- 根目录:
- net
- batman-adv
- vis.c
/*
* Copyright (C) 2008-2011 B.A.T.M.A.N. contributors:
*
* Simon Wunderlich
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA
*
*/
#include "main.h"
#include "send.h"
#include "translation-table.h"
#include "vis.h"
#include "soft-interface.h"
#include "hard-interface.h"
#include "hash.h"
#include "originator.h"
#define MAX_VIS_PACKET_SIZE 1000
/* Returns the smallest signed integer in two's complement with the sizeof x */
#define smallest_signed_int(x) (1u << (7u + 8u * (sizeof(x) - 1u)))
/* Checks if a sequence number x is a predecessor/successor of y.
* they handle overflows/underflows and can correctly check for a
* predecessor/successor unless the variable sequence number has grown by
* more then 2**(bitwidth(x)-1)-1.
* This means that for a uint8_t with the maximum value 255, it would think:
* - when adding nothing - it is neither a predecessor nor a successor
* - before adding more than 127 to the starting value - it is a predecessor,
* - when adding 128 - it is neither a predecessor nor a successor,
* - after adding more than 127 to the starting value - it is a successor */
#define seq_before(x, y) ({typeof(x) _dummy = (x - y); \
_dummy > smallest_signed_int(_dummy); })
#define seq_after(x, y) seq_before(y, x)
static void start_vis_timer(struct bat_priv *bat_priv);
/* free the info */
static void free_info(struct kref *ref)
{
struct vis_info *info = container_of(ref, struct vis_info, refcount);
struct bat_priv *bat_priv = info->bat_priv;
struct recvlist_node *entry, *tmp;
list_del_init(&info->send_list);
spin_lock_bh(&bat_priv->vis_list_lock);
list_for_each_entry_safe(entry, tmp, &info->recv_list, list) {
list_del(&entry->list);
kfree(entry);
}
spin_unlock_bh(&bat_priv->vis_list_lock);
kfree_skb(info->skb_packet);
kfree(info);
}
/* Compare two vis packets, used by the hashing algorithm */
static int vis_info_cmp(struct hlist_node *node, void *data2)
{
struct vis_info *d1, *d2;
struct vis_packet *p1, *p2;
d1 = container_of(node, struct vis_info, hash_entry);
d2 = data2;
p1 = (struct vis_packet *)d1->skb_packet->data;
p2 = (struct vis_packet *)d2->skb_packet->data;
return compare_eth(p1->vis_orig, p2->vis_orig);
}
/* hash function to choose an entry in a hash table of given size */
/* hash algorithm from http://en.wikipedia.org/wiki/Hash_table */
static int vis_info_choose(void *data, int size)
{
struct vis_info *vis_info = data;
struct vis_packet *packet;
unsigned char *key;
uint32_t hash = 0;
size_t i;
packet = (struct vis_packet *)vis_info->skb_packet->data;
key = packet->vis_orig;
for (i = 0; i < ETH_ALEN; i++) {
hash += key[i];
hash += (hash << 10);
hash ^= (hash >> 6);
}
hash += (hash << 3);
hash ^= (hash >> 11);
hash += (hash << 15);
return hash % size;
}
static struct vis_info *vis_hash_find(struct bat_priv *bat_priv,
void *data)
{
struct hashtable_t *hash = bat_priv->vis_hash;
struct hlist_head *head;
struct hlist_node *node;
struct vis_info *vis_info, *vis_info_tmp = NULL;
int index;
if (!hash)
return NULL;
index = vis_info_choose(data, hash->size);
head = &hash->table[index];
rcu_read_lock();
hlist_for_each_entry_rcu(vis_info, node, head, hash_entry) {
if (!vis_info_cmp(node, data))
continue;
vis_info_tmp = vis_info;
break;
}
rcu_read_unlock();
return vis_info_tmp;
}
/* insert interface to the list of interfaces of one originator, if it
* does not already exist in the list */
static void vis_data_insert_interface(const uint8_t *interface,
struct hlist_head *if_list,
bool primary)
{
struct if_list_entry *entry;
struct hlist_node *pos;
hlist_for_each_entry(entry, pos, if_list, list) {
if (compare_eth(entry->addr, (void *)interface))
return;
}
/* its a new address, add it to the list */
entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
if (!entry)
return;
memcpy(entry->addr, interface, ETH_ALEN);
entry->primary = primary;
hlist_add_head(&entry->list, if_list);
}
static ssize_t vis_data_read_prim_sec(char *buff, struct hlist_head *if_list)
{
struct if_list_entry *entry;
struct hlist_node *pos;
size_t len = 0;
hlist_for_each_entry(entry, pos, if_list, list) {
if (entry->primary)
len += sprintf(buff + len, "PRIMARY, ");
else
len += sprintf(buff + len, "SEC %pM, ", entry->addr);
}
return len;
}
static size_t vis_data_count_prim_sec(struct hlist_head *if_list)
{
struct if_list_entry *entry;
struct hlist_node *pos;
size_t count = 0;
hlist_for_each_entry(entry, pos, if_list, list) {
if (entry->primary)
count += 9;
else
count += 23;
}
return count;
}
/* read an entry */
static ssize_t vis_data_read_entry(char *buff, struct vis_info_entry *entry,
uint8_t *src, bool primary)
{
/* maximal length: max(4+17+2, 3+17+1+3+2) == 26 */
if (primary && entry->quality == 0)
return sprintf(buff, "HNA %pM, ", entry->dest);
else if (compare_eth(entry->src, src))
return sprintf(buff, "TQ %pM %d, ", entry->dest,
entry->quality);
return 0;
}
int vis_seq_print_text(struct seq_file *seq, void *offset)
{
struct hlist_node *node;
struct hlist_head *head;
struct vis_info *info;
struct vis_packet *packet;
struct vis_info_entry *entries;
struct net_device *net_dev = (struct net_device *)seq->private;
struct bat_priv *bat_priv = netdev_priv(net_dev);
struct hashtable_t *hash = bat_priv->vis_hash;
HLIST_HEAD(vis_if_list);
struct if_list_entry *entry;
struct hlist_node *pos, *n;
int i, j;
int vis_server = atomic_read(&bat_priv->vis_mode);
size_t buff_pos, buf_size;
char *buff;
int compare;
if ((!bat_priv->primary_if) ||
(vis_server == VIS_TYPE_CLIENT_UPDATE))
return 0;
buf_size = 1;
/* Estimate length */
spin_lock_bh(&bat_priv->vis_hash_lock);
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
rcu_read_lock();
hlist_for_each_entry_rcu(info, node, head, hash_entry) {
packet = (struct vis_packet *)info->skb_packet->data;
entries = (struct vis_info_entry *)
((char *)packet + sizeof(struct vis_packet));
for (j = 0; j < packet->entries; j++) {
if (entries[j].quality == 0)
continue;
compare =
compare_eth(entries[j].src, packet->vis_orig);
vis_data_insert_interface(entries[j].src,
&vis_if_list,
compare);
}
hlist_for_each_entry(entry, pos, &vis_if_list, list) {
buf_size += 18 + 26 * packet->entries;
/* add primary/secondary records */
if (compare_eth(entry->addr, packet->vis_orig))
buf_size +=
vis_data_count_prim_sec(&vis_if_list);
buf_size += 1;
}
hlist_for_each_entry_safe(entry, pos, n, &vis_if_list,
list) {
hlist_del(&entry->list);
kfree(entry);
}
}
rcu_read_unlock();
}
buff = kmalloc(buf_size, GFP_ATOMIC);
if (!buff) {
spin_unlock_bh(&bat_priv->vis_hash_lock);
return -ENOMEM;
}
buff[0] = '\0';
buff_pos = 0;
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
rcu_read_lock();
hlist_for_each_entry_rcu(info, node, head, hash_entry) {
packet = (struct vis_packet *)info->skb_packet->data;
entries = (struct vis_info_entry *)
((char *)packet + sizeof(struct vis_packet));
for (j = 0; j < packet->entries; j++) {
if (entries[j].quality == 0)
