Changeset 1551

Timestamp:

01/17/10 21:33:37 (8 months ago)

Author:

simon

Message:

batman-adv: Add bonding functionality

This patch introduces bonding functionality to batman-advanced, targeted
for the 0.3 release. As we are able to route the payload traffic as we
want, we may use multiple interfaces on multihomed hosts to transfer data
to achieve higher bandwidth. This can be considered as "light Multi Path
Routing" for single hop connections.

To detect which interfaces of a peer node belong to the same host, a
new flag PRIMARIES_FIRST_HOP is introduced. This flag is set on the first hop
of OGMs of the primary (first) interface, which is broadcasted on all
interfaces. When receiving such an OGM, we can learn which interfaces
belong to the same host (by assigning them to the primary originator).

Bonding works by sending packets in a round-robin fashion to the available
interfaces of a neighbor host, if multiple interfaces are available. The
neighbor interfaces should be almost equally good to reach.

To avoid interferences (i.e. sending on the same channel), only neighbor
interfaces with different mac addresses and different outgoing interfaces
are considered as candidates.

Bonding is deactivated by default, and can be activated by

echo 1 > /proc/net/batman-adv/bonding

for each individual node.

Signed-off-by: Simon Wunderlich <siwu@…>

Location:

trunk/batman-adv-kernelland

Files:

• hard-interface.c (modified) (1 diff)
• main.c (modified) (2 diffs)
• main.h (modified) (2 diffs)
• originator.c (modified) (1 diff)
• packet.h (modified) (1 diff)
• proc.c (modified) (5 diffs)
• proc.h (modified) (1 diff)
• routing.c (modified) (6 diffs)
• routing.h (modified) (1 diff)
• send.c (modified) (2 diffs)
• soft-interface.c (modified) (4 diffs)
• types.h (modified) (3 diffs)

trunk/batman-adv-kernelland/hard-interface.c

@@ -313 +313 @@
         batman_packet->packet_type = BAT_PACKET;
         batman_packet->version = COMPAT_VERSION;
-        batman_packet->flags = 0x00;
-        batman_packet->ttl = (batman_if->if_num > 0 ? 2 : TTL);
-        batman_packet->flags = 0;
+        batman_packet->flags = batman_if->if_num > 0 ?
+                        0x00 : PRIMARIES_FIRST_HOP;
+        batman_packet->ttl = batman_if->if_num > 0 ? 2 : TTL;
         batman_packet->tq = TQ_MAX_VALUE;
         batman_packet->num_hna = 0;

trunk/batman-adv-kernelland/main.c

@@ -48 +48 @@
 atomic_t vis_interval;
 atomic_t aggregation_enabled;
+atomic_t bonding_enabled;
 int16_t num_hna;
 int16_t num_ifs;
@@ -88 +89 @@
                                          * for debugging now. */
         atomic_set(&aggregation_enabled, 1);
+        atomic_set(&bonding_enabled, 0);
         atomic_set(&gw_mode, GW_MODE_OFF);
         atomic_set(&gw_srv_class, 0);

trunk/batman-adv-kernelland/main.h

@@ -58 +58 @@
 #define LOG_BUF_LEN 8192          /* has to be a power of 2 */
 #define ETH_STR_LEN 20
+
+/* how much worse secondary interfaces may be to
+ * to be considered as bonding candidates */
+
+#define BONDING_TQ_THRESHOLD    50
 
 #define MAX_AGGREGATION_BYTES 512 /* should not be bigger than 512 bytes or
@@ -132 +137 @@
 extern atomic_t vis_interval;
 extern atomic_t aggregation_enabled;
+extern atomic_t bonding_enabled;
 extern int16_t num_hna;
 extern int16_t num_ifs;

trunk/batman-adv-kernelland/originator.c

@@ -222 +222 @@
                 return true;
         } else {
-                if (purge_orig_neighbors(orig_node, &best_neigh_node))
+                if (purge_orig_neighbors(orig_node, &best_neigh_node)) {
                         update_routes(orig_node, best_neigh_node,
                                       orig_node->hna_buff,
                                       orig_node->hna_buff_len);
+                        /* update bonding candidates, we could have lost
+                         * some candidates. */
+                        update_bonding_candidates(orig_node);
+                }
         }
         return false;

trunk/batman-adv-kernelland/packet.h

@@ -32 +32 @@
 #define DIRECTLINK 0x40
 #define VIS_SERVER 0x20
+#define PRIMARIES_FIRST_HOP 0x10
 
