drm/nouveau: expose the full object/event interfaces to userspace

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_usif.c b/drivers/gpu/drm/nouveau/nouveau_usif.c
new file mode 100644
index 0000000..cb1182d
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nouveau_usif.c
@@ -0,0 +1,384 @@
+/*
+ * Copyright 2014 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 <bskeggs@redhat.com>
+ */
+
+#include "nouveau_drm.h"
+#include "nouveau_usif.h"
+
+#include <nvif/notify.h>
+#include <nvif/unpack.h>
+#include <nvif/client.h>
+#include <nvif/event.h>
+#include <nvif/ioctl.h>
+
+struct usif_notify_p {
+	struct drm_pending_event base;
+	struct {
+		struct drm_event base;
+		u8 data[];
+	} e;
+};
+
+struct usif_notify {
+	struct list_head head;
+	atomic_t enabled;
+	u32 handle;
+	u16 reply;
+	u8  route;
+	u64 token;
+	struct usif_notify_p *p;
+};
+
+static inline struct usif_notify *
+usif_notify_find(struct drm_file *filp, u32 handle)
+{
+	struct nouveau_cli *cli = nouveau_cli(filp);
+	struct usif_notify *ntfy;
+	list_for_each_entry(ntfy, &cli->notifys, head) {
+		if (ntfy->handle == handle)
+			return ntfy;
+	}
+	return NULL;
+}
+
+static inline void
+usif_notify_dtor(struct usif_notify *ntfy)
+{
+	list_del(&ntfy->head);
+	kfree(ntfy);
+}
+
+int
+usif_notify(const void *header, u32 length, const void *data, u32 size)
+{
+	struct usif_notify *ntfy = NULL;
+	const union {
+		struct nvif_notify_rep_v0 v0;
+	} *rep = header;
+	struct drm_device *dev;
+	struct drm_file *filp;
+	unsigned long flags;
+
+	if (length == sizeof(rep->v0) && rep->v0.version == 0) {
+		if (WARN_ON(!(ntfy = (void *)(unsigned long)rep->v0.token)))
+			return NVIF_NOTIFY_DROP;
+		BUG_ON(rep->v0.route != NVDRM_NOTIFY_USIF);
+	} else
+	if (WARN_ON(1))
+		return NVIF_NOTIFY_DROP;
+
+	if (WARN_ON(!ntfy->p || ntfy->reply != (length + size)))
+		return NVIF_NOTIFY_DROP;
+	filp = ntfy->p->base.file_priv;
+	dev = filp->minor->dev;
+
+	memcpy(&ntfy->p->e.data[0], header, length);
+	memcpy(&ntfy->p->e.data[length], data, size);
+	switch (rep->v0.version) {
+	case 0: {
+		struct nvif_notify_rep_v0 *rep = (void *)ntfy->p->e.data;
+		rep->route = ntfy->route;
+		rep->token = ntfy->token;
+	}
+		break;
+	default:
+		BUG_ON(1);
+		break;
+	}
+
+	spin_lock_irqsave(&dev->event_lock, flags);
+	if (!WARN_ON(filp->event_space < ntfy->p->e.base.length)) {
+		list_add_tail(&ntfy->p->base.link, &filp->event_list);
+		filp->event_space -= ntfy->p->e.base.length;
+	}
+	wake_up_interruptible(&filp->event_wait);
+	spin_unlock_irqrestore(&dev->event_lock, flags);
+	atomic_set(&ntfy->enabled, 0);
+	return NVIF_NOTIFY_DROP;
+}
+
+static int
+usif_notify_new(struct drm_file *f, void *data, u32 size, void *argv, u32 argc)
+{
+	struct nouveau_cli *cli = nouveau_cli(f);
+	struct nvif_client *client = &cli->base;
+	union {
+		struct nvif_ioctl_ntfy_new_v0 v0;
+	} *args = data;
+	union {
+		struct nvif_notify_req_v0 v0;
+	} *req;
+	struct usif_notify *ntfy;
+	int ret;
+
+	if (nvif_unpack(args->v0, 0, 0, true)) {
+		if (usif_notify_find(f, args->v0.index))
+			return -EEXIST;
+	} else
+		return ret;
+	req = data;
+
+	if (!(ntfy = kmalloc(sizeof(*ntfy), GFP_KERNEL)))
+		return -ENOMEM;
+	atomic_set(&ntfy->enabled, 0);
+
+	if (nvif_unpack(req->v0, 0, 0, true)) {
+		ntfy->reply = sizeof(struct nvif_notify_rep_v0) + req->v0.reply;
+		ntfy->route = req->v0.route;
+		ntfy->token = req->v0.token;
+		req->v0.route = NVDRM_NOTIFY_USIF;
+		req->v0.token = (unsigned long)(void *)ntfy;
+		ret = nvif_client_ioctl(client, argv, argc);
+		req->v0.token = ntfy->token;
+		req->v0.route = ntfy->route;
+		ntfy->handle = args->v0.index;
+	}
+
+	if (ret == 0)
+		list_add(&ntfy->head, &cli->notifys);
+	if (ret)
+		kfree(ntfy);
+	return ret;
+}
+
+static int
+usif_notify_del(struct drm_file *f, void *data, u32 size, void *argv, u32 argc)
+{
+	struct nouveau_cli *cli = nouveau_cli(f);
+	struct nvif_client *client = &cli->base;
+	union {
+		struct nvif_ioctl_ntfy_del_v0 v0;
+	} *args = data;
+	struct usif_notify *ntfy;
+	int ret;
+
+	if (nvif_unpack(args->v0, 0, 0, true)) {
+		if (!(ntfy = usif_notify_find(f, args->v0.index)))
+			return -ENOENT;
+	} else
+		return ret;
+
+	ret = nvif_client_ioctl(client, argv, argc);
+	if (ret == 0)
+		usif_notify_dtor(ntfy);
+	return ret;
+}
+
+static int
+usif_notify_get(struct drm_file *f, void *data, u32 size, void *argv, u32 argc)
+{
+	struct nouveau_cli *cli = nouveau_cli(f);
+	struct nvif_client *client = &cli->base;
+	union {
+		struct nvif_ioctl_ntfy_del_v0 v0;
+	} *args = data;
+	struct usif_notify *ntfy;
+	int ret;
+
+	if (nvif_unpack(args->v0, 0, 0, true)) {
+		if (!(ntfy = usif_notify_find(f, args->v0.index)))
+			return -ENOENT;
+	} else
+		return ret;
+
+	if (atomic_xchg(&ntfy->enabled, 1))
+		return 0;
+
+	ntfy->p = kmalloc(sizeof(*ntfy->p) + ntfy->reply, GFP_KERNEL);
+	if (ret = -ENOMEM, !ntfy->p)
+		goto done;
+	ntfy->p->base.event = &ntfy->p->e.base;
+	ntfy->p->base.file_priv = f;
+	ntfy->p->base.pid = current->pid;
+	ntfy->p->base.destroy =(void(*)(struct drm_pending_event *))kfree;
+	ntfy->p->e.base.type = DRM_NOUVEAU_EVENT_NVIF;
+	ntfy->p->e.base.length = sizeof(ntfy->p->e.base) + ntfy->reply;
+
+	ret = nvif_client_ioctl(client, argv, argc);
+done:
+	if (ret) {
+		atomic_set(&ntfy->enabled, 0);
+		kfree(ntfy->p);
+	}
+	return ret;
+}
+
+static int
+usif_notify_put(struct drm_file *f, void *data, u32 size, void *argv, u32 argc)
+{
+	struct nouveau_cli *cli = nouveau_cli(f);
+	struct nvif_client *client = &cli->base;
+	union {
+		struct nvif_ioctl_ntfy_put_v0 v0;
+	} *args = data;
+	struct usif_notify *ntfy;
+	int ret;
+
+	if (nvif_unpack(args->v0, 0, 0, true)) {
+		if (!(ntfy = usif_notify_find(f, args->v0.index)))
+			return -ENOENT;
+	} else
+		return ret;
+
+	ret = nvif_client_ioctl(client, argv, argc);
+	if (ret == 0 && atomic_xchg(&ntfy->enabled, 0))
+		kfree(ntfy->p);
+	return ret;
+}
+
+struct usif_object {
+	struct list_head head;
+	struct list_head ntfy;
+	u8  route;
+	u64 token;
+};
+
+static void
+usif_object_dtor(struct usif_object *object)
+{
+	list_del(&object->head);
+	kfree(object);
+}
+
+static int
+usif_object_new(struct drm_file *f, void *data, u32 size, void *argv, u32 argc)
+{
+	struct nouveau_cli *cli = nouveau_cli(f);
+	struct nvif_client *client = &cli->base;
+	union {
+		struct nvif_ioctl_new_v0 v0;
+	} *args = data;
+	struct usif_object *object;
+	int ret;
+
+	if (!(object = kmalloc(sizeof(*object), GFP_KERNEL)))
+		return -ENOMEM;
+	list_add(&object->head, &cli->objects);
+
+	if (nvif_unpack(args->v0, 0, 0, true)) {
+		object->route = args->v0.route;
+		object->token = args->v0.token;
+		args->v0.route = NVDRM_OBJECT_USIF;
+		args->v0.token = (unsigned long)(void *)object;
+		ret = nvif_client_ioctl(client, argv, argc);
+		args->v0.token = object->token;
+		args->v0.route = object->route;
+	}
+
+	if (ret)
+		usif_object_dtor(object);
+	return ret;
+}
+
+int
+usif_ioctl(struct drm_file *filp, void __user *user, u32 argc)
+{
+	struct nouveau_cli *cli = nouveau_cli(filp);
+	struct nvif_client *client = &cli->base;
+	void *data = kmalloc(argc, GFP_KERNEL);
+	u32   size = argc;
+	union {
+		struct nvif_ioctl_v0 v0;
+	} *argv = data;
+	struct usif_object *object;
+	u8 owner;
+	int ret;
+
+	if (ret = -ENOMEM, !argv)
+		goto done;
+	if (ret = -EFAULT, copy_from_user(argv, user, size))
+		goto done;
+
+	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;
+	} else
+		goto done;
+
+	mutex_lock(&cli->mutex);
+	switch (argv->v0.type) {
+	case NVIF_IOCTL_V0_NEW:
+		/* ... except if we're creating children */
+		argv->v0.owner = NVIF_IOCTL_V0_OWNER_ANY;
+		ret = usif_object_new(filp, data, size, argv, argc);
+		break;
+	case NVIF_IOCTL_V0_NTFY_NEW:
+		ret = usif_notify_new(filp, data, size, argv, argc);
+		break;
+	case NVIF_IOCTL_V0_NTFY_DEL:
+		ret = usif_notify_del(filp, data, size, argv, argc);
+		break;
+	case NVIF_IOCTL_V0_NTFY_GET:
+		ret = usif_notify_get(filp, data, size, argv, argc);
+		break;
+	case NVIF_IOCTL_V0_NTFY_PUT:
+		ret = usif_notify_put(filp, data, size, argv, argc);
+		break;
+	default:
+		ret = nvif_client_ioctl(client, argv, argc);
+		break;
+	}
+	if (argv->v0.route == NVDRM_OBJECT_USIF) {
+		object = (void *)(unsigned long)argv->v0.token;
+		argv->v0.route = object->route;
+		argv->v0.token = object->token;
+		if (ret == 0 && argv->v0.type == NVIF_IOCTL_V0_DEL) {
+			list_del(&object->head);
+			kfree(object);
+		}
+	} else {
+		argv->v0.route = NVIF_IOCTL_V0_ROUTE_HIDDEN;
+		argv->v0.token = 0;
+	}
+	argv->v0.owner = owner;
+	mutex_unlock(&cli->mutex);
+
+	if (copy_to_user(user, argv, argc))
+		ret = -EFAULT;
+done:
+	kfree(argv);
+	return ret;
+}
+
+void
+usif_client_fini(struct nouveau_cli *cli)
+{
+	struct usif_object *object, *otemp;
+	struct usif_notify *notify, *ntemp;
+
+	list_for_each_entry_safe(notify, ntemp, &cli->notifys, head) {
+		usif_notify_dtor(notify);
+	}
+
+	list_for_each_entry_safe(object, otemp, &cli->objects, head) {
+		usif_object_dtor(object);
+	}
+}
+
+void
+usif_client_init(struct nouveau_cli *cli)
+{
+	INIT_LIST_HEAD(&cli->objects);
+	INIT_LIST_HEAD(&cli->notifys);
+}