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-rw-r--r--net/rxrpc/conn_object.c487
1 files changed, 487 insertions, 0 deletions
diff --git a/net/rxrpc/conn_object.c b/net/rxrpc/conn_object.c
new file mode 100644
index 000000000..22089e37e
--- /dev/null
+++ b/net/rxrpc/conn_object.c
@@ -0,0 +1,487 @@
+// 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 (dhowells@redhat.com)
+ */
+
+#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("");
+}
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