// SPDX-License-Identifier: GPL-2.0-or-later
/* Client connection-specific management code.
*
* Copyright (C) 2016, 2020 Red Hat, Inc. All Rights Reserved.
* Written by David Howells ([email protected])
*
* Client connections need to be cached for a little while after they've made a
* call so as to handle retransmitted DATA packets in case the server didn't
* receive the final ACK or terminating ABORT we sent it.
*
* There are flags of relevance to the cache:
*
* (2) DONT_REUSE - The connection should be discarded as soon as possible and
* should not be reused. This is set when an exclusive connection is used
* or a call ID counter overflows.
*
* The caching state may only be changed if the cache lock is held.
*
* There are two idle client connection expiry durations. If the total number
* of connections is below the reap threshold, we use the normal duration; if
* it's above, we use the fast duration.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/slab.h>
#include <linux/idr.h>
#include <linux/timer.h>
#include <linux/sched/signal.h>
#include "ar-internal.h"
__read_mostly unsigned int rxrpc_reap_client_connections = 900;
__read_mostly unsigned long rxrpc_conn_idle_client_expiry = 2 * 60 * HZ;
__read_mostly unsigned long rxrpc_conn_idle_client_fast_expiry = 2 * HZ;
static void rxrpc_activate_bundle(struct rxrpc_bundle *bundle)
{
atomic_inc(&bundle->active);
}
/*
* Release a connection ID for a client connection.
*/
static void rxrpc_put_client_connection_id(struct rxrpc_local *local,
struct rxrpc_connection *conn)
{
idr_remove(&local->conn_ids, conn->proto.cid >> RXRPC_CIDSHIFT);
}
/*
* Destroy the client connection ID tree.
*/
static void rxrpc_destroy_client_conn_ids(struct rxrpc_local *local)
{
struct rxrpc_connection *conn;
int id;
if (!idr_is_empty(&local->conn_ids)) {
idr_for_each_entry(&local->conn_ids, conn, id) {
pr_err("AF_RXRPC: Leaked client conn %p {%d}\n",
conn, refcount_read(&conn->ref));
}
BUG();
}
idr_destroy(&local->conn_ids);
}
/*
* Allocate a connection bundle.
*/
static struct rxrpc_bundle *rxrpc_alloc_bundle(struct rxrpc_call *call,
gfp_t gfp)
{
static atomic_t rxrpc_bundle_id;
struct rxrpc_bundle *bundle;
bundle = kzalloc(sizeof(*bundle), gfp);
if (bundle) {
bundle->local = call->local;
bundle->peer = rxrpc_get_peer(call->peer, rxrpc_peer_get_bundle);
bundle->key = key_get(call->key);
bundle->security = call->security;
bundle->exclusive = test_bit(RXRPC_CALL_EXCLUSIVE, &call->flags);
bundle->upgrade = test_bit(RXRPC_CALL_UPGRADE, &call->flags);
bundle->service_id = call->dest_srx.srx_service;
bundle->security_level = call->security_level;
bundle->debug_id = atomic_inc_return(&rxrpc_bundle_id);
refcount_set(&bundle->ref, 1);
atomic_set(&bundle->active, 1);
INIT_LIST_HEAD(&bundle->waiting_calls);
trace_rxrpc_bundle(bundle->debug_id, 1, rxrpc_bundle_new);
write_lock(&bundle->local->rxnet->conn_lock);
list_add_tail(&bundle->proc_link, &bundle->local->rxnet->bundle_proc_list);
write_unlock(&bundle->local->rxnet->conn_lock);
}
return bundle;
}
struct rxrpc_bundle *rxrpc_get_bundle(struct rxrpc_bundle *bundle,
enum rxrpc_bundle_trace why)
{
int r;
__refcount_inc(&bundle->ref, &r);
trace_rxrpc_bundle(bundle->debug_id, r + 1, why);
return bundle;
}
static void rxrpc_free_bundle(struct rxrpc_bundle *bundle)
{
trace_rxrpc_bundle(bundle->debug_id, refcount_read(&bundle->ref),
rxrpc_bundle_free);
write_lock(&bundle->local->rxnet->conn_lock);
list_del(&bundle->proc_link);
write_unlock(&bundle->local->rxnet->conn_lock);
rxrpc_put_peer(bundle->peer, rxrpc_peer_put_bundle);
key_put(bundle->key);
kfree(bundle);
}
void rxrpc_put_bundle(struct rxrpc_bundle *bundle, enum rxrpc_bundle_trace why)
{
unsigned int id;
bool dead;
int r;
if (bundle) {
id = bundle->debug_id;
dead = __refcount_dec_and_test(&bundle->ref, &r);
trace_rxrpc_bundle(id, r - 1, why);
if (dead)
rxrpc_free_bundle(bundle);
}
}
/*
* Get rid of outstanding client connection preallocations when a local
* endpoint is destroyed.
*/
void rxrpc_purge_client_connections(struct rxrpc_local *local)
{
rxrpc_destroy_client_conn_ids(local);
}
/*
* Allocate a client connection.
*/
static struct rxrpc_connection *
rxrpc_alloc_client_connection(struct rxrpc_bundle *bundle)
{
struct rxrpc_connection *conn;
struct rxrpc_local *local = bundle->local;
struct rxrpc_net *rxnet = local->rxnet;
int id;
_enter("");
conn = rxrpc_alloc_connection(rxnet, GFP_ATOMIC | __GFP_NOWARN);
if (!conn)
return ERR_PTR(-ENOMEM);
id = idr_alloc_cyclic(&local->conn_ids, conn, 1, 0x40000000,
GFP_ATOMIC | __GFP_NOWARN);
if (id < 0) {
kfree(conn);
return ERR_PTR(id);
}
refcount_set(&conn->ref, 1);
conn->proto.cid = id << RXRPC_CIDSHIFT;
conn->proto.epoch = local->rxnet->epoch;
conn->out_clientflag = RXRPC_CLIENT_INITIATED;
conn->bundle = rxrpc_get_bundle(bundle, rxrpc_bundle_get_client_conn);
conn->local = rxrpc_get_local(bundle->local, rxrpc_local_get_client_conn);
conn->peer = rxrpc_get_peer(bundle->peer, rxrpc_peer_get_client_conn);
conn->key = key_get(bundle->key);
conn->security = bundle->security;
conn->exclusive = bundle->exclusive;
conn->upgrade = bundle->upgrade;
conn->orig_service_id = bundle->service_id;
conn->security_level = bundle->security_level;
conn->state = RXRPC_CONN_CLIENT_UNSECURED;
conn->service_id = conn->orig_service_id;
if (conn->security == &rxrpc_no_security)
conn->state = RXRPC_CONN_CLIENT;
atomic_inc(&rxnet->nr_conns);
write_lock(&rxnet->conn_lock);
list_add_tail(&conn->proc_link, &rxnet->conn_proc_list);
write_unlock(&rxnet->conn_lock);
rxrpc_see_connection(conn, rxrpc_conn_new_client);
atomic_inc(&rxnet->nr_client_conns);
trace_rxrpc_client(conn, -1, rxrpc_client_alloc);
return conn;
}
/*
* Determine if a connection may be reused.
*/
static bool rxrpc_may_reuse_conn(struct rxrpc_connection *conn)
{
struct rxrpc_net *rxnet;
int id_cursor, id, distance, limit;
if (!conn)
goto dont_reuse;
rxnet = conn->rxnet;
if (test_bit(RXRPC_CONN_DONT_REUSE, &conn->flags))
goto dont_reuse;
if ((conn->state != RXRPC_CONN_CLIENT_UNSECURED &&
conn->state != RXRPC_CONN_CLIENT) ||
conn->proto.epoch != rxnet->epoch)
goto mark_dont_reuse;
/* The IDR tree gets very expensive on memory if the connection IDs are
* widely scattered throughout the number space, so we shall want to
* kill off connections that, say, have an ID more than about four
* times the maximum number of client conns away from the current
* allocation point to try and keep the IDs concentrated.
*/
id_cursor = idr_get_cursor(&conn->local->conn_ids);
id = conn->proto.cid >> RXRPC_CIDSHIFT;
distance = id - id_cursor;
if (distance < 0)
distance = -distance;
limit = max_t(unsigned long, atomic_read(&rxnet->nr_conns) * 4, 1024);
if (distance > limit)
goto mark_dont_reuse;
return true;
mark_dont_reuse:
set_bit(RXRPC_CONN_DONT_REUSE, &conn->flags);
dont_reuse:
return false;
}
/*
* Look up the conn bundle that matches the connection parameters, adding it if
* it doesn't yet exist.
*/
int rxrpc_look_up_bundle(struct rxrpc_call *call, gfp_t gfp)
{
struct rxrpc_bundle *bundle, *candidate;
struct rxrpc_local *local = call->local;
struct rb_node *p, **pp, *parent;
long diff;
bool upgrade = test_bit(RXRPC_CALL_UPGRADE, &call->flags);
_enter("{%px,%x,%u,%u}",
call->peer, key_serial(call->key), call->security_level,
upgrade);
if (test_bit(RXRPC_CALL_EXCLUSIVE, &call->flags)) {
call->bundle = rxrpc_alloc_bundle(call, gfp);
return call->bundle ? 0 : -ENOMEM;
}
/* First, see if the bundle is already there. */
_debug("search 1");
spin_lock(&local->client_bundles_lock);
p = local->client_bundles.rb_node;
while (p) {
bundle = rb_entry(p, struct rxrpc_bundle, local_node);
#define cmp(X, Y) ((long)(X) - (long)(Y))
diff = (cmp(bundle->peer, call->peer) ?:
cmp(bundle->key, call->key) ?:
cmp(bundle->security_level, call->security_level) ?:
cmp(bundle->upgrade, upgrade));
#undef cmp
if (diff < 0)
p = p->rb_left;
else if (diff > 0)
p = p->rb_right;
else
goto found_bundle;
}
spin_unlock(&local->client_bundles_lock);
_debug("not found");
/* It wasn't. We need to add one. */
candidate = rxrpc_alloc_bundle(call, gfp);
if (!candidate)
return -ENOMEM;
_debug("search 2");
spin_lock(&local->client_bundles_lock);
pp = &local->client_bundles.rb_node;
parent = NULL;
while (*pp) {
parent = *pp;
bundle = rb_entry(parent, struct rxrpc_bundle, local_node);
#define cmp(X, Y) ((long)(X) - (long)(Y))
diff = (cmp(bundle->peer, call->peer) ?:
cmp(bundle->key, call->key) ?:
cmp(bundle->security_level, call->security_level) ?:
cmp(bundle->upgrade, upgrade));
#undef cmp
if (diff < 0)
pp = &(*pp)->rb_left;
else if (diff > 0)
pp = &(*pp)->rb_right;
else
goto found_bundle_free;
}
_debug("new bundle");
rb_link_node(&candidate->local_node, parent, pp);
rb_insert_color(&candidate->local_node, &local->client_bundles);
call->bundle = rxrpc_get_bundle(candidate, rxrpc_bundle_get_client_call);
spin_unlock(&local->client_bundles_lock);
_leave(" = B=%u [new]", call->bundle->debug_id);
return 0;
found_bundle_free:
rxrpc_free_bundle(candidate);
found_bundle:
call->bundle = rxrpc_get_bundle(bundle, rxrpc_bundle_get_client_call);
rxrpc_activate_bundle(bundle);
spin_unlock(&local->client_bundles_lock);
_leave(" = B=%u [found]", call->bundle->debug_id);
return 0;
}
/*
* Allocate a new connection and add it into a bundle.
*/
static bool rxrpc_add_conn_to_bundle(struct rxrpc_bundle *bundle,
unsigned int slot)
{
struct rxrpc_connection *conn, *old;
unsigned int shift = slot * RXRPC_MAXCALLS;
unsigned int i;
old = bundle->conns[slot];
if (old) {
bundle->conns[slot] = NULL;
bundle->conn_ids[slot] = 0;
trace_rxrpc_client(old, -1, rxrpc_client_replace);
rxrpc_put_connection(old, rxrpc_conn_put_noreuse);
}
conn = rxrpc_alloc_client_connection(bundle);
if (IS_ERR(conn)) {
bundle->alloc_error = PTR_ERR(conn);
return false;
}
rxrpc_activate_bundle(bundle);
conn->bundle_shift = shift;
bundle->conns[slot] = conn;
bundle->conn_ids[slot] = conn->debug_id;
for (i = 0; i < RXRPC_MAXCALLS; i++)
set_bit(shift + i, &bundle->avail_chans);
return true;
}
/*
* Add a connection to a bundle if there are no usable connections or we have
* connections waiting for extra capacity.
*/
static bool rxrpc_bundle_has_space(struct rxrpc_bundle *bundle)
{
int slot = -1, i, usable;
_enter("");
bundle->alloc_error = 0;
/* See if there are any usable connections. */
usable = 0;
for (i = 0; i < ARRAY_SIZE(bundle->conns); i++) {
if (rxrpc_may_reuse_conn(bundle->conns[i]))
usable++;
else if (slot == -1)
slot = i;
}
if (!usable && bundle->upgrade)
bundle->try_upgrade = true;
if (!usable)
goto alloc_conn;
if (!bundle->avail_chans &&
!bundle->try_upgrade &&
usable < ARRAY_SIZE(bundle->conns))
goto alloc_conn;
_leave("");
return usable;
alloc_conn:
return slot >= 0 ? rxrpc_add_conn_to_bundle(bundle, slot) : false;
}
/*
* Assign a channel to the call at the front of the queue and wake the call up.
* We don't increment the callNumber counter until this number has been exposed
* to the world.
*/
static void rxrpc_activate_one_channel(struct rxrpc_connection *conn,
unsigned int channel)
{
struct rxrpc_channel *chan = &conn->channels[channel];
struct rxrpc_bundle *bundle = conn->bundle;
struct rxrpc_call *call = list_entry(bundle->waiting_calls.next,
struct rxrpc_call, wait_link);
u32 call_id = chan->call_counter + 1;
_enter("C=%x,%u", conn->debug_id, channel);
list_del_init(&call->wait_link);
trace_rxrpc_client(conn, channel, rxrpc_client_chan_activate);
/* Cancel the final ACK on the previous call if it hasn't been sent yet
* as the DATA packet will implicitly ACK it.
*/
clear_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags);
clear_bit(conn->bundle_shift + channel, &bundle->avail_chans);
rxrpc_see_call(call, rxrpc_call_see_activate_client);
call->conn = rxrpc_get_connection(conn, rxrpc_conn_get_activate_call);
call->cid = conn->proto.cid | channel;
call->call_id = call_id;
call->dest_srx.srx_service = conn->service_id;
call->cong_ssthresh = call->peer->cong_ssthresh;
if (call->cong_cwnd >= call->cong_ssthresh)
call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
else
call->cong_mode = RXRPC_CALL_SLOW_START;
chan->call_id = call_id;
chan->call_debug_id = call->debug_id;
chan->call = call;
rxrpc_see_call(call, rxrpc_call_see_connected);
trace_rxrpc_connect_call(call);
call->tx_last_sent = ktime_get_real();
rxrpc_start_call_timer(call);
rxrpc_set_call_state(call, RXRPC_CALL_CLIENT_SEND_REQUEST);
wake_up(&call->waitq);
}
/*
* Remove a connection from the idle list if it's on it.
