KVM: selftests: Fix alignment in virt_arch_pgd_alloc() and vm_vaddr_alloc()

Refactor virt_arch_pgd_alloc() and vm_vaddr_alloc() in both RISC-V and
aarch64 to fix the alignment of parameters in a couple of calls. This will
make it easier to fix the alignment in a future commit that adds an extra
parameter (that happens to be very long).

No functional change intended.
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Ricardo Koller <ricarkol@google.com>
Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221017195834.2295901-9-ricarkol@google.com

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

@@ -76,13 +76,14 @@ static uint64_t __maybe_unused ptrs_per_pte(struct kvm_vm *vm)
 
 void virt_arch_pgd_alloc(struct kvm_vm *vm)
 {
-	if (!vm->pgd_created) {
-		vm_paddr_t paddr = vm_phy_pages_alloc(vm,
-			page_align(vm, ptrs_per_pgd(vm) * 8) / vm->page_size,
-			KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
-		vm->pgd = paddr;
-		vm->pgd_created = true;
-	}
+	size_t nr_pages = page_align(vm, ptrs_per_pgd(vm) * 8) / vm->page_size;
+
+	if (vm->pgd_created)
+		return;
+
+	vm->pgd = vm_phy_pages_alloc(vm, nr_pages,
+				     KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
+	vm->pgd_created = true;
 }
 
 static void _virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
@@ -325,13 +326,15 @@ void vcpu_arch_dump(FILE *stream, struct kvm_vcpu *vcpu, uint8_t indent)
 struct kvm_vcpu *aarch64_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id,
 				  struct kvm_vcpu_init *init, void *guest_code)
 {
-	size_t stack_size = vm->page_size == 4096 ?
-					DEFAULT_STACK_PGS * vm->page_size :
-					vm->page_size;
-	uint64_t stack_vaddr = vm_vaddr_alloc(vm, stack_size,
-					      DEFAULT_ARM64_GUEST_STACK_VADDR_MIN);
+	size_t stack_size;
+	uint64_t stack_vaddr;
 	struct kvm_vcpu *vcpu = __vm_vcpu_add(vm, vcpu_id);
 
+	stack_size = vm->page_size == 4096 ? DEFAULT_STACK_PGS * vm->page_size :
+					     vm->page_size;
+	stack_vaddr = vm_vaddr_alloc(vm, stack_size,
+				     DEFAULT_ARM64_GUEST_STACK_VADDR_MIN);
+
 	aarch64_vcpu_setup(vcpu, init);
 
 	vcpu_set_reg(vcpu, ARM64_CORE_REG(sp_el1), stack_vaddr + stack_size);

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

@@ -55,13 +55,14 @@ static uint64_t pte_index(struct kvm_vm *vm, vm_vaddr_t gva, int level)
 
 void virt_arch_pgd_alloc(struct kvm_vm *vm)
 {
-	if (!vm->pgd_created) {
-		vm_paddr_t paddr = vm_phy_pages_alloc(vm,
-			page_align(vm, ptrs_per_pte(vm) * 8) / vm->page_size,
-			KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
-		vm->pgd = paddr;
-		vm->pgd_created = true;
-	}
+	size_t nr_pages = page_align(vm, ptrs_per_pte(vm) * 8) / vm->page_size;
+
+	if (vm->pgd_created)
+		return;
+
+	vm->pgd = vm_phy_pages_alloc(vm, nr_pages,
+				     KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
+	vm->pgd_created = true;
 }
 
 void virt_arch_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr)
@@ -279,15 +280,17 @@ struct kvm_vcpu *vm_arch_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id,
 				  void *guest_code)
 {
 	int r;
-	size_t stack_size = vm->page_size == 4096 ?
-					DEFAULT_STACK_PGS * vm->page_size :
-					vm->page_size;
-	unsigned long stack_vaddr = vm_vaddr_alloc(vm, stack_size,
-					DEFAULT_RISCV_GUEST_STACK_VADDR_MIN);
+	size_t stack_size;
+	unsigned long stack_vaddr;
 	unsigned long current_gp = 0;
 	struct kvm_mp_state mps;
 	struct kvm_vcpu *vcpu;
 
+	stack_size = vm->page_size == 4096 ? DEFAULT_STACK_PGS * vm->page_size :
+					     vm->page_size;
+	stack_vaddr = vm_vaddr_alloc(vm, stack_size,
+				     DEFAULT_RISCV_GUEST_STACK_VADDR_MIN);
+
 	vcpu = __vm_vcpu_add(vm, vcpu_id);
 	riscv_vcpu_mmu_setup(vcpu);