summaryrefslogtreecommitdiff
path: root/drivers/base/memory.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/base/memory.c')
-rw-r--r--drivers/base/memory.c1325
1 files changed, 905 insertions, 420 deletions
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 2b7813ec6d02..751f248ca4a8 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
/*
* Memory subsystem support
*
@@ -16,215 +17,305 @@
#include <linux/capability.h>
#include <linux/device.h>
#include <linux/memory.h>
-#include <linux/kobject.h>
#include <linux/memory_hotplug.h>
#include <linux/mm.h>
-#include <linux/mutex.h>
#include <linux/stat.h>
#include <linux/slab.h>
+#include <linux/xarray.h>
+#include <linux/export.h>
#include <linux/atomic.h>
-#include <asm/uaccess.h>
-
-static DEFINE_MUTEX(mem_sysfs_mutex);
+#include <linux/uaccess.h>
#define MEMORY_CLASS_NAME "memory"
-static int sections_per_block;
+static const char *const online_type_to_str[] = {
+ [MMOP_OFFLINE] = "offline",
+ [MMOP_ONLINE] = "online",
+ [MMOP_ONLINE_KERNEL] = "online_kernel",
+ [MMOP_ONLINE_MOVABLE] = "online_movable",
+};
-static inline int base_memory_block_id(int section_nr)
+int mhp_online_type_from_str(const char *str)
{
- return section_nr / sections_per_block;
+ 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)
+
+int sections_per_block;
+EXPORT_SYMBOL(sections_per_block);
+
static int memory_subsys_online(struct device *dev);
static int memory_subsys_offline(struct device *dev);
-static struct bus_type memory_subsys = {
+static const 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);
+ 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);
+ blocking_notifier_chain_unregister(&memory_chain, nb);
}
EXPORT_SYMBOL(unregister_memory_notifier);
-static ATOMIC_NOTIFIER_HEAD(memory_isolate_chain);
-
-int register_memory_isolate_notifier(struct notifier_block *nb)
-{
- return atomic_notifier_chain_register(&memory_isolate_chain, nb);
-}
-EXPORT_SYMBOL(register_memory_isolate_notifier);
-
-void unregister_memory_isolate_notifier(struct notifier_block *nb)
-{
- atomic_notifier_chain_unregister(&memory_isolate_chain, nb);
-}
-EXPORT_SYMBOL(unregister_memory_isolate_notifier);
-
static void memory_block_release(struct device *dev)
{
- struct memory_block *mem = container_of(dev, struct memory_block, 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;
-}
-static unsigned long get_memory_block_size(void)
+/* Max block size to be set by memory_block_advise_max_size */
+static unsigned long memory_block_advised_size;
+static bool memory_block_advised_size_queried;
+
+/**
+ * memory_block_advise_max_size() - advise memory hotplug on the max suggested
+ * block size, usually for alignment.
+ * @size: suggestion for maximum block size. must be aligned on power of 2.
+ *
+ * Early boot software (pre-allocator init) may advise archs on the max block
+ * size. This value can only decrease after initialization, as the intent is
+ * to identify the largest supported alignment for all sources.
+ *
+ * Use of this value is arch-defined, as is min/max block size.
+ *
+ * Return: 0 on success
+ * -EINVAL if size is 0 or not pow2 aligned
+ * -EBUSY if value has already been probed
+ */
+int __init memory_block_advise_max_size(unsigned long size)
{
- unsigned long block_sz;
+ if (!size || !is_power_of_2(size))
+ return -EINVAL;
- block_sz = memory_block_size_bytes();
+ if (memory_block_advised_size_queried)
+ return -EBUSY;
- /* Validate blk_sz is a power of 2 and not less than section size */
- if ((block_sz & (block_sz - 1)) || (block_sz < MIN_MEMORY_BLOCK_SIZE)) {
- WARN_ON(1);
- block_sz = MIN_MEMORY_BLOCK_SIZE;
- }
+ if (memory_block_advised_size)
+ memory_block_advised_size = min(memory_block_advised_size, size);
+ else
+ memory_block_advised_size = size;
- return block_sz;
+ return 0;
}
-/*
- * use this as the physical section index that this memsection
- * uses.
+/**
+ * memory_block_advised_max_size() - query advised max hotplug block size.
