xref: /linux/net/smc/af_smc.c (revision da51bbcdbace8f43adf6066934c3926b656376e5)
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 		smc->sk.sk_socket->wq.fasync_list = NULL;
928 
929 		/* There might be some wait entries remaining
930 		 * in smc sk->sk_wq and they should be woken up
931 		 * as clcsock's wait queue is woken up.
932 		 */
933 		smc_fback_replace_callbacks(smc);
934 	}
935 out:
936 	mutex_unlock(&smc->clcsock_release_lock);
937 	return rc;
938 }
939 
940 /* fall back during connect */
941 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
942 {
943 	struct net *net = sock_net(&smc->sk);
944 	int rc = 0;
945 
946 	rc = smc_switch_to_fallback(smc, reason_code);
947 	if (rc) { /* fallback fails */
948 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
949 		if (smc->sk.sk_state == SMC_INIT)
950 			sock_put(&smc->sk); /* passive closing */
951 		return rc;
952 	}
953 	smc_copy_sock_settings_to_clc(smc);
954 	smc->connect_nonblock = 0;
955 	if (smc->sk.sk_state == SMC_INIT)
956 		smc->sk.sk_state = SMC_ACTIVE;
957 	return 0;
958 }
959 
960 /* decline and fall back during connect */
961 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
962 					u8 version)
963 {
964 	struct net *net = sock_net(&smc->sk);
965 	int rc;
966 
967 	if (reason_code < 0) { /* error, fallback is not possible */
968 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
969 		if (smc->sk.sk_state == SMC_INIT)
970 			sock_put(&smc->sk); /* passive closing */
971 		return reason_code;
972 	}
973 	if (reason_code != SMC_CLC_DECL_PEERDECL) {
974 		rc = smc_clc_send_decline(smc, reason_code, version);
975 		if (rc < 0) {
976 			this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
977 			if (smc->sk.sk_state == SMC_INIT)
978 				sock_put(&smc->sk); /* passive closing */
979 			return rc;
980 		}
981 	}
982 	return smc_connect_fallback(smc, reason_code);
983 }
984 
985 static void smc_conn_abort(struct smc_sock *smc, int local_first)
986 {
987 	struct smc_connection *conn = &smc->conn;
988 	struct smc_link_group *lgr = conn->lgr;
989 	bool lgr_valid = false;
990 
991 	if (smc_conn_lgr_valid(conn))
992 		lgr_valid = true;
993 
994 	smc_conn_free(conn);
995 	if (local_first && lgr_valid)
996 		smc_lgr_cleanup_early(lgr);
997 }
998 
999 /* check if there is a rdma device available for this connection. */
1000 /* called for connect and listen */
1001 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
1002 {
1003 	/* PNET table look up: search active ib_device and port
1004 	 * within same PNETID that also contains the ethernet device
1005 	 * used for the internal TCP socket
1006 	 */
1007 	smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
1008 	if (!ini->check_smcrv2 && !ini->ib_dev)
1009 		return SMC_CLC_DECL_NOSMCRDEV;
1010 	if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
1011 		return SMC_CLC_DECL_NOSMCRDEV;
1012 	return 0;
1013 }
1014 
1015 /* check if there is an ISM device available for this connection. */
1016 /* called for connect and listen */
1017 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
1018 {
1019 	/* Find ISM device with same PNETID as connecting interface  */
1020 	smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
1021 	if (!ini->ism_dev[0])
1022 		return SMC_CLC_DECL_NOSMCDDEV;
1023 	else
1024 		ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
1025 	return 0;
1026 }
1027 
1028 /* is chid unique for the ism devices that are already determined? */
1029 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
1030 					   int cnt)
1031 {
1032 	int i = (!ini->ism_dev[0]) ? 1 : 0;
1033 
1034 	for (; i < cnt; i++)
1035 		if (ini->ism_chid[i] == chid)
1036 			return false;
1037 	return true;
1038 }
1039 
1040 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
1041  * PNETID matching net_device)
1042  */
1043 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
1044 				       struct smc_init_info *ini)
1045 {
1046 	int rc = SMC_CLC_DECL_NOSMCDDEV;
1047 	struct smcd_dev *smcd;
1048 	int i = 1, entry = 1;
1049 	bool is_emulated;
1050 	u16 chid;
1051 
1052 	if (smcd_indicated(ini->smc_type_v1))
1053 		rc = 0;		/* already initialized for V1 */
1054 	mutex_lock(&smcd_dev_list.mutex);
1055 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1056 		if (smcd->going_away || smcd == ini->ism_dev[0])
1057 			continue;
1058 		chid = smc_ism_get_chid(smcd);
1059 		if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
1060 			continue;
1061 		is_emulated = __smc_ism_is_emulated(chid);
1062 		if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
1063 		    smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
1064 			if (is_emulated && entry == SMCD_CLC_MAX_V2_GID_ENTRIES)
1065 				/* It's the last GID-CHID entry left in CLC
1066 				 * Proposal SMC-Dv2 extension, but an Emulated-
1067 				 * ISM device will take two entries. So give
1068 				 * up it and try the next potential ISM device.
1069 				 */
1070 				continue;
1071 			ini->ism_dev[i] = smcd;
1072 			ini->ism_chid[i] = chid;
1073 			ini->is_smcd = true;
1074 			rc = 0;
1075 			i++;
1076 			entry = is_emulated ? entry + 2 : entry + 1;
1077 			if (entry > SMCD_CLC_MAX_V2_GID_ENTRIES)
1078 				break;
1079 		}
1080 	}
1081 	mutex_unlock(&smcd_dev_list.mutex);
1082 	ini->ism_offered_cnt = i - 1;
1083 	if (!ini->ism_dev[0] && !ini->ism_dev[1])
1084 		ini->smcd_version = 0;
1085 
1086 	return rc;
1087 }
1088 
1089 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
1090 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
1091 				      struct smc_init_info *ini)
1092 {
1093 	if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
1094 		return SMC_CLC_DECL_ISMVLANERR;
1095 	return 0;
1096 }
1097 
1098 static int smc_find_proposal_devices(struct smc_sock *smc,
1099 				     struct smc_init_info *ini)
1100 {
1101 	int rc = 0;
1102 
1103 	/* check if there is an ism device available */
1104 	if (!(ini->smcd_version & SMC_V1) ||
1105 	    smc_find_ism_device(smc, ini) ||
1106 	    smc_connect_ism_vlan_setup(smc, ini))
1107 		ini->smcd_version &= ~SMC_V1;
1108 	/* else ISM V1 is supported for this connection */
1109 
1110 	/* check if there is an rdma device available */
1111 	if (!(ini->smcr_version & SMC_V1) ||
1112 	    smc_find_rdma_device(smc, ini))
1113 		ini->smcr_version &= ~SMC_V1;
1114 	/* else RDMA is supported for this connection */
1115 
1116 	ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
1117 					      ini->smcr_version & SMC_V1);
1118 
1119 	/* check if there is an ism v2 device available */
1120 	if (!(ini->smcd_version & SMC_V2) ||
1121 	    !smc_ism_is_v2_capable() ||
1122 	    smc_find_ism_v2_device_clnt(smc, ini))
1123 		ini->smcd_version &= ~SMC_V2;
1124 
1125 	/* check if there is an rdma v2 device available */
1126 	ini->check_smcrv2 = true;
1127 	ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
1128 	if (!(ini->smcr_version & SMC_V2) ||
1129 	    smc->clcsock->sk->sk_family != AF_INET ||
1130 	    !smc_clc_ueid_count() ||
1131 	    smc_find_rdma_device(smc, ini))
1132 		ini->smcr_version &= ~SMC_V2;
1133 	ini->check_smcrv2 = false;
1134 
1135 	ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
1136 					      ini->smcr_version & SMC_V2);
1137 
1138 	/* if neither ISM nor RDMA are supported, fallback */
1139 	if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
1140 		rc = SMC_CLC_DECL_NOSMCDEV;
1141 
1142 	return rc;
1143 }
1144 
1145 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
1146  * used, the VLAN ID will be registered again during the connection setup.
1147  */
1148 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
1149 					struct smc_init_info *ini)
1150 {
1151 	if (!smcd_indicated(ini->smc_type_v1))
1152 		return 0;
1153 	if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
1154 		return SMC_CLC_DECL_CNFERR;
1155 	return 0;
1156 }
1157 
1158 #define SMC_CLC_MAX_ACCEPT_LEN \
1159 	(sizeof(struct smc_clc_msg_accept_confirm) + \
1160 	 sizeof(struct smc_clc_first_contact_ext_v2x) + \
1161 	 sizeof(struct smc_clc_msg_trail))
1162 
1163 /* CLC handshake during connect */
1164 static int smc_connect_clc(struct smc_sock *smc,
1165 			   struct smc_clc_msg_accept_confirm *aclc,
1166 			   struct smc_init_info *ini)
1167 {
1168 	int rc = 0;
1169 
1170 	/* do inband token exchange */
1171 	rc = smc_clc_send_proposal(smc, ini);
1172 	if (rc)
1173 		return rc;
1174 	/* receive SMC Accept CLC message */
1175 	return smc_clc_wait_msg(smc, aclc, SMC_CLC_MAX_ACCEPT_LEN,
1176 				SMC_CLC_ACCEPT, CLC_WAIT_TIME);
1177 }
1178 
1179 void smc_fill_gid_list(struct smc_link_group *lgr,
1180 		       struct smc_gidlist *gidlist,
1181 		       struct smc_ib_device *known_dev, u8 *known_gid)
1182 {
1183 	struct smc_init_info *alt_ini = NULL;
1184 
1185 	memset(gidlist, 0, sizeof(*gidlist));
1186 	memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
1187 
1188 	alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
1189 	if (!alt_ini)
1190 		goto out;
1191 
1192 	alt_ini->vlan_id = lgr->vlan_id;
1193 	alt_ini->check_smcrv2 = true;
1194 	alt_ini->smcrv2.saddr = lgr->saddr;
1195 	smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
1196 
1197 	if (!alt_ini->smcrv2.ib_dev_v2)
1198 		goto out;
1199 
1200 	memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
1201 	       SMC_GID_SIZE);
1202 
1203 out:
1204 	kfree(alt_ini);
1205 }
1206 
1207 static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
1208 				       struct smc_clc_msg_accept_confirm *aclc,
1209 				       struct smc_init_info *ini)
1210 {
1211 	struct smc_clc_first_contact_ext *fce =
1212 		smc_get_clc_first_contact_ext(aclc, false);
1213 	struct net *net = sock_net(&smc->sk);
1214 	int rc;
1215 
1216 	if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1217 		return 0;
1218 
1219 	if (fce->v2_direct) {
1220 		memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1221 		ini->smcrv2.uses_gateway = false;
1222 	} else {
1223 		if (smc_ib_find_route(net, smc->clcsock->sk->sk_rcv_saddr,
