From mboxrd@z Thu Jan 1 00:00:00 1970 From: Or Gerlitz Subject: Re: [PATCH REPOST libibverbs] Add IP and TCP/UDP TX checksum offload support Date: Tue, 11 Aug 2015 11:39:52 +0300 Message-ID: References: <1434276784-15909-1-git-send-email-ogerlitz@mellanox.com> <20150618163842.GA14348@obsidianresearch.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <20150618163842.GA14348-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jason Gunthorpe Cc: Or Gerlitz , Doug Ledford , "linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Amir Vadai , Tal Alon , Matan Barak , Moshe Lazer , Bodong Wang List-Id: linux-rdma@vger.kernel.org On Thu, Jun 18, 2015 at 7:38 PM, Jason Gunthorpe wrote: > On Sun, Jun 14, 2015 at 01:13:04PM +0300, Or Gerlitz wrote: >> From: Moshe Lazer >> >> Add a device capability flag IB_DEVICE_IP_SUM to denote checksum offload >> support. Devices should set this flag if they support insertion of IP, TCP >> and UDP checksums on outgoing IP packets sent over IB UD or ETH RAW_PACKET QPs. > > It would be really nice to see the man page discuss exactly what is > done here, there are quite a few different options for checksum. > > IPoIB maps this to 'NETIF_F_IP_CSUM', so only UDP/TCP checksum in > IPv4. > > What value should be placed in the checksum header(s) prior to issuing > the send? It looks like IPoIB uses the CHECKSUM_PARTIAL protocol ? yes, we can follow here on how IPoIB uses this device capability. In that case, AFAIK and from quick look on the TX section for CHECKSUM_PARTIAL in include/linux/skbuff.h -- nothing special is assumed to be placed in the checksum field at the header/s prior to issuing the send, agree? Or. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html