1 files changed, 27 insertions, 4 deletions

diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 44e7de6ce694..86c88216a503 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -275,13 +275,11 @@ memory_block_action(unsigned long phys_index, unsigned long action)
         return ret;
 }
 
-static int memory_block_change_state(struct memory_block *mem,
+static int __memory_block_change_state(struct memory_block *mem,
                 unsigned long to_state, unsigned long from_state_req)
 {
         int ret = 0;
 
-        mutex_lock(&mem->state_mutex);
-
         if (mem->state != from_state_req) {
                 ret = -EINVAL;
                 goto out;
@@ -309,10 +307,20 @@ static int memory_block_change_state(struct memory_block *mem,
                 break;
         }
 out:
-        mutex_unlock(&mem->state_mutex);
         return ret;
 }
 
+static int memory_block_change_state(struct memory_block *mem,
+                unsigned long to_state, unsigned long from_state_req)
+{
+        int ret;
+
+        mutex_lock(&mem->state_mutex);
+        ret = __memory_block_change_state(mem, to_state, from_state_req);
+        mutex_unlock(&mem->state_mutex);
+
+        return ret;
+}
 static ssize_t
 store_mem_state(struct device *dev,
                 struct device_attribute *attr, const char *buf, size_t count)
@@ -653,6 +661,21 @@ int unregister_memory_section(struct mem_section *section)
 }
 
 /*
+ * 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);
+        mutex_unlock(&mem->state_mutex);
+
+        return ret;
+}
+
+/*
  * Initialize the sysfs support for memory devices...
  */
 int __init memory_dev_init(void)