From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Steve Wise" Subject: RE: [PATCH 0/3] RDMA/core: iWARP Port Mapper Overview Date: Mon, 9 Jun 2014 09:46:48 -0500 Message-ID: <000801cf83f1$a4366920$eca33b60$@opengridcomputing.com> References: <20140326220718.GA8784@TENIKOLO-MOBL1> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Return-path: In-Reply-To: Content-Language: en-us Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: 'Or Gerlitz' , 'Tatyana Nikolova' Cc: 'Roland Dreier' , "'Lacombe, John S'" , 'Sean Hefty' , 'linux-rdma' , 'Jason Gunthorpe' List-Id: linux-rdma@vger.kernel.org > > Hi Steve, Tatyana > > Reading this cover letter, I think it's good idea to follow Steve's > suggestion and add portions from here into the IB/core change you > introduced (patch #1 in this series) and is now merged into Roland's > for-next -- before Roland's sends his 3.16 merge window pull request > to Linus (there is enough time!!), since the current change-log > http://git.kernel.org/cgit/linux/kernel/git/roland/infiniband.git/commit/?h=for- > next&id=1943d56776ad31a119517efeb309786db3b4383e > practically says nothing on what is the PM about > Roland, can you do this? > 2nd, there's nothing specific to iWARP in the port mapper implementation, right? > > What it does is the following: > > 1. kernel rdma driver tells a user space daemon they want to reserve > (claim) the combination of IP address X and TCP port Y for the sake of > RDMA connections > > 2. user space daemon opens a socket and binds to X:Y > No, the use space daemon opens a socket and binds to address X port 0 and thus allocates an ephemeral port number Z. The mapping of X->Z is then made available to clients trying to connect to this service. > Specifically, down the road, more use cases, not only the current > iWARP case may pop up. > It is really only needed for iWARP and not IB because IB doesn't share the port space with the host TCP stack. iWARP does. > So taking into account that the implementation doesn't have anything > whivh is IW specific, and that future non-IW use case might show up, > why we need to fill the IB core code with IW_PM notation? why not just > use RDMA_PM notation? this can be achieved quickly with > > $ sed -i g/iw_pm/rdma_pm/g * > > and friends on Roland's tree and later squashed into the relevant patches. > > I understand that my comment came little late... but taking into > account the ease of the change (sed exercise), why not doing it? the > IB core patch exposes API to user-space, so we should make sure to do > it right > I'm not convinced this is desirable. Steve. -- 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