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authorDavid S. Miller <davem@davemloft.net>2010-11-11 13:43:30 -0500
committerDavid S. Miller <davem@davemloft.net>2010-11-11 13:43:30 -0500
commited1deb7021b4dfee1d544b91edff4ef92f5c3b54 (patch)
treed4bfb7f1ec0e74db6d4f05245f56ccbc3a1173bf /net
parent72cdd1d971c0deb1619c5c339270570c43647a78 (diff)
parentb3d14bff12a38ad13a174eb0cc83d2ac7169eee4 (diff)
Merge branch 'dccp' of git://eden-feed.erg.abdn.ac.uk/net-next-2.6
Diffstat (limited to 'net')
-rw-r--r--net/dccp/ackvec.c251
-rw-r--r--net/dccp/ackvec.h115
-rw-r--r--net/dccp/ccids/ccid2.c13
-rw-r--r--net/dccp/dccp.h11
-rw-r--r--net/dccp/input.c6
-rw-r--r--net/dccp/options.c65
6 files changed, 225 insertions, 236 deletions
diff --git a/net/dccp/ackvec.c b/net/dccp/ackvec.c
index 92a6fcb40d7d..abaf241c7353 100644
--- a/net/dccp/ackvec.c
+++ b/net/dccp/ackvec.c
@@ -1,7 +1,8 @@
1/* 1/*
2 * net/dccp/ackvec.c 2 * net/dccp/ackvec.c
3 * 3 *
4 * An implementation of the DCCP protocol 4 * An implementation of Ack Vectors for the DCCP protocol
5 * Copyright (c) 2007 University of Aberdeen, Scotland, UK
5 * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net> 6 * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
6 * 7 *
7 * This program is free software; you can redistribute it and/or modify it 8 * This program is free software; you can redistribute it and/or modify it
@@ -23,173 +24,93 @@
23static struct kmem_cache *dccp_ackvec_slab; 24static struct kmem_cache *dccp_ackvec_slab;
24static struct kmem_cache *dccp_ackvec_record_slab; 25static struct kmem_cache *dccp_ackvec_record_slab;
25 26
26static struct dccp_ackvec_record *dccp_ackvec_record_new(void) 27struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
27{ 28{
28 struct dccp_ackvec_record *avr = 29 struct dccp_ackvec *av = kmem_cache_zalloc(dccp_ackvec_slab, priority);
29 kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);
30
31 if (avr != NULL)
32 INIT_LIST_HEAD(&avr->avr_node);
33 30
34 return avr; 31 if (av != NULL) {
32 av->av_buf_head = av->av_buf_tail = DCCPAV_MAX_ACKVEC_LEN - 1;
33 INIT_LIST_HEAD(&av->av_records);
34 }
35 return av;
35} 36}
36 37
37static void dccp_ackvec_record_delete(struct dccp_ackvec_record *avr) 38static void dccp_ackvec_purge_records(struct dccp_ackvec *av)
38{ 39{
39 if (unlikely(avr == NULL)) 40 struct dccp_ackvec_record *cur, *next;
40 return; 41
41 /* Check if deleting a linked record */ 42 list_for_each_entry_safe(cur, next, &av->av_records, avr_node)
42 WARN_ON(!list_empty(&avr->avr_node)); 43 kmem_cache_free(dccp_ackvec_record_slab, cur);
43 kmem_cache_free(dccp_ackvec_record_slab, avr); 44 INIT_LIST_HEAD(&av->av_records);
44} 45}
45 46
46static void dccp_ackvec_insert_avr(struct dccp_ackvec *av, 47void dccp_ackvec_free(struct dccp_ackvec *av)
47 struct dccp_ackvec_record *avr)
48{ 48{
49 /* 49 if (likely(av != NULL)) {
50 * AVRs are sorted by seqno. Since we are sending them in order, we 50 dccp_ackvec_purge_records(av);
51 * just add the AVR at the head of the list. 51 kmem_cache_free(dccp_ackvec_slab, av);
52 * -sorbo.
