ioat/dca: Use struct_size() helper

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 ioat_dca_priv {
	...
        struct ioat_dca_slot     req_slots[0];
};

Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes.

So, replace the following form:

sizeof(*ioatdca) + (sizeof(struct ioat_dca_slot) * slots)

with:

struct_size(ioatdca, req_slots, slots)

This code was detected with the help of Coccinelle.

Signed-off-by Gustavo A. R. Silva <[email protected]>

---
 drivers/dma/ioat/dca.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

drivers/dma/ioat/dca.c +1 -2

index 70fd8454d002..be61c32a876f 100644
@@ -286,8 +286,7 @@ struct dca_provider *ioat_dca_init(struct pci_dev *pdev, void __iomem *iobase)
 		return NULL;
 
 	dca = alloc_dca_provider(&ioat_dca_ops,
-				 sizeof(*ioatdca)
-				      + (sizeof(struct ioat_dca_slot) * slots));
+				 struct_size(ioatdca, req_slots, slots));
 	if (!dca)
 		return NULL;
 

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 ioat_dca_priv {
	...
        struct ioat_dca_slot     req_slots[0];
};

Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes.

So, replace the following form:

sizeof(*ioatdca) + (sizeof(struct ioat_dca_slot) * slots)

with:

struct_size(ioatdca, req_slots, slots)

This code was detected with the help of Coccinelle.