diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 69db54e..ab36769 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -525,31 +525,28 @@
  * - Objectid of the subvolume root
  * - Generation number of the tree holding the reference
  * - objectid of the file holding the reference
- * - offset in the file corresponding to the key holding the reference
  * - number of references holding by parent node (alway 1 for tree blocks)
  *
  * Btree leaf may hold multiple references to a file extent. In most cases,
  * these references are from same file and the corresponding offsets inside
- * the file are close together. So inode objectid and offset in file are
- * just hints, they provide hints about where in the btree the references
- * can be found and when we can stop searching.
+ * the file are close together.
  *
  * When a file extent is allocated the fields are filled in:
- *     (root_key.objectid, trans->transid, inode objectid, offset in file, 1)
+ *     (root_key.objectid, trans->transid, inode objectid, 1)
  *
  * When a leaf is cow'd new references are added for every file extent found
  * in the leaf.  It looks similar to the create case, but trans->transid will
  * be different when the block is cow'd.
  *
- *     (root_key.objectid, trans->transid, inode objectid, offset in file,
+ *     (root_key.objectid, trans->transid, inode objectid,
  *      number of references in the leaf)
  *
- * Because inode objectid and offset in file are just hints, they are not
- * used when backrefs are deleted. When a file extent is removed either
- * during snapshot deletion or file truncation, we find the corresponding
- * back back reference and check the following fields.
+ * When a file extent is removed either during snapshot deletion or
+ * file truncation, we find the corresponding back reference and check
+ * the following fields:
  *
- *     (btrfs_header_owner(leaf), btrfs_header_generation(leaf))
+ *     (btrfs_header_owner(leaf), btrfs_header_generation(leaf),
+ *      inode objectid)
  *
  * Btree extents can be referenced by:
  *
@@ -558,21 +555,21 @@
  *
  * When a tree block is created, back references are inserted:
  *
- * (root->root_key.objectid, trans->transid, level, 0, 1)
+ * (root->root_key.objectid, trans->transid, level, 1)
  *
  * When a tree block is cow'd, new back references are added for all the
  * blocks it points to. If the tree block isn't in reference counted root,
  * the old back references are removed. These new back references are of
  * the form (trans->transid will have increased since creation):
  *
- * (root->root_key.objectid, trans->transid, level, 0, 1)
+ * (root->root_key.objectid, trans->transid, level, 1)
  *
  * When a backref is in deleting, the following fields are checked:
  *
  * if backref was for a tree root:
- *     (btrfs_header_owner(itself), btrfs_header_generation(itself))
+ *     (btrfs_header_owner(itself), btrfs_header_generation(itself), level)
  * else
- *     (btrfs_header_owner(parent), btrfs_header_generation(parent))
+ *     (btrfs_header_owner(parent), btrfs_header_generation(parent), level)
  *
  * Back Reference Key composing:
  *
@@ -584,13 +581,15 @@
 
 static int noinline lookup_extent_backref(struct btrfs_trans_handle *trans,
 					  struct btrfs_root *root,
-					  struct btrfs_path *path, u64 bytenr,
-					  u64 parent, u64 ref_root,
-					  u64 ref_generation, int del)
+					  struct btrfs_path *path,
+					  u64 bytenr, u64 parent,
+					  u64 ref_root, u64 ref_generation,
+					  u64 owner_objectid, int del)
 {
 	struct btrfs_key key;
 	struct btrfs_extent_ref *ref;
 	struct extent_buffer *leaf;
+	u64 ref_objectid;
 	int ret;
 
 	key.objectid = bytenr;
@@ -607,8 +606,11 @@
 
 	leaf = path->nodes[0];
 	ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref);
+	ref_objectid = btrfs_ref_objectid(leaf, ref);
 	if (btrfs_ref_root(leaf, ref) != ref_root ||
-	    btrfs_ref_generation(leaf, ref) != ref_generation) {
+	    btrfs_ref_generation(leaf, ref) != ref_generation ||
+	    (ref_objectid != owner_objectid &&
+	     ref_objectid != BTRFS_MULTIPLE_OBJECTIDS)) {
 		ret = -EIO;
 		WARN_ON(1);
 		goto out;
@@ -623,7 +625,7 @@
 					  struct btrfs_path *path,
 					  u64 bytenr, u64 parent,
 					  u64 ref_root, u64 ref_generation,
-					  u64 owner_objectid, u64 owner_offset)
+					  u64 owner_objectid)
 {
 	struct btrfs_key key;
 	struct extent_buffer *leaf;
@@ -643,7 +645,6 @@
 		btrfs_set_ref_root(leaf, ref, ref_root);
 		btrfs_set_ref_generation(leaf, ref, ref_generation);
 		btrfs_set_ref_objectid(leaf, ref, owner_objectid);
-		btrfs_set_ref_offset(leaf, ref, owner_offset);
 		btrfs_set_ref_num_refs(leaf, ref, 1);
 	} else if (ret == -EEXIST) {
 		u64 existing_owner;
@@ -663,14 +664,10 @@
 		btrfs_set_ref_num_refs(leaf, ref, num_refs + 1);
 
 		existing_owner = btrfs_ref_objectid(leaf, ref);
-		if (existing_owner == owner_objectid &&
-		    btrfs_ref_offset(leaf, ref) > owner_offset) {
-			btrfs_set_ref_offset(leaf, ref, owner_offset);
-		} else if (existing_owner != owner_objectid &&
-			   existing_owner != BTRFS_MULTIPLE_OBJECTIDS) {
+		if (existing_owner != owner_objectid &&
+		    existing_owner != BTRFS_MULTIPLE_OBJECTIDS) {
 			btrfs_set_ref_objectid(leaf, ref,
 					BTRFS_MULTIPLE_OBJECTIDS);
-			btrfs_set_ref_offset(leaf, ref, 0);
 		}
 		ret = 0;
 	} else {
@@ -711,7 +708,7 @@
 				     u64 orig_parent, u64 parent,
 				     u64 orig_root, u64 ref_root,
 				     u64 orig_generation, u64 ref_generation,
-				     u64 owner_objectid, u64 owner_offset)
+				     u64 owner_objectid)
 {
 	int ret;
 	struct btrfs_root *extent_root = root->fs_info->extent_root;
@@ -762,7 +759,7 @@
 		return -ENOMEM;
 	ret = lookup_extent_backref(trans, extent_root, path,
 				    bytenr, orig_parent, orig_root,
-				    orig_generation, 1);
+				    orig_generation, owner_objectid, 1);
 	if (ret)
 		goto out;
 	ret = remove_extent_backref(trans, extent_root, path);
@@ -770,7 +767,7 @@
 		goto out;
 	ret = insert_extent_backref(trans, extent_root, path, bytenr,
 				    parent, ref_root, ref_generation,
-				    owner_objectid, owner_offset);
+				    owner_objectid);
 	BUG_ON(ret);
 	finish_current_insert(trans, extent_root);
 	del_pending_extents(trans, extent_root);
@@ -783,7 +780,7 @@
 			    struct btrfs_root *root, u64 bytenr,
 			    u64 orig_parent, u64 parent,
 			    u64 ref_root, u64 ref_generation,
-			    u64 owner_objectid, u64 owner_offset)
+			    u64 owner_objectid)
 {
 	int ret;
 	if (ref_root == BTRFS_TREE_LOG_OBJECTID &&
@@ -793,7 +790,7 @@
 	ret = __btrfs_update_extent_ref(trans, root, bytenr, orig_parent,
 					parent, ref_root, ref_root,
 					ref_generation, ref_generation,
-					owner_objectid, owner_offset);
+					owner_objectid);
 	maybe_unlock_mutex(root);
 	return ret;
 }
@@ -803,7 +800,7 @@
 				  u64 orig_parent, u64 parent,
 				  u64 orig_root, u64 ref_root,
 				  u64 orig_generation, u64 ref_generation,
-				  u64 owner_objectid, u64 owner_offset)
+				  u64 owner_objectid)
 {
 	struct btrfs_path *path;
 	int ret;
@@ -845,7 +842,7 @@
 	ret = insert_extent_backref(trans, root->fs_info->extent_root,
 				    path, bytenr, parent,
 				    ref_root, ref_generation,
-				    owner_objectid, owner_offset);
+				    owner_objectid);
 	BUG_ON(ret);
 	finish_current_insert(trans, root->fs_info->extent_root);
 	del_pending_extents(trans, root->fs_info->extent_root);
@@ -858,7 +855,7 @@
 			 struct btrfs_root *root,
 			 u64 bytenr, u64 num_bytes, u64 parent,
 			 u64 ref_root, u64 ref_generation,
-			 u64 owner_objectid, u64 owner_offset)
+			 u64 owner_objectid)
 {
 	int ret;
 	if (ref_root == BTRFS_TREE_LOG_OBJECTID &&
@@ -867,7 +864,7 @@
 	maybe_lock_mutex(root);
 	ret = __btrfs_inc_extent_ref(trans, root, bytenr, 0, parent,
 				     0, ref_root, 0, ref_generation,
-				     owner_objectid, owner_offset);
+				     owner_objectid);
 	maybe_unlock_mutex(root);
 	return ret;
 }
@@ -1179,7 +1176,7 @@
 	int ret = 0;
 	int faili = 0;
 	int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
-			    u64, u64, u64, u64, u64, u64, u64, u64, u64);
+			    u64, u64, u64, u64, u64, u64, u64, u64);
 