+ *
+ * After the first call, the value can never change. Callers looking for the
+ * actual block size should use memory_block_size_bytes. This interface is
+ * intended for use by arch-init when initializing the hotplug block size.
+ *
+ * Return: advised size in bytes, or 0 if never set.
*/
-
-static ssize_t show_mem_start_phys_index(struct device *dev,
- struct device_attribute *attr, char *buf)
+unsigned long memory_block_advised_max_size(void)
{
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
- unsigned long phys_index;
+ memory_block_advised_size_queried = true;
+ return memory_block_advised_size;
+}
- phys_index = mem->start_section_nr / sections_per_block;
- return sprintf(buf, "%08lx\n", phys_index);
+unsigned long __weak memory_block_size_bytes(void)
+{
+ return MIN_MEMORY_BLOCK_SIZE;
}
+EXPORT_SYMBOL_GPL(memory_block_size_bytes);
-static ssize_t show_mem_end_phys_index(struct device *dev,
- struct device_attribute *attr, char *buf)
+/* 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 =
- container_of(dev, struct memory_block, dev);
- unsigned long phys_index;
+ struct memory_block *mem = to_memory_block(dev);
- phys_index = mem->end_section_nr / sections_per_block;
- return sprintf(buf, "%08lx\n", phys_index);
+ return sysfs_emit(buf, "%08lx\n", memory_block_id(mem->start_section_nr));
}
/*
- * Show whether the section of memory is likely to be hot-removable
+ * Legacy interface that we cannot remove. Always indicate "removable"
+ * with CONFIG_MEMORY_HOTREMOVE - bad heuristic.
*/
-static ssize_t show_mem_removable(struct device *dev,
- struct device_attribute *attr, char *buf)
+static ssize_t removable_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
{
- unsigned long i, pfn;
- int ret = 1;
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
-
- for (i = 0; i < sections_per_block; i++) {
- pfn = section_nr_to_pfn(mem->start_section_nr + i);
- ret &= is_mem_section_removable(pfn, PAGES_PER_SECTION);
- }
-
- return sprintf(buf, "%d\n", ret);
+ return sysfs_emit(buf, "%d\n", (int)IS_ENABLED(CONFIG_MEMORY_HOTREMOVE));
}
/*
* online, offline, going offline, etc.
*/
-static ssize_t show_mem_state(struct device *dev,
- struct device_attribute *attr, char *buf)
+static ssize_t state_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
{
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
- ssize_t len = 0;
+ 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:
- len = sprintf(buf, "online\n");
- break;
- case MEM_OFFLINE:
- len = sprintf(buf, "offline\n");
- break;
- case MEM_GOING_OFFLINE:
- len = sprintf(buf, "going-offline\n");
- break;
- default:
- len = sprintf(buf, "ERROR-UNKNOWN-%ld\n",
- mem->state);
- WARN_ON(1);
- break;
+ 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-%d\n", mem->state);
}
- return len;
+ return sysfs_emit(buf, "%s\n", output);
}
-int memory_notify(unsigned long val, void *v)
+int memory_notify(enum memory_block_state state, void *v)
{
- return blocking_notifier_call_chain(&memory_chain, val, v);
+ return blocking_notifier_call_chain(&memory_chain, state, v);
}
-int memory_isolate_notify(unsigned long val, void *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 atomic_notifier_call_chain(&memory_isolate_chain, val, v);
+ return 0;
}
+#endif
/*
- * The probe routines leave the pages reserved, just as the bootmem code does.
- * Make sure they're still that way.
+ * Must acquire mem_hotplug_lock in write mode.
*/
-static bool pages_correctly_reserved(unsigned long start_pfn)
+static int memory_block_online(struct memory_block *mem)
{
- int i, j;
- struct page *page;
- unsigned long pfn = start_pfn;
+ 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);
/*
- * memmap between sections is not contiguous except with
- * SPARSEMEM_VMEMMAP. We lookup the page once per section
- * and assume memmap is contiguous within each section
+ * 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.
*/
- for (i = 0; i < sections_per_block; i++, pfn += PAGES_PER_SECTION) {
- if (WARN_ON_ONCE(!pfn_valid(pfn)))
- return false;
- page = pfn_to_page(pfn);
+ if (mem->altmap)
+ nr_vmemmap_pages = mem->altmap->free;
- for (j = 0; j < PAGES_PER_SECTION; j++) {
- if (PageReserved(page + j))
- continue;
+ mem_hotplug_begin();
+ if (nr_vmemmap_pages) {
+ ret = mhp_init_memmap_on_memory(start_pfn, nr_vmemmap_pages, zone);
+ if (ret)
+ goto out;
+ }
- printk(KERN_WARNING "section number %ld page number %d "
- "not reserved, was it already online?\n",
- pfn_to_section_nr(pfn), j);
+ 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;
+ }
- return false;
- }
+ /*
+ * 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;
}
- return true;
+ if (nr_vmemmap_pages)
+ mhp_deinit_memmap_on_memory(start_pfn, nr_vmemmap_pages);
+
+ mem->zone = NULL;
+out:
+ mem_hotplug_done();
+ return ret;
}
/*
@@ -232,38 +323,28 @@ static bool pages_correctly_reserved(unsigned long start_pfn)
* OK to have direct references to sparsemem variables in here.
*/
static int
-memory_block_action(unsigned long phys_index, unsigned long action, int online_type)
+memory_block_action(struct memory_block *mem, unsigned long action)
{
- unsigned long start_pfn;
- unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
- struct page *first_page;
int ret;
- first_page = pfn_to_page(phys_index << PFN_SECTION_SHIFT);
- start_pfn = page_to_pfn(first_page);
-
switch (action) {
- case MEM_ONLINE:
- if (!pages_correctly_reserved(start_pfn))
- return -EBUSY;
-
- ret = online_pages(start_pfn, nr_pages, online_type);
- break;
- case MEM_OFFLINE:
- ret = offline_pages(start_pfn, nr_pages);
- break;
- default:
- WARN(1, KERN_WARNING "%s(%ld, %ld) unknown action: "
- "%ld\n", __func__, phys_index, action, action);
- ret = -EINVAL;
+ 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 online_type)
+static int memory_block_change_state(struct memory_block *mem,
+ unsigned long to_state, unsigned long from_state_req)
{
int ret = 0;
@@ -273,147 +354,204 @@ static int __memory_block_change_state(struct memory_block *mem,
if (to_state == MEM_OFFLINE)
mem->state = MEM_GOING_OFFLINE;
- ret = memory_block_action(mem->start_section_nr, to_state, online_type);
+ 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 = container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
int ret;
- mutex_lock(&mem->state_mutex);
+ 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 = mem->state == MEM_ONLINE ? 0 :
- __memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE,
- ONLINE_KEEP);
+ ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
+ mem->online_type = MMOP_OFFLINE;
- mutex_unlock(&mem->state_mutex);
return ret;
}
static int memory_subsys_offline(struct device *dev)
{
- struct memory_block *mem = container_of(dev, struct memory_block, 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;
- mutex_lock(&mem->state_mutex);
+ if (online_type < 0)
+ return -EINVAL;
+
+ ret = lock_device_hotplug_sysfs();
+ if (ret)
+ return ret;
- ret = mem->state == MEM_OFFLINE ? 0 :
- __memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE, -1);
+ 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 */
+ }
- mutex_unlock(&mem->state_mutex);
- return ret;
+ unlock_device_hotplug();
+
+ if (ret < 0)
+ return ret;
+ if (ret)
+ return -EINVAL;
+
+ return count;
}
-static int __memory_block_change_state_uevent(struct memory_block *mem,
- unsigned long to_state, unsigned long from_state_req,
- int online_type)
+/*
+ * 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)
{
- int ret = __memory_block_change_state(mem, to_state, from_state_req,
- online_type);
- if (!ret) {
- switch (mem->state) {
- case MEM_OFFLINE:
- kobject_uevent(&mem->dev.kobj, KOBJ_OFFLINE);
- break;
- case MEM_ONLINE:
- kobject_uevent(&mem->dev.kobj, KOBJ_ONLINE);
- break;
- default:
- break;
- }
- }
- return ret;
+ 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));
}
-static int memory_block_change_state(struct memory_block *mem,
- unsigned long to_state, unsigned long from_state_req,
- int online_type)
+#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)
{
- int ret;
+ struct zone *zone;
- mutex_lock(&mem->state_mutex);
- ret = __memory_block_change_state_uevent(mem, to_state, from_state_req,
- online_type);
- mutex_unlock(&mem->state_mutex);
+ zone = zone_for_pfn_range(online_type, nid, group, start_pfn, nr_pages);
+ if (zone == default_zone)
+ return 0;
- return ret;
+ return sysfs_emit_at(buf, len, " %s", zone->name);
}
-static ssize_t
-store_mem_state(struct device *dev,
- struct device_attribute *attr, const char *buf, size_t count)
+
+static ssize_t valid_zones_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
{
- struct memory_block *mem;
- bool offline;
- int ret = -EINVAL;
-
- mem = container_of(dev, struct memory_block, dev);
-
- lock_device_hotplug();
-
- if (!strncmp(buf, "online_kernel", min_t(int, count, 13))) {
- offline = false;
- ret = memory_block_change_state(mem, MEM_ONLINE,
- MEM_OFFLINE, ONLINE_KERNEL);
- } else if (!strncmp(buf, "online_movable", min_t(int, count, 14))) {
- offline = false;
- ret = memory_block_change_state(mem, MEM_ONLINE,
- MEM_OFFLINE, ONLINE_MOVABLE);
- } else if (!strncmp(buf, "online", min_t(int, count, 6))) {
- offline = false;
- ret = memory_block_change_state(mem, MEM_ONLINE,
- MEM_OFFLINE, ONLINE_KEEP);
- } else if(!strncmp(buf, "offline", min_t(int, count, 7))) {
- offline = true;
- ret = memory_block_change_state(mem, MEM_OFFLINE,
- MEM_ONLINE, -1);
+ 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;
+
+ /*
+ * 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.
+ */
+ return sysfs_emit(buf, "%s\n",
+ mem->zone ? mem->zone->name : "none");
}
- if (!ret)
- dev->offline = offline;
- unlock_device_hotplug();
+ default_zone = zone_for_pfn_range(MMOP_ONLINE, nid, group,
+ start_pfn, nr_pages);
- if (ret)
- return ret;
- return count;
+ len = sysfs_emit(buf, "%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);
+ 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);
/*
- * phys_device is a bad name for this. What I really want
- * is a way to differentiate between memory ranges that
- * are part of physical devices that constitute
- * a complete removable unit or fru.
- * i.e. do these ranges belong to the same physical device,
- * s.t. if I offline all of these sections I can then
- * remove the physical device?
+ * Show the memory block size (shared by all memory blocks).
*/
-static ssize_t show_phys_device(struct device *dev,
- struct device_attribute *attr, char *buf)
+static ssize_t block_size_bytes_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
{
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
- return sprintf(buf, "%d\n", mem->phys_device);
+ return sysfs_emit(buf, "%lx\n", memory_block_size_bytes());
}
-static DEVICE_ATTR(phys_index, 0444, show_mem_start_phys_index, NULL);
-static DEVICE_ATTR(end_phys_index, 0444, show_mem_end_phys_index, NULL);
-static DEVICE_ATTR(state, 0644, show_mem_state, store_mem_state);
-static DEVICE_ATTR(phys_device, 0444, show_phys_device, NULL);
-static DEVICE_ATTR(removable, 0444, show_mem_removable, NULL);
+static DEVICE_ATTR_RO(block_size_bytes);
/*
- * Block size attribute stuff
+ * Memory auto online policy.
*/
-static ssize_t
-print_block_size(struct device *dev, struct device_attribute *attr,
- char *buf)
+
+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_get_default_online_type()]);
+}
+
+static ssize_t auto_online_blocks_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
{
- return sprintf(buf, "%lx\n", get_memory_block_size());
+ const int online_type = mhp_online_type_from_str(buf);
+
+ if (online_type < 0)
+ return -EINVAL;
+
+ mhp_set_default_online_type(online_type);
+ return count;
}
-static DEVICE_ATTR(block_size_bytes, 0444, print_block_size, NULL);
+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_check_hotplug_support());
+}
+static DEVICE_ATTR_RO(crash_hotplug);
+#endif
/*
* Some architectures will have custom drivers to do this, and
@@ -422,36 +560,39 @@ static DEVICE_ATTR(block_size_bytes, 0444, print_block_size, NULL);
* and will require this interface.
