From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: [PATCH 3/3] dm mpath: add support for using previously attached scsi_dh Date: Tue, 08 May 2012 08:22:27 +0200 Message-ID: <4FA8BBA3.3030705@suse.de> References: <1336447147-3830-1-git-send-email-snitzer@redhat.com> <1336447147-3830-2-git-send-email-snitzer@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1336447147-3830-2-git-send-email-snitzer@redhat.com> Sender: linux-scsi-owner@vger.kernel.org To: Mike Snitzer Cc: dm-devel@redhat.com, agk@redhat.com, babu.moger@netapp.com, sekharan@us.ibm.com, linux-scsi@vger.kernel.org List-Id: dm-devel.ids On 05/08/2012 05:19 AM, Mike Snitzer wrote: > Use the previously attached scsi_dh if "default" is provided as the > hardware handler name (the new 'use_default_hw_handler' flag is set i= n > the multipath structure). >=20 > Leverage scsi_dh_attach's ability to increment the scsi_dh's referenc= e > count if the same scsi_dh name is provided when attaching -- currentl= y > attached scsi_dh name is determined with scsi_dh_attached_handler_nam= e. >=20 Not sure it that's the correct way. Using 'default' as the hardware handler name has the drawback that the original information (ie the original hardware handler name) is lost. So if there is no 'default', eg if the kernel module hasn't been loaded, we wouldn't know which hardware handler to load. I'd rather have a feature 'default_hw_handler' which then could be passed into the kernel module. With that we would retain both, the original implementation and the default case. 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: J. Hawn, J. Guild, F. Imend=F6rffer, 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