drm/msm: submit support for out-fences

Signed-off-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/msm/msm_gem_submit.c

@@ -364,6 +364,8 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 	struct msm_gem_submit *submit;
 	struct msm_gpu *gpu = priv->gpu;
 	struct fence *in_fence = NULL;
+	struct sync_file *sync_file = NULL;
+	int out_fence_fd = -1;
 	unsigned i;
 	int ret;
 
@@ -383,6 +385,14 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 	if (ret)
 		return ret;
 
+	if (args->flags & MSM_SUBMIT_FENCE_FD_OUT) {
+		out_fence_fd = get_unused_fd_flags(O_CLOEXEC);
+		if (out_fence_fd < 0) {
+			ret = out_fence_fd;
+			goto out_unlock;
+		}
+	}
+
 	submit = submit_create(dev, gpu, args->nr_bos, args->nr_cmds);
 	if (!submit) {
 		ret = -ENOMEM;
@@ -495,10 +505,23 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 		goto out;
 	}
 
+	if (args->flags & MSM_SUBMIT_FENCE_FD_OUT) {
+		sync_file = sync_file_create(submit->fence);
+		if (!sync_file) {
+			ret = -ENOMEM;
+			goto out;
+		}
+	}
+
 	msm_gpu_submit(gpu, submit, ctx);
 
 	args->fence = submit->fence->seqno;
 
+	if (args->flags & MSM_SUBMIT_FENCE_FD_OUT) {
+		fd_install(out_fence_fd, sync_file->file);
+		args->fence_fd = out_fence_fd;
+	}
+
 out:
 	if (in_fence)
 		fence_put(in_fence);
@@ -506,6 +529,8 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 	if (ret)
 		msm_gem_submit_free(submit);
 out_unlock:
+	if (ret && (out_fence_fd >= 0))
+		put_unused_fd(out_fence_fd);
 	mutex_unlock(&dev->struct_mutex);
 	return ret;
 }

include/uapi/drm/msm_drm.h

@@ -187,9 +187,11 @@ struct drm_msm_gem_submit_bo {
 /* Valid submit ioctl flags: */
 #define MSM_SUBMIT_NO_IMPLICIT   0x80000000 /* disable implicit sync */
 #define MSM_SUBMIT_FENCE_FD_IN   0x40000000 /* enable input fence_fd */
+#define MSM_SUBMIT_FENCE_FD_OUT  0x20000000 /* enable output fence_fd */
 #define MSM_SUBMIT_FLAGS                ( \
 		MSM_SUBMIT_NO_IMPLICIT   | \
 		MSM_SUBMIT_FENCE_FD_IN   | \
+		MSM_SUBMIT_FENCE_FD_OUT  | \
 		0)
 
 /* Each cmdstream submit consists of a table of buffers involved, and
@@ -203,7 +205,7 @@ struct drm_msm_gem_submit {
 	__u32 nr_cmds;        /* in, number of submit_cmd's */
 	__u64 __user bos;     /* in, ptr to array of submit_bo's */
 	__u64 __user cmds;    /* in, ptr to array of submit_cmd's */
-	__s32 fence_fd;       /* in/out fence fd (see MSM_SUBMIT_FENCE_FD_IN) */
+	__s32 fence_fd;       /* in/out fence fd (see MSM_SUBMIT_FENCE_FD_IN/OUT) */
 };
 
 /* The normal way to synchronize with the GPU is just to CPU_PREP on