RE: RE: [PATCH v0] f2fs: allow direct read for zoned device

From: Eunhee Rho
Date: Mon Aug 01 2022 - 00:07:26 EST


>On 07/29, Eunhee Rho wrote:
>> For zoned devices, f2fs forbids direct IO and forces buffered IO
>> to serialize write IOs. However, the constraint does not apply to
>> read IOs.
>>
>> Signed-off-by: Eunhee Rho <eunhee83.rho@xxxxxxxxxxx>
>> ---
>> fs/f2fs/f2fs.h | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>> index d0f428aef34b..f69731f17402 100644
>> --- a/fs/f2fs/f2fs.h
>> +++ b/fs/f2fs/f2fs.h
>> @@ -4471,7 +4471,7 @@ static inline bool f2fs_force_buffered_io(struct inode *inode,
>> * for blkzoned device, fallback direct IO to buffered IO, so
>> * all IOs can be serialized by log-structured write.
>> */
>> - if (f2fs_sb_has_blkzoned(sbi))
>> + if (f2fs_sb_has_blkzoned(sbi) && (rw == WRITE))
>> return true;
>
>Actually we don't need to check the device type, but rely on the
>filesystem allocation policy like the below lfs mode. Can we remove this
>line simply?
>
>> if (f2fs_lfs_mode(sbi) && (rw == WRITE)) {
>> if (block_unaligned_IO(inode, iocb, iter))
>> --
>> 2.25.1
>

Yes, I will reflect on the next patch.
Thanks.