From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD92CC433EF for ; Wed, 2 Mar 2022 17:07:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234082AbiCBRIF (ORCPT ); Wed, 2 Mar 2022 12:08:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243646AbiCBRH4 (ORCPT ); Wed, 2 Mar 2022 12:07:56 -0500 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 031CCCCC67; Wed, 2 Mar 2022 09:07:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1646240833; x=1677776833; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=ZDYri7lCowU3GJr6M0z1hSFUZr0wdNpx1kXCi+W+DLY=; b=Os+MBOe+zBd+r0D/K/KAGx+2Dg3b4+APvOdW5x+44PKA066Hr2E36fV4 qKGhmyXwKkF9fVTuuCfwsIJEBO8Rhg1s9rRGqilmGjrk2CL+kmtuVu5EL ElqxFQGKvaCGDrGCSKjyPMyNtZmDORfkWwfw3gfhDyZMZpv8jcS+kKrDh Iw6Pyd/COesp2Ho8R23sZBY/TQviaYWA+3Dte6XDihkINI+3F1vQ7a9KF 24oc+vBk+snZhFKRsQ6h9JZt0klDLnD03znsJPC1+Hq3gfgSyIujRPZOg VWnV5ryIc44iioFwrJQv3Ir5qZ0CIiBOBRVZjhjcYNdS7gqmNqyDbNdTU w==; X-IronPort-AV: E=McAfee;i="6200,9189,10274"; a="253183409" X-IronPort-AV: E=Sophos;i="5.90,149,1643702400"; d="scan'208";a="253183409" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Mar 2022 09:04:52 -0800 X-IronPort-AV: E=Sophos;i="5.90,149,1643702400"; d="scan'208";a="493606916" Received: from akshatak-mobl.amr.corp.intel.com (HELO localhost) ([10.212.41.96]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Mar 2022 09:04:51 -0800 Date: Wed, 2 Mar 2022 09:04:50 -0800 From: Ira Weiny To: Christoph Hellwig Cc: Jens Axboe , Chris Zankel , Max Filippov , Justin Sanders , Philipp Reisner , Lars Ellenberg , Denis Efremov , Minchan Kim , Nitin Gupta , Coly Li , Dan Williams , Vishal Verma , linux-xtensa@linux-xtensa.org, linux-block@vger.kernel.org, drbd-dev@lists.linbit.com, linux-bcache@vger.kernel.org, nvdimm@lists.linux.dev Subject: Re: [PATCH 06/10] nvdimm-btt: use bvec_kmap_local in btt_rw_integrity Message-ID: References: <20220222155156.597597-1-hch@lst.de> <20220222155156.597597-7-hch@lst.de> <20220301122042.GB3405@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220301122042.GB3405@lst.de> Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Tue, Mar 01, 2022 at 01:20:42PM +0100, Christoph Hellwig wrote: > On Mon, Feb 28, 2022 at 07:59:06PM -0800, Ira Weiny wrote: > > On Tue, Feb 22, 2022 at 04:51:52PM +0100, Christoph Hellwig wrote: > > > Using local kmaps slightly reduces the chances to stray writes, and > > > the bvec interface cleans up the code a little bit. > > > > > > Signed-off-by: Christoph Hellwig > > > --- > > > drivers/nvdimm/btt.c | 10 ++++------ > > > 1 file changed, 4 insertions(+), 6 deletions(-) > > > > > > diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c > > > index cbd994f7f1fe6..9613e54c7a675 100644 > > > --- a/drivers/nvdimm/btt.c > > > +++ b/drivers/nvdimm/btt.c > > > @@ -1163,17 +1163,15 @@ static int btt_rw_integrity(struct btt *btt, struct bio_integrity_payload *bip, > > > */ > > > > > > cur_len = min(len, bv.bv_len); > > > - mem = kmap_atomic(bv.bv_page); > > > + mem = bvec_kmap_local(&bv); > > > if (rw) > > > - ret = arena_write_bytes(arena, meta_nsoff, > > > - mem + bv.bv_offset, cur_len, > > > + ret = arena_write_bytes(arena, meta_nsoff, mem, cur_len, > > > > Why drop bv.bv_offset here and below? > > Because bvec_kmap_local includes bv_offset in the pointer that it > returns. Ah I missed that. Thanks, Ira