drm/vmwgfx: Implement DRIVER_GEM

This is initial change adding support for DRIVER_GEM to vmwgfx. vmwgfx
was written before GEM and has always used TTM. Over the years the
TTM buffers started inherting from GEM objects but vmwgfx never
implemented GEM making it quite awkward. We were directly setting
variables in GEM objects to not make DRM crash.

This change brings vmwgfx inline with other DRM drivers and allows us
to use a lot of DRM helpers which have depended on drivers with GEM
support.

Due to historical reasons vmwgfx splits the idea of a buffer and surface
which makes it a littly tricky since either one can be used in most
of our ioctl's which take user space handles. For now our BO's are
GEM objects and our surfaces are opaque objects which are backed by
GEM objects. In the future I'd like to combine those into a single
BO but we don't want to break any of our existing ioctl's so it will
take time to do it in a non-destructive way.

Signed-off-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Martin Krastev <krastevm@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211206172620.3139754-5-zack@kde.org

1 files changed, 3 insertions, 29 deletions

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
index 40dc99337d5b..b4bbb5c47bdd 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -843,8 +843,6 @@ static void vmw_framebuffer_surface_destroy(struct drm_framebuffer *framebuffer)
 
 	drm_framebuffer_cleanup(framebuffer);
 	vmw_surface_unreference(&vfbs->surface);
-	if (vfbs->base.user_obj)
-		ttm_base_object_unref(&vfbs->base.user_obj);
 
 	kfree(vfbs);
 }
@@ -996,8 +994,6 @@ static void vmw_framebuffer_bo_destroy(struct drm_framebuffer *framebuffer)
 
 	drm_framebuffer_cleanup(framebuffer);
 	vmw_bo_unreference(&vfbd->buffer);
-	if (vfbd->base.user_obj)
-		ttm_base_object_unref(&vfbd->base.user_obj);
 
 	kfree(vfbd);
 }
@@ -1251,6 +1247,7 @@ static int vmw_kms_new_framebuffer_bo(struct vmw_private *dev_priv,
 		goto out_err1;
 	}
 
+	vfbd->base.base.obj[0] = &bo->base.base;
 	drm_helper_mode_fill_fb_struct(dev, &vfbd->base.base, mode_cmd);
 	vfbd->base.bo = true;
 	vfbd->buffer = vmw_bo_reference(bo);
@@ -1368,34 +1365,13 @@ static struct drm_framebuffer *vmw_kms_fb_create(struct drm_device *dev,
 						 const struct drm_mode_fb_cmd2 *mode_cmd)
 {
 	struct vmw_private *dev_priv = vmw_priv(dev);
-	struct ttm_object_file *tfile = vmw_fpriv(file_priv)->tfile;
 	struct vmw_framebuffer *vfb = NULL;
 	struct vmw_surface *surface = NULL;
 	struct vmw_buffer_object *bo = NULL;
-	struct ttm_base_object *user_obj;
 	int ret;
 
-	/*
-	 * Take a reference on the user object of the resource
-	 * backing the kms fb. This ensures that user-space handle
-	 * lookups on that resource will always work as long as
-	 * it's registered with a kms framebuffer. This is important,
-	 * since vmw_execbuf_process identifies resources in the
-	 * command stream using user-space handles.
-	 */
-
-	user_obj = ttm_base_object_lookup(tfile, mode_cmd->handles[0]);
-	if (unlikely(user_obj == NULL)) {
-		DRM_ERROR("Could not locate requested kms frame buffer.\n");
-		return ERR_PTR(-ENOENT);
-	}
-
-	/**
-	 * End conditioned code.
-	 */
-
 	/* returns either a bo or surface */
-	ret = vmw_user_lookup_handle(dev_priv, tfile,
+	ret = vmw_user_lookup_handle(dev_priv, file_priv,
 				     mode_cmd->handles[0],
 				     &surface, &bo);
 	if (ret)
@@ -1428,10 +1404,8 @@ err_out:
 
 	if (ret) {
 		DRM_ERROR("failed to create vmw_framebuffer: %i\n", ret);
-		ttm_base_object_unref(&user_obj);
 		return ERR_PTR(ret);
-	} else
-		vfb->user_obj = user_obj;
+	}
 
 	return &vfb->base;
 }