/* SPDX-License-Identifier: GPL-2.0-or-later *//* * sparse.h: * * mm/ internal sparse and sparse-vmemmap declarations */ #ifndef __MM_SPARSE_H#define __MM_SPARSE_H #include <linux/mmzone.h> /* * mm/sparse.c */#ifdef CONFIG_SPARSEMEMvoid sparse_init(void);int sparse_index_init(unsigned long section_nr, int nid); static inline void sparse_init_one_section(struct mem_section *ms,		unsigned long pnum, struct page *mem_map,		struct mem_section_usage *usage, unsigned long flags){	unsigned long coded_mem_map; 	BUILD_BUG_ON(SECTION_MAP_LAST_BIT > PFN_SECTION_SHIFT); 	/*	 * We encode the start PFN of the section into the mem_map such that	 * page_to_pfn() on !CONFIG_SPARSEMEM_VMEMMAP can simply subtract it	 * from the page pointer to obtain the PFN.	 */	coded_mem_map = (unsigned long)(mem_map - section_nr_to_pfn(pnum));	VM_WARN_ON_ONCE(coded_mem_map & ~SECTION_MAP_MASK); 	ms->section_mem_map &= ~SECTION_MAP_MASK;	ms->section_mem_map |= coded_mem_map;	ms->section_mem_map |= flags | SECTION_HAS_MEM_MAP;	ms->usage = usage;} static inline void __section_mark_present(struct mem_section *ms,		unsigned long section_nr){	if (section_nr > __highest_present_section_nr)		__highest_present_section_nr = section_nr; 	ms->section_mem_map |= SECTION_MARKED_PRESENT;} static inline size_t mem_section_usage_size(void){	return struct_size_t(struct mem_section_usage, pageblock_flags,			     BITS_TO_LONGS(SECTION_BLOCKFLAGS_BITS));}#elsestatic inline void sparse_init(void) {}#endif /* CONFIG_SPARSEMEM */ /* * mm/sparse-vmemmap.c */#ifdef CONFIG_SPARSEMEM_VMEMMAPvoid sparse_init_subsection_map(void);#elsestatic inline void sparse_init_subsection_map(void) {}#endif /* CONFIG_SPARSEMEM_VMEMMAP */ #endif /* __MM_SPARSE_H */