53 */
54 if (!list_empty(&av->av_records)) {
55 const struct dccp_ackvec_record *head =
56 list_entry(av->av_records.next,
57 struct dccp_ackvec_record,
58 avr_node);
59 BUG_ON(before48(avr->avr_ack_seqno, head->avr_ack_seqno));
60 } 52 }
61
62 list_add(&avr->avr_node, &av->av_records);
63} 53}
64 54
65int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb) 55/**
56 * dccp_ackvec_update_records - Record information about sent Ack Vectors
57 * @av: Ack Vector records to update
58 * @seqno: Sequence number of the packet carrying the Ack Vector just sent
59 * @nonce_sum: The sum of all buffer nonces contained in the Ack Vector
60 */
61int dccp_ackvec_update_records(struct dccp_ackvec *av, u64 seqno, u8 nonce_sum)
66{ 62{
67 struct dccp_sock *dp = dccp_sk(sk);
68 struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
69 /* Figure out how many options do we need to represent the ackvec */
70 const u8 nr_opts = DIV_ROUND_UP(av->av_vec_len, DCCP_SINGLE_OPT_MAXLEN);
71 u16 len = av->av_vec_len + 2 * nr_opts, i;
72 u32 elapsed_time;
73 const unsigned char *tail, *from;
74 unsigned char *to;
75 struct dccp_ackvec_record *avr; 63 struct dccp_ackvec_record *avr;
76 suseconds_t delta;
77
78 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
79 return -1;
80
81 delta = ktime_us_delta(ktime_get_real(), av->av_time);
82 elapsed_time = delta / 10;
83 64
84 if (elapsed_time != 0 && 65 avr = kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);
85 dccp_insert_option_elapsed_time(skb, elapsed_time))
86 return -1;
87
88 avr = dccp_ackvec_record_new();
89 if (avr == NULL) 66 if (avr == NULL)
90 return -1; 67 return -ENOBUFS;
91
92 DCCP_SKB_CB(skb)->dccpd_opt_len += len;
93
94 to = skb_push(skb, len);
95 len = av->av_vec_len;
96 from = av->av_buf + av->av_buf_head;
97 tail = av->av_buf + DCCP_MAX_ACKVEC_LEN;
98
99 for (i = 0; i < nr_opts; ++i) {
100 int copylen = len;
101
102 if (len > DCCP_SINGLE_OPT_MAXLEN)
103 copylen = DCCP_SINGLE_OPT_MAXLEN;
104
105 *to++ = DCCPO_ACK_VECTOR_0;
106 *to++ = copylen + 2;
107
108 /* Check if buf_head wraps */
109 if (from + copylen > tail) {
110 const u16 tailsize = tail - from;
111
112 memcpy(to, from, tailsize);
113 to += tailsize;
114 len -= tailsize;
115 copylen -= tailsize;
116 from = av->av_buf;
117 }
118
119 memcpy(to, from, copylen);
120 from += copylen;
121 to += copylen;
122 len -= copylen;
123 }
124 68
69 avr->avr_ack_seqno = seqno;
70 avr->avr_ack_ptr = av->av_buf_head;
71 avr->avr_ack_ackno = av->av_buf_ackno;
72 avr->avr_ack_nonce = nonce_sum;
73 avr->avr_ack_runlen = dccp_ackvec_runlen(av->av_buf + av->av_buf_head);
125 /* 74 /*
126 * From RFC 4340, A.2: 75 * When the buffer overflows, we keep no more than one record. This is
127 * 76 * the simplest way of disambiguating sender-Acks dating from before the
128 * For each acknowledgement it sends, the HC-Receiver will add an 77 * overflow from sender-Acks which refer to after the overflow; a simple
129 * acknowledgement record. ack_seqno will equal the HC-Receiver 78 * solution is preferable here since we are handling an exception.
130 * sequence number it used for the ack packet; ack_ptr will equal
131 * buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
132 * equal buf_nonce.
133 */ 79 */
134 avr->avr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq; 80 if (av->av_overflow)
135 avr->avr_ack_ptr = av->av_buf_head; 81 dccp_ackvec_purge_records(av);
136 avr->avr_ack_ackno = av->av_buf_ackno; 82 /*
137 avr->avr_ack_nonce = av->av_buf_nonce; 83 * Since GSS is incremented for each packet, the list is automatically
138 avr->avr_sent_len = av->av_vec_len; 84 * arranged in descending order of @ack_seqno.
139 85 */
140 dccp_ackvec_insert_avr(av, avr); 86 list_add(&avr->avr_node, &av->av_records);
141 87
142 dccp_pr_debug("%s ACK Vector 0, len=%d, ack_seqno=%llu, " 88 dccp_pr_debug("Added Vector, ack_seqno=%llu, ack_ackno=%llu (rl=%u)\n",
143 "ack_ackno=%llu\n",
144 dccp_role(sk), avr->avr_sent_len,
145 (unsigned long long)avr->avr_ack_seqno, 89 (unsigned long long)avr->avr_ack_seqno,
146 (unsigned long long)avr->avr_ack_ackno); 90 (unsigned long long)avr->avr_ack_ackno,
91 avr->avr_ack_runlen);
147 return 0; 92 return 0;
148} 93}
149 94
150struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority) 95/*
151{ 96 * Buffer index and length computation using modulo-buffersize arithmetic.
152 struct dccp_ackvec *av = kmem_cache_alloc(dccp_ackvec_slab, priority); 97 * Note that, as pointers move from right to left, head is `before' tail.
