From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- net/rds/tcp.c | 754 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 754 insertions(+) create mode 100644 net/rds/tcp.c (limited to 'net/rds/tcp.c') diff --git a/net/rds/tcp.c b/net/rds/tcp.c new file mode 100644 index 000000000..4444fd82b --- /dev/null +++ b/net/rds/tcp.c @@ -0,0 +1,754 @@ +/* + * Copyright (c) 2006, 2018 Oracle and/or its affiliates. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include +#include +#include +#include +#include +#include +#include +#include + +#include "rds.h" +#include "tcp.h" + +/* only for info exporting */ +static DEFINE_SPINLOCK(rds_tcp_tc_list_lock); +static LIST_HEAD(rds_tcp_tc_list); + +/* rds_tcp_tc_count counts only IPv4 connections. + * rds6_tcp_tc_count counts both IPv4 and IPv6 connections. + */ +static unsigned int rds_tcp_tc_count; +#if IS_ENABLED(CONFIG_IPV6) +static unsigned int rds6_tcp_tc_count; +#endif + +/* Track rds_tcp_connection structs so they can be cleaned up */ +static DEFINE_SPINLOCK(rds_tcp_conn_lock); +static LIST_HEAD(rds_tcp_conn_list); +static atomic_t rds_tcp_unloading = ATOMIC_INIT(0); + +static struct kmem_cache *rds_tcp_conn_slab; + +static int rds_tcp_skbuf_handler(struct ctl_table *ctl, int write, + void *buffer, size_t *lenp, loff_t *fpos); + +static int rds_tcp_min_sndbuf = SOCK_MIN_SNDBUF; +static int rds_tcp_min_rcvbuf = SOCK_MIN_RCVBUF; + +static struct ctl_table rds_tcp_sysctl_table[] = { +#define RDS_TCP_SNDBUF 0 + { + .procname = "rds_tcp_sndbuf", + /* data is per-net pointer */ + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = rds_tcp_skbuf_handler, + .extra1 = &rds_tcp_min_sndbuf, + }, +#define RDS_TCP_RCVBUF 1 + { + .procname = "rds_tcp_rcvbuf", + /* data is per-net pointer */ + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = rds_tcp_skbuf_handler, + .extra1 = &rds_tcp_min_rcvbuf, + }, + { } +}; + +u32 rds_tcp_write_seq(struct rds_tcp_connection *tc) +{ + /* seq# of the last byte of data in tcp send buffer */ + return tcp_sk(tc->t_sock->sk)->write_seq; +} + +u32 rds_tcp_snd_una(struct rds_tcp_connection *tc) +{ + return tcp_sk(tc->t_sock->sk)->snd_una; +} + +void rds_tcp_restore_callbacks(struct socket *sock, + struct rds_tcp_connection *tc) +{ + rdsdebug("restoring sock %p callbacks from tc %p\n", sock, tc); + write_lock_bh(&sock->sk->sk_callback_lock); + + /* done under the callback_lock to serialize with write_space */ + spin_lock(&rds_tcp_tc_list_lock); + list_del_init(&tc->t_list_item); +#if IS_ENABLED(CONFIG_IPV6) + rds6_tcp_tc_count--; +#endif + if (!tc->t_cpath->cp_conn->c_isv6) + rds_tcp_tc_count--; + spin_unlock(&rds_tcp_tc_list_lock); + + tc->t_sock = NULL; + + sock->sk->sk_write_space = tc->t_orig_write_space; + sock->sk->sk_data_ready = tc->t_orig_data_ready; + sock->sk->sk_state_change = tc->t_orig_state_change; + sock->sk->sk_user_data = NULL; + + write_unlock_bh(&sock->sk->sk_callback_lock); +} + +/* + * rds_tcp_reset_callbacks() switches the to the new sock and + * returns the existing tc->t_sock. + * + * The only functions that set tc->t_sock are rds_tcp_set_callbacks + * and rds_tcp_reset_callbacks. Send and receive trust that + * it is set. The absence of RDS_CONN_UP bit protects those paths + * from being called while it isn't set. + */ +void rds_tcp_reset_callbacks(struct socket *sock, + struct rds_conn_path *cp) +{ + struct rds_tcp_connection *tc = cp->cp_transport_data; + struct socket *osock = tc->t_sock; + + if (!osock) + goto newsock; + + /* Need to resolve a duelling SYN between peers. + * We have an outstanding SYN to this peer, which may + * potentially have transitioned to the RDS_CONN_UP state, + * so we must quiesce any send threads before resetting + * cp_transport_data. We quiesce these threads by setting + * cp_state to something other than RDS_CONN_UP, and then + * waiting for any existing threads in rds_send_xmit to + * complete release_in_xmit(). (Subsequent threads entering + * rds_send_xmit() will bail on !rds_conn_up(). + * + * However an incoming syn-ack at this point would end up + * marking the conn as RDS_CONN_UP, and would again permit + * rds_send_xmi() threads through, so ideally we would + * synchronize on RDS_CONN_UP after lock_sock(), but cannot + * do that: waiting on !RDS_IN_XMIT after lock_sock() may + * end up deadlocking with tcp_sendmsg(), and the RDS_IN_XMIT + * would not get set. As a result, we set c_state to + * RDS_CONN_RESETTTING, to ensure that rds_tcp_state_change + * cannot mark rds_conn_path_up() in the window before lock_sock() + */ + atomic_set(&cp->cp_state, RDS_CONN_RESETTING); + wait_event(cp->cp_waitq, !test_bit(RDS_IN_XMIT, &cp->cp_flags)); + /* reset receive side state for rds_tcp_data_recv() for osock */ + cancel_delayed_work_sync(&cp->cp_send_w); + cancel_delayed_work_sync(&cp->cp_recv_w); + lock_sock(osock->sk); + if (tc->t_tinc) { + rds_inc_put(&tc->t_tinc->ti_inc); + tc->t_tinc = NULL; + } + tc->t_tinc_hdr_rem = sizeof(struct rds_header); + tc->t_tinc_data_rem = 0; + rds_tcp_restore_callbacks(osock, tc); + release_sock(osock->sk); + sock_release(osock); +newsock: + rds_send_path_reset(cp); + lock_sock(sock->sk); + rds_tcp_set_callbacks(sock, cp); + release_sock(sock->sk); +} + +/* Add tc to rds_tcp_tc_list and set tc->t_sock. See comments + * above rds_tcp_reset_callbacks for notes about synchronization + * with data path + */ +void rds_tcp_set_callbacks(struct socket *sock, struct rds_conn_path *cp) +{ + struct rds_tcp_connection *tc = cp->cp_transport_data; + + rdsdebug("setting sock %p callbacks to tc %p\n", sock, tc); + write_lock_bh(&sock->sk->sk_callback_lock); + + /* done under the callback_lock to serialize with write_space */ + spin_lock(&rds_tcp_tc_list_lock); + list_add_tail(&tc->t_list_item, &rds_tcp_tc_list); +#if IS_ENABLED(CONFIG_IPV6) + rds6_tcp_tc_count++; +#endif + if (!tc->t_cpath->cp_conn->c_isv6) + rds_tcp_tc_count++; + spin_unlock(&rds_tcp_tc_list_lock); + + /* accepted sockets need our listen data ready undone */ + if (sock->sk->sk_data_ready == rds_tcp_listen_data_ready) + sock->sk->sk_data_ready = sock->sk->sk_user_data; + + tc->t_sock = sock; + tc->t_cpath = cp; + tc->t_orig_data_ready = sock->sk->sk_data_ready; + tc->t_orig_write_space = sock->sk->sk_write_space; + tc->t_orig_state_change = sock->sk->sk_state_change; + + sock->sk->sk_user_data = cp; + sock->sk->sk_data_ready = rds_tcp_data_ready; + sock->sk->sk_write_space = rds_tcp_write_space; + sock->sk->sk_state_change = rds_tcp_state_change; + + write_unlock_bh(&sock->sk->sk_callback_lock); +} + +/* Handle RDS_INFO_TCP_SOCKETS socket option. It only returns IPv4 + * connections for backward compatibility. + */ +static void rds_tcp_tc_info(struct socket *rds_sock, unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens) +{ + struct rds_info_tcp_socket