Merge git://git.infradead.org/mtd-2.6
[linux-3.10.git] / fs / jffs2 / nodelist.c
1 /*
2  * JFFS2 -- Journalling Flash File System, Version 2.
3  *
4  * Copyright (C) 2001-2003 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  * $Id: nodelist.c,v 1.115 2005/11/07 11:14:40 gleixner Exp $
11  *
12  */
13
14 #include <linux/kernel.h>
15 #include <linux/sched.h>
16 #include <linux/fs.h>
17 #include <linux/mtd/mtd.h>
18 #include <linux/rbtree.h>
19 #include <linux/crc32.h>
20 #include <linux/slab.h>
21 #include <linux/pagemap.h>
22 #include "nodelist.h"
23
24 void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list)
25 {
26         struct jffs2_full_dirent **prev = list;
27
28         dbg_dentlist("add dirent \"%s\", ino #%u\n", new->name, new->ino);
29
30         while ((*prev) && (*prev)->nhash <= new->nhash) {
31                 if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name)) {
32                         /* Duplicate. Free one */
33                         if (new->version < (*prev)->version) {
34                                 dbg_dentlist("Eep! Marking new dirent node is obsolete, old is \"%s\", ino #%u\n",
35                                         (*prev)->name, (*prev)->ino);
36                                 jffs2_mark_node_obsolete(c, new->raw);
37                                 jffs2_free_full_dirent(new);
38                         } else {
39                                 dbg_dentlist("marking old dirent \"%s\", ino #%u bsolete\n",
40                                         (*prev)->name, (*prev)->ino);
41                                 new->next = (*prev)->next;
42                                 jffs2_mark_node_obsolete(c, ((*prev)->raw));
43                                 jffs2_free_full_dirent(*prev);
44                                 *prev = new;
45                         }
46                         return;
47                 }
48                 prev = &((*prev)->next);
49         }
50         new->next = *prev;
51         *prev = new;
52 }
53
54 void jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint32_t size)
55 {
56         struct jffs2_node_frag *frag = jffs2_lookup_node_frag(list, size);
57
58         dbg_fragtree("truncating fragtree to 0x%08x bytes\n", size);
59
60         /* We know frag->ofs <= size. That's what lookup does for us */
61         if (frag && frag->ofs != size) {
62                 if (frag->ofs+frag->size > size) {
63                         frag->size = size - frag->ofs;
64                 }
65                 frag = frag_next(frag);
66         }
67         while (frag && frag->ofs >= size) {
68                 struct jffs2_node_frag *next = frag_next(frag);
69
70                 frag_erase(frag, list);
71                 jffs2_obsolete_node_frag(c, frag);
72                 frag = next;
73         }
74
75         if (size == 0)
76                 return;
77
78         /*
79          * If the last fragment starts at the RAM page boundary, it is
80          * REF_PRISTINE irrespective of its size.
81          */
82         frag = frag_last(list);
83         if (frag->node && (frag->ofs & (PAGE_CACHE_SIZE - 1)) == 0) {
84                 dbg_fragtree2("marking the last fragment 0x%08x-0x%08x REF_PRISTINE.\n",
85                         frag->ofs, frag->ofs + frag->size);
86                 frag->node->raw->flash_offset = ref_offset(frag->node->raw) | REF_PRISTINE;
87         }
88 }
89
90 void jffs2_obsolete_node_frag(struct jffs2_sb_info *c, struct jffs2_node_frag *this)
91 {
92         if (this->node) {
93                 this->node->frags--;
94                 if (!this->node->frags) {
95                         /* The node has no valid frags left. It's totally obsoleted */
96                         dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) obsolete\n",
97                                 ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size);
98                         jffs2_mark_node_obsolete(c, this->node->raw);
99                         jffs2_free_full_dnode(this->node);
100                 } else {
101                         dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) REF_NORMAL. frags is %d\n",
102                                 ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size, this->node->frags);
103                         mark_ref_normal(this->node->raw);
104                 }
105
106         }
107         jffs2_free_node_frag(this);
108 }
109
110 static void jffs2_fragtree_insert(struct jffs2_node_frag *newfrag, struct jffs2_node_frag *base)
111 {
112         struct rb_node *parent = &base->rb;
113         struct rb_node **link = &parent;
114
115         dbg_fragtree2("insert frag (0x%04x-0x%04x)\n", newfrag->ofs, newfrag->ofs + newfrag->size);
116
117         while (*link) {
118                 parent = *link;
119                 base = rb_entry(parent, struct jffs2_node_frag, rb);
120
121                 if (newfrag->ofs > base->ofs)
122                         link = &base->rb.rb_right;
123                 else if (newfrag->ofs < base->ofs)
124                         link = &base->rb.rb_left;
125                 else {
126                         JFFS2_ERROR("duplicate frag at %08x (%p,%p)\n", newfrag->ofs, newfrag, base);
127                         BUG();
128                 }
129         }
130
131         rb_link_node(&newfrag->rb, &base->rb, link);
132 }
133
134 /*
135  * Allocate and initializes a new fragment.
