diff options
Diffstat (limited to 'net/tipc/link.c')
| -rw-r--r-- | net/tipc/link.c | 2738 |
1 files changed, 2738 insertions, 0 deletions
diff --git a/net/tipc/link.c b/net/tipc/link.c new file mode 100644 index 00000000000..ad2c57f5868 --- /dev/null +++ b/net/tipc/link.c @@ -0,0 +1,2738 @@ +/* + * 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 "socket.h" +#include "name_distr.h" +#include "discover.h" +#include "config.h" + +#include <linux/pkt_sched.h> + +/* + * 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 tipc_link_proto_rcv(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 tipc_link_iovec_long_xmit(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 tipc_link_frag_xmit(struct tipc_link *l_ptr, struct sk_buff *buf); +static void tipc_link_sync_xmit(struct tipc_link *l); +static void tipc_link_sync_rcv(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) +{ + struct tipc_bearer *b_ptr; + u32 max_pkt; + + rcu_read_lock(); + b_ptr = rcu_dereference_rtnl(bearer_list[l_ptr->bearer_id]); + if (!b_ptr) { + rcu_read_unlock(); + return; + } + max_pkt = (b_ptr->mtu & ~3); + rcu_read_unlock(); + + 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->bearer_id = b_ptr->identity; + 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); + + l_ptr->net_plane = b_ptr->net_plane; + 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; + + rcu_read_lock(); + list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) { + tipc_node_lock(n_ptr); + 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); + tipc_node_unlock(n_ptr); + + /* 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; + tipc_node_unlock(n_ptr); + del_timer_sync(&l_ptr->timer); + } + continue; + } + tipc_node_unlock(n_ptr); + } + rcu_read_unlock(); +} + +/** + * 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 (!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; + tipc_port_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_buf); + l_ptr->reasm_buf = 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->bearer_id, 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; + + rcu_read_lock(); + list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) { + tipc_node_lock(n_ptr); + l_ptr = n_ptr->links[bearer_id]; + if (l_ptr) + tipc_link_reset(l_ptr); + tipc_node_unlock(n_ptr); + } + rcu_read_unlock(); +} + +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->bearer_id, 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_proto_xmit(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_proto_xmit(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_proto_xmit(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_proto_xmit(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_proto_xmit(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_proto_xmit(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_proto_xmit(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_proto_xmit(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_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); + l_ptr->fsm_msg_cnt++; + if (l_ptr->owner->working_links == 1) + tipc_link_sync_xmit(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_proto_xmit(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_proto_xmit(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_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0, 0); + l_ptr->fsm_msg_cnt++; + if (l_ptr->owner->working_links == 1) + tipc_link_sync_xmit(l_ptr); + link_set_timer(l_ptr, cont_intv); + break; + case RESET_MSG: + break; + case TIMEOUT_EVT: + tipc_link_proto_xmit(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_xmit() is the 'full path' for messages, called from + * inside TIPC when the 'fast path' in tipc_send_xmit + * has failed, and from link_send() + */ +int __tipc_link_xmit(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 tipc_link_frag_xmit(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->bearer_id, 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_xmit(): same as __tipc_link_xmit(), 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_xmit(struct sk_buff *buf, u32 dest, u32 selector) +{ + struct tipc_link *l_ptr; + struct tipc_node *n_ptr; + int res = -ELINKCONG; + + 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_xmit(l_ptr, buf); + else + kfree_skb(buf); + tipc_node_unlock(n_ptr); + } else { + kfree_skb(buf); + } + return res; +} + +/* + * tipc_link_sync_xmit - 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_sync_xmit(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_sync_rcv - 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_sync_rcv(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_names_xmit - 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_names_xmit(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; + + 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); + } + + /* 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); + } +} + +/* + * tipc_link_xmit_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 tipc_link_xmit_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->bearer_id, buf, + &l_ptr->media_addr); + l_ptr->unacked_window = 0; + return res; + } + else + *used_max_pkt = l_ptr->max_pkt; + } + return __tipc_link_xmit(l_ptr, buf); /* All other cases */ +} + +/* + * tipc_link_iovec_xmit_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_iovec_xmit_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; + + 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 = tipc_link_xmit_fast(l_ptr, buf, + &sender->max_pkt); +exit: + tipc_node_unlock(node); + 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); + + + if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt) + goto again; + + return tipc_link_iovec_long_xmit(sender, msg_sect, + len, destaddr); + } + tipc_node_unlock(node); + } + + /* Couldn't find a link to the destination node */ + kfree_skb(buf); + tipc_port_iovec_reject(sender, hdr, msg_sect, len, TIPC_ERR_NO_NODE); + return -ENETUNREACH; +} + +/* + * tipc_link_iovec_long_xmit(): 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 tipc_link_iovec_long_xmit(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); + tipc_port_iovec_reject(sender, hdr, msg_sect, len, + TIPC_ERR_NO_NODE); + return -ENETUNREACH; + } + + /* 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->bearer_id, 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->bearer_id, 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->bearer_id, 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); +} + +void tipc_link_reset_all(struct tipc_node *node) +{ + char addr_string[16]; + u32 i; + + tipc_node_lock(node); + + pr_warn("Resetting all links to %s\n", + tipc_addr_string_fill(addr_string, node->addr)); + + for (i = 0; i < MAX_BEARERS; i++) { + if (node->links[i]) { + link_print(node->links[i], "Resetting link\n"); + tipc_link_reset(node->links[i]); + } + } + + tipc_node_unlock(node); +} + +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_node_unlock(n_ptr); + + tipc_bclink_set_flags(TIPC_BCLINK_RESET); + 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->bearer_id, 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 this packet comes from the defer queue, the skb has already + * been validated + */ + if (unlikely(TIPC_SKB_CB(buf)->deferred)) + return 1; + + 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 + * @b_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) +{ + 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 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_rcv(buf, b_ptr); + else + tipc_bclink_rcv(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->action_flags & TIPC_WAIT_PEER_LINKS_DOWN) && + msg_user(msg) == LINK_PROTOCOL && + (msg_type(msg) == RESET_MSG || + msg_type(msg) == ACTIVATE_MSG) && + !msg_redundant_link(msg)) + n_ptr->action_flags &= ~TIPC_WAIT_PEER_LINKS_DOWN; + + if (tipc_node_blocked(n_ptr)) + 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_proto_xmit(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) { + tipc_link_proto_rcv(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) { + l_ptr->stats.recv_fragments++; + if (tipc_buf_append(&l_ptr->reasm_buf, &buf)) { + l_ptr->stats.recv_fragmented++; + msg = buf_msg(buf); + } else { + if (!l_ptr->reasm_buf) + 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_sk_rcv(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_bundle_rcv(buf); + continue; + case NAME_DISTRIBUTOR: + n_ptr->bclink.recv_permitted = true; + tipc_node_unlock(n_ptr); + tipc_named_rcv(buf); + continue; + case CONN_MANAGER: + tipc_node_unlock(n_ptr); + tipc_port_proto_rcv(buf); + continue; + case BCAST_PROTOCOL: + tipc_link_sync_rcv(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); + } +} + +/** + * 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)) { + tipc_link_proto_rcv(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++; + TIPC_SKB_CB(buf)->deferred = true; + if ((l_ptr->deferred_inqueue_sz % 16) == 1) + tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0, 0); + } else + l_ptr->stats.duplicates++; +} + +/* + * Send protocol message to the other endpoint. + */ +void tipc_link_proto_xmit(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 ((tipc_node_blocked(l_ptr->owner)) && (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->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->bearer_id, 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 tipc_link_proto_rcv(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; + + if (l_ptr->net_plane != msg_net_plane(msg)) + if (tipc_own_addr > msg_prevnode(msg)) + l_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->action_flags |= TIPC_WAIT_OWN_LINKS_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; + } + + /* Record reception; force mismatch at next timeout: */ + l_ptr->checkpoint--; + + 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_proto_xmit(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_xmit(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_xmit(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_queue_xmit(): 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_queue_xmit(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_xmit(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_buf_append(&l_ptr->reasm_buf, &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_bundle_rcv(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: + */ + +/* + * tipc_link_frag_xmit: Entry for buffers needing fragmentation. + * The buffer is complete, inclusive total message length. + * Returns user data length. + */ +static int tipc_link_frag_xmit(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; +} + +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. + * + * 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 *found_node = 0; + int i; + + *bearer_id = 0; + rcu_read_lock(); + list_for_each_entry_rcu(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; + } + rcu_read_unlock(); + + 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 RTNL 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_proto_xmit(l_ptr, STATE_MSG, 0, 0, + new_value, 0, 0); + break; + case TIPC_CMD_SET_LINK_PRI: + l_ptr->priority = new_value; + tipc_link_proto_xmit(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)"); + } + + res = link_cmd_set_value(args->name, new_value, cmd); + 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(); + } + node = tipc_link_find_owner(link_name, &bearer_id); + if (!node) + 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); + return tipc_cfg_reply_error_string("link not found"); + } + link_reset_statistics(l_ptr); + tipc_node_unlock(node); + 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); + + node = tipc_link_find_owner(name, &bearer_id); + if (!node) + return 0; + + tipc_node_lock(node); + + l = node->links[bearer_id]; + if (!l) { + tipc_node_unlock(node); + 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); + 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; + + 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); + } + return res; +} + +static void link_print(struct tipc_link *l_ptr, const char *str) +{ + struct tipc_bearer *b_ptr; + + rcu_read_lock(); + b_ptr = rcu_dereference_rtnl(bearer_list[l_ptr->bearer_id]); + if (b_ptr) + pr_info("%s Link %x<%s>:", str, l_ptr->addr, b_ptr->name); + rcu_read_unlock(); + + 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"); +} |