Merge tag 'nfs-for-5.19-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
[linux-2.6-microblaze.git] / net / smc / af_smc.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
4  *
5  *  AF_SMC protocol family socket handler keeping the AF_INET sock address type
6  *  applies to SOCK_STREAM sockets only
7  *  offers an alternative communication option for TCP-protocol sockets
8  *  applicable with RoCE-cards only
9  *
10  *  Initial restrictions:
11  *    - support for alternate links postponed
12  *
13  *  Copyright IBM Corp. 2016, 2018
14  *
15  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
16  *              based on prototype from Frank Blaschka
17  */
18
19 #define KMSG_COMPONENT "smc"
20 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
21
22 #include <linux/module.h>
23 #include <linux/socket.h>
24 #include <linux/workqueue.h>
25 #include <linux/in.h>
26 #include <linux/sched/signal.h>
27 #include <linux/if_vlan.h>
28 #include <linux/rcupdate_wait.h>
29 #include <linux/ctype.h>
30
31 #include <net/sock.h>
32 #include <net/tcp.h>
33 #include <net/smc.h>
34 #include <asm/ioctls.h>
35
36 #include <net/net_namespace.h>
37 #include <net/netns/generic.h>
38 #include "smc_netns.h"
39
40 #include "smc.h"
41 #include "smc_clc.h"
42 #include "smc_llc.h"
43 #include "smc_cdc.h"
44 #include "smc_core.h"
45 #include "smc_ib.h"
46 #include "smc_ism.h"
47 #include "smc_pnet.h"
48 #include "smc_netlink.h"
49 #include "smc_tx.h"
50 #include "smc_rx.h"
51 #include "smc_close.h"
52 #include "smc_stats.h"
53 #include "smc_tracepoint.h"
54 #include "smc_sysctl.h"
55
56 static DEFINE_MUTEX(smc_server_lgr_pending);    /* serialize link group
57                                                  * creation on server
58                                                  */
59 static DEFINE_MUTEX(smc_client_lgr_pending);    /* serialize link group
60                                                  * creation on client
61                                                  */
62
63 static struct workqueue_struct  *smc_tcp_ls_wq; /* wq for tcp listen work */
64 struct workqueue_struct *smc_hs_wq;     /* wq for handshake work */
65 struct workqueue_struct *smc_close_wq;  /* wq for close work */
66
67 static void smc_tcp_listen_work(struct work_struct *);
68 static void smc_connect_work(struct work_struct *);
69
70 int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb)
71 {
72         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
73         void *hdr;
74
75         if (cb_ctx->pos[0])
76                 goto out;
77
78         hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
79                           &smc_gen_nl_family, NLM_F_MULTI,
80                           SMC_NETLINK_DUMP_HS_LIMITATION);
81         if (!hdr)
82                 return -ENOMEM;
83
84         if (nla_put_u8(skb, SMC_NLA_HS_LIMITATION_ENABLED,
85                        sock_net(skb->sk)->smc.limit_smc_hs))
86                 goto err;
87
88         genlmsg_end(skb, hdr);
89         cb_ctx->pos[0] = 1;
90 out:
91         return skb->len;
92 err:
93         genlmsg_cancel(skb, hdr);
94         return -EMSGSIZE;
95 }
96
97 int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
98 {
99         sock_net(skb->sk)->smc.limit_smc_hs = true;
100         return 0;
101 }
102
103 int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
104 {
105         sock_net(skb->sk)->smc.limit_smc_hs = false;
106         return 0;
107 }
108
109 static void smc_set_keepalive(struct sock *sk, int val)
110 {
111         struct smc_sock *smc = smc_sk(sk);
112
113         smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
114 }
115
116 static struct sock *smc_tcp_syn_recv_sock(const struct sock *sk,
117                                           struct sk_buff *skb,
118                                           struct request_sock *req,
119                                           struct dst_entry *dst,
120                                           struct request_sock *req_unhash,
121                                           bool *own_req)
122 {
123         struct smc_sock *smc;
124         struct sock *child;
125
126         smc = smc_clcsock_user_data(sk);
127
128         if (READ_ONCE(sk->sk_ack_backlog) + atomic_read(&smc->queued_smc_hs) >
129                                 sk->sk_max_ack_backlog)
130                 goto drop;
131
132         if (sk_acceptq_is_full(&smc->sk)) {
133                 NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
134                 goto drop;
135         }
136
137         /* passthrough to original syn recv sock fct */
138         child = smc->ori_af_ops->syn_recv_sock(sk, skb, req, dst, req_unhash,
139                                                own_req);
140         /* child must not inherit smc or its ops */
141         if (child) {
142                 rcu_assign_sk_user_data(child, NULL);
143
144                 /* v4-mapped sockets don't inherit parent ops. Don't restore. */
145                 if (inet_csk(child)->icsk_af_ops == inet_csk(sk)->icsk_af_ops)
146                         inet_csk(child)->icsk_af_ops = smc->ori_af_ops;
147         }
148         return child;
149
150 drop:
151         dst_release(dst);
152         tcp_listendrop(sk);
153         return NULL;
154 }
155
156 static bool smc_hs_congested(const struct sock *sk)
157 {
158         const struct smc_sock *smc;
159
160         smc = smc_clcsock_user_data(sk);
161
162         if (!smc)
163                 return true;
164
165         if (workqueue_congested(WORK_CPU_UNBOUND, smc_hs_wq))
166                 return true;
167
168         return false;
169 }
170
171 static struct smc_hashinfo smc_v4_hashinfo = {
172         .lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
173 };
174
175 static struct smc_hashinfo smc_v6_hashinfo = {
176         .lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
177 };
178
179 int smc_hash_sk(struct sock *sk)
180 {
181         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
182         struct hlist_head *head;
183
184         head = &h->ht;
185
186         write_lock_bh(&h->lock);
187         sk_add_node(sk, head);
188         write_unlock_bh(&h->lock);
189         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
190
191         return 0;
192 }
193 EXPORT_SYMBOL_GPL(smc_hash_sk);
194
195 void smc_unhash_sk(struct sock *sk)
196 {
197         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
198
199         write_lock_bh(&h->lock);
200         if (sk_del_node_init(sk))
201                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
202         write_unlock_bh(&h->lock);
203 }
204 EXPORT_SYMBOL_GPL(smc_unhash_sk);
205
206 /* This will be called before user really release sock_lock. So do the
207  * work which we didn't do because of user hold the sock_lock in the
208  * BH context
209  */
210 static void smc_release_cb(struct sock *sk)
211 {
212         struct smc_sock *smc = smc_sk(sk);
213
214         if (smc->conn.tx_in_release_sock) {
215                 smc_tx_pending(&smc->conn);
216                 smc->conn.tx_in_release_sock = false;
217         }
218 }
219
220 struct proto smc_proto = {
221         .name           = "SMC",
222         .owner          = THIS_MODULE,
223         .keepalive      = smc_set_keepalive,
224         .hash           = smc_hash_sk,
225         .unhash         = smc_unhash_sk,
226         .release_cb     = smc_release_cb,
227         .obj_size       = sizeof(struct smc_sock),
228         .h.smc_hash     = &smc_v4_hashinfo,
229         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
230 };
231 EXPORT_SYMBOL_GPL(smc_proto);
232
233 struct proto smc_proto6 = {
234         .name           = "SMC6",
235         .owner          = THIS_MODULE,
236         .keepalive      = smc_set_keepalive,
237         .hash           = smc_hash_sk,
238         .unhash         = smc_unhash_sk,
239         .release_cb     = smc_release_cb,
240         .obj_size       = sizeof(struct smc_sock),
241         .h.smc_hash     = &smc_v6_hashinfo,
242         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
243 };
244 EXPORT_SYMBOL_GPL(smc_proto6);
245
246 static void smc_fback_restore_callbacks(struct smc_sock *smc)
247 {
248         struct sock *clcsk = smc->clcsock->sk;
249
250         write_lock_bh(&clcsk->sk_callback_lock);
251         clcsk->sk_user_data = NULL;
252
253         smc_clcsock_restore_cb(&clcsk->sk_state_change, &smc->clcsk_state_change);
254         smc_clcsock_restore_cb(&clcsk->sk_data_ready, &smc->clcsk_data_ready);
255         smc_clcsock_restore_cb(&clcsk->sk_write_space, &smc->clcsk_write_space);
256         smc_clcsock_restore_cb(&clcsk->sk_error_report, &smc->clcsk_error_report);
257
258         write_unlock_bh(&clcsk->sk_callback_lock);
259 }
260
261 static void smc_restore_fallback_changes(struct smc_sock *smc)
262 {
263         if (smc->clcsock->file) { /* non-accepted sockets have no file yet */
264                 smc->clcsock->file->private_data = smc->sk.sk_socket;
265                 smc->clcsock->file = NULL;
266                 smc_fback_restore_callbacks(smc);
267         }
268 }
269
270 static int __smc_release(struct smc_sock *smc)
271 {
272         struct sock *sk = &smc->sk;
273         int rc = 0;
274
275         if (!smc->use_fallback) {
276                 rc = smc_close_active(smc);
277                 sock_set_flag(sk, SOCK_DEAD);
278                 sk->sk_shutdown |= SHUTDOWN_MASK;
279         } else {
280                 if (sk->sk_state != SMC_CLOSED) {
281                         if (sk->sk_state != SMC_LISTEN &&
282                             sk->sk_state != SMC_INIT)
283                                 sock_put(sk); /* passive closing */
284                         if (sk->sk_state == SMC_LISTEN) {
285                                 /* wake up clcsock accept */
286                                 rc = kernel_sock_shutdown(smc->clcsock,
287                                                           SHUT_RDWR);
288                         }
289                         sk->sk_state = SMC_CLOSED;
290                         sk->sk_state_change(sk);
291                 }
292                 smc_restore_fallback_changes(smc);
293         }
294
295         sk->sk_prot->unhash(sk);
296
297         if (sk->sk_state == SMC_CLOSED) {
298                 if (smc->clcsock) {
299                         release_sock(sk);
300                         smc_clcsock_release(smc);
301                         lock_sock(sk);
302                 }
303                 if (!smc->use_fallback)
304                         smc_conn_free(&smc->conn);
305         }
306
307         return rc;
308 }
309
310 static int smc_release(struct socket *sock)
311 {
312         struct sock *sk = sock->sk;
313         struct smc_sock *smc;
314         int old_state, rc = 0;
315
316         if (!sk)
317                 goto out;
318
319         sock_hold(sk); /* sock_put below */
320         smc = smc_sk(sk);
321
322         old_state = sk->sk_state;
323
324         /* cleanup for a dangling non-blocking connect */
325         if (smc->connect_nonblock && old_state == SMC_INIT)
326                 tcp_abort(smc->clcsock->sk, ECONNABORTED);
327
328         if (cancel_work_sync(&smc->connect_work))
329                 sock_put(&smc->sk); /* sock_hold in smc_connect for passive closing */
330
331         if (sk->sk_state == SMC_LISTEN)
332                 /* smc_close_non_accepted() is called and acquires
333                  * sock lock for child sockets again
334                  */
335                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
336         else
337                 lock_sock(sk);
338
339         if (old_state == SMC_INIT && sk->sk_state == SMC_ACTIVE &&
340             !smc->use_fallback)
341                 smc_close_active_abort(smc);
342
343         rc = __smc_release(smc);
344
345         /* detach socket */
346         sock_orphan(sk);
347         sock->sk = NULL;
348         release_sock(sk);
349
350         sock_put(sk); /* sock_hold above */
351         sock_put(sk); /* final sock_put */
352 out:
353         return rc;
354 }
355
356 static void smc_destruct(struct sock *sk)
357 {
358         if (sk->sk_state != SMC_CLOSED)
359                 return;
360         if (!sock_flag(sk, SOCK_DEAD))
361                 return;
362
363         sk_refcnt_debug_dec(sk);
364 }
365
366 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
367                                    int protocol)
368 {
369         struct smc_sock *smc;
370         struct proto *prot;
371         struct sock *sk;
372
373         prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
374         sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
375         if (!sk)
376                 return NULL;
377
378         sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
379         sk->sk_state = SMC_INIT;
380         sk->sk_destruct = smc_destruct;
381         sk->sk_protocol = protocol;
382         smc = smc_sk(sk);
383         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
384         INIT_WORK(&smc->connect_work, smc_connect_work);
385         INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
386         INIT_LIST_HEAD(&smc->accept_q);
387         spin_lock_init(&smc->accept_q_lock);
388         spin_lock_init(&smc->conn.send_lock);
389         sk->sk_prot->hash(sk);
390         sk_refcnt_debug_inc(sk);
391         mutex_init(&smc->clcsock_release_lock);
392         smc_init_saved_callbacks(smc);
393
394         return sk;
395 }
396
397 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
398                     int addr_len)
399 {
400         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
401         struct sock *sk = sock->sk;
402         struct smc_sock *smc;
403         int rc;
404
405         smc = smc_sk(sk);
406
407         /* replicate tests from inet_bind(), to be safe wrt. future changes */
408         rc = -EINVAL;
409         if (addr_len < sizeof(struct sockaddr_in))
410                 goto out;
411
412         rc = -EAFNOSUPPORT;
413         if (addr->sin_family != AF_INET &&
414             addr->sin_family != AF_INET6 &&
415             addr->sin_family != AF_UNSPEC)
416                 goto out;
417         /* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
418         if (addr->sin_family == AF_UNSPEC &&
419             addr->sin_addr.s_addr != htonl(INADDR_ANY))
420                 goto out;
421
422         lock_sock(sk);
423
424         /* Check if socket is already active */
425         rc = -EINVAL;
426         if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
427                 goto out_rel;
428
429         smc->clcsock->sk->sk_reuse = sk->sk_reuse;
430         rc = kernel_bind(smc->clcsock, uaddr, addr_len);
431
432 out_rel:
433         release_sock(sk);
434 out:
435         return rc;
436 }
437
438 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
439                                    unsigned long mask)
440 {
441         /* options we don't get control via setsockopt for */
442         nsk->sk_type = osk->sk_type;
443         nsk->sk_sndbuf = osk->sk_sndbuf;
444         nsk->sk_rcvbuf = osk->sk_rcvbuf;
445         nsk->sk_sndtimeo = osk->sk_sndtimeo;
446         nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
447         nsk->sk_mark = osk->sk_mark;
448         nsk->sk_priority = osk->sk_priority;
449         nsk->sk_rcvlowat = osk->sk_rcvlowat;
450         nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
451         nsk->sk_err = osk->sk_err;
452
453         nsk->sk_flags &= ~mask;
454         nsk->sk_flags |= osk->sk_flags & mask;
455 }
456
457 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
458                              (1UL << SOCK_KEEPOPEN) | \
459                              (1UL << SOCK_LINGER) | \
