drm/vgem: Convert to a struct drm_device subclass

With Laura's introduction of the fake platform device for importing
dmabuf, we add a second static that is logically tied to the vgem_device.
Convert vgem over to using the struct drm_device subclassing, so that
the platform device is stored inside its owner.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170508132228.9509-1-chris@chris-wilson.co.uk

1 files changed, 41 insertions, 22 deletions

diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c
index c9381d457a03..4b23ba049632 100644
--- a/drivers/gpu/drm/vgem/vgem_drv.c
+++ b/drivers/gpu/drm/vgem/vgem_drv.c
@@ -42,7 +42,10 @@
 #define DRIVER_MAJOR    1
 #define DRIVER_MINOR    0
 
-static struct platform_device *vgem_platform;
+static struct vgem_device {
+        struct drm_device drm;
+        struct platform_device *platform;
+} *vgem_device;
 
 static void vgem_gem_free_object(struct drm_gem_object *obj)
 {
@@ -307,7 +310,9 @@ static struct sg_table *vgem_prime_get_sg_table(struct drm_gem_object *obj)
 static struct drm_gem_object* vgem_prime_import(struct drm_device *dev,
                                                 struct dma_buf *dma_buf)
 {
-        return drm_gem_prime_import_dev(dev, dma_buf, &vgem_platform->dev);
+        struct vgem_device *vgem = container_of(dev, typeof(*vgem), drm);
+
+        return drm_gem_prime_import_dev(dev, dma_buf, &vgem->platform->dev);
 }
 
 static struct drm_gem_object *vgem_prime_import_sg_table(struct drm_device *dev,
@@ -377,8 +382,19 @@ static int vgem_prime_mmap(struct drm_gem_object *obj,
         return 0;
 }
 
+static void vgem_release(struct drm_device *dev)
+{
+        struct vgem_device *vgem = container_of(dev, typeof(*vgem), drm);
+
+        platform_device_unregister(vgem->platform);
+        drm_dev_fini(&vgem->drm);
+
+        kfree(vgem);
+}
+
 static struct drm_driver vgem_driver = {
         .driver_features                = DRIVER_GEM | DRIVER_PRIME,
+        .release                        = vgem_release,
         .open                           = vgem_open,
         .postclose                      = vgem_postclose,
         .gem_free_object_unlocked       = vgem_gem_free_object,
@@ -408,45 +424,48 @@ static struct drm_driver vgem_driver = {
         .minor  = DRIVER_MINOR,
 };
 
-static struct drm_device *vgem_device;
-
 static int __init vgem_init(void)
 {
         int ret;
 
-        vgem_device = drm_dev_alloc(&vgem_driver, NULL);
-        if (IS_ERR(vgem_device))
-                return PTR_ERR(vgem_device);
+        vgem_device = kzalloc(sizeof(*vgem_device), GFP_KERNEL);
+        if (!vgem_device)
+                return -ENOMEM;
 
-        vgem_platform = platform_device_register_simple("vgem",
-                                        -1, NULL, 0);
+        ret = drm_dev_init(&vgem_device->drm, &vgem_driver, NULL);
+        if (ret)
+                goto out_free;
 
-        if (!vgem_platform) {
+        vgem_device->platform =
+                platform_device_register_simple("vgem", -1, NULL, 0);
+        if (!vgem_device->platform) {
                 ret = -ENODEV;
-                goto out;
+                goto out_fini;
         }
 
-        dma_coerce_mask_and_coherent(&vgem_platform->dev,
-                                        DMA_BIT_MASK(64));
+        dma_coerce_mask_and_coherent(&vgem_device->platform->dev,
+                                     DMA_BIT_MASK(64));
 
-        ret  = drm_dev_register(vgem_device, 0);
+        /* Final step: expose the device/driver to userspace */
+        ret  = drm_dev_register(&vgem_device->drm, 0);
         if (ret)
-                goto out_unref;
+                goto out_unregister;
 
         return 0;
 
-out_unref:
-        platform_device_unregister(vgem_platform);
-out:
-        drm_dev_unref(vgem_device);
+out_unregister:
+        platform_device_unregister(vgem_device->platform);
+out_fini:
+        drm_dev_fini(&vgem_device->drm);
+out_free:
+        kfree(vgem_device);
         return ret;
 }
 
 static void __exit vgem_exit(void)
 {
-        platform_device_unregister(vgem_platform);
-        drm_dev_unregister(vgem_device);
-        drm_dev_unref(vgem_device);
+        drm_dev_unregister(&vgem_device->drm);
+        drm_dev_unref(&vgem_device->drm);
 }
 
 module_init(vgem_init);