From 5f5715c31f4f472060af5aa205133b9a693b42c4 Mon Sep 17 00:00:00 2001
From: Marc Fiuczynski <mef@cs.princeton.edu>
Date: Tue, 9 Aug 2005 01:08:03 +0000
Subject: [PATCH] should not have made it onto the tree

---
 fs/namespace.c~ | 1548 -----------------------------------------------
 1 file changed, 1548 deletions(-)
 delete mode 100644 fs/namespace.c~

diff --git a/fs/namespace.c~ b/fs/namespace.c~
deleted file mode 100644
index e1f8b7318..000000000
--- a/fs/namespace.c~
+++ /dev/null
@@ -1,1548 +0,0 @@
-/*
- *  linux/fs/namespace.c
- *
- * (C) Copyright Al Viro 2000, 2001
- *	Released under GPL v2.
- *
- * Based on code from fs/super.c, copyright Linus Torvalds and others.
- * Heavily rewritten.
- */
-
-#include <linux/config.h>
-#include <linux/syscalls.h>
-#include <linux/slab.h>
-#include <linux/sched.h>
-#include <linux/smp_lock.h>
-#include <linux/init.h>
-#include <linux/quotaops.h>
-#include <linux/acct.h>
-#include <linux/module.h>
-#include <linux/seq_file.h>
-#include <linux/namespace.h>
-#include <linux/namei.h>
-#include <linux/security.h>
-#include <linux/mount.h>
-#include <linux/vserver/namespace.h>
-#include <linux/vserver/xid.h>
-
-#include <asm/uaccess.h>
-#include <asm/unistd.h>
-
-extern int __init init_rootfs(void);
-
-#ifdef CONFIG_SYSFS
-extern int __init sysfs_init(void);
-#else
-static inline int sysfs_init(void)
-{
-	return 0;
-}
-#endif
-
-/* spinlock for vfsmount related operations, inplace of dcache_lock */
- __cacheline_aligned_in_smp DEFINE_SPINLOCK(vfsmount_lock);
-
-static struct list_head *mount_hashtable;
-static int hash_mask, hash_bits;
-static kmem_cache_t *mnt_cache; 
-
-static inline unsigned long hash(struct vfsmount *mnt, struct dentry *dentry)
-{
-	unsigned long tmp = ((unsigned long) mnt / L1_CACHE_BYTES);
-	tmp += ((unsigned long) dentry / L1_CACHE_BYTES);
-	tmp = tmp + (tmp >> hash_bits);
-	return tmp & hash_mask;
-}
-
-struct vfsmount *alloc_vfsmnt(const char *name)
-{
-	struct vfsmount *mnt = kmem_cache_alloc(mnt_cache, GFP_KERNEL); 
-	if (mnt) {
-		memset(mnt, 0, sizeof(struct vfsmount));
-		atomic_set(&mnt->mnt_count,1);
-		INIT_LIST_HEAD(&mnt->mnt_hash);
-		INIT_LIST_HEAD(&mnt->mnt_child);
-		INIT_LIST_HEAD(&mnt->mnt_mounts);
-		INIT_LIST_HEAD(&mnt->mnt_list);
-		INIT_LIST_HEAD(&mnt->mnt_fslink);
-		if (name) {
-			int size = strlen(name)+1;
-			char *newname = kmalloc(size, GFP_KERNEL);
-			if (newname) {
-				memcpy(newname, name, size);
-				mnt->mnt_devname = newname;
-			}
-		}
-	}
-	return mnt;
-}
-
-void free_vfsmnt(struct vfsmount *mnt)
-{
-	kfree(mnt->mnt_devname);
-	kmem_cache_free(mnt_cache, mnt);
-}
-
-/*
- * Now, lookup_mnt increments the ref count before returning
- * the vfsmount struct.
- */
-struct vfsmount *lookup_mnt(struct vfsmount *mnt, struct dentry *dentry)
-{
-	struct list_head * head = mount_hashtable + hash(mnt, dentry);
-	struct list_head * tmp = head;
-	struct vfsmount *p, *found = NULL;
-
-	spin_lock(&vfsmount_lock);
-	for (;;) {
-		tmp = tmp->next;
-		p = NULL;
-		if (tmp == head)
-			break;
-		p = list_entry(tmp, struct vfsmount, mnt_hash);
-		if (p->mnt_parent == mnt && p->mnt_mountpoint == dentry) {
-			found = mntget(p);
-			break;
-		}
-	}
-	spin_unlock(&vfsmount_lock);
-	return found;
-}
-
-static inline int check_mnt(struct vfsmount *mnt)
-{
-	return mnt->mnt_namespace == current->namespace;
-}
-
-static void detach_mnt(struct vfsmount *mnt, struct nameidata *old_nd)
-{
-	old_nd->dentry = mnt->mnt_mountpoint;
-	old_nd->mnt = mnt->mnt_parent;
-	mnt->mnt_parent = mnt;
-	mnt->mnt_mountpoint = mnt->mnt_root;
-	list_del_init(&mnt->mnt_child);
-	list_del_init(&mnt->mnt_hash);
-	old_nd->dentry->d_mounted--;
-}
-
-static void attach_mnt(struct vfsmount *mnt, struct nameidata *nd)
-{
-	mnt->mnt_parent = mntget(nd->mnt);
-	mnt->mnt_mountpoint = dget(nd->dentry);
-	list_add(&mnt->mnt_hash, mount_hashtable+hash(nd->mnt, nd->dentry));
-	list_add_tail(&mnt->mnt_child, &nd->mnt->mnt_mounts);
-	nd->dentry->d_mounted++;
-}
-
-static struct vfsmount *next_mnt(struct vfsmount *p, struct vfsmount *root)
-{
-	struct list_head *next = p->mnt_mounts.next;
-	if (next == &p->mnt_mounts) {
-		while (1) {
-			if (p == root)
-				return NULL;
-			next = p->mnt_child.next;
-			if (next != &p->mnt_parent->mnt_mounts)
-				break;
-			p = p->mnt_parent;
-		}
-	}
-	return list_entry(next, struct vfsmount, mnt_child);
-}
-
-static struct vfsmount *
-clone_mnt(struct vfsmount *old, struct dentry *root)
-{
-	struct super_block *sb = old->mnt_sb;
-	struct vfsmount *mnt = alloc_vfsmnt(old->mnt_devname);
-
-	if (mnt) {
-		mnt->mnt_flags = old->mnt_flags;
-		atomic_inc(&sb->s_active);
-		mnt->mnt_sb = sb;
-		mnt->mnt_root = dget(root);
-		mnt->mnt_mountpoint = mnt->mnt_root;
-		mnt->mnt_parent = mnt;
-		mnt->mnt_namespace = old->mnt_namespace;
-		mnt->mnt_xid = old->mnt_xid;
-
-		/* stick the duplicate mount on the same expiry list
-		 * as the original if that was on one */
-		spin_lock(&vfsmount_lock);
-		if (!list_empty(&old->mnt_fslink))
-			list_add(&mnt->mnt_fslink, &old->mnt_fslink);
-		spin_unlock(&vfsmount_lock);
-	}
-	return mnt;
-}
-
-void __mntput(struct vfsmount *mnt)
-{
-	struct super_block *sb = mnt->mnt_sb;
-	dput(mnt->mnt_root);
-	free_vfsmnt(mnt);
-	deactivate_super(sb);
-}
-
-EXPORT_SYMBOL(__mntput);
-
-/* iterator */
-static void *m_start(struct seq_file *m, loff_t *pos)
-{
-	struct namespace *n = m->private;
-	struct list_head *p;
-	loff_t l = *pos;
-
-	down_read(&n->sem);
-	list_for_each(p, &n->list)
-		if (!l--)
-			return list_entry(p, struct vfsmount, mnt_list);
-	return NULL;
-}
-
-static void *m_next(struct seq_file *m, void *v, loff_t *pos)
-{
-	struct namespace *n = m->private;
-	struct list_head *p = ((struct vfsmount *)v)->mnt_list.next;
-	(*pos)++;
-	return p==&n->list ? NULL : list_entry(p, struct vfsmount, mnt_list);
-}
-
-static void m_stop(struct seq_file *m, void *v)
-{
-	struct namespace *n = m->private;
-	up_read(&n->sem);
-}
-
-static inline void mangle(struct seq_file *m, const char *s)
-{
-	seq_escape(m, s, " \t\n\\");
-}
-
-static int mnt_is_reachable(struct vfsmount *mnt)
-{
-	struct vfsmount *root_mnt;
-	struct dentry *root, *point;
-	int ret;
-
-	if (!mnt)
-		return 1;
-	if (mnt == mnt->mnt_namespace->root)
-		return 1;
-
-	spin_lock(&dcache_lock);
-	root_mnt = current->fs->rootmnt;
-	root = current->fs->root;
-	point = root;
-
-	while ((mnt != mnt->mnt_parent) && (mnt != root_mnt)) {
-		point = mnt->mnt_mountpoint;
-		mnt = mnt->mnt_parent;
-	}
-
-	ret = (mnt == root_mnt) && is_subdir(point, root);
-
-	spin_unlock(&dcache_lock);
-
-	return ret;
-}
-
-static int show_vfsmnt(struct seq_file *m, void *v)
-{
-	struct vfsmount *mnt = v;
-	int err = 0;
-	static struct proc_fs_info {
-		int flag;
-		char *str;
-	} fs_info[] = {
-		{ MS_SYNCHRONOUS, ",sync" },
-		{ MS_DIRSYNC, ",dirsync" },
-		{ MS_MANDLOCK, ",mand" },
-		{ MS_NOATIME, ",noatime" },
-		{ MS_NODIRATIME, ",nodiratime" },
-		{ MS_TAGXID, ",tagxid" },
-		{ 0, NULL }
-	};
-	static struct proc_fs_info mnt_info[] = {
-		{ MNT_NOSUID, ",nosuid" },
-		{ MNT_NODEV, ",nodev" },
-		{ MNT_NOEXEC, ",noexec" },
-		{ 0, NULL }
-	};
-	struct proc_fs_info *fs_infop;
-
-	if (vx_flags(VXF_HIDE_MOUNT, 0))
-		return 0;
-	if (!mnt_is_reachable(mnt))
-		return 0;
-
-	if (!vx_check(0, VX_ADMIN|VX_WATCH) &&
-		mnt == current->fs->rootmnt) {
-		seq_puts(m, "/dev/root / ");
-	} else {
-		mangle(m, mnt->mnt_devname ? mnt->mnt_devname : "none");
-		seq_putc(m, ' ');
-		seq_path(m, mnt, mnt->mnt_root, " \t\n\\");
-		seq_putc(m, ' ');
-	}
-	mangle(m, mnt->mnt_sb->s_type->name);
-	seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? " ro" : " rw");
-	for (fs_infop = fs_info; fs_infop->flag; fs_infop++) {
-		if (mnt->mnt_sb->s_flags & fs_infop->flag)
-			seq_puts(m, fs_infop->str);
-	}
-	for (fs_infop = mnt_info; fs_infop->flag; fs_infop++) {
-		if (mnt->mnt_flags & fs_infop->flag)
-			seq_puts(m, fs_infop->str);
-	}
-	if (mnt->mnt_flags & MNT_XID)
-		seq_printf(m, ",xid=%d", mnt->mnt_xid);
-	if (mnt->mnt_sb->s_op->show_options)
-		err = mnt->mnt_sb->s_op->show_options(m, mnt);
-	seq_puts(m, " 0 0\n");
-	return err;
-}
-
-struct seq_operations mounts_op = {
-	.start	= m_start,
-	.next	= m_next,
-	.stop	= m_stop,
-	.show	= show_vfsmnt
-};
-
-/**
- * may_umount_tree - check if a mount tree is busy
- * @mnt: root of mount tree
- *
- * This is called to check if a tree of mounts has any
- * open files, pwds, chroots or sub mounts that are
- * busy.
- */
-int may_umount_tree(struct vfsmount *mnt)
-{
-	struct list_head *next;
-	struct vfsmount *this_parent = mnt;
-	int actual_refs;
-	int minimum_refs;
-
-	spin_lock(&vfsmount_lock);
-	actual_refs = atomic_read(&mnt->mnt_count);
-	minimum_refs = 2;
-repeat:
-	next = this_parent->mnt_mounts.next;
-resume:
-	while (next != &this_parent->mnt_mounts) {
-		struct vfsmount *p = list_entry(next, struct vfsmount, mnt_child);
-
-		next = next->next;
-
-		actual_refs += atomic_read(&p->mnt_count);
-		minimum_refs += 2;
-
-		if (!list_empty(&p->mnt_mounts)) {
-			this_parent = p;
-			goto repeat;
-		}
-	}
-
-	if (this_parent != mnt) {
-		next = this_parent->mnt_child.next;
-		this_parent = this_parent->mnt_parent;
-		goto resume;
-	}
-	spin_unlock(&vfsmount_lock);
-
-	if (actual_refs > minimum_refs)
-		return -EBUSY;
-
-	return 0;
-}
-
-EXPORT_SYMBOL(may_umount_tree);
-
-/**
- * may_umount - check if a mount point is busy
- * @mnt: root of mount
- *
- * This is called to check if a mount point has any
- * open files, pwds, chroots or sub mounts. If the
- * mount has sub mounts this will return busy
- * regardless of whether the sub mounts are busy.
- *
- * Doesn't take quota and stuff into account. IOW, in some cases it will
- * give false negatives. The main reason why it's here is that we need
- * a non-destructive way to look for easily umountable filesystems.
- */
-int may_umount(struct vfsmount *mnt)
-{
-	if (atomic_read(&mnt->mnt_count) > 2)
-		return -EBUSY;
-	return 0;
-}
-
-EXPORT_SYMBOL(may_umount);
-
-static inline void __umount_list(struct list_head *kill)
-{
-	struct vfsmount *mnt;
-
-	while (!list_empty(kill)) {
-		mnt = list_entry(kill->next, struct vfsmount, mnt_list);
-		list_del_init(&mnt->mnt_list);
-		list_del_init(&mnt->mnt_fslink);
-		if (mnt->mnt_parent == mnt) {
-			spin_unlock(&vfsmount_lock);
-		} else {
-			struct nameidata old_nd;
-			detach_mnt(mnt, &old_nd);
-			spin_unlock(&vfsmount_lock);
-			path_release(&old_nd);
-		}
-		mntput(mnt);
-		spin_lock(&vfsmount_lock);
-	}
-}
-
-void umount_tree(struct vfsmount *mnt)
-{
-	struct vfsmount *p;
-	LIST_HEAD(kill);
-
-	for (p = mnt; p; p = next_mnt(p, mnt)) {
-		list_del(&p->mnt_list);
-		list_add(&p->mnt_list, &kill);
-	}
-	__umount_list(&kill);
-}
-
-void umount_unused(struct vfsmount *mnt, struct fs_struct *fs)
-{
-	struct vfsmount *p;
-	LIST_HEAD(kill);
-
-	for (p = mnt; p; p = next_mnt(p, mnt)) {
-		if (p == fs->rootmnt || p == fs->pwdmnt)
-			continue;
-		list_del(&p->mnt_list);
-		list_add(&p->mnt_list, &kill);
-	}
-	__umount_list(&kill);
-}
-
-static int do_umount(struct vfsmount *mnt, int flags)
-{
-	struct super_block * sb = mnt->mnt_sb;
-	int retval;
-
-	retval = security_sb_umount(mnt, flags);
-	if (retval)
-		return retval;
-
-	/*
-	 * Allow userspace to request a mountpoint be expired rather than
-	 * unmounting unconditionally. Unmount only happens if:
-	 *  (1) the mark is already set (the mark is cleared by mntput())
-	 *  (2) the usage count == 1 [parent vfsmount] + 1 [sys_umount]
-	 */
-	if (flags & MNT_EXPIRE) {
-		if (mnt == current->fs->rootmnt ||
-		    flags & (MNT_FORCE | MNT_DETACH))
-			return -EINVAL;
-
-		if (atomic_read(&mnt->mnt_count) != 2)
-			return -EBUSY;
-
-		if (!xchg(&mnt->mnt_expiry_mark, 1))
-			return -EAGAIN;
-	}
-
-	/*
-	 * If we may have to abort operations to get out of this
-	 * mount, and they will themselves hold resources we must
-	 * allow the fs to do things. In the Unix tradition of
-	 * 'Gee thats tricky lets do it in userspace' the umount_begin
-	 * might fail to complete on the first run through as other tasks
-	 * must return, and the like. Thats for the mount program to worry
-	 * about for the moment.
-	 */
-
-	lock_kernel();
-	if( (flags&MNT_FORCE) && sb->s_op->umount_begin)
-		sb->s_op->umount_begin(sb);
-	unlock_kernel();
-
-	/*
-	 * No sense to grab the lock for this test, but test itself looks
-	 * somewhat bogus. Suggestions for better replacement?
-	 * Ho-hum... In principle, we might treat that as umount + switch
-	 * to rootfs. GC would eventually take care of the old vfsmount.
-	 * Actually it makes sense, especially if rootfs would contain a
-	 * /reboot - static binary that would close all descriptors and
-	 * call reboot(9). Then init(8) could umount root and exec /reboot.
-	 */
-	if (mnt == current->fs->rootmnt && !(flags & MNT_DETACH)) {
-		/*
-		 * Special case for "unmounting" root ...
-		 * we just try to remount it readonly.
-		 */
-		down_write(&sb->s_umount);
-		if (!(sb->s_flags & MS_RDONLY)) {
-			lock_kernel();
-			DQUOT_OFF(sb);
-			retval = do_remount_sb(sb, MS_RDONLY, NULL, 0);
-			unlock_kernel();
-		}
-		up_write(&sb->s_umount);
-		return retval;
-	}
-
-	down_write(&current->namespace->sem);
-	spin_lock(&vfsmount_lock);
-
-	if (atomic_read(&sb->s_active) == 1) {
-		/* last instance - try to be smart */
-		spin_unlock(&vfsmount_lock);
-		lock_kernel();
-		DQUOT_OFF(sb);
-		acct_auto_close(sb);
-		unlock_kernel();
-		security_sb_umount_close(mnt);
-		spin_lock(&vfsmount_lock);
-	}
-	retval = -EBUSY;
-	if (atomic_read(&mnt->mnt_count) == 2 || flags & MNT_DETACH) {
-		if (!list_empty(&mnt->mnt_list))
-			umount_tree(mnt);
-		retval = 0;
-	}
-	spin_unlock(&vfsmount_lock);
-	if (retval)
-		security_sb_umount_busy(mnt);
-	up_write(&current->namespace->sem);
-	return retval;
-}
-
-/*
- * Now umount can handle mount points as well as block devices.
- * This is important for filesystems which use unnamed block devices.
- *
- * We now support a flag for forced unmount like the other 'big iron'
- * unixes. Our API is identical to OSF/1 to avoid making a mess of AMD
- */
-
-asmlinkage long sys_umount(char __user * name, int flags)
-{
-	struct nameidata nd;
-	int retval;
-
-	retval = __user_walk(name, LOOKUP_FOLLOW, &nd);
-	if (retval)
-		goto out;
-	retval = -EINVAL;
-	if (nd.dentry != nd.mnt->mnt_root)
-		goto dput_and_out;
-	if (!check_mnt(nd.mnt))
-		goto dput_and_out;
-
-	retval = -EPERM;
-	if (!capable(CAP_SYS_ADMIN) && !vx_ccaps(VXC_SECURE_MOUNT))
-		goto dput_and_out;
-
-	retval = do_umount(nd.mnt, flags);
-dput_and_out:
-	path_release_on_umount(&nd);
-out:
-	return retval;
-}
-
-#ifdef __ARCH_WANT_SYS_OLDUMOUNT
-
-/*
- *	The 2.0 compatible umount. No flags. 
- */
- 
-asmlinkage long sys_oldumount(char __user * name)
-{
-	return sys_umount(name,0);
-}
-
-#endif
-
-static int mount_is_safe(struct nameidata *nd)
-{
-	if (capable(CAP_SYS_ADMIN))
-		return 0;
-	if (vx_ccaps(VXC_SECURE_MOUNT))
-		return 0;
-	return -EPERM;
-#ifdef notyet
-	if (S_ISLNK(nd->dentry->d_inode->i_mode))
-		return -EPERM;
-	if (nd->dentry->d_inode->i_mode & S_ISVTX) {
-		if (current->uid != nd->dentry->d_inode->i_uid)
-			return -EPERM;
-	}
-	if (permission(nd->dentry->d_inode, MAY_WRITE, nd))
-		return -EPERM;
-	return 0;
-#endif
-}
-
-static int
-lives_below_in_same_fs(struct dentry *d, struct dentry *dentry)
-{
-	while (1) {
-		if (d == dentry)
-			return 1;
-		if (d == NULL || d == d->d_parent)
-			return 0;
-		d = d->d_parent;
-	}
-}
-
-static struct vfsmount *copy_tree(struct vfsmount *mnt, struct dentry *dentry)
-{
-	struct vfsmount *res, *p, *q, *r, *s;
-	struct list_head *h;
-	struct nameidata nd;
-
-	res = q = clone_mnt(mnt, dentry);
-	if (!q)
-		goto Enomem;
-	q->mnt_mountpoint = mnt->mnt_mountpoint;
-
-	p = mnt;
-	for (h = mnt->mnt_mounts.next; h != &mnt->mnt_mounts; h = h->next) {
-		r = list_entry(h, struct vfsmount, mnt_child);
-		if (!lives_below_in_same_fs(r->mnt_mountpoint, dentry))
-			continue;
-
-		for (s = r; s; s = next_mnt(s, r)) {
-			while (p != s->mnt_parent) {
-				p = p->mnt_parent;
-				q = q->mnt_parent;
-			}
-			p = s;
-			nd.mnt = q;
-			nd.dentry = p->mnt_mountpoint;
-			q = clone_mnt(p, p->mnt_root);
-			if (!q)
-				goto Enomem;
-			spin_lock(&vfsmount_lock);
-			list_add_tail(&q->mnt_list, &res->mnt_list);
-			attach_mnt(q, &nd);
-			spin_unlock(&vfsmount_lock);
-		}
-	}
-	return res;
- Enomem:
-	if (res) {
-		spin_lock(&vfsmount_lock);
-		umount_tree(res);
-		spin_unlock(&vfsmount_lock);
-	}
-	return NULL;
-}
-
-static int graft_tree(struct vfsmount *mnt, struct nameidata *nd)
-{
-	int err;
-	if (mnt->mnt_sb->s_flags & MS_NOUSER)
-		return -EINVAL;
-
-	if (S_ISDIR(nd->dentry->d_inode->i_mode) !=
-	      S_ISDIR(mnt->mnt_root->d_inode->i_mode))
-		return -ENOTDIR;
-
-	err = -ENOENT;
-	down(&nd->dentry->d_inode->i_sem);
-	if (IS_DEADDIR(nd->dentry->d_inode))
-		goto out_unlock;
-
-	err = security_sb_check_sb(mnt, nd);
-	if (err)
-		goto out_unlock;
-
-	err = -ENOENT;
-	spin_lock(&vfsmount_lock);
-	if (IS_ROOT(nd->dentry) || !d_unhashed(nd->dentry)) {
-		struct list_head head;
-
-		attach_mnt(mnt, nd);
-		list_add_tail(&head, &mnt->mnt_list);
-		list_splice(&head, current->namespace->list.prev);
-		mntget(mnt);
-		err = 0;
-	}
-	spin_unlock(&vfsmount_lock);
-out_unlock:
-	up(&nd->dentry->d_inode->i_sem);
-	if (!err)
-		security_sb_post_addmount(mnt, nd);
-	return err;
-}
-
-/*
- * do loopback mount.
- */
-static int do_loopback(struct nameidata *nd, char *old_name, xid_t xid, int flags)
-{
-	struct nameidata old_nd;
-	struct vfsmount *mnt = NULL;
-	int err = mount_is_safe(nd);
-	int recurse = flags & MS_REC;
-	if (err)
-		return err;
-	if (!old_name || !*old_name)
-		return -EINVAL;
-	err = path_lookup(old_name, LOOKUP_FOLLOW, &old_nd);
-	if (err)
-		return err;
-
-	down_write(&current->namespace->sem);
-	err = -EINVAL;
-	if (check_mnt(nd->mnt) && (!recurse || check_mnt(old_nd.mnt))) {
-		err = -ENOMEM;
-		if (recurse)
-			mnt = copy_tree(old_nd.mnt, old_nd.dentry);
-		else
-			mnt = clone_mnt(old_nd.mnt, old_nd.dentry);
-	}
-
-	if (mnt) {
-		/* stop bind mounts from expiring */
-		spin_lock(&vfsmount_lock);
-		list_del_init(&mnt->mnt_fslink);
-		spin_unlock(&vfsmount_lock);
-
-		if (flags & MS_XID) {
-			mnt->mnt_xid = xid;
-			mnt->mnt_flags |= MNT_XID;
-		}
-		err = graft_tree(mnt, nd);
-		if (err) {
-			spin_lock(&vfsmount_lock);
-			umount_tree(mnt);
-			spin_unlock(&vfsmount_lock);
-		} else
-			mntput(mnt);
-	}
-
-	up_write(&current->namespace->sem);
-	path_release(&old_nd);
-	return err;
-}
-
-/*
- * change filesystem flags. dir should be a physical root of filesystem.
- * If you've mounted a non-root directory somewhere and want to do remount
- * on it - tough luck.
- */
-
-static int do_remount(struct nameidata *nd, int flags, int mnt_flags,
-		      void *data, xid_t xid)
-{
-	int err;
-	struct super_block * sb = nd->mnt->mnt_sb;
-
-	if (!capable(CAP_SYS_ADMIN) && !vx_ccaps(VXC_SECURE_REMOUNT))
-		return -EPERM;
-
-	if (!check_mnt(nd->mnt))
-		return -EINVAL;
-
-	if (nd->dentry != nd->mnt->mnt_root)
-		return -EINVAL;
-
-	if (vx_ccaps(VXC_SECURE_REMOUNT))
-		mnt_flags |= MNT_NODEV;
-	down_write(&sb->s_umount);
-	err = do_remount_sb(sb, flags, data, 0);
-	if (!err) {
-		nd->mnt->mnt_flags=mnt_flags;
-		if (flags & MS_XID)
-			nd->mnt->mnt_xid = xid;
-	}
-	up_write(&sb->s_umount);
-	if (!err)
-		security_sb_post_remount(nd->mnt, flags, data);
-	return err;
-}
-
-static int do_move_mount(struct nameidata *nd, char *old_name)
-{
-	struct nameidata old_nd, parent_nd;
-	struct vfsmount *p;
-	int err = 0;
-	if (!capable(CAP_SYS_ADMIN) && !vx_ccaps(VXC_SECURE_MOUNT))
-		return -EPERM;
-	if (!old_name || !*old_name)
-		return -EINVAL;
-	err = path_lookup(old_name, LOOKUP_FOLLOW, &old_nd);
-	if (err)
-		return err;
-
-	down_write(&current->namespace->sem);
-	while(d_mountpoint(nd->dentry) && follow_down(&nd->mnt, &nd->dentry))
-		;
-	err = -EINVAL;
-	if (!check_mnt(nd->mnt) || !check_mnt(old_nd.mnt))
-		goto out;
-
-	err = -ENOENT;
-	down(&nd->dentry->d_inode->i_sem);
-	if (IS_DEADDIR(nd->dentry->d_inode))
-		goto out1;
-
-	spin_lock(&vfsmount_lock);
-	if (!IS_ROOT(nd->dentry) && d_unhashed(nd->dentry))
-		goto out2;
-
-	err = -EINVAL;
-	if (old_nd.dentry != old_nd.mnt->mnt_root)
-		goto out2;
-
-	if (old_nd.mnt == old_nd.mnt->mnt_parent)
-		goto out2;
-
-	if (S_ISDIR(nd->dentry->d_inode->i_mode) !=
-	      S_ISDIR(old_nd.dentry->d_inode->i_mode))
-		goto out2;
-
-	err = -ELOOP;
-	for (p = nd->mnt; p->mnt_parent!=p; p = p->mnt_parent)
-		if (p == old_nd.mnt)
-			goto out2;
-	err = 0;
-
-	detach_mnt(old_nd.mnt, &parent_nd);
-	attach_mnt(old_nd.mnt, nd);
-
-	/* if the mount is moved, it should no longer be expire
-	 * automatically */
-	list_del_init(&old_nd.mnt->mnt_fslink);
-out2:
-	spin_unlock(&vfsmount_lock);
-out1:
-	up(&nd->dentry->d_inode->i_sem);
-out:
-	up_write(&current->namespace->sem);
-	if (!err)
-		path_release(&parent_nd);
-	path_release(&old_nd);
-	return err;
-}
-
-/*
- * create a new mount for userspace and request it to be added into the
- * namespace's tree
- */
-static int do_new_mount(struct nameidata *nd, char *type, int flags,
-			int mnt_flags, char *name, void *data)
-{
-	struct vfsmount *mnt;
-
-	if (!type || !memchr(type, 0, PAGE_SIZE))
-		return -EINVAL;
-
-	/* we need capabilities... */
-	if (!capable(CAP_SYS_ADMIN) && !vx_ccaps(VXC_SECURE_MOUNT))
-		return -EPERM;
-
-	mnt = do_kern_mount(type, flags, name, data);
-	if (IS_ERR(mnt))
-		return PTR_ERR(mnt);
-
-	return do_add_mount(mnt, nd, mnt_flags, NULL);
-}
-
-/*
- * add a mount into a namespace's mount tree
- * - provide the option of adding the new mount to an expiration list
- */
-int do_add_mount(struct vfsmount *newmnt, struct nameidata *nd,
-		 int mnt_flags, struct list_head *fslist)
-{
-	int err;
-
-	down_write(&current->namespace->sem);
-	/* Something was mounted here while we slept */
-	while(d_mountpoint(nd->dentry) && follow_down(&nd->mnt, &nd->dentry))
-		;
-	err = -EINVAL;
-	if (!check_mnt(nd->mnt))
-		goto unlock;
-
-	/* Refuse the same filesystem on the same mount point */
-	err = -EBUSY;
-	if (nd->mnt->mnt_sb == newmnt->mnt_sb &&
-	    nd->mnt->mnt_root == nd->dentry)
-		goto unlock;
-
-	err = -EINVAL;
-	if (S_ISLNK(newmnt->mnt_root->d_inode->i_mode))
-		goto unlock;
-
-	newmnt->mnt_flags = mnt_flags;
-	err = graft_tree(newmnt, nd);
-
-	if (err == 0 && fslist) {
-		/* add to the specified expiration list */
-		spin_lock(&vfsmount_lock);
-		list_add_tail(&newmnt->mnt_fslink, fslist);
-		spin_unlock(&vfsmount_lock);
-	}
-
-unlock:
-	up_write(&current->namespace->sem);
-	mntput(newmnt);
-	return err;
-}
-
-EXPORT_SYMBOL_GPL(do_add_mount);
-
-/*
- * process a list of expirable mountpoints with the intent of discarding any
- * mountpoints that aren't in use and haven't been touched since last we came
- * here
- */
-void mark_mounts_for_expiry(struct list_head *mounts)
-{
-	struct namespace *namespace;
-	struct vfsmount *mnt, *next;
-	LIST_HEAD(graveyard);
-
-	if (list_empty(mounts))
-		return;
-
-	spin_lock(&vfsmount_lock);
-
-	/* extract from the expiration list every vfsmount that matches the
-	 * following criteria:
-	 * - only referenced by its parent vfsmount
-	 * - still marked for expiry (marked on the last call here; marks are
-	 *   cleared by mntput())
-	 */
-	list_for_each_entry_safe(mnt, next, mounts, mnt_fslink) {
-		if (!xchg(&mnt->mnt_expiry_mark, 1) ||
-		    atomic_read(&mnt->mnt_count) != 1)
-			continue;
-
-		mntget(mnt);
-		list_move(&mnt->mnt_fslink, &graveyard);
-	}
-
-	/*
-	 * go through the vfsmounts we've just consigned to the graveyard to
-	 * - check that they're still dead
-	 * - delete the vfsmount from the appropriate namespace under lock
-	 * - dispose of the corpse
-	 */
-	while (!list_empty(&graveyard)) {
-		mnt = list_entry(graveyard.next, struct vfsmount, mnt_fslink);
-		list_del_init(&mnt->mnt_fslink);
-
-		/* don't do anything if the namespace is dead - all the
-		 * vfsmounts from it are going away anyway */
-		namespace = mnt->mnt_namespace;
-		if (!namespace || atomic_read(&namespace->count) <= 0)
-			continue;
-		get_namespace(namespace);
-
-		spin_unlock(&vfsmount_lock);
-		down_write(&namespace->sem);
-		spin_lock(&vfsmount_lock);
-
-		/* check that it is still dead: the count should now be 2 - as
-		 * contributed by the vfsmount parent and the mntget above */
-		if (atomic_read(&mnt->mnt_count) == 2) {
-			struct vfsmount *xdmnt;
-			struct dentry *xdentry;
-
-			/* delete from the namespace */
-			list_del_init(&mnt->mnt_list);
-			list_del_init(&mnt->mnt_child);
-			list_del_init(&mnt->mnt_hash);
-			mnt->mnt_mountpoint->d_mounted--;
-
-			xdentry = mnt->mnt_mountpoint;
-			mnt->mnt_mountpoint = mnt->mnt_root;
-			xdmnt = mnt->mnt_parent;
-			mnt->mnt_parent = mnt;
-
-			spin_unlock(&vfsmount_lock);
-
-			mntput(xdmnt);
-			dput(xdentry);
-
-			/* now lay it to rest if this was the last ref on the
-			 * superblock */
-			if (atomic_read(&mnt->mnt_sb->s_active) == 1) {
-				/* last instance - try to be smart */
-				lock_kernel();
-				DQUOT_OFF(mnt->mnt_sb);
-				acct_auto_close(mnt->mnt_sb);
-				unlock_kernel();
-			}
-
-			mntput(mnt);
-		} else {
-			/* someone brought it back to life whilst we didn't
-			 * have any locks held so return it to the expiration
-			 * list */
-			list_add_tail(&mnt->mnt_fslink, mounts);
-			spin_unlock(&vfsmount_lock);
-		}
-
-		up_write(&namespace->sem);
-
-		mntput(mnt);
-		put_namespace(namespace);
-
-		spin_lock(&vfsmount_lock);
-	}
-
-	spin_unlock(&vfsmount_lock);
-}
-
-EXPORT_SYMBOL_GPL(mark_mounts_for_expiry);
-
-/*
- * Some copy_from_user() implementations do not return the exact number of
- * bytes remaining to copy on a fault.  But copy_mount_options() requires that.
- * Note that this function differs from copy_from_user() in that it will oops
- * on bad values of `to', rather than returning a short copy.
- */
-static long
-exact_copy_from_user(void *to, const void __user *from, unsigned long n)
-{
-	char *t = to;
-	const char __user *f = from;
-	char c;
-
-	if (!access_ok(VERIFY_READ, from, n))
-		return n;
-
-	while (n) {
-		if (__get_user(c, f)) {
-			memset(t, 0, n);
-			break;
-		}
-		*t++ = c;
-		f++;
-		n--;
-	}
-	return n;
-}
-
-int copy_mount_options(const void __user *data, unsigned long *where)
-{
-	int i;
-	unsigned long page;
-	unsigned long size;
-	
-	*where = 0;
-	if (!data)
-		return 0;
-
-	if (!(page = __get_free_page(GFP_KERNEL)))
-		return -ENOMEM;
-
-	/* We only care that *some* data at the address the user
-	 * gave us is valid.  Just in case, we'll zero
-	 * the remainder of the page.
-	 */
-	/* copy_from_user cannot cross TASK_SIZE ! */
-	size = TASK_SIZE - (unsigned long)data;
-	if (size > PAGE_SIZE)
-		size = PAGE_SIZE;
-
-	i = size - exact_copy_from_user((void *)page, data, size);
-	if (!i) {
-		free_page(page); 
-		return -EFAULT;
-	}
-	if (i != PAGE_SIZE)
-		memset((char *)page + i, 0, PAGE_SIZE - i);
-	*where = page;
-	return 0;
-}
-
-/*
- * Flags is a 32-bit value that allows up to 31 non-fs dependent flags to
- * be given to the mount() call (ie: read-only, no-dev, no-suid etc).
- *
- * data is a (void *) that can point to any structure up to
- * PAGE_SIZE-1 bytes, which can contain arbitrary fs-dependent
- * information (or be NULL).
- *
- * Pre-0.97 versions of mount() didn't have a flags word.
- * When the flags word was introduced its top half was required
- * to have the magic value 0xC0ED, and this remained so until 2.4.0-test9.
- * Therefore, if this magic number is present, it carries no information
- * and must be discarded.
- */
-long do_mount(char * dev_name, char * dir_name, char *type_page,
-		  unsigned long flags, void *data_page)
-{
-	struct nameidata nd;
-	int retval = 0;
-	int mnt_flags = 0;
-	xid_t xid = 0;
-
-	/* Discard magic */
-	if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
-		flags &= ~MS_MGC_MSK;
-
-	/* Basic sanity checks */
-
-	if (!dir_name || !*dir_name || !memchr(dir_name, 0, PAGE_SIZE))
-		return -EINVAL;
-	if (dev_name && !memchr(dev_name, 0, PAGE_SIZE))
-		return -EINVAL;
-
-	if (data_page)
-		((char *)data_page)[PAGE_SIZE - 1] = 0;
-
-	retval = vx_parse_xid(data_page, &xid, 1);
-	if (retval) {
-		mnt_flags |= MNT_XID;
-		/* bind and re-mounts get xid flag */
-		if (flags & (MS_BIND|MS_REMOUNT))
-			flags |= MS_XID;
-	}
-
-	/* Separate the per-mountpoint flags */
-	if (flags & MS_NOSUID)
-		mnt_flags |= MNT_NOSUID;
-	if (flags & MS_NODEV)
-		mnt_flags |= MNT_NODEV;
-	if (flags & MS_NOEXEC)
-		mnt_flags |= MNT_NOEXEC;
-	flags &= ~(MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_ACTIVE);
-
-	if (vx_ccaps(VXC_SECURE_MOUNT))
-		mnt_flags |= MNT_NODEV;
-
-	/* ... and get the mountpoint */
-	retval = path_lookup(dir_name, LOOKUP_FOLLOW, &nd);
-	if (retval)
-		return retval;
-
-	retval = security_sb_mount(dev_name, &nd, type_page, flags, data_page);
-	if (retval)
-		goto dput_out;
-
-	if (flags & MS_REMOUNT)
-		retval = do_remount(&nd, flags & ~MS_REMOUNT, mnt_flags,
-				    data_page, xid);
-	else if (flags & MS_BIND)
-		retval = do_loopback(&nd, dev_name, xid, flags);
-	else if (flags & MS_MOVE)
-		retval = do_move_mount(&nd, dev_name);
-	else
-		retval = do_new_mount(&nd, type_page, flags, mnt_flags,
-				      dev_name, data_page);
-dput_out:
-	path_release(&nd);
-	return retval;
-}
-
-int copy_namespace(int flags, struct task_struct *tsk)
-{
-	struct namespace *namespace = tsk->namespace;
-	struct namespace *new_ns;
-	struct vfsmount *rootmnt = NULL, *pwdmnt = NULL, *altrootmnt = NULL;
-	struct fs_struct *fs = tsk->fs;
-	struct vfsmount *p, *q;
-
-	if (!namespace)
-		return 0;
-
-	get_namespace(namespace);
-
-	if (!(flags & CLONE_NEWNS))
-		return 0;
-
-	if (!capable(CAP_SYS_ADMIN) && !vx_ccaps(VXC_SECURE_MOUNT)) {
-		put_namespace(namespace);
-		return -EPERM;
-	}
-
-	new_ns = kmalloc(sizeof(struct namespace), GFP_KERNEL);
-	if (!new_ns)
-		goto out;
-
-	atomic_set(&new_ns->count, 1);
-	init_rwsem(&new_ns->sem);
-	INIT_LIST_HEAD(&new_ns->list);
-
-	down_write(&tsk->namespace->sem);
-	/* First pass: copy the tree topology */
-	new_ns->root = copy_tree(namespace->root, namespace->root->mnt_root);
-	if (!new_ns->root) {
-		up_write(&tsk->namespace->sem);
-		kfree(new_ns);
-		goto out;
-	}
-	spin_lock(&vfsmount_lock);
-	list_add_tail(&new_ns->list, &new_ns->root->mnt_list);
-	spin_unlock(&vfsmount_lock);
-
-	/*
-	 * Second pass: switch the tsk->fs->* elements and mark new vfsmounts
-	 * as belonging to new namespace.  We have already acquired a private
-	 * fs_struct, so tsk->fs->lock is not needed.
-	 */
-	p = namespace->root;
-	q = new_ns->root;
-	while (p) {
-		q->mnt_namespace = new_ns;
-		if (fs) {
-			if (p == fs->rootmnt) {
-				rootmnt = p;
-				fs->rootmnt = mntget(q);
-			}
-			if (p == fs->pwdmnt) {
-				pwdmnt = p;
-				fs->pwdmnt = mntget(q);
-			}
-			if (p == fs->altrootmnt) {
-				altrootmnt = p;
-				fs->altrootmnt = mntget(q);
-			}
-		}
-		p = next_mnt(p, namespace->root);
-		q = next_mnt(q, new_ns->root);
-	}
-	up_write(&tsk->namespace->sem);
-
-	tsk->namespace = new_ns;
-
-	if (rootmnt)
-		mntput(rootmnt);
-	if (pwdmnt)
-		mntput(pwdmnt);
-	if (altrootmnt)
-		mntput(altrootmnt);
-
-	put_namespace(namespace);
-	return 0;
-
-out:
-	put_namespace(namespace);
-	return -ENOMEM;
-}
-
-asmlinkage long sys_mount(char __user * dev_name, char __user * dir_name,
-			  char __user * type, unsigned long flags,
-			  void __user * data)
-{
-	int retval;
-	unsigned long data_page;
-	unsigned long type_page;
-	unsigned long dev_page;
-	char *dir_page;
-
-	retval = copy_mount_options (type, &type_page);
-	if (retval < 0)
-		return retval;
-
-	dir_page = getname(dir_name);
-	retval = PTR_ERR(dir_page);
-	if (IS_ERR(dir_page))
-		goto out1;
-
-	retval = copy_mount_options (dev_name, &dev_page);
-	if (retval < 0)
-		goto out2;
-
-	retval = copy_mount_options (data, &data_page);
-	if (retval < 0)
-		goto out3;
-
-	lock_kernel();
-	retval = do_mount((char*)dev_page, dir_page, (char*)type_page,
-			  flags, (void*)data_page);
-	unlock_kernel();
-	free_page(data_page);
-
-out3:
-	free_page(dev_page);
-out2:
-	putname(dir_page);
-out1:
-	free_page(type_page);
-	return retval;
-}
-
-/*
- * Replace the fs->{rootmnt,root} with {mnt,dentry}. Put the old values.
- * It can block. Requires the big lock held.
- */
-void set_fs_root(struct fs_struct *fs, struct vfsmount *mnt,
-		 struct dentry *dentry)
-{
-	struct dentry *old_root;
-	struct vfsmount *old_rootmnt;
-	write_lock(&fs->lock);
-	old_root = fs->root;
-	old_rootmnt = fs->rootmnt;
-	fs->rootmnt = mntget(mnt);
-	fs->root = dget(dentry);
-	write_unlock(&fs->lock);
-	if (old_root) {
-		dput(old_root);
-		mntput(old_rootmnt);
-	}
-}
-
-/*
- * Replace the fs->{pwdmnt,pwd} with {mnt,dentry}. Put the old values.
- * It can block. Requires the big lock held.
- */
-void set_fs_pwd(struct fs_struct *fs, struct vfsmount *mnt,
-		struct dentry *dentry)
-{
-	struct dentry *old_pwd;
-	struct vfsmount *old_pwdmnt;
-
-	write_lock(&fs->lock);
-	old_pwd = fs->pwd;
-	old_pwdmnt = fs->pwdmnt;
-	fs->pwdmnt = mntget(mnt);
-	fs->pwd = dget(dentry);
-	write_unlock(&fs->lock);
-
-	if (old_pwd) {
-		dput(old_pwd);
-		mntput(old_pwdmnt);
-	}
-}
-
-static void chroot_fs_refs(struct nameidata *old_nd, struct nameidata *new_nd)
-{
-	struct task_struct *g, *p;
-	struct fs_struct *fs;
-
-	read_lock(&tasklist_lock);
-	do_each_thread(g, p) {
-		task_lock(p);
-		fs = p->fs;
-		if (fs) {
-			atomic_inc(&fs->count);
-			task_unlock(p);
-			if (fs->root==old_nd->dentry&&fs->rootmnt==old_nd->mnt)
-				set_fs_root(fs, new_nd->mnt, new_nd->dentry);
-			if (fs->pwd==old_nd->dentry&&fs->pwdmnt==old_nd->mnt)
-				set_fs_pwd(fs, new_nd->mnt, new_nd->dentry);
-			put_fs_struct(fs);
-		} else
-			task_unlock(p);
-	} while_each_thread(g, p);
-	read_unlock(&tasklist_lock);
-}
-
-/*
- * Moves the current root to put_root, and sets root/cwd of all processes
- * which had them on the old root to new_root.
- *
- * Note:
- *  - we don't move root/cwd if they are not at the root (reason: if something
- *    cared enough to change them, it's probably wrong to force them elsewhere)
- *  - it's okay to pick a root that isn't the root of a file system, e.g.
- *    /nfs/my_root where /nfs is the mount point. It must be a mountpoint,
- *    though, so you may need to say mount --bind /nfs/my_root /nfs/my_root
- *    first.
- */
-
-asmlinkage long sys_pivot_root(const char __user *new_root, const char __user *put_old)
-{
-	struct vfsmount *tmp;
-	struct nameidata new_nd, old_nd, parent_nd, root_parent, user_nd;
-	int error;
-
-	if (!capable(CAP_SYS_ADMIN))
-		return -EPERM;
-
-	lock_kernel();
-
-	error = __user_walk(new_root, LOOKUP_FOLLOW|LOOKUP_DIRECTORY, &new_nd);
-	if (error)
-		goto out0;
-	error = -EINVAL;
-	if (!check_mnt(new_nd.mnt))
-		goto out1;
-
-	error = __user_walk(put_old, LOOKUP_FOLLOW|LOOKUP_DIRECTORY, &old_nd);
-	if (error)
-		goto out1;
-
-	error = security_sb_pivotroot(&old_nd, &new_nd);
-	if (error) {
-		path_release(&old_nd);
-		goto out1;
-	}
-
-	read_lock(&current->fs->lock);
-	user_nd.mnt = mntget(current->fs->rootmnt);
-	user_nd.dentry = dget(current->fs->root);
-	read_unlock(&current->fs->lock);
-	down_write(&current->namespace->sem);
-	down(&old_nd.dentry->d_inode->i_sem);
-	error = -EINVAL;
-	if (!check_mnt(user_nd.mnt))
-		goto out2;
-	error = -ENOENT;
-	if (IS_DEADDIR(new_nd.dentry->d_inode))
-		goto out2;
-	if (d_unhashed(new_nd.dentry) && !IS_ROOT(new_nd.dentry))
-		goto out2;
-	if (d_unhashed(old_nd.dentry) && !IS_ROOT(old_nd.dentry))
-		goto out2;
-	error = -EBUSY;
-	if (new_nd.mnt == user_nd.mnt || old_nd.mnt == user_nd.mnt)
-		goto out2; /* loop */
-	error = -EINVAL;
-	if (user_nd.mnt->mnt_root != user_nd.dentry)
-		goto out2;
-	if (new_nd.mnt->mnt_root != new_nd.dentry)
-		goto out2; /* not a mountpoint */
-	tmp = old_nd.mnt; /* make sure we can reach put_old from new_root */
-	spin_lock(&vfsmount_lock);
-	if (tmp != new_nd.mnt) {
-		for (;;) {
-			if (tmp->mnt_parent == tmp)
-				goto out3;
-			if (tmp->mnt_parent == new_nd.mnt)
-				break;
-			tmp = tmp->mnt_parent;
-		}
-		if (!is_subdir(tmp->mnt_mountpoint, new_nd.dentry))
-			goto out3;
-	} else if (!is_subdir(old_nd.dentry, new_nd.dentry))
-		goto out3;
-	detach_mnt(new_nd.mnt, &parent_nd);
-	detach_mnt(user_nd.mnt, &root_parent);
-	attach_mnt(user_nd.mnt, &old_nd);
-	attach_mnt(new_nd.mnt, &root_parent);
-	spin_unlock(&vfsmount_lock);
-	chroot_fs_refs(&user_nd, &new_nd);
-	security_sb_post_pivotroot(&user_nd, &new_nd);
-	error = 0;
-	path_release(&root_parent);
-	path_release(&parent_nd);
-out2:
-	up(&old_nd.dentry->d_inode->i_sem);
-	up_write(&current->namespace->sem);
-	path_release(&user_nd);
-	path_release(&old_nd);
-out1:
-	path_release(&new_nd);
-out0:
-	unlock_kernel();
-	return error;
-out3:
-	spin_unlock(&vfsmount_lock);
-	goto out2;
-}
-
-static void __init init_mount_tree(void)
-{
-	struct vfsmount *mnt;
-	struct namespace *namespace;
-	struct task_struct *g, *p;
-
-	mnt = do_kern_mount("rootfs", 0, "rootfs", NULL);
-	if (IS_ERR(mnt))
-		panic("Can't create rootfs");
-	namespace = kmalloc(sizeof(*namespace), GFP_KERNEL);
-	if (!namespace)
-		panic("Can't allocate initial namespace");
-	atomic_set(&namespace->count, 1);
-	INIT_LIST_HEAD(&namespace->list);
-	init_rwsem(&namespace->sem);
-	list_add(&mnt->mnt_list, &namespace->list);
-	namespace->root = mnt;
-	mnt->mnt_namespace = namespace;
-
-	init_task.namespace = namespace;
-	read_lock(&tasklist_lock);
-	do_each_thread(g, p) {
-		get_namespace(namespace);
-		p->namespace = namespace;
-	} while_each_thread(g, p);
-	read_unlock(&tasklist_lock);
-
-	set_fs_pwd(current->fs, namespace->root, namespace->root->mnt_root);
-	set_fs_root(current->fs, namespace->root, namespace->root->mnt_root);
-}
-
-void __init mnt_init(unsigned long mempages)
-{
-	struct list_head *d;
-	unsigned long order;
-	unsigned int nr_hash;
-	int i;
-
-	mnt_cache = kmem_cache_create("mnt_cache", sizeof(struct vfsmount),
-			0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
-
-	order = 0; 
-	mount_hashtable = (struct list_head *)
-		__get_free_pages(GFP_ATOMIC, order);
-
-	if (!mount_hashtable)
-		panic("Failed to allocate mount hash table\n");
-
-	/*
-	 * Find the power-of-two list-heads that can fit into the allocation..
-	 * We don't guarantee that "sizeof(struct list_head)" is necessarily
-	 * a power-of-two.
-	 */
-	nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct list_head);
-	hash_bits = 0;
-	do {
-		hash_bits++;
-	} while ((nr_hash >> hash_bits) != 0);
-	hash_bits--;
-
-	/*
-	 * Re-calculate the actual number of entries and the mask
-	 * from the number of bits we can fit.
-	 */
-	nr_hash = 1UL << hash_bits;
-	hash_mask = nr_hash-1;
-
-	printk("Mount-cache hash table entries: %d (order: %ld, %ld bytes)\n",
-			nr_hash, order, (PAGE_SIZE << order));
-
-	/* And initialize the newly allocated array */
-	d = mount_hashtable;
-	i = nr_hash;
-	do {
-		INIT_LIST_HEAD(d);
-		d++;
-		i--;
-	} while (i);
-	sysfs_init();
-	init_rootfs();
-	init_mount_tree();
-}
-
-void __put_namespace(struct namespace *namespace)
-{
-	struct vfsmount *mnt;
-
-	down_write(&namespace->sem);
-	spin_lock(&vfsmount_lock);
-
-	list_for_each_entry(mnt, &namespace->list, mnt_list) {
-		mnt->mnt_namespace = NULL;
-	}
-
-	umount_tree(namespace->root);
-	spin_unlock(&vfsmount_lock);
-	up_write(&namespace->sem);
-	kfree(namespace);
-}
-- 
2.47.0