Merge branch 'akpm' (patchbomb from Andrew)

Merge first patchbomb from Andrew Morton:
 - a few minor cifs fixes
 - dma-debug upadtes
 - ocfs2
 - slab
 - about half of MM
 - procfs
 - kernel/exit.c
 - panic.c tweaks
 - printk upates
 - lib/ updates
 - checkpatch updates
 - fs/binfmt updates
 - the drivers/rtc tree
 - nilfs
 - kmod fixes
 - more kernel/exit.c
 - various other misc tweaks and fixes

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (190 commits)
  exit: pidns: fix/update the comments in zap_pid_ns_processes()
  exit: pidns: alloc_pid() leaks pid_namespace if child_reaper is exiting
  exit: exit_notify: re-use "dead" list to autoreap current
  exit: reparent: call forget_original_parent() under tasklist_lock
  exit: reparent: avoid find_new_reaper() if no children
  exit: reparent: introduce find_alive_thread()
  exit: reparent: introduce find_child_reaper()
  exit: reparent: document the ->has_child_subreaper checks
  exit: reparent: s/while_each_thread/for_each_thread/ in find_new_reaper()
  exit: reparent: fix the cross-namespace PR_SET_CHILD_SUBREAPER reparenting
  exit: reparent: fix the dead-parent PR_SET_CHILD_SUBREAPER reparenting
  exit: proc: don't try to flush /proc/tgid/task/tgid
  exit: release_task: fix the comment about group leader accounting
  exit: wait: drop tasklist_lock before psig->c* accounting
  exit: wait: don't use zombie->real_parent
  exit: wait: cleanup the ptrace_reparented() checks
  usermodehelper: kill the kmod_thread_locker logic
  usermodehelper: don't use CLONE_VFORK for ____call_usermodehelper()
  fs/hfs/catalog.c: fix comparison bug in hfs_cat_keycmp
  nilfs2: fix the nilfs_iget() vs. nilfs_new_inode() races
  ...

7 files changed, 205 insertions, 125 deletions

diff --git a/fs/proc/array.c b/fs/proc/array.c
index cd3653e4f35c..bd117d065b82 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -157,20 +157,29 @@ static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
 	struct user_namespace *user_ns = seq_user_ns(m);
 	struct group_info *group_info;
 	int g;
-	struct fdtable *fdt = NULL;
+	struct task_struct *tracer;
 	const struct cred *cred;
-	pid_t ppid, tpid;
+	pid_t ppid, tpid = 0, tgid, ngid;
+	unsigned int max_fds = 0;
 
 	rcu_read_lock();
 	ppid = pid_alive(p) ?
 		task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
-	tpid = 0;
-	if (pid_alive(p)) {
-		struct task_struct *tracer = ptrace_parent(p);
-		if (tracer)
-			tpid = task_pid_nr_ns(tracer, ns);
-	}
+
+	tracer = ptrace_parent(p);
+	if (tracer)
+		tpid = task_pid_nr_ns(tracer, ns);
+
+	tgid = task_tgid_nr_ns(p, ns);
+	ngid = task_numa_group_id(p);
 	cred = get_task_cred(p);
+
+	task_lock(p);
+	if (p->files)
+		max_fds = files_fdtable(p->files)->max_fds;
+	task_unlock(p);
+	rcu_read_unlock();
+
 	seq_printf(m,
 		"State:\t%s\n"
 		"Tgid:\t%d\n"
@@ -179,12 +188,10 @@ static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
 		"PPid:\t%d\n"
 		"TracerPid:\t%d\n"
 		"Uid:\t%d\t%d\t%d\t%d\n"
-		"Gid:\t%d\t%d\t%d\t%d\n",
+		"Gid:\t%d\t%d\t%d\t%d\n"
+		"FDSize:\t%d\nGroups:\t",
 		get_task_state(p),
-		task_tgid_nr_ns(p, ns),
-		task_numa_group_id(p),
-		pid_nr_ns(pid, ns),
-		ppid, tpid,
+		tgid, ngid, pid_nr_ns(pid, ns), ppid, tpid,
 		from_kuid_munged(user_ns, cred->uid),
 		from_kuid_munged(user_ns, cred->euid),
 		from_kuid_munged(user_ns, cred->suid),
@@ -192,20 +199,10 @@ static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
 		from_kgid_munged(user_ns, cred->gid),
 		from_kgid_munged(user_ns, cred->egid),
 		from_kgid_munged(user_ns, cred->sgid),
-		from_kgid_munged(user_ns, cred->fsgid));
-
-	task_lock(p);
-	if (p->files)
-		fdt = files_fdtable(p->files);
-	seq_printf(m,
-		"FDSize:\t%d\n"
-		"Groups:\t",
-		fdt ? fdt->max_fds : 0);
-	rcu_read_unlock();
+		from_kgid_munged(user_ns, cred->fsgid),
+		max_fds);
 
 	group_info = cred->group_info;
-	task_unlock(p);
-
 	for (g = 0; g < group_info->ngroups; g++)
 		seq_printf(m, "%d ",
 			   from_kgid_munged(user_ns, GROUP_AT(group_info, g)));
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 64891f3e41bd..590aeda5af12 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2618,6 +2618,9 @@ static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
 		dput(dentry);
 	}
 
+	if (pid == tgid)
+		return;
+
 	name.name = buf;
 	name.len = snprintf(buf, sizeof(buf), "%d", tgid);
 	leader = d_hash_and_lookup(mnt->mnt_root, &name);
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 317b72641ebf..7fea13229f33 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -31,9 +31,73 @@ static DEFINE_SPINLOCK(proc_subdir_lock);
 
 static int proc_match(unsigned int len, const char *name, struct proc_dir_entry *de)
 {
-	if (de->namelen != len)
-		return 0;
-	return !memcmp(name, de->name, len);
+	if (len < de->namelen)
+		return -1;
+	if (len > de->namelen)
+		return 1;
+
+	return memcmp(name, de->name, len);
+}
+
+static struct proc_dir_entry *pde_subdir_first(struct proc_dir_entry *dir)
+{
+	return rb_entry_safe(rb_first(&dir->subdir), struct proc_dir_entry,
+			     subdir_node);
+}
+
+static struct proc_dir_entry *pde_subdir_next(struct proc_dir_entry *dir)
+{
+	return rb_entry_safe(rb_next(&dir->subdir_node), struct proc_dir_entry,
+			     subdir_node);
+}
+
+static struct proc_dir_entry *pde_subdir_find(struct proc_dir_entry *dir,
+					      const char *name,
+					      unsigned int len)
+{
+	struct rb_node *node = dir->subdir.rb_node;
+
+	while (node) {
+		struct proc_dir_entry *de = container_of(node,
+							 struct proc_dir_entry,
+							 subdir_node);
+		int result = proc_match(len, name, de);
+
+		if (result < 0)
+			node = node->rb_left;
+		else if (result > 0)
+			node = node->rb_right;
+		else
+			return de;
+	}
+	return NULL;
+}
+
+static bool pde_subdir_insert(struct proc_dir_entry *dir,
+			      struct proc_dir_entry *de)
+{
+	struct rb_root *root = &dir->subdir;
+	struct rb_node **new = &root->rb_node, *parent = NULL;
+
+	/* Figure out where to put new node */
+	while (*new) {
+		struct proc_dir_entry *this =
+			container_of(*new, struct proc_dir_entry, subdir_node);
+		int result = proc_match(de->namelen, de->name, this);
+
+		parent = *new;
+		if (result < 0)
+			new = &(*new)->rb_left;
+		else if (result > 0)
+			new = &(*new)->rb_right;
+		else
+			return false;
+	}
+
+	/* Add new node and rebalance tree. */
+	rb_link_node(&de->subdir_node, parent, new);
+	rb_insert_color(&de->subdir_node, root);
+	return true;
 }
 
 static int proc_notify_change(struct dentry *dentry, struct iattr *iattr)
@@ -92,10 +156,7 @@ static int __xlate_proc_name(const char *name, struct proc_dir_entry **ret,
 			break;
 
 		len = next - cp;
-		for (de = de->subdir; de ; de = de->next) {
-			if (proc_match(len, cp, de))
-				break;
-		}
+		de = pde_subdir_find(de, cp, len);
 		if (!de) {
 			WARN(1, "name '%s'\n", name);
 			return -ENOENT;
@@ -183,19 +244,16 @@ struct dentry *proc_lookup_de(struct proc_dir_entry *de, struct inode *dir,
 	struct inode *inode;
 
