Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:

 - a bit more MM

 - procfs updates

 - dynamic-debug fixes

 - lib/ updates

 - checkpatch

 - epoll

 - nilfs2

 - signals

 - rapidio

 - PID management cleanup and optimization

 - kcov updates

 - sysvipc updates

 - quite a few misc things all over the place

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits)
  EXPERT Kconfig menu: fix broken EXPERT menu
  include/asm-generic/topology.h: remove unused parent_node() macro
  arch/tile/include/asm/topology.h: remove unused parent_node() macro
  arch/sparc/include/asm/topology_64.h: remove unused parent_node() macro
  arch/sh/include/asm/topology.h: remove unused parent_node() macro
  arch/ia64/include/asm/topology.h: remove unused parent_node() macro
  drivers/pcmcia/sa1111_badge4.c: avoid unused function warning
  mm: add infrastructure for get_user_pages_fast() benchmarking
  sysvipc: make get_maxid O(1) again
  sysvipc: properly name ipc_addid() limit parameter
  sysvipc: duplicate lock comments wrt ipc_addid()
  sysvipc: unteach ids->next_id for !CHECKPOINT_RESTORE
  initramfs: use time64_t timestamps
  drivers/watchdog: make use of devm_register_reboot_notifier()
  kernel/reboot.c: add devm_register_reboot_notifier()
  kcov: update documentation
  Makefile: support flag -fsanitizer-coverage=trace-cmp
  kcov: support comparison operands collection
  kcov: remove pointless current != NULL check
  kernel/panic.c: add TAINT_AUX
  ...

18 files changed, 147 insertions, 152 deletions

diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c
index 4ac49d038bf3..8fc41705c7cd 100644
--- a/fs/autofs4/waitq.c
+++ b/fs/autofs4/waitq.c
@@ -81,7 +81,8 @@ static int autofs4_write(struct autofs_sb_info *sbi,
 		spin_unlock_irqrestore(&current->sighand->siglock, flags);
 	}
 
-	return (bytes > 0);
+	/* if 'wr' returned 0 (impossible) we assume -EIO (safe) */
+	return bytes == 0 ? 0 : wr < 0 ? wr : -EIO;
 }
 
 static void autofs4_notify_daemon(struct autofs_sb_info *sbi,
@@ -95,6 +96,7 @@ static void autofs4_notify_daemon(struct autofs_sb_info *sbi,
 	} pkt;
 	struct file *pipe = NULL;
 	size_t pktsz;
+	int ret;
 
 	pr_debug("wait id = 0x%08lx, name = %.*s, type=%d\n",
 		 (unsigned long) wq->wait_queue_token,
@@ -169,7 +171,18 @@ static void autofs4_notify_daemon(struct autofs_sb_info *sbi,
 	mutex_unlock(&sbi->wq_mutex);
 
 	if (autofs4_write(sbi, pipe, &pkt, pktsz))
+	switch (ret = autofs4_write(sbi, pipe, &pkt, pktsz)) {
+	case 0:
+		break;
+	case -ENOMEM:
+	case -ERESTARTSYS:
+		/* Just fail this one */
+		autofs4_wait_release(sbi, wq->wait_queue_token, ret);
+		break;
+	default:
 		autofs4_catatonic_mode(sbi);
+		break;
+	}
 	fput(pipe);
 }
 
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 396a3c075fd4..afd548ebc328 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -276,12 +276,6 @@ static DEFINE_MUTEX(epmutex);
 /* Used to check for epoll file descriptor inclusion loops */
 static struct nested_calls poll_loop_ncalls;
 
-/* Used for safe wake up implementation */
-static struct nested_calls poll_safewake_ncalls;
-
-/* Used to call file's f_op->poll() under the nested calls boundaries */
-static struct nested_calls poll_readywalk_ncalls;
-
 /* Slab cache used to allocate "struct epitem" */
 static struct kmem_cache *epi_cache __read_mostly;
 
@@ -551,40 +545,21 @@ out_unlock:
  * this special case of epoll.
  */
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
-static inline void ep_wake_up_nested(wait_queue_head_t *wqueue,
-				     unsigned long events, int subclass)
+
+static struct nested_calls poll_safewake_ncalls;
+
+static int ep_poll_wakeup_proc(void *priv, void *cookie, int call_nests)
 {
 	unsigned long flags;
+	wait_queue_head_t *wqueue = (wait_queue_head_t *)cookie;
 
