From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: [PATCH 7/7] scsi_dh: attach to hardware handler from dm-mpath Date: Wed, 21 May 2008 08:18:26 +0200 Message-ID: <4833BEB2.1070305@suse.de> References: <20080514144338.714F910B5DF@craiglockhart-ipmi.suse.de> <1210819801.21974.266.camel@chandra-ubuntu> <482C0676.9070004@suse.de> <1210964001.21974.351.camel@chandra-ubuntu> <483154B0.7020500@suse.de> <1211221247.21974.382.camel@chandra-ubuntu> <4832C706.5040202@suse.de> <1211309554.21974.427.camel@chandra-ubuntu> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1211309554.21974.427.camel@chandra-ubuntu> Sender: linux-scsi-owner@vger.kernel.org To: sekharan@us.ibm.com Cc: James Bottomley , linux-scsi , dm-devel List-Id: dm-devel.ids Chandra Seetharaman wrote: > Hi Hannes, >=20 > Now I see why you want this change in dm-multipath. I think I agree w= ith > these changes. >=20 Ah. good. > But, it brings another question: what does dh_state provide ? Help to > user to see which hardware handler a device is attached to ? >=20 And allowing to attach to a different hardware handler. Not everyone is running multipathing, but might be interested in the having the device handler nevertheless. > I thought more about the scsi_dh_detach function (in the context of m= y > earlier comment), adding it would require more housekeeping to associ= ate > one-to-one mapping between attach and detach. We can leave it the sam= e > way as the module will be detached when the device disappear eventual= ly. >=20 Why? You can detach with dh_state, too; just do an echo detach > /sys/block/sdX/device/dh_state and the hardware handler will detach. So no additional attribute is required. Cheers, Hannes --=20 Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg GF: Markus Rex, HRB 16746 (AG N=FCrnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html