From patchwork Wed Jun 27 12:45:39 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 10491515 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 7227B602B3 for ; Wed, 27 Jun 2018 12:52:26 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6482328E03 for ; Wed, 27 Jun 2018 12:52:26 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 62C3A28E79; Wed, 27 Jun 2018 12:52:26 +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=unavailable 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 1B12A28E03 for ; Wed, 27 Jun 2018 12:52:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753144AbeF0MtC (ORCPT ); Wed, 27 Jun 2018 08:49:02 -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-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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); } }