[PATCH net-next 1/4] net: dsa: remove copy of master ethtool_ops

From: Vivien Didelot
Date: Tue Sep 19 2017 - 12:00:56 EST


There is no need to store a copy of the master ethtool ops, storing the
original pointer in DSA and the new one in the master netdev itself is
enough.

In the meantime, set orig_ethtool_ops to NULL when restoring the master
ethtool ops and check the presence of the master original ethtool ops as
well as its needed functions before calling them.

Signed-off-by: Vivien Didelot <vivien.didelot@xxxxxxxxxxxxxxxxxxxx>
---
include/net/dsa.h | 1 -
net/dsa/dsa.c | 8 ++++----
net/dsa/slave.c | 19 +++++++++++--------
3 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/include/net/dsa.h b/include/net/dsa.h
index dd44d6ce1097..8dee216a5a9b 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -188,7 +188,6 @@ struct dsa_port {
/*
* Original copy of the master netdev ethtool_ops
*/
- struct ethtool_ops ethtool_ops;
const struct ethtool_ops *orig_ethtool_ops;
};

diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 03c58b0eb082..abadf7b49236 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -124,11 +124,10 @@ int dsa_cpu_port_ethtool_setup(struct dsa_port *cpu_dp)
if (!cpu_ops)
return -ENOMEM;

- memcpy(&cpu_dp->ethtool_ops, master->ethtool_ops,
- sizeof(struct ethtool_ops));
cpu_dp->orig_ethtool_ops = master->ethtool_ops;
- memcpy(cpu_ops, &cpu_dp->ethtool_ops,
- sizeof(struct ethtool_ops));
+ if (cpu_dp->orig_ethtool_ops)
+ memcpy(cpu_ops, cpu_dp->orig_ethtool_ops, sizeof(*cpu_ops));
+
dsa_cpu_port_ethtool_init(cpu_ops);
master->ethtool_ops = cpu_ops;

@@ -138,6 +137,7 @@ int dsa_cpu_port_ethtool_setup(struct dsa_port *cpu_dp)
void dsa_cpu_port_ethtool_restore(struct dsa_port *cpu_dp)
{
cpu_dp->netdev->ethtool_ops = cpu_dp->orig_ethtool_ops;
+ cpu_dp->orig_ethtool_ops = NULL;
}

void dsa_cpu_dsa_destroy(struct dsa_port *port)
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 2afa99506f8b..2ff4f907d137 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -574,12 +574,13 @@ static void dsa_cpu_port_get_ethtool_stats(struct net_device *dev,
struct dsa_switch_tree *dst = dev->dsa_ptr;
struct dsa_port *cpu_dp = dsa_get_cpu_port(dst);
struct dsa_switch *ds = cpu_dp->ds;
+ const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
s8 cpu_port = cpu_dp->index;
int count = 0;

- if (cpu_dp->ethtool_ops.get_sset_count) {
- count = cpu_dp->ethtool_ops.get_sset_count(dev, ETH_SS_STATS);
- cpu_dp->ethtool_ops.get_ethtool_stats(dev, stats, data);
+ if (ops && ops->get_sset_count && ops->get_ethtool_stats) {
+ count = ops->get_sset_count(dev, ETH_SS_STATS);
+ ops->get_ethtool_stats(dev, stats, data);
}

if (ds->ops->get_ethtool_stats)
@@ -591,10 +592,11 @@ static int dsa_cpu_port_get_sset_count(struct net_device *dev, int sset)
struct dsa_switch_tree *dst = dev->dsa_ptr;
struct dsa_port *cpu_dp = dsa_get_cpu_port(dst);
struct dsa_switch *ds = cpu_dp->ds;
+ const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
int count = 0;

- if (cpu_dp->ethtool_ops.get_sset_count)
- count += cpu_dp->ethtool_ops.get_sset_count(dev, sset);
+ if (ops && ops->get_sset_count)
+ count += ops->get_sset_count(dev, sset);

if (sset == ETH_SS_STATS && ds->ops->get_sset_count)
count += ds->ops->get_sset_count(ds);
@@ -608,6 +610,7 @@ static void dsa_cpu_port_get_strings(struct net_device *dev,
struct dsa_switch_tree *dst = dev->dsa_ptr;
struct dsa_port *cpu_dp = dsa_get_cpu_port(dst);
struct dsa_switch *ds = cpu_dp->ds;
+ const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
s8 cpu_port = cpu_dp->index;
int len = ETH_GSTRING_LEN;
int mcount = 0, count;
@@ -619,9 +622,9 @@ static void dsa_cpu_port_get_strings(struct net_device *dev,
/* We do not want to be NULL-terminated, since this is a prefix */
pfx[sizeof(pfx) - 1] = '_';

- if (cpu_dp->ethtool_ops.get_sset_count) {
- mcount = cpu_dp->ethtool_ops.get_sset_count(dev, ETH_SS_STATS);
- cpu_dp->ethtool_ops.get_strings(dev, stringset, data);
+ if (ops && ops->get_sset_count && ops->get_strings) {
+ mcount = ops->get_sset_count(dev, ETH_SS_STATS);
+ ops->get_strings(dev, stringset, data);
}

if (stringset == ETH_SS_STATS && ds->ops->get_strings) {
--
2.14.1