From b4cb4a1391dcdc640c4ade003aaf0ee19cc8d509 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 4 Jun 2024 11:16:03 +0000 Subject: [PATCH] net: use unrcu_pointer() helper MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Toke mentioned unrcu_pointer() existence, allowing to remove some of the ugly casts we have when using xchg() for rcu protected pointers. Also make inet_rcv_compat const. Signed-off-by: Eric Dumazet Cc: Toke Høiland-Jørgensen Reviewed-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/r/20240604111603.45871-1-edumazet@google.com Signed-off-by: Paolo Abeni --- include/net/sock.h | 2 +- net/core/gen_estimator.c | 2 +- net/core/sock_diag.c | 8 +++----- net/ipv4/cipso_ipv4.c | 2 +- net/ipv4/tcp.c | 2 +- net/ipv4/tcp_fastopen.c | 7 ++++--- net/ipv4/udp.c | 2 +- net/ipv6/af_inet6.c | 2 +- net/ipv6/ip6_fib.c | 2 +- net/ipv6/ipv6_sockglue.c | 3 +-- net/ipv6/route.c | 6 +++--- net/sched/act_api.c | 2 +- 12 files changed, 19 insertions(+), 21 deletions(-) diff --git a/include/net/sock.h b/include/net/sock.h index 953c8dc4e259..b30ea0c342a6 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -2095,7 +2095,7 @@ sk_dst_set(struct sock *sk, struct dst_entry *dst) sk_tx_queue_clear(sk); WRITE_ONCE(sk->sk_dst_pending_confirm, 0); - old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst); + old_dst = unrcu_pointer(xchg(&sk->sk_dst_cache, RCU_INITIALIZER(dst))); dst_release(old_dst); } diff --git a/net/core/gen_estimator.c b/net/core/gen_estimator.c index fae9c4694186..412816076b8b 100644 --- a/net/core/gen_estimator.c +++ b/net/core/gen_estimator.c @@ -206,7 +206,7 @@ void gen_kill_estimator(struct net_rate_estimator __rcu **rate_est) { struct net_rate_estimator *est; - est = xchg((__force struct net_rate_estimator **)rate_est, NULL); + est = unrcu_pointer(xchg(rate_est, NULL)); if (est) { timer_shutdown_sync(&est->timer); kfree_rcu(est, rcu); diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c index 654122838025..a08eed9b9142 100644 --- a/net/core/sock_diag.c +++ b/net/core/sock_diag.c @@ -18,7 +18,7 @@ static const struct sock_diag_handler __rcu *sock_diag_handlers[AF_MAX]; -static struct sock_diag_inet_compat __rcu *inet_rcv_compat; +static const struct sock_diag_inet_compat __rcu *inet_rcv_compat; static struct workqueue_struct *broadcast_wq; @@ -187,8 +187,7 @@ void sock_diag_broadcast_destroy(struct sock *sk) void sock_diag_register_inet_compat(const struct sock_diag_inet_compat *ptr) { - xchg((__force const struct sock_diag_inet_compat **)&inet_rcv_compat, - ptr); + xchg(&inet_rcv_compat, RCU_INITIALIZER(ptr)); } EXPORT_SYMBOL_GPL(sock_diag_register_inet_compat); @@ -196,8 +195,7 @@ void sock_diag_unregister_inet_compat(const struct sock_diag_inet_compat *ptr) { const struct sock_diag_inet_compat *old; - old = xchg((__force const struct sock_diag_inet_compat **)&inet_rcv_compat, - NULL); + old = unrcu_pointer(xchg(&inet_rcv_compat, NULL)); WARN_ON_ONCE(old != ptr); } EXPORT_SYMBOL_GPL(sock_diag_unregister_inet_compat); diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c index dd6d46015058..3a95c0f13ce3 100644 --- a/net/ipv4/cipso_ipv4.c +++ b/net/ipv4/cipso_ipv4.c @@ -1953,7 +1953,7 @@ int cipso_v4_req_setattr(struct request_sock *req, buf = NULL; req_inet = inet_rsk(req); - opt = xchg((__force struct ip_options_rcu **)&req_inet->ireq_opt, opt); + opt = unrcu_pointer(xchg(&req_inet->ireq_opt, RCU_INITIALIZER(opt))); if (opt) kfree_rcu(opt, rcu); diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index fa43aaacd92b..f727bc8d82a6 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3081,7 +3081,7 @@ int tcp_disconnect(struct sock *sk, int flags) icsk->icsk_ack.rcv_mss = TCP_MIN_MSS; memset(&tp->rx_opt, 0, sizeof(tp->rx_opt)); __sk_dst_reset(sk); - dst_release(xchg((__force struct dst_entry **)&sk->sk_rx_dst, NULL)); + dst_release(unrcu_pointer(xchg(&sk->sk_rx_dst, NULL))); tcp_saved_syn_free(tp); tp->compressed_ack = 0; tp->segs_in = 0; diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c index 8ed54e7334a9..0f523cbfe329 100644 --- a/net/ipv4/tcp_fastopen.c +++ b/net/ipv4/tcp_fastopen.c @@ -49,7 +49,7 @@ void tcp_fastopen_ctx_destroy(struct net *net) { struct tcp_fastopen_context *ctxt; - ctxt = xchg((__force struct tcp_fastopen_context **)&net->ipv4.tcp_fastopen_ctx, NULL); + ctxt = unrcu_pointer(xchg(&net->ipv4.tcp_fastopen_ctx, NULL)); if (ctxt) call_rcu(&ctxt->rcu, tcp_fastopen_ctx_free); @@ -80,9 +80,10 @@ int tcp_fastopen_reset_cipher(struct net *net, struct sock *sk, if (sk) { q = &inet_csk(sk)->icsk_accept_queue.fastopenq; - octx = xchg((__force struct tcp_fastopen_context **)&q->ctx, ctx); + octx = unrcu_pointer(xchg(&q->ctx, RCU_INITIALIZER(ctx))); } else { - octx = xchg((__force struct tcp_fastopen_context **)&net->ipv4.tcp_fastopen_ctx, ctx); + octx = unrcu_pointer(xchg(&net->ipv4.tcp_fastopen_ctx, + RCU_INITIALIZER(ctx))); } if (octx) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 189c9113fe9a..c9ca6d285347 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -2230,7 +2230,7 @@ bool udp_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst) struct dst_entry *old; if (dst_hold_safe(dst)) { - old = xchg((__force struct dst_entry **)&sk->sk_rx_dst, dst); + old = unrcu_pointer(xchg(&sk->sk_rx_dst, RCU_INITIALIZER(dst))); dst_release(old); return old != dst; } diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index 8041dc181bd4..e03fb9a1dbeb 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -509,7 +509,7 @@ void inet6_cleanup_sock(struct sock *sk) /* Free tx options */ - opt = xchg((__force struct ipv6_txoptions **)&np->opt, NULL); + opt = unrcu_pointer(xchg(&np->opt, NULL)); if (opt) { atomic_sub(opt->tot_len, &sk->sk_omem_alloc); txopt_put(opt); diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index 31d77885bcae..15f9abe50656 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -984,7 +984,7 @@ static void __fib6_drop_pcpu_from(struct fib6_nh *fib6_nh, if (pcpu_rt && rcu_access_pointer(pcpu_rt->from) == match) { struct fib6_info *from; - from = xchg((__force struct fib6_info **)&pcpu_rt->from, NULL); + from = unrcu_pointer(xchg(&pcpu_rt->from, NULL)); fib6_info_release(from); } } diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index d4c28ec1bc51..cd342d5015c6 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -111,8 +111,7 @@ struct ipv6_txoptions *ipv6_update_options(struct sock *sk, icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie); } } - opt = xchg((__force struct ipv6_txoptions **)&inet6_sk(sk)->opt, - opt); + opt = unrcu_pointer(xchg(&inet6_sk(sk)->opt, RCU_INITIALIZER(opt))); sk_dst_reset(sk); return opt; diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 12f647d0fec0..ae6fbdf8995d 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -368,7 +368,7 @@ static void ip6_dst_destroy(struct dst_entry *dst) in6_dev_put(idev); } - from = xchg((__force struct fib6_info **)&rt->from, NULL); + from = unrcu_pointer(xchg(&rt->from, NULL)); fib6_info_release(from); } @@ -1437,7 +1437,7 @@ static struct rt6_info *rt6_make_pcpu_route(struct net *net, if (res->f6i->fib6_destroying) { struct fib6_info *from; - from = xchg((__force struct fib6_info **)&pcpu_rt->from, NULL); + from = unrcu_pointer(xchg(&pcpu_rt->from, NULL)); fib6_info_release(from); } @@ -1466,7 +1466,7 @@ static void rt6_remove_exception(struct rt6_exception_bucket *bucket, /* purge completely the exception to allow releasing the held resources: * some [sk] cache may keep the dst around for unlimited time */ - from = xchg((__force struct fib6_info **)&rt6_ex->rt6i->from, NULL); + from = unrcu_pointer(xchg(&rt6_ex->rt6i->from, NULL)); fib6_info_release(from); dst_dev_put(&rt6_ex->rt6i->dst); diff --git a/net/sched/act_api.c b/net/sched/act_api.c index 9ee622fb1160..7458b3154426 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -62,7 +62,7 @@ static void tcf_set_action_cookie(struct tc_cookie __rcu **old_cookie, { struct tc_cookie *old; - old = xchg((__force struct tc_cookie **)old_cookie, new_cookie); + old = unrcu_pointer(xchg(old_cookie, RCU_INITIALIZER(new_cookie))); if (old) call_rcu(&old->rcu, tcf_free_cookie_rcu); } -- 2.25.1