[CIFS] revalidate parent inode when rmdir done within that directory

When a search is pending of a parent directory, and a child directory
within it is removed, we need to reset the parent directory's time
so that we don't reuse the (now stale) search results.

Thanks to Gunter Kukkukk for reporting this:

> got the following failure notification on irc #samba:
>
> A user was updating from subversion 1.4 to 1.5, where the
> repository is located on a samba share (independent of
> unix extensions = Yes or No).
> svn 1.4 did work, 1.5 does not.
>
> The user did a lot of stracing of subversion - and wrote a
> testapplet to simulate the failing behaviour.
> I've converted the C++ source to C and added some error cases.
>
> When using "./testdir" on a local file system, "result2"
> is always (nil) as expected - cifs vfs behaves different here!
>
>   ./testdir /mnt/cifs/mounted/share
>
> returns a (failing) valid pointer.

Acked-by: Dave Kleikamp <shaggy@us.ibm.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 5ab9896..bcf7b51 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1285,6 +1285,11 @@
 	cifsInode = CIFS_I(direntry->d_inode);
 	cifsInode->time = 0;	/* force revalidate to go get info when
 				   needed */
+
+	cifsInode = CIFS_I(inode);
+	cifsInode->time = 0;	/* force revalidate to get parent dir info
+				   since cached search results now invalid */
+
 	direntry->d_inode->i_ctime = inode->i_ctime = inode->i_mtime =
 		current_fs_time(inode->i_sb);