#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>
#define MEMORY_CLASS_NAME "memory"
+#define to_memory_block(dev) container_of(dev, struct memory_block, dev)
+
static int sections_per_block;
static inline int base_memory_block_id(int section_nr)
return section_nr / 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 = {
.name = MEMORY_CLASS_NAME,
.dev_name = MEMORY_CLASS_NAME,
+ .online = memory_subsys_online,
+ .offline = memory_subsys_offline,
};
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 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);
kfree(mem);
}
-/*
- * register_memory - Setup a sysfs device for a memory block
- */
-static
-int register_memory(struct memory_block *memory)
-{
- int error;
-
- memory->dev.bus = &memory_subsys;
- memory->dev.id = memory->start_section_nr / sections_per_block;
- memory->dev.release = memory_block_release;
-
- error = device_register(&memory->dev);
- return error;
-}
-
unsigned long __weak memory_block_size_bytes(void)
{
return MIN_MEMORY_BLOCK_SIZE;
static ssize_t show_mem_start_phys_index(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
unsigned long phys_index;
phys_index = mem->start_section_nr / sections_per_block;
return sprintf(buf, "%08lx\n", phys_index);
}
-static ssize_t show_mem_end_phys_index(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
- unsigned long phys_index;
-
- phys_index = mem->end_section_nr / sections_per_block;
- return sprintf(buf, "%08lx\n", phys_index);
-}
-
/*
* Show whether the section of memory is likely to be hot-removable
*/
{
unsigned long i, pfn;
int ret = 1;
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
for (i = 0; i < sections_per_block; i++) {
if (!present_section_nr(mem->start_section_nr + i))
static ssize_t show_mem_state(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
ssize_t len = 0;
/*
* 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:
+ 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;
}
return len;
/*
* MEMORY_HOTPLUG depends on SPARSEMEM in mm/Kconfig, so it is
* OK to have direct references to sparsemem variables in here.
+ * Must already be protected by mem_hotplug_begin().
*/
static int
memory_block_action(unsigned long phys_index, unsigned long action, int online_type)
struct page *first_page;
int ret;
- first_page = pfn_to_page(phys_index << PFN_SECTION_SHIFT);
- start_pfn = page_to_pfn(first_page);
+ start_pfn = section_nr_to_pfn(phys_index);
+ first_page = pfn_to_page(start_pfn);
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:
+ 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;
}
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;
- if (mem->state != from_state_req) {
- ret = -EINVAL;
- goto out;
- }
+ if (mem->state != from_state_req)
+ return -EINVAL;
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->start_section_nr, to_state,
+ mem->online_type);
- if (ret) {
- mem->state = from_state_req;
- goto out;
- }
+ mem->state = ret ? from_state_req : to_state;
- mem->state = to_state;
- 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;
- }
-out:
return ret;
}
-static int memory_block_change_state(struct memory_block *mem,
- unsigned long to_state, unsigned long from_state_req,
- int online_type)
+/* 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;
- mutex_lock(&mem->state_mutex);
- ret = __memory_block_change_state(mem, to_state, from_state_req,
- online_type);
- mutex_unlock(&mem->state_mutex);
+ if (mem->state == MEM_ONLINE)
+ return 0;
+
+ /*
+ * If we are called from store_mem_state(), online_type will be
+ * set >= 0 Otherwise we were called from the device online
+ * attribute and need to set the online_type.
+ */
+ if (mem->online_type < 0)
+ mem->online_type = MMOP_ONLINE_KEEP;
+
+ /* Already under protection of mem_hotplug_begin() */
+ ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
+
+ /* clear online_type */
+ mem->online_type = -1;
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;
+
+ /* Can't offline block with non-present sections */
+ if (mem->section_count != sections_per_block)
+ return -EINVAL;
+
+ return memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE);
+}
+
static ssize_t
store_mem_state(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
- struct memory_block *mem;
- int ret = -EINVAL;
-
- mem = container_of(dev, struct memory_block, dev);
-
- if (!strncmp(buf, "online_kernel", min_t(int, count, 13)))
- ret = memory_block_change_state(mem, MEM_ONLINE,
- MEM_OFFLINE, ONLINE_KERNEL);
- else if (!strncmp(buf, "online_movable", min_t(int, count, 14)))
- ret = memory_block_change_state(mem, MEM_ONLINE,
- MEM_OFFLINE, ONLINE_MOVABLE);
- else if (!strncmp(buf, "online", min_t(int, count, 6)))
- ret = memory_block_change_state(mem, MEM_ONLINE,
- MEM_OFFLINE, ONLINE_KEEP);
- else if(!strncmp(buf, "offline", min_t(int, count, 7)))
- ret = memory_block_change_state(mem, MEM_OFFLINE,
- MEM_ONLINE, -1);
+ struct memory_block *mem = to_memory_block(dev);
+ int ret, online_type;
+
+ ret = lock_device_hotplug_sysfs();
+ if (ret)
+ return ret;
+
+ if (sysfs_streq(buf, "online_kernel"))
+ online_type = MMOP_ONLINE_KERNEL;
+ else if (sysfs_streq(buf, "online_movable"))
+ online_type = MMOP_ONLINE_MOVABLE;
+ else if (sysfs_streq(buf, "online"))
+ online_type = MMOP_ONLINE_KEEP;
+ else if (sysfs_streq(buf, "offline"))
+ online_type = MMOP_OFFLINE;
+ else {
+ ret = -EINVAL;
+ goto err;
+ }
+
+ /*
+ * Memory hotplug needs to hold mem_hotplug_begin() for probe to find
+ * the correct memory block to online before doing device_online(dev),
+ * which will take dev->mutex. Take the lock early to prevent an
+ * inversion, memory_subsys_online() callbacks will be implemented by
+ * assuming it's already protected.
