123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487 |
- // SPDX-License-Identifier: GPL-2.0-or-later
- /* RxRPC virtual connection handler, common bits.
- *
- * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells ([email protected])
- */
- #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
- #include <linux/module.h>
- #include <linux/slab.h>
- #include <linux/net.h>
- #include <linux/skbuff.h>
- #include "ar-internal.h"
- /*
- * Time till a connection expires after last use (in seconds).
- */
- unsigned int __read_mostly rxrpc_connection_expiry = 10 * 60;
- unsigned int __read_mostly rxrpc_closed_conn_expiry = 10;
- static void rxrpc_destroy_connection(struct rcu_head *);
- static void rxrpc_connection_timer(struct timer_list *timer)
- {
- struct rxrpc_connection *conn =
- container_of(timer, struct rxrpc_connection, timer);
- rxrpc_queue_conn(conn);
- }
- /*
- * allocate a new connection
- */
- struct rxrpc_connection *rxrpc_alloc_connection(gfp_t gfp)
- {
- struct rxrpc_connection *conn;
- _enter("");
- conn = kzalloc(sizeof(struct rxrpc_connection), gfp);
- if (conn) {
- INIT_LIST_HEAD(&conn->cache_link);
- timer_setup(&conn->timer, &rxrpc_connection_timer, 0);
- INIT_WORK(&conn->processor, &rxrpc_process_connection);
- INIT_LIST_HEAD(&conn->proc_link);
- INIT_LIST_HEAD(&conn->link);
- skb_queue_head_init(&conn->rx_queue);
- conn->security = &rxrpc_no_security;
- spin_lock_init(&conn->state_lock);
- conn->debug_id = atomic_inc_return(&rxrpc_debug_id);
- conn->idle_timestamp = jiffies;
- }
- _leave(" = %p{%d}", conn, conn ? conn->debug_id : 0);
- return conn;
- }
- /*
- * Look up a connection in the cache by protocol parameters.
- *
- * If successful, a pointer to the connection is returned, but no ref is taken.
- * NULL is returned if there is no match.
- *
- * When searching for a service call, if we find a peer but no connection, we
- * return that through *_peer in case we need to create a new service call.
- *
- * The caller must be holding the RCU read lock.
- */
- struct rxrpc_connection *rxrpc_find_connection_rcu(struct rxrpc_local *local,
- struct sk_buff *skb,
- struct rxrpc_peer **_peer)
- {
- struct rxrpc_connection *conn;
- struct rxrpc_conn_proto k;
- struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
- struct sockaddr_rxrpc srx;
- struct rxrpc_peer *peer;
- _enter(",%x", sp->hdr.cid & RXRPC_CIDMASK);
- if (rxrpc_extract_addr_from_skb(&srx, skb) < 0)
- goto not_found;
- if (srx.transport.family != local->srx.transport.family &&
- (srx.transport.family == AF_INET &&
- local->srx.transport.family != AF_INET6)) {
- pr_warn_ratelimited("AF_RXRPC: Protocol mismatch %u not %u\n",
- srx.transport.family,
- local->srx.transport.family);
- goto not_found;
- }
- k.epoch = sp->hdr.epoch;
- k.cid = sp->hdr.cid & RXRPC_CIDMASK;
- if (rxrpc_to_server(sp)) {
- /* We need to look up service connections by the full protocol
- * parameter set. We look up the peer first as an intermediate
- * step and then the connection from the peer's tree.
- */
- peer = rxrpc_lookup_peer_rcu(local, &srx);
- if (!peer)
- goto not_found;
- *_peer = peer;
- conn = rxrpc_find_service_conn_rcu(peer, skb);
- if (!conn || refcount_read(&conn->ref) == 0)
- goto not_found;
- _leave(" = %p", conn);
- return conn;
- } else {
- /* Look up client connections by connection ID alone as their
- * IDs are unique for this machine.
