1 files changed, 570 insertions, 67 deletions

diff --git a/fs/jffs2/nodelist.c b/fs/jffs2/nodelist.c
index 0cf5e6f11989..390ce06ab1a7 100644
--- a/fs/jffs2/nodelist.c
+++ b/fs/jffs2/nodelist.c
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: nodelist.c,v 1.103 2005/07/31 08:20:44 dedekind Exp $
+ * $Id: nodelist.c,v 1.104 2005/08/01 12:05:19 dedekind Exp $
  *
  */
 
@@ -59,7 +59,7 @@ void jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint
 
 	/* We know frag->ofs <= size. That's what lookup does for us */
 	if (frag && frag->ofs != size) {
-		if (frag->ofs+frag->size >= size) {
+		if (frag->ofs+frag->size > size) {
 			JFFS2_DBG_FRAGTREE2("truncating frag 0x%08x-0x%08x\n", frag->ofs, frag->ofs+frag->size);
 			frag->size = size - frag->ofs;
 		}
@@ -73,6 +73,20 @@ void jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint
 		jffs2_obsolete_node_frag(c, frag);
 		frag = next;
 	}
+
+	if (size == 0)
+		return;
+
+	/* 
+	 * If the last fragment starts at the RAM page boundary, it is
+	 * REF_PRISTINE irrespective of its size.
+	 */
+	frag = frag_last(list);
+	if ((frag->ofs & (PAGE_CACHE_SIZE - 1)) == 0) {
+		JFFS2_DBG_FRAGTREE2("marking the last fragment 0x%08x-0x%08x REF_PRISTINE.\n",
+			frag->ofs, frag->ofs + frag->size); 
+		frag->node->raw->flash_offset = ref_offset(frag->node->raw) | REF_PRISTINE;
+	}
 }
 
 void jffs2_obsolete_node_frag(struct jffs2_sb_info *c, struct jffs2_node_frag *this)
@@ -120,14 +134,82 @@ static void jffs2_fragtree_insert(struct jffs2_node_frag *newfrag, struct jffs2_
 	rb_link_node(&newfrag->rb, &base->rb, link);
 }
 
+/*
+ * Allocate and initializes a new fragment.
+ */
+static inline 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\n");
+	}
+
+	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 */
+			JFFS2_DBG_FRAGTREE2("add hole frag %u-%u on the right of the new frag.\n",
+				holefrag->ofs, holefrag->ofs + holefrag->size);
+			rb_link_node(&holefrag->rb, &this->rb, &this->rb.rb_right);
+		} else {
+			JFFS2_DBG_FRAGTREE2("Add hole frag %u-%u to the root of the tree.\n",
+				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 */
+		JFFS2_DBG_FRAGTREE2("add the new node at the right\n");
+		rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right);			
+	} else {
+		JFFS2_DBG_FRAGTREE2("insert the new node at the root of the tree\n");
+		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 *list, struct jffs2_node_frag *newfrag)
+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(list, newfrag->node->ofs);
+	this = jffs2_lookup_node_frag(root, newfrag->node->ofs);
 
 	if (this) {
 		JFFS2_DBG_FRAGTREE2("lookup gave frag 0x%04x-0x%04x; phys 0x%08x (*%p)\n",
@@ -138,7 +220,7 @@ static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *l
 		lastend = 0;
 	}
 			  
-	/* See if we ran off the end of the list */
+	/* See if we ran off the end of the fragtree */
 	if (lastend <= newfrag->ofs) {
 		/* We did */
 
@@ -152,45 +234,16 @@ static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *l
 			mark_ref_normal(newfrag->node->raw);
 		}
 
-		if (lastend < newfrag->node->ofs) {
-			/* ... and we need to put a hole in before the new node */
-			struct jffs2_node_frag *holefrag = jffs2_alloc_node_frag();
-			if (!holefrag) {
-				jffs2_free_node_frag(newfrag);
-				return -ENOMEM;
-			}
-			holefrag->ofs = lastend;
-			holefrag->size = newfrag->node->ofs - lastend;
-			holefrag->node = NULL;
-			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 */
-				JFFS2_DBG_FRAGTREE2("adding hole frag (%p) on right of node at (%p)\n", holefrag, this);
-				rb_link_node(&holefrag->rb, &this->rb, &this->rb.rb_right);
-			} else {
-				JFFS2_DBG_FRAGTREE2("adding hole frag (%p) at root of tree\n", holefrag);
-				rb_link_node(&holefrag->rb, NULL, &list->rb_node);
-			}
-			rb_insert_color(&holefrag->rb, list);
-			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 */
-			JFFS2_DBG_FRAGTREE2("adding new frag (%p) on right of node at (%p)\n", newfrag, this);
-			rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right);			
-		} else {
-			JFFS2_DBG_FRAGTREE2("adding new frag (%p) at root of tree\n", newfrag);
-			rb_link_node(&newfrag->rb, NULL, &list->rb_node);
-		}
-		rb_insert_color(&newfrag->rb, list);
-		return 0;
+		return no_overlapping_node(c, root, newfrag, this, lastend);
 	}
 
-	JFFS2_DBG_FRAGTREE2("dealing with frag 0x%04x-0x%04x; phys 0x%08x (*%p)\n", 
-		  this->ofs, this->ofs+this->size, this->node?(ref_offset(this->node->raw)):0xffffffff, this);
+	if (this->node)
+		JFFS2_DBG_FRAGTREE2("dealing with frag %u-%u, phys %#08x(%d).\n",
+		this->ofs, this->ofs + this->size,
+		ref_offset(this->node->raw), ref_flags(this->node->raw));
+	else
+		JFFS2_DBG_FRAGTREE2("dealing with hole frag %u-%u.\n",
+		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  
@@ -206,11 +259,8 @@ static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *l
 
 		if (this->ofs + this->size > newfrag->ofs + newfrag->size) {
 			/* The new node splits 'this' frag into two */
-			struct jffs2_node_frag *newfrag2 = jffs2_alloc_node_frag();
-			if (!newfrag2) {
-				jffs2_free_node_frag(newfrag);
-				return -ENOMEM;
-			}
+			struct jffs2_node_frag *newfrag2;
+
 			if (this->node)
 				JFFS2_DBG_FRAGTREE2("split old frag 0x%04x-0x%04x, phys 0x%08x\n",
 					this->ofs, this->ofs+this->size, ref_offset(this->node->raw));
@@ -219,9 +269,10 @@ static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *l
 					this->ofs, this->ofs+this->size, ref_offset(this->node->raw));
 			
 			/* New second frag pointing to this's node */
-			newfrag2->ofs = newfrag->ofs + newfrag->size;
-			newfrag2->size = (this->ofs+this->size) - newfrag2->ofs;
-			newfrag2->node = this->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++;
 
@@ -235,10 +286,10 @@ static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *l
 			   'this' to insert newfrag, and a tree insert
 			   from newfrag to insert newfrag2. */
 			jffs2_fragtree_insert(newfrag, this);
-			rb_insert_color(&newfrag->rb, list);
+			rb_insert_color(&newfrag->rb, root);
 			
 			jffs2_fragtree_insert(newfrag2, newfrag);
-			rb_insert_color(&newfrag2->rb, list);
+			rb_insert_color(&newfrag2->rb, root);
 			
 			return 0;
 		}
@@ -247,14 +298,14 @@ static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *l
 
 		/* Again, we know it lives down here in the tree */
 		jffs2_fragtree_insert(newfrag, this);
-		rb_insert_color(&newfrag->rb, list);
+		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 */
 		JFFS2_DBG_FRAGTREE2("inserting newfrag (*%p),%d-%d in before 'this' (*%p),%d-%d\n",
 			  newfrag, newfrag->ofs, newfrag->ofs+newfrag->size, this, this->ofs, this->ofs+this->size);
 	
