drm/msm: submit support for in-fences

Signed-off-by: Rob Clark <robdclark@gmail.com>
diff --git a/drivers/gpu/drm/msm/Kconfig b/drivers/gpu/drm/msm/Kconfig
index 7c7a031..d96b2b6 100644
--- a/drivers/gpu/drm/msm/Kconfig
+++ b/drivers/gpu/drm/msm/Kconfig
@@ -11,6 +11,7 @@
 	select TMPFS
 	select QCOM_SCM
 	select SND_SOC_HDMI_CODEC if SND_SOC
+	select SYNC_FILE
 	default y
 	help
 	  DRM/KMS driver for MSM/snapdragon.
diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c
index 0b96d85..3a4a8dd 100644
--- a/drivers/gpu/drm/msm/msm_gem_submit.c
+++ b/drivers/gpu/drm/msm/msm_gem_submit.c
@@ -15,6 +15,8 @@
  * this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <linux/sync_file.h>
+
 #include "msm_drv.h"
 #include "msm_gpu.h"
 #include "msm_gem.h"
@@ -361,6 +363,7 @@
 	struct msm_file_private *ctx = file->driver_priv;
 	struct msm_gem_submit *submit;
 	struct msm_gpu *gpu = priv->gpu;
+	struct fence *in_fence = NULL;
 	unsigned i;
 	int ret;
 
@@ -394,9 +397,32 @@
 	if (ret)
 		goto out;
 
-	ret = submit_fence_sync(submit);
-	if (ret)
-		goto out;
+	if (args->flags & MSM_SUBMIT_FENCE_FD_IN) {
+		in_fence = sync_file_get_fence(args->fence_fd);
+
+		if (!in_fence) {
+			ret = -EINVAL;
+			goto out;
+		}
+
+		/* TODO if we get an array-fence due to userspace merging multiple
+		 * fences, we need a way to determine if all the backing fences
+		 * are from our own context..
+		 */
+
+		if (in_fence->context != gpu->fctx->context) {
+			ret = fence_wait(in_fence, true);
+			if (ret)
+				goto out;
+		}
+
+	}
+
+	if (!(args->fence & MSM_SUBMIT_NO_IMPLICIT)) {
+		ret = submit_fence_sync(submit);
+		if (ret)
+			goto out;
+	}
 
 	ret = submit_pin_objects(submit);
 	if (ret)
@@ -467,6 +493,8 @@
 	args->fence = submit->fence->seqno;
 
 out:
+	if (in_fence)
+		fence_put(in_fence);
 	submit_cleanup(submit);
 	if (ret)
 		msm_gem_submit_free(submit);