xref: /linux/net/smc/af_smc.c (revision da923feefead2efc05ef21eb2a3f1058fe4c13ae)
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 		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 = 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 	qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
603 			      SMC_LLC_CONFIRM_LINK);
604 	if (!qentry) {
605 		struct smc_clc_msg_decline dclc;
606 
607 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
608 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
609 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
610 	}
611 	smc_llc_save_peer_uid(qentry);
612 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
613 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
614 	if (rc)
615 		return SMC_CLC_DECL_RMBE_EC;
616 
617 	rc = smc_ib_modify_qp_rts(link);
618 	if (rc)
619 		return SMC_CLC_DECL_ERR_RDYLNK;
620 
621 	smc_wr_remember_qp_attr(link);
622 
623 	/* reg the sndbuf if it was vzalloced */
624 	if (smc->conn.sndbuf_desc->is_vm) {
625 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
626 			return SMC_CLC_DECL_ERR_REGBUF;
627 	}
628 
629 	/* reg the rmb */
630 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
631 		return SMC_CLC_DECL_ERR_REGBUF;
632 
633 	/* confirm_rkey is implicit on 1st contact */
634 	smc->conn.rmb_desc->is_conf_rkey = true;
635 
636 	/* send CONFIRM LINK response over RoCE fabric */
637 	rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
638 	if (rc < 0)
639 		return SMC_CLC_DECL_TIMEOUT_CL;
640 
641 	smc_llc_link_active(link);
642 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
643 
644 	if (link->lgr->max_links > 1) {
645 		/* optional 2nd link, receive ADD LINK request from server */
646 		qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
647 				      SMC_LLC_ADD_LINK);
648 		if (!qentry) {
649 			struct smc_clc_msg_decline dclc;
650 
651 			rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
652 					      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
653 			if (rc == -EAGAIN)
654 				rc = 0; /* no DECLINE received, go with one link */
655 			return rc;
656 		}
657 		smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
658 		smc_llc_cli_add_link(link, qentry);
659 	}
660 	return 0;
661 }
662 
663 static bool smc_isascii(char *hostname)
664 {
665 	int i;
666 
667 	for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
668 		if (!isascii(hostname[i]))
669 			return false;
670 	return true;
671 }
672 
673 static void smc_conn_save_peer_info_fce(struct smc_sock *smc,
674 					struct smc_clc_msg_accept_confirm *clc)
675 {
676 	struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
677 		(struct smc_clc_msg_accept_confirm_v2 *)clc;
678 	struct smc_clc_first_contact_ext *fce;
679 	int clc_v2_len;
680 
681 	if (clc->hdr.version == SMC_V1 ||
682 	    !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
683 		return;
684 
685 	if (smc->conn.lgr->is_smcd) {
686 		memcpy(smc->conn.lgr->negotiated_eid, clc_v2->d1.eid,
687 		       SMC_MAX_EID_LEN);
688 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
689 					 d1);
690 	} else {
691 		memcpy(smc->conn.lgr->negotiated_eid, clc_v2->r1.eid,
692 		       SMC_MAX_EID_LEN);
693 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
694 					 r1);
695 	}
696 	fce = (struct smc_clc_first_contact_ext *)(((u8 *)clc_v2) + 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 = clc->d0.token;
723 	/* msg header takes up space in the buffer */
724 	smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
725 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
726 	smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
727 }
728 
729 static void smc_conn_save_peer_info(struct smc_sock *smc,
730 				    struct smc_clc_msg_accept_confirm *clc)
731 {
732 	if (smc->conn.lgr->is_smcd)
733 		smcd_conn_save_peer_info(smc, clc);
734 	else
735 		smcr_conn_save_peer_info(smc, clc);
736 	smc_conn_save_peer_info_fce(smc, clc);
737 }
738 
739 static void smc_link_save_peer_info(struct smc_link *link,
740 				    struct smc_clc_msg_accept_confirm *clc,
741 				    struct smc_init_info *ini)
742 {
743 	link->peer_qpn = ntoh24(clc->r0.qpn);
744 	memcpy(link->peer_gid, ini->peer_gid, SMC_GID_SIZE);
745 	memcpy(link->peer_mac, ini->peer_mac, sizeof(link->peer_mac));
746 	link->peer_psn = ntoh24(clc->r0.psn);
747 	link->peer_mtu = clc->r0.qp_mtu;
748 }
749 
750 static void smc_stat_inc_fback_rsn_cnt(struct smc_sock *smc,
751 				       struct smc_stats_fback *fback_arr)
752 {
753 	int cnt;
754 
755 	for (cnt = 0; cnt < SMC_MAX_FBACK_RSN_CNT; cnt++) {
756 		if (fback_arr[cnt].fback_code == smc->fallback_rsn) {
757 			fback_arr[cnt].count++;
758 			break;
759 		}
760 		if (!fback_arr[cnt].fback_code) {
761 			fback_arr[cnt].fback_code = smc->fallback_rsn;
762 			fback_arr[cnt].count++;
763 			break;
764 		}
765 	}
766 }
767 
768 static void smc_stat_fallback(struct smc_sock *smc)
769 {
770 	struct net *net = sock_net(&smc->sk);
771 
772 	mutex_lock(&net->smc.mutex_fback_rsn);
773 	if (smc->listen_smc) {
774 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->srv);
775 		net->smc.fback_rsn->srv_fback_cnt++;
776 	} else {
777 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->clnt);
778 		net->smc.fback_rsn->clnt_fback_cnt++;
779 	}
780 	mutex_unlock(&net->smc.mutex_fback_rsn);
781 }
782 
783 /* must be called under rcu read lock */
784 static void smc_fback_wakeup_waitqueue(struct smc_sock *smc, void *key)
785 {
786 	struct socket_wq *wq;
787 	__poll_t flags;
788 
789 	wq = rcu_dereference(smc->sk.sk_wq);
790 	if (!skwq_has_sleeper(wq))
791 		return;
792 
793 	/* wake up smc sk->sk_wq */
794 	if (!key) {
795 		/* sk_state_change */
796 		wake_up_interruptible_all(&wq->wait);
797 	} else {
798 		flags = key_to_poll(key);
799 		if (flags & (EPOLLIN | EPOLLOUT))
800 			/* sk_data_ready or sk_write_space */
801 			wake_up_interruptible_sync_poll(&wq->wait, flags);
802 		else if (flags & EPOLLERR)
803 			/* sk_error_report */
804 			wake_up_interruptible_poll(&wq->wait, flags);
805 	}
806 }
807 
808 static int smc_fback_mark_woken(wait_queue_entry_t *wait,
809 				unsigned int mode, int sync, void *key)
810 {
811 	struct smc_mark_woken *mark =
812 		container_of(wait, struct smc_mark_woken, wait_entry);
813 
814 	mark->woken = true;
815 	mark->key = key;
816 	return 0;
817 }
818 
819 static void smc_fback_forward_wakeup(struct smc_sock *smc, struct sock *clcsk,
820 				     void (*clcsock_callback)(struct sock *sk))
821 {
822 	struct smc_mark_woken mark = { .woken = false };
823 	struct socket_wq *wq;
824 
825 	init_waitqueue_func_entry(&mark.wait_entry,
826 				  smc_fback_mark_woken);
827 	rcu_read_lock();
828 	wq = rcu_dereference(clcsk->sk_wq);
829 	if (!wq)
830 		goto out;
831 	add_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
832 	clcsock_callback(clcsk);
833 	remove_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
834 
835 	if (mark.woken)
836 		smc_fback_wakeup_waitqueue(smc, mark.key);
837 out:
838 	rcu_read_unlock();
839 }
840 
841 static void smc_fback_state_change(struct sock *clcsk)
842 {
843 	struct smc_sock *smc;
844 
845 	read_lock_bh(&clcsk->sk_callback_lock);
846 	smc = smc_clcsock_user_data(clcsk);
847 	if (smc)
848 		smc_fback_forward_wakeup(smc, clcsk,
849 					 smc->clcsk_state_change);
850 	read_unlock_bh(&clcsk->sk_callback_lock);
851 }
852 
853 static void smc_fback_data_ready(struct sock *clcsk)
854 {
855 	struct smc_sock *smc;
856 
857 	read_lock_bh(&clcsk->sk_callback_lock);
858 	smc = smc_clcsock_user_data(clcsk);
859 	if (smc)
860 		smc_fback_forward_wakeup(smc, clcsk,
861 					 smc->clcsk_data_ready);
862 	read_unlock_bh(&clcsk->sk_callback_lock);
863 }
864 
865 static void smc_fback_write_space(struct sock *clcsk)
866 {
867 	struct smc_sock *smc;
868 
869 	read_lock_bh(&clcsk->sk_callback_lock);
870 	smc = smc_clcsock_user_data(clcsk);
871 	if (smc)
872 		smc_fback_forward_wakeup(smc, clcsk,
873 					 smc->clcsk_write_space);
874 	read_unlock_bh(&clcsk->sk_callback_lock);
875 }
876 
877 static void smc_fback_error_report(struct sock *clcsk)
878 {
879 	struct smc_sock *smc;
880 
881 	read_lock_bh(&clcsk->sk_callback_lock);
882 	smc = smc_clcsock_user_data(clcsk);
883 	if (smc)
884 		smc_fback_forward_wakeup(smc, clcsk,
885 					 smc->clcsk_error_report);
886 	read_unlock_bh(&clcsk->sk_callback_lock);
887 }
888 
889 static void smc_fback_replace_callbacks(struct smc_sock *smc)
890 {
891 	struct sock *clcsk = smc->clcsock->sk;
892 
893 	write_lock_bh(&clcsk->sk_callback_lock);
894 	clcsk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
895 
896 	smc_clcsock_replace_cb(&clcsk->sk_state_change, smc_fback_state_change,
897 			       &smc->clcsk_state_change);
898 	smc_clcsock_replace_cb(&clcsk->sk_data_ready, smc_fback_data_ready,
899 			       &smc->clcsk_data_ready);
900 	smc_clcsock_replace_cb(&clcsk->sk_write_space, smc_fback_write_space,
901 			       &smc->clcsk_write_space);
902 	smc_clcsock_replace_cb(&clcsk->sk_error_report, smc_fback_error_report,
903 			       &smc->clcsk_error_report);
904 
905 	write_unlock_bh(&clcsk->sk_callback_lock);
906 }
907 
908 static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code)
909 {
910 	int rc = 0;
911 
912 	mutex_lock(&smc->clcsock_release_lock);
913 	if (!smc->clcsock) {
914 		rc = -EBADF;
915 		goto out;
916 	}
917 
918 	smc->use_fallback = true;
919 	smc->fallback_rsn = reason_code;
920 	smc_stat_fallback(smc);
921 	trace_smc_switch_to_fallback(smc, reason_code);
922 	if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
923 		smc->clcsock->file = smc->sk.sk_socket->file;
924 		smc->clcsock->file->private_data = smc->clcsock;
925 		smc->clcsock->wq.fasync_list =
926 			smc->sk.sk_socket->wq.fasync_list;
927 
928 		/* There might be some wait entries remaining
929 		 * in smc sk->sk_wq and they should be woken up
930 		 * as clcsock's wait queue is woken up.
931 		 */
932 		smc_fback_replace_callbacks(smc);
933 	}
934 out:
935 	mutex_unlock(&smc->clcsock_release_lock);
936 	return rc;
937 }
938 
939 /* fall back during connect */
940 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
941 {
942 	struct net *net = sock_net(&smc->sk);
943 	int rc = 0;
944 
945 	rc = smc_switch_to_fallback(smc, reason_code);
946 	if (rc) { /* fallback fails */
947 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
948 		if (smc->sk.sk_state == SMC_INIT)
949 			sock_put(&smc->sk); /* passive closing */
950 		return rc;
951 	}
952 	smc_copy_sock_settings_to_clc(smc);
953 	smc->connect_nonblock = 0;
954 	if (smc->sk.sk_state == SMC_INIT)
955 		smc->sk.sk_state = SMC_ACTIVE;
956 	return 0;
957 }
958 
959 /* decline and fall back during connect */
960 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
961 					u8 version)
962 {
963 	struct net *net = sock_net(&smc->sk);
964 	int rc;
965 
966 	if (reason_code < 0) { /* error, fallback is not possible */
967 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
968 		if (smc->sk.sk_state == SMC_INIT)
969 			sock_put(&smc->sk); /* passive closing */
970 		return reason_code;
971 	}
972 	if (reason_code != SMC_CLC_DECL_PEERDECL) {
973 		rc = smc_clc_send_decline(smc, reason_code, version);
974 		if (rc < 0) {
975 			this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
976 			if (smc->sk.sk_state == SMC_INIT)
977 				sock_put(&smc->sk); /* passive closing */
978 			return rc;
979 		}
980 	}
981 	return smc_connect_fallback(smc, reason_code);
982 }
983 
984 static void smc_conn_abort(struct smc_sock *smc, int local_first)
985 {
986 	struct smc_connection *conn = &smc->conn;
987 	struct smc_link_group *lgr = conn->lgr;
988 	bool lgr_valid = false;
989 
990 	if (smc_conn_lgr_valid(conn))
991 		lgr_valid = true;
992 
993 	smc_conn_free(conn);
994 	if (local_first && lgr_valid)
995 		smc_lgr_cleanup_early(lgr);
996 }
997 
998 /* check if there is a rdma device available for this connection. */
999 /* called for connect and listen */
1000 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
1001 {
1002 	/* PNET table look up: search active ib_device and port
1003 	 * within same PNETID that also contains the ethernet device
1004 	 * used for the internal TCP socket
1005 	 */
1006 	smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
1007 	if (!ini->check_smcrv2 && !ini->ib_dev)
1008 		return SMC_CLC_DECL_NOSMCRDEV;
1009 	if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
1010 		return SMC_CLC_DECL_NOSMCRDEV;
1011 	return 0;
1012 }
1013 
1014 /* check if there is an ISM device available for this connection. */
1015 /* called for connect and listen */
1016 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
1017 {
1018 	/* Find ISM device with same PNETID as connecting interface  */
1019 	smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
1020 	if (!ini->ism_dev[0])
1021 		return SMC_CLC_DECL_NOSMCDDEV;
1022 	else
1023 		ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
1024 	return 0;
1025 }
1026 
1027 /* is chid unique for the ism devices that are already determined? */
1028 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
1029 					   int cnt)
1030 {
1031 	int i = (!ini->ism_dev[0]) ? 1 : 0;
1032 
1033 	for (; i < cnt; i++)
1034 		if (ini->ism_chid[i] == chid)
1035 			return false;
1036 	return true;
1037 }
1038 
1039 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
1040  * PNETID matching net_device)
1041  */
1042 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
1043 				       struct smc_init_info *ini)
1044 {
1045 	int rc = SMC_CLC_DECL_NOSMCDDEV;
1046 	struct smcd_dev *smcd;
1047 	int i = 1;
1048 	u16 chid;
1049 
1050 	if (smcd_indicated(ini->smc_type_v1))
1051 		rc = 0;		/* already initialized for V1 */
1052 	mutex_lock(&smcd_dev_list.mutex);
1053 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1054 		if (smcd->going_away || smcd == ini->ism_dev[0])
1055 			continue;
1056 		chid = smc_ism_get_chid(smcd);
1057 		if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
1058 			continue;
1059 		if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
1060 		    smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
1061 			ini->ism_dev[i] = smcd;
1062 			ini->ism_chid[i] = chid;
1063 			ini->is_smcd = true;
1064 			rc = 0;
1065 			i++;
1066 			if (i > SMC_MAX_ISM_DEVS)
1067 				break;
1068 		}
1069 	}
1070 	mutex_unlock(&smcd_dev_list.mutex);
1071 	ini->ism_offered_cnt = i - 1;
1072 	if (!ini->ism_dev[0] && !ini->ism_dev[1])
1073 		ini->smcd_version = 0;
1074 
1075 	return rc;
1076 }
1077 
1078 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
1079 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
1080 				      struct smc_init_info *ini)
1081 {
1082 	if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
1083 		return SMC_CLC_DECL_ISMVLANERR;
1084 	return 0;
1085 }
1086 
1087 static int smc_find_proposal_devices(struct smc_sock *smc,
1088 				     struct smc_init_info *ini)
1089 {
1090 	int rc = 0;
1091 
1092 	/* check if there is an ism device available */
1093 	if (!(ini->smcd_version & SMC_V1) ||
1094 	    smc_find_ism_device(smc, ini) ||
1095 	    smc_connect_ism_vlan_setup(smc, ini))
1096 		ini->smcd_version &= ~SMC_V1;
1097 	/* else ISM V1 is supported for this connection */
1098 
1099 	/* check if there is an rdma device available */
1100 	if (!(ini->smcr_version & SMC_V1) ||
1101 	    smc_find_rdma_device(smc, ini))
1102 		ini->smcr_version &= ~SMC_V1;
1103 	/* else RDMA is supported for this connection */
1104 
1105 	ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
1106 					      ini->smcr_version & SMC_V1);
1107 
1108 	/* check if there is an ism v2 device available */
1109 	if (!(ini->smcd_version & SMC_V2) ||
1110 	    !smc_ism_is_v2_capable() ||
1111 	    smc_find_ism_v2_device_clnt(smc, ini))
1112 		ini->smcd_version &= ~SMC_V2;
1113 
1114 	/* check if there is an rdma v2 device available */
1115 	ini->check_smcrv2 = true;
1116 	ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
1117 	if (!(ini->smcr_version & SMC_V2) ||
1118 	    smc->clcsock->sk->sk_family != AF_INET ||
1119 	    !smc_clc_ueid_count() ||
1120 	    smc_find_rdma_device(smc, ini))
1121 		ini->smcr_version &= ~SMC_V2;
1122 	ini->check_smcrv2 = false;
1123 
1124 	ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
1125 					      ini->smcr_version & SMC_V2);
1126 
1127 	/* if neither ISM nor RDMA are supported, fallback */
1128 	if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
1129 		rc = SMC_CLC_DECL_NOSMCDEV;
1130 
1131 	return rc;
1132 }
1133 
1134 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
1135  * used, the VLAN ID will be registered again during the connection setup.
