[PATCH 3/5] xfs: prevent extsize alignment from exceeding maximum extent size

[Christoph Hellwig]

> +					/*
> +					 * make sure we don't exceed a single
> +					 * extent length when we align the
> +					 * extent by reducing length we are
> +					 * going to allocate by the maximum
> +					 * amount extent size aligment may
> +					 * require.
> +					alen = (xfs_extlen_t)XFS_FILBLKS_MIN(
> +							len,
> +						MAXEXTLEN - (2 * extsz - 1));
> +					 */

This essentially just adds a comment, given that the new code is inside
the bracing.  Also the xfs_extlen_t cast seems pointless.  The C type
promotion rules do just fine for going down from a 64bit type to a 32bit
one, as long as the results fit into the latter - which they always do
here.