1 | /* |
2 | * JFFS2 -- Journalling Flash File System, Version 2. |
3 | * |
4 | * Copyright © 2001-2007 Red Hat, Inc. |
5 | * |
6 | * Created by David Woodhouse <dwmw2@infradead.org> |
7 | * |
8 | * For licensing information, see the file 'LICENCE' in this directory. |
9 | * |
10 | */ |
11 | |
12 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
13 | |
14 | #include <linux/kernel.h> |
15 | #include <linux/sched.h> |
16 | #include <linux/slab.h> |
17 | #include <linux/fs.h> |
18 | #include <linux/crc32.h> |
19 | #include <linux/pagemap.h> |
20 | #include <linux/mtd/mtd.h> |
21 | #include <linux/compiler.h> |
22 | #include "nodelist.h" |
23 | |
24 | /* |
25 | * Check the data CRC of the node. |
26 | * |
27 | * Returns: 0 if the data CRC is correct; |
28 | * 1 - if incorrect; |
29 | * error code if an error occurred. |
30 | */ |
31 | static int check_node_data(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn) |
32 | { |
33 | struct jffs2_raw_node_ref *ref = tn->fn->raw; |
34 | int err = 0, pointed = 0; |
35 | struct jffs2_eraseblock *jeb; |
36 | unsigned char *buffer; |
37 | uint32_t crc, ofs, len; |
38 | size_t retlen; |
39 | |
40 | BUG_ON(tn->csize == 0); |
41 | |
42 | /* Calculate how many bytes were already checked */ |
43 | ofs = ref_offset(ref) + sizeof(struct jffs2_raw_inode); |
44 | len = tn->csize; |
45 | |
46 | if (jffs2_is_writebuffered(c)) { |
47 | int adj = ofs % c->wbuf_pagesize; |
48 | if (likely(adj)) |
49 | adj = c->wbuf_pagesize - adj; |
50 | |
51 | if (adj >= tn->csize) { |
52 | dbg_readinode("no need to check node at %#08x, data length %u, data starts at %#08x - it has already been checked.\n" , |
53 | ref_offset(ref), tn->csize, ofs); |
54 | goto adj_acc; |
55 | } |
56 | |
57 | ofs += adj; |
58 | len -= adj; |
59 | } |
60 | |
61 | dbg_readinode("check node at %#08x, data length %u, partial CRC %#08x, correct CRC %#08x, data starts at %#08x, start checking from %#08x - %u bytes.\n" , |
62 | ref_offset(ref), tn->csize, tn->partial_crc, tn->data_crc, ofs - len, ofs, len); |
63 | |
64 | #ifndef __ECOS |
65 | /* TODO: instead, incapsulate point() stuff to jffs2_flash_read(), |
66 | * adding and jffs2_flash_read_end() interface. */ |
67 | err = mtd_point(mtd: c->mtd, from: ofs, len, retlen: &retlen, virt: (void **)&buffer, NULL); |
68 | if (!err && retlen < len) { |
69 | JFFS2_WARNING("MTD point returned len too short: %zu instead of %u.\n" , retlen, tn->csize); |
70 | mtd_unpoint(mtd: c->mtd, from: ofs, len: retlen); |
71 | } else if (err) { |
72 | if (err != -EOPNOTSUPP) |
73 | JFFS2_WARNING("MTD point failed: error code %d.\n" , err); |
74 | } else |
75 | pointed = 1; /* succefully pointed to device */ |
76 | #endif |
77 | |
78 | if (!pointed) { |
79 | buffer = kmalloc(size: len, GFP_KERNEL); |
80 | if (unlikely(!buffer)) |
81 | return -ENOMEM; |
82 | |
83 | /* TODO: this is very frequent pattern, make it a separate |
84 | * routine */ |
85 | err = jffs2_flash_read(c, ofs, len, retlen: &retlen, buf: buffer); |
86 | if (err) { |
87 | JFFS2_ERROR("can not read %d bytes from 0x%08x, error code: %d.\n" , len, ofs, err); |
88 | goto free_out; |
89 | } |
90 | |
91 | if (retlen != len) { |
92 | JFFS2_ERROR("short read at %#08x: %zd instead of %d.\n" , ofs, retlen, len); |
93 | err = -EIO; |
94 | goto free_out; |
95 | } |
96 | } |
97 | |
98 | /* Continue calculating CRC */ |
99 | crc = crc32(tn->partial_crc, buffer, len); |
100 | if(!pointed) |
101 | kfree(objp: buffer); |
102 | #ifndef __ECOS |
103 | else |
104 | mtd_unpoint(mtd: c->mtd, from: ofs, len); |
105 | #endif |
106 | |
107 | if (crc != tn->data_crc) { |
108 | JFFS2_NOTICE("wrong data CRC in data node at 0x%08x: read %#08x, calculated %#08x.\n" , |
109 | ref_offset(ref), tn->data_crc, crc); |
110 | return 1; |
111 | } |
112 | |
113 | adj_acc: |
114 | jeb = &c->blocks[ref->flash_offset / c->sector_size]; |
115 | len = ref_totlen(c, jeb, ref); |
116 | /* If it should be REF_NORMAL, it'll get marked as such when |
117 | we build the fragtree, shortly. No need to worry about GC |
118 | moving it while it's marked REF_PRISTINE -- GC won't happen |
119 | till we've finished checking every inode anyway. */ |
120 | ref->flash_offset |= REF_PRISTINE; |
121 | /* |
122 | * Mark the node as having been checked and fix the |
123 | * accounting accordingly. |
124 | */ |
125 | spin_lock(lock: &c->erase_completion_lock); |
126 | jeb->used_size += len; |
127 | jeb->unchecked_size -= len; |
128 | c->used_size += len; |
129 | c->unchecked_size -= len; |
130 | jffs2_dbg_acct_paranoia_check_nolock(c, jeb); |
131 | spin_unlock(lock: &c->erase_completion_lock); |
132 | |
133 | return 0; |
134 | |
135 | free_out: |
136 | if(!pointed) |
137 | kfree(objp: buffer); |
138 | #ifndef __ECOS |
139 | else |
140 | mtd_unpoint(mtd: c->mtd, from: ofs, len); |
141 | #endif |
142 | return err; |
143 | } |
144 | |
145 | /* |
146 | * Helper function for jffs2_add_older_frag_to_fragtree(). |
147 | * |
148 | * Checks the node if we are in the checking stage. |
149 | */ |
150 | static int check_tn_node(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn) |
151 | { |
152 | int ret; |
153 | |
154 | BUG_ON(ref_obsolete(tn->fn->raw)); |
155 | |
156 | /* We only check the data CRC of unchecked nodes */ |
157 | if (ref_flags(tn->fn->raw) != REF_UNCHECKED) |
158 | return 0; |
159 | |
160 | dbg_readinode("check node %#04x-%#04x, phys offs %#08x\n" , |
161 | tn->fn->ofs, tn->fn->ofs + tn->fn->size, ref_offset(tn->fn->raw)); |
162 | |
163 | ret = check_node_data(c, tn); |
164 | if (unlikely(ret < 0)) { |
165 | JFFS2_ERROR("check_node_data() returned error: %d.\n" , |
166 | ret); |
167 | } else if (unlikely(ret > 0)) { |
168 | dbg_readinode("CRC error, mark it obsolete.\n" ); |
169 | jffs2_mark_node_obsolete(c, raw: tn->fn->raw); |
170 | } |
171 | |
172 | return ret; |
173 | } |
174 | |
175 | static struct jffs2_tmp_dnode_info *jffs2_lookup_tn(struct rb_root *tn_root, uint32_t offset) |
176 | { |
177 | struct rb_node *next; |
178 | struct jffs2_tmp_dnode_info *tn = NULL; |
179 | |
180 | dbg_readinode("root %p, offset %d\n" , tn_root, offset); |
181 | |
182 | next = tn_root->rb_node; |
183 | |
184 | while (next) { |
185 | tn = rb_entry(next, struct jffs2_tmp_dnode_info, rb); |
186 | |
187 | if (tn->fn->ofs < offset) |
188 | next = tn->rb.rb_right; |
189 | else if (tn->fn->ofs >= offset) |
190 | next = tn->rb.rb_left; |
191 | else |
192 | break; |
193 | } |
194 | |
195 | return tn; |
196 | } |
197 | |
198 | |
199 | static void jffs2_kill_tn(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn) |
200 | { |
201 | jffs2_mark_node_obsolete(c, raw: tn->fn->raw); |
202 | jffs2_free_full_dnode(tn->fn); |
203 | jffs2_free_tmp_dnode_info(tn); |
204 | } |
205 | /* |
206 | * This function is used when we read an inode. Data nodes arrive in |
207 | * arbitrary order -- they may be older or newer than the nodes which |
208 | * are already in the tree. Where overlaps occur, the older node can |
209 | * be discarded as long as the newer passes the CRC check. We don't |
210 | * bother to keep track of holes in this rbtree, and neither do we deal |
211 | * with frags -- we can have multiple entries starting at the same |
212 | * offset, and the one with the smallest length will come first in the |
213 | * ordering. |
214 | * |
215 | * Returns 0 if the node was handled (including marking it obsolete) |
216 | * < 0 an if error occurred |
217 | */ |
218 | static int jffs2_add_tn_to_tree(struct jffs2_sb_info *c, |
219 | struct jffs2_readinode_info *rii, |
220 | struct jffs2_tmp_dnode_info *tn) |
221 | { |
222 | uint32_t fn_end = tn->fn->ofs + tn->fn->size; |
223 | struct jffs2_tmp_dnode_info *this, *ptn; |
224 | |
225 | dbg_readinode("insert fragment %#04x-%#04x, ver %u at %08x\n" , tn->fn->ofs, fn_end, tn->version, ref_offset(tn->fn->raw)); |
226 | |
227 | /* If a node has zero dsize, we only have to keep it if it might be the |
228 | node with highest version -- i.e. the one which will end up as f->metadata. |
229 | Note that such nodes won't be REF_UNCHECKED since there are no data to |
230 | check anyway. */ |
231 | if (!tn->fn->size) { |
232 | if (rii->mdata_tn) { |
233 | if (rii->mdata_tn->version < tn->version) { |
234 | /* We had a candidate mdata node already */ |
235 | dbg_readinode("kill old mdata with ver %d\n" , rii->mdata_tn->version); |
236 | jffs2_kill_tn(c, tn: rii->mdata_tn); |
237 | } else { |
238 | dbg_readinode("kill new mdata with ver %d (older than existing %d\n" , |
239 | tn->version, rii->mdata_tn->version); |
240 | jffs2_kill_tn(c, tn); |
241 | return 0; |
242 | } |
243 | } |
244 | rii->mdata_tn = tn; |
245 | dbg_readinode("keep new mdata with ver %d\n" , tn->version); |
246 | return 0; |
247 | } |
248 | |
249 | /* Find the earliest node which _may_ be relevant to this one */ |
250 | this = jffs2_lookup_tn(tn_root: &rii->tn_root, offset: tn->fn->ofs); |
251 | if (this) { |
252 | /* If the node is coincident with another at a lower address, |
253 | back up until the other node is found. It may be relevant */ |
254 | while (this->overlapped) { |
255 | ptn = tn_prev(this); |
256 | if (!ptn) { |
257 | /* |
258 | * We killed a node which set the overlapped |
259 | * flags during the scan. Fix it up. |
260 | */ |
261 | this->overlapped = 0; |
262 | break; |
263 | } |
264 | this = ptn; |
265 | } |
266 | dbg_readinode("'this' found %#04x-%#04x (%s)\n" , this->fn->ofs, this->fn->ofs + this->fn->size, this->fn ? "data" : "hole" ); |
267 | } |
268 | |
269 | while (this) { |
270 | if (this->fn->ofs > fn_end) |
271 | break; |
272 | dbg_readinode("Ponder this ver %d, 0x%x-0x%x\n" , |
273 | this->version, this->fn->ofs, this->fn->size); |
274 | |
275 | if (this->version == tn->version) { |
276 | /* Version number collision means REF_PRISTINE GC. Accept either of them |
277 | as long as the CRC is correct. Check the one we have already... */ |
278 | if (!check_tn_node(c, tn: this)) { |
279 | /* The one we already had was OK. Keep it and throw away the new one */ |
280 | dbg_readinode("Like old node. Throw away new\n" ); |
281 | jffs2_kill_tn(c, tn); |
282 | return 0; |
283 | } else { |
284 | /* Who cares if the new one is good; keep it for now anyway. */ |
285 | dbg_readinode("Like new node. Throw away old\n" ); |
286 | rb_replace_node(victim: &this->rb, new: &tn->rb, root: &rii->tn_root); |
287 | jffs2_kill_tn(c, tn: this); |
288 | /* Same overlapping from in front and behind */ |
289 | return 0; |
290 | } |
291 | } |
292 | if (this->version < tn->version && |
293 | this->fn->ofs >= tn->fn->ofs && |
294 | this->fn->ofs + this->fn->size <= fn_end) { |
295 | /* New node entirely overlaps 'this' */ |
296 | if (check_tn_node(c, tn)) { |
297 | dbg_readinode("new node bad CRC\n" ); |
298 | jffs2_kill_tn(c, tn); |
299 | return 0; |
300 | } |
301 | /* ... and is good. Kill 'this' and any subsequent nodes which are also overlapped */ |
302 | while (this && this->fn->ofs + this->fn->size <= fn_end) { |
303 | struct jffs2_tmp_dnode_info *next = tn_next(this); |
304 | if (this->version < tn->version) { |
305 | tn_erase(this, &rii->tn_root); |
306 | dbg_readinode("Kill overlapped ver %d, 0x%x-0x%x\n" , |
307 | this->version, this->fn->ofs, |
308 | this->fn->ofs+this->fn->size); |
309 | jffs2_kill_tn(c, tn: this); |
310 | } |
311 | this = next; |
312 | } |
313 | dbg_readinode("Done killing overlapped nodes\n" ); |
314 | continue; |
315 | } |
316 | if (this->version > tn->version && |
317 | this->fn->ofs <= tn->fn->ofs && |
318 | this->fn->ofs+this->fn->size >= fn_end) { |
319 | /* New node entirely overlapped by 'this' */ |
320 | if (!check_tn_node(c, tn: this)) { |
321 | dbg_readinode("Good CRC on old node. Kill new\n" ); |
322 | jffs2_kill_tn(c, tn); |
323 | return 0; |
324 | } |
325 | /* ... but 'this' was bad. Replace it... */ |
326 | dbg_readinode("Bad CRC on old overlapping node. Kill it\n" ); |
327 | tn_erase(this, &rii->tn_root); |
328 | jffs2_kill_tn(c, tn: this); |
329 | break; |
330 | } |
331 | |
332 | this = tn_next(this); |
333 | } |
334 | |
335 | /* We neither completely obsoleted nor were completely |
336 | obsoleted by an earlier node. Insert into the tree */ |
337 | { |
338 | struct rb_node *parent; |
339 | struct rb_node **link = &rii->tn_root.rb_node; |
340 | struct jffs2_tmp_dnode_info *insert_point = NULL; |
341 | |
342 | while (*link) { |
343 | parent = *link; |
344 | insert_point = rb_entry(parent, struct jffs2_tmp_dnode_info, rb); |
345 | if (tn->fn->ofs > insert_point->fn->ofs) |
346 | link = &insert_point->rb.rb_right; |
347 | else if (tn->fn->ofs < insert_point->fn->ofs || |
348 | tn->fn->size < insert_point->fn->size) |
349 | link = &insert_point->rb.rb_left; |
350 | else |
351 | link = &insert_point->rb.rb_right; |
352 | } |
353 | rb_link_node(node: &tn->rb, parent: &insert_point->rb, rb_link: link); |
354 | rb_insert_color(&tn->rb, &rii->tn_root); |
355 | } |
356 | |
357 | /* If there's anything behind that overlaps us, note it */ |
358 | this = tn_prev(tn); |
359 | if (this) { |
360 | while (1) { |
361 | if (this->fn->ofs + this->fn->size > tn->fn->ofs) { |
362 | dbg_readinode("Node is overlapped by %p (v %d, 0x%x-0x%x)\n" , |
363 | this, this->version, this->fn->ofs, |
364 | this->fn->ofs+this->fn->size); |
365 | tn->overlapped = 1; |
366 | break; |
367 | } |
368 | if (!this->overlapped) |
369 | break; |
370 | |
371 | ptn = tn_prev(this); |
372 | if (!ptn) { |
373 | /* |
374 | * We killed a node which set the overlapped |
