irq_set_vcpu_affinity — Set vcpu affinity for the interrupt
| int irq_set_vcpu_affinity ( | unsigned int irq, | 
| void * vcpu_info ); | 
   This function uses the vCPU specific data to set the vCPU
   affinity for an irq. The vCPU specific data is passed from
   outside, such as KVM. One example code path is as below:
   KVM -> IOMMU -> irq_set_vcpu_affinity.