root/mm/memory_hotplug.c
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DEFINITIONS
This source file includes following definitions.
- register_memory_resource
- release_memory_resource
- get_page_bootmem
- put_page_bootmem
- register_page_bootmem_info_section
- register_page_bootmem_info_node
- grow_zone_span
- grow_pgdat_span
- __add_zone
- __add_section
- __remove_section
- __remove_section
- __add_pages
- __remove_pages
- online_page
- online_pages_range
- online_pages
- hotadd_new_pgdat
- rollback_node_hotadd
- add_memory
- pageblock_free
- next_active_pageblock
- is_mem_section_removable
- test_pages_in_a_zone
- scan_lru_pages
- hotremove_migrate_alloc
- do_migrate_range
- offline_isolated_pages_cb
- offline_isolated_pages
- check_pages_isolated_cb
- check_pages_isolated
- offline_pages
- remove_memory
/*
* linux/mm/memory_hotplug.c
*
* Copyright (C)
*/
#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/writeback.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 <linux/ioport.h>
#include <linux/cpuset.h>
#include <linux/delay.h>
#include <linux/migrate.h>
#include <linux/page-isolation.h>
#include <asm/tlbflush.h>
#include "internal.h"
/* add this memory to iomem resource */
static struct resource *register_memory_resource(u64 start, u64 size)
{
struct resource *res;
res = kzalloc(sizeof(struct resource), GFP_KERNEL);
BUG_ON(!res);
res->name = "System RAM";
res->start = start;
res->end = start + size - 1;
res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
if (request_resource(&iomem_resource, res) < 0) {
printk("System RAM resource %llx - %llx cannot be added\n",
(unsigned long long)res->start, (unsigned long long)res->end);
kfree(res);
res = NULL;
}
return res;
}
static void release_memory_resource(struct resource *res)
{
if (!res)
return;
release_resource(res);
kfree(res);
return;
}
#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
#ifndef CONFIG_SPARSEMEM_VMEMMAP
static void get_page_bootmem(unsigned long info, struct page *page, int type)
{
atomic_set(&page->_mapcount, type);
SetPagePrivate(page);
set_page_private(page, info);
atomic_inc(&page->_count);
}
void put_page_bootmem(struct page *page)
{
int type;
type = atomic_read(&page->_mapcount);
BUG_ON(type >= -1);
if (atomic_dec_return(&page->_count) == 1) {
ClearPagePrivate(page);
set_page_private(page, 0);
reset_page_mapcount(page);
__free_pages_bootmem(page, 0);
}
}
static void register_page_bootmem_info_section(unsigned long start_pfn)
{
unsigned long *usemap, mapsize, section_nr, i;
struct mem_section *ms;
struct page *page, *memmap;
if (!pfn_valid(start_pfn))
return;
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);
usemap = __nr_to_section(section_nr)->pageblock_flags;
page = virt_to_page(usemap);
mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
for (i = 0; i < mapsize; i++, page++)
get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
}
void register_page_bootmem_info_node(struct pglist_data *pgdat)
{
unsigned long i, pfn, end_pfn, nr_pages;
int node = pgdat->node_id;
struct page *page;
struct zone *zone;
nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT;
page = virt_to_page(pgdat);
for (i = 0; i < nr_pages; i++, page++)
get_page_bootmem(node, page, NODE_INFO);
zone = &pgdat->node_zones[0];
for (; zone < pgdat->node_zones + MAX_NR_ZONES - 1; zone++) {
if (zone->wait_table) {
nr_pages = zone->wait_table_hash_nr_entries
* sizeof(wait_queue_head_t);
nr_pages = PAGE_ALIGN(nr_pages) >> PAGE_SHIFT;
page = virt_to_page(zone->wait_table);
for (i = 0; i < nr_pages; i++, page++)
get_page_bootmem(node, page, NODE_INFO);
}
}
pfn = pgdat->node_start_pfn;
end_pfn = pfn + pgdat->node_spanned_pages;
/* register_section info */
for (; pfn < end_pfn; pfn += PAGES_PER_SECTION)
register_page_bootmem_info_section(pfn);
}
#endif /* !CONFIG_SPARSEMEM_VMEMMAP */
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;
}
static int __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;
unsigned long flags;
zone_type = zone - pgdat->node_zones;
if (!zone->wait_table) {
int ret;
ret = init_currently_empty_zone(zone, phys_start_pfn,
nr_pages, MEMMAP_HOTPLUG);
if (ret)
return ret;
}
pgdat_resize_lock(zone->zone_pgdat, &flags);
grow_zone_span(zone, phys_start_pfn, phys_start_pfn + nr_pages);
grow_pgdat_span(zone->zone_pgdat, phys_start_pfn,
phys_start_pfn + nr_pages);
pgdat_resize_unlock(zone->zone_pgdat, &flags);
memmap_init_zone(nr_pages, nid, zone_type,
phys_start_pfn, MEMMAP_HOTPLUG);
return 0;
}
static int __add_section(struct zone *zone, unsigned long phys_start_pfn)
{
int nr_pages = PAGES_PER_SECTION;
int ret;
if (pfn_valid(phys_start_pfn))
return -EEXIST;
ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages);
if (ret < 0)
return ret;
ret = __add_zone(zone, phys_start_pfn);
if (ret < 0)
return ret;
return register_new_memory(__pfn_to_section(phys_start_pfn));
}
#ifdef CONFIG_SPARSEMEM_VMEMMAP
static int __remove_section(struct zone *zone, struct mem_section *ms)
{
/*
* XXX: Freeing memmap with vmemmap is not implement yet.
* This should be removed later.
*/
return -EBUSY;
}
#else
static int __remove_section(struct zone *zone, struct mem_section *ms)
{
unsigned long flags;
struct pglist_data *pgdat = zone->zone_pgdat;
int ret = -EINVAL;
if (!valid_section(ms))
return ret;
ret = unregister_memory_section(ms);
if (ret)
return ret;
pgdat_resize_lock(pgdat, &flags);
sparse_remove_one_section(zone, ms);
pgdat_resize_unlock(pgdat, &flags);
return 0;
}
#endif
/*
* 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;
int start_sec, end_sec;
/* during initialize mem_map, align hot-added range to section */
start_sec = pfn_to_section_nr(phys_start_pfn);
end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
for (i = start_sec; i <= end_sec; i++) {
err = __add_section(zone, i << PFN_SECTION_SHIFT);
/*
* EEXIST is finally dealt with by ioresource collision
* check. see add_memory() => register_memory_resource()
* Warning will be printed if there is collision.
*/
if (err && (err != -EEXIST))
break;
err = 0;
}
return err;
}
EXPORT_SYMBOL_GPL(__add_pages);
/**
* __remove_pages() - remove sections of pages from a zone
* @zone: zone from which pages need to be removed
* @phys_start_pfn: starting pageframe (must be aligned to start of a section)
* @nr_pages: number of pages to remove (must be multiple of section size)
*
* Generic helper function to remove section mappings and sysfs entries
* for the section of the memory we are removing. Caller needs to make
* sure that pages are marked reserved and zones are adjust properly by
* calling offline_pages().
*/
int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
unsigned long nr_pages)
{
unsigned long i, ret = 0;
int sections_to_remove;
/*
* We can only remove entire sections
*/
BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
BUG_ON(nr_pages % PAGES_PER_SECTION);
release_mem_region(phys_start_pfn << PAGE_SHIFT, nr_pages * PAGE_SIZE);
sections_to_remove = nr_pages / PAGES_PER_SECTION;
for (i = 0; i < sections_to_remove; i++) {
unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
ret = __remove_section(zone, __pfn_to_section(pfn));
if (ret)
break;
}
return ret;
}
EXPORT_SYMBOL_GPL(__remove_pages);
void online_page(struct page *page)
{
totalram_pages++;
num_physpages++;
#ifdef CONFIG_HIGHMEM
if (PageHighMem(page))
totalhigh_pages++;
#endif
#ifdef CONFIG_FLATMEM
max_mapnr = max(page_to_pfn(page), max_mapnr);
#endif
ClearPageReserved(page);
init_page_count(page);
__free_page(page);
}
static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
void *arg)
{
unsigned long i;
unsigned long onlined_pages = *(unsigned long *)arg;
struct page *page;
if (PageReserved(pfn_to_page(start_pfn)))
for (i = 0; i < nr_pages; i++) {
page = pfn_to_page(start_pfn + i);
online_page(page);
onlined_pages++;
}
*(unsigned long *)arg = onlined_pages;
return 0;
}
int online_pages(unsigned long pfn, unsigned long nr_pages)
{
unsigned long onlined_pages = 0;
struct zone *zone;
int need_zonelists_rebuild = 0;
int nid;
int ret;
struct memory_notify arg;
arg.start_pfn = pfn;
arg.nr_pages = nr_pages;
arg.status_change_nid = -1;
nid = page_to_nid(pfn_to_page(pfn));
if (node_present_pages(nid) == 0)
arg.status_change_nid = nid;
ret = memory_notify(MEM_GOING_ONLINE, &arg);
ret = notifier_to_errno(ret);
if (ret) {
memory_notify(MEM_CANCEL_ONLINE, &arg);
return ret;
}
/*
* This doesn't need a lock to do pfn_to_page().
