From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Introduce .offline() and .online() callbacks for memory_subsys
that will allow the generic device_offline() and device_online()
to be used with device objects representing memory blocks. That,
in turn, allows the ACPI subsystem to use device_offline() to put
removable memory blocks offline, if possible, before removing
memory modules holding them.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/base/memory.c | 84 ++++++++++++++++++++++++++++++-----------
include/linux/memory_hotplug.h | 2
2 files changed, 64 insertions(+), 22 deletions(-)
Index: linux-pm/drivers/base/memory.c
===================================================================
--- linux-pm.orig/drivers/base/memory.c
+++ linux-pm/drivers/base/memory.c
@@ -37,9 +37,14 @@ static inline int base_memory_block_id(i
return section_nr / sections_per_block;
}
+static int memory_subsys_online(struct device *dev, unsigned int type);
+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);
@@ -294,16 +299,7 @@ static int __memory_block_change_state(s
}
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;
}
@@ -321,27 +317,66 @@ static int memory_block_change_state(str
return ret;
}
+
+static int memory_subsys_online(struct device *dev, unsigned int type)
+{
+ struct memory_block *mem = container_of(dev, struct memory_block, dev);
+
+ if (type < ONLINE_KEEP || type > ONLINE_KERNEL)
+ return -EINVAL;
+
+ return memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE, type);
+}
+
+static int memory_block_online(struct device *dev, unsigned int type)
+{
+ int ret = memory_subsys_online(dev, type);
+
+ if (!ret) {
+ dev->online_type = type;
+ kobject_uevent(&dev->kobj, KOBJ_ONLINE);
+ }
+
+ return ret;
+}
+
+static int memory_subsys_offline(struct device *dev)
+{
+ struct memory_block *mem = container_of(dev, struct memory_block, dev);
+
+ return memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE, -1);
+}
+
+static int memory_block_offline(struct device *dev)
+{
+ int ret = memory_subsys_offline(dev);
+
+ if (!ret) {
+ dev->online_type = 0;
+ kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
+ }
+
+ return ret;
+}
+
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);
+ lock_device_hotplug();
if (!strncmp(buf, "online_kernel", min_t(int, count, 13)))
- ret = memory_block_change_state(mem, MEM_ONLINE,
- MEM_OFFLINE, ONLINE_KERNEL);
+ ret = memory_block_online(dev, 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);
+ ret = memory_block_online(dev, ONLINE_MOVABLE);
else if (!strncmp(buf, "online", min_t(int, count, 6)))
- ret = memory_block_change_state(mem, MEM_ONLINE,
- MEM_OFFLINE, ONLINE_KEEP);
+ ret = memory_block_online(dev, ONLINE_KEEP);
else if(!strncmp(buf, "offline", min_t(int, count, 7)))
- ret = memory_block_change_state(mem, MEM_OFFLINE,
- MEM_ONLINE, -1);
+ ret = memory_block_offline(dev);
+
+ unlock_device_hotplug();
if (ret)
return ret;
@@ -686,10 +721,17 @@ int offline_memory_block(struct memory_b
{
int ret = 0;
+ lock_device_hotplug();
mutex_lock(&mem->state_mutex);
- if (mem->state != MEM_OFFLINE)
+ if (mem->state != MEM_OFFLINE) {
ret = __memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE, -1);
+ if (!ret) {
+ mem->dev.online_type = 0;
+ kobject_uevent(&mem->dev.kobj, KOBJ_OFFLINE);
+ }
+ }
mutex_unlock(&mem->state_mutex);
+ unlock_device_hotplug();
return ret;
}
Index: linux-pm/include/linux/memory_hotplug.h
===================================================================
--- linux-pm.orig/include/linux/memory_hotplug.h
+++ linux-pm/include/linux/memory_hotplug.h
@@ -28,7 +28,7 @@ enum {
/* Types for control the zone type of onlined memory */
enum {
- ONLINE_KEEP,
+ ONLINE_KEEP = 1,
ONLINE_KERNEL,
ONLINE_MOVABLE,
};
--
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