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Linux/fs/jffs2/nodelist.c

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  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/fs.h>
 17 #include <linux/mtd/mtd.h>
 18 #include <linux/rbtree.h>
 19 #include <linux/crc32.h>
 20 #include <linux/pagemap.h>
 21 #include "nodelist.h"
 22 
 23 static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
 24                                      struct jffs2_node_frag *this);
 25 
 26 void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list)
 27 {
 28         struct jffs2_full_dirent **prev = list;
 29 
 30         dbg_dentlist("add dirent \"%s\", ino #%u\n", new->name, new->ino);
 31 
 32         while ((*prev) && (*prev)->nhash <= new->nhash) {
 33                 if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name)) {
 34                         /* Duplicate. Free one */
 35                         if (new->version < (*prev)->version) {
 36                                 dbg_dentlist("Eep! Marking new dirent node obsolete, old is \"%s\", ino #%u\n",
 37                                         (*prev)->name, (*prev)->ino);
 38                                 jffs2_mark_node_obsolete(c, new->raw);
 39                                 jffs2_free_full_dirent(new);
 40                         } else {
 41                                 dbg_dentlist("marking old dirent \"%s\", ino #%u obsolete\n",
 42                                         (*prev)->name, (*prev)->ino);
 43                                 new->next = (*prev)->next;
 44                                 /* It may have been a 'placeholder' deletion dirent, 
 45                                    if jffs2_can_mark_obsolete() (see jffs2_do_unlink()) */
 46                                 if ((*prev)->raw)
 47                                         jffs2_mark_node_obsolete(c, ((*prev)->raw));
 48                                 jffs2_free_full_dirent(*prev);
 49                                 *prev = new;
 50                         }
 51                         return;
 52                 }
 53                 prev = &((*prev)->next);
 54         }
 55         new->next = *prev;
 56         *prev = new;
 57 }
 58 
 59 uint32_t jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint32_t size)
 60 {
 61         struct jffs2_node_frag *frag = jffs2_lookup_node_frag(list, size);
 62 
 63         dbg_fragtree("truncating fragtree to 0x%08x bytes\n", size);
 64 
 65         /* We know frag->ofs <= size. That's what lookup does for us */
 66         if (frag && frag->ofs != size) {
 67                 if (frag->ofs+frag->size > size) {
 68                         frag->size = size - frag->ofs;
 69                 }
 70                 frag = frag_next(frag);
 71         }
 72         while (frag && frag->ofs >= size) {
 73                 struct jffs2_node_frag *next = frag_next(frag);
 74 
 75                 frag_erase(frag, list);
 76                 jffs2_obsolete_node_frag(c, frag);
 77                 frag = next;
 78         }
 79 
 80         if (size == 0)
 81                 return 0;
 82 
 83         frag = frag_last(list);
 84 
 85         /* Sanity check for truncation to longer than we started with... */
 86         if (!frag)
 87                 return 0;
 88         if (frag->ofs + frag->size < size)
 89                 return frag->ofs + frag->size;
 90 
 91         /* If the last fragment starts at the RAM page boundary, it is
 92          * REF_PRISTINE irrespective of its size. */
 93         if (frag->node && (frag->ofs & (PAGE_SIZE - 1)) == 0) {
 94                 dbg_fragtree2("marking the last fragment 0x%08x-0x%08x REF_PRISTINE.\n",
 95                         frag->ofs, frag->ofs + frag->size);
 96                 frag->node->raw->flash_offset = ref_offset(frag->node->raw) | REF_PRISTINE;
 97         }
 98         return size;
 99 }
100 
101 static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
102                                      struct jffs2_node_frag *this)
103 {
104         if (this->node) {
105                 this->node->frags--;
106                 if (!this->node->frags) {
107                         /* The node has no valid frags left. It's totally obsoleted */
108                         dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) obsolete\n",
109                                 ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size);
110                         jffs2_mark_node_obsolete(c, this->node->raw);
111                         jffs2_free_full_dnode(this->node);
112                 } else {
113                         dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) REF_NORMAL. frags is %d\n",
114                                 ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size, this->node->frags);
115                         mark_ref_normal(this->node->raw);
116                 }
117 
118         }
119         jffs2_free_node_frag(this);
120 }
121 
122 static void jffs2_fragtree_insert(struct jffs2_node_frag *newfrag, struct jffs2_node_frag *base)
123 {
124         struct rb_node *parent = &base->rb;
125         struct rb_node **link = &parent;
126 
127         dbg_fragtree2("insert frag (0x%04x-0x%04x)\n", newfrag->ofs, newfrag->ofs + newfrag->size);
128 
129         while (*link) {
130                 parent = *link;
131                 base = rb_entry(parent, struct jffs2_node_frag, rb);
132 
133                 if (newfrag->ofs > base->ofs)
134                         link = &base->rb.rb_right;
135                 else if (newfrag->ofs < base->ofs)
136                         link = &base->rb.rb_left;
137                 else {
138                         JFFS2_ERROR("duplicate frag at %08x (%p,%p)\n", newfrag->ofs, newfrag, base);
139                         BUG();
140                 }
141         }
142 
143         rb_link_node(&newfrag->rb, &base->rb, link);
144 }
145 
146 /*
147  * Allocate and initializes a new fragment.
