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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 | ||
41804420 DM |
25 | static struct tcp_metrics_block *__tcp_get_metrics(const struct inetpeer_addr *saddr, |
26 | const struct inetpeer_addr *daddr, | |
77f99ad1 CP |
27 | struct net *net, unsigned int hash); |
28 | ||
1fe4c481 YC |
29 | struct tcp_fastopen_metrics { |
30 | u16 mss; | |
aab48743 YC |
31 | u16 syn_loss:10; /* Recurring Fast Open SYN losses */ |
32 | unsigned long last_syn_loss; /* Last Fast Open SYN loss */ | |
1fe4c481 YC |
33 | struct tcp_fastopen_cookie cookie; |
34 | }; | |
35 | ||
740b0f18 ED |
36 | /* TCP_METRIC_MAX includes 2 extra fields for userspace compatibility |
37 | * Kernel only stores RTT and RTTVAR in usec resolution | |
38 | */ | |
39 | #define TCP_METRIC_MAX_KERNEL (TCP_METRIC_MAX - 2) | |
40 | ||
51c5d0c4 DM |
41 | struct tcp_metrics_block { |
42 | struct tcp_metrics_block __rcu *tcpm_next; | |
a5443028 | 43 | struct inetpeer_addr tcpm_saddr; |
324fd55a | 44 | struct inetpeer_addr tcpm_daddr; |
51c5d0c4 | 45 | unsigned long tcpm_stamp; |
81166dd6 DM |
46 | u32 tcpm_ts; |
47 | u32 tcpm_ts_stamp; | |
51c5d0c4 | 48 | u32 tcpm_lock; |
740b0f18 | 49 | u32 tcpm_vals[TCP_METRIC_MAX_KERNEL + 1]; |
1fe4c481 | 50 | struct tcp_fastopen_metrics tcpm_fastopen; |
d23ff701 JA |
51 | |
52 | struct rcu_head rcu_head; | |
51c5d0c4 DM |
53 | }; |
54 | ||
55 | static bool tcp_metric_locked(struct tcp_metrics_block *tm, | |
56 | enum tcp_metric_index idx) | |
57 | { | |
58 | return tm->tcpm_lock & (1 << idx); | |
59 | } | |
60 | ||
61 | static u32 tcp_metric_get(struct tcp_metrics_block *tm, | |
62 | enum tcp_metric_index idx) | |
63 | { | |
64 | return tm->tcpm_vals[idx]; | |
65 | } | |
66 | ||
51c5d0c4 DM |
67 | static void tcp_metric_set(struct tcp_metrics_block *tm, |
68 | enum tcp_metric_index idx, | |
69 | u32 val) | |
70 | { | |
71 | tm->tcpm_vals[idx] = val; | |
72 | } | |
73 | ||
51c5d0c4 DM |
74 | static bool addr_same(const struct inetpeer_addr *a, |
75 | const struct inetpeer_addr *b) | |
76 | { | |
77 | const struct in6_addr *a6, *b6; | |
78 | ||
79 | if (a->family != b->family) | |
80 | return false; | |
81 | if (a->family == AF_INET) | |
82 | return a->addr.a4 == b->addr.a4; | |
83 | ||
84 | a6 = (const struct in6_addr *) &a->addr.a6[0]; | |
85 | b6 = (const struct in6_addr *) &b->addr.a6[0]; | |
86 | ||
87 | return ipv6_addr_equal(a6, b6); | |
88 | } | |
89 | ||
90 | struct tcpm_hash_bucket { | |
91 | struct tcp_metrics_block __rcu *chain; | |
92 | }; | |
93 | ||
94 | static DEFINE_SPINLOCK(tcp_metrics_lock); | |
95 | ||
740b0f18 ED |
96 | static void tcpm_suck_dst(struct tcp_metrics_block *tm, |
97 | const struct dst_entry *dst, | |
efeaa555 | 98 | bool fastopen_clear) |
51c5d0c4 | 99 | { |
740b0f18 | 100 | u32 msval; |
51c5d0c4 DM |
101 | u32 val; |
102 | ||
9a0a9502 JA |
103 | tm->tcpm_stamp = jiffies; |
104 | ||
51c5d0c4 DM |
105 | val = 0; |
106 | if (dst_metric_locked(dst, RTAX_RTT)) | |
107 | val |= 1 << TCP_METRIC_RTT; | |
108 | if (dst_metric_locked(dst, RTAX_RTTVAR)) | |
109 | val |= 1 << TCP_METRIC_RTTVAR; | |
110 | if (dst_metric_locked(dst, RTAX_SSTHRESH)) | |
111 | val |= 1 << TCP_METRIC_SSTHRESH; | |
112 | if (dst_metric_locked(dst, RTAX_CWND)) | |
113 | val |= 1 << TCP_METRIC_CWND; | |
114 | if (dst_metric_locked(dst, RTAX_REORDERING)) | |
115 | val |= 1 << TCP_METRIC_REORDERING; | |
116 | tm->tcpm_lock = val; | |
117 | ||
740b0f18 ED |
118 | msval = dst_metric_raw(dst, RTAX_RTT); |
119 | tm->tcpm_vals[TCP_METRIC_RTT] = msval * USEC_PER_MSEC; | |
120 | ||
121 | msval = dst_metric_raw(dst, RTAX_RTTVAR); | |
122 | tm->tcpm_vals[TCP_METRIC_RTTVAR] = msval * USEC_PER_MSEC; | |
51c5d0c4 DM |
123 | tm->tcpm_vals[TCP_METRIC_SSTHRESH] = dst_metric_raw(dst, RTAX_SSTHRESH); |
124 | tm->tcpm_vals[TCP_METRIC_CWND] = dst_metric_raw(dst, RTAX_CWND); | |
125 | tm->tcpm_vals[TCP_METRIC_REORDERING] = dst_metric_raw(dst, RTAX_REORDERING); | |
81166dd6 DM |
126 | tm->tcpm_ts = 0; |
127 | tm->tcpm_ts_stamp = 0; | |
efeaa555 ED |
128 | if (fastopen_clear) { |
129 | tm->tcpm_fastopen.mss = 0; | |
130 | tm->tcpm_fastopen.syn_loss = 0; | |
131 | tm->tcpm_fastopen.cookie.len = 0; | |
132 | } | |
51c5d0c4 DM |
133 | } |
134 | ||
77f99ad1 CP |
135 | #define TCP_METRICS_TIMEOUT (60 * 60 * HZ) |
136 | ||
137 | static void tcpm_check_stamp(struct tcp_metrics_block *tm, struct dst_entry *dst) | |
138 | { | |
139 | if (tm && unlikely(time_after(jiffies, tm->tcpm_stamp + TCP_METRICS_TIMEOUT))) | |
140 | tcpm_suck_dst(tm, dst, false); | |
141 | } | |
142 | ||
143 | #define TCP_METRICS_RECLAIM_DEPTH 5 | |
144 | #define TCP_METRICS_RECLAIM_PTR (struct tcp_metrics_block *) 0x1UL | |
145 | ||
51c5d0c4 | 146 | static struct tcp_metrics_block *tcpm_new(struct dst_entry *dst, |
a5443028 | 147 | struct inetpeer_addr *saddr, |
324fd55a | 148 | struct inetpeer_addr *daddr, |
77f99ad1 | 149 | unsigned int hash) |
51c5d0c4 DM |
150 | { |
151 | struct tcp_metrics_block *tm; | |
152 | struct net *net; | |
77f99ad1 | 153 | bool reclaim = false; |
51c5d0c4 DM |
154 | |
155 | spin_lock_bh(&tcp_metrics_lock); | |
156 | net = dev_net(dst->dev); | |
77f99ad1 CP |
157 | |
158 | /* While waiting for the spin-lock the cache might have been populated | |
159 | * with this entry and so we have to check again. | |
160 | */ | |
41804420 | 161 | tm = __tcp_get_metrics(saddr, daddr, net, hash); |
77f99ad1 CP |
162 | if (tm == TCP_METRICS_RECLAIM_PTR) { |
163 | reclaim = true; | |
164 | tm = NULL; | |
165 | } | |
166 | if (tm) { | |
167 | tcpm_check_stamp(tm, dst); | |
168 | goto out_unlock; | |
169 | } | |
170 | ||
51c5d0c4 DM |
171 | if (unlikely(reclaim)) { |
172 | struct tcp_metrics_block *oldest; | |
173 | ||
174 | oldest = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); | |
175 | for (tm = rcu_dereference(oldest->tcpm_next); tm; | |
176 | tm = rcu_dereference(tm->tcpm_next)) { | |
177 | if (time_before(tm->tcpm_stamp, oldest->tcpm_stamp)) | |
178 | oldest = tm; | |
179 | } | |
180 | tm = oldest; | |
181 | } else { | |
182 | tm = kmalloc(sizeof(*tm), GFP_ATOMIC); | |
183 | if (!tm) | |
184 | goto out_unlock; | |
185 | } | |
a5443028 | 186 | tm->tcpm_saddr = *saddr; |
324fd55a | 187 | tm->tcpm_daddr = *daddr; |
51c5d0c4 | 188 | |
efeaa555 | 189 | tcpm_suck_dst(tm, dst, true); |
51c5d0c4 DM |
190 | |
191 | if (likely(!reclaim)) { | |
192 | tm->tcpm_next = net->ipv4.tcp_metrics_hash[hash].chain; | |
193 | rcu_assign_pointer(net->ipv4.tcp_metrics_hash[hash].chain, tm); | |
194 | } | |
195 | ||
196 | out_unlock: | |
197 | spin_unlock_bh(&tcp_metrics_lock); | |
198 | return tm; | |
199 | } | |
200 | ||
51c5d0c4 DM |
201 | static struct tcp_metrics_block *tcp_get_encode(struct tcp_metrics_block *tm, int depth) |
202 | { | |
203 | if (tm) | |
204 | return tm; | |
205 | if (depth > TCP_METRICS_RECLAIM_DEPTH) | |
206 | return TCP_METRICS_RECLAIM_PTR; | |
207 | return NULL; | |
208 | } | |
209 | ||
a5443028 CP |
210 | static struct tcp_metrics_block *__tcp_get_metrics(const struct inetpeer_addr *saddr, |
211 | const struct inetpeer_addr *daddr, | |
51c5d0c4 DM |
212 | struct net *net, unsigned int hash) |
213 | { | |
214 | struct tcp_metrics_block *tm; | |
215 | int depth = 0; | |
216 | ||
217 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
218 | tm = rcu_dereference(tm->tcpm_next)) { | |
a5443028 CP |
219 | if (addr_same(&tm->tcpm_saddr, saddr) && |
220 | addr_same(&tm->tcpm_daddr, daddr)) | |
51c5d0c4 DM |
221 | break; |
222 | depth++; | |
223 | } | |
224 | return tcp_get_encode(tm, depth); | |
225 | } | |
226 | ||
227 | static struct tcp_metrics_block *__tcp_get_metrics_req(struct request_sock *req, | |
228 | struct dst_entry *dst) | |
229 | { | |
230 | struct tcp_metrics_block *tm; | |
a5443028 | 231 | struct inetpeer_addr saddr, daddr; |
51c5d0c4 DM |
232 | unsigned int hash; |
233 | struct net *net; | |
234 | ||
a5443028 | 235 | saddr.family = req->rsk_ops->family; |
324fd55a CP |
236 | daddr.family = req->rsk_ops->family; |
237 | switch (daddr.family) { | |
51c5d0c4 | 238 | case AF_INET: |
a5443028 | 239 | saddr.addr.a4 = inet_rsk(req)->ir_loc_addr; |
324fd55a CP |
240 | daddr.addr.a4 = inet_rsk(req)->ir_rmt_addr; |
241 | hash = (__force unsigned int) daddr.addr.a4; | |
51c5d0c4 | 242 | break; |
634fb979 | 243 | #if IS_ENABLED(CONFIG_IPV6) |
51c5d0c4 | 244 | case AF_INET6: |
a5443028 | 245 | *(struct in6_addr *)saddr.addr.a6 = inet_rsk(req)->ir_v6_loc_addr; |
324fd55a | 246 | *(struct in6_addr *)daddr.addr.a6 = inet_rsk(req)->ir_v6_rmt_addr; |
634fb979 | 247 | hash = ipv6_addr_hash(&inet_rsk(req)->ir_v6_rmt_addr); |
51c5d0c4 | 248 | break; |
634fb979 | 249 | #endif |
51c5d0c4 DM |
250 | default: |
251 | return NULL; | |
252 | } | |
253 | ||
51c5d0c4 | 254 | net = dev_net(dst->dev); |
5815d5e7 | 255 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
51c5d0c4 DM |
256 | |
257 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
258 | tm = rcu_dereference(tm->tcpm_next)) { | |
a5443028 CP |
259 | if (addr_same(&tm->tcpm_saddr, &saddr) && |
260 | addr_same(&tm->tcpm_daddr, &daddr)) | |
51c5d0c4 DM |
261 | break; |
262 | } | |
263 | tcpm_check_stamp(tm, dst); | |
264 | return tm; | |
265 | } | |
266 | ||
81166dd6 DM |
267 | static struct tcp_metrics_block *__tcp_get_metrics_tw(struct inet_timewait_sock *tw) |
268 | { | |
81166dd6 | 269 | struct tcp_metrics_block *tm; |
a5443028 | 270 | struct inetpeer_addr saddr, daddr; |
81166dd6 DM |
271 | unsigned int hash; |
272 | struct net *net; | |
273 | ||
3ad88cf7 CP |
274 | if (tw->tw_family == AF_INET) { |
275 | saddr.family = AF_INET; | |
a5443028 | 276 | saddr.addr.a4 = tw->tw_rcv_saddr; |
3ad88cf7 | 277 | daddr.family = AF_INET; |
324fd55a CP |
278 | daddr.addr.a4 = tw->tw_daddr; |
279 | hash = (__force unsigned int) daddr.addr.a4; | |
3ad88cf7 | 280 | } |
c2bb06db | 281 | #if IS_ENABLED(CONFIG_IPV6) |
3ad88cf7 CP |
282 | else if (tw->tw_family == AF_INET6) { |
283 | if (ipv6_addr_v4mapped(&tw->tw_v6_daddr)) { | |
284 | saddr.family = AF_INET; | |
285 | saddr.addr.a4 = tw->tw_rcv_saddr; | |
286 | daddr.family = AF_INET; | |
287 | daddr.addr.a4 = tw->tw_daddr; | |
288 | hash = (__force unsigned int) daddr.addr.a4; | |
289 | } else { | |
290 | saddr.family = AF_INET6; | |
291 | *(struct in6_addr *)saddr.addr.a6 = tw->tw_v6_rcv_saddr; | |
292 | daddr.family = AF_INET6; | |
293 | *(struct in6_addr *)daddr.addr.a6 = tw->tw_v6_daddr; | |
294 | hash = ipv6_addr_hash(&tw->tw_v6_daddr); | |
295 | } | |
296 | } | |
c2bb06db | 297 | #endif |
3ad88cf7 | 298 | else |
81166dd6 | 299 | return NULL; |
81166dd6 | 300 | |
81166dd6 | 301 | net = twsk_net(tw); |
5815d5e7 | 302 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
81166dd6 DM |
303 | |
304 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
305 | tm = rcu_dereference(tm->tcpm_next)) { | |
a5443028 CP |
306 | if (addr_same(&tm->tcpm_saddr, &saddr) && |
307 | addr_same(&tm->tcpm_daddr, &daddr)) | |
81166dd6 DM |
308 | break; |
309 | } | |
310 | return tm; | |
311 | } | |
312 | ||
51c5d0c4 DM |
313 | static struct tcp_metrics_block *tcp_get_metrics(struct sock *sk, |
314 | struct dst_entry *dst, | |
315 | bool create) | |
316 | { | |
317 | struct tcp_metrics_block *tm; | |
a5443028 | 318 | struct inetpeer_addr saddr, daddr; |
51c5d0c4 DM |
319 | unsigned int hash; |
320 | struct net *net; | |
51c5d0c4 | 321 | |
3ad88cf7 CP |
322 | if (sk->sk_family == AF_INET) { |
323 | saddr.family = AF_INET; | |
a5443028 | 324 | saddr.addr.a4 = inet_sk(sk)->inet_saddr; |
3ad88cf7 | 325 | daddr.family = AF_INET; |
324fd55a CP |
326 | daddr.addr.a4 = inet_sk(sk)->inet_daddr; |
327 | hash = (__force unsigned int) daddr.addr.a4; | |
3ad88cf7 | 328 | } |
c2bb06db | 329 | #if IS_ENABLED(CONFIG_IPV6) |
3ad88cf7 CP |
330 | else if (sk->sk_family == AF_INET6) { |
331 | if (ipv6_addr_v4mapped(&sk->sk_v6_daddr)) { | |
332 | saddr.family = AF_INET; | |
333 | saddr.addr.a4 = inet_sk(sk)->inet_saddr; | |
334 | daddr.family = AF_INET; | |
335 | daddr.addr.a4 = inet_sk(sk)->inet_daddr; | |
336 | hash = (__force unsigned int) daddr.addr.a4; | |
337 | } else { | |
338 | saddr.family = AF_INET6; | |
339 | *(struct in6_addr *)saddr.addr.a6 = sk->sk_v6_rcv_saddr; | |
340 | daddr.family = AF_INET6; | |
341 | *(struct in6_addr *)daddr.addr.a6 = sk->sk_v6_daddr; | |
342 | hash = ipv6_addr_hash(&sk->sk_v6_daddr); | |
343 | } | |
344 | } | |
c2bb06db | 345 | #endif |
3ad88cf7 | 346 | else |
51c5d0c4 | 347 | return NULL; |
51c5d0c4 | 348 | |
51c5d0c4 | 349 | net = dev_net(dst->dev); |
5815d5e7 | 350 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
51c5d0c4 | 351 | |
a5443028 | 352 | tm = __tcp_get_metrics(&saddr, &daddr, net, hash); |
77f99ad1 | 353 | if (tm == TCP_METRICS_RECLAIM_PTR) |
51c5d0c4 | 354 | tm = NULL; |
51c5d0c4 | 355 | if (!tm && create) |
41804420 | 356 | tm = tcpm_new(dst, &saddr, &daddr, hash); |
51c5d0c4 DM |
357 | else |
358 | tcpm_check_stamp(tm, dst); | |
359 | ||
360 | return tm; | |
361 | } | |
362 | ||
4aabd8ef DM |
363 | /* Save metrics learned by this TCP session. This function is called |
364 | * only, when TCP finishes successfully i.e. when it enters TIME-WAIT | |
365 | * or goes from LAST-ACK to CLOSE. | |
366 | */ | |
367 | void tcp_update_metrics(struct sock *sk) | |
368 | { | |
51c5d0c4 | 369 | const struct inet_connection_sock *icsk = inet_csk(sk); |
4aabd8ef | 370 | struct dst_entry *dst = __sk_dst_get(sk); |
51c5d0c4 DM |
371 | struct tcp_sock *tp = tcp_sk(sk); |
372 | struct tcp_metrics_block *tm; | |
373 | unsigned long rtt; | |
374 | u32 val; | |
375 | int m; | |
4aabd8ef | 376 | |
51c5d0c4 | 377 | if (sysctl_tcp_nometrics_save || !dst) |
4aabd8ef DM |
378 | return; |
379 | ||
51c5d0c4 | 380 | if (dst->flags & DST_HOST) |
4aabd8ef DM |
381 | dst_confirm(dst); |
382 | ||
51c5d0c4 | 383 | rcu_read_lock(); |
740b0f18 | 384 | if (icsk->icsk_backoff || !tp->srtt_us) { |
51c5d0c4 DM |
385 | /* This session failed to estimate rtt. Why? |
386 | * Probably, no packets returned in time. Reset our | |
387 | * results. | |
388 | */ | |
389 | tm = tcp_get_metrics(sk, dst, false); | |
390 | if (tm && !tcp_metric_locked(tm, TCP_METRIC_RTT)) | |
391 | tcp_metric_set(tm, TCP_METRIC_RTT, 0); | |
392 | goto out_unlock; | |
393 | } else | |
394 | tm = tcp_get_metrics(sk, dst, true); | |
4aabd8ef | 395 | |
51c5d0c4 DM |
396 | if (!tm) |
397 | goto out_unlock; | |
4aabd8ef | 398 | |
740b0f18 ED |
399 | rtt = tcp_metric_get(tm, TCP_METRIC_RTT); |
400 | m = rtt - tp->srtt_us; | |
4aabd8ef | 401 | |
51c5d0c4 DM |
402 | /* If newly calculated rtt larger than stored one, store new |
403 | * one. Otherwise, use EWMA. Remember, rtt overestimation is | |
404 | * always better than underestimation. | |
405 | */ | |
406 | if (!tcp_metric_locked(tm, TCP_METRIC_RTT)) { | |
407 | if (m <= 0) | |
740b0f18 | 408 | rtt = tp->srtt_us; |
51c5d0c4 DM |
409 | else |
410 | rtt -= (m >> 3); | |
740b0f18 | 411 | tcp_metric_set(tm, TCP_METRIC_RTT, rtt); |
51c5d0c4 | 412 | } |
4aabd8ef | 413 | |
51c5d0c4 DM |
414 | if (!tcp_metric_locked(tm, TCP_METRIC_RTTVAR)) { |
415 | unsigned long var; | |
4aabd8ef | 416 | |
51c5d0c4 DM |
417 | if (m < 0) |
418 | m = -m; | |
4aabd8ef | 419 | |
51c5d0c4 DM |
420 | /* Scale deviation to rttvar fixed point */ |
421 | m >>= 1; | |
740b0f18 ED |
422 | if (m < tp->mdev_us) |
423 | m = tp->mdev_us; | |
4aabd8ef | 424 | |
740b0f18 | 425 | var = tcp_metric_get(tm, TCP_METRIC_RTTVAR); |
51c5d0c4 DM |
426 | if (m >= var) |
427 | var = m; | |
428 | else | |
429 | var -= (var - m) >> 2; | |
4aabd8ef | 430 | |
740b0f18 | 431 | tcp_metric_set(tm, TCP_METRIC_RTTVAR, var); |
51c5d0c4 DM |
432 | } |
433 | ||
434 | if (tcp_in_initial_slowstart(tp)) { | |
435 | /* Slow start still did not finish. */ | |
436 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) { | |
437 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
438 | if (val && (tp->snd_cwnd >> 1) > val) | |
439 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, | |
440 | tp->snd_cwnd >> 1); | |
441 | } | |
442 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { | |
443 | val = tcp_metric_get(tm, TCP_METRIC_CWND); | |
444 | if (tp->snd_cwnd > val) | |
445 | tcp_metric_set(tm, TCP_METRIC_CWND, | |
446 | tp->snd_cwnd); | |
447 | } | |
448 | } else if (tp->snd_cwnd > tp->snd_ssthresh && | |
449 | icsk->icsk_ca_state == TCP_CA_Open) { | |
