/* * net/tipc/link.c: TIPC link code * * Copyright (c) 1996-2007, Ericsson AB * Copyright (c) 2004-2007, 2010-2011, 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" /* * 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 /** * struct link_name - deconstructed link name * @addr_local: network address of node at this end * @if_local: name of interface at this end * @addr_peer: network address of node at far end * @if_peer: name of interface at far end */ struct link_name { u32 addr_local; char if_local[TIPC_MAX_IF_NAME]; u32 addr_peer; char if_peer[TIPC_MAX_IF_NAME]; }; static void link_handle_out_of_seq_msg(struct link *l_ptr, struct sk_buff *buf); static void link_recv_proto_msg(struct link *l_ptr, struct sk_buff *buf); static int link_recv_changeover_msg(struct link **l_ptr, struct sk_buff **buf); static void link_set_supervision_props(struct link *l_ptr, u32 tolerance); static int link_send_sections_long(struct tipc_port *sender, struct iovec const *msg_sect, u32 num_sect, unsigned int total_len, u32 destnode); static void link_check_defragm_bufs(struct link *l_ptr); static void link_state_event(struct link *l_ptr, u32 event); static void link_reset_statistics(struct link *l_ptr); static void link_print(struct link *l_ptr, const char *str); static void link_start(struct link *l_ptr); static int link_send_long_buf(struct link *l_ptr, 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 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 link *l_ptr) { if (l_ptr->next_out) return msg_seqno(buf_msg(l_ptr->next_out)); return mod(l_ptr->next_out_no); } static u32 link_last_sent(struct 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 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 link *l_ptr) { return (l_ptr->owner->active_links[0] == l_ptr) || (l_ptr->owner->active_links[1] == l_ptr); } /** * link_name_validate - validate & (optionally) deconstruct link name * @name - ptr to link name string * @name_parts - ptr to area for link name components (or NULL if not needed) * * Returns 1 if link name is valid, otherwise 0. */ static int link_name_validate(const char *name, struct link_name *name_parts) { char name_copy[TIPC_MAX_LINK_NAME]; char *addr_local; char *if_local; char *addr_peer; char *if_peer; char dummy; u32 z_local, c_local, n_local; u32 z_peer, c_peer, n_peer; u32 if_local_len; u32 if_peer_len; /* copy link name & ensure length is OK */ name_copy[TIPC_MAX_LINK_NAME - 1] = 0; /* need above in case non-Posix strncpy() doesn't pad with nulls */ strncpy(name_copy, name, TIPC_MAX_LINK_NAME); if (name_copy[TIPC_MAX_LINK_NAME - 1] != 0) return 0; /* ensure all component parts of link name are present */ addr_local = name_copy; if_local = strchr(addr_local, ':'); if (if_local == NULL) return 0; *(if_local++) = 0; addr_peer = strchr(if_local, '-'); if (addr_peer == NULL) return 0; *(addr_peer++) = 0; if_local_len = addr_peer - if_local; if_peer = strchr(addr_peer, ':'); if (if_peer == NULL) return 0; *(if_peer++) = 0; if_peer_len = strlen(if_peer) + 1; /* validate component parts of link name */ if ((sscanf(addr_local, "%u.%u.%u%c", &z_local, &c_local, &n_local, &dummy) != 3) || (sscanf(addr_peer, "%u.%u.%u%c", &z_peer, &c_peer, &n_peer, &dummy) != 3) || (z_local > 255) || (c_local > 4095) || (n_local > 4095) || (z_peer > 255) || (c_peer > 4095) || (n_peer > 4095) || (if_local_len <= 1) || (if_local_len > TIPC_MAX_IF_NAME) || (if_peer_len <= 1) || (if_peer_len > TIPC_MAX_IF_NAME) || (strspn(if_local, tipc_alphabet) != (if_local_len - 1)) || (strspn(if_peer, tipc_alphabet) != (if_peer_len - 1))) return 0; /* return link name components, if necessary */ if (name_parts) { name_parts->addr_local = tipc_addr(z_local, c_local, n_local); strcpy(name_parts->if_local, if_local); name_parts->addr_peer = tipc_addr(z_peer, c_peer, n_peer); strcpy(name_parts->if_peer, if_peer); } return 1; } /** * link_timeout - handle expiration of link timer * @l_ptr: pointer to link * * This routine must not grab "tipc_net_lock" to avoid a potential deadlock conflict * with tipc_link_delete(). (There is no risk that the node will be deleted by * another thread because tipc_link_delete() always cancels the link timer before * tipc_node_delete() is called.) */ static void link_timeout(struct 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_check_defragm_bufs(l_ptr); 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 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 link *tipc_link_create(struct tipc_node *n_ptr, struct tipc_bearer *b_ptr, const struct tipc_media_addr *media_addr) { struct 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); 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); 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) { 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); list_add_tail(&l_ptr->link_list, &b_ptr->links); tipc_k_signal((Handler)link_start, (unsigned long)l_ptr); return l_ptr; } /** * tipc_link_delete - delete a link * @l_ptr: pointer to link * * Note: 'tipc_net_lock' is write_locked, bearer is locked. * This routine must not grab the node lock until after link timer cancellation * to avoid a potential deadlock situation. */ void tipc_link_delete(struct link *l_ptr) { if (!l_ptr) { err("Attempt to delete non-existent link\n"); return; } k_cancel_timer(&l_ptr->timer); tipc_node_lock(l_ptr->owner); tipc_link_reset(l_ptr); tipc_node_detach_link(l_ptr->owner, l_ptr); tipc_link_stop(l_ptr); list_del_init(&l_ptr->link_list); tipc_node_unlock(l_ptr->owner); k_term_timer(&l_ptr->timer); kfree(l_ptr); } static void link_start(struct link *l_ptr) { tipc_node_lock(l_ptr->owner); link_state_event(l_ptr, STARTING_EVT); tipc_node_unlock(l_ptr->owner); } /** * 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 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 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 link *l_ptr) { struct sk_buff *buf = l_ptr->first_out; struct sk_buff *next; while (buf) { next = buf->next; buf_discard(buf); buf = next; } 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 link *l_ptr) { struct sk_buff *buf = l_ptr->defragm_buf; struct sk_buff *next; while (buf) { next = buf->next; buf_discard(buf); buf = next; } l_ptr->defragm_buf = NULL; } /** * tipc_link_stop - purge all inbound and outbound messages associated with link * @l_ptr: pointer to link */ void tipc_link_stop(struct link *l_ptr) { struct sk_buff *buf; struct sk_buff *next; buf = l_ptr->oldest_deferred_in; while (buf) { next = buf->next; buf_discard(buf); buf = next; } buf = l_ptr->first_out; while (buf) { next = buf->next; buf_discard(buf); buf = next; } tipc_link_reset_fragments(l_ptr); buf_discard(l_ptr->proto_msg_queue); l_ptr->proto_msg_queue = NULL; } void tipc_link_reset(struct link *l_ptr) { struct sk_buff *buf; 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->owner->permit_changeover) { l_ptr->reset_checkpoint = checkpoint; l_ptr->exp_msg_count = START_CHANGEOVER; } /* Clean up all queues: */ link_release_outqueue(l_ptr); buf_discard(l_ptr->proto_msg_queue); l_ptr->proto_msg_queue = NULL; buf = l_ptr->oldest_deferred_in; while (buf) { struct sk_buff *next = buf->next; buf_discard(buf); buf = next; } 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); } static void link_activate(struct 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 link *l_ptr, unsigned event) { struct link *other; u32 cont_intv = l_ptr->continuity_interval; if (!l_ptr->started && (event != STARTING_EVT)) return; /* Not yet. */ if (link_blocked(l_ptr)) { if (event == TIMEOUT_EVT) link_set_timer(l_ptr, cont_intv); return; /* Changeover going on */ } 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: info("Resetting link <%s>, requested by peer\n", 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: err("Unknown link event %u in WW state\n", 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: info("Resetting link <%s>, requested by peer " "while probing\n", 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 */ warn("Resetting link <%s>, peer not responding\n", 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: err("Unknown link event %u in WU state\n", 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++; 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->started = 1; /* 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: err("Unknown link event %u in RU state\n", 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++; 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: err("Unknown link event %u in RR state\n", event); } break; default: 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 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); buf_discard(buf); l_ptr->stats.sent_bundled++; return 1; } static void link_add_to_outqueue(struct 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 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 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; msg_set_prevnode(msg, tipc_own_addr); /* If routed message */ /* 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); buf_discard(buf); return -ELINKCONG; } buf_discard(buf); if (imp > CONN_MANAGER) { warn("Resetting link <%s>, send queue full", 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(!tipc_bearer_congested(l_ptr->b_ptr, l_ptr) && !link_congested(l_ptr))) { link_add_to_outqueue(l_ptr, buf, msg); if (likely(tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr))) { l_ptr->unacked_window = 0; } else { tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); l_ptr->stats.bearer_congs++; l_ptr->next_out = buf; } 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)) { tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr); 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); tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr); 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 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 buf_discard(buf); tipc_node_unlock(n_ptr); } else { buf_discard(buf); } read_unlock_bh(&tipc_net_lock); return res; } /* * 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 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); buf_discard(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 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)) { if (likely(list_empty(&l_ptr->b_ptr->cong_links))) { link_add_to_outqueue(l_ptr, buf, msg); if (likely(tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr))) { l_ptr->unacked_window = 0; return res; } tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); l_ptr->stats.bearer_congs++; l_ptr->next_out = buf; return res; } } else *used_max_pkt = l_ptr->max_pkt; } return tipc_link_send_buf(l_ptr, buf); /* All other cases */ } /* * tipc_send_buf_fast: Entry for data messages where the * destination node is known and the header is complete, * inclusive total message length. * Returns user data length. */ int tipc_send_buf_fast(struct sk_buff *buf, u32 destnode) { struct link *l_ptr; struct tipc_node *n_ptr; int res; u32 selector = msg_origport(buf_msg(buf)) & 1; u32 dummy; read_lock_bh(&tipc_net_lock); n_ptr = tipc_node_find(destnode); if (likely(n_ptr)) { tipc_node_lock(n_ptr); l_ptr = n_ptr->active_links[selector]; if (likely(l_ptr)) { res = link_send_buf_fast(l_ptr, buf, &dummy); tipc_node_unlock(n_ptr); read_unlock_bh(&tipc_net_lock); return res; } tipc_node_unlock(n_ptr); } read_unlock_bh(&tipc_net_lock); res = msg_data_sz(buf_msg(buf)); tipc_reject_msg(buf, TIPC_ERR_NO_NODE); return res; } /* * 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, const u32 num_sect, unsigned int total_len, u32 destaddr) { struct tipc_msg *hdr = &sender->phdr; struct 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, num_sect, total_len, sender->max_pkt, !sender->user_port, &buf); 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 build request was invalid */ if (unlikely(res < 0)) goto exit; /* Exit if link (or bearer) is congested */ if (link_congested(l_ptr) || !list_empty(&l_ptr->b_ptr->cong_links)) { 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, num_sect, total_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, num_sect, total_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, u32 num_sect, unsigned int total_len, u32 destaddr) { struct link *l_ptr; struct tipc_node *node; struct tipc_msg *hdr = &sender->phdr; u32 dsz = total_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 *sect_crs; int curr_sect; u32 fragm_no; 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 = (const unchar *)msg_sect[curr_sect].iov_base; } if (sect_rest < fragm_rest) sz = sect_rest; else sz = fragm_rest; if (likely(!sender->user_port)) { if (copy_from_user(buf->data + fragm_crs, sect_crs, sz)) { error: for (; buf_chain; buf_chain = buf) { buf = buf_chain->next; buf_discard(buf_chain); } return -EFAULT; } } else skb_copy_to_linear_data_offset(buf, fragm_crs, sect_crs, sz); 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) 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); for (; buf_chain; buf_chain = buf) { buf = buf_chain->next; buf_discard(buf_chain); } goto again; } } else { reject: for (; buf_chain; buf_chain = buf) { buf = buf_chain->next; buf_discard(buf_chain); } return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect, total_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 */ u32 tipc_link_push_packet(struct 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 = msg_seqno(buf_msg(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); if (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; } else { l_ptr->stats.bearer_congs++; return PUSH_FAILED; } } /* 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); if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { l_ptr->unacked_window = 0; buf_discard(buf); l_ptr->proto_msg_queue = NULL; return 0; } else { l_ptr->stats.bearer_congs++; return PUSH_FAILED; } } /* 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 = msg_seqno(buf_msg(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); if (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; } else { l_ptr->stats.bearer_congs++; return PUSH_FAILED; } } } return PUSH_FINISHED; } /* * push_queue(): push out the unsent messages of a link where * congestion has abated. Node is locked */ void tipc_link_push_queue(struct link *l_ptr) { u32 res; if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) return; do { res = tipc_link_push_packet(l_ptr); } while (!res); if (res == PUSH_FAILED) tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); } 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); 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 link *l_ptr, struct sk_buff *buf) { struct tipc_msg *msg = buf_msg(buf); 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]; info("Msg seq number: %u, ", msg_seqno(msg)); info("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); info("Multicast link info for %s\n", addr_string); info("Supported: %d, ", n_ptr->bclink.supported); info("Acked: %u\n", n_ptr->bclink.acked); info("Last in: %u, ", n_ptr->bclink.last_in); info("Gap after: %u, ", n_ptr->bclink.gap_after); info("Gap to: %u\n", n_ptr->bclink.gap_to); info("Nack sync: %u\n\n", n_ptr->bclink.nack_sync); 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 link *l_ptr, struct sk_buff *buf, u32 retransmits) { struct tipc_msg *msg; if (!buf) return; msg = buf_msg(buf); if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) { if (l_ptr->retransm_queue_size == 0) { l_ptr->retransm_queue_head = msg_seqno(msg); l_ptr->retransm_queue_size = retransmits; } else { err("Unexpected retransmit on link %s (qsize=%d)\n", l_ptr->name, l_ptr->retransm_queue_size); } return; } else { /* Detect repeated retransmit failures on uncongested bearer */ 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); if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { buf = buf->next; retransmits--; l_ptr->stats.retransmitted++; } else { tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); l_ptr->stats.bearer_congs++; l_ptr->retransm_queue_head = msg_seqno(buf_msg(buf)); l_ptr->retransm_queue_size = retransmits; return; } } 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 link *l_ptr, struct sk_buff *buf) { u32 seq_no; if (l_ptr->oldest_deferred_in == NULL) return buf; seq_no = msg_seqno(buf_msg(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_recv_msg - process TIPC 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_recv_msg(struct sk_buff *head, struct tipc_bearer *b_ptr) { read_lock_bh(&tipc_net_lock); while (head) { struct tipc_node *n_ptr; struct link *l_ptr; struct sk_buff *crs; struct sk_buff *buf = head; struct tipc_msg *msg; u32 seq_no; u32 ackd; u32 released = 0; int type; head = head->next; /* Ensure bearer is still enabled */ if (unlikely(!b_ptr->active)) goto cont; /* Ensure message is well-formed */ if (unlikely(!link_recv_buf_validate(buf))) goto cont; /* Ensure message data is a single contiguous unit */ if (unlikely(buf_linearize(buf))) goto cont; /* 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 cont; /* Locate neighboring node that sent message */ n_ptr = tipc_node_find(msg_prevnode(msg)); if (unlikely(!n_ptr)) goto cont; 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)) { tipc_node_unlock(n_ptr); goto cont; } /* 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) { tipc_node_unlock(n_ptr); goto cont; } /* Validate message sequence number info */ seq_no = msg_seqno(msg); ackd = msg_ack(msg); /* Release acked messages */ if (less(n_ptr->bclink.acked, msg_bcast_ack(msg))) { if (tipc_node_is_up(n_ptr) && n_ptr->bclink.supported) tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg)); } crs = l_ptr->first_out; while ((crs != l_ptr->next_out) && less_eq(msg_seqno(buf_msg(crs)), ackd)) { struct sk_buff *next = crs->next; buf_discard(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); } /* Now (finally!) process the incoming message */ protocol_check: if (likely(link_working_working(l_ptr))) { if (likely(seq_no == mod(l_ptr->next_in_no))) { l_ptr->next_in_no++; if (unlikely(l_ptr->oldest_deferred_in)) head = link_insert_deferred_queue(l_ptr, head); if (likely(msg_is_dest(msg, tipc_own_addr))) { deliver: if (likely(msg_isdata(msg))) { tipc_node_unlock(n_ptr); tipc_port_recv_msg(buf); continue; } switch (msg_user(msg)) { 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: 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 MSG_FRAGMENTER: l_ptr->stats.recv_fragments++; if (tipc_link_recv_fragment(&l_ptr->defragm_buf, &buf, &msg)) { l_ptr->stats.recv_fragmented++; goto deliver; } break; case CHANGEOVER_PROTOCOL: type = msg_type(msg); if (link_recv_changeover_msg(&l_ptr, &buf)) { msg = buf_msg(buf); seq_no = msg_seqno(msg); if (type == ORIGINAL_MSG) goto deliver; goto