Subject: [RFC PATCH 43/45] KVM: arm/arm64: vgic-new: implement mapped IRQ handling

From: [email-masked] (Eric Auger)
Date: Fri, 1 Apr 2016 10:44:21 +0200

On 03/31/2016 08:15 PM, Christoffer Dall wrote:
> On Fri, Mar 25, 2016 at 02:05:06AM +0000, Andre Przywara wrote:
>> We now store the mapped hardware IRQ number in our struct, so we
>> don't need the irq_phys_map any longer for the new VGIC.
>> Implement the hardware IRQ mapping on top of the reworked arch
>> timer interface.
>>
>> Signed-off-by: Andre Przywara <[email-masked]>
>> ---
>>  include/kvm/vgic/vgic.h  | 15 ++++++++
>>  virt/kvm/arm/vgic/vgic.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++
>>  2 files changed, 107 insertions(+)
>>
>> diff --git a/include/kvm/vgic/vgic.h b/include/kvm/vgic/vgic.h
>> index e418de9..7c1d145 100644
>> --- a/include/kvm/vgic/vgic.h
>> +++ b/include/kvm/vgic/vgic.h
>> @@ -206,6 +206,21 @@ int kvm_vgic_hyp_init(void);
>>  
>>  int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid,
>>  			bool level);
>> +int kvm_vgic_inject_mapped_irq(struct kvm *kvm, int cpuid, unsigned int intid,
>> +			       bool level);
>> +
>> +/*
>> + * This is not really needed, but we need this type to keep the arch
>> + * timer compatible with the old VGIC implementation.
>> + * This should be removed upon retiring the old VGIC.
>> + */
>> +struct irq_phys_map {};
>> +
>> +struct irq_phys_map *kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu,
>> +					   u32 virt_irq, u32 irq);
>> +int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, struct irq_phys_map *map,
>> +			    u32 intid);
>> +bool kvm_vgic_map_is_active(struct kvm_vcpu *vcpu, u32 intid);
>>  
>>  int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu);
>>  
>> diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
>> index 4ade7c0..65395af 100644
>> --- a/virt/kvm/arm/vgic/vgic.c
>> +++ b/virt/kvm/arm/vgic/vgic.c
>> @@ -17,6 +17,9 @@
>>  #include <linux/kvm.h>
>>  #include <linux/kvm_host.h>
>>  #include <linux/list_sort.h>
>> +#include <linux/irq.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/irqdesc.h>
>>  
>>  #include "vgic.h"
>>  
>> @@ -276,6 +279,83 @@ int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid,
>>  
>>  	vcpu = kvm_get_vcpu(kvm, cpuid);
>>  	vgic_update_irq_pending(kvm, vcpu, intid, level);
>> +
>> +	return 0;
>> +}
>> +
>> +/**
>> + * kvm_vgic_inject_mapped_irq - Inject a hardware mapped IRQ to the vgic
>> + * @kvm:     The VM structure pointer
>> + * @cpuid:   The CPU for PPIs
>> + * @irq_num: The INTID to inject a new state to.
>> + * @level:   Edge-triggered:  true:  to trigger the interrupt
>> + *			      false: to ignore the call
>> + *	     Level-sensitive  true:  raise the input signal
>> + *			      false: lower the input signal
>> + *
>> + * The GIC is not concerned with devices being active-LOW or active-HIGH for
>> + * level-sensitive interrupts.  You can think of the level parameter as 1
>> + * being HIGH and 0 being LOW and all devices being active-HIGH.
>> + */
>> +int kvm_vgic_inject_mapped_irq(struct kvm *kvm, int cpuid, unsigned int intid,
>> +			       bool level)
>> +{
>> +	struct kvm_vcpu *vcpu;
>> +	int ret;
>> +
>> +	ret = vgic_lazy_init(kvm);
>> +	if (ret)
>> +		return ret;
>> +
>> +	vcpu = kvm_get_vcpu(kvm, cpuid);
>> +	vgic_update_irq_pending(kvm, vcpu, intid, level);
>> +
>> +	return 0;
>> +}
>> +
>> +struct irq_phys_map *kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu,
>> +					   u32 virt_irq, u32 intid)
>> +{
>> +	struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, virt_irq);
>> +	struct irq_desc *desc;
>> +	struct irq_data *data;
>> +
>> +	BUG_ON(!irq);
>> +
>> +	desc = irq_to_desc(intid);
> 
> eh, but that's not an INTID, that's a linux IRQ number then right?
agreed. Also the declaration suggested it is a linux irq.

Eric
> 
>> +	if (!desc) {
>> +		kvm_err("%s: no interrupt descriptor\n", __func__);
>> +		return NULL;
>> +	}
>> +
>> +	data = irq_desc_get_irq_data(desc);
>> +	while (data->parent_data)
>> +		data = data->parent_data;
>> +
>> +	spin_lock(&irq->irq_lock);
>> +
>> +	irq->hw = true;
>> +	irq->hwintid = data->hwirq;
>> +
>> +	spin_unlock(&irq->irq_lock);
>> +
>> +	return NULL;
>> +}
>> +
>> +int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, struct irq_phys_map *map,
>> +			    u32 intid)
>> +{
>> +	struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid);
>> +
>> +	BUG_ON(!irq);
>> +
>> +	spin_lock(&irq->irq_lock);
>> +
>> +	irq->hw = false;
>> +	irq->hwintid = 0;
>> +
>> +	spin_unlock(&irq->irq_lock);
>> +
>>  	return 0;
>>  }
>>  
>> @@ -520,3 +600,15 @@ int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
>>  
>>  	return pending;
>>  }
>> +
>> +bool kvm_vgic_map_is_active(struct kvm_vcpu *vcpu, u32 intid)
>> +{
>> +	struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid);
>> +	bool map_is_active;
>> +
>> +	spin_lock(&irq->irq_lock);
>> +	map_is_active = irq->hw && irq->active;
>> +	spin_unlock(&irq->irq_lock);
>> +
>> +	return map_is_active;
>> +}
>> -- 
>> 2.7.3
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe kvm" in
>> the body of a message to majordomo at vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html