From f9496b7c1b48ce02cd17a3ee88b1e049c689a222 Mon Sep 17 00:00:00 2001 From: "D. Wythe" Date: Thu, 10 Feb 2022 17:11:38 +0800 Subject: net/smc: Add global configure for handshake limitation by netlink Although we can control SMC handshake limitation through socket options, which means that applications who need it must modify their code. It's quite troublesome for many existing applications. This patch modifies the global default value of SMC handshake limitation through netlink, providing a way to put constraint on handshake without modifies any code for applications. Suggested-by: Tony Lu Signed-off-by: D. Wythe Reviewed-by: Tony Lu Signed-off-by: David S. Miller --- net/smc/af_smc.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) (limited to 'net/smc/af_smc.c') diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 97dcdc0a2107..246c874de629 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -66,6 +66,45 @@ struct workqueue_struct *smc_close_wq; /* wq for close work */ static void smc_tcp_listen_work(struct work_struct *); static void smc_connect_work(struct work_struct *); +int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb); + void *hdr; + + if (cb_ctx->pos[0]) + goto out; + + hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, + &smc_gen_nl_family, NLM_F_MULTI, + SMC_NETLINK_DUMP_HS_LIMITATION); + if (!hdr) + return -ENOMEM; + + if (nla_put_u8(skb, SMC_NLA_HS_LIMITATION_ENABLED, + sock_net(skb->sk)->smc.limit_smc_hs)) + goto err; + + genlmsg_end(skb, hdr); + cb_ctx->pos[0] = 1; +out: + return skb->len; +err: + genlmsg_cancel(skb, hdr); + return -EMSGSIZE; +} + +int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info) +{ + sock_net(skb->sk)->smc.limit_smc_hs = true; + return 0; +} + +int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info) +{ + sock_net(skb->sk)->smc.limit_smc_hs = false; + return 0; +} + static void smc_set_keepalive(struct sock *sk, int val) { struct smc_sock *smc = smc_sk(sk); @@ -3007,6 +3046,9 @@ static int __smc_create(struct net *net, struct socket *sock, int protocol, smc->use_fallback = false; /* assume rdma capability first */ smc->fallback_rsn = 0; + /* default behavior from limit_smc_hs in every net namespace */ + smc->limit_smc_hs = net->smc.limit_smc_hs; + rc = 0; if (!clcsock) { rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP, -- cgit v1.2.3