drm: Simplify core vs. drv ioctl handling

Now that cmd_drv is gone the handling for core and driver ioctls is
mostly identical, so eliminate the duplication. Also take the
opportunity to simplify the range checks to be less cluttered.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/drm_ioctl.c

@@ -663,39 +663,30 @@ long drm_ioctl(struct file *filp,
 	int retcode = -EINVAL;
 	char stack_kdata[128];
 	char *kdata = NULL;
-	unsigned int usize, asize;
+	unsigned int usize, asize, drv_size;
 
 	dev = file_priv->minor->dev;
 
 	if (drm_device_is_unplugged(dev))
 		return -ENODEV;
 
-	if ((nr >= DRM_CORE_IOCTL_COUNT) &&
-	    ((nr < DRM_COMMAND_BASE) || (nr >= DRM_COMMAND_END)))
+	if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END) {
+		/* driver ioctl */
+		if (nr - DRM_COMMAND_BASE >= dev->driver->num_ioctls)
 			goto err_i1;
-	if ((nr >= DRM_COMMAND_BASE) && (nr < DRM_COMMAND_END) &&
-	    (nr < DRM_COMMAND_BASE + dev->driver->num_ioctls)) {
-		u32 drv_size;
 		ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
-		drv_size = _IOC_SIZE(ioctl->cmd);
-		usize = asize = _IOC_SIZE(cmd);
-		if (drv_size > asize)
-			asize = drv_size;
-		cmd = ioctl->cmd;
-	}
-	else if ((nr >= DRM_COMMAND_END) || (nr < DRM_COMMAND_BASE)) {
-		u32 drv_size;
-
+	} else {
+		/* core ioctl */
+		if (nr >= DRM_CORE_IOCTL_COUNT)
+			goto err_i1;
 		ioctl = &drm_ioctls[nr];
+	}
 
 	drv_size = _IOC_SIZE(ioctl->cmd);
 	usize = asize = _IOC_SIZE(cmd);
 	if (drv_size > asize)
 		asize = drv_size;
-
 	cmd = ioctl->cmd;
-	} else
-		goto err_i1;
 
 	DRM_DEBUG("pid=%d, dev=0x%lx, auth=%d, %s\n",
 		  task_pid_nr(current),