-	spin_lock_irqsave_nested(&wqueue->lock, flags, subclass);
-	wake_up_locked_poll(wqueue, events);
+	spin_lock_irqsave_nested(&wqueue->lock, flags, call_nests + 1);
+	wake_up_locked_poll(wqueue, POLLIN);
 	spin_unlock_irqrestore(&wqueue->lock, flags);
-}
-#else
-static inline void ep_wake_up_nested(wait_queue_head_t *wqueue,
-				     unsigned long events, int subclass)
-{
-	wake_up_poll(wqueue, events);
-}
-#endif
 
-static int ep_poll_wakeup_proc(void *priv, void *cookie, int call_nests)
-{
-	ep_wake_up_nested((wait_queue_head_t *) cookie, POLLIN,
-			  1 + call_nests);
 	return 0;
 }
 
-/*
- * Perform a safe wake up of the poll wait list. The problem is that
- * with the new callback'd wake up system, it is possible that the
- * poll callback is reentered from inside the call to wake_up() done
- * on the poll wait queue head. The rule is that we cannot reenter the
- * wake up code from the same task more than EP_MAX_NESTS times,
- * and we cannot reenter the same wait queue head at all. This will
- * enable to have a hierarchy of epoll file descriptor of no more than
- * EP_MAX_NESTS deep.
- */
 static void ep_poll_safewake(wait_queue_head_t *wq)
 {
 	int this_cpu = get_cpu();
@@ -595,6 +570,15 @@ static void ep_poll_safewake(wait_queue_head_t *wq)
 	put_cpu();
 }
 
+#else
+
+static void ep_poll_safewake(wait_queue_head_t *wq)
+{
+	wake_up_poll(wq, POLLIN);
+}
+
+#endif
+
 static void ep_remove_wait_queue(struct eppoll_entry *pwq)
 {
 	wait_queue_head_t *whead;
@@ -880,11 +864,33 @@ static int ep_eventpoll_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static inline unsigned int ep_item_poll(struct epitem *epi, poll_table *pt)
+static int ep_read_events_proc(struct eventpoll *ep, struct list_head *head,
+			       void *priv);
+static void ep_ptable_queue_proc(struct file *file, wait_queue_head_t *whead,
+				 poll_table *pt);
+
+/*
+ * Differs from ep_eventpoll_poll() in that internal callers already have
+ * the ep->mtx so we need to start from depth=1, such that mutex_lock_nested()
+ * is correctly annotated.
+ */
+static unsigned int ep_item_poll(struct epitem *epi, poll_table *pt, int depth)
 {
+	struct eventpoll *ep;
+	bool locked;
+
 	pt->_key = epi->event.events;
+	if (!is_file_epoll(epi->ffd.file))
+		return epi->ffd.file->f_op->poll(epi->ffd.file, pt) &
+		       epi->event.events;
+
+	ep = epi->ffd.file->private_data;
+	poll_wait(epi->ffd.file, &ep->poll_wait, pt);
+	locked = pt && (pt->_qproc == ep_ptable_queue_proc);
 
-	return epi->ffd.file->f_op->poll(epi->ffd.file, pt) & epi->event.events;
+	return ep_scan_ready_list(epi->ffd.file->private_data,
+				  ep_read_events_proc, &depth, depth,
+				  locked) & epi->event.events;
 }
 
 static int ep_read_events_proc(struct eventpoll *ep, struct list_head *head,
@@ -892,13 +898,15 @@ static int ep_read_events_proc(struct eventpoll *ep, struct list_head *head,
 {
 	struct epitem *epi, *tmp;
 	poll_table pt;
+	int depth = *(int *)priv;
 
 	init_poll_funcptr(&pt, NULL);
+	depth++;
 
 	list_for_each_entry_safe(epi, tmp, head, rdllink) {
-		if (ep_item_poll(epi, &pt))
+		if (ep_item_poll(epi, &pt, depth)) {
 			return POLLIN | POLLRDNORM;
-		else {
+		} else {
 			/*
 			 * Item has been dropped into the ready list by the poll
 			 * callback, but it's not actually ready, as far as
@@ -912,48 +920,20 @@ static int ep_read_events_proc(struct eventpoll *ep, struct list_head *head,
 	return 0;
 }
 