375 | * flags during the scan. Fix it up. |
376 | */ |
377 | this->overlapped = 0; |
378 | break; |
379 | } |
380 | this = ptn; |
381 | } |
382 | } |
383 | |
384 | /* If the new node overlaps anything ahead, note it */ |
385 | this = tn_next(tn); |
386 | while (this && this->fn->ofs < fn_end) { |
387 | this->overlapped = 1; |
388 | dbg_readinode("Node ver %d, 0x%x-0x%x is overlapped\n" , |
389 | this->version, this->fn->ofs, |
390 | this->fn->ofs+this->fn->size); |
391 | this = tn_next(this); |
392 | } |
393 | return 0; |
394 | } |
395 | |
396 | /* Trivial function to remove the last node in the tree. Which by definition |
397 | has no right-hand child — so can be removed just by making its left-hand |
398 | child (if any) take its place under its parent. Since this is only done |
399 | when we're consuming the whole tree, there's no need to use rb_erase() |
400 | and let it worry about adjusting colours and balancing the tree. That |
401 | would just be a waste of time. */ |
402 | static void eat_last(struct rb_root *root, struct rb_node *node) |
403 | { |
404 | struct rb_node *parent = rb_parent(node); |
405 | struct rb_node **link; |
406 | |
407 | /* LAST! */ |
408 | BUG_ON(node->rb_right); |
409 | |
410 | if (!parent) |
411 | link = &root->rb_node; |
412 | else if (node == parent->rb_left) |
413 | link = &parent->rb_left; |
414 | else |
415 | link = &parent->rb_right; |
416 | |
417 | *link = node->rb_left; |
418 | if (node->rb_left) |
419 | node->rb_left->__rb_parent_color = node->__rb_parent_color; |
420 | } |
421 | |
422 | /* We put the version tree in reverse order, so we can use the same eat_last() |
423 | function that we use to consume the tmpnode tree (tn_root). */ |
424 | static void ver_insert(struct rb_root *ver_root, struct jffs2_tmp_dnode_info *tn) |
425 | { |
426 | struct rb_node **link = &ver_root->rb_node; |
427 | struct rb_node *parent = NULL; |
428 | struct jffs2_tmp_dnode_info *this_tn; |
429 | |
430 | while (*link) { |
431 | parent = *link; |
432 | this_tn = rb_entry(parent, struct jffs2_tmp_dnode_info, rb); |
433 | |
434 | if (tn->version > this_tn->version) |
435 | link = &parent->rb_left; |
436 | else |
437 | link = &parent->rb_right; |
438 | } |
439 | dbg_readinode("Link new node at %p (root is %p)\n" , link, ver_root); |
440 | rb_link_node(node: &tn->rb, parent, rb_link: link); |
441 | rb_insert_color(&tn->rb, ver_root); |
442 | } |
443 | |
444 | /* Build final, normal fragtree from tn tree. It doesn't matter which order |
445 | we add nodes to the real fragtree, as long as they don't overlap. And |
446 | having thrown away the majority of overlapped nodes as we went, there |
447 | really shouldn't be many sets of nodes which do overlap. If we start at |
448 | the end, we can use the overlap markers -- we can just eat nodes which |
449 | aren't overlapped, and when we encounter nodes which _do_ overlap we |
450 | sort them all into a temporary tree in version order before replaying them. */ |
451 | static int jffs2_build_inode_fragtree(struct jffs2_sb_info *c, |
452 | struct jffs2_inode_info *f, |
453 | struct jffs2_readinode_info *rii) |
454 | { |
455 | struct jffs2_tmp_dnode_info *pen, *last, *this; |
456 | struct rb_root ver_root = RB_ROOT; |
457 | uint32_t high_ver = 0; |
458 | |
459 | if (rii->mdata_tn) { |
460 | dbg_readinode("potential mdata is ver %d at %p\n" , rii->mdata_tn->version, rii->mdata_tn); |
461 | high_ver = rii->mdata_tn->version; |
462 | rii->latest_ref = rii->mdata_tn->fn->raw; |
463 | } |
464 | #ifdef JFFS2_DBG_READINODE_MESSAGES |
465 | this = tn_last(&rii->tn_root); |
466 | while (this) { |
467 | dbg_readinode("tn %p ver %d range 0x%x-0x%x ov %d\n" , this, this->version, this->fn->ofs, |
468 | this->fn->ofs+this->fn->size, this->overlapped); |
469 | this = tn_prev(this); |
470 | } |
471 | #endif |
472 | pen = tn_last(&rii->tn_root); |
473 | while ((last = pen)) { |
474 | pen = tn_prev(last); |
475 | |
476 | eat_last(root: &rii->tn_root, node: &last->rb); |
477 | ver_insert(ver_root: &ver_root, tn: last); |
478 | |
479 | if (unlikely(last->overlapped)) { |
480 | if (pen) |
481 | continue; |
482 | /* |
483 | * We killed a node which set the overlapped |
484 | * flags during the scan. Fix it up. |
485 | */ |
486 | last->overlapped = 0; |
487 | } |
488 | |
489 | /* Now we have a bunch of nodes in reverse version |
490 | order, in the tree at ver_root. Most of the time, |
491 | there'll actually be only one node in the 'tree', |
492 | in fact. */ |
493 | this = tn_last(&ver_root); |
494 | |
495 | while (this) { |
496 | struct jffs2_tmp_dnode_info *vers_next; |
497 | int ret; |
498 | vers_next = tn_prev(this); |
499 | eat_last(root: &ver_root, node: &this->rb); |
500 | if (check_tn_node(c, tn: this)) { |
501 | dbg_readinode("node ver %d, 0x%x-0x%x failed CRC\n" , |
502 | this->version, this->fn->ofs, |
503 | this->fn->ofs+this->fn->size); |
504 | jffs2_kill_tn(c, tn: this); |
505 | } else { |
506 | if (this->version > high_ver) { |
507 | /* Note that this is different from the other |
508 | highest_version, because this one is only |
509 | counting _valid_ nodes which could give the |
510 | latest inode metadata */ |
511 | high_ver = this->version; |
512 | rii->latest_ref = this->fn->raw; |
513 | } |
514 | dbg_readinode("Add %p (v %d, 0x%x-0x%x, ov %d) to fragtree\n" , |
515 | this, this->version, this->fn->ofs, |
516 | this->fn->ofs+this->fn->size, this->overlapped); |
517 | |
518 | ret = jffs2_add_full_dnode_to_inode(c, f, fn: this->fn); |
519 | if (ret) { |
520 | /* Free the nodes in vers_root; let the caller |
521 | deal with the rest */ |
522 | JFFS2_ERROR("Add node to tree failed %d\n" , ret); |
523 | while (1) { |
524 | vers_next = tn_prev(this); |
525 | if (check_tn_node(c, tn: this)) |
526 | jffs2_mark_node_obsolete(c, raw: this->fn->raw); |
527 | jffs2_free_full_dnode(this->fn); |
528 | jffs2_free_tmp_dnode_info(this); |
529 | this = vers_next; |
530 | if (!this) |
531 | break; |
532 | eat_last(root: &ver_root, node: &vers_next->rb); |
533 | } |
534 | return ret; |
535 | } |
536 | jffs2_free_tmp_dnode_info(this); |
537 | } |
538 | this = vers_next; |
539 | } |
540 | } |
541 | return 0; |
542 | } |
543 | |
544 | static void jffs2_free_tmp_dnode_info_list(struct rb_root *list) |
545 | { |
546 | struct jffs2_tmp_dnode_info *tn, *next; |
547 | |
548 | rbtree_postorder_for_each_entry_safe(tn, next, list, rb) { |
549 | jffs2_free_full_dnode(tn->fn); |
550 | jffs2_free_tmp_dnode_info(tn); |
551 | } |
552 | |
553 | *list = RB_ROOT; |
554 | } |
555 | |
556 | static void jffs2_free_full_dirent_list(struct jffs2_full_dirent *fd) |
557 | { |
558 | struct jffs2_full_dirent *next; |
559 | |
560 | while (fd) { |
561 | next = fd->next; |
562 | jffs2_free_full_dirent(fd); |
563 | fd = next; |
564 | } |
565 | } |
566 | |
567 | /* Returns first valid node after 'ref'. May return 'ref' */ |
568 | static struct jffs2_raw_node_ref *jffs2_first_valid_node(struct jffs2_raw_node_ref *ref) |
569 | { |
570 | while (ref && ref->next_in_ino) { |
571 | if (!ref_obsolete(ref)) |
572 | return ref; |
573 | dbg_noderef("node at 0x%08x is obsoleted. Ignoring.\n" , ref_offset(ref)); |
574 | ref = ref->next_in_ino; |
575 | } |
576 | return NULL; |
577 | } |
578 | |
579 | /* |
580 | * Helper function for jffs2_get_inode_nodes(). |
581 | * It is called every time an directory entry node is found. |
582 | * |
583 | * Returns: 0 on success; |
584 | * negative error code on failure. |
585 | */ |
586 | static inline int read_direntry(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, |
587 | struct jffs2_raw_dirent *rd, size_t read, |
588 | struct jffs2_readinode_info *rii) |
589 | { |
590 | struct jffs2_full_dirent *fd; |
591 | uint32_t crc; |
592 | |
593 | /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */ |
594 | BUG_ON(ref_obsolete(ref)); |
595 | |
596 | crc = crc32(0, rd, sizeof(*rd) - 8); |
597 | if (unlikely(crc != je32_to_cpu(rd->node_crc))) { |
598 | JFFS2_NOTICE("header CRC failed on dirent node at %#08x: read %#08x, calculated %#08x\n" , |
599 | ref_offset(ref), je32_to_cpu(rd->node_crc), crc); |
600 | jffs2_mark_node_obsolete(c, raw: ref); |
601 | return 0; |
602 | } |
603 | |
604 | /* If we've never checked the CRCs on this node, check them now */ |
605 | if (ref_flags(ref) == REF_UNCHECKED) { |
606 | struct jffs2_eraseblock *jeb; |
607 | int len; |
608 | |
609 | /* Sanity check */ |
610 | if (unlikely(PAD((rd->nsize + sizeof(*rd))) != PAD(je32_to_cpu(rd->totlen)))) { |
611 | JFFS2_ERROR("illegal nsize in node at %#08x: nsize %#02x, totlen %#04x\n" , |
612 | ref_offset(ref), rd->nsize, je32_to_cpu(rd->totlen)); |
613 | jffs2_mark_node_obsolete(c, raw: ref); |
614 | return 0; |
615 | } |
616 | |
617 | jeb = &c->blocks[ref->flash_offset / c->sector_size]; |
618 | len = ref_totlen(c, jeb, ref); |
619 | |
620 | spin_lock(lock: &c->erase_completion_lock); |
621 | jeb->used_size += len; |
622 | jeb->unchecked_size -= len; |
623 | c->used_size += len; |
624 | c->unchecked_size -= len; |
625 | ref->flash_offset = ref_offset(ref) | dirent_node_state(rd); |
626 | spin_unlock(lock: &c->erase_completion_lock); |
627 | } |
628 | |
629 | fd = jffs2_alloc_full_dirent(namesize: rd->nsize + 1); |
630 | if (unlikely(!fd)) |
631 | return -ENOMEM; |
632 | |
633 | fd->raw = ref; |
634 | fd->version = je32_to_cpu(rd->version); |
635 | fd->ino = je32_to_cpu(rd->ino); |
636 | fd->type = rd->type; |
637 | |
638 | if (fd->version > rii->highest_version) |
639 | rii->highest_version = fd->version; |
640 | |
641 | /* Pick out the mctime of the latest dirent */ |
642 | if(fd->version > rii->mctime_ver && je32_to_cpu(rd->mctime)) { |
643 | rii->mctime_ver = fd->version; |
644 | rii->latest_mctime = je32_to_cpu(rd->mctime); |
645 | } |
646 | |
647 | /* |
648 | * Copy as much of the name as possible from the raw |
649 | * dirent we've already read from the flash. |
650 | */ |
651 | if (read > sizeof(*rd)) |
652 | memcpy(&fd->name[0], &rd->name[0], |
653 | min_t(uint32_t, rd->nsize, (read - sizeof(*rd)) )); |
654 | |
655 | /* Do we need to copy any more of the name directly from the flash? */ |
656 | if (rd->nsize + sizeof(*rd) > read) { |
657 | /* FIXME: point() */ |
658 | int err; |
659 | int already = read - sizeof(*rd); |
660 | |
661 | err = jffs2_flash_read(c, ofs: (ref_offset(ref)) + read, |
662 | len: rd->nsize - already, retlen: &read, buf: &fd->name[already]); |
663 | if (unlikely(read != rd->nsize - already) && likely(!err)) { |
664 | jffs2_free_full_dirent(fd); |
665 | JFFS2_ERROR("short read: wanted %d bytes, got %zd\n" , |
666 | rd->nsize - already, read); |
667 | return -EIO; |
668 | } |
669 | |
670 | if (unlikely(err)) { |
671 | JFFS2_ERROR("read remainder of name: error %d\n" , err); |
672 | jffs2_free_full_dirent(fd); |
673 | return -EIO; |
674 | } |
675 | |
676 | #ifdef CONFIG_JFFS2_SUMMARY |
677 | /* |
678 | * we use CONFIG_JFFS2_SUMMARY because without it, we |
679 | * have checked it while mounting |
680 | */ |
681 | crc = crc32(0, fd->name, rd->nsize); |
682 | if (unlikely(crc != je32_to_cpu(rd->name_crc))) { |
683 | JFFS2_NOTICE("name CRC failed on dirent node at" |
684 | "%#08x: read %#08x,calculated %#08x\n" , |
685 | ref_offset(ref), je32_to_cpu(rd->node_crc), crc); |
686 | jffs2_mark_node_obsolete(c, raw: ref); |
687 | jffs2_free_full_dirent(fd); |
688 | return 0; |
689 | } |
690 | #endif |
691 | } |
692 | |
693 | fd->nhash = full_name_hash(NULL, fd->name, rd->nsize); |
694 | fd->next = NULL; |
695 | fd->name[rd->nsize] = '\0'; |
696 | |
697 | /* |
698 | * Wheee. We now have a complete jffs2_full_dirent structure, with |
699 | * the name in it and everything. Link it into the list |
700 | */ |
701 | jffs2_add_fd_to_list(c, new: fd, list: &rii->fds); |
702 | |
703 | return 0; |
704 | } |
705 | |
706 | /* |
707 | * Helper function for jffs2_get_inode_nodes(). |
708 | * It is called every time an inode node is found. |
709 | * |
710 | * Returns: 0 on success (possibly after marking a bad node obsolete); |
711 | * negative error code on failure. |
712 | */ |
713 | static inline int read_dnode(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, |
714 | struct jffs2_raw_inode *rd, int rdlen, |
715 | struct jffs2_readinode_info *rii) |
716 | { |
717 | struct jffs2_tmp_dnode_info *tn; |
718 | uint32_t len, csize; |
719 | int ret = 0; |
720 | uint32_t crc; |
721 | |
722 | /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */ |
723 | BUG_ON(ref_obsolete(ref)); |
724 | |
725 | crc = crc32(0, rd, sizeof(*rd) - 8); |
726 | if (unlikely(crc != je32_to_cpu(rd->node_crc))) { |
727 | JFFS2_NOTICE("node CRC failed on dnode at %#08x: read %#08x, calculated %#08x\n" , |
728 | ref_offset(ref), je32_to_cpu(rd->node_crc), crc); |
729 | jffs2_mark_node_obsolete(c, raw: ref); |
730 | return 0; |
731 | } |
732 | |
733 | tn = jffs2_alloc_tmp_dnode_info(); |
734 | if (!tn) { |
735 | JFFS2_ERROR("failed to allocate tn (%zu bytes).\n" , sizeof(*tn)); |
736 | return -ENOMEM; |
737 | } |
738 | |
739 | tn->partial_crc = 0; |
740 | csize = je32_to_cpu(rd->csize); |
741 | |
742 | /* If we've never checked the CRCs on this node, check them now */ |
743 | if (ref_flags(ref) == REF_UNCHECKED) { |
744 | |
745 | /* Sanity checks */ |
746 | if (unlikely(je32_to_cpu(rd->offset) > je32_to_cpu(rd->isize)) || |
747 | unlikely(PAD(je32_to_cpu(rd->csize) + sizeof(*rd)) != PAD(je32_to_cpu(rd->totlen)))) { |
748 | JFFS2_WARNING("inode node header CRC is corrupted at %#08x\n" , ref_offset(ref)); |