 	spin_lock(&proc_subdir_lock);
-	for (de = de->subdir; de ; de = de->next) {
-		if (de->namelen != dentry->d_name.len)
-			continue;
-		if (!memcmp(dentry->d_name.name, de->name, de->namelen)) {
-			pde_get(de);
-			spin_unlock(&proc_subdir_lock);
-			inode = proc_get_inode(dir->i_sb, de);
-			if (!inode)
-				return ERR_PTR(-ENOMEM);
-			d_set_d_op(dentry, &simple_dentry_operations);
-			d_add(dentry, inode);
-			return NULL;
-		}
+	de = pde_subdir_find(de, dentry->d_name.name, dentry->d_name.len);
+	if (de) {
+		pde_get(de);
+		spin_unlock(&proc_subdir_lock);
+		inode = proc_get_inode(dir->i_sb, de);
+		if (!inode)
+			return ERR_PTR(-ENOMEM);
+		d_set_d_op(dentry, &simple_dentry_operations);
+		d_add(dentry, inode);
+		return NULL;
 	}
 	spin_unlock(&proc_subdir_lock);
 	return ERR_PTR(-ENOENT);
@@ -225,7 +283,7 @@ int proc_readdir_de(struct proc_dir_entry *de, struct file *file,
 		return 0;
 
 	spin_lock(&proc_subdir_lock);
-	de = de->subdir;
+	de = pde_subdir_first(de);
 	i = ctx->pos - 2;
 	for (;;) {
 		if (!de) {
@@ -234,7 +292,7 @@ int proc_readdir_de(struct proc_dir_entry *de, struct file *file,
 		}
 		if (!i)
 			break;
-		de = de->next;
+		de = pde_subdir_next(de);
 		i--;
 	}
 
@@ -249,7 +307,7 @@ int proc_readdir_de(struct proc_dir_entry *de, struct file *file,
 		}
 		spin_lock(&proc_subdir_lock);
 		ctx->pos++;
-		next = de->next;
+		next = pde_subdir_next(de);
 		pde_put(de);
 		de = next;
 	} while (de);
@@ -286,9 +344,8 @@ static const struct inode_operations proc_dir_inode_operations = {
 
 static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp)
 {
-	struct proc_dir_entry *tmp;
 	int ret;
-	
+
 	ret = proc_alloc_inum(&dp->low_ino);
 	if (ret)
 		return ret;
@@ -304,21 +361,21 @@ static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp
 		dp->proc_iops = &proc_file_inode_operations;
 	} else {
 		WARN_ON(1);
+		proc_free_inum(dp->low_ino);
 		return -EINVAL;
 	}
 
 	spin_lock(&proc_subdir_lock);
-
-	for (tmp = dir->subdir; tmp; tmp = tmp->next)
-		if (strcmp(tmp->name, dp->name) == 0) {
-			WARN(1, "proc_dir_entry '%s/%s' already registered\n",
-				dir->name, dp->name);
-			break;
-		}
-
-	dp->next = dir->subdir;
 	dp->parent = dir;
-	dir->subdir = dp;
+	if (pde_subdir_insert(dir, dp) == false) {
+		WARN(1, "proc_dir_entry '%s/%s' already registered\n",
+		     dir->name, dp->name);
+		spin_unlock(&proc_subdir_lock);
+		if (S_ISDIR(dp->mode))
+			dir->nlink--;
+		proc_free_inum(dp->low_ino);
+		return -EEXIST;
+	}
 	spin_unlock(&proc_subdir_lock);
 
 	return 0;
@@ -354,6 +411,7 @@ static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent,
 	ent->namelen = qstr.len;
 	ent->mode = mode;
 	ent->nlink = nlink;
+	ent->subdir = RB_ROOT;
 	atomic_set(&ent->count, 1);
 	spin_lock_init(&ent->pde_unload_lock);
 	INIT_LIST_HEAD(&ent->pde_openers);
@@ -485,7 +543,6 @@ void pde_put(struct proc_dir_entry *pde)
  */
 void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
 {
-	struct proc_dir_entry **p;
 	struct proc_dir_entry *de = NULL;
 	const char *fn = name;
 	unsigned int len;
@@ -497,14 +554,9 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
 	}
 	len = strlen(fn);
 
