From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH 6/6] virtio-scsi: Enable DIF/DIX modes in SCSI host LLD Date: Mon, 19 May 2014 22:15:27 +0300 Message-ID: <20140519191527.GC32382@redhat.com> References: <1396819929-29687-1-git-send-email-nab@daterainc.com> <1396819929-29687-7-git-send-email-nab@daterainc.com> <20140407084518.GA14091@redhat.com> <1396861019.19888.25.camel@haakon3.risingtidesystems.com> <20140507091305.GA20044@redhat.com> <1400526423.10964.31.camel@haakon3.risingtidesystems.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1400526423.10964.31.camel@haakon3.risingtidesystems.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: "Nicholas A. Bellinger" Cc: linux-scsi , "Martin K. Petersen" , Sagi Grimberg , virtualization@lists.linux-foundation.org, Sagi Grimberg , target-devel , "H. Peter Anvin" , Paolo Bonzini , "Nicholas A. Bellinger" , Christoph Hellwig List-Id: linux-scsi@vger.kernel.org On Mon, May 19, 2014 at 12:07:03PM -0700, Nicholas A. Bellinger wrote: > On Wed, 2014-05-07 at 12:13 +0300, Michael S. Tsirkin wrote: > > On Mon, Apr 07, 2014 at 01:56:59AM -0700, Nicholas A. Bellinger wrote: > > > On Mon, 2014-04-07 at 11:45 +0300, Michael S. Tsirkin wrote: > > > > On Sun, Apr 06, 2014 at 09:32:09PM +0000, Nicholas A. Bellinger wrote: > > > > > From: Nicholas Bellinger > > > > > > > > > > This patch updates virtscsi_probe() to setup necessary Scsi_Host > > > > > level protection resources. (currently hardcoded to 1) > > > > > > > > > > It changes virtscsi_add_cmd() to attach outgoing / incoming > > > > > protection SGLs preceeding the data payload, and is using the > > > > > new virtio_scsi_cmd_req_pi->d[oi],pi_niv field to signal > > > > > to signal to vhost/scsi how many prot_sgs to expect. > > > > > > > > > > v3 changes: > > > > > - Use VIRTIO_SCSI_F_T10_PI to determine PI or non PI header (Paolo) > > > > > > > > > > v2 changes: > > > > > - Make protection buffer come before data buffer (Paolo) > > > > > - Enable virtio_scsi_cmd_req_pi usage (Paolo) > > > > > > > > > > Cc: Paolo Bonzini > > > > > Cc: Michael S. Tsirkin > > > > > Cc: Martin K. Petersen > > > > > Cc: Christoph Hellwig > > > > > Cc: Hannes Reinecke > > > > > Cc: Sagi Grimberg > > > > > Cc: H. Peter Anvin > > > > > Signed-off-by: Nicholas Bellinger > > > > > > > > OK but we need to document the new interface in the spec > > > > (and incidentially, this will be useful to verify the assumptions > > > > made here and on the host side). > > > > Could you please submit this proposal to the OASIS Virtio TC > > > > for inclusion into the next spec draft? > > > > Ideally as a patch against the tex source, but a prose > > > > description would do as well. > > > > > > Most certainly. Please give me a bit to follow up on this, as the next > > > couple of days are going to be hellishly busy.. > > > > Ping. > > We really need to get this moving to have the interface reviewed for > > the next merge window. > > > > Hi MST, > > So I've finally got some cycles to get back to this code, and wanted to > verify the outstanding items you had previously raised: > > - Convert vhost-scsi to be independent of IOV layout using > memcpy_fromiovecend. (Does this effect existing non PI virtio-scsi > operation..?) Ideally yes. > - Report VIRTIO_F_ANY_LAYOUT feature bit to userspace. > - Convert virtio_scsi_cmd_req_pi to bytes field instead of number of > iovecs. > - Ensure virtio_scsi_cmd_req_pi is naturally aligned It turns out other virtio scsi commands aren't aligned? If true we don't need to make an exception here. > - Figure out why QEMU is not acking (any) vhost-scsi feature bits > > Is there anything else that you'd like to see for an initial merge, or > other issues that need to be addressed with the above..? > > --nab FYI Paolo sent a spec patch for the feature. Have you seen it? -- MST