/*
   * JFFS2 -- Journalling Flash File System, Version 2.
   *

   * Copyright © 2001-2007 Red Hat, Inc.

   *
   * Created by David Woodhouse <dwmw2@infradead.org>
   *
   * For licensing information, see the file 'LICENCE' in this directory.
   *

   */
  
  #include <linux/kernel.h>
  #include <linux/sched.h>
  #include <linux/fs.h>
  #include <linux/mtd/mtd.h>
  #include <linux/rbtree.h>
  #include <linux/crc32.h>

  #include <linux/pagemap.h>
  #include "nodelist.h"

  static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
  				     struct jffs2_node_frag *this);

  void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list)
  {
  	struct jffs2_full_dirent **prev = list;

  	dbg_dentlist("add dirent \"%s\", ino #%u
  ", new->name, new->ino);

  
  	while ((*prev) && (*prev)->nhash <= new->nhash) {
  		if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name)) {
  			/* Duplicate. Free one */
  			if (new->version < (*prev)->version) {

  				dbg_dentlist("Eep! Marking new dirent node obsolete, old is \"%s\", ino #%u
  ",

  					(*prev)->name, (*prev)->ino);

  				jffs2_mark_node_obsolete(c, new->raw);
  				jffs2_free_full_dirent(new);
  			} else {

  				dbg_dentlist("marking old dirent \"%s\", ino #%u obsolete
  ",

  					(*prev)->name, (*prev)->ino);

  				new->next = (*prev)->next;

  				/* It may have been a 'placeholder' deletion dirent, 
  				   if jffs2_can_mark_obsolete() (see jffs2_do_unlink()) */
  				if ((*prev)->raw)
  					jffs2_mark_node_obsolete(c, ((*prev)->raw));

  				jffs2_free_full_dirent(*prev);
  				*prev = new;
  			}

  			return;

  		}
  		prev = &((*prev)->next);
  	}
  	new->next = *prev;
  	*prev = new;

  }

  uint32_t jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint32_t size)

  {
  	struct jffs2_node_frag *frag = jffs2_lookup_node_frag(list, size);

  	dbg_fragtree("truncating fragtree to 0x%08x bytes
  ", size);

  
  	/* We know frag->ofs <= size. That's what lookup does for us */
  	if (frag && frag->ofs != size) {

  		if (frag->ofs+frag->size > size) {

  			frag->size = size - frag->ofs;
  		}
  		frag = frag_next(frag);
  	}
  	while (frag && frag->ofs >= size) {
  		struct jffs2_node_frag *next = frag_next(frag);

  		frag_erase(frag, list);
  		jffs2_obsolete_node_frag(c, frag);
  		frag = next;
  	}

  
  	if (size == 0)

  		return 0;

  	frag = frag_last(list);

  
  	/* Sanity check for truncation to longer than we started with... */
  	if (!frag)
  		return 0;
  	if (frag->ofs + frag->size < size)
  		return frag->ofs + frag->size;
  
  	/* If the last fragment starts at the RAM page boundary, it is
  	 * REF_PRISTINE irrespective of its size. */

  	if (frag->node && (frag->ofs & (PAGE_CACHE_SIZE - 1)) == 0) {

  		dbg_fragtree2("marking the last fragment 0x%08x-0x%08x REF_PRISTINE.
  ",

  			frag->ofs, frag->ofs + frag->size);

  		frag->node->raw->flash_offset = ref_offset(frag->node->raw) | REF_PRISTINE;
  	}

  	return size;

  }

  static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
  				     struct jffs2_node_frag *this)

  {

  	if (this->node) {
  		this->node->frags--;
  		if (!this->node->frags) {
  			/* The node has no valid frags left. It's totally obsoleted */

  			dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) obsolete
  ",

  				ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size);

  			jffs2_mark_node_obsolete(c, this->node->raw);
  			jffs2_free_full_dnode(this->node);
  		} else {

  			dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) REF_NORMAL. frags is %d
  ",

  				ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size, this->node->frags);

  			mark_ref_normal(this->node->raw);
  		}

  	}
  	jffs2_free_node_frag(this);

  }

  static void jffs2_fragtree_insert(struct jffs2_node_frag *newfrag, struct jffs2_node_frag *base)

  {

  	struct rb_node *parent = &base->rb;
  	struct rb_node **link = &parent;

  	dbg_fragtree2("insert frag (0x%04x-0x%04x)
  ", newfrag->ofs, newfrag->ofs + newfrag->size);

  	while (*link) {
  		parent = *link;
  		base = rb_entry(parent, struct jffs2_node_frag, rb);

  		if (newfrag->ofs > base->ofs)
  			link = &base->rb.rb_right;
  		else if (newfrag->ofs < base->ofs)
  			link = &base->rb.rb_left;

  		else {

  			JFFS2_ERROR("duplicate frag at %08x (%p,%p)
  ", newfrag->ofs, newfrag, base);

  			BUG();

  		}

  	}

  
  	rb_link_node(&newfrag->rb, &base->rb, link);

  }

  /*
   * Allocate and initializes a new fragment.
   */

  static struct jffs2_node_frag * new_fragment(struct jffs2_full_dnode *fn, uint32_t ofs, uint32_t size)

  {
  	struct jffs2_node_frag *newfrag;

  	newfrag = jffs2_alloc_node_frag();
  	if (likely(newfrag)) {
  		newfrag->ofs = ofs;
  		newfrag->size = size;
  		newfrag->node = fn;
  	} else {
  		JFFS2_ERROR("cannot allocate a jffs2_node_frag object
  ");
  	}
  
  	return newfrag;
  }
  
  /*
   * Called when there is no overlapping fragment exist. Inserts a hole before the new
   * fragment and inserts the new fragment to the fragtree.
   */
  static int no_overlapping_node(struct jffs2_sb_info *c, struct rb_root *root,
  		 	       struct jffs2_node_frag *newfrag,
  			       struct jffs2_node_frag *this, uint32_t lastend)
  {
  	if (lastend < newfrag->node->ofs) {
  		/* put a hole in before the new fragment */
  		struct jffs2_node_frag *holefrag;
  
  		holefrag= new_fragment(NULL, lastend, newfrag->node->ofs - lastend);
  		if (unlikely(!holefrag)) {
  			jffs2_free_node_frag(newfrag);
  			return -ENOMEM;
  		}
  
  		if (this) {

  			/* By definition, the 'this' node has no right-hand child,

  			   because there are no frags with offset greater than it.
  			   So that's where we want to put the hole */

  			dbg_fragtree2("add hole frag %#04x-%#04x on the right of the new frag.
  ",

  				holefrag->ofs, holefrag->ofs + holefrag->size);
  			rb_link_node(&holefrag->rb, &this->rb, &this->rb.rb_right);
  		} else {

  			dbg_fragtree2("Add hole frag %#04x-%#04x to the root of the tree.
  ",

  				holefrag->ofs, holefrag->ofs + holefrag->size);
  			rb_link_node(&holefrag->rb, NULL, &root->rb_node);
  		}
  		rb_insert_color(&holefrag->rb, root);
  		this = holefrag;
  	}

  	if (this) {

  		/* By definition, the 'this' node has no right-hand child,

  		   because there are no frags with offset greater than it.
  		   So that's where we want to put new fragment */

  		dbg_fragtree2("add the new node at the right
  ");

  		rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right);

  	} else {

  		dbg_fragtree2("insert the new node at the root of the tree
  ");

  		rb_link_node(&newfrag->rb, NULL, &root->rb_node);
  	}
  	rb_insert_color(&newfrag->rb, root);
  
  	return 0;
  }

  /* Doesn't set inode->i_size */

  static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *root, struct jffs2_node_frag *newfrag)

  {

  	struct jffs2_node_frag *this;
  	uint32_t lastend;

  	/* Skip all the nodes which are completed before this one starts */

  	this = jffs2_lookup_node_frag(root, newfrag->node->ofs);

  	if (this) {

  		dbg_fragtree2("lookup gave frag 0x%04x-0x%04x; phys 0x%08x (*%p)
  ",

  			  this->ofs, this->ofs+this->size, this->node?(ref_offset(this->node->raw)):0xffffffff, this);

  		lastend = this->ofs + this->size;
  	} else {

  		dbg_fragtree2("lookup gave no frag
  ");

  		lastend = 0;

  	}

  	/* See if we ran off the end of the fragtree */

  	if (lastend <= newfrag->ofs) {
  		/* We did */
  
  		/* Check if 'this' node was on the same page as the new node.
  		   If so, both 'this' and the new node get marked REF_NORMAL so
  		   the GC can take a look.
  		*/
  		if (lastend && (lastend-1) >> PAGE_CACHE_SHIFT == newfrag->ofs >> PAGE_CACHE_SHIFT) {
  			if (this->node)
  				mark_ref_normal(this->node->raw);
  			mark_ref_normal(newfrag->node->raw);
  		}

  		return no_overlapping_node(c, root, newfrag, this, lastend);

  	}

  	if (this->node)

  		dbg_fragtree2("dealing with frag %u-%u, phys %#08x(%d).
  ",

  		this->ofs, this->ofs + this->size,
  		ref_offset(this->node->raw), ref_flags(this->node->raw));
  	else

  		dbg_fragtree2("dealing with hole frag %u-%u.
  ",

  		this->ofs, this->ofs + this->size);

  	/* OK. 'this' is pointing at the first frag that newfrag->ofs at least partially obsoletes,

  	 * - i.e. newfrag->ofs < this->ofs+this->size && newfrag->ofs >= this->ofs

  	 */

  	if (newfrag->ofs > this->ofs) {
  		/* This node isn't completely obsoleted. The start of it remains valid */
  
  		/* Mark the new node and the partially covered node REF_NORMAL -- let
  		   the GC take a look at them */
  		mark_ref_normal(newfrag->node->raw);
  		if (this->node)
  			mark_ref_normal(this->node->raw);
  
  		if (this->ofs + this->size > newfrag->ofs + newfrag->size) {
  			/* The new node splits 'this' frag into two */

  			struct jffs2_node_frag *newfrag2;

  			if (this->node)

  				dbg_fragtree2("split old frag 0x%04x-0x%04x, phys 0x%08x
  ",

  					this->ofs, this->ofs+this->size, ref_offset(this->node->raw));

  			else

  				dbg_fragtree2("split old hole frag 0x%04x-0x%04x
  ",

  					this->ofs, this->ofs+this->size);

  			/* New second frag pointing to this's node */

  			newfrag2 = new_fragment(this->node, newfrag->ofs + newfrag->size,
  						this->ofs + this->size - newfrag->ofs - newfrag->size);
  			if (unlikely(!newfrag2))
  				return -ENOMEM;

  			if (this->node)
  				this->node->frags++;
  
  			/* Adjust size of original 'this' */
  			this->size = newfrag->ofs - this->ofs;
  
  			/* Now, we know there's no node with offset
  			   greater than this->ofs but smaller than
  			   newfrag2->ofs or newfrag->ofs, for obvious
  			   reasons. So we can do a tree insert from
  			   'this' to insert newfrag, and a tree insert
  			   from newfrag to insert newfrag2. */
  			jffs2_fragtree_insert(newfrag, this);

  			rb_insert_color(&newfrag->rb, root);

  			jffs2_fragtree_insert(newfrag2, newfrag);

  			rb_insert_color(&newfrag2->rb, root);

  			return 0;

  		}

  		/* New node just reduces 'this' frag in size, doesn't split it */
  		this->size = newfrag->ofs - this->ofs;

  		/* Again, we know it lives down here in the tree */
  		jffs2_fragtree_insert(newfrag, this);

  		rb_insert_color(&newfrag->rb, root);