749 | jffs2_dbg_dump_node(c, ref_offset(ref)); |
750 | jffs2_mark_node_obsolete(c, raw: ref); |
751 | goto free_out; |
752 | } |
753 | |
754 | if (jffs2_is_writebuffered(c) && csize != 0) { |
755 | /* At this point we are supposed to check the data CRC |
756 | * of our unchecked node. But thus far, we do not |
757 | * know whether the node is valid or obsolete. To |
758 | * figure this out, we need to walk all the nodes of |
759 | * the inode and build the inode fragtree. We don't |
760 | * want to spend time checking data of nodes which may |
761 | * later be found to be obsolete. So we put off the full |
762 | * data CRC checking until we have read all the inode |
763 | * nodes and have started building the fragtree. |
764 | * |
765 | * The fragtree is being built starting with nodes |
766 | * having the highest version number, so we'll be able |
767 | * to detect whether a node is valid (i.e., it is not |
768 | * overlapped by a node with higher version) or not. |
769 | * And we'll be able to check only those nodes, which |
770 | * are not obsolete. |
771 | * |
772 | * Of course, this optimization only makes sense in case |
773 | * of NAND flashes (or other flashes with |
774 | * !jffs2_can_mark_obsolete()), since on NOR flashes |
775 | * nodes are marked obsolete physically. |
776 | * |
777 | * Since NAND flashes (or other flashes with |
778 | * jffs2_is_writebuffered(c)) are anyway read by |
779 | * fractions of c->wbuf_pagesize, and we have just read |
780 | * the node header, it is likely that the starting part |
781 | * of the node data is also read when we read the |
782 | * header. So we don't mind to check the CRC of the |
783 | * starting part of the data of the node now, and check |
784 | * the second part later (in jffs2_check_node_data()). |
785 | * Of course, we will not need to re-read and re-check |
786 | * the NAND page which we have just read. This is why we |
787 | * read the whole NAND page at jffs2_get_inode_nodes(), |
788 | * while we needed only the node header. |
789 | */ |
790 | unsigned char *buf; |
791 | |
792 | /* 'buf' will point to the start of data */ |
793 | buf = (unsigned char *)rd + sizeof(*rd); |
794 | /* len will be the read data length */ |
795 | len = min_t(uint32_t, rdlen - sizeof(*rd), csize); |
796 | tn->partial_crc = crc32(0, buf, len); |
797 | |
798 | dbg_readinode("Calculates CRC (%#08x) for %d bytes, csize %d\n" , tn->partial_crc, len, csize); |
799 | |
800 | /* If we actually calculated the whole data CRC |
801 | * and it is wrong, drop the node. */ |
802 | if (len >= csize && unlikely(tn->partial_crc != je32_to_cpu(rd->data_crc))) { |
803 | JFFS2_NOTICE("wrong data CRC in data node at 0x%08x: read %#08x, calculated %#08x.\n" , |
804 | ref_offset(ref), tn->partial_crc, je32_to_cpu(rd->data_crc)); |
805 | jffs2_mark_node_obsolete(c, raw: ref); |
806 | goto free_out; |
807 | } |
808 | |
809 | } else if (csize == 0) { |
810 | /* |
811 | * We checked the header CRC. If the node has no data, adjust |
812 | * the space accounting now. For other nodes this will be done |
813 | * later either when the node is marked obsolete or when its |
814 | * data is checked. |
815 | */ |
816 | struct jffs2_eraseblock *jeb; |
817 | |
818 | dbg_readinode("the node has no data.\n" ); |
819 | jeb = &c->blocks[ref->flash_offset / c->sector_size]; |
820 | len = ref_totlen(c, jeb, ref); |
821 | |
822 | spin_lock(lock: &c->erase_completion_lock); |
823 | jeb->used_size += len; |
824 | jeb->unchecked_size -= len; |
825 | c->used_size += len; |
826 | c->unchecked_size -= len; |
827 | ref->flash_offset = ref_offset(ref) | REF_NORMAL; |
828 | spin_unlock(lock: &c->erase_completion_lock); |
829 | } |
830 | } |
831 | |
832 | tn->fn = jffs2_alloc_full_dnode(); |
833 | if (!tn->fn) { |
834 | JFFS2_ERROR("alloc fn failed\n" ); |
835 | ret = -ENOMEM; |
836 | goto free_out; |
837 | } |
838 | |
839 | tn->version = je32_to_cpu(rd->version); |
840 | tn->fn->ofs = je32_to_cpu(rd->offset); |
841 | tn->data_crc = je32_to_cpu(rd->data_crc); |
842 | tn->csize = csize; |
843 | tn->fn->raw = ref; |
844 | tn->overlapped = 0; |
845 | |
846 | if (tn->version > rii->highest_version) |
847 | rii->highest_version = tn->version; |
848 | |
849 | /* There was a bug where we wrote hole nodes out with |
850 | csize/dsize swapped. Deal with it */ |
851 | if (rd->compr == JFFS2_COMPR_ZERO && !je32_to_cpu(rd->dsize) && csize) |
852 | tn->fn->size = csize; |
853 | else // normal case... |
854 | tn->fn->size = je32_to_cpu(rd->dsize); |
855 | |
856 | dbg_readinode2("dnode @%08x: ver %u, offset %#04x, dsize %#04x, csize %#04x\n" , |
857 | ref_offset(ref), je32_to_cpu(rd->version), |
858 | je32_to_cpu(rd->offset), je32_to_cpu(rd->dsize), csize); |
859 | |
860 | ret = jffs2_add_tn_to_tree(c, rii, tn); |
861 | |
862 | if (ret) { |
863 | jffs2_free_full_dnode(tn->fn); |
864 | free_out: |
865 | jffs2_free_tmp_dnode_info(tn); |
866 | return ret; |
867 | } |
868 | #ifdef JFFS2_DBG_READINODE2_MESSAGES |
869 | dbg_readinode2("After adding ver %d:\n" , je32_to_cpu(rd->version)); |
870 | tn = tn_first(&rii->tn_root); |
871 | while (tn) { |
872 | dbg_readinode2("%p: v %d r 0x%x-0x%x ov %d\n" , |
873 | tn, tn->version, tn->fn->ofs, |
874 | tn->fn->ofs+tn->fn->size, tn->overlapped); |
875 | tn = tn_next(tn); |
876 | } |
877 | #endif |
878 | return 0; |
879 | } |
880 | |
881 | /* |
882 | * Helper function for jffs2_get_inode_nodes(). |
883 | * It is called every time an unknown node is found. |
884 | * |
885 | * Returns: 0 on success; |
886 | * negative error code on failure. |
887 | */ |
888 | static inline int read_unknown(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, struct jffs2_unknown_node *un) |
889 | { |
890 | /* We don't mark unknown nodes as REF_UNCHECKED */ |
891 | if (ref_flags(ref) == REF_UNCHECKED) { |
892 | JFFS2_ERROR("REF_UNCHECKED but unknown node at %#08x\n" , |
893 | ref_offset(ref)); |
894 | JFFS2_ERROR("Node is {%04x,%04x,%08x,%08x}. Please report this error.\n" , |
895 | je16_to_cpu(un->magic), je16_to_cpu(un->nodetype), |
896 | je32_to_cpu(un->totlen), je32_to_cpu(un->hdr_crc)); |
897 | jffs2_mark_node_obsolete(c, raw: ref); |
898 | return 0; |
899 | } |
900 | |
901 | un->nodetype = cpu_to_je16(JFFS2_NODE_ACCURATE | je16_to_cpu(un->nodetype)); |
902 | |
903 | switch(je16_to_cpu(un->nodetype) & JFFS2_COMPAT_MASK) { |
904 | |
905 | case JFFS2_FEATURE_INCOMPAT: |
906 | JFFS2_ERROR("unknown INCOMPAT nodetype %#04X at %#08x\n" , |
907 | je16_to_cpu(un->nodetype), ref_offset(ref)); |
908 | /* EEP */ |
909 | BUG(); |
910 | break; |
911 | |
912 | case JFFS2_FEATURE_ROCOMPAT: |
913 | JFFS2_ERROR("unknown ROCOMPAT nodetype %#04X at %#08x\n" , |
914 | je16_to_cpu(un->nodetype), ref_offset(ref)); |