continue;
compare =
compare_eth(entries[j].src, packet->vis_orig);
vis_data_insert_interface(entries[j].src,
&vis_if_list,
compare);
}
hlist_for_each_entry(entry, pos, &vis_if_list, list) {
buff_pos += sprintf(buff + buff_pos, "%pM,",
entry->addr);
for (j = 0; j < packet->entries; j++)
buff_pos += vis_data_read_entry(
buff + buff_pos,
&entries[j],
entry->addr,
entry->primary);
/* add primary/secondary records */
if (compare_eth(entry->addr, packet->vis_orig))
buff_pos +=
vis_data_read_prim_sec(buff + buff_pos,
&vis_if_list);
buff_pos += sprintf(buff + buff_pos, "\n");
}
hlist_for_each_entry_safe(entry, pos, n, &vis_if_list,
list) {
hlist_del(&entry->list);
kfree(entry);
}
}
rcu_read_unlock();
}
spin_unlock_bh(&bat_priv->vis_hash_lock);
seq_printf(seq, "%s", buff);
kfree(buff);
return 0;
}
/* add the info packet to the send list, if it was not
* already linked in. */
static void send_list_add(struct bat_priv *bat_priv, struct vis_info *info)
{
if (list_empty(&info->send_list)) {
kref_get(&info->refcount);
list_add_tail(&info->send_list, &bat_priv->vis_send_list);
}
}
/* delete the info packet from the send list, if it was
* linked in. */
static void send_list_del(struct vis_info *info)
{
if (!list_empty(&info->send_list)) {
list_del_init(&info->send_list);
kref_put(&info->refcount, free_info);
}
}
/* tries to add one entry to the receive list. */
static void recv_list_add(struct bat_priv *bat_priv,
struct list_head *recv_list, char *mac)
{
struct recvlist_node *entry;
entry = kmalloc(sizeof(struct recvlist_node), GFP_ATOMIC);
if (!entry)
return;
memcpy(entry->mac, mac, ETH_ALEN);
spin_lock_bh(&bat_priv->vis_list_lock);
list_add_tail(&entry->list, recv_list);
spin_unlock_bh(&bat_priv->vis_list_lock);
}
/* returns 1 if this mac is in the recv_list */
static int recv_list_is_in(struct bat_priv *bat_priv,
struct list_head *recv_list, char *mac)
{
struct recvlist_node *entry;
spin_lock_bh(&bat_priv->vis_list_lock);
list_for_each_entry(entry, recv_list, list) {
if (compare_eth(entry->mac, mac)) {
spin_unlock_bh(&bat_priv->vis_list_lock);
return 1;
}
}
spin_unlock_bh(&bat_priv->vis_list_lock);
return 0;
}
/* try to add the packet to the vis_hash. return NULL if invalid (e.g. too old,
* broken.. ). vis hash must be locked outside. is_new is set when the packet
* is newer than old entries in the hash. */
static struct vis_info *add_packet(struct bat_priv *bat_priv,
struct vis_packet *vis_packet,
int vis_info_len, int *is_new,
int make_broadcast)
{
struct vis_info *info, *old_info;
struct vis_packet *search_packet, *old_packet;
struct vis_info search_elem;
struct vis_packet *packet;
int hash_added;
*is_new = 0;
/* sanity check */
if (!bat_priv->vis_hash)
return NULL;
/* see if the packet is already in vis_hash */
search_elem.skb_packet = dev_alloc_skb(sizeof(struct vis_packet));
if (!search_elem.skb_packet)
return NULL;
search_packet = (struct vis_packet *)skb_put(search_elem.skb_packet,
sizeof(struct vis_packet));
memcpy(search_packet->vis_orig, vis_packet->vis_orig, ETH_ALEN);
old_info = vis_hash_find(bat_priv, &search_elem);
kfree_skb(search_elem.skb_packet);
if (old_info) {
old_packet = (struct vis_packet *)old_info->skb_packet->data;
if (!seq_after(ntohl(vis_packet->seqno),
ntohl(old_packet->seqno))) {
if (old_packet->seqno == vis_packet->seqno) {
recv_list_add(bat_priv, &old_info->recv_list,
vis_packet->sender_orig);
return old_info;
} else {
/* newer packet is already in hash. */
