intc/arm_gic: Support IRQ injection for more than 256 vpus

Host kernels that expose the KVM_CAP_ARM_IRQ_LINE_LAYOUT_2 capability
allow injection of interrupts along with vcpu ids larger than 255.
Let's encode the vpcu id on 12 bits according to the upgraded KVM_IRQ_LINE
ABI when needed.

Given that we have two callsites that need to assemble
the value for kvm_set_irq(), a new helper routine, kvm_arm_set_irq
is introduced.

Without that patch qemu exits with "kvm_set_irq: Invalid argument"
message.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reported-by: Zenghui Yu <yuzenghui@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Message-id: 20191003154640.22451-3-eric.auger@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
diff --git a/hw/intc/arm_gic_kvm.c b/hw/intc/arm_gic_kvm.c
index b56fda1..9deb15e 100644
--- a/hw/intc/arm_gic_kvm.c
+++ b/hw/intc/arm_gic_kvm.c
@@ -55,7 +55,7 @@
      * has separate fields in the irq number for type,
      * CPU number and interrupt number.
      */
-    int kvm_irq, irqtype, cpu;
+    int irqtype, cpu;
 
     if (irq < (num_irq - GIC_INTERNAL)) {
         /* External interrupt. The kernel numbers these like the GIC
@@ -72,10 +72,7 @@
         cpu = irq / GIC_INTERNAL;
         irq %= GIC_INTERNAL;
     }
-    kvm_irq = (irqtype << KVM_ARM_IRQ_TYPE_SHIFT)
-        | (cpu << KVM_ARM_IRQ_VCPU_SHIFT) | irq;
-
-    kvm_set_irq(kvm_state, kvm_irq, !!level);
+    kvm_arm_set_irq(cpu, irqtype, irq, !!level);
 }
 
 static void kvm_arm_gicv2_set_irq(void *opaque, int irq, int level)