patch-2.4.11-dontuse linux/fs/super.c

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diff -u --recursive --new-file v2.4.10/linux/fs/super.c linux/fs/super.c
@@ -42,19 +42,11 @@
 #define __NO_VERSION__
 #include <linux/module.h>
 
-/*
- * We use a semaphore to synchronize all mount/umount
- * activity - imagine the mess if we have a race between
- * unmounting a filesystem and re-mounting it (or something
- * else).
- */
-static DECLARE_MUTEX(mount_sem);
-
 extern void wait_for_keypress(void);
 
 extern int root_mountflags;
 
-static int do_remount_sb(struct super_block *sb, int flags, char * data);
+int do_remount_sb(struct super_block *sb, int flags, void * data);
 
 /* this is initialized in init/main.c */
 kdev_t ROOT_DEV;
@@ -279,371 +271,13 @@
 	return fs;
 }
 
-static LIST_HEAD(vfsmntlist);
-
-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(void)
-{
-	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);
-		mnt->mnt_owner = current->uid;
-	}
-	return mnt;
-}
-
-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;
-
-	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)
-			break;
-	}
-	return p;
-}
-
-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(&mnt->mnt_child, &nd->mnt->mnt_mounts);
-	nd->dentry->d_mounted++;
-}
-
-/**
- *	add_vfsmnt - add a new mount node
- *	@nd: location of mountpoint or %NULL if we want a root node
- *	@root: root of (sub)tree to be mounted
- *	@dev_name: device name to show in /proc/mounts or %NULL (for "none").
- *
- *	This is VFS idea of mount. New node is allocated, bound to a tree
- *	we are mounting and optionally (OK, usually) registered as mounted
- *	on a given mountpoint. Returns a pointer to new node or %NULL in
- *	case of failure.
- *
- *	Potential reason for failure (aside of trivial lack of memory) is a
- *	deleted mountpoint. Caller must hold ->i_zombie on mountpoint
- *	dentry (if any).
- */
-
-static struct vfsmount *add_vfsmnt(struct dentry *root, const char *dev_name)
-{
-	struct vfsmount *mnt;
-	struct super_block *sb = root->d_inode->i_sb;
-	char *name;
-
-	mnt = alloc_vfsmnt();
-	if (!mnt)
-		goto out;
-
-	/* It may be NULL, but who cares? */
-	if (dev_name) {
-		name = kmalloc(strlen(dev_name)+1, GFP_KERNEL);
-		if (name) {
-			strcpy(name, dev_name);
-			mnt->mnt_devname = name;
-		}
-	}
-	mnt->mnt_sb = sb;
-	mnt->mnt_root = dget(root);
-	mnt->mnt_mountpoint = mnt->mnt_root;
-	mnt->mnt_parent = mnt;
-
-	spin_lock(&dcache_lock);
-	list_add(&mnt->mnt_list, vfsmntlist.prev);
-	spin_unlock(&dcache_lock);
-out:
-	return mnt;
-}
-
-static struct vfsmount *clone_mnt(struct vfsmount *old, struct dentry *root)
-{
-	char *name = old->mnt_devname;
-	struct vfsmount *mnt = alloc_vfsmnt();
-	struct super_block *sb = old->mnt_sb;
-
-	if (!mnt)
-		goto out;
-
-	if (name) {
-		mnt->mnt_devname = kmalloc(strlen(name)+1, GFP_KERNEL);
-		if (mnt->mnt_devname)
-			strcpy(mnt->mnt_devname, name);
-	}
-	mnt->mnt_sb = sb;
-	mnt->mnt_root = dget(root);
-	mnt->mnt_mountpoint = mnt->mnt_root;
-	mnt->mnt_parent = mnt;
-	mnt->mnt_flags = old->mnt_flags;
-
