tee: add kernel internal client interface **not for mainline**

Adds a kernel internal TEE client interface to be used by other drivers.

Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
From: https://github.com/linaro-swg/linux.git
(cherry picked from commit 860c46087c99c24073cc722b12c0017bb0ce0a79)

drivers/tee/tee_core.c

@@ -38,15 +38,13 @@ static DEFINE_SPINLOCK(driver_lock);
 static struct class *tee_class;
 static dev_t tee_devt;
 
-static int tee_open(struct inode *inode, struct file *filp)
+static struct tee_context *teedev_open(struct tee_device *teedev)
 {
 	int rc;
-	struct tee_device *teedev;
 	struct tee_context *ctx;
 
-	teedev = container_of(inode->i_cdev, struct tee_device, cdev);
 	if (!tee_device_get(teedev))
-		return -EINVAL;
+		return ERR_PTR(-EINVAL);
 
 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
 	if (!ctx) {
@@ -56,22 +54,20 @@ static int tee_open(struct inode *inode, struct file *filp)
 
 	ctx->teedev = teedev;
 	INIT_LIST_HEAD(&ctx->list_shm);
-	filp->private_data = ctx;
 	rc = teedev->desc->ops->open(ctx);
 	if (rc)
 		goto err;
 
-	return 0;
+	return ctx;
 err:
 	kfree(ctx);
 	tee_device_put(teedev);
-	return rc;
+	return ERR_PTR(rc);
+
 }
 
-static int tee_release(struct inode *inode, struct file *filp)
+static void teedev_close_context(struct tee_context *ctx)
 {
-	struct tee_context *ctx = filp->private_data;
-	struct tee_device *teedev = ctx->teedev;
 	struct tee_shm *shm;
 
 	ctx->teedev->desc->ops->release(ctx);
@@ -79,8 +75,25 @@ static int tee_release(struct inode *inode, struct file *filp)
 	list_for_each_entry(shm, &ctx->list_shm, link)
 		shm->ctx = NULL;
 	mutex_unlock(&ctx->teedev->mutex);
+	tee_device_put(ctx->teedev);
 	kfree(ctx);
-	tee_device_put(teedev);
+}
+
+static int tee_open(struct inode *inode, struct file *filp)
+{
+	struct tee_context *ctx;
+
+	ctx = teedev_open(container_of(inode->i_cdev, struct tee_device, cdev));
+	if (IS_ERR(ctx))
+		return PTR_ERR(ctx);
+
+	filp->private_data = ctx;
+	return 0;
+}
+
+static int tee_release(struct inode *inode, struct file *filp)
+{
+	teedev_close_context(filp->private_data);
 	return 0;
 }
 
@@ -911,6 +924,96 @@ void *tee_get_drvdata(struct tee_device *teedev)
 }
 EXPORT_SYMBOL_GPL(tee_get_drvdata);
 
+struct match_dev_data {
+	struct tee_ioctl_version_data *vers;
+	const void *data;
+	int (*match)(struct tee_ioctl_version_data *, const void *);
+};
+
+static int match_dev(struct device *dev, const void *data)
+{
+	const struct match_dev_data *match_data = data;
+	struct tee_device *teedev = container_of(dev, struct tee_device, dev);
+
+	teedev->desc->ops->get_version(teedev, match_data->vers);
+	return match_data->match(match_data->vers, match_data->data);
+}
+
+struct tee_context *tee_client_open_context(struct tee_context *start,
+			int (*match)(struct tee_ioctl_version_data *,
+				const void *),
+			const void *data, struct tee_ioctl_version_data *vers)
+{
+	struct device *dev = NULL;
+	struct device *put_dev = NULL;
+	struct tee_context *ctx = NULL;
+	struct tee_ioctl_version_data v;
+	struct match_dev_data match_data = { vers ? vers : &v, data, match };
+
+	if (start)
+		dev = &start->teedev->dev;
+
+	do {
+		dev = class_find_device(tee_class, dev, &match_data, match_dev);
+		if (!dev) {
+			ctx = ERR_PTR(-ENOENT);
+			break;
+		}
+
+		put_device(put_dev);
+		put_dev = dev;
+
+		ctx = teedev_open(container_of(dev, struct tee_device, dev));
+	} while (IS_ERR(ctx) && PTR_ERR(ctx) != -ENOMEM);
+
+	put_device(put_dev);
+	return ctx;
+}
+EXPORT_SYMBOL_GPL(tee_client_open_context);
+
+void tee_client_close_context(struct tee_context *ctx)
+{
+	teedev_close_context(ctx);
+}
+
+EXPORT_SYMBOL_GPL(tee_client_close_context);
+
+void tee_client_get_version(struct tee_context *ctx,
+			struct tee_ioctl_version_data *vers)
+{
+	ctx->teedev->desc->ops->get_version(ctx->teedev, vers);
+}
+EXPORT_SYMBOL_GPL(tee_client_get_version);
+
+
+int tee_client_open_session(struct tee_context *ctx,
+			struct tee_ioctl_open_session_arg *arg,
+			struct tee_param *param)
+{
+	if (!ctx->teedev->desc->ops->open_session)
+		return -EINVAL;
+	return ctx->teedev->desc->ops->open_session(ctx, arg, param);
+}
+EXPORT_SYMBOL_GPL(tee_client_open_session);
+
+int tee_client_close_session(struct tee_context *ctx, u32 session)
+{
+	if (!ctx->teedev->desc->ops->close_session)
+		return -EINVAL;
+	return ctx->teedev->desc->ops->close_session(ctx, session);
+}
+EXPORT_SYMBOL_GPL(tee_client_close_session);
+
+int tee_client_invoke_func(struct tee_context *ctx,
+			struct tee_ioctl_invoke_arg *arg,
+			struct tee_param *param)
+{
+	if (!ctx->teedev->desc->ops->invoke_func)
+		return -EINVAL;
+	return ctx->teedev->desc->ops->invoke_func(ctx, arg, param);
+}
+EXPORT_SYMBOL_GPL(tee_client_invoke_func);
+
 static int __init tee_init(void)
 {
 	int rc;

include/linux/tee_drv.h

@@ -286,4 +286,24 @@ int tee_shm_get_id(struct tee_shm *shm);
  */
 struct tee_shm *tee_shm_get_from_id(struct tee_context *ctx, int id);
 
+struct tee_context *tee_client_open_context(struct tee_context *start,
+			int (*match)(struct tee_ioctl_version_data *,
+				const void *),
+			const void *data, struct tee_ioctl_version_data *vers);
+
+void tee_client_close_context(struct tee_context *ctx);
+
+void tee_client_get_version(struct tee_context *ctx,
+			struct tee_ioctl_version_data *vers);
+
+int tee_client_open_session(struct tee_context *ctx,
+			struct tee_ioctl_open_session_arg *arg,
+			struct tee_param *param);
+
+int tee_client_close_session(struct tee_context *ctx, u32 session);
+
+int tee_client_invoke_func(struct tee_context *ctx,
+			struct tee_ioctl_invoke_arg *arg,
+			struct tee_param *param);
+
 #endif /*__TEE_DRV_H*/