Re: [PATCH 3/4] iio: adc: Use devm_krealloc_array

[Michal Simek <michal.simek@xxxxxxx>]

On 3/6/23 16:27, James Clark wrote:
> Now that it exists, use it instead of doing the multiplication and
> checking for overflow manually.
>
> Signed-off-by: James Clark <james.clark@xxxxxxx>
> ---
>   drivers/iio/adc/xilinx-ams.c       |  9 +++------
>   drivers/iio/adc/xilinx-xadc-core.c | 17 +++++++----------
>   2 files changed, 10 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/iio/adc/xilinx-ams.c b/drivers/iio/adc/xilinx-ams.c
> index 34cf336b3490..f0b71a1220e0 100644
> --- a/drivers/iio/adc/xilinx-ams.c
> +++ b/drivers/iio/adc/xilinx-ams.c
> @@ -1263,7 +1263,7 @@ static int ams_parse_firmware(struct iio_dev *indio_dev)
>          struct device *dev = indio_dev->dev.parent;
>          struct fwnode_handle *child = NULL;
>          struct fwnode_handle *fwnode = dev_fwnode(dev);
> -       size_t ams_size, dev_size;
> +       size_t ams_size;
>          int ret, ch_cnt = 0, i, rising_off, falling_off;
>          unsigned int num_channels = 0;
>
> @@ -1320,11 +1320,8 @@ static int ams_parse_firmware(struct iio_dev *indio_dev)
>                  }
>          }
>
> -       dev_size = array_size(sizeof(*dev_channels), num_channels);
> -       if (dev_size == SIZE_MAX)
> -               return -ENOMEM;
> -
> -       dev_channels = devm_krealloc(dev, ams_channels, dev_size, GFP_KERNEL);
> +       dev_channels = devm_krealloc_array(dev, ams_channels, num_channels,
> +                                          sizeof(*dev_channels), GFP_KERNEL);
>          if (!dev_channels)
>                  return -ENOMEM;
>
> diff --git a/drivers/iio/adc/xilinx-xadc-core.c b/drivers/iio/adc/xilinx-xadc-core.c
> index 292f2892d223..287df3bb951e 100644
> --- a/drivers/iio/adc/xilinx-xadc-core.c
> +++ b/drivers/iio/adc/xilinx-xadc-core.c
> @@ -613,20 +613,17 @@ static int xadc_update_scan_mode(struct iio_dev *indio_dev,
>          const unsigned long *mask)
>   {
>          struct xadc *xadc = iio_priv(indio_dev);
> -       size_t new_size, n;
> +       size_t n;
>          void *data;
>
>          n = bitmap_weight(mask, indio_dev->masklength);
>
> -       if (check_mul_overflow(n, sizeof(*xadc->data), &new_size))
> -               return -ENOMEM;
> -
> -       data = devm_krealloc(indio_dev->dev.parent, xadc->data,
> -                            new_size, GFP_KERNEL);
> +       data = devm_krealloc_array(indio_dev->dev.parent, xadc->data,
> +                                  n, sizeof(*xadc->data), GFP_KERNEL);
>          if (!data)
>                  return -ENOMEM;
>
> -       memset(data, 0, new_size);
> +       memset(data, 0, n*sizeof(*xadc->data));

this is not correct coding style.

M