1 /* 2 * The PCI Library -- Physical memory mapping API 3 * 4 * Copyright (c) 2023 Pali Rohár <[email protected]> 5 * 6 * Can be freely distributed and used under the terms of the GNU GPL v2+ 7 * 8 * SPDX-License-Identifier: GPL-2.0-or-later 9 */ 10 11 struct physmem; 12 13 void physmem_init_config(struct pci_access *a); 14 int physmem_access(struct pci_access *a, int w); 15 struct physmem *physmem_open(struct pci_access *a, int w); 16 void physmem_close(struct physmem *physmem); 17 long physmem_get_pagesize(struct physmem *physmem); 18 19 /* 20 * physmem_map returns ptr on success, (void *)-1 on error and sets errno compatible with POSIX mmap(): 21 * - EBADF - invalid physmem argument 22 * - EINVAL - invalid or unaligned addr argument 23 * - EACCES - write access requested but physmem was opened without write access 24 * - ENOSYS - physmem argument does not support physical address mapping at all 25 * - ENXIO - addr/length range was rejected by system (e.g. range not accessible or not available) 26 * - EOVERFLOW - addr/length range is out of the physical address space (e.g. does not fit into signed 32-bit off_t type on 32-bit systems) 27 * - EACCES - generic unknown error for djgpp and windows 28 */ 29 void *physmem_map(struct physmem *physmem, u64 addr, size_t length, int w); 30 31 /* 32 * Unmap physical memory mapping, ptr and length must be exactly same as for physmem_map(), unmapping just subrange is not allowed. 33 * physmem_unmap returns 0 on success, -1 on error and sets errno: 34 * - EBADF - invalid physmem argument 35 * - EINVAL - invalid ptr/length argument 36 * - EPERM - ptr/length range cannot be unmapped due to access permission checks (e.g. page marked as immutable) 37 * - ENOSYS - physmem argument does not support physical address unmapping at all (e.g. every mapping stays active until application terminates) 38 * - EACCES - generic unknown error for djgpp and windows 39 */ 40 int physmem_unmap(struct physmem *physmem, void *ptr, size_t length); 41