148  */
149 static struct jffs2_node_frag * new_fragment(struct jffs2_full_dnode *fn, uint32_t ofs, uint32_t size)
150 {
151         struct jffs2_node_frag *newfrag;
152 
153         newfrag = jffs2_alloc_node_frag();
154         if (likely(newfrag)) {
155                 newfrag->ofs = ofs;
156                 newfrag->size = size;
157                 newfrag->node = fn;
158         } else {
159                 JFFS2_ERROR("cannot allocate a jffs2_node_frag object\n");
160         }
161 
162         return newfrag;
163 }
164 
165 /*
166  * Called when there is no overlapping fragment exist. Inserts a hole before the new
167  * fragment and inserts the new fragment to the fragtree.
168  */
169 static int no_overlapping_node(struct jffs2_sb_info *c, struct rb_root *root,
170                                struct jffs2_node_frag *newfrag,
171                                struct jffs2_node_frag *this, uint32_t lastend)
172 {
173         if (lastend < newfrag->node->ofs) {
174                 /* put a hole in before the new fragment */
175                 struct jffs2_node_frag *holefrag;
176 
177                 holefrag= new_fragment(NULL, lastend, newfrag->node->ofs - lastend);
178                 if (unlikely(!holefrag)) {
179                         jffs2_free_node_frag(newfrag);
180                         return -ENOMEM;
181                 }
182 
183                 if (this) {
184                         /* By definition, the 'this' node has no right-hand child,
185                            because there are no frags with offset greater than it.
186                            So that's where we want to put the hole */
187                         dbg_fragtree2("add hole frag %#04x-%#04x on the right of the new frag.\n",
188                                 holefrag->ofs, holefrag->ofs + holefrag->size);
189                         rb_link_node(&holefrag->rb, &this->rb, &this->rb.rb_right);
190                 } else {
191                         dbg_fragtree2("Add hole frag %#04x-%#04x to the root of the tree.\n",
192                                 holefrag->ofs, holefrag->ofs + holefrag->size);
193                         rb_link_node(&holefrag->rb, NULL, &root->rb_node);
194                 }
195                 rb_insert_color(&holefrag->rb, root);
196                 this = holefrag;
197         }
198 
199         if (this) {
200                 /* By definition, the 'this' node has no right-hand child,
201                    because there are no frags with offset greater than it.
202                    So that's where we want to put new fragment */
203                 dbg_fragtree2("add the new node at the right\n");
204                 rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right);
205         } else {
206                 dbg_fragtree2("insert the new node at the root of the tree\n");
207                 rb_link_node(&newfrag->rb, NULL, &root->rb_node);
208         }
209         rb_insert_color(&newfrag->rb, root);
210 
211         return 0;
212 }
213 
214 /* Doesn't set inode->i_size */
215 static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *root, struct jffs2_node_frag *newfrag)
216 {
217         struct jffs2_node_frag *this;
218         uint32_t lastend;
219 
220         /* Skip all the nodes which are completed before this one starts */
221         this = jffs2_lookup_node_frag(root, newfrag->node->ofs);
222 
223         if (this) {
224                 dbg_fragtree2("lookup gave frag 0x%04x-0x%04x; phys 0x%08x (*%p)\n",
225                           this->ofs, this->ofs+this->size, this->node?(ref_offset(this->node->raw)):0xffffffff, this);
226                 lastend = this->ofs + this->size;
227         } else {
228                 dbg_fragtree2("lookup gave no frag\n");
229                 lastend = 0;
230         }
231 
232         /* See if we ran off the end of the fragtree */
233         if (lastend <= newfrag->ofs) {
234                 /* We did */
235 
236                 /* Check if 'this' node was on the same page as the new node.
