[PATCH 1/2] rtnetlink: use nlmsg_{multicast, unicast} instead of netlink_{broadcast,unicast}

Yajun Deng
2021-07-13T12:37:37Z

It has a 'NETLINK_CB(' statement in nlmsg_multicast() and has 'if (err'
in nlmsg_{multicast, unicast}, use nlmsg_{multicast, unicast} instead
of netlink_{broadcast,unicast}. so the caller would not deal with the
'if (err >0 )' statement. Add the return value for nlmsg_multicast.
As also, rename rtnetlink_send() to rtnl_send(), this makes style
uniform.

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
---
include/linux/rtnetlink.h | 2 +-
net/core/rtnetlink.c | 13 +++++++------
2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h
index bb9cb84114c1..60bef82e42ab 100644
--- a/include/linux/rtnetlink.h
+++ b/include/linux/rtnetlink.h
@@ -9,7 +9,7 @@
#include <linux/refcount.h>
#include <uapi/linux/rtnetlink.h>

-extern int rtnetlink_send(struct sk_buff *skb, struct net *net, u32 pid, u32 group, int echo);
+extern int rtnl_send(struct sk_buff *skb, struct net *net, u32 pid, u32 group, int echo);
extern int rtnl_unicast(struct sk_buff *skb, struct net *net, u32 pid);
extern void rtnl_notify(struct sk_buff *skb, struct net *net, u32 pid,
u32 group, struct nlmsghdr *nlh, gfp_t flags);
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index f6af3e74fc44..c081d607bb69 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -707,17 +707,18 @@ static int rtnl_link_fill(struct sk_buff *skb, const struct net_device *dev)
return err;
}

-int rtnetlink_send(struct sk_buff *skb, struct net *net, u32 pid, unsigned int group, int echo)
+int rtnl_send(struct sk_buff *skb, struct net *net, u32 pid, unsigned int group, int echo)
{
struct sock *rtnl = net->rtnl;
int err = 0;

- NETLINK_CB(skb).dst_group = group;
- if (echo)
+ err = nlmsg_multicast(rtnl, skb, pid, group, GFP_KERNEL);
+
+ if (echo) {
refcount_inc(&skb->users);
- netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
- if (echo)
- err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
+ err = nlmsg_unicast(rtnl, skb, pid);
+ }
+
return err;
}

--
2.32.0