David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 1 | #include <linux/rcupdate.h> |
| 2 | #include <linux/spinlock.h> |
| 3 | #include <linux/jiffies.h> |
| 4 | #include <linux/bootmem.h> |
David S. Miller | ab92bb2 | 2012-07-09 16:19:30 -0700 | [diff] [blame] | 5 | #include <linux/module.h> |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 6 | #include <linux/cache.h> |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 7 | #include <linux/slab.h> |
| 8 | #include <linux/init.h> |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 9 | #include <linux/tcp.h> |
Eric Dumazet | 5815d5e | 2012-07-19 23:02:34 +0000 | [diff] [blame] | 10 | #include <linux/hash.h> |
Julian Anastasov | d23ff70 | 2012-09-04 11:03:15 +0000 | [diff] [blame] | 11 | #include <linux/tcp_metrics.h> |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 12 | |
| 13 | #include <net/inet_connection_sock.h> |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 14 | #include <net/net_namespace.h> |
David S. Miller | ab92bb2 | 2012-07-09 16:19:30 -0700 | [diff] [blame] | 15 | #include <net/request_sock.h> |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 16 | #include <net/inetpeer.h> |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 17 | #include <net/sock.h> |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 18 | #include <net/ipv6.h> |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 19 | #include <net/dst.h> |
| 20 | #include <net/tcp.h> |
Julian Anastasov | d23ff70 | 2012-09-04 11:03:15 +0000 | [diff] [blame] | 21 | #include <net/genetlink.h> |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 22 | |
| 23 | int sysctl_tcp_nometrics_save __read_mostly; |
| 24 | |
Yuchung Cheng | 1fe4c48 | 2012-07-19 06:43:06 +0000 | [diff] [blame] | 25 | struct tcp_fastopen_metrics { |
| 26 | u16 mss; |
Yuchung Cheng | aab4874 | 2012-07-19 06:43:10 +0000 | [diff] [blame] | 27 | u16 syn_loss:10; /* Recurring Fast Open SYN losses */ |
| 28 | unsigned long last_syn_loss; /* Last Fast Open SYN loss */ |
Yuchung Cheng | 1fe4c48 | 2012-07-19 06:43:06 +0000 | [diff] [blame] | 29 | struct tcp_fastopen_cookie cookie; |
| 30 | }; |
| 31 | |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 32 | struct tcp_metrics_block { |
| 33 | struct tcp_metrics_block __rcu *tcpm_next; |
| 34 | struct inetpeer_addr tcpm_addr; |
| 35 | unsigned long tcpm_stamp; |
David S. Miller | 81166dd | 2012-07-10 03:14:24 -0700 | [diff] [blame] | 36 | u32 tcpm_ts; |
| 37 | u32 tcpm_ts_stamp; |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 38 | u32 tcpm_lock; |
Julian Anastasov | d23ff70 | 2012-09-04 11:03:15 +0000 | [diff] [blame] | 39 | u32 tcpm_vals[TCP_METRIC_MAX + 1]; |
Yuchung Cheng | 1fe4c48 | 2012-07-19 06:43:06 +0000 | [diff] [blame] | 40 | struct tcp_fastopen_metrics tcpm_fastopen; |
Julian Anastasov | d23ff70 | 2012-09-04 11:03:15 +0000 | [diff] [blame] | 41 | |
| 42 | struct rcu_head rcu_head; |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 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 | |
| 99 | static void tcpm_suck_dst(struct tcp_metrics_block *tm, struct dst_entry *dst) |
| 100 | { |
| 101 | u32 val; |
| 102 | |
Julian Anastasov | 9a0a950 | 2012-07-23 10:46:38 +0300 | [diff] [blame] | 103 | tm->tcpm_stamp = jiffies; |
| 104 | |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 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 | |
| 118 | tm->tcpm_vals[TCP_METRIC_RTT] = dst_metric_raw(dst, RTAX_RTT); |
| 119 | tm->tcpm_vals[TCP_METRIC_RTTVAR] = dst_metric_raw(dst, RTAX_RTTVAR); |
| 120 | tm->tcpm_vals[TCP_METRIC_SSTHRESH] = dst_metric_raw(dst, RTAX_SSTHRESH); |
| 121 | tm->tcpm_vals[TCP_METRIC_CWND] = dst_metric_raw(dst, RTAX_CWND); |
| 122 | tm->tcpm_vals[TCP_METRIC_REORDERING] = dst_metric_raw(dst, RTAX_REORDERING); |
David S. Miller | 81166dd | 2012-07-10 03:14:24 -0700 | [diff] [blame] | 123 | tm->tcpm_ts = 0; |
| 124 | tm->tcpm_ts_stamp = 0; |
Yuchung Cheng | 1fe4c48 | 2012-07-19 06:43:06 +0000 | [diff] [blame] | 125 | tm->tcpm_fastopen.mss = 0; |
Yuchung Cheng | aab4874 | 2012-07-19 06:43:10 +0000 | [diff] [blame] | 126 | tm->tcpm_fastopen.syn_loss = 0; |
Yuchung Cheng | 1fe4c48 | 2012-07-19 06:43:06 +0000 | [diff] [blame] | 127 | tm->tcpm_fastopen.cookie.len = 0; |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 128 | } |
| 129 | |
| 130 | static struct tcp_metrics_block *tcpm_new(struct dst_entry *dst, |
| 131 | struct inetpeer_addr *addr, |
| 132 | unsigned int hash, |
| 133 | bool reclaim) |
| 134 | { |
| 135 | struct tcp_metrics_block *tm; |
| 136 | struct net *net; |
| 137 | |
| 138 | spin_lock_bh(&tcp_metrics_lock); |
| 139 | net = dev_net(dst->dev); |
| 140 | if (unlikely(reclaim)) { |
| 141 | struct tcp_metrics_block *oldest; |
| 142 | |
| 143 | oldest = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); |
| 144 | for (tm = rcu_dereference(oldest->tcpm_next); tm; |
| 145 | tm = rcu_dereference(tm->tcpm_next)) { |
| 146 | if (time_before(tm->tcpm_stamp, oldest->tcpm_stamp)) |
| 147 | oldest = tm; |
| 148 | } |
| 149 | tm = oldest; |
| 150 | } else { |
| 151 | tm = kmalloc(sizeof(*tm), GFP_ATOMIC); |
| 152 | if (!tm) |
| 153 | goto out_unlock; |
| 154 | } |
| 155 | tm->tcpm_addr = *addr; |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 156 | |
| 157 | tcpm_suck_dst(tm, dst); |
