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msm-4.14/net/rxrpc/call_object.c
David Howells 45025bceef rxrpc: Improve management and caching of client connection objects 
Improve the management and caching of client rxrpc connection objects.
From this point, client connections will be managed separately from service
connections because AF_RXRPC controls the creation and re-use of client
connections but doesn't have that luxury with service connections.

Further, there will be limits on the numbers of client connections that may
be live on a machine.  No direct restriction will be placed on the number
of client calls, excepting that each client connection can support a
maximum of four concurrent calls.

Note that, for a number of reasons, we don't want to simply discard a
client connection as soon as the last call is apparently finished:

 (1) Security is negotiated per-connection and the context is then shared
     between all calls on that connection.  The context can be negotiated
     again if the connection lapses, but that involves holding up calls
     whilst at least two packets are exchanged and various crypto bits are
     performed - so we'd ideally like to cache it for a little while at
     least.

 (2) If a packet goes astray, we will need to retransmit a final ACK or
     ABORT packet.  To make this work, we need to keep around the
     connection details for a little while.

 (3) The locally held structures represent some amount of setup time, to be
     weighed against their occupation of memory when idle.


To this end, the client connection cache is managed by a state machine on
each connection.  There are five states:

 (1) INACTIVE - The connection is not held in any list and may not have
     been exposed to the world.  If it has been previously exposed, it was
     discarded from the idle list after expiring.

 (2) WAITING - The connection is waiting for the number of client conns to
     drop below the maximum capacity.  Calls may be in progress upon it
     from when it was active and got culled.

     The connection is on the rxrpc_waiting_client_conns list which is kept
     in to-be-granted order.  Culled conns with waiters go to the back of
     the queue just like new conns.

 (3) ACTIVE - The connection has at least one call in progress upon it, it
     may freely grant available channels to new calls and calls may be
     waiting on it for channels to become available.

     The connection is on the rxrpc_active_client_conns list which is kept
     in activation order for culling purposes.

 (4) CULLED - The connection got summarily culled to try and free up
     capacity.  Calls currently in progress on the connection are allowed
     to continue, but new calls will have to wait.  There can be no waiters
     in this state - the conn would have to go to the WAITING state
     instead.

 (5) IDLE - The connection has no calls in progress upon it and must have
     been exposed to the world (ie. the EXPOSED flag must be set).  When it
     expires, the EXPOSED flag is cleared and the connection transitions to
     the INACTIVE state.

     The connection is on the rxrpc_idle_client_conns list which is kept in
     order of how soon they'll expire.

A connection in the ACTIVE or CULLED state must have at least one active
call upon it; if in the WAITING state it may have active calls upon it;
other states may not have active calls.

As long as a connection remains active and doesn't get culled, it may
continue to process calls - even if there are connections on the wait
queue.  This simplifies things a bit and reduces the amount of checking we
need do.


There are a couple flags of relevance to the cache:

 (1) EXPOSED - The connection ID got exposed to the world.  If this flag is
     set, an extra ref is added to the connection preventing it from being
     reaped when it has no calls outstanding.  This flag is cleared and the
     ref dropped when a conn is discarded from the idle list.

 (2) DONT_REUSE - The connection should be discarded as soon as possible and
     should not be reused.


This commit also provides a number of new settings:

 (*) /proc/net/rxrpc/max_client_conns

     The maximum number of live client connections.  Above this number, new
     connections get added to the wait list and must wait for an active
     conn to be culled.  Culled connections can be reused, but they will go
     to the back of the wait list and have to wait.

 (*) /proc/net/rxrpc/reap_client_conns

     If the number of desired connections exceeds the maximum above, the
     active connection list will be culled until there are only this many
     left in it.

 (*) /proc/net/rxrpc/idle_conn_expiry

     The normal expiry time for a client connection, provided there are
     fewer than reap_client_conns of them around.

 (*) /proc/net/rxrpc/idle_conn_fast_expiry

     The expedited expiry time, used when there are more than
     reap_client_conns of them around.


Note that I combined the Tx wait queue with the channel grant wait queue to
save space as only one of these should be in use at once.

Note also that, for the moment, the service connection cache still uses the
old connection management code.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-24 15:17:14 +01:00

800 lines
21 KiB
C
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/* RxRPC individual remote procedure call handling
*
* 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/circ_buf.h>
#include <linux/spinlock_types.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include "ar-internal.h"
/*
* Maximum lifetime of a call (in jiffies).
*/
unsigned int rxrpc_max_call_lifetime = 60 * HZ;
/*
* Time till dead call expires after last use (in jiffies).
*/
unsigned int rxrpc_dead_call_expiry = 2 * HZ;
const char *const rxrpc_call_states[NR__RXRPC_CALL_STATES] = {
[RXRPC_CALL_UNINITIALISED] = "Uninit",
[RXRPC_CALL_CLIENT_AWAIT_CONN] = "ClWtConn",
[RXRPC_CALL_CLIENT_SEND_REQUEST] = "ClSndReq",
[RXRPC_CALL_CLIENT_AWAIT_REPLY] = "ClAwtRpl",
[RXRPC_CALL_CLIENT_RECV_REPLY] = "ClRcvRpl",
[RXRPC_CALL_CLIENT_FINAL_ACK] = "ClFnlACK",
[RXRPC_CALL_SERVER_SECURING] = "SvSecure",
[RXRPC_CALL_SERVER_ACCEPTING] = "SvAccept",
[RXRPC_CALL_SERVER_RECV_REQUEST] = "SvRcvReq",
[RXRPC_CALL_SERVER_ACK_REQUEST] = "SvAckReq",
[RXRPC_CALL_SERVER_SEND_REPLY] = "SvSndRpl",
[RXRPC_CALL_SERVER_AWAIT_ACK] = "SvAwtACK",
[RXRPC_CALL_COMPLETE] = "Complete",
[RXRPC_CALL_SERVER_BUSY] = "SvBusy ",
[RXRPC_CALL_REMOTELY_ABORTED] = "RmtAbort",
[RXRPC_CALL_LOCALLY_ABORTED] = "LocAbort",
[RXRPC_CALL_NETWORK_ERROR] = "NetError",
[RXRPC_CALL_DEAD] = "Dead ",
};
struct kmem_cache *rxrpc_call_jar;
LIST_HEAD(rxrpc_calls);
DEFINE_RWLOCK(rxrpc_call_lock);
static void rxrpc_destroy_call(struct work_struct *work);
static void rxrpc_call_life_expired(unsigned long _call);
static void rxrpc_dead_call_expired(unsigned long _call);
static void rxrpc_ack_time_expired(unsigned long _call);
static void rxrpc_resend_time_expired(unsigned long _call);
/*
* find an extant server call
* - called in process context with IRQs enabled
*/
struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *rx,
unsigned long user_call_ID)
{
struct rxrpc_call *call;
struct rb_node *p;
_enter("%p,%lx", rx, user_call_ID);
read_lock(&rx->call_lock);
p = rx->calls.rb_node;
while (p) {
call = rb_entry(p, struct rxrpc_call, sock_node);
if (user_call_ID < call->user_call_ID)
p = p->rb_left;
else if (user_call_ID > call->user_call_ID)
p = p->rb_right;
else
goto found_extant_call;
}
read_unlock(&rx->call_lock);
_leave(" = NULL");
return NULL;
found_extant_call:
rxrpc_get_call(call);
read_unlock(&rx->call_lock);
_leave(" = %p [%d]", call, atomic_read(&call->usage));
return call;
}
/*
* allocate a new call
*/
static struct rxrpc_call *rxrpc_alloc_call(gfp_t gfp)
{
struct rxrpc_call *call;
call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
if (!call)
return NULL;
call->acks_winsz = 16;
call->acks_window = kmalloc(call->acks_winsz * sizeof(unsigned long),
gfp);
if (!call->acks_window) {
kmem_cache_free(rxrpc_call_jar, call);
return NULL;
}
setup_timer(&call->lifetimer, &rxrpc_call_life_expired,
(unsigned long) call);
setup_timer(&call->deadspan, &rxrpc_dead_call_expired,
(unsigned long) call);
setup_timer(&call->ack_timer, &rxrpc_ack_time_expired,
(unsigned long) call);
setup_timer(&call->resend_timer, &rxrpc_resend_time_expired,
