Re: [PATCH v2 1/4] devres: Provide krealloc_array

Jonathan Cameron
2023-03-11T19:02:13Z

On Thu, 9 Mar 2023 15:03:30 +0000
James Clark <james.clark@arm.com> wrote:

> There is no krealloc_array equivalent in devres. Users would have to
> do their own multiplication overflow check so provide one.
>
> Signed-off-by: James Clark <james.clark@arm.com>

Trivial comment inline, but otherwise seems reasonable to me.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
> Documentation/driver-api/driver-model/devres.rst | 1 +
> include/linux/device.h | 10 ++++++++++
> 2 files changed, 11 insertions(+)
>
> diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
> index 4249eb4239e0..8be086b3f829 100644
> --- a/Documentation/driver-api/driver-model/devres.rst
> +++ b/Documentation/driver-api/driver-model/devres.rst
> @@ -364,6 +364,7 @@ MEM
> devm_kmalloc_array()
> devm_kmemdup()
> devm_krealloc()
> + devm_krealloc_array()
> devm_kstrdup()
> devm_kstrdup_const()
> devm_kvasprintf()
> diff --git a/include/linux/device.h b/include/linux/device.h
> index 1508e637bb26..0dd5956c8516 100644
> --- a/include/linux/device.h
> +++ b/include/linux/device.h
> @@ -223,6 +223,16 @@ static inline void *devm_kcalloc(struct device *dev,
> {
> return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
> }
> +static inline __realloc_size(3, 4) void * __must_check
> +devm_krealloc_array(struct device *dev, void *p, size_t new_n, size_t new_size, gfp_t flags)
> +{
> + size_t bytes;
> +
> + if (unlikely(check_mul_overflow(new_n, new_size, &bytes)))
> + return NULL;

For consistency with krealloc_array and other stuff in device.h that is
of similar 'shape' add a blank line here.

> + return devm_krealloc(dev, p, bytes, flags);
> +}
> +
> void devm_kfree(struct device *dev, const void *p);
> char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp) __malloc;
> const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp);