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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?KGve0Ce8hSfwG0NiqE3FGjH5jfb+24ov0TsZQxmTbpZ02aY+mAKdABN8BNRl?= =?us-ascii?Q?ZTY4gaIaeAaAmg40OJH4llIfDOdYxDh9gmzzJeTT0PooM+HGcjbAh0WjYVNP?= =?us-ascii?Q?Z8NkIj8piblPCfJlgYlBufm6UBh5SN/ueo+9/GFpec65TRln5wPxuIaP6EOM?= =?us-ascii?Q?e71GW86o0mK24QCTnv8mFd8xyWilKcqr6epND30nBpCmYomF8QshmRpII4iE?= =?us-ascii?Q?1DGGk9f5TNh2ZNceszwLxb75tby6FPpkofA8zbFzyZqZhcQzfLAmivE1ybWv?= =?us-ascii?Q?qoMb1QbxBIPbd2c1yr+i46DBI/Y8Euz6bUt7qfXLBoK4E32KQH2Xbky9WgTY?= =?us-ascii?Q?X03otjsmqVcQBf3h0kFM0k7+CxxYu6Lry3w/W9uuIbMyaPrPc7nF3EKVpVk/?= =?us-ascii?Q?4K+2S0HQ5zwMSaiYN0c5LpZW/843+ky2cGUWZ0AVyOlKhILPltMxGHB9X0bu?= =?us-ascii?Q?W1ZM2SkdnPNVh+hw2Ma+nr5f8RWrSa+A1uRJcESt9FPC74cHrE3yFLV8c/uS?= =?us-ascii?Q?VrdFnvBFEC3yqtoFJKj0oNK2Ku+jnOZ6HF+mNPb/aE7NPHx+WKHnDzWOso8O?= =?us-ascii?Q?IUxWxZhkPWz+c1N+IzZvukbTJUStl6OmQQxDTaZ1VF+vA3DZYHJnMrwMh0ii?= =?us-ascii?Q?jLrk7bY8NUakpZtUeh9EwoaU8NvDMvgFNUuJ1hSPNYHs8UARGHuPfvwaooSD?= =?us-ascii?Q?xWhZooJkX5L32GVC+68xjC15FlABDAwJu6ZymJZ2YeSu6s3kYwskvkh0Au/+?= =?us-ascii?Q?gVKrbTeHszNNJohPPMLqpczY7XuDD5KNR5DY9/DGWXLbfeJeVFHuTskzwz2d?= =?us-ascii?Q?hddw+LZ6W80Jvs1zigmNaQNfUZZ2crTNaDgi4zV/wV051W2Kgw3pjWzlrk40?= =?us-ascii?Q?sqWYXIdtA7ncbx5EDcWE1LfgVWCbpPlbcFq6O5KkLsYKMCsEOOoqMhNIZCrv?= =?us-ascii?Q?zPyx5rSiJmOF4wqiDxKoLr13Hug0ZJlOUwKHPBWm4KD8Zb4hZfYSNh/TNqM2?= =?us-ascii?Q?ulBqAhSCEnhwRa1eSb50hNcdr0W3X/slcO1BTW1HMDduZjZbWZ3WtM4tPhJv?= =?us-ascii?Q?gL+wTYfV7HrLRDt+ilUJnEgal7VSMyS/fdYi8gtaWmBW4/KuOT6bGt8ennpS?= =?us-ascii?Q?JCEVk4X5JFu7L9PQ/8sMO9iLHb6kSJ8LWdI1XBYdEILUv95w5ZLoUaq28gSA?= =?us-ascii?Q?EL7ybg3p4kp2mRwxVpz89SgW5aIRTnst+Kl0fDvjRMgCyZpHAajH8qhSacmN?= =?us-ascii?Q?Cirzj4CdEq2uZNRRcV3rLS1EnZTH0LASNTNYoda7oLDr5VyjmHw0dZKOqNC3?= =?us-ascii?Q?cMdd4J4TJlxlqlASG3hZZwAjSxGwiv8fm4geaQZ/gnPQ37YGLjJrE6OhrWtY?= =?us-ascii?Q?IocFIi8i3cYKqBKx0RPH21e3U08b2NnIdI6m3tR9osjF/VNRyJu4zM5SRQw3?= =?us-ascii?Q?5DNWt5in50LRziM06BJfmAu0P/qqF1RFMcHDPaP3uXMx+Mphgi35Dpg0P/KU?= =?us-ascii?Q?bdtA2yyGZK0lzH+HBUSVnKMq3Di1X68DMtXYVXffAzTafGDLNOY4aRnUPfMa?= =?us-ascii?Q?akvDB859oGJBX6ZrWkpHMGYKIfe41XRB49M1HzgQ?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c6b74851-dec6-4dd0-09f4-08db8eafc959 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Jul 2023 14:43:05.4362 (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: uKGQtzbhn39Ur9EVSGnYtWc9SJ2Tu0W0DSSagbXveHL6IVyGzReaQ1n+m624d1Mf X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB5783 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 27, 2023 at 07:57:57AM +0000, Tian, Kevin wrote: > > From: Liu, Yi L > > Sent: Monday, July 24, 2023 7:00 PM > > > > @@ -252,11 +258,20 @@ struct iommu_iotlb_gather { > > * @remove_dev_pasid: Remove any translation configurations of a specific > > * pasid, so that any DMA transactions with this pasid > > * will be blocked by the hardware. > > + * @hw_info_type: One of enum iommu_hw_info_type defined in > > + * include/uapi/linux/iommufd.h. It is used to tag the type > > + * of data returned by .hw_info callback. The drivers that > > + * support .hw_info callback should define a unique type > > + * in include/uapi/linux/iommufd.h. For the drivers that do > > + * not implement .hw_info callback, this field is > > + * IOMMU_HW_INFO_TYPE_NONE which is 0. Hence, such drivers > > + * do not need to care this field. > > every time looking at this field the same question came out why it is required > (and looks I forgot your previous response). > > e.g. why cannot the type be returned in @hw_info(): > > void *(*hw_info)(struct device *dev, u32 *length, int *type); u32 *type > NULL callback implies IOMMU_HW_INFO_TYPE_NONE. If every one of these queries has its own type it makes sense Though, is it not possible that we can have a type for the entire driver? Jason