Btrfs: 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 references to file extent
are recorded explicitly. We can scan these tree leaves very quickly, so the
offset field is not required.

This patch also makes the back reference system check the objectid
when extents are in deleting.

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

1 files changed, 12 insertions, 12 deletions

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 2eab4643dcbc..9caeb377de63 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -254,8 +254,7 @@ int noinline __btrfs_cow_block(struct btrfs_trans_handle *trans,
 
                 ret = btrfs_alloc_reserved_extent(trans, root, parent_start,
                                                   root->root_key.objectid,
-                                                  trans->transid, level, 0,
-                                                  &ins);
+                                                  trans->transid, level, &ins);
                 BUG_ON(ret);
                 cow = btrfs_init_new_buffer(trans, root, prealloc_dest,
                                             buf->len);
@@ -333,7 +332,7 @@ int noinline __btrfs_cow_block(struct btrfs_trans_handle *trans,
                                           buf->len, buf->start,
                                           root->root_key.objectid,
                                           btrfs_header_generation(buf),
-                                          0, 0, 1);
+                                          level, 1);
                 }
                 free_extent_buffer(buf);
                 add_root_to_dirty_list(root);
@@ -347,7 +346,7 @@ int noinline __btrfs_cow_block(struct btrfs_trans_handle *trans,
                 WARN_ON(btrfs_header_generation(parent) != trans->transid);
                 btrfs_free_extent(trans, root, buf->start, buf->len,
                                   parent_start, btrfs_header_owner(parent),
-                                  btrfs_header_generation(parent), 0, 0, 1);
+                                  btrfs_header_generation(parent), level, 1);
         }
         if (unlock_orig)
                 btrfs_tree_unlock(buf);
@@ -927,7 +926,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
                 ret = btrfs_update_extent_ref(trans, root, child->start,
                                               mid->start, child->start,
                                               root->root_key.objectid,
-                                              trans->transid, level - 1, 0);
+                                              trans->transid, level - 1);
                 BUG_ON(ret);
 
                 add_root_to_dirty_list(root);
@@ -940,7 +939,8 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
                 free_extent_buffer(mid);
                 ret = btrfs_free_extent(trans, root, mid->start, mid->len,
                                         mid->start, root->root_key.objectid,
-                                        btrfs_header_generation(mid), 0, 0, 1);
+                                        btrfs_header_generation(mid),
+                                        level, 1);
                 /* once for the root ptr */
                 free_extent_buffer(mid);
                 return ret;
@@ -1006,7 +1006,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
                         wret = btrfs_free_extent(trans, root, bytenr,
                                                  blocksize, parent->start,
                                                  btrfs_header_owner(parent),
-                                                 generation, 0, 0, 1);
+                                                 generation, level, 1);
                         if (wret)
                                 ret = wret;
                 } else {
@@ -1055,7 +1055,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
                 wret = btrfs_free_extent(trans, root, bytenr, blocksize,
                                          parent->start,
                                          btrfs_header_owner(parent),
-                                         root_gen, 0, 0, 1);
+                                         root_gen, level, 1);
                 if (wret)
                         ret = wret;
         } else {
@@ -1691,13 +1691,13 @@ next_level:
                                         blocksize, parent->start,
                                         btrfs_header_owner(parent),
                                         btrfs_header_generation(parent),
-                                        level - 1, 0);
+                                        level - 1);
                 BUG_ON(ret);
                 ret = btrfs_free_extent(trans, root, bytenr,
                                         blocksize, parent->start,
                                         btrfs_header_owner(parent),
                                         btrfs_header_generation(parent),
-                                        level - 1, 0, 1);
+                                        level - 1, 1);
                 BUG_ON(ret);
 
                 if (generation == trans->transid) {
@@ -1973,7 +1973,7 @@ static int noinline insert_new_root(struct btrfs_trans_handle *trans,
         ret = btrfs_update_extent_ref(trans, root, lower->start,
                                       lower->start, c->start,
                                       root->root_key.objectid,
-                                      trans->transid, level - 1, 0);
+                                      trans->transid, level - 1);
         BUG_ON(ret);
 
         /* the super has an extra ref to root->node */
@@ -3213,7 +3213,7 @@ noinline int btrfs_del_leaf(struct btrfs_trans_handle *trans,
                                 btrfs_level_size(root, 0),
                                 path->nodes[1]->start,
                                 btrfs_header_owner(path->nodes[1]),
-                                root_gen, 0, 0, 1);
+                                root_gen, 0, 1);
         return ret;
 }
 /*