Contributors: 75
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| David Hildenbrand |
1562 |
35.71% |
42 |
24.56% |
| Dave Hansen |
651 |
14.88% |
6 |
3.51% |
| Nathan Fontenot |
339 |
7.75% |
8 |
4.68% |
| Oscar Salvador |
209 |
4.78% |
2 |
1.17% |
| Andi Kleen |
181 |
4.14% |
5 |
2.92% |
| Rafael J. Wysocki |
151 |
3.45% |
3 |
1.75% |
| Naoya Horiguchi |
148 |
3.38% |
3 |
1.75% |
| Michal Hocko |
106 |
2.42% |
4 |
2.34% |
| Seth Jennings |
89 |
2.03% |
6 |
3.51% |
| Scott Cheloha |
76 |
1.74% |
1 |
0.58% |
| Joe Perches |
71 |
1.62% |
2 |
1.17% |
| Kay Sievers |
64 |
1.46% |
3 |
1.75% |
| Zhang Zhen |
56 |
1.28% |
2 |
1.17% |
| Aneesh Kumar K.V |
55 |
1.26% |
1 |
0.58% |
| Vitaly Kuznetsov |
47 |
1.07% |
1 |
0.58% |
| Wen Congyang |
44 |
1.01% |
2 |
1.17% |
| Anton Blanchard |
42 |
0.96% |
2 |
1.17% |
| Yasuaki Ishimatsu |
36 |
0.82% |
3 |
1.75% |
| Reza Arbab |
32 |
0.73% |
2 |
1.17% |
| Badari Pulavarty |
32 |
0.73% |
3 |
1.75% |
| Sumanth Korikkar |
27 |
0.62% |
1 |
0.58% |
| Eric DeVolder |
27 |
0.62% |
1 |
0.58% |
| David Rientjes |
26 |
0.59% |
1 |
0.58% |
| Heiko Carstens |
19 |
0.43% |
1 |
0.58% |
| Mel Gorman |
19 |
0.43% |
1 |
0.58% |
| Andrew Morton |
18 |
0.41% |
2 |
1.17% |
| Fengguang Wu |
18 |
0.41% |
2 |
1.17% |
| Gu Zheng |
17 |
0.39% |
1 |
0.58% |
| Yasunori Goto |
16 |
0.37% |
4 |
2.34% |
| Kamezawa Hiroyuki |
15 |
0.34% |
2 |
1.17% |
| Linus Torvalds |
12 |
0.27% |
4 |
2.34% |
| Arvind Yadav |
12 |
0.27% |
1 |
0.58% |
| luofei |
11 |
0.25% |
1 |
0.58% |
| Yinghai Lu |
10 |
0.23% |
1 |
0.58% |
| Hannes Hering |
10 |
0.23% |
1 |
0.58% |
| Lai Jiangshan |
8 |
0.18% |
1 |
0.58% |
| Linus Torvalds (pre-git) |
8 |
0.18% |
4 |
2.34% |
| Alan Stern |
7 |
0.16% |
1 |
0.58% |
| Nikanth Karthikesan |
7 |
0.16% |
1 |
0.58% |
| Christoph Lameter |
6 |
0.14% |
1 |
0.58% |
| Wei Yang |
6 |
0.14% |
2 |
1.17% |
| Zhang Yanfei |
6 |
0.14% |
1 |
0.58% |
| Anshuman Khandual |
5 |
0.11% |
1 |
0.58% |
| Stephen Rothwell |
4 |
0.09% |
1 |
0.58% |
| 권오훈 |
4 |
0.09% |
1 |
0.58% |
| Nicholas Piggin |
4 |
0.09% |
2 |
1.17% |
| Shaohua Li |
3 |
0.07% |
1 |
0.58% |
| zhong jiang |
3 |
0.07% |
1 |
0.58% |
| Tang Chen |
3 |
0.07% |
1 |
0.58% |
| Toshi Kani |
3 |
0.07% |
1 |
0.58% |
| Thomas Gleixner |
3 |
0.07% |
1 |
0.58% |
| Vivek Goyal |
3 |
0.07% |
1 |
0.58% |
| Rusty Russell |
3 |
0.07% |
1 |
0.58% |
| Arjan van de Ven |
3 |
0.07% |
1 |
0.58% |
| John Allen |
3 |
0.07% |
1 |
0.58% |
| Laurent Dufour |
3 |
0.07% |
1 |
0.58% |
| Randy Dunlap |
2 |
0.05% |
1 |
0.58% |
| Harvey Harrison |
2 |
0.05% |
1 |
0.58% |
| Peter Xu |
2 |
0.05% |
1 |
0.58% |
| Pavel Tatashin |
2 |
0.05% |
2 |
1.17% |
| Baoquan He |
2 |
0.05% |
1 |
0.58% |
| Gavin Shan |
2 |
0.05% |
1 |
0.58% |
| Robert Jennings |
2 |
0.05% |
1 |
0.58% |
| Rikard Falkeborn |
2 |
0.05% |
1 |
0.58% |
| Jingoo Han |
2 |
0.05% |
1 |
0.58% |
| Matthew Dobson |
2 |
0.05% |
1 |
0.58% |
| Ben Dooks |
2 |
0.05% |
1 |
0.58% |
| Michel Lespinasse |
2 |
0.05% |
1 |
0.58% |
| Konrad Rzeszutek Wilk |
1 |
0.02% |
1 |
0.58% |
| Greg Kroah-Hartman |
1 |
0.02% |
1 |
0.58% |
| Tony Luck |
1 |
0.02% |
1 |
0.58% |
| zhenwei.pi |
1 |
0.02% |
1 |
0.58% |
| Michael Holzheu |
1 |
0.02% |
1 |
0.58% |
| Arun Sharma |
1 |
0.02% |
1 |
0.58% |
| Cody P Schafer |
1 |
0.02% |
1 |
0.58% |
| Total |
4374 |
|
171 |
|
// SPDX-License-Identifier: GPL-2.0
/*
* Memory subsystem support
*
* Written by Matt Tolentino <matthew.e.tolentino@intel.com>
* Dave Hansen <haveblue@us.ibm.com>
*
* This file provides the necessary infrastructure to represent
* a SPARSEMEM-memory-model system's physical memory in /sysfs.
