Re: [PATCHv2 3/5] xfs: report direct io attributes through file_getattr

[Christoph Hellwig <hch@infradead.org>]

On Tue, Jul 14, 2026 at 03:09:57PM -0600, Keith Busch wrote:
> +void bdev_dio_align(struct block_device *bdev, struct fs_dio_align *align)

Nit: I'd usually pass the filled in structure before the source of the
information.

> +	case FS_IOC_GETDIOALIGN: {
> +		struct fs_dio_align align = {};
> +
> +		bdev_dio_align(bdev, &align);
> +		return copy_to_user(argp, &align, sizeof(align)) ? -EFAULT : 0;
> +	}

... and I'd probably split this into a little helper function as the
ioctl handlers sooner or later become a mess otherwise.

> +	case FS_IOC_GETDIOALIGN: {
> +		struct fs_dio_align	align = {};
> +
> +		if (!S_ISREG(inode->i_mode))
> +			return -ENOTTY;
> +		bdev_dio_align(xfs_inode_buftarg(ip)->bt_bdev, &align);
> +		if (xfs_is_cow_inode(ip))
> +			align.dio_offset_align = xfs_inode_alloc_unitsize(ip);
> +		if (copy_to_user(arg, &align, sizeof(align)))
> +			return -EFAULT;

Same here.

Otherwise this looks good to me.