460                              (1UL << SOCK_BROADCAST) | \
461                              (1UL << SOCK_TIMESTAMP) | \
462                              (1UL << SOCK_DBG) | \
463                              (1UL << SOCK_RCVTSTAMP) | \
464                              (1UL << SOCK_RCVTSTAMPNS) | \
465                              (1UL << SOCK_LOCALROUTE) | \
466                              (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
467                              (1UL << SOCK_RXQ_OVFL) | \
468                              (1UL << SOCK_WIFI_STATUS) | \
469                              (1UL << SOCK_NOFCS) | \
470                              (1UL << SOCK_FILTER_LOCKED) | \
471                              (1UL << SOCK_TSTAMP_NEW))
472 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
473  * clc socket (since smc is not called for these options from net/core)
474  */
475 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
476 {
477         smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
478 }
479
480 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
481                              (1UL << SOCK_KEEPOPEN) | \
482                              (1UL << SOCK_LINGER) | \
483                              (1UL << SOCK_DBG))
484 /* copy only settings and flags relevant for smc from clc to smc socket */
485 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
486 {
487         smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
488 }
489
490 /* register the new rmb on all links */
491 static int smcr_lgr_reg_rmbs(struct smc_link *link,
492                              struct smc_buf_desc *rmb_desc)
493 {
494         struct smc_link_group *lgr = link->lgr;
495         int i, rc = 0;
496
497         rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
498         if (rc)
499                 return rc;
500         /* protect against parallel smc_llc_cli_rkey_exchange() and
501          * parallel smcr_link_reg_rmb()
502          */
503         mutex_lock(&lgr->llc_conf_mutex);
504         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
505                 if (!smc_link_active(&lgr->lnk[i]))
506                         continue;
507                 rc = smcr_link_reg_rmb(&lgr->lnk[i], rmb_desc);
508                 if (rc)
509                         goto out;
510         }
511
512         /* exchange confirm_rkey msg with peer */
513         rc = smc_llc_do_confirm_rkey(link, rmb_desc);
514         if (rc) {
515                 rc = -EFAULT;
516                 goto out;
517         }
518         rmb_desc->is_conf_rkey = true;
519 out:
520         mutex_unlock(&lgr->llc_conf_mutex);
521         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
522         return rc;
523 }
524
525 static int smcr_clnt_conf_first_link(struct smc_sock *smc)
526 {
527         struct smc_link *link = smc->conn.lnk;
528         struct smc_llc_qentry *qentry;
529         int rc;
530
531         /* receive CONFIRM LINK request from server over RoCE fabric */
532         qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
533                               SMC_LLC_CONFIRM_LINK);
534         if (!qentry) {
535                 struct smc_clc_msg_decline dclc;
536
537                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
538                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
539                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
540         }
541         smc_llc_save_peer_uid(qentry);
542         rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
543         smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
544         if (rc)
545                 return SMC_CLC_DECL_RMBE_EC;
546
547         rc = smc_ib_modify_qp_rts(link);
548         if (rc)
549                 return SMC_CLC_DECL_ERR_RDYLNK;
550
551         smc_wr_remember_qp_attr(link);
552
553         if (smcr_link_reg_rmb(link, smc->conn.rmb_desc))
554                 return SMC_CLC_DECL_ERR_REGRMB;
555
556         /* confirm_rkey is implicit on 1st contact */
557         smc->conn.rmb_desc->is_conf_rkey = true;
558
559         /* send CONFIRM LINK response over RoCE fabric */
560         rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
561         if (rc < 0)
562                 return SMC_CLC_DECL_TIMEOUT_CL;
563
564         smc_llc_link_active(link);
565         smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
566
567         /* optional 2nd link, receive ADD LINK request from server */
568         qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
569                               SMC_LLC_ADD_LINK);
570         if (!qentry) {
571                 struct smc_clc_msg_decline dclc;
572
573                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
574                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
575                 if (rc == -EAGAIN)
576                         rc = 0; /* no DECLINE received, go with one link */
577                 return rc;
578         }
579         smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
580         smc_llc_cli_add_link(link, qentry);
581         return 0;
582 }
583
584 static bool smc_isascii(char *hostname)
585 {
586         int i;
587
588         for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
589                 if (!isascii(hostname[i]))
590                         return false;
591         return true;
592 }
593
594 static void smc_conn_save_peer_info_fce(struct smc_sock *smc,
595                                         struct smc_clc_msg_accept_confirm *clc)
596 {
597         struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
598                 (struct smc_clc_msg_accept_confirm_v2 *)clc;
599         struct smc_clc_first_contact_ext *fce;
600         int clc_v2_len;
601
602         if (clc->hdr.version == SMC_V1 ||
603             !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
604                 return;
605
606         if (smc->conn.lgr->is_smcd) {
607                 memcpy(smc->conn.lgr->negotiated_eid, clc_v2->d1.eid,
608                        SMC_MAX_EID_LEN);
609                 clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
610                                          d1);
611         } else {
612                 memcpy(smc->conn.lgr->negotiated_eid, clc_v2->r1.eid,
613                        SMC_MAX_EID_LEN);
614                 clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
615                                          r1);
616         }
617         fce = (struct smc_clc_first_contact_ext *)(((u8 *)clc_v2) + clc_v2_len);
618         smc->conn.lgr->peer_os = fce->os_type;
619         smc->conn.lgr->peer_smc_release = fce->release;
620         if (smc_isascii(fce->hostname))
621                 memcpy(smc->conn.lgr->peer_hostname, fce->hostname,
622                        SMC_MAX_HOSTNAME_LEN);
623 }
624
625 static void smcr_conn_save_peer_info(struct smc_sock *smc,
626                                      struct smc_clc_msg_accept_confirm *clc)
627 {
628         int bufsize = smc_uncompress_bufsize(clc->r0.rmbe_size);
629
630         smc->conn.peer_rmbe_idx = clc->r0.rmbe_idx;
631         smc->conn.local_tx_ctrl.token = ntohl(clc->r0.rmbe_alert_token);
632         smc->conn.peer_rmbe_size = bufsize;
633         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
634         smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
635 }
636
637 static void smcd_conn_save_peer_info(struct smc_sock *smc,
638                                      struct smc_clc_msg_accept_confirm *clc)
639 {
640         int bufsize = smc_uncompress_bufsize(clc->d0.dmbe_size);
641
642         smc->conn.peer_rmbe_idx = clc->d0.dmbe_idx;
643         smc->conn.peer_token = clc->d0.token;
644         /* msg header takes up space in the buffer */
645         smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
646         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
647         smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
648 }
649
650 static void smc_conn_save_peer_info(struct smc_sock *smc,
651                                     struct smc_clc_msg_accept_confirm *clc)
652 {
653         if (smc->conn.lgr->is_smcd)
654                 smcd_conn_save_peer_info(smc, clc);
655         else
656                 smcr_conn_save_peer_info(smc, clc);
657         smc_conn_save_peer_info_fce(smc, clc);
658 }
659
660 static void smc_link_save_peer_info(struct smc_link *link,
661                                     struct smc_clc_msg_accept_confirm *clc,
662                                     struct smc_init_info *ini)
663 {
664         link->peer_qpn = ntoh24(clc->r0.qpn);
665         memcpy(link->peer_gid, ini->peer_gid, SMC_GID_SIZE);
666         memcpy(link->peer_mac, ini->peer_mac, sizeof(link->peer_mac));
667         link->peer_psn = ntoh24(clc->r0.psn);
668         link->peer_mtu = clc->r0.qp_mtu;
669 }
670
671 static void smc_stat_inc_fback_rsn_cnt(struct smc_sock *smc,
672                                        struct smc_stats_fback *fback_arr)
673 {
674         int cnt;
675
676         for (cnt = 0; cnt < SMC_MAX_FBACK_RSN_CNT; cnt++) {
677                 if (fback_arr[cnt].fback_code == smc->fallback_rsn) {
678                         fback_arr[cnt].count++;
679                         break;
680                 }
681                 if (!fback_arr[cnt].fback_code) {
682                         fback_arr[cnt].fback_code = smc->fallback_rsn;
683                         fback_arr[cnt].count++;
684                         break;
685                 }
686         }
687 }
688
689 static void smc_stat_fallback(struct smc_sock *smc)
690 {
691         struct net *net = sock_net(&smc->sk);
692
693         mutex_lock(&net->smc.mutex_fback_rsn);
694         if (smc->listen_smc) {
695                 smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->srv);
696                 net->smc.fback_rsn->srv_fback_cnt++;
697         } else {
698                 smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->clnt);
699                 net->smc.fback_rsn->clnt_fback_cnt++;
700         }
701         mutex_unlock(&net->smc.mutex_fback_rsn);
702 }
703
704 /* must be called under rcu read lock */
705 static void smc_fback_wakeup_waitqueue(struct smc_sock *smc, void *key)
706 {
707         struct socket_wq *wq;
708         __poll_t flags;
709
710         wq = rcu_dereference(smc->sk.sk_wq);
711         if (!skwq_has_sleeper(wq))
712                 return;
713
714         /* wake up smc sk->sk_wq */
715         if (!key) {
716                 /* sk_state_change */
717                 wake_up_interruptible_all(&wq->wait);
718         } else {
719                 flags = key_to_poll(key);
720                 if (flags & (EPOLLIN | EPOLLOUT))
721                         /* sk_data_ready or sk_write_space */
722                         wake_up_interruptible_sync_poll(&wq->wait, flags);
723                 else if (flags & EPOLLERR)
724                         /* sk_error_report */
725                         wake_up_interruptible_poll(&wq->wait, flags);
726         }
727 }
728
729 static int smc_fback_mark_woken(wait_queue_entry_t *wait,
730                                 unsigned int mode, int sync, void *key)
731 {
732         struct smc_mark_woken *mark =
733                 container_of(wait, struct smc_mark_woken, wait_entry);
734
735         mark->woken = true;
736         mark->key = key;
737         return 0;
738 }
739
740 static void smc_fback_forward_wakeup(struct smc_sock *smc, struct sock *clcsk,
741                                      void (*clcsock_callback)(struct sock *sk))
742 {
743         struct smc_mark_woken mark = { .woken = false };
744         struct socket_wq *wq;
745
746         init_waitqueue_func_entry(&mark.wait_entry,
747                                   smc_fback_mark_woken);
748         rcu_read_lock();
749         wq = rcu_dereference(clcsk->sk_wq);
750         if (!wq)
751                 goto out;
752         add_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
753         clcsock_callback(clcsk);
754         remove_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
755
756         if (mark.woken)
757                 smc_fback_wakeup_waitqueue(smc, mark.key);
758 out:
759         rcu_read_unlock();
760 }
761
762 static void smc_fback_state_change(struct sock *clcsk)
763 {
764         struct smc_sock *smc;
765
766         read_lock_bh(&clcsk->sk_callback_lock);
767         smc = smc_clcsock_user_data(clcsk);
768         if (smc)
769                 smc_fback_forward_wakeup(smc, clcsk,
770                                          smc->clcsk_state_change);
771         read_unlock_bh(&clcsk->sk_callback_lock);
772 }
773
774 static void smc_fback_data_ready(struct sock *clcsk)
775 {
776         struct smc_sock *smc;
777
778         read_lock_bh(&clcsk->sk_callback_lock);
779         smc = smc_clcsock_user_data(clcsk);
780         if (smc)
781                 smc_fback_forward_wakeup(smc, clcsk,
782                                          smc->clcsk_data_ready);
783         read_unlock_bh(&clcsk->sk_callback_lock);
784 }
785
786 static void smc_fback_write_space(struct sock *clcsk)
787 {
788         struct smc_sock *smc;
789
790         read_lock_bh(&clcsk->sk_callback_lock);
791         smc = smc_clcsock_user_data(clcsk);
792         if (smc)
793                 smc_fback_forward_wakeup(smc, clcsk,
794                                          smc->clcsk_write_space);
795         read_unlock_bh(&clcsk->sk_callback_lock);
796 }
797
798 static void smc_fback_error_report(struct sock *clcsk)
799 {
800         struct smc_sock *smc;
801
802         read_lock_bh(&clcsk->sk_callback_lock);
803         smc = smc_clcsock_user_data(clcsk);
804         if (smc)
805                 smc_fback_forward_wakeup(smc, clcsk,
806                                          smc->clcsk_error_report);
807         read_unlock_bh(&clcsk->sk_callback_lock);
808 }
809
810 static void smc_fback_replace_callbacks(struct smc_sock *smc)
811 {
812         struct sock *clcsk = smc->clcsock->sk;
813
814         write_lock_bh(&clcsk->sk_callback_lock);
815         clcsk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
816
817         smc_clcsock_replace_cb(&clcsk->sk_state_change, smc_fback_state_change,
818                                &smc->clcsk_state_change);
819         smc_clcsock_replace_cb(&clcsk->sk_data_ready, smc_fback_data_ready,
820                                &smc->clcsk_data_ready);
821         smc_clcsock_replace_cb(&clcsk->sk_write_space, smc_fback_write_space,
822                                &smc->clcsk_write_space);
823         smc_clcsock_replace_cb(&clcsk->sk_error_report, smc_fback_error_report,
824                                &smc->clcsk_error_report);
825
826         write_unlock_bh(&clcsk->sk_callback_lock);
827 }
828
829 static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code)
830 {
831         int rc = 0;
832
833         mutex_lock(&smc->clcsock_release_lock);
834         if (!smc->clcsock) {
835                 rc = -EBADF;
836                 goto out;
837         }
838
839         smc->use_fallback = true;
840         smc->fallback_rsn = reason_code;
841         smc_stat_fallback(smc);
842         trace_smc_switch_to_fallback(smc, reason_code);
843         if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
844                 smc->clcsock->file = smc->sk.sk_socket->file;
845                 smc->clcsock->file->private_data = smc->clcsock;
846                 smc->clcsock->wq.fasync_list =
847                         smc->sk.sk_socket->wq.fasync_list;
848
849                 /* There might be some wait entries remaining
850                  * in smc sk->sk_wq and they should be woken up
851                  * as clcsock's wait queue is woken up.
852                  */
853                 smc_fback_replace_callbacks(smc);
854         }
855 out:
856         mutex_unlock(&smc->clcsock_release_lock);
857         return rc;
858 }
859
860 /* fall back during connect */
861 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
862 {
863         struct net *net = sock_net(&smc->sk);
864         int rc = 0;
865
866         rc = smc_switch_to_fallback(smc, reason_code);
867         if (rc) { /* fallback fails */
868                 this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
869                 if (smc->sk.sk_state == SMC_INIT)
870                         sock_put(&smc->sk); /* passive closing */
871                 return rc;
872         }
873         smc_copy_sock_settings_to_clc(smc);
874         smc->connect_nonblock = 0;
875         if (smc->sk.sk_state == SMC_INIT)
876                 smc->sk.sk_state = SMC_ACTIVE;
877         return 0;
878 }
879
880 /* decline and fall back during connect */
881 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
882                                         u8 version)
883 {
884         struct net *net = sock_net(&smc->sk);
885         int rc;
886
887         if (reason_code < 0) { /* error, fallback is not possible */
888                 this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
889                 if (smc->sk.sk_state == SMC_INIT)
890                         sock_put(&smc->sk); /* passive closing */
891                 return reason_code;
892         }
893         if (reason_code != SMC_CLC_DECL_PEERDECL) {
894                 rc = smc_clc_send_decline(smc, reason_code, version);
895                 if (rc < 0) {
896                         this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
897                         if (smc->sk.sk_state == SMC_INIT)
898                                 sock_put(&smc->sk); /* passive closing */
899                         return rc;
900                 }
901         }
902         return smc_connect_fallback(smc, reason_code);
903 }
904
905 static void smc_conn_abort(struct smc_sock *smc, int local_first)
906 {
907         struct smc_connection *conn = &smc->conn;
908         struct smc_link_group *lgr = conn->lgr;
909         bool lgr_valid = false;
910
911         if (smc_conn_lgr_valid(conn))
912                 lgr_valid = true;
913
914         smc_conn_free(conn);
915         if (local_first && lgr_valid)
916                 smc_lgr_cleanup_early(lgr);
917 }
918
919 /* check if there is a rdma device available for this connection. */
920 /* called for connect and listen */
921 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
922 {
923         /* PNET table look up: search active ib_device and port
924          * within same PNETID that also contains the ethernet device
925          * used for the internal TCP socket
926          */
927         smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
928         if (!ini->check_smcrv2 && !ini->ib_dev)
929                 return SMC_CLC_DECL_NOSMCRDEV;
930         if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
931                 return SMC_CLC_DECL_NOSMCRDEV;
932         return 0;
933 }
934
935 /* check if there is an ISM device available for this connection. */
936 /* called for connect and listen */
937 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
938 {
939         /* Find ISM device with same PNETID as connecting interface  */
940         smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
941         if (!ini->ism_dev[0])
942                 return SMC_CLC_DECL_NOSMCDDEV;
943         else
944                 ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
945         return 0;
946 }
947
948 /* is chid unique for the ism devices that are already determined? */
949 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
950                                            int cnt)
951 {
952         int i = (!ini->ism_dev[0]) ? 1 : 0;
953
954         for (; i < cnt; i++)
955                 if (ini->ism_chid[i] == chid)
956                         return false;
957         return true;
958 }
959
960 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
961  * PNETID matching net_device)
962  */
963 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
964                                        struct smc_init_info *ini)
965 {
966         int rc = SMC_CLC_DECL_NOSMCDDEV;
967         struct smcd_dev *smcd;
968         int i = 1;
969         u16 chid;
970
971         if (smcd_indicated(ini->smc_type_v1))
972                 rc = 0;         /* already initialized for V1 */
973         mutex_lock(&smcd_dev_list.mutex);
974         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
975                 if (smcd->going_away || smcd == ini->ism_dev[0])
976                         continue;
977                 chid = smc_ism_get_chid(smcd);
978                 if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
979                         continue;
980                 if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
981                     smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
982                         ini->ism_dev[i] = smcd;
983                         ini->ism_chid[i] = chid;
984                         ini->is_smcd = true;
985                         rc = 0;
986                         i++;
987                         if (i > SMC_MAX_ISM_DEVS)
988                                 break;
989                 }
990         }
991         mutex_unlock(&smcd_dev_list.mutex);
992         ini->ism_offered_cnt = i - 1;
993         if (!ini->ism_dev[0] && !ini->ism_dev[1])
994                 ini->smcd_version = 0;
995
996         return rc;
997 }
998
999 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
1000 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
1001                                       struct smc_init_info *ini)
1002 {
1003         if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
1004                 return SMC_CLC_DECL_ISMVLANERR;
1005         return 0;
1006 }
1007
1008 static int smc_find_proposal_devices(struct smc_sock *smc,
1009                                      struct smc_init_info *ini)
1010 {
1011         int rc = 0;
1012
1013         /* check if there is an ism device available */
1014         if (!(ini->smcd_version & SMC_V1) ||
1015             smc_find_ism_device(smc, ini) ||
1016             smc_connect_ism_vlan_setup(smc, ini))
1017                 ini->smcd_version &= ~SMC_V1;
1018         /* else ISM V1 is supported for this connection */
1019
1020         /* check if there is an rdma device available */
1021         if (!(ini->smcr_version & SMC_V1) ||
1022             smc_find_rdma_device(smc, ini))
1023                 ini->smcr_version &= ~SMC_V1;
1024         /* else RDMA is supported for this connection */
1025
1026         ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
1027                                               ini->smcr_version & SMC_V1);
1028
1029         /* check if there is an ism v2 device available */
1030         if (!(ini->smcd_version & SMC_V2) ||
1031             !smc_ism_is_v2_capable() ||
1032             smc_find_ism_v2_device_clnt(smc, ini))
1033                 ini->smcd_version &= ~SMC_V2;
1034
1035         /* check if there is an rdma v2 device available */
1036         ini->check_smcrv2 = true;
1037         ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
1038         if (!(ini->smcr_version & SMC_V2) ||
1039             smc->clcsock->sk->sk_family != AF_INET ||
1040             !smc_clc_ueid_count() ||
1041             smc_find_rdma_device(smc, ini))
1042                 ini->smcr_version &= ~SMC_V2;
1043         ini->check_smcrv2 = false;
1044
1045         ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
1046                                               ini->smcr_version & SMC_V2);
1047
1048         /* if neither ISM nor RDMA are supported, fallback */
1049         if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
1050                 rc = SMC_CLC_DECL_NOSMCDEV;
1051
1052         return rc;
1053 }
1054
1055 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
1056  * used, the VLAN ID will be registered again during the connection setup.
1057  */
1058 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
1059                                         struct smc_init_info *ini)
1060 {
1061         if (!smcd_indicated(ini->smc_type_v1))
1062                 return 0;
1063         if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
1064                 return SMC_CLC_DECL_CNFERR;
1065         return 0;
1066 }
1067
1068 #define SMC_CLC_MAX_ACCEPT_LEN \
1069         (sizeof(struct smc_clc_msg_accept_confirm_v2) + \
1070          sizeof(struct smc_clc_first_contact_ext) + \
1071          sizeof(struct smc_clc_msg_trail))
1072
1073 /* CLC handshake during connect */
1074 static int smc_connect_clc(struct smc_sock *smc,
1075                            struct smc_clc_msg_accept_confirm_v2 *aclc2,
1076                            struct smc_init_info *ini)
1077 {
1078         int rc = 0;
1079
1080         /* do inband token exchange */
1081         rc = smc_clc_send_proposal(smc, ini);
1082         if (rc)
1083                 return rc;
1084         /* receive SMC Accept CLC message */
1085         return smc_clc_wait_msg(smc, aclc2, SMC_CLC_MAX_ACCEPT_LEN,
1086                                 SMC_CLC_ACCEPT, CLC_WAIT_TIME);
1087 }
1088
1089 void smc_fill_gid_list(struct smc_link_group *lgr,
1090                        struct smc_gidlist *gidlist,
1091                        struct smc_ib_device *known_dev, u8 *known_gid)
1092 {
1093         struct smc_init_info *alt_ini = NULL;
1094
1095         memset(gidlist, 0, sizeof(*gidlist));
1096         memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
1097
1098         alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
1099         if (!alt_ini)
1100                 goto out;
1101
1102         alt_ini->vlan_id = lgr->vlan_id;
1103         alt_ini->check_smcrv2 = true;
1104         alt_ini->smcrv2.saddr = lgr->saddr;
1105         smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
1106
1107         if (!alt_ini->smcrv2.ib_dev_v2)
1108                 goto out;
1109
1110         memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
1111                SMC_GID_SIZE);
1112
1113 out:
1114         kfree(alt_ini);
1115 }
1116
1117 static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
1118                                        struct smc_clc_msg_accept_confirm *aclc,
1119                                        struct smc_init_info *ini)
1120 {
1121         struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1122                 (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1123         struct smc_clc_first_contact_ext *fce =
1124                 (struct smc_clc_first_contact_ext *)
1125                         (((u8 *)clc_v2) + sizeof(*clc_v2));
1126
1127         if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1128                 return 0;
1129
1130         if (fce->v2_direct) {
1131                 memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1132                 ini->smcrv2.uses_gateway = false;
1133         } else {
1134                 if (smc_ib_find_route(smc->clcsock->sk->sk_rcv_saddr,
1135                                       smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1136                                       ini->smcrv2.nexthop_mac,
1137                                       &ini->smcrv2.uses_gateway))
1138                         return SMC_CLC_DECL_NOROUTE;
1139                 if (!ini->smcrv2.uses_gateway) {
1140                         /* mismatch: peer claims indirect, but its direct */
1141                         return SMC_CLC_DECL_NOINDIRECT;
1142                 }
1143         }
1144         return 0;
1145 }
1146
1147 /* setup for RDMA connection of client */
1148 static int smc_connect_rdma(struct smc_sock *smc,
1149                             struct smc_clc_msg_accept_confirm *aclc,
1150                             struct smc_init_info *ini)
1151 {
1152         int i, reason_code = 0;
1153         struct smc_link *link;
1154         u8 *eid = NULL;
1155
1156         ini->is_smcd = false;
1157         ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1158         ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1159         memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1160         memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1161         memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1162
1163         reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1164         if (reason_code)
1165                 return reason_code;
1166
1167         mutex_lock(&smc_client_lgr_pending);
1168         reason_code = smc_conn_create(smc, ini);
1169         if (reason_code) {
1170                 mutex_unlock(&smc_client_lgr_pending);
1171                 return reason_code;
1172         }
1173
1174         smc_conn_save_peer_info(smc, aclc);
1175
1176         if (ini->first_contact_local) {
1177                 link = smc->conn.lnk;
1178         } else {
1179                 /* set link that was assigned by server */
1180                 link = NULL;
1181                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1182                         struct smc_link *l = &smc->conn.lgr->lnk[i];
1183
1184                         if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1185                             !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1186                                     SMC_GID_SIZE) &&
1187                             (aclc->hdr.version > SMC_V1 ||
1188                              !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1189                                      sizeof(l->peer_mac)))) {
1190                                 link = l;
1191                                 break;
1192                         }
1193                 }
1194                 if (!link) {
1195                         reason_code = SMC_CLC_DECL_NOSRVLINK;
1196                         goto connect_abort;
1197                 }
1198                 smc_switch_link_and_count(&smc->conn, link);
1199         }
1200
1201         /* create send buffer and rmb */
1202         if (smc_buf_create(smc, false)) {
1203                 reason_code = SMC_CLC_DECL_MEM;
1204                 goto connect_abort;
1205         }
1206
1207         if (ini->first_contact_local)
1208                 smc_link_save_peer_info(link, aclc, ini);
1209
1210         if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1211                 reason_code = SMC_CLC_DECL_ERR_RTOK;
1212                 goto connect_abort;
1213         }
1214
1215         smc_close_init(smc);
1216         smc_rx_init(smc);
1217
1218         if (ini->first_contact_local) {
1219                 if (smc_ib_ready_link(link)) {
1220                         reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1221                         goto connect_abort;
1222                 }
1223         } else {
1224                 if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1225                         reason_code = SMC_CLC_DECL_ERR_REGRMB;
1226                         goto connect_abort;
1227                 }
1228         }
1229         smc_rmb_sync_sg_for_device(&smc->conn);
1230
1231         if (aclc->hdr.version > SMC_V1) {
1232                 struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1233                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1234
1235                 eid = clc_v2->r1.eid;
1236                 if (ini->first_contact_local)
1237                         smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1238                                           link->smcibdev, link->gid);
1239         }
1240
1241         reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1242                                            aclc->hdr.version, eid, ini);
1243         if (reason_code)
1244                 goto connect_abort;
1245
1246         smc_tx_init(smc);
1247
1248         if (ini->first_contact_local) {
1249                 /* QP confirmation over RoCE fabric */
1250                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1251                 reason_code = smcr_clnt_conf_first_link(smc);
1252                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1253                 if (reason_code)
1254                         goto connect_abort;
1255         }
1256         mutex_unlock(&smc_client_lgr_pending);
1257
1258         smc_copy_sock_settings_to_clc(smc);
1259         smc->connect_nonblock = 0;
1260         if (smc->sk.sk_state == SMC_INIT)
1261                 smc->sk.sk_state = SMC_ACTIVE;
1262
1263         return 0;
1264 connect_abort:
1265         smc_conn_abort(smc, ini->first_contact_local);
1266         mutex_unlock(&smc_client_lgr_pending);
1267         smc->connect_nonblock = 0;
1268
1269         return reason_code;
1270 }
1271
1272 /* The server has chosen one of the proposed ISM devices for the communication.