  	} else {

  		/* New frag starts at the same point as 'this' used to. Replace

  		   it in the tree without doing a delete and insertion */

  		dbg_fragtree2("inserting newfrag (*%p),%d-%d in before 'this' (*%p),%d-%d
  ",

  			  newfrag, newfrag->ofs, newfrag->ofs+newfrag->size, this, this->ofs, this->ofs+this->size);

  		rb_replace_node(&this->rb, &newfrag->rb, root);

  		if (newfrag->ofs + newfrag->size >= this->ofs+this->size) {

  			dbg_fragtree2("obsoleting node frag %p (%x-%x)
  ", this, this->ofs, this->ofs+this->size);

  			jffs2_obsolete_node_frag(c, this);

  		} else {

  			this->ofs += newfrag->size;
  			this->size -= newfrag->size;
  
  			jffs2_fragtree_insert(this, newfrag);

  			rb_insert_color(&this->rb, root);

  			return 0;

  		}

  	}

  	/* OK, now we have newfrag added in the correct place in the tree, but

  	   frag_next(newfrag) may be a fragment which is overlapped by it

  	*/
  	while ((this = frag_next(newfrag)) && newfrag->ofs + newfrag->size >= this->ofs + this->size) {
  		/* 'this' frag is obsoleted completely. */

  		dbg_fragtree2("obsoleting node frag %p (%x-%x) and removing from tree
  ",

  			this, this->ofs, this->ofs+this->size);

  		rb_erase(&this->rb, root);

  		jffs2_obsolete_node_frag(c, this);

  	}

  	/* Now we're pointing at the first frag which isn't totally obsoleted by

  	   the new frag */

  	if (!this || newfrag->ofs + newfrag->size == this->ofs)

  		return 0;

  	/* Still some overlap but we don't need to move it in the tree */
  	this->size = (this->ofs + this->size) - (newfrag->ofs + newfrag->size);
  	this->ofs = newfrag->ofs + newfrag->size;
  
  	/* And mark them REF_NORMAL so the GC takes a look at them */
  	if (this->node)
  		mark_ref_normal(this->node->raw);
  	mark_ref_normal(newfrag->node->raw);

  
  	return 0;
  }

  /*

   * Given an inode, probably with existing tree of fragments, add the new node
   * to the fragment tree.

   */

  int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn)

  {

  	int ret;
  	struct jffs2_node_frag *newfrag;

  	if (unlikely(!fn->size))
  		return 0;

  	newfrag = new_fragment(fn, fn->ofs, fn->size);

  	if (unlikely(!newfrag))
  		return -ENOMEM;

  	newfrag->node->frags = 1;

  	dbg_fragtree("adding node %#04x-%#04x @0x%08x on flash, newfrag *%p
  ",

  		  fn->ofs, fn->ofs+fn->size, ref_offset(fn->raw), newfrag);

  	ret = jffs2_add_frag_to_fragtree(c, &f->fragtree, newfrag);
  	if (unlikely(ret))
  		return ret;
  
  	/* If we now share a page with other nodes, mark either previous
  	   or next node REF_NORMAL, as appropriate.  */
  	if (newfrag->ofs & (PAGE_CACHE_SIZE-1)) {
  		struct jffs2_node_frag *prev = frag_prev(newfrag);
  
  		mark_ref_normal(fn->raw);

  		/* If we don't start at zero there's _always_ a previous */

  		if (prev->node)
  			mark_ref_normal(prev->node->raw);
  	}

  	if ((newfrag->ofs+newfrag->size) & (PAGE_CACHE_SIZE-1)) {
  		struct jffs2_node_frag *next = frag_next(newfrag);

  		if (next) {
  			mark_ref_normal(fn->raw);
  			if (next->node)
  				mark_ref_normal(next->node->raw);

  		}

  	}

  	jffs2_dbg_fragtree_paranoia_check_nolock(f);

  
  	return 0;
  }

  void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state)
  {
  	spin_lock(&c->inocache_lock);
  	ic->state = state;
  	wake_up(&c->inocache_wq);
  	spin_unlock(&c->inocache_lock);
  }
  
  /* During mount, this needs no locking. During normal operation, its
     callers want to do other stuff while still holding the inocache_lock.