(unsigned long) call);
INIT_WORK(&call->destroyer, &rxrpc_destroy_call);
INIT_WORK(&call->processor, &rxrpc_process_call);
INIT_LIST_HEAD(&call->link);
INIT_LIST_HEAD(&call->chan_wait_link);
INIT_LIST_HEAD(&call->accept_link);
skb_queue_head_init(&call->rx_queue);
skb_queue_head_init(&call->rx_oos_queue);
init_waitqueue_head(&call->waitq);
spin_lock_init(&call->lock);
rwlock_init(&call->state_lock);
atomic_set(&call->usage, 1);
call->debug_id = atomic_inc_return(&rxrpc_debug_id);
memset(&call->sock_node, 0xed, sizeof(call->sock_node));
call->rx_data_expect = 1;
call->rx_data_eaten = 0;
call->rx_first_oos = 0;
call->ackr_win_top = call->rx_data_eaten + 1 + rxrpc_rx_window_size;
call->creation_jif = jiffies;
return call;
}
/*
* Allocate a new client call.
*/
static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
struct sockaddr_rxrpc *srx,
gfp_t gfp)
{
struct rxrpc_call *call;
_enter("");
ASSERT(rx->local != NULL);
call = rxrpc_alloc_call(gfp);
if (!call)
return ERR_PTR(-ENOMEM);
call->state = RXRPC_CALL_CLIENT_AWAIT_CONN;
sock_hold(&rx->sk);
call->socket = rx;
call->rx_data_post = 1;
call->service_id = srx->srx_service;
_leave(" = %p", call);
return call;
}
/*
* Begin client call.
*/
static int rxrpc_begin_client_call(struct rxrpc_call *call,
struct rxrpc_conn_parameters *cp,
struct sockaddr_rxrpc *srx,
gfp_t gfp)
{
int ret;
/* Set up or get a connection record and set the protocol parameters,
* including channel number and call ID.
*/
ret = rxrpc_connect_call(call, cp, srx, gfp);
if (ret < 0)
return ret;
call->state = RXRPC_CALL_CLIENT_SEND_REQUEST;
spin_lock(&call->conn->params.peer->lock);
hlist_add_head(&call->error_link, &call->conn->params.peer->error_targets);
spin_unlock(&call->conn->params.peer->lock);
call->lifetimer.expires = jiffies + rxrpc_max_call_lifetime;
add_timer(&call->lifetimer);
return 0;
}
/*
* set up a call for the given data
* - called in process context with IRQs enabled
*/
struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
struct rxrpc_conn_parameters *cp,
struct sockaddr_rxrpc *srx,
unsigned long user_call_ID,
gfp_t gfp)
{
struct rxrpc_call *call, *xcall;
struct rb_node *parent, **pp;
int ret;
_enter("%p,%lx", rx, user_call_ID);
call = rxrpc_alloc_client_call(rx, srx, gfp);
if (IS_ERR(call)) {
_leave(" = %ld", PTR_ERR(call));
return call;
}
/* Publish the call, even though it is incompletely set up as yet */
call->user_call_ID = user_call_ID;
__set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
write_lock(&rx->call_lock);
pp = &rx->calls.rb_node;
parent = NULL;
while (*pp) {
parent = *pp;
xcall = rb_entry(parent, struct rxrpc_call, sock_node);
if (user_call_ID < xcall->user_call_ID)
pp = &(*pp)->rb_left;
else if (user_call_ID > xcall->user_call_ID)
pp = &(*pp)->rb_right;
else
goto found_user_ID_now_present;
}
rxrpc_get_call(call);
rb_link_node(&call->sock_node, parent, pp);
rb_insert_color(&call->sock_node, &rx->calls);
write_unlock(&rx->call_lock);
write_lock_bh(&rxrpc_call_lock);
list_add_tail(&call->link, &rxrpc_calls);
write_unlock_bh(&rxrpc_call_lock);
ret = rxrpc_begin_client_call(call, cp, srx, gfp);
if (ret < 0)
goto error;
_net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
_leave(" = %p [new]", call);
return call;
error:
write_lock(&rx->call_lock);
rb_erase(&call->sock_node, &rx->calls);
write_unlock(&rx->call_lock);
rxrpc_put_call(call);
write_lock_bh(&rxrpc_call_lock);
list_del_init(&call->link);
write_unlock_bh(&rxrpc_call_lock);
set_bit(RXRPC_CALL_RELEASED, &call->flags);
call->state = RXRPC_CALL_DEAD;
rxrpc_put_call(call);
_leave(" = %d", ret);
return ERR_PTR(ret);
/* We unexpectedly found the user ID in the list after taking
* the call_lock. This shouldn't happen unless the user races
* with itself and tries to add the same user ID twice at the
* same time in different threads.
*/
found_user_ID_now_present:
write_unlock(&rx->call_lock);
set_bit(RXRPC_CALL_RELEASED, &call->flags);
call->state = RXRPC_CALL_DEAD;
rxrpc_put_call(call);
_leave(" = -EEXIST [%p]", call);
return ERR_PTR(-EEXIST);
}
/*
* set up an incoming call
* - called in process context with IRQs enabled
*/
struct rxrpc_call *rxrpc_incoming_call(struct rxrpc_sock *rx,
struct rxrpc_connection *conn,
struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
struct rxrpc_call *call, *candidate;
u32 call_id, chan;
_enter(",%d", conn->debug_id);
ASSERT(rx != NULL);
candidate = rxrpc_alloc_call(GFP_NOIO);
if (!candidate)
return ERR_PTR(-EBUSY);
chan = sp->hdr.cid & RXRPC_CHANNELMASK;
candidate->socket = rx;
candidate->conn = conn;
candidate->peer = conn->params.peer;
candidate->cid = sp->hdr.cid;
candidate->call_id = sp->hdr.callNumber;
candidate->rx_data_post = 0;
candidate->state = RXRPC_CALL_SERVER_ACCEPTING;
candidate->flags |= (1 << RXRPC_CALL_IS_SERVICE);
if (conn->security_ix > 0)
candidate->state = RXRPC_CALL_SERVER_SECURING;
spin_lock(&conn->channel_lock);
/* set the channel for this call */
call = rcu_dereference_protected(conn->channels[chan].call,
lockdep_is_held(&conn->channel_lock));
_debug("channel[%u] is %p", candidate->cid & RXRPC_CHANNELMASK, call);
if (call && call->call_id == sp->hdr.callNumber) {
/* already set; must've been a duplicate packet */
_debug("extant call [%d]", call->state);
ASSERTCMP(call->conn, ==, conn);
read_lock(&call->state_lock);
switch (call->state) {
case RXRPC_CALL_LOCALLY_ABORTED:
if (!test_and_set_bit(RXRPC_CALL_EV_ABORT, &call->events))
rxrpc_queue_call(call);
case RXRPC_CALL_REMOTELY_ABORTED:
read_unlock(&call->state_lock);
goto aborted_call;
default:
rxrpc_get_call(call);
read_unlock(&call->state_lock);
goto extant_call;
}
}
if (call) {
/* it seems the channel is still in use from the previous call
* - ditch the old binding if its call is now complete */
_debug("CALL: %u { %s }",
call->debug_id, rxrpc_call_states[call->state]);
if (call->state >= RXRPC_CALL_COMPLETE) {
__rxrpc_disconnect_call(conn, call);
} else {
spin_unlock(&conn->channel_lock);
kmem_cache_free(rxrpc_call_jar, candidate);
_leave(" = -EBUSY");
return ERR_PTR(-EBUSY);
}
}
/* check the call number isn't duplicate */
_debug("check dup");
call_id = sp->hdr.callNumber;
/* We just ignore calls prior to the current call ID. Terminated calls
* are handled via the connection.
*/
if (call_id <= conn->channels[chan].call_counter)
goto old_call; /* TODO: Just drop packet */
/* make the call available */
_debug("new call");
call = candidate;
candidate = NULL;
conn->channels[chan].call_counter = call_id;
rcu_assign_pointer(conn->channels[chan].call, call);
sock_hold(&rx->sk);
rxrpc_get_connection(conn);
rxrpc_get_peer(call->peer);
spin_unlock(&conn->channel_lock);
spin_lock(&conn->params.peer->lock);
hlist_add_head(&call->error_link, &conn->params.peer->error_targets);
spin_unlock(&conn->params.peer->lock);
write_lock_bh(&rxrpc_call_lock);
list_add_tail(&call->link, &rxrpc_calls);
write_unlock_bh(&rxrpc_call_lock);
call->service_id = conn->params.service_id;
_net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
call->lifetimer.expires = jiffies + rxrpc_max_call_lifetime;
add_timer(&call->lifetimer);
_leave(" = %p {%d} [new]", call, call->debug_id);
return call;
extant_call:
spin_unlock(&conn->channel_lock);
kmem_cache_free(rxrpc_call_jar, candidate);
_leave(" = %p {%d} [extant]", call, call ? call->debug_id : -1);
return call;
aborted_call:
spin_unlock(&conn->channel_lock);
kmem_cache_free(rxrpc_call_jar, candidate);
_leave(" = -ECONNABORTED");
return ERR_PTR(-ECONNABORTED);
old_call:
spin_unlock(&conn->channel_lock);
kmem_cache_free(rxrpc_call_jar, candidate);
_leave(" = -ECONNRESET [old]");
return ERR_PTR(-ECONNRESET);
}
/*
* detach a call from a socket and set up for release
*/
void rxrpc_release_call(struct rxrpc_call *call)
{
struct rxrpc_connection *conn = call->conn;
struct rxrpc_sock *rx = call->socket;
_enter("{%d,%d,%d,%d}",
call->debug_id, atomic_read(&call->usage),
atomic_read(&call->ackr_not_idle),
call->rx_first_oos);
spin_lock_bh(&call->lock);
if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
BUG();
spin_unlock_bh(&call->lock);
/* dissociate from the socket
* - the socket's ref on the call is passed to the death timer
*/
_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
spin_lock(&conn->params.peer->lock);
hlist_del_init(&call->error_link);
spin_unlock(&conn->params.peer->lock);
write_lock_bh(&rx->call_lock);
if (!list_empty(&call->accept_link)) {
_debug("unlinking once-pending call %p { e=%lx f=%lx }",
call, call->events, call->flags);
ASSERT(!test_bit(RXRPC_CALL_HAS_USERID, &call->flags));
list_del_init(&call->accept_link);
sk_acceptq_removed(&rx->sk);
} else if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
rb_erase(&call->sock_node, &rx->calls);
memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
clear_bit(RXRPC_CALL_HAS_USERID, &call->flags);
}
write_unlock_bh(&rx->call_lock);
/* free up the channel for reuse */
write_lock_bh(&call->state_lock);
if (call->state < RXRPC_CALL_COMPLETE &&
call->state != RXRPC_CALL_CLIENT_FINAL_ACK) {
_debug("+++ ABORTING STATE %d +++\n", call->state);
call->state = RXRPC_CALL_LOCALLY_ABORTED;
call->local_abort = RX_CALL_DEAD;
}
write_unlock_bh(&call->state_lock);
rxrpc_disconnect_call(call);
/* clean up the Rx queue */
if (!skb_queue_empty(&call->rx_queue) ||
!skb_queue_empty(&call->rx_oos_queue)) {
struct rxrpc_skb_priv *sp;
struct sk_buff *skb;
_debug("purge Rx queues");
spin_lock_bh(&call->lock);
while ((skb = skb_dequeue(&call->rx_queue)) ||
(skb = skb_dequeue(&call->rx_oos_queue))) {
spin_unlock_bh(&call->lock);
sp = rxrpc_skb(skb);
_debug("- zap %s %%%u #%u",
rxrpc_pkts[sp->hdr.type],
sp->hdr.serial, sp->hdr.seq);
rxrpc_free_skb(skb);
spin_lock_bh(&call->lock);
}
spin_unlock_bh(&call->lock);
ASSERTCMP(call->state, !=, RXRPC_CALL_COMPLETE);
}
del_timer_sync(&call->resend_timer);
del_timer_sync(&call->ack_timer);
del_timer_sync(&call->lifetimer);
call->deadspan.expires = jiffies + rxrpc_dead_call_expiry;
