drm/nouveau/core/client: allow creation of subclients

We want a supervisor client of NVKM (such as the DRM) to be able to
allow sharing of resources (such as memory objects) between clients.

To allow this, the supervisor creates all its clients as children of
itself, and will use an upcoming ioctl to permit sharing.

Currently it's not possible for indirect clients to use subclients.
Supporting this will require an additional field in the main ioctl.
This isn't important currently, but will need to be fixed for virt.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 48 insertions, 2 deletions

diff --git a/drivers/gpu/drm/nouveau/nvkm/core/client.c b/drivers/gpu/drm/nouveau/nvkm/core/client.c
index 4e2730cb1fec..0d3a896892b4 100644
--- a/drivers/gpu/drm/nouveau/nvkm/core/client.c
+++ b/drivers/gpu/drm/nouveau/nvkm/core/client.c
@@ -31,9 +31,41 @@
 #include <nvif/if0000.h>
 #include <nvif/unpack.h>
 
-static const struct nvkm_sclass
+static int
+nvkm_uclient_new(const struct nvkm_oclass *oclass, void *argv, u32 argc,
+		 struct nvkm_object **pobject)
+{
+	union {
+		struct nvif_client_v0 v0;
+	} *args = argv;
+	struct nvkm_client *client;
+	int ret = -ENOSYS;
+
+	if (!(ret = nvif_unpack(ret, &argv, &argc, args->v0, 0, 0, false))){
+		args->v0.name[sizeof(args->v0.name) - 1] = 0;
+		ret = nvkm_client_new(args->v0.name, args->v0.device, NULL,
+				      NULL, oclass->client->ntfy, &client);
+		if (ret)
+			return ret;
+	} else
+		return ret;
+
+	client->object.client = oclass->client;
+	client->object.handle = oclass->handle;
+	client->object.route  = oclass->route;
+	client->object.token  = oclass->token;
+	client->object.object = oclass->object;
+	client->debug = oclass->client->debug;
+	*pobject = &client->object;
+	return 0;
+}
+
+const struct nvkm_sclass
 nvkm_uclient_sclass = {
 	.oclass = NVIF_CLASS_CLIENT,
+	.minver = 0,
+	.maxver = 0,
+	.ctor = nvkm_uclient_new,
 };
 
 struct nvkm_client_notify {
@@ -143,6 +175,19 @@ nvkm_client_notify_new(struct nvkm_object *object,
 	return ret;
 }
 
+static const struct nvkm_object_func nvkm_client;
+struct nvkm_client *
+nvkm_client_search(struct nvkm_client *client, u64 handle)
+{
+	struct nvkm_object *object;
+
+	object = nvkm_object_search(client, handle, &nvkm_client);
+	if (IS_ERR(object))
+		return (void *)object;
+
+	return nvkm_client(object);
+}
+
 static int
 nvkm_client_mthd_devlist(struct nvkm_client *client, void *data, u32 size)
 {
@@ -196,7 +241,8 @@ nvkm_client_child_get(struct nvkm_object *object, int index,
 	const struct nvkm_sclass *sclass;
 
 	switch (index) {
-	case 0: sclass = &nvkm_udevice_sclass; break;
+	case 0: sclass = &nvkm_uclient_sclass; break;
+	case 1: sclass = &nvkm_udevice_sclass; break;
 	default:
 		return -EINVAL;
 	}