drm/nouveau/nvif: import library functions for the ioctl/event interfaces

This is a wrapper around the interfaces defined in an earlier commit,
and is also used by various userspace (either by a libdrm backend, or
libpciaccess) tools/tests.

In the future this will be extended to handle channels, replacing some
long-unloved code we currently use, and allow fifo/display/mpeg (hi
Ilia ;)) engines to all be exposed in the same way.

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

1 files changed, 237 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/nvif/notify.c b/drivers/gpu/drm/nouveau/nvif/notify.c
new file mode 100644
index 000000000000..7c06123a559c
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nvif/notify.c
@@ -0,0 +1,237 @@
+/*
+ * 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 <nvif/client.h>
+#include <nvif/driver.h>
+#include <nvif/notify.h>
+#include <nvif/object.h>
+#include <nvif/ioctl.h>
+#include <nvif/event.h>
+
+static inline int
+nvif_notify_put_(struct nvif_notify *notify)
+{
+	struct nvif_object *object = notify->object;
+	struct {
+		struct nvif_ioctl_v0 ioctl;
+		struct nvif_ioctl_ntfy_put_v0 ntfy;
+	} args = {
+		.ioctl.type = NVIF_IOCTL_V0_NTFY_PUT,
+		.ntfy.index = notify->index,
+	};
+
+	if (atomic_inc_return(&notify->putcnt) != 1)
+		return 0;
+
+	return nvif_object_ioctl(object, &args, sizeof(args), NULL);
+}
+
+int
+nvif_notify_put(struct nvif_notify *notify)
+{
+	if (likely(notify->object) &&
+	    test_and_clear_bit(NVIF_NOTIFY_USER, &notify->flags)) {
+		int ret = nvif_notify_put_(notify);
+		if (test_bit(NVIF_NOTIFY_WORK, &notify->flags))
+			flush_work(&notify->work);
+		return ret;
+	}
+	return 0;
+}
+
+static inline int
+nvif_notify_get_(struct nvif_notify *notify)
+{
+	struct nvif_object *object = notify->object;
+	struct {
+		struct nvif_ioctl_v0 ioctl;
+		struct nvif_ioctl_ntfy_get_v0 ntfy;
+	} args = {
+		.ioctl.type = NVIF_IOCTL_V0_NTFY_GET,
+		.ntfy.index = notify->index,
+	};
+
+	if (atomic_dec_return(&notify->putcnt) != 0)
+		return 0;
+
+	return nvif_object_ioctl(object, &args, sizeof(args), NULL);
+}
+
+int
+nvif_notify_get(struct nvif_notify *notify)
+{
+	if (likely(notify->object) &&
+	    !test_and_set_bit(NVIF_NOTIFY_USER, &notify->flags))
+		return nvif_notify_get_(notify);
+	return 0;
+}
+
+static void
+nvif_notify_work(struct work_struct *work)
+{
+	struct nvif_notify *notify = container_of(work, typeof(*notify), work);
+	if (notify->func(notify) == NVIF_NOTIFY_KEEP)
+		nvif_notify_get_(notify);
+}
+
+int
+nvif_notify(const void *header, u32 length, const void *data, u32 size)
+{
+	struct nvif_notify *notify = NULL;
+	const union {
+		struct nvif_notify_rep_v0 v0;
+	} *args = header;
+	int ret = NVIF_NOTIFY_DROP;
+
+	if (length == sizeof(args->v0) && args->v0.version == 0) {
+		if (WARN_ON(args->v0.route))
+			return NVIF_NOTIFY_DROP;
+		notify = (void *)(unsigned long)args->v0.token;
+	}
+
+	if (!WARN_ON(notify == NULL)) {
+		struct nvif_client *client = nvif_client(notify->object);
+		if (!WARN_ON(notify->size != size)) {