237                    If so, both 'this' and the new node get marked REF_NORMAL so
238                    the GC can take a look.
239                 */
240                 if (lastend && (lastend-1) >> PAGE_SHIFT == newfrag->ofs >> PAGE_SHIFT) {
241                         if (this->node)
242                                 mark_ref_normal(this->node->raw);
243                         mark_ref_normal(newfrag->node->raw);
244                 }
245 
246                 return no_overlapping_node(c, root, newfrag, this, lastend);
247         }
248 
249         if (this->node)
250                 dbg_fragtree2("dealing with frag %u-%u, phys %#08x(%d).\n",
251                 this->ofs, this->ofs + this->size,
252                 ref_offset(this->node->raw), ref_flags(this->node->raw));
253         else
254                 dbg_fragtree2("dealing with hole frag %u-%u.\n",
255                 this->ofs, this->ofs + this->size);
256 
257         /* OK. 'this' is pointing at the first frag that newfrag->ofs at least partially obsoletes,
258          * - i.e. newfrag->ofs < this->ofs+this->size && newfrag->ofs >= this->ofs
259          */
260         if (newfrag->ofs > this->ofs) {
261                 /* This node isn't completely obsoleted. The start of it remains valid */
262 
263                 /* Mark the new node and the partially covered node REF_NORMAL -- let
264                    the GC take a look at them */
265                 mark_ref_normal(newfrag->node->raw);
266                 if (this->node)
267                         mark_ref_normal(this->node->raw);
268 
269                 if (this->ofs + this->size > newfrag->ofs + newfrag->size) {
270                         /* The new node splits 'this' frag into two */
271                         struct jffs2_node_frag *newfrag2;
272 
273                         if (this->node)
274                                 dbg_fragtree2("split old frag 0x%04x-0x%04x, phys 0x%08x\n",
275                                         this->ofs, this->ofs+this->size, ref_offset(this->node->raw));
276                         else
277                                 dbg_fragtree2("split old hole frag 0x%04x-0x%04x\n",
278                                         this->ofs, this->ofs+this->size);
279 
280                         /* New second frag pointing to this's node */
281                         newfrag2 = new_fragment(this->node, newfrag->ofs + newfrag->size,
282                                                 this->ofs + this->size - newfrag->ofs - newfrag->size);
283                         if (unlikely(!newfrag2))
284                                 return -ENOMEM;
285                         if (this->node)
286                                 this->node->frags++;
287 
288                         /* Adjust size of original 'this' */
289                         this->size = newfrag->ofs - this->ofs;
290 
291                         /* Now, we know there's no node with offset
292                            greater than this->ofs but smaller than
293                            newfrag2->ofs or newfrag->ofs, for obvious
294                            reasons. So we can do a tree insert from
295                            'this' to insert newfrag, and a tree insert
296                            from newfrag to insert newfrag2. */
297                         jffs2_fragtree_insert(newfrag, this);
298                         rb_insert_color(&newfrag->rb, root);
299 
300                         jffs2_fragtree_insert(newfrag2, newfrag);
301                         rb_insert_color(&newfrag2->rb, root);
302 
303                         return 0;
304                 }
305                 /* New node just reduces 'this' frag in size, doesn't split it */
306                 this->size = newfrag->ofs - this->ofs;
307 
308                 /* Again, we know it lives down here in the tree */
309                 jffs2_fragtree_insert(newfrag, this);
310                 rb_insert_color(&newfrag->rb, root);
311         } else {
312                 /* New frag starts at the same point as 'this' used to. Replace
313                    it in the tree without doing a delete and insertion */
314                 dbg_fragtree2("inserting newfrag (*%p),%d-%d in before 'this' (*%p),%d-%d\n",
