示例#1
0
/*
 * given a pointer into a directory item, delete it.  This
 * handles items that have more than one entry in them.
 */
int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans,
			      struct btrfs_root *root,
			      struct btrfs_path *path,
			      struct btrfs_dir_item *di)
{

	struct extent_buffer *leaf;
	u32 sub_item_len;
	u32 item_len;
	int ret = 0;

	leaf = path->nodes[0];
	sub_item_len = sizeof(*di) + btrfs_dir_name_len(leaf, di) +
		btrfs_dir_data_len(leaf, di);
	item_len = btrfs_item_size_nr(leaf, path->slots[0]);
	if (sub_item_len == item_len) {
		ret = btrfs_del_item(trans, root, path);
	} else {
		/* MARKER */
		unsigned long ptr = (unsigned long)di;
		unsigned long start;

		start = btrfs_item_ptr_offset(leaf, path->slots[0]);
		memmove_extent_buffer(leaf, ptr, ptr + sub_item_len,
			item_len - (ptr + sub_item_len - start));
		btrfs_truncate_item(trans, root, path,
				    item_len - sub_item_len, 1);
	}
	return ret;
}
示例#2
0
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 *index)
{
	struct btrfs_path *path;
	struct btrfs_key key;
	struct btrfs_inode_ref *ref;
	struct extent_buffer *leaf;
	unsigned long ptr;
	unsigned long item_start;
	u32 item_size;
	u32 sub_item_len;
	int ret;
	int del_len = name_len + sizeof(*ref);

	key.objectid = inode_objectid;
	key.offset = ref_objectid;
	btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);

	path = btrfs_alloc_path();
	if (!path)
		return -ENOMEM;

	path->leave_spinning = 1;

	ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
	if (ret > 0) {
		ret = -ENOENT;
		goto out;
	} else if (ret < 0) {
		goto out;
	}
	if (!find_name_in_backref(path, name, name_len, &ref)) {
		ret = -ENOENT;
		goto out;
	}
	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;
	}
	ptr = (unsigned long)ref;
	sub_item_len = name_len + sizeof(*ref);
	item_start = btrfs_item_ptr_offset(leaf, path->slots[0]);
	memmove_extent_buffer(leaf, ptr, ptr + sub_item_len,
			      item_size - (ptr + sub_item_len - item_start));
	btrfs_truncate_item(trans, root, path,
				  item_size - sub_item_len, 1);
out:
	btrfs_free_path(path);
	return ret;
}
示例#3
0
文件: uuid-tree.c 项目: avagin/linux
int btrfs_uuid_tree_remove(struct btrfs_trans_handle *trans, u8 *uuid, u8 type,
			u64 subid)
{
	struct btrfs_fs_info *fs_info = trans->fs_info;
	struct btrfs_root *uuid_root = fs_info->uuid_root;
	int ret;
	struct btrfs_path *path = NULL;
	struct btrfs_key key;
	struct extent_buffer *eb;
	int slot;
	unsigned long offset;
	u32 item_size;
	unsigned long move_dst;
	unsigned long move_src;
	unsigned long move_len;

	if (WARN_ON_ONCE(!uuid_root)) {
		ret = -EINVAL;
		goto out;
	}

	btrfs_uuid_to_key(uuid, type, &key);

	path = btrfs_alloc_path();
	if (!path) {
		ret = -ENOMEM;
		goto out;
	}

	ret = btrfs_search_slot(trans, uuid_root, &key, path, -1, 1);
	if (ret < 0) {
		btrfs_warn(fs_info, "error %d while searching for uuid item!",
			   ret);
		goto out;
	}
	if (ret > 0) {
		ret = -ENOENT;
		goto out;
	}

	eb = path->nodes[0];
	slot = path->slots[0];
	offset = btrfs_item_ptr_offset(eb, slot);
	item_size = btrfs_item_size_nr(eb, slot);
	if (!IS_ALIGNED(item_size, sizeof(u64))) {
		btrfs_warn(fs_info, "uuid item with illegal size %lu!",
			   (unsigned long)item_size);
		ret = -ENOENT;
		goto out;
	}
	while (item_size) {
		__le64 read_subid;

		read_extent_buffer(eb, &read_subid, offset, sizeof(read_subid));
		if (le64_to_cpu(read_subid) == subid)
			break;
		offset += sizeof(read_subid);
		item_size -= sizeof(read_subid);
	}

	if (!item_size) {
		ret = -ENOENT;
		goto out;
	}

	item_size = btrfs_item_size_nr(eb, slot);
	if (item_size == sizeof(subid)) {
		ret = btrfs_del_item(trans, uuid_root, path);
		goto out;
	}

	move_dst = offset;
	move_src = offset + sizeof(subid);
	move_len = item_size - (move_src - btrfs_item_ptr_offset(eb, slot));
	memmove_extent_buffer(eb, move_dst, move_src, move_len);
	btrfs_truncate_item(path, item_size - sizeof(subid), 1);

out:
	btrfs_free_path(path);
	return ret;
}