Re: [PATCH v3 3/9] xen/balloon: Share common memory reservation routines

[Boris Ostrovsky]

On 06/12/2018 09:41 AM, Oleksandr Andrushchenko wrote:



One more thing: please add a comment here saying that frames array is 
array of PFNs (in Xen granularity), which is what 
XENMEM_populate_physmap requires. And remove (or update to name the 
actual call you are making) the corresponding comment in 
increase_reservation().


> +
> +int xenmem_reservation_increase(int count, xen_pfn_t *frames)
> +{
> +	struct xen_memory_reservation reservation = {
> +		.address_bits = 0,
> +		.extent_order = EXTENT_ORDER,
> +		.domid        = DOMID_SELF
> +	};
> +
> +	set_xen_guest_handle(reservation.extent_start, frames);
> +	reservation.nr_extents = count;
> +	return HYPERVISOR_memory_op(XENMEM_populate_physmap, &reservation);
> +}
> +EXPORT_SYMBOL_GPL(xenmem_reservation_increase);


And similarly, here we are requesting GFNs, and update 
decrease_reservation().


-boris

> +
> +int xenmem_reservation_decrease(int count, xen_pfn_t *frames)
> +{
> +	struct xen_memory_reservation reservation = {
> +		.address_bits = 0,
> +		.extent_order = EXTENT_ORDER,
> +		.domid        = DOMID_SELF
> +	};
> +
> +	set_xen_guest_handle(reservation.extent_start, frames);
> +	reservation.nr_extents = count;
> +	return HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);