KVM: x86: Mark GPRs dirty when written

When performing VMGEXIT processing for an SEV-ES guest, register values
will be synced between KVM and the GHCB. Prepare for detecting when a GPR
has been updated (marked dirty) in order to determine whether to sync the
register to the GHCB.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <7ca2a1cdb61456f2fe9c64193e34d601e395c133.1607620209.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/kvm_cache_regs.h

@@ -9,34 +9,6 @@
 	(X86_CR4_PVI | X86_CR4_DE | X86_CR4_PCE | X86_CR4_OSFXSR  \
 	 | X86_CR4_OSXMMEXCPT | X86_CR4_PGE | X86_CR4_TSD | X86_CR4_FSGSBASE)
 
-#define BUILD_KVM_GPR_ACCESSORS(lname, uname)				      \
-static __always_inline unsigned long kvm_##lname##_read(struct kvm_vcpu *vcpu)\
-{									      \
-	return vcpu->arch.regs[VCPU_REGS_##uname];			      \
-}									      \
-static __always_inline void kvm_##lname##_write(struct kvm_vcpu *vcpu,	      \
-						unsigned long val)	      \
-{									      \
-	vcpu->arch.regs[VCPU_REGS_##uname] = val;			      \
-}
-BUILD_KVM_GPR_ACCESSORS(rax, RAX)
-BUILD_KVM_GPR_ACCESSORS(rbx, RBX)
-BUILD_KVM_GPR_ACCESSORS(rcx, RCX)
-BUILD_KVM_GPR_ACCESSORS(rdx, RDX)
-BUILD_KVM_GPR_ACCESSORS(rbp, RBP)
-BUILD_KVM_GPR_ACCESSORS(rsi, RSI)
-BUILD_KVM_GPR_ACCESSORS(rdi, RDI)
-#ifdef CONFIG_X86_64
-BUILD_KVM_GPR_ACCESSORS(r8,  R8)
-BUILD_KVM_GPR_ACCESSORS(r9,  R9)
-BUILD_KVM_GPR_ACCESSORS(r10, R10)
-BUILD_KVM_GPR_ACCESSORS(r11, R11)
-BUILD_KVM_GPR_ACCESSORS(r12, R12)
-BUILD_KVM_GPR_ACCESSORS(r13, R13)
-BUILD_KVM_GPR_ACCESSORS(r14, R14)
-BUILD_KVM_GPR_ACCESSORS(r15, R15)
-#endif
-
 static inline bool kvm_register_is_available(struct kvm_vcpu *vcpu,
 					     enum kvm_reg reg)
 {
@@ -62,6 +34,35 @@ static inline void kvm_register_mark_dirty(struct kvm_vcpu *vcpu,
 	__set_bit(reg, (unsigned long *)&vcpu->arch.regs_dirty);
 }
 
+#define BUILD_KVM_GPR_ACCESSORS(lname, uname)				      \
+static __always_inline unsigned long kvm_##lname##_read(struct kvm_vcpu *vcpu)\
+{									      \
+	return vcpu->arch.regs[VCPU_REGS_##uname];			      \
+}									      \
+static __always_inline void kvm_##lname##_write(struct kvm_vcpu *vcpu,	      \
+						unsigned long val)	      \
+{									      \
+	vcpu->arch.regs[VCPU_REGS_##uname] = val;			      \
+	kvm_register_mark_dirty(vcpu, VCPU_REGS_##uname);		      \
+}
+BUILD_KVM_GPR_ACCESSORS(rax, RAX)
+BUILD_KVM_GPR_ACCESSORS(rbx, RBX)
+BUILD_KVM_GPR_ACCESSORS(rcx, RCX)
+BUILD_KVM_GPR_ACCESSORS(rdx, RDX)
+BUILD_KVM_GPR_ACCESSORS(rbp, RBP)
+BUILD_KVM_GPR_ACCESSORS(rsi, RSI)
+BUILD_KVM_GPR_ACCESSORS(rdi, RDI)
+#ifdef CONFIG_X86_64
+BUILD_KVM_GPR_ACCESSORS(r8,  R8)
+BUILD_KVM_GPR_ACCESSORS(r9,  R9)
+BUILD_KVM_GPR_ACCESSORS(r10, R10)
+BUILD_KVM_GPR_ACCESSORS(r11, R11)
+BUILD_KVM_GPR_ACCESSORS(r12, R12)
+BUILD_KVM_GPR_ACCESSORS(r13, R13)
+BUILD_KVM_GPR_ACCESSORS(r14, R14)
+BUILD_KVM_GPR_ACCESSORS(r15, R15)
+#endif
+
 static inline unsigned long kvm_register_read(struct kvm_vcpu *vcpu, int reg)
 {
 	if (WARN_ON_ONCE((unsigned int)reg >= NR_VCPU_REGS))