136  */
137 static struct jffs2_node_frag * new_fragment(struct jffs2_full_dnode *fn, uint32_t ofs, uint32_t size)
138 {
139         struct jffs2_node_frag *newfrag;
140
141         newfrag = jffs2_alloc_node_frag();
142         if (likely(newfrag)) {
143                 newfrag->ofs = ofs;
144                 newfrag->size = size;
145                 newfrag->node = fn;
146         } else {
147                 JFFS2_ERROR("cannot allocate a jffs2_node_frag object\n");
148         }
149
150         return newfrag;
151 }
152
153 /*
154  * Called when there is no overlapping fragment exist. Inserts a hole before the new
155  * fragment and inserts the new fragment to the fragtree.
156  */
157 static int no_overlapping_node(struct jffs2_sb_info *c, struct rb_root *root,
158                                struct jffs2_node_frag *newfrag,
159                                struct jffs2_node_frag *this, uint32_t lastend)
160 {
161         if (lastend < newfrag->node->ofs) {
162                 /* put a hole in before the new fragment */
163                 struct jffs2_node_frag *holefrag;
164
165                 holefrag= new_fragment(NULL, lastend, newfrag->node->ofs - lastend);
166                 if (unlikely(!holefrag)) {
167                         jffs2_free_node_frag(newfrag);
168                         return -ENOMEM;
169                 }
170
171                 if (this) {
172                         /* By definition, the 'this' node has no right-hand child,
173                            because there are no frags with offset greater than it.
174                            So that's where we want to put the hole */
175                         dbg_fragtree2("add hole frag %#04x-%#04x on the right of the new frag.\n",
176                                 holefrag->ofs, holefrag->ofs + holefrag->size);
177                         rb_link_node(&holefrag->rb, &this->rb, &this->rb.rb_right);
178                 } else {
179                         dbg_fragtree2("Add hole frag %#04x-%#04x to the root of the tree.\n",
180                                 holefrag->ofs, holefrag->ofs + holefrag->size);
181                         rb_link_node(&holefrag->rb, NULL, &root->rb_node);
182                 }
183                 rb_insert_color(&holefrag->rb, root);
184                 this = holefrag;
185         }
186
187         if (this) {
188                 /* By definition, the 'this' node has no right-hand child,
189                    because there are no frags with offset greater than it.
190                    So that's where we want to put new fragment */
191                 dbg_fragtree2("add the new node at the right\n");
192                 rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right);
193         } else {
194                 dbg_fragtree2("insert the new node at the root of the tree\n");
195                 rb_link_node(&newfrag->rb, NULL, &root->rb_node);
196         }
197         rb_insert_color(&newfrag->rb, root);
198
199         return 0;
200 }
201
202 /* Doesn't set inode->i_size */
203 static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *root, struct jffs2_node_frag *newfrag)
204 {
205         struct jffs2_node_frag *this;
206         uint32_t lastend;
207
208         /* Skip all the nodes which are completed before this one starts */
209         this = jffs2_lookup_node_frag(root, newfrag->node->ofs);
210
211         if (this) {
212                 dbg_fragtree2("lookup gave frag 0x%04x-0x%04x; phys 0x%08x (*%p)\n",
213                           this->ofs, this->ofs+this->size, this->node?(ref_offset(this->node->raw)):0xffffffff, this);
214                 lastend = this->ofs + this->size;
215         } else {
216                 dbg_fragtree2("lookup gave no frag\n");
217                 lastend = 0;
218         }
219
220         /* See if we ran off the end of the fragtree */
221         if (lastend <= newfrag->ofs) {
222                 /* We did */
223
224                 /* Check if 'this' node was on the same page as the new node.
225                    If so, both 'this' and the new node get marked REF_NORMAL so
226                    the GC can take a look.