1273  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1274  */
1275 static int
1276 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm_v2 *aclc,
1277                                struct smc_init_info *ini)
1278 {
1279         int i;
1280
1281         for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1282                 if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1283                         ini->ism_selected = i;
1284                         return 0;
1285                 }
1286         }
1287
1288         return -EPROTO;
1289 }
1290
1291 /* setup for ISM connection of client */
1292 static int smc_connect_ism(struct smc_sock *smc,
1293                            struct smc_clc_msg_accept_confirm *aclc,
1294                            struct smc_init_info *ini)
1295 {
1296         u8 *eid = NULL;
1297         int rc = 0;
1298
1299         ini->is_smcd = true;
1300         ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1301
1302         if (aclc->hdr.version == SMC_V2) {
1303                 struct smc_clc_msg_accept_confirm_v2 *aclc_v2 =
1304                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1305
1306                 rc = smc_v2_determine_accepted_chid(aclc_v2, ini);
1307                 if (rc)
1308                         return rc;
1309         }
1310         ini->ism_peer_gid[ini->ism_selected] = aclc->d0.gid;
1311
1312         /* there is only one lgr role for SMC-D; use server lock */
1313         mutex_lock(&smc_server_lgr_pending);
1314         rc = smc_conn_create(smc, ini);
1315         if (rc) {
1316                 mutex_unlock(&smc_server_lgr_pending);
1317                 return rc;
1318         }
1319
1320         /* Create send and receive buffers */
1321         rc = smc_buf_create(smc, true);
1322         if (rc) {
1323                 rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1324                 goto connect_abort;
1325         }
1326
1327         smc_conn_save_peer_info(smc, aclc);
1328         smc_close_init(smc);
1329         smc_rx_init(smc);
1330         smc_tx_init(smc);
1331
1332         if (aclc->hdr.version > SMC_V1) {
1333                 struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1334                         (struct smc_clc_msg_accept_confirm_v2 *)aclc;
1335
1336                 eid = clc_v2->d1.eid;
1337         }
1338
1339         rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1340                                   aclc->hdr.version, eid, NULL);
1341         if (rc)
1342                 goto connect_abort;
1343         mutex_unlock(&smc_server_lgr_pending);
1344
1345         smc_copy_sock_settings_to_clc(smc);
1346         smc->connect_nonblock = 0;
1347         if (smc->sk.sk_state == SMC_INIT)
1348                 smc->sk.sk_state = SMC_ACTIVE;
1349
1350         return 0;
1351 connect_abort:
1352         smc_conn_abort(smc, ini->first_contact_local);
1353         mutex_unlock(&smc_server_lgr_pending);
1354         smc->connect_nonblock = 0;
1355
1356         return rc;
1357 }
1358
1359 /* check if received accept type and version matches a proposed one */
1360 static int smc_connect_check_aclc(struct smc_init_info *ini,
1361                                   struct smc_clc_msg_accept_confirm *aclc)
1362 {
1363         if (aclc->hdr.typev1 != SMC_TYPE_R &&
1364             aclc->hdr.typev1 != SMC_TYPE_D)
1365                 return SMC_CLC_DECL_MODEUNSUPP;
1366
1367         if (aclc->hdr.version >= SMC_V2) {
1368                 if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1369                      !smcr_indicated(ini->smc_type_v2)) ||
1370                     (aclc->hdr.typev1 == SMC_TYPE_D &&
1371                      !smcd_indicated(ini->smc_type_v2)))
1372                         return SMC_CLC_DECL_MODEUNSUPP;
1373         } else {
1374                 if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1375                      !smcr_indicated(ini->smc_type_v1)) ||
1376                     (aclc->hdr.typev1 == SMC_TYPE_D &&
1377                      !smcd_indicated(ini->smc_type_v1)))
1378                         return SMC_CLC_DECL_MODEUNSUPP;
1379         }
1380
1381         return 0;
1382 }
1383
1384 /* perform steps before actually connecting */
1385 static int __smc_connect(struct smc_sock *smc)
1386 {
1387         u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1388         struct smc_clc_msg_accept_confirm_v2 *aclc2;
1389         struct smc_clc_msg_accept_confirm *aclc;
1390         struct smc_init_info *ini = NULL;
1391         u8 *buf = NULL;
1392         int rc = 0;
1393
1394         if (smc->use_fallback)
1395                 return smc_connect_fallback(smc, smc->fallback_rsn);
1396
1397         /* if peer has not signalled SMC-capability, fall back */
1398         if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1399                 return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1400
1401         /* IPSec connections opt out of SMC optimizations */
1402         if (using_ipsec(smc))
1403                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1404                                                     version);
1405
1406         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1407         if (!ini)
1408                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1409                                                     version);
1410
1411         ini->smcd_version = SMC_V1 | SMC_V2;
1412         ini->smcr_version = SMC_V1 | SMC_V2;
1413         ini->smc_type_v1 = SMC_TYPE_B;
1414         ini->smc_type_v2 = SMC_TYPE_B;
1415
1416         /* get vlan id from IP device */
1417         if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1418                 ini->smcd_version &= ~SMC_V1;
1419                 ini->smcr_version = 0;
1420                 ini->smc_type_v1 = SMC_TYPE_N;
1421                 if (!ini->smcd_version) {
1422                         rc = SMC_CLC_DECL_GETVLANERR;
1423                         goto fallback;
1424                 }
1425         }
1426
1427         rc = smc_find_proposal_devices(smc, ini);
1428         if (rc)
1429                 goto fallback;
1430
1431         buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1432         if (!buf) {
1433                 rc = SMC_CLC_DECL_MEM;
1434                 goto fallback;
1435         }
1436         aclc2 = (struct smc_clc_msg_accept_confirm_v2 *)buf;
1437         aclc = (struct smc_clc_msg_accept_confirm *)aclc2;
1438
1439         /* perform CLC handshake */
1440         rc = smc_connect_clc(smc, aclc2, ini);
1441         if (rc) {
1442                 /* -EAGAIN on timeout, see tcp_recvmsg() */
1443                 if (rc == -EAGAIN) {
1444                         rc = -ETIMEDOUT;
1445                         smc->sk.sk_err = ETIMEDOUT;
1446                 }
1447                 goto vlan_cleanup;
1448         }
1449
1450         /* check if smc modes and versions of CLC proposal and accept match */
1451         rc = smc_connect_check_aclc(ini, aclc);
1452         version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1453         if (rc)
1454                 goto vlan_cleanup;
1455
1456         /* depending on previous steps, connect using rdma or ism */
1457         if (aclc->hdr.typev1 == SMC_TYPE_R) {
1458                 ini->smcr_version = version;
1459                 rc = smc_connect_rdma(smc, aclc, ini);
1460         } else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1461                 ini->smcd_version = version;
1462                 rc = smc_connect_ism(smc, aclc, ini);
1463         }
1464         if (rc)
1465                 goto vlan_cleanup;
1466
1467         SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1468         smc_connect_ism_vlan_cleanup(smc, ini);
1469         kfree(buf);
1470         kfree(ini);
1471         return 0;
1472
1473 vlan_cleanup:
1474         smc_connect_ism_vlan_cleanup(smc, ini);
1475         kfree(buf);
1476 fallback:
1477         kfree(ini);
1478         return smc_connect_decline_fallback(smc, rc, version);
1479 }
1480
1481 static void smc_connect_work(struct work_struct *work)
1482 {
1483         struct smc_sock *smc = container_of(work, struct smc_sock,
1484                                             connect_work);
1485         long timeo = smc->sk.sk_sndtimeo;
1486         int rc = 0;
1487
1488         if (!timeo)
1489                 timeo = MAX_SCHEDULE_TIMEOUT;
1490         lock_sock(smc->clcsock->sk);
1491         if (smc->clcsock->sk->sk_err) {
1492                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
1493         } else if ((1 << smc->clcsock->sk->sk_state) &
1494                                         (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1495                 rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1496                 if ((rc == -EPIPE) &&
1497                     ((1 << smc->clcsock->sk->sk_state) &
1498                                         (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1499                         rc = 0;
1500         }
1501         release_sock(smc->clcsock->sk);
1502         lock_sock(&smc->sk);
1503         if (rc != 0 || smc->sk.sk_err) {
1504                 smc->sk.sk_state = SMC_CLOSED;
1505                 if (rc == -EPIPE || rc == -EAGAIN)
1506                         smc->sk.sk_err = EPIPE;
1507                 else if (rc == -ECONNREFUSED)
1508                         smc->sk.sk_err = ECONNREFUSED;
1509                 else if (signal_pending(current))
1510                         smc->sk.sk_err = -sock_intr_errno(timeo);
1511                 sock_put(&smc->sk); /* passive closing */
1512                 goto out;
1513         }
1514
1515         rc = __smc_connect(smc);
1516         if (rc < 0)
1517                 smc->sk.sk_err = -rc;
1518
1519 out:
1520         if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1521                 if (smc->sk.sk_err) {
1522                         smc->sk.sk_state_change(&smc->sk);
1523                 } else { /* allow polling before and after fallback decision */
1524                         smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1525                         smc->sk.sk_write_space(&smc->sk);
1526                 }
1527         }
1528         release_sock(&smc->sk);
1529 }
1530
1531 static int smc_connect(struct socket *sock, struct sockaddr *addr,
1532                        int alen, int flags)
1533 {
1534         struct sock *sk = sock->sk;
1535         struct smc_sock *smc;
1536         int rc = -EINVAL;
1537
1538         smc = smc_sk(sk);
1539
1540         /* separate smc parameter checking to be safe */
1541         if (alen < sizeof(addr->sa_family))
1542                 goto out_err;
1543         if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1544                 goto out_err;
1545
1546         lock_sock(sk);
1547         switch (sock->state) {
1548         default:
1549                 rc = -EINVAL;
1550                 goto out;
1551         case SS_CONNECTED:
1552                 rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1553                 goto out;
1554         case SS_CONNECTING:
1555                 if (sk->sk_state == SMC_ACTIVE)
1556                         goto connected;
1557                 break;
1558         case SS_UNCONNECTED:
1559                 sock->state = SS_CONNECTING;
1560                 break;
1561         }
1562
1563         switch (sk->sk_state) {
1564         default:
1565                 goto out;
1566         case SMC_CLOSED:
1567                 rc = sock_error(sk) ? : -ECONNABORTED;
1568                 sock->state = SS_UNCONNECTED;
1569                 goto out;
1570         case SMC_ACTIVE:
1571                 rc = -EISCONN;
1572                 goto out;
1573         case SMC_INIT:
1574                 break;
1575         }
1576
1577         smc_copy_sock_settings_to_clc(smc);
1578         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1579         if (smc->connect_nonblock) {
1580                 rc = -EALREADY;
1581                 goto out;
1582         }
1583         rc = kernel_connect(smc->clcsock, addr, alen, flags);
1584         if (rc && rc != -EINPROGRESS)
1585                 goto out;
1586
1587         if (smc->use_fallback) {
1588                 sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1589                 goto out;
1590         }
1591         sock_hold(&smc->sk); /* sock put in passive closing */
1592         if (flags & O_NONBLOCK) {
1593                 if (queue_work(smc_hs_wq, &smc->connect_work))
1594                         smc->connect_nonblock = 1;
1595                 rc = -EINPROGRESS;
1596                 goto out;
1597         } else {
1598                 rc = __smc_connect(smc);
1599                 if (rc < 0)
1600                         goto out;
1601         }
1602
1603 connected:
1604         rc = 0;
1605         sock->state = SS_CONNECTED;
1606 out:
1607         release_sock(sk);
1608 out_err:
1609         return rc;
1610 }
1611
1612 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1613 {
1614         struct socket *new_clcsock = NULL;
1615         struct sock *lsk = &lsmc->sk;
1616         struct sock *new_sk;
1617         int rc = -EINVAL;
1618
1619         release_sock(lsk);
1620         new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1621         if (!new_sk) {
1622                 rc = -ENOMEM;
1623                 lsk->sk_err = ENOMEM;
1624                 *new_smc = NULL;
1625                 lock_sock(lsk);
1626                 goto out;
1627         }
1628         *new_smc = smc_sk(new_sk);
1629
1630         mutex_lock(&lsmc->clcsock_release_lock);
1631         if (lsmc->clcsock)
1632                 rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1633         mutex_unlock(&lsmc->clcsock_release_lock);
1634         lock_sock(lsk);
1635         if  (rc < 0 && rc != -EAGAIN)
1636                 lsk->sk_err = -rc;
1637         if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1638                 new_sk->sk_prot->unhash(new_sk);
1639                 if (new_clcsock)
1640                         sock_release(new_clcsock);
1641                 new_sk->sk_state = SMC_CLOSED;
1642                 sock_set_flag(new_sk, SOCK_DEAD);
1643                 sock_put(new_sk); /* final */
1644                 *new_smc = NULL;
1645                 goto out;
1646         }
1647
1648         /* new clcsock has inherited the smc listen-specific sk_data_ready
1649          * function; switch it back to the original sk_data_ready function
1650          */
1651         new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1652
1653         /* if new clcsock has also inherited the fallback-specific callback
1654          * functions, switch them back to the original ones.
1655          */
1656         if (lsmc->use_fallback) {
1657                 if (lsmc->clcsk_state_change)
1658                         new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1659                 if (lsmc->clcsk_write_space)
1660                         new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1661                 if (lsmc->clcsk_error_report)
1662                         new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1663         }
1664
1665         (*new_smc)->clcsock = new_clcsock;
1666 out:
1667         return rc;
1668 }
1669
1670 /* add a just created sock to the accept queue of the listen sock as
1671  * candidate for a following socket accept call from user space
1672  */
1673 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1674 {
1675         struct smc_sock *par = smc_sk(parent);
1676
1677         sock_hold(sk); /* sock_put in smc_accept_unlink () */
1678         spin_lock(&par->accept_q_lock);
1679         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1680         spin_unlock(&par->accept_q_lock);
1681         sk_acceptq_added(parent);
1682 }
1683
1684 /* remove a socket from the accept queue of its parental listening socket */
1685 static void smc_accept_unlink(struct sock *sk)
1686 {
1687         struct smc_sock *par = smc_sk(sk)->listen_smc;
1688
1689         spin_lock(&par->accept_q_lock);
1690         list_del_init(&smc_sk(sk)->accept_q);
1691         spin_unlock(&par->accept_q_lock);
1692         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1693         sock_put(sk); /* sock_hold in smc_accept_enqueue */
1694 }
1695
1696 /* remove a sock from the accept queue to bind it to a new socket created
1697  * for a socket accept call from user space
1698  */
1699 struct sock *smc_accept_dequeue(struct sock *parent,
1700                                 struct socket *new_sock)
1701 {
1702         struct smc_sock *isk, *n;
1703         struct sock *new_sk;
1704
1705         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1706                 new_sk = (struct sock *)isk;
1707
1708                 smc_accept_unlink(new_sk);
1709                 if (new_sk->sk_state == SMC_CLOSED) {
1710                         new_sk->sk_prot->unhash(new_sk);
1711                         if (isk->clcsock) {
1712                                 sock_release(isk->clcsock);
1713                                 isk->clcsock = NULL;
1714                         }
1715                         sock_put(new_sk); /* final */
1716                         continue;
1717                 }
1718                 if (new_sock) {
1719                         sock_graft(new_sk, new_sock);
1720                         new_sock->state = SS_CONNECTED;
1721                         if (isk->use_fallback) {
1722                                 smc_sk(new_sk)->clcsock->file = new_sock->file;
1723                                 isk->clcsock->file->private_data = isk->clcsock;
1724                         }
1725                 }
1726                 return new_sk;
1727         }
1728         return NULL;
1729 }
1730
1731 /* clean up for a created but never accepted sock */
1732 void smc_close_non_accepted(struct sock *sk)
1733 {
1734         struct smc_sock *smc = smc_sk(sk);
1735
1736         sock_hold(sk); /* sock_put below */
1737         lock_sock(sk);
1738         if (!sk->sk_lingertime)
1739                 /* wait for peer closing */
1740                 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
1741         __smc_release(smc);
1742         release_sock(sk);
1743         sock_put(sk); /* sock_hold above */
1744         sock_put(sk); /* final sock_put */
1745 }
1746
1747 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1748 {
1749         struct smc_link *link = smc->conn.lnk;
1750         struct smc_llc_qentry *qentry;
1751         int rc;
1752
1753         if (smcr_link_reg_rmb(link, smc->conn.rmb_desc))
1754                 return SMC_CLC_DECL_ERR_REGRMB;
1755
1756         /* send CONFIRM LINK request to client over the RoCE fabric */
1757         rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1758         if (rc < 0)
1759                 return SMC_CLC_DECL_TIMEOUT_CL;
1760
1761         /* receive CONFIRM LINK response from client over the RoCE fabric */
1762         qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1763                               SMC_LLC_CONFIRM_LINK);
1764         if (!qentry) {
1765                 struct smc_clc_msg_decline dclc;
1766
1767                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1768                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1769                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1770         }
1771         smc_llc_save_peer_uid(qentry);
1772         rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1773         smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1774         if (rc)
1775                 return SMC_CLC_DECL_RMBE_EC;
1776
1777         /* confirm_rkey is implicit on 1st contact */
1778         smc->conn.rmb_desc->is_conf_rkey = true;
1779
1780         smc_llc_link_active(link);
1781         smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1782
1783         /* initial contact - try to establish second link */
1784         smc_llc_srv_add_link(link, NULL);
1785         return 0;
1786 }
1787
1788 /* listen worker: finish */
1789 static void smc_listen_out(struct smc_sock *new_smc)
1790 {
1791         struct smc_sock *lsmc = new_smc->listen_smc;
1792         struct sock *newsmcsk = &new_smc->sk;
1793
1794         if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1795                 atomic_dec(&lsmc->queued_smc_hs);
1796
1797         if (lsmc->sk.sk_state == SMC_LISTEN) {
1798                 lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1799                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
1800                 release_sock(&lsmc->sk);
1801         } else { /* no longer listening */
1802                 smc_close_non_accepted(newsmcsk);
1803         }
1804
1805         /* Wake up accept */
1806         lsmc->sk.sk_data_ready(&lsmc->sk);
1807         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1808 }
1809
1810 /* listen worker: finish in state connected */
1811 static void smc_listen_out_connected(struct smc_sock *new_smc)
1812 {
1813         struct sock *newsmcsk = &new_smc->sk;
1814
1815         sk_refcnt_debug_inc(newsmcsk);
1816         if (newsmcsk->sk_state == SMC_INIT)
1817                 newsmcsk->sk_state = SMC_ACTIVE;
1818
1819         smc_listen_out(new_smc);
1820 }
1821
1822 /* listen worker: finish in error state */
1823 static void smc_listen_out_err(struct smc_sock *new_smc)
1824 {
1825         struct sock *newsmcsk = &new_smc->sk;
1826         struct net *net = sock_net(newsmcsk);
1827
1828         this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1829         if (newsmcsk->sk_state == SMC_INIT)
1830                 sock_put(&new_smc->sk); /* passive closing */
1831         newsmcsk->sk_state = SMC_CLOSED;
1832
1833         smc_listen_out(new_smc);
1834 }
1835
1836 /* listen worker: decline and fall back if possible */
1837 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1838                                int local_first, u8 version)
1839 {
1840         /* RDMA setup failed, switch back to TCP */
1841         smc_conn_abort(new_smc, local_first);
1842         if (reason_code < 0 ||
1843             smc_switch_to_fallback(new_smc, reason_code)) {
1844                 /* error, no fallback possible */
1845                 smc_listen_out_err(new_smc);
1846                 return;
1847         }
1848         if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1849                 if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1850                         smc_listen_out_err(new_smc);
1851                         return;
1852                 }
1853         }
1854         smc_listen_out_connected(new_smc);
1855 }
1856
1857 /* listen worker: version checking */
1858 static int smc_listen_v2_check(struct smc_sock *new_smc,
1859                                struct smc_clc_msg_proposal *pclc,
1860                                struct smc_init_info *ini)
1861 {
1862         struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1863         struct smc_clc_v2_extension *pclc_v2_ext;
1864         int rc = SMC_CLC_DECL_PEERNOSMC;
1865
1866         ini->smc_type_v1 = pclc->hdr.typev1;
1867         ini->smc_type_v2 = pclc->hdr.typev2;
1868         ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1869         ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1870         if (pclc->hdr.version > SMC_V1) {
1871                 if (smcd_indicated(ini->smc_type_v2))
1872                         ini->smcd_version |= SMC_V2;
1873                 if (smcr_indicated(ini->smc_type_v2))
1874                         ini->smcr_version |= SMC_V2;
1875         }
1876         if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1877                 rc = SMC_CLC_DECL_PEERNOSMC;
1878                 goto out;
1879         }
1880         pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1881         if (!pclc_v2_ext) {
1882                 ini->smcd_version &= ~SMC_V2;
1883                 ini->smcr_version &= ~SMC_V2;
1884                 rc = SMC_CLC_DECL_NOV2EXT;
1885                 goto out;
1886         }
1887         pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
1888         if (ini->smcd_version & SMC_V2) {
1889                 if (!smc_ism_is_v2_capable()) {
1890                         ini->smcd_version &= ~SMC_V2;
1891                         rc = SMC_CLC_DECL_NOISM2SUPP;
1892                 } else if (!pclc_smcd_v2_ext) {
1893                         ini->smcd_version &= ~SMC_V2;
1894                         rc = SMC_CLC_DECL_NOV2DEXT;
1895                 } else if (!pclc_v2_ext->hdr.eid_cnt &&
1896                            !pclc_v2_ext->hdr.flag.seid) {
1897                         ini->smcd_version &= ~SMC_V2;
1898                         rc = SMC_CLC_DECL_NOUEID;
1899                 }
1900         }
1901         if (ini->smcr_version & SMC_V2) {
1902                 if (!pclc_v2_ext->hdr.eid_cnt) {
1903                         ini->smcr_version &= ~SMC_V2;
1904                         rc = SMC_CLC_DECL_NOUEID;
1905                 }
1906         }
1907
1908 out:
1909         if (!ini->smcd_version && !ini->smcr_version)
1910                 return rc;
1911
1912         return 0;
1913 }
1914
1915 /* listen worker: check prefixes */
1916 static int smc_listen_prfx_check(struct smc_sock *new_smc,
1917                                  struct smc_clc_msg_proposal *pclc)
1918 {
1919         struct smc_clc_msg_proposal_prefix *pclc_prfx;
1920         struct socket *newclcsock = new_smc->clcsock;
1921
1922         if (pclc->hdr.typev1 == SMC_TYPE_N)
1923                 return 0;
1924         pclc_prfx = smc_clc_proposal_get_prefix(pclc);
1925         if (smc_clc_prfx_match(newclcsock, pclc_prfx))
1926                 return SMC_CLC_DECL_DIFFPREFIX;
1927
1928         return 0;
1929 }
1930
1931 /* listen worker: initialize connection and buffers */
1932 static int smc_listen_rdma_init(struct smc_sock *new_smc,
1933                                 struct smc_init_info *ini)
1934 {
1935         int rc;
1936
1937         /* allocate connection / link group */
1938         rc = smc_conn_create(new_smc, ini);
1939         if (rc)
1940                 return rc;
1941
1942         /* create send buffer and rmb */
1943         if (smc_buf_create(new_smc, false))
1944                 return SMC_CLC_DECL_MEM;
1945
1946         return 0;
1947 }
1948
1949 /* listen worker: initialize connection and buffers for SMC-D */
1950 static int smc_listen_ism_init(struct smc_sock *new_smc,
1951                                struct smc_init_info *ini)
1952 {
1953         int rc;
1954
1955         rc = smc_conn_create(new_smc, ini);
1956         if (rc)
1957                 return rc;
1958
1959         /* Create send and receive buffers */
1960         rc = smc_buf_create(new_smc, true);
1961         if (rc) {
1962                 smc_conn_abort(new_smc, ini->first_contact_local);
1963                 return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
1964                                          SMC_CLC_DECL_MEM;
1965         }
1966
1967         return 0;
1968 }
1969
1970 static bool smc_is_already_selected(struct smcd_dev *smcd,
1971                                     struct smc_init_info *ini,
1972                                     int matches)
1973 {
1974         int i;
1975
1976         for (i = 0; i < matches; i++)
1977                 if (smcd == ini->ism_dev[i])
1978                         return true;
1979
1980         return false;
1981 }
1982
1983 /* check for ISM devices matching proposed ISM devices */
1984 static void smc_check_ism_v2_match(struct smc_init_info *ini,
1985                                    u16 proposed_chid, u64 proposed_gid,
1986                                    unsigned int *matches)
1987 {
1988         struct smcd_dev *smcd;
1989
1990         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1991                 if (smcd->going_away)
1992                         continue;
1993                 if (smc_is_already_selected(smcd, ini, *matches))
1994                         continue;
1995                 if (smc_ism_get_chid(smcd) == proposed_chid &&
1996                     !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
1997                         ini->ism_peer_gid[*matches] = proposed_gid;
1998                         ini->ism_dev[*matches] = smcd;
1999                         (*matches)++;
2000                         break;
2001                 }
2002         }
2003 }
2004
2005 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2006 {
2007         if (!ini->rc)
2008                 ini->rc = rc;
2009 }
2010
2011 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2012                                         struct smc_clc_msg_proposal *pclc,
2013                                         struct smc_init_info *ini)
2014 {
2015         struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2016         struct smc_clc_v2_extension *smc_v2_ext;
2017         struct smc_clc_msg_smcd *pclc_smcd;
2018         unsigned int matches = 0;
2019         u8 smcd_version;
2020         u8 *eid = NULL;
2021         int i, rc;
2022
2023         if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2024                 goto not_found;
2025
2026         pclc_smcd = smc_get_clc_msg_smcd(pclc);
2027         smc_v2_ext = smc_get_clc_v2_ext(pclc);
2028         smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2029
2030         mutex_lock(&smcd_dev_list.mutex);
2031         if (pclc_smcd->ism.chid)
2032                 /* check for ISM device matching proposed native ISM device */
2033                 smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2034                                        ntohll(pclc_smcd->ism.gid), &matches);
2035         for (i = 1; i <= smc_v2_ext->hdr.ism_gid_cnt; i++) {
2036                 /* check for ISM devices matching proposed non-native ISM
2037                  * devices
2038                  */
2039                 smc_check_ism_v2_match(ini,
2040                                        ntohs(smcd_v2_ext->gidchid[i - 1].chid),
2041                                        ntohll(smcd_v2_ext->gidchid[i - 1].gid),
2042                                        &matches);
2043         }
2044         mutex_unlock(&smcd_dev_list.mutex);
2045
2046         if (!ini->ism_dev[0]) {
2047                 smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2048                 goto not_found;
2049         }
2050
2051         smc_ism_get_system_eid(&eid);
2052         if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2053                                smcd_v2_ext->system_eid, eid))
2054                 goto not_found;
2055
2056         /* separate - outside the smcd_dev_list.lock */
2057         smcd_version = ini->smcd_version;
2058         for (i = 0; i < matches; i++) {
2059                 ini->smcd_version = SMC_V2;
2060                 ini->is_smcd = true;
2061                 ini->ism_selected = i;
2062                 rc = smc_listen_ism_init(new_smc, ini);
2063                 if (rc) {
2064                         smc_find_ism_store_rc(rc, ini);
2065                         /* try next active ISM device */
2066                         continue;
2067                 }
2068                 return; /* matching and usable V2 ISM device found */
2069         }
2070         /* no V2 ISM device could be initialized */
2071         ini->smcd_version = smcd_version;       /* restore original value */
2072         ini->negotiated_eid[0] = 0;
2073
2074 not_found:
2075         ini->smcd_version &= ~SMC_V2;
2076         ini->ism_dev[0] = NULL;
2077         ini->is_smcd = false;
2078 }
2079
2080 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2081                                         struct smc_clc_msg_proposal *pclc,
2082                                         struct smc_init_info *ini)
2083 {
2084         struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2085         int rc = 0;
2086
2087         /* check if ISM V1 is available */
2088         if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2089                 goto not_found;
2090         ini->is_smcd = true; /* prepare ISM check */
2091         ini->ism_peer_gid[0] = ntohll(pclc_smcd->ism.gid);
2092         rc = smc_find_ism_device(new_smc, ini);
2093         if (rc)
2094                 goto not_found;
2095         ini->ism_selected = 0;
2096         rc = smc_listen_ism_init(new_smc, ini);
2097         if (!rc)
2098                 return;         /* V1 ISM device found */
2099
2100 not_found:
2101         smc_find_ism_store_rc(rc, ini);
2102         ini->smcd_version &= ~SMC_V1;
2103         ini->ism_dev[0] = NULL;
2104         ini->is_smcd = false;
2105 }
2106
2107 /* listen worker: register buffers */
2108 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2109 {
2110         struct smc_connection *conn = &new_smc->conn;
2111
2112         if (!local_first) {
2113                 if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2114                         return SMC_CLC_DECL_ERR_REGRMB;
2115         }
2116         smc_rmb_sync_sg_for_device(&new_smc->conn);
2117
2118         return 0;
2119 }
2120
2121 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2122                                          struct smc_clc_msg_proposal *pclc,
2123                                          struct smc_init_info *ini)
2124 {
2125         struct smc_clc_v2_extension *smc_v2_ext;
2126         u8 smcr_version;
2127         int rc;
2128
2129         if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2130                 goto not_found;
