Merge branch 'akpm' (patches from Andrew)

Merge misc updates from Andrew Morton:
 "Bite-sized chunks this time, to avoid the MTA ratelimiting woes.

   - fs/notify updates

   - ocfs2

   - some of MM"

That laconic "some MM" is mainly the removal of remap_file_pages(),
which is a big simplification of the VM, and which gets rid of a *lot*
of random cruft and special cases because we no longer support the
non-linear mappings that it used.

From a user interface perspective, nothing has changed, because the
remap_file_pages() syscall still exists, it's just done by emulating the
old behavior by creating a lot of individual small mappings instead of
one non-linear one.

The emulation is slower than the old "native" non-linear mappings, but
nobody really uses or cares about remap_file_pages(), and simplifying
the VM is a big advantage.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (78 commits)
  memcg: zap memcg_slab_caches and memcg_slab_mutex
  memcg: zap memcg_name argument of memcg_create_kmem_cache
  memcg: zap __memcg_{charge,uncharge}_slab
  mm/page_alloc.c: place zone_id check before VM_BUG_ON_PAGE check
  mm: hugetlb: fix type of hugetlb_treat_as_movable variable
  mm, hugetlb: remove unnecessary lower bound on sysctl handlers"?
  mm: memory: merge shared-writable dirtying branches in do_wp_page()
  mm: memory: remove ->vm_file check on shared writable vmas
  xtensa: drop _PAGE_FILE and pte_file()-related helpers
  x86: drop _PAGE_FILE and pte_file()-related helpers
  unicore32: drop pte_file()-related helpers
  um: drop _PAGE_FILE and pte_file()-related helpers
  tile: drop pte_file()-related helpers
  sparc: drop pte_file()-related helpers
  sh: drop _PAGE_FILE and pte_file()-related helpers
  score: drop _PAGE_FILE and pte_file()-related helpers
  s390: drop pte_file()-related helpers
  parisc: drop _PAGE_FILE and pte_file()-related helpers
  openrisc: drop _PAGE_FILE and pte_file()-related helpers
  nios2: drop _PAGE_FILE and pte_file()-related helpers
  ...

10 files changed, 49 insertions, 67 deletions

diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index 177d5973b132..129de9204d18 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -474,21 +474,6 @@ static inline pte_t pte_swp_clear_soft_dirty(pte_t pte)
 {
 	return pte;
 }
-
-static inline pte_t pte_file_clear_soft_dirty(pte_t pte)
-{
-       return pte;
-}
-
-static inline pte_t pte_file_mksoft_dirty(pte_t pte)
-{
-       return pte;
-}
-
-static inline int pte_file_soft_dirty(pte_t pte)
-{
-       return 0;
-}
 #endif
 
 #ifndef __HAVE_PFNMAP_TRACKING
diff --git a/include/linux/fs.h b/include/linux/fs.h
index ddd2fa7cefd3..f125b88443bd 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -401,7 +401,6 @@ struct address_space {
 	spinlock_t		tree_lock;	/* and lock protecting it */
 	atomic_t		i_mmap_writable;/* count VM_SHARED mappings */
 	struct rb_root		i_mmap;		/* tree of private and shared mappings */
-	struct list_head	i_mmap_nonlinear;/*list VM_NONLINEAR mappings */
 	struct rw_semaphore	i_mmap_rwsem;	/* protect tree, count, list */
 	/* Protected by tree_lock together with the radix tree */
 	unsigned long		nrpages;	/* number of total pages */
@@ -493,8 +492,7 @@ static inline void i_mmap_unlock_read(struct address_space *mapping)
  */
 static inline int mapping_mapped(struct address_space *mapping)
 {
-	return	!RB_EMPTY_ROOT(&mapping->i_mmap) ||
-		!list_empty(&mapping->i_mmap_nonlinear);
+	return	!RB_EMPTY_ROOT(&mapping->i_mmap);
 }
 
 /*
@@ -2501,8 +2499,6 @@ extern int sb_min_blocksize(struct super_block *, int);
 
 extern int generic_file_mmap(struct file *, struct vm_area_struct *);
 extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
-extern int generic_file_remap_pages(struct vm_area_struct *, unsigned long addr,
-		unsigned long size, pgoff_t pgoff);
 int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
 extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *);
 extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *);
diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h
index 1c804b057fb1..7ee1774edee5 100644
--- a/include/linux/fsnotify.h
+++ b/include/linux/fsnotify.h
@@ -101,8 +101,10 @@ static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir,
 		new_dir_mask |= FS_ISDIR;
 	}
 
-	fsnotify(old_dir, old_dir_mask, old_dir, FSNOTIFY_EVENT_INODE, old_name, fs_cookie);
-	fsnotify(new_dir, new_dir_mask, new_dir, FSNOTIFY_EVENT_INODE, new_name, fs_cookie);
+	fsnotify(old_dir, old_dir_mask, source, FSNOTIFY_EVENT_INODE, old_name,
+		 fs_cookie);
+	fsnotify(new_dir, new_dir_mask, source, FSNOTIFY_EVENT_INODE, new_name,
+		 fs_cookie);
 
 	if (target)
 		fsnotify_link_count(target);
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 431b7fc605c9..7d7856359920 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -86,7 +86,7 @@ void free_huge_page(struct page *page);
 pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud);
 #endif
 
-extern unsigned long hugepages_treat_as_movable;
+extern int hugepages_treat_as_movable;
 extern int sysctl_hugetlb_shm_group;
 extern struct list_head huge_boot_pages;
 
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 7c95af8d552c..fb212e1d700d 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -403,10 +403,9 @@ void memcg_update_array_size(int num_groups);
 struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep);
 void __memcg_kmem_put_cache(struct kmem_cache *cachep);
 
-int __memcg_charge_slab(struct kmem_cache *cachep, gfp_t gfp, int order);
-void __memcg_uncharge_slab(struct kmem_cache *cachep, int order);
-
-int __memcg_cleanup_cache_params(struct kmem_cache *s);
+int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp,
+		      unsigned long nr_pages);
+void memcg_uncharge_kmem(struct mem_cgroup *memcg, unsigned long nr_pages);
 
 /**
  * memcg_kmem_newpage_charge: verify if a new kmem allocation is allowed.
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 237b3ba29225..65db4aee738a 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -138,7 +138,6 @@ extern unsigned int kobjsize(const void *objp);
 #define VM_ACCOUNT	0x00100000	/* Is a VM accounted object */
 #define VM_NORESERVE	0x00200000	/* should the VM suppress accounting */
 #define VM_HUGETLB	0x00400000	/* Huge TLB Page VM */
-#define VM_NONLINEAR	0x00800000	/* Is non-linear (remap_file_pages) */
 #define VM_ARCH_1	0x01000000	/* Architecture-specific flag */
 #define VM_ARCH_2	0x02000000
 #define VM_DONTDUMP	0x04000000	/* Do not include in the core dump */
@@ -206,21 +205,19 @@ extern unsigned int kobjsize(const void *objp);
 extern pgprot_t protection_map[16];
 
 #define FAULT_FLAG_WRITE	0x01	/* Fault was a write access */
-#define FAULT_FLAG_NONLINEAR	0x02	/* Fault was via a nonlinear mapping */
-#define FAULT_FLAG_MKWRITE	0x04	/* Fault was mkwrite of existing pte */
-#define FAULT_FLAG_ALLOW_RETRY	0x08	/* Retry fault if blocking */
-#define FAULT_FLAG_RETRY_NOWAIT	0x10	/* Don't drop mmap_sem and wait when retrying */
-#define FAULT_FLAG_KILLABLE	0x20	/* The fault task is in SIGKILL killable region */
-#define FAULT_FLAG_TRIED	0x40	/* second try */
-#define FAULT_FLAG_USER		0x80	/* The fault originated in userspace */
+#define FAULT_FLAG_MKWRITE	0x02	/* Fault was mkwrite of existing pte */
+#define FAULT_FLAG_ALLOW_RETRY	0x04	/* Retry fault if blocking */
+#define FAULT_FLAG_RETRY_NOWAIT	0x08	/* Don't drop mmap_sem and wait when retrying */
+#define FAULT_FLAG_KILLABLE	0x10	/* The fault task is in SIGKILL killable region */
+#define FAULT_FLAG_TRIED	0x20	/* Second try */
+#define FAULT_FLAG_USER		0x40	/* The fault originated in userspace */
 
