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=-8.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 B94D3C43387 for ; Fri, 14 Dec 2018 21:15:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D93BB208C2 for ; Fri, 14 Dec 2018 21:15:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544822138; bh=epMPbSPRuf7RitDOFQKrJneIizjhTYG75QIZawR1XFU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=TjIkhN7jRO1fSj9ELBb5TovafPeZUvHUYBqhSIKDvIQ9v0RpdU/s8/fGPuIdEHvz8 6TVc8oOisDXMbCKtLUxAei3xzOaub6K8051ZlgKtVHw7OyvQKOK8LDtRJksNrUMH6J lmFGQJaNPe5yDiB++WK7kmxXigYzGrt6791DoKAU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730925AbeLNVPh (ORCPT ); Fri, 14 Dec 2018 16:15:37 -0500 Received: from mail.kernel.org ([198.145.29.99]:58438 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730734AbeLNVPg (ORCPT ); Fri, 14 Dec 2018 16:15:36 -0500 Received: from localhost (unknown [69.71.4.100]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D398D2080F; Fri, 14 Dec 2018 21:15:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544822136; bh=epMPbSPRuf7RitDOFQKrJneIizjhTYG75QIZawR1XFU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=edjWIx2P68JwTuSuxHs9TnEhNSFkivUorcpjCFv/NctmF5/s1rm/61S7eekHcQRfg IeFWqIhBpeC5OrB131LImu6jD/4zBGiWoPo0Ab6nhpUhzs/2QGXAmuYJd/PyRl4ZrZ BIZ+ILeg3lX1bq9memQee2kSr/pyn+Wr1qdHPl8U= Date: Fri, 14 Dec 2018 15:15:33 -0600 From: Bjorn Helgaas To: Christoph Hellwig Cc: iommu@lists.linux-foundation.org, Linus Torvalds , Jesper Dangaard Brouer , Tariq Toukan , Ilias Apalodimas , Toke =?iso-8859-1?Q?H=F8iland-J=F8rgensen?= , Robin Murphy , Konrad Rzeszutek Wilk , Tony Luck , Fenghua Yu , Marek Szyprowski , Keith Busch , Jonathan Derrick , linux-pci@vger.kernel.org, linux-ia64@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 13/15] ACPI / scan: Refactor _CCA enforcement Message-ID: <20181214211533.GE20725@google.com> References: <20181207190720.18517-1-hch@lst.de> <20181207190720.18517-14-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181207190720.18517-14-hch@lst.de> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 07, 2018 at 11:07:18AM -0800, Christoph Hellwig wrote: > From: Robin Murphy > > Rather than checking the DMA attribute at each callsite, just pass it > through for acpi_dma_configure() to handle directly. That can then deal > with the relatively exceptional DEV_DMA_NOT_SUPPORTED case by explicitly > installing dummy DMA ops instead of just skipping setup entirely. This > will then free up the dev->dma_ops == NULL case for some valuable > fastpath optimisations. > > Signed-off-by: Robin Murphy > Signed-off-by: Christoph Hellwig > --- > drivers/acpi/scan.c | 5 +++++ > drivers/base/platform.c | 3 +-- > drivers/pci/pci-driver.c | 3 +-- Acked-by: Bjorn Helgaas # drivers/pci part > 3 files changed, 7 insertions(+), 4 deletions(-) > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index bd1c59fb0e17..b75ae34ed188 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -1456,6 +1456,11 @@ int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr) > const struct iommu_ops *iommu; > u64 dma_addr = 0, size = 0; > > + if (attr == DEV_DMA_NOT_SUPPORTED) { > + set_dma_ops(dev, &dma_dummy_ops); > + return 0; > + } > + > iort_dma_setup(dev, &dma_addr, &size); > > iommu = iort_iommu_configure(dev); > diff --git a/drivers/base/platform.c b/drivers/base/platform.c > index eae841935a45..c1ddf191711e 100644 > --- a/drivers/base/platform.c > +++ b/drivers/base/platform.c > @@ -1138,8 +1138,7 @@ int platform_dma_configure(struct device *dev) > ret = of_dma_configure(dev, dev->of_node, true); > } else if (has_acpi_companion(dev)) { > attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode)); > - if (attr != DEV_DMA_NOT_SUPPORTED) > - ret = acpi_dma_configure(dev, attr); > + ret = acpi_dma_configure(dev, attr); > } > > return ret; > diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c > index bef17c3fca67..1b58e058b13f 100644 > --- a/drivers/pci/pci-driver.c > +++ b/drivers/pci/pci-driver.c > @@ -1602,8 +1602,7 @@ static int pci_dma_configure(struct device *dev) > struct acpi_device *adev = to_acpi_device_node(bridge->fwnode); > enum dev_dma_attr attr = acpi_get_dma_attr(adev); > > - if (attr != DEV_DMA_NOT_SUPPORTED) > - ret = acpi_dma_configure(dev, attr); > + ret = acpi_dma_configure(dev, acpi_get_dma_attr(adev)); > } > > pci_put_host_bridge_device(bridge); > -- > 2.19.1 >