 	ref_root = btrfs_header_owner(buf);
 	ref_generation = btrfs_header_generation(buf);
@@ -1223,7 +1220,7 @@
 					   orig_buf->start, buf->start,
 					   orig_root, ref_root,
 					   orig_generation, ref_generation,
-					   key.objectid, key.offset);
+					   key.objectid);
 			maybe_unlock_mutex(root);
 
 			if (ret) {
@@ -1238,7 +1235,7 @@
 					   orig_buf->start, buf->start,
 					   orig_root, ref_root,
 					   orig_generation, ref_generation,
-					   level - 1, 0);
+					   level - 1);
 			maybe_unlock_mutex(root);
 			if (ret) {
 				faili = i;
@@ -1314,7 +1311,7 @@
 					    orig_buf->start, buf->start,
 					    orig_root, ref_root,
 					    orig_generation, ref_generation,
-					    key.objectid, key.offset);
+					    key.objectid);
 			maybe_unlock_mutex(root);
 			if (ret)
 				goto fail;
@@ -1325,7 +1322,7 @@
 					    orig_buf->start, buf->start,
 					    orig_root, ref_root,
 					    orig_generation, ref_generation,
-					    level - 1, 0);
+					    level - 1);
 			maybe_unlock_mutex(root);
 			if (ret)
 				goto fail;
@@ -1781,13 +1778,14 @@
 						start, extent_op->parent,
 						extent_root->root_key.objectid,
 						extent_op->generation,
-						extent_op->level, 0);
+						extent_op->level);
 			BUG_ON(err);
 		} else if (extent_op->type == PENDING_BACKREF_UPDATE) {
 			err = lookup_extent_backref(trans, extent_root, path,
 						start, extent_op->orig_parent,
 						extent_root->root_key.objectid,
-						extent_op->orig_generation, 0);
+						extent_op->orig_generation,
+						extent_op->level, 0);
 			BUG_ON(err);
 
 			clear_extent_bits(&info->extent_ins, start, end,
@@ -1870,8 +1868,7 @@
 			 struct btrfs_root *root,
 			 u64 bytenr, u64 num_bytes, u64 parent,
 			 u64 root_objectid, u64 ref_generation,
-			 u64 owner_objectid, u64 owner_offset,
-			 int pin, int mark_free)
+			 u64 owner_objectid, int pin, int mark_free)
 {
 	struct btrfs_path *path;
 	struct btrfs_key key;
@@ -1894,8 +1891,9 @@
 		return -ENOMEM;
 
 	path->reada = 1;
-	ret = lookup_extent_backref(trans, extent_root, path, bytenr, parent,
-				    root_objectid, ref_generation, 1);
+	ret = lookup_extent_backref(trans, extent_root, path,
+				    bytenr, parent, root_objectid,
+				    ref_generation, owner_objectid, 1);
 	if (ret == 0) {
 		struct btrfs_key found_key;
 		extent_slot = path->slots[0];
@@ -1926,9 +1924,8 @@
 		btrfs_print_leaf(extent_root, path->nodes[0]);
 		WARN_ON(1);
 		printk("Unable to find ref byte nr %Lu root %Lu "
-		       " gen %Lu owner %Lu offset %Lu\n", bytenr,
-		       root_objectid, ref_generation, owner_objectid,
-		       owner_offset);
+		       "gen %Lu owner %Lu\n", bytenr,
+		       root_objectid, ref_generation, owner_objectid);
 	}
 
 	leaf = path->nodes[0];
@@ -2068,7 +2065,7 @@
 					    extent_op->orig_parent,
 					    extent_root->root_key.objectid,
 					    extent_op->orig_generation,
-					    extent_op->level, 0, 0, mark_free);
+					    extent_op->level, 0, mark_free);
 			kfree(extent_op);
 		} else {
 			kfree(extent_op);
@@ -2107,7 +2104,7 @@
 			       struct btrfs_root *root,
 			       u64 bytenr, u64 num_bytes, u64 parent,
 			       u64 root_objectid, u64 ref_generation,
-			       u64 owner_objectid, u64 owner_offset, int pin)
+			       u64 owner_objectid, int pin)
 {
 	struct btrfs_root *extent_root = root->fs_info->extent_root;
 	int pending_ret;
@@ -2156,8 +2153,8 @@
 		pin = 1;
 
 	ret = __free_extent(trans, root, bytenr, num_bytes, parent,
-			    root_objectid, ref_generation, owner_objectid,
-			    owner_offset, pin, pin == 0);
+			    root_objectid, ref_generation,
+			    owner_objectid, pin, pin == 0);
 
 	finish_current_insert(trans, root->fs_info->extent_root);
 	pending_ret = del_pending_extents(trans, root->fs_info->extent_root);
@@ -2168,14 +2165,14 @@
 		      struct btrfs_root *root,
 		      u64 bytenr, u64 num_bytes, u64 parent,
 		      u64 root_objectid, u64 ref_generation,
-		      u64 owner_objectid, u64 owner_offset, int pin)
+		      u64 owner_objectid, int pin)
 {
 	int ret;
 
 	maybe_lock_mutex(root);
 	ret = __btrfs_free_extent(trans, root, bytenr, num_bytes, parent,
 				  root_objectid, ref_generation,
-				  owner_objectid, owner_offset, pin);
+				  owner_objectid, pin);
 	maybe_unlock_mutex(root);
 	return ret;
 }
@@ -2522,8 +2519,7 @@
 static int __btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans,
 					 struct btrfs_root *root, u64 parent,
 					 u64 root_objectid, u64 ref_generation,
-					 u64 owner, u64 owner_offset,
-					 struct btrfs_key *ins)
+					 u64 owner, struct btrfs_key *ins)
 {
 	int ret;
 	int pending_ret;
@@ -2597,7 +2593,6 @@
 	btrfs_set_ref_root(path->nodes[0], ref, root_objectid);
 	btrfs_set_ref_generation(path->nodes[0], ref, ref_generation);
 	btrfs_set_ref_objectid(path->nodes[0], ref, owner);
-	btrfs_set_ref_offset(path->nodes[0], ref, owner_offset);
 	btrfs_set_ref_num_refs(path->nodes[0], ref, 1);
 
 	btrfs_mark_buffer_dirty(path->nodes[0]);
@@ -2629,17 +2624,15 @@
 int btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans,
 				struct btrfs_root *root, u64 parent,
 				u64 root_objectid, u64 ref_generation,
-				u64 owner, u64 owner_offset,
-				struct btrfs_key *ins)
+				u64 owner, struct btrfs_key *ins)
 {
 	int ret;
 