* All arch-independent code that assumes MEMORY_HOTPLUG requires
* SPARSEMEM should be contained here, or in mm/memory_hotplug.c.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/topology.h>
#include <linux/capability.h>
#include <linux/device.h>
#include <linux/memory.h>
#include <linux/memory_hotplug.h>
#include <linux/mm.h>
#include <linux/stat.h>
#include <linux/slab.h>
#include <linux/xarray.h>
#include <linux/atomic.h>
#include <linux/uaccess.h>
#define MEMORY_CLASS_NAME "memory"
static const char *const online_type_to_str[] = {
[MMOP_OFFLINE] = "offline",
[MMOP_ONLINE] = "online",
[MMOP_ONLINE_KERNEL] = "online_kernel",
[MMOP_ONLINE_MOVABLE] = "online_movable",
};
int mhp_online_type_from_str(const char *str)
{
int i;
for (i = 0; i < ARRAY_SIZE(online_type_to_str); i++) {
if (sysfs_streq(str, online_type_to_str[i]))
return i;
}
return -EINVAL;
}
#define to_memory_block(dev) container_of(dev, struct memory_block, dev)
static int sections_per_block;
static inline unsigned long memory_block_id(unsigned long section_nr)
{
return section_nr / sections_per_block;
}
static inline unsigned long pfn_to_block_id(unsigned long pfn)
{
return memory_block_id(pfn_to_section_nr(pfn));
}
static inline unsigned long phys_to_block_id(unsigned long phys)
{
return pfn_to_block_id(PFN_DOWN(phys));
}
static int memory_subsys_online(struct device *dev);
static int memory_subsys_offline(struct device *dev);
static struct bus_type memory_subsys = {
.name = MEMORY_CLASS_NAME,
.dev_name = MEMORY_CLASS_NAME,
.online = memory_subsys_online,
.offline = memory_subsys_offline,
};
/*
* Memory blocks are cached in a local radix tree to avoid
* a costly linear search for the corresponding device on
* the subsystem bus.
*/
static DEFINE_XARRAY(memory_blocks);
/*
* Memory groups, indexed by memory group id (mgid).
*/
static DEFINE_XARRAY_FLAGS(memory_groups, XA_FLAGS_ALLOC);
#define MEMORY_GROUP_MARK_DYNAMIC XA_MARK_1
static BLOCKING_NOTIFIER_HEAD(memory_chain);
int register_memory_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_register(&memory_chain, nb);
}
EXPORT_SYMBOL(register_memory_notifier);
void unregister_memory_notifier(struct notifier_block *nb)
{
blocking_notifier_chain_unregister(&memory_chain, nb);
}
EXPORT_SYMBOL(unregister_memory_notifier);
static void memory_block_release(struct device *dev)
{
struct memory_block *mem = to_memory_block(dev);
/* Verify that the altmap is freed */
WARN_ON(mem->altmap);
kfree(mem);
}
unsigned long __weak memory_block_size_bytes(void)
{
return MIN_MEMORY_BLOCK_SIZE;
}
EXPORT_SYMBOL_GPL(memory_block_size_bytes);
/* Show the memory block ID, relative to the memory block size */
static ssize_t phys_index_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct memory_block *mem = to_memory_block(dev);
return sysfs_emit(buf, "%08lx\n", memory_block_id(mem->start_section_nr));
}
/*
* Legacy interface that we cannot remove. Always indicate "removable"
* with CONFIG_MEMORY_HOTREMOVE - bad heuristic.
*/
static ssize_t removable_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
return sysfs_emit(buf, "%d\n", (int)IS_ENABLED(CONFIG_MEMORY_HOTREMOVE));
}
/*
* online, offline, going offline, etc.
