linux/net/tipc/bearer.c
Allan Stephens 1209966cd5 tipc: Add monitoring of number of nodes discovered by bearer
Augments TIPC's discovery object to track the number of neighboring nodes
having an active link to the associated bearer.

This means tipc_disc_update_link_req() becomes either one of:

       tipc_disc_add_dest()
or:
       tipc_disc_remove_dest()

depending on the code flow direction of things.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10 16:04:01 -04:00

677 lines
17 KiB
C

/*
* net/tipc/bearer.c: TIPC bearer code
*
* Copyright (c) 1996-2006, Ericsson AB
* Copyright (c) 2004-2006, 2010-2011, Wind River Systems
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the names of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "core.h"
#include "config.h"
#include "bearer.h"
#include "discover.h"
#define MAX_ADDR_STR 32
static struct media media_list[MAX_MEDIA];
static u32 media_count;
struct tipc_bearer tipc_bearers[MAX_BEARERS];
static void bearer_disable(struct tipc_bearer *b_ptr);
/**
* media_name_valid - validate media name
*
* Returns 1 if media name is valid, otherwise 0.
*/
static int media_name_valid(const char *name)
{
u32 len;
len = strlen(name);
if ((len + 1) > TIPC_MAX_MEDIA_NAME)
return 0;
return strspn(name, tipc_alphabet) == len;
}
/**
* media_find - locates specified media object by name
*/
static struct media *media_find(const char *name)
{
struct media *m_ptr;
u32 i;
for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
if (!strcmp(m_ptr->name, name))
return m_ptr;
}
return NULL;
}
/**
* tipc_register_media - register a media type
*
* Bearers for this media type must be activated separately at a later stage.
*/
int tipc_register_media(u32 media_type,
char *name,
int (*enable)(struct tipc_bearer *),
void (*disable)(struct tipc_bearer *),
int (*send_msg)(struct sk_buff *,
struct tipc_bearer *,
struct tipc_media_addr *),
char *(*addr2str)(struct tipc_media_addr *a,
char *str_buf, int str_size),
struct tipc_media_addr *bcast_addr,
const u32 bearer_priority,
const u32 link_tolerance, /* [ms] */
const u32 send_window_limit)
{
struct media *m_ptr;
u32 media_id;
u32 i;
int res = -EINVAL;
write_lock_bh(&tipc_net_lock);
if (tipc_mode != TIPC_NET_MODE) {
warn("Media <%s> rejected, not in networked mode yet\n", name);
goto exit;
}
if (!media_name_valid(name)) {
warn("Media <%s> rejected, illegal name\n", name);
goto exit;
}
if (!bcast_addr) {
warn("Media <%s> rejected, no broadcast address\n", name);
goto exit;
}
if ((bearer_priority < TIPC_MIN_LINK_PRI) ||
(bearer_priority > TIPC_MAX_LINK_PRI)) {
warn("Media <%s> rejected, illegal priority (%u)\n", name,
bearer_priority);
goto exit;
}
if ((link_tolerance < TIPC_MIN_LINK_TOL) ||
(link_tolerance > TIPC_MAX_LINK_TOL)) {
warn("Media <%s> rejected, illegal tolerance (%u)\n", name,
link_tolerance);
goto exit;
}
media_id = media_count++;
if (media_id >= MAX_MEDIA) {
warn("Media <%s> rejected, media limit reached (%u)\n", name,
MAX_MEDIA);
media_count--;
goto exit;
}
for (i = 0; i < media_id; i++) {
if (media_list[i].type_id == media_type) {
warn("Media <%s> rejected, duplicate type (%u)\n", name,
media_type);
media_count--;
goto exit;
}
if (!strcmp(name, media_list[i].name)) {
warn("Media <%s> rejected, duplicate name\n", name);
media_count--;
goto exit;
}
}
m_ptr = &media_list[media_id];
m_ptr->type_id = media_type;
m_ptr->send_msg = send_msg;
m_ptr->enable_bearer = enable;
m_ptr->disable_bearer = disable;
m_ptr->addr2str = addr2str;
memcpy(&m_ptr->bcast_addr, bcast_addr, sizeof(*bcast_addr));
strcpy(m_ptr->name, name);
m_ptr->priority = bearer_priority;
m_ptr->tolerance = link_tolerance;
m_ptr->window = send_window_limit;
res = 0;
exit:
write_unlock_bh(&tipc_net_lock);
return res;
}
/**
* tipc_media_addr_printf - record media address in print buffer
*/
void tipc_media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a)
{
struct media *m_ptr;
u32 media_type;
u32 i;
media_type = ntohl(a->type);
for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
if (m_ptr->type_id == media_type)
break;
}
if ((i < media_count) && (m_ptr->addr2str != NULL)) {
char addr_str[MAX_ADDR_STR];
tipc_printf(pb, "%s(%s)", m_ptr->name,
m_ptr->addr2str(a, addr_str, sizeof(addr_str)));
} else {
unchar *addr = (unchar *)&a->dev_addr;
tipc_printf(pb, "UNKNOWN(%u)", media_type);
for (i = 0; i < (sizeof(*a) - sizeof(a->type)); i++)
tipc_printf(pb, "-%02x", addr[i]);
}
}
/**
* tipc_media_get_names - record names of registered media in buffer
*/
struct sk_buff *tipc_media_get_names(void)
{
struct sk_buff *buf;
struct media *m_ptr;
int i;
buf = tipc_cfg_reply_alloc(MAX_MEDIA * TLV_SPACE(TIPC_MAX_MEDIA_NAME));
if (!buf)
return NULL;
read_lock_bh(&tipc_net_lock);
for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
tipc_cfg_append_tlv(buf, TIPC_TLV_MEDIA_NAME, m_ptr->name,
strlen(m_ptr->name) + 1);
}
read_unlock_bh(&tipc_net_lock);
return buf;
}
/**
* bearer_name_validate - validate & (optionally) deconstruct bearer name
* @name - ptr to bearer name string
* @name_parts - ptr to area for bearer name components (or NULL if not needed)
*
* Returns 1 if bearer name is valid, otherwise 0.
*/
static int bearer_name_validate(const char *name,
struct bearer_name *name_parts)
{
char name_copy[TIPC_MAX_BEARER_NAME];
char *media_name;
char *if_name;
u32 media_len;
u32 if_len;
/* copy bearer name & ensure length is OK */
name_copy[TIPC_MAX_BEARER_NAME - 1] = 0;
/* need above in case non-Posix strncpy() doesn't pad with nulls */
strncpy(name_copy, name, TIPC_MAX_BEARER_NAME);
if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0)
return 0;
/* ensure all component parts of bearer name are present */
media_name = name_copy;
if_name = strchr(media_name, ':');
if (if_name == NULL)
return 0;
*(if_name++) = 0;
media_len = if_name - media_name;
if_len = strlen(if_name) + 1;
/* validate component parts of bearer name */
if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
(if_len <= 1) || (if_len > TIPC_MAX_IF_NAME) ||
(strspn(media_name, tipc_alphabet) != (media_len - 1)) ||
(strspn(if_name, tipc_alphabet) != (if_len - 1)))
return 0;
/* return bearer name components, if necessary */
if (name_parts) {
strcpy(name_parts->media_name, media_name);
strcpy(name_parts->if_name, if_name);
}
return 1;
}
/**
* bearer_find - locates bearer object with matching bearer name
*/
static struct tipc_bearer *bearer_find(const char *name)
{
struct tipc_bearer *b_ptr;
u32 i;
for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
if (b_ptr->active && (!strcmp(b_ptr->name, name)))
return b_ptr;
}
return NULL;
}
/**
* tipc_bearer_find_interface - locates bearer object with matching interface name
*/
struct tipc_bearer *tipc_bearer_find_interface(const char *if_name)
{
struct tipc_bearer *b_ptr;
char *b_if_name;
u32 i;
for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