-	atomic_inc(&sb->s_active);
-out:
-	return mnt;
-}
-
-static int graft_tree(struct vfsmount *mnt, struct nameidata *nd)
-{
-	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;
-
-	down(&nd->dentry->d_inode->i_zombie);
-	if (IS_DEADDIR(nd->dentry->d_inode))
-		goto fail1;
-
-	spin_lock(&dcache_lock);
-	if (!IS_ROOT(nd->dentry) && d_unhashed(nd->dentry))
-		goto fail;
-
-	attach_mnt(mnt, nd);
-	list_add(&mnt->mnt_list, vfsmntlist.prev);
-	spin_unlock(&dcache_lock);
-	up(&nd->dentry->d_inode->i_zombie);
-	mntget(mnt);
-	return 0;
-fail:
-	spin_unlock(&dcache_lock);
-fail1:
-	up(&nd->dentry->d_inode->i_zombie);
-	return -ENOENT;
-}
-
-#ifdef CONFIG_BLK_DEV_INITRD
-static void move_vfsmnt(struct vfsmount *mnt,
-			struct nameidata *nd, 
-			const char *dev_name)
-{
-	struct nameidata parent_nd;
-	char *new_devname = NULL;
-
-	if (dev_name) {
-		new_devname = kmalloc(strlen(dev_name)+1, GFP_KERNEL);
-		if (new_devname)
-			strcpy(new_devname, dev_name);
-	}
-
-	spin_lock(&dcache_lock);
-	detach_mnt(mnt, &parent_nd);
-	attach_mnt(mnt, nd);
-
-	if (new_devname) {
-		if (mnt->mnt_devname)
-			kfree(mnt->mnt_devname);
-		mnt->mnt_devname = new_devname;
-	}
-	spin_unlock(&dcache_lock);
-
-	/* put the old stuff */
-	if (parent_nd.mnt != mnt)
-		path_release(&parent_nd);
-}
-#endif
-
-static void kill_super(struct super_block *);
-
-void __mntput(struct vfsmount *mnt)
-{
-	struct super_block *sb = mnt->mnt_sb;
-
-	dput(mnt->mnt_root);
-	if (mnt->mnt_devname)
-		kfree(mnt->mnt_devname);
-	kmem_cache_free(mnt_cache, mnt);
-	kill_super(sb);
-}
-
-/* Use octal escapes, like mount does, for embedded spaces etc. */
-static unsigned char need_escaping[] = { ' ', '\t', '\n', '\\' };
-
-static int
-mangle(const unsigned char *s, char *buf, int len) {
-        char *sp;
-        int n;
-
-        sp = buf;
-        while(*s && sp-buf < len-3) {
-                for (n = 0; n < sizeof(need_escaping); n++) {
-                        if (*s == need_escaping[n]) {
-                                *sp++ = '\\';
-                                *sp++ = '0' + ((*s & 0300) >> 6);
-                                *sp++ = '0' + ((*s & 070) >> 3);
-                                *sp++ = '0' + (*s & 07);
-                                goto next;
-                        }
-                }
-                *sp++ = *s;
-        next:
-                s++;
-        }
-        return sp - buf;	/* no trailing NUL */
-}
-
-static struct proc_fs_info {
-	int flag;
-	char *str;
-} fs_info[] = {
-	{ MS_SYNCHRONOUS, ",sync" },
-	{ MS_MANDLOCK, ",mand" },
-	{ MS_NOATIME, ",noatime" },
-	{ MS_NODIRATIME, ",nodiratime" },
-	{ 0, NULL }
-};
-
-static struct proc_fs_info mnt_info[] = {
-	{ MNT_NOSUID, ",nosuid" },
-	{ MNT_NODEV, ",nodev" },
-	{ MNT_NOEXEC, ",noexec" },
-	{ 0, NULL }
-};
-
-static struct proc_nfs_info {
-	int flag;
-	char *str;
-	char *nostr;
-} nfs_info[] = {
-	{ NFS_MOUNT_SOFT, ",soft", ",hard" },
-	{ NFS_MOUNT_INTR, ",intr", "" },
-	{ NFS_MOUNT_POSIX, ",posix", "" },
-	{ NFS_MOUNT_TCP, ",tcp", ",udp" },
-	{ NFS_MOUNT_NOCTO, ",nocto", "" },
