From patchwork Fri Nov 8 01:42:09 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tuong Lien X-Patchwork-Id: 1191551 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=dektech.com.au Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=dektech.com.au header.i=@dektech.com.au header.b="SugZYM7d"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 478NLb58Xtz9sPF for ; Fri, 8 Nov 2019 12:42:31 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728574AbfKHBm2 (ORCPT ); Thu, 7 Nov 2019 20:42:28 -0500 Received: from f0-dek.dektech.com.au ([210.10.221.142]:32928 "EHLO mail.dektech.com.au" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725930AbfKHBm1 (ORCPT ); Thu, 7 Nov 2019 20:42:27 -0500 Received: from localhost (localhost [127.0.0.1]) by mail.dektech.com.au (Postfix) with ESMTP id 4F77E4AAFB; Fri, 8 Nov 2019 12:42:23 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=dektech.com.au; h=references:in-reply-to:x-mailer:message-id:date:date:subject :subject:from:from:received:received:received; s=mail_dkim; t= 1573177343; bh=WsAHGtvnt886PVnpqF4ThKKTW7gJtIaWyQTSJX5MOGk=; b=S ugZYM7dt8Clz6R3i6wGBpPqr86x2OR0roch29fWQVbrST3qtKJwaqUthrW7iPmaK nm7GiBGA8aUMHk/EQj6fOsgf69nHhv6f5ZXpPI9C9r2z55ScsdOKwClyGeSEVbE8 MlnzDulVjAHELZmhxgIK97F/k0T+SoS5wGAJXOwePE= X-Virus-Scanned: amavisd-new at dektech.com.au Received: from mail.dektech.com.au ([127.0.0.1]) by localhost (mail2.dektech.com.au [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id yO1Y6oMCNFM8; Fri, 8 Nov 2019 12:42:23 +1100 (AEDT) Received: from mail.dektech.com.au (localhost [127.0.0.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.dektech.com.au (Postfix) with ESMTPS id 347784AAFC; Fri, 8 Nov 2019 12:42:23 +1100 (AEDT) Received: from localhost.localdomain (unknown [14.161.14.188]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.dektech.com.au (Postfix) with ESMTPSA id 1D9194AAFB; Fri, 8 Nov 2019 12:42:21 +1100 (AEDT) From: Tuong Lien To: davem@davemloft.net, jon.maloy@ericsson.com, maloy@donjonn.com, ying.xue@windriver.com, netdev@vger.kernel.org Cc: tipc-discussion@lists.sourceforge.net Subject: [net-next 1/5] tipc: add reference counter to bearer Date: Fri, 8 Nov 2019 08:42:09 +0700 Message-Id: <20191108014213.32219-2-tuong.t.lien@dektech.com.au> X-Mailer: git-send-email 2.13.7 In-Reply-To: <20191108014213.32219-1-tuong.t.lien@dektech.com.au> References: <20191108014213.32219-1-tuong.t.lien@dektech.com.au> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org As a need to support the crypto asynchronous operations in the later commits, apart from the current RCU mechanism for bearer pointer, we add a 'refcnt' to the bearer object as well. So, a bearer can be hold via 'tipc_bearer_hold()' without being freed even though the bearer or interface can be disabled in the meanwhile. If that happens, the bearer will be released then when the crypto operation is completed and 'tipc_bearer_put()' is called. Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien --- net/tipc/bearer.c | 14 +++++++++++++- net/tipc/bearer.h | 3 +++ 2 files changed, 16 insertions(+), 1 deletion(-) diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c index 0214aa1c4427..6e15b9b1f1ef 100644 --- a/net/tipc/bearer.c +++ b/net/tipc/bearer.c @@ -315,6 +315,7 @@ static int tipc_enable_bearer(struct net *net, const char *name, b->net_plane = bearer_id + 'A'; b->priority = prio; test_and_set_bit_lock(0, &b->up); + refcount_set(&b->refcnt, 1); res = tipc_disc_create(net, b, &b->bcast_addr, &skb); if (res) { @@ -351,6 +352,17 @@ static int tipc_reset_bearer(struct net *net, struct tipc_bearer *b) return 0; } +bool tipc_bearer_hold(struct tipc_bearer *b) +{ + return (b && refcount_inc_not_zero(&b->refcnt)); +} + +void tipc_bearer_put(struct tipc_bearer *b) +{ + if (b && refcount_dec_and_test(&b->refcnt)) + kfree_rcu(b, rcu); +} + /** * bearer_disable * @@ -369,7 +381,7 @@ static void bearer_disable(struct net *net, struct tipc_bearer *b) if (b->disc) tipc_disc_delete(b->disc); RCU_INIT_POINTER(tn->bearer_list[bearer_id], NULL); - kfree_rcu(b, rcu); + tipc_bearer_put(b); tipc_mon_delete(net, bearer_id); } diff --git a/net/tipc/bearer.h b/net/tipc/bearer.h index ea0f3c49cbed..faca696d422f 100644 --- a/net/tipc/bearer.h +++ b/net/tipc/bearer.h @@ -165,6 +165,7 @@ struct tipc_bearer { struct tipc_discoverer *disc; char net_plane; unsigned long up; + refcount_t refcnt; }; struct tipc_bearer_names { @@ -210,6 +211,8 @@ int tipc_media_set_window(const char *name, u32 new_value); int tipc_media_addr_printf(char *buf, int len, struct tipc_media_addr *a); int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b, struct nlattr *attrs[]); +bool tipc_bearer_hold(struct tipc_bearer *b); +void tipc_bearer_put(struct tipc_bearer *b); void tipc_disable_l2_media(struct tipc_bearer *b); int tipc_l2_send_msg(struct net *net, struct sk_buff *buf, struct tipc_bearer *b, struct tipc_media_addr *dest);