On Wed, Apr 10, 2024 at 03:07:32PM -0700, isaku.yamahata@xxxxxxxxx wrote:
>From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
>
>Wire KVM_MAP_MEMORY ioctl to kvm_mmu_map_tdp_page() to populate guest
>memory. When KVM_CREATE_VCPU creates vCPU, it initializes the x86
>KVM MMU part by kvm_mmu_create() and kvm_init_mmu(). vCPU is ready to
>invoke the KVM page fault handler.
>
>Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
>---
>v2:
>- Catch up the change of struct kvm_memory_mapping. (Sean)
>- Removed mapping level check. Push it down into vendor code. (David, Sean)
>- Rename goal_level to level. (Sean)
>- Drop kvm_arch_pre_vcpu_map_memory(), directly call kvm_mmu_reload().
> (David, Sean)
>- Fixed the update of mapping.
>---
> arch/x86/kvm/x86.c | 30 ++++++++++++++++++++++++++++++
> 1 file changed, 30 insertions(+)
>
>diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
>index 2d2619d3eee4..2c765de3531e 100644
>--- a/arch/x86/kvm/x86.c
>+++ b/arch/x86/kvm/x86.c
>@@ -4713,6 +4713,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
> case KVM_CAP_VM_DISABLE_NX_HUGE_PAGES:
> case KVM_CAP_IRQFD_RESAMPLE:
> case KVM_CAP_MEMORY_FAULT_INFO:
>+ case KVM_CAP_MAP_MEMORY:
> r = 1;
> break;
> case KVM_CAP_EXIT_HYPERCALL:
>@@ -5867,6 +5868,35 @@ static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
> }
> }
>
>+int kvm_arch_vcpu_map_memory(struct kvm_vcpu *vcpu,
>+ struct kvm_memory_mapping *mapping)
>+{
>+ u64 end, error_code = 0;
>+ u8 level = PG_LEVEL_4K;
IIUC, no need to initialize @level here.
>+ int r;
>+
>+ /*
>+ * Shadow paging uses GVA for kvm page fault. The first implementation
>+ * supports GPA only to avoid confusion.
>+ */
>+ if (!tdp_enabled)
>+ return -EOPNOTSUPP;
This check duplicates the one for vcpu->arch.mmu->page_fault() in patch 5.
>+
>+ /* reload is optimized for repeated call. */
>+ kvm_mmu_reload(vcpu);
>+
>+ r = kvm_tdp_map_page(vcpu, mapping->base_address, error_code, &level);
>+ if (r)
>+ return r;
>+
>+ /* mapping->base_address is not necessarily aligned to level-hugepage. */
>+ end = (mapping->base_address & KVM_HPAGE_MASK(level)) +
>+ KVM_HPAGE_SIZE(level);
maybe
end = ALIGN(mapping->base_address, KVM_HPAGE_SIZE(level));
>+ mapping->size -= end - mapping->base_address;
>+ mapping->base_address = end;
>+ return r;
>+}
>+
> long kvm_arch_vcpu_ioctl(struct file *filp,
> unsigned int ioctl, unsigned long arg)
> {
>--
>2.43.2
>
>
