On 14.02.20 г. 10:13 ч., Qu Wenruo wrote:
> This function will go next inline/keyed backref for
> btrfs_backref_iterator infrastructure.
>
> Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
> ---
> fs/btrfs/backref.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 48 insertions(+)
>
> diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
> index 73c4829609c9..c5f87439f31c 100644
> --- a/fs/btrfs/backref.c
> +++ b/fs/btrfs/backref.c
> @@ -2310,3 +2310,51 @@ int btrfs_backref_iterator_start(struct btrfs_backref_iterator *iterator,
> btrfs_release_path(path);
> return ret;
> }
> +
> +int btrfs_backref_iterator_next(struct btrfs_backref_iterator *iterator)
> +{
make it a bool function.
> + struct extent_buffer *eb = btrfs_backref_get_eb(iterator);
> + struct btrfs_path *path = iterator->path;
> + struct btrfs_extent_inline_ref *iref;
> + int ret;
> + u32 size;
> +
> + if (iterator->cur_key.type == BTRFS_EXTENT_ITEM_KEY ||
> + iterator->cur_key.type == BTRFS_METADATA_ITEM_KEY) {
> + /* We're still inside the inline refs */
> + if (btrfs_backref_has_tree_block_info(iterator)) {
> + /* First tree block info */
> + size = sizeof(struct btrfs_tree_block_info);
> + } else {
> + /* Use inline ref type to determine the size */
> + int type;
> +
> + iref = (struct btrfs_extent_inline_ref *)
> + (iterator->cur_ptr);
> + type = btrfs_extent_inline_ref_type(eb, iref);
> +
> + size = btrfs_extent_inline_ref_size(type);
> + }
> + iterator->cur_ptr += size;
> + if (iterator->cur_ptr < iterator->end_ptr)
> + return 0;
> +
> + /* All inline items iterated, fall through */
> + }
> + /* We're at keyed items, there is no inline item, just go next item */
> + ret = btrfs_next_item(iterator->fs_info->extent_root, iterator->path);
> + if (ret > 0 || ret < 0)
> + return ret;
> +
> + btrfs_item_key_to_cpu(path->nodes[0], &iterator->cur_key,
> + path->slots[0]);
> + if (iterator->cur_key.objectid != iterator->bytenr ||
> + (iterator->cur_key.type != BTRFS_TREE_BLOCK_REF_KEY &&
> + iterator->cur_key.type != BTRFS_SHARED_BLOCK_REF_KEY))
> + return 1;
> + iterator->item_ptr = btrfs_item_ptr_offset(path->nodes[0],
> + path->slots[0]);
> + iterator->cur_ptr = iterator->item_ptr;
> + iterator->end_ptr = btrfs_item_end_nr(path->nodes[0], path->slots[0]);
> + return 0;
> +}
>
