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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?sCeqPh2BjSGEuEWGw2zngwakMA2iJPCusLg5whCTlSw9/iuDckISthJgo1Ie?= =?us-ascii?Q?gEOiqLgRzjWMA9KkPmZzLRVzdeb+2n2N224rIu+ehSIdY6RJjxHQ03wYYW33?= =?us-ascii?Q?3EBXAreg5XJXqO4fUV2fYcFC2Rz5MuyAyLY+AiepLLH+Iwi7lWzcw6iXrpbg?= =?us-ascii?Q?3w6V61dy/9IYe5lt7M/y3UXCi/5VfY8LX52gGTjmK89v7Ti4ajEX97XtHYja?= =?us-ascii?Q?1+IWDN9OteBk0dj26C2p0BjjPA4yKRm1JXqauJvyXPX+gjRabr2oGv/gtLnJ?= =?us-ascii?Q?/0n814K0rHe4DT4w8hjyRZCOsg4xyGyyVGF2BbFLY5dGhfNnib0lzLh5S6Zm?= =?us-ascii?Q?dF8wCnErla6tI/BrMXrPFVEoNVV3x+soz050BsUXbOju4XJqvWl39wI2KB+D?= =?us-ascii?Q?YAK1AvlBkYF2ugYKnKF49onNydAr86Ep0E86g9WAPmGq6hq+UPjFTA1eDxhx?= =?us-ascii?Q?dtDZAYS5MDHHpYmzlWvy8Hd0nAss3Hy886ZLeXKOsZRHUvjjWMHR3jC2Mfv+?= =?us-ascii?Q?qXUhzCT00iYyBSJzd42ZteTFW4mG0RfU7UVH6lYRF22CrsJtZSToMvCfy9Vf?= =?us-ascii?Q?BxR8cjFpoNw0gYvsgWLrmBUG8AQS8UWeNtbLJ1BJa1L4L6oeapzlw/SjQszT?= =?us-ascii?Q?FLPVMr7FpE+BKgZGHfYACQLg12/CBXWc/ceTyLIY62y2JFanvhyTnKW45kTz?= =?us-ascii?Q?6iKhsnicVgMbneyPVAOXDQaxLoDExBR77LU7lPiD1FMZ6pcpZxLt68uBEolf?= =?us-ascii?Q?K3zoUoGPnOu2dCa1G87SQQiWG5s0ttsmXVdrHeJUQBmslS1zGKLev3xcKjqC?= =?us-ascii?Q?2xtS+2m3RFtg0IgXt73ZopCfuXsm7FFOTgzj4Xj+bJK5Oa9to9RB+VaYy0UB?= =?us-ascii?Q?i3br1znH3t0xbnbdb94oFJ8SfAk0pTOOnWD5stGJhgJZMkKXpvH3Tjg9Z6jL?= =?us-ascii?Q?s4hE0OBAXQOLTAgqFh40nT2a4560pXTX0QH4P4t3nMLy8u0MTybrm8Pjm4k6?= =?us-ascii?Q?D0phWjMiOyXA4DMxfRh08kqu0yAE92x+aqtce0ZJ376g3RsRF2w0Pu+8WIXp?= =?us-ascii?Q?r3bzhu2SobNly0eX0OmBFzzqb+mdCPhz/AccYOiouxzgceQXtvlmd2DCqqAm?= =?us-ascii?Q?NK+My5fRmXEWIYuy67fG+Cbn7VfYMFaHeAWBFIZekMtUIrcpL9dTu7CJqJcG?= =?us-ascii?Q?UGsuMEFE01/7hyJ0tO1VdQDRMpNl0SEGjbx8mV6eTcX2zYugoYbTU7q23JpD?= =?us-ascii?Q?ccL/LUBz8CjQnBoAgqgRVL8Stok0xspu64/g5S5/LmfhXi0gC6Nh36LGFG3W?= =?us-ascii?Q?GSuiF/kh1E11Hb0LLX1xN8RxglOs367wTfwlEejx4rFsMOLQMuQy/QHkvus9?= =?us-ascii?Q?7nQFH1oWxAaWOqbyK+YdRkFoli43Uoaq3I7PD78mPtno3A1Cx/oYham8OGLQ?= =?us-ascii?Q?lhrjximJ7csYQ0YEK06mZs1RRMtMs7Zq1DqF6oDUuSdHyBYtZ35V0tRZrBfF?= =?us-ascii?Q?9vWxv+p5Qcpt5A6oZu7/DpMwmdFJ2p9hNEhtRhARjPYzNV0oNGeZtWvQbTil?= =?us-ascii?Q?qsfyKOKG5Od1sMpSoFA=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: ba360f68-ee97-410c-a45b-08dad20bc47b X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Nov 2022 13:15:21.0819 (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: cQkzSOMyE/xYE/s1Q6jmT+abnz4+QPTdGZk+yfMaHIKVxfwdB1KedXeORbt5s+P8 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB5184 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 29, 2022 at 10:02:46AM +0800, liulongfang wrote: > On 2022/11/28 21:39, Jason Gunthorpe wrote: > > On Mon, Nov 28, 2022 at 11:11:56AM +0800, Longfang Liu wrote: > > > >> @@ -119,6 +132,9 @@ struct vfio_migration_ops { > >> enum vfio_device_mig_state *curr_state); > >> int (*migration_get_data_size)(struct vfio_device *device, > >> unsigned long *stop_copy_length); > >> + int (*migration_get_data)(struct vfio_device *device, char *buffer); > >> + int (*migration_get_attr)(struct vfio_device *device, char *buffer); > >> + int (*migration_debug_operate)(struct vfio_device *device, > >> unsigned int cmd); > > > > Please don't do wrappers like this, give the variant driver a chance > > to create its own files natively under the debugfs directory > > > > Using this public debugfs file does not need to deal with file > creation and destruction. > The driver only needs to define its debug operation command, > isn't it simpler? No, it is obfuscating the normal kernel apis, what if a driver wants two files? debugfs is not a heavy burden to implement files for. Jason