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root/net/rxrpc/ar-call.c

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DEFINITIONS

This source file includes following definitions.
  1. rxrpc_alloc_call
  2. rxrpc_alloc_client_call
  3. rxrpc_get_client_call
  4. rxrpc_incoming_call
  5. rxrpc_find_server_call
  6. rxrpc_release_call
  7. rxrpc_dead_call_expired
  8. rxrpc_mark_call_released
  9. rxrpc_release_calls_on_socket
  10. __rxrpc_put_call
  11. rxrpc_cleanup_call
  12. rxrpc_destroy_call
  13. rxrpc_destroy_all_calls
  14. rxrpc_call_life_expired
  15. rxrpc_resend_time_expired
  16. rxrpc_ack_time_expired

/* 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.
 */

#include <linux/module.h>
#include <linux/circ_buf.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include "ar-internal.h"

const char *const rxrpc_call_states[] = {
        [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 unsigned rxrpc_call_max_lifetime = 60;
static unsigned rxrpc_dead_call_timeout = 2;

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);

/*
 * 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->accept_link);
        skb_queue_head_init(&call->rx_queue);
        skb_queue_head_init(&call->rx_oos_queue);
        init_waitqueue_head(&call->tx_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);
        call->state = RXRPC_CALL_CLIENT_SEND_REQUEST;

        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_MAXACKS;
        call->creation_jif = jiffies;
        return call;
}

/*
 * allocate a new client call and attempt to to get a connection slot for it
 */
static struct rxrpc_call *rxrpc_alloc_client_call(
        struct rxrpc_sock *rx,
        struct rxrpc_transport *trans,
        struct rxrpc_conn_bundle *bundle,
        gfp_t gfp)
{
        struct rxrpc_call *call;
        int ret;

        _enter("");

        ASSERT(rx != NULL);
        ASSERT(trans != NULL);
        ASSERT(bundle != NULL);

        call = rxrpc_alloc_call(gfp);
        if (!call)
                return ERR_PTR(-ENOMEM);

        sock_hold(&rx->sk);
        call->socket = rx;
        call->rx_data_post = 1;

        ret = rxrpc_connect_call(rx, trans, bundle, call, gfp);
        if (ret < 0) {
                kmem_cache_free(rxrpc_call_jar, call);
                return ERR_PTR(ret);
        }

        spin_lock(&call->conn->trans->peer->lock);
        list_add(&call->error_link, &call->conn->trans->peer->error_targets);
        spin_unlock(&call->conn->trans->peer->lock);

        call->lifetimer.expires = jiffies + rxrpc_call_max_lifetime * HZ;
        add_timer(&call->lifetimer);

        _leave(" = %p", call);
        return call;
}

/*
 * set up a call for the given data
 * - called in process context with IRQs enabled
 */
struct rxrpc_call *rxrpc_get_client_call(struct rxrpc_sock *rx,
                                         struct rxrpc_transport *trans,
                                         struct rxrpc_conn_bundle *bundle,
                                         unsigned long user_call_ID,
                                         int create,
                                         gfp_t gfp)
{
        struct rxrpc_call *call, *candidate;
        struct rb_node *p, *parent, **pp;

        _enter("%p,%d,%d,%lx,%d",
               rx, trans ? trans->debug_id : -1, bundle ? bundle->debug_id : -1,
               user_call_ID, create);

        /* search the extant calls first for one that matches the specified
         * user 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);

        if (!create || !trans)
                return ERR_PTR(-EBADSLT);

        /* not yet present - create a candidate for a new record and then
         * redo the search */
        candidate = rxrpc_alloc_client_call(rx, trans, bundle, gfp);
        if (IS_ERR(candidate)) {
                _leave(" = %ld", PTR_ERR(candidate));
                return candidate;
        }

        candidate->user_call_ID = user_call_ID;
        __set_bit(RXRPC_CALL_HAS_USERID, &candidate->flags);

        write_lock(&rx->call_lock);

        pp = &rx->calls.rb_node;
        parent = NULL;
        while (*pp) {
                parent = *pp;
                call = rb_entry(parent, struct rxrpc_call, sock_node);

                if (user_call_ID < call->user_call_ID)
                        pp = &(*pp)->rb_left;
                else if (user_call_ID > call->user_call_ID)
                        pp = &(*pp)->rb_right;
                else
                        goto found_extant_second;
        }

        /* second search also failed; add the new call */
        call = candidate;
        candidate = NULL;
        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);

        _net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);

        _leave(" = %p [new]", call);
        return call;

        /* we found the call in the list immediately */
found_extant_call:
        rxrpc_get_call(call);
        read_unlock(&rx->call_lock);
        _leave(" = %p [extant %d]", call, atomic_read(&call->usage));
        return call;

        /* we found the call on the second time through the list */
found_extant_second:
        rxrpc_get_call(call);
        write_unlock(&rx->call_lock);
        rxrpc_put_call(candidate);
        _leave(" = %p [second %d]", call, atomic_read(&call->usage));
        return call;
}

/*
 * 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 rxrpc_header *hdr,
                                       gfp_t gfp)
{
        struct rxrpc_call *call, *candidate;
        struct rb_node **p, *parent;
        __be32 call_id;

        _enter(",%d,,%x", conn->debug_id, gfp);

        ASSERT(rx != NULL);

        candidate = rxrpc_alloc_call(gfp);
        if (!candidate)
                return ERR_PTR(-EBUSY);

        candidate->socket = rx;
        candidate->conn = conn;
        candidate->cid = hdr->cid;
        candidate->call_id = hdr->callNumber;
        candidate->channel = ntohl(hdr->cid) & RXRPC_CHANNELMASK;
        candidate->rx_data_post = 0;
        candidate->state = RXRPC_CALL_SERVER_ACCEPTING;
        if (conn->security_ix > 0)
                candidate->state = RXRPC_CALL_SERVER_SECURING;

        write_lock_bh(&conn->lock);

        /* set the channel for this call */
        call = conn->channels[candidate->channel];
        _debug("channel[%u] is %p", candidate->channel, call);
        if (call && call->call_id == 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_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) {
                        conn->channels[call->channel] = NULL;
                } else {
                        write_unlock_bh(&conn->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 = hdr->callNumber;
        p = &conn->calls.rb_node;
        parent = NULL;
        while (*p) {
                parent = *p;
                call = rb_entry(parent, struct rxrpc_call, conn_node);

                if (call_id < call->call_id)
                        p = &(*p)->rb_left;
                else if (call_id > call->call_id)
                        p = &(*p)->rb_right;
                else
                        goto old_call;
        }

        /* make the call available */
        _debug("new call");
        call = candidate;
        candidate = NULL;
        rb_link_node(&call->conn_node, parent, p);
        rb_insert_color(&call->conn_node, &conn->calls);
        conn->channels[call->channel] = call;
        sock_hold(&rx->sk);
        atomic_inc(&conn->usage);
        write_unlock_bh(&conn->lock);

        spin_lock(&conn->trans->peer->lock);
        list_add(&call->error_link, &conn->trans->peer->error_targets);
        spin_unlock(&conn->trans->peer->lock);

        write_lock_bh(&rxrpc_call_lock);
        list_add_tail(&call->link, &rxrpc_calls);
        write_unlock_bh(&rxrpc_call_lock);

        _net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);

        call->lifetimer.expires = jiffies + rxrpc_call_max_lifetime * HZ;
        add_timer(&call->lifetimer);
        _leave(" = %p {%d} [new]", call, call->debug_id);
        return call;

extant_call:
        write_unlock_bh(&conn->lock);
        kmem_cache_free(rxrpc_call_jar, candidate);
        _leave(" = %p {%d} [extant]", call, call ? call->debug_id : -1);
        return call;

aborted_call:
        write_unlock_bh(&conn->lock);
        kmem_cache_free(rxrpc_call_jar, candidate);
        _leave(" = -ECONNABORTED");
        return ERR_PTR(-ECONNABORTED);

old_call:
        write_unlock_bh(&conn->lock);
        kmem_cache_free(rxrpc_call_jar, candidate);
        _leave(" = -ECONNRESET [old]");
        return ERR_PTR(-ECONNRESET);
}

/*
 * find an extant server call
 * - called in process context with IRQs enabled
 */
struct rxrpc_call *rxrpc_find_server_call(struct rxrpc_sock *rx,
                                          unsigned long user_call_ID)
{
        struct rxrpc_call *call;
        struct rb_node *p;

        _enter("%p,%lx", rx, user_call_ID);

