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
 17void 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
 25void 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
 43static 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 */
 78static 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
102void __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}