From patchwork Tue Aug 8 08:45:11 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 9887161 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 3648760384 for ; Tue, 8 Aug 2017 09:01:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 28B0A2864C for ; Tue, 8 Aug 2017 09:01:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1D55D287D2; Tue, 8 Aug 2017 09:01:39 +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=-6.9 required=2.0 tests=BAYES_00,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 A42FC2864C for ; Tue, 8 Aug 2017 09:01:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752562AbdHHIsW (ORCPT ); Tue, 8 Aug 2017 04:48:22 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46378 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752062AbdHHIsT (ORCPT ); Tue, 8 Aug 2017 04:48:19 -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 6874E769E0; Tue, 8 Aug 2017 08:48:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 6874E769E0 Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=ming.lei@redhat.com Received: from localhost (ovpn-12-24.pek2.redhat.com [10.72.12.24]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7F7CA5C7C4; Tue, 8 Aug 2017 08:48:11 +0000 (UTC) From: Ming Lei To: Jens Axboe , Christoph Hellwig , Huang Ying , Andrew Morton , Alexander Viro Cc: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Ming Lei , Chris Mason , Josef Bacik , David Sterba , linux-btrfs@vger.kernel.org, Liu Bo Subject: [PATCH v3 12/49] btrfs: avoid to access bvec table directly for a cloned bio Date: Tue, 8 Aug 2017 16:45:11 +0800 Message-Id: <20170808084548.18963-13-ming.lei@redhat.com> In-Reply-To: <20170808084548.18963-1-ming.lei@redhat.com> References: <20170808084548.18963-1-ming.lei@redhat.com> 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 [10.5.110.27]); Tue, 08 Aug 2017 08:48:19 +0000 (UTC) Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Commit 17347cec15f919901c90(Btrfs: change how we iterate bios in endio) mentioned that for dio the submitted bio may be fast cloned, we can't access the bvec table directly for a cloned bio, so use bio_get_first_bvec() to retrieve the 1st bvec. Cc: Chris Mason Cc: Josef Bacik Cc: David Sterba Cc: linux-btrfs@vger.kernel.org Cc: Liu Bo Reviewed-by: Liu Bo Acked: David Sterba Signed-off-by: Ming Lei --- fs/btrfs/inode.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 95c212037095..5cf320ee7ea0 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -7993,6 +7993,7 @@ static int dio_read_error(struct inode *inode, struct bio *failed_bio, int read_mode = 0; int segs; int ret; + struct bio_vec bvec; BUG_ON(bio_op(failed_bio) == REQ_OP_WRITE); @@ -8008,8 +8009,9 @@ static int dio_read_error(struct inode *inode, struct bio *failed_bio, } segs = bio_segments(failed_bio); + bio_get_first_bvec(failed_bio, &bvec); if (segs > 1 || - (failed_bio->bi_io_vec->bv_len > btrfs_inode_sectorsize(inode))) + (bvec.bv_len > btrfs_inode_sectorsize(inode))) read_mode |= REQ_FAILFAST_DEV; isector = start - btrfs_io_bio(failed_bio)->logical;