450 | /* Cong. avoidance phase, cwnd is reliable. */ | |
451 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) | |
452 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, | |
453 | max(tp->snd_cwnd >> 1, tp->snd_ssthresh)); | |
454 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { | |
455 | val = tcp_metric_get(tm, TCP_METRIC_CWND); | |
2100844c | 456 | tcp_metric_set(tm, TCP_METRIC_CWND, (val + tp->snd_cwnd) >> 1); |
51c5d0c4 DM |
457 | } |
458 | } else { | |
459 | /* Else slow start did not finish, cwnd is non-sense, | |
460 | * ssthresh may be also invalid. | |
461 | */ | |
462 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { | |
463 | val = tcp_metric_get(tm, TCP_METRIC_CWND); | |
464 | tcp_metric_set(tm, TCP_METRIC_CWND, | |
465 | (val + tp->snd_ssthresh) >> 1); | |
466 | } | |
467 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) { | |
468 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
469 | if (val && tp->snd_ssthresh > val) | |
470 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, | |
471 | tp->snd_ssthresh); | |
472 | } | |
473 | if (!tcp_metric_locked(tm, TCP_METRIC_REORDERING)) { | |
474 | val = tcp_metric_get(tm, TCP_METRIC_REORDERING); | |
475 | if (val < tp->reordering && | |
4aabd8ef | 476 | tp->reordering != sysctl_tcp_reordering) |
51c5d0c4 DM |
477 | tcp_metric_set(tm, TCP_METRIC_REORDERING, |
478 | tp->reordering); | |
4aabd8ef DM |
479 | } |
480 | } | |
51c5d0c4 DM |
481 | tm->tcpm_stamp = jiffies; |
482 | out_unlock: | |
483 | rcu_read_unlock(); | |
4aabd8ef DM |
484 | } |
485 | ||
486 | /* Initialize metrics on socket. */ | |
487 | ||
488 | void tcp_init_metrics(struct sock *sk) | |
489 | { | |
4aabd8ef | 490 | struct dst_entry *dst = __sk_dst_get(sk); |
51c5d0c4 DM |
491 | struct tcp_sock *tp = tcp_sk(sk); |
492 | struct tcp_metrics_block *tm; | |
1b7fdd2a | 493 | u32 val, crtt = 0; /* cached RTT scaled by 8 */ |
4aabd8ef DM |
494 | |
495 | if (dst == NULL) | |
496 | goto reset; | |
497 | ||
498 | dst_confirm(dst); | |
499 | ||
51c5d0c4 DM |
500 | rcu_read_lock(); |
501 | tm = tcp_get_metrics(sk, dst, true); | |
502 | if (!tm) { | |
503 | rcu_read_unlock(); | |
504 | goto reset; | |
505 | } | |
506 | ||
507 | if (tcp_metric_locked(tm, TCP_METRIC_CWND)) | |
508 | tp->snd_cwnd_clamp = tcp_metric_get(tm, TCP_METRIC_CWND); | |
509 | ||
510 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); | |
511 | if (val) { | |
512 | tp->snd_ssthresh = val; | |
4aabd8ef DM |
513 | if (tp->snd_ssthresh > tp->snd_cwnd_clamp) |
514 | tp->snd_ssthresh = tp->snd_cwnd_clamp; | |
515 | } else { | |
516 | /* ssthresh may have been reduced unnecessarily during. | |
517 | * 3WHS. Restore it back to its initial default. | |
518 | */ | |
519 | tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; | |
520 | } | |
51c5d0c4 DM |
521 | val = tcp_metric_get(tm, TCP_METRIC_REORDERING); |
522 | if (val && tp->reordering != val) { | |
4aabd8ef DM |
523 | tcp_disable_fack(tp); |
524 | tcp_disable_early_retrans(tp); | |
51c5d0c4 | 525 | tp->reordering = val; |
4aabd8ef DM |
526 | } |
527 | ||
740b0f18 | 528 | crtt = tcp_metric_get(tm, TCP_METRIC_RTT); |
51c5d0c4 | 529 | rcu_read_unlock(); |
4aabd8ef | 530 | reset: |
52f20e65 YC |
531 | /* The initial RTT measurement from the SYN/SYN-ACK is not ideal |
532 | * to seed the RTO for later data packets because SYN packets are | |
533 | * small. Use the per-dst cached values to seed the RTO but keep | |
534 | * the RTT estimator variables intact (e.g., srtt, mdev, rttvar). | |
535 | * Later the RTO will be updated immediately upon obtaining the first | |
536 | * data RTT sample (tcp_rtt_estimator()). Hence the cached RTT only | |
537 | * influences the first RTO but not later RTT estimation. | |
538 | * | |
539 | * But if RTT is not available from the SYN (due to retransmits or | |
540 | * syn cookies) or the cache, force a conservative 3secs timeout. | |
541 | * | |
542 | * A bit of theory. RTT is time passed after "normal" sized packet | |
543 | * is sent until it is ACKed. In normal circumstances sending small | |
544 | * packets force peer to delay ACKs and calculation is correct too. | |
545 | * The algorithm is adaptive and, provided we follow specs, it | |
546 | * NEVER underestimate RTT. BUT! If peer tries to make some clever | |
547 | * tricks sort of "quick acks" for time long enough to decrease RTT | |
548 | * to low value, and then abruptly stops to do it and starts to delay | |
549 | * ACKs, wait for troubles. | |
550 | */ | |
740b0f18 | 551 | if (crtt > tp->srtt_us) { |
269aa759 | 552 | /* Set RTO like tcp_rtt_estimator(), but from cached RTT. */ |
740b0f18 | 553 | crtt /= 8 * USEC_PER_MSEC; |
269aa759 | 554 | inet_csk(sk)->icsk_rto = crtt + max(2 * crtt, tcp_rto_min(sk)); |
740b0f18 | 555 | } else if (tp->srtt_us == 0) { |
4aabd8ef DM |
556 | /* RFC6298: 5.7 We've failed to get a valid RTT sample from |
557 | * 3WHS. This is most likely due to retransmission, | |
558 | * including spurious one. Reset the RTO back to 3secs | |
559 | * from the more aggressive 1sec to avoid more spurious | |
560 | * retransmission. | |
561 | */ | |
740b0f18 ED |
562 | tp->rttvar_us = jiffies_to_usecs(TCP_TIMEOUT_FALLBACK); |
563 | tp->mdev_us = tp->mdev_max_us = tp->rttvar_us; | |
564 | ||
4aabd8ef DM |
565 | inet_csk(sk)->icsk_rto = TCP_TIMEOUT_FALLBACK; |
566 | } | |
567 | /* Cut cwnd down to 1 per RFC5681 if SYN or SYN-ACK has been | |