if (!b_ptr->active)
continue;
b_if_name = strchr(b_ptr->name, ':') + 1;
if (!strcmp(b_if_name, if_name))
return b_ptr;
}
return NULL;
}
/**
* tipc_bearer_get_names - record names of bearers in buffer
*/
struct sk_buff *tipc_bearer_get_names(void)
{
struct sk_buff *buf;
struct media *m_ptr;
struct tipc_bearer *b_ptr;
int i, j;
buf = tipc_cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME));
if (!buf)
return NULL;
read_lock_bh(&tipc_net_lock);
for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
for (j = 0; j < MAX_BEARERS; j++) {
b_ptr = &tipc_bearers[j];
if (b_ptr->active && (b_ptr->media == m_ptr)) {
tipc_cfg_append_tlv(buf, TIPC_TLV_BEARER_NAME,
b_ptr->name,
strlen(b_ptr->name) + 1);
}
}
}
read_unlock_bh(&tipc_net_lock);
return buf;
}
void tipc_bearer_add_dest(struct tipc_bearer *b_ptr, u32 dest)
{
tipc_nmap_add(&b_ptr->nodes, dest);
tipc_bcbearer_sort();
tipc_disc_add_dest(b_ptr->link_req);
}
void tipc_bearer_remove_dest(struct tipc_bearer *b_ptr, u32 dest)
{
tipc_nmap_remove(&b_ptr->nodes, dest);
tipc_bcbearer_sort();
tipc_disc_remove_dest(b_ptr->link_req);
}
/*
* bearer_push(): Resolve bearer congestion. Force the waiting
* links to push out their unsent packets, one packet per link
* per iteration, until all packets are gone or congestion reoccurs.
* 'tipc_net_lock' is read_locked when this function is called
* bearer.lock must be taken before calling
* Returns binary true(1) ore false(0)
*/
static int bearer_push(struct tipc_bearer *b_ptr)
{
u32 res = 0;
struct link *ln, *tln;
if (b_ptr->blocked)
return 0;
while (!list_empty(&b_ptr->cong_links) && (res != PUSH_FAILED)) {
list_for_each_entry_safe(ln, tln, &b_ptr->cong_links, link_list) {
res = tipc_link_push_packet(ln);
if (res == PUSH_FAILED)
break;
if (res == PUSH_FINISHED)
list_move_tail(&ln->link_list, &b_ptr->links);
}
}
return list_empty(&b_ptr->cong_links);
}
void tipc_bearer_lock_push(struct tipc_bearer *b_ptr)
{
int res;
spin_lock_bh(&b_ptr->lock);
res = bearer_push(b_ptr);
spin_unlock_bh(&b_ptr->lock);
if (res)
tipc_bcbearer_push();
}
/*
* Interrupt enabling new requests after bearer congestion or blocking:
* See bearer_send().
*/
void tipc_continue(struct tipc_bearer *b_ptr)
{
spin_lock_bh(&b_ptr->lock);
b_ptr->continue_count++;
if (!list_empty(&b_ptr->cong_links))
tipc_k_signal((Handler)tipc_bearer_lock_push, (unsigned long)b_ptr);
b_ptr->blocked = 0;
spin_unlock_bh(&b_ptr->lock);
}
/*
* Schedule link for sending of messages after the bearer
* has been deblocked by 'continue()'. This method is called
* when somebody tries to send a message via this link while
* the bearer is congested. 'tipc_net_lock' is in read_lock here
* bearer.lock is busy
*/
static void tipc_bearer_schedule_unlocked(struct tipc_bearer *b_ptr, struct link *l_ptr)
{
list_move_tail(&l_ptr->link_list, &b_ptr->cong_links);
}
/*
* Schedule link for sending of messages after the bearer
* has been deblocked by 'continue()'. This method is called
* when somebody tries to send a message via this link while
* the bearer is congested. 'tipc_net_lock' is in read_lock here,
* bearer.lock is free
*/
void tipc_bearer_schedule(struct tipc_bearer *b_ptr, struct link *l_ptr)
{
spin_lock_bh(&b_ptr->lock);
tipc_bearer_schedule_unlocked(b_ptr, l_ptr);
spin_unlock_bh(&b_ptr->lock);
}
/*
* tipc_bearer_resolve_congestion(): Check if there is bearer congestion,
* and if there is, try to resolve it before returning.