1224 				      smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1225 				      ini->smcrv2.nexthop_mac,
1226 				      &ini->smcrv2.uses_gateway))
1227 			return SMC_CLC_DECL_NOROUTE;
1228 		if (!ini->smcrv2.uses_gateway) {
1229 			/* mismatch: peer claims indirect, but its direct */
1230 			return SMC_CLC_DECL_NOINDIRECT;
1231 		}
1232 	}
1233 
1234 	ini->release_nr = fce->release;
1235 	rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1236 	if (rc)
1237 		return rc;
1238 
1239 	return 0;
1240 }
1241 
1242 /* setup for RDMA connection of client */
1243 static int smc_connect_rdma(struct smc_sock *smc,
1244 			    struct smc_clc_msg_accept_confirm *aclc,
1245 			    struct smc_init_info *ini)
1246 {
1247 	int i, reason_code = 0;
1248 	struct smc_link *link;
1249 	u8 *eid = NULL;
1250 
1251 	ini->is_smcd = false;
1252 	ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1253 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1254 	memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1255 	memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1256 	memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1257 	ini->max_conns = SMC_CONN_PER_LGR_MAX;
1258 	ini->max_links = SMC_LINKS_ADD_LNK_MAX;
1259 
1260 	reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1261 	if (reason_code)
1262 		return reason_code;
1263 
1264 	mutex_lock(&smc_client_lgr_pending);
1265 	reason_code = smc_conn_create(smc, ini);
1266 	if (reason_code) {
1267 		mutex_unlock(&smc_client_lgr_pending);
1268 		return reason_code;
1269 	}
1270 
1271 	smc_conn_save_peer_info(smc, aclc);
1272 
1273 	if (ini->first_contact_local) {
1274 		link = smc->conn.lnk;
1275 	} else {
1276 		/* set link that was assigned by server */
1277 		link = NULL;
1278 		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1279 			struct smc_link *l = &smc->conn.lgr->lnk[i];
1280 
1281 			if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1282 			    !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1283 				    SMC_GID_SIZE) &&
1284 			    (aclc->hdr.version > SMC_V1 ||
1285 			     !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1286 				     sizeof(l->peer_mac)))) {
1287 				link = l;
1288 				break;
1289 			}
1290 		}
1291 		if (!link) {
1292 			reason_code = SMC_CLC_DECL_NOSRVLINK;
1293 			goto connect_abort;
1294 		}
1295 		smc_switch_link_and_count(&smc->conn, link);
1296 	}
1297 
1298 	/* create send buffer and rmb */
1299 	if (smc_buf_create(smc, false)) {
1300 		reason_code = SMC_CLC_DECL_MEM;
1301 		goto connect_abort;
1302 	}
1303 
1304 	if (ini->first_contact_local)
1305 		smc_link_save_peer_info(link, aclc, ini);
1306 
1307 	if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1308 		reason_code = SMC_CLC_DECL_ERR_RTOK;
1309 		goto connect_abort;
1310 	}
1311 
1312 	smc_close_init(smc);
1313 	smc_rx_init(smc);
1314 
1315 	if (ini->first_contact_local) {
1316 		if (smc_ib_ready_link(link)) {
1317 			reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1318 			goto connect_abort;
1319 		}
1320 	} else {
1321 		/* reg sendbufs if they were vzalloced */
1322 		if (smc->conn.sndbuf_desc->is_vm) {
1323 			if (smcr_lgr_reg_sndbufs(link, smc->conn.sndbuf_desc)) {
1324 				reason_code = SMC_CLC_DECL_ERR_REGBUF;
1325 				goto connect_abort;
1326 			}
1327 		}
1328 		if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1329 			reason_code = SMC_CLC_DECL_ERR_REGBUF;
1330 			goto connect_abort;
1331 		}
1332 	}
1333 
1334 	if (aclc->hdr.version > SMC_V1) {
1335 		eid = aclc->r1.eid;
1336 		if (ini->first_contact_local)
1337 			smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1338 					  link->smcibdev, link->gid);
1339 	}
1340 
1341 	reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1342 					   aclc->hdr.version, eid, ini);
1343 	if (reason_code)
1344 		goto connect_abort;
1345 
1346 	smc_tx_init(smc);
1347 
1348 	if (ini->first_contact_local) {
1349 		/* QP confirmation over RoCE fabric */
1350 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1351 		reason_code = smcr_clnt_conf_first_link(smc);
1352 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1353 		if (reason_code)
1354 			goto connect_abort;
1355 	}
1356 	mutex_unlock(&smc_client_lgr_pending);
1357 
1358 	smc_copy_sock_settings_to_clc(smc);
1359 	smc->connect_nonblock = 0;
1360 	if (smc->sk.sk_state == SMC_INIT)
1361 		smc->sk.sk_state = SMC_ACTIVE;
1362 
1363 	return 0;
1364 connect_abort:
1365 	smc_conn_abort(smc, ini->first_contact_local);
1366 	mutex_unlock(&smc_client_lgr_pending);
1367 	smc->connect_nonblock = 0;
1368 
1369 	return reason_code;
1370 }
1371 
1372 /* The server has chosen one of the proposed ISM devices for the communication.
1373  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1374  */
1375 static int
1376 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm *aclc,
1377 			       struct smc_init_info *ini)
1378 {
1379 	int i;
1380 
1381 	for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1382 		if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1383 			ini->ism_selected = i;
1384 			return 0;
1385 		}
1386 	}
1387 
1388 	return -EPROTO;
1389 }
1390 
1391 /* setup for ISM connection of client */
1392 static int smc_connect_ism(struct smc_sock *smc,
1393 			   struct smc_clc_msg_accept_confirm *aclc,
1394 			   struct smc_init_info *ini)
1395 {
1396 	u8 *eid = NULL;
1397 	int rc = 0;
1398 
1399 	ini->is_smcd = true;
1400 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1401 
1402 	if (aclc->hdr.version == SMC_V2) {
1403 		if (ini->first_contact_peer) {
1404 			struct smc_clc_first_contact_ext *fce =
1405 				smc_get_clc_first_contact_ext(aclc, true);
1406 
1407 			ini->release_nr = fce->release;
1408 			rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1409 			if (rc)
1410 				return rc;
1411 		}
1412 
1413 		rc = smc_v2_determine_accepted_chid(aclc, ini);
1414 		if (rc)
1415 			return rc;
1416 
1417 		if (__smc_ism_is_emulated(ini->ism_chid[ini->ism_selected]))
1418 			ini->ism_peer_gid[ini->ism_selected].gid_ext =
1419 						ntohll(aclc->d1.gid_ext);
1420 		/* for non-Emulated-ISM devices, peer gid_ext remains 0. */
1421 	}
1422 	ini->ism_peer_gid[ini->ism_selected].gid = ntohll(aclc->d0.gid);
1423 
1424 	/* there is only one lgr role for SMC-D; use server lock */
1425 	mutex_lock(&smc_server_lgr_pending);
1426 	rc = smc_conn_create(smc, ini);
1427 	if (rc) {
1428 		mutex_unlock(&smc_server_lgr_pending);
1429 		return rc;
1430 	}
1431 
1432 	/* Create send and receive buffers */
1433 	rc = smc_buf_create(smc, true);
1434 	if (rc) {
1435 		rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1436 		goto connect_abort;
1437 	}
1438 
1439 	smc_conn_save_peer_info(smc, aclc);
1440 	smc_close_init(smc);
1441 	smc_rx_init(smc);
1442 	smc_tx_init(smc);
1443 
1444 	if (aclc->hdr.version > SMC_V1)
1445 		eid = aclc->d1.eid;
1446 
1447 	rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1448 				  aclc->hdr.version, eid, ini);
1449 	if (rc)
1450 		goto connect_abort;
1451 	mutex_unlock(&smc_server_lgr_pending);
1452 
1453 	smc_copy_sock_settings_to_clc(smc);
1454 	smc->connect_nonblock = 0;
1455 	if (smc->sk.sk_state == SMC_INIT)
1456 		smc->sk.sk_state = SMC_ACTIVE;
1457 
1458 	return 0;
1459 connect_abort:
1460 	smc_conn_abort(smc, ini->first_contact_local);
1461 	mutex_unlock(&smc_server_lgr_pending);
1462 	smc->connect_nonblock = 0;
1463 
1464 	return rc;
1465 }
1466 
1467 /* check if received accept type and version matches a proposed one */
1468 static int smc_connect_check_aclc(struct smc_init_info *ini,
1469 				  struct smc_clc_msg_accept_confirm *aclc)
1470 {
1471 	if (aclc->hdr.typev1 != SMC_TYPE_R &&
1472 	    aclc->hdr.typev1 != SMC_TYPE_D)
1473 		return SMC_CLC_DECL_MODEUNSUPP;
1474 
1475 	if (aclc->hdr.version >= SMC_V2) {
1476 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1477 		     !smcr_indicated(ini->smc_type_v2)) ||
1478 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1479 		     !smcd_indicated(ini->smc_type_v2)))
1480 			return SMC_CLC_DECL_MODEUNSUPP;
1481 	} else {
1482 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1483 		     !smcr_indicated(ini->smc_type_v1)) ||
1484 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1485 		     !smcd_indicated(ini->smc_type_v1)))
1486 			return SMC_CLC_DECL_MODEUNSUPP;
1487 	}
1488 
1489 	return 0;
1490 }
1491 
1492 /* perform steps before actually connecting */
1493 static int __smc_connect(struct smc_sock *smc)
1494 {
1495 	u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1496 	struct smc_clc_msg_accept_confirm *aclc;
1497 	struct smc_init_info *ini = NULL;
1498 	u8 *buf = NULL;
1499 	int rc = 0;
1500 
1501 	if (smc->use_fallback)
1502 		return smc_connect_fallback(smc, smc->fallback_rsn);
1503 
1504 	/* if peer has not signalled SMC-capability, fall back */
1505 	if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1506 		return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1507 
1508 	/* IPSec connections opt out of SMC optimizations */
1509 	if (using_ipsec(smc))
1510 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1511 						    version);
1512 
1513 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1514 	if (!ini)
1515 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1516 						    version);
1517 
1518 	ini->smcd_version = SMC_V1 | SMC_V2;
1519 	ini->smcr_version = SMC_V1 | SMC_V2;
1520 	ini->smc_type_v1 = SMC_TYPE_B;
1521 	ini->smc_type_v2 = SMC_TYPE_B;
1522 
1523 	/* get vlan id from IP device */
1524 	if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1525 		ini->smcd_version &= ~SMC_V1;
1526 		ini->smcr_version = 0;
1527 		ini->smc_type_v1 = SMC_TYPE_N;
1528 		if (!ini->smcd_version) {
1529 			rc = SMC_CLC_DECL_GETVLANERR;
1530 			goto fallback;
1531 		}
1532 	}
1533 
1534 	rc = smc_find_proposal_devices(smc, ini);
1535 	if (rc)
1536 		goto fallback;
1537 
1538 	buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1539 	if (!buf) {
1540 		rc = SMC_CLC_DECL_MEM;
1541 		goto fallback;
1542 	}
1543 	aclc = (struct smc_clc_msg_accept_confirm *)buf;
1544 
1545 	/* perform CLC handshake */
