linux/net/rxrpc/call_object.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

632 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* RxRPC individual remote procedure call handling
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#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"
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_SERVER_PREALLOC] = "SvPrealc",
[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",
};
const char *const rxrpc_call_completions[NR__RXRPC_CALL_COMPLETIONS] = {
[RXRPC_CALL_SUCCEEDED] = "Complete",
[RXRPC_CALL_REMOTELY_ABORTED] = "RmtAbort",
[RXRPC_CALL_LOCALLY_ABORTED] = "LocAbort",
[RXRPC_CALL_LOCAL_ERROR] = "LocError",
[RXRPC_CALL_NETWORK_ERROR] = "NetError",
};
struct kmem_cache *rxrpc_call_jar;
static void rxrpc_call_timer_expired(struct timer_list *t)
{
struct rxrpc_call *call = from_timer(call, t, timer);
_enter("%d", call->debug_id);
if (call->state < RXRPC_CALL_COMPLETE) {
trace_rxrpc_timer(call, rxrpc_timer_expired, jiffies);
rxrpc_queue_call(call);
}
}
static struct lock_class_key rxrpc_call_user_mutex_lock_class_key;
/*
* 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, rxrpc_call_got);
read_unlock(&rx->call_lock);
_leave(" = %p [%d]", call, atomic_read(&call->usage));
return call;
}
/*
* allocate a new call
*/
struct rxrpc_call *rxrpc_alloc_call(struct rxrpc_sock *rx, gfp_t gfp,
unsigned int debug_id)
{
struct rxrpc_call *call;
struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
call = kmem_cache_zalloc(rxrpc_call_jar, gfp);
if (!call)
return NULL;
call->rxtx_buffer = kcalloc(RXRPC_RXTX_BUFF_SIZE,
sizeof(struct sk_buff *),
gfp);
if (!call->rxtx_buffer)
goto nomem;
call->rxtx_annotations = kcalloc(RXRPC_RXTX_BUFF_SIZE, sizeof(u8), gfp);
if (!call->rxtx_annotations)
goto nomem_2;
mutex_init(&call->user_mutex);
/* Prevent lockdep reporting a deadlock false positive between the afs
* filesystem and sys_sendmsg() via the mmap sem.
*/
if (rx->sk.sk_kern_sock)
lockdep_set_class(&call->user_mutex,
&rxrpc_call_user_mutex_lock_class_key);
timer_setup(&call->timer, rxrpc_call_timer_expired, 0);
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);
INIT_LIST_HEAD(&call->recvmsg_link);
INIT_LIST_HEAD(&call->sock_link);
init_waitqueue_head(&call->waitq);
spin_lock_init(&call->lock);
spin_lock_init(&call->notify_lock);
spin_lock_init(&call->input_lock);
rwlock_init(&call->state_lock);
atomic_set(&call->usage, 1);
call->debug_id = debug_id;
call->tx_total_len = -1;
call->next_rx_timo = 20 * HZ;
call->next_req_timo = 1 * HZ;
memset(&call->sock_node, 0xed, sizeof(call->sock_node));
/* Leave space in the ring to handle a maxed-out jumbo packet */
call->rx_winsize = rxrpc_rx_window_size;
call->tx_winsize = 16;
call->rx_expect_next = 1;
call->cong_cwnd = 2;
call->cong_ssthresh = RXRPC_RXTX_BUFF_SIZE - 1;
call->rxnet = rxnet;
atomic_inc(&rxnet->nr_calls);
return call;
nomem_2:
kfree(call->rxtx_buffer);
nomem:
kmem_cache_free(rxrpc_call_jar, call);
return NULL;
}
/*
* Allocate a new client call.
*/
static struct rxrpc_call *rxrpc_alloc_client_call(struct rxrpc_sock *rx,
struct sockaddr_rxrpc *srx,
gfp_t gfp,
unsigned int debug_id)
{
struct rxrpc_call *call;
ktime_t now;
_enter("");
call = rxrpc_alloc_call(rx, gfp, debug_id);
if (!call)
return ERR_PTR(-ENOMEM);
call->state = RXRPC_CALL_CLIENT_AWAIT_CONN;
call->service_id = srx->srx_service;
call->tx_phase = true;
now = ktime_get_real();
call->acks_latest_ts = now;
call->cong_tstamp = now;
_leave(" = %p", call);
return call;
}
/*
* Initiate the call ack/resend/expiry timer.
*/
static void rxrpc_start_call_timer(struct rxrpc_call *call)
{
unsigned long now = jiffies;
unsigned long j = now + MAX_JIFFY_OFFSET;
call->ack_at = j;
call->ack_lost_at = j;
call->resend_at = j;
call->ping_at = j;
call->expect_rx_by = j;
call->expect_req_by = j;
call->expect_term_by = j;
call->timer.expires = now;
}
/*
* Set up a call for the given parameters.
* - Called with the socket lock held, which it must release.
* - If it returns a call, the call's lock will need releasing by the caller.
*/
struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
struct rxrpc_conn_parameters *cp,
struct sockaddr_rxrpc *srx,
struct rxrpc_call_params *p,
gfp_t gfp,
unsigned int debug_id)
__releases(&rx->sk.sk_lock.slock)
__acquires(&call->user_mutex)
{
struct rxrpc_call *call, *xcall;
struct rxrpc_net *rxnet;
struct rb_node *parent, **pp;
const void *here = __builtin_return_address(0);
int ret;
_enter("%p,%lx", rx, p->user_call_ID);
call = rxrpc_alloc_client_call(rx, srx, gfp, debug_id);
if (IS_ERR(call)) {
release_sock(&rx->sk);
_leave(" = %ld", PTR_ERR(call));
return call;
}
if (p->intr)
__set_bit(RXRPC_CALL_IS_INTR, &call->flags);
call->tx_total_len = p->tx_total_len;
trace_rxrpc_call(call, rxrpc_call_new_client, atomic_read(&call->usage),
here, (const void *)p->user_call_ID);
/* We need to protect a partially set up call against the user as we
* will be acting outside the socket lock.
*/
mutex_lock(&call->user_mutex);
/* Publish the call, even though it is incompletely set up as yet */
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 (p->user_call_ID < xcall->user_call_ID)
pp = &(*pp)->rb_left;
else if (p->user_call_ID > xcall->user_call_ID)
pp = &(*pp)->rb_right;
else
goto error_dup_user_ID;
}
rcu_assign_pointer(call->socket, rx);
call->user_call_ID = p->user_call_ID;
__set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
rxrpc_get_call(call, rxrpc_call_got_userid);
rb_link_node(&call->sock_node, parent, pp);
rb_insert_color(&call->sock_node, &rx->calls);
list_add(&call->sock_link, &rx->sock_calls);
write_unlock(&rx->call_lock);
rxnet = call->rxnet;
write_lock(&rxnet->call_lock);
list_add_tail(&call->link, &rxnet->calls);
write_unlock(&rxnet->call_lock);
/* From this point on, the call is protected by its own lock. */
release_sock(&rx->sk);
/* Set up or get a connection record and set the protocol parameters,
* including channel number and call ID.
*/
ret = rxrpc_connect_call(rx, call, cp, srx, gfp);
if (ret < 0)
goto error;
trace_rxrpc_call(call, rxrpc_call_connected, atomic_read(&call->usage),
here, NULL);
rxrpc_start_call_timer(call);
_net("CALL new %d on CONN %d", call->debug_id, call->conn->debug_id);
_leave(" = %p [new]", call);
return call;
/* 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.
*/
error_dup_user_ID:
write_unlock(&rx->call_lock);
release_sock(&rx->sk);
ret = -EEXIST;
error:
__rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
RX_CALL_DEAD, ret);
trace_rxrpc_call(call, rxrpc_call_error, atomic_read(&call->usage),
here, ERR_PTR(ret));
rxrpc_release_call(rx, call);
mutex_unlock(&call->user_mutex);
rxrpc_put_call(call, rxrpc_call_put);
_leave(" = %d", ret);
return ERR_PTR(ret);
}
/*
* Set up an incoming call. call->conn points to the connection.
* This is called in BH context and isn't allowed to fail.
