partially fix up the lookup_one_noperm mess

Try to fix the mess created by sysfs braindamage.

 - refactor code internal to fs/namei.c a little to avoid too much
   duplication:
	o __lookup_hash_kern is renamed back to __lookup_hash
	o the old __lookup_hash goes away, permission checks moves to
	  the two callers
	o useless inline qualifiers on above functions go away
 - lookup_one_len_kern loses it's last argument and is renamed to
   lookup_one_noperm to make it's useage a little more clear
 - added kerneldoc comments to describe lookup_one_len aswell as
   lookup_one_noperm and make it very clear that no one should use
   the latter ever.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/namei.h b/include/linux/namei.h
index 6c38efb..4cb4f8d 100644
--- a/include/linux/namei.h
+++ b/include/linux/namei.h
@@ -81,8 +81,8 @@
 extern struct file *nameidata_to_filp(struct nameidata *nd, int flags);
 extern void release_open_intent(struct nameidata *);
 
-extern struct dentry * lookup_one_len(const char *, struct dentry *, int);
-extern struct dentry *lookup_one_len_kern(const char *, struct dentry *, int);
+extern struct dentry *lookup_one_len(const char *, struct dentry *, int);
+extern struct dentry *lookup_one_noperm(const char *, struct dentry *);
 
 extern int follow_down(struct vfsmount **, struct dentry **);
 extern int follow_up(struct vfsmount **, struct dentry **);