1546 	rc = smc_connect_clc(smc, aclc, ini);
1547 	if (rc) {
1548 		/* -EAGAIN on timeout, see tcp_recvmsg() */
1549 		if (rc == -EAGAIN) {
1550 			rc = -ETIMEDOUT;
1551 			smc->sk.sk_err = ETIMEDOUT;
1552 		}
1553 		goto vlan_cleanup;
1554 	}
1555 
1556 	/* check if smc modes and versions of CLC proposal and accept match */
1557 	rc = smc_connect_check_aclc(ini, aclc);
1558 	version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1559 	if (rc)
1560 		goto vlan_cleanup;
1561 
1562 	/* depending on previous steps, connect using rdma or ism */
1563 	if (aclc->hdr.typev1 == SMC_TYPE_R) {
1564 		ini->smcr_version = version;
1565 		rc = smc_connect_rdma(smc, aclc, ini);
1566 	} else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1567 		ini->smcd_version = version;
1568 		rc = smc_connect_ism(smc, aclc, ini);
1569 	}
1570 	if (rc)
1571 		goto vlan_cleanup;
1572 
1573 	SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1574 	smc_connect_ism_vlan_cleanup(smc, ini);
1575 	kfree(buf);
1576 	kfree(ini);
1577 	return 0;
1578 
1579 vlan_cleanup:
1580 	smc_connect_ism_vlan_cleanup(smc, ini);
1581 	kfree(buf);
1582 fallback:
1583 	kfree(ini);
1584 	return smc_connect_decline_fallback(smc, rc, version);
1585 }
1586 
1587 static void smc_connect_work(struct work_struct *work)
1588 {
1589 	struct smc_sock *smc = container_of(work, struct smc_sock,
1590 					    connect_work);
1591 	long timeo = smc->sk.sk_sndtimeo;
1592 	int rc = 0;
1593 
1594 	if (!timeo)
1595 		timeo = MAX_SCHEDULE_TIMEOUT;
1596 	lock_sock(smc->clcsock->sk);
1597 	if (smc->clcsock->sk->sk_err) {
1598 		smc->sk.sk_err = smc->clcsock->sk->sk_err;
1599 	} else if ((1 << smc->clcsock->sk->sk_state) &
1600 					(TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1601 		rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1602 		if ((rc == -EPIPE) &&
1603 		    ((1 << smc->clcsock->sk->sk_state) &
1604 					(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1605 			rc = 0;
1606 	}
1607 	release_sock(smc->clcsock->sk);
1608 	lock_sock(&smc->sk);
1609 	if (rc != 0 || smc->sk.sk_err) {
1610 		smc->sk.sk_state = SMC_CLOSED;
1611 		if (rc == -EPIPE || rc == -EAGAIN)
1612 			smc->sk.sk_err = EPIPE;
1613 		else if (rc == -ECONNREFUSED)
1614 			smc->sk.sk_err = ECONNREFUSED;
1615 		else if (signal_pending(current))
1616 			smc->sk.sk_err = -sock_intr_errno(timeo);
1617 		sock_put(&smc->sk); /* passive closing */
1618 		goto out;
1619 	}
1620 
1621 	rc = __smc_connect(smc);
1622 	if (rc < 0)
1623 		smc->sk.sk_err = -rc;
1624 
1625 out:
1626 	if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1627 		if (smc->sk.sk_err) {
1628 			smc->sk.sk_state_change(&smc->sk);
1629 		} else { /* allow polling before and after fallback decision */
1630 			smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1631 			smc->sk.sk_write_space(&smc->sk);
1632 		}
1633 	}
1634 	release_sock(&smc->sk);
1635 }
1636 
1637 static int smc_connect(struct socket *sock, struct sockaddr *addr,
1638 		       int alen, int flags)
1639 {
1640 	struct sock *sk = sock->sk;
1641 	struct smc_sock *smc;
1642 	int rc = -EINVAL;
1643 
1644 	smc = smc_sk(sk);
1645 
1646 	/* separate smc parameter checking to be safe */
1647 	if (alen < sizeof(addr->sa_family))
1648 		goto out_err;
1649 	if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1650 		goto out_err;
1651 
1652 	lock_sock(sk);
1653 	switch (sock->state) {
1654 	default:
1655 		rc = -EINVAL;
1656 		goto out;
1657 	case SS_CONNECTED:
1658 		rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1659 		goto out;
1660 	case SS_CONNECTING:
1661 		if (sk->sk_state == SMC_ACTIVE)
1662 			goto connected;
1663 		break;
1664 	case SS_UNCONNECTED:
1665 		sock->state = SS_CONNECTING;
1666 		break;
1667 	}
1668 
1669 	switch (sk->sk_state) {
1670 	default:
1671 		goto out;
1672 	case SMC_CLOSED:
1673 		rc = sock_error(sk) ? : -ECONNABORTED;
1674 		sock->state = SS_UNCONNECTED;
1675 		goto out;
1676 	case SMC_ACTIVE:
1677 		rc = -EISCONN;
1678 		goto out;
1679 	case SMC_INIT:
1680 		break;
1681 	}
1682 
1683 	smc_copy_sock_settings_to_clc(smc);
1684 	tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1685 	if (smc->connect_nonblock) {
1686 		rc = -EALREADY;
1687 		goto out;
1688 	}
1689 	rc = kernel_connect(smc->clcsock, addr, alen, flags);
1690 	if (rc && rc != -EINPROGRESS)
1691 		goto out;
1692 
1693 	if (smc->use_fallback) {
1694 		sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1695 		goto out;
1696 	}
1697 	sock_hold(&smc->sk); /* sock put in passive closing */
1698 	if (flags & O_NONBLOCK) {
1699 		if (queue_work(smc_hs_wq, &smc->connect_work))
1700 			smc->connect_nonblock = 1;
1701 		rc = -EINPROGRESS;
1702 		goto out;
1703 	} else {
1704 		rc = __smc_connect(smc);
1705 		if (rc < 0)
1706 			goto out;
1707 	}
1708 
1709 connected:
1710 	rc = 0;
1711 	sock->state = SS_CONNECTED;
1712 out:
1713 	release_sock(sk);
1714 out_err:
1715 	return rc;
1716 }
1717 
1718 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1719 {
1720 	struct socket *new_clcsock = NULL;
1721 	struct sock *lsk = &lsmc->sk;
1722 	struct sock *new_sk;
1723 	int rc = -EINVAL;
1724 
1725 	release_sock(lsk);
1726 	new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1727 	if (!new_sk) {
1728 		rc = -ENOMEM;
1729 		lsk->sk_err = ENOMEM;
1730 		*new_smc = NULL;
1731 		lock_sock(lsk);
1732 		goto out;
1733 	}
1734 	*new_smc = smc_sk(new_sk);
1735 
1736 	mutex_lock(&lsmc->clcsock_release_lock);
1737 	if (lsmc->clcsock)
1738 		rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1739 	mutex_unlock(&lsmc->clcsock_release_lock);
1740 	lock_sock(lsk);
1741 	if  (rc < 0 && rc != -EAGAIN)
1742 		lsk->sk_err = -rc;
1743 	if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1744 		new_sk->sk_prot->unhash(new_sk);
1745 		if (new_clcsock)
1746 			sock_release(new_clcsock);
1747 		new_sk->sk_state = SMC_CLOSED;
1748 		smc_sock_set_flag(new_sk, SOCK_DEAD);
1749 		sock_put(new_sk); /* final */
1750 		*new_smc = NULL;
1751 		goto out;
1752 	}
1753 
1754 	/* new clcsock has inherited the smc listen-specific sk_data_ready
1755 	 * function; switch it back to the original sk_data_ready function
1756 	 */
1757 	new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1758 
1759 	/* if new clcsock has also inherited the fallback-specific callback
1760 	 * functions, switch them back to the original ones.
1761 	 */
1762 	if (lsmc->use_fallback) {
1763 		if (lsmc->clcsk_state_change)
1764 			new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1765 		if (lsmc->clcsk_write_space)
1766 			new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1767 		if (lsmc->clcsk_error_report)
1768 			new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1769 	}
1770 
1771 	(*new_smc)->clcsock = new_clcsock;
1772 out:
1773 	return rc;
1774 }
1775 
1776 /* add a just created sock to the accept queue of the listen sock as
1777  * candidate for a following socket accept call from user space
1778  */
1779 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1780 {
1781 	struct smc_sock *par = smc_sk(parent);
1782 
1783 	sock_hold(sk); /* sock_put in smc_accept_unlink () */
1784 	spin_lock(&par->accept_q_lock);
1785 	list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1786 	spin_unlock(&par->accept_q_lock);
1787 	sk_acceptq_added(parent);
1788 }
1789 
1790 /* remove a socket from the accept queue of its parental listening socket */
1791 static void smc_accept_unlink(struct sock *sk)
1792 {
1793 	struct smc_sock *par = smc_sk(sk)->listen_smc;
1794 
1795 	spin_lock(&par->accept_q_lock);
1796 	list_del_init(&smc_sk(sk)->accept_q);
1797 	spin_unlock(&par->accept_q_lock);
1798 	sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1799 	sock_put(sk); /* sock_hold in smc_accept_enqueue */
1800 }
1801 
1802 /* remove a sock from the accept queue to bind it to a new socket created
1803  * for a socket accept call from user space
1804  */
1805 struct sock *smc_accept_dequeue(struct sock *parent,
1806 				struct socket *new_sock)
1807 {
1808 	struct smc_sock *isk, *n;
1809 	struct sock *new_sk;
1810 
1811 	list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1812 		new_sk = (struct sock *)isk;
1813 
1814 		smc_accept_unlink(new_sk);
1815 		if (new_sk->sk_state == SMC_CLOSED) {
1816 			new_sk->sk_prot->unhash(new_sk);
1817 			if (isk->clcsock) {
1818 				sock_release(isk->clcsock);
1819 				isk->clcsock = NULL;
1820 			}
1821 			sock_put(new_sk); /* final */
1822 			continue;
1823 		}
1824 		if (new_sock) {
1825 			sock_graft(new_sk, new_sock);
1826 			new_sock->state = SS_CONNECTED;
1827 			if (isk->use_fallback) {
1828 				smc_sk(new_sk)->clcsock->file = new_sock->file;
1829 				isk->clcsock->file->private_data = isk->clcsock;
1830 			}
1831 		}
1832 		return new_sk;
1833 	}
1834 	return NULL;
1835 }
1836 
1837 /* clean up for a created but never accepted sock */
1838 void smc_close_non_accepted(struct sock *sk)
1839 {
1840 	struct smc_sock *smc = smc_sk(sk);
1841 
1842 	sock_hold(sk); /* sock_put below */
1843 	lock_sock(sk);
1844 	if (!sk->sk_lingertime)
1845 		/* wait for peer closing */
1846 		WRITE_ONCE(sk->sk_lingertime, SMC_MAX_STREAM_WAIT_TIMEOUT);
1847 	__smc_release(smc);
1848 	release_sock(sk);
1849 	sock_put(sk); /* sock_hold above */
1850 	sock_put(sk); /* final sock_put */
1851 }
1852 
1853 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1854 {
1855 	struct smc_link *link = smc->conn.lnk;
1856 	struct smc_llc_qentry *qentry;
1857 	int rc;
1858 
1859 	/* reg the sndbuf if it was vzalloced*/
1860 	if (smc->conn.sndbuf_desc->is_vm) {
1861 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
1862 			return SMC_CLC_DECL_ERR_REGBUF;
1863 	}
1864 
1865 	/* reg the rmb */
1866 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
1867 		return SMC_CLC_DECL_ERR_REGBUF;
1868 
1869 	/* send CONFIRM LINK request to client over the RoCE fabric */
1870 	rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1871 	if (rc < 0)
1872 		return SMC_CLC_DECL_TIMEOUT_CL;
1873 
1874 	/* receive CONFIRM LINK response from client over the RoCE fabric */
1875 	qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1876 			      SMC_LLC_CONFIRM_LINK);
1877 	if (!qentry) {
1878 		struct smc_clc_msg_decline dclc;
1879 
1880 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1881 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1882 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1883 	}
1884 	smc_llc_save_peer_uid(qentry);
1885 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1886 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1887 	if (rc)
1888 		return SMC_CLC_DECL_RMBE_EC;
1889 
1890 	/* confirm_rkey is implicit on 1st contact */
1891 	smc->conn.rmb_desc->is_conf_rkey = true;
1892 
1893 	smc_llc_link_active(link);
1894 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1895 
1896 	if (link->lgr->max_links > 1) {
1897 		down_write(&link->lgr->llc_conf_mutex);
1898 		/* initial contact - try to establish second link */
1899 		smc_llc_srv_add_link(link, NULL);
1900 		up_write(&link->lgr->llc_conf_mutex);
1901 	}
1902 	return 0;
1903 }
1904 
1905 /* listen worker: finish */
1906 static void smc_listen_out(struct smc_sock *new_smc)
1907 {
1908 	struct smc_sock *lsmc = new_smc->listen_smc;
1909 	struct sock *newsmcsk = &new_smc->sk;
1910 
1911 	if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1912 		atomic_dec(&lsmc->queued_smc_hs);
1913 
1914 	if (lsmc->sk.sk_state == SMC_LISTEN) {
1915 		lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1916 		smc_accept_enqueue(&lsmc->sk, newsmcsk);
1917 		release_sock(&lsmc->sk);
1918 	} else { /* no longer listening */
1919 		smc_close_non_accepted(newsmcsk);
1920 	}
1921 
1922 	/* Wake up accept */
1923 	lsmc->sk.sk_data_ready(&lsmc->sk);
1924 	sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1925 }
1926 
1927 /* listen worker: finish in state connected */
1928 static void smc_listen_out_connected(struct smc_sock *new_smc)
1929 {
1930 	struct sock *newsmcsk = &new_smc->sk;
1931 
1932 	if (newsmcsk->sk_state == SMC_INIT)
1933 		newsmcsk->sk_state = SMC_ACTIVE;
1934 
1935 	smc_listen_out(new_smc);
1936 }
1937 
1938 /* listen worker: finish in error state */
1939 static void smc_listen_out_err(struct smc_sock *new_smc)
1940 {
1941 	struct sock *newsmcsk = &new_smc->sk;
1942 	struct net *net = sock_net(newsmcsk);
1943 
1944 	this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1945 	if (newsmcsk->sk_state == SMC_INIT)
1946 		sock_put(&new_smc->sk); /* passive closing */
1947 	newsmcsk->sk_state = SMC_CLOSED;
1948 
1949 	smc_listen_out(new_smc);
1950 }
1951 
1952 /* listen worker: decline and fall back if possible */
1953 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1954 			       int local_first, u8 version)
1955 {
1956 	/* RDMA setup failed, switch back to TCP */
1957 	smc_conn_abort(new_smc, local_first);
1958 	if (reason_code < 0 ||
1959 	    smc_switch_to_fallback(new_smc, reason_code)) {
1960 		/* error, no fallback possible */
1961 		smc_listen_out_err(new_smc);
1962 		return;
1963 	}
1964 	if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1965 		if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1966 			smc_listen_out_err(new_smc);
1967 			return;
1968 		}
1969 	}
1970 	smc_listen_out_connected(new_smc);
1971 }
1972 
1973 /* listen worker: version checking */
1974 static int smc_listen_v2_check(struct smc_sock *new_smc,
1975 			       struct smc_clc_msg_proposal *pclc,
1976 			       struct smc_init_info *ini)
1977 {
1978 	struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1979 	struct smc_clc_v2_extension *pclc_v2_ext;
1980 	int rc = SMC_CLC_DECL_PEERNOSMC;
1981 
1982 	ini->smc_type_v1 = pclc->hdr.typev1;
1983 	ini->smc_type_v2 = pclc->hdr.typev2;
1984 	ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1985 	ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1986 	if (pclc->hdr.version > SMC_V1) {
1987 		if (smcd_indicated(ini->smc_type_v2))
1988 			ini->smcd_version |= SMC_V2;
1989 		if (smcr_indicated(ini->smc_type_v2))
1990 			ini->smcr_version |= SMC_V2;
1991 	}
1992 	if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1993 		rc = SMC_CLC_DECL_PEERNOSMC;
1994 		goto out;
1995 	}
1996 	pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1997 	if (!pclc_v2_ext) {
1998 		ini->smcd_version &= ~SMC_V2;
1999 		ini->smcr_version &= ~SMC_V2;
2000 		rc = SMC_CLC_DECL_NOV2EXT;
2001 		goto out;
2002 	}
2003 	pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
2004 	if (ini->smcd_version & SMC_V2) {
2005 		if (!smc_ism_is_v2_capable()) {
2006 			ini->smcd_version &= ~SMC_V2;
2007 			rc = SMC_CLC_DECL_NOISM2SUPP;
2008 		} else if (!pclc_smcd_v2_ext) {
2009 			ini->smcd_version &= ~SMC_V2;
2010 			rc = SMC_CLC_DECL_NOV2DEXT;
2011 		} else if (!pclc_v2_ext->hdr.eid_cnt &&
2012 			   !pclc_v2_ext->hdr.flag.seid) {
2013 			ini->smcd_version &= ~SMC_V2;
2014 			rc = SMC_CLC_DECL_NOUEID;
2015 		}
2016 	}
2017 	if (ini->smcr_version & SMC_V2) {
2018 		if (!pclc_v2_ext->hdr.eid_cnt) {
2019 			ini->smcr_version &= ~SMC_V2;
2020 			rc = SMC_CLC_DECL_NOUEID;
2021 		}
2022 	}
2023 
2024 	ini->release_nr = pclc_v2_ext->hdr.flag.release;
2025 	if (pclc_v2_ext->hdr.flag.release > SMC_RELEASE)
2026 		ini->release_nr = SMC_RELEASE;
2027 
2028 out:
2029 	if (!ini->smcd_version && !ini->smcr_version)
2030 		return rc;
2031 
2032 	return 0;
2033 }
2034 
2035 /* listen worker: check prefixes */
2036 static int smc_listen_prfx_check(struct smc_sock *new_smc,
2037 				 struct smc_clc_msg_proposal *pclc)
2038 {
2039 	struct smc_clc_msg_proposal_prefix *pclc_prfx;
2040 	struct socket *newclcsock = new_smc->clcsock;
2041 
2042 	if (pclc->hdr.typev1 == SMC_TYPE_N)
2043 		return 0;
2044 	pclc_prfx = smc_clc_proposal_get_prefix(pclc);
2045 	if (smc_clc_prfx_match(newclcsock, pclc_prfx))
2046 		return SMC_CLC_DECL_DIFFPREFIX;
2047 
2048 	return 0;
2049 }
2050 
2051 /* listen worker: initialize connection and buffers */
2052 static int smc_listen_rdma_init(struct smc_sock *new_smc,
2053 				struct smc_init_info *ini)
2054 {
2055 	int rc;
2056 
2057 	/* allocate connection / link group */
2058 	rc = smc_conn_create(new_smc, ini);
2059 	if (rc)
2060 		return rc;
2061 
2062 	/* create send buffer and rmb */
2063 	if (smc_buf_create(new_smc, false)) {
2064 		smc_conn_abort(new_smc, ini->first_contact_local);
2065 		return SMC_CLC_DECL_MEM;
2066 	}
2067 
2068 	return 0;
2069 }
2070 
2071 /* listen worker: initialize connection and buffers for SMC-D */
2072 static int smc_listen_ism_init(struct smc_sock *new_smc,
2073 			       struct smc_init_info *ini)
2074 {
2075 	int rc;
2076 
2077 	rc = smc_conn_create(new_smc, ini);
2078 	if (rc)
2079 		return rc;
2080 
2081 	/* Create send and receive buffers */
2082 	rc = smc_buf_create(new_smc, true);
2083 	if (rc) {
2084 		smc_conn_abort(new_smc, ini->first_contact_local);
2085 		return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2086 					 SMC_CLC_DECL_MEM;
2087 	}
2088 
2089 	return 0;
2090 }
2091 
2092 static bool smc_is_already_selected(struct smcd_dev *smcd,
2093 				    struct smc_init_info *ini,
2094 				    int matches)
2095 {
2096 	int i;
2097 
2098 	for (i = 0; i < matches; i++)
2099 		if (smcd == ini->ism_dev[i])
2100 			return true;
2101 
2102 	return false;
2103 }
2104 
2105 /* check for ISM devices matching proposed ISM devices */
2106 static void smc_check_ism_v2_match(struct smc_init_info *ini,
2107 				   u16 proposed_chid,
2108 				   struct smcd_gid *proposed_gid,
2109 				   unsigned int *matches)
2110 {
2111 	struct smcd_dev *smcd;
2112 
2113 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2114 		if (smcd->going_away)
2115 			continue;
2116 		if (smc_is_already_selected(smcd, ini, *matches))
2117 			continue;
2118 		if (smc_ism_get_chid(smcd) == proposed_chid &&
2119 		    !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2120 			ini->ism_peer_gid[*matches].gid = proposed_gid->gid;
2121 			if (__smc_ism_is_emulated(proposed_chid))
2122 				ini->ism_peer_gid[*matches].gid_ext =
2123 							proposed_gid->gid_ext;
2124 				/* non-Emulated-ISM's peer gid_ext remains 0. */
2125 			ini->ism_dev[*matches] = smcd;
2126 			(*matches)++;
2127 			break;
2128 		}
2129 	}
2130 }
2131 
2132 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2133 {
2134 	if (!ini->rc)
2135 		ini->rc = rc;
2136 }
2137 
2138 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2139 					struct smc_clc_msg_proposal *pclc,
2140 					struct smc_init_info *ini)
2141 {
2142 	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2143 	struct smc_clc_v2_extension *smc_v2_ext;
2144 	struct smc_clc_msg_smcd *pclc_smcd;
2145 	unsigned int matches = 0;
2146 	struct smcd_gid smcd_gid;
2147 	u8 smcd_version;
2148 	u8 *eid = NULL;
2149 	int i, rc;
2150 	u16 chid;
2151 
2152 	if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2153 		goto not_found;
2154 
2155 	pclc_smcd = smc_get_clc_msg_smcd(pclc);
2156 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2157 	smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2158 
2159 	mutex_lock(&smcd_dev_list.mutex);
2160 	if (pclc_smcd->ism.chid) {
2161 		/* check for ISM device matching proposed native ISM device */
2162 		smcd_gid.gid = ntohll(pclc_smcd->ism.gid);
2163 		smcd_gid.gid_ext = 0;
2164 		smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2165 				       &smcd_gid, &matches);
2166 	}
2167 	for (i = 0; i < smc_v2_ext->hdr.ism_gid_cnt; i++) {
2168 		/* check for ISM devices matching proposed non-native ISM
2169 		 * devices
2170 		 */
2171 		smcd_gid.gid = ntohll(smcd_v2_ext->gidchid[i].gid);
2172 		smcd_gid.gid_ext = 0;
2173 		chid = ntohs(smcd_v2_ext->gidchid[i].chid);
2174 		if (__smc_ism_is_emulated(chid)) {
2175 			if ((i + 1) == smc_v2_ext->hdr.ism_gid_cnt ||
2176 			    chid != ntohs(smcd_v2_ext->gidchid[i + 1].chid))
2177 				/* each Emulated-ISM device takes two GID-CHID
2178 				 * entries and CHID of the second entry repeats
2179 				 * that of the first entry.
2180 				 *
2181 				 * So check if the next GID-CHID entry exists
2182 				 * and both two entries' CHIDs are the same.
