mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 09:19:51 +00:00
![Denis V. Lunev](/assets/img/avatar_default.png)
Needed to propagate it down to the ip_route_output_flow. Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
316 lines
7.5 KiB
C
316 lines
7.5 KiB
C
/* RxRPC remote transport endpoint management
|
|
*
|
|
* Copyright (C) 2007 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 License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/net.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/udp.h>
|
|
#include <linux/in.h>
|
|
#include <linux/in6.h>
|
|
#include <linux/icmp.h>
|
|
#include <net/sock.h>
|
|
#include <net/af_rxrpc.h>
|
|
#include <net/ip.h>
|
|
#include <net/route.h>
|
|
#include "ar-internal.h"
|
|
|
|
static LIST_HEAD(rxrpc_peers);
|
|
static DEFINE_RWLOCK(rxrpc_peer_lock);
|
|
static DECLARE_WAIT_QUEUE_HEAD(rxrpc_peer_wq);
|
|
|
|
static void rxrpc_destroy_peer(struct work_struct *work);
|
|
|
|
/*
|
|
* assess the MTU size for the network interface through which this peer is
|
|
* reached
|
|
*/
|
|
static void rxrpc_assess_MTU_size(struct rxrpc_peer *peer)
|
|
{
|
|
struct rtable *rt;
|
|
struct flowi fl;
|
|
int ret;
|
|
|
|
peer->if_mtu = 1500;
|
|
|
|
memset(&fl, 0, sizeof(fl));
|
|
|
|
switch (peer->srx.transport.family) {
|
|
case AF_INET:
|
|
fl.oif = 0;
|
|
fl.proto = IPPROTO_UDP,
|
|
fl.nl_u.ip4_u.saddr = 0;
|
|
fl.nl_u.ip4_u.daddr = peer->srx.transport.sin.sin_addr.s_addr;
|
|
fl.nl_u.ip4_u.tos = 0;
|
|
/* assume AFS.CM talking to AFS.FS */
|
|
fl.uli_u.ports.sport = htons(7001);
|
|
fl.uli_u.ports.dport = htons(7000);
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
|
|
ret = ip_route_output_key(&init_net, &rt, &fl);
|
|
if (ret < 0) {
|
|
_leave(" [route err %d]", ret);
|
|
return;
|
|
}
|
|
|
|
peer->if_mtu = dst_mtu(&rt->u.dst);
|
|
dst_release(&rt->u.dst);
|
|
|
|
_leave(" [if_mtu %u]", peer->if_mtu);
|
|
}
|
|
|
|
/*
|
|
* allocate a new peer
|
|
*/
|
|
static struct rxrpc_peer *rxrpc_alloc_peer(struct sockaddr_rxrpc *srx,
|
|
gfp_t gfp)
|
|
{
|
|
struct rxrpc_peer *peer;
|
|
|
|
_enter("");
|
|
|
|
peer = kzalloc(sizeof(struct rxrpc_peer), gfp);
|
|
if (peer) {
|
|
INIT_WORK(&peer->destroyer, &rxrpc_destroy_peer);
|
|
INIT_LIST_HEAD(&peer->link);
|
|
INIT_LIST_HEAD(&peer->error_targets);
|
|
spin_lock_init(&peer->lock);
|
|
atomic_set(&peer->usage, 1);
|
|
peer->debug_id = atomic_inc_return(&rxrpc_debug_id);
|
|
memcpy(&peer->srx, srx, sizeof(*srx));
|
|
|
|
rxrpc_assess_MTU_size(peer);
|
|
peer->mtu = peer->if_mtu;
|
|
|
|
if (srx->transport.family == AF_INET) {
|
|
peer->hdrsize = sizeof(struct iphdr);
|
|
switch (srx->transport_type) {
|
|
case SOCK_DGRAM:
|
|
peer->hdrsize += sizeof(struct udphdr);
|
|
break;
|
|
default:
|
|
BUG();
|
|
break;
|
|
}
|
|
} else {
|
|
BUG();
