This flag indicates that requests in this context should not wait for tee-supplicant daemon to be started if not present and just return with an error code. It is needed for requests which should be non-blocking in nature like ones arising from TEE based kernel drivers or any in kernel api that uses TEE internal client interface.
Signed-off-by: Sumit Garg sumit.garg@linaro.org --- drivers/tee/optee/supp.c | 10 +++++++++- drivers/tee/tee_core.c | 13 +++++++++++++ include/linux/tee_drv.h | 6 ++++++ 3 files changed, 28 insertions(+), 1 deletion(-)
diff --git a/drivers/tee/optee/supp.c b/drivers/tee/optee/supp.c index 43626e1..92f56b8 100644 --- a/drivers/tee/optee/supp.c +++ b/drivers/tee/optee/supp.c @@ -88,10 +88,18 @@ u32 optee_supp_thrd_req(struct tee_context *ctx, u32 func, size_t num_params, { struct optee *optee = tee_get_drvdata(ctx->teedev); struct optee_supp *supp = &optee->supp; - struct optee_supp_req *req = kzalloc(sizeof(*req), GFP_KERNEL); + struct optee_supp_req *req; bool interruptable; u32 ret;
+ /* + * Return in case there is no supplicant available and + * non-blocking request. + */ + if (!supp->ctx && ctx->supp_nowait) + return TEEC_ERROR_COMMUNICATION; + + req = kzalloc(sizeof(*req), GFP_KERNEL); if (!req) return TEEC_ERROR_OUT_OF_MEMORY;
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 9f4c8bc..2612dfa 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -105,6 +105,11 @@ static int tee_open(struct inode *inode, struct file *filp) if (IS_ERR(ctx)) return PTR_ERR(ctx);
+ /* + * Default user-space behaviour is to wait for tee-supplicant + * if not present for any requests in this context. + */ + ctx->supp_nowait = false; filp->private_data = ctx; return 0; } @@ -981,6 +986,14 @@ tee_client_open_context(struct tee_context *start, } while (IS_ERR(ctx) && PTR_ERR(ctx) != -ENOMEM);
put_device(put_dev); + /* + * Default behaviour for in kernel client is to not wait for + * tee-supplicant if not present for any requests in this context. + * Also this flag could be configured again before call to + * tee_client_open_session() if any in kernel client requires + * different behaviour. + */ + ctx->supp_nowait = true; return ctx; } EXPORT_SYMBOL_GPL(tee_client_open_context); diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h index ce957ce..56d7f1b 100644 --- a/include/linux/tee_drv.h +++ b/include/linux/tee_drv.h @@ -50,6 +50,11 @@ struct tee_shm_pool; * @releasing: flag that indicates if context is being released right now. * It is needed to break circular dependency on context during * shared memory release. + * @supp_nowait: flag that indicates that requests in this context should not + * wait for tee-supplicant daemon to be started if not present + * and just return with an error code. It is needed for requests + * that arises from TEE based kernel drivers that should be + * non-blocking in nature. */ struct tee_context { struct tee_device *teedev; @@ -57,6 +62,7 @@ struct tee_context { void *data; struct kref refcount; bool releasing; + bool supp_nowait; };
struct tee_param_memref {