RFC: use dma_alloc_noncoherent in ttm_pool_alloc_page

[Christoph Hellwig]

Hi all,

the memory allocation for the TTM pool is a big mess with two allocation
methods that both have issues, a layering violation and odd guessing of
pools in the callers.

This patch switches to the dma_alloc_noncoherent API instead fixing all
of the above issues.

Warning:  i don't have any of the relevant hardware, so this is a compile
tested request for comments only!

Diffstat:
 drivers/gpu/drm/amd/amdgpu/amdgpu.h     |    1 
 drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c |    4 
 drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c   |    1 
 drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c   |    1 
 drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c   |    1 
 drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c   |    1 
 drivers/gpu/drm/drm_cache.c             |   31 -----
 drivers/gpu/drm/drm_gem_vram_helper.c   |    3 
 drivers/gpu/drm/nouveau/nouveau_ttm.c   |    8 -
 drivers/gpu/drm/qxl/qxl_ttm.c           |    3 
 drivers/gpu/drm/radeon/radeon.h         |    1 
 drivers/gpu/drm/radeon/radeon_device.c  |    1 
 drivers/gpu/drm/radeon/radeon_ttm.c     |    4 
 drivers/gpu/drm/ttm/ttm_device.c        |    7 -
 drivers/gpu/drm/ttm/ttm_pool.c          |  178 ++++----------------------------
 drivers/gpu/drm/ttm/ttm_tt.c            |   25 ----
 drivers/gpu/drm/vmwgfx/vmwgfx_drv.c     |    4 
 include/drm/drm_cache.h                 |    1 
 include/drm/ttm/ttm_device.h            |    3 
 include/drm/ttm/ttm_pool.h              |    9 -
 20 files changed, 41 insertions(+), 246 deletions(-)