fs/jffs2/nodelist.c

   1 /*
   2  * JFFS2 -- Journalling Flash File System, Version 2.
   3  *
   4  * Copyright (C) 2001-2003 Red Hat, Inc.
   5  *
   6  * Created by David Woodhouse <dwmw2@infradead.org>
   7  *
   8  * For licensing information, see the file 'LICENCE' in this directory.
   9  *
  10  * $Id: nodelist.c,v 1.115 2005/11/07 11:14:40 gleixner Exp $
  11  *
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/sched.h>
  16 #include <linux/fs.h>
  17 #include <linux/mtd/mtd.h>
  18 #include <linux/rbtree.h>
  19 #include <linux/crc32.h>
  20 #include <linux/slab.h>
  21 #include <linux/pagemap.h>
  22 #include "nodelist.h"
  23
  24 static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
  25                                      struct jffs2_node_frag *this);
  26
  27 void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list)
  28 {
  29         struct jffs2_full_dirent **prev = list;
  30
  31         dbg_dentlist("add dirent \"%s\", ino #%u\n", new->name, new->ino);
  32
  33         while ((*prev) && (*prev)->nhash <= new->nhash) {
  34                 if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name)) {
  35                         /* Duplicate. Free one */
  36                         if (new->version < (*prev)->version) {
  37                                 dbg_dentlist("Eep! Marking new dirent node is obsolete, old is \"%s\", ino #%u\n",
  38                                         (*prev)->name, (*prev)->ino);
  39                                 jffs2_mark_node_obsolete(c, new->raw);
  40                                 jffs2_free_full_dirent(new);
  41                         } else {
  42                                 dbg_dentlist("marking old dirent \"%s\", ino #%u bsolete\n",
  43                                         (*prev)->name, (*prev)->ino);
  44                                 new->next = (*prev)->next;
  45                                 jffs2_mark_node_obsolete(c, ((*prev)->raw));
  46                                 jffs2_free_full_dirent(*prev);
  47                                 *prev = new;
  48                         }
  49                         return;
  50                 }
  51                 prev = &((*prev)->next);
  52         }
  53         new->next = *prev;
  54         *prev = new;
  55 }
  56
  57 void jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint32_t size)
  58 {
  59         struct jffs2_node_frag *frag = jffs2_lookup_node_frag(list, size);
  60
  61         dbg_fragtree("truncating fragtree to 0x%08x bytes\n", size);
  62
  63         /* We know frag->ofs <= size. That's what lookup does for us */
  64         if (frag && frag->ofs != size) {
  65                 if (frag->ofs+frag->size > size) {
  66                         frag->size = size - frag->ofs;
  67                 }
  68                 frag = frag_next(frag);
  69         }
  70         while (frag && frag->ofs >= size) {
  71                 struct jffs2_node_frag *next = frag_next(frag);
  72
  73                 frag_erase(frag, list);
  74                 jffs2_obsolete_node_frag(c, frag);
  75                 frag = next;
  76         }
  77
  78         if (size == 0)
  79                 return;
  80
  81         /*
  82          * If the last fragment starts at the RAM page boundary, it is
  83          * REF_PRISTINE irrespective of its size.
