | |
2180 | struct jffs_node *n; | |
2181 | __u32 offset = node->data_offset; | |
2182 | __u32 remove_size = node->removed_size; | |
2183 | ||
2184 | D3(printk("jffs_delete_data(): offset = %u, remove_size = %u\n", | |
2185 | offset, remove_size)); | |
2186 | ||
2187 | if (remove_size == 0 | |
2188 | && f->range_tail | |
2189 | && f->range_tail->data_offset + f->range_tail->data_size | |
2190 | == offset) { | |
2191 | /* A simple append; nothing to remove or no node to split. */ | |
2192 | return 0; | |
2193 | } | |
2194 | ||
2195 | /* Find the node where we should begin the removal. */ | |
2196 | for (n = f->range_head; n; n = n->range_next) { | |
2197 | if (n->data_offset + n->data_size > offset) { | |
2198 | break; | |
2199 | } | |
2200 | } | |
2201 | if (!n) { | |
2202 | /* If there's no data in the file there's no data to | |
2203 | remove either. */ | |
2204 | return 0; | |
2205 | } | |
2206 | ||
2207 | if (n->data_offset > offset) { | |
2208 | /* XXX: Not implemented yet. */ | |
2209 | printk(KERN_WARNING "JFFS: An unexpected situation " | |
2210 | "occurred in jffs_delete_data.\n"); | |
2211 | } | |
2212 | else if (n->data_offset < offset) { | |
2213 | /* See if the node has to be split into two parts. */ | |
2214 | if (n->data_offset + n->data_size > offset + remove_size) { | |
2215 | /* Do the split. */ | |
2216 | struct jffs_node *new_node; | |
2217 | D3(printk("jffs_delete_data(): Split node with " | |
2218 | "version number %u.\n", n->version)); | |
2219 | ||
2220 | if (!(new_node = jffs_alloc_node())) { | |
2221 | D(printk("jffs_delete_data(): -ENOMEM\n")); | |
2222 | return -ENOMEM; | |
2223 | } | |
2224 | DJM(no_jffs_node++); | |
2225 | ||
2226 | new_node->ino = n->ino; | |
2227 | new_node->version = n->version; | |
2228 | new_node->data_offset = offset; | |
2229 | new_node->data_size = n->data_size - (remove_size + (offset - n->data_offset)); | |
2230 | new_node->fm_offset = n->fm_offset + (remove_size + (offset - n->data_offset)); | |
2231 | new_node->name_size = n->name_size; | |
2232 | new_node->fm = n->fm; | |
2233 | new_node->version_prev = n; | |
2234 | new_node->version_next = n->version_next; | |
2235 | if (new_node->version_next) { | |
2236 | new_node->version_next->version_prev | |
2237 | = new_node; | |
2238 | } | |
2239 | else { | |
2240 | f->version_tail = new_node; | |
2241 | } | |
2242 | n->version_next = new_node; | |
2243 | new_node->range_prev = n; | |
2244 | new_node->range_next = n->range_next; | |
2245 | if (new_node->range_next) { | |
2246 | new_node->range_next->range_prev = new_node; | |
2247 | } | |
2248 | else { | |
2249 | f->range_tail = new_node; | |
2250 | } | |
2251 | /* A very interesting can of worms. */ | |
2252 | n->range_next = new_node; | |
2253 | n->data_size = offset - n->data_offset; | |
2254 | if (new_node->fm) | |
2255 | jffs_add_node(new_node); | |
2256 | else { | |
2257 | D1(printk(KERN_WARNING "jffs_delete_data(): Splitting an empty node (file hold).\n!")); | |
2258 | D1(printk(KERN_WARNING "FIXME: Did dwmw2 do the right thing here?\n")); | |
2259 | } | |
2260 | n = new_node->range_next; | |
2261 | remove_size = 0; | |
2262 | } | |
2263 | else { | |
2264 | /* No. No need to split the node. Just remove | |
2265 | the end of the node. */ | |
2266 | int r = min(n->data_offset + n->data_size | |
2267 | - offset, remove_size); | |
2268 | n->data_size -= r; | |
2269 | remove_size -= r; | |
2270 | n = n->range_next; | |
2271 | } | |
2272 | } | |
2273 | ||
2274 | /* Remove as many nodes as necessary. */ | |
2275 | while (n && remove_size) { | |
2276 | if (n->data_size <= remove_size) { | |
2277 | struct jffs_node *p = n; | |
2278 | remove_size -= n->data_size; | |
2279 | n = n->range_next; | |
2280 | D3(printk("jffs_delete_data(): Removing node: " | |
2281 | "ino: %u, version: %u%s\n", | |
2282 | p->ino, p->version, | |
2283 | (p->fm ? "" : " (virtual)"))); | |
2284 | if (p->fm) { | |
2285 | jffs_fmfree(f->c->fmc, p->fm, p); | |
2286 | } | |
2287 | jffs_unlink_node_from_range_list(f, p); | |
2288 | jffs_unlink_node_from_version_list(f, p); | |
2289 | jffs_free_node(p); | |
2290 | DJM(no_jffs_node--); | |
2291 | } | |
2292 | else { | |
2293 | n->data_size -= remove_size; | |
2294 | n->fm_offset += remove_size; | |
2295 | n->data_offset -= (node->removed_size - remove_size); | |
2296 | n = n->range_next; | |
2297 | break; | |
2298 | } | |
2299 | } | |
2300 | ||
2301 | /* Adjust the following nodes' information about offsets etc. */ | |
2302 | while (n && node->removed_size) { | |
2303 | n->data_offset -= node->removed_size; | |
2304 | n = n->range_next; | |
2305 | } | |
2306 | ||
2307 | if (node->removed_size > (f->size - node->data_offset)) { | |
2308 | /* It's possible that the removed_size is in fact | |
2309 | * greater than the amount of data we actually thought | |
2310 | * were present in the first place - some of the nodes | |
2311 | * which this node originally obsoleted may already have | |
2312 | * been deleted from the flash by subsequent garbage | |
2313 | * collection. | |
2314 | * | |
2315 | * If this is the case, don't let f->size go negative. | |
2316 | * Bad things would happen :) | |
2317 | */ | |
2318 | f->size = node->data_offset; | |
2319 | } else { | |
2320 | f->size -= node->removed_size; | |
2321 | } | |
2322 | D3(printk("jffs_delete_data(): f->size = %d\n", f->size)); | |
2323 | return 0; | |
2324 | } /* jffs_delete_data() */ | |
2325 | ||
2326 | ||
2327 | /* Insert some data into a file. Prior to the call to this function, | |
2328 | jffs_delete_data should be called. */ | |
2329 | static int | |
2330 | jffs_insert_data(struct jffs_file *f, struct jffs_node *node) | |
2331 | { | |
2332 | D3(printk("jffs_insert_data(): node->data_offset = %u, " | |
2333 | "node->data_size = %u, f->size = %u\n", | |
2334 | node->data_offset, node->data_size, f->size)); | |
2335 | ||
2336 | /* Find the position where we should insert data. */ | |
2337 | retry: | |
2338 | if (node->data_offset == f->size) { | |
2339 | /* A simple append. This is the most common operation. */ | |
2340 | node->range_next = NULL; | |
2341 | node->range_prev = f->range_tail; | |
2342 | if (node->range_prev) { | |
2343 | node->range_prev->range_next = node; | |
2344 | } | |
2345 | f->range_tail = node; | |
2346 | f->size += node->data_size; | |
2347 | if (!f->range_head) { | |
2348 | f->range_head = node; | |
2349 | } | |
2350 | } | |
2351 | else if (node->data_offset < f->size) { | |
2352 | /* Trying to insert data into the middle of the file. This | |
2353 | means no problem because jffs_delete_data() has already | |
2354 | prepared the range list for us. */ | |
2355 | struct jffs_node *n; | |
2356 | ||
2357 | /* Find the correct place for the insertion and then insert | |
2358 | the node. */ | |
2359 | for (n = f->range_head; n; n = n->range_next) { | |
2360 | D2(printk("Cool stuff's happening!\n")); | |
2361 | ||
2362 | if (n->data_offset == node->data_offset) { | |
2363 | node->range_prev = n->range_prev; | |
2364 | if (node->range_prev) { | |
2365 | node->range_prev->range_next = node; | |
2366 | } | |
2367 | else { | |
2368 | f->range_head = node; | |
2369 | } | |
2370 | node->range_next = n; | |
2371 | n->range_prev = node; | |
2372 | break; | |
2373 | } | |
2374 | ASSERT(else if (n->data_offset + n->data_size > | |
2375 | node->data_offset) { | |
2376 | printk(KERN_ERR "jffs_insert_data(): " | |
2377 | "Couldn't find a place to insert " | |
2378 | "the data!\n"); | |
2379 | return -1; | |
2380 | }); | |
2381 | } | |
2382 | ||
2383 | /* Adjust later nodes' offsets etc. */ | |
2384 | n = node->range_next; | |
2385 | while (n) { | |
2386 | n->data_offset += node->data_size; | |
2387 | n = n->range_next; | |
2388 | } | |
2389 | f->size += node->data_size; | |
2390 | } | |
2391 | else if (node->data_offset > f->size) { | |
2392 | /* Okay. This is tricky. This means that we want to insert | |
2393 | data at a place that is beyond the limits of the file as | |
2394 | it is constructed right now. This is actually a common | |
2395 | event that for instance could occur during the mounting | |
2396 | of the file system if a large file have been truncated, | |
2397 | rewritten and then only partially garbage collected. */ | |
2398 | ||
2399 | struct jffs_node *n; | |
2400 | ||
2401 | /* We need a place holder for the data that is missing in | |
2402 | front of this insertion. This "virtual node" will not | |
2403 | be associated with any space on the flash device. */ | |
2404 | struct jffs_node *virtual_node; | |
2405 | if (!(virtual_node = jffs_alloc_node())) { | |
2406 | return -ENOMEM; | |
2407 | } | |
2408 | ||
2409 | D(printk("jffs_insert_data: Inserting a virtual node.\n")); | |
2410 | D(printk(" node->data_offset = %u\n", node->data_offset)); | |
2411 | D(printk(" f->size = %u\n", f->size)); | |
2412 | ||
2413 | virtual_node->ino = node->ino; | |
2414 | virtual_node->version = node->version; | |
2415 | virtual_node->removed_size = 0; | |
2416 | virtual_node->fm_offset = 0; | |
2417 | virtual_node->name_size = 0; | |
2418 | virtual_node->fm = NULL; /* This is a virtual data holder. */ | |
2419 | virtual_node->version_prev = NULL; | |
2420 | virtual_node->version_next = NULL; | |
2421 | virtual_node->range_next = NULL; | |
2422 | ||
2423 | /* Are there any data at all in the file yet? */ | |
2424 | if (f->range_head) { | |
2425 | virtual_node->data_offset | |
2426 | = f->range_tail->data_offset | |
2427 | + f->range_tail->data_size; | |
2428 | virtual_node->data_size | |
2429 | = node->data_offset - virtual_node->data_offset; | |
2430 | virtual_node->range_prev = f->range_tail; | |
2431 | f->range_tail->range_next = virtual_node; | |
2432 | } | |
2433 | else { | |
2434 | virtual_node->data_offset = 0; | |
2435 | virtual_node->data_size = node->data_offset; | |
2436 | virtual_node->range_prev = NULL; | |
2437 | f->range_head = virtual_node; | |
2438 | } | |
2439 | ||
2440 | f->range_tail = virtual_node; | |
2441 | f->size += virtual_node->data_size; | |
2442 | ||
2443 | /* Insert this virtual node in the version list as well. */ | |
2444 | for (n = f->version_head; n ; n = n->version_next) { | |
2445 | if (n->version == virtual_node->version) { | |
2446 | virtual_node->version_prev = n->version_prev; | |
2447 | n->version_prev = virtual_node; | |
2448 | if (virtual_node->version_prev) { | |
2449 | virtual_node->version_prev | |
2450 | ->version_next = virtual_node; | |
2451 | } | |
2452 | else { | |
2453 | f->version_head = virtual_node; | |
2454 | } | |
2455 | virtual_node->version_next = n; | |
2456 | break; | |
2457 | } | |
2458 | } | |
2459 | ||
2460 | D(jffs_print_node(virtual_node)); | |
2461 | ||
2462 | /* Make a new try to insert the node. */ | |
2463 | goto retry; | |
2464 | } | |
2465 | ||
2466 | D3(printk("jffs_insert_data(): f->size = %d\n", f->size)); | |
2467 | return 0; | |
2468 | } | |
2469 | ||
2470 | ||
2471 | /* A new node (with data) has been added to the file and now the range | |
2472 | list has to be modified. */ | |
2473 | static int | |
2474 | jffs_update_file(struct jffs_file *f, struct jffs_node *node) | |
2475 | { | |
2476 | int err; | |
2477 | ||
2478 | D3(printk("jffs_update_file(): ino: %u, version: %u\n", | |
2479 | f->ino, node->version)); | |
2480 | ||
2481 | if (node->data_size == 0) { | |
2482 | if (node->removed_size == 0) { | |
2483 | /* data_offset == X */ | |
2484 | /* data_size == 0 */ | |
2485 | /* remove_size == 0 */ | |
2486 | } | |
2487 | else { | |
2488 | /* data_offset == X */ | |
2489 | /* data_size == 0 */ | |
2490 | /* remove_size != 0 */ | |
2491 | if ((err = jffs_delete_data(f, node)) < 0) { | |
2492 | return err; | |
2493 | } | |
2494 | } | |
2495 | } | |
2496 | else { | |
2497 | /* data_offset == X */ | |
2498 | /* data_size != 0 */ | |
2499 | /* remove_size == Y */ | |
2500 | if ((err = jffs_delete_data(f, node)) < 0) { | |
2501 | return err; | |
2502 | } | |
2503 | if ((err = jffs_insert_data(f, node)) < 0) { | |
2504 | return err; | |
2505 | } | |
2506 | } | |
2507 | return 0; | |
2508 | } | |
2509 | ||
2510 | /* Print the contents of a node. */ | |
2511 | void | |
2512 | jffs_print_node(struct jffs_node *n) | |
2513 | { | |
2514 | D(printk("jffs_node: 0x%p\n", n)); | |
2515 | D(printk("{\n")); | |
2516 | D(printk(" 0x%08x, /* version */\n", n->version)); | |
2517 | D(printk(" 0x%08x, /* data_offset */\n", n->data_offset)); | |
2518 | D(printk(" 0x%08x, /* data_size */\n", n->data_size)); | |
2519 | D(printk(" 0x%08x, /* removed_size */\n", n->removed_size)); | |
2520 | D(printk(" 0x%08x, /* fm_offset */\n", n->fm_offset)); | |
2521 | D(printk(" 0x%02x, /* name_size */\n", n->name_size)); | |
2522 | D(printk(" 0x%p, /* fm, fm->offset: %u */\n", | |
2523 | n->fm, (n->fm ? n->fm->offset : 0))); | |
2524 | D(printk(" 0x%p, /* version_prev */\n", n->version_prev)); | |
2525 | D(printk(" 0x%p, /* version_next */\n", n->version_next)); | |
2526 | D(printk(" 0x%p, /* range_prev */\n", n->range_prev)); | |
2527 | D(printk(" 0x%p, /* range_next */\n", n->range_next)); | |
2528 | D(printk("}\n")); | |
2529 | } | |
2530 | ||
2531 | ||
2532 | /* Print the contents of a raw inode. */ | |
2533 | void | |
2534 | jffs_print_raw_inode(struct jffs_raw_inode *raw_inode) | |
2535 | { | |
2536 | D(printk("jffs_raw_inode: inode number: %u\n", raw_inode->ino)); | |
2537 | D(printk("{\n")); | |
2538 | D(printk(" 0x%08x, /* magic */\n", raw_inode->magic)); | |
2539 | D(printk(" 0x%08x, /* ino */\n", raw_inode->ino)); | |
2540 | D(printk(" 0x%08x, /* pino */\n", raw_inode->pino)); | |
2541 | D(printk(" 0x%08x, /* version */\n", raw_inode->version)); | |
2542 | D(printk(" 0x%08x, /* mode */\n", raw_inode->mode)); | |
2543 | D(printk(" 0x%04x, /* uid */\n", raw_inode->uid)); | |
2544 | D(printk(" 0x%04x, /* gid */\n", raw_inode->gid)); | |
2545 | D(printk(" 0x%08x, /* atime */\n", raw_inode->atime)); | |
2546 | D(printk(" 0x%08x, /* mtime */\n", raw_inode->mtime)); | |
2547 | D(printk(" 0x%08x, /* ctime */\n", raw_inode->ctime)); | |
2548 | D(printk(" 0x%08x, /* offset */\n", raw_inode->offset)); | |
2549 | D(printk(" 0x%08x, /* dsize */\n", raw_inode->dsize)); | |
2550 | D(printk(" 0x%08x, /* rsize */\n", raw_inode->rsize)); | |
2551 | D(printk(" 0x%02x, /* nsize */\n", raw_inode->nsize)); | |
2552 | D(printk(" 0x%02x, /* nlink */\n", raw_inode->nlink)); | |
2553 | D(printk(" 0x%02x, /* spare */\n", | |
2554 | raw_inode->spare)); | |
2555 | D(printk(" %u, /* rename */\n", | |
2556 | raw_inode->rename)); | |
2557 | D(printk(" %u, /* deleted */\n", | |
2558 | raw_inode->deleted)); | |
2559 | D(printk(" 0x%02x, /* accurate */\n", | |
2560 | raw_inode->accurate)); | |
2561 | D(printk(" 0x%08x, /* dchksum */\n", raw_inode->dchksum)); | |
2562 | D(printk(" 0x%04x, /* nchksum */\n", raw_inode->nchksum)); | |
2563 | D(printk(" 0x%04x, /* chksum */\n", raw_inode->chksum)); | |
2564 | D(printk("}\n")); | |
2565 | } | |
2566 | ||
2567 | ||
2568 | /* Print the contents of a file. */ | |
2569 | #if 0 | |
2570 | int | |
2571 | jffs_print_file(struct jffs_file *f) | |
2572 | { | |
2573 | D(int i); | |
2574 | D(printk("jffs_file: 0x%p\n", f)); | |
2575 | D(printk("{\n")); | |
2576 | D(printk(" 0x%08x, /* ino */\n", f->ino)); | |
2577 | D(printk(" 0x%08x, /* pino */\n", f->pino)); | |
2578 | D(printk(" 0x%08x, /* mode */\n", f->mode)); | |
2579 | D(printk(" 0x%04x, /* uid */\n", f->uid)); | |
2580 | D(printk(" 0x%04x, /* gid */\n", f->gid)); | |
2581 | D(printk(" 0x%08x, /* atime */\n", f->atime)); | |
2582 | D(printk(" 0x%08x, /* mtime */\n", f->mtime)); | |
2583 | D(printk(" 0x%08x, /* ctime */\n", f->ctime)); | |
2584 | D(printk(" 0x%02x, /* nsize */\n", f->nsize)); | |
2585 | D(printk(" 0x%02x, /* nlink */\n", f->nlink)); | |
2586 | D(printk(" 0x%02x, /* deleted */\n", f->deleted)); | |
2587 | D(printk(" \"%s\", ", (f->name ? f->name : ""))); | |
2588 | D(for (i = strlen(f->name ? f->name : ""); i < 8; ++i) { | |
2589 | printk(" "); | |
2590 | }); | |
2591 | D(printk("/* name */\n")); | |
2592 | D(printk(" 0x%08x, /* size */\n", f->size)); | |
2593 | D(printk(" 0x%08x, /* highest_version */\n", | |
2594 | f->highest_version)); | |
2595 | D(printk(" 0x%p, /* c */\n", f->c)); | |
2596 | D(printk(" 0x%p, /* parent */\n", f->parent)); | |
2597 | D(printk(" 0x%p, /* children */\n", f->children)); | |
2598 | D(printk(" 0x%p, /* sibling_prev */\n", f->sibling_prev)); | |
2599 | D(printk(" 0x%p, /* sibling_next */\n", f->sibling_next)); | |
2600 | D(printk(" 0x%p, /* hash_prev */\n", f->hash.prev)); | |
2601 | D(printk(" 0x%p, /* hash_next */\n", f->hash.next)); | |
2602 | D(printk(" 0x%p, /* range_head */\n", f->range_head)); | |
2603 | D(printk(" 0x%p, /* range_tail */\n", f->range_tail)); | |
2604 | D(printk(" 0x%p, /* version_head */\n", f->version_head)); | |
2605 | D(printk(" 0x%p, /* version_tail */\n", f->version_tail)); | |
2606 | D(printk("}\n")); | |
2607 | return 0; | |
2608 | } | |
2609 | #endif /* 0 */ | |
2610 | ||
2611 | void | |
2612 | jffs_print_hash_table(struct jffs_control *c) | |
2613 | { | |
2614 | int i; | |
2615 | ||
2616 | printk("JFFS: Dumping the file system's hash table...\n"); | |
2617 | for (i = 0; i < c->hash_len; i++) { | |
2618 | struct list_head *p; | |
2619 | for (p = c->hash[i].next; p != &c->hash[i]; p = p->next) { | |
2620 | struct jffs_file *f=list_entry(p,struct jffs_file,hash); | |
2621 | printk("*** c->hash[%u]: \"%s\" " | |
2622 | "(ino: %u, pino: %u)\n", | |
2623 | i, (f->name ? f->name : ""), | |
2624 | f->ino, f->pino); | |
2625 | } | |
2626 | } | |
2627 | } | |
2628 | ||
2629 | ||
2630 | void | |
2631 | jffs_print_tree(struct jffs_file *first_file, int indent) | |
2632 | { | |
2633 | struct jffs_file *f; | |
2634 | char *space; | |
2635 | int dir; | |
2636 | ||
2637 | if (!first_file) { | |
2638 | return; | |
2639 | } | |
2640 | ||
2641 | if (!(space = (char *) kmalloc(indent + 1, GFP_KERNEL))) { | |
2642 | printk("jffs_print_tree(): Out of memory!\n"); | |
2643 | return; | |
2644 | } | |
2645 | ||
2646 | memset(space, ' ', indent); | |
2647 | space[indent] = '\0'; | |
2648 | ||
2649 | for (f = first_file; f; f = f->sibling_next) { | |
2650 | dir = S_ISDIR(f->mode); | |
2651 | printk("%s%s%s (ino: %u, highest_version: %u, size: %u)\n", | |
2652 | space, (f->name ? f->name : ""), (dir ? "/" : ""), | |
2653 | f->ino, f->highest_version, f->size); | |
2654 | if (dir) { | |
2655 | jffs_print_tree(f->children, indent + 2); | |
2656 | } | |
2657 | } | |
2658 | ||
2659 | kfree(space); | |
2660 | } | |
2661 | ||
2662 | ||
2663 | #if defined(JFFS_MEMORY_DEBUG) && JFFS_MEMORY_DEBUG | |
