KVM: PPC: Support eventfd

In order to support the generic eventfd infrastructure on PPC, we need
to call into the generic KVM in-kernel device mmio code.
Signed-off-by: Alexander Graf <agraf@suse.de>

arch/powerpc/kvm/Kconfig

@@ -20,6 +20,7 @@ config KVM
 	bool
 	select PREEMPT_NOTIFIERS
 	select ANON_INODES
+	select HAVE_KVM_EVENTFD
 
 config KVM_BOOK3S_HANDLER
 	bool

arch/powerpc/kvm/Makefile

@@ -6,7 +6,8 @@ subdir-ccflags-$(CONFIG_PPC_WERROR) := -Werror
 
 ccflags-y := -Ivirt/kvm -Iarch/powerpc/kvm
 
-common-objs-y = $(addprefix ../../../virt/kvm/, kvm_main.o coalesced_mmio.o)
+common-objs-y = $(addprefix ../../../virt/kvm/, kvm_main.o coalesced_mmio.o \
+						eventfd.o)
 
 CFLAGS_44x_tlb.o  := -I.
 CFLAGS_e500_tlb.o := -I.
@@ -76,6 +77,7 @@ kvm-book3s_64-builtin-objs-$(CONFIG_KVM_BOOK3S_64_HV) := \
 
 kvm-book3s_64-module-objs := \
 	../../../virt/kvm/kvm_main.o \
+	../../../virt/kvm/eventfd.o \
 	powerpc.o \
 	emulate.o \
 	book3s.o \

arch/powerpc/kvm/powerpc.c

@@ -314,6 +314,7 @@ int kvm_dev_ioctl_check_extension(long ext)
 	case KVM_CAP_PPC_IRQ_LEVEL:
 	case KVM_CAP_ENABLE_CAP:
 	case KVM_CAP_ONE_REG:
+	case KVM_CAP_IOEVENTFD:
 		r = 1;
 		break;
 #ifndef CONFIG_KVM_BOOK3S_64_HV
@@ -618,6 +619,13 @@ int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
 	vcpu->mmio_is_write = 0;
 	vcpu->arch.mmio_sign_extend = 0;
 
+	if (!kvm_io_bus_read(vcpu->kvm, KVM_MMIO_BUS, run->mmio.phys_addr,
+			     bytes, &run->mmio.data)) {
+		kvmppc_complete_mmio_load(vcpu, run);
+		vcpu->mmio_needed = 0;
+		return EMULATE_DONE;
+	}
+
 	return EMULATE_DO_MMIO;
 }
 
@@ -627,8 +635,8 @@ int kvmppc_handle_loads(struct kvm_run *run, struct kvm_vcpu *vcpu,
 {
 	int r;
 
-	r = kvmppc_handle_load(run, vcpu, rt, bytes, is_bigendian);
 	vcpu->arch.mmio_sign_extend = 1;
+	r = kvmppc_handle_load(run, vcpu, rt, bytes, is_bigendian);
 
 	return r;
 }
@@ -666,6 +674,13 @@ int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
 		}
 	}
 
+	if (!kvm_io_bus_write(vcpu->kvm, KVM_MMIO_BUS, run->mmio.phys_addr,
+			      bytes, &run->mmio.data)) {
+		kvmppc_complete_mmio_load(vcpu, run);
+		vcpu->mmio_needed = 0;
+		return EMULATE_DONE;
+	}
+
 	return EMULATE_DO_MMIO;
 }