On 03/12/12 13:25, Will Deacon wrote:

On Sat, Nov 10, 2012 at 03:45:18PM +0000, Christoffer Dall wrote:

quoted

From: Marc Zyngier <redacted>

Plug the interrupt injection code. Interrupts can now be generated
from user space.

Signed-off-by: Marc Zyngier <redacted>
Signed-off-by: Christoffer Dall <redacted>
---
 arch/arm/include/asm/kvm_vgic.h |    8 +++
 arch/arm/kvm/arm.c              |   29 +++++++++++++
 arch/arm/kvm/vgic.c             |   90 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 127 insertions(+)

diff --git a/arch/arm/include/asm/kvm_vgic.h b/arch/arm/include/asm/kvm_vgic.h
index 7229324..6e3d303 100644
--- a/arch/arm/include/asm/kvm_vgic.h
+++ b/arch/arm/include/asm/kvm_vgic.h

@@ -241,6 +241,8 @@ struct kvm_exit_mmio;
 int kvm_vgic_set_addr(struct kvm *kvm, unsigned long type, u64 addr);
 void kvm_vgic_sync_to_cpu(struct kvm_vcpu *vcpu);
 void kvm_vgic_sync_from_cpu(struct kvm_vcpu *vcpu);
+int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num,
+			bool level);
 int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu);
 bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run,
 		      struct kvm_exit_mmio *mmio);

@@ -271,6 +273,12 @@ static inline void kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu) {}
 static inline void kvm_vgic_sync_to_cpu(struct kvm_vcpu *vcpu) {}
 static inline void kvm_vgic_sync_from_cpu(struct kvm_vcpu *vcpu) {}
 
+static inline int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid,
+				      const struct kvm_irq_level *irq)
+{
+	return 0;
+}
+
 static inline int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
 {
 	return 0;

diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 3ac1aab..f43da01 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c

@@ -764,10 +764,31 @@ int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level)
 
 	switch (irq_type) {
 	case KVM_ARM_IRQ_TYPE_CPU:
+		if (irqchip_in_kernel(kvm))
+			return -ENXIO;
+
 		if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
 			return -EINVAL;
 
 		return vcpu_interrupt_line(vcpu, irq_num, level);
+#ifdef CONFIG_KVM_ARM_VGIC
+	case KVM_ARM_IRQ_TYPE_PPI:
+		if (!irqchip_in_kernel(kvm))
+			return -ENXIO;
+
+		if (irq_num < 16 || irq_num > 31)
+			return -EINVAL;

It's our favourite two numbers again! :)

I already fixed a number of them. Probably missed this one though.

quoted

+
+		return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level);
+	case KVM_ARM_IRQ_TYPE_SPI:
+		if (!irqchip_in_kernel(kvm))
+			return -ENXIO;
+
+		if (irq_num < 32 || irq_num > KVM_ARM_IRQ_GIC_MAX)
+			return -EINVAL;
+
+		return kvm_vgic_inject_irq(kvm, 0, irq_num, level);
+#endif
 	}
 
 	return -EINVAL;

@@ -849,6 +870,14 @@ long kvm_arch_vm_ioctl(struct file *filp,
 	void __user *argp = (void __user *)arg;
 
 	switch (ioctl) {
+#ifdef CONFIG_KVM_ARM_VGIC
+	case KVM_CREATE_IRQCHIP: {
+		if (vgic_present)
+			return kvm_vgic_create(kvm);
+		else
+			return -EINVAL;

ENXIO? At least, that's what you use when setting the GIC addresses.

-EINVAL seems to be one of the values other archs are using. -ENXIO is
not one of them for KVM_CREATE_IRQCHIP. Doesn't mean they are right, but
for the sake of keeping userspace happy, I'm not really inclined to
change this.

Christoffer?

quoted

+	}
+#endif
 	case KVM_SET_DEVICE_ADDRESS: {
 		struct kvm_device_address dev_addr;
 

diff --git a/arch/arm/kvm/vgic.c b/arch/arm/kvm/vgic.c
index dda5623..70040bb 100644
--- a/arch/arm/kvm/vgic.c
+++ b/arch/arm/kvm/vgic.c

@@ -75,6 +75,7 @@
 #define ACCESS_WRITE_MASK(x)	((x) & (3 << 1))
 
 static void vgic_update_state(struct kvm *kvm);
+static void vgic_kick_vcpus(struct kvm *kvm);
 static void vgic_dispatch_sgi(struct kvm_vcpu *vcpu, u32 reg);
 
 static inline int vgic_irq_is_edge(struct vgic_dist *dist, int irq)

@@ -542,6 +543,9 @@ bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run, struct kvm_exi
 	kvm_prepare_mmio(run, mmio);
 	kvm_handle_mmio_return(vcpu, run);
 
+	if (updated_state)
+		vgic_kick_vcpus(vcpu->kvm);
+
 	return true;
 }
 

@@ -867,6 +871,92 @@ int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
 	return test_bit(vcpu->vcpu_id, &dist->irq_pending_on_cpu);
 }
 
+static void vgic_kick_vcpus(struct kvm *kvm)
+{
+	struct kvm_vcpu *vcpu;
+	int c;
+
+	/*
+	 * We've injected an interrupt, time to find out who deserves
+	 * a good kick...
+	 */
+	kvm_for_each_vcpu(c, vcpu, kvm) {
+		if (kvm_vgic_vcpu_pending_irq(vcpu))
+			kvm_vcpu_kick(vcpu);
+	}
+}
+
+static bool vgic_update_irq_state(struct kvm *kvm, int cpuid,
+				  unsigned int irq_num, bool level)
+{
+	struct vgic_dist *dist = &kvm->arch.vgic;
+	struct kvm_vcpu *vcpu;
+	int is_edge, is_level, state;
+	int enabled;
+	bool ret = true;
+
+	spin_lock(&dist->lock);
+
+	is_edge = vgic_irq_is_edge(dist, irq_num);
+	is_level = !is_edge;
+	state = vgic_bitmap_get_irq_val(&dist->irq_state, cpuid, irq_num);
+
+	/*
+	 * Only inject an interrupt if:
+	 * - level triggered and we change level
+	 * - edge triggered and we have a rising edge
+	 */
+	if ((is_level && !(state ^ level)) || (is_edge && (state || !level))) {
+		ret = false;
+		goto out;
+	}

Eek, more of the edge/level combo. Can this be be restructured so that we
have vgic_update_{edge,level}_irq_state, which are called from here
appropriately?

I'll have a look.

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...