  84          */
  85         frag = frag_last(list);
  86         if (frag->node && (frag->ofs & (PAGE_CACHE_SIZE - 1)) == 0) {
  87                 dbg_fragtree2("marking the last fragment 0x%08x-0x%08x REF_PRISTINE.\n",
  88                         frag->ofs, frag->ofs + frag->size);
  89                 frag->node->raw->flash_offset = ref_offset(frag->node->raw) | REF_PRISTINE;
  90         }
  91 }
  92
  93 static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
  94                                      struct jffs2_node_frag *this)
  95 {
  96         if (this->node) {
  97                 this->node->frags--;
  98                 if (!this->node->frags) {
  99                         /* The node has no valid frags left. It's totally obsoleted */
 100                         dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) obsolete\n",
 101                                 ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size);
 102                         jffs2_mark_node_obsolete(c, this->node->raw);
 103                         jffs2_free_full_dnode(this->node);
 104                 } else {
 105                         dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) REF_NORMAL. frags is %d\n",
 106                                 ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size, this->node->frags);
 107                         mark_ref_normal(this->node->raw);
 108                 }
 109
 110         }
 111         jffs2_free_node_frag(this);
 112 }
 113
 114 static void jffs2_fragtree_insert(struct jffs2_node_frag *newfrag, struct jffs2_node_frag *base)
 115 {
 116         struct rb_node *parent = &base->rb;
 117         struct rb_node **link = &parent;
 118
 119         dbg_fragtree2("insert frag (0x%04x-0x%04x)\n", newfrag->ofs, newfrag->ofs + newfrag->size);
 120
 121         while (*link) {
 122                 parent = *link;
 123                 base = rb_entry(parent, struct jffs2_node_frag, rb);
 124
 125                 if (newfrag->ofs > base->ofs)
 126                         link = &base->rb.rb_right;
 127                 else if (newfrag->ofs < base->ofs)
 128                         link = &base->rb.rb_left;
 129                 else {
 130                         JFFS2_ERROR("duplicate frag at %08x (%p,%p)\n", newfrag->ofs, newfrag, base);
 131                         BUG();
 132                 }
 133         }
 134
 135         rb_link_node(&newfrag->rb, &base->rb, link);
 136 }
 137
 138 /*
 139  * Allocate and initializes a new fragment.
 140  */
 141 static struct jffs2_node_frag * new_fragment(struct jffs2_full_dnode *fn, uint32_t ofs, uint32_t size)
 142 {
 143         struct jffs2_node_frag *newfrag;
 144
 145         newfrag = jffs2_alloc_node_frag();
 146         if (likely(newfrag)) {
 147                 newfrag->ofs = ofs;
 148                 newfrag->size = size;
 149                 newfrag->node = fn;
 150         } else {
 151                 JFFS2_ERROR("cannot allocate a jffs2_node_frag object\n");
 152         }
 153
 154         return newfrag;
 155 }
 156
 157 /*
 158  * Called when there is no overlapping fragment exist. Inserts a hole before the new
 159  * fragment and inserts the new fragment to the fragtree.
 160  */
 161 static int no_overlapping_node(struct jffs2_sb_info *c, struct rb_root *root,
 162                                struct jffs2_node_frag *newfrag,
 163                                struct jffs2_node_frag *this, uint32_t lastend)
 164 {
 165         if (lastend < newfrag->node->ofs) {
 166                 /* put a hole in before the new fragment */
 167                 struct jffs2_node_frag *holefrag;
 168
 169                 holefrag= new_fragment(NULL, lastend, newfrag->node->ofs - lastend);
 170                 if (unlikely(!holefrag)) {
 171                         jffs2_free_node_frag(newfrag);
 172                         return -ENOMEM;
 173                 }
 174
 175                 if (this) {
 176                         /* By definition, the 'this' node has no right-hand child,
 177                            because there are no frags with offset greater than it.
 178                            So that's where we want to put the hole */
 179                         dbg_fragtree2("add hole frag %#04x-%#04x on the right of the new frag.\n",
 180                                 holefrag->ofs, holefrag->ofs + holefrag->size);
 181                         rb_link_node(&holefrag->rb, &this->rb, &this->rb.rb_right);
 182                 } else {
 183                         dbg_fragtree2("Add hole frag %#04x-%#04x to the root of the tree.\n",
 184                                 holefrag->ofs, holefrag->ofs + holefrag->size);
 185                         rb_link_node(&holefrag->rb, NULL, &root->rb_node);
 186                 }
 187                 rb_insert_color(&holefrag->rb, root);
 188                 this = holefrag;
 189         }
 190
 191         if (this) {
 192                 /* By definition, the 'this' node has no right-hand child,
 193                    because there are no frags with offset greater than it.
 194                    So that's where we want to put new fragment */
 195                 dbg_fragtree2("add the new node at the right\n");
 196                 rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right);
 197         } else {
 198                 dbg_fragtree2("insert the new node at the root of the tree\n");
 199                 rb_link_node(&newfrag->rb, NULL, &root->rb_node);
 200         }
 201         rb_insert_color(&newfrag->rb, root);
 202
 203         return 0;
 204 }
 205
 206 /* Doesn't set inode->i_size */
 207 static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *root, struct jffs2_node_frag *newfrag)
 208 {
 209         struct jffs2_node_frag *this;
 210         uint32_t lastend;
 211
 212         /* Skip all the nodes which are completed before this one starts */
 213         this = jffs2_lookup_node_frag(root, newfrag->node->ofs);
 214
 215         if (this) {
 216                 dbg_fragtree2("lookup gave frag 0x%04x-0x%04x; phys 0x%08x (*%p)\n",
 217                           this->ofs, this->ofs+this->size, this->node?(ref_offset(this->node->raw)):0xffffffff, this);
 218                 lastend = this->ofs + this->size;
 219         } else {
 220                 dbg_fragtree2("lookup gave no frag\n");
 221                 lastend = 0;
 222         }
 223
 224         /* See if we ran off the end of the fragtree */
 225         if (lastend <= newfrag->ofs) {
 226                 /* We did */
 227
 228                 /* Check if 'this' node was on the same page as the new node.
 229                    If so, both 'this' and the new node get marked REF_NORMAL so
 230                    the GC can take a look.
 231                 */
 232                 if (lastend && (lastend-1) >> PAGE_CACHE_SHIFT == newfrag->ofs >> PAGE_CACHE_SHIFT) {
 233                         if (this->node)
 234                                 mark_ref_normal(this->node->raw);
 235                         mark_ref_normal(newfrag->node->raw);
 236                 }
 237
 238                 return no_overlapping_node(c, root, newfrag, this, lastend);
 239         }
 240
 241         if (this->node)
 242                 dbg_fragtree2("dealing with frag %u-%u, phys %#08x(%d).\n",
 243                 this->ofs, this->ofs + this->size,
 244                 ref_offset(this->node->raw), ref_flags(this->node->raw));
 245         else
 246                 dbg_fragtree2("dealing with hole frag %u-%u.\n",
 247                 this->ofs, this->ofs + this->size);
 248
 249         /* OK. 'this' is pointing at the first frag that newfrag->ofs at least partially obsoletes,
 250          * - i.e. newfrag->ofs < this->ofs+this->size && newfrag->ofs >= this->ofs
 251          */
 252         if (newfrag->ofs > this->ofs) {
 253                 /* This node isn't completely obsoleted. The start of it remains valid */
 254
 255                 /* Mark the new node and the partially covered node REF_NORMAL -- let
 256                    the GC take a look at them */
 257                 mark_ref_normal(newfrag->node->raw);
 258                 if (this->node)
 259                         mark_ref_normal(this->node->raw);
 260
 261                 if (this->ofs + this->size > newfrag->ofs + newfrag->size) {
 262                         /* The new node splits 'this' frag into two */
 263                         struct jffs2_node_frag *newfrag2;
 264
 265                         if (this->node)
 266                                 dbg_fragtree2("split old frag 0x%04x-0x%04x, phys 0x%08x\n",
 267                                         this->ofs, this->ofs+this->size, ref_offset(this->node->raw));
 268                         else
 269                                 dbg_fragtree2("split old hole frag 0x%04x-0x%04x\n",
 270                                         this->ofs, this->ofs+this->size);
 271
 272                         /* New second frag pointing to this's node */
 273                         newfrag2 = new_fragment(this->node, newfrag->ofs + newfrag->size,
 274                                                 this->ofs + this->size - newfrag->ofs - newfrag->size);
 275                         if (unlikely(!newfrag2))
 276                                 return -ENOMEM;
 277                         if (this->node)
 278                                 this->node->frags++;
 279
 280                         /* Adjust size of original 'this' */
 281                         this->size = newfrag->ofs - this->ofs;
 282
 283                         /* Now, we know there's no node with offset
 284                            greater than this->ofs but smaller than
 285                            newfrag2->ofs or newfrag->ofs, for obvious
 286                            reasons. So we can do a tree insert from
 287                            'this' to insert newfrag, and a tree insert
 288                            from newfrag to insert newfrag2. */
 289                         jffs2_fragtree_insert(newfrag, this);
 290                         rb_insert_color(&newfrag->rb, root);
 291
 292                         jffs2_fragtree_insert(newfrag2, newfrag);
 293                         rb_insert_color(&newfrag2->rb, root);
 294
 295                         return 0;
 296                 }
 297                 /* New node just reduces 'this' frag in size, doesn't split it */
 298                 this->size = newfrag->ofs - this->ofs;
 299
 300                 /* Again, we know it lives down here in the tree */
 301                 jffs2_fragtree_insert(newfrag, this);
 302                 rb_insert_color(&newfrag->rb, root);
 303         } else {
 304                 /* New frag starts at the same point as 'this' used to. Replace
 305                    it in the tree without doing a delete and insertion */
 306                 dbg_fragtree2("inserting newfrag (*%p),%d-%d in before 'this' (*%p),%d-%d\n",
 307                           newfrag, newfrag->ofs, newfrag->ofs+newfrag->size, this, this->ofs, this->ofs+this->size);
 308
 309                 rb_replace_node(&this->rb, &newfrag->rb, root);
 310
 311                 if (newfrag->ofs + newfrag->size >= this->ofs+this->size) {
 312                         dbg_fragtree2("obsoleting node frag %p (%x-%x)\n", this, this->ofs, this->ofs+this->size);
 313                         jffs2_obsolete_node_frag(c, this);
 314                 } else {
 315                         this->ofs += newfrag->size;
 316                         this->size -= newfrag->size;
 317
 318                         jffs2_fragtree_insert(this, newfrag);
 319                         rb_insert_color(&this->rb, root);
 320                         return 0;
 321                 }
 322         }
 323         /* OK, now we have newfrag added in the correct place in the tree, but
 324            frag_next(newfrag) may be a fragment which is overlapped by it
 325         */
 326         while ((this = frag_next(newfrag)) && newfrag->ofs + newfrag->size >= this->ofs + this->size) {
 327                 /* 'this' frag is obsoleted completely. */
 328                 dbg_fragtree2("obsoleting node frag %p (%x-%x) and removing from tree\n",
 329                         this, this->ofs, this->ofs+this->size);
 330                 rb_erase(&this->rb, root);
 331                 jffs2_obsolete_node_frag(c, this);
 332         }
 333         /* Now we're pointing at the first frag which isn't totally obsoleted by
 334            the new frag */
 335
 336         if (!this || newfrag->ofs + newfrag->size == this->ofs)
 337                 return 0;
 338
 339         /* Still some overlap but we don't need to move it in the tree */
 340         this->size = (this->ofs + this->size) - (newfrag->ofs + newfrag->size);
 341         this->ofs = newfrag->ofs + newfrag->size;
 342
 343         /* And mark them REF_NORMAL so the GC takes a look at them */
 344         if (this->node)
 345                 mark_ref_normal(this->node->raw);
 346         mark_ref_normal(newfrag->node->raw);
 347
 348         return 0;
 349 }
 350
 351 /*
 352  * Given an inode, probably with existing tree of fragments, add the new node
 353  * to the fragment tree.
