2 * Copyright (C) 2007-2009 B.A.T.M.A.N. contributors:
4 * Marek Lindner, Simon Wunderlich
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of version 2 of the GNU General Public
8 * License as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
23 #include "aggregation.h"
27 /* calculate the size of the hna information for a given packet */
28 static int hna_len(struct batman_packet
*batman_packet
)
30 return batman_packet
->num_hna
* ETH_ALEN
;
33 /* return true if new_packet can be aggregated with forw_packet */
34 static bool can_aggregate_with(struct batman_packet
*new_batman_packet
,
36 unsigned long send_time
,
38 struct batman_if
*if_incoming
,
39 struct forw_packet
*forw_packet
)
41 struct batman_packet
*batman_packet
=
42 (struct batman_packet
*)forw_packet
->packet_buff
;
43 int aggregated_bytes
= forw_packet
->packet_len
+ packet_len
;
46 * we can aggregate the current packet to this aggregated packet
49 * - the send time is within our MAX_AGGREGATION_MS time
50 * - the resulting packet wont be bigger than
51 * MAX_AGGREGATION_BYTES
54 if (time_before(send_time
, forw_packet
->send_time
) &&
55 (aggregated_bytes
<= MAX_AGGREGATION_BYTES
)) {
58 * check aggregation compatibility
59 * -> direct link packets are broadcasted on
60 * their interface only
61 * -> aggregate packet if the current packet is
62 * a "global" packet as well as the base
66 /* packets without direct link flag and high TTL
67 * are flooded through the net */
69 (!(batman_packet
->flags
& DIRECTLINK
)) &&
70 (batman_packet
->ttl
!= 1) &&
72 /* own packets originating non-primary
73 * interfaces leave only that interface */
74 ((!forw_packet
->own
) ||
75 (forw_packet
->if_incoming
->if_num
== 0)))
78 /* if the incoming packet is sent via this one
79 * interface only - we still can aggregate */
81 (new_batman_packet
->ttl
== 1) &&
82 (forw_packet
->if_incoming
== if_incoming
))
90 /* create a new aggregated packet and add this packet to it */
91 static void new_aggregated_packet(unsigned char *packet_buff
,
93 unsigned long send_time
,
95 struct batman_if
*if_incoming
,
98 struct forw_packet
*forw_packet_aggr
;
100 forw_packet_aggr
= kmalloc(sizeof(struct forw_packet
), GFP_ATOMIC
);
101 if (!forw_packet_aggr
)
104 forw_packet_aggr
->packet_buff
= kmalloc(MAX_AGGREGATION_BYTES
,
106 if (!forw_packet_aggr
->packet_buff
) {
107 kfree(forw_packet_aggr
);
111 INIT_HLIST_NODE(&forw_packet_aggr
->list
);
113 forw_packet_aggr
->packet_len
= packet_len
;
114 memcpy(forw_packet_aggr
->packet_buff
,
116 forw_packet_aggr
->packet_len
);
118 forw_packet_aggr
->own
= own_packet
;
119 forw_packet_aggr
->if_incoming
= if_incoming
;
120 forw_packet_aggr
->num_packets
= 0;
121 forw_packet_aggr
->direct_link_flags
= 0;
122 forw_packet_aggr
->send_time
= send_time
;
124 /* save packet direct link flag status */
126 forw_packet_aggr
->direct_link_flags
|= 1;
128 /* add new packet to packet list */
129 spin_lock(&forw_bat_list_lock
);
130 hlist_add_head(&forw_packet_aggr
->list
, &forw_bat_list
);
131 spin_unlock(&forw_bat_list_lock
);
133 /* start timer for this packet */
134 INIT_DELAYED_WORK(&forw_packet_aggr
->delayed_work
,
135 send_outstanding_bat_packet
);
136 queue_delayed_work(bat_event_workqueue
,
137 &forw_packet_aggr
->delayed_work
,
138 send_time
- jiffies
);
141 /* aggregate a new packet into the existing aggregation */
142 static void aggregate(struct forw_packet
*forw_packet_aggr
,
143 unsigned char *packet_buff
,
147 memcpy((forw_packet_aggr
->packet_buff
+ forw_packet_aggr
->packet_len
),
148 packet_buff
, packet_len
);
149 forw_packet_aggr
->packet_len
+= packet_len
;
150 forw_packet_aggr
->num_packets
++;
152 /* save packet direct link flag status */
154 forw_packet_aggr
->direct_link_flags
|=
155 (1 << forw_packet_aggr
->num_packets
);
158 void add_bat_packet_to_list(unsigned char *packet_buff
, int packet_len
,
159 struct batman_if
*if_incoming
, char own_packet
,
160 unsigned long send_time
)
163 * _aggr -> pointer to the packet we want to aggregate with
164 * _pos -> pointer to the position in the queue
166 struct forw_packet
*forw_packet_aggr
= NULL
, *forw_packet_pos
= NULL
;
167 struct hlist_node
*tmp_node
;
168 struct batman_packet
*batman_packet
=
169 (struct batman_packet
*)packet_buff
;
170 bool direct_link
= batman_packet
->flags
& DIRECTLINK
? 1 : 0;
172 /* find position for the packet in the forward queue */
173 spin_lock(&forw_bat_list_lock
);
174 /* own packets are not to be aggregated */
175 if ((atomic_read(&aggregation_enabled
)) && (!own_packet
)) {
176 hlist_for_each_entry(forw_packet_pos
, tmp_node
, &forw_bat_list
,
178 if (can_aggregate_with(batman_packet
,
184 forw_packet_aggr
= forw_packet_pos
;
190 /* nothing to aggregate with - either aggregation disabled or no
191 * suitable aggregation packet found */
192 if (forw_packet_aggr
== NULL
) {
193 /* the following section can run without the lock */
194 spin_unlock(&forw_bat_list_lock
);
195 new_aggregated_packet(packet_buff
, packet_len
,
196 send_time
, direct_link
,
197 if_incoming
, own_packet
);
199 aggregate(forw_packet_aggr
,
200 packet_buff
, packet_len
,
202 spin_unlock(&forw_bat_list_lock
);
206 /* unpack the aggregated packets and process them one by one */
207 void receive_aggr_bat_packet(struct ethhdr
*ethhdr
, unsigned char *packet_buff
,
208 int packet_len
, struct batman_if
*if_incoming
)
210 struct batman_packet
*batman_packet
;
212 unsigned char *hna_buff
;
214 batman_packet
= (struct batman_packet
*)packet_buff
;
216 while (aggregated_packet(buff_pos
, packet_len
,
217 batman_packet
->num_hna
)) {
219 /* network to host order for our 16bit seqno, and the
221 batman_packet
->seqno
= ntohs(batman_packet
->seqno
);
223 hna_buff
= packet_buff
+ buff_pos
+ BAT_PACKET_LEN
;
224 receive_bat_packet(ethhdr
, batman_packet
,
225 hna_buff
, hna_len(batman_packet
),
228 buff_pos
+= BAT_PACKET_LEN
+ hna_len(batman_packet
);
229 batman_packet
= (struct batman_packet
*)
230 (packet_buff
+ buff_pos
);