568 | * retransmitted. In light of RFC6298 more aggressive 1sec | |
569 | * initRTO, we only reset cwnd when more than 1 SYN/SYN-ACK | |
570 | * retransmission has occurred. | |
571 | */ | |
572 | if (tp->total_retrans > 1) | |
573 | tp->snd_cwnd = 1; | |
574 | else | |
575 | tp->snd_cwnd = tcp_init_cwnd(tp, dst); | |
576 | tp->snd_cwnd_stamp = tcp_time_stamp; | |
577 | } | |
ab92bb2f | 578 | |
a26552af HFS |
579 | bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst, |
580 | bool paws_check, bool timestamps) | |
ab92bb2f | 581 | { |
51c5d0c4 DM |
582 | struct tcp_metrics_block *tm; |
583 | bool ret; | |
584 | ||
ab92bb2f DM |
585 | if (!dst) |
586 | return false; | |
51c5d0c4 DM |
587 | |
588 | rcu_read_lock(); | |
589 | tm = __tcp_get_metrics_req(req, dst); | |
81166dd6 DM |
590 | if (paws_check) { |
591 | if (tm && | |
592 | (u32)get_seconds() - tm->tcpm_ts_stamp < TCP_PAWS_MSL && | |
a26552af HFS |
593 | ((s32)(tm->tcpm_ts - req->ts_recent) > TCP_PAWS_WINDOW || |
594 | !timestamps)) | |
81166dd6 DM |
595 | ret = false; |
596 | else | |
597 | ret = true; | |
598 | } else { | |
599 | if (tm && tcp_metric_get(tm, TCP_METRIC_RTT) && tm->tcpm_ts_stamp) | |
600 | ret = true; | |
601 | else | |
602 | ret = false; | |
603 | } | |
51c5d0c4 DM |
604 | rcu_read_unlock(); |
605 | ||
606 | return ret; | |
ab92bb2f DM |
607 | } |
608 | EXPORT_SYMBOL_GPL(tcp_peer_is_proven); | |
51c5d0c4 | 609 | |
81166dd6 DM |
610 | void tcp_fetch_timewait_stamp(struct sock *sk, struct dst_entry *dst) |
611 | { | |
612 | struct tcp_metrics_block *tm; | |
613 | ||
614 | rcu_read_lock(); | |
615 | tm = tcp_get_metrics(sk, dst, true); | |
616 | if (tm) { | |
617 | struct tcp_sock *tp = tcp_sk(sk); | |
618 | ||
619 | if ((u32)get_seconds() - tm->tcpm_ts_stamp <= TCP_PAWS_MSL) { | |
620 | tp->rx_opt.ts_recent_stamp = tm->tcpm_ts_stamp; | |
621 | tp->rx_opt.ts_recent = tm->tcpm_ts; | |
622 | } | |
623 | } | |
624 | rcu_read_unlock(); | |
625 | } | |
626 | EXPORT_SYMBOL_GPL(tcp_fetch_timewait_stamp); | |
627 | ||
628 | /* VJ's idea. Save last timestamp seen from this destination and hold | |
629 | * it at least for normal timewait interval to use for duplicate | |
630 | * segment detection in subsequent connections, before they enter | |
631 | * synchronized state. | |
632 | */ | |
633 | bool tcp_remember_stamp(struct sock *sk) | |
634 | { | |
635 | struct dst_entry *dst = __sk_dst_get(sk); | |
636 | bool ret = false; | |
637 | ||
638 | if (dst) { | |
639 | struct tcp_metrics_block *tm; | |
640 | ||
641 | rcu_read_lock(); | |
642 | tm = tcp_get_metrics(sk, dst, true); | |
643 | if (tm) { | |
644 | struct tcp_sock *tp = tcp_sk(sk); | |
645 | ||
646 | if ((s32)(tm->tcpm_ts - tp->rx_opt.ts_recent) <= 0 || | |
647 | ((u32)get_seconds() - tm->tcpm_ts_stamp > TCP_PAWS_MSL && | |
648 | tm->tcpm_ts_stamp <= (u32)tp->rx_opt.ts_recent_stamp)) { | |
649 | tm->tcpm_ts_stamp = (u32)tp->rx_opt.ts_recent_stamp; | |
650 | tm->tcpm_ts = tp->rx_opt.ts_recent; | |
651 | } | |
652 | ret = true; | |
653 | } | |
654 | rcu_read_unlock(); | |
655 | } | |
656 | return ret; | |
657 | } | |
658 | ||
659 | bool tcp_tw_remember_stamp(struct inet_timewait_sock *tw) | |
660 | { | |
661 | struct tcp_metrics_block *tm; | |
662 | bool ret = false; | |
663 | ||
664 | rcu_read_lock(); | |
665 | tm = __tcp_get_metrics_tw(tw); | |
9a0a9502 | 666 | if (tm) { |
81166dd6 DM |
667 | const struct tcp_timewait_sock *tcptw; |
668 | struct sock *sk = (struct sock *) tw; | |
669 | ||
670 | tcptw = tcp_twsk(sk); | |
671 | if ((s32)(tm->tcpm_ts - tcptw->tw_ts_recent) <= 0 || | |
672 | ((u32)get_seconds() - tm->tcpm_ts_stamp > TCP_PAWS_MSL && | |
673 | tm->tcpm_ts_stamp <= (u32)tcptw->tw_ts_recent_stamp)) { | |
674 | tm->tcpm_ts_stamp = (u32)tcptw->tw_ts_recent_stamp; | |
675 | tm->tcpm_ts = tcptw->tw_ts_recent; | |
676 | } | |
677 | ret = true; | |
678 | } | |
679 | rcu_read_unlock(); | |
680 | ||
681 | return ret; | |
682 | } | |
683 | ||
1fe4c481 YC |
684 | static DEFINE_SEQLOCK(fastopen_seqlock); |
685 | ||
686 | void tcp_fastopen_cache_get(struct sock *sk, u16 *mss, | |
aab48743 YC |
687 | struct tcp_fastopen_cookie *cookie, |
688 | int *syn_loss, unsigned long *last_syn_loss) | |
1fe4c481 YC |
689 | { |
690 | struct tcp_metrics_block *tm; | |
691 | ||
692 | rcu_read_lock(); | |
693 | tm = tcp_get_metrics(sk, __sk_dst_get(sk), false); | |
694 | if (tm) { | |
695 | struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; | |
696 | unsigned int seq; | |
697 | ||
698 | do { | |
699 | seq = read_seqbegin(&fastopen_seqlock); | |
700 | if (tfom->mss) | |
701 | *mss = tfom->mss; | |
702 | *cookie = tfom->cookie; | |
aab48743 YC |
703 | *syn_loss = tfom->syn_loss; |
704 | *last_syn_loss = *syn_loss ? tfom->last_syn_loss : 0; | |
1fe4c481 YC |
705 | } while (read_seqretry(&fastopen_seqlock, seq)); |
706 | } | |
707 | rcu_read_unlock(); | |
708 | } | |
709 | ||
1fe4c481 | 710 | void tcp_fastopen_cache_set(struct sock *sk, u16 mss, |
aab48743 | 711 | struct tcp_fastopen_cookie *cookie, bool syn_lost) |
1fe4c481 | 712 | { |
dccf76ca | 713 | struct dst_entry *dst = __sk_dst_get(sk); |
1fe4c481 YC |
714 | struct tcp_metrics_block *tm; |
715 | ||
dccf76ca ED |
716 | if (!dst) |
717 | return; | |
1fe4c481 | 718 | rcu_read_lock(); |
dccf76ca | 719 | tm = tcp_get_metrics(sk, dst, true); |
1fe4c481 YC |
720 | if (tm) { |
721 | struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; | |
722 | ||