-static void ep_ptable_queue_proc(struct file *file, wait_queue_head_t *whead,
-				 poll_table *pt);
-
-struct readyevents_arg {
-	struct eventpoll *ep;
-	bool locked;
-};
-
-static int ep_poll_readyevents_proc(void *priv, void *cookie, int call_nests)
-{
-	struct readyevents_arg *arg = priv;
-
-	return ep_scan_ready_list(arg->ep, ep_read_events_proc, NULL,
-				  call_nests + 1, arg->locked);
-}
-
 static unsigned int ep_eventpoll_poll(struct file *file, poll_table *wait)
 {
-	int pollflags;
 	struct eventpoll *ep = file->private_data;
-	struct readyevents_arg arg;
-
-	/*
-	 * During ep_insert() we already hold the ep->mtx for the tfile.
-	 * Prevent re-aquisition.
-	 */
-	arg.locked = wait && (wait->_qproc == ep_ptable_queue_proc);
-	arg.ep = ep;
+	int depth = 0;
 
 	/* Insert inside our poll wait queue */
 	poll_wait(file, &ep->poll_wait, wait);
 
 	/*
 	 * Proceed to find out if wanted events are really available inside
-	 * the ready list. This need to be done under ep_call_nested()
-	 * supervision, since the call to f_op->poll() done on listed files
-	 * could re-enter here.
+	 * the ready list.
 	 */
-	pollflags = ep_call_nested(&poll_readywalk_ncalls, EP_MAX_NESTS,
-				   ep_poll_readyevents_proc, &arg, ep, current);
-
-	return pollflags != -1 ? pollflags : 0;
+	return ep_scan_ready_list(ep, ep_read_events_proc,
+				  &depth, depth, false);
 }
 
 #ifdef CONFIG_PROC_FS
@@ -1472,7 +1452,7 @@ static int ep_insert(struct eventpoll *ep, struct epoll_event *event,
 	 * this operation completes, the poll callback can start hitting
 	 * the new item.
 	 */
-	revents = ep_item_poll(epi, &epq.pt);
+	revents = ep_item_poll(epi, &epq.pt, 1);
 
 	/*
 	 * We have to check if something went wrong during the poll wait queue
@@ -1606,7 +1586,7 @@ static int ep_modify(struct eventpoll *ep, struct epitem *epi, struct epoll_even
 	 * Get current event bits. We can safely use the file* here because
 	 * its usage count has been increased by the caller of this function.
 	 */
-	revents = ep_item_poll(epi, &pt);
+	revents = ep_item_poll(epi, &pt, 1);
 
 	/*
 	 * If the item is "hot" and it is not registered inside the ready
@@ -1674,7 +1654,7 @@ static int ep_send_events_proc(struct eventpoll *ep, struct list_head *head,
 
 		list_del_init(&epi->rdllink);
 
-		revents = ep_item_poll(epi, &pt);
+		revents = ep_item_poll(epi, &pt, 1);
 
 		/*
 		 * If the event mask intersect the caller-requested one,
@@ -2313,11 +2293,10 @@ static int __init eventpoll_init(void)
 	 */
 	ep_nested_calls_init(&poll_loop_ncalls);
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
 	/* Initialize the structure used to perform safe poll wait head wake ups */
 	ep_nested_calls_init(&poll_safewake_ncalls);
-
-	/* Initialize the structure used to perform file's f_op->poll() calls */
-	ep_nested_calls_init(&poll_readywalk_ncalls);
+#endif
 
 	/*
 	 * We can have many thousands of epitems, so prevent this from
@@ -2327,11 +2306,11 @@ static int __init eventpoll_init(void)
 
 	/* Allocates slab cache used to allocate "struct epitem" items */
 	epi_cache = kmem_cache_create("eventpoll_epi", sizeof(struct epitem),
-			0, SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
+			0, SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT, NULL);
 
 	/* Allocates slab cache used to allocate "struct eppoll_entry" */
 	pwq_cache = kmem_cache_create("eventpoll_pwq",
-			sizeof(struct eppoll_entry), 0, SLAB_PANIC, NULL);
+		sizeof(struct eppoll_entry), 0, SLAB_PANIC|SLAB_ACCOUNT, NULL);
 
 	return 0;
 }
diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index 81cecbe6d7cf..b833ffeee1e1 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -291,7 +291,6 @@ static int fat_parse_long(struct inode *dir, loff_t *pos,
 		}
 	}
 parse_long:
-	slots = 0;
 	ds = (struct msdos_dir_slot *)*de;
 	id = ds->id;
 	if (!(id & 0x40))
diff --git a/fs/hfs/bnode.c b/fs/hfs/bnode.c
index 8aec5e732abf..b63a4df7327b 100644
--- a/fs/hfs/bnode.c
+++ b/fs/hfs/bnode.c
@@ -98,13 +98,11 @@ void hfs_bnode_clear(struct hfs_bnode *node, int off, int len)
 void hfs_bnode_copy(struct hfs_bnode *dst_node, int dst,
 		struct hfs_bnode *src_node, int src, int len)
 {
-	struct hfs_btree *tree;
 	struct page *src_page, *dst_page;
 
 	hfs_dbg(BNODE_MOD, "copybytes: %u,%u,%u\n", dst, src, len);
 	if (!len)
 		return;
-	tree = src_node->tree;
 	src += src_node->page_offset;
 	dst += dst_node->page_offset;
 	src_page = src_node->page[0];
@@ -237,7 +235,6 @@ struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *tree, u32 cnid)
 
 static struct hfs_bnode *__hfs_bnode_create(struct hfs_btree *tree, u32 cnid)
 {
-	struct super_block *sb;
 	struct hfs_bnode *node, *node2;
 	struct address_space *mapping;
 	struct page *page;
@@ -249,7 +246,6 @@ static struct hfs_bnode *__hfs_bnode_create(struct hfs_btree *tree, u32 cnid)
 		return NULL;
 	}
 
-	sb = tree->inode->i_sb;
 	size = sizeof(struct hfs_bnode) + tree->pages_per_bnode *
 		sizeof(struct page *);
 	node = kzalloc(size, GFP_KERNEL);
diff --git a/fs/hfsplus/bnode.c b/fs/hfsplus/bnode.c
index d77015c3f22c..177fae4e6581 100644
--- a/fs/hfsplus/bnode.c
+++ b/fs/hfsplus/bnode.c
@@ -127,14 +127,12 @@ void hfs_bnode_clear(struct hfs_bnode *node, int off, int len)
 void hfs_bnode_copy(struct hfs_bnode *dst_node, int dst,
 		    struct hfs_bnode *src_node, int src, int len)
 {
-	struct hfs_btree *tree;
 	struct page **src_page, **dst_page;
 	int l;
 
 	hfs_dbg(BNODE_MOD, "copybytes: %u,%u,%u\n", dst, src, len);
 	if (!len)
 		return;
-	tree = src_node->tree;
 	src += src_node->page_offset;
 	dst += dst_node->page_offset;
 	src_page = src_node->page + (src >> PAGE_SHIFT);
@@ -401,7 +399,6 @@ struct hfs_bnode *hfs_bnode_findhash(struct hfs_btree *tree, u32 cnid)
 
 static struct hfs_bnode *__hfs_bnode_create(struct hfs_btree *tree, u32 cnid)
 {
-	struct super_block *sb;
 	struct hfs_bnode *node, *node2;
 	struct address_space *mapping;
 	struct page *page;
@@ -414,7 +411,6 @@ static struct hfs_bnode *__hfs_bnode_create(struct hfs_btree *tree, u32 cnid)
 		return NULL;
 	}
 
-	sb = tree->inode->i_sb;
 	size = sizeof(struct hfs_bnode) + tree->pages_per_bnode *
 		sizeof(struct page *);
 	node = kzalloc(size, GFP_KERNEL);
diff --git a/fs/nilfs2/namei.c b/fs/nilfs2/namei.c
index 515d13c196da..1a2894aa0194 100644
--- a/fs/nilfs2/namei.c
+++ b/fs/nilfs2/namei.c
@@ -150,7 +150,7 @@ static int nilfs_symlink(struct inode *dir, struct dentry *dentry,
 	if (err)
 		return err;
 