*/
static void rxrpc_unidle_conn(struct rxrpc_connection *conn)
{
if (!list_empty(&conn->cache_link)) {
list_del_init(&conn->cache_link);
rxrpc_put_connection(conn, rxrpc_conn_put_unidle);
}
}
/*
* Assign channels and callNumbers to waiting calls.
*/
static void rxrpc_activate_channels(struct rxrpc_bundle *bundle)
{
struct rxrpc_connection *conn;
unsigned long avail, mask;
unsigned int channel, slot;
trace_rxrpc_client(NULL, -1, rxrpc_client_activate_chans);
if (bundle->try_upgrade)
mask = 1;
else
mask = ULONG_MAX;
while (!list_empty(&bundle->waiting_calls)) {
avail = bundle->avail_chans & mask;
if (!avail)
break;
channel = __ffs(avail);
clear_bit(channel, &bundle->avail_chans);
slot = channel / RXRPC_MAXCALLS;
conn = bundle->conns[slot];
if (!conn)
break;
if (bundle->try_upgrade)
set_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags);
rxrpc_unidle_conn(conn);
channel &= (RXRPC_MAXCALLS - 1);
conn->act_chans |= 1 << channel;
rxrpc_activate_one_channel(conn, channel);
}
}
/*
* Connect waiting channels (called from the I/O thread).
*/
void rxrpc_connect_client_calls(struct rxrpc_local *local)
{
struct rxrpc_call *call;
while ((call = list_first_entry_or_null(&local->new_client_calls,
struct rxrpc_call, wait_link))
) {
struct rxrpc_bundle *bundle = call->bundle;
spin_lock(&local->client_call_lock);
list_move_tail(&call->wait_link, &bundle->waiting_calls);
spin_unlock(&local->client_call_lock);
if (rxrpc_bundle_has_space(bundle))
rxrpc_activate_channels(bundle);
}
}
/*
* Note that a call, and thus a connection, is about to be exposed to the
* world.
*/
void rxrpc_expose_client_call(struct rxrpc_call *call)
{
unsigned int channel = call->cid & RXRPC_CHANNELMASK;
struct rxrpc_connection *conn = call->conn;
struct rxrpc_channel *chan = &conn->channels[channel];
if (!test_and_set_bit(RXRPC_CALL_EXPOSED, &call->flags)) {
/* Mark the call ID as being used. If the callNumber counter
* exceeds ~2 billion, we kill the connection after its
* outstanding calls have finished so that the counter doesn't
* wrap.
*/
chan->call_counter++;
if (chan->call_counter >= INT_MAX)
set_bit(RXRPC_CONN_DONT_REUSE, &conn->flags);
trace_rxrpc_client(conn, channel, rxrpc_client_exposed);
spin_lock(&call->peer->lock);
hlist_add_head(&call->error_link, &call->peer->error_targets);
spin_unlock(&call->peer->lock);
}
}
/*
* Set the reap timer.
*/
static void rxrpc_set_client_reap_timer(struct rxrpc_local *local)
{
if (!local->kill_all_client_conns) {
unsigned long now = jiffies;
unsigned long reap_at = now + rxrpc_conn_idle_client_expiry;
if (local->rxnet->live)
timer_reduce(&local->client_conn_reap_timer, reap_at);
}
}
/*
* Disconnect a client call.
*/
void rxrpc_disconnect_client_call(struct rxrpc_bundle *bundle, struct rxrpc_call *call)
{
struct rxrpc_connection *conn;
struct rxrpc_channel *chan = NULL;
struct rxrpc_local *local = bundle->local;
unsigned int channel;
bool may_reuse;
u32 cid;
_enter("c=%x", call->debug_id);
/* Calls that have never actually been assigned a channel can simply be
* discarded.
