|S390_PCI_MMIO_WRITE(2)||System Calls Manual||S390_PCI_MMIO_WRITE(2)|
int s390_pci_mmio_write(unsigned long mmio_addr, const void *user_buffer, size_t length); int s390_pci_mmio_read(unsigned long mmio_addr, void *user_buffer, size_t length);
Note: There are no glibc wrappers for these system calls; see NOTES.
These system calls must be used instead of the simple assignment or data-transfer operations that are used to access the PCI MMIO memory areas mapped to user space on the Linux System z platform. The address specified by mmio_addr must belong to a PCI MMIO memory page mapping in the caller's address space, and the data being written or read must not cross a page boundary. The length value cannot be greater than the system page size.
- The address in mmio_addr is invalid.
- user_buffer does not point to a valid location in the caller's address space.
- Invalid length argument.
- PCI support is not enabled.
- Insufficient memory.
|2021-03-22||Linux Programmer's Manual|