153 98 */
154 if (av != NULL) { 99static inline u16 __ackvec_idx_add(const u16 a, const u16 b)
155 av->av_buf_head = DCCP_MAX_ACKVEC_LEN - 1;
156 av->av_buf_ackno = UINT48_MAX + 1;
157 av->av_buf_nonce = 0;
158 av->av_time = ktime_set(0, 0);
159 av->av_vec_len = 0;
160 INIT_LIST_HEAD(&av->av_records);
161 }
162
163 return av;
164}
165
166void dccp_ackvec_free(struct dccp_ackvec *av)
167{ 100{
168 if (unlikely(av == NULL)) 101 return (a + b) % DCCPAV_MAX_ACKVEC_LEN;
169 return;
170
171 if (!list_empty(&av->av_records)) {
172 struct dccp_ackvec_record *avr, *next;
173
174 list_for_each_entry_safe(avr, next, &av->av_records, avr_node) {
175 list_del_init(&avr->avr_node);
176 dccp_ackvec_record_delete(avr);
177 }
178 }
179
180 kmem_cache_free(dccp_ackvec_slab, av);
181} 102}
182 103
183static inline u8 dccp_ackvec_state(const struct dccp_ackvec *av, 104static inline u16 __ackvec_idx_sub(const u16 a, const u16 b)
184 const u32 index)
185{ 105{
186 return av->av_buf[index] & DCCP_ACKVEC_STATE_MASK; 106 return __ackvec_idx_add(a, DCCPAV_MAX_ACKVEC_LEN - b);
187} 107}
188 108
189static inline u8 dccp_ackvec_len(const struct dccp_ackvec *av, 109u16 dccp_ackvec_buflen(const struct dccp_ackvec *av)
190 const u32 index)
191{ 110{
192 return av->av_buf[index] & DCCP_ACKVEC_LEN_MASK; 111 if (unlikely(av->av_overflow))
112 return DCCPAV_MAX_ACKVEC_LEN;
113 return __ackvec_idx_sub(av->av_buf_tail, av->av_buf_head);
193} 114}
194 115
195/* 116/*
@@ -204,7 +125,7 @@ static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av,
204 long gap; 125 long gap;
205 long new_head; 126 long new_head;
206 127
207 if (av->av_vec_len + packets > DCCP_MAX_ACKVEC_LEN) 128 if (av->av_vec_len + packets > DCCPAV_MAX_ACKVEC_LEN)
208 return -ENOBUFS; 129 return -ENOBUFS;
209 130
210 gap = packets - 1; 131 gap = packets - 1;
@@ -212,18 +133,18 @@ static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av,
212 133
213 if (new_head < 0) { 134 if (new_head < 0) {
214 if (gap > 0) { 135 if (gap > 0) {
215 memset(av->av_buf, DCCP_ACKVEC_STATE_NOT_RECEIVED, 136 memset(av->av_buf, DCCPAV_NOT_RECEIVED,
216 gap + new_head + 1); 137 gap + new_head + 1);
217 gap = -new_head; 138 gap = -new_head;
218 } 139 }
219 new_head += DCCP_MAX_ACKVEC_LEN; 140 new_head += DCCPAV_MAX_ACKVEC_LEN;
220 } 141 }
221 142
222 av->av_buf_head = new_head; 143 av->av_buf_head = new_head;
223 144
224 if (gap > 0) 145 if (gap > 0)
225 memset(av->av_buf + av->av_buf_head + 1, 146 memset(av->av_buf + av->av_buf_head + 1,
226 DCCP_ACKVEC_STATE_NOT_RECEIVED, gap); 147 DCCPAV_NOT_RECEIVED, gap);
227 148
228 av->av_buf[av->av_buf_head] = state; 149 av->av_buf[av->av_buf_head] = state;
229 av->av_vec_len += packets; 150 av->av_vec_len += packets;
@@ -236,6 +157,8 @@ static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av,
236int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk, 157int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
237 const u64 ackno, const u8 state) 158 const u64 ackno, const u8 state)
238{ 159{
160 u8 *cur_head = av->av_buf + av->av_buf_head,
161 *buf_end = av->av_buf + DCCPAV_MAX_ACKVEC_LEN;
239 /* 162 /*
240 * Check at the right places if the buffer is full, if it is, tell the 163 * Check at the right places if the buffer is full, if it is, tell the
241 * caller to start dropping packets till the HC-Sender acks our ACK 164 * caller to start dropping packets till the HC-Sender acks our ACK
@@ -260,7 +183,7 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
260 183
261 /* See if this is the first ackno being inserted */ 184 /* See if this is the first ackno being inserted */
262 if (av->av_vec_len == 0) { 185 if (av->av_vec_len == 0) {
263 av->av_buf[av->av_buf_head] = state; 186 *cur_head = state;
264 av->av_vec_len = 1; 187 av->av_vec_len = 1;
265 } else if (after48(ackno, av->av_buf_ackno)) { 188 } else if (after48(ackno, av->av_buf_ackno)) {
266 const u64 delta = dccp_delta_seqno(av->av_buf_ackno, ackno); 189 const u64 delta = dccp_delta_seqno(av->av_buf_ackno, ackno);
@@ -269,10 +192,9 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
269 * Look if the state of this packet is the same as the 192 * Look if the state of this packet is the same as the
270 * previous ackno and if so if we can bump the head len. 193 * previous ackno and if so if we can bump the head len.
