Merge tag 'drm-for-v4.16' of git://people.freedesktop.org/~airlied/linux

Pull drm updates from Dave Airlie:
 "This seems to have been a comparatively quieter merge window, I assume
  due to holidays etc. The "biggest" change is AMD header cleanups, which
  merge/remove a bunch of them. The AMD gpu scheduler is now being made generic
  with the etnaviv driver wanting to reuse the code, hopefully other drivers
  can go in the same direction.

  Otherwise it's the usual lots of stuff in i915/amdgpu, not so much stuff
  elsewhere.

  Core:
   - Add .last_close and .output_poll_changed helpers to reduce driver footprints
   - Fix plane clipping
   - Improved debug printing support
   - Add panel orientation property
   - Update edid derived properties at edid setting
   - Reduction in fbdev driver footprint
   - Move amdgpu scheduler into core for other drivers to use.

  i915:
   - Selftest and IGT improvements
   - Fast boot prep work on IPS, pipe config
   - HW workarounds for Cannonlake, Geminilake
   - Cannonlake clock and HDMI2.0 fixes
   - GPU cache invalidation and context switch improvements
   - Display planes cleanup
   - New PMU interface for perf queries
   - New firmware support for KBL/SKL
   - Geminilake HW workaround for perforamce
   - Coffeelake stolen memory improvements
   - GPU reset robustness work
   - Cannonlake horizontal plane flipping
   - GVT work

  amdgpu/radeon:
   - RV and Vega header file cleanups (lots of lines gone!)
   - TTM operation context support
   - 48-bit GPUVM support for Vega/RV
   - ECC support for Vega
   - Resizeable BAR support
   - Multi-display sync support
   - Enable swapout for reserved BOs during allocation
   - S3 fixes on Raven
   - GPU reset cleanup and fixes
   - 2+1 level GPU page table

  amdkfd:
   - GFX7/8 SDMA user queues support
   - Hardware scheduling for multiple processes
   - dGPU prep work

  rcar:
   - Added R8A7743/5 support
   - System suspend/resume support

  sun4i:
   - Multi-plane support for YUV formats
   - A83T and LVDS support

  msm:
   - Devfreq support for GPU

  tegra:
   - Prep work for adding Tegra186 support
   - Tegra186 HDMI support
   - HDMI2.0 and zpos support by using generic helpers

  tilcdc:
   - Misc fixes

  omapdrm:
   - Support memory bandwidth limits
   - DSI command mode panel cleanups
   - DMM error handling

  exynos:
   - drop the old IPP subdriver.

  etnaviv:
   - Occlusion query fixes
   - Job handling fixes
   - Prep work for hooking in gpu scheduler

  armada:
   - Move closer to atomic modesetting
   - Allow disabling primary plane if overlay is full screen

  imx:
   - Format modifier support
   - Add tile prefetch to PRE
   - Runtime PM support for PRG

  ast:
   - fix LUT loading"

* tag 'drm-for-v4.16' of git://people.freedesktop.org/~airlied/linux: (1471 commits)
  drm/ast: Load lut in crtc_commit
  drm: Check for lessee in DROP_MASTER ioctl
  drm: fix gpu scheduler link order
  drm/amd/display: Demote error print to debug print when ATOM impl missing
  dma-buf: fix reservation_object_wait_timeout_rcu once more v2
  drm/amdgpu: Avoid leaking PM domain on driver unbind (v2)
  drm/amd/amdgpu: Add Polaris version check
  drm/amdgpu: Reenable manual GPU reset from sysfs
  drm/amdgpu: disable MMHUB power gating on raven
  drm/ttm: Don't unreserve swapped BOs that were previously reserved
  drm/ttm: Don't add swapped BOs to swap-LRU list
  drm/amdgpu: only check for ECC on Vega10
  drm/amd/powerplay: Fix smu_table_entry.handle type
  drm/ttm: add VADDR_FLAG_UPDATED_COUNT to correctly update dma_page global count
  drm: Fix PANEL_ORIENTATION_QUIRKS breaking the Kconfig DRM menuconfig
  drm/radeon: fill in rb backend map on evergreen/ni.
  drm/amdgpu/gfx9: fix ngg enablement to clear gds reserved memory (v2)
  drm/ttm: only free pages rather than update global memory count together
  drm/amdgpu: fix CPU based VM updates
  drm/amdgpu: fix typo in amdgpu_vce_validate_bo
  ...