*/
conn = call->conn;
if (!conn) {
_debug("call is waiting");
ASSERTCMP(call->call_id, ==, 0);
ASSERT(!test_bit(RXRPC_CALL_EXPOSED, &call->flags));
list_del_init(&call->wait_link);
return;
}
cid = call->cid;
channel = cid & RXRPC_CHANNELMASK;
chan = &conn->channels[channel];
trace_rxrpc_client(conn, channel, rxrpc_client_chan_disconnect);
if (WARN_ON(chan->call != call))
return;
may_reuse = rxrpc_may_reuse_conn(conn);
/* If a client call was exposed to the world, we save the result for
* retransmission.
*
* We use a barrier here so that the call number and abort code can be
* read without needing to take a lock.
*
* TODO: Make the incoming packet handler check this and handle
* terminal retransmission without requiring access to the call.
*/
if (test_bit(RXRPC_CALL_EXPOSED, &call->flags)) {
_debug("exposed %u,%u", call->call_id, call->abort_code);
__rxrpc_disconnect_call(conn, call);
if (test_and_clear_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags)) {
trace_rxrpc_client(conn, channel, rxrpc_client_to_active);
bundle->try_upgrade = false;
if (may_reuse)
rxrpc_activate_channels(bundle);
}
}
/* See if we can pass the channel directly to another call. */
if (may_reuse && !list_empty(&bundle->waiting_calls)) {
trace_rxrpc_client(conn, channel, rxrpc_client_chan_pass);
rxrpc_activate_one_channel(conn, channel);
return;
}
/* Schedule the final ACK to be transmitted in a short while so that it
* can be skipped if we find a follow-on call. The first DATA packet
* of the follow on call will implicitly ACK this call.
*/
if (call->completion == RXRPC_CALL_SUCCEEDED &&
test_bit(RXRPC_CALL_EXPOSED, &call->flags)) {
unsigned long final_ack_at = jiffies + 2;
chan->final_ack_at = final_ack_at;
smp_wmb(); /* vs rxrpc_process_delayed_final_acks() */
set_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags);
rxrpc_reduce_conn_timer(conn, final_ack_at);
}
/* Deactivate the channel. */
chan->call = NULL;
set_bit(conn->bundle_shift + channel, &conn->bundle->avail_chans);
conn->act_chans &= ~(1 << channel);
/* If no channels remain active, then put the connection on the idle
* list for a short while. Give it a ref to stop it going away if it
* becomes unbundled.
*/
if (!conn->act_chans) {
trace_rxrpc_client(conn, channel, rxrpc_client_to_idle);
conn->idle_timestamp = jiffies;
rxrpc_get_connection(conn, rxrpc_conn_get_idle);
list_move_tail(&conn->cache_link, &local->idle_client_conns);
rxrpc_set_client_reap_timer(local);
}
}
/*
* Remove a connection from a bundle.
*/
static void rxrpc_unbundle_conn(struct rxrpc_connection *conn)
{
struct rxrpc_bundle *bundle = conn->bundle;
unsigned int bindex;
int i;
_enter("C=%x", conn->debug_id);
if (conn->flags & RXRPC_CONN_FINAL_ACK_MASK)
rxrpc_process_delayed_final_acks(conn, true);
bindex = conn->bundle_shift / RXRPC_MAXCALLS;
if (bundle->conns[bindex] == conn) {
_debug("clear slot %u", bindex);
bundle->conns[bindex] = NULL;
bundle->conn_ids[bindex] = 0;
for (i = 0; i < RXRPC_MAXCALLS; i++)
clear_bit(conn->bundle_shift + i, &bundle->avail_chans);
rxrpc_put_client_connection_id(bundle->local, conn);
rxrpc_deactivate_bundle(bundle);
rxrpc_put_connection(conn, rxrpc_conn_put_unbundle);
}
}
/*
* Drop the active count on a bundle.
