memory hotplug: rearrange memory hotplug notifier

Current memory notifier has some defects yet.  (Fortunately, nothing uses
it.) This patch is to fix and rearrange for them.

  - Add information of start_pfn, nr_pages, and node id if node status is
    changes from/to memoryless node for callback functions.
    Callbacks can't do anything without those information.
  - Add notification going-online status.
    It is necessary for creating per node structure before the node's
    pages are available.
  - Move GOING_OFFLINE status notification after page isolation.
    It is good place for return memory like cache for callback,
    because returned page is not used again.
  - Make CANCEL events for rollingback when error occurs.
  - Delete MEM_MAPPING_INVALID notification. It will be not used.
  - Fix compile error of (un)register_memory_notifier().

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 8 deletions

diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index c41d0728efe2..7868707c7eda 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -137,7 +137,7 @@ static ssize_t show_mem_state(struct sys_device *dev, char *buf)
         return len;
 }
 
-static inline int memory_notify(unsigned long val, void *v)
+int memory_notify(unsigned long val, void *v)
 {
         return blocking_notifier_call_chain(&memory_chain, val, v);
 }
@@ -183,7 +183,6 @@ memory_block_action(struct memory_block *mem, unsigned long action)
                         break;
                 case MEM_OFFLINE:
                         mem->state = MEM_GOING_OFFLINE;
-                        memory_notify(MEM_GOING_OFFLINE, NULL);
                         start_paddr = page_to_pfn(first_page) << PAGE_SHIFT;
                         ret = remove_memory(start_paddr,
                                             PAGES_PER_SECTION << PAGE_SHIFT);
@@ -191,7 +190,6 @@ memory_block_action(struct memory_block *mem, unsigned long action)
                                 mem->state = old_state;
                                 break;
                         }
-                        memory_notify(MEM_MAPPING_INVALID, NULL);
                         break;
                 default:
                         printk(KERN_WARNING "%s(%p, %ld) unknown action: %ld\n",
@@ -199,11 +197,6 @@ memory_block_action(struct memory_block *mem, unsigned long action)
                         WARN_ON(1);
                         ret = -EINVAL;
         }
-        /*
-         * For now, only notify on successful memory operations
-         */
-        if (!ret)
-                memory_notify(action, NULL);
 
         return ret;
 }