return NULL;
}
}
/* remove old entry */
hash_remove(bat_priv->vis_hash, vis_info_cmp, vis_info_choose,
old_info);
send_list_del(old_info);
kref_put(&old_info->refcount, free_info);
}
info = kmalloc(sizeof(struct vis_info), GFP_ATOMIC);
if (!info)
return NULL;
info->skb_packet = dev_alloc_skb(sizeof(struct vis_packet) +
vis_info_len + sizeof(struct ethhdr));
if (!info->skb_packet) {
kfree(info);
return NULL;
}
skb_reserve(info->skb_packet, sizeof(struct ethhdr));
packet = (struct vis_packet *)skb_put(info->skb_packet,
sizeof(struct vis_packet) +
vis_info_len);
kref_init(&info->refcount);
INIT_LIST_HEAD(&info->send_list);
INIT_LIST_HEAD(&info->recv_list);
info->first_seen = jiffies;
info->bat_priv = bat_priv;
memcpy(packet, vis_packet, sizeof(struct vis_packet) + vis_info_len);
/* initialize and add new packet. */
*is_new = 1;
/* Make it a broadcast packet, if required */
if (make_broadcast)
memcpy(packet->target_orig, broadcast_addr, ETH_ALEN);
/* repair if entries is longer than packet. */
if (packet->entries * sizeof(struct vis_info_entry) > vis_info_len)
packet->entries = vis_info_len / sizeof(struct vis_info_entry);
recv_list_add(bat_priv, &info->recv_list, packet->sender_orig);
/* try to add it */
hash_added = hash_add(bat_priv->vis_hash, vis_info_cmp, vis_info_choose,
info, &info->hash_entry);
if (hash_added < 0) {
/* did not work (for some reason) */
kref_put(&info->refcount, free_info);
info = NULL;
}
return info;
}
/* handle the server sync packet, forward if needed. */
void receive_server_sync_packet(struct bat_priv *bat_priv,
struct vis_packet *vis_packet,
int vis_info_len)
{
struct vis_info *info;
int is_new, make_broadcast;
int vis_server = atomic_read(&bat_priv->vis_mode);
make_broadcast = (vis_server == VIS_TYPE_SERVER_SYNC);
spin_lock_bh(&bat_priv->vis_hash_lock);
info = add_packet(bat_priv, vis_packet, vis_info_len,
&is_new, make_broadcast);
if (!info)
goto end;
/* only if we are server ourselves and packet is newer than the one in
* hash.*/
if (vis_server == VIS_TYPE_SERVER_SYNC && is_new)
send_list_add(bat_priv, info);
end:
spin_unlock_bh(&bat_priv->vis_hash_lock);
}
/* handle an incoming client update packet and schedule forward if needed. */
void receive_client_update_packet(struct bat_priv *bat_priv,
struct vis_packet *vis_packet,
int vis_info_len)
{
struct vis_info *info;
struct vis_packet *packet;
int is_new;
int vis_server = atomic_read(&bat_priv->vis_mode);
int are_target = 0;
/* clients shall not broadcast. */
if (is_broadcast_ether_addr(vis_packet->target_orig))
return;
/* Are we the target for this VIS packet? */
if (vis_server == VIS_TYPE_SERVER_SYNC &&
is_my_mac(vis_packet->target_orig))
are_target = 1;
spin_lock_bh(&bat_priv->vis_hash_lock);
info = add_packet(bat_priv, vis_packet, vis_info_len,
&is_new, are_target);
if (!info)
goto end;
/* note that outdated packets will be dropped at this point. */
packet = (struct vis_packet *)info->skb_packet->data;
/* send only if we're the target server or ... */
if (are_target && is_new) {
packet->vis_type = VIS_TYPE_SERVER_SYNC; /* upgrade! */
send_list_add(bat_priv, info);
/* ... we're not the recipient (and thus need to forward). */
} else if (!is_my_mac(packet->target_orig)) {
send_list_add(bat_priv, info);
}
end:
spin_unlock_bh(&bat_priv->vis_hash_lock);
}
/* Walk the originators and find the VIS server with the best tq. Set the packet
* address to its address and return the best_tq.