 /* ICMP message types */

trunk/batman-adv-kernelland/proc.c

@@ -37 +37 @@
 static struct proc_dir_entry *proc_transt_global_file;
 static struct proc_dir_entry *proc_vis_srv_file, *proc_vis_data_file;
-static struct proc_dir_entry *proc_aggr_file;
+static struct proc_dir_entry *proc_aggr_file, *proc_bond_file;
 static struct proc_dir_entry *proc_gw_mode_file, *proc_gw_srv_list_file;
 
@@ -559 +559 @@
 
 
+static int proc_bond_read(struct seq_file *seq, void *offset)
+{
+        seq_printf(seq, "%i\n", atomic_read(&bonding_enabled));
+
+        return 0;
+}
+
+static ssize_t proc_bond_write(struct file *file, const char __user *buffer,
+                               size_t count, loff_t *ppos)
+{
+        char *bond_string;
+        int not_copied = 0;
+        unsigned long bonding_enabled_tmp;
+        int retval;
+
+        bond_string = kmalloc(count, GFP_KERNEL);
+
+        if (!bond_string)
+                return -ENOMEM;
+
+        not_copied = copy_from_user(bond_string, buffer, count);
+        bond_string[count - not_copied - 1] = 0;
+
+        retval = strict_strtoul(bond_string, 10, &bonding_enabled_tmp);
+
+        if (retval || bonding_enabled_tmp > 1) {
+                printk(KERN_ERR "batman-adv: Bonding can only be enabled (1) or disabled (0), given value: %li\n", bonding_enabled_tmp);
+        } else {
+                printk(KERN_INFO "batman-adv:Changing bonding from: %s (%i) to: %s (%li)\n",
+                       (atomic_read(&bonding_enabled) == 1 ?
+                        "enabled" : "disabled"),
+                       atomic_read(&bonding_enabled),
+                       (bonding_enabled_tmp == 1 ? "enabled" : "disabled"),
+                       bonding_enabled_tmp);
+                atomic_set(&bonding_enabled,
+                                                (unsigned)bonding_enabled_tmp);
+        }
+
+        kfree(bond_string);
+        return count;
+}
+
+static int proc_bond_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, proc_bond_read, NULL);
+}
+
 /* satisfying different prototypes ... */
 static ssize_t proc_dummy_write(struct file *file, const char __user *buffer,
@@ -593 +640 @@
 };
 
+static const struct file_operations proc_bond_fops = {
+        .owner          = THIS_MODULE,
+        .open           = proc_bond_open,
+        .read           = seq_read,
+        .write          = proc_bond_write,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+};
+
 static const struct file_operations proc_vis_srv_fops = {
         .owner          = THIS_MODULE,
@@ -687 +743 @@
         if (proc_gw_srv_list_file)
                 remove_proc_entry(PROC_FILE_GW_SRV_LIST, proc_batman_dir);
+
+        if (proc_bond_file)
+                remove_proc_entry(PROC_FILE_BOND, proc_batman_dir);
+
 
         if (proc_batman_dir)
@@ -816 +876 @@
         }
 
-        return 0;
-}
+        proc_bond_file = create_proc_entry(PROC_FILE_BOND, S_IWUSR | S_IRUGO,
+                                           proc_batman_dir);
+        if (proc_bond_file) {
+                proc_bond_file->proc_fops = &proc_bond_fops;
+        } else {
+                printk(KERN_ERR "batman-adv: Registering the '/proc/net/%s/%s' file failed\n", PROC_ROOT_DIR, PROC_FILE_BOND);
+                cleanup_procfs();
+                return -EFAULT;
+        }
+
+        return 0;
+}

trunk/batman-adv-kernelland/proc.h

@@ -35 +35 @@
 #define PROC_FILE_VIS_DATA "vis_data"
 #define PROC_FILE_AGGR "aggregate_ogm"
+#define PROC_FILE_BOND "bonding"
 #define PROC_FILE_GW_MODE "gateway_mode"
 #define PROC_FILE_GW_SRV_LIST "gateway_srv_list"

