BACKPORT: drm/virtio: implement context init: support init ioctlandroid-u-beta-4_r0.7android-u-beta-4_r0.5android-u-beta-4_r0.4android-u-beta-4_r0.3android-u-beta-4_r0.2android-u-beta-4_r0.1android-u-beta-3_r0.3android-u-beta-3_r0.2android-u-beta-2.1_r0.4android-u-beta-2.1_r0.3android-u-beta-2.1_r0.2android-gs-tangorpro-5.10-u-beta4android-gs-raviole-5.10-u-beta4android-gs-raviole-5.10-u-beta3android-gs-raviole-5.10-u-beta2android-gs-pantah-5.10-u-beta4android-gs-pantah-5.10-u-beta2android-gs-lynx-5.10-u-beta4android-gs-felix-5.10-u-beta4android-gs-bluejay-5.10-u-beta4android-gs-bluejay-5.10-u-beta3android-gs-bluejay-5.10-u-beta2

This implements the context initialization ioctl.  A list of params
is passed in by userspace, and kernel driver validates them.  The
only currently supported param is VIRTGPU_CONTEXT_PARAM_CAPSET_ID.

If the context has already been initialized, -EEXIST is returned.
This happens after Linux userspace does dumb_create + followed by
opening the Mesa virgl driver with the same virtgpu instance.

However, for most applications, 3D contexts will be explicitly
initialized when the feature is available.

Signed-off-by: Anthoine Bourgeois <anthoine.bourgeois@gmail.com>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-6-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

Bug: 278150168
Change-Id: I3dd83a1765fd26f40e86e3b25b597e946a83da9f
(cherry picked from commit 4fb530e5caf7cb666948db65f245b350ce520436)
[kaiyili: Reslved merge conflicts in virtio_gpu/{virtgpu_drv.h,virtgpu_ioctl.c}]
Signed-off-by: Kaiyi Li <kaiyili@google.com>

2 files changed, 25 insertions, 13 deletions

diff --git a/virtio_gpu/virtgpu_drv.h b/virtio_gpu/virtgpu_drv.h
index 0a6d8b9..ac6e7df 100644
--- a/virtio_gpu/virtgpu_drv.h
+++ b/virtio_gpu/virtgpu_drv.h
@@ -273,7 +273,7 @@ struct virtio_gpu_fpriv {
 	struct mutex context_lock;
 };
 
-/* virtio_ioctl.c */
+/* virtgpu_ioctl.c */
 #define DRM_VIRTIO_NUM_IOCTLS 12
 extern struct drm_ioctl_desc virtio_gpu_ioctls[DRM_VIRTIO_NUM_IOCTLS];
 void virtio_gpu_create_context(struct drm_device *dev, struct drm_file *file);
diff --git a/virtio_gpu/virtgpu_ioctl.c b/virtio_gpu/virtgpu_ioctl.c
index 3514c90..2d8f9bc 100644
--- a/virtio_gpu/virtgpu_ioctl.c
+++ b/virtio_gpu/virtgpu_ioctl.c
@@ -713,7 +713,7 @@ static int virtio_gpu_context_init_ioctl(struct drm_device *dev,
 	int ret = 0;
 	uint32_t num_params, i, param, value;
 	size_t len;
-	struct drm_virtgpu_context_set_param *ctx_set_params;
+	struct drm_virtgpu_context_set_param *ctx_set_params = NULL;
 	struct virtio_gpu_device *vgdev = dev->dev_private;
 	struct virtio_gpu_fpriv *vfpriv = file->driver_priv;
 	struct drm_virtgpu_context_init *args = data;
@@ -746,31 +746,42 @@ static int virtio_gpu_context_init_ioctl(struct drm_device *dev,
 
 		switch (param) {
 		case VIRTGPU_CONTEXT_PARAM_CAPSET_ID:
-			if (value > MAX_CAPSET_ID)
-				return -EINVAL;
+			if (value > MAX_CAPSET_ID) {
+				ret = -EINVAL;
+				goto out_unlock;
+			}
 
-			if ((vgdev->capset_id_mask & (1 << value)) == 0)
-				return -EINVAL;
+			if ((vgdev->capset_id_mask & (1 << value)) == 0) {
+				ret = -EINVAL;
+				goto out_unlock;
+			}
 
 			/* Context capset ID already set */
 			if (vfpriv->context_init &
-			    VIRTIO_GPU_CONTEXT_INIT_CAPSET_ID_MASK)
-				return -EINVAL;
+			    VIRTIO_GPU_CONTEXT_INIT_CAPSET_ID_MASK) {
+				ret = -EINVAL;
+				goto out_unlock;
+			}
 
 			vfpriv->context_init |= value;
 			break;
 		case VIRTGPU_CONTEXT_PARAM_NUM_FENCE_CONTEXTS:
-			if (vfpriv->base_fence_ctx)
-				return -EINVAL;
+			if (vfpriv->base_fence_ctx) {
+				ret = -EINVAL;
+				goto out_unlock;
+			}
 
-			if (value > MAX_FENCE_CONTEXTS)
-				return -EINVAL;
+			if (value > MAX_FENCE_CONTEXTS) {
+				ret = -EINVAL;
+				goto out_unlock;
+			}
 
 			vfpriv->base_fence_ctx = dma_fence_context_alloc(value);
 			vfpriv->num_fence_contexts = value;
 			break;
 		default:
-			return -EINVAL;
+			ret = -EINVAL;
+			goto out_unlock;
 		}
 	}
 
@@ -779,6 +790,7 @@ static int virtio_gpu_context_init_ioctl(struct drm_device *dev,
 
 out_unlock:
 	mutex_unlock(&vfpriv->context_lock);
+	kfree(ctx_set_params);
 	return ret;
 }