1136  */
1137 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
1138 					struct smc_init_info *ini)
1139 {
1140 	if (!smcd_indicated(ini->smc_type_v1))
1141 		return 0;
1142 	if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
1143 		return SMC_CLC_DECL_CNFERR;
1144 	return 0;
1145 }
1146 
1147 #define SMC_CLC_MAX_ACCEPT_LEN \
1148 	(sizeof(struct smc_clc_msg_accept_confirm_v2) + \
1149 	 sizeof(struct smc_clc_first_contact_ext_v2x) + \
1150 	 sizeof(struct smc_clc_msg_trail))
1151 
1152 /* CLC handshake during connect */
1153 static int smc_connect_clc(struct smc_sock *smc,
1154 			   struct smc_clc_msg_accept_confirm_v2 *aclc2,
1155 			   struct smc_init_info *ini)
1156 {
1157 	int rc = 0;
1158 
1159 	/* do inband token exchange */
1160 	rc = smc_clc_send_proposal(smc, ini);
1161 	if (rc)
1162 		return rc;
1163 	/* receive SMC Accept CLC message */
1164 	return smc_clc_wait_msg(smc, aclc2, SMC_CLC_MAX_ACCEPT_LEN,
1165 				SMC_CLC_ACCEPT, CLC_WAIT_TIME);
1166 }
1167 
1168 void smc_fill_gid_list(struct smc_link_group *lgr,
1169 		       struct smc_gidlist *gidlist,
1170 		       struct smc_ib_device *known_dev, u8 *known_gid)
1171 {
1172 	struct smc_init_info *alt_ini = NULL;
1173 
1174 	memset(gidlist, 0, sizeof(*gidlist));
1175 	memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
1176 
1177 	alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
1178 	if (!alt_ini)
1179 		goto out;
1180 
1181 	alt_ini->vlan_id = lgr->vlan_id;
1182 	alt_ini->check_smcrv2 = true;
1183 	alt_ini->smcrv2.saddr = lgr->saddr;
1184 	smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
1185 
1186 	if (!alt_ini->smcrv2.ib_dev_v2)
1187 		goto out;
1188 
1189 	memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
1190 	       SMC_GID_SIZE);
1191 
1192 out:
1193 	kfree(alt_ini);
1194 }
1195 
1196 static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
1197 				       struct smc_clc_msg_accept_confirm *aclc,
1198 				       struct smc_init_info *ini)
1199 {
1200 	struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1201 		(struct smc_clc_msg_accept_confirm_v2 *)aclc;
1202 	struct smc_clc_first_contact_ext *fce =
1203 		smc_get_clc_first_contact_ext(clc_v2, false);
1204 	int rc;
1205 
1206 	if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1207 		return 0;
1208 
1209 	if (fce->v2_direct) {
1210 		memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1211 		ini->smcrv2.uses_gateway = false;
1212 	} else {
1213 		if (smc_ib_find_route(smc->clcsock->sk->sk_rcv_saddr,
1214 				      smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1215 				      ini->smcrv2.nexthop_mac,
1216 				      &ini->smcrv2.uses_gateway))
1217 			return SMC_CLC_DECL_NOROUTE;
1218 		if (!ini->smcrv2.uses_gateway) {
1219 			/* mismatch: peer claims indirect, but its direct */
1220 			return SMC_CLC_DECL_NOINDIRECT;
1221 		}
1222 	}
1223 
1224 	ini->release_nr = fce->release;
1225 	rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1226 	if (rc)
1227 		return rc;
1228 
1229 	return 0;
1230 }
1231 
1232 /* setup for RDMA connection of client */
1233 static int smc_connect_rdma(struct smc_sock *smc,
1234 			    struct smc_clc_msg_accept_confirm *aclc,
1235 			    struct smc_init_info *ini)
1236 {
1237 	int i, reason_code = 0;
1238 	struct smc_link *link;
1239 	u8 *eid = NULL;
1240 
1241 	ini->is_smcd = false;
1242 	ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1243 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1244 	memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1245 	memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1246 	memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1247 	ini->max_conns = SMC_CONN_PER_LGR_MAX;
1248 	ini->max_links = SMC_LINKS_ADD_LNK_MAX;
1249 
1250 	reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1251 	if (reason_code)
1252 		return reason_code;
1253 
1254 	mutex_lock(&smc_client_lgr_pending);
1255 	reason_code = smc_conn_create(smc, ini);
1256 	if (reason_code) {
1257 		mutex_unlock(&smc_client_lgr_pending);
1258 		return reason_code;
1259 	}
1260 
1261 	smc_conn_save_peer_info(smc, aclc);
1262 
1263 	if (ini->first_contact_local) {
1264 		link = smc->conn.lnk;
1265 	} else {
1266 		/* set link that was assigned by server */
1267 		link = NULL;
1268 		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1269 			struct smc_link *l = &smc->conn.lgr->lnk[i];
1270 
1271 			if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1272 			    !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1273 				    SMC_GID_SIZE) &&
1274 			    (aclc->hdr.version > SMC_V1 ||
1275 			     !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1276 				     sizeof(l->peer_mac)))) {
1277 				link = l;
1278 				break;
1279 			}
1280 		}
1281 		if (!link) {
1282 			reason_code = SMC_CLC_DECL_NOSRVLINK;
1283 			goto connect_abort;
1284 		}
1285 		smc_switch_link_and_count(&smc->conn, link);
1286 	}
1287 
1288 	/* create send buffer and rmb */
1289 	if (smc_buf_create(smc, false)) {
1290 		reason_code = SMC_CLC_DECL_MEM;
1291 		goto connect_abort;
1292 	}
1293 
1294 	if (ini->first_contact_local)
1295 		smc_link_save_peer_info(link, aclc, ini);
1296 
1297 	if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1298 		reason_code = SMC_CLC_DECL_ERR_RTOK;
1299 		goto connect_abort;
1300 	}
1301 
1302 	smc_close_init(smc);
1303 	smc_rx_init(smc);
1304 
1305 	if (ini->first_contact_local) {
1306 		if (smc_ib_ready_link(link)) {
1307 			reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1308 			goto connect_abort;
1309 		}
1310 	} else {
1311 		/* reg sendbufs if they were vzalloced */
1312 		if (smc->conn.sndbuf_desc->is_vm) {
1313 			if (smcr_lgr_reg_sndbufs(link, smc->conn.sndbuf_desc)) {
1314 				reason_code = SMC_CLC_DECL_ERR_REGBUF;
1315 				goto connect_abort;
1316 			}
1317 		}
1318 		if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1319 			reason_code = SMC_CLC_DECL_ERR_REGBUF;
1320 			goto connect_abort;
1321 		}
1322 	}
1323 
1324 	if (aclc->hdr.version > SMC_V1) {
1325 		struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1326 			(struct smc_clc_msg_accept_confirm_v2 *)aclc;
1327 
1328 		eid = clc_v2->r1.eid;
1329 		if (ini->first_contact_local)
1330 			smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1331 					  link->smcibdev, link->gid);
1332 	}
1333 
1334 	reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1335 					   aclc->hdr.version, eid, ini);
1336 	if (reason_code)
1337 		goto connect_abort;
1338 
1339 	smc_tx_init(smc);
1340 
1341 	if (ini->first_contact_local) {
1342 		/* QP confirmation over RoCE fabric */
1343 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1344 		reason_code = smcr_clnt_conf_first_link(smc);
1345 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1346 		if (reason_code)
1347 			goto connect_abort;
1348 	}
1349 	mutex_unlock(&smc_client_lgr_pending);
1350 
1351 	smc_copy_sock_settings_to_clc(smc);
1352 	smc->connect_nonblock = 0;
1353 	if (smc->sk.sk_state == SMC_INIT)
1354 		smc->sk.sk_state = SMC_ACTIVE;
1355 
1356 	return 0;
1357 connect_abort:
1358 	smc_conn_abort(smc, ini->first_contact_local);
1359 	mutex_unlock(&smc_client_lgr_pending);
1360 	smc->connect_nonblock = 0;
1361 
1362 	return reason_code;
1363 }
1364 
1365 /* The server has chosen one of the proposed ISM devices for the communication.
1366  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1367  */
1368 static int
1369 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm_v2 *aclc,
1370 			       struct smc_init_info *ini)
1371 {
1372 	int i;
1373 
1374 	for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1375 		if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1376 			ini->ism_selected = i;
1377 			return 0;
1378 		}
1379 	}
1380 
1381 	return -EPROTO;
1382 }
1383 
1384 /* setup for ISM connection of client */
1385 static int smc_connect_ism(struct smc_sock *smc,
1386 			   struct smc_clc_msg_accept_confirm *aclc,
1387 			   struct smc_init_info *ini)
1388 {
1389 	u8 *eid = NULL;
1390 	int rc = 0;
1391 
1392 	ini->is_smcd = true;
1393 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1394 
1395 	if (aclc->hdr.version == SMC_V2) {
1396 		struct smc_clc_msg_accept_confirm_v2 *aclc_v2 =
1397 			(struct smc_clc_msg_accept_confirm_v2 *)aclc;
1398 
1399 		if (ini->first_contact_peer) {
1400 			struct smc_clc_first_contact_ext *fce =
1401 				smc_get_clc_first_contact_ext(aclc_v2, true);
1402 
1403 			ini->release_nr = fce->release;
1404 			rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1405 			if (rc)
1406 				return rc;
1407 		}
1408 
1409 		rc = smc_v2_determine_accepted_chid(aclc_v2, ini);
1410 		if (rc)
1411 			return rc;
1412 	}
1413 	ini->ism_peer_gid[ini->ism_selected] = aclc->d0.gid;
1414 
1415 	/* there is only one lgr role for SMC-D; use server lock */
1416 	mutex_lock(&smc_server_lgr_pending);
1417 	rc = smc_conn_create(smc, ini);
1418 	if (rc) {
1419 		mutex_unlock(&smc_server_lgr_pending);
1420 		return rc;
1421 	}
1422 
1423 	/* Create send and receive buffers */
1424 	rc = smc_buf_create(smc, true);
1425 	if (rc) {
1426 		rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1427 		goto connect_abort;
1428 	}
1429 
1430 	smc_conn_save_peer_info(smc, aclc);
1431 	smc_close_init(smc);
1432 	smc_rx_init(smc);
1433 	smc_tx_init(smc);
1434 
1435 	if (aclc->hdr.version > SMC_V1) {
1436 		struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1437 			(struct smc_clc_msg_accept_confirm_v2 *)aclc;
1438 
1439 		eid = clc_v2->d1.eid;
1440 	}
1441 
1442 	rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1443 				  aclc->hdr.version, eid, ini);