 354  */
 355 int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn)
 356 {
 357         int ret;
 358         struct jffs2_node_frag *newfrag;
 359
 360         if (unlikely(!fn->size))
 361                 return 0;
 362
 363         newfrag = new_fragment(fn, fn->ofs, fn->size);
 364         if (unlikely(!newfrag))
 365                 return -ENOMEM;
 366         newfrag->node->frags = 1;
 367
 368         dbg_fragtree("adding node %#04x-%#04x @0x%08x on flash, newfrag *%p\n",
 369                   fn->ofs, fn->ofs+fn->size, ref_offset(fn->raw), newfrag);
 370
 371         ret = jffs2_add_frag_to_fragtree(c, &f->fragtree, newfrag);
 372         if (unlikely(ret))
 373                 return ret;
 374
 375         /* If we now share a page with other nodes, mark either previous
 376            or next node REF_NORMAL, as appropriate.  */
 377         if (newfrag->ofs & (PAGE_CACHE_SIZE-1)) {
 378                 struct jffs2_node_frag *prev = frag_prev(newfrag);
 379
 380                 mark_ref_normal(fn->raw);
 381                 /* If we don't start at zero there's _always_ a previous */
 382                 if (prev->node)
 383                         mark_ref_normal(prev->node->raw);
 384         }
 385
 386         if ((newfrag->ofs+newfrag->size) & (PAGE_CACHE_SIZE-1)) {
 387                 struct jffs2_node_frag *next = frag_next(newfrag);
 388
 389                 if (next) {
 390                         mark_ref_normal(fn->raw);
 391                         if (next->node)
 392                                 mark_ref_normal(next->node->raw);
 393                 }
 394         }
 395         jffs2_dbg_fragtree_paranoia_check_nolock(f);
 396
 397         return 0;
 398 }
 399
 400 void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state)
 401 {
 402         spin_lock(&c->inocache_lock);
 403         ic->state = state;
 404         wake_up(&c->inocache_wq);
 405         spin_unlock(&c->inocache_lock);
 406 }
 407
 408 /* During mount, this needs no locking. During normal operation, its
 409    callers want to do other stuff while still holding the inocache_lock.
 410    Rather than introducing special case get_ino_cache functions or
 411    callbacks, we just let the caller do the locking itself. */
 412
 413 struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
 414 {
 415         struct jffs2_inode_cache *ret;
 416
 417         ret = c->inocache_list[ino % INOCACHE_HASHSIZE];
 418         while (ret && ret->ino < ino) {
 419                 ret = ret->next;
 420         }
 421
 422         if (ret && ret->ino != ino)
 423                 ret = NULL;
 424
 425         return ret;
 426 }
 427
 428 void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new)
 429 {
 430         struct jffs2_inode_cache **prev;
 431
 432         spin_lock(&c->inocache_lock);
 433         if (!new->ino)
 434                 new->ino = ++c->highest_ino;
 435
 436         dbg_inocache("add %p (ino #%u)\n", new, new->ino);
 437
 438         prev = &c->inocache_list[new->ino % INOCACHE_HASHSIZE];
 439
 440         while ((*prev) && (*prev)->ino < new->ino) {
 441                 prev = &(*prev)->next;
 442         }
 443         new->next = *prev;
 444         *prev = new;
 445
 446         spin_unlock(&c->inocache_lock);
 447 }
 448
 449 void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old)
 450 {
 451         struct jffs2_inode_cache **prev;
 452
 453 #ifdef CONFIG_JFFS2_FS_XATTR
 454         BUG_ON(old->xref);
 455 #endif
 456         dbg_inocache("del %p (ino #%u)\n", old, old->ino);
 457         spin_lock(&c->inocache_lock);
 458
 459         prev = &c->inocache_list[old->ino % INOCACHE_HASHSIZE];
 460
 461         while ((*prev) && (*prev)->ino < old->ino) {
 462                 prev = &(*prev)->next;
 463         }
 464         if ((*prev) == old) {
 465                 *prev = old->next;
 466         }
 467