protocol_check; } break; default: buf_discard(buf); buf = NULL; break; } } tipc_node_unlock(n_ptr); tipc_net_route_msg(buf); continue; } link_handle_out_of_seq_msg(l_ptr, buf); head = link_insert_deferred_queue(l_ptr, head); tipc_node_unlock(n_ptr); continue; } 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; } link_state_event(l_ptr, TRAFFIC_MSG_EVT); if (link_working_working(l_ptr)) { /* Re-insert in front of queue */ buf->next = head; head = buf; tipc_node_unlock(n_ptr); continue; } tipc_node_unlock(n_ptr); cont: buf_discard(buf); } read_unlock_bh(&tipc_net_lock); } /* * link_defer_buf(): Sort a received out-of-sequence packet * into the deferred reception queue. * Returns the increase of the 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 *prev = NULL; struct sk_buff *crs = *head; u32 seq_no = msg_seqno(buf_msg(buf)); buf->next = NULL; /* Empty queue ? */ if (*head == NULL) { *head = *tail = buf; return 1; } /* Last ? */ if (less(msg_seqno(buf_msg(*tail)), seq_no)) { (*tail)->next = buf; *tail = buf; return 1; } /* Scan through queue and sort it in */ do { struct tipc_msg *msg = buf_msg(crs); if (less(seq_no, msg_seqno(msg))) { buf->next = crs; if (prev) prev->next = buf; else *head = buf; return 1; } if (seq_no == msg_seqno(msg)) break; prev = crs; crs = crs->next; } while (crs); /* Message is a duplicate of an existing message */ buf_discard(buf); return 0; } /** * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet */ static void link_handle_out_of_seq_msg(struct link *l_ptr, struct sk_buff *buf) { u32 seq_no = msg_seqno(buf_msg(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++; buf_discard(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 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; if (link_blocked(l_ptr)) return; /* Abort non-RESET send if communication with node is prohibited */ if ((l_ptr->owner->block_setup) && (msg_typ != RESET_MSG)) return; msg_set_type(msg, msg_typ); msg_set_net_plane(msg, l_ptr->b_ptr->net_plane); msg_set_bcast_ack(msg, mod(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 = msg_seqno(buf_msg(l_ptr->next_out)); msg_set_next_sent(msg, next_sent); if (l_ptr->oldest_deferred_in) { u32 rec = msg_seqno(buf_msg(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); /* Ensure sequence number will not fit : */ msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2))); /* Congestion? */ if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) { if (!l_ptr->proto_msg_queue) { l_ptr->proto_msg_queue = tipc_buf_acquire(sizeof(l_ptr->proto_msg)); } buf = l_ptr->proto_msg_queue; if (!buf) return; skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg)); return; } /* Message can be sent */ buf = tipc_buf_acquire(msg_size); if (!buf) return; skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg)); msg_set_size(buf_msg(buf), msg_size); if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) { l_ptr->unacked_window = 0; buf_discard(buf); return; } /* New congestion */ tipc_bearer_schedule(l_ptr->b_ptr, l_ptr); l_ptr->proto_msg_queue = buf; l_ptr->stats.bearer_congs++; } /* * 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 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); if (link_blocked(l_ptr)) 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); l_ptr->owner->permit_changeover = msg_redundant_link(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; } /* 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; } l_ptr->owner->bclink.supported = (max_pkt_info != 0); link_state_event(l_ptr, msg_type(msg)); l_ptr->peer_session = msg_session(msg); l_ptr->peer_bearer_id = msg_bearer_id(msg); /* Synchronize broadcast sequence numbers */ if (!tipc_node_redundant_links(l_ptr->owner)) l_ptr->owner->bclink.last_in = mod(msg_last_bcast(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)) { warn("Resetting link <%s>, priority change %u->%u\n", 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 */ tipc_bclink_check_gap(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: buf_discard(buf); } /* * tipc_link_tunnel(): Send one message via a link belonging to * another bearer. Owner node is locked. */ static void tipc_link_tunnel(struct link *l_ptr, struct tipc_msg *tunnel_hdr, struct tipc_msg *msg, u32 selector) { struct 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)) { warn("Link changeover error, " "tunnel link no longer available\n"); return; } msg_set_size(tunnel_hdr, length + INT_H_SIZE); buf = tipc_buf_acquire(length + INT_H_SIZE); if (!buf) { warn("Link changeover error, " "unable to send tunnel msg\n"); 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); } /* * changeover(): Send whole message queue via the