1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
|
/*
* Copyright (C) 2007-2010 B.A.T.M.A.N. contributors:
*
* Marek Lindner, 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 "aggregation.h"
#include "send.h"
#include "routing.h"
/* calculate the size of the hna information for a given packet */
static int hna_len(struct batman_packet *batman_packet)
{
return batman_packet->num_hna * ETH_ALEN;
}
/* return true if new_packet can be aggregated with forw_packet */
static bool can_aggregate_with(struct batman_packet *new_batman_packet,
int packet_len,
unsigned long send_time,
bool directlink,
struct batman_if *if_incoming,
struct forw_packet *forw_packet)
{
struct batman_packet *batman_packet =
(struct batman_packet *)forw_packet->skb->data;
int aggregated_bytes = forw_packet->packet_len + packet_len;
/**
* we can aggregate the current packet to this aggregated packet
* if:
*
* - the send time is within our MAX_AGGREGATION_MS time
* - the resulting packet wont be bigger than
* MAX_AGGREGATION_BYTES
*/
if (time_before(send_time, forw_packet->send_time) &&
time_after_eq(send_time + msecs_to_jiffies(MAX_AGGREGATION_MS),
forw_packet->send_time) &&
(aggregated_bytes <= MAX_AGGREGATION_BYTES)) {
/**
* check aggregation compatibility
* -> direct link packets are broadcasted on
* their interface only
* -> aggregate packet if the current packet is
* a "global" packet as well as the base
* packet
*/
/* packets without direct link flag and high TTL
* are flooded through the net */
if ((!directlink) &&
(!(batman_packet->flags & DIRECTLINK)) &&
(batman_packet->ttl != 1) &&
/* own packets originating non-primary
* interfaces leave only that interface */
((!forw_packet->own) ||
(forw_packet->if_incoming->if_num == 0)))
return true;
/* if the incoming packet is sent via this one
* interface only - we still can aggregate */
if ((directlink) &&
(new_batman_packet->ttl == 1) &&
(forw_packet->if_incoming == if_incoming) &&
/* packets from direct neighbors or
* own secondary interface packets
* (= secondary interface packets in general) */
(batman_packet->flags & DIRECTLINK ||
(forw_packet->own &&
forw_packet->if_incoming->if_num != 0)))
return true;
}
return false;
}
#define atomic_dec_not_zero(v) atomic_add_unless((v), -1, 0)
/* create a new aggregated packet and add this packet to it */
static void new_aggregated_packet(unsigned char *packet_buff, int packet_len,
unsigned long send_time, bool direct_link,
struct batman_if *if_incoming,
int own_packet)
{
struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
struct forw_packet *forw_packet_aggr;
unsigned char *skb_buff;
/* own packet should always be scheduled */
if (!own_packet) {
if (!atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
bat_dbg(DBG_BATMAN, bat_priv,
"batman packet queue full\n");
return;
}
}
forw_packet_aggr = kmalloc(sizeof(struct forw_packet), GFP_ATOMIC);
if (!forw_packet_aggr) {
if (!own_packet)
atomic_inc(&bat_priv->batman_queue_left);
return;
}
if ((atomic_read(&bat_priv->aggregated_ogms)) &&
(packet_len < MAX_AGGREGATION_BYTES))
forw_packet_aggr->skb = dev_alloc_skb(MAX_AGGREGATION_BYTES +
sizeof(struct ethhdr));
else
forw_packet_aggr->skb = dev_alloc_skb(packet_len +
sizeof(struct ethhdr));
if (!forw_packet_aggr->skb) {
if (!own_packet)
atomic_inc(&bat_priv->batman_queue_left);
kfree(forw_packet_aggr);
return;
}
skb_reserve(forw_packet_aggr->skb, sizeof(struct ethhdr));
INIT_HLIST_NODE(&forw_packet_aggr->list);
skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
forw_packet_aggr->packet_len = packet_len;
memcpy(skb_buff, packet_buff, packet_len);
forw_packet_aggr->own = own_packet;
