Commit | Line | Data |
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ae31c339 ACM |
1 | /* |
2 | * net/dccp/ackvec.c | |
3 | * | |
4 | * An implementation of the DCCP protocol | |
5 | * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify it | |
8 | * under the terms of the GNU General Public License as published by the | |
9 | * Free Software Foundation; version 2 of the License; | |
10 | */ | |
11 | ||
12 | #include "ackvec.h" | |
13 | #include "dccp.h" | |
14 | ||
15 | #include <linux/dccp.h> | |
9b07ef5d ACM |
16 | #include <linux/init.h> |
17 | #include <linux/errno.h> | |
18 | #include <linux/kernel.h> | |
ae31c339 | 19 | #include <linux/skbuff.h> |
9b07ef5d | 20 | #include <linux/slab.h> |
ae31c339 ACM |
21 | |
22 | #include <net/sock.h> | |
23 | ||
9b07ef5d | 24 | static kmem_cache_t *dccp_ackvec_slab; |
02bcf28c AB |
25 | static kmem_cache_t *dccp_ackvec_record_slab; |
26 | ||
27 | static struct dccp_ackvec_record *dccp_ackvec_record_new(void) | |
28 | { | |
29 | struct dccp_ackvec_record *avr = | |
30 | kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC); | |
31 | ||
32 | if (avr != NULL) | |
33 | INIT_LIST_HEAD(&avr->dccpavr_node); | |
34 | ||
35 | return avr; | |
36 | } | |
37 | ||
38 | static void dccp_ackvec_record_delete(struct dccp_ackvec_record *avr) | |
39 | { | |
40 | if (unlikely(avr == NULL)) | |
41 | return; | |
42 | /* Check if deleting a linked record */ | |
43 | WARN_ON(!list_empty(&avr->dccpavr_node)); | |
44 | kmem_cache_free(dccp_ackvec_record_slab, avr); | |
45 | } | |
46 | ||
47 | static void dccp_ackvec_insert_avr(struct dccp_ackvec *av, | |
48 | struct dccp_ackvec_record *avr) | |
49 | { | |
50 | /* | |
51 | * AVRs are sorted by seqno. Since we are sending them in order, we | |
52 | * just add the AVR at the head of the list. | |
53 | * -sorbo. | |
54 | */ | |
55 | if (!list_empty(&av->dccpav_records)) { | |
56 | const struct dccp_ackvec_record *head = | |
57 | list_entry(av->dccpav_records.next, | |
58 | struct dccp_ackvec_record, | |
59 | dccpavr_node); | |
60 | BUG_ON(before48(avr->dccpavr_ack_seqno, | |
61 | head->dccpavr_ack_seqno)); | |
62 | } | |
63 | ||
64 | list_add(&avr->dccpavr_node, &av->dccpav_records); | |
65 | } | |
9b07ef5d | 66 | |
ae31c339 ACM |
67 | int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb) |
68 | { | |
69 | struct dccp_sock *dp = dccp_sk(sk); | |
7400d781 ACM |
70 | #ifdef CONFIG_IP_DCCP_DEBUG |
71 | const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ? | |
72 | "CLIENT tx: " : "server tx: "; | |
73 | #endif | |
ae31c339 ACM |
74 | struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec; |
75 | int len = av->dccpav_vec_len + 2; | |
76 | struct timeval now; | |
77 | u32 elapsed_time; | |
78 | unsigned char *to, *from; | |
02bcf28c AB |
79 | struct dccp_ackvec_record *avr; |
80 | ||
81 | if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) | |
82 | return -1; | |
83 | ||
ae31c339 ACM |
84 | dccp_timestamp(sk, &now); |
85 | elapsed_time = timeval_delta(&now, &av->dccpav_time) / 10; | |
86 | ||
2d0817d1 ACM |
87 | if (elapsed_time != 0 && |
88 | dccp_insert_option_elapsed_time(sk, skb, elapsed_time)) | |
89 | return -1; | |
90 | ||
91 | avr = dccp_ackvec_record_new(); | |
