> -----邮件原件----- > 发件人: Yuezhang.Mo@xxxxxxxx <Yuezhang.Mo@xxxxxxxx> > 发送时间: 2025年6月17日 11:32 > 收件人: 张政旭 (Zhengxu Zhang) <Zhengxu.Zhang@xxxxxxxxxx>; Cixi Geng > <cixi.geng@xxxxxxxxx>; linkinjeon@xxxxxxxxxx; sj1557.seo@xxxxxxxxxxx > 抄送: linux-fsdevel@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; 王皓 (Hao_hao > Wang) <Hao_hao.Wang@xxxxxxxxxx> > 主题: Re: [PATCH] exfat: fdatasync flag should be same like generic_write_sync() > > > > > > > --- a/fs/exfat/file.c > > > > +++ b/fs/exfat/file.c > > > > @@ -625,7 +625,7 @@ static ssize_t exfat_file_write_iter(struct kiocb *iocb, > > > > struct iov_iter *iter) > > > > > > > > if (iocb_is_dsync(iocb) && iocb->ki_pos > pos) { > > > > ssize_t err = vfs_fsync_range(file, pos, iocb->ki_pos - 1, > > > > - iocb->ki_flags & IOCB_SYNC); > > > > + (iocb->ki_flags & IOCB_SYNC) ? 0 : 1); > > > > > > How about calling generic_write_sync() instead of vfs_fsync_range(), like in > > > generic_file_write_iter()? > > The second arg of vfs_fsync_range "pos" maybe changed by valid_size (if pos > > valid_size). > > It can not replace by iocb->ki_pos - ret (ret by __generic_file_write_iter). > > So current way maybe better. > > Here we synchronize the areas written by exfat_extend_valid_size() and > __generic_file_write_iter() if valid_size < pos. > > The lengths of these two write areas are 'pos-valid_size' and 'ret'. > We can use generic_write_sync() and pass it the sum of these two lengths. > > Of course, regardless of whether valid_size < pos, exfat_file_write_iter() only > needs to return the length written by __generic_file_write_iter(). I try the sum of 'pos-valid_size' and 'ret',like this: if (iocb->ki_pos > pos) { ssize_t err = generic_write_sync(iocb, pos + ret - valid_size); if (err < 0) return err; } The test crashed, that maybe io error. So I try a simple way that use iocb->ki_pos - pos. like this: if (iocb->ki_pos > pos) { ssize_t err = generic_write_sync(iocb, iocb->ki_pos - pos); if (err < 0) return err; } The test pass. pls check again.