1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * sparse.h:
4 *
5 * mm/ internal sparse and sparse-vmemmap declarations
6 */
7
8 #ifndef __MM_SPARSE_H
9 #define __MM_SPARSE_H
10
11 #include <linux/mmzone.h>
12
13 /*
14 * mm/sparse.c
15 */
16 #ifdef CONFIG_SPARSEMEM
17 void sparse_init(void);
18 int sparse_index_init(unsigned long section_nr, int nid);
19
sparse_init_one_section(struct mem_section * ms,unsigned long pnum,struct page * mem_map,struct mem_section_usage * usage,unsigned long flags)20 static inline void sparse_init_one_section(struct mem_section *ms,
21 unsigned long pnum, struct page *mem_map,
22 struct mem_section_usage *usage, unsigned long flags)
23 {
24 unsigned long coded_mem_map;
25
26 BUILD_BUG_ON(SECTION_MAP_LAST_BIT > PFN_SECTION_SHIFT);
27
28 /*
29 * We encode the start PFN of the section into the mem_map such that
30 * page_to_pfn() on !CONFIG_SPARSEMEM_VMEMMAP can simply subtract it
31 * from the page pointer to obtain the PFN.
32 */
33 coded_mem_map = (unsigned long)(mem_map - section_nr_to_pfn(pnum));
34 VM_WARN_ON_ONCE(coded_mem_map & ~SECTION_MAP_MASK);
35
36 ms->section_mem_map &= ~SECTION_MAP_MASK;
37 ms->section_mem_map |= coded_mem_map;
38 ms->section_mem_map |= flags | SECTION_HAS_MEM_MAP;
39 ms->usage = usage;
40 }
41
__section_mark_present(struct mem_section * ms,unsigned long section_nr)42 static inline void __section_mark_present(struct mem_section *ms,
43 unsigned long section_nr)
44 {
45 if (section_nr > __highest_present_section_nr)
46 __highest_present_section_nr = section_nr;
47
48 ms->section_mem_map |= SECTION_MARKED_PRESENT;
49 }
50
mem_section_usage_size(void)51 static inline size_t mem_section_usage_size(void)
52 {
53 return struct_size_t(struct mem_section_usage, pageblock_flags,
54 BITS_TO_LONGS(SECTION_BLOCKFLAGS_BITS));
55 }
56 #else
sparse_init(void)57 static inline void sparse_init(void) {}
58 #endif /* CONFIG_SPARSEMEM */
59
60 /*
61 * mm/sparse-vmemmap.c
62 */
63 #ifdef CONFIG_SPARSEMEM_VMEMMAP
64 void sparse_init_subsection_map(void);
65 #else
sparse_init_subsection_map(void)66 static inline void sparse_init_subsection_map(void) {}
67 #endif /* CONFIG_SPARSEMEM_VMEMMAP */
68
69 #endif /* __MM_SPARSE_H */
70