227                 */
228                 if (lastend && (lastend-1) >> PAGE_CACHE_SHIFT == newfrag->ofs >> PAGE_CACHE_SHIFT) {
229                         if (this->node)
230                                 mark_ref_normal(this->node->raw);
231                         mark_ref_normal(newfrag->node->raw);
232                 }
233
234                 return no_overlapping_node(c, root, newfrag, this, lastend);
235         }
236
237         if (this->node)
238                 dbg_fragtree2("dealing with frag %u-%u, phys %#08x(%d).\n",
239                 this->ofs, this->ofs + this->size,
240                 ref_offset(this->node->raw), ref_flags(this->node->raw));
241         else
242                 dbg_fragtree2("dealing with hole frag %u-%u.\n",
243                 this->ofs, this->ofs + this->size);
244
245         /* OK. 'this' is pointing at the first frag that newfrag->ofs at least partially obsoletes,
246          * - i.e. newfrag->ofs < this->ofs+this->size && newfrag->ofs >= this->ofs
247          */
248         if (newfrag->ofs > this->ofs) {
249                 /* This node isn't completely obsoleted. The start of it remains valid */
250
251                 /* Mark the new node and the partially covered node REF_NORMAL -- let
252                    the GC take a look at them */
253                 mark_ref_normal(newfrag->node->raw);
254                 if (this->node)
255                         mark_ref_normal(this->node->raw);
256
257                 if (this->ofs + this->size > newfrag->ofs + newfrag->size) {
258                         /* The new node splits 'this' frag into two */
259                         struct jffs2_node_frag *newfrag2;
260
261                         if (this->node)
262                                 dbg_fragtree2("split old frag 0x%04x-0x%04x, phys 0x%08x\n",
263                                         this->ofs, this->ofs+this->size, ref_offset(this->node->raw));
264                         else
265                                 dbg_fragtree2("split old hole frag 0x%04x-0x%04x\n",
266                                         this->ofs, this->ofs+this->size);
267
268                         /* New second frag pointing to this's node */
269                         newfrag2 = new_fragment(this->node, newfrag->ofs + newfrag->size,
270                                                 this->ofs + this->size - newfrag->ofs - newfrag->size);
271                         if (unlikely(!newfrag2))
272                                 return -ENOMEM;
273                         if (this->node)
274                                 this->node->frags++;
275
276                         /* Adjust size of original 'this' */
277                         this->size = newfrag->ofs - this->ofs;
278
279                         /* Now, we know there's no node with offset
280                            greater than this->ofs but smaller than
281                            newfrag2->ofs or newfrag->ofs, for obvious
282                            reasons. So we can do a tree insert from
283                            'this' to insert newfrag, and a tree insert
284                            from newfrag to insert newfrag2. */
285                         jffs2_fragtree_insert(newfrag, this);
286                         rb_insert_color(&newfrag->rb, root);
287
288                         jffs2_fragtree_insert(newfrag2, newfrag);
289                         rb_insert_color(&newfrag2->rb, root);
290
291                         return 0;
292                 }
293                 /* New node just reduces 'this' frag in size, doesn't split it */
294                 this->size = newfrag->ofs - this->ofs;
295
296                 /* Again, we know it lives down here in the tree */
297                 jffs2_fragtree_insert(newfrag, this);
298                 rb_insert_color(&newfrag->rb, root);
299         } else {
300                 /* New frag starts at the same point as 'this' used to. Replace
301                    it in the tree without doing a delete and insertion */
302                 dbg_fragtree2("inserting newfrag (*%p),%d-%d in before 'this' (*%p),%d-%d\n",
303                           newfrag, newfrag->ofs, newfrag->ofs+newfrag->size, this, this->ofs, this->ofs+this->size);
304
305                 rb_replace_node(&this->rb, &newfrag->rb, root);
306
307                 if (newfrag->ofs + newfrag->size >= this->ofs+this->size) {
308                         dbg_fragtree2("obsoleting node frag %p (%x-%x)\n", this, this->ofs, this->ofs+this->size);
309                         jffs2_obsolete_node_frag(c, this);
310                 } else {
311                         this->ofs += newfrag->size;
312                         this->size -= newfrag->size;
313
314                         jffs2_fragtree_insert(this, newfrag);
315                         rb_insert_color(&this->rb, root);
316                         return 0;
317                 }
318         }
319         /* OK, now we have newfrag added in the correct place in the tree, but
320            frag_next(newfrag) may be a fragment which is overlapped by it
321         */
322         while ((this = frag_next(newfrag)) && newfrag->ofs + newfrag->size >= this->ofs + this->size) {
323                 /* 'this' frag is obsoleted completely. */
324                 dbg_fragtree2("obsoleting node frag %p (%x-%x) and removing from tree\n",
325                         this, this->ofs, this->ofs+this->size);
326                 rb_erase(&this->rb, root);
327                 jffs2_obsolete_node_frag(c, this);
328         }
329         /* Now we're pointing at the first frag which isn't totally obsoleted by
330            the new frag */
331
332         if (!this || newfrag->ofs + newfrag->size == this->ofs)
333                 return 0;
334
335         /* Still some overlap but we don't need to move it in the tree */
336         this->size = (this->ofs + this->size) - (newfrag->ofs + newfrag->size);
337         this->ofs = newfrag->ofs + newfrag->size;
338
339         /* And mark them REF_NORMAL so the GC takes a look at them */
340         if (this->node)
341                 mark_ref_normal(this->node->raw);
342         mark_ref_normal(newfrag->node->raw);
343
344         return 0;
345 }
346
347 /*
348  * Given an inode, probably with existing tree of fragments, add the new node
349  * to the fragment tree.
