Re: [PATCH v3 4/4] drm/virtio: Support virtgpu exported resources

On Wed, Mar 11, 2020 at 08:20:04PM +0900, David Stevens wrote:

Add support for UUID-based resource sharing mechanism to virtgpu. This implements the new virtgpu commands and hooks them up to dma-buf's get_uuid callback.

Signed-off-by: David Stevens stevensd@chromium.org

drivers/gpu/drm/virtio/virtgpu_drv.c | 3 ++ drivers/gpu/drm/virtio/virtgpu_drv.h | 18 +++++++++ drivers/gpu/drm/virtio/virtgpu_kms.c | 4 ++ drivers/gpu/drm/virtio/virtgpu_prime.c | 41 +++++++++++++++++-- drivers/gpu/drm/virtio/virtgpu_vq.c | 55 ++++++++++++++++++++++++++ 5 files changed, 118 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.c b/drivers/gpu/drm/virtio/virtgpu_drv.c index ab4bed78e656..776e6667042e 100644 --- a/drivers/gpu/drm/virtio/virtgpu_drv.c +++ b/drivers/gpu/drm/virtio/virtgpu_drv.c @@ -165,6 +165,7 @@ static unsigned int features[] = { VIRTIO_GPU_F_VIRGL, #endif VIRTIO_GPU_F_EDID,

• VIRTIO_GPU_F_RESOURCE_UUID,

}; static struct virtio_driver virtio_gpu_driver = { .feature_table = features, @@ -202,7 +203,9 @@ static struct drm_driver driver = { .prime_handle_to_fd = drm_gem_prime_handle_to_fd, .prime_fd_to_handle = drm_gem_prime_fd_to_handle, .gem_prime_mmap = drm_gem_prime_mmap,

• .gem_prime_export = virtgpu_gem_prime_export, .gem_prime_import_sg_table = virtgpu_gem_prime_import_sg_table,

• .gem_prime_get_uuid = virtgpu_gem_prime_get_uuid,

  .gem_create_object = virtio_gpu_create_object, .fops = &virtio_gpu_driver_fops,

diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h index af9403e1cf78..fab65f0f5a4d 100644 --- a/drivers/gpu/drm/virtio/virtgpu_drv.h +++ b/drivers/gpu/drm/virtio/virtgpu_drv.h @@ -49,6 +49,10 @@ #define DRIVER_MINOR 1 #define DRIVER_PATCHLEVEL 0

+#define UUID_INITIALIZING 0 +#define UUID_INITIALIZED 1 +#define UUID_INITIALIZATION_FAILED 2

struct virtio_gpu_object_params { uint32_t format; uint32_t width; @@ -75,6 +79,9 @@ struct virtio_gpu_object {

bool dumb; bool created;

• int uuid_state;
• uuid_t uuid;

}; #define gem_to_virtio_gpu_obj(gobj) \ container_of((gobj), struct virtio_gpu_object, base.base) @@ -196,6 +203,7 @@ struct virtio_gpu_device { bool has_virgl_3d; bool has_edid; bool has_indirect;

• bool has_resource_assign_uuid;

  struct work_struct config_changed_work;

@@ -206,6 +214,8 @@ struct virtio_gpu_device { struct virtio_gpu_drv_capset *capsets; uint32_t num_capsets; struct list_head cap_cache;

• spinlock_t resource_export_lock;

};

struct virtio_gpu_fpriv { @@ -338,6 +348,10 @@ void virtio_gpu_dequeue_fence_func(struct work_struct *work); void virtio_gpu_disable_notify(struct virtio_gpu_device *vgdev); void virtio_gpu_enable_notify(struct virtio_gpu_device *vgdev);

+int +virtio_gpu_cmd_resource_assign_uuid(struct virtio_gpu_device *vgdev,

• 		    struct virtio_gpu_object_array *objs);
  

/* virtio_gpu_display.c */ void virtio_gpu_modeset_init(struct virtio_gpu_device *vgdev); void virtio_gpu_modeset_fini(struct virtio_gpu_device *vgdev); @@ -366,6 +380,10 @@ int virtio_gpu_object_create(struct virtio_gpu_device *vgdev, struct virtio_gpu_object **bo_ptr, struct virtio_gpu_fence *fence); /* virtgpu_prime.c */ +struct dma_buf *virtgpu_gem_prime_export(struct drm_gem_object *obj,

• 			 int flags);
  

+int virtgpu_gem_prime_get_uuid(struct drm_gem_object *obj,

• 	       uuid_t *uuid);
  

struct drm_gem_object *virtgpu_gem_prime_import_sg_table( struct drm_device *dev, struct dma_buf_attachment *attach, struct sg_table *sgt); diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c index 4009c2f97d08..5a2aeb6d2f35 100644 --- a/drivers/gpu/drm/virtio/virtgpu_kms.c +++ b/drivers/gpu/drm/virtio/virtgpu_kms.c @@ -134,6 +134,7 @@ int virtio_gpu_init(struct drm_device *dev) vgdev->dev = dev->dev;

spin_lock_init(&vgdev->display_info_lock);

• spin_lock_init(&vgdev->resource_export_lock); ida_init(&vgdev->ctx_id_ida); ida_init(&vgdev->resource_ida); init_waitqueue_head(&vgdev->resp_wq);

@@ -162,6 +163,9 @@ int virtio_gpu_init(struct drm_device *dev) if (virtio_has_feature(vgdev->vdev, VIRTIO_RING_F_INDIRECT_DESC)) { vgdev->has_indirect = true; }

• if (virtio_has_feature(vgdev->vdev, VIRTIO_GPU_F_RESOURCE_UUID)) {

• vgdev->has_resource_assign_uuid = true;
  

• }

Just a question: this relies on DMA bufs so I assume it is not really assumed to work when DMA API is bypassed, right? Rather than worry what does it mean, how about just disabling this feature without PLATFORM_DMA for now?