trunk/batman-adv-kernelland/routing.c

@@ -364 +364 @@
 }
 
+/* copy primary address for bonding */
+static void mark_bonding_address(struct orig_node *orig_node,
+                                struct orig_node *orig_neigh_node,
+                                struct batman_packet *batman_packet)
+
+{
+        /* don't care if bonding is not enabled */
+        if (!atomic_read(&bonding_enabled)) {
+                orig_node->bond.candidates = 0;
+                return;
+        }
+
+        if (batman_packet->flags & PRIMARIES_FIRST_HOP)
+                memcpy(orig_neigh_node->primary_addr,
+                                                orig_node->orig, ETH_ALEN);
+         else
+                return;
+}
+
+/* mark possible bonding candidates in the neighbor list */
+void update_bonding_candidates(struct orig_node *orig_node)
+{
+        int candidates;
+        int interference_candidate;
+        int best_tq;
+        struct neigh_node *tmp_neigh_node, *tmp_neigh_node2;
+    struct neigh_node *first_candidate, *last_candidate;
+
+        /* don't care if bonding is not enabled */
+        if (!atomic_read(&bonding_enabled)) {
+                orig_node->bond.candidates = 0;
+                return;
+        }
+
+        /* update the candidates for this originator */
+        if (!orig_node->router) {
+                orig_node->bond.candidates = 0;
+                return;
+        }
+
+        best_tq = orig_node->router->tq_avg;
+
+        /* update bonding candidates */
+
+        candidates = 0;
+
+        /* mark other nodes which also received "PRIMARIES FIRST HOP" packets
+         * as "bonding partner" */
+
+        /* first, zero the list */
+        list_for_each_entry(tmp_neigh_node, &orig_node->neigh_list, list) {
+                tmp_neigh_node->next_bond_candidate = NULL;
+        }
+
+        first_candidate = NULL;
+        last_candidate = NULL;
+        list_for_each_entry(tmp_neigh_node, &orig_node->neigh_list, list) {
+
+                /* only consider if it has the same primary address ...  */
+                if (memcmp(orig_node->orig,
+                                tmp_neigh_node->orig_node->primary_addr,
+                                ETH_ALEN) != 0)
+                        continue;
+
+                /* ... and is good enough to be considered */
+                if (tmp_neigh_node->tq_avg < best_tq - BONDING_TQ_THRESHOLD)
+                        continue;
+
+                /* check if we have another candidate with the same
+                 * mac address or interface. If we do, we won't
+                 * select this candidate because of possible interference. */
+
+                interference_candidate = 0;
+                list_for_each_entry(tmp_neigh_node2,
+                                &orig_node->neigh_list, list) {
+
+                        if (tmp_neigh_node2 == tmp_neigh_node)
+                                continue;
+
+                        if ((tmp_neigh_node->if_incoming ==
+                                tmp_neigh_node2->if_incoming)
+                                || (memcmp(tmp_neigh_node->addr,
+                                tmp_neigh_node2->addr, ETH_ALEN) == 0)) {
+
+                                interference_candidate = 1;
+                                break;
+                        }
+                }
+                /* don't care further if it is an interference candidate */
+                if (interference_candidate)
+                        continue;
+
+                if (first_candidate == NULL) {
+                        first_candidate = tmp_neigh_node;
+                        tmp_neigh_node->next_bond_candidate = first_candidate;
+                } else
+                        tmp_neigh_node->next_bond_candidate = last_candidate;
+
+                last_candidate = tmp_neigh_node;
+
+                candidates++;
+        }
+
+        if (candidates > 0) {
+                first_candidate->next_bond_candidate = last_candidate;
+                orig_node->bond.selected = first_candidate;
+        }
+
+        orig_node->bond.candidates = candidates;
+}
+
 void receive_bat_packet(struct ethhdr *ethhdr,
                                 struct batman_packet *batman_packet,
@@ -530 +641 @@
                             if_incoming, hna_buff, hna_buff_len, is_duplicate);
 
+        mark_bonding_address(orig_node, orig_neigh_node, batman_packet);
+        update_bonding_candidates(orig_node);
+
         /* is single hop (direct) neighbor */
         if (is_single_hop_neigh) {
@@ -799 +913 @@
 }
 
