[PATCH 1/4] drm/atomic: integrate modeset lock with private objects

[Rob Clark]

Follow the same pattern of locking as with other state objects.  This
avoids boilerplate in the driver.

Signed-off-by: Rob Clark <robdclark at gmail.com>
---
 drivers/gpu/drm/drm_atomic.c | 9 ++++++++-
 include/drm/drm_atomic.h     | 5 +++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index fc8c4da409ff..004e621ab307 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -1078,6 +1078,8 @@ drm_atomic_private_obj_init(struct drm_private_obj *obj,
 {
 	memset(obj, 0, sizeof(*obj));
 
+	drm_modeset_lock_init(&obj->lock);
+
 	obj->state = state;
 	obj->funcs = funcs;
 }
@@ -1093,6 +1095,7 @@ void
 drm_atomic_private_obj_fini(struct drm_private_obj *obj)
 {
 	obj->funcs->atomic_destroy_state(obj, obj->state);
+	drm_modeset_lock_fini(&obj->lock);
 }
 EXPORT_SYMBOL(drm_atomic_private_obj_fini);
 
@@ -1113,7 +1116,7 @@ struct drm_private_state *
 drm_atomic_get_private_obj_state(struct drm_atomic_state *state,
 				 struct drm_private_obj *obj)
 {
-	int index, num_objs, i;
+	int index, num_objs, i, ret;
 	size_t size;
 	struct __drm_private_objs_state *arr;
 	struct drm_private_state *obj_state;
@@ -1122,6 +1125,10 @@ drm_atomic_get_private_obj_state(struct drm_atomic_state *state,
 		if (obj == state->private_objs[i].ptr)
 			return state->private_objs[i].state;
 
+	ret = drm_modeset_lock(&obj->lock, state->acquire_ctx);
+	if (ret)
+		return ERR_PTR(ret);
+
 	num_objs = state->num_private_objs + 1;
 	size = sizeof(*state->private_objs) * num_objs;
 	arr = krealloc(state->private_objs, size, GFP_KERNEL);
diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
index 09076a625637..9ae53b73c9d2 100644
--- a/include/drm/drm_atomic.h
+++ b/include/drm/drm_atomic.h
@@ -218,6 +218,11 @@ struct drm_private_state_funcs {
  * &drm_modeset_lock is required to duplicate and update this object's state.
  */
 struct drm_private_obj {
+	/**
+	 * @lock: Modeset lock to protect the state object.
+	 */
+	struct drm_modeset_lock lock;
+
 	/**
 	 * @state: Current atomic state for this driver private object.
 	 */
-- 
2.14.3