pci_request_regions_exclusive (9) - Linux Manuals
pci_request_regions_exclusive: Reserved PCI I/O and memory resources
pci_request_regions_exclusive - Reserved PCI I/O and memory resources
int pci_request_regions_exclusive(struct pci_dev
* pdev, const char * res_name);
- PCI device whose resources are to be reserved
- Name to be associated with resource.
Mark all PCI regions associated with PCI device pdev as being reserved by owner res_name. Do not access any address inside the PCI regions unless this call returns successfully.
pci_request_regions_exclusive will mark the region so that /dev/mem and the sysfs MMIO access will not be allowed.