diff mbox series

[net-next,v4,2/3] net: advertise netns_immutable property via netlink

Message ID 20250221133136.2049165-3-nicolas.dichtel@6wind.com (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series net: notify users when an iface cannot change its netns | expand

Commit Message

Nicolas Dichtel Feb. 21, 2025, 1:30 p.m. UTC
Since commit 05c1280a2bcf ("netdev_features: convert NETIF_F_NETNS_LOCAL to
dev->netns_local"), there is no way to see if the netns_immutable property
s set on a device. Let's add a netlink attribute to advertise it.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
---
 Documentation/netlink/specs/rt_link.yaml | 3 +++
 include/uapi/linux/if_link.h             | 1 +
 net/core/rtnetlink.c                     | 3 +++
 3 files changed, 7 insertions(+)
diff mbox series

Patch

diff --git a/Documentation/netlink/specs/rt_link.yaml b/Documentation/netlink/specs/rt_link.yaml
index 0d492500c7e5..d13b14c6b9d7 100644
--- a/Documentation/netlink/specs/rt_link.yaml
+++ b/Documentation/netlink/specs/rt_link.yaml
@@ -1148,6 +1148,9 @@  attribute-sets:
         name: max-pacing-offload-horizon
         type: uint
         doc: EDT offload horizon supported by the device (in nsec).
+      -
+        name: netns-immutable
+        type: u8
   -
     name: af-spec-attrs
     attributes:
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index bfe880fbbb24..a2b6cfde7162 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -378,6 +378,7 @@  enum {
 	IFLA_GRO_IPV4_MAX_SIZE,
 	IFLA_DPLL_PIN,
 	IFLA_MAX_PACING_OFFLOAD_HORIZON,
+	IFLA_NETNS_IMMUTABLE,
 	__IFLA_MAX
 };
 
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index abe1a461ea67..a76f63b926df 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1292,6 +1292,7 @@  static noinline size_t if_nlmsg_size(const struct net_device *dev,
 	       + nla_total_size(4) /* IFLA_TSO_MAX_SEGS */
 	       + nla_total_size(1) /* IFLA_OPERSTATE */
 	       + nla_total_size(1) /* IFLA_LINKMODE */
+	       + nla_total_size(1) /* IFLA_NETNS_IMMUTABLE */
 	       + nla_total_size(4) /* IFLA_CARRIER_CHANGES */
 	       + nla_total_size(4) /* IFLA_LINK_NETNSID */
 	       + nla_total_size(4) /* IFLA_GROUP */
@@ -2046,6 +2047,7 @@  static int rtnl_fill_ifinfo(struct sk_buff *skb,
 		       netif_running(dev) ? READ_ONCE(dev->operstate) :
 					    IF_OPER_DOWN) ||
 	    nla_put_u8(skb, IFLA_LINKMODE, READ_ONCE(dev->link_mode)) ||
+	    nla_put_u8(skb, IFLA_NETNS_IMMUTABLE, dev->netns_immutable) ||
 	    nla_put_u32(skb, IFLA_MTU, READ_ONCE(dev->mtu)) ||
 	    nla_put_u32(skb, IFLA_MIN_MTU, READ_ONCE(dev->min_mtu)) ||
 	    nla_put_u32(skb, IFLA_MAX_MTU, READ_ONCE(dev->max_mtu)) ||
@@ -2234,6 +2236,7 @@  static const struct nla_policy ifla_policy[IFLA_MAX+1] = {
 	[IFLA_ALLMULTI]		= { .type = NLA_REJECT },
 	[IFLA_GSO_IPV4_MAX_SIZE]	= NLA_POLICY_MIN(NLA_U32, MAX_TCP_HEADER + 1),
 	[IFLA_GRO_IPV4_MAX_SIZE]	= { .type = NLA_U32 },
+	[IFLA_NETNS_IMMUTABLE]	= { .type = NLA_REJECT },
 };
 
 static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {