diff options
Diffstat (limited to 'drivers/staging/batman-adv/vis.c')
| -rw-r--r-- | drivers/staging/batman-adv/vis.c | 564 |
1 files changed, 564 insertions, 0 deletions
diff --git a/drivers/staging/batman-adv/vis.c b/drivers/staging/batman-adv/vis.c new file mode 100644 index 000000000000..f6c9acb289ed --- /dev/null +++ b/drivers/staging/batman-adv/vis.c @@ -0,0 +1,564 @@ +/* + * Copyright (C) 2008-2009 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 "log.h" +#include "soft-interface.h" +#include "hard-interface.h" +#include "hash.h" +#include "compat.h" + +struct hashtable_t *vis_hash; +DEFINE_SPINLOCK(vis_hash_lock); +static struct vis_info *my_vis_info; +static struct list_head send_list; /* always locked with vis_hash_lock */ + +static void start_vis_timer(void); + +/* free the info */ +static void free_info(void *data) +{ + struct vis_info *info = data; + struct recvlist_node *entry, *tmp; + + list_del_init(&info->send_list); + list_for_each_entry_safe(entry, tmp, &info->recv_list, list) { + list_del(&entry->list); + kfree(entry); + } + kfree(info); +} + +/* set the mode of the visualization to client or server */ +void vis_set_mode(int mode) +{ + spin_lock(&vis_hash_lock); + + if (my_vis_info != NULL) + my_vis_info->packet.vis_type = mode; + + spin_unlock(&vis_hash_lock); +} + +/* is_vis_server(), locked outside */ +static int is_vis_server_locked(void) +{ + if (my_vis_info != NULL) + if (my_vis_info->packet.vis_type == VIS_TYPE_SERVER_SYNC) + return 1; + + return 0; +} + +/* get the current set mode */ +int is_vis_server(void) +{ + int ret = 0; + + spin_lock(&vis_hash_lock); + ret = is_vis_server_locked(); + spin_unlock(&vis_hash_lock); + + return ret; +} + +/* Compare two vis packets, used by the hashing algorithm */ +static int vis_info_cmp(void *data1, void *data2) +{ + struct vis_info *d1, *d2; + d1 = data1; + d2 = data2; + return compare_orig(d1->packet.vis_orig, d2->packet.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; + unsigned char *key; + uint32_t hash = 0; + size_t i; + + key = vis_info->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; +} + +/* tries to add one entry to the receive list. */ +static void recv_list_add(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); + list_add_tail(&entry->list, recv_list); +} + +/* returns 1 if this mac is in the recv_list */ +static int recv_list_is_in(struct list_head *recv_list, char *mac) +{ + struct recvlist_node *entry; + + list_for_each_entry(entry, recv_list, list) { + if (memcmp(entry->mac, mac, ETH_ALEN) == 0) + return 1; + } + + 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 vis_packet *vis_packet, + int vis_info_len, int *is_new) +{ + struct vis_info *info, *old_info; + struct vis_info search_elem; + + *is_new = 0; + /* sanity check */ + if (vis_hash == NULL) + return NULL; + + /* see if the packet is already in vis_hash */ + memcpy(search_elem.packet.vis_orig, vis_packet->vis_orig, ETH_ALEN); + old_info = hash_find(vis_hash, &search_elem); + + if (old_info != NULL) { + if (vis_packet->seqno - old_info->packet.seqno <= 0) { + if (old_info->packet.seqno == vis_packet->seqno) { + recv_list_add(&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(vis_hash, old_info); + free_info(old_info); + } + + info = kmalloc(sizeof(struct vis_info) + vis_info_len, GFP_ATOMIC); + if (info == NULL) + return NULL; + + INIT_LIST_HEAD(&info->send_list); + INIT_LIST_HEAD(&info->recv_list); + info->first_seen = jiffies; + memcpy(&info->packet, vis_packet, + sizeof(struct vis_packet) + vis_info_len); + + /* initialize and add new packet. */ + *is_new = 1; + + /* repair if entries is longer than packet. */ + if (info->packet.entries * sizeof(struct vis_info_entry) > vis_info_len) + info->packet.entries = vis_info_len / sizeof(struct vis_info_entry); + + recv_list_add(&info->recv_list, info->packet.sender_orig); + + /* try to add it */ + if (hash_add(vis_hash, info) < 0) { + /* did not work (for some reason) */ + free_info(info); + info = NULL; + } + + return info; +} + +/* handle the server sync packet, forward if needed. */ +void receive_server_sync_packet(struct vis_packet *vis_packet, int vis_info_len) +{ + struct vis_info *info; + int is_new; + + spin_lock(&vis_hash_lock); + info = add_packet(vis_packet, vis_info_len, &is_new); + if (info == NULL) + goto end; + + /* only if we are server ourselves and packet is newer than the one in + * hash.