[PATCH] net: dsa: hellcreek: Constify struct devlink_region_ops and struct hellcreek_fdb_entry

From: Christophe JAILLET
Date: Sun Jun 29 2025 - 17:08:09 EST


'struct devlink_region_ops' and 'struct hellcreek_fdb_entry' are not
modified in this driver.

Constifying these structures moves some data to a read-only section, so
increases overall security, especially when the structure holds some
function pointers.

On a x86_64, with allmodconfig:
Before:
======
text data bss dec hex filename
55320 19216 320 74856 12468 drivers/net/dsa/hirschmann/hellcreek.o

After:
=====
text data bss dec hex filename
55960 18576 320 74856 12468 drivers/net/dsa/hirschmann/hellcreek.o

Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
---
Compile tested only
---
drivers/net/dsa/hirschmann/hellcreek.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/net/dsa/hirschmann/hellcreek.c b/drivers/net/dsa/hirschmann/hellcreek.c
index 283ec5a6e23c..e0b4758ca583 100644
--- a/drivers/net/dsa/hirschmann/hellcreek.c
+++ b/drivers/net/dsa/hirschmann/hellcreek.c
@@ -1061,7 +1061,7 @@ static void hellcreek_setup_tc_identity_mapping(struct hellcreek *hellcreek)

static int hellcreek_setup_fdb(struct hellcreek *hellcreek)
{
- static struct hellcreek_fdb_entry l2_ptp = {
+ static const struct hellcreek_fdb_entry l2_ptp = {
/* MAC: 01-1B-19-00-00-00 */
.mac = { 0x01, 0x1b, 0x19, 0x00, 0x00, 0x00 },
.portmask = 0x03, /* Management ports */
@@ -1072,7 +1072,7 @@ static int hellcreek_setup_fdb(struct hellcreek *hellcreek)
.reprio_tc = 6, /* TC: 6 as per IEEE 802.1AS */
.reprio_en = 1,
};
- static struct hellcreek_fdb_entry udp4_ptp = {
+ static const struct hellcreek_fdb_entry udp4_ptp = {
/* MAC: 01-00-5E-00-01-81 */
.mac = { 0x01, 0x00, 0x5e, 0x00, 0x01, 0x81 },
.portmask = 0x03, /* Management ports */
@@ -1083,7 +1083,7 @@ static int hellcreek_setup_fdb(struct hellcreek *hellcreek)
.reprio_tc = 6,
.reprio_en = 1,
};
- static struct hellcreek_fdb_entry udp6_ptp = {
+ static const struct hellcreek_fdb_entry udp6_ptp = {
/* MAC: 33-33-00-00-01-81 */
.mac = { 0x33, 0x33, 0x00, 0x00, 0x01, 0x81 },
.portmask = 0x03, /* Management ports */
@@ -1094,7 +1094,7 @@ static int hellcreek_setup_fdb(struct hellcreek *hellcreek)
.reprio_tc = 6,
.reprio_en = 1,
};
- static struct hellcreek_fdb_entry l2_p2p = {
+ static const struct hellcreek_fdb_entry l2_p2p = {
/* MAC: 01-80-C2-00-00-0E */
.mac = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x0e },
.portmask = 0x03, /* Management ports */
@@ -1105,7 +1105,7 @@ static int hellcreek_setup_fdb(struct hellcreek *hellcreek)
.reprio_tc = 6, /* TC: 6 as per IEEE 802.1AS */
.reprio_en = 1,
};
- static struct hellcreek_fdb_entry udp4_p2p = {
+ static const struct hellcreek_fdb_entry udp4_p2p = {
/* MAC: 01-00-5E-00-00-6B */
.mac = { 0x01, 0x00, 0x5e, 0x00, 0x00, 0x6b },
.portmask = 0x03, /* Management ports */
@@ -1116,7 +1116,7 @@ static int hellcreek_setup_fdb(struct hellcreek *hellcreek)
.reprio_tc = 6,
.reprio_en = 1,
};
- static struct hellcreek_fdb_entry udp6_p2p = {
+ static const struct hellcreek_fdb_entry udp6_p2p = {
/* MAC: 33-33-00-00-00-6B */
.mac = { 0x33, 0x33, 0x00, 0x00, 0x00, 0x6b },
.portmask = 0x03, /* Management ports */
@@ -1127,7 +1127,7 @@ static int hellcreek_setup_fdb(struct hellcreek *hellcreek)
.reprio_tc = 6,
.reprio_en = 1,
};
- static struct hellcreek_fdb_entry stp = {
+ static const struct hellcreek_fdb_entry stp = {
/* MAC: 01-80-C2-00-00-00 */
.mac = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 },
.portmask = 0x03, /* Management ports */
@@ -1320,13 +1320,13 @@ static int hellcreek_devlink_region_fdb_snapshot(struct devlink *dl,
return 0;
}

-static struct devlink_region_ops hellcreek_region_vlan_ops = {
+static const struct devlink_region_ops hellcreek_region_vlan_ops = {
.name = "vlan",
.snapshot = hellcreek_devlink_region_vlan_snapshot,
.destructor = kfree,
};

-static struct devlink_region_ops hellcreek_region_fdb_ops = {
+static const struct devlink_region_ops hellcreek_region_fdb_ops = {
.name = "fdb",
.snapshot = hellcreek_devlink_region_fdb_snapshot,
.destructor = kfree,
@@ -1335,7 +1335,7 @@ static struct devlink_region_ops hellcreek_region_fdb_ops = {
static int hellcreek_setup_devlink_regions(struct dsa_switch *ds)
{
struct hellcreek *hellcreek = ds->priv;
- struct devlink_region_ops *ops;
+ const struct devlink_region_ops *ops;
struct devlink_region *region;
u64 size;
int ret;
--
2.50.0