*
* Must be called with the originator hash locked */
static int find_best_vis_server(struct bat_priv *bat_priv,
struct vis_info *info)
{
struct hashtable_t *hash = bat_priv->orig_hash;
struct hlist_node *node;
struct hlist_head *head;
struct orig_node *orig_node;
struct vis_packet *packet;
int best_tq = -1, i;
packet = (struct vis_packet *)info->skb_packet->data;
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
rcu_read_lock();
hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
if ((orig_node) && (orig_node->router) &&
(orig_node->flags & VIS_SERVER) &&
(orig_node->router->tq_avg > best_tq)) {
best_tq = orig_node->router->tq_avg;
memcpy(packet->target_orig, orig_node->orig,
ETH_ALEN);
}
}
rcu_read_unlock();
}
return best_tq;
}
/* Return true if the vis packet is full. */
static bool vis_packet_full(struct vis_info *info)
{
struct vis_packet *packet;
packet = (struct vis_packet *)info->skb_packet->data;
if (MAX_VIS_PACKET_SIZE / sizeof(struct vis_info_entry)
< packet->entries + 1)
return true;
return false;
}
/* generates a packet of own vis data,
* returns 0 on success, -1 if no packet could be generated */
static int generate_vis_packet(struct bat_priv *bat_priv)
{
struct hashtable_t *hash = bat_priv->orig_hash;
struct hlist_node *node;
struct hlist_head *head;
struct orig_node *orig_node;
struct neigh_node *neigh_node;
struct vis_info *info = (struct vis_info *)bat_priv->my_vis_info;
struct vis_packet *packet = (struct vis_packet *)info->skb_packet->data;
struct vis_info_entry *entry;
struct hna_local_entry *hna_local_entry;
int best_tq = -1, i;
info->first_seen = jiffies;
packet->vis_type = atomic_read(&bat_priv->vis_mode);
memcpy(packet->target_orig, broadcast_addr, ETH_ALEN);
packet->ttl = TTL;
packet->seqno = htonl(ntohl(packet->seqno) + 1);
packet->entries = 0;
skb_trim(info->skb_packet, sizeof(struct vis_packet));
if (packet->vis_type == VIS_TYPE_CLIENT_UPDATE) {
best_tq = find_best_vis_server(bat_priv, info);
if (best_tq < 0)
return -1;
}
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
rcu_read_lock();
hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
neigh_node = orig_node->router;
if (!neigh_node)
continue;
if (!compare_eth(neigh_node->addr, orig_node->orig))
continue;
if (neigh_node->if_incoming->if_status != IF_ACTIVE)
continue;
if (neigh_node->tq_avg < 1)
continue;
/* fill one entry into buffer. */
entry = (struct vis_info_entry *)
skb_put(info->skb_packet, sizeof(*entry));
memcpy(entry->src,
neigh_node->if_incoming->net_dev->dev_addr,
ETH_ALEN);
memcpy(entry->dest, orig_node->orig, ETH_ALEN);
entry->quality = neigh_node->tq_avg;
packet->entries++;
if (vis_packet_full(info))
goto unlock;
}
rcu_read_unlock();
}
hash = bat_priv->hna_local_hash;
spin_lock_bh(&bat_priv->hna_lhash_lock);
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
hlist_for_each_entry(hna_local_entry, node, head, hash_entry) {
entry = (struct vis_info_entry *)
skb_put(info->skb_packet,
sizeof(*entry));
memset(entry->src, 0, ETH_ALEN);
memcpy(entry->dest, hna_local_entry->addr, ETH_ALEN);
entry->quality = 0; /* 0 means HNA */
packet->entries++;
if (vis_packet_full(info)) {
spin_unlock_bh(&bat_priv->hna_lhash_lock);
return 0;
}
}
}
spin_unlock_bh(&bat_priv->hna_lhash_lock);
return 0;
unlock:
rcu_read_unlock();
return 0;
}
/* free old vis packets. Must be called with this vis_hash_lock
* held */