add_timer(&call->deadspan);
_leave("");
}
/*
* handle a dead call being ready for reaping
*/
static void rxrpc_dead_call_expired(unsigned long _call)
{
struct rxrpc_call *call = (struct rxrpc_call *) _call;
_enter("{%d}", call->debug_id);
write_lock_bh(&call->state_lock);
call->state = RXRPC_CALL_DEAD;
write_unlock_bh(&call->state_lock);
rxrpc_put_call(call);
}
/*
* mark a call as to be released, aborting it if it's still in progress
* - called with softirqs disabled
*/
static void rxrpc_mark_call_released(struct rxrpc_call *call)
{
bool sched;
write_lock(&call->state_lock);
if (call->state < RXRPC_CALL_DEAD) {
sched = false;
if (call->state < RXRPC_CALL_COMPLETE) {
_debug("abort call %p", call);
call->state = RXRPC_CALL_LOCALLY_ABORTED;
call->local_abort = RX_CALL_DEAD;
if (!test_and_set_bit(RXRPC_CALL_EV_ABORT, &call->events))
sched = true;
}
if (!test_and_set_bit(RXRPC_CALL_EV_RELEASE, &call->events))
sched = true;
if (sched)
rxrpc_queue_call(call);
}
write_unlock(&call->state_lock);
}
/*
* release all the calls associated with a socket
*/
void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
{
struct rxrpc_call *call;
struct rb_node *p;
_enter("%p", rx);
read_lock_bh(&rx->call_lock);
/* kill the not-yet-accepted incoming calls */
list_for_each_entry(call, &rx->secureq, accept_link) {
rxrpc_mark_call_released(call);
}
list_for_each_entry(call, &rx->acceptq, accept_link) {
rxrpc_mark_call_released(call);
}
/* mark all the calls as no longer wanting incoming packets */
for (p = rb_first(&rx->calls); p; p = rb_next(p)) {
call = rb_entry(p, struct rxrpc_call, sock_node);
rxrpc_mark_call_released(call);
}
read_unlock_bh(&rx->call_lock);
_leave("");
}
/*
* release a call
*/
void __rxrpc_put_call(struct rxrpc_call *call)
{
ASSERT(call != NULL);
_enter("%p{u=%d}", call, atomic_read(&call->usage));
ASSERTCMP(atomic_read(&call->usage), >, 0);
if (atomic_dec_and_test(&call->usage)) {
_debug("call %d dead", call->debug_id);
WARN_ON(atomic_read(&call->skb_count) != 0);
ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
rxrpc_queue_work(&call->destroyer);
}
_leave("");
}
/*
* Final call destruction under RCU.
*/
static void rxrpc_rcu_destroy_call(struct rcu_head *rcu)
{
struct rxrpc_call *call = container_of(rcu, struct rxrpc_call, rcu);
rxrpc_purge_queue(&call->rx_queue);
rxrpc_put_peer(call->peer);
kmem_cache_free(rxrpc_call_jar, call);
}
/*
* clean up a call
*/
static void rxrpc_cleanup_call(struct rxrpc_call *call)
{
_net("DESTROY CALL %d", call->debug_id);
ASSERT(call->socket);
memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
del_timer_sync(&call->lifetimer);
del_timer_sync(&call->deadspan);
del_timer_sync(&call->ack_timer);
del_timer_sync(&call->resend_timer);
ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
ASSERTCMP(call->events, ==, 0);
if (work_pending(&call->processor)) {
_debug("defer destroy");
rxrpc_queue_work(&call->destroyer);
return;
}
ASSERTCMP(call->conn, ==, NULL);
if (call->acks_window) {
_debug("kill Tx window %d",
CIRC_CNT(call->acks_head, call->acks_tail,
call->acks_winsz));
smp_mb();
while (CIRC_CNT(call->acks_head, call->acks_tail,
call->acks_winsz) > 0) {
struct rxrpc_skb_priv *sp;
unsigned long _skb;
_skb = call->acks_window[call->acks_tail] & ~1;
sp = rxrpc_skb((struct sk_buff *)_skb);
