1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Bootmem core functions.
4 *
5 * Copyright (c) 2020, Bytedance.
6 *
7 * Author: Muchun Song <songmuchun@bytedance.com>
8 *
9 */
10 #include <linux/mm.h>
11 #include <linux/compiler.h>
12 #include <linux/memblock.h>
13 #include <linux/bootmem_info.h>
14 #include <linux/memory_hotplug.h>
15 #include <linux/kmemleak.h>
16
get_page_bootmem(unsigned long info,struct page * page,unsigned long type)17 void get_page_bootmem(unsigned long info, struct page *page, unsigned long type)
18 {
19 page->index = type;
20 SetPagePrivate(page);
21 set_page_private(page, info);
22 page_ref_inc(page);
23 }
24
put_page_bootmem(struct page * page)25 void put_page_bootmem(struct page *page)
26 {
27 unsigned long type = page->index;
28
29 BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
30 type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE);
31
32 if (page_ref_dec_return(page) == 1) {
33 page->index = 0;
34 ClearPagePrivate(page);
35 set_page_private(page, 0);
36 INIT_LIST_HEAD(&page->lru);
37 kmemleak_free_part_phys(PFN_PHYS(page_to_pfn(page)), PAGE_SIZE);
38 free_reserved_page(page);
39 }
40 }
41
42 #ifndef CONFIG_SPARSEMEM_VMEMMAP
register_page_bootmem_info_section(unsigned long start_pfn)43 static void __init register_page_bootmem_info_section(unsigned long start_pfn)
44 {
45 unsigned long mapsize, section_nr, i;
46 struct mem_section *ms;
47 struct page *page, *memmap;
48 struct mem_section_usage *usage;
49
50 section_nr = pfn_to_section_nr(start_pfn);
51 ms = __nr_to_section(section_nr);
52
53 /* Get section's memmap address */
54 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
55
56 /*
57 * Get page for the memmap's phys address
58 * XXX: need more consideration for sparse_vmemmap...
59 */
60 page = virt_to_page(memmap);
61 mapsize = sizeof(struct page) * PAGES_PER_SECTION;
62 mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
63
64 /* remember memmap's page */
65 for (i = 0; i < mapsize; i++, page++)
66 get_page_bootmem(section_nr, page, SECTION_INFO);
67
68 usage = ms->usage;
69 page = virt_to_page(usage);
70
71 mapsize = PAGE_ALIGN(mem_section_usage_size()) >> PAGE_SHIFT;
72
73 for (i = 0; i < mapsize; i++, page++)
74 get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
75
76 }
77 #else /* CONFIG_SPARSEMEM_VMEMMAP */
register_page_bootmem_info_section(unsigned long start_pfn)78 static void __init register_page_bootmem_info_section(unsigned long start_pfn)
79 {
80 unsigned long mapsize, section_nr, i;
81 struct mem_section *ms;
82 struct page *page, *memmap;
83 struct mem_section_usage *usage;
84
85 section_nr = pfn_to_section_nr(start_pfn);
86 ms = __nr_to_section(section_nr);
87
88 memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
89
90 register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION);
91
92 usage = ms->usage;
93 page = virt_to_page(usage);
94
95 mapsize = PAGE_ALIGN(mem_section_usage_size()) >> PAGE_SHIFT;
96
97 for (i = 0; i < mapsize; i++, page++)
98 get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
99 }
100 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
101
register_page_bootmem_info_node(struct pglist_data * pgdat)102 void __init register_page_bootmem_info_node(struct pglist_data *pgdat)
103 {
104 unsigned long i, pfn, end_pfn, nr_pages;
105 int node = pgdat->node_id;
106 struct page *page;
107
108 nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT;
109 page = virt_to_page(pgdat);
110
111 for (i = 0; i < nr_pages; i++, page++)
112 get_page_bootmem(node, page, NODE_INFO);
113
114 pfn = pgdat->node_start_pfn;
115 end_pfn = pgdat_end_pfn(pgdat);
116
117 /* register section info */
118 for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
119 /*
120 * Some platforms can assign the same pfn to multiple nodes - on
121 * node0 as well as nodeN. To avoid registering a pfn against
122 * multiple nodes we check that this pfn does not already
123 * reside in some other nodes.
124 */
125 if (pfn_valid(pfn) && (early_pfn_to_nid(pfn) == node))
126 register_page_bootmem_info_section(pfn);
127 }
128 }
129