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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0B5ECC433F5 for ; Mon, 18 Oct 2021 06:26:47 +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 BBA4460F9D for ; Mon, 18 Oct 2021 06:26:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org BBA4460F9D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=mediatek.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=XfatoMCDcDg3Ah2P9xcC+/uYDUroE8oNdM87Wtcvd2I=; b=v4n5qSWyKRVA9Z 7KG7dG2+bG73u3gjhZMLiPgStTWAjqZKaJ+Ww8vh248DLLxGRJrQLUGMG3Du1Oh3Npd1LhxXL2Zw4 ey127QZZ/GwZbxm8fyX0cfI8MB1/1WJGw/ywUjLW1HD5lnSuX5+9l0PHg3Frn0Cnvhp3ZMrpgX5IR Ob9dZmhB9yYNEzqOL7qPvwTm/RaEGHwE2yIC22wPkm85ecR3gOLtUoYbg7354ECK2WKKcj8k3djHh hHKdiuIdAFgsQV4BCtcymwujYKY4Ql5aTy6dDn+ZSybogMIMsJM0nTT/+uaapRMJGSBMQnMcyNvFK kXmVGAnwy8UB7sBugV+g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mcM5E-00EJvs-Kf; Mon, 18 Oct 2021 06:25:16 +0000 Received: from mailgw02.mediatek.com ([216.200.240.185]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mcM56-00EJuH-PT; Mon, 18 Oct 2021 06:25:12 +0000 X-UUID: ea8bd886cdff41e4af9c8e49f4fd7151-20211017 X-UUID: ea8bd886cdff41e4af9c8e49f4fd7151-20211017 Received: from mtkcas67.mediatek.inc [(172.29.193.45)] by mailgw02.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1123718799; Sun, 17 Oct 2021 23:25:06 -0700 Received: from mtkmbs10n1.mediatek.inc (172.21.101.34) by MTKMBS62N1.mediatek.inc (172.29.193.41) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Sun, 17 Oct 2021 23:25:05 -0700 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs10n1.mediatek.inc (172.21.101.34) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.15; Mon, 18 Oct 2021 14:25:03 +0800 Received: from mszswglt01.gcn.mediatek.inc (10.16.20.20) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Mon, 18 Oct 2021 14:25:02 +0800 From: To: CC: , , , , , , , , , , , , , , , , , , , Guangming Cao Subject: Re: [PATCH] dma-buf: Add support for mapping buffers with DMA attributes Date: Mon, 18 Oct 2021 14:25:04 +0800 Message-ID: <20211018062504.116652-1-guangming.cao@mediatek.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: References: MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211017_232508_875610_9DCF641D X-CRM114-Status: GOOD ( 32.31 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Guangming Cao On Tue, 2021-08-31 at 14:47 +0200, Daniel Vetter wrote: > On Mon, Aug 30, 2021 at 10:39:11AM +0800, guangming.cao@mediatek.com > wrote: > > From: Guangming Cao > > > > When mapping the memory represented by a dma-buf into a device's > > address space, it might be desireable to map the memory with > > certain DMA attributes. Thus, introduce the dma_mapping_attrs > > field in the dma_buf_attachment structure so that when > > the memory is mapped with dma_buf_map_attachment, it is mapped > > with the desired DMA attributes. > > > > Signed-off-by: Isaac J. Manjarres > > Signed-off-by: Sandeep Patil > > Signed-off-by: Guangming Cao > > Can you pls include the code that's going to use this here too? > > At a glance all the attributes you might want to set are supposed to > be > under the control of the exporter, not the importer. > -Daniel > Hi Daniel, Sorry for the late. Currently I couldn't upload the coding going to use this part because of some miscellaneous reasons. Just as I said in commit message, for dma_heap, users can't skip cache sync or other opetrations when map iova[dma_buf_map_attachment] by fill (struct dma_buf_attachment).dma_map_attrs, it's not dma_map_attrs expected(link: https://github.com/torvalds/linux/blob/master/Documentation/core-api/dma-attributes.rst#dma_attr_skip_cpu_sync ). Correspondingly, if they use