92 | if (avr == NULL) | |
93 | return -1; | |
ae31c339 | 94 | |
ae31c339 ACM |
95 | DCCP_SKB_CB(skb)->dccpd_opt_len += len; |
96 | ||
97 | to = skb_push(skb, len); | |
98 | *to++ = DCCPO_ACK_VECTOR_0; | |
99 | *to++ = len; | |
100 | ||
101 | len = av->dccpav_vec_len; | |
102 | from = av->dccpav_buf + av->dccpav_buf_head; | |
103 | ||
104 | /* Check if buf_head wraps */ | |
02bcf28c AB |
105 | if ((int)av->dccpav_buf_head + len > DCCP_MAX_ACKVEC_LEN) { |
106 | const u32 tailsize = DCCP_MAX_ACKVEC_LEN - av->dccpav_buf_head; | |
ae31c339 ACM |
107 | |
108 | memcpy(to, from, tailsize); | |
109 | to += tailsize; | |
110 | len -= tailsize; | |
111 | from = av->dccpav_buf; | |
112 | } | |
113 | ||
114 | memcpy(to, from, len); | |
115 | /* | |
116 | * From draft-ietf-dccp-spec-11.txt: | |
117 | * | |
118 | * For each acknowledgement it sends, the HC-Receiver will add an | |
119 | * acknowledgement record. ack_seqno will equal the HC-Receiver | |
120 | * sequence number it used for the ack packet; ack_ptr will equal | |
121 | * buf_head; ack_ackno will equal buf_ackno; and ack_nonce will | |
122 | * equal buf_nonce. | |
ae31c339 | 123 | */ |
02bcf28c AB |
124 | avr->dccpavr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq; |
125 | avr->dccpavr_ack_ptr = av->dccpav_buf_head; | |
126 | avr->dccpavr_ack_ackno = av->dccpav_buf_ackno; | |
127 | avr->dccpavr_ack_nonce = av->dccpav_buf_nonce; | |
128 | avr->dccpavr_sent_len = av->dccpav_vec_len; | |
129 | ||
130 | dccp_ackvec_insert_avr(av, avr); | |
ae31c339 ACM |
131 | |
132 | dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, " | |
133 | "ack_ackno=%llu\n", | |
02bcf28c AB |
134 | debug_prefix, avr->dccpavr_sent_len, |
135 | (unsigned long long)avr->dccpavr_ack_seqno, | |
136 | (unsigned long long)avr->dccpavr_ack_ackno); | |
137 | return 0; | |
ae31c339 ACM |
138 | } |
139 | ||
7400d781 | 140 | struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority) |
ae31c339 | 141 | { |
9b07ef5d | 142 | struct dccp_ackvec *av = kmem_cache_alloc(dccp_ackvec_slab, priority); |
e4dfd449 | 143 | |
ae31c339 | 144 | if (av != NULL) { |
ae31c339 | 145 | av->dccpav_buf_head = |
7400d781 | 146 | av->dccpav_buf_tail = DCCP_MAX_ACKVEC_LEN - 1; |
02bcf28c | 147 | av->dccpav_buf_ackno = DCCP_MAX_SEQNO + 1; |
ae31c339 ACM |
148 | av->dccpav_buf_nonce = av->dccpav_buf_nonce = 0; |
149 | av->dccpav_ack_ptr = 0; | |
150 | av->dccpav_time.tv_sec = 0; | |
151 | av->dccpav_time.tv_usec = 0; | |
152 | av->dccpav_sent_len = av->dccpav_vec_len = 0; | |
02bcf28c | 153 | INIT_LIST_HEAD(&av->dccpav_records); |
ae31c339 ACM |
154 | } |
155 | ||
156 | return av; | |
157 | } | |
158 | ||
159 | void dccp_ackvec_free(struct dccp_ackvec *av) | |
160 | { | |
02bcf28c AB |
161 | if (unlikely(av == NULL)) |
162 | return; | |
d5e9b2c7 ACM |
163 | |
164 | if (!list_empty(&av->dccpav_records)) { | |
165 | struct dccp_ackvec_record *avr, *next; | |
166 | ||
167 | list_for_each_entry_safe(avr, next, &av->dccpav_records, | |
168 | dccpavr_node) { | |
169 | list_del_init(&avr->dccpavr_node); | |
170 | dccp_ackvec_record_delete(avr); | |
171 | } | |
172 | } | |
173 | ||
9b07ef5d | 174 | kmem_cache_free(dccp_ackvec_slab, av); |
