coda: correctly invalidate cached access rights

Change the epoch value to forces a refresh instead of clearing the cached
rights mask and block all further accesses to the object.
Signed-off-by: NJan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/coda/cache.c

@@ -43,7 +43,7 @@ void coda_cache_enter(struct inode *inode, int mask)
 void coda_cache_clear_inode(struct inode *inode)
 {
 	struct coda_inode_info *cii = ITOC(inode);
-        cii->c_cached_perm = 0;
+	cii->c_cached_epoch = atomic_read(&permission_epoch) - 1;
 }
 
 /* remove all acl caches */