dma_buf to map iova[dma_buf_map_attrs], they will not meet this issue. So, I think it's a design flaw for dma_heap. BRs! Guangming > > --- > > drivers/dma-buf/heaps/cma_heap.c | 6 ++++-- > > drivers/dma-buf/heaps/system_heap.c | 6 ++++-- > > include/linux/dma-buf.h | 3 +++ > > 3 files changed, 11 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma- > > buf/heaps/cma_heap.c > > index 0c05b79870f9..2c9feb3bfc3e 100644 > > --- a/drivers/dma-buf/heaps/cma_heap.c > > +++ b/drivers/dma-buf/heaps/cma_heap.c > > @@ -99,9 +99,10 @@ static struct sg_table > > *cma_heap_map_dma_buf(struct dma_buf_attachment *attachme > > { > > struct dma_heap_attachment *a = attachment->priv; > > struct sg_table *table = &a->table; > > + int attrs = attachment->dma_map_attrs; > > int ret; > > > > - ret = dma_map_sgtable(attachment->dev, table, direction, 0); > > + ret = dma_map_sgtable(attachment->dev, table, direction, > > attrs); > > if (ret) > > return ERR_PTR(-ENOMEM); > > a->mapped = true; > > @@ -113,9 +114,10 @@ static void cma_heap_unmap_dma_buf(struct > > dma_buf_attachment *attachment, > > enum dma_data_direction direction) > > { > > struct dma_heap_attachment *a = attachment->priv; > > + int attrs = attachment->dma_map_attrs; > > > > a->mapped = false; > > - dma_unmap_sgtable(attachment->dev, table, direction, 0); > > + dma_unmap_sgtable(attachment->dev, table, direction, attrs); > > } > > > > static int cma_heap_dma_buf_begin_cpu_access(struct dma_buf > > *dmabuf, > > diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma- > > buf/heaps/system_heap.c > > index 23a7e74ef966..fc7b1e02988e 100644 > > --- a/drivers/dma-buf/heaps/system_heap.c > > +++ b/drivers/dma-buf/heaps/system_heap.c > > @@ -130,9 +130,10 @@ static struct sg_table > > *system_heap_map_dma_buf(struct dma_buf_attachment *attac > > { > > struct dma_heap_attachment *a = attachment->priv; > > struct sg_table *table = a->table; > > + int attrs = attachment->dma_map_attrs; > > int ret; > > > > - ret = dma_map_sgtable(attachment->dev, table, direction, 0); > > + ret = dma_map_sgtable(attachment->dev, table, direction, > > attrs); > > if (ret) > > return ERR_PTR(ret); > > > > @@ -145,9 +146,10 @@ static void system_heap_unmap_dma_buf(struct > > dma_buf_attachment *attachment, > > enum dma_data_direction > > direction) > > { > > struct dma_heap_attachment *a = attachment->priv; > > + int attrs = attachment->dma_map_attrs; > > > > a->mapped = false; > > - dma_unmap_sgtable(attachment->dev, table, direction, 0); > > + dma_unmap_sgtable(attachment->dev, table, direction, attrs); > > } > > > > static int system_heap_dma_buf_begin_cpu_access(struct dma_buf > > *dmabuf, > > diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h > > index efdc56b9d95f..4d650731766e 100644 > > --- a/include/linux/dma-buf.h > > +++ b/include/linux/dma-buf.h > > @@ -379,6 +379,8 @@ struct dma_buf_attach_ops { > > * @importer_ops: importer operations for this attachment, if > > provided > > * dma_buf_map/unmap_attachment() must be called with the dma_resv > > lock held. > > * @importer_priv: importer specific attachment data. > > + * @dma_map_attrs: DMA attributes to be used when the exporter > > maps the buffer > > + * through dma_buf_map_attachment. > > * > > * This structure holds the attachment information between the > > dma_buf buffer > > * and its user device(s). The list contains one attachment struct > > per device > > @@ -399,6 +401,7 @@ struct dma_buf_attachment { > > const struct dma_buf_attach_ops *importer_ops; > > void *importer_priv; > > void *priv; > > + unsigned long dma_map_attrs; > > }; > > > > /** > > -- > > 2.17.1 > > > > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel