Hi, Christian.
We have a use-case with i915 where the data representation of a buffer
object is larger in system memory than in LMEM/VRAM. Hence we'd like to
create a ttm_tt that is larger than the buffer object itself. Quickly
auditing the TTM code it looks like that should be pretty safe, as
ttm->num_pages is not really much accessed outside the tt code and the
pool code where we're doing the right thing.
The additional data will really only be accessed by the blitter so when
cpu-mapping, mapping just the original buffer object size is correct.
However with swapping the additional data needs to be swapped out and
the code is doing that correctly as well.
Do you think this is an acceptable solution?
/Thomas
