On Wed, Mar 11, 2020 at 02:51:56PM +0100, Christian König wrote: > Check if we can do peer2peer on the PCIe bus. > > Signed-off-by: Christian König <christian.koenig@xxxxxxx> > drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c > index aef12ee2f1e3..bbf67800c8a6 100644 > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c > @@ -38,6 +38,7 @@ > #include <drm/amdgpu_drm.h> > #include <linux/dma-buf.h> > #include <linux/dma-fence-array.h> > +#include <linux/pci-p2pdma.h> > > /** > * amdgpu_gem_prime_vmap - &dma_buf_ops.vmap implementation > @@ -179,6 +180,9 @@ static int amdgpu_dma_buf_attach(struct dma_buf *dmabuf, > struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev); > int r; > > + if (pci_p2pdma_distance_many(adev->pdev, &attach->dev, 1, true) < 0) > + attach->peer2peer = false; > + Are there other related patches than this series? p2p dma mapping needs to be done in common code, in p2pdma.c - ie this open coding is missing the bus_offset stuff, at least. I really do not want to see drivers open code this stuff. We already have a p2pdma API for handling the struct page case, so I suggest adding some new p2pdma API to handle this for non-struct page cases. ie some thing like: int 'p2pdma map bar'( struct pci_device *source, unsigned int source_bar_number, struct pci_device *dest, physaddr&len *array_of_offsets & length pairs into source bar, struct scatterlist *output_sgl) Jason
