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>
diff --git a/include/linux/memory.h b/include/linux/memory.h
index 654ef55..ec376e4 100644
--- a/include/linux/memory.h
+++ b/include/linux/memory.h
@@ -41,18 +41,15 @@
#define MEM_ONLINE (1<<0) /* exposed to userspace */
#define MEM_GOING_OFFLINE (1<<1) /* exposed to userspace */
#define MEM_OFFLINE (1<<2) /* exposed to userspace */
+#define MEM_GOING_ONLINE (1<<3)
+#define MEM_CANCEL_ONLINE (1<<4)
+#define MEM_CANCEL_OFFLINE (1<<5)
-/*
- * All of these states are currently kernel-internal for notifying
- * kernel components and architectures.
- *
- * For MEM_MAPPING_INVALID, all notifier chains with priority >0
- * are called before pfn_to_page() becomes invalid. The priority=0
- * entry is reserved for the function that actually makes
- * pfn_to_page() stop working. Any notifiers that want to be called
- * after that should have priority <0.
- */
-#define MEM_MAPPING_INVALID (1<<3)
+struct memory_notify {
+ unsigned long start_pfn;
+ unsigned long nr_pages;
+ int status_change_nid;
+};
struct notifier_block;
struct mem_section;
@@ -69,12 +66,18 @@
static inline void unregister_memory_notifier(struct notifier_block *nb)
{
}
+static inline int memory_notify(unsigned long val, void *v)
+{
+ return 0;
+}
#else
+extern int register_memory_notifier(struct notifier_block *nb);
+extern void unregister_memory_notifier(struct notifier_block *nb);
extern int register_new_memory(struct mem_section *);
extern int unregister_memory_section(struct mem_section *);
extern int memory_dev_init(void);
extern int remove_memory_block(unsigned long, struct mem_section *, int);
-
+extern int memory_notify(unsigned long val, void *v);
#define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION<<PAGE_SHIFT)