With this feature unicast packets can be send in a redundancy bonding instead of throughput bonding mode on all interfaces available towards a common node. This shall increase the robustness of unicast data transfer / decrease packet loss in cases where bursty packet loss on only one channel, which batman-adv's link quality measurements cannot detect, is to be expected or where batman-adv's metric adaptation is expected to be too slow for certain scenarios.
Signed-off-by: Linus Lüssing <[email protected]> --- main.h | 5 ++ packet.h | 8 ++++ routing.c | 117 ++++++++++++++++++++++++++++++++++++++++++++++++----- routing.h | 3 +- soft-interface.c | 8 +++- types.h | 1 + unicast.c | 10 +++-- unicast.h | 2 +- 8 files changed, 135 insertions(+), 19 deletions(-) diff --git a/batman-adv/main.h b/batman-adv/main.h index bd8470d..862643a 100644 --- a/batman-adv/main.h +++ b/batman-adv/main.h @@ -97,6 +97,11 @@ * Vis */ +/* Bonding modes */ +#define THROUGHPUT_BONDING 1 +#define REDUNDANT_BONDING 2 + + /* * Kernel headers */ diff --git a/batman-adv/packet.h b/batman-adv/packet.h index ae7a0ce..e5a897c 100644 --- a/batman-adv/packet.h +++ b/batman-adv/packet.h @@ -30,6 +30,7 @@ #define BAT_BCAST 0x04 #define BAT_VIS 0x05 #define BAT_UNICAST_FRAG 0x06 +#define BAT_UNICAST_SAFE 0x07 /* this file is included by batctl which needs these defines */ #define COMPAT_VERSION 12 @@ -101,6 +102,13 @@ struct unicast_packet { uint8_t dest[6]; } __packed; +struct unicast_packet_safe { + struct batman_header header; + uint8_t dest[6]; + uint8_t orig[6]; + uint32_t seqno; +} __packed; + struct unicast_frag_packet { struct batman_header header; uint8_t dest[6]; diff --git a/batman-adv/routing.c b/batman-adv/routing.c index 3fceca0..0797ab5 100644 --- a/batman-adv/routing.c +++ b/batman-adv/routing.c @@ -1017,10 +1017,77 @@ out: return ret; } +static int unicast_to_unicast_safe(struct sk_buff *skb, + struct bat_priv *bat_priv) +{ + struct unicast_packet unicast_packet; + struct unicast_packet_safe *unicast_packet_safe; + + memcpy(&unicast_packet, skb->data, sizeof(unicast_packet)); + if (my_skb_head_push(skb, sizeof(struct unicast_packet_safe) - + sizeof(struct unicast_packet)) < 0) + return -1; + + unicast_packet_safe = (struct unicast_packet_safe *) skb->data; + unicast_packet_safe->header = unicast_packet.header; + memcpy(unicast_packet_safe->dest, unicast_packet.dest, ETH_ALEN); + unicast_packet_safe->header.packet_type = BAT_UNICAST_SAFE; + memcpy(unicast_packet_safe->orig, + bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN); + unicast_packet_safe->seqno = + htonl(atomic_inc_return(&bat_priv->dup_seqno)); + + return 0; +} + +static void red_bonding_copy(struct sk_buff *skb, struct list_head *bond_list, + struct hlist_head *packet_list, + struct bat_priv *bat_priv) +{ + struct neigh_node *neigh_node; + struct packet_list_entry *entry; + int num_entries = 0; + int packet_type = ((struct batman_header *) skb->data)->packet_type; + + /* We only expect either BAT_UNICAST or BAT_UNICAST_SAFE here */ + if (packet_type == BAT_UNICAST) { + if (unicast_to_unicast_safe(skb, bat_priv) < 0) { + kfree_skb(skb); + return; + } + } + + list_for_each_entry_rcu(neigh_node, bond_list, bonding_list) { + entry = kmalloc(sizeof(struct packet_list_entry), GFP_ATOMIC); + if (!entry) { + kfree_skb(skb); + return; + } + if (!num_entries) + entry->skb = skb; + else { + entry->skb = skb_copy(skb, GFP_ATOMIC); + if (!entry->skb) { + kfree_skb(skb); + kfree(entry); + return; + } + } + entry->neigh_node = neigh_node; + if (!atomic_inc_not_zero(&neigh_node->refcount)) { + kfree_skb(entry->skb); + kfree(entry); + continue; + } + hlist_add_head(&entry->list, packet_list); + num_entries++; + } +} + /* find a suitable router for this originator, and use * bonding if possible. increases the found neighbors * refcount.