- */
- conn = idr_find(&rxrpc_client_conn_ids,
- sp->hdr.cid >> RXRPC_CIDSHIFT);
- if (!conn || refcount_read(&conn->ref) == 0) {
- _debug("no conn");
- goto not_found;
- }
- if (conn->proto.epoch != k.epoch ||
- conn->params.local != local)
- goto not_found;
- peer = conn->params.peer;
- switch (srx.transport.family) {
- case AF_INET:
- if (peer->srx.transport.sin.sin_port !=
- srx.transport.sin.sin_port ||
- peer->srx.transport.sin.sin_addr.s_addr !=
- srx.transport.sin.sin_addr.s_addr)
- goto not_found;
- break;
- #ifdef CONFIG_AF_RXRPC_IPV6
- case AF_INET6:
- if (peer->srx.transport.sin6.sin6_port !=
- srx.transport.sin6.sin6_port ||
- memcmp(&peer->srx.transport.sin6.sin6_addr,
- &srx.transport.sin6.sin6_addr,
- sizeof(struct in6_addr)) != 0)
- goto not_found;
- break;
- #endif
- default:
- BUG();
- }
- _leave(" = %p", conn);
- return conn;
- }
- not_found:
- _leave(" = NULL");
- return NULL;
- }
- /*
- * Disconnect a call and clear any channel it occupies when that call
- * terminates. The caller must hold the channel_lock and must release the
- * call's ref on the connection.
- */
- void __rxrpc_disconnect_call(struct rxrpc_connection *conn,
- struct rxrpc_call *call)
- {
- struct rxrpc_channel *chan =
- &conn->channels[call->cid & RXRPC_CHANNELMASK];
- _enter("%d,%x", conn->debug_id, call->cid);
- if (rcu_access_pointer(chan->call) == call) {
- /* Save the result of the call so that we can repeat it if necessary
- * through the channel, whilst disposing of the actual call record.
- */
- trace_rxrpc_disconnect_call(call);
- switch (call->completion) {
- case RXRPC_CALL_SUCCEEDED:
- chan->last_seq = call->rx_hard_ack;
- chan->last_type = RXRPC_PACKET_TYPE_ACK;
- break;
- case RXRPC_CALL_LOCALLY_ABORTED:
- chan->last_abort = call->abort_code;
- chan->last_type = RXRPC_PACKET_TYPE_ABORT;
- break;
- default:
- chan->last_abort = RX_CALL_DEAD;
- chan->last_type = RXRPC_PACKET_TYPE_ABORT;
- break;
- }
- /* Sync with rxrpc_conn_retransmit(). */
- smp_wmb();
- chan->last_call = chan->call_id;
- chan->call_id = chan->call_counter;
- rcu_assign_pointer(chan->call, NULL);
- }
- _leave("");
- }
- /*
- * Disconnect a call and clear any channel it occupies when that call
- * terminates.
- */
- void rxrpc_disconnect_call(struct rxrpc_call *call)
- {
- struct rxrpc_connection *conn = call->conn;
- call->peer->cong_cwnd = call->cong_cwnd;
- if (!hlist_unhashed(&call->error_link)) {
- spin_lock_bh(&call->peer->lock);
- hlist_del_rcu(&call->error_link);
- spin_unlock_bh(&call->peer->lock);
- }
- if (rxrpc_is_client_call(call))
- return rxrpc_disconnect_client_call(conn->bundle, call);
- spin_lock(&conn->bundle->channel_lock);
- __rxrpc_disconnect_call(conn, call);
- spin_unlock(&conn->bundle->channel_lock);
- set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
- conn->idle_timestamp = jiffies;
- }
- /*
- * Kill off a connection.