723 | write_seqlock_bh(&fastopen_seqlock); | |
c968601d YC |
724 | if (mss) |
725 | tfom->mss = mss; | |
726 | if (cookie && cookie->len > 0) | |
1fe4c481 | 727 | tfom->cookie = *cookie; |
aab48743 YC |
728 | if (syn_lost) { |
729 | ++tfom->syn_loss; | |
730 | tfom->last_syn_loss = jiffies; | |
731 | } else | |
732 | tfom->syn_loss = 0; | |
1fe4c481 YC |
733 | write_sequnlock_bh(&fastopen_seqlock); |
734 | } | |
735 | rcu_read_unlock(); | |
736 | } | |
737 | ||
d23ff701 JA |
738 | static struct genl_family tcp_metrics_nl_family = { |
739 | .id = GENL_ID_GENERATE, | |
740 | .hdrsize = 0, | |
741 | .name = TCP_METRICS_GENL_NAME, | |
742 | .version = TCP_METRICS_GENL_VERSION, | |
743 | .maxattr = TCP_METRICS_ATTR_MAX, | |
744 | .netnsok = true, | |
745 | }; | |
746 | ||
747 | static struct nla_policy tcp_metrics_nl_policy[TCP_METRICS_ATTR_MAX + 1] = { | |
748 | [TCP_METRICS_ATTR_ADDR_IPV4] = { .type = NLA_U32, }, | |
749 | [TCP_METRICS_ATTR_ADDR_IPV6] = { .type = NLA_BINARY, | |
750 | .len = sizeof(struct in6_addr), }, | |
751 | /* Following attributes are not received for GET/DEL, | |
752 | * we keep them for reference | |
753 | */ | |
754 | #if 0 | |
755 | [TCP_METRICS_ATTR_AGE] = { .type = NLA_MSECS, }, | |
756 | [TCP_METRICS_ATTR_TW_TSVAL] = { .type = NLA_U32, }, | |
757 | [TCP_METRICS_ATTR_TW_TS_STAMP] = { .type = NLA_S32, }, | |
758 | [TCP_METRICS_ATTR_VALS] = { .type = NLA_NESTED, }, | |
759 | [TCP_METRICS_ATTR_FOPEN_MSS] = { .type = NLA_U16, }, | |
760 | [TCP_METRICS_ATTR_FOPEN_SYN_DROPS] = { .type = NLA_U16, }, | |
761 | [TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS] = { .type = NLA_MSECS, }, | |
762 | [TCP_METRICS_ATTR_FOPEN_COOKIE] = { .type = NLA_BINARY, | |
763 | .len = TCP_FASTOPEN_COOKIE_MAX, }, | |
764 | #endif | |
765 | }; | |
766 | ||
767 | /* Add attributes, caller cancels its header on failure */ | |
768 | static int tcp_metrics_fill_info(struct sk_buff *msg, | |
769 | struct tcp_metrics_block *tm) | |
770 | { | |
771 | struct nlattr *nest; | |
772 | int i; | |
773 | ||
324fd55a | 774 | switch (tm->tcpm_daddr.family) { |
d23ff701 JA |
775 | case AF_INET: |
776 | if (nla_put_be32(msg, TCP_METRICS_ATTR_ADDR_IPV4, | |
324fd55a | 777 | tm->tcpm_daddr.addr.a4) < 0) |
d23ff701 | 778 | goto nla_put_failure; |
8a59359c CP |
779 | if (nla_put_be32(msg, TCP_METRICS_ATTR_SADDR_IPV4, |
780 | tm->tcpm_saddr.addr.a4) < 0) | |
781 | goto nla_put_failure; | |
d23ff701 JA |
782 | break; |
783 | case AF_INET6: | |
784 | if (nla_put(msg, TCP_METRICS_ATTR_ADDR_IPV6, 16, | |
324fd55a | 785 | tm->tcpm_daddr.addr.a6) < 0) |
d23ff701 | 786 | goto nla_put_failure; |
8a59359c CP |
787 | if (nla_put(msg, TCP_METRICS_ATTR_SADDR_IPV6, 16, |
788 | tm->tcpm_saddr.addr.a6) < 0) | |
789 | goto nla_put_failure; | |
d23ff701 JA |
790 | break; |
791 | default: | |
792 | return -EAFNOSUPPORT; | |
793 | } | |
794 | ||
795 | if (nla_put_msecs(msg, TCP_METRICS_ATTR_AGE, | |
796 | jiffies - tm->tcpm_stamp) < 0) | |
797 | goto nla_put_failure; | |
798 | if (tm->tcpm_ts_stamp) { | |
799 | if (nla_put_s32(msg, TCP_METRICS_ATTR_TW_TS_STAMP, | |
800 | (s32) (get_seconds() - tm->tcpm_ts_stamp)) < 0) | |
801 | goto nla_put_failure; | |
802 | if (nla_put_u32(msg, TCP_METRICS_ATTR_TW_TSVAL, | |
803 | tm->tcpm_ts) < 0) | |
804 | goto nla_put_failure; | |
805 | } | |
806 | ||
807 | { | |
808 | int n = 0; | |
809 | ||
810 | nest = nla_nest_start(msg, TCP_METRICS_ATTR_VALS); | |
811 | if (!nest) | |
812 | goto nla_put_failure; | |
740b0f18 ED |
813 | for (i = 0; i < TCP_METRIC_MAX_KERNEL + 1; i++) { |
814 | u32 val = tm->tcpm_vals[i]; | |
815 | ||
816 | if (!val) | |
d23ff701 | 817 | continue; |
740b0f18 ED |
818 | if (i == TCP_METRIC_RTT) { |
819 | if (nla_put_u32(msg, TCP_METRIC_RTT_US + 1, | |
820 | val) < 0) | |
821 | goto nla_put_failure; | |
822 | n++; | |
823 | val = max(val / 1000, 1U); | |
824 | } | |
825 | if (i == TCP_METRIC_RTTVAR) { | |
826 | if (nla_put_u32(msg, TCP_METRIC_RTTVAR_US + 1, | |
827 | val) < 0) | |
828 | goto nla_put_failure; | |
829 | n++; | |
830 | val = max(val / 1000, 1U); | |
831 | } | |
832 | if (nla_put_u32(msg, i + 1, val) < 0) | |
d23ff701 JA |
833 | goto nla_put_failure; |
834 | n++; | |
835 | } | |
836 | if (n) | |
837 | nla_nest_end(msg, nest); | |
838 | else | |
839 | nla_nest_cancel(msg, nest); | |
840 | } | |
841 | ||
842 | { | |
843 | struct tcp_fastopen_metrics tfom_copy[1], *tfom; | |
844 | unsigned int seq; | |
845 | ||
846 | do { | |
847 | seq = read_seqbegin(&fastopen_seqlock); | |
848 | tfom_copy[0] = tm->tcpm_fastopen; | |
849 | } while (read_seqretry(&fastopen_seqlock, seq)); | |
850 | ||
851 | tfom = tfom_copy; | |
852 | if (tfom->mss && | |
853 | nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_MSS, | |
854 | tfom->mss) < 0) | |
855 | goto nla_put_failure; | |
856 | if (tfom->syn_loss && | |
857 | (nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_SYN_DROPS, | |
858 | tfom->syn_loss) < 0 || | |
859 | nla_put_msecs(msg, TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS, | |
860 | jiffies - tfom->last_syn_loss) < 0)) | |
861 | goto nla_put_failure; | |
862 | if (tfom->cookie.len > 0 && | |
863 | nla_put(msg, TCP_METRICS_ATTR_FOPEN_COOKIE, | |
864 | tfom->cookie.len, tfom->cookie.val) < 0) | |
865 | goto nla_put_failure; | |
866 | } | |
867 | ||
868 | return 0; | |
869 | ||
870 | nla_put_failure: | |
871 | return -EMSGSIZE; | |
872 | } | |
873 | ||
874 | static int tcp_metrics_dump_info(struct sk_buff *skb, | |