*/
#ifdef CONFIG_ARCH_MEMORY_PROBE
-static ssize_t
-memory_probe_store(struct device *dev, struct device_attribute *attr,
- const char *buf, size_t count)
+static ssize_t probe_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
{
u64 phys_addr;
- int nid;
- int i, ret;
+ int nid, ret;
unsigned long pages_per_block = PAGES_PER_SECTION * sections_per_block;
- phys_addr = simple_strtoull(buf, NULL, 0);
+ ret = kstrtoull(buf, 0, &phys_addr);
+ if (ret)
+ return ret;
if (phys_addr & ((pages_per_block << PAGE_SHIFT) - 1))
return -EINVAL;
- for (i = 0; i < sections_per_block; i++) {
- nid = memory_add_physaddr_to_nid(phys_addr);
- ret = add_memory(nid, phys_addr,
- PAGES_PER_SECTION << PAGE_SHIFT);
- if (ret)
- goto out;
+ ret = lock_device_hotplug_sysfs();
+ if (ret)
+ return ret;
- phys_addr += MIN_MEMORY_BLOCK_SIZE;
- }
+ 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(probe, S_IWUSR, NULL, memory_probe_store);
+static DEVICE_ATTR_WO(probe);
#endif
#ifdef CONFIG_MEMORY_FAILURE
@@ -460,97 +601,86 @@ static DEVICE_ATTR(probe, S_IWUSR, NULL, memory_probe_store);
*/
/* Soft offline a page */
-static ssize_t
-store_soft_offline_page(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t count)
+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 (strict_strtoull(buf, 0, &pfn) < 0)
+ if (kstrtoull(buf, 0, &pfn) < 0)
return -EINVAL;
pfn >>= PAGE_SHIFT;
- if (!pfn_valid(pfn))
- return -ENXIO;
- ret = soft_offline_page(pfn_to_page(pfn), 0);
+ ret = soft_offline_page(pfn, 0);
return ret == 0 ? count : ret;
}
/* Forcibly offline a page, including killing processes. */
-static ssize_t
-store_hard_offline_page(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t count)
+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 (strict_strtoull(buf, 0, &pfn) < 0)
+ if (kstrtoull(buf, 0, &pfn) < 0)
return -EINVAL;
pfn >>= PAGE_SHIFT;
- ret = memory_failure(pfn, 0, 0);
+ ret = memory_failure(pfn, MF_SW_SIMULATED);
+ if (ret == -EOPNOTSUPP)
+ ret = 0;
return ret ? ret : count;
}
-static DEVICE_ATTR(soft_offline_page, S_IWUSR, NULL, store_soft_offline_page);
-static DEVICE_ATTR(hard_offline_page, S_IWUSR, NULL, store_hard_offline_page);
+static DEVICE_ATTR_WO(soft_offline_page);
+static DEVICE_ATTR_WO(hard_offline_page);
#endif
-/*
- * Note that phys_device is optional. It is here to allow for
- * differentiation between which *physical* devices each
- * section belongs to...
- */
+/* See phys_device_show(). */
int __weak arch_get_memory_phys_device(unsigned long start_pfn)
{
return 0;
}
/*
- * A reference for the returned object is held and the reference for the
- * hinted object is released.
+ * A reference for the returned memory block device is acquired.
+ *
+ * Called under device_hotplug_lock.
*/
-struct memory_block *find_memory_block_hinted(struct mem_section *section,
- struct memory_block *hint)
+struct memory_block *find_memory_block_by_id(unsigned long block_id)
{
- int block_id = base_memory_block_id(__section_nr(section));
- struct device *hintdev = hint ? &hint->dev : NULL;
- struct device *dev;
+ struct memory_block *mem;
- dev = subsys_find_device_by_id(&memory_subsys, block_id, hintdev);
- if (hint)
- put_device(&hint->dev);
- if (!dev)
- return NULL;
- return container_of(dev, struct memory_block, dev);
+ mem = xa_load(&memory_blocks, block_id);
+ if (mem)
+ get_device(&mem->dev);
+ return mem;
}
/*
- * For now, we have a linear search to go find the appropriate
- * memory_block corresponding to a particular phys_index. If
- * this gets to be a real problem, we can always use a radix
- * tree or something here.
- *
- * This could be made generic for all device subsystems.
+ * Called under device_hotplug_lock.
*/
-struct memory_block *find_memory_block(struct mem_section *section)
+struct memory_block *find_memory_block(unsigned long section_nr)
{
- return find_memory_block_hinted(section, NULL);
+ 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_end_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 struct attribute_group memory_memblk_attr_group = {
+static const struct attribute_group memory_memblk_attr_group = {
.attrs = memory_memblk_attrs,
};
@@ -559,13 +689,9 @@ static const struct attribute_group *memory_memblk_attr_groups[] = {
NULL,
};
-/*
- * register_memory - Setup a sysfs device for a memory block
- */
-static
-int register_memory(struct memory_block *memory)
+static int __add_memory_block(struct memory_block *memory)
{
- int error;
+ int ret;
memory->dev.bus = &memory_subsys;
memory->dev.id = memory->start_section_nr / sections_per_block;
@@ -573,132 +699,222 @@ int register_memory(struct memory_block *memory)
memory->dev.groups = memory_memblk_attr_groups;
memory->dev.offline = memory->state == MEM_OFFLINE;
- error = device_register(&memory->dev);
- return error;
+ 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 int init_memory_block(struct memory_block **memory,
- struct mem_section *section, unsigned long state)
+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_early() - Indicate that early system RAM falling into
+ * this memory block device (partially) belongs
+ * to the given node.
+ * @mem: The memory block device.
+ * @nid: The node id.
+ *
+ * Indicate that early system RAM falling into this memory block (partially)
+ * belongs to the given node. This will also properly set/adjust mem->zone based
+ * on the zone ranges of the given node.
+ *
+ * Memory hotplug handles this on memory block creation, where we can only have
+ * a single nid span a memory block.
+ */
+void memory_block_add_nid_early(struct memory_block *mem, int nid)
+{
+ if (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, int nid, unsigned long state,
+ struct vmem_altmap *altmap,
+ struct memory_group *group)
{
struct memory_block *mem;
- unsigned long start_pfn;
- int scn_nr;
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;
- scn_nr = __section_nr(section);
- mem->start_section_nr =
- base_memory_block_id(scn_nr) * sections_per_block;
- mem->end_section_nr = mem->start_section_nr + sections_per_block - 1;
+ mem->start_section_nr = block_id * sections_per_block;
mem->state = state;
- mem->section_count++;
- mutex_init(&mem->state_mutex);
- start_pfn = section_nr_to_pfn(mem->start_section_nr);
- mem->phys_device = arch_get_memory_phys_device(start_pfn);
+ mem->nid = nid;
+ 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;
- ret = register_memory(mem);
+ if (group) {
+ mem->group = group;
+ list_add(&mem->group_next, &group->memory_blocks);
+ }
- *memory = mem;
- return ret;
+ return 0;
}
-static int add_memory_section(int nid, struct mem_section *section,
- struct memory_block **mem_p,
- unsigned long state, enum mem_add_context context)
+static void remove_memory_block(struct memory_block *memory)
{
- struct memory_block *mem = NULL;
- int scn_nr = __section_nr(section);
- int ret = 0;
-
- mutex_lock(&mem_sysfs_mutex);
+ if (WARN_ON_ONCE(memory->dev.bus != &memory_subsys))
+ return;
- if (context == BOOT) {
- /* same memory block ? */
- if (mem_p && *mem_p)
- if (scn_nr >= (*mem_p)->start_section_nr &&
- scn_nr <= (*mem_p)->end_section_nr) {
- mem = *mem_p;
- kobject_get(&mem->dev.kobj);
- }
- } else
- mem = find_memory_block(section);
-
- if (mem) {
- mem->section_count++;
- kobject_put(&mem->dev.kobj);
- } else {
- ret = init_memory_block(&mem, section, state);
- /* store memory_block pointer for next loop */
- if (!ret && context == BOOT)
- if (mem_p)
- *mem_p = mem;
- }
+ WARN_ON(xa_erase(&memory_blocks, memory->dev.id) == NULL);
- if (!ret) {
- if (context == HOTPLUG &&
- mem->section_count == sections_per_block)
- ret = register_mem_sect_under_node(mem, nid);
+ if (memory->group) {
+ list_del(&memory->group_next);
+ memory->group = NULL;
}
- mutex_unlock(&mem_sysfs_mutex);
- return ret;
+ /* drop the ref. we got via find_memory_block() */
+ put_device(&memory->dev);
+ device_unregister(&memory->dev);
}
/*
- * need an interface for the VM to add new memory regions,
- * but without onlining it.