+ */
+ mem_hotplug_begin();
+
+ switch (online_type) {
+ case MMOP_ONLINE_KERNEL:
+ case MMOP_ONLINE_MOVABLE:
+ case MMOP_ONLINE_KEEP:
+ 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 */
+ }
+
+ mem_hotplug_done();
+err:
+ unlock_device_hotplug();
if (ret)
return ret;
static ssize_t show_phys_device(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct memory_block *mem =
- container_of(dev, struct memory_block, dev);
+ struct memory_block *mem = to_memory_block(dev);
return sprintf(buf, "%d\n", mem->phys_device);
}
+#ifdef CONFIG_MEMORY_HOTREMOVE
+static ssize_t show_valid_zones(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct memory_block *mem = to_memory_block(dev);
+ unsigned long start_pfn, end_pfn;
+ unsigned long valid_start, valid_end;
+ unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
+ struct zone *zone;
+
+ start_pfn = section_nr_to_pfn(mem->start_section_nr);
+ end_pfn = start_pfn + nr_pages;
+
+ /* The block contains more than one zone can not be offlined. */
+ if (!test_pages_in_a_zone(start_pfn, end_pfn, &valid_start, &valid_end))
+ return sprintf(buf, "none\n");
+
+ zone = page_zone(pfn_to_page(valid_start));
+
+ if (zone_idx(zone) == ZONE_MOVABLE - 1) {
+ /*The mem block is the last memoryblock of this zone.*/
+ if (valid_end == zone_end_pfn(zone))
+ return sprintf(buf, "%s %s\n",
+ zone->name, (zone + 1)->name);
+ }
+
+ if (zone_idx(zone) == ZONE_MOVABLE) {
+ /*The mem block is the first memoryblock of ZONE_MOVABLE.*/
+ if (valid_start == zone->zone_start_pfn)
+ return sprintf(buf, "%s %s\n",
+ zone->name, (zone - 1)->name);
+ }
+
+ return sprintf(buf, "%s\n", zone->name);
+}
+static DEVICE_ATTR(valid_zones, 0444, show_valid_zones, NULL);
+#endif
+
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);
-#define mem_create_simple_file(mem, attr_name) \
- device_create_file(&mem->dev, &dev_attr_##attr_name)
-#define mem_remove_simple_file(mem, attr_name) \
- device_remove_file(&mem->dev, &dev_attr_##attr_name)
-
/*
* Block size attribute stuff
*/
static DEVICE_ATTR(block_size_bytes, 0444, print_block_size, NULL);
-static int block_size_init(void)
-{
- return device_create_file(memory_subsys.dev_root,
- &dev_attr_block_size_bytes);
-}
-
/*
* Some architectures will have custom drivers to do this, and
* will not need to do it from userspace. The fake hot-add code
int i, 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;
out:
return ret;
}
-static DEVICE_ATTR(probe, S_IWUSR, NULL, memory_probe_store);
-static int memory_probe_init(void)
-{
- return device_create_file(memory_subsys.dev_root, &dev_attr_probe);
-}
-#else
-static inline int memory_probe_init(void)
-{
- return 0;
-}
+static DEVICE_ATTR(probe, S_IWUSR, NULL, memory_probe_store);
#endif
#ifdef CONFIG_MEMORY_FAILURE
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))
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);
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 __init int memory_fail_init(void)
-{
- int err;
-
- err = device_create_file(memory_subsys.dev_root,
- &dev_attr_soft_offline_page);
- if (!err)
- err = device_create_file(memory_subsys.dev_root,
- &dev_attr_hard_offline_page);
- return err;
-}
-#else
-static inline int memory_fail_init(void)
-{
- return 0;
-}
#endif
/*
put_device(&hint->dev);
if (!dev)
return NULL;
- return container_of(dev, struct memory_block, dev);
+ return to_memory_block(dev);
}
/*
return find_memory_block_hinted(section, NULL);
}
+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 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,
+};
+
+/*
+ * register_memory - Setup a sysfs device for a memory block
+ */
+static
+int register_memory(struct memory_block *memory)
+{
+ 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;
+
+ return device_register(&memory->dev);
+}
+
static int init_memory_block(struct memory_block **memory,
struct mem_section *section, unsigned long state)
{
mem->end_section_nr = mem->start_section_nr + sections_per_block - 1;
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);
ret = register_memory(mem);
- if (!ret)
- ret = mem_create_simple_file(mem, phys_index);
- if (!ret)
- ret = mem_create_simple_file(mem, end_phys_index);
- if (!ret)
- ret = mem_create_simple_file(mem, state);
- if (!ret)
- ret = mem_create_simple_file(mem, phys_device);
- if (!ret)
- ret = mem_create_simple_file(mem, removable);
*memory = mem;
return ret;
}
-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 int add_memory_block(int base_section_nr)
{
- struct memory_block *mem = NULL;
- int scn_nr = __section_nr(section);
- int ret = 0;
-
- mutex_lock(&mem_sysfs_mutex);
-
- 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;
- }
+ struct memory_block *mem;
+ int i, ret, section_count = 0, section_nr;
- if (!ret) {
- if (context == HOTPLUG &&
- mem->section_count == sections_per_block)
- ret = register_mem_sect_under_node(mem, nid);
+ for (i = base_section_nr;
+ (i < base_section_nr + sections_per_block) && i < NR_MEM_SECTIONS;
+ i++) {
+ if (!present_section_nr(i))
+ continue;
+ if (section_count == 0)
+ section_nr = i;
+ section_count++;
}
- mutex_unlock(&mem_sysfs_mutex);
- return ret;
+ if (section_count == 0)
+ return 0;
+ ret = init_memory_block(&mem, __nr_to_section(section_nr), MEM_ONLINE);
+ if (ret)
+ return ret;
+ mem->section_count = section_count;
+ return 0;
}
+
/*
* need an interface for the VM to add new memory regions,
* but without onlining it.
*/
int register_new_memory(int nid, struct mem_section *section)
{
- return add_memory_section(nid, section, NULL, MEM_OFFLINE, HOTPLUG);
+ int ret = 0;
+ struct memory_block *mem;
+
+ mutex_lock(&mem_sysfs_mutex);
+
+ mem = find_memory_block(section);
+ if (mem) {
+ mem->section_count++;
+ put_device(&mem->dev);
+ } else {
+ ret = init_memory_block(&mem, section, MEM_OFFLINE);
+ if (ret)
+ goto out;
+ }
+
+ if (mem->section_count == sections_per_block)
+ ret = register_mem_sect_under_node(mem, nid);
+out:
+ mutex_unlock(&mem_sysfs_mutex);
+ return ret;
}
#ifdef CONFIG_MEMORY_HOTREMOVE
BUG_ON(memory->dev.bus != &memory_subsys);
/* drop the ref. we got in remove_memory_block() */
- kobject_put(&memory->dev.kobj);
+ put_device(&memory->dev);
device_unregister(&memory->dev);
}
unregister_mem_sect_under_nodes(mem, __section_nr(section));
mem->section_count--;
- if (mem->section_count == 0) {
- mem_remove_simple_file(mem, phys_index);
- mem_remove_simple_file(mem, end_phys_index);
- mem_remove_simple_file(mem, state);
- mem_remove_simple_file(mem, phys_device);
- mem_remove_simple_file(mem, removable);
+ if (mem->section_count == 0)
unregister_memory(mem);
- } else
- kobject_put(&mem->dev.kobj);
+ else
+ put_device(&mem->dev);
mutex_unlock(&mem_sysfs_mutex);
return 0;
}
#endif /* CONFIG_MEMORY_HOTREMOVE */
-/*
- * offline one memory block. If the memory block has been offlined, do nothing.
- */
-int offline_memory_block(struct memory_block *mem)
-{
- int ret = 0;
-
- mutex_lock(&mem->state_mutex);
- if (mem->state != MEM_OFFLINE)
- ret = __memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE, -1);
- mutex_unlock(&mem->state_mutex);
-
- return ret;
-}
-
/* return true if the memory block is offlined, otherwise, return false */
bool is_memblock_offlined(struct memory_block *mem)
{
return mem->state == MEM_OFFLINE;
}
+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,
+ NULL
+};
+
+static 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...
*/
int ret;
int err;
unsigned long block_sz;
- struct memory_block *mem = NULL;
- ret = subsys_system_register(&memory_subsys, NULL);
+ ret = subsys_system_register(&memory_subsys, memory_root_attr_groups);
if (ret)
goto out;
* Create entries for memory sections that were found
* during boot and have been initialized
*/
- for (i = 0; i < NR_MEM_SECTIONS; i++) {
- if (!present_section_nr(i))
- 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);
+ mutex_lock(&mem_sysfs_mutex);
+ for (i = 0; i < NR_MEM_SECTIONS; i += sections_per_block) {
+ err = add_memory_block(i);
if (!ret)
ret = err;
}
+ mutex_unlock(&mem_sysfs_mutex);
- err = memory_probe_init();
- if (!ret)
- ret = err;
- err = memory_fail_init();
- if (!ret)
- ret = err;
- err = block_size_init();
- if (!ret)
- ret = err;
out:
if (ret)
printk(KERN_ERR "%s() failed: %d\n", __func__, ret);