- 根目录:
- net
- tipc
- link.c
/*
* 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 "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 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 void tipc_link_sync_xmit(struct tipc_link *l);
static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf);
static int tipc_link_input(struct tipc_link *l, struct sk_buff *buf);
static int tipc_link_prepare_input(struct tipc_link *l, 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;
__skb_queue_head_init(&l_ptr->waiting_sks);
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_user - schedule user for wakeup after congestion
* @link: congested link
* @oport: sending port
* @chain_sz: size of buffer chain that was attempted sent
* @imp: importance of message attempted sent
* Create pseudo msg to send back to user when congestion abates
*/
static bool link_schedule_user(struct tipc_link *link, u32 oport,
uint chain_sz, uint imp)
{
struct sk_buff *buf;
buf = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0, tipc_own_addr,
tipc_own_addr, oport, 0, 0);
if (!buf)
return false;
TIPC_SKB_CB(buf)->chain_sz = chain_sz;
TIPC_SKB_CB(buf)->chain_imp = imp;
__skb_queue_tail(&link->waiting_sks, buf);
link->stats.link_congs++;
return true;
}
/**
* link_prepare_wakeup - prepare users for wakeup after congestion
* @link: congested link
* Move a number of waiting users, as permitted by available space in
* the send queue, from link wait queue to node wait queue for wakeup
*/
static void link_prepare_wakeup(struct tipc_link *link)
{
struct sk_buff_head *wq = &link->waiting_sks;
struct sk_buff *buf;
uint pend_qsz = link->out_queue_size;
for (buf = skb_peek(wq); buf; buf = skb_peek(wq)) {
if (pend_qsz >= link->queue_limit[TIPC_SKB_CB(buf)->chain_imp])
break;
pend_qsz += TIPC_SKB_CB(buf)->chain_sz;
__skb_queue_tail(&link->owner->waiting_sks, __skb_dequeue(wq));
}
}
/**
* 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);
struct tipc_node *owner = l_ptr->owner;
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 (!skb_queue_empty(&l_ptr->waiting_sks)) {
skb_queue_splice_init(&l_ptr->waiting_sks, &owner->waiting_sks);
owner->action_flags |= TIPC_WAKEUP_USERS;
}
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);
}
}
/* tipc_link_cong: determine return value and how to treat the
* sent buffer during link congestion.
* - For plain, errorless user data messages we keep the buffer and
* return -ELINKONG.
* - For all other messages we discard the buffer and return -EHOSTUNREACH
* - For TIPC internal messages we also reset the link
*/
static int tipc_link_cong(struct tipc_link *link, struct sk_buff *buf)
{
struct tipc_msg *msg = buf_msg(buf);
uint imp = tipc_msg_tot_importance(msg);
u32 oport = msg_tot_origport(msg);
if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) {
pr_warn("%s<%s>, send queue full", link_rst_msg, link->name);
tipc_link_reset(link);
goto drop;
}
if (unlikely(msg_errcode(msg)))
goto drop;
if (unlikely(msg_reroute_cnt(msg)))
goto drop;
if (TIPC_SKB_CB(buf)->wakeup_pending)
return -ELINKCONG;
if (link_schedule_user(link, oport, TIPC_SKB_CB(buf)->chain_sz, imp))
return -ELINKCONG;
drop:
kfree_skb_list(buf);
return -EHOSTUNREACH;
}
/**
* __tipc_link_xmit(): same as tipc_link_xmit, but destlink is known & locked
* @link: link to use
* @buf: chain of buffers containing message
* Consumes the buffer chain, except when returning -ELINKCONG
* Returns 0 if success, otherwise errno: -ELINKCONG, -EMSGSIZE (plain socket
* user data messages) or -EHOSTUNREACH (all other messages/senders)
* Only the socket functions tipc_send_stream() and tipc_send_packet() need
* to act on the return value, since they may need to do more send attempts.
