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