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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?TbkX9pvkApsyo9HwLptFrz4YtzLZmzSzoW6IrEL9bqVTWrL+DG+xP5DzzTQ8?= =?us-ascii?Q?RPO7WzA68W5pCvVaCMy3BBwqnR521KtDcpL2MQmkf0Uv1x2i2G8vxYpTTI7O?= =?us-ascii?Q?e9upLwxa51UojyGCrjNCXi0u6gyiKtmJfeExbh8deq0rUQb8jXHY0dlzz5CQ?= =?us-ascii?Q?gWt8m/PUmAgnoRKZEWpaPRHmuqNT4G6+IUDHX6Hpk2wVryn3lzBziYVHCx2b?= =?us-ascii?Q?1ytOd+yd6eWaK3eTlwF1C8pSis50Zy1vVsgy3ro24l6drHj+pbsbQraTYnrC?= =?us-ascii?Q?rhSIVHvuYWMHJ1GEpF0DTUWB6cUhO/GWcWgTCjWIlRWMxiKOFGYRZzeOkJck?= =?us-ascii?Q?bM7JCIqqThLjtLzsUDmjgM6HWozbdr3jZQ0IkvhHyEvj3QgOX7kEfFLsUiHg?= =?us-ascii?Q?K185sftoyQvK6lnwEyacCpD5ORMAg4SHxhvmcopns5pYrTtCxI8Uh+nw9aph?= =?us-ascii?Q?w276j8sP0hr6p6QB4LGRUI0NF5pTKYqOqFwMkT3QigZOs1wEG8ebdCYqcjqF?= =?us-ascii?Q?yhBHwDJCV8FdiczCecpP8MUIO2FpYvPXwtkIU/xfrSBv4yhcBcGUbB10gUXZ?= =?us-ascii?Q?7a4BVxSscyAQP3adtqKALIL5jiYNk5a+Ta67y/km6YEYX76GYvYUBV58zwMK?= =?us-ascii?Q?jC9oRkmhHIofLQ/9TI1BcwmyEkogvD/LCQrjHDNBmj3rOXMKU7APqDIHTv4y?= =?us-ascii?Q?TPJu+4zv5Ikl7Tzp0rdfhOCUM/WONoLvo6uIxd7snrMxPDtZB47Uyn+hcnx2?= =?us-ascii?Q?HNA5+oYRSzlj68me+uDoyXuxeyFhZ5Mvu4LvtPV5M0UMfn2KUTcE5zHEQ/Op?= =?us-ascii?Q?HoDQ4BvB1HfI0udfCC59pIs2ScC0A1+c/t2LBgxI/QcSp6pnUTAGzUKTED0V?= =?us-ascii?Q?QPqXHorg6HfRs02CBEZQ5t5eaStW2LfBrQa53cY+mTUAEG8Vy1p8e3wcm/KR?= =?us-ascii?Q?TF5RpcFbg8lHLeNzh3wEBRnH7H1RzgB0OBwyGQQdEvz6GKE0bwqlRCRKw4J6?= =?us-ascii?Q?fJgIKUa2nNZUy3bwcIDghXuFJ3scjmTQcMYVYkXSKJ7pknoDSxu78RPsNwB1?= =?us-ascii?Q?WIVI8Ep3dYSD+8i62UwJ/uPhnSEwJrL99JGqxGT2g6+McaOUJpw4XfJM8TLm?= =?us-ascii?Q?XKxF/Vfgh+YV3lGOcobD7bp0lY1Z/izglQOKbvFW+FMB5gFAc0OZh8VOLwgy?= =?us-ascii?Q?1Lzjo0B642yRkH/hawv7WBW3byAqOC6MqTQuL4v1fIm0ymqOms3XmoBv6FiZ?= =?us-ascii?Q?I8t4DVJEz6hTdhGD4iuQVT4JLLtYns4IQg1boih+WECxCR24bmwnQYwBI8Mf?= =?us-ascii?Q?KbjnvZ5dNSiYwoXP+5g/vfv5O145XuWhvZHxbA8dwt82RjZOLwEhdFkqWYCN?= =?us-ascii?Q?FRkYiGt3Ia2fTGtf8eA7uBTSqzjWrFrxsu/CtP7vgciEDJnmf0FbcaRvObGj?= =?us-ascii?Q?XVKXN7LiV+ViZGA+iLBXWNr5m+kGeO6AK0kvLe2AHZIjpqgLE6zbPZNZCL5W?= =?us-ascii?Q?NmCheAS3IW2oCF/ss8zF26tTc5D3qLuDPAAWqzXyolwtgqplxA2riT8H7mga?= =?us-ascii?Q?/0rf14rJXOzIRxM/u0iUAcY1q/wCxVXH0d8vkG/g?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 81e3619b-4a1c-49b3-155c-08db98f40252 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Aug 2023 16:16:38.3999 (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: 7iDwYuIvXKYnPm0dwB9NfolH6ZLGgq3E30bJ3Ac8YUYfyA/exZn6P3Ik9/vuqmHp X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW3PR12MB4522 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, Aug 09, 2023 at 06:16:19PM +0800, Baolu Lu wrote: > On 2023/8/8 23:35, Yi Liu wrote: > > +static int iommufd_fill_hw_info(struct device *dev, void __user *user_ptr, > > + unsigned int *length, u32 *type) > > +{ > > + const struct iommu_ops *ops; > > + unsigned int data_len; > > + void *data; > > + int rc = 0; > > + > > + ops = dev_iommu_ops(dev); > > + if (!ops->hw_info) { > > + *length = 0; > > + *type = IOMMU_HW_INFO_TYPE_NONE; > > + return 0; > > + } > > + > > + data = ops->hw_info(dev, &data_len, type); > > + if (IS_ERR(data)) > > + return PTR_ERR(data); > > + > > + /* > > + * drivers that have hw_info callback should have a unique > > + * iommu_hw_info_type. > > + */ > > + if (WARN_ON_ONCE(*type == IOMMU_HW_INFO_TYPE_NONE)) { > > + rc = -ENODEV; > > + goto err_free; > > + } > > + > > + *length = min(*length, data_len); > > + if (copy_to_user(user_ptr, data, *length)) { > > copy_to_user() returns the number of bytes that were successfully > copied, right? It returns length on failure and 0 on success Jason