| 158 | |
| 159 | if (likely(!reclaim)) { |
| 160 | tm->tcpm_next = net->ipv4.tcp_metrics_hash[hash].chain; |
| 161 | rcu_assign_pointer(net->ipv4.tcp_metrics_hash[hash].chain, tm); |
| 162 | } |
| 163 | |
| 164 | out_unlock: |
| 165 | spin_unlock_bh(&tcp_metrics_lock); |
| 166 | return tm; |
| 167 | } |
| 168 | |
| 169 | #define TCP_METRICS_TIMEOUT (60 * 60 * HZ) |
| 170 | |
| 171 | static void tcpm_check_stamp(struct tcp_metrics_block *tm, struct dst_entry *dst) |
| 172 | { |
| 173 | if (tm && unlikely(time_after(jiffies, tm->tcpm_stamp + TCP_METRICS_TIMEOUT))) |
| 174 | tcpm_suck_dst(tm, dst); |
| 175 | } |
| 176 | |
| 177 | #define TCP_METRICS_RECLAIM_DEPTH 5 |
| 178 | #define TCP_METRICS_RECLAIM_PTR (struct tcp_metrics_block *) 0x1UL |
| 179 | |
| 180 | static struct tcp_metrics_block *tcp_get_encode(struct tcp_metrics_block *tm, int depth) |
| 181 | { |
| 182 | if (tm) |
| 183 | return tm; |
| 184 | if (depth > TCP_METRICS_RECLAIM_DEPTH) |
| 185 | return TCP_METRICS_RECLAIM_PTR; |
| 186 | return NULL; |
| 187 | } |
| 188 | |
| 189 | static struct tcp_metrics_block *__tcp_get_metrics(const struct inetpeer_addr *addr, |
| 190 | struct net *net, unsigned int hash) |
| 191 | { |
| 192 | struct tcp_metrics_block *tm; |
| 193 | int depth = 0; |
| 194 | |
| 195 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; |
| 196 | tm = rcu_dereference(tm->tcpm_next)) { |
| 197 | if (addr_same(&tm->tcpm_addr, addr)) |
| 198 | break; |
| 199 | depth++; |
| 200 | } |
| 201 | return tcp_get_encode(tm, depth); |
| 202 | } |
| 203 | |
| 204 | static struct tcp_metrics_block *__tcp_get_metrics_req(struct request_sock *req, |
| 205 | struct dst_entry *dst) |
| 206 | { |
| 207 | struct tcp_metrics_block *tm; |
| 208 | struct inetpeer_addr addr; |
| 209 | unsigned int hash; |
| 210 | struct net *net; |
| 211 | |
| 212 | addr.family = req->rsk_ops->family; |
| 213 | switch (addr.family) { |
| 214 | case AF_INET: |
| 215 | addr.addr.a4 = inet_rsk(req)->rmt_addr; |
| 216 | hash = (__force unsigned int) addr.addr.a4; |
| 217 | break; |
| 218 | case AF_INET6: |
| 219 | *(struct in6_addr *)addr.addr.a6 = inet6_rsk(req)->rmt_addr; |
Eric Dumazet | ddbe503 | 2012-07-18 08:11:12 +0000 | [diff] [blame] | 220 | hash = ipv6_addr_hash(&inet6_rsk(req)->rmt_addr); |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 221 | break; |
| 222 | default: |
| 223 | return NULL; |
| 224 | } |
| 225 | |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 226 | net = dev_net(dst->dev); |
Eric Dumazet | 5815d5e | 2012-07-19 23:02:34 +0000 | [diff] [blame] | 227 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 228 | |
| 229 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; |
| 230 | tm = rcu_dereference(tm->tcpm_next)) { |
| 231 | if (addr_same(&tm->tcpm_addr, &addr)) |
| 232 | break; |
| 233 | } |
| 234 | tcpm_check_stamp(tm, dst); |
| 235 | return tm; |
| 236 | } |
| 237 | |
David S. Miller | 81166dd | 2012-07-10 03:14:24 -0700 | [diff] [blame] | 238 | static struct tcp_metrics_block *__tcp_get_metrics_tw(struct inet_timewait_sock *tw) |
| 239 | { |
| 240 | struct inet6_timewait_sock *tw6; |
| 241 | struct tcp_metrics_block *tm; |
| 242 | struct inetpeer_addr addr; |
| 243 | unsigned int hash; |
| 244 | struct net *net; |
| 245 | |
| 246 | addr.family = tw->tw_family; |
| 247 | switch (addr.family) { |
| 248 | case AF_INET: |
| 249 | addr.addr.a4 = tw->tw_daddr; |
| 250 | hash = (__force unsigned int) addr.addr.a4; |
| 251 | break; |
| 252 | case AF_INET6: |
| 253 | tw6 = inet6_twsk((struct sock *)tw); |
| 254 | *(struct in6_addr *)addr.addr.a6 = tw6->tw_v6_daddr; |
Eric Dumazet | ddbe503 | 2012-07-18 08:11:12 +0000 | [diff] [blame] | 255 | hash = ipv6_addr_hash(&tw6->tw_v6_daddr); |
David S. Miller | 81166dd | 2012-07-10 03:14:24 -0700 | [diff] [blame] | 256 | break; |
| 257 | default: |
| 258 | return NULL; |
| 259 | } |
| 260 | |
David S. Miller | 81166dd | 2012-07-10 03:14:24 -0700 | [diff] [blame] | 261 | net = twsk_net(tw); |
Eric Dumazet | 5815d5e | 2012-07-19 23:02:34 +0000 | [diff] [blame] | 262 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
David S. Miller | 81166dd | 2012-07-10 03:14:24 -0700 | [diff] [blame] | 263 | |
| 264 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; |
| 265 | tm = rcu_dereference(tm->tcpm_next)) { |
| 266 | if (addr_same(&tm->tcpm_addr, &addr)) |
| 267 | break; |
| 268 | } |
| 269 | return tm; |
| 270 | } |
| 271 | |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 272 | static struct tcp_metrics_block *tcp_get_metrics(struct sock *sk, |
| 273 | struct dst_entry *dst, |
| 274 | bool create) |
| 275 | { |
| 276 | struct tcp_metrics_block *tm; |
| 277 | struct inetpeer_addr addr; |
| 278 | unsigned int hash; |
| 279 | struct net *net; |
| 280 | bool reclaim; |
| 281 | |
| 282 | addr.family = sk->sk_family; |
| 283 | switch (addr.family) { |
| 284 | case AF_INET: |
| 285 | addr.addr.a4 = inet_sk(sk)->inet_daddr; |
| 286 | hash = (__force unsigned int) addr.addr.a4; |
| 287 | break; |
| 288 | case AF_INET6: |
| 289 | *(struct in6_addr *)addr.addr.a6 = inet6_sk(sk)->daddr; |
Eric Dumazet | ddbe503 | 2012-07-18 08:11:12 +0000 | [diff] [blame] | 290 | hash = ipv6_addr_hash(&inet6_sk(sk)->daddr); |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 291 | break; |
| 292 | default: |