tsinfo; + struct rds_tcp_connection *tc; + unsigned long flags; + + spin_lock_irqsave(&rds_tcp_tc_list_lock, flags); + + if (len / sizeof(tsinfo) < rds_tcp_tc_count) + goto out; + + list_for_each_entry(tc, &rds_tcp_tc_list, t_list_item) { + struct inet_sock *inet = inet_sk(tc->t_sock->sk); + + if (tc->t_cpath->cp_conn->c_isv6) + continue; + + tsinfo.local_addr = inet->inet_saddr; + tsinfo.local_port = inet->inet_sport; + tsinfo.peer_addr = inet->inet_daddr; + tsinfo.peer_port = inet->inet_dport; + + tsinfo.hdr_rem = tc->t_tinc_hdr_rem; + tsinfo.data_rem = tc->t_tinc_data_rem; + tsinfo.last_sent_nxt = tc->t_last_sent_nxt; + tsinfo.last_expected_una = tc->t_last_expected_una; + tsinfo.last_seen_una = tc->t_last_seen_una; + tsinfo.tos = tc->t_cpath->cp_conn->c_tos; + + rds_info_copy(iter, &tsinfo, sizeof(tsinfo)); + } + +out: + lens->nr = rds_tcp_tc_count; + lens->each = sizeof(tsinfo); + + spin_unlock_irqrestore(&rds_tcp_tc_list_lock, flags); +} + +#if IS_ENABLED(CONFIG_IPV6) +/* Handle RDS6_INFO_TCP_SOCKETS socket option. It returns both IPv4 and + * IPv6 connections. IPv4 connection address is returned in an IPv4 mapped + * address. + */ +static void rds6_tcp_tc_info(struct socket *sock, unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens) +{ + struct rds6_info_tcp_socket tsinfo6; + struct rds_tcp_connection *tc; + unsigned long flags; + + spin_lock_irqsave(&rds_tcp_tc_list_lock, flags); + + if (len / sizeof(tsinfo6) < rds6_tcp_tc_count) + goto out; + + list_for_each_entry(tc, &rds_tcp_tc_list, t_list_item) { + struct sock *sk = tc->t_sock->sk; + struct inet_sock *inet = inet_sk(sk); + + tsinfo6.local_addr = sk->sk_v6_rcv_saddr; + tsinfo6.local_port = inet->inet_sport; + tsinfo6.peer_addr = sk->sk_v6_daddr; + tsinfo6.peer_port = inet->inet_dport; + + tsinfo6.hdr_rem = tc->t_tinc_hdr_rem; + tsinfo6.data_rem = tc->t_tinc_data_rem; + tsinfo6.last_sent_nxt = tc->t_last_sent_nxt; + tsinfo6.last_expected_una = tc->t_last_expected_una; + tsinfo6.last_seen_una = tc->t_last_seen_una; + + rds_info_copy(iter, &tsinfo6, sizeof(tsinfo6)); + } + +out: + lens->nr = rds6_tcp_tc_count; + lens->each = sizeof(tsinfo6); + + spin_unlock_irqrestore(&rds_tcp_tc_list_lock, flags); +} +#endif + +int rds_tcp_laddr_check(struct net *net, const struct in6_addr *addr, + __u32 scope_id) +{ + struct net_device *dev = NULL; +#if IS_ENABLED(CONFIG_IPV6) + int ret; +#endif + + if (ipv6_addr_v4mapped(addr)) { + if (inet_addr_type(net, addr->s6_addr32[3]) == RTN_LOCAL) + return 0; + return -EADDRNOTAVAIL; + } + + /* If the scope_id is specified, check only those addresses + * hosted on the specified interface. + */ + if (scope_id != 0) { + rcu_read_lock(); + dev = dev_get_by_index_rcu(net, scope_id); + /* scope_id is not valid... */ + if (!dev) { + rcu_read_unlock(); + return -EADDRNOTAVAIL; + } + rcu_read_unlock(); + } +#if IS_ENABLED(CONFIG_IPV6) + ret = ipv6_chk_addr(net, addr, dev, 0); + if (ret) + return 0; +#endif + return -EADDRNOTAVAIL; +} + +static void rds_tcp_conn_free(void *arg) +{ + struct rds_tcp_connection *tc = arg; + unsigned long flags; + + rdsdebug("freeing tc %p\n", tc); + + spin_lock_irqsave(&rds_tcp_conn_lock, flags); + if (!tc->t_tcp_node_detached) + list_del(&tc->t_tcp_node); + spin_unlock_irqrestore(&rds_tcp_conn_lock, flags); + + kmem_cache_free(rds_tcp_conn_slab, tc); +} + +static int rds_tcp_conn_alloc(struct rds_connection *conn, gfp_t gfp) +{ + struct rds_tcp_connection *tc; + int i, j; + int ret = 0; + + for (i = 0; i < RDS_MPATH_WORKERS; i++) { + tc = kmem_cache_alloc(rds_tcp_conn_slab, gfp); + if (!tc) { + ret = -ENOMEM; + goto fail; + } + mutex_init(&tc->t_conn_path_lock); + tc->t_sock = NULL; + tc->t_tinc = NULL; + tc->t_tinc_hdr_rem = sizeof(struct rds_header); + tc->t_tinc_data_rem = 0; + + conn->c_path[i].cp_transport_data = tc; + tc->t_cpath = &conn->c_path[i]; + tc->t_tcp_node_detached = true; + + rdsdebug("rds_conn_path [%d] tc %p\n", i, + conn->c_path[i].cp_transport_data); + } + spin_lock_irq(&rds_tcp_conn_lock); + for (i = 0; i < RDS_MPATH_WORKERS; i++) { + tc = conn->c_path[i].cp_transport_data; + tc->t_tcp_node_detached = false; + list_add_tail(&tc->t_tcp_node, &rds_tcp_conn_list); + } + spin_unlock_irq(&rds_tcp_conn_lock); +fail: + if (ret) { + for (j = 0; j < i; j++) + rds_tcp_conn_free(conn->c_path[j].cp_transport_data); + } + return ret; +} + +static bool list_has_conn(struct list_head *list, struct rds_connection *conn) +{ + struct rds_tcp_connection *tc, *_tc; + + list_for_each_entry_safe(tc, _tc, list, t_tcp_node) { + if (tc->t_cpath->cp_conn == conn) + return true; + } + return false; +} + +static void rds_tcp_set_unloading(void) +{ + atomic_set(&rds_tcp_unloading, 1); +} + +static bool rds_tcp_is_unloading(struct rds_connection *conn) +{ + return atomic_read(&rds_tcp_unloading) != 0; +} + +static void rds_tcp_destroy_conns(void) +{ + struct rds_tcp_connection *tc, *_tc; + LIST_HEAD(tmp_list); + + /* avoid calling conn_destroy with irqs off */ + spin_lock_irq(&rds_tcp_conn_lock); + list_for_each_entry_safe(tc, _tc, &rds_tcp_conn_list, t_tcp_node) { + if (!list_has_conn(&tmp_list, tc->t_cpath->cp_conn)) + list_move_tail(&tc->t_tcp_node, &tmp_list); + } + spin_unlock_irq(&rds_tcp_conn_lock); + + list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node) + rds_conn_destroy(tc->t_cpath->cp_conn); +} + +static void rds_tcp_exit(void); + +static u8 rds_tcp_get_tos_map(u8 tos) +{ + /* all user tos mapped to default 0 for TCP transport */ + return 0; +} + +struct rds_transport rds_tcp_transport = { + .laddr_check = rds_tcp_laddr_check, + .xmit_path_prepare = rds_tcp_xmit_path_prepare, + .xmit_path_complete = rds_tcp_xmit_path_complete, + .xmit = rds_tcp_xmit, + .recv_path = rds_tcp_recv_path, + .conn_alloc = rds_tcp_conn_alloc, + .conn_free = rds_tcp_conn_free, + .conn_path_connect = rds_tcp_conn_path_connect, + .conn_path_shutdown = rds_tcp_conn_path_shutdown, + .inc_copy_to_user = rds_tcp_inc_copy_to_user, + .inc_free = rds_tcp_inc_free, + .stats_info_copy = rds_tcp_stats_info_copy, + .exit = rds_tcp_exit, + .get_tos_map = rds_tcp_get_tos_map, + .t_owner = THIS_MODULE, + .t_name = "tcp", + .t_type = RDS_TRANS_TCP, + .t_prefer_loopback = 1, + .t_mp_capable = 1, + .t_unloading = rds_tcp_is_unloading, +}; + +static unsigned int rds_tcp_netid; + +/* per-network namespace private data for this module */ +struct rds_tcp_net { + struct socket *rds_tcp_listen_sock; + struct work_struct rds_tcp_accept_w; + struct ctl_table_header *rds_tcp_sysctl; + struct ctl_table *ctl_table; + int sndbuf_size; + int rcvbuf_size; +}; + +/* All module specific customizations to the RDS-TCP socket should be done in + * rds_tcp_tune() and applied after socket creation. + */ +bool rds_tcp_tune(struct socket *sock) +{ + struct sock *sk = sock->sk; + struct net *net = sock_net(sk); + struct rds_tcp_net *rtn; + + tcp_sock_set_nodelay(sock->sk); + lock_sock(sk); + /* TCP timer functions might access net namespace even after + * a process which created this net namespace terminated. + */ + if (!sk->sk_net_refcnt) { + if (!maybe_get_net(net)) { + release_sock(sk); + return false; + } + sk->sk_net_refcnt = 1; + netns_tracker_alloc(net, &sk->ns_tracker, GFP_KERNEL); + sock_inuse_add(net, 1); + } + rtn = net_generic(net, rds_tcp_netid); + if (rtn->sndbuf_size > 0) { + sk->sk_sndbuf = rtn->sndbuf_size; + sk->sk_userlocks |= SOCK_SNDBUF_LOCK; + } + if (rtn->rcvbuf_size > 0) { + sk->sk_rcvbuf = rtn->rcvbuf_size; + sk->sk_userlocks |= SOCK_RCVBUF_LOCK; + } + release_sock(sk); + return true; +} + +static void rds_tcp_accept_worker(struct work_struct *work) +{ + struct rds_tcp_net *rtn = container_of(work, + struct rds_tcp_net, + rds_tcp_accept_w); + + while (rds_tcp_accept_one(rtn->rds_tcp_listen_sock) == 0) + cond_resched(); +} + +void rds_tcp_accept_work(struct sock *sk) +{ + struct net *net = sock_net(sk); + struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid); + + queue_work(rds_wq, &rtn->rds_tcp_accept_w); +} + +static __net_init int rds_tcp_init_net(struct net *net) +{ + struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid); + struct ctl_table *tbl; + int err = 0; + + memset(rtn, 0, sizeof(*rtn)); + + /* {snd, rcv}buf_size default to 0, which implies we let the + * stack pick the value, and permit auto-tuning of buffer size. + */ + if (net == &init_net) { + tbl = rds_tcp_sysctl_table; + } else { + tbl = kmemdup(rds_tcp_sysctl_table, + sizeof(rds_tcp_sysctl_table), GFP_KERNEL); + if (!tbl) { + pr_warn("could not set allocate sysctl table\n"); + return -ENOMEM; + } + rtn->ctl_table = tbl; + } + tbl[RDS_TCP_SNDBUF].data = &rtn->sndbuf_size; + tbl[RDS_TCP_RCVBUF].data = &rtn->rcvbuf_size; + rtn->rds_tcp_sysctl = register_net_sysctl(net, "net/rds/tcp", tbl); + if (!rtn->rds_tcp_sysctl) { + pr_warn("could not register sysctl\n"); + err = -ENOMEM; + goto fail; + } + +#if IS_ENABLED(CONFIG_IPV6) + rtn->rds_tcp_listen_sock = rds_tcp_listen_init(net, true); +#else + rtn->rds_tcp_listen_sock = rds_tcp_listen_init(net, false); +#endif + if (!rtn->rds_tcp_listen_sock) { + pr_warn("could not set up IPv6 listen sock\n"); + +#if IS_ENABLED(CONFIG_IPV6) + /* Try IPv4 as some systems disable IPv6 */ + rtn->rds_tcp_listen_sock = rds_tcp_listen_init(net, false); + if (!rtn->rds_tcp_listen_sock) { +#endif + unregister_net_sysctl_table(rtn->rds_tcp_sysctl); + rtn->rds_tcp_sysctl = NULL; + err = -EAFNOSUPPORT; + goto fail; +#if IS_ENABLED(CONFIG_IPV6) + } +#endif + } + INIT_WORK(&rtn->rds_tcp_accept_w, rds_tcp_accept_worker); + return 0; + +fail: + if (net != &init_net) + kfree(tbl); + return err; +} + +static void rds_tcp_kill_sock(struct net *net) +{ + struct rds_tcp_connection *tc, *_tc; + LIST_HEAD(tmp_list); + struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid); + struct socket *lsock = rtn->rds_tcp_listen_sock; + + rtn->rds_tcp_listen_sock = NULL; + rds_tcp_listen_stop(lsock, &rtn->rds_tcp_accept_w); + spin_lock_irq(&rds_tcp_conn_lock); + list_for_each_entry_safe(tc, _tc, &rds_tcp_conn_list, t_tcp_node) { + struct net *c_net = read_pnet(&tc->t_cpath->cp_conn->c_net); + + if (net != c_net) + continue; + if (!list_has_conn(&tmp_list, tc->t_cpath->cp_conn)) { + list_move_tail(&tc->t_tcp_node, &tmp_list); + } else { + list_del(&tc->t_tcp_node); + tc->t_tcp_node_detached = true; + } + } + spin_unlock_irq(&rds_tcp_conn_lock); + list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node) + rds_conn_destroy(tc->t_cpath->cp_conn); +} + +static void __net_exit rds_tcp_exit_net(struct net *net) +{ + struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid); + + rds_tcp_kill_sock(net); + + if (rtn->rds_tcp_sysctl) + unregister_net_sysctl_table(rtn->rds_tcp_sysctl); + + if (net != &init_net) + kfree(rtn->ctl_table); +} + +static struct pernet_operations rds_tcp_net_ops = { + .init = rds_tcp_init_net, + .exit = rds_tcp_exit_net, + .id = &rds_tcp_netid, + .size = sizeof(struct rds_tcp_net), +}; + +void *rds_tcp_listen_sock_def_readable(struct net *net) +{ + struct rds_tcp_net *rtn = net_generic(net, rds_tcp_netid); + struct socket *lsock = rtn->rds_tcp_listen_sock; + + if (!lsock) + return NULL; + + return lsock->sk->sk_user_data; +} + +/* when sysctl is used to modify some kernel socket parameters,this + * function resets the RDS connections in that netns so that we can + * restart with new parameters. The assumption is that such reset + * events are few and far-between. + */ +static void rds_tcp_sysctl_reset(struct net *net) +{ + struct rds_tcp_connection *tc, *_tc; + + spin_lock_irq(&rds_tcp_conn_lock); + list_for_each_entry_safe(tc, _tc, &rds_tcp_conn_list, t_tcp_node) { + struct net *c_net = read_pnet(&tc->t_cpath->cp_conn->c_net); + + if (net != c_net || !tc->t_sock) + continue; + + /* reconnect with new parameters */ + rds_conn_path_drop(tc->t_cpath, false); + } + spin_unlock_irq(&rds_tcp_conn_lock); +} + +static int rds_tcp_skbuf_handler(struct ctl_table *ctl, int write, + void *buffer, size_t *lenp, loff_t *fpos) +{ + struct net *net = current->nsproxy->net_ns; + int err; + + err = proc_dointvec_minmax(ctl, write, buffer, lenp, fpos); + if (err < 0) { + pr_warn("Invalid input. Must be >= %d\n", + *(int *)(ctl->extra1)); + return err; + } + if (write) + rds_tcp_sysctl_reset(net); + return 0; +} + +static void rds_tcp_exit(void) +{ + rds_tcp_set_unloading(); + synchronize_rcu(); + rds_info_deregister_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info); +#if IS_ENABLED(CONFIG_IPV6) + rds_info_deregister_func(RDS6_INFO_TCP_SOCKETS, rds6_tcp_tc_info); +#endif + unregister_pernet_device(&rds_tcp_net_ops); + rds_tcp_destroy_conns(); + rds_trans_unregister(&rds_tcp_transport); + rds_tcp_recv_exit(); + kmem_cache_destroy(rds_tcp_conn_slab); +} +module_exit(rds_tcp_exit); + +static int __init rds_tcp_init(void) +{ + int ret; + + rds_tcp_conn_slab = kmem_cache_create("rds_tcp_connection", + sizeof(struct rds_tcp_connection), + 0, 0, NULL); + if (!rds_tcp_conn_slab) { + ret = -ENOMEM; + goto out; + } + + ret = rds_tcp_recv_init(); + if (ret) + goto out_slab; + + ret = register_pernet_device(&rds_tcp_net_ops); + if (ret) + goto out_recv; + + rds_trans_register(&rds_tcp_transport); + + rds_info_register_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info); +#if IS_ENABLED(CONFIG_IPV6) + rds_info_register_func(RDS6_INFO_TCP_SOCKETS, rds6_tcp_tc_info); +#endif + + goto out; +out_recv: + rds_tcp_recv_exit(); +out_slab: + kmem_cache_destroy(rds_tcp_conn_slab); +out: + return ret; +} +module_init(rds_tcp_init); + +MODULE_AUTHOR("Oracle Corporation "); +MODULE_DESCRIPTION("RDS: TCP transport"); +MODULE_LICENSE("Dual BSD/GPL"); -- cgit v1.2.3