*/
static ssize_t state_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct memory_block *mem = to_memory_block(dev);
const char *output;
/*
* We can probably put these states in a nice little array
* so that they're not open-coded
*/
switch (mem->state) {
case MEM_ONLINE:
output = "online";
break;
case MEM_OFFLINE:
output = "offline";
break;
case MEM_GOING_OFFLINE:
output = "going-offline";
break;
default:
WARN_ON(1);
return sysfs_emit(buf, "ERROR-UNKNOWN-%ld\n", mem->state);
}
return sysfs_emit(buf, "%s\n", output);
}
int memory_notify(unsigned long val, void *v)
{
return blocking_notifier_call_chain(&memory_chain, val, v);
}
#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG)
static unsigned long memblk_nr_poison(struct memory_block *mem);
#else
static inline unsigned long memblk_nr_poison(struct memory_block *mem)
{
return 0;
}
#endif
/*
* Must acquire mem_hotplug_lock in write mode.
*/
static int memory_block_online(struct memory_block *mem)
{
unsigned long start_pfn = section_nr_to_pfn(mem->start_section_nr);
unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
unsigned long nr_vmemmap_pages = 0;
struct zone *zone;
int ret;
if (memblk_nr_poison(mem))
return -EHWPOISON;
zone = zone_for_pfn_range(mem->online_type, mem->nid, mem->group,
start_pfn, nr_pages);
/*
* Although vmemmap pages have a different lifecycle than the pages
* they describe (they remain until the memory is unplugged), doing
* their initialization and accounting at memory onlining/offlining
* stage helps to keep accounting easier to follow - e.g vmemmaps
* belong to the same zone as the memory they backed.
*/
if (mem->altmap)
nr_vmemmap_pages = mem->altmap->free;
mem_hotplug_begin();
if (nr_vmemmap_pages) {
ret = mhp_init_memmap_on_memory(start_pfn, nr_vmemmap_pages, zone);
if (ret)
goto out;
}
ret = online_pages(start_pfn + nr_vmemmap_pages,
nr_pages - nr_vmemmap_pages, zone, mem->group);
if (ret) {
if (nr_vmemmap_pages)
mhp_deinit_memmap_on_memory(start_pfn, nr_vmemmap_pages);
goto out;
}
/*
* Account once onlining succeeded. If the zone was unpopulated, it is
* now already properly populated.
*/
if (nr_vmemmap_pages)
adjust_present_page_count(pfn_to_page(start_pfn), mem->group,
nr_vmemmap_pages);
mem->zone = zone;
out:
mem_hotplug_done();
return ret;
}
/*
* Must acquire mem_hotplug_lock in write mode.
*/
static int memory_block_offline(struct memory_block *mem)
{
unsigned long start_pfn = section_nr_to_pfn(mem->start_section_nr);
unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
unsigned long nr_vmemmap_pages = 0;
int ret;
if (!mem->zone)
return -EINVAL;
/*
* Unaccount before offlining, such that unpopulated zone and kthreads
* can properly be torn down in offline_pages().
*/
if (mem->altmap)
nr_vmemmap_pages = mem->altmap->free;
mem_hotplug_begin();
if (nr_vmemmap_pages)
adjust_present_page_count(pfn_to_page(start_pfn), mem->group,
-nr_vmemmap_pages);
ret = offline_pages(start_pfn + nr_vmemmap_pages,
nr_pages - nr_vmemmap_pages, mem->zone, mem->group);
if (ret) {
/* offline_pages() failed. Account back. */
if (nr_vmemmap_pages)
adjust_present_page_count(pfn_to_page(start_pfn),
mem->group, nr_vmemmap_pages);
goto out;
}
if (nr_vmemmap_pages)
mhp_deinit_memmap_on_memory(start_pfn, nr_vmemmap_pages);
mem->zone = NULL;
out:
mem_hotplug_done();
return ret;
}
/*
* MEMORY_HOTPLUG depends on SPARSEMEM in mm/Kconfig, so it is
* OK to have direct references to sparsemem variables in here.
*/
static int
memory_block_action(struct memory_block *mem, unsigned long action)
{
int ret;
switch (action) {
case MEM_ONLINE:
ret = memory_block_online(mem);
break;
case MEM_OFFLINE:
ret = memory_block_offline(mem);
break;
default:
WARN(1, KERN_WARNING "%s(%ld, %ld) unknown action: "
"%ld\n", __func__, mem->start_section_nr, action, action);
ret = -EINVAL;
}
return ret;
}
static int memory_block_change_state(struct memory_block *mem,
unsigned long to_state, unsigned long from_state_req)
{
int ret = 0;
if (mem->state != from_state_req)
return -EINVAL;
if (to_state == MEM_OFFLINE)
mem->state = MEM_GOING_OFFLINE;
ret = memory_block_action(mem, to_state);
mem->state = ret ? from_state_req : to_state;
return ret;
}
/* The device lock serializes operations on memory_subsys_[online|offline] */
static int memory_subsys_online(struct device *dev)
{
struct memory_block *mem = to_memory_block(dev);
int ret;
if (mem->state == MEM_ONLINE)
return 0;
/*
* When called via device_online() without configuring the online_type,
* we want to default to MMOP_ONLINE.