| 293 | return NULL; |
| 294 | } |
| 295 | |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 296 | net = dev_net(dst->dev); |
Eric Dumazet | 5815d5e | 2012-07-19 23:02:34 +0000 | [diff] [blame] | 297 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 298 | |
| 299 | tm = __tcp_get_metrics(&addr, net, hash); |
| 300 | reclaim = false; |
| 301 | if (tm == TCP_METRICS_RECLAIM_PTR) { |
| 302 | reclaim = true; |
| 303 | tm = NULL; |
| 304 | } |
| 305 | if (!tm && create) |
| 306 | tm = tcpm_new(dst, &addr, hash, reclaim); |
| 307 | else |
| 308 | tcpm_check_stamp(tm, dst); |
| 309 | |
| 310 | return tm; |
| 311 | } |
| 312 | |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 313 | /* Save metrics learned by this TCP session. This function is called |
| 314 | * only, when TCP finishes successfully i.e. when it enters TIME-WAIT |
| 315 | * or goes from LAST-ACK to CLOSE. |
| 316 | */ |
| 317 | void tcp_update_metrics(struct sock *sk) |
| 318 | { |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 319 | const struct inet_connection_sock *icsk = inet_csk(sk); |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 320 | struct dst_entry *dst = __sk_dst_get(sk); |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 321 | struct tcp_sock *tp = tcp_sk(sk); |
| 322 | struct tcp_metrics_block *tm; |
| 323 | unsigned long rtt; |
| 324 | u32 val; |
| 325 | int m; |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 326 | |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 327 | if (sysctl_tcp_nometrics_save || !dst) |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 328 | return; |
| 329 | |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 330 | if (dst->flags & DST_HOST) |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 331 | dst_confirm(dst); |
| 332 | |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 333 | rcu_read_lock(); |
| 334 | if (icsk->icsk_backoff || !tp->srtt) { |
| 335 | /* This session failed to estimate rtt. Why? |
| 336 | * Probably, no packets returned in time. Reset our |
| 337 | * results. |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 338 | */ |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 339 | tm = tcp_get_metrics(sk, dst, false); |
| 340 | if (tm && !tcp_metric_locked(tm, TCP_METRIC_RTT)) |
| 341 | tcp_metric_set(tm, TCP_METRIC_RTT, 0); |
| 342 | goto out_unlock; |
| 343 | } else |
| 344 | tm = tcp_get_metrics(sk, dst, true); |
| 345 | |
| 346 | if (!tm) |
| 347 | goto out_unlock; |
| 348 | |
| 349 | rtt = tcp_metric_get_jiffies(tm, TCP_METRIC_RTT); |
| 350 | m = rtt - tp->srtt; |
| 351 | |
| 352 | /* If newly calculated rtt larger than stored one, store new |
| 353 | * one. Otherwise, use EWMA. Remember, rtt overestimation is |
| 354 | * always better than underestimation. |
| 355 | */ |
| 356 | if (!tcp_metric_locked(tm, TCP_METRIC_RTT)) { |
| 357 | if (m <= 0) |
| 358 | rtt = tp->srtt; |
| 359 | else |
| 360 | rtt -= (m >> 3); |
| 361 | tcp_metric_set_msecs(tm, TCP_METRIC_RTT, rtt); |
| 362 | } |
| 363 | |
| 364 | if (!tcp_metric_locked(tm, TCP_METRIC_RTTVAR)) { |
| 365 | unsigned long var; |
| 366 | |
| 367 | if (m < 0) |
| 368 | m = -m; |
| 369 | |
| 370 | /* Scale deviation to rttvar fixed point */ |
| 371 | m >>= 1; |
| 372 | if (m < tp->mdev) |
| 373 | m = tp->mdev; |
| 374 | |
| 375 | var = tcp_metric_get_jiffies(tm, TCP_METRIC_RTTVAR); |
| 376 | if (m >= var) |
| 377 | var = m; |
| 378 | else |
| 379 | var -= (var - m) >> 2; |
| 380 | |
| 381 | tcp_metric_set_msecs(tm, TCP_METRIC_RTTVAR, var); |
| 382 | } |
| 383 | |
| 384 | if (tcp_in_initial_slowstart(tp)) { |
| 385 | /* Slow start still did not finish. */ |
| 386 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) { |
| 387 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); |
| 388 | if (val && (tp->snd_cwnd >> 1) > val) |
| 389 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, |
| 390 | tp->snd_cwnd >> 1); |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 391 | } |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 392 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { |
| 393 | val = tcp_metric_get(tm, TCP_METRIC_CWND); |
| 394 | if (tp->snd_cwnd > val) |
| 395 | tcp_metric_set(tm, TCP_METRIC_CWND, |
| 396 | tp->snd_cwnd); |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 397 | } |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 398 | } else if (tp->snd_cwnd > tp->snd_ssthresh && |
| 399 | icsk->icsk_ca_state == TCP_CA_Open) { |
| 400 | /* Cong. avoidance phase, cwnd is reliable. */ |
| 401 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) |
| 402 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, |
| 403 | max(tp->snd_cwnd >> 1, tp->snd_ssthresh)); |
| 404 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { |
| 405 | val = tcp_metric_get(tm, TCP_METRIC_CWND); |
Alexander Duyck | 2100844 | 2012-07-11 17:18:04 -0700 | [diff] [blame] | 406 | tcp_metric_set(tm, TCP_METRIC_CWND, (val + tp->snd_cwnd) >> 1); |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 407 | } |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 408 | } else { |
| 409 | /* Else slow start did not finish, cwnd is non-sense, |
| 410 | * ssthresh may be also invalid. |
| 411 | */ |
| 412 | if (!tcp_metric_locked(tm, TCP_METRIC_CWND)) { |
| 413 | val = tcp_metric_get(tm, TCP_METRIC_CWND); |
| 414 | tcp_metric_set(tm, TCP_METRIC_CWND, |
| 415 | (val + tp->snd_ssthresh) >> 1); |
| 416 | } |
| 417 | if (!tcp_metric_locked(tm, TCP_METRIC_SSTHRESH)) { |
| 418 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); |
| 419 | if (val && tp->snd_ssthresh > val) |
| 420 | tcp_metric_set(tm, TCP_METRIC_SSTHRESH, |
| 421 | tp->snd_ssthresh); |
| 422 | } |
| 423 | if (!tcp_metric_locked(tm, TCP_METRIC_REORDERING)) { |
| 424 | val = tcp_metric_get(tm, TCP_METRIC_REORDERING); |
| 425 | if (val < tp->reordering && |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 426 | tp->reordering != sysctl_tcp_reordering) |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 427 | tcp_metric_set(tm, TCP_METRIC_REORDERING, |
| 428 | tp->reordering); |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 429 | } |
| 430 | } |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 431 | tm->tcpm_stamp = jiffies; |
| 432 | out_unlock: |
| 433 | rcu_read_unlock(); |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 434 | } |
| 435 | |
| 436 | /* Initialize metrics on socket. */ |
| 437 | |
| 438 | void tcp_init_metrics(struct sock *sk) |
| 439 | { |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 440 | struct dst_entry *dst = __sk_dst_get(sk); |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 441 | struct tcp_sock *tp = tcp_sk(sk); |
| 442 | struct tcp_metrics_block *tm; |
| 443 | u32 val; |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 444 | |
| 445 | if (dst == NULL) |
| 446 | goto reset; |
| 447 | |
| 448 | dst_confirm(dst); |
| 449 | |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 450 | rcu_read_lock(); |
| 451 | tm = tcp_get_metrics(sk, dst, true); |
| 452 | if (!tm) { |
| 453 | rcu_read_unlock(); |
| 454 | goto reset; |
| 455 | } |
| 456 | |
| 457 | if (tcp_metric_locked(tm, TCP_METRIC_CWND)) |
| 458 | tp->snd_cwnd_clamp = tcp_metric_get(tm, TCP_METRIC_CWND); |
| 459 | |
| 460 | val = tcp_metric_get(tm, TCP_METRIC_SSTHRESH); |
| 461 | if (val) { |
| 462 | tp->snd_ssthresh = val; |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 463 | if (tp->snd_ssthresh > tp->snd_cwnd_clamp) |
| 464 | tp->snd_ssthresh = tp->snd_cwnd_clamp; |
| 465 | } else { |
| 466 | /* ssthresh may have been reduced unnecessarily during. |
| 467 | * 3WHS. Restore it back to its initial default. |
| 468 | */ |
| 469 | tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; |
| 470 | } |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 471 | val = tcp_metric_get(tm, TCP_METRIC_REORDERING); |
| 472 | if (val && tp->reordering != val) { |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 473 | tcp_disable_fack(tp); |
| 474 | tcp_disable_early_retrans(tp); |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 475 | tp->reordering = val; |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 476 | } |
| 477 | |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 478 | val = tcp_metric_get(tm, TCP_METRIC_RTT); |
| 479 | if (val == 0 || tp->srtt == 0) { |
| 480 | rcu_read_unlock(); |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 481 | goto reset; |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 482 | } |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 483 | /* Initial rtt is determined from SYN,SYN-ACK. |
| 484 | * The segment is small and rtt may appear much |
| 485 | * less than real one. Use per-dst memory |
| 486 | * to make it more realistic. |
| 487 | * |
| 488 | * A bit of theory. RTT is time passed after "normal" sized packet |
| 489 | * is sent until it is ACKed. In normal circumstances sending small |
| 490 | * packets force peer to delay ACKs and calculation is correct too. |
| 491 | * The algorithm is adaptive and, provided we follow specs, it |
| 492 | * NEVER underestimate RTT. BUT! If peer tries to make some clever |
| 493 | * tricks sort of "quick acks" for time long enough to decrease RTT |
| 494 | * to low value, and then abruptly stops to do it and starts to delay |
| 495 | * ACKs, wait for troubles. |
| 496 | */ |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 497 | val = msecs_to_jiffies(val); |
| 498 | if (val > tp->srtt) { |
| 499 | tp->srtt = val; |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 500 | tp->rtt_seq = tp->snd_nxt; |
| 501 | } |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 502 | val = tcp_metric_get_jiffies(tm, TCP_METRIC_RTTVAR); |
| 503 | if (val > tp->mdev) { |
| 504 | tp->mdev = val; |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 505 | tp->mdev_max = tp->rttvar = max(tp->mdev, tcp_rto_min(sk)); |
| 506 | } |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 507 | rcu_read_unlock(); |
| 508 | |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 509 | tcp_set_rto(sk); |
| 510 | reset: |
| 511 | if (tp->srtt == 0) { |
| 512 | /* RFC6298: 5.7 We've failed to get a valid RTT sample from |
| 513 | * 3WHS. This is most likely due to retransmission, |
| 514 | * including spurious one. Reset the RTO back to 3secs |
| 515 | * from the more aggressive 1sec to avoid more spurious |
| 516 | * retransmission. |
| 517 | */ |
| 518 | tp->mdev = tp->mdev_max = tp->rttvar = TCP_TIMEOUT_FALLBACK; |
| 519 | inet_csk(sk)->icsk_rto = TCP_TIMEOUT_FALLBACK; |
| 520 | } |
| 521 | /* Cut cwnd down to 1 per RFC5681 if SYN or SYN-ACK has been |
| 522 | * retransmitted. In light of RFC6298 more aggressive 1sec |
| 523 | * initRTO, we only reset cwnd when more than 1 SYN/SYN-ACK |
| 524 | * retransmission has occurred. |
| 525 | */ |
| 526 | if (tp->total_retrans > 1) |
| 527 | tp->snd_cwnd = 1; |
| 528 | else |
| 529 | tp->snd_cwnd = tcp_init_cwnd(tp, dst); |
| 530 | tp->snd_cwnd_stamp = tcp_time_stamp; |
| 531 | } |
David S. Miller | ab92bb2 | 2012-07-09 16:19:30 -0700 | [diff] [blame] | 532 | |
David S. Miller | 81166dd | 2012-07-10 03:14:24 -0700 | [diff] [blame] | 533 | bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst, bool paws_check) |
David S. Miller | ab92bb2 | 2012-07-09 16:19:30 -0700 | [diff] [blame] | 534 | { |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 535 | struct tcp_metrics_block *tm; |
| 536 | bool ret; |
| 537 | |
David S. Miller | ab92bb2 | 2012-07-09 16:19:30 -0700 | [diff] [blame] | 538 | if (!dst) |
| 539 | return false; |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 540 | |
| 541 | rcu_read_lock(); |
| 542 | tm = __tcp_get_metrics_req(req, dst); |
David S. Miller | 81166dd | 2012-07-10 03:14:24 -0700 | [diff] [blame] | 543 | if (paws_check) { |
| 544 | if (tm && |
| 545 | (u32)get_seconds() - tm->tcpm_ts_stamp < TCP_PAWS_MSL && |
| 546 | (s32)(tm->tcpm_ts - req->ts_recent) > TCP_PAWS_WINDOW) |
| 547 | ret = false; |
| 548 | else |
| 549 | ret = true; |
| 550 | } else { |
| 551 | if (tm && tcp_metric_get(tm, TCP_METRIC_RTT) && tm->tcpm_ts_stamp) |
| 552 | ret = true; |
| 553 | else |
| 554 | ret = false; |
| 555 | } |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 556 | rcu_read_unlock(); |
| 557 | |
| 558 | return ret; |
David S. Miller | ab92bb2 | 2012-07-09 16:19:30 -0700 | [diff] [blame] | 559 | } |
| 560 | EXPORT_SYMBOL_GPL(tcp_peer_is_proven); |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 561 | |
David S. Miller | 81166dd | 2012-07-10 03:14:24 -0700 | [diff] [blame] | 562 | void tcp_fetch_timewait_stamp(struct sock *sk, struct dst_entry *dst) |
| 563 | { |
| 564 | struct tcp_metrics_block *tm; |
| 565 | |
| 566 | rcu_read_lock(); |
| 567 | tm = tcp_get_metrics(sk, dst, true); |
| 568 | if (tm) { |
| 569 | struct tcp_sock *tp = tcp_sk(sk); |
| 570 | |
| 571 | if ((u32)get_seconds() - tm->tcpm_ts_stamp <= TCP_PAWS_MSL) { |
| 572 | tp->rx_opt.ts_recent_stamp = tm->tcpm_ts_stamp; |
| 573 | tp->rx_opt.ts_recent = tm->tcpm_ts; |
| 574 | } |
| 575 | } |
| 576 | rcu_read_unlock(); |
| 577 | } |
| 578 | EXPORT_SYMBOL_GPL(tcp_fetch_timewait_stamp); |
| 579 | |
| 580 | /* VJ's idea. Save last timestamp seen from this destination and hold |
| 581 | * it at least for normal timewait interval to use for duplicate |
| 582 | * segment detection in subsequent connections, before they enter |
| 583 | * synchronized state. |
| 584 | */ |
| 585 | bool tcp_remember_stamp(struct sock *sk) |
| 586 | { |
| 587 | struct dst_entry *dst = __sk_dst_get(sk); |
| 588 | bool ret = false; |
| 589 | |
| 590 | if (dst) { |
| 591 | struct tcp_metrics_block *tm; |
| 592 | |
| 593 | rcu_read_lock(); |
| 594 | tm = tcp_get_metrics(sk, dst, true); |
| 595 | if (tm) { |
| 596 | struct tcp_sock *tp = tcp_sk(sk); |
| 597 | |
| 598 | if ((s32)(tm->tcpm_ts - tp->rx_opt.ts_recent) <= 0 || |
| 599 | ((u32)get_seconds() - tm->tcpm_ts_stamp > TCP_PAWS_MSL && |
| 600 | tm->tcpm_ts_stamp <= (u32)tp->rx_opt.ts_recent_stamp)) { |
| 601 | tm->tcpm_ts_stamp = (u32)tp->rx_opt.ts_recent_stamp; |
| 602 | tm->tcpm_ts = tp->rx_opt.ts_recent; |
| 603 | } |
| 604 | ret = true; |
| 605 | } |
| 606 | rcu_read_unlock(); |
| 607 | } |
| 608 | return ret; |
| 609 | } |
| 610 | |
| 611 | bool tcp_tw_remember_stamp(struct inet_timewait_sock *tw) |
| 612 | { |
| 613 | struct tcp_metrics_block *tm; |
| 614 | bool ret = false; |
| 615 | |
| 616 | rcu_read_lock(); |
| 617 | tm = __tcp_get_metrics_tw(tw); |
Julian Anastasov | 9a0a950 | 2012-07-23 10:46:38 +0300 | [diff] [blame] | 618 | if (tm) { |
David S. Miller | 81166dd | 2012-07-10 03:14:24 -0700 | [diff] [blame] | 619 | const struct tcp_timewait_sock *tcptw; |
| 620 | struct sock *sk = (struct sock *) tw; |
| 621 | |
| 622 | tcptw = tcp_twsk(sk); |
| 623 | if ((s32)(tm->tcpm_ts - tcptw->tw_ts_recent) <= 0 || |
| 624 | ((u32)get_seconds() - tm->tcpm_ts_stamp > TCP_PAWS_MSL && |
| 625 | tm->tcpm_ts_stamp <= (u32)tcptw->tw_ts_recent_stamp)) { |
| 626 | tm->tcpm_ts_stamp = (u32)tcptw->tw_ts_recent_stamp; |
| 627 | tm->tcpm_ts = tcptw->tw_ts_recent; |
| 628 | } |
| 629 | ret = true; |
| 630 | } |
| 631 | rcu_read_unlock(); |
| 632 | |
| 633 | return ret; |
| 634 | } |
| 635 | |
Yuchung Cheng | 1fe4c48 | 2012-07-19 06:43:06 +0000 | [diff] [blame] | 636 | static DEFINE_SEQLOCK(fastopen_seqlock); |
| 637 | |
| 638 | void tcp_fastopen_cache_get(struct sock *sk, u16 *mss, |
Yuchung Cheng | aab4874 | 2012-07-19 06:43:10 +0000 | [diff] [blame] | 639 | struct tcp_fastopen_cookie *cookie, |
| 640 | int *syn_loss, unsigned long *last_syn_loss) |
Yuchung Cheng | 1fe4c48 | 2012-07-19 06:43:06 +0000 | [diff] [blame] | 641 | { |
| 642 | struct tcp_metrics_block *tm; |
| 643 | |
| 644 | rcu_read_lock(); |
| 645 | tm = tcp_get_metrics(sk, __sk_dst_get(sk), false); |
| 646 | if (tm) { |
| 647 | struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; |
| 648 | unsigned int seq; |