875 | struct netlink_callback *cb, | |
876 | struct tcp_metrics_block *tm) | |
877 | { | |
878 | void *hdr; | |
879 | ||
15e47304 | 880 | hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, |
d23ff701 JA |
881 | &tcp_metrics_nl_family, NLM_F_MULTI, |
882 | TCP_METRICS_CMD_GET); | |
883 | if (!hdr) | |
884 | return -EMSGSIZE; | |
885 | ||
886 | if (tcp_metrics_fill_info(skb, tm) < 0) | |
887 | goto nla_put_failure; | |
888 | ||
889 | return genlmsg_end(skb, hdr); | |
890 | ||
891 | nla_put_failure: | |
892 | genlmsg_cancel(skb, hdr); | |
893 | return -EMSGSIZE; | |
894 | } | |
895 | ||
896 | static int tcp_metrics_nl_dump(struct sk_buff *skb, | |
897 | struct netlink_callback *cb) | |
898 | { | |
899 | struct net *net = sock_net(skb->sk); | |
900 | unsigned int max_rows = 1U << net->ipv4.tcp_metrics_hash_log; | |
901 | unsigned int row, s_row = cb->args[0]; | |
902 | int s_col = cb->args[1], col = s_col; | |
903 | ||
904 | for (row = s_row; row < max_rows; row++, s_col = 0) { | |
905 | struct tcp_metrics_block *tm; | |
906 | struct tcpm_hash_bucket *hb = net->ipv4.tcp_metrics_hash + row; | |
907 | ||
908 | rcu_read_lock(); | |
909 | for (col = 0, tm = rcu_dereference(hb->chain); tm; | |
910 | tm = rcu_dereference(tm->tcpm_next), col++) { | |
911 | if (col < s_col) | |
912 | continue; | |
913 | if (tcp_metrics_dump_info(skb, cb, tm) < 0) { | |
914 | rcu_read_unlock(); | |
915 | goto done; | |
916 | } | |
917 | } | |
918 | rcu_read_unlock(); | |
919 | } | |
920 | ||
921 | done: | |
922 | cb->args[0] = row; | |
923 | cb->args[1] = col; | |
924 | return skb->len; | |
925 | } | |
926 | ||
3e7013dd CP |
927 | static int __parse_nl_addr(struct genl_info *info, struct inetpeer_addr *addr, |
928 | unsigned int *hash, int optional, int v4, int v6) | |
d23ff701 JA |
929 | { |
930 | struct nlattr *a; | |
931 | ||
3e7013dd | 932 | a = info->attrs[v4]; |
d23ff701 JA |
933 | if (a) { |
934 | addr->family = AF_INET; | |
935 | addr->addr.a4 = nla_get_be32(a); | |
3e7013dd CP |
936 | if (hash) |
937 | *hash = (__force unsigned int) addr->addr.a4; | |
d23ff701 JA |
938 | return 0; |
939 | } | |
3e7013dd | 940 | a = info->attrs[v6]; |
d23ff701 | 941 | if (a) { |
2c42a3fb | 942 | if (nla_len(a) != sizeof(struct in6_addr)) |
d23ff701 JA |
943 | return -EINVAL; |
944 | addr->family = AF_INET6; | |
945 | memcpy(addr->addr.a6, nla_data(a), sizeof(addr->addr.a6)); | |
3e7013dd CP |
946 | if (hash) |
947 | *hash = ipv6_addr_hash((struct in6_addr *) addr->addr.a6); | |
d23ff701 JA |
948 | return 0; |
949 | } | |
950 | return optional ? 1 : -EAFNOSUPPORT; | |
951 | } | |
952 | ||
3e7013dd CP |
953 | static int parse_nl_addr(struct genl_info *info, struct inetpeer_addr *addr, |
954 | unsigned int *hash, int optional) | |
955 | { | |
956 | return __parse_nl_addr(info, addr, hash, optional, | |
957 | TCP_METRICS_ATTR_ADDR_IPV4, | |
958 | TCP_METRICS_ATTR_ADDR_IPV6); | |
959 | } | |
960 | ||
961 | static int parse_nl_saddr(struct genl_info *info, struct inetpeer_addr *addr) | |
962 | { | |
963 | return __parse_nl_addr(info, addr, NULL, 0, | |
964 | TCP_METRICS_ATTR_SADDR_IPV4, | |
965 | TCP_METRICS_ATTR_SADDR_IPV6); | |
966 | } | |
967 | ||
d23ff701 JA |
968 | static int tcp_metrics_nl_cmd_get(struct sk_buff *skb, struct genl_info *info) |
969 | { | |
970 | struct tcp_metrics_block *tm; | |
3e7013dd | 971 | struct inetpeer_addr saddr, daddr; |
d23ff701 JA |
972 | unsigned int hash; |
973 | struct sk_buff *msg; | |
974 | struct net *net = genl_info_net(info); | |
975 | void *reply; | |
976 | int ret; | |
3e7013dd | 977 | bool src = true; |
d23ff701 | 978 | |
324fd55a | 979 | ret = parse_nl_addr(info, &daddr, &hash, 0); |
d23ff701 JA |
980 | if (ret < 0) |
981 | return ret; | |
982 | ||
3e7013dd CP |
983 | ret = parse_nl_saddr(info, &saddr); |
984 | if (ret < 0) | |
985 | src = false; | |
986 | ||
d23ff701 JA |
987 | msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
988 | if (!msg) | |
989 | return -ENOMEM; | |
990 | ||
991 | reply = genlmsg_put_reply(msg, info, &tcp_metrics_nl_family, 0, | |
992 | info->genlhdr->cmd); | |
993 | if (!reply) | |
994 | goto nla_put_failure; | |
995 | ||
996 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); | |
997 | ret = -ESRCH; | |
998 | rcu_read_lock(); | |
999 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; | |
1000 | tm = rcu_dereference(tm->tcpm_next)) { | |
3e7013dd CP |
1001 | if (addr_same(&tm->tcpm_daddr, &daddr) && |
1002 | (!src || addr_same(&tm->tcpm_saddr, &saddr))) { | |
d23ff701 JA |
1003 | ret = tcp_metrics_fill_info(msg, tm); |
1004 | break; | |
1005 | } | |
1006 | } | |
1007 | rcu_read_unlock(); | |
1008 | if (ret < 0) | |
1009 | goto out_free; | |
1010 | ||
1011 | genlmsg_end(msg, reply); | |
1012 | return genlmsg_reply(msg, info); | |
1013 | ||
1014 | nla_put_failure: | |
1015 | ret = -EMSGSIZE; | |
1016 | ||
1017 | out_free: | |
1018 | nlmsg_free(msg); | |
1019 | return ret; | |
1020 | } | |
1021 | ||
1022 | #define deref_locked_genl(p) \ | |
1023 | rcu_dereference_protected(p, lockdep_genl_is_held() && \ | |
1024 | lockdep_is_held(&tcp_metrics_lock)) | |
1025 | ||
1026 | #define deref_genl(p) rcu_dereference_protected(p, lockdep_genl_is_held()) | |
1027 | ||
1028 | static int tcp_metrics_flush_all(struct net *net) | |
1029 | { | |
1030 | unsigned int max_rows = 1U << net->ipv4.tcp_metrics_hash_log; | |
1031 | struct tcpm_hash_bucket *hb = net->ipv4.tcp_metrics_hash; | |
