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![David Howells](/assets/img/avatar_default.png)
Merge the ->prime_packet_security() into the ->init_connection_security() hook as they're always called together. Signed-off-by: David Howells <dhowells@redhat.com>
1117 lines
29 KiB
C
1117 lines
29 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/* Client connection-specific management code.
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*
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* Copyright (C) 2016, 2020 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* Client connections need to be cached for a little while after they've made a
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* call so as to handle retransmitted DATA packets in case the server didn't
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* receive the final ACK or terminating ABORT we sent it.
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*
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* There are flags of relevance to the cache:
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*
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* (2) DONT_REUSE - The connection should be discarded as soon as possible and
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* should not be reused. This is set when an exclusive connection is used
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* or a call ID counter overflows.
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*
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* The caching state may only be changed if the cache lock is held.
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*
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* There are two idle client connection expiry durations. If the total number
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* of connections is below the reap threshold, we use the normal duration; if
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* it's above, we use the fast duration.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/slab.h>
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#include <linux/idr.h>
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#include <linux/timer.h>
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#include <linux/sched/signal.h>
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#include "ar-internal.h"
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__read_mostly unsigned int rxrpc_reap_client_connections = 900;
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__read_mostly unsigned long rxrpc_conn_idle_client_expiry = 2 * 60 * HZ;
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__read_mostly unsigned long rxrpc_conn_idle_client_fast_expiry = 2 * HZ;
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/*
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* We use machine-unique IDs for our client connections.
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*/
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DEFINE_IDR(rxrpc_client_conn_ids);
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static DEFINE_SPINLOCK(rxrpc_conn_id_lock);
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/*
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* Get a connection ID and epoch for a client connection from the global pool.
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* The connection struct pointer is then recorded in the idr radix tree. The
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* epoch doesn't change until the client is rebooted (or, at least, unless the
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* module is unloaded).
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*/
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static int rxrpc_get_client_connection_id(struct rxrpc_connection *conn,
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gfp_t gfp)
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{
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struct rxrpc_net *rxnet = conn->params.local->rxnet;
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int id;
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_enter("");
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idr_preload(gfp);
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spin_lock(&rxrpc_conn_id_lock);
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id = idr_alloc_cyclic(&rxrpc_client_conn_ids, conn,
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1, 0x40000000, GFP_NOWAIT);
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if (id < 0)
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goto error;
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spin_unlock(&rxrpc_conn_id_lock);
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idr_preload_end();
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conn->proto.epoch = rxnet->epoch;
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conn->proto.cid = id << RXRPC_CIDSHIFT;
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set_bit(RXRPC_CONN_HAS_IDR, &conn->flags);
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_leave(" [CID %x]", conn->proto.cid);
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return 0;
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error:
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spin_unlock(&rxrpc_conn_id_lock);
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idr_preload_end();
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_leave(" = %d", id);
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return id;
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}
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/*
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* Release a connection ID for a client connection from the global pool.
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*/
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static void rxrpc_put_client_connection_id(struct rxrpc_connection *conn)
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{
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if (test_bit(RXRPC_CONN_HAS_IDR, &conn->flags)) {
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spin_lock(&rxrpc_conn_id_lock);
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idr_remove(&rxrpc_client_conn_ids,
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conn->proto.cid >> RXRPC_CIDSHIFT);
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spin_unlock(&rxrpc_conn_id_lock);
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}
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}
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/*
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* Destroy the client connection ID tree.
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*/
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void rxrpc_destroy_client_conn_ids(void)
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{
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struct rxrpc_connection *conn;
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int id;
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if (!idr_is_empty(&rxrpc_client_conn_ids)) {
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idr_for_each_entry(&rxrpc_client_conn_ids, conn, id) {
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pr_err("AF_RXRPC: Leaked client conn %p {%d}\n",
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conn, atomic_read(&conn->usage));
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}
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BUG();
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}
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idr_destroy(&rxrpc_client_conn_ids);
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}
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/*
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* Allocate a connection bundle.
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*/
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static struct rxrpc_bundle *rxrpc_alloc_bundle(struct rxrpc_conn_parameters *cp,
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gfp_t gfp)
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{
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struct rxrpc_bundle *bundle;
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bundle = kzalloc(sizeof(*bundle), gfp);
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if (bundle) {
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bundle->params = *cp;
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rxrpc_get_peer(bundle->params.peer);
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atomic_set(&bundle->usage, 1);
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spin_lock_init(&bundle->channel_lock);
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INIT_LIST_HEAD(&bundle->waiting_calls);
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}
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return bundle;
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}
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struct rxrpc_bundle *rxrpc_get_bundle(struct rxrpc_bundle *bundle)
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{
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atomic_inc(&bundle->usage);
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return bundle;
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}
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void rxrpc_put_bundle(struct rxrpc_bundle *bundle)
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{
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unsigned int d = bundle->debug_id;
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unsigned int u = atomic_dec_return(&bundle->usage);
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_debug("PUT B=%x %u", d, u);
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if (u == 0) {
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rxrpc_put_peer(bundle->params.peer);
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kfree(bundle);
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}
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}
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/*
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* Allocate a client connection.
