Merge branch 'akpm' (patchbomb from Andrew) into next

Merge misc updates from Andrew Morton:

 - a few fixes for 3.16.  Cc'ed to stable so they'll get there somehow.

 - various misc fixes and cleanups

 - most of the ocfs2 queue.  Review is slow...

 - most of MM.  The MM queue is pretty huge this time, but not much in
   the way of feature work.

 - some tweaks under kernel/

 - printk maintenance work

 - updates to lib/

 - checkpatch updates

 - tweaks to init/

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (276 commits)
  fs/autofs4/dev-ioctl.c: add __init to autofs_dev_ioctl_init
  fs/ncpfs/getopt.c: replace simple_strtoul by kstrtoul
  init/main.c: remove an ifdef
  kthreads: kill CLONE_KERNEL, change kernel_thread(kernel_init) to avoid CLONE_SIGHAND
  init/main.c: add initcall_blacklist kernel parameter
  init/main.c: don't use pr_debug()
  fs/binfmt_flat.c: make old_reloc() static
  fs/binfmt_elf.c: fix bool assignements
  fs/efs: convert printk(KERN_DEBUG to pr_debug
  fs/efs: add pr_fmt / use __func__
  fs/efs: convert printk to pr_foo()
  scripts/checkpatch.pl: device_initcall is not the only __initcall substitute
  checkpatch: check stable email address
  checkpatch: warn on unnecessary void function return statements
  checkpatch: prefer kstrto<foo> to sscanf(buf, "%<lhuidx>", &bar);
  checkpatch: add warning for kmalloc/kzalloc with multiply
  checkpatch: warn on #defines ending in semicolon
  checkpatch: make --strict a default for files in drivers/net and net/
  checkpatch: always warn on missing blank line after variable declaration block
  checkpatch: fix wildcard DT compatible string checking
  ...

1 files changed, 45 insertions, 18 deletions

diff --git a/mm/migrate.c b/mm/migrate.c
index bed48809e5d0..63f0cd559999 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -938,8 +938,9 @@ out:
  * Obtain the lock on page, remove all ptes and migrate the page
  * to the newly allocated page in newpage.
  */
-static int unmap_and_move(new_page_t get_new_page, unsigned long private,
-			struct page *page, int force, enum migrate_mode mode)
+static int unmap_and_move(new_page_t get_new_page, free_page_t put_new_page,
+			unsigned long private, struct page *page, int force,
+			enum migrate_mode mode)
 {
 	int rc = 0;
 	int *result = NULL;
@@ -983,11 +984,17 @@ out:
 				page_is_file_cache(page));
 		putback_lru_page(page);
 	}
+
 	/*
-	 * Move the new page to the LRU. If migration was not successful
-	 * then this will free the page.
+	 * If migration was not successful and there's a freeing callback, use
+	 * it.  Otherwise, putback_lru_page() will drop the reference grabbed
+	 * during isolation.
 	 */
-	putback_lru_page(newpage);
+	if (rc != MIGRATEPAGE_SUCCESS && put_new_page)
+		put_new_page(newpage, private);
+	else
+		putback_lru_page(newpage);
+
 	if (result) {
 		if (rc)
 			*result = rc;
@@ -1016,8 +1023,9 @@ out:
  * will wait in the page fault for migration to complete.
  */
 static int unmap_and_move_huge_page(new_page_t get_new_page,
-				unsigned long private, struct page *hpage,
-				int force, enum migrate_mode mode)
+				free_page_t put_new_page, unsigned long private,
+				struct page *hpage, int force,
+				enum migrate_mode mode)
 {
 	int rc = 0;
 	int *result = NULL;
@@ -1031,7 +1039,7 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
 	 * tables or check whether the hugepage is pmd-based or not before
 	 * kicking migration.
 	 */
-	if (!hugepage_migration_support(page_hstate(hpage))) {
+	if (!hugepage_migration_supported(page_hstate(hpage))) {
 		putback_active_hugepage(hpage);
 		return -ENOSYS;
 	}
@@ -1056,20 +1064,30 @@ static int unmap_and_move_huge_page(new_page_t get_new_page,
 	if (!page_mapped(hpage))
 		rc = move_to_new_page(new_hpage, hpage, 1, mode);
 
