fs/jffs2/nodelist.c

   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 #include <linux/kernel.h>
  13 #include <linux/sched.h>
  14 #include <linux/fs.h>
  15 #include <linux/mtd/mtd.h>
  16 #include <linux/rbtree.h>
  17 #include <linux/crc32.h>
  18 #include <linux/slab.h>
  19 #include <linux/pagemap.h>
  20 #include "nodelist.h"
  21
  22 static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
  23                                      struct jffs2_node_frag *this);
  24
  25 void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list)
  26 {
  27         struct jffs2_full_dirent **prev = list;
  28
  29         dbg_dentlist("add dirent \"%s\", ino #%u\n", new->name, new->ino);
  30
  31         while ((*prev) && (*prev)->nhash <= new->nhash) {
  32                 if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name)) {
  33                         /* Duplicate. Free one */
  34                         if (new->version < (*prev)->version) {
  35                                 dbg_dentlist("Eep! Marking new dirent node obsolete, old is \"%s\", ino #%u\n",
  36                                         (*prev)->name, (*prev)->ino);
  37                                 jffs2_mark_node_obsolete(c, new->raw);
  38                                 jffs2_free_full_dirent(new);
  39                         } else {
  40                                 dbg_dentlist("marking old dirent \"%s\", ino #%u obsolete\n",
  41                                         (*prev)->name, (*prev)->ino);
  42                                 new->next = (*prev)->next;
  43                                 /* It may have been a 'placeholder' deletion dirent,
  44                                    if jffs2_can_mark_obsolete() (see jffs2_do_unlink()) */
  45                                 if ((*prev)->raw)
  46                                         jffs2_mark_node_obsolete(c, ((*prev)->raw));
  47                                 jffs2_free_full_dirent(*prev);
  48                                 *prev = new;
  49                         }
  50                         return;
  51                 }
  52                 prev = &((*prev)->next);
  53         }
  54         new->next = *prev;
  55         *prev = new;
  56 }
  57
  58 uint32_t jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint32_t size)
  59 {
  60         struct jffs2_node_frag *frag = jffs2_lookup_node_frag(list, size);
  61
  62         dbg_fragtree("truncating fragtree to 0x%08x bytes\n", size);
  63
  64         /* We know frag->ofs <= size. That's what lookup does for us */
  65         if (frag && frag->ofs != size) {
  66                 if (frag->ofs+frag->size > size) {
  67                         frag->size = size - frag->ofs;
  68                 }
  69                 frag = frag_next(frag);
  70         }
  71         while (frag && frag->ofs >= size) {
  72                 struct jffs2_node_frag *next = frag_next(frag);
  73
  74                 frag_erase(frag, list);
  75                 jffs2_obsolete_node_frag(c, frag);
  76                 frag = next;
  77         }
  78
  79         if (size == 0)
  80                 return 0;
  81
  82         frag = frag_last(list);
  83
  84         /* Sanity check for truncation to longer than we started with... */
  85         if (!frag)
  86                 return 0;
  87         if (frag->ofs + frag->size < size)
  88                 return frag->ofs + frag->size;
  89
  90         /* If the last fragment starts at the RAM page boundary, it is
  91          * REF_PRISTINE irrespective of its size. */
  92         if (frag->node && (frag->ofs & (PAGE_CACHE_SIZE - 1)) == 0) {
  93                 dbg_fragtree2("marking the last fragment 0x%08x-0x%08x REF_PRISTINE.\n",
  94                         frag->ofs, frag->ofs + frag->size);
  95                 frag->node->raw->flash_offset = ref_offset(frag->node->raw) | REF_PRISTINE;
  96         }
  97         return size;
  98 }
  99
 100 static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
 101                                      struct jffs2_node_frag *this)
 102 {
 103         if (this->node) {
 104                 this->node->frags--;
 105                 if (!this->node->frags) {
 106                         /* The node has no valid frags left. It's totally obsoleted */
