linux/mm/bootmem_info.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Bootmem core functions.
 *
 * Copyright (c) 2020, Bytedance.
 *
 *     Author: Muchun Song <[email protected]>
 *
 */
#include <linux/mm.h>
#include <linux/compiler.h>
#include <linux/memblock.h>
#include <linux/bootmem_info.h>
#include <linux/memory_hotplug.h>
#include <linux/kmemleak.h>

void get_page_bootmem(unsigned long info, struct page *page, unsigned long type)
{ … }

void put_page_bootmem(struct page *page)
{ … }

#ifndef CONFIG_SPARSEMEM_VMEMMAP
static void __init register_page_bootmem_info_section(unsigned long start_pfn)
{
	unsigned long mapsize, section_nr, i;
	struct mem_section *ms;
	struct page *page, *memmap;
	struct mem_section_usage *usage;

	section_nr = pfn_to_section_nr(start_pfn);
	ms = __nr_to_section(section_nr);

	/* Get section's memmap address */
	memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);

	/*
	 * Get page for the memmap's phys address
	 * XXX: need more consideration for sparse_vmemmap...
	 */
	page = virt_to_page(memmap);
	mapsize = sizeof(struct page) * PAGES_PER_SECTION;
	mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;

	/* remember memmap's page */
	for (i = 0; i < mapsize; i++, page++)
		get_page_bootmem(section_nr, page, SECTION_INFO);

	usage = ms->usage;
	page = virt_to_page(usage);

	mapsize = PAGE_ALIGN(mem_section_usage_size()) >> PAGE_SHIFT;

	for (i = 0; i < mapsize; i++, page++)
		get_page_bootmem(section_nr, page, MIX_SECTION_INFO);

}
#else /* CONFIG_SPARSEMEM_VMEMMAP */
static void __init register_page_bootmem_info_section(unsigned long start_pfn)
{ … }
#endif /* !CONFIG_SPARSEMEM_VMEMMAP */

void __init register_page_bootmem_info_node(struct pglist_data *pgdat)
{ … }