diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 70b6ddfe15a1..6ba5394834be 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -124,6 +124,7 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
 	btrfs_set_header_bytenr(cow, cow->start);
 	btrfs_set_header_generation(cow, trans->transid);
 	btrfs_set_header_owner(cow, new_root_objectid);
+	btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN);
 
 	WARN_ON(btrfs_header_generation(buf) > trans->transid);
 	ret = btrfs_inc_ref(trans, new_root, buf);
@@ -183,6 +184,7 @@ int __btrfs_cow_block(struct btrfs_trans_handle *trans,
 	btrfs_set_header_bytenr(cow, cow->start);
 	btrfs_set_header_generation(cow, trans->transid);
 	btrfs_set_header_owner(cow, root->root_key.objectid);
+	btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN);
 
 	WARN_ON(btrfs_header_generation(buf) > trans->transid);
 	if (btrfs_header_generation(buf) != trans->transid) {
@@ -245,11 +247,14 @@ int btrfs_cow_block(struct btrfs_trans_handle *trans,
 	}
 
 	header_trans = btrfs_header_generation(buf);
-	if (header_trans == trans->transid) {
+	spin_lock(&root->fs_info->hash_lock);
+	if (header_trans == trans->transid &&
+	    !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
 		*cow_ret = buf;
+		spin_unlock(&root->fs_info->hash_lock);
 		return 0;
 	}
-
+	spin_unlock(&root->fs_info->hash_lock);
 	search_start = buf->start & ~((u64)(1024 * 1024 * 1024) - 1);
 	ret = __btrfs_cow_block(trans, root, buf, parent,
 				 parent_slot, cow_ret, search_start, 0);
@@ -1494,6 +1499,7 @@ static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root
 	btrfs_set_header_bytenr(split, split->start);
 	btrfs_set_header_generation(split, trans->transid);
 	btrfs_set_header_owner(split, root->root_key.objectid);
+	btrfs_set_header_flags(split, 0);
 	write_extent_buffer(split, root->fs_info->fsid,
 			    (unsigned long)btrfs_header_fsid(split),
 			    BTRFS_FSID_SIZE);
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index fec96ba7c23b..67d533cf8f47 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -193,6 +193,8 @@ static inline unsigned long btrfs_chunk_item_size(int num_stripes)
 }
 
 #define BTRFS_FSID_SIZE 16
+#define BTRFS_HEADER_FLAG_WRITTEN (1 << 0)
+
 /*
  * every tree block (leaf or node) starts with this header.
  */
@@ -200,10 +202,10 @@ struct btrfs_header {
 	u8 csum[BTRFS_CSUM_SIZE];
 	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
 	__le64 bytenr; /* which block this node is supposed to live in */
+	__le64 flags;
 	__le64 generation;
 	__le64 owner;
 	__le32 nritems;
-	__le16 flags;
 	u8 level;
 } __attribute__ ((__packed__));
 
@@ -229,9 +231,10 @@ struct btrfs_header {
  */
 struct btrfs_super_block {
 	u8 csum[BTRFS_CSUM_SIZE];
-	/* the first 3 fields must match struct btrfs_header */
+	/* the first 4 fields must match struct btrfs_header */
 	u8 fsid[16];    /* FS specific uuid */
 	__le64 bytenr; /* this block number */
+	__le64 flags;
 	__le64 magic;
 	__le64 generation;
 	__le64 root;
@@ -1045,9 +1048,28 @@ BTRFS_SETGET_HEADER_FUNCS(header_generation, struct btrfs_header,
 			  generation, 64);
 BTRFS_SETGET_HEADER_FUNCS(header_owner, struct btrfs_header, owner, 64);
 BTRFS_SETGET_HEADER_FUNCS(header_nritems, struct btrfs_header, nritems, 32);
-BTRFS_SETGET_HEADER_FUNCS(header_flags, struct btrfs_header, flags, 16);
+BTRFS_SETGET_HEADER_FUNCS(header_flags, struct btrfs_header, flags, 64);
 BTRFS_SETGET_HEADER_FUNCS(header_level, struct btrfs_header, level, 8);
 
+static inline int btrfs_header_flag(struct extent_buffer *eb, u64 flag)
+{
+	return (btrfs_header_flags(eb) & flag) == flag;
+}
+
+static inline int btrfs_set_header_flag(struct extent_buffer *eb, u64 flag)
+{
+	u64 flags = btrfs_header_flags(eb);
+	btrfs_set_header_flags(eb, flags | flag);
+	return (flags & flag) == flag;
+}
+
+static inline int btrfs_clear_header_flag(struct extent_buffer *eb, u64 flag)
+{
+	u64 flags = btrfs_header_flags(eb);
+	btrfs_set_header_flags(eb, flags & ~flag);
+	return (flags & flag) == flag;
+}
+
 static inline u8 *btrfs_header_fsid(struct extent_buffer *eb)
 {
 	unsigned long ptr = offsetof(struct btrfs_header, fsid);
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 1c5e097a4df2..709e33d08bb5 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -159,17 +159,19 @@ static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 			from_this_trans = 1;
 
 		/* FIXME, this is not good */
-		if (from_this_trans == 0 &&
-		    memcmp_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE)) {
+		if (memcmp_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE)) {
 			u32 val;
 			u32 found = 0;
 			memcpy(&found, result, BTRFS_CRC32_SIZE);
 
 			read_extent_buffer(buf, &val, 0, BTRFS_CRC32_SIZE);
+			WARN_ON(1);
 			printk("btrfs: %s checksum verify failed on %llu "
-			       "wanted %X found %X from_this_trans %d\n",
+			       "wanted %X found %X from_this_trans %d "
+			       "level %d\n",
 			       root->fs_info->sb->s_id,
-			       buf->start, val, found, from_this_trans);
+			       buf->start, val, found, from_this_trans,
+			       btrfs_header_level(buf));
 			return 1;
 		}
 	} else {
@@ -220,6 +222,9 @@ int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
 		goto err;
 	}
 	found_level = btrfs_header_level(eb);
+	spin_lock(&root->fs_info->hash_lock);
+	btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
+	spin_unlock(&root->fs_info->hash_lock);
 	csum_tree_block(root, eb, 0);
 err:
 	free_extent_buffer(eb);