[PATCH 1/1] tee: add cancellation support to client interface

[Igor Opaniuk]

Add support of cancellation request to the TEE kernel internal
client interface. Can be used by software TPM drivers, that leverage
TEE under the hood (for instance in TPM2.0 mobile profile), for requesting
cancellation of time-consuming operations (RSA key-pair generation etc.).

Signed-off-by: Igor Opaniuk <igor.opaniuk@xxxxxxxxxx>
---
 drivers/tee/tee_core.c  | 12 ++++++++++++
 include/linux/tee_drv.h | 14 ++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c
index 7b2bb4c..aba71a8 100644
--- a/drivers/tee/tee_core.c
+++ b/drivers/tee/tee_core.c
@@ -1027,6 +1027,18 @@ int tee_client_invoke_func(struct tee_context *ctx,
 }
 EXPORT_SYMBOL_GPL(tee_client_invoke_func);
 
+int tee_client_cancel_req(struct tee_context *ctx,
+			  u32 cancel_id,
+			  u32 session)
+{
+
+	if (!ctx->teedev->desc->ops->cancel_req)
+		return -EINVAL;
+	return ctx->teedev->desc->ops->cancel_req(ctx, cancel_id,
+						  session);
+}
+EXPORT_SYMBOL_GPL(tee_client_cancel_req);
+
 static int __init tee_init(void)
 {
 	int rc;
diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h
index 6cfe058..62a0b56 100644
--- a/include/linux/tee_drv.h
+++ b/include/linux/tee_drv.h
@@ -526,6 +526,20 @@ int tee_client_invoke_func(struct tee_context *ctx,
 			   struct tee_ioctl_invoke_arg *arg,
 			   struct tee_param *param);
 
+/**
+ * tee_client_cancel_req() - Request cancellation of the previous open-session
+ * or invoke-command operations in a Trusted Application
+ * @ctx:       TEE Context
+ * @arg:       Unique cancel request id
+ * @param:     Session id
+ *
+ * Returns < 0 on error else see @arg->ret for result.
+ */
+int tee_client_cancel_req(struct tee_context *ctx,
+			  u32 cancel_id,
+			  u32 session);
+
+
 static inline bool tee_param_is_memref(struct tee_param *param)
 {
 	switch (param->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
-- 
2.7.4