        /* search the extant calls for one that matches the specified user
         * 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;

        /* we found the call in the list immediately */
found_extant_call:
        rxrpc_get_call(call);
        read_unlock(&rx->call_lock);
        _leave(" = %p [%d]", call, atomic_read(&call->usage));
        return call;
}

/*
 * 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);

        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 */
        spin_lock(&conn->trans->client_lock);
        write_lock_bh(&conn->lock);
        write_lock(&call->state_lock);

        if (conn->channels[call->channel] == call)
                conn->channels[call->channel] = NULL;

        if (conn->out_clientflag && conn->bundle) {
                conn->avail_calls++;
                switch (conn->avail_calls) {
                case 1:
                        list_move_tail(&conn->bundle_link,
                                       &conn->bundle->avail_conns);
                case 2 ... RXRPC_MAXCALLS - 1:
                        ASSERT(conn->channels[0] == NULL ||
                               conn->channels[1] == NULL ||
                               conn->channels[2] == NULL ||
                               conn->channels[3] == NULL);
                        break;
                case RXRPC_MAXCALLS:
                        list_move_tail(&conn->bundle_link,
                                       &conn->bundle->unused_conns);
                        ASSERT(conn->channels[0] == NULL &&
                               conn->channels[1] == NULL &&
                               conn->channels[2] == NULL &&
                               conn->channels[3] == NULL);
                        break;
                default:
                        printk(KERN_ERR "RxRPC: conn->avail_calls=%d\n",
                               conn->avail_calls);
                        BUG();
                }
        }

        spin_unlock(&conn->trans->client_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->abort_code = RX_CALL_DEAD;
                set_bit(RXRPC_CALL_ABORT, &call->events);
                rxrpc_queue_call(call);
        }
        write_unlock(&call->state_lock);
        write_unlock_bh(&conn->lock);

        /* 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))) {
                        sp = rxrpc_skb(skb);
                        if (sp->call) {
                                ASSERTCMP(sp->call, ==, call);
                                rxrpc_put_call(call);
                                sp->call = NULL;
                        }
                        skb->destructor = NULL;
                        spin_unlock_bh(&call->lock);

                        _debug("- zap %s %%%u #%u",
                               rxrpc_pkts[sp->hdr.type],
                               ntohl(sp->hdr.serial),
                               ntohl(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_timeout * HZ;
        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->abort_code = RX_CALL_DEAD;
                        if (!test_and_set_bit(RXRPC_CALL_ABORT, &call->events))
                                sched = true;
                }
                if (!test_and_set_bit(RXRPC_CALL_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);

        /* 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);
        }

        /* 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);
        }

        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);
                ASSERTCMP(call->state, ==, RXRPC_CALL_DEAD);
                rxrpc_queue_work(&call->destroyer);
        }
        _leave("");
}

/*
 * 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;
        }

        if (call->conn) {
                spin_lock(&call->conn->trans->peer->lock);
                list_del(&call->error_link);
                spin_unlock(&call->conn->trans->peer->lock);

                write_lock_bh(&call->conn->lock);
                rb_erase(&call->conn_node, &call->conn->calls);
                write_unlock_bh(&call->conn->lock);
                rxrpc_put_connection(call->conn);
        }

        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", ntohl(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);
        kmem_cache_free(rxrpc_call_jar, 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,%d,%p}",
               call, atomic_read(&call->usage), call->channel, 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:
                        printk(KERN_ERR "RXRPC:"
                               " 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))
                                printk(KERN_ERR"RXRPC: Rx queue occupied\n");
                        if (!skb_queue_empty(&call->rx_oos_queue))
                                printk(KERN_ERR"RXRPC: 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_LIFE_TIMER, &call->events);
                rxrpc_queue_call(call);
        }
        read_unlock_bh(&call->state_lock);
}

/*
 * handle resend timer expiry
 */
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;

        read_lock_bh(&call->state_lock);
        clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
        if (call->state < RXRPC_CALL_COMPLETE &&
            !test_and_set_bit(RXRPC_CALL_RESEND_TIMER, &call->events))
                rxrpc_queue_call(call);
        read_unlock_bh(&call->state_lock);
}

/*
 * 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_ACK, &call->events))
                rxrpc_queue_call(call);
        read_unlock_bh(&call->state_lock);
}

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