*/
void rxrpc_deactivate_bundle(struct rxrpc_bundle *bundle)
{
struct rxrpc_local *local;
bool need_put = false;
if (!bundle)
return;
local = bundle->local;
if (atomic_dec_and_lock(&bundle->active, &local->client_bundles_lock)) {
if (!bundle->exclusive) {
_debug("erase bundle");
rb_erase(&bundle->local_node, &local->client_bundles);
need_put = true;
}
spin_unlock(&local->client_bundles_lock);
if (need_put)
rxrpc_put_bundle(bundle, rxrpc_bundle_put_discard);
}
}
/*
* Clean up a dead client connection.
*/
void rxrpc_kill_client_conn(struct rxrpc_connection *conn)
{
struct rxrpc_local *local = conn->local;
struct rxrpc_net *rxnet = local->rxnet;
_enter("C=%x", conn->debug_id);
trace_rxrpc_client(conn, -1, rxrpc_client_cleanup);
atomic_dec(&rxnet->nr_client_conns);
rxrpc_put_client_connection_id(local, conn);
}
/*
* Discard expired client connections from the idle list. Each conn in the
* idle list has been exposed and holds an extra ref because of that.
*
* This may be called from conn setup or from a work item so cannot be
* considered non-reentrant.
*/
void rxrpc_discard_expired_client_conns(struct rxrpc_local *local)
{
struct rxrpc_connection *conn;
unsigned long expiry, conn_expires_at, now;
unsigned int nr_conns;
_enter("");
/* We keep an estimate of what the number of conns ought to be after
* we've discarded some so that we don't overdo the discarding.
*/
nr_conns = atomic_read(&local->rxnet->nr_client_conns);
next:
conn = list_first_entry_or_null(&local->idle_client_conns,
struct rxrpc_connection, cache_link);
if (!conn)
return;
if (!local->kill_all_client_conns) {
/* If the number of connections is over the reap limit, we
* expedite discard by reducing the expiry timeout. We must,
* however, have at least a short grace period to be able to do
* final-ACK or ABORT retransmission.
*/
expiry = rxrpc_conn_idle_client_expiry;
if (nr_conns > rxrpc_reap_client_connections)
expiry = rxrpc_conn_idle_client_fast_expiry;
if (conn->local->service_closed)
expiry = rxrpc_closed_conn_expiry * HZ;
conn_expires_at = conn->idle_timestamp + expiry;
now = jiffies;
if (time_after(conn_expires_at, now))
goto not_yet_expired;
}
atomic_dec(&conn->active);
trace_rxrpc_client(conn, -1, rxrpc_client_discard);
list_del_init(&conn->cache_link);
rxrpc_unbundle_conn(conn);
/* Drop the ->cache_link ref */
rxrpc_put_connection(conn, rxrpc_conn_put_discard_idle);
nr_conns--;
goto next;
not_yet_expired:
/* The connection at the front of the queue hasn't yet expired, so
* schedule the work item for that point if we discarded something.
*
* We don't worry if the work item is already scheduled - it can look
* after rescheduling itself at a later time. We could cancel it, but
* then things get messier.
*/
_debug("not yet");
if (!local->kill_all_client_conns)
timer_reduce(&local->client_conn_reap_timer, conn_expires_at);
_leave("");
}
/*
* Clean up the client connections on a local endpoint.
*/
void rxrpc_clean_up_local_conns(struct rxrpc_local *local)
{
struct rxrpc_connection *conn;
_enter("");
local->kill_all_client_conns = true;
del_timer_sync(&local->client_conn_reap_timer);
while ((conn = list_first_entry_or_null(&local->idle_client_conns,
struct rxrpc_connection, cache_link))) {
list_del_init(&conn->cache_link);
atomic_dec(&conn->active);
trace_rxrpc_client(conn, -1, rxrpc_client_discard);
rxrpc_unbundle_conn(conn);
rxrpc_put_connection(conn, rxrpc_conn_put_local_dead);
}
_leave(" [culled]");
}
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