| 649 | |
| 650 | do { |
| 651 | seq = read_seqbegin(&fastopen_seqlock); |
| 652 | if (tfom->mss) |
| 653 | *mss = tfom->mss; |
| 654 | *cookie = tfom->cookie; |
Yuchung Cheng | aab4874 | 2012-07-19 06:43:10 +0000 | [diff] [blame] | 655 | *syn_loss = tfom->syn_loss; |
| 656 | *last_syn_loss = *syn_loss ? tfom->last_syn_loss : 0; |
Yuchung Cheng | 1fe4c48 | 2012-07-19 06:43:06 +0000 | [diff] [blame] | 657 | } while (read_seqretry(&fastopen_seqlock, seq)); |
| 658 | } |
| 659 | rcu_read_unlock(); |
| 660 | } |
| 661 | |
Yuchung Cheng | 1fe4c48 | 2012-07-19 06:43:06 +0000 | [diff] [blame] | 662 | void tcp_fastopen_cache_set(struct sock *sk, u16 mss, |
Yuchung Cheng | aab4874 | 2012-07-19 06:43:10 +0000 | [diff] [blame] | 663 | struct tcp_fastopen_cookie *cookie, bool syn_lost) |
Yuchung Cheng | 1fe4c48 | 2012-07-19 06:43:06 +0000 | [diff] [blame] | 664 | { |
| 665 | struct tcp_metrics_block *tm; |
| 666 | |
| 667 | rcu_read_lock(); |
| 668 | tm = tcp_get_metrics(sk, __sk_dst_get(sk), true); |
| 669 | if (tm) { |
| 670 | struct tcp_fastopen_metrics *tfom = &tm->tcpm_fastopen; |
| 671 | |
| 672 | write_seqlock_bh(&fastopen_seqlock); |
| 673 | tfom->mss = mss; |
| 674 | if (cookie->len > 0) |
| 675 | tfom->cookie = *cookie; |
Yuchung Cheng | aab4874 | 2012-07-19 06:43:10 +0000 | [diff] [blame] | 676 | if (syn_lost) { |
| 677 | ++tfom->syn_loss; |
| 678 | tfom->last_syn_loss = jiffies; |
| 679 | } else |
| 680 | tfom->syn_loss = 0; |
Yuchung Cheng | 1fe4c48 | 2012-07-19 06:43:06 +0000 | [diff] [blame] | 681 | write_sequnlock_bh(&fastopen_seqlock); |
| 682 | } |
| 683 | rcu_read_unlock(); |
| 684 | } |
| 685 | |
Julian Anastasov | d23ff70 | 2012-09-04 11:03:15 +0000 | [diff] [blame] | 686 | static struct genl_family tcp_metrics_nl_family = { |
| 687 | .id = GENL_ID_GENERATE, |
| 688 | .hdrsize = 0, |
| 689 | .name = TCP_METRICS_GENL_NAME, |
| 690 | .version = TCP_METRICS_GENL_VERSION, |
| 691 | .maxattr = TCP_METRICS_ATTR_MAX, |
| 692 | .netnsok = true, |
| 693 | }; |
| 694 | |
| 695 | static struct nla_policy tcp_metrics_nl_policy[TCP_METRICS_ATTR_MAX + 1] = { |
| 696 | [TCP_METRICS_ATTR_ADDR_IPV4] = { .type = NLA_U32, }, |
| 697 | [TCP_METRICS_ATTR_ADDR_IPV6] = { .type = NLA_BINARY, |
| 698 | .len = sizeof(struct in6_addr), }, |
| 699 | /* Following attributes are not received for GET/DEL, |
| 700 | * we keep them for reference |
| 701 | */ |
| 702 | #if 0 |
| 703 | [TCP_METRICS_ATTR_AGE] = { .type = NLA_MSECS, }, |
| 704 | [TCP_METRICS_ATTR_TW_TSVAL] = { .type = NLA_U32, }, |
| 705 | [TCP_METRICS_ATTR_TW_TS_STAMP] = { .type = NLA_S32, }, |
| 706 | [TCP_METRICS_ATTR_VALS] = { .type = NLA_NESTED, }, |
| 707 | [TCP_METRICS_ATTR_FOPEN_MSS] = { .type = NLA_U16, }, |
| 708 | [TCP_METRICS_ATTR_FOPEN_SYN_DROPS] = { .type = NLA_U16, }, |
| 709 | [TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS] = { .type = NLA_MSECS, }, |
| 710 | [TCP_METRICS_ATTR_FOPEN_COOKIE] = { .type = NLA_BINARY, |
| 711 | .len = TCP_FASTOPEN_COOKIE_MAX, }, |
| 712 | #endif |
| 713 | }; |
| 714 | |
| 715 | /* Add attributes, caller cancels its header on failure */ |
| 716 | static int tcp_metrics_fill_info(struct sk_buff *msg, |
| 717 | struct tcp_metrics_block *tm) |
| 718 | { |
| 719 | struct nlattr *nest; |
| 720 | int i; |
| 721 | |
| 722 | switch (tm->tcpm_addr.family) { |
| 723 | case AF_INET: |
| 724 | if (nla_put_be32(msg, TCP_METRICS_ATTR_ADDR_IPV4, |
| 725 | tm->tcpm_addr.addr.a4) < 0) |
| 726 | goto nla_put_failure; |
| 727 | break; |
| 728 | case AF_INET6: |
| 729 | if (nla_put(msg, TCP_METRICS_ATTR_ADDR_IPV6, 16, |
| 730 | tm->tcpm_addr.addr.a6) < 0) |
| 731 | goto nla_put_failure; |
| 732 | break; |
| 733 | default: |
| 734 | return -EAFNOSUPPORT; |
| 735 | } |
| 736 | |
| 737 | if (nla_put_msecs(msg, TCP_METRICS_ATTR_AGE, |
| 738 | jiffies - tm->tcpm_stamp) < 0) |
| 739 | goto nla_put_failure; |
| 740 | if (tm->tcpm_ts_stamp) { |
| 741 | if (nla_put_s32(msg, TCP_METRICS_ATTR_TW_TS_STAMP, |
| 742 | (s32) (get_seconds() - tm->tcpm_ts_stamp)) < 0) |
| 743 | goto nla_put_failure; |
| 744 | if (nla_put_u32(msg, TCP_METRICS_ATTR_TW_TSVAL, |
| 745 | tm->tcpm_ts) < 0) |
| 746 | goto nla_put_failure; |
| 747 | } |
| 748 | |
| 749 | { |
| 750 | int n = 0; |
| 751 | |
| 752 | nest = nla_nest_start(msg, TCP_METRICS_ATTR_VALS); |
| 753 | if (!nest) |
| 754 | goto nla_put_failure; |
| 755 | for (i = 0; i < TCP_METRIC_MAX + 1; i++) { |
| 756 | if (!tm->tcpm_vals[i]) |
| 757 | continue; |
| 758 | if (nla_put_u32(msg, i + 1, tm->tcpm_vals[i]) < 0) |
| 759 | goto nla_put_failure; |
| 760 | n++; |
| 761 | } |
| 762 | if (n) |
| 763 | nla_nest_end(msg, nest); |
| 764 | else |
| 765 | nla_nest_cancel(msg, nest); |
| 766 | } |
| 767 | |
| 768 | { |
| 769 | struct tcp_fastopen_metrics tfom_copy[1], *tfom; |
| 770 | unsigned int seq; |
| 771 | |
| 772 | do { |
| 773 | seq = read_seqbegin(&fastopen_seqlock); |
| 774 | tfom_copy[0] = tm->tcpm_fastopen; |
| 775 | } while (read_seqretry(&fastopen_seqlock, seq)); |
| 776 | |
| 777 | tfom = tfom_copy; |
| 778 | if (tfom->mss && |
| 779 | nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_MSS, |
| 780 | tfom->mss) < 0) |
| 781 | goto nla_put_failure; |
| 782 | if (tfom->syn_loss && |
| 783 | (nla_put_u16(msg, TCP_METRICS_ATTR_FOPEN_SYN_DROPS, |
| 784 | tfom->syn_loss) < 0 || |