_debug("+++ clear Tx %u", sp->hdr.seq);
rxrpc_free_skb((struct sk_buff *)_skb);
call->acks_tail =
(call->acks_tail + 1) & (call->acks_winsz - 1);
}
kfree(call->acks_window);
}
rxrpc_free_skb(call->tx_pending);
rxrpc_purge_queue(&call->rx_queue);
ASSERT(skb_queue_empty(&call->rx_oos_queue));
sock_put(&call->socket->sk);
call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
}
/*
* destroy a call
*/
static void rxrpc_destroy_call(struct work_struct *work)
{
struct rxrpc_call *call =
container_of(work, struct rxrpc_call, destroyer);
_enter("%p{%d,%x,%p}",
call, atomic_read(&call->usage), call->cid, call->conn);
ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
write_lock_bh(&rxrpc_call_lock);
list_del_init(&call->link);
write_unlock_bh(&rxrpc_call_lock);
rxrpc_cleanup_call(call);
_leave("");
}
/*
* preemptively destroy all the call records from a transport endpoint rather
* than waiting for them to time out
*/
void __exit rxrpc_destroy_all_calls(void)
{
struct rxrpc_call *call;
_enter("");
write_lock_bh(&rxrpc_call_lock);
while (!list_empty(&rxrpc_calls)) {
call = list_entry(rxrpc_calls.next, struct rxrpc_call, link);
_debug("Zapping call %p", call);
list_del_init(&call->link);
switch (atomic_read(&call->usage)) {
case 0:
ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
break;
case 1:
if (del_timer_sync(&call->deadspan) != 0 &&
call->state != RXRPC_CALL_DEAD)
rxrpc_dead_call_expired((unsigned long) call);
if (call->state != RXRPC_CALL_DEAD)
break;
default:
pr_err("Call %p still in use (%d,%d,%s,%lx,%lx)!\n",
call, atomic_read(&call->usage),
atomic_read(&call->ackr_not_idle),
rxrpc_call_states[call->state],
call->flags, call->events);
if (!skb_queue_empty(&call->rx_queue))
pr_err("Rx queue occupied\n");
if (!skb_queue_empty(&call->rx_oos_queue))
pr_err("OOS queue occupied\n");
break;
}
write_unlock_bh(&rxrpc_call_lock);
cond_resched();
write_lock_bh(&rxrpc_call_lock);
}
write_unlock_bh(&rxrpc_call_lock);
_leave("");
}
/*
* handle call lifetime being exceeded
*/
static void rxrpc_call_life_expired(unsigned long _call)
{
struct rxrpc_call *call = (struct rxrpc_call *) _call;
if (call->state >= RXRPC_CALL_COMPLETE)
return;
_enter("{%d}", call->debug_id);
read_lock_bh(&call->state_lock);
if (call->state < RXRPC_CALL_COMPLETE) {
set_bit(RXRPC_CALL_EV_LIFE_TIMER, &call->events);
rxrpc_queue_call(call);
}
read_unlock_bh(&call->state_lock);
}
/*
* handle resend timer expiry
* - may not take call->state_lock as this can deadlock against del_timer_sync()
*/
static void rxrpc_resend_time_expired(unsigned long _call)
{
struct rxrpc_call *call = (struct rxrpc_call *) _call;
_enter("{%d}", call->debug_id);
if (call->state >= RXRPC_CALL_COMPLETE)
return;
clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
if (!test_and_set_bit(RXRPC_CALL_EV_RESEND_TIMER, &call->events))
rxrpc_queue_call(call);
}
/*
* handle ACK timer expiry
*/
static void rxrpc_ack_time_expired(unsigned long _call)
{
struct rxrpc_call *call = (struct rxrpc_call *) _call;
_enter("{%d}", call->debug_id);
if (call->state >= RXRPC_CALL_COMPLETE)
return;
read_lock_bh(&call->state_lock);
if (call->state < RXRPC_CALL_COMPLETE &&
!test_and_set_bit(RXRPC_CALL_EV_ACK, &call->events))
rxrpc_queue_call(call);
read_unlock_bh(&call->state_lock);
}
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