nfp: flower: cmsg: use struct_size() helper
authorGustavo A. R. Silva <gustavo@embeddedor.com>
Fri, 8 Feb 2019 03:47:25 +0000 (21:47 -0600)
committerDavid S. Miller <davem@davemloft.net>
Sat, 9 Feb 2019 06:57:28 +0000 (22:57 -0800)
commitaf6f12f22b141d755876ab95635619166b1c574e
tree3b365fef952e149500381132781c6be5c6068d6a
parent9e475293cd40fc9c14de63c53b5754f06007059d
nfp: flower: cmsg: 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 foo {
    int stuff;
    void *entry[];
};

size = sizeof(struct foo) + count * sizeof(void *);
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: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/netronome/nfp/flower/cmsg.c