From patchwork Mon Dec 6 01:58:49 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Baolu Lu X-Patchwork-Id: 12657505 X-Patchwork-Delegate: bhelgaas@google.com 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4DFA9C433EF for ; Mon, 6 Dec 2021 01:59:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232111AbhLFCDT (ORCPT ); Sun, 5 Dec 2021 21:03:19 -0500 Received: from mga17.intel.com ([192.55.52.151]:52404 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232090AbhLFCDT (ORCPT ); Sun, 5 Dec 2021 21:03:19 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10189"; a="217916240" X-IronPort-AV: E=Sophos;i="5.87,290,1631602800"; d="scan'208";a="217916240" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Dec 2021 17:59:51 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.87,290,1631602800"; d="scan'208";a="514542009" Received: from allen-box.sh.intel.com ([10.239.159.118]) by orsmga008.jf.intel.com with ESMTP; 05 Dec 2021 17:59:44 -0800 From: Lu Baolu To: Greg Kroah-Hartman , Joerg Roedel , Alex Williamson , Bjorn Helgaas , Jason Gunthorpe , Christoph Hellwig , Kevin Tian , Ashok Raj Cc: Will Deacon , Robin Murphy , Dan Williams , rafael@kernel.org, Diana Craciun , Cornelia Huck , Eric Auger , Liu Yi L , Jacob jun Pan , Chaitanya Kulkarni , Stuart Yoder , Laurentiu Tudor , Thierry Reding , David Airlie , Daniel Vetter , Jonathan Hunter , Li Yang , Dmitry Osipenko , iommu@lists.linux-foundation.org, linux-pci@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Lu Baolu Subject: [PATCH v3 04/18] driver core: platform: Add driver dma ownership management Date: Mon, 6 Dec 2021 09:58:49 +0800 Message-Id: <20211206015903.88687-5-baolu.lu@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211206015903.88687-1-baolu.lu@linux.intel.com> References: <20211206015903.88687-1-baolu.lu@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Multiple platform devices may be placed in the same IOMMU group because they cannot be isolated from each other. These devices must either be entirely under kernel control or userspace control, never a mixture. This checks and sets DMA ownership during driver binding, and release the ownership during driver unbinding. Driver may set a new flag (suppress_auto_claim_dma_owner) to disable auto claiming DMA_OWNER_DMA_API ownership in the binding process. For instance, the userspace framework drivers (vfio etc.) which need to manually claim DMA_OWNER_PRIVATE_DOMAIN_USER when assigning a device to userspace. Signed-off-by: Lu Baolu --- include/linux/platform_device.h | 1 + drivers/base/platform.c | 30 +++++++++++++++++++++++++++++- 2 files changed, 30 insertions(+), 1 deletion(-) diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 4381c34af7e0..f3926be7582f 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -210,6 +210,7 @@ struct platform_driver { struct device_driver driver; const struct platform_device_id *id_table; bool prevent_deferred_probe; + bool suppress_auto_claim_dma_owner; }; #define to_platform_driver(drv) (container_of((drv), struct platform_driver, \ diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 125d708c0eb3..032b9f20b468 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -30,6 +30,7 @@ #include #include #include +#include #include "base.h" #include "power/power.h" @@ -1464,6 +1465,32 @@ int firmware_dma_configure(struct device *dev) return ret; } +static int platform_dma_configure(struct device *dev) +{ + struct platform_driver *drv = to_platform_driver(dev->driver); + int ret; + + if (!drv->suppress_auto_claim_dma_owner) { + ret = iommu_device_set_dma_owner(dev, DMA_OWNER_DMA_API, NULL); + if (ret) + return ret; + } + + ret = firmware_dma_configure(dev); + if (ret && !drv->suppress_auto_claim_dma_owner) + iommu_device_release_dma_owner(dev, DMA_OWNER_DMA_API); + + return ret; +} + +static void platform_dma_cleanup(struct device *dev) +{ + struct platform_driver *drv = to_platform_driver(dev->driver); + + if (!drv->suppress_auto_claim_dma_owner) + iommu_device_release_dma_owner(dev, DMA_OWNER_DMA_API); +} + static const struct dev_pm_ops platform_dev_pm_ops = { SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend, pm_generic_runtime_resume, NULL) USE_PLATFORM_PM_SLEEP_OPS @@ -1477,7 +1504,8 @@ struct bus_type platform_bus_type = { .probe = platform_probe, .remove = platform_remove, .shutdown = platform_shutdown, - .dma_configure = firmware_dma_configure, + .dma_configure = platform_dma_configure, + .dma_cleanup = platform_dma_cleanup, .pm = &platform_dev_pm_ops, }; EXPORT_SYMBOL_GPL(platform_bus_type);