*/
if (mem->online_type == MMOP_OFFLINE)
mem->online_type = MMOP_ONLINE;
ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
mem->online_type = MMOP_OFFLINE;
return ret;
}
static int memory_subsys_offline(struct device *dev)
{
struct memory_block *mem = to_memory_block(dev);
if (mem->state == MEM_OFFLINE)
return 0;
return memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE);
}
static ssize_t state_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
const int online_type = mhp_online_type_from_str(buf);
struct memory_block *mem = to_memory_block(dev);
int ret;
if (online_type < 0)
return -EINVAL;
ret = lock_device_hotplug_sysfs();
if (ret)
return ret;
switch (online_type) {
case MMOP_ONLINE_KERNEL:
case MMOP_ONLINE_MOVABLE:
case MMOP_ONLINE:
/* mem->online_type is protected by device_hotplug_lock */
mem->online_type = online_type;
ret = device_online(&mem->dev);
break;
case MMOP_OFFLINE:
ret = device_offline(&mem->dev);
break;
default:
ret = -EINVAL; /* should never happen */
}
unlock_device_hotplug();
if (ret < 0)
return ret;
if (ret)
return -EINVAL;
return count;
}
/*
* Legacy interface that we cannot remove: s390x exposes the storage increment
* covered by a memory block, allowing for identifying which memory blocks
* comprise a storage increment. Since a memory block spans complete
* storage increments nowadays, this interface is basically unused. Other
* archs never exposed != 0.
*/
static ssize_t phys_device_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct memory_block *mem = to_memory_block(dev);
unsigned long start_pfn = section_nr_to_pfn(mem->start_section_nr);
return sysfs_emit(buf, "%d\n",
arch_get_memory_phys_device(start_pfn));
}
#ifdef CONFIG_MEMORY_HOTREMOVE
static int print_allowed_zone(char *buf, int len, int nid,
struct memory_group *group,
unsigned long start_pfn, unsigned long nr_pages,
int online_type, struct zone *default_zone)
{
struct zone *zone;
zone = zone_for_pfn_range(online_type, nid, group, start_pfn, nr_pages);
if (zone == default_zone)
return 0;
return sysfs_emit_at(buf, len, " %s", zone->name);
}
static ssize_t valid_zones_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct memory_block *mem = to_memory_block(dev);
unsigned long start_pfn = section_nr_to_pfn(mem->start_section_nr);
unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
struct memory_group *group = mem->group;
struct zone *default_zone;
int nid = mem->nid;
int len = 0;
/*
* Check the existing zone. Make sure that we do that only on the
* online nodes otherwise the page_zone is not reliable
*/
if (mem->state == MEM_ONLINE) {
/*
* If !mem->zone, the memory block spans multiple zones and
* cannot get offlined.
*/
default_zone = mem->zone;
if (!default_zone)
return sysfs_emit(buf, "%s\n", "none");
len += sysfs_emit_at(buf, len, "%s", default_zone->name);
goto out;
}
default_zone = zone_for_pfn_range(MMOP_ONLINE, nid, group,
start_pfn, nr_pages);
len += sysfs_emit_at(buf, len, "%s", default_zone->name);
len += print_allowed_zone(buf, len, nid, group, start_pfn, nr_pages,
MMOP_ONLINE_KERNEL, default_zone);
len += print_allowed_zone(buf, len, nid, group, start_pfn, nr_pages,
MMOP_ONLINE_MOVABLE, default_zone);
out:
len += sysfs_emit_at(buf, len, "\n");
return len;
}
static DEVICE_ATTR_RO(valid_zones);
#endif
static DEVICE_ATTR_RO(phys_index);
static DEVICE_ATTR_RW(state);
static DEVICE_ATTR_RO(phys_device);
static DEVICE_ATTR_RO(removable);
/*
* Show the memory block size (shared by all memory blocks).
*/
static ssize_t block_size_bytes_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sysfs_emit(buf, "%lx\n", memory_block_size_bytes());
}
static DEVICE_ATTR_RO(block_size_bytes);
/*
* Memory auto online policy.
*/
static ssize_t auto_online_blocks_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sysfs_emit(buf, "%s\n",
online_type_to_str[mhp_default_online_type]);
}
static ssize_t auto_online_blocks_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
const int online_type = mhp_online_type_from_str(buf);
if (online_type < 0)
return -EINVAL;
mhp_default_online_type = online_type;
return count;
}
static DEVICE_ATTR_RW(auto_online_blocks);
#ifdef CONFIG_CRASH_HOTPLUG
#include <linux/kexec.h>
static ssize_t crash_hotplug_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sysfs_emit(buf, "%d\n", crash_hotplug_memory_support());
}
static DEVICE_ATTR_RO(crash_hotplug);
#endif
/*
* Some architectures will have custom drivers to do this, and
* will not need to do it from userspace. The fake hot-add code
* as well as ppc64 will do all of their discovery in userspace
* and will require this interface.
*/
#ifdef CONFIG_ARCH_MEMORY_PROBE
static ssize_t probe_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
u64 phys_addr;
int nid, ret;
unsigned long pages_per_block = PAGES_PER_SECTION * sections_per_block;
ret = kstrtoull(buf, 0, &phys_addr);
if (ret)
return ret;
if (phys_addr & ((pages_per_block << PAGE_SHIFT) - 1))
return -EINVAL;
ret = lock_device_hotplug_sysfs();
if (ret)
return ret;
nid = memory_add_physaddr_to_nid(phys_addr);
ret = __add_memory(nid, phys_addr,
MIN_MEMORY_BLOCK_SIZE * sections_per_block,
MHP_NONE);
if (ret)
goto out;
ret = count;
out:
unlock_device_hotplug();
return ret;
}
static DEVICE_ATTR_WO(probe);
#endif
#ifdef CONFIG_MEMORY_FAILURE
/*
* Support for offlining pages of memory
*/
/* Soft offline a page */
static ssize_t soft_offline_page_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
int ret;
u64 pfn;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (kstrtoull(buf, 0, &pfn) < 0)
return -EINVAL;
pfn >>= PAGE_SHIFT;
ret = soft_offline_page(pfn, 0);
return ret == 0 ? count : ret;
}
/* Forcibly offline a page, including killing processes. */
static ssize_t hard_offline_page_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
int ret;
u64 pfn;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (kstrtoull(buf, 0, &pfn) < 0)
return -EINVAL;
pfn >>= PAGE_SHIFT;
ret = memory_failure(pfn, MF_SW_SIMULATED);
if (ret == -EOPNOTSUPP)
ret = 0;
return ret ? ret : count;
}
static DEVICE_ATTR_WO(soft_offline_page);
static DEVICE_ATTR_WO(hard_offline_page);
#endif
/* See phys_device_show(). */
int __weak arch_get_memory_phys_device(unsigned long start_pfn)
{
return 0;
}
/*
* A reference for the returned memory block device is acquired.
*
* Called under device_hotplug_lock.
*/
static struct memory_block *find_memory_block_by_id(unsigned long block_id)
{
struct memory_block *mem;
mem = xa_load(&memory_blocks, block_id);
if (mem)
get_device(&mem->dev);
return mem;
}
/*
* Called under device_hotplug_lock.
*/
struct memory_block *find_memory_block(unsigned long section_nr)
{
unsigned long block_id = memory_block_id(section_nr);
return find_memory_block_by_id(block_id);
}
static struct attribute *memory_memblk_attrs[] = {
&dev_attr_phys_index.attr,
&dev_attr_state.attr,
&dev_attr_phys_device.attr,
&dev_attr_removable.attr,
#ifdef CONFIG_MEMORY_HOTREMOVE
&dev_attr_valid_zones.attr,
#endif
NULL
};
static const struct attribute_group memory_memblk_attr_group = {
.attrs = memory_memblk_attrs,
};
static const struct attribute_group *memory_memblk_attr_groups[] = {
&memory_memblk_attr_group,
NULL,
};
static int __add_memory_block(struct memory_block *memory)
{
int ret;
memory->dev.bus = &memory_subsys;
memory->dev.id = memory->start_section_nr / sections_per_block;
memory->dev.release = memory_block_release;
memory->dev.groups = memory_memblk_attr_groups;
memory->dev.offline = memory->state == MEM_OFFLINE;
ret = device_register(&memory->dev);
if (ret) {
put_device(&memory->dev);
return ret;
}
ret = xa_err(xa_store(&memory_blocks, memory->dev.id, memory,
GFP_KERNEL));
if (ret)
device_unregister(&memory->dev);
return ret;
}
static struct zone *early_node_zone_for_memory_block(struct memory_block *mem,
int nid)
{
const unsigned long start_pfn = section_nr_to_pfn(mem->start_section_nr);
const unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
struct zone *zone, *matching_zone = NULL;
pg_data_t *pgdat = NODE_DATA(nid);
int i;
/*
* This logic only works for early memory, when the applicable zones
* already span the memory block. We don't expect overlapping zones on
* a single node for early memory. So if we're told that some PFNs
* of a node fall into this memory block, we can assume that all node
* zones that intersect with the memory block are actually applicable.
* No need to look at the memmap.
*/
for (i = 0; i < MAX_NR_ZONES; i++) {
zone = pgdat->node_zones + i;
if (!populated_zone(zone))
continue;
if (!zone_intersects(zone, start_pfn, nr_pages))
continue;
if (!matching_zone) {
matching_zone = zone;
continue;
}
/* Spans multiple zones ... */
matching_zone = NULL;
break;
}
return matching_zone;
}
#ifdef CONFIG_NUMA
/**
* memory_block_add_nid() - Indicate that system RAM falling into this memory
* block device (partially) belongs to the given node.
* @mem: The memory block device.
* @nid: The node id.
* @context: The memory initialization context.
*
* Indicate that system RAM falling into this memory block (partially) belongs
* to the given node. If the context indicates ("early") that we are adding the
* node during node device subsystem initialization, this will also properly
* set/adjust mem->zone based on the zone ranges of the given node.
*/
void memory_block_add_nid(struct memory_block *mem, int nid,
enum meminit_context context)
{
if (context == MEMINIT_EARLY && mem->nid != nid) {
/*
* For early memory we have to determine the zone when setting
* the node id and handle multiple nodes spanning a single
* memory block by indicate via zone == NULL that we're not
* dealing with a single zone. So if we're setting the node id
* the first time, determine if there is a single zone. If we're
* setting the node id a second time to a different node,
* invalidate the single detected zone.
*/
if (mem->nid == NUMA_NO_NODE)
mem->zone = early_node_zone_for_memory_block(mem, nid);
else
mem->zone = NULL;
}
/*
* If this memory block spans multiple nodes, we only indicate
* the last processed node. If we span multiple nodes (not applicable
* to hotplugged memory), zone == NULL will prohibit memory offlining
* and consequently unplug.
*/
mem->nid = nid;
}
#endif
static int add_memory_block(unsigned long block_id, unsigned long state,
struct vmem_altmap *altmap,
struct memory_group *group)
{
struct memory_block *mem;
int ret = 0;
mem = find_memory_block_by_id(block_id);
if (mem) {
put_device(&mem->dev);
return -EEXIST;
}
mem = kzalloc(sizeof(*mem), GFP_KERNEL);
if (!mem)
return -ENOMEM;
mem->start_section_nr = block_id * sections_per_block;
mem->state = state;
mem->nid = NUMA_NO_NODE;
mem->altmap = altmap;
INIT_LIST_HEAD(&mem->group_next);
#ifndef CONFIG_NUMA
if (state == MEM_ONLINE)
/*
* MEM_ONLINE at this point implies early memory. With NUMA,
* we'll determine the zone when setting the node id via
* memory_block_add_nid(). Memory hotplug updated the zone
* manually when memory onlining/offlining succeeds.
*/
mem->zone = early_node_zone_for_memory_block(mem, NUMA_NO_NODE);
#endif /* CONFIG_NUMA */
ret = __add_memory_block(mem);
if (ret)
return ret;
if (group) {
mem->group = group;
list_add(&mem->group_next, &group->memory_blocks);
}
return 0;
}
static int __init add_boot_memory_block(unsigned long base_section_nr)
{
int section_count = 0;
unsigned long nr;
for (nr = base_section_nr; nr < base_section_nr + sections_per_block;
nr++)
if (present_section_nr(nr))
section_count++;
if (section_count == 0)
return 0;
return add_memory_block(memory_block_id(base_section_nr),
MEM_ONLINE, NULL, NULL);
}
static int add_hotplug_memory_block(unsigned long block_id,
struct vmem_altmap *altmap,
struct memory_group *group)
{
return add_memory_block(block_id, MEM_OFFLINE, altmap, group);
}
static void remove_memory_block(struct memory_block *memory)
{
if (WARN_ON_ONCE(memory->dev.bus != &memory_subsys))
return;
WARN_ON(xa_erase(&memory_blocks, memory->dev.id) == NULL);
if (memory->group) {
list_del(&memory->group_next);
memory->group = NULL;
}
/* drop the ref. we got via find_memory_block() */
put_device(&memory->dev);
device_unregister(&memory->dev);
}
/*
* Create memory block devices for the given memory area. Start and size
* have to be aligned to memory block granularity. Memory block devices
* will be initialized as offline.
*
* Called under device_hotplug_lock.
*/
int create_memory_block_devices(unsigned long start, unsigned long size,
struct vmem_altmap *altmap,
struct memory_group *group)
{
const unsigned long start_block_id = pfn_to_block_id(PFN_DOWN(start));
unsigned long end_block_id = pfn_to_block_id(PFN_DOWN(start + size));
struct memory_block *mem;
unsigned long block_id;
int ret = 0;
if (WARN_ON_ONCE(!IS_ALIGNED(start, memory_block_size_bytes()) ||
!IS_ALIGNED(size, memory_block_size_bytes())))
return -EINVAL;
for (block_id = start_block_id; block_id != end_block_id; block_id++) {
ret = add_hotplug_memory_block(block_id, altmap, group);
if (ret)
break;
}
if (ret) {
end_block_id = block_id;
for (block_id = start_block_id; block_id != end_block_id;
block_id++) {
mem = find_memory_block_by_id(block_id);
if (WARN_ON_ONCE(!mem))
continue;
remove_memory_block(mem);
}
}
return ret;
}
/*
* Remove memory block devices for the given memory area. Start and size
* have to be aligned to memory block granularity. Memory block devices
* have to be offline.
*
* Called under device_hotplug_lock.
*/
void remove_memory_block_devices(unsigned long start, unsigned long size)
{
const unsigned long start_block_id = pfn_to_block_id(PFN_DOWN(start));
const unsigned long end_block_id = pfn_to_block_id(PFN_DOWN(start + size));
struct memory_block *mem;
unsigned long block_id;
if (WARN_ON_ONCE(!IS_ALIGNED(start, memory_block_size_bytes()) ||
!IS_ALIGNED(size, memory_block_size_bytes())))
return;
for (block_id = start_block_id; block_id != end_block_id; block_id++) {
mem = find_memory_block_by_id(block_id);
if (WARN_ON_ONCE(!mem))
continue;
num_poisoned_pages_sub(-1UL, memblk_nr_poison(mem));
unregister_memory_block_under_nodes(mem);
remove_memory_block(mem);
}
}
static struct attribute *memory_root_attrs[] = {
#ifdef CONFIG_ARCH_MEMORY_PROBE
&dev_attr_probe.attr,
#endif
#ifdef CONFIG_MEMORY_FAILURE
&dev_attr_soft_offline_page.attr,
&dev_attr_hard_offline_page.attr,
#endif
&dev_attr_block_size_bytes.attr,
&dev_attr_auto_online_blocks.attr,
#ifdef CONFIG_CRASH_HOTPLUG
&dev_attr_crash_hotplug.attr,
#endif
NULL
};
static const struct attribute_group memory_root_attr_group = {
.attrs = memory_root_attrs,
};
static const struct attribute_group *memory_root_attr_groups[] = {
&memory_root_attr_group,
NULL,
};
/*
* Initialize the sysfs support for memory devices. At the time this function
* is called, we cannot have concurrent creation/deletion of memory block
* devices, the device_hotplug_lock is not needed.
*/
void __init memory_dev_init(void)
{
int ret;
unsigned long block_sz, nr;
/* Validate the configured memory block size */
block_sz = memory_block_size_bytes();
if (!is_power_of_2(block_sz) || block_sz < MIN_MEMORY_BLOCK_SIZE)
panic("Memory block size not suitable: 0x%lx\n", block_sz);
sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
ret = subsys_system_register(&memory_subsys, memory_root_attr_groups);
if (ret)
panic("%s() failed to register subsystem: %d\n", __func__, ret);
/*
* Create entries for memory sections that were found
* during boot and have been initialized
*/
for (nr = 0; nr <= __highest_present_section_nr;
nr += sections_per_block) {
ret = add_boot_memory_block(nr);
if (ret)
panic("%s() failed to add memory block: %d\n", __func__,
ret);
}
}
/**
* walk_memory_blocks - walk through all present memory blocks overlapped
* by the range [start, start + size)
*
* @start: start address of the memory range
* @size: size of the memory range
* @arg: argument passed to func
* @func: callback for each memory section walked
*
* This function walks through all present memory blocks overlapped by the
* range [start, start + size), calling func on each memory block.
*
* In case func() returns an error, walking is aborted and the error is
* returned.
*
* Called under device_hotplug_lock.
*/
int walk_memory_blocks(unsigned long start, unsigned long size,
void *arg, walk_memory_blocks_func_t func)
{
const unsigned long start_block_id = phys_to_block_id(start);
const unsigned long end_block_id = phys_to_block_id(start + size - 1);
struct memory_block *mem;
unsigned long block_id;
int ret = 0;
if (!size)
return 0;
for (block_id = start_block_id; block_id <= end_block_id; block_id++) {
mem = find_memory_block_by_id(block_id);
if (!mem)
continue;
ret = func(mem, arg);
put_device(&mem->dev);
if (ret)
break;
}
return ret;
}
struct for_each_memory_block_cb_data {
walk_memory_blocks_func_t func;
void *arg;
};
static int for_each_memory_block_cb(struct device *dev, void *data)
{
struct memory_block *mem = to_memory_block(dev);
struct for_each_memory_block_cb_data *cb_data = data;
return cb_data->func(mem, cb_data->arg);
}
/**
* for_each_memory_block - walk through all present memory blocks
*
* @arg: argument passed to func
* @func: callback for each memory block walked
*
* This function walks through all present memory blocks, calling func on
* each memory block.
*
* In case func() returns an error, walking is aborted and the error is
* returned.
*/
int for_each_memory_block(void *arg, walk_memory_blocks_func_t func)
{
struct for_each_memory_block_cb_data cb_data = {
.func = func,
.arg = arg,
};
return bus_for_each_dev(&memory_subsys, NULL, &cb_data,
for_each_memory_block_cb);
}
/*
* This is an internal helper to unify allocation and initialization of
* memory groups. Note that the passed memory group will be copied to a
* dynamically allocated memory group. After this call, the passed
* memory group should no longer be used.
*/
static int memory_group_register(struct memory_group group)
{
struct memory_group *new_group;
uint32_t mgid;
int ret;
if (!node_possible(group.nid))
return -EINVAL;
new_group = kzalloc(sizeof(group), GFP_KERNEL);
if (!new_group)
return -ENOMEM;
*new_group = group;
INIT_LIST_HEAD(&new_group->memory_blocks);
ret = xa_alloc(&memory_groups, &mgid, new_group, xa_limit_31b,
GFP_KERNEL);
if (ret) {
kfree(new_group);
return ret;
} else if (group.is_dynamic) {
xa_set_mark(&memory_groups, mgid, MEMORY_GROUP_MARK_DYNAMIC);
}
return mgid;
}
/**
* memory_group_register_static() - Register a static memory group.
* @nid: The node id.
* @max_pages: The maximum number of pages we'll have in this static memory
* group.
*
* Register a new static memory group and return the memory group id.
* All memory in the group belongs to a single unit, such as a DIMM. All
* memory belonging to a static memory group is added in one go to be removed
* in one go -- it's static.
*
* Returns an error if out of memory, if the node id is invalid, if no new
* memory groups can be registered, or if max_pages is invalid (0). Otherwise,
* returns the new memory group id.
*/
int memory_group_register_static(int nid, unsigned long max_pages)
{
struct memory_group group = {
.nid = nid,
.s = {
.max_pages = max_pages,
},
};
if (!max_pages)
return -EINVAL;
return memory_group_register(group);
}
EXPORT_SYMBOL_GPL(memory_group_register_static);
/**
* memory_group_register_dynamic() - Register a dynamic memory group.
* @nid: The node id.
* @unit_pages: Unit in pages in which is memory added/removed in this dynamic
* memory group.
*
* Register a new dynamic memory group and return the memory group id.
* Memory within a dynamic memory group is added/removed dynamically
* in unit_pages.
*
* Returns an error if out of memory, if the node id is invalid, if no new
* memory groups can be registered, or if unit_pages is invalid (0, not a
* power of two, smaller than a single memory block). Otherwise, returns the
* new memory group id.
*/
int memory_group_register_dynamic(int nid, unsigned long unit_pages)
{
struct memory_group group = {
.nid = nid,
.is_dynamic = true,
.d = {
.unit_pages = unit_pages,
},
};
if (!unit_pages || !is_power_of_2(unit_pages) ||
unit_pages < PHYS_PFN(memory_block_size_bytes()))
return -EINVAL;
return memory_group_register(group);
}
EXPORT_SYMBOL_GPL(memory_group_register_dynamic);
/**
* memory_group_unregister() - Unregister a memory group.
* @mgid: the memory group id
*
* Unregister a memory group. If any memory block still belongs to this
* memory group, unregistering will fail.
*
* Returns -EINVAL if the memory group id is invalid, returns -EBUSY if some
* memory blocks still belong to this memory group and returns 0 if
* unregistering succeeded.
*/
int memory_group_unregister(int mgid)
{
struct memory_group *group;
if (mgid < 0)
return -EINVAL;
group = xa_load(&memory_groups, mgid);
if (!group)
return -EINVAL;
if (!list_empty(&group->memory_blocks))
return -EBUSY;
xa_erase(&memory_groups, mgid);
kfree(group);
return 0;
}
EXPORT_SYMBOL_GPL(memory_group_unregister);
/*
* This is an internal helper only to be used in core memory hotplug code to
* lookup a memory group. We don't care about locking, as we don't expect a
* memory group to get unregistered while adding memory to it -- because
* the group and the memory is managed by the same driver.
*/
struct memory_group *memory_group_find_by_id(int mgid)
{
return xa_load(&memory_groups, mgid);
}
/*
* This is an internal helper only to be used in core memory hotplug code to
* walk all dynamic memory groups excluding a given memory group, either
* belonging to a specific node, or belonging to any node.
*/
int walk_dynamic_memory_groups(int nid, walk_memory_groups_func_t func,
struct memory_group *excluded, void *arg)
{
struct memory_group *group;
unsigned long index;
int ret = 0;
xa_for_each_marked(&memory_groups, index, group,
MEMORY_GROUP_MARK_DYNAMIC) {
if (group == excluded)
continue;
#ifdef CONFIG_NUMA
if (nid != NUMA_NO_NODE && group->nid != nid)
continue;
#endif /* CONFIG_NUMA */
ret = func(group, arg);
if (ret)
break;
}
return ret;
}
#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG)
void memblk_nr_poison_inc(unsigned long pfn)
{
const unsigned long block_id = pfn_to_block_id(pfn);
struct memory_block *mem = find_memory_block_by_id(block_id);
if (mem)
atomic_long_inc(&mem->nr_hwpoison);
}
void memblk_nr_poison_sub(unsigned long pfn, long i)
{
const unsigned long block_id = pfn_to_block_id(pfn);
struct memory_block *mem = find_memory_block_by_id(block_id);
if (mem)
atomic_long_sub(i, &mem->nr_hwpoison);
}
static unsigned long memblk_nr_poison(struct memory_block *mem)
{
return atomic_long_read(&mem->nr_hwpoison);
}
#endif