- */
- void rxrpc_kill_connection(struct rxrpc_connection *conn)
- {
- struct rxrpc_net *rxnet = conn->params.local->rxnet;
- ASSERT(!rcu_access_pointer(conn->channels[0].call) &&
- !rcu_access_pointer(conn->channels[1].call) &&
- !rcu_access_pointer(conn->channels[2].call) &&
- !rcu_access_pointer(conn->channels[3].call));
- ASSERT(list_empty(&conn->cache_link));
- write_lock(&rxnet->conn_lock);
- list_del_init(&conn->proc_link);
- write_unlock(&rxnet->conn_lock);
- /* Drain the Rx queue. Note that even though we've unpublished, an
- * incoming packet could still be being added to our Rx queue, so we
- * will need to drain it again in the RCU cleanup handler.
- */
- rxrpc_purge_queue(&conn->rx_queue);
- /* Leave final destruction to RCU. The connection processor work item
- * must carry a ref on the connection to prevent us getting here whilst
- * it is queued or running.
- */
- call_rcu(&conn->rcu, rxrpc_destroy_connection);
- }
- /*
- * Queue a connection's work processor, getting a ref to pass to the work
- * queue.
- */
- bool rxrpc_queue_conn(struct rxrpc_connection *conn)
- {
- const void *here = __builtin_return_address(0);
- int r;
- if (!__refcount_inc_not_zero(&conn->ref, &r))
- return false;
- if (rxrpc_queue_work(&conn->processor))
- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_queued, r + 1, here);
- else
- rxrpc_put_connection(conn);
- return true;
- }
- /*
- * Note the re-emergence of a connection.
- */
- void rxrpc_see_connection(struct rxrpc_connection *conn)
- {
- const void *here = __builtin_return_address(0);
- if (conn) {
- int n = refcount_read(&conn->ref);
- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_seen, n, here);
- }
- }
- /*
- * Get a ref on a connection.
- */
- struct rxrpc_connection *rxrpc_get_connection(struct rxrpc_connection *conn)
- {
- const void *here = __builtin_return_address(0);
- int r;
- __refcount_inc(&conn->ref, &r);
- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_got, r, here);
- return conn;
- }
- /*
- * Try to get a ref on a connection.
- */
- struct rxrpc_connection *
- rxrpc_get_connection_maybe(struct rxrpc_connection *conn)
- {
- const void *here = __builtin_return_address(0);
- int r;
- if (conn) {
- if (__refcount_inc_not_zero(&conn->ref, &r))
- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_got, r + 1, here);
- else
- conn = NULL;
- }
- return conn;
- }
- /*
- * Set the service connection reap timer.
- */
- static void rxrpc_set_service_reap_timer(struct rxrpc_net *rxnet,
- unsigned long reap_at)
- {
- if (rxnet->live)
- timer_reduce(&rxnet->service_conn_reap_timer, reap_at);
- }
- /*
- * Release a service connection
- */
- void rxrpc_put_service_conn(struct rxrpc_connection *conn)
- {
- const void *here = __builtin_return_address(0);
- unsigned int debug_id = conn->debug_id;
- int r;
- __refcount_dec(&conn->ref, &r);
- trace_rxrpc_conn(debug_id, rxrpc_conn_put_service, r - 1, here);
- if (r - 1 == 1)
- rxrpc_set_service_reap_timer(conn->params.local->rxnet,
- jiffies + rxrpc_connection_expiry);
- }
- /*
- * destroy a virtual connection
- */
- static void rxrpc_destroy_connection(struct rcu_head *rcu)
- {
- struct rxrpc_connection *conn =
- container_of(rcu, struct rxrpc_connection, rcu);
- _enter("{%d,u=%d}", conn->debug_id, refcount_read(&conn->ref));
- ASSERTCMP(refcount_read(&conn->ref), ==, 0);
- _net("DESTROY CONN %d", conn->debug_id);
