Subject: [PATCH 5/7] KVM: arm/arm64: Remove the IRQ field from struct irq_phys_map

From: [email-masked] (Eric Auger)
Date: Thu, 21 Apr 2016 19:41:01 +0200

Hi Andre,
On 04/15/2016 04:04 PM, Andre Przywara wrote:
> From: Christoffer Dall <[email-masked]>
> 
> The communication of a Linux IRQ number from outside the VGIC to the
> vgic was a leftover from the day when the vgic code cared about how a
> particular device injects virtual interrupts mapped to a physical
> interrupt.
> 
> We can safely remove this notion, leaving all physical IRQ handling to
> be done in the device driver (the arch timer in this case), which makes
> room for a saner API for the new VGIC.
> 
> Signed-off-by: Christoffer Dall <[email-masked]>
> Signed-off-by: Andre Przywara <[email-masked]>
> ---
>  include/kvm/arm_vgic.h    |  3 +--
>  virt/kvm/arm/arch_timer.c | 22 ++++++++++++++++++++--
>  virt/kvm/arm/vgic.c       | 20 ++------------------
>  3 files changed, 23 insertions(+), 22 deletions(-)
> 
> diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
> index 43eeb18..49c559e 100644
> --- a/include/kvm/arm_vgic.h
> +++ b/include/kvm/arm_vgic.h
> @@ -157,7 +157,6 @@ struct vgic_io_device {
>  struct irq_phys_map {
>  	u32			virt_irq;
>  	u32			phys_irq;
> -	u32			irq;
>  };
>  
>  struct irq_phys_map_entry {
> @@ -345,7 +344,7 @@ int kvm_vgic_inject_mapped_irq(struct kvm *kvm, int cpuid,
>  void vgic_v3_dispatch_sgi(struct kvm_vcpu *vcpu, u64 reg);
>  int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu);
>  struct irq_phys_map *kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu,
> -					   int virt_irq, int irq);
> +					   int virt_irq, int phys_irq);
>  int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int virt_irq);
>  bool kvm_vgic_map_is_active(struct kvm_vcpu *vcpu, unsigned int virt_irq);
>  
> diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
> index b4d96b1..cfdf88f 100644
> --- a/virt/kvm/arm/arch_timer.c
> +++ b/virt/kvm/arm/arch_timer.c
> @@ -274,7 +274,7 @@ void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu)
>  	if (timer->active_cleared_last && !phys_active)
>  		return;
>  
> -	ret = irq_set_irqchip_state(timer->map->irq,
> +	ret = irq_set_irqchip_state(host_vtimer_irq,
>  				    IRQCHIP_STATE_ACTIVE,
>  				    phys_active);
>  	WARN_ON(ret);
> @@ -307,6 +307,9 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
>  {
>  	struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
>  	struct irq_phys_map *map;
> +	struct irq_desc *desc;
> +	struct irq_data *data;
> +	int phys_irq;
>  
>  	/*
>  	 * The vcpu timer irq number cannot be determined in
> @@ -326,10 +329,25 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
>  	kvm_timer_update_state(vcpu);
>  
>  	/*
> +	 * Find the physical IRQ number corresponding to the host_vtimer_irq
> +	 */
> +	desc = irq_to_desc(host_vtimer_irq);
> +	if (!desc) {
can this really happen?
> +		kvm_err("%s: no interrupt descriptor\n", __func__);
> +		return -EINVAL;
> +	}
> +
> +	data = irq_desc_get_irq_data(desc);
> +	while (data->parent_data)
> +		data = data->parent_data;
> +
> +	phys_irq = data->hwirq;
> +
> +	/*
>  	 * Tell the VGIC that the virtual interrupt is tied to a
>  	 * physical interrupt. We do that once per VCPU.
>  	 */
> -	map = kvm_vgic_map_phys_irq(vcpu, irq->irq, host_vtimer_irq);
> +	map = kvm_vgic_map_phys_irq(vcpu, irq->irq, phys_irq);
>  	if (WARN_ON(IS_ERR(map)))
>  		return PTR_ERR(map);
>  
> diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
> index 2d7ae35..ac5838b 100644
> --- a/virt/kvm/arm/vgic.c
> +++ b/virt/kvm/arm/vgic.c
> @@ -1723,27 +1723,13 @@ static struct list_head *vgic_get_irq_phys_map_list(struct kvm_vcpu *vcpu,
>   * Returns a valid pointer on success, and an error pointer otherwise
>   */
the doc comment must be updated
 * @irq: The Linux IRQ number

Besides

Reviewed-by: Eric Auger <[email-masked]>

Cheers

Eric

>  struct irq_phys_map *kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu,
> -					   int virt_irq, int irq)
> +					   int virt_irq, int phys_irq)
>  {
>  	struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
>  	struct list_head *root = vgic_get_irq_phys_map_list(vcpu, virt_irq);
>  	struct irq_phys_map *map;
>  	struct irq_phys_map_entry *entry;
> -	struct irq_desc *desc;
> -	struct irq_data *data;
> -	int phys_irq;
>  
> -	desc = irq_to_desc(irq);
> -	if (!desc) {
> -		kvm_err("%s: no interrupt descriptor\n", __func__);
> -		return ERR_PTR(-EINVAL);
> -	}
> -
> -	data = irq_desc_get_irq_data(desc);
> -	while (data->parent_data)
> -		data = data->parent_data;
> -
> -	phys_irq = data->hwirq;
>  
>  	/* Create a new mapping */
>  	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
> @@ -1756,8 +1742,7 @@ struct irq_phys_map *kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu,
>  	map = vgic_irq_map_search(vcpu, virt_irq);
>  	if (map) {
>  		/* Make sure this mapping matches */
> -		if (map->phys_irq != phys_irq	||
> -		    map->irq      != irq)
> +		if (map->phys_irq != phys_irq)
>  			map = ERR_PTR(-EINVAL);
>  
>  		/* Found an existing, valid mapping */
> @@ -1767,7 +1752,6 @@ struct irq_phys_map *kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu,
>  	map           = &entry->map;
>  	map->virt_irq = virt_irq;
>  	map->phys_irq = phys_irq;
> -	map->irq      = irq;
>  
>  	list_add_tail_rcu(&entry->entry, root);
>  
>