From patchwork Mon Nov 29 02:09:51 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Levitsky X-Patchwork-Id: 73360 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 0604EB70A7 for ; Mon, 29 Nov 2010 13:10:42 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754465Ab0K2CKh (ORCPT ); Sun, 28 Nov 2010 21:10:37 -0500 Received: from mail-bw0-f46.google.com ([209.85.214.46]:48670 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754096Ab0K2CKg (ORCPT ); Sun, 28 Nov 2010 21:10:36 -0500 Received: by mail-bw0-f46.google.com with SMTP id 15so3474612bwz.19 for ; Sun, 28 Nov 2010 18:10:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:from:to:cc:subject:date :message-id:x-mailer:in-reply-to:references; bh=pW6SSMHNAIP/kQ9+DZEe7xrHevtyKE4JCQ4pwxl7ONk=; b=id5EF98ibY+rt9/47jgnr7esyVvxxby3qOjlapHoUhPzp2yjllcQ0FVFiJb8kMIEH/ IvfimJWZl7UNTE5g3c+NPnok2EwbFq/8A0zHiPbB7FaXSI6tPvg4cP3PqI6tp0SGctoy VkY39bSJiSOm1yje21xpENZVqA4571RZ2yO84= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=gyaJFvkqsd7JDUPJoECuh/cn8qMn3jsTTB7pf4JO4rZac8u6CTOr5HkO5v2b9XTdYg RfksqXZYJ4KRYDrwKrOsby9TXppkuCfP5A6yD/3upcJ9OcVczwXFVAoYvboWMbjZT4tw DXGg7eWo5DnZ798Z6pp8v9r1/bxzd0jEGjRtk= Received: by 10.204.79.9 with SMTP id n9mr4273022bkk.126.1290996636006; Sun, 28 Nov 2010 18:10:36 -0800 (PST) Received: from maxim-laptop ([77.125.106.104]) by mx.google.com with ESMTPS id p22sm1742200bkp.9.2010.11.28.18.10.33 (version=SSLv3 cipher=RC4-MD5); Sun, 28 Nov 2010 18:10:34 -0800 (PST) From: Maxim Levitsky To: linux1394-devel Cc: Stefan Richter , netdev@vger.kernel.org, Maxim Levitsky , "David S. Miller" , Alexey Kuznetsov , James Morris , Patrick McHardy Subject: [PATCH 3/5] NET: IPV4: ARP: allow to invalidate specific ARP entries Date: Mon, 29 Nov 2010 04:09:51 +0200 Message-Id: <1290996593-32416-4-git-send-email-maximlevitsky@gmail.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1290996593-32416-1-git-send-email-maximlevitsky@gmail.com> References: <1290996593-32416-1-git-send-email-maximlevitsky@gmail.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org IPv4 over firewire needs to be able to remove ARP entries from the ARP cache that belong to nodes that are removed, because IPv4 over firewire uses ARP packets for private information about nodes. This information becomes invalid as soon as node drops off the bus and when it reconnects, its only possible to start takling to is after it responded to an ARP packet. But ARP cache prevents such packets from being sent. CC: netdev@vger.kernel.org CC: "David S. Miller" CC: Alexey Kuznetsov CC: James Morris CC: Patrick McHardy Signed-off-by: Maxim Levitsky --- include/net/arp.h | 1 + net/ipv4/arp.c | 29 ++++++++++++++++++----------- 2 files changed, 19 insertions(+), 11 deletions(-) diff --git a/include/net/arp.h b/include/net/arp.h index f4cf6ce..91f0568 100644 --- a/include/net/arp.h +++ b/include/net/arp.h @@ -25,5 +25,6 @@ extern struct sk_buff *arp_create(int type, int ptype, __be32 dest_ip, const unsigned char *src_hw, const unsigned char *target_hw); extern void arp_xmit(struct sk_buff *skb); +int arp_invalidate(struct net_device *dev, __be32 ip); #endif /* _ARP_H */ diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index d8e540c..35b1272 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -1142,6 +1142,23 @@ static int arp_req_get(struct arpreq *r, struct net_device *dev) return err; } +int arp_invalidate(struct net_device *dev, __be32 ip) +{ + int err = -ENXIO; + struct neighbour *neigh = neigh_lookup(&arp_tbl, &ip, dev); + + if (neigh) { + if (neigh->nud_state & ~NUD_NOARP) + err = neigh_update(neigh, NULL, NUD_FAILED, + NEIGH_UPDATE_F_OVERRIDE| + NEIGH_UPDATE_F_ADMIN); + neigh_release(neigh); + } + + return err; +} +EXPORT_SYMBOL(arp_invalidate); + static int arp_req_delete_public(struct net *net, struct arpreq *r, struct net_device *dev) { @@ -1162,7 +1179,6 @@ static int arp_req_delete(struct net *net, struct arpreq *r, { int err; __be32 ip; - struct neighbour *neigh; if (r->arp_flags & ATF_PUBL) return arp_req_delete_public(net, r, dev); @@ -1180,16 +1196,7 @@ static int arp_req_delete(struct net *net, struct arpreq *r, if (!dev) return -EINVAL; } - err = -ENXIO; - neigh = neigh_lookup(&arp_tbl, &ip, dev); - if (neigh) { - if (neigh->nud_state & ~NUD_NOARP) - err = neigh_update(neigh, NULL, NUD_FAILED, - NEIGH_UPDATE_F_OVERRIDE| - NEIGH_UPDATE_F_ADMIN); - neigh_release(neigh); - } - return err; + return arp_invalidate(dev, ip); } /*