 /*
  * vm_fault is filled by the the pagefault handler and passed to the vma's
  * ->fault function. The vma's ->fault is responsible for returning a bitmask
  * of VM_FAULT_xxx flags that give details about how the fault was handled.
  *
- * pgoff should be used in favour of virtual_address, if possible. If pgoff
- * is used, one may implement ->remap_pages to get nonlinear mapping support.
+ * pgoff should be used in favour of virtual_address, if possible.
  */
 struct vm_fault {
 	unsigned int flags;		/* FAULT_FLAG_xxx flags */
@@ -287,10 +284,6 @@ struct vm_operations_struct {
 	struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
 					unsigned long addr);
 #endif
-	/* called by sys_remap_file_pages() to populate non-linear mapping */
-	int (*remap_pages)(struct vm_area_struct *vma, unsigned long addr,
-			   unsigned long size, pgoff_t pgoff);
-
 	/*
 	 * Called by vm_normal_page() for special PTEs to find the
 	 * page for @addr.  This is useful if the default behavior
@@ -454,6 +447,12 @@ static inline struct page *compound_head_by_tail(struct page *tail)
 	return tail;
 }
 
+/*
+ * Since either compound page could be dismantled asynchronously in THP
+ * or we access asynchronously arbitrary positioned struct page, there
+ * would be tail flag race. To handle this race, we should call
+ * smp_rmb() before checking tail flag. compound_head_by_tail() did it.
+ */
 static inline struct page *compound_head(struct page *page)
 {
 	if (unlikely(PageTail(page)))
@@ -462,6 +461,18 @@ static inline struct page *compound_head(struct page *page)
 }
 
 /*
+ * If we access compound page synchronously such as access to
+ * allocated page, there is no need to handle tail flag race, so we can
+ * check tail flag directly without any synchronization primitive.
+ */
+static inline struct page *compound_head_fast(struct page *page)
+{
+	if (unlikely(PageTail(page)))
+		return page->first_page;
+	return page;
+}
+
+/*
  * The atomic page->_mapcount, starts from -1: so that transitions
  * both from it and to it can be tracked, using atomic_inc_and_test
  * and atomic_add_negative(-1).
@@ -539,7 +550,14 @@ static inline void get_page(struct page *page)
 static inline struct page *virt_to_head_page(const void *x)
 {
 	struct page *page = virt_to_page(x);
-	return compound_head(page);
+
+	/*
+	 * We don't need to worry about synchronization of tail flag
+	 * when we call virt_to_head_page() since it is only called for
+	 * already allocated page and this page won't be freed until
+	 * this virt_to_head_page() is finished. So use _fast variant.
+	 */
+	return compound_head_fast(page);
 }
 
 /*
@@ -1129,7 +1147,6 @@ extern void user_shm_unlock(size_t, struct user_struct *);
  * Parameter block passed down to zap_pte_range in exceptional cases.
  */
 struct zap_details {
-	struct vm_area_struct *nonlinear_vma;	/* Check page->index if set */
 	struct address_space *check_mapping;	/* Check page->mapping if set */
 	pgoff_t	first_index;			/* Lowest page->index to unmap */
 	pgoff_t last_index;			/* Highest page->index to unmap */
@@ -1785,12 +1802,6 @@ struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node,
 	for (vma = vma_interval_tree_iter_first(root, start, last);	\
 	     vma; vma = vma_interval_tree_iter_next(vma, start, last))
 
-static inline void vma_nonlinear_insert(struct vm_area_struct *vma,
-					struct list_head *list)
-{
-	list_add_tail(&vma->shared.nonlinear, list);
-}
-
 void anon_vma_interval_tree_insert(struct anon_vma_chain *node,
 				   struct rb_root *root);
 void anon_vma_interval_tree_remove(struct anon_vma_chain *node,
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 6d34aa266a8c..07c8bd3f7b48 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -273,15 +273,11 @@ struct vm_area_struct {
 
