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| author |   Florian Westphal <fw@strlen.de> | 2017-08-09 20:41:52 +0200 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2017-08-09 16:57:38 -0700 |
| commit | 62256f98f244fbb1c7a10465e1ee412f209d8978 (patch) | |
| tree | 89b1dff314d7b5fd1e10c24ef3971f51abe9c624 /net/core | |
| parent | rtnetlink: protect handler table with rcu (diff) | |
| download | linux-dev-62256f98f244fbb1c7a10465e1ee412f209d8978.tar.xz linux-dev-62256f98f244fbb1c7a10465e1ee412f209d8978.zip | |
rtnetlink: add RTNL_FLAG_DOIT_UNLOCKED
Allow callers to tell rtnetlink core that its doit callback
should be invoked without holding rtnl mutex.
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/rtnetlink.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index d45946177bc8..dd4e50dfa248 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -62,6 +62,7 @@ struct rtnl_link { rtnl_doit_func doit; rtnl_dumpit_func dumpit; + unsigned int flags; }; static DEFINE_MUTEX(rtnl_mutex); @@ -184,6 +185,7 @@ int __rtnl_register(int protocol, int msgtype, tab[msgindex].doit = doit; if (dumpit) tab[msgindex].dumpit = dumpit; + tab[msgindex].flags |= flags; return 0; } @@ -233,6 +235,7 @@ int rtnl_unregister(int protocol, int msgtype) handlers[msgindex].doit = NULL; handlers[msgindex].dumpit = NULL; + handlers[msgindex].flags = 0; rtnl_unlock(); return 0; @@ -4143,6 +4146,7 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, struct rtnl_link *handlers; int err = -EOPNOTSUPP; rtnl_doit_func doit; + unsigned int flags; int kind; int family; int type; @@ -4209,6 +4213,17 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, return err; } + flags = READ_ONCE(handlers[type].flags); + if (flags & RTNL_FLAG_DOIT_UNLOCKED) { + refcount_inc(&rtnl_msg_handlers_ref[family]); + doit = READ_ONCE(handlers[type].doit); + rcu_read_unlock(); + if (doit) + err = doit(skb, nlh, extack); + refcount_dec(&rtnl_msg_handlers_ref[family]); + return err; + } + rcu_read_unlock(); rtnl_lock(); |