/* SPDX-License-Identifier: GPL-2.0 */#ifndef __ASM_MEMORY_MODEL_H#define __ASM_MEMORY_MODEL_H #include <linux/pfn.h> #ifndef __ASSEMBLY__ /* * supports 3 memory models. */#if defined(CONFIG_FLATMEM) #ifndef ARCH_PFN_OFFSET#define ARCH_PFN_OFFSET		(0UL)#endif #define __pfn_to_page(pfn)	(mem_map + ((pfn) - ARCH_PFN_OFFSET))#define __page_to_pfn(page)	((unsigned long)((page) - mem_map) + \				 ARCH_PFN_OFFSET) #ifndef pfn_validstatic inline int pfn_valid(unsigned long pfn){	/* avoid <linux/mm.h> include hell */	extern unsigned long max_mapnr;	unsigned long pfn_offset = ARCH_PFN_OFFSET; 	return pfn >= pfn_offset && (pfn - pfn_offset) < max_mapnr;}#define pfn_valid pfn_valid#endif #elif defined(CONFIG_SPARSEMEM_VMEMMAP) /* memmap is virtually contiguous.  */#define __pfn_to_page(pfn)	(vmemmap + (pfn))#define __page_to_pfn(page)	(unsigned long)((page) - vmemmap) #elif defined(CONFIG_SPARSEMEM)/* * Note: section's mem_map is encoded to reflect its start_pfn. * section[i].section_mem_map == mem_map's address - start_pfn; */#define __page_to_pfn(pg)					\({	const struct page *__pg = (pg);				\	int __sec = page_to_section(__pg);			\	(unsigned long)(__pg - __section_mem_map_addr(__nr_to_section(__sec)));	\}) #define __pfn_to_page(pfn)				\({	unsigned long __pfn = (pfn);			\	struct mem_section *__sec = __pfn_to_section(__pfn);	\	__section_mem_map_addr(__sec) + __pfn;		\})#endif /* CONFIG_FLATMEM/SPARSEMEM */ /* * Convert a physical address to a Page Frame Number and back */#define	__phys_to_pfn(paddr)	PHYS_PFN(paddr)#define	__pfn_to_phys(pfn)	PFN_PHYS(pfn) #define page_to_pfn __page_to_pfn#define pfn_to_page __pfn_to_page #endif /* __ASSEMBLY__ */ #endif