Merge branch 'akpm' (patches from Andrew Morton)

Merge first patch-bomb from Andrew Morton:
 - Some pidns/fork/exec tweaks
 - OCFS2 updates
 - Most of MM - there remain quite a few memcg parts which depend on
   pending core cgroups changes.  Which might have been already merged -
   I'll check tomorrow...
 - Various misc stuff all over the place
 - A few block bits which I never got around to sending to Jens -
   relatively minor things.
 - MAINTAINERS maintenance
 - A small number of lib/ updates
 - checkpatch updates
 - epoll
 - firmware/dmi-scan
 - Some kprobes work for S390
 - drivers/rtc updates
 - hfsplus feature work
 - vmcore feature work
 - rbtree upgrades
 - AOE updates
 - pktcdvd cleanups
 - PPS
 - memstick
 - w1
 - New "inittmpfs" feature, which does the obvious
 - More IPC work from Davidlohr.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (303 commits)
  lz4: fix compression/decompression signedness mismatch
  ipc: drop ipc_lock_check
  ipc, shm: drop shm_lock_check
  ipc: drop ipc_lock_by_ptr
  ipc, shm: guard against non-existant vma in shmdt(2)
  ipc: document general ipc locking scheme
  ipc,msg: drop msg_unlock
  ipc: rename ids->rw_mutex
  ipc,shm: shorten critical region for shmat
  ipc,shm: cleanup do_shmat pasta
  ipc,shm: shorten critical region for shmctl
  ipc,shm: make shmctl_nolock lockless
  ipc,shm: introduce shmctl_nolock
  ipc: drop ipcctl_pre_down
  ipc,shm: shorten critical region in shmctl_down
  ipc,shm: introduce lockless functions to obtain the ipc object
  initmpfs: use initramfs if rootfstype= or root= specified
  initmpfs: make rootfs use tmpfs when CONFIG_TMPFS enabled
  initmpfs: move rootfs code from fs/ramfs/ to init/
  initmpfs: move bdi setup from init_rootfs to init_ramfs
  ...

1 files changed, 33 insertions, 30 deletions

diff --git a/mm/migrate.c b/mm/migrate.c
index 6f0c24438bb..b7ded7eafe3 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -100,6 +100,10 @@ void putback_movable_pages(struct list_head *l)
 	struct page *page2;
 
 	list_for_each_entry_safe(page, page2, l, lru) {
+		if (unlikely(PageHuge(page))) {
+			putback_active_hugepage(page);
+			continue;
+		}
 		list_del(&page->lru);
 		dec_zone_page_state(page, NR_ISOLATED_ANON +
 				page_is_file_cache(page));
@@ -945,6 +949,16 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
 	struct page *new_hpage = get_new_page(hpage, private, &result);
 	struct anon_vma *anon_vma = NULL;
 
+	/*
+	 * Movability of hugepages depends on architectures and hugepage size.
+	 * This check is necessary because some callers of hugepage migration
+	 * like soft offline and memory hotremove don't walk through page
+	 * tables or check whether the hugepage is pmd-based or not before
+	 * kicking migration.
+	 */
+	if (!hugepage_migration_support(page_hstate(hpage)))
+		return -ENOSYS;
+
 	if (!new_hpage)
 		return -ENOMEM;
 
@@ -975,6 +989,8 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
 
 	unlock_page(hpage);
 out:
+	if (rc != -EAGAIN)
+		putback_active_hugepage(hpage);
 	put_page(new_hpage);
 	if (result) {
 		if (rc)
@@ -1025,7 +1041,11 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page,
 		list_for_each_entry_safe(page, page2, from, lru) {
 			cond_resched();
 
-			rc = unmap_and_move(get_new_page, private,
+			if (PageHuge(page))
+				rc = unmap_and_move_huge_page(get_new_page,
+						private, page, pass > 2, mode);
+			else
+				rc = unmap_and_move(get_new_page, private,
 						page, pass > 2, mode);
 
 			switch(rc) {
@@ -1058,32 +1078,6 @@ out:
 	return rc;
 }
 
-int migrate_huge_page(struct page *hpage, new_page_t get_new_page,
-		      unsigned long private, enum migrate_mode mode)
-{
-	int pass, rc;
-
-	for (pass = 0; pass < 10; pass++) {
-		rc = unmap_and_move_huge_page(get_new_page, private,
-						hpage, pass > 2, mode);
-		switch (rc) {
-		case -ENOMEM:
-			goto out;
-		case -EAGAIN:
-			/* try again */
-			cond_resched();
-			break;
-		case MIGRATEPAGE_SUCCESS:
-			goto out;
-		default:
-			rc = -EIO;
-			goto out;
-		}
-	}
-out:
-	return rc;
-}
-
 #ifdef CONFIG_NUMA
 /*
  * Move a list of individual pages
@@ -1108,7 +1102,11 @@ static struct page *new_page_node(struct page *p, unsigned long private,
 
 	*result = &pm->status;
 
-	return alloc_pages_exact_node(pm->node,
+	if (PageHuge(p))
+		return alloc_huge_page_node(page_hstate(compound_head(p)),
+					pm->node);
+	else
+		return alloc_pages_exact_node(pm->node,
 				GFP_HIGHUSER_MOVABLE | GFP_THISNODE, 0);
 }
 
@@ -1168,6 +1166,11 @@ static int do_move_page_to_node_array(struct mm_struct *mm,
 				!migrate_all)
 			goto put_and_set;
 
+		if (PageHuge(page)) {
+			isolate_huge_page(page, &pagelist);
+			goto put_and_set;
+		}
+
 		err = isolate_lru_page(page);
 		if (!err) {
 			list_add_tail(&page->lru, &pagelist);
@@ -1190,7 +1193,7 @@ set_status:
 		err = migrate_pages(&pagelist, new_page_node,
 				(unsigned long)pm, MIGRATE_SYNC, MR_SYSCALL);
 		if (err)
-			putback_lru_pages(&pagelist);
+			putback_movable_pages(&pagelist);
 	}
 
 	up_read(&mm->mmap_sem);
@@ -1468,7 +1471,7 @@ static bool migrate_balanced_pgdat(struct pglist_data *pgdat,
 		if (!populated_zone(zone))
 			continue;
 
-		if (zone->all_unreclaimable)
+		if (!zone_reclaimable(zone))
 			continue;
 
 		/* Avoid waking kswapd by allocating pages_to_migrate pages. */