Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull VFS updates from Al Viro,

Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).

7kloc removed.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
  don't bother with deferred freeing of fdtables
  proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
  proc: Make the PROC_I() and PDE() macros internal to procfs
  proc: Supply a function to remove a proc entry by PDE
  take cgroup_open() and cpuset_open() to fs/proc/base.c
  ppc: Clean up scanlog
  ppc: Clean up rtas_flash driver somewhat
  hostap: proc: Use remove_proc_subtree()
  drm: proc: Use remove_proc_subtree()
  drm: proc: Use minor->index to label things, not PDE->name
  drm: Constify drm_proc_list[]
  zoran: Don't print proc_dir_entry data in debug
  reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
  proc: Supply an accessor for getting the data from a PDE's parent
  airo: Use remove_proc_subtree()
  rtl8192u: Don't need to save device proc dir PDE
  rtl8187se: Use a dir under /proc/net/r8180/
  proc: Add proc_mkdir_data()
  proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
  proc: Move PDE_NET() to fs/proc/proc_net.c
  ...

12 files changed, 501 insertions, 612 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 3861bcec41f..dd51e50001f 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -405,6 +405,37 @@ static const struct file_operations proc_lstats_operations = {
 
 #endif
 
+#ifdef CONFIG_CGROUPS
+static int cgroup_open(struct inode *inode, struct file *file)
+{
+	struct pid *pid = PROC_I(inode)->pid;
+	return single_open(file, proc_cgroup_show, pid);
+}
+
+static const struct file_operations proc_cgroup_operations = {
+	.open		= cgroup_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+#endif
+
+#ifdef CONFIG_PROC_PID_CPUSET
+
+static int cpuset_open(struct inode *inode, struct file *file)
+{
+	struct pid *pid = PROC_I(inode)->pid;
+	return single_open(file, proc_cpuset_show, pid);
+}
+
+static const struct file_operations proc_cpuset_operations = {
+	.open		= cpuset_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+#endif
+
 static int proc_oom_score(struct task_struct *task, char *buffer)
 {
 	unsigned long totalpages = totalram_pages + total_swap_pages;
@@ -1621,6 +1652,15 @@ int pid_revalidate(struct dentry *dentry, unsigned int flags)
 	return 0;
 }
 
+int pid_delete_dentry(const struct dentry *dentry)
+{
+	/* Is the task we represent dead?
+	 * If so, then don't put the dentry on the lru list,
+	 * kill it immediately.
+	 */
+	return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
+}
+
 const struct dentry_operations pid_dentry_operations =
 {
 	.d_revalidate	= pid_revalidate,
@@ -2893,7 +2933,7 @@ retry:
 	return iter;
 }
 
-#define TGID_OFFSET (FIRST_PROCESS_ENTRY)
+#define TGID_OFFSET (FIRST_PROCESS_ENTRY + 1)
 
 static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
 	struct tgid_iter iter)
@@ -2916,13 +2956,21 @@ int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
 	struct tgid_iter iter;
 	struct pid_namespace *ns;
 	filldir_t __filldir;
+	loff_t pos = filp->f_pos;
 
-	if (filp->f_pos >= PID_MAX_LIMIT + TGID_OFFSET)
+	if (pos >= PID_MAX_LIMIT + TGID_OFFSET)
 		goto out;
 
-	ns = filp->f_dentry->d_sb->s_fs_info;
+	if (pos == TGID_OFFSET - 1) {
+		if (proc_fill_cache(filp, dirent, filldir, "self", 4,
+					NULL, NULL, NULL) < 0)
+			goto out;
+		iter.tgid = 0;
+	} else {
+		iter.tgid = pos - TGID_OFFSET;
+	}
 	iter.task = NULL;
-	iter.tgid = filp->f_pos - TGID_OFFSET;
+	ns = filp->f_dentry->d_sb->s_fs_info;
 	for (iter = next_tgid(ns, iter);
 	     iter.task;
 	     iter.tgid += 1, iter = next_tgid(ns, iter)) {
diff --git a/fs/proc/fd.h b/fs/proc/fd.h
index cbb1d47deda..7c047f256ae 100644
--- a/fs/proc/fd.h
+++ b/fs/proc/fd.h
@@ -11,4 +11,9 @@ extern const struct inode_operations proc_fdinfo_inode_operations;
 
 extern int proc_fd_permission(struct inode *inode, int mask);
 
+static inline int proc_fd(struct inode *inode)
+{
+	return PROC_I(inode)->fd;
+}
+
 #endif /* __PROCFS_FD_H__ */
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 21e1a8f1659..a2596afffae 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -36,212 +36,6 @@ static int proc_match(unsigned int len, const char *name, struct proc_dir_entry
 	return !memcmp(name, de->name, len);
 }
 
-/* buffer size is one page but our output routines use some slack for overruns */
-#define PROC_BLOCK_SIZE	(PAGE_SIZE - 1024)
-
-static ssize_t
-__proc_file_read(struct file *file, char __user *buf, size_t nbytes,
-	       loff_t *ppos)
-{
-	struct inode * inode = file_inode(file);
-	char 	*page;
-	ssize_t	retval=0;
-	int	eof=0;
-	ssize_t	n, count;
-	char	*start;
-	struct proc_dir_entry * dp;
-	unsigned long long pos;
-
-	/*
-	 * Gaah, please just use "seq_file" instead. The legacy /proc
-	 * interfaces cut loff_t down to off_t for reads, and ignore
-	 * the offset entirely for writes..
-	 */
-	pos = *ppos;
-	if (pos > MAX_NON_LFS)
-		return 0;
-	if (nbytes > MAX_NON_LFS - pos)
-		nbytes = MAX_NON_LFS - pos;
-
-	dp = PDE(inode);
-	if (!(page = (char*) __get_free_page(GFP_TEMPORARY)))
-		return -ENOMEM;
-
-	while ((nbytes > 0) && !eof) {
-		count = min_t(size_t, PROC_BLOCK_SIZE, nbytes);
-
-		start = NULL;
-		if (dp->read_proc) {
-			/*
-			 * How to be a proc read function
-			 * ------------------------------
-			 * Prototype:
-			 *    int f(char *buffer, char **start, off_t offset,
-			 *          int count, int *peof, void *dat)
-			 *
-			 * Assume that the buffer is "count" bytes in size.
-			 *
-			 * If you know you have supplied all the data you
-			 * have, set *peof.
-			 *
-			 * You have three ways to return data:
-			 * 0) Leave *start = NULL.  (This is the default.)
-			 *    Put the data of the requested offset at that
-			 *    offset within the buffer.  Return the number (n)
-			 *    of bytes there are from the beginning of the
-			 *    buffer up to the last byte of data.  If the
-			 *    number of supplied bytes (= n - offset) is 
-			 *    greater than zero and you didn't signal eof
-			 *    and the reader is prepared to take more data
-			 *    you will be called again with the requested
-			 *    offset advanced by the number of bytes 
-			 *    absorbed.  This interface is useful for files
-			 *    no larger than the buffer.
-			 * 1) Set *start = an unsigned long value less than
-			 *    the buffer address but greater than zero.
-			 *    Put the data of the requested offset at the
-			 *    beginning of the buffer.  Return the number of
-			 *    bytes of data placed there.  If this number is
-			 *    greater than zero and you didn't signal eof
-			 *    and the reader is prepared to take more data
-			 *    you will be called again with the requested
-			 *    offset advanced by *start.  This interface is
-			 *    useful when you have a large file consisting
-			 *    of a series of blocks which you want to count
-			 *    and return as wholes.
-			 *    (Hack by Paul.Russell@rustcorp.com.au)
-			 * 2) Set *start = an address within the buffer.
-			 *    Put the data of the requested offset at *start.
-			 *    Return the number of bytes of data placed there.
-			 *    If this number is greater than zero and you
-			 *    didn't signal eof and the reader is prepared to
-			 *    take more data you will be called again with the
-			 *    requested offset advanced by the number of bytes
-			 *    absorbed.
-			 */
-			n = dp->read_proc(page, &start, *ppos,
-					  count, &eof, dp->data);
-		} else
-			break;
-
-		if (n == 0)   /* end of file */
-			break;
-		if (n < 0) {  /* error */
-			if (retval == 0)
-				retval = n;
-			break;
-		}
-
-		if (start == NULL) {
-			if (n > PAGE_SIZE)	/* Apparent buffer overflow */
-				n = PAGE_SIZE;
-			n -= *ppos;
-			if (n <= 0)
-				break;
-			if (n > count)
-				n = count;
-			start = page + *ppos;
-		} else if (start < page) {
-			if (n > PAGE_SIZE)	/* Apparent buffer overflow */
-				n = PAGE_SIZE;
-			if (n > count) {
-				/*
-				 * Don't reduce n because doing so might
-				 * cut off part of a data block.
-				 */
-				pr_warn("proc_file_read: count exceeded\n");
-			}
-		} else /* start >= page */ {
-			unsigned long startoff = (unsigned long)(start - page);
-			if (n > (PAGE_SIZE - startoff))	/* buffer overflow? */
-				n = PAGE_SIZE - startoff;
-			if (n > count)
-				n = count;
-		}
-		
- 		n -= copy_to_user(buf, start < page ? page : start, n);
-		if (n == 0) {
-			if (retval == 0)
-				retval = -EFAULT;
-			break;
-		}
-
-		*ppos += start < page ? (unsigned long)start : n;
-		nbytes -= n;
-		buf += n;
-		retval += n;
-	}
-	free_page((unsigned long) page);
-	return retval;
-}
-
-static ssize_t
-proc_file_read(struct file *file, char __user *buf, size_t nbytes,
-	       loff_t *ppos)
-{
-	struct proc_dir_entry *pde = PDE(file_inode(file));
-	ssize_t rv = -EIO;
-
-	spin_lock(&pde->pde_unload_lock);
-	if (!pde->proc_fops) {
-		spin_unlock(&pde->pde_unload_lock);
-		return rv;
-	}
-	pde->pde_users++;
-	spin_unlock(&pde->pde_unload_lock);
-
-	rv = __proc_file_read(file, buf, nbytes, ppos);
-
-	pde_users_dec(pde);
-	return rv;
-}
-
-static ssize_t
-proc_file_write(struct file *file, const char __user *buffer,
-		size_t count, loff_t *ppos)
-{
-	struct proc_dir_entry *pde = PDE(file_inode(file));
-	ssize_t rv = -EIO;
-
-	if (pde->write_proc) {
-		spin_lock(&pde->pde_unload_lock);
-		if (!pde->proc_fops) {
-			spin_unlock(&pde->pde_unload_lock);
-			return rv;
-		}
-		pde->pde_users++;
-		spin_unlock(&pde->pde_unload_lock);
-
-		/* FIXME: does this routine need ppos?  probably... */
-		rv = pde->write_proc(file, buffer, count, pde->data);
-		pde_users_dec(pde);
-	}
-	return rv;
-}
-
-
-static loff_t
-proc_file_lseek(struct file *file, loff_t offset, int orig)
-{
-	loff_t retval = -EINVAL;
-	switch (orig) {
-	case 1:
-		offset += file->f_pos;
-	/* fallthrough */
-	case 0:
-		if (offset < 0 || offset > MAX_NON_LFS)
-			break;
-		file->f_pos = retval = offset;
-	}
-	return retval;
-}
-
-static const struct file_operations proc_file_operations = {
-	.llseek		= proc_file_lseek,
-	.read		= proc_file_read,
-	.write		= proc_file_write,
-};
-
 static int proc_notify_change(struct dentry *dentry, struct iattr *iattr)
 {
 	struct inode *inode = dentry->d_inode;
@@ -371,7 +165,7 @@ void proc_free_inum(unsigned int inum)
 
 static void *proc_follow_link(struct dentry *dentry, struct nameidata *nd)
 {
-	nd_set_link(nd, PDE(dentry->d_inode)->data);
+	nd_set_link(nd, __PDE_DATA(dentry->d_inode));
 	return NULL;
 }
 
@@ -541,19 +335,17 @@ static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp
 		return ret;
 
 	if (S_ISDIR(dp->mode)) {
-		if (dp->proc_iops == NULL) {
-			dp->proc_fops = &proc_dir_operations;
-			dp->proc_iops = &proc_dir_inode_operations;
-		}
+		dp->proc_fops = &proc_dir_operations;
+		dp->proc_iops = &proc_dir_inode_operations;
 		dir->nlink++;
 	} else if (S_ISLNK(dp->mode)) {
-		if (dp->proc_iops == NULL)
-			dp->proc_iops = &proc_link_inode_operations;
+		dp->proc_iops = &proc_link_inode_operations;
 	} else if (S_ISREG(dp->mode)) {
-		if (dp->proc_fops == NULL)
-			dp->proc_fops = &proc_file_operations;
-		if (dp->proc_iops == NULL)
-			dp->proc_iops = &proc_file_inode_operations;
+		BUG_ON(dp->proc_fops == NULL);
+		dp->proc_iops = &proc_file_inode_operations;
+	} else {
+		WARN_ON(1);
+		return -EINVAL;
 	}
 
 	spin_lock(&proc_subdir_lock);
@@ -636,13 +428,17 @@ struct proc_dir_entry *proc_symlink(const char *name,
 }
 EXPORT_SYMBOL(proc_symlink);
 
-struct proc_dir_entry *proc_mkdir_mode(const char *name, umode_t mode,
-		struct proc_dir_entry *parent)
+struct proc_dir_entry *proc_mkdir_data(const char *name, umode_t mode,
+		struct proc_dir_entry *parent, void *data)
 {
 	struct proc_dir_entry *ent;
 
