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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 43FFFC76186 for ; Wed, 24 Jul 2019 03:57:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 21C7521670 for ; Wed, 24 Jul 2019 03:57:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726547AbfGXD5r (ORCPT ); Tue, 23 Jul 2019 23:57:47 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:2745 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725855AbfGXD5r (ORCPT ); Tue, 23 Jul 2019 23:57:47 -0400 Received: from DGGEMS411-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id CEE496E40C58B4D5EB37; Wed, 24 Jul 2019 11:57:45 +0800 (CST) Received: from localhost.localdomain (10.67.212.75) by DGGEMS411-HUB.china.huawei.com (10.3.19.211) with Microsoft SMTP Server id 14.3.439.0; Wed, 24 Jul 2019 11:57:39 +0800 From: Zhou Wang To: , CC: , , Zhou Wang Subject: [PATCH resend v2] lib: scatterlist: Fix to support no mapped sg Date: Wed, 24 Jul 2019 11:54:23 +0800 Message-ID: <1563940463-95597-1-git-send-email-wangzhou1@hisilicon.com> X-Mailer: git-send-email 2.8.1 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.67.212.75] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In function sg_split, the second sg_calculate_split will return -EINVAL when in_mapped_nents is 0. Indeed there is no need to do second sg_calculate_split and sg_split_mapped when in_mapped_nents is 0, as in_mapped_nents indicates no mapped entry in original sgl. Signed-off-by: Zhou Wang Acked-by: Robert Jarzmik --- v2: Just add Acked-by from Robert. lib/sg_split.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/lib/sg_split.c b/lib/sg_split.c index 9982c63..60a0bab 100644 --- a/lib/sg_split.c +++ b/lib/sg_split.c @@ -176,11 +176,13 @@ int sg_split(struct scatterlist *in, const int in_mapped_nents, * The order of these 3 calls is important and should be kept. */ sg_split_phys(splitters, nb_splits); - ret = sg_calculate_split(in, in_mapped_nents, nb_splits, skip, - split_sizes, splitters, true); - if (ret < 0) - goto err; - sg_split_mapped(splitters, nb_splits); + if (in_mapped_nents) { + ret = sg_calculate_split(in, in_mapped_nents, nb_splits, skip, + split_sizes, splitters, true); + if (ret < 0) + goto err; + sg_split_mapped(splitters, nb_splits); + } for (i = 0; i < nb_splits; i++) { out[i] = splitters[i].out_sg; -- 2.8.1