350  */
351 int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn)
352 {
353         int ret;
354         struct jffs2_node_frag *newfrag;
355
356         if (unlikely(!fn->size))
357                 return 0;
358
359         newfrag = new_fragment(fn, fn->ofs, fn->size);
360         if (unlikely(!newfrag))
361                 return -ENOMEM;
362         newfrag->node->frags = 1;
363
364         dbg_fragtree("adding node %#04x-%#04x @0x%08x on flash, newfrag *%p\n",
365                   fn->ofs, fn->ofs+fn->size, ref_offset(fn->raw), newfrag);
366
367         ret = jffs2_add_frag_to_fragtree(c, &f->fragtree, newfrag);
368         if (unlikely(ret))
369                 return ret;
370
371         /* If we now share a page with other nodes, mark either previous
372            or next node REF_NORMAL, as appropriate.  */
373         if (newfrag->ofs & (PAGE_CACHE_SIZE-1)) {
374                 struct jffs2_node_frag *prev = frag_prev(newfrag);
375
376                 mark_ref_normal(fn->raw);
377                 /* If we don't start at zero there's _always_ a previous */
378                 if (prev->node)
379                         mark_ref_normal(prev->node->raw);
380         }
381
382         if ((newfrag->ofs+newfrag->size) & (PAGE_CACHE_SIZE-1)) {
383                 struct jffs2_node_frag *next = frag_next(newfrag);
384
385                 if (next) {
386                         mark_ref_normal(fn->raw);
387                         if (next->node)
388                                 mark_ref_normal(next->node->raw);
389                 }
390         }
391         jffs2_dbg_fragtree_paranoia_check_nolock(f);
392
393         return 0;
394 }
395
396 /*
397  * Check the data CRC of the node.
398  *
399  * Returns: 0 if the data CRC is correct;
400  *          1 - if incorrect;
401  *          error code if an error occured.
402  */
403 static int check_node_data(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn)
404 {
405         struct jffs2_raw_node_ref *ref = tn->fn->raw;
406         int err = 0, pointed = 0;
407         struct jffs2_eraseblock *jeb;
408         unsigned char *buffer;
409         uint32_t crc, ofs, len;
410         size_t retlen;
411
412         BUG_ON(tn->csize == 0);
413
414         if (!jffs2_is_writebuffered(c))
415                 goto adj_acc;
416
417         /* Calculate how many bytes were already checked */
418         ofs = ref_offset(ref) + sizeof(struct jffs2_raw_inode);
419         len = ofs % c->wbuf_pagesize;
420         if (likely(len))
421                 len = c->wbuf_pagesize - len;
422
423         if (len >= tn->csize) {
424                 dbg_readinode("no need to check node at %#08x, data length %u, data starts at %#08x - it has already been checked.\n",
425                         ref_offset(ref), tn->csize, ofs);
426                 goto adj_acc;
427         }
428
429         ofs += len;
430         len = tn->csize - len;
431
432         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",
433                 ref_offset(ref), tn->csize, tn->partial_crc, tn->data_crc, ofs - len, ofs, len);
434
435 #ifndef __ECOS
436         /* TODO: instead, incapsulate point() stuff to jffs2_flash_read(),
437          * adding and jffs2_flash_read_end() interface. */
438         if (c->mtd->point) {
439                 err = c->mtd->point(c->mtd, ofs, len, &retlen, &buffer);
440                 if (!err && retlen < tn->csize) {
441                         JFFS2_WARNING("MTD point returned len too short: %zu instead of %u.\n", retlen, tn->csize);
442                         c->mtd->unpoint(c->mtd, buffer, ofs, len);
443                 } else if (err)
444                         JFFS2_WARNING("MTD point failed: error code %d.\n", err);
445                 else
446                         pointed = 1; /* succefully pointed to device */
447         }
448 #endif
449
450         if (!pointed) {
451                 buffer = kmalloc(len, GFP_KERNEL);
452                 if (unlikely(!buffer))
453                         return -ENOMEM;
454
455                 /* TODO: this is very frequent pattern, make it a separate
456                  * routine */
457                 err = jffs2_flash_read(c, ofs, len, &retlen, buffer);
458                 if (err) {
459                         JFFS2_ERROR("can not read %d bytes from 0x%08x, error code: %d.\n", len, ofs, err);
460                         goto free_out;
461                 }
462
463                 if (retlen != len) {
464                         JFFS2_ERROR("short read at %#08x: %zd instead of %d.\n", ofs, retlen, len);
465                         err = -EIO;
466                         goto free_out;
467                 }
468         }
469
470         /* Continue calculating CRC */
471         crc = crc32(tn->partial_crc, buffer, len);
472         if(!pointed)
473                 kfree(buffer);
474 #ifndef __ECOS
475         else
476                 c->mtd->unpoint(c->mtd, buffer, ofs, len);
477 #endif
478
479         if (crc != tn->data_crc) {
480                 JFFS2_NOTICE("wrong data CRC in data node at 0x%08x: read %#08x, calculated %#08x.\n",
481                         ofs, tn->data_crc, crc);
482                 return 1;
483         }
484
485 adj_acc:
486         jeb = &c->blocks[ref->flash_offset / c->sector_size];
487         len = ref_totlen(c, jeb, ref);
488
489         /*
490          * Mark the node as having been checked and fix the
491          * accounting accordingly.
492          */
493         spin_lock(&c->erase_completion_lock);
494         jeb->used_size += len;
495         jeb->unchecked_size -= len;
496         c->used_size += len;
497         c->unchecked_size -= len;
498         spin_unlock(&c->erase_completion_lock);
499
500         return 0;
501
502 free_out:
503         if(!pointed)
504                 kfree(buffer);
505 #ifndef __ECOS
506         else
507                 c->mtd->unpoint(c->mtd, buffer, ofs, len);
508 #endif
509         return err;
510 }
511
512 /*
513  * Helper function for jffs2_add_older_frag_to_fragtree().
