[08/27] KVM: PPC: Add PV guest critical sections

Commit Message

Alexander Graf July 1, 2010, 10:42 a.m. UTC

None

Patch

diff --git a/arch/powerpc/include/asm/kvm_para.h b/arch/powerpc/include/asm/kvm_para.h
index 89c2760..d9c06ab 100644
--- a/arch/powerpc/include/asm/kvm_para.h
+++ b/arch/powerpc/include/asm/kvm_para.h
@@ -23,6 +23,7 @@ 
 #include <linux/types.h>
 
 struct kvm_vcpu_arch_shared {
+	__u64 critical;		/* Guest may not get interrupts if == r1 */
 	__u64 sprg0;
 	__u64 sprg1;
 	__u64 sprg2;
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 10afa48..ab43744 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -251,14 +251,28 @@  int kvmppc_book3s_irqprio_deliver(struct kvm_vcpu *vcpu, unsigned int priority)
 	int deliver = 1;
 	int vec = 0;
 	ulong flags = 0ULL;
+	ulong crit_raw = vcpu->arch.shared->critical;
+	ulong crit_r1 = kvmppc_get_gpr(vcpu, 1);
+	bool crit;
+
+	/* Truncate crit indicators in 32 bit mode */
+	if (!(vcpu->arch.shared->msr & MSR_SF)) {
+		crit_raw &= 0xffffffff;
+		crit_r1 &= 0xffffffff;
+	}
+
+	/* Critical section when crit == r1 */
+	crit = (crit_raw == crit_r1);
+	/* ... and we're in supervisor mode */
+	crit = crit && !(vcpu->arch.shared->msr & MSR_PR);
 
 	switch (priority) {
 	case BOOK3S_IRQPRIO_DECREMENTER:
-		deliver = vcpu->arch.shared->msr & MSR_EE;
+		deliver = (vcpu->arch.shared->msr & MSR_EE) && !crit;
 		vec = BOOK3S_INTERRUPT_DECREMENTER;
 		break;
 	case BOOK3S_IRQPRIO_EXTERNAL:
-		deliver = vcpu->arch.shared->msr & MSR_EE;
+		deliver = (vcpu->arch.shared->msr & MSR_EE) && !crit;
 		vec = BOOK3S_INTERRUPT_EXTERNAL;
 		break;
 	case BOOK3S_IRQPRIO_SYSTEM_RESET:
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index bd812f4..b9f8ecf 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -147,6 +147,20 @@  static int kvmppc_booke_irqprio_deliver(struct kvm_vcpu *vcpu,
 	int allowed = 0;
 	ulong uninitialized_var(msr_mask);
 	bool update_esr = false, update_dear = false;
+	ulong crit_raw = vcpu->arch.shared->critical;
+	ulong crit_r1 = kvmppc_get_gpr(vcpu, 1);
+	bool crit;
+
+	/* Truncate crit indicators in 32 bit mode */
+	if (!(vcpu->arch.shared->msr & MSR_SF)) {
+		crit_raw &= 0xffffffff;
+		crit_r1 &= 0xffffffff;
+	}
+
+	/* Critical section when crit == r1 */
+	crit = (crit_raw == crit_r1);
+	/* ... and we're in supervisor mode */
+	crit = crit && !(vcpu->arch.shared->msr & MSR_PR);
 
 	switch (priority) {
 	case BOOKE_IRQPRIO_DTLB_MISS:
@@ -181,6 +195,7 @@  static int kvmppc_booke_irqprio_deliver(struct kvm_vcpu *vcpu,
 	case BOOKE_IRQPRIO_DECREMENTER:
 	case BOOKE_IRQPRIO_FIT:
 		allowed = vcpu->arch.shared->msr & MSR_EE;
+		allowed = allowed && !crit;
 		msr_mask = MSR_CE|MSR_ME|MSR_DE;
 		break;
 	case BOOKE_IRQPRIO_DEBUG: