Re: [RFC PATCH 22/45] KVM: arm/arm64: vgic-new: Add SGIPENDR register handlers

Christoffer Dall
2016-03-31T11:37:58Z

On Fri, Mar 25, 2016 at 02:04:45AM +0000, Andre Przywara wrote:
> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
>
> ---
> virt/kvm/arm/vgic/vgic_mmio.c | 79 ++++++++++++++++++++++++++++++++-----------
> 1 file changed, 59 insertions(+), 20 deletions(-)
>
> diff --git a/virt/kvm/arm/vgic/vgic_mmio.c b/virt/kvm/arm/vgic/vgic_mmio.c
> index a49726f..2ab8961 100644
> --- a/virt/kvm/arm/vgic/vgic_mmio.c
> +++ b/virt/kvm/arm/vgic/vgic_mmio.c
> @@ -64,24 +64,6 @@ int vgic_mmio_write_wi(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
> return 0;
> }
>
> -static int vgic_mmio_read_nyi(struct kvm_vcpu *vcpu,
> - struct kvm_io_device *this,
> - gpa_t addr, int len, void *val)
> -{
> - pr_warn("KVM: handling unimplemented VGIC MMIO read: VCPU %d, address: 0x%llx\n",
> - vcpu->vcpu_id, (unsigned long long)addr);
> - return 0;
> -}
> -
> -static int vgic_mmio_write_nyi(struct kvm_vcpu *vcpu,
> - struct kvm_io_device *this,
> - gpa_t addr, int len, const void *val)
> -{
> - pr_warn("KVM: handling unimplemented VGIC MMIO write: VCPU %d, address: 0x%llx\n",
> - vcpu->vcpu_id, (unsigned long long)addr);
> - return 0;
> -}
> -
> static int vgic_mmio_read_v2_misc(struct kvm_vcpu *vcpu,
> struct kvm_io_device *this,
> gpa_t addr, int len, void *val)
> @@ -556,6 +538,63 @@ static int vgic_mmio_write_sgir(struct kvm_vcpu *source_vcpu,
> return 0;
> }
>
> +static int vgic_mmio_read_sgipend(struct kvm_vcpu *vcpu,
> + struct kvm_io_device *this,
> + gpa_t addr, int len, void *val)
> +{
> + struct vgic_io_device *iodev = container_of(this,
> + struct vgic_io_device, dev);
> + u32 intid = (addr - iodev->base_addr);
> + int i;
> +
> + for (i = 0; i < len; i++) {
> + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
> +
> + spin_lock(&irq->irq_lock);
> + ((u8 *)val)[i] = irq->source;
> + spin_unlock(&irq->irq_lock);

you don't need the spinlock here

> + }
> + return 0;
> +}
> +
> +static int vgic_mmio_write_sgipendc(struct kvm_vcpu *vcpu,
> + struct kvm_io_device *this,
> + gpa_t addr, int len, const void *val)
> +{
> + struct vgic_io_device *iodev = container_of(this,
> + struct vgic_io_device, dev);
> + u32 intid = (addr - iodev->base_addr);
> + int i;
> +
> + for (i = 0; i < len; i++) {
> + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
> +
> + spin_lock(&irq->irq_lock);
> + irq->source &= ~((u8 *)val)[i];

don't you also need to check if source == 0 and lower pending in this
case?

> + spin_unlock(&irq->irq_lock);
> + }
> + return 0;
> +}
> +
> +static int vgic_mmio_write_sgipends(struct kvm_vcpu *vcpu,
> + struct kvm_io_device *this,
> + gpa_t addr, int len, const void *val)
> +{
> + struct vgic_io_device *iodev = container_of(this,
> + struct vgic_io_device, dev);
> + u32 intid = (addr - iodev->base_addr);
> + int i;
> +
> + for (i = 0; i < len; i++) {
> + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
> +
> + spin_lock(&irq->irq_lock);
> + irq->source |= ((u8 *)val)[i];

don't you need to set pending and queue in this case?

> + spin_unlock(&irq->irq_lock);
> + }
> + return 0;
> +}
> +
> struct vgic_register_region vgic_v2_dist_registers[] = {
> REGISTER_DESC_WITH_LENGTH(GIC_DIST_CTRL,
> vgic_mmio_read_v2_misc, vgic_mmio_write_v2_misc, 12),
> @@ -582,9 +621,9 @@ struct vgic_register_region vgic_v2_dist_registers[] = {
> REGISTER_DESC_WITH_LENGTH(GIC_DIST_SOFTINT,
> vgic_mmio_read_raz, vgic_mmio_write_sgir, 4),
> REGISTER_DESC_WITH_LENGTH(GIC_DIST_SGI_PENDING_CLEAR,
> - vgic_mmio_read_nyi, vgic_mmio_write_nyi, 16),
> + vgic_mmio_read_sgipend, vgic_mmio_write_sgipendc, 16),
> REGISTER_DESC_WITH_LENGTH(GIC_DIST_SGI_PENDING_SET,
> - vgic_mmio_read_nyi, vgic_mmio_write_nyi, 16),
> + vgic_mmio_read_sgipend, vgic_mmio_write_sgipends, 16),
> };
>
> /*
> --
> 2.7.3
>