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*/
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static struct rxrpc_connection *
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rxrpc_alloc_client_connection(struct rxrpc_bundle *bundle, gfp_t gfp)
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{
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struct rxrpc_connection *conn;
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struct rxrpc_net *rxnet = bundle->params.local->rxnet;
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int ret;
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_enter("");
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conn = rxrpc_alloc_connection(gfp);
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if (!conn) {
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_leave(" = -ENOMEM");
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return ERR_PTR(-ENOMEM);
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}
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atomic_set(&conn->usage, 1);
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conn->bundle = bundle;
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conn->params = bundle->params;
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conn->out_clientflag = RXRPC_CLIENT_INITIATED;
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conn->state = RXRPC_CONN_CLIENT;
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conn->service_id = conn->params.service_id;
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ret = rxrpc_get_client_connection_id(conn, gfp);
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if (ret < 0)
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goto error_0;
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ret = rxrpc_init_client_conn_security(conn);
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if (ret < 0)
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goto error_1;
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atomic_inc(&rxnet->nr_conns);
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write_lock(&rxnet->conn_lock);
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list_add_tail(&conn->proc_link, &rxnet->conn_proc_list);
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write_unlock(&rxnet->conn_lock);
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rxrpc_get_bundle(bundle);
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rxrpc_get_peer(conn->params.peer);
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rxrpc_get_local(conn->params.local);
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key_get(conn->params.key);
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trace_rxrpc_conn(conn->debug_id, rxrpc_conn_new_client,
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atomic_read(&conn->usage),
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__builtin_return_address(0));
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atomic_inc(&rxnet->nr_client_conns);
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trace_rxrpc_client(conn, -1, rxrpc_client_alloc);
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_leave(" = %p", conn);
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return conn;
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error_1:
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rxrpc_put_client_connection_id(conn);
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error_0:
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kfree(conn);
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_leave(" = %d", ret);
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return ERR_PTR(ret);
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}
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/*
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* Determine if a connection may be reused.
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*/
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static bool rxrpc_may_reuse_conn(struct rxrpc_connection *conn)
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{
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struct rxrpc_net *rxnet;
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int id_cursor, id, distance, limit;
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if (!conn)
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goto dont_reuse;
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rxnet = conn->params.local->rxnet;
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if (test_bit(RXRPC_CONN_DONT_REUSE, &conn->flags))
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goto dont_reuse;
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if (conn->state != RXRPC_CONN_CLIENT ||
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conn->proto.epoch != rxnet->epoch)
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goto mark_dont_reuse;
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/* The IDR tree gets very expensive on memory if the connection IDs are
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* widely scattered throughout the number space, so we shall want to
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* kill off connections that, say, have an ID more than about four
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* times the maximum number of client conns away from the current
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* allocation point to try and keep the IDs concentrated.
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*/
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id_cursor = idr_get_cursor(&rxrpc_client_conn_ids);
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id = conn->proto.cid >> RXRPC_CIDSHIFT;
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distance = id - id_cursor;
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if (distance < 0)
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distance = -distance;
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limit = max_t(unsigned long, atomic_read(&rxnet->nr_conns) * 4, 1024);
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if (distance > limit)
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goto mark_dont_reuse;
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return true;
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mark_dont_reuse:
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set_bit(RXRPC_CONN_DONT_REUSE, &conn->flags);
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dont_reuse:
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return false;
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}
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/*
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* Look up the conn bundle that matches the connection parameters, adding it if
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* it doesn't yet exist.
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*/
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static struct rxrpc_bundle *rxrpc_look_up_bundle(struct rxrpc_conn_parameters *cp,
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gfp_t gfp)
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{
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static atomic_t rxrpc_bundle_id;
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struct rxrpc_bundle *bundle, *candidate;
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struct rxrpc_local *local = cp->local;
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struct rb_node *p, **pp, *parent;
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long diff;
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_enter("{%px,%x,%u,%u}",
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cp->peer, key_serial(cp->key), cp->security_level, cp->upgrade);
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if (cp->exclusive)
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return rxrpc_alloc_bundle(cp, gfp);
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/* First, see if the bundle is already there. */
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_debug("search 1");
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spin_lock(&local->client_bundles_lock);
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p = local->client_bundles.rb_node;
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while (p) {
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bundle = rb_entry(p, struct rxrpc_bundle, local_node);
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#define cmp(X) ((long)bundle->params.X - (long)cp->X)
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diff = (cmp(peer) ?:
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cmp(key) ?:
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cmp(security_level) ?:
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cmp(upgrade));
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#undef cmp
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if (diff < 0)
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p = p->rb_left;
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else if (diff > 0)
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p = p->rb_right;
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else
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goto found_bundle;
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}
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spin_unlock(&local->client_bundles_lock);
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_debug("not found");
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/* It wasn't. We need to add one. */
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candidate = rxrpc_alloc_bundle(cp, gfp);
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if (!candidate)
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return NULL;
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_debug("search 2");
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spin_lock(&local->client_bundles_lock);
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pp = &local->client_bundles.rb_node;
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parent = NULL;
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while (*pp) {
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parent = *pp;
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bundle = rb_entry(parent, struct rxrpc_bundle, local_node);
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#define cmp(X) ((long)bundle->params.X - (long)cp->X)
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diff = (cmp(peer) ?:
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cmp(key) ?:
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cmp(security_level) ?:
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cmp(upgrade));
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#undef cmp
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if (diff < 0)
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pp = &(*pp)->rb_left;
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else if (diff > 0)
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pp = &(*pp)->rb_right;
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else
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goto found_bundle_free;
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}
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_debug("new bundle");
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candidate->debug_id = atomic_inc_return(&rxrpc_bundle_id);
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rb_link_node(&candidate->local_node, parent, pp);
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rb_insert_color(&candidate->local_node, &local->client_bundles);
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rxrpc_get_bundle(candidate);
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spin_unlock(&local->client_bundles_lock);
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_leave(" = %u [new]", candidate->debug_id);
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return candidate;
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found_bundle_free:
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kfree(candidate);
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found_bundle:
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rxrpc_get_bundle(bundle);
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spin_unlock(&local->client_bundles_lock);
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_leave(" = %u [found]", bundle->debug_id);
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return bundle;
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}
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/*
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* Create or find a client bundle to use for a call.