1032 | struct tcp_metrics_block *tm; | |
1033 | unsigned int row; | |
1034 | ||
1035 | for (row = 0; row < max_rows; row++, hb++) { | |
1036 | spin_lock_bh(&tcp_metrics_lock); | |
1037 | tm = deref_locked_genl(hb->chain); | |
1038 | if (tm) | |
1039 | hb->chain = NULL; | |
1040 | spin_unlock_bh(&tcp_metrics_lock); | |
1041 | while (tm) { | |
1042 | struct tcp_metrics_block *next; | |
1043 | ||
1044 | next = deref_genl(tm->tcpm_next); | |
1045 | kfree_rcu(tm, rcu_head); | |
1046 | tm = next; | |
1047 | } | |
1048 | } | |
1049 | return 0; | |
1050 | } | |
1051 | ||
1052 | static int tcp_metrics_nl_cmd_del(struct sk_buff *skb, struct genl_info *info) | |
1053 | { | |
1054 | struct tcpm_hash_bucket *hb; | |
00ca9c5b | 1055 | struct tcp_metrics_block *tm; |
d23ff701 | 1056 | struct tcp_metrics_block __rcu **pp; |
3e7013dd | 1057 | struct inetpeer_addr saddr, daddr; |
d23ff701 JA |
1058 | unsigned int hash; |
1059 | struct net *net = genl_info_net(info); | |
1060 | int ret; | |
00ca9c5b | 1061 | bool src = true, found = false; |
d23ff701 | 1062 | |
324fd55a | 1063 | ret = parse_nl_addr(info, &daddr, &hash, 1); |
d23ff701 JA |
1064 | if (ret < 0) |
1065 | return ret; | |
1066 | if (ret > 0) | |
1067 | return tcp_metrics_flush_all(net); | |
3e7013dd CP |
1068 | ret = parse_nl_saddr(info, &saddr); |
1069 | if (ret < 0) | |
1070 | src = false; | |
d23ff701 JA |
1071 | |
1072 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); | |
1073 | hb = net->ipv4.tcp_metrics_hash + hash; | |
1074 | pp = &hb->chain; | |
1075 | spin_lock_bh(&tcp_metrics_lock); | |
bbf852b9 | 1076 | for (tm = deref_locked_genl(*pp); tm; tm = deref_locked_genl(*pp)) { |
3e7013dd CP |
1077 | if (addr_same(&tm->tcpm_daddr, &daddr) && |
1078 | (!src || addr_same(&tm->tcpm_saddr, &saddr))) { | |
d23ff701 | 1079 | *pp = tm->tcpm_next; |
00ca9c5b CP |
1080 | kfree_rcu(tm, rcu_head); |
1081 | found = true; | |
bbf852b9 CP |
1082 | } else { |
1083 | pp = &tm->tcpm_next; | |
d23ff701 JA |
1084 | } |
1085 | } | |
1086 | spin_unlock_bh(&tcp_metrics_lock); | |
00ca9c5b | 1087 | if (!found) |
d23ff701 | 1088 | return -ESRCH; |
d23ff701 JA |
1089 | return 0; |
1090 | } | |
1091 | ||
4534de83 | 1092 | static const struct genl_ops tcp_metrics_nl_ops[] = { |
d23ff701 JA |
1093 | { |
1094 | .cmd = TCP_METRICS_CMD_GET, | |
1095 | .doit = tcp_metrics_nl_cmd_get, | |
1096 | .dumpit = tcp_metrics_nl_dump, | |
1097 | .policy = tcp_metrics_nl_policy, | |
d23ff701 JA |
1098 | }, |
1099 | { | |
1100 | .cmd = TCP_METRICS_CMD_DEL, | |
1101 | .doit = tcp_metrics_nl_cmd_del, | |
1102 | .policy = tcp_metrics_nl_policy, | |
1103 | .flags = GENL_ADMIN_PERM, | |
1104 | }, | |
1105 | }; | |
1106 | ||
5815d5e7 | 1107 | static unsigned int tcpmhash_entries; |
51c5d0c4 DM |
1108 | static int __init set_tcpmhash_entries(char *str) |
1109 | { | |
1110 | ssize_t ret; | |
1111 | ||
1112 | if (!str) | |
1113 | return 0; | |
1114 | ||
5815d5e7 | 1115 | ret = kstrtouint(str, 0, &tcpmhash_entries); |
51c5d0c4 DM |
1116 | if (ret) |
1117 | return 0; | |
1118 | ||
1119 | return 1; | |
1120 | } | |
1121 | __setup("tcpmhash_entries=", set_tcpmhash_entries); | |
1122 | ||
1123 | static int __net_init tcp_net_metrics_init(struct net *net) | |
1124 | { | |
5815d5e7 ED |
1125 | size_t size; |
1126 | unsigned int slots; | |
51c5d0c4 DM |
1127 | |
1128 | slots = tcpmhash_entries; | |
1129 | if (!slots) { | |
1130 | if (totalram_pages >= 128 * 1024) | |
1131 | slots = 16 * 1024; | |
1132 | else | |
1133 | slots = 8 * 1024; | |
1134 | } | |
1135 | ||
5815d5e7 ED |
1136 | net->ipv4.tcp_metrics_hash_log = order_base_2(slots); |
1137 | size = sizeof(struct tcpm_hash_bucket) << net->ipv4.tcp_metrics_hash_log; | |
51c5d0c4 | 1138 | |
976a702a ED |
1139 | net->ipv4.tcp_metrics_hash = kzalloc(size, GFP_KERNEL | __GFP_NOWARN); |
1140 | if (!net->ipv4.tcp_metrics_hash) | |
1141 | net->ipv4.tcp_metrics_hash = vzalloc(size); | |
1142 | ||
51c5d0c4 DM |
1143 | if (!net->ipv4.tcp_metrics_hash) |
1144 | return -ENOMEM; | |
1145 | ||
51c5d0c4 DM |
1146 | return 0; |
1147 | } | |
1148 | ||
1149 | static void __net_exit tcp_net_metrics_exit(struct net *net) | |
1150 | { | |
36471012 ED |
1151 | unsigned int i; |
1152 | ||
1153 | for (i = 0; i < (1U << net->ipv4.tcp_metrics_hash_log) ; i++) { | |
1154 | struct tcp_metrics_block *tm, *next; | |
1155 | ||
1156 | tm = rcu_dereference_protected(net->ipv4.tcp_metrics_hash[i].chain, 1); | |
1157 | while (tm) { | |
1158 | next = rcu_dereference_protected(tm->tcpm_next, 1); | |
1159 | kfree(tm); | |
1160 | tm = next; | |
1161 | } | |
1162 | } | |
4cb28970 | 1163 | kvfree(net->ipv4.tcp_metrics_hash); |
51c5d0c4 DM |
1164 | } |
1165 | ||
1166 | static __net_initdata struct pernet_operations tcp_net_metrics_ops = { | |
1167 | .init = tcp_net_metrics_init, | |
1168 | .exit = tcp_net_metrics_exit, | |
1169 | }; | |
1170 | ||
1171 | void __init tcp_metrics_init(void) | |
1172 | { | |
d23ff701 JA |
1173 | int ret; |
1174 | ||
1175 | ret = register_pernet_subsys(&tcp_net_metrics_ops); | |
1176 | if (ret < 0) | |
1177 | goto cleanup; | |
1178 | ret = genl_register_family_with_ops(&tcp_metrics_nl_family, | |
c53ed742 | 1179 | tcp_metrics_nl_ops); |
d23ff701 JA |
1180 | if (ret < 0) |
1181 | goto cleanup_subsys; | |
1182 | return; | |
1183 | ||
1184 | cleanup_subsys: | |
1185 | unregister_pernet_subsys(&tcp_net_metrics_ops); | |
1186 | ||
1187 | cleanup: | |
1188 | return; | |
51c5d0c4 | 1189 | } |