915 | BUG_ON(!(c->flags & JFFS2_SB_FLAG_RO)); |
916 | break; |
917 | |
918 | case JFFS2_FEATURE_RWCOMPAT_COPY: |
919 | JFFS2_NOTICE("unknown RWCOMPAT_COPY nodetype %#04X at %#08x\n" , |
920 | je16_to_cpu(un->nodetype), ref_offset(ref)); |
921 | break; |
922 | |
923 | case JFFS2_FEATURE_RWCOMPAT_DELETE: |
924 | JFFS2_NOTICE("unknown RWCOMPAT_DELETE nodetype %#04X at %#08x\n" , |
925 | je16_to_cpu(un->nodetype), ref_offset(ref)); |
926 | jffs2_mark_node_obsolete(c, raw: ref); |
927 | return 0; |
928 | } |
929 | |
930 | return 0; |
931 | } |
932 | |
933 | /* |
934 | * Helper function for jffs2_get_inode_nodes(). |
935 | * The function detects whether more data should be read and reads it if yes. |
936 | * |
937 | * Returns: 0 on success; |
938 | * negative error code on failure. |
939 | */ |
940 | static int read_more(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, |
941 | int needed_len, int *rdlen, unsigned char *buf) |
942 | { |
943 | int err, to_read = needed_len - *rdlen; |
944 | size_t retlen; |
945 | uint32_t offs; |
946 | |
947 | if (jffs2_is_writebuffered(c)) { |
948 | int rem = to_read % c->wbuf_pagesize; |
949 | |
950 | if (rem) |
951 | to_read += c->wbuf_pagesize - rem; |
952 | } |
953 | |
954 | /* We need to read more data */ |
955 | offs = ref_offset(ref) + *rdlen; |
956 | |
957 | dbg_readinode("read more %d bytes\n" , to_read); |
958 | |
959 | err = jffs2_flash_read(c, ofs: offs, len: to_read, retlen: &retlen, buf: buf + *rdlen); |
960 | if (err) { |
961 | JFFS2_ERROR("can not read %d bytes from 0x%08x, " |
962 | "error code: %d.\n" , to_read, offs, err); |
963 | return err; |
964 | } |
965 | |
966 | if (retlen < to_read) { |
967 | JFFS2_ERROR("short read at %#08x: %zu instead of %d.\n" , |
968 | offs, retlen, to_read); |
969 | return -EIO; |
970 | } |
971 | |
972 | *rdlen += to_read; |
973 | return 0; |
974 | } |
975 | |
976 | /* Get tmp_dnode_info and full_dirent for all non-obsolete nodes associated |
977 | with this ino. Perform a preliminary ordering on data nodes, throwing away |
978 | those which are completely obsoleted by newer ones. The naïve approach we |
979 | use to take of just returning them _all_ in version order will cause us to |
980 | run out of memory in certain degenerate cases. */ |
981 | static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_info *f, |
982 | struct jffs2_readinode_info *rii) |
983 | { |
984 | struct jffs2_raw_node_ref *ref, *valid_ref; |
985 | unsigned char *buf = NULL; |
986 | union jffs2_node_union *node; |
987 | size_t retlen; |
988 | int len, err; |
989 | |
990 | rii->mctime_ver = 0; |
991 | |
992 | dbg_readinode("ino #%u\n" , f->inocache->ino); |
993 | |
994 | /* FIXME: in case of NOR and available ->point() this |
995 | * needs to be fixed. */ |
996 | len = sizeof(union jffs2_node_union) + c->wbuf_pagesize; |
997 | buf = kmalloc(size: len, GFP_KERNEL); |
998 | if (!buf) |
999 | return -ENOMEM; |
1000 | |
1001 | spin_lock(lock: &c->erase_completion_lock); |
1002 | valid_ref = jffs2_first_valid_node(ref: f->inocache->nodes); |
1003 | if (!valid_ref && f->inocache->ino != 1) |
1004 | JFFS2_WARNING("Eep. No valid nodes for ino #%u.\n" , f->inocache->ino); |
1005 | while (valid_ref) { |
1006 | /* We can hold a pointer to a non-obsolete node without the spinlock, |
1007 | but _obsolete_ nodes may disappear at any time, if the block |
1008 | they're in gets erased. So if we mark 'ref' obsolete while we're |
1009 | not holding the lock, it can go away immediately. For that reason, |
1010 | we find the next valid node first, before processing 'ref'. |
1011 | */ |
1012 | ref = valid_ref; |
1013 | valid_ref = jffs2_first_valid_node(ref: ref->next_in_ino); |
1014 | spin_unlock(lock: &c->erase_completion_lock); |
1015 | |
1016 | cond_resched(); |
1017 | |
1018 | /* |
1019 | * At this point we don't know the type of the node we're going |
1020 | * to read, so we do not know the size of its header. In order |
1021 | * to minimize the amount of flash IO we assume the header is |
1022 | * of size = JFFS2_MIN_NODE_HEADER. |
1023 | */ |
1024 | len = JFFS2_MIN_NODE_HEADER; |
1025 | if (jffs2_is_writebuffered(c)) { |
1026 | int end, rem; |
1027 | |
1028 | /* |
1029 | * We are about to read JFFS2_MIN_NODE_HEADER bytes, |
1030 | * but this flash has some minimal I/O unit. It is |
1031 | * possible that we'll need to read more soon, so read |
1032 | * up to the next min. I/O unit, in order not to |
1033 | * re-read the same min. I/O unit twice. |
1034 | */ |
1035 | end = ref_offset(ref) + len; |
1036 | rem = end % c->wbuf_pagesize; |
1037 | if (rem) |
1038 | end += c->wbuf_pagesize - rem; |
1039 | len = end - ref_offset(ref); |
1040 | } |
1041 | |
1042 | dbg_readinode("read %d bytes at %#08x(%d).\n" , len, ref_offset(ref), ref_flags(ref)); |
1043 | |
1044 | /* FIXME: point() */ |
1045 | err = jffs2_flash_read(c, ref_offset(ref), len, retlen: &retlen, buf); |
1046 | if (err) { |
1047 | JFFS2_ERROR("can not read %d bytes from 0x%08x, error code: %d.\n" , len, ref_offset(ref), err); |
1048 | goto free_out; |
1049 | } |
1050 | |
1051 | if (retlen < len) { |
1052 | JFFS2_ERROR("short read at %#08x: %zu instead of %d.\n" , ref_offset(ref), retlen, len); |
1053 | err = -EIO; |
1054 | goto free_out; |
1055 | } |
1056 | |
1057 | node = (union jffs2_node_union *)buf; |
1058 | |
1059 | /* No need to mask in the valid bit; it shouldn't be invalid */ |
1060 | if (je32_to_cpu(node->u.hdr_crc) != crc32(0, node, sizeof(node->u)-4)) { |
1061 | JFFS2_NOTICE("Node header CRC failed at %#08x. {%04x,%04x,%08x,%08x}\n" , |
1062 | ref_offset(ref), je16_to_cpu(node->u.magic), |
1063 | je16_to_cpu(node->u.nodetype), |
1064 | je32_to_cpu(node->u.totlen), |
1065 | je32_to_cpu(node->u.hdr_crc)); |
1066 | jffs2_dbg_dump_node(c, ref_offset(ref)); |
1067 | jffs2_mark_node_obsolete(c, raw: ref); |
1068 | goto cont; |
1069 | } |
1070 | if (je16_to_cpu(node->u.magic) != JFFS2_MAGIC_BITMASK) { |
1071 | /* Not a JFFS2 node, whinge and move on */ |
1072 | JFFS2_NOTICE("Wrong magic bitmask 0x%04x in node header at %#08x.\n" , |
1073 | je16_to_cpu(node->u.magic), ref_offset(ref)); |
1074 | jffs2_mark_node_obsolete(c, raw: ref); |
1075 | goto cont; |
1076 | } |
1077 | |
1078 | switch (je16_to_cpu(node->u.nodetype)) { |
1079 | |
1080 | case JFFS2_NODETYPE_DIRENT: |
1081 | |
1082 | if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_raw_dirent) && |
1083 | len < sizeof(struct jffs2_raw_dirent)) { |
1084 | err = read_more(c, ref, needed_len: sizeof(struct jffs2_raw_dirent), rdlen: &len, buf); |
1085 | if (unlikely(err)) |
1086 | goto free_out; |
1087 | } |
1088 | |
1089 | err = read_direntry(c, ref, rd: &node->d, read: retlen, rii); |
1090 | if (unlikely(err)) |
