KVM: selftests: arm64: Add support for various modes with 16kB page size

The 16kB page size is not a popular choice, due to only a few CPUs
actually implementing support for it. However, it can lead to some
interesting performance improvements given the right uarch choices.

Add support for this page size for various PA/VA combinations.

Signed-off-by: Marc Zyngier <[email protected]>
Reviewed-by: Andrew Jones <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: Marc Zyngier

tools/testing/selftests/kvm/include/kvm_util.h

@@ -42,14 +42,18 @@ enum vm_guest_mode {
 	VM_MODE_P52V48_4K,
 	VM_MODE_P52V48_64K,
 	VM_MODE_P48V48_4K,
+	VM_MODE_P48V48_16K,
 	VM_MODE_P48V48_64K,
 	VM_MODE_P40V48_4K,
+	VM_MODE_P40V48_16K,
 	VM_MODE_P40V48_64K,
 	VM_MODE_PXXV48_4K,	/* For 48bits VA but ANY bits PA */
 	VM_MODE_P47V64_4K,
 	VM_MODE_P44V64_4K,
 	VM_MODE_P36V48_4K,
+	VM_MODE_P36V48_16K,
 	VM_MODE_P36V48_64K,
+	VM_MODE_P36V47_16K,
 	NUM_VM_MODES,
 };
 

tools/testing/selftests/kvm/lib/aarch64/processor.c

@@ -252,6 +252,12 @@ void aarch64_vcpu_setup(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_vcpu_init
 	case VM_MODE_P36V48_64K:
 		tcr_el1 |= 1ul << 14; /* TG0 = 64KB */
 		break;
+	case VM_MODE_P48V48_16K:
+	case VM_MODE_P40V48_16K:
+	case VM_MODE_P36V48_16K:
+	case VM_MODE_P36V47_16K:
+		tcr_el1 |= 2ul << 14; /* TG0 = 16KB */
+		break;
 	case VM_MODE_P48V48_4K:
 	case VM_MODE_P40V48_4K:
 	case VM_MODE_P36V48_4K:
@@ -267,15 +273,19 @@ void aarch64_vcpu_setup(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_vcpu_init
 		tcr_el1 |= 6ul << 32; /* IPS = 52 bits */
 		break;
 	case VM_MODE_P48V48_4K:
+	case VM_MODE_P48V48_16K:
 	case VM_MODE_P48V48_64K:
 		tcr_el1 |= 5ul << 32; /* IPS = 48 bits */
 		break;
 	case VM_MODE_P40V48_4K:
+	case VM_MODE_P40V48_16K:
 	case VM_MODE_P40V48_64K:
 		tcr_el1 |= 2ul << 32; /* IPS = 40 bits */
 		break;
 	case VM_MODE_P36V48_4K:
+	case VM_MODE_P36V48_16K:
 	case VM_MODE_P36V48_64K:
+	case VM_MODE_P36V47_16K:
 		tcr_el1 |= 1ul << 32; /* IPS = 36 bits */
 		break;
 	default:

tools/testing/selftests/kvm/lib/guest_modes.c

@@ -29,17 +29,21 @@ void guest_modes_append_default(void)
 			guest_mode_append(VM_MODE_P52V48_64K, ps64k, ps64k);
 		if (limit >= 48) {
 			guest_mode_append(VM_MODE_P48V48_4K, ps4k, ps4k);
+			guest_mode_append(VM_MODE_P48V48_16K, ps16k, ps16k);
 			guest_mode_append(VM_MODE_P48V48_64K, ps64k, ps64k);
 		}
 		if (limit >= 40) {
 			guest_mode_append(VM_MODE_P40V48_4K, ps4k, ps4k);
+			guest_mode_append(VM_MODE_P40V48_16K, ps16k, ps16k);
 			guest_mode_append(VM_MODE_P40V48_64K, ps64k, ps64k);
 			if (ps4k)
 				vm_mode_default = VM_MODE_P40V48_4K;
 		}
 		if (limit >= 36) {
 			guest_mode_append(VM_MODE_P36V48_4K, ps4k, ps4k);
+			guest_mode_append(VM_MODE_P36V48_16K, ps16k, ps16k);
 			guest_mode_append(VM_MODE_P36V48_64K, ps64k, ps64k);
+			guest_mode_append(VM_MODE_P36V47_16K, ps16k, ps16k);
 		}
 
 		/*

tools/testing/selftests/kvm/lib/kvm_util.c

@@ -166,14 +166,18 @@ const char *vm_guest_mode_string(uint32_t i)
 		[VM_MODE_P52V48_4K]	= "PA-bits:52,  VA-bits:48,  4K pages",
 		[VM_MODE_P52V48_64K]	= "PA-bits:52,  VA-bits:48, 64K pages",
 		[VM_MODE_P48V48_4K]	= "PA-bits:48,  VA-bits:48,  4K pages",
+		[VM_MODE_P48V48_16K]	= "PA-bits:48,  VA-bits:48, 16K pages",
 		[VM_MODE_P48V48_64K]	= "PA-bits:48,  VA-bits:48, 64K pages",
 		[VM_MODE_P40V48_4K]	= "PA-bits:40,  VA-bits:48,  4K pages",
+		[VM_MODE_P40V48_16K]	= "PA-bits:40,  VA-bits:48, 16K pages",
 		[VM_MODE_P40V48_64K]	= "PA-bits:40,  VA-bits:48, 64K pages",
 		[VM_MODE_PXXV48_4K]	= "PA-bits:ANY, VA-bits:48,  4K pages",
 		[VM_MODE_P47V64_4K]	= "PA-bits:47,  VA-bits:64,  4K pages",
 		[VM_MODE_P44V64_4K]	= "PA-bits:44,  VA-bits:64,  4K pages",
 		[VM_MODE_P36V48_4K]	= "PA-bits:36,  VA-bits:48,  4K pages",
+		[VM_MODE_P36V48_16K]	= "PA-bits:36,  VA-bits:48, 16K pages",
 		[VM_MODE_P36V48_64K]	= "PA-bits:36,  VA-bits:48, 64K pages",
+		[VM_MODE_P36V47_16K]	= "PA-bits:36,  VA-bits:47, 16K pages",
 	};
 	_Static_assert(sizeof(strings)/sizeof(char *) == NUM_VM_MODES,
 		       "Missing new mode strings?");
@@ -187,14 +191,18 @@ const struct vm_guest_mode_params vm_guest_mode_params[] = {
 	[VM_MODE_P52V48_4K]	= { 52, 48,  0x1000, 12 },
 	[VM_MODE_P52V48_64K]	= { 52, 48, 0x10000, 16 },
 	[VM_MODE_P48V48_4K]	= { 48, 48,  0x1000, 12 },
+	[VM_MODE_P48V48_16K]	= { 48, 48,  0x4000, 14 },
 	[VM_MODE_P48V48_64K]	= { 48, 48, 0x10000, 16 },
 	[VM_MODE_P40V48_4K]	= { 40, 48,  0x1000, 12 },
+	[VM_MODE_P40V48_16K]	= { 40, 48,  0x4000, 14 },
 	[VM_MODE_P40V48_64K]	= { 40, 48, 0x10000, 16 },
 	[VM_MODE_PXXV48_4K]	= {  0,  0,  0x1000, 12 },
 	[VM_MODE_P47V64_4K]	= { 47, 64,  0x1000, 12 },
 	[VM_MODE_P44V64_4K]	= { 44, 64,  0x1000, 12 },
 	[VM_MODE_P36V48_4K]	= { 36, 48,  0x1000, 12 },
+	[VM_MODE_P36V48_16K]	= { 36, 48,  0x4000, 14 },
 	[VM_MODE_P36V48_64K]	= { 36, 48, 0x10000, 16 },
+	[VM_MODE_P36V47_16K]	= { 36, 47,  0x4000, 14 },
 };
 _Static_assert(sizeof(vm_guest_mode_params)/sizeof(struct vm_guest_mode_params) == NUM_VM_MODES,
 	       "Missing new mode params?");
@@ -263,6 +271,14 @@ struct kvm_vm *vm_create(enum vm_guest_mode mode, uint64_t phy_pages, int perm)
 	case VM_MODE_P36V48_64K:
 		vm->pgtable_levels = 3;
 		break;
+	case VM_MODE_P48V48_16K:
+	case VM_MODE_P40V48_16K:
+	case VM_MODE_P36V48_16K:
+		vm->pgtable_levels = 4;
+		break;
+	case VM_MODE_P36V47_16K:
+		vm->pgtable_levels = 3;
+		break;
 	case VM_MODE_PXXV48_4K:
 #ifdef __x86_64__
 		kvm_get_cpu_address_width(&vm->pa_bits, &vm->va_bits);