271 */ 194 */
272 if (delta == 1 && 195 if (delta == 1 && dccp_ackvec_state(cur_head) == state &&
273 dccp_ackvec_state(av, av->av_buf_head) == state && 196 dccp_ackvec_runlen(cur_head) < DCCPAV_MAX_RUNLEN)
274 dccp_ackvec_len(av, av->av_buf_head) < DCCP_ACKVEC_LEN_MASK) 197 *cur_head += 1;
275 av->av_buf[av->av_buf_head]++;
276 else if (dccp_ackvec_set_buf_head_state(av, delta, state)) 198 else if (dccp_ackvec_set_buf_head_state(av, delta, state))
277 return -ENOBUFS; 199 return -ENOBUFS;
278 } else { 200 } else {
@@ -285,21 +207,17 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
285 * could reduce the complexity of this scan.) 207 * could reduce the complexity of this scan.)
286 */ 208 */
287 u64 delta = dccp_delta_seqno(ackno, av->av_buf_ackno); 209 u64 delta = dccp_delta_seqno(ackno, av->av_buf_ackno);
288 u32 index = av->av_buf_head;
289 210
290 while (1) { 211 while (1) {
291 const u8 len = dccp_ackvec_len(av, index); 212 const u8 len = dccp_ackvec_runlen(cur_head);
292 const u8 av_state = dccp_ackvec_state(av, index);
293 /* 213 /*
294 * valid packets not yet in av_buf have a reserved 214 * valid packets not yet in av_buf have a reserved
295 * entry, with a len equal to 0. 215 * entry, with a len equal to 0.
296 */ 216 */
297 if (av_state == DCCP_ACKVEC_STATE_NOT_RECEIVED && 217 if (*cur_head == DCCPAV_NOT_RECEIVED && delta == 0) {
298 len == 0 && delta == 0) { /* Found our
299 reserved seat! */
300 dccp_pr_debug("Found %llu reserved seat!\n", 218 dccp_pr_debug("Found %llu reserved seat!\n",
301 (unsigned long long)ackno); 219 (unsigned long long)ackno);
302 av->av_buf[index] = state; 220 *cur_head = state;
303 goto out; 221 goto out;
304 } 222 }
305 /* len == 0 means one packet */ 223 /* len == 0 means one packet */
@@ -307,13 +225,12 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
307 goto out_duplicate; 225 goto out_duplicate;
308 226
309 delta -= len + 1; 227 delta -= len + 1;
310 if (++index == DCCP_MAX_ACKVEC_LEN) 228 if (++cur_head == buf_end)
311 index = 0; 229 cur_head = av->av_buf;
312 } 230 }
313 } 231 }
314 232
315 av->av_buf_ackno = ackno; 233 av->av_buf_ackno = ackno;
316 av->av_time = ktime_get_real();
317out: 234out:
318 return 0; 235 return 0;
319 236
@@ -333,13 +250,13 @@ static void dccp_ackvec_throw_record(struct dccp_ackvec *av,
333 if (av->av_buf_head <= avr->avr_ack_ptr) 250 if (av->av_buf_head <= avr->avr_ack_ptr)
334 av->av_vec_len = avr->avr_ack_ptr - av->av_buf_head; 251 av->av_vec_len = avr->avr_ack_ptr - av->av_buf_head;
335 else 252 else
336 av->av_vec_len = DCCP_MAX_ACKVEC_LEN - 1 - 253 av->av_vec_len = DCCPAV_MAX_ACKVEC_LEN - 1 -
337 av->av_buf_head + avr->avr_ack_ptr; 254 av->av_buf_head + avr->avr_ack_ptr;
338 255
339 /* free records */ 256 /* free records */
340 list_for_each_entry_safe_from(avr, next, &av->av_records, avr_node) { 257 list_for_each_entry_safe_from(avr, next, &av->av_records, avr_node) {
341 list_del_init(&avr->avr_node); 258 list_del(&avr->avr_node);
342 dccp_ackvec_record_delete(avr); 259 kmem_cache_free(dccp_ackvec_record_slab, avr);
343 } 260 }
344} 261}
345 262
@@ -357,7 +274,7 @@ void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, struct sock *sk,
357 if (ackno == avr->avr_ack_seqno) { 274 if (ackno == avr->avr_ack_seqno) {
358 dccp_pr_debug("%s ACK packet 0, len=%d, ack_seqno=%llu, " 275 dccp_pr_debug("%s ACK packet 0, len=%d, ack_seqno=%llu, "
359 "ack_ackno=%llu, ACKED!\n", 276 "ack_ackno=%llu, ACKED!\n",
360 dccp_role(sk), 1, 277 dccp_role(sk), avr->avr_ack_runlen,
361 (unsigned long long)avr->avr_ack_seqno, 278 (unsigned long long)avr->avr_ack_seqno,
