[PATCH 04/10] KVM: SVM: Add helper to deduplicate code for getting AVIC backing page

From: Sean Christopherson
Date: Tue Aug 15 2023 - 17:36:52 EST


Add a helper to get the physical address of the AVIC backing page, both
to deduplicate code and to prepare for getting the address directly from
apic->regs, at which point it won't be all that obvious that the address
in question is what SVM calls the AVIC backing page.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/svm/avic.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index b8313f2d88fa..954bdb45033b 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -241,14 +241,18 @@ int avic_vm_init(struct kvm *kvm)
return err;
}

+static phys_addr_t avic_get_backing_page_address(struct vcpu_svm *svm)
+{
+ return __sme_set(page_to_phys(svm->avic_backing_page));
+}
+
void avic_init_vmcb(struct vcpu_svm *svm, struct vmcb *vmcb)
{
struct kvm_svm *kvm_svm = to_kvm_svm(svm->vcpu.kvm);
- phys_addr_t bpa = __sme_set(page_to_phys(svm->avic_backing_page));
phys_addr_t lpa = __sme_set(page_to_phys(kvm_svm->avic_logical_id_table_page));
phys_addr_t ppa = __sme_set(page_to_phys(kvm_svm->avic_physical_id_table_page));

- vmcb->control.avic_backing_page = bpa;
+ vmcb->control.avic_backing_page = avic_get_backing_page_address(svm);
vmcb->control.avic_logical_id = lpa;
vmcb->control.avic_physical_id = ppa;
vmcb->control.avic_vapic_bar = APIC_DEFAULT_PHYS_BASE;
@@ -308,7 +312,7 @@ static int avic_init_backing_page(struct kvm_vcpu *vcpu)
if (!entry)
return -EINVAL;

- new_entry = __sme_set(page_to_phys(svm->avic_backing_page)) |
+ new_entry = avic_get_backing_page_address(svm) |
AVIC_PHYSICAL_ID_ENTRY_VALID_MASK;
WRITE_ONCE(*entry, new_entry);

@@ -859,7 +863,7 @@ get_pi_vcpu_info(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e,
pr_debug("SVM: %s: use GA mode for irq %u\n", __func__,
irq.vector);
*svm = to_svm(vcpu);
- vcpu_info->pi_desc_addr = __sme_set(page_to_phys((*svm)->avic_backing_page));
+ vcpu_info->pi_desc_addr = avic_get_backing_page_address(*svm);
vcpu_info->vector = irq.vector;

return 0;
@@ -917,7 +921,7 @@ int avic_pi_update_irte(struct kvm *kvm, unsigned int host_irq,
struct amd_iommu_pi_data pi;

/* Try to enable guest_mode in IRTE */
- pi.base = __sme_set(page_to_phys(svm->avic_backing_page));
+ pi.base = avic_get_backing_page_address(svm);
pi.ga_tag = AVIC_GATAG(to_kvm_svm(kvm)->avic_vm_id,
svm->vcpu.vcpu_id);
pi.is_guest_mode = true;
--
2.41.0.694.ge786442a9b-goog