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