static void purge_vis_packets(struct bat_priv *bat_priv)
{
int i;
struct hashtable_t *hash = bat_priv->vis_hash;
struct hlist_node *node, *node_tmp;
struct hlist_head *head;
struct vis_info *info;
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
hlist_for_each_entry_safe(info, node, node_tmp,
head, hash_entry) {
/* never purge own data. */
if (info == bat_priv->my_vis_info)
continue;
if (time_after(jiffies,
info->first_seen + VIS_TIMEOUT * HZ)) {
hlist_del(node);
send_list_del(info);
kref_put(&info->refcount, free_info);
}
}
}
}
static void broadcast_vis_packet(struct bat_priv *bat_priv,
struct vis_info *info)
{
struct hashtable_t *hash = bat_priv->orig_hash;
struct hlist_node *node;
struct hlist_head *head;
struct orig_node *orig_node;
struct vis_packet *packet;
struct sk_buff *skb;
struct hard_iface *hard_iface;
uint8_t dstaddr[ETH_ALEN];
int i;
packet = (struct vis_packet *)info->skb_packet->data;
/* send to all routers in range. */
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
rcu_read_lock();
hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
/* if it's a vis server and reachable, send it. */
if ((!orig_node) || (!orig_node->router))
continue;
if (!(orig_node->flags & VIS_SERVER))
continue;
/* don't send it if we already received the packet from
* this node. */
if (recv_list_is_in(bat_priv, &info->recv_list,
orig_node->orig))
continue;
memcpy(packet->target_orig, orig_node->orig, ETH_ALEN);
hard_iface = orig_node->router->if_incoming;
memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
skb = skb_clone(info->skb_packet, GFP_ATOMIC);
if (skb)
send_skb_packet(skb, hard_iface, dstaddr);
}
rcu_read_unlock();
}
}
static void unicast_vis_packet(struct bat_priv *bat_priv,
struct vis_info *info)
{
struct orig_node *orig_node;
struct neigh_node *neigh_node = NULL;
struct sk_buff *skb;
struct vis_packet *packet;
packet = (struct vis_packet *)info->skb_packet->data;
rcu_read_lock();
orig_node = orig_hash_find(bat_priv, packet->target_orig);
if (!orig_node)
goto unlock;
neigh_node = orig_node->router;
if (!neigh_node)
goto unlock;
if (!atomic_inc_not_zero(&neigh_node->refcount)) {
neigh_node = NULL;
goto unlock;
}
rcu_read_unlock();
skb = skb_clone(info->skb_packet, GFP_ATOMIC);
if (skb)
send_skb_packet(skb, neigh_node->if_incoming,
neigh_node->addr);
goto out;
unlock:
rcu_read_unlock();
out:
if (neigh_node)
neigh_node_free_ref(neigh_node);
if (orig_node)
orig_node_free_ref(orig_node);
return;
}
/* only send one vis packet. called from send_vis_packets() */
static void send_vis_packet(struct bat_priv *bat_priv, struct vis_info *info)
{
struct vis_packet *packet;
packet = (struct vis_packet *)info->skb_packet->data;
if (packet->ttl < 2) {
pr_debug("Error - can't send vis packet: ttl exceeded\n");
return;
}
memcpy(packet->sender_orig, bat_priv->primary_if->net_dev->dev_addr,
ETH_ALEN);
packet->ttl--;
if (is_broadcast_ether_addr(packet->target_orig))
broadcast_vis_packet(bat_priv, info);
else
unicast_vis_packet(bat_priv, info);
packet->ttl++; /* restore TTL */
}
/* called from timer; send (and maybe generate) vis packet. */
static void send_vis_packets(struct work_struct *work)
{
struct delayed_work *delayed_work =
container_of(work, struct delayed_work, work);
struct bat_priv *bat_priv =
container_of(delayed_work, struct bat_priv, vis_work);
struct vis_info *info;
spin_lock_bh(&bat_priv->vis_hash_lock);
purge_vis_packets(bat_priv);