-	{ NFS_MOUNT_NOAC, ",noac", "" },
-	{ NFS_MOUNT_NONLM, ",nolock", ",lock" },
-	{ NFS_MOUNT_BROKEN_SUID, ",broken_suid", "" },
-	{ 0, NULL, NULL }
-};
-
-int get_filesystem_info( char *buf )
-{
-	struct list_head *p;
-	struct proc_fs_info *fs_infop;
-	struct proc_nfs_info *nfs_infop;
-	struct nfs_server *nfss;
-	int len, prevlen;
-	char *path, *buffer = (char *) __get_free_page(GFP_KERNEL);
-
-	if (!buffer) return 0;
-	len = prevlen = 0;
-
-#define FREEROOM	((int)PAGE_SIZE-200-len)
-#define MANGLE(s)	len += mangle((s), buf+len, FREEROOM);
-
-	for (p = vfsmntlist.next; p != &vfsmntlist; p = p->next) {
-		struct vfsmount *tmp = list_entry(p, struct vfsmount, mnt_list);
-		path = d_path(tmp->mnt_root, tmp, buffer, PAGE_SIZE);
-		if (!path)
-			continue;
-		MANGLE(tmp->mnt_devname ? tmp->mnt_devname : "none");
-		buf[len++] = ' ';
-		MANGLE(path);
-		buf[len++] = ' ';
-		MANGLE(tmp->mnt_sb->s_type->name);
-		len += sprintf(buf+len, " %s",
-			       tmp->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
-		for (fs_infop = fs_info; fs_infop->flag; fs_infop++) {
-			if (tmp->mnt_sb->s_flags & fs_infop->flag)
-				MANGLE(fs_infop->str);
-		}
-		for (fs_infop = mnt_info; fs_infop->flag; fs_infop++) {
-			if (tmp->mnt_flags & fs_infop->flag)
-				MANGLE(fs_infop->str);
-		}
-		if (!strcmp("nfs", tmp->mnt_sb->s_type->name)) {
-			nfss = &tmp->mnt_sb->u.nfs_sb.s_server;
-			len += sprintf(buf+len, ",v%d", nfss->rpc_ops->version);
-
-			len += sprintf(buf+len, ",rsize=%d", nfss->rsize);
-
-			len += sprintf(buf+len, ",wsize=%d", nfss->wsize);
-#if 0
-			if (nfss->timeo != 7*HZ/10) {
-				len += sprintf(buf+len, ",timeo=%d",
-					       nfss->timeo*10/HZ);
-			}
-			if (nfss->retrans != 3) {
-				len += sprintf(buf+len, ",retrans=%d",
-					       nfss->retrans);
-			}
-#endif
-			if (nfss->acregmin != 3*HZ) {
-				len += sprintf(buf+len, ",acregmin=%d",
-					       nfss->acregmin/HZ);
-			}
-			if (nfss->acregmax != 60*HZ) {
-				len += sprintf(buf+len, ",acregmax=%d",
-					       nfss->acregmax/HZ);
-			}
-			if (nfss->acdirmin != 30*HZ) {
-				len += sprintf(buf+len, ",acdirmin=%d",
-					       nfss->acdirmin/HZ);
-			}
-			if (nfss->acdirmax != 60*HZ) {
-				len += sprintf(buf+len, ",acdirmax=%d",
-					       nfss->acdirmax/HZ);
-			}
-			for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
-				char *str;
-				if (nfss->flags & nfs_infop->flag)
-					str = nfs_infop->str;
-				else
-					str = nfs_infop->nostr;
-				MANGLE(str);
-			}
-			len += sprintf(buf+len, ",addr=");
-			MANGLE(nfss->hostname);
-		}
-		len += sprintf(buf + len, " 0 0\n");
-		if (FREEROOM <= 3) {
-			len = prevlen;
-			len += sprintf(buf+len, "# truncated\n");
-			break;
-		}
-		prevlen = len;
-	}
-
-	free_page((unsigned long) buffer);
-	return len;
-#undef MANGLE
-#undef FREEROOM
-}
+struct vfsmount *alloc_vfsmnt(void);
+void free_vfsmnt(struct vfsmount *mnt);
+void set_devname(struct vfsmount *mnt, const char *name);
+
+/* Will go away */
+extern struct vfsmount *root_vfsmnt;
+extern int graft_tree(struct vfsmount *mnt, struct nameidata *nd);
 
