/* * net/tipc/link.c: TIPC link code * * Copyright (c) 1996-2007, 2012-2014, Ericsson AB * Copyright (c) 2004-2007, 2010-2013, Wind River Systems * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the names of the copyright holders nor the names of its * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * Alternatively, this software may be distributed under the terms of the * GNU General Public License ("GPL") version 2 as published by the Free * Software Foundation. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include "core.h" #include "link.h" #include "port.h" #include "name_distr.h" #include "discover.h" #include "config.h" #include /* * Error message prefixes */ static const char *link_co_err = "Link changeover error, "; static const char *link_rst_msg = "Resetting link "; static const char *link_unk_evt = "Unknown link event "; /* * Out-of-range value for link session numbers */ #define INVALID_SESSION 0x10000 /* * Link state events: */ #define STARTING_EVT 856384768 /* link processing trigger */ #define TRAFFIC_MSG_EVT 560815u /* rx'd ??? */ #define TIMEOUT_EVT 560817u /* link timer expired */ /* * The following two 'message types' is really just implementation * data conveniently stored in the message header. * They must not be considered part of the protocol */ #define OPEN_MSG 0 #define CLOSED_MSG 1 /* * State value stored in 'exp_msg_count' */ #define START_CHANGEOVER 100000u static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr, struct sk_buff *buf); static void link_recv_proto_msg(struct tipc_link *l_ptr, struct sk_buff *buf); static int tipc_link_tunnel_rcv(struct tipc_node *n_ptr, struct sk_buff **buf); static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance); static int link_send_sections_long(struct tipc_port *sender, struct iovec const *msg_sect, unsigned int len, u32 destnode); static void link_state_event(struct tipc_link *l_ptr, u32 event); static void link_reset_statistics(struct tipc_link *l_ptr); static void link_print(struct tipc_link *l_ptr, const char *str); static int link_send_long_buf(struct tipc_link *l_ptr, struct sk_buff *buf); static void tipc_link_send_sync(struct tipc_link *l); static void tipc_link_recv_sync(struct tipc_node *n, struct sk_buff *buf); /* * Simple link routines */ static unsigned int align(unsigned int i) { return (i + 3) & ~3u; } static void link_init_max_pkt(struct tipc_link *l_ptr) { u32 max_pkt; max_pkt = (l_ptr->b_ptr->mtu & ~3); if (max_pkt > MAX_MSG_SIZE) max_pkt = MAX_MSG_SIZE; l_ptr->max_pkt_target = max_pkt; if (l_ptr->max_pkt_target < MAX_PKT_DEFAULT) l_ptr->max_pkt = l_ptr->max_pkt_target; else l_ptr->max_pkt = MAX_PKT_DEFAULT; l_ptr->max_pkt_probes = 0; } static u32 link_next_sent(struct tipc_link *l_ptr) { if (l_ptr->next_out) return buf_seqno(l_ptr->next_out); return mod(l_ptr->next_out_no); } static u32 link_last_sent(struct tipc_link *l_ptr) { return mod(link_next_sent(l_ptr) - 1); } /* * Simple non-static link routines (i.e. referenced outside this file) */ int tipc_link_is_up(struct tipc_link *l_ptr) { if (!l_ptr) return 0; return link_working_working(l_ptr) || link_working_unknown(l_ptr); } int tipc_link_is_active(struct tipc_link *l_ptr) { return (l_ptr->owner->active_links[0] == l_ptr) || (l_ptr->owner->active_links[1] == l_ptr); } /** * link_timeout - handle expiration of link timer * @l_ptr: pointer to link */ static void link_timeout(struct tipc_link *l_ptr) { tipc_node_lock(l_ptr->owner); /* update counters used in statistical profiling of send traffic */ l_ptr->stats.accu_queue_sz += l_ptr->out_queue_size; l_ptr->stats.queue_sz_counts++; if (l_ptr->first_out) { struct tipc_msg *msg = buf_msg(l_ptr->first_out); u32 length = msg_size(msg); if ((msg_user(msg) == MSG_FRAGMENTER) && (msg_type(msg) == FIRST_FRAGMENT)) { length = msg_size(msg_get_wrapped(msg)); } if (length) { l_ptr->stats.msg_lengths_total += length; l_ptr->stats.msg_length_counts++; if (length <= 64) l_ptr->stats.msg_length_profile[0]++; else if (length <= 256) l_ptr->stats.msg_length_profile[1]++; else if (length <= 1024) l_ptr->stats.msg_length_profile[2]++; else if (length <= 4096) l_ptr->stats.msg_length_profile[3]++; else if (length <= 16384) l_ptr->stats.msg_length_profile[4]++; else if (length <= 32768) l_ptr->stats.msg_length_profile[5]++; else l_ptr->stats.msg_length_profile[6]++; } } /* do all other link processing performed on a periodic basis */ link_state_event(l_ptr, TIMEOUT_EVT); if (l_ptr->next_out) tipc_link_push_queue(l_ptr); tipc_node_unlock(l_ptr->owner); } static void link_set_timer(struct tipc_link *l_ptr, u32 time) { k_start_timer(&l_ptr->timer, time); } /** * tipc_link_create - create a new link * @n_ptr: pointer to associated node * @b_ptr: pointer to associated bearer * @media_addr: media address to use when sending messages over link * * Returns pointer to link. */ struct tipc_link *tipc_link_create(struct tipc_node *n_ptr, struct tipc_bearer *b_ptr, const struct tipc_media_addr *media_addr) { struct tipc_link *l_ptr; struct tipc_msg *msg; char *if_name; char addr_string[16]; u32 peer = n_ptr->addr; if (n_ptr->link_cnt >= 2) { tipc_addr_string_fill(addr_string, n_ptr->addr); pr_err("Attempt to establish third link to %s\n", addr_string); return NULL; } if (n_ptr->links[b_ptr->identity]) { tipc_addr_string_fill(addr_string, n_ptr->addr); pr_err("Attempt to establish second link on <%s> to %s\n", b_ptr->name, addr_string); return NULL; } l_ptr = kzalloc(sizeof(*l_ptr), GFP_ATOMIC); if (!l_ptr) { pr_warn("Link creation failed, no memory\n"); return NULL; } l_ptr->addr = peer; if_name = strchr(b_ptr->name, ':') + 1; sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:unknown", tipc_zone(tipc_own_addr), tipc_cluster(tipc_own_addr), tipc_node(tipc_own_addr), if_name, tipc_zone(peer), tipc_cluster(peer), tipc_node(peer)); /* note: peer i/f name is updated by reset/activate message */ memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr)); l_ptr->owner = n_ptr; l_ptr->checkpoint = 1; l_ptr->peer_session = INVALID_SESSION; l_ptr->b_ptr = b_ptr; link_set_supervision_props(l_ptr, b_ptr->tolerance); l_ptr->state = RESET_UNKNOWN; l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg; msg = l_ptr->pmsg; tipc_msg_init(msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, l_ptr->addr); msg_set_size(msg, sizeof(l_ptr->proto_msg)); msg_set_session(msg, (tipc_random & 0xffff)); msg_set_bearer_id(msg, b_ptr->identity); strcpy((char *)msg_data(msg), if_name); l_ptr->priority = b_ptr->priority; tipc_link_set_queue_limits(l_ptr, b_ptr->window); link_init_max_pkt(l_ptr); l_ptr->next_out_no = 1; INIT_LIST_HEAD(&l_ptr->waiting_ports); link_reset_statistics(l_ptr); tipc_node_attach_link(n_ptr, l_ptr); k_init_timer(&l_ptr->timer, (Handler)link_timeout, (unsigned long)l_ptr); link_state_event(l_ptr, STARTING_EVT); return l_ptr; } void tipc_link_delete_list(unsigned int bearer_id, bool shutting_down) { struct tipc_link *l_ptr; struct tipc_node *n_ptr; list_for_each_entry(n_ptr, &tipc_node_list, list) { spin_lock_bh(&n_ptr->lock); l_ptr = n_ptr->links[bearer_id]; if (l_ptr) { tipc_link_reset(l_ptr); if (shutting_down || !tipc_node_is_up(n_ptr)) { tipc_node_detach_link(l_ptr->owner, l_ptr); tipc_link_reset_fragments(l_ptr); spin_unlock_bh(&n_ptr->lock); /* Nobody else can access this link now: */ del_timer_sync(&l_ptr->timer); kfree(l_ptr); } else { /* Detach/delete when failover is finished: */ l_ptr->flags |= LINK_STOPPED; spin_unlock_bh(&n_ptr->lock); del_timer_sync(&l_ptr->timer); } continue; } spin_unlock_bh(&n_ptr->lock); } } /** * link_schedule_port - schedule port for deferred sending * @l_ptr: pointer to link * @origport: reference to sending port * @sz: amount of data to be sent * * Schedules port for renewed sending of messages after link congestion * has abated. */ static int link_schedule_port(struct tipc_link *l_ptr, u32 origport, u32 sz) { struct tipc_port *p_ptr; spin_lock_bh(&tipc_port_list_lock); p_ptr = tipc_port_lock(origport); if (p_ptr) { if (!p_ptr->wakeup) goto exit; if (!list_empty(&p_ptr->wait_list)) goto exit; p_ptr->congested = 1; p_ptr->waiting_pkts = 1 + ((sz - 1) / l_ptr->max_pkt); list_add_tail(&p_ptr->wait_list, &l_ptr->waiting_ports); l_ptr->stats.link_congs++; exit: tipc_port_unlock(p_ptr); } spin_unlock_bh(&tipc_port_list_lock); return -ELINKCONG; } void tipc_link_wakeup_ports(struct tipc_link *l_ptr, int all) { struct tipc_port *p_ptr; struct tipc_port *temp_p_ptr; int win = l_ptr->queue_limit[0] - l_ptr->out_queue_size; if (all) win = 100000; if (win <= 0) return; if (!spin_trylock_bh(&tipc_port_list_lock)) return; if (link_congested(l_ptr)) goto exit; list_for_each_entry_safe(p_ptr, temp_p_ptr, &l_ptr->waiting_ports, wait_list) { if (win <= 0) break; list_del_init(&p_ptr->wait_list); spin_lock_bh(p_ptr->lock); p_ptr->congested = 0; p_ptr->wakeup(p_ptr); win -= p_ptr->waiting_pkts; spin_unlock_bh(p_ptr->lock); } exit: spin_unlock_bh(&tipc_port_list_lock); } /** * link_release_outqueue - purge link's outbound message queue * @l_ptr: pointer to link */ static void link_release_outqueue(struct tipc_link *l_ptr) { kfree_skb_list(l_ptr->first_out); l_ptr->first_out = NULL; l_ptr->out_queue_size = 0; } /** * tipc_link_reset_fragments - purge link's inbound message fragments queue * @l_ptr: pointer to link */ void tipc_link_reset_fragments(struct tipc_link *l_ptr) { kfree_skb(l_ptr->reasm_head); l_ptr->reasm_head = NULL; l_ptr->reasm_tail = NULL; } /** * tipc_link_purge_queues - purge all pkt queues associated with link * @l_ptr: pointer to link */ void tipc_link_purge_queues(struct tipc_link *l_ptr) { kfree_skb_list(l_ptr->oldest_deferred_in); kfree_skb_list(l_ptr->first_out); tipc_link_reset_fragments(l_ptr); kfree_skb(l_ptr->proto_msg_queue); l_ptr->proto_msg_queue = NULL; } void tipc_link_reset(struct tipc_link *l_ptr) { u32 prev_state = l_ptr->state; u32 checkpoint = l_ptr->next_in_no; int was_active_link = tipc_link_is_active(l_ptr); msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff)); /* Link is down, accept any session */ l_ptr->peer_session = INVALID_SESSION; /* Prepare for max packet size negotiation */ link_init_max_pkt(l_ptr); l_ptr->state = RESET_UNKNOWN; if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET)) return; tipc_node_link_down(l_ptr->owner, l_ptr); tipc_bearer_remove_dest(l_ptr->b_ptr, l_ptr->addr); if (was_active_link && tipc_node_active_links(l_ptr->owner)) { l_ptr->reset_checkpoint = checkpoint; l_ptr->exp_msg_count = START_CHANGEOVER; } /* Clean up all queues: */ link_release_outqueue(l_ptr); kfree_skb(l_ptr->proto_msg_queue); l_ptr->proto_msg_queue = NULL; kfree_skb_list(l_ptr->oldest_deferred_in); if (!list_empty(&l_ptr->waiting_ports)) tipc_link_wakeup_ports(l_ptr, 1); l_ptr->retransm_queue_head = 0; l_ptr->retransm_queue_size = 0; l_ptr->last_out = NULL; l_ptr->first_out = NULL; l_ptr->next_out = NULL; l_ptr->unacked_window = 0; l_ptr->checkpoint = 1; l_ptr->next_out_no = 1; l_ptr->deferred_inqueue_sz = 0; l_ptr->oldest_deferred_in = NULL; l_ptr->newest_deferred_in = NULL; l_ptr->fsm_msg_cnt = 0; l_ptr->stale_count = 0; link_reset_statistics(l_ptr); } void tipc_link_reset_list(unsigned int bearer_id) { struct tipc_link *l_ptr; struct tipc_node *n_ptr; list_for_each_entry(n_ptr, &tipc_node_list, list) { spin_lock_bh(&n_ptr->lock); l_ptr = n_ptr->links[bearer_id]; if (l_ptr) tipc_link_reset(l_ptr); spin_unlock_bh(&n_ptr->lock); } } static void link_activate(struct tipc_link *l_ptr) { l_ptr->next_in_no = l_ptr->stats.recv_info = 1; tipc_node_link_up(l_ptr->owner, l_ptr); tipc_bearer_add_dest(l_ptr->b_ptr, l_ptr->addr); } /** * link_state_event - link finite state machine * @l_ptr: pointer to link * @event: state machine event to process */ static void link_state_event(struct tipc_link *l_ptr, unsigned int event) { struct tipc_link *other; u32 cont_intv = l_ptr->continuity_interval; if (l_ptr->flags & LINK_STOPPED) return; if (!(l_ptr->flags & LINK_STARTED) && (event != STARTING_EVT)) return; /* Not yet. */ /* Check whether changeover is going on */ if (l_ptr->exp_msg_count) { if (event == TIMEOUT_EVT) link_set_timer(l_ptr, cont_intv); return; } switch (l_ptr->state) { case WORKING_WORKING: switch (event) { case TRAFFIC_MSG_EVT: case ACTIVATE_MSG: break; case TIMEOUT_EVT: if (l_ptr->next_in_no != l_ptr->checkpoint) { l_ptr->checkpoint = l_ptr->next_in_no; if (tipc_bclink_acks_missing(l_ptr->owner)) { tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; } else if (l_ptr->max_pkt < l_ptr->max_pkt_target) { tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; } link_set_timer(l_ptr, cont_intv); break; } l_ptr->state = WORKING_UNKNOWN; l_ptr->fsm_msg_cnt = 0; tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; link_set_timer(l_ptr, cont_intv / 4); break; case RESET_MSG: pr_info("%s<%s>, requested by peer\n", link_rst_msg, l_ptr->name); tipc_link_reset(l_ptr); l_ptr->state = RESET_RESET; l_ptr->fsm_msg_cnt = 0; tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; link_set_timer(l_ptr, cont_intv); break; default: pr_err("%s%u in WW state\n", link_unk_evt, event); } break; case WORKING_UNKNOWN: switch (event) { case TRAFFIC_MSG_EVT: case ACTIVATE_MSG: l_ptr->state = WORKING_WORKING; l_ptr->fsm_msg_cnt = 0; link_set_timer(l_ptr, cont_intv); break; case RESET_MSG: pr_info("%s<%s>, requested by peer while probing\n", link_rst_msg, l_ptr->name); tipc_link_reset(l_ptr); l_ptr->state = RESET_RESET; l_ptr->fsm_msg_cnt = 0; tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; link_set_timer(l_ptr, cont_intv); break; case TIMEOUT_EVT: if (l_ptr->next_in_no != l_ptr->checkpoint) { l_ptr->state = WORKING_WORKING; l_ptr->fsm_msg_cnt = 0; l_ptr->checkpoint = l_ptr->next_in_no; if (tipc_bclink_acks_missing(l_ptr->owner)) { tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; } link_set_timer(l_ptr, cont_intv); } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) { tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; link_set_timer(l_ptr, cont_intv / 4); } else { /* Link has failed */ pr_warn("%s<%s>, peer not responding\n", link_rst_msg, l_ptr->name); tipc_link_reset(l_ptr); l_ptr->state = RESET_UNKNOWN; l_ptr->fsm_msg_cnt = 0; tipc_link_send_proto_msg(l_ptr, RESET_MSG, 0, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; link_set_timer(l_ptr, cont_intv); } break; default: pr_err("%s%u in WU state\n", link_unk_evt, event); } break; case RESET_UNKNOWN: switch (event) { case TRAFFIC_MSG_EVT: break; case ACTIVATE_MSG: other = l_ptr->owner->active_links[0]; if (other && link_working_unknown(other)) break; l_ptr->state = WORKING_WORKING; l_ptr->fsm_msg_cnt = 0; link_activate(l_ptr); tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; if (l_ptr->owner->working_links == 1) tipc_link_send_sync(l_ptr); link_set_timer(l_ptr, cont_intv); break; case RESET_MSG: l_ptr->state = RESET_RESET; l_ptr->fsm_msg_cnt = 0; tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 1, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; link_set_timer(l_ptr, cont_intv); break; case STARTING_EVT: l_ptr->flags |= LINK_STARTED; /* fall through */ case TIMEOUT_EVT: tipc_link_send_proto_msg(l_ptr, RESET_MSG, 0, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; link_set_timer(l_ptr, cont_intv); break; default: pr_err("%s%u in RU state\n", link_unk_evt, event); } break; case RESET_RESET: switch (event) { case TRAFFIC_MSG_EVT: case ACTIVATE_MSG: other = l_ptr->owner->active_links[0]; if (other && link_working_unknown(other)) break; l_ptr->state = WORKING_WORKING; l_ptr->fsm_msg_cnt = 0; link_activate(l_ptr); tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; if (l_ptr->owner->working_links == 1) tipc_link_send_sync(l_ptr); link_set_timer(l_ptr, cont_intv); break; case RESET_MSG: break; case TIMEOUT_EVT: tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0); l_ptr->fsm_msg_cnt++; link_set_timer(l_ptr, cont_intv); break; default: pr_err("%s%u in RR state\n", link_unk_evt, event); } break; default: pr_err("Unknown link state %u/%u\n", l_ptr->state, event); } } /* * link_bundle_buf(): Append contents of a buffer to * the tail of an existing one. */ static int link_bundle_buf(struct tipc_link *l_ptr, struct sk_buff *bundler, struct sk_buff *buf) { struct tipc_msg *bundler_msg = buf_msg(bundler); struct tipc_msg *msg = buf_msg(buf); u32 size = msg_size(msg); u32 bundle_size = msg_size(bundler_msg); u32 to_pos = align(bundle_size); u32 pad = to_pos - bundle_size; if (msg_user(bundler_msg) != MSG_BUNDLER) return 0; if (msg_type(bundler_msg) != OPEN_MSG) return 0; if (skb_tailroom(bundler) < (pad + size)) return 0; if (l_ptr->max_pkt < (to_pos + size)) return 0; skb_put(bundler, pad + size); skb_copy_to_linear_data_offset(bundler, to_pos, buf->data, size); msg_set_size(bundler_msg, to_pos + size); msg_set_msgcnt(bundler_msg, msg_msgcnt(bundler_msg) + 1); kfree_skb(buf); l_ptr->stats.sent_bundled++; return 1; } static void link_add_to_outqueue(struct tipc_link *l_ptr, struct sk_buff *buf, struct tipc_msg *msg) { u32 ack = mod(l_ptr->next_in_no - 1); u32 seqno = mod(l_ptr->next_out_no++); msg_set_word(msg, 2, ((ack << 16) | seqno)); msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); buf->next = NULL; if (l_ptr->first_out) { l_ptr->last_out->next = buf; l_ptr->last_out = buf; } else l_ptr->first_out = l_ptr->last_out = buf; l_ptr->out_queue_size++; if (l_ptr->out_queue_size > l_ptr->stats.max_queue_sz) l_ptr->stats.max_queue_sz = l_ptr->out_queue_size; } static void link_add_chain_to_outqueue(struct tipc_link *l_ptr, struct sk_buff *buf_chain, u32 long_msgno) { struct sk_buff *buf; struct tipc_msg *msg; if (!l_ptr->next_out) l_ptr->next_out = buf_chain; while (buf_chain) { buf = buf_chain; buf_chain = buf_chain->next; msg = buf_msg(buf); msg_set_long_msgno(msg, long_msgno); link_add_to_outqueue(l_ptr, buf, msg); } } /* * tipc_link_send_buf() is the 'full path' for messages, called from * inside TIPC when the 'fast path' in tipc_send_buf * has failed, and from link_send() */ int tipc_link_send_buf(struct tipc_link *l_ptr, struct sk_buff *buf) { struct tipc_msg *msg = buf_msg(buf); u32 size = msg_size(msg); u32 dsz = msg_data_sz(msg); u32 queue_size = l_ptr->out_queue_size; u32 imp = tipc_msg_tot_importance(msg); u32 queue_limit = l_ptr->queue_limit[imp]; u32 max_packet = l_ptr->max_pkt; /* Match msg importance against queue limits: */ if (unlikely(queue_size >= queue_limit)) { if (imp <= TIPC_CRITICAL_IMPORTANCE) { link_schedule_port(l_ptr, msg_origport(msg), size); kfree_skb(buf); return -ELINKCONG; } kfree_skb(buf); if (imp > CONN_MANAGER) { pr_warn("%s<%s>, send queue full", link_rst_msg, l_ptr->name); tipc_link_reset(l_ptr); } return dsz; } /* Fragmentation needed ? */ if (size > max_packet) return link_send_long_buf(l_ptr, buf); /* Packet can be queued or sent. */ if (likely(!link_congested(l_ptr))) { link_add_to_outqueue(l_ptr, buf, msg); tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr); l_ptr->unacked_window = 0; return dsz; } /* Congestion: can message be bundled ? */ if ((msg_user(msg) != CHANGEOVER_PROTOCOL) && (msg_user(msg) != MSG_FRAGMENTER)) { /* Try adding message to an existing bundle */ if (l_ptr->next_out && link_bundle_buf(l_ptr, l_ptr->last_out, buf)) return dsz; /* Try creating a new bundle */ if (size <= max_packet * 2 / 3) { struct sk_buff *bundler = tipc_buf_acquire(max_packet); struct tipc_msg bundler_hdr; if (bundler) { tipc_msg_init(&bundler_hdr, MSG_BUNDLER, OPEN_MSG, INT_H_SIZE, l_ptr->addr); skb_copy_to_linear_data(bundler, &bundler_hdr, INT_H_SIZE); skb_trim(bundler, INT_H_SIZE); link_bundle_buf(l_ptr, bundler, buf); buf = bundler; msg = buf_msg(buf); l_ptr->stats.sent_bundles++; } } } if (!l_ptr->next_out) l_ptr->next_out = buf; link_add_to_outqueue(l_ptr, buf, msg); return dsz; } /* * tipc_link_send(): same as tipc_link_send_buf(), but the link to use has * not been selected yet, and the the owner node is not locked * Called by TIPC internal users, e.g. the name distributor */ int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector) { struct tipc_link *l_ptr; struct tipc_node *n_ptr; int res = -ELINKCONG; read_lock_bh(&tipc_net_lock); n_ptr = tipc_node_find(dest); if (n_ptr) { tipc_node_lock(n_ptr); l_ptr = n_ptr->active_links[selector & 1]; if (l_ptr) res = tipc_link_send_buf(l_ptr, buf); else kfree_skb(buf); tipc_node_unlock(n_ptr); } else { kfree_skb(buf); } read_unlock_bh(&tipc_net_lock); return res; } /* * tipc_link_send_sync - synchronize broadcast link endpoints. * * Give a newly added peer node the sequence number where it should * start receiving and acking broadcast packets. * * Called with node locked */ static void tipc_link_send_sync(struct tipc_link *l) { struct sk_buff *buf; struct tipc_msg *msg; buf = tipc_buf_acquire(INT_H_SIZE); if (!buf) return; msg = buf_msg(buf); tipc_msg_init(msg, BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE, l->addr); msg_set_last_bcast(msg, l->owner->bclink.acked); link_add_chain_to_outqueue(l, buf, 0); tipc_link_push_queue(l); } /* * tipc_link_recv_sync - synchronize broadcast link endpoints. * Receive the sequence number where we should start receiving and * acking broadcast packets from a newly added peer node, and open * up for reception of such packets. * * Called with node locked */ static void tipc_link_recv_sync(struct tipc_node *n, struct sk_buff *buf) { struct tipc_msg *msg = buf_msg(buf); n->bclink.last_sent = n->bclink.last_in = msg_last_bcast(msg); n->bclink.recv_permitted = true; kfree_skb(buf); } /* * tipc_link_send_names - send name table entries to new neighbor * * Send routine for bulk delivery of name table messages when contact * with a new neighbor occurs. No link congestion checking is performed * because name table messages *must* be delivered. The messages must be * small enough not to require fragmentation. * Called without any locks held. */ void tipc_link_send_names(struct list_head *message_list, u32 dest) { struct tipc_node *n_ptr; struct tipc_link *l_ptr; struct sk_buff *buf; struct sk_buff *temp_buf; if (list_empty(message_list)) return; read_lock_bh(&tipc_net_lock); n_ptr = tipc_node_find(dest); if (n_ptr) { tipc_node_lock(n_ptr); l_ptr = n_ptr->active_links[0]; if (l_ptr) { /* convert circular list to linear list */ ((struct sk_buff *)message_list->prev)->next = NULL; link_add_chain_to_outqueue(l_ptr, (struct sk_buff *)message_list->next, 0); tipc_link_push_queue(l_ptr); INIT_LIST_HEAD(message_list); } tipc_node_unlock(n_ptr); } read_unlock_bh(&tipc_net_lock); /* discard the messages if they couldn't be sent */ list_for_each_safe(buf, temp_buf, ((struct sk_buff *)message_list)) { list_del((struct list_head *)buf); kfree_skb(buf); } } /* * link_send_buf_fast: Entry for data messages where the * destination link is known and the header is complete, * inclusive total message length. Very time critical. * Link is locked. Returns user data length. */ static int link_send_buf_fast(struct tipc_link *l_ptr, struct sk_buff *buf, u32 *used_max_pkt) { struct tipc_msg *msg = buf_msg(buf); int res = msg_data_sz(msg); if (likely(!link_congested(l_ptr))) { if (likely(msg_size(msg) <= l_ptr->max_pkt)) { link_add_to_outqueue(l_ptr, buf, msg); tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr); l_ptr->unacked_window = 0; return res; } else *used_max_pkt = l_ptr->max_pkt; } return tipc_link_send_buf(l_ptr, buf); /* All other cases */ } /* * tipc_link_send_sections_fast: Entry for messages where the * destination processor is known and the header is complete, * except for total message length. * Returns user data length or errno. */ int tipc_link_send_sections_fast(struct tipc_port *sender, struct iovec const *msg_sect, unsigned int len, u32 destaddr) { struct tipc_msg *hdr = &sender->phdr; struct tipc_link *l_ptr; struct sk_buff *buf; struct tipc_node *node; int res; u32 selector = msg_origport(hdr) & 1; again: /* * Try building message using port's max_pkt hint. * (Must not hold any locks while building message.) */ res = tipc_msg_build(hdr, msg_sect, len, sender->max_pkt, &buf); /* Exit if build request was invalid */ if (unlikely(res < 0)) return res; read_lock_bh(&tipc_net_lock); node = tipc_node_find(destaddr); if (likely(node)) { tipc_node_lock(node); l_ptr = node->active_links[selector]; if (likely(l_ptr)) { if (likely(buf)) { res = link_send_buf_fast(l_ptr, buf, &sender->max_pkt); exit: tipc_node_unlock(node); read_unlock_bh(&tipc_net_lock); return res; } /* Exit if link (or bearer) is congested */ if (link_congested(l_ptr)) { res = link_schedule_port(l_ptr, sender->ref, res); goto exit; } /* * Message size exceeds max_pkt hint; update hint, * then re-try fast path or fragment the message */ sender->max_pkt = l_ptr->max_pkt; tipc_node_unlock(node); read_unlock_bh(&tipc_net_lock); if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt) goto again; return link_send_sections_long(sender, msg_sect, len, destaddr); } tipc_node_unlock(node); } read_unlock_bh(&tipc_net_lock); /* Couldn't find a link to the destination node */ if (buf) return tipc_reject_msg(buf, TIPC_ERR_NO_NODE); if (res >= 0) return tipc_port_reject_sections(sender, hdr, msg_sect, len, TIPC_ERR_NO_NODE); return res; } /* * link_send_sections_long(): Entry for long messages where the * destination node is known and the header is complete, * inclusive total message length. * Link and bearer congestion status have been checked to be ok, * and are ignored if they change. * * Note that fragments do not use the full link MTU so that they won't have * to undergo refragmentation if link changeover causes them to be sent * over another link with an additional tunnel header added as prefix. * (Refragmentation will still occur if the other link has a smaller MTU.) * * Returns user data length or errno. */ static int link_send_sections_long(struct tipc_port *sender, struct iovec const *msg_sect, unsigned int len, u32 destaddr) { struct tipc_link *l_ptr; struct tipc_node *node; struct tipc_msg *hdr = &sender->phdr; u32 dsz = len; u32 max_pkt, fragm_sz, rest; struct tipc_msg fragm_hdr; struct sk_buff *buf, *buf_chain, *prev; u32 fragm_crs, fragm_rest, hsz, sect_rest; const unchar __user *sect_crs; int curr_sect; u32 fragm_no; int res = 0; again: fragm_no = 1; max_pkt = sender->max_pkt - INT_H_SIZE; /* leave room for tunnel header in case of link changeover */ fragm_sz = max_pkt - INT_H_SIZE; /* leave room for fragmentation header in each fragment */ rest = dsz; fragm_crs = 0; fragm_rest = 0; sect_rest = 0; sect_crs = NULL; curr_sect = -1; /* Prepare reusable fragment header */ tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT, INT_H_SIZE, msg_destnode(hdr)); msg_set_size(&fragm_hdr, max_pkt); msg_set_fragm_no(&fragm_hdr, 1); /* Prepare header of first fragment */ buf_chain = buf = tipc_buf_acquire(max_pkt); if (!buf) return -ENOMEM; buf->next = NULL; skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE); hsz = msg_hdr_sz(hdr); skb_copy_to_linear_data_offset(buf, INT_H_SIZE, hdr, hsz); /* Chop up message */ fragm_crs = INT_H_SIZE + hsz; fragm_rest = fragm_sz - hsz; do { /* For all sections */ u32 sz; if (!sect_rest) { sect_rest = msg_sect[++curr_sect].iov_len; sect_crs = msg_sect[curr_sect].iov_base; } if (sect_rest < fragm_rest) sz = sect_rest; else sz = fragm_rest; if (copy_from_user(buf->data + fragm_crs, sect_crs, sz)) { res = -EFAULT; error: kfree_skb_list(buf_chain); return res; } sect_crs += sz; sect_rest -= sz; fragm_crs += sz; fragm_rest -= sz; rest -= sz; if (!fragm_rest && rest) { /* Initiate new fragment: */ if (rest <= fragm_sz) { fragm_sz = rest; msg_set_type(&fragm_hdr, LAST_FRAGMENT); } else { msg_set_type(&fragm_hdr, FRAGMENT); } msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE); msg_set_fragm_no(&fragm_hdr, ++fragm_no); prev = buf; buf = tipc_buf_acquire(fragm_sz + INT_H_SIZE); if (!buf) { res = -ENOMEM; goto error; } buf->next = NULL; prev->next = buf; skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE); fragm_crs = INT_H_SIZE; fragm_rest = fragm_sz; } } while (rest > 0); /* * Now we have a buffer chain. Select a link and check * that packet size is still OK */ node = tipc_node_find(destaddr); if (likely(node)) { tipc_node_lock(node); l_ptr = node->active_links[sender->ref & 1]; if (!l_ptr) { tipc_node_unlock(node); goto reject; } if (l_ptr->max_pkt < max_pkt) { sender->max_pkt = l_ptr->max_pkt; tipc_node_unlock(node); kfree_skb_list(buf_chain); goto again; } } else { reject: kfree_skb_list(buf_chain); return tipc_port_reject_sections(sender, hdr, msg_sect, len, TIPC_ERR_NO_NODE); } /* Append chain of fragments to send queue & send them */ l_ptr->long_msg_seq_no++; link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no); l_ptr->stats.sent_fragments += fragm_no; l_ptr->stats.sent_fragmented++; tipc_link_push_queue(l_ptr); tipc_node_unlock(node); return dsz; } /* * tipc_link_push_packet: Push one unsent packet to the media */ static u32 tipc_link_push_packet(struct tipc_link *l_ptr) { struct sk_buff *buf = l_ptr->first_out; u32 r_q_size = l_ptr->retransm_queue_size; u32 r_q_head = l_ptr->retransm_queue_head; /* Step to position where retransmission failed, if any, */ /* consider that buffers may have been released in meantime */ if (r_q_size && buf) { u32 last = lesser(mod(r_q_head + r_q_size), link_last_sent(l_ptr)); u32 first = buf_seqno(buf); while (buf && less(first, r_q_head)) { first = mod(first + 1); buf = buf->next; } l_ptr->retransm_queue_head = r_q_head = first; l_ptr->retransm_queue_size = r_q_size = mod(last - first); } /* Continue retransmission now, if there is anything: */ if (r_q_size && buf) { msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1)); msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in); tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr); l_ptr->retransm_queue_head = mod(++r_q_head); l_ptr->retransm_queue_size = --r_q_size; l_ptr->stats.retransmitted++; return 0; } /* Send deferred protocol message, if any: */ buf = l_ptr->proto_msg_queue; if (buf) { msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1)); msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in); tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr); l_ptr->unacked_window = 0; kfree_skb(buf); l_ptr->proto_msg_queue = NULL; return 0; } /* Send one deferred data message, if send window not full: */ buf = l_ptr->next_out; if (buf) { struct tipc_msg *msg = buf_msg(buf); u32 next = msg_seqno(msg); u32 first = buf_seqno(l_ptr->first_out); if (mod(next - first) < l_ptr->queue_limit[0]) { msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr); if (msg_user(msg) == MSG_BUNDLER) msg_set_type(msg, CLOSED_MSG); l_ptr->next_out = buf->next; return 0; } } return 1; } /* * push_queue(): push out the unsent messages of a link where * congestion has abated. Node is locked */ void tipc_link_push_queue(struct tipc_link *l_ptr) { u32 res; do { res = tipc_link_push_packet(l_ptr); } while (!res); } static void link_reset_all(unsigned long addr) { struct tipc_node *n_ptr; char addr_string[16]; u32 i; read_lock_bh(&tipc_net_lock); n_ptr = tipc_node_find((u32)addr); if (!n_ptr) { read_unlock_bh(&tipc_net_lock); return; /* node no longer exists */ } tipc_node_lock(n_ptr); pr_warn("Resetting all links to %s\n", tipc_addr_string_fill(addr_string, n_ptr->addr)); for (i = 0; i < MAX_BEARERS; i++) { if (n_ptr->links[i]) { link_print(n_ptr->links[i], "Resetting link\n"); tipc_link_reset(n_ptr->links[i]); } } tipc_node_unlock(n_ptr); read_unlock_bh(&tipc_net_lock); } static void link_retransmit_failure(struct tipc_link *l_ptr, struct sk_buff *buf) { struct tipc_msg *msg = buf_msg(buf); pr_warn("Retransmission failure on link <%s>\n", l_ptr->name); if (l_ptr->addr) { /* Handle failure on standard link */ link_print(l_ptr, "Resetting link\n"); tipc_link_reset(l_ptr); } else { /* Handle failure on broadcast link */ struct tipc_node *n_ptr; char addr_string[16]; pr_info("Msg seq number: %u, ", msg_seqno(msg)); pr_cont("Outstanding acks: %lu\n", (unsigned long) TIPC_SKB_CB(buf)->handle); n_ptr = tipc_bclink_retransmit_to(); tipc_node_lock(n_ptr); tipc_addr_string_fill(addr_string, n_ptr->addr); pr_info("Broadcast link info for %s\n", addr_string); pr_info("Reception permitted: %d, Acked: %u\n", n_ptr->bclink.recv_permitted, n_ptr->bclink.acked); pr_info("Last in: %u, Oos state: %u, Last sent: %u\n", n_ptr->bclink.last_in, n_ptr->bclink.oos_state, n_ptr->bclink.last_sent); tipc_k_signal((Handler)link_reset_all, (unsigned long)n_ptr->addr); tipc_node_unlock(n_ptr); l_ptr->stale_count = 0; } } void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *buf, u32 retransmits) { struct tipc_msg *msg; if (!buf) return; msg = buf_msg(buf); /* Detect repeated retransmit failures */ if (l_ptr->last_retransmitted == msg_seqno(msg)) { if (++l_ptr->stale_count > 100) { link_retransmit_failure(l_ptr, buf); return; } } else { l_ptr->last_retransmitted = msg_seqno(msg); l_ptr->stale_count = 1; } while (retransmits && (buf != l_ptr->next_out) && buf) { msg = buf_msg(buf); msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr); buf = buf->next; retransmits--; l_ptr->stats.retransmitted++; } l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0; } /** * link_insert_deferred_queue - insert deferred messages back into receive chain */ static struct sk_buff *link_insert_deferred_queue(struct tipc_link *l_ptr, struct sk_buff *buf) { u32 seq_no; if (l_ptr->oldest_deferred_in == NULL) return buf; seq_no = buf_seqno(l_ptr->oldest_deferred_in); if (seq_no == mod(l_ptr->next_in_no)) { l_ptr->newest_deferred_in->next = buf; buf = l_ptr->oldest_deferred_in; l_ptr->oldest_deferred_in = NULL; l_ptr->deferred_inqueue_sz = 0; } return buf; } /** * link_recv_buf_validate - validate basic format of received message * * This routine ensures a TIPC message has an acceptable header, and at least * as much data as the header indicates it should. The routine also ensures * that the entire message header is stored in the main fragment of the message * buffer, to simplify future access to message header fields. * * Note: Having extra info present in the message header or data areas is OK. * TIPC will ignore the excess, under the assumption that it is optional info * introduced by a later release of the protocol. */ static int link_recv_buf_validate(struct sk_buff *buf) { static u32 min_data_hdr_size[8] = { SHORT_H_SIZE, MCAST_H_SIZE, NAMED_H_SIZE, BASIC_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE }; struct tipc_msg *msg; u32 tipc_hdr[2]; u32 size; u32 hdr_size; u32 min_hdr_size; if (unlikely(buf->len < MIN_H_SIZE)) return 0; msg = skb_header_pointer(buf, 0, sizeof(tipc_hdr), tipc_hdr); if (msg == NULL) return 0; if (unlikely(msg_version(msg) != TIPC_VERSION)) return 0; size = msg_size(msg); hdr_size = msg_hdr_sz(msg); min_hdr_size = msg_isdata(msg) ? min_data_hdr_size[msg_type(msg)] : INT_H_SIZE; if (unlikely((hdr_size < min_hdr_size) || (size < hdr_size) || (buf->len < size) || (size - hdr_size > TIPC_MAX_USER_MSG_SIZE))) return 0; return pskb_may_pull(buf, hdr_size); } /** * tipc_rcv - process TIPC packets/messages arriving from off-node * @head: pointer to message buffer chain * @tb_ptr: pointer to bearer message arrived on * * Invoked with no locks held. Bearer pointer must point to a valid bearer * structure (i.e. cannot be NULL), but bearer can be inactive. */ void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr) { read_lock_bh(&tipc_net_lock); while (head) { struct tipc_node *n_ptr; struct tipc_link *l_ptr; struct sk_buff *crs; struct sk_buff *buf = head; struct tipc_msg *msg; u32 seq_no; u32 ackd; u32 released = 0; head = head->next; buf->next = NULL; /* Ensure bearer is still enabled */ if (unlikely(!b_ptr->active)) goto discard; /* Ensure message is well-formed */ if (unlikely(!link_recv_buf_validate(buf))) goto discard; /* Ensure message data is a single contiguous unit */ if (unlikely(skb_linearize(buf))) goto discard; /* Handle arrival of a non-unicast link message */ msg = buf_msg(buf); if (unlikely(msg_non_seq(msg))) { if (msg_user(msg) == LINK_CONFIG) tipc_disc_recv_msg(buf, b_ptr); else tipc_bclink_recv_pkt(buf); continue; } /* Discard unicast link messages destined for another node */ if (unlikely(!msg_short(msg) && (msg_destnode(msg) != tipc_own_addr))) goto discard; /* Locate neighboring node that sent message */ n_ptr = tipc_node_find(msg_prevnode(msg)); if (unlikely(!n_ptr)) goto discard; tipc_node_lock(n_ptr); /* Locate unicast link endpoint that should handle message */ l_ptr = n_ptr->links[b_ptr->identity]; if (unlikely(!l_ptr)) goto unlock_discard; /* Verify that communication with node is currently allowed */ if ((n_ptr->block_setup & WAIT_PEER_DOWN) && msg_user(msg) == LINK_PROTOCOL && (msg_type(msg) == RESET_MSG || msg_type(msg) == ACTIVATE_MSG) && !msg_redundant_link(msg)) n_ptr->block_setup &= ~WAIT_PEER_DOWN; if (n_ptr->block_setup) goto unlock_discard; /* Validate message sequence number info */ seq_no = msg_seqno(msg); ackd = msg_ack(msg); /* Release acked messages */ if (n_ptr->bclink.recv_permitted) tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg)); crs = l_ptr->first_out; while ((crs != l_ptr->next_out) && less_eq(buf_seqno(crs), ackd)) { struct sk_buff *next = crs->next; kfree_skb(crs); crs = next; released++; } if (released) { l_ptr->first_out = crs; l_ptr->out_queue_size -= released; } /* Try sending any messages link endpoint has pending */ if (unlikely(l_ptr->next_out)) tipc_link_push_queue(l_ptr); if (unlikely(!list_empty(&l_ptr->waiting_ports))) tipc_link_wakeup_ports(l_ptr, 0); if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) { l_ptr->stats.sent_acks++; tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0); } /* Process the incoming packet */ if (unlikely(!link_working_working(l_ptr))) { if (msg_user(msg) == LINK_PROTOCOL) { link_recv_proto_msg(l_ptr, buf); head = link_insert_deferred_queue(l_ptr, head); tipc_node_unlock(n_ptr); continue; } /* Traffic message. Conditionally activate link */ link_state_event(l_ptr, TRAFFIC_MSG_EVT); if (link_working_working(l_ptr)) { /* Re-insert buffer in front of queue */ buf->next = head; head = buf; tipc_node_unlock(n_ptr); continue; } goto unlock_discard; } /* Link is now in state WORKING_WORKING */ if (unlikely(seq_no != mod(l_ptr->next_in_no))) { link_handle_out_of_seq_msg(l_ptr, buf); head = link_insert_deferred_queue(l_ptr, head); tipc_node_unlock(n_ptr); continue; } l_ptr->next_in_no++; if (unlikely(l_ptr->oldest_deferred_in)) head = link_insert_deferred_queue(l_ptr, head); /* Deliver packet/message to correct user: */ if (unlikely(msg_user(msg) == CHANGEOVER_PROTOCOL)) { if (!tipc_link_tunnel_rcv(n_ptr, &buf)) { tipc_node_unlock(n_ptr); continue; } msg = buf_msg(buf); } else if (msg_user(msg) == MSG_FRAGMENTER) { int rc; l_ptr->stats.recv_fragments++; rc = tipc_link_frag_rcv(&l_ptr->reasm_head, &l_ptr->reasm_tail, &buf); if (rc == LINK_REASM_COMPLETE) { l_ptr->stats.recv_fragmented++; msg = buf_msg(buf); } else { if (rc == LINK_REASM_ERROR) tipc_link_reset(l_ptr); tipc_node_unlock(n_ptr); continue; } } switch (msg_user(msg)) { case TIPC_LOW_IMPORTANCE: case TIPC_MEDIUM_IMPORTANCE: case TIPC_HIGH_IMPORTANCE: case TIPC_CRITICAL_IMPORTANCE: tipc_node_unlock(n_ptr); tipc_port_recv_msg(buf); continue; case MSG_BUNDLER: l_ptr->stats.recv_bundles++; l_ptr->stats.recv_bundled += msg_msgcnt(msg); tipc_node_unlock(n_ptr); tipc_link_recv_bundle(buf); continue; case NAME_DISTRIBUTOR: n_ptr->bclink.recv_permitted = true; tipc_node_unlock(n_ptr); tipc_named_recv(buf); continue; case CONN_MANAGER: tipc_node_unlock(n_ptr); tipc_port_recv_proto_msg(buf); continue; case BCAST_PROTOCOL: tipc_link_recv_sync(n_ptr, buf); break; default: kfree_skb(buf); break; } tipc_node_unlock(n_ptr); continue; unlock_discard: tipc_node_unlock(n_ptr); discard: kfree_skb(buf); } read_unlock_bh(&tipc_net_lock); } /** * tipc_link_defer_pkt - Add out-of-sequence message to deferred reception queue * * Returns increase in queue length (i.e. 0 or 1) */ u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail, struct sk_buff *buf) { struct sk_buff *queue_buf; struct sk_buff **prev; u32 seq_no = buf_seqno(buf); buf->next = NULL; /* Empty queue ? */ if (*head == NULL) { *head = *tail = buf; return 1; } /* Last ? */ if (less(buf_seqno(*tail), seq_no)) { (*tail)->next = buf; *tail = buf; return 1; } /* Locate insertion point in queue, then insert; discard if duplicate */ prev = head; queue_buf = *head; for (;;) { u32 curr_seqno = buf_seqno(queue_buf); if (seq_no == curr_seqno) { kfree_skb(buf); return 0; } if (less(seq_no, curr_seqno)) break; prev = &queue_buf->next; queue_buf = queue_buf->next; } buf->next = queue_buf; *prev = buf; return 1; } /* * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet */ static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr, struct sk_buff *buf) { u32 seq_no = buf_seqno(buf); if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) { link_recv_proto_msg(l_ptr, buf); return; } /* Record OOS packet arrival (force mismatch on next timeout) */ l_ptr->checkpoint--; /* * Discard packet if a duplicate; otherwise add it to deferred queue * and notify peer of gap as per protocol specification */ if (less(seq_no, mod(l_ptr->next_in_no))) { l_ptr->stats.duplicates++; kfree_skb(buf); return; } if (tipc_link_defer_pkt(&l_ptr->oldest_deferred_in, &l_ptr->newest_deferred_in, buf)) { l_ptr->deferred_inqueue_sz++; l_ptr->stats.deferred_recv++; if ((l_ptr->deferred_inqueue_sz % 16) == 1) tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0); } else l_ptr->stats.duplicates++; } /* * Send protocol message to the other endpoint. */ void tipc_link_send_proto_msg(struct tipc_link *l_ptr, u32 msg_typ, int probe_msg, u32 gap, u32 tolerance, u32 priority, u32 ack_mtu) { struct sk_buff *buf = NULL; struct tipc_msg *msg = l_ptr->pmsg; u32 msg_size = sizeof(l_ptr->proto_msg); int r_flag; /* Discard any previous message that was deferred due to congestion */ if (l_ptr->proto_msg_queue) { kfree_skb(l_ptr->proto_msg_queue); l_ptr->proto_msg_queue = NULL; } /* Don't send protocol message during link changeover */ if (l_ptr->exp_msg_count) return; /* Abort non-RESET send if communication with node is prohibited */ if ((l_ptr->owner->block_setup) && (msg_typ != RESET_MSG)) return; /* Create protocol message with "out-of-sequence" sequence number */ msg_set_type(msg, msg_typ); msg_set_net_plane(msg, l_ptr->b_ptr->net_plane); msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); msg_set_last_bcast(msg, tipc_bclink_get_last_sent()); if (msg_typ == STATE_MSG) { u32 next_sent = mod(l_ptr->next_out_no); if (!tipc_link_is_up(l_ptr)) return; if (l_ptr->next_out) next_sent = buf_seqno(l_ptr->next_out); msg_set_next_sent(msg, next_sent); if (l_ptr->oldest_deferred_in) { u32 rec = buf_seqno(l_ptr->oldest_deferred_in); gap = mod(rec - mod(l_ptr->next_in_no)); } msg_set_seq_gap(msg, gap); if (gap) l_ptr->stats.sent_nacks++; msg_set_link_tolerance(msg, tolerance); msg_set_linkprio(msg, priority); msg_set_max_pkt(msg, ack_mtu); msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); msg_set_probe(msg, probe_msg != 0); if (probe_msg) { u32 mtu = l_ptr->max_pkt; if ((mtu < l_ptr->max_pkt_target) && link_working_working(l_ptr) && l_ptr->fsm_msg_cnt) { msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3; if (l_ptr->max_pkt_probes == 10) { l_ptr->max_pkt_target = (msg_size - 4); l_ptr->max_pkt_probes = 0; msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3; } l_ptr->max_pkt_probes++; } l_ptr->stats.sent_probes++; } l_ptr->stats.sent_states++; } else { /* RESET_MSG or ACTIVATE_MSG */ msg_set_ack(msg, mod(l_ptr->reset_checkpoint - 1)); msg_set_seq_gap(msg, 0); msg_set_next_sent(msg, 1); msg_set_probe(msg, 0); msg_set_link_tolerance(msg, l_ptr->tolerance); msg_set_linkprio(msg, l_ptr->priority); msg_set_max_pkt(msg, l_ptr->max_pkt_target); } r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr)); msg_set_redundant_link(msg, r_flag); msg_set_linkprio(msg, l_ptr->priority); msg_set_size(msg, msg_size); msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2))); buf = tipc_buf_acquire(msg_size); if (!buf) return; skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg)); buf->priority = TC_PRIO_CONTROL; tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr); l_ptr->unacked_window = 0; kfree_skb(buf); } /* * Receive protocol message : * Note that network plane id propagates through the network, and may * change at any time. The node with lowest address rules */ static void link_recv_proto_msg(struct tipc_link *l_ptr, struct sk_buff *buf) { u32 rec_gap = 0; u32 max_pkt_info; u32 max_pkt_ack; u32 msg_tol; struct tipc_msg *msg = buf_msg(buf); /* Discard protocol message during link changeover */ if (l_ptr->exp_msg_count) goto exit; /* record unnumbered packet arrival (force mismatch on next timeout) */ l_ptr->checkpoint--; if (l_ptr->b_ptr->net_plane != msg_net_plane(msg)) if (tipc_own_addr > msg_prevnode(msg)) l_ptr->b_ptr->net_plane = msg_net_plane(msg); switch (msg_type(msg)) { case RESET_MSG: if (!link_working_unknown(l_ptr) && (l_ptr->peer_session != INVALID_SESSION)) { if (less_eq(msg_session(msg), l_ptr->peer_session)) break; /* duplicate or old reset: ignore */ } if (!msg_redundant_link(msg) && (link_working_working(l_ptr) || link_working_unknown(l_ptr))) { /* * peer has lost contact -- don't allow peer's links * to reactivate before we recognize loss & clean up */ l_ptr->owner->block_setup = WAIT_NODE_DOWN; } link_state_event(l_ptr, RESET_MSG); /* fall thru' */ case ACTIVATE_MSG: /* Update link settings according other endpoint's values */ strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg)); msg_tol = msg_link_tolerance(msg); if (msg_tol > l_ptr->tolerance) link_set_supervision_props(l_ptr, msg_tol); if (msg_linkprio(msg) > l_ptr->priority) l_ptr->priority = msg_linkprio(msg); max_pkt_info = msg_max_pkt(msg); if (max_pkt_info) { if (max_pkt_info < l_ptr->max_pkt_target) l_ptr->max_pkt_target = max_pkt_info; if (l_ptr->max_pkt > l_ptr->max_pkt_target) l_ptr->max_pkt = l_ptr->max_pkt_target; } else { l_ptr->max_pkt = l_ptr->max_pkt_target; } /* Synchronize broadcast link info, if not done previously */ if (!tipc_node_is_up(l_ptr->owner)) { l_ptr->owner->bclink.last_sent = l_ptr->owner->bclink.last_in = msg_last_bcast(msg); l_ptr->owner->bclink.oos_state = 0; } l_ptr->peer_session = msg_session(msg); l_ptr->peer_bearer_id = msg_bearer_id(msg); if (msg_type(msg) == ACTIVATE_MSG) link_state_event(l_ptr, ACTIVATE_MSG); break; case STATE_MSG: msg_tol = msg_link_tolerance(msg); if (msg_tol) link_set_supervision_props(l_ptr, msg_tol); if (msg_linkprio(msg) && (msg_linkprio(msg) != l_ptr->priority)) { pr_warn("%s<%s>, priority change %u->%u\n", link_rst_msg, l_ptr->name, l_ptr->priority, msg_linkprio(msg)); l_ptr->priority = msg_linkprio(msg); tipc_link_reset(l_ptr); /* Enforce change to take effect */ break; } link_state_event(l_ptr, TRAFFIC_MSG_EVT); l_ptr->stats.recv_states++; if (link_reset_unknown(l_ptr)) break; if (less_eq(mod(l_ptr->next_in_no), msg_next_sent(msg))) { rec_gap = mod(msg_next_sent(msg) - mod(l_ptr->next_in_no)); } max_pkt_ack = msg_max_pkt(msg); if (max_pkt_ack > l_ptr->max_pkt) { l_ptr->max_pkt = max_pkt_ack; l_ptr->max_pkt_probes = 0; } max_pkt_ack = 0; if (msg_probe(msg)) { l_ptr->stats.recv_probes++; if (msg_size(msg) > sizeof(l_ptr->proto_msg)) max_pkt_ack = msg_size(msg); } /* Protocol message before retransmits, reduce loss risk */ if (l_ptr->owner->bclink.recv_permitted) tipc_bclink_update_link_state(l_ptr->owner, msg_last_bcast(msg)); if (rec_gap || (msg_probe(msg))) { tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, rec_gap, 0, 0, max_pkt_ack); } if (msg_seq_gap(msg)) { l_ptr->stats.recv_nacks++; tipc_link_retransmit(l_ptr, l_ptr->first_out, msg_seq_gap(msg)); } break; } exit: kfree_skb(buf); } /* tipc_link_tunnel_xmit(): Tunnel one packet via a link belonging to * a different bearer. Owner node is locked. */ static void tipc_link_tunnel_xmit(struct tipc_link *l_ptr, struct tipc_msg *tunnel_hdr, struct tipc_msg *msg, u32 selector) { struct tipc_link *tunnel; struct sk_buff *buf; u32 length = msg_size(msg); tunnel = l_ptr->owner->active_links[selector & 1]; if (!tipc_link_is_up(tunnel)) { pr_warn("%stunnel link no longer available\n", link_co_err); return; } msg_set_size(tunnel_hdr, length + INT_H_SIZE); buf = tipc_buf_acquire(length + INT_H_SIZE); if (!buf) { pr_warn("%sunable to send tunnel msg\n", link_co_err); return; } skb_copy_to_linear_data(buf, tunnel_hdr, INT_H_SIZE); skb_copy_to_linear_data_offset(buf, INT_H_SIZE, msg, length); tipc_link_send_buf(tunnel, buf); } /* tipc_link_failover_send_queue(): A link has gone down, but a second * link is still active. We can do failover. Tunnel the failing link's * whole send queue via the remaining link. This way, we don't lose * any packets, and sequence order is preserved for subsequent traffic * sent over the remaining link. Owner node is locked. */ void tipc_link_failover_send_queue(struct tipc_link *l_ptr) { u32 msgcount = l_ptr->out_queue_size; struct sk_buff *crs = l_ptr->first_out; struct tipc_link *tunnel = l_ptr->owner->active_links[0]; struct tipc_msg tunnel_hdr; int split_bundles; if (!tunnel) return; tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL, ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr); msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id); msg_set_msgcnt(&tunnel_hdr, msgcount); if (!l_ptr->first_out) { struct sk_buff *buf; buf = tipc_buf_acquire(INT_H_SIZE); if (buf) { skb_copy_to_linear_data(buf, &tunnel_hdr, INT_H_SIZE); msg_set_size(&tunnel_hdr, INT_H_SIZE); tipc_link_send_buf(tunnel, buf); } else { pr_warn("%sunable to send changeover msg\n", link_co_err); } return; } split_bundles = (l_ptr->owner->active_links[0] != l_ptr->owner->active_links[1]); while (crs) { struct tipc_msg *msg = buf_msg(crs); if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) { struct tipc_msg *m = msg_get_wrapped(msg); unchar *pos = (unchar *)m; msgcount = msg_msgcnt(msg); while (msgcount--) { msg_set_seqno(m, msg_seqno(msg)); tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, m, msg_link_selector(m)); pos += align(msg_size(m)); m = (struct tipc_msg *)pos; } } else { tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, msg, msg_link_selector(msg)); } crs = crs->next; } } /* tipc_link_dup_send_queue(): A second link has become active. Tunnel a * duplicate of the first link's send queue via the new link. This way, we * are guaranteed that currently queued packets from a socket are delivered * before future traffic from the same socket, even if this is using the * new link. The last arriving copy of each duplicate packet is dropped at * the receiving end by the regular protocol check, so packet cardinality * and sequence order is preserved per sender/receiver socket pair. * Owner node is locked. */ void tipc_link_dup_send_queue(struct tipc_link *l_ptr, struct tipc_link *tunnel) { struct sk_buff *iter; struct tipc_msg tunnel_hdr; tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL, DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr); msg_set_msgcnt(&tunnel_hdr, l_ptr->out_queue_size); msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id); iter = l_ptr->first_out; while (iter) { struct sk_buff *outbuf; struct tipc_msg *msg = buf_msg(iter); u32 length = msg_size(msg); if (msg_user(msg) == MSG_BUNDLER) msg_set_type(msg, CLOSED_MSG); msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); /* Update */ msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in); msg_set_size(&tunnel_hdr, length + INT_H_SIZE); outbuf = tipc_buf_acquire(length + INT_H_SIZE); if (outbuf == NULL) { pr_warn("%sunable to send duplicate msg\n", link_co_err); return; } skb_copy_to_linear_data(outbuf, &tunnel_hdr, INT_H_SIZE); skb_copy_to_linear_data_offset(outbuf, INT_H_SIZE, iter->data, length); tipc_link_send_buf(tunnel, outbuf); if (!tipc_link_is_up(l_ptr)) return; iter = iter->next; } } /** * buf_extract - extracts embedded TIPC message from another message * @skb: encapsulating message buffer * @from_pos: offset to extract from * * Returns a new message buffer containing an embedded message. The * encapsulating message itself is left