drm/exynos: added a feature to get gem buffer information.

this patch adds a feature to get a gem buffer information and user application
can get the gem buffer information simply in runtime through gem handle.
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>

drivers/gpu/drm/exynos/exynos_drm_drv.c

@@ -211,6 +211,8 @@ static struct drm_ioctl_desc exynos_ioctls[] = {
 			DRM_AUTH),
 	DRM_IOCTL_DEF_DRV(EXYNOS_GEM_MMAP,
 			exynos_drm_gem_mmap_ioctl, DRM_UNLOCKED | DRM_AUTH),
+	DRM_IOCTL_DEF_DRV(EXYNOS_GEM_GET,
+			exynos_drm_gem_get_ioctl, DRM_UNLOCKED),
 	DRM_IOCTL_DEF_DRV(EXYNOS_PLANE_SET_ZPOS, exynos_plane_set_zpos_ioctl,
 			DRM_UNLOCKED | DRM_AUTH),
 	DRM_IOCTL_DEF_DRV(EXYNOS_VIDI_CONNECTION,

drivers/gpu/drm/exynos/exynos_drm_gem.c

@@ -604,6 +604,32 @@ int exynos_drm_gem_mmap_ioctl(struct drm_device *dev, void *data,
 	return 0;
 }
 
+int exynos_drm_gem_get_ioctl(struct drm_device *dev, void *data,
+				      struct drm_file *file_priv)
+{	struct exynos_drm_gem_obj *exynos_gem_obj;
+	struct drm_exynos_gem_info *args = data;
+	struct drm_gem_object *obj;
+
+	mutex_lock(&dev->struct_mutex);
+
+	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
+	if (!obj) {
+		DRM_ERROR("failed to lookup gem object.\n");
+		mutex_unlock(&dev->struct_mutex);
+		return -EINVAL;
+	}
+
+	exynos_gem_obj = to_exynos_gem_obj(obj);
+
+	args->flags = exynos_gem_obj->flags;
+	args->size = exynos_gem_obj->size;
+
+	drm_gem_object_unreference(obj);
+	mutex_unlock(&dev->struct_mutex);
+
+	return 0;
+}
+
 int exynos_drm_gem_init_object(struct drm_gem_object *obj)
 {
 	DRM_DEBUG_KMS("%s\n", __FILE__);

drivers/gpu/drm/exynos/exynos_drm_gem.h

@@ -127,6 +127,10 @@ int exynos_drm_gem_map_offset_ioctl(struct drm_device *dev, void *data,
 int exynos_drm_gem_mmap_ioctl(struct drm_device *dev, void *data,
 			      struct drm_file *file_priv);
 
+/* get buffer information to memory region allocated by gem. */
+int exynos_drm_gem_get_ioctl(struct drm_device *dev, void *data,
+				      struct drm_file *file_priv);
+
 /* initialize gem object. */
 int exynos_drm_gem_init_object(struct drm_gem_object *obj);
 

include/drm/exynos_drm.h

@@ -74,6 +74,21 @@ struct drm_exynos_gem_mmap {
 	uint64_t mapped;
 };
 
+/**
+ * A structure to gem information.
+ *
+ * @handle: a handle to gem object created.
+ * @flags: flag value including memory type and cache attribute and
+ *	this value would be set by driver.
+ * @size: size to memory region allocated by gem and this size would
+ *	be set by driver.
+ */
+struct drm_exynos_gem_info {
+	unsigned int handle;
+	unsigned int flags;
+	uint64_t size;
+};
+
 /**
  * A structure for user connection request of virtual display.
  *
@@ -113,6 +128,7 @@ enum e_drm_exynos_gem_mem_type {
 #define DRM_EXYNOS_GEM_MAP_OFFSET	0x01
 #define DRM_EXYNOS_GEM_MMAP		0x02
 /* Reserved 0x03 ~ 0x05 for exynos specific gem ioctl */
+#define DRM_EXYNOS_GEM_GET		0x04
 #define DRM_EXYNOS_PLANE_SET_ZPOS	0x06
 #define DRM_EXYNOS_VIDI_CONNECTION	0x07
 
@@ -125,6 +141,9 @@ enum e_drm_exynos_gem_mem_type {
 #define DRM_IOCTL_EXYNOS_GEM_MMAP	DRM_IOWR(DRM_COMMAND_BASE + \
 		DRM_EXYNOS_GEM_MMAP, struct drm_exynos_gem_mmap)
 
+#define DRM_IOCTL_EXYNOS_GEM_GET	DRM_IOWR(DRM_COMMAND_BASE + \
+		DRM_EXYNOS_GEM_GET,	struct drm_exynos_gem_info)
+
 #define DRM_IOCTL_EXYNOS_PLANE_SET_ZPOS	DRM_IOWR(DRM_COMMAND_BASE + \
 		DRM_EXYNOS_PLANE_SET_ZPOS, struct drm_exynos_plane_set_zpos)