 static inline void __put_super(struct super_block *sb)
 {
@@ -759,9 +393,7 @@
         struct statfs sbuf;
 	int err = -EINVAL;
 
-	lock_kernel();
         s = get_super(to_kdev_t(dev));
-	unlock_kernel();
         if (s == NULL)
                 goto out;
 	err = vfs_statfs(s, &sbuf);
@@ -1082,7 +714,7 @@
 	}
 }
 
-static void kill_super(struct super_block *sb)
+void kill_super(struct super_block *sb)
 {
 	struct block_device *bdev;
 	kdev_t dev;
@@ -1144,7 +776,7 @@
  * is used as a reference - file system type and the device are ignored.
  */
 
-static int do_remount_sb(struct super_block *sb, int flags, char *data)
+int do_remount_sb(struct super_block *sb, int flags, void *data)
 {
 	int retval;
 	
@@ -1177,234 +809,6 @@
 	return 0;
 }
 
-/*
- * 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;
-}
-
-static int do_umount(struct vfsmount *mnt, int flags)
-{
-	struct super_block * sb = mnt->mnt_sb;
-	struct nameidata parent_nd;
-
-	/*
-	 * 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.
-	 * The problem being: we have to implement rootfs and GC for that ;-)
-	 * 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) {
-		int retval = 0;
-		/*
-		 * Special case for "unmounting" root ...
-		 * we just try to remount it readonly.
-		 */
-		if (!(sb->s_flags & MS_RDONLY)) {
-			down_write(&sb->s_umount);
-			retval = do_remount_sb(sb, MS_RDONLY, 0);
-			up_write(&sb->s_umount);
-		}
-		return retval;
-	}
-
-	spin_lock(&dcache_lock);
-
-	if (atomic_read(&sb->s_active) > 1) {
-		if (atomic_read(&mnt->mnt_count) > 2) {
-			spin_unlock(&dcache_lock);
-			return -EBUSY;
-		}
-		detach_mnt(mnt, &parent_nd);
-		list_del(&mnt->mnt_list);
-		spin_unlock(&dcache_lock);
-		mntput(mnt);
-		if (parent_nd.mnt != mnt)
-			path_release(&parent_nd);
-		return 0;
-	}
-	spin_unlock(&dcache_lock);
-
-	/*
-	 * Before checking whether the filesystem is still busy,
-	 * make sure the kernel doesn't hold any quota files open
-	 * on the device. If the umount fails, too bad -- there
-	 * are no quotas running any more. Just turn them on again.
-	 */
-	DQUOT_OFF(sb);
-	acct_auto_close(sb->s_dev);
-
-	/*
-	 * 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.
-	 */
-
-	if( (flags&MNT_FORCE) && sb->s_op->umount_begin)
-		sb->s_op->umount_begin(sb);
-
-	/* Something might grab it again - redo checks */
-
-	spin_lock(&dcache_lock);
-	if (atomic_read(&mnt->mnt_count) > 2) {
-		spin_unlock(&dcache_lock);
-		return -EBUSY;
-	}
-
-	/* OK, that's the point of no return */
-	detach_mnt(mnt, &parent_nd);
-	list_del(&mnt->mnt_list);
-	spin_unlock(&dcache_lock);
-	mntput(mnt);
-	if (parent_nd.mnt != mnt)
-		path_release(&parent_nd);
-	return 0;
-}
-
-/*
- * 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 * name, int flags)
-{
-	struct nameidata nd;
-	char *kname;
-	int retval;
-
-	kname = getname(name);
-	retval = PTR_ERR(kname);
-	if (IS_ERR(kname))
-		goto out;
-	retval = 0;
-	if (path_init(kname, LOOKUP_POSITIVE|LOOKUP_FOLLOW, &nd))
-		retval = path_walk(kname, &nd);
-	putname(kname);
-	if (retval)
-		goto out;
-	retval = -EINVAL;
-	if (nd.dentry != nd.mnt->mnt_root)
-		goto dput_and_out;
-
-	retval = -EPERM;
-	if (!capable(CAP_SYS_ADMIN) && current->uid!=nd.mnt->mnt_owner)
-		goto dput_and_out;
-
-	down(&mount_sem);
-	lock_kernel();
-	retval = do_umount(nd.mnt, flags);
-	unlock_kernel();
-	path_release(&nd);
-	up(&mount_sem);
-	goto out;
-dput_and_out:
-	path_release(&nd);
-out:
-	return retval;
-}
-
-/*
- *	The 2.0 compatible umount. No flags. 
- */
- 
-asmlinkage long sys_oldumount(char * name)
-{
-	return sys_umount(name,0);
-}
-
-static int mount_is_safe(struct nameidata *nd)
-{
-	if (capable(CAP_SYS_ADMIN))
-		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))
-		return -EPERM;
-	return 0;
-#endif
-}
-
-/*
- * do loopback mount.
- */
-static int do_loopback(struct nameidata *nd, char *old_name)
-{
-	struct nameidata old_nd;
-	struct vfsmount *mnt;
-	int err;
-
-	err = mount_is_safe(nd);
-	if (err)
-		return err;
-
-	if (!old_name || !*old_name)
-		return -EINVAL;
-
-	if (path_init(old_name, LOOKUP_POSITIVE|LOOKUP_FOLLOW, &old_nd))
-		err = path_walk(old_name, &old_nd);
-	if (err)
-		return err;
-
-	down(&mount_sem);
-	err = -ENOMEM;
-	mnt = clone_mnt(old_nd.mnt, old_nd.dentry);
-	if (mnt) {
-		err = graft_tree(mnt, nd);
-		mntput(mnt);
-	}
-	up(&mount_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,char *data)
-{
-	int err;
-	struct super_block * sb = nd->mnt->mnt_sb;
-
-	if (!capable(CAP_SYS_ADMIN))
-		return -EPERM;
-
-	if (nd->dentry != nd->mnt->mnt_root)
-		return -EINVAL;
-
-	down_write(&sb->s_umount);
-	err = do_remount_sb(sb, flags, data);
-	if (!err)
-		nd->mnt->mnt_flags=mnt_flags;
-	up_write(&sb->s_umount);
-	return err;
-}
-
 struct vfsmount *do_kern_mount(char *type, int flags, char *name, void *data)
 {
 	struct file_system_type * fstype;
@@ -1429,12 +833,7 @@
 		mnt = ERR_PTR(-ENOMEM);
 		goto fs_out;
 	}
-	if (name) {
-		mnt->mnt_devname = kmalloc(strlen(name)+1, GFP_KERNEL);
-		if (mnt->mnt_devname)
-			strcpy(mnt->mnt_devname, name);
-	}
-
+	set_devname(mnt, name);
 	/* get locked superblock */
 	if (fstype->fs_flags & FS_REQUIRES_DEV)
 		sb = get_sb_bdev(fstype, name, flags, data);
@@ -1444,9 +843,7 @@
 		sb = get_sb_nodev(fstype, flags, data);
 