514  *
515  * Checks the node if we are in the checking stage.
516  */
517 static int check_node(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_tmp_dnode_info *tn)
518 {
519         int ret;
520
521         BUG_ON(ref_obsolete(tn->fn->raw));
522
523         /* We only check the data CRC of unchecked nodes */
524         if (ref_flags(tn->fn->raw) != REF_UNCHECKED)
525                 return 0;
526
527         dbg_fragtree2("check node %#04x-%#04x, phys offs %#08x.\n",
528                 tn->fn->ofs, tn->fn->ofs + tn->fn->size, ref_offset(tn->fn->raw));
529
530         ret = check_node_data(c, tn);
531         if (unlikely(ret < 0)) {
532                 JFFS2_ERROR("check_node_data() returned error: %d.\n",
533                         ret);
534         } else if (unlikely(ret > 0)) {
535                 dbg_fragtree2("CRC error, mark it obsolete.\n");
536                 jffs2_mark_node_obsolete(c, tn->fn->raw);
537         }
538
539         return ret;
540 }
541
542 /*
543  * Helper function for jffs2_add_older_frag_to_fragtree().
544  *
545  * Called when the new fragment that is being inserted
546  * splits a hole fragment.
547  */
548 static int split_hole(struct jffs2_sb_info *c, struct rb_root *root,
549                       struct jffs2_node_frag *newfrag, struct jffs2_node_frag *hole)
550 {
551         dbg_fragtree2("fragment %#04x-%#04x splits the hole %#04x-%#04x\n",
552                 newfrag->ofs, newfrag->ofs + newfrag->size, hole->ofs, hole->ofs + hole->size);
553
554         if (hole->ofs == newfrag->ofs) {
555                 /*
556                  * Well, the new fragment actually starts at the same offset as
557                  * the hole.
558                  */
559                 if (hole->ofs + hole->size > newfrag->ofs + newfrag->size) {
560                         /*
561                          * We replace the overlapped left part of the hole by
562                          * the new node.
563                          */
564
565                         dbg_fragtree2("insert fragment %#04x-%#04x and cut the left part of the hole\n",
566                                 newfrag->ofs, newfrag->ofs + newfrag->size);
567                         rb_replace_node(&hole->rb, &newfrag->rb, root);
568
569                         hole->ofs += newfrag->size;
570                         hole->size -= newfrag->size;
571
572                         /*
573                          * We know that 'hole' should be the right hand
574                          * fragment.
575                          */
576                         jffs2_fragtree_insert(hole, newfrag);
577                         rb_insert_color(&hole->rb, root);
578                 } else {
579                         /*
580                          * Ah, the new fragment is of the same size as the hole.
581                          * Relace the hole by it.
582                          */
583                         dbg_fragtree2("insert fragment %#04x-%#04x and overwrite hole\n",
584                                 newfrag->ofs, newfrag->ofs + newfrag->size);
585                         rb_replace_node(&hole->rb, &newfrag->rb, root);
586                         jffs2_free_node_frag(hole);
587                 }
588         } else {
589                 /* The new fragment lefts some hole space at the left */
590
591                 struct jffs2_node_frag * newfrag2 = NULL;
592
593                 if (hole->ofs + hole->size > newfrag->ofs + newfrag->size) {
594                         /* The new frag also lefts some space at the right */
595                         newfrag2 = new_fragment(NULL, newfrag->ofs +
596                                 newfrag->size, hole->ofs + hole->size
597                                 - newfrag->ofs - newfrag->size);
598                         if (unlikely(!newfrag2)) {
599                                 jffs2_free_node_frag(newfrag);
600                                 return -ENOMEM;
601                         }
602                 }
603
604                 hole->size = newfrag->ofs - hole->ofs;
605                 dbg_fragtree2("left the hole %#04x-%#04x at the left and inserd fragment %#04x-%#04x\n",
606                         hole->ofs, hole->ofs + hole->size, newfrag->ofs, newfrag->ofs + newfrag->size);
607
608                 jffs2_fragtree_insert(newfrag, hole);
609                 rb_insert_color(&newfrag->rb, root);
610
611                 if (newfrag2) {
612                         dbg_fragtree2("left the hole %#04x-%#04x at the right\n",
613                                 newfrag2->ofs, newfrag2->ofs + newfrag2->size);
614                         jffs2_fragtree_insert(newfrag2, newfrag);
615                         rb_insert_color(&newfrag2->rb, root);
616                 }
617         }
618
619         return 0;
620 }
621
622 /*
623  * This function is used when we build inode. It expects the nodes are passed
624  * in the decreasing version order. The whole point of this is to improve the
625  * inodes checking on NAND: we check the nodes' data CRC only when they are not
626  * obsoleted. Previously, add_frag_to_fragtree() function was used and
627  * nodes were passed to it in the increasing version ordes and CRCs of all
628  * nodes were checked.