forw_packet_aggr->if_incoming = if_incoming;
forw_packet_aggr->num_packets = 0;
forw_packet_aggr->direct_link_flags = 0;
forw_packet_aggr->send_time = send_time;
/* save packet direct link flag status */
if (direct_link)
forw_packet_aggr->direct_link_flags |= 1;
/* add new packet to packet list */
spin_lock_bh(&bat_priv->forw_bat_list_lock);
hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
spin_unlock_bh(&bat_priv->forw_bat_list_lock);
/* start timer for this packet */
INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
send_outstanding_bat_packet);
queue_delayed_work(bat_event_workqueue,
&forw_packet_aggr->delayed_work,
send_time - jiffies);
}
/* aggregate a new packet into the existing aggregation */
static void aggregate(struct forw_packet *forw_packet_aggr,
unsigned char *packet_buff,
int packet_len,
bool direct_link)
{
unsigned char *skb_buff;
skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
memcpy(skb_buff, packet_buff, packet_len);
forw_packet_aggr->packet_len += packet_len;
forw_packet_aggr->num_packets++;
/* save packet direct link flag status */
if (direct_link)
forw_packet_aggr->direct_link_flags |=
(1 << forw_packet_aggr->num_packets);
}
void add_bat_packet_to_list(struct bat_priv *bat_priv,
unsigned char *packet_buff, int packet_len,
struct batman_if *if_incoming, char own_packet,
unsigned long send_time)
{
/**
* _aggr -> pointer to the packet we want to aggregate with
* _pos -> pointer to the position in the queue
*/
struct forw_packet *forw_packet_aggr = NULL, *forw_packet_pos = NULL;
struct hlist_node *tmp_node;
struct batman_packet *batman_packet =
(struct batman_packet *)packet_buff;
bool direct_link = batman_packet->flags & DIRECTLINK ? 1 : 0;
/* find position for the packet in the forward queue */
spin_lock_bh(&bat_priv->forw_bat_list_lock);
/* own packets are not to be aggregated */
if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
hlist_for_each_entry(forw_packet_pos, tmp_node,
&bat_priv->forw_bat_list, list) {
if (can_aggregate_with(batman_packet,
packet_len,
send_time,
direct_link,
if_incoming,
forw_packet_pos)) {
forw_packet_aggr = forw_packet_pos;
break;
}
}
}
/* nothing to aggregate with - either aggregation disabled or no
* suitable aggregation packet found */
if (!forw_packet_aggr) {
/* the following section can run without the lock */
spin_unlock_bh(&bat_priv->forw_bat_list_lock);
/**
* if we could not aggregate this packet with one of the others
* we hold it back for a while, so that it might be aggregated
* later on
*/
if ((!own_packet) &&
(atomic_read(&bat_priv->aggregated_ogms)))
send_time += msecs_to_jiffies(MAX_AGGREGATION_MS);
new_aggregated_packet(packet_buff, packet_len,
send_time, direct_link,
if_incoming, own_packet);
} else {
aggregate(forw_packet_aggr,
packet_buff, packet_len,
direct_link);
spin_unlock_bh(&bat_priv->forw_bat_list_lock);
}
}
/* unpack the aggregated packets and process them one by one */
void receive_aggr_bat_packet(struct ethhdr *ethhdr, unsigned char *packet_buff,
int packet_len, struct batman_if *if_incoming)
{
struct batman_packet *batman_packet;
int buff_pos = 0;
unsigned char *hna_buff;
batman_packet = (struct batman_packet *)packet_buff;
do {
/* network to host order for our 32bit seqno, and the
orig_interval. */
batman_packet->seqno = ntohl(batman_packet->seqno);
hna_buff = packet_buff + buff_pos + BAT_PACKET_LEN;
receive_bat_packet(ethhdr, batman_packet,
hna_buff, hna_len(batman_packet),
if_incoming);
buff_pos += BAT_PACKET_LEN + hna_len(batman_packet);
batman_packet = (struct batman_packet *)
(packet_buff + buff_pos);
} while (aggregated_packet(buff_pos, packet_len,
batman_packet->num_hna));
}
|
