- 根目录:
- net
- rxrpc
- ar-connection.c
/* RxRPC virtual connection handler
*
* 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/slab.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/crypto.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include "ar-internal.h"
static void rxrpc_connection_reaper(struct work_struct *work);
LIST_HEAD(rxrpc_connections);
DEFINE_RWLOCK(rxrpc_connection_lock);
static unsigned long rxrpc_connection_timeout = 10 * 60;
static DECLARE_DELAYED_WORK(rxrpc_connection_reap, rxrpc_connection_reaper);
/*
* allocate a new client connection bundle
*/
static struct rxrpc_conn_bundle *rxrpc_alloc_bundle(gfp_t gfp)
{
struct rxrpc_conn_bundle *bundle;
_enter("");
bundle = kzalloc(sizeof(struct rxrpc_conn_bundle), gfp);
if (bundle) {
INIT_LIST_HEAD(&bundle->unused_conns);
INIT_LIST_HEAD(&bundle->avail_conns);
INIT_LIST_HEAD(&bundle->busy_conns);
init_waitqueue_head(&bundle->chanwait);
atomic_set(&bundle->usage, 1);
}
_leave(" = %p", bundle);
return bundle;
}
/*
* compare bundle parameters with what we're looking for
* - return -ve, 0 or +ve
*/
static inline
int rxrpc_cmp_bundle(const struct rxrpc_conn_bundle *bundle,
struct key *key, __be16 service_id)
{
return (bundle->service_id - service_id) ?:
((unsigned long) bundle->key - (unsigned long) key);
}
/*
* get bundle of client connections that a client socket can make use of
*/
struct rxrpc_conn_bundle *rxrpc_get_bundle(struct rxrpc_sock *rx,
struct rxrpc_transport *trans,
struct key *key,
__be16 service_id,
gfp_t gfp)
{
struct rxrpc_conn_bundle *bundle, *candidate;
struct rb_node *p, *parent, **pp;
_enter("%p{%x},%x,%hx,",
rx, key_serial(key), trans->debug_id, ntohs(service_id));
if (rx->trans == trans && rx->bundle) {
atomic_inc(&rx->bundle->usage);
return rx->bundle;
}
/* search the extant bundles first for one that matches the specified
* user ID */
spin_lock(&trans->client_lock);
p = trans->bundles.rb_node;
while (p) {
bundle = rb_entry(p, struct rxrpc_conn_bundle, node);
if (rxrpc_cmp_bundle(bundle, key, service_id) < 0)
p = p->rb_left;
else if (rxrpc_cmp_bundle(bundle, key, service_id) > 0)
p = p->rb_right;
else
goto found_extant_bundle;
}
spin_unlock(&trans->client_lock);
/* not yet present - create a candidate for a new record and then
* redo the search */
candidate = rxrpc_alloc_bundle(gfp);
if (!candidate) {
_leave(" = -ENOMEM");
return ERR_PTR(-ENOMEM);
}
candidate->key = key_get(key);
candidate->service_id = service_id;
spin_lock(&trans->client_lock);
pp = &trans->bundles.rb_node;
parent = NULL;
while (*pp) {
parent = *pp;
bundle = rb_entry(parent, struct rxrpc_conn_bundle, node);
if (rxrpc_cmp_bundle(bundle, key, service_id) < 0)
pp = &(*pp)->rb_left;
else if (rxrpc_cmp_bundle(bundle, key, service_id) > 0)
pp = &(*pp)->rb_right;
else
goto found_extant_second;
}
/* second search also failed; add the new bundle */
bundle = candidate;
candidate = NULL;
rb_link_node(&bundle->node, parent, pp);
rb_insert_color(&bundle->node, &trans->bundles);
spin_unlock(&trans->client_lock);
_net("BUNDLE new on trans %d", trans->debug_id);
