Commit | Line | Data |
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51c5d0c4 DM |
1 | #include <linux/rcupdate.h> |
2 | #include <linux/spinlock.h> | |
3 | #include <linux/jiffies.h> | |
ab92bb2f | 4 | #include <linux/module.h> |
4aabd8ef | 5 | #include <linux/cache.h> |
51c5d0c4 DM |
6 | #include <linux/slab.h> |
7 | #include <linux/init.h> | |
4aabd8ef | 8 | #include <linux/tcp.h> |
5815d5e7 | 9 | #include <linux/hash.h> |
d23ff701 | 10 | #include <linux/tcp_metrics.h> |
976a702a | 11 | #include <linux/vmalloc.h> |
4aabd8ef DM |
12 | |
13 | #include <net/inet_connection_sock.h> | |
51c5d0c4 | 14 | #include <net/net_namespace.h> |
ab92bb2f | 15 | #include <net/request_sock.h> |
51c5d0c4 | 16 | #include <net/inetpeer.h> |
4aabd8ef | 17 | #include <net/sock.h> |
51c5d0c4 | 18 | #include <net/ipv6.h> |
4aabd8ef DM |
19 | #include <net/dst.h> |
20 | #include <net/tcp.h> | |
d23ff701 | 21 | #include <net/genetlink.h> |
4aabd8ef DM |
22 | |
23 | int sysctl_tcp_nometrics_save __read_mostly; | |
24 | ||
1fe4c481 YC |
25 | struct tcp_fastopen_metrics { |
26 | u16 mss; | |
aab48743 YC |
27 | u16 syn_loss:10; /* Recurring Fast Open SYN losses */ |
28 | unsigned long last_syn_loss; /* Last Fast Open SYN loss */ | |
1fe4c481 YC |
29 | struct tcp_fastopen_cookie cookie; |
30 | }; | |
31 | ||
51c5d0c4 DM |
32 | struct tcp_metrics_block { |
33 | struct tcp_metrics_block __rcu *tcpm_next; | |
34 | struct inetpeer_addr tcpm_addr; | |
35 | unsigned long tcpm_stamp; | |
81166dd6 DM |
36 | u32 tcpm_ts; |
37 | u32 tcpm_ts_stamp; | |
51c5d0c4 | 38 | u32 tcpm_lock; |
d23ff701 | 39 | u32 tcpm_vals[TCP_METRIC_MAX + 1]; |
1fe4c481 | 40 | struct tcp_fastopen_metrics tcpm_fastopen; |
d23ff701 JA |
41 | |
42 | struct rcu_head rcu_head; | |
51c5d0c4 DM |
43 | }; |
44 | ||
45 | static bool tcp_metric_locked(struct tcp_metrics_block *tm, | |
46 | enum tcp_metric_index idx) | |
47 | { | |
48 | return tm->tcpm_lock & (1 << idx); | |
49 | } | |
50 | ||
51 | static u32 tcp_metric_get(struct tcp_metrics_block *tm, | |
52 | enum tcp_metric_index idx) | |
53 | { | |
54 | return tm->tcpm_vals[idx]; | |
55 | } | |
56 | ||
57 | static u32 tcp_metric_get_jiffies(struct tcp_metrics_block *tm, | |
58 | enum tcp_metric_index idx) | |
59 | { | |
60 | return msecs_to_jiffies(tm->tcpm_vals[idx]); | |
61 | } | |
62 | ||
63 | static void tcp_metric_set(struct tcp_metrics_block *tm, | |
64 | enum tcp_metric_index idx, | |
65 | u32 val) | |
66 | { | |
67 | tm->tcpm_vals[idx] = val; | |
68 | } | |
69 | ||
70 | static void tcp_metric_set_msecs(struct tcp_metrics_block *tm, | |
71 | enum tcp_metric_index idx, | |
72 | u32 val) | |
73 | { | |
74 | tm->tcpm_vals[idx] = jiffies_to_msecs(val); | |
75 | } | |
76 | ||
77 | static bool addr_same(const struct inetpeer_addr *a, | |
78 | const struct inetpeer_addr *b) | |
79 | { | |
80 | const struct in6_addr *a6, *b6; | |
81 | ||
82 | if (a->family != b->family) | |
83 | return false; | |
84 | if (a->family == AF_INET) | |
85 | return a->addr.a4 == b->addr.a4; | |
86 | ||
87 | a6 = (const struct in6_addr *) &a->addr.a6[0]; | |
88 | b6 = (const struct in6_addr *) &b->addr.a6[0]; | |
89 | ||
90 | return ipv6_addr_equal(a6, b6); | |
91 | } | |
92 | ||
93 | struct tcpm_hash_bucket { | |
94 | struct tcp_metrics_block __rcu *chain; | |
95 | }; | |
96 | ||
97 | static DEFINE_SPINLOCK(tcp_metrics_lock); | |
98 | ||
efeaa555 ED |
99 | static void tcpm_suck_dst(struct tcp_metrics_block *tm, struct dst_entry *dst, |
100 | bool fastopen_clear) | |
51c5d0c4 DM |
101 | { |
102 | u32 val; | |
103 | ||
9a0a9502 JA |
104 | tm->tcpm_stamp = jiffies; |
105 | ||
51c5d0c4 DM |
106 | val = 0; |
107 | if (dst_metric_locked(dst, RTAX_RTT)) | |
108 | val |= 1 << TCP_METRIC_RTT; | |
109 | if (dst_metric_locked(dst, RTAX_RTTVAR)) | |
110 | val |= 1 << TCP_METRIC_RTTVAR; | |
111 | if (dst_metric_locked(dst, RTAX_SSTHRESH)) | |
112 | val |= 1 << TCP_METRIC_SSTHRESH; | |
113 | if (dst_metric_locked(dst, RTAX_CWND)) | |
114 | val |= 1 << TCP_METRIC_CWND; | |
115 | if (dst_metric_locked(dst, RTAX_REORDERING)) | |
116 | val |= 1 << TCP_METRIC_REORDERING; | |
117 | tm->tcpm_lock = val; | |
118 | ||
119 | tm->tcpm_vals[TCP_METRIC_RTT] = dst_metric_raw(dst, RTAX_RTT); | |
120 | tm->tcpm_vals[TCP_METRIC_RTTVAR] = dst_metric_raw(dst, RTAX_RTTVAR); | |
121 | tm->tcpm_vals[TCP_METRIC_SSTHRESH] = dst_metric_raw(dst, RTAX_SSTHRESH); | |
122 | tm->tcpm_vals[TCP_METRIC_CWND] = dst_metric_raw(dst, RTAX_CWND); | |
123 | tm->tcpm_vals[TCP_METRIC_REORDERING] = dst_metric_raw(dst, RTAX_REORDERING); | |
81166dd6 DM |
124 | tm->tcpm_ts = 0; |
125 | tm->tcpm_ts_stamp = 0; | |
efeaa555 ED |
126 | if (fastopen_clear) { |
127 | tm->tcpm_fastopen.mss = 0; | |
128 | tm->tcpm_fastopen.syn_loss = 0; | |
129 | tm->tcpm_fastopen.cookie.len = 0; | |
130 | } | |
51c5d0c4 DM |
131 | } |
132 | ||
133 | static struct tcp_metrics_block *tcpm_new(struct dst_entry *dst, | |
134 | struct inetpeer_addr *addr, | |
135 | unsigned int hash, | |
136 | bool reclaim) | |
137 | { | |
138 | struct tcp_metrics_block *tm; | |
139 | struct net *net; | |
140 | ||
141 | spin_lock_bh(&tcp_metrics_lock); | |
142 | net = dev_net(dst->dev); | |
143 | if (unlikely(reclaim)) { | |
144 | struct tcp_metrics_block *oldest; | |
145 | ||
146 | oldest = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); | |
147 | for (tm = rcu_dereference(oldest->tcpm_next); tm; | |
148 | tm = rcu_dereference(tm->tcpm_next)) { | |
149 | if (time_before(tm->tcpm_stamp, oldest->tcpm_stamp)) | |
150 | oldest = tm; | |
151 | } | |
152 | tm = oldest; | |
153 | } else { | |
154 | tm = kmalloc(sizeof(*tm), GFP_ATOMIC); | |
155 | if (!tm) | |
156 | goto out_unlock; | |
157 | } | |
158 | tm->tcpm_addr = *addr; | |
51c5d0c4 | 159 | |
efeaa555 | 160 | tcpm_suck_dst(tm, dst, true); |
51c5d0c4 DM |
161 | |
162 | if (likely(!reclaim)) { | |
163 | tm->tcpm_next = net->ipv4.tcp_metrics_hash[hash].chain; | |
164 | rcu_assign_pointer(net->ipv4.tcp_metrics_hash[hash].chain, tm); | |
165 | } | |
166 | ||
167 | out_unlock: | |
168 | spin_unlock_bh(&tcp_metrics_lock); | |
169 | return tm; | |
170 | } | |
171 | ||
172 | #define TCP_METRICS_TIMEOUT (60 * 60 * HZ) | |
173 | ||
174 | static void tcpm_check_stamp(struct tcp_metrics_block *tm, struct dst_entry *dst) | |
175 | { | |
176 | if (tm && unlikely(time_after(jiffies, tm->tcpm_stamp + TCP_METRICS_TIMEOUT))) | |
efeaa555 | 177 | tcpm_suck_dst(tm, dst, false); |
51c5d0c4 DM |
178 | } |
179 | ||
180 | #define TCP_METRICS_RECLAIM_DEPTH 5 | |
181 | #define TCP_METRICS_RECLAIM_PTR (struct tcp_metrics_block *) 0x1UL | |
182 | ||
183 | static struct tcp_metrics_block *tcp_get_encode(struct tcp_metrics_block *tm, int depth) | |
184 | { | |
185 | if (tm) | |
186 | return tm; | |
187 | if (depth > TCP_METRICS_RECLAIM_DEPTH) | |
188 | return TCP_METRICS_RECLAIM_PTR; | |
189 | return NULL; | |
190 | } | |
191 | ||
192 | static struct tcp_metrics_block *__tcp_get_metrics(const struct inetpeer_addr *addr, | |
193 | struct net *net, unsigned int hash) | |
194 | { | |
195 | struct tcp_metrics_block *tm; | |
196 | int depth = 0; | |
197 | ||
198 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
199 | tm = rcu_dereference(tm->tcpm_next)) { | |
200 | if (addr_same(&tm->tcpm_addr, addr)) | |
201 | break; | |
202 | depth++; | |
203 | } | |
204 | return tcp_get_encode(tm, depth); | |
205 | } | |
206 | ||
207 | static struct tcp_metrics_block *__tcp_get_metrics_req(struct request_sock *req, | |
208 | struct dst_entry *dst) | |
209 | { | |
210 | struct tcp_metrics_block *tm; | |
211 | struct inetpeer_addr addr; | |
212 | unsigned int hash; | |
213 | struct net *net; | |
214 | ||
215 | addr.family = req->rsk_ops->family; | |
216 | switch (addr.family) { | |
217 | case AF_INET: | |
634fb979 | 218 | addr.addr.a4 = inet_rsk(req)->ir_rmt_addr; |
51c5d0c4 DM |
219 | hash = (__force unsigned int) addr.addr.a4; |
220 | break; | |
634fb979 | 221 | #if IS_ENABLED(CONFIG_IPV6) |
51c5d0c4 | 222 | case AF_INET6: |
634fb979 ED |
223 | *(struct in6_addr *)addr.addr.a6 = inet_rsk(req)->ir_v6_rmt_addr; |
224 | hash = ipv6_addr_hash(&inet_rsk(req)->ir_v6_rmt_addr); | |
51c5d0c4 | 225 | break; |
634fb979 | 226 | #endif |
51c5d0c4 DM |
227 | default: |
228 | return NULL; | |
229 | } | |
230 | ||
51c5d0c4 | 231 | net = dev_net(dst->dev); |
5815d5e7 | 232 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
51c5d0c4 DM |
233 | |
234 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
235 | tm = rcu_dereference(tm->tcpm_next)) { | |
236 | if (addr_same(&tm->tcpm_addr, &addr)) | |
237 | break; | |
238 | } | |
239 | tcpm_check_stamp(tm, dst); | |
240 | return tm; | |
241 | } | |
242 | ||
81166dd6 DM |
243 | static struct tcp_metrics_block *__tcp_get_metrics_tw(struct inet_timewait_sock *tw) |
244 | { | |
81166dd6 DM |
245 | struct tcp_metrics_block *tm; |
246 | struct inetpeer_addr addr; | |
247 | unsigned int hash; | |
248 | struct net *net; | |
249 | ||
250 | addr.family = tw->tw_family; | |
251 | switch (addr.family) { | |
252 | case AF_INET: | |
253 | addr.addr.a4 = tw->tw_daddr; | |
254 | hash = (__force unsigned int) addr.addr.a4; | |
255 | break; | |
c2bb06db | 256 | #if IS_ENABLED(CONFIG_IPV6) |
81166dd6 | 257 | case AF_INET6: |
efe4208f ED |
258 | *(struct in6_addr *)addr.addr.a6 = tw->tw_v6_daddr; |
259 | hash = ipv6_addr_hash(&tw->tw_v6_daddr); | |
81166dd6 | 260 | break; |
c2bb06db | 261 | #endif |
81166dd6 DM |
262 | default: |
263 | return NULL; | |
264 | } | |
265 | ||
81166dd6 | 266 | net = twsk_net(tw); |
5815d5e7 | 267 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
81166dd6 DM |
268 | |
269 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
270 | tm = rcu_dereference(tm->tcpm_next)) { | |
271 | if (addr_same(&tm->tcpm_addr, &addr)) | |
272 | break; | |
273 | } | |
274 | return tm; | |
275 | } | |
276 | ||
51c5d0c4 DM |
277 | static struct tcp_metrics_block *tcp_get_metrics(struct sock *sk, |
278 | struct dst_entry *dst, | |
279 | bool create) | |
280 | { | |
281 | struct tcp_metrics_block *tm; | |
282 | struct inetpeer_addr addr; | |
283 | unsigned int hash; | |
284 | struct net *net; | |
285 | bool reclaim; | |
286 | ||
287 | addr.family = sk->sk_family; | |
288 | switch (addr.family) { | |
289 | case AF_INET: | |
290 | addr.addr.a4 = inet_sk(sk)->inet_daddr; | |
291 | hash = (__force unsigned int) addr.addr.a4; | |
292 | break; | |
c2bb06db | 293 | #if IS_ENABLED(CONFIG_IPV6) |
51c5d0c4 | 294 | case AF_INET6: |
efe4208f ED |
295 | *(struct in6_addr *)addr.addr.a6 = sk->sk_v6_daddr; |
296 | hash = ipv6_addr_hash(&sk->sk_v6_daddr); | |
51c5d0c4 | 297 | break; |
c2bb06db | 298 | #endif |
51c5d0c4 DM |
299 | default: |
300 | return NULL; | |
301 | } | |
302 | ||
51c5d0c4 | 303 | net = dev_net(dst->dev); |
5815d5e7 | 304 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
51c5d0c4 DM |
305 | |
306 | tm = __tcp_get_metrics(&addr, net, hash); | |
307 | reclaim = false; | |
308 | if (tm == TCP_METRICS_RECLAIM_PTR) { | |
309 | reclaim = true; | |
310 | tm = NULL; | |
311 | } | |
312 | if (!tm && create) | |
313 | tm = tcpm_new(dst, &addr, hash, reclaim); | |
314 | else | |
315 | tcpm_check_stamp(tm, dst); | |
316 | ||
317 | return tm; | |
318 | } | |
319 | ||
4aabd8ef DM |
320 | /* Save metrics learned by this TCP session. This function is called |
321 | * only, when TCP finishes successfully i.e. when it enters TIME-WAIT | |
322 | * or goes from LAST-ACK to CLOSE. | |
323 | */ | |
324 | void tcp_update_metrics(struct sock *sk) | |
325 | { | |
51c5d0c4 | 326 | const struct inet_connection_sock *icsk = inet_csk(sk); |
4aabd8ef | 327 | struct dst_entry *dst = __sk_dst_get(sk); |
51c5d0c4 DM |
328 | struct tcp_sock *tp = tcp_sk(sk); |
329 | struct tcp_metrics_block *tm; | |
330 | unsigned long rtt; | |
331 | u32 val; | |
332 | int m; | |
4aabd8ef | 333 | |
51c5d0c4 | 334 | if (sysctl_tcp_nometrics_save || !dst) |
4aabd8ef DM |
335 | return; |
336 | ||
51c5d0c4 | 337 | if (dst->flags & DST_HOST) |
4aabd8ef DM |
338 | dst_confirm(dst); |
339 | ||
51c5d0c4 DM |
340 | rcu_read_lock(); |
341 | if (icsk->icsk_backoff || !tp->srtt) { | |
342 | /* This session failed to estimate rtt. Why? | |
343 | * Probably, no packets returned in time. Reset our | |
344 | * results. | |
345 | */ | |
346 | tm = tcp_get_metrics(sk, dst, false); | |
347 | if (tm && !tcp_metric_locked(tm, TCP_METRIC_RTT)) | |
348 | tcp_metric_set(tm, TCP_METRIC_RTT, 0); | |
349 | goto out_unlock; | |
350 | } else | |
351 | tm = tcp_get_metrics(sk, dst, true); | |
4aabd8ef | 352 | |
51c5d0c4 DM |
353 | if (!tm) |
354 | goto out_unlock; | |
4aabd8ef | 355 | |
51c5d0c4 DM |
356 | rtt = tcp_metric_get_jiffies(tm, TCP_METRIC_RTT); |
357 | m = rtt - tp->srtt; | |
4aabd8ef | 358 | |
51c5d0c4 DM |
359 | /* If newly calculated rtt larger than stored one, store new |
360 | * one. Otherwise, use EWMA. Remember, rtt overestimation is | |
361 | * always better than underestimation. | |
362 | */ | |
363 | if (!tcp_metric_locked(tm, TCP_METRIC_RTT)) { | |
364 | if (m <= 0) | |
365 | rtt = tp->srtt; | |
366 | else | |
367 | rtt -= (m >> 3); | |
368 | tcp_metric_set_msecs(tm, TCP_METRIC_RTT, rtt); | |
369 | } | |
4aabd8ef | 370 | |
51c5d0c4 DM |
371 | if (!tcp_metric_locked(tm, TCP_METRIC_RTTVAR)) { |
372 | unsigned long var; | |
4aabd8ef | 373 | |
51c5d0c4 DM |
374 | if (m < 0) |
375 | m = -m; | |
4aabd8ef | 376 | |
51c5d0c4 DM |
377 | /* Scale deviation to rttvar fixed point */ |
378 | m >>= 1; | |
379 | if (m < tp->mdev) | |
380 | m = tp->mdev; | |
4aabd8ef | 381 | |
51c5d0c4 DM |
382 | var = tcp_metric_get_jiffies(tm, TCP_METRIC_RTTVAR); |
383 | if (m >= var) | |
384 | var = m; | |
385 | else | |
386 | var -= (var - m) >> 2; | |
4aabd8ef | 387 | |
51c5d0c4 DM |
388 | tcp_metric_set_msecs(tm, TCP_METRIC_RTTVAR, var); |
389 | } | |
390 | ||
391 | if (tcp_in_initial_slowstart(tp)) { | |
392 | /* Slow start still did not finish. */ | |
393 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) { | |
394 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
395 | if (val && (tp->snd_cwnd >> 1) > val) | |
396 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, | |
397 | tp->snd_cwnd >> 1); | |
398 | } | |
399 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { | |
400 | val = tcp_metric_get(tm, TCP_METRIC_CWND); | |
401 | if (tp->snd_cwnd > val) | |
402 | tcp_metric_set(tm, TCP_METRIC_CWND, | |
403 | tp->snd_cwnd); | |
404 | } | |
405 | } else if (tp->snd_cwnd > tp->snd_ssthresh && | |
406 | icsk->icsk_ca_state == TCP_CA_Open) { | |
407 | /* Cong. avoidance phase, cwnd is reliable. */ | |
408 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) | |
409 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, | |