1091 | goto free_out; |
1092 | |
1093 | break; |
1094 | |
1095 | case JFFS2_NODETYPE_INODE: |
1096 | |
1097 | if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_raw_inode) && |
1098 | len < sizeof(struct jffs2_raw_inode)) { |
1099 | err = read_more(c, ref, needed_len: sizeof(struct jffs2_raw_inode), rdlen: &len, buf); |
1100 | if (unlikely(err)) |
1101 | goto free_out; |
1102 | } |
1103 | |
1104 | err = read_dnode(c, ref, rd: &node->i, rdlen: len, rii); |
1105 | if (unlikely(err)) |
1106 | goto free_out; |
1107 | |
1108 | break; |
1109 | |
1110 | default: |
1111 | if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_unknown_node) && |
1112 | len < sizeof(struct jffs2_unknown_node)) { |
1113 | err = read_more(c, ref, needed_len: sizeof(struct jffs2_unknown_node), rdlen: &len, buf); |
1114 | if (unlikely(err)) |
1115 | goto free_out; |
1116 | } |
1117 | |
1118 | err = read_unknown(c, ref, un: &node->u); |
1119 | if (unlikely(err)) |
1120 | goto free_out; |
1121 | |
1122 | } |
1123 | cont: |
1124 | spin_lock(lock: &c->erase_completion_lock); |
1125 | } |
1126 | |
1127 | spin_unlock(lock: &c->erase_completion_lock); |
1128 | kfree(objp: buf); |
1129 | |
1130 | f->highest_version = rii->highest_version; |
1131 | |
1132 | dbg_readinode("nodes of inode #%u were read, the highest version is %u, latest_mctime %u, mctime_ver %u.\n" , |
1133 | f->inocache->ino, rii->highest_version, rii->latest_mctime, |
1134 | rii->mctime_ver); |
1135 | return 0; |
1136 | |
1137 | free_out: |
1138 | jffs2_free_tmp_dnode_info_list(list: &rii->tn_root); |
1139 | jffs2_free_full_dirent_list(fd: rii->fds); |
1140 | rii->fds = NULL; |
1141 | kfree(objp: buf); |
1142 | return err; |
1143 | } |
1144 | |
1145 | static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c, |
1146 | struct jffs2_inode_info *f, |
1147 | struct jffs2_raw_inode *latest_node) |
1148 | { |
1149 | struct jffs2_readinode_info rii; |
1150 | uint32_t crc, new_size; |
1151 | size_t retlen; |
1152 | int ret; |
1153 | |
1154 | dbg_readinode("ino #%u pino/nlink is %d\n" , f->inocache->ino, |
1155 | f->inocache->pino_nlink); |
1156 | |
1157 | memset(&rii, 0, sizeof(rii)); |
1158 | |
1159 | /* Grab all nodes relevant to this ino */ |
1160 | ret = jffs2_get_inode_nodes(c, f, rii: &rii); |
1161 | |
1162 | if (ret) { |
1163 | JFFS2_ERROR("cannot read nodes for ino %u, returned error is %d\n" , f->inocache->ino, ret); |
1164 | if (f->inocache->state == INO_STATE_READING) |
1165 | jffs2_set_inocache_state(c, ic: f->inocache, INO_STATE_CHECKEDABSENT); |
1166 | return ret; |
1167 | } |
1168 | |
1169 | ret = jffs2_build_inode_fragtree(c, f, rii: &rii); |
1170 | if (ret) { |
1171 | JFFS2_ERROR("Failed to build final fragtree for inode #%u: error %d\n" , |
1172 | f->inocache->ino, ret); |
1173 | if (f->inocache->state == INO_STATE_READING) |
1174 | jffs2_set_inocache_state(c, ic: f->inocache, INO_STATE_CHECKEDABSENT); |
1175 | jffs2_free_tmp_dnode_info_list(list: &rii.tn_root); |
1176 | /* FIXME: We could at least crc-check them all */ |
1177 | if (rii.mdata_tn) { |
1178 | jffs2_free_full_dnode(rii.mdata_tn->fn); |
1179 | jffs2_free_tmp_dnode_info(rii.mdata_tn); |
1180 | rii.mdata_tn = NULL; |
1181 | } |
1182 | return ret; |
1183 | } |
1184 | |
1185 | if (rii.mdata_tn) { |
1186 | if (rii.mdata_tn->fn->raw == rii.latest_ref) { |
1187 | f->metadata = rii.mdata_tn->fn; |
1188 | jffs2_free_tmp_dnode_info(rii.mdata_tn); |
1189 | } else { |
1190 | jffs2_kill_tn(c, tn: rii.mdata_tn); |
1191 | } |
1192 | rii.mdata_tn = NULL; |
1193 | } |
1194 | |
1195 | f->dents = rii.fds; |
1196 | |
1197 | jffs2_dbg_fragtree_paranoia_check_nolock(f); |
1198 | |
1199 | if (unlikely(!rii.latest_ref)) { |
1200 | /* No data nodes for this inode. */ |
1201 | if (f->inocache->ino != 1) { |
1202 | JFFS2_WARNING("no data nodes found for ino #%u\n" , f->inocache->ino); |
1203 | if (!rii.fds) { |
1204 | if (f->inocache->state == INO_STATE_READING) |
1205 | jffs2_set_inocache_state(c, ic: f->inocache, INO_STATE_CHECKEDABSENT); |
1206 | return -EIO; |
1207 | } |
1208 | JFFS2_NOTICE("but it has children so we fake some modes for it\n" ); |
1209 | } |
1210 | latest_node->mode = cpu_to_jemode(S_IFDIR|S_IRUGO|S_IWUSR|S_IXUGO); |
1211 | latest_node->version = cpu_to_je32(0); |
1212 | latest_node->atime = latest_node->ctime = latest_node->mtime = cpu_to_je32(0); |
1213 | latest_node->isize = cpu_to_je32(0); |
1214 | latest_node->gid = cpu_to_je16(0); |
1215 | latest_node->uid = cpu_to_je16(0); |
1216 | if (f->inocache->state == INO_STATE_READING) |
1217 | jffs2_set_inocache_state(c, f->inocache, INO_STATE_PRESENT); |
1218 | return 0; |
1219 | } |
1220 | |
1221 | ret = jffs2_flash_read(c, ref_offset(rii.latest_ref), sizeof(*latest_node), &retlen, (void *)latest_node); |
1222 | if (ret || retlen != sizeof(*latest_node)) { |
1223 | JFFS2_ERROR("failed to read from flash: error %d, %zd of %zd bytes read\n" , |
1224 | ret, retlen, sizeof(*latest_node)); |
1225 | /* FIXME: If this fails, there seems to be a memory leak. Find it. */ |
1226 | return ret ? ret : -EIO; |
1227 | } |
1228 | |
1229 | crc = crc32(0, latest_node, sizeof(*latest_node)-8); |
1230 | if (crc != je32_to_cpu(latest_node->node_crc)) { |
1231 | JFFS2_ERROR("CRC failed for read_inode of inode %u at physical location 0x%x\n" , |
1232 | f->inocache->ino, ref_offset(rii.latest_ref)); |
1233 | return -EIO; |
1234 | } |
1235 | |
1236 | switch(jemode_to_cpu(latest_node->mode) & S_IFMT) { |
1237 | case S_IFDIR: |
1238 | if (rii.mctime_ver > je32_to_cpu(latest_node->version)) { |
1239 | /* The times in the latest_node are actually older than |
1240 | mctime in the latest dirent. Cheat. */ |
1241 | latest_node->ctime = latest_node->mtime = cpu_to_je32(rii.latest_mctime); |
1242 | } |
1243 | break; |
1244 | |
1245 | |
1246 | case S_IFREG: |
1247 | /* If it was a regular file, truncate it to the latest node's isize */ |
1248 | new_size = jffs2_truncate_fragtree(c, &f->fragtree, je32_to_cpu(latest_node->isize)); |
1249 | if (new_size != je32_to_cpu(latest_node->isize)) { |
1250 | JFFS2_WARNING("Truncating ino #%u to %d bytes failed because it only had %d bytes to start with!\n" , |
1251 | f->inocache->ino, je32_to_cpu(latest_node->isize), new_size); |
1252 | latest_node->isize = cpu_to_je32(new_size); |
1253 | } |
1254 | break; |
1255 | |
1256 | case S_IFLNK: |
1257 | /* Hack to work around broken isize in old symlink code. |
1258 | Remove this when dwmw2 comes to his senses and stops |
1259 | symlinks from being an entirely gratuitous special |
1260 | case. */ |
1261 | if (!je32_to_cpu(latest_node->isize)) |
1262 | latest_node->isize = latest_node->dsize; |
1263 | |
1264 | if (f->inocache->state != INO_STATE_CHECKING) { |
1265 | /* Symlink's inode data is the target path. Read it and |