*/ + if (is_vis_server_locked() && is_new) { + memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN); + if (list_empty(&info->send_list)) + list_add_tail(&info->send_list, &send_list); + } +end: + spin_unlock(&vis_hash_lock); +} + +/* handle an incoming client update packet and schedule forward if needed. */ +void receive_client_update_packet(struct vis_packet *vis_packet, + int vis_info_len) +{ + struct vis_info *info; + int is_new; + + /* clients shall not broadcast. */ + if (is_bcast(vis_packet->target_orig)) + return; + + spin_lock(&vis_hash_lock); + info = add_packet(vis_packet, vis_info_len, &is_new); + if (info == NULL) + goto end; + /* note that outdated packets will be dropped at this point. */ + + + /* send only if we're the target server or ... */ + if (is_vis_server_locked() && + is_my_mac(info->packet.target_orig) && + is_new) { + info->packet.vis_type = VIS_TYPE_SERVER_SYNC; /* upgrade! */ + memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN); + if (list_empty(&info->send_list)) + list_add_tail(&info->send_list, &send_list); + + /* ... we're not the recipient (and thus need to forward). */ + } else if (!is_my_mac(info->packet.target_orig)) { + if (list_empty(&info->send_list)) + list_add_tail(&info->send_list, &send_list); + } +end: + spin_unlock(&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 vis_info *info) +{ + struct hash_it_t *hashit = NULL; + struct orig_node *orig_node; + int best_tq = -1; + + while (NULL != (hashit = hash_iterate(orig_hash, hashit))) { + orig_node = hashit->bucket->data; + if ((orig_node != NULL) && + (orig_node->router != NULL) && + (orig_node->flags & VIS_SERVER) && + (orig_node->router->tq_avg > best_tq)) { + best_tq = orig_node->router->tq_avg; + memcpy(info->packet.target_orig, orig_node->orig, + ETH_ALEN); + } + } + return best_tq; +} + +/* Return true if the vis packet is full. */ +static bool vis_packet_full(struct vis_info *info) +{ + if (info->packet.entries + 1 > + (1000 - sizeof(struct vis_info)) / sizeof(struct vis_info_entry)) + 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(void) +{ + struct hash_it_t *hashit = NULL; + struct orig_node *orig_node; + struct vis_info *info = (struct vis_info *)my_vis_info; + struct vis_info_entry *entry, *entry_array; + struct hna_local_entry *hna_local_entry; + int best_tq = -1; + unsigned long flags; + + info->first_seen = jiffies; + + spin_lock(&orig_hash_lock); + memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN); + info->packet.ttl = TTL; + info->packet.seqno++; + info->packet.entries = 0; + + if (!is_vis_server_locked()) { + best_tq = find_best_vis_server(info); + if (best_tq < 0) { + spin_unlock(&orig_hash_lock); + return -1; + } + } + hashit = NULL; + + entry_array = (struct vis_info_entry *) + ((char *)info + sizeof(struct vis_info)); + + while (NULL != (hashit = hash_iterate(orig_hash, hashit))) { + orig_node = hashit->bucket->data; + if (orig_node->router != NULL + && compare_orig(orig_node->router->addr, orig_node->orig) + && orig_node->batman_if + && (orig_node->batman_if->if_active == IF_ACTIVE) + && orig_node->router->tq_avg > 0) { + + /* fill one entry into buffer. */ + entry = &entry_array[info->packet.entries]; + memcpy(entry->src, orig_node->batman_if->net_dev->dev_addr, ETH_ALEN); + memcpy(entry->dest, orig_node->orig, ETH_ALEN); + entry->quality = orig_node->router->tq_avg; + info->packet.entries++; + + if (vis_packet_full(info)) { + spin_unlock(&orig_hash_lock); + return 0; + } + } + } + + spin_unlock(&orig_hash_lock); + + hashit = NULL; + spin_lock_irqsave(&hna_local_hash_lock, flags); + while (NULL != (hashit = hash_iterate(hna_local_hash, hashit))) { + hna_local_entry = hashit->bucket->data; + entry = &entry_array[info->packet.entries]; + memset(entry->src, 0, ETH_ALEN); + memcpy(entry->dest, hna_local_entry->addr, ETH_ALEN); + entry->quality = 0; /* 0 means HNA */ + info->packet.entries++; + + if (vis_packet_full(info)) { + spin_unlock_irqrestore(&hna_local_hash_lock, flags); + return 0; + } + } + spin_unlock_irqrestore(&hna_local_hash_lock, flags); + return 0; +} + +static void purge_vis_packets(void) +{ + struct hash_it_t *hashit = NULL; + struct vis_info *info; + + while (NULL != (hashit = hash_iterate(vis_hash, hashit))) { + info = hashit->bucket->data; + if (info == my_vis_info) /* never purge own data. */ + continue; + if (time_after(jiffies, + info->first_seen + (VIS_TIMEOUT/1000)*HZ)) { + hash_remove_bucket(vis_hash, hashit); + free_info(info); + } + } +} + +static void broadcast_vis_packet(struct