remaining link * Owner node is locked. */ void tipc_link_changeover(struct link *l_ptr) { u32 msgcount = l_ptr->out_queue_size; struct sk_buff *crs = l_ptr->first_out; struct link *tunnel = l_ptr->owner->active_links[0]; struct tipc_msg tunnel_hdr; int split_bundles; if (!tunnel) return; if (!l_ptr->owner->permit_changeover) { warn("Link changeover error, " "peer did not permit changeover\n"); 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 { warn("Link changeover error, " "unable to send changeover msg\n"); } 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(l_ptr, &tunnel_hdr, m, msg_link_selector(m)); pos += align(msg_size(m)); m = (struct tipc_msg *)pos; } } else { tipc_link_tunnel(l_ptr, &tunnel_hdr, msg, msg_link_selector(msg)); } crs = crs->next; } } void tipc_link_send_duplicate(struct link *l_ptr, struct 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) { warn("Link changeover error, " "unable to send duplicate msg\n"); 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; } /* * link_recv_changeover_msg(): Receive tunneled packet sent * via other link. Node is locked. Return extracted buffer. */ static int link_recv_changeover_msg(struct link **l_ptr, struct sk_buff **buf) { struct sk_buff *tunnel_buf = *buf; struct link *dest_link; struct tipc_msg *msg; struct tipc_msg *tunnel_msg = buf_msg(tunnel_buf); u32 msg_typ = msg_type(tunnel_msg); u32 msg_count = msg_msgcnt(tunnel_msg); dest_link = (*l_ptr)->owner->links[msg_bearer_id(tunnel_msg)]; if (!dest_link) goto exit; if (dest_link == *l_ptr) { err("Unexpected changeover message on link <%s>\n", (*l_ptr)->name); goto exit; } *l_ptr = dest_link; msg = msg_get_wrapped(tunnel_msg); if (msg_typ == DUPLICATE_MSG) { if (less(msg_seqno(msg), mod(dest_link->next_in_no))) goto exit; *buf = buf_extract(tunnel_buf, INT_H_SIZE); if (*buf == NULL) { warn("Link changeover error, duplicate msg dropped\n"); goto exit; } buf_discard(tunnel_buf); return 1; } /* First original message ?: */ if (tipc_link_is_up(dest_link)) { info("Resetting link <%s>, changeover initiated by peer\n", dest_link->name); tipc_link_reset(dest_link); dest_link->exp_msg_count = msg_count; if (!msg_count) goto exit; } else if (dest_link->exp_msg_count == START_CHANGEOVER) { dest_link->exp_msg_count = msg_count; if (!msg_count) goto exit; } /* Receive original message */ if (dest_link->exp_msg_count == 0) { warn("Link switchover error, " "got too many tunnelled messages\n"); goto exit; } dest_link->exp_msg_count--; if (less(msg_seqno(msg), dest_link->reset_checkpoint)) { goto exit; } else { *buf = buf_extract(tunnel_buf, INT_H_SIZE); if (*buf != NULL) { buf_discard(tunnel_buf); return 1; } else { warn("Link changeover error, original msg dropped\n"); } } exit: *buf = NULL; buf_discard(tunnel_buf); return 0; } /* * 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) { warn("Link unable to unbundle message(s)\n"); break; } pos += align(msg_size(buf_msg(obuf))); tipc_net_route_msg(obuf); } buf_discard(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 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) { buf_discard(buf); while (buf_chain) { buf = buf_chain; buf_chain = buf_chain->next; buf_discard(buf); } 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); } buf_discard(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; } /* * A pending message being re-assembled must store certain values * to handle subsequent fragments correctly. The following functions * help storing these values in unused, available fields in the * pending message. This makes dynamic memory allocation unnecessary. */ static void set_long_msg_seqno(struct sk_buff *buf, u32 seqno) { msg_set_seqno(buf_msg(buf), seqno); } static u32 get_fragm_size(struct sk_buff *buf) { return msg_ack(buf_msg(buf)); } static void set_fragm_size(struct sk_buff *buf, u32 sz) { msg_set_ack(buf_msg(buf), sz); } static u32 get_expected_frags(struct sk_buff *buf) { return msg_bcast_ack(buf_msg(buf)); } static void set_expected_frags(struct sk_buff *buf, u32 exp) { msg_set_bcast_ack(buf_msg(buf), exp); } static u32 get_timer_cnt(struct sk_buff *buf) { return msg_reroute_cnt(buf_msg(buf)); } static void incr_timer_cnt(struct sk_buff *buf) { msg_incr_reroute_cnt(buf_msg(buf)); } /* * tipc_link_recv_fragment(): Called with node lock on. Returns * the reassembled buffer if message is complete. */ int tipc_link_recv_fragment(struct sk_buff **pending, struct sk_buff **fb, struct tipc_msg **m) { struct sk_buff *prev = NULL; struct sk_buff *fbuf = *fb; struct tipc_msg *fragm = buf_msg(fbuf); struct sk_buff *pbuf = *pending; u32 long_msg_seq_no = msg_long_msgno(fragm); *fb = NULL; /* Is there an incomplete message waiting for this fragment? */ while (pbuf && ((msg_seqno(buf_msg(pbuf)) != long_msg_seq_no) || (msg_orignode(fragm) != msg_orignode(buf_msg(pbuf))))) { prev = pbuf; pbuf = pbuf->next; } if (!pbuf && (msg_type(fragm) == FIRST_FRAGMENT)) { struct tipc_msg *imsg = (struct tipc_msg *)msg_data(fragm); u32 msg_sz = msg_size(imsg); u32 fragm_sz = msg_data_sz(fragm); u32 exp_fragm_cnt = msg_sz/fragm_sz + !!