On Tue 05-11-19 23:02:39, Matthew Bobrowski wrote:
> + if (ret >= 0 && iov_iter_count(from)) {
> + ssize_t err;
> + loff_t endbyte;
> +
> + offset = iocb->ki_pos;
> + err = ext4_buffered_write_iter(iocb, from);
> + if (err < 0)
> + return err;
> +
> + /*
> + * We need to ensure that the pages within the page cache for
> + * the range covered by this I/O are written to disk and
> + * invalidated. This is in attempt to preserve the expected
> + * direct I/O semantics in the case we fallback to buffered I/O
> + * to complete off the I/O request.
> + */
> + ret += err;
> + endbyte = offset + ret - 1;
^^ err here?
Otherwise you would write out and invalidate too much AFAICT - the 'offset'
is position just before we fall back to buffered IO. Otherwise this hunk
looks good to me.
> + err = filemap_write_and_wait_range(iocb->ki_filp->f_mapping,
> + offset, endbyte);
> + if (!err)
> + invalidate_mapping_pages(iocb->ki_filp->f_mapping,
> + offset >> PAGE_SHIFT,
> + endbyte >> PAGE_SHIFT);
> + }
> +
> + return ret;
> +}
> +
Honza
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