2183 				 */
2184 				continue;
2185 			smcd_gid.gid_ext =
2186 				ntohll(smcd_v2_ext->gidchid[++i].gid);
2187 		}
2188 		smc_check_ism_v2_match(ini, chid, &smcd_gid, &matches);
2189 	}
2190 	mutex_unlock(&smcd_dev_list.mutex);
2191 
2192 	if (!ini->ism_dev[0]) {
2193 		smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2194 		goto not_found;
2195 	}
2196 
2197 	smc_ism_get_system_eid(&eid);
2198 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2199 			       smcd_v2_ext->system_eid, eid))
2200 		goto not_found;
2201 
2202 	/* separate - outside the smcd_dev_list.lock */
2203 	smcd_version = ini->smcd_version;
2204 	for (i = 0; i < matches; i++) {
2205 		ini->smcd_version = SMC_V2;
2206 		ini->is_smcd = true;
2207 		ini->ism_selected = i;
2208 		rc = smc_listen_ism_init(new_smc, ini);
2209 		if (rc) {
2210 			smc_find_ism_store_rc(rc, ini);
2211 			/* try next active ISM device */
2212 			continue;
2213 		}
2214 		return; /* matching and usable V2 ISM device found */
2215 	}
2216 	/* no V2 ISM device could be initialized */
2217 	ini->smcd_version = smcd_version;	/* restore original value */
2218 	ini->negotiated_eid[0] = 0;
2219 
2220 not_found:
2221 	ini->smcd_version &= ~SMC_V2;
2222 	ini->ism_dev[0] = NULL;
2223 	ini->is_smcd = false;
2224 }
2225 
2226 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2227 					struct smc_clc_msg_proposal *pclc,
2228 					struct smc_init_info *ini)
2229 {
2230 	struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2231 	int rc = 0;
2232 
2233 	/* check if ISM V1 is available */
2234 	if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2235 		goto not_found;
2236 	ini->is_smcd = true; /* prepare ISM check */
2237 	ini->ism_peer_gid[0].gid = ntohll(pclc_smcd->ism.gid);
2238 	ini->ism_peer_gid[0].gid_ext = 0;
2239 	rc = smc_find_ism_device(new_smc, ini);
2240 	if (rc)
2241 		goto not_found;
2242 	ini->ism_selected = 0;
2243 	rc = smc_listen_ism_init(new_smc, ini);
2244 	if (!rc)
2245 		return;		/* V1 ISM device found */
2246 
2247 not_found:
2248 	smc_find_ism_store_rc(rc, ini);
2249 	ini->smcd_version &= ~SMC_V1;
2250 	ini->ism_dev[0] = NULL;
2251 	ini->is_smcd = false;
2252 }
2253 
2254 /* listen worker: register buffers */
2255 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2256 {
2257 	struct smc_connection *conn = &new_smc->conn;
2258 
2259 	if (!local_first) {
2260 		/* reg sendbufs if they were vzalloced */
2261 		if (conn->sndbuf_desc->is_vm) {
2262 			if (smcr_lgr_reg_sndbufs(conn->lnk,
2263 						 conn->sndbuf_desc))
2264 				return SMC_CLC_DECL_ERR_REGBUF;
2265 		}
2266 		if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2267 			return SMC_CLC_DECL_ERR_REGBUF;
2268 	}
2269 
2270 	return 0;
2271 }
2272 
2273 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2274 					 struct smc_clc_msg_proposal *pclc,
2275 					 struct smc_init_info *ini)
2276 {
2277 	struct smc_clc_v2_extension *smc_v2_ext;
2278 	u8 smcr_version;
2279 	int rc;
2280 
2281 	if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2282 		goto not_found;
2283 
2284 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2285 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2286 		goto not_found;
2287 
2288 	/* prepare RDMA check */
2289 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2290 	memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2291 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2292 	ini->check_smcrv2 = true;
2293 	ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2294 	ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2295 	ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2296 	rc = smc_find_rdma_device(new_smc, ini);
2297 	if (rc) {
2298 		smc_find_ism_store_rc(rc, ini);
2299 		goto not_found;
2300 	}
2301 	if (!ini->smcrv2.uses_gateway)
2302 		memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2303 
2304 	smcr_version = ini->smcr_version;
2305 	ini->smcr_version = SMC_V2;
2306 	rc = smc_listen_rdma_init(new_smc, ini);
2307 	if (!rc) {
2308 		rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2309 		if (rc)
2310 			smc_conn_abort(new_smc, ini->first_contact_local);
2311 	}
2312 	if (!rc)
2313 		return;
2314 	ini->smcr_version = smcr_version;
2315 	smc_find_ism_store_rc(rc, ini);
2316 
2317 not_found:
2318 	ini->smcr_version &= ~SMC_V2;
2319 	ini->smcrv2.ib_dev_v2 = NULL;
2320 	ini->check_smcrv2 = false;
2321 }
2322 
2323 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2324 					struct smc_clc_msg_proposal *pclc,
2325 					struct smc_init_info *ini)
2326 {
2327 	int rc;
2328 
2329 	if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2330 		return SMC_CLC_DECL_NOSMCDEV;
2331 
2332 	/* prepare RDMA check */
2333 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2334 	memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2335 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2336 	rc = smc_find_rdma_device(new_smc, ini);
2337 	if (rc) {
2338 		/* no RDMA device found */
2339 		return SMC_CLC_DECL_NOSMCDEV;
2340 	}
2341 	rc = smc_listen_rdma_init(new_smc, ini);
2342 	if (rc)
2343 		return rc;
2344 	return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2345 }
2346 
2347 /* determine the local device matching to proposal */
2348 static int smc_listen_find_device(struct smc_sock *new_smc,
2349 				  struct smc_clc_msg_proposal *pclc,
2350 				  struct smc_init_info *ini)
2351 {
2352 	int prfx_rc;
2353 
2354 	/* check for ISM device matching V2 proposed device */
2355 	smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2356 	if (ini->ism_dev[0])
2357 		return 0;
2358 
2359 	/* check for matching IP prefix and subnet length (V1) */
2360 	prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2361 	if (prfx_rc)
2362 		smc_find_ism_store_rc(prfx_rc, ini);
2363 
2364 	/* get vlan id from IP device */
2365 	if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2366 		return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2367 
2368 	/* check for ISM device matching V1 proposed device */
2369 	if (!prfx_rc)
2370 		smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2371 	if (ini->ism_dev[0])
2372 		return 0;
2373 
2374 	if (!smcr_indicated(pclc->hdr.typev1) &&
2375 	    !smcr_indicated(pclc->hdr.typev2))
2376 		/* skip RDMA and decline */
2377 		return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2378 
2379 	/* check if RDMA V2 is available */
2380 	smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2381 	if (ini->smcrv2.ib_dev_v2)
2382 		return 0;
2383 
2384 	/* check if RDMA V1 is available */
2385 	if (!prfx_rc) {
2386 		int rc;
2387 
2388 		rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2389 		smc_find_ism_store_rc(rc, ini);
2390 		return (!rc) ? 0 : ini->rc;
2391 	}
2392 	return prfx_rc;
2393 }
2394 
2395 /* listen worker: finish RDMA setup */
2396 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2397 				  struct smc_clc_msg_accept_confirm *cclc,
2398 				  bool local_first,
2399 				  struct smc_init_info *ini)
2400 {
2401 	struct smc_link *link = new_smc->conn.lnk;
2402 	int reason_code = 0;
2403 
2404 	if (local_first)
2405 		smc_link_save_peer_info(link, cclc, ini);
2406 
2407 	if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2408 		return SMC_CLC_DECL_ERR_RTOK;
2409 
2410 	if (local_first) {
2411 		if (smc_ib_ready_link(link))
2412 			return SMC_CLC_DECL_ERR_RDYLNK;
2413 		/* QP confirmation over RoCE fabric */
2414 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2415 		reason_code = smcr_serv_conf_first_link(new_smc);
2416 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2417 	}
2418 	return reason_code;
2419 }
2420 
2421 /* setup for connection of server */
2422 static void smc_listen_work(struct work_struct *work)
2423 {
2424 	struct smc_sock *new_smc = container_of(work, struct smc_sock,
2425 						smc_listen_work);
2426 	struct socket *newclcsock = new_smc->clcsock;
2427 	struct smc_clc_msg_accept_confirm *cclc;
2428 	struct smc_clc_msg_proposal_area *buf;
2429 	struct smc_clc_msg_proposal *pclc;
2430 	struct smc_init_info *ini = NULL;
2431 	u8 proposal_version = SMC_V1;
2432 	u8 accept_version;
2433 	int rc = 0;
2434 
2435 	if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2436 		return smc_listen_out_err(new_smc);
2437 
2438 	if (new_smc->use_fallback) {
2439 		smc_listen_out_connected(new_smc);
2440 		return;
2441 	}
2442 
2443 	/* check if peer is smc capable */
2444 	if (!tcp_sk(newclcsock->sk)->syn_smc) {
2445 		rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2446 		if (rc)
2447 			smc_listen_out_err(new_smc);
2448 		else
2449 			smc_listen_out_connected(new_smc);
2450 		return;
2451 	}
2452 
2453 	/* do inband token exchange -
2454 	 * wait for and receive SMC Proposal CLC message
2455 	 */
2456 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2457 	if (!buf) {
2458 		rc = SMC_CLC_DECL_MEM;
2459 		goto out_decl;
2460 	}
2461 	pclc = (struct smc_clc_msg_proposal *)buf;
2462 	rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2463 			      SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2464 	if (rc)
2465 		goto out_decl;
2466 
2467 	if (pclc->hdr.version > SMC_V1)
2468 		proposal_version = SMC_V2;
2469 
2470 	/* IPSec connections opt out of SMC optimizations */
2471 	if (using_ipsec(new_smc)) {
2472 		rc = SMC_CLC_DECL_IPSEC;
2473 		goto out_decl;
2474 	}
2475 
2476 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2477 	if (!ini) {
2478 		rc = SMC_CLC_DECL_MEM;
2479 		goto out_decl;
2480 	}
2481 
2482 	/* initial version checking */
2483 	rc = smc_listen_v2_check(new_smc, pclc, ini);
2484 	if (rc)
2485 		goto out_decl;
2486 
2487 	rc = smc_clc_srv_v2x_features_validate(new_smc, pclc, ini);
2488 	if (rc)
2489 		goto out_decl;
2490 
2491 	mutex_lock(&smc_server_lgr_pending);
2492 	smc_close_init(new_smc);
2493 	smc_rx_init(new_smc);
2494 	smc_tx_init(new_smc);
2495 
2496 	/* determine ISM or RoCE device used for connection */
2497 	rc = smc_listen_find_device(new_smc, pclc, ini);
2498 	if (rc)
2499 		goto out_unlock;
2500 
2501 	/* send SMC Accept CLC message */
2502 	accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2503 	rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2504 				 accept_version, ini->negotiated_eid, ini);
2505 	if (rc)
2506 		goto out_unlock;
2507 
2508 	/* SMC-D does not need this lock any more */
2509 	if (ini->is_smcd)
2510 		mutex_unlock(&smc_server_lgr_pending);
2511 
2512 	/* receive SMC Confirm CLC message */
2513 	memset(buf, 0, sizeof(*buf));
2514 	cclc = (struct smc_clc_msg_accept_confirm *)buf;
2515 	rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2516 			      SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2517 	if (rc) {
2518 		if (!ini->is_smcd)
2519 			goto out_unlock;
2520 		goto out_decl;
2521 	}
2522 
2523 	rc = smc_clc_v2x_features_confirm_check(cclc, ini);
2524 	if (rc) {
2525 		if (!ini->is_smcd)
2526 			goto out_unlock;
2527 		goto out_decl;
2528 	}
2529 
2530 	/* fce smc release version is needed in smc_listen_rdma_finish,
2531 	 * so save fce info here.
