Jeff Layton [off-list ref] wrote:

quoted

+	case FSCACHE_COOKIE_STATE_RELINQUISHING:
+	case FSCACHE_COOKIE_STATE_WITHDRAWING:
+		if (cookie->cache_priv) {
+			spin_unlock(&cookie->lock);
+			cookie->volume->cache->ops->withdraw_cookie(cookie);
+			spin_lock(&cookie->lock);
+		}
+
+		switch (state) {
+		case FSCACHE_COOKIE_STATE_RELINQUISHING:
+			fscache_see_cookie(cookie, fscache_cookie_see_relinquish);
+			fscache_unhash_cookie(cookie);
+			__fscache_set_cookie_state(cookie,
+						   FSCACHE_COOKIE_STATE_DROPPED);
+			wake = true;
+			goto out;
+		case FSCACHE_COOKIE_STATE_WITHDRAWING:
+			fscache_see_cookie(cookie, fscache_cookie_see_withdraw);
+			break;
+		default:
+			BUG();
+		}
+

Ugh, the nested switch here is a bit hard to follow. It makes it seem
like the state could change due to the withdraw_cookie and you're
checking it again, but it doesn't do that.

This would be clearer if you just duplicated the withdraw_cookie stanza
for both states and moved the stuff below here to a helper or to a new
goto block.

There are actually three states, but one's added in a later patch.  It
probably does make sense to split the RELINQ state from the other two.

David