KVM/Hyper-V/VMX: Add direct tlb flush support (6f6a657c) · Commits · 戴 / test

arch/x86/include/asm/hyperv-tlfs.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -181,6 +181,7 @@
		#define HV_X64_ENLIGHTENED_VMCS_RECOMMENDED BIT(14)

		/* Nested features. These are HYPERV_CPUID_NESTED_FEATURES.EAX bits. */
		#define HV_X64_NESTED_DIRECT_FLUSH BIT(17)
		#define HV_X64_NESTED_GUEST_MAPPING_FLUSH BIT(18)
		#define HV_X64_NESTED_MSR_BITMAP BIT(19)

		@@ -892,4 +893,7 @@ struct hv_tlb_flush_ex {
		u64 gva_list[];
		} __packed;

		struct hv_partition_assist_pg {
		u32 tlb_lock_count;
		};
		#endif

arch/x86/include/asm/kvm_host.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -844,6 +844,8 @@ struct kvm_hv {

		/* How many vCPUs have VP index != vCPU index */
		atomic_t num_mismatched_vp_indexes;

		struct hv_partition_assist_pg *hv_pa_pg;
		};

		enum kvm_irqchip_mode {

arch/x86/kvm/vmx/evmcs.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -178,6 +178,8 @@ static inline void evmcs_load(u64 phys_addr)
		struct hv_vp_assist_page *vp_ap =
		hv_get_vp_assist_page(smp_processor_id());

		if (current_evmcs->hv_enlightenments_control.nested_flush_hypercall)
		vp_ap->nested_control.features.directhypercall = 1;
		vp_ap->current_nested_vmcs = phys_addr;
		vp_ap->enlighten_vmentry = 1;
		}

arch/x86/kvm/vmx/vmx.c

+39 −0

Original line number	Diff line number	Diff line
		@@ -486,6 +486,35 @@ static int hv_remote_flush_tlb(struct kvm *kvm)
		return hv_remote_flush_tlb_with_range(kvm, NULL);
		}

		static int hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu)
		{
		struct hv_enlightened_vmcs *evmcs;
		struct hv_partition_assist_pg **p_hv_pa_pg =
		&vcpu->kvm->arch.hyperv.hv_pa_pg;
		/*
		* Synthetic VM-Exit is not enabled in current code and so All
		* evmcs in singe VM shares same assist page.
		*/
		if (!*p_hv_pa_pg) {
		*p_hv_pa_pg = kzalloc(PAGE_SIZE, GFP_KERNEL);
		if (!*p_hv_pa_pg)
		return -ENOMEM;
		pr_debug("KVM: Hyper-V: allocated PA_PG for %llx\n",
		(u64)&vcpu->kvm);
		}

		evmcs = (struct hv_enlightened_vmcs *)to_vmx(vcpu)->loaded_vmcs->vmcs;

		evmcs->partition_assist_page =
		__pa(*p_hv_pa_pg);
		evmcs->hv_vm_id = (u64)vcpu->kvm;
		evmcs->hv_enlightenments_control.nested_flush_hypercall = 1;

		pr_debug("KVM: Hyper-V: enabled DIRECT flush for %llx\n",
		(u64)vcpu->kvm);
		return 0;
		}

		#endif /* IS_ENABLED(CONFIG_HYPERV) */

		/*
		@@ -6511,6 +6540,9 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu)
		current_evmcs->hv_clean_fields \|=
		HV_VMX_ENLIGHTENED_CLEAN_FIELD_ALL;

		if (static_branch_unlikely(&enable_evmcs))
		current_evmcs->hv_vp_id = vcpu->arch.hyperv.vp_index;

		/* MSR_IA32_DEBUGCTLMSR is zeroed on vmexit. Restore it if needed */
		if (vmx->host_debugctlmsr)
		update_debugctlmsr(vmx->host_debugctlmsr);
		@@ -6578,6 +6610,7 @@ static struct kvm *vmx_vm_alloc(void)

		static void vmx_vm_free(struct kvm *kvm)
		{
		kfree(kvm->arch.hyperv.hv_pa_pg);
		vfree(to_kvm_vmx(kvm));
		}

		@@ -7837,6 +7870,7 @@ static void vmx_exit(void)
		if (!vp_ap)
		continue;

		vp_ap->nested_control.features.directhypercall = 0;
		vp_ap->current_nested_vmcs = 0;
		vp_ap->enlighten_vmentry = 0;
		}
		@@ -7876,6 +7910,11 @@ static int __init vmx_init(void)
		pr_info("KVM: vmx: using Hyper-V Enlightened VMCS\n");
		static_branch_enable(&enable_evmcs);
		}

		if (ms_hyperv.nested_features & HV_X64_NESTED_DIRECT_FLUSH)
		vmx_x86_ops.enable_direct_tlbflush
		= hv_enable_direct_tlbflush;

		} else {
		enlightened_vmcs = false;
		}

Admin message