From patchwork Wed May 15 19:26:57 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vivek Goyal X-Patchwork-Id: 10945157 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4486013AD for ; Wed, 15 May 2019 19:28:22 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 343B72842D for ; Wed, 15 May 2019 19:28:22 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2858A28555; Wed, 15 May 2019 19:28:22 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CBC502842D for ; Wed, 15 May 2019 19:28:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727879AbfEOT2I (ORCPT ); Wed, 15 May 2019 15:28:08 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49680 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727725AbfEOT1g (ORCPT ); Wed, 15 May 2019 15:27:36 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D49807E9F9; Wed, 15 May 2019 19:27:35 +0000 (UTC) Received: from horse.redhat.com (unknown [10.18.25.29]) by smtp.corp.redhat.com (Postfix) with ESMTP id EC45B9CCA; Wed, 15 May 2019 19:27:32 +0000 (UTC) Received: by horse.redhat.com (Postfix, from userid 10451) id B0D40225480; Wed, 15 May 2019 15:27:29 -0400 (EDT) From: Vivek Goyal To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-nvdimm@lists.01.org Cc: vgoyal@redhat.com, miklos@szeredi.hu, stefanha@redhat.com, dgilbert@redhat.com, swhiteho@redhat.com Subject: [PATCH v2 12/30] dax: remove block device dependencies Date: Wed, 15 May 2019 15:26:57 -0400 Message-Id: <20190515192715.18000-13-vgoyal@redhat.com> In-Reply-To: <20190515192715.18000-1-vgoyal@redhat.com> References: <20190515192715.18000-1-vgoyal@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Wed, 15 May 2019 19:27:35 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Stefan Hajnoczi Although struct dax_device itself is not tied to a block device, some DAX code assumes there is a block device. Make block devices optional by allowing bdev to be NULL in commonly used DAX APIs. When there is no block device: * Skip the partition offset calculation in bdev_dax_pgoff() * Skip the blkdev_issue_zeroout() optimization Note that more block device assumptions remain but I haven't reach those code paths yet. Signed-off-by: Stefan Hajnoczi --- drivers/dax/super.c | 3 ++- fs/dax.c | 7 ++++++- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/dax/super.c b/drivers/dax/super.c index 0a339b85133e..cb44ec663991 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -53,7 +53,8 @@ EXPORT_SYMBOL_GPL(dax_read_unlock); int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size, pgoff_t *pgoff) { - phys_addr_t phys_off = (get_start_sect(bdev) + sector) * 512; + sector_t start_sect = bdev ? get_start_sect(bdev) : 0; + phys_addr_t phys_off = (start_sect + sector) * 512; if (pgoff) *pgoff = PHYS_PFN(phys_off); diff --git a/fs/dax.c b/fs/dax.c index e5e54da1715f..815bc32fd967 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -1042,7 +1042,12 @@ static vm_fault_t dax_load_hole(struct xa_state *xas, static bool dax_range_is_aligned(struct block_device *bdev, unsigned int offset, unsigned int length) { - unsigned short sector_size = bdev_logical_block_size(bdev); + unsigned short sector_size; + + if (!bdev) + return false; + + sector_size = bdev_logical_block_size(bdev); if (!IS_ALIGNED(offset, sector_size)) return false;