xref: /linux/net/smc/af_smc.c (revision 08df80a3c51674ab73ae770885a383ca553fbbbf)
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 #include <linux/splice.h>
31 
32 #include <net/sock.h>
33 #include <net/tcp.h>
34 #include <net/smc.h>
35 #include <asm/ioctls.h>
36 
37 #include <net/net_namespace.h>
38 #include <net/netns/generic.h>
39 #include "smc_netns.h"
40 
41 #include "smc.h"
42 #include "smc_clc.h"
43 #include "smc_llc.h"
44 #include "smc_cdc.h"
45 #include "smc_core.h"
46 #include "smc_ib.h"
47 #include "smc_ism.h"
48 #include "smc_pnet.h"
49 #include "smc_netlink.h"
50 #include "smc_tx.h"
51 #include "smc_rx.h"
52 #include "smc_close.h"
53 #include "smc_stats.h"
54 #include "smc_tracepoint.h"
55 #include "smc_sysctl.h"
56 
57 static DEFINE_MUTEX(smc_server_lgr_pending);	/* serialize link group
58 						 * creation on server
59 						 */
60 static DEFINE_MUTEX(smc_client_lgr_pending);	/* serialize link group
61 						 * creation on client
62 						 */
63 
64 static struct workqueue_struct	*smc_tcp_ls_wq;	/* wq for tcp listen work */
65 struct workqueue_struct	*smc_hs_wq;	/* wq for handshake work */
66 struct workqueue_struct	*smc_close_wq;	/* wq for close work */
67 
68 static void smc_tcp_listen_work(struct work_struct *);
69 static void smc_connect_work(struct work_struct *);
70 
71 int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb)
72 {
73 	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
74 	void *hdr;
75 
76 	if (cb_ctx->pos[0])
77 		goto out;
78 
79 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
80 			  &smc_gen_nl_family, NLM_F_MULTI,
81 			  SMC_NETLINK_DUMP_HS_LIMITATION);
82 	if (!hdr)
83 		return -ENOMEM;
84 
85 	if (nla_put_u8(skb, SMC_NLA_HS_LIMITATION_ENABLED,
86 		       sock_net(skb->sk)->smc.limit_smc_hs))
87 		goto err;
88 
89 	genlmsg_end(skb, hdr);
90 	cb_ctx->pos[0] = 1;
91 out:
92 	return skb->len;
93 err:
94 	genlmsg_cancel(skb, hdr);
95 	return -EMSGSIZE;
96 }
97 
98 int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
99 {
100 	sock_net(skb->sk)->smc.limit_smc_hs = true;
101 	return 0;
102 }
103 
104 int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
105 {
106 	sock_net(skb->sk)->smc.limit_smc_hs = false;
107 	return 0;
108 }
109 
110 static void smc_set_keepalive(struct sock *sk, int val)
111 {
112 	struct smc_sock *smc = smc_sk(sk);
113 
114 	smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
115 }
116 
117 static struct sock *smc_tcp_syn_recv_sock(const struct sock *sk,
118 					  struct sk_buff *skb,
119 					  struct request_sock *req,
120 					  struct dst_entry *dst,
121 					  struct request_sock *req_unhash,
122 					  bool *own_req)
123 {
124 	struct smc_sock *smc;
125 	struct sock *child;
126 
127 	smc = smc_clcsock_user_data(sk);
128 
129 	if (READ_ONCE(sk->sk_ack_backlog) + atomic_read(&smc->queued_smc_hs) >
130 				sk->sk_max_ack_backlog)
131 		goto drop;
132 
133 	if (sk_acceptq_is_full(&smc->sk)) {
134 		NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
135 		goto drop;
136 	}
137 
138 	/* passthrough to original syn recv sock fct */
139 	child = smc->ori_af_ops->syn_recv_sock(sk, skb, req, dst, req_unhash,
140 					       own_req);
141 	/* child must not inherit smc or its ops */
142 	if (child) {
143 		rcu_assign_sk_user_data(child, NULL);
144 
145 		/* v4-mapped sockets don't inherit parent ops. Don't restore. */
146 		if (inet_csk(child)->icsk_af_ops == inet_csk(sk)->icsk_af_ops)
147 			inet_csk(child)->icsk_af_ops = smc->ori_af_ops;
148 	}
149 	return child;
150 
151 drop:
152 	dst_release(dst);
153 	tcp_listendrop(sk);
154 	return NULL;
155 }
156 
157 static bool smc_hs_congested(const struct sock *sk)
158 {
159 	const struct smc_sock *smc;
160 
161 	smc = smc_clcsock_user_data(sk);
162 
163 	if (!smc)
164 		return true;
165 
166 	if (workqueue_congested(WORK_CPU_UNBOUND, smc_hs_wq))
167 		return true;
168 
169 	return false;
170 }
171 
172 static struct smc_hashinfo smc_v4_hashinfo = {
173 	.lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
174 };
175 
176 static struct smc_hashinfo smc_v6_hashinfo = {
177 	.lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
178 };
179 
180 int smc_hash_sk(struct sock *sk)
181 {
182 	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
183 	struct hlist_head *head;
184 
185 	head = &h->ht;
186 
187 	write_lock_bh(&h->lock);
188 	sk_add_node(sk, head);
189 	write_unlock_bh(&h->lock);
190 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
191 
192 	return 0;
193 }
194 EXPORT_SYMBOL_GPL(smc_hash_sk);
195 
196 void smc_unhash_sk(struct sock *sk)
197 {
198 	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
199 
200 	write_lock_bh(&h->lock);
201 	if (sk_del_node_init(sk))
202 		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
203 	write_unlock_bh(&h->lock);
204 }
205 EXPORT_SYMBOL_GPL(smc_unhash_sk);
206 
207 /* This will be called before user really release sock_lock. So do the
208  * work which we didn't do because of user hold the sock_lock in the
209  * BH context
210  */
211 static void smc_release_cb(struct sock *sk)
212 {
213 	struct smc_sock *smc = smc_sk(sk);
214 
215 	if (smc->conn.tx_in_release_sock) {
216 		smc_tx_pending(&smc->conn);
217 		smc->conn.tx_in_release_sock = false;
218 	}
219 }
220 
221 struct proto smc_proto = {
222 	.name		= "SMC",
223 	.owner		= THIS_MODULE,
224 	.keepalive	= smc_set_keepalive,
225 	.hash		= smc_hash_sk,
226 	.unhash		= smc_unhash_sk,
227 	.release_cb	= smc_release_cb,
228 	.obj_size	= sizeof(struct smc_sock),
229 	.h.smc_hash	= &smc_v4_hashinfo,
230 	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
231 };
232 EXPORT_SYMBOL_GPL(smc_proto);
233 
234 struct proto smc_proto6 = {
235 	.name		= "SMC6",
236 	.owner		= THIS_MODULE,
237 	.keepalive	= smc_set_keepalive,
238 	.hash		= smc_hash_sk,
239 	.unhash		= smc_unhash_sk,
240 	.release_cb	= smc_release_cb,
241 	.obj_size	= sizeof(struct smc_sock),
242 	.h.smc_hash	= &smc_v6_hashinfo,
243 	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
244 };
245 EXPORT_SYMBOL_GPL(smc_proto6);
246 
247 static void smc_fback_restore_callbacks(struct smc_sock *smc)
248 {
249 	struct sock *clcsk = smc->clcsock->sk;
250 
251 	write_lock_bh(&clcsk->sk_callback_lock);
252 	clcsk->sk_user_data = NULL;
253 
254 	smc_clcsock_restore_cb(&clcsk->sk_state_change, &smc->clcsk_state_change);
255 	smc_clcsock_restore_cb(&clcsk->sk_data_ready, &smc->clcsk_data_ready);
256 	smc_clcsock_restore_cb(&clcsk->sk_write_space, &smc->clcsk_write_space);
257 	smc_clcsock_restore_cb(&clcsk->sk_error_report, &smc->clcsk_error_report);
258 
259 	write_unlock_bh(&clcsk->sk_callback_lock);
260 }
261 
262 static void smc_restore_fallback_changes(struct smc_sock *smc)
263 {
264 	if (smc->clcsock->file) { /* non-accepted sockets have no file yet */
265 		smc->clcsock->file->private_data = smc->sk.sk_socket;
266 		smc->clcsock->file = NULL;
267 		smc_fback_restore_callbacks(smc);
268 	}
269 }
270 
271 static int __smc_release(struct smc_sock *smc)
272 {
273 	struct sock *sk = &smc->sk;
274 	int rc = 0;
275 
276 	if (!smc->use_fallback) {
277 		rc = smc_close_active(smc);
278 		smc_sock_set_flag(sk, SOCK_DEAD);
279 		sk->sk_shutdown |= SHUTDOWN_MASK;
280 	} else {
281 		if (sk->sk_state != SMC_CLOSED) {
282 			if (sk->sk_state != SMC_LISTEN &&
283 			    sk->sk_state != SMC_INIT)
284 				sock_put(sk); /* passive closing */
285 			if (sk->sk_state == SMC_LISTEN) {
286 				/* wake up clcsock accept */
287 				rc = kernel_sock_shutdown(smc->clcsock,
288 							  SHUT_RDWR);
289 			}
290 			sk->sk_state = SMC_CLOSED;
291 			sk->sk_state_change(sk);
292 		}
293 		smc_restore_fallback_changes(smc);
294 	}
295 
296 	sk->sk_prot->unhash(sk);
297 
298 	if (sk->sk_state == SMC_CLOSED) {
299 		if (smc->clcsock) {
300 			release_sock(sk);
301 			smc_clcsock_release(smc);
302 			lock_sock(sk);
303 		}
304 		if (!smc->use_fallback)
305 			smc_conn_free(&smc->conn);
306 	}
307 
308 	return rc;
309 }
310 
311 static int smc_release(struct socket *sock)
312 {
313 	struct sock *sk = sock->sk;
314 	struct smc_sock *smc;
315 	int old_state, rc = 0;
316 
317 	if (!sk)
318 		goto out;
319 
320 	sock_hold(sk); /* sock_put below */
321 	smc = smc_sk(sk);
322 
323 	old_state = sk->sk_state;
324 
325 	/* cleanup for a dangling non-blocking connect */
326 	if (smc->connect_nonblock && old_state == SMC_INIT)
327 		tcp_abort(smc->clcsock->sk, ECONNABORTED);
328 
329 	if (cancel_work_sync(&smc->connect_work))
330 		sock_put(&smc->sk); /* sock_hold in smc_connect for passive closing */
331 
332 	if (sk->sk_state == SMC_LISTEN)
333 		/* smc_close_non_accepted() is called and acquires
334 		 * sock lock for child sockets again
335 		 */
336 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
337 	else
338 		lock_sock(sk);
339 
340 	if (old_state == SMC_INIT && sk->sk_state == SMC_ACTIVE &&
341 	    !smc->use_fallback)
342 		smc_close_active_abort(smc);
343 
344 	rc = __smc_release(smc);
345 
346 	/* detach socket */
347 	sock_orphan(sk);
348 	sock->sk = NULL;
349 	release_sock(sk);
350 
351 	sock_put(sk); /* sock_hold above */
352 	sock_put(sk); /* final sock_put */
353 out:
354 	return rc;
355 }
356 
357 static void smc_destruct(struct sock *sk)
358 {
359 	if (sk->sk_state != SMC_CLOSED)
360 		return;
361 	if (!sock_flag(sk, SOCK_DEAD))
362 		return;
363 }
364 
365 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
366 				   int protocol)
367 {
368 	struct smc_sock *smc;
369 	struct proto *prot;
370 	struct sock *sk;
371 
372 	prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
373 	sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
374 	if (!sk)
375 		return NULL;
376 
377 	sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
378 	sk->sk_state = SMC_INIT;
379 	sk->sk_destruct = smc_destruct;
380 	sk->sk_protocol = protocol;
381 	WRITE_ONCE(sk->sk_sndbuf, 2 * READ_ONCE(net->smc.sysctl_wmem));
382 	WRITE_ONCE(sk->sk_rcvbuf, 2 * READ_ONCE(net->smc.sysctl_rmem));
383 	smc = smc_sk(sk);
384 	INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
385 	INIT_WORK(&smc->connect_work, smc_connect_work);
386 	INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
387 	INIT_LIST_HEAD(&smc->accept_q);
388 	spin_lock_init(&smc->accept_q_lock);
389 	spin_lock_init(&smc->conn.send_lock);
390 	sk->sk_prot->hash(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 	smc->clcsock->sk->sk_reuseport = sk->sk_reuseport;
431 	rc = kernel_bind(smc->clcsock, uaddr, addr_len);
432 
433 out_rel:
434 	release_sock(sk);
435 out:
436 	return rc;
437 }
438 
439 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
440  * clc socket (since smc is not called for these options from net/core)
441  */
442 
443 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
444 			     (1UL << SOCK_KEEPOPEN) | \
445 			     (1UL << SOCK_LINGER) | \
446 			     (1UL << SOCK_BROADCAST) | \
447 			     (1UL << SOCK_TIMESTAMP) | \
448 			     (1UL << SOCK_DBG) | \
449 			     (1UL << SOCK_RCVTSTAMP) | \
450 			     (1UL << SOCK_RCVTSTAMPNS) | \
451 			     (1UL << SOCK_LOCALROUTE) | \
452 			     (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
453 			     (1UL << SOCK_RXQ_OVFL) | \
454 			     (1UL << SOCK_WIFI_STATUS) | \
455 			     (1UL << SOCK_NOFCS) | \
456 			     (1UL << SOCK_FILTER_LOCKED) | \
457 			     (1UL << SOCK_TSTAMP_NEW))
458 
459 /* if set, use value set by setsockopt() - else use IPv4 or SMC sysctl value */
460 static void smc_adjust_sock_bufsizes(struct sock *nsk, struct sock *osk,
461 				     unsigned long mask)
462 {
463 	struct net *nnet = sock_net(nsk);
464 
465 	nsk->sk_userlocks = osk->sk_userlocks;
466 	if (osk->sk_userlocks & SOCK_SNDBUF_LOCK) {
467 		nsk->sk_sndbuf = osk->sk_sndbuf;
468 	} else {
469 		if (mask == SK_FLAGS_SMC_TO_CLC)
470 			WRITE_ONCE(nsk->sk_sndbuf,
471 				   READ_ONCE(nnet->ipv4.sysctl_tcp_wmem[1]));
472 		else
473 			WRITE_ONCE(nsk->sk_sndbuf,
474 				   2 * READ_ONCE(nnet->smc.sysctl_wmem));
475 	}
476 	if (osk->sk_userlocks & SOCK_RCVBUF_LOCK) {
477 		nsk->sk_rcvbuf = osk->sk_rcvbuf;
478 	} else {
479 		if (mask == SK_FLAGS_SMC_TO_CLC)
480 			WRITE_ONCE(nsk->sk_rcvbuf,
481 				   READ_ONCE(nnet->ipv4.sysctl_tcp_rmem[1]));
482 		else
483 			WRITE_ONCE(nsk->sk_rcvbuf,
484 				   2 * READ_ONCE(nnet->smc.sysctl_rmem));
485 	}
486 }
487 
488 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
489 				   unsigned long mask)
490 {
491 	/* options we don't get control via setsockopt for */
492 	nsk->sk_type = osk->sk_type;
493 	nsk->sk_sndtimeo = osk->sk_sndtimeo;
494 	nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
495 	nsk->sk_mark = READ_ONCE(osk->sk_mark);
496 	nsk->sk_priority = READ_ONCE(osk->sk_priority);
497 	nsk->sk_rcvlowat = osk->sk_rcvlowat;
498 	nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
499 	nsk->sk_err = osk->sk_err;
500 
501 	nsk->sk_flags &= ~mask;
502 	nsk->sk_flags |= osk->sk_flags & mask;
503 
504 	smc_adjust_sock_bufsizes(nsk, osk, mask);
505 }
506 
507 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
508 {
509 	smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
510 }
511 
512 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
513 			     (1UL << SOCK_KEEPOPEN) | \
514 			     (1UL << SOCK_LINGER) | \
515 			     (1UL << SOCK_DBG))
516 /* copy only settings and flags relevant for smc from clc to smc socket */
517 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
518 {
519 	smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
520 }
521 
522 /* register the new vzalloced sndbuf on all links */
523 static int smcr_lgr_reg_sndbufs(struct smc_link *link,
524 				struct smc_buf_desc *snd_desc)
525 {
526 	struct smc_link_group *lgr = link->lgr;
527 	int i, rc = 0;
528 
529 	if (!snd_desc->is_vm)
530 		return -EINVAL;
531 
532 	/* protect against parallel smcr_link_reg_buf() */
533 	down_write(&lgr->llc_conf_mutex);
534 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
535 		if (!smc_link_active(&lgr->lnk[i]))
536 			continue;
537 		rc = smcr_link_reg_buf(&lgr->lnk[i], snd_desc);
538 		if (rc)
539 			break;
540 	}
541 	up_write(&lgr->llc_conf_mutex);
542 	return rc;
543 }
544 
545 /* register the new rmb on all links */
546 static int smcr_lgr_reg_rmbs(struct smc_link *link,
547 			     struct smc_buf_desc *rmb_desc)
548 {
549 	struct smc_link_group *lgr = link->lgr;
550 	bool do_slow = false;
551 	int i, rc = 0;
552 
553 	rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
554 	if (rc)
555 		return rc;
556 
557 	down_read(&lgr->llc_conf_mutex);
558 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
559 		if (!smc_link_active(&lgr->lnk[i]))
560 			continue;
561 		if (!rmb_desc->is_reg_mr[link->link_idx]) {
562 			up_read(&lgr->llc_conf_mutex);
563 			goto slow_path;
564 		}
565 	}
566 	/* mr register already */
567 	goto fast_path;
568 slow_path:
569 	do_slow = true;
570 	/* protect against parallel smc_llc_cli_rkey_exchange() and
571 	 * parallel smcr_link_reg_buf()
572 	 */
573 	down_write(&lgr->llc_conf_mutex);
574 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
575 		if (!smc_link_active(&lgr->lnk[i]))
576 			continue;
577 		rc = smcr_link_reg_buf(&lgr->lnk[i], rmb_desc);
578 		if (rc)
579 			goto out;
580 	}
581 fast_path:
582 	/* exchange confirm_rkey msg with peer */
583 	rc = smc_llc_do_confirm_rkey(link, rmb_desc);
584 	if (rc) {
585 		rc = -EFAULT;
586 		goto out;
587 	}
588 	rmb_desc->is_conf_rkey = true;
589 out:
590 	do_slow ? up_write(&lgr->llc_conf_mutex) : up_read(&lgr->llc_conf_mutex);
591 	smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
592 	return rc;
593 }
594 
595 static int smcr_clnt_conf_first_link(struct smc_sock *smc)
596 {
597 	struct smc_link *link = smc->conn.lnk;
598 	struct smc_llc_qentry *qentry;
599 	int rc;
600 
601 	/* Receive CONFIRM LINK request from server over RoCE fabric.
602 	 * Increasing the client's timeout by twice as much as the server's
603 	 * timeout by default can temporarily avoid decline messages of
604 	 * both sides crossing or colliding
605 	 */
606 	qentry = smc_llc_wait(link->lgr, NULL, 2 * SMC_LLC_WAIT_TIME,
607 			      SMC_LLC_CONFIRM_LINK);
608 	if (!qentry) {
609 		struct smc_clc_msg_decline dclc;
610 
611 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
612 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
613 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
614 	}
615 	smc_llc_save_peer_uid(qentry);
616 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
617 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
618 	if (rc)
619 		return SMC_CLC_DECL_RMBE_EC;
620 
621 	rc = smc_ib_modify_qp_rts(link);
622 	if (rc)
623 		return SMC_CLC_DECL_ERR_RDYLNK;
624 
625 	smc_wr_remember_qp_attr(link);
626 
627 	/* reg the sndbuf if it was vzalloced */
628 	if (smc->conn.sndbuf_desc->is_vm) {
629 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
630 			return SMC_CLC_DECL_ERR_REGBUF;
631 	}
632 
633 	/* reg the rmb */
634 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
635 		return SMC_CLC_DECL_ERR_REGBUF;
636 
637 	/* confirm_rkey is implicit on 1st contact */
638 	smc->conn.rmb_desc->is_conf_rkey = true;
639 
640 	/* send CONFIRM LINK response over RoCE fabric */
641 	rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
642 	if (rc < 0)
643 		return SMC_CLC_DECL_TIMEOUT_CL;
644 
645 	smc_llc_link_active(link);
646 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
647 
648 	if (link->lgr->max_links > 1) {
649 		/* optional 2nd link, receive ADD LINK request from server */
650 		qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
651 				      SMC_LLC_ADD_LINK);
652 		if (!qentry) {
653 			struct smc_clc_msg_decline dclc;
654 
655 			rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
656 					      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
657 			if (rc == -EAGAIN)
658 				rc = 0; /* no DECLINE received, go with one link */
659 			return rc;
660 		}
661 		smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
662 		smc_llc_cli_add_link(link, qentry);
663 	}
664 	return 0;
665 }
666 
667 static bool smc_isascii(char *hostname)
668 {
669 	int i;
670 
671 	for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
672 		if (!isascii(hostname[i]))
673 			return false;
674 	return true;
675 }
676 
677 static void smc_conn_save_peer_info_fce(struct smc_sock *smc,
678 					struct smc_clc_msg_accept_confirm *clc)
679 {
680 	struct smc_clc_first_contact_ext *fce;
681 	int clc_v2_len;
682 
683 	if (clc->hdr.version == SMC_V1 ||
684 	    !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
685 		return;
686 
687 	if (smc->conn.lgr->is_smcd) {
688 		memcpy(smc->conn.lgr->negotiated_eid, clc->d1.eid,
689 		       SMC_MAX_EID_LEN);
690 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm, d1);
691 	} else {
692 		memcpy(smc->conn.lgr->negotiated_eid, clc->r1.eid,
693 		       SMC_MAX_EID_LEN);
694 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm, r1);
695 	}
696 	fce = (struct smc_clc_first_contact_ext *)(((u8 *)clc) + clc_v2_len);
697 	smc->conn.lgr->peer_os = fce->os_type;
698 	smc->conn.lgr->peer_smc_release = fce->release;
699 	if (smc_isascii(fce->hostname))
700 		memcpy(smc->conn.lgr->peer_hostname, fce->hostname,
701 		       SMC_MAX_HOSTNAME_LEN);
702 }
703 
704 static void smcr_conn_save_peer_info(struct smc_sock *smc,
705 				     struct smc_clc_msg_accept_confirm *clc)
706 {
707 	int bufsize = smc_uncompress_bufsize(clc->r0.rmbe_size);
708 
709 	smc->conn.peer_rmbe_idx = clc->r0.rmbe_idx;
710 	smc->conn.local_tx_ctrl.token = ntohl(clc->r0.rmbe_alert_token);
711 	smc->conn.peer_rmbe_size = bufsize;
712 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
713 	smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
714 }
715 
716 static void smcd_conn_save_peer_info(struct smc_sock *smc,
717 				     struct smc_clc_msg_accept_confirm *clc)
718 {
719 	int bufsize = smc_uncompress_bufsize(clc->d0.dmbe_size);
720 
721 	smc->conn.peer_rmbe_idx = clc->d0.dmbe_idx;
722 	smc->conn.peer_token = ntohll(clc->d0.token);
723 	/* msg header takes up space in the buffer */
724 	smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
725 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
726 	smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
727 }
728 
729 static void smc_conn_save_peer_info(struct smc_sock *smc,
730 				    struct smc_clc_msg_accept_confirm *clc)
731 {
732 	if (smc->conn.lgr->is_smcd)
733 		smcd_conn_save_peer_info(smc, clc);
734 	else
735 		smcr_conn_save_peer_info(smc, clc);
736 	smc_conn_save_peer_info_fce(smc, clc);
737 }
738 
739 static void smc_link_save_peer_info(struct smc_link *link,
740 				    struct smc_clc_msg_accept_confirm *clc,
741 				    struct smc_init_info *ini)
742 {
743 	link->peer_qpn = ntoh24(clc->r0.qpn);
744 	memcpy(link->peer_gid, ini->peer_gid, SMC_GID_SIZE);
745 	memcpy(link->peer_mac, ini->peer_mac, sizeof(link->peer_mac));
746 	link->peer_psn = ntoh24(clc->r0.psn);
747 	link->peer_mtu = clc->r0.qp_mtu;
748 }
749 
750 static void smc_stat_inc_fback_rsn_cnt(struct smc_sock *smc,
751 				       struct smc_stats_fback *fback_arr)
752 {
753 	int cnt;
754 
755 	for (cnt = 0; cnt < SMC_MAX_FBACK_RSN_CNT; cnt++) {
756 		if (fback_arr[cnt].fback_code == smc->fallback_rsn) {
757 			fback_arr[cnt].count++;
758 			break;
759 		}
760 		if (!fback_arr[cnt].fback_code) {
761 			fback_arr[cnt].fback_code = smc->fallback_rsn;
762 			fback_arr[cnt].count++;
763 			break;
764 		}
765 	}
766 }
767 
768 static void smc_stat_fallback(struct smc_sock *smc)
769 {
770 	struct net *net = sock_net(&smc->sk);
771 
772 	mutex_lock(&net->smc.mutex_fback_rsn);
773 	if (smc->listen_smc) {
774 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->srv);
775 		net->smc.fback_rsn->srv_fback_cnt++;
776 	} else {
777 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->clnt);
778 		net->smc.fback_rsn->clnt_fback_cnt++;
779 	}
780 	mutex_unlock(&net->smc.mutex_fback_rsn);
781 }
782 
783 /* must be called under rcu read lock */
784 static void smc_fback_wakeup_waitqueue(struct smc_sock *smc, void *key)
785 {
786 	struct socket_wq *wq;
787 	__poll_t flags;
788 
789 	wq = rcu_dereference(smc->sk.sk_wq);
790 	if (!skwq_has_sleeper(wq))
791 		return;
792 
793 	/* wake up smc sk->sk_wq */
794 	if (!key) {
795 		/* sk_state_change */
796 		wake_up_interruptible_all(&wq->wait);
797 	} else {
798 		flags = key_to_poll(key);
799 		if (flags & (EPOLLIN | EPOLLOUT))
800 			/* sk_data_ready or sk_write_space */
801 			wake_up_interruptible_sync_poll(&wq->wait, flags);
802 		else if (flags & EPOLLERR)
803 			/* sk_error_report */
804 			wake_up_interruptible_poll(&wq->wait, flags);
805 	}
806 }
807 
808 static int smc_fback_mark_woken(wait_queue_entry_t *wait,
809 				unsigned int mode, int sync, void *key)
810 {
811 	struct smc_mark_woken *mark =
812 		container_of(wait, struct smc_mark_woken, wait_entry);
813 
814 	mark->woken = true;
815 	mark->key = key;
816 	return 0;
817 }
818 
819 static void smc_fback_forward_wakeup(struct smc_sock *smc, struct sock *clcsk,
820 				     void (*clcsock_callback)(struct sock *sk))
821 {
822 	struct smc_mark_woken mark = { .woken = false };
823 	struct socket_wq *wq;
824 
825 	init_waitqueue_func_entry(&mark.wait_entry,
826 				  smc_fback_mark_woken);
827 	rcu_read_lock();
828 	wq = rcu_dereference(clcsk->sk_wq);
829 	if (!wq)
830 		goto out;
831 	add_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
832 	clcsock_callback(clcsk);
833 	remove_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
834 
835 	if (mark.woken)
836 		smc_fback_wakeup_waitqueue(smc, mark.key);
837 out:
838 	rcu_read_unlock();
839 }
840 
841 static void smc_fback_state_change(struct sock *clcsk)
842 {
843 	struct smc_sock *smc;
844 
845 	read_lock_bh(&clcsk->sk_callback_lock);
846 	smc = smc_clcsock_user_data(clcsk);
847 	if (smc)
848 		smc_fback_forward_wakeup(smc, clcsk,
849 					 smc->clcsk_state_change);
850 	read_unlock_bh(&clcsk->sk_callback_lock);
851 }
852 
853 static void smc_fback_data_ready(struct sock *clcsk)
854 {
855 	struct smc_sock *smc;
856 
857 	read_lock_bh(&clcsk->sk_callback_lock);
858 	smc = smc_clcsock_user_data(clcsk);
859 	if (smc)
860 		smc_fback_forward_wakeup(smc, clcsk,
861 					 smc->clcsk_data_ready);
862 	read_unlock_bh(&clcsk->sk_callback_lock);
863 }
864 
865 static void smc_fback_write_space(struct sock *clcsk)
866 {
867 	struct smc_sock *smc;
868 
869 	read_lock_bh(&clcsk->sk_callback_lock);
870 	smc = smc_clcsock_user_data(clcsk);
871 	if (smc)
872 		smc_fback_forward_wakeup(smc, clcsk,
873 					 smc->clcsk_write_space);
874 	read_unlock_bh(&clcsk->sk_callback_lock);
875 }
876 
877 static void smc_fback_error_report(struct sock *clcsk)
878 {
879 	struct smc_sock *smc;
880 
881 	read_lock_bh(&clcsk->sk_callback_lock);
882 	smc = smc_clcsock_user_data(clcsk);
883 	if (smc)
884 		smc_fback_forward_wakeup(smc, clcsk,
885 					 smc->clcsk_error_report);
886 	read_unlock_bh(&clcsk->sk_callback_lock);
887 }
888 
889 static void smc_fback_replace_callbacks(struct smc_sock *smc)
890 {
891 	struct sock *clcsk = smc->clcsock->sk;
892 
893 	write_lock_bh(&clcsk->sk_callback_lock);
894 	clcsk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
895 
896 	smc_clcsock_replace_cb(&clcsk->sk_state_change, smc_fback_state_change,
897 			       &smc->clcsk_state_change);
898 	smc_clcsock_replace_cb(&clcsk->sk_data_ready, smc_fback_data_ready,
899 			       &smc->clcsk_data_ready);
900 	smc_clcsock_replace_cb(&clcsk->sk_write_space, smc_fback_write_space,
901 			       &smc->clcsk_write_space);
902 	smc_clcsock_replace_cb(&clcsk->sk_error_report, smc_fback_error_report,
903 			       &smc->clcsk_error_report);
904 
905 	write_unlock_bh(&clcsk->sk_callback_lock);
906 }
907 
908 static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code)
909 {
910 	int rc = 0;
911 
912 	mutex_lock(&smc->clcsock_release_lock);
913 	if (!smc->clcsock) {
914 		rc = -EBADF;
915 		goto out;
916 	}
917 
918 	smc->use_fallback = true;
919 	smc->fallback_rsn = reason_code;
920 	smc_stat_fallback(smc);
921 	trace_smc_switch_to_fallback(smc, reason_code);
922 	if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
923 		smc->clcsock->file = smc->sk.sk_socket->file;
924 		smc->clcsock->file->private_data = smc->clcsock;
925 		smc->clcsock->wq.fasync_list =
926 			smc->sk.sk_socket->wq.fasync_list;
927 
928 		/* There might be some wait entries remaining
929 		 * in smc sk->sk_wq and they should be woken up
930 		 * as clcsock's wait queue is woken up.
931 		 */
932 		smc_fback_replace_callbacks(smc);
933 	}
934 out:
935 	mutex_unlock(&smc->clcsock_release_lock);
936 	return rc;
937 }
938 
939 /* fall back during connect */
940 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
941 {
942 	struct net *net = sock_net(&smc->sk);
943 	int rc = 0;
944 
945 	rc = smc_switch_to_fallback(smc, reason_code);
946 	if (rc) { /* fallback fails */
947 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
948 		if (smc->sk.sk_state == SMC_INIT)
949 			sock_put(&smc->sk); /* passive closing */
950 		return rc;
951 	}
952 	smc_copy_sock_settings_to_clc(smc);
953 	smc->connect_nonblock = 0;
954 	if (smc->sk.sk_state == SMC_INIT)
955 		smc->sk.sk_state = SMC_ACTIVE;
956 	return 0;
957 }
958 
959 /* decline and fall back during connect */
960 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
961 					u8 version)
962 {
963 	struct net *net = sock_net(&smc->sk);
964 	int rc;
965 
966 	if (reason_code < 0) { /* error, fallback is not possible */
967 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
968 		if (smc->sk.sk_state == SMC_INIT)
969 			sock_put(&smc->sk); /* passive closing */
970 		return reason_code;
971 	}
972 	if (reason_code != SMC_CLC_DECL_PEERDECL) {
973 		rc = smc_clc_send_decline(smc, reason_code, version);
974 		if (rc < 0) {
975 			this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
976 			if (smc->sk.sk_state == SMC_INIT)
977 				sock_put(&smc->sk); /* passive closing */
978 			return rc;
979 		}
980 	}
981 	return smc_connect_fallback(smc, reason_code);
982 }
983 
984 static void smc_conn_abort(struct smc_sock *smc, int local_first)
985 {
986 	struct smc_connection *conn = &smc->conn;
987 	struct smc_link_group *lgr = conn->lgr;
988 	bool lgr_valid = false;
989 
990 	if (smc_conn_lgr_valid(conn))
991 		lgr_valid = true;
992 
993 	smc_conn_free(conn);
994 	if (local_first && lgr_valid)
995 		smc_lgr_cleanup_early(lgr);
996 }
997 
998 /* check if there is a rdma device available for this connection. */
999 /* called for connect and listen */
1000 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
1001 {
1002 	/* PNET table look up: search active ib_device and port
1003 	 * within same PNETID that also contains the ethernet device
1004 	 * used for the internal TCP socket
1005 	 */
1006 	smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
1007 	if (!ini->check_smcrv2 && !ini->ib_dev)
1008 		return SMC_CLC_DECL_NOSMCRDEV;
1009 	if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
1010 		return SMC_CLC_DECL_NOSMCRDEV;
1011 	return 0;
1012 }
1013 
1014 /* check if there is an ISM device available for this connection. */
1015 /* called for connect and listen */
1016 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
1017 {
1018 	/* Find ISM device with same PNETID as connecting interface  */
1019 	smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
1020 	if (!ini->ism_dev[0])
1021 		return SMC_CLC_DECL_NOSMCDDEV;
1022 	else
1023 		ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
1024 	return 0;
1025 }
1026 
1027 /* is chid unique for the ism devices that are already determined? */
1028 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
1029 					   int cnt)
1030 {
1031 	int i = (!ini->ism_dev[0]) ? 1 : 0;
1032 
1033 	for (; i < cnt; i++)
1034 		if (ini->ism_chid[i] == chid)
1035 			return false;
1036 	return true;
1037 }
1038 
1039 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
1040  * PNETID matching net_device)
1041  */
1042 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
1043 				       struct smc_init_info *ini)
1044 {
1045 	int rc = SMC_CLC_DECL_NOSMCDDEV;
1046 	struct smcd_dev *smcd;
1047 	int i = 1, entry = 1;
1048 	bool is_virtual;
1049 	u16 chid;
1050 
1051 	if (smcd_indicated(ini->smc_type_v1))
1052 		rc = 0;		/* already initialized for V1 */
1053 	mutex_lock(&smcd_dev_list.mutex);
1054 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1055 		if (smcd->going_away || smcd == ini->ism_dev[0])
1056 			continue;
1057 		chid = smc_ism_get_chid(smcd);
1058 		if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
1059 			continue;
1060 		is_virtual = __smc_ism_is_virtual(chid);
1061 		if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
1062 		    smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
1063 			if (is_virtual && entry == SMCD_CLC_MAX_V2_GID_ENTRIES)
1064 				/* It's the last GID-CHID entry left in CLC
1065 				 * Proposal SMC-Dv2 extension, but a virtual
1066 				 * ISM device will take two entries. So give
1067 				 * up it and try the next potential ISM device.
1068 				 */
1069 				continue;
1070 			ini->ism_dev[i] = smcd;
1071 			ini->ism_chid[i] = chid;
1072 			ini->is_smcd = true;
1073 			rc = 0;
1074 			i++;
1075 			entry = is_virtual ? entry + 2 : entry + 1;
1076 			if (entry > SMCD_CLC_MAX_V2_GID_ENTRIES)
1077 				break;
1078 		}
1079 	}
1080 	mutex_unlock(&smcd_dev_list.mutex);
1081 	ini->ism_offered_cnt = i - 1;
1082 	if (!ini->ism_dev[0] && !ini->ism_dev[1])
1083 		ini->smcd_version = 0;
1084 
1085 	return rc;
1086 }
1087 
1088 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
1089 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
1090 				      struct smc_init_info *ini)
1091 {
1092 	if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
1093 		return SMC_CLC_DECL_ISMVLANERR;
1094 	return 0;
1095 }
1096 
1097 static int smc_find_proposal_devices(struct smc_sock *smc,
1098 				     struct smc_init_info *ini)
1099 {
1100 	int rc = 0;
1101 
1102 	/* check if there is an ism device available */
1103 	if (!(ini->smcd_version & SMC_V1) ||
1104 	    smc_find_ism_device(smc, ini) ||
1105 	    smc_connect_ism_vlan_setup(smc, ini))
1106 		ini->smcd_version &= ~SMC_V1;
1107 	/* else ISM V1 is supported for this connection */
1108 
1109 	/* check if there is an rdma device available */
1110 	if (!(ini->smcr_version & SMC_V1) ||
1111 	    smc_find_rdma_device(smc, ini))
1112 		ini->smcr_version &= ~SMC_V1;
1113 	/* else RDMA is supported for this connection */
1114 
1115 	ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
1116 					      ini->smcr_version & SMC_V1);
1117 
1118 	/* check if there is an ism v2 device available */
1119 	if (!(ini->smcd_version & SMC_V2) ||
1120 	    !smc_ism_is_v2_capable() ||
1121 	    smc_find_ism_v2_device_clnt(smc, ini))
1122 		ini->smcd_version &= ~SMC_V2;
1123 
1124 	/* check if there is an rdma v2 device available */
1125 	ini->check_smcrv2 = true;
1126 	ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
1127 	if (!(ini->smcr_version & SMC_V2) ||
1128 	    smc->clcsock->sk->sk_family != AF_INET ||
1129 	    !smc_clc_ueid_count() ||
1130 	    smc_find_rdma_device(smc, ini))
1131 		ini->smcr_version &= ~SMC_V2;
1132 	ini->check_smcrv2 = false;
1133 
1134 	ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
1135 					      ini->smcr_version & SMC_V2);
1136 
1137 	/* if neither ISM nor RDMA are supported, fallback */
1138 	if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
1139 		rc = SMC_CLC_DECL_NOSMCDEV;
1140 
1141 	return rc;
1142 }
1143 
1144 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
1145  * used, the VLAN ID will be registered again during the connection setup.
1146  */
1147 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
1148 					struct smc_init_info *ini)
1149 {
1150 	if (!smcd_indicated(ini->smc_type_v1))
1151 		return 0;
1152 	if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
1153 		return SMC_CLC_DECL_CNFERR;
1154 	return 0;
1155 }
1156 
1157 #define SMC_CLC_MAX_ACCEPT_LEN \
1158 	(sizeof(struct smc_clc_msg_accept_confirm) + \
1159 	 sizeof(struct smc_clc_first_contact_ext_v2x) + \
1160 	 sizeof(struct smc_clc_msg_trail))
1161 
1162 /* CLC handshake during connect */
1163 static int smc_connect_clc(struct smc_sock *smc,
1164 			   struct smc_clc_msg_accept_confirm *aclc,
1165 			   struct smc_init_info *ini)
1166 {
1167 	int rc = 0;
1168 
1169 	/* do inband token exchange */
1170 	rc = smc_clc_send_proposal(smc, ini);
1171 	if (rc)
1172 		return rc;
1173 	/* receive SMC Accept CLC message */
1174 	return smc_clc_wait_msg(smc, aclc, SMC_CLC_MAX_ACCEPT_LEN,
1175 				SMC_CLC_ACCEPT, CLC_WAIT_TIME);
1176 }
1177 
1178 void smc_fill_gid_list(struct smc_link_group *lgr,
1179 		       struct smc_gidlist *gidlist,
1180 		       struct smc_ib_device *known_dev, u8 *known_gid)
1181 {
1182 	struct smc_init_info *alt_ini = NULL;
1183 
1184 	memset(gidlist, 0, sizeof(*gidlist));
1185 	memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
1186 
1187 	alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
1188 	if (!alt_ini)
1189 		goto out;
1190 
1191 	alt_ini->vlan_id = lgr->vlan_id;
1192 	alt_ini->check_smcrv2 = true;
1193 	alt_ini->smcrv2.saddr = lgr->saddr;
1194 	smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
1195 
1196 	if (!alt_ini->smcrv2.ib_dev_v2)
1197 		goto out;
1198 
1199 	memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
1200 	       SMC_GID_SIZE);
1201 
1202 out:
1203 	kfree(alt_ini);
1204 }
1205 
1206 static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
1207 				       struct smc_clc_msg_accept_confirm *aclc,
1208 				       struct smc_init_info *ini)
1209 {
1210 	struct smc_clc_first_contact_ext *fce =
1211 		smc_get_clc_first_contact_ext(aclc, false);
1212 	struct net *net = sock_net(&smc->sk);
1213 	int rc;
1214 
1215 	if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1216 		return 0;
1217 
1218 	if (fce->v2_direct) {
1219 		memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1220 		ini->smcrv2.uses_gateway = false;
1221 	} else {
1222 		if (smc_ib_find_route(net, smc->clcsock->sk->sk_rcv_saddr,
1223 				      smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1224 				      ini->smcrv2.nexthop_mac,
1225 				      &ini->smcrv2.uses_gateway))
1226 			return SMC_CLC_DECL_NOROUTE;
1227 		if (!ini->smcrv2.uses_gateway) {
1228 			/* mismatch: peer claims indirect, but its direct */
1229 			return SMC_CLC_DECL_NOINDIRECT;
1230 		}
1231 	}
1232 
1233 	ini->release_nr = fce->release;
1234 	rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1235 	if (rc)
1236 		return rc;
1237 
1238 	return 0;
1239 }
1240 
1241 /* setup for RDMA connection of client */
1242 static int smc_connect_rdma(struct smc_sock *smc,
1243 			    struct smc_clc_msg_accept_confirm *aclc,
1244 			    struct smc_init_info *ini)
1245 {
1246 	int i, reason_code = 0;
1247 	struct smc_link *link;
1248 	u8 *eid = NULL;
1249 
1250 	ini->is_smcd = false;
1251 	ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1252 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1253 	memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1254 	memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1255 	memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1256 	ini->max_conns = SMC_CONN_PER_LGR_MAX;
1257 	ini->max_links = SMC_LINKS_ADD_LNK_MAX;
1258 
1259 	reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1260 	if (reason_code)
1261 		return reason_code;
1262 
1263 	mutex_lock(&smc_client_lgr_pending);
1264 	reason_code = smc_conn_create(smc, ini);
1265 	if (reason_code) {
1266 		mutex_unlock(&smc_client_lgr_pending);
1267 		return reason_code;
1268 	}
1269 
1270 	smc_conn_save_peer_info(smc, aclc);
1271 
1272 	if (ini->first_contact_local) {
1273 		link = smc->conn.lnk;
1274 	} else {
1275 		/* set link that was assigned by server */
1276 		link = NULL;
1277 		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1278 			struct smc_link *l = &smc->conn.lgr->lnk[i];
1279 
1280 			if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1281 			    !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1282 				    SMC_GID_SIZE) &&
1283 			    (aclc->hdr.version > SMC_V1 ||
1284 			     !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1285 				     sizeof(l->peer_mac)))) {
1286 				link = l;
1287 				break;
1288 			}
1289 		}
1290 		if (!link) {
1291 			reason_code = SMC_CLC_DECL_NOSRVLINK;
1292 			goto connect_abort;
1293 		}
1294 		smc_switch_link_and_count(&smc->conn, link);
1295 	}
1296 
1297 	/* create send buffer and rmb */
1298 	if (smc_buf_create(smc, false)) {
1299 		reason_code = SMC_CLC_DECL_MEM;
1300 		goto connect_abort;
1301 	}
1302 
1303 	if (ini->first_contact_local)
1304 		smc_link_save_peer_info(link, aclc, ini);
1305 
1306 	if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1307 		reason_code = SMC_CLC_DECL_ERR_RTOK;
1308 		goto connect_abort;
1309 	}
1310 
1311 	smc_close_init(smc);
1312 	smc_rx_init(smc);
1313 
1314 	if (ini->first_contact_local) {
1315 		if (smc_ib_ready_link(link)) {
1316 			reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1317 			goto connect_abort;
1318 		}
1319 	} else {
1320 		/* reg sendbufs if they were vzalloced */
1321 		if (smc->conn.sndbuf_desc->is_vm) {
1322 			if (smcr_lgr_reg_sndbufs(link, smc->conn.sndbuf_desc)) {
1323 				reason_code = SMC_CLC_DECL_ERR_REGBUF;
1324 				goto connect_abort;
1325 			}
1326 		}
1327 		if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1328 			reason_code = SMC_CLC_DECL_ERR_REGBUF;
1329 			goto connect_abort;
1330 		}
1331 	}
1332 
1333 	if (aclc->hdr.version > SMC_V1) {
1334 		eid = aclc->r1.eid;
1335 		if (ini->first_contact_local)
1336 			smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1337 					  link->smcibdev, link->gid);
1338 	}
1339 
1340 	reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1341 					   aclc->hdr.version, eid, ini);
1342 	if (reason_code)
1343 		goto connect_abort;
1344 
1345 	smc_tx_init(smc);
1346 
1347 	if (ini->first_contact_local) {
1348 		/* QP confirmation over RoCE fabric */
1349 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1350 		reason_code = smcr_clnt_conf_first_link(smc);
1351 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1352 		if (reason_code)
1353 			goto connect_abort;
1354 	}
1355 	mutex_unlock(&smc_client_lgr_pending);
1356 
1357 	smc_copy_sock_settings_to_clc(smc);
1358 	smc->connect_nonblock = 0;
1359 	if (smc->sk.sk_state == SMC_INIT)
1360 		smc->sk.sk_state = SMC_ACTIVE;
1361 
1362 	return 0;
1363 connect_abort:
1364 	smc_conn_abort(smc, ini->first_contact_local);
1365 	mutex_unlock(&smc_client_lgr_pending);
1366 	smc->connect_nonblock = 0;
1367 
1368 	return reason_code;
1369 }
1370 
1371 /* The server has chosen one of the proposed ISM devices for the communication.
