From patchwork Fri Jul 23 17:50:08 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 12396661 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 F12D8C41537 for ; Fri, 23 Jul 2021 17:50:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D90AB60F02 for ; Fri, 23 Jul 2021 17:50:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232035AbhGWRJt (ORCPT ); Fri, 23 Jul 2021 13:09:49 -0400 Received: from ale.deltatee.com ([204.191.154.188]:50566 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231126AbhGWRJr (ORCPT ); Fri, 23 Jul 2021 13:09:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltatee.com; s=20200525; h=Subject:MIME-Version:References:In-Reply-To: Message-Id:Date:Cc:To:From:content-disposition; bh=HKCVUstwA/z3wuW2EGad6Fa2PQLjmM0RyJDS41E8gEg=; b=ceE3xNa5zKwrpv+KSzmE7LfjqN 0q/StfTaFLC89OIPsL5+enoCQ8wyl6/6i4jsEFiR43MEKekW1TRVGs6gbFQAw05b52z+Gg/B/HERs 9OhcoIjeIB26sAHv5+uTd3D/NbWNNXUPnOUr95+mHUB34EmPY7Fko/92+5UiQVxjDeY5a2hCXho37 WUkvAUx9LUDaBn28taATIaM4Whds0u2lS0PSsUSwfkqXp0M+8yje3Gmj75OuBqwto3/1QVzP9VFof dxz4o8gHrETaFZyTg9X6dGaLxMEevxwctrUYwYEcmWkRnf+9VN8ernNXHxdpFxwYPEua/aErYGkeC VaCk22FA==; Received: from cgy1-donard.priv.deltatee.com ([172.16.1.31]) by ale.deltatee.com with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1m6zJQ-0005Li-JV; Fri, 23 Jul 2021 11:50:17 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.92) (envelope-from ) id 1m6zJN-0005rW-Is; Fri, 23 Jul 2021 11:50:13 -0600 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, iommu@lists.linux-foundation.org, linux-parisc@vger.kernel.org, xen-devel@lists.xenproject.org Cc: Christoph Hellwig , Marek Szyprowski , Robin Murphy , Stephen Bates , Martin Oliveira , Logan Gunthorpe Date: Fri, 23 Jul 2021 11:50:08 -0600 Message-Id: <20210723175008.22410-22-logang@deltatee.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210723175008.22410-1-logang@deltatee.com> References: <20210723175008.22410-1-logang@deltatee.com> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-parisc@vger.kernel.org, xen-devel@lists.xenproject.org, hch@lst.de, m.szyprowski@samsung.com, robin.murphy@arm.com, sbates@raithlin.com, martin.oliveira@eideticom.com, logang@deltatee.com X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [PATCH v2 21/21] dma-mapping: Disallow .map_sg operations from returning zero on error X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org Now that all the .map_sg operations have been converted to returning proper error codes, drop the code to handle a zero return value, add a warning if a zero is returned and update the comment for the map_sg operation. Signed-off-by: Logan Gunthorpe --- kernel/dma/mapping.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index b8dc8b1cb402..86a8a421344a 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -194,6 +194,9 @@ static int __dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, else ents = ops->map_sg(dev, sg, nents, dir, attrs); + if (WARN_ON_ONCE(ents == 0)) + return -EIO; + if (ents > 0) debug_dma_map_sg(dev, sg, nents, ents, dir); @@ -259,9 +262,7 @@ int dma_map_sgtable(struct device *dev, struct sg_table *sgt, int nents; nents = __dma_map_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs); - if (nents == 0) - return -EIO; - else if (nents < 0) { + if (nents < 0) { if (WARN_ON_ONCE(nents != -EINVAL && nents != -ENOMEM && nents != -EIO)) return -EIO;