     Rather than introducing special case get_ino_cache functions or

     callbacks, we just let the caller do the locking itself. */

  struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
  {
  	struct jffs2_inode_cache *ret;

  	ret = c->inocache_list[ino % c->inocache_hashsize];

  	while (ret && ret->ino < ino) {
  		ret = ret->next;
  	}

  	if (ret && ret->ino != ino)
  		ret = NULL;

  	return ret;
  }
  
  void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new)
  {
  	struct jffs2_inode_cache **prev;

  	spin_lock(&c->inocache_lock);

  	if (!new->ino)
  		new->ino = ++c->highest_ino;

  	dbg_inocache("add %p (ino #%u)
  ", new, new->ino);

  	prev = &c->inocache_list[new->ino % c->inocache_hashsize];

  
  	while ((*prev) && (*prev)->ino < new->ino) {
  		prev = &(*prev)->next;
  	}
  	new->next = *prev;
  	*prev = new;
  
  	spin_unlock(&c->inocache_lock);
  }
  
  void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old)
  {
  	struct jffs2_inode_cache **prev;

  #ifdef CONFIG_JFFS2_FS_XATTR
  	BUG_ON(old->xref);
  #endif

  	dbg_inocache("del %p (ino #%u)
  ", old, old->ino);

  	spin_lock(&c->inocache_lock);

  	prev = &c->inocache_list[old->ino % c->inocache_hashsize];

  	while ((*prev) && (*prev)->ino < old->ino) {
  		prev = &(*prev)->next;
  	}
  	if ((*prev) == old) {
  		*prev = old->next;
  	}

  	/* Free it now unless it's in READING or CLEARING state, which
  	   are the transitions upon read_inode() and clear_inode(). The

  	   rest of the time we know nobody else is looking at it, and

  	   if it's held by read_inode() or clear_inode() they'll free it
  	   for themselves. */
  	if (old->state != INO_STATE_READING && old->state != INO_STATE_CLEARING)
  		jffs2_free_inode_cache(old);

  	spin_unlock(&c->inocache_lock);
  }
  
  void jffs2_free_ino_caches(struct jffs2_sb_info *c)
  {
  	int i;
  	struct jffs2_inode_cache *this, *next;

  	for (i=0; i < c->inocache_hashsize; i++) {

  		this = c->inocache_list[i];
  		while (this) {
  			next = this->next;

  			jffs2_xattr_free_inode(c, this);

  			jffs2_free_inode_cache(this);
  			this = next;
  		}
  		c->inocache_list[i] = NULL;
  	}
  }
  
  void jffs2_free_raw_node_refs(struct jffs2_sb_info *c)
  {
  	int i;
  	struct jffs2_raw_node_ref *this, *next;
  
  	for (i=0; i<c->nr_blocks; i++) {
  		this = c->blocks[i].first_node;

  		while (this) {

  			if (this[REFS_PER_BLOCK].flash_offset == REF_LINK_NODE)
  				next = this[REFS_PER_BLOCK].next_in_ino;
  			else
  				next = NULL;
  
  			jffs2_free_refblock(this);

  			this = next;
  		}
  		c->blocks[i].first_node = c->blocks[i].last_node = NULL;
  	}
  }

  struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset)
  {

  	/* The common case in lookup is that there will be a node

  	   which precisely matches. So we go looking for that first */
  	struct rb_node *next;
  	struct jffs2_node_frag *prev = NULL;
  	struct jffs2_node_frag *frag = NULL;

  	dbg_fragtree2("root %p, offset %d
  ", fragtree, offset);

  
  	next = fragtree->rb_node;
  
  	while(next) {
  		frag = rb_entry(next, struct jffs2_node_frag, rb);

  		if (frag->ofs + frag->size <= offset) {

  			/* Remember the closest smaller match on the way down */
  			if (!prev || frag->ofs > prev->ofs)
  				prev = frag;
  			next = frag->rb.rb_right;
  		} else if (frag->ofs > offset) {

  			next = frag->rb.rb_left;
  		} else {

  			return frag;
  		}
  	}
  
  	/* Exact match not found. Go back up looking at each parent,
  	   and return the closest smaller one */
  
