linux/fs/jffs2/nodelist.c
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   1/*
   2 * JFFS2 -- Journalling Flash File System, Version 2.
   3 *
   4 * Copyright © 2001-2007 Red Hat, Inc.
   5 *
   6 * Created by David Woodhouse <dwmw2@infradead.org>
   7 *
   8 * For licensing information, see the file 'LICENCE' in this directory.
   9 *
  10 */
  11
  12#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
  21static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
  22                                     struct jffs2_node_frag *this);
  23
  24void 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
  57uint32_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
  99static 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
 120static 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 */
 147static 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 */
 167static 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 */
 213static 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 */
 361int 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
 406void 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
 419struct 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
 434void 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
 455void 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
 485void 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
 502void 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
 522struct 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. */
 563void 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
 607struct 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 */
 684int 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 */
 714static 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
 738uint32_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}
 772