1444 	if (rc)
1445 		goto connect_abort;
1446 	mutex_unlock(&smc_server_lgr_pending);
1447 
1448 	smc_copy_sock_settings_to_clc(smc);
1449 	smc->connect_nonblock = 0;
1450 	if (smc->sk.sk_state == SMC_INIT)
1451 		smc->sk.sk_state = SMC_ACTIVE;
1452 
1453 	return 0;
1454 connect_abort:
1455 	smc_conn_abort(smc, ini->first_contact_local);
1456 	mutex_unlock(&smc_server_lgr_pending);
1457 	smc->connect_nonblock = 0;
1458 
1459 	return rc;
1460 }
1461 
1462 /* check if received accept type and version matches a proposed one */
1463 static int smc_connect_check_aclc(struct smc_init_info *ini,
1464 				  struct smc_clc_msg_accept_confirm *aclc)
1465 {
1466 	if (aclc->hdr.typev1 != SMC_TYPE_R &&
1467 	    aclc->hdr.typev1 != SMC_TYPE_D)
1468 		return SMC_CLC_DECL_MODEUNSUPP;
1469 
1470 	if (aclc->hdr.version >= SMC_V2) {
1471 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1472 		     !smcr_indicated(ini->smc_type_v2)) ||
1473 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1474 		     !smcd_indicated(ini->smc_type_v2)))
1475 			return SMC_CLC_DECL_MODEUNSUPP;
1476 	} else {
1477 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1478 		     !smcr_indicated(ini->smc_type_v1)) ||
1479 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1480 		     !smcd_indicated(ini->smc_type_v1)))
1481 			return SMC_CLC_DECL_MODEUNSUPP;
1482 	}
1483 
1484 	return 0;
1485 }
1486 
1487 /* perform steps before actually connecting */
1488 static int __smc_connect(struct smc_sock *smc)
1489 {
1490 	u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1491 	struct smc_clc_msg_accept_confirm_v2 *aclc2;
1492 	struct smc_clc_msg_accept_confirm *aclc;
1493 	struct smc_init_info *ini = NULL;
1494 	u8 *buf = NULL;
1495 	int rc = 0;
1496 
1497 	if (smc->use_fallback)
1498 		return smc_connect_fallback(smc, smc->fallback_rsn);
1499 
1500 	/* if peer has not signalled SMC-capability, fall back */
1501 	if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1502 		return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1503 
1504 	/* IPSec connections opt out of SMC optimizations */
1505 	if (using_ipsec(smc))
1506 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1507 						    version);
1508 
1509 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1510 	if (!ini)
1511 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1512 						    version);
1513 
1514 	ini->smcd_version = SMC_V1 | SMC_V2;
1515 	ini->smcr_version = SMC_V1 | SMC_V2;
1516 	ini->smc_type_v1 = SMC_TYPE_B;
1517 	ini->smc_type_v2 = SMC_TYPE_B;
1518 
1519 	/* get vlan id from IP device */
1520 	if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1521 		ini->smcd_version &= ~SMC_V1;
1522 		ini->smcr_version = 0;
1523 		ini->smc_type_v1 = SMC_TYPE_N;
1524 		if (!ini->smcd_version) {
1525 			rc = SMC_CLC_DECL_GETVLANERR;
1526 			goto fallback;
1527 		}
1528 	}
1529 
1530 	rc = smc_find_proposal_devices(smc, ini);
1531 	if (rc)
1532 		goto fallback;
1533 
1534 	buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1535 	if (!buf) {
1536 		rc = SMC_CLC_DECL_MEM;
1537 		goto fallback;
1538 	}
1539 	aclc2 = (struct smc_clc_msg_accept_confirm_v2 *)buf;
1540 	aclc = (struct smc_clc_msg_accept_confirm *)aclc2;
1541 
1542 	/* perform CLC handshake */
1543 	rc = smc_connect_clc(smc, aclc2, ini);
1544 	if (rc) {
1545 		/* -EAGAIN on timeout, see tcp_recvmsg() */
1546 		if (rc == -EAGAIN) {
1547 			rc = -ETIMEDOUT;
1548 			smc->sk.sk_err = ETIMEDOUT;
1549 		}
1550 		goto vlan_cleanup;
1551 	}
1552 
1553 	/* check if smc modes and versions of CLC proposal and accept match */
1554 	rc = smc_connect_check_aclc(ini, aclc);
1555 	version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1556 	if (rc)
1557 		goto vlan_cleanup;
1558 
1559 	/* depending on previous steps, connect using rdma or ism */
1560 	if (aclc->hdr.typev1 == SMC_TYPE_R) {
1561 		ini->smcr_version = version;
1562 		rc = smc_connect_rdma(smc, aclc, ini);
1563 	} else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1564 		ini->smcd_version = version;
1565 		rc = smc_connect_ism(smc, aclc, ini);
1566 	}
1567 	if (rc)
1568 		goto vlan_cleanup;
1569 
1570 	SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1571 	smc_connect_ism_vlan_cleanup(smc, ini);
1572 	kfree(buf);
1573 	kfree(ini);
1574 	return 0;
1575 
1576 vlan_cleanup:
1577 	smc_connect_ism_vlan_cleanup(smc, ini);
1578 	kfree(buf);
1579 fallback:
1580 	kfree(ini);
1581 	return smc_connect_decline_fallback(smc, rc, version);
1582 }
1583 
1584 static void smc_connect_work(struct work_struct *work)
1585 {
1586 	struct smc_sock *smc = container_of(work, struct smc_sock,
1587 					    connect_work);
1588 	long timeo = smc->sk.sk_sndtimeo;
1589 	int rc = 0;
1590 
1591 	if (!timeo)
1592 		timeo = MAX_SCHEDULE_TIMEOUT;
1593 	lock_sock(smc->clcsock->sk);