DRM_INFO("features: %cvirgl %cedid\n", vgdev->has_virgl_3d ? '+' : '-', diff --git a/drivers/gpu/drm/virtio/virtgpu_prime.c b/drivers/gpu/drm/virtio/virtgpu_prime.c index 050d24c39a8f..7c6357f59877 100644 --- a/drivers/gpu/drm/virtio/virtgpu_prime.c +++ b/drivers/gpu/drm/virtio/virtgpu_prime.c @@ -26,9 +26,44 @@

#include "virtgpu_drv.h"

-/* Empty Implementations as there should not be any other driver for a virtual

• • device that might share buffers with virtgpu
• */

+int virtgpu_gem_prime_get_uuid(struct drm_gem_object *obj,

• 	       uuid_t *uuid)
  

+{

• struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
• struct virtio_gpu_device *vgdev = obj->dev->dev_private;
• wait_event(vgdev->resp_wq, bo->uuid_state != UUID_INITIALIZING);
• if (bo->uuid_state != UUID_INITIALIZED)

• return -ENODEV;
  

• uuid_copy(uuid, &bo->uuid);
• return 0;

+}

+struct dma_buf *virtgpu_gem_prime_export(struct drm_gem_object *obj,

• 			 int flags)
  

+{

• struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
• struct virtio_gpu_device *vgdev = obj->dev->dev_private;
• struct virtio_gpu_object_array *objs;
• int ret = 0;
• if (vgdev->has_resource_assign_uuid) {

• objs = virtio_gpu_array_alloc(1);
  

• if (!objs)
  

• 	return ERR_PTR(-ENOMEM);
  

• virtio_gpu_array_add_obj(objs, &bo->base.base);
  

• ret = virtio_gpu_cmd_resource_assign_uuid(vgdev, objs);
  

• if (ret)
  

• 	return ERR_PTR(ret);
  

• } else {

• bo->uuid_state = UUID_INITIALIZATION_FAILED;
  

• }
• return drm_gem_prime_export(obj, flags);

+}

struct drm_gem_object *virtgpu_gem_prime_import_sg_table( struct drm_device *dev, struct dma_buf_attachment *attach, diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index cfe9c54f87a3..b968eaa46bb0 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -1111,3 +1111,58 @@ void virtio_gpu_cursor_ping(struct virtio_gpu_device *vgdev, memcpy(cur_p, &output->cursor, sizeof(output->cursor)); virtio_gpu_queue_cursor(vgdev, vbuf); }

+static void virtio_gpu_cmd_resource_uuid_cb(struct virtio_gpu_device *vgdev,

• 			    struct virtio_gpu_vbuffer *vbuf)
  

+{

• struct virtio_gpu_object *obj =

• gem_to_virtio_gpu_obj(vbuf->objs->objs[0]);
  

• struct virtio_gpu_resp_resource_uuid *resp =

• (struct virtio_gpu_resp_resource_uuid *)vbuf->resp_buf;
  

• uint32_t resp_type = le32_to_cpu(resp->hdr.type);
• spin_lock(&vgdev->resource_export_lock);
• WARN_ON(obj->uuid_state != UUID_INITIALIZING);
• if (resp_type == VIRTIO_GPU_RESP_OK_RESOURCE_UUID &&

• 	obj->uuid_state == UUID_INITIALIZING) {
  

• memcpy(&obj->uuid.b, resp->uuid, sizeof(obj->uuid.b));
  

• obj->uuid_state = UUID_INITIALIZED;
  

• } else {

• obj->uuid_state = UUID_INITIALIZATION_FAILED;
  

• }
• spin_unlock(&vgdev->resource_export_lock);
• wake_up_all(&vgdev->resp_wq);

+}

+int +virtio_gpu_cmd_resource_assign_uuid(struct virtio_gpu_device *vgdev,

• 		    struct virtio_gpu_object_array *objs)
  

+{

• struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(objs->objs[0]);
• struct virtio_gpu_resource_assign_uuid *cmd_p;
• struct virtio_gpu_vbuffer *vbuf;
• struct virtio_gpu_resp_resource_uuid *resp_buf;
• resp_buf = kzalloc(sizeof(*resp_buf), GFP_KERNEL);
• if (!resp_buf) {

• spin_lock(&vgdev->resource_export_lock);
  

• bo->uuid_state = UUID_INITIALIZATION_FAILED;
  

• spin_unlock(&vgdev->resource_export_lock);
  

• virtio_gpu_array_put_free(objs);
  

• return -ENOMEM;
  

• }
• cmd_p = virtio_gpu_alloc_cmd_resp(vgdev,

• virtio_gpu_cmd_resource_uuid_cb, &vbuf, sizeof(*cmd_p),
  

• sizeof(struct virtio_gpu_resp_resource_uuid), resp_buf);
  

• memset(cmd_p, 0, sizeof(*cmd_p));
• cmd_p->hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_RESOURCE_ASSIGN_UUID);
• cmd_p->resource_id = cpu_to_le32(bo->hw_res_handle);
• vbuf->objs = objs;
• virtio_gpu_queue_ctrl_buffer(vgdev, vbuf);
• return 0;

+}

2.25.1.481.gfbce0eb801-goog