-		rb_replace_node(&this->rb, &newfrag->rb, list);
+		rb_replace_node(&this->rb, &newfrag->rb, root);
 		
 		if (newfrag->ofs + newfrag->size >= this->ofs+this->size) {
 			JFFS2_DBG_FRAGTREE2("obsoleting node frag %p (%x-%x)\n", this, this->ofs, this->ofs+this->size);
@@ -264,7 +315,7 @@ static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *l
 			this->size -= newfrag->size;
 
 			jffs2_fragtree_insert(this, newfrag);
-			rb_insert_color(&this->rb, list);
+			rb_insert_color(&this->rb, root);
 			return 0;
 		}
 	}
@@ -275,15 +326,15 @@ static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *l
 		/* 'this' frag is obsoleted completely. */
 		JFFS2_DBG_FRAGTREE2("obsoleting node frag %p (%x-%x) and removing from tree\n",
 			this, this->ofs, this->ofs+this->size);
-		rb_erase(&this->rb, list);
+		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) {
+	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;
@@ -296,8 +347,9 @@ static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *l
 	return 0;
 }
 
-/* Given an inode, probably with existing list of fragments, add the new node
- * to the fragment list.
+/* 
+ * 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)
 {
@@ -307,18 +359,14 @@ int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_in
 	if (unlikely(!fn->size))
 		return 0;
 
-	newfrag = jffs2_alloc_node_frag();
+	newfrag = new_fragment(fn, fn->ofs, fn->size);
 	if (unlikely(!newfrag))
 		return -ENOMEM;
+	newfrag->node->frags = 1;
 
 	JFFS2_DBG_FRAGTREE("adding node %#04x-%#04x @0x%08x on flash, newfrag *%p\n",
 		  fn->ofs, fn->ofs+fn->size, ref_offset(fn->raw), newfrag);
 	
-	newfrag->ofs = fn->ofs;
-	newfrag->size = fn->size;
-	newfrag->node = fn;
-	newfrag->node->frags = 1;
-
 	ret = jffs2_add_frag_to_fragtree(c, &f->fragtree, newfrag);
 	if (unlikely(ret))
 		return ret;
@@ -344,10 +392,465 @@ int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_in
 		}
 	}
 	jffs2_dbg_fragtree_paranoia_check_nolock(f);
-	jffs2_dbg_dump_fragtree_nolock(f);
+
+	return 0;
+}
+
+/*
+ * Check the data CRC of the node.
+ *
+ * Returns: 0 if the data CRC is correct;
+ * 	    1 - if incorrect;
+ *	    error code if an error occured.
+ */
+static int check_node_data(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn)
+{
+	struct jffs2_raw_node_ref *ref = tn->fn->raw;
+	int err = 0, pointed = 0;
+	struct jffs2_eraseblock *jeb;
+	unsigned char *buffer;
+	uint32_t crc, ofs, retlen, len;
+
+	BUG_ON(tn->csize == 0);
+
+	/* Calculate how many bytes were already checked */
+	ofs = ref_offset(ref) + sizeof(struct jffs2_raw_inode);
+	len = ofs - (ofs & (PAGE_CACHE_SIZE - 1));
+	len = c->wbuf_pagesize - len;
+
+	if (len >= tn->csize) {
+		JFFS2_DBG_READINODE("no need to check node at %#08x, data length %u, data starts at %#08x - it has already been checked.\n",
+			ref_offset(ref), tn->csize, ofs);
+		goto adj_acc;
+	}
+	
+	ofs += len;
+	len = tn->csize - len;
+	
+	JFFS2_DBG_READINODE("check node at %#08x, data length %u, partial CRC %#08x, correct CRC %#08x, data starts at %#08x, start checking from %#08x - %u bytes.\n",
+		ref_offset(ref), tn->csize, tn->partial_crc, tn->data_crc, ofs - len, ofs, len);
+	
+#ifndef __ECOS
+	/* TODO: instead, incapsulate point() stuff to jffs2_flash_read(),
+	 * adding and jffs2_flash_read_end() interface. */
+	if (c->mtd->point) {
+		err = c->mtd->point(c->mtd, ofs, len, &retlen, &buffer);
+		if (!err && retlen < tn->csize) {
+			JFFS2_WARNING("MTD point returned len too short: %u instead of %u.\n", retlen, tn->csize);
+			c->mtd->unpoint(c->mtd, buffer, ofs, len);
+		} else if (err)
+			JFFS2_WARNING("MTD point failed: error code %d.\n", err);
+		else
+			pointed = 1; /* succefully pointed to device */
+	}
+#endif
+	
+	if (!pointed) {
+		buffer = kmalloc(len, GFP_KERNEL);
+		if (unlikely(!buffer))
+			return -ENOMEM;
+			
+		/* TODO: this is very frequent pattern, make it a separate
+		 * routine */
+		err = jffs2_flash_read(c, ofs, len, &retlen, buffer);
+		if (err) {
+			JFFS2_ERROR("can not read %d bytes from 0x%08x, error code: %d.\n", len, ofs, err);
+			goto free_out;
+		}
+			
+		if (retlen != len) {
+			JFFS2_ERROR("short read at %#08x: %d instead of %d.\n", ofs, retlen, len);
+			err = -EIO;
+			goto free_out;
+		}
+	}
+
+	/* Continue calculating CRC */
+	crc = crc32(tn->partial_crc, buffer, len);
+	if(!pointed)
+		kfree(buffer);
+#ifndef __ECOS
+	else
+		c->mtd->unpoint(c->mtd, buffer, ofs, len);
+#endif
+
+	if (crc != tn->data_crc) {
+		JFFS2_NOTICE("drong data CRC in data node at 0x%08x: read %#08x, calculated %#08x.\n",
+			ofs, tn->data_crc, crc);
+		return 1;
+	}
+
+adj_acc:
+	jeb = &c->blocks[ref->flash_offset / c->sector_size];
+	len = ref_totlen(c, jeb, ref);
+
+	/* 
+	 * Mark the node as having been checked and fix the
+	 * accounting accordingly.
+	 */
+	spin_lock(&c->erase_completion_lock);
+	jeb->used_size += len;
+	jeb->unchecked_size -= len;
+	c->used_size += len;
+	c->unchecked_size -= len;
+	spin_unlock(&c->erase_completion_lock);
+
 	return 0;
+
+free_out:
+	if(!pointed)
+		kfree(buffer);
+#ifndef __ECOS
+	else
+		c->mtd->unpoint(c->mtd, buffer, ofs, len);
+#endif
+	return err;
 }
 