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*
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* If we return with a connection, the call will be on its waiting list. It's
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* left to the caller to assign a channel and wake up the call.
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*/
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static struct rxrpc_bundle *rxrpc_prep_call(struct rxrpc_sock *rx,
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struct rxrpc_call *call,
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struct rxrpc_conn_parameters *cp,
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struct sockaddr_rxrpc *srx,
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gfp_t gfp)
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{
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struct rxrpc_bundle *bundle;
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_enter("{%d,%lx},", call->debug_id, call->user_call_ID);
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cp->peer = rxrpc_lookup_peer(rx, cp->local, srx, gfp);
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if (!cp->peer)
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goto error;
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call->cong_cwnd = cp->peer->cong_cwnd;
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if (call->cong_cwnd >= call->cong_ssthresh)
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call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
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else
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call->cong_mode = RXRPC_CALL_SLOW_START;
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if (cp->upgrade)
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__set_bit(RXRPC_CALL_UPGRADE, &call->flags);
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/* Find the client connection bundle. */
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bundle = rxrpc_look_up_bundle(cp, gfp);
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if (!bundle)
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goto error;
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|
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/* Get this call queued. Someone else may activate it whilst we're
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* lining up a new connection, but that's fine.
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*/
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spin_lock(&bundle->channel_lock);
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list_add_tail(&call->chan_wait_link, &bundle->waiting_calls);
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spin_unlock(&bundle->channel_lock);
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_leave(" = [B=%x]", bundle->debug_id);
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return bundle;
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error:
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_leave(" = -ENOMEM");
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return ERR_PTR(-ENOMEM);
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}
|
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|
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/*
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* Allocate a new connection and add it into a bundle.
|
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*/
|
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static void rxrpc_add_conn_to_bundle(struct rxrpc_bundle *bundle, gfp_t gfp)
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__releases(bundle->channel_lock)
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{
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struct rxrpc_connection *candidate = NULL, *old = NULL;
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bool conflict;
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int i;
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|
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_enter("");
|
|
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conflict = bundle->alloc_conn;
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if (!conflict)
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bundle->alloc_conn = true;
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spin_unlock(&bundle->channel_lock);
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if (conflict) {
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_leave(" [conf]");
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return;
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}
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|
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candidate = rxrpc_alloc_client_connection(bundle, gfp);
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|
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spin_lock(&bundle->channel_lock);
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bundle->alloc_conn = false;
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|
|
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if (IS_ERR(candidate)) {
|
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bundle->alloc_error = PTR_ERR(candidate);
|
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spin_unlock(&bundle->channel_lock);
|
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_leave(" [err %ld]", PTR_ERR(candidate));
|
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return;
|
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}
|
|
|
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bundle->alloc_error = 0;
|
|
|
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for (i = 0; i < ARRAY_SIZE(bundle->conns); i++) {
|
|
unsigned int shift = i * RXRPC_MAXCALLS;
|
|
int j;
|
|
|
|
old = bundle->conns[i];
|
|
if (!rxrpc_may_reuse_conn(old)) {
|
|
if (old)
|
|
trace_rxrpc_client(old, -1, rxrpc_client_replace);
|
|
candidate->bundle_shift = shift;
|
|
bundle->conns[i] = candidate;
|
|
for (j = 0; j < RXRPC_MAXCALLS; j++)
|
|
set_bit(shift + j, &bundle->avail_chans);
|
|
candidate = NULL;
|
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break;
|
|
}
|
|
|
|
old = NULL;
|
|
}
|
|
|
|
spin_unlock(&bundle->channel_lock);
|
|
|
|
if (candidate) {
|
|
_debug("discard C=%x", candidate->debug_id);
|
|
trace_rxrpc_client(candidate, -1, rxrpc_client_duplicate);
|
|
rxrpc_put_connection(candidate);
|
|
}
|
|
|
|
rxrpc_put_connection(old);
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* Add a connection to a bundle if there are no usable connections or we have
|
|
* connections waiting for extra capacity.
|
|
*/
|
|
static void rxrpc_maybe_add_conn(struct rxrpc_bundle *bundle, gfp_t gfp)
|
|
{
|
|
struct rxrpc_call *call;
|
|
int i, usable;
|
|
|
|
_enter("");
|
|
|
|
spin_lock(&bundle->channel_lock);
|
|
|
|
/* See if there are any usable connections. */
|
|
usable = 0;
|
|
for (i = 0; i < ARRAY_SIZE(bundle->conns); i++)
|
|
if (rxrpc_may_reuse_conn(bundle->conns[i]))
|
|
usable++;
|
|
|
|
if (!usable && !list_empty(&bundle->waiting_calls)) {
|
|
call = list_first_entry(&bundle->waiting_calls,
|
|
struct rxrpc_call, chan_wait_link);
|
|
if (test_bit(RXRPC_CALL_UPGRADE, &call->flags))
|
|
bundle->try_upgrade = true;
|
|
}
|
|
|
|
if (!usable)
|
|
goto alloc_conn;
|
|
|
|
if (!bundle->avail_chans &&
|
|
!bundle->try_upgrade &&
|
|
!list_empty(&bundle->waiting_calls) &&
|
|
usable < ARRAY_SIZE(bundle->conns))
|
|
goto alloc_conn;
|
|
|
|
spin_unlock(&bundle->channel_lock);
|
|
_leave("");
|
|
return;
|
|
|
|
alloc_conn:
|
|
return rxrpc_add_conn_to_bundle(bundle, gfp);
|
|
}
|
|
|
|
/*
|
|
* Assign a channel to the call at the front of the queue and wake the call up.
|
|
* We don't increment the callNumber counter until this number has been exposed
|
|
* to the world.
|
|
*/
|
|
static void rxrpc_activate_one_channel(struct rxrpc_connection *conn,
|
|
unsigned int channel)
|
|
{
|
|
struct rxrpc_channel *chan = &conn->channels[channel];
|
|
struct rxrpc_bundle *bundle = conn->bundle;
|
|
struct rxrpc_call *call = list_entry(bundle->waiting_calls.next,
|
|
struct rxrpc_call, chan_wait_link);
|
|
u32 call_id = chan->call_counter + 1;
|
|
|
|
_enter("C=%x,%u", conn->debug_id, channel);
|
|
|
|
trace_rxrpc_client(conn, channel, rxrpc_client_chan_activate);
|
|
|
|
/* Cancel the final ACK on the previous call if it hasn't been sent yet
|
|
* as the DATA packet will implicitly ACK it.
|
|
*/
|
|
clear_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags);
|
|
clear_bit(conn->bundle_shift + channel, &bundle->avail_chans);
|
|
|
|
rxrpc_see_call(call);
|
|
list_del_init(&call->chan_wait_link);
|
|
call->peer = rxrpc_get_peer(conn->params.peer);
|
|
call->conn = rxrpc_get_connection(conn);
|
|
call->cid = conn->proto.cid | channel;
|
|
call->call_id = call_id;
|
|
call->security = conn->security;
|
|
call->security_ix = conn->security_ix;
|
|
call->service_id = conn->service_id;
|
|
|
|
trace_rxrpc_connect_call(call);
|
|
_net("CONNECT call %08x:%08x as call %d on conn %d",
|
|
call->cid, call->call_id, call->debug_id, conn->debug_id);
|
|
|
|
write_lock_bh(&call->state_lock);
|
|
call->state = RXRPC_CALL_CLIENT_SEND_REQUEST;
|
|
write_unlock_bh(&call->state_lock);
|
|
|
|
/* Paired with the read barrier in rxrpc_connect_call(). This orders
|
|
* cid and epoch in the connection wrt to call_id without the need to
|
|
* take the channel_lock.
|
|
*
|
|
* We provisionally assign a callNumber at this point, but we don't
|
|
* confirm it until the call is about to be exposed.
|
|
*
|
|
* TODO: Pair with a barrier in the data_ready handler when that looks
|
|
* at the call ID through a connection channel.
|
|
*/
|
|
smp_wmb();
|
|
|
|
chan->call_id = call_id;
|
|
chan->call_debug_id = call->debug_id;
|
|
rcu_assign_pointer(chan->call, call);
|
|
wake_up(&call->waitq);
|
|
}
|
|
|
|
/*
|
|
* Remove a connection from the idle list if it's on it.
|
|
*/
|
|
static void rxrpc_unidle_conn(struct rxrpc_bundle *bundle, struct rxrpc_connection *conn)
|
|
{
|
|
struct rxrpc_net *rxnet = bundle->params.local->rxnet;
|
|
bool drop_ref;
|
|
|
|
if (!list_empty(&conn->cache_link)) {
|
|
drop_ref = false;
|
|
spin_lock(&rxnet->client_conn_cache_lock);
|
|
if (!list_empty(&conn->cache_link)) {
|
|
list_del_init(&conn->cache_link);
|
|
drop_ref = true;
|
|
}
|
|
spin_unlock(&rxnet->client_conn_cache_lock);
|
|
if (drop_ref)
|
|
rxrpc_put_connection(conn);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Assign channels and callNumbers to waiting calls with channel_lock
|
|
* held by caller.
