One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:
struct foo {
int stuff;
struct boo entry[];
};
size = sizeof(struct foo) + count * sizeof(struct boo);
instance = alloc(size, GFP_KERNEL)
Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:
instance = alloc(struct_size(instance, entry, count), GFP_KERNEL)
Notice that, in this case, variable size is not necessary, hence it is
removed.
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
struct regulator_config config;
bool bcores_merged, bmem_bio_merged;
int id, irq, n, n_regulators, ret, val;
- size_t size;
regl_pdata = da9063_pdata ? da9063_pdata->regulators_pdata : NULL;
n_regulators--; /* remove BMEM_BIO_MERGED */
/* Allocate memory required by usable regulators */
- size = sizeof(struct da9063_regulators) +
- n_regulators * sizeof(struct da9063_regulator);
- regulators = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
+ regulators = devm_kzalloc(&pdev->dev, struct_size(regulators,
+ regulator, n_regulators), GFP_KERNEL);
if (!regulators)
return -ENOMEM;