| 785 | nla_put_msecs(msg, TCP_METRICS_ATTR_FOPEN_SYN_DROP_TS, |
| 786 | jiffies - tfom->last_syn_loss) < 0)) |
| 787 | goto nla_put_failure; |
| 788 | if (tfom->cookie.len > 0 && |
| 789 | nla_put(msg, TCP_METRICS_ATTR_FOPEN_COOKIE, |
| 790 | tfom->cookie.len, tfom->cookie.val) < 0) |
| 791 | goto nla_put_failure; |
| 792 | } |
| 793 | |
| 794 | return 0; |
| 795 | |
| 796 | nla_put_failure: |
| 797 | return -EMSGSIZE; |
| 798 | } |
| 799 | |
| 800 | static int tcp_metrics_dump_info(struct sk_buff *skb, |
| 801 | struct netlink_callback *cb, |
| 802 | struct tcp_metrics_block *tm) |
| 803 | { |
| 804 | void *hdr; |
| 805 | |
Eric W. Biederman | 15e4730 | 2012-09-07 20:12:54 +0000 | [diff] [blame] | 806 | hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, |
Julian Anastasov | d23ff70 | 2012-09-04 11:03:15 +0000 | [diff] [blame] | 807 | &tcp_metrics_nl_family, NLM_F_MULTI, |
| 808 | TCP_METRICS_CMD_GET); |
| 809 | if (!hdr) |
| 810 | return -EMSGSIZE; |
| 811 | |
| 812 | if (tcp_metrics_fill_info(skb, tm) < 0) |
| 813 | goto nla_put_failure; |
| 814 | |
| 815 | return genlmsg_end(skb, hdr); |
| 816 | |
| 817 | nla_put_failure: |
| 818 | genlmsg_cancel(skb, hdr); |
| 819 | return -EMSGSIZE; |
| 820 | } |
| 821 | |
| 822 | static int tcp_metrics_nl_dump(struct sk_buff *skb, |
| 823 | struct netlink_callback *cb) |
| 824 | { |
| 825 | struct net *net = sock_net(skb->sk); |
| 826 | unsigned int max_rows = 1U << net->ipv4.tcp_metrics_hash_log; |
| 827 | unsigned int row, s_row = cb->args[0]; |
| 828 | int s_col = cb->args[1], col = s_col; |
| 829 | |
| 830 | for (row = s_row; row < max_rows; row++, s_col = 0) { |
| 831 | struct tcp_metrics_block *tm; |
| 832 | struct tcpm_hash_bucket *hb = net->ipv4.tcp_metrics_hash + row; |
| 833 | |
| 834 | rcu_read_lock(); |
| 835 | for (col = 0, tm = rcu_dereference(hb->chain); tm; |
| 836 | tm = rcu_dereference(tm->tcpm_next), col++) { |
| 837 | if (col < s_col) |
| 838 | continue; |
| 839 | if (tcp_metrics_dump_info(skb, cb, tm) < 0) { |
| 840 | rcu_read_unlock(); |
| 841 | goto done; |
| 842 | } |
| 843 | } |
| 844 | rcu_read_unlock(); |
| 845 | } |
| 846 | |
| 847 | done: |
| 848 | cb->args[0] = row; |
| 849 | cb->args[1] = col; |
| 850 | return skb->len; |
| 851 | } |
| 852 | |
| 853 | static int parse_nl_addr(struct genl_info *info, struct inetpeer_addr *addr, |
| 854 | unsigned int *hash, int optional) |
| 855 | { |
| 856 | struct nlattr *a; |
| 857 | |
| 858 | a = info->attrs[TCP_METRICS_ATTR_ADDR_IPV4]; |
| 859 | if (a) { |
| 860 | addr->family = AF_INET; |
| 861 | addr->addr.a4 = nla_get_be32(a); |
| 862 | *hash = (__force unsigned int) addr->addr.a4; |
| 863 | return 0; |
| 864 | } |
| 865 | a = info->attrs[TCP_METRICS_ATTR_ADDR_IPV6]; |
| 866 | if (a) { |
Julian Anastasov | 2c42a3f | 2012-10-30 12:03:09 +0000 | [diff] [blame] | 867 | if (nla_len(a) != sizeof(struct in6_addr)) |
Julian Anastasov | d23ff70 | 2012-09-04 11:03:15 +0000 | [diff] [blame] | 868 | return -EINVAL; |
| 869 | addr->family = AF_INET6; |
| 870 | memcpy(addr->addr.a6, nla_data(a), sizeof(addr->addr.a6)); |
| 871 | *hash = ipv6_addr_hash((struct in6_addr *) addr->addr.a6); |
| 872 | return 0; |
| 873 | } |
| 874 | return optional ? 1 : -EAFNOSUPPORT; |
| 875 | } |
| 876 | |
| 877 | static int tcp_metrics_nl_cmd_get(struct sk_buff *skb, struct genl_info *info) |
| 878 | { |
| 879 | struct tcp_metrics_block *tm; |
| 880 | struct inetpeer_addr addr; |
| 881 | unsigned int hash; |
| 882 | struct sk_buff *msg; |
| 883 | struct net *net = genl_info_net(info); |
| 884 | void *reply; |
| 885 | int ret; |
| 886 | |
| 887 | ret = parse_nl_addr(info, &addr, &hash, 0); |
| 888 | if (ret < 0) |
| 889 | return ret; |
| 890 | |
| 891 | msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
| 892 | if (!msg) |
| 893 | return -ENOMEM; |
| 894 | |
| 895 | reply = genlmsg_put_reply(msg, info, &tcp_metrics_nl_family, 0, |
| 896 | info->genlhdr->cmd); |
| 897 | if (!reply) |
| 898 | goto nla_put_failure; |
| 899 | |
| 900 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
| 901 | ret = -ESRCH; |
| 902 | rcu_read_lock(); |
| 903 | for (tm = rcu_dereference(net->ipv4.tcp_metrics_hash[hash].chain); tm; |
| 904 | tm = rcu_dereference(tm->tcpm_next)) { |
| 905 | if (addr_same(&tm->tcpm_addr, &addr)) { |
| 906 | ret = tcp_metrics_fill_info(msg, tm); |
| 907 | break; |
| 908 | } |
| 909 | } |
| 910 | rcu_read_unlock(); |
| 911 | if (ret < 0) |
| 912 | goto out_free; |
| 913 | |
| 914 | genlmsg_end(msg, reply); |
| 915 | return genlmsg_reply(msg, info); |
| 916 | |
| 917 | nla_put_failure: |
| 918 | ret = -EMSGSIZE; |
| 919 | |
| 920 | out_free: |
| 921 | nlmsg_free(msg); |
| 922 | return ret; |
| 923 | } |
| 924 | |
| 925 | #define deref_locked_genl(p) \ |
| 926 | rcu_dereference_protected(p, lockdep_genl_is_held() && \ |
| 927 | lockdep_is_held(&tcp_metrics_lock)) |
| 928 | |
| 929 | #define deref_genl(p) rcu_dereference_protected(p, lockdep_genl_is_held()) |
| 930 | |
| 931 | static int tcp_metrics_flush_all(struct net *net) |
| 932 | { |
| 933 | unsigned int max_rows = 1U << net->ipv4.tcp_metrics_hash_log; |
| 934 | struct tcpm_hash_bucket *hb = net->ipv4.tcp_metrics_hash; |
| 935 | struct tcp_metrics_block *tm; |
| 936 | unsigned int row; |
| 937 | |
| 938 | for (row = 0; row < max_rows; row++, hb++) { |