*/
void rxrpc_incoming_call(struct rxrpc_sock *rx,
struct rxrpc_call *call,
struct sk_buff *skb)
{
struct rxrpc_connection *conn = call->conn;
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
u32 chan;
_enter(",%d", call->conn->debug_id);
rcu_assign_pointer(call->socket, rx);
call->call_id = sp->hdr.callNumber;
call->service_id = sp->hdr.serviceId;
call->cid = sp->hdr.cid;
call->state = RXRPC_CALL_SERVER_ACCEPTING;
if (sp->hdr.securityIndex > 0)
call->state = RXRPC_CALL_SERVER_SECURING;
call->cong_tstamp = skb->tstamp;
/* Set the channel for this call. We don't get channel_lock as we're
* only defending against the data_ready handler (which we're called
* from) and the RESPONSE packet parser (which is only really
* interested in call_counter and can cope with a disagreement with the
* call pointer).
*/
chan = sp->hdr.cid & RXRPC_CHANNELMASK;
conn->channels[chan].call_counter = call->call_id;
conn->channels[chan].call_id = call->call_id;
rcu_assign_pointer(conn->channels[chan].call, call);
spin_lock(&conn->params.peer->lock);
hlist_add_head_rcu(&call->error_link, &conn->params.peer->error_targets);
spin_unlock(&conn->params.peer->lock);
_net("CALL incoming %d on CONN %d", call->debug_id, call->conn->debug_id);
rxrpc_start_call_timer(call);
_leave("");
}
/*
* Queue a call's work processor, getting a ref to pass to the work queue.
*/
bool rxrpc_queue_call(struct rxrpc_call *call)
{
const void *here = __builtin_return_address(0);
int n = atomic_fetch_add_unless(&call->usage, 1, 0);
if (n == 0)
return false;
if (rxrpc_queue_work(&call->processor))
trace_rxrpc_call(call, rxrpc_call_queued, n + 1, here, NULL);
else
rxrpc_put_call(call, rxrpc_call_put_noqueue);
return true;
}
/*
* Queue a call's work processor, passing the callers ref to the work queue.
*/
bool __rxrpc_queue_call(struct rxrpc_call *call)
{
const void *here = __builtin_return_address(0);
int n = atomic_read(&call->usage);
ASSERTCMP(n, >=, 1);
if (rxrpc_queue_work(&call->processor))
trace_rxrpc_call(call, rxrpc_call_queued_ref, n, here, NULL);
else
rxrpc_put_call(call, rxrpc_call_put_noqueue);
return true;
}
/*
* Note the re-emergence of a call.
*/
void rxrpc_see_call(struct rxrpc_call *call)
{
const void *here = __builtin_return_address(0);
if (call) {
int n = atomic_read(&call->usage);
trace_rxrpc_call(call, rxrpc_call_seen, n, here, NULL);
}
}
/*
* Note the addition of a ref on a call.
*/
void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
{
const void *here = __builtin_return_address(0);
int n = atomic_inc_return(&call->usage);
trace_rxrpc_call(call, op, n, here, NULL);
}
/*
* Detach a call from its owning socket.
*/
void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
{
const void *here = __builtin_return_address(0);
struct rxrpc_connection *conn = call->conn;
bool put = false;
int i;
_enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
trace_rxrpc_call(call, rxrpc_call_release, atomic_read(&call->usage),
here, (const void *)call->flags);
ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
spin_lock_bh(&call->lock);
if (test_and_set_bit(RXRPC_CALL_RELEASED, &call->flags))
BUG();
spin_unlock_bh(&call->lock);
del_timer_sync(&call->timer);
/* Make sure we don't get any more notifications */
write_lock_bh(&rx->recvmsg_lock);
if (!list_empty(&call->recvmsg_link)) {
_debug("unlinking once-pending call %p { e=%lx f=%lx }",
call, call->events, call->flags);
list_del(&call->recvmsg_link);
put = true;
}
/* list_empty() must return false in rxrpc_notify_socket() */
call->recvmsg_link.next = NULL;
call->recvmsg_link.prev = NULL;
write_unlock_bh(&rx->recvmsg_lock);
if (put)
rxrpc_put_call(call, rxrpc_call_put);
write_lock(&rx->call_lock);