629  *
630  * Note: tn->fn->size shouldn't be zero.
631  *
632  * Returns 0 if the node was inserted
633  *         1 if it wasn't inserted (since it is obsolete)
634  *         < 0 an if error occured
635  */
636 int jffs2_add_older_frag_to_fragtree(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
637                                      struct jffs2_tmp_dnode_info *tn)
638 {
639         struct jffs2_node_frag *this, *newfrag;
640         uint32_t lastend;
641         struct jffs2_full_dnode *fn = tn->fn;
642         struct rb_root *root = &f->fragtree;
643         uint32_t fn_size = fn->size, fn_ofs = fn->ofs;
644         int err, checked = 0;
645         int ref_flag;
646
647         dbg_fragtree("insert fragment %#04x-%#04x, ver %u\n", fn_ofs, fn_ofs + fn_size, tn->version);
648
649         /* Skip all the nodes which are completed before this one starts */
650         this = jffs2_lookup_node_frag(root, fn_ofs);
651         if (this)
652                 dbg_fragtree2("'this' found %#04x-%#04x (%s)\n", this->ofs, this->ofs + this->size, this->node ? "data" : "hole");
653
654         if (this)
655                 lastend = this->ofs + this->size;
656         else
657                 lastend = 0;
658
659         /* Detect the preliminary type of node */
660         if (fn->size >= PAGE_CACHE_SIZE)
661                 ref_flag = REF_PRISTINE;
662         else
663                 ref_flag = REF_NORMAL;
664
665         /* See if we ran off the end of the root */
666         if (lastend <= fn_ofs) {
667                 /* We did */
668
669                 /*
670                  * We are going to insert the new node into the
671                  * fragment tree, so check it.
672                  */
673                 err = check_node(c, f, tn);
674                 if (err != 0)
675                         return err;
676
677                 fn->frags = 1;
678
679                 newfrag = new_fragment(fn, fn_ofs, fn_size);
680                 if (unlikely(!newfrag))
681                         return -ENOMEM;
682
683                 err = no_overlapping_node(c, root, newfrag, this, lastend);
684                 if (unlikely(err != 0)) {
685                         jffs2_free_node_frag(newfrag);
686                         return err;
687                 }
688
689                 goto out_ok;
690         }
691
692         fn->frags = 0;
693
694         while (1) {
695                 /*
696                  * Here we have:
697                  * fn_ofs < this->ofs + this->size && fn_ofs >= this->ofs.
698                  *
699                  * Remember, 'this' has higher version, any non-hole node
700                  * which is already in the fragtree is newer then the newly
701                  * inserted.
702                  */
703                 if (!this->node) {
704                         /*
705                          * 'this' is the hole fragment, so at least the
706                          * beginning of the new fragment is valid.
707                          */
708
709                         /*
710                          * We are going to insert the new node into the
711                          * fragment tree, so check it.
712                          */
713                         if (!checked) {
714                                 err = check_node(c, f, tn);
715                                 if (unlikely(err != 0))
716                                         return err;
717                                 checked = 1;
718                         }
719
720                         if (this->ofs + this->size >= fn_ofs + fn_size) {
721                                 /* We split the hole on two parts */
722
723                                 fn->frags += 1;
724                                 newfrag = new_fragment(fn, fn_ofs, fn_size);
725                                 if (unlikely(!newfrag))
726                                         return -ENOMEM;
727
728                                 err = split_hole(c, root, newfrag, this);
729                                 if (unlikely(err))
730                                         return err;
731                                 goto out_ok;
732                         }
733
734                         /*
735                          * The beginning of the new fragment is valid since it
736                          * overlaps the hole node.
737                          */
738
739                         ref_flag = REF_NORMAL;
740
741                         fn->frags += 1;
742                         newfrag = new_fragment(fn, fn_ofs,
743                                         this->ofs + this->size - fn_ofs);
744                         if (unlikely(!newfrag))
745                                 return -ENOMEM;
746
747                         if (fn_ofs == this->ofs) {
748                                 /*
749                                  * The new node starts at the same offset as
750                                  * the hole and supersieds the hole.
751                                  */
752                                 dbg_fragtree2("add the new fragment instead of hole %#04x-%#04x, refcnt %d\n",
753                                         fn_ofs, fn_ofs + this->ofs + this->size - fn_ofs, fn->frags);
754
755                                 rb_replace_node(&this->rb, &newfrag->rb, root);
756                                 jffs2_free_node_frag(this);
757                         } else {
758                                 /*
759                                  * The hole becomes shorter as its right part
760                                  * is supersieded by the new fragment.