+ * 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 register_new_memory(int nid, struct mem_section *section)
-{
- return add_memory_section(nid, section, NULL, MEM_OFFLINE, HOTPLUG);
-}
-
-#ifdef CONFIG_MEMORY_HOTREMOVE
-static void
-unregister_memory(struct memory_block *memory)
-{
- BUG_ON(memory->dev.bus != &memory_subsys);
-
- /* drop the ref. we got in remove_memory_block() */
- kobject_put(&memory->dev.kobj);
- device_unregister(&memory->dev);
-}
-
-static int remove_memory_block(unsigned long node_id,
- struct mem_section *section, int phys_device)
+int create_memory_block_devices(unsigned long start, unsigned long size,
+ int nid, 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;
- mutex_lock(&mem_sysfs_mutex);
- mem = find_memory_block(section);
- unregister_mem_sect_under_nodes(mem, __section_nr(section));
-
- mem->section_count--;
- if (mem->section_count == 0)
- unregister_memory(mem);
- else
- kobject_put(&mem->dev.kobj);
+ if (WARN_ON_ONCE(!IS_ALIGNED(start, memory_block_size_bytes()) ||
+ !IS_ALIGNED(size, memory_block_size_bytes())))
+ return -EINVAL;
- mutex_unlock(&mem_sysfs_mutex);
- return 0;
+ for (block_id = start_block_id; block_id != end_block_id; block_id++) {
+ ret = add_memory_block(block_id, nid, MEM_OFFLINE, 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;
}
-int unregister_memory_section(struct mem_section *section)
+/*
+ * 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)
{
- if (!present_section(section))
- return -EINVAL;
+ 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;
- return remove_memory_block(0, section, 0);
-}
-#endif /* CONFIG_MEMORY_HOTREMOVE */
+ if (WARN_ON_ONCE(!IS_ALIGNED(start, memory_block_size_bytes()) ||
+ !IS_ALIGNED(size, memory_block_size_bytes())))
+ return;
-/* return true if the memory block is offlined, otherwise, return false */
-bool is_memblock_offlined(struct memory_block *mem)
-{
- return mem->state == MEM_OFFLINE;
+ 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[] = {
@@ -712,10 +928,14 @@ static struct attribute *memory_root_attrs[] = {
#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 struct attribute_group memory_root_attr_group = {
+static const struct attribute_group memory_root_attr_group = {
.attrs = memory_root_attrs,
};
@@ -725,41 +945,306 @@ static const struct attribute_group *memory_root_attr_groups[] = {
};
/*
- * Initialize the sysfs support for memory devices...
+ * 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.
*/
-int __init memory_dev_init(void)
+void __init memory_dev_init(void)
{
- unsigned int i;
int ret;
- int err;
- unsigned long block_sz;
- struct memory_block *mem = NULL;
+ unsigned long block_sz, block_id, 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)
- goto out;
-
- block_sz = get_memory_block_size();
- sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
+ panic("%s() failed to register subsystem: %d\n", __func__, ret);
/*
- * Create entries for memory sections that were found
- * during boot and have been initialized
+ * Create entries for memory sections that were found during boot
+ * and have been initialized. Use @block_id to track the last
+ * handled block and initialize it to an invalid value (ULONG_MAX)
+ * to bypass the block ID matching check for the first present
+ * block so that it can be covered.
*/
- for (i = 0; i < NR_MEM_SECTIONS; i++) {
- if (!present_section_nr(i))
+ block_id = ULONG_MAX;
+ for_each_present_section_nr(0, nr) {
+ if (block_id != ULONG_MAX && memory_block_id(nr) == block_id)
continue;
- /* don't need to reuse memory_block if only one per block */
- err = add_memory_section(0, __nr_to_section(i),
- (sections_per_block == 1) ? NULL : &mem,
- MEM_ONLINE,
- BOOT);
- if (!ret)
- ret = err;
+
+ block_id = memory_block_id(nr);
+ ret = add_memory_block(block_id, NUMA_NO_NODE, MEM_ONLINE, NULL, NULL);
+ if (ret) {
+ panic("%s() failed to add memory block: %d\n",
+ __func__, ret);
+ }
}
+}
-out:
- if (ret)
- printk(KERN_ERR "%s() failed: %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