-	for (p = &parent->subdir; *p; p=&(*p)->next ) {
-		if (proc_match(len, fn, *p)) {
-			de = *p;
-			*p = de->next;
-			de->next = NULL;
-			break;
-		}
-	}
+	de = pde_subdir_find(parent, fn, len);
+	if (de)
+		rb_erase(&de->subdir_node, &parent->subdir);
 	spin_unlock(&proc_subdir_lock);
 	if (!de) {
 		WARN(1, "name '%s'\n", name);
@@ -516,16 +568,15 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
 	if (S_ISDIR(de->mode))
 		parent->nlink--;
 	de->nlink = 0;
-	WARN(de->subdir, "%s: removing non-empty directory "
-			 "'%s/%s', leaking at least '%s'\n", __func__,
-			 de->parent->name, de->name, de->subdir->name);
+	WARN(pde_subdir_first(de),
+	     "%s: removing non-empty directory '%s/%s', leaking at least '%s'\n",
+	     __func__, de->parent->name, de->name, pde_subdir_first(de)->name);
 	pde_put(de);
 }
 EXPORT_SYMBOL(remove_proc_entry);
 
 int remove_proc_subtree(const char *name, struct proc_dir_entry *parent)
 {
-	struct proc_dir_entry **p;
 	struct proc_dir_entry *root = NULL, *de, *next;
 	const char *fn = name;
 	unsigned int len;
@@ -537,24 +588,18 @@ int remove_proc_subtree(const char *name, struct proc_dir_entry *parent)
 	}
 	len = strlen(fn);
 
-	for (p = &parent->subdir; *p; p=&(*p)->next ) {
-		if (proc_match(len, fn, *p)) {
-			root = *p;
-			*p = root->next;
-			root->next = NULL;
-			break;
-		}
-	}
+	root = pde_subdir_find(parent, fn, len);
 	if (!root) {
 		spin_unlock(&proc_subdir_lock);
 		return -ENOENT;
 	}
+	rb_erase(&root->subdir_node, &parent->subdir);
+
 	de = root;
 	while (1) {
-		next = de->subdir;
+		next = pde_subdir_first(de);
 		if (next) {
-			de->subdir = next->next;
-			next->next = NULL;
+			rb_erase(&next->subdir_node, &de->subdir);
 			de = next;
 			continue;
 		}
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index aa7a0ee182e1..7fb1a4869fd0 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -24,10 +24,9 @@ struct mempolicy;
  * tree) of these proc_dir_entries, so that we can dynamically
  * add new files to /proc.
  *
- * The "next" pointer creates a linked list of one /proc directory,
- * while parent/subdir create the directory structure (every
- * /proc file has a parent, but "subdir" is NULL for all
- * non-directory entries).
+ * parent/subdir are used for the directory structure (every /proc file has a
+ * parent, but "subdir" is empty for all non-directory entries).
+ * subdir_node is used to build the rb tree "subdir" of the parent.
  */
 struct proc_dir_entry {
 	unsigned int low_ino;
@@ -38,7 +37,9 @@ struct proc_dir_entry {
 	loff_t size;
 	const struct inode_operations *proc_iops;
 	const struct file_operations *proc_fops;
-	struct proc_dir_entry *next, *parent, *subdir;
+	struct proc_dir_entry *parent;
+	struct rb_root subdir;
+	struct rb_node subdir_node;
 	void *data;
 	atomic_t count;		/* use count */
 	atomic_t in_use;	/* number of callers into module in progress; */
diff --git a/fs/proc/proc_net.c b/fs/proc/proc_net.c
index a63af3e0a612..1bde894bc624 100644
--- a/fs/proc/proc_net.c
+++ b/fs/proc/proc_net.c
@@ -192,6 +192,7 @@ static __net_init int proc_net_ns_init(struct net *net)
 	if (!netd)
 		goto out;
 
+	netd->subdir = RB_ROOT;
 	netd->data = net;
 	netd->nlink = 2;
 	netd->namelen = 3;
diff --git a/fs/proc/root.c b/fs/proc/root.c
index 094e44d4a6be..e74ac9f1a2c0 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -251,6 +251,7 @@ struct proc_dir_entry proc_root = {
 	.proc_iops	= &proc_root_inode_operations, 
 	.proc_fops	= &proc_root_operations,
 	.parent		= &proc_root,
+	.subdir		= RB_ROOT,
 	.name		= "/proc",
 };
 
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index f6734c6b66a6..246eae84b13b 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -447,58 +447,91 @@ struct mem_size_stats {
 	u64 pss;
 };
 
+static void smaps_account(struct mem_size_stats *mss, struct page *page,
+		unsigned long size, bool young, bool dirty)
+{
+	int mapcount;
+
+	if (PageAnon(page))
+		mss->anonymous += size;
 
