Btrfs: Implement new dir index format

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

fs/btrfs/btrfs_inode.h

@@ -43,6 +43,21 @@ struct btrfs_inode {
 	u64 delalloc_bytes;
 	u64 disk_i_size;
 	u32 flags;
+
+	/*
+	 * if this is a directory then index_cnt is the counter for the index
+	 * number for new files that are created
+	 */
+	u64 index_cnt;
+
+	/*
+	 * index holds the directory index for this inode on creation, so
+	 * add_link can do what its supposed to.  This isn't populated when the
+	 * inode is read because there isn't really a reason to know this unless
+	 * we are creating the directory index or deleting it, and deletion
+	 * reads the index off of the inode reference at unlink time.
+	 */
+	u64 index;
 };
 
 static inline struct btrfs_inode *BTRFS_I(struct inode *inode)

fs/btrfs/ctree.h

@@ -372,6 +372,7 @@ struct btrfs_dev_extent {
 } __attribute__ ((__packed__));
 
 struct btrfs_inode_ref {
+	__le64 index;
 	__le16 name_len;
 	/* name goes here */
 } __attribute__ ((__packed__));
@@ -902,6 +903,7 @@ BTRFS_SETGET_STACK_FUNCS(block_group_flags,
 
 /* struct btrfs_inode_ref */
 BTRFS_SETGET_FUNCS(inode_ref_name_len, struct btrfs_inode_ref, name_len, 16);
+BTRFS_SETGET_FUNCS(inode_ref_index, struct btrfs_inode_ref, index, 64);
 
 /* struct btrfs_inode_item */
 BTRFS_SETGET_FUNCS(inode_generation, struct btrfs_inode_item, generation, 64);
@@ -1528,7 +1530,7 @@ int btrfs_find_dead_roots(struct btrfs_root *root, u64 objectid,
 /* dir-item.c */
 int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
 			  *root, const char *name, int name_len, u64 dir,
-			  struct btrfs_key *location, u8 type);
+			  struct btrfs_key *location, u8 type, u64 index);
 struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
 					     struct btrfs_root *root,
 					     struct btrfs_path *path, u64 dir,
@@ -1566,11 +1568,11 @@ int btrfs_find_highest_inode(struct btrfs_root *fs_root, u64 *objectid);
 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);
+			   u64 inode_objectid, u64 ref_objectid, u64 index);
 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);
+			   u64 inode_objectid, u64 ref_objectid, u64 *index);
 int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans,
 			     struct btrfs_root *root,
 			     struct btrfs_path *path, u64 objectid);

fs/btrfs/dir-item.c

@@ -110,7 +110,7 @@ int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans,
 
 int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
 			  *root, const char *name, int name_len, u64 dir,
-			  struct btrfs_key *location, u8 type)
+			  struct btrfs_key *location, u8 type, u64 index)
 {
 	int ret = 0;
 	int ret2 = 0;
@@ -156,7 +156,7 @@ int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
 	btrfs_release_path(root, path);
 
 	btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
-	key.offset = location->objectid;
+	key.offset = index;
 	dir_item = insert_with_overflow(trans, root, path, &key, data_size,
 					name, name_len);
 	if (IS_ERR(dir_item)) {

fs/btrfs/inode-item.c

@@ -52,7 +52,7 @@ int find_name_in_backref(struct btrfs_path *path, const char * name,
 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)
+			   u64 inode_objectid, u64 ref_objectid, u64 *index)
 {
 	struct btrfs_path *path;
 	struct btrfs_key key;
@@ -86,6 +86,10 @@ int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
 	}
 	leaf = path->nodes[0];
 	item_size = btrfs_item_size_nr(leaf, path->slots[0]);
+
+	if (index)
+		*index = btrfs_inode_ref_index(leaf, ref);
+
 	if (del_len == item_size) {
 		ret = btrfs_del_item(trans, root, path);
 		goto out;
@@ -106,7 +110,7 @@ int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
 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)
+			   u64 inode_objectid, u64 ref_objectid, u64 index)
 {
 	struct btrfs_path *path;
 	struct btrfs_key key;
@@ -138,6 +142,7 @@ int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
 				     struct btrfs_inode_ref);
 		ref = (struct btrfs_inode_ref *)((unsigned long)ref + old_size);
 		btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
+		btrfs_set_inode_ref_index(path->nodes[0], ref, index);
 		ptr = (unsigned long)(ref + 1);
 		ret = 0;
 	} else if (ret < 0) {
@@ -146,6 +151,7 @@ int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
 		ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
 				     struct btrfs_inode_ref);
 		btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
+		btrfs_set_inode_ref_index(path->nodes[0], ref, index);
 		ptr = (unsigned long)(ref + 1);
 	}
 	write_extent_buffer(path->nodes[0], name, ptr, name_len);