[PATCH v2 2/8] KVM: arm64: Make vcpu_{read,write}_sys_reg available to HYP code

[Fuad Tabba]

The vcpu_{read,write}_sys_reg() accessors are host-only, so helpers
built on them such as kvm_vcpu_set_be()/kvm_vcpu_is_be() cannot be
shared with hyp code. exception.c already wraps them in
__vcpu_{read,write}_sys_reg(), which pick the host- or hyp-side accessor
via has_vhe() and so are valid in any context.

Move those wrappers to kvm_emulate.h as kvm_vcpu_{read,write}_sys_reg()
and switch the callers over, so a follow-up series can share that
emulation code at EL2.

No functional change intended.

Signed-off-by: Fuad Tabba <tabba at google.com>
---
 arch/arm64/include/asm/kvm_emulate.h | 22 +++++++++++++++---
 arch/arm64/kvm/hyp/exception.c       | 34 ++++++++--------------------
 2 files changed, 28 insertions(+), 28 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index 5bf3d7e1d92c..80b30fead3d1 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -506,6 +506,22 @@ static inline unsigned long kvm_vcpu_get_mpidr_aff(struct kvm_vcpu *vcpu)
 	return __vcpu_sys_reg(vcpu, MPIDR_EL1) & MPIDR_HWID_BITMASK;
 }
 
+static inline u64 kvm_vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg)
+{
+	if (has_vhe())
+		return vcpu_read_sys_reg(vcpu, reg);
+
+	return __vcpu_sys_reg(vcpu, reg);
+}
+
+static inline void kvm_vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg)
+{
+	if (has_vhe())
+		vcpu_write_sys_reg(vcpu, val, reg);
+	else
+		__vcpu_assign_sys_reg(vcpu, reg, val);
+}
+
 static inline void kvm_vcpu_set_be(struct kvm_vcpu *vcpu)
 {
 	if (vcpu_mode_is_32bit(vcpu)) {
@@ -516,9 +532,9 @@ static inline void kvm_vcpu_set_be(struct kvm_vcpu *vcpu)
 
 		r = vcpu_has_nv(vcpu) ? SCTLR_EL2 : SCTLR_EL1;
 
-		sctlr = vcpu_read_sys_reg(vcpu, r);
+		sctlr = kvm_vcpu_read_sys_reg(vcpu, r);
 		sctlr |= SCTLR_ELx_EE;
-		vcpu_write_sys_reg(vcpu, sctlr, r);
+		kvm_vcpu_write_sys_reg(vcpu, sctlr, r);
 	}
 }
 
@@ -533,7 +549,7 @@ static inline bool kvm_vcpu_is_be(struct kvm_vcpu *vcpu)
 	r = is_hyp_ctxt(vcpu) ? SCTLR_EL2 : SCTLR_EL1;
 	bit = vcpu_mode_priv(vcpu) ? SCTLR_ELx_EE : SCTLR_EL1_E0E;
 
-	return vcpu_read_sys_reg(vcpu, r) & bit;
+	return kvm_vcpu_read_sys_reg(vcpu, r) & bit;
 }
 
 static inline unsigned long vcpu_data_guest_to_host(struct kvm_vcpu *vcpu,
diff --git a/arch/arm64/kvm/hyp/exception.c b/arch/arm64/kvm/hyp/exception.c
index bef40ddb16db..2cb68dc7d441 100644
--- a/arch/arm64/kvm/hyp/exception.c
+++ b/arch/arm64/kvm/hyp/exception.c
@@ -20,22 +20,6 @@
 #error Hypervisor code only!
 #endif
 
-static inline u64 __vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg)
-{
-	if (has_vhe())
-		return vcpu_read_sys_reg(vcpu, reg);
-
-	return __vcpu_sys_reg(vcpu, reg);
-}
-
-static inline void __vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg)
-{
-	if (has_vhe())
-		vcpu_write_sys_reg(vcpu, val, reg);
-	else
-		__vcpu_assign_sys_reg(vcpu, reg, val);
-}
-
 static void __vcpu_write_spsr(struct kvm_vcpu *vcpu, unsigned long target_mode,
 			      u64 val)
 {
@@ -101,14 +85,14 @@ static void enter_exception64(struct kvm_vcpu *vcpu, unsigned long target_mode,
 
 	switch (target_mode) {
 	case PSR_MODE_EL1h:
-		vbar = __vcpu_read_sys_reg(vcpu, VBAR_EL1);
-		sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL1);
-		__vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL1);
+		vbar = kvm_vcpu_read_sys_reg(vcpu, VBAR_EL1);
+		sctlr = kvm_vcpu_read_sys_reg(vcpu, SCTLR_EL1);
+		kvm_vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL1);
 		break;
 	case PSR_MODE_EL2h:
-		vbar = __vcpu_read_sys_reg(vcpu, VBAR_EL2);
-		sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL2);
-		__vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL2);
+		vbar = kvm_vcpu_read_sys_reg(vcpu, VBAR_EL2);
+		sctlr = kvm_vcpu_read_sys_reg(vcpu, SCTLR_EL2);
+		kvm_vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL2);
 		break;
 	default:
 		/* Don't do that */
@@ -185,7 +169,7 @@ static void enter_exception64(struct kvm_vcpu *vcpu, unsigned long target_mode,
  */
 static unsigned long get_except32_cpsr(struct kvm_vcpu *vcpu, u32 mode)
 {
-	u32 sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL1);
+	u32 sctlr = kvm_vcpu_read_sys_reg(vcpu, SCTLR_EL1);
 	unsigned long old, new;
 
 	old = *vcpu_cpsr(vcpu);
@@ -281,7 +265,7 @@ static void enter_exception32(struct kvm_vcpu *vcpu, u32 mode, u32 vect_offset)
 {
 	unsigned long spsr = *vcpu_cpsr(vcpu);
 	bool is_thumb = (spsr & PSR_AA32_T_BIT);
-	u32 sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL1);
+	u32 sctlr = kvm_vcpu_read_sys_reg(vcpu, SCTLR_EL1);
 	u32 return_address;
 
 	*vcpu_cpsr(vcpu) = get_except32_cpsr(vcpu, mode);
@@ -305,7 +289,7 @@ static void enter_exception32(struct kvm_vcpu *vcpu, u32 mode, u32 vect_offset)
 	if (sctlr & (1 << 13))
 		vect_offset += 0xffff0000;
 	else /* always have security exceptions */
-		vect_offset += __vcpu_read_sys_reg(vcpu, VBAR_EL1);
+		vect_offset += kvm_vcpu_read_sys_reg(vcpu, VBAR_EL1);
 
 	*vcpu_pc(vcpu) = vect_offset;
 }
-- 
2.55.0.rc0.738.g0c8ab3ebcc-goog