2664 | void | |
2665 | jffs_print_memory_allocation_statistics(void) | |
2666 | { | |
2667 | static long printout; | |
2668 | printk("________ Memory printout #%ld ________\n", ++printout); | |
2669 | printk("no_jffs_file = %ld\n", no_jffs_file); | |
2670 | printk("no_jffs_node = %ld\n", no_jffs_node); | |
2671 | printk("no_jffs_control = %ld\n", no_jffs_control); | |
2672 | printk("no_jffs_raw_inode = %ld\n", no_jffs_raw_inode); | |
2673 | printk("no_jffs_node_ref = %ld\n", no_jffs_node_ref); | |
2674 | printk("no_jffs_fm = %ld\n", no_jffs_fm); | |
2675 | printk("no_jffs_fmcontrol = %ld\n", no_jffs_fmcontrol); | |
2676 | printk("no_hash = %ld\n", no_hash); | |
2677 | printk("no_name = %ld\n", no_name); | |
2678 | printk("\n"); | |
2679 | } | |
2680 | #endif | |
2681 | ||
2682 | ||
2683 | /* Rewrite `size' bytes, and begin at `node'. */ | |
2684 | static int | |
2685 | jffs_rewrite_data(struct jffs_file *f, struct jffs_node *node, __u32 size) | |
2686 | { | |
2687 | struct jffs_control *c = f->c; | |
2688 | struct jffs_fmcontrol *fmc = c->fmc; | |
2689 | struct jffs_raw_inode raw_inode; | |
2690 | struct jffs_node *new_node; | |
2691 | struct jffs_fm *fm; | |
2692 | __u32 pos; | |
2693 | __u32 pos_dchksum; | |
2694 | __u32 total_name_size; | |
2695 | __u32 total_data_size; | |
2696 | __u32 total_size; | |
2697 | int err; | |
2698 | ||
2699 | D1(printk("***jffs_rewrite_data(): node: %u, name: \"%s\", size: %u\n", | |
2700 | f->ino, (f->name ? f->name : "(null)"), size)); | |
2701 | ||
2702 | /* Create and initialize the new node. */ | |
2703 | if (!(new_node = jffs_alloc_node())) { | |
2704 | D(printk("jffs_rewrite_data(): " | |
2705 | "Failed to allocate node.\n")); | |
2706 | return -ENOMEM; | |
2707 | } | |
2708 | DJM(no_jffs_node++); | |
2709 | new_node->data_offset = node->data_offset; | |
2710 | new_node->removed_size = size; | |
2711 | total_name_size = JFFS_PAD(f->nsize); | |
2712 | total_data_size = JFFS_PAD(size); | |
2713 | total_size = sizeof(struct jffs_raw_inode) | |
2714 | + total_name_size + total_data_size; | |
2715 | new_node->fm_offset = sizeof(struct jffs_raw_inode) | |
2716 | + total_name_size; | |
2717 | ||
2718 | retry: | |
2719 | jffs_fm_write_lock(fmc); | |
2720 | err = 0; | |
2721 | ||
2722 | if ((err = jffs_fmalloc(fmc, total_size, new_node, &fm)) < 0) { | |
2723 | DJM(no_jffs_node--); | |
2724 | jffs_fm_write_unlock(fmc); | |
2725 | D(printk("jffs_rewrite_data(): Failed to allocate fm.\n")); | |
2726 | jffs_free_node(new_node); | |
2727 | return err; | |
2728 | } | |
2729 | else if (!fm->nodes) { | |
2730 | /* The jffs_fm struct that we got is not big enough. */ | |
2731 | /* This should never happen, because we deal with this case | |
2732 | in jffs_garbage_collect_next().*/ | |
2733 | printk(KERN_WARNING "jffs_rewrite_data(): Allocated node is too small (%d bytes of %d)\n", fm->size, total_size); | |
2734 | if ((err = jffs_write_dummy_node(c, fm)) < 0) { | |
2735 | D(printk("jffs_rewrite_data(): " | |
2736 | "jffs_write_dummy_node() Failed!\n")); | |
2737 | } else { | |
2738 | err = -ENOSPC; | |
2739 | } | |
2740 | DJM(no_jffs_fm--); | |
2741 | jffs_fm_write_unlock(fmc); | |
2742 | kfree(fm); | |
2743 | ||
2744 | return err; | |
2745 | } | |
2746 | new_node->fm = fm; | |
2747 | ||
2748 | /* Initialize the raw inode. */ | |
2749 | raw_inode.magic = JFFS_MAGIC_BITMASK; | |
2750 | raw_inode.ino = f->ino; | |
2751 | raw_inode.pino = f->pino; | |
2752 | raw_inode.version = f->highest_version + 1; | |
2753 | raw_inode.mode = f->mode; | |
2754 | raw_inode.uid = f->uid; | |
2755 | raw_inode.gid = f->gid; | |
2756 | raw_inode.atime = f->atime; | |
2757 | raw_inode.mtime = f->mtime; | |
2758 | raw_inode.ctime = f->ctime; | |
2759 | raw_inode.offset = node->data_offset; | |
2760 | raw_inode.dsize = size; | |
2761 | raw_inode.rsize = size; | |
2762 | raw_inode.nsize = f->nsize; | |
2763 | raw_inode.nlink = f->nlink; | |
2764 | raw_inode.spare = 0; | |
2765 | raw_inode.rename = 0; | |
2766 | raw_inode.deleted = f->deleted; | |
2767 | raw_inode.accurate = 0xff; | |
2768 | raw_inode.dchksum = 0; | |
2769 | raw_inode.nchksum = 0; | |
2770 | ||
2771 | pos = new_node->fm->offset; | |
2772 | pos_dchksum = pos +JFFS_RAW_INODE_DCHKSUM_OFFSET; | |
2773 | ||
2774 | D3(printk("jffs_rewrite_data(): Writing this raw inode " | |
2775 | "to pos 0x%ul.\n", pos)); | |
2776 | D3(jffs_print_raw_inode(&raw_inode)); | |
2777 | ||
2778 | if ((err = flash_safe_write(fmc->mtd, pos, | |
2779 | (u_char *) &raw_inode, | |
2780 | sizeof(struct jffs_raw_inode) | |
2781 | - sizeof(__u32) | |
2782 | - sizeof(__u16) - sizeof(__u16))) < 0) { | |
2783 | jffs_fmfree_partly(fmc, fm, | |
2784 | total_name_size + total_data_size); | |
2785 | jffs_fm_write_unlock(fmc); | |
2786 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Write error during " | |
2787 | "rewrite. (raw inode)\n"); | |
2788 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Now retrying " | |
2789 | "rewrite. (raw inode)\n"); | |
2790 | goto retry; | |
2791 | } | |
2792 | pos += sizeof(struct jffs_raw_inode); | |
2793 | ||
2794 | /* Write the name to the flash memory. */ | |
2795 | if (f->nsize) { | |
2796 | D3(printk("jffs_rewrite_data(): Writing name \"%s\" to " | |
2797 | "pos 0x%ul.\n", f->name, (unsigned int) pos)); | |
2798 | if ((err = flash_safe_write(fmc->mtd, pos, | |
2799 | (u_char *)f->name, | |
2800 | f->nsize)) < 0) { | |
2801 | jffs_fmfree_partly(fmc, fm, total_data_size); | |
2802 | jffs_fm_write_unlock(fmc); | |
2803 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Write " | |
2804 | "error during rewrite. (name)\n"); | |
2805 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Now retrying " | |
2806 | "rewrite. (name)\n"); | |
2807 | goto retry; | |
2808 | } | |
2809 | pos += total_name_size; | |
2810 | raw_inode.nchksum = jffs_checksum(f->name, f->nsize); | |
2811 | } | |
2812 | ||
2813 | /* Write the data. */ | |
2814 | if (size) { | |
2815 | int r; | |
2816 | unsigned char *page; | |
2817 | __u32 offset = node->data_offset; | |
2818 | ||
2819 | if (!(page = (unsigned char *)__get_free_page(GFP_KERNEL))) { | |
2820 | jffs_fmfree_partly(fmc, fm, 0); | |
2821 | return -1; | |
2822 | } | |
2823 | ||
2824 | while (size) { | |
2825 | __u32 s = min(size, (__u32)PAGE_SIZE); | |
2826 | if ((r = jffs_read_data(f, (char *)page, | |
2827 | offset, s)) < s) { | |
2828 | free_page((unsigned long)page); | |
2829 | jffs_fmfree_partly(fmc, fm, 0); | |
2830 | jffs_fm_write_unlock(fmc); | |
2831 | printk(KERN_ERR "JFFS: jffs_rewrite_data: " | |
2832 | "jffs_read_data() " | |
2833 | "failed! (r = %d)\n", r); | |
2834 | return -1; | |
2835 | } | |
2836 | if ((err = flash_safe_write(fmc->mtd, | |
2837 | pos, page, r)) < 0) { | |
2838 | free_page((unsigned long)page); | |
2839 | jffs_fmfree_partly(fmc, fm, 0); | |
2840 | jffs_fm_write_unlock(fmc); | |
2841 | printk(KERN_ERR "JFFS: jffs_rewrite_data: " | |
2842 | "Write error during rewrite. " | |
2843 | "(data)\n"); | |
2844 | goto retry; | |
2845 | } | |
2846 | pos += r; | |
2847 | size -= r; | |
2848 | offset += r; | |
2849 | raw_inode.dchksum += jffs_checksum(page, r); | |
2850 | } | |
2851 | ||
2852 | free_page((unsigned long)page); | |
2853 | } | |
2854 | ||
2855 | raw_inode.accurate = 0; | |
2856 | raw_inode.chksum = jffs_checksum(&raw_inode, | |
2857 | sizeof(struct jffs_raw_inode) | |
2858 | - sizeof(__u16)); | |
2859 | ||
2860 | /* Add the checksum. */ | |
2861 | if ((err | |
2862 | = flash_safe_write(fmc->mtd, pos_dchksum, | |
2863 | &((u_char *) | |
2864 | &raw_inode)[JFFS_RAW_INODE_DCHKSUM_OFFSET], | |
2865 | sizeof(__u32) + sizeof(__u16) | |
2866 | + sizeof(__u16))) < 0) { | |
2867 | jffs_fmfree_partly(fmc, fm, 0); | |
2868 | jffs_fm_write_unlock(fmc); | |
2869 | printk(KERN_ERR "JFFS: jffs_rewrite_data: Write error during " | |
2870 | "rewrite. (checksum)\n"); | |
2871 | goto retry; | |
2872 | } | |
2873 | ||
2874 | /* Now make the file system aware of the newly written node. */ | |
2875 | jffs_insert_node(c, f, &raw_inode, f->name, new_node); | |
2876 | jffs_fm_write_unlock(fmc); | |
2877 | ||
2878 | D3(printk("jffs_rewrite_data(): Leaving...\n")); | |
2879 | return 0; | |
2880 | } /* jffs_rewrite_data() */ | |
2881 | ||
2882 | ||
2883 | /* jffs_garbage_collect_next implements one step in the garbage collect | |
2884 | process and is often called multiple times at each occasion of a | |
2885 | garbage collect. */ | |
2886 | ||
2887 | static int | |
2888 | jffs_garbage_collect_next(struct jffs_control *c) | |
2889 | { | |
2890 | struct jffs_fmcontrol *fmc = c->fmc; | |
2891 | struct jffs_node *node; | |
2892 | struct jffs_file *f; | |
2893 | int err = 0; | |
2894 | __u32 size; | |
2895 | __u32 data_size; | |
2896 | __u32 total_name_size; | |
2897 | __u32 extra_available; | |
2898 | __u32 space_needed; | |
2899 | __u32 free_chunk_size1 = jffs_free_size1(fmc); | |
2900 | D2(__u32 free_chunk_size2 = jffs_free_size2(fmc)); | |
2901 | ||
2902 | /* Get the oldest node in the flash. */ | |
2903 | node = jffs_get_oldest_node(fmc); | |
2904 | ASSERT(if (!node) { | |
2905 | printk(KERN_ERR "JFFS: jffs_garbage_collect_next: " | |
2906 | "No oldest node found!\n"); | |
2907 | err = -1; | |
2908 | goto jffs_garbage_collect_next_end; | |
2909 | ||
2910 | ||
2911 | }); | |
2912 | ||
2913 | /* Find its corresponding file too. */ | |
2914 | f = jffs_find_file(c, node->ino); | |
2915 | ||
2916 | if (!f) { | |
2917 | printk (KERN_ERR "JFFS: jffs_garbage_collect_next: " | |
2918 | "No file to garbage collect! " | |
2919 | "(ino = 0x%08x)\n", node->ino); | |
2920 | /* FIXME: Free the offending node and recover. */ | |
2921 | err = -1; | |
2922 | goto jffs_garbage_collect_next_end; | |
2923 | } | |
2924 | ||
2925 | /* We always write out the name. Theoretically, we don't need | |
2926 | to, but for now it's easier - because otherwise we'd have | |
2927 | to keep track of how many times the current name exists on | |
2928 | the flash and make sure it never reaches zero. | |
2929 | ||
2930 | The current approach means that would be possible to cause | |
2931 | the GC to end up eating its tail by writing lots of nodes | |
2932 | with no name for it to garbage-collect. Hence the change in | |
2933 | inode.c to write names with _every_ node. | |
2934 | ||
2935 | It sucks, but it _should_ work. | |
2936 | */ | |
2937 | total_name_size = JFFS_PAD(f->nsize); | |
2938 | ||
2939 | D1(printk("jffs_garbage_collect_next(): \"%s\", " | |
2940 | "ino: %u, version: %u, location 0x%x, dsize %u\n", | |
2941 | (f->name ? f->name : ""), node->ino, node->version, | |
2942 | node->fm->offset, node->data_size)); | |
2943 | ||
2944 | /* Compute how many data it's possible to rewrite at the moment. */ | |
2945 | data_size = f->size - node->data_offset; | |
2946 | ||
2947 | /* And from that, the total size of the chunk we want to write */ | |
2948 | size = sizeof(struct jffs_raw_inode) + total_name_size | |
2949 | + data_size + JFFS_GET_PAD_BYTES(data_size); | |
2950 | ||
2951 | /* If that's more than max_chunk_size, reduce it accordingly */ | |
2952 | if (size > fmc->max_chunk_size) { | |
2953 | size = fmc->max_chunk_size; | |
2954 | data_size = size - sizeof(struct jffs_raw_inode) | |
2955 | - total_name_size; | |
2956 | } | |
2957 | ||
2958 | /* If we're asking to take up more space than free_chunk_size1 | |
2959 | but we _could_ fit in it, shrink accordingly. | |
2960 | */ | |
2961 | if (size > free_chunk_size1) { | |
2962 | ||
2963 | if (free_chunk_size1 < | |
2964 | (sizeof(struct jffs_raw_inode) + total_name_size + BLOCK_SIZE)){ | |
2965 | /* The space left is too small to be of any | |
2966 | use really. */ | |
2967 | struct jffs_fm *dirty_fm | |
2968 | = jffs_fmalloced(fmc, | |
2969 | fmc->tail->offset + fmc->tail->size, | |
2970 | free_chunk_size1, NULL); | |
2971 | if (!dirty_fm) { | |
2972 | printk(KERN_ERR "JFFS: " | |
2973 | "jffs_garbage_collect_next: " | |
2974 | "Failed to allocate `dirty' " | |
2975 | "flash memory!\n"); | |
2976 | err = -1; | |
2977 | goto jffs_garbage_collect_next_end; | |
2978 | } | |
2979 | D1(printk("Dirtying end of flash - too small\n")); | |
2980 | jffs_write_dummy_node(c, dirty_fm); | |
2981 | err = 0; | |
2982 | goto jffs_garbage_collect_next_end; | |
2983 | } | |
2984 | D1(printk("Reducing size of new node from %d to %d to avoid " | |
2985 | " exceeding free_chunk_size1\n", | |
