On Sat, 7 Sep 2024 15:51:07 +0200
Christophe JAILLET <christophe.jaillet@xxxxxxxxxx> wrote:
> 'struct iio_chan_spec' are not modified in these drivers.
>
> Constifying this structure moves some data to a read-only section, so
> increase overall security.
>
> On a x86_64, with allmodconfig:
> Before:
> ======
> text data bss dec hex filename
> 35749 5879 384 42012 a41c drivers/iio/addac/ad74115.o
> 32242 3297 384 35923 8c53 drivers/iio/addac/ad74413r.o
>
> After:
> =====
> text data bss dec hex filename
> 39109 2519 384 42012 a41c drivers/iio/addac/ad74115.o
> 33842 1697 384 35923 8c53 drivers/iio/addac/ad74413r.o
>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Looks obviously correct. Hopefully looks are not being deceiving.
Applied. Note this is probably next cycle material now given timing.
Jonathan
> ---
> Compile tested only
> ---
> drivers/iio/addac/ad74115.c | 18 +++++++++---------
> drivers/iio/addac/ad74413r.c | 21 +++++++++++----------
> 2 files changed, 20 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/iio/addac/ad74115.c b/drivers/iio/addac/ad74115.c
> index 12dc43d487b4..bdbdd67536ff 100644
> --- a/drivers/iio/addac/ad74115.c
> +++ b/drivers/iio/addac/ad74115.c
> @@ -191,7 +191,7 @@ enum ad74115_gpio_mode {
> };
>
> struct ad74115_channels {
> - struct iio_chan_spec *channels;
> + const struct iio_chan_spec *channels;
> unsigned int num_channels;
> };
>
> @@ -1295,46 +1295,46 @@ static const struct iio_info ad74115_info = {
> _AD74115_ADC_CHANNEL(_type, index, BIT(IIO_CHAN_INFO_SCALE) \
> | BIT(IIO_CHAN_INFO_OFFSET))
>
> -static struct iio_chan_spec ad74115_voltage_input_channels[] = {
> +static const struct iio_chan_spec ad74115_voltage_input_channels[] = {
> AD74115_ADC_CHANNEL(IIO_VOLTAGE, AD74115_ADC_CH_CONV1),
> AD74115_ADC_CHANNEL(IIO_VOLTAGE, AD74115_ADC_CH_CONV2),
> };
>
> -static struct iio_chan_spec ad74115_voltage_output_channels[] = {
> +static const struct iio_chan_spec ad74115_voltage_output_channels[] = {
> AD74115_DAC_CHANNEL(IIO_VOLTAGE, AD74115_DAC_CH_MAIN),
> AD74115_ADC_CHANNEL(IIO_CURRENT, AD74115_ADC_CH_CONV1),
> AD74115_ADC_CHANNEL(IIO_VOLTAGE, AD74115_ADC_CH_CONV2),
> };
>
> -static struct iio_chan_spec ad74115_current_input_channels[] = {
> +static const struct iio_chan_spec ad74115_current_input_channels[] = {
> AD74115_ADC_CHANNEL(IIO_CURRENT, AD74115_ADC_CH_CONV1),
> AD74115_ADC_CHANNEL(IIO_VOLTAGE, AD74115_ADC_CH_CONV2),
> };
>
> -static struct iio_chan_spec ad74115_current_output_channels[] = {
> +static const struct iio_chan_spec ad74115_current_output_channels[] = {
> AD74115_DAC_CHANNEL(IIO_CURRENT, AD74115_DAC_CH_MAIN),
> AD74115_ADC_CHANNEL(IIO_VOLTAGE, AD74115_ADC_CH_CONV1),
> AD74115_ADC_CHANNEL(IIO_VOLTAGE, AD74115_ADC_CH_CONV2),
> };
>
> -static struct iio_chan_spec ad74115_2_wire_resistance_input_channels[] = {
> +static const struct iio_chan_spec ad74115_2_wire_resistance_input_channels[] = {
> _AD74115_ADC_CHANNEL(IIO_RESISTANCE, AD74115_ADC_CH_CONV1,
> BIT(IIO_CHAN_INFO_PROCESSED)),
> AD74115_ADC_CHANNEL(IIO_VOLTAGE, AD74115_ADC_CH_CONV2),
> };
>
> -static struct iio_chan_spec ad74115_3_4_wire_resistance_input_channels[] = {
> +static const struct iio_chan_spec ad74115_3_4_wire_resistance_input_channels[] = {
> AD74115_ADC_CHANNEL(IIO_RESISTANCE, AD74115_ADC_CH_CONV1),