|
|
}
|
|
|
|
peer->hdrsize += sizeof(struct rxrpc_header);
|
|
peer->maxdata = peer->mtu - peer->hdrsize;
|
|
}
|
|
|
|
_leave(" = %p", peer);
|
|
return peer;
|
|
}
|
|
|
|
/*
|
|
* obtain a remote transport endpoint for the specified address
|
|
*/
|
|
struct rxrpc_peer *rxrpc_get_peer(struct sockaddr_rxrpc *srx, gfp_t gfp)
|
|
{
|
|
struct rxrpc_peer *peer, *candidate;
|
|
const char *new = "old";
|
|
int usage;
|
|
|
|
_enter("{%d,%d,%u.%u.%u.%u+%hu}",
|
|
srx->transport_type,
|
|
srx->transport_len,
|
|
NIPQUAD(srx->transport.sin.sin_addr),
|
|
ntohs(srx->transport.sin.sin_port));
|
|
|
|
/* search the peer list first */
|
|
read_lock_bh(&rxrpc_peer_lock);
|
|
list_for_each_entry(peer, &rxrpc_peers, link) {
|
|
_debug("check PEER %d { u=%d t=%d l=%d }",
|
|
peer->debug_id,
|
|
atomic_read(&peer->usage),
|
|
peer->srx.transport_type,
|
|
peer->srx.transport_len);
|
|
|
|
if (atomic_read(&peer->usage) > 0 &&
|
|
peer->srx.transport_type == srx->transport_type &&
|
|
peer->srx.transport_len == srx->transport_len &&
|
|
memcmp(&peer->srx.transport,
|
|
&srx->transport,
|
|
srx->transport_len) == 0)
|
|
goto found_extant_peer;
|
|
}
|
|
read_unlock_bh(&rxrpc_peer_lock);
|
|
|
|
/* not yet present - create a candidate for a new record and then
|
|
* redo the search */
|
|
candidate = rxrpc_alloc_peer(srx, gfp);
|
|
if (!candidate) {
|
|
_leave(" = -ENOMEM");
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
write_lock_bh(&rxrpc_peer_lock);
|
|
|
|
list_for_each_entry(peer, &rxrpc_peers, link) {
|
|
if (atomic_read(&peer->usage) > 0 &&
|
|
peer->srx.transport_type == srx->transport_type &&
|
|
peer->srx.transport_len == srx->transport_len &&
|
|
memcmp(&peer->srx.transport,
|
|
&srx->transport,
|
|
srx->transport_len) == 0)
|
|
goto found_extant_second;
|
|
}
|
|
|
|
/* we can now add the new candidate to the list */
|
|
peer = candidate;
|
|
candidate = NULL;
|
|
|
|
list_add_tail(&peer->link, &rxrpc_peers);
|
|
write_unlock_bh(&rxrpc_peer_lock);
|
|
new = "new";
|
|
|
|
success:
|
|
_net("PEER %s %d {%d,%u,%u.%u.%u.%u+%hu}",
|
|
new,
|
|
peer->debug_id,
|
|
peer->srx.transport_type,
|
|
peer->srx.transport.family,
|
|
NIPQUAD(peer->srx.transport.sin.sin_addr),
|
|
ntohs(peer->srx.transport.sin.sin_port));
|
|
|
|
_leave(" = %p {u=%d}", peer, atomic_read(&peer->usage));
|
|
return peer;
|
|
|
|
/* we found the peer in the list immediately */
|
|
found_extant_peer:
|
|
usage = atomic_inc_return(&peer->usage);
|
|
read_unlock_bh(&rxrpc_peer_lock);
|
|
goto success;
|
|
|
|
/* we found the peer on the second time through the list */
|
|
found_extant_second:
|
|
usage = atomic_inc_return(&peer->usage);
|
|
write_unlock_bh(&rxrpc_peer_lock);
|
|
kfree(candidate);
|
|
goto success;
|
|
}
|
|
|
|
/*
|
|
* find the peer associated with a packet
|
