From patchwork Fri Aug 28 09:12:35 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Antonio Quartulli X-Patchwork-Id: 4715 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=5.148.176.57; helo=s1.neomailbox.net; envelope-from=antonio@meshcoding.com; receiver=b.a.t.m.a.n@lists.open-mesh.org Received: from s1.neomailbox.net (s1.neomailbox.net [5.148.176.57]) by open-mesh.org (Postfix) with ESMTPS id 94FC780554 for ; Fri, 28 Aug 2015 11:14:03 +0200 (CEST) From: Antonio Quartulli To: davem@davemloft.net Date: Fri, 28 Aug 2015 11:12:35 +0200 Message-Id: <1440753156-7808-10-git-send-email-antonio@meshcoding.com> In-Reply-To: <1440753156-7808-1-git-send-email-antonio@meshcoding.com> References: <1440753156-7808-1-git-send-email-antonio@meshcoding.com> Cc: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org, Antonio Quartulli , Marek Lindner Subject: [B.A.T.M.A.N.] [PATCH 09/10] batman-adv: Add lower layer needed_(head|tail)room to own ones X-BeenThere: b.a.t.m.a.n@lists.open-mesh.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: The list for a Better Approach To Mobile Ad-hoc Networking List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 28 Aug 2015 09:14:03 -0000 From: Sven Eckelmann The maximum of hard_header_len and maximum of all needed_(head|tail)room of all slave interfaces of a batman-adv device must be used to define the batman-adv device needed_(head|tail)room. This is required to avoid too small buffer problems when these slave devices try to send the encapsulated packet in a tx path without the possibility to resize the skbuff. Signed-off-by: Sven Eckelmann Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli --- net/batman-adv/hard-interface.c | 41 +++++++++++++++++++++++++++++++++++++++++ net/batman-adv/soft-interface.c | 2 -- 2 files changed, 41 insertions(+), 2 deletions(-) diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index 0565b20..f11345e 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -252,6 +252,44 @@ static void batadv_check_known_mac_addr(const struct net_device *net_dev) rcu_read_unlock(); } +/** + * batadv_hardif_recalc_extra_skbroom() - Recalculate skbuff extra head/tailroom + * @soft_iface: netdev struct of the mesh interface + */ +static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface) +{ + const struct batadv_hard_iface *hard_iface; + unsigned short lower_header_len = ETH_HLEN; + unsigned short lower_headroom = 0; + unsigned short lower_tailroom = 0; + unsigned short needed_headroom; + + rcu_read_lock(); + list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { + if (hard_iface->if_status == BATADV_IF_NOT_IN_USE) + continue; + + if (hard_iface->soft_iface != soft_iface) + continue; + + lower_header_len = max_t(unsigned short, lower_header_len, + hard_iface->net_dev->hard_header_len); + + lower_headroom = max_t(unsigned short, lower_headroom, + hard_iface->net_dev->needed_headroom); + + lower_tailroom = max_t(unsigned short, lower_tailroom, + hard_iface->net_dev->needed_tailroom); + } + rcu_read_unlock(); + + needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN); + needed_headroom += batadv_max_header_len(); + + soft_iface->needed_headroom = needed_headroom; + soft_iface->needed_tailroom = lower_tailroom; +} + int batadv_hardif_min_mtu(struct net_device *soft_iface) { struct batadv_priv *bat_priv = netdev_priv(soft_iface); @@ -474,6 +512,8 @@ int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface, "Not using interface %s (retrying later): interface not active\n", hard_iface->net_dev->name); + batadv_hardif_recalc_extra_skbroom(soft_iface); + /* begin scheduling originator messages on that interface */ batadv_schedule_bat_ogm(hard_iface); @@ -529,6 +569,7 @@ void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface, dev_put(hard_iface->soft_iface); netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface); + batadv_hardif_recalc_extra_skbroom(hard_iface->soft_iface); /* nobody uses this interface anymore */ if (!bat_priv->num_ifaces) { diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index d5c5ad9..ac4d08d 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -947,8 +947,6 @@ static void batadv_softif_init_early(struct net_device *dev) * have not been initialized yet */ dev->mtu = ETH_DATA_LEN; - /* reserve more space in the skbuff for our header */ - dev->hard_header_len = batadv_max_header_len(); /* generate random address */ eth_hw_addr_random(dev);