ice: 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;
    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:

size = struct_size(instance, entry, count);

This code was detected with the help of Coccinelle.

Signed-off-by: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --git a/drivers/net/ethernet/intel/ice/ice_sched.c b/drivers/net/ethernet/intel/ice/ice_sched.c
index 8d49f83..2a23250 100644 (file)
--- a/drivers/net/ethernet/intel/ice/ice_sched.c
+++ b/drivers/net/ethernet/intel/ice/ice_sched.c
@@ -683,10 +683,10 @@ ice_sched_add_elems(struct ice_port_info *pi, struct ice_sched_node *tc_node,
        u16 i, num_groups_added = 0;
        enum ice_status status = 0;
        struct ice_hw *hw = pi->hw;
-       u16 buf_size;
+       size_t buf_size;
        u32 teid;
 
-       buf_size = sizeof(*buf) + sizeof(*buf->generic) * (num_nodes - 1);
+       buf_size = struct_size(buf, generic, num_nodes - 1);
        buf = devm_kzalloc(ice_hw_to_dev(hw), buf_size, GFP_KERNEL);
        if (!buf)
                return ICE_ERR_NO_MEMORY;