1 files changed, 48 insertions, 8 deletions

diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
index cb4d09c70fd4..0b7b0d1ad2d5 100644
--- a/drivers/gpu/drm/drm_syncobj.c
+++ b/drivers/gpu/drm/drm_syncobj.c
@@ -29,9 +29,9 @@
 /**
  * DOC: Overview
  *
- * DRM synchronisation objects (syncobj) are a persistent objects,
- * that contain an optional fence. The fence can be updated with a new
- * fence, or be NULL.
+ * DRM synchronisation objects (syncobj, see struct &drm_syncobj) are
+ * persistent objects that contain an optional fence. The fence can be updated
+ * with a new fence, or be NULL.
  *
  * syncobj's can be waited upon, where it will wait for the underlying
  * fence.
@@ -61,7 +61,8 @@
  * @file_private: drm file private pointer
  * @handle: sync object handle to lookup.
  *
- * Returns a reference to the syncobj pointed to by handle or NULL.
+ * Returns a reference to the syncobj pointed to by handle or NULL. The
+ * reference must be released by calling drm_syncobj_put().
  */
 struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private,
 				     u32 handle)
@@ -106,7 +107,8 @@ static int drm_syncobj_fence_get_or_add_callback(struct drm_syncobj *syncobj,
 	 * callback when a fence has already been set.
 	 */
 	if (syncobj->fence) {
-		*fence = dma_fence_get(syncobj->fence);
+		*fence = dma_fence_get(rcu_dereference_protected(syncobj->fence,
+								 lockdep_is_held(&syncobj->lock)));
 		ret = 1;
 	} else {
 		*fence = NULL;
@@ -168,8 +170,9 @@ void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
 
 	spin_lock(&syncobj->lock);
 
-	old_fence = syncobj->fence;
-	syncobj->fence = fence;
+	old_fence = rcu_dereference_protected(syncobj->fence,
+					      lockdep_is_held(&syncobj->lock));
+	rcu_assign_pointer(syncobj->fence, fence);
 
 	if (fence != old_fence) {
 		list_for_each_entry_safe(cur, tmp, &syncobj->cb_list, node) {
@@ -227,6 +230,19 @@ static int drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj)
 	return 0;
 }
 
+/**
+ * drm_syncobj_find_fence - lookup and reference the fence in a sync object
+ * @file_private: drm file private pointer
+ * @handle: sync object handle to lookup.
+ * @fence: out parameter for the fence
+ *
+ * This is just a convenience function that combines drm_syncobj_find() and
+ * drm_syncobj_fence_get().
+ *
+ * Returns 0 on success or a negative error value on failure. On success @fence
+ * contains a reference to the fence, which must be released by calling
+ * dma_fence_put().
+ */
 int drm_syncobj_find_fence(struct drm_file *file_private,
 			   u32 handle,
 			   struct dma_fence **fence)
@@ -267,6 +283,12 @@ EXPORT_SYMBOL(drm_syncobj_free);
  * @out_syncobj: returned syncobj
  * @flags: DRM_SYNCOBJ_* flags
  * @fence: if non-NULL, the syncobj will represent this fence
+ *
+ * This is the first function to create a sync object. After creating, drivers
+ * probably want to make it available to userspace, either through
+ * drm_syncobj_get_handle() or drm_syncobj_get_fd().
+ *
+ * Returns 0 on success or a negative error value on failure.
  */
 int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
 		       struct dma_fence *fence)
@@ -300,6 +322,14 @@ EXPORT_SYMBOL(drm_syncobj_create);
 
 /**
  * drm_syncobj_get_handle - get a handle from a syncobj
+ * @file_private: drm file private pointer
+ * @syncobj: Sync object to export
+ * @handle: out parameter with the new handle
+ *
+ * Exports a sync object created with drm_syncobj_create() as a handle on
+ * @file_private to userspace.
+ *
+ * Returns 0 on success or a negative error value on failure.
  */
 int drm_syncobj_get_handle(struct drm_file *file_private,
 			   struct drm_syncobj *syncobj, u32 *handle)
@@ -369,6 +399,15 @@ static const struct file_operations drm_syncobj_file_fops = {
 	.release = drm_syncobj_file_release,
 };
 
+/**
+ * drm_syncobj_get_fd - get a file descriptor from a syncobj
+ * @syncobj: Sync object to export
+ * @p_fd: out parameter with the new file descriptor
+ *
+ * Exports a sync object created with drm_syncobj_create() as a file descriptor.
+ *
+ * Returns 0 on success or a negative error value on failure.
+ */
 int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd)
 {
 	struct file *file;
@@ -640,7 +679,8 @@ static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
 		container_of(cb, struct syncobj_wait_entry, syncobj_cb);
 
 	/* This happens inside the syncobj lock */
-	wait->fence = dma_fence_get(syncobj->fence);
+	wait->fence = dma_fence_get(rcu_dereference_protected(syncobj->fence,
+							      lockdep_is_held(&syncobj->lock)));
 	wake_up_process(wait->task);
 }