1372  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1373  */
1374 static int
1375 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm *aclc,
1376 			       struct smc_init_info *ini)
1377 {
1378 	int i;
1379 
1380 	for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1381 		if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1382 			ini->ism_selected = i;
1383 			return 0;
1384 		}
1385 	}
1386 
1387 	return -EPROTO;
1388 }
1389 
1390 /* setup for ISM connection of client */
1391 static int smc_connect_ism(struct smc_sock *smc,
1392 			   struct smc_clc_msg_accept_confirm *aclc,
1393 			   struct smc_init_info *ini)
1394 {
1395 	u8 *eid = NULL;
1396 	int rc = 0;
1397 
1398 	ini->is_smcd = true;
1399 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1400 
1401 	if (aclc->hdr.version == SMC_V2) {
1402 		if (ini->first_contact_peer) {
1403 			struct smc_clc_first_contact_ext *fce =
1404 				smc_get_clc_first_contact_ext(aclc, true);
1405 
1406 			ini->release_nr = fce->release;
1407 			rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1408 			if (rc)
1409 				return rc;
1410 		}
1411 
1412 		rc = smc_v2_determine_accepted_chid(aclc, ini);
1413 		if (rc)
1414 			return rc;
1415 
1416 		if (__smc_ism_is_virtual(ini->ism_chid[ini->ism_selected]))
1417 			ini->ism_peer_gid[ini->ism_selected].gid_ext =
1418 						ntohll(aclc->d1.gid_ext);
1419 		/* for non-virtual ISM devices, peer gid_ext remains 0. */
1420 	}
1421 	ini->ism_peer_gid[ini->ism_selected].gid = ntohll(aclc->d0.gid);
1422 
1423 	/* there is only one lgr role for SMC-D; use server lock */
1424 	mutex_lock(&smc_server_lgr_pending);
1425 	rc = smc_conn_create(smc, ini);
1426 	if (rc) {
1427 		mutex_unlock(&smc_server_lgr_pending);
1428 		return rc;
1429 	}
1430 
1431 	/* Create send and receive buffers */
1432 	rc = smc_buf_create(smc, true);
1433 	if (rc) {
1434 		rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1435 		goto connect_abort;
1436 	}
1437 
1438 	smc_conn_save_peer_info(smc, aclc);
1439 	smc_close_init(smc);
1440 	smc_rx_init(smc);
1441 	smc_tx_init(smc);
1442 
1443 	if (aclc->hdr.version > SMC_V1)
1444 		eid = aclc->d1.eid;
1445 
1446 	rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1447 				  aclc->hdr.version, eid, ini);
1448 	if (rc)
1449 		goto connect_abort;
1450 	mutex_unlock(&smc_server_lgr_pending);
1451 
1452 	smc_copy_sock_settings_to_clc(smc);
1453 	smc->connect_nonblock = 0;
1454 	if (smc->sk.sk_state == SMC_INIT)
1455 		smc->sk.sk_state = SMC_ACTIVE;
1456 
1457 	return 0;
1458 connect_abort:
1459 	smc_conn_abort(smc, ini->first_contact_local);
1460 	mutex_unlock(&smc_server_lgr_pending);
1461 	smc->connect_nonblock = 0;
1462 
1463 	return rc;
1464 }
1465 
1466 /* check if received accept type and version matches a proposed one */
1467 static int smc_connect_check_aclc(struct smc_init_info *ini,
1468 				  struct smc_clc_msg_accept_confirm *aclc)
1469 {
1470 	if (aclc->hdr.typev1 != SMC_TYPE_R &&
1471 	    aclc->hdr.typev1 != SMC_TYPE_D)
1472 		return SMC_CLC_DECL_MODEUNSUPP;
1473 
1474 	if (aclc->hdr.version >= SMC_V2) {
1475 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1476 		     !smcr_indicated(ini->smc_type_v2)) ||
1477 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1478 		     !smcd_indicated(ini->smc_type_v2)))
1479 			return SMC_CLC_DECL_MODEUNSUPP;
1480 	} else {
1481 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1482 		     !smcr_indicated(ini->smc_type_v1)) ||
1483 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1484 		     !smcd_indicated(ini->smc_type_v1)))
1485 			return SMC_CLC_DECL_MODEUNSUPP;
1486 	}
1487 
1488 	return 0;
1489 }
1490 
1491 /* perform steps before actually connecting */
1492 static int __smc_connect(struct smc_sock *smc)
1493 {
1494 	u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1495 	struct smc_clc_msg_accept_confirm *aclc;
1496 	struct smc_init_info *ini = NULL;
1497 	u8 *buf = NULL;
1498 	int rc = 0;
1499 
1500 	if (smc->use_fallback)
1501 		return smc_connect_fallback(smc, smc->fallback_rsn);
1502 
1503 	/* if peer has not signalled SMC-capability, fall back */
1504 	if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1505 		return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1506 
1507 	/* IPSec connections opt out of SMC optimizations */
1508 	if (using_ipsec(smc))
1509 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1510 						    version);
1511 
1512 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1513 	if (!ini)
1514 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1515 						    version);
1516 
1517 	ini->smcd_version = SMC_V1 | SMC_V2;
1518 	ini->smcr_version = SMC_V1 | SMC_V2;
1519 	ini->smc_type_v1 = SMC_TYPE_B;
1520 	ini->smc_type_v2 = SMC_TYPE_B;
1521 
1522 	/* get vlan id from IP device */
1523 	if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1524 		ini->smcd_version &= ~SMC_V1;
1525 		ini->smcr_version = 0;
1526 		ini->smc_type_v1 = SMC_TYPE_N;
1527 		if (!ini->smcd_version) {
1528 			rc = SMC_CLC_DECL_GETVLANERR;
1529 			goto fallback;
1530 		}
1531 	}
1532 
1533 	rc = smc_find_proposal_devices(smc, ini);
1534 	if (rc)
1535 		goto fallback;
1536 
1537 	buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1538 	if (!buf) {
1539 		rc = SMC_CLC_DECL_MEM;
1540 		goto fallback;
1541 	}
1542 	aclc = (struct smc_clc_msg_accept_confirm *)buf;
1543 
1544 	/* perform CLC handshake */
1545 	rc = smc_connect_clc(smc, aclc, ini);
1546 	if (rc) {
1547 		/* -EAGAIN on timeout, see tcp_recvmsg() */
1548 		if (rc == -EAGAIN) {
1549 			rc = -ETIMEDOUT;
1550 			smc->sk.sk_err = ETIMEDOUT;
1551 		}
1552 		goto vlan_cleanup;
1553 	}
1554 
1555 	/* check if smc modes and versions of CLC proposal and accept match */
1556 	rc = smc_connect_check_aclc(ini, aclc);
1557 	version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1558 	if (rc)
1559 		goto vlan_cleanup;
1560 
1561 	/* depending on previous steps, connect using rdma or ism */
1562 	if (aclc->hdr.typev1 == SMC_TYPE_R) {
1563 		ini->smcr_version = version;
1564 		rc = smc_connect_rdma(smc, aclc, ini);
1565 	} else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1566 		ini->smcd_version = version;
1567 		rc = smc_connect_ism(smc, aclc, ini);
1568 	}
1569 	if (rc)
1570 		goto vlan_cleanup;
1571 
1572 	SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1573 	smc_connect_ism_vlan_cleanup(smc, ini);
1574 	kfree(buf);
1575 	kfree(ini);
1576 	return 0;
1577 
1578 vlan_cleanup:
1579 	smc_connect_ism_vlan_cleanup(smc, ini);
1580 	kfree(buf);
1581 fallback:
1582 	kfree(ini);
1583 	return smc_connect_decline_fallback(smc, rc, version);
1584 }
1585 
1586 static void smc_connect_work(struct work_struct *work)
1587 {
1588 	struct smc_sock *smc = container_of(work, struct smc_sock,
1589 					    connect_work);
1590 	long timeo = smc->sk.sk_sndtimeo;
1591 	int rc = 0;
1592 
1593 	if (!timeo)
1594 		timeo = MAX_SCHEDULE_TIMEOUT;
1595 	lock_sock(smc->clcsock->sk);
1596 	if (smc->clcsock->sk->sk_err) {
1597 		smc->sk.sk_err = smc->clcsock->sk->sk_err;
1598 	} else if ((1 << smc->clcsock->sk->sk_state) &
1599 					(TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1600 		rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1601 		if ((rc == -EPIPE) &&
1602 		    ((1 << smc->clcsock->sk->sk_state) &
1603 					(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1604 			rc = 0;
1605 	}
1606 	release_sock(smc->clcsock->sk);
1607 	lock_sock(&smc->sk);
1608 	if (rc != 0 || smc->sk.sk_err) {
1609 		smc->sk.sk_state = SMC_CLOSED;
1610 		if (rc == -EPIPE || rc == -EAGAIN)
1611 			smc->sk.sk_err = EPIPE;
1612 		else if (rc == -ECONNREFUSED)
1613 			smc->sk.sk_err = ECONNREFUSED;
1614 		else if (signal_pending(current))
1615 			smc->sk.sk_err = -sock_intr_errno(timeo);
1616 		sock_put(&smc->sk); /* passive closing */
1617 		goto out;
1618 	}
1619 
1620 	rc = __smc_connect(smc);
1621 	if (rc < 0)
1622 		smc->sk.sk_err = -rc;
1623 
1624 out:
1625 	if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1626 		if (smc->sk.sk_err) {
1627 			smc->sk.sk_state_change(&smc->sk);
1628 		} else { /* allow polling before and after fallback decision */
1629 			smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1630 			smc->sk.sk_write_space(&smc->sk);
1631 		}
1632 	}
1633 	release_sock(&smc->sk);
1634 }
1635 
1636 static int smc_connect(struct socket *sock, struct sockaddr *addr,
1637 		       int alen, int flags)
1638 {
1639 	struct sock *sk = sock->sk;
1640 	struct smc_sock *smc;
1641 	int rc = -EINVAL;
1642 
1643 	smc = smc_sk(sk);
1644 
1645 	/* separate smc parameter checking to be safe */
1646 	if (alen < sizeof(addr->sa_family))
1647 		goto out_err;
1648 	if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1649 		goto out_err;
1650 
1651 	lock_sock(sk);
1652 	switch (sock->state) {
1653 	default:
1654 		rc = -EINVAL;
1655 		goto out;
1656 	case SS_CONNECTED:
1657 		rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1658 		goto out;
1659 	case SS_CONNECTING:
1660 		if (sk->sk_state == SMC_ACTIVE)
1661 			goto connected;
1662 		break;
1663 	case SS_UNCONNECTED:
1664 		sock->state = SS_CONNECTING;
1665 		break;
1666 	}
1667 
1668 	switch (sk->sk_state) {
1669 	default:
1670 		goto out;
1671 	case SMC_CLOSED:
1672 		rc = sock_error(sk) ? : -ECONNABORTED;
1673 		sock->state = SS_UNCONNECTED;
1674 		goto out;
1675 	case SMC_ACTIVE:
1676 		rc = -EISCONN;
1677 		goto out;
1678 	case SMC_INIT:
1679 		break;
1680 	}
1681 
1682 	smc_copy_sock_settings_to_clc(smc);
1683 	tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1684 	if (smc->connect_nonblock) {
1685 		rc = -EALREADY;
1686 		goto out;
1687 	}
1688 	rc = kernel_connect(smc->clcsock, addr, alen, flags);
1689 	if (rc && rc != -EINPROGRESS)
1690 		goto out;
1691 
1692 	if (smc->use_fallback) {
1693 		sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1694 		goto out;
1695 	}
1696 	sock_hold(&smc->sk); /* sock put in passive closing */
1697 	if (flags & O_NONBLOCK) {
1698 		if (queue_work(smc_hs_wq, &smc->connect_work))
1699 			smc->connect_nonblock = 1;
1700 		rc = -EINPROGRESS;
1701 		goto out;
1702 	} else {
1703 		rc = __smc_connect(smc);
1704 		if (rc < 0)
1705 			goto out;
1706 	}
1707 
1708 connected:
1709 	rc = 0;
1710 	sock->state = SS_CONNECTED;
1711 out:
1712 	release_sock(sk);
1713 out_err:
1714 	return rc;
1715 }
1716 
1717 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1718 {
1719 	struct socket *new_clcsock = NULL;
1720 	struct sock *lsk = &lsmc->sk;
1721 	struct sock *new_sk;
1722 	int rc = -EINVAL;
1723 
1724 	release_sock(lsk);
1725 	new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1726 	if (!new_sk) {
1727 		rc = -ENOMEM;
1728 		lsk->sk_err = ENOMEM;
1729 		*new_smc = NULL;
1730 		lock_sock(lsk);
1731 		goto out;
1732 	}
1733 	*new_smc = smc_sk(new_sk);
1734 
1735 	mutex_lock(&lsmc->clcsock_release_lock);
1736 	if (lsmc->clcsock)
1737 		rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1738 	mutex_unlock(&lsmc->clcsock_release_lock);
1739 	lock_sock(lsk);
1740 	if  (rc < 0 && rc != -EAGAIN)
1741 		lsk->sk_err = -rc;
1742 	if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1743 		new_sk->sk_prot->unhash(new_sk);
1744 		if (new_clcsock)
1745 			sock_release(new_clcsock);
1746 		new_sk->sk_state = SMC_CLOSED;
1747 		smc_sock_set_flag(new_sk, SOCK_DEAD);
1748 		sock_put(new_sk); /* final */
1749 		*new_smc = NULL;
1750 		goto out;
1751 	}
1752 
1753 	/* new clcsock has inherited the smc listen-specific sk_data_ready
1754 	 * function; switch it back to the original sk_data_ready function
1755 	 */
1756 	new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1757 
1758 	/* if new clcsock has also inherited the fallback-specific callback
1759 	 * functions, switch them back to the original ones.
