Re: [PATCH] f2fs: restrict write IO alignment condition

[Chao Yu]

On 2017/3/11 2:50, Jaegeuk Kim wrote:
> On 03/10, Chao Yu wrote:
>> We should only align start offset of bio with defined IO_SIZE for below
>> conditions:
>> a. write IOs
>> b. Out-place-update
>> c. non-meta page
>>
>> Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
>> ---
>>  fs/f2fs/data.c | 4 +++-
>>  1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
>> index 1375fef11146..3e6b0cc5e36a 100644
>> --- a/fs/f2fs/data.c
>> +++ b/fs/f2fs/data.c
>> @@ -395,7 +395,9 @@ int f2fs_submit_page_mbio(struct f2fs_io_info *fio)
>>  		__submit_merged_bio(io);
>>  alloc_new:
>>  	if (io->bio == NULL) {
>> -		if ((fio->type == DATA || fio->type == NODE) &&
>> +		if (!is_read && (fio->type == DATA || fio->type == NODE) &&
>> +				bio_page->mapping != META_MAPPING(sbi) &&
> 
> BUG_ON(), since it's covered by fio->type == DATA || fio->type == NODE.

Oh, the condition I added here is wrong, since move_encrypted_block will add a
meta page into DATA type bio cache, also we can not add a BUG_ON here.

> 
>> +				fio->new_blkaddr != fio->old_blkaddr &&
> 
> BUG_ON(), since LFS mount option doesn't allow any in-place updates.

You're right. :)

> 
>>  				fio->new_blkaddr & F2FS_IO_SIZE_MASK(sbi)) {
> 
> So, is_read is worth to check?

Yes.

I will fix them and resend v2.

Thanks,

> 
> Thanks,
> 
>>  			err = -EAGAIN;
>>  			if (!is_read)
>> -- 
>> 2.8.2.295.g3f1c1d0
> 
> .
>