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>

3 files changed, 74 insertions, 28 deletions

diff --git a/drivers/gpu/drm/nouveau/nvif/Kbuild b/drivers/gpu/drm/nouveau/nvif/Kbuild
index ff8ed3a04d06..067b5e9f5ec1 100644
--- a/drivers/gpu/drm/nouveau/nvif/Kbuild
+++ b/drivers/gpu/drm/nouveau/nvif/Kbuild
@@ -1,4 +1,5 @@
 nvif-y := nvif/object.o
 nvif-y += nvif/client.o
 nvif-y += nvif/device.o
+nvif-y += nvif/driver.o
 nvif-y += nvif/notify.o
diff --git a/drivers/gpu/drm/nouveau/nvif/client.c b/drivers/gpu/drm/nouveau/nvif/client.c
index ad1307b6f783..12db54965c20 100644
--- a/drivers/gpu/drm/nouveau/nvif/client.c
+++ b/drivers/gpu/drm/nouveau/nvif/client.c
@@ -26,6 +26,9 @@
 #include <nvif/driver.h>
 #include <nvif/ioctl.h>
 
+#include <nvif/class.h>
+#include <nvif/if0000.h>
+
 int
 nvif_client_ioctl(struct nvif_client *client, void *data, u32 size)
 {
@@ -55,29 +58,21 @@ nvif_client_fini(struct nvif_client *client)
 	}
 }
 
-static const struct nvif_driver *
-nvif_drivers[] = {
-#ifdef __KERNEL__
-	&nvif_driver_nvkm,
-#else
-	&nvif_driver_drm,
-	&nvif_driver_lib,
-	&nvif_driver_null,
-#endif
-	NULL
-};
-
 int
-nvif_client_init(const char *driver, const char *name, u64 device,
-		 const char *cfg, const char *dbg, struct nvif_client *client)
+nvif_client_init(struct nvif_client *parent, const char *name, u64 device,
+		 struct nvif_client *client)
 {
+	struct nvif_client_v0 args = { .device = device };
 	struct {
 		struct nvif_ioctl_v0 ioctl;
 		struct nvif_ioctl_nop_v0 nop;
-	} args = {};
-	int ret, i;
+	} nop = {};
+	int ret;
 
-	ret = nvif_object_init(NULL, 0, 0, NULL, 0, &client->object);
+	strncpy(args.name, name, sizeof(args.name));
+	ret = nvif_object_init(parent != client ? &parent->object : NULL,
+			       0, NVIF_CLASS_CLIENT, &args, sizeof(args),
+			       &client->object);
 	if (ret)
 		return ret;
 
@@ -85,19 +80,11 @@ nvif_client_init(const char *driver, const char *name, u64 device,
 	client->object.handle = ~0;
 	client->route = NVIF_IOCTL_V0_ROUTE_NVIF;
 	client->super = true;
-
-	for (i = 0, ret = -EINVAL; (client->driver = nvif_drivers[i]); i++) {
-		if (!driver || !strcmp(client->driver->name, driver)) {
-			ret = client->driver->init(name, device, cfg, dbg,
-						  &client->object.priv);
-			if (!ret || driver)
-				break;
-		}
-	}
+	client->driver = parent->driver;
 
 	if (ret == 0) {
-		ret = nvif_client_ioctl(client, &args, sizeof(args));
-		client->version = args.nop.version;
+		ret = nvif_client_ioctl(client, &nop, sizeof(nop));
+		client->version = nop.nop.version;
 	}
 
 	if (ret)
diff --git a/drivers/gpu/drm/nouveau/nvif/driver.c b/drivers/gpu/drm/nouveau/nvif/driver.c
new file mode 100644
index 000000000000..701330956e33
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nvif/driver.c
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2016 Red Hat Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: Ben Skeggs
+ */
+#include <nvif/driver.h>
+#include <nvif/client.h>
+
+static const struct nvif_driver *
+nvif_driver[] = {
+#ifdef __KERNEL__
+	&nvif_driver_nvkm,
+#else
+	&nvif_driver_drm,
+	&nvif_driver_lib,
+	&nvif_driver_null,
+#endif
+	NULL
+};
+
+int
+nvif_driver_init(const char *drv, const char *cfg, const char *dbg,
+		 const char *name, u64 device, struct nvif_client *client)
+{
+	int ret = -EINVAL, i;
+
+	for (i = 0; (client->driver = nvif_driver[i]); i++) {
+		if (!drv || !strcmp(client->driver->name, drv)) {
+			ret = client->driver->init(name, device, cfg, dbg,
+						   &client->object.priv);
+			if (ret == 0)
+				break;
+			client->driver->fini(client->object.priv);
+		}
+	}
+
+	if (ret == 0)
+		ret = nvif_client_init(client, name, device, client);
+	return ret;
+}