KVM: x86: Modify struct kvm_nested_state to have explicit fields for data

Improve the KVM_{GET,SET}_NESTED_STATE structs by detailing the format
of VMX nested state data in a struct.

In order to avoid changing the ioctl values of
KVM_{GET,SET}_NESTED_STATE, there is a need to preserve
sizeof(struct kvm_nested_state). This is done by defining the data
struct as "data.vmx[0]". It was the most elegant way I found to
preserve struct size while still keeping struct readable and easy to
maintain. It does have a misfortunate side-effect that now it has to be
accessed as "data.vmx[0]" rather than just "data.vmx".

Because we are already modifying these structs, I also modified the
following:
* Define the "format" field values as macros.
* Rename vmcs_pa to vmcs12_pa for better readability.

Signed-off-by: Liran Alon <liran.alon@oracle.com>
[Remove SVM stubs, add KVM_STATE_NESTED_VMX_VMCS12_SIZE. - Paolo]
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

2 files changed, 22 insertions, 22 deletions

diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
index 7a0e64ccd6ff..24a8cd229df6 100644
--- a/tools/arch/x86/include/uapi/asm/kvm.h
+++ b/tools/arch/x86/include/uapi/asm/kvm.h
@@ -392,7 +392,7 @@ struct kvm_sync_regs {
 
 struct kvm_vmx_nested_state {
 	__u64 vmxon_pa;
-	__u64 vmcs_pa;
+	__u64 vmcs12_pa;
 
 	struct {
 		__u16 flags;
diff --git a/tools/testing/selftests/kvm/x86_64/vmx_set_nested_state_test.c b/tools/testing/selftests/kvm/x86_64/vmx_set_nested_state_test.c
index 9d62e2c7e024..0648fe6df5a8 100644
--- a/tools/testing/selftests/kvm/x86_64/vmx_set_nested_state_test.c
+++ b/tools/testing/selftests/kvm/x86_64/vmx_set_nested_state_test.c
@@ -75,7 +75,7 @@ void set_revision_id_for_vmcs12(struct kvm_nested_state *state,
 				u32 vmcs12_revision)
 {
 	/* Set revision_id in vmcs12 to vmcs12_revision. */
-	memcpy(state->data, &vmcs12_revision, sizeof(u32));
+	memcpy(&state->data, &vmcs12_revision, sizeof(u32));
 }
 
 void set_default_state(struct kvm_nested_state *state)
@@ -95,9 +95,9 @@ void set_default_vmx_state(struct kvm_nested_state *state, int size)
 			KVM_STATE_NESTED_EVMCS;
 	state->format = 0;
 	state->size = size;
-	state->vmx.vmxon_pa = 0x1000;
-	state->vmx.vmcs_pa = 0x2000;
-	state->vmx.smm.flags = 0;
+	state->hdr.vmx.vmxon_pa = 0x1000;
+	state->hdr.vmx.vmcs12_pa = 0x2000;
+	state->hdr.vmx.smm.flags = 0;
 	set_revision_id_for_vmcs12(state, VMCS12_REVISION);
 }
 
@@ -126,7 +126,7 @@ void test_vmx_nested_state(struct kvm_vm *vm)
 	 * is set to -1ull.
 	 */
 	set_default_vmx_state(state, state_sz);
-	state->vmx.vmxon_pa = -1ull;
+	state->hdr.vmx.vmxon_pa = -1ull;
 	test_nested_state(vm, state);
 
 	/* Enable VMX in the guest CPUID. */
@@ -134,14 +134,14 @@ void test_vmx_nested_state(struct kvm_vm *vm)
 
 	/* It is invalid to have vmxon_pa == -1ull and SMM flags non-zero. */
 	set_default_vmx_state(state, state_sz);
-	state->vmx.vmxon_pa = -1ull;
-	state->vmx.smm.flags = 1;
+	state->hdr.vmx.vmxon_pa = -1ull;
+	state->hdr.vmx.smm.flags = 1;
 	test_nested_state_expect_einval(vm, state);
 
 	/* It is invalid to have vmxon_pa == -1ull and vmcs_pa != -1ull. */
 	set_default_vmx_state(state, state_sz);
-	state->vmx.vmxon_pa = -1ull;
-	state->vmx.vmcs_pa = 0;
+	state->hdr.vmx.vmxon_pa = -1ull;
+	state->hdr.vmx.vmcs12_pa = 0;
 	test_nested_state_expect_einval(vm, state);
 
