Implement the three ethtool loopback ops for MAC-level loopback
simulation:
- get_loopback(): exact lookup by name ("mac")
- get_loopback_by()_index: enumerate (single entry at index 0)
- set_loopback(): update direction, return 1 if changed
The MAC loopback entry announces support for both near-end and far-end
support by default. State is stored in nsim_ethtool.mac_lb and exposed
via debugfs under ethtool/mac_lb/{supported,direction} for test
inspection and control.
Signed-off-by: Björn Töpel <[email protected]>
---
drivers/net/netdevsim/ethtool.c | 64 +++++++++++++++++++++++++++++++
drivers/net/netdevsim/netdevsim.h | 4 ++
2 files changed, 68 insertions(+)
diff --git a/drivers/net/netdevsim/ethtool.c b/drivers/net/netdevsim/ethtool.c
index 36a201533aae..84bc025885f7 100644
--- a/drivers/net/netdevsim/ethtool.c
+++ b/drivers/net/netdevsim/ethtool.c
@@ -195,6 +195,58 @@ nsim_get_fec_stats(struct net_device *dev, struct
ethtool_fec_stats *fec_stats,
values[2].per_lane[3] = 0;
}
+static void nsim_fill_mac_lb_entry(struct netdevsim *ns,
+ struct ethtool_loopback_entry *entry)
+{
+ memset(entry, 0, sizeof(*entry));
+ entry->component = ETHTOOL_LOOPBACK_COMPONENT_MAC;
+ strscpy(entry->name, "mac", sizeof(entry->name));
+ entry->supported = ns->ethtool.mac_lb.supported;
+ entry->direction = ns->ethtool.mac_lb.direction;
+}
+
+static int nsim_get_loopback(struct net_device *dev, const char *name,
+ u32 id, struct ethtool_loopback_entry *entry)
+{
+ struct netdevsim *ns = netdev_priv(dev);
+
+ if (strcmp(name, "mac"))
+ return -EOPNOTSUPP;
+
+ nsim_fill_mac_lb_entry(ns, entry);
+ return 0;
+}
+
+static int nsim_get_loopback_by_index(struct net_device *dev, u32 index,
+ struct ethtool_loopback_entry *entry)
+{
+ struct netdevsim *ns = netdev_priv(dev);
+
+ if (index > 0)
+ return -EOPNOTSUPP;
+
+ nsim_fill_mac_lb_entry(ns, entry);
+ return 0;
+}
+
+static int nsim_set_loopback(struct net_device *dev,
+ const struct ethtool_loopback_entry *entry,
+ struct netlink_ext_ack *extack)
+{
+ struct netdevsim *ns = netdev_priv(dev);
+
+ if (strcmp(entry->name, "mac")) {
+ NL_SET_ERR_MSG(extack, "Unknown MAC loopback name");
+ return -EOPNOTSUPP;
+ }
+
+ if (ns->ethtool.mac_lb.direction == entry->direction)
+ return 0;
+
+ ns->ethtool.mac_lb.direction = entry->direction;
+ return 1;
+}
+
static int nsim_get_ts_info(struct net_device *dev,
struct kernel_ethtool_ts_info *info)
{
@@ -222,6 +274,9 @@ static const struct ethtool_ops nsim_ethtool_ops = {
.set_fecparam = nsim_set_fecparam,
.get_fec_stats = nsim_get_fec_stats,
.get_ts_info = nsim_get_ts_info,
+ .get_loopback = nsim_get_loopback,
+ .get_loopback_by_index = nsim_get_loopback_by_index,
+ .set_loopback = nsim_set_loopback,
};
static void nsim_ethtool_ring_init(struct netdevsim *ns)
@@ -270,4 +325,13 @@ void nsim_ethtool_init(struct netdevsim *ns)
&ns->ethtool.ring.rx_mini_max_pending);
debugfs_create_u32("tx_max_pending", 0600, dir,
&ns->ethtool.ring.tx_max_pending);
+
+ ns->ethtool.mac_lb.supported = ETHTOOL_LOOPBACK_DIRECTION_NEAR_END |
+ ETHTOOL_LOOPBACK_DIRECTION_FAR_END;
+
+ dir = debugfs_create_dir("mac_lb", ethtool);
+ debugfs_create_u32("supported", 0600, dir,
+ &ns->ethtool.mac_lb.supported);
+ debugfs_create_u32("direction", 0600, dir,
+ &ns->ethtool.mac_lb.direction);
}
diff --git a/drivers/net/netdevsim/netdevsim.h
b/drivers/net/netdevsim/netdevsim.h
index f767fc8a7505..2e322b9410d2 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -90,6 +90,10 @@ struct nsim_ethtool {
struct ethtool_coalesce coalesce;
struct ethtool_ringparam ring;
struct ethtool_fecparam fec;
+ struct {
+ u32 supported;
+ u32 direction;
+ } mac_lb;
};
struct nsim_rq {
--
2.53.0
