From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: MIME-Version: 1.0 In-Reply-To: <1450464730.10450.14.camel@hpe.com> References: <1450393200-6802-1-git-send-email-toshi.kani@hpe.com> <1450427687.11503.14.camel@kernel.org> <1450451737.20148.121.camel@hpe.com> <1450464730.10450.14.camel@hpe.com> Date: Fri, 18 Dec 2015 14:23:21 -0800 Message-ID: Subject: Re: [PATCH] BTT: Change nd_btt_arena_is_valid() to verify UUID From: Dan Williams Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org To: Toshi Kani Cc: Vishal Verma , "linux-kernel@vger.kernel.org" , micah.parrish@hpe.com, "linux-nvdimm@lists.01.org" List-ID: On Fri, Dec 18, 2015 at 10:52 AM, Toshi Kani wrote: > On Fri, 2015-12-18 at 09:54 -0800, Dan Williams wrote: >> On Fri, Dec 18, 2015 at 7:15 AM, Toshi Kani wrote: >> > On Fri, 2015-12-18 at 01:34 -0700, Vishal Verma wrote: >> > > Also, I wonder if this problem is solved by using libndctl to manage >> > > BTTs. >> > >> > I have not tested with libndctl yet, but I think our bind/unbind >> > scripts do the same procedures. >> >> We loop through all combinations of sector size in our unit test. If >> you want to change the sector size the expectation is that the >> namespace is destroyed and fully re-created, especially due to the >> fact that changing sector size invalidates all data on the namespace. >> >> See: https://github.com/pmem/ndctl/blob/master/lib/test-libndctl.c > > The parent_uuid is not set on our NVDIMM-N systems. I do not see 'uuid' > file under sysfs 'namespaceX.X' per namespace_visible(), either. This > concept of creating/destroying a namespace is a bit foreign to us since > we've never needed to do. Can you elaborate how it's supposed to work for > NVDIMM-N? > Ugh, yes. An oversight on my part, let me give this some thought. Whatever we decide, I want the libndctl api to be identical for the two cases. I expect the simplest option is to have ndctl_namespace_disable_invalidate() destroy the btt-info block in the NVDIMM-N case. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965216AbbLRWXX (ORCPT ); Fri, 18 Dec 2015 17:23:23 -0500 Received: from mail-yk0-f181.google.com ([209.85.160.181]:33374 "EHLO mail-yk0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932486AbbLRWXV (ORCPT ); Fri, 18 Dec 2015 17:23:21 -0500 MIME-Version: 1.0 In-Reply-To: <1450464730.10450.14.camel@hpe.com> References: <1450393200-6802-1-git-send-email-toshi.kani@hpe.com> <1450427687.11503.14.camel@kernel.org> <1450451737.20148.121.camel@hpe.com> <1450464730.10450.14.camel@hpe.com> Date: Fri, 18 Dec 2015 14:23:21 -0800 Message-ID: Subject: Re: [PATCH] BTT: Change nd_btt_arena_is_valid() to verify UUID From: Dan Williams To: Toshi Kani Cc: Vishal Verma , "linux-kernel@vger.kernel.org" , micah.parrish@hpe.com, "linux-nvdimm@lists.01.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 18, 2015 at 10:52 AM, Toshi Kani wrote: > On Fri, 2015-12-18 at 09:54 -0800, Dan Williams wrote: >> On Fri, Dec 18, 2015 at 7:15 AM, Toshi Kani wrote: >> > On Fri, 2015-12-18 at 01:34 -0700, Vishal Verma wrote: >> > > Also, I wonder if this problem is solved by using libndctl to manage >> > > BTTs. >> > >> > I have not tested with libndctl yet, but I think our bind/unbind >> > scripts do the same procedures. >> >> We loop through all combinations of sector size in our unit test. If >> you want to change the sector size the expectation is that the >> namespace is destroyed and fully re-created, especially due to the >> fact that changing sector size invalidates all data on the namespace. >> >> See: https://github.com/pmem/ndctl/blob/master/lib/test-libndctl.c > > The parent_uuid is not set on our NVDIMM-N systems. I do not see 'uuid' > file under sysfs 'namespaceX.X' per namespace_visible(), either. This > concept of creating/destroying a namespace is a bit foreign to us since > we've never needed to do. Can you elaborate how it's supposed to work for > NVDIMM-N? > Ugh, yes. An oversight on my part, let me give this some thought. Whatever we decide, I want the libndctl api to be identical for the two cases. I expect the simplest option is to have ndctl_namespace_disable_invalidate() destroy the btt-info block in the NVDIMM-N case.