if (test_and_clear_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
rb_erase(&call->sock_node, &rx->calls);
memset(&call->sock_node, 0xdd, sizeof(call->sock_node));
rxrpc_put_call(call, rxrpc_call_put_userid);
}
list_del(&call->sock_link);
write_unlock(&rx->call_lock);
_debug("RELEASE CALL %p (%d CONN %p)", call, call->debug_id, conn);
if (conn)
rxrpc_disconnect_call(call);
for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
rxrpc_free_skb(call->rxtx_buffer[i],
(call->tx_phase ? rxrpc_skb_tx_cleaned :
rxrpc_skb_rx_cleaned));
call->rxtx_buffer[i] = NULL;
}
_leave("");
}
/*
* release all the calls associated with a socket
*/
void rxrpc_release_calls_on_socket(struct rxrpc_sock *rx)
{
struct rxrpc_call *call;
_enter("%p", rx);
while (!list_empty(&rx->to_be_accepted)) {
call = list_entry(rx->to_be_accepted.next,
struct rxrpc_call, accept_link);
list_del(&call->accept_link);
rxrpc_abort_call("SKR", call, 0, RX_CALL_DEAD, -ECONNRESET);
rxrpc_put_call(call, rxrpc_call_put);
}
while (!list_empty(&rx->sock_calls)) {
call = list_entry(rx->sock_calls.next,
struct rxrpc_call, sock_link);
rxrpc_get_call(call, rxrpc_call_got);
rxrpc_abort_call("SKT", call, 0, RX_CALL_DEAD, -ECONNRESET);
rxrpc_send_abort_packet(call);
rxrpc_release_call(rx, call);
rxrpc_put_call(call, rxrpc_call_put);
}
_leave("");
}
/*
* release a call
*/
void rxrpc_put_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
{
struct rxrpc_net *rxnet = call->rxnet;
const void *here = __builtin_return_address(0);
int n;
ASSERT(call != NULL);
n = atomic_dec_return(&call->usage);
trace_rxrpc_call(call, op, n, here, NULL);
ASSERTCMP(n, >=, 0);
if (n == 0) {
_debug("call %d dead", call->debug_id);
ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
if (!list_empty(&call->link)) {
write_lock(&rxnet->call_lock);
list_del_init(&call->link);
write_unlock(&rxnet->call_lock);
}
rxrpc_cleanup_call(call);
}
}
/*
* 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);
struct rxrpc_net *rxnet = call->rxnet;
rxrpc_put_peer(call->peer);
kfree(call->rxtx_buffer);
kfree(call->rxtx_annotations);
kmem_cache_free(rxrpc_call_jar, call);
if (atomic_dec_and_test(&rxnet->nr_calls))
wake_up_var(&rxnet->nr_calls);
}
/*
* clean up a call
*/
void rxrpc_cleanup_call(struct rxrpc_call *call)
{
int i;
_net("DESTROY CALL %d", call->debug_id);
memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
del_timer_sync(&call->timer);
ASSERTCMP(call->state, ==, RXRPC_CALL_COMPLETE);
ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
ASSERTCMP(call->conn, ==, NULL);
/* Clean up the Rx/Tx buffer */
for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++)
rxrpc_free_skb(call->rxtx_buffer[i],
(call->tx_phase ? rxrpc_skb_tx_cleaned :
rxrpc_skb_rx_cleaned));
rxrpc_free_skb(call->tx_pending, rxrpc_skb_tx_cleaned);
call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
}
/*
* Make sure that all calls are gone from a network namespace. To reach this
* point, any open UDP sockets in that namespace must have been closed, so any
* outstanding calls cannot be doing I/O.
*/
void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
{
struct rxrpc_call *call;
_enter("");
if (!list_empty(&rxnet->calls)) {
write_lock(&rxnet->call_lock);
while (!list_empty(&rxnet->calls)) {
call = list_entry(rxnet->calls.next,
struct rxrpc_call, link);
_debug("Zapping call %p", call);
rxrpc_see_call(call);
list_del_init(&call->link);
pr_err("Call %p still in use (%d,%s,%lx,%lx)!\n",
call, atomic_read(&call->usage),
rxrpc_call_states[call->state],
call->flags, call->events);
write_unlock(&rxnet->call_lock);
cond_resched();
write_lock(&rxnet->call_lock);
}
write_unlock(&rxnet->call_lock);
}
atomic_dec(&rxnet->nr_calls);
wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
}