On 2018/1/4 14:16, Jaegeuk Kim wrote:
> On 01/04, Chao Yu wrote:
>> On 2018/1/4 4:12, Jaegeuk Kim wrote:
>>> On 01/03, Chao Yu wrote:
>>>> If we need an array with variable size in the end of structure, we
>>>> can utilize flexible array feature which is supported in C99, so
>>>> let's change sit_nat_version_bitmap[] to flexible array in struct
>>>> f2fs_checkpoint for readability.
>>>>
>>>> Signed-off-by: Chao Yu <yuch...@huawei.com>
>>>> ---
>>>> fs/f2fs/f2fs.h | 4 ++--
>>>> include/linux/f2fs_fs.h | 2 +-
>>>> 2 files changed, 3 insertions(+), 3 deletions(-)
>>>>
>>>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>>>> index 83d1f697388b..ad19d29688ae 100644
>>>> --- a/fs/f2fs/f2fs.h
>>>> +++ b/fs/f2fs/f2fs.h
>>>> @@ -1719,13 +1719,13 @@ static inline void *__bitmap_ptr(struct
>>>> f2fs_sb_info *sbi, int flag)
>>>>
>>>> if (__cp_payload(sbi) > 0) {
>>>> if (flag == NAT_BITMAP)
>>>> - return &ckpt->sit_nat_version_bitmap;
>>>> + return ckpt->sit_nat_version_bitmap;
>>>> else
>>>> return (unsigned char *)ckpt + F2FS_BLKSIZE;
>>>> } else {
>>>> offset = (flag == NAT_BITMAP) ?
>>>> le32_to_cpu(ckpt->sit_ver_bitmap_bytesize) : 0;
>>>> - return &ckpt->sit_nat_version_bitmap + offset;
>>>> + return ckpt->sit_nat_version_bitmap + offset;
>>>> }
>>>> }
>>>>
>>>> diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
>>>> index 43e98d30d2df..564f65fc192f 100644
>>>> --- a/include/linux/f2fs_fs.h
>>>> +++ b/include/linux/f2fs_fs.h
>>>> @@ -157,7 +157,7 @@ struct f2fs_checkpoint {
>>>> unsigned char alloc_type[MAX_ACTIVE_LOGS];
>>>>
>>>> /* SIT and NAT version bitmap */
>>>> - unsigned char sit_nat_version_bitmap[1];
>>>> + unsigned char sit_nat_version_bitmap[];
>>>
>>> I cannot find any benefit to do this. Moreover, it just makes the header
>>
>> I intend to change both kernel and tools, sorry, I didn't send out the
>> patch on tools. Anyway, I think it could be used to avoid checkpoint
>> structure size calculation by "sizeof(struct checkpoint) - 1", with the
>> patch, readability can be improved. Right?
>
> I don't think so. It's even defined only in f2fs-tools, and well covered by a
> macro. There's no reason to spend time to sync it between f2fs and f2fs-tools.
OK, this is only about readability, it's really not a big deal to drop this
patch.
Thanks,
>
>>
>> Thanks,
>>
>>> structure be different from the one in f2fs-tools.
>>>
>>>> } __packed;
>>>>
>>>> /*
>>>> --
>>>> 2.15.0.55.gc2ece9dc4de6
>>>
>>> .
>>>
>
> .
>