315                           newfrag, newfrag->ofs, newfrag->ofs+newfrag->size, this, this->ofs, this->ofs+this->size);
316 
317                 rb_replace_node(&this->rb, &newfrag->rb, root);
318 
319                 if (newfrag->ofs + newfrag->size >= this->ofs+this->size) {
320                         dbg_fragtree2("obsoleting node frag %p (%x-%x)\n", this, this->ofs, this->ofs+this->size);
321                         jffs2_obsolete_node_frag(c, this);
322                 } else {
323                         this->ofs += newfrag->size;
324                         this->size -= newfrag->size;
325 
326                         jffs2_fragtree_insert(this, newfrag);
327                         rb_insert_color(&this->rb, root);
328                         return 0;
329                 }
330         }
331         /* OK, now we have newfrag added in the correct place in the tree, but
332            frag_next(newfrag) may be a fragment which is overlapped by it
333         */
334         while ((this = frag_next(newfrag)) && newfrag->ofs + newfrag->size >= this->ofs + this->size) {
335                 /* 'this' frag is obsoleted completely. */
336                 dbg_fragtree2("obsoleting node frag %p (%x-%x) and removing from tree\n",
337                         this, this->ofs, this->ofs+this->size);
338                 rb_erase(&this->rb, root);
339                 jffs2_obsolete_node_frag(c, this);
340         }
341         /* Now we're pointing at the first frag which isn't totally obsoleted by
342            the new frag */
343 
344         if (!this || newfrag->ofs + newfrag->size == this->ofs)
345                 return 0;
346 
347         /* Still some overlap but we don't need to move it in the tree */
348         this->size = (this->ofs + this->size) - (newfrag->ofs + newfrag->size);
349         this->ofs = newfrag->ofs + newfrag->size;
350 
351         /* And mark them REF_NORMAL so the GC takes a look at them */
352         if (this->node)
353                 mark_ref_normal(this->node->raw);
354         mark_ref_normal(newfrag->node->raw);
355 
356         return 0;
357 }
358 
359 /*
360  * Given an inode, probably with existing tree of fragments, add the new node
361  * to the fragment tree.
362  */
363 int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn)
364 {
365         int ret;
366         struct jffs2_node_frag *newfrag;
367 
368         if (unlikely(!fn->size))
369                 return 0;
370 
371         newfrag = new_fragment(fn, fn->ofs, fn->size);
372         if (unlikely(!newfrag))
373                 return -ENOMEM;
374         newfrag->node->frags = 1;
375 
376         dbg_fragtree("adding node %#04x-%#04x @0x%08x on flash, newfrag *%p\n",
377                   fn->ofs, fn->ofs+fn->size, ref_offset(fn->raw), newfrag);
378 
379         ret = jffs2_add_frag_to_fragtree(c, &f->fragtree, newfrag);
380         if (unlikely(ret))
381                 return ret;
382 
383         /* If we now share a page with other nodes, mark either previous
384            or next node REF_NORMAL, as appropriate.  */
385         if (newfrag->ofs & (PAGE_SIZE-1)) {
386                 struct jffs2_node_frag *prev = frag_prev(newfrag);
387 
388                 mark_ref_normal(fn->raw);
389                 /* If we don't start at zero there's _always_ a previous */
390                 if (prev->node)
391                         mark_ref_normal(prev->node->raw);
392         }
393 
394         if ((newfrag->ofs+newfrag->size) & (PAGE_SIZE-1)) {
395                 struct jffs2_node_frag *next = frag_next(newfrag);
396 
397                 if (next) {
398                         mark_ref_normal(fn->raw);
399                         if (next->node)
400                                 mark_ref_normal(next->node->raw);
401                 }
402         }
403         jffs2_dbg_fragtree_paranoia_check_nolock(f);
404 
405         return 0;
406 }
407 
408 void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state)
409 {
410         spin_lock(&c->inocache_lock);
411         ic->state = state;
412         wake_up(&c->inocache_wq);
413         spin_unlock(&c->inocache_lock);
414 }
415 
416 /* During mount, this needs no locking. During normal operation, its
417    callers want to do other stuff while still holding the inocache_lock.