+			if (test_bit(NVIF_NOTIFY_WORK, &notify->flags)) {
+				atomic_inc(&notify->putcnt);
+				memcpy((void *)notify->data, data, size);
+				schedule_work(&notify->work);
+				return NVIF_NOTIFY_DROP;
+			}
+			notify->data = data;
+			ret = notify->func(notify);
+			notify->data = NULL;
+			if (ret != NVIF_NOTIFY_DROP && client->driver->keep) {
+				atomic_inc(&notify->putcnt);
+				nvif_notify_get_(notify);
+			}
+		}
+	}
+
+	return ret;
+}
+
+int
+nvif_notify_fini(struct nvif_notify *notify)
+{
+	struct nvif_object *object = notify->object;
+	struct {
+		struct nvif_ioctl_v0 ioctl;
+		struct nvif_ioctl_ntfy_del_v0 ntfy;
+	} args = {
+		.ioctl.type = NVIF_IOCTL_V0_NTFY_DEL,
+		.ntfy.index = notify->index,
+	};
+	int ret = nvif_notify_put(notify);
+	if (ret >= 0 && object) {
+		ret = nvif_object_ioctl(object, &args, sizeof(args), NULL);
+		if (ret == 0) {
+			nvif_object_ref(NULL, &notify->object);
+			kfree((void *)notify->data);
+		}
+	}
+	return ret;
+}
+
+int
+nvif_notify_init(struct nvif_object *object, void (*dtor)(struct nvif_notify *),
+		 int (*func)(struct nvif_notify *), bool work, u8 event,
+		 void *data, u32 size, u32 reply, struct nvif_notify *notify)
+{
+	struct {
+		struct nvif_ioctl_v0 ioctl;
+		struct nvif_ioctl_ntfy_new_v0 ntfy;
+		struct nvif_notify_req_v0 req;
+	} *args;
+	int ret = -ENOMEM;
+
+	notify->object = NULL;
+	nvif_object_ref(object, &notify->object);
+	notify->flags = 0;
+	atomic_set(&notify->putcnt, 1);
+	notify->dtor = dtor;
+	notify->func = func;
+	notify->data = NULL;
+	notify->size = reply;
+	if (work) {
+		INIT_WORK(&notify->work, nvif_notify_work);
+		set_bit(NVIF_NOTIFY_WORK, &notify->flags);
+		notify->data = kmalloc(notify->size, GFP_KERNEL);
+		if (!notify->data)
+			goto done;
+	}
+
+	if (!(args = kmalloc(sizeof(*args) + size, GFP_KERNEL)))
+		goto done;
+	args->ioctl.version = 0;
+	args->ioctl.type = NVIF_IOCTL_V0_NTFY_NEW;
+	args->ntfy.version = 0;
+	args->ntfy.event = event;
+	args->req.version = 0;
+	args->req.reply = notify->size;
+	args->req.route = 0;
+	args->req.token = (unsigned long)(void *)notify;
+
+	memcpy(args->req.data, data, size);
+	ret = nvif_object_ioctl(object, args, sizeof(*args) + size, NULL);
+	notify->index = args->ntfy.index;
+	kfree(args);
+done:
+	if (ret)
+		nvif_notify_fini(notify);
+	return ret;
+}
+
+static void
+nvif_notify_del(struct nvif_notify *notify)
+{
+	nvif_notify_fini(notify);
+	kfree(notify);
+}
+
+void
+nvif_notify_ref(struct nvif_notify *notify, struct nvif_notify **pnotify)
+{
+	BUG_ON(notify != NULL);
+	if (*pnotify)
+		(*pnotify)->dtor(*pnotify);
+	*pnotify = notify;
+}
+
+int
+nvif_notify_new(struct nvif_object *object, int (*func)(struct nvif_notify *),
+		bool work, u8 type, void *data, u32 size, u32 reply,
+		struct nvif_notify **pnotify)
+{
+	struct nvif_notify *notify = kzalloc(sizeof(*notify), GFP_KERNEL);
+	if (notify) {
+		int ret = nvif_notify_init(object, nvif_notify_del, func, work,
+					   type, data, size, reply, notify);
+		if (ret)
+			kfree(notify);
+		*pnotify = notify;
+		return ret;
+	}
+	return -ENOMEM;
+}