1266 | * keep in RAM to facilitate quick follow symlink |
1267 | * operation. */ |
1268 | uint32_t csize = je32_to_cpu(latest_node->csize); |
1269 | if (csize > JFFS2_MAX_NAME_LEN) |
1270 | return -ENAMETOOLONG; |
1271 | f->target = kmalloc(csize + 1, GFP_KERNEL); |
1272 | if (!f->target) { |
1273 | JFFS2_ERROR("can't allocate %u bytes of memory for the symlink target path cache\n" , csize); |
1274 | return -ENOMEM; |
1275 | } |
1276 | |
1277 | ret = jffs2_flash_read(c, ref_offset(rii.latest_ref) + sizeof(*latest_node), |
1278 | csize, &retlen, (char *)f->target); |
1279 | |
1280 | if (ret || retlen != csize) { |
1281 | if (retlen != csize) |
1282 | ret = -EIO; |
1283 | kfree(f->target); |
1284 | f->target = NULL; |
1285 | return ret; |
1286 | } |
1287 | |
1288 | f->target[csize] = '\0'; |
1289 | dbg_readinode("symlink's target '%s' cached\n" , f->target); |
1290 | } |
1291 | |
1292 | fallthrough; |
1293 | |
1294 | case S_IFBLK: |
1295 | case S_IFCHR: |
1296 | /* Certain inode types should have only one data node, and it's |
1297 | kept as the metadata node */ |
1298 | if (f->metadata) { |
1299 | JFFS2_ERROR("Argh. Special inode #%u with mode 0%o had metadata node\n" , |
1300 | f->inocache->ino, jemode_to_cpu(latest_node->mode)); |
1301 | return -EIO; |
1302 | } |
1303 | if (!frag_first(&f->fragtree)) { |
1304 | JFFS2_ERROR("Argh. Special inode #%u with mode 0%o has no fragments\n" , |
1305 | f->inocache->ino, jemode_to_cpu(latest_node->mode)); |
1306 | return -EIO; |
1307 | } |
1308 | /* ASSERT: f->fraglist != NULL */ |
1309 | if (frag_next(frag_first(&f->fragtree))) { |
1310 | JFFS2_ERROR("Argh. Special inode #%u with mode 0x%x had more than one node\n" , |
1311 | f->inocache->ino, jemode_to_cpu(latest_node->mode)); |
1312 | /* FIXME: Deal with it - check crc32, check for duplicate node, check times and discard the older one */ |
1313 | return -EIO; |
1314 | } |
1315 | /* OK. We're happy */ |
1316 | f->metadata = frag_first(&f->fragtree)->node; |
1317 | jffs2_free_node_frag(frag_first(&f->fragtree)); |
1318 | f->fragtree = RB_ROOT; |
1319 | break; |
1320 | } |
1321 | if (f->inocache->state == INO_STATE_READING) |
1322 | jffs2_set_inocache_state(c, f->inocache, INO_STATE_PRESENT); |
1323 | |
1324 | return 0; |
1325 | } |
1326 | |
1327 | /* Scan the list of all nodes present for this ino, build map of versions, etc. */ |
1328 | int jffs2_do_read_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, |
1329 | uint32_t ino, struct jffs2_raw_inode *latest_node) |
1330 | { |
1331 | dbg_readinode("read inode #%u\n" , ino); |
1332 | |
1333 | retry_inocache: |
1334 | spin_lock(lock: &c->inocache_lock); |
1335 | f->inocache = jffs2_get_ino_cache(c, ino); |
1336 | |
1337 | if (f->inocache) { |
1338 | /* Check its state. We may need to wait before we can use it */ |
1339 | switch(f->inocache->state) { |
1340 | case INO_STATE_UNCHECKED: |
1341 | case INO_STATE_CHECKEDABSENT: |
1342 | f->inocache->state = INO_STATE_READING; |
1343 | break; |
1344 | |
1345 | case INO_STATE_CHECKING: |
1346 | case INO_STATE_GC: |
1347 | /* If it's in either of these states, we need |
1348 | to wait for whoever's got it to finish and |
1349 | put it back. */ |
1350 | dbg_readinode("waiting for ino #%u in state %d\n" , ino, f->inocache->state); |
1351 | sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock); |
1352 | goto retry_inocache; |
1353 | |
1354 | case INO_STATE_READING: |
1355 | case INO_STATE_PRESENT: |
1356 | /* Eep. This should never happen. It can |
1357 | happen if Linux calls read_inode() again |
1358 | before clear_inode() has finished though. */ |
1359 | JFFS2_ERROR("Eep. Trying to read_inode #%u when it's already in state %d!\n" , ino, f->inocache->state); |
1360 | /* Fail. That's probably better than allowing it to succeed */ |
1361 | f->inocache = NULL; |
1362 | break; |
1363 | |
1364 | default: |
1365 | BUG(); |
1366 | } |
1367 | } |
1368 | spin_unlock(lock: &c->inocache_lock); |
1369 | |
1370 | if (!f->inocache && ino == 1) { |
1371 | /* Special case - no root inode on medium */ |
1372 | f->inocache = jffs2_alloc_inode_cache(); |
1373 | if (!f->inocache) { |
1374 | JFFS2_ERROR("cannot allocate inocache for root inode\n" ); |
1375 | return -ENOMEM; |
1376 | } |
1377 | dbg_readinode("creating inocache for root inode\n" ); |
1378 | memset(f->inocache, 0, sizeof(struct jffs2_inode_cache)); |
1379 | f->inocache->ino = f->inocache->pino_nlink = 1; |
1380 | f->inocache->nodes = (struct jffs2_raw_node_ref *)f->inocache; |
1381 | f->inocache->state = INO_STATE_READING; |
1382 | jffs2_add_ino_cache(c, new: f->inocache); |
1383 | } |
1384 | if (!f->inocache) { |
1385 | JFFS2_ERROR("requested to read a nonexistent ino %u\n" , ino); |
1386 | return -ENOENT; |
1387 | } |
1388 | |
1389 | return jffs2_do_read_inode_internal(c, f, latest_node); |
1390 | } |
1391 | |
1392 | int jffs2_do_crccheck_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic) |
1393 | { |
1394 | struct jffs2_raw_inode n; |
1395 | struct jffs2_inode_info *f = kzalloc(size: sizeof(*f), GFP_KERNEL); |
1396 | int ret; |
1397 | |
1398 | if (!f) |
1399 | return -ENOMEM; |
1400 | |
1401 | mutex_init(&f->sem); |
1402 | mutex_lock(&f->sem); |
1403 | f->inocache = ic; |
1404 | |
1405 | ret = jffs2_do_read_inode_internal(c, f, latest_node: &n); |
1406 | mutex_unlock(lock: &f->sem); |
1407 | jffs2_do_clear_inode(c, f); |
1408 | jffs2_xattr_do_crccheck_inode(c, ic); |
1409 | kfree (objp: f); |
1410 | return ret; |
1411 | } |
1412 | |
1413 | void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f) |
1414 | { |
1415 | struct jffs2_full_dirent *fd, *fds; |
1416 | int deleted; |
1417 | |
1418 | jffs2_xattr_delete_inode(c, ic: f->inocache); |
1419 | mutex_lock(&f->sem); |
1420 | deleted = f->inocache && !f->inocache->pino_nlink; |
1421 | |
1422 | if (f->inocache && f->inocache->state != INO_STATE_CHECKING) |
1423 | jffs2_set_inocache_state(c, ic: f->inocache, INO_STATE_CLEARING); |
1424 | |
1425 | if (f->metadata) { |
1426 | if (deleted) |
1427 | jffs2_mark_node_obsolete(c, raw: f->metadata->raw); |
1428 | jffs2_free_full_dnode(f->metadata); |
1429 | } |
1430 | |
1431 | jffs2_kill_fragtree(root: &f->fragtree, c_delete: deleted?c:NULL); |
1432 | |
1433 | fds = f->dents; |
1434 | while(fds) { |
1435 | fd = fds; |
1436 | fds = fd->next; |
1437 | jffs2_free_full_dirent(fd); |
1438 | } |
1439 | |
1440 | if (f->inocache && f->inocache->state != INO_STATE_CHECKING) { |
1441 | jffs2_set_inocache_state(c, ic: f->inocache, INO_STATE_CHECKEDABSENT); |
1442 | if (f->inocache->nodes == (void *)f->inocache) |
1443 | jffs2_del_ino_cache(c, old: f->inocache); |
1444 | } |
1445 | |
1446 | mutex_unlock(lock: &f->sem); |
1447 | } |
1448 | |