[PATCH 01/12] drm/amdgpu: implement vm_operations_struct.access

[Michel Dänzer]

On 12/07/17 02:37 PM, Felix Kuehling wrote:
> Any comments on this one?
> 
> This was requested by the HSA runtime team a long time ago as a
> debugging feature. It allows gdb to access the content of CPU-mapped
> BOs. I imagine this may be useful for user mode driver developers.

Adding the dri-devel list.


>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> index 15148f1..3f927c2 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> @@ -1237,6 +1237,134 @@ void amdgpu_ttm_set_active_vram_size(struct amdgpu_device *adev, u64 size)
>>  	man->size = size >> PAGE_SHIFT;
>>  }
>>  
>> +static struct vm_operations_struct amdgpu_ttm_vm_ops;
>> +static const struct vm_operations_struct *ttm_vm_ops /* = NULL;
>> +						      * (appease checkpatch) */;

How does this appease checkpatch?


>> +static int amdgpu_ttm_bo_access_kmap(struct amdgpu_bo *abo,
>> +				     unsigned long offset,
>> +				     void *buf, int len, int write)
>> +{
>> +	struct ttm_buffer_object *bo = &abo->tbo;
>> +	struct ttm_bo_kmap_obj map;
>> +	void *ptr;
>> +	bool is_iomem;
>> +	int r;
>> +
>> +	r = ttm_bo_kmap(bo, 0, bo->num_pages, &map);
>> +	if (r)
>> +		return r;
>> +	ptr = (uint8_t *)ttm_kmap_obj_virtual(&map, &is_iomem) + offset;
>> +	WARN_ON(is_iomem);
>> +	if (write)
>> +		memcpy(ptr, buf, len);
>> +	else
>> +		memcpy(buf, ptr, len);
>> +	ttm_bo_kunmap(&map);
>> +
>> +	return len;
>> +}

This could be in TTM, right? As a helper function and/or a generic
vm_operations_struct::access hook (at least for GTT/CPU domains).


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer