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, 15 insertions, 28 deletions

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)