Re: [PATCH 12/15] btrfs: Use iomap_dio_rw for performing direct I/O writes

[Christoph Hellwig <hch@lst.de>]

Lots of lines > 80 chars, and various indentation errors, I'm not
going to point them out invdividually.


>  ssize_t btrfs_dio_iomap_read(struct kiocb *iocb, struct iov_iter *to)
> @@ -437,7 +536,58 @@ ssize_t btrfs_dio_iomap_read(struct kiocb *iocb, struct iov_iter *to)
>  	struct inode *inode = file_inode(iocb->ki_filp);
>  	ssize_t ret;
>  	inode_lock_shared(inode);
> -	ret = iomap_dio_rw(iocb, to, &btrfs_dio_iomap_ops, NULL);
> +	ret = iomap_dio_rw(iocb, to, &btrfs_dio_iomap_ops, &btrfs_dops);

So the read did not previously need the submit callback, but it does
now?  That seems a little odd.

>  	inode_unlock_shared(inode);
>  	return ret;
>  }
> +
> +ssize_t btrfs_dio_iomap_write(struct kiocb *iocb, struct iov_iter *from)

Why not just brfs_dio_write?

> +	written = iomap_dio_rw(iocb, from, &btrfs_dio_iomap_ops, &btrfs_dops);
> +	if (written < count) {
> +		ssize_t done = (written < 0) ? 0 : written;
> +		btrfs_delalloc_release_space(inode, data_reserved, pos, count - done,
> +	                       true);

Line > 80 characters.

> +out:
> +	if (written > 0 && iocb->ki_pos > i_size_read(inode))
> +			i_size_write(inode, iocb->ki_pos);

Odd indentation.

> +	return written ? written : err;

But not:

	if (!written)
		return err;

	if (iocb->ki_pos > i_size_read(inode))
		i_size_write(inode, iocb->ki_pos);
	return written;