3 files changed, 61 insertions, 5 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)
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index e64fe80eba96..95573ec4ee6c 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -10,6 +10,7 @@ struct page;
 struct zone;
 struct pglist_data;
 struct mem_section;
+struct memory_block;
 
 #ifdef CONFIG_MEMORY_HOTPLUG
 
@@ -234,6 +235,7 @@ extern int mem_online_node(int nid);
 extern int add_memory(int nid, u64 start, u64 size);
 extern int arch_add_memory(int nid, u64 start, u64 size);
 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
+extern int offline_memory_block(struct memory_block *mem);
 extern int remove_memory(u64 start, u64 size);
 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
                                                                 int nr_pages);
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index dfc0a6134c7c..7d0797475a47 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1014,11 +1014,42 @@ int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
 
 int remove_memory(u64 start, u64 size)
 {
+        struct memory_block *mem = NULL;
+        struct mem_section *section;
         unsigned long start_pfn, end_pfn;
+        unsigned long pfn, section_nr;
+        int ret;
 
         start_pfn = PFN_DOWN(start);
         end_pfn = start_pfn + PFN_DOWN(size);
-        return __offline_pages(start_pfn, end_pfn, 120 * HZ);
+
+        for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+                section_nr = pfn_to_section_nr(pfn);
+                if (!present_section_nr(section_nr))
+                        continue;
+
+                section = __nr_to_section(section_nr);
+                /* same memblock? */
+                if (mem)
+                        if ((section_nr >= mem->start_section_nr) &&
+                            (section_nr <= mem->end_section_nr))
+                                continue;
+
+                mem = find_memory_block_hinted(section, mem);
+                if (!mem)
+                        continue;
+
+                ret = offline_memory_block(mem);
+                if (ret) {
+                        kobject_put(&mem->dev.kobj);
+                        return ret;
+                }
+        }
+
+        if (mem)
+                kobject_put(&mem->dev.kobj);
+
+        return 0;
 }
 #else
 int offline_pages(unsigned long start_pfn, unsigned long nr_pages)