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 <gust...@embeddedor.com>
---
drivers/regulator/da9062-regulator.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/drivers/regulator/da9062-regulator.c
b/drivers/regulator/da9062-regulator.c
index 4c5d6ad853f8..b064d8a19d4c 100644
--- a/drivers/regulator/da9062-regulator.c
+++ b/drivers/regulator/da9062-regulator.c
@@ -992,7 +992,6 @@ static int da9062_regulator_probe(struct platform_device
*pdev)
struct regulator_config config = { };
const struct da9062_regulator_info *rinfo;
int irq, n, ret;
- size_t size;
int max_regulators;
switch (chip->chip_type) {
@@ -1010,9 +1009,8 @@ static int da9062_regulator_probe(struct platform_device
*pdev)
}
/* Allocate memory required by usable regulators */
- size = sizeof(struct da9062_regulators) +
- max_regulators * sizeof(struct da9062_regulator);
- regulators = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
+ regulators = devm_kzalloc(&pdev->dev, struct_size(regulators, regulator,
+ max_regulators), GFP_KERNEL);
if (!regulators)
return -ENOMEM;
--
2.20.1