2131
2132         smc_v2_ext = smc_get_clc_v2_ext(pclc);
2133         if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2134                 goto not_found;
2135
2136         /* prepare RDMA check */
2137         memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2138         memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2139         memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2140         ini->check_smcrv2 = true;
2141         ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2142         ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2143         ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2144         rc = smc_find_rdma_device(new_smc, ini);
2145         if (rc) {
2146                 smc_find_ism_store_rc(rc, ini);
2147                 goto not_found;
2148         }
2149         if (!ini->smcrv2.uses_gateway)
2150                 memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2151
2152         smcr_version = ini->smcr_version;
2153         ini->smcr_version = SMC_V2;
2154         rc = smc_listen_rdma_init(new_smc, ini);
2155         if (!rc)
2156                 rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2157         if (!rc)
2158                 return;
2159         ini->smcr_version = smcr_version;
2160         smc_find_ism_store_rc(rc, ini);
2161
2162 not_found:
2163         ini->smcr_version &= ~SMC_V2;
2164         ini->check_smcrv2 = false;
2165 }
2166
2167 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2168                                         struct smc_clc_msg_proposal *pclc,
2169                                         struct smc_init_info *ini)
2170 {
2171         int rc;
2172
2173         if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2174                 return SMC_CLC_DECL_NOSMCDEV;
2175
2176         /* prepare RDMA check */
2177         memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2178         memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2179         memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2180         rc = smc_find_rdma_device(new_smc, ini);
2181         if (rc) {
2182                 /* no RDMA device found */
2183                 return SMC_CLC_DECL_NOSMCDEV;
2184         }
2185         rc = smc_listen_rdma_init(new_smc, ini);
2186         if (rc)
2187                 return rc;
2188         return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2189 }
2190
2191 /* determine the local device matching to proposal */
2192 static int smc_listen_find_device(struct smc_sock *new_smc,
2193                                   struct smc_clc_msg_proposal *pclc,
2194                                   struct smc_init_info *ini)
2195 {
2196         int prfx_rc;
2197
2198         /* check for ISM device matching V2 proposed device */
2199         smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2200         if (ini->ism_dev[0])
2201                 return 0;
2202
2203         /* check for matching IP prefix and subnet length (V1) */
2204         prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2205         if (prfx_rc)
2206                 smc_find_ism_store_rc(prfx_rc, ini);
2207
2208         /* get vlan id from IP device */
2209         if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2210                 return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2211
2212         /* check for ISM device matching V1 proposed device */
2213         if (!prfx_rc)
2214                 smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2215         if (ini->ism_dev[0])
2216                 return 0;
2217
2218         if (!smcr_indicated(pclc->hdr.typev1) &&
2219             !smcr_indicated(pclc->hdr.typev2))
2220                 /* skip RDMA and decline */
2221                 return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2222
2223         /* check if RDMA V2 is available */
2224         smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2225         if (ini->smcrv2.ib_dev_v2)
2226                 return 0;
2227
2228         /* check if RDMA V1 is available */
2229         if (!prfx_rc) {
2230                 int rc;
2231
2232                 rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2233                 smc_find_ism_store_rc(rc, ini);
2234                 return (!rc) ? 0 : ini->rc;
2235         }
2236         return SMC_CLC_DECL_NOSMCDEV;
2237 }
2238
2239 /* listen worker: finish RDMA setup */
2240 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2241                                   struct smc_clc_msg_accept_confirm *cclc,
2242                                   bool local_first,
2243                                   struct smc_init_info *ini)
2244 {
2245         struct smc_link *link = new_smc->conn.lnk;
2246         int reason_code = 0;
2247
2248         if (local_first)
2249                 smc_link_save_peer_info(link, cclc, ini);
2250
2251         if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2252                 return SMC_CLC_DECL_ERR_RTOK;
2253
2254         if (local_first) {
2255                 if (smc_ib_ready_link(link))
2256                         return SMC_CLC_DECL_ERR_RDYLNK;
2257                 /* QP confirmation over RoCE fabric */
2258                 smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2259                 reason_code = smcr_serv_conf_first_link(new_smc);
2260                 smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2261         }
2262         return reason_code;
2263 }
2264
2265 /* setup for connection of server */
2266 static void smc_listen_work(struct work_struct *work)
2267 {
2268         struct smc_sock *new_smc = container_of(work, struct smc_sock,
2269                                                 smc_listen_work);
2270         struct socket *newclcsock = new_smc->clcsock;
2271         struct smc_clc_msg_accept_confirm *cclc;
2272         struct smc_clc_msg_proposal_area *buf;
2273         struct smc_clc_msg_proposal *pclc;
2274         struct smc_init_info *ini = NULL;
2275         u8 proposal_version = SMC_V1;
2276         u8 accept_version;
2277         int rc = 0;
2278
2279         if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2280                 return smc_listen_out_err(new_smc);
2281
2282         if (new_smc->use_fallback) {
2283                 smc_listen_out_connected(new_smc);
2284                 return;
2285         }
2286
2287         /* check if peer is smc capable */
2288         if (!tcp_sk(newclcsock->sk)->syn_smc) {
2289                 rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2290                 if (rc)
2291                         smc_listen_out_err(new_smc);
2292                 else
2293                         smc_listen_out_connected(new_smc);
2294                 return;
2295         }
2296
2297         /* do inband token exchange -
2298          * wait for and receive SMC Proposal CLC message
2299          */
2300         buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2301         if (!buf) {
2302                 rc = SMC_CLC_DECL_MEM;
2303                 goto out_decl;
2304         }
2305         pclc = (struct smc_clc_msg_proposal *)buf;
2306         rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2307                               SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2308         if (rc)
2309                 goto out_decl;
2310
2311         if (pclc->hdr.version > SMC_V1)
2312                 proposal_version = SMC_V2;
2313
2314         /* IPSec connections opt out of SMC optimizations */
2315         if (using_ipsec(new_smc)) {
2316                 rc = SMC_CLC_DECL_IPSEC;
2317                 goto out_decl;
2318         }
2319
2320         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2321         if (!ini) {
2322                 rc = SMC_CLC_DECL_MEM;
2323                 goto out_decl;
2324         }
2325
2326         /* initial version checking */
2327         rc = smc_listen_v2_check(new_smc, pclc, ini);
2328         if (rc)
2329                 goto out_decl;
2330
2331         mutex_lock(&smc_server_lgr_pending);
2332         smc_close_init(new_smc);
2333         smc_rx_init(new_smc);
2334         smc_tx_init(new_smc);
2335
2336         /* determine ISM or RoCE device used for connection */
2337         rc = smc_listen_find_device(new_smc, pclc, ini);
2338         if (rc)
2339                 goto out_unlock;
2340
2341         /* send SMC Accept CLC message */
2342         accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2343         rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2344                                  accept_version, ini->negotiated_eid);
2345         if (rc)
2346                 goto out_unlock;
2347
2348         /* SMC-D does not need this lock any more */
2349         if (ini->is_smcd)
2350                 mutex_unlock(&smc_server_lgr_pending);
2351
2352         /* receive SMC Confirm CLC message */
2353         memset(buf, 0, sizeof(*buf));
2354         cclc = (struct smc_clc_msg_accept_confirm *)buf;
2355         rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2356                               SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2357         if (rc) {
2358                 if (!ini->is_smcd)
2359                         goto out_unlock;
2360                 goto out_decl;
2361         }
2362
2363         /* finish worker */
2364         if (!ini->is_smcd) {
2365                 rc = smc_listen_rdma_finish(new_smc, cclc,
2366                                             ini->first_contact_local, ini);
2367                 if (rc)
2368                         goto out_unlock;
2369                 mutex_unlock(&smc_server_lgr_pending);
2370         }
2371         smc_conn_save_peer_info(new_smc, cclc);
2372         smc_listen_out_connected(new_smc);
2373         SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2374         goto out_free;
2375
2376 out_unlock:
2377         mutex_unlock(&smc_server_lgr_pending);
2378 out_decl:
2379         smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2380                            proposal_version);
2381 out_free:
2382         kfree(ini);
2383         kfree(buf);
2384 }
2385
2386 static void smc_tcp_listen_work(struct work_struct *work)
2387 {
2388         struct smc_sock *lsmc = container_of(work, struct smc_sock,
2389                                              tcp_listen_work);
2390         struct sock *lsk = &lsmc->sk;
2391         struct smc_sock *new_smc;
2392         int rc = 0;
2393
2394         lock_sock(lsk);
2395         while (lsk->sk_state == SMC_LISTEN) {
2396                 rc = smc_clcsock_accept(lsmc, &new_smc);
2397                 if (rc) /* clcsock accept queue empty or error */
2398                         goto out;
2399                 if (!new_smc)
2400                         continue;
2401
2402                 if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2403                         atomic_inc(&lsmc->queued_smc_hs);
2404
2405                 new_smc->listen_smc = lsmc;
2406                 new_smc->use_fallback = lsmc->use_fallback;
2407                 new_smc->fallback_rsn = lsmc->fallback_rsn;
2408                 sock_hold(lsk); /* sock_put in smc_listen_work */
2409                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2410                 smc_copy_sock_settings_to_smc(new_smc);
2411                 new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
2412                 new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
2413                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
2414                 if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2415                         sock_put(&new_smc->sk);
2416         }
2417
2418 out:
2419         release_sock(lsk);
2420         sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2421 }
2422
2423 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2424 {
2425         struct smc_sock *lsmc;
2426
2427         read_lock_bh(&listen_clcsock->sk_callback_lock);
2428         lsmc = smc_clcsock_user_data(listen_clcsock);
2429         if (!lsmc)
2430                 goto out;
2431         lsmc->clcsk_data_ready(listen_clcsock);
2432         if (lsmc->sk.sk_state == SMC_LISTEN) {
2433                 sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2434                 if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2435                         sock_put(&lsmc->sk);
2436         }
2437 out:
2438         read_unlock_bh(&listen_clcsock->sk_callback_lock);
2439 }
2440
2441 static int smc_listen(struct socket *sock, int backlog)
2442 {
2443         struct sock *sk = sock->sk;
2444         struct smc_sock *smc;
2445         int rc;
2446
2447         smc = smc_sk(sk);
2448         lock_sock(sk);
2449
2450         rc = -EINVAL;
2451         if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2452             smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2453                 goto out;
2454
2455         rc = 0;
2456         if (sk->sk_state == SMC_LISTEN) {
2457                 sk->sk_max_ack_backlog = backlog;
2458                 goto out;
2459         }
2460         /* some socket options are handled in core, so we could not apply
2461          * them to the clc socket -- copy smc socket options to clc socket
2462          */
2463         smc_copy_sock_settings_to_clc(smc);
2464         if (!smc->use_fallback)
2465                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2466
2467         /* save original sk_data_ready function and establish
2468          * smc-specific sk_data_ready function
2469          */
2470         write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2471         smc->clcsock->sk->sk_user_data =
2472                 (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2473         smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2474                                smc_clcsock_data_ready, &smc->clcsk_data_ready);
2475         write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2476
2477         /* save original ops */
2478         smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2479
2480         smc->af_ops = *smc->ori_af_ops;
2481         smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2482
2483         inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2484
2485         if (smc->limit_smc_hs)
2486                 tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2487
2488         rc = kernel_listen(smc->clcsock, backlog);
2489         if (rc) {
2490                 write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2491                 smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2492                                        &smc->clcsk_data_ready);
2493                 smc->clcsock->sk->sk_user_data = NULL;
2494                 write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2495                 goto out;
2496         }
2497         sk->sk_max_ack_backlog = backlog;
2498         sk->sk_ack_backlog = 0;
2499         sk->sk_state = SMC_LISTEN;
2500
2501 out:
2502         release_sock(sk);
2503         return rc;
2504 }
2505
2506 static int smc_accept(struct socket *sock, struct socket *new_sock,
2507                       int flags, bool kern)
2508 {
2509         struct sock *sk = sock->sk, *nsk;
2510         DECLARE_WAITQUEUE(wait, current);
2511         struct smc_sock *lsmc;
2512         long timeo;
2513         int rc = 0;
2514
2515         lsmc = smc_sk(sk);
2516         sock_hold(sk); /* sock_put below */
2517         lock_sock(sk);
2518
2519         if (lsmc->sk.sk_state != SMC_LISTEN) {
2520                 rc = -EINVAL;
2521                 release_sock(sk);
2522                 goto out;
2523         }
2524
2525         /* Wait for an incoming connection */
2526         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2527         add_wait_queue_exclusive(sk_sleep(sk), &wait);
2528         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2529                 set_current_state(TASK_INTERRUPTIBLE);
2530                 if (!timeo) {
2531                         rc = -EAGAIN;
2532                         break;
2533                 }
2534                 release_sock(sk);
2535                 timeo = schedule_timeout(timeo);
2536                 /* wakeup by sk_data_ready in smc_listen_work() */
2537                 sched_annotate_sleep();
2538                 lock_sock(sk);
2539                 if (signal_pending(current)) {
2540                         rc = sock_intr_errno(timeo);
2541                         break;
2542                 }
2543         }
2544         set_current_state(TASK_RUNNING);
2545         remove_wait_queue(sk_sleep(sk), &wait);
2546
2547         if (!rc)
2548                 rc = sock_error(nsk);
2549         release_sock(sk);
2550         if (rc)
2551                 goto out;
2552
2553         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
2554                 /* wait till data arrives on the socket */
2555                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2556                                                                 MSEC_PER_SEC);
2557                 if (smc_sk(nsk)->use_fallback) {
2558                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2559
2560                         lock_sock(clcsk);
2561                         if (skb_queue_empty(&clcsk->sk_receive_queue))
2562                                 sk_wait_data(clcsk, &timeo, NULL);
2563                         release_sock(clcsk);
2564                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2565                         lock_sock(nsk);
2566                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2567                         release_sock(nsk);
2568                 }
2569         }
2570
2571 out:
2572         sock_put(sk); /* sock_hold above */
2573         return rc;
2574 }
2575
2576 static int smc_getname(struct socket *sock, struct sockaddr *addr,
2577                        int peer)
2578 {
2579         struct smc_sock *smc;
2580
2581         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2582             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2583                 return -ENOTCONN;
2584
2585         smc = smc_sk(sock->sk);
2586
2587         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2588 }
2589
2590 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2591 {
2592         struct sock *sk = sock->sk;
2593         struct smc_sock *smc;
2594         int rc = -EPIPE;
2595
2596         smc = smc_sk(sk);
2597         lock_sock(sk);
2598         if ((sk->sk_state != SMC_ACTIVE) &&
2599             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2600             (sk->sk_state != SMC_INIT))
2601                 goto out;
2602
2603         if (msg->msg_flags & MSG_FASTOPEN) {
