ttm_resource_manager::use_tt

[Thomas Hellström (Intel)]

On 5/28/21 9:30 PM, Zack Rusin wrote:
> On 5/22/21 3:13 AM, Christian König wrote:
>> Hi Zack,
>>
>> IIRC that was for the VMW_PL_GMR type, wasn't it?
>>
>> As far as I have seen that backend was just giving out unique numbers 
>> and it looked questionable that we allocated pages for that.
>>
>> E.g. when you set that flag then for each allocation we also allocate 
>> a TTM tt structure and a corresponding page.
>>
>
> Got ya. Yea, it's a little messy. I think it's correct. Those unique 
> numbers are just identifiers for the bo's but the actual memory for 
> them is regular system memory (e.g. we just tell our virtual hardware, 
> here's some guest system pages and here's a unique id that we'll be 
> using the refer to them).
>
>
Yes, allocating pages for that memory type is correct. The main 
difference to other hardware here is that on other hardware those are 
bound to gpu using a range in a translation table. With vmwgfx they are 
bound using a slot with a unique integer..

/Thomas