Re: [PATCH v5 3/3] drm/amdgpu: Drop vm_manager PASID to VM mapping

On 7/8/26 17:27, Srinivasan Shanmugam wrote:
> VM lookup users now resolve DRM PASIDs through the global PASID xarray:
> 
> 	PASID -> fpriv -> VM
> 
> The per-device vm_manager.pasids xarray is no longer needed.
> 
> Remove PASID registration and removal from the VM init/fini paths, drop
> vm_manager PASID initialization/cleanup, and remove the xarray from
> struct amdgpu_vm_manager.
> 
> Cc: Alex Deucher <[email protected]>
> Cc: Christian König <[email protected]>
> Signed-off-by: Srinivasan Shanmugam <[email protected]>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 25 ++-----------------------
>  drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h |  4 ----
>  2 files changed, 2 insertions(+), 27 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> index 11822bf832f8..579dbceecdc4 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> @@ -2642,14 +2642,7 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm,
>  	if (r)
>  		dev_dbg(adev->dev, "Failed to create task info for VM\n");
>  
> -	/* Store new PASID in XArray (if non-zero) */
> -	if (pasid != 0) {
> -		r = xa_err(xa_store_irq(&adev->vm_manager.pasids, pasid, vm, GFP_KERNEL));
> -		if (r < 0)
> -			goto error_free_root;
> -
> -		vm->pasid = pasid;
> -	}
> +	vm->pasid = pasid;

Yeah please remove the pasid parameter from amdgpu_vm_init() and nuke all the related code.

Apart from that the patch look good to me.

Regards,
Christian.

>  
>  	amdgpu_bo_unreserve(vm->root.bo);
>  	amdgpu_bo_unref(&root_bo);
> @@ -2657,11 +2650,7 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm,
>  	return 0;
>  
>  error_free_root:
> -	/* If PASID was partially set, erase it from XArray before failing */
> -	if (vm->pasid != 0) {
> -		xa_erase_irq(&adev->vm_manager.pasids, vm->pasid);
> -		vm->pasid = 0;
> -	}
> +	vm->pasid = 0;
>  	amdgpu_vm_pt_free_root(adev, vm);
>  	amdgpu_bo_unreserve(vm->root.bo);
>  	amdgpu_bo_unref(&root_bo);
> @@ -2768,11 +2757,6 @@ void amdgpu_vm_fini(struct amdgpu_device *adev, struct amdgpu_vm *vm)
>  
>  	root = amdgpu_bo_ref(vm->root.bo);
>  	amdgpu_bo_reserve(root, true);
> -	/* Remove PASID mapping before destroying VM */
> -	if (vm->pasid != 0) {
> -		xa_erase_irq(&adev->vm_manager.pasids, vm->pasid);
> -		vm->pasid = 0;
> -	}
>  	dma_fence_wait(vm->last_unlocked, false);
>  	dma_fence_put(vm->last_unlocked);
>  	dma_fence_wait(vm->last_tlb_flush, false);
> @@ -2868,8 +2852,6 @@ void amdgpu_vm_manager_init(struct amdgpu_device *adev)
>  #else
>  	adev->vm_manager.vm_update_mode = 0;
>  #endif
> -
> -	xa_init_flags(&adev->vm_manager.pasids, XA_FLAGS_LOCK_IRQ);
>  }
>  
>  /**
> @@ -2881,9 +2863,6 @@ void amdgpu_vm_manager_init(struct amdgpu_device *adev)
>   */
>  void amdgpu_vm_manager_fini(struct amdgpu_device *adev)
>  {
> -	WARN_ON(!xa_empty(&adev->vm_manager.pasids));
> -	xa_destroy(&adev->vm_manager.pasids);
> -
>  	amdgpu_vmid_mgr_fini(adev);
>  	amdgpu_pasid_mgr_cleanup();
>  }
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
> index 939f639cd8bf..f63364f128bf 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
> @@ -481,10 +481,6 @@ struct amdgpu_vm_manager {
>  	 */
>  	int					vm_update_mode;
>  
> -	/* PASID to VM mapping, will be used in interrupt context to
> -	 * look up VM of a page fault
> -	 */
> -	struct xarray				pasids;
>  	/* Global registration of recent page fault information */
>  	struct amdgpu_vm_fault_info	fault_info;
>  };