2532 	 */
2533 	smc_conn_save_peer_info_fce(new_smc, cclc);
2534 
2535 	/* finish worker */
2536 	if (!ini->is_smcd) {
2537 		rc = smc_listen_rdma_finish(new_smc, cclc,
2538 					    ini->first_contact_local, ini);
2539 		if (rc)
2540 			goto out_unlock;
2541 		mutex_unlock(&smc_server_lgr_pending);
2542 	}
2543 	smc_conn_save_peer_info(new_smc, cclc);
2544 	smc_listen_out_connected(new_smc);
2545 	SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2546 	goto out_free;
2547 
2548 out_unlock:
2549 	mutex_unlock(&smc_server_lgr_pending);
2550 out_decl:
2551 	smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2552 			   proposal_version);
2553 out_free:
2554 	kfree(ini);
2555 	kfree(buf);
2556 }
2557 
2558 static void smc_tcp_listen_work(struct work_struct *work)
2559 {
2560 	struct smc_sock *lsmc = container_of(work, struct smc_sock,
2561 					     tcp_listen_work);
2562 	struct sock *lsk = &lsmc->sk;
2563 	struct smc_sock *new_smc;
2564 	int rc = 0;
2565 
2566 	lock_sock(lsk);
2567 	while (lsk->sk_state == SMC_LISTEN) {
2568 		rc = smc_clcsock_accept(lsmc, &new_smc);
2569 		if (rc) /* clcsock accept queue empty or error */
2570 			goto out;
2571 		if (!new_smc)
2572 			continue;
2573 
2574 		if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2575 			atomic_inc(&lsmc->queued_smc_hs);
2576 
2577 		new_smc->listen_smc = lsmc;
2578 		new_smc->use_fallback = lsmc->use_fallback;
2579 		new_smc->fallback_rsn = lsmc->fallback_rsn;
2580 		sock_hold(lsk); /* sock_put in smc_listen_work */
2581 		INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2582 		smc_copy_sock_settings_to_smc(new_smc);
2583 		sock_hold(&new_smc->sk); /* sock_put in passive closing */
2584 		if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2585 			sock_put(&new_smc->sk);
2586 	}
2587 
2588 out:
2589 	release_sock(lsk);
2590 	sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2591 }
2592 
2593 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2594 {
2595 	struct smc_sock *lsmc;
2596 
2597 	read_lock_bh(&listen_clcsock->sk_callback_lock);
2598 	lsmc = smc_clcsock_user_data(listen_clcsock);
2599 	if (!lsmc)
2600 		goto out;
2601 	lsmc->clcsk_data_ready(listen_clcsock);
2602 	if (lsmc->sk.sk_state == SMC_LISTEN) {
2603 		sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2604 		if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2605 			sock_put(&lsmc->sk);
2606 	}
2607 out:
2608 	read_unlock_bh(&listen_clcsock->sk_callback_lock);
2609 }
2610 
2611 static int smc_listen(struct socket *sock, int backlog)
2612 {
2613 	struct sock *sk = sock->sk;
2614 	struct smc_sock *smc;
2615 	int rc;
2616 
2617 	smc = smc_sk(sk);
2618 	lock_sock(sk);
2619 
2620 	rc = -EINVAL;
2621 	if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2622 	    smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2623 		goto out;
2624 
2625 	rc = 0;
2626 	if (sk->sk_state == SMC_LISTEN) {
2627 		sk->sk_max_ack_backlog = backlog;
2628 		goto out;
2629 	}
2630 	/* some socket options are handled in core, so we could not apply
2631 	 * them to the clc socket -- copy smc socket options to clc socket
2632 	 */
2633 	smc_copy_sock_settings_to_clc(smc);
2634 	if (!smc->use_fallback)
2635 		tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2636 
2637 	/* save original sk_data_ready function and establish
2638 	 * smc-specific sk_data_ready function
2639 	 */
2640 	write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2641 	smc->clcsock->sk->sk_user_data =
2642 		(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2643 	smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2644 			       smc_clcsock_data_ready, &smc->clcsk_data_ready);
2645 	write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2646 
2647 	/* save original ops */
2648 	smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2649 
2650 	smc->af_ops = *smc->ori_af_ops;
2651 	smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2652 
2653 	inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2654 
2655 	if (smc->limit_smc_hs)
2656 		tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2657 
2658 	rc = kernel_listen(smc->clcsock, backlog);
2659 	if (rc) {
2660 		write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2661 		smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2662 				       &smc->clcsk_data_ready);
2663 		smc->clcsock->sk->sk_user_data = NULL;
2664 		write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2665 		goto out;
2666 	}
2667 	sk->sk_max_ack_backlog = backlog;
2668 	sk->sk_ack_backlog = 0;
2669 	sk->sk_state = SMC_LISTEN;
2670 
2671 out:
2672 	release_sock(sk);
2673 	return rc;
2674 }
2675 
2676 static int smc_accept(struct socket *sock, struct socket *new_sock,
2677 		      int flags, bool kern)
2678 {
2679 	struct sock *sk = sock->sk, *nsk;
2680 	DECLARE_WAITQUEUE(wait, current);
2681 	struct smc_sock *lsmc;
2682 	long timeo;
2683 	int rc = 0;
2684 
2685 	lsmc = smc_sk(sk);
2686 	sock_hold(sk); /* sock_put below */
2687 	lock_sock(sk);
2688 
2689 	if (lsmc->sk.sk_state != SMC_LISTEN) {
2690 		rc = -EINVAL;
2691 		release_sock(sk);
2692 		goto out;
2693 	}
2694 
2695 	/* Wait for an incoming connection */
2696 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2697 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
2698 	while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2699 		set_current_state(TASK_INTERRUPTIBLE);
2700 		if (!timeo) {
2701 			rc = -EAGAIN;
2702 			break;
2703 		}
2704 		release_sock(sk);
2705 		timeo = schedule_timeout(timeo);
2706 		/* wakeup by sk_data_ready in smc_listen_work() */
2707 		sched_annotate_sleep();
2708 		lock_sock(sk);
2709 		if (signal_pending(current)) {
2710 			rc = sock_intr_errno(timeo);
2711 			break;
2712 		}
2713 	}
2714 	set_current_state(TASK_RUNNING);
2715 	remove_wait_queue(sk_sleep(sk), &wait);
2716 
2717 	if (!rc)
2718 		rc = sock_error(nsk);
2719 	release_sock(sk);
2720 	if (rc)
2721 		goto out;
2722 
2723 	if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
2724 		/* wait till data arrives on the socket */
2725 		timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2726 								MSEC_PER_SEC);
2727 		if (smc_sk(nsk)->use_fallback) {
2728 			struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2729 
2730 			lock_sock(clcsk);
2731 			if (skb_queue_empty(&clcsk->sk_receive_queue))
2732 				sk_wait_data(clcsk, &timeo, NULL);
2733 			release_sock(clcsk);
2734 		} else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2735 			lock_sock(nsk);
2736 			smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2737 			release_sock(nsk);
2738 		}
2739 	}
2740 
2741 out:
2742 	sock_put(sk); /* sock_hold above */
2743 	return rc;
2744 }
2745 
2746 static int smc_getname(struct socket *sock, struct sockaddr *addr,
2747 		       int peer)
2748 {
2749 	struct smc_sock *smc;
2750 
2751 	if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2752 	    (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2753 		return -ENOTCONN;
2754 
2755 	smc = smc_sk(sock->sk);
2756 
2757 	return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2758 }
2759 
2760 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2761 {
2762 	struct sock *sk = sock->sk;
2763 	struct smc_sock *smc;
2764 	int rc;
2765 
2766 	smc = smc_sk(sk);
2767 	lock_sock(sk);
2768 
2769 	/* SMC does not support connect with fastopen */
2770 	if (msg->msg_flags & MSG_FASTOPEN) {
2771 		/* not connected yet, fallback */
2772 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2773 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2774 			if (rc)
2775 				goto out;
2776 		} else {
2777 			rc = -EINVAL;
2778 			goto out;
2779 		}
2780 	} else if ((sk->sk_state != SMC_ACTIVE) &&
2781 		   (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2782 		   (sk->sk_state != SMC_INIT)) {
2783 		rc = -EPIPE;
2784 		goto out;
2785 	}
2786 
2787 	if (smc->use_fallback) {
2788 		rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2789 	} else {
2790 		rc = smc_tx_sendmsg(smc, msg, len);
2791 		SMC_STAT_TX_PAYLOAD(smc, len, rc);
2792 	}
2793 out:
2794 	release_sock(sk);
2795 	return rc;
2796 }
2797 
2798 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2799 		       int flags)
2800 {
2801 	struct sock *sk = sock->sk;
2802 	struct smc_sock *smc;
2803 	int rc = -ENOTCONN;
2804 
2805 	smc = smc_sk(sk);
2806 	lock_sock(sk);
2807 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2808 		/* socket was connected before, no more data to read */
2809 		rc = 0;
2810 		goto out;
2811 	}
2812 	if ((sk->sk_state == SMC_INIT) ||
2813 	    (sk->sk_state == SMC_LISTEN) ||
2814 	    (sk->sk_state == SMC_CLOSED))
2815 		goto out;
2816 
2817 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2818 		rc = 0;
2819 		goto out;
2820 	}
2821 
2822 	if (smc->use_fallback) {
2823 		rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2824 	} else {
2825 		msg->msg_namelen = 0;
2826 		rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2827 		SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2828 	}
2829 
2830 out:
2831 	release_sock(sk);
2832 	return rc;
2833 }
2834 
2835 static __poll_t smc_accept_poll(struct sock *parent)
2836 {
2837 	struct smc_sock *isk = smc_sk(parent);
2838 	__poll_t mask = 0;
2839 
2840 	spin_lock(&isk->accept_q_lock);
2841 	if (!list_empty(&isk->accept_q))
2842 		mask = EPOLLIN | EPOLLRDNORM;
2843 	spin_unlock(&isk->accept_q_lock);
2844 
2845 	return mask;
2846 }
2847 
2848 static __poll_t smc_poll(struct file *file, struct socket *sock,
2849 			     poll_table *wait)
2850 {
2851 	struct sock *sk = sock->sk;
2852 	struct smc_sock *smc;
2853 	__poll_t mask = 0;
2854 
2855 	if (!sk)
2856 		return EPOLLNVAL;
2857 
2858 	smc = smc_sk(sock->sk);
2859 	if (smc->use_fallback) {
2860 		/* delegate to CLC child sock */
2861 		mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2862 		sk->sk_err = smc->clcsock->sk->sk_err;
2863 	} else {
2864 		if (sk->sk_state != SMC_CLOSED)
2865 			sock_poll_wait(file, sock, wait);
2866 		if (sk->sk_err)
2867 			mask |= EPOLLERR;
2868 		if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2869 		    (sk->sk_state == SMC_CLOSED))
2870 			mask |= EPOLLHUP;
2871 		if (sk->sk_state == SMC_LISTEN) {
2872 			/* woken up by sk_data_ready in smc_listen_work() */
2873 			mask |= smc_accept_poll(sk);
2874 		} else if (smc->use_fallback) { /* as result of connect_work()*/
2875 			mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2876 							   wait);
