> -----Original Message-----
> From: Namjae Jeon <linkinjeon@xxxxxxxxxx>
> Sent: Tuesday, December 5, 2023 11:30 AM
> To: Mo, Yuezhang <Yuezhang.Mo@xxxxxxxx>
> Cc: sj1557.seo@xxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; Wu, Andy
> <Andy.Wu@xxxxxxxx>; Aoyama, Wataru (SGC) <Wataru.Aoyama@xxxxxxxx>;
> cpgs@xxxxxxxxxxx
> Subject: Re: [PATCH v5 1/2] exfat: change to get file size from DataLength
>
> > +static int exfat_file_zeroed_range(struct file *file, loff_t start, loff_t
> > end)
> > +{
> > + int err;
> > + struct inode *inode = file_inode(file);
> > + struct exfat_inode_info *ei = EXFAT_I(inode);
> > + struct address_space *mapping = inode->i_mapping;
> > + const struct address_space_operations *ops = mapping->a_ops;
> > +
> > + while (start < end) {
> > + u32 zerofrom, len;
> > + struct page *page = NULL;
> > +
> > + zerofrom = start & (PAGE_SIZE - 1);
> > + len = PAGE_SIZE - zerofrom;
> > + if (start + len > end)
> > + len = end - start;
> > +
> > + err = ops->write_begin(file, mapping, start, len, &page, NULL);
> Is there any reason why you don't use block_write_begin and
> generic_write_end() ?
>
> Thanks.
If use block_write_begin(), we need to remove 'static' from exfat_get_block(),
use ops->write_begin() and ops->write_end() makes the function more generic,
maybe we can rename this function to generic_write_zero() and move it to
fs/buffer.c.
And ei->valid_size had updated in ops->write_end(), it is unneeded to update in
this function.
> > + if (err)
> > + goto out;
> > +
> > + zero_user_segment(page, zerofrom, zerofrom + len);
> > +
> > + err = ops->write_end(file, mapping, start, len, len, page, NULL);
> > + if (err < 0)
> > + goto out;
> > + start += len;
> > +
> > + balance_dirty_pages_ratelimited(mapping);
> > + cond_resched();
> > + }
> > +
> > + ei->valid_size = end;
> > + mark_inode_dirty(inode);
> > +
> > +out:
> > + return err;
> > +}
