drm/amdgpu/dma_buf: fix page_link check

commit c0dd8a9253fadfb8e5357217d085f1989da4ef0a upstream.

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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
index ba3a87cb88ccc9de8ea6ad71012d880ab1777336..be4cc4868a748e1942365368aca0827bb7b425f7 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
@@ -211,7 +211,7 @@ 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);