Index: linux-2.6.18.i386/fs/ext4/ext4_jbd2.h
===================================================================
--- linux-2.6.18.i386.orig/fs/ext4/ext4_jbd2.h
+++ linux-2.6.18.i386/fs/ext4/ext4_jbd2.h
@@ -35,6 +35,9 @@
 	(EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)	\
 		|| test_opt(sb, EXTENTS) ? 27U : 8U)
 
+/* Indicate that EXT4_SINGLEDATA_TRANS_BLOCKS takes the sb as argument */
+#define EXT4_SINGLEDATA_TRANS_BLOCKS_HAS_SB
+
 /* Extended attribute operations touch at most two data buffers,
  * two bitmap buffers, and two group summaries, in addition to the inode
  * and the superblock, which are already accounted for. */
Index: linux-2.6.18.i386/fs/ext4/extents.c
===================================================================
--- linux-2.6.18.i386.orig/fs/ext4/extents.c
+++ linux-2.6.18.i386/fs/ext4/extents.c
@@ -50,7 +50,7 @@
  * ext_pblock:
  * combine low and high parts of physical block number into ext4_fsblk_t
  */
-static ext4_fsblk_t ext_pblock(struct ext4_extent *ex)
+ext4_fsblk_t ext_pblock(struct ext4_extent *ex)
 {
 	ext4_fsblk_t block;
 
@@ -60,6 +60,17 @@ static ext4_fsblk_t ext_pblock(struct ex
 }
 
 /*
+ * ext4_ext_store_pblock:
+ * stores a large physical block number into an extent struct,
+ * breaking it into parts
+ */
+void ext4_ext_store_pblock(struct ext4_extent *ex, ext4_fsblk_t pb)
+{
+	ex->ee_start_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff));
+	ex->ee_start_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
+}
+
+/*
  * idx_pblock:
  * combine low and high parts of a leaf physical block number into ext4_fsblk_t
  */
@@ -73,17 +84,6 @@ ext4_fsblk_t idx_pblock(struct ext4_exte
 }
 
 /*
- * ext4_ext_store_pblock:
- * stores a large physical block number into an extent struct,
- * breaking it into parts
- */
-void ext4_ext_store_pblock(struct ext4_extent *ex, ext4_fsblk_t pb)
-{
-	ex->ee_start_lo = cpu_to_le32((unsigned long) (pb & 0xffffffff));
-	ex->ee_start_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
-}
-
-/*
  * ext4_idx_store_pblock:
  * stores a large physical block number into an index struct,
  * breaking it into parts
@@ -1826,6 +1826,56 @@ static int ext4_ext_rm_idx(handle_t *han
 }
 
 /*
+ * This routine returns max. credits extent tree can consume.
+ * It should be OK for low-performance paths like ->writepage()
+ * To allow many writing process to fit a single transaction,
+ * caller should calculate credits under truncate_mutex and
+ * pass actual path.
+ */
+int ext4_ext_calc_credits_for_insert(struct inode *inode,
+				    struct ext4_ext_path *path)
+{
+	int depth, needed;
+
+	if (path) {
+		/* probably there is space in leaf? */
+		depth = ext_depth(inode);
+		if (le16_to_cpu(path[depth].p_hdr->eh_entries)
+				< le16_to_cpu(path[depth].p_hdr->eh_max))
+			return 1;
+	}
+
+	/*
+	 * given 32bit logical block (4294967296 blocks), max. tree
+	 * can be 4 levels in depth -- 4 * 340^4 == 53453440000.
+	 * let's also add one more level for imbalance.
+	 */
+	depth = 5;
+
+	/* allocation of new data block(s) */
+	needed = 2;
+
+	/*
+	 * tree can be full, so it'd need to grow in depth:
+	 * we need one credit to modify old root, credits for
+	 * new root will be added in split accounting
+	 */
+	needed += 1;
+
+	/*
+	 * Index split can happen, we'd need:
+	 *    allocate intermediate indexes (bitmap + group)
+	 *  + change two blocks at each level, but root (already included)
+	 */
+	needed += (depth * 2) + (depth * 2);
+
+	/* any allocation modifies superblock */
+	needed += 1;
+
+	return needed;
+}
+
+/*
  * ext4_ext_calc_credits_for_single_extent:
  * This routine returns max. credits that needed to insert an extent
  * to the extent tree.
@@ -3157,3 +3207,14 @@ int ext4_fiemap(struct inode *inode, str
 
 	return error;
 }
+
+EXPORT_SYMBOL(ext4_ext_store_pblock);
+EXPORT_SYMBOL(ext4_ext_search_right);
+EXPORT_SYMBOL(ext4_ext_search_left);
+EXPORT_SYMBOL(ext_pblock);
+EXPORT_SYMBOL(ext4_ext_insert_extent);
+EXPORT_SYMBOL(ext4_mb_new_blocks);
+EXPORT_SYMBOL(ext4_ext_walk_space);
+EXPORT_SYMBOL(ext4_ext_calc_credits_for_insert);
+EXPORT_SYMBOL(ext4_mark_inode_dirty);
+
Index: linux-2.6.18.i386/fs/ext4/ext4_extents.h
===================================================================
--- linux-2.6.18.i386.orig/fs/ext4/ext4_extents.h
+++ linux-2.6.18.i386/fs/ext4/ext4_extents.h
@@ -59,6 +59,11 @@
  */
 #define EXT_STATS_
 
+/*
+ * define EXT4_ALLOC_NEEDED to 0 since block bitmap, group desc. and sb
+ * are now accounted in ext4_ext_calc_credits_for_insert()
+ */
+#define EXT4_ALLOC_NEEDED 0
 
 /*
  * ext4_inode has i_block array (60 bytes total).
@@ -124,6 +129,7 @@ struct ext4_ext_path {
 #define EXT4_EXT_CACHE_GAP	1
 #define EXT4_EXT_CACHE_EXTENT	2
 
+#define EXT4_EXT_HAS_NO_TREE  /* ext4_extents_tree struct is not used*/
 
 #define EXT_MAX_BLOCK	0xffffffff
 
@@ -228,9 +234,13 @@ static inline int ext4_ext_get_actual_le
 		(le16_to_cpu(ext->ee_len) - EXT_INIT_MAX_LEN));
 }
 
+extern ext4_fsblk_t ext_pblock(struct ext4_extent *ex);
+extern void ext4_ext_store_pblock(struct ext4_extent *ex, ext4_fsblk_t pb);
 extern ext4_fsblk_t idx_pblock(struct ext4_extent_idx *);
 extern void ext4_ext_store_pblock(struct ext4_extent *, ext4_fsblk_t);
 extern int ext4_extent_tree_init(handle_t *, struct inode *);
+extern int ext4_ext_calc_credits_for_insert(struct inode *,
+					    struct ext4_ext_path *);
 extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
 						   int num,
 						   struct ext4_ext_path *path);
Index: linux-2.6.18.i386/fs/ext4/mballoc.c
===================================================================
--- linux-2.6.18.i386.orig/fs/ext4/mballoc.c
+++ linux-2.6.18.i386/fs/ext4/mballoc.c
@@ -4965,3 +4965,7 @@ error_return:
 		kmem_cache_free(ext4_ac_cachep, ac);
 	return;
 }
+
+EXPORT_SYMBOL(ext4_free_blocks);
+EXPORT_SYMBOL(ext4_mb_discard_inode_preallocations);
+
Index: linux-2.6.18.i386/fs/ext4/super.c
===================================================================
--- linux-2.6.18.i386.orig/fs/ext4/super.c
+++ linux-2.6.18.i386/fs/ext4/super.c
@@ -91,6 +91,7 @@ ext4_fsblk_t ext4_inode_bitmap(struct su
 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 		(ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 }
+EXPORT_SYMBOL(ext4_inode_bitmap);
 
 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 			      struct ext4_group_desc *bg)
@@ -513,7 +514,8 @@ static void ext4_put_super(struct super_
 	struct ext4_super_block *es = sbi->s_es;
 	int i;
 
-	ext4_mb_release(sb);
+	if (test_opt(sb, MBALLOC))
+		ext4_mb_release(sb);
 	ext4_ext_release(sb);
 	ext4_xattr_put_super(sb);
 	jbd2_journal_destroy(sbi->s_journal);
@@ -2373,16 +2375,6 @@ static int ext4_fill_super(struct super_
 		       "running e2fsck is recommended\n");
 
 	/*
-	 * Since ext4 is still considered development code, we require
-	 * that the TEST_FILESYS flag in s->flags be set.
-	 */
-	if (!(le32_to_cpu(es->s_flags) & EXT2_FLAGS_TEST_FILESYS)) {
-		printk(KERN_WARNING "EXT4-fs: %s: not marked "
-		       "OK to use with test code.\n", sb->s_id);
-		goto failed_mount;
-	}
-
-	/*
 	 * Check feature flags regardless of the revision level, since we
 	 * previously didn't change the revision level when setting the flags,
 	 * so there is a chance incompat flags are set on a rev 0 filesystem.
@@ -3835,9 +3827,9 @@ static int ext4_get_sb(struct file_syste
 	return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super, mnt);
 }
 
-static struct file_system_type ext4dev_fs_type = {
+static struct file_system_type ext4_fs_type = {
 	.owner		= THIS_MODULE,
-	.name		= "ext4dev",
+	.name		= "ext4",
 	.get_sb		= ext4_get_sb,
 	.kill_sb	= kill_block_super,
 #ifdef HAVE_FALLOCATE
@@ -3867,7 +3859,7 @@ static int __init init_ext4_fs(void)
 	err = init_inodecache();
 	if (err)
 		goto out1;
-	err = register_filesystem(&ext4dev_fs_type);
+	err = register_filesystem(&ext4_fs_type);
 	if (err)
 		goto out;
 	return 0;
@@ -3884,7 +3876,7 @@ out3:
 
 static void __exit exit_ext4_fs(void)
 {
-	unregister_filesystem(&ext4dev_fs_type);
+	unregister_filesystem(&ext4_fs_type);
 	destroy_inodecache();
 	exit_ext4_xattr();
 	exit_ext4_mballoc();
Index: linux-2.6.18.i386/fs/ext4/ext4_jbd2.c
===================================================================
--- linux-2.6.18.i386.orig/fs/ext4/ext4_jbd2.c
+++ linux-2.6.18.i386/fs/ext4/ext4_jbd2.c
@@ -21,6 +21,7 @@ int __ext4_journal_get_write_access(cons
 		ext4_journal_abort_handle(where, __func__, bh, handle, err);
 	return err;
 }
+EXPORT_SYMBOL(__ext4_journal_get_write_access);
 
 int __ext4_journal_forget(const char *where, handle_t *handle,
 				struct buffer_head *bh)
@@ -57,3 +58,4 @@ int __ext4_journal_dirty_metadata(const 
 		ext4_journal_abort_handle(where, __func__, bh, handle, err);
 	return err;
 }
+EXPORT_SYMBOL(__ext4_journal_dirty_metadata);