[PATCH v12 23/84] KVM: nVMX: Add helper to put (unmap) vmcs12 pages

Sean Christopherson
2024-07-27T00:02:25Z

Add a helper to dedup unmapping the vmcs12 pages. This will reduce the
amount of churn when a future patch refactors the kvm_vcpu_unmap() API.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/vmx/nested.c | 32 ++++++++++++++++++--------------
1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 372d005e09e7..8d05d1d9f544 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -314,6 +314,21 @@ static void vmx_switch_vmcs(struct kvm_vcpu *vcpu, struct loaded_vmcs *vmcs)
vcpu->arch.regs_dirty = 0;
}

+static void nested_put_vmcs12_pages(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+ /*
+ * Unpin physical memory we referred to in the vmcs02. The APIC access
+ * page's backing page (yeah, confusing) shouldn't actually be accessed,
+ * and if it is written, the contents are irrelevant.
+ */
+ kvm_vcpu_unmap(vcpu, &vmx->nested.apic_access_page_map, false);
+ kvm_vcpu_unmap(vcpu, &vmx->nested.virtual_apic_map, true);
+ kvm_vcpu_unmap(vcpu, &vmx->nested.pi_desc_map, true);
+ vmx->nested.pi_desc = NULL;
+}
+
/*
* Free whatever needs to be freed from vmx->nested when L1 goes down, or
* just stops using VMX.
@@ -346,15 +361,8 @@ static void free_nested(struct kvm_vcpu *vcpu)
vmx->nested.cached_vmcs12 = NULL;
kfree(vmx->nested.cached_shadow_vmcs12);
vmx->nested.cached_shadow_vmcs12 = NULL;
- /*
- * Unpin physical memory we referred to in the vmcs02. The APIC access
- * page's backing page (yeah, confusing) shouldn't actually be accessed,
- * and if it is written, the contents are irrelevant.
- */
- kvm_vcpu_unmap(vcpu, &vmx->nested.apic_access_page_map, false);
- kvm_vcpu_unmap(vcpu, &vmx->nested.virtual_apic_map, true);
- kvm_vcpu_unmap(vcpu, &vmx->nested.pi_desc_map, true);
- vmx->nested.pi_desc = NULL;
+
+ nested_put_vmcs12_pages(vcpu);

kvm_mmu_free_roots(vcpu->kvm, &vcpu->arch.guest_mmu, KVM_MMU_ROOTS_ALL);

@@ -4942,11 +4950,7 @@ void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 vm_exit_reason,
vmx_update_cpu_dirty_logging(vcpu);
}

- /* Unpin physical memory we referred to in vmcs02 */
- kvm_vcpu_unmap(vcpu, &vmx->nested.apic_access_page_map, false);
- kvm_vcpu_unmap(vcpu, &vmx->nested.virtual_apic_map, true);
- kvm_vcpu_unmap(vcpu, &vmx->nested.pi_desc_map, true);
- vmx->nested.pi_desc = NULL;
+ nested_put_vmcs12_pages(vcpu);

if (vmx->nested.reload_vmcs01_apic_access_page) {
vmx->nested.reload_vmcs01_apic_access_page = false;