|
|
*/
|
|
static void rxrpc_activate_channels_locked(struct rxrpc_bundle *bundle)
|
|
{
|
|
struct rxrpc_connection *conn;
|
|
unsigned long avail, mask;
|
|
unsigned int channel, slot;
|
|
|
|
if (bundle->try_upgrade)
|
|
mask = 1;
|
|
else
|
|
mask = ULONG_MAX;
|
|
|
|
while (!list_empty(&bundle->waiting_calls)) {
|
|
avail = bundle->avail_chans & mask;
|
|
if (!avail)
|
|
break;
|
|
channel = __ffs(avail);
|
|
clear_bit(channel, &bundle->avail_chans);
|
|
|
|
slot = channel / RXRPC_MAXCALLS;
|
|
conn = bundle->conns[slot];
|
|
if (!conn)
|
|
break;
|
|
|
|
if (bundle->try_upgrade)
|
|
set_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags);
|
|
rxrpc_unidle_conn(bundle, conn);
|
|
|
|
channel &= (RXRPC_MAXCALLS - 1);
|
|
conn->act_chans |= 1 << channel;
|
|
rxrpc_activate_one_channel(conn, channel);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Assign channels and callNumbers to waiting calls.
|
|
*/
|
|
static void rxrpc_activate_channels(struct rxrpc_bundle *bundle)
|
|
{
|
|
_enter("B=%x", bundle->debug_id);
|
|
|
|
trace_rxrpc_client(NULL, -1, rxrpc_client_activate_chans);
|
|
|
|
if (!bundle->avail_chans)
|
|
return;
|
|
|
|
spin_lock(&bundle->channel_lock);
|
|
rxrpc_activate_channels_locked(bundle);
|
|
spin_unlock(&bundle->channel_lock);
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* Wait for a callNumber and a channel to be granted to a call.
|
|
*/
|
|
static int rxrpc_wait_for_channel(struct rxrpc_bundle *bundle,
|
|
struct rxrpc_call *call, gfp_t gfp)
|
|
{
|
|
DECLARE_WAITQUEUE(myself, current);
|
|
int ret = 0;
|
|
|
|
_enter("%d", call->debug_id);
|
|
|
|
if (!gfpflags_allow_blocking(gfp)) {
|
|
rxrpc_maybe_add_conn(bundle, gfp);
|
|
rxrpc_activate_channels(bundle);
|
|
ret = bundle->alloc_error ?: -EAGAIN;
|
|
goto out;
|
|
}
|
|
|
|
add_wait_queue_exclusive(&call->waitq, &myself);
|
|
for (;;) {
|
|
rxrpc_maybe_add_conn(bundle, gfp);
|
|
rxrpc_activate_channels(bundle);
|
|
ret = bundle->alloc_error;
|
|
if (ret < 0)
|
|
break;
|
|
|
|
switch (call->interruptibility) {
|
|
case RXRPC_INTERRUPTIBLE:
|
|
case RXRPC_PREINTERRUPTIBLE:
|
|
set_current_state(TASK_INTERRUPTIBLE);
|
|
break;
|
|
case RXRPC_UNINTERRUPTIBLE:
|
|
default:
|
|
set_current_state(TASK_UNINTERRUPTIBLE);
|
|
break;
|
|
}
|
|
if (READ_ONCE(call->state) != RXRPC_CALL_CLIENT_AWAIT_CONN)
|
|
break;
|
|
if ((call->interruptibility == RXRPC_INTERRUPTIBLE ||
|
|
call->interruptibility == RXRPC_PREINTERRUPTIBLE) &&
|
|
signal_pending(current)) {
|
|
ret = -ERESTARTSYS;
|
|
break;
|
|
}
|
|
schedule();
|
|
}
|
|
remove_wait_queue(&call->waitq, &myself);
|
|
__set_current_state(TASK_RUNNING);
|
|
|
|
out:
|
|
_leave(" = %d", ret);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* find a connection for a call
|
|
* - called in process context with IRQs enabled
|
|
*/
|
|
int rxrpc_connect_call(struct rxrpc_sock *rx,
|
|
struct rxrpc_call *call,
|
|
struct rxrpc_conn_parameters *cp,
|
|
struct sockaddr_rxrpc *srx,
|
|
gfp_t gfp)
|
|
{
|
|
struct rxrpc_bundle *bundle;
|
|
struct rxrpc_net *rxnet = cp->local->rxnet;
|
|
int ret = 0;
|
|
|
|
_enter("{%d,%lx},", call->debug_id, call->user_call_ID);
|
|
|
|
rxrpc_discard_expired_client_conns(&rxnet->client_conn_reaper);
|
|
|
|
bundle = rxrpc_prep_call(rx, call, cp, srx, gfp);
|
|
if (IS_ERR(bundle)) {
|
|
ret = PTR_ERR(bundle);
|
|
goto out;
|
|
}
|
|
|
|
if (call->state == RXRPC_CALL_CLIENT_AWAIT_CONN) {
|
|
ret = rxrpc_wait_for_channel(bundle, call, gfp);
|
|
if (ret < 0)
|
|
goto wait_failed;
|
|
}
|
|
|
|
granted_channel:
|
|
/* Paired with the write barrier in rxrpc_activate_one_channel(). */
|
|
smp_rmb();
|
|
|
|
out_put_bundle:
|
|
rxrpc_put_bundle(bundle);
|
|
out:
|
|
_leave(" = %d", ret);
|
|
return ret;
|
|
|
|
wait_failed:
|
|
spin_lock(&bundle->channel_lock);
|
|
list_del_init(&call->chan_wait_link);
|
|
spin_unlock(&bundle->channel_lock);
|
|
|
|
if (call->state != RXRPC_CALL_CLIENT_AWAIT_CONN) {
|
|
ret = 0;
|
|
goto granted_channel;
|
|
}
|
|
|
|
trace_rxrpc_client(call->conn, ret, rxrpc_client_chan_wait_failed);
|
|
rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR, 0, ret);
|
|
rxrpc_disconnect_client_call(bundle, call);
|
|
goto out_put_bundle;
|
|
}
|
|
|
|
/*
|
|
* Note that a call, and thus a connection, is about to be exposed to the
|
|
* world.
