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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /net/rds/tcp.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/rds/tcp.c')
-rw-r--r--net/rds/tcp.c754
1 files changed, 754 insertions, 0 deletions
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 <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/in.h>
+#include <linux/module.h>
+#include <net/tcp.h>
+#include <net/net_namespace.h>
+#include <net/netns/generic.h>
+#include <net/addrconf.h>
+
+#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 <rds-devel@oss.oracle.com>");
+MODULE_DESCRIPTION("RDS: TCP transport");
+MODULE_LICENSE("Dual BSD/GPL");