> AD74115_ADC_CHANNEL(IIO_VOLTAGE, AD74115_ADC_CH_CONV2),
> };
>
> -static struct iio_chan_spec ad74115_digital_input_logic_channels[] = {
> +static const struct iio_chan_spec ad74115_digital_input_logic_channels[] = {
> AD74115_DAC_CHANNEL(IIO_VOLTAGE, AD74115_DAC_CH_COMPARATOR),
> AD74115_ADC_CHANNEL(IIO_VOLTAGE, AD74115_ADC_CH_CONV1),
> AD74115_ADC_CHANNEL(IIO_VOLTAGE, AD74115_ADC_CH_CONV2),
> };
>
> -static struct iio_chan_spec ad74115_digital_input_loop_channels[] = {
> +static const struct iio_chan_spec ad74115_digital_input_loop_channels[] = {
> AD74115_DAC_CHANNEL(IIO_CURRENT, AD74115_DAC_CH_MAIN),
> AD74115_DAC_CHANNEL(IIO_VOLTAGE, AD74115_DAC_CH_COMPARATOR),
> AD74115_ADC_CHANNEL(IIO_VOLTAGE, AD74115_ADC_CH_CONV1),
> diff --git a/drivers/iio/addac/ad74413r.c b/drivers/iio/addac/ad74413r.c
> index 2410d72da49b..1e2f6d9804e3 100644
> --- a/drivers/iio/addac/ad74413r.c
> +++ b/drivers/iio/addac/ad74413r.c
> @@ -45,8 +45,8 @@ struct ad74413r_channel_config {
> };
>
> struct ad74413r_channels {
> - struct iio_chan_spec *channels;
> - unsigned int num_channels;
> + const struct iio_chan_spec *channels;
> + unsigned int num_channels;
> };
>
> struct ad74413r_state {
> @@ -1138,34 +1138,34 @@ static const struct iio_info ad74413r_info = {
> AD74413R_ADC_CHANNEL(IIO_CURRENT, BIT(IIO_CHAN_INFO_SCALE) \
> | BIT(IIO_CHAN_INFO_OFFSET))
>
> -static struct iio_chan_spec ad74413r_voltage_output_channels[] = {
> +static const struct iio_chan_spec ad74413r_voltage_output_channels[] = {
> AD74413R_DAC_CHANNEL(IIO_VOLTAGE, BIT(IIO_CHAN_INFO_SCALE)),
> AD74413R_ADC_CURRENT_CHANNEL,
> };
>
> -static struct iio_chan_spec ad74413r_current_output_channels[] = {
> +static const struct iio_chan_spec ad74413r_current_output_channels[] = {
> AD74413R_DAC_CHANNEL(IIO_CURRENT, BIT(IIO_CHAN_INFO_SCALE)),
> AD74413R_ADC_VOLTAGE_CHANNEL,
> };
>
> -static struct iio_chan_spec ad74413r_voltage_input_channels[] = {
> +static const struct iio_chan_spec ad74413r_voltage_input_channels[] = {
> AD74413R_ADC_VOLTAGE_CHANNEL,
> };
>
> -static struct iio_chan_spec ad74413r_current_input_channels[] = {
> +static const struct iio_chan_spec ad74413r_current_input_channels[] = {
> AD74413R_ADC_CURRENT_CHANNEL,
> };
>
> -static struct iio_chan_spec ad74413r_current_input_loop_channels[] = {
> +static const struct iio_chan_spec ad74413r_current_input_loop_channels[] = {
> AD74413R_DAC_CHANNEL(IIO_CURRENT, BIT(IIO_CHAN_INFO_SCALE)),
> AD74413R_ADC_CURRENT_CHANNEL,
> };
>
> -static struct iio_chan_spec ad74413r_resistance_input_channels[] = {
> +static const struct iio_chan_spec ad74413r_resistance_input_channels[] = {
> AD74413R_ADC_CHANNEL(IIO_RESISTANCE, BIT(IIO_CHAN_INFO_PROCESSED)),
> };
>
> -static struct iio_chan_spec ad74413r_digital_input_channels[] = {
> +static const struct iio_chan_spec ad74413r_digital_input_channels[] = {
> AD74413R_ADC_VOLTAGE_CHANNEL,
> };
>
> @@ -1270,7 +1270,8 @@ static int ad74413r_setup_channels(struct iio_dev *indio_dev)
> {
> struct ad74413r_state *st = iio_priv(indio_dev);
> struct ad74413r_channel_config *config;
> - struct iio_chan_spec *channels, *chans;
> + const struct iio_chan_spec *chans;
> + struct iio_chan_spec *channels;
> unsigned int i, num_chans, chan_i;
> int ret;
>
