Date:   Mon, 6 Dec 2021 08:40:33 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Lu Baolu <baolu.lu@linux.intel.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Joerg Roedel <joro@8bytes.org>,
        Alex Williamson <alex.williamson@redhat.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Christoph Hellwig <hch@infradead.org>,
        Kevin Tian <kevin.tian@intel.com>,
        Ashok Raj <ashok.raj@intel.com>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Dan Williams <dan.j.williams@intel.com>, rafael@kernel.org,
        Diana Craciun <diana.craciun@oss.nxp.com>,
        Cornelia Huck <cohuck@redhat.com>,
        Eric Auger <eric.auger@redhat.com>,
        Liu Yi L <yi.l.liu@intel.com>,
        Jacob jun Pan <jacob.jun.pan@intel.com>,
        Chaitanya Kulkarni <kch@nvidia.com>,
        Stuart Yoder <stuyoder@gmail.com>,
        Laurentiu Tudor <laurentiu.tudor@nxp.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        Jonathan Hunter <jonathanh@nvidia.com>,
        Li Yang <leoyang.li@nxp.com>,
        Dmitry Osipenko <digetx@gmail.com>,
        iommu@lists.linux-foundation.org, linux-pci@vger.kernel.org,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 18/18] drm/tegra: Use the iommu dma_owner mechanism
Message-ID: <20211206124033.GY4670@nvidia.com>
References: <20211206015903.88687-1-baolu.lu@linux.intel.com>
 <20211206015903.88687-19-baolu.lu@linux.intel.com>
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20211206015903.88687-19-baolu.lu@linux.intel.com>
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Xtf88+u64J9uwBCLMNyLPICnPyQZz2MYd9YGlP2LClP8vVabAyCDKWwryLES?=
 =?us-ascii?Q?Zar3FDT+OmbmUuckTZl96JskFKaSkeNuELVsY6qf/e1nx/CefQ4ipdapd9t5?=
 =?us-ascii?Q?x0h+zaWyyVSqi8wrMS20oY//XsyR+H9LZ6z5eDmLt0uz5e3C9xCQ4VhBExm2?=
 =?us-ascii?Q?fMRVLxiP2IUHnOilfp1zaACGTp5mgdw9LTCczl9Y9DuYPpkQ20XS7ktPbb49?=
 =?us-ascii?Q?IWJpFe/cRIl2P/x3yj9OJqG52uNJPvPqZ/I2vvqs+s+bWRYgdZd6RCB5NVOz?=
 =?us-ascii?Q?PCPQROa5He4hlNk0SvcsmYDygs9jYkJTgXmObI0xtvv85PBs8CD0cIasQI2q?=
 =?us-ascii?Q?SlRuBABWijenvrGMgTIhW51P5Jw7M1N5jkSWvTj4qxS7vdAx0eRT2M5ua+Vi?=
 =?us-ascii?Q?q0vnugpWOdOQrOpmsG8rMeDRpqhb9ESv0hrrMYPqmXIs+nC+uz113RmeExmW?=
 =?us-ascii?Q?irwE0hDEDscvyRonOFUrbrixmdXrCWnEDBPO5fMVFJv+amCeY8i8+2Wmut07?=
 =?us-ascii?Q?aVQ749U3jyyVNjA2UfcQNKGat5xfpIUpx7j100yZHcq6AWlfpjO0TPmI/dED?=
 =?us-ascii?Q?jufF2QISWijQuS2Ksj59viVG1ZuhXwP4r92TXKrcVvqou2hOFcBEmVuWvxq0?=
 =?us-ascii?Q?WAZBsfBuDhBgguMHOMfkLyPdNJ0+22RTPiwE3o14E9rHCq30Dbm65H9eqekv?=
 =?us-ascii?Q?f2e0x2Q9Wt3ekUiD0V9i1+WY/TAxVJv8vl1vvuuQ74mcXi9cHrE6BbPCeGl9?=
 =?us-ascii?Q?+BR6ASuJE4vJRCCCo0QwqsvUTc0rwqmcIZtx1YPIW+OZwRwU5gIuklpSoC14?=
 =?us-ascii?Q?7NB/nb8M7grf5k5Xv3sm3ddWJkqkV3JIDUlav+/rI2UUmKkfp/JsHutaBTV2?=
 =?us-ascii?Q?UTRJFp19lVzHzbk8y9/HQRgJ7daoPfnasM9Y+TqavaXuCqlifYPwAJphH5mI?=
 =?us-ascii?Q?8pmiZdWqDutwFZZDROrG51hCP6kCIaZUgcYSjlbBOfbh9Z0suzVIkqTK08eN?=
 =?us-ascii?Q?Vg3mLr+jd256qLRjFHqNI1WK6wobqLbnyu0IJ6+/rjUrn/8697tvvAsvHLf9?=
 =?us-ascii?Q?ntHqA/0krbztHbJQ5jK+9iliFSw3EC2YJ+sdM8MHSLtvN638cOruova7HE0o?=
 =?us-ascii?Q?rMicjoPqyk1n84rdXHpK96DOKI7mXDSCjNqRVk9C3SoZDZspsZ1QScYRQbo1?=
 =?us-ascii?Q?jUw5Gb009K7fcefHFevlhSSpSK7oSV1ZTrPVT14W+h8z/veA7C+UNJ6nC3QP?=
 =?us-ascii?Q?8Xn21GsunGEMHRYdMwHK6jJdnDVtulRnSQlF7qoXkpkNPm9olfbbzO05JVba?=
 =?us-ascii?Q?8ADvvy8BCezxcggRFQX0dhhCZQ1ohj1K5hed4l2ZX3bvTxxczAjKUOf4wuX2?=
 =?us-ascii?Q?w9aQO3Cm+lcBA7dZkxSqGDZXcZNiI36bQ2KfHERazJ4T0eHH4ISRNhWOrD/r?=
 =?us-ascii?Q?QFIS9KPNTGy9utBqnbJYD6OGsAX1eSAc3Oty1piA+CZRcAFUW1IHa0FVklS+?=
 =?us-ascii?Q?FZrceF4fjUcyip/Oyfs7pCqxvmzZOet7xtVC8asOqdUeQPfdTrDO8uDbtBqJ?=
 =?us-ascii?Q?aT3F/P1XJRso5/bevsA=3D?=
X-OriginatorOrg: Nvidia.com
X-MS-Exchange-CrossTenant-Network-Message-Id: b83efe14-9e30-4d8e-3948-08d9b8b59952
X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB5506.namprd12.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Dec 2021 12:40:35.4747
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: zQdfiAiojas7K0sEEZLFVaH4niwMHP4PeU4P1I2Ds2nkjnmkWx+JDEPJdiuKfULC
X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5253
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Mon, Dec 06, 2021 at 09:59:03AM +0800, Lu Baolu wrote:

> @@ -941,48 +944,44 @@ int host1x_client_iommu_attach(struct host1x_client *client)
>  	 * not the shared IOMMU domain, don't try to attach it to a different
>  	 * domain. This allows using the IOMMU-backed DMA API.
>  	 */
> -	if (domain && domain != tegra->domain)
> +	client->group = NULL;
> +	if (!client->dev->iommu_group || (domain && domain != tegra->domain))
> +		return iommu_device_set_dma_owner(client->dev,
> +						  DMA_OWNER_DMA_API, NULL);
> +
> +	if (!tegra->domain)
>  		return 0;

This if should be removed completely now

Jason