[4/4] powerpc/mm: Split hash page table sizing heuristic into a helper

[Michael Ellerman]

On Tue, 2016-09-02 at 03:32:43 UTC, David Gibson wrote:
> htab_get_table_size() either retrieve the size of the hash page table (HPT)
> from the device tree - if the HPT size is determined by firmware - or
> uses a heuristic to determine a good size based on RAM size if the kernel
> is responsible for allocating the HPT.
> 
> To support a PAPR extension allowing resizing of the HPT, we're going to
> want the memory size -> HPT size logic elsewhere, so split it out into a
> helper function.
> 
> Signed-off-by: David Gibson <david at gibson.dropbear.id.au>
> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/5c3c7ede2bdcb85fa2fd51c814

I reworded one comment a little, from:

	/* 2^11 PTEGS / 2^18 bytes is the minimum htab size permitted
	 * by the architecture */

to:
	/*
	 * 2^11 PTEGS of 128 bytes each, ie. 2^18 bytes is the minimum htab
	 * size permitted by the architecture.
	 */

To avoid any confusion about the "/" referring to division.

cheers