Commit | Line | Data |
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f870fa0b MM |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* Multipath TCP | |
3 | * | |
4 | * Copyright (c) 2017 - 2019, Intel Corporation. | |
5 | */ | |
6 | ||
7 | #define pr_fmt(fmt) "MPTCP: " fmt | |
8 | ||
9 | #include <linux/kernel.h> | |
10 | #include <linux/module.h> | |
11 | #include <linux/netdevice.h> | |
7a6a6cbc PA |
12 | #include <linux/sched/signal.h> |
13 | #include <linux/atomic.h> | |
f870fa0b MM |
14 | #include <net/sock.h> |
15 | #include <net/inet_common.h> | |
16 | #include <net/inet_hashtables.h> | |
17 | #include <net/protocol.h> | |
18 | #include <net/tcp.h> | |
3721b9b6 | 19 | #include <net/tcp_states.h> |
cf7da0d6 PK |
20 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
21 | #include <net/transp_v6.h> | |
22 | #endif | |
f870fa0b | 23 | #include <net/mptcp.h> |
e16163b6 | 24 | #include <net/xfrm.h> |
644807e3 | 25 | #include <asm/ioctls.h> |
f870fa0b | 26 | #include "protocol.h" |
fc518953 | 27 | #include "mib.h" |
f870fa0b | 28 | |
e10a9892 GT |
29 | #define CREATE_TRACE_POINTS |
30 | #include <trace/events/mptcp.h> | |
31 | ||
b0519de8 FW |
32 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
33 | struct mptcp6_sock { | |
34 | struct mptcp_sock msk; | |
35 | struct ipv6_pinfo np; | |
36 | }; | |
37 | #endif | |
38 | ||
b7f653b2 FW |
39 | enum { |
40 | MPTCP_CMSG_TS = BIT(0), | |
2c9e7765 | 41 | MPTCP_CMSG_INQ = BIT(1), |
b7f653b2 FW |
42 | }; |
43 | ||
91b6d325 | 44 | static struct percpu_counter mptcp_sockets_allocated ____cacheline_aligned_in_smp; |
d027236c | 45 | |
e16163b6 | 46 | static void __mptcp_destroy_sock(struct sock *sk); |
d9ca1de8 | 47 | static void __mptcp_check_send_data_fin(struct sock *sk); |
e16163b6 | 48 | |
b19bc294 PA |
49 | DEFINE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); |
50 | static struct net_device mptcp_napi_dev; | |
51 | ||
6f8a612a FW |
52 | /* Returns end sequence number of the receiver's advertised window */ |
53 | static u64 mptcp_wnd_end(const struct mptcp_sock *msk) | |
54 | { | |
7439d687 | 55 | return READ_ONCE(msk->wnd_end); |
6f8a612a FW |
56 | } |
57 | ||
d2f77c53 | 58 | static bool mptcp_is_tcpsk(struct sock *sk) |
0b4f33de FW |
59 | { |
60 | struct socket *sock = sk->sk_socket; | |
61 | ||
0b4f33de FW |
62 | if (unlikely(sk->sk_prot == &tcp_prot)) { |
63 | /* we are being invoked after mptcp_accept() has | |
64 | * accepted a non-mp-capable flow: sk is a tcp_sk, | |
65 | * not an mptcp one. | |
66 | * | |
67 | * Hand the socket over to tcp so all further socket ops | |
68 | * bypass mptcp. | |
69 | */ | |
70 | sock->ops = &inet_stream_ops; | |
d2f77c53 | 71 | return true; |
0b4f33de FW |
72 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
73 | } else if (unlikely(sk->sk_prot == &tcpv6_prot)) { | |
74 | sock->ops = &inet6_stream_ops; | |
d2f77c53 | 75 | return true; |
0b4f33de FW |
76 | #endif |
77 | } | |
78 | ||
d2f77c53 | 79 | return false; |
0b4f33de FW |
80 | } |
81 | ||
fa68018d | 82 | static int __mptcp_socket_create(struct mptcp_sock *msk) |
2303f994 PK |
83 | { |
84 | struct mptcp_subflow_context *subflow; | |
85 | struct sock *sk = (struct sock *)msk; | |
86 | struct socket *ssock; | |
87 | int err; | |
88 | ||
6bc1fe7d | 89 | err = mptcp_subflow_create_socket(sk, sk->sk_family, &ssock); |
2303f994 | 90 | if (err) |
fa68018d | 91 | return err; |
2303f994 | 92 | |
8ab183de | 93 | msk->first = ssock->sk; |
2303f994 PK |
94 | msk->subflow = ssock; |
95 | subflow = mptcp_subflow_ctx(ssock->sk); | |
cec37a6e | 96 | list_add(&subflow->node, &msk->conn_list); |
e16163b6 | 97 | sock_hold(ssock->sk); |
2303f994 | 98 | subflow->request_mptcp = 1; |
4cf86ae8 PA |
99 | |
100 | /* This is the first subflow, always with id 0 */ | |
101 | subflow->local_id_valid = 1; | |
866f26f2 | 102 | mptcp_sock_graft(msk->first, sk->sk_socket); |
e1ff9e82 | 103 | |
fa68018d | 104 | return 0; |
2303f994 PK |
105 | } |
106 | ||
ddb1a072 PA |
107 | /* If the MPC handshake is not started, returns the first subflow, |
108 | * eventually allocating it. | |
109 | */ | |
110 | struct socket *__mptcp_nmpc_socket(struct mptcp_sock *msk) | |
111 | { | |
112 | struct sock *sk = (struct sock *)msk; | |
113 | int ret; | |
114 | ||
115 | if (!((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) | |
116 | return ERR_PTR(-EINVAL); | |
117 | ||
118 | if (!msk->subflow) { | |
119 | if (msk->first) | |
120 | return ERR_PTR(-EINVAL); | |
121 | ||
122 | ret = __mptcp_socket_create(msk); | |
123 | if (ret) | |
124 | return ERR_PTR(ret); | |
125 | ||
126 | mptcp_sockopt_sync(msk, msk->first); | |
127 | } | |
128 | ||
129 | return msk->subflow; | |
130 | } | |
131 | ||
ab174ad8 PA |
132 | static void mptcp_drop(struct sock *sk, struct sk_buff *skb) |
133 | { | |
134 | sk_drops_add(sk, skb); | |
135 | __kfree_skb(skb); | |
136 | } | |
137 | ||
6511882c PA |
138 | static void mptcp_rmem_charge(struct sock *sk, int size) |
139 | { | |
140 | mptcp_sk(sk)->rmem_fwd_alloc -= size; | |
141 | } | |
142 | ||
8268ed4c PA |
143 | static bool mptcp_try_coalesce(struct sock *sk, struct sk_buff *to, |
144 | struct sk_buff *from) | |
145 | { | |
146 | bool fragstolen; | |
147 | int delta; | |
148 | ||
149 | if (MPTCP_SKB_CB(from)->offset || | |
150 | !skb_try_coalesce(to, from, &fragstolen, &delta)) | |
151 | return false; | |
152 | ||
06242e44 PA |
153 | pr_debug("colesced seq %llx into %llx new len %d new end seq %llx", |
154 | MPTCP_SKB_CB(from)->map_seq, MPTCP_SKB_CB(to)->map_seq, | |
155 | to->len, MPTCP_SKB_CB(from)->end_seq); | |
ab174ad8 | 156 | MPTCP_SKB_CB(to)->end_seq = MPTCP_SKB_CB(from)->end_seq; |
7288ff6e PA |
157 | |
158 | /* note the fwd memory can reach a negative value after accounting | |
159 | * for the delta, but the later skb free will restore a non | |
160 | * negative one | |
161 | */ | |
8268ed4c | 162 | atomic_add(delta, &sk->sk_rmem_alloc); |
6511882c | 163 | mptcp_rmem_charge(sk, delta); |
7288ff6e PA |
164 | kfree_skb_partial(from, fragstolen); |
165 | ||
8268ed4c PA |
166 | return true; |
167 | } | |
168 | ||
ab174ad8 PA |
169 | static bool mptcp_ooo_try_coalesce(struct mptcp_sock *msk, struct sk_buff *to, |
170 | struct sk_buff *from) | |
171 | { | |
172 | if (MPTCP_SKB_CB(from)->map_seq != MPTCP_SKB_CB(to)->end_seq) | |
173 | return false; | |
174 | ||
175 | return mptcp_try_coalesce((struct sock *)msk, to, from); | |
176 | } | |
177 | ||
6511882c PA |
178 | static void __mptcp_rmem_reclaim(struct sock *sk, int amount) |
179 | { | |
100fdd1f ED |
180 | amount >>= PAGE_SHIFT; |
181 | mptcp_sk(sk)->rmem_fwd_alloc -= amount << PAGE_SHIFT; | |
6511882c PA |
182 | __sk_mem_reduce_allocated(sk, amount); |
183 | } | |
184 | ||
185 | static void mptcp_rmem_uncharge(struct sock *sk, int size) | |
186 | { | |
187 | struct mptcp_sock *msk = mptcp_sk(sk); | |
188 | int reclaimable; | |
189 | ||
190 | msk->rmem_fwd_alloc += size; | |
191 | reclaimable = msk->rmem_fwd_alloc - sk_unused_reserved_mem(sk); | |
192 | ||
193 | /* see sk_mem_uncharge() for the rationale behind the following schema */ | |
d24141fe PA |
194 | if (unlikely(reclaimable >= PAGE_SIZE)) |
195 | __mptcp_rmem_reclaim(sk, reclaimable); | |
6511882c PA |
196 | } |
197 | ||
198 | static void mptcp_rfree(struct sk_buff *skb) | |
199 | { | |
200 | unsigned int len = skb->truesize; | |
201 | struct sock *sk = skb->sk; | |
202 | ||
203 | atomic_sub(len, &sk->sk_rmem_alloc); | |
204 | mptcp_rmem_uncharge(sk, len); | |
205 | } | |
206 | ||
36b122ba | 207 | void mptcp_set_owner_r(struct sk_buff *skb, struct sock *sk) |
6511882c PA |
208 | { |
209 | skb_orphan(skb); | |
210 | skb->sk = sk; | |
211 | skb->destructor = mptcp_rfree; | |
212 | atomic_add(skb->truesize, &sk->sk_rmem_alloc); | |
213 | mptcp_rmem_charge(sk, skb->truesize); | |
214 | } | |
215 | ||
ab174ad8 PA |
216 | /* "inspired" by tcp_data_queue_ofo(), main differences: |
217 | * - use mptcp seqs | |
218 | * - don't cope with sacks | |
219 | */ | |
220 | static void mptcp_data_queue_ofo(struct mptcp_sock *msk, struct sk_buff *skb) | |
221 | { | |
222 | struct sock *sk = (struct sock *)msk; | |
223 | struct rb_node **p, *parent; | |
224 | u64 seq, end_seq, max_seq; | |
225 | struct sk_buff *skb1; | |
226 | ||
227 | seq = MPTCP_SKB_CB(skb)->map_seq; | |
228 | end_seq = MPTCP_SKB_CB(skb)->end_seq; | |
f3589be0 | 229 | max_seq = atomic64_read(&msk->rcv_wnd_sent); |
ab174ad8 | 230 | |
06242e44 PA |
231 | pr_debug("msk=%p seq=%llx limit=%llx empty=%d", msk, seq, max_seq, |
232 | RB_EMPTY_ROOT(&msk->out_of_order_queue)); | |
fa3fe2b1 | 233 | if (after64(end_seq, max_seq)) { |
ab174ad8 PA |
234 | /* out of window */ |
235 | mptcp_drop(sk, skb); | |
fa3fe2b1 FW |
236 | pr_debug("oow by %lld, rcv_wnd_sent %llu\n", |
237 | (unsigned long long)end_seq - (unsigned long)max_seq, | |
f3589be0 | 238 | (unsigned long long)atomic64_read(&msk->rcv_wnd_sent)); |
06242e44 | 239 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_NODSSWINDOW); |
ab174ad8 PA |
240 | return; |
241 | } | |
242 | ||
243 | p = &msk->out_of_order_queue.rb_node; | |
06242e44 | 244 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_OFOQUEUE); |
ab174ad8 PA |
245 | if (RB_EMPTY_ROOT(&msk->out_of_order_queue)) { |
246 | rb_link_node(&skb->rbnode, NULL, p); | |
247 | rb_insert_color(&skb->rbnode, &msk->out_of_order_queue); | |
248 | msk->ooo_last_skb = skb; | |
249 | goto end; | |
250 | } | |
251 | ||
252 | /* with 2 subflows, adding at end of ooo queue is quite likely | |
253 | * Use of ooo_last_skb avoids the O(Log(N)) rbtree lookup. | |
254 | */ | |
06242e44 PA |
255 | if (mptcp_ooo_try_coalesce(msk, msk->ooo_last_skb, skb)) { |
256 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_OFOMERGE); | |
257 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_OFOQUEUETAIL); | |
ab174ad8 | 258 | return; |
06242e44 | 259 | } |
ab174ad8 PA |
260 | |
261 | /* Can avoid an rbtree lookup if we are adding skb after ooo_last_skb */ | |
262 | if (!before64(seq, MPTCP_SKB_CB(msk->ooo_last_skb)->end_seq)) { | |
06242e44 | 263 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_OFOQUEUETAIL); |
ab174ad8 PA |
264 | parent = &msk->ooo_last_skb->rbnode; |
265 | p = &parent->rb_right; | |
266 | goto insert; | |
267 | } | |
268 | ||
269 | /* Find place to insert this segment. Handle overlaps on the way. */ | |
270 | parent = NULL; | |
271 | while (*p) { | |
272 | parent = *p; | |
273 | skb1 = rb_to_skb(parent); | |
274 | if (before64(seq, MPTCP_SKB_CB(skb1)->map_seq)) { | |
275 | p = &parent->rb_left; | |
276 | continue; | |
277 | } | |
278 | if (before64(seq, MPTCP_SKB_CB(skb1)->end_seq)) { | |
279 | if (!after64(end_seq, MPTCP_SKB_CB(skb1)->end_seq)) { | |
280 | /* All the bits are present. Drop. */ | |
281 | mptcp_drop(sk, skb); | |
06242e44 | 282 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DUPDATA); |
ab174ad8 PA |
283 | return; |
284 | } | |
285 | if (after64(seq, MPTCP_SKB_CB(skb1)->map_seq)) { | |
286 | /* partial overlap: | |
287 | * | skb | | |
288 | * | skb1 | | |
289 | * continue traversing | |
290 | */ | |
291 | } else { | |
292 | /* skb's seq == skb1's seq and skb covers skb1. | |
293 | * Replace skb1 with skb. | |
294 | */ | |
295 | rb_replace_node(&skb1->rbnode, &skb->rbnode, | |
296 | &msk->out_of_order_queue); | |
297 | mptcp_drop(sk, skb1); | |
06242e44 | 298 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DUPDATA); |
ab174ad8 PA |
299 | goto merge_right; |
300 | } | |
301 | } else if (mptcp_ooo_try_coalesce(msk, skb1, skb)) { | |
06242e44 | 302 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_OFOMERGE); |
ab174ad8 PA |
303 | return; |
304 | } | |
305 | p = &parent->rb_right; | |
306 | } | |
06242e44 | 307 | |
ab174ad8 PA |
308 | insert: |
309 | /* Insert segment into RB tree. */ | |
310 | rb_link_node(&skb->rbnode, parent, p); | |
311 | rb_insert_color(&skb->rbnode, &msk->out_of_order_queue); | |
312 | ||
313 | merge_right: | |
314 | /* Remove other segments covered by skb. */ | |
315 | while ((skb1 = skb_rb_next(skb)) != NULL) { | |
316 | if (before64(end_seq, MPTCP_SKB_CB(skb1)->end_seq)) | |
317 | break; | |
318 | rb_erase(&skb1->rbnode, &msk->out_of_order_queue); | |
319 | mptcp_drop(sk, skb1); | |
06242e44 | 320 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DUPDATA); |
ab174ad8 PA |
321 | } |
322 | /* If there is no skb after us, we are the last_skb ! */ | |
323 | if (!skb1) | |
324 | msk->ooo_last_skb = skb; | |
325 | ||
326 | end: | |
327 | skb_condense(skb); | |
6511882c PA |
328 | mptcp_set_owner_r(skb, sk); |
329 | } | |
330 | ||
331 | static bool mptcp_rmem_schedule(struct sock *sk, struct sock *ssk, int size) | |
332 | { | |
333 | struct mptcp_sock *msk = mptcp_sk(sk); | |
334 | int amt, amount; | |
335 | ||
69d93dae | 336 | if (size <= msk->rmem_fwd_alloc) |
6511882c PA |
337 | return true; |
338 | ||
69d93dae | 339 | size -= msk->rmem_fwd_alloc; |
6511882c | 340 | amt = sk_mem_pages(size); |
100fdd1f | 341 | amount = amt << PAGE_SHIFT; |
4aaa1685 PA |
342 | if (!__sk_mem_raise_allocated(sk, size, amt, SK_MEM_RECV)) |
343 | return false; | |
6511882c | 344 | |
4aaa1685 | 345 | msk->rmem_fwd_alloc += amount; |
6511882c | 346 | return true; |
ab174ad8 PA |
347 | } |
348 | ||
349 | static bool __mptcp_move_skb(struct mptcp_sock *msk, struct sock *ssk, | |
350 | struct sk_buff *skb, unsigned int offset, | |
351 | size_t copy_len) | |
6771bfd9 | 352 | { |
ab174ad8 | 353 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); |
6771bfd9 | 354 | struct sock *sk = (struct sock *)msk; |
4e637c70 | 355 | struct sk_buff *tail; |
b7f653b2 | 356 | bool has_rxtstamp; |
6771bfd9 FW |
357 | |
358 | __skb_unlink(skb, &ssk->sk_receive_queue); | |
6771bfd9 | 359 | |
4e637c70 FW |
360 | skb_ext_reset(skb); |
361 | skb_orphan(skb); | |
ab174ad8 | 362 | |
9c3f94e1 | 363 | /* try to fetch required memory from subflow */ |
6511882c PA |
364 | if (!mptcp_rmem_schedule(sk, ssk, skb->truesize)) |
365 | goto drop; | |
9c3f94e1 | 366 | |
b7f653b2 FW |
367 | has_rxtstamp = TCP_SKB_CB(skb)->has_rxtstamp; |
368 | ||
ab174ad8 PA |
369 | /* the skb map_seq accounts for the skb offset: |
370 | * mptcp_subflow_get_mapped_dsn() is based on the current tp->copied_seq | |
371 | * value | |
372 | */ | |
373 | MPTCP_SKB_CB(skb)->map_seq = mptcp_subflow_get_mapped_dsn(subflow); | |
374 | MPTCP_SKB_CB(skb)->end_seq = MPTCP_SKB_CB(skb)->map_seq + copy_len; | |
8268ed4c | 375 | MPTCP_SKB_CB(skb)->offset = offset; |
b7f653b2 | 376 | MPTCP_SKB_CB(skb)->has_rxtstamp = has_rxtstamp; |
4e637c70 | 377 | |
ab174ad8 PA |
378 | if (MPTCP_SKB_CB(skb)->map_seq == msk->ack_seq) { |
379 | /* in sequence */ | |
8b0308fe | 380 | WRITE_ONCE(msk->ack_seq, msk->ack_seq + copy_len); |
ab174ad8 PA |
381 | tail = skb_peek_tail(&sk->sk_receive_queue); |
382 | if (tail && mptcp_try_coalesce(sk, tail, skb)) | |
383 | return true; | |
4e637c70 | 384 | |
6511882c | 385 | mptcp_set_owner_r(skb, sk); |
ab174ad8 PA |
386 | __skb_queue_tail(&sk->sk_receive_queue, skb); |
387 | return true; | |
388 | } else if (after64(MPTCP_SKB_CB(skb)->map_seq, msk->ack_seq)) { | |
389 | mptcp_data_queue_ofo(msk, skb); | |
390 | return false; | |
391 | } | |
392 | ||
393 | /* old data, keep it simple and drop the whole pkt, sender | |
394 | * will retransmit as needed, if needed. | |
395 | */ | |
06242e44 | 396 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DUPDATA); |
9c3f94e1 | 397 | drop: |
ab174ad8 PA |
398 | mptcp_drop(sk, skb); |
399 | return false; | |
6771bfd9 FW |
400 | } |
401 | ||
16a9a9da MM |
402 | static void mptcp_stop_timer(struct sock *sk) |
403 | { | |
404 | struct inet_connection_sock *icsk = inet_csk(sk); | |
405 | ||
406 | sk_stop_timer(sk, &icsk->icsk_retransmit_timer); | |
407 | mptcp_sk(sk)->timer_ival = 0; | |
408 | } | |
409 | ||
e16163b6 PA |
410 | static void mptcp_close_wake_up(struct sock *sk) |
411 | { | |
412 | if (sock_flag(sk, SOCK_DEAD)) | |
413 | return; | |
414 | ||
415 | sk->sk_state_change(sk); | |
416 | if (sk->sk_shutdown == SHUTDOWN_MASK || | |
417 | sk->sk_state == TCP_CLOSE) | |
418 | sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_HUP); | |
419 | else | |
420 | sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); | |
421 | } | |
422 | ||
6e628cd3 | 423 | static bool mptcp_pending_data_fin_ack(struct sock *sk) |
16a9a9da MM |
424 | { |
425 | struct mptcp_sock *msk = mptcp_sk(sk); | |
426 | ||
6e628cd3 PA |
427 | return !__mptcp_check_fallback(msk) && |
428 | ((1 << sk->sk_state) & | |
429 | (TCPF_FIN_WAIT1 | TCPF_CLOSING | TCPF_LAST_ACK)) && | |
430 | msk->write_seq == READ_ONCE(msk->snd_una); | |
431 | } | |
432 | ||
433 | static void mptcp_check_data_fin_ack(struct sock *sk) | |
434 | { | |
435 | struct mptcp_sock *msk = mptcp_sk(sk); | |
16a9a9da MM |
436 | |
437 | /* Look for an acknowledged DATA_FIN */ | |
6e628cd3 | 438 | if (mptcp_pending_data_fin_ack(sk)) { |
16a9a9da MM |
439 | WRITE_ONCE(msk->snd_data_fin_enable, 0); |
440 | ||
441 | switch (sk->sk_state) { | |
442 | case TCP_FIN_WAIT1: | |
443 | inet_sk_state_store(sk, TCP_FIN_WAIT2); | |
16a9a9da MM |
444 | break; |
445 | case TCP_CLOSING: | |
16a9a9da MM |
446 | case TCP_LAST_ACK: |
447 | inet_sk_state_store(sk, TCP_CLOSE); | |
16a9a9da MM |
448 | break; |
449 | } | |
450 | ||
e16163b6 | 451 | mptcp_close_wake_up(sk); |
16a9a9da MM |
452 | } |
453 | } | |
454 | ||
3721b9b6 MM |
455 | static bool mptcp_pending_data_fin(struct sock *sk, u64 *seq) |
456 | { | |
457 | struct mptcp_sock *msk = mptcp_sk(sk); | |
458 | ||
459 | if (READ_ONCE(msk->rcv_data_fin) && | |
460 | ((1 << sk->sk_state) & | |
461 | (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2))) { | |
462 | u64 rcv_data_fin_seq = READ_ONCE(msk->rcv_data_fin_seq); | |
463 | ||
464 | if (msk->ack_seq == rcv_data_fin_seq) { | |
465 | if (seq) | |
466 | *seq = rcv_data_fin_seq; | |
467 | ||
468 | return true; | |
469 | } | |
470 | } | |
471 | ||
472 | return false; | |
473 | } | |
474 | ||
403a40f2 | 475 | static void mptcp_set_datafin_timeout(struct sock *sk) |
6477dd39 MM |
476 | { |
477 | struct inet_connection_sock *icsk = inet_csk(sk); | |
877d11f0 | 478 | u32 retransmits; |
6477dd39 | 479 | |
877d11f0 MM |
480 | retransmits = min_t(u32, icsk->icsk_retransmits, |
481 | ilog2(TCP_RTO_MAX / TCP_RTO_MIN)); | |
482 | ||
483 | mptcp_sk(sk)->timer_ival = TCP_RTO_MIN << retransmits; | |
6477dd39 MM |
484 | } |
485 | ||
33d41c9c | 486 | static void __mptcp_set_timeout(struct sock *sk, long tout) |
3721b9b6 | 487 | { |
3721b9b6 MM |
488 | mptcp_sk(sk)->timer_ival = tout > 0 ? tout : TCP_RTO_MIN; |
489 | } | |
490 | ||
33d41c9c PA |
491 | static long mptcp_timeout_from_subflow(const struct mptcp_subflow_context *subflow) |
492 | { | |
493 | const struct sock *ssk = mptcp_subflow_tcp_sock(subflow); | |
494 | ||
71b7dec2 PA |
495 | return inet_csk(ssk)->icsk_pending && !subflow->stale_count ? |
496 | inet_csk(ssk)->icsk_timeout - jiffies : 0; | |
33d41c9c PA |
497 | } |
498 | ||
499 | static void mptcp_set_timeout(struct sock *sk) | |
500 | { | |
501 | struct mptcp_subflow_context *subflow; | |
502 | long tout = 0; | |
503 | ||
504 | mptcp_for_each_subflow(mptcp_sk(sk), subflow) | |
505 | tout = max(tout, mptcp_timeout_from_subflow(subflow)); | |
506 | __mptcp_set_timeout(sk, tout); | |
507 | } | |
508 | ||
76a13b31 | 509 | static inline bool tcp_can_send_ack(const struct sock *ssk) |
fd897679 PA |
510 | { |
511 | return !((1 << inet_sk_state_load(ssk)) & | |
20bc80b6 | 512 | (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_TIME_WAIT | TCPF_CLOSE | TCPF_LISTEN)); |
fd897679 PA |
513 | } |
514 | ||
a6574302 MM |
515 | void __mptcp_subflow_send_ack(struct sock *ssk) |
516 | { | |
517 | if (tcp_can_send_ack(ssk)) | |
518 | tcp_send_ack(ssk); | |
519 | } | |
520 | ||
f5360e9b | 521 | static void mptcp_subflow_send_ack(struct sock *ssk) |
340fa666 MM |
522 | { |
523 | bool slow; | |
524 | ||
525 | slow = lock_sock_fast(ssk); | |
a6574302 | 526 | __mptcp_subflow_send_ack(ssk); |
340fa666 MM |
527 | unlock_sock_fast(ssk, slow); |
528 | } | |
529 | ||
fd897679 | 530 | static void mptcp_send_ack(struct mptcp_sock *msk) |
7ed90803 PA |
531 | { |
532 | struct mptcp_subflow_context *subflow; | |
533 | ||
340fa666 MM |
534 | mptcp_for_each_subflow(msk, subflow) |
535 | mptcp_subflow_send_ack(mptcp_subflow_tcp_sock(subflow)); | |
fd897679 PA |
536 | } |
537 | ||
fde56eea | 538 | static void mptcp_subflow_cleanup_rbuf(struct sock *ssk) |
fd897679 | 539 | { |
75e908c3 | 540 | bool slow; |
fd897679 | 541 | |
75e908c3 | 542 | slow = lock_sock_fast(ssk); |
fde56eea | 543 | if (tcp_can_send_ack(ssk)) |
fd897679 | 544 | tcp_cleanup_rbuf(ssk, 1); |
75e908c3 | 545 | unlock_sock_fast(ssk, slow); |
fde56eea PA |
546 | } |
547 | ||
548 | static bool mptcp_subflow_could_cleanup(const struct sock *ssk, bool rx_empty) | |
549 | { | |
550 | const struct inet_connection_sock *icsk = inet_csk(ssk); | |
c4512c63 | 551 | u8 ack_pending = READ_ONCE(icsk->icsk_ack.pending); |
fde56eea PA |
552 | const struct tcp_sock *tp = tcp_sk(ssk); |
553 | ||
554 | return (ack_pending & ICSK_ACK_SCHED) && | |
555 | ((READ_ONCE(tp->rcv_nxt) - READ_ONCE(tp->rcv_wup) > | |
556 | READ_ONCE(icsk->icsk_ack.rcv_mss)) || | |
557 | (rx_empty && ack_pending & | |
558 | (ICSK_ACK_PUSHED2 | ICSK_ACK_PUSHED))); | |
fd897679 PA |
559 | } |
560 | ||
561 | static void mptcp_cleanup_rbuf(struct mptcp_sock *msk) | |
562 | { | |
e3859603 | 563 | int old_space = READ_ONCE(msk->old_wspace); |
fd897679 | 564 | struct mptcp_subflow_context *subflow; |
e3859603 | 565 | struct sock *sk = (struct sock *)msk; |
fde56eea PA |
566 | int space = __mptcp_space(sk); |
567 | bool cleanup, rx_empty; | |
e3859603 | 568 | |
fde56eea | 569 | cleanup = (space > 0) && (space >= (old_space << 1)); |
ce599c51 | 570 | rx_empty = !__mptcp_rmem(sk); |
fd897679 | 571 | |
fde56eea PA |
572 | mptcp_for_each_subflow(msk, subflow) { |
573 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); | |
fd897679 | 574 | |
fde56eea PA |
575 | if (cleanup || mptcp_subflow_could_cleanup(ssk, rx_empty)) |
576 | mptcp_subflow_cleanup_rbuf(ssk); | |
7ed90803 PA |
577 | } |
578 | } | |
579 | ||
580 | static bool mptcp_check_data_fin(struct sock *sk) | |
3721b9b6 MM |
581 | { |
582 | struct mptcp_sock *msk = mptcp_sk(sk); | |
583 | u64 rcv_data_fin_seq; | |
7ed90803 | 584 | bool ret = false; |
3721b9b6 | 585 | |
781bf13d | 586 | if (__mptcp_check_fallback(msk)) |
7ed90803 | 587 | return ret; |
3721b9b6 MM |
588 | |
589 | /* Need to ack a DATA_FIN received from a peer while this side | |
590 | * of the connection is in ESTABLISHED, FIN_WAIT1, or FIN_WAIT2. | |
591 | * msk->rcv_data_fin was set when parsing the incoming options | |
592 | * at the subflow level and the msk lock was not held, so this | |
593 | * is the first opportunity to act on the DATA_FIN and change | |
594 | * the msk state. | |
595 | * | |
596 | * If we are caught up to the sequence number of the incoming | |
597 | * DATA_FIN, send the DATA_ACK now and do state transition. If | |
598 | * not caught up, do nothing and let the recv code send DATA_ACK | |
599 | * when catching up. | |
600 | */ | |
601 | ||
602 | if (mptcp_pending_data_fin(sk, &rcv_data_fin_seq)) { | |
917944da | 603 | WRITE_ONCE(msk->ack_seq, msk->ack_seq + 1); |
3721b9b6 MM |
604 | WRITE_ONCE(msk->rcv_data_fin, 0); |
605 | ||
606 | sk->sk_shutdown |= RCV_SHUTDOWN; | |
16a9a9da | 607 | smp_mb__before_atomic(); /* SHUTDOWN must be visible first */ |
3721b9b6 MM |
608 | |
609 | switch (sk->sk_state) { | |
610 | case TCP_ESTABLISHED: | |
611 | inet_sk_state_store(sk, TCP_CLOSE_WAIT); | |
612 | break; | |
613 | case TCP_FIN_WAIT1: | |
614 | inet_sk_state_store(sk, TCP_CLOSING); | |
615 | break; | |
616 | case TCP_FIN_WAIT2: | |
617 | inet_sk_state_store(sk, TCP_CLOSE); | |
3721b9b6 MM |
618 | break; |
619 | default: | |
620 | /* Other states not expected */ | |
621 | WARN_ON_ONCE(1); | |
622 | break; | |
623 | } | |
624 | ||
7ed90803 | 625 | ret = true; |
fd897679 | 626 | mptcp_send_ack(msk); |
e16163b6 | 627 | mptcp_close_wake_up(sk); |
3721b9b6 | 628 | } |
7ed90803 | 629 | return ret; |
3721b9b6 MM |
630 | } |
631 | ||
6771bfd9 FW |
632 | static bool __mptcp_move_skbs_from_subflow(struct mptcp_sock *msk, |
633 | struct sock *ssk, | |
634 | unsigned int *bytes) | |
635 | { | |
636 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
600911ff | 637 | struct sock *sk = (struct sock *)msk; |
6771bfd9 FW |
638 | unsigned int moved = 0; |
639 | bool more_data_avail; | |
640 | struct tcp_sock *tp; | |
641 | bool done = false; | |
13c7ba0c FW |
642 | int sk_rbuf; |
643 | ||
644 | sk_rbuf = READ_ONCE(sk->sk_rcvbuf); | |
645 | ||
646 | if (!(sk->sk_userlocks & SOCK_RCVBUF_LOCK)) { | |
647 | int ssk_rbuf = READ_ONCE(ssk->sk_rcvbuf); | |
648 | ||
649 | if (unlikely(ssk_rbuf > sk_rbuf)) { | |
650 | WRITE_ONCE(sk->sk_rcvbuf, ssk_rbuf); | |
651 | sk_rbuf = ssk_rbuf; | |
652 | } | |
653 | } | |
600911ff | 654 | |
ab174ad8 | 655 | pr_debug("msk=%p ssk=%p", msk, ssk); |
6771bfd9 FW |
656 | tp = tcp_sk(ssk); |
657 | do { | |
658 | u32 map_remaining, offset; | |
659 | u32 seq = tp->copied_seq; | |
660 | struct sk_buff *skb; | |
661 | bool fin; | |
662 | ||
663 | /* try to move as much data as available */ | |
664 | map_remaining = subflow->map_data_len - | |
665 | mptcp_subflow_get_map_offset(subflow); | |
666 | ||
667 | skb = skb_peek(&ssk->sk_receive_queue); | |
d9fb8c50 | 668 | if (!skb) { |
d89e3ed7 PA |
669 | /* With racing move_skbs_to_msk() and __mptcp_move_skbs(), |
670 | * a different CPU can have already processed the pending | |
671 | * data, stop here or we can enter an infinite loop | |
d9fb8c50 PA |
672 | */ |
673 | if (!moved) | |
674 | done = true; | |
6771bfd9 | 675 | break; |
d9fb8c50 | 676 | } |
6771bfd9 | 677 | |
e1ff9e82 | 678 | if (__mptcp_check_fallback(msk)) { |
d89e3ed7 PA |
679 | /* Under fallback skbs have no MPTCP extension and TCP could |
680 | * collapse them between the dummy map creation and the | |
681 | * current dequeue. Be sure to adjust the map size. | |
e1ff9e82 DC |
682 | */ |
683 | map_remaining = skb->len; | |
684 | subflow->map_data_len = skb->len; | |
685 | } | |
686 | ||
6771bfd9 FW |
687 | offset = seq - TCP_SKB_CB(skb)->seq; |
688 | fin = TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN; | |
689 | if (fin) { | |
690 | done = true; | |
691 | seq++; | |
692 | } | |
693 | ||
694 | if (offset < skb->len) { | |
695 | size_t len = skb->len - offset; | |
696 | ||
697 | if (tp->urg_data) | |
698 | done = true; | |
699 | ||
ab174ad8 PA |
700 | if (__mptcp_move_skb(msk, ssk, skb, offset, len)) |
701 | moved += len; | |
6771bfd9 | 702 | seq += len; |
6771bfd9 FW |
703 | |
704 | if (WARN_ON_ONCE(map_remaining < len)) | |
705 | break; | |
706 | } else { | |
707 | WARN_ON_ONCE(!fin); | |
708 | sk_eat_skb(ssk, skb); | |
709 | done = true; | |
710 | } | |
711 | ||
712 | WRITE_ONCE(tp->copied_seq, seq); | |
713 | more_data_avail = mptcp_subflow_data_available(ssk); | |
600911ff | 714 | |
13c7ba0c | 715 | if (atomic_read(&sk->sk_rmem_alloc) > sk_rbuf) { |
600911ff FW |
716 | done = true; |
717 | break; | |
718 | } | |
6771bfd9 FW |
719 | } while (more_data_avail); |
720 | ||
6719331c | 721 | *bytes += moved; |
6771bfd9 FW |
722 | return done; |
723 | } | |
724 | ||
87952603 | 725 | static bool __mptcp_ofo_queue(struct mptcp_sock *msk) |
ab174ad8 PA |
726 | { |
727 | struct sock *sk = (struct sock *)msk; | |
728 | struct sk_buff *skb, *tail; | |
729 | bool moved = false; | |
730 | struct rb_node *p; | |
731 | u64 end_seq; | |
732 | ||
733 | p = rb_first(&msk->out_of_order_queue); | |
06242e44 | 734 | pr_debug("msk=%p empty=%d", msk, RB_EMPTY_ROOT(&msk->out_of_order_queue)); |
ab174ad8 PA |
735 | while (p) { |
736 | skb = rb_to_skb(p); | |
737 | if (after64(MPTCP_SKB_CB(skb)->map_seq, msk->ack_seq)) | |
738 | break; | |
739 | ||
740 | p = rb_next(p); | |
741 | rb_erase(&skb->rbnode, &msk->out_of_order_queue); | |
742 | ||
743 | if (unlikely(!after64(MPTCP_SKB_CB(skb)->end_seq, | |
744 | msk->ack_seq))) { | |
745 | mptcp_drop(sk, skb); | |
06242e44 | 746 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DUPDATA); |
ab174ad8 PA |
747 | continue; |
748 | } | |
749 | ||
750 | end_seq = MPTCP_SKB_CB(skb)->end_seq; | |
751 | tail = skb_peek_tail(&sk->sk_receive_queue); | |
752 | if (!tail || !mptcp_ooo_try_coalesce(msk, tail, skb)) { | |
753 | int delta = msk->ack_seq - MPTCP_SKB_CB(skb)->map_seq; | |
754 | ||
755 | /* skip overlapping data, if any */ | |
06242e44 PA |
756 | pr_debug("uncoalesced seq=%llx ack seq=%llx delta=%d", |
757 | MPTCP_SKB_CB(skb)->map_seq, msk->ack_seq, | |
758 | delta); | |
ab174ad8 | 759 | MPTCP_SKB_CB(skb)->offset += delta; |
2c9e7765 | 760 | MPTCP_SKB_CB(skb)->map_seq += delta; |
ab174ad8 PA |
761 | __skb_queue_tail(&sk->sk_receive_queue, skb); |
762 | } | |
763 | msk->ack_seq = end_seq; | |
764 | moved = true; | |
765 | } | |
766 | return moved; | |
767 | } | |
768 | ||
2e52213c FW |
769 | /* In most cases we will be able to lock the mptcp socket. If its already |
770 | * owned, we need to defer to the work queue to avoid ABBA deadlock. | |
771 | */ | |
99d1055c | 772 | static bool move_skbs_to_msk(struct mptcp_sock *msk, struct sock *ssk) |
2e52213c FW |
773 | { |
774 | struct sock *sk = (struct sock *)msk; | |
775 | unsigned int moved = 0; | |
776 | ||
87952603 PA |
777 | __mptcp_move_skbs_from_subflow(msk, ssk, &moved); |
778 | __mptcp_ofo_queue(msk); | |
499ada50 PA |
779 | if (unlikely(ssk->sk_err)) { |
780 | if (!sock_owned_by_user(sk)) | |
781 | __mptcp_error_report(sk); | |
782 | else | |
e9d09bac | 783 | __set_bit(MPTCP_ERROR_REPORT, &msk->cb_flags); |
499ada50 | 784 | } |
2e52213c | 785 | |
87952603 PA |
786 | /* If the moves have caught up with the DATA_FIN sequence number |
787 | * it's time to ack the DATA_FIN and change socket state, but | |
788 | * this is not a good place to change state. Let the workqueue | |
789 | * do it. | |
790 | */ | |
791 | if (mptcp_pending_data_fin(sk, NULL)) | |
792 | mptcp_schedule_work(sk); | |
99d1055c | 793 | return moved > 0; |
2e52213c FW |
794 | } |
795 | ||
796 | void mptcp_data_ready(struct sock *sk, struct sock *ssk) | |
101f6f85 | 797 | { |
6719331c | 798 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); |
101f6f85 | 799 | struct mptcp_sock *msk = mptcp_sk(sk); |
13c7ba0c | 800 | int sk_rbuf, ssk_rbuf; |
101f6f85 | 801 | |
d7b1bfd0 PA |
802 | /* The peer can send data while we are shutting down this |
803 | * subflow at msk destruction time, but we must avoid enqueuing | |
804 | * more data to the msk receive queue | |
805 | */ | |
806 | if (unlikely(subflow->disposable)) | |
807 | return; | |
808 | ||
13c7ba0c FW |
809 | ssk_rbuf = READ_ONCE(ssk->sk_rcvbuf); |
810 | sk_rbuf = READ_ONCE(sk->sk_rcvbuf); | |
811 | if (unlikely(ssk_rbuf > sk_rbuf)) | |
812 | sk_rbuf = ssk_rbuf; | |
813 | ||
99d1055c | 814 | /* over limit? can't append more skbs to msk, Also, no need to wake-up*/ |
ce599c51 PA |
815 | if (__mptcp_rmem(sk) > sk_rbuf) { |
816 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RCVPRUNED); | |
99d1055c | 817 | return; |
ce599c51 | 818 | } |
600911ff | 819 | |
99d1055c PA |
820 | /* Wake-up the reader only for in-sequence data */ |
821 | mptcp_data_lock(sk); | |
612f71d7 | 822 | if (move_skbs_to_msk(msk, ssk)) |
6719331c | 823 | sk->sk_data_ready(sk); |
612f71d7 | 824 | |
99d1055c | 825 | mptcp_data_unlock(sk); |
101f6f85 FW |
826 | } |
827 | ||
3e501490 | 828 | static bool __mptcp_finish_join(struct mptcp_sock *msk, struct sock *ssk) |
ec3edaa7 | 829 | { |
3e501490 | 830 | struct sock *sk = (struct sock *)msk; |
5cf92bba | 831 | |
3e501490 | 832 | if (sk->sk_state != TCP_ESTABLISHED) |
78962489 | 833 | return false; |
ec3edaa7 | 834 | |
3e501490 PA |
835 | /* attach to msk socket only after we are sure we will deal with it |
836 | * at close time | |
837 | */ | |
838 | if (sk->sk_socket && !ssk->sk_socket) | |
839 | mptcp_sock_graft(ssk, sk->sk_socket); | |
78962489 | 840 | |
3e501490 PA |
841 | mptcp_sockopt_sync_locked(msk, ssk); |
842 | return true; | |
78962489 FW |
843 | } |
844 | ||
3e501490 | 845 | static void __mptcp_flush_join_list(struct sock *sk) |
78962489 | 846 | { |
3e501490 PA |
847 | struct mptcp_subflow_context *tmp, *subflow; |
848 | struct mptcp_sock *msk = mptcp_sk(sk); | |
78962489 | 849 | |
3e501490 PA |
850 | list_for_each_entry_safe(subflow, tmp, &msk->join_list, node) { |
851 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); | |
852 | bool slow = lock_sock_fast(ssk); | |
78962489 | 853 | |
3e501490 PA |
854 | list_move_tail(&subflow->node, &msk->conn_list); |
855 | if (!__mptcp_finish_join(msk, ssk)) | |
856 | mptcp_subflow_reset(ssk); | |
857 | unlock_sock_fast(ssk, slow); | |
858 | } | |
ec3edaa7 PK |
859 | } |
860 | ||
b51f9b80 PA |
861 | static bool mptcp_timer_pending(struct sock *sk) |
862 | { | |
863 | return timer_pending(&inet_csk(sk)->icsk_retransmit_timer); | |
864 | } | |
865 | ||
866 | static void mptcp_reset_timer(struct sock *sk) | |
867 | { | |
868 | struct inet_connection_sock *icsk = inet_csk(sk); | |
869 | unsigned long tout; | |
870 | ||
e16163b6 PA |
871 | /* prevent rescheduling on close */ |
872 | if (unlikely(inet_sk_state_load(sk) == TCP_CLOSE)) | |
873 | return; | |
874 | ||
33d41c9c | 875 | tout = mptcp_sk(sk)->timer_ival; |
b51f9b80 PA |
876 | sk_reset_timer(sk, &icsk->icsk_retransmit_timer, jiffies + tout); |
877 | } | |
878 | ||
ba8f48f7 PA |
879 | bool mptcp_schedule_work(struct sock *sk) |
880 | { | |
881 | if (inet_sk_state_load(sk) != TCP_CLOSE && | |
882 | schedule_work(&mptcp_sk(sk)->work)) { | |
883 | /* each subflow already holds a reference to the sk, and the | |
884 | * workqueue is invoked by a subflow, so sk can't go away here. | |
885 | */ | |
886 | sock_hold(sk); | |
887 | return true; | |
888 | } | |
889 | return false; | |
890 | } | |
891 | ||
59832e24 FW |
892 | void mptcp_subflow_eof(struct sock *sk) |
893 | { | |
ba8f48f7 PA |
894 | if (!test_and_set_bit(MPTCP_WORK_EOF, &mptcp_sk(sk)->flags)) |
895 | mptcp_schedule_work(sk); | |
59832e24 FW |
896 | } |
897 | ||
5969856a PA |
898 | static void mptcp_check_for_eof(struct mptcp_sock *msk) |
899 | { | |
900 | struct mptcp_subflow_context *subflow; | |
901 | struct sock *sk = (struct sock *)msk; | |
902 | int receivers = 0; | |
903 | ||
904 | mptcp_for_each_subflow(msk, subflow) | |
905 | receivers += !subflow->rx_eof; | |
e16163b6 PA |
906 | if (receivers) |
907 | return; | |
5969856a | 908 | |
e16163b6 | 909 | if (!(sk->sk_shutdown & RCV_SHUTDOWN)) { |
5969856a PA |
910 | /* hopefully temporary hack: propagate shutdown status |
911 | * to msk, when all subflows agree on it | |
912 | */ | |
913 | sk->sk_shutdown |= RCV_SHUTDOWN; | |
914 | ||
915 | smp_mb__before_atomic(); /* SHUTDOWN must be visible first */ | |
5969856a PA |
916 | sk->sk_data_ready(sk); |
917 | } | |
e16163b6 PA |
918 | |
919 | switch (sk->sk_state) { | |
920 | case TCP_ESTABLISHED: | |
921 | inet_sk_state_store(sk, TCP_CLOSE_WAIT); | |
922 | break; | |
923 | case TCP_FIN_WAIT1: | |
26aa2314 PA |
924 | inet_sk_state_store(sk, TCP_CLOSING); |
925 | break; | |
926 | case TCP_FIN_WAIT2: | |
e16163b6 PA |
927 | inet_sk_state_store(sk, TCP_CLOSE); |
928 | break; | |
929 | default: | |
930 | return; | |
931 | } | |
932 | mptcp_close_wake_up(sk); | |
5969856a PA |
933 | } |
934 | ||
7a6a6cbc PA |
935 | static struct sock *mptcp_subflow_recv_lookup(const struct mptcp_sock *msk) |
936 | { | |
937 | struct mptcp_subflow_context *subflow; | |
7a6a6cbc | 938 | |
109cdeb8 | 939 | msk_owned_by_me(msk); |
7a6a6cbc PA |
940 | |
941 | mptcp_for_each_subflow(msk, subflow) { | |
99d1055c | 942 | if (READ_ONCE(subflow->data_avail)) |
7a6a6cbc PA |
943 | return mptcp_subflow_tcp_sock(subflow); |
944 | } | |
945 | ||
946 | return NULL; | |
947 | } | |
948 | ||
3f8e0aae PA |
949 | static bool mptcp_skb_can_collapse_to(u64 write_seq, |
950 | const struct sk_buff *skb, | |
951 | const struct mptcp_ext *mpext) | |
57040755 PA |
952 | { |
953 | if (!tcp_skb_can_collapse_to(skb)) | |
954 | return false; | |
955 | ||
5a369ca6 PA |
956 | /* can collapse only if MPTCP level sequence is in order and this |
957 | * mapping has not been xmitted yet | |
958 | */ | |
959 | return mpext && mpext->data_seq + mpext->data_len == write_seq && | |
960 | !mpext->frozen; | |
57040755 PA |
961 | } |
962 | ||
29249eac PA |
963 | /* we can append data to the given data frag if: |
964 | * - there is space available in the backing page_frag | |
965 | * - the data frag tail matches the current page_frag free offset | |
966 | * - the data frag end sequence number matches the current write seq | |
967 | */ | |
18b683bf PA |
968 | static bool mptcp_frag_can_collapse_to(const struct mptcp_sock *msk, |
969 | const struct page_frag *pfrag, | |
970 | const struct mptcp_data_frag *df) | |
971 | { | |
972 | return df && pfrag->page == df->page && | |
d9ca1de8 | 973 | pfrag->size - pfrag->offset > 0 && |
29249eac | 974 | pfrag->offset == (df->offset + df->data_len) && |
18b683bf PA |
975 | df->data_seq + df->data_len == msk->write_seq; |
976 | } | |
977 | ||
d027236c PA |
978 | static void dfrag_uncharge(struct sock *sk, int len) |
979 | { | |
980 | sk_mem_uncharge(sk, len); | |
7948f6cc | 981 | sk_wmem_queued_add(sk, -len); |
d027236c PA |
982 | } |
983 | ||
984 | static void dfrag_clear(struct sock *sk, struct mptcp_data_frag *dfrag) | |
18b683bf | 985 | { |
d027236c PA |
986 | int len = dfrag->data_len + dfrag->overhead; |
987 | ||
18b683bf | 988 | list_del(&dfrag->list); |
d027236c | 989 | dfrag_uncharge(sk, len); |
18b683bf PA |
990 | put_page(dfrag->page); |
991 | } | |
992 | ||
6e628cd3 | 993 | static void __mptcp_clean_una(struct sock *sk) |
18b683bf PA |
994 | { |
995 | struct mptcp_sock *msk = mptcp_sk(sk); | |
996 | struct mptcp_data_frag *dtmp, *dfrag; | |
e1ff9e82 DC |
997 | u64 snd_una; |
998 | ||
999 | /* on fallback we just need to ignore snd_una, as this is really | |
1000 | * plain TCP | |
1001 | */ | |
1002 | if (__mptcp_check_fallback(msk)) | |
7439d687 | 1003 | msk->snd_una = READ_ONCE(msk->snd_nxt); |
6f8a612a | 1004 | |
7439d687 | 1005 | snd_una = msk->snd_una; |
18b683bf PA |
1006 | list_for_each_entry_safe(dfrag, dtmp, &msk->rtx_queue, list) { |
1007 | if (after64(dfrag->data_seq + dfrag->data_len, snd_una)) | |
1008 | break; | |
1009 | ||
1e1d9d6f PA |
1010 | if (unlikely(dfrag == msk->first_pending)) { |
1011 | /* in recovery mode can see ack after the current snd head */ | |
1012 | if (WARN_ON_ONCE(!msk->recovery)) | |
1013 | break; | |
1014 | ||
1015 | WRITE_ONCE(msk->first_pending, mptcp_send_next(sk)); | |
1016 | } | |
1017 | ||
d027236c | 1018 | dfrag_clear(sk, dfrag); |
d027236c PA |
1019 | } |
1020 | ||
7948f6cc FW |
1021 | dfrag = mptcp_rtx_head(sk); |
1022 | if (dfrag && after64(snd_una, dfrag->data_seq)) { | |
53eb4c38 PA |
1023 | u64 delta = snd_una - dfrag->data_seq; |
1024 | ||
1e1d9d6f PA |
1025 | /* prevent wrap around in recovery mode */ |