(msg_sz % fragm_sz); u32 max = TIPC_MAX_USER_MSG_SIZE + NAMED_H_SIZE; if (msg_type(imsg) == TIPC_MCAST_MSG) max = TIPC_MAX_USER_MSG_SIZE + MCAST_H_SIZE; if (msg_size(imsg) > max) { buf_discard(fbuf); return 0; } pbuf = tipc_buf_acquire(msg_size(imsg)); if (pbuf != NULL) { pbuf->next = *pending; *pending = pbuf; skb_copy_to_linear_data(pbuf, imsg, msg_data_sz(fragm)); /* Prepare buffer for subsequent fragments. */ set_long_msg_seqno(pbuf, long_msg_seq_no); set_fragm_size(pbuf, fragm_sz); set_expected_frags(pbuf, exp_fragm_cnt - 1); } else { warn("Link unable to reassemble fragmented message\n"); } buf_discard(fbuf); return 0; } else if (pbuf && (msg_type(fragm) != FIRST_FRAGMENT)) { u32 dsz = msg_data_sz(fragm); u32 fsz = get_fragm_size(pbuf); u32 crs = ((msg_fragm_no(fragm) - 1) * fsz); u32 exp_frags = get_expected_frags(pbuf) - 1; skb_copy_to_linear_data_offset(pbuf, crs, msg_data(fragm), dsz); buf_discard(fbuf); /* Is message complete? */ if (exp_frags == 0) { if (prev) prev->next = pbuf->next; else *pending = pbuf->next; msg_reset_reroute_cnt(buf_msg(pbuf)); *fb = pbuf; *m = buf_msg(pbuf); return 1; } set_expected_frags(pbuf, exp_frags); return 0; } buf_discard(fbuf); return 0; } /** * link_check_defragm_bufs - flush stale incoming message fragments * @l_ptr: pointer to link */ static void link_check_defragm_bufs(struct link *l_ptr) { struct sk_buff *prev = NULL; struct sk_buff *next = NULL; struct sk_buff *buf = l_ptr->defragm_buf; if (!buf) return; if (!link_working_working(l_ptr)) return; while (buf) { u32 cnt = get_timer_cnt(buf); next = buf->next; if (cnt < 4) { incr_timer_cnt(buf); prev = buf; } else { if (prev) prev->next = buf->next; else l_ptr->defragm_buf = buf->next; buf_discard(buf); } buf = next; } } static void link_set_supervision_props(struct 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 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; } /** * link_find_link - locate link by name * @name - ptr to link name string * @node - ptr to area to be filled with ptr to associated node * * Caller must hold 'tipc_net_lock' to ensure node and bearer are not deleted; * this also prevents link deletion. * * Returns pointer to link (or 0 if invalid link name). */ static struct link *link_find_link(const char *name, struct tipc_node **node) { struct link_name link_name_parts; struct tipc_bearer *b_ptr; struct link *l_ptr; if (!link_name_validate(name, &link_name_parts)) return NULL; b_ptr = tipc_bearer_find_interface(link_name_parts.if_local); if (!b_ptr) return NULL; *node = tipc_node_find(link_name_parts.addr_peer); if (!*node) return NULL; l_ptr = (*node)->links[b_ptr->identity]; if (!l_ptr || strcmp(l_ptr->name, name)) return NULL; return l_ptr; } /** * 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 link *l_ptr; struct tipc_bearer *b_ptr; struct media *m_ptr; l_ptr = link_find_link(name, &node); if (l_ptr) { /* * acquire node lock for tipc_link_send_proto_msg(). * see "TIPC locking policy" in net.c. */ tipc_node_lock(node); 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; } tipc_node_unlock(node); return 0; } b_ptr = tipc_bearer_find(name); if (b_ptr) { switch (cmd) { case TIPC_CMD_SET_LINK_TOL: b_ptr->tolerance = new_value; return 0; case TIPC_CMD_SET_LINK_PRI: b_ptr->priority = new_value; return 0; case TIPC_CMD_SET_LINK_WINDOW: b_ptr->window = new_value; return 0; } return -EINVAL; } m_ptr = tipc_media_find(name); if (!m_ptr) return -ENODEV; switch (cmd) { case TIPC_CMD_SET_LINK_TOL: m_ptr->tolerance = new_value; return 0; case TIPC_CMD_SET_LINK_PRI: m_ptr->priority = new_value; return 0; case TIPC_CMD_SET_LINK_WINDOW: m_ptr->window = new_value; return 0; } return -EINVAL; } 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 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 link *l_ptr; struct tipc_node *node; 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); l_ptr = link_find_link(link_name, &node); if (!l_ptr) { read_unlock_bh(&tipc_net_lock); return tipc_cfg_reply_error_string("link not found"); } tipc_node_lock(node); 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 print_buf pb; struct link *l_ptr; struct tipc_node *node; char *status; u32 profile_total = 0; if (!strcmp(name, tipc_bclink_name)) return tipc_bclink_stats(buf, buf_size); tipc_printbuf_init(&pb, buf, buf_size); read_lock_bh(&tipc_net_lock); l_ptr = link_find_link(name, &node); if (!l_ptr) { read_unlock_bh(&tipc_net_lock); return 0; } tipc_node_lock(node); if (tipc_link_is_active(l_ptr)) status = "ACTIVE"; else if (tipc_link_is_up(l_ptr)) status = "STANDBY"; else status = "DEFUNCT"; tipc_printf(&pb, "Link <%s>\n" " %s MTU:%u Priority:%u Tolerance:%u ms" " Window:%u packets\n", l_ptr->name, status, l_ptr->max_pkt, l_ptr->priority, l_ptr->tolerance, l_ptr->queue_limit[0]); tipc_printf(&pb, " RX packets:%u fragments:%u/%u bundles:%u/%u\n", l_ptr->next_in_no - l_ptr->stats.recv_info, l_ptr->stats.recv_fragments, l_ptr->stats.recv_fragmented, l_ptr->stats.recv_bundles, l_ptr->stats.recv_bundled); tipc_printf(&pb, " TX packets:%u fragments:%u/%u bundles:%u/%u\n", l_ptr->next_out_no - l_ptr->stats.sent_info, l_ptr->stats.sent_fragments, l_ptr->stats.sent_fragmented, l_ptr->stats.sent_bundles, l_ptr->stats.sent_bundled); profile_total = l_ptr->stats.msg_length_counts; if (!profile_total) profile_total = 1; tipc_printf(&pb, " 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", l_ptr->stats.msg_length_counts, l_ptr->stats.msg_lengths_total / profile_total, percent(l_ptr->stats.msg_length_profile[0], profile_total), percent(l_ptr->stats.msg_length_profile[1], profile_total), percent(l_ptr->stats.msg_length_profile[2], profile_total), percent(l_ptr->stats.msg_length_profile[3], profile_total), percent(l_ptr->stats.msg_length_profile[4], profile_total), percent(l_ptr->stats.msg_length_profile[5], profile_total), percent(l_ptr->stats.msg_length_profile[6], profile_total)); tipc_printf(&pb, " RX states:%u probes:%u naks:%u defs:%u dups:%u\n", l_ptr->stats.recv_states, l_ptr->stats.recv_probes, l_ptr->stats.recv_nacks, l_ptr->stats.deferred_recv, l_ptr->stats.duplicates); tipc_printf(&pb, " TX states:%u probes:%u naks:%u acks:%u dups:%u\n", l_ptr->stats.sent_states, l_ptr->stats.sent_probes, l_ptr->stats.sent_nacks, l_ptr->stats.sent_acks, l_ptr->stats.retransmitted); tipc_printf(&pb, " Congestion bearer:%u link:%u Send queue max:%u avg:%u\n", l_ptr->stats.bearer_congs, l_ptr->stats.link_congs, l_ptr->stats.max_queue_sz, l_ptr->stats.queue_sz_counts ? (l_ptr->stats.accu_queue_sz / l_ptr->stats.queue_sz_counts) : 0); tipc_node_unlock(node); read_unlock_bh(&tipc_net_lock); return tipc_printbuf_validate(&pb); } #define MAX_LINK_STATS_INFO 2000 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; 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(MAX_LINK_STATS_INFO)); if (!buf) return NULL; rep_tlv = (struct tlv_desc *)buf->data; str_len = tipc_link_stats((char *)TLV_DATA(req_tlv_area), (char *)TLV_DATA(rep_tlv), MAX_LINK_STATS_INFO); if (!str_len) { buf_discard(buf); return tipc_cfg_reply_error_string("link not found"); } 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 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 link *l_ptr, const char *str) { char print_area[256]; struct print_buf pb; struct print_buf *buf = &pb; tipc_printbuf_init(buf, print_area, sizeof(print_area)); tipc_printf(buf, str); tipc_printf(buf, "Link %x<%s>:", l_ptr->addr, l_ptr->b_ptr->name); #ifdef CONFIG_TIPC_DEBUG if (link_reset_reset(l_ptr) || link_reset_unknown(l_ptr)) goto print_state; tipc_printf(buf, ": NXO(%u):", mod(l_ptr->next_out_no)); tipc_printf(buf, "NXI(%u):", mod(l_ptr->next_in_no)); tipc_printf(buf, "SQUE"); if (l_ptr->first_out) { tipc_printf(buf, "[%u..", msg_seqno(buf_msg(l_ptr->first_out))); if (l_ptr->next_out) tipc_printf(buf, "%u..", msg_seqno(buf_msg(l_ptr->next_out))); tipc_printf(buf, "%u]", msg_seqno(buf_msg(l_ptr->last_out))); if ((mod(msg_seqno(buf_msg(l_ptr->last_out)) - msg_seqno(buf_msg(l_ptr->first_out))) != (l_ptr->out_queue_size - 1)) || (l_ptr->last_out->next != NULL)) { tipc_printf(buf, "\nSend queue inconsistency\n"); tipc_printf(buf, "first_out= %p ", l_ptr->first_out); tipc_printf(buf, "next_out= %p ", l_ptr->next_out); tipc_printf(buf, "last_out= %p ", l_ptr->last_out); } } else tipc_printf(buf, "[]"); tipc_printf(buf, "SQSIZ(%u)", l_ptr->out_queue_size); if (l_ptr->oldest_deferred_in) { u32 o = msg_seqno(buf_msg(l_ptr->oldest_deferred_in)); u32 n = msg_seqno(buf_msg(l_ptr->newest_deferred_in)); tipc_printf(buf, ":RQUE[%u..%u]", o, n); if (l_ptr->deferred_inqueue_sz != mod((n + 1) - o)) { tipc_printf(buf, ":RQSIZ(%u)", l_ptr->deferred_inqueue_sz); } } print_state: #endif if (link_working_unknown(l_ptr)) tipc_printf(buf, ":WU"); else if (link_reset_reset(l_ptr)) tipc_printf(buf, ":RR"); else if (link_reset_unknown(l_ptr)) tipc_printf(buf, ":RU"); else if (link_working_working(l_ptr)) tipc_printf(buf, ":WW"); tipc_printf(buf, "\n"); tipc_printbuf_validate(buf); info("%s", print_area); }