xref: /linux/mm/bootmem_info.c (revision d057ac484a370f90d0353b30ad0fab2b4f1adf27)
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 
16 void get_page_bootmem(unsigned long info, struct page *page, unsigned long type)
17 {
18 	page->freelist = (void *)type;
19 	SetPagePrivate(page);
20 	set_page_private(page, info);
21 	page_ref_inc(page);
22 }
23 
24 void put_page_bootmem(struct page *page)
25 {
26 	unsigned long type;
27 
28 	type = (unsigned long) page->freelist;
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->freelist = NULL;
34 		ClearPagePrivate(page);
35 		set_page_private(page, 0);
36 		INIT_LIST_HEAD(&page->lru);
37 		free_reserved_page(page);
38 	}
39 }
40 
41 #ifndef CONFIG_SPARSEMEM_VMEMMAP
42 static void __init register_page_bootmem_info_section(unsigned long start_pfn)
43 {
44 	unsigned long mapsize, section_nr, i;
45 	struct mem_section *ms;
46 	struct page *page, *memmap;
47 	struct mem_section_usage *usage;
48 
49 	section_nr = pfn_to_section_nr(start_pfn);
50 	ms = __nr_to_section(section_nr);
51 
52 	/* Get section's memmap address */
53 	memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
54 
55 	/*
56 	 * Get page for the memmap's phys address
57 	 * XXX: need more consideration for sparse_vmemmap...
58 	 */
59 	page = virt_to_page(memmap);
60 	mapsize = sizeof(struct page) * PAGES_PER_SECTION;
61 	mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
62 
63 	/* remember memmap's page */
64 	for (i = 0; i < mapsize; i++, page++)
65 		get_page_bootmem(section_nr, page, SECTION_INFO);
66 
67 	usage = ms->usage;
68 	page = virt_to_page(usage);
69 
70 	mapsize = PAGE_ALIGN(mem_section_usage_size()) >> PAGE_SHIFT;
71 
72 	for (i = 0; i < mapsize; i++, page++)
73 		get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
74 
75 }
76 #else /* CONFIG_SPARSEMEM_VMEMMAP */
77 static void __init register_page_bootmem_info_section(unsigned long start_pfn)
78 {
79 	unsigned long mapsize, section_nr, i;
80 	struct mem_section *ms;
81 	struct page *page, *memmap;
82 	struct mem_section_usage *usage;
83 
84 	section_nr = pfn_to_section_nr(start_pfn);
85 	ms = __nr_to_section(section_nr);
86 
87 	memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
88 
89 	register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION);
90 
91 	usage = ms->usage;
92 	page = virt_to_page(usage);
93 
94 	mapsize = PAGE_ALIGN(mem_section_usage_size()) >> PAGE_SHIFT;
95 
96 	for (i = 0; i < mapsize; i++, page++)
97 		get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
98 }
99 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
100 
101 void __init register_page_bootmem_info_node(struct pglist_data *pgdat)
102 {
103 	unsigned long i, pfn, end_pfn, nr_pages;
104 	int node = pgdat->node_id;
105 	struct page *page;
106 
107 	nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT;
108 	page = virt_to_page(pgdat);
109 
110 	for (i = 0; i < nr_pages; i++, page++)
111 		get_page_bootmem(node, page, NODE_INFO);
112 
113 	pfn = pgdat->node_start_pfn;
114 	end_pfn = pgdat_end_pfn(pgdat);
115 
116 	/* register section info */
117 	for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
118 		/*
119 		 * Some platforms can assign the same pfn to multiple nodes - on
120 		 * node0 as well as nodeN.  To avoid registering a pfn against
121 		 * multiple nodes we check that this pfn does not already
122 		 * reside in some other nodes.
123 		 */
124 		if (pfn_valid(pfn) && (early_pfn_to_nid(pfn) == node))
125 			register_page_bootmem_info_section(pfn);
126 	}
127 }
128