Re: [PATCH 10/12] KVM: cleanup and add shortcuts to kvm_range_has_memory_attributes()

Michael Roth
2024-07-17T22:50:13Z

On Thu, Jul 11, 2024 at 06:27:53PM -0400, Paolo Bonzini wrote:
> Use a guard to simplify early returns, and add two more easy
> shortcuts. If the requested attributes are invalid, the attributes
> xarray will never show them as set. And if testing a single page,
> kvm_get_memory_attributes() is more efficient.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> virt/kvm/kvm_main.c | 42 ++++++++++++++++++++----------------------
> 1 file changed, 20 insertions(+), 22 deletions(-)
>
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index f817ec66c85f..8ab9d8ff7b74 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -2392,6 +2392,14 @@ static int kvm_vm_ioctl_clear_dirty_log(struct kvm *kvm,
> #endif /* CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT */
>
> #ifdef CONFIG_KVM_GENERIC_MEMORY_ATTRIBUTES
> +static u64 kvm_supported_mem_attributes(struct kvm *kvm)
> +{
> + if (!kvm || kvm_arch_has_private_mem(kvm))
> + return KVM_MEMORY_ATTRIBUTE_PRIVATE;
> +
> + return 0;
> +}
> +
> /*
> * Returns true if _all_ gfns in the range [@start, @end) have attributes
> * matching @attrs.
> @@ -2400,40 +2408,30 @@ bool kvm_range_has_memory_attributes(struct kvm *kvm, gfn_t start, gfn_t end,
> unsigned long attrs)
> {
> XA_STATE(xas, &kvm->mem_attr_array, start);
> + unsigned long mask = kvm_supported_mem_attributes(kvm);;

Extra semicolon.

Otherwise:

Reviewed-by: Michael Roth <michael.roth@amd.com>