 468         /* Free it now unless it's in READING or CLEARING state, which
 469            are the transitions upon read_inode() and clear_inode(). The
 470            rest of the time we know nobody else is looking at it, and
 471            if it's held by read_inode() or clear_inode() they'll free it
 472            for themselves. */
 473         if (old->state != INO_STATE_READING && old->state != INO_STATE_CLEARING)
 474                 jffs2_free_inode_cache(old);
 475
 476         spin_unlock(&c->inocache_lock);
 477 }
 478
 479 void jffs2_free_ino_caches(struct jffs2_sb_info *c)
 480 {
 481         int i;
 482         struct jffs2_inode_cache *this, *next;
 483
 484         for (i=0; i<INOCACHE_HASHSIZE; i++) {
 485                 this = c->inocache_list[i];
 486                 while (this) {
 487                         next = this->next;
 488                         jffs2_xattr_free_inode(c, this);
 489                         jffs2_free_inode_cache(this);
 490                         this = next;
 491                 }
 492                 c->inocache_list[i] = NULL;
 493         }
 494 }
 495
 496 void jffs2_free_raw_node_refs(struct jffs2_sb_info *c)
 497 {
 498         int i;
 499         struct jffs2_raw_node_ref *this, *next;
 500
 501         for (i=0; i<c->nr_blocks; i++) {
 502                 this = c->blocks[i].first_node;
 503                 while (this) {
 504                         if (this[REFS_PER_BLOCK].flash_offset == REF_LINK_NODE)
 505                                 next = this[REFS_PER_BLOCK].next_in_ino;
 506                         else
 507                                 next = NULL;
 508
 509                         jffs2_free_refblock(this);
 510                         this = next;
 511                 }
 512                 c->blocks[i].first_node = c->blocks[i].last_node = NULL;
 513         }
 514 }
 515
 516 struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset)
 517 {
 518         /* The common case in lookup is that there will be a node
 519            which precisely matches. So we go looking for that first */
 520         struct rb_node *next;
 521         struct jffs2_node_frag *prev = NULL;
 522         struct jffs2_node_frag *frag = NULL;
 523
 524         dbg_fragtree2("root %p, offset %d\n", fragtree, offset);
 525
 526         next = fragtree->rb_node;
 527
 528         while(next) {
 529                 frag = rb_entry(next, struct jffs2_node_frag, rb);
 530
 531                 if (frag->ofs + frag->size <= offset) {
 532                         /* Remember the closest smaller match on the way down */
 533                         if (!prev || frag->ofs > prev->ofs)
 534                                 prev = frag;
 535                         next = frag->rb.rb_right;
 536                 } else if (frag->ofs > offset) {
 537                         next = frag->rb.rb_left;
 538                 } else {
 539                         return frag;
 540                 }
 541         }
 542
 543         /* Exact match not found. Go back up looking at each parent,
 544            and return the closest smaller one */
 545
 546         if (prev)
 547                 dbg_fragtree2("no match. Returning frag %#04x-%#04x, closest previous\n",
 548                           prev->ofs, prev->ofs+prev->size);
 549         else
 550                 dbg_fragtree2("returning NULL, empty fragtree\n");
 551
 552         return prev;
 553 }
 554
 555 /* Pass 'c' argument to indicate that nodes should be marked obsolete as
 556    they're killed. */
 557 void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c)
 558 {
 559         struct jffs2_node_frag *frag;
 560         struct jffs2_node_frag *parent;
 561
 562         if (!root->rb_node)
 563                 return;
 564
 565         dbg_fragtree("killing\n");
 566
 567         frag = (rb_entry(root->rb_node, struct jffs2_node_frag, rb));
 568         while(frag) {