2604                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2605                         rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2606                         if (rc)
2607                                 goto out;
2608                 } else {
2609                         rc = -EINVAL;
2610                         goto out;
2611                 }
2612         }
2613
2614         if (smc->use_fallback) {
2615                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2616         } else {
2617                 rc = smc_tx_sendmsg(smc, msg, len);
2618                 SMC_STAT_TX_PAYLOAD(smc, len, rc);
2619         }
2620 out:
2621         release_sock(sk);
2622         return rc;
2623 }
2624
2625 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2626                        int flags)
2627 {
2628         struct sock *sk = sock->sk;
2629         struct smc_sock *smc;
2630         int rc = -ENOTCONN;
2631
2632         smc = smc_sk(sk);
2633         lock_sock(sk);
2634         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2635                 /* socket was connected before, no more data to read */
2636                 rc = 0;
2637                 goto out;
2638         }
2639         if ((sk->sk_state == SMC_INIT) ||
2640             (sk->sk_state == SMC_LISTEN) ||
2641             (sk->sk_state == SMC_CLOSED))
2642                 goto out;
2643
2644         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2645                 rc = 0;
2646                 goto out;
2647         }
2648
2649         if (smc->use_fallback) {
2650                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2651         } else {
2652                 msg->msg_namelen = 0;
2653                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2654                 SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2655         }
2656
2657 out:
2658         release_sock(sk);
2659         return rc;
2660 }
2661
2662 static __poll_t smc_accept_poll(struct sock *parent)
2663 {
2664         struct smc_sock *isk = smc_sk(parent);
2665         __poll_t mask = 0;
2666
2667         spin_lock(&isk->accept_q_lock);
2668         if (!list_empty(&isk->accept_q))
2669                 mask = EPOLLIN | EPOLLRDNORM;
2670         spin_unlock(&isk->accept_q_lock);
2671
2672         return mask;
2673 }
2674
2675 static __poll_t smc_poll(struct file *file, struct socket *sock,
2676                              poll_table *wait)
2677 {
2678         struct sock *sk = sock->sk;
2679         struct smc_sock *smc;
2680         __poll_t mask = 0;
2681
2682         if (!sk)
2683                 return EPOLLNVAL;
2684
2685         smc = smc_sk(sock->sk);
2686         if (smc->use_fallback) {
2687                 /* delegate to CLC child sock */
2688                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2689                 sk->sk_err = smc->clcsock->sk->sk_err;
2690         } else {
2691                 if (sk->sk_state != SMC_CLOSED)
2692                         sock_poll_wait(file, sock, wait);
2693                 if (sk->sk_err)
2694                         mask |= EPOLLERR;
2695                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2696                     (sk->sk_state == SMC_CLOSED))
2697                         mask |= EPOLLHUP;
2698                 if (sk->sk_state == SMC_LISTEN) {
2699                         /* woken up by sk_data_ready in smc_listen_work() */
2700                         mask |= smc_accept_poll(sk);
2701                 } else if (smc->use_fallback) { /* as result of connect_work()*/
2702                         mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2703                                                            wait);
2704                         sk->sk_err = smc->clcsock->sk->sk_err;
2705                 } else {
2706                         if ((sk->sk_state != SMC_INIT &&
2707                              atomic_read(&smc->conn.sndbuf_space)) ||
2708                             sk->sk_shutdown & SEND_SHUTDOWN) {
2709                                 mask |= EPOLLOUT | EPOLLWRNORM;
2710                         } else {
2711                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2712                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2713                         }
2714                         if (atomic_read(&smc->conn.bytes_to_rcv))
2715                                 mask |= EPOLLIN | EPOLLRDNORM;
2716                         if (sk->sk_shutdown & RCV_SHUTDOWN)
2717                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2718                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
2719                                 mask |= EPOLLIN;
2720                         if (smc->conn.urg_state == SMC_URG_VALID)
2721                                 mask |= EPOLLPRI;
2722                 }
2723         }
2724
2725         return mask;
2726 }
2727
2728 static int smc_shutdown(struct socket *sock, int how)
2729 {
2730         struct sock *sk = sock->sk;
2731         bool do_shutdown = true;
2732         struct smc_sock *smc;
2733         int rc = -EINVAL;
2734         int old_state;
2735         int rc1 = 0;
2736
2737         smc = smc_sk(sk);
2738
2739         if ((how < SHUT_RD) || (how > SHUT_RDWR))
2740                 return rc;
2741
2742         lock_sock(sk);
2743
2744         if (sock->state == SS_CONNECTING) {
2745                 if (sk->sk_state == SMC_ACTIVE)
2746                         sock->state = SS_CONNECTED;
2747                 else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2748                          sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2749                          sk->sk_state == SMC_APPCLOSEWAIT1 ||
2750                          sk->sk_state == SMC_APPCLOSEWAIT2 ||
2751                          sk->sk_state == SMC_APPFINCLOSEWAIT)
2752                         sock->state = SS_DISCONNECTING;
2753         }
2754
2755         rc = -ENOTCONN;
2756         if ((sk->sk_state != SMC_ACTIVE) &&
2757             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2758             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2759             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2760             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2761             (sk->sk_state != SMC_APPFINCLOSEWAIT))
2762                 goto out;
2763         if (smc->use_fallback) {
2764                 rc = kernel_sock_shutdown(smc->clcsock, how);
2765                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2766                 if (sk->sk_shutdown == SHUTDOWN_MASK) {
2767                         sk->sk_state = SMC_CLOSED;
2768                         sk->sk_socket->state = SS_UNCONNECTED;
2769                         sock_put(sk);
2770                 }
2771                 goto out;
2772         }
2773         switch (how) {
2774         case SHUT_RDWR:         /* shutdown in both directions */
2775                 old_state = sk->sk_state;
2776                 rc = smc_close_active(smc);
2777                 if (old_state == SMC_ACTIVE &&
2778                     sk->sk_state == SMC_PEERCLOSEWAIT1)
2779                         do_shutdown = false;
2780                 break;
2781         case SHUT_WR:
2782                 rc = smc_close_shutdown_write(smc);
2783                 break;
2784         case SHUT_RD:
2785                 rc = 0;
2786                 /* nothing more to do because peer is not involved */
2787                 break;
2788         }
2789         if (do_shutdown && smc->clcsock)
2790                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
2791         /* map sock_shutdown_cmd constants to sk_shutdown value range */
2792         sk->sk_shutdown |= how + 1;
2793
2794         if (sk->sk_state == SMC_CLOSED)
2795                 sock->state = SS_UNCONNECTED;
2796         else
2797                 sock->state = SS_DISCONNECTING;
2798 out:
2799         release_sock(sk);
2800         return rc ? rc : rc1;
2801 }
2802
2803 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2804                             char __user *optval, int __user *optlen)
2805 {
2806         struct smc_sock *smc;
2807         int val, len;
2808
2809         smc = smc_sk(sock->sk);
2810
2811         if (get_user(len, optlen))
2812                 return -EFAULT;
2813
2814         len = min_t(int, len, sizeof(int));
2815
2816         if (len < 0)
2817                 return -EINVAL;
2818
2819         switch (optname) {
2820         case SMC_LIMIT_HS:
2821                 val = smc->limit_smc_hs;
2822                 break;
2823         default:
2824                 return -EOPNOTSUPP;
2825         }
2826
2827         if (put_user(len, optlen))
2828                 return -EFAULT;
2829         if (copy_to_user(optval, &val, len))
2830                 return -EFAULT;
2831
2832         return 0;
2833 }
2834
2835 static int __smc_setsockopt(struct socket *sock, int level, int optname,
2836                             sockptr_t optval, unsigned int optlen)
2837 {
2838         struct sock *sk = sock->sk;
2839         struct smc_sock *smc;
2840         int val, rc;
2841
2842         smc = smc_sk(sk);
2843
2844         lock_sock(sk);
2845         switch (optname) {
2846         case SMC_LIMIT_HS:
2847                 if (optlen < sizeof(int)) {
2848                         rc = -EINVAL;
2849                         break;
2850                 }
2851                 if (copy_from_sockptr(&val, optval, sizeof(int))) {
2852                         rc = -EFAULT;
2853                         break;
2854                 }
2855
2856                 smc->limit_smc_hs = !!val;
2857                 rc = 0;
2858                 break;
2859         default:
2860                 rc = -EOPNOTSUPP;
2861                 break;
2862         }
2863         release_sock(sk);
2864
2865         return rc;
2866 }
2867
2868 static int smc_setsockopt(struct socket *sock, int level, int optname,
2869                           sockptr_t optval, unsigned int optlen)
2870 {
2871         struct sock *sk = sock->sk;
2872         struct smc_sock *smc;
2873         int val, rc;
2874
2875         if (level == SOL_TCP && optname == TCP_ULP)
2876                 return -EOPNOTSUPP;
2877         else if (level == SOL_SMC)
2878                 return __smc_setsockopt(sock, level, optname, optval, optlen);
2879
2880         smc = smc_sk(sk);
2881
2882         /* generic setsockopts reaching us here always apply to the
2883          * CLC socket
2884          */
2885         mutex_lock(&smc->clcsock_release_lock);
2886         if (!smc->clcsock) {
2887                 mutex_unlock(&smc->clcsock_release_lock);
2888                 return -EBADF;
2889         }
2890         if (unlikely(!smc->clcsock->ops->setsockopt))
2891                 rc = -EOPNOTSUPP;
2892         else
2893                 rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
2894                                                    optval, optlen);
2895         if (smc->clcsock->sk->sk_err) {
2896                 sk->sk_err = smc->clcsock->sk->sk_err;
2897                 sk_error_report(sk);
2898         }
2899         mutex_unlock(&smc->clcsock_release_lock);
2900
2901         if (optlen < sizeof(int))
2902                 return -EINVAL;
2903         if (copy_from_sockptr(&val, optval, sizeof(int)))
2904                 return -EFAULT;
2905
2906         lock_sock(sk);
2907         if (rc || smc->use_fallback)
2908                 goto out;
2909         switch (optname) {
2910         case TCP_FASTOPEN:
2911         case TCP_FASTOPEN_CONNECT:
2912         case TCP_FASTOPEN_KEY:
2913         case TCP_FASTOPEN_NO_COOKIE:
2914                 /* option not supported by SMC */
2915                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2916                         rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2917                 } else {
2918                         rc = -EINVAL;
2919                 }
2920                 break;
2921         case TCP_NODELAY:
2922                 if (sk->sk_state != SMC_INIT &&
2923                     sk->sk_state != SMC_LISTEN &&
2924                     sk->sk_state != SMC_CLOSED) {
2925                         if (val) {
2926                                 SMC_STAT_INC(smc, ndly_cnt);
2927                                 smc_tx_pending(&smc->conn);
2928                                 cancel_delayed_work(&smc->conn.tx_work);
2929                         }
2930                 }
2931                 break;
2932         case TCP_CORK:
2933                 if (sk->sk_state != SMC_INIT &&
2934                     sk->sk_state != SMC_LISTEN &&
2935                     sk->sk_state != SMC_CLOSED) {
2936                         if (!val) {
2937                                 SMC_STAT_INC(smc, cork_cnt);
2938                                 smc_tx_pending(&smc->conn);
2939                                 cancel_delayed_work(&smc->conn.tx_work);
2940                         }
2941                 }
2942                 break;
2943         case TCP_DEFER_ACCEPT:
2944                 smc->sockopt_defer_accept = val;
2945                 break;
2946         default:
2947                 break;
2948         }
2949 out:
2950         release_sock(sk);
2951
2952         return rc;
2953 }
2954
2955 static int smc_getsockopt(struct socket *sock, int level, int optname,
2956                           char __user *optval, int __user *optlen)
2957 {
2958         struct smc_sock *smc;
2959         int rc;
2960
2961         if (level == SOL_SMC)
2962                 return __smc_getsockopt(sock, level, optname, optval, optlen);
2963
2964         smc = smc_sk(sock->sk);
2965         mutex_lock(&smc->clcsock_release_lock);
2966         if (!smc->clcsock) {
2967                 mutex_unlock(&smc->clcsock_release_lock);
2968                 return -EBADF;
2969         }
2970         /* socket options apply to the CLC socket */
2971         if (unlikely(!smc->clcsock->ops->getsockopt)) {
2972                 mutex_unlock(&smc->clcsock_release_lock);
2973                 return -EOPNOTSUPP;
2974         }
2975         rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
2976                                            optval, optlen);
2977         mutex_unlock(&smc->clcsock_release_lock);
2978         return rc;
2979 }
2980
2981 static int smc_ioctl(struct socket *sock, unsigned int cmd,
2982                      unsigned long arg)
2983 {
2984         union smc_host_cursor cons, urg;
2985         struct smc_connection *conn;
2986         struct smc_sock *smc;
2987         int answ;
2988
2989         smc = smc_sk(sock->sk);
2990         conn = &smc->conn;
2991         lock_sock(&smc->sk);
2992         if (smc->use_fallback) {
2993                 if (!smc->clcsock) {
2994                         release_sock(&smc->sk);
2995                         return -EBADF;
2996                 }
2997                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
2998                 release_sock(&smc->sk);
2999                 return answ;
3000         }
3001         switch (cmd) {
3002         case SIOCINQ: /* same as FIONREAD */
3003                 if (smc->sk.sk_state == SMC_LISTEN) {
3004                         release_sock(&smc->sk);
3005                         return -EINVAL;
3006                 }
3007                 if (smc->sk.sk_state == SMC_INIT ||
3008                     smc->sk.sk_state == SMC_CLOSED)
3009                         answ = 0;
3010                 else
3011                         answ = atomic_read(&smc->conn.bytes_to_rcv);
3012                 break;
3013         case SIOCOUTQ:
3014                 /* output queue size (not send + not acked) */
3015                 if (smc->sk.sk_state == SMC_LISTEN) {
3016                         release_sock(&smc->sk);
3017                         return -EINVAL;
3018                 }
3019                 if (smc->sk.sk_state == SMC_INIT ||
3020                     smc->sk.sk_state == SMC_CLOSED)
3021                         answ = 0;
3022                 else
3023                         answ = smc->conn.sndbuf_desc->len -
3024                                         atomic_read(&smc->conn.sndbuf_space);
3025                 break;
3026         case SIOCOUTQNSD:
3027                 /* output queue size (not send only) */
3028                 if (smc->sk.sk_state == SMC_LISTEN) {
3029                         release_sock(&smc->sk);
3030                         return -EINVAL;
3031                 }
3032                 if (smc->sk.sk_state == SMC_INIT ||
3033                     smc->sk.sk_state == SMC_CLOSED)
3034                         answ = 0;
3035                 else
3036                         answ = smc_tx_prepared_sends(&smc->conn);
3037                 break;
3038         case SIOCATMARK:
3039                 if (smc->sk.sk_state == SMC_LISTEN) {
3040                         release_sock(&smc->sk);
3041                         return -EINVAL;
3042                 }
3043                 if (smc->sk.sk_state == SMC_INIT ||
3044                     smc->sk.sk_state == SMC_CLOSED) {
3045                         answ = 0;
3046                 } else {
3047                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3048                         smc_curs_copy(&urg, &conn->urg_curs, conn);
3049                         answ = smc_curs_diff(conn->rmb_desc->len,
3050                                              &cons, &urg) == 1;
3051                 }
3052                 break;
3053         default:
3054                 release_sock(&smc->sk);
3055                 return -ENOIOCTLCMD;
3056         }
3057         release_sock(&smc->sk);
3058
3059         return put_user(answ, (int __user *)arg);
3060 }
3061
3062 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
3063                             int offset, size_t size, int flags)
3064 {
3065         struct sock *sk = sock->sk;
3066         struct smc_sock *smc;
3067         int rc = -EPIPE;
3068
3069         smc = smc_sk(sk);
3070         lock_sock(sk);
3071         if (sk->sk_state != SMC_ACTIVE) {
3072                 release_sock(sk);
3073                 goto out;
3074         }
3075         release_sock(sk);
3076         if (smc->use_fallback) {
3077                 rc = kernel_sendpage(smc->clcsock, page, offset,
3078                                      size, flags);
3079         } else {
3080                 lock_sock(sk);
3081                 rc = smc_tx_sendpage(smc, page, offset, size, flags);
3082                 release_sock(sk);
3083                 SMC_STAT_INC(smc, sendpage_cnt);
3084         }
3085
3086 out:
3087         return rc;
3088 }
3089
3090 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3091  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3092  * updates till whenever a respective page has been fully processed.
3093  * Note that subsequent recv() calls have to wait till all splice() processing
3094  * completed.
3095  */
3096 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3097                                struct pipe_inode_info *pipe, size_t len,
3098                                unsigned int flags)
3099 {
3100         struct sock *sk = sock->sk;
3101         struct smc_sock *smc;
3102         int rc = -ENOTCONN;
3103
3104         smc = smc_sk(sk);
3105         lock_sock(sk);
3106         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3107                 /* socket was connected before, no more data to read */
3108                 rc = 0;
3109                 goto out;
3110         }
3111         if (sk->sk_state == SMC_INIT ||
3112             sk->sk_state == SMC_LISTEN ||
3113             sk->sk_state == SMC_CLOSED)
3114                 goto out;
3115
3116         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3117                 rc = 0;
3118                 goto out;
3119         }
3120
3121         if (smc->use_fallback) {
3122                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3123                                                     pipe, len, flags);
3124         } else {
3125                 if (*ppos) {
3126                         rc = -ESPIPE;
3127                         goto out;
3128                 }
3129                 if (flags & SPLICE_F_NONBLOCK)
3130                         flags = MSG_DONTWAIT;
3131                 else
3132                         flags = 0;
3133                 SMC_STAT_INC(smc, splice_cnt);
3134                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3135         }
3136 out:
3137         release_sock(sk);
3138
3139         return rc;
3140 }
3141
3142 /* must look like tcp */
3143 static const struct proto_ops smc_sock_ops = {
3144         .family         = PF_SMC,
3145         .owner          = THIS_MODULE,
3146         .release        = smc_release,
3147         .bind           = smc_bind,
3148         .connect        = smc_connect,
3149         .socketpair     = sock_no_socketpair,
3150         .accept         = smc_accept,
3151         .getname        = smc_getname,
3152         .poll           = smc_poll,
3153         .ioctl          = smc_ioctl,
3154         .listen         = smc_listen,
3155         .shutdown       = smc_shutdown,
3156         .setsockopt     = smc_setsockopt,
3157         .getsockopt     = smc_getsockopt,
3158         .sendmsg        = smc_sendmsg,
3159         .recvmsg        = smc_recvmsg,
3160         .mmap           = sock_no_mmap,
3161         .sendpage       = smc_sendpage,
3162         .splice_read    = smc_splice_read,
3163 };
3164
3165 static int __smc_create(struct net *net, struct socket *sock, int protocol,
3166                         int kern, struct socket *clcsock)
3167 {
3168         int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3169         struct smc_sock *smc;
3170         struct sock *sk;
3171         int rc;
3172
3173         rc = -ESOCKTNOSUPPORT;
3174         if (sock->type != SOCK_STREAM)
3175                 goto out;
3176
3177         rc = -EPROTONOSUPPORT;
3178         if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3179                 goto out;
3180
3181         rc = -ENOBUFS;
3182         sock->ops = &smc_sock_ops;
3183         sock->state = SS_UNCONNECTED;
3184         sk = smc_sock_alloc(net, sock, protocol);
3185         if (!sk)
3186                 goto out;
3187
3188         /* create internal TCP socket for CLC handshake and fallback */
3189         smc = smc_sk(sk);
3190         smc->use_fallback = false; /* assume rdma capability first */
3191         smc->fallback_rsn = 0;
3192
3193         /* default behavior from limit_smc_hs in every net namespace */
3194         smc->limit_smc_hs = net->smc.limit_smc_hs;
3195
3196         rc = 0;
3197         if (!clcsock) {
3198                 rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3199                                       &smc->clcsock);
3200                 if (rc) {
3201                         sk_common_release(sk);
3202                         goto out;
3203                 }
3204         } else {
3205                 smc->clcsock = clcsock;
3206         }
3207
3208         smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);
3209         smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);
3210
3211 out:
3212         return rc;
3213 }
3214
3215 static int smc_create(struct net *net, struct socket *sock, int protocol,
3216                       int kern)
3217 {
3218         return __smc_create(net, sock, protocol, kern, NULL);
3219 }
3220
3221 static const struct net_proto_family smc_sock_family_ops = {
3222         .family = PF_SMC,
3223         .owner  = THIS_MODULE,
3224         .create = smc_create,
3225 };
3226
3227 static int smc_ulp_init(struct sock *sk)
3228 {
3229         struct socket *tcp = sk->sk_socket;
3230         struct net *net = sock_net(sk);
3231         struct socket *smcsock;
3232         int protocol, ret;
3233
3234         /* only TCP can be replaced */
3235         if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3236             (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3237                 return -ESOCKTNOSUPPORT;
3238         /* don't handle wq now */
3239         if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3240                 return -ENOTCONN;
3241
3242         if (sk->sk_family == AF_INET)
3243                 protocol = SMCPROTO_SMC;
3244         else
3245                 protocol = SMCPROTO_SMC6;
3246
3247         smcsock = sock_alloc();
3248         if (!smcsock)
3249                 return -ENFILE;
3250
3251         smcsock->type = SOCK_STREAM;
3252         __module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3253         ret = __smc_create(net, smcsock, protocol, 1, tcp);
3254         if (ret) {
3255                 sock_release(smcsock); /* module_put() which ops won't be NULL */
3256                 return ret;
3257         }
3258
3259         /* replace tcp socket to smc */
3260         smcsock->file = tcp->file;
3261         smcsock->file->private_data = smcsock;
3262         smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3263         smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3264         tcp->file = NULL;
3265
3266         return ret;
3267 }
3268
3269 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3270                           const gfp_t priority)
3271 {
3272         struct inet_connection_sock *icsk = inet_csk(newsk);
3273
3274         /* don't inherit ulp ops to child when listen */
3275         icsk->icsk_ulp_ops = NULL;
3276 }
3277
3278 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3279         .name           = "smc",
3280         .owner          = THIS_MODULE,
3281         .init           = smc_ulp_init,
3282         .clone          = smc_ulp_clone,
3283 };
3284
3285 unsigned int smc_net_id;
3286
3287 static __net_init int smc_net_init(struct net *net)
3288 {
3289         int rc;
3290
3291         rc = smc_sysctl_net_init(net);
3292         if (rc)
3293                 return rc;
3294         return smc_pnet_net_init(net);
3295 }
3296
3297 static void __net_exit smc_net_exit(struct net *net)
3298 {
3299         smc_sysctl_net_exit(net);
3300         smc_pnet_net_exit(net);
3301 }
3302
3303 static __net_init int smc_net_stat_init(struct net *net)
3304 {
3305         return smc_stats_init(net);
3306 }
3307
3308 static void __net_exit smc_net_stat_exit(struct net *net)
3309 {
3310         smc_stats_exit(net);
3311 }
3312
3313 static struct pernet_operations smc_net_ops = {
3314         .init = smc_net_init,
3315         .exit = smc_net_exit,
3316         .id   = &smc_net_id,
3317         .size = sizeof(struct smc_net),
3318 };
3319
3320 static struct pernet_operations smc_net_stat_ops = {
3321         .init = smc_net_stat_init,
3322         .exit = smc_net_stat_exit,
3323 };
3324
3325 static int __init smc_init(void)
3326 {
3327         int rc;
3328
3329         rc = register_pernet_subsys(&smc_net_ops);
3330         if (rc)
3331                 return rc;
3332
3333         rc = register_pernet_subsys(&smc_net_stat_ops);
3334         if (rc)
3335                 return rc;
3336
3337         smc_ism_init();
3338         smc_clc_init();
3339
3340         rc = smc_nl_init();
3341         if (rc)
3342                 goto out_pernet_subsys;
3343
3344         rc = smc_pnet_init();
3345         if (rc)
3346                 goto out_nl;
3347
3348         rc = -ENOMEM;
3349
3350         smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3351         if (!smc_tcp_ls_wq)
3352                 goto out_pnet;
3353
3354         smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3355         if (!smc_hs_wq)
3356                 goto out_alloc_tcp_ls_wq;
3357
3358         smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3359         if (!smc_close_wq)
3360                 goto out_alloc_hs_wq;
3361
3362         rc = smc_core_init();
3363         if (rc) {
3364                 pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3365                 goto out_alloc_wqs;
3366         }
3367
3368         rc = smc_llc_init();
3369         if (rc) {
3370                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3371                 goto out_core;
3372         }
3373
3374         rc = smc_cdc_init();
3375         if (rc) {
3376                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3377                 goto out_core;
3378         }
3379
3380         rc = proto_register(&smc_proto, 1);
3381         if (rc) {
3382                 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3383                 goto out_core;
3384         }
3385
3386         rc = proto_register(&smc_proto6, 1);
3387         if (rc) {
3388                 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3389                 goto out_proto;
3390         }
3391
3392         rc = sock_register(&smc_sock_family_ops);
3393         if (rc) {
3394                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
3395                 goto out_proto6;
3396         }
3397         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3398         INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3399
3400         rc = smc_ib_register_client();
3401         if (rc) {
3402                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
3403                 goto out_sock;
3404         }
3405
3406         rc = tcp_register_ulp(&smc_ulp_ops);
3407         if (rc) {
3408                 pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3409                 goto out_ib;
3410         }
3411
3412         static_branch_enable(&tcp_have_smc);
3413         return 0;
3414
3415 out_ib:
3416         smc_ib_unregister_client();
3417 out_sock:
3418         sock_unregister(PF_SMC);
3419 out_proto6:
3420         proto_unregister(&smc_proto6);
3421 out_proto:
3422         proto_unregister(&smc_proto);
3423 out_core:
3424         smc_core_exit();
3425 out_alloc_wqs:
3426         destroy_workqueue(smc_close_wq);
3427 out_alloc_hs_wq:
3428         destroy_workqueue(smc_hs_wq);
3429 out_alloc_tcp_ls_wq:
3430         destroy_workqueue(smc_tcp_ls_wq);
3431 out_pnet:
3432         smc_pnet_exit();
3433 out_nl:
3434         smc_nl_exit();
3435 out_pernet_subsys:
3436         unregister_pernet_subsys(&smc_net_ops);
3437
3438         return rc;
3439 }
3440
3441 static void __exit smc_exit(void)
3442 {
3443         static_branch_disable(&tcp_have_smc);
3444         tcp_unregister_ulp(&smc_ulp_ops);
3445         sock_unregister(PF_SMC);
3446         smc_core_exit();
3447         smc_ib_unregister_client();
3448         destroy_workqueue(smc_close_wq);
3449         destroy_workqueue(smc_tcp_ls_wq);
3450         destroy_workqueue(smc_hs_wq);
3451         proto_unregister(&smc_proto6);
3452         proto_unregister(&smc_proto);
3453         smc_pnet_exit();
3454         smc_nl_exit();
3455         smc_clc_exit();
3456         unregister_pernet_subsys(&smc_net_stat_ops);
3457         unregister_pernet_subsys(&smc_net_ops);
3458         rcu_barrier();
3459 }
3460
3461 module_init(smc_init);
3462 module_exit(smc_exit);
3463
3464 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3465 MODULE_DESCRIPTION("smc socket address family");
3466 MODULE_LICENSE("GPL");
3467 MODULE_ALIAS_NETPROTO(PF_SMC);
3468 MODULE_ALIAS_TCP_ULP("smc");