 	if (root_objectid == BTRFS_TREE_LOG_OBJECTID)
 		return 0;
 	maybe_lock_mutex(root);
-	ret = __btrfs_alloc_reserved_extent(trans, root, parent,
-					    root_objectid, ref_generation,
-					    owner, owner_offset, ins);
+	ret = __btrfs_alloc_reserved_extent(trans, root, parent, root_objectid,
+					    ref_generation, owner, ins);
 	update_reserved_extents(root, ins->objectid, ins->offset, 0);
 	maybe_unlock_mutex(root);
 	return ret;
@@ -2653,8 +2646,7 @@
 int btrfs_alloc_logged_extent(struct btrfs_trans_handle *trans,
 				struct btrfs_root *root, u64 parent,
 				u64 root_objectid, u64 ref_generation,
-				u64 owner, u64 owner_offset,
-				struct btrfs_key *ins)
+				u64 owner, struct btrfs_key *ins)
 {
 	int ret;
 	struct btrfs_block_group_cache *block_group;
@@ -2665,9 +2657,8 @@
 
 	ret = btrfs_remove_free_space(block_group, ins->objectid, ins->offset);
 	BUG_ON(ret);
-	ret = __btrfs_alloc_reserved_extent(trans, root, parent,
-					    root_objectid, ref_generation,
-					    owner, owner_offset, ins);
+	ret = __btrfs_alloc_reserved_extent(trans, root, parent, root_objectid,
+					    ref_generation, owner, ins);
 	maybe_unlock_mutex(root);
 	return ret;
 }
@@ -2683,8 +2674,7 @@
 		       struct btrfs_root *root,
 		       u64 num_bytes, u64 parent, u64 min_alloc_size,
 		       u64 root_objectid, u64 ref_generation,
-		       u64 owner_objectid, u64 owner_offset,
-		       u64 empty_size, u64 hint_byte,
+		       u64 owner_objectid, u64 empty_size, u64 hint_byte,
 		       u64 search_end, struct btrfs_key *ins, u64 data)
 {
 	int ret;
@@ -2698,7 +2688,7 @@
 	if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
 		ret = __btrfs_alloc_reserved_extent(trans, root, parent,
 					root_objectid, ref_generation,
-					owner_objectid, owner_offset, ins);
+					owner_objectid, ins);
 		BUG_ON(ret);
 
 	} else {
@@ -2750,7 +2740,7 @@
 	struct extent_buffer *buf;
 
 	ret = btrfs_alloc_extent(trans, root, blocksize, parent, blocksize,
-				 root_objectid, ref_generation, level, 0,
+				 root_objectid, ref_generation, level,
 				 empty_size, hint, (u64)-1, &ins, 0);
 	if (ret) {
 		BUG_ON(ret > 0);
@@ -2800,7 +2790,7 @@
 		ret = __btrfs_free_extent(trans, root, disk_bytenr,
 				btrfs_file_extent_disk_num_bytes(leaf, fi),
 				leaf->start, leaf_owner, leaf_generation,
-				key.objectid, key.offset, 0);
+				key.objectid, 0);
 		mutex_unlock(&root->fs_info->alloc_mutex);
 		BUG_ON(ret);
 
@@ -2824,7 +2814,7 @@
 		ret = __btrfs_free_extent(trans, root, info->bytenr,
 					  info->num_bytes, ref->bytenr,
 					  ref->owner, ref->generation,
-					  info->objectid, info->offset, 0);
+					  info->objectid, 0);
 		mutex_unlock(&root->fs_info->alloc_mutex);
 
 		atomic_inc(&root->fs_info->throttle_gen);
@@ -2940,7 +2930,8 @@
 			mutex_lock(&root->fs_info->alloc_mutex);
 			ret = __btrfs_free_extent(trans, root, bytenr,
 						blocksize, parent->start,
-						root_owner, root_gen, 0, 0, 1);
+						root_owner, root_gen,
+						*level - 1, 1);
 			BUG_ON(ret);
 			mutex_unlock(&root->fs_info->alloc_mutex);
 
