Unverified Commit 97b047e7 authored Feb 22, 2019 by Gustavo A. R. Silva Committed by Mark Brown Feb 26, 2019

regulator: da9062: Use struct_size() in devm_kzalloc()



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>
Acked-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

parent 1ec9c179

drivers/regulator/da9062-regulator.c

+2 −4

Original line number	Diff line number	Diff line
		@@ -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;

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