Re: [PATCH] optee: support wq_sleep_timeout

Jerome Forissier
2024-01-25T09:46:38Z

On 1/25/24 06:27, gavin.liu via OP-TEE wrote:
> From: Gavin Liu <gavin.liu@mediatek.com>
>
> Add wq_sleep_timeout to support self waking when timeout for secure
> driver usage.
>
> Signed-off-by: Gavin Liu <gavin.liu@mediatek.com>
> ---
> drivers/tee/optee/notif.c | 9 +++++++--
> drivers/tee/optee/optee_private.h | 2 +-
> drivers/tee/optee/rpc.c | 10 ++++++++--
> 3 files changed, 16 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/tee/optee/notif.c b/drivers/tee/optee/notif.c
> index 05212842b0a5..d5e5c0645609 100644
> --- a/drivers/tee/optee/notif.c
> +++ b/drivers/tee/optee/notif.c
> @@ -29,7 +29,7 @@ static bool have_key(struct optee *optee, u_int key)
> return false;
> }
>
> -int optee_notif_wait(struct optee *optee, u_int key)
> +int optee_notif_wait(struct optee *optee, u_int key, u32 timeout)
> {
> unsigned long flags;
> struct notif_entry *entry;
> @@ -70,7 +70,12 @@ int optee_notif_wait(struct optee *optee, u_int key)
> * Unlock temporarily and wait for completion.
> */
> spin_unlock_irqrestore(&optee->notif.lock, flags);
> - wait_for_completion(&entry->c);
> + if (timeout != 0) {
> + if (!wait_for_completion_timeout(&entry->c, timeout))
> + rc = -ETIMEDOUT;
> + } else {
> + wait_for_completion(&entry->c);
> + }
> spin_lock_irqsave(&optee->notif.lock, flags);
>
> list_del(&entry->link);
> diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
> index 7a5243c78b55..da990c4016ec 100644
> --- a/drivers/tee/optee/optee_private.h
> +++ b/drivers/tee/optee/optee_private.h
> @@ -252,7 +252,7 @@ struct optee_call_ctx {
>
> int optee_notif_init(struct optee *optee, u_int max_key);
> void optee_notif_uninit(struct optee *optee);
> -int optee_notif_wait(struct optee *optee, u_int key);
> +int optee_notif_wait(struct optee *optee, u_int key, u32 timeout);
> int optee_notif_send(struct optee *optee, u_int key);
>
> u32 optee_supp_thrd_req(struct tee_context *ctx, u32 func, size_t num_params,
> diff --git a/drivers/tee/optee/rpc.c b/drivers/tee/optee/rpc.c
> index e69bc6380683..14e6246aaf05 100644
> --- a/drivers/tee/optee/rpc.c
> +++ b/drivers/tee/optee/rpc.c
> @@ -130,6 +130,8 @@ static void handle_rpc_func_cmd_i2c_transfer(struct tee_context *ctx,
> static void handle_rpc_func_cmd_wq(struct optee *optee,
> struct optee_msg_arg *arg)
> {
> + int rc = 0;
> +
> if (arg->num_params != 1)
> goto bad;
>
> @@ -139,7 +141,8 @@ static void handle_rpc_func_cmd_wq(struct optee *optee,
>
> switch (arg->params[0].u.value.a) {
> case OPTEE_RPC_NOTIFICATION_WAIT:
> - if (optee_notif_wait(optee, arg->params[0].u.value.b))
> + rc = optee_notif_wait(optee, arg->params[0].u.value.b, arg->params[0].u.value.c);

optee/optee_rpc_cmd.h needs updating (near "Waiting on notification") to reflect the meaning
of value.c.

Was value.c required to be zero prior to this change? Otherwise this could lead to undefined
behavior.

> + if (rc)
> goto bad;
> break;
> case OPTEE_RPC_NOTIFICATION_SEND:
> @@ -153,7 +156,10 @@ static void handle_rpc_func_cmd_wq(struct optee *optee,
> arg->ret = TEEC_SUCCESS;
> return;
> bad:
> - arg->ret = TEEC_ERROR_BAD_PARAMETERS;
> + if (rc == -ETIMEDOUT)
> + arg->ret = TEEC_ERROR_BUSY;
> + else
> + arg->ret = TEEC_ERROR_BAD_PARAMETERS;
> }
>
> static void handle_rpc_func_cmd_wait(struct optee_msg_arg *arg)

--
Jerome