410 | max(tp->snd_cwnd >> 1, tp->snd_ssthresh)); | |
411 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { | |
412 | val = tcp_metric_get(tm, TCP_METRIC_CWND); | |
2100844c | 413 | tcp_metric_set(tm, TCP_METRIC_CWND, (val + tp->snd_cwnd) >> 1); |
51c5d0c4 DM |
414 | } |
415 | } else { | |
416 | /* Else slow start did not finish, cwnd is non-sense, | |
417 | * ssthresh may be also invalid. | |
418 | */ | |
419 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { | |
420 | val = tcp_metric_get(tm, TCP_METRIC_CWND); | |
421 | tcp_metric_set(tm, TCP_METRIC_CWND, | |
422 | (val + tp->snd_ssthresh) >> 1); | |
423 | } | |
424 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) { | |
425 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
426 | if (val && tp->snd_ssthresh > val) | |
427 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, | |
428 | tp->snd_ssthresh); | |
429 | } | |
430 | if (!tcp_metric_locked(tm, TCP_METRIC_REORDERING)) { | |
431 | val = tcp_metric_get(tm, TCP_METRIC_REORDERING); | |
432 | if (val < tp->reordering && | |
4aabd8ef | 433 | tp->reordering != sysctl_tcp_reordering) |
51c5d0c4 DM |
434 | tcp_metric_set(tm, TCP_METRIC_REORDERING, |
435 | tp->reordering); | |
4aabd8ef DM |
436 | } |
437 | } | |
51c5d0c4 DM |
438 | tm->tcpm_stamp = jiffies; |
439 | out_unlock: | |
440 | rcu_read_unlock(); | |
4aabd8ef DM |
441 | } |
442 | ||
443 | /* Initialize metrics on socket. */ | |
444 | ||
445 | void tcp_init_metrics(struct sock *sk) | |
446 | { | |
4aabd8ef | 447 | struct dst_entry *dst = __sk_dst_get(sk); |
51c5d0c4 DM |
448 | struct tcp_sock *tp = tcp_sk(sk); |
449 | struct tcp_metrics_block *tm; | |
1b7fdd2a | 450 | u32 val, crtt = 0; /* cached RTT scaled by 8 */ |
4aabd8ef DM |
451 | |
452 | if (dst == NULL) | |
453 | goto reset; | |
454 | ||
455 | dst_confirm(dst); | |
456 | ||
51c5d0c4 DM |
457 | rcu_read_lock(); |
458 | tm = tcp_get_metrics(sk, dst, true); | |
459 | if (!tm) { | |
460 | rcu_read_unlock(); | |
461 | goto reset; | |
462 | } | |
463 | ||
464 | if (tcp_metric_locked(tm, TCP_METRIC_CWND)) | |
465 | tp->snd_cwnd_clamp = tcp_metric_get(tm, TCP_METRIC_CWND); | |
466 | ||
467 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
468 | if (val) { | |
469 | tp->snd_ssthresh = val; | |
4aabd8ef DM |
470 | if (tp->snd_ssthresh > tp->snd_cwnd_clamp) |
471 | tp->snd_ssthresh = tp->snd_cwnd_clamp; | |
472 | } else { | |
473 | /* ssthresh may have been reduced unnecessarily during. | |
474 | * 3WHS. Restore it back to its initial default. | |
475 | */ | |
476 | tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; | |
477 | } | |
51c5d0c4 DM |
478 | val = tcp_metric_get(tm, TCP_METRIC_REORDERING); |
479 | if (val && tp->reordering != val) { | |
4aabd8ef DM |
480 | tcp_disable_fack(tp); |
481 | tcp_disable_early_retrans(tp); | |
51c5d0c4 | 482 | tp->reordering = val; |
4aabd8ef DM |
483 | } |
484 | ||
1b7fdd2a | 485 | crtt = tcp_metric_get_jiffies(tm, TCP_METRIC_RTT); |
51c5d0c4 | 486 | rcu_read_unlock(); |
4aabd8ef | 487 | reset: |
52f20e65 YC |
488 | /* The initial RTT measurement from the SYN/SYN-ACK is not ideal |
489 | * to seed the RTO for later data packets because SYN packets are | |
490 | * small. Use the per-dst cached values to seed the RTO but keep | |
491 | * the RTT estimator variables intact (e.g., srtt, mdev, rttvar). | |
492 | * Later the RTO will be updated immediately upon obtaining the first | |
493 | * data RTT sample (tcp_rtt_estimator()). Hence the cached RTT only | |
494 | * influences the first RTO but not later RTT estimation. | |
495 | * | |
496 | * But if RTT is not available from the SYN (due to retransmits or | |
497 | * syn cookies) or the cache, force a conservative 3secs timeout. | |
498 | * | |
499 | * A bit of theory. RTT is time passed after "normal" sized packet | |
500 | * is sent until it is ACKed. In normal circumstances sending small | |
501 | * packets force peer to delay ACKs and calculation is correct too. | |
502 | * The algorithm is adaptive and, provided we follow specs, it | |
503 | * NEVER underestimate RTT. BUT! If peer tries to make some clever | |
504 | * tricks sort of "quick acks" for time long enough to decrease RTT | |
505 | * to low value, and then abruptly stops to do it and starts to delay | |
506 | * ACKs, wait for troubles. | |
507 | */ | |
1b7fdd2a | 508 | if (crtt > tp->srtt) { |
269aa759 NC |
509 | /* Set RTO like tcp_rtt_estimator(), but from cached RTT. */ |
510 | crtt >>= 3; | |
511 | inet_csk(sk)->icsk_rto = crtt + max(2 * crtt, tcp_rto_min(sk)); | |
1b7fdd2a | 512 | } else if (tp->srtt == 0) { |
4aabd8ef DM |
513 | /* RFC6298: 5.7 We've failed to get a valid RTT sample from |
514 | * 3WHS. This is most likely due to retransmission, | |
515 | * including spurious one. Reset the RTO back to 3secs | |
516 | * from the more aggressive 1sec to avoid more spurious | |
517 | * retransmission. | |
518 | */ | |
