[PATCH v8 net-next 6/8] ipv6tlvs: opt_update function

[Tom Herbert]

Add a utility function to replace socket's options with a new set.

Signed-off-by: Tom Herbert <t...@quantonium.net>
---
 include/net/ipv6.h       |  2 ++
 net/ipv6/ipv6_sockglue.c | 16 ++++++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 8c19c6f..a8c1e6c 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -379,6 +379,8 @@ struct ipv6_txoptions *ipv6_renew_options(struct sock *sk,
                                          struct ipv6_opt_hdr *newopt);
 struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
                                          struct ipv6_txoptions *opt);
+int ipv6_opt_update(struct sock *sk, struct ipv6_txoptions *opt,
+                   int which, struct ipv6_opt_hdr *new);
 
 /*
  *     Parsing tlv encoded headers.
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 5045818..b8ef0ea 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -118,6 +118,22 @@ struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
        return opt;
 }
 
+int ipv6_opt_update(struct sock *sk, struct ipv6_txoptions *opt,
+                   int which, struct ipv6_opt_hdr *new)
+{
+       opt = ipv6_renew_options(sk, opt, which, new);
+       if (IS_ERR(opt))
+               return PTR_ERR(opt);
+
+       opt = ipv6_update_options(sk, opt);
+       if (opt) {
+               atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
+               txopt_put(opt);
+       }
+
+       return 0;
+}
+
 static bool setsockopt_needs_rtnl(int optname)
 {
        switch (optname) {
-- 
2.7.4