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 Marking new dirent node is obsolete, old is \"%s\", ino #%u\n",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