remarkable-linux/net/rxrpc/net_ns.c
David Howells 1392633baf rxrpc: Fix service endpoint expiry
[ Upstream commit f859ab6187 ]

RxRPC service endpoints expire like they're supposed to by the following
means:

 (1) Mark dead rxrpc_net structs (with ->live) rather than twiddling the
     global service conn timeout, otherwise the first rxrpc_net struct to
     die will cause connections on all others to expire immediately from
     then on.

 (2) Mark local service endpoints for which the socket has been closed
     (->service_closed) so that the expiration timeout can be much
     shortened for service and client connections going through that
     endpoint.

 (3) rxrpc_put_service_conn() needs to schedule the reaper when the usage
     count reaches 1, not 0, as idle conns have a 1 count.

 (4) The accumulator for the earliest time we might want to schedule for
     should be initialised to jiffies + MAX_JIFFY_OFFSET, not ULONG_MAX as
     the comparison functions use signed arithmetic.

 (5) Simplify the expiration handling, adding the expiration value to the
     idle timestamp each time rather than keeping track of the time in the
     past before which the idle timestamp must go to be expired.  This is
     much easier to read.

 (6) Ignore the timeouts if the net namespace is dead.

 (7) Restart the service reaper work item rather the client reaper.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-03 17:39:01 +01:00

88 lines
2.3 KiB
C

/* rxrpc network namespace handling.
*
* Copyright (C) 2017 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#include <linux/proc_fs.h>
#include "ar-internal.h"
unsigned int rxrpc_net_id;
/*
* Initialise a per-network namespace record.
*/
static __net_init int rxrpc_init_net(struct net *net)
{
struct rxrpc_net *rxnet = rxrpc_net(net);
int ret;
rxnet->live = true;
get_random_bytes(&rxnet->epoch, sizeof(rxnet->epoch));
rxnet->epoch |= RXRPC_RANDOM_EPOCH;
INIT_LIST_HEAD(&rxnet->calls);
rwlock_init(&rxnet->call_lock);
INIT_LIST_HEAD(&rxnet->conn_proc_list);
INIT_LIST_HEAD(&rxnet->service_conns);
rwlock_init(&rxnet->conn_lock);
INIT_DELAYED_WORK(&rxnet->service_conn_reaper,
rxrpc_service_connection_reaper);
rxnet->nr_client_conns = 0;
rxnet->nr_active_client_conns = 0;
rxnet->kill_all_client_conns = false;
spin_lock_init(&rxnet->client_conn_cache_lock);
spin_lock_init(&rxnet->client_conn_discard_lock);
INIT_LIST_HEAD(&rxnet->waiting_client_conns);
INIT_LIST_HEAD(&rxnet->active_client_conns);
INIT_LIST_HEAD(&rxnet->idle_client_conns);
INIT_DELAYED_WORK(&rxnet->client_conn_reaper,
rxrpc_discard_expired_client_conns);
INIT_LIST_HEAD(&rxnet->local_endpoints);
mutex_init(&rxnet->local_mutex);
hash_init(rxnet->peer_hash);
spin_lock_init(&rxnet->peer_hash_lock);
ret = -ENOMEM;
rxnet->proc_net = proc_net_mkdir(net, "rxrpc", net->proc_net);
if (!rxnet->proc_net)
goto err_proc;
proc_create("calls", 0444, rxnet->proc_net, &rxrpc_call_seq_fops);
proc_create("conns", 0444, rxnet->proc_net, &rxrpc_connection_seq_fops);
return 0;
err_proc:
rxnet->live = false;
return ret;
}
/*
* Clean up a per-network namespace record.
*/
static __net_exit void rxrpc_exit_net(struct net *net)
{
struct rxrpc_net *rxnet = rxrpc_net(net);
rxnet->live = false;
rxrpc_destroy_all_calls(rxnet);
rxrpc_destroy_all_connections(rxnet);
rxrpc_destroy_all_locals(rxnet);
proc_remove(rxnet->proc_net);
}
struct pernet_operations rxrpc_net_ops = {
.init = rxrpc_init_net,
.exit = rxrpc_exit_net,
.id = &rxrpc_net_id,
.size = sizeof(struct rxrpc_net),
};