*/
int __tipc_link_xmit(struct tipc_link *link, struct sk_buff *buf)
{
struct tipc_msg *msg = buf_msg(buf);
uint psz = msg_size(msg);
uint qsz = link->out_queue_size;
uint sndlim = link->queue_limit[0];
uint imp = tipc_msg_tot_importance(msg);
uint mtu = link->max_pkt;
uint ack = mod(link->next_in_no - 1);
uint seqno = link->next_out_no;
uint bc_last_in = link->owner->bclink.last_in;
struct tipc_media_addr *addr = &link->media_addr;
struct sk_buff *next = buf->next;
/* Match queue limits against msg importance: */
if (unlikely(qsz >= link->queue_limit[imp]))
return tipc_link_cong(link, buf);
/* Has valid packet limit been used ? */
if (unlikely(psz > mtu)) {
kfree_skb_list(buf);
return -EMSGSIZE;
}
/* Prepare each packet for sending, and add to outqueue: */
while (buf) {
next = buf->next;
msg = buf_msg(buf);
msg_set_word(msg, 2, ((ack << 16) | mod(seqno)));
msg_set_bcast_ack(msg, bc_last_in);
if (!link->first_out) {
link->first_out = buf;
} else if (qsz < sndlim) {
link->last_out->next = buf;
} else if (tipc_msg_bundle(link->last_out, buf, mtu)) {
link->stats.sent_bundled++;
buf = next;
next = buf->next;
continue;
} else if (tipc_msg_make_bundle(&buf, mtu, link->addr)) {
link->stats.sent_bundled++;
link->stats.sent_bundles++;
link->last_out->next = buf;
if (!link->next_out)
link->next_out = buf;
} else {
link->last_out->next = buf;
if (!link->next_out)
link->next_out = buf;
}
/* Send packet if possible: */
if (likely(++qsz <= sndlim)) {
tipc_bearer_send(link->bearer_id, buf, addr);
link->next_out = next;
link->unacked_window = 0;
}
seqno++;
link->last_out = buf;
buf = next;
}
link->next_out_no = seqno;
link->out_queue_size = qsz;
return 0;
}
/**
* tipc_link_xmit() is the general link level function for message sending
* @buf: chain of buffers containing message
* @dsz: amount of user data to be sent
* @dnode: address of destination node
* @selector: a number used for deterministic link selection
* Consumes the buffer chain, except when returning -ELINKCONG
* Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE
*/
int tipc_link_xmit(struct sk_buff *buf, u32 dnode, u32 selector)
{
struct tipc_link *link = NULL;
struct tipc_node *node;
int rc = -EHOSTUNREACH;
node = tipc_node_find(dnode);
if (node) {
tipc_node_lock(node);
link = node->active_links[selector & 1];
if (link)
rc = __tipc_link_xmit(link, buf);
tipc_node_unlock(node);
}
if (link)
return rc;
if (likely(in_own_node(dnode)))
return tipc_sk_rcv(buf);
kfree_skb_list(buf);
return rc;
}
/*
* 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 *link)
{
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, link->addr);
msg_set_last_bcast(msg, link->owner->bclink.acked);
__tipc_link_xmit(link, buf);
}
/*
* 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_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, BUNDLE_CLOSED);
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 (released && !skb_queue_empty(&l_ptr->waiting_sks)) {
link_prepare_wakeup(l_ptr);
l_ptr->owner->action_flags |= TIPC_WAKEUP_USERS;
}
/* 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);
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);
}
if (tipc_link_prepare_input(l_ptr, &buf)) {
tipc_node_unlock(n_ptr);
continue;
}
tipc_node_unlock(n_ptr);
msg = buf_msg(buf);
if (tipc_link_input(l_ptr, buf) != 0)
goto discard;
continue;
unlock_discard:
tipc_node_unlock(n_ptr);
discard:
kfree_skb(buf);
}
}
/**
* tipc_link_prepare_input - process TIPC link messages
*
* returns nonzero if the message was consumed
*
* Node lock must be held
*/
static int tipc_link_prepare_input(struct tipc_link *l, struct sk_buff **buf)
{
struct tipc_node *n;
struct tipc_msg *msg;
int res = -EINVAL;
n = l->owner;
msg = buf_msg(*buf);
switch (msg_user(msg)) {
case CHANGEOVER_PROTOCOL:
if (tipc_link_tunnel_rcv(n, buf))
res = 0;
break;
case MSG_FRAGMENTER:
l->stats.recv_fragments++;
if (tipc_buf_append(&l->reasm_buf, buf)) {
l->stats.recv_fragmented++;
res = 0;
} else if (!l->reasm_buf) {
tipc_link_reset(l);
}
break;
case MSG_BUNDLER:
l->stats.recv_bundles++;
l->stats.recv_bundled += msg_msgcnt(msg);
res = 0;
break;
case NAME_DISTRIBUTOR:
n->bclink.recv_permitted = true;
res = 0;
break;
case BCAST_PROTOCOL:
tipc_link_sync_rcv(n, *buf);
break;
default:
res = 0;
}
return res;
}
/**
* tipc_link_input - Deliver message too higher layers
*/
static int tipc_link_input(struct tipc_link *l, struct sk_buff *buf)
{
struct tipc_msg *msg = buf_msg(buf);
int res = 0;
switch (msg_user(msg)) {
case TIPC_LOW_IMPORTANCE:
case TIPC_MEDIUM_IMPORTANCE:
case TIPC_HIGH_IMPORTANCE:
case TIPC_CRITICAL_IMPORTANCE:
case CONN_MANAGER:
tipc_sk_rcv(buf);
break;
case NAME_DISTRIBUTOR:
tipc_named_rcv(buf);
break;
case MSG_BUNDLER:
tipc_link_bundle_rcv(buf);
break;
default:
res = -EINVAL;
}
return res;
}
/**
* 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;
struct tipc_msg *omsg;
while (msgcount--) {
obuf = buf_extract(buf, pos);
if (obuf == NULL) {
pr_warn("Link unable to unbundle message(s)\n");
break;
}
omsg = buf_msg(obuf);
pos += align(msg_size(omsg));
if (msg_isdata(omsg)) {
if (unlikely(msg_type(omsg) == TIPC_MCAST_MSG))
tipc_sk_mcast_rcv(obuf);
else
tipc_sk_rcv(obuf);
} else if (msg_user(omsg) == CONN_MANAGER) {
tipc_sk_rcv(obuf);
} else if (msg_user(omsg) == NAME_DISTRIBUTOR) {
tipc_named_rcv(obuf);
} else {
pr_warn("Illegal bundled msg: %u\n", msg_user(omsg));
kfree_skb(obuf);
}
}
kfree_skb(buf);
}
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");
}