[04/21] KVM: PPC: Teach MMIO Signedness

Commit Message

Alexander Graf Feb. 19, 2010, 10 a.m. UTC

None

Patch

diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index fb87dcf..119deb4 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -270,6 +270,7 @@  struct kvm_vcpu_arch {
 
 	u8 io_gpr; /* GPR used as IO source/target */
 	u8 mmio_is_bigendian;
+	u8 mmio_sign_extend;
 	u8 dcr_needed;
 	u8 dcr_is_write;
 
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index c011170..a288dd2 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -48,6 +48,9 @@  extern void kvmppc_dump_vcpu(struct kvm_vcpu *vcpu);
 extern int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
                               unsigned int rt, unsigned int bytes,
                               int is_bigendian);
+extern int kvmppc_handle_loads(struct kvm_run *run, struct kvm_vcpu *vcpu,
+                               unsigned int rt, unsigned int bytes,
+                               int is_bigendian);
 extern int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
                                u64 val, unsigned int bytes, int is_bigendian);
 
diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c
index cb72a65..11789dd 100644
--- a/arch/powerpc/kvm/emulate.c
+++ b/arch/powerpc/kvm/emulate.c
@@ -62,6 +62,8 @@ 
 #define OP_STBU 39
 #define OP_LHZ  40
 #define OP_LHZU 41
+#define OP_LHA  42
+#define OP_LHAU 43
 #define OP_STH  44
 #define OP_STHU 45
 
@@ -450,6 +452,18 @@  int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu)
 		kvmppc_set_gpr(vcpu, ra, vcpu->arch.paddr_accessed);
 		break;
 
+	case OP_LHA:
+		rt = get_rt(inst);
+		emulated = kvmppc_handle_loads(run, vcpu, rt, 2, 1);
+		break;
+
+	case OP_LHAU:
+		ra = get_ra(inst);
+		rt = get_rt(inst);
+		emulated = kvmppc_handle_loads(run, vcpu, rt, 2, 1);
+		kvmppc_set_gpr(vcpu, ra, vcpu->arch.paddr_accessed);
+		break;
+
 	case OP_STH:
 		rs = get_rs(inst);
 		emulated = kvmppc_handle_store(run, vcpu,
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 14b431e..a1f9626 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -300,6 +300,22 @@  static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu,
 		}
 	}
 
+	if (vcpu->arch.mmio_sign_extend) {
+		switch (run->mmio.len) {
+#ifdef CONFIG_PPC64
+		case 4:
+			gpr = (s64)(s32)gpr;
+			break;
+#endif
+		case 2:
+			gpr = (s64)(s16)gpr;
+			break;
+		case 1:
+			gpr = (s64)(s8)gpr;
+			break;
+		}
+	}
+
 	kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, gpr);
 
 	switch (vcpu->arch.io_gpr & KVM_REG_EXT_MASK) {
@@ -337,10 +353,23 @@  int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
 	vcpu->arch.mmio_is_bigendian = is_bigendian;
 	vcpu->mmio_needed = 1;
 	vcpu->mmio_is_write = 0;
+	vcpu->arch.mmio_sign_extend = 0;
 
 	return EMULATE_DO_MMIO;
 }
 
+/* Same as above, but sign extends */
+int kvmppc_handle_loads(struct kvm_run *run, struct kvm_vcpu *vcpu,
+                        unsigned int rt, unsigned int bytes, int is_bigendian)
+{
+	int r;
+
+	r = kvmppc_handle_load(run, vcpu, rt, bytes, is_bigendian);
+	vcpu->arch.mmio_sign_extend = 1;
+
+	return r;
+}
+
 int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
                         u64 val, unsigned int bytes, int is_bigendian)
 {