70 lines · c
1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef __ASM_MEMORY_MODEL_H3#define __ASM_MEMORY_MODEL_H4 5#include <linux/pfn.h>6 7#ifndef __ASSEMBLY__8 9/*10 * supports 3 memory models.11 */12#if defined(CONFIG_FLATMEM)13 14#ifndef ARCH_PFN_OFFSET15#define ARCH_PFN_OFFSET (0UL)16#endif17 18#define __pfn_to_page(pfn) (mem_map + ((pfn) - ARCH_PFN_OFFSET))19#define __page_to_pfn(page) ((unsigned long)((page) - mem_map) + \20 ARCH_PFN_OFFSET)21 22#ifndef pfn_valid23static inline int pfn_valid(unsigned long pfn)24{25 /* avoid <linux/mm.h> include hell */26 extern unsigned long max_mapnr;27 unsigned long pfn_offset = ARCH_PFN_OFFSET;28 29 return pfn >= pfn_offset && (pfn - pfn_offset) < max_mapnr;30}31#define pfn_valid pfn_valid32#endif33 34#elif defined(CONFIG_SPARSEMEM_VMEMMAP)35 36/* memmap is virtually contiguous. */37#define __pfn_to_page(pfn) (vmemmap + (pfn))38#define __page_to_pfn(page) (unsigned long)((page) - vmemmap)39 40#elif defined(CONFIG_SPARSEMEM)41/*42 * Note: section's mem_map is encoded to reflect its start_pfn.43 * section[i].section_mem_map == mem_map's address - start_pfn;44 */45#define __page_to_pfn(pg) \46({ const struct page *__pg = (pg); \47 int __sec = page_to_section(__pg); \48 (unsigned long)(__pg - __section_mem_map_addr(__nr_to_section(__sec))); \49})50 51#define __pfn_to_page(pfn) \52({ unsigned long __pfn = (pfn); \53 struct mem_section *__sec = __pfn_to_section(__pfn); \54 __section_mem_map_addr(__sec) + __pfn; \55})56#endif /* CONFIG_FLATMEM/SPARSEMEM */57 58/*59 * Convert a physical address to a Page Frame Number and back60 */61#define __phys_to_pfn(paddr) PHYS_PFN(paddr)62#define __pfn_to_phys(pfn) PFN_PHYS(pfn)63 64#define page_to_pfn __page_to_pfn65#define pfn_to_page __pfn_to_page66 67#endif /* __ASSEMBLY__ */68 69#endif70