From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756678Ab0FGJCJ (ORCPT ); Mon, 7 Jun 2010 05:02:09 -0400 Received: from smtp126.sbc.mail.sp1.yahoo.com ([69.147.65.185]:30228 "HELO smtp126.sbc.mail.sp1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1756662Ab0FGJCG (ORCPT ); Mon, 7 Jun 2010 05:02:06 -0400 X-Yahoo-SMTP: fzDSGlOswBCWnIOrNw7KwwK1j9PqyNbe5PtLKiS4dDU.UNl_t6bdEZu9tTLW X-YMail-OSG: ne8aBTMVM1lH5Ow1g6gIZppFbTvrDvODTkWZkLB3qhqv76D_6Yt37uUSWRN_9LG1XiH2_DjL2rXPeIaIfynmHrNDszu_.JJy1ZC3s4eIr_ZkO3gHoh0y53kEeGgsWY9C9QtZjK_FUTwYSTF510hJV8LxhP_kG7F4E84Uzera2kIRxBhNMVd3dmFMKAGt2nxnoKnIkLxgNmhgx5M2LIadl7RcszktgLKVsSnnFeAqWO1muzJodB0c6vR4VZwQv1eZF9ALTUFOn_ML5ZHidmN2su2bGUIUDQGjIFpjtPpyEnaol_YgBr6Lbjyj19NwG1Fh6Kf_wA18piEWP2Rutgt881mJIyF994OOfbha71M1gJtj_A-- X-Yahoo-Newman-Property: ymail-3 Subject: Re: [PATCH 3/3] [tgt]: Add BSG v4 backstore support to usr/bs_sg.c From: "Nicholas A. Bellinger" To: Boaz Harrosh Cc: stgt-devel , linux-scsi , linux-kernel , FUJITA Tomonori , Mike Christie , James Bottomley , Douglas Gilbert In-Reply-To: <4C0CB071.8040805@panasas.com> References: <1275882640-5418-1-git-send-email-nab@linux-iscsi.org> <4C0CB071.8040805@panasas.com> Content-Type: text/plain Date: Mon, 07 Jun 2010 02:02:04 -0700 Message-Id: <1275901324.26888.56.camel@haakon2.linux-iscsi.org> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2010-06-07 at 11:40 +0300, Boaz Harrosh wrote: > On 06/07/2010 06:50 AM, Nicholas A. Bellinger wrote: > > From: Nicholas Bellinger > > > > This patch adds initial support for the block layer implementation of the sg v4 interface > > (BSG) -> STGT with a new struct backingstore_template bsg_bst sharing code with the > > original sg_bst. It adds for new function bs_bsg_cmd_submit() for incoming write I/O > > and bs_bsg_cmd_complete() for polling read I/O using include/linux/bsg.h:struct sg_io_v4. > > > > This patch also splits up bs_sg_open() to support both BSG and SG looking for the > > path "/dev/bsg" in bs_sg_open(), and getting max_queue using SG_GET_COMMAND_Q and > > calling SG_SET_RESERVED_SIZE (following the original bs_sg code in init_sg_device) > > > > Also chk_bsg_device() currently using a hardcoded 254 major as def for BSG does not > > appear in include/linux/major.h just yet.. > > > > So far this has been tested with STGT/iSCSI <-> BSG <-> TCM_Loop SPC-4 iSCSI Target > > Port emulation and is able to mkfs, fsck and mount a filesystem from a TCM/IBLOCK > > Linux LVM kernel level backstore > > > > Signed-off-by: Nicholas A. Bellinger > > --- > > usr/bs_sg.c | 178 +++++++++++++++++++++++++++++++++++++++++++++++++++--- > > usr/scsi_cmnd.h | 7 ++ > > 2 files changed, 175 insertions(+), 10 deletions(-) > > > > diff --git a/usr/bs_sg.c b/usr/bs_sg.c > > index 23676ef..d071714 100644 > > --- a/usr/bs_sg.c > > +++ b/usr/bs_sg.c > > + > > +static int bs_bsg_cmd_submit(struct scsi_cmd *cmd) > > +{ > > + struct scsi_lu *dev = cmd->dev; > > + int fd = dev->fd; > > + struct sg_io_v4 *io_hdr = &cmd->cmd_bsg_hdr; > > + int err = 0; > > + /* > > + * Following linux/include/linux/bsg.h > > + */ > > + /* [i] 'Q' to differentiate from v3 */ > > + io_hdr->guard = 'Q'; > > + io_hdr->protocol = BSG_PROTOCOL_SCSI; > > + io_hdr->subprotocol = BSG_SUB_PROTOCOL_SCSI_CMD; > > + io_hdr->request_len = cmd->scb_len; > > + io_hdr->request = (unsigned long )cmd->scb; > > + > > + if (scsi_get_data_dir(cmd) == DATA_WRITE) { > > Why the if? both sides are fully bidi just remove the ifs > and: OUT <= OUT, IN <= IN > Whoops, thanks for pointing this one out (again). Tested with unidirection commands and included into my local tgt.git/pass that I will send along to Tomo-san.. Btw, I still need to sort out BIDI support for TCM_Loop at some point in the not too distant future. What would be a good way to generate BIDI traffic into STGT or a local SCSI LLD..? Best, --nab