- del_timer_sync(&conn->timer);
- rxrpc_purge_queue(&conn->rx_queue);
- conn->security->clear(conn);
- key_put(conn->params.key);
- rxrpc_put_bundle(conn->bundle);
- rxrpc_put_peer(conn->params.peer);
- if (atomic_dec_and_test(&conn->params.local->rxnet->nr_conns))
- wake_up_var(&conn->params.local->rxnet->nr_conns);
- rxrpc_put_local(conn->params.local);
- kfree(conn);
- _leave("");
- }
- /*
- * reap dead service connections
- */
- void rxrpc_service_connection_reaper(struct work_struct *work)
- {
- struct rxrpc_connection *conn, *_p;
- struct rxrpc_net *rxnet =
- container_of(work, struct rxrpc_net, service_conn_reaper);
- unsigned long expire_at, earliest, idle_timestamp, now;
- LIST_HEAD(graveyard);
- _enter("");
- now = jiffies;
- earliest = now + MAX_JIFFY_OFFSET;
- write_lock(&rxnet->conn_lock);
- list_for_each_entry_safe(conn, _p, &rxnet->service_conns, link) {
- ASSERTCMP(refcount_read(&conn->ref), >, 0);
- if (likely(refcount_read(&conn->ref) > 1))
- continue;
- if (conn->state == RXRPC_CONN_SERVICE_PREALLOC)
- continue;
- if (rxnet->live && !conn->params.local->dead) {
- idle_timestamp = READ_ONCE(conn->idle_timestamp);
- expire_at = idle_timestamp + rxrpc_connection_expiry * HZ;
- if (conn->params.local->service_closed)
- expire_at = idle_timestamp + rxrpc_closed_conn_expiry * HZ;
- _debug("reap CONN %d { u=%d,t=%ld }",
- conn->debug_id, refcount_read(&conn->ref),
- (long)expire_at - (long)now);
- if (time_before(now, expire_at)) {
- if (time_before(expire_at, earliest))
- earliest = expire_at;
- continue;
- }
- }
- /* The usage count sits at 1 whilst the object is unused on the
- * list; we reduce that to 0 to make the object unavailable.
- */
- if (!refcount_dec_if_one(&conn->ref))
- continue;
- trace_rxrpc_conn(conn->debug_id, rxrpc_conn_reap_service, 0, NULL);
- if (rxrpc_conn_is_client(conn))
- BUG();
- else
- rxrpc_unpublish_service_conn(conn);
- list_move_tail(&conn->link, &graveyard);
- }
- write_unlock(&rxnet->conn_lock);
- if (earliest != now + MAX_JIFFY_OFFSET) {
- _debug("reschedule reaper %ld", (long)earliest - (long)now);
- ASSERT(time_after(earliest, now));
- rxrpc_set_service_reap_timer(rxnet, earliest);
- }
- while (!list_empty(&graveyard)) {
- conn = list_entry(graveyard.next, struct rxrpc_connection,
- link);
- list_del_init(&conn->link);
- ASSERTCMP(refcount_read(&conn->ref), ==, 0);
- rxrpc_kill_connection(conn);
- }
- _leave("");
- }
- /*
- * preemptively destroy all the service connection records rather than
- * waiting for them to time out
- */
- void rxrpc_destroy_all_connections(struct rxrpc_net *rxnet)
- {
- struct rxrpc_connection *conn, *_p;
- bool leak = false;
- _enter("");
- atomic_dec(&rxnet->nr_conns);
- rxrpc_destroy_all_client_connections(rxnet);
- del_timer_sync(&rxnet->service_conn_reap_timer);
- rxrpc_queue_work(&rxnet->service_conn_reaper);
- flush_workqueue(rxrpc_workqueue);
- write_lock(&rxnet->conn_lock);
- list_for_each_entry_safe(conn, _p, &rxnet->service_conns, link) {
- pr_err("AF_RXRPC: Leaked conn %p {%d}\n",
- conn, refcount_read(&conn->ref));
- leak = true;
- }
- write_unlock(&rxnet->conn_lock);
- BUG_ON(leak);
- ASSERT(list_empty(&rxnet->conn_proc_list));
- /* We need to wait for the connections to be destroyed by RCU as they
- * pin things that we still need to get rid of.
- */
- wait_var_event(&rxnet->nr_conns, !atomic_read(&rxnet->nr_conns));
- _leave("");
- }
|