-	inode = nilfs_new_inode(dir, S_IFLNK | S_IRWXUGO);
+	inode = nilfs_new_inode(dir, S_IFLNK | 0777);
 	err = PTR_ERR(inode);
 	if (IS_ERR(inode))
 		goto out;
diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index f65392fecb5c..f572538dcc4f 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -1954,8 +1954,6 @@ static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
 					  err, ii->vfs_inode.i_ino);
 				return err;
 			}
-			mark_buffer_dirty(ibh);
-			nilfs_mdt_mark_dirty(ifile);
 			spin_lock(&nilfs->ns_inode_lock);
 			if (likely(!ii->i_bh))
 				ii->i_bh = ibh;
@@ -1964,6 +1962,10 @@ static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci,
 			goto retry;
 		}
 
+		// Always redirty the buffer to avoid race condition
+		mark_buffer_dirty(ii->i_bh);
+		nilfs_mdt_mark_dirty(ifile);
+
 		clear_bit(NILFS_I_QUEUED, &ii->i_state);
 		set_bit(NILFS_I_BUSY, &ii->i_state);
 		list_move_tail(&ii->i_dirty, &sci->sc_dirty_files);
@@ -2400,11 +2402,11 @@ static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode)
 	return err;
 }
 
-static void nilfs_construction_timeout(unsigned long data)
+static void nilfs_construction_timeout(struct timer_list *t)
 {
-	struct task_struct *p = (struct task_struct *)data;
+	struct nilfs_sc_info *sci = from_timer(sci, t, sc_timer);
 
-	wake_up_process(p);
+	wake_up_process(sci->sc_timer_task);
 }
 
 static void
@@ -2542,8 +2544,7 @@ static int nilfs_segctor_thread(void *arg)
 	struct the_nilfs *nilfs = sci->sc_super->s_fs_info;
 	int timeout = 0;
 
-	sci->sc_timer.data = (unsigned long)current;
-	sci->sc_timer.function = nilfs_construction_timeout;
+	sci->sc_timer_task = current;
 
 	/* start sync. */
 	sci->sc_task = current;
@@ -2674,7 +2675,7 @@ static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb,
 	INIT_LIST_HEAD(&sci->sc_gc_inodes);
 	INIT_LIST_HEAD(&sci->sc_iput_queue);
 	INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func);
-	init_timer(&sci->sc_timer);
+	timer_setup(&sci->sc_timer, nilfs_construction_timeout, 0);
 
 	sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT;
 	sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ;
diff --git a/fs/nilfs2/segment.h b/fs/nilfs2/segment.h
index 1060949d7dd2..84084a4d9b3e 100644
--- a/fs/nilfs2/segment.h
+++ b/fs/nilfs2/segment.h
@@ -180,6 +180,7 @@ struct nilfs_sc_info {
 	unsigned long		sc_watermark;
 
 	struct timer_list	sc_timer;
+	struct task_struct     *sc_timer_task;
 	struct task_struct     *sc_task;
 };
 
diff --git a/fs/nilfs2/sufile.c b/fs/nilfs2/sufile.c
index 1541a1e9221a..1341a41e7b43 100644
--- a/fs/nilfs2/sufile.c
+++ b/fs/nilfs2/sufile.c
@@ -630,22 +630,22 @@ void nilfs_sufile_do_set_error(struct inode *sufile, __u64 segnum,
 }
 
