Man page 9 : pci_mmap_legacy_mem

pci_mmap_legacy_mem - map legacy PCI memory into user memory space

int pci_mmap_legacy_mem(struct file *  filp , struct kobject *  kobj , struct bin_attribute *  attr , struct vm_area_struct *  vma );

filp
    open sysfs file

kobj
    kobject corresponding to device to be mapped

attr
    struct bin_attribute for this file

vma
    struct vm_area_struct passed to mmap

Uses an arch specific callback, pci_mmap_legacy_mem_page_range, to mmap legacy memory space (first meg of bus space) into application virtual memory space.