ARM: KVM: add architecture specific hook for capabilities

Most of the capabilities are common to both arm and arm64, but
we still need to handle the exceptions.

Introduce kvm_arch_dev_ioctl_check_extension, which both architectures
implement (in the 32bit case, it just returns 0).

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu>

2 files changed, 6 insertions, 1 deletions

diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 6c2a35da867e..dcfcbf59fceb 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -214,6 +214,11 @@ static inline void __cpu_init_hyp_mode(unsigned long long boot_pgd_ptr,
         kvm_call_hyp((void*)hyp_stack_ptr, vector_ptr, pgd_ptr);
 }
 
+static inline int kvm_arch_dev_ioctl_check_extension(long ext)
+{
+        return 0;
+}
+
 int kvm_perf_init(void);
 int kvm_perf_teardown(void);
 
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 6ea2aed0d29f..cc67cafc5b87 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -206,7 +206,7 @@ int kvm_dev_ioctl_check_extension(long ext)
                 r = KVM_MAX_VCPUS;
                 break;
         default:
-                r = 0;
+                r = kvm_arch_dev_ioctl_check_extension(ext);
                 break;
         }
         return r;