drm/vmwgfx: Optimize memory footprint for DMA buffers.

Use VRAM whenever there is free space for DMA buffers,
but use system GMR memory if using VRAM would cause an eviction.

This significantly reduces the guest system memory usage for
VMs with a large amount of VRAM allocated.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_buffer.c b/drivers/gpu/drm/vmwgfx/vmwgfx_buffer.c
index 37a81925b15..825ebe3d89d 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_buffer.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_buffer.c
@@ -48,6 +48,15 @@ struct ttm_placement vmw_vram_placement = {
         .busy_placement = &vram_placement_flags
 };
 
+struct ttm_placement vmw_vram_sys_placement = {
+        .fpfn = 0,
+        .lpfn = 0,
+        .num_placement = 1,
+        .placement = &vram_placement_flags,
+        .num_busy_placement = 1,
+        .busy_placement = &sys_placement_flags
+};
+
 struct ttm_placement vmw_vram_ne_placement = {
         .fpfn = 0,
         .lpfn = 0,