/* *  linux/mm/memory_hotplug.c * *  Copyright (C) */ #include <linux/config.h>#include <linux/stddef.h>#include <linux/mm.h>#include <linux/swap.h>#include <linux/interrupt.h>#include <linux/pagemap.h>#include <linux/bootmem.h>#include <linux/compiler.h>#include <linux/module.h>#include <linux/pagevec.h>#include <linux/slab.h>#include <linux/sysctl.h>#include <linux/cpu.h>#include <linux/memory.h>#include <linux/memory_hotplug.h>#include <linux/highmem.h>#include <linux/vmalloc.h> #include <asm/tlbflush.h> extern void zonetable_add(struct zone *zone, int nid, int zid, unsigned long pfn,			  unsigned long size);static void __add_zone(struct zone *zone, unsigned long phys_start_pfn){	struct pglist_data *pgdat = zone->zone_pgdat;	int nr_pages = PAGES_PER_SECTION;	int nid = pgdat->node_id;	int zone_type; 	zone_type = zone - pgdat->node_zones;	memmap_init_zone(nr_pages, nid, zone_type, phys_start_pfn);	zonetable_add(zone, nid, zone_type, phys_start_pfn, nr_pages);} extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,				  int nr_pages);static int __add_section(struct zone *zone, unsigned long phys_start_pfn){	int nr_pages = PAGES_PER_SECTION;	int ret; 	ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages); 	if (ret < 0)		return ret; 	__add_zone(zone, phys_start_pfn);	return register_new_memory(__pfn_to_section(phys_start_pfn));} /* * Reasonably generic function for adding memory.  It is * expected that archs that support memory hotplug will * call this function after deciding the zone to which to * add the new pages. */int __add_pages(struct zone *zone, unsigned long phys_start_pfn,		 unsigned long nr_pages){	unsigned long i;	int err = 0; 	for (i = 0; i < nr_pages; i += PAGES_PER_SECTION) {		err = __add_section(zone, phys_start_pfn + i); 		/* We want to keep adding the rest of the		 * sections if the first ones already exist		 */		if (err && (err != -EEXIST))			break;	} 	return err;}EXPORT_SYMBOL_GPL(__add_pages); static void grow_zone_span(struct zone *zone,		unsigned long start_pfn, unsigned long end_pfn){	unsigned long old_zone_end_pfn; 	zone_span_writelock(zone); 	old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;	if (start_pfn < zone->zone_start_pfn)		zone->zone_start_pfn = start_pfn; 	zone->spanned_pages = max(old_zone_end_pfn, end_pfn) -				zone->zone_start_pfn; 	zone_span_writeunlock(zone);} static void grow_pgdat_span(struct pglist_data *pgdat,		unsigned long start_pfn, unsigned long end_pfn){	unsigned long old_pgdat_end_pfn =		pgdat->node_start_pfn + pgdat->node_spanned_pages; 	if (start_pfn < pgdat->node_start_pfn)		pgdat->node_start_pfn = start_pfn; 	pgdat->node_spanned_pages = max(old_pgdat_end_pfn, end_pfn) -					pgdat->node_start_pfn;} int online_pages(unsigned long pfn, unsigned long nr_pages){	unsigned long i;	unsigned long flags;	unsigned long onlined_pages = 0;	struct zone *zone; 	/*	 * This doesn't need a lock to do pfn_to_page().	 * The section can't be removed here because of the	 * memory_block->state_sem.	 */	zone = page_zone(pfn_to_page(pfn));	pgdat_resize_lock(zone->zone_pgdat, &flags);	grow_zone_span(zone, pfn, pfn + nr_pages);	grow_pgdat_span(zone->zone_pgdat, pfn, pfn + nr_pages);	pgdat_resize_unlock(zone->zone_pgdat, &flags); 	for (i = 0; i < nr_pages; i++) {		struct page *page = pfn_to_page(pfn + i);		online_page(page);		onlined_pages++;	}	zone->present_pages += onlined_pages;	zone->zone_pgdat->node_present_pages += onlined_pages; 	setup_per_zone_pages_min(); 	return 0;}