[PATCH net-next 15/15] ethtool: add CHANNELS_NTF notification

From: Michal Kubecek
Date: Wed Mar 11 2020 - 17:41:24 EST


Send ETHTOOL_MSG_CHANNELS_NTF notification whenever channel counts of
a network device are modified using ETHTOOL_MSG_CHANNELS_SET netlink
message or ETHTOOL_SCHANNELS ioctl request.

Signed-off-by: Michal Kubecek <mkubecek@xxxxxxx>
---
Documentation/networking/ethtool-netlink.rst | 1 +
include/uapi/linux/ethtool_netlink.h | 1 +
net/ethtool/channels.c | 3 +++
net/ethtool/ioctl.c | 6 +++++-
net/ethtool/netlink.c | 2 ++
5 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index 7df7476cf310..31a601cafa3f 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -220,6 +220,7 @@ Kernel to userspace:
``ETHTOOL_MSG_RINGS_GET_REPLY`` ring sizes
``ETHTOOL_MSG_RINGS_NTF`` ring sizes
``ETHTOOL_MSG_CHANNELS_GET_REPLY`` channel counts
+ ``ETHTOOL_MSG_CHANNELS_NTF`` channel counts
===================================== =================================

``GET`` requests are sent by userspace applications to retrieve device
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index f1384a8f3534..c7c7a1a550af 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -59,6 +59,7 @@ enum {
ETHTOOL_MSG_RINGS_GET_REPLY,
ETHTOOL_MSG_RINGS_NTF,
ETHTOOL_MSG_CHANNELS_GET_REPLY,
+ ETHTOOL_MSG_CHANNELS_NTF,

/* add new constants above here */
__ETHTOOL_MSG_KERNEL_CNT,
diff --git a/net/ethtool/channels.c b/net/ethtool/channels.c
index 412b6380766d..04d1a75a55c7 100644
--- a/net/ethtool/channels.c
+++ b/net/ethtool/channels.c
@@ -203,6 +203,9 @@ int ethnl_set_channels(struct sk_buff *skb, struct genl_info *info)
}

ret = dev->ethtool_ops->set_channels(dev, &channels);
+ if (ret < 0)
+ goto out_ops;
+ ethtool_notify(dev, ETHTOOL_MSG_CHANNELS_NTF, NULL);

out_ops:
ethnl_ops_complete(dev);
diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index 06224a03139e..258840b19fb5 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -1649,6 +1649,7 @@ static noinline_for_stack int ethtool_set_channels(struct net_device *dev,
u16 from_channel, to_channel;
u32 max_rx_in_use = 0;
unsigned int i;
+ int ret;

if (!dev->ethtool_ops->set_channels || !dev->ethtool_ops->get_channels)
return -EOPNOTSUPP;
@@ -1680,7 +1681,10 @@ static noinline_for_stack int ethtool_set_channels(struct net_device *dev,
if (xdp_get_umem_from_qid(dev, i))
return -EINVAL;

- return dev->ethtool_ops->set_channels(dev, &channels);
+ ret = dev->ethtool_ops->set_channels(dev, &channels);
+ if (!ret)
+ ethtool_notify(dev, ETHTOOL_MSG_CHANNELS_NTF, NULL);
+ return ret;
}

static int ethtool_get_pauseparam(struct net_device *dev, void __user *useraddr)
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index f61654b8f210..55c8ce4019d9 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -534,6 +534,7 @@ ethnl_default_notify_ops[ETHTOOL_MSG_KERNEL_MAX + 1] = {
[ETHTOOL_MSG_FEATURES_NTF] = &ethnl_features_request_ops,
[ETHTOOL_MSG_PRIVFLAGS_NTF] = &ethnl_privflags_request_ops,
[ETHTOOL_MSG_RINGS_NTF] = &ethnl_rings_request_ops,
+ [ETHTOOL_MSG_CHANNELS_NTF] = &ethnl_channels_request_ops,
};

/* default notification handler */
@@ -622,6 +623,7 @@ static const ethnl_notify_handler_t ethnl_notify_handlers[] = {
[ETHTOOL_MSG_FEATURES_NTF] = ethnl_default_notify,
[ETHTOOL_MSG_PRIVFLAGS_NTF] = ethnl_default_notify,
[ETHTOOL_MSG_RINGS_NTF] = ethnl_default_notify,
+ [ETHTOOL_MSG_CHANNELS_NTF] = ethnl_default_notify,
};

void ethtool_notify(struct net_device *dev, unsigned int cmd, const void *data)
--
2.25.1