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#elif defined(CONFIG_SPARSEMEM_VMEMMAP) 23 24/* memmap is virtually contiguous. */ 25#define __pfn_to_page(pfn) (vmemmap + (pfn)) 26#define __page_to_pfn(page) (unsigned long)((page) - vmemmap) 27 28#elif defined(CONFIG_SPARSEMEM) 29/* 30 * Note: section's mem_map is encoded to reflect its start_pfn. 31 * section[i].section_mem_map == mem_map's address - start_pfn; 32 */ 33#define __page_to_pfn(pg) \ 34({ const struct page *__pg = (pg); \ 35 int __sec = page_to_section(__pg); \ 36 (unsigned long)(__pg - __section_mem_map_addr(__nr_to_section(__sec))); \ 37}) 38 39#define __pfn_to_page(pfn) \ 40({ unsigned long __pfn = (pfn); \ 41 struct mem_section *__sec = __pfn_to_section(__pfn); \ 42 __section_mem_map_addr(__sec) + __pfn; \ 43}) 44#endif /* CONFIG_FLATMEM/SPARSEMEM */ 45 46/* 47 * Convert a physical address to a Page Frame Number and back 48 */ 49#define __phys_to_pfn(paddr) PHYS_PFN(paddr) 50#define __pfn_to_phys(pfn) PFN_PHYS(pfn) 51 52#define page_to_pfn __page_to_pfn 53#define pfn_to_page __pfn_to_page 54 55#endif /* __ASSEMBLY__ */ 56 57#endif 58