-	if (rc)
+	if (rc != MIGRATEPAGE_SUCCESS)
 		remove_migration_ptes(hpage, hpage);
 
 	if (anon_vma)
 		put_anon_vma(anon_vma);
 
-	if (!rc)
+	if (rc == MIGRATEPAGE_SUCCESS)
 		hugetlb_cgroup_migrate(hpage, new_hpage);
 
 	unlock_page(hpage);
 out:
 	if (rc != -EAGAIN)
 		putback_active_hugepage(hpage);
-	put_page(new_hpage);
+
+	/*
+	 * If migration was not successful and there's a freeing callback, use
+	 * it.  Otherwise, put_page() will drop the reference grabbed during
+	 * isolation.
+	 */
+	if (rc != MIGRATEPAGE_SUCCESS && put_new_page)
+		put_new_page(new_hpage, private);
+	else
+		put_page(new_hpage);
+
 	if (result) {
 		if (rc)
 			*result = rc;
@@ -1086,6 +1104,8 @@ out:
  * @from:		The list of pages to be migrated.
  * @get_new_page:	The function used to allocate free pages to be used
  *			as the target of the page migration.
+ * @put_new_page:	The function used to free target pages if migration
+ *			fails, or NULL if no special handling is necessary.
  * @private:		Private data to be passed on to get_new_page()
  * @mode:		The migration mode that specifies the constraints for
  *			page migration, if any.
@@ -1099,7 +1119,8 @@ out:
  * Returns the number of pages that were not migrated, or an error code.
  */
 int migrate_pages(struct list_head *from, new_page_t get_new_page,
-		unsigned long private, enum migrate_mode mode, int reason)
+		free_page_t put_new_page, unsigned long private,
+		enum migrate_mode mode, int reason)
 {
 	int retry = 1;
 	int nr_failed = 0;
@@ -1121,10 +1142,11 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page,
 
 			if (PageHuge(page))
 				rc = unmap_and_move_huge_page(get_new_page,
-						private, page, pass > 2, mode);
+						put_new_page, private, page,
+						pass > 2, mode);
 			else
-				rc = unmap_and_move(get_new_page, private,
-						page, pass > 2, mode);
+				rc = unmap_and_move(get_new_page, put_new_page,
+						private, page, pass > 2, mode);
 
 			switch(rc) {
 			case -ENOMEM:
@@ -1273,7 +1295,7 @@ set_status:
 
 	err = 0;
 	if (!list_empty(&pagelist)) {
-		err = migrate_pages(&pagelist, new_page_node,
+		err = migrate_pages(&pagelist, new_page_node, NULL,
 				(unsigned long)pm, MIGRATE_SYNC, MR_SYSCALL);
 		if (err)
 			putback_movable_pages(&pagelist);
@@ -1729,7 +1751,8 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
 
 	list_add(&page->lru, &migratepages);
 	nr_remaining = migrate_pages(&migratepages, alloc_misplaced_dst_page,
-				     node, MIGRATE_ASYNC, MR_NUMA_MISPLACED);
+				     NULL, node, MIGRATE_ASYNC,
+				     MR_NUMA_MISPLACED);
 	if (nr_remaining) {
 		if (!list_empty(&migratepages)) {
 			list_del(&page->lru);
@@ -1852,7 +1875,7 @@ fail_putback:
 	 * guarantee the copy is visible before the pagetable update.
 	 */
 	flush_cache_range(vma, mmun_start, mmun_end);
-	page_add_new_anon_rmap(new_page, vma, mmun_start);
+	page_add_anon_rmap(new_page, vma, mmun_start);
 	pmdp_clear_flush(vma, mmun_start, pmd);
 	set_pmd_at(mm, mmun_start, pmd, entry);
 	flush_tlb_range(vma, mmun_start, mmun_end);
@@ -1877,6 +1900,10 @@ fail_putback:
 	spin_unlock(ptl);
 	mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
 
+	/* Take an "isolate" reference and put new page on the LRU. */
+	get_page(new_page);
+	putback_lru_page(new_page);
+
 	unlock_page(new_page);
 	unlock_page(page);
 	put_page(page);			/* Drop the rmap reference */