 107                         dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) obsolete\n",
 108                                 ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size);
 109                         jffs2_mark_node_obsolete(c, this->node->raw);
 110                         jffs2_free_full_dnode(this->node);
 111                 } else {
 112                         dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) REF_NORMAL. frags is %d\n",
 113                                 ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size, this->node->frags);
 114                         mark_ref_normal(this->node->raw);
 115                 }
 116
 117         }
 118         jffs2_free_node_frag(this);
 119 }
 120
 121 static void jffs2_fragtree_insert(struct jffs2_node_frag *newfrag, struct jffs2_node_frag *base)
 122 {
 123         struct rb_node *parent = &base->rb;
 124         struct rb_node **link = &parent;
 125
 126         dbg_fragtree2("insert frag (0x%04x-0x%04x)\n", newfrag->ofs, newfrag->ofs + newfrag->size);
 127
 128         while (*link) {
 129                 parent = *link;
 130                 base = rb_entry(parent, struct jffs2_node_frag, rb);
 131
 132                 if (newfrag->ofs > base->ofs)
 133                         link = &base->rb.rb_right;
 134                 else if (newfrag->ofs < base->ofs)
 135                         link = &base->rb.rb_left;
 136                 else {
 137                         JFFS2_ERROR("duplicate frag at %08x (%p,%p)\n", newfrag->ofs, newfrag, base);
 138                         BUG();
 139                 }
 140         }
 141
 142         rb_link_node(&newfrag->rb, &base->rb, link);
 143 }
 144
 145 /*
 146  * Allocate and initializes a new fragment.
 147  */
 148 static struct jffs2_node_frag * new_fragment(struct jffs2_full_dnode *fn, uint32_t ofs, uint32_t size)
 149 {
 150         struct jffs2_node_frag *newfrag;
 151
 152         newfrag = jffs2_alloc_node_frag();
 153         if (likely(newfrag)) {
 154                 newfrag->ofs = ofs;
 155                 newfrag->size = size;
 156                 newfrag->node = fn;
 157         } else {
 158                 JFFS2_ERROR("cannot allocate a jffs2_node_frag object\n");
 159         }
 160
 161         return newfrag;
 162 }
 163
 164 /*
 165  * Called when there is no overlapping fragment exist. Inserts a hole before the new
 166  * fragment and inserts the new fragment to the fragtree.
 167  */
 168 static int no_overlapping_node(struct jffs2_sb_info *c, struct rb_root *root,
 169                                struct jffs2_node_frag *newfrag,
 170                                struct jffs2_node_frag *this, uint32_t lastend)
 171 {
 172         if (lastend < newfrag->node->ofs) {
 173                 /* put a hole in before the new fragment */
 174                 struct jffs2_node_frag *holefrag;
 175
 176                 holefrag= new_fragment(NULL, lastend, newfrag->node->ofs - lastend);
 177                 if (unlikely(!holefrag)) {
 178                         jffs2_free_node_frag(newfrag);
 179                         return -ENOMEM;
 180                 }
 181
 182                 if (this) {
 183                         /* By definition, the 'this' node has no right-hand child,
 184                            because there are no frags with offset greater than it.
 185                            So that's where we want to put the hole */
 186                         dbg_fragtree2("add hole frag %#04x-%#04x on the right of the new frag.\n",
 187                                 holefrag->ofs, holefrag->ofs + holefrag->size);
 188                         rb_link_node(&holefrag->rb, &this->rb, &this->rb.rb_right);
 189                 } else {
 190                         dbg_fragtree2("Add hole frag %#04x-%#04x to the root of the tree.\n",
 191                                 holefrag->ofs, holefrag->ofs + holefrag->size);
 192                         rb_link_node(&holefrag->rb, NULL, &root->rb_node);
 193                 }
 194                 rb_insert_color(&holefrag->rb, root);
 195                 this = holefrag;
 196         }
 197
 198         if (this) {
 199                 /* By definition, the 'this' node has no right-hand child,
 200                    because there are no frags with offset greater than it.
 201                    So that's where we want to put new fragment */
 202                 dbg_fragtree2("add the new node at the right\n");
 203                 rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right);
 204         } else {
 205                 dbg_fragtree2("insert the new node at the root of the tree\n");
 206                 rb_link_node(&newfrag->rb, NULL, &root->rb_node);
 207         }
 208         rb_insert_color(&newfrag->rb, root);
 209
 210         return 0;
 211 }
 212
 213 /* Doesn't set inode->i_size */
 214 static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *root, struct jffs2_node_frag *newfrag)
 215 {
 216         struct jffs2_node_frag *this;
 217         uint32_t lastend;
 218
 219         /* Skip all the nodes which are completed before this one starts */
 220         this = jffs2_lookup_node_frag(root, newfrag->node->ofs);
 221
 222         if (this) {
 223                 dbg_fragtree2("lookup gave frag 0x%04x-0x%04x; phys 0x%08x (*%p)\n",
 224                           this->ofs, this->ofs+this->size, this->node?(ref_offset(this->node->raw)):0xffffffff, this);
 225                 lastend = this->ofs + this->size;
 226         } else {
 227                 dbg_fragtree2("lookup gave no frag\n");
 228                 lastend = 0;
 229         }
 230
 231         /* See if we ran off the end of the fragtree */
 232         if (lastend <= newfrag->ofs) {
 233                 /* We did */
 234
 235                 /* Check if 'this' node was on the same page as the new node.
 236                    If so, both 'this' and the new node get marked REF_NORMAL so
 237                    the GC can take a look.
 238                 */
 239                 if (lastend && (lastend-1) >> PAGE_CACHE_SHIFT == newfrag->ofs >> PAGE_CACHE_SHIFT) {
 240                         if (this->node)
 241                                 mark_ref_normal(this->node->raw);
 242                         mark_ref_normal(newfrag->node->raw);
 243                 }
 244
 245                 return no_overlapping_node(c, root, newfrag, this, lastend);
 246         }
 247
 248         if (this->node)
 249                 dbg_fragtree2("dealing with frag %u-%u, phys %#08x(%d).\n",
 250                 this->ofs, this->ofs + this->size,
 251                 ref_offset(this->node->raw), ref_flags(this->node->raw));
 252         else
 253                 dbg_fragtree2("dealing with hole frag %u-%u.\n",
 254                 this->ofs, this->ofs + this->size);
 255
 256         /* OK. 'this' is pointing at the first frag that newfrag->ofs at least partially obsoletes,
 257          * - i.e. newfrag->ofs < this->ofs+this->size && newfrag->ofs >= this->ofs
 258          */
 259         if (newfrag->ofs > this->ofs) {
 260                 /* This node isn't completely obsoleted. The start of it remains valid */
 261
 262                 /* Mark the new node and the partially covered node REF_NORMAL -- let
 263                    the GC take a look at them */
 264                 mark_ref_normal(newfrag->node->raw);
 265                 if (this->node)
 266                         mark_ref_normal(this->node->raw);
 267
 268                 if (this->ofs + this->size > newfrag->ofs + newfrag->size) {
 269                         /* The new node splits 'this' frag into two */
 270                         struct jffs2_node_frag *newfrag2;
 271
 272                         if (this->node)
 273                                 dbg_fragtree2("split old frag 0x%04x-0x%04x, phys 0x%08x\n",
 274                                         this->ofs, this->ofs+this->size, ref_offset(this->node->raw));
 275                         else
 276                                 dbg_fragtree2("split old hole frag 0x%04x-0x%04x\n",
 277                                         this->ofs, this->ofs+this->size);
 278
 279                         /* New second frag pointing to this's node */
 280                         newfrag2 = new_fragment(this->node, newfrag->ofs + newfrag->size,
 281                                                 this->ofs + this->size - newfrag->ofs - newfrag->size);
 282                         if (unlikely(!newfrag2))
 283                                 return -ENOMEM;
 284                         if (this->node)
 285                                 this->node->frags++;
 286
 287                         /* Adjust size of original 'this' */
 288                         this->size = newfrag->ofs - this->ofs;
 289
 290                         /* Now, we know there's no node with offset
 291                            greater than this->ofs but smaller than
 292                            newfrag2->ofs or newfrag->ofs, for obvious
 293                            reasons. So we can do a tree insert from
 294                            'this' to insert newfrag, and a tree insert
 295                            from newfrag to insert newfrag2. */
 296                         jffs2_fragtree_insert(newfrag, this);
 297                         rb_insert_color(&newfrag->rb, root);
 298
 299                         jffs2_fragtree_insert(newfrag2, newfrag);
 300                         rb_insert_color(&newfrag2->rb, root);
 301
 302                         return 0;
 303                 }
 304                 /* New node just reduces 'this' frag in size, doesn't split it */
 305                 this->size = newfrag->ofs - this->ofs;
 306
 307                 /* Again, we know it lives down here in the tree */
 308                 jffs2_fragtree_insert(newfrag, this);
 309                 rb_insert_color(&newfrag->rb, root);
 310         } else {
 311                 /* New frag starts at the same point as 'this' used to. Replace
 312                    it in the tree without doing a delete and insertion */
 313                 dbg_fragtree2("inserting newfrag (*%p),%d-%d in before 'this' (*%p),%d-%d\n",
 314                           newfrag, newfrag->ofs, newfrag->ofs+newfrag->size, this, this->ofs, this->ofs+this->size);
 315
 316                 rb_replace_node(&this->rb, &newfrag->rb, root);
 317
 318                 if (newfrag->ofs + newfrag->size >= this->ofs+this->size) {
 319                         dbg_fragtree2("obsoleting node frag %p (%x-%x)\n", this, this->ofs, this->ofs+this->size);
 320                         jffs2_obsolete_node_frag(c, this);
 321                 } else {
 322                         this->ofs += newfrag->size;
 323                         this->size -= newfrag->size;
 324
 325                         jffs2_fragtree_insert(this, newfrag);
 326                         rb_insert_color(&this->rb, root);
 327                         return 0;
 328                 }
 329         }
 330         /* OK, now we have newfrag added in the correct place in the tree, but
 331            frag_next(newfrag) may be a fragment which is overlapped by it
 332         */
 333         while ((this = frag_next(newfrag)) && newfrag->ofs + newfrag->size >= this->ofs + this->size) {
 334                 /* 'this' frag is obsoleted completely. */
 335                 dbg_fragtree2("obsoleting node frag %p (%x-%x) and removing from tree\n",
 336                         this, this->ofs, this->ofs+this->size);
 337                 rb_erase(&this->rb, root);
 338                 jffs2_obsolete_node_frag(c, this);
 339         }
 340         /* Now we're pointing at the first frag which isn't totally obsoleted by
 341            the new frag */
 342
 343         if (!this || newfrag->ofs + newfrag->size == this->ofs)
 344                 return 0;
 345
 346         /* Still some overlap but we don't need to move it in the tree */
 347         this->size = (this->ofs + this->size) - (newfrag->ofs + newfrag->size);
 348         this->ofs = newfrag->ofs + newfrag->size;
 349
 350         /* And mark them REF_NORMAL so the GC takes a look at them */
 351         if (this->node)
 352                 mark_ref_normal(this->node->raw);
 353         mark_ref_normal(newfrag->node->raw);
 354
 355         return 0;
 356 }
 357
 358 /*
 359  * Given an inode, probably with existing tree of fragments, add the new node
 360  * to the fragment tree.
 361  */
 362 int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn)
 363 {
 364         int ret;
 365         struct jffs2_node_frag *newfrag;
 366
 367         if (unlikely(!fn->size))
 368                 return 0;
 369
 370         newfrag = new_fragment(fn, fn->ofs, fn->size);
 371         if (unlikely(!newfrag))
 372                 return -ENOMEM;
 373         newfrag->node->frags = 1;
 374
 375         dbg_fragtree("adding node %#04x-%#04x @0x%08x on flash, newfrag *%p\n",
 376                   fn->ofs, fn->ofs+fn->size, ref_offset(fn->raw), newfrag);
 377
 378         ret = jffs2_add_frag_to_fragtree(c, &f->fragtree, newfrag);
 379         if (unlikely(ret))
 380                 return ret;
 381
 382         /* If we now share a page with other nodes, mark either previous
 383            or next node REF_NORMAL, as appropriate.  */
 384         if (newfrag->ofs & (PAGE_CACHE_SIZE-1)) {
 385                 struct jffs2_node_frag *prev = frag_prev(newfrag);
 386
 387                 mark_ref_normal(fn->raw);
 388                 /* If we don't start at zero there's _always_ a previous */
 389                 if (prev->node)
 390                         mark_ref_normal(prev->node->raw);
 391         }
 392
 393         if ((newfrag->ofs+newfrag->size) & (PAGE_CACHE_SIZE-1)) {
 394                 struct jffs2_node_frag *next = frag_next(newfrag);
 395
 396                 if (next) {
 397                         mark_ref_normal(fn->raw);
 398                         if (next->node)
 399                                 mark_ref_normal(next->node->raw);
 400                 }
 401         }
 402         jffs2_dbg_fragtree_paranoia_check_nolock(f);
 403
 404         return 0;
 405 }
 406
 407 void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state)
 408 {
 409         spin_lock(&c->inocache_lock);
 410         ic->state = state;
 411         wake_up(&c->inocache_wq);
 412         spin_unlock(&c->inocache_lock);
 413 }
 414
 415 /* During mount, this needs no locking. During normal operation, its
 416    callers want to do other stuff while still holding the inocache_lock.
 417    Rather than introducing special case get_ino_cache functions or
 418    callbacks, we just let the caller do the locking itself. */
 419
 420 struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
 421 {
 422         struct jffs2_inode_cache *ret;
 423
 424         ret = c->inocache_list[ino % INOCACHE_HASHSIZE];
 425         while (ret && ret->ino < ino) {
 426                 ret = ret->next;
 427         }
 428
 429         if (ret && ret->ino != ino)
 430                 ret = NULL;
 431
 432         return ret;
 433 }
 434
 435 void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new)
 436 {
 437         struct jffs2_inode_cache **prev;
 438
 439         spin_lock(&c->inocache_lock);
 440         if (!new->ino)
 441                 new->ino = ++c->highest_ino;
 442
 443         dbg_inocache("add %p (ino #%u)\n", new, new->ino);
 444
 445         prev = &c->inocache_list[new->ino % INOCACHE_HASHSIZE];
 446
 447         while ((*prev) && (*prev)->ino < new->ino) {
 448                 prev = &(*prev)->next;
 449         }
 450         new->next = *prev;
 451         *prev = new;
 452
 453         spin_unlock(&c->inocache_lock);
 454 }
 455
 456 void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old)
 457 {
 458         struct jffs2_inode_cache **prev;
 459
 460 #ifdef CONFIG_JFFS2_FS_XATTR
 461         BUG_ON(old->xref);
 462 #endif
 463         dbg_inocache("del %p (ino #%u)\n", old, old->ino);
 464         spin_lock(&c->inocache_lock);
 465
 466         prev = &c->inocache_list[old->ino % INOCACHE_HASHSIZE];
 467
 468         while ((*prev) && (*prev)->ino < old->ino) {
 469                 prev = &(*prev)->next;
 470         }
 471         if ((*prev) == old) {
 472                 *prev = old->next;
 473         }
 474
 475         /* Free it now unless it's in READING or CLEARING state, which