+	if (mode == 0)
+		mode = S_IRUGO | S_IXUGO;
+
 	ent = __proc_create(&parent, name, S_IFDIR | mode, 2);
 	if (ent) {
+		ent->data = data;
 		if (proc_register(parent, ent) < 0) {
 			kfree(ent);
 			ent = NULL;
@@ -650,82 +446,39 @@ struct proc_dir_entry *proc_mkdir_mode(const char *name, umode_t mode,
 	}
 	return ent;
 }
-EXPORT_SYMBOL(proc_mkdir_mode);
+EXPORT_SYMBOL_GPL(proc_mkdir_data);
 
-struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name,
-		struct proc_dir_entry *parent)
+struct proc_dir_entry *proc_mkdir_mode(const char *name, umode_t mode,
+				       struct proc_dir_entry *parent)
 {
-	struct proc_dir_entry *ent;
-
-	ent = __proc_create(&parent, name, S_IFDIR | S_IRUGO | S_IXUGO, 2);
-	if (ent) {
-		ent->data = net;
-		if (proc_register(parent, ent) < 0) {
-			kfree(ent);
-			ent = NULL;
-		}
-	}
-	return ent;
+	return proc_mkdir_data(name, mode, parent, NULL);
 }
-EXPORT_SYMBOL_GPL(proc_net_mkdir);
+EXPORT_SYMBOL(proc_mkdir_mode);
 
 struct proc_dir_entry *proc_mkdir(const char *name,
 		struct proc_dir_entry *parent)
 {
-	return proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent);
+	return proc_mkdir_data(name, 0, parent, NULL);
 }
 EXPORT_SYMBOL(proc_mkdir);
 
-struct proc_dir_entry *create_proc_entry(const char *name, umode_t mode,
-					 struct proc_dir_entry *parent)
-{
-	struct proc_dir_entry *ent;
-	nlink_t nlink;
-
-	if (S_ISDIR(mode)) {
-		if ((mode & S_IALLUGO) == 0)
-			mode |= S_IRUGO | S_IXUGO;
-		nlink = 2;
-	} else {
-		if ((mode & S_IFMT) == 0)
-			mode |= S_IFREG;
-		if ((mode & S_IALLUGO) == 0)
-			mode |= S_IRUGO;
-		nlink = 1;
-	}
-
-	ent = __proc_create(&parent, name, mode, nlink);
-	if (ent) {
-		if (proc_register(parent, ent) < 0) {
-			kfree(ent);
-			ent = NULL;
-		}
-	}
-	return ent;
-}
-EXPORT_SYMBOL(create_proc_entry);
-
 struct proc_dir_entry *proc_create_data(const char *name, umode_t mode,
 					struct proc_dir_entry *parent,
 					const struct file_operations *proc_fops,
 					void *data)
 {
 	struct proc_dir_entry *pde;
-	nlink_t nlink;
+	if ((mode & S_IFMT) == 0)
+		mode |= S_IFREG;
 
-	if (S_ISDIR(mode)) {
-		if ((mode & S_IALLUGO) == 0)
-			mode |= S_IRUGO | S_IXUGO;
-		nlink = 2;
-	} else {
-		if ((mode & S_IFMT) == 0)
-			mode |= S_IFREG;
-		if ((mode & S_IALLUGO) == 0)
-			mode |= S_IRUGO;
-		nlink = 1;
+	if (!S_ISREG(mode)) {
+		WARN_ON(1);	/* use proc_mkdir() */
+		return NULL;
 	}
 
-	pde = __proc_create(&parent, name, mode, nlink);
+	if ((mode & S_IALLUGO) == 0)
+		mode |= S_IRUGO;
+	pde = __proc_create(&parent, name, mode, 1);
 	if (!pde)
 		goto out;
 	pde->proc_fops = proc_fops;
@@ -739,6 +492,19 @@ out:
 	return NULL;
 }
 EXPORT_SYMBOL(proc_create_data);
+ 
+void proc_set_size(struct proc_dir_entry *de, loff_t size)
+{
+	de->size = size;
+}
+EXPORT_SYMBOL(proc_set_size);
+
+void proc_set_user(struct proc_dir_entry *de, kuid_t uid, kgid_t gid)
+{
+	de->uid = uid;
+	de->gid = gid;
+}
+EXPORT_SYMBOL(proc_set_user);
 
 static void free_proc_entry(struct proc_dir_entry *de)
 {
@@ -755,41 +521,6 @@ void pde_put(struct proc_dir_entry *pde)
 		free_proc_entry(pde);
 }
 
-static void entry_rundown(struct proc_dir_entry *de)
-{
-	spin_lock(&de->pde_unload_lock);
-	/*
-	 * Stop accepting new callers into module. If you're
-	 * dynamically allocating ->proc_fops, save a pointer somewhere.
-	 */
-	de->proc_fops = NULL;
-	/* Wait until all existing callers into module are done. */
-	if (de->pde_users > 0) {
-		DECLARE_COMPLETION_ONSTACK(c);
-
-		if (!de->pde_unload_completion)
-			de->pde_unload_completion = &c;
-
-		spin_unlock(&de->pde_unload_lock);
-
-		wait_for_completion(de->pde_unload_completion);
-
-		spin_lock(&de->pde_unload_lock);
-	}
-
-	while (!list_empty(&de->pde_openers)) {
-		struct pde_opener *pdeo;
-
-		pdeo = list_first_entry(&de->pde_openers, struct pde_opener, lh);
-		list_del(&pdeo->lh);
-		spin_unlock(&de->pde_unload_lock);
-		pdeo->release(pdeo->inode, pdeo->file);
-		kfree(pdeo);
-		spin_lock(&de->pde_unload_lock);
-	}
-	spin_unlock(&de->pde_unload_lock);
-}
-
 /*
  * Remove a /proc entry and free it if it's not currently in use.
  */
@@ -821,7 +552,7 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
 		return;
 	}
 
-	entry_rundown(de);
+	proc_entry_rundown(de);
 
 	if (S_ISDIR(de->mode))
 		parent->nlink--;
@@ -870,7 +601,7 @@ int remove_proc_subtree(const char *name, struct proc_dir_entry *parent)
 		}
 		spin_unlock(&proc_subdir_lock);
 
-		entry_rundown(de);
+		proc_entry_rundown(de);
 		next = de->parent;
 		if (S_ISDIR(de->mode))
 			next->nlink--;
@@ -886,3 +617,23 @@ int remove_proc_subtree(const char *name, struct proc_dir_entry *parent)
 	return 0;
 }
 EXPORT_SYMBOL(remove_proc_subtree);
+
+void *proc_get_parent_data(const struct inode *inode)
+{
+	struct proc_dir_entry *de = PDE(inode);
+	return de->parent->data;
+}
+EXPORT_SYMBOL_GPL(proc_get_parent_data);
+
+void proc_remove(struct proc_dir_entry *de)
+{
+	if (de)
+		remove_proc_subtree(de->name, de->parent);
+}
+EXPORT_SYMBOL(proc_remove);
+
+void *PDE_DATA(const struct inode *inode)
+{
+	return __PDE_DATA(inode);
+}
+EXPORT_SYMBOL(PDE_DATA);
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 869116c2afb..073aea60cf8 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -22,6 +22,7 @@
 #include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <linux/mount.h>
+#include <linux/magic.h>
 
 #include <asm/uaccess.h>
 
@@ -50,8 +51,8 @@ static void proc_evict_inode(struct inode *inode)
 		sysctl_head_put(head);
 	}
 	/* Release any associated namespace */
-	ns_ops = PROC_I(inode)->ns_ops;
-	ns = PROC_I(inode)->ns;
+	ns_ops = PROC_I(inode)->ns.ns_ops;
+	ns = PROC_I(inode)->ns.ns;
 	if (ns_ops && ns)
 		ns_ops->put(ns);
 }
@@ -72,8 +73,8 @@ static struct inode *proc_alloc_inode(struct super_block *sb)
 	ei->pde = NULL;
 	ei->sysctl = NULL;
 	ei->sysctl_entry = NULL;
-	ei->ns = NULL;
-	ei->ns_ops = NULL;
+	ei->ns.ns = NULL;
+	ei->ns.ns_ops = NULL;
 	inode = &ei->vfs_inode;
 	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 	return inode;
@@ -129,96 +130,100 @@ static const struct super_operations proc_sops = {
 	.show_options	= proc_show_options,
 };
 
-static void __pde_users_dec(struct proc_dir_entry *pde)
+enum {BIAS = -1U<<31};
+
+static inline int use_pde(struct proc_dir_entry *pde)
+{
+	return atomic_inc_unless_negative(&pde->in_use);
+}
+
+static void unuse_pde(struct proc_dir_entry *pde)
 {
-	pde->pde_users--;
-	if (pde->pde_unload_completion && pde->pde_users == 0)
+	if (atomic_dec_return(&pde->in_use) == BIAS)
 		complete(pde->pde_unload_completion);
 }
 
-void pde_users_dec(struct proc_dir_entry *pde)
+/* pde is locked */
+static void close_pdeo(struct proc_dir_entry *pde, struct pde_opener *pdeo)
 {
-	spin_lock(&pde->pde_unload_lock);
-	__pde_users_dec(pde);
-	spin_unlock(&pde->pde_unload_lock);
+	if (pdeo->closing) {
+		/* somebody else is doing that, just wait */
+		DECLARE_COMPLETION_ONSTACK(c);
+		pdeo->c = &c;
+		spin_unlock(&pde->pde_unload_lock);
+		wait_for_completion(&c);
+		spin_lock(&pde->pde_unload_lock);
+	} else {
+		struct file *file;
+		pdeo->closing = 1;
+		spin_unlock(&pde->pde_unload_lock);
+		file = pdeo->file;
+		pde->proc_fops->release(file_inode(file), file);
+		spin_lock(&pde->pde_unload_lock);
+		list_del_init(&pdeo->lh);
+		if (pdeo->c)
+			complete(pdeo->c);
+		kfree(pdeo);
+	}
+}
+
+void proc_entry_rundown(struct proc_dir_entry *de)
+{
+	DECLARE_COMPLETION_ONSTACK(c);
+	/* Wait until all existing callers into module are done. */
+	de->pde_unload_completion = &c;
+	if (atomic_add_return(BIAS, &de->in_use) != BIAS)
+		wait_for_completion(&c);
+
+	spin_lock(&de->pde_unload_lock);
+	while (!list_empty(&de->pde_openers)) {
+		struct pde_opener *pdeo;
+		pdeo = list_first_entry(&de->pde_openers, struct pde_opener, lh);
+		close_pdeo(de, pdeo);
+	}
+	spin_unlock(&de->pde_unload_lock);
 }
 
 static loff_t proc_reg_llseek(struct file *file, loff_t offset, int whence)
 {
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	loff_t rv = -EINVAL;
-	loff_t (*llseek)(struct file *, loff_t, int);
-
-	spin_lock(&pde->pde_unload_lock);
-	/*
-	 * remove_proc_entry() is going to delete PDE (as part of module
-	 * cleanup sequence). No new callers into module allowed.
-	 */
-	if (!pde->proc_fops) {
-		spin_unlock(&pde->pde_unload_lock);
-		return rv;
+	if (use_pde(pde)) {
+		loff_t (*llseek)(struct file *, loff_t, int);
+		llseek = pde->proc_fops->llseek;
+		if (!llseek)
+			llseek = default_llseek;
+		rv = llseek(file, offset, whence);
+		unuse_pde(pde);
 	}
-	/*
-	 * Bump refcount so that remove_proc_entry will wail for ->llseek to
-	 * complete.
-	 */
-	pde->pde_users++;
-	/*
-	 * Save function pointer under lock, to protect against ->proc_fops
-	 * NULL'ifying right after ->pde_unload_lock is dropped.
-	 */
-	llseek = pde->proc_fops->llseek;
-	spin_unlock(&pde->pde_unload_lock);
-
-	if (!llseek)
-		llseek = default_llseek;
-	rv = llseek(file, offset, whence);
-
-	pde_users_dec(pde);
 	return rv;
 }
 
 static ssize_t proc_reg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 {
+	ssize_t (*read)(struct file *, char __user *, size_t, loff_t *);
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	ssize_t rv = -EIO;
-	ssize_t (*read)(struct file *, char __user *, size_t, loff_t *);
-
-	spin_lock(&pde->pde_unload_lock);
-	if (!pde->proc_fops) {
-		spin_unlock(&pde->pde_unload_lock);
-		return rv;
+	if (use_pde(pde)) {
+		read = pde->proc_fops->read;
+		if (read)
+			rv = read(file, buf, count, ppos);
+		unuse_pde(pde);
 	}
-	pde->pde_users++;
-	read = pde->proc_fops->read;
-	spin_unlock(&pde->pde_unload_lock);
-
-	if (read)
-		rv = read(file, buf, count, ppos);
-
-	pde_users_dec(pde);
 	return rv;
 }
 
 static ssize_t proc_reg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 {
+	ssize_t (*write)(struct file *, const char __user *, size_t, loff_t *);
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	ssize_t rv = -EIO;
-	ssize_t (*write)(struct file *, const char __user *, size_t, loff_t *);
-
-	spin_lock(&pde->pde_unload_lock);
-	if (!pde->proc_fops) {
-		spin_unlock(&pde->pde_unload_lock);
-		return rv;
+	if (use_pde(pde)) {
+		write = pde->proc_fops->write;
+		if (write)
+			rv = write(file, buf, count, ppos);
+		unuse_pde(pde);
 	}
-	pde->pde_users++;
-	write = pde->proc_fops->write;
-	spin_unlock(&pde->pde_unload_lock);
-
-	if (write)
-		rv = write(file, buf, count, ppos);
-
-	pde_users_dec(pde);
 	return rv;
 }
 
@@ -227,20 +232,12 @@ static unsigned int proc_reg_poll(struct file *file, struct poll_table_struct *p
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	unsigned int rv = DEFAULT_POLLMASK;
 	unsigned int (*poll)(struct file *, struct poll_table_struct *);
-
-	spin_lock(&pde->pde_unload_lock);
-	if (!pde->proc_fops) {
-		spin_unlock(&pde->pde_unload_lock);
-		return rv;
+	if (use_pde(pde)) {
+		poll = pde->proc_fops->poll;
+		if (poll)
+			rv = poll(file, pts);
+		unuse_pde(pde);
 	}
-	pde->pde_users++;
-	poll = pde->proc_fops->poll;
-	spin_unlock(&pde->pde_unload_lock);
-
-	if (poll)
-		rv = poll(file, pts);
-
-	pde_users_dec(pde);
 	return rv;
 }
 
@@ -249,20 +246,12 @@ static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigne
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	long rv = -ENOTTY;
 	long (*ioctl)(struct file *, unsigned int, unsigned long);
-
-	spin_lock(&pde->pde_unload_lock);
-	if (!pde->proc_fops) {
-		spin_unlock(&pde->pde_unload_lock);
-		return rv;
+	if (use_pde(pde)) {
+		ioctl = pde->proc_fops->unlocked_ioctl;
+		if (ioctl)
+			rv = ioctl(file, cmd, arg);
+		unuse_pde(pde);
 	}
-	pde->pde_users++;
-	ioctl = pde->proc_fops->unlocked_ioctl;
-	spin_unlock(&pde->pde_unload_lock);
-
-	if (ioctl)
-		rv = ioctl(file, cmd, arg);
-
-	pde_users_dec(pde);
 	return rv;
 }
 
@@ -272,20 +261,12 @@ static long proc_reg_compat_ioctl(struct file *file, unsigned int cmd, unsigned
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	long rv = -ENOTTY;
 	long (*compat_ioctl)(struct file *, unsigned int, unsigned long);
-
-	spin_lock(&pde->pde_unload_lock);
-	if (!pde->proc_fops) {
-		spin_unlock(&pde->pde_unload_lock);
-		return rv;
+	if (use_pde(pde)) {
+		compat_ioctl = pde->proc_fops->compat_ioctl;
+		if (compat_ioctl)
+			rv = compat_ioctl(file, cmd, arg);
+		unuse_pde(pde);
 	}
-	pde->pde_users++;
-	compat_ioctl = pde->proc_fops->compat_ioctl;
-	spin_unlock(&pde->pde_unload_lock);
-
-	if (compat_ioctl)
-		rv = compat_ioctl(file, cmd, arg);
-
-	pde_users_dec(pde);
 	return rv;
 }
 #endif
@@ -295,20 +276,12 @@ static int proc_reg_mmap(struct file *file, struct vm_area_struct *vma)
 	struct proc_dir_entry *pde = PDE(file_inode(file));
 	int rv = -EIO;
 	int (*mmap)(struct file *, struct vm_area_struct *);
-
-	spin_lock(&pde->pde_unload_lock);
-	if (!pde->proc_fops) {
-		spin_unlock(&pde->pde_unload_lock);
-		return rv;
+	if (use_pde(pde)) {
+		mmap = pde->proc_fops->mmap;
+		if (mmap)
+			rv = mmap(file, vma);
+		unuse_pde(pde);
 	}
-	pde->pde_users++;
-	mmap = pde->proc_fops->mmap;
-	spin_unlock(&pde->pde_unload_lock);
-
-	if (mmap)
-		rv = mmap(file, vma);
-
-	pde_users_dec(pde);
 	return rv;
 }
 
@@ -330,91 +303,47 @@ static int proc_reg_open(struct inode *inode, struct file *file)
 	 * by hand in remove_proc_entry(). For this, save opener's credentials
 	 * for later.
 	 */
-	pdeo = kmalloc(sizeof(struct pde_opener), GFP_KERNEL);
+	pdeo = kzalloc(sizeof(struct pde_opener), GFP_KERNEL);
 	if (!pdeo)
 		return -ENOMEM;
 
-	spin_lock(&pde->pde_unload_lock);
-	if (!pde->proc_fops) {
-		spin_unlock(&pde->pde_unload_lock);
+	if (!use_pde(pde)) {
 		kfree(pdeo);
 		return -ENOENT;
 	}
-	pde->pde_users++;
 	open = pde->proc_fops->open;
 	release = pde->proc_fops->release;
-	spin_unlock(&pde->pde_unload_lock);
 
 	if (open)
 		rv = open(inode, file);
 
-	spin_lock(&pde->pde_unload_lock);
 	if (rv == 0 && release) {
 		/* To know what to release. */
-		pdeo->inode = inode;
 		pdeo->file = file;
 		/* Strictly for "too late" ->release in proc_reg_release(). */
-		pdeo->release = release;
+		spin_lock(&pde->pde_unload_lock);
 		list_add(&pdeo->lh, &pde->pde_openers);
+		spin_unlock(&pde->pde_unload_lock);
 	} else
 		kfree(pdeo);
-	__pde_users_dec(pde);
-	spin_unlock(&pde->pde_unload_lock);
-	return rv;
-}
-
-static struct pde_opener *find_pde_opener(struct proc_dir_entry *pde,
-					struct inode *inode, struct file *file)
-{
-	struct pde_opener *pdeo;
 
-	list_for_each_entry(pdeo, &pde->pde_openers, lh) {
-		if (pdeo->inode == inode && pdeo->file == file)
-			return pdeo;
-	}
-	return NULL;
+	unuse_pde(pde);
+	return rv;
 }
 
 static int proc_reg_release(struct inode *inode, struct file *file)
 {
 	struct proc_dir_entry *pde = PDE(inode);
-	int rv = 0;
-	int (*release)(struct inode *, struct file *);
 	struct pde_opener *pdeo;
-
 	spin_lock(&pde->pde_unload_lock);
-	pdeo = find_pde_opener(pde, inode, file);
-	if (!pde->proc_fops) {
-		/*
-		 * Can't simply exit, __fput() will think that everything is OK,
-		 * and move on to freeing struct file. remove_proc_entry() will
-		 * find slacker in opener's list and will try to do non-trivial
-		 * things with struct file. Therefore, remove opener from list.
-		 *
-		 * But if opener is removed from list, who will ->release it?
-		 */
-		if (pdeo) {
-			list_del(&pdeo->lh);
-			spin_unlock(&pde->pde_unload_lock);
-			rv = pdeo->release(inode, file);
-			kfree(pdeo);
-		} else
-			spin_unlock(&pde->pde_unload_lock);
-		return rv;
-	}
-	pde->pde_users++;
-	release = pde->proc_fops->release;
-	if (pdeo) {
-		list_del(&pdeo->lh);
-		kfree(pdeo);
+	list_for_each_entry(pdeo, &pde->pde_openers, lh) {
+		if (pdeo->file == file) {
+			close_pdeo(pde, pdeo);
+			break;
+		}
 	}
 	spin_unlock(&pde->pde_unload_lock);
-
-	if (release)
-		rv = release(inode, file);
-
-	pde_users_dec(pde);
-	return rv;
+	return 0;
 }
 
 static const struct file_operations proc_reg_file_ops = {
@@ -462,8 +391,8 @@ struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de)
 			inode->i_size = de->size;
 		if (de->nlink)
 			set_nlink(inode, de->nlink);
-		if (de->proc_iops)
-			inode->i_op = de->proc_iops;
+		WARN_ON(!de->proc_iops);
+		inode->i_op = de->proc_iops;
 		if (de->proc_fops) {
 			if (S_ISREG(inode->i_mode)) {
 #ifdef CONFIG_COMPAT
@@ -506,5 +435,5 @@ int proc_fill_super(struct super_block *s)
 		return -ENOMEM;
 	}
 
-	return 0;
+	return proc_setup_self(s);
 }
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index 75710357a51..d600fb098b6 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -1,4 +1,4 @@
-/* internal.h: internal procfs definitions
+/* Internal procfs definitions
  *
  * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
@@ -9,62 +9,83 @@
  * 2 of the License, or (at your option) any later version.
  */
 
-#include <linux/sched.h>
 #include <linux/proc_fs.h>
+#include <linux/proc_ns.h>
+#include <linux/spinlock.h>
+#include <linux/atomic.h>
 #include <linux/binfmts.h>
-struct  ctl_table_header;
-struct  mempolicy;
 
-extern struct proc_dir_entry proc_root;
-extern void proc_self_init(void);
-#ifdef CONFIG_PROC_SYSCTL
-extern int proc_sys_init(void);
-extern void sysctl_head_put(struct ctl_table_header *head);
-#else
-static inline void proc_sys_init(void) { }
-static inline void sysctl_head_put(struct ctl_table_header *head) { }
-#endif
-#ifdef CONFIG_NET
-extern int proc_net_init(v