418    Rather than introducing special case get_ino_cache functions or
419    callbacks, we just let the caller do the locking itself. */
420 
421 struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
422 {
423         struct jffs2_inode_cache *ret;
424 
425         ret = c->inocache_list[ino % c->inocache_hashsize];
426         while (ret && ret->ino < ino) {
427                 ret = ret->next;
428         }
429 
430         if (ret && ret->ino != ino)
431                 ret = NULL;
432 
433         return ret;
434 }
435 
436 void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new)
437 {
438         struct jffs2_inode_cache **prev;
439 
440         spin_lock(&c->inocache_lock);
441         if (!new->ino)
442                 new->ino = ++c->highest_ino;
443 
444         dbg_inocache("add %p (ino #%u)\n", new, new->ino);
445 
446         prev = &c->inocache_list[new->ino % c->inocache_hashsize];
447 
448         while ((*prev) && (*prev)->ino < new->ino) {
449                 prev = &(*prev)->next;
450         }
451         new->next = *prev;
452         *prev = new;
453 
454         spin_unlock(&c->inocache_lock);
455 }
456 
457 void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old)
458 {
459         struct jffs2_inode_cache **prev;
460 
461 #ifdef CONFIG_JFFS2_FS_XATTR
462         BUG_ON(old->xref);
463 #endif
464         dbg_inocache("del %p (ino #%u)\n", old, old->ino);
465         spin_lock(&c->inocache_lock);
466 
467         prev = &c->inocache_list[old->ino % c->inocache_hashsize];
468 
469         while ((*prev) && (*prev)->ino < old->ino) {
470                 prev = &(*prev)->next;
471         }
472         if ((*prev) == old) {
473                 *prev = old->next;
474         }
475 
476         /* Free it now unless it's in READING or CLEARING state, which
477            are the transitions upon read_inode() and clear_inode(). The
478            rest of the time we know nobody else is looking at it, and
479            if it's held by read_inode() or clear_inode() they'll free it
480            for themselves. */
481         if (old->state != INO_STATE_READING && old->state != INO_STATE_CLEARING)
482                 jffs2_free_inode_cache(old);
483 
484         spin_unlock(&c->inocache_lock);
485 }
486 
487 void jffs2_free_ino_caches(struct jffs2_sb_info *c)
488 {
489         int i;
490         struct jffs2_inode_cache *this, *next;
491 
492         for (i=0; i < c->inocache_hashsize; i++) {
493                 this = c->inocache_list[i];
494                 while (this) {
495                         next = this->next;
496                         jffs2_xattr_free_inode(c, this);
497                         jffs2_free_inode_cache(this);
498                         this = next;
499                 }
500                 c->inocache_list[i] = NULL;
501         }
502 }
503 
504 void jffs2_free_raw_node_refs(struct jffs2_sb_info *c)
505 {
506         int i;
507         struct jffs2_raw_node_ref *this, *next;
508 
509         for (i=0; i<c->nr_blocks; i++) {
510                 this = c->blocks[i].first_node;
511                 while (this) {
512                         if (this[REFS_PER_BLOCK].flash_offset == REF_LINK_NODE)
513                                 next = this[REFS_PER_BLOCK].next_in_ino;
514                         else
515                                 next = NULL;
516 
517                         jffs2_free_refblock(this);
518                         this = next;
519                 }
520                 c->blocks[i].first_node = c->blocks[i].last_node = NULL;
521         }
522 }
523 
524 struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset)
525 {
526         /* The common case in lookup is that there will be a node
527            which precisely matches. So we go looking for that first */
528         struct rb_node *next;
529         struct jffs2_node_frag *prev = NULL;
530         struct jffs2_node_frag *frag = NULL;
531 
532         dbg_fragtree2("root %p, offset %d\n", fragtree, offset);
533 
534         next = fragtree->rb_node;
535 
536         while(next) {
537                 frag = rb_entry(next, struct jffs2_node_frag, rb);
538 
539                 if (frag->ofs + frag->size <= offset) {