 /**
-  * nilfs_sufile_truncate_range - truncate range of segment array
-  * @sufile: inode of segment usage file
-  * @start: start segment number (inclusive)
-  * @end: end segment number (inclusive)
-  *
-  * Return Value: On success, 0 is returned.  On error, one of the
-  * following negative error codes is returned.
-  *
-  * %-EIO - I/O error.
-  *
-  * %-ENOMEM - Insufficient amount of memory available.
-  *
-  * %-EINVAL - Invalid number of segments specified
-  *
-  * %-EBUSY - Dirty or active segments are present in the range
-  */
+ * nilfs_sufile_truncate_range - truncate range of segment array
+ * @sufile: inode of segment usage file
+ * @start: start segment number (inclusive)
+ * @end: end segment number (inclusive)
+ *
+ * Return Value: On success, 0 is returned.  On error, one of the
+ * following negative error codes is returned.
+ *
+ * %-EIO - I/O error.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ *
+ * %-EINVAL - Invalid number of segments specified
+ *
+ * %-EBUSY - Dirty or active segments are present in the range
+ */
 static int nilfs_sufile_truncate_range(struct inode *sufile,
 				       __u64 start, __u64 end)
 {
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 4fc018dfcfae..3ce20cd44a20 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -160,7 +160,6 @@ struct inode *nilfs_alloc_inode(struct super_block *sb)
 	ii->i_bh = NULL;
 	ii->i_state = 0;
 	ii->i_cno = 0;
-	ii->vfs_inode.i_version = 1;
 	nilfs_mapping_init(&ii->i_btnode_cache, &ii->vfs_inode);
 	return &ii->vfs_inode;
 }
diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index 2dd75bf619ad..afebb5067cec 100644
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -737,7 +737,7 @@ struct nilfs_root *nilfs_lookup_root(struct the_nilfs *nilfs, __u64 cno)
 		} else if (cno > root->cno) {
 			n = n->rb_right;
 		} else {
-			atomic_inc(&root->count);
+			refcount_inc(&root->count);
 			spin_unlock(&nilfs->ns_cptree_lock);
 			return root;
 		}
@@ -776,7 +776,7 @@ nilfs_find_or_create_root(struct the_nilfs *nilfs, __u64 cno)
 		} else if (cno > root->cno) {
 			p = &(*p)->rb_right;
 		} else {
-			atomic_inc(&root->count);
+			refcount_inc(&root->count);
 			spin_unlock(&nilfs->ns_cptree_lock);
 			kfree(new);
 			return root;
@@ -786,7 +786,7 @@ nilfs_find_or_create_root(struct the_nilfs *nilfs, __u64 cno)
 	new->cno = cno;
 	new->ifile = NULL;
 	new->nilfs = nilfs;
-	atomic_set(&new->count, 1);
+	refcount_set(&new->count, 1);
 	atomic64_set(&new->inodes_count, 0);
 	atomic64_set(&new->blocks_count, 0);
 
@@ -806,7 +806,7 @@ nilfs_find_or_create_root(struct the_nilfs *nilfs, __u64 cno)
 
 void nilfs_put_root(struct nilfs_root *root)
 {
-	if (atomic_dec_and_test(&root->count)) {
+	if (refcount_dec_and_test(&root->count)) {
 		struct the_nilfs *nilfs = root->nilfs;
 
 		nilfs_sysfs_delete_snapshot_group(root);
diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h
index b305c6f033e7..883d732b0259 100644
--- a/fs/nilfs2/the_nilfs.h
+++ b/fs/nilfs2/the_nilfs.h
@@ -27,6 +27,7 @@
 #include <linux/blkdev.h>
 #include <linux/backing-dev.h>
 #include <linux/slab.h>
+#include <linux/refcount.h>
 
 struct nilfs_sc_info;
 struct nilfs_sysfs_dev_subgroups;
@@ -246,7 +247,7 @@ struct nilfs_root {
 	__u64 cno;
 	struct rb_node rb_node;
 
-	atomic_t count;
+	refcount_t count;
 	struct the_nilfs *nilfs;
 	struct inode *ifile;
 
@@ -299,7 +300,7 @@ void nilfs_swap_super_block(struct the_nilfs *);
 
 static inline void nilfs_get_root(struct nilfs_root *root)
 {
-	atomic_inc(&root->count);
+	refcount_inc(&root->count);
 }
 
 static inline int nilfs_valid_fs(struct the_nilfs *nilfs)
diff --git a/fs/pipe.c b/fs/pipe.c
index 349c9d56d4b3..6d98566201ef 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -1018,13 +1018,19 @@ const struct file_operations pipefifo_fops = {
 
 /*
  * Currently we rely on the pipe array holding a power-of-2 number
- * of pages.
+ * of pages. Returns 0 on error.
  */
-static inline unsigned int round_pipe_size(unsigned int size)
+unsigned int round_pipe_size(unsigned int size)
 {
 	unsigned long nr_pages;
 
+	if (size < pipe_min_size)
+		size = pipe_min_size;
+
 	nr_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	if (nr_pages == 0)
+		return 0;
+
 	return roundup_pow_of_two(nr_pages) << PAGE_SHIFT;
 }
 
@@ -1040,6 +1046,8 @@ static long pipe_set_size(struct pipe_inode_info *pipe, unsigned long arg)
 	long ret = 0;
 
 	size = round_pipe_size(arg);
+	if (size == 0)
+		return -EINVAL;
 	nr_pages = size >> PAGE_SHIFT;
 
 	if (!nr_pages)
@@ -1117,20 +1125,13 @@ out_revert_acct:
 }
 
 /*
- * This should work even if CONFIG_PROC_FS isn't set, as proc_dointvec_minmax
+ * This should work even if CONFIG_PROC_FS isn't set, as proc_dopipe_max_size
  * will return an error.
  */
 int pipe_proc_fn(struct ctl_table *table, int write, void __user *buf,
 		 size_t *lenp, loff_t *ppos)
 {
-	int ret;
-
-	ret = proc_dointvec_minmax(table, write, buf, lenp, ppos);
-	if (ret < 0 || !write)
-		return ret;
-
-	pipe_max_size = round_pipe_size(pipe_max_size);
-	return ret;
+	return proc_dopipe_max_size(table, write, buf, lenp, ppos);
 }
 
 /*
diff --git a/fs/proc/Makefile b/fs/proc/Makefile
index f7456c4e7d0f..ead487e80510 100644
--- a/fs/proc/Makefile
+++ b/fs/proc/Makefile
@@ -21,6 +21,7 @@ proc-y	+= loadavg.o
 proc-y	+= meminfo.o
 proc-y	+= stat.o
 proc-y	+= uptime.o
+proc-y	+= util.o
 proc-y	+= version.o
 proc-y	+= softirqs.o
 proc-y	+= namespaces.o
diff --git a/fs/proc/array.c b/fs/proc/array.c
index 6f6fc1672ad1..79375fc115d2 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -366,6 +366,11 @@ static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
 		   cpumask_pr_args(&task->cpus_allowed));
 }
 
+static inline void task_core_dumping(struct seq_file *m, struct mm_struct *mm)
+{
+	seq_printf(m, "CoreDumping:\t%d\n", !!mm->core_state);
+}
+
 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
 			struct pid *pid, struct task_struct *task)
 {
@@ -376,6 +381,7 @@ int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
 
 	if (mm) {
 		task_mem(m, mm);
+		task_core_dumping(m, mm);
 		mmput(mm);
 	}
 	task_sig(m, task);
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index a34195e92b20..9aad373cf11d 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -103,28 +103,7 @@ static inline struct task_struct *get_proc_task(struct inode *inode)
 void task_dump_owner(struct task_struct *task, mode_t mode,
 		     kuid_t *ruid, kgid_t *rgid);
 
-static inline unsigned name_to_int(const struct qstr *qstr)
-{
-	const char *name = qstr->name;
-	int len = qstr->len;
-	unsigned n = 0;
-
-	if (len > 1 && *name == '0')
-		goto out;
-	while (len-- > 0) {
-		unsigned c = *name++ - '0';
-		if (c > 9)
-			goto out;
-		if (n >= (~0U-9)/10)
-			goto out;
-		n *= 10;
-		n += c;
-	}
-	return n;
-out:
-	return ~0U;
-}
-
+unsigned name_to_int(const struct qstr *qstr);
 /*
  * Offset of the first process in the /proc root directory..
  */
diff --git a/fs/proc/loadavg.c b/fs/proc/loadavg.c
index 9bc5c58c00ee..a000d7547479 100644
--- a/fs/proc/loadavg.c
+++ b/fs/proc/loadavg.c
@@ -24,7 +24,7 @@ static int loadavg_proc_show(struct seq_file *m, void *v)
 		LOAD_INT(avnrun[1]), LOAD_FRAC(avnrun[1]),
 		LOAD_INT(avnrun[2]), LOAD_FRAC(avnrun[2]),
 		nr_running(), nr_threads,
-		task_active_pid_ns(current)->last_pid);
+		idr_get_cursor(&task_active_pid_ns(current)->idr));
 	return 0;
 }
 
diff --git a/fs/proc/util.c b/fs/proc/util.c
new file mode 100644
index 000000000000..b161cfa0f9fa
--- /dev/null
+++ b/fs/proc/util.c
@@ -0,0 +1,23 @@
+#include <linux/dcache.h>
+
+unsigned name_to_int(const struct qstr *qstr)
+{
+	const char *name = qstr->name;
+	int len = qstr->len;
+	unsigned n = 0;
+
+	if (len > 1 && *name == '0')
+		goto out;
+	do {
+		unsigned c = *name++ - '0';
+		if (c > 9)
+			goto out;
+		if (n >= (~0U-9)/10)
+			goto out;
+		n *= 10;
+		n += c;
+	} while (--len > 0);
+	return n;
+out:
+	return ~0U;
+}