+/*
+ * Helper function for jffs2_add_older_frag_to_fragtree().
+ *
+ * Checks the node if we are in the checking stage.
+ */
+static inline int check_node(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_tmp_dnode_info *tn)
+{
+	int ret;
+	
+	BUG_ON(ref_obsolete(tn->fn->raw));
+
+	/* We only check the data CRC of unchecked nodes */
+	if (ref_flags(tn->fn->raw) != REF_UNCHECKED)
+		return 0;
+	
+	JFFS2_DBG_FRAGTREE2("check node %u-%u, phys offs %#08x.\n",
+		tn->fn->ofs, tn->fn->ofs + tn->fn->size,
+		ref_offset(tn->fn->raw));
+
+	ret = check_node_data(c, tn);
+	if (unlikely(ret < 0)) {
+		JFFS2_ERROR("check_node_data() returned error: %d.\n",
+			ret);
+	} else if (unlikely(ret > 0)) {
+		JFFS2_DBG_FRAGTREE2("CRC error, mark it obsolete.\n");
+		jffs2_mark_node_obsolete(c, tn->fn->raw);
+	}
+
+	return ret;
+}
+
+/* 
+ * Helper function for jffs2_add_older_frag_to_fragtree().
+ *
+ * Called when the new fragment that is being inserted
+ * splits a hole fragment.
+ */
+static int split_hole(struct jffs2_sb_info *c, struct rb_root *root,
+		      struct jffs2_node_frag *newfrag, struct jffs2_node_frag *hole)
+{
+	JFFS2_DBG_FRAGTREE2("fragment %#04x-%#04x splits the hole %#04x-%#04x\n",
+		newfrag->ofs, newfrag->ofs + newfrag->size, hole->ofs, hole->ofs + hole->size);
+
+	if (hole->ofs == newfrag->ofs) {
+		/* 
+		 * Well, the new fragment actually starts at the same offset as
+		 * the hole.
+		 */
+		if (hole->ofs + hole->size > newfrag->ofs + newfrag->size) {
+			/* 
+			 * We replace the overlapped left part of the hole by
+			 * the new node.
+			 */
+			
+			JFFS2_DBG_FRAGTREE2("insert fragment %#04x-%#04x and cut the left part of the hole\n",
+				newfrag->ofs, newfrag->ofs + newfrag->size);
+			rb_replace_node(&hole->rb, &newfrag->rb, root);
+			
+			hole->ofs += newfrag->size;
+			hole->size -= newfrag->size;
+			
+			/* 
+			 * We know that 'hole' should be the right hand
+			 * fragment.
+			 */
+			jffs2_fragtree_insert(hole, newfrag);
+			rb_insert_color(&hole->rb, root);
+		} else {
+			/* 
+			 * Ah, the new fragment is of the same size as the hole.
+			 * Relace the hole by it.
+			 */
+			JFFS2_DBG_FRAGTREE2("insert fragment %#04x-%#04x and overwrite hole\n",
+				newfrag->ofs, newfrag->ofs + newfrag->size);
+			rb_replace_node(&hole->rb, &newfrag->rb, root);
+			jffs2_free_node_frag(hole);
+		}
+	} else {
+		/* The new fragment lefts some hole space at the left */
+		
+		struct jffs2_node_frag * newfrag2 = NULL;
+
+		if (hole->ofs + hole->size > newfrag->ofs + newfrag->size) {
+			/* The new frag also lefts some space at the right */
+			newfrag2 = new_fragment(NULL, newfrag->ofs +
+				newfrag->size, hole->ofs + hole->size
+				- newfrag->ofs - newfrag->size);
+			if (unlikely(!newfrag2)) {
+				jffs2_free_node_frag(newfrag);
+				return -ENOMEM;
+			}
+		}
+
+		hole->size = newfrag->ofs - hole->ofs;
+		JFFS2_DBG_FRAGTREE2("left the hole %#04x-%#04x at the left and inserd fragment %#04x-%#04x\n",
+			hole->ofs, hole->ofs + hole->size, newfrag->ofs, newfrag->ofs + newfrag->size);
+
+		jffs2_fragtree_insert(newfrag, hole);
+		rb_insert_color(&newfrag->rb, root);
+		
+		if (newfrag2) {
+			JFFS2_DBG_FRAGTREE2("left the hole %#04x-%#04x at the right\n",
+				newfrag2->ofs, newfrag2->ofs + newfrag2->size);
+			jffs2_fragtree_insert(newfrag2, newfrag);
+			rb_insert_color(&newfrag2->rb, root);
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * This function is used when we build inode. It expects the nodes are passed
+ * in the decreasing version order. The whole point of this is to improve the
+ * inodes checking on NAND: we check the nodes' data CRC only when they are not
+ * obsoleted. Previously, add_frag_to_fragtree() function was used and
+ * nodes were passed to it in the increasing version ordes and CRCs of all
+ * nodes were checked.
+ *
+ * Note: tn->fn->size shouldn't be zero.
+ *
+ * Returns 0 if the node was inserted
+ *         1 if it wasn't inserted (since it is obsolete)
+ *         < 0 an if error occured
+ */
+int jffs2_add_older_frag_to_fragtree(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
+				     struct jffs2_tmp_dnode_info *tn)
+{
+	struct jffs2_node_frag *this, *newfrag;
+	uint32_t lastend;
+	struct jffs2_full_dnode *fn = tn->fn;
+	struct rb_root *root = &f->fragtree;
+	uint32_t fn_size = fn->size, fn_ofs = fn->ofs;
+	int err, checked = 0;
+	int ref_flag;
+
+	JFFS2_DBG_FRAGTREE("insert fragment %#04x-%#04x\n", fn_ofs, fn_ofs + fn_size);
+
+	/* Skip all the nodes which are completed before this one starts */
+	this = jffs2_lookup_node_frag(root, fn_ofs);
+	if (this)
+		JFFS2_DBG_FRAGTREE2("'this' found %#04x-%#04x (%s)\n", this->ofs, this->ofs + this->size, this->node ? "data" : "hole");
+
+	if (this)
+		lastend = this->ofs + this->size;
+	else
+		lastend = 0;
+	
+	/* Detect the preliminary type of node */
+	if (fn->size >= PAGE_CACHE_SIZE)
+		ref_flag = REF_PRISTINE;
+	else
+		ref_flag = REF_NORMAL;
+	
+	/* See if we ran off the end of the root */
+	if (lastend <= fn_ofs) {
+		/* We did */
+		
+		/* 
+		 * We are going to insert the new node into the
+		 * fragment tree, so check it.
+		 */
+		err = check_node(c, f, tn);
+		if (err != 0)
+			return err;
+
+		fn->frags = 1;
+
+		newfrag = new_fragment(fn, fn_ofs, fn_size);
+		if (unlikely(!newfrag))
+			return -ENOMEM;
+
+		err = no_overlapping_node(c, root, newfrag, this, lastend);
+		if (unlikely(err != 0)) {
+			jffs2_free_node_frag(newfrag);
+			return err;
+		}
+
+		goto out_ok;
+	}
+
+	fn->frags = 0;
+
+	while (1) {
+		/* 
+		 * Here we have:
+		 * fn_ofs < this->ofs + this->size && fn_ofs >= this->ofs.
+		 * 
+		 * Remember, 'this' has higher version, any non-hole node
+		 * which is already in the fragtree is newer then the newly
+		 * inserted.
+		 */
+		if (!this->node) {
+			/* 
+			 * 'this' is the hole fragment, so at least the
+			 * beginning of the new fragment is valid.
+			 */
+			
+			/* 
+			 * We are going to insert the new node into the
+			 * fragment tree, so check it.
+			 */
+			if (!checked) {
+				err = check_node(c, f, tn);
+				if (unlikely(err != 0))
+					return err;
+				checked = 1;
+			}
+			
+			if (this->ofs + this->size >= fn_ofs + fn_size) {
+				/* We split the hole on two parts */
+
+				fn->frags += 1;
+				newfrag = new_fragment(fn, fn_ofs, fn_size);
+				if (unlikely(!newfrag))
+					return -ENOMEM;
+
+				err = split_hole(c, root, newfrag, this);
+				if (unlikely(err))
+					return err;
+				goto out_ok;
+			}
+
+			/* 
+			 * The beginning of the new fragment is valid since it
+			 * overlaps the hole node.
+			 */
+
+			ref_flag = REF_NORMAL;
+
+			fn->frags += 1;
+			newfrag = new_fragment(fn, fn_ofs,
+					this->ofs + this->size - fn_ofs);
+			if (unlikely(!newfrag))
+				return -ENOMEM;
+			
+			if (fn_ofs == this->ofs) {
+				/* 
+				 * The new node starts at the same offset as
+				 * the hole and supersieds the hole.
+				 */
+				JFFS2_DBG_FRAGTREE2("add the new fragment instead of hole %#04x-%#04x, refcnt %d\n",