540                         /* Remember the closest smaller match on the way down */
541                         if (!prev || frag->ofs > prev->ofs)
542                                 prev = frag;
543                         next = frag->rb.rb_right;
544                 } else if (frag->ofs > offset) {
545                         next = frag->rb.rb_left;
546                 } else {
547                         return frag;
548                 }
549         }
550 
551         /* Exact match not found. Go back up looking at each parent,
552            and return the closest smaller one */
553 
554         if (prev)
555                 dbg_fragtree2("no match. Returning frag %#04x-%#04x, closest previous\n",
556                           prev->ofs, prev->ofs+prev->size);
557         else
558                 dbg_fragtree2("returning NULL, empty fragtree\n");
559 
560         return prev;
561 }
562 
563 /* Pass 'c' argument to indicate that nodes should be marked obsolete as
564    they're killed. */
565 void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c)
566 {
567         struct jffs2_node_frag *frag, *next;
568 
569         dbg_fragtree("killing\n");
570         rbtree_postorder_for_each_entry_safe(frag, next, root, rb) {
571                 if (frag->node && !(--frag->node->frags)) {
572                         /* Not a hole, and it's the final remaining frag
573                            of this node. Free the node */
574                         if (c)
575                                 jffs2_mark_node_obsolete(c, frag->node->raw);
576 
577                         jffs2_free_full_dnode(frag->node);
578                 }
579 
580                 jffs2_free_node_frag(frag);
581                 cond_resched();
582         }
583 }
584 
585 struct jffs2_raw_node_ref *jffs2_link_node_ref(struct jffs2_sb_info *c,
586                                                struct jffs2_eraseblock *jeb,
587                                                uint32_t ofs, uint32_t len,
588                                                struct jffs2_inode_cache *ic)
589 {
590         struct jffs2_raw_node_ref *ref;
591 
592         BUG_ON(!jeb->allocated_refs);
593         jeb->allocated_refs--;
594 
595         ref = jeb->last_node;
596 
597         dbg_noderef("Last node at %p is (%08x,%p)\n", ref, ref->flash_offset,
598                     ref->next_in_ino);
599 
600         while (ref->flash_offset != REF_EMPTY_NODE) {
601                 if (ref->flash_offset == REF_LINK_NODE)
602                         ref = ref->next_in_ino;
603                 else
604                         ref++;
605         }
606 
607         dbg_noderef("New ref is %p (%08x becomes %08x,%p) len 0x%x\n", ref, 
608                     ref->flash_offset, ofs, ref->next_in_ino, len);
609 
610         ref->flash_offset = ofs;
611 
612         if (!jeb->first_node) {
613                 jeb->first_node = ref;
614                 BUG_ON(ref_offset(ref) != jeb->offset);
615         } else if (unlikely(ref_offset(ref) != jeb->offset + c->sector_size - jeb->free_size)) {
616                 uint32_t last_len = ref_totlen(c, jeb, jeb->last_node);
617 
618                 JFFS2_ERROR("Adding new ref %p at (0x%08x-0x%08x) not immediately after previous (0x%08x-0x%08x)\n",
619                             ref, ref_offset(ref), ref_offset(ref)+len,
620                             ref_offset(jeb->last_node), 
621                             ref_offset(jeb->last_node)+last_len);
622                 BUG();
623         }
624         jeb->last_node = ref;
625 
626         if (ic) {
627                 ref->next_in_ino = ic->nodes;
628                 ic->nodes = ref;
629         } else {
630                 ref->next_in_ino = NULL;
631         }
632 
633         switch(ref_flags(ref)) {
634         case REF_UNCHECKED:
635                 c->unchecked_size += len;
636                 jeb->unchecked_size += len;
637                 break;
638 
639         case REF_NORMAL:
640         case REF_PRISTINE:
641                 c->used_size += len;
642                 jeb->used_size += len;
643                 break;
644 
645         case REF_OBSOLETE:
646                 c->dirty_size += len;
647                 jeb->dirty_size += len;
648                 break;
649         }