761                                  */
762                                 dbg_fragtree2("reduce size of hole %#04x-%#04x to %#04x-%#04x\n",
763                                         this->ofs, this->ofs + this->size, this->ofs, this->ofs + this->size - newfrag->size);
764
765                                 dbg_fragtree2("add new fragment %#04x-%#04x, refcnt %d\n", fn_ofs,
766                                         fn_ofs + this->ofs + this->size - fn_ofs, fn->frags);
767
768                                 this->size -= newfrag->size;
769                                 jffs2_fragtree_insert(newfrag, this);
770                                 rb_insert_color(&newfrag->rb, root);
771                         }
772
773                         fn_ofs += newfrag->size;
774                         fn_size -= newfrag->size;
775                         this = rb_entry(rb_next(&newfrag->rb),
776                                         struct jffs2_node_frag, rb);
777
778                         dbg_fragtree2("switch to the next 'this' fragment: %#04x-%#04x %s\n",
779                                 this->ofs, this->ofs + this->size, this->node ? "(data)" : "(hole)");
780                 }
781
782                 /*
783                  * 'This' node is not the hole so it obsoletes the new fragment
784                  * either fully or partially.
785                  */
786                 if (this->ofs + this->size >= fn_ofs + fn_size) {
787                         /* The new node is obsolete, drop it */
788                         if (fn->frags == 0) {
789                                 dbg_fragtree2("%#04x-%#04x is obsolete, mark it obsolete\n", fn_ofs, fn_ofs + fn_size);
790                                 ref_flag = REF_OBSOLETE;
791                         }
792                         goto out_ok;
793                 } else {
794                         struct jffs2_node_frag *new_this;
795
796                         /* 'This' node obsoletes the beginning of the new node */
797                         dbg_fragtree2("the beginning %#04x-%#04x is obsolete\n", fn_ofs, this->ofs + this->size);
798
799                         ref_flag = REF_NORMAL;
800
801                         fn_size -= this->ofs + this->size - fn_ofs;
802                         fn_ofs = this->ofs + this->size;
803                         dbg_fragtree2("now considering %#04x-%#04x\n", fn_ofs, fn_ofs + fn_size);
804
805                         new_this = rb_entry(rb_next(&this->rb), struct jffs2_node_frag, rb);
806                         if (!new_this) {
807                                 /*
808                                  * There is no next fragment. Add the rest of
809                                  * the new node as the right-hand child.
810                                  */
811                                 if (!checked) {
812                                         err = check_node(c, f, tn);
813                                         if (unlikely(err != 0))
814                                                 return err;
815                                         checked = 1;
816                                 }
817
818                                 fn->frags += 1;
819                                 newfrag = new_fragment(fn, fn_ofs, fn_size);
820                                 if (unlikely(!newfrag))
821                                         return -ENOMEM;
822
823                                 dbg_fragtree2("there are no more fragments, insert %#04x-%#04x\n",
824                                         newfrag->ofs, newfrag->ofs + newfrag->size);
825                                 rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right);
826                                 rb_insert_color(&newfrag->rb, root);
827                                 goto out_ok;
828                         } else {
829                                 this = new_this;
830                                 dbg_fragtree2("switch to the next 'this' fragment: %#04x-%#04x %s\n",
831                                         this->ofs, this->ofs + this->size, this->node ? "(data)" : "(hole)");
832                         }
833                 }
834         }
835
836 out_ok:
837         BUG_ON(fn->size < PAGE_CACHE_SIZE && ref_flag == REF_PRISTINE);
838
839         if (ref_flag == REF_OBSOLETE) {
840                 dbg_fragtree2("the node is obsolete now\n");
841                 /* jffs2_mark_node_obsolete() will adjust space accounting */
842                 jffs2_mark_node_obsolete(c, fn->raw);
843                 return 1;
844         }
845
846         dbg_fragtree2("the node is \"%s\" now\n", ref_flag == REF_NORMAL ? "REF_NORMAL" : "REF_PRISTINE");
847
848         /* Space accounting was adjusted at check_node_data() */
849         spin_lock(&c->erase_completion_lock);
850         fn->raw->flash_offset = ref_offset(fn->raw) | ref_flag;
851         spin_unlock(&c->erase_completion_lock);
852
853         return 0;
854 }
855
856 void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state)
857 {
858         spin_lock(&c->inocache_lock);
859         ic->state = state;
860         wake_up(&c->inocache_wq);
861         spin_unlock(&c->inocache_lock);
862 }
863
864 /* During mount, this needs no locking. During normal operation, its
865    callers want to do other stuff while still holding the inocache_lock.