362 (unsigned long long)avr->avr_ack_ackno); 279 (unsigned long long)avr->avr_ack_ackno);
363 dccp_ackvec_throw_record(av, avr); 280 dccp_ackvec_throw_record(av, avr);
@@ -387,7 +304,7 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
387 */ 304 */
388 avr = list_entry(av->av_records.next, struct dccp_ackvec_record, avr_node); 305 avr = list_entry(av->av_records.next, struct dccp_ackvec_record, avr_node);
389 while (i--) { 306 while (i--) {
390 const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK; 307 const u8 rl = dccp_ackvec_runlen(vector);
391 u64 ackno_end_rl; 308 u64 ackno_end_rl;
392 309
393 dccp_set_seqno(&ackno_end_rl, *ackno - rl); 310 dccp_set_seqno(&ackno_end_rl, *ackno - rl);
@@ -404,8 +321,7 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
404 break; 321 break;
405found: 322found:
406 if (between48(avr->avr_ack_seqno, ackno_end_rl, *ackno)) { 323 if (between48(avr->avr_ack_seqno, ackno_end_rl, *ackno)) {
407 const u8 state = *vector & DCCP_ACKVEC_STATE_MASK; 324 if (dccp_ackvec_state(vector) != DCCPAV_NOT_RECEIVED) {
408 if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) {
409 dccp_pr_debug("%s ACK vector 0, len=%d, " 325 dccp_pr_debug("%s ACK vector 0, len=%d, "
410 "ack_seqno=%llu, ack_ackno=%llu, " 326 "ack_seqno=%llu, ack_ackno=%llu, "
411 "ACKED!\n", 327 "ACKED!\n",
@@ -448,10 +364,9 @@ int __init dccp_ackvec_init(void)
448 if (dccp_ackvec_slab == NULL) 364 if (dccp_ackvec_slab == NULL)
449 goto out_err; 365 goto out_err;
450 366
451 dccp_ackvec_record_slab = 367 dccp_ackvec_record_slab = kmem_cache_create("dccp_ackvec_record",
452 kmem_cache_create("dccp_ackvec_record", 368 sizeof(struct dccp_ackvec_record),
453 sizeof(struct dccp_ackvec_record), 369 0, SLAB_HWCACHE_ALIGN, NULL);
454 0, SLAB_HWCACHE_ALIGN, NULL);
455 if (dccp_ackvec_record_slab == NULL) 370 if (dccp_ackvec_record_slab == NULL)
456 goto out_destroy_slab; 371 goto out_destroy_slab;
457 372
diff --git a/net/dccp/ackvec.h b/net/dccp/ackvec.h
index 7ea557b7c6b1..23880be8fc29 100644
--- a/net/dccp/ackvec.h
+++ b/net/dccp/ackvec.h
@@ -3,9 +3,9 @@
3/* 3/*
4 * net/dccp/ackvec.h 4 * net/dccp/ackvec.h
5 * 5 *
6 * An implementation of the DCCP protocol 6 * An implementation of Ack Vectors for the DCCP protocol
7 * Copyright (c) 2007 University of Aberdeen, Scotland, UK
7 * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@mandriva.com> 8 * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@mandriva.com>
8 *
9 * This program is free software; you can redistribute it and/or modify it 9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License version 2 as 10 * under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation. 11 * published by the Free Software Foundation.
@@ -13,75 +13,89 @@
13 13
14#include <linux/dccp.h> 14#include <linux/dccp.h>
15#include <linux/compiler.h> 15#include <linux/compiler.h>
16#include <linux/ktime.h>
17#include <linux/list.h> 16#include <linux/list.h>
18#include <linux/types.h> 17#include <linux/types.h>
19 18
20/* We can spread an ack vector across multiple options */ 19/*
21#define DCCP_MAX_ACKVEC_LEN (DCCP_SINGLE_OPT_MAXLEN * 2) 20 * Ack Vector buffer space is static, in multiples of %DCCP_SINGLE_OPT_MAXLEN,
21 * the maximum size of a single Ack Vector. Setting %DCCPAV_NUM_ACKVECS to 1
22 * will be sufficient for most cases of low Ack Ratios, using a value of 2 gives
23 * more headroom if Ack Ratio is higher or when the sender acknowledges slowly.
24 * The maximum value is bounded by the u16 types for indices and functions.
