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 /* avoid <linux/mm.h> include hell */ 23 extern unsigned long max_mapnr; 24 25 #ifndef pfn_valid pfn_valid(unsigned long pfn)26static inline int pfn_valid(unsigned long pfn) 27 { 28 unsigned long pfn_offset = ARCH_PFN_OFFSET; 29 30 return pfn >= pfn_offset && (pfn - pfn_offset) < max_mapnr; 31 } 32 #define pfn_valid pfn_valid 33 #endif 34 35 #elif defined(CONFIG_SPARSEMEM_VMEMMAP) 36 37 /* memmap is virtually contiguous. */ 38 #define __pfn_to_page(pfn) (vmemmap + (pfn)) 39 #define __page_to_pfn(page) (unsigned long)((page) - vmemmap) 40 41 #elif defined(CONFIG_SPARSEMEM) 42 /* 43 * Note: section's mem_map is encoded to reflect its start_pfn. 44 * section[i].section_mem_map == mem_map's address - start_pfn; 45 */ 46 #define __page_to_pfn(pg) \ 47 ({ const struct page *__pg = (pg); \ 48 int __sec = page_to_section(__pg); \ 49 (unsigned long)(__pg - __section_mem_map_addr(__nr_to_section(__sec))); \ 50 }) 51 52 #define __pfn_to_page(pfn) \ 53 ({ unsigned long __pfn = (pfn); \ 54 struct mem_section *__sec = __pfn_to_section(__pfn); \ 55 __section_mem_map_addr(__sec) + __pfn; \ 56 }) 57 #endif /* CONFIG_FLATMEM/SPARSEMEM */ 58 59 /* 60 * Convert a physical address to a Page Frame Number and back 61 */ 62 #define __phys_to_pfn(paddr) PHYS_PFN(paddr) 63 #define __pfn_to_phys(pfn) PFN_PHYS(pfn) 64 65 #define page_to_pfn __page_to_pfn 66 #define pfn_to_page __pfn_to_page 67 68 #ifdef CONFIG_DEBUG_VIRTUAL 69 #define page_to_phys(page) \ 70 ({ \ 71 unsigned long __pfn = page_to_pfn(page); \ 72 \ 73 WARN_ON_ONCE(!pfn_valid(__pfn)); \ 74 PFN_PHYS(__pfn); \ 75 }) 76 #else 77 #define page_to_phys(page) PFN_PHYS(page_to_pfn(page)) 78 #endif /* CONFIG_DEBUG_VIRTUAL */ 79 #define phys_to_page(phys) pfn_to_page(PHYS_PFN(phys)) 80 81 #endif /* __ASSEMBLY__ */ 82 83 #endif 84