[PATCH 1/4] KVM: x86: Add helpers to check bit set in CR0/CR4 and return in bool

[Binbin Wu <binbin.wu@linux.intel.com>]

Add helps kvm_is_cr0_bit_set()/kvm_is_cr4_bit_set() to check if one
specific bit is set or not in CR0/CR4 of vCPU and return the result
in bool.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com>
---
 arch/x86/kvm/kvm_cache_regs.h | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/arch/x86/kvm/kvm_cache_regs.h b/arch/x86/kvm/kvm_cache_regs.h
index 4c91f626c058..f2bf930a3cd4 100644
--- a/arch/x86/kvm/kvm_cache_regs.h
+++ b/arch/x86/kvm/kvm_cache_regs.h
@@ -157,6 +157,14 @@ static inline ulong kvm_read_cr0_bits(struct kvm_vcpu *vcpu, ulong mask)
 	return vcpu->arch.cr0 & mask;
 }
 
+static __always_inline bool kvm_is_cr0_bit_set(struct kvm_vcpu *vcpu,
+					       unsigned long cr0_bit)
+{
+	BUILD_BUG_ON(!is_power_of_2(cr0_bit));
+
+	return !!kvm_read_cr0_bits(vcpu, cr0_bit);
+}
+
 static inline ulong kvm_read_cr0(struct kvm_vcpu *vcpu)
 {
 	return kvm_read_cr0_bits(vcpu, ~0UL);
@@ -171,6 +179,14 @@ static inline ulong kvm_read_cr4_bits(struct kvm_vcpu *vcpu, ulong mask)
 	return vcpu->arch.cr4 & mask;
 }
 
+static __always_inline bool kvm_is_cr4_bit_set(struct kvm_vcpu *vcpu,
+					       unsigned long cr4_bit)
+{
+	BUILD_BUG_ON(!is_power_of_2(cr4_bit));
+
+	return !!kvm_read_cr4_bits(vcpu, cr4_bit);
+}
+
 static inline ulong kvm_read_cr3(struct kvm_vcpu *vcpu)
 {
 	if (!kvm_register_is_available(vcpu, VCPU_EXREG_CR3))
-- 
2.25.1