25 */
26#define DCCPAV_NUM_ACKVECS 2
27#define DCCPAV_MAX_ACKVEC_LEN (DCCP_SINGLE_OPT_MAXLEN * DCCPAV_NUM_ACKVECS)
22 28
23/* Estimated minimum average Ack Vector length - used for updating MPS */ 29/* Estimated minimum average Ack Vector length - used for updating MPS */
24#define DCCPAV_MIN_OPTLEN 16 30#define DCCPAV_MIN_OPTLEN 16
25 31
26#define DCCP_ACKVEC_STATE_RECEIVED 0 32enum dccp_ackvec_states {
27#define DCCP_ACKVEC_STATE_ECN_MARKED (1 << 6) 33 DCCPAV_RECEIVED = 0x00,
28#define DCCP_ACKVEC_STATE_NOT_RECEIVED (3 << 6) 34 DCCPAV_ECN_MARKED = 0x40,
35 DCCPAV_RESERVED = 0x80,
36 DCCPAV_NOT_RECEIVED = 0xC0
37};
38#define DCCPAV_MAX_RUNLEN 0x3F
29 39
30#define DCCP_ACKVEC_STATE_MASK 0xC0 /* 11000000 */ 40static inline u8 dccp_ackvec_runlen(const u8 *cell)
31#define DCCP_ACKVEC_LEN_MASK 0x3F /* 00111111 */ 41{
42 return *cell & DCCPAV_MAX_RUNLEN;
43}
32 44
33/** struct dccp_ackvec - ack vector 45static inline u8 dccp_ackvec_state(const u8 *cell)
34 * 46{
35 * This data structure is the one defined in RFC 4340, Appendix A. 47 return *cell & ~DCCPAV_MAX_RUNLEN;
36 * 48}
37 * @av_buf_head - circular buffer head 49
38 * @av_buf_tail - circular buffer tail 50/** struct dccp_ackvec - Ack Vector main data structure
39 * @av_buf_ackno - ack # of the most recent packet acknowledgeable in the
40 * buffer (i.e. %av_buf_head)
41 * @av_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
42 * by the buffer with State 0
43 *
44 * Additionally, the HC-Receiver must keep some information about the
45 * Ack Vectors it has recently sent. For each packet sent carrying an
46 * Ack Vector, it remembers four variables:
47 * 51 *
48 * @av_records - list of dccp_ackvec_record 52 * This implements a fixed-size circular buffer within an array and is largely
49 * @av_ack_nonce - the one-bit sum of the ECN Nonces for all State 0. 53 * based on Appendix A of RFC 4340.
50 * 54 *
51 * @av_time - the time in usecs 55 * @av_buf: circular buffer storage area
52 * @av_buf - circular buffer of acknowledgeable packets 56 * @av_buf_head: head index; begin of live portion in @av_buf
57 * @av_buf_tail: tail index; first index _after_ the live portion in @av_buf
58 * @av_buf_ackno: highest seqno of acknowledgeable packet recorded in @av_buf
59 * @av_tail_ackno: lowest seqno of acknowledgeable packet recorded in @av_buf
60 * @av_buf_nonce: ECN nonce sums, each covering subsequent segments of up to
61 * %DCCP_SINGLE_OPT_MAXLEN cells in the live portion of @av_buf
62 * @av_overflow: if 1 then buf_head == buf_tail indicates buffer wraparound
63 * @av_records: list of %dccp_ackvec_record (Ack Vectors sent previously)
64 * @av_veclen: length of the live portion of @av_buf
53 */ 65 */
54struct dccp_ackvec { 66struct dccp_ackvec {
55 u64 av_buf_ackno; 67 u8 av_buf[DCCPAV_MAX_ACKVEC_LEN];
56 struct list_head av_records;
57 ktime_t av_time;
58 u16 av_buf_head; 68 u16 av_buf_head;
69 u16 av_buf_tail;
70 u64 av_buf_ackno:48;
71 u64 av_tail_ackno:48;
72 bool av_buf_nonce[DCCPAV_NUM_ACKVECS];
73 u8 av_overflow:1;
74 struct list_head av_records;
59 u16 av_vec_len; 75 u16 av_vec_len;
60 u8 av_buf_nonce;
61 u8 av_ack_nonce;
62 u8 av_buf[DCCP_MAX_ACKVEC_LEN];
63}; 76};
64 77
65/** struct dccp_ackvec_record - ack vector record 78/** struct dccp_ackvec_record - Records information about sent Ack Vectors
66 * 79 *
67 * ACK vector record as defined in Appendix A of spec. 80 * These list entries define the additional information which the HC-Receiver
81 * keeps about recently-sent Ack Vectors; again refer to RFC 4340, Appendix A.
68 * 82 *
69 * The list is sorted by avr_ack_seqno 83 * @avr_node: the list node in @av_records
84 * @avr_ack_seqno: sequence number of the packet the Ack Vector was sent on
85 * @avr_ack_ackno: the Ack number that this record/Ack Vector refers to
86 * @avr_ack_ptr: pointer into @av_buf where this record starts
87 * @avr_ack_runlen: run length of @avr_ack_ptr at the time of sending
88 * @avr_ack_nonce: the sum of @av_buf_nonce's at the time this record was sent
70 * 89 *
71 * @avr_node - node in av_records 90 * The list as a whole is sorted in descending order by @avr_ack_seqno.