1760 	 */
1761 	if (lsmc->use_fallback) {
1762 		if (lsmc->clcsk_state_change)
1763 			new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1764 		if (lsmc->clcsk_write_space)
1765 			new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1766 		if (lsmc->clcsk_error_report)
1767 			new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1768 	}
1769 
1770 	(*new_smc)->clcsock = new_clcsock;
1771 out:
1772 	return rc;
1773 }
1774 
1775 /* add a just created sock to the accept queue of the listen sock as
1776  * candidate for a following socket accept call from user space
1777  */
1778 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1779 {
1780 	struct smc_sock *par = smc_sk(parent);
1781 
1782 	sock_hold(sk); /* sock_put in smc_accept_unlink () */
1783 	spin_lock(&par->accept_q_lock);
1784 	list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1785 	spin_unlock(&par->accept_q_lock);
1786 	sk_acceptq_added(parent);
1787 }
1788 
1789 /* remove a socket from the accept queue of its parental listening socket */
1790 static void smc_accept_unlink(struct sock *sk)
1791 {
1792 	struct smc_sock *par = smc_sk(sk)->listen_smc;
1793 
1794 	spin_lock(&par->accept_q_lock);
1795 	list_del_init(&smc_sk(sk)->accept_q);
1796 	spin_unlock(&par->accept_q_lock);
1797 	sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1798 	sock_put(sk); /* sock_hold in smc_accept_enqueue */
1799 }
1800 
1801 /* remove a sock from the accept queue to bind it to a new socket created
1802  * for a socket accept call from user space
1803  */
1804 struct sock *smc_accept_dequeue(struct sock *parent,
1805 				struct socket *new_sock)
1806 {
1807 	struct smc_sock *isk, *n;
1808 	struct sock *new_sk;
1809 
1810 	list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1811 		new_sk = (struct sock *)isk;
1812 
1813 		smc_accept_unlink(new_sk);
1814 		if (new_sk->sk_state == SMC_CLOSED) {
1815 			new_sk->sk_prot->unhash(new_sk);
1816 			if (isk->clcsock) {
1817 				sock_release(isk->clcsock);
1818 				isk->clcsock = NULL;
1819 			}
1820 			sock_put(new_sk); /* final */
1821 			continue;
1822 		}
1823 		if (new_sock) {
1824 			sock_graft(new_sk, new_sock);
1825 			new_sock->state = SS_CONNECTED;
1826 			if (isk->use_fallback) {
1827 				smc_sk(new_sk)->clcsock->file = new_sock->file;
1828 				isk->clcsock->file->private_data = isk->clcsock;
1829 			}
1830 		}
1831 		return new_sk;
1832 	}
1833 	return NULL;
1834 }
1835 
1836 /* clean up for a created but never accepted sock */
1837 void smc_close_non_accepted(struct sock *sk)
1838 {
1839 	struct smc_sock *smc = smc_sk(sk);
1840 
1841 	sock_hold(sk); /* sock_put below */
1842 	lock_sock(sk);
1843 	if (!sk->sk_lingertime)
1844 		/* wait for peer closing */
1845 		WRITE_ONCE(sk->sk_lingertime, SMC_MAX_STREAM_WAIT_TIMEOUT);
1846 	__smc_release(smc);
1847 	release_sock(sk);
1848 	sock_put(sk); /* sock_hold above */
1849 	sock_put(sk); /* final sock_put */
1850 }
1851 
1852 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1853 {
1854 	struct smc_link *link = smc->conn.lnk;
1855 	struct smc_llc_qentry *qentry;
1856 	int rc;
1857 
1858 	/* reg the sndbuf if it was vzalloced*/
1859 	if (smc->conn.sndbuf_desc->is_vm) {
1860 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
1861 			return SMC_CLC_DECL_ERR_REGBUF;
1862 	}
1863 
1864 	/* reg the rmb */
1865 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
1866 		return SMC_CLC_DECL_ERR_REGBUF;
1867 
1868 	/* send CONFIRM LINK request to client over the RoCE fabric */
1869 	rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1870 	if (rc < 0)
1871 		return SMC_CLC_DECL_TIMEOUT_CL;
1872 
1873 	/* receive CONFIRM LINK response from client over the RoCE fabric */
1874 	qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1875 			      SMC_LLC_CONFIRM_LINK);
1876 	if (!qentry) {
1877 		struct smc_clc_msg_decline dclc;
1878 
1879 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1880 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1881 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1882 	}
1883 	smc_llc_save_peer_uid(qentry);
1884 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1885 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1886 	if (rc)
1887 		return SMC_CLC_DECL_RMBE_EC;
1888 
1889 	/* confirm_rkey is implicit on 1st contact */
1890 	smc->conn.rmb_desc->is_conf_rkey = true;
1891 
1892 	smc_llc_link_active(link);
1893 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1894 
1895 	if (link->lgr->max_links > 1) {
1896 		down_write(&link->lgr->llc_conf_mutex);
1897 		/* initial contact - try to establish second link */
1898 		smc_llc_srv_add_link(link, NULL);
1899 		up_write(&link->lgr->llc_conf_mutex);
1900 	}
1901 	return 0;
1902 }
1903 
1904 /* listen worker: finish */
1905 static void smc_listen_out(struct smc_sock *new_smc)
1906 {
1907 	struct smc_sock *lsmc = new_smc->listen_smc;
1908 	struct sock *newsmcsk = &new_smc->sk;
1909 
1910 	if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1911 		atomic_dec(&lsmc->queued_smc_hs);
1912 
1913 	if (lsmc->sk.sk_state == SMC_LISTEN) {
1914 		lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1915 		smc_accept_enqueue(&lsmc->sk, newsmcsk);
1916 		release_sock(&lsmc->sk);
1917 	} else { /* no longer listening */
1918 		smc_close_non_accepted(newsmcsk);
1919 	}
1920 
1921 	/* Wake up accept */
1922 	lsmc->sk.sk_data_ready(&lsmc->sk);
1923 	sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1924 }
1925 
1926 /* listen worker: finish in state connected */
1927 static void smc_listen_out_connected(struct smc_sock *new_smc)
1928 {
1929 	struct sock *newsmcsk = &new_smc->sk;
1930 
1931 	if (newsmcsk->sk_state == SMC_INIT)
1932 		newsmcsk->sk_state = SMC_ACTIVE;
1933 
1934 	smc_listen_out(new_smc);
1935 }
1936 
1937 /* listen worker: finish in error state */
1938 static void smc_listen_out_err(struct smc_sock *new_smc)
1939 {
1940 	struct sock *newsmcsk = &new_smc->sk;
1941 	struct net *net = sock_net(newsmcsk);
1942 
1943 	this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1944 	if (newsmcsk->sk_state == SMC_INIT)
1945 		sock_put(&new_smc->sk); /* passive closing */
1946 	newsmcsk->sk_state = SMC_CLOSED;
1947 
1948 	smc_listen_out(new_smc);
1949 }
1950 
1951 /* listen worker: decline and fall back if possible */
1952 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1953 			       int local_first, u8 version)
1954 {
1955 	/* RDMA setup failed, switch back to TCP */
1956 	smc_conn_abort(new_smc, local_first);
1957 	if (reason_code < 0 ||
1958 	    smc_switch_to_fallback(new_smc, reason_code)) {
1959 		/* error, no fallback possible */
1960 		smc_listen_out_err(new_smc);
1961 		return;
1962 	}
1963 	if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1964 		if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1965 			smc_listen_out_err(new_smc);
1966 			return;
1967 		}
1968 	}
1969 	smc_listen_out_connected(new_smc);
1970 }
1971 
1972 /* listen worker: version checking */
1973 static int smc_listen_v2_check(struct smc_sock *new_smc,
1974 			       struct smc_clc_msg_proposal *pclc,
1975 			       struct smc_init_info *ini)
1976 {
1977 	struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1978 	struct smc_clc_v2_extension *pclc_v2_ext;
1979 	int rc = SMC_CLC_DECL_PEERNOSMC;
1980 
1981 	ini->smc_type_v1 = pclc->hdr.typev1;
1982 	ini->smc_type_v2 = pclc->hdr.typev2;
1983 	ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1984 	ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1985 	if (pclc->hdr.version > SMC_V1) {
1986 		if (smcd_indicated(ini->smc_type_v2))
1987 			ini->smcd_version |= SMC_V2;
1988 		if (smcr_indicated(ini->smc_type_v2))
1989 			ini->smcr_version |= SMC_V2;
1990 	}
1991 	if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1992 		rc = SMC_CLC_DECL_PEERNOSMC;
1993 		goto out;
1994 	}
1995 	pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1996 	if (!pclc_v2_ext) {
1997 		ini->smcd_version &= ~SMC_V2;
1998 		ini->smcr_version &= ~SMC_V2;
1999 		rc = SMC_CLC_DECL_NOV2EXT;
2000 		goto out;
2001 	}
2002 	pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
2003 	if (ini->smcd_version & SMC_V2) {
2004 		if (!smc_ism_is_v2_capable()) {
2005 			ini->smcd_version &= ~SMC_V2;
2006 			rc = SMC_CLC_DECL_NOISM2SUPP;
2007 		} else if (!pclc_smcd_v2_ext) {
2008 			ini->smcd_version &= ~SMC_V2;
2009 			rc = SMC_CLC_DECL_NOV2DEXT;
2010 		} else if (!pclc_v2_ext->hdr.eid_cnt &&
2011 			   !pclc_v2_ext->hdr.flag.seid) {
2012 			ini->smcd_version &= ~SMC_V2;
2013 			rc = SMC_CLC_DECL_NOUEID;
2014 		}
2015 	}
2016 	if (ini->smcr_version & SMC_V2) {
2017 		if (!pclc_v2_ext->hdr.eid_cnt) {
2018 			ini->smcr_version &= ~SMC_V2;
2019 			rc = SMC_CLC_DECL_NOUEID;
2020 		}
2021 	}
2022 
2023 	ini->release_nr = pclc_v2_ext->hdr.flag.release;
2024 	if (pclc_v2_ext->hdr.flag.release > SMC_RELEASE)
2025 		ini->release_nr = SMC_RELEASE;
2026 
2027 out:
2028 	if (!ini->smcd_version && !ini->smcr_version)
2029 		return rc;
2030 
2031 	return 0;
2032 }
2033 
2034 /* listen worker: check prefixes */
2035 static int smc_listen_prfx_check(struct smc_sock *new_smc,
2036 				 struct smc_clc_msg_proposal *pclc)
2037 {
2038 	struct smc_clc_msg_proposal_prefix *pclc_prfx;
2039 	struct socket *newclcsock = new_smc->clcsock;
2040 
2041 	if (pclc->hdr.typev1 == SMC_TYPE_N)
2042 		return 0;
2043 	pclc_prfx = smc_clc_proposal_get_prefix(pclc);
2044 	if (smc_clc_prfx_match(newclcsock, pclc_prfx))
2045 		return SMC_CLC_DECL_DIFFPREFIX;
2046 
2047 	return 0;
2048 }
2049 
2050 /* listen worker: initialize connection and buffers */
2051 static int smc_listen_rdma_init(struct smc_sock *new_smc,
2052 				struct smc_init_info *ini)
2053 {
2054 	int rc;
2055 
2056 	/* allocate connection / link group */
2057 	rc = smc_conn_create(new_smc, ini);
2058 	if (rc)
2059 		return rc;
2060 
2061 	/* create send buffer and rmb */
2062 	if (smc_buf_create(new_smc, false)) {
2063 		smc_conn_abort(new_smc, ini->first_contact_local);
2064 		return SMC_CLC_DECL_MEM;
2065 	}
2066 
2067 	return 0;
2068 }
2069 
2070 /* listen worker: initialize connection and buffers for SMC-D */
2071 static int smc_listen_ism_init(struct smc_sock *new_smc,
2072 			       struct smc_init_info *ini)
2073 {
2074 	int rc;
2075 
2076 	rc = smc_conn_create(new_smc, ini);
2077 	if (rc)
2078 		return rc;
2079 
2080 	/* Create send and receive buffers */
2081 	rc = smc_buf_create(new_smc, true);
2082 	if (rc) {
2083 		smc_conn_abort(new_smc, ini->first_contact_local);
2084 		return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2085 					 SMC_CLC_DECL_MEM;
2086 	}
2087 
2088 	return 0;
2089 }
2090 
2091 static bool smc_is_already_selected(struct smcd_dev *smcd,
2092 				    struct smc_init_info *ini,
2093 				    int matches)
2094 {
2095 	int i;
2096 
2097 	for (i = 0; i < matches; i++)
2098 		if (smcd == ini->ism_dev[i])
2099 			return true;
2100 
2101 	return false;
2102 }
2103 
2104 /* check for ISM devices matching proposed ISM devices */
2105 static void smc_check_ism_v2_match(struct smc_init_info *ini,
2106 				   u16 proposed_chid,
2107 				   struct smcd_gid *proposed_gid,
2108 				   unsigned int *matches)
2109 {
2110 	struct smcd_dev *smcd;
2111 
2112 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2113 		if (smcd->going_away)
2114 			continue;
2115 		if (smc_is_already_selected(smcd, ini, *matches))
2116 			continue;
2117 		if (smc_ism_get_chid(smcd) == proposed_chid &&
2118 		    !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2119 			ini->ism_peer_gid[*matches].gid = proposed_gid->gid;
2120 			if (__smc_ism_is_virtual(proposed_chid))
2121 				ini->ism_peer_gid[*matches].gid_ext =
2122 							proposed_gid->gid_ext;
2123 				/* non-virtual ISM's peer gid_ext remains 0. */
2124 			ini->ism_dev[*matches] = smcd;
2125 			(*matches)++;
2126 			break;
2127 		}
2128 	}
2129 }
2130 
2131 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2132 {
2133 	if (!ini->rc)
2134 		ini->rc = rc;
2135 }
2136 
2137 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2138 					struct smc_clc_msg_proposal *pclc,
2139 					struct smc_init_info *ini)
2140 {
2141 	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2142 	struct smc_clc_v2_extension *smc_v2_ext;
2143 	struct smc_clc_msg_smcd *pclc_smcd;
2144 	unsigned int matches = 0;
2145 	struct smcd_gid smcd_gid;
2146 	u8 smcd_version;
2147 	u8 *eid = NULL;
2148 	int i, rc;
2149 	u16 chid;
2150 
2151 	if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2152 		goto not_found;
2153 
2154 	pclc_smcd = smc_get_clc_msg_smcd(pclc);
2155 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2156 	smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2157 
2158 	mutex_lock(&smcd_dev_list.mutex);
2159 	if (pclc_smcd->ism.chid) {
2160 		/* check for ISM device matching proposed native ISM device */
2161 		smcd_gid.gid = ntohll(pclc_smcd->ism.gid);
2162 		smcd_gid.gid_ext = 0;
2163 		smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2164 				       &smcd_gid, &matches);
2165 	}
2166 	for (i = 0; i < smc_v2_ext->hdr.ism_gid_cnt; i++) {
2167 		/* check for ISM devices matching proposed non-native ISM
2168 		 * devices
2169 		 */
2170 		smcd_gid.gid = ntohll(smcd_v2_ext->gidchid[i].gid);
2171 		smcd_gid.gid_ext = 0;
2172 		chid = ntohs(smcd_v2_ext->gidchid[i].chid);
2173 		if (__smc_ism_is_virtual(chid)) {
2174 			if ((i + 1) == smc_v2_ext->hdr.ism_gid_cnt ||
2175 			    chid != ntohs(smcd_v2_ext->gidchid[i + 1].chid))
2176 				/* each virtual ISM device takes two GID-CHID
2177 				 * entries and CHID of the second entry repeats
2178 				 * that of the first entry.
2179 				 *
2180 				 * So check if the next GID-CHID entry exists
2181 				 * and both two entries' CHIDs are the same.
2182 				 */
2183 				continue;
2184 			smcd_gid.gid_ext =
2185 				ntohll(smcd_v2_ext->gidchid[++i].gid);
2186 		}
2187 		smc_check_ism_v2_match(ini, chid, &smcd_gid, &matches);
2188 	}
2189 	mutex_unlock(&smcd_dev_list.mutex);
2190 
2191 	if (!ini->ism_dev[0]) {
2192 		smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2193 		goto not_found;
2194 	}
2195 
2196 	smc_ism_get_system_eid(&eid);
2197 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2198 			       smcd_v2_ext->system_eid, eid))
2199 		goto not_found;
2200 
2201 	/* separate - outside the smcd_dev_list.lock */
2202 	smcd_version = ini->smcd_version;
2203 	for (i = 0; i < matches; i++) {
2204 		ini->smcd_version = SMC_V2;
2205 		ini->is_smcd = true;
2206 		ini->ism_selected = i;
2207 		rc = smc_listen_ism_init(new_smc, ini);
2208 		if (rc) {
2209 			smc_find_ism_store_rc(rc, ini);
2210 			/* try next active ISM device */
2211 			continue;
2212 		}
2213 		return; /* matching and usable V2 ISM device found */
2214 	}
2215 	/* no V2 ISM device could be initialized */
2216 	ini->smcd_version = smcd_version;	/* restore original value */
2217 	ini->negotiated_eid[0] = 0;
2218 
2219 not_found:
2220 	ini->smcd_version &= ~SMC_V2;
2221 	ini->ism_dev[0] = NULL;
2222 	ini->is_smcd = false;
2223 }
2224 
2225 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2226 					struct smc_clc_msg_proposal *pclc,
2227 					struct smc_init_info *ini)
2228 {
2229 	struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2230 	int rc = 0;
2231 
2232 	/* check if ISM V1 is available */
2233 	if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2234 		goto not_found;
2235 	ini->is_smcd = true; /* prepare ISM check */
2236 	ini->ism_peer_gid[0].gid = ntohll(pclc_smcd->ism.gid);
2237 	ini->ism_peer_gid[0].gid_ext = 0;
2238 	rc = smc_find_ism_device(new_smc, ini);
2239 	if (rc)
2240 		goto not_found;
2241 	ini->ism_selected = 0;
2242 	rc = smc_listen_ism_init(new_smc, ini);
2243 	if (!rc)
2244 		return;		/* V1 ISM device found */
2245 
2246 not_found:
2247 	smc_find_ism_store_rc(rc, ini);
2248 	ini->smcd_version &= ~SMC_V1;
2249 	ini->ism_dev[0] = NULL;
2250 	ini->is_smcd = false;
2251 }
2252 
2253 /* listen worker: register buffers */
2254 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2255 {
2256 	struct smc_connection *conn = &new_smc->conn;
2257 
2258 	if (!local_first) {
2259 		/* reg sendbufs if they were vzalloced */
2260 		if (conn->sndbuf_desc->is_vm) {
2261 			if (smcr_lgr_reg_sndbufs(conn->lnk,
2262 						 conn->sndbuf_desc))
2263 				return SMC_CLC_DECL_ERR_REGBUF;
2264 		}
2265 		if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2266 			return SMC_CLC_DECL_ERR_REGBUF;
2267 	}
2268 
2269 	return 0;
2270 }
2271 
2272 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2273 					 struct smc_clc_msg_proposal *pclc,
2274 					 struct smc_init_info *ini)
2275 {
2276 	struct smc_clc_v2_extension *smc_v2_ext;
2277 	u8 smcr_version;
2278 	int rc;
2279 
2280 	if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2281 		goto not_found;
2282 
2283 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2284 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2285 		goto not_found;
2286 
2287 	/* prepare RDMA check */
2288 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2289 	memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2290 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2291 	ini->check_smcrv2 = true;
2292 	ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2293 	ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2294 	ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2295 	rc = smc_find_rdma_device(new_smc, ini);
2296 	if (rc) {
2297 		smc_find_ism_store_rc(rc, ini);
2298 		goto not_found;
2299 	}
2300 	if (!ini->smcrv2.uses_gateway)
2301 		memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2302 
2303 	smcr_version = ini->smcr_version;
2304 	ini->smcr_version = SMC_V2;
2305 	rc = smc_listen_rdma_init(new_smc, ini);
2306 	if (!rc) {
2307 		rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2308 		if (rc)
2309 			smc_conn_abort(new_smc, ini->first_contact_local);
2310 	}
2311 	if (!rc)
2312 		return;
2313 	ini->smcr_version = smcr_version;
2314 	smc_find_ism_store_rc(rc, ini);
2315 
2316 not_found:
2317 	ini->smcr_version &= ~SMC_V2;
2318 	ini->smcrv2.ib_dev_v2 = NULL;
2319 	ini->check_smcrv2 = false;
2320 }
2321 
2322 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2323 					struct smc_clc_msg_proposal *pclc,
2324 					struct smc_init_info *ini)
2325 {
2326 	int rc;
2327 
2328 	if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2329 		return SMC_CLC_DECL_NOSMCDEV;
2330 
2331 	/* prepare RDMA check */
2332 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2333 	memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2334 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2335 	rc = smc_find_rdma_device(new_smc, ini);
2336 	if (rc) {
2337 		/* no RDMA device found */
2338 		return SMC_CLC_DECL_NOSMCDEV;
2339 	}
2340 	rc = smc_listen_rdma_init(new_smc, ini);
2341 	if (rc)
2342 		return rc;
2343 	return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2344 }
2345 
2346 /* determine the local device matching to proposal */
2347 static int smc_listen_find_device(struct smc_sock *new_smc,
2348 				  struct smc_clc_msg_proposal *pclc,
2349 				  struct smc_init_info *ini)
2350 {
2351 	int prfx_rc;
2352 
2353 	/* check for ISM device matching V2 proposed device */
2354 	smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2355 	if (ini->ism_dev[0])
2356 		return 0;
2357 
2358 	/* check for matching IP prefix and subnet length (V1) */
2359 	prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2360 	if (prfx_rc)
2361 		smc_find_ism_store_rc(prfx_rc, ini);
2362 
2363 	/* get vlan id from IP device */
2364 	if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2365 		return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2366 
2367 	/* check for ISM device matching V1 proposed device */
2368 	if (!prfx_rc)
2369 		smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2370 	if (ini->ism_dev[0])
2371 		return 0;
2372 
2373 	if (!smcr_indicated(pclc->hdr.typev1) &&
2374 	    !smcr_indicated(pclc->hdr.typev2))
2375 		/* skip RDMA and decline */
2376 		return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2377 
2378 	/* check if RDMA V2 is available */
2379 	smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2380 	if (ini->smcrv2.ib_dev_v2)
2381 		return 0;
2382 
2383 	/* check if RDMA V1 is available */
2384 	if (!prfx_rc) {
2385 		int rc;
2386 
2387 		rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2388 		smc_find_ism_store_rc(rc, ini);
2389 		return (!rc) ? 0 : ini->rc;
2390 	}
2391 	return prfx_rc;
2392 }
2393 
2394 /* listen worker: finish RDMA setup */
2395 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2396 				  struct smc_clc_msg_accept_confirm *cclc,
2397 				  bool local_first,
2398 				  struct smc_init_info *ini)
2399 {
2400 	struct smc_link *link = new_smc->conn.lnk;
2401 	int reason_code = 0;
2402 
2403 	if (local_first)
2404 		smc_link_save_peer_info(link, cclc, ini);
2405 
2406 	if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2407 		return SMC_CLC_DECL_ERR_RTOK;
2408 
2409 	if (local_first) {
2410 		if (smc_ib_ready_link(link))
2411 			return SMC_CLC_DECL_ERR_RDYLNK;
2412 		/* QP confirmation over RoCE fabric */
2413 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2414 		reason_code = smcr_serv_conf_first_link(new_smc);
2415 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2416 	}
2417 	return reason_code;
2418 }
2419 
2420 /* setup for connection of server */
2421 static void smc_listen_work(struct work_struct *work)
2422 {
2423 	struct smc_sock *new_smc = container_of(work, struct smc_sock,
2424 						smc_listen_work);
2425 	struct socket *newclcsock = new_smc->clcsock;
2426 	struct smc_clc_msg_accept_confirm *cclc;
2427 	struct smc_clc_msg_proposal_area *buf;
2428 	struct smc_clc_msg_proposal *pclc;
2429 	struct smc_init_info *ini = NULL;
2430 	u8 proposal_version = SMC_V1;
2431 	u8 accept_version;
2432 	int rc = 0;
2433 
2434 	if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2435 		return smc_listen_out_err(new_smc);
2436 
2437 	if (new_smc->use_fallback) {
2438 		smc_listen_out_connected(new_smc);
2439 		return;
2440 	}
2441 
2442 	/* check if peer is smc capable */
2443 	if (!tcp_sk(newclcsock->sk)->syn_smc) {
2444 		rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2445 		if (rc)
2446 			smc_listen_out_err(new_smc);
2447 		else
2448 			smc_listen_out_connected(new_smc);
2449 		return;
2450 	}
2451 
2452 	/* do inband token exchange -
2453 	 * wait for and receive SMC Proposal CLC message
2454 	 */
2455 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2456 	if (!buf) {
2457 		rc = SMC_CLC_DECL_MEM;
2458 		goto out_decl;
2459 	}
2460 	pclc = (struct smc_clc_msg_proposal *)buf;
2461 	rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2462 			      SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2463 	if (rc)
2464 		goto out_decl;
2465 
2466 	if (pclc->hdr.version > SMC_V1)
2467 		proposal_version = SMC_V2;
2468 
2469 	/* IPSec connections opt out of SMC optimizations */
2470 	if (using_ipsec(new_smc)) {
2471 		rc = SMC_CLC_DECL_IPSEC;
2472 		goto out_decl;
2473 	}
2474 
2475 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2476 	if (!ini) {
2477 		rc = SMC_CLC_DECL_MEM;
2478 		goto out_decl;
2479 	}
2480 
2481 	/* initial version checking */
2482 	rc = smc_listen_v2_check(new_smc, pclc, ini);
2483 	if (rc)
2484 		goto out_decl;
2485 
2486 	rc = smc_clc_srv_v2x_features_validate(new_smc, pclc, ini);
2487 	if (rc)
2488 		goto out_decl;
2489 
2490 	mutex_lock(&smc_server_lgr_pending);
2491 	smc_close_init(new_smc);
2492 	smc_rx_init(new_smc);
2493 	smc_tx_init(new_smc);
2494 
2495 	/* determine ISM or RoCE device used for connection */
2496 	rc = smc_listen_find_device(new_smc, pclc, ini);
2497 	if (rc)
2498 		goto out_unlock;
2499 
2500 	/* send SMC Accept CLC message */
2501 	accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2502 	rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2503 				 accept_version, ini->negotiated_eid, ini);
2504 	if (rc)
2505 		goto out_unlock;
2506 
2507 	/* SMC-D does not need this lock any more */
2508 	if (ini->is_smcd)
2509 		mutex_unlock(&smc_server_lgr_pending);
2510 
2511 	/* receive SMC Confirm CLC message */
2512 	memset(buf, 0, sizeof(*buf));
2513 	cclc = (struct smc_clc_msg_accept_confirm *)buf;
2514 	rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2515 			      SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2516 	if (rc) {
2517 		if (!ini->is_smcd)
2518 			goto out_unlock;
2519 		goto out_decl;
2520 	}
2521 
2522 	rc = smc_clc_v2x_features_confirm_check(cclc, ini);
2523 	if (rc) {
2524 		if (!ini->is_smcd)
2525 			goto out_unlock;
2526 		goto out_decl;
2527 	}
2528 
2529 	/* fce smc release version is needed in smc_listen_rdma_finish,
2530 	 * so save fce info here.
2531 	 */
2532 	smc_conn_save_peer_info_fce(new_smc, cclc);
2533 
2534 	/* finish worker */
2535 	if (!ini->is_smcd) {
2536 		rc = smc_listen_rdma_finish(new_smc, cclc,
2537 					    ini->first_contact_local, ini);
2538 		if (rc)
2539 			goto out_unlock;
2540 		mutex_unlock(&smc_server_lgr_pending);
2541 	}
2542 	smc_conn_save_peer_info(new_smc, cclc);
2543 	smc_listen_out_connected(new_smc);
2544 	SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2545 	goto out_free;
2546 
2547 out_unlock:
2548 	mutex_unlock(&smc_server_lgr_pending);
2549 out_decl:
2550 	smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2551 			   proposal_version);
2552 out_free:
2553 	kfree(ini);
2554 	kfree(buf);
2555 }
2556 
2557 static void smc_tcp_listen_work(struct work_struct *work)
2558 {
2559 	struct smc_sock *lsmc = container_of(work, struct smc_sock,
2560 					     tcp_listen_work);
2561 	struct sock *lsk = &lsmc->sk;
2562 	struct smc_sock *new_smc;
2563 	int rc = 0;
2564 
2565 	lock_sock(lsk);
2566 	while (lsk->sk_state == SMC_LISTEN) {
2567 		rc = smc_clcsock_accept(lsmc, &new_smc);
2568 		if (rc) /* clcsock accept queue empty or error */
2569 			goto out;
2570 		if (!new_smc)
2571 			continue;
2572 
2573 		if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2574 			atomic_inc(&lsmc->queued_smc_hs);
2575 
2576 		new_smc->listen_smc = lsmc;
2577 		new_smc->use_fallback = lsmc->use_fallback;
2578 		new_smc->fallback_rsn = lsmc->fallback_rsn;
2579 		sock_hold(lsk); /* sock_put in smc_listen_work */
2580 		INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2581 		smc_copy_sock_settings_to_smc(new_smc);
2582 		sock_hold(&new_smc->sk); /* sock_put in passive closing */
2583 		if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2584 			sock_put(&new_smc->sk);
2585 	}
2586 
2587 out:
2588 	release_sock(lsk);
2589 	sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2590 }
2591 
2592 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2593 {
2594 	struct smc_sock *lsmc;
2595 
2596 	read_lock_bh(&listen_clcsock->sk_callback_lock);
2597 	lsmc = smc_clcsock_user_data(listen_clcsock);
2598 	if (!lsmc)
2599 		goto out;
2600 	lsmc->clcsk_data_ready(listen_clcsock);
2601 	if (lsmc->sk.sk_state == SMC_LISTEN) {
2602 		sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2603 		if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2604 			sock_put(&lsmc->sk);
2605 	}
2606 out:
2607 	read_unlock_bh(&listen_clcsock->sk_callback_lock);
2608 }
2609 
2610 static int smc_listen(struct socket *sock, int backlog)
2611 {
2612 	struct sock *sk = sock->sk;
2613 	struct smc_sock *smc;
2614 	int rc;
2615 
2616 	smc = smc_sk(sk);
2617 	lock_sock(sk);
2618 
2619 	rc = -EINVAL;
2620 	if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2621 	    smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2622 		goto out;
2623 
2624 	rc = 0;
2625 	if (sk->sk_state == SMC_LISTEN) {
2626 		sk->sk_max_ack_backlog = backlog;
2627 		goto out;
2628 	}
2629 	/* some socket options are handled in core, so we could not apply
2630 	 * them to the clc socket -- copy smc socket options to clc socket
2631 	 */
2632 	smc_copy_sock_settings_to_clc(smc);
2633 	if (!smc->use_fallback)
2634 		tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2635 
2636 	/* save original sk_data_ready function and establish
2637 	 * smc-specific sk_data_ready function
2638 	 */
2639 	write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2640 	smc->clcsock->sk->sk_user_data =
2641 		(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2642 	smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2643 			       smc_clcsock_data_ready, &smc->clcsk_data_ready);
2644 	write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2645 
2646 	/* save original ops */
2647 	smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2648 
2649 	smc->af_ops = *smc->ori_af_ops;
2650 	smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2651 
2652 	inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2653 
2654 	if (smc->limit_smc_hs)
2655 		tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2656 
2657 	rc = kernel_listen(smc->clcsock, backlog);
2658 	if (rc) {
2659 		write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2660 		smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2661 				       &smc->clcsk_data_ready);
2662 		smc->clcsock->sk->sk_user_data = NULL;
2663 		write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2664 		goto out;
2665 	}
2666 	sk->sk_max_ack_backlog = backlog;
2667 	sk->sk_ack_backlog = 0;
2668 	sk->sk_state = SMC_LISTEN;
2669 
2670 out:
2671 	release_sock(sk);
2672 	return rc;
2673 }
2674 
2675 static int smc_accept(struct socket *sock, struct socket *new_sock,
2676 		      int flags, bool kern)
2677 {
2678 	struct sock *sk = sock->sk, *nsk;
2679 	DECLARE_WAITQUEUE(wait, current);
2680 	struct smc_sock *lsmc;
2681 	long timeo;
2682 	int rc = 0;