@@ -2970,9 +2961,10 @@
 				*level = 0;
 				break;
 			}
-			if (printk_ratelimit())
+			if (printk_ratelimit()) {
 				printk("leaf ref miss for bytenr %llu\n",
 				       (unsigned long long)bytenr);
+			}
 		}
 		next = btrfs_find_tree_block(root, bytenr, blocksize);
 		if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
@@ -3020,7 +3012,7 @@
 	mutex_lock(&root->fs_info->alloc_mutex);
 	ret = __btrfs_free_extent(trans, root, bytenr, blocksize,
 				  parent->start, root_owner, root_gen,
-				  0, 0, 1);
+				  *level, 1);
 	mutex_unlock(&root->fs_info->alloc_mutex);
 	free_extent_buffer(path->nodes[*level]);
 	path->nodes[*level] = NULL;
@@ -3073,8 +3065,8 @@
 			ret = btrfs_free_extent(trans, root,
 						path->nodes[*level]->start,
 						path->nodes[*level]->len,
-						parent->start,
-						root_owner, root_gen, 0, 0, 1);
+						parent->start, root_owner,
+						root_gen, *level, 1);
 			BUG_ON(ret);
 			free_extent_buffer(path->nodes[*level]);
 			path->nodes[*level] = NULL;
@@ -3308,7 +3300,6 @@
 	u64 root_objectid;
 	u64 root_generation;
 	u64 owner_objectid;
-	u64 owner_offset;
 	u32 num_refs;
 	int lowest_level;
 	int current_level;
@@ -3480,7 +3471,6 @@
 
 		if (ref_path->lowest_level == level) {
 			ref_path->owner_objectid = ref_objectid;
-			ref_path->owner_offset = btrfs_ref_offset(leaf, ref);
 			ref_path->num_refs = btrfs_ref_num_refs(leaf, ref);
 		}
 
@@ -3686,16 +3676,20 @@
 	u64 ext_offset;
 	u64 first_pos;
 	u32 nritems;
+	int nr_scaned = 0;
 	int extent_locked = 0;
 	int ret;
 
-	first_pos = ref_path->owner_offset;
+	memcpy(&key, leaf_key, sizeof(key));
+	first_pos = INT_LIMIT(loff_t) - extent_key->offset;
 	if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
-		key.objectid = ref_path->owner_objectid;
-		key.offset = ref_path->owner_offset;
-		key.type = BTRFS_EXTENT_DATA_KEY;
-	} else {
-		memcpy(&key, leaf_key, sizeof(key));
+		if (key.objectid < ref_path->owner_objectid ||
+		    (key.objectid == ref_path->owner_objectid &&
+		     key.type < BTRFS_EXTENT_DATA_KEY)) {
+			key.objectid = ref_path->owner_objectid;
+			key.type = BTRFS_EXTENT_DATA_KEY;
+			key.offset = 0;
+		}
 	}
 
 	while (1) {
@@ -3718,8 +3712,7 @@
 		}
 
 		if (path->slots[0] >= nritems) {
-			if (ref_path->owner_objectid ==
-			    BTRFS_MULTIPLE_OBJECTIDS)
+			if (++nr_scaned > 2)
 				break;
 
 			BUG_ON(extent_locked);
@@ -3858,7 +3851,7 @@
 						leaf->start,
 						root->root_key.objectid,
 						trans->transid,
-						key.objectid, key.offset);
+						key.objectid);
 			BUG_ON(ret);
 
 			ret = btrfs_free_extent(trans, root,
@@ -3867,7 +3860,7 @@
 						leaf->start,
 						btrfs_header_owner(leaf),
 						btrfs_header_generation(leaf),
-						key.objectid, key.offset, 0);
+						key.objectid, 0);
 			BUG_ON(ret);
 
 			btrfs_release_path(root, path);
@@ -3925,8 +3918,7 @@
 						new_extents[i].disk_num_bytes,
 						leaf->start,
 						root->root_key.objectid,
-						trans->transid,
-						key.objectid, key.offset);
+						trans->transid, key.objectid);
 				BUG_ON(ret);
 				btrfs_release_path(root, path);
 
@@ -4182,14 +4174,13 @@
 					new_extent->disk_num_bytes,
 					leaf->start,
 					root->root_key.objectid,
-					trans->transid,
-					key.objectid, key.offset);
+					trans->transid, key.objectid);
 		BUG_ON(ret);
 		ret = btrfs_free_extent(trans, root,
 					bytenr, num_bytes, leaf->start,
 					btrfs_header_owner(leaf),
 					btrfs_header_generation(leaf),
-					key.objectid, key.offset, 0);
+					key.objectid, 0);
 		BUG_ON(ret);
 		cond_resched();
 	}