diff options
Diffstat (limited to '')
| -rw-r--r-- | net/rds/connection.c | 948 |
1 files changed, 948 insertions, 0 deletions
diff --git a/net/rds/connection.c b/net/rds/connection.c new file mode 100644 index 000000000..b4cc699c5 --- /dev/null +++ b/net/rds/connection.c @@ -0,0 +1,948 @@ +/* + * 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/list.h> +#include <linux/slab.h> +#include <linux/export.h> +#include <net/ipv6.h> +#include <net/inet6_hashtables.h> +#include <net/addrconf.h> + +#include "rds.h" +#include "loop.h" + +#define RDS_CONNECTION_HASH_BITS 12 +#define RDS_CONNECTION_HASH_ENTRIES (1 << RDS_CONNECTION_HASH_BITS) +#define RDS_CONNECTION_HASH_MASK (RDS_CONNECTION_HASH_ENTRIES - 1) + +/* converting this to RCU is a chore for another day.. */ +static DEFINE_SPINLOCK(rds_conn_lock); +static unsigned long rds_conn_count; +static struct hlist_head rds_conn_hash[RDS_CONNECTION_HASH_ENTRIES]; +static struct kmem_cache *rds_conn_slab; + +static struct hlist_head *rds_conn_bucket(const struct in6_addr *laddr, + const struct in6_addr *faddr) +{ + static u32 rds6_hash_secret __read_mostly; + static u32 rds_hash_secret __read_mostly; + + u32 lhash, fhash, hash; + + net_get_random_once(&rds_hash_secret, sizeof(rds_hash_secret)); + net_get_random_once(&rds6_hash_secret, sizeof(rds6_hash_secret)); + + lhash = (__force u32)laddr->s6_addr32[3]; +#if IS_ENABLED(CONFIG_IPV6) + fhash = __ipv6_addr_jhash(faddr, rds6_hash_secret); +#else + fhash = (__force u32)faddr->s6_addr32[3]; +#endif + hash = __inet_ehashfn(lhash, 0, fhash, 0, rds_hash_secret); + + return &rds_conn_hash[hash & RDS_CONNECTION_HASH_MASK]; +} + +#define rds_conn_info_set(var, test, suffix) do { \ + if (test) \ + var |= RDS_INFO_CONNECTION_FLAG_##suffix; \ +} while (0) + +/* rcu read lock must be held or the connection spinlock */ +static struct rds_connection *rds_conn_lookup(struct net *net, + struct hlist_head *head, + const struct in6_addr *laddr, + const struct in6_addr *faddr, + struct rds_transport *trans, + u8 tos, int dev_if) +{ + struct rds_connection *conn, *ret = NULL; + + hlist_for_each_entry_rcu(conn, head, c_hash_node) { + if (ipv6_addr_equal(&conn->c_faddr, faddr) && + ipv6_addr_equal(&conn->c_laddr, laddr) && + conn->c_trans == trans && + conn->c_tos == tos && + net == rds_conn_net(conn) && + conn->c_dev_if == dev_if) { + ret = conn; + break; + } + } + rdsdebug("returning conn %p for %pI6c -> %pI6c\n", ret, + laddr, faddr); + return ret; +} + +/* + * This is called by transports as they're bringing down a connection. + * It clears partial message state so that the transport can start sending + * and receiving over this connection again in the future. It is up to + * the transport to have serialized this call with its send and recv. + */ +static void rds_conn_path_reset(struct rds_conn_path *cp) +{ + struct rds_connection *conn = cp->cp_conn; + + rdsdebug("connection %pI6c to %pI6c reset\n", + &conn->c_laddr, &conn->c_faddr); + + rds_stats_inc(s_conn_reset); + rds_send_path_reset(cp); + cp->cp_flags = 0; + + /* Do not clear next_rx_seq here, else we cannot distinguish + * retransmitted packets from new packets, and will hand all + * of them to the application. That is not consistent with the + * reliability guarantees of RDS. */ +} + +static void __rds_conn_path_init(struct rds_connection *conn, + struct rds_conn_path *cp, bool is_outgoing) +{ + spin_lock_init(&cp->cp_lock); + cp->cp_next_tx_seq = 1; + init_waitqueue_head(&cp->cp_waitq); + INIT_LIST_HEAD(&cp->cp_send_queue); + INIT_LIST_HEAD(&cp->cp_retrans); + + cp->cp_conn = conn; + atomic_set(&cp->cp_state, RDS_CONN_DOWN); + cp->cp_send_gen = 0; + cp->cp_reconnect_jiffies = 0; + cp->cp_conn->c_proposed_version = RDS_PROTOCOL_VERSION; + INIT_DELAYED_WORK(&cp->cp_send_w, rds_send_worker); + INIT_DELAYED_WORK(&cp->cp_recv_w, rds_recv_worker); + INIT_DELAYED_WORK(&cp->cp_conn_w, rds_connect_worker); + INIT_WORK(&cp->cp_down_w, rds_shutdown_worker); + mutex_init(&cp->cp_cm_lock); + cp->cp_flags = 0; +} + +/* + * There is only every one 'conn' for a given pair of addresses in the + * system at a time. They contain messages to be retransmitted and so + * span the lifetime of the actual underlying transport connections. + * + * For now they are not garbage collected once they're created. They + * are torn down as the module is removed, if ever. + */ +static struct rds_connection *__rds_conn_create(struct net *net, + const struct in6_addr *laddr, + const struct in6_addr *faddr, + struct rds_transport *trans, + gfp_t gfp, u8 tos, + int is_outgoing, + int dev_if) +{ + struct rds_connection *conn, *parent = NULL; + struct hlist_head *head = rds_conn_bucket(laddr, faddr); + struct rds_transport *loop_trans; + unsigned long flags; + int ret, i; + int npaths = (trans->t_mp_capable ? RDS_MPATH_WORKERS : 1); + + rcu_read_lock(); + conn = rds_conn_lookup(net, head, laddr, faddr, trans, tos, dev_if); + if (conn && + conn->c_loopback && + conn->c_trans != &rds_loop_transport && + ipv6_addr_equal(laddr, faddr) && + !is_outgoing) { + /* This is a looped back IB connection, and we're + * called by the code handling the incoming connect. + * We need a second connection object into which we + * can stick the other QP. */ + parent = conn; + conn = parent->c_passive; + } + rcu_read_unlock(); + if (conn) + goto out; + + conn = kmem_cache_zalloc(rds_conn_slab, gfp); + if (!conn) { + conn = ERR_PTR(-ENOMEM); + goto out; + } + conn->c_path = kcalloc(npaths, sizeof(struct rds_conn_path), gfp); + if (!conn->c_path) { + kmem_cache_free(rds_conn_slab, conn); + conn = ERR_PTR(-ENOMEM); + goto out; + } + + INIT_HLIST_NODE(&conn->c_hash_node); + conn->c_laddr = *laddr; + conn->c_isv6 = !ipv6_addr_v4mapped(laddr); + conn->c_faddr = *faddr; + conn->c_dev_if = dev_if; + conn->c_tos = tos; + +#if IS_ENABLED(CONFIG_IPV6) + /* If the local address is link local, set c_bound_if to be the + * index used for this connection. Otherwise, set it to 0 as + * the socket is not bound to an interface. c_bound_if is used + * to look up a socket when a packet is received + */ + if (ipv6_addr_type(laddr) & IPV6_ADDR_LINKLOCAL) + conn->c_bound_if = dev_if; + else +#endif + conn->c_bound_if = 0; + + rds_conn_net_set(conn, net); + + ret = rds_cong_get_maps(conn); + if (ret) { + kfree(conn->c_path); + kmem_cache_free(rds_conn_slab, conn); + conn = ERR_PTR(ret); + goto out; + } + + /* + * This is where a connection becomes loopback. If *any* RDS sockets + * can bind to the destination address then we'd rather the messages + * flow through loopback rather than either transport. + */ + loop_trans = rds_trans_get_preferred(net, faddr, conn->c_dev_if); + if (loop_trans) { + rds_trans_put(loop_trans); + conn->c_loopback = 1; + if (trans->t_prefer_loopback) { + if (likely(is_outgoing)) { + /* "outgoing" connection to local address. + * Protocol says it wants the connection + * handled by the loopback transport. + * This is what TCP does. + */ + trans = &rds_loop_transport; + } else { + /* No transport currently in use + * should end up here, but if it + * does, reset/destroy the connection. + */ + kfree(conn->c_path); + kmem_cache_free(rds_conn_slab, conn); + conn = ERR_PTR(-EOPNOTSUPP); + goto out; + } + } + } + + conn->c_trans = trans; + + init_waitqueue_head(&conn->c_hs_waitq); + for (i = 0; i < npaths; i++) { + __rds_conn_path_init(conn, &conn->c_path[i], + is_outgoing); + conn->c_path[i].cp_index = i; + } + rcu_read_lock(); + if (rds_destroy_pending(conn)) + ret = -ENETDOWN; + else + ret = trans->conn_alloc(conn, GFP_ATOMIC); + if (ret) { + rcu_read_unlock(); + kfree(conn->c_path); + kmem_cache_free(rds_conn_slab, conn); + conn = ERR_PTR(ret); + goto out; + } + + rdsdebug("allocated conn %p for %pI6c -> %pI6c over %s %s\n", + conn, laddr, faddr, + strnlen(trans->t_name, sizeof(trans->t_name)) ? + trans->t_name : "[unknown]", is_outgoing ? "(outgoing)" : ""); + + /* + * Since we ran without holding the conn lock, someone could + * have created the same conn (either normal or passive) in the + * interim. We check while holding the lock. If we won, we complete + * init and return our conn. If we lost, we rollback and return the + * other one. + */ + spin_lock_irqsave(&rds_conn_lock, flags); + if (parent) { + /* Creating passive conn */ + if (parent->c_passive) { + trans->conn_free(conn->c_path[0].cp_transport_data); + kfree(conn->c_path); + kmem_cache_free(rds_conn_slab, conn); + conn = parent->c_passive; + } else { + parent->c_passive = conn; + rds_cong_add_conn(conn); + rds_conn_count++; + } + } else { + /* Creating normal conn */ + struct rds_connection *found; + + found = rds_conn_lookup(net, head, laddr, faddr, trans, + tos, dev_if); + if (found) { + struct rds_conn_path *cp; + int i; + + for (i = 0; i < npaths; i++) { + cp = &conn->c_path[i]; + /* The ->conn_alloc invocation may have + * allocated resource for all paths, so all + * of them may have to be freed here. + */ + if (cp->cp_transport_data) + trans->conn_free(cp->cp_transport_data); + } + kfree(conn->c_path); + kmem_cache_free(rds_conn_slab, conn); + conn = found; + } else { + conn->c_my_gen_num = rds_gen_num; + conn->c_peer_gen_num = 0; + hlist_add_head_rcu(&conn->c_hash_node, head); + rds_cong_add_conn(conn); + rds_conn_count++; + } + } + spin_unlock_irqrestore(&rds_conn_lock, flags); + rcu_read_unlock(); + +out: + return conn; +} + +struct rds_connection *rds_conn_create(struct net *net, + const struct in6_addr *laddr, + const struct in6_addr *faddr, + struct rds_transport *trans, u8 tos, + gfp_t gfp, int dev_if) +{ + return __rds_conn_create(net, laddr, faddr, trans, gfp, tos, 0, dev_if); +} +EXPORT_SYMBOL_GPL(rds_conn_create); + +struct rds_connection *rds_conn_create_outgoing(struct net *net, + const struct in6_addr *laddr, + const struct in6_addr *faddr, + struct rds_transport *trans, + u8 tos, gfp_t gfp, int dev_if) +{ + return __rds_conn_create(net, laddr, faddr, trans, gfp, tos, 1, dev_if); +} +EXPORT_SYMBOL_GPL(rds_conn_create_outgoing); + +void rds_conn_shutdown(struct rds_conn_path *cp) +{ + struct rds_connection *conn = cp->cp_conn; + + /* shut it down unless it's down already */ + if (!rds_conn_path_transition(cp, RDS_CONN_DOWN, RDS_CONN_DOWN)) { + /* + * Quiesce the connection mgmt handlers before we start tearing + * things down. We don't hold the mutex for the entire + * duration of the shutdown operation, else we may be + * deadlocking with the CM handler. Instead, the CM event + * handler is supposed to check for state DISCONNECTING + */ + mutex_lock(&cp->cp_cm_lock); + if (!rds_conn_path_transition(cp, RDS_CONN_UP, + RDS_CONN_DISCONNECTING) && + !rds_conn_path_transition(cp, RDS_CONN_ERROR, + RDS_CONN_DISCONNECTING)) { + rds_conn_path_error(cp, + "shutdown called in state %d\n", + atomic_read(&cp->cp_state)); + mutex_unlock(&cp->cp_cm_lock); + return; + } + mutex_unlock(&cp->cp_cm_lock); + + wait_event(cp->cp_waitq, + !test_bit(RDS_IN_XMIT, &cp->cp_flags)); + wait_event(cp->cp_waitq, + !test_bit(RDS_RECV_REFILL, &cp->cp_flags)); + + conn->c_trans->conn_path_shutdown(cp); + rds_conn_path_reset(cp); + + if (!rds_conn_path_transition(cp, RDS_CONN_DISCONNECTING, + RDS_CONN_DOWN) && + !rds_conn_path_transition(cp, RDS_CONN_ERROR, + RDS_CONN_DOWN)) { + /* This can happen - eg when we're in the middle of tearing + * down the connection, and someone unloads the rds module. + * Quite reproducible with loopback connections. + * Mostly harmless. + * + * Note that this also happens with rds-tcp because + * we could have triggered rds_conn_path_drop in irq + * mode from rds_tcp_state change on the receipt of + * a FIN, thus we need to recheck for RDS_CONN_ERROR + * here. + */ + rds_conn_path_error(cp, "%s: failed to transition " + "to state DOWN, current state " + "is %d\n", __func__, + atomic_read(&cp->cp_state)); + return; + } + } + + /* Then reconnect if it's still live. + * The passive side of an IB loopback connection is never added + * to the conn hash, so we never trigger a reconnect on this + * conn - the reconnect is always triggered by the active peer. */ + cancel_delayed_work_sync(&cp->cp_conn_w); + rcu_read_lock(); + if (!hlist_unhashed(&conn->c_hash_node)) { + rcu_read_unlock(); + rds_queue_reconnect(cp); + } else { + rcu_read_unlock(); + } +} + +/* destroy a single rds_conn_path. rds_conn_destroy() iterates over + * all paths using rds_conn_path_destroy() + */ +static void rds_conn_path_destroy(struct rds_conn_path *cp) +{ + struct rds_message *rm, *rtmp; + + if (!cp->cp_transport_data) + return; + + /* make sure lingering queued work won't try to ref the conn */ + cancel_delayed_work_sync(&cp->cp_send_w); + cancel_delayed_work_sync(&cp->cp_recv_w); + + rds_conn_path_drop(cp, true); + flush_work(&cp->cp_down_w); + + /* tear down queued messages */ + list_for_each_entry_safe(rm, rtmp, + &cp->cp_send_queue, + m_conn_item) { + list_del_init(&rm->m_conn_item); + BUG_ON(!list_empty(&rm->m_sock_item)); + rds_message_put(rm); + } + if (cp->cp_xmit_rm) + rds_message_put(cp->cp_xmit_rm); + + WARN_ON(delayed_work_pending(&cp->cp_send_w)); + WARN_ON(delayed_work_pending(&cp->cp_recv_w)); + WARN_ON(delayed_work_pending(&cp->cp_conn_w)); + WARN_ON(work_pending(&cp->cp_down_w)); + + cp->cp_conn->c_trans->conn_free(cp->cp_transport_data); +} + +/* + * Stop and free a connection. + * + * This can only be used in very limited circumstances. It assumes that once + * the conn has been shutdown that no one else is referencing the connection. + * We can only ensure this in the rmmod path in the current code. + */ +void rds_conn_destroy(struct rds_connection *conn) +{ + unsigned long flags; + int i; + struct rds_conn_path *cp; + int npaths = (conn->c_trans->t_mp_capable ? RDS_MPATH_WORKERS : 1); + + rdsdebug("freeing conn %p for %pI4 -> " + "%pI4\n", conn, &conn->c_laddr, + &conn->c_faddr); + + /* Ensure conn will not be scheduled for reconnect */ + spin_lock_irq(&rds_conn_lock); + hlist_del_init_rcu(&conn->c_hash_node); + spin_unlock_irq(&rds_conn_lock); + synchronize_rcu(); + + /* shut the connection down */ + for (i = 0; i < npaths; i++) { + cp = &conn->c_path[i]; + rds_conn_path_destroy(cp); + BUG_ON(!list_empty(&cp->cp_retrans)); + } + + /* + * The congestion maps aren't freed up here. They're + * freed by rds_cong_exit() after all the connections + * have been freed. + */ + rds_cong_remove_conn(conn); + + kfree(conn->c_path); + kmem_cache_free(rds_conn_slab, conn); + + spin_lock_irqsave(&rds_conn_lock, flags); + rds_conn_count--; + spin_unlock_irqrestore(&rds_conn_lock, flags); +} +EXPORT_SYMBOL_GPL(rds_conn_destroy); + +static void __rds_inc_msg_cp(struct rds_incoming *inc, + struct rds_info_iterator *iter, + void *saddr, void *daddr, int flip, bool isv6) +{ +#if IS_ENABLED(CONFIG_IPV6) + if (isv6) + rds6_inc_info_copy(inc, iter, saddr, daddr, flip); + else +#endif + rds_inc_info_copy(inc, iter, *(__be32 *)saddr, + *(__be32 *)daddr, flip); +} + +static void rds_conn_message_info_cmn(struct socket *sock, unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens, + int want_send, bool isv6) +{ + struct hlist_head *head; + struct list_head *list; + struct rds_connection *conn; + struct rds_message *rm; + unsigned int total = 0; + unsigned long flags; + size_t i; + int j; + + if (isv6) + len /= sizeof(struct rds6_info_message); + else + len /= sizeof(struct rds_info_message); + + rcu_read_lock(); + + for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash); + i++, head++) { + hlist_for_each_entry_rcu(conn, head, c_hash_node) { + struct rds_conn_path *cp; + int npaths; + + if (!isv6 && conn->c_isv6) + continue; + + npaths = (conn->c_trans->t_mp_capable ? + RDS_MPATH_WORKERS : 1); + + for (j = 0; j < npaths; j++) { + cp = &conn->c_path[j]; + if (want_send) + list = &cp->cp_send_queue; + else + list = &cp->cp_retrans; + + spin_lock_irqsave(&cp->cp_lock, flags); + + /* XXX too lazy to maintain counts.. */ + list_for_each_entry(rm, list, m_conn_item) { + total++; + if (total <= len) + __rds_inc_msg_cp(&rm->m_inc, + iter, + &conn->c_laddr, + &conn->c_faddr, + 0, isv6); + } + + spin_unlock_irqrestore(&cp->cp_lock, flags); + } + } + } + rcu_read_unlock(); + + lens->nr = total; + if (isv6) + lens->each = sizeof(struct rds6_info_message); + else + lens->each = sizeof(struct rds_info_message); +} + +static void rds_conn_message_info(struct socket *sock, unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens, + int want_send) +{ + rds_conn_message_info_cmn(sock, len, iter, lens, want_send, false); +} + +#if IS_ENABLED(CONFIG_IPV6) +static void rds6_conn_message_info(struct socket *sock, unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens, + int want_send) +{ + rds_conn_message_info_cmn(sock, len, iter, lens, want_send, true); +} +#endif + +static void rds_conn_message_info_send(struct socket *sock, unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens) +{ + rds_conn_message_info(sock, len, iter, lens, 1); +} + +#if IS_ENABLED(CONFIG_IPV6) +static void rds6_conn_message_info_send(struct socket *sock, unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens) +{ + rds6_conn_message_info(sock, len, iter, lens, 1); +} +#endif + +static void rds_conn_message_info_retrans(struct socket *sock, + unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens) +{ + rds_conn_message_info(sock, len, iter, lens, 0); +} + +#if IS_ENABLED(CONFIG_IPV6) +static void rds6_conn_message_info_retrans(struct socket *sock, + unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens) +{ + rds6_conn_message_info(sock, len, iter, lens, 0); +} +#endif + +void rds_for_each_conn_info(struct socket *sock, unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens, + int (*visitor)(struct rds_connection *, void *), + u64 *buffer, + size_t item_len) +{ + struct hlist_head *head; + struct rds_connection *conn; + size_t i; + + rcu_read_lock(); + + lens->nr = 0; + lens->each = item_len; + + for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash); + i++, head++) { + hlist_for_each_entry_rcu(conn, head, c_hash_node) { + + /* XXX no c_lock usage.. */ + if (!visitor(conn, buffer)) + continue; + + /* We copy as much as we can fit in the buffer, + * but we count all items so that the caller + * can resize the buffer. */ + if (len >= item_len) { + rds_info_copy(iter, buffer, item_len); + len -= item_len; + } + lens->nr++; + } + } + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(rds_for_each_conn_info); + +static void rds_walk_conn_path_info(struct socket *sock, unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens, + int (*visitor)(struct rds_conn_path *, void *), + u64 *buffer, + size_t item_len) +{ + struct hlist_head *head; + struct rds_connection *conn; + size_t i; + + rcu_read_lock(); + + lens->nr = 0; + lens->each = item_len; + + for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash); + i++, head++) { + hlist_for_each_entry_rcu(conn, head, c_hash_node) { + struct rds_conn_path *cp; + + /* XXX We only copy the information from the first + * path for now. The problem is that if there are + * more than one underlying paths, we cannot report + * information of all of them using the existing + * API. For example, there is only one next_tx_seq, + * which path's next_tx_seq should we report? It is + * a bug in the design of MPRDS. + */ + cp = conn->c_path; + + /* XXX no cp_lock usage.. */ + if (!visitor(cp, buffer)) + continue; + + /* We copy as much as we can fit in the buffer, + * but we count all items so that the caller + * can resize the buffer. + */ + if (len >= item_len) { + rds_info_copy(iter, buffer, item_len); + len -= item_len; + } + lens->nr++; + } + } + rcu_read_unlock(); +} + +static int rds_conn_info_visitor(struct rds_conn_path *cp, void *buffer) +{ + struct rds_info_connection *cinfo = buffer; + struct rds_connection *conn = cp->cp_conn; + + if (conn->c_isv6) + return 0; + + cinfo->next_tx_seq = cp->cp_next_tx_seq; + cinfo->next_rx_seq = cp->cp_next_rx_seq; + cinfo->laddr = conn->c_laddr.s6_addr32[3]; + cinfo->faddr = conn->c_faddr.s6_addr32[3]; + cinfo->tos = conn->c_tos; + strncpy(cinfo->transport, conn->c_trans->t_name, + sizeof(cinfo->transport)); + cinfo->flags = 0; + + rds_conn_info_set(cinfo->flags, test_bit(RDS_IN_XMIT, &cp->cp_flags), + SENDING); + /* XXX Future: return the state rather than these funky bits */ + rds_conn_info_set(cinfo->flags, + atomic_read(&cp->cp_state) == RDS_CONN_CONNECTING, + CONNECTING); + rds_conn_info_set(cinfo->flags, + atomic_read(&cp->cp_state) == RDS_CONN_UP, + CONNECTED); + return 1; +} + +#if IS_ENABLED(CONFIG_IPV6) +static int rds6_conn_info_visitor(struct rds_conn_path *cp, void *buffer) +{ + struct rds6_info_connection *cinfo6 = buffer; + struct rds_connection *conn = cp->cp_conn; + + cinfo6->next_tx_seq = cp->cp_next_tx_seq; + cinfo6->next_rx_seq = cp->cp_next_rx_seq; + cinfo6->laddr = conn->c_laddr; + cinfo6->faddr = conn->c_faddr; + strncpy(cinfo6->transport, conn->c_trans->t_name, + sizeof(cinfo6->transport)); + cinfo6->flags = 0; + + rds_conn_info_set(cinfo6->flags, test_bit(RDS_IN_XMIT, &cp->cp_flags), + SENDING); + /* XXX Future: return the state rather than these funky bits */ + rds_conn_info_set(cinfo6->flags, + atomic_read(&cp->cp_state) == RDS_CONN_CONNECTING, + CONNECTING); + rds_conn_info_set(cinfo6->flags, + atomic_read(&cp->cp_state) == RDS_CONN_UP, + CONNECTED); + /* Just return 1 as there is no error case. This is a helper function + * for rds_walk_conn_path_info() and it wants a return value. + */ + return 1; +} +#endif + +static void rds_conn_info(struct socket *sock, unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens) +{ + u64 buffer[(sizeof(struct rds_info_connection) + 7) / 8]; + + rds_walk_conn_path_info(sock, len, iter, lens, + rds_conn_info_visitor, + buffer, + sizeof(struct