72 * @avr_ack_seqno - sequence number of the packet this record was sent on
73 * @avr_ack_ackno - sequence number being acknowledged
74 * @avr_ack_ptr - pointer into av_buf where this record starts
75 * @avr_ack_nonce - av_ack_nonce at the time this record was sent
76 * @avr_sent_len - lenght of the record in av_buf
77 */ 91 */
78struct dccp_ackvec_record { 92struct dccp_ackvec_record {
79 struct list_head avr_node; 93 struct list_head avr_node;
80 u64 avr_ack_seqno; 94 u64 avr_ack_seqno:48;
81 u64 avr_ack_ackno; 95 u64 avr_ack_ackno:48;
82 u16 avr_ack_ptr; 96 u16 avr_ack_ptr;
83 u16 avr_sent_len; 97 u8 avr_ack_runlen;
84 u8 avr_ack_nonce; 98 u8 avr_ack_nonce:1;
85}; 99};
86 100
87struct sock; 101struct sock;
@@ -102,10 +116,11 @@ extern int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
102 u64 *ackno, const u8 opt, 116 u64 *ackno, const u8 opt,
103 const u8 *value, const u8 len); 117 const u8 *value, const u8 len);
104 118
105extern int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb); 119extern int dccp_ackvec_update_records(struct dccp_ackvec *av, u64 seq, u8 sum);
120extern u16 dccp_ackvec_buflen(const struct dccp_ackvec *av);
106 121
107static inline int dccp_ackvec_pending(const struct dccp_ackvec *av) 122static inline bool dccp_ackvec_is_empty(const struct dccp_ackvec *av)
108{ 123{
109 return av->av_vec_len; 124 return av->av_overflow == 0 && av->av_buf_head == av->av_buf_tail;
110} 125}
111#endif /* _ACKVEC_H */ 126#endif /* _ACKVEC_H */
diff --git a/net/dccp/ccids/ccid2.c b/net/dccp/ccids/ccid2.c
index 6576eae9e779..cb1b4a0d1877 100644
--- a/net/dccp/ccids/ccid2.c
+++ b/net/dccp/ccids/ccid2.c
@@ -513,8 +513,7 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
513 &vector, &veclen)) != -1) { 513 &vector, &veclen)) != -1) {
514 /* go through this ack vector */ 514 /* go through this ack vector */
515 while (veclen--) { 515 while (veclen--) {
516 const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK; 516 u64 ackno_end_rl = SUB48(ackno, dccp_ackvec_runlen(vector));
517 u64 ackno_end_rl = SUB48(ackno, rl);
518 517
519 ccid2_pr_debug("ackvec start:%llu end:%llu\n", 518 ccid2_pr_debug("ackvec start:%llu end:%llu\n",
520 (unsigned long long)ackno, 519 (unsigned long long)ackno,
@@ -537,17 +536,15 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
537 * run length 536 * run length
538 */ 537 */
539 while (between48(seqp->ccid2s_seq,ackno_end_rl,ackno)) { 538 while (between48(seqp->ccid2s_seq,ackno_end_rl,ackno)) {
540 const u8 state = *vector & 539 const u8 state = dccp_ackvec_state(vector);
541 DCCP_ACKVEC_STATE_MASK;
542 540
543 /* new packet received or marked */ 541 /* new packet received or marked */
544 if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED && 542 if (state != DCCPAV_NOT_RECEIVED &&
545 !seqp->ccid2s_acked) { 543 !seqp->ccid2s_acked) {
546 if (state == 544 if (state == DCCPAV_ECN_MARKED)
547 DCCP_ACKVEC_STATE_ECN_MARKED) {
548 ccid2_congestion_event(sk, 545 ccid2_congestion_event(sk,
549 seqp); 546 seqp);
550 } else 547 else
551 ccid2_new_ack(sk, seqp, 548 ccid2_new_ack(sk, seqp,
552 &maxincr); 549 &maxincr);
553 550
diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h
index a8ed459508b2..19fafd597465 100644
--- a/net/dccp/dccp.h
+++ b/net/dccp/dccp.h
@@ -457,12 +457,15 @@ static inline void dccp_update_gss(struct sock *sk, u64 seq)
457 dp->dccps_awh = dp->dccps_gss; 457 dp->dccps_awh = dp->dccps_gss;
458} 458}
459 459
460static inline int dccp_ackvec_pending(const struct sock *sk)
461{
462 return dccp_sk(sk)->dccps_hc_rx_ackvec != NULL &&
463 !dccp_ackvec_is_empty(dccp_sk(sk)->dccps_hc_rx_ackvec);
464}
465
460static inline int dccp_ack_pending(const struct sock *sk) 466static inline int dccp_ack_pending(const struct sock *sk)
461{ 467{
462 const struct dccp_sock *dp = dccp_sk(sk); 468 return dccp_ackvec_pending(sk) || inet_csk_ack_scheduled(sk);
463 return (dp->dccps_hc_rx_ackvec != NULL &&
464 dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) ||
465 inet_csk_ack_scheduled(sk);
466} 469}
467 470
468extern int dccp_feat_finalise_settings(struct dccp_sock *dp); 471extern int dccp_feat_finalise_settings(struct dccp_sock *dp);
diff --git a/net/dccp/input.c b/net/dccp/input.c
index 265985370fa1..c7aeeba859d4 100644
--- a/net/dccp/input.c
+++ b/net/dccp/input.c
@@ -378,8 +378,7 @@ int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
