Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751987AbbFZBJB (ORCPT ); Thu, 25 Jun 2015 21:09:01 -0400 Received: from mail-ie0-f179.google.com ([209.85.223.179]:36618 "EHLO mail-ie0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751195AbbFZBIt (ORCPT ); Thu, 25 Jun 2015 21:08:49 -0400 MIME-Version: 1.0 In-Reply-To: <1435280115.11808.374.camel@misato.fc.hp.com> References: <20150625090554.40066.69562.stgit@dwillia2-desk3.jf.intel.com> <20150625093738.40066.88750.stgit@dwillia2-desk3.jf.intel.com> <1435254317.11808.327.camel@misato.fc.hp.com> <1435257283.13411.4.camel@intel.com> <1435269103.11808.349.camel@misato.fc.hp.com> <1435270287.11808.352.camel@misato.fc.hp.com> <1435272910.11808.356.camel@misato.fc.hp.com> <1435275750.18090.5.camel@intel.com> <1435280115.11808.374.camel@misato.fc.hp.com> Date: Thu, 25 Jun 2015 18:08:48 -0700 X-Google-Sender-Auth: DpYkwaCHteDRnL-YpoNhZeDRxP8 Message-ID: Subject: Re: [PATCH v2 15/17] libnvdimm: Set numa_node to NVDIMM devices From: Dan Williams To: Toshi Kani Cc: "axboe@kernel.dk" , "linux-nvdimm@lists.01.org" , "linux-kernel@vger.kernel.org" , "mingo@kernel.org" , "linux-acpi@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "hch@lst.de" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3752 Lines: 91 On Thu, Jun 25, 2015 at 5:55 PM, Toshi Kani wrote: > On Thu, 2015-06-25 at 23:42 +0000, Williams, Dan J wrote: >> On Thu, 2015-06-25 at 16:55 -0600, Toshi Kani wrote: >> > On Thu, 2015-06-25 at 15:34 -0700, Dan Williams wrote: >> > > On Thu, Jun 25, 2015 at 3:11 PM, Toshi Kani wrote: >> > > > On Thu, 2015-06-25 at 15:00 -0700, Dan Williams wrote: >> > > > Yes, I see no problem with bound BTTs and their device files. So, how >> > > > do we bind BTT with this new version? >> > > > >> > > >> > > # cd /sys/bus/nd/devices >> > > # uuidgen > btt6/uuid >> > > # echo 4096 > btt6/sector_size >> > > # echo namespace6.0 > btt6/namespace >> > > # echo namespace6.0 > ../drivers/nd_pmem/unbind >> > > # echo btt6 > ../drivers/nd_pmem/bind >> > > >> > > After reboot, when the system sees namespace6.0 again it will notice >> > > the btt instance and attach bttX instead. The net effect is that now >> > > you'll only ever have /dev/pmem6 or /dev/pmem6s, never both at the >> > > same time that was a side effect of the stacking approach. >> > > >> > > I'll post the patch that updates libndctl and the unit tests shortly >> > >> > Maybe I am missing something, but I am getting errors on my system. (I >> > used btt0 since there is no btt6.) >> > >> > # cat bind.sh >> > set -x >> > cd /sys/bus/nd/devices >> > uuidgen > btt0/uuid >> > echo 4096 > btt0/sector_size >> > echo namespace0.0 > btt0/namespace >> > echo namespace0.0 > ../drivers/nd_pmem/unbind >> > echo btt0 > ../drivers/nd_pmem/bind >> > >> > # sh bind.sh >> > + cd /sys/bus/nd/devices >> > + uuidgen >> > + echo 4096 >> > + echo namespace0.0 >> > bind.sh: line 6: echo: write error: Device or resource busy >> > + echo namespace0.0 >> > bind.sh: line 7: echo: write error: No such device >> > + echo btt0 >> > bind.sh: line 8: echo: write error: No such device >> > >> > # dmesg >> > : >> > [12513.839162] nd btt0: uuid_store: result: 0 wrote: >> > b32cd195-9aae-4c54-a5ac-49adb50a8a98 >> > [12513.880286] nd btt0: sector_size_store: result: 0 wrote: 4096 >> > [12513.909494] nd btt0: namespace0.0 already claimed >> > [12513.933364] nd btt0: namespace_store: result: -16 wrote: namespace0.0 >> > [12513.966808] ndbus0: nd_pmem.probe(btt0) = -19 >> > >> >> So this turned out to be a perfect example of why we might want to have >> the region-id in the btt device name just like namespaces, because btt0 >> was actually bound to namespace4.0 on Toshi's system. The following >> update, that I will fold in to the series, fixes this. Note that the >> association of btt id to to namespace is still non-deterministic. I.e. >> btt0.1 could be assigned as the btt for namespace0.0, but at least when >> looking at /sys/bus/nd/devices it will be clear which btts belong to >> which regions. >> >> # ls /sys/bus/nd/devices >> btt0.0 btt3.0 btt6.0 namespace2.0 namespace5.0 nmem1 nmem4 region2 region5 >> btt1.0 btt4.0 namespace0.0 namespace3.0 namespace6.0 nmem2 region0 region3 region6 >> btt2.0 btt5.0 namespace1.0 namespace4.0 nmem0 nmem3 region1 region4 > > Yes, this works nicely. :-) > > Now, how do I unbind BTT? I did the following as a guess, but BTT got > reattached again before I have a chance to delete the metadata, which I > need /dev/pmemN. > > NUM=1 > cd /sys/bus/nd/devices > echo "" > btt${NUM}.1/namespace > echo btt${NUM}.1 > ../drivers/nd_pmem/unbind echo 1 > namespace${NUM}.0/force_raw > echo namespace${NUM}.0 > ../drivers/nd_pmem/bind > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/