|
*/
|
|
struct rxrpc_peer *rxrpc_find_peer(struct rxrpc_local *local,
|
|
__be32 addr, __be16 port)
|
|
{
|
|
struct rxrpc_peer *peer;
|
|
|
|
_enter("");
|
|
|
|
/* search the peer list */
|
|
read_lock_bh(&rxrpc_peer_lock);
|
|
|
|
if (local->srx.transport.family == AF_INET &&
|
|
local->srx.transport_type == SOCK_DGRAM
|
|
) {
|
|
list_for_each_entry(peer, &rxrpc_peers, link) {
|
|
if (atomic_read(&peer->usage) > 0 &&
|
|
peer->srx.transport_type == SOCK_DGRAM &&
|
|
peer->srx.transport.family == AF_INET &&
|
|
peer->srx.transport.sin.sin_port == port &&
|
|
peer->srx.transport.sin.sin_addr.s_addr == addr)
|
|
goto found_UDP_peer;
|
|
}
|
|
|
|
goto new_UDP_peer;
|
|
}
|
|
|
|
read_unlock_bh(&rxrpc_peer_lock);
|
|
_leave(" = -EAFNOSUPPORT");
|
|
return ERR_PTR(-EAFNOSUPPORT);
|
|
|
|
found_UDP_peer:
|
|
_net("Rx UDP DGRAM from peer %d", peer->debug_id);
|
|
atomic_inc(&peer->usage);
|
|
read_unlock_bh(&rxrpc_peer_lock);
|
|
_leave(" = %p", peer);
|
|
return peer;
|
|
|
|
new_UDP_peer:
|
|
_net("Rx UDP DGRAM from NEW peer %d", peer->debug_id);
|
|
read_unlock_bh(&rxrpc_peer_lock);
|
|
_leave(" = -EBUSY [new]");
|
|
return ERR_PTR(-EBUSY);
|
|
}
|
|
|
|
/*
|
|
* release a remote transport endpoint
|
|
*/
|
|
void rxrpc_put_peer(struct rxrpc_peer *peer)
|
|
{
|
|
_enter("%p{u=%d}", peer, atomic_read(&peer->usage));
|
|
|
|
ASSERTCMP(atomic_read(&peer->usage), >, 0);
|
|
|
|
if (likely(!atomic_dec_and_test(&peer->usage))) {
|
|
_leave(" [in use]");
|
|
return;
|
|
}
|
|
|
|
rxrpc_queue_work(&peer->destroyer);
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* destroy a remote transport endpoint
|
|
*/
|
|
static void rxrpc_destroy_peer(struct work_struct *work)
|
|
{
|
|
struct rxrpc_peer *peer =
|
|
container_of(work, struct rxrpc_peer, destroyer);
|
|
|
|
_enter("%p{%d}", peer, atomic_read(&peer->usage));
|
|
|
|
write_lock_bh(&rxrpc_peer_lock);
|
|
list_del(&peer->link);
|
|
write_unlock_bh(&rxrpc_peer_lock);
|
|
|
|
_net("DESTROY PEER %d", peer->debug_id);
|
|
kfree(peer);
|
|
|
|
if (list_empty(&rxrpc_peers))
|
|
wake_up_all(&rxrpc_peer_wq);
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* preemptively destroy all the peer records from a transport endpoint rather
|
|
* than waiting for them to time out
|
|
*/
|
|
void __exit rxrpc_destroy_all_peers(void)
|
|
{
|
|
DECLARE_WAITQUEUE(myself,current);
|
|
|
|
_enter("");
|
|
|
|
/* we simply have to wait for them to go away */
|
|
if (!list_empty(&rxrpc_peers)) {
|
|
set_current_state(TASK_UNINTERRUPTIBLE);
|
|
add_wait_queue(&rxrpc_peer_wq, &myself);
|
|
|
|
while (!list_empty(&rxrpc_peers)) {
|
|
schedule();
|
|
set_current_state(TASK_UNINTERRUPTIBLE);
|
|
}
|
|
|
|
remove_wait_queue(&rxrpc_peer_wq, &myself);
|
|
set_current_state(TASK_RUNNING);
|
|
}
|
|
|
|
_leave("");
|
|
}
|