2877 			sk->sk_err = smc->clcsock->sk->sk_err;
2878 		} else {
2879 			if ((sk->sk_state != SMC_INIT &&
2880 			     atomic_read(&smc->conn.sndbuf_space)) ||
2881 			    sk->sk_shutdown & SEND_SHUTDOWN) {
2882 				mask |= EPOLLOUT | EPOLLWRNORM;
2883 			} else {
2884 				sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2885 				set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2886 			}
2887 			if (atomic_read(&smc->conn.bytes_to_rcv))
2888 				mask |= EPOLLIN | EPOLLRDNORM;
2889 			if (sk->sk_shutdown & RCV_SHUTDOWN)
2890 				mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2891 			if (sk->sk_state == SMC_APPCLOSEWAIT1)
2892 				mask |= EPOLLIN;
2893 			if (smc->conn.urg_state == SMC_URG_VALID)
2894 				mask |= EPOLLPRI;
2895 		}
2896 	}
2897 
2898 	return mask;
2899 }
2900 
2901 static int smc_shutdown(struct socket *sock, int how)
2902 {
2903 	struct sock *sk = sock->sk;
2904 	bool do_shutdown = true;
2905 	struct smc_sock *smc;
2906 	int rc = -EINVAL;
2907 	int old_state;
2908 	int rc1 = 0;
2909 
2910 	smc = smc_sk(sk);
2911 
2912 	if ((how < SHUT_RD) || (how > SHUT_RDWR))
2913 		return rc;
2914 
2915 	lock_sock(sk);
2916 
2917 	if (sock->state == SS_CONNECTING) {
2918 		if (sk->sk_state == SMC_ACTIVE)
2919 			sock->state = SS_CONNECTED;
2920 		else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2921 			 sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2922 			 sk->sk_state == SMC_APPCLOSEWAIT1 ||
2923 			 sk->sk_state == SMC_APPCLOSEWAIT2 ||
2924 			 sk->sk_state == SMC_APPFINCLOSEWAIT)
2925 			sock->state = SS_DISCONNECTING;
2926 	}
2927 
2928 	rc = -ENOTCONN;
2929 	if ((sk->sk_state != SMC_ACTIVE) &&
2930 	    (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2931 	    (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2932 	    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2933 	    (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2934 	    (sk->sk_state != SMC_APPFINCLOSEWAIT))
2935 		goto out;
2936 	if (smc->use_fallback) {
2937 		rc = kernel_sock_shutdown(smc->clcsock, how);
2938 		sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2939 		if (sk->sk_shutdown == SHUTDOWN_MASK) {
2940 			sk->sk_state = SMC_CLOSED;
2941 			sk->sk_socket->state = SS_UNCONNECTED;
2942 			sock_put(sk);
2943 		}
2944 		goto out;
2945 	}
2946 	switch (how) {
2947 	case SHUT_RDWR:		/* shutdown in both directions */
2948 		old_state = sk->sk_state;
2949 		rc = smc_close_active(smc);
2950 		if (old_state == SMC_ACTIVE &&
2951 		    sk->sk_state == SMC_PEERCLOSEWAIT1)
2952 			do_shutdown = false;
2953 		break;
2954 	case SHUT_WR:
2955 		rc = smc_close_shutdown_write(smc);
2956 		break;
2957 	case SHUT_RD:
2958 		rc = 0;
2959 		/* nothing more to do because peer is not involved */
2960 		break;
2961 	}
2962 	if (do_shutdown && smc->clcsock)
2963 		rc1 = kernel_sock_shutdown(smc->clcsock, how);
2964 	/* map sock_shutdown_cmd constants to sk_shutdown value range */
2965 	sk->sk_shutdown |= how + 1;
2966 
2967 	if (sk->sk_state == SMC_CLOSED)
2968 		sock->state = SS_UNCONNECTED;
2969 	else
2970 		sock->state = SS_DISCONNECTING;
2971 out:
2972 	release_sock(sk);
2973 	return rc ? rc : rc1;
2974 }
2975 
2976 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2977 			    char __user *optval, int __user *optlen)
2978 {
2979 	struct smc_sock *smc;
2980 	int val, len;
2981 
2982 	smc = smc_sk(sock->sk);
2983 
2984 	if (get_user(len, optlen))
2985 		return -EFAULT;
2986 
2987 	len = min_t(int, len, sizeof(int));
2988 
2989 	if (len < 0)
2990 		return -EINVAL;
2991 
2992 	switch (optname) {
2993 	case SMC_LIMIT_HS:
2994 		val = smc->limit_smc_hs;
2995 		break;
2996 	default:
2997 		return -EOPNOTSUPP;
2998 	}
2999 
3000 	if (put_user(len, optlen))
3001 		return -EFAULT;
3002 	if (copy_to_user(optval, &val, len))
3003 		return -EFAULT;
3004 
3005 	return 0;
3006 }
3007 
3008 static int __smc_setsockopt(struct socket *sock, int level, int optname,
3009 			    sockptr_t optval, unsigned int optlen)
3010 {
3011 	struct sock *sk = sock->sk;
3012 	struct smc_sock *smc;
3013 	int val, rc;
3014 
3015 	smc = smc_sk(sk);
3016 
3017 	lock_sock(sk);
3018 	switch (optname) {
3019 	case SMC_LIMIT_HS:
3020 		if (optlen < sizeof(int)) {
3021 			rc = -EINVAL;
3022 			break;
3023 		}
3024 		if (copy_from_sockptr(&val, optval, sizeof(int))) {
3025 			rc = -EFAULT;
3026 			break;
3027 		}
3028 
3029 		smc->limit_smc_hs = !!val;
3030 		rc = 0;
3031 		break;
3032 	default:
3033 		rc = -EOPNOTSUPP;
3034 		break;
3035 	}
3036 	release_sock(sk);
3037 
3038 	return rc;
3039 }
3040 
3041 static int smc_setsockopt(struct socket *sock, int level, int optname,
3042 			  sockptr_t optval, unsigned int optlen)
3043 {
3044 	struct sock *sk = sock->sk;
3045 	struct smc_sock *smc;
3046 	int val, rc;
3047 
3048 	if (level == SOL_TCP && optname == TCP_ULP)
3049 		return -EOPNOTSUPP;
3050 	else if (level == SOL_SMC)
3051 		return __smc_setsockopt(sock, level, optname, optval, optlen);
3052 
3053 	smc = smc_sk(sk);
3054 
3055 	/* generic setsockopts reaching us here always apply to the
3056 	 * CLC socket
3057 	 */
3058 	mutex_lock(&smc->clcsock_release_lock);
3059 	if (!smc->clcsock) {
3060 		mutex_unlock(&smc->clcsock_release_lock);
3061 		return -EBADF;
3062 	}
3063 	if (unlikely(!smc->clcsock->ops->setsockopt))
3064 		rc = -EOPNOTSUPP;
3065 	else
3066 		rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
3067 						   optval, optlen);
3068 	if (smc->clcsock->sk->sk_err) {
3069 		sk->sk_err = smc->clcsock->sk->sk_err;
3070 		sk_error_report(sk);
3071 	}
3072 	mutex_unlock(&smc->clcsock_release_lock);
3073 
3074 	if (optlen < sizeof(int))
3075 		return -EINVAL;
3076 	if (copy_from_sockptr(&val, optval, sizeof(int)))
3077 		return -EFAULT;
3078 
3079 	lock_sock(sk);
3080 	if (rc || smc->use_fallback)
3081 		goto out;
3082 	switch (optname) {
3083 	case TCP_FASTOPEN:
3084 	case TCP_FASTOPEN_CONNECT:
3085 	case TCP_FASTOPEN_KEY:
3086 	case TCP_FASTOPEN_NO_COOKIE:
3087 		/* option not supported by SMC */
3088 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
3089 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
3090 		} else {
3091 			rc = -EINVAL;
3092 		}
3093 		break;
3094 	case TCP_NODELAY:
3095 		if (sk->sk_state != SMC_INIT &&
3096 		    sk->sk_state != SMC_LISTEN &&
3097 		    sk->sk_state != SMC_CLOSED) {
3098 			if (val) {
3099 				SMC_STAT_INC(smc, ndly_cnt);
3100 				smc_tx_pending(&smc->conn);
3101 				cancel_delayed_work(&smc->conn.tx_work);
3102 			}
3103 		}
3104 		break;
3105 	case TCP_CORK:
3106 		if (sk->sk_state != SMC_INIT &&
3107 		    sk->sk_state != SMC_LISTEN &&
3108 		    sk->sk_state != SMC_CLOSED) {
3109 			if (!val) {
3110 				SMC_STAT_INC(smc, cork_cnt);
3111 				smc_tx_pending(&smc->conn);
3112 				cancel_delayed_work(&smc->conn.tx_work);
3113 			}
3114 		}
3115 		break;
3116 	case TCP_DEFER_ACCEPT:
3117 		smc->sockopt_defer_accept = val;
3118 		break;
3119 	default:
3120 		break;
3121 	}
3122 out:
3123 	release_sock(sk);
3124 
3125 	return rc;
3126 }
3127 
3128 static int smc_getsockopt(struct socket *sock, int level, int optname,
3129 			  char __user *optval, int __user *optlen)
3130 {
3131 	struct smc_sock *smc;
3132 	int rc;
3133 
3134 	if (level == SOL_SMC)
3135 		return __smc_getsockopt(sock, level, optname, optval, optlen);
3136 
3137 	smc = smc_sk(sock->sk);
3138 	mutex_lock(&smc->clcsock_release_lock);
3139 	if (!smc->clcsock) {
3140 		mutex_unlock(&smc->clcsock_release_lock);
3141 		return -EBADF;
3142 	}
3143 	/* socket options apply to the CLC socket */
3144 	if (unlikely(!smc->clcsock->ops->getsockopt)) {
3145 		mutex_unlock(&smc->clcsock_release_lock);
3146 		return -EOPNOTSUPP;
3147 	}
3148 	rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3149 					   optval, optlen);
3150 	mutex_unlock(&smc->clcsock_release_lock);
3151 	return rc;
3152 }
3153 
3154 static int smc_ioctl(struct socket *sock, unsigned int cmd,
3155 		     unsigned long arg)
3156 {
3157 	union smc_host_cursor cons, urg;
3158 	struct smc_connection *conn;
3159 	struct smc_sock *smc;
3160 	int answ;
3161 
3162 	smc = smc_sk(sock->sk);
3163 	conn = &smc->conn;
3164 	lock_sock(&smc->sk);
3165 	if (smc->use_fallback) {
3166 		if (!smc->clcsock) {
3167 			release_sock(&smc->sk);
3168 			return -EBADF;
3169 		}
3170 		answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3171 		release_sock(&smc->sk);
3172 		return answ;
3173 	}
3174 	switch (cmd) {
3175 	case SIOCINQ: /* same as FIONREAD */
3176 		if (smc->sk.sk_state == SMC_LISTEN) {
3177 			release_sock(&smc->sk);
3178 			return -EINVAL;
3179 		}
3180 		if (smc->sk.sk_state == SMC_INIT ||
3181 		    smc->sk.sk_state == SMC_CLOSED)
3182 			answ = 0;
3183 		else
3184 			answ = atomic_read(&smc->conn.bytes_to_rcv);
3185 		break;
3186 	case SIOCOUTQ:
3187 		/* output queue size (not send + not acked) */
3188 		if (smc->sk.sk_state == SMC_LISTEN) {
3189 			release_sock(&smc->sk);
3190 			return -EINVAL;
3191 		}
3192 		if (smc->sk.sk_state == SMC_INIT ||
3193 		    smc->sk.sk_state == SMC_CLOSED)
3194 			answ = 0;
3195 		else
3196 			answ = smc->conn.sndbuf_desc->len -
3197 					atomic_read(&smc->conn.sndbuf_space);
3198 		break;
3199 	case SIOCOUTQNSD:
3200 		/* output queue size (not send only) */
3201 		if (smc->sk.sk_state == SMC_LISTEN) {
3202 			release_sock(&smc->sk);
3203 			return -EINVAL;
3204 		}
3205 		if (smc->sk.sk_state == SMC_INIT ||
3206 		    smc->sk.sk_state == SMC_CLOSED)
3207 			answ = 0;
3208 		else
3209 			answ = smc_tx_prepared_sends(&smc->conn);
3210 		break;
3211 	case SIOCATMARK:
3212 		if (smc->sk.sk_state == SMC_LISTEN) {
3213 			release_sock(&smc->sk);
3214 			return -EINVAL;
3215 		}
3216 		if (smc->sk.sk_state == SMC_INIT ||
3217 		    smc->sk.sk_state == SMC_CLOSED) {
3218 			answ = 0;
3219 		} else {
3220 			smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3221 			smc_curs_copy(&urg, &conn->urg_curs, conn);
3222 			answ = smc_curs_diff(conn->rmb_desc->len,
3223 					     &cons, &urg) == 1;
3224 		}
3225 		break;
3226 	default:
3227 		release_sock(&smc->sk);
3228 		return -ENOIOCTLCMD;
3229 	}
3230 	release_sock(&smc->sk);
3231 
3232 	return put_user(answ, (int __user *)arg);
3233 }
3234 
3235 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3236  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3237  * updates till whenever a respective page has been fully processed.
3238  * Note that subsequent recv() calls have to wait till all splice() processing
3239  * completed.
3240  */
3241 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3242 			       struct pipe_inode_info *pipe, size_t len,
3243 			       unsigned int flags)
3244 {
3245 	struct sock *sk = sock->sk;
3246 	struct smc_sock *smc;
3247 	int rc = -ENOTCONN;
3248 
3249 	smc = smc_sk(sk);
3250 	lock_sock(sk);
3251 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3252 		/* socket was connected before, no more data to read */
3253 		rc = 0;
3254 		goto out;
3255 	}
3256 	if (sk->sk_state == SMC_INIT ||
3257 	    sk->sk_state == SMC_LISTEN ||
3258 	    sk->sk_state == SMC_CLOSED)
3259 		goto out;
3260 
3261 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3262 		rc = 0;
3263 		goto out;
3264 	}
3265 
3266 	if (smc->use_fallback) {
3267 		rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3268 						    pipe, len, flags);
3269 	} else {
3270 		if (*ppos) {
3271 			rc = -ESPIPE;
3272 			goto out;
3273 		}
3274 		if (flags & SPLICE_F_NONBLOCK)
3275 			flags = MSG_DONTWAIT;
3276 		else
3277 			flags = 0;
3278 		SMC_STAT_INC(smc, splice_cnt);
3279 		rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3280 	}
3281 out:
3282 	release_sock(sk);
3283 
3284 	return rc;
3285 }
3286 
3287 /* must look like tcp */
3288 static const struct proto_ops smc_sock_ops = {
3289 	.family		= PF_SMC,
3290 	.owner		= THIS_MODULE,
3291 	.release	= smc_release,
3292 	.bind		= smc_bind,
3293 	.connect	= smc_connect,
3294 	.socketpair	= sock_no_socketpair,
3295 	.accept		= smc_accept,
3296 	.getname	= smc_getname,
3297 	.poll		= smc_poll,
3298 	.ioctl		= smc_ioctl,
3299 	.listen		= smc_listen,
3300 	.shutdown	= smc_shutdown,
3301 	.setsockopt	= smc_setsockopt,
3302 	.getsockopt	= smc_getsockopt,
3303 	.sendmsg	= smc_sendmsg,
3304 	.recvmsg	= smc_recvmsg,
3305 	.mmap		= sock_no_mmap,
3306 	.splice_read	= smc_splice_read,
3307 };
3308 
3309 static int __smc_create(struct net *net, struct socket *sock, int protocol,
3310 			int kern, struct socket *clcsock)
3311 {
3312 	int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3313 	struct smc_sock *smc;
3314 	struct sock *sk;
3315 	int rc;
3316 
3317 	rc = -ESOCKTNOSUPPORT;
3318 	if (sock->type != SOCK_STREAM)
3319 		goto out;
3320 
3321 	rc = -EPROTONOSUPPORT;
3322 	if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3323 		goto out;
3324 
3325 	rc = -ENOBUFS;
3326 	sock->ops = &smc_sock_ops;
3327 	sock->state = SS_UNCONNECTED;
3328 	sk = smc_sock_alloc(net, sock, protocol);
3329 	if (!sk)
3330 		goto out;
3331 
3332 	/* create internal TCP socket for CLC handshake and fallback */
3333 	smc = smc_sk(sk);
3334 	smc->use_fallback = false; /* assume rdma capability first */
3335 	smc->fallback_rsn = 0;
3336 
3337 	/* default behavior from limit_smc_hs in every net namespace */
3338 	smc->limit_smc_hs = net->smc.limit_smc_hs;
3339 
3340 	rc = 0;
3341 	if (!clcsock) {
3342 		rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3343 				      &smc->clcsock);
3344 		if (rc) {
3345 			sk_common_release(sk);
3346 			goto out;
3347 		}
3348 
3349 		/* smc_clcsock_release() does not wait smc->clcsock->sk's
3350 		 * destruction;  its sk_state might not be TCP_CLOSE after
3351 		 * smc->sk is close()d, and TCP timers can be fired later,
3352 		 * which need net ref.
3353 		 */
3354 		sk = smc->clcsock->sk;
3355 		__netns_tracker_free(net, &sk->ns_tracker, false);
3356 		sk->sk_net_refcnt = 1;
3357 		get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
3358 		sock_inuse_add(net, 1);
3359 	} else {
3360 		smc->clcsock = clcsock;
3361 	}
3362 
3363 out:
3364 	return rc;
3365 }
3366 
3367 static int smc_create(struct net *net, struct socket *sock, int protocol,
3368 		      int kern)
3369 {
3370 	return __smc_create(net, sock, protocol, kern, NULL);
3371 }
3372 
3373 static const struct net_proto_family smc_sock_family_ops = {
3374 	.family	= PF_SMC,
3375 	.owner	= THIS_MODULE,
3376 	.create	= smc_create,
3377 };
3378 
3379 static int smc_ulp_init(struct sock *sk)
3380 {
3381 	struct socket *tcp = sk->sk_socket;
3382 	struct net *net = sock_net(sk);
3383 	struct socket *smcsock;
3384 	int protocol, ret;
3385 
3386 	/* only TCP can be replaced */
3387 	if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3388 	    (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3389 		return -ESOCKTNOSUPPORT;
3390 	/* don't handle wq now */
3391 	if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3392 		return -ENOTCONN;
3393 
3394 	if (sk->sk_family == AF_INET)
3395 		protocol = SMCPROTO_SMC;
3396 	else
3397 		protocol = SMCPROTO_SMC6;
3398 
3399 	smcsock = sock_alloc();
3400 	if (!smcsock)
3401 		return -ENFILE;
3402 
3403 	smcsock->type = SOCK_STREAM;
3404 	__module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3405 	ret = __smc_create(net, smcsock, protocol, 1, tcp);
3406 	if (ret) {
3407 		sock_release(smcsock); /* module_put() which ops won't be NULL */
3408 		return ret;
3409 	}
3410 
3411 	/* replace tcp socket to smc */
3412 	smcsock->file = tcp->file;
3413 	smcsock->file->private_data = smcsock;
3414 	smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3415 	smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3416 	tcp->file = NULL;
3417 
3418 	return ret;
3419 }
3420 
3421 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3422 			  const gfp_t priority)
3423 {
3424 	struct inet_connection_sock *icsk = inet_csk(newsk);
3425 
3426 	/* don't inherit ulp ops to child when listen */
3427 	icsk->icsk_ulp_ops = NULL;
3428 }
3429 
3430 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3431 	.name		= "smc",
3432 	.owner		= THIS_MODULE,
3433 	.init		= smc_ulp_init,
3434 	.clone		= smc_ulp_clone,
3435 };
3436 
3437 unsigned int smc_net_id;
3438 
3439 static __net_init int smc_net_init(struct net *net)
3440 {
3441 	int rc;
3442 
3443 	rc = smc_sysctl_net_init(net);
3444 	if (rc)
3445 		return rc;
3446 	return smc_pnet_net_init(net);
3447 }
3448 
3449 static void __net_exit smc_net_exit(struct net *net)
3450 {
3451 	smc_sysctl_net_exit(net);
3452 	smc_pnet_net_exit(net);
3453 }
3454 
3455 static __net_init int smc_net_stat_init(struct net *net)
3456 {
3457 	return smc_stats_init(net);
3458 }
3459 
3460 static void __net_exit smc_net_stat_exit(struct net *net)
3461 {
3462 	smc_stats_exit(net);
3463 }
3464 
3465 static struct pernet_operations smc_net_ops = {
3466 	.init = smc_net_init,
3467 	.exit = smc_net_exit,
3468 	.id   = &smc_net_id,
3469 	.size = sizeof(struct smc_net),
3470 };
3471 
3472 static struct pernet_operations smc_net_stat_ops = {
3473 	.init = smc_net_stat_init,
3474 	.exit = smc_net_stat_exit,
3475 };
3476 
3477 static int __init smc_init(void)
3478 {
3479 	int rc;
3480 
3481 	rc = register_pernet_subsys(&smc_net_ops);
3482 	if (rc)
3483 		return rc;
3484 
3485 	rc = register_pernet_subsys(&smc_net_stat_ops);
3486 	if (rc)
3487 		goto out_pernet_subsys;
3488 
3489 	rc = smc_ism_init();
3490 	if (rc)
3491 		goto out_pernet_subsys_stat;
3492 	smc_clc_init();
3493 
3494 	rc = smc_nl_init();
3495 	if (rc)
3496 		goto out_ism;
3497 
3498 	rc = smc_pnet_init();
3499 	if (rc)
3500 		goto out_nl;
3501 
3502 	rc = -ENOMEM;
3503 
3504 	smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3505 	if (!smc_tcp_ls_wq)
3506 		goto out_pnet;
3507 
3508 	smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3509 	if (!smc_hs_wq)
3510 		goto out_alloc_tcp_ls_wq;
3511 
3512 	smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3513 	if (!smc_close_wq)
3514 		goto out_alloc_hs_wq;
3515 
3516 	rc = smc_core_init();
3517 	if (rc) {
3518 		pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3519 		goto out_alloc_wqs;
3520 	}
3521 
3522 	rc = smc_llc_init();
3523 	if (rc) {
3524 		pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3525 		goto out_core;
3526 	}
3527 
3528 	rc = smc_cdc_init();
3529 	if (rc) {
3530 		pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3531 		goto out_core;
3532 	}
3533 
3534 	rc = proto_register(&smc_proto, 1);
3535 	if (rc) {
3536 		pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3537 		goto out_core;
3538 	}
3539 
3540 	rc = proto_register(&smc_proto6, 1);
3541 	if (rc) {
3542 		pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3543 		goto out_proto;
3544 	}
3545 
3546 	rc = sock_register(&smc_sock_family_ops);
3547 	if (rc) {
3548 		pr_err("%s: sock_register fails with %d\n", __func__, rc);
3549 		goto out_proto6;
3550 	}
3551 	INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3552 	INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3553 
3554 	rc = smc_ib_register_client();
3555 	if (rc) {
3556 		pr_err("%s: ib_register fails with %d\n", __func__, rc);
3557 		goto out_sock;
3558 	}
3559 
3560 	rc = tcp_register_ulp(&smc_ulp_ops);
3561 	if (rc) {
3562 		pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3563 		goto out_ib;
3564 	}
3565 
3566 	static_branch_enable(&tcp_have_smc);
3567 	return 0;
3568 
3569 out_ib:
3570 	smc_ib_unregister_client();
3571 out_sock:
3572 	sock_unregister(PF_SMC);
3573 out_proto6:
3574 	proto_unregister(&smc_proto6);
3575 out_proto:
3576 	proto_unregister(&smc_proto);
3577 out_core:
3578 	smc_core_exit();
3579 out_alloc_wqs:
3580 	destroy_workqueue(smc_close_wq);
3581 out_alloc_hs_wq:
3582 	destroy_workqueue(smc_hs_wq);
3583 out_alloc_tcp_ls_wq:
3584 	destroy_workqueue(smc_tcp_ls_wq);
3585 out_pnet:
3586 	smc_pnet_exit();
3587 out_nl:
3588 	smc_nl_exit();
3589 out_ism:
3590 	smc_clc_exit();
3591 	smc_ism_exit();
3592 out_pernet_subsys_stat:
3593 	unregister_pernet_subsys(&smc_net_stat_ops);
3594 out_pernet_subsys:
3595 	unregister_pernet_subsys(&smc_net_ops);
3596 
3597 	return rc;
3598 }
3599 
3600 static void __exit smc_exit(void)
3601 {
3602 	static_branch_disable(&tcp_have_smc);
3603 	tcp_unregister_ulp(&smc_ulp_ops);
3604 	sock_unregister(PF_SMC);
3605 	smc_core_exit();
3606 	smc_ib_unregister_client();
3607 	smc_ism_exit();
3608 	destroy_workqueue(smc_close_wq);
3609 	destroy_workqueue(smc_tcp_ls_wq);
3610 	destroy_workqueue(smc_hs_wq);
3611 	proto_unregister(&smc_proto6);
3612 	proto_unregister(&smc_proto);
3613 	smc_pnet_exit();
3614 	smc_nl_exit();
3615 	smc_clc_exit();
3616 	unregister_pernet_subsys(&smc_net_stat_ops);
3617 	unregister_pernet_subsys(&smc_net_ops);
3618 	rcu_barrier();
3619 }
3620 
3621 module_init(smc_init);
3622 module_exit(smc_exit);
3623 
3624 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3625 MODULE_DESCRIPTION("smc socket address family");
3626 MODULE_LICENSE("GPL");
3627 MODULE_ALIAS_NETPROTO(PF_SMC);
3628 MODULE_ALIAS_TCP_ULP("smc");
3629 MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);
3630