/*
* online, offline, going offline, etc.
*/
static ssize_t show_mem_state(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct memory_block *mem = to_memory_block(dev);
ssize_t len = 0;
/*
* 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;
}
return len;
}
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 nr_pages = PAGES_PER_SECTION * sections_per_block;
struct page *first_page;
struct zone *zone;
start_pfn = section_nr_to_pfn(mem->start_section_nr);
end_pfn = start_pfn + nr_pages;
first_page = pfn_to_page(start_pfn);
/* The block contains more than one zone can not be offlined. */
if (!test_pages_in_a_zone(start_pfn, end_pfn))
return sprintf(buf, "none\n");
zone = page_zone(first_page);
if (zone_idx(zone) == ZONE_MOVABLE - 1) {
/*The mem block is the last memoryblock of this zone.*/
if (end_pfn == 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 (start_pfn == zone->zone_start_pfn)
return sprintf(buf, "%s %s\n",
zone->name, (zone - 1)->name);
}
return sprintf(buf, "%s\n", zone->name);
}
static ssize_t show_mem_start_phys_index(struct device *dev,
struct device_attribute *attr, char *buf)
{
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 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
store_mem_state(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
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;
return count;
}
static ssize_t
store_mem_state(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
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;
}
switch (online_type) {
case MMOP_ONLINE_KERNEL:
case MMOP_ONLINE_MOVABLE:
case MMOP_ONLINE_KEEP:
/*
* mem->online_type is not protected so there can be a
* race here. However, when racing online, the first
* will succeed and the second will just return as the
* block will already be online. The online type
* could be either one, but that is expected.
*/
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 */
}
err:
unlock_device_hotplug();
if (ret)
return ret;
return count;
}
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);
}
/*
* A reference for the returned object is held and the reference for the
* hinted object is released.
*/
struct memory_block *find_memory_block_hinted(struct mem_section *section,
struct memory_block *hint)
{
int block_id = base_memory_block_id(__section_nr(section));
struct device *hintdev = hint ? &hint->dev : NULL;
struct device *dev;
dev = subsys_find_device_by_id(&memory_subsys, block_id, hintdev);
if (hint)
put_device(&hint->dev);
if (!dev)
return NULL;
return to_memory_block(dev);
}
/*
* Show whether the section of memory is likely to be hot-removable
*/
static ssize_t show_mem_removable(struct device *dev,
struct device_attribute *attr, char *buf)
{
unsigned long i, pfn;
int ret = 1;
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))
continue;
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);
}
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 nr_pages = PAGES_PER_SECTION * sections_per_block;
struct page *first_page;
struct zone *zone;
int zone_shift = 0;
start_pfn = section_nr_to_pfn(mem->start_section_nr);
end_pfn = start_pfn + nr_pages;
first_page = pfn_to_page(start_pfn);
/* The block contains more than one zone can not be offlined. */
if (!test_pages_in_a_zone(start_pfn, end_pfn))
return sprintf(buf, "none\n");
zone = page_zone(first_page);
/* MMOP_ONLINE_KEEP */
sprintf(buf, "%s", zone->name);
/* MMOP_ONLINE_KERNEL */
zone_shift = zone_can_shift(start_pfn, nr_pages, ZONE_NORMAL);
if (zone_shift) {
strcat(buf, " ");
strcat(buf, (zone + zone_shift)->name);
}
/* MMOP_ONLINE_MOVABLE */
zone_shift = zone_can_shift(start_pfn, nr_pages, ZONE_MOVABLE);
if (zone_shift) {
strcat(buf, " ");
strcat(buf, (zone + zone_shift)->name);
}
strcat(buf, "\n");
return strlen(buf);
}
/* 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;
/*
* 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;
ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
/* clear online_type */
mem->online_type = -1;
return ret;
}
static void memory_block_release(struct device *dev)
{
struct memory_block *mem = to_memory_block(dev);
kfree(mem);
}
/*
* 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?
*/
static ssize_t show_phys_device(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct memory_block *mem = to_memory_block(dev);
return sprintf(buf, "%d\n", mem->phys_device);
}