+/* find a suitable router for this originator, and use
+ * bonding if possible. */
+struct neigh_node *find_router(struct orig_node *orig_node)
+{
+        struct orig_node *primary_orig_node;
+        struct orig_node *router_orig;
+        struct neigh_node *router;
+        static uint8_t zero_mac[ETH_ALEN] = {0, 0, 0, 0, 0, 0};
+
+        if (!orig_node)
+                return NULL;
+
+        if (!orig_node->router)
+                return NULL;
+
+        /* don't care if bonding is not enabled */
+        if (!atomic_read(&bonding_enabled))
+                return orig_node->router;
+
+        router_orig = orig_node->router->orig_node;
+
+        /* if we have something in the primary_addr, we can search
+         * for a potential bonding candidate. */
+        if (memcmp(router_orig->primary_addr, zero_mac, ETH_ALEN) == 0)
+                return orig_node->router;
+
+        /* find the orig_node which has the primary interface. might
+         * even be the same as our orig_node in many cases */
+
+        primary_orig_node = hash_find(orig_hash, router_orig->primary_addr);
+        if (!primary_orig_node)
+                return orig_node->router;
+
+        /* with less than 2 candidates, we can't do any
+         * bonding and prefer the original router. */
+
+        if (primary_orig_node->bond.candidates < 2)
+                return orig_node->router;
+
+        router = primary_orig_node->bond.selected;
+
+        /* sanity check - this should never happen. */
+        if (!router)
+                return orig_node->router;
+
+        /* select the next bonding partner ... */
+        primary_orig_node->bond.selected = router->next_bond_candidate;
+
+        return router;
+}
+
 int recv_unicast_packet(struct sk_buff *skb)
 {
         struct unicast_packet *unicast_packet;
         struct orig_node *orig_node;
+        struct neigh_node *router;
         struct ethhdr *ethhdr;
         struct batman_if *batman_if;
@@ -808 +974 @@
         uint8_t dstaddr[ETH_ALEN];
         int hdr_size = sizeof(struct unicast_packet);
-        int ret;
         unsigned long flags;
 
@@ -843 +1008 @@
         }
 
-        ret = NET_RX_DROP;
         /* get routing information */
         spin_lock_irqsave(&orig_hash_lock, flags);
@@ -849 +1013 @@
                      hash_find(orig_hash, unicast_packet->dest));
 
-        if ((orig_node != NULL) &&
-            (orig_node->batman_if != NULL) &&
-            (orig_node->router != NULL)) {
-
-                /* don't lock while sending the packets ... we therefore
-                 * copy the required data before sending */
-                batman_if = orig_node->batman_if;
-                memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
-                spin_unlock_irqrestore(&orig_hash_lock, flags);
-
-                /* create a copy of the skb, if needed, to modify it. */
-                if (!skb_clone_writable(skb, sizeof(struct unicast_packet))) {
-                        skb_old = skb;
-                        skb = skb_copy(skb, GFP_ATOMIC);
-                        if (!skb)
-                                return NET_RX_DROP;
-                        unicast_packet = (struct unicast_packet *) skb->data;
-                        kfree_skb(skb_old);
-                }
-                /* decrement ttl */
-                unicast_packet->ttl--;
-
-                /* route it */
-                send_skb_packet(skb, batman_if, dstaddr);
-                ret = NET_RX_SUCCESS;
-
-        } else
-                spin_unlock_irqrestore(&orig_hash_lock, flags);
-
-        return ret;
+        router = find_router(orig_node);
+
+        if (!router) {
+                spin_lock_irqsave(&orig_hash_lock, flags);
+                return NET_RX_DROP;
+        }
+
+        /* don't lock while sending the packets ... we therefore
+         * copy the required data before sending */
+
+        batman_if = router->if_incoming;
+        memcpy(dstaddr, router->addr, ETH_ALEN);
+
+        spin_unlock_irqrestore(&orig_hash_lock, flags);
+
+        /* create a copy of the skb, if needed, to modify it. */
+        if (!skb_clone_writable(skb, sizeof(struct unicast_packet))) {
+                skb_old = skb;
+                skb = skb_copy(skb, GFP_ATOMIC);
+                if (!skb)
+                        return NET_RX_DROP;
+                unicast_packet = (struct unicast_packet *) skb->data;
+                kfree_skb(skb_old);
+        }
+
+        /* decrement ttl */
+        unicast_packet->ttl--;
+
+        /* route it */
+        send_skb_packet(skb, batman_if, dstaddr);
+
+        return NET_RX_SUCCESS;
 }
 

trunk/batman-adv-kernelland/routing.h

@@ -39 +39 @@
 int recv_bat_packet(struct sk_buff *skb,
                                 struct batman_if *batman_if);
+struct neigh_node *find_router(struct orig_node *orig_node);
+void update_bonding_candidates(struct orig_node *orig_node);

trunk/batman-adv-kernelland/send.c

@@ -277 +277 @@
 
         if (is_vis_server())
-                batman_packet->flags = VIS_SERVER;
+                batman_packet->flags |= VIS_SERVER;
         else
-                batman_packet->flags = 0;
+                batman_packet->flags &= ~VIS_SERVER;
 
         batman_packet->gw_flags = (uint8_t)atomic_read(&gw_srv_class);
@@ -336 +336 @@
         batman_packet->seqno = htons(batman_packet->seqno);
 