|
|
*/
|
|
void rxrpc_expose_client_call(struct rxrpc_call *call)
|
|
{
|
|
unsigned int channel = call->cid & RXRPC_CHANNELMASK;
|
|
struct rxrpc_connection *conn = call->conn;
|
|
struct rxrpc_channel *chan = &conn->channels[channel];
|
|
|
|
if (!test_and_set_bit(RXRPC_CALL_EXPOSED, &call->flags)) {
|
|
/* Mark the call ID as being used. If the callNumber counter
|
|
* exceeds ~2 billion, we kill the connection after its
|
|
* outstanding calls have finished so that the counter doesn't
|
|
* wrap.
|
|
*/
|
|
chan->call_counter++;
|
|
if (chan->call_counter >= INT_MAX)
|
|
set_bit(RXRPC_CONN_DONT_REUSE, &conn->flags);
|
|
trace_rxrpc_client(conn, channel, rxrpc_client_exposed);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Set the reap timer.
|
|
*/
|
|
static void rxrpc_set_client_reap_timer(struct rxrpc_net *rxnet)
|
|
{
|
|
if (!rxnet->kill_all_client_conns) {
|
|
unsigned long now = jiffies;
|
|
unsigned long reap_at = now + rxrpc_conn_idle_client_expiry;
|
|
|
|
if (rxnet->live)
|
|
timer_reduce(&rxnet->client_conn_reap_timer, reap_at);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Disconnect a client call.
|
|
*/
|
|
void rxrpc_disconnect_client_call(struct rxrpc_bundle *bundle, struct rxrpc_call *call)
|
|
{
|
|
struct rxrpc_connection *conn;
|
|
struct rxrpc_channel *chan = NULL;
|
|
struct rxrpc_net *rxnet = bundle->params.local->rxnet;
|
|
unsigned int channel;
|
|
bool may_reuse;
|
|
u32 cid;
|
|
|
|
_enter("c=%x", call->debug_id);
|
|
|
|
spin_lock(&bundle->channel_lock);
|
|
set_bit(RXRPC_CALL_DISCONNECTED, &call->flags);
|
|
|
|
/* Calls that have never actually been assigned a channel can simply be
|
|
* discarded.
|
|
*/
|
|
conn = call->conn;
|
|
if (!conn) {
|
|
_debug("call is waiting");
|
|
ASSERTCMP(call->call_id, ==, 0);
|
|
ASSERT(!test_bit(RXRPC_CALL_EXPOSED, &call->flags));
|
|
list_del_init(&call->chan_wait_link);
|
|
goto out;
|
|
}
|
|
|
|
cid = call->cid;
|
|
channel = cid & RXRPC_CHANNELMASK;
|
|
chan = &conn->channels[channel];
|
|
trace_rxrpc_client(conn, channel, rxrpc_client_chan_disconnect);
|
|
|
|
if (rcu_access_pointer(chan->call) != call) {
|
|
spin_unlock(&bundle->channel_lock);
|
|
BUG();
|
|
}
|
|
|
|
may_reuse = rxrpc_may_reuse_conn(conn);
|
|
|
|
/* If a client call was exposed to the world, we save the result for
|
|
* retransmission.
|
|
*
|
|
* We use a barrier here so that the call number and abort code can be
|
|
* read without needing to take a lock.
|
|
*
|
|
* TODO: Make the incoming packet handler check this and handle
|
|
* terminal retransmission without requiring access to the call.
|
|
*/
|
|
if (test_bit(RXRPC_CALL_EXPOSED, &call->flags)) {
|
|
_debug("exposed %u,%u", call->call_id, call->abort_code);
|
|
__rxrpc_disconnect_call(conn, call);
|
|
|
|
if (test_and_clear_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags)) {
|
|
trace_rxrpc_client(conn, channel, rxrpc_client_to_active);
|
|
bundle->try_upgrade = false;
|
|
if (may_reuse)
|
|
rxrpc_activate_channels_locked(bundle);
|
|
}
|
|
|
|
}
|
|
|
|
/* See if we can pass the channel directly to another call. */
|
|
if (may_reuse && !list_empty(&bundle->waiting_calls)) {
|
|
trace_rxrpc_client(conn, channel, rxrpc_client_chan_pass);
|
|
rxrpc_activate_one_channel(conn, channel);
|
|
goto out;
|
|
}
|
|
|
|
/* Schedule the final ACK to be transmitted in a short while so that it
|
|
* can be skipped if we find a follow-on call. The first DATA packet
|
|
* of the follow on call will implicitly ACK this call.
