From mboxrd@z Thu Jan 1 00:00:00 1970 From: Douglas Gilbert Subject: Re: [PATCH 6/6] scsi_debug: add ability to enable clustering Date: Sun, 05 Jan 2014 20:14:23 -0500 Message-ID: <52CA036F.4030404@interlog.com> References: <1388964792-3546-1-git-send-email-akinobu.mita@gmail.com> <1388964792-3546-7-git-send-email-akinobu.mita@gmail.com> Reply-To: dgilbert@interlog.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.infotech.no ([82.134.31.41]:36929 "EHLO smtp.infotech.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752090AbaAFBOp (ORCPT ); Sun, 5 Jan 2014 20:14:45 -0500 In-Reply-To: <1388964792-3546-7-git-send-email-akinobu.mita@gmail.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Akinobu Mita , linux-scsi@vger.kernel.org Cc: "James E.J. Bottomley" , "Martin K. Petersen" On 14-01-05 06:33 PM, Akinobu Mita wrote: > This adds a module parameter to enable clustering. > > Without enabling clustering support, the transfer length for read and > write scsi commands is limited upto 8MB when page size is 4KB and > sg_tablesize is 2048 (= SCSI_MAX_SG_CHAIN_SEGMENTS). I would like to > test commands with more than that transfer length. > > Signed-off-by: Akinobu Mita > Cc: "James E.J. Bottomley" > Cc: Douglas Gilbert > Cc: "Martin K. Petersen" > Cc: linux-scsi@vger.kernel.org > --- > drivers/scsi/scsi_debug.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c > index aca70c1..9297688d 100644 > --- a/drivers/scsi/scsi_debug.c > +++ b/drivers/scsi/scsi_debug.c > @@ -196,6 +196,7 @@ static unsigned int scsi_debug_unmap_max_blocks = DEF_UNMAP_MAX_BLOCKS; > static unsigned int scsi_debug_unmap_max_desc = DEF_UNMAP_MAX_DESC; > static unsigned int scsi_debug_write_same_length = DEF_WRITESAME_LENGTH; > static bool scsi_debug_removable = DEF_REMOVABLE; > +static bool scsi_debug_clustering; > > static int scsi_debug_cmnd_count = 0; > > @@ -2787,6 +2788,7 @@ module_param_named(opts, scsi_debug_opts, int, S_IRUGO | S_IWUSR); > module_param_named(physblk_exp, scsi_debug_physblk_exp, int, S_IRUGO); > module_param_named(ptype, scsi_debug_ptype, int, S_IRUGO | S_IWUSR); > module_param_named(removable, scsi_debug_removable, bool, S_IRUGO | S_IWUSR); > +module_param_named(clustering, scsi_debug_clustering, bool, S_IRUGO); Umm, clustering is writeable, so: S_IRUGO | S_IWUSR > module_param_named(scsi_level, scsi_debug_scsi_level, int, S_IRUGO); > module_param_named(sector_size, scsi_debug_sector_size, int, S_IRUGO); > module_param_named(unmap_alignment, scsi_debug_unmap_alignment, int, S_IRUGO); > @@ -3953,6 +3955,8 @@ static int sdebug_driver_probe(struct device * dev) > sdbg_host = to_sdebug_host(dev); > > sdebug_driver_template.can_queue = scsi_debug_max_queue; > + if (scsi_debug_clustering) > + sdebug_driver_template.use_clustering = ENABLE_CLUSTERING; > hpnt = scsi_host_alloc(&sdebug_driver_template, sizeof(sdbg_host)); > if (NULL == hpnt) { > printk(KERN_ERR "%s: scsi_register failed\n", __func__); > And please document this extra parameter for modinfo. Something like: MODULE_PARM_DESC(clustering, "when set enables larger transfers (def=0)"); placed in alphabetical order. Doug Gilbert