1 files changed, 13 insertions, 469 deletions

diff --git a/fs/jffs2/nodelist.c b/fs/jffs2/nodelist.c
index 5a6b4d64206..4bf86088b3a 100644
--- a/fs/jffs2/nodelist.c
+++ b/fs/jffs2/nodelist.c
@@ -1,14 +1,12 @@
 /*
  * JFFS2 -- Journalling Flash File System, Version 2.
  *
- * Copyright (C) 2001-2003 Red Hat, Inc.
+ * Copyright © 2001-2007 Red Hat, Inc.
  *
  * Created by David Woodhouse <dwmw2@infradead.org>
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: nodelist.c,v 1.115 2005/11/07 11:14:40 gleixner Exp $
- *
  */
 
 #include <linux/kernel.h>
@@ -54,7 +52,7 @@ void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new
 	*prev = new;
 }
 
-void jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint32_t size)
+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);
 
@@ -76,18 +74,24 @@ void jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint
 	}
 
 	if (size == 0)
-		return;
+		return 0;
 
-	/*
-	 * If the last fragment starts at the RAM page boundary, it is
-	 * REF_PRISTINE irrespective of its size.
-	 */
 	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.\n",
 			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,
@@ -397,466 +401,6 @@ int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_in
 	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, len;
-	size_t retlen;
-
-	BUG_ON(tn->csize == 0);
-
-	if (!jffs2_is_writebuffered(c))
-		goto adj_acc;
-
-	/* Calculate how many bytes were already checked */
-	ofs = ref_offset(ref) + sizeof(struct jffs2_raw_inode);
-	len = ofs % c->wbuf_pagesize;
-	if (likely(len))
-		len = c->wbuf_pagesize - len;
-
-	if (len >= tn->csize) {
-		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;
-
-	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: %zu 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: %zd 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("wrong 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 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;
-
-	dbg_fragtree2("check node %#04x-%#04x, 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)) {
-		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)
-{
-	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.
-			 */
-
-			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.
-			 */
-			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;
-		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) {
-			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;
-
-	dbg_fragtree("insert fragment %#04x-%#04x, ver %u\n", fn_ofs, fn_ofs + fn_size, tn->version);
-
-	/* Skip all the nodes which are completed before this one starts */
-	this = jffs2_lookup_node_frag(root, fn_ofs);
-	if (this)
-		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.
-				 */
-				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.
-				 */
-				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);
-
-				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);
-
-			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) {
-				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 */
-			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;
-			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;
-
-				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;
-				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) {
-		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;
-	}
-
-	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)
 {
 	spin_lock(&c->inocache_lock);