* 'tipc_net_lock' is read_locked when this function is called
*/
int tipc_bearer_resolve_congestion(struct tipc_bearer *b_ptr, struct link *l_ptr)
{
int res = 1;
if (list_empty(&b_ptr->cong_links))
return 1;
spin_lock_bh(&b_ptr->lock);
if (!bearer_push(b_ptr)) {
tipc_bearer_schedule_unlocked(b_ptr, l_ptr);
res = 0;
}
spin_unlock_bh(&b_ptr->lock);
return res;
}
/**
* tipc_bearer_congested - determines if bearer is currently congested
*/
int tipc_bearer_congested(struct tipc_bearer *b_ptr, struct link *l_ptr)
{
if (unlikely(b_ptr->blocked))
return 1;
if (likely(list_empty(&b_ptr->cong_links)))
return 0;
return !tipc_bearer_resolve_congestion(b_ptr, l_ptr);
}
/**
* tipc_enable_bearer - enable bearer with the given name
*/
int tipc_enable_bearer(const char *name, u32 disc_domain, u32 priority)
{
struct tipc_bearer *b_ptr;
struct media *m_ptr;
struct bearer_name b_name;
char addr_string[16];
u32 bearer_id;
u32 with_this_prio;
u32 i;
int res = -EINVAL;
if (tipc_mode != TIPC_NET_MODE) {
warn("Bearer <%s> rejected, not supported in standalone mode\n",
name);
return -ENOPROTOOPT;
}
if (!bearer_name_validate(name, &b_name)) {
warn("Bearer <%s> rejected, illegal name\n", name);
return -EINVAL;
}
if (tipc_addr_domain_valid(disc_domain) &&
(disc_domain != tipc_own_addr)) {
if (tipc_in_scope(disc_domain, tipc_own_addr)) {
disc_domain = tipc_own_addr & TIPC_CLUSTER_MASK;
res = 0; /* accept any node in own cluster */
} else if (in_own_cluster(disc_domain))
res = 0; /* accept specified node in own cluster */
}
if (res) {
warn("Bearer <%s> rejected, illegal discovery domain\n", name);
return -EINVAL;
}
if ((priority < TIPC_MIN_LINK_PRI ||
priority > TIPC_MAX_LINK_PRI) &&
(priority != TIPC_MEDIA_LINK_PRI)) {
warn("Bearer <%s> rejected, illegal priority\n", name);
return -EINVAL;
}
write_lock_bh(&tipc_net_lock);
m_ptr = media_find(b_name.media_name);
if (!m_ptr) {
warn("Bearer <%s> rejected, media <%s> not registered\n", name,
b_name.media_name);
goto exit;
}
if (priority == TIPC_MEDIA_LINK_PRI)
priority = m_ptr->priority;
restart:
bearer_id = MAX_BEARERS;
with_this_prio = 1;
for (i = MAX_BEARERS; i-- != 0; ) {
if (!tipc_bearers[i].active) {
bearer_id = i;
continue;
}
if (!strcmp(name, tipc_bearers[i].name)) {
warn("Bearer <%s> rejected, already enabled\n", name);
goto exit;
}
if ((tipc_bearers[i].priority == priority) &&
(++with_this_prio > 2)) {
if (priority-- == 0) {
warn("Bearer <%s> rejected, duplicate priority\n",
name);
goto exit;
}
warn("Bearer <%s> priority adjustment required %u->%u\n",
name, priority + 1, priority);
goto restart;
}
}
if (bearer_id >= MAX_BEARERS) {
warn("Bearer <%s> rejected, bearer limit reached (%u)\n",
name, MAX_BEARERS);
goto exit;
}
b_ptr = &tipc_bearers[bearer_id];
strcpy(b_ptr->name, name);
res = m_ptr->enable_bearer(b_ptr);
if (res) {
warn("Bearer <%s> rejected, enable failure (%d)\n", name, -res);
goto exit;
}
b_ptr->identity = bearer_id;
b_ptr->media = m_ptr;
b_ptr->net_plane = bearer_id + 'A';
b_ptr->active = 1;
b_ptr->priority = priority;
INIT_LIST_HEAD(&b_ptr->cong_links);
INIT_LIST_HEAD(&b_ptr->links);
spin_lock_init(&b_ptr->lock);
res = tipc_disc_create(b_ptr, &m_ptr->bcast_addr, disc_domain);
if (res) {
bearer_disable(b_ptr);
warn("Bearer <%s> rejected, discovery object creation failed\n",
name);
goto exit;
}
info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
name, tipc_addr_string_fill(addr_string, disc_domain), priority);
exit:
write_unlock_bh(&tipc_net_lock);
return res;
}
/**
* tipc_block_bearer(): Block the bearer with the given name,
* and reset all its links
*/
int tipc_block_bearer(const char *name)
{
struct tipc_bearer *b_ptr = NULL;
struct link *l_ptr;
struct link *temp_l_ptr;
read_lock_bh(&tipc_net_lock);
b_ptr = bearer_find(name);
if (!b_ptr) {
warn("Attempt to block unknown bearer <%s>\n", name);
read_unlock_bh(&tipc_net_lock);
return -EINVAL;
}
info("Blocking bearer <%s>\n", name);
spin_lock_bh(&b_ptr->lock);
b_ptr->blocked = 1;
list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
struct tipc_node *n_ptr = l_ptr->owner;
spin_lock_bh(&n_ptr->lock);
tipc_link_reset(l_ptr);
spin_unlock_bh(&n_ptr->lock);
}
spin_unlock_bh(&b_ptr->lock);
read_unlock_bh(&tipc_net_lock);
return 0;
}
/**
* bearer_disable -
*
* Note: This routine assumes caller holds tipc_net_lock.
*/
static void bearer_disable(struct tipc_bearer *b_ptr)
{
struct link *l_ptr;
struct link *temp_l_ptr;
info("Disabling bearer <%s>\n", b_ptr->name);
spin_lock_bh(&b_ptr->lock);
b_ptr->blocked = 1;
b_ptr->media->disable_bearer(b_ptr);
list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
tipc_link_delete(l_ptr);
}
if (b_ptr->link_req)
tipc_disc_delete(b_ptr->link_req);
spin_unlock_bh(&b_ptr->lock);
memset(b_ptr, 0, sizeof(struct tipc_bearer));
}
int tipc_disable_bearer(const char *name)
{
struct tipc_bearer *b_ptr;
int res;
write_lock_bh(&tipc_net_lock);
b_ptr = bearer_find(name);
if (b_ptr == NULL) {
warn("Attempt to disable unknown bearer <%s>\n", name);
res = -EINVAL;
} else {
bearer_disable(b_ptr);
res = 0;
}
write_unlock_bh(&tipc_net_lock);
return res;
}
void tipc_bearer_stop(void)
{
u32 i;
for (i = 0; i < MAX_BEARERS; i++) {
if (tipc_bearers[i].active)
bearer_disable(&tipc_bearers[i]);
}
media_count = 0;
}