519 | tp->mdev = tp->mdev_max = tp->rttvar = TCP_TIMEOUT_FALLBACK; | |
520 | inet_csk(sk)->icsk_rto = TCP_TIMEOUT_FALLBACK; | |
521 | } | |
522 | /* Cut cwnd down to 1 per RFC5681 if SYN or SYN-ACK has been | |
523 | * retransmitted. In light of RFC6298 more aggressive 1sec | |
524 | * initRTO, we only reset cwnd when more than 1 SYN/SYN-ACK | |
525 | * retransmission has occurred. | |
526 | */ | |
527 | if (tp->total_retrans > 1) | |
528 | tp->snd_cwnd = 1; | |
529 | else | |
530 | tp->snd_cwnd = tcp_init_cwnd(tp, dst); | |
531 | tp->snd_cwnd_stamp = tcp_time_stamp; | |
532 | } | |
ab92bb2f | 533 | |
81166dd6 | 534 | bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst, bool paws_check) |
ab92bb2f | 535 | { |
51c5d0c4 DM |
536 | struct tcp_metrics_block *tm; |
537 | bool ret; | |
538 | ||
ab92bb2f DM |
539 | if (!dst) |
540 | return false; | |
51c5d0c4 DM |
541 | |
542 | rcu_read_lock(); | |
543 | tm = __tcp_get_metrics_req(req, dst); | |
81166dd6 DM |
544 | if (paws_check) { |
545 | if (tm && | |
546 | (u32)get_seconds() - tm->tcpm_ts_stamp < TCP_PAWS_MSL && | |
547 | (s32)(tm->tcpm_ts - req->ts_recent) > TCP_PAWS_WINDOW) | |
548 | ret = false; | |
549 | else | |
550 | ret = true; | |
551 | } else { | |
552 | if (tm && tcp_metric_get(tm, TCP_METRIC_RTT) && tm->tcpm_ts_stamp) | |
553 | ret = true; | |
554 | else | |
555 | ret = false; | |
556 | } | |
51c5d0c4 DM |
557 | rcu_read_unlock(); |
558 | ||
559 | return ret; | |
ab92bb2f DM |
560 | } |
561 | EXPORT_SYMBOL_GPL(tcp_peer_is_proven); | |
51c5d0c4 | 562 | |
81166dd6 DM |
563 | void tcp_fetch_timewait_stamp(struct sock *sk, struct dst_entry *dst) |
564 | { | |
565 | struct tcp_metrics_block *tm; | |
566 | ||
567 | rcu_read_lock(); | |
568 | tm = tcp_get_metrics(sk, dst, true); | |
569 | if (tm) { | |
570 | struct tcp_sock *tp = tcp_sk(sk); | |
571 | ||
572 | if ((u32)get_seconds() - tm->tcpm_ts_stamp <= TCP_PAWS_MSL) { | |
573 | tp->rx_opt.ts_recent_stamp = tm->tcpm_ts_stamp; | |
574 | tp->rx_opt.ts_recent = tm->tcpm_ts; | |
575 | } | |
576 | } | |
577 | rcu_read_unlock(); | |
578 | } | |
579 | EXPORT_SYMBOL_GPL(tcp_fetch_timewait_stamp); | |
580 | ||
581 | /* VJ's idea. Save last timestamp seen from this destination and hold | |
582 | * it at least for normal timewait interval to use for duplicate | |
583 | * segment detection in subsequent connections, before they enter | |
584 | * synchronized state. | |
585 | */ | |
586 | bool tcp_remember_stamp(struct sock *sk) | |
587 | { | |
588 | struct dst_entry *dst = __sk_dst_get(sk); | |
589 | bool ret = false; | |
590 | ||
591 | if (dst) { | |
592 | struct tcp_metrics_block *tm; | |
593 | ||
594 | rcu_read_lock(); | |
595 | tm = tcp_get_metrics(sk, dst, true); | |
596 | if (tm) { | |
597 | struct tcp_sock *tp = tcp_sk(sk); | |
598 | ||
599 | if ((s32)(tm->tcpm_ts - tp->rx_opt.ts_recent) <= 0 || | |
600 | ((u32)get_seconds() - tm->tcpm_ts_stamp > TCP_PAWS_MSL && | |
601 | tm->tcpm_ts_stamp <= (u32)tp->rx_opt.ts_recent_stamp)) { | |
602 | tm->tcpm_ts_stamp = (u32)tp->rx_opt.ts_recent_stamp; | |
603 | tm->tcpm_ts = tp->rx_opt.ts_recent; | |
604 | } | |
605 | ret = true; | |
606 | } | |
607 | rcu_read_unlock(); | |
608 | } | |
609 | return ret; | |
610 | } | |
611 | ||
612 | bool tcp_tw_remember_stamp(struct inet_timewait_sock *tw) | |
613 | { | |
614 | struct tcp_metrics_block *tm; | |
615 | bool ret = false; | |
616 | ||
617 | rcu_read_lock(); | |
618 | tm = __tcp_get_metrics_tw(tw); | |
9a0a9502 | 619 | if (tm) { |
81166dd6 DM |
620 | const struct tcp_timewait_sock *tcptw; |
621 | struct sock *sk = (struct sock *) tw; | |
622 | ||
623 | tcptw = tcp_twsk(sk); | |
624 | if ((s32)(tm->tcpm_ts - tcptw->tw_ts_recent) <= 0 || | |
625 | ((u32)get_seconds() - tm->tcpm_ts_stamp > TCP_PAWS_MSL && | |
626 | tm->tcpm_ts_stamp <= (u32)tcptw->tw_ts_recent_stamp)) { | |
627 | tm->tcpm_ts_stamp = (u32)tcptw->tw_ts_recent_stamp; | |
628 | tm->tcpm_ts = tcptw->tw_ts_recent; | |
629 | } | |
630 | ret = true; | |
631 | } | |
632 | rcu_read_unlock(); | |
633 | ||
634 | return ret; | |
635 | } | |
636 | ||
1fe4c481 YC |
637 | static DEFINE_SEQLOCK(fastopen_seqlock); |
638 | ||
639 | void tcp_fastopen_cache_get(struct sock *sk, u16 *mss, | |
aab48743 YC |
640 | struct tcp_fastopen_cookie *cookie, |
641 | int *syn_loss, unsigned long *last_syn_loss) | |
1fe4c481 YC |
642 | { |
643 | struct tcp_metrics_block *tm; | |
644 | ||
645 | rcu_read_lock(); | |
646 | tm = tcp_get_metrics(sk, __sk_dst_get(sk), false); | |
647 | if (tm) { | |
648 | struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; | |
649 | unsigned int seq; | |
650 | ||
651 | do { | |
652 | seq = read_seqbegin(&fastopen_seqlock); | |
653 | if (tfom->mss) | |
654 | *mss = tfom->mss; | |
655 | *cookie = tfom->cookie; | |
aab48743 YC |
656 | *syn_loss = tfom->syn_loss; |
657 | *last_syn_loss = *syn_loss ? tfom->last_syn_loss : 0; | |
1fe4c481 YC |