ae31c339 ACM |
175 | } |
176 | ||
177 | static inline u8 dccp_ackvec_state(const struct dccp_ackvec *av, | |
e4dfd449 | 178 | const u8 index) |
ae31c339 ACM |
179 | { |
180 | return av->dccpav_buf[index] & DCCP_ACKVEC_STATE_MASK; | |
181 | } | |
182 | ||
183 | static inline u8 dccp_ackvec_len(const struct dccp_ackvec *av, | |
e4dfd449 | 184 | const u8 index) |
ae31c339 ACM |
185 | { |
186 | return av->dccpav_buf[index] & DCCP_ACKVEC_LEN_MASK; | |
187 | } | |
188 | ||
189 | /* | |
190 | * If several packets are missing, the HC-Receiver may prefer to enter multiple | |
191 | * bytes with run length 0, rather than a single byte with a larger run length; | |
192 | * this simplifies table updates if one of the missing packets arrives. | |
193 | */ | |
194 | static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av, | |
195 | const unsigned int packets, | |
e4dfd449 | 196 | const unsigned char state) |
ae31c339 ACM |
197 | { |
198 | unsigned int gap; | |
a8fc3d8d | 199 | long new_head; |
ae31c339 | 200 | |
7400d781 | 201 | if (av->dccpav_vec_len + packets > DCCP_MAX_ACKVEC_LEN) |
ae31c339 ACM |
202 | return -ENOBUFS; |
203 | ||
204 | gap = packets - 1; | |
205 | new_head = av->dccpav_buf_head - packets; | |
206 | ||
207 | if (new_head < 0) { | |
208 | if (gap > 0) { | |
209 | memset(av->dccpav_buf, DCCP_ACKVEC_STATE_NOT_RECEIVED, | |
210 | gap + new_head + 1); | |
211 | gap = -new_head; | |
212 | } | |
7400d781 | 213 | new_head += DCCP_MAX_ACKVEC_LEN; |
ae31c339 ACM |
214 | } |
215 | ||
216 | av->dccpav_buf_head = new_head; | |
217 | ||
218 | if (gap > 0) | |
219 | memset(av->dccpav_buf + av->dccpav_buf_head + 1, | |
220 | DCCP_ACKVEC_STATE_NOT_RECEIVED, gap); | |
221 | ||
222 | av->dccpav_buf[av->dccpav_buf_head] = state; | |
223 | av->dccpav_vec_len += packets; | |
224 | return 0; | |
225 | } | |
226 | ||
227 | /* | |
228 | * Implements the draft-ietf-dccp-spec-11.txt Appendix A | |
229 | */ | |
230 | int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk, | |
231 | const u64 ackno, const u8 state) | |
232 | { | |
233 | /* | |
234 | * Check at the right places if the buffer is full, if it is, tell the | |
235 | * caller to start dropping packets till the HC-Sender acks our ACK | |
236 | * vectors, when we will free up space in dccpav_buf. | |
237 | * | |
238 | * We may well decide to do buffer compression, etc, but for now lets | |
239 | * just drop. | |
240 | * | |
241 | * From Appendix A: | |
242 | * | |
243 | * Of course, the circular buffer may overflow, either when the | |
244 | * HC-Sender is sending data at a very high rate, when the | |
245 | * HC-Receiver's acknowledgements are not reaching the HC-Sender, | |
246 | * or when the HC-Sender is forgetting to acknowledge those acks | |
247 | * (so the HC-Receiver is unable to clean up old state). In this | |
248 | * case, the HC-Receiver should either compress the buffer (by | |
249 | * increasing run lengths when possible), transfer its state to | |
250 | * a larger buffer, or, as a last resort, drop all received | |
251 | * packets, without processing them whatsoever, until its buffer | |
252 | * shrinks again. | |
253 | */ | |
254 | ||
255 | /* See if this is the first ackno being inserted */ | |
