Merge tag 'drm-next-2019-12-06' of git://anongit.freedesktop.org/drm/drm

Pull more drm updates from Dave Airlie:
 "Rob pointed out I missed his pull request for msm-next, it's been in
  next for a while outside of my tree so shouldn't cause any unexpected
  issues, it has some OCMEM support in drivers/soc that is acked by
  other maintainers as it's outside my tree.

  Otherwise it's a usual fixes pull, i915, amdgpu, the main ones, with
  some tegra, omap, mgag200 and one core fix.

  Summary:

  msm-next:
   - OCMEM support for a3xx and a4xx GPUs.
   - a510 support + display support

  core:
   - mst payload deletion fix

  i915:
   - uapi alignment fix
   - fix for power usage regression due to security fixes
   - change default preemption timeout to 640ms from 100ms
   - EHL voltage level display fixes
   - TGL DGL PHY fix
   - gvt - MI_ATOMIC cmd parser fix, CFL non-priv warning
   - CI spotted deadlock fix
   - EHL port D programming fix

  amdgpu:
   - VRAM lost fixes on BACO for CI/VI
   - navi14 DC fixes
   - misc SR-IOV, gfx10 fixes
   - XGMI fixes for arcturus
   - SRIOV fixes

  amdkfd:
   - KFD on ppc64le enabled
   - page table optimisations

  radeon:
   - fix for r1xx/2xx register checker.

  tegra:
   - displayport regression fixes
   - DMA API regression fixes

  mgag200:
   - fix devices that can't scanout except at 0 addr

  omap:
   - fix dma_addr refcounting"

* tag 'drm-next-2019-12-06' of git://anongit.freedesktop.org/drm/drm: (100 commits)
  drm/dp_mst: Correct the bug in drm_dp_update_payload_part1()
  drm/omap: fix dma_addr refcounting
  drm/tegra: Run hub cleanup on ->remove()
  drm/tegra: sor: Make the +5V HDMI supply optional
  drm/tegra: Silence expected errors on IOMMU attach
  drm/tegra: vic: Export module device table
  drm/tegra: sor: Implement system suspend/resume
  drm/tegra: Use proper IOVA address for cursor image
  drm/tegra: gem: Remove premature import restrictions
  drm/tegra: gem: Properly pin imported buffers
  drm/tegra: hub: Remove bogus connection mutex check
  ia64: agp: Replace empty define with do while
  agp: Add bridge parameter documentation
  agp: remove unused variable num_segments
  agp: move AGPGART_MINOR to include/linux/miscdevice.h
  agp: remove unused variable size in agp_generic_create_gatt_table
  drm/dp_mst: Fix build on systems with STACKTRACE_SUPPORT=n
  drm/radeon: fix r1xx/r2xx register checker for POT textures
  drm/amdgpu: fix GFX10 missing CSIB set(v3)
  drm/amdgpu: should stop GFX ring in hw_fini
  ...

1 files changed, 43 insertions, 7 deletions

diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c
index 746dae32c484..bc15b430156d 100644
--- a/drivers/gpu/drm/tegra/gem.c
+++ b/drivers/gpu/drm/tegra/gem.c
@@ -27,6 +27,29 @@ static void tegra_bo_put(struct host1x_bo *bo)
 	drm_gem_object_put_unlocked(&obj->gem);
 }
 
+/* XXX move this into lib/scatterlist.c? */
+static int sg_alloc_table_from_sg(struct sg_table *sgt, struct scatterlist *sg,
+				  unsigned int nents, gfp_t gfp_mask)
+{
+	struct scatterlist *dst;
+	unsigned int i;
+	int err;
+
+	err = sg_alloc_table(sgt, nents, gfp_mask);
+	if (err < 0)
+		return err;
+
+	dst = sgt->sgl;
+
+	for (i = 0; i < nents; i++) {
+		sg_set_page(dst, sg_page(sg), sg->length, 0);
+		dst = sg_next(dst);
+		sg = sg_next(sg);
+	}
+
+	return 0;
+}
+
 static struct sg_table *tegra_bo_pin(struct device *dev, struct host1x_bo *bo,
 				     dma_addr_t *phys)
 {
@@ -52,11 +75,31 @@ static struct sg_table *tegra_bo_pin(struct device *dev, struct host1x_bo *bo,
 		return ERR_PTR(-ENOMEM);
 
 	if (obj->pages) {
+		/*
+		 * If the buffer object was allocated from the explicit IOMMU
+		 * API code paths, construct an SG table from the pages.
+		 */
 		err = sg_alloc_table_from_pages(sgt, obj->pages, obj->num_pages,
 						0, obj->gem.size, GFP_KERNEL);
 		if (err < 0)
 			goto free;
+	} else if (obj->sgt) {
+		/*
+		 * If the buffer object already has an SG table but no pages
+		 * were allocated for it, it means the buffer was imported and
+		 * the SG table needs to be copied to avoid overwriting any
+		 * other potential users of the original SG table.
+		 */
+		err = sg_alloc_table_from_sg(sgt, obj->sgt->sgl, obj->sgt->nents,
+					     GFP_KERNEL);
+		if (err < 0)
+			goto free;
 	} else {
+		/*
+		 * If the buffer object had no pages allocated and if it was
+		 * not imported, it had to be allocated with the DMA API, so
+		 * the DMA API helper can be used.
+		 */
 		err = dma_get_sgtable(dev, sgt, obj->vaddr, obj->iova,
 				      obj->gem.size);
 		if (err < 0)
@@ -397,13 +440,6 @@ static struct tegra_bo *tegra_bo_import(struct drm_device *drm,
 		err = tegra_bo_iommu_map(tegra, bo);
 		if (err < 0)
 			goto detach;
-	} else {
-		if (bo->sgt->nents > 1) {
-			err = -EINVAL;
-			goto detach;
-		}
-
-		bo->iova = sg_dma_address(bo->sgt->sgl);
 	}
 
 	bo->gem.import_attach = attach;