On 2020/2/14 下午5:25, Nikolay Borisov wrote:
>
>
> 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.
Even when we could hit error in this case?
In the next patch, you would see we handle end of backrefs and error
different.
Thus I don't think it's a good idea to make it bool.
Thanks,
Qu
>
>> + 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;
>> +}
>>