 	if (IS_ERR(sb)) {
-		if (mnt->mnt_devname)
-			kfree(mnt->mnt_devname);
-		kmem_cache_free(mnt_cache, mnt);
+		free_vfsmnt(mnt);
 		mnt = (struct vfsmount *)sb;
 		goto fs_out;
 	}
@@ -1468,168 +865,9 @@
 	return do_kern_mount((char *)type->name, 0, (char *)type->name, NULL);
 }
 
-static int do_add_mount(struct nameidata *nd, char *type, int flags,
-			int mnt_flags, char *name, void *data)
-{
-	struct vfsmount *mnt = do_kern_mount(type, flags, name, data);
-	int retval = PTR_ERR(mnt);
-
-	if (IS_ERR(mnt))
-		goto out;
-
-	mnt->mnt_flags = mnt_flags;
-
-	down(&mount_sem);
-	/* Something was mounted here while we slept */
-	while(d_mountpoint(nd->dentry) && follow_down(&nd->mnt, &nd->dentry))
-		;
-
-	/* Refuse the same filesystem on the same mount point */
-	if (nd->mnt->mnt_sb == mnt->mnt_sb && nd->mnt->mnt_root == nd->dentry)
-		retval = -EBUSY;
-	else
-		retval = graft_tree(mnt, nd);
-	up(&mount_sem);
-	mntput(mnt);
-out:
-	return retval;
-}
-
-static int copy_mount_options (const void *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 - 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;
-
-	/* 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;
-
-	/* 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);
-
-	/* ... and get the mountpoint */
-	if (path_init(dir_name, LOOKUP_FOLLOW|LOOKUP_POSITIVE, &nd))
-		retval = path_walk(dir_name, &nd);
-	if (retval)
-		return retval;
-
-	if (flags & MS_REMOUNT)
-		retval = do_remount(&nd, flags&~MS_REMOUNT, mnt_flags,
-				  (char *)data_page);
-	else if (flags & MS_BIND)
-		retval = do_loopback(&nd, dev_name);
-	else
-		retval = do_add_mount(&nd, type_page, flags, mnt_flags,
-				      dev_name, data_page);
-	path_release(&nd);
-	return retval;
-}
-
-asmlinkage long sys_mount(char * dev_name, char * dir_name, char * type,
-			  unsigned long flags, void * 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;
-}
-
 void __init mount_root(void)
 {
+	struct nameidata root_nd;
 	struct file_system_type * fs_type;
 	struct super_block * sb;
 	struct vfsmount *vfsmnt;
@@ -1639,6 +877,7 @@
 	void *handle;
 	char path[64];
 	int path_start = -1;
+	char *name = "/dev/root";
 