*/ -static void find_router(struct orig_node *orig_node, +static void find_router(int bonding_mode, struct orig_node *orig_node, struct batman_if *recv_if, struct sk_buff *skb, struct hlist_head *packet_list) @@ -1031,7 +1098,6 @@ static void find_router(struct orig_node *orig_node, struct neigh_node *router, *first_candidate, *tmp_neigh_node; struct packet_list_entry *entry; static uint8_t zero_mac[ETH_ALEN] = {0, 0, 0, 0, 0, 0}; - int bonding_enabled; if (!orig_node) return; @@ -1043,7 +1109,6 @@ static void find_router(struct orig_node *orig_node, /* without bonding, the first node should * always choose the default router. */ - bonding_enabled = atomic_read(&bat_priv->bonding); rcu_read_lock(); /* select default router to output */ @@ -1054,7 +1119,7 @@ static void find_router(struct orig_node *orig_node, return; } - if ((!recv_if) && (!bonding_enabled)) + if ((!recv_if) && (!bonding_mode)) goto return_router; /* if we have something in the primary_addr, we can search @@ -1090,7 +1155,7 @@ static void find_router(struct orig_node *orig_node, first_candidate = NULL; router = NULL; - if (bonding_enabled) { + if (bonding_mode == THROUGHPUT_BONDING) { /* in the bonding case, send the packets in a round * robin fashion over the remaining interfaces. */ @@ -1126,6 +1191,11 @@ static void find_router(struct orig_node *orig_node, &router->bonding_list); spin_unlock_bh(&primary_orig_node->neigh_list_lock); + } else if (bonding_mode == REDUNDANT_BONDING) { + red_bonding_copy(skb, &primary_orig_node->bond_list, + packet_list, bat_priv); + rcu_read_unlock(); + return; } else { /* if bonding is disabled, use the best of the * remaining candidates which are not using @@ -1202,12 +1272,16 @@ static int check_unicast_packet(struct sk_buff *skb, int hdr_size) return 0; } -int route_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if, +int route_unicast_packet(int bonding_mode, struct sk_buff *skb, + struct batman_if *recv_if, struct orig_node *orig_node) { int ret = NET_RX_DROP; struct hlist_head packet_list; + if (!orig_node) + goto out; + INIT_HLIST_HEAD(&packet_list); /* create a copy of the skb, if needed, to modify it. */ @@ -1215,10 +1289,10 @@ int route_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if, goto out; /* creates the (initial) packet list */ - find_router(orig_node, recv_if, skb, &packet_list); + find_router(bonding_mode, orig_node, recv_if, skb, &packet_list); /* split packets that won't fit or maybe buffer fragments */ - frag_packet_list(orig_node->bat_priv, &packet_list); + frag_packet_list(bonding_mode, orig_node->bat_priv, &packet_list); /* route them */ send_packet_list(&packet_list); @@ -1237,6 +1311,7 @@ int recv_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if) struct unicast_packet *unicast_packet; struct orig_node *orig_node; int hdr_size = sizeof(struct unicast_packet); + int bonding_mode; if (check_unicast_packet(skb, hdr_size) < 0) return NET_RX_DROP; @@ -1249,8 +1324,10 @@ int recv_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if) return NET_RX_SUCCESS; } + bonding_mode = atomic_read(&bat_priv->bonding) << + atomic_read(&bat_priv->red_bonding); orig_node = hash_find_orig(bat_priv, unicast_packet->dest); - return route_unicast_packet(skb, recv_if, orig_node); + return route_unicast_packet(bonding_mode, skb, recv_if, orig_node); } int recv_ucast_frag_packet(struct sk_buff *skb, struct batman_if *recv_if) @@ -1260,7 +1337,7 @@ int recv_ucast_frag_packet(struct sk_buff *skb, struct batman_if *recv_if) struct orig_node *orig_node; int hdr_size = sizeof(struct unicast_frag_packet); struct sk_buff *new_skb = NULL; - int ret; + int ret, bonding_mode; if (check_unicast_packet(skb, hdr_size) < 0) return NET_RX_DROP; @@ -1284,8 +1361,26 @@ int recv_ucast_frag_packet(struct sk_buff *skb, struct batman_if *recv_if) return NET_RX_SUCCESS; } + /* The redundant bonding mode currently cannot handle fragmented + * packets, therefore need to defrag them first */ + bonding_mode = atomic_read(&bat_priv->bonding) << + atomic_read(&bat_priv->red_bonding); + + if (bonding_mode == REDUNDANT_BONDING) { + ret = frag_reassemble_skb(skb, bat_priv, &new_skb); + + if (ret == NET_RX_DROP) + return NET_RX_DROP; + + /* packet was buffered for late merge */ + if (!new_skb) + return NET_RX_SUCCESS; + + skb = new_skb; + } + orig_node = hash_find_orig(bat_priv, unicast_packet->dest); - return route_unicast_packet(skb, recv_if, orig_node); + return route_unicast_packet(bonding_mode, skb, recv_if, orig_node); } diff --git a/batman-adv/routing.h b/batman-adv/routing.h index 43a2609..01fab8d 100644 --- a/batman-adv/routing.h +++ b/batman-adv/routing.h @@ -30,7 +30,8 @@ void receive_bat_packet(struct ethhdr *ethhdr, void update_routes(struct bat_priv *bat_priv, struct orig_node *orig_node, struct neigh_node *neigh_node, unsigned char *hna_buff, int hna_buff_len); -int route_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if, +int route_unicast_packet(int bonding_mode, struct sk_buff *skb, + struct batman_if *recv_if, struct orig_node *orig_node); int recv_icmp_packet(struct sk_buff *skb, struct batman_if *recv_if); int recv_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if); diff --git a/batman-adv/soft-interface.c b/batman-adv/soft-interface.c index 25db300..c6035fe 100644 --- a/batman-adv/soft-interface.c +++ b/batman-adv/soft-interface.c @@ -443,7 +443,7 @@ void interface_rx(struct net_device *soft_iface, struct ethhdr *ethhdr; struct vlan_ethhdr *vhdr; short vid = -1; - int ret; + int ret, bonding_mode; /* check if enough space is available for pulling, and pull */ if (!pskb_may_pull(skb, hdr_size)) @@ -484,8 +484,11 @@ void interface_rx(struct net_device *soft_iface, memcpy(unicast_packet->dest, bat_priv->softif_neigh->addr, ETH_ALEN); + bonding_mode = atomic_read(&bat_priv->bonding) << + atomic_read(&bat_priv->red_bonding); orig_node = hash_find_orig(bat_priv, unicast_packet->dest); - ret = route_unicast_packet(skb, recv_if, orig_node); + ret = route_unicast_packet(bonding_mode, skb, recv_if, + orig_node); if (ret == NET_RX_DROP) goto dropped; @@ -604,6 +607,7 @@ struct net_device *softif_create(char *name) atomic_set(&bat_priv->mesh_state, MESH_INACTIVE); atomic_set(&bat_priv->bcast_seqno, 1); + atomic_set(&bat_priv->dup_seqno, 1); atomic_set(&bat_priv->hna_local_changed, 0); bat_priv->primary_if = NULL; diff --git a/batman-adv/types.h b/batman-adv/types.h index c2ddd0a..5401498 100644 --- a/batman-adv/types.h +++ b/batman-adv/types.h @@ -141,6 +141,7 @@ struct bat_priv { atomic_t hop_penalty; /* uint */ atomic_t log_level; /* uint */ atomic_t bcast_seqno; + atomic_t dup_seqno; atomic_t bcast_queue_left; atomic_t batman_queue_left; char num_ifaces; diff --git a/batman-adv/unicast.c b/batman-adv/unicast.c index b824315..aa46103 100644 --- a/batman-adv/unicast.c +++ b/batman-adv/unicast.c @@ -30,7 +30,6 @@ #include "routing.h" #include "hard-interface.h" - static struct sk_buff *frag_merge_packet(struct list_head *head, struct frag_packet_list_entry *tfp, struct sk_buff *skb) @@ -333,7 +332,7 @@ static inline int frag_can_reassemble(struct sk_buff *skb, int mtu) return merged_size <= mtu; } -void frag_packet_list(struct bat_priv *bat_priv, +void frag_packet_list(int bonding, struct bat_priv *bat_priv, struct hlist_head *packet_list) { struct packet_list_entry *entry; @@ -347,6 +346,7 @@ void frag_packet_list(struct bat_priv *bat_priv, switch (packet_type) { case BAT_UNICAST: if (!atomic_read(&bat_priv->fragmentation) || + bonding == REDUNDANT_BONDING || entry->skb->len <= entry->neigh_node->if_incoming->net_dev->mtu) break; @@ -372,7 +372,7 @@ int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv) struct ethhdr *ethhdr = (struct ethhdr *)skb->data; struct unicast_packet *unicast_packet; struct orig_node *orig_node; - int ret = NET_RX_DROP; + int ret = NET_RX_DROP, bonding_mode; /* get routing information */ if (is_multicast_ether_addr(ethhdr->h_dest)) { @@ -398,7 +398,9 @@ route: /* copy the destination for faster routing */ memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN); - ret = route_unicast_packet(skb, NULL, orig_node); + bonding_mode = atomic_read(&bat_priv->bonding) << + atomic_read(&bat_priv->red_bonding); + ret = route_unicast_packet(bonding_mode, skb, NULL, orig_node); out: if (ret == NET_RX_DROP) diff --git a/batman-adv/unicast.h b/batman-adv/unicast.h index 1b4dbb0..e87597b 100644 --- a/batman-adv/unicast.h +++ b/batman-adv/unicast.h @@ -30,7 +30,7 @@ int frag_reassemble_skb(struct sk_buff *skb, struct bat_priv *bat_priv, struct sk_buff **new_skb); void frag_list_free(struct list_head *head); -void frag_packet_list(struct bat_priv *bat_priv, +void frag_packet_list(int bonding, struct bat_priv *bat_priv, struct hlist_head *packet_list); int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv); -- 1.7.2.3
