[PATCH 3/7] KVM: x86: hyper-v: Move the remote TLB flush logic out of vmx

[Vineeth Pillai <viremana@linux.microsoft.com>]

Currently the remote TLB flush logic is specific to VMX.
Move it to a common place so that SVM can use it as well.

Signed-off-by: Vineeth Pillai <viremana@linux.microsoft.com>
---
 arch/x86/include/asm/kvm_host.h | 15 +++++
 arch/x86/kvm/hyperv.c           | 89 ++++++++++++++++++++++++++++++
 arch/x86/kvm/hyperv.h           | 12 ++++
 arch/x86/kvm/vmx/vmx.c          | 97 +++------------------------------
 arch/x86/kvm/vmx/vmx.h          | 10 ----
 5 files changed, 123 insertions(+), 100 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 877a4025d8da..336716124b7e 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -530,6 +530,12 @@ struct kvm_vcpu_hv {
 	struct kvm_vcpu_hv_stimer stimer[HV_SYNIC_STIMER_COUNT];
 	DECLARE_BITMAP(stimer_pending_bitmap, HV_SYNIC_STIMER_COUNT);
 	cpumask_t tlb_flush;
+	/*
+	 * Two Dimensional paging CR3
+	 * EPTP for Intel
+	 * nCR3 for AMD
+	 */
+	u64 tdp_pointer;
 };
 
 /* Xen HVM per vcpu emulation context */
@@ -884,6 +890,12 @@ struct kvm_hv_syndbg {
 	u64 options;
 };
 
+enum tdp_pointers_status {
+	TDP_POINTERS_CHECK = 0,
+	TDP_POINTERS_MATCH = 1,
+	TDP_POINTERS_MISMATCH = 2
+};
+
 /* Hyper-V emulation context */
 struct kvm_hv {
 	struct mutex hv_lock;
@@ -908,6 +920,9 @@ struct kvm_hv {
 
 	struct hv_partition_assist_pg *hv_pa_pg;
 	struct kvm_hv_syndbg hv_syndbg;
+
+	enum tdp_pointers_status tdp_pointers_match;
+	spinlock_t tdp_pointer_lock;
 };
 
 struct msr_bitmap_range {
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 58fa8c029867..c5bec598bf28 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -32,6 +32,7 @@
 #include <linux/eventfd.h>
 
 #include <asm/apicdef.h>
+#include <asm/mshyperv.h>
 #include <trace/events/kvm.h>
 
 #include "trace.h"
@@ -913,6 +914,8 @@ static int kvm_hv_vcpu_init(struct kvm_vcpu *vcpu)
 	for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
 		stimer_init(&hv_vcpu->stimer[i], i);
 
+	hv_vcpu->tdp_pointer = INVALID_PAGE;
+
 	hv_vcpu->vp_index = kvm_vcpu_get_idx(vcpu);
 
 	return 0;
@@ -1960,6 +1963,7 @@ void kvm_hv_init_vm(struct kvm *kvm)
 {
 	struct kvm_hv *hv = to_kvm_hv(kvm);
 
+	spin_lock_init(&hv->tdp_pointer_lock);
 	mutex_init(&hv->hv_lock);
 	idr_init(&hv->conn_to_evt);
 }
@@ -2180,3 +2184,88 @@ int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
 
 	return 0;
 }
+
+/* check_tdp_pointer() should be under protection of tdp_pointer_lock. */
+static void check_tdp_pointer_match(struct kvm *kvm)
+{
+	u64 tdp_pointer = INVALID_PAGE;
+	bool valid_tdp = false;
+	struct kvm_vcpu *vcpu;
+	int i;
+
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		if (!valid_tdp) {
+			tdp_pointer = to_hv_vcpu(vcpu)->tdp_pointer;
+			valid_tdp = true;
+			continue;
+		}
+
+		if (tdp_pointer != to_hv_vcpu(vcpu)->tdp_pointer) {
+			to_kvm_hv(kvm)->tdp_pointers_match
+				= TDP_POINTERS_MISMATCH;
+			return;
+		}
+	}
+
+	to_kvm_hv(kvm)->tdp_pointers_match = TDP_POINTERS_MATCH;
+}
+
+static int kvm_fill_hv_flush_list_func(struct hv_guest_mapping_flush_list *flush,
+		void *data)
+{
+	struct kvm_tlb_range *range = data;
+
+	return hyperv_fill_flush_guest_mapping_list(flush, range->start_gfn,
+			range->pages);
+}
+
+static inline int __hv_remote_flush_tlb_with_range(struct kvm *kvm,
+		struct kvm_vcpu *vcpu, struct kvm_tlb_range *range)
+{
+	u64 tdp_pointer = to_hv_vcpu(vcpu)->tdp_pointer;
+
+	/*
+	 * FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE hypercall needs address
+	 * of the base of EPT PML4 table, strip off EPT configuration
+	 * information.
+	 */
+	if (range)
+		return hyperv_flush_guest_mapping_range(tdp_pointer & PAGE_MASK,
+				kvm_fill_hv_flush_list_func, (void *)range);
+	else
+		return hyperv_flush_guest_mapping(tdp_pointer & PAGE_MASK);
+}
+
+int kvm_hv_remote_flush_tlb_with_range(struct kvm *kvm,
+		struct kvm_tlb_range *range)
+{
+	struct kvm_vcpu *vcpu;
+	int ret = 0, i;
+
+	spin_lock(&to_kvm_hv(kvm)->tdp_pointer_lock);
+
+	if (to_kvm_hv(kvm)->tdp_pointers_match == TDP_POINTERS_CHECK)
+		check_tdp_pointer_match(kvm);
+
+	if (to_kvm_hv(kvm)->tdp_pointers_match != TDP_POINTERS_MATCH) {
+		kvm_for_each_vcpu(i, vcpu, kvm) {
+			/* If tdp_pointer is invalid pointer, bypass flush request. */
+			if (VALID_PAGE(to_hv_vcpu(vcpu)->tdp_pointer))
+				ret |= __hv_remote_flush_tlb_with_range(
+					kvm, vcpu, range);
+		}
+	} else {
+		ret = __hv_remote_flush_tlb_with_range(kvm,
+				kvm_get_vcpu(kvm, 0), range);
+	}
+
+	spin_unlock(&to_kvm_hv(kvm)->tdp_pointer_lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(kvm_hv_remote_flush_tlb_with_range);
+
+int kvm_hv_remote_flush_tlb(struct kvm *kvm)
+{
+	return kvm_hv_remote_flush_tlb_with_range(kvm, NULL);
+}
+EXPORT_SYMBOL_GPL(kvm_hv_remote_flush_tlb);
diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
index e951af1fcb2c..225ede22a815 100644
--- a/arch/x86/kvm/hyperv.h
+++ b/arch/x86/kvm/hyperv.h
@@ -141,4 +141,16 @@ int kvm_vm_ioctl_hv_eventfd(struct kvm *kvm, struct kvm_hyperv_eventfd *args);
 int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
 		     struct kvm_cpuid_entry2 __user *entries);
 
+static inline void kvm_update_arch_tdp_pointer(struct kvm *kvm,
+		struct kvm_vcpu *vcpu, u64 tdp_pointer)
+{
+	spin_lock(&to_kvm_hv(kvm)->tdp_pointer_lock);
+	to_hv_vcpu(vcpu)->tdp_pointer = tdp_pointer;
+	to_kvm_hv(kvm)->tdp_pointers_match = TDP_POINTERS_CHECK;
+	spin_unlock(&to_kvm_hv(kvm)->tdp_pointer_lock);
+}
+
+int kvm_hv_remote_flush_tlb(struct kvm *kvm);
+int kvm_hv_remote_flush_tlb_with_range(struct kvm *kvm,
+		struct kvm_tlb_range *range);
 #endif
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 50810d471462..67f607319eb7 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -62,6 +62,7 @@
 #include "vmcs12.h"
 #include "vmx.h"
 #include "x86.h"
+#include "hyperv.h"
 
 MODULE_AUTHOR("Qumranet");
 MODULE_LICENSE("GPL");
@@ -472,83 +473,6 @@ static const u32 vmx_uret_msrs_list[] = {
 static bool __read_mostly enlightened_vmcs = true;
 module_param(enlightened_vmcs, bool, 0444);
 
-/* check_ept_pointer() should be under protection of ept_pointer_lock. */
-static void check_ept_pointer_match(struct kvm *kvm)
-{
-	struct kvm_vcpu *vcpu;
-	u64 tmp_eptp = INVALID_PAGE;
-	int i;
-
-	kvm_for_each_vcpu(i, vcpu, kvm) {
-		if (!VALID_PAGE(tmp_eptp)) {
-			tmp_eptp = to_vmx(vcpu)->ept_pointer;
-		} else if (tmp_eptp != to_vmx(vcpu)->ept_pointer) {
-			to_kvm_vmx(kvm)->ept_pointers_match
-				= EPT_POINTERS_MISMATCH;
-			return;
-		}
-	}
-
-	to_kvm_vmx(kvm)->ept_pointers_match = EPT_POINTERS_MATCH;
-}
-
-static int kvm_fill_hv_flush_list_func(struct hv_guest_mapping_flush_list *flush,
-		void *data)
-{
-	struct kvm_tlb_range *range = data;
-
-	return hyperv_fill_flush_guest_mapping_list(flush, range->start_gfn,
-			range->pages);
-}
-
-static inline int __hv_remote_flush_tlb_with_range(struct kvm *kvm,
-		struct kvm_vcpu *vcpu, struct kvm_tlb_range *range)
-{
-	u64 ept_pointer = to_vmx(vcpu)->ept_pointer;
-
-	/*
-	 * FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE hypercall needs address
-	 * of the base of EPT PML4 table, strip off EPT configuration
-	 * information.
-	 */
-	if (range)
-		return hyperv_flush_guest_mapping_range(ept_pointer & PAGE_MASK,
-				kvm_fill_hv_flush_list_func, (void *)range);
-	else
-		return hyperv_flush_guest_mapping(ept_pointer & PAGE_MASK);
-}
-
-static int hv_remote_flush_tlb_with_range(struct kvm *kvm,
-		struct kvm_tlb_range *range)
-{
-	struct kvm_vcpu *vcpu;
-	int ret = 0, i;
-
-	spin_lock(&to_kvm_vmx(kvm)->ept_pointer_lock);
-
-	if (to_kvm_vmx(kvm)->ept_pointers_match == EPT_POINTERS_CHECK)
-		check_ept_pointer_match(kvm);
-
-	if (to_kvm_vmx(kvm)->ept_pointers_match != EPT_POINTERS_MATCH) {
-		kvm_for_each_vcpu(i, vcpu, kvm) {
-			/* If ept_pointer is invalid pointer, bypass flush request. */
-			if (VALID_PAGE(to_vmx(vcpu)->ept_pointer))
-				ret |= __hv_remote_flush_tlb_with_range(
-					kvm, vcpu, range);
-		}
-	} else {
-		ret = __hv_remote_flush_tlb_with_range(kvm,
-				kvm_get_vcpu(kvm, 0), range);
-	}
-
-	spin_unlock(&to_kvm_vmx(kvm)->ept_pointer_lock);
-	return ret;
-}
-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;
@@ -3115,13 +3039,10 @@ static void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, unsigned long pgd,
 		eptp = construct_eptp(vcpu, pgd, pgd_level);
 		vmcs_write64(EPT_POINTER, eptp);
 
-		if (kvm_x86_ops.tlb_remote_flush) {
-			spin_lock(&to_kvm_vmx(kvm)->ept_pointer_lock);
-			to_vmx(vcpu)->ept_pointer = eptp;
-			to_kvm_vmx(kvm)->ept_pointers_match
-				= EPT_POINTERS_CHECK;
-			spin_unlock(&to_kvm_vmx(kvm)->ept_pointer_lock);
-		}
+#if IS_ENABLED(CONFIG_HYPERV)
+		if (kvm_x86_ops.tlb_remote_flush)
+			kvm_update_arch_tdp_pointer(kvm, vcpu, eptp);
+#endif
 
 		if (!enable_unrestricted_guest && !is_paging(vcpu))
 			guest_cr3 = to_kvm_vmx(kvm)->ept_identity_map_addr;
@@ -6989,8 +6910,6 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu)
 	vmx->pi_desc.nv = POSTED_INTR_VECTOR;
 	vmx->pi_desc.sn = 1;
 
-	vmx->ept_pointer = INVALID_PAGE;
-
 	return 0;
 
 free_vmcs:
@@ -7007,8 +6926,6 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu)
 
 static int vmx_vm_init(struct kvm *kvm)
 {
-	spin_lock_init(&to_kvm_vmx(kvm)->ept_pointer_lock);
-
 	if (!ple_gap)
 		kvm->arch.pause_in_guest = true;
 
@@ -7818,9 +7735,9 @@ static __init int hardware_setup(void)
 #if IS_ENABLED(CONFIG_HYPERV)
 	if (ms_hyperv.nested_features & HV_X64_NESTED_GUEST_MAPPING_FLUSH
 	    && enable_ept) {
-		vmx_x86_ops.tlb_remote_flush = hv_remote_flush_tlb;
+		vmx_x86_ops.tlb_remote_flush = kvm_hv_remote_flush_tlb;
 		vmx_x86_ops.tlb_remote_flush_with_range =
-				hv_remote_flush_tlb_with_range;
+				kvm_hv_remote_flush_tlb_with_range;
 	}
 #endif
 
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 89da5e1251f1..d2e2ab46f5bb 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -325,7 +325,6 @@ struct vcpu_vmx {
 	 */
 	u64 msr_ia32_feature_control;
 	u64 msr_ia32_feature_control_valid_bits;
-	u64 ept_pointer;
 
 	struct pt_desc pt_desc;
 	struct lbr_desc lbr_desc;
@@ -338,21 +337,12 @@ struct vcpu_vmx {
 	} shadow_msr_intercept;
 };
 
-enum ept_pointers_status {
-	EPT_POINTERS_CHECK = 0,
-	EPT_POINTERS_MATCH = 1,
-	EPT_POINTERS_MISMATCH = 2
-};
-
 struct kvm_vmx {
 	struct kvm kvm;
 
 	unsigned int tss_addr;
 	bool ept_identity_pagetable_done;
 	gpa_t ept_identity_map_addr;
-
-	enum ept_pointers_status ept_pointers_match;
-	spinlock_t ept_pointer_lock;
 };
 
 bool nested_vmx_allowed(struct kvm_vcpu *vcpu);
-- 
2.25.1