378 378
379 if (dp->dccps_hc_rx_ackvec != NULL && 379 if (dp->dccps_hc_rx_ackvec != NULL &&
380 dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk, 380 dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
381 DCCP_SKB_CB(skb)->dccpd_seq, 381 DCCP_SKB_CB(skb)->dccpd_seq, DCCPAV_RECEIVED))
382 DCCP_ACKVEC_STATE_RECEIVED))
383 goto discard; 382 goto discard;
384 dccp_deliver_input_to_ccids(sk, skb); 383 dccp_deliver_input_to_ccids(sk, skb);
385 384
@@ -637,8 +636,7 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
637 636
638 if (dp->dccps_hc_rx_ackvec != NULL && 637 if (dp->dccps_hc_rx_ackvec != NULL &&
639 dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk, 638 dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
640 DCCP_SKB_CB(skb)->dccpd_seq, 639 DCCP_SKB_CB(skb)->dccpd_seq, DCCPAV_RECEIVED))
641 DCCP_ACKVEC_STATE_RECEIVED))
642 goto discard; 640 goto discard;
643 641
644 dccp_deliver_input_to_ccids(sk, skb); 642 dccp_deliver_input_to_ccids(sk, skb);
diff --git a/net/dccp/options.c b/net/dccp/options.c
index cd3061813009..5adeeed5e0d2 100644
--- a/net/dccp/options.c
+++ b/net/dccp/options.c
@@ -340,6 +340,7 @@ static inline int dccp_elapsed_time_len(const u32 elapsed_time)
340 return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4; 340 return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4;
341} 341}
342 342
343/* FIXME: This function is currently not used anywhere */
343int dccp_insert_option_elapsed_time(struct sk_buff *skb, u32 elapsed_time) 344int dccp_insert_option_elapsed_time(struct sk_buff *skb, u32 elapsed_time)
344{ 345{
345 const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time); 346 const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
@@ -424,6 +425,67 @@ static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp,
424 return 0; 425 return 0;
425} 426}
426 427
428static int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
429{
430 struct dccp_sock *dp = dccp_sk(sk);
431 struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
432 const u16 buflen = dccp_ackvec_buflen(av);
433 /* Figure out how many options do we need to represent the ackvec */
434 const u8 nr_opts = DIV_ROUND_UP(buflen, DCCP_SINGLE_OPT_MAXLEN);
435 u16 len = buflen + 2 * nr_opts;
436 u8 i, nonce = 0;
437 const unsigned char *tail, *from;
438 unsigned char *to;
439
440 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
441 return -1;
442
443 DCCP_SKB_CB(skb)->dccpd_opt_len += len;
444
445 to = skb_push(skb, len);
446 len = buflen;
447 from = av->av_buf + av->av_buf_head;
448 tail = av->av_buf + DCCPAV_MAX_ACKVEC_LEN;
449
450 for (i = 0; i < nr_opts; ++i) {
451 int copylen = len;
452
453 if (len > DCCP_SINGLE_OPT_MAXLEN)
454 copylen = DCCP_SINGLE_OPT_MAXLEN;
455
456 /*
457 * RFC 4340, 12.2: Encode the Nonce Echo for this Ack Vector via
458 * its type; ack_nonce is the sum of all individual buf_nonce's.
459 */
460 nonce ^= av->av_buf_nonce[i];
461
462 *to++ = DCCPO_ACK_VECTOR_0 + av->av_buf_nonce[i];
463 *to++ = copylen + 2;
464
465 /* Check if buf_head wraps */
466 if (from + copylen > tail) {
467 const u16 tailsize = tail - from;
468
469 memcpy(to, from, tailsize);
470 to += tailsize;
471 len -= tailsize;
472 copylen -= tailsize;
473 from = av->av_buf;
474 }
475
476 memcpy(to, from, copylen);
477 from += copylen;
478 to += copylen;
479 len -= copylen;
480 }
481 /*
482 * Each sent Ack Vector is recorded in the list, as per A.2 of RFC 4340.
483 */
484 if (dccp_ackvec_update_records(av, DCCP_SKB_CB(skb)->dccpd_seq, nonce))
485 return -ENOBUFS;
486 return 0;
487}
488
427/** 489/**
428 * dccp_insert_option_mandatory - Mandatory option (5.8.2) 490 * dccp_insert_option_mandatory - Mandatory option (5.8.2)
429 * Note that since we are using skb_push, this function needs to be called 491 * Note that since we are using skb_push, this function needs to be called
@@ -519,8 +581,7 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
519 if (dccp_insert_option_timestamp(skb)) 581 if (dccp_insert_option_timestamp(skb))
520 return -1; 582 return -1;
521 583
522 } else if (dp->dccps_hc_rx_ackvec != NULL && 584 } else if (dccp_ackvec_pending(sk) &&
523 dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
524 dccp_insert_option_ackvec(sk, skb)) { 585 dccp_insert_option_ackvec(sk, skb)) {
525 return -1; 586 return -1;
526 } 587 }