1026 | if (unlikely(delta > dfrag->already_sent)) { | |
1027 | if (WARN_ON_ONCE(!msk->recovery)) | |
1028 | goto out; | |
1029 | if (WARN_ON_ONCE(delta > dfrag->data_len)) | |
1030 | goto out; | |
1031 | dfrag->already_sent += delta - dfrag->already_sent; | |
1032 | } | |
7948f6cc FW |
1033 | |
1034 | dfrag->data_seq += delta; | |
53eb4c38 | 1035 | dfrag->offset += delta; |
7948f6cc | 1036 | dfrag->data_len -= delta; |
d9ca1de8 | 1037 | dfrag->already_sent -= delta; |
7948f6cc FW |
1038 | |
1039 | dfrag_uncharge(sk, delta); | |
7948f6cc FW |
1040 | } |
1041 | ||
1e1d9d6f PA |
1042 | /* all retransmitted data acked, recovery completed */ |
1043 | if (unlikely(msk->recovery) && after64(msk->snd_una, msk->recovery_snd_nxt)) | |
1044 | msk->recovery = false; | |
1045 | ||
53eb4c38 | 1046 | out: |
3241a9c0 FW |
1047 | if (snd_una == READ_ONCE(msk->snd_nxt) && |
1048 | snd_una == READ_ONCE(msk->write_seq)) { | |
33d41c9c | 1049 | if (mptcp_timer_pending(sk) && !mptcp_data_fin_enabled(msk)) |
6e628cd3 PA |
1050 | mptcp_stop_timer(sk); |
1051 | } else { | |
1052 | mptcp_reset_timer(sk); | |
18b683bf PA |
1053 | } |
1054 | } | |
1055 | ||
417789df PA |
1056 | static void __mptcp_clean_una_wakeup(struct sock *sk) |
1057 | { | |
765ff425 PA |
1058 | lockdep_assert_held_once(&sk->sk_lock.slock); |
1059 | ||
417789df PA |
1060 | __mptcp_clean_una(sk); |
1061 | mptcp_write_space(sk); | |
1062 | } | |
1063 | ||
b5941f06 PA |
1064 | static void mptcp_clean_una_wakeup(struct sock *sk) |
1065 | { | |
1066 | mptcp_data_lock(sk); | |
1067 | __mptcp_clean_una_wakeup(sk); | |
1068 | mptcp_data_unlock(sk); | |
1069 | } | |
1070 | ||
724cfd2e | 1071 | static void mptcp_enter_memory_pressure(struct sock *sk) |
18b683bf | 1072 | { |
d9ca1de8 PA |
1073 | struct mptcp_subflow_context *subflow; |
1074 | struct mptcp_sock *msk = mptcp_sk(sk); | |
1075 | bool first = true; | |
1076 | ||
18b683bf | 1077 | sk_stream_moderate_sndbuf(sk); |
d9ca1de8 PA |
1078 | mptcp_for_each_subflow(msk, subflow) { |
1079 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); | |
1080 | ||
1081 | if (first) | |
1082 | tcp_enter_memory_pressure(ssk); | |
1083 | sk_stream_moderate_sndbuf(ssk); | |
1084 | first = false; | |
1085 | } | |
724cfd2e PA |
1086 | } |
1087 | ||
1088 | /* ensure we get enough memory for the frag hdr, beyond some minimal amount of | |
1089 | * data | |
1090 | */ | |
1091 | static bool mptcp_page_frag_refill(struct sock *sk, struct page_frag *pfrag) | |
1092 | { | |
1093 | if (likely(skb_page_frag_refill(32U + sizeof(struct mptcp_data_frag), | |
1094 | pfrag, sk->sk_allocation))) | |
1095 | return true; | |
1096 | ||
1097 | mptcp_enter_memory_pressure(sk); | |
18b683bf PA |
1098 | return false; |
1099 | } | |
1100 | ||
1101 | static struct mptcp_data_frag * | |
1102 | mptcp_carve_data_frag(const struct mptcp_sock *msk, struct page_frag *pfrag, | |
1103 | int orig_offset) | |
1104 | { | |
1105 | int offset = ALIGN(orig_offset, sizeof(long)); | |
1106 | struct mptcp_data_frag *dfrag; | |
1107 | ||
1108 | dfrag = (struct mptcp_data_frag *)(page_to_virt(pfrag->page) + offset); | |
1109 | dfrag->data_len = 0; | |
1110 | dfrag->data_seq = msk->write_seq; | |
1111 | dfrag->overhead = offset - orig_offset + sizeof(struct mptcp_data_frag); | |
1112 | dfrag->offset = offset + sizeof(struct mptcp_data_frag); | |
d9ca1de8 | 1113 | dfrag->already_sent = 0; |
18b683bf PA |
1114 | dfrag->page = pfrag->page; |
1115 | ||
1116 | return dfrag; | |
1117 | } | |
1118 | ||
caf971df PA |
1119 | struct mptcp_sendmsg_info { |
1120 | int mss_now; | |
1121 | int size_goal; | |
d9ca1de8 PA |
1122 | u16 limit; |
1123 | u16 sent; | |
1124 | unsigned int flags; | |
1094c6fe | 1125 | bool data_lock_held; |
caf971df PA |
1126 | }; |
1127 | ||
b713d006 PA |
1128 | static int mptcp_check_allowed_size(const struct mptcp_sock *msk, struct sock *ssk, |
1129 | u64 data_seq, int avail_size) | |
6f8a612a FW |
1130 | { |
1131 | u64 window_end = mptcp_wnd_end(msk); | |
b713d006 | 1132 | u64 mptcp_snd_wnd; |
6f8a612a FW |
1133 | |
1134 | if (__mptcp_check_fallback(msk)) | |
1135 | return avail_size; | |
1136 | ||
b713d006 PA |
1137 | mptcp_snd_wnd = window_end - data_seq; |
1138 | avail_size = min_t(unsigned int, mptcp_snd_wnd, avail_size); | |
6f8a612a | 1139 | |
92be2f52 | 1140 | if (unlikely(tcp_sk(ssk)->snd_wnd < mptcp_snd_wnd)) { |
b713d006 | 1141 | tcp_sk(ssk)->snd_wnd = min_t(u64, U32_MAX, mptcp_snd_wnd); |
92be2f52 PA |
1142 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_SNDWNDSHARED); |
1143 | } | |
6f8a612a FW |
1144 | |
1145 | return avail_size; | |
1146 | } | |
1147 | ||
724cfd2e PA |
1148 | static bool __mptcp_add_ext(struct sk_buff *skb, gfp_t gfp) |
1149 | { | |
1150 | struct skb_ext *mpext = __skb_ext_alloc(gfp); | |
1151 | ||
1152 | if (!mpext) | |
1153 | return false; | |
1154 | __skb_ext_set(skb, SKB_EXT_MPTCP, mpext); | |
1155 | return true; | |
1156 | } | |
1157 | ||
6e628cd3 | 1158 | static struct sk_buff *__mptcp_do_alloc_tx_skb(struct sock *sk, gfp_t gfp) |
724cfd2e PA |
1159 | { |
1160 | struct sk_buff *skb; | |
1161 | ||
6e628cd3 | 1162 | skb = alloc_skb_fclone(MAX_TCP_HEADER, gfp); |
724cfd2e | 1163 | if (likely(skb)) { |
6e628cd3 | 1164 | if (likely(__mptcp_add_ext(skb, gfp))) { |
724cfd2e | 1165 | skb_reserve(skb, MAX_TCP_HEADER); |
a52fe46e | 1166 | skb->ip_summed = CHECKSUM_PARTIAL; |
f70cad10 | 1167 | INIT_LIST_HEAD(&skb->tcp_tsorted_anchor); |
724cfd2e PA |
1168 | return skb; |
1169 | } | |
1170 | __kfree_skb(skb); | |
1171 | } else { | |
1172 | mptcp_enter_memory_pressure(sk); | |
1173 | } | |
1174 | return NULL; | |
1175 | } | |
1176 | ||
f70cad10 | 1177 | static struct sk_buff *__mptcp_alloc_tx_skb(struct sock *sk, struct sock *ssk, gfp_t gfp) |
724cfd2e | 1178 | { |
724cfd2e PA |
1179 | struct sk_buff *skb; |
1180 | ||
6e628cd3 | 1181 | skb = __mptcp_do_alloc_tx_skb(sk, gfp); |
724cfd2e | 1182 | if (!skb) |
f70cad10 | 1183 | return NULL; |
724cfd2e PA |
1184 | |
1185 | if (likely(sk_wmem_schedule(ssk, skb->truesize))) { | |
f70cad10 PA |
1186 | tcp_skb_entail(ssk, skb); |
1187 | return skb; | |
724cfd2e | 1188 | } |
3ef3905a | 1189 | tcp_skb_tsorted_anchor_cleanup(skb); |
724cfd2e | 1190 | kfree_skb(skb); |
f70cad10 | 1191 | return NULL; |
724cfd2e PA |
1192 | } |
1193 | ||
f70cad10 | 1194 | static struct sk_buff *mptcp_alloc_tx_skb(struct sock *sk, struct sock *ssk, bool data_lock_held) |
724cfd2e | 1195 | { |
1094c6fe | 1196 | gfp_t gfp = data_lock_held ? GFP_ATOMIC : sk->sk_allocation; |
724cfd2e | 1197 | |
1094c6fe | 1198 | return __mptcp_alloc_tx_skb(sk, ssk, gfp); |
724cfd2e PA |
1199 | } |
1200 | ||
d0cc2987 GT |
1201 | /* note: this always recompute the csum on the whole skb, even |
1202 | * if we just appended a single frag. More status info needed | |
1203 | */ | |
1204 | static void mptcp_update_data_checksum(struct sk_buff *skb, int added) | |
1205 | { | |
1206 | struct mptcp_ext *mpext = mptcp_get_ext(skb); | |
1207 | __wsum csum = ~csum_unfold(mpext->csum); | |
1208 | int offset = skb->len - added; | |
1209 | ||
1210 | mpext->csum = csum_fold(csum_block_add(csum, skb_checksum(skb, offset, added, 0), offset)); | |
1211 | } | |
1212 | ||
1e39e5a3 GT |
1213 | static void mptcp_update_infinite_map(struct mptcp_sock *msk, |
1214 | struct sock *ssk, | |
1215 | struct mptcp_ext *mpext) | |
1216 | { | |
1217 | if (!mpext) | |
1218 | return; | |
1219 | ||
1220 | mpext->infinite_map = 1; | |
1221 | mpext->data_len = 0; | |
1222 | ||
104125b8 | 1223 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_INFINITEMAPTX); |
1e39e5a3 GT |
1224 | mptcp_subflow_ctx(ssk)->send_infinite_map = 0; |
1225 | pr_fallback(msk); | |
d51991e2 | 1226 | mptcp_do_fallback(ssk); |
1e39e5a3 GT |
1227 | } |
1228 | ||
6d0060f6 | 1229 | static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk, |
d9ca1de8 | 1230 | struct mptcp_data_frag *dfrag, |
caf971df | 1231 | struct mptcp_sendmsg_info *info) |
6d0060f6 | 1232 | { |
d9ca1de8 | 1233 | u64 data_seq = dfrag->data_seq + info->sent; |
f70cad10 | 1234 | int offset = dfrag->offset + info->sent; |
6d0060f6 | 1235 | struct mptcp_sock *msk = mptcp_sk(sk); |
6f8a612a | 1236 | bool zero_window_probe = false; |
6d0060f6 | 1237 | struct mptcp_ext *mpext = NULL; |
f70cad10 PA |
1238 | bool can_coalesce = false; |
1239 | bool reuse_skb = true; | |
1240 | struct sk_buff *skb; | |
1241 | size_t copy; | |
1242 | int i; | |
6d0060f6 | 1243 | |
e4b61351 | 1244 | pr_debug("msk=%p ssk=%p sending dfrag at seq=%llu len=%u already sent=%u", |
d9ca1de8 PA |
1245 | msk, ssk, dfrag->data_seq, dfrag->data_len, info->sent); |
1246 | ||
f70cad10 PA |
1247 | if (WARN_ON_ONCE(info->sent > info->limit || |
1248 | info->limit > dfrag->data_len)) | |
1249 | return 0; | |
1250 | ||
c886d702 PA |
1251 | if (unlikely(!__tcp_can_send(ssk))) |
1252 | return -EAGAIN; | |
1253 | ||
d9ca1de8 PA |
1254 | /* compute send limit */ |
1255 | info->mss_now = tcp_send_mss(ssk, &info->size_goal, info->flags); | |
f70cad10 PA |
1256 | copy = info->size_goal; |
1257 | ||
57040755 | 1258 | skb = tcp_write_queue_tail(ssk); |
f70cad10 | 1259 | if (skb && copy > skb->len) { |
57040755 PA |
1260 | /* Limit the write to the size available in the |
1261 | * current skb, if any, so that we create at most a new skb. | |
1262 | * Explicitly tells TCP internals to avoid collapsing on later | |
1263 | * queue management operation, to avoid breaking the ext <-> | |
1264 | * SSN association set here | |
1265 | */ | |
d9ca1de8 | 1266 | mpext = skb_ext_find(skb, SKB_EXT_MPTCP); |
1094c6fe | 1267 | if (!mptcp_skb_can_collapse_to(data_seq, skb, mpext)) { |
57040755 | 1268 | TCP_SKB_CB(skb)->eor = 1; |
1094c6fe PA |
1269 | goto alloc_skb; |
1270 | } | |
1271 | ||
f70cad10 PA |
1272 | i = skb_shinfo(skb)->nr_frags; |
1273 | can_coalesce = skb_can_coalesce(skb, i, dfrag->page, offset); | |
657b991a | 1274 | if (!can_coalesce && i >= READ_ONCE(sysctl_max_skb_frags)) { |
f70cad10 PA |
1275 | tcp_mark_push(tcp_sk(ssk), skb); |
1276 | goto alloc_skb; | |
15e6ca97 | 1277 | } |
18b683bf | 1278 | |
f70cad10 PA |
1279 | copy -= skb->len; |
1280 | } else { | |
1094c6fe | 1281 | alloc_skb: |
f70cad10 PA |
1282 | skb = mptcp_alloc_tx_skb(sk, ssk, info->data_lock_held); |
1283 | if (!skb) | |
1284 | return -ENOMEM; | |
1285 | ||
1286 | i = skb_shinfo(skb)->nr_frags; | |
1287 | reuse_skb = false; | |
1288 | mpext = skb_ext_find(skb, SKB_EXT_MPTCP); | |
1289 | } | |
1094c6fe | 1290 | |
6f8a612a | 1291 | /* Zero window and all data acked? Probe. */ |
b713d006 | 1292 | copy = mptcp_check_allowed_size(msk, ssk, data_seq, copy); |
f70cad10 | 1293 | if (copy == 0) { |
7439d687 PA |
1294 | u64 snd_una = READ_ONCE(msk->snd_una); |
1295 | ||
f70cad10 | 1296 | if (snd_una != msk->snd_nxt) { |
27728ba8 | 1297 | tcp_remove_empty_skb(ssk); |
6f8a612a | 1298 | return 0; |
f70cad10 PA |
1299 | } |
1300 | ||
6f8a612a | 1301 | zero_window_probe = true; |
7439d687 | 1302 | data_seq = snd_una - 1; |
f70cad10 | 1303 | copy = 1; |
6f8a612a | 1304 | |
f70cad10 PA |
1305 | /* all mptcp-level data is acked, no skbs should be present into the |
1306 | * ssk write queue | |
1307 | */ | |
1308 | WARN_ON_ONCE(reuse_skb); | |
1309 | } | |
d027236c | 1310 | |
f70cad10 PA |
1311 | copy = min_t(size_t, copy, info->limit - info->sent); |
1312 | if (!sk_wmem_schedule(ssk, copy)) { | |
27728ba8 | 1313 | tcp_remove_empty_skb(ssk); |
e2223995 | 1314 | return -ENOMEM; |
35759383 | 1315 | } |
18b683bf | 1316 | |
f70cad10 PA |
1317 | if (can_coalesce) { |
1318 | skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy); | |
1319 | } else { | |
1320 | get_page(dfrag->page); | |
1321 | skb_fill_page_desc(skb, i, dfrag->page, offset, copy); | |
57040755 PA |
1322 | } |
1323 | ||
f70cad10 PA |
1324 | skb->len += copy; |
1325 | skb->data_len += copy; | |
1326 | skb->truesize += copy; | |
1327 | sk_wmem_queued_add(ssk, copy); | |
1328 | sk_mem_charge(ssk, copy); | |
f70cad10 PA |
1329 | WRITE_ONCE(tcp_sk(ssk)->write_seq, tcp_sk(ssk)->write_seq + copy); |
1330 | TCP_SKB_CB(skb)->end_seq += copy; | |
1331 | tcp_skb_pcount_set(skb, 0); | |
1332 | ||
1333 | /* on skb reuse we just need to update the DSS len */ | |
1334 | if (reuse_skb) { | |
1335 | TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_PSH; | |
1336 | mpext->data_len += copy; | |
1337 | WARN_ON_ONCE(zero_window_probe); | |
1338 | goto out; | |
724cfd2e | 1339 | } |
6d0060f6 MM |
1340 | |
1341 | memset(mpext, 0, sizeof(*mpext)); | |
d9ca1de8 | 1342 | mpext->data_seq = data_seq; |
6d0060f6 | 1343 | mpext->subflow_seq = mptcp_subflow_ctx(ssk)->rel_write_seq; |
f70cad10 | 1344 | mpext->data_len = copy; |
6d0060f6 MM |
1345 | mpext->use_map = 1; |
1346 | mpext->dsn64 = 1; | |
1347 | ||
1348 | pr_debug("data_seq=%llu subflow_seq=%u data_len=%u dsn64=%d", | |
1349 | mpext->data_seq, mpext->subflow_seq, mpext->data_len, | |
1350 | mpext->dsn64); | |
1351 | ||
6f8a612a | 1352 | if (zero_window_probe) { |
f70cad10 | 1353 | mptcp_subflow_ctx(ssk)->rel_write_seq += copy; |
6f8a612a | 1354 | mpext->frozen = 1; |
d0cc2987 | 1355 | if (READ_ONCE(msk->csum_enabled)) |
f70cad10 | 1356 | mptcp_update_data_checksum(skb, copy); |
6f8a612a | 1357 | tcp_push_pending_frames(ssk); |
d0cc2987 | 1358 | return 0; |
6f8a612a | 1359 | } |
57040755 | 1360 | out: |
d0cc2987 | 1361 | if (READ_ONCE(msk->csum_enabled)) |
f70cad10 | 1362 | mptcp_update_data_checksum(skb, copy); |
1e39e5a3 GT |
1363 | if (mptcp_subflow_ctx(ssk)->send_infinite_map) |
1364 | mptcp_update_infinite_map(msk, ssk, mpext); | |
0eb4e7ee | 1365 | trace_mptcp_sendmsg_frag(mpext); |
f70cad10 PA |
1366 | mptcp_subflow_ctx(ssk)->rel_write_seq += copy; |
1367 | return copy; | |
6d0060f6 MM |
1368 | } |
1369 | ||
d5f49190 PA |
1370 | #define MPTCP_SEND_BURST_SIZE ((1 << 16) - \ |
1371 | sizeof(struct tcphdr) - \ | |
1372 | MAX_TCP_OPTION_SPACE - \ | |
1373 | sizeof(struct ipv6hdr) - \ | |
1374 | sizeof(struct frag_hdr)) | |
1375 | ||
1376 | struct subflow_send_info { | |
1377 | struct sock *ssk; | |
3ce0852c | 1378 | u64 linger_time; |
d5f49190 PA |
1379 | }; |
1380 | ||
ff5a0b42 PA |
1381 | void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow) |
1382 | { | |
1383 | if (!subflow->stale) | |
1384 | return; | |
1385 | ||
1386 | subflow->stale = 0; | |
fc1b4e3b | 1387 | MPTCP_INC_STATS(sock_net(mptcp_subflow_tcp_sock(subflow)), MPTCP_MIB_SUBFLOWRECOVER); |
ff5a0b42 PA |
1388 | } |
1389 | ||
1390 | bool mptcp_subflow_active(struct mptcp_subflow_context *subflow) | |
1391 | { | |
1392 | if (unlikely(subflow->stale)) { | |
1393 | u32 rcv_tstamp = READ_ONCE(tcp_sk(mptcp_subflow_tcp_sock(subflow))->rcv_tstamp); | |
1394 | ||
1395 | if (subflow->stale_rcv_tstamp == rcv_tstamp) | |
1396 | return false; | |
1397 | ||
1398 | mptcp_subflow_set_active(subflow); | |
1399 | } | |
1400 | return __mptcp_subflow_active(subflow); | |
1401 | } | |
1402 | ||
3ce0852c PA |
1403 | #define SSK_MODE_ACTIVE 0 |
1404 | #define SSK_MODE_BACKUP 1 | |
1405 | #define SSK_MODE_MAX 2 | |
1406 | ||
33d41c9c PA |
1407 | /* implement the mptcp packet scheduler; |
1408 | * returns the subflow that will transmit the next DSS | |
1409 | * additionally updates the rtx timeout | |
1410 | */ | |
5cf92bba | 1411 | static struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk) |
f296234c | 1412 | { |
3ce0852c | 1413 | struct subflow_send_info send_info[SSK_MODE_MAX]; |
f296234c | 1414 | struct mptcp_subflow_context *subflow; |
33d41c9c | 1415 | struct sock *sk = (struct sock *)msk; |
3ce0852c | 1416 | u32 pace, burst, wmem; |
d5f49190 PA |
1417 | int i, nr_active = 0; |
1418 | struct sock *ssk; | |
3ce0852c | 1419 | u64 linger_time; |
33d41c9c | 1420 | long tout = 0; |
f296234c | 1421 | |
109cdeb8 | 1422 | msk_owned_by_me(msk); |
f296234c | 1423 | |
d5f49190 PA |
1424 | if (__mptcp_check_fallback(msk)) { |
1425 | if (!msk->first) | |
f296234c | 1426 | return NULL; |
c886d702 PA |
1427 | return __tcp_can_send(msk->first) && |
1428 | sk_stream_memory_free(msk->first) ? msk->first : NULL; | |
d5f49190 PA |
1429 | } |
1430 | ||
1431 | /* re-use last subflow, if the burst allow that */ | |
1432 | if (msk->last_snd && msk->snd_burst > 0 && | |
1433 | sk_stream_memory_free(msk->last_snd) && | |
33d41c9c PA |
1434 | mptcp_subflow_active(mptcp_subflow_ctx(msk->last_snd))) { |
1435 | mptcp_set_timeout(sk); | |
d5f49190 | 1436 | return msk->last_snd; |
33d41c9c | 1437 | } |
f296234c | 1438 | |
d5f49190 | 1439 | /* pick the subflow with the lower wmem/wspace ratio */ |
3ce0852c | 1440 | for (i = 0; i < SSK_MODE_MAX; ++i) { |
d5f49190 | 1441 | send_info[i].ssk = NULL; |
3ce0852c | 1442 | send_info[i].linger_time = -1; |
d5f49190 | 1443 | } |
3ce0852c | 1444 | |
d5f49190 | 1445 | mptcp_for_each_subflow(msk, subflow) { |
e10a9892 | 1446 | trace_mptcp_subflow_get_send(subflow); |
d5f49190 PA |
1447 | ssk = mptcp_subflow_tcp_sock(subflow); |
1448 | if (!mptcp_subflow_active(subflow)) | |
1449 | continue; | |
1450 | ||
33d41c9c | 1451 | tout = max(tout, mptcp_timeout_from_subflow(subflow)); |
d5f49190 | 1452 | nr_active += !subflow->backup; |
3ce0852c PA |
1453 | pace = subflow->avg_pacing_rate; |
1454 | if (unlikely(!pace)) { | |
1455 | /* init pacing rate from socket */ | |
1456 | subflow->avg_pacing_rate = READ_ONCE(ssk->sk_pacing_rate); | |
1457 | pace = subflow->avg_pacing_rate; | |
1458 | if (!pace) | |
1459 | continue; | |
1460 | } | |
f296234c | 1461 | |
3ce0852c PA |
1462 | linger_time = div_u64((u64)READ_ONCE(ssk->sk_wmem_queued) << 32, pace); |
1463 | if (linger_time < send_info[subflow->backup].linger_time) { | |
d5f49190 | 1464 | send_info[subflow->backup].ssk = ssk; |
3ce0852c | 1465 | send_info[subflow->backup].linger_time = linger_time; |
d5f49190 | 1466 | } |
f296234c | 1467 | } |
33d41c9c | 1468 | __mptcp_set_timeout(sk, tout); |
f296234c | 1469 | |
d5f49190 PA |
1470 | /* pick the best backup if no other subflow is active */ |
1471 | if (!nr_active) | |
3ce0852c PA |
1472 | send_info[SSK_MODE_ACTIVE].ssk = send_info[SSK_MODE_BACKUP].ssk; |
1473 | ||
1474 | /* According to the blest algorithm, to avoid HoL blocking for the | |
1475 | * faster flow, we need to: | |
1476 | * - estimate the faster flow linger time | |
1477 | * - use the above to estimate the amount of byte transferred | |
1478 | * by the faster flow | |
1479 | * - check that the amount of queued data is greter than the above, | |
1480 | * otherwise do not use the picked, slower, subflow | |
1481 | * We select the subflow with the shorter estimated time to flush | |
1482 | * the queued mem, which basically ensure the above. We just need | |
1483 | * to check that subflow has a non empty cwin. | |
1484 | */ | |
1485 | ssk = send_info[SSK_MODE_ACTIVE].ssk; | |
b713d006 | 1486 | if (!ssk || !sk_stream_memory_free(ssk)) |
3ce0852c | 1487 | return NULL; |
5cf92bba | 1488 | |
b713d006 | 1489 | burst = min_t(int, MPTCP_SEND_BURST_SIZE, mptcp_wnd_end(msk) - msk->snd_nxt); |
3ce0852c | 1490 | wmem = READ_ONCE(ssk->sk_wmem_queued); |
b713d006 PA |
1491 | if (!burst) { |
1492 | msk->last_snd = NULL; | |
1493 | return ssk; | |
1494 | } | |
1495 | ||
3ce0852c PA |
1496 | subflow = mptcp_subflow_ctx(ssk); |
1497 | subflow->avg_pacing_rate = div_u64((u64)subflow->avg_pacing_rate * wmem + | |
1498 | READ_ONCE(ssk->sk_pacing_rate) * burst, | |
1499 | burst + wmem); | |
1500 | msk->last_snd = ssk; | |
1501 | msk->snd_burst = burst; | |
1502 | return ssk; | |
f296234c PK |
1503 | } |
1504 | ||
b8e0def3 | 1505 | static void mptcp_push_release(struct sock *ssk, struct mptcp_sendmsg_info *info) |
d9ca1de8 | 1506 | { |
d9ca1de8 PA |
1507 | tcp_push(ssk, 0, info->mss_now, tcp_sk(ssk)->nonagle, info->size_goal); |
1508 | release_sock(ssk); | |
1509 | } | |
1510 | ||
0d199e43 FW |
1511 | static void mptcp_update_post_push(struct mptcp_sock *msk, |
1512 | struct mptcp_data_frag *dfrag, | |
1513 | u32 sent) | |
1514 | { | |
1515 | u64 snd_nxt_new = dfrag->data_seq; | |
1516 | ||
1517 | dfrag->already_sent += sent; | |
1518 | ||
1519 | msk->snd_burst -= sent; | |
0d199e43 FW |
1520 | |
1521 | snd_nxt_new += dfrag->already_sent; | |
1522 | ||
1523 | /* snd_nxt_new can be smaller than snd_nxt in case mptcp | |
1524 | * is recovering after a failover. In that event, this re-sends | |
1525 | * old segments. | |
1526 | * | |
1527 | * Thus compute snd_nxt_new candidate based on | |
1528 | * the dfrag->data_seq that was sent and the data | |
1529 | * that has been handed to the subflow for transmission | |
1530 | * and skip update in case it was old dfrag. | |
1531 | */ | |
1532 | if (likely(after64(snd_nxt_new, msk->snd_nxt))) | |
1533 | msk->snd_nxt = snd_nxt_new; | |
1534 | } | |
1535 | ||
8b38217a | 1536 | void mptcp_check_and_set_pending(struct sock *sk) |
3241a9c0 | 1537 | { |
e9d09bac PA |
1538 | if (mptcp_send_head(sk)) |
1539 | mptcp_sk(sk)->push_pending |= BIT(MPTCP_PUSH_PENDING); | |
3241a9c0 FW |
1540 | } |
1541 | ||
ff5a0b42 | 1542 | void __mptcp_push_pending(struct sock *sk, unsigned int flags) |
f870fa0b | 1543 | { |
d9ca1de8 | 1544 | struct sock *prev_ssk = NULL, *ssk = NULL; |
f870fa0b | 1545 | struct mptcp_sock *msk = mptcp_sk(sk); |
caf971df | 1546 | struct mptcp_sendmsg_info info = { |
d9ca1de8 | 1547 | .flags = flags, |
caf971df | 1548 | }; |
0522b424 | 1549 | bool do_check_data_fin = false; |
d9ca1de8 | 1550 | struct mptcp_data_frag *dfrag; |
0522b424 | 1551 | int len; |
d9ca1de8 PA |
1552 | |
1553 | while ((dfrag = mptcp_send_head(sk))) { | |
1554 | info.sent = dfrag->already_sent; | |
1555 | info.limit = dfrag->data_len; | |
1556 | len = dfrag->data_len - dfrag->already_sent; | |
1557 | while (len > 0) { | |
1558 | int ret = 0; | |
1559 | ||
1560 | prev_ssk = ssk; | |
5cf92bba | 1561 | ssk = mptcp_subflow_get_send(msk); |
d9ca1de8 | 1562 | |
9758f40e PA |
1563 | /* First check. If the ssk has changed since |
1564 | * the last round, release prev_ssk | |
d9ca1de8 PA |
1565 | */ |
1566 | if (ssk != prev_ssk && prev_ssk) | |
b8e0def3 | 1567 | mptcp_push_release(prev_ssk, &info); |
d9ca1de8 PA |
1568 | if (!ssk) |
1569 | goto out; | |
1570 | ||
9758f40e PA |
1571 | /* Need to lock the new subflow only if different |
1572 | * from the previous one, otherwise we are still | |
1573 | * helding the relevant lock | |
1574 | */ | |
1575 | if (ssk != prev_ssk) | |
d9ca1de8 PA |
1576 | lock_sock(ssk); |
1577 | ||
1578 | ret = mptcp_sendmsg_frag(sk, ssk, dfrag, &info); | |
1579 | if (ret <= 0) { | |
c886d702 PA |
1580 | if (ret == -EAGAIN) |
1581 | continue; | |
b8e0def3 | 1582 | mptcp_push_release(ssk, &info); |
d9ca1de8 PA |
1583 | goto out; |
1584 | } | |
1585 | ||
0522b424 | 1586 | do_check_data_fin = true; |
d9ca1de8 | 1587 | info.sent += ret; |
d9ca1de8 | 1588 | len -= ret; |
0d199e43 FW |
1589 | |
1590 | mptcp_update_post_push(msk, dfrag, ret); | |
d9ca1de8 PA |
1591 | } |
1592 | WRITE_ONCE(msk->first_pending, mptcp_send_next(sk)); | |
1593 | } | |
1594 | ||
1595 | /* at this point we held the socket lock for the last subflow we used */ | |
1596 | if (ssk) | |
b8e0def3 | 1597 | mptcp_push_release(ssk, &info); |
d9ca1de8 PA |
1598 | |
1599 | out: | |
33d41c9c PA |
1600 | /* ensure the rtx timer is running */ |
1601 | if (!mptcp_timer_pending(sk)) | |
1602 | mptcp_reset_timer(sk); | |
0522b424 | 1603 | if (do_check_data_fin) |
d9ca1de8 PA |
1604 | __mptcp_check_send_data_fin(sk); |
1605 | } | |
1606 | ||
73a0052a | 1607 | static void __mptcp_subflow_push_pending(struct sock *sk, struct sock *ssk, bool first) |
6e628cd3 PA |
1608 | { |
1609 | struct mptcp_sock *msk = mptcp_sk(sk); | |
1094c6fe PA |
1610 | struct mptcp_sendmsg_info info = { |
1611 | .data_lock_held = true, | |
1612 | }; | |
6e628cd3 | 1613 | struct mptcp_data_frag *dfrag; |
b19bc294 | 1614 | struct sock *xmit_ssk; |
6e628cd3 PA |
1615 | int len, copied = 0; |
1616 | ||
1617 | info.flags = 0; | |
1618 | while ((dfrag = mptcp_send_head(sk))) { | |
1619 | info.sent = dfrag->already_sent; | |
1620 | info.limit = dfrag->data_len; | |
1621 | len = dfrag->data_len - dfrag->already_sent; | |
1622 | while (len > 0) { | |
1623 | int ret = 0; | |
1624 | ||
73a0052a | 1625 | /* check for a different subflow usage only after |
b19bc294 PA |
1626 | * spooling the first chunk of data |
1627 | */ | |
00df24f1 | 1628 | xmit_ssk = first ? ssk : mptcp_subflow_get_send(msk); |
b19bc294 PA |
1629 | if (!xmit_ssk) |
1630 | goto out; | |
1631 | if (xmit_ssk != ssk) { | |
bcd97734 PA |
1632 | mptcp_subflow_delegate(mptcp_subflow_ctx(xmit_ssk), |
1633 | MPTCP_DELEGATE_SEND); | |
b19bc294 PA |
1634 | goto out; |
1635 | } | |
1636 | ||
6e628cd3 PA |
1637 | ret = mptcp_sendmsg_frag(sk, ssk, dfrag, &info); |
1638 | if (ret <= 0) | |
1639 | goto out; | |
1640 | ||
1641 | info.sent += ret; | |
6e628cd3 PA |
1642 | copied += ret; |
1643 | len -= ret; | |
b19bc294 | 1644 | first = false; |
0d199e43 FW |
1645 | |
1646 | mptcp_update_post_push(msk, dfrag, ret); | |
6e628cd3 PA |
1647 | } |
1648 | WRITE_ONCE(msk->first_pending, mptcp_send_next(sk)); | |
1649 | } | |
1650 | ||
1651 | out: | |
1652 | /* __mptcp_alloc_tx_skb could have released some wmem and we are | |
1653 | * not going to flush it via release_sock() | |
1654 | */ | |
6e628cd3 | 1655 | if (copied) { |
6e628cd3 PA |
1656 | tcp_push(ssk, 0, info.mss_now, tcp_sk(ssk)->nonagle, |
1657 | info.size_goal); | |
d09d818e PA |
1658 | if (!mptcp_timer_pending(sk)) |
1659 | mptcp_reset_timer(sk); | |
1660 | ||
6e628cd3 PA |
1661 | if (msk->snd_data_fin_enable && |
1662 | msk->snd_nxt + 1 == msk->write_seq) | |
1663 | mptcp_schedule_work(sk); | |
1664 | } | |
1665 | } | |
1666 | ||
5cf92bba PA |
1667 | static void mptcp_set_nospace(struct sock *sk) |
1668 | { | |
1669 | /* enable autotune */ | |
1670 | set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); | |
1671 | ||
1672 | /* will be cleared on avail space */ | |
1673 | set_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags); | |
1674 | } | |
1675 | ||
7d803344 PA |
1676 | static int mptcp_disconnect(struct sock *sk, int flags); |
1677 | ||
a2702a07 | 1678 | static int mptcp_sendmsg_fastopen(struct sock *sk, struct msghdr *msg, |
fa9e5746 PA |
1679 | size_t len, int *copied_syn) |
1680 | { | |
1681 | unsigned int saved_flags = msg->msg_flags; | |
1682 | struct mptcp_sock *msk = mptcp_sk(sk); | |
ddb1a072 | 1683 | struct socket *ssock; |
a2702a07 | 1684 | struct sock *ssk; |
fa9e5746 PA |
1685 | int ret; |
1686 | ||
a2702a07 PA |
1687 | /* on flags based fastopen the mptcp is supposed to create the |
1688 | * first subflow right now. Otherwise we are in the defer_connect | |
1689 | * path, and the first subflow must be already present. | |
1690 | * Since the defer_connect flag is cleared after the first succsful | |
1691 | * fastopen attempt, no need to check for additional subflow status. | |
1692 | */ | |
ddb1a072 PA |
1693 | if (msg->msg_flags & MSG_FASTOPEN) { |
1694 | ssock = __mptcp_nmpc_socket(msk); | |
1695 | if (IS_ERR(ssock)) | |
1696 | return PTR_ERR(ssock); | |
1697 | } | |
a2702a07 PA |
1698 | if (!msk->first) |
1699 | return -EINVAL; | |
1700 | ||
1701 | ssk = msk->first; | |
1702 | ||
fa9e5746 PA |
1703 | lock_sock(ssk); |
1704 | msg->msg_flags |= MSG_DONTWAIT; | |
1705 | msk->connect_flags = O_NONBLOCK; | |
7d803344 | 1706 | msk->fastopening = 1; |
fa9e5746 | 1707 | ret = tcp_sendmsg_fastopen(ssk, msg, copied_syn, len, NULL); |
7d803344 | 1708 | msk->fastopening = 0; |
fa9e5746 PA |
1709 | msg->msg_flags = saved_flags; |
1710 | release_sock(ssk); | |
1711 | ||
1712 | /* do the blocking bits of inet_stream_connect outside the ssk socket lock */ | |
1713 | if (ret == -EINPROGRESS && !(msg->msg_flags & MSG_DONTWAIT)) { | |
1714 | ret = __inet_stream_connect(sk->sk_socket, msg->msg_name, | |
1715 | msg->msg_namelen, msg->msg_flags, 1); | |
1716 | ||
1717 | /* Keep the same behaviour of plain TCP: zero the copied bytes in | |
1718 | * case of any error, except timeout or signal | |
1719 | */ | |
1720 | if (ret && ret != -EINPROGRESS && ret != -ERESTARTSYS && ret != -EINTR) | |
1721 | *copied_syn = 0; | |
7d803344 PA |
1722 | } else if (ret && ret != -EINPROGRESS) { |
1723 | mptcp_disconnect(sk, 0); | |
fa9e5746 | 1724 | } |
a2702a07 | 1725 | inet_sk(sk)->defer_connect = 0; |
fa9e5746 PA |
1726 | |
1727 | return ret; | |
1728 | } | |
1729 | ||
d9ca1de8 PA |
1730 | static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) |
1731 | { | |
1732 | struct mptcp_sock *msk = mptcp_sk(sk); | |
17091708 | 1733 | struct page_frag *pfrag; |
6d0060f6 | 1734 | size_t copied = 0; |
caf971df | 1735 | int ret = 0; |
6d0060f6 | 1736 | long timeo; |
f870fa0b | 1737 | |
987858e5 | 1738 | /* silently ignore everything else */ |
1e777f39 | 1739 | msg->msg_flags &= MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_FASTOPEN; |
987858e5 | 1740 | |
6511882c | 1741 | lock_sock(sk); |
1954b860 | 1742 | |
a2702a07 | 1743 | if (unlikely(inet_sk(sk)->defer_connect || msg->msg_flags & MSG_FASTOPEN)) { |
d98a82a6 DS |
1744 | int copied_syn = 0; |
1745 | ||
a2702a07 | 1746 | ret = mptcp_sendmsg_fastopen(sk, msg, len, &copied_syn); |
d98a82a6 | 1747 | copied += copied_syn; |
fa9e5746 | 1748 | if (ret == -EINPROGRESS && copied_syn > 0) |
d98a82a6 | 1749 | goto out; |
fa9e5746 | 1750 | else if (ret) |
69800e51 | 1751 | goto do_error; |
d98a82a6 DS |
1752 | } |
1753 | ||
1954b860 MM |
1754 | timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); |
1755 | ||
1756 | if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) { | |
1757 | ret = sk_stream_wait_connect(sk, &timeo); | |
1758 | if (ret) | |
69800e51 | 1759 | goto do_error; |
1954b860 MM |
1760 | } |
1761 | ||
69800e51 PA |
1762 | ret = -EPIPE; |
1763 | if (unlikely(sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))) | |
1764 | goto do_error; | |
1765 | ||
17091708 | 1766 | pfrag = sk_page_frag(sk); |
18b683bf | 1767 | |
d9ca1de8 | 1768 | while (msg_data_left(msg)) { |
724cfd2e | 1769 | int total_ts, frag_truesize = 0; |
d9ca1de8 | 1770 | struct mptcp_data_frag *dfrag; |
d9ca1de8 PA |
1771 | bool dfrag_collapsed; |
1772 | size_t psize, offset; | |
18b683bf | 1773 | |
d9ca1de8 PA |
1774 | /* reuse tail pfrag, if possible, or carve a new one from the |
1775 | * page allocator | |
1776 | */ | |
1777 | dfrag = mptcp_pending_tail(sk); | |
1778 | dfrag_collapsed = mptcp_frag_can_collapse_to(msk, pfrag, dfrag); | |
1779 | if (!dfrag_collapsed) { | |
6e628cd3 PA |
1780 | if (!sk_stream_memory_free(sk)) |
1781 | goto wait_for_memory; | |
1782 | ||
d9ca1de8 PA |
1783 | if (!mptcp_page_frag_refill(sk, pfrag)) |
1784 | goto wait_for_memory; | |
1785 | ||
1786 | dfrag = mptcp_carve_data_frag(msk, pfrag, pfrag->offset); | |
1787 | frag_truesize = dfrag->overhead; | |
72511aab | 1788 | } |
6d0060f6 | 1789 | |
d9ca1de8 PA |
1790 | /* we do not bound vs wspace, to allow a single packet. |
1791 | * memory accounting will prevent execessive memory usage | |
1792 | * anyway | |
d5f49190 | 1793 | */ |
d9ca1de8 PA |
1794 | offset = dfrag->offset + dfrag->data_len; |
1795 | psize = pfrag->size - offset; | |
1796 | psize = min_t(size_t, psize, msg_data_left(msg)); | |
724cfd2e | 1797 | total_ts = psize + frag_truesize; |
d9ca1de8 | 1798 | |
6511882c | 1799 | if (!sk_wmem_schedule(sk, total_ts)) |
724cfd2e | 1800 | goto wait_for_memory; |
724cfd2e | 1801 | |
d9ca1de8 PA |
1802 | if (copy_page_from_iter(dfrag->page, offset, psize, |
1803 | &msg->msg_iter) != psize) { | |
1804 | ret = -EFAULT; | |
69800e51 | 1805 | goto do_error; |
72511aab FW |
1806 | } |
1807 | ||
d9ca1de8 | 1808 | /* data successfully copied into the write queue */ |
6511882c | 1809 | sk->sk_forward_alloc -= total_ts; |
d9ca1de8 PA |
1810 | copied += psize; |
1811 | dfrag->data_len += psize; | |
1812 | frag_truesize += psize; | |
1813 | pfrag->offset += frag_truesize; | |
1814 | WRITE_ONCE(msk->write_seq, msk->write_seq + psize); | |
1815 | ||
1816 | /* charge data on mptcp pending queue to the msk socket | |
1817 | * Note: we charge such data both to sk and ssk | |
fb529e62 | 1818 | */ |
d9ca1de8 | 1819 | sk_wmem_queued_add(sk, frag_truesize); |
d9ca1de8 PA |
1820 | if (!dfrag_collapsed) { |
1821 | get_page(dfrag->page); | |
1822 | list_add_tail(&dfrag->list, &msk->rtx_queue); | |
1823 | if (!msk->first_pending) | |
1824 | WRITE_ONCE(msk->first_pending, dfrag); | |
fb529e62 | 1825 | } |
e4b61351 | 1826 | pr_debug("msk=%p dfrag at seq=%llu len=%u sent=%u new=%d", msk, |
d9ca1de8 PA |
1827 | dfrag->data_seq, dfrag->data_len, dfrag->already_sent, |
1828 | !dfrag_collapsed); | |
6d0060f6 | 1829 | |
d9ca1de8 | 1830 | continue; |
b51f9b80 | 1831 | |
d9ca1de8 | 1832 | wait_for_memory: |
5cf92bba | 1833 | mptcp_set_nospace(sk); |
c2e6048f | 1834 | __mptcp_push_pending(sk, msg->msg_flags); |
d9ca1de8 PA |
1835 | ret = sk_stream_wait_memory(sk, &timeo); |
1836 | if (ret) | |
69800e51 | 1837 | goto do_error; |
57040755 | 1838 | } |
6d0060f6 | 1839 | |
13e16037 | 1840 | if (copied) |
c2e6048f | 1841 | __mptcp_push_pending(sk, msg->msg_flags); |
d9ca1de8 | 1842 | |
1954b860 | 1843 | out: |
cec37a6e | 1844 | release_sock(sk); |
69800e51 PA |
1845 | return copied; |
1846 | ||
1847 | do_error: | |
1848 | if (copied) | |
1849 | goto out; | |
1850 | ||
1851 | copied = sk_stream_error(sk, msg->msg_flags, ret); | |
1852 | goto out; | |
f870fa0b MM |
1853 | } |
1854 | ||
6771bfd9 FW |
1855 | static int __mptcp_recvmsg_mskq(struct mptcp_sock *msk, |
1856 | struct msghdr *msg, | |
b7f653b2 FW |
1857 | size_t len, int flags, |
1858 | struct scm_timestamping_internal *tss, | |
1859 | int *cmsg_flags) | |
6771bfd9 | 1860 | { |
ca4fb892 | 1861 | struct sk_buff *skb, *tmp; |
6771bfd9 FW |
1862 | int copied = 0; |
1863 | ||
ca4fb892 | 1864 | skb_queue_walk_safe(&msk->receive_queue, skb, tmp) { |
6771bfd9 FW |
1865 | u32 offset = MPTCP_SKB_CB(skb)->offset; |
1866 | u32 data_len = skb->len - offset; | |
1867 | u32 count = min_t(size_t, len - copied, data_len); | |
1868 | int err; | |
1869 | ||
d976092c PA |
1870 | if (!(flags & MSG_TRUNC)) { |
1871 | err = skb_copy_datagram_msg(skb, offset, msg, count); | |
1872 | if (unlikely(err < 0)) { | |
1873 | if (!copied) | |
1874 | return err; | |
1875 | break; | |
1876 | } | |
6771bfd9 FW |
1877 | } |
1878 | ||
b7f653b2 FW |
1879 | if (MPTCP_SKB_CB(skb)->has_rxtstamp) { |
1880 | tcp_update_recv_tstamps(skb, tss); | |
1881 | *cmsg_flags |= MPTCP_CMSG_TS; | |
1882 | } | |
1883 | ||
6771bfd9 FW |
1884 | copied += count; |
1885 | ||
1886 | if (count < data_len) { | |
2c9e7765 | 1887 | if (!(flags & MSG_PEEK)) { |
ca4fb892 | 1888 | MPTCP_SKB_CB(skb)->offset += count; |
2c9e7765 FW |
1889 | MPTCP_SKB_CB(skb)->map_seq += count; |
1890 | } | |
6771bfd9 FW |
1891 | break; |
1892 | } | |
1893 | ||
ca4fb892 YL |
1894 | if (!(flags & MSG_PEEK)) { |
1895 | /* we will bulk release the skb memory later */ | |
1896 | skb->destructor = NULL; | |
ce599c51 | 1897 | WRITE_ONCE(msk->rmem_released, msk->rmem_released + skb->truesize); |
ca4fb892 YL |
1898 | __skb_unlink(skb, &msk->receive_queue); |
1899 | __kfree_skb(skb); | |
1900 | } | |
6771bfd9 FW |
1901 | |
1902 | if (copied >= len) | |
1903 | break; | |
1904 | } | |
1905 | ||
1906 | return copied; | |
1907 | } | |
1908 | ||
a6b118fe FW |
1909 | /* receive buffer autotuning. See tcp_rcv_space_adjust for more information. |
1910 | * | |
1911 | * Only difference: Use highest rtt estimate of the subflows in use. | |
1912 | */ | |
1913 | static void mptcp_rcv_space_adjust(struct mptcp_sock *msk, int copied) | |
1914 | { | |
1915 | struct mptcp_subflow_context *subflow; | |
1916 | struct sock *sk = (struct sock *)msk; | |
1917 | u32 time, advmss = 1; | |
1918 | u64 rtt_us, mstamp; | |
1919 | ||
109cdeb8 | 1920 | msk_owned_by_me(msk); |
a6b118fe FW |
1921 | |
1922 | if (copied <= 0) | |
1923 | return; | |
1924 | ||
1925 | msk->rcvq_space.copied += copied; | |
1926 | ||
1927 | mstamp = div_u64(tcp_clock_ns(), NSEC_PER_USEC); | |
1928 | time = tcp_stamp_us_delta(mstamp, msk->rcvq_space.time); | |
1929 | ||
1930 | rtt_us = msk->rcvq_space.rtt_us; | |
1931 | if (rtt_us && time < (rtt_us >> 3)) | |
1932 | return; | |
1933 | ||
1934 | rtt_us = 0; | |
1935 | mptcp_for_each_subflow(msk, subflow) { | |
1936 | const struct tcp_sock *tp; | |
1937 | u64 sf_rtt_us; | |
1938 | u32 sf_advmss; | |
1939 | ||
1940 | tp = tcp_sk(mptcp_subflow_tcp_sock(subflow)); | |
1941 | ||
1942 | sf_rtt_us = READ_ONCE(tp->rcv_rtt_est.rtt_us); | |
1943 | sf_advmss = READ_ONCE(tp->advmss); | |
1944 | ||
1945 | rtt_us = max(sf_rtt_us, rtt_us); | |
1946 | advmss = max(sf_advmss, advmss); | |
1947 | } | |
1948 | ||
1949 | msk->rcvq_space.rtt_us = rtt_us; | |
1950 | if (time < (rtt_us >> 3) || rtt_us == 0) | |
1951 | return; | |
1952 | ||
1953 | if (msk->rcvq_space.copied <= msk->rcvq_space.space) | |
1954 | goto new_measure; | |
1955 | ||
78047648 | 1956 | if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_moderate_rcvbuf) && |
a6b118fe FW |
1957 | !(sk->sk_userlocks & SOCK_RCVBUF_LOCK)) { |
1958 | int rcvmem, rcvbuf; | |
1959 | u64 rcvwin, grow; | |
1960 | ||
1961 | rcvwin = ((u64)msk->rcvq_space.copied << 1) + 16 * advmss; | |
1962 | ||
1963 | grow = rcvwin * (msk->rcvq_space.copied - msk->rcvq_space.space); | |
1964 | ||
1965 | do_div(grow, msk->rcvq_space.space); | |
1966 | rcvwin += (grow << 1); | |
1967 | ||
1968 | rcvmem = SKB_TRUESIZE(advmss + MAX_TCP_HEADER); | |
1969 | while (tcp_win_from_space(sk, rcvmem) < advmss) | |
1970 | rcvmem += 128; | |
1971 | ||
1972 | do_div(rcvwin, advmss); | |
1973 | rcvbuf = min_t(u64, rcvwin * rcvmem, | |
02739545 | 1974 | READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2])); |
a6b118fe FW |
1975 | |
1976 | if (rcvbuf > sk->sk_rcvbuf) { | |
1977 | u32 window_clamp; | |
1978 | ||
1979 | window_clamp = tcp_win_from_space(sk, rcvbuf); | |
1980 | WRITE_ONCE(sk->sk_rcvbuf, rcvbuf); | |
1981 | ||
1982 | /* Make subflows follow along. If we do not do this, we | |
1983 | * get drops at subflow level if skbs can't be moved to | |
1984 | * the mptcp rx queue fast enough (announced rcv_win can | |
1985 | * exceed ssk->sk_rcvbuf). | |
1986 | */ | |
1987 | mptcp_for_each_subflow(msk, subflow) { | |
1988 | struct sock *ssk; | |
c76c6956 | 1989 | bool slow; |
a6b118fe FW |
1990 | |
1991 | ssk = mptcp_subflow_tcp_sock(subflow); | |
c76c6956 | 1992 | slow = lock_sock_fast(ssk); |
a6b118fe FW |
1993 | WRITE_ONCE(ssk->sk_rcvbuf, rcvbuf); |
1994 | tcp_sk(ssk)->window_clamp = window_clamp; | |
c76c6956 PA |
1995 | tcp_cleanup_rbuf(ssk, 1); |
1996 | unlock_sock_fast(ssk, slow); | |
a6b118fe FW |
1997 | } |
1998 | } | |
1999 | } | |
2000 | ||
2001 | msk->rcvq_space.space = msk->rcvq_space.copied; | |
2002 | new_measure: | |
2003 | msk->rcvq_space.copied = 0; | |
2004 | msk->rcvq_space.time = mstamp; | |
2005 | } | |
2006 | ||
87952603 PA |
2007 | static void __mptcp_update_rmem(struct sock *sk) |
2008 | { | |
2009 | struct mptcp_sock *msk = mptcp_sk(sk); | |
2010 | ||
2011 | if (!msk->rmem_released) | |
2012 | return; | |
2013 | ||
2014 | atomic_sub(msk->rmem_released, &sk->sk_rmem_alloc); | |
