Xen PCI Frontend

modulename: xen-pcifront.ko

configname: CONFIG_XEN_PCIDEV_FRONTEND

Linux Kernel Configuration
└─>Bus options (PCI etc.)
└─>Xen PCI Frontend
In linux kernel since version 3.10 (release Date: 2013-06-30)  
The PCI device frontend driver allows the kernel to import arbitrary
PCI devices from a PCI backend to support PCI driver domains.

source code:
drivers/pci/xen-pcifront.c