2986 | size, free_chunk_size1)); | |
2987 | ||
2988 | size = free_chunk_size1; | |
2989 | data_size = size - sizeof(struct jffs_raw_inode) | |
2990 | - total_name_size; | |
2991 | } | |
2992 | ||
2993 | ||
2994 | /* Calculate the amount of space needed to hold the nodes | |
2995 | which are remaining in the tail */ | |
2996 | space_needed = fmc->min_free_size - (node->fm->offset % fmc->sector_size); | |
2997 | ||
2998 | /* From that, calculate how much 'extra' space we can use to | |
2999 | increase the size of the node we're writing from the size | |
3000 | of the node we're obsoleting | |
3001 | */ | |
3002 | if (space_needed > fmc->free_size) { | |
3003 | /* If we've gone below min_free_size for some reason, | |
3004 | don't fuck up. This is why we have | |
3005 | min_free_size > sector_size. Whinge about it though, | |
3006 | just so I can convince myself my maths is right. | |
3007 | */ | |
3008 | D1(printk(KERN_WARNING "jffs_garbage_collect_next(): " | |
3009 | "space_needed %d exceeded free_size %d\n", | |
3010 | space_needed, fmc->free_size)); | |
3011 | extra_available = 0; | |
3012 | } else { | |
3013 | extra_available = fmc->free_size - space_needed; | |
3014 | } | |
3015 | ||
3016 | /* Check that we don't use up any more 'extra' space than | |
3017 | what's available */ | |
3018 | if (size > JFFS_PAD(node->data_size) + total_name_size + | |
3019 | sizeof(struct jffs_raw_inode) + extra_available) { | |
3020 | D1(printk("Reducing size of new node from %d to %ld to avoid " | |
3021 | "catching our tail\n", size, | |
3022 | (long) (JFFS_PAD(node->data_size) + JFFS_PAD(node->name_size) + | |
3023 | sizeof(struct jffs_raw_inode) + extra_available))); | |
3024 | D1(printk("space_needed = %d, extra_available = %d\n", | |
3025 | space_needed, extra_available)); | |
3026 | ||
3027 | size = JFFS_PAD(node->data_size) + total_name_size + | |
3028 | sizeof(struct jffs_raw_inode) + extra_available; | |
3029 | data_size = size - sizeof(struct jffs_raw_inode) | |
3030 | - total_name_size; | |
3031 | }; | |
3032 | ||
3033 | D2(printk(" total_name_size: %u\n", total_name_size)); | |
3034 | D2(printk(" data_size: %u\n", data_size)); | |
3035 | D2(printk(" size: %u\n", size)); | |
3036 | D2(printk(" f->nsize: %u\n", f->nsize)); | |
3037 | D2(printk(" f->size: %u\n", f->size)); | |
3038 | D2(printk(" node->data_offset: %u\n", node->data_offset)); | |
3039 | D2(printk(" free_chunk_size1: %u\n", free_chunk_size1)); | |
3040 | D2(printk(" free_chunk_size2: %u\n", free_chunk_size2)); | |
3041 | D2(printk(" node->fm->offset: 0x%08x\n", node->fm->offset)); | |
3042 | ||
3043 | if ((err = jffs_rewrite_data(f, node, data_size))) { | |
3044 | printk(KERN_WARNING "jffs_rewrite_data() failed: %d\n", err); | |
3045 | return err; | |
3046 | } | |
3047 | ||
3048 | jffs_garbage_collect_next_end: | |
3049 | D3(printk("jffs_garbage_collect_next: Leaving...\n")); | |
3050 | return err; | |
3051 | } /* jffs_garbage_collect_next */ | |
3052 | ||
3053 | ||
3054 | /* If an obsolete node is partly going to be erased due to garbage | |
3055 | collection, the part that isn't going to be erased must be filled | |
3056 | with zeroes so that the scan of the flash will work smoothly next | |
3057 | time. (The data in the file could for instance be a JFFS image | |
3058 | which could cause enormous confusion during a scan of the flash | |
3059 | device if we didn't do this.) | |
3060 | There are two phases in this procedure: First, the clearing of | |
3061 | the name and data parts of the node. Second, possibly also clearing | |
3062 | a part of the raw inode as well. If the box is power cycled during | |
3063 | the first phase, only the checksum of this node-to-be-cleared-at- | |
3064 | the-end will be wrong. If the box is power cycled during, or after, | |
3065 | the clearing of the raw inode, the information like the length of | |
3066 | the name and data parts are zeroed. The next time the box is | |
3067 | powered up, the scanning algorithm manages this faulty data too | |
3068 | because: | |
3069 | ||
3070 | - The checksum is invalid and thus the raw inode must be discarded | |
3071 | in any case. | |
3072 | - If the lengths of the data part or the name part are zeroed, the | |
3073 | scanning just continues after the raw inode. But after the inode | |
3074 | the scanning procedure just finds zeroes which is the same as | |
3075 | dirt. | |
3076 | ||
3077 | So, in the end, this could never fail. :-) Even if it does fail, | |
3078 | the scanning algorithm should manage that too. */ | |
3079 | ||
3080 | static int | |
3081 | jffs_clear_end_of_node(struct jffs_control *c, __u32 erase_size) | |
3082 | { | |
3083 | struct jffs_fm *fm; | |
3084 | struct jffs_fmcontrol *fmc = c->fmc; | |
3085 | __u32 zero_offset; | |
3086 | __u32 zero_size; | |
3087 | __u32 zero_offset_data; | |
3088 | __u32 zero_size_data; | |
3089 | __u32 cutting_raw_inode = 0; | |
3090 | ||
3091 | if (!(fm = jffs_cut_node(fmc, erase_size))) { | |
3092 | D3(printk("jffs_clear_end_of_node(): fm == NULL\n")); | |
3093 | return 0; | |
3094 | } | |
3095 | ||
3096 | /* Where and how much shall we clear? */ | |
3097 | zero_offset = fmc->head->offset + erase_size; | |
3098 | zero_size = fm->offset + fm->size - zero_offset; | |
3099 | ||
3100 | /* Do we have to clear the raw_inode explicitly? */ | |
3101 | if (fm->size - zero_size < sizeof(struct jffs_raw_inode)) { | |
3102 | cutting_raw_inode = sizeof(struct jffs_raw_inode) | |
3103 | - (fm->size - zero_size); | |
3104 | } | |
3105 | ||
3106 | /* First, clear the name and data fields. */ | |
3107 | zero_offset_data = zero_offset + cutting_raw_inode; | |
3108 | zero_size_data = zero_size - cutting_raw_inode; | |
3109 | flash_safe_acquire(fmc->mtd); | |
3110 | flash_memset(fmc->mtd, zero_offset_data, 0, zero_size_data); | |
3111 | flash_safe_release(fmc->mtd); | |
3112 | ||
3113 | /* Should we clear a part of the raw inode? */ | |
3114 | if (cutting_raw_inode) { | |
3115 | /* I guess it is ok to clear the raw inode in this order. */ | |
3116 | flash_safe_acquire(fmc->mtd); | |
3117 | flash_memset(fmc->mtd, zero_offset, 0, | |
3118 | cutting_raw_inode); | |
3119 | flash_safe_release(fmc->mtd); | |
3120 | } | |
3121 | ||
3122 | return 0; | |
3123 | } /* jffs_clear_end_of_node() */ | |
3124 | ||
3125 | /* Try to erase as much as possible of the dirt in the flash memory. */ | |
3126 | static long | |
3127 | jffs_try_to_erase(struct jffs_control *c) | |
3128 | { | |
3129 | struct jffs_fmcontrol *fmc = c->fmc; | |
3130 | long erase_size; | |
3131 | int err; | |
3132 | __u32 offset; | |
3133 | ||
3134 | D3(printk("jffs_try_to_erase()\n")); | |
3135 | ||
3136 | erase_size = jffs_erasable_size(fmc); | |
3137 | ||
3138 | D2(printk("jffs_try_to_erase(): erase_size = %ld\n", erase_size)); | |
3139 | ||
3140 | if (erase_size == 0) { | |
3141 | return 0; | |
3142 | } | |
3143 | else if (erase_size < 0) { | |
3144 | printk(KERN_ERR "JFFS: jffs_try_to_erase: " | |
3145 | "jffs_erasable_size returned %ld.\n", erase_size); | |
3146 | return erase_size; | |
3147 | } | |
3148 | ||
3149 | if ((err = jffs_clear_end_of_node(c, erase_size)) < 0) { | |
3150 | printk(KERN_ERR "JFFS: jffs_try_to_erase: " | |
3151 | "Clearing of node failed.\n"); | |
3152 | return err; | |
3153 | } | |
3154 | ||
3155 | offset = fmc->head->offset; | |
3156 | ||
3157 | /* Now, let's try to do the erase. */ | |
3158 | if ((err = flash_erase_region(fmc->mtd, | |
3159 | offset, erase_size)) < 0) { | |
3160 | printk(KERN_ERR "JFFS: Erase of flash failed. " | |
3161 | "offset = %u, erase_size = %ld\n", | |
3162 | offset, erase_size); | |
3163 | /* XXX: Here we should allocate this area as dirty | |
3164 | with jffs_fmalloced or something similar. Now | |
3165 | we just report the error. */ | |
3166 | return err; | |
3167 | } | |
3168 | ||
3169 | #if 0 | |
3170 | /* Check if the erased sectors really got erased. */ | |
3171 | { | |
3172 | __u32 pos; | |
3173 | __u32 end; | |
3174 | ||
3175 | pos = (__u32)flash_get_direct_pointer(to_kdev_t(c->sb->s_dev), offset); | |
3176 | end = pos + erase_size; | |
3177 | ||
3178 | D2(printk("JFFS: Checking erased sector(s)...\n")); | |
3179 | ||
3180 | flash_safe_acquire(fmc->mtd); | |
3181 | ||
3182 | for (; pos < end; pos += 4) { | |
3183 | if (*(__u32 *)pos != JFFS_EMPTY_BITMASK) { | |
3184 | printk("JFFS: Erase failed! pos = 0x%lx\n", | |
3185 | (long)pos); | |
3186 | jffs_hexdump(fmc->mtd, pos, | |
3187 | jffs_min(256, end - pos)); | |
3188 | err = -1; | |
3189 | break; | |
3190 | } | |
3191 | } | |
3192 | ||
3193 | flash_safe_release(fmc->mtd); | |
3194 | ||
3195 | if (!err) { | |
3196 | D2(printk("JFFS: Erase succeeded.\n")); | |
3197 | } | |
3198 | else { | |
3199 | /* XXX: Here we should allocate the memory | |
3200 | with jffs_fmalloced() in order to prevent | |
3201 | JFFS from using this area accidentally. */ | |
3202 | return err; | |
3203 | } | |
3204 | } | |
3205 | #endif | |
3206 | ||
3207 | /* Update the flash memory data structures. */ | |
3208 | jffs_sync_erase(fmc, erase_size); | |
3209 | ||
3210 | return erase_size; | |
3211 | } | |
3212 | ||
3213 | ||
3214 | /* There are different criteria that should trigger a garbage collect: | |
3215 | ||
3216 | 1. There is too much dirt in the memory. | |
3217 | 2. The free space is becoming small. | |
3218 | 3. There are many versions of a node. | |
3219 | ||
3220 | The garbage collect should always be done in a manner that guarantees | |
3221 | that future garbage collects cannot be locked. E.g. Rewritten chunks | |
3222 | should not be too large (span more than one sector in the flash memory | |
3223 | for exemple). Of course there is a limit on how intelligent this garbage | |
3224 | collection can be. */ | |
3225 | ||
3226 | ||
3227 | static int | |
3228 | jffs_garbage_collect_now(struct jffs_control *c) | |
3229 | { | |
3230 | struct jffs_fmcontrol *fmc = c->fmc; | |
3231 | long erased = 0; | |
3232 | int result = 0; | |
3233 | D1(int i = 1); | |
3234 | D2(printk("***jffs_garbage_collect_now(): fmc->dirty_size = %u, fmc->free_size = 0x%x\n, fcs1=0x%x, fcs2=0x%x", | |
3235 | fmc->dirty_size, fmc->free_size, jffs_free_size1(fmc), jffs_free_size2(fmc))); | |
3236 | D2(jffs_print_fmcontrol(fmc)); | |
3237 | ||
3238 | // down(&fmc->gclock); | |
3239 | ||
3240 | /* If it is possible to garbage collect, do so. */ | |
3241 | ||
3242 | while (erased == 0) { | |
3243 | D1(printk("***jffs_garbage_collect_now(): round #%u, " | |
3244 | "fmc->dirty_size = %u\n", i++, fmc->dirty_size)); | |
3245 | D2(jffs_print_fmcontrol(fmc)); | |
3246 | ||
3247 | if ((erased = jffs_try_to_erase(c)) < 0) { | |
3248 | printk(KERN_WARNING "JFFS: Error in " | |
3249 | "garbage collector.\n"); | |
3250 | result = erased; | |
3251 | goto gc_end; | |
3252 | } | |
3253 | if (erased) | |
3254 | break; | |
3255 | ||
3256 | if (fmc->free_size == 0) { | |
3257 | /* Argh */ | |
3258 | printk(KERN_ERR "jffs_garbage_collect_now(): free_size == 0. This is BAD.\n"); | |
3259 | result = -ENOSPC; | |
3260 | break; | |
3261 | } | |
3262 | ||
3263 | if (fmc->dirty_size < fmc->sector_size) { | |
3264 | /* Actually, we _may_ have been able to free some, | |
3265 | * if there are many overlapping nodes which aren't | |
3266 | * actually marked dirty because they still have | |
3267 | * some valid data in each. | |
3268 | */ | |
3269 | result = -ENOSPC; | |
3270 | break; | |
3271 | } | |
3272 | ||
3273 | /* Let's dare to make a garbage collect. */ | |
3274 | if ((result = jffs_garbage_collect_next(c)) < 0) { | |
3275 | printk(KERN_ERR "JFFS: Something " | |
3276 | "has gone seriously wrong " | |
3277 | "with a garbage collect.\n"); | |
3278 | goto gc_end; | |
3279 | } | |
3280 | ||
3281 | D1(printk(" jffs_garbage_collect_now(): erased: %ld\n", erased)); | |
3282 | DJM(jffs_print_memory_allocation_statistics()); | |
3283 | } | |
3284 | ||
3285 | gc_end: | |
3286 | // up(&fmc->gclock); | |
3287 | ||
3288 | D3(printk(" jffs_garbage_collect_now(): Leaving...\n")); | |
3289 | D1(if (erased) { | |
3290 | printk("jffs_g_c_now(): erased = %ld\n", erased); | |
3291 | jffs_print_fmcontrol(fmc); | |
3292 | }); | |
3293 | ||
3294 | if (!erased && !result) | |
3295 | return -ENOSPC; | |
3296 | ||
3297 | return result; | |
3298 | } /* jffs_garbage_collect_now() */ | |
3299 | ||
3300 | ||
3301 | /* Determine if it is reasonable to start garbage collection. | |
3302 | We start a gc pass if either: | |
3303 | - The number of free bytes < MIN_FREE_BYTES && at least one | |
3304 | block is dirty, OR | |
3305 | - The number of dirty bytes > MAX_DIRTY_BYTES | |
3306 | */ | |
3307 | static inline int thread_should_wake (struct jffs_control *c) | |
3308 | { | |
3309 | D1(printk (KERN_NOTICE "thread_should_wake(): free=%d, dirty=%d, blocksize=%d.\n", | |
3310 | c->fmc->free_size, c->fmc->dirty_size, c->fmc->sector_size)); | |
3311 | ||
3312 | /* If there's not enough dirty space to free a block, there's no point. */ | |
3313 | if (c->fmc->dirty_size < c->fmc->sector_size) { | |
3314 | D2(printk(KERN_NOTICE "thread_should_wake(): Not waking. Insufficient dirty space\n")); | |
3315 | return 0; | |
3316 | } | |
3317 | #if 1 | |
3318 | /* If there is too much RAM used by the various structures, GC */ | |
3319 | if (jffs_get_node_inuse() > (c->fmc->used_size/c->fmc->max_chunk_size * 5 + jffs_get_file_count() * 2 + 50)) { | |
3320 | /* FIXME: Provide proof that this test can be satisfied. We | |
3321 | don't want a filesystem doing endless GC just because this | |
3322 | condition cannot ever be false. | |
3323 | */ | |
3324 | D2(printk(KERN_NOTICE "thread_should_wake(): Waking due to number of nodes\n")); | |
3325 | return 1; | |
3326 | } | |
3327 | #endif | |
3328 | /* If there are fewer free bytes than the threshold, GC */ | |
3329 | if (c->fmc->free_size < c->gc_minfree_threshold) { | |
3330 | D2(printk(KERN_NOTICE "thread_should_wake(): Waking due to insufficent free space\n")); | |
3331 | return 1; | |
3332 | } | |
3333 | /* If there are more dirty bytes than the threshold, GC */ | |
3334 | if (c->fmc->dirty_size > c->gc_maxdirty_threshold) { | |
3335 | D2(printk(KERN_NOTICE "thread_should_wake(): Waking due to excessive dirty space\n")); | |
3336 | return 1; | |
3337 | } | |
3338 | /* FIXME: What about the "There are many versions of a node" condition? */ | |
3339 | ||
3340 | return 0; | |
3341 | } | |
3342 | ||
3343 | ||
3344 | void jffs_garbage_collect_trigger(struct jffs_control *c) | |
3345 | { | |
3346 | /* NOTE: We rely on the fact that we have the BKL here. | |
3347 | * Otherwise, the gc_task could go away between the check | |
3348 | * and the wake_up_process() | |
3349 | */ | |
3350 | if (c->gc_task && thread_should_wake(c)) | |
3351 | send_sig(SIGHUP, c->gc_task, 1); | |
3352 | } | |
3353 | ||
3354 | ||
3355 | /* Kernel threads take (void *) as arguments. Thus we pass | |
3356 | the jffs_control data as a (void *) and then cast it. */ | |
3357 | int | |
3358 | jffs_garbage_collect_thread(void *ptr) | |
3359 | { | |
3360 | struct jffs_control *c = (struct jffs_control *) ptr; | |
3361 | struct jffs_fmcontrol *fmc = c->fmc; | |
3362 | long erased; | |
3363 | int result = 0; | |
3364 | D1(int i = 1); | |
3365 | ||
3366 | daemonize("jffs_gcd"); | |
3367 | ||
3368 | c->gc_task = current; | |
3369 | ||
3370 | lock_kernel(); | |
3371 | init_completion(&c->gc_thread_comp); /* barrier */ | |
3372 | spin_lock_irq(¤t->sighand->siglock); | |
3373 | siginitsetinv (¤t->blocked, sigmask(SIGHUP) | sigmask(SIGKILL) | sigmask(SIGSTOP) | sigmask(SIGCONT)); | |
3374 | recalc_sigpending(); | |
3375 | spin_unlock_irq(¤t->sighand->siglock); | |
3376 | ||
3377 | D1(printk (KERN_NOTICE "jffs_garbage_collect_thread(): Starting infinite loop.\n")); | |
3378 | ||
3379 | for (;;) { | |
3380 | ||
3381 | /* See if we need to start gc. If we don't, go to sleep. | |
3382 | ||
3383 | Current implementation is a BAD THING(tm). If we try | |
3384 | to unmount the FS, the unmount operation will sleep waiting | |
3385 | for this thread to exit. We need to arrange to send it a | |
3386 | sig before the umount process sleeps. | |
3387 | */ | |
3388 | ||
3389 | if (!thread_should_wake(c)) | |
3390 | set_current_state (TASK_INTERRUPTIBLE); | |
3391 | ||
3392 | schedule(); /* Yes, we do this even if we want to go | |
3393 | on immediately - we're a low priority | |
3394 | background task. */ | |
3395 | ||
3396 | /* Put_super will send a SIGKILL and then wait on the sem. | |
3397 | */ | |
3398 | while (signal_pending(current)) { | |
3399 | siginfo_t info; | |
3400 | unsigned long signr = 0; | |
3401 | ||
3402 | spin_lock_irq(¤t->sighand->siglock); | |
3403 | signr = dequeue_signal(current, ¤t->blocked, &info); | |
3404 | spin_unlock_irq(¤t->sighand->siglock); | |
3405 | ||
3406 | switch(signr) { | |
3407 | case SIGSTOP: | |
3408 | D1(printk("jffs_garbage_collect_thread(): SIGSTOP received.\n")); | |
3409 | set_current_state(TASK_STOPPED); | |
3410 | schedule(); | |
3411 | break; | |
3412 | ||
3413 | case SIGKILL: | |
3414 | D1(printk("jffs_garbage_collect_thread(): SIGKILL received.\n")); | |
3415 | c->gc_task = NULL; | |
3416 | complete_and_exit(&c->gc_thread_comp, 0); | |
3417 | } | |
3418 | } | |
3419 | ||
3420 | ||
3421 | D1(printk (KERN_NOTICE "jffs_garbage_collect_thread(): collecting.\n")); | |
3422 | ||
3423 | D3(printk (KERN_NOTICE "g_c_thread(): down biglock\n")); | |
3424 | down(&fmc->biglock); | |
3425 | ||
3426 | D1(printk("***jffs_garbage_collect_thread(): round #%u, " | |
3427 | "fmc->dirty_size = %u\n", i++, fmc->dirty_size)); | |
3428 | D2(jffs_print_fmcontrol(fmc)); | |
3429 | ||
3430 | if ((erased = jffs_try_to_erase(c)) < 0) { | |
3431 | printk(KERN_WARNING "JFFS: Error in " | |
3432 | "garbage collector: %ld.\n", erased); | |
3433 | } | |
3434 | ||
3435 | if (erased) | |
3436 | goto gc_end; | |
3437 | ||
3438 | if (fmc->free_size == 0) { | |
3439 | /* Argh. Might as well commit suicide. */ | |
3440 | printk(KERN_ERR "jffs_garbage_collect_thread(): free_size == 0. This is BAD.\n"); | |
3441 | send_sig(SIGQUIT, c->gc_task, 1); | |
3442 | // panic() | |
3443 | goto gc_end; | |
3444 | } | |
3445 | ||
3446 | /* Let's dare to make a garbage collect. */ | |
3447 | if ((result = jffs_garbage_collect_next(c)) < 0) { | |
3448 | printk(KERN_ERR "JFFS: Something " | |
3449 | "has gone seriously wrong " | |
3450 | "with a garbage collect: %d\n", result); | |
3451 | } | |
3452 | ||
3453 | gc_end: | |
3454 | D3(printk (KERN_NOTICE "g_c_thread(): up biglock\n")); | |
3455 | up(&fmc->biglock); | |
3456 | } /* for (;;) */ | |
3457 | } /* jffs_garbage_collect_thread() */ |