if (generate_vis_packet(bat_priv) == 0) {
/* schedule if generation was successful */
send_list_add(bat_priv, bat_priv->my_vis_info);
}
while (!list_empty(&bat_priv->vis_send_list)) {
info = list_first_entry(&bat_priv->vis_send_list,
typeof(*info), send_list);
kref_get(&info->refcount);
spin_unlock_bh(&bat_priv->vis_hash_lock);
if (bat_priv->primary_if)
send_vis_packet(bat_priv, info);
spin_lock_bh(&bat_priv->vis_hash_lock);
send_list_del(info);
kref_put(&info->refcount, free_info);
}
spin_unlock_bh(&bat_priv->vis_hash_lock);
start_vis_timer(bat_priv);
}
/* init the vis server. this may only be called when if_list is already
* initialized (e.g. bat0 is initialized, interfaces have been added) */
int vis_init(struct bat_priv *bat_priv)
{
struct vis_packet *packet;
int hash_added;
if (bat_priv->vis_hash)
return 1;
spin_lock_bh(&bat_priv->vis_hash_lock);
bat_priv->vis_hash = hash_new(256);
if (!bat_priv->vis_hash) {
pr_err("Can't initialize vis_hash\n");
goto err;
}
bat_priv->my_vis_info = kmalloc(MAX_VIS_PACKET_SIZE, GFP_ATOMIC);
if (!bat_priv->my_vis_info) {
pr_err("Can't initialize vis packet\n");
goto err;
}
bat_priv->my_vis_info->skb_packet = dev_alloc_skb(
sizeof(struct vis_packet) +
MAX_VIS_PACKET_SIZE +
sizeof(struct ethhdr));
if (!bat_priv->my_vis_info->skb_packet)
goto free_info;
skb_reserve(bat_priv->my_vis_info->skb_packet, sizeof(struct ethhdr));
packet = (struct vis_packet *)skb_put(
bat_priv->my_vis_info->skb_packet,
sizeof(struct vis_packet));
/* prefill the vis info */
bat_priv->my_vis_info->first_seen = jiffies -
msecs_to_jiffies(VIS_INTERVAL);
INIT_LIST_HEAD(&bat_priv->my_vis_info->recv_list);
INIT_LIST_HEAD(&bat_priv->my_vis_info->send_list);
kref_init(&bat_priv->my_vis_info->refcount);
bat_priv->my_vis_info->bat_priv = bat_priv;
packet->version = COMPAT_VERSION;
packet->packet_type = BAT_VIS;
packet->ttl = TTL;
packet->seqno = 0;
packet->entries = 0;
INIT_LIST_HEAD(&bat_priv->vis_send_list);
hash_added = hash_add(bat_priv->vis_hash, vis_info_cmp, vis_info_choose,
bat_priv->my_vis_info,
&bat_priv->my_vis_info->hash_entry);
if (hash_added < 0) {
pr_err("Can't add own vis packet into hash\n");
/* not in hash, need to remove it manually. */
kref_put(&bat_priv->my_vis_info->refcount, free_info);
goto err;
}
spin_unlock_bh(&bat_priv->vis_hash_lock);
start_vis_timer(bat_priv);
return 1;
free_info:
kfree(bat_priv->my_vis_info);
bat_priv->my_vis_info = NULL;
err:
spin_unlock_bh(&bat_priv->vis_hash_lock);
vis_quit(bat_priv);
return 0;
}
/* Decrease the reference count on a hash item info */
static void free_info_ref(struct hlist_node *node, void *arg)
{
struct vis_info *info;
info = container_of(node, struct vis_info, hash_entry);
send_list_del(info);
kref_put(&info->refcount, free_info);
}
/* shutdown vis-server */
void vis_quit(struct bat_priv *bat_priv)
{
if (!bat_priv->vis_hash)
return;
cancel_delayed_work_sync(&bat_priv->vis_work);
spin_lock_bh(&bat_priv->vis_hash_lock);
/* properly remove, kill timers ... */
hash_delete(bat_priv->vis_hash, free_info_ref, NULL);
bat_priv->vis_hash = NULL;
bat_priv->my_vis_info = NULL;
spin_unlock_bh(&bat_priv->vis_hash_lock);
}
/* schedule packets for (re)transmission */
static void start_vis_timer(struct bat_priv *bat_priv)
{
INIT_DELAYED_WORK(&bat_priv->vis_work, send_vis_packets);
queue_delayed_work(bat_event_workqueue, &bat_priv->vis_work,
msecs_to_jiffies(VIS_INTERVAL));
}