inode numbering: change libfs sb creation routines to avoid collisions with their root inodes

This patch makes it so that simple_fill_super and get_sb_pseudo assign their
root inodes to be number 1.  It also fixes up a couple of callers of
simple_fill_super that were passing in files arrays that had an index at
number 1, and adds a warning for any caller that sends in such an array.

It would have been nice to have made it so that it wasn't possible to make
such a collision, but some callers need to be able to control what inode
number their entries get, so I think this is the best that can be done.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
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/fs/binfmt_misc.c b/fs/binfmt_misc.c
index e6f5799..18657f0 100644
--- a/fs/binfmt_misc.c
+++ b/fs/binfmt_misc.c
@@ -727,8 +727,8 @@
 static int bm_fill_super(struct super_block * sb, void * data, int silent)
 {
 	static struct tree_descr bm_files[] = {
-		[1] = {"status", &bm_status_operations, S_IWUSR|S_IRUGO},
-		[2] = {"register", &bm_register_operations, S_IWUSR},
+		[2] = {"status", &bm_status_operations, S_IWUSR|S_IRUGO},
+		[3] = {"register", &bm_register_operations, S_IWUSR},
 		/* last one */ {""}
 	};
 	int err = simple_fill_super(sb, 0x42494e4d, bm_files);