* The section can't be removed here because of the
* memory_block->state_mutex.
*/
zone = page_zone(pfn_to_page(pfn));
/*
* If this zone is not populated, then it is not in zonelist.
* This means the page allocator ignores this zone.
* So, zonelist must be updated after online.
*/
if (!populated_zone(zone))
need_zonelists_rebuild = 1;
ret = walk_memory_resource(pfn, nr_pages, &onlined_pages,
online_pages_range);
if (ret) {
printk(KERN_DEBUG "online_pages %lx at %lx failed\n",
nr_pages, pfn);
memory_notify(MEM_CANCEL_ONLINE, &arg);
return ret;
}
zone->present_pages += onlined_pages;
zone->zone_pgdat->node_present_pages += onlined_pages;
setup_per_zone_pages_min();
if (onlined_pages) {
kswapd_run(zone_to_nid(zone));
node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
}
if (need_zonelists_rebuild)
build_all_zonelists();
else
vm_total_pages = nr_free_pagecache_pages();
writeback_set_ratelimit();
if (onlined_pages)
memory_notify(MEM_ONLINE, &arg);
return 0;
}
#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
static pg_data_t *hotadd_new_pgdat(int nid, u64 start)
{
struct pglist_data *pgdat;
unsigned long zones_size[MAX_NR_ZONES] = {0};
unsigned long zholes_size[MAX_NR_ZONES] = {0};
unsigned long start_pfn = start >> PAGE_SHIFT;
pgdat = arch_alloc_nodedata(nid);
if (!pgdat)
return NULL;
arch_refresh_nodedata(nid, pgdat);
/* we can use NODE_DATA(nid) from here */
/* init node's zones as empty zones, we don't have any present pages.*/
free_area_init_node(nid, zones_size, start_pfn, zholes_size);
return pgdat;
}
static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
{
arch_refresh_nodedata(nid, NULL);
arch_free_nodedata(pgdat);
return;
}
int add_memory(int nid, u64 start, u64 size)
{
pg_data_t *pgdat = NULL;
int new_pgdat = 0;
struct resource *res;
int ret;
res = register_memory_resource(start, size);
if (!res)
return -EEXIST;
if (!node_online(nid)) {
pgdat = hotadd_new_pgdat(nid, start);
if (!pgdat)
return -ENOMEM;
new_pgdat = 1;
}
/* call arch's memory hotadd */
ret = arch_add_memory(nid, start, size);
if (ret < 0)
goto error;
/* we online node here. we can't roll back from here. */
node_set_online(nid);
cpuset_track_online_nodes();
if (new_pgdat) {
ret = register_one_node(nid);
/*
* If sysfs file of new node can't create, cpu on the node
* can't be hot-added. There is no rollback way now.
* So, check by BUG_ON() to catch it reluctantly..
*/
BUG_ON(ret);
}
return ret;
error:
/* rollback pgdat allocation and others */
if (new_pgdat)
rollback_node_hotadd(nid, pgdat);
if (res)
release_memory_resource(res);
return ret;
}
EXPORT_SYMBOL_GPL(add_memory);
#ifdef CONFIG_MEMORY_HOTREMOVE
/*
* A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
* set and the size of the free page is given by page_order(). Using this,
* the function determines if the pageblock contains only free pages.
* Due to buddy contraints, a free page at least the size of a pageblock will
* be located at the start of the pageblock
*/
static inline int pageblock_free(struct page *page)
{
return PageBuddy(page) && page_order(page) >= pageblock_order;
}
/* Return the start of the next active pageblock after a given page */
static struct page *next_active_pageblock(struct page *page)
{
int pageblocks_stride;
/* Ensure the starting page is pageblock-aligned */
BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1));
/* Move forward by at least 1 * pageblock_nr_pages */
pageblocks_stride = 1;
/* If the entire pageblock is free, move to the end of free page */
if (pageblock_free(page))
pageblocks_stride += page_order(page) - pageblock_order;
return page + (pageblocks_stride * pageblock_nr_pages);
}
/* Checks if this range of memory is likely to be hot-removable. */
int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
{
int type;
struct page *page = pfn_to_page(start_pfn);
struct page *end_page = page + nr_pages;
/* Check the starting page of each pageblock within the range */
for (; page < end_page; page = next_active_pageblock(page)) {
type = get_pageblock_migratetype(page);
/*
* A pageblock containing MOVABLE or free pages is considered
* removable
*/
if (type != MIGRATE_MOVABLE && !pageblock_free(page))
return 0;
/*
* A pageblock starting with a PageReserved page is not
* considered removable.
*/
if (PageReserved(page))
return 0;
}
/* All pageblocks in the memory block are likely to be hot-removable */
return 1;
}
/*
* Confirm all pages in a range [start, end) is belongs to the same zone.
*/
static int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn)
{
unsigned long pfn;
struct zone *zone = NULL;
struct page *page;
int i;
for (pfn = start_pfn;
pfn < end_pfn;
pfn += MAX_ORDER_NR_PAGES) {
i = 0;
/* This is just a CONFIG_HOLES_IN_ZONE check.*/
while ((i < MAX_ORDER_NR_PAGES) && !pfn_valid_within(pfn + i))
i++;
if (i == MAX_ORDER_NR_PAGES)
continue;
page = pfn_to_page(pfn + i);
if (zone && page_zone(page) != zone)
return 0;
zone = page_zone(page);
}
return 1;
}
/*
* Scanning pfn is much easier than scanning lru list.
* Scan pfn from start to end and Find LRU page.
*/
int scan_lru_pages(unsigned long start, unsigned long end)
{
unsigned long pfn;
struct page *page;
for (pfn = start; pfn < end; pfn++) {
if (pfn_valid(pfn)) {
page = pfn_to_page(pfn);
if (PageLRU(page))
return pfn;
}
}
return 0;
}
static struct page *
hotremove_migrate_alloc(struct page *page,
unsigned long private,
int **x)
{
/* This should be improoooooved!! */
return alloc_page(GFP_HIGHUSER_PAGECACHE);
}
#define NR_OFFLINE_AT_ONCE_PAGES (256)
static int
do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
{
unsigned long pfn;
struct page *page;
int move_pages = NR_OFFLINE_AT_ONCE_PAGES;
int not_managed = 0;
int ret = 0;
LIST_HEAD(source);
for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) {
if (!pfn_valid(pfn))
continue;
page = pfn_to_page(pfn);
if (!page_count(page))
continue;
/*
* We can skip free pages. And we can only deal with pages on
* LRU.
*/
ret = isolate_lru_page(page, &source);
if (!ret) { /* Success */
move_pages--;
} else {
/* Becasue we don't have big zone->lock. we should
check this again here. */
if (page_count(page))
not_managed++;
#ifdef CONFIG_DEBUG_VM
printk(KERN_INFO "removing from LRU failed"
" %lx/%d/%lx\n",
pfn, page_count(page), page->flags);
#endif
}
}
ret = -EBUSY;
if (not_managed) {
if (!list_empty(&source))
putback_lru_pages(&source);
goto out;
}
ret = 0;
if (list_empty(&source))
goto out;
/* this function returns # of failed pages */
ret = migrate_pages(&source, hotremove_migrate_alloc, 0);
out:
return ret;
}
/*
* remove from free_area[] and mark all as Reserved.
*/
static int
offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages,
void *data)
{
__offline_isolated_pages(start, start + nr_pages);
return 0;
}
static void
offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
{
walk_memory_resource(start_pfn, end_pfn - start_pfn, NULL,
offline_isolated_pages_cb);
}
/*
* Check all pages in range, recoreded as memory resource, are isolated.
*/
static int
check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages,
void *data)
{
int ret;
long offlined = *(long *)data;
ret = test_pages_isolated(start_pfn, start_pfn + nr_pages);
offlined = nr_pages;
if (!ret)
*(long *)data += offlined;
return ret;
}
static long
check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
{
long offlined = 0;
int ret;
ret = walk_memory_resource(start_pfn, end_pfn - start_pfn, &offlined,
check_pages_isolated_cb);
if (ret < 0)
offlined = (long)ret;
return offlined;
}
int offline_pages(unsigned long start_pfn,
unsigned long end_pfn, unsigned long timeout)
{
unsigned long pfn, nr_pages, expire;
long offlined_pages;
int ret, drain, retry_max, node;
struct zone *zone;
struct memory_notify arg;
BUG_ON(start_pfn >= end_pfn);
/* at least, alignment against pageblock is necessary */
if (!IS_ALIGNED(start_pfn, pageblock_nr_pages))
return -EINVAL;
if (!IS_ALIGNED(end_pfn, pageblock_nr_pages))
return -EINVAL;
/* This makes hotplug much easier...and readable.
we assume this for now. .*/
if (!test_pages_in_a_zone(start_pfn, end_pfn))
return -EINVAL;
zone = page_zone(pfn_to_page(start_pfn));
node = zone_to_nid(zone);
nr_pages = end_pfn - start_pfn;
/* set above range as isolated */
ret = start_isolate_page_range(start_pfn, end_pfn);
if (ret)
return ret;
arg.start_pfn = start_pfn;
arg.nr_pages = nr_pages;
arg.status_change_nid = -1;
if (nr_pages >= node_present_pages(node))
arg.status_change_nid = node;
ret = memory_notify(MEM_GOING_OFFLINE, &arg);
ret = notifier_to_errno(ret);
if (ret)
goto failed_removal;
pfn = start_pfn;
expire = jiffies + timeout;
drain = 0;
retry_max = 5;
repeat:
/* start memory hot removal */
ret = -EAGAIN;
if (time_after(jiffies, expire))
goto failed_removal;
ret = -EINTR;
if (signal_pending(current))
goto failed_removal;
ret = 0;
if (drain) {
lru_add_drain_all();
flush_scheduled_work();
cond_resched();
drain_all_pages();
}
pfn = scan_lru_pages(start_pfn, end_pfn);
if (pfn) { /* We have page on LRU */
ret = do_migrate_range(pfn, end_pfn);
if (!ret) {
drain = 1;
goto repeat;
} else {
if (ret < 0)
if (--retry_max == 0)
goto failed_removal;
yield();
drain = 1;
goto repeat;
}
}
/* drain all zone's lru pagevec, this is asyncronous... */
lru_add_drain_all();
flush_scheduled_work();
yield();
/* drain pcp pages , this is synchrouns. */
drain_all_pages();
/* check again */
offlined_pages = check_pages_isolated(start_pfn, end_pfn);
if (offlined_pages < 0) {
ret = -EBUSY;
goto failed_removal;
}
printk(KERN_INFO "Offlined Pages %ld\n", offlined_pages);
/* Ok, all of our target is islaoted.
We cannot do rollback at this point. */
offline_isolated_pages(start_pfn, end_pfn);
/* reset pagetype flags and makes migrate type to be MOVABLE */
undo_isolate_page_range(start_pfn, end_pfn);
/* removal success */
zone->present_pages -= offlined_pages;
zone->zone_pgdat->node_present_pages -= offlined_pages;
totalram_pages -= offlined_pages;
num_physpages -= offlined_pages;
vm_total_pages = nr_free_pagecache_pages();
writeback_set_ratelimit();
memory_notify(MEM_OFFLINE, &arg);
return 0;
failed_removal:
printk(KERN_INFO "memory offlining %lx to %lx failed\n",
start_pfn, end_pfn);
memory_notify(MEM_CANCEL_OFFLINE, &arg);
/* pushback to free area */
undo_isolate_page_range(start_pfn, end_pfn);
return ret;
}
#else
int remove_memory(u64 start, u64 size)
{
return -EINVAL;
}
EXPORT_SYMBOL_GPL(remove_memory);
#endif /* CONFIG_MEMORY_HOTREMOVE */