rds_info_connection)); +} + +#if IS_ENABLED(CONFIG_IPV6) +static void rds6_conn_info(struct socket *sock, unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens) +{ + u64 buffer[(sizeof(struct rds6_info_connection) + 7) / 8]; + + rds_walk_conn_path_info(sock, len, iter, lens, + rds6_conn_info_visitor, + buffer, + sizeof(struct rds6_info_connection)); +} +#endif + +int rds_conn_init(void) +{ + int ret; + + ret = rds_loop_net_init(); /* register pernet callback */ + if (ret) + return ret; + + rds_conn_slab = kmem_cache_create("rds_connection", + sizeof(struct rds_connection), + 0, 0, NULL); + if (!rds_conn_slab) { + rds_loop_net_exit(); + return -ENOMEM; + } + + rds_info_register_func(RDS_INFO_CONNECTIONS, rds_conn_info); + rds_info_register_func(RDS_INFO_SEND_MESSAGES, + rds_conn_message_info_send); + rds_info_register_func(RDS_INFO_RETRANS_MESSAGES, + rds_conn_message_info_retrans); +#if IS_ENABLED(CONFIG_IPV6) + rds_info_register_func(RDS6_INFO_CONNECTIONS, rds6_conn_info); + rds_info_register_func(RDS6_INFO_SEND_MESSAGES, + rds6_conn_message_info_send); + rds_info_register_func(RDS6_INFO_RETRANS_MESSAGES, + rds6_conn_message_info_retrans); +#endif + return 0; +} + +void rds_conn_exit(void) +{ + rds_loop_net_exit(); /* unregister pernet callback */ + rds_loop_exit(); + + WARN_ON(!hlist_empty(rds_conn_hash)); + + kmem_cache_destroy(rds_conn_slab); + + rds_info_deregister_func(RDS_INFO_CONNECTIONS, rds_conn_info); + rds_info_deregister_func(RDS_INFO_SEND_MESSAGES, + rds_conn_message_info_send); + rds_info_deregister_func(RDS_INFO_RETRANS_MESSAGES, + rds_conn_message_info_retrans); +#if IS_ENABLED(CONFIG_IPV6) + rds_info_deregister_func(RDS6_INFO_CONNECTIONS, rds6_conn_info); + rds_info_deregister_func(RDS6_INFO_SEND_MESSAGES, + rds6_conn_message_info_send); + rds_info_deregister_func(RDS6_INFO_RETRANS_MESSAGES, + rds6_conn_message_info_retrans); +#endif +} + +/* + * Force a disconnect + */ +void rds_conn_path_drop(struct rds_conn_path *cp, bool destroy) +{ + atomic_set(&cp->cp_state, RDS_CONN_ERROR); + + rcu_read_lock(); + if (!destroy && rds_destroy_pending(cp->cp_conn)) { + rcu_read_unlock(); + return; + } + queue_work(rds_wq, &cp->cp_down_w); + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(rds_conn_path_drop); + +void rds_conn_drop(struct rds_connection *conn) +{ + WARN_ON(conn->c_trans->t_mp_capable); + rds_conn_path_drop(&conn->c_path[0], false); +} +EXPORT_SYMBOL_GPL(rds_conn_drop); + +/* + * If the connection is down, trigger a connect. We may have scheduled a + * delayed reconnect however - in this case we should not interfere. + */ +void rds_conn_path_connect_if_down(struct rds_conn_path *cp) +{ + rcu_read_lock(); + if (rds_destroy_pending(cp->cp_conn)) { + rcu_read_unlock(); + return; + } + if (rds_conn_path_state(cp) == RDS_CONN_DOWN && + !test_and_set_bit(RDS_RECONNECT_PENDING, &cp->cp_flags)) + queue_delayed_work(rds_wq, &cp->cp_conn_w, 0); + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(rds_conn_path_connect_if_down); + +/* Check connectivity of all paths + */ +void rds_check_all_paths(struct rds_connection *conn) +{ + int i = 0; + + do { + rds_conn_path_connect_if_down(&conn->c_path[i]); + } while (++i < conn->c_npaths); +} + +void rds_conn_connect_if_down(struct rds_connection *conn) +{ + WARN_ON(conn->c_trans->t_mp_capable); + rds_conn_path_connect_if_down(&conn->c_path[0]); +} +EXPORT_SYMBOL_GPL(rds_conn_connect_if_down); + +void +__rds_conn_path_error(struct rds_conn_path *cp, const char *fmt, ...) +{ + va_list ap; + + va_start(ap, fmt); + vprintk(fmt, ap); + va_end(ap); + + rds_conn_path_drop(cp, false); +} |