memory-hotplug: implement register_page_bootmem_info_section of sparse-vmemmap

For removing memmap region of sparse-vmemmap which is allocated bootmem,
memmap region of sparse-vmemmap needs to be registered by
get_page_bootmem().  So the patch searches pages of virtual mapping and
registers the pages by get_page_bootmem().

NOTE: register_page_bootmem_memmap() is not implemented for ia64,
      ppc, s390, and sparc.  So introduce CONFIG_HAVE_BOOTMEM_INFO_NODE
      and revert register_page_bootmem_info_node() when platform doesn't
      support it.

      It's implemented by adding a new Kconfig option named
      CONFIG_HAVE_BOOTMEM_INFO_NODE, which will be automatically selected
      by memory-hotplug feature fully supported archs(currently only on
      x86_64).

      Since we have 2 config options called MEMORY_HOTPLUG and
      MEMORY_HOTREMOVE used for memory hot-add and hot-remove separately,
      and codes in function register_page_bootmem_info_node() are only
      used for collecting infomation for hot-remove, so reside it under
      MEMORY_HOTREMOVE.

      Besides page_isolation.c selected by MEMORY_ISOLATION under
      MEMORY_HOTPLUG is also such case, move it too.

[mhocko@suse.cz: put register_page_bootmem_memmap inside CONFIG_MEMORY_HOTPLUG_SPARSE]
[linfeng@cn.fujitsu.com: introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node()]
[mhocko@suse.cz: remove the arch specific functions without any implementation]
[linfeng@cn.fujitsu.com: mm/Kconfig: move auto selects from MEMORY_HOTPLUG to MEMORY_HOTREMOVE as needed]
[rientjes@google.com: fix defined but not used warning]
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Reviewed-by: Wu Jianguo <wujianguo@huawei.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Jianguo Wu <wujianguo@huawei.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Lin Feng <linfeng@cn.fujitsu.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 7 deletions

diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 31a563bbd936..4d523fe75ba1 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -174,17 +174,16 @@ static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
 #endif /* CONFIG_NUMA */
 #endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
 
-#ifdef CONFIG_SPARSEMEM_VMEMMAP
+#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
+extern void register_page_bootmem_info_node(struct pglist_data *pgdat);
+#else
 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
 {
 }
-static inline void put_page_bootmem(struct page *page)
-{
-}
-#else
-extern void register_page_bootmem_info_node(struct pglist_data *pgdat);
-extern void put_page_bootmem(struct page *page);
 #endif
+extern void put_page_bootmem(struct page *page);
+extern void get_page_bootmem(unsigned long ingo, struct page *page,
+			     unsigned long type);
 
 /*
  * Lock for memory hotplug guarantees 1) all callbacks for memory hotplug