|
|
*/
|
|
if (call->completion == RXRPC_CALL_SUCCEEDED &&
|
|
test_bit(RXRPC_CALL_EXPOSED, &call->flags)) {
|
|
unsigned long final_ack_at = jiffies + 2;
|
|
|
|
WRITE_ONCE(chan->final_ack_at, final_ack_at);
|
|
smp_wmb(); /* vs rxrpc_process_delayed_final_acks() */
|
|
set_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags);
|
|
rxrpc_reduce_conn_timer(conn, final_ack_at);
|
|
}
|
|
|
|
/* Deactivate the channel. */
|
|
rcu_assign_pointer(chan->call, NULL);
|
|
set_bit(conn->bundle_shift + channel, &conn->bundle->avail_chans);
|
|
conn->act_chans &= ~(1 << channel);
|
|
|
|
/* If no channels remain active, then put the connection on the idle
|
|
* list for a short while. Give it a ref to stop it going away if it
|
|
* becomes unbundled.
|
|
*/
|
|
if (!conn->act_chans) {
|
|
trace_rxrpc_client(conn, channel, rxrpc_client_to_idle);
|
|
conn->idle_timestamp = jiffies;
|
|
|
|
rxrpc_get_connection(conn);
|
|
spin_lock(&rxnet->client_conn_cache_lock);
|
|
list_move_tail(&conn->cache_link, &rxnet->idle_client_conns);
|
|
spin_unlock(&rxnet->client_conn_cache_lock);
|
|
|
|
rxrpc_set_client_reap_timer(rxnet);
|
|
}
|
|
|
|
out:
|
|
spin_unlock(&bundle->channel_lock);
|
|
_leave("");
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Remove a connection from a bundle.
|
|
*/
|
|
static void rxrpc_unbundle_conn(struct rxrpc_connection *conn)
|
|
{
|
|
struct rxrpc_bundle *bundle = conn->bundle;
|
|
struct rxrpc_local *local = bundle->params.local;
|
|
unsigned int bindex;
|
|
bool need_drop = false, need_put = false;
|
|
int i;
|
|
|
|
_enter("C=%x", conn->debug_id);
|
|
|
|
if (conn->flags & RXRPC_CONN_FINAL_ACK_MASK)
|
|
rxrpc_process_delayed_final_acks(conn, true);
|
|
|
|
spin_lock(&bundle->channel_lock);
|
|
bindex = conn->bundle_shift / RXRPC_MAXCALLS;
|
|
if (bundle->conns[bindex] == conn) {
|
|
_debug("clear slot %u", bindex);
|
|
bundle->conns[bindex] = NULL;
|
|
for (i = 0; i < RXRPC_MAXCALLS; i++)
|
|
clear_bit(conn->bundle_shift + i, &bundle->avail_chans);
|
|
need_drop = true;
|
|
}
|
|
spin_unlock(&bundle->channel_lock);
|
|
|
|
/* If there are no more connections, remove the bundle */
|
|
if (!bundle->avail_chans) {
|
|
_debug("maybe unbundle");
|
|
spin_lock(&local->client_bundles_lock);
|
|
|
|
for (i = 0; i < ARRAY_SIZE(bundle->conns); i++)
|
|
if (bundle->conns[i])
|
|
break;
|
|
if (i == ARRAY_SIZE(bundle->conns) && !bundle->params.exclusive) {
|
|
_debug("erase bundle");
|
|
rb_erase(&bundle->local_node, &local->client_bundles);
|
|
need_put = true;
|
|
}
|
|
|
|
spin_unlock(&local->client_bundles_lock);
|
|
if (need_put)
|
|
rxrpc_put_bundle(bundle);
|
|
}
|
|
|
|
if (need_drop)
|
|
rxrpc_put_connection(conn);
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* Clean up a dead client connection.
|
|
*/
|
|
static void rxrpc_kill_client_conn(struct rxrpc_connection *conn)
|
|
{
|
|
struct rxrpc_local *local = conn->params.local;
|
|
struct rxrpc_net *rxnet = local->rxnet;
|
|
|
|
_enter("C=%x", conn->debug_id);
|
|
|
|
trace_rxrpc_client(conn, -1, rxrpc_client_cleanup);
|
|
atomic_dec(&rxnet->nr_client_conns);
|
|
|
|
rxrpc_put_client_connection_id(conn);
|
|
rxrpc_kill_connection(conn);
|
|
}
|
|
|
|
/*
|
|
* Clean up a dead client connections.
|
|
*/
|
|
void rxrpc_put_client_conn(struct rxrpc_connection *conn)
|
|
{
|
|
const void *here = __builtin_return_address(0);
|
|
unsigned int debug_id = conn->debug_id;
|
|
int n;
|
|
|
|
n = atomic_dec_return(&conn->usage);
|
|
trace_rxrpc_conn(debug_id, rxrpc_conn_put_client, n, here);
|
|
if (n <= 0) {
|
|
ASSERTCMP(n, >=, 0);
|
|
rxrpc_kill_client_conn(conn);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Discard expired client connections from the idle list. Each conn in the
|
|
* idle list has been exposed and holds an extra ref because of that.
|
|
*
|
|
* This may be called from conn setup or from a work item so cannot be
|
|
* considered non-reentrant.
|
|
*/
|
|
void rxrpc_discard_expired_client_conns(struct work_struct *work)
|
|
{
|
|
struct rxrpc_connection *conn;
|
|
struct rxrpc_net *rxnet =
|
|
container_of(work, struct rxrpc_net, client_conn_reaper);
|
|
unsigned long expiry, conn_expires_at, now;
|
|
unsigned int nr_conns;
|
|
|
|
_enter("");
|
|
|
|
if (list_empty(&rxnet->idle_client_conns)) {
|
|
_leave(" [empty]");
|
|
return;
|
|
}
|
|
|
|
/* Don't double up on the discarding */
|
|
if (!spin_trylock(&rxnet->client_conn_discard_lock)) {
|
|
_leave(" [already]");
|
|
return;
|
|
}
|
|
|
|
/* We keep an estimate of what the number of conns ought to be after
|
|
* we've discarded some so that we don't overdo the discarding.
|
|
*/
|
|
nr_conns = atomic_read(&rxnet->nr_client_conns);
|
|
|
|
next:
|
|
spin_lock(&rxnet->client_conn_cache_lock);
|
|
|
|
if (list_empty(&rxnet->idle_client_conns))
|
|
goto out;
|
|
|
|
conn = list_entry(rxnet->idle_client_conns.next,
|
|
struct rxrpc_connection, cache_link);
|
|
|
|
if (!rxnet->kill_all_client_conns) {
|
|
/* If the number of connections is over the reap limit, we
|
|
* expedite discard by reducing the expiry timeout. We must,
|
|
* however, have at least a short grace period to be able to do
|
|
* final-ACK or ABORT retransmission.
|
|
*/
|
|
expiry = rxrpc_conn_idle_client_expiry;
|
|
if (nr_conns > rxrpc_reap_client_connections)
|
|
expiry = rxrpc_conn_idle_client_fast_expiry;
|
|
if (conn->params.local->service_closed)
|
|
expiry = rxrpc_closed_conn_expiry * HZ;
|
|
|
|
conn_expires_at = conn->idle_timestamp + expiry;
|
|
|
|
now = READ_ONCE(jiffies);
|
|
if (time_after(conn_expires_at, now))
|
|
goto not_yet_expired;
|
|
}
|
|
|
|
trace_rxrpc_client(conn, -1, rxrpc_client_discard);
|
|
list_del_init(&conn->cache_link);
|
|
|
|
spin_unlock(&rxnet->client_conn_cache_lock);
|
|
|
|
rxrpc_unbundle_conn(conn);
|
|
rxrpc_put_connection(conn); /* Drop the ->cache_link ref */
|
|
|
|
nr_conns--;
|
|
goto next;
|
|
|
|
not_yet_expired:
|
|
/* The connection at the front of the queue hasn't yet expired, so
|
|
* schedule the work item for that point if we discarded something.
|
|
*
|
|
* We don't worry if the work item is already scheduled - it can look
|
|
* after rescheduling itself at a later time. We could cancel it, but
|
|
* then things get messier.
|
|
*/
|
|
_debug("not yet");
|
|
if (!rxnet->kill_all_client_conns)
|
|
timer_reduce(&rxnet->client_conn_reap_timer, conn_expires_at);
|
|
|
|
out:
|
|
spin_unlock(&rxnet->client_conn_cache_lock);
|
|
spin_unlock(&rxnet->client_conn_discard_lock);
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* Preemptively destroy all the client connection records rather than waiting
|
|
* for them to time out
|
|
*/
|
|
void rxrpc_destroy_all_client_connections(struct rxrpc_net *rxnet)
|
|
{
|
|
_enter("");
|
|
|
|
spin_lock(&rxnet->client_conn_cache_lock);
|
|
rxnet->kill_all_client_conns = true;
|
|
spin_unlock(&rxnet->client_conn_cache_lock);
|
|
|
|
del_timer_sync(&rxnet->client_conn_reap_timer);
|
|
|
|
if (!rxrpc_queue_work(&rxnet->client_conn_reaper))
|
|
_debug("destroy: queue failed");
|
|
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* Clean up the client connections on a local endpoint.
|
|
*/
|
|
void rxrpc_clean_up_local_conns(struct rxrpc_local *local)
|
|
{
|
|
struct rxrpc_connection *conn, *tmp;
|
|
struct rxrpc_net *rxnet = local->rxnet;
|
|
LIST_HEAD(graveyard);
|
|
|
|
_enter("");
|
|
|
|
spin_lock(&rxnet->client_conn_cache_lock);
|
|
|
|
list_for_each_entry_safe(conn, tmp, &rxnet->idle_client_conns,
|
|
cache_link) {
|
|
if (conn->params.local == local) {
|
|
trace_rxrpc_client(conn, -1, rxrpc_client_discard);
|
|
list_move(&conn->cache_link, &graveyard);
|
|
}
|
|
}
|
|
|
|
spin_unlock(&rxnet->client_conn_cache_lock);
|
|
|
|
while (!list_empty(&graveyard)) {
|
|
conn = list_entry(graveyard.next,
|
|
struct rxrpc_connection, cache_link);
|
|
list_del_init(&conn->cache_link);
|
|
rxrpc_unbundle_conn(conn);
|
|
rxrpc_put_connection(conn);
|
|
}
|
|
|
|
_leave(" [culled]");
|
|
}
|