6511882c | 2015 | mptcp_rmem_uncharge(sk, msk->rmem_released); |
ce599c51 | 2016 | WRITE_ONCE(msk->rmem_released, 0); |
87952603 PA |
2017 | } |
2018 | ||
2019 | static void __mptcp_splice_receive_queue(struct sock *sk) | |
2020 | { | |
2021 | struct mptcp_sock *msk = mptcp_sk(sk); | |
2022 | ||
2023 | skb_queue_splice_tail_init(&sk->sk_receive_queue, &msk->receive_queue); | |
2024 | } | |
2025 | ||
e3859603 | 2026 | static bool __mptcp_move_skbs(struct mptcp_sock *msk) |
6771bfd9 | 2027 | { |
87952603 | 2028 | struct sock *sk = (struct sock *)msk; |
6771bfd9 | 2029 | unsigned int moved = 0; |
87952603 | 2030 | bool ret, done; |
d5f49190 | 2031 | |
6771bfd9 FW |
2032 | do { |
2033 | struct sock *ssk = mptcp_subflow_recv_lookup(msk); | |
65f49fe7 | 2034 | bool slowpath; |
6771bfd9 | 2035 | |
87952603 PA |
2036 | /* we can have data pending in the subflows only if the msk |
2037 | * receive buffer was full at subflow_data_ready() time, | |
2038 | * that is an unlikely slow path. | |
2039 | */ | |
2040 | if (likely(!ssk)) | |
6771bfd9 FW |
2041 | break; |
2042 | ||
65f49fe7 | 2043 | slowpath = lock_sock_fast(ssk); |
87952603 | 2044 | mptcp_data_lock(sk); |
e3859603 | 2045 | __mptcp_update_rmem(sk); |
6771bfd9 | 2046 | done = __mptcp_move_skbs_from_subflow(msk, ssk, &moved); |
87952603 | 2047 | mptcp_data_unlock(sk); |
499ada50 PA |
2048 | |
2049 | if (unlikely(ssk->sk_err)) | |
2050 | __mptcp_error_report(sk); | |
65f49fe7 | 2051 | unlock_sock_fast(ssk, slowpath); |
6771bfd9 FW |
2052 | } while (!done); |
2053 | ||
87952603 PA |
2054 | /* acquire the data lock only if some input data is pending */ |
2055 | ret = moved > 0; | |
2056 | if (!RB_EMPTY_ROOT(&msk->out_of_order_queue) || | |
2057 | !skb_queue_empty_lockless(&sk->sk_receive_queue)) { | |
2058 | mptcp_data_lock(sk); | |
2059 | __mptcp_update_rmem(sk); | |
2060 | ret |= __mptcp_ofo_queue(msk); | |
2061 | __mptcp_splice_receive_queue(sk); | |
2062 | mptcp_data_unlock(sk); | |
ab174ad8 | 2063 | } |
87952603 PA |
2064 | if (ret) |
2065 | mptcp_check_data_fin((struct sock *)msk); | |
2066 | return !skb_queue_empty(&msk->receive_queue); | |
6771bfd9 FW |
2067 | } |
2068 | ||
2c9e7765 FW |
2069 | static unsigned int mptcp_inq_hint(const struct sock *sk) |
2070 | { | |
2071 | const struct mptcp_sock *msk = mptcp_sk(sk); | |
2072 | const struct sk_buff *skb; | |
2073 | ||
2074 | skb = skb_peek(&msk->receive_queue); | |
2075 | if (skb) { | |
2076 | u64 hint_val = msk->ack_seq - MPTCP_SKB_CB(skb)->map_seq; | |
2077 | ||
2078 | if (hint_val >= INT_MAX) | |
2079 | return INT_MAX; | |
2080 | ||
2081 | return (unsigned int)hint_val; | |
2082 | } | |
2083 | ||
2084 | if (sk->sk_state == TCP_CLOSE || (sk->sk_shutdown & RCV_SHUTDOWN)) | |
2085 | return 1; | |
2086 | ||
2087 | return 0; | |
2088 | } | |
2089 | ||
f870fa0b | 2090 | static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, |
ec095263 | 2091 | int flags, int *addr_len) |
f870fa0b MM |
2092 | { |
2093 | struct mptcp_sock *msk = mptcp_sk(sk); | |
b7f653b2 FW |
2094 | struct scm_timestamping_internal tss; |
2095 | int copied = 0, cmsg_flags = 0; | |
7a6a6cbc PA |
2096 | int target; |
2097 | long timeo; | |
f870fa0b | 2098 | |
cb9d80f4 PA |
2099 | /* MSG_ERRQUEUE is really a no-op till we support IP_RECVERR */ |
2100 | if (unlikely(flags & MSG_ERRQUEUE)) | |
2101 | return inet_recv_error(sk, msg, len, addr_len); | |
2102 | ||
6511882c | 2103 | lock_sock(sk); |
fd897679 PA |
2104 | if (unlikely(sk->sk_state == TCP_LISTEN)) { |
2105 | copied = -ENOTCONN; | |
2106 | goto out_err; | |
2107 | } | |
2108 | ||
ec095263 | 2109 | timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); |
7a6a6cbc PA |
2110 | |
2111 | len = min_t(size_t, len, INT_MAX); | |
2112 | target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); | |
2113 | ||
2c9e7765 FW |
2114 | if (unlikely(msk->recvmsg_inq)) |
2115 | cmsg_flags = MPTCP_CMSG_INQ; | |
2116 | ||
05e3ecea | 2117 | while (copied < len) { |
e3859603 | 2118 | int bytes_read; |
7a6a6cbc | 2119 | |
b7f653b2 | 2120 | bytes_read = __mptcp_recvmsg_mskq(msk, msg, len - copied, flags, &tss, &cmsg_flags); |
6771bfd9 FW |
2121 | if (unlikely(bytes_read < 0)) { |
2122 | if (!copied) | |
2123 | copied = bytes_read; | |
2124 | goto out_err; | |
2125 | } | |
7a6a6cbc | 2126 | |
6771bfd9 | 2127 | copied += bytes_read; |
7a6a6cbc | 2128 | |
ea4ca586 | 2129 | /* be sure to advertise window change */ |
e3859603 PA |
2130 | mptcp_cleanup_rbuf(msk); |
2131 | ||
2132 | if (skb_queue_empty(&msk->receive_queue) && __mptcp_move_skbs(msk)) | |
2133 | continue; | |
ea4ca586 | 2134 | |
7a6a6cbc PA |
2135 | /* only the master socket status is relevant here. The exit |
2136 | * conditions mirror closely tcp_recvmsg() | |
2137 | */ | |
2138 | if (copied >= target) | |
2139 | break; | |
2140 | ||
2141 | if (copied) { | |
2142 | if (sk->sk_err || | |
2143 | sk->sk_state == TCP_CLOSE || | |
2144 | (sk->sk_shutdown & RCV_SHUTDOWN) || | |
2145 | !timeo || | |
2146 | signal_pending(current)) | |
2147 | break; | |
2148 | } else { | |
2149 | if (sk->sk_err) { | |
2150 | copied = sock_error(sk); | |
2151 | break; | |
2152 | } | |
2153 | ||
5969856a PA |
2154 | if (test_and_clear_bit(MPTCP_WORK_EOF, &msk->flags)) |
2155 | mptcp_check_for_eof(msk); | |
2156 | ||
87952603 PA |
2157 | if (sk->sk_shutdown & RCV_SHUTDOWN) { |
2158 | /* race breaker: the shutdown could be after the | |
2159 | * previous receive queue check | |
2160 | */ | |
e3859603 | 2161 | if (__mptcp_move_skbs(msk)) |
87952603 | 2162 | continue; |
7a6a6cbc | 2163 | break; |
87952603 | 2164 | } |
7a6a6cbc PA |
2165 | |
2166 | if (sk->sk_state == TCP_CLOSE) { | |
2167 | copied = -ENOTCONN; | |
2168 | break; | |
2169 | } | |
2170 | ||
2171 | if (!timeo) { | |
2172 | copied = -EAGAIN; | |
2173 | break; | |
2174 | } | |
2175 | ||
2176 | if (signal_pending(current)) { | |
2177 | copied = sock_intr_errno(timeo); | |
2178 | break; | |
2179 | } | |
2180 | } | |
2181 | ||
2182 | pr_debug("block timeout %ld", timeo); | |
612f71d7 | 2183 | sk_wait_data(sk, &timeo, NULL); |
7a6a6cbc | 2184 | } |
3c90e377 | 2185 | |
6771bfd9 | 2186 | out_err: |
b7f653b2 FW |
2187 | if (cmsg_flags && copied >= 0) { |
2188 | if (cmsg_flags & MPTCP_CMSG_TS) | |
2189 | tcp_recv_timestamp(msg, sk, &tss); | |
2c9e7765 FW |
2190 | |
2191 | if (cmsg_flags & MPTCP_CMSG_INQ) { | |
2192 | unsigned int inq = mptcp_inq_hint(sk); | |
2193 | ||
2194 | put_cmsg(msg, SOL_TCP, TCP_CM_INQ, sizeof(inq), &inq); | |
2195 | } | |
b7f653b2 FW |
2196 | } |
2197 | ||
612f71d7 PA |
2198 | pr_debug("msk=%p rx queue empty=%d:%d copied=%d", |
2199 | msk, skb_queue_empty_lockless(&sk->sk_receive_queue), | |
2200 | skb_queue_empty(&msk->receive_queue), copied); | |
ca4fb892 YL |
2201 | if (!(flags & MSG_PEEK)) |
2202 | mptcp_rcv_space_adjust(msk, copied); | |
a6b118fe | 2203 | |
7a6a6cbc | 2204 | release_sock(sk); |
cec37a6e PK |
2205 | return copied; |
2206 | } | |
2207 | ||
b51f9b80 PA |
2208 | static void mptcp_retransmit_timer(struct timer_list *t) |
2209 | { | |
2210 | struct inet_connection_sock *icsk = from_timer(icsk, t, | |
2211 | icsk_retransmit_timer); | |
2212 | struct sock *sk = &icsk->icsk_inet.sk; | |
2d6f5a2b | 2213 | struct mptcp_sock *msk = mptcp_sk(sk); |
b51f9b80 PA |
2214 | |
2215 | bh_lock_sock(sk); | |
2216 | if (!sock_owned_by_user(sk)) { | |
2d6f5a2b PA |
2217 | /* we need a process context to retransmit */ |
2218 | if (!test_and_set_bit(MPTCP_WORK_RTX, &msk->flags)) | |
2219 | mptcp_schedule_work(sk); | |
b51f9b80 PA |
2220 | } else { |
2221 | /* delegate our work to tcp_release_cb() */ | |
e9d09bac | 2222 | __set_bit(MPTCP_RETRANSMIT, &msk->cb_flags); |
b51f9b80 PA |
2223 | } |
2224 | bh_unlock_sock(sk); | |
2225 | sock_put(sk); | |
2226 | } | |
2227 | ||
e16163b6 PA |
2228 | static void mptcp_timeout_timer(struct timer_list *t) |
2229 | { | |
2230 | struct sock *sk = from_timer(sk, t, sk_timer); | |
2231 | ||
2232 | mptcp_schedule_work(sk); | |
b6d69fc8 | 2233 | sock_put(sk); |
e16163b6 PA |
2234 | } |
2235 | ||
3b1d6210 PA |
2236 | /* Find an idle subflow. Return NULL if there is unacked data at tcp |
2237 | * level. | |
2238 | * | |
2239 | * A backup subflow is returned only if that is the only kind available. | |
2240 | */ | |
ff5a0b42 | 2241 | static struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk) |
3b1d6210 | 2242 | { |
71b7dec2 | 2243 | struct sock *backup = NULL, *pick = NULL; |
3b1d6210 | 2244 | struct mptcp_subflow_context *subflow; |
71b7dec2 | 2245 | int min_stale_count = INT_MAX; |
3b1d6210 | 2246 | |
109cdeb8 | 2247 | msk_owned_by_me(msk); |
3b1d6210 | 2248 | |
d5f49190 | 2249 | if (__mptcp_check_fallback(msk)) |
d9ca1de8 | 2250 | return NULL; |
d5f49190 | 2251 | |
3b1d6210 PA |
2252 | mptcp_for_each_subflow(msk, subflow) { |
2253 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); | |
2254 | ||
ff5a0b42 | 2255 | if (!__mptcp_subflow_active(subflow)) |
d5f49190 PA |
2256 | continue; |
2257 | ||
71b7dec2 PA |
2258 | /* still data outstanding at TCP level? skip this */ |
2259 | if (!tcp_rtx_and_write_queues_empty(ssk)) { | |
2260 | mptcp_pm_subflow_chk_stale(msk, ssk); | |
2261 | min_stale_count = min_t(int, min_stale_count, subflow->stale_count); | |
2262 | continue; | |
860975c6 | 2263 | } |
3b1d6210 PA |
2264 | |
2265 | if (subflow->backup) { | |
2266 | if (!backup) | |
2267 | backup = ssk; | |
2268 | continue; | |
2269 | } | |
2270 | ||
71b7dec2 PA |
2271 | if (!pick) |
2272 | pick = ssk; | |
3b1d6210 PA |
2273 | } |
2274 | ||
71b7dec2 PA |
2275 | if (pick) |
2276 | return pick; | |
2277 | ||
2278 | /* use backup only if there are no progresses anywhere */ | |
2279 | return min_stale_count > 1 ? backup : NULL; | |
3b1d6210 PA |
2280 | } |
2281 | ||
17aee05d FW |
2282 | static void mptcp_dispose_initial_subflow(struct mptcp_sock *msk) |
2283 | { | |
2284 | if (msk->subflow) { | |
2285 | iput(SOCK_INODE(msk->subflow)); | |
2286 | msk->subflow = NULL; | |
2287 | } | |
2288 | } | |
2289 | ||
1e1d9d6f PA |
2290 | bool __mptcp_retransmit_pending_data(struct sock *sk) |
2291 | { | |
2292 | struct mptcp_data_frag *cur, *rtx_head; | |
2293 | struct mptcp_sock *msk = mptcp_sk(sk); | |
2294 | ||
00df24f1 | 2295 | if (__mptcp_check_fallback(msk)) |
1e1d9d6f PA |
2296 | return false; |
2297 | ||
2298 | if (tcp_rtx_and_write_queues_empty(sk)) | |
2299 | return false; | |
2300 | ||
2301 | /* the closing socket has some data untransmitted and/or unacked: | |
2302 | * some data in the mptcp rtx queue has not really xmitted yet. | |
2303 | * keep it simple and re-inject the whole mptcp level rtx queue | |
2304 | */ | |
2305 | mptcp_data_lock(sk); | |
2306 | __mptcp_clean_una_wakeup(sk); | |
2307 | rtx_head = mptcp_rtx_head(sk); | |
2308 | if (!rtx_head) { | |
2309 | mptcp_data_unlock(sk); | |
2310 | return false; | |
2311 | } | |
2312 | ||
0d199e43 | 2313 | msk->recovery_snd_nxt = msk->snd_nxt; |
1e1d9d6f PA |
2314 | msk->recovery = true; |
2315 | mptcp_data_unlock(sk); | |
2316 | ||
2317 | msk->first_pending = rtx_head; | |
1e1d9d6f PA |
2318 | msk->snd_burst = 0; |
2319 | ||
2320 | /* be sure to clear the "sent status" on all re-injected fragments */ | |
2321 | list_for_each_entry(cur, &msk->rtx_queue, list) { | |
2322 | if (!cur->already_sent) | |
2323 | break; | |
2324 | cur->already_sent = 0; | |
2325 | } | |
2326 | ||
2327 | return true; | |
2328 | } | |
2329 | ||
b29fcfb5 PA |
2330 | /* flags for __mptcp_close_ssk() */ |
2331 | #define MPTCP_CF_PUSH BIT(1) | |
2332 | #define MPTCP_CF_FASTCLOSE BIT(2) | |
2333 | ||
cec37a6e PK |
2334 | /* subflow sockets can be either outgoing (connect) or incoming |
2335 | * (accept). | |
2336 | * | |
2337 | * Outgoing subflows use in-kernel sockets. | |
2338 | * Incoming subflows do not have their own 'struct socket' allocated, | |
2339 | * so we need to use tcp_close() after detaching them from the mptcp | |
2340 | * parent socket. | |
2341 | */ | |
a141e02e | 2342 | static void __mptcp_close_ssk(struct sock *sk, struct sock *ssk, |
b29fcfb5 PA |
2343 | struct mptcp_subflow_context *subflow, |
2344 | unsigned int flags) | |
cec37a6e | 2345 | { |
e0be4931 | 2346 | struct mptcp_sock *msk = mptcp_sk(sk); |
63740448 PA |
2347 | bool dispose_it, need_push = false; |
2348 | ||
2349 | /* If the first subflow moved to a close state before accept, e.g. due | |
2350 | * to an incoming reset, mptcp either: | |
2351 | * - if either the subflow or the msk are dead, destroy the context | |
2352 | * (the subflow socket is deleted by inet_child_forget) and the msk | |
2353 | * - otherwise do nothing at the moment and take action at accept and/or | |
2354 | * listener shutdown - user-space must be able to accept() the closed | |
2355 | * socket. | |
2356 | */ | |
2357 | if (msk->in_accept_queue && msk->first == ssk) { | |
2358 | if (!sock_flag(sk, SOCK_DEAD) && !sock_flag(ssk, SOCK_DEAD)) | |
2359 | return; | |
2360 | ||
2361 | /* ensure later check in mptcp_worker() will dispose the msk */ | |
2362 | sock_set_flag(sk, SOCK_DEAD); | |
2363 | lock_sock_nested(ssk, SINGLE_DEPTH_NESTING); | |
2364 | mptcp_subflow_drop_ctx(ssk); | |
2365 | goto out_release; | |
2366 | } | |
e0be4931 | 2367 | |
b29fcfb5 PA |
2368 | dispose_it = !msk->subflow || ssk != msk->subflow->sk; |
2369 | if (dispose_it) | |
2370 | list_del(&subflow->node); | |
cec37a6e | 2371 | |
3f8b2667 | 2372 | lock_sock_nested(ssk, SINGLE_DEPTH_NESTING); |
e16163b6 | 2373 | |
d21f8348 PA |
2374 | if (flags & MPTCP_CF_FASTCLOSE) { |
2375 | /* be sure to force the tcp_disconnect() path, | |
2376 | * to generate the egress reset | |
2377 | */ | |
2378 | ssk->sk_lingertime = 0; | |
2379 | sock_set_flag(ssk, SOCK_LINGER); | |
b29fcfb5 | 2380 | subflow->send_fastclose = 1; |
d21f8348 | 2381 | } |
b29fcfb5 PA |
2382 | |
2383 | need_push = (flags & MPTCP_CF_PUSH) && __mptcp_retransmit_pending_data(sk); | |
2384 | if (!dispose_it) { | |
2385 | tcp_disconnect(ssk, 0); | |
2386 | msk->subflow->state = SS_UNCONNECTED; | |
2387 | mptcp_subflow_ctx_reset(subflow); | |
2388 | release_sock(ssk); | |
2389 | ||
2390 | goto out; | |
2391 | } | |
2392 | ||
d7b1bfd0 PA |
2393 | subflow->disposable = 1; |
2394 | ||
e16163b6 PA |
2395 | /* if ssk hit tcp_done(), tcp_cleanup_ulp() cleared the related ops |
2396 | * the ssk has been already destroyed, we just need to release the | |
2397 | * reference owned by msk; | |
2398 | */ | |
2399 | if (!inet_csk(ssk)->icsk_ulp_ops) { | |
b6985b9b | 2400 | WARN_ON_ONCE(!sock_flag(ssk, SOCK_DEAD)); |
e16163b6 | 2401 | kfree_rcu(subflow, rcu); |
cec37a6e | 2402 | } else { |
d7b1bfd0 | 2403 | /* otherwise tcp will dispose of the ssk and subflow ctx */ |
2a6a870e PA |
2404 | if (ssk->sk_state == TCP_LISTEN) { |
2405 | tcp_set_state(ssk, TCP_CLOSE); | |
2406 | mptcp_subflow_queue_clean(sk, ssk); | |
2407 | inet_csk_listen_stop(ssk); | |
f8c9dfbd | 2408 | mptcp_event_pm_listener(ssk, MPTCP_EVENT_LISTENER_CLOSED); |
2a6a870e | 2409 | } |
0a3f4f1f | 2410 | |
e16163b6 PA |
2411 | __tcp_close(ssk, 0); |
2412 | ||
2413 | /* close acquired an extra ref */ | |
2414 | __sock_put(ssk); | |
cec37a6e | 2415 | } |
63740448 PA |
2416 | |
2417 | out_release: | |
e16163b6 | 2418 | release_sock(ssk); |
e16163b6 PA |
2419 | |
2420 | sock_put(ssk); | |
e0be4931 | 2421 | |
c8fe62f0 FW |
2422 | if (ssk == msk->first) |
2423 | msk->first = NULL; | |
2424 | ||
b29fcfb5 PA |
2425 | out: |
2426 | if (ssk == msk->last_snd) | |
2427 | msk->last_snd = NULL; | |
1e1d9d6f PA |
2428 | |
2429 | if (need_push) | |
2430 | __mptcp_push_pending(sk, 0); | |
f870fa0b MM |
2431 | } |
2432 | ||
a141e02e FW |
2433 | void mptcp_close_ssk(struct sock *sk, struct sock *ssk, |
2434 | struct mptcp_subflow_context *subflow) | |
2435 | { | |
b911c97c FW |
2436 | if (sk->sk_state == TCP_ESTABLISHED) |
2437 | mptcp_event(MPTCP_EVENT_SUB_CLOSED, mptcp_sk(sk), ssk, GFP_KERNEL); | |
a88c9e49 PA |
2438 | |
2439 | /* subflow aborted before reaching the fully_established status | |
2440 | * attempt the creation of the next subflow | |
2441 | */ | |
2442 | mptcp_pm_subflow_check_next(mptcp_sk(sk), ssk, subflow); | |
2443 | ||
b29fcfb5 | 2444 | __mptcp_close_ssk(sk, ssk, subflow, MPTCP_CF_PUSH); |
a141e02e FW |
2445 | } |
2446 | ||
dc24f8b4 PA |
2447 | static unsigned int mptcp_sync_mss(struct sock *sk, u32 pmtu) |
2448 | { | |
2449 | return 0; | |
2450 | } | |
2451 | ||
b6985b9b | 2452 | static void __mptcp_close_subflow(struct sock *sk) |
0e4f35d7 PA |
2453 | { |
2454 | struct mptcp_subflow_context *subflow, *tmp; | |
b6985b9b | 2455 | struct mptcp_sock *msk = mptcp_sk(sk); |
0e4f35d7 | 2456 | |
3abc05d9 FW |
2457 | might_sleep(); |
2458 | ||
5efbf6f7 | 2459 | mptcp_for_each_subflow_safe(msk, subflow, tmp) { |
0e4f35d7 PA |
2460 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); |
2461 | ||
2462 | if (inet_sk_state_load(ssk) != TCP_CLOSE) | |
2463 | continue; | |
2464 | ||
40947e13 FW |
2465 | /* 'subflow_data_ready' will re-sched once rx queue is empty */ |
2466 | if (!skb_queue_empty_lockless(&ssk->sk_receive_queue)) | |
2467 | continue; | |
2468 | ||
b6985b9b PA |
2469 | mptcp_close_ssk(sk, ssk, subflow); |
2470 | } | |
2471 | ||
0e4f35d7 PA |
2472 | } |
2473 | ||
63740448 | 2474 | static bool mptcp_should_close(const struct sock *sk) |
e16163b6 PA |
2475 | { |
2476 | s32 delta = tcp_jiffies32 - inet_csk(sk)->icsk_mtup.probe_timestamp; | |
2477 | struct mptcp_subflow_context *subflow; | |
2478 | ||
63740448 | 2479 | if (delta >= TCP_TIMEWAIT_LEN || mptcp_sk(sk)->in_accept_queue) |
e16163b6 PA |
2480 | return true; |
2481 | ||
2482 | /* if all subflows are in closed status don't bother with additional | |
2483 | * timeout | |
2484 | */ | |
2485 | mptcp_for_each_subflow(mptcp_sk(sk), subflow) { | |
2486 | if (inet_sk_state_load(mptcp_subflow_tcp_sock(subflow)) != | |
2487 | TCP_CLOSE) | |
2488 | return false; | |
2489 | } | |
2490 | return true; | |
2491 | } | |
2492 | ||
50c504a2 FW |
2493 | static void mptcp_check_fastclose(struct mptcp_sock *msk) |
2494 | { | |
2495 | struct mptcp_subflow_context *subflow, *tmp; | |
80638684 | 2496 | struct sock *sk = (struct sock *)msk; |
50c504a2 FW |
2497 | |
2498 | if (likely(!READ_ONCE(msk->rcv_fastclose))) | |
2499 | return; | |
2500 | ||
2501 | mptcp_token_destroy(msk); | |
2502 | ||
5efbf6f7 | 2503 | mptcp_for_each_subflow_safe(msk, subflow, tmp) { |
50c504a2 | 2504 | struct sock *tcp_sk = mptcp_subflow_tcp_sock(subflow); |
75e908c3 | 2505 | bool slow; |
50c504a2 | 2506 | |
75e908c3 | 2507 | slow = lock_sock_fast(tcp_sk); |
50c504a2 FW |
2508 | if (tcp_sk->sk_state != TCP_CLOSE) { |
2509 | tcp_send_active_reset(tcp_sk, GFP_ATOMIC); | |
2510 | tcp_set_state(tcp_sk, TCP_CLOSE); | |
2511 | } | |
75e908c3 | 2512 | unlock_sock_fast(tcp_sk, slow); |
50c504a2 FW |
2513 | } |
2514 | ||
69800e51 PA |
2515 | /* Mirror the tcp_reset() error propagation */ |
2516 | switch (sk->sk_state) { | |
2517 | case TCP_SYN_SENT: | |
9ae8e5ad | 2518 | WRITE_ONCE(sk->sk_err, ECONNREFUSED); |
69800e51 PA |
2519 | break; |
2520 | case TCP_CLOSE_WAIT: | |
9ae8e5ad | 2521 | WRITE_ONCE(sk->sk_err, EPIPE); |
69800e51 PA |
2522 | break; |
2523 | case TCP_CLOSE: | |
2524 | return; | |
2525 | default: | |
9ae8e5ad | 2526 | WRITE_ONCE(sk->sk_err, ECONNRESET); |
69800e51 PA |
2527 | } |
2528 | ||
50c504a2 FW |
2529 | inet_sk_state_store(sk, TCP_CLOSE); |
2530 | sk->sk_shutdown = SHUTDOWN_MASK; | |
2531 | smp_mb__before_atomic(); /* SHUTDOWN must be visible first */ | |
50c504a2 FW |
2532 | set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &msk->flags); |
2533 | ||
69800e51 PA |
2534 | /* the calling mptcp_worker will properly destroy the socket */ |
2535 | if (sock_flag(sk, SOCK_DEAD)) | |
2536 | return; | |
2537 | ||
2538 | sk->sk_state_change(sk); | |
2539 | sk_error_report(sk); | |
50c504a2 FW |
2540 | } |
2541 | ||
2948d0a1 | 2542 | static void __mptcp_retrans(struct sock *sk) |
80992017 | 2543 | { |
2948d0a1 | 2544 | struct mptcp_sock *msk = mptcp_sk(sk); |
caf971df | 2545 | struct mptcp_sendmsg_info info = {}; |
3b1d6210 | 2546 | struct mptcp_data_frag *dfrag; |
3b1d6210 | 2547 | size_t copied = 0; |
2948d0a1 PA |
2548 | struct sock *ssk; |
2549 | int ret; | |
3b1d6210 | 2550 | |
b5941f06 | 2551 | mptcp_clean_una_wakeup(sk); |
3241a9c0 FW |
2552 | |
2553 | /* first check ssk: need to kick "stale" logic */ | |
2554 | ssk = mptcp_subflow_get_retrans(msk); | |
3b1d6210 | 2555 | dfrag = mptcp_rtx_head(sk); |
6477dd39 MM |
2556 | if (!dfrag) { |
2557 | if (mptcp_data_fin_enabled(msk)) { | |
2558 | struct inet_connection_sock *icsk = inet_csk(sk); | |
2559 | ||
2560 | icsk->icsk_retransmits++; | |
2561 | mptcp_set_datafin_timeout(sk); | |
2562 | mptcp_send_ack(msk); | |
2563 | ||
2564 | goto reset_timer; | |
2565 | } | |
2566 | ||
3241a9c0 FW |
2567 | if (!mptcp_send_head(sk)) |
2568 | return; | |
2569 | ||
2570 | goto reset_timer; | |
6477dd39 | 2571 | } |
3b1d6210 | 2572 | |
3b1d6210 | 2573 | if (!ssk) |
2948d0a1 | 2574 | goto reset_timer; |
3b1d6210 PA |
2575 | |
2576 | lock_sock(ssk); | |
2577 | ||
d9ca1de8 PA |
2578 | /* limit retransmission to the bytes already sent on some subflows */ |
2579 | info.sent = 0; | |
4e14867d PA |
2580 | info.limit = READ_ONCE(msk->csum_enabled) ? dfrag->data_len : dfrag->already_sent; |
2581 | while (info.sent < info.limit) { | |
d9ca1de8 | 2582 | ret = mptcp_sendmsg_frag(sk, ssk, dfrag, &info); |
6f8a612a | 2583 | if (ret <= 0) |
3b1d6210 PA |
2584 | break; |
2585 | ||
fc518953 | 2586 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RETRANSSEGS); |
3b1d6210 | 2587 | copied += ret; |
d9ca1de8 | 2588 | info.sent += ret; |
3b1d6210 | 2589 | } |
4e14867d PA |
2590 | if (copied) { |
2591 | dfrag->already_sent = max(dfrag->already_sent, info.sent); | |
caf971df PA |
2592 | tcp_push(ssk, 0, info.mss_now, tcp_sk(ssk)->nonagle, |
2593 | info.size_goal); | |
0530020a | 2594 | WRITE_ONCE(msk->allow_infinite_fallback, false); |
4e14867d | 2595 | } |
3b1d6210 | 2596 | |
3b1d6210 PA |
2597 | release_sock(ssk); |
2598 | ||
2948d0a1 | 2599 | reset_timer: |
3241a9c0 FW |
2600 | mptcp_check_and_set_pending(sk); |
2601 | ||
3b1d6210 PA |
2602 | if (!mptcp_timer_pending(sk)) |
2603 | mptcp_reset_timer(sk); | |
2948d0a1 PA |
2604 | } |
2605 | ||
76a13b31 GT |
2606 | /* schedule the timeout timer for the relevant event: either close timeout |
2607 | * or mp_fail timeout. The close timeout takes precedence on the mp_fail one | |
2608 | */ | |
2609 | void mptcp_reset_timeout(struct mptcp_sock *msk, unsigned long fail_tout) | |
2610 | { | |
2611 | struct sock *sk = (struct sock *)msk; | |
2612 | unsigned long timeout, close_timeout; | |
2613 | ||
2614 | if (!fail_tout && !sock_flag(sk, SOCK_DEAD)) | |
2615 | return; | |
2616 | ||
2617 | close_timeout = inet_csk(sk)->icsk_mtup.probe_timestamp - tcp_jiffies32 + jiffies + TCP_TIMEWAIT_LEN; | |
2618 | ||
2619 | /* the close timeout takes precedence on the fail one, and here at least one of | |
2620 | * them is active | |
2621 | */ | |
2622 | timeout = sock_flag(sk, SOCK_DEAD) ? close_timeout : fail_tout; | |
2623 | ||
2624 | sk_reset_timer(sk, &sk->sk_timer, timeout); | |
2625 | } | |
2626 | ||
49fa1919 GT |
2627 | static void mptcp_mp_fail_no_response(struct mptcp_sock *msk) |
2628 | { | |
76a13b31 | 2629 | struct sock *ssk = msk->first; |
49fa1919 GT |
2630 | bool slow; |
2631 | ||
76a13b31 GT |
2632 | if (!ssk) |
2633 | return; | |
49fa1919 | 2634 | |
76a13b31 GT |
2635 | pr_debug("MP_FAIL doesn't respond, reset the subflow"); |
2636 | ||
2637 | slow = lock_sock_fast(ssk); | |
2638 | mptcp_subflow_reset(ssk); | |
2639 | WRITE_ONCE(mptcp_subflow_ctx(ssk)->fail_tout, 0); | |
2640 | unlock_sock_fast(ssk, slow); | |
2641 | ||
2642 | mptcp_reset_timeout(msk, 0); | |
49fa1919 GT |
2643 | } |
2644 | ||
d21f8348 PA |
2645 | static void mptcp_do_fastclose(struct sock *sk) |
2646 | { | |
2647 | struct mptcp_subflow_context *subflow, *tmp; | |
2648 | struct mptcp_sock *msk = mptcp_sk(sk); | |
2649 | ||
2650 | mptcp_for_each_subflow_safe(msk, subflow, tmp) | |
2651 | __mptcp_close_ssk(sk, mptcp_subflow_tcp_sock(subflow), | |
2652 | subflow, MPTCP_CF_FASTCLOSE); | |
2653 | } | |
2654 | ||
2948d0a1 PA |
2655 | static void mptcp_worker(struct work_struct *work) |
2656 | { | |
2657 | struct mptcp_sock *msk = container_of(work, struct mptcp_sock, work); | |
80638684 | 2658 | struct sock *sk = (struct sock *)msk; |
76a13b31 | 2659 | unsigned long fail_tout; |
2948d0a1 PA |
2660 | int state; |
2661 | ||
2662 | lock_sock(sk); | |
2663 | state = sk->sk_state; | |
d6a04437 | 2664 | if (unlikely((1 << state) & (TCPF_CLOSE | TCPF_LISTEN))) |
2948d0a1 PA |
2665 | goto unlock; |
2666 | ||
2667 | mptcp_check_data_fin_ack(sk); | |
2948d0a1 PA |
2668 | |
2669 | mptcp_check_fastclose(msk); | |
2670 | ||
86e39e04 | 2671 | mptcp_pm_nl_work(msk); |
2948d0a1 PA |
2672 | |
2673 | if (test_and_clear_bit(MPTCP_WORK_EOF, &msk->flags)) | |
2674 | mptcp_check_for_eof(msk); | |
2675 | ||
2676 | __mptcp_check_send_data_fin(sk); | |
2677 | mptcp_check_data_fin(sk); | |
2678 | ||
b6985b9b PA |
2679 | if (test_and_clear_bit(MPTCP_WORK_CLOSE_SUBFLOW, &msk->flags)) |
2680 | __mptcp_close_subflow(sk); | |
2681 | ||
2948d0a1 PA |
2682 | /* There is no point in keeping around an orphaned sk timedout or |
2683 | * closed, but we need the msk around to reply to incoming DATA_FIN, | |
2684 | * even if it is orphaned and in FIN_WAIT2 state | |
2685 | */ | |
d21f8348 | 2686 | if (sock_flag(sk, SOCK_DEAD)) { |
63740448 | 2687 | if (mptcp_should_close(sk)) { |
d21f8348 PA |
2688 | inet_sk_state_store(sk, TCP_CLOSE); |
2689 | mptcp_do_fastclose(sk); | |
2690 | } | |
2691 | if (sk->sk_state == TCP_CLOSE) { | |
2692 | __mptcp_destroy_sock(sk); | |
2693 | goto unlock; | |
2694 | } | |
2948d0a1 PA |
2695 | } |
2696 | ||
2948d0a1 PA |
2697 | if (test_and_clear_bit(MPTCP_WORK_RTX, &msk->flags)) |
2698 | __mptcp_retrans(sk); | |
3b1d6210 | 2699 | |
76a13b31 GT |
2700 | fail_tout = msk->first ? READ_ONCE(mptcp_subflow_ctx(msk->first)->fail_tout) : 0; |
2701 | if (fail_tout && time_after(jiffies, fail_tout)) | |
2702 | mptcp_mp_fail_no_response(msk); | |
49fa1919 | 2703 | |
3b1d6210 | 2704 | unlock: |
80992017 PA |
2705 | release_sock(sk); |
2706 | sock_put(sk); | |
2707 | } | |
2708 | ||
784325e9 | 2709 | static int __mptcp_init_sock(struct sock *sk) |
f870fa0b | 2710 | { |
cec37a6e PK |
2711 | struct mptcp_sock *msk = mptcp_sk(sk); |
2712 | ||
2713 | INIT_LIST_HEAD(&msk->conn_list); | |
ec3edaa7 | 2714 | INIT_LIST_HEAD(&msk->join_list); |
18b683bf | 2715 | INIT_LIST_HEAD(&msk->rtx_queue); |
80992017 | 2716 | INIT_WORK(&msk->work, mptcp_worker); |
87952603 | 2717 | __skb_queue_head_init(&msk->receive_queue); |
ab174ad8 | 2718 | msk->out_of_order_queue = RB_ROOT; |
f0e6a4cf | 2719 | msk->first_pending = NULL; |
6511882c | 2720 | msk->rmem_fwd_alloc = 0; |
ce599c51 | 2721 | WRITE_ONCE(msk->rmem_released, 0); |
33d41c9c | 2722 | msk->timer_ival = TCP_RTO_MIN; |
cec37a6e | 2723 | |
8ab183de | 2724 | msk->first = NULL; |
dc24f8b4 | 2725 | inet_csk(sk)->icsk_sync_mss = mptcp_sync_mss; |
752e9067 | 2726 | WRITE_ONCE(msk->csum_enabled, mptcp_is_checksum_enabled(sock_net(sk))); |
0530020a | 2727 | WRITE_ONCE(msk->allow_infinite_fallback, true); |
1e1d9d6f | 2728 | msk->recovery = false; |
8ab183de | 2729 | |
1b1c7a0e PK |
2730 | mptcp_pm_data_init(msk); |
2731 | ||
b51f9b80 PA |
2732 | /* re-use the csk retrans timer for MPTCP-level retrans */ |
2733 | timer_setup(&msk->sk.icsk_retransmit_timer, mptcp_retransmit_timer, 0); | |
e16163b6 | 2734 | timer_setup(&sk->sk_timer, mptcp_timeout_timer, 0); |
aa1fbd94 | 2735 | |
f870fa0b MM |
2736 | return 0; |
2737 | } | |
2738 | ||
b29fcfb5 | 2739 | static void mptcp_ca_reset(struct sock *sk) |
784325e9 | 2740 | { |
20b5759f | 2741 | struct inet_connection_sock *icsk = inet_csk(sk); |
b29fcfb5 PA |
2742 | |
2743 | tcp_assign_congestion_control(sk); | |
2744 | strcpy(mptcp_sk(sk)->ca_name, icsk->icsk_ca_ops->name); | |
2745 | ||
2746 | /* no need to keep a reference to the ops, the name will suffice */ | |
2747 | tcp_cleanup_congestion_control(sk); | |
2748 | icsk->icsk_ca_ops = NULL; | |
2749 | } | |
2750 | ||
2751 | static int mptcp_init_sock(struct sock *sk) | |
2752 | { | |
fc518953 FW |
2753 | struct net *net = sock_net(sk); |
2754 | int ret; | |
18b683bf | 2755 | |
b6c08380 GT |
2756 | ret = __mptcp_init_sock(sk); |
2757 | if (ret) | |
2758 | return ret; | |
2759 | ||
fc518953 FW |
2760 | if (!mptcp_is_enabled(net)) |
2761 | return -ENOPROTOOPT; | |
2762 | ||
2763 | if (unlikely(!net->mib.mptcp_statistics) && !mptcp_mib_alloc(net)) | |
2764 | return -ENOMEM; | |
2765 | ||
a5ef058d PA |
2766 | set_bit(SOCK_CUSTOM_SOCKOPT, &sk->sk_socket->flags); |
2767 | ||
20b5759f PA |
2768 | /* fetch the ca name; do it outside __mptcp_init_sock(), so that clone will |
2769 | * propagate the correct value | |
2770 | */ | |
b29fcfb5 | 2771 | mptcp_ca_reset(sk); |
20b5759f | 2772 | |
d027236c | 2773 | sk_sockets_allocated_inc(sk); |
a963853f GT |
2774 | sk->sk_rcvbuf = READ_ONCE(net->ipv4.sysctl_tcp_rmem[1]); |
2775 | sk->sk_sndbuf = READ_ONCE(net->ipv4.sysctl_tcp_wmem[1]); | |
d027236c | 2776 | |
18b683bf PA |
2777 | return 0; |
2778 | } | |
2779 | ||
2780 | static void __mptcp_clear_xmit(struct sock *sk) | |
2781 | { | |
2782 | struct mptcp_sock *msk = mptcp_sk(sk); | |
2783 | struct mptcp_data_frag *dtmp, *dfrag; | |
2784 | ||
d9ca1de8 | 2785 | WRITE_ONCE(msk->first_pending, NULL); |
18b683bf | 2786 | list_for_each_entry_safe(dfrag, dtmp, &msk->rtx_queue, list) |
d027236c | 2787 | dfrag_clear(sk, dfrag); |
784325e9 MB |
2788 | } |
2789 | ||
30e51b92 | 2790 | void mptcp_cancel_work(struct sock *sk) |
80992017 PA |
2791 | { |
2792 | struct mptcp_sock *msk = mptcp_sk(sk); | |
2793 | ||
b2771d24 | 2794 | if (cancel_work_sync(&msk->work)) |
e16163b6 | 2795 | __sock_put(sk); |
80992017 PA |
2796 | } |
2797 | ||
d0876b22 | 2798 | void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how) |
21498490 PK |
2799 | { |
2800 | lock_sock(ssk); | |
2801 | ||
2802 | switch (ssk->sk_state) { | |
2803 | case TCP_LISTEN: | |
2804 | if (!(how & RCV_SHUTDOWN)) | |
2805 | break; | |
df561f66 | 2806 | fallthrough; |
21498490 PK |
2807 | case TCP_SYN_SENT: |
2808 | tcp_disconnect(ssk, O_NONBLOCK); | |
2809 | break; | |
2810 | default: | |
43b54c6e MM |
2811 | if (__mptcp_check_fallback(mptcp_sk(sk))) { |
2812 | pr_debug("Fallback"); | |
2813 | ssk->sk_shutdown |= how; | |
2814 | tcp_shutdown(ssk, how); | |
2815 | } else { | |
2816 | pr_debug("Sending DATA_FIN on subflow %p", ssk); | |
43b54c6e | 2817 | tcp_send_ack(ssk); |
6477dd39 MM |
2818 | if (!mptcp_timer_pending(sk)) |
2819 | mptcp_reset_timer(sk); | |
43b54c6e | 2820 | } |
21498490 PK |
2821 | break; |
2822 | } | |
2823 | ||
21498490 PK |
2824 | release_sock(ssk); |
2825 | } | |
2826 | ||
6920b851 MM |
2827 | static const unsigned char new_state[16] = { |
2828 | /* current state: new state: action: */ | |
2829 | [0 /* (Invalid) */] = TCP_CLOSE, | |
2830 | [TCP_ESTABLISHED] = TCP_FIN_WAIT1 | TCP_ACTION_FIN, | |
2831 | [TCP_SYN_SENT] = TCP_CLOSE, | |
2832 | [TCP_SYN_RECV] = TCP_FIN_WAIT1 | TCP_ACTION_FIN, | |
2833 | [TCP_FIN_WAIT1] = TCP_FIN_WAIT1, | |
2834 | [TCP_FIN_WAIT2] = TCP_FIN_WAIT2, | |
2835 | [TCP_TIME_WAIT] = TCP_CLOSE, /* should not happen ! */ | |
2836 | [TCP_CLOSE] = TCP_CLOSE, | |
2837 | [TCP_CLOSE_WAIT] = TCP_LAST_ACK | TCP_ACTION_FIN, | |
2838 | [TCP_LAST_ACK] = TCP_LAST_ACK, | |
2839 | [TCP_LISTEN] = TCP_CLOSE, | |
2840 | [TCP_CLOSING] = TCP_CLOSING, | |
2841 | [TCP_NEW_SYN_RECV] = TCP_CLOSE, /* should not happen ! */ | |
2842 | }; | |
2843 | ||
2844 | static int mptcp_close_state(struct sock *sk) | |
2845 | { | |
2846 | int next = (int)new_state[sk->sk_state]; | |
2847 | int ns = next & TCP_STATE_MASK; | |
2848 | ||
2849 | inet_sk_state_store(sk, ns); | |
2850 | ||
2851 | return next & TCP_ACTION_FIN; | |
2852 | } | |
2853 | ||
e16163b6 | 2854 | static void __mptcp_check_send_data_fin(struct sock *sk) |
f870fa0b | 2855 | { |
e16163b6 | 2856 | struct mptcp_subflow_context *subflow; |
f870fa0b MM |
2857 | struct mptcp_sock *msk = mptcp_sk(sk); |
2858 | ||
e16163b6 PA |
2859 | pr_debug("msk=%p snd_data_fin_enable=%d pending=%d snd_nxt=%llu write_seq=%llu", |
2860 | msk, msk->snd_data_fin_enable, !!mptcp_send_head(sk), | |
2861 | msk->snd_nxt, msk->write_seq); | |
43b54c6e | 2862 | |
e16163b6 PA |
2863 | /* we still need to enqueue subflows or not really shutting down, |
2864 | * skip this | |
2865 | */ | |
2866 | if (!msk->snd_data_fin_enable || msk->snd_nxt + 1 != msk->write_seq || | |
2867 | mptcp_send_head(sk)) | |
2868 | return; | |
2869 | ||
2870 | WRITE_ONCE(msk->snd_nxt, msk->write_seq); | |
2871 | ||
26aa2314 PA |
2872 | /* fallback socket will not get data_fin/ack, can move to the next |
2873 | * state now | |
2874 | */ | |
2875 | if (__mptcp_check_fallback(msk)) { | |
58cd405b | 2876 | WRITE_ONCE(msk->snd_una, msk->write_seq); |
26aa2314 PA |
2877 | if ((1 << sk->sk_state) & (TCPF_CLOSING | TCPF_LAST_ACK)) { |
2878 | inet_sk_state_store(sk, TCP_CLOSE); | |
2879 | mptcp_close_wake_up(sk); | |
2880 | } else if (sk->sk_state == TCP_FIN_WAIT1) { | |
2881 | inet_sk_state_store(sk, TCP_FIN_WAIT2); | |
2882 | } | |
43b54c6e MM |
2883 | } |
2884 | ||
e16163b6 PA |
2885 | mptcp_for_each_subflow(msk, subflow) { |
2886 | struct sock *tcp_sk = mptcp_subflow_tcp_sock(subflow); | |
43b54c6e | 2887 | |
e16163b6 | 2888 | mptcp_subflow_shutdown(sk, tcp_sk, SEND_SHUTDOWN); |
43b54c6e | 2889 | } |
e16163b6 | 2890 | } |
2c22c06c | 2891 | |
e16163b6 PA |
2892 | static void __mptcp_wr_shutdown(struct sock *sk) |
2893 | { | |
2894 | struct mptcp_sock *msk = mptcp_sk(sk); | |
43b54c6e | 2895 | |
e16163b6 PA |
2896 | pr_debug("msk=%p snd_data_fin_enable=%d shutdown=%x state=%d pending=%d", |
2897 | msk, msk->snd_data_fin_enable, sk->sk_shutdown, sk->sk_state, | |
2898 | !!mptcp_send_head(sk)); | |
2899 | ||
2900 | /* will be ignored by fallback sockets */ | |
2901 | WRITE_ONCE(msk->write_seq, msk->write_seq + 1); | |
2902 | WRITE_ONCE(msk->snd_data_fin_enable, 1); | |
2903 | ||
2904 | __mptcp_check_send_data_fin(sk); | |
2905 | } | |
2906 | ||
2907 | static void __mptcp_destroy_sock(struct sock *sk) | |
2908 | { | |
e16163b6 | 2909 | struct mptcp_sock *msk = mptcp_sk(sk); |
e16163b6 PA |
2910 | |
2911 | pr_debug("msk=%p", msk); | |
f870fa0b | 2912 | |
3abc05d9 FW |
2913 | might_sleep(); |
2914 | ||
bcf3cf93 | 2915 | mptcp_stop_timer(sk); |
e16163b6 PA |
2916 | sk_stop_timer(sk, &sk->sk_timer); |
2917 | msk->pm.status = 0; | |
b2c5b614 | 2918 | |
e16163b6 | 2919 | sk->sk_prot->destroy(sk); |
80992017 | 2920 | |
6511882c | 2921 | WARN_ON_ONCE(msk->rmem_fwd_alloc); |
87952603 | 2922 | WARN_ON_ONCE(msk->rmem_released); |
e16163b6 PA |
2923 | sk_stream_kill_queues(sk); |
2924 | xfrm_sk_free_policy(sk); | |
aa1fbd94 | 2925 | |
e16163b6 PA |
2926 | sock_put(sk); |
2927 | } | |
2928 | ||
63740448 PA |
2929 | void __mptcp_unaccepted_force_close(struct sock *sk) |
2930 | { | |
2931 | sock_set_flag(sk, SOCK_DEAD); | |
2932 | inet_sk_state_store(sk, TCP_CLOSE); | |
2933 | mptcp_do_fastclose(sk); | |
2934 | __mptcp_destroy_sock(sk); | |
2935 | } | |
2936 | ||
d21f8348 PA |
2937 | static __poll_t mptcp_check_readable(struct mptcp_sock *msk) |
2938 | { | |
2939 | /* Concurrent splices from sk_receive_queue into receive_queue will | |
2940 | * always show at least one non-empty queue when checked in this order. | |
2941 | */ | |
2942 | if (skb_queue_empty_lockless(&((struct sock *)msk)->sk_receive_queue) && | |
2943 | skb_queue_empty_lockless(&msk->receive_queue)) | |
2944 | return 0; | |
2945 | ||
2946 | return EPOLLIN | EPOLLRDNORM; | |
2947 | } | |
2948 | ||
c558246e MD |
2949 | static void mptcp_listen_inuse_dec(struct sock *sk) |
2950 | { | |
2951 | if (inet_sk_state_load(sk) == TCP_LISTEN) | |
2952 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); | |
2953 | } | |
2954 | ||
26d3e21c | 2955 | bool __mptcp_close(struct sock *sk, long timeout) |
e16163b6 PA |
2956 | { |
2957 | struct mptcp_subflow_context *subflow; | |
76a13b31 | 2958 | struct mptcp_sock *msk = mptcp_sk(sk); |
e16163b6 | 2959 | bool do_cancel_work = false; |
d4e85922 | 2960 | int subflows_alive = 0; |
e16163b6 | 2961 | |
e16163b6 PA |
2962 | sk->sk_shutdown = SHUTDOWN_MASK; |
2963 | ||
2964 | if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) { | |
c558246e | 2965 | mptcp_listen_inuse_dec(sk); |
e16163b6 PA |
2966 | inet_sk_state_store(sk, TCP_CLOSE); |
2967 | goto cleanup; | |
2968 | } | |
6771bfd9 | 2969 | |
8d547809 PA |
2970 | if (mptcp_check_readable(msk) || timeout < 0) { |
2971 | /* If the msk has read data, or the caller explicitly ask it, | |
2972 | * do the MPTCP equivalent of TCP reset, aka MPTCP fastclose | |
2973 | */ | |
d21f8348 PA |
2974 | inet_sk_state_store(sk, TCP_CLOSE); |
2975 | mptcp_do_fastclose(sk); | |
8d547809 | 2976 | timeout = 0; |
d21f8348 | 2977 | } else if (mptcp_close_state(sk)) { |
e16163b6 | 2978 | __mptcp_wr_shutdown(sk); |
d21f8348 | 2979 | } |
e16163b6 PA |
2980 | |
2981 | sk_stream_wait_close(sk, timeout); | |
2982 | ||
2983 | cleanup: | |
2984 | /* orphan all the subflows */ | |
2985 | inet_csk(sk)->icsk_mtup.probe_timestamp = tcp_jiffies32; | |
76a13b31 | 2986 | mptcp_for_each_subflow(msk, subflow) { |
e16163b6 | 2987 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); |
49054556 | 2988 | bool slow = lock_sock_fast_nested(ssk); |
e16163b6 | 2989 | |
d4e85922 PA |
2990 | subflows_alive += ssk->sk_state != TCP_CLOSE; |
2991 | ||
76a13b31 GT |
2992 | /* since the close timeout takes precedence on the fail one, |
2993 | * cancel the latter | |
2994 | */ | |
2995 | if (ssk == msk->first) | |
2996 | subflow->fail_tout = 0; | |
2997 | ||
fe948001 MD |
2998 | /* detach from the parent socket, but allow data_ready to |
2999 | * push incoming data into the mptcp stack, to properly ack it | |
3000 | */ | |
3001 | ssk->sk_socket = NULL; | |
3002 | ssk->sk_wq = NULL; | |
e16163b6 | 3003 | unlock_sock_fast(ssk, slow); |
e16163b6 PA |
3004 | } |
3005 | sock_orphan(sk); | |
3006 | ||
d4e85922 PA |
3007 | /* all the subflows are closed, only timeout can change the msk |
3008 | * state, let's not keep resources busy for no reasons | |
3009 | */ | |
3010 | if (subflows_alive == 0) | |
3011 | inet_sk_state_store(sk, TCP_CLOSE); | |
3012 | ||
e16163b6 PA |
3013 | sock_hold(sk); |
3014 | pr_debug("msk=%p state=%d", sk, sk->sk_state); | |
00df24f1 | 3015 | if (msk->token) |
76a13b31 | 3016 | mptcp_event(MPTCP_EVENT_CLOSED, msk, NULL, GFP_KERNEL); |
b29fcfb5 | 3017 | |
e16163b6 PA |
3018 | if (sk->sk_state == TCP_CLOSE) { |
3019 | __mptcp_destroy_sock(sk); | |
3020 | do_cancel_work = true; | |
3021 | } else { | |
76a13b31 | 3022 | mptcp_reset_timeout(msk, 0); |
e16163b6 | 3023 | } |
26d3e21c MD |
3024 | |
3025 | return do_cancel_work; | |
3026 | } | |
3027 | ||
3028 | static void mptcp_close(struct sock *sk, long timeout) | |
3029 | { | |
3030 | bool do_cancel_work; | |
3031 | ||
3032 | lock_sock(sk); | |
3033 | ||
3034 | do_cancel_work = __mptcp_close(sk, timeout); | |