 569                 if (frag->rb.rb_left) {
 570                         frag = frag_left(frag);
 571                         continue;
 572                 }
 573                 if (frag->rb.rb_right) {
 574                         frag = frag_right(frag);
 575                         continue;
 576                 }
 577
 578                 if (frag->node && !(--frag->node->frags)) {
 579                         /* Not a hole, and it's the final remaining frag
 580                            of this node. Free the node */
 581                         if (c)
 582                                 jffs2_mark_node_obsolete(c, frag->node->raw);
 583
 584                         jffs2_free_full_dnode(frag->node);
 585                 }
 586                 parent = frag_parent(frag);
 587                 if (parent) {
 588                         if (frag_left(parent) == frag)
 589                                 parent->rb.rb_left = NULL;
 590                         else
 591                                 parent->rb.rb_right = NULL;
 592                 }
 593
 594                 jffs2_free_node_frag(frag);
 595                 frag = parent;
 596
 597                 cond_resched();
 598         }
 599 }
 600
 601 struct jffs2_raw_node_ref *jffs2_link_node_ref(struct jffs2_sb_info *c,
 602                                                struct jffs2_eraseblock *jeb,
 603                                                uint32_t ofs, uint32_t len,
 604                                                struct jffs2_inode_cache *ic)
 605 {
 606         struct jffs2_raw_node_ref *ref;
 607
 608         BUG_ON(!jeb->allocated_refs);
 609         jeb->allocated_refs--;
 610
 611         ref = jeb->last_node;
 612
 613         dbg_noderef("Last node at %p is (%08x,%p)\n", ref, ref->flash_offset,
 614                     ref->next_in_ino);
 615
 616         while (ref->flash_offset != REF_EMPTY_NODE) {
 617                 if (ref->flash_offset == REF_LINK_NODE)
 618                         ref = ref->next_in_ino;
 619                 else
 620                         ref++;
 621         }
 622
 623         dbg_noderef("New ref is %p (%08x becomes %08x,%p) len 0x%x\n", ref,
 624                     ref->flash_offset, ofs, ref->next_in_ino, len);
 625
 626         ref->flash_offset = ofs;
 627
 628         if (!jeb->first_node) {
 629                 jeb->first_node = ref;
 630                 BUG_ON(ref_offset(ref) != jeb->offset);
 631         } else if (unlikely(ref_offset(ref) != jeb->offset + c->sector_size - jeb->free_size)) {
 632                 uint32_t last_len = ref_totlen(c, jeb, jeb->last_node);
 633
 634                 JFFS2_ERROR("Adding new ref %p at (0x%08x-0x%08x) not immediately after previous (0x%08x-0x%08x)\n",
 635                             ref, ref_offset(ref), ref_offset(ref)+len,
 636                             ref_offset(jeb->last_node),
 637                             ref_offset(jeb->last_node)+last_len);
 638                 BUG();
 639         }
 640         jeb->last_node = ref;
 641
 642         if (ic) {
 643                 ref->next_in_ino = ic->nodes;
 644                 ic->nodes = ref;
 645         } else {
 646                 ref->next_in_ino = NULL;
 647         }
 648
 649         switch(ref_flags(ref)) {
 650         case REF_UNCHECKED:
 651                 c->unchecked_size += len;
 652                 jeb->unchecked_size += len;
 653                 break;
 654
 655         case REF_NORMAL:
 656         case REF_PRISTINE:
 657                 c->used_size += len;
 658                 jeb->used_size += len;
 659                 break;
 660
 661         case REF_OBSOLETE:
 662                 c->dirty_size += len;
 663                 jeb->dirty_size += len;
 664                 break;
 665         }
 666         c->free_size -= len;
 667         jeb->free_size -= len;
 668
 669 #ifdef TEST_TOTLEN
 670         /* Set (and test) __totlen field... for now */
 671         ref->__totlen = len;
 672         ref_totlen(c, jeb, ref);
 673 #endif
 674         return ref;
 675 }
 676
 677 /* No locking, no reservation of 'ref'. Do not use on a live file system */
 678 int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 679                            uint32_t size)
 680 {
 681         if (!size)
 682                 return 0;
 683         if (unlikely(size > jeb->free_size)) {
 684                 printk(KERN_CRIT "Dirty space 0x%x larger then free_size 0x%x (wasted 0x%x)\n",
 685                        size, jeb->free_size, jeb->wasted_size);
 686                 BUG();
 687         }
 688         /* REF_EMPTY_NODE is !obsolete, so that works OK */
 689         if (jeb->last_node && ref_obsolete(jeb->last_node)) {
 690 #ifdef TEST_TOTLEN
 691                 jeb->last_node->__totlen += size;
 692 #endif
 693                 c->dirty_size += size;
 694                 c->free_size -= size;
 695                 jeb->dirty_size += size;
 696                 jeb->free_size -= size;
 697         } else {
 698                 uint32_t ofs = jeb->offset + c->sector_size - jeb->free_size;
 699                 ofs |= REF_OBSOLETE;
 700
 701                 jffs2_link_node_ref(c, jeb, ofs, size, NULL);
 702         }
 703
 704         return 0;
 705 }
 706
 707 /* Calculate totlen from surrounding nodes or eraseblock */
 708 static inline uint32_t __ref_totlen(struct jffs2_sb_info *c,
 709                                     struct jffs2_eraseblock *jeb,
 710                                     struct jffs2_raw_node_ref *ref)
 711 {
 712         uint32_t ref_end;
 713         struct jffs2_raw_node_ref *next_ref = ref_next(ref);
 714
 715         if (next_ref)
 716                 ref_end = ref_offset(next_ref);
 717         else {
 718                 if (!jeb)
 719                         jeb = &c->blocks[ref->flash_offset / c->sector_size];
 720
 721                 /* Last node in block. Use free_space */
 722                 if (unlikely(ref != jeb->last_node)) {
 723                         printk(KERN_CRIT "ref %p @0x%08x is not jeb->last_node (%p @0x%08x)\n",
 724                                ref, ref_offset(ref), jeb->last_node, jeb->last_node?ref_offset(jeb->last_node):0);
 725                         BUG();
 726                 }
 727                 ref_end = jeb->offset + c->sector_size - jeb->free_size;
 728         }
 729         return ref_end - ref_offset(ref);
 730 }
 731
 732 uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 733                             struct jffs2_raw_node_ref *ref)
 734 {
 735         uint32_t ret;
 736
 737         ret = __ref_totlen(c, jeb, ref);
 738
 739 #ifdef TEST_TOTLEN
 740         if (unlikely(ret != ref->__totlen)) {
 741                 if (!jeb)
 742                         jeb = &c->blocks[ref->flash_offset / c->sector_size];
 743
 744                 printk(KERN_CRIT "Totlen for ref at %p (0x%08x-0x%08x) miscalculated as 0x%x instead of %x\n",
 745                        ref, ref_offset(ref), ref_offset(ref)+ref->__totlen,
 746                        ret, ref->__totlen);
 747                 if (ref_next(ref)) {
 748                         printk(KERN_CRIT "next %p (0x%08x-0x%08x)\n", ref_next(ref), ref_offset(ref_next(ref)),
 749                                ref_offset(ref_next(ref))+ref->__totlen);
 750                 } else
 751                         printk(KERN_CRIT "No next ref. jeb->last_node is %p\n", jeb->last_node);
 752
 753                 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);
 754
 755 #if defined(JFFS2_DBG_DUMPS) || defined(JFFS2_DBG_PARANOIA_CHECKS)
 756                 __jffs2_dbg_dump_node_refs_nolock(c, jeb);
 757 #endif
 758
 759                 WARN_ON(1);
 760
 761                 ret = ref->__totlen;
 762         }
 763 #endif /* TEST_TOTLEN */
 764         return ret;
 765 }