1594 	if (smc->clcsock->sk->sk_err) {
1595 		smc->sk.sk_err = smc->clcsock->sk->sk_err;
1596 	} else if ((1 << smc->clcsock->sk->sk_state) &
1597 					(TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1598 		rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1599 		if ((rc == -EPIPE) &&
1600 		    ((1 << smc->clcsock->sk->sk_state) &
1601 					(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1602 			rc = 0;
1603 	}
1604 	release_sock(smc->clcsock->sk);
1605 	lock_sock(&smc->sk);
1606 	if (rc != 0 || smc->sk.sk_err) {
1607 		smc->sk.sk_state = SMC_CLOSED;
1608 		if (rc == -EPIPE || rc == -EAGAIN)
1609 			smc->sk.sk_err = EPIPE;
1610 		else if (rc == -ECONNREFUSED)
1611 			smc->sk.sk_err = ECONNREFUSED;
1612 		else if (signal_pending(current))
1613 			smc->sk.sk_err = -sock_intr_errno(timeo);
1614 		sock_put(&smc->sk); /* passive closing */
1615 		goto out;
1616 	}
1617 
1618 	rc = __smc_connect(smc);
1619 	if (rc < 0)
1620 		smc->sk.sk_err = -rc;
1621 
1622 out:
1623 	if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1624 		if (smc->sk.sk_err) {
1625 			smc->sk.sk_state_change(&smc->sk);
1626 		} else { /* allow polling before and after fallback decision */
1627 			smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1628 			smc->sk.sk_write_space(&smc->sk);
1629 		}
1630 	}
1631 	release_sock(&smc->sk);
1632 }
1633 
1634 static int smc_connect(struct socket *sock, struct sockaddr *addr,
1635 		       int alen, int flags)
1636 {
1637 	struct sock *sk = sock->sk;
1638 	struct smc_sock *smc;
1639 	int rc = -EINVAL;
1640 
1641 	smc = smc_sk(sk);
1642 
1643 	/* separate smc parameter checking to be safe */
1644 	if (alen < sizeof(addr->sa_family))
1645 		goto out_err;
1646 	if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1647 		goto out_err;
1648 
1649 	lock_sock(sk);
1650 	switch (sock->state) {
1651 	default:
1652 		rc = -EINVAL;
1653 		goto out;
1654 	case SS_CONNECTED:
1655 		rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1656 		goto out;
1657 	case SS_CONNECTING:
1658 		if (sk->sk_state == SMC_ACTIVE)
1659 			goto connected;
1660 		break;
1661 	case SS_UNCONNECTED:
1662 		sock->state = SS_CONNECTING;
1663 		break;
1664 	}
1665 
1666 	switch (sk->sk_state) {
1667 	default:
1668 		goto out;
1669 	case SMC_CLOSED:
1670 		rc = sock_error(sk) ? : -ECONNABORTED;
1671 		sock->state = SS_UNCONNECTED;
1672 		goto out;
1673 	case SMC_ACTIVE:
1674 		rc = -EISCONN;
1675 		goto out;
1676 	case SMC_INIT:
1677 		break;
1678 	}
1679 
1680 	smc_copy_sock_settings_to_clc(smc);
1681 	tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1682 	if (smc->connect_nonblock) {
1683 		rc = -EALREADY;
1684 		goto out;
1685 	}
1686 	rc = kernel_connect(smc->clcsock, addr, alen, flags);
1687 	if (rc && rc != -EINPROGRESS)
1688 		goto out;
1689 
1690 	if (smc->use_fallback) {
1691 		sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1692 		goto out;
1693 	}
1694 	sock_hold(&smc->sk); /* sock put in passive closing */
1695 	if (flags & O_NONBLOCK) {
1696 		if (queue_work(smc_hs_wq, &smc->connect_work))
1697 			smc->connect_nonblock = 1;
1698 		rc = -EINPROGRESS;
1699 		goto out;
1700 	} else {
1701 		rc = __smc_connect(smc);
1702 		if (rc < 0)
1703 			goto out;
1704 	}
1705 
1706 connected:
1707 	rc = 0;
1708 	sock->state = SS_CONNECTED;
1709 out:
1710 	release_sock(sk);
1711 out_err:
1712 	return rc;
1713 }
1714 
1715 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1716 {
1717 	struct socket *new_clcsock = NULL;
1718 	struct sock *lsk = &lsmc->sk;
1719 	struct sock *new_sk;
1720 	int rc = -EINVAL;
1721 
1722 	release_sock(lsk);
1723 	new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1724 	if (!new_sk) {
1725 		rc = -ENOMEM;
1726 		lsk->sk_err = ENOMEM;
1727 		*new_smc = NULL;
1728 		lock_sock(lsk);
1729 		goto out;
1730 	}
1731 	*new_smc = smc_sk(new_sk);
1732 
1733 	mutex_lock(&lsmc->clcsock_release_lock);
1734 	if (lsmc->clcsock)
1735 		rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1736 	mutex_unlock(&lsmc->clcsock_release_lock);
1737 	lock_sock(lsk);
1738 	if  (rc < 0 && rc != -EAGAIN)
1739 		lsk->sk_err = -rc;
1740 	if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1741 		new_sk->sk_prot->unhash(new_sk);
1742 		if (new_clcsock)
1743 			sock_release(new_clcsock);
1744 		new_sk->sk_state = SMC_CLOSED;
1745 		sock_set_flag(new_sk, SOCK_DEAD);
1746 		sock_put(new_sk); /* final */
1747 		*new_smc = NULL;
1748 		goto out;
1749 	}
1750 
1751 	/* new clcsock has inherited the smc listen-specific sk_data_ready
1752 	 * function; switch it back to the original sk_data_ready function
1753 	 */
1754 	new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1755 
1756 	/* if new clcsock has also inherited the fallback-specific callback
1757 	 * functions, switch them back to the original ones.