256 | if (av->dccpav_vec_len == 0) { | |
257 | av->dccpav_buf[av->dccpav_buf_head] = state; | |
258 | av->dccpav_vec_len = 1; | |
259 | } else if (after48(ackno, av->dccpav_buf_ackno)) { | |
260 | const u64 delta = dccp_delta_seqno(av->dccpav_buf_ackno, | |
261 | ackno); | |
262 | ||
263 | /* | |
264 | * Look if the state of this packet is the same as the | |
265 | * previous ackno and if so if we can bump the head len. | |
266 | */ | |
267 | if (delta == 1 && | |
268 | dccp_ackvec_state(av, av->dccpav_buf_head) == state && | |
269 | (dccp_ackvec_len(av, av->dccpav_buf_head) < | |
270 | DCCP_ACKVEC_LEN_MASK)) | |
271 | av->dccpav_buf[av->dccpav_buf_head]++; | |
272 | else if (dccp_ackvec_set_buf_head_state(av, delta, state)) | |
273 | return -ENOBUFS; | |
274 | } else { | |
275 | /* | |
276 | * A.1.2. Old Packets | |
277 | * | |
278 | * When a packet with Sequence Number S arrives, and | |
279 | * S <= buf_ackno, the HC-Receiver will scan the table | |
280 | * for the byte corresponding to S. (Indexing structures | |
281 | * could reduce the complexity of this scan.) | |
282 | */ | |
283 | u64 delta = dccp_delta_seqno(ackno, av->dccpav_buf_ackno); | |
e4dfd449 | 284 | u8 index = av->dccpav_buf_head; |
ae31c339 ACM |
285 | |
286 | while (1) { | |
287 | const u8 len = dccp_ackvec_len(av, index); | |
288 | const u8 state = dccp_ackvec_state(av, index); | |
289 | /* | |
290 | * valid packets not yet in dccpav_buf have a reserved | |
291 | * entry, with a len equal to 0. | |
292 | */ | |
293 | if (state == DCCP_ACKVEC_STATE_NOT_RECEIVED && | |
294 | len == 0 && delta == 0) { /* Found our | |
295 | reserved seat! */ | |
296 | dccp_pr_debug("Found %llu reserved seat!\n", | |
297 | (unsigned long long)ackno); | |
298 | av->dccpav_buf[index] = state; | |
299 | goto out; | |
300 | } | |
301 | /* len == 0 means one packet */ | |
302 | if (delta < len + 1) | |
303 | goto out_duplicate; | |
304 | ||
305 | delta -= len + 1; | |
7400d781 | 306 | if (++index == DCCP_MAX_ACKVEC_LEN) |
ae31c339 ACM |
307 | index = 0; |
308 | } | |
309 | } | |
310 | ||
311 | av->dccpav_buf_ackno = ackno; | |
312 | dccp_timestamp(sk, &av->dccpav_time); | |
313 | out: | |
ae31c339 ACM |
314 | return 0; |
315 | ||
316 | out_duplicate: | |
317 | /* Duplicate packet */ | |
318 | dccp_pr_debug("Received a dup or already considered lost " | |
319 | "packet: %llu\n", (unsigned long long)ackno); | |
320 | return -EILSEQ; | |
321 | } | |
322 | ||
323 | #ifdef CONFIG_IP_DCCP_DEBUG | |
324 | void dccp_ackvector_print(const u64 ackno, const unsigned char *vector, int len) | |
325 | { | |
326 | if (!dccp_debug) | |
327 | return; | |
328 | ||
329 | printk("ACK vector len=%d, ackno=%llu |", len, | |
330 | (unsigned long long)ackno); | |
331 | ||
332 | while (len--) { | |
333 | const u8 state = (*vector & DCCP_ACKVEC_STATE_MASK) >> 6; | |
334 | const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK; | |
335 | ||
336 | printk("%d,%d|", state, rl); | |
337 | ++vector; | |
338 | } | |
339 | ||
340 | printk("\n"); | |
341 | } | |
342 | ||
343 | void dccp_ackvec_print(const struct dccp_ackvec *av) | |
344 | { | |
345 | dccp_ackvector_print(av->dccpav_buf_ackno, | |