658 | } while (read_seqretry(&fastopen_seqlock, seq)); |
659 | } | |
660 | rcu_read_unlock(); | |
661 | } | |
662 | ||
1fe4c481 | 663 | void tcp_fastopen_cache_set(struct sock *sk, u16 mss, |
aab48743 | 664 | struct tcp_fastopen_cookie *cookie, bool syn_lost) |
1fe4c481 | 665 | { |
dccf76ca | 666 | struct dst_entry *dst = __sk_dst_get(sk); |
1fe4c481 YC |
667 | struct tcp_metrics_block *tm; |
668 | ||
dccf76ca ED |
669 | if (!dst) |
670 | return; | |
1fe4c481 | 671 | rcu_read_lock(); |
dccf76ca | 672 | tm = tcp_get_metrics(sk, dst, true); |
1fe4c481 YC |
673 | if (tm) { |
674 | struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; | |
675 | ||
676 | write_seqlock_bh(&fastopen_seqlock); | |
c968601d YC |
677 | if (mss) |
678 | tfom->mss = mss; | |
679 | if (cookie && cookie->len > 0) | |
1fe4c481 | 680 | tfom->cookie = *cookie; |
aab48743 YC |
681 | if (syn_lost) { |
682 | ++tfom->syn_loss; | |
683 | tfom->last_syn_loss = jiffies; | |
684 | } else | |
685 | tfom->syn_loss = 0; | |
1fe4c481 YC |
686 | write_sequnlock_bh(&fastopen_seqlock); |
687 | } | |
688 | rcu_read_unlock(); | |
689 | } | |
690 | ||
d23ff701 JA |
691 | static struct genl_family tcp_metrics_nl_family = { |
692 | .id = GENL_ID_GENERATE, | |
693 | .hdrsize = 0, | |
694 | .name = TCP_METRICS_GENL_NAME, | |
695 | .version = TCP_METRICS_GENL_VERSION, | |
696 | .maxattr = TCP_METRICS_ATTR_MAX, | |
697 | .netnsok = true, | |
698 | }; | |
699 | ||
700 | static struct nla_policy tcp_metrics_nl_policy[TCP_METRICS_ATTR_MAX + 1] = { | |
701 | [TCP_METRICS_ATTR_ADDR_IPV4] = { .type = NLA_U32, }, | |
702 | [TCP_METRICS_ATTR_ADDR_IPV6] = { .type = NLA_BINARY, | |
703 | .len = sizeof(struct in6_addr), }, | |
704 | /* Following attributes are not received for GET/DEL, | |
705 | * we keep them for reference | |
706 | */ | |
707 | #if 0 | |
708 | [TCP_METRICS_ATTR_AGE] = { .type = NLA_MSECS, }, | |
709 | [TCP_METRICS_ATTR_TW_TSVAL] = { .type = NLA_U32, }, | |
710 | [TCP_METRICS_ATTR_TW_TS_STAMP] = { .type = NLA_S32, }, | |
711 | [TCP_METRICS_ATTR_VALS] = { .type = NLA_NESTED, }, | |
712 | [TCP_METRICS_ATTR_FOPEN_MSS] = { .type = NLA_U16, }, | |
713 | [TCP_METRICS_ATTR_FOPEN_SYN_DROPS] = { .type = NLA_U16, }, | |
714 | [TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS] = { .type = NLA_MSECS, }, | |
715 | [TCP_METRICS_ATTR_FOPEN_COOKIE] = { .type = NLA_BINARY, | |
716 | .len = TCP_FASTOPEN_COOKIE_MAX, }, | |
717 | #endif | |
718 | }; | |
719 | ||
720 | /* Add attributes, caller cancels its header on failure */ | |
721 | static int tcp_metrics_fill_info(struct sk_buff *msg, | |
722 | struct tcp_metrics_block *tm) | |
723 | { | |
724 | struct nlattr *nest; | |
725 | int i; | |
726 | ||
727 | switch (tm->tcpm_addr.family) { | |
728 | case AF_INET: | |
729 | if (nla_put_be32(msg, TCP_METRICS_ATTR_ADDR_IPV4, | |
730 | tm->tcpm_addr.addr.a4) < 0) | |
731 | goto nla_put_failure; | |
732 | break; | |
733 | case AF_INET6: | |
734 | if (nla_put(msg, TCP_METRICS_ATTR_ADDR_IPV6, 16, | |
735 | tm->tcpm_addr.addr.a6) < 0) | |
736 | goto nla_put_failure; | |
737 | break; | |
738 | default: | |
739 | return -EAFNOSUPPORT; | |
740 | } | |
741 | ||
742 | if (nla_put_msecs(msg, TCP_METRICS_ATTR_AGE, | |
743 | jiffies - tm->tcpm_stamp) < 0) | |
744 | goto nla_put_failure; | |
745 | if (tm->tcpm_ts_stamp) { | |
746 | if (nla_put_s32(msg, TCP_METRICS_ATTR_TW_TS_STAMP, | |
747 | (s32) (get_seconds() - tm->tcpm_ts_stamp)) < 0) | |
748 | goto nla_put_failure; | |
749 | if (nla_put_u32(msg, TCP_METRICS_ATTR_TW_TSVAL, | |
750 | tm->tcpm_ts) < 0) | |
751 | goto nla_put_failure; | |
752 | } | |
753 | ||
754 | { | |
755 | int n = 0; | |
756 | ||
757 | nest = nla_nest_start(msg, TCP_METRICS_ATTR_VALS); | |
758 | if (!nest) | |
759 | goto nla_put_failure; | |
760 | for (i = 0; i < TCP_METRIC_MAX + 1; i++) { | |
761 | if (!tm->tcpm_vals[i]) | |
762 | continue; | |
763 | if (nla_put_u32(msg, i + 1, tm->tcpm_vals[i]) < 0) | |
764 | goto nla_put_failure; | |
765 | n++; | |
766 | } | |
767 | if (n) | |
768 | nla_nest_end(msg, nest); | |
769 | else | |
770 | nla_nest_cancel(msg, nest); | |
771 | } | |
772 | ||
773 | { | |
774 | struct tcp_fastopen_metrics tfom_copy[1], *tfom; | |
775 | unsigned int seq; | |
776 | ||
777 | do { | |
778 | seq = read_seqbegin(&fastopen_seqlock); | |
779 | tfom_copy[0] = tm->tcpm_fastopen; | |
780 | } while (read_seqretry(&fastopen_seqlock, seq)); | |
781 | ||
782 | tfom = tfom_copy; | |
783 | if (tfom->mss && | |
784 | nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_MSS, | |
785 | tfom->mss) < 0) | |
786 | goto nla_put_failure; | |
787 | if (tfom->syn_loss && | |
788 | (nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_SYN_DROPS, | |
789 | tfom->syn_loss) < 0 || | |
790 | nla_put_msecs(msg, TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS, | |
791 | jiffies - tfom->last_syn_loss) < 0)) | |
792 | goto nla_put_failure; | |
793 | if (tfom->cookie.len > 0 && | |
794 | nla_put(msg, TCP_METRICS_ATTR_FOPEN_COOKIE, | |
795 | tfom->cookie.len, tfom->cookie.val) < 0) | |
796 | goto nla_put_failure; | |
797 | } | |
798 | ||
799 | return 0; | |
800 | ||
801 | nla_put_failure: | |
802 | return -EMSGSIZE; | |
803 | } | |
804 | ||
805 | static int tcp_metrics_dump_info(struct sk_buff *skb, | |
806 | struct netlink_callback *cb, | |
807 | struct tcp_metrics_block *tm) | |
808 | { | |
809 | void *hdr; | |
810 | ||
15e47304 | 811 | hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, |
d23ff701 JA |
812 | &tcp_metrics_nl_family, NLM_F_MULTI, |
813 | TCP_METRICS_CMD_GET); | |
814 | if (!hdr) | |
815 | return -EMSGSIZE; | |
816 | ||
817 | if (tcp_metrics_fill_info(skb, tm) < 0) | |
818 | goto nla_put_failure; | |
819 | ||
820 | return genlmsg_end(skb, hdr); | |
821 | ||
822 | nla_put_failure: | |
823 | genlmsg_cancel(skb, hdr); | |
824 | return -EMSGSIZE; | |
825 | } | |
826 | ||
827 | static int tcp_metrics_nl_dump(struct sk_buff *skb, | |
828 | struct netlink_callback *cb) | |
829 | { | |
830 | struct net *net = sock_net(skb->sk); | |
831 | unsigned int max_rows = 1U << net->ipv4.tcp_metrics_hash_log; | |
832 | unsigned int row, s_row = cb->args[0]; | |
833 | int s_col = cb->args[1], col = s_col; | |
834 | ||
835 | for (row = s_row; row < max_rows; row++, s_col = 0) { | |
836 | struct tcp_metrics_block *tm; | |
837 | struct tcpm_hash_bucket *hb = net->ipv4.tcp_metrics_hash + row; | |
838 | ||
839 | rcu_read_lock(); | |
840 | for (col = 0, tm = rcu_dereference(hb->chain); tm; | |
841 | tm = rcu_dereference(tm->tcpm_next), col++) { | |
842 | if (col < s_col) | |
843 | continue; | |
844 | if (tcp_metrics_dump_info(skb, cb, tm) < 0) { | |
845 | rcu_read_unlock(); | |
846 | goto done; | |
847 | } | |
848 | } | |
849 | rcu_read_unlock(); | |
850 | } | |
851 | ||
852 | done: | |
853 | cb->args[0] = row; | |
854 | cb->args[1] = col; | |
855 | return skb->len; | |
856 | } | |
857 | ||
858 | static int parse_nl_addr(struct genl_info *info, struct inetpeer_addr *addr, | |
859 | unsigned int *hash, int optional) | |
860 | { | |
861 | struct nlattr *a; | |
862 | ||
863 | a = info->attrs[TCP_METRICS_ATTR_ADDR_IPV4]; | |
864 | if (a) { | |
865 | addr->family = AF_INET; | |
866 | addr->addr.a4 = nla_get_be32(a); | |
867 | *hash = (__force unsigned int) addr->addr.a4; | |
868 | return 0; | |
869 | } | |
870 | a = info->attrs[TCP_METRICS_ATTR_ADDR_IPV6]; | |
871 | if (a) { | |
2c42a3fb | 872 | if (nla_len(a) != sizeof(struct in6_addr)) |
d23ff701 JA |
873 | return -EINVAL; |
874 | addr->family = AF_INET6; | |
875 | memcpy(addr->addr.a6, nla_data(a), sizeof(addr->addr.a6)); | |
876 | *hash = ipv6_addr_hash((struct in6_addr *) addr->addr.a6); | |
877 | return 0; | |
878 | } | |
879 | return optional ? 1 : -EAFNOSUPPORT; | |
880 | } | |
881 | ||
882 | static int tcp_metrics_nl_cmd_get(struct sk_buff *skb, struct genl_info *info) | |
883 | { | |
884 | struct tcp_metrics_block *tm; | |
885 | struct inetpeer_addr addr; | |
886 | unsigned int hash; | |
887 | struct sk_buff *msg; | |
888 | struct net *net = genl_info_net(info); | |
889 | void *reply; | |
890 | int ret; | |
891 | ||
892 | ret = parse_nl_addr(info, &addr, &hash, 0); | |
893 | if (ret < 0) | |
894 | return ret; | |
895 | ||
896 | msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); | |
897 | if (!msg) | |
898 | return -ENOMEM; | |
899 | ||
900 | reply = genlmsg_put_reply(msg, info, &tcp_metrics_nl_family, 0, | |
901 | info->genlhdr->cmd); | |
902 | if (!reply) | |
903 | goto nla_put_failure; | |
904 | ||
905 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); | |
906 | ret = -ESRCH; | |
907 | rcu_read_lock(); | |
908 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
909 | tm = rcu_dereference(tm->tcpm_next)) { | |
910 | if (addr_same(&tm->tcpm_addr, &addr)) { | |
911 | ret = tcp_metrics_fill_info(msg, tm); | |
912 | break; | |
913 | } | |
914 | } | |
915 | rcu_read_unlock(); | |
916 | if (ret < 0) | |
917 | goto out_free; | |
918 | ||
919 | genlmsg_end(msg, reply); | |
920 | return genlmsg_reply(msg, info); | |
921 | ||
922 | nla_put_failure: | |
923 | ret = -EMSGSIZE; | |
924 | ||
925 | out_free: | |
926 | nlmsg_free(msg); | |
927 | return ret; | |
928 | } | |
929 | ||
930 | #define deref_locked_genl(p) \ | |
931 | rcu_dereference_protected(p, lockdep_genl_is_held() && \ | |
932 | lockdep_is_held(&tcp_metrics_lock)) | |
933 | ||
934 | #define deref_genl(p) rcu_dereference_protected(p, lockdep_genl_is_held()) | |
935 | ||
936 | static int tcp_metrics_flush_all(struct net *net) | |
937 | { | |
938 | unsigned int max_rows = 1U << net->ipv4.tcp_metrics_hash_log; | |
939 | struct tcpm_hash_bucket *hb = net->ipv4.tcp_metrics_hash; | |
940 | struct tcp_metrics_block *tm; | |
941 | unsigned int row; | |
942 | ||
943 | for (row = 0; row < max_rows; row++, hb++) { | |
944 | spin_lock_bh(&tcp_metrics_lock); | |
