diff options
Diffstat (limited to 'virt/kvm/arm/vgic/vgic-mmio.c')
-rw-r--r-- | virt/kvm/arm/vgic/vgic-mmio.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/virt/kvm/arm/vgic/vgic-mmio.c b/virt/kvm/arm/vgic/vgic-mmio.c index d8dc8f6480dd..79a4622dad04 100644 --- a/virt/kvm/arm/vgic/vgic-mmio.c +++ b/virt/kvm/arm/vgic/vgic-mmio.c @@ -155,6 +155,87 @@ void vgic_mmio_write_cpending(struct kvm_vcpu *vcpu, } } +unsigned long vgic_mmio_read_active(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len) +{ + u32 intid = VGIC_ADDR_TO_INTID(addr, 1); + u32 value = 0; + int i; + + /* Loop over all IRQs affected by this read */ + for (i = 0; i < len * 8; i++) { + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i); + + if (irq->active) + value |= (1U << i); + } + + return value; +} + +void vgic_mmio_write_cactive(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len, + unsigned long val) +{ + u32 intid = VGIC_ADDR_TO_INTID(addr, 1); + int i; + + kvm_arm_halt_guest(vcpu->kvm); + for_each_set_bit(i, &val, len * 8) { + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i); + + spin_lock(&irq->irq_lock); + /* + * If this virtual IRQ was written into a list register, we + * have to make sure the CPU that runs the VCPU thread has + * synced back LR state to the struct vgic_irq. We can only + * know this for sure, when either this irq is not assigned to + * anyone's AP list anymore, or the VCPU thread is not + * running on any CPUs. + * + * In the opposite case, we know the VCPU thread may be on its + * way back from the guest and still has to sync back this + * IRQ, so we release and re-acquire the spin_lock to let the + * other thread sync back the IRQ. + */ + while (irq->vcpu && /* IRQ may have state in an LR somewhere */ + irq->vcpu->cpu != -1) /* VCPU thread is running */ + cond_resched_lock(&irq->irq_lock); + + irq->active = false; + spin_unlock(&irq->irq_lock); + } + kvm_arm_resume_guest(vcpu->kvm); +} + +void vgic_mmio_write_sactive(struct kvm_vcpu *vcpu, + gpa_t addr, unsigned int len, + unsigned long val) +{ + u32 intid = VGIC_ADDR_TO_INTID(addr, 1); + int i; + + for_each_set_bit(i, &val, len * 8) { + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i); + + spin_lock(&irq->irq_lock); + + /* + * If the IRQ was already active or there is no target VCPU + * assigned at the moment, then just proceed. + */ + if (irq->active || !irq->target_vcpu) { + irq->active = true; + + spin_unlock(&irq->irq_lock); + continue; + } + + irq->active = true; + vgic_queue_irq_unlock(vcpu->kvm, irq); + } +} + static int match_region(const void *key, const void *elt) { const unsigned int offset = (unsigned long)key; |