vis_info *info, int packet_length) +{ + struct hash_it_t *hashit = NULL; + struct orig_node *orig_node; + + spin_lock(&orig_hash_lock); + + /* send to all routers in range. */ + while (NULL != (hashit = hash_iterate(orig_hash, hashit))) { + orig_node = hashit->bucket->data; + + /* if it's a vis server and reachable, send it. */ + if (orig_node && + (orig_node->flags & VIS_SERVER) && + orig_node->batman_if && + orig_node->router) { + + /* don't send it if we already received the packet from + * this node. */ + if (recv_list_is_in(&info->recv_list, orig_node->orig)) + continue; + + memcpy(info->packet.target_orig, + orig_node->orig, ETH_ALEN); + + send_raw_packet((unsigned char *) &info->packet, + packet_length, + orig_node->batman_if, + orig_node->router->addr); + } + } + memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN); + spin_unlock(&orig_hash_lock); +} + +static void unicast_vis_packet(struct vis_info *info, int packet_length) +{ + struct orig_node *orig_node; + + spin_lock(&orig_hash_lock); + orig_node = ((struct orig_node *) + hash_find(orig_hash, info->packet.target_orig)); + + if ((orig_node != NULL) && + (orig_node->batman_if != NULL) && + (orig_node->router != NULL)) { + send_raw_packet((unsigned char *) &info->packet, packet_length, + orig_node->batman_if, + orig_node->router->addr); + } + spin_unlock(&orig_hash_lock); +} + +/* only send one vis packet. called from send_vis_packets() */ +static void send_vis_packet(struct vis_info *info) +{ + int packet_length; + + if (info->packet.ttl < 2) { + debug_log(LOG_TYPE_NOTICE, + "Error - can't send vis packet: ttl exceeded\n"); + return; + } + + memcpy(info->packet.sender_orig, mainIfAddr, ETH_ALEN); + info->packet.ttl--; + + packet_length = sizeof(struct vis_packet) + + info->packet.entries * sizeof(struct vis_info_entry); + + if (is_bcast(info->packet.target_orig)) + broadcast_vis_packet(info, packet_length); + else + unicast_vis_packet(info, packet_length); + info->packet.ttl++; /* restore TTL */ +} + +/* called from timer; send (and maybe generate) vis packet. */ +static void send_vis_packets(struct work_struct *work) +{ + struct vis_info *info, *temp; + + spin_lock(&vis_hash_lock); + purge_vis_packets(); + + if (generate_vis_packet() == 0) + /* schedule if generation was successful */ + list_add_tail(&my_vis_info->send_list, &send_list); + + list_for_each_entry_safe(info, temp, &send_list, send_list) { + list_del_init(&info->send_list); + send_vis_packet(info); + } + spin_unlock(&vis_hash_lock); + start_vis_timer(); +} +static DECLARE_DELAYED_WORK(vis_timer_wq, send_vis_packets); + +/* 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(void) +{ + if (vis_hash) + return 1; + + spin_lock(&vis_hash_lock); + + vis_hash = hash_new(256, vis_info_cmp, vis_info_choose); + if (!vis_hash) { + debug_log(LOG_TYPE_CRIT, "Can't initialize vis_hash\n"); + goto err; + } + + my_vis_info = kmalloc(1000, GFP_ATOMIC); + if (!my_vis_info) { + debug_log(LOG_TYPE_CRIT, "Can't initialize vis packet\n"); + goto err; + } + + /* prefill the vis info */ + my_vis_info->first_seen = jiffies - atomic_read(&vis_interval); + INIT_LIST_HEAD(&my_vis_info->recv_list); + INIT_LIST_HEAD(&my_vis_info->send_list); + my_vis_info->packet.version = COMPAT_VERSION; + my_vis_info->packet.packet_type = BAT_VIS; + my_vis_info->packet.vis_type = VIS_TYPE_CLIENT_UPDATE; + my_vis_info->packet.ttl = TTL; + my_vis_info->packet.seqno = 0; + my_vis_info->packet.entries = 0; + + INIT_LIST_HEAD(&send_list); + + memcpy(my_vis_info->packet.vis_orig, mainIfAddr, ETH_ALEN); + memcpy(my_vis_info->packet.sender_orig, mainIfAddr, ETH_ALEN); + + if (hash_add(vis_hash, my_vis_info) < 0) { + debug_log(LOG_TYPE_CRIT, + "Can't add own vis packet into hash\n"); + free_info(my_vis_info); /* not in hash, need to remove it + * manually. */ + goto err; + } + + spin_unlock(&vis_hash_lock); + start_vis_timer(); + return 1; + +err: + spin_unlock(&vis_hash_lock); + vis_quit(); + return 0; +} + +/* shutdown vis-server */ +void vis_quit(void) +{ + if (!vis_hash) + return; + + cancel_delayed_work_sync(&vis_timer_wq); + + spin_lock(&vis_hash_lock); + /* properly remove, kill timers ... */ + hash_delete(vis_hash, free_info); + vis_hash = NULL; + my_vis_info = NULL; + spin_unlock(&vis_hash_lock); +} + +/* schedule packets for (re)transmission */ +static void start_vis_timer(void) +{ + queue_delayed_work(bat_event_workqueue, &vis_timer_wq, + (atomic_read(&vis_interval)/1000) * HZ); +} + |