945 | tm = deref_locked_genl(hb->chain); | |
946 | if (tm) | |
947 | hb->chain = NULL; | |
948 | spin_unlock_bh(&tcp_metrics_lock); | |
949 | while (tm) { | |
950 | struct tcp_metrics_block *next; | |
951 | ||
952 | next = deref_genl(tm->tcpm_next); | |
953 | kfree_rcu(tm, rcu_head); | |
954 | tm = next; | |
955 | } | |
956 | } | |
957 | return 0; | |
958 | } | |
959 | ||
960 | static int tcp_metrics_nl_cmd_del(struct sk_buff *skb, struct genl_info *info) | |
961 | { | |
962 | struct tcpm_hash_bucket *hb; | |
963 | struct tcp_metrics_block *tm; | |
964 | struct tcp_metrics_block __rcu **pp; | |
965 | struct inetpeer_addr addr; | |
966 | unsigned int hash; | |
967 | struct net *net = genl_info_net(info); | |
968 | int ret; | |
969 | ||
970 | ret = parse_nl_addr(info, &addr, &hash, 1); | |
971 | if (ret < 0) | |
972 | return ret; | |
973 | if (ret > 0) | |
974 | return tcp_metrics_flush_all(net); | |
975 | ||
976 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); | |
977 | hb = net->ipv4.tcp_metrics_hash + hash; | |
978 | pp = &hb->chain; | |
979 | spin_lock_bh(&tcp_metrics_lock); | |
980 | for (tm = deref_locked_genl(*pp); tm; | |
981 | pp = &tm->tcpm_next, tm = deref_locked_genl(*pp)) { | |
982 | if (addr_same(&tm->tcpm_addr, &addr)) { | |
983 | *pp = tm->tcpm_next; | |
984 | break; | |
985 | } | |
986 | } | |
987 | spin_unlock_bh(&tcp_metrics_lock); | |
988 | if (!tm) | |
989 | return -ESRCH; | |
990 | kfree_rcu(tm, rcu_head); | |
991 | return 0; | |
992 | } | |
993 | ||
4534de83 | 994 | static const struct genl_ops tcp_metrics_nl_ops[] = { |
d23ff701 JA |
995 | { |
996 | .cmd = TCP_METRICS_CMD_GET, | |
997 | .doit = tcp_metrics_nl_cmd_get, | |
998 | .dumpit = tcp_metrics_nl_dump, | |
999 | .policy = tcp_metrics_nl_policy, | |
1000 | .flags = GENL_ADMIN_PERM, | |
1001 | }, | |
1002 | { | |
1003 | .cmd = TCP_METRICS_CMD_DEL, | |
1004 | .doit = tcp_metrics_nl_cmd_del, | |
1005 | .policy = tcp_metrics_nl_policy, | |
1006 | .flags = GENL_ADMIN_PERM, | |
1007 | }, | |
1008 | }; | |
1009 | ||
5815d5e7 | 1010 | static unsigned int tcpmhash_entries; |
51c5d0c4 DM |
1011 | static int __init set_tcpmhash_entries(char *str) |
1012 | { | |
1013 | ssize_t ret; | |
1014 | ||
1015 | if (!str) | |
1016 | return 0; | |
1017 | ||
5815d5e7 | 1018 | ret = kstrtouint(str, 0, &tcpmhash_entries); |
51c5d0c4 DM |
1019 | if (ret) |
1020 | return 0; | |
1021 | ||
1022 | return 1; | |
1023 | } | |
1024 | __setup("tcpmhash_entries=", set_tcpmhash_entries); | |
1025 | ||
1026 | static int __net_init tcp_net_metrics_init(struct net *net) | |
1027 | { | |
5815d5e7 ED |
1028 | size_t size; |
1029 | unsigned int slots; | |
51c5d0c4 DM |
1030 | |
1031 | slots = tcpmhash_entries; | |
1032 | if (!slots) { | |
1033 | if (totalram_pages >= 128 * 1024) | |
1034 | slots = 16 * 1024; | |
1035 | else | |
1036 | slots = 8 * 1024; | |
1037 | } | |
1038 | ||
5815d5e7 ED |
1039 | net->ipv4.tcp_metrics_hash_log = order_base_2(slots); |
1040 | size = sizeof(struct tcpm_hash_bucket) << net->ipv4.tcp_metrics_hash_log; | |
51c5d0c4 | 1041 | |
976a702a ED |
1042 | net->ipv4.tcp_metrics_hash = kzalloc(size, GFP_KERNEL | __GFP_NOWARN); |
1043 | if (!net->ipv4.tcp_metrics_hash) | |
1044 | net->ipv4.tcp_metrics_hash = vzalloc(size); | |
1045 | ||
51c5d0c4 DM |
1046 | if (!net->ipv4.tcp_metrics_hash) |
1047 | return -ENOMEM; | |
1048 | ||
51c5d0c4 DM |
1049 | return 0; |
1050 | } | |
1051 | ||
1052 | static void __net_exit tcp_net_metrics_exit(struct net *net) | |
1053 | { | |
36471012 ED |
1054 | unsigned int i; |
1055 | ||
1056 | for (i = 0; i < (1U << net->ipv4.tcp_metrics_hash_log) ; i++) { | |
1057 | struct tcp_metrics_block *tm, *next; | |
1058 | ||
1059 | tm = rcu_dereference_protected(net->ipv4.tcp_metrics_hash[i].chain, 1); | |
1060 | while (tm) { | |
1061 | next = rcu_dereference_protected(tm->tcpm_next, 1); | |
1062 | kfree(tm); | |
1063 | tm = next; | |
1064 | } | |
1065 | } | |
976a702a ED |
1066 | if (is_vmalloc_addr(net->ipv4.tcp_metrics_hash)) |
1067 | vfree(net->ipv4.tcp_metrics_hash); | |
1068 | else | |
1069 | kfree(net->ipv4.tcp_metrics_hash); | |
51c5d0c4 DM |
1070 | } |
1071 | ||
1072 | static __net_initdata struct pernet_operations tcp_net_metrics_ops = { | |
1073 | .init = tcp_net_metrics_init, | |
1074 | .exit = tcp_net_metrics_exit, | |
1075 | }; | |
1076 | ||
1077 | void __init tcp_metrics_init(void) | |
1078 | { | |
d23ff701 JA |
1079 | int ret; |
1080 | ||
1081 | ret = register_pernet_subsys(&tcp_net_metrics_ops); | |
1082 | if (ret < 0) | |
1083 | goto cleanup; | |
1084 | ret = genl_register_family_with_ops(&tcp_metrics_nl_family, | |
c53ed742 | 1085 | tcp_metrics_nl_ops); |
d23ff701 JA |
1086 | if (ret < 0) |
1087 | goto cleanup_subsys; | |
1088 | return; | |
1089 | ||
1090 | cleanup_subsys: | |
1091 | unregister_pernet_subsys(&tcp_net_metrics_ops); | |
1092 | ||
1093 | cleanup: | |
1094 | return; | |
51c5d0c4 | 1095 | } |