+					fn_ofs, fn_ofs + this->ofs + this->size - fn_ofs, fn->frags);
+
+				rb_replace_node(&this->rb, &newfrag->rb, root);
+				jffs2_free_node_frag(this);
+			} else {
+				/* 
+				 * The hole becomes shorter as its right part
+				 * is supersieded by the new fragment.
+				 */
+				JFFS2_DBG_FRAGTREE2("reduce size of hole %#04x-%#04x to %#04x-%#04x\n",
+					this->ofs, this->ofs + this->size, this->ofs, this->ofs + this->size - newfrag->size);
+				
+				JFFS2_DBG_FRAGTREE2("add new fragment %#04x-%#04x, refcnt %d\n", fn_ofs,
+					fn_ofs + this->ofs + this->size - fn_ofs, fn->frags);
+	
+				this->size -= newfrag->size;
+				jffs2_fragtree_insert(newfrag, this);
+				rb_insert_color(&newfrag->rb, root);
+			}
+			
+			fn_ofs += newfrag->size;
+			fn_size -= newfrag->size;
+			this = rb_entry(rb_next(&newfrag->rb),
+					struct jffs2_node_frag, rb);
+
+			JFFS2_DBG_FRAGTREE2("switch to the next 'this' fragment: %#04x-%#04x %s\n",
+				this->ofs, this->ofs + this->size, this->node ? "(data)" : "(hole)");
+		}
+
+		/* 
+		 * 'This' node is not the hole so it obsoletes the new fragment
+		 * either fully or partially.
+		 */
+		if (this->ofs + this->size >= fn_ofs + fn_size) {
+			/* The new node is obsolete, drop it */
+			if (fn->frags == 0) {
+				JFFS2_DBG_FRAGTREE2("%#04x-%#04x is obsolete, mark it obsolete\n", fn_ofs, fn_ofs + fn_size);
+				ref_flag = REF_OBSOLETE;
+			}
+			goto out_ok;
+		} else {
+			struct jffs2_node_frag *new_this;
+			
+			/* 'This' node obsoletes the beginning of the new node */
+			JFFS2_DBG_FRAGTREE2("the beginning %#04x-%#04x is obsolete\n", fn_ofs, this->ofs + this->size);
+
+			ref_flag = REF_NORMAL;
+			
+			fn_size -= this->ofs + this->size - fn_ofs;
+			fn_ofs = this->ofs + this->size;
+			JFFS2_DBG_FRAGTREE2("now considering %#04x-%#04x\n", fn_ofs, fn_ofs + fn_size);
+			
+			new_this = rb_entry(rb_next(&this->rb), struct jffs2_node_frag, rb);
+			if (!new_this) {
+				/* 
+				 * There is no next fragment. Add the rest of
+				 * the new node as the right-hand child.
+				 */
+				if (!checked) {
+					err = check_node(c, f, tn);
+					if (unlikely(err != 0))
+						return err;
+					checked = 1;
+				}
+				
+				fn->frags += 1;
+				newfrag = new_fragment(fn, fn_ofs, fn_size);
+				if (unlikely(!newfrag))
+					return -ENOMEM;
+
+				JFFS2_DBG_FRAGTREE2("there are no more fragments, insert %#04x-%#04x\n",
+					newfrag->ofs, newfrag->ofs + newfrag->size);
+				rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right);			
+				rb_insert_color(&newfrag->rb, root);
+				goto out_ok;
+			} else {
+				this = new_this;
+				JFFS2_DBG_FRAGTREE2("switch to the next 'this' fragment: %#04x-%#04x %s\n",
+					this->ofs, this->ofs + this->size, this->node ? "(data)" : "(hole)");
+			}
+		}
+	}
+
+out_ok:
+	BUG_ON(fn->size < PAGE_CACHE_SIZE && ref_flag == REF_PRISTINE);
+
+	if (ref_flag == REF_OBSOLETE) {
+		JFFS2_DBG_FRAGTREE2("the node is obsolete now\n");
+		/* jffs2_mark_node_obsolete() will adjust space accounting */
+		jffs2_mark_node_obsolete(c, fn->raw);
+		return 1;
+	}
+
+	JFFS2_DBG_FRAGTREE2("the node is \"%s\" now\n", ref_flag == REF_NORMAL ? "REF_NORMAL" : "REF_PRISTINE");
+
+	/* Space accounting was adjusted at check_node_data() */
+	spin_lock(&c->erase_completion_lock);
+	fn->raw->flash_offset = ref_offset(fn->raw) | ref_flag;
+	spin_unlock(&c->erase_completion_lock);
+
+	return 0;
+}
 
 void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state)
 {