Add EVENTFD support for KVM/MIPS, which is needed by VHOST. Tested on
Loongson-3 platform.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
---
 arch/mips/kvm/Kconfig     | 1 +
 arch/mips/kvm/Makefile    | 2 +-
 arch/mips/kvm/trap_emul.c | 3 +++
 arch/mips/kvm/vz.c        | 3 +++
 4 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
index eac25ae..80b0464 100644
--- a/arch/mips/kvm/Kconfig
+++ b/arch/mips/kvm/Kconfig
@@ -22,6 +22,7 @@ config KVM
 	select EXPORT_UASM
 	select PREEMPT_NOTIFIERS
 	select KVM_GENERIC_DIRTYLOG_READ_PROTECT
+	select HAVE_KVM_EVENTFD
 	select HAVE_KVM_VCPU_ASYNC_IOCTL
 	select KVM_MMIO
 	select MMU_NOTIFIER
diff --git a/arch/mips/kvm/Makefile b/arch/mips/kvm/Makefile
index 01affc1..0a3cef6 100644
--- a/arch/mips/kvm/Makefile
+++ b/arch/mips/kvm/Makefile
@@ -2,7 +2,7 @@
 # Makefile for KVM support for MIPS
 #
 
-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)
 
 EXTRA_CFLAGS += -Ivirt/kvm -Iarch/mips/kvm
 
diff --git a/arch/mips/kvm/trap_emul.c b/arch/mips/kvm/trap_emul.c
index 5a11e83..f464506b 100644
--- a/arch/mips/kvm/trap_emul.c
+++ b/arch/mips/kvm/trap_emul.c
@@ -529,6 +529,9 @@ static int kvm_trap_emul_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_MIPS_TE:
 		r = 1;
 		break;
+	case KVM_CAP_IOEVENTFD:
+		r = 1;
+		break;
 	default:
 		r = 0;
 		break;
diff --git a/arch/mips/kvm/vz.c b/arch/mips/kvm/vz.c
index dde2088..17932ab 100644
--- a/arch/mips/kvm/vz.c
+++ b/arch/mips/kvm/vz.c
@@ -2927,6 +2927,9 @@ static int kvm_vz_check_extension(struct kvm *kvm, long ext)
 		r = 2;
 		break;
 #endif
+	case KVM_CAP_IOEVENTFD:
+		r = 1;
+		break;
 	default:
 		r = 0;
 		break;
-- 
2.7.0