 476            are the transitions upon read_inode() and clear_inode(). The
 477            rest of the time we know nobody else is looking at it, and
 478            if it's held by read_inode() or clear_inode() they'll free it
 479            for themselves. */
 480         if (old->state != INO_STATE_READING && old->state != INO_STATE_CLEARING)
 481                 jffs2_free_inode_cache(old);
 482
 483         spin_unlock(&c->inocache_lock);
 484 }
 485
 486 void jffs2_free_ino_caches(struct jffs2_sb_info *c)
 487 {
 488         int i;
 489         struct jffs2_inode_cache *this, *next;
 490
 491         for (i=0; i<INOCACHE_HASHSIZE; i++) {
 492                 this = c->inocache_list[i];
 493                 while (this) {
 494                         next = this->next;
 495                         jffs2_xattr_free_inode(c, this);
 496                         jffs2_free_inode_cache(this);
 497                         this = next;
 498                 }
 499                 c->inocache_list[i] = NULL;
 500         }
 501 }
 502
 503 void jffs2_free_raw_node_refs(struct jffs2_sb_info *c)
 504 {
 505         int i;
 506         struct jffs2_raw_node_ref *this, *next;
 507
 508         for (i=0; i<c->nr_blocks; i++) {
 509                 this = c->blocks[i].first_node;
 510                 while (this) {
 511                         if (this[REFS_PER_BLOCK].flash_offset == REF_LINK_NODE)
 512                                 next = this[REFS_PER_BLOCK].next_in_ino;
 513                         else
 514                                 next = NULL;
 515
 516                         jffs2_free_refblock(this);
 517                         this = next;
 518                 }
 519                 c->blocks[i].first_node = c->blocks[i].last_node = NULL;
 520         }
 521 }
 522
 523 struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset)
 524 {
 525         /* The common case in lookup is that there will be a node
 526            which precisely matches. So we go looking for that first */
 527         struct rb_node *next;
 528         struct jffs2_node_frag *prev = NULL;
 529         struct jffs2_node_frag *frag = NULL;
 530
 531         dbg_fragtree2("root %p, offset %d\n", fragtree, offset);
 532
 533         next = fragtree->rb_node;
 534
 535         while(next) {
 536                 frag = rb_entry(next, struct jffs2_node_frag, rb);
 537
 538                 if (frag->ofs + frag->size <= offset) {
 539                         /* Remember the closest smaller match on the way down */
 540                         if (!prev || frag->ofs > prev->ofs)
 541                                 prev = frag;
 542                         next = frag->rb.rb_right;
 543                 } else if (frag->ofs > offset) {
 544                         next = frag->rb.rb_left;
 545                 } else {
 546                         return frag;
 547                 }
 548         }
 549
 550         /* Exact match not found. Go back up looking at each parent,
 551            and return the closest smaller one */
 552
 553         if (prev)
 554                 dbg_fragtree2("no match. Returning frag %#04x-%#04x, closest previous\n",
 555                           prev->ofs, prev->ofs+prev->size);
 556         else
 557                 dbg_fragtree2("returning NULL, empty fragtree\n");
 558
 559         return prev;
 560 }
 561
 562 /* Pass 'c' argument to indicate that nodes should be marked obsolete as
 563    they're killed. */
 564 void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c)
 565 {
 566         struct jffs2_node_frag *frag;
 567         struct jffs2_node_frag *parent;
 568
 569         if (!root->rb_node)
 570                 return;
 571
 572         dbg_fragtree("killing\n");
 573
 574         frag = (rb_entry(root->rb_node, struct jffs2_node_frag, rb));
 575         while(frag) {
 576                 if (frag->rb.rb_left) {
 577                         frag = frag_left(frag);
 578                         continue;
 579                 }
 580                 if (frag->rb.rb_right) {
 581                         frag = frag_right(frag);
 582                         continue;
 583                 }
 584
 585                 if (frag->node && !(--frag->node->frags)) {
 586                         /* Not a hole, and it's the final remaining frag
 587                            of this node. Free the node */
 588                         if (c)
 589                                 jffs2_mark_node_obsolete(c, frag->node->raw);
 590
 591                         jffs2_free_full_dnode(frag->node);
 592                 }
 593                 parent = frag_parent(frag);
 594                 if (parent) {
 595                         if (frag_left(parent) == frag)
 596                                 parent->rb.rb_left = NULL;
 597                         else
 598                                 parent->rb.rb_right = NULL;
 599                 }
 600
 601                 jffs2_free_node_frag(frag);
 602                 frag = parent;
 603
 604                 cond_resched();
 605         }
 606 }
 607
 608 struct jffs2_raw_node_ref *jffs2_link_node_ref(struct jffs2_sb_info *c,
 609                                                struct jffs2_eraseblock *jeb,
 610                                                uint32_t ofs, uint32_t len,
 611                                                struct jffs2_inode_cache *ic)
 612 {
 613         struct jffs2_raw_node_ref *ref;
 614
 615         BUG_ON(!jeb->allocated_refs);
 616         jeb->allocated_refs--;
 617
 618         ref = jeb->last_node;
 619
 620         dbg_noderef("Last node at %p is (%08x,%p)\n", ref, ref->flash_offset,
 621                     ref->next_in_ino);
 622
 623         while (ref->flash_offset != REF_EMPTY_NODE) {
 624                 if (ref->flash_offset == REF_LINK_NODE)
 625                         ref = ref->next_in_ino;
 626                 else
 627                         ref++;
 628         }
 629
 630         dbg_noderef("New ref is %p (%08x becomes %08x,%p) len 0x%x\n", ref,
 631                     ref->flash_offset, ofs, ref->next_in_ino, len);
 632
 633         ref->flash_offset = ofs;
 634
 635         if (!jeb->first_node) {
 636                 jeb->first_node = ref;
 637                 BUG_ON(ref_offset(ref) != jeb->offset);
 638         } else if (unlikely(ref_offset(ref) != jeb->offset + c->sector_size - jeb->free_size)) {
 639                 uint32_t last_len = ref_totlen(c, jeb, jeb->last_node);
 640
 641                 JFFS2_ERROR("Adding new ref %p at (0x%08x-0x%08x) not immediately after previous (0x%08x-0x%08x)\n",
 642                             ref, ref_offset(ref), ref_offset(ref)+len,
 643                             ref_offset(jeb->last_node),
 644                             ref_offset(jeb->last_node)+last_len);
 645                 BUG();
 646         }
 647         jeb->last_node = ref;
 648
 649         if (ic) {
 650                 ref->next_in_ino = ic->nodes;
 651                 ic->nodes = ref;
 652         } else {
 653                 ref->next_in_ino = NULL;
 654         }
 655
 656         switch(ref_flags(ref)) {
 657         case REF_UNCHECKED:
 658                 c->unchecked_size += len;
 659                 jeb->unchecked_size += len;
 660                 break;
 661
 662         case REF_NORMAL:
 663         case REF_PRISTINE:
 664                 c->used_size += len;
 665                 jeb->used_size += len;
 666                 break;
 667
 668         case REF_OBSOLETE:
 669                 c->dirty_size += len;
 670                 jeb->dirty_size += len;
 671                 break;
 672         }
 673         c->free_size -= len;
 674         jeb->free_size -= len;
 675
 676 #ifdef TEST_TOTLEN
 677         /* Set (and test) __totlen field... for now */
 678         ref->__totlen = len;