| 939 | spin_lock_bh(&tcp_metrics_lock); |
| 940 | tm = deref_locked_genl(hb->chain); |
| 941 | if (tm) |
| 942 | hb->chain = NULL; |
| 943 | spin_unlock_bh(&tcp_metrics_lock); |
| 944 | while (tm) { |
| 945 | struct tcp_metrics_block *next; |
| 946 | |
| 947 | next = deref_genl(tm->tcpm_next); |
| 948 | kfree_rcu(tm, rcu_head); |
| 949 | tm = next; |
| 950 | } |
| 951 | } |
| 952 | return 0; |
| 953 | } |
| 954 | |
| 955 | static int tcp_metrics_nl_cmd_del(struct sk_buff *skb, struct genl_info *info) |
| 956 | { |
| 957 | struct tcpm_hash_bucket *hb; |
| 958 | struct tcp_metrics_block *tm; |
| 959 | struct tcp_metrics_block __rcu **pp; |
| 960 | struct inetpeer_addr addr; |
| 961 | unsigned int hash; |
| 962 | struct net *net = genl_info_net(info); |
| 963 | int ret; |
| 964 | |
| 965 | ret = parse_nl_addr(info, &addr, &hash, 1); |
| 966 | if (ret < 0) |
| 967 | return ret; |
| 968 | if (ret > 0) |
| 969 | return tcp_metrics_flush_all(net); |
| 970 | |
| 971 | hash = hash_32(hash, net->ipv4.tcp_metrics_hash_log); |
| 972 | hb = net->ipv4.tcp_metrics_hash + hash; |
| 973 | pp = &hb->chain; |
| 974 | spin_lock_bh(&tcp_metrics_lock); |
| 975 | for (tm = deref_locked_genl(*pp); tm; |
| 976 | pp = &tm->tcpm_next, tm = deref_locked_genl(*pp)) { |
| 977 | if (addr_same(&tm->tcpm_addr, &addr)) { |
| 978 | *pp = tm->tcpm_next; |
| 979 | break; |
| 980 | } |
| 981 | } |
| 982 | spin_unlock_bh(&tcp_metrics_lock); |
| 983 | if (!tm) |
| 984 | return -ESRCH; |
| 985 | kfree_rcu(tm, rcu_head); |
| 986 | return 0; |
| 987 | } |
| 988 | |
| 989 | static struct genl_ops tcp_metrics_nl_ops[] = { |
| 990 | { |
| 991 | .cmd = TCP_METRICS_CMD_GET, |
| 992 | .doit = tcp_metrics_nl_cmd_get, |
| 993 | .dumpit = tcp_metrics_nl_dump, |
| 994 | .policy = tcp_metrics_nl_policy, |
| 995 | .flags = GENL_ADMIN_PERM, |
| 996 | }, |
| 997 | { |
| 998 | .cmd = TCP_METRICS_CMD_DEL, |
| 999 | .doit = tcp_metrics_nl_cmd_del, |
| 1000 | .policy = tcp_metrics_nl_policy, |
| 1001 | .flags = GENL_ADMIN_PERM, |
| 1002 | }, |
| 1003 | }; |
| 1004 | |
Eric Dumazet | 5815d5e | 2012-07-19 23:02:34 +0000 | [diff] [blame] | 1005 | static unsigned int tcpmhash_entries; |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 1006 | static int __init set_tcpmhash_entries(char *str) |
| 1007 | { |
| 1008 | ssize_t ret; |
| 1009 | |
| 1010 | if (!str) |
| 1011 | return 0; |
| 1012 | |
Eric Dumazet | 5815d5e | 2012-07-19 23:02:34 +0000 | [diff] [blame] | 1013 | ret = kstrtouint(str, 0, &tcpmhash_entries); |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 1014 | if (ret) |
| 1015 | return 0; |
| 1016 | |
| 1017 | return 1; |
| 1018 | } |
| 1019 | __setup("tcpmhash_entries=", set_tcpmhash_entries); |
| 1020 | |
| 1021 | static int __net_init tcp_net_metrics_init(struct net *net) |
| 1022 | { |
Eric Dumazet | 5815d5e | 2012-07-19 23:02:34 +0000 | [diff] [blame] | 1023 | size_t size; |
| 1024 | unsigned int slots; |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 1025 | |
| 1026 | slots = tcpmhash_entries; |
| 1027 | if (!slots) { |
| 1028 | if (totalram_pages >= 128 * 1024) |
| 1029 | slots = 16 * 1024; |
| 1030 | else |
| 1031 | slots = 8 * 1024; |
| 1032 | } |
| 1033 | |
Eric Dumazet | 5815d5e | 2012-07-19 23:02:34 +0000 | [diff] [blame] | 1034 | net->ipv4.tcp_metrics_hash_log = order_base_2(slots); |
| 1035 | size = sizeof(struct tcpm_hash_bucket) << net->ipv4.tcp_metrics_hash_log; |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 1036 | |
| 1037 | net->ipv4.tcp_metrics_hash = kzalloc(size, GFP_KERNEL); |
| 1038 | if (!net->ipv4.tcp_metrics_hash) |
| 1039 | return -ENOMEM; |
| 1040 | |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 1041 | return 0; |
| 1042 | } |
| 1043 | |
| 1044 | static void __net_exit tcp_net_metrics_exit(struct net *net) |
| 1045 | { |
Eric Dumazet | 3647101 | 2012-08-09 11:19:13 +0200 | [diff] [blame] | 1046 | unsigned int i; |
| 1047 | |
| 1048 | for (i = 0; i < (1U << net->ipv4.tcp_metrics_hash_log) ; i++) { |
| 1049 | struct tcp_metrics_block *tm, *next; |
| 1050 | |
| 1051 | tm = rcu_dereference_protected(net->ipv4.tcp_metrics_hash[i].chain, 1); |
| 1052 | while (tm) { |
| 1053 | next = rcu_dereference_protected(tm->tcpm_next, 1); |
| 1054 | kfree(tm); |
| 1055 | tm = next; |
| 1056 | } |
| 1057 | } |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 1058 | kfree(net->ipv4.tcp_metrics_hash); |
| 1059 | } |
| 1060 | |
| 1061 | static __net_initdata struct pernet_operations tcp_net_metrics_ops = { |
| 1062 | .init = tcp_net_metrics_init, |
| 1063 | .exit = tcp_net_metrics_exit, |
| 1064 | }; |
| 1065 | |
| 1066 | void __init tcp_metrics_init(void) |
| 1067 | { |
Julian Anastasov | d23ff70 | 2012-09-04 11:03:15 +0000 | [diff] [blame] | 1068 | int ret; |
| 1069 | |
| 1070 | ret = register_pernet_subsys(&tcp_net_metrics_ops); |
| 1071 | if (ret < 0) |
| 1072 | goto cleanup; |
| 1073 | ret = genl_register_family_with_ops(&tcp_metrics_nl_family, |
| 1074 | tcp_metrics_nl_ops, |
| 1075 | ARRAY_SIZE(tcp_metrics_nl_ops)); |
| 1076 | if (ret < 0) |
| 1077 | goto cleanup_subsys; |
| 1078 | return; |
| 1079 | |
| 1080 | cleanup_subsys: |
| 1081 | unregister_pernet_subsys(&tcp_net_metrics_ops); |
| 1082 | |
| 1083 | cleanup: |
| 1084 | return; |
David S. Miller | 51c5d0c | 2012-07-10 00:49:14 -0700 | [diff] [blame] | 1085 | } |