[PATCH v1 24/28] KVM: x86/mmu: Refactor kvm_mmu_invlpg() to allow skipping the GVA flush

[Yosry Ahmed]

Refactor helpers out of kvm_mmu_invalidate_addr() and kvm_mmu_invlpg()
that take in an extra argument to skip the GVA flush.

This will be used when invalidating GVAs in a different context than the
current one (i.e.  invalidating an L2 GVA from L1), so flushing the
current context would flush the wrong TLB entries.

No functional change intended.

Signed-off-by: Yosry Ahmed <yosry@xxxxxxxxxx>
---
 arch/x86/kvm/mmu/mmu.c | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 1889413759d2e..0d3e3b351b31c 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -6664,8 +6664,8 @@ static void kvm_mmu_sync_addr(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
 	write_unlock(&vcpu->kvm->mmu_lock);
 }
 
-void kvm_mmu_invalidate_addr(struct kvm_vcpu *vcpu, struct kvm_pagewalk *w,
-			     u64 addr, unsigned long roots)
+static void __kvm_mmu_invalidate_addr(struct kvm_vcpu *vcpu, struct kvm_pagewalk *w,
+				      u64 addr, unsigned long roots, bool flush_gva)
 {
 	struct kvm_mmu *mmu;
 	int i;
@@ -6678,7 +6678,8 @@ void kvm_mmu_invalidate_addr(struct kvm_vcpu *vcpu, struct kvm_pagewalk *w,
 		if (is_noncanonical_invlpg_address(addr, vcpu))
 			return;
 
-		kvm_x86_call(flush_tlb_gva)(vcpu, addr);
+		if (flush_gva)
+			kvm_x86_call(flush_tlb_gva)(vcpu, addr);
 
 		if (tdp_enabled)
 			return;
@@ -6700,9 +6701,15 @@ void kvm_mmu_invalidate_addr(struct kvm_vcpu *vcpu, struct kvm_pagewalk *w,
 			kvm_mmu_sync_addr(vcpu, mmu, addr, mmu->prev_roots[i].hpa);
 	}
 }
+
+void kvm_mmu_invalidate_addr(struct kvm_vcpu *vcpu, struct kvm_pagewalk *w,
+			     u64 addr, unsigned long roots)
+{
+	__kvm_mmu_invalidate_addr(vcpu, w, addr, roots, true);
+}
 EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_mmu_invalidate_addr);
 
-void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva)
+static void __kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva, bool flush_gva)
 {
 	/*
 	 * INVLPG is required to invalidate any global mappings for the VA,
@@ -6714,11 +6721,16 @@ void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva)
 	 * be synced when switching to that new cr3, so nothing needs to be
 	 * done here for them.
 	 */
-	kvm_mmu_invalidate_addr(vcpu, &vcpu->arch.gva_walk, gva, KVM_MMU_ROOTS_ALL);
+	__kvm_mmu_invalidate_addr(vcpu, &vcpu->arch.gva_walk, gva,
+				  KVM_MMU_ROOTS_ALL, flush_gva);
 	++vcpu->stat.invlpg;
 }
-EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_mmu_invlpg);
 
+void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva)
+{
+	__kvm_mmu_invlpg(vcpu, gva, true);
+}
+EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_mmu_invlpg);
 
 void kvm_mmu_invpcid_gva(struct kvm_vcpu *vcpu, gva_t gva, unsigned long pcid)
 {
-- 
2.55.0.229.g6434b31f56-goog