gpu: nvgpu: fix debugfs to disable big pages

After setting 'Y' in disable_bigpage, in native SMMU case,
we could still see 64K GMMU pages beeing used.

Fixed the following:
    - enforce disable_bigpage in nvgpu_vm_map
    - update GPU characteristics so that new clients know
      whether or not big pages are enabled. For instance
      this may affect how CUDA requests memory mapping.

JIRA EVLR-1694

Change-Id: I62841096add3bd798c5c11090054f82c8a2be832
Signed-off-by: Thomas Fleury <tfleury@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1532429
Reviewed-by: Richard Zhao <rizhao@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: svccoveritychecker <svccoveritychecker@nvidia.com>
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/common/linux/vm.c b/drivers/gpu/nvgpu/common/linux/vm.c
index d47d6bb1..dec05209 100644
--- a/drivers/gpu/nvgpu/common/linux/vm.c
+++ b/drivers/gpu/nvgpu/common/linux/vm.c
@@ -260,7 +260,10 @@ u64 nvgpu_vm_map(struct vm_gk20a *vm,
                 map_offset = offset_align;
 
         bfr.align = nvgpu_get_buffer_alignment(g, sgl, aperture);
-        bfr.pgsz_idx = __get_pte_size(vm, map_offset,
+        if (g->mm.disable_bigpage)
+                bfr.pgsz_idx = gmmu_page_size_small;
+        else
+                bfr.pgsz_idx = __get_pte_size(vm, map_offset,
                                       min_t(u64, bfr.size, bfr.align));
         mapping_size = mapping_size ? mapping_size : bfr.size;