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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?n/pj+9yV2sTU95zc2jci9uWGb054jVtmRWTFhh2kgIVc+Mu6UIndBPYYfmJ2?= =?us-ascii?Q?OJbnMP3YU38cLNgNNm5X2VHKVChcJj6ZWni+LUdFdmDTF+scx/hG4tpKCTNe?= =?us-ascii?Q?RY+5KZMgA6y7DMrf/dMWONfuc437ItqCMUaTCg/e0+okc01Ab+OiCx8Ws7Jw?= =?us-ascii?Q?lZeKeIOuXzD+i6WkAxx3Jkc4imUvaU1U7gZJ4uMQxEzNj86+EbuWIlgpNhxw?= =?us-ascii?Q?UyjxDE1Oz4UC3tV8DsxyIVvzel7HQWDyz6rw5vWlR86HDfP1kJzvYC5RCOCQ?= =?us-ascii?Q?obc/YSp4tu7qv1tCs/zt+7VcfG+niQ5vH22e3f+xgNiT+Xib1rQuBfX/eDXq?= =?us-ascii?Q?SOGHSHmtcVoAQ7sIuxXV+Lxnl5QjGANGd/SNJO3UmJy6TlLMermS9WM7j5AQ?= =?us-ascii?Q?B12hDMv8pHGuyMFyhEo7S1ADnUG630dgqL2qh4N8h1KWgud/+23B/gfxGVa/?= =?us-ascii?Q?ZUBCIj4+xJVaVEJj4pewkQgJoMiymmNMrTWRFE6zuePqw4yKZcXtyPnEZVvu?= =?us-ascii?Q?NugxxIKlqwArUUQxTGZ7hCBVjFyHGFOxETqR/lFsc72CU/4LnvZkQcHdNKwL?= =?us-ascii?Q?yj9/4tDfQ1pj79rt/eCShNIsasGp9qRYHEy9BH+45PynUSIQ66eez03929di?= =?us-ascii?Q?vxA2QuUDpmb0A5s08iFmK8GCW362RpTmk0AOH+Eo2I8APHmTDtZ1lHSXWtKi?= =?us-ascii?Q?ymbXDQd79DiJbAjEIA99ZaCu88lbNDyHThE8FlqbGhX2CvpQaghwkNWKAEiQ?= =?us-ascii?Q?tvsdjIsNzfa/EG1hsUpNrE8OEuR1xziAmgxlu0dBjys7LeVDXbkW6bUYXoAH?= =?us-ascii?Q?dnAtpggl36RmPlvOnepnOJXmLmelL1LYsGubxzjOBLAinpvZW+rexbB2VL+m?= =?us-ascii?Q?k7/qYyz64euEnpi54zkIeQIrTuAbngDrWAf294bkIUj1yjz3utFnBqZsResI?= =?us-ascii?Q?YzeiFFJ8uM/LwmnJJqVwbomtHRS7pwT0FtIrSTpej9JeshVdEZYom7/x5ibJ?= =?us-ascii?Q?cE7M1zp72nFTjMG3tGgBrQYaSu6rTL40oIJ1RbFoI7+D6xo2wnNlBALzcWAA?= =?us-ascii?Q?DN3B3WhPLl/YbXhztb9m7GVnS8Ybm90rnhXxMHWYdlj99wXZnSICzUkee34t?= =?us-ascii?Q?XSSoeuoHaM2lom3+WOFAwamQgHwuy7gk3eGywnS9bDsCgTnAHPY6ctFbTrnm?= =?us-ascii?Q?Pfoyl6tWuXSsffSL/SiIINueKIB/I2KBTY8bEB335cHlIU0Km8tCEsW96cP9?= =?us-ascii?Q?kDSJu3qvVUd1JbeaUYCUIShzinAuAET9Su6JFVpNc2y0vIXlFHE70VV3sosY?= =?us-ascii?Q?9cvyaS0VQ1NYHYjgq2EtFkbz9wFnK51wVq+/LWUhzr08cCVtVxExDZbmjBqI?= =?us-ascii?Q?ZkHzwIhOYBl12KXMqtI7x+st9fQKAtyEYIWwi+aHhRijvvczjQdNUwLd8uqv?= =?us-ascii?Q?s/TOf0n/3J1yVxgMrc2dQ+98yDRJ6nPK/n5Tf1akEp/4s98qELskjFjxl1TD?= =?us-ascii?Q?qK8i0rkU3+IZtOQswSFxp8JxFdg4ovmiLa0XxLo1IZIKZgiAfyn39hYrcfMz?= =?us-ascii?Q?l3IzrVltGCXJtAG+dLTF3hD0tNCt4Zk69m9PlsG9q+aUl2BCWEOgc+YODRCC?= =?us-ascii?Q?PVjw1lm488Szk6xSUCeFQzAVZQfGAkveC88LoWdelTqI/bilNIuNiZ44SnKa?= =?us-ascii?Q?bOl+iLZ/7t0Wqlp/E77WQb8adVotyEjZKPTwTYu024d8zfMi?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: fdb8a7bb-3741-4279-f445-08dee2ac1537 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Jul 2026 20:03:05.3309 (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: Y8HMBYURVMb99lcd8XxdA0wpFDQXb+/vMnojE1PhcOiMS7ipZ6BEu30DvpQtnwq+ X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW9PR12MB999208 On Tue, Jul 14, 2026 at 11:48:49AM -0700, Nicolin Chen wrote: > The cache invalidation ops, cache_invalidate_user() for a nested HWPT and > the cache_invalidate() for a vIOMMU, are each handed the full user request > array and report how many of the array entries they handled by setting the > array->entry_num. Every driver therefore implements its own loop over the > array, and a driver wanting to process that array in fixed-size chunks > (e.g. to issue commands out of a fixed-size on-stack buffer) has to carry > the loop and its sub-array bookkeeping all on its own. > > Move the iteration into the iommufd core instead. Invoke the op with a > sub-array that starts at the first not-yet-handled entry, let it handle a > prefix of that sub-array and report the count via array->entry_num, then > advance the base pointer and re-invoke the op until the entire array has > been consumed or until the op returns an error along the way. > > A driver that handles the entire window in one single call, as all of the > current drivers happen to do, finishes the loop in just one pass, so this > does not change any of the existing behavior. It instead lets each of the > drivers convert to bounded chunk processing on its own, done by each of the > subsequent changes. > > Suggested-by: Jason Gunthorpe > Reviewed-by: Kevin Tian > Reviewed-by: Lu Baolu > Reviewed-by: Pranjal Shrivastava > Assisted-by: Claude:claude-opus-4-8 > Signed-off-by: Nicolin Chen > --- > include/linux/iommu.h | 6 ++++-- > include/linux/iommufd.h | 2 ++ > drivers/iommu/iommufd/hw_pagetable.c | 25 +++++++++++++++---------- > 3 files changed, 21 insertions(+), 12 deletions(-) Reviewed-by: Jason Gunthorpe Jason