  	if (prev)

  		dbg_fragtree2("no match. Returning frag %#04x-%#04x, closest previous
  ",

  			  prev->ofs, prev->ofs+prev->size);

  	else

  		dbg_fragtree2("returning NULL, empty fragtree
  ");

  	return prev;
  }
  
  /* Pass 'c' argument to indicate that nodes should be marked obsolete as
     they're killed. */
  void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c)
  {
  	struct jffs2_node_frag *frag;
  	struct jffs2_node_frag *parent;
  
  	if (!root->rb_node)
  		return;

  	dbg_fragtree("killing
  ");

  	frag = (rb_entry(root->rb_node, struct jffs2_node_frag, rb));

  	while(frag) {
  		if (frag->rb.rb_left) {

  			frag = frag_left(frag);
  			continue;
  		}
  		if (frag->rb.rb_right) {

  			frag = frag_right(frag);
  			continue;
  		}

  		if (frag->node && !(--frag->node->frags)) {

  			/* Not a hole, and it's the final remaining frag

  			   of this node. Free the node */
  			if (c)
  				jffs2_mark_node_obsolete(c, frag->node->raw);

  			jffs2_free_full_dnode(frag->node);
  		}
  		parent = frag_parent(frag);
  		if (parent) {
  			if (frag_left(parent) == frag)
  				parent->rb.rb_left = NULL;

  			else

  				parent->rb.rb_right = NULL;
  		}
  
  		jffs2_free_node_frag(frag);
  		frag = parent;
  
  		cond_resched();
  	}
  }

  struct jffs2_raw_node_ref *jffs2_link_node_ref(struct jffs2_sb_info *c,
  					       struct jffs2_eraseblock *jeb,
  					       uint32_t ofs, uint32_t len,
  					       struct jffs2_inode_cache *ic)

  {

  	struct jffs2_raw_node_ref *ref;

  	BUG_ON(!jeb->allocated_refs);
  	jeb->allocated_refs--;
  
  	ref = jeb->last_node;
  
  	dbg_noderef("Last node at %p is (%08x,%p)
  ", ref, ref->flash_offset,
  		    ref->next_in_ino);
  
  	while (ref->flash_offset != REF_EMPTY_NODE) {
  		if (ref->flash_offset == REF_LINK_NODE)
  			ref = ref->next_in_ino;
  		else
  			ref++;

  	}

  	dbg_noderef("New ref is %p (%08x becomes %08x,%p) len 0x%x
  ", ref, 
  		    ref->flash_offset, ofs, ref->next_in_ino, len);

  	ref->flash_offset = ofs;

  	if (!jeb->first_node) {

  		jeb->first_node = ref;

  		BUG_ON(ref_offset(ref) != jeb->offset);
  	} else if (unlikely(ref_offset(ref) != jeb->offset + c->sector_size - jeb->free_size)) {
  		uint32_t last_len = ref_totlen(c, jeb, jeb->last_node);
  
  		JFFS2_ERROR("Adding new ref %p at (0x%08x-0x%08x) not immediately after previous (0x%08x-0x%08x)
  ",
  			    ref, ref_offset(ref), ref_offset(ref)+len,
  			    ref_offset(jeb->last_node), 
  			    ref_offset(jeb->last_node)+last_len);
  		BUG();

  	}

  	jeb->last_node = ref;

  	if (ic) {
  		ref->next_in_ino = ic->nodes;
  		ic->nodes = ref;
  	} else {
  		ref->next_in_ino = NULL;
  	}

  	switch(ref_flags(ref)) {
  	case REF_UNCHECKED:
  		c->unchecked_size += len;
  		jeb->unchecked_size += len;
  		break;
  
  	case REF_NORMAL:
  	case REF_PRISTINE:
  		c->used_size += len;
  		jeb->used_size += len;
  		break;
  
  	case REF_OBSOLETE:
  		c->dirty_size += len;

  		jeb->dirty_size += len;

  		break;
  	}
  	c->free_size -= len;
  	jeb->free_size -= len;

  #ifdef TEST_TOTLEN
  	/* Set (and test) __totlen field... for now */
  	ref->__totlen = len;
  	ref_totlen(c, jeb, ref);
  #endif

  	return ref;

  }

  /* No locking, no reservation of 'ref'. Do not use on a live file system */

  int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
  			   uint32_t size)
  {

  	if (!size)
  		return 0;

  	if (unlikely(size > jeb->free_size)) {
  		printk(KERN_CRIT "Dirty space 0x%x larger then free_size 0x%x (wasted 0x%x)
  ",
  		       size, jeb->free_size, jeb->wasted_size);

  		BUG();
  	}

  	/* REF_EMPTY_NODE is !obsolete, so that works OK */

  	if (jeb->last_node && ref_obsolete(jeb->last_node)) {

  #ifdef TEST_TOTLEN
  		jeb->last_node->__totlen += size;
  #endif
  		c->dirty_size += size;
  		c->free_size -= size;
  		jeb->dirty_size += size;
  		jeb->free_size -= size;
  	} else {

  		uint32_t ofs = jeb->offset + c->sector_size - jeb->free_size;
  		ofs |= REF_OBSOLETE;

  		jffs2_link_node_ref(c, jeb, ofs, size, NULL);

  	}

  
  	return 0;
  }

  
  /* Calculate totlen from surrounding nodes or eraseblock */
  static inline uint32_t __ref_totlen(struct jffs2_sb_info *c,
  				    struct jffs2_eraseblock *jeb,
  				    struct jffs2_raw_node_ref *ref)
  {
  	uint32_t ref_end;

  	struct jffs2_raw_node_ref *next_ref = ref_next(ref);

  	if (next_ref)
  		ref_end = ref_offset(next_ref);

  	else {
  		if (!jeb)
  			jeb = &c->blocks[ref->flash_offset / c->sector_size];
  
  		/* Last node in block. Use free_space */

  		if (unlikely(ref != jeb->last_node)) {

  			printk(KERN_CRIT "ref %p @0x%08x is not jeb->last_node (%p @0x%08x)
  ",
  			       ref, ref_offset(ref), jeb->last_node, jeb->last_node?ref_offset(jeb->last_node):0);
  			BUG();
  		}
  		ref_end = jeb->offset + c->sector_size - jeb->free_size;
  	}
  	return ref_end - ref_offset(ref);
  }
  
  uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
  			    struct jffs2_raw_node_ref *ref)
  {
  	uint32_t ret;

  	ret = __ref_totlen(c, jeb, ref);

  #ifdef TEST_TOTLEN

  	if (unlikely(ret != ref->__totlen)) {
  		if (!jeb)
  			jeb = &c->blocks[ref->flash_offset / c->sector_size];

  		printk(KERN_CRIT "Totlen for ref at %p (0x%08x-0x%08x) miscalculated as 0x%x instead of %x
  ",
  		       ref, ref_offset(ref), ref_offset(ref)+ref->__totlen,
  		       ret, ref->__totlen);

  		if (ref_next(ref)) {
  			printk(KERN_CRIT "next %p (0x%08x-0x%08x)
  ", ref_next(ref), ref_offset(ref_next(ref)),
  			       ref_offset(ref_next(ref))+ref->__totlen);

  		} else 

  			printk(KERN_CRIT "No next ref. jeb->last_node is %p
  ", jeb->last_node);

  
  		printk(KERN_CRIT "jeb->wasted_size %x, dirty_size %x, used_size %x, free_size %x
  ", jeb->wasted_size, jeb->dirty_size, jeb->used_size, jeb->free_size);

  #if defined(JFFS2_DBG_DUMPS) || defined(JFFS2_DBG_PARANOIA_CHECKS)
  		__jffs2_dbg_dump_node_refs_nolock(c, jeb);
  #endif

  		WARN_ON(1);

  
  		ret = ref->__totlen;

  	}
  #endif /* TEST_TOTLEN */
  	return ret;
  }