KVM: MTRR: clean up mtrr default type

Drop kvm_mtrr->enable, omit the decode/code workload and get rid of
all the hard code

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/include/asm/kvm_host.h

@@ -345,8 +345,7 @@ enum {
 struct kvm_mtrr {
 	struct mtrr_var_range var_ranges[KVM_NR_VAR_MTRR];
 	mtrr_type fixed_ranges[KVM_NR_FIXED_MTRR_REGION];
-	unsigned char enabled;
-	mtrr_type def_type;
+	u64 deftype;
 };
 
 struct kvm_vcpu_arch {

arch/x86/kvm/mtrr.c

@@ -22,6 +22,10 @@
 #include "cpuid.h"
 #include "mmu.h"
 
+#define IA32_MTRR_DEF_TYPE_E		(1ULL << 11)
+#define IA32_MTRR_DEF_TYPE_FE		(1ULL << 10)
+#define IA32_MTRR_DEF_TYPE_TYPE_MASK	(0xff)
+
 static bool msr_mtrr_valid(unsigned msr)
 {
 	switch (msr) {
@@ -101,10 +105,24 @@ bool kvm_mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 }
 EXPORT_SYMBOL_GPL(kvm_mtrr_valid);
 
+static bool mtrr_is_enabled(struct kvm_mtrr *mtrr_state)
+{
+	return !!(mtrr_state->deftype & IA32_MTRR_DEF_TYPE_E);
+}
+
+static bool fixed_mtrr_is_enabled(struct kvm_mtrr *mtrr_state)
+{
+	return !!(mtrr_state->deftype & IA32_MTRR_DEF_TYPE_FE);
+}
+
+static u8 mtrr_default_type(struct kvm_mtrr *mtrr_state)
+{
+	return mtrr_state->deftype & IA32_MTRR_DEF_TYPE_TYPE_MASK;
+}
+
 static void update_mtrr(struct kvm_vcpu *vcpu, u32 msr)
 {
 	struct kvm_mtrr *mtrr_state = &vcpu->arch.mtrr_state;
-	unsigned char mtrr_enabled = mtrr_state->enabled;
 	gfn_t start, end, mask;
 	int index;
 	bool is_fixed = true;
@@ -113,7 +131,7 @@ static void update_mtrr(struct kvm_vcpu *vcpu, u32 msr)
 	      !kvm_arch_has_noncoherent_dma(vcpu->kvm))
 		return;
 
-	if (!(mtrr_enabled & 0x2) && msr != MSR_MTRRdefType)
+	if (!mtrr_is_enabled(mtrr_state) && msr != MSR_MTRRdefType)
 		return;
 
 	switch (msr) {
@@ -152,7 +170,7 @@ static void update_mtrr(struct kvm_vcpu *vcpu, u32 msr)
 		end = ((start & mask) | ~mask) + 1;
 	}
 
-	if (is_fixed && !(mtrr_enabled & 0x1))
+	if (is_fixed && !fixed_mtrr_is_enabled(mtrr_state))
 		return;
 
 	kvm_zap_gfn_range(vcpu->kvm, gpa_to_gfn(start), gpa_to_gfn(end));
@@ -165,10 +183,9 @@ int kvm_mtrr_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 	if (!kvm_mtrr_valid(vcpu, msr, data))
 		return 1;
 
-	if (msr == MSR_MTRRdefType) {
-		vcpu->arch.mtrr_state.def_type = data;
-		vcpu->arch.mtrr_state.enabled = (data & 0xc00) >> 10;
-	} else if (msr == MSR_MTRRfix64K_00000)
+	if (msr == MSR_MTRRdefType)
+		vcpu->arch.mtrr_state.deftype = data;
+	else if (msr == MSR_MTRRfix64K_00000)
 		p[0] = data;
 	else if (msr == MSR_MTRRfix16K_80000 || msr == MSR_MTRRfix16K_A0000)
 		p[1 + msr - MSR_MTRRfix16K_80000] = data;
@@ -215,8 +232,7 @@ int kvm_mtrr_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
 		return 1;
 
 	if (msr == MSR_MTRRdefType)
-		*pdata = vcpu->arch.mtrr_state.def_type +
-			 (vcpu->arch.mtrr_state.enabled << 10);
+		*pdata = vcpu->arch.mtrr_state.deftype;
 	else if (msr == MSR_MTRRfix64K_00000)
 		*pdata = p[0];
 	else if (msr == MSR_MTRRfix16K_80000 || msr == MSR_MTRRfix16K_A0000)
@@ -255,14 +271,14 @@ static int get_mtrr_type(struct kvm_mtrr *mtrr_state,
 	int i, num_var_ranges = KVM_NR_VAR_MTRR;
 
 	/* MTRR is completely disabled, use UC for all of physical memory. */
-	if (!(mtrr_state->enabled & 0x2))
+	if (!mtrr_is_enabled(mtrr_state))
 		return MTRR_TYPE_UNCACHABLE;
 
 	/* Make end inclusive end, instead of exclusive */
 	end--;
 
 	/* Look in fixed ranges. Just return the type as per start */
-	if ((mtrr_state->enabled & 0x1) && (start < 0x100000)) {
+	if (fixed_mtrr_is_enabled(mtrr_state) && (start < 0x100000)) {
 		int idx;
 
 		if (start < 0x80000) {
@@ -330,7 +346,7 @@ static int get_mtrr_type(struct kvm_mtrr *mtrr_state,
 	if (prev_match != 0xFF)
 		return prev_match;
 
-	return mtrr_state->def_type;
+	return mtrr_default_type(mtrr_state);
 }
 
 u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn)