drm/amdgpu/dma_buf: fix page_link check

[ Upstream commit c0dd8a9253fadfb8e5357217d085f1989da4ef0a ]

The page_link lower bits of the first sg could contain something like
SG_END, if we are mapping a single VRAM page or contiguous blob which
fits into one sg entry. Rather pull out the struct page, and use that in
our check to know if we mapped struct pages vs VRAM.

Fixes: f44ffd677fb3 ("drm/amdgpu: add support for exporting VRAM using DMA-buf v3")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: amd-gfx@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.8+
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
index bbbacc7b6c463483c10572802e941dcf27659d99..e4d0a9377e712e0ced898bdfea241e415df69c39 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
@@ -357,7 +357,7 @@ static void amdgpu_dma_buf_unmap(struct dma_buf_attachment *attach,
                                 struct sg_table *sgt,
                                 enum dma_data_direction dir)
 {
-       if (sgt->sgl->page_link) {
+       if (sg_page(sgt->sgl)) {
                dma_unmap_sgtable(attach->dev, sgt, dir, 0);
                sg_free_table(sgt);
                kfree(sgt);