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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 9159DC54E8B for ; Tue, 12 May 2020 12:18:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F13120661 for ; Tue, 12 May 2020 12:18:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729735AbgELMSv (ORCPT ); Tue, 12 May 2020 08:18:51 -0400 Received: from verein.lst.de ([213.95.11.211]:40918 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729437AbgELMSv (ORCPT ); Tue, 12 May 2020 08:18:51 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id 543D768BEB; Tue, 12 May 2020 14:18:49 +0200 (CEST) Date: Tue, 12 May 2020 14:18:49 +0200 From: Christoph Hellwig To: Marek Szyprowski Cc: dri-devel@lists.freedesktop.org, iommu@lists.linux-foundation.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, Christoph Hellwig , Robin Murphy , Bartlomiej Zolnierkiewicz , linux-arm-kernel@lists.infradead.org, David Airlie , Daniel Vetter , Joerg Roedel Subject: Re: [PATCH v4 03/38] iommu: add generic helper for mapping sgtable objects Message-ID: <20200512121849.GC20393@lst.de> References: <20200512085710.14688-1-m.szyprowski@samsung.com> <20200512090058.14910-1-m.szyprowski@samsung.com> <20200512090058.14910-3-m.szyprowski@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200512090058.14910-3-m.szyprowski@samsung.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 12, 2020 at 11:00:23AM +0200, Marek Szyprowski wrote: > struct sg_table is a common structure used for describing a memory > buffer. It consists of a scatterlist with memory pages and DMA addresses > (sgl entry), as well as the number of scatterlist entries: CPU pages > (orig_nents entry) and DMA mapped pages (nents entry). > > It turned out that it was a common mistake to misuse nents and orig_nents > entries, calling mapping functions with a wrong number of entries. > > To avoid such issues, lets introduce a common wrapper operating directly > on the struct sg_table objects, which take care of the proper use of > the nents and orig_nents entries. > > Signed-off-by: Marek Szyprowski Looks good, Reviewed-by: Christoph Hellwig 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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 68639C54E4A for ; Tue, 12 May 2020 12:18:55 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 45812206A5 for ; Tue, 12 May 2020 12:18:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 45812206A5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 21D0F882C7; Tue, 12 May 2020 12:18:55 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id rX6WBsZDDOUw; Tue, 12 May 2020 12:18:53 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by whitealder.osuosl.org (Postfix) with ESMTP id B40778829A; Tue, 12 May 2020 12:18:53 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id AE32AC0178; Tue, 12 May 2020 12:18:53 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id B557BC016F for ; Tue, 12 May 2020 12:18:52 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id A439787255 for ; Tue, 12 May 2020 12:18:52 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id zr-wNDrpLZL6 for ; Tue, 12 May 2020 12:18:51 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by fraxinus.osuosl.org (Postfix) with ESMTPS id 8302A86CD7 for ; Tue, 12 May 2020 12:18:51 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 543D768BEB; Tue, 12 May 2020 14:18:49 +0200 (CEST) Date: Tue, 12 May 2020 14:18:49 +0200 From: Christoph Hellwig To: Marek Szyprowski Subject: Re: [PATCH v4 03/38] iommu: add generic helper for mapping sgtable objects Message-ID: <20200512121849.GC20393@lst.de> References: <20200512085710.14688-1-m.szyprowski@samsung.com> <20200512090058.14910-1-m.szyprowski@samsung.com> <20200512090058.14910-3-m.szyprowski@samsung.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200512090058.14910-3-m.szyprowski@samsung.com> User-Agent: Mutt/1.5.17 (2007-11-01) Cc: Bartlomiej Zolnierkiewicz , David Airlie , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, iommu@lists.linux-foundation.org, Daniel Vetter , Robin Murphy , Christoph Hellwig , linux-arm-kernel@lists.infradead.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Tue, May 12, 2020 at 11:00:23AM +0200, Marek Szyprowski wrote: > struct sg_table is a common structure used for describing a memory > buffer. It consists of a scatterlist with memory pages and DMA addresses > (sgl entry), as well as the number of scatterlist entries: CPU pages > (orig_nents entry) and DMA mapped pages (nents entry). > > It turned out that it was a common mistake to misuse nents and orig_nents > entries, calling mapping functions with a wrong number of entries. > > To avoid such issues, lets introduce a common wrapper operating directly > on the struct sg_table objects, which take care of the proper use of > the nents and orig_nents entries. > > Signed-off-by: Marek Szyprowski Looks good, Reviewed-by: Christoph Hellwig _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu 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=-5.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 5A8C5C54E8B for ; Tue, 12 May 2020 12:18:55 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 271AF206A3 for ; Tue, 12 May 2020 12:18:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="mJCjJfu+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 271AF206A3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=R8dXQFaF6zFcxP9/VCjnHl9FH00P6dXQtpcjNDViK6g=; b=mJCjJfu+vxcY7n xgH+ft87l0ub8yJx00B8eYUCC1SJdvDU1FNhTbrTTcYzflLpoNJBBb7/5Awq1HTqXvH5u0SIAHD+z 6lFcx081k93SgCnNinU1NCwcABjX4hxfMAKgy4zw7rb33pljZ9fangVuPId8zmyZVPmtiHV6L5J1H co5xt0b4xG/Bn+NuB6UeWrmZlwAy19J7yFiEiAt5tLD12p1lECIoOtoB5uy3WHDbZ7oOpg7Qd4B0a fENjly4z1KOwEynFUfUdIjuGkQ6lNC1XxDfVF1j1AK4eHTJdywmb/8zxp0k6jxIq9eb3qYhbqSUBM VCkI8lbwG/51sxiVvRFA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jYTs6-0002PQ-Dn; Tue, 12 May 2020 12:18:54 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jYTs3-0002O1-7x for linux-arm-kernel@lists.infradead.org; Tue, 12 May 2020 12:18:52 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 543D768BEB; Tue, 12 May 2020 14:18:49 +0200 (CEST) Date: Tue, 12 May 2020 14:18:49 +0200 From: Christoph Hellwig To: Marek Szyprowski Subject: Re: [PATCH v4 03/38] iommu: add generic helper for mapping sgtable objects Message-ID: <20200512121849.GC20393@lst.de> References: <20200512085710.14688-1-m.szyprowski@samsung.com> <20200512090058.14910-1-m.szyprowski@samsung.com> <20200512090058.14910-3-m.szyprowski@samsung.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200512090058.14910-3-m.szyprowski@samsung.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200512_051851_447101_FD3F6E61 X-CRM114-Status: GOOD ( 10.56 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Bartlomiej Zolnierkiewicz , David Airlie , Joerg Roedel , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, iommu@lists.linux-foundation.org, Daniel Vetter , Robin Murphy , Christoph Hellwig , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, May 12, 2020 at 11:00:23AM +0200, Marek Szyprowski wrote: > struct sg_table is a common structure used for describing a memory > buffer. It consists of a scatterlist with memory pages and DMA addresses > (sgl entry), as well as the number of scatterlist entries: CPU pages > (orig_nents entry) and DMA mapped pages (nents entry). > > It turned out that it was a common mistake to misuse nents and orig_nents > entries, calling mapping functions with a wrong number of entries. > > To avoid such issues, lets introduce a common wrapper operating directly > on the struct sg_table objects, which take care of the proper use of > the nents and orig_nents entries. > > Signed-off-by: Marek Szyprowski Looks good, Reviewed-by: Christoph Hellwig _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel