Merge branch 'next' (accumulated 3.16 merge window patches) into master

Now that 3.15 is released, this merges the 'next' branch into 'master',
bringing us to the normal situation where my 'master' branch is the
merge window.

* accumulated work in next: (6809 commits)
  ufs: sb mutex merge + mutex_destroy
  powerpc: update comments for generic idle conversion
  cris: update comments for generic idle conversion
  idle: remove cpu_idle() forward declarations
  nbd: zero from and len fields in NBD_CMD_DISCONNECT.
  mm: convert some level-less printks to pr_*
  MAINTAINERS: adi-buildroot-devel is moderated
  MAINTAINERS: add linux-api for review of API/ABI changes
  mm/kmemleak-test.c: use pr_fmt for logging
  fs/dlm/debug_fs.c: replace seq_printf by seq_puts
  fs/dlm/lockspace.c: convert simple_str to kstr
  fs/dlm/config.c: convert simple_str to kstr
  mm: mark remap_file_pages() syscall as deprecated
  mm: memcontrol: remove unnecessary memcg argument from soft limit functions
  mm: memcontrol: clean up memcg zoneinfo lookup
  mm/memblock.c: call kmemleak directly from memblock_(alloc|free)
  mm/mempool.c: update the kmemleak stack trace for mempool allocations
  lib/radix-tree.c: update the kmemleak stack trace for radix tree allocations
  mm: introduce kmemleak_update_trace()
  mm/kmemleak.c: use %u to print ->checksum
  ...

1 files changed, 41 insertions, 14 deletions

diff --git a/mm/rmap.c b/mm/rmap.c
index 83bfafa..bf05fc8 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -103,6 +103,7 @@ static inline void anon_vma_free(struct anon_vma *anon_vma)
 	 * LOCK should suffice since the actual taking of the lock must
 	 * happen _before_ what follows.
 	 */
+	might_sleep();
 	if (rwsem_is_locked(&anon_vma->root->rwsem)) {
 		anon_vma_lock_write(anon_vma);
 		anon_vma_unlock_write(anon_vma);
@@ -426,8 +427,9 @@ struct anon_vma *page_get_anon_vma(struct page *page)
 	 * above cannot corrupt).
 	 */
 	if (!page_mapped(page)) {
+		rcu_read_unlock();
 		put_anon_vma(anon_vma);
-		anon_vma = NULL;
+		return NULL;
 	}
 out:
 	rcu_read_unlock();
@@ -477,9 +479,9 @@ struct anon_vma *page_lock_anon_vma_read(struct page *page)
 	}
 
 	if (!page_mapped(page)) {
+		rcu_read_unlock();
 		put_anon_vma(anon_vma);
-		anon_vma = NULL;
-		goto out;
+		return NULL;
 	}
 
 	/* we pinned the anon_vma, its safe to sleep */
@@ -669,7 +671,7 @@ struct page_referenced_arg {
 /*
  * arg: page_referenced_arg will be passed
  */
-int page_referenced_one(struct page *page, struct vm_area_struct *vma,
+static int page_referenced_one(struct page *page, struct vm_area_struct *vma,
 			unsigned long address, void *arg)
 {
 	struct mm_struct *mm = vma->vm_mm;
@@ -986,6 +988,12 @@ void do_page_add_anon_rmap(struct page *page,
 {
 	int first = atomic_inc_and_test(&page->_mapcount);
 	if (first) {
+		/*
+		 * We use the irq-unsafe __{inc|mod}_zone_page_stat because
+		 * these counters are not modified in interrupt context, and
+		 * pte lock(a spinlock) is held, which implies preemption
+		 * disabled.
+		 */
 		if (PageTransHuge(page))
 			__inc_zone_page_state(page,
 					      NR_ANON_TRANSPARENT_HUGEPAGES);
@@ -1024,11 +1032,25 @@ void page_add_new_anon_rmap(struct page *page,
 	__mod_zone_page_state(page_zone(page), NR_ANON_PAGES,
 			hpage_nr_pages(page));
 	__page_set_anon_rmap(page, vma, address, 1);
-	if (!mlocked_vma_newpage(vma, page)) {
+
+	VM_BUG_ON_PAGE(PageLRU(page), page);
+	if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED)) {
 		SetPageActive(page);
 		lru_cache_add(page);
-	} else
-		add_page_to_unevictable_list(page);
+		return;
+	}
+
+	if (!TestSetPageMlocked(page)) {
+		/*
+		 * We use the irq-unsafe __mod_zone_page_stat because this
+		 * counter is not modified from interrupt context, and the pte
+		 * lock is held(spinlock), which implies preemption disabled.
+		 */
+		__mod_zone_page_state(page_zone(page), NR_MLOCK,
+				    hpage_nr_pages(page));
+		count_vm_event(UNEVICTABLE_PGMLOCKED);
+	}
+	add_page_to_unevictable_list(page);
 }
 
 /**
@@ -1077,6 +1099,11 @@ void page_remove_rmap(struct page *page)
 	/*
 	 * Hugepages are not counted in NR_ANON_PAGES nor NR_FILE_MAPPED
 	 * and not charged by memcg for now.
+	 *
+	 * We use the irq-unsafe __{inc|mod}_zone_page_stat because
+	 * these counters are not modified in interrupt context, and
+	 * these counters are not modified in interrupt context, and
+	 * pte lock(a spinlock) is held, which implies preemption disabled.
 	 */
 	if (unlikely(PageHuge(page)))
 		goto out;
@@ -1112,7 +1139,7 @@ out:
 /*
  * @arg: enum ttu_flags will be passed to this argument
  */
-int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
+static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 		     unsigned long address, void *arg)
 {
 	struct mm_struct *mm = vma->vm_mm;
@@ -1135,7 +1162,7 @@ int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 		if (vma->vm_flags & VM_LOCKED)
 			goto out_mlock;
 
-		if (TTU_ACTION(flags) == TTU_MUNLOCK)
+		if (flags & TTU_MUNLOCK)
 			goto out_unmap;
 	}
 	if (!(flags & TTU_IGNORE_ACCESS)) {
@@ -1203,7 +1230,7 @@ int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 			 * pte. do_swap_page() will wait until the migration
 			 * pte is removed and then restart fault handling.
 			 */
-			BUG_ON(TTU_ACTION(flags) != TTU_MIGRATION);
+			BUG_ON(!(flags & TTU_MIGRATION));
 			entry = make_migration_entry(page, pte_write(pteval));
 		}
 		swp_pte = swp_entry_to_pte(entry);
@@ -1212,7 +1239,7 @@ int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 		set_pte_at(mm, address, pte, swp_pte);
 		BUG_ON(pte_file(*pte));
 	} else if (IS_ENABLED(CONFIG_MIGRATION) &&
-		   (TTU_ACTION(flags) == TTU_MIGRATION)) {
+		   (flags & TTU_MIGRATION)) {
 		/* Establish migration entry for a file page */
 		swp_entry_t entry;
 		entry = make_migration_entry(page, pte_write(pteval));
@@ -1225,7 +1252,7 @@ int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 
 out_unmap:
 	pte_unmap_unlock(pte, ptl);
-	if (ret != SWAP_FAIL)
+	if (ret != SWAP_FAIL && !(flags & TTU_MUNLOCK))
 		mmu_notifier_invalidate_page(mm, address);
 out:
 	return ret;
@@ -1359,7 +1386,7 @@ static int try_to_unmap_cluster(unsigned long cursor, unsigned int *mapcount,
 		if (page->index != linear_page_index(vma, address)) {
 			pte_t ptfile = pgoff_to_pte(page->index);
 			if (pte_soft_dirty(pteval))
-				pte_file_mksoft_dirty(ptfile);
+				ptfile = pte_file_mksoft_dirty(ptfile);
 			set_pte_at(mm, address, pte, ptfile);
 		}
 
@@ -1512,7 +1539,7 @@ int try_to_unmap(struct page *page, enum ttu_flags flags)
 	 * locking requirements of exec(), migration skips
 	 * temporary VMAs until after exec() completes.
 	 */
-	if (flags & TTU_MIGRATION && !PageKsm(page) && PageAnon(page))
+	if ((flags & TTU_MIGRATION) && !PageKsm(page) && PageAnon(page))
 		rwc.invalid_vma = invalid_migration_vma;
 
 	ret = rmap_walk(page, &rwc);