[PATCH v4 16/37] KVM: x86: hyper-v: Introduce kvm_hv_is_tlb_flush_hcall()

Vitaly Kuznetsov
2022-05-25T09:04:36Z

The newly introduced helper checks whether vCPU is performing a
Hyper-V TLB flush hypercall. This is required to filter out L2 TLB
flush hypercalls for processing.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
arch/x86/kvm/hyperv.h | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)

diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h
index aaced3768954..10c5aaa99f9f 100644
--- a/arch/x86/kvm/hyperv.h
+++ b/arch/x86/kvm/hyperv.h
@@ -171,6 +171,24 @@ static inline void kvm_hv_vcpu_empty_flush_tlb(struct kvm_vcpu *vcpu)

kfifo_reset_out(&tlb_flush_fifo->entries);
}
+
+static inline bool kvm_hv_is_tlb_flush_hcall(struct kvm_vcpu *vcpu)
+{
+ struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);
+ u16 code;
+
+ if (!hv_vcpu)
+ return false;
+
+ code = is_64_bit_hypercall(vcpu) ? kvm_rcx_read(vcpu) :
+ kvm_rax_read(vcpu);
+
+ return (code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE ||
+ code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST ||
+ code == HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX ||
+ code == HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX);
+}
+
void kvm_hv_vcpu_flush_tlb(struct kvm_vcpu *vcpu);

--
2.35.3