KVM: arm/arm64: Enable irqchip routing

This patch adds compilation and link against irqchip.

Main motivation behind using irqchip code is to enable MSI
routing code. In the future irqchip routing may also be useful
when targeting multiple irqchips.

Routing standard callbacks now are implemented in vgic-irqfd:
- kvm_set_routing_entry
- kvm_set_irq
- kvm_set_msi

They only are supported with new_vgic code.

Both HAVE_KVM_IRQCHIP and HAVE_KVM_IRQ_ROUTING are defined.
KVM_CAP_IRQ_ROUTING is advertised and KVM_SET_GSI_ROUTING is allowed.

So from now on IRQCHIP routing is enabled and a routing table entry
must exist for irqfd injection to succeed for a given SPI. This patch
builds a default flat irqchip routing table (gsi=irqchip.pin) covering
all the VGIC SPI indexes. This routing table is overwritten by the
first first user-space call to KVM_SET_GSI_ROUTING ioctl.

MSI routing setup is not yet allowed.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

6 files changed, 44 insertions, 0 deletions

diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
index 95a000515e43..3e1cd0452d67 100644
--- a/arch/arm/kvm/Kconfig
+++ b/arch/arm/kvm/Kconfig
@@ -32,6 +32,8 @@ config KVM
 	select KVM_VFIO
 	select HAVE_KVM_EVENTFD
 	select HAVE_KVM_IRQFD
+	select HAVE_KVM_IRQCHIP
+	select HAVE_KVM_IRQ_ROUTING
 	depends on ARM_VIRT_EXT && ARM_LPAE && ARM_ARCH_TIMER
 	---help---
 	  Support hosting virtualized guest machines.
diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile
index 5e28df80dca7..10d77a66cad5 100644
--- a/arch/arm/kvm/Makefile
+++ b/arch/arm/kvm/Makefile
@@ -29,4 +29,5 @@ obj-y += $(KVM)/arm/vgic/vgic-v2.o
 obj-y += $(KVM)/arm/vgic/vgic-mmio.o
 obj-y += $(KVM)/arm/vgic/vgic-mmio-v2.o
 obj-y += $(KVM)/arm/vgic/vgic-kvm-device.o
+obj-y += $(KVM)/irqchip.o
 obj-y += $(KVM)/arm/arch_timer.o
diff --git a/arch/arm/kvm/irq.h b/arch/arm/kvm/irq.h
new file mode 100644
index 000000000000..b74099b905fd
--- /dev/null
+++ b/arch/arm/kvm/irq.h
@@ -0,0 +1,19 @@
+/*
+ * irq.h: in kernel interrupt controller related definitions
+ * Copyright (c) 2016 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This header is included by irqchip.c. However, on ARM, interrupt
+ * controller declarations are located in include/kvm/arm_vgic.h since
+ * they are mostly shared between arm and arm64.
+ */
+
+#ifndef __IRQ_H
+#define __IRQ_H
+
+#include <kvm/arm_vgic.h>
+
+#endif
diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index 9d2eff0b3ad3..9c9edc98d271 100644
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -37,6 +37,8 @@ config KVM
 	select KVM_ARM_VGIC_V3
 	select KVM_ARM_PMU if HW_PERF_EVENTS
 	select HAVE_KVM_MSI
+	select HAVE_KVM_IRQCHIP
+	select HAVE_KVM_IRQ_ROUTING
 	---help---
 	  Support hosting virtualized guest machines.
 	  We don't support KVM with 16K page tables yet, due to the multiple
diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile
index a5b96642a9cb..695eb3c7ef41 100644
--- a/arch/arm64/kvm/Makefile
+++ b/arch/arm64/kvm/Makefile
@@ -30,5 +30,6 @@ kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-mmio-v2.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-mmio-v3.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-kvm-device.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-its.o
+kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/irqchip.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/arch_timer.o
 kvm-$(CONFIG_KVM_ARM_PMU) += $(KVM)/arm/pmu.o
diff --git a/arch/arm64/kvm/irq.h b/arch/arm64/kvm/irq.h
new file mode 100644
index 000000000000..b74099b905fd
--- /dev/null
+++ b/arch/arm64/kvm/irq.h
@@ -0,0 +1,19 @@
+/*
+ * irq.h: in kernel interrupt controller related definitions
+ * Copyright (c) 2016 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This header is included by irqchip.c. However, on ARM, interrupt
+ * controller declarations are located in include/kvm/arm_vgic.h since
+ * they are mostly shared between arm and arm64.
+ */
+
+#ifndef __IRQ_H
+#define __IRQ_H
+
+#include <kvm/arm_vgic.h>
+
+#endif