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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B4DCBC43142 for ; Wed, 27 Jun 2018 12:49:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6D650208B9 for ; Wed, 27 Jun 2018 12:49:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6D650208B9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753654AbeF0MtD (ORCPT ); Wed, 27 Jun 2018 08:49:03 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:39290 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752545AbeF0MtA (ORCPT ); Wed, 27 Jun 2018 08:49:00 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6F2B74021CC1; Wed, 27 Jun 2018 12:48:59 +0000 (UTC) Received: from localhost (ovpn-12-44.pek2.redhat.com [10.72.12.44]) by smtp.corp.redhat.com (Postfix) with ESMTP id EEB2B1117658; Wed, 27 Jun 2018 12:48:47 +0000 (UTC) From: Ming Lei To: Jens Axboe , Christoph Hellwig , Kent Overstreet Cc: David Sterba , Huang Ying , Mike Snitzer , linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Theodore Ts'o , "Darrick J . Wong" , Coly Li , Filipe Manana , Randy Dunlap , Ming Lei Subject: [PATCH V7 15/24] fs/buffer.c: use bvec iterator to truncate the bio Date: Wed, 27 Jun 2018 20:45:39 +0800 Message-Id: <20180627124548.3456-16-ming.lei@redhat.com> In-Reply-To: <20180627124548.3456-1-ming.lei@redhat.com> References: <20180627124548.3456-1-ming.lei@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Wed, 27 Jun 2018 12:48:59 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Wed, 27 Jun 2018 12:48:59 +0000 (UTC) for IP:'10.11.54.3' DOMAIN:'int-mx03.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'ming.lei@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Once multipage bvec is enabled, the last bvec may include more than one page, this patch use bvec_last_segment() to truncate the bio. Signed-off-by: Ming Lei --- fs/buffer.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/buffer.c b/fs/buffer.c index cabc045f483d..0660b7813315 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -3021,7 +3021,10 @@ void guard_bio_eod(int op, struct bio *bio) /* ..and clear the end of the buffer for reads */ if (op == REQ_OP_READ) { - zero_user(bvec->bv_page, bvec->bv_offset + bvec->bv_len, + struct bio_vec bv; + + bvec_last_segment(bvec, &bv); + zero_user(bv.bv_page, bv.bv_offset + bv.bv_len, truncated_bytes); } } -- 2.9.5