From owner-freebsd-net@FreeBSD.ORG Thu Feb 16 18:19:06 2012 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5C010106566C for ; Thu, 16 Feb 2012 18:19:06 +0000 (UTC) (envelope-from david.somayajulu@qlogic.com) Received: from TX2EHSOBE003.bigfish.com (tx2ehsobe002.messaging.microsoft.com [65.55.88.12]) by mx1.freebsd.org (Postfix) with ESMTP id 0A9048FC17 for ; Thu, 16 Feb 2012 18:19:05 +0000 (UTC) Received: from mail11-tx2-R.bigfish.com (10.9.14.243) by TX2EHSOBE003.bigfish.com (10.9.40.23) with Microsoft SMTP Server id 14.1.225.23; Thu, 16 Feb 2012 18:04:02 +0000 Received: from mail11-tx2 (localhost [127.0.0.1]) by mail11-tx2-R.bigfish.com (Postfix) with ESMTP id E401C801B5 for ; Thu, 16 Feb 2012 18:04:01 +0000 (UTC) X-SpamScore: -7 X-BigFish: VPS-7(zzc85fh14ffOzz1202hzz8275bh8275dhz2fh2a8h668h839h) X-Forefront-Antispam-Report: CIP:198.70.193.61; KIP:(null); UIP:(null); IPV:NLI; H:avexcashub1.qlogic.com; RD:avexcashub1.qlogic.com; EFVD:NLI Received-SPF: pass (mail11-tx2: domain of qlogic.com designates 198.70.193.61 as permitted sender) client-ip=198.70.193.61; envelope-from=david.somayajulu@qlogic.com; helo=avexcashub1.qlogic.com ; 1.qlogic.com ; Received: from mail11-tx2 (localhost.localdomain [127.0.0.1]) by mail11-tx2 (MessageSwitch) id 1329415438526882_31299; Thu, 16 Feb 2012 18:03:58 +0000 (UTC) Received: from TX2EHSMHS037.bigfish.com (unknown [10.9.14.247]) by mail11-tx2.bigfish.com (Postfix) with ESMTP id 7357F400053 for ; Thu, 16 Feb 2012 18:03:58 +0000 (UTC) Received: from avexcashub1.qlogic.com (198.70.193.61) by TX2EHSMHS037.bigfish.com (10.9.99.137) with Microsoft SMTP Server (TLS) id 14.1.225.23; Thu, 16 Feb 2012 18:03:57 +0000 Received: from avexmb1.qlogic.org ([fe80::9545:3a4f:c131:467d]) by avexcashub1.qlogic.org ([::1]) with mapi; Thu, 16 Feb 2012 10:03:56 -0800 From: David Somayajulu To: "freebsd-net@freebsd.org" Date: Thu, 16 Feb 2012 10:03:54 -0800 Thread-Topic: Question on TSO/LSO Transmit Frames Thread-Index: Aczs0/lQTU+h9exiQKid5+rFLlzfiA== Message-ID: <75E1A2A7D185F841A975979B0906BBA67C79BD85EB@AVEXMB1.qlogic.org> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US MIME-Version: 1.0 X-OriginatorOrg: qlogic.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Subject: Question on TSO/LSO Transmit Frames X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 16 Feb 2012 18:19:06 -0000 Hi All, Is it safe to assume that when a driver receives an Ethernet frame to trans= mit with CSUM_TSO bit set in m_head->m_pkthdr.csum_flags ; where m_head is the first (struct mbuf) in t= he mbuf chain that the [Ethernet Header] + [VLAN Tag if present] + [IP Header] + [TCP Hea= der] are all present in one physically contiguous segment ? In other words is Size of ([Ethernet Header] + [VLAN Tag if present] + [IP Header] + [TCP Hea= der]) <=3D m_head->m_len When ((m_head->m_pkthdr.csum_flags & CSUM_TSO) !=3D 0) Thanks David S. ________________________________ This message and any attached documents contain information from QLogic Cor= poration or its wholly-owned subsidiaries that may be confidential. If you = are not the intended recipient, you may not read, copy, distribute, or use = this information. If you have received this transmission in error, please n= otify the sender immediately by reply e-mail and then delete this message.