 	/*
@@ -149,13 +149,13 @@ void test_vmx_nested_state(struct kvm_vm *vm)
 	 * setting the nested state.
 	 */
 	set_default_vmx_state(state, state_sz);
-	state->vmx.vmxon_pa = -1ull;
-	state->vmx.vmcs_pa = -1ull;
+	state->hdr.vmx.vmxon_pa = -1ull;
+	state->hdr.vmx.vmcs12_pa = -1ull;
 	test_nested_state(vm, state);
 
 	/* It is invalid to have vmxon_pa set to a non-page aligned address. */
 	set_default_vmx_state(state, state_sz);
-	state->vmx.vmxon_pa = 1;
+	state->hdr.vmx.vmxon_pa = 1;
 	test_nested_state_expect_einval(vm, state);
 
 	/*
@@ -165,7 +165,7 @@ void test_vmx_nested_state(struct kvm_vm *vm)
 	set_default_vmx_state(state, state_sz);
 	state->flags = KVM_STATE_NESTED_GUEST_MODE  |
 		      KVM_STATE_NESTED_RUN_PENDING;
-	state->vmx.smm.flags = KVM_STATE_NESTED_SMM_GUEST_MODE;
+	state->hdr.vmx.smm.flags = KVM_STATE_NESTED_SMM_GUEST_MODE;
 	test_nested_state_expect_einval(vm, state);
 
 	/*
@@ -174,14 +174,14 @@ void test_vmx_nested_state(struct kvm_vm *vm)
 	 *	KVM_STATE_NESTED_SMM_VMXON
 	 */
 	set_default_vmx_state(state, state_sz);
-	state->vmx.smm.flags = ~(KVM_STATE_NESTED_SMM_GUEST_MODE |
+	state->hdr.vmx.smm.flags = ~(KVM_STATE_NESTED_SMM_GUEST_MODE |
 				KVM_STATE_NESTED_SMM_VMXON);
 	test_nested_state_expect_einval(vm, state);
 
 	/* Outside SMM, SMM flags must be zero. */
 	set_default_vmx_state(state, state_sz);
 	state->flags = 0;
-	state->vmx.smm.flags = KVM_STATE_NESTED_SMM_GUEST_MODE;
+	state->hdr.vmx.smm.flags = KVM_STATE_NESTED_SMM_GUEST_MODE;
 	test_nested_state_expect_einval(vm, state);
 
 	/* Size must be large enough to fit kvm_nested_state and vmcs12. */
@@ -191,8 +191,8 @@ void test_vmx_nested_state(struct kvm_vm *vm)
 
 	/* vmxon_pa cannot be the same address as vmcs_pa. */
 	set_default_vmx_state(state, state_sz);
-	state->vmx.vmxon_pa = 0;
-	state->vmx.vmcs_pa = 0;
+	state->hdr.vmx.vmxon_pa = 0;
+	state->hdr.vmx.vmcs12_pa = 0;
 	test_nested_state_expect_einval(vm, state);
 
 	/* The revision id for vmcs12 must be VMCS12_REVISION. */
@@ -205,16 +205,16 @@ void test_vmx_nested_state(struct kvm_vm *vm)
 	 * it again.
 	 */
 	set_default_vmx_state(state, state_sz);
-	state->vmx.vmxon_pa = -1ull;
-	state->vmx.vmcs_pa = -1ull;
+	state->hdr.vmx.vmxon_pa = -1ull;
+	state->hdr.vmx.vmcs12_pa = -1ull;
 	state->flags = 0;
 	test_nested_state(vm, state);
 	vcpu_nested_state_get(vm, VCPU_ID, state);
 	TEST_ASSERT(state->size >= sizeof(*state) && state->size <= state_sz,
 		    "Size must be between %d and %d.  The size returned was %d.",
 		    sizeof(*state), state_sz, state->size);
-	TEST_ASSERT(state->vmx.vmxon_pa == -1ull, "vmxon_pa must be -1ull.");
-	TEST_ASSERT(state->vmx.vmcs_pa == -1ull, "vmcs_pa must be -1ull.");
+	TEST_ASSERT(state->hdr.vmx.vmxon_pa == -1ull, "vmxon_pa must be -1ull.");
+	TEST_ASSERT(state->hdr.vmx.vmcs12_pa == -1ull, "vmcs_pa must be -1ull.");
 
 	free(state);
 }