 679         ref_totlen(c, jeb, ref);
 680 #endif
 681         return ref;
 682 }
 683
 684 /* No locking, no reservation of 'ref'. Do not use on a live file system */
 685 int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 686                            uint32_t size)
 687 {
 688         if (!size)
 689                 return 0;
 690         if (unlikely(size > jeb->free_size)) {
 691                 printk(KERN_CRIT "Dirty space 0x%x larger then free_size 0x%x (wasted 0x%x)\n",
 692                        size, jeb->free_size, jeb->wasted_size);
 693                 BUG();
 694         }
 695         /* REF_EMPTY_NODE is !obsolete, so that works OK */
 696         if (jeb->last_node && ref_obsolete(jeb->last_node)) {
 697 #ifdef TEST_TOTLEN
 698                 jeb->last_node->__totlen += size;
 699 #endif
 700                 c->dirty_size += size;
 701                 c->free_size -= size;
 702                 jeb->dirty_size += size;
 703                 jeb->free_size -= size;
 704         } else {
 705                 uint32_t ofs = jeb->offset + c->sector_size - jeb->free_size;
 706                 ofs |= REF_OBSOLETE;
 707
 708                 jffs2_link_node_ref(c, jeb, ofs, size, NULL);
 709         }
 710
 711         return 0;
 712 }
 713
 714 /* Calculate totlen from surrounding nodes or eraseblock */
 715 static inline uint32_t __ref_totlen(struct jffs2_sb_info *c,
 716                                     struct jffs2_eraseblock *jeb,
 717                                     struct jffs2_raw_node_ref *ref)
 718 {
 719         uint32_t ref_end;
 720         struct jffs2_raw_node_ref *next_ref = ref_next(ref);
 721
 722         if (next_ref)
 723                 ref_end = ref_offset(next_ref);
 724         else {
 725                 if (!jeb)
 726                         jeb = &c->blocks[ref->flash_offset / c->sector_size];
 727
 728                 /* Last node in block. Use free_space */
 729                 if (unlikely(ref != jeb->last_node)) {
 730                         printk(KERN_CRIT "ref %p @0x%08x is not jeb->last_node (%p @0x%08x)\n",
 731                                ref, ref_offset(ref), jeb->last_node, jeb->last_node?ref_offset(jeb->last_node):0);
 732                         BUG();
 733                 }
 734                 ref_end = jeb->offset + c->sector_size - jeb->free_size;
 735         }
 736         return ref_end - ref_offset(ref);
 737 }
 738
 739 uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 740                             struct jffs2_raw_node_ref *ref)
 741 {
 742         uint32_t ret;
 743
 744         ret = __ref_totlen(c, jeb, ref);
 745
 746 #ifdef TEST_TOTLEN
 747         if (unlikely(ret != ref->__totlen)) {
 748                 if (!jeb)
 749                         jeb = &c->blocks[ref->flash_offset / c->sector_size];
 750
 751                 printk(KERN_CRIT "Totlen for ref at %p (0x%08x-0x%08x) miscalculated as 0x%x instead of %x\n",
 752                        ref, ref_offset(ref), ref_offset(ref)+ref->__totlen,
 753                        ret, ref->__totlen);
 754                 if (ref_next(ref)) {
 755                         printk(KERN_CRIT "next %p (0x%08x-0x%08x)\n", ref_next(ref), ref_offset(ref_next(ref)),
 756                                ref_offset(ref_next(ref))+ref->__totlen);
 757                 } else
 758                         printk(KERN_CRIT "No next ref. jeb->last_node is %p\n", jeb->last_node);
 759
 760                 printk(KERN_CRIT "jeb->wasted_size %x, dirty_size %x, used_size %x, free_size %x\n", jeb->wasted_size, jeb->dirty_size, jeb->used_size, jeb->free_size);
 761
 762 #if defined(JFFS2_DBG_DUMPS) || defined(JFFS2_DBG_PARANOIA_CHECKS)
 763                 __jffs2_dbg_dump_node_refs_nolock(c, jeb);
 764 #endif
 765
 766                 WARN_ON(1);
 767
 768                 ret = ref->__totlen;
 769         }
 770 #endif /* TEST_TOTLEN */
 771         return ret;
 772 }