e16163b6 PA |
3035 | release_sock(sk); |
3036 | if (do_cancel_work) | |
3037 | mptcp_cancel_work(sk); | |
b911c97c | 3038 | |
e16163b6 | 3039 | sock_put(sk); |
f870fa0b MM |
3040 | } |
3041 | ||
e72e4032 | 3042 | void mptcp_copy_inaddrs(struct sock *msk, const struct sock *ssk) |
cf7da0d6 PK |
3043 | { |
3044 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
3045 | const struct ipv6_pinfo *ssk6 = inet6_sk(ssk); | |
3046 | struct ipv6_pinfo *msk6 = inet6_sk(msk); | |
3047 | ||
3048 | msk->sk_v6_daddr = ssk->sk_v6_daddr; | |
3049 | msk->sk_v6_rcv_saddr = ssk->sk_v6_rcv_saddr; | |
3050 | ||
3051 | if (msk6 && ssk6) { | |
3052 | msk6->saddr = ssk6->saddr; | |
3053 | msk6->flow_label = ssk6->flow_label; | |
3054 | } | |
3055 | #endif | |
3056 | ||
3057 | inet_sk(msk)->inet_num = inet_sk(ssk)->inet_num; | |
3058 | inet_sk(msk)->inet_dport = inet_sk(ssk)->inet_dport; | |
3059 | inet_sk(msk)->inet_sport = inet_sk(ssk)->inet_sport; | |
3060 | inet_sk(msk)->inet_daddr = inet_sk(ssk)->inet_daddr; | |
3061 | inet_sk(msk)->inet_saddr = inet_sk(ssk)->inet_saddr; | |
3062 | inet_sk(msk)->inet_rcv_saddr = inet_sk(ssk)->inet_rcv_saddr; | |
3063 | } | |
3064 | ||
18b683bf PA |
3065 | static int mptcp_disconnect(struct sock *sk, int flags) |
3066 | { | |
76e2a55d PA |
3067 | struct mptcp_sock *msk = mptcp_sk(sk); |
3068 | ||
7d803344 PA |
3069 | /* We are on the fastopen error path. We can't call straight into the |
3070 | * subflows cleanup code due to lock nesting (we are already under | |
3071 | * msk->firstsocket lock). Do nothing and leave the cleanup to the | |
3072 | * caller. | |
3073 | */ | |
3074 | if (msk->fastopening) | |
3075 | return 0; | |
3076 | ||
c558246e | 3077 | mptcp_listen_inuse_dec(sk); |
b29fcfb5 PA |
3078 | inet_sk_state_store(sk, TCP_CLOSE); |
3079 | ||
bcf3cf93 | 3080 | mptcp_stop_timer(sk); |
b29fcfb5 PA |
3081 | sk_stop_timer(sk, &sk->sk_timer); |
3082 | ||
00df24f1 GT |
3083 | if (msk->token) |
3084 | mptcp_event(MPTCP_EVENT_CLOSED, msk, NULL, GFP_KERNEL); | |
b29fcfb5 | 3085 | |
c0bf3c6a PA |
3086 | /* msk->subflow is still intact, the following will not free the first |
3087 | * subflow | |
3088 | */ | |
3089 | mptcp_destroy_common(msk, MPTCP_CF_FASTCLOSE); | |
b29fcfb5 | 3090 | msk->last_snd = NULL; |
e9d09bac PA |
3091 | WRITE_ONCE(msk->flags, 0); |
3092 | msk->cb_flags = 0; | |
3093 | msk->push_pending = 0; | |
b29fcfb5 PA |
3094 | msk->recovery = false; |
3095 | msk->can_ack = false; | |
3096 | msk->fully_established = false; | |
3097 | msk->rcv_data_fin = false; | |
3098 | msk->snd_data_fin_enable = false; | |
3099 | msk->rcv_fastclose = false; | |
3100 | msk->use_64bit_ack = false; | |
3101 | WRITE_ONCE(msk->csum_enabled, mptcp_is_checksum_enabled(sock_net(sk))); | |
3102 | mptcp_pm_data_reset(msk); | |
3103 | mptcp_ca_reset(sk); | |
3104 | ||
3105 | sk->sk_shutdown = 0; | |
3106 | sk_error_report(sk); | |
42c556fe | 3107 | return 0; |
18b683bf PA |
3108 | } |
3109 | ||
b0519de8 FW |
3110 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
3111 | static struct ipv6_pinfo *mptcp_inet6_sk(const struct sock *sk) | |
3112 | { | |
3113 | unsigned int offset = sizeof(struct mptcp6_sock) - sizeof(struct ipv6_pinfo); | |
3114 | ||
3115 | return (struct ipv6_pinfo *)(((u8 *)sk) + offset); | |
3116 | } | |
3117 | #endif | |
3118 | ||
fca5c82c | 3119 | struct sock *mptcp_sk_clone(const struct sock *sk, |
cfde141e | 3120 | const struct mptcp_options_received *mp_opt, |
fca5c82c | 3121 | struct request_sock *req) |
b0519de8 | 3122 | { |
58b09919 | 3123 | struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req); |
b0519de8 | 3124 | struct sock *nsk = sk_clone_lock(sk, GFP_ATOMIC); |
58b09919 | 3125 | struct mptcp_sock *msk; |
b0519de8 FW |
3126 | |
3127 | if (!nsk) | |
3128 | return NULL; | |
3129 | ||
3130 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
3131 | if (nsk->sk_family == AF_INET6) | |
3132 | inet_sk(nsk)->pinet6 = mptcp_inet6_sk(nsk); | |
3133 | #endif | |
3134 | ||
58b09919 PA |
3135 | __mptcp_init_sock(nsk); |
3136 | ||
3137 | msk = mptcp_sk(nsk); | |
3138 | msk->local_key = subflow_req->local_key; | |
3139 | msk->token = subflow_req->token; | |
3140 | msk->subflow = NULL; | |
b6985b9b | 3141 | msk->in_accept_queue = 1; |
b93df08c | 3142 | WRITE_ONCE(msk->fully_established, false); |
74c7dfbe | 3143 | if (mp_opt->suboptions & OPTION_MPTCP_CSUMREQD) |
06251181 | 3144 | WRITE_ONCE(msk->csum_enabled, true); |
58b09919 | 3145 | |
58b09919 | 3146 | msk->write_seq = subflow_req->idsn + 1; |
eaa2ffab | 3147 | msk->snd_nxt = msk->write_seq; |
7439d687 PA |
3148 | msk->snd_una = msk->write_seq; |
3149 | msk->wnd_end = msk->snd_nxt + req->rsk_rcv_wnd; | |
df00b087 | 3150 | msk->setsockopt_seq = mptcp_sk(sk)->setsockopt_seq; |
6f8a612a | 3151 | |
5e20087d | 3152 | sock_reset_flag(nsk, SOCK_RCU_FREE); |
7f20d5fc PA |
3153 | /* will be fully established after successful MPC subflow creation */ |
3154 | inet_sk_state_store(nsk, TCP_SYN_RECV); | |
0c148460 PA |
3155 | |
3156 | security_inet_csk_clone(nsk, req); | |
58b09919 PA |
3157 | bh_unlock_sock(nsk); |
3158 | ||
b6985b9b | 3159 | /* note: the newly allocated socket refcount is 2 now */ |
b0519de8 FW |
3160 | return nsk; |
3161 | } | |
3162 | ||
a6b118fe FW |
3163 | void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk) |
3164 | { | |
3165 | const struct tcp_sock *tp = tcp_sk(ssk); | |
3166 | ||
3167 | msk->rcvq_space.copied = 0; | |
3168 | msk->rcvq_space.rtt_us = 0; | |
3169 | ||
3170 | msk->rcvq_space.time = tp->tcp_mstamp; | |
3171 | ||
3172 | /* initial rcv_space offering made to peer */ | |
3173 | msk->rcvq_space.space = min_t(u32, tp->rcv_wnd, | |
3174 | TCP_INIT_CWND * tp->advmss); | |
3175 | if (msk->rcvq_space.space == 0) | |
3176 | msk->rcvq_space.space = TCP_INIT_CWND * TCP_MSS_DEFAULT; | |
6f8a612a | 3177 | |
7439d687 | 3178 | WRITE_ONCE(msk->wnd_end, msk->snd_nxt + tcp_sk(ssk)->snd_wnd); |
a6b118fe FW |
3179 | } |
3180 | ||
cf7da0d6 PK |
3181 | static struct sock *mptcp_accept(struct sock *sk, int flags, int *err, |
3182 | bool kern) | |
3183 | { | |
3184 | struct mptcp_sock *msk = mptcp_sk(sk); | |
3185 | struct socket *listener; | |
3186 | struct sock *newsk; | |
3187 | ||
61761231 | 3188 | listener = msk->subflow; |
cf7da0d6 PK |
3189 | if (WARN_ON_ONCE(!listener)) { |
3190 | *err = -EINVAL; | |
3191 | return NULL; | |
3192 | } | |
3193 | ||
3194 | pr_debug("msk=%p, listener=%p", msk, mptcp_subflow_ctx(listener->sk)); | |
3195 | newsk = inet_csk_accept(listener->sk, flags, err, kern); | |
3196 | if (!newsk) | |
3197 | return NULL; | |
3198 | ||
3199 | pr_debug("msk=%p, subflow is mptcp=%d", msk, sk_is_mptcp(newsk)); | |
cf7da0d6 PK |
3200 | if (sk_is_mptcp(newsk)) { |
3201 | struct mptcp_subflow_context *subflow; | |
3202 | struct sock *new_mptcp_sock; | |
cf7da0d6 PK |
3203 | |
3204 | subflow = mptcp_subflow_ctx(newsk); | |
58b09919 | 3205 | new_mptcp_sock = subflow->conn; |
cf7da0d6 | 3206 | |
58b09919 PA |
3207 | /* is_mptcp should be false if subflow->conn is missing, see |
3208 | * subflow_syn_recv_sock() | |
3209 | */ | |
3210 | if (WARN_ON_ONCE(!new_mptcp_sock)) { | |
3211 | tcp_sk(newsk)->is_mptcp = 0; | |
d6692b3b | 3212 | goto out; |
cf7da0d6 PK |
3213 | } |
3214 | ||
cf7da0d6 | 3215 | newsk = new_mptcp_sock; |
0397c6d8 | 3216 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEPASSIVEACK); |
fc518953 FW |
3217 | } else { |
3218 | MPTCP_INC_STATS(sock_net(sk), | |
3219 | MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK); | |
cf7da0d6 PK |
3220 | } |
3221 | ||
d6692b3b FW |
3222 | out: |
3223 | newsk->sk_kern_sock = kern; | |
cf7da0d6 PK |
3224 | return newsk; |
3225 | } | |
3226 | ||
c0bf3c6a | 3227 | void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags) |
5c8c1640 | 3228 | { |
c0bf3c6a | 3229 | struct mptcp_subflow_context *subflow, *tmp; |
87952603 PA |
3230 | struct sock *sk = (struct sock *)msk; |
3231 | ||
6e628cd3 PA |
3232 | __mptcp_clear_xmit(sk); |
3233 | ||
c0bf3c6a | 3234 | /* join list will be eventually flushed (with rst) at sock lock release time */ |
5efbf6f7 | 3235 | mptcp_for_each_subflow_safe(msk, subflow, tmp) |
c0bf3c6a PA |
3236 | __mptcp_close_ssk(sk, mptcp_subflow_tcp_sock(subflow), subflow, flags); |
3237 | ||
87952603 | 3238 | /* move to sk_receive_queue, sk_stream_kill_queues will purge it */ |
b29fcfb5 | 3239 | mptcp_data_lock(sk); |
87952603 | 3240 | skb_queue_splice_tail_init(&msk->receive_queue, &sk->sk_receive_queue); |
6511882c | 3241 | __skb_queue_purge(&sk->sk_receive_queue); |
5c8c1640 | 3242 | skb_rbtree_purge(&msk->out_of_order_queue); |
b29fcfb5 | 3243 | mptcp_data_unlock(sk); |
6511882c PA |
3244 | |
3245 | /* move all the rx fwd alloc into the sk_mem_reclaim_final in | |
3246 | * inet_sock_destruct() will dispose it | |
3247 | */ | |
3248 | sk->sk_forward_alloc += msk->rmem_fwd_alloc; | |
3249 | msk->rmem_fwd_alloc = 0; | |
5c8c1640 GT |
3250 | mptcp_token_destroy(msk); |
3251 | mptcp_pm_free_anno_list(msk); | |
4638de5a | 3252 | mptcp_free_local_addr_list(msk); |
5c8c1640 GT |
3253 | } |
3254 | ||
79c0949e PK |
3255 | static void mptcp_destroy(struct sock *sk) |
3256 | { | |
c9fd9c5f FW |
3257 | struct mptcp_sock *msk = mptcp_sk(sk); |
3258 | ||
c0bf3c6a PA |
3259 | /* clears msk->subflow, allowing the following to close |
3260 | * even the initial subflow | |
3261 | */ | |
3262 | mptcp_dispose_initial_subflow(msk); | |
3263 | mptcp_destroy_common(msk, 0); | |
d027236c | 3264 | sk_sockets_allocated_dec(sk); |
79c0949e PK |
3265 | } |
3266 | ||
6e628cd3 PA |
3267 | void __mptcp_data_acked(struct sock *sk) |
3268 | { | |
3269 | if (!sock_owned_by_user(sk)) | |
3270 | __mptcp_clean_una(sk); | |
3271 | else | |
e9d09bac | 3272 | __set_bit(MPTCP_CLEAN_UNA, &mptcp_sk(sk)->cb_flags); |
6e628cd3 PA |
3273 | |
3274 | if (mptcp_pending_data_fin_ack(sk)) | |
3275 | mptcp_schedule_work(sk); | |
3276 | } | |
3277 | ||
219d0499 | 3278 | void __mptcp_check_push(struct sock *sk, struct sock *ssk) |
6e628cd3 PA |
3279 | { |
3280 | if (!mptcp_send_head(sk)) | |
3281 | return; | |
3282 | ||
73a0052a GT |
3283 | if (!sock_owned_by_user(sk)) |
3284 | __mptcp_subflow_push_pending(sk, ssk, false); | |
3285 | else | |
e9d09bac | 3286 | __set_bit(MPTCP_PUSH_PENDING, &mptcp_sk(sk)->cb_flags); |
6e628cd3 PA |
3287 | } |
3288 | ||
e9d09bac PA |
3289 | #define MPTCP_FLAGS_PROCESS_CTX_NEED (BIT(MPTCP_PUSH_PENDING) | \ |
3290 | BIT(MPTCP_RETRANSMIT) | \ | |
3291 | BIT(MPTCP_FLUSH_JOIN_LIST)) | |
3292 | ||
e93da928 | 3293 | /* processes deferred events and flush wmem */ |
14c441b5 | 3294 | static void mptcp_release_cb(struct sock *sk) |
e9d09bac | 3295 | __must_hold(&sk->sk_lock.slock) |
14c441b5 | 3296 | { |
e9d09bac PA |
3297 | struct mptcp_sock *msk = mptcp_sk(sk); |
3298 | ||
c2e6048f | 3299 | for (;;) { |
e9d09bac PA |
3300 | unsigned long flags = (msk->cb_flags & MPTCP_FLAGS_PROCESS_CTX_NEED) | |
3301 | msk->push_pending; | |
c2e6048f PA |
3302 | if (!flags) |
3303 | break; | |
3304 | ||
3305 | /* the following actions acquire the subflow socket lock | |
6e628cd3 PA |
3306 | * |
3307 | * 1) can't be invoked in atomic scope | |
3308 | * 2) must avoid ABBA deadlock with msk socket spinlock: the RX | |
3309 | * datapath acquires the msk socket spinlock while helding | |
3310 | * the subflow socket lock | |
3311 | */ | |
e9d09bac PA |
3312 | msk->push_pending = 0; |
3313 | msk->cb_flags &= ~flags; | |
6e628cd3 | 3314 | spin_unlock_bh(&sk->sk_lock.slock); |
3e501490 PA |
3315 | if (flags & BIT(MPTCP_FLUSH_JOIN_LIST)) |
3316 | __mptcp_flush_join_list(sk); | |
2e5de7e0 | 3317 | if (flags & BIT(MPTCP_PUSH_PENDING)) |
c2e6048f | 3318 | __mptcp_push_pending(sk, 0); |
2d6f5a2b PA |
3319 | if (flags & BIT(MPTCP_RETRANSMIT)) |
3320 | __mptcp_retrans(sk); | |
c2e6048f PA |
3321 | |
3322 | cond_resched(); | |
6e628cd3 PA |
3323 | spin_lock_bh(&sk->sk_lock.slock); |
3324 | } | |
c2e6048f | 3325 | |
e9d09bac | 3326 | if (__test_and_clear_bit(MPTCP_CLEAN_UNA, &msk->cb_flags)) |
417789df | 3327 | __mptcp_clean_una_wakeup(sk); |
65a569b0 PA |
3328 | if (unlikely(&msk->cb_flags)) { |
3329 | /* be sure to set the current sk state before tacking actions | |
3330 | * depending on sk_state, that is processing MPTCP_ERROR_REPORT | |
3331 | */ | |
3332 | if (__test_and_clear_bit(MPTCP_CONNECTED, &msk->cb_flags)) | |
3333 | __mptcp_set_connected(sk); | |
3334 | if (__test_and_clear_bit(MPTCP_ERROR_REPORT, &msk->cb_flags)) | |
3335 | __mptcp_error_report(sk); | |
43f5b111 PA |
3336 | if (__test_and_clear_bit(MPTCP_RESET_SCHEDULER, &msk->cb_flags)) |
3337 | msk->last_snd = NULL; | |
65a569b0 | 3338 | } |
6e628cd3 | 3339 | |
87952603 | 3340 | __mptcp_update_rmem(sk); |
14c441b5 PA |
3341 | } |
3342 | ||
bcd97734 PA |
3343 | /* MP_JOIN client subflow must wait for 4th ack before sending any data: |
3344 | * TCP can't schedule delack timer before the subflow is fully established. | |
3345 | * MPTCP uses the delack timer to do 3rd ack retransmissions | |
3346 | */ | |
3347 | static void schedule_3rdack_retransmission(struct sock *ssk) | |
3348 | { | |
3349 | struct inet_connection_sock *icsk = inet_csk(ssk); | |
3350 | struct tcp_sock *tp = tcp_sk(ssk); | |
3351 | unsigned long timeout; | |
3352 | ||
3353 | if (mptcp_subflow_ctx(ssk)->fully_established) | |
3354 | return; | |
3355 | ||
3356 | /* reschedule with a timeout above RTT, as we must look only for drop */ | |
3357 | if (tp->srtt_us) | |
3358 | timeout = usecs_to_jiffies(tp->srtt_us >> (3 - 1)); | |
3359 | else | |
3360 | timeout = TCP_TIMEOUT_INIT; | |
3361 | timeout += jiffies; | |
3362 | ||
3363 | WARN_ON_ONCE(icsk->icsk_ack.pending & ICSK_ACK_TIMER); | |
3364 | icsk->icsk_ack.pending |= ICSK_ACK_SCHED | ICSK_ACK_TIMER; | |
3365 | icsk->icsk_ack.timeout = timeout; | |
3366 | sk_reset_timer(ssk, &icsk->icsk_delack_timer, timeout); | |
3367 | } | |
3368 | ||
b19bc294 PA |
3369 | void mptcp_subflow_process_delegated(struct sock *ssk) |
3370 | { | |
3371 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
3372 | struct sock *sk = subflow->conn; | |
3373 | ||
bcd97734 PA |
3374 | if (test_bit(MPTCP_DELEGATE_SEND, &subflow->delegated_status)) { |
3375 | mptcp_data_lock(sk); | |
3376 | if (!sock_owned_by_user(sk)) | |
73a0052a | 3377 | __mptcp_subflow_push_pending(sk, ssk, true); |
bcd97734 | 3378 | else |
e9d09bac | 3379 | __set_bit(MPTCP_PUSH_PENDING, &mptcp_sk(sk)->cb_flags); |
bcd97734 PA |
3380 | mptcp_data_unlock(sk); |
3381 | mptcp_subflow_delegated_done(subflow, MPTCP_DELEGATE_SEND); | |
3382 | } | |
3383 | if (test_bit(MPTCP_DELEGATE_ACK, &subflow->delegated_status)) { | |
3384 | schedule_3rdack_retransmission(ssk); | |
3385 | mptcp_subflow_delegated_done(subflow, MPTCP_DELEGATE_ACK); | |
3386 | } | |
b19bc294 PA |
3387 | } |
3388 | ||
2c5ebd00 PA |
3389 | static int mptcp_hash(struct sock *sk) |
3390 | { | |
3391 | /* should never be called, | |
3392 | * we hash the TCP subflows not the master socket | |
3393 | */ | |
3394 | WARN_ON_ONCE(1); | |
3395 | return 0; | |
3396 | } | |
3397 | ||
3398 | static void mptcp_unhash(struct sock *sk) | |
3399 | { | |
3400 | /* called from sk_common_release(), but nothing to do here */ | |
3401 | } | |
3402 | ||
cec37a6e | 3403 | static int mptcp_get_port(struct sock *sk, unsigned short snum) |
f870fa0b MM |
3404 | { |
3405 | struct mptcp_sock *msk = mptcp_sk(sk); | |
cec37a6e | 3406 | struct socket *ssock; |
f870fa0b | 3407 | |
61761231 | 3408 | ssock = msk->subflow; |
cec37a6e PK |
3409 | pr_debug("msk=%p, subflow=%p", msk, ssock); |
3410 | if (WARN_ON_ONCE(!ssock)) | |
3411 | return -EINVAL; | |
f870fa0b | 3412 | |
cec37a6e PK |
3413 | return inet_csk_get_port(ssock->sk, snum); |
3414 | } | |
f870fa0b | 3415 | |
cec37a6e PK |
3416 | void mptcp_finish_connect(struct sock *ssk) |
3417 | { | |
3418 | struct mptcp_subflow_context *subflow; | |
3419 | struct mptcp_sock *msk; | |
3420 | struct sock *sk; | |
f870fa0b | 3421 | |
cec37a6e | 3422 | subflow = mptcp_subflow_ctx(ssk); |
cec37a6e PK |
3423 | sk = subflow->conn; |
3424 | msk = mptcp_sk(sk); | |
3425 | ||
648ef4b8 MM |
3426 | pr_debug("msk=%p, token=%u", sk, subflow->token); |
3427 | ||
b3ea6b27 | 3428 | subflow->map_seq = subflow->iasn; |
648ef4b8 | 3429 | subflow->map_subflow_seq = 1; |
6d0060f6 | 3430 | |
cec37a6e PK |
3431 | /* the socket is not connected yet, no msk/subflow ops can access/race |
3432 | * accessing the field below | |
3433 | */ | |
cec37a6e | 3434 | WRITE_ONCE(msk->local_key, subflow->local_key); |
6d0060f6 | 3435 | WRITE_ONCE(msk->write_seq, subflow->idsn + 1); |
eaa2ffab | 3436 | WRITE_ONCE(msk->snd_nxt, msk->write_seq); |
7439d687 | 3437 | WRITE_ONCE(msk->snd_una, msk->write_seq); |
1b1c7a0e | 3438 | |
6c714f1b | 3439 | mptcp_pm_new_connection(msk, ssk, 0); |
a6b118fe FW |
3440 | |
3441 | mptcp_rcv_space_init(msk, ssk); | |
f870fa0b MM |
3442 | } |
3443 | ||
866f26f2 | 3444 | void mptcp_sock_graft(struct sock *sk, struct socket *parent) |
cf7da0d6 PK |
3445 | { |
3446 | write_lock_bh(&sk->sk_callback_lock); | |
3447 | rcu_assign_pointer(sk->sk_wq, &parent->wq); | |
3448 | sk_set_socket(sk, parent); | |
3449 | sk->sk_uid = SOCK_INODE(parent)->i_uid; | |
3450 | write_unlock_bh(&sk->sk_callback_lock); | |
3451 | } | |
3452 | ||
e16163b6 | 3453 | bool mptcp_finish_join(struct sock *ssk) |
f296234c | 3454 | { |
e16163b6 | 3455 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); |
f296234c PK |
3456 | struct mptcp_sock *msk = mptcp_sk(subflow->conn); |
3457 | struct sock *parent = (void *)msk; | |
3e501490 | 3458 | bool ret = true; |
f296234c PK |
3459 | |
3460 | pr_debug("msk=%p, subflow=%p", msk, subflow); | |
3461 | ||
3462 | /* mptcp socket already closing? */ | |
dc87efdb FW |
3463 | if (!mptcp_is_fully_established(parent)) { |
3464 | subflow->reset_reason = MPTCP_RST_EMPTCP; | |
f296234c | 3465 | return false; |
dc87efdb | 3466 | } |
f296234c | 3467 | |
70c708e8 | 3468 | if (!list_empty(&subflow->node)) |
b911c97c | 3469 | goto out; |
f296234c | 3470 | |
3e501490 PA |
3471 | if (!mptcp_pm_allow_new_subflow(msk)) |
3472 | goto err_prohibited; | |
10f6d46c | 3473 | |
3e501490 PA |
3474 | /* active connections are already on conn_list. |
3475 | * If we can't acquire msk socket lock here, let the release callback | |
3476 | * handle it | |
10f6d46c | 3477 | */ |
3e501490 PA |
3478 | mptcp_data_lock(parent); |
3479 | if (!sock_owned_by_user(parent)) { | |
3480 | ret = __mptcp_finish_join(msk, ssk); | |
3481 | if (ret) { | |
3482 | sock_hold(ssk); | |
3483 | list_add_tail(&subflow->node, &msk->conn_list); | |
3484 | } | |
3485 | } else { | |
e16163b6 | 3486 | sock_hold(ssk); |
3e501490 | 3487 | list_add_tail(&subflow->node, &msk->join_list); |
e9d09bac | 3488 | __set_bit(MPTCP_FLUSH_JOIN_LIST, &msk->cb_flags); |
e16163b6 | 3489 | } |
3e501490 PA |
3490 | mptcp_data_unlock(parent); |
3491 | ||
dc87efdb | 3492 | if (!ret) { |
3e501490 | 3493 | err_prohibited: |
dc87efdb | 3494 | subflow->reset_reason = MPTCP_RST_EPROHIBIT; |
10f6d46c | 3495 | return false; |
dc87efdb | 3496 | } |
10f6d46c | 3497 | |
917944da | 3498 | subflow->map_seq = READ_ONCE(msk->ack_seq); |
0530020a | 3499 | WRITE_ONCE(msk->allow_infinite_fallback, false); |
3e501490 | 3500 | |
b911c97c FW |
3501 | out: |
3502 | mptcp_event(MPTCP_EVENT_SUB_ESTABLISHED, msk, ssk, GFP_ATOMIC); | |
10f6d46c | 3503 | return true; |
f296234c PK |
3504 | } |
3505 | ||
76e2a55d PA |
3506 | static void mptcp_shutdown(struct sock *sk, int how) |
3507 | { | |
3508 | pr_debug("sk=%p, how=%d", sk, how); | |
3509 | ||
3510 | if ((how & SEND_SHUTDOWN) && mptcp_close_state(sk)) | |
3511 | __mptcp_wr_shutdown(sk); | |
3512 | } | |
3513 | ||
6511882c PA |
3514 | static int mptcp_forward_alloc_get(const struct sock *sk) |
3515 | { | |
3516 | return sk->sk_forward_alloc + mptcp_sk(sk)->rmem_fwd_alloc; | |
3517 | } | |
3518 | ||
644807e3 FW |
3519 | static int mptcp_ioctl_outq(const struct mptcp_sock *msk, u64 v) |
3520 | { | |
3521 | const struct sock *sk = (void *)msk; | |
3522 | u64 delta; | |
3523 | ||
3524 | if (sk->sk_state == TCP_LISTEN) | |
3525 | return -EINVAL; | |
3526 | ||
3527 | if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) | |
3528 | return 0; | |
3529 | ||
3530 | delta = msk->write_seq - v; | |
07c2c7a3 PA |
3531 | if (__mptcp_check_fallback(msk) && msk->first) { |
3532 | struct tcp_sock *tp = tcp_sk(msk->first); | |
3533 | ||
3534 | /* the first subflow is disconnected after close - see | |
3535 | * __mptcp_close_ssk(). tcp_disconnect() moves the write_seq | |
3536 | * so ignore that status, too. | |
3537 | */ | |
3538 | if (!((1 << msk->first->sk_state) & | |
3539 | (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))) | |
3540 | delta += READ_ONCE(tp->write_seq) - tp->snd_una; | |
3541 | } | |
644807e3 FW |
3542 | if (delta > INT_MAX) |
3543 | delta = INT_MAX; | |
3544 | ||
3545 | return (int)delta; | |
3546 | } | |
3547 | ||
3548 | static int mptcp_ioctl(struct sock *sk, int cmd, unsigned long arg) | |
3549 | { | |
3550 | struct mptcp_sock *msk = mptcp_sk(sk); | |
3551 | bool slow; | |
3552 | int answ; | |
3553 | ||
3554 | switch (cmd) { | |
3555 | case SIOCINQ: | |
3556 | if (sk->sk_state == TCP_LISTEN) | |
3557 | return -EINVAL; | |
3558 | ||
3559 | lock_sock(sk); | |
3560 | __mptcp_move_skbs(msk); | |
3561 | answ = mptcp_inq_hint(sk); | |
3562 | release_sock(sk); | |
3563 | break; | |
3564 | case SIOCOUTQ: | |
3565 | slow = lock_sock_fast(sk); | |
3566 | answ = mptcp_ioctl_outq(msk, READ_ONCE(msk->snd_una)); | |
3567 | unlock_sock_fast(sk, slow); | |
3568 | break; | |
3569 | case SIOCOUTQNSD: | |
3570 | slow = lock_sock_fast(sk); | |
3571 | answ = mptcp_ioctl_outq(msk, msk->snd_nxt); | |
3572 | unlock_sock_fast(sk, slow); | |
3573 | break; | |
3574 | default: | |
3575 | return -ENOIOCTLCMD; | |
3576 | } | |
3577 | ||
3578 | return put_user(answ, (int __user *)arg); | |
3579 | } | |
3580 | ||
54f1944e PA |
3581 | static void mptcp_subflow_early_fallback(struct mptcp_sock *msk, |
3582 | struct mptcp_subflow_context *subflow) | |
3583 | { | |
3584 | subflow->request_mptcp = 0; | |
3585 | __mptcp_do_fallback(msk); | |
3586 | } | |
3587 | ||
3588 | static int mptcp_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) | |
3589 | { | |
3590 | struct mptcp_subflow_context *subflow; | |
3591 | struct mptcp_sock *msk = mptcp_sk(sk); | |
3592 | struct socket *ssock; | |
3593 | int err = -EINVAL; | |
3594 | ||
3595 | ssock = __mptcp_nmpc_socket(msk); | |
ddb1a072 PA |
3596 | if (IS_ERR(ssock)) |
3597 | return PTR_ERR(ssock); | |
54f1944e PA |
3598 | |
3599 | mptcp_token_destroy(msk); | |
3600 | inet_sk_state_store(sk, TCP_SYN_SENT); | |
3601 | subflow = mptcp_subflow_ctx(ssock->sk); | |
3602 | #ifdef CONFIG_TCP_MD5SIG | |
3603 | /* no MPTCP if MD5SIG is enabled on this socket or we may run out of | |
3604 | * TCP option space. | |
3605 | */ | |
3606 | if (rcu_access_pointer(tcp_sk(ssock->sk)->md5sig_info)) | |
3607 | mptcp_subflow_early_fallback(msk, subflow); | |
3608 | #endif | |
3609 | if (subflow->request_mptcp && mptcp_token_new_connect(ssock->sk)) { | |
3610 | MPTCP_INC_STATS(sock_net(ssock->sk), MPTCP_MIB_TOKENFALLBACKINIT); | |
3611 | mptcp_subflow_early_fallback(msk, subflow); | |
3612 | } | |
3613 | if (likely(!__mptcp_check_fallback(msk))) | |
3614 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEACTIVE); | |
3615 | ||
3616 | /* if reaching here via the fastopen/sendmsg path, the caller already | |
3617 | * acquired the subflow socket lock, too. | |
3618 | */ | |
7d803344 | 3619 | if (msk->fastopening) |
54f1944e PA |
3620 | err = __inet_stream_connect(ssock, uaddr, addr_len, msk->connect_flags, 1); |
3621 | else | |
3622 | err = inet_stream_connect(ssock, uaddr, addr_len, msk->connect_flags); | |
3623 | inet_sk(sk)->defer_connect = inet_sk(ssock->sk)->defer_connect; | |
3624 | ||
3625 | /* on successful connect, the msk state will be moved to established by | |
3626 | * subflow_finish_connect() | |
3627 | */ | |
3628 | if (unlikely(err && err != -EINPROGRESS)) { | |
3629 | inet_sk_state_store(sk, inet_sk_state_load(ssock->sk)); | |
3630 | return err; | |
3631 | } | |
3632 | ||
3633 | mptcp_copy_inaddrs(sk, ssock->sk); | |
3634 | ||
3635 | /* unblocking connect, mptcp-level inet_stream_connect will error out | |
3636 | * without changing the socket state, update it here. | |
3637 | */ | |
3638 | if (err == -EINPROGRESS) | |
3639 | sk->sk_socket->state = ssock->state; | |
3640 | return err; | |
3641 | } | |
3642 | ||
f870fa0b MM |
3643 | static struct proto mptcp_prot = { |
3644 | .name = "MPTCP", | |
3645 | .owner = THIS_MODULE, | |
3646 | .init = mptcp_init_sock, | |
54f1944e | 3647 | .connect = mptcp_connect, |
18b683bf | 3648 | .disconnect = mptcp_disconnect, |
f870fa0b | 3649 | .close = mptcp_close, |
cf7da0d6 | 3650 | .accept = mptcp_accept, |
717e79c8 PK |
3651 | .setsockopt = mptcp_setsockopt, |
3652 | .getsockopt = mptcp_getsockopt, | |
76e2a55d | 3653 | .shutdown = mptcp_shutdown, |
79c0949e | 3654 | .destroy = mptcp_destroy, |
f870fa0b | 3655 | .sendmsg = mptcp_sendmsg, |
644807e3 | 3656 | .ioctl = mptcp_ioctl, |
f870fa0b | 3657 | .recvmsg = mptcp_recvmsg, |
14c441b5 | 3658 | .release_cb = mptcp_release_cb, |
2c5ebd00 PA |
3659 | .hash = mptcp_hash, |
3660 | .unhash = mptcp_unhash, | |
cec37a6e | 3661 | .get_port = mptcp_get_port, |
6511882c | 3662 | .forward_alloc_get = mptcp_forward_alloc_get, |
d027236c | 3663 | .sockets_allocated = &mptcp_sockets_allocated, |
0defbb0a | 3664 | |
d027236c | 3665 | .memory_allocated = &tcp_memory_allocated, |
0defbb0a ED |
3666 | .per_cpu_fw_alloc = &tcp_memory_per_cpu_fw_alloc, |
3667 | ||
d027236c | 3668 | .memory_pressure = &tcp_memory_pressure, |
d027236c | 3669 | .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_tcp_wmem), |
989ef49b | 3670 | .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_tcp_rmem), |
d027236c | 3671 | .sysctl_mem = sysctl_tcp_mem, |
f870fa0b | 3672 | .obj_size = sizeof(struct mptcp_sock), |
2c5ebd00 | 3673 | .slab_flags = SLAB_TYPESAFE_BY_RCU, |
f870fa0b MM |
3674 | .no_autobind = true, |
3675 | }; | |
3676 | ||
2303f994 PK |
3677 | static int mptcp_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) |
3678 | { | |
3679 | struct mptcp_sock *msk = mptcp_sk(sock->sk); | |
3680 | struct socket *ssock; | |
cf7da0d6 | 3681 | int err; |
2303f994 PK |
3682 | |
3683 | lock_sock(sock->sk); | |
fa68018d | 3684 | ssock = __mptcp_nmpc_socket(msk); |
ddb1a072 PA |
3685 | if (IS_ERR(ssock)) { |
3686 | err = PTR_ERR(ssock); | |
2303f994 PK |
3687 | goto unlock; |
3688 | } | |
3689 | ||
3690 | err = ssock->ops->bind(ssock, uaddr, addr_len); | |
cf7da0d6 PK |
3691 | if (!err) |
3692 | mptcp_copy_inaddrs(sock->sk, ssock->sk); | |
2303f994 PK |
3693 | |
3694 | unlock: | |
3695 | release_sock(sock->sk); | |
3696 | return err; | |
3697 | } | |
3698 | ||
3699 | static int mptcp_stream_connect(struct socket *sock, struct sockaddr *uaddr, | |
3700 | int addr_len, int flags) | |
3701 | { | |
54f1944e | 3702 | int ret; |
2303f994 PK |
3703 | |
3704 | lock_sock(sock->sk); | |
54f1944e PA |
3705 | mptcp_sk(sock->sk)->connect_flags = flags; |
3706 | ret = __inet_stream_connect(sock, uaddr, addr_len, flags, 0); | |
2303f994 | 3707 | release_sock(sock->sk); |
54f1944e | 3708 | return ret; |
2303f994 PK |
3709 | } |
3710 | ||
cf7da0d6 PK |
3711 | static int mptcp_listen(struct socket *sock, int backlog) |
3712 | { | |
3713 | struct mptcp_sock *msk = mptcp_sk(sock->sk); | |
cfdcfeed | 3714 | struct sock *sk = sock->sk; |
cf7da0d6 PK |
3715 | struct socket *ssock; |
3716 | int err; | |
3717 | ||
3718 | pr_debug("msk=%p", msk); | |
3719 | ||
cfdcfeed | 3720 | lock_sock(sk); |
fa68018d | 3721 | ssock = __mptcp_nmpc_socket(msk); |
ddb1a072 PA |
3722 | if (IS_ERR(ssock)) { |
3723 | err = PTR_ERR(ssock); | |
cf7da0d6 PK |
3724 | goto unlock; |
3725 | } | |
3726 | ||
fa68018d | 3727 | mptcp_token_destroy(msk); |
cfdcfeed MD |
3728 | inet_sk_state_store(sk, TCP_LISTEN); |
3729 | sock_set_flag(sk, SOCK_RCU_FREE); | |
5e20087d | 3730 | |
cf7da0d6 | 3731 | err = ssock->ops->listen(ssock, backlog); |
cfdcfeed | 3732 | inet_sk_state_store(sk, inet_sk_state_load(ssock->sk)); |
c558246e MD |
3733 | if (!err) { |
3734 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); | |
cfdcfeed | 3735 | mptcp_copy_inaddrs(sk, ssock->sk); |
c558246e | 3736 | } |
cf7da0d6 | 3737 | |
f8c9dfbd GT |
3738 | mptcp_event_pm_listener(ssock->sk, MPTCP_EVENT_LISTENER_CREATED); |
3739 | ||
cf7da0d6 | 3740 | unlock: |
cfdcfeed | 3741 | release_sock(sk); |
cf7da0d6 PK |
3742 | return err; |
3743 | } | |
3744 | ||
cf7da0d6 PK |
3745 | static int mptcp_stream_accept(struct socket *sock, struct socket *newsock, |
3746 | int flags, bool kern) | |
3747 | { | |
3748 | struct mptcp_sock *msk = mptcp_sk(sock->sk); | |
3749 | struct socket *ssock; | |
3750 | int err; | |
3751 | ||
3752 | pr_debug("msk=%p", msk); | |
3753 | ||
61761231 PA |
3754 | /* buggy applications can call accept on socket states other then LISTEN |
3755 | * but no need to allocate the first subflow just to error out. | |
3756 | */ | |
3757 | ssock = msk->subflow; | |
cf7da0d6 | 3758 | if (!ssock) |
71ba088c | 3759 | return -EINVAL; |
cf7da0d6 PK |
3760 | |
3761 | err = ssock->ops->accept(sock, newsock, flags, kern); | |
d2f77c53 | 3762 | if (err == 0 && !mptcp_is_tcpsk(newsock->sk)) { |
cf7da0d6 PK |
3763 | struct mptcp_sock *msk = mptcp_sk(newsock->sk); |
3764 | struct mptcp_subflow_context *subflow; | |
0397c6d8 | 3765 | struct sock *newsk = newsock->sk; |
0397c6d8 | 3766 | |
a5ef058d | 3767 | set_bit(SOCK_CUSTOM_SOCKOPT, &newsock->flags); |
b6985b9b | 3768 | msk->in_accept_queue = 0; |
a5ef058d | 3769 | |
4d54cc32 | 3770 | lock_sock(newsk); |
5b950ff4 | 3771 | |
cf7da0d6 PK |
3772 | /* set ssk->sk_socket of accept()ed flows to mptcp socket. |
3773 | * This is needed so NOSPACE flag can be set from tcp stack. | |
3774 | */ | |
190f8b06 | 3775 | mptcp_for_each_subflow(msk, subflow) { |
cf7da0d6 PK |
3776 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); |
3777 | ||
3778 | if (!ssk->sk_socket) | |
3779 | mptcp_sock_graft(ssk, newsock); | |
3780 | } | |
63740448 PA |
3781 | |
3782 | /* Do late cleanup for the first subflow as necessary. Also | |
3783 | * deal with bad peers not doing a complete shutdown. | |
3784 | */ | |
3785 | if (msk->first && | |
3786 | unlikely(inet_sk_state_load(msk->first) == TCP_CLOSE)) { | |
3787 | __mptcp_close_ssk(newsk, msk->first, | |
3788 | mptcp_subflow_ctx(msk->first), 0); | |
3789 | if (unlikely(list_empty(&msk->conn_list))) | |
3790 | inet_sk_state_store(newsk, TCP_CLOSE); | |
3791 | } | |
3792 | ||
4d54cc32 | 3793 | release_sock(newsk); |
cf7da0d6 PK |
3794 | } |
3795 | ||
cf7da0d6 | 3796 | return err; |
cf7da0d6 PK |
3797 | } |
3798 | ||
8edf0864 FW |
3799 | static __poll_t mptcp_check_writeable(struct mptcp_sock *msk) |
3800 | { | |
3801 | struct sock *sk = (struct sock *)msk; | |
8edf0864 FW |
3802 | |
3803 | if (unlikely(sk->sk_shutdown & SEND_SHUTDOWN)) | |
dd913410 | 3804 | return EPOLLOUT | EPOLLWRNORM; |
8edf0864 FW |
3805 | |
3806 | if (sk_stream_is_writeable(sk)) | |
3807 | return EPOLLOUT | EPOLLWRNORM; | |
3808 | ||
5cf92bba | 3809 | mptcp_set_nospace(sk); |
6e628cd3 PA |
3810 | smp_mb__after_atomic(); /* msk->flags is changed by write_space cb */ |
3811 | if (sk_stream_is_writeable(sk)) | |
3812 | return EPOLLOUT | EPOLLWRNORM; | |
8edf0864 | 3813 | |
6e628cd3 | 3814 | return 0; |
8edf0864 FW |
3815 | } |
3816 | ||
2303f994 PK |
3817 | static __poll_t mptcp_poll(struct file *file, struct socket *sock, |
3818 | struct poll_table_struct *wait) | |
3819 | { | |
1891c4a0 | 3820 | struct sock *sk = sock->sk; |
8ab183de | 3821 | struct mptcp_sock *msk; |
2303f994 | 3822 | __poll_t mask = 0; |
8a05661b | 3823 | int state; |
2303f994 | 3824 | |
1891c4a0 | 3825 | msk = mptcp_sk(sk); |
1891c4a0 | 3826 | sock_poll_wait(file, sock, wait); |
1891c4a0 | 3827 | |
8a05661b | 3828 | state = inet_sk_state_load(sk); |
6719331c | 3829 | pr_debug("msk=%p state=%d flags=%lx", msk, state, msk->flags); |
71ba088c PA |
3830 | if (state == TCP_LISTEN) { |
3831 | if (WARN_ON_ONCE(!msk->subflow || !msk->subflow->sk)) | |
3832 | return 0; | |
3833 | ||
3834 | return inet_csk_listen_poll(msk->subflow->sk); | |
3835 | } | |
8a05661b PA |
3836 | |
3837 | if (state != TCP_SYN_SENT && state != TCP_SYN_RECV) { | |
3838 | mask |= mptcp_check_readable(msk); | |
8edf0864 | 3839 | mask |= mptcp_check_writeable(msk); |
a42cf9d1 BH |
3840 | } else if (state == TCP_SYN_SENT && inet_sk(sk)->defer_connect) { |
3841 | /* cf tcp_poll() note about TFO */ | |
3842 | mask |= EPOLLOUT | EPOLLWRNORM; | |
8a05661b | 3843 | } |
dd913410 PA |
3844 | if (sk->sk_shutdown == SHUTDOWN_MASK || state == TCP_CLOSE) |
3845 | mask |= EPOLLHUP; | |
1891c4a0 FW |
3846 | if (sk->sk_shutdown & RCV_SHUTDOWN) |
3847 | mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP; | |
3848 | ||
d89e3ed7 | 3849 | /* This barrier is coupled with smp_wmb() in __mptcp_error_report() */ |
15cc1045 | 3850 | smp_rmb(); |
9ae8e5ad | 3851 | if (READ_ONCE(sk->sk_err)) |
15cc1045 PA |
3852 | mask |= EPOLLERR; |
3853 | ||
2303f994 PK |
3854 | return mask; |
3855 | } | |
3856 | ||
e42f1ac6 FW |
3857 | static const struct proto_ops mptcp_stream_ops = { |
3858 | .family = PF_INET, | |
3859 | .owner = THIS_MODULE, | |
0a3cc579 | 3860 | .release = inet_release, |
e42f1ac6 FW |
3861 | .bind = mptcp_bind, |
3862 | .connect = mptcp_stream_connect, | |
3863 | .socketpair = sock_no_socketpair, | |
3864 | .accept = mptcp_stream_accept, | |
d2f77c53 | 3865 | .getname = inet_getname, |
e42f1ac6 FW |
3866 | .poll = mptcp_poll, |
3867 | .ioctl = inet_ioctl, | |
3868 | .gettstamp = sock_gettstamp, | |
3869 | .listen = mptcp_listen, | |
76e2a55d | 3870 | .shutdown = inet_shutdown, |
e42f1ac6 FW |
3871 | .setsockopt = sock_common_setsockopt, |
3872 | .getsockopt = sock_common_getsockopt, | |
3873 | .sendmsg = inet_sendmsg, | |
3874 | .recvmsg = inet_recvmsg, | |
3875 | .mmap = sock_no_mmap, | |
3876 | .sendpage = inet_sendpage, | |
e42f1ac6 | 3877 | }; |
2303f994 | 3878 | |
f870fa0b MM |
3879 | static struct inet_protosw mptcp_protosw = { |
3880 | .type = SOCK_STREAM, | |
3881 | .protocol = IPPROTO_MPTCP, | |
3882 | .prot = &mptcp_prot, | |
2303f994 PK |
3883 | .ops = &mptcp_stream_ops, |
3884 | .flags = INET_PROTOSW_ICSK, | |
f870fa0b MM |
3885 | }; |
3886 | ||
b19bc294 PA |
3887 | static int mptcp_napi_poll(struct napi_struct *napi, int budget) |
3888 | { | |
3889 | struct mptcp_delegated_action *delegated; | |
3890 | struct mptcp_subflow_context *subflow; | |
3891 | int work_done = 0; | |
3892 | ||
3893 | delegated = container_of(napi, struct mptcp_delegated_action, napi); | |
3894 | while ((subflow = mptcp_subflow_delegated_next(delegated)) != NULL) { | |
3895 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); | |
3896 | ||
3897 | bh_lock_sock_nested(ssk); | |
3898 | if (!sock_owned_by_user(ssk) && | |
3899 | mptcp_subflow_has_delegated_action(subflow)) | |
3900 | mptcp_subflow_process_delegated(ssk); | |
3901 | /* ... elsewhere tcp_release_cb_override already processed | |
3902 | * the action or will do at next release_sock(). | |
3903 | * In both case must dequeue the subflow here - on the same | |
3904 | * CPU that scheduled it. | |
3905 | */ | |
3906 | bh_unlock_sock(ssk); | |
3907 | sock_put(ssk); | |
3908 | ||
3909 | if (++work_done == budget) | |
3910 | return budget; | |
3911 | } | |
3912 | ||
3913 | /* always provide a 0 'work_done' argument, so that napi_complete_done | |
3914 | * will not try accessing the NULL napi->dev ptr | |
3915 | */ | |
3916 | napi_complete_done(napi, 0); | |
3917 | return work_done; | |
3918 | } | |
3919 | ||
d39dceca | 3920 | void __init mptcp_proto_init(void) |
f870fa0b | 3921 | { |
b19bc294 PA |
3922 | struct mptcp_delegated_action *delegated; |
3923 | int cpu; | |
3924 | ||
2303f994 | 3925 | mptcp_prot.h.hashinfo = tcp_prot.h.hashinfo; |
2303f994 | 3926 | |
d027236c PA |
3927 | if (percpu_counter_init(&mptcp_sockets_allocated, 0, GFP_KERNEL)) |
3928 | panic("Failed to allocate MPTCP pcpu counter\n"); | |
3929 | ||
b19bc294 PA |
3930 | init_dummy_netdev(&mptcp_napi_dev); |
3931 | for_each_possible_cpu(cpu) { | |
3932 | delegated = per_cpu_ptr(&mptcp_delegated_actions, cpu); | |
3933 | INIT_LIST_HEAD(&delegated->head); | |
16d083e2 JK |
3934 | netif_napi_add_tx(&mptcp_napi_dev, &delegated->napi, |
3935 | mptcp_napi_poll); | |
b19bc294 PA |
3936 | napi_enable(&delegated->napi); |
3937 | } | |
3938 | ||
2303f994 | 3939 | mptcp_subflow_init(); |
1b1c7a0e | 3940 | mptcp_pm_init(); |
2c5ebd00 | 3941 | mptcp_token_init(); |
2303f994 | 3942 | |
f870fa0b MM |
3943 | if (proto_register(&mptcp_prot, 1) != 0) |
3944 | panic("Failed to register MPTCP proto.\n"); | |
3945 | ||
3946 | inet_register_protosw(&mptcp_protosw); | |
6771bfd9 FW |
3947 | |
3948 | BUILD_BUG_ON(sizeof(struct mptcp_skb_cb) > sizeof_field(struct sk_buff, cb)); | |
f870fa0b MM |
3949 | } |
3950 | ||
3951 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
e42f1ac6 FW |
3952 | static const struct proto_ops mptcp_v6_stream_ops = { |
3953 | .family = PF_INET6, | |
3954 | .owner = THIS_MODULE, | |
0a3cc579 | 3955 | .release = inet6_release, |
e42f1ac6 FW |
3956 | .bind = mptcp_bind, |
3957 | .connect = mptcp_stream_connect, | |
3958 | .socketpair = sock_no_socketpair, | |
3959 | .accept = mptcp_stream_accept, | |
d2f77c53 | 3960 | .getname = inet6_getname, |
e42f1ac6 FW |
3961 | .poll = mptcp_poll, |
3962 | .ioctl = inet6_ioctl, | |
3963 | .gettstamp = sock_gettstamp, | |
3964 | .listen = mptcp_listen, | |
76e2a55d | 3965 | .shutdown = inet_shutdown, |
e42f1ac6 FW |
3966 | .setsockopt = sock_common_setsockopt, |
3967 | .getsockopt = sock_common_getsockopt, | |
3968 | .sendmsg = inet6_sendmsg, | |
3969 | .recvmsg = inet6_recvmsg, | |
3970 | .mmap = sock_no_mmap, | |
3971 | .sendpage = inet_sendpage, | |
3972 | #ifdef CONFIG_COMPAT | |
3986912f | 3973 | .compat_ioctl = inet6_compat_ioctl, |
e42f1ac6 FW |
3974 | #endif |
3975 | }; | |
3976 | ||
f870fa0b MM |
3977 | static struct proto mptcp_v6_prot; |
3978 | ||
3979 | static struct inet_protosw mptcp_v6_protosw = { | |
3980 | .type = SOCK_STREAM, | |
3981 | .protocol = IPPROTO_MPTCP, | |
3982 | .prot = &mptcp_v6_prot, | |
2303f994 | 3983 | .ops = &mptcp_v6_stream_ops, |
f870fa0b MM |
3984 | .flags = INET_PROTOSW_ICSK, |
3985 | }; | |
3986 | ||
d39dceca | 3987 | int __init mptcp_proto_v6_init(void) |
f870fa0b MM |
3988 | { |
3989 | int err; | |
3990 | ||
3991 | mptcp_v6_prot = mptcp_prot; | |
3992 | strcpy(mptcp_v6_prot.name, "MPTCPv6"); | |
3993 | mptcp_v6_prot.slab = NULL; | |
b0519de8 | 3994 | mptcp_v6_prot.obj_size = sizeof(struct mptcp6_sock); |
f870fa0b MM |
3995 | |
3996 | err = proto_register(&mptcp_v6_prot, 1); | |
3997 | if (err) | |
3998 | return err; | |
3999 | ||
4000 | err = inet6_register_protosw(&mptcp_v6_protosw); | |
4001 | if (err) | |
4002 | proto_unregister(&mptcp_v6_prot); | |
4003 | ||
4004 | return err; | |
4005 | } | |
4006 | #endif |