 #ifdef CONFIG_ROOT_NFS
 	void *data;
@@ -1776,13 +1015,24 @@
 		fs_type->name,
 		(sb->s_flags & MS_RDONLY) ? " readonly" : "");
 	if (path_start >= 0) {
+		name = path + path_start;
 		devfs_mk_symlink (NULL, "root", DEVFS_FL_DEFAULT,
-				  path + 5 + path_start, NULL, NULL);
-		memcpy (path + path_start, "/dev/", 5);
-		vfsmnt = add_vfsmnt(sb->s_root, path + path_start);
+				  name + 5, NULL, NULL);
+		memcpy (name, "/dev/", 5);
 	}
-	else
-		vfsmnt = add_vfsmnt(sb->s_root, "/dev/root");
+	vfsmnt = alloc_vfsmnt();
+	if (!vfsmnt)
+		panic("VFS: alloc_vfsmnt failed for root fs");
+
+	set_devname(vfsmnt, name);
+	vfsmnt->mnt_sb = sb;
+	vfsmnt->mnt_root = dget(sb->s_root);
+
+	root_nd.mnt = root_vfsmnt;
+	root_nd.dentry = root_vfsmnt->mnt_sb->s_root;
+	graft_tree(vfsmnt, &root_nd);
+	mntput(vfsmnt);
+
 	/* FIXME: if something will try to umount us right now... */
 	if (vfsmnt) {
 		set_fs_root(current->fs, vfsmnt, sb->s_root);
@@ -1791,274 +1041,4 @@
 			bdput(bdev); /* sb holds a reference */
 		return;
 	}
-	panic("VFS: add_vfsmnt failed for root fs");
-}
-
-
-static void chroot_fs_refs(struct dentry *old_root,
-			   struct vfsmount *old_rootmnt,
-			   struct dentry *new_root,
-			   struct vfsmount *new_rootmnt)
-{
-	struct task_struct *p;
-	struct fs_struct *fs;
-
-	read_lock(&tasklist_lock);
-	for_each_task(p) {
-		task_lock(p);
-		fs = p->fs;
-		if (fs) {
-			atomic_inc(&fs->count);
-			task_unlock(p);
-			if (fs->root==old_root && fs->rootmnt==old_rootmnt)
-				set_fs_root(fs, new_rootmnt, new_root);
-			if (fs->pwd==old_root && fs->pwdmnt==old_rootmnt)
-				set_fs_pwd(fs, new_rootmnt, new_root);
-			put_fs_struct(fs);
-		} else
-			task_unlock(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 *new_root, const char *put_old)
-{
-	struct dentry *root;
-	struct vfsmount *root_mnt;
-	struct vfsmount *tmp;
-	struct nameidata new_nd, old_nd, parent_nd, root_parent;
-	char *name;
-	int error;
-
-	if (!capable(CAP_SYS_ADMIN))
-		return -EPERM;
-
-	lock_kernel();
-
-	name = getname(new_root);
-	error = PTR_ERR(name);
-	if (IS_ERR(name))
-		goto out0;
-	error = 0;
-	if (path_init(name, LOOKUP_POSITIVE|LOOKUP_FOLLOW|LOOKUP_DIRECTORY, &new_nd))
-		error = path_walk(name, &new_nd);
-	putname(name);
-	if (error)
-		goto out0;
-
-	name = getname(put_old);
-	error = PTR_ERR(name);
-	if (IS_ERR(name))
-		goto out0;
-	error = 0;
-	if (path_init(name, LOOKUP_POSITIVE|LOOKUP_FOLLOW|LOOKUP_DIRECTORY, &old_nd))
-		error = path_walk(name, &old_nd);
-	putname(name);
-	if (error)
-		goto out1;
-
-	read_lock(&current->fs->lock);
-	root_mnt = mntget(current->fs->rootmnt);
-	root = dget(current->fs->root);
-	read_unlock(&current->fs->lock);
-	down(&mount_sem);
-	down(&old_nd.dentry->d_inode->i_zombie);
-	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 == root_mnt || old_nd.mnt == root_mnt)
-		goto out2; /* loop */
-	error = -EINVAL;
-	if (root_mnt->mnt_root != root)
-		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(&dcache_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(root_mnt, &root_parent);
-	attach_mnt(root_mnt, &old_nd);
-	if (root_parent.mnt != root_mnt)
-		attach_mnt(new_nd.mnt, &root_parent);
-	spin_unlock(&dcache_lock);
-	chroot_fs_refs(root,root_mnt,new_nd.dentry,new_nd.mnt);
-	error = 0;
-	if (root_parent.mnt != root_mnt)
-		path_release(&root_parent);
-	if (parent_nd.mnt != new_nd.mnt)
-		path_release(&parent_nd);
-out2:
-	up(&old_nd.dentry->d_inode->i_zombie);
-	up(&mount_sem);
-	dput(root);
-	mntput(root_mnt);
-	path_release(&old_nd);
-out1:
-	path_release(&new_nd);
-out0:
-	unlock_kernel();
-	return error;
-out3:
-	spin_unlock(&dcache_lock);
-	goto out2;
-}
-
-
-#ifdef CONFIG_BLK_DEV_INITRD
-
-int __init change_root(kdev_t new_root_dev,const char *put_old)
-{
-	struct vfsmount *old_rootmnt;
-	struct nameidata devfs_nd, nd;
-	int error = 0;
-
-	read_lock(&current->fs->lock);
-	old_rootmnt = mntget(current->fs->rootmnt);
-	read_unlock(&current->fs->lock);
-	/*  First unmount devfs if mounted  */
-	if (path_init("/dev", LOOKUP_FOLLOW|LOOKUP_POSITIVE, &devfs_nd))
-		error = path_walk("/dev", &devfs_nd);
-	if (!error) {
-		if (devfs_nd.mnt->mnt_sb->s_magic == DEVFS_SUPER_MAGIC &&
-		    devfs_nd.dentry == devfs_nd.mnt->mnt_root) {
-			down(&mount_sem);
-			do_umount(devfs_nd.mnt, 0);
-			path_release(&devfs_nd);
-			up(&mount_sem);
-		} else 
-			path_release(&devfs_nd);
-	}
-	ROOT_DEV = new_root_dev;
-	mount_root();
-#if 1
-	shrink_dcache();
-	printk("change_root: old root has d_count=%d\n", 
-	       atomic_read(&old_rootmnt->mnt_root->d_count));
-#endif
-	mount_devfs_fs ();
-	/*
-	 * Get the new mount directory
-	 */
-	error = 0;
-	if (path_init(put_old, LOOKUP_FOLLOW|LOOKUP_POSITIVE|LOOKUP_DIRECTORY, &nd))
-		error = path_walk(put_old, &nd);
-	if (error) {
-		int blivet;
-		struct block_device *ramdisk = old_rootmnt->mnt_sb->s_bdev;
-
-		atomic_inc(&ramdisk->bd_count);
-		blivet = blkdev_get(ramdisk, FMODE_READ, 0, BDEV_FS);
-		printk(KERN_NOTICE "Trying to unmount old root ... ");
-		if (!blivet) {
-			blivet = do_umount(old_rootmnt, 0);
-			mntput(old_rootmnt);
-			if (!blivet) {
-				int ioctl_err;
-
-				ioctl_err = ioctl_by_bdev(ramdisk, BLKFLSBUF, 0);
-				if (ioctl_err)
-					printk("failed to release ramdisk %d...", ioctl_err);
-				printk("okay\n");
-				error = 0;
-			}
-			blkdev_put(ramdisk, BDEV_FS);
-		}
-		if (blivet)
-			printk(KERN_ERR "error %d\n", blivet);
-		return error;
-	}
-	/* FIXME: we should hold i_zombie on nd.dentry */
-	move_vfsmnt(old_rootmnt, &nd, "/dev/root.old");
-	mntput(old_rootmnt);
-	path_release(&nd);
-	return 0;
-}
-
-#endif
-
-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, NULL, NULL);
-	if (!mnt_cache)
-		panic("Cannot create vfsmount cache");
-
-	mempages >>= (16 - PAGE_SHIFT);
-	mempages *= sizeof(struct list_head);
-	for (order = 0; ((1UL << order) << PAGE_SHIFT) < mempages; order++)
-		;
-
-	do {
-		mount_hashtable = (struct list_head *)
-			__get_free_pages(GFP_ATOMIC, order);
-	} while (mount_hashtable == NULL && --order >= 0);
-
-	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);
 }
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)