650         c->free_size -= len;
651         jeb->free_size -= len;
652 
653 #ifdef TEST_TOTLEN
654         /* Set (and test) __totlen field... for now */
655         ref->__totlen = len;
656         ref_totlen(c, jeb, ref);
657 #endif
658         return ref;
659 }
660 
661 /* No locking, no reservation of 'ref'. Do not use on a live file system */
662 int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
663                            uint32_t size)
664 {
665         if (!size)
666                 return 0;
667         if (unlikely(size > jeb->free_size)) {
668                 pr_crit("Dirty space 0x%x larger then free_size 0x%x (wasted 0x%x)\n",
669                         size, jeb->free_size, jeb->wasted_size);
670                 BUG();
671         }
672         /* REF_EMPTY_NODE is !obsolete, so that works OK */
673         if (jeb->last_node && ref_obsolete(jeb->last_node)) {
674 #ifdef TEST_TOTLEN
675                 jeb->last_node->__totlen += size;
676 #endif
677                 c->dirty_size += size;
678                 c->free_size -= size;
679                 jeb->dirty_size += size;
680                 jeb->free_size -= size;
681         } else {
682                 uint32_t ofs = jeb->offset + c->sector_size - jeb->free_size;
683                 ofs |= REF_OBSOLETE;
684 
685                 jffs2_link_node_ref(c, jeb, ofs, size, NULL);
686         }
687 
688         return 0;
689 }
690 
691 /* Calculate totlen from surrounding nodes or eraseblock */
692 static inline uint32_t __ref_totlen(struct jffs2_sb_info *c,
693                                     struct jffs2_eraseblock *jeb,
694                                     struct jffs2_raw_node_ref *ref)
695 {
696         uint32_t ref_end;
697         struct jffs2_raw_node_ref *next_ref = ref_next(ref);
698 
699         if (next_ref)
700                 ref_end = ref_offset(next_ref);
701         else {
702                 if (!jeb)
703                         jeb = &c->blocks[ref->flash_offset / c->sector_size];
704 
705                 /* Last node in block. Use free_space */
706                 if (unlikely(ref != jeb->last_node)) {
707                         pr_crit("ref %p @0x%08x is not jeb->last_node (%p @0x%08x)\n",
708                                 ref, ref_offset(ref), jeb->last_node,
709                                 jeb->last_node ?
710                                 ref_offset(jeb->last_node) : 0);
711                         BUG();
712                 }
713                 ref_end = jeb->offset + c->sector_size - jeb->free_size;
714         }
715         return ref_end - ref_offset(ref);
716 }
717 
718 uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
719                             struct jffs2_raw_node_ref *ref)
720 {
721         uint32_t ret;
722 
723         ret = __ref_totlen(c, jeb, ref);
724 
725 #ifdef TEST_TOTLEN
726         if (unlikely(ret != ref->__totlen)) {
727                 if (!jeb)
728                         jeb = &c->blocks[ref->flash_offset / c->sector_size];
729 
730                 pr_crit("Totlen for ref at %p (0x%08x-0x%08x) miscalculated as 0x%x instead of %x\n",
731                         ref, ref_offset(ref), ref_offset(ref) + ref->__totlen,
732                         ret, ref->__totlen);
733                 if (ref_next(ref)) {
734                         pr_crit("next %p (0x%08x-0x%08x)\n",
735                                 ref_next(ref), ref_offset(ref_next(ref)),
736                                 ref_offset(ref_next(ref)) + ref->__totlen);
737                 } else 
738                         pr_crit("No next ref. jeb->last_node is %p\n",
739                                 jeb->last_node);
740 
741                 pr_crit("jeb->wasted_size %x, dirty_size %x, used_size %x, free_size %x\n",
742                         jeb->wasted_size, jeb->dirty_size, jeb->used_size,
743                         jeb->free_size);
744 
745 #if defined(JFFS2_DBG_DUMPS) || defined(JFFS2_DBG_PARANOIA_CHECKS)
746                 __jffs2_dbg_dump_node_refs_nolock(c, jeb);
747 #endif
748 
749                 WARN_ON(1);
750 
751                 ret = ref->__totlen;
752         }
753 #endif /* TEST_TOTLEN */
754         return ret;
755 }
756 

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