unchanged. */ static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos) { struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos); u32 size = msg_size(msg); struct sk_buff *eb; eb = tipc_buf_acquire(size); if (eb) skb_copy_to_linear_data(eb, msg, size); return eb; } /* tipc_link_dup_rcv(): Receive a tunnelled DUPLICATE_MSG packet. * Owner node is locked. */ static void tipc_link_dup_rcv(struct tipc_link *l_ptr, struct sk_buff *t_buf) { struct sk_buff *buf; if (!tipc_link_is_up(l_ptr)) return; buf = buf_extract(t_buf, INT_H_SIZE); if (buf == NULL) { pr_warn("%sfailed to extract inner dup pkt\n", link_co_err); return; } /* Add buffer to deferred queue, if applicable: */ link_handle_out_of_seq_msg(l_ptr, buf); } /* tipc_link_failover_rcv(): Receive a tunnelled ORIGINAL_MSG packet * Owner node is locked. */ static struct sk_buff *tipc_link_failover_rcv(struct tipc_link *l_ptr, struct sk_buff *t_buf) { struct tipc_msg *t_msg = buf_msg(t_buf); struct sk_buff *buf = NULL; struct tipc_msg *msg; if (tipc_link_is_up(l_ptr)) tipc_link_reset(l_ptr); /* First failover packet? */ if (l_ptr->exp_msg_count == START_CHANGEOVER) l_ptr->exp_msg_count = msg_msgcnt(t_msg); /* Should there be an inner packet? */ if (l_ptr->exp_msg_count) { l_ptr->exp_msg_count--; buf = buf_extract(t_buf, INT_H_SIZE); if (buf == NULL) { pr_warn("%sno inner failover pkt\n", link_co_err); goto exit; } msg = buf_msg(buf); if (less(msg_seqno(msg), l_ptr->reset_checkpoint)) { kfree_skb(buf); buf = NULL; goto exit; } if (msg_user(msg) == MSG_FRAGMENTER) { l_ptr->stats.recv_fragments++; tipc_link_frag_rcv(&l_ptr->reasm_head, &l_ptr->reasm_tail, &buf); } } exit: if ((l_ptr->exp_msg_count == 0) && (l_ptr->flags & LINK_STOPPED)) { tipc_node_detach_link(l_ptr->owner, l_ptr); kfree(l_ptr); } return buf; } /* tipc_link_tunnel_rcv(): Receive a tunnelled packet, sent * via other link as result of a failover (ORIGINAL_MSG) or * a new active link (DUPLICATE_MSG). Failover packets are * returned to the active link for delivery upwards. * Owner node is locked. */ static int tipc_link_tunnel_rcv(struct tipc_node *n_ptr, struct sk_buff **buf) { struct sk_buff *t_buf = *buf; struct tipc_link *l_ptr; struct tipc_msg *t_msg = buf_msg(t_buf); u32 bearer_id = msg_bearer_id(t_msg); *buf = NULL; if (bearer_id >= MAX_BEARERS) goto exit; l_ptr = n_ptr->links[bearer_id]; if (!l_ptr) goto exit; if (msg_type(t_msg) == DUPLICATE_MSG) tipc_link_dup_rcv(l_ptr, t_buf); else if (msg_type(t_msg) == ORIGINAL_MSG) *buf = tipc_link_failover_rcv(l_ptr, t_buf); else pr_warn("%sunknown tunnel pkt received\n", link_co_err); exit: kfree_skb(t_buf); return *buf != NULL; } /* * Bundler functionality: */ void tipc_link_recv_bundle(struct sk_buff *buf) { u32 msgcount = msg_msgcnt(buf_msg(buf)); u32 pos = INT_H_SIZE; struct sk_buff *obuf; while (msgcount--) { obuf = buf_extract(buf, pos); if (obuf == NULL) { pr_warn("Link unable to unbundle message(s)\n"); break; } pos += align(msg_size(buf_msg(obuf))); tipc_net_route_msg(obuf); } kfree_skb(buf); } /* * Fragmentation/defragmentation: */ /* * link_send_long_buf: Entry for buffers needing fragmentation. * The buffer is complete, inclusive total message length. * Returns user data length. */ static int link_send_long_buf(struct tipc_link *l_ptr, struct sk_buff *buf) { struct sk_buff *buf_chain = NULL; struct sk_buff *buf_chain_tail = (struct sk_buff *)&buf_chain; struct tipc_msg *inmsg = buf_msg(buf); struct tipc_msg fragm_hdr; u32 insize = msg_size(inmsg); u32 dsz = msg_data_sz(inmsg); unchar *crs = buf->data; u32 rest = insize; u32 pack_sz = l_ptr->max_pkt; u32 fragm_sz = pack_sz - INT_H_SIZE; u32 fragm_no = 0; u32 destaddr; if (msg_short(inmsg)) destaddr = l_ptr->addr; else destaddr = msg_destnode(inmsg); /* Prepare reusable fragment header: */ tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT, INT_H_SIZE, destaddr); /* Chop up message: */ while (rest > 0) { struct sk_buff *fragm; if (rest <= fragm_sz) { fragm_sz = rest; msg_set_type(&fragm_hdr, LAST_FRAGMENT); } fragm = tipc_buf_acquire(fragm_sz + INT_H_SIZE); if (fragm == NULL) { kfree_skb(buf); kfree_skb_list(buf_chain); return -ENOMEM; } msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE); fragm_no++; msg_set_fragm_no(&fragm_hdr, fragm_no); skb_copy_to_linear_data(fragm, &fragm_hdr, INT_H_SIZE); skb_copy_to_linear_data_offset(fragm, INT_H_SIZE, crs, fragm_sz); buf_chain_tail->next = fragm; buf_chain_tail = fragm; rest -= fragm_sz; crs += fragm_sz; msg_set_type(&fragm_hdr, FRAGMENT); } kfree_skb(buf); /* Append chain of fragments to send queue & send them */ l_ptr->long_msg_seq_no++; link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no); l_ptr->stats.sent_fragments += fragm_no; l_ptr->stats.sent_fragmented++; tipc_link_push_queue(l_ptr); return dsz; } /* tipc_link_frag_rcv(): Called with node lock on. Returns * the reassembled buffer if message is complete. */ int tipc_link_frag_rcv(struct sk_buff **head, struct sk_buff **tail, struct sk_buff **fbuf) { struct sk_buff *frag = *fbuf; struct tipc_msg *msg = buf_msg(frag); u32 fragid = msg_type(msg); bool headstolen; int delta; skb_pull(frag, msg_hdr_sz(msg)); if (fragid == FIRST_FRAGMENT) { if (*head || skb_unclone(frag, GFP_ATOMIC)) goto out_free; *head = frag; skb_frag_list_init(*head); *fbuf = NULL; return 0; } else if (*head && skb_try_coalesce(*head, frag, &headstolen, &delta)) { kfree_skb_partial(frag, headstolen); } else { if (!*head) goto out_free; if (!skb_has_frag_list(*head)) skb_shinfo(*head)->frag_list = frag; else (*tail)->next = frag; *tail = frag; (*head)->truesize += frag->truesize; } if (fragid == LAST_FRAGMENT) { *fbuf = *head; *tail = *head = NULL; return LINK_REASM_COMPLETE; } *fbuf = NULL; return 0; out_free: pr_warn_ratelimited("Link unable to reassemble fragmented message\n"); kfree_skb(*fbuf); *fbuf = NULL; return LINK_REASM_ERROR; } static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance) { if ((tolerance < TIPC_MIN_LINK_TOL) || (tolerance > TIPC_MAX_LINK_TOL)) return; l_ptr->tolerance = tolerance; l_ptr->continuity_interval = ((tolerance / 4) > 500) ? 500 : tolerance / 4; l_ptr->abort_limit = tolerance / (l_ptr->continuity_interval / 4); } void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window) { /* Data messages from this node, inclusive FIRST_FRAGM */ l_ptr->queue_limit[TIPC_LOW_IMPORTANCE] = window; l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE] = (window / 3) * 4; l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE] = (window / 3) * 5; l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE] = (window / 3) * 6; /* Transiting data messages,inclusive FIRST_FRAGM */ l_ptr->queue_limit[TIPC_LOW_IMPORTANCE + 4] = 300; l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE + 4] = 600; l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE + 4] = 900; l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE + 4] = 1200; l_ptr->queue_limit[CONN_MANAGER] = 1200; l_ptr->queue_limit[CHANGEOVER_PROTOCOL] = 2500; l_ptr->queue_limit[NAME_DISTRIBUTOR] = 3000; /* FRAGMENT and LAST_FRAGMENT packets */ l_ptr->queue_limit[MSG_FRAGMENTER] = 4000; } /* tipc_link_find_owner - locate owner node of link by link's name * @name: pointer to link name string * @bearer_id: pointer to index in 'node->links' array where the link was found. * Caller must hold 'tipc_net_lock' to ensure node and bearer are not deleted; * this also prevents link deletion. * * Returns pointer to node owning the link, or 0 if no matching link is found. */ static struct tipc_node *tipc_link_find_owner(const char *link_name, unsigned int *bearer_id) { struct tipc_link *l_ptr; struct tipc_node *n_ptr; struct tipc_node *tmp_n_ptr; struct tipc_node *found_node = 0; int i; *bearer_id = 0; list_for_each_entry_safe(n_ptr, tmp_n_ptr, &tipc_node_list, list) { tipc_node_lock(n_ptr); for (i = 0; i < MAX_BEARERS; i++) { l_ptr = n_ptr->links[i]; if (l_ptr && !strcmp(l_ptr->name, link_name)) { *bearer_id = i; found_node = n_ptr; break; } } tipc_node_unlock(n_ptr); if (found_node) break; } return found_node; } /** * link_value_is_valid -- validate proposed link tolerance/priority/window * * @cmd: value type (TIPC_CMD_SET_LINK_*) * @new_value: the new value * * Returns 1 if value is within range, 0 if not. */ static int link_value_is_valid(u16 cmd, u32 new_value) { switch (cmd) { case TIPC_CMD_SET_LINK_TOL: return (new_value >= TIPC_MIN_LINK_TOL) && (new_value <= TIPC_MAX_LINK_TOL); case TIPC_CMD_SET_LINK_PRI: return (new_value <= TIPC_MAX_LINK_PRI); case TIPC_CMD_SET_LINK_WINDOW: return (new_value >= TIPC_MIN_LINK_WIN) && (new_value <= TIPC_MAX_LINK_WIN); } return 0; } /** * link_cmd_set_value - change priority/tolerance/window for link/bearer/media * @name: ptr to link, bearer, or media name * @new_value: new value of link, bearer, or media setting * @cmd: which link, bearer, or media attribute to set (TIPC_CMD_SET_LINK_*) * * Caller must hold 'tipc_net_lock' to ensure link/bearer/media is not deleted. * * Returns 0 if value updated and negative value on error. */ static int link_cmd_set_value(const char *name, u32 new_value, u16 cmd) { struct tipc_node *node; struct tipc_link *l_ptr; struct tipc_bearer *b_ptr; struct tipc_media *m_ptr; int bearer_id; int res = 0; node = tipc_link_find_owner(name, &bearer_id); if (node) { tipc_node_lock(node); l_ptr = node->links[bearer_id]; if (l_ptr) { switch (cmd) { case TIPC_CMD_SET_LINK_TOL: link_set_supervision_props(l_ptr, new_value); tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, new_value, 0, 0); break; case TIPC_CMD_SET_LINK_PRI: l_ptr->priority = new_value; tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, new_value, 0); break; case TIPC_CMD_SET_LINK_WINDOW: tipc_link_set_queue_limits(l_ptr, new_value); break; default: res = -EINVAL; break; } } tipc_node_unlock(node); return res; } b_ptr = tipc_bearer_find(name); if (b_ptr) { switch (cmd) { case TIPC_CMD_SET_LINK_TOL: b_ptr->tolerance = new_value; break; case TIPC_CMD_SET_LINK_PRI: b_ptr->priority = new_value; break; case TIPC_CMD_SET_LINK_WINDOW: b_ptr->window = new_value; break; default: res = -EINVAL; break; } return res; } m_ptr = tipc_media_find(name); if (!m_ptr) return -ENODEV; switch (cmd) { case TIPC_CMD_SET_LINK_TOL: m_ptr->tolerance = new_value; break; case TIPC_CMD_SET_LINK_PRI: m_ptr->priority = new_value; break; case TIPC_CMD_SET_LINK_WINDOW: m_ptr->window = new_value; break; default: res = -EINVAL; break; } return res; } struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space, u16 cmd) { struct tipc_link_config *args; u32 new_value; int res; if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_CONFIG)) return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); args = (struct tipc_link_config *)TLV_DATA(req_tlv_area); new_value = ntohl(args->value); if (!link_value_is_valid(cmd, new_value)) return tipc_cfg_reply_error_string( "cannot change, value invalid"); if (!strcmp(args->name, tipc_bclink_name)) { if ((cmd == TIPC_CMD_SET_LINK_WINDOW) && (tipc_bclink_set_queue_limits(new_value) == 0)) return tipc_cfg_reply_none(); return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED " (cannot change setting on broadcast link)"); } read_lock_bh(&tipc_net_lock); res = link_cmd_set_value(args->name, new_value, cmd); read_unlock_bh(&tipc_net_lock); if (res) return tipc_cfg_reply_error_string("cannot change link setting"); return tipc_cfg_reply_none(); } /** * link_reset_statistics - reset link statistics * @l_ptr: pointer to link */ static void link_reset_statistics(struct tipc_link *l_ptr) { memset(&l_ptr->stats, 0, sizeof(l_ptr->stats)); l_ptr->stats.sent_info = l_ptr->next_out_no; l_ptr->stats.recv_info = l_ptr->next_in_no; } struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space) { char *link_name; struct tipc_link *l_ptr; struct tipc_node *node; unsigned int bearer_id; if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME)) return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); link_name = (char *)TLV_DATA(req_tlv_area); if (!strcmp(link_name, tipc_bclink_name)) { if (tipc_bclink_reset_stats()) return tipc_cfg_reply_error_string("link not found"); return tipc_cfg_reply_none(); } read_lock_bh(&tipc_net_lock); node = tipc_link_find_owner(link_name, &bearer_id); if (!node) { read_unlock_bh(&tipc_net_lock); return tipc_cfg_reply_error_string("link not found"); } tipc_node_lock(node); l_ptr = node->links[bearer_id]; if (!l_ptr) { tipc_node_unlock(node); read_unlock_bh(&tipc_net_lock); return tipc_cfg_reply_error_string("link not found"); } link_reset_statistics(l_ptr); tipc_node_unlock(node); read_unlock_bh(&tipc_net_lock); return tipc_cfg_reply_none(); } /** * percent - convert count to a percentage of total (rounding up or down) */ static u32 percent(u32 count, u32 total) { return (count * 100 + (total / 2)) / total; } /** * tipc_link_stats - print link statistics * @name: link name * @buf: print buffer area * @buf_size: size of print buffer area * * Returns length of print buffer data string (or 0 if error) */ static int tipc_link_stats(const char *name, char *buf, const u32 buf_size) { struct tipc_link *l; struct tipc_stats *s; struct tipc_node *node; char *status; u32 profile_total = 0; unsigned int bearer_id; int ret; if (!strcmp(name, tipc_bclink_name)) return tipc_bclink_stats(buf, buf_size); read_lock_bh(&tipc_net_lock); node = tipc_link_find_owner(name, &bearer_id); if (!node) { read_unlock_bh(&tipc_net_lock); return 0; } tipc_node_lock(node); l = node->links[bearer_id]; if (!l) { tipc_node_unlock(node); read_unlock_bh(&tipc_net_lock); return 0; } s = &l->stats; if (tipc_link_is_active(l)) status = "ACTIVE"; else if (tipc_link_is_up(l)) status = "STANDBY"; else status = "DEFUNCT"; ret = tipc_snprintf(buf, buf_size, "Link <%s>\n" " %s MTU:%u Priority:%u Tolerance:%u ms" " Window:%u packets\n", l->name, status, l->max_pkt, l->priority, l->tolerance, l->queue_limit[0]); ret += tipc_snprintf(buf + ret, buf_size - ret, " RX packets:%u fragments:%u/%u bundles:%u/%u\n", l->next_in_no - s->recv_info, s->recv_fragments, s->recv_fragmented, s->recv_bundles, s->recv_bundled); ret += tipc_snprintf(buf + ret, buf_size - ret, " TX packets:%u fragments:%u/%u bundles:%u/%u\n", l->next_out_no - s->sent_info, s->sent_fragments, s->sent_fragmented, s->sent_bundles, s->sent_bundled); profile_total = s->msg_length_counts; if (!profile_total) profile_total = 1; ret += tipc_snprintf(buf + ret, buf_size - ret, " TX profile sample:%u packets average:%u octets\n" " 0-64:%u%% -256:%u%% -1024:%u%% -4096:%u%% " "-16384:%u%% -32768:%u%% -66000:%u%%\n", s->msg_length_counts, s->msg_lengths_total / profile_total, percent(s->msg_length_profile[0], profile_total), percent(s->msg_length_profile[1], profile_total), percent(s->msg_length_profile[2], profile_total), percent(s->msg_length_profile[3], profile_total), percent(s->msg_length_profile[4], profile_total), percent(s->msg_length_profile[5], profile_total), percent(s->msg_length_profile[6], profile_total)); ret += tipc_snprintf(buf + ret, buf_size - ret, " RX states:%u probes:%u naks:%u defs:%u" " dups:%u\n", s->recv_states, s->recv_probes, s->recv_nacks, s->deferred_recv, s->duplicates); ret += tipc_snprintf(buf + ret, buf_size - ret, " TX states:%u probes:%u naks:%u acks:%u" " dups:%u\n", s->sent_states, s->sent_probes, s->sent_nacks, s->sent_acks, s->retransmitted); ret += tipc_snprintf(buf + ret, buf_size - ret, " Congestion link:%u Send queue" " max:%u avg:%u\n", s->link_congs, s->max_queue_sz, s->queue_sz_counts ? (s->accu_queue_sz / s->queue_sz_counts) : 0); tipc_node_unlock(node); read_unlock_bh(&tipc_net_lock); return ret; } struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space) { struct sk_buff *buf; struct tlv_desc *rep_tlv; int str_len; int pb_len; char *pb; if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME)) return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); buf = tipc_cfg_reply_alloc(TLV_SPACE(ULTRA_STRING_MAX_LEN)); if (!buf) return NULL; rep_tlv = (struct tlv_desc *)buf->data; pb = TLV_DATA(rep_tlv); pb_len = ULTRA_STRING_MAX_LEN; str_len = tipc_link_stats((char *)TLV_DATA(req_tlv_area), pb, pb_len); if (!str_len) { kfree_skb(buf); return tipc_cfg_reply_error_string("link not found"); } str_len += 1; /* for "\0" */ skb_put(buf, TLV_SPACE(str_len)); TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len); return buf; } /** * tipc_link_get_max_pkt - get maximum packet size to use when sending to destination * @dest: network address of destination node * @selector: used to select from set of active links * * If no active link can be found, uses default maximum packet size. */ u32 tipc_link_get_max_pkt(u32 dest, u32 selector) { struct tipc_node *n_ptr; struct tipc_link *l_ptr; u32 res = MAX_PKT_DEFAULT; if (dest == tipc_own_addr) return MAX_MSG_SIZE; read_lock_bh(&tipc_net_lock); n_ptr = tipc_node_find(dest); if (n_ptr) { tipc_node_lock(n_ptr); l_ptr = n_ptr->active_links[selector & 1]; if (l_ptr) res = l_ptr->max_pkt; tipc_node_unlock(n_ptr); } read_unlock_bh(&tipc_net_lock); return res; } static void link_print(struct tipc_link *l_ptr, const char *str) { pr_info("%s Link %x<%s>:", str, l_ptr->addr, l_ptr->b_ptr->name); if (link_working_unknown(l_ptr)) pr_cont(":WU\n"); else if (link_reset_reset(l_ptr)) pr_cont(":RR\n"); else if (link_reset_unknown(l_ptr)) pr_cont(":RU\n"); else if (link_working_working(l_ptr)) pr_cont(":WW\n"); else pr_cont("\n"); }