Am 2022-01-17 um 6:43 p.m. schrieb Jonathan Kim: > drm_dev_enter returns true when accessiable so correct the error check. > > Source VRAM buffer is reserved by TTM but not pinned so the gpu offset > fetch throws a warning. Get the gpu offset without a check and then > double check to make sure the source buffer hasn't fallen into a hole. > Otherwise use MMIO access to deal with non-contiguous VRAM cases as > usual.
There is a way to get the correct offset for non-contiguous memory the same way amdgpu_ttm_access_memory does, using amdgpu_res_first. Since you only need a single page, you should never need amdgpu_res_next. Just make sure that the cursor.size >= len. Regards, Felix > > Signed-off-by: Jonathan Kim <[email protected]> > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 19 +++++++++++++++---- > 1 file changed, 15 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c > b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c > index 6178ae7ba624..0acfd872bfef 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c > @@ -1440,6 +1440,7 @@ static int amdgpu_ttm_access_memory_sdma(struct > ttm_buffer_object *bo, > struct dma_fence *fence; > uint64_t src_addr, dst_addr; > unsigned int num_dw; > + bool vram_is_contiguous; > int r, idx; > > if (len != PAGE_SIZE) > @@ -1448,9 +1449,8 @@ static int amdgpu_ttm_access_memory_sdma(struct > ttm_buffer_object *bo, > if (!adev->mman.sdma_access_ptr) > return -EACCES; > > - r = drm_dev_enter(adev_to_drm(adev), &idx); > - if (r) > - return r; > + if (!drm_dev_enter(adev_to_drm(adev), &idx)) > + return -ENODEV; > > if (write) > memcpy(adev->mman.sdma_access_ptr, buf, len); > @@ -1460,7 +1460,18 @@ static int amdgpu_ttm_access_memory_sdma(struct > ttm_buffer_object *bo, > if (r) > goto out; > > - src_addr = amdgpu_bo_gpu_offset(abo); > + src_addr = amdgpu_bo_gpu_offset_no_check(abo); > + vram_is_contiguous = (adev->gmc.real_vram_size - 1 == > + adev->gmc.vram_end - adev->gmc.vram_start) && > + src_addr >= adev->gmc.vram_start && > + src_addr + len <= adev->gmc.vram_end; > + > + if (!vram_is_contiguous) { > + amdgpu_job_free(job); > + r = -EACCES; > + goto out; > + } > + > dst_addr = amdgpu_bo_gpu_offset(adev->mman.sdma_access_bo); > if (write) > swap(src_addr, dst_addr);
