2023-12-15 11:52:49

by Peng Fan (OSS)

Subject: [PATCH 1/7] firmware: arm_scmi: introduce helper get_max_msg_size

From: Peng Fan <[email protected]>

When Agent sending data to SCMI server, the Agent driver could check
the size to avoid protocol buffer overflow. So introduce the helper
get_max_msg_size.

Signed-off-by: Peng Fan <[email protected]>
---
drivers/firmware/arm_scmi/driver.c | 15 +++++++++++++++
drivers/firmware/arm_scmi/protocols.h | 1 +
2 files changed, 16 insertions(+)

diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index a9f70e6e58ac..b4f8f190351b 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -1481,6 +1481,20 @@ static int scmi_common_extended_name_get(const struct scmi_protocol_handle *ph,
return ret;
}

+/**
+ * scmi_common_get_max_msg_size - Get maximum message size
+ * @ph: A protocol handle reference.
+ *
+ * Return: Maximum message size for the current protocol.
+ */
+static int scmi_common_get_max_msg_size(const struct scmi_protocol_handle *ph)
+{
+ const struct scmi_protocol_instance *pi = ph_to_pi(ph);
+ struct scmi_info *info = handle_to_scmi_info(pi->handle);
+
+ return info->desc->max_msg_size;
+}
+
/**
* struct scmi_iterator - Iterator descriptor
* @msg: A reference to the message TX buffer; filled by @prepare_message with
@@ -1756,6 +1770,7 @@ static void scmi_common_fastchannel_db_ring(struct scmi_fc_db_info *db)

static const struct scmi_proto_helpers_ops helpers_ops = {
.extended_name_get = scmi_common_extended_name_get,
+ .get_max_msg_size = scmi_common_get_max_msg_size,
.iter_response_init = scmi_iterator_init,
.iter_response_run = scmi_iterator_run,
.fastchannel_init = scmi_common_fastchannel_init,
diff --git a/drivers/firmware/arm_scmi/protocols.h b/drivers/firmware/arm_scmi/protocols.h
index e683c26f24eb..08de8dc064c1 100644
--- a/drivers/firmware/arm_scmi/protocols.h
+++ b/drivers/firmware/arm_scmi/protocols.h
@@ -270,6 +270,7 @@ struct scmi_proto_helpers_ops {
void __iomem **p_addr,
struct scmi_fc_db_info **p_db);
void (*fastchannel_db_ring)(struct scmi_fc_db_info *db);
+ int (*get_max_msg_size)(const struct scmi_protocol_handle *ph);
};

/**

--
2.37.1

2023-12-22 15:30:32

by Cristian Marussi

Subject: Re: [PATCH 1/7] firmware: arm_scmi: introduce helper get_max_msg_size

On Fri, Dec 15, 2023 at 07:56:29PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <[email protected]>
>
> When Agent sending data to SCMI server, the Agent driver could check
> the size to avoid protocol buffer overflow. So introduce the helper
> get_max_msg_size.
>
> Signed-off-by: Peng Fan <[email protected]>
> ---
> drivers/firmware/arm_scmi/driver.c | 15 +++++++++++++++
> drivers/firmware/arm_scmi/protocols.h | 1 +
> 2 files changed, 16 insertions(+)
>
> diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
> index a9f70e6e58ac..b4f8f190351b 100644
> --- a/drivers/firmware/arm_scmi/driver.c
> +++ b/drivers/firmware/arm_scmi/driver.c
> @@ -1481,6 +1481,20 @@ static int scmi_common_extended_name_get(const struct scmi_protocol_handle *ph,
> return ret;
> }
>
> +/**
> + * scmi_common_get_max_msg_size - Get maximum message size
> + * @ph: A protocol handle reference.
> + *
> + * Return: Maximum message size for the current protocol.
> + */
> +static int scmi_common_get_max_msg_size(const struct scmi_protocol_handle *ph)
> +{
> + const struct scmi_protocol_instance *pi = ph_to_pi(ph);
> + struct scmi_info *info = handle_to_scmi_info(pi->handle);
> +
> + return info->desc->max_msg_size;
> +}
> +
> /**
> * struct scmi_iterator - Iterator descriptor
> * @msg: A reference to the message TX buffer; filled by @prepare_message with
> @@ -1756,6 +1770,7 @@ static void scmi_common_fastchannel_db_ring(struct scmi_fc_db_info *db)
>
> static const struct scmi_proto_helpers_ops helpers_ops = {
> .extended_name_get = scmi_common_extended_name_get,
> + .get_max_msg_size = scmi_common_get_max_msg_size,
> .iter_response_init = scmi_iterator_init,
> .iter_response_run = scmi_iterator_run,
> .fastchannel_init = scmi_common_fastchannel_init,
> diff --git a/drivers/firmware/arm_scmi/protocols.h b/drivers/firmware/arm_scmi/protocols.h
> index e683c26f24eb..08de8dc064c1 100644
> --- a/drivers/firmware/arm_scmi/protocols.h
> +++ b/drivers/firmware/arm_scmi/protocols.h
> @@ -270,6 +270,7 @@ struct scmi_proto_helpers_ops {
> void __iomem **p_addr,
> struct scmi_fc_db_info **p_db);
> void (*fastchannel_db_ring)(struct scmi_fc_db_info *db);
> + int (*get_max_msg_size)(const struct scmi_protocol_handle *ph);
> };

This looks good to me, but please add a comment for this new helper in
the comment block above.

Other than that:

Reviewed-by: Cristian Marussi <[email protected]>

Thanks,
Cristian