-static void smaps_pte_entry(pte_t ptent, unsigned long addr,
-		unsigned long ptent_size, struct mm_walk *walk)
+	mss->resident += size;
+	/* Accumulate the size in pages that have been accessed. */
+	if (young || PageReferenced(page))
+		mss->referenced += size;
+	mapcount = page_mapcount(page);
+	if (mapcount >= 2) {
+		u64 pss_delta;
+
+		if (dirty || PageDirty(page))
+			mss->shared_dirty += size;
+		else
+			mss->shared_clean += size;
+		pss_delta = (u64)size << PSS_SHIFT;
+		do_div(pss_delta, mapcount);
+		mss->pss += pss_delta;
+	} else {
+		if (dirty || PageDirty(page))
+			mss->private_dirty += size;
+		else
+			mss->private_clean += size;
+		mss->pss += (u64)size << PSS_SHIFT;
+	}
+}
+
+static void smaps_pte_entry(pte_t *pte, unsigned long addr,
+		struct mm_walk *walk)
 {
 	struct mem_size_stats *mss = walk->private;
 	struct vm_area_struct *vma = mss->vma;
 	pgoff_t pgoff = linear_page_index(vma, addr);
 	struct page *page = NULL;
-	int mapcount;
 
-	if (pte_present(ptent)) {
-		page = vm_normal_page(vma, addr, ptent);
-	} else if (is_swap_pte(ptent)) {
-		swp_entry_t swpent = pte_to_swp_entry(ptent);
+	if (pte_present(*pte)) {
+		page = vm_normal_page(vma, addr, *pte);
+	} else if (is_swap_pte(*pte)) {
+		swp_entry_t swpent = pte_to_swp_entry(*pte);
 
 		if (!non_swap_entry(swpent))
-			mss->swap += ptent_size;
+			mss->swap += PAGE_SIZE;
 		else if (is_migration_entry(swpent))
 			page = migration_entry_to_page(swpent);
-	} else if (pte_file(ptent)) {
-		if (pte_to_pgoff(ptent) != pgoff)
-			mss->nonlinear += ptent_size;
+	} else if (pte_file(*pte)) {
+		if (pte_to_pgoff(*pte) != pgoff)
+			mss->nonlinear += PAGE_SIZE;
 	}
 
 	if (!page)
 		return;
 
-	if (PageAnon(page))
-		mss->anonymous += ptent_size;
-
 	if (page->index != pgoff)
-		mss->nonlinear += ptent_size;
+		mss->nonlinear += PAGE_SIZE;
 
-	mss->resident += ptent_size;
-	/* Accumulate the size in pages that have been accessed. */
-	if (pte_young(ptent) || PageReferenced(page))
-		mss->referenced += ptent_size;
-	mapcount = page_mapcount(page);
-	if (mapcount >= 2) {
-		if (pte_dirty(ptent) || PageDirty(page))
-			mss->shared_dirty += ptent_size;
-		else
-			mss->shared_clean += ptent_size;
-		mss->pss += (ptent_size << PSS_SHIFT) / mapcount;
-	} else {
-		if (pte_dirty(ptent) || PageDirty(page))
-			mss->private_dirty += ptent_size;
-		else
-			mss->private_clean += ptent_size;
-		mss->pss += (ptent_size << PSS_SHIFT);
-	}
+	smaps_account(mss, page, PAGE_SIZE, pte_young(*pte), pte_dirty(*pte));
+}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
+		struct mm_walk *walk)
+{
+	struct mem_size_stats *mss = walk->private;
+	struct vm_area_struct *vma = mss->vma;
+	struct page *page;
+
+	/* FOLL_DUMP will return -EFAULT on huge zero page */
+	page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
+	if (IS_ERR_OR_NULL(page))
+		return;
+	mss->anonymous_thp += HPAGE_PMD_SIZE;
+	smaps_account(mss, page, HPAGE_PMD_SIZE,
+			pmd_young(*pmd), pmd_dirty(*pmd));
 }
+#else
+static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
+		struct mm_walk *walk)
+{
+}
+#endif
 
 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 			   struct mm_walk *walk)
@@ -509,9 +542,8 @@ static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 	spinlock_t *ptl;
 
 	if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
-		smaps_pte_entry(*(pte_t *)pmd, addr, HPAGE_PMD_SIZE, walk);
+		smaps_pmd_entry(pmd, addr, walk);
 		spin_unlock(ptl);
-		mss->anonymous_thp += HPAGE_PMD_SIZE;
 		return 0;
 	}
 
@@ -524,7 +556,7 @@ static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 	 */
 	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
 	for (; addr != end; pte++, addr += PAGE_SIZE)
-		smaps_pte_entry(*pte, addr, PAGE_SIZE, walk);
+		smaps_pte_entry(pte, addr, walk);
 	pte_unmap_unlock(pte - 1, ptl);
 	cond_resched();
 	return 0;