346 | av->dccpav_buf + av->dccpav_buf_head, | |
347 | av->dccpav_vec_len); | |
348 | } | |
349 | #endif | |
350 | ||
02bcf28c AB |
351 | static void dccp_ackvec_throw_record(struct dccp_ackvec *av, |
352 | struct dccp_ackvec_record *avr) | |
ae31c339 | 353 | { |
02bcf28c AB |
354 | struct dccp_ackvec_record *next; |
355 | ||
356 | av->dccpav_buf_tail = avr->dccpavr_ack_ptr - 1; | |
357 | if (av->dccpav_buf_tail == 0) | |
358 | av->dccpav_buf_tail = DCCP_MAX_ACKVEC_LEN - 1; | |
359 | ||
360 | av->dccpav_vec_len -= avr->dccpavr_sent_len; | |
361 | ||
362 | /* free records */ | |
363 | list_for_each_entry_safe_from(avr, next, &av->dccpav_records, | |
364 | dccpavr_node) { | |
365 | list_del_init(&avr->dccpavr_node); | |
366 | dccp_ackvec_record_delete(avr); | |
367 | } | |
ae31c339 ACM |
368 | } |
369 | ||
370 | void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, struct sock *sk, | |
371 | const u64 ackno) | |
372 | { | |
02bcf28c | 373 | struct dccp_ackvec_record *avr; |
ae31c339 | 374 | |
02bcf28c AB |
375 | /* |
376 | * If we traverse backwards, it should be faster when we have large | |
377 | * windows. We will be receiving ACKs for stuff we sent a while back | |
378 | * -sorbo. | |
379 | */ | |
380 | list_for_each_entry_reverse(avr, &av->dccpav_records, dccpavr_node) { | |
381 | if (ackno == avr->dccpavr_ack_seqno) { | |
ae31c339 | 382 | #ifdef CONFIG_IP_DCCP_DEBUG |
02bcf28c AB |
383 | struct dccp_sock *dp = dccp_sk(sk); |
384 | const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ? | |
385 | "CLIENT rx ack: " : "server rx ack: "; | |
ae31c339 | 386 | #endif |
02bcf28c AB |
387 | dccp_pr_debug("%sACK packet 0, len=%d, ack_seqno=%llu, " |
388 | "ack_ackno=%llu, ACKED!\n", | |
389 | debug_prefix, 1, | |
390 | (unsigned long long)avr->dccpavr_ack_seqno, | |
391 | (unsigned long long)avr->dccpavr_ack_ackno); | |
392 | dccp_ackvec_throw_record(av, avr); | |
393 | break; | |
394 | } | |
ae31c339 ACM |
395 | } |
396 | } | |
397 | ||
398 | static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av, | |
399 | struct sock *sk, u64 ackno, | |
400 | const unsigned char len, | |
401 | const unsigned char *vector) | |
402 | { | |
403 | unsigned char i; | |
02bcf28c | 404 | struct dccp_ackvec_record *avr; |
ae31c339 ACM |
405 | |
406 | /* Check if we actually sent an ACK vector */ | |
02bcf28c | 407 | if (list_empty(&av->dccpav_records)) |
ae31c339 | 408 | return; |
ae31c339 ACM |
409 | |
410 | i = len; | |
02bcf28c AB |
411 | /* |
412 | * XXX | |
413 | * I think it might be more efficient to work backwards. See comment on | |
414 | * rcv_ackno. -sorbo. | |
415 | */ | |
416 | avr = list_entry(av->dccpav_records.next, struct dccp_ackvec_record, | |
417 | dccpavr_node); | |
ae31c339 ACM |
418 | while (i--) { |
419 | const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK; | |
420 | u64 ackno_end_rl; | |
421 | ||
422 | dccp_set_seqno(&ackno_end_rl, ackno - rl); | |
423 | ||
424 | /* | |
02bcf28c AB |
425 | * If our AVR sequence number is greater than the ack, go |
426 | * forward in the AVR list until it is not so. | |
ae31c339 | 427 | */ |
02bcf28c AB |
428 | list_for_each_entry_from(avr, &av->dccpav_records, |
429 | dccpavr_node) { | |