if (!rx->bundle && rx->sk.sk_state == RXRPC_CLIENT_CONNECTED) {
atomic_inc(&bundle->usage);
rx->bundle = bundle;
}
_leave(" = %p [new]", bundle);
return bundle;
/* we found the bundle in the list immediately */
found_extant_bundle:
atomic_inc(&bundle->usage);
spin_unlock(&trans->client_lock);
_net("BUNDLE old on trans %d", trans->debug_id);
if (!rx->bundle && rx->sk.sk_state == RXRPC_CLIENT_CONNECTED) {
atomic_inc(&bundle->usage);
rx->bundle = bundle;
}
_leave(" = %p [extant %d]", bundle, atomic_read(&bundle->usage));
return bundle;
/* we found the bundle on the second time through the list */
found_extant_second:
atomic_inc(&bundle->usage);
spin_unlock(&trans->client_lock);
kfree(candidate);
_net("BUNDLE old2 on trans %d", trans->debug_id);
if (!rx->bundle && rx->sk.sk_state == RXRPC_CLIENT_CONNECTED) {
atomic_inc(&bundle->usage);
rx->bundle = bundle;
}
_leave(" = %p [second %d]", bundle, atomic_read(&bundle->usage));
return bundle;
}
/*
* release a bundle
*/
void rxrpc_put_bundle(struct rxrpc_transport *trans,
struct rxrpc_conn_bundle *bundle)
{
_enter("%p,%p{%d}",trans, bundle, atomic_read(&bundle->usage));
if (atomic_dec_and_lock(&bundle->usage, &trans->client_lock)) {
_debug("Destroy bundle");
rb_erase(&bundle->node, &trans->bundles);
spin_unlock(&trans->client_lock);
ASSERT(list_empty(&bundle->unused_conns));
ASSERT(list_empty(&bundle->avail_conns));
ASSERT(list_empty(&bundle->busy_conns));
ASSERTCMP(bundle->num_conns, ==, 0);
key_put(bundle->key);
kfree(bundle);
}
_leave("");
}
/*
* allocate a new connection
*/
static struct rxrpc_connection *rxrpc_alloc_connection(gfp_t gfp)
{
struct rxrpc_connection *conn;
_enter("");
conn = kzalloc(sizeof(struct rxrpc_connection), gfp);
if (conn) {
INIT_WORK(&conn->processor, &rxrpc_process_connection);
INIT_LIST_HEAD(&conn->bundle_link);
conn->calls = RB_ROOT;
skb_queue_head_init(&conn->rx_queue);
rwlock_init(&conn->lock);
spin_lock_init(&conn->state_lock);
atomic_set(&conn->usage, 1);
conn->debug_id = atomic_inc_return(&rxrpc_debug_id);
conn->avail_calls = RXRPC_MAXCALLS;
conn->size_align = 4;
conn->header_size = sizeof(struct rxrpc_header);
}
_leave(" = %p{%d}", conn, conn ? conn->debug_id : 0);
return conn;
}
/*
* assign a connection ID to a connection and add it to the transport's
* connection lookup tree
* - called with transport client lock held
*/
static void rxrpc_assign_connection_id(struct rxrpc_connection *conn)
{
struct rxrpc_connection *xconn;
struct rb_node *parent, **p;
__be32 epoch;
u32 real_conn_id;
_enter("");
epoch = conn->epoch;
write_lock_bh(&conn->trans->conn_lock);
conn->trans->conn_idcounter += RXRPC_CID_INC;
if (conn->trans->conn_idcounter < RXRPC_CID_INC)
conn->trans->conn_idcounter = RXRPC_CID_INC;
real_conn_id = conn->trans->conn_idcounter;
attempt_insertion:
parent = NULL;
p = &conn->trans->client_conns.rb_node;
while (*p) {
parent = *p;
xconn = rb_entry(parent, struct rxrpc_connection, node);
if (epoch < xconn->epoch)
p = &(*p)->rb_left;
else if (epoch > xconn->epoch)
p = &(*p)->rb_right;
else if (real_conn_id < xconn->real_conn_id)
p = &(*p)->rb_left;
else if (real_conn_id > xconn->real_conn_id)
p = &(*p)->rb_right;
else
goto id_exists;
}
/* we've found a suitable hole - arrange for this connection to occupy
* it */
rb_link_node(&conn->node, parent, p);
rb_insert_color(&conn->node, &conn->trans->client_conns);
conn->real_conn_id = real_conn_id;
conn->cid = htonl(real_conn_id);
write_unlock_bh(&conn->trans->conn_lock);
_leave(" [CONNID %x CID %x]", real_conn_id, ntohl(conn->cid));
return;
/* we found a connection with the proposed ID - walk the tree from that
* point looking for the next unused ID */
id_exists:
for (;;) {
real_conn_id += RXRPC_CID_INC;
if (real_conn_id < RXRPC_CID_INC) {
real_conn_id = RXRPC_CID_INC;
conn->trans->conn_idcounter = real_conn_id;
goto attempt_insertion;
}
parent = rb_next(parent);
if (!parent)
goto attempt_insertion;
xconn = rb_entry(parent, struct rxrpc_connection, node);
if (epoch < xconn->epoch ||
real_conn_id < xconn->real_conn_id)
goto attempt_insertion;
}
}
/*
* add a call to a connection's call-by-ID tree
*/
static void rxrpc_add_call_ID_to_conn(struct rxrpc_connection *conn,
struct rxrpc_call *call)
{
struct rxrpc_call *xcall;
struct rb_node *parent, **p;
__be32 call_id;
write_lock_bh(&conn->lock);
call_id = call->call_id;
p = &conn->calls.rb_node;
parent = NULL;
while (*p) {
parent = *p;
xcall = rb_entry(parent, struct rxrpc_call, conn_node);
if (call_id < xcall->call_id)
p = &(*p)->rb_left;
else if (call_id > xcall->call_id)
p = &(*p)->rb_right;
else
BUG();
}
rb_link_node(&call->conn_node, parent, p);
rb_insert_color(&call->conn_node, &conn->calls);
write_unlock_bh(&conn->lock);
}
/*
* connect a call on an exclusive connection
*/
static int rxrpc_connect_exclusive(struct rxrpc_sock *rx,
struct rxrpc_transport *trans,
__be16 service_id,
struct rxrpc_call *call,
gfp_t gfp)
{
struct rxrpc_connection *conn;
int chan, ret;
_enter("");
conn = rx->conn;
if (!conn) {
/* not yet present - create a candidate for a new connection
* and then redo the check */
conn = rxrpc_alloc_connection(gfp);
if (!conn) {
_leave(" = -ENOMEM");
return -ENOMEM;
}
conn->trans = trans;
conn->bundle = NULL;
conn->service_id = service_id;
conn->epoch = rxrpc_epoch;
conn->in_clientflag = 0;
conn->out_clientflag = RXRPC_CLIENT_INITIATED;
conn->cid = 0;
conn->state = RXRPC_CONN_CLIENT;
conn->avail_calls = RXRPC_MAXCALLS - 1;
conn->security_level = rx->min_sec_level;
conn->key = key_get(rx->key);
ret = rxrpc_init_client_conn_security(conn);
if (ret < 0) {
key_put(conn->key);
kfree(conn);
_leave(" = %d [key]", ret);
return ret;
}
write_lock_bh(&rxrpc_connection_lock);
list_add_tail(&conn->link, &rxrpc_connections);
write_unlock_bh(&rxrpc_connection_lock);
spin_lock(&trans->client_lock);
atomic_inc(&trans->usage);
_net("CONNECT EXCL new %d on TRANS %d",
conn->debug_id, conn->trans->debug_id);
rxrpc_assign_connection_id(conn);
rx->conn = conn;
}
/* we've got a connection with a free channel and we can now attach the
* call to it
* - we're holding the transport's client lock
* - we're holding a reference on the connection
*/
for (chan = 0; chan < RXRPC_MAXCALLS; chan++)
if (!conn->channels[chan])
goto found_channel;
goto no_free_channels;
found_channel:
atomic_inc(&conn->usage);
conn->channels[chan] = call;
call->conn = conn;
call->channel = chan;
call->cid = conn->cid | htonl(chan);
call->call_id = htonl(++conn->call_counter);
_net("CONNECT client on conn %d chan %d as call %x",
conn->debug_id, chan, ntohl(call->call_id));
spin_unlock(&trans->client_lock);
rxrpc_add_call_ID_to_conn(conn, call);
_leave(" = 0");
return 0;
no_free_channels:
spin_unlock(&trans->client_lock);
_leave(" = -ENOSR");
return -ENOSR;
}
/*
* find a connection for a call
* - called in process context with IRQs enabled
*/
int rxrpc_connect_call(struct rxrpc_sock *rx,
struct rxrpc_transport *trans,
struct rxrpc_conn_bundle *bundle,
struct rxrpc_call *call,
gfp_t gfp)
{
struct rxrpc_connection *conn, *candidate;
int chan, ret;
DECLARE_WAITQUEUE(myself, current);
_enter("%p,%lx,", rx, call->user_call_ID);
if (test_bit(RXRPC_SOCK_EXCLUSIVE_CONN, &rx->flags))
return rxrpc_connect_exclusive(rx, trans, bundle->service_id,
call, gfp);
spin_lock(&trans->client_lock);
for (;;) {
/* see if the bundle has a call slot available */
if (!list_empty(&bundle->avail_conns)) {
_debug("avail");
conn = list_entry(bundle->avail_conns.next,
struct rxrpc_connection,
bundle_link);
if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
list_del_init(&conn->bundle_link);
bundle->num_conns--;
continue;
}
if (--conn->avail_calls == 0)
list_move(&conn->bundle_link,
&bundle->busy_conns);
ASSERTCMP(conn->avail_calls, <, RXRPC_MAXCALLS);
ASSERT(conn->channels[0] == NULL ||
conn->channels[1] == NULL ||
conn->channels[2] == NULL ||
conn->channels[3] == NULL);
atomic_inc(&conn->usage);
break;
}
if (!list_empty(&bundle->unused_conns)) {
_debug("unused");
conn = list_entry(bundle->unused_conns.next,
struct rxrpc_connection,
bundle_link);
if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
list_del_init(&conn->bundle_link);
bundle->num_conns--;
continue;
}
ASSERTCMP(conn->avail_calls, ==, RXRPC_MAXCALLS);
conn->avail_calls = RXRPC_MAXCALLS - 1;
ASSERT(conn->channels[0] == NULL &&
conn->channels[1] == NULL &&
conn->channels[2] == NULL &&
conn->channels[3] == NULL);
atomic_inc(&conn->usage);
list_move(&conn->bundle_link, &bundle->avail_conns);
break;
}
/* need to allocate a new connection */
_debug("get new conn [%d]", bundle->num_conns);
spin_unlock(&trans->client_lock);
if (signal_pending(current))
goto interrupted;
if (bundle->num_conns >= 20) {
_debug("too many conns");
if (!(gfp & __GFP_WAIT)) {
_leave(" = -EAGAIN");
return -EAGAIN;
}
add_wait_queue(&bundle->chanwait, &myself);
for (;;) {
set_current_state(TASK_INTERRUPTIBLE);
if (bundle->num_conns < 20 ||
!list_empty(&bundle->unused_conns) ||
!list_empty(&bundle->avail_conns))
break;
if (signal_pending(current))
goto interrupted_dequeue;
schedule();
}
remove_wait_queue(&bundle->chanwait, &myself);
__set_current_state(TASK_RUNNING);
spin_lock(&trans->client_lock);
continue;
}
/* not yet present - create a candidate for a new connection and then
* redo the check */
