Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Dongli Zhang <dongli.zhang@oracle.com>
To:     iommu@lists.linux-foundation.org, xen-devel@lists.xenproject.org,
        x86@kernel.org, linuxppc-dev@lists.ozlabs.org,
        virtualization@lists.linux-foundation.org
Cc:     linux-kernel@vger.kernel.org, hch@infradead.org,
        m.szyprowski@samsung.com, jgross@suse.com, tglx@linutronix.de,
        mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com,
        sstabellini@kernel.org, mpe@ellerman.id.au, konrad.wilk@oracle.com,
        mst@redhat.com, jasowang@redhat.com, joe.jin@oracle.com
Subject: [PATCH RFC v1 6/7] virtio: use io_tlb_high_mem if it is active
Date:   Wed,  8 Jun 2022 17:55:52 -0700
Message-Id: <20220609005553.30954-7-dongli.zhang@oracle.com>
In-Reply-To: <20220609005553.30954-1-dongli.zhang@oracle.com>
References: <20220609005553.30954-1-dongli.zhang@oracle.com>
Content-Type: text/plain
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?OfE2mbk/d4ZjDpuW/3GlLsKLX4ZjEXJM2MW+bi0sMEAMQibcTwBr55VTBgcs?=
 =?us-ascii?Q?rS4Zdi4HO1HAhH4w7Yfm/Bq9ptWzNT81nqTPzVVTezeq3sc1WF90tEhqm/ew?=
 =?us-ascii?Q?xYE63zrApzRmTdqOtUb5cb0XjmMlhnBypX8zjlesPPGE5HzF8ecq89svW4RM?=
 =?us-ascii?Q?CUec66iyLeV+NA8fFf6eedhfnfcqwGimehfRxmjEQLWJaNsVvgMSbpuMHshp?=
 =?us-ascii?Q?Yiz+xTdyS1rv1DJCDPrfVcUtpnh/2yzmtMRKnA89HFng1iUmUxifk7E/gZzu?=
 =?us-ascii?Q?P2FagjQIbybNykoETQb4eKVQ8cyp6fOlu5enCExy5NtyaHodrJD9X2lav75l?=
 =?us-ascii?Q?944ZO5RfiiYcxlLaxxEGgfYCcOtnrYJs6H30b3q4Q+sExUSmbamRRl/2opB6?=
 =?us-ascii?Q?xP+Wea46t3Sz84QwQEi9y7QbgMrPE7ij5Wl4xMPZaFTiJiBb9AOfFQxiDjcP?=
 =?us-ascii?Q?aZJVuPZtPoAcIAfYxxlHswP8v145SpvnMUIWAxFo9ZR9U4WUTGH/fyZSqoc+?=
 =?us-ascii?Q?FRyx/0Xx/hQ5A8FBHH5XDJSpjgO5AgnEwzqAR1Bkc7d5d3xbADLuZwsXrTry?=
 =?us-ascii?Q?zo9wUdl3BvnyujTifsp8kdpmmV3adWsK0Wxvo8s3tcJHoxiRuXder16hWLqL?=
 =?us-ascii?Q?MI8XA8gmb0qsJvMdMMGmpiQGhmQv0uMR6M7W6qRiobFMS2x07H8vAumE//ST?=
 =?us-ascii?Q?+p04L0Z6/cK90jHduUzjDJfKw9WNfVS6YoC2ZoY8aHeUqMMpCKDmn+Bno1UW?=
 =?us-ascii?Q?tdK/hRbAXEQgOGs3VkfI/faPBiK9k77fyZ7N5Y5MCENxSPQA1qJlYMghAEMS?=
 =?us-ascii?Q?JiTxmufmPZoZCscb/I1wtszrZ3ClNSSGLUxKdIfxi4/6HyAyJ92LUSYui4C4?=
 =?us-ascii?Q?qtK1ID8U2XSs1ZVr7U7+XlwcpJgwdOd8opBaGNUC6NSipN5tiwRROKmb8+8T?=
 =?us-ascii?Q?vtEW83CbqnkTld3teVvmE9ah5mo98zVbcAGv4VF8jvQlV95jGNV4LdD0gdKG?=
 =?us-ascii?Q?k59TF1smnkFdWnt7uz+bNuOQkfcM+fFmREj9wdXt5AWM3UAwsv6mfVj0lUzo?=
 =?us-ascii?Q?98iLpw7PpAeH/QiuDMYVZK/e558FZcz3E9a+heD5ZoLN9dcJ+RWGqkXXsgEc?=
 =?us-ascii?Q?yq1c9aC0d4pHYV807nCgDw5WoLc+ElIE35AUyLuIkEQezbeMGy9cxnBSITVH?=
 =?us-ascii?Q?sizuYr5e6U1/ZYj5UIM8uo/YDoLVVy3f8FIlPcU8HefuYNvLr8TR0fPdXI4w?=
 =?us-ascii?Q?mLPkWGwHJt/3so8a39OCstGINse96PovSjkF2pwOfTCoYRAEeygoEVgmKv2k?=
 =?us-ascii?Q?d+3RP4qRqNJ/O2mgPAfdxLXIQXSdZt2HxhskT9tmpKN9IPE9nFaX3nixy7IE?=
 =?us-ascii?Q?QY69H7GNZupwMTlt3sQhEYiSfVPZj9bEyQzno8VCvKDaODqGjfOVtIj4e2y3?=
 =?us-ascii?Q?9yhWm/gVOlS1P+8X/RWt55ybWhBFsp6/bzFLvIGj3ieUfLrbzsjAJmYspR3v?=
 =?us-ascii?Q?cBYexcunEJw78dyU3vb+Z2L5DQXTzeEekYqGlhEwmVEBjIHuC2M8ULCJ7eut?=
 =?us-ascii?Q?u31PdLiMoX11iJ7hu5/wQfTYH8j46Iz+sDr67BHkZ+PjronOs6S7fpToYIPw?=
 =?us-ascii?Q?JloM9YYr0bxLYebQMqrSG+ACXMmxfaaWiTPPi5W3D7DoM7O+Kw/AZvkJxU+Y?=
 =?us-ascii?Q?dABYbuZL5llypjK3qk0PPvUegEZeJJd79r8wKGKZdVAPdAHPKxERyv9AEwER?=
 =?us-ascii?Q?yjcm2YFoZlxeTQlkEridJYLjIBaji9I=3D?=
X-OriginatorOrg: oracle.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 68ae0a81-e49a-4ce9-8c6f-08da49b333e8
X-MS-Exchange-CrossTenant-AuthSource: BYAPR10MB2663.namprd10.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Jun 2022 00:58:44.6448
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: U8tCX3jI++97fFdKG73OhS/Bsx2w1/ExREvbONLR5S+W7c4dp+9Sa8GIf27TNsZEKgUGIUtn9y4XcoULFtUbpA==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR10MB2488
X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.517,18.0.874
 definitions=2022-06-08_04:2022-06-07,2022-06-08 signatures=0
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 mlxlogscore=999
 adultscore=0 bulkscore=0 mlxscore=0 suspectscore=0 malwarescore=0
 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1
 engine=8.12.0-2204290000 definitions=main-2206090001
X-Proofpoint-GUID: pu1VdrVJqh7XmXDZttnPoU3K2016-zGU
X-Proofpoint-ORIG-GUID: pu1VdrVJqh7XmXDZttnPoU3K2016-zGU
X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00,DKIM_SIGNED,
        DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW,
        RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE
        autolearn=ham autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

When the swiotlb is enforced (e.g., when amd sev is involved), the virito
driver will not be able to use 4+ GB memory. Therefore, the virtio driver
uses 'io_tlb_high_mem' as swiotlb.

Cc: Konrad Wilk <konrad.wilk@oracle.com>
Cc: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
---
 drivers/virtio/virtio.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index ef04a96942bf..d9ebe3940e2d 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -5,6 +5,8 @@
 #include <linux/module.h>
 #include <linux/idr.h>
 #include <linux/of.h>
+#include <linux/swiotlb.h>
+#include <linux/dma-mapping.h>
 #include <uapi/linux/virtio_ids.h>
 
 /* Unique numbering for virtio devices. */
@@ -241,6 +243,12 @@ static int virtio_dev_probe(struct device *_d)
 	u64 device_features;
 	u64 driver_features;
 	u64 driver_features_legacy;
+	struct device *parent = dev->dev.parent;
+	u64 dma_mask = min_not_zero(*parent->dma_mask,
+				    parent->bus_dma_limit);
+
+	if (dma_mask == DMA_BIT_MASK(64))
+		swiotlb_use_high(parent);
 
 	/* We have a driver! */
 	virtio_add_status(dev, VIRTIO_CONFIG_S_DRIVER);
-- 
2.17.1