2683 
2684 	lsmc = smc_sk(sk);
2685 	sock_hold(sk); /* sock_put below */
2686 	lock_sock(sk);
2687 
2688 	if (lsmc->sk.sk_state != SMC_LISTEN) {
2689 		rc = -EINVAL;
2690 		release_sock(sk);
2691 		goto out;
2692 	}
2693 
2694 	/* Wait for an incoming connection */
2695 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2696 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
2697 	while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2698 		set_current_state(TASK_INTERRUPTIBLE);
2699 		if (!timeo) {
2700 			rc = -EAGAIN;
2701 			break;
2702 		}
2703 		release_sock(sk);
2704 		timeo = schedule_timeout(timeo);
2705 		/* wakeup by sk_data_ready in smc_listen_work() */
2706 		sched_annotate_sleep();
2707 		lock_sock(sk);
2708 		if (signal_pending(current)) {
2709 			rc = sock_intr_errno(timeo);
2710 			break;
2711 		}
2712 	}
2713 	set_current_state(TASK_RUNNING);
2714 	remove_wait_queue(sk_sleep(sk), &wait);
2715 
2716 	if (!rc)
2717 		rc = sock_error(nsk);
2718 	release_sock(sk);
2719 	if (rc)
2720 		goto out;
2721 
2722 	if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
2723 		/* wait till data arrives on the socket */
2724 		timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2725 								MSEC_PER_SEC);
2726 		if (smc_sk(nsk)->use_fallback) {
2727 			struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2728 
2729 			lock_sock(clcsk);
2730 			if (skb_queue_empty(&clcsk->sk_receive_queue))
2731 				sk_wait_data(clcsk, &timeo, NULL);
2732 			release_sock(clcsk);
2733 		} else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2734 			lock_sock(nsk);
2735 			smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2736 			release_sock(nsk);
2737 		}
2738 	}
2739 
2740 out:
2741 	sock_put(sk); /* sock_hold above */
2742 	return rc;
2743 }
2744 
2745 static int smc_getname(struct socket *sock, struct sockaddr *addr,
2746 		       int peer)
2747 {
2748 	struct smc_sock *smc;
2749 
2750 	if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2751 	    (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2752 		return -ENOTCONN;
2753 
2754 	smc = smc_sk(sock->sk);
2755 
2756 	return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2757 }
2758 
2759 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2760 {
2761 	struct sock *sk = sock->sk;
2762 	struct smc_sock *smc;
2763 	int rc;
2764 
2765 	smc = smc_sk(sk);
2766 	lock_sock(sk);
2767 
2768 	/* SMC does not support connect with fastopen */
2769 	if (msg->msg_flags & MSG_FASTOPEN) {
2770 		/* not connected yet, fallback */
2771 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2772 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2773 			if (rc)
2774 				goto out;
2775 		} else {
2776 			rc = -EINVAL;
2777 			goto out;
2778 		}
2779 	} else if ((sk->sk_state != SMC_ACTIVE) &&
2780 		   (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2781 		   (sk->sk_state != SMC_INIT)) {
2782 		rc = -EPIPE;
2783 		goto out;
2784 	}
2785 
2786 	if (smc->use_fallback) {
2787 		rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2788 	} else {
2789 		rc = smc_tx_sendmsg(smc, msg, len);
2790 		SMC_STAT_TX_PAYLOAD(smc, len, rc);
2791 	}
2792 out:
2793 	release_sock(sk);
2794 	return rc;
2795 }
2796 
2797 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2798 		       int flags)
2799 {
2800 	struct sock *sk = sock->sk;
2801 	struct smc_sock *smc;
2802 	int rc = -ENOTCONN;
2803 
2804 	smc = smc_sk(sk);
2805 	lock_sock(sk);
2806 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2807 		/* socket was connected before, no more data to read */
2808 		rc = 0;
2809 		goto out;
2810 	}
2811 	if ((sk->sk_state == SMC_INIT) ||
2812 	    (sk->sk_state == SMC_LISTEN) ||
2813 	    (sk->sk_state == SMC_CLOSED))
2814 		goto out;
2815 
2816 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2817 		rc = 0;
2818 		goto out;
2819 	}
2820 
2821 	if (smc->use_fallback) {
2822 		rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2823 	} else {
2824 		msg->msg_namelen = 0;
2825 		rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2826 		SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2827 	}
2828 
2829 out:
2830 	release_sock(sk);
2831 	return rc;
2832 }
2833 
2834 static __poll_t smc_accept_poll(struct sock *parent)
2835 {
2836 	struct smc_sock *isk = smc_sk(parent);
2837 	__poll_t mask = 0;
2838 
2839 	spin_lock(&isk->accept_q_lock);
2840 	if (!list_empty(&isk->accept_q))
2841 		mask = EPOLLIN | EPOLLRDNORM;
2842 	spin_unlock(&isk->accept_q_lock);
2843 
2844 	return mask;
2845 }
2846 
2847 static __poll_t smc_poll(struct file *file, struct socket *sock,
2848 			     poll_table *wait)
2849 {
2850 	struct sock *sk = sock->sk;
2851 	struct smc_sock *smc;
2852 	__poll_t mask = 0;
2853 
2854 	if (!sk)
2855 		return EPOLLNVAL;
2856 
2857 	smc = smc_sk(sock->sk);
2858 	if (smc->use_fallback) {
2859 		/* delegate to CLC child sock */
2860 		mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2861 		sk->sk_err = smc->clcsock->sk->sk_err;
2862 	} else {
2863 		if (sk->sk_state != SMC_CLOSED)
2864 			sock_poll_wait(file, sock, wait);
2865 		if (sk->sk_err)
2866 			mask |= EPOLLERR;
2867 		if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2868 		    (sk->sk_state == SMC_CLOSED))
2869 			mask |= EPOLLHUP;
2870 		if (sk->sk_state == SMC_LISTEN) {
2871 			/* woken up by sk_data_ready in smc_listen_work() */
2872 			mask |= smc_accept_poll(sk);
2873 		} else if (smc->use_fallback) { /* as result of connect_work()*/
2874 			mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2875 							   wait);
2876 			sk->sk_err = smc->clcsock->sk->sk_err;
2877 		} else {
2878 			if ((sk->sk_state != SMC_INIT &&
2879 			     atomic_read(&smc->conn.sndbuf_space)) ||
2880 			    sk->sk_shutdown & SEND_SHUTDOWN) {
2881 				mask |= EPOLLOUT | EPOLLWRNORM;
2882 			} else {
2883 				sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2884 				set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2885 			}
2886 			if (atomic_read(&smc->conn.bytes_to_rcv))
2887 				mask |= EPOLLIN | EPOLLRDNORM;
2888 			if (sk->sk_shutdown & RCV_SHUTDOWN)
2889 				mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2890 			if (sk->sk_state == SMC_APPCLOSEWAIT1)
2891 				mask |= EPOLLIN;
2892 			if (smc->conn.urg_state == SMC_URG_VALID)
2893 				mask |= EPOLLPRI;
2894 		}
2895 	}
2896 
2897 	return mask;
2898 }
2899 
2900 static int smc_shutdown(struct socket *sock, int how)
2901 {
2902 	struct sock *sk = sock->sk;
2903 	bool do_shutdown = true;
2904 	struct smc_sock *smc;
2905 	int rc = -EINVAL;
2906 	int old_state;
2907 	int rc1 = 0;
2908 
2909 	smc = smc_sk(sk);
2910 
2911 	if ((how < SHUT_RD) || (how > SHUT_RDWR))
2912 		return rc;
2913 
2914 	lock_sock(sk);
2915 
2916 	if (sock->state == SS_CONNECTING) {
2917 		if (sk->sk_state == SMC_ACTIVE)
2918 			sock->state = SS_CONNECTED;
2919 		else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2920 			 sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2921 			 sk->sk_state == SMC_APPCLOSEWAIT1 ||
2922 			 sk->sk_state == SMC_APPCLOSEWAIT2 ||
2923 			 sk->sk_state == SMC_APPFINCLOSEWAIT)
2924 			sock->state = SS_DISCONNECTING;
2925 	}
2926 
2927 	rc = -ENOTCONN;
2928 	if ((sk->sk_state != SMC_ACTIVE) &&
2929 	    (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2930 	    (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2931 	    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2932 	    (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2933 	    (sk->sk_state != SMC_APPFINCLOSEWAIT))
2934 		goto out;
2935 	if (smc->use_fallback) {
2936 		rc = kernel_sock_shutdown(smc->clcsock, how);
2937 		sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2938 		if (sk->sk_shutdown == SHUTDOWN_MASK) {
2939 			sk->sk_state = SMC_CLOSED;
2940 			sk->sk_socket->state = SS_UNCONNECTED;
2941 			sock_put(sk);
2942 		}
2943 		goto out;
2944 	}
2945 	switch (how) {
2946 	case SHUT_RDWR:		/* shutdown in both directions */
2947 		old_state = sk->sk_state;
2948 		rc = smc_close_active(smc);
2949 		if (old_state == SMC_ACTIVE &&
2950 		    sk->sk_state == SMC_PEERCLOSEWAIT1)
2951 			do_shutdown = false;
2952 		break;
2953 	case SHUT_WR:
2954 		rc = smc_close_shutdown_write(smc);
2955 		break;
2956 	case SHUT_RD:
2957 		rc = 0;
2958 		/* nothing more to do because peer is not involved */
2959 		break;
2960 	}
2961 	if (do_shutdown && smc->clcsock)
2962 		rc1 = kernel_sock_shutdown(smc->clcsock, how);
2963 	/* map sock_shutdown_cmd constants to sk_shutdown value range */
2964 	sk->sk_shutdown |= how + 1;
2965 
2966 	if (sk->sk_state == SMC_CLOSED)
2967 		sock->state = SS_UNCONNECTED;
2968 	else
2969 		sock->state = SS_DISCONNECTING;
2970 out:
2971 	release_sock(sk);
2972 	return rc ? rc : rc1;
2973 }
2974 
2975 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2976 			    char __user *optval, int __user *optlen)
2977 {
2978 	struct smc_sock *smc;
2979 	int val, len;
2980 
2981 	smc = smc_sk(sock->sk);
2982 
2983 	if (get_user(len, optlen))
2984 		return -EFAULT;
2985 
2986 	len = min_t(int, len, sizeof(int));
2987 
2988 	if (len < 0)
2989 		return -EINVAL;
2990 
2991 	switch (optname) {
2992 	case SMC_LIMIT_HS:
2993 		val = smc->limit_smc_hs;
2994 		break;
2995 	default:
2996 		return -EOPNOTSUPP;
2997 	}
2998 
2999 	if (put_user(len, optlen))
3000 		return -EFAULT;
3001 	if (copy_to_user(optval, &val, len))
3002 		return -EFAULT;
3003 
3004 	return 0;
3005 }
3006 
3007 static int __smc_setsockopt(struct socket *sock, int level, int optname,
3008 			    sockptr_t optval, unsigned int optlen)
3009 {
3010 	struct sock *sk = sock->sk;
3011 	struct smc_sock *smc;
3012 	int val, rc;
3013 
3014 	smc = smc_sk(sk);
3015 
3016 	lock_sock(sk);
3017 	switch (optname) {
3018 	case SMC_LIMIT_HS:
3019 		if (optlen < sizeof(int)) {
3020 			rc = -EINVAL;
3021 			break;
3022 		}
3023 		if (copy_from_sockptr(&val, optval, sizeof(int))) {
3024 			rc = -EFAULT;
3025 			break;
3026 		}
3027 
3028 		smc->limit_smc_hs = !!val;
3029 		rc = 0;
3030 		break;
3031 	default:
3032 		rc = -EOPNOTSUPP;
3033 		break;
3034 	}
3035 	release_sock(sk);
3036 
3037 	return rc;
3038 }
3039 
3040 static int smc_setsockopt(struct socket *sock, int level, int optname,
3041 			  sockptr_t optval, unsigned int optlen)
3042 {
3043 	struct sock *sk = sock->sk;
3044 	struct smc_sock *smc;
3045 	int val, rc;
3046 
3047 	if (level == SOL_TCP && optname == TCP_ULP)
3048 		return -EOPNOTSUPP;
3049 	else if (level == SOL_SMC)
3050 		return __smc_setsockopt(sock, level, optname, optval, optlen);
3051 
3052 	smc = smc_sk(sk);
3053 
3054 	/* generic setsockopts reaching us here always apply to the
3055 	 * CLC socket
3056 	 */
3057 	mutex_lock(&smc->clcsock_release_lock);
3058 	if (!smc->clcsock) {
3059 		mutex_unlock(&smc->clcsock_release_lock);
3060 		return -EBADF;
3061 	}
3062 	if (unlikely(!smc->clcsock->ops->setsockopt))
3063 		rc = -EOPNOTSUPP;
3064 	else
3065 		rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
3066 						   optval, optlen);
3067 	if (smc->clcsock->sk->sk_err) {
3068 		sk->sk_err = smc->clcsock->sk->sk_err;
3069 		sk_error_report(sk);
3070 	}
3071 	mutex_unlock(&smc->clcsock_release_lock);
3072 
3073 	if (optlen < sizeof(int))
3074 		return -EINVAL;
3075 	if (copy_from_sockptr(&val, optval, sizeof(int)))
3076 		return -EFAULT;
3077 
3078 	lock_sock(sk);
3079 	if (rc || smc->use_fallback)
3080 		goto out;
3081 	switch (optname) {
3082 	case TCP_FASTOPEN:
3083 	case TCP_FASTOPEN_CONNECT:
3084 	case TCP_FASTOPEN_KEY:
3085 	case TCP_FASTOPEN_NO_COOKIE:
3086 		/* option not supported by SMC */
3087 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
3088 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
3089 		} else {
3090 			rc = -EINVAL;
3091 		}
3092 		break;
3093 	case TCP_NODELAY:
3094 		if (sk->sk_state != SMC_INIT &&
3095 		    sk->sk_state != SMC_LISTEN &&
3096 		    sk->sk_state != SMC_CLOSED) {
3097 			if (val) {
3098 				SMC_STAT_INC(smc, ndly_cnt);
3099 				smc_tx_pending(&smc->conn);
3100 				cancel_delayed_work(&smc->conn.tx_work);
3101 			}
3102 		}
3103 		break;
3104 	case TCP_CORK:
3105 		if (sk->sk_state != SMC_INIT &&
3106 		    sk->sk_state != SMC_LISTEN &&
3107 		    sk->sk_state != SMC_CLOSED) {
3108 			if (!val) {
3109 				SMC_STAT_INC(smc, cork_cnt);
3110 				smc_tx_pending(&smc->conn);
3111 				cancel_delayed_work(&smc->conn.tx_work);
3112 			}
3113 		}
3114 		break;
3115 	case TCP_DEFER_ACCEPT:
3116 		smc->sockopt_defer_accept = val;
3117 		break;
3118 	default:
3119 		break;
3120 	}
3121 out:
3122 	release_sock(sk);
3123 
3124 	return rc;
3125 }
3126 
3127 static int smc_getsockopt(struct socket *sock, int level, int optname,
3128 			  char __user *optval, int __user *optlen)
3129 {
3130 	struct smc_sock *smc;
3131 	int rc;
3132 
3133 	if (level == SOL_SMC)
3134 		return __smc_getsockopt(sock, level, optname, optval, optlen);
3135 
3136 	smc = smc_sk(sock->sk);
3137 	mutex_lock(&smc->clcsock_release_lock);
3138 	if (!smc->clcsock) {
3139 		mutex_unlock(&smc->clcsock_release_lock);
3140 		return -EBADF;
3141 	}
3142 	/* socket options apply to the CLC socket */
3143 	if (unlikely(!smc->clcsock->ops->getsockopt)) {
3144 		mutex_unlock(&smc->clcsock_release_lock);
3145 		return -EOPNOTSUPP;
3146 	}
3147 	rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3148 					   optval, optlen);
3149 	mutex_unlock(&smc->clcsock_release_lock);
3150 	return rc;
3151 }
3152 
3153 static int smc_ioctl(struct socket *sock, unsigned int cmd,
3154 		     unsigned long arg)
3155 {
3156 	union smc_host_cursor cons, urg;
3157 	struct smc_connection *conn;
3158 	struct smc_sock *smc;
3159 	int answ;
3160 
3161 	smc = smc_sk(sock->sk);
3162 	conn = &smc->conn;
3163 	lock_sock(&smc->sk);
3164 	if (smc->use_fallback) {
3165 		if (!smc->clcsock) {
3166 			release_sock(&smc->sk);
3167 			return -EBADF;
3168 		}
3169 		answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3170 		release_sock(&smc->sk);
3171 		return answ;
3172 	}
3173 	switch (cmd) {
3174 	case SIOCINQ: /* same as FIONREAD */
3175 		if (smc->sk.sk_state == SMC_LISTEN) {
3176 			release_sock(&smc->sk);
3177 			return -EINVAL;
3178 		}
3179 		if (smc->sk.sk_state == SMC_INIT ||
3180 		    smc->sk.sk_state == SMC_CLOSED)
3181 			answ = 0;
3182 		else
3183 			answ = atomic_read(&smc->conn.bytes_to_rcv);
3184 		break;
3185 	case SIOCOUTQ:
3186 		/* output queue size (not send + not acked) */
3187 		if (smc->sk.sk_state == SMC_LISTEN) {
3188 			release_sock(&smc->sk);
3189 			return -EINVAL;
3190 		}
3191 		if (smc->sk.sk_state == SMC_INIT ||
3192 		    smc->sk.sk_state == SMC_CLOSED)
3193 			answ = 0;
3194 		else
3195 			answ = smc->conn.sndbuf_desc->len -
3196 					atomic_read(&smc->conn.sndbuf_space);
3197 		break;
3198 	case SIOCOUTQNSD:
3199 		/* output queue size (not send only) */
3200 		if (smc->sk.sk_state == SMC_LISTEN) {
3201 			release_sock(&smc->sk);
3202 			return -EINVAL;
3203 		}
3204 		if (smc->sk.sk_state == SMC_INIT ||
3205 		    smc->sk.sk_state == SMC_CLOSED)
3206 			answ = 0;
3207 		else
3208 			answ = smc_tx_prepared_sends(&smc->conn);
3209 		break;
3210 	case SIOCATMARK:
3211 		if (smc->sk.sk_state == SMC_LISTEN) {
3212 			release_sock(&smc->sk);
3213 			return -EINVAL;
3214 		}
3215 		if (smc->sk.sk_state == SMC_INIT ||
3216 		    smc->sk.sk_state == SMC_CLOSED) {
3217 			answ = 0;
3218 		} else {
3219 			smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3220 			smc_curs_copy(&urg, &conn->urg_curs, conn);
3221 			answ = smc_curs_diff(conn->rmb_desc->len,
3222 					     &cons, &urg) == 1;
3223 		}
3224 		break;
3225 	default:
3226 		release_sock(&smc->sk);
3227 		return -ENOIOCTLCMD;
3228 	}
3229 	release_sock(&smc->sk);
3230 
3231 	return put_user(answ, (int __user *)arg);
3232 }
3233 
3234 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3235  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3236  * updates till whenever a respective page has been fully processed.
3237  * Note that subsequent recv() calls have to wait till all splice() processing
3238  * completed.
3239  */
3240 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3241 			       struct pipe_inode_info *pipe, size_t len,
3242 			       unsigned int flags)
3243 {
3244 	struct sock *sk = sock->sk;
3245 	struct smc_sock *smc;
3246 	int rc = -ENOTCONN;
3247 
3248 	smc = smc_sk(sk);
3249 	lock_sock(sk);
3250 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3251 		/* socket was connected before, no more data to read */
3252 		rc = 0;
3253 		goto out;
3254 	}
3255 	if (sk->sk_state == SMC_INIT ||
3256 	    sk->sk_state == SMC_LISTEN ||
3257 	    sk->sk_state == SMC_CLOSED)
3258 		goto out;
3259 
3260 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3261 		rc = 0;
3262 		goto out;
3263 	}
3264 
3265 	if (smc->use_fallback) {
3266 		rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3267 						    pipe, len, flags);
3268 	} else {
3269 		if (*ppos) {
3270 			rc = -ESPIPE;
3271 			goto out;
3272 		}
3273 		if (flags & SPLICE_F_NONBLOCK)
3274 			flags = MSG_DONTWAIT;
3275 		else
3276 			flags = 0;
3277 		SMC_STAT_INC(smc, splice_cnt);
3278 		rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3279 	}
3280 out:
3281 	release_sock(sk);
3282 
3283 	return rc;
3284 }
3285 
3286 /* must look like tcp */
3287 static const struct proto_ops smc_sock_ops = {
3288 	.family		= PF_SMC,
3289 	.owner		= THIS_MODULE,
3290 	.release	= smc_release,
3291 	.bind		= smc_bind,
3292 	.connect	= smc_connect,
3293 	.socketpair	= sock_no_socketpair,
3294 	.accept		= smc_accept,
3295 	.getname	= smc_getname,
3296 	.poll		= smc_poll,
3297 	.ioctl		= smc_ioctl,
3298 	.listen		= smc_listen,
3299 	.shutdown	= smc_shutdown,
3300 	.setsockopt	= smc_setsockopt,
3301 	.getsockopt	= smc_getsockopt,
3302 	.sendmsg	= smc_sendmsg,
3303 	.recvmsg	= smc_recvmsg,
3304 	.mmap		= sock_no_mmap,
3305 	.splice_read	= smc_splice_read,
3306 };
3307 
3308 static int __smc_create(struct net *net, struct socket *sock, int protocol,
3309 			int kern, struct socket *clcsock)
3310 {
3311 	int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3312 	struct smc_sock *smc;
3313 	struct sock *sk;
3314 	int rc;
3315 
3316 	rc = -ESOCKTNOSUPPORT;
3317 	if (sock->type != SOCK_STREAM)
3318 		goto out;
3319 
3320 	rc = -EPROTONOSUPPORT;
3321 	if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3322 		goto out;
3323 
3324 	rc = -ENOBUFS;
3325 	sock->ops = &smc_sock_ops;
3326 	sock->state = SS_UNCONNECTED;
3327 	sk = smc_sock_alloc(net, sock, protocol);
3328 	if (!sk)
3329 		goto out;
3330 
3331 	/* create internal TCP socket for CLC handshake and fallback */
3332 	smc = smc_sk(sk);
3333 	smc->use_fallback = false; /* assume rdma capability first */
3334 	smc->fallback_rsn = 0;
3335 
3336 	/* default behavior from limit_smc_hs in every net namespace */
3337 	smc->limit_smc_hs = net->smc.limit_smc_hs;
3338 
3339 	rc = 0;
3340 	if (!clcsock) {
3341 		rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3342 				      &smc->clcsock);
3343 		if (rc) {
3344 			sk_common_release(sk);
3345 			goto out;
3346 		}
3347 
3348 		/* smc_clcsock_release() does not wait smc->clcsock->sk's
3349 		 * destruction;  its sk_state might not be TCP_CLOSE after
3350 		 * smc->sk is close()d, and TCP timers can be fired later,
3351 		 * which need net ref.
3352 		 */
3353 		sk = smc->clcsock->sk;
3354 		__netns_tracker_free(net, &sk->ns_tracker, false);
3355 		sk->sk_net_refcnt = 1;
3356 		get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
3357 		sock_inuse_add(net, 1);
3358 	} else {
3359 		smc->clcsock = clcsock;
3360 	}
3361 
3362 out:
3363 	return rc;
3364 }
3365 
3366 static int smc_create(struct net *net, struct socket *sock, int protocol,
3367 		      int kern)
3368 {
3369 	return __smc_create(net, sock, protocol, kern, NULL);
3370 }
3371 
3372 static const struct net_proto_family smc_sock_family_ops = {
3373 	.family	= PF_SMC,
3374 	.owner	= THIS_MODULE,
3375 	.create	= smc_create,
3376 };
3377 
3378 static int smc_ulp_init(struct sock *sk)
3379 {
3380 	struct socket *tcp = sk->sk_socket;
3381 	struct net *net = sock_net(sk);
3382 	struct socket *smcsock;
3383 	int protocol, ret;
3384 
3385 	/* only TCP can be replaced */
3386 	if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3387 	    (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3388 		return -ESOCKTNOSUPPORT;
3389 	/* don't handle wq now */
3390 	if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3391 		return -ENOTCONN;
3392 
3393 	if (sk->sk_family == AF_INET)
3394 		protocol = SMCPROTO_SMC;
3395 	else
3396 		protocol = SMCPROTO_SMC6;
3397 
3398 	smcsock = sock_alloc();
3399 	if (!smcsock)
3400 		return -ENFILE;
3401 
3402 	smcsock->type = SOCK_STREAM;
3403 	__module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3404 	ret = __smc_create(net, smcsock, protocol, 1, tcp);
3405 	if (ret) {
3406 		sock_release(smcsock); /* module_put() which ops won't be NULL */
3407 		return ret;
3408 	}
3409 
3410 	/* replace tcp socket to smc */
3411 	smcsock->file = tcp->file;
3412 	smcsock->file->private_data = smcsock;
3413 	smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3414 	smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3415 	tcp->file = NULL;
3416 
3417 	return ret;
3418 }
3419 
3420 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3421 			  const gfp_t priority)
3422 {
3423 	struct inet_connection_sock *icsk = inet_csk(newsk);
3424 
3425 	/* don't inherit ulp ops to child when listen */
3426 	icsk->icsk_ulp_ops = NULL;
3427 }
3428 
3429 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3430 	.name		= "smc",
3431 	.owner		= THIS_MODULE,
3432 	.init		= smc_ulp_init,
3433 	.clone		= smc_ulp_clone,
3434 };
3435 
3436 unsigned int smc_net_id;
3437 
3438 static __net_init int smc_net_init(struct net *net)
3439 {
3440 	int rc;
3441 
3442 	rc = smc_sysctl_net_init(net);
3443 	if (rc)
3444 		return rc;
3445 	return smc_pnet_net_init(net);
3446 }
3447 
3448 static void __net_exit smc_net_exit(struct net *net)
3449 {
3450 	smc_sysctl_net_exit(net);
3451 	smc_pnet_net_exit(net);
3452 }
3453 
3454 static __net_init int smc_net_stat_init(struct net *net)
3455 {
3456 	return smc_stats_init(net);
3457 }
3458 
3459 static void __net_exit smc_net_stat_exit(struct net *net)
3460 {
3461 	smc_stats_exit(net);
3462 }
3463 
3464 static struct pernet_operations smc_net_ops = {
3465 	.init = smc_net_init,
3466 	.exit = smc_net_exit,
3467 	.id   = &smc_net_id,
3468 	.size = sizeof(struct smc_net),
3469 };
3470 
3471 static struct pernet_operations smc_net_stat_ops = {
3472 	.init = smc_net_stat_init,
3473 	.exit = smc_net_stat_exit,
3474 };
3475 
3476 static int __init smc_init(void)
3477 {
3478 	int rc;
3479 
3480 	rc = register_pernet_subsys(&smc_net_ops);
3481 	if (rc)
3482 		return rc;
3483 
3484 	rc = register_pernet_subsys(&smc_net_stat_ops);
3485 	if (rc)
3486 		goto out_pernet_subsys;
3487 
3488 	rc = smc_ism_init();
3489 	if (rc)
3490 		goto out_pernet_subsys_stat;
3491 	smc_clc_init();
3492 
3493 	rc = smc_nl_init();
3494 	if (rc)
3495 		goto out_ism;
3496 
3497 	rc = smc_pnet_init();
3498 	if (rc)
3499 		goto out_nl;
3500 
3501 	rc = -ENOMEM;
3502 
3503 	smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3504 	if (!smc_tcp_ls_wq)
3505 		goto out_pnet;
3506 
3507 	smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3508 	if (!smc_hs_wq)
3509 		goto out_alloc_tcp_ls_wq;
3510 
3511 	smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3512 	if (!smc_close_wq)
3513 		goto out_alloc_hs_wq;
3514 
3515 	rc = smc_core_init();
3516 	if (rc) {
3517 		pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3518 		goto out_alloc_wqs;
3519 	}
3520 
3521 	rc = smc_llc_init();
3522 	if (rc) {
3523 		pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3524 		goto out_core;
3525 	}
3526 
3527 	rc = smc_cdc_init();
3528 	if (rc) {
3529 		pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3530 		goto out_core;
3531 	}
3532 
3533 	rc = proto_register(&smc_proto, 1);
3534 	if (rc) {
3535 		pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3536 		goto out_core;
3537 	}
3538 
3539 	rc = proto_register(&smc_proto6, 1);
3540 	if (rc) {
3541 		pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3542 		goto out_proto;
3543 	}
3544 
3545 	rc = sock_register(&smc_sock_family_ops);
3546 	if (rc) {
3547 		pr_err("%s: sock_register fails with %d\n", __func__, rc);
3548 		goto out_proto6;
3549 	}
3550 	INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3551 	INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3552 
3553 	rc = smc_ib_register_client();
3554 	if (rc) {
3555 		pr_err("%s: ib_register fails with %d\n", __func__, rc);
3556 		goto out_sock;
3557 	}
3558 
3559 	rc = tcp_register_ulp(&smc_ulp_ops);
3560 	if (rc) {
3561 		pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3562 		goto out_ib;
3563 	}
3564 
3565 	static_branch_enable(&tcp_have_smc);
3566 	return 0;
3567 
3568 out_ib:
3569 	smc_ib_unregister_client();
3570 out_sock:
3571 	sock_unregister(PF_SMC);
3572 out_proto6:
3573 	proto_unregister(&smc_proto6);
3574 out_proto:
3575 	proto_unregister(&smc_proto);
3576 out_core:
3577 	smc_core_exit();
3578 out_alloc_wqs:
3579 	destroy_workqueue(smc_close_wq);
3580 out_alloc_hs_wq:
3581 	destroy_workqueue(smc_hs_wq);
3582 out_alloc_tcp_ls_wq:
3583 	destroy_workqueue(smc_tcp_ls_wq);
3584 out_pnet:
3585 	smc_pnet_exit();
3586 out_nl:
3587 	smc_nl_exit();
3588 out_ism:
3589 	smc_clc_exit();
3590 	smc_ism_exit();
3591 out_pernet_subsys_stat:
3592 	unregister_pernet_subsys(&smc_net_stat_ops);
3593 out_pernet_subsys:
3594 	unregister_pernet_subsys(&smc_net_ops);
3595 
3596 	return rc;
3597 }
3598 
3599 static void __exit smc_exit(void)
3600 {
3601 	static_branch_disable(&tcp_have_smc);
3602 	tcp_unregister_ulp(&smc_ulp_ops);
3603 	sock_unregister(PF_SMC);
3604 	smc_core_exit();
3605 	smc_ib_unregister_client();
3606 	smc_ism_exit();
3607 	destroy_workqueue(smc_close_wq);
3608 	destroy_workqueue(smc_tcp_ls_wq);
3609 	destroy_workqueue(smc_hs_wq);
3610 	proto_unregister(&smc_proto6);
3611 	proto_unregister(&smc_proto);
3612 	smc_pnet_exit();
3613 	smc_nl_exit();
3614 	smc_clc_exit();
3615 	unregister_pernet_subsys(&smc_net_stat_ops);
3616 	unregister_pernet_subsys(&smc_net_ops);
3617 	rcu_barrier();
3618 }
3619 
3620 module_init(smc_init);
3621 module_exit(smc_exit);
3622 
3623 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3624 MODULE_DESCRIPTION("smc socket address family");
3625 MODULE_LICENSE("GPL");
3626 MODULE_ALIAS_NETPROTO(PF_SMC);
3627 MODULE_ALIAS_TCP_ULP("smc");
3628 MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);
3629