candidate = rxrpc_alloc_connection(gfp);
if (!candidate) {
_leave(" = -ENOMEM");
return -ENOMEM;
}
candidate->trans = trans;
candidate->bundle = bundle;
candidate->service_id = bundle->service_id;
candidate->epoch = rxrpc_epoch;
candidate->in_clientflag = 0;
candidate->out_clientflag = RXRPC_CLIENT_INITIATED;
candidate->cid = 0;
candidate->state = RXRPC_CONN_CLIENT;
candidate->avail_calls = RXRPC_MAXCALLS;
candidate->security_level = rx->min_sec_level;
candidate->key = key_get(bundle->key);
ret = rxrpc_init_client_conn_security(candidate);
if (ret < 0) {
key_put(candidate->key);
kfree(candidate);
_leave(" = %d [key]", ret);
return ret;
}
write_lock_bh(&rxrpc_connection_lock);
list_add_tail(&candidate->link, &rxrpc_connections);
write_unlock_bh(&rxrpc_connection_lock);
spin_lock(&trans->client_lock);
list_add(&candidate->bundle_link, &bundle->unused_conns);
bundle->num_conns++;
atomic_inc(&bundle->usage);
atomic_inc(&trans->usage);
_net("CONNECT new %d on TRANS %d",
candidate->debug_id, candidate->trans->debug_id);
rxrpc_assign_connection_id(candidate);
if (candidate->security)
candidate->security->prime_packet_security(candidate);
/* leave the candidate lurking in zombie mode attached to the
* bundle until we're ready for it */
rxrpc_put_connection(candidate);
candidate = NULL;
}
/* we've got a connection with a free channel and we can now attach the
* call to it
* - we're holding the transport's client lock
* - we're holding a reference on the connection
* - we're holding a reference on the bundle
*/
for (chan = 0; chan < RXRPC_MAXCALLS; chan++)
if (!conn->channels[chan])
goto found_channel;
ASSERT(conn->channels[0] == NULL ||
conn->channels[1] == NULL ||
conn->channels[2] == NULL ||
conn->channels[3] == NULL);
BUG();
found_channel:
conn->channels[chan] = call;
call->conn = conn;
call->channel = chan;
call->cid = conn->cid | htonl(chan);
call->call_id = htonl(++conn->call_counter);
_net("CONNECT client on conn %d chan %d as call %x",
conn->debug_id, chan, ntohl(call->call_id));
ASSERTCMP(conn->avail_calls, <, RXRPC_MAXCALLS);
spin_unlock(&trans->client_lock);
rxrpc_add_call_ID_to_conn(conn, call);
_leave(" = 0");
return 0;
interrupted_dequeue:
remove_wait_queue(&bundle->chanwait, &myself);
__set_current_state(TASK_RUNNING);
interrupted:
_leave(" = -ERESTARTSYS");
return -ERESTARTSYS;
}
/*
* get a record of an incoming connection
*/
struct rxrpc_connection *
rxrpc_incoming_connection(struct rxrpc_transport *trans,
struct rxrpc_header *hdr,
gfp_t gfp)
{
struct rxrpc_connection *conn, *candidate = NULL;
struct rb_node *p, **pp;
const char *new = "old";
__be32 epoch;
u32 conn_id;
_enter("");
ASSERT(hdr->flags & RXRPC_CLIENT_INITIATED);
epoch = hdr->epoch;
conn_id = ntohl(hdr->cid) & RXRPC_CIDMASK;
/* search the connection list first */
read_lock_bh(&trans->conn_lock);
p = trans->server_conns.rb_node;
while (p) {
conn = rb_entry(p, struct rxrpc_connection, node);
_debug("maybe %x", conn->real_conn_id);
if (epoch < conn->epoch)
p = p->rb_left;
else if (epoch > conn->epoch)
p = p->rb_right;
else if (conn_id < conn->real_conn_id)
