[PATCH 3/4] KVM: selftests: Use asserting kvm_ioctl() macros when getting ARM page sizes

From: Sean Christopherson
Date: Thu Aug 03 2023 - 20:43:37 EST


Use kvm_ioctl() instead of open coding equivalent ioctl()+TEST_ASSERT()
calls when getting the support page sizes on ARM. The macro usage is a
little funky since the "kvm_fd" parameter implies an actual /dev/kvm fd,
but on the other hand the code is invoking KVM ioctl()s.

Alternatively, the core utilities could expose a vm_open()+vm_close()
pair so that the ARM code could create a dummy, on-stack VM+vCPU pair and
use {vm,vcpu}_ioctl() as appropriate. But the odds of something breaking
due to oddball, partial usage of kvm_vm and kvm_vcpu structures is much
higher than realizing meaningful benefit from using {vm,vcpu}_ioctl().

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
.../selftests/kvm/lib/aarch64/processor.c | 18 ++++++------------
1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/tools/testing/selftests/kvm/lib/aarch64/processor.c b/tools/testing/selftests/kvm/lib/aarch64/processor.c
index 3a0259e25335..afec1a30916f 100644
--- a/tools/testing/selftests/kvm/lib/aarch64/processor.c
+++ b/tools/testing/selftests/kvm/lib/aarch64/processor.c
@@ -496,7 +496,7 @@ void aarch64_get_supported_page_sizes(uint32_t ipa,
bool *ps4k, bool *ps16k, bool *ps64k)
{
struct kvm_vcpu_init preferred_init;
- int kvm_fd, vm_fd, vcpu_fd, err;
+ int kvm_fd, vm_fd, vcpu_fd;
uint64_t val;
struct kvm_one_reg reg = {
.id = KVM_ARM64_SYS_REG(SYS_ID_AA64MMFR0_EL1),
@@ -504,19 +504,13 @@ void aarch64_get_supported_page_sizes(uint32_t ipa,
};

kvm_fd = open_kvm_dev_path_or_exit();
- vm_fd = __kvm_ioctl(kvm_fd, KVM_CREATE_VM, (void *)(unsigned long)ipa);
- TEST_ASSERT(vm_fd >= 0, KVM_IOCTL_ERROR(KVM_CREATE_VM, vm_fd));
+ vm_fd = kvm_fd_ioctl(kvm_fd, KVM_CREATE_VM, (void *)(unsigned long)ipa);
+ vcpu_fd = kvm_fd_ioctl(vm_fd, KVM_CREATE_VCPU, (void *)0ul);

- vcpu_fd = ioctl(vm_fd, KVM_CREATE_VCPU, 0);
- TEST_ASSERT(vcpu_fd >= 0, KVM_IOCTL_ERROR(KVM_CREATE_VCPU, vcpu_fd));
+ kvm_ioctl(vm_fd, KVM_ARM_PREFERRED_TARGET, &preferred_init);
+ kvm_ioctl(vcpu_fd, KVM_ARM_VCPU_INIT, &preferred_init);

- err = ioctl(vm_fd, KVM_ARM_PREFERRED_TARGET, &preferred_init);
- TEST_ASSERT(err == 0, KVM_IOCTL_ERROR(KVM_ARM_PREFERRED_TARGET, err));
- err = ioctl(vcpu_fd, KVM_ARM_VCPU_INIT, &preferred_init);
- TEST_ASSERT(err == 0, KVM_IOCTL_ERROR(KVM_ARM_VCPU_INIT, err));
-
- err = ioctl(vcpu_fd, KVM_GET_ONE_REG, &reg);
- TEST_ASSERT(err == 0, KVM_IOCTL_ERROR(KVM_GET_ONE_REG, vcpu_fd));
+ kvm_ioctl(vcpu_fd, KVM_GET_ONE_REG, &reg);

*ps4k = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64MMFR0_TGRAN4), val) != 0xf;
*ps64k = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64MMFR0_TGRAN64), val) == 0;
--
2.41.0.585.gd2178a4bd4-goog