linux/net/rxrpc/ar-connection.c
David Howells 0d12f8a402 rxrpc: Keep the skb private record of the Rx header in host byte order
Currently, a copy of the Rx packet header is copied into the the sk_buff
private data so that we can advance the pointer into the buffer,
potentially discarding the original.  At the moment, this copy is held in
network byte order, but this means we're doing a lot of unnecessary
translations.

The reasons it was done this way are that we need the values in network
byte order occasionally and we can use the copy, slightly modified, as part
of an iov array when sending an ack or an abort packet.

However, it seems more reasonable on review that it would be better kept in
host byte order and that we make up a new header when we want to send
another packet.

To this end, rename the original header struct to rxrpc_wire_header (with
BE fields) and institute a variant called rxrpc_host_header that has host
order fields.  Change the struct in the sk_buff private data into an
rxrpc_host_header and translate the values when filling it in.

This further allows us to keep values kept in various structures in host
byte order rather than network byte order and allows removal of some fields
that are byteswapped duplicates.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-03-04 15:53:46 +00:00

926 lines
22 KiB
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"
/*
* Time till a connection expires after last use (in seconds).
*/
unsigned rxrpc_connection_expiry = 10 * 60;
static void rxrpc_connection_reaper(struct work_struct *work);
LIST_HEAD(rxrpc_connections);
DEFINE_RWLOCK(rxrpc_connection_lock);
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, u16 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,
u16 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, 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_wire_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 cid;
_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;
cid = 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 (cid < xconn->cid)
p = &(*p)->rb_left;
else if (cid > xconn->cid)
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->cid = cid;
write_unlock_bh(&conn->trans->conn_lock);
_leave(" [CID %x]", 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 (;;) {
cid += RXRPC_CID_INC;
if (cid < RXRPC_CID_INC) {
cid = RXRPC_CID_INC;
conn->trans->conn_idcounter = cid;
goto attempt_insertion;
}
parent = rb_next(parent);
if (!parent)
goto attempt_insertion;
xconn = rb_entry(parent, struct rxrpc_connection, node);
if (epoch < xconn->epoch ||
cid < xconn->cid)
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,
u16 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;
} else {
spin_lock(&trans->client_lock);
}
/* 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 | chan;
call->call_id = ++conn->call_counter;
_net("CONNECT client on conn %d chan %d as call %x",
conn->debug_id, chan, 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 (!gfpflags_allow_blocking(gfp)) {
_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 | chan;
call->call_id = ++conn->call_counter;
_net("CONNECT client on conn %d chan %d as call %x",
conn->debug_id, chan, 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_host_header *hdr,
gfp_t gfp)
{
struct rxrpc_connection *conn, *candidate = NULL;
struct rb_node *p, **pp;
const char *new = "old";
__be32 epoch;
u32 cid;
_enter("");
ASSERT(hdr->flags & RXRPC_CLIENT_INITIATED);
epoch = hdr->epoch;
cid = 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->cid);
if (epoch < conn->epoch)
p = p->rb_left;
else if (epoch > conn->epoch)
p = p->rb_right;
else if (cid < conn->cid)
p = p->rb_left;
else if (cid > conn->cid)
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 & RXRPC_CIDMASK;
candidate->service_id = hdr->serviceId;
candidate->security_ix = hdr->securityIndex;
candidate->in_clientflag = RXRPC_CLIENT_INITIATED;
candidate->out_clientflag = 0;
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 (cid < conn->cid)
pp = &(*pp)->rb_left;
else if (cid > conn->cid)
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->cid);
_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_host_header *hdr)
{
struct rxrpc_connection *conn;
struct rb_node *p;
u32 epoch, cid;
_enter(",{%x,%x}", hdr->cid, hdr->flags);
read_lock_bh(&trans->conn_lock);
cid = 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->cid);
if (epoch < conn->epoch)
p = p->rb_left;
else if (epoch > conn->epoch)
p = p->rb_right;
else if (cid < conn->cid)
p = p->rb_left;
else if (cid > conn->cid)
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 = ktime_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 = ktime_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_expiry;
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_expiry = 0;
cancel_delayed_work(&rxrpc_connection_reap);
rxrpc_queue_delayed_work(&rxrpc_connection_reap, 0);
_leave("");
}