[PATCH V4 15/15] KVM/VMX: Add hv tlb range flush support

[lantianyu1986@gmail.com]

From: Lan Tianyu <Tianyu.Lan@microsoft.com>

This patch is to register tlb_remote_flush_with_range callback with
hv tlb range flush interface.

Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com>
---
Change since v3:
	Merge Vitaly's don't pass EPT configuration info to
vmx_hv_remote_flush_tlb() fix.
Change since v1:
       Pass flush range with new hyper-v tlb flush struct rather
than KVM tlb flush struct.
---
 arch/x86/kvm/vmx.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 56 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 8ff13f3aed11..a93c2cc8a293 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1569,7 +1569,48 @@ static void check_ept_pointer_match(struct kvm *kvm)
 	to_kvm_vmx(kvm)->ept_pointers_match = EPT_POINTERS_MATCH;
 }
 
-static int vmx_hv_remote_flush_tlb(struct kvm *kvm)
+int kvm_parse_flush_list_func(union hv_gpa_page_range gpa_list[],
+		int offset, struct list_head *flush_list,
+		int (*fill_flush_list)(union hv_gpa_page_range gpa_list[],
+		int offset, u64 start_gfn, u64 end_gfn))
+{
+	struct kvm_mmu_page *sp;
+
+	list_for_each_entry(sp, flush_list,
+			flush_link) {
+		offset = fill_flush_list(gpa_list, offset,
+				sp->gfn, KVM_PAGES_PER_HPAGE(sp->role.level));
+	}
+
+	return offset;
+}
+
+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;
+	struct hyperv_tlb_range flush_range;
+
+	if (range) {
+		flush_range.start_gfn = range->start_gfn;
+		flush_range.pages = range->pages;
+		flush_range.flush_list = range->flush_list;
+		flush_range.parse_flush_list_func = kvm_parse_flush_list_func;
+
+		/*
+		 * FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE hypercall needs address
+		 * of the base of EPT PML4 table, strip off EPT configuration
+		 * information.
+		 */
+		return hyperv_flush_guest_mapping_range(ept_pointer & PAGE_MASK,
+				&flush_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 = -ENOTSUPP, i;
@@ -1581,16 +1622,21 @@ static int vmx_hv_remote_flush_tlb(struct kvm *kvm)
 
 	if (to_kvm_vmx(kvm)->ept_pointers_match != EPT_POINTERS_MATCH) {
 		kvm_for_each_vcpu(i, vcpu, kvm)
-			ret |= hyperv_flush_guest_mapping(
-				to_vmx(kvm_get_vcpu(kvm, i))->ept_pointer);
+			ret |= __hv_remote_flush_tlb_with_range(
+					kvm, vcpu, range);
 	} else {
-		ret = hyperv_flush_guest_mapping(
-				to_vmx(kvm_get_vcpu(kvm, 0))->ept_pointer);
+		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);
+}
 #else /* !IS_ENABLED(CONFIG_HYPERV) */
 static inline void evmcs_write64(unsigned long field, u64 value) {}
 static inline void evmcs_write32(unsigned long field, u32 value) {}
@@ -7929,8 +7975,11 @@ static __init int hardware_setup(void)
 
 #if IS_ENABLED(CONFIG_HYPERV)
 	if (ms_hyperv.nested_features & HV_X64_NESTED_GUEST_MAPPING_FLUSH
-	    && enable_ept)
-		kvm_x86_ops->tlb_remote_flush = vmx_hv_remote_flush_tlb;
+	    && enable_ept) {
+		kvm_x86_ops->tlb_remote_flush = hv_remote_flush_tlb;
+		kvm_x86_ops->tlb_remote_flush_with_range =
+				hv_remote_flush_tlb_with_range;
+	}
 #endif
 
 	if (!cpu_has_vmx_ple()) {
-- 
2.14.4