430 | if (!after48(avr->dccpavr_ack_seqno, ackno)) | |
431 | goto found; | |
432 | } | |
433 | /* End of the dccpav_records list, not found, exit */ | |
434 | break; | |
435 | found: | |
436 | if (between48(avr->dccpavr_ack_seqno, ackno_end_rl, ackno)) { | |
ae31c339 ACM |
437 | const u8 state = (*vector & |
438 | DCCP_ACKVEC_STATE_MASK) >> 6; | |
ae31c339 ACM |
439 | if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) { |
440 | #ifdef CONFIG_IP_DCCP_DEBUG | |
441 | struct dccp_sock *dp = dccp_sk(sk); | |
442 | const char *debug_prefix = | |
443 | dp->dccps_role == DCCP_ROLE_CLIENT ? | |
444 | "CLIENT rx ack: " : "server rx ack: "; | |
445 | #endif | |
446 | dccp_pr_debug("%sACK vector 0, len=%d, " | |
447 | "ack_seqno=%llu, ack_ackno=%llu, " | |
448 | "ACKED!\n", | |
449 | debug_prefix, len, | |
450 | (unsigned long long) | |
02bcf28c | 451 | avr->dccpavr_ack_seqno, |
ae31c339 | 452 | (unsigned long long) |
02bcf28c AB |
453 | avr->dccpavr_ack_ackno); |
454 | dccp_ackvec_throw_record(av, avr); | |
afec35e3 | 455 | break; |
ae31c339 ACM |
456 | } |
457 | /* | |
02bcf28c AB |
458 | * If it wasn't received, continue scanning... we might |
459 | * find another one. | |
ae31c339 | 460 | */ |
ae31c339 | 461 | } |
ae31c339 ACM |
462 | |
463 | dccp_set_seqno(&ackno, ackno_end_rl - 1); | |
464 | ++vector; | |
465 | } | |
466 | } | |
467 | ||
468 | int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb, | |
469 | const u8 opt, const u8 *value, const u8 len) | |
470 | { | |
471 | if (len > DCCP_MAX_ACKVEC_LEN) | |
472 | return -1; | |
473 | ||
474 | /* dccp_ackvector_print(DCCP_SKB_CB(skb)->dccpd_ack_seq, value, len); */ | |
475 | dccp_ackvec_check_rcv_ackvector(dccp_sk(sk)->dccps_hc_rx_ackvec, sk, | |
476 | DCCP_SKB_CB(skb)->dccpd_ack_seq, | |
477 | len, value); | |
478 | return 0; | |
479 | } | |
9b07ef5d ACM |
480 | |
481 | static char dccp_ackvec_slab_msg[] __initdata = | |
02bcf28c | 482 | KERN_CRIT "DCCP: Unable to create ack vectors slab caches\n"; |
9b07ef5d ACM |
483 | |
484 | int __init dccp_ackvec_init(void) | |
485 | { | |
486 | dccp_ackvec_slab = kmem_cache_create("dccp_ackvec", | |
487 | sizeof(struct dccp_ackvec), 0, | |
488 | SLAB_HWCACHE_ALIGN, NULL, NULL); | |
02bcf28c AB |
489 | if (dccp_ackvec_slab == NULL) |
490 | goto out_err; | |
491 | ||
492 | dccp_ackvec_record_slab = | |
493 | kmem_cache_create("dccp_ackvec_record", | |
494 | sizeof(struct dccp_ackvec_record), | |
495 | 0, SLAB_HWCACHE_ALIGN, NULL, NULL); | |
496 | if (dccp_ackvec_record_slab == NULL) | |
497 | goto out_destroy_slab; | |
9b07ef5d ACM |
498 | |
499 | return 0; | |
02bcf28c AB |
500 | |
501 | out_destroy_slab: | |
502 | kmem_cache_destroy(dccp_ackvec_slab); | |
503 | dccp_ackvec_slab = NULL; | |
504 | out_err: | |
505 | printk(dccp_ackvec_slab_msg); | |
506 | return -ENOBUFS; | |
9b07ef5d ACM |
507 | } |
508 | ||
509 | void dccp_ackvec_exit(void) | |
510 | { | |
511 | if (dccp_ackvec_slab != NULL) { | |
512 | kmem_cache_destroy(dccp_ackvec_slab); | |
513 | dccp_ackvec_slab = NULL; | |
514 | } | |
02bcf28c AB |
515 | if (dccp_ackvec_record_slab != NULL) { |
516 | kmem_cache_destroy(dccp_ackvec_record_slab); | |
517 | dccp_ackvec_record_slab = NULL; | |
518 | } | |
9b07ef5d | 519 | } |