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 34 #ifndef for_each_valid_pfn 35 #define for_each_valid_pfn(pfn, start_pfn, end_pfn) \ 36 for ((pfn) = max_t(unsigned long, (start_pfn), ARCH_PFN_OFFSET); \ 37 (pfn) < min_t(unsigned long, (end_pfn), \ 38 ARCH_PFN_OFFSET + max_mapnr); \ 39 (pfn)++) 40 #endif /* for_each_valid_pfn */ 41 #endif /* valid_pfn */ 42 43 #elif defined(CONFIG_SPARSEMEM_VMEMMAP) 44 45 /* memmap is virtually contiguous. */ 46 #define __pfn_to_page(pfn) (vmemmap + (pfn)) 47 #define __page_to_pfn(page) (unsigned long)((page) - vmemmap) 48 49 #elif defined(CONFIG_SPARSEMEM) 50 /* 51 * Note: section's mem_map is encoded to reflect its start_pfn. 52 * section[i].section_mem_map == mem_map's address - start_pfn; 53 */ 54 #define __page_to_pfn(pg) \ 55 ({ const struct page *__pg = (pg); \ 56 int __sec = page_to_section(__pg); \ 57 (unsigned long)(__pg - __section_mem_map_addr(__nr_to_section(__sec))); \ 58 }) 59 60 #define __pfn_to_page(pfn) \ 61 ({ unsigned long __pfn = (pfn); \ 62 struct mem_section *__sec = __pfn_to_section(__pfn); \ 63 __section_mem_map_addr(__sec) + __pfn; \ 64 }) 65 #endif /* CONFIG_FLATMEM/SPARSEMEM */ 66 67 /* 68 * Convert a physical address to a Page Frame Number and back 69 */ 70 #define __phys_to_pfn(paddr) PHYS_PFN(paddr) 71 #define __pfn_to_phys(pfn) PFN_PHYS(pfn) 72 73 #define page_to_pfn __page_to_pfn 74 #define pfn_to_page __pfn_to_page 75 76 #ifdef CONFIG_DEBUG_VIRTUAL 77 #define page_to_phys(page) \ 78 ({ \ 79 unsigned long __pfn = page_to_pfn(page); \ 80 \ 81 WARN_ON_ONCE(!pfn_valid(__pfn)); \ 82 PFN_PHYS(__pfn); \ 83 }) 84 #else 85 #define page_to_phys(page) PFN_PHYS(page_to_pfn(page)) 86 #endif /* CONFIG_DEBUG_VIRTUAL */ 87 #define phys_to_page(phys) pfn_to_page(PHYS_PFN(phys)) 88 89 #endif /* __ASSEMBLY__ */ 90 91 #endif 92