drm/nouveau/nvif: allow userspace access to its own client object

Regression from "abi16: implement limited interoperability with
usif/nvif".
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nouveau_drm.h

@@ -39,6 +39,7 @@
 
 #include <nvif/client.h>
 #include <nvif/device.h>
+#include <nvif/ioctl.h>
 
 #include <drmP.h>
 
@@ -65,9 +66,10 @@ struct nouveau_drm_tile {
 };
 
 enum nouveau_drm_object_route {
-	NVDRM_OBJECT_NVIF = 0,
+	NVDRM_OBJECT_NVIF = NVIF_IOCTL_V0_OWNER_NVIF,
 	NVDRM_OBJECT_USIF,
 	NVDRM_OBJECT_ABI16,
+	NVDRM_OBJECT_ANY = NVIF_IOCTL_V0_OWNER_ANY,
 };
 
 enum nouveau_drm_notify_route {

drivers/gpu/drm/nouveau/nouveau_usif.c

@@ -313,7 +313,10 @@ usif_ioctl(struct drm_file *filp, void __user *user, u32 argc)
 	if (nvif_unpack(argv->v0, 0, 0, true)) {
 		/* block access to objects not created via this interface */
 		owner = argv->v0.owner;
-		argv->v0.owner = NVDRM_OBJECT_USIF;
+		if (argv->v0.object == 0ULL)
+			argv->v0.owner = NVDRM_OBJECT_ANY; /* except client */
+		else
+			argv->v0.owner = NVDRM_OBJECT_USIF;
 	} else
 		goto done;