From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id B09172125ADEC for ; Thu, 16 May 2019 11:57:53 -0700 (PDT) Date: Thu, 16 May 2019 14:57:32 -0400 From: Mike Snitzer Subject: Re: dax: Arrange for dax_supported check to span multiple devices Message-ID: <20190516185732.GA27796@redhat.com> References: <155789172402.748145.11853718580748830476.stgit@dwillia2-desk3.amr.corp.intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <155789172402.748145.11853718580748830476.stgit@dwillia2-desk3.amr.corp.intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" To: Dan Williams Cc: Jan Kara , linux-nvdimm@lists.01.org, Heiko Carstens , linux-kernel@vger.kernel.org, Matthew Wilcox , linux-fsdevel@vger.kernel.org, dm-devel@redhat.com, stable@vger.kernel.org, Martin Schwidefsky List-ID: On Tue, May 14 2019 at 11:48pm -0400, Dan Williams wrote: > Pankaj reports that starting with commit ad428cdb525a "dax: Check the > end of the block-device capacity with dax_direct_access()" device-mapper > no longer allows dax operation. This results from the stricter checks in > __bdev_dax_supported() that validate that the start and end of a > block-device map to the same 'pagemap' instance. > > Teach the dax-core and device-mapper to validate the 'pagemap' on a > per-target basis. This is accomplished by refactoring the > bdev_dax_supported() internals into generic_fsdax_supported() which > takes a sector range to validate. Consequently generic_fsdax_supported() > is suitable to be used in a device-mapper ->iterate_devices() callback. > A new ->dax_supported() operation is added to allow composite devices to > split and route upper-level bdev_dax_supported() requests. > > Fixes: ad428cdb525a ("dax: Check the end of the block-device...") > Cc: > Cc: Jan Kara > Cc: Ira Weiny > Cc: Dave Jiang > Cc: Mike Snitzer > Cc: Keith Busch > Cc: Matthew Wilcox > Cc: Vishal Verma > Cc: Heiko Carstens > Cc: Martin Schwidefsky > Reported-by: Pankaj Gupta > Signed-off-by: Dan Williams > --- > Hi Mike, > > Another day another new dax operation to allow device-mapper to better > scope dax operations. > > Let me know if the device-mapper changes look sane. This passes a new > unit test that indeed fails on current mainline. > > https://github.com/pmem/ndctl/blob/device-mapper-pending/test/dm.sh > > drivers/dax/super.c | 88 +++++++++++++++++++++++++++--------------- > drivers/md/dm-table.c | 17 +++++--- > drivers/md/dm.c | 20 ++++++++++ > drivers/md/dm.h | 1 > drivers/nvdimm/pmem.c | 1 > drivers/s390/block/dcssblk.c | 1 > include/linux/dax.h | 19 +++++++++ > 7 files changed, 110 insertions(+), 37 deletions(-) > ... > diff --git a/drivers/md/dm.h b/drivers/md/dm.h > index 2d539b82ec08..e5e240bfa2d0 100644 > --- a/drivers/md/dm.h > +++ b/drivers/md/dm.h > @@ -78,6 +78,7 @@ void dm_unlock_md_type(struct mapped_device *md); > void dm_set_md_type(struct mapped_device *md, enum dm_queue_mode type); > enum dm_queue_mode dm_get_md_type(struct mapped_device *md); > struct target_type *dm_get_immutable_target_type(struct mapped_device *md); > +bool dm_table_supports_dax(struct dm_table *t, int blocksize); > > int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t); > I'd prefer to have dm_table_supports_dax come just after dm_table_get_md_mempools in the preceding dm_table section of dm.h (just above this mapped_device section you extended). But other than that nit, patch looks great on a DM level: Reviewed-by: Mike Snitzer _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm