| /* 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" |
| |
| 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)); |
| } |