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 = kzalloc(size, GFP_KERNEL);
Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:
instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);
Notice that, in this case, variable table_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/gpu/drm/amd/powerplay/hwmgr/smu8_hwmgr.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/amd/powerplay/hwmgr/smu8_hwmgr.c
b/drivers/gpu/drm/amd/powerplay/hwmgr/smu8_hwmgr.c
index 553a203ac47c..019d6a206492 100644
--- a/drivers/gpu/drm/amd/powerplay/hwmgr/smu8_hwmgr.c
+++ b/drivers/gpu/drm/amd/powerplay/hwmgr/smu8_hwmgr.c
@@ -272,12 +272,10 @@ static int
smu8_init_dynamic_state_adjustment_rule_settings(
struct pp_hwmgr *hwmgr,
ATOM_CLK_VOLT_CAPABILITY *disp_voltage_table)
{
- uint32_t table_size =
- sizeof(struct phm_clock_voltage_dependency_table) +
- (7 * sizeof(struct phm_clock_voltage_dependency_record));
+ struct phm_clock_voltage_dependency_table *table_clk_vlt;
- struct phm_clock_voltage_dependency_table *table_clk_vlt =
- kzalloc(table_size, GFP_KERNEL);
+ table_clk_vlt = kzalloc(struct_size(table_clk_vlt, entries, 7),
+ GFP_KERNEL);
if (NULL == table_clk_vlt) {
pr_err("Can not allocate memory!\n");
--
2.20.1
