KVM: VMX: Add a helper function to retrieve the GPR index for INVPCID, INVVPID, and...

handle_invept(), handle_invvpid(), handle_invpcid() read the same reg2
field in vmcs.VMX_INSTRUCTION_INFO to get the index of the GPR that
holds the invalidation type. Add a helper to retrieve reg2 from VMX
instruction info to consolidate and document the shift+mask magic.

Signed-off-by: Vipin Sharma <vipinsh@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211109174426.2350547-2-vipinsh@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 341c508..b213ca9 100644 (file)
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -5343,7 +5343,7 @@ static int handle_invept(struct kvm_vcpu *vcpu)
        struct {
                u64 eptp, gpa;
        } operand;
-       int i, r;
+       int i, r, gpr_index;
 
        if (!(vmx->nested.msrs.secondary_ctls_high &
              SECONDARY_EXEC_ENABLE_EPT) ||
@@ -5356,7 +5356,8 @@ static int handle_invept(struct kvm_vcpu *vcpu)
                return 1;
 
        vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
-       type = kvm_register_read(vcpu, (vmx_instruction_info >> 28) & 0xf);
+       gpr_index = vmx_get_instr_info_reg2(vmx_instruction_info);
+       type = kvm_register_read(vcpu, gpr_index);
 
        types = (vmx->nested.msrs.ept_caps >> VMX_EPT_EXTENT_SHIFT) & 6;
 
@@ -5423,7 +5424,7 @@ static int handle_invvpid(struct kvm_vcpu *vcpu)
                u64 gla;
        } operand;
        u16 vpid02;
-       int r;
+       int r, gpr_index;
 
        if (!(vmx->nested.msrs.secondary_ctls_high &
              SECONDARY_EXEC_ENABLE_VPID) ||
@@ -5436,7 +5437,8 @@ static int handle_invvpid(struct kvm_vcpu *vcpu)
                return 1;
 
        vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
-       type = kvm_register_read(vcpu, (vmx_instruction_info >> 28) & 0xf);
+       gpr_index = vmx_get_instr_info_reg2(vmx_instruction_info);
+       type = kvm_register_read(vcpu, gpr_index);
 
        types = (vmx->nested.msrs.vpid_caps &
                        VMX_VPID_EXTENT_SUPPORTED_MASK) >> 8;

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 160c308..2abcbbb 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -5443,6 +5443,7 @@ static int handle_invpcid(struct kvm_vcpu *vcpu)
                u64 pcid;
                u64 gla;
        } operand;
+       int gpr_index;
 
        if (!guest_cpuid_has(vcpu, X86_FEATURE_INVPCID)) {
                kvm_queue_exception(vcpu, UD_VECTOR);
@@ -5450,7 +5451,8 @@ static int handle_invpcid(struct kvm_vcpu *vcpu)
        }
 
        vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
-       type = kvm_register_read(vcpu, (vmx_instruction_info >> 28) & 0xf);
+       gpr_index = vmx_get_instr_info_reg2(vmx_instruction_info);
+       type = kvm_register_read(vcpu, gpr_index);
 
        if (type > 3) {
                kvm_inject_gp(vcpu, 0);

diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 86c093d..a4ead60 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -550,4 +550,9 @@ static inline bool vmx_guest_state_valid(struct kvm_vcpu *vcpu)
 
 void dump_vmcs(struct kvm_vcpu *vcpu);
 
+static inline int vmx_get_instr_info_reg2(u32 vmx_instr_info)
+{
+       return (vmx_instr_info >> 28) & 0xf;
+}
+
 #endif /* __KVM_X86_VMX_H */