KVM: arm/arm64: Unify 32bit fault injection

Both arm and arm64 implementations are capable of injecting
faults, and yet have completely divergent implementations,
leading to different bugs and reduced maintainability.

Let's elect the arm64 version as the canonical one
and move it into aarch32.c, which is common to both
architectures.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

2 files changed, 6 insertions, 71 deletions

diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index e5df3fce0008..bf61da0ef82b 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -41,6 +41,9 @@ void kvm_inject_undefined(struct kvm_vcpu *vcpu);
 void kvm_inject_vabt(struct kvm_vcpu *vcpu);
 void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr);
 void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr);
+void kvm_inject_undef32(struct kvm_vcpu *vcpu);
+void kvm_inject_dabt32(struct kvm_vcpu *vcpu, unsigned long addr);
+void kvm_inject_pabt32(struct kvm_vcpu *vcpu, unsigned long addr);
 
 static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu)
 {
diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c
index da6a8cfa54a0..8ecbcb40e317 100644
--- a/arch/arm64/kvm/inject_fault.c
+++ b/arch/arm64/kvm/inject_fault.c
@@ -33,74 +33,6 @@
 #define LOWER_EL_AArch64_VECTOR		0x400
 #define LOWER_EL_AArch32_VECTOR		0x600
 
-static void prepare_fault32(struct kvm_vcpu *vcpu, u32 mode, u32 vect_offset)
-{
-	unsigned long cpsr;
-	unsigned long new_spsr_value = *vcpu_cpsr(vcpu);
-	bool is_thumb = (new_spsr_value & COMPAT_PSR_T_BIT);
-	u32 return_offset = (is_thumb) ? 4 : 0;
-	u32 sctlr = vcpu_cp15(vcpu, c1_SCTLR);
-
-	cpsr = mode | COMPAT_PSR_I_BIT;
-
-	if (sctlr & (1 << 30))
-		cpsr |= COMPAT_PSR_T_BIT;
-	if (sctlr & (1 << 25))
-		cpsr |= COMPAT_PSR_E_BIT;
-
-	*vcpu_cpsr(vcpu) = cpsr;
-
-	/* Note: These now point to the banked copies */
-	*vcpu_spsr(vcpu) = new_spsr_value;
-	*vcpu_reg32(vcpu, 14) = *vcpu_pc(vcpu) + return_offset;
-
-	/* Branch to exception vector */
-	if (sctlr & (1 << 13))
-		vect_offset += 0xffff0000;
-	else /* always have security exceptions */
-		vect_offset += vcpu_cp15(vcpu, c12_VBAR);
-
-	*vcpu_pc(vcpu) = vect_offset;
-}
-
-static void inject_undef32(struct kvm_vcpu *vcpu)
-{
-	prepare_fault32(vcpu, COMPAT_PSR_MODE_UND, 4);
-}
-
-/*
- * Modelled after TakeDataAbortException() and TakePrefetchAbortException
- * pseudocode.
- */
-static void inject_abt32(struct kvm_vcpu *vcpu, bool is_pabt,
-			 unsigned long addr)
-{
-	u32 vect_offset;
-	u32 *far, *fsr;
-	bool is_lpae;
-
-	if (is_pabt) {
-		vect_offset = 12;
-		far = &vcpu_cp15(vcpu, c6_IFAR);
-		fsr = &vcpu_cp15(vcpu, c5_IFSR);
-	} else { /* !iabt */
-		vect_offset = 16;
-		far = &vcpu_cp15(vcpu, c6_DFAR);
-		fsr = &vcpu_cp15(vcpu, c5_DFSR);
-	}
-
-	prepare_fault32(vcpu, COMPAT_PSR_MODE_ABT | COMPAT_PSR_A_BIT, vect_offset);
-
-	*far = addr;
-
-	/* Give the guest an IMPLEMENTATION DEFINED exception */
-	is_lpae = (vcpu_cp15(vcpu, c2_TTBCR) >> 31);
-	if (is_lpae)
-		*fsr = 1 << 9 | 0x34;
-	else
-		*fsr = 0x14;
-}
-
 enum exception_type {
 	except_type_sync	= 0,
 	except_type_irq		= 0x80,
@@ -197,7 +129,7 @@ static void inject_undef64(struct kvm_vcpu *vcpu)
 void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr)
 {
 	if (!(vcpu->arch.hcr_el2 & HCR_RW))
-		inject_abt32(vcpu, false, addr);
+		kvm_inject_dabt32(vcpu, addr);
 	else
 		inject_abt64(vcpu, false, addr);
 }
@@ -213,7 +145,7 @@ void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr)
 void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr)
 {
 	if (!(vcpu->arch.hcr_el2 & HCR_RW))
-		inject_abt32(vcpu, true, addr);
+		kvm_inject_pabt32(vcpu, addr);
 	else
 		inject_abt64(vcpu, true, addr);
 }
@@ -227,7 +159,7 @@ void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr)
 void kvm_inject_undefined(struct kvm_vcpu *vcpu)
 {
 	if (!(vcpu->arch.hcr_el2 & HCR_RW))
-		inject_undef32(vcpu);
+		kvm_inject_undef32(vcpu);
 	else
 		inject_undef64(vcpu);
 }