p = p->rb_left;
else if (conn_id > conn->real_conn_id)
p = p->rb_right;
else
goto found_extant_connection;
}
read_unlock_bh(&trans->conn_lock);
/* not yet present - create a candidate for a new record and then
* redo the search */
candidate = rxrpc_alloc_connection(gfp);
if (!candidate) {
_leave(" = -ENOMEM");
return ERR_PTR(-ENOMEM);
}
candidate->trans = trans;
candidate->epoch = hdr->epoch;
candidate->cid = hdr->cid & cpu_to_be32(RXRPC_CIDMASK);
candidate->service_id = hdr->serviceId;
candidate->security_ix = hdr->securityIndex;
candidate->in_clientflag = RXRPC_CLIENT_INITIATED;
candidate->out_clientflag = 0;
candidate->real_conn_id = conn_id;
candidate->state = RXRPC_CONN_SERVER;
if (candidate->service_id)
candidate->state = RXRPC_CONN_SERVER_UNSECURED;
write_lock_bh(&trans->conn_lock);
pp = &trans->server_conns.rb_node;
p = NULL;
while (*pp) {
p = *pp;
conn = rb_entry(p, struct rxrpc_connection, node);
if (epoch < conn->epoch)
pp = &(*pp)->rb_left;
else if (epoch > conn->epoch)
pp = &(*pp)->rb_right;
else if (conn_id < conn->real_conn_id)
pp = &(*pp)->rb_left;
else if (conn_id > conn->real_conn_id)
pp = &(*pp)->rb_right;
else
goto found_extant_second;
}
/* we can now add the new candidate to the list */
conn = candidate;
candidate = NULL;
rb_link_node(&conn->node, p, pp);
rb_insert_color(&conn->node, &trans->server_conns);
atomic_inc(&conn->trans->usage);
write_unlock_bh(&trans->conn_lock);
write_lock_bh(&rxrpc_connection_lock);
list_add_tail(&conn->link, &rxrpc_connections);
write_unlock_bh(&rxrpc_connection_lock);
new = "new";
success:
_net("CONNECTION %s %d {%x}", new, conn->debug_id, conn->real_conn_id);
_leave(" = %p {u=%d}", conn, atomic_read(&conn->usage));
return conn;
/* we found the connection in the list immediately */
found_extant_connection:
if (hdr->securityIndex != conn->security_ix) {
read_unlock_bh(&trans->conn_lock);
goto security_mismatch;
}
atomic_inc(&conn->usage);
read_unlock_bh(&trans->conn_lock);
goto success;
/* we found the connection on the second time through the list */
found_extant_second:
if (hdr->securityIndex != conn->security_ix) {
write_unlock_bh(&trans->conn_lock);
goto security_mismatch;
}
atomic_inc(&conn->usage);
write_unlock_bh(&trans->conn_lock);
kfree(candidate);
goto success;
security_mismatch:
kfree(candidate);
_leave(" = -EKEYREJECTED");
return ERR_PTR(-EKEYREJECTED);
}
/*
* find a connection based on transport and RxRPC connection ID for an incoming
* packet
*/
struct rxrpc_connection *rxrpc_find_connection(struct rxrpc_transport *trans,
struct rxrpc_header *hdr)
{
struct rxrpc_connection *conn;
struct rb_node *p;
__be32 epoch;
u32 conn_id;
_enter(",{%x,%x}", ntohl(hdr->cid), hdr->flags);
read_lock_bh(&trans->conn_lock);
conn_id = ntohl(hdr->cid) & RXRPC_CIDMASK;
epoch = hdr->epoch;
if (hdr->flags & RXRPC_CLIENT_INITIATED)
p = trans->server_conns.rb_node;
else
p = trans->client_conns.rb_node;
while (p) {
conn = rb_entry(p, struct rxrpc_connection, node);
_debug("maybe %x", conn->real_conn_id);
if (epoch < conn->epoch)
p = p->rb_left;
else if (epoch > conn->epoch)
