[Stgt-devel] Linux Kernel Version

[FUJITA Tomonori]

From: Tom Tucker <tom at opengridcomputing.com>
Subject: Re: [Stgt-devel] Linux Kernel Version
Date: Thu, 13 Jul 2006 10:00:33 -0500

> > As you said, it's complicated to run tgt right now. I've been working
> > on it because some people might be interested in tgt after OLS. I want
> > to make sure that everyone can run tgt without effort. I'm in the
> > middle of large user-space rewrite (I've commited some last night).
> > 
> > Sorry for delay about iSER tgt stuff. I will work on it after OLS. 
> 
> The biggest thing I'd like some guidance on is how we want to plug into
> the transport switch. If connection management (not LOGIN, just the 
> listen/accept paths), is pushed into the kernel, then the user-mode
> code is insulated from the transport switch. This requires pushing the 
> current TCP connection management into the kernel though and adding netlink 
> messages for listen/accept. 
> 
> Otherwise, we need to replicate the switch in user-mode. The TCP tgt can
> still use sockets in user mode, but he RDMA side will need to have the 
> netlink messages anyway. The issue is that unlike a socket, the RDMA 
> user-mode CM doesn't have the ability to have user-mode code and 
> kernel-mode code both doing I/O on the transport like a socket. 
> 
> I've coded up the kernel-only approach, but haven't gotten much feedback 
> on it, so I'm assuming that it's not the preferred method ;-)

I guess that you are doing something like open-iscsi iSER code (the
user-space daemon asks the kernel module to do transport staff, called
endpoint in open-iscsi). It is fine by me. I will read your patch
(really sorry about delay again) and merge it.


> > If
> > you guys teach me how to setup Chelsio T3 at OLS, I can work on it
> > right after OLS. :)
> 
> Here's a How-To on bringing up the Chelsio code for RDMA

Looks really helpful. Thanks. I'll try after OLS.