1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef __ASM_MEMORY_MODEL_H 3#define __ASM_MEMORY_MODEL_H 4 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_OFFSET 15#define ARCH_PFN_OFFSET (0UL) 16#endif 17 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_valid 23static 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_valid 32#endif 33 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 back 60 */ 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_pfn 65#define pfn_to_page __pfn_to_page 66 67#endif /* __ASSEMBLY__ */ 68 69#endif 70