Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753857AbZIALMZ (ORCPT ); Tue, 1 Sep 2009 07:12:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753197AbZIALMY (ORCPT ); Tue, 1 Sep 2009 07:12:24 -0400 Received: from mail-ew0-f206.google.com ([209.85.219.206]:58190 "EHLO mail-ew0-f206.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752817AbZIALMX (ORCPT ); Tue, 1 Sep 2009 07:12:23 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; b=JFkGTkzbskJxax+qZ0XFGBr7BqiSuq18ExleEcmYT0jzd/QpCACl7LkRBL+0K6Oknc 2cS5IDAxzp0llv6kv44b0A+3mG6aGUgwB7zSBCljXb7G7K9JHOuUZg7Wp++tZeAx2100 8NPuSUDz+ZlWVUvmzVzDu2nREXlxBh70a1bQo= MIME-Version: 1.0 In-Reply-To: <1251741624.18828.83.camel@mulgrave.site> References: <1251415060.16297.58.camel@ank32.eng.vmware.com> <1251739735.16169.20.camel@ank32.eng.vmware.com> <1251741624.18828.83.camel@mulgrave.site> Date: Tue, 1 Sep 2009 13:12:24 +0200 X-Google-Sender-Auth: 8611d1db0ed427a0 Message-ID: Subject: Re: [PATCH] SCSI driver for VMware's virtual HBA. From: Bart Van Assche To: James Bottomley Cc: akataria@vmware.com, Robert Love , Randy Dunlap , Mike Christie , linux-scsi@vger.kernel.org, LKML , Andrew Morton , Dmitry Torokhov , Rolf Eike Beer , Maxime Austruy Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1784 Lines: 40 On Mon, Aug 31, 2009 at 8:00 PM, James Bottomley wrote: > > On Mon, 2009-08-31 at 10:28 -0700, Alok Kataria wrote: > > VMware PVSCSI driver - v2. > > OK, so the first thing that springs to mind is that we already have one > of these things: the ibmvscsi ... is there no way we can share code > between this and the other PV drivers? Good question. But shouldn't the ibmvscsi driver be refactored before considering sharing ibmvscsi code with other paravirtualized drivers ? A quote from the ibmvscsi.c source code: * TODO: This is currently pretty tied to the IBM i/pSeries hypervisor * interfaces. It would be really nice to abstract this above an RDMA * layer. Splitting the ibmvscsi.c driver in an SRP initiator and an RDMA driver would make the following possible: - Reuse the existing SRP initiator (ib_srp). Currently there are two SRP initiators present in the Linux kernel -- one that uses the RDMA verbs API (ib_srp) and one that only works with IBM's i/pSeries hypervisor (ibmvscsi). - Reuse the ib_ipoib kernel module to provide an IP stack on top of the new RDMA driver instead of having to maintain a separate network driver for this hardware (ibmveth). More information about the architecture the ibmvscsi and the ibmveth drivers have been developed for can be found in the following paper: D. Boutcher and D. Engebretsen, Linux Virtualization on IBM POWER5 Systems, Proceedings of the Linux Symposium, Vol. 1, July 2004, pp. 113-120 (http://www.kernel.org/doc/mirror/ols2004v1.pdf). Bart. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/