 	/*
 	 * For areas with an address space and backing store,
-	 * linkage into the address_space->i_mmap interval tree, or
-	 * linkage of vma in the address_space->i_mmap_nonlinear list.
+	 * linkage into the address_space->i_mmap interval tree.
 	 */
-	union {
-		struct {
-			struct rb_node rb;
-			unsigned long rb_subtree_last;
-		} linear;
-		struct list_head nonlinear;
+	struct {
+		struct rb_node rb;
+		unsigned long rb_subtree_last;
 	} shared;
 
 	/*
diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index d9d7e7e56352..b38f559130d5 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -246,7 +246,6 @@ int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma);
  * arg: passed to rmap_one() and invalid_vma()
  * rmap_one: executed on each vma where page is mapped
  * done: for checking traversing termination condition
- * file_nonlinear: for handling file nonlinear mapping
  * anon_lock: for getting anon_lock by optimized way rather than default
  * invalid_vma: for skipping uninterested vma
  */
@@ -255,7 +254,6 @@ struct rmap_walk_control {
 	int (*rmap_one)(struct page *page, struct vm_area_struct *vma,
 					unsigned long addr, void *arg);
 	int (*done)(struct page *page);
-	int (*file_nonlinear)(struct page *, struct address_space *, void *arg);
 	struct anon_vma *(*anon_lock)(struct page *page);
 	bool (*invalid_vma)(struct vm_area_struct *vma, void *arg);
 };
diff --git a/include/linux/slab.h b/include/linux/slab.h
index 9a139b637069..2e3b448cfa2d 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -116,9 +116,8 @@ struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
 			unsigned long,
 			void (*)(void *));
 #ifdef CONFIG_MEMCG_KMEM
-struct kmem_cache *memcg_create_kmem_cache(struct mem_cgroup *,
-					   struct kmem_cache *,
-					   const char *);
+void memcg_create_kmem_cache(struct mem_cgroup *, struct kmem_cache *);
+void memcg_destroy_kmem_caches(struct mem_cgroup *);
 #endif
 void kmem_cache_destroy(struct kmem_cache *);
 int kmem_cache_shrink(struct kmem_cache *);
@@ -491,7 +490,6 @@ static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
  * Child caches will hold extra metadata needed for its operation. Fields are:
  *
  * @memcg: pointer to the memcg this cache belongs to
- * @list: list_head for the list of all caches in this memcg
  * @root_cache: pointer to the global, root cache, this cache was derived from
  */
 struct memcg_cache_params {
@@ -503,7 +501,6 @@ struct memcg_cache_params {
 		};
 		struct {
 			struct mem_cgroup *memcg;
-			struct list_head list;
 			struct kmem_cache *root_cache;
 		};
 	};
diff --git a/include/linux/swapops.h b/include/linux/swapops.h
index 6adfb7bfbf44..50cbc876be56 100644
--- a/include/linux/swapops.h
+++ b/include/linux/swapops.h
@@ -54,7 +54,7 @@ static inline pgoff_t swp_offset(swp_entry_t entry)
 /* check whether a pte points to a swap entry */
 static inline int is_swap_pte(pte_t pte)
 {
-	return !pte_none(pte) && !pte_present_nonuma(pte) && !pte_file(pte);
+	return !pte_none(pte) && !pte_present_nonuma(pte);
 }
 #endif
 
@@ -66,7 +66,6 @@ static inline swp_entry_t pte_to_swp_entry(pte_t pte)
 {
 	swp_entry_t arch_entry;
 
-	BUG_ON(pte_file(pte));
 	if (pte_swp_soft_dirty(pte))
 		pte = pte_swp_clear_soft_dirty(pte);
 	arch_entry = __pte_to_swp_entry(pte);
@@ -82,7 +81,6 @@ static inline pte_t swp_entry_to_pte(swp_entry_t entry)
 	swp_entry_t arch_entry;
 
 	arch_entry = __swp_entry(swp_type(entry), swp_offset(entry));
-	BUG_ON(pte_file(__swp_entry_to_pte(arch_entry)));
 	return __swp_entry_to_pte(arch_entry);
 }