+        /* switch of primaries first hop flag when forwarding */
+        batman_packet->flags &= ~PRIMARIES_FIRST_HOP;
         if (directlink)
                 batman_packet->flags |= DIRECTLINK;

trunk/batman-adv-kernelland/soft-interface.c

@@ -23 +23 @@
 #include "soft-interface.h"
 #include "hard-interface.h"
+#include "routing.h"
 #include "send.h"
 #include "translation-table.h"
@@ -172 +173 @@
 }
 
+
+
 int interface_tx(struct sk_buff *skb, struct net_device *dev)
 {
@@ -177 +180 @@
         struct bcast_packet *bcast_packet;
         struct orig_node *orig_node;
+        struct neigh_node *router;
         struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
         struct bat_priv *priv = netdev_priv(dev);
@@ -239 +243 @@
                         orig_node = transtable_search(ethhdr->h_dest);
 
-                if ((orig_node) &&
-                    (orig_node->batman_if) &&
-                    (orig_node->router)) {
-                        if (my_skb_push(skb, sizeof(struct unicast_packet)) < 0)
-                                goto unlock;
-
-                        unicast_packet = (struct unicast_packet *)skb->data;
-
-                        unicast_packet->version = COMPAT_VERSION;
-                        /* batman packet type: unicast */
-                        unicast_packet->packet_type = BAT_UNICAST;
-                        /* set unicast ttl */
-                        unicast_packet->ttl = TTL;
-                        /* copy the destination for faster routing */
-                        memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
-
-                        /* net_dev won't be available when not active */
-                        if (orig_node->batman_if->if_active != IF_ACTIVE)
-                                goto unlock;
-
-                        /* don't lock while sending the packets ... we therefore
-                         * copy the required data before sending */
-
-                        batman_if = orig_node->batman_if;
-                        memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
-                        spin_unlock_irqrestore(&orig_hash_lock, flags);
-
-                        send_skb_packet(skb, batman_if, dstaddr);
-                } else {
+                router = find_router(orig_node);
+
+                if (!router)
                         goto unlock;
-                }
+
+                /* don't lock while sending the packets ... we therefore
+                 * copy the required data before sending */
+
+                batman_if = router->if_incoming;
+                memcpy(dstaddr, router->addr, ETH_ALEN);
+
+                spin_unlock_irqrestore(&orig_hash_lock, flags);
+
+                if (batman_if->if_active != IF_ACTIVE)
+                        goto dropped;
+
+                if (my_skb_push(skb, sizeof(struct unicast_packet)) < 0)
+                        goto dropped;
+
+                unicast_packet = (struct unicast_packet *)skb->data;
+
+                unicast_packet->version = COMPAT_VERSION;
+                /* batman packet type: unicast */
+                unicast_packet->packet_type = BAT_UNICAST;
+                /* set unicast ttl */
+                unicast_packet->ttl = TTL;
+                /* copy the destination for faster routing */
+                memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
+
+                send_skb_packet(skb, batman_if, dstaddr);
         }
 

trunk/batman-adv-kernelland/types.h

@@ -48 +48 @@
 struct orig_node {               /* structure for orig_list maintaining nodes of mesh */
         uint8_t orig[ETH_ALEN];
+        uint8_t primary_addr[ETH_ALEN]; /* hosts primary interface address */
         struct neigh_node *router;
         struct batman_if *batman_if;
@@ -64 +65 @@
         uint16_t last_bcast_seqno;  /* last broadcast sequence number received by this host */
         struct list_head neigh_list;
+        struct {
+                uint8_t candidates;     /* how many candidates are available */
+                struct neigh_node *selected;    /* next bonding candidate */
+        } bond;
 };
 
@@ -81 +86 @@
         uint8_t tq_avg;
         uint8_t last_ttl;
+        struct neigh_node *next_bond_candidate;
         unsigned long last_valid;            /* when last packet via this neighbor was received */
         TYPE_OF_WORD real_bits[NUM_WORDS];