Commit 4fb530e5 authored by Anthoine Bourgeois's avatar Anthoine Bourgeois Committed by Gerd Hoffmann
Browse files

drm/virtio: implement context init: support init ioctl 



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: default avatarAnthoine Bourgeois <anthoine.bourgeois@gmail.com>
Acked-by: default avatarLingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-6-gurchetansingh@chromium.org


Signed-off-by: default avatarGerd Hoffmann <kraxel@redhat.com>
parent 6198770a

drivers/gpu/drm/virtio/virtgpu_drv.h

+4 −2
Original line number Diff line number Diff line
@@ -259,12 +259,13 @@ struct virtio_gpu_device { 


struct virtio_gpu_fpriv {

	uint32_t ctx_id;

	uint32_t context_init;

	bool context_created;

	struct mutex context_lock;

};



/* virtgpu_ioctl.c */

#define DRM_VIRTIO_NUM_IOCTLS 11

#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);
@@ -342,7 +343,8 @@ int virtio_gpu_cmd_get_capset(struct virtio_gpu_device *vgdev, 
			      struct virtio_gpu_drv_cap_cache **cache_p);

int virtio_gpu_cmd_get_edids(struct virtio_gpu_device *vgdev);

void virtio_gpu_cmd_context_create(struct virtio_gpu_device *vgdev, uint32_t id,

				   uint32_t nlen, const char *name);

				   uint32_t context_init, uint32_t nlen,

				   const char *name);

void virtio_gpu_cmd_context_destroy(struct virtio_gpu_device *vgdev,

				    uint32_t id);

void virtio_gpu_cmd_context_attach_resource(struct virtio_gpu_device *vgdev,

drivers/gpu/drm/virtio/virtgpu_ioctl.c

+91 −5
Original line number Diff line number Diff line
@@ -38,20 +38,30 @@ 
				    VIRTGPU_BLOB_FLAG_USE_SHAREABLE | \

				    VIRTGPU_BLOB_FLAG_USE_CROSS_DEVICE)



/* Must be called with &virtio_gpu_fpriv.struct_mutex held. */

static void virtio_gpu_create_context_locked(struct virtio_gpu_device *vgdev,

					     struct virtio_gpu_fpriv *vfpriv)

{

	char dbgname[TASK_COMM_LEN];



	get_task_comm(dbgname, current);

	virtio_gpu_cmd_context_create(vgdev, vfpriv->ctx_id,

				      vfpriv->context_init, strlen(dbgname),

				      dbgname);



	vfpriv->context_created = true;

}



void virtio_gpu_create_context(struct drm_device *dev, struct drm_file *file)

{

	struct virtio_gpu_device *vgdev = dev->dev_private;

	struct virtio_gpu_fpriv *vfpriv = file->driver_priv;

	char dbgname[TASK_COMM_LEN];



	mutex_lock(&vfpriv->context_lock);

	if (vfpriv->context_created)

		goto out_unlock;



	get_task_comm(dbgname, current);

	virtio_gpu_cmd_context_create(vgdev, vfpriv->ctx_id,

				      strlen(dbgname), dbgname);

	vfpriv->context_created = true;

	virtio_gpu_create_context_locked(vgdev, vfpriv);



out_unlock:

	mutex_unlock(&vfpriv->context_lock);
@@ -662,6 +672,79 @@ static int virtio_gpu_resource_create_blob_ioctl(struct drm_device *dev, 
	return 0;

}



static int virtio_gpu_context_init_ioctl(struct drm_device *dev,

					 void *data, struct drm_file *file)

{

	int ret = 0;

	uint32_t num_params, i, param, value;

	size_t len;

	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;



	num_params = args->num_params;

	len = num_params * sizeof(struct drm_virtgpu_context_set_param);



	if (!vgdev->has_context_init || !vgdev->has_virgl_3d)

		return -EINVAL;



	/* Number of unique parameters supported at this time. */

	if (num_params > 1)

		return -EINVAL;



	ctx_set_params = memdup_user(u64_to_user_ptr(args->ctx_set_params),

				     len);



	if (IS_ERR(ctx_set_params))

		return PTR_ERR(ctx_set_params);



	mutex_lock(&vfpriv->context_lock);

	if (vfpriv->context_created) {

		ret = -EEXIST;

		goto out_unlock;

	}



	for (i = 0; i < num_params; i++) {

		param = ctx_set_params[i].param;

		value = ctx_set_params[i].value;



		switch (param) {

		case VIRTGPU_CONTEXT_PARAM_CAPSET_ID:

			if (value > MAX_CAPSET_ID) {

				ret = -EINVAL;

				goto out_unlock;

			}



			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) {

				ret = -EINVAL;

				goto out_unlock;

			}



			vfpriv->context_init |= value;

			break;

		default:

			ret = -EINVAL;

			goto out_unlock;

		}

	}



	virtio_gpu_create_context_locked(vgdev, vfpriv);

	virtio_gpu_notify(vgdev);



out_unlock:

	mutex_unlock(&vfpriv->context_lock);

	kfree(ctx_set_params);

	return ret;

}



struct drm_ioctl_desc virtio_gpu_ioctls[DRM_VIRTIO_NUM_IOCTLS] = {

	DRM_IOCTL_DEF_DRV(VIRTGPU_MAP, virtio_gpu_map_ioctl,

			  DRM_RENDER_ALLOW),
@@ -698,4 +781,7 @@ struct drm_ioctl_desc virtio_gpu_ioctls[DRM_VIRTIO_NUM_IOCTLS] = { 
	DRM_IOCTL_DEF_DRV(VIRTGPU_RESOURCE_CREATE_BLOB,

			  virtio_gpu_resource_create_blob_ioctl,

			  DRM_RENDER_ALLOW),



	DRM_IOCTL_DEF_DRV(VIRTGPU_CONTEXT_INIT, virtio_gpu_context_init_ioctl,

			  DRM_RENDER_ALLOW),

};

drivers/gpu/drm/virtio/virtgpu_vq.c

+3 −1
Original line number Diff line number Diff line
@@ -911,7 +911,8 @@ int virtio_gpu_cmd_get_edids(struct virtio_gpu_device *vgdev) 
}



void virtio_gpu_cmd_context_create(struct virtio_gpu_device *vgdev, uint32_t id,

				   uint32_t nlen, const char *name)

				   uint32_t context_init, uint32_t nlen,

				   const char *name)

{

	struct virtio_gpu_ctx_create *cmd_p;

	struct virtio_gpu_vbuffer *vbuf;
@@ -922,6 +923,7 @@ void virtio_gpu_cmd_context_create(struct virtio_gpu_device *vgdev, uint32_t id, 
	cmd_p->hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_CTX_CREATE);

	cmd_p->hdr.ctx_id = cpu_to_le32(id);

	cmd_p->nlen = cpu_to_le32(nlen);

	cmd_p->context_init = cpu_to_le32(context_init);

	strncpy(cmd_p->debug_name, name, sizeof(cmd_p->debug_name) - 1);

	cmd_p->debug_name[sizeof(cmd_p->debug_name) - 1] = 0;

	virtio_gpu_queue_ctrl_buffer(vgdev, vbuf);