Remove offset field from struct btrfs_extent_ref

The offset field in struct btrfs_extent_ref records the position
inside file that file extent is referenced by. In the new back
reference system, tree leaves holding reference to file extent
are recorded explicitly. We can quickly scan these tree leaves, so the
offset field is not required.

This patch also makes the back reference system check the objectid
when extents are being deleted

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>

1 files changed, 4 insertions, 18 deletions

diff --git a/ctree.h b/ctree.h
index fe5f2bfb..90bd9407 100644
--- a/ctree.h
+++ b/ctree.h
@@ -351,7 +351,6 @@ struct btrfs_extent_ref {
 	__le64 root;
 	__le64 generation;
 	__le64 objectid;
-	__le64 offset;
 	__le32 num_refs;
 } __attribute__ ((__packed__));
 
@@ -921,7 +920,6 @@ static inline u8 *btrfs_dev_extent_chunk_tree_uuid(struct btrfs_dev_extent *dev)
 BTRFS_SETGET_FUNCS(ref_root, struct btrfs_extent_ref, root, 64);
 BTRFS_SETGET_FUNCS(ref_generation, struct btrfs_extent_ref, generation, 64);
 BTRFS_SETGET_FUNCS(ref_objectid, struct btrfs_extent_ref, objectid, 64);
-BTRFS_SETGET_FUNCS(ref_offset, struct btrfs_extent_ref, offset, 64);
 BTRFS_SETGET_FUNCS(ref_num_refs, struct btrfs_extent_ref, num_refs, 32);
 
 BTRFS_SETGET_STACK_FUNCS(stack_ref_root, struct btrfs_extent_ref, root, 64);
@@ -929,8 +927,6 @@ BTRFS_SETGET_STACK_FUNCS(stack_ref_generation, struct btrfs_extent_ref,
 			 generation, 64);
 BTRFS_SETGET_STACK_FUNCS(stack_ref_objectid, struct btrfs_extent_ref,
 			 objectid, 64);
-BTRFS_SETGET_STACK_FUNCS(stack_ref_offset, struct btrfs_extent_ref,
-			 offset, 64);
 BTRFS_SETGET_STACK_FUNCS(stack_ref_num_refs, struct btrfs_extent_ref,
 			 num_refs, 32);
 
@@ -1323,21 +1319,11 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
 					     int level,
 					     u64 hint,
 					     u64 empty_size);
-int btrfs_grow_extent_tree(struct btrfs_trans_handle *trans,
-			   struct btrfs_root *root, u64 new_size);
-int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 new_size);
-int btrfs_insert_extent_backref(struct btrfs_trans_handle *trans,
-				 struct btrfs_root *root,
-				 struct btrfs_path *path,
-				 u64 bytenr, u64 parent,
-				 u64 root_objectid, u64 ref_generation,
-				 u64 owner, u64 owner_offset);
 int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
 		       struct btrfs_root *root,
 		       u64 num_bytes, u64 parent,
 		       u64 root_objectid, u64 ref_generation,
-		       u64 owner, u64 owner_offset,
-		       u64 empty_size, u64 hint_byte,
+		       u64 owner, u64 empty_size, u64 hint_byte,
 		       u64 search_end, struct btrfs_key *ins, int data);
 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		  struct extent_buffer *orig_buf, struct extent_buffer *buf,
@@ -1348,7 +1334,7 @@ int btrfs_update_ref(struct btrfs_trans_handle *trans,
 int btrfs_free_extent(struct btrfs_trans_handle *trans, 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 btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
 			       struct btrfs_root *root,
 			       struct extent_io_tree *unpin);
@@ -1356,12 +1342,12 @@ int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
 				struct btrfs_root *root,
 				u64 bytenr, u64 num_bytes, u64 parent,
 				u64 root_objectid, u64 ref_generation,
-				u64 owner, u64 owner_offset);
+				u64 owner_objectid);
 int btrfs_update_extent_ref(struct btrfs_trans_handle *trans,
 			    struct btrfs_root *root, u64 bytenr,
 			    u64 orig_parent, u64 parent,
 			    u64 root_objectid, u64 ref_generation,
-			    u64 owner_objectid, u64 owner_offset);
+			    u64 owner_objectid);
 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
 				    struct btrfs_root *root);
 int btrfs_free_block_groups(struct btrfs_fs_info *info);