p = p->rb_right;
else if (conn_id < conn->real_conn_id)
p = p->rb_left;
else if (conn_id > conn->real_conn_id)
p = p->rb_right;
else
goto found;
}
read_unlock_bh(&trans->conn_lock);
_leave(" = NULL");
return NULL;
found:
atomic_inc(&conn->usage);
read_unlock_bh(&trans->conn_lock);
_leave(" = %p", conn);
return conn;
}
/*
* release a virtual connection
*/
void rxrpc_put_connection(struct rxrpc_connection *conn)
{
_enter("%p{u=%d,d=%d}",
conn, atomic_read(&conn->usage), conn->debug_id);
ASSERTCMP(atomic_read(&conn->usage), >, 0);
conn->put_time = get_seconds();
if (atomic_dec_and_test(&conn->usage)) {
_debug("zombie");
rxrpc_queue_delayed_work(&rxrpc_connection_reap, 0);
}
_leave("");
}
/*
* destroy a virtual connection
*/
static void rxrpc_destroy_connection(struct rxrpc_connection *conn)
{
_enter("%p{%d}", conn, atomic_read(&conn->usage));
ASSERTCMP(atomic_read(&conn->usage), ==, 0);
_net("DESTROY CONN %d", conn->debug_id);
if (conn->bundle)
rxrpc_put_bundle(conn->trans, conn->bundle);
ASSERT(RB_EMPTY_ROOT(&conn->calls));
rxrpc_purge_queue(&conn->rx_queue);
rxrpc_clear_conn_security(conn);
rxrpc_put_transport(conn->trans);
kfree(conn);
_leave("");
}
/*
* reap dead connections
*/
static void rxrpc_connection_reaper(struct work_struct *work)
{
struct rxrpc_connection *conn, *_p;
unsigned long now, earliest, reap_time;
LIST_HEAD(graveyard);
_enter("");
now = get_seconds();
earliest = ULONG_MAX;
write_lock_bh(&rxrpc_connection_lock);
list_for_each_entry_safe(conn, _p, &rxrpc_connections, link) {
_debug("reap CONN %d { u=%d,t=%ld }",
conn->debug_id, atomic_read(&conn->usage),
(long) now - (long) conn->put_time);
if (likely(atomic_read(&conn->usage) > 0))
continue;
spin_lock(&conn->trans->client_lock);
write_lock(&conn->trans->conn_lock);
reap_time = conn->put_time + rxrpc_connection_timeout;
if (atomic_read(&conn->usage) > 0) {
;
} else if (reap_time <= now) {
list_move_tail(&conn->link, &graveyard);
if (conn->out_clientflag)
rb_erase(&conn->node,
&conn->trans->client_conns);
else
rb_erase(&conn->node,
&conn->trans->server_conns);
if (conn->bundle) {
list_del_init(&conn->bundle_link);
conn->bundle->num_conns--;
}
} else if (reap_time < earliest) {
earliest = reap_time;
}
write_unlock(&conn->trans->conn_lock);
spin_unlock(&conn->trans->client_lock);
}
write_unlock_bh(&rxrpc_connection_lock);
if (earliest != ULONG_MAX) {
_debug("reschedule reaper %ld", (long) earliest - now);
ASSERTCMP(earliest, >, now);
rxrpc_queue_delayed_work(&rxrpc_connection_reap,
(earliest - now) * HZ);
}
/* then destroy all those pulled out */
while (!list_empty(&graveyard)) {
conn = list_entry(graveyard.next, struct rxrpc_connection,
link);
list_del_init(&conn->link);
ASSERTCMP(atomic_read(&conn->usage), ==, 0);
rxrpc_destroy_connection(conn);
}
_leave("");
}
/*
* preemptively destroy all the connection records rather than waiting for them
* to time out
*/
void __exit rxrpc_destroy_all_connections(void)
{
_enter("");
rxrpc_connection_timeout = 0;
cancel_delayed_work(&rxrpc_connection_reap);
rxrpc_queue_delayed_work(&rxrpc_connection_reap, 0);
_leave("");
}