Btrfs: Add back pointers from the inode to the directory that references it

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 19 insertions, 2 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index cb1b156d954e..035fa1550343 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -53,7 +53,7 @@ extern struct kmem_cache *btrfs_path_cachep;
 #define BTRFS_CSUM_SIZE 32
 /* four bytes for CRC32 */
 #define BTRFS_CRC32_SIZE 4
-#define BTRFS_EMPTY_DIR_SIZE 6
+#define BTRFS_EMPTY_DIR_SIZE 0
 
 #define BTRFS_FT_UNKNOWN        0
 #define BTRFS_FT_REG_FILE       1
@@ -206,6 +206,11 @@ struct btrfs_extent_ref {
         __le64 offset;
 } __attribute__ ((__packed__));
 
+struct btrfs_inode_ref {
+        __le16 name_len;
+        /* name goes here */
+} __attribute__ ((__packed__));
+
 struct btrfs_inode_timespec {
         __le64 sec;
         __le32 nsec;
@@ -379,7 +384,8 @@ struct btrfs_root {
  * the FS
  */
 #define BTRFS_INODE_ITEM_KEY            1
-#define BTRFS_XATTR_ITEM_KEY            2
+#define BTRFS_INODE_REF_KEY             2
+#define BTRFS_XATTR_ITEM_KEY            8
 /* reserve 2-15 close to the inode for later flexibility */
 
 /*
@@ -486,6 +492,9 @@ BTRFS_SETGET_STACK_FUNCS(block_group_used, struct btrfs_block_group_item,
 BTRFS_SETGET_FUNCS(disk_block_group_used, struct btrfs_block_group_item,
                          used, 64);
 
+/* struct btrfs_inode_ref */
+BTRFS_SETGET_FUNCS(inode_ref_name_len, struct btrfs_inode_ref, name_len, 16);
+
 /* struct btrfs_inode_item */
 BTRFS_SETGET_FUNCS(inode_generation, struct btrfs_inode_item, generation, 64);
 BTRFS_SETGET_FUNCS(inode_size, struct btrfs_inode_item, size, 64);
@@ -1043,6 +1052,14 @@ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
 int btrfs_find_highest_inode(struct btrfs_root *fs_root, u64 *objectid);
 
 /* inode-item.c */
+int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
+                           struct btrfs_root *root,
+                           const char *name, int name_len,
+                           u64 inode_objectid, u64 ref_objectid);
+int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
+                           struct btrfs_root *root,
+                           const char *name, int name_len,
+                           u64 inode_objectid, u64 ref_objectid);
 int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans,
                              struct btrfs_root *root,
                              struct btrfs_path *path, u64 objectid);