866    Rather than introducing special case get_ino_cache functions or
867    callbacks, we just let the caller do the locking itself. */
868
869 struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
870 {
871         struct jffs2_inode_cache *ret;
872
873         ret = c->inocache_list[ino % INOCACHE_HASHSIZE];
874         while (ret && ret->ino < ino) {
875                 ret = ret->next;
876         }
877
878         if (ret && ret->ino != ino)
879                 ret = NULL;
880
881         return ret;
882 }
883
884 void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new)
885 {
886         struct jffs2_inode_cache **prev;
887
888         spin_lock(&c->inocache_lock);
889         if (!new->ino)
890                 new->ino = ++c->highest_ino;
891
892         dbg_inocache("add %p (ino #%u)\n", new, new->ino);
893
894         prev = &c->inocache_list[new->ino % INOCACHE_HASHSIZE];
895
896         while ((*prev) && (*prev)->ino < new->ino) {
897                 prev = &(*prev)->next;
898         }
899         new->next = *prev;
900         *prev = new;
901
902         spin_unlock(&c->inocache_lock);
903 }
904
905 void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old)
906 {
907         struct jffs2_inode_cache **prev;
908
909         dbg_inocache("del %p (ino #%u)\n", old, old->ino);
910         spin_lock(&c->inocache_lock);
911
912         prev = &c->inocache_list[old->ino % INOCACHE_HASHSIZE];
913
914         while ((*prev) && (*prev)->ino < old->ino) {
915                 prev = &(*prev)->next;
916         }
917         if ((*prev) == old) {
918                 *prev = old->next;
919         }
920
921         /* Free it now unless it's in READING or CLEARING state, which
922            are the transitions upon read_inode() and clear_inode(). The
923            rest of the time we know nobody else is looking at it, and
924            if it's held by read_inode() or clear_inode() they'll free it
925            for themselves. */
926         if (old->state != INO_STATE_READING && old->state != INO_STATE_CLEARING)
927                 jffs2_free_inode_cache(old);
928
929         spin_unlock(&c->inocache_lock);
930 }
931
932 void jffs2_free_ino_caches(struct jffs2_sb_info *c)
933 {
934         int i;
935         struct jffs2_inode_cache *this, *next;
936
937         for (i=0; i<INOCACHE_HASHSIZE; i++) {
938                 this = c->inocache_list[i];
939                 while (this) {
940                         next = this->next;
941                         jffs2_xattr_free_inode(c, this);
942                         jffs2_free_inode_cache(this);
943                         this = next;
944                 }
945                 c->inocache_list[i] = NULL;
946         }
947 }
948
949 void jffs2_free_raw_node_refs(struct jffs2_sb_info *c)
950 {
951         int i;
952         struct jffs2_raw_node_ref *this, *next;
953
954         for (i=0; i<c->nr_blocks; i++) {
955                 this = c->blocks[i].first_node;
956                 while(this) {
957                         next = this->next_phys;
958                         jffs2_free_raw_node_ref(this);
959                         this = next;
960                 }
961                 c->blocks[i].first_node = c->blocks[i].last_node = NULL;
962         }
963 }
964
965 struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset)
966 {
967         /* The common case in lookup is that there will be a node
968            which precisely matches. So we go looking for that first */
969         struct rb_node *next;
970         struct jffs2_node_frag *prev = NULL;
971         struct jffs2_node_frag *frag = NULL;
972
973         dbg_fragtree2("root %p, offset %d\n", fragtree, offset);
974
975         next = fragtree->rb_node;
976
977         while(next) {
978                 frag = rb_entry(next, struct jffs2_node_frag, rb);
979
980                 if (frag->ofs + frag->size <= offset) {
981                         /* Remember the closest smaller match on the way down */
982                         if (!prev || frag->ofs > prev->ofs)
983                                 prev = frag;
984                         next = frag->rb.rb_right;
985                 } else if (frag->ofs > offset) {
986                         next = frag->rb.rb_left;
987                 } else {
988                         return frag;
989                 }
990         }
991
992         /* Exact match not found. Go back up looking at each parent,
993            and return the closest smaller one */
994
995         if (prev)
996                 dbg_fragtree2("no match. Returning frag %#04x-%#04x, closest previous\n",
997                           prev->ofs, prev->ofs+prev->size);
998         else
999                 dbg_fragtree2("returning NULL, empty fragtree\n");
1000
1001         return prev;
1002 }
1003
1004 /* Pass 'c' argument to indicate that nodes should be marked obsolete as
1005    they're killed. */
1006 void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c)
1007 {
1008         struct jffs2_node_frag *frag;
1009         struct jffs2_node_frag *parent;
1010
1011         if (!root->rb_node)
1012                 return;
1013
1014         dbg_fragtree("killing\n");
1015
1016         frag = (rb_entry(root->rb_node, struct jffs2_node_frag, rb));
1017         while(frag) {
1018                 if (frag->rb.rb_left) {
1019                         frag = frag_left(frag);
1020                         continue;
1021                 }
1022                 if (frag->rb.rb_right) {
1023                         frag = frag_right(frag);
1024                         continue;
1025                 }
1026
1027                 if (frag->node && !(--frag->node->frags)) {
1028                         /* Not a hole, and it's the final remaining frag
1029                            of this node. Free the node */
1030                         if (c)
1031                                 jffs2_mark_node_obsolete(c, frag->node->raw);
1032
1033                         jffs2_free_full_dnode(frag->node);
1034                 }
1035                 parent = frag_parent(frag);
1036                 if (parent) {
1037                         if (frag_left(parent) == frag)
1038                                 parent->rb.rb_left = NULL;
1039                         else
1040                                 parent->rb.rb_right = NULL;
1041                 }
1042
1043                 jffs2_free_node_frag(frag);
1044                 frag = parent;
1045
1046                 cond_resched();
1047         }
1048 }