1758 	 */
1759 	if (lsmc->use_fallback) {
1760 		if (lsmc->clcsk_state_change)
1761 			new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1762 		if (lsmc->clcsk_write_space)
1763 			new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1764 		if (lsmc->clcsk_error_report)
1765 			new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1766 	}
1767 
1768 	(*new_smc)->clcsock = new_clcsock;
1769 out:
1770 	return rc;
1771 }
1772 
1773 /* add a just created sock to the accept queue of the listen sock as
1774  * candidate for a following socket accept call from user space
1775  */
1776 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1777 {
1778 	struct smc_sock *par = smc_sk(parent);
1779 
1780 	sock_hold(sk); /* sock_put in smc_accept_unlink () */
1781 	spin_lock(&par->accept_q_lock);
1782 	list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1783 	spin_unlock(&par->accept_q_lock);
1784 	sk_acceptq_added(parent);
1785 }
1786 
1787 /* remove a socket from the accept queue of its parental listening socket */
1788 static void smc_accept_unlink(struct sock *sk)
1789 {
1790 	struct smc_sock *par = smc_sk(sk)->listen_smc;
1791 
1792 	spin_lock(&par->accept_q_lock);
1793 	list_del_init(&smc_sk(sk)->accept_q);
1794 	spin_unlock(&par->accept_q_lock);
1795 	sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1796 	sock_put(sk); /* sock_hold in smc_accept_enqueue */
1797 }
1798 
1799 /* remove a sock from the accept queue to bind it to a new socket created
1800  * for a socket accept call from user space
1801  */
1802 struct sock *smc_accept_dequeue(struct sock *parent,
1803 				struct socket *new_sock)
1804 {
1805 	struct smc_sock *isk, *n;
1806 	struct sock *new_sk;
1807 
1808 	list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1809 		new_sk = (struct sock *)isk;
1810 
1811 		smc_accept_unlink(new_sk);
1812 		if (new_sk->sk_state == SMC_CLOSED) {
1813 			new_sk->sk_prot->unhash(new_sk);
1814 			if (isk->clcsock) {
1815 				sock_release(isk->clcsock);
1816 				isk->clcsock = NULL;
1817 			}
1818 			sock_put(new_sk); /* final */
1819 			continue;
1820 		}
1821 		if (new_sock) {
1822 			sock_graft(new_sk, new_sock);
1823 			new_sock->state = SS_CONNECTED;
1824 			if (isk->use_fallback) {
1825 				smc_sk(new_sk)->clcsock->file = new_sock->file;
1826 				isk->clcsock->file->private_data = isk->clcsock;
1827 			}
1828 		}
1829 		return new_sk;
1830 	}
1831 	return NULL;
1832 }
1833 
1834 /* clean up for a created but never accepted sock */
1835 void smc_close_non_accepted(struct sock *sk)
1836 {
1837 	struct smc_sock *smc = smc_sk(sk);
1838 
1839 	sock_hold(sk); /* sock_put below */
1840 	lock_sock(sk);
1841 	if (!sk->sk_lingertime)
1842 		/* wait for peer closing */
1843 		WRITE_ONCE(sk->sk_lingertime, SMC_MAX_STREAM_WAIT_TIMEOUT);
1844 	__smc_release(smc);
1845 	release_sock(sk);
1846 	sock_put(sk); /* sock_hold above */
1847 	sock_put(sk); /* final sock_put */
1848 }
1849 
1850 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1851 {
1852 	struct smc_link *link = smc->conn.lnk;
1853 	struct smc_llc_qentry *qentry;
1854 	int rc;
1855 
1856 	/* reg the sndbuf if it was vzalloced*/
1857 	if (smc->conn.sndbuf_desc->is_vm) {
1858 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
1859 			return SMC_CLC_DECL_ERR_REGBUF;
1860 	}
1861 
1862 	/* reg the rmb */
1863 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
1864 		return SMC_CLC_DECL_ERR_REGBUF;
1865 
1866 	/* send CONFIRM LINK request to client over the RoCE fabric */
1867 	rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1868 	if (rc < 0)
1869 		return SMC_CLC_DECL_TIMEOUT_CL;
1870 
1871 	/* receive CONFIRM LINK response from client over the RoCE fabric */
1872 	qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1873 			      SMC_LLC_CONFIRM_LINK);
1874 	if (!qentry) {
1875 		struct smc_clc_msg_decline dclc;
1876 
1877 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1878 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1879 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1880 	}
1881 	smc_llc_save_peer_uid(qentry);
1882 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1883 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1884 	if (rc)
1885 		return SMC_CLC_DECL_RMBE_EC;
1886 
1887 	/* confirm_rkey is implicit on 1st contact */
1888 	smc->conn.rmb_desc->is_conf_rkey = true;
1889 
1890 	smc_llc_link_active(link);
1891 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1892 
1893 	if (link->lgr->max_links > 1) {
1894 		down_write(&link->lgr->llc_conf_mutex);
1895 		/* initial contact - try to establish second link */
1896 		smc_llc_srv_add_link(link, NULL);
1897 		up_write(&link->lgr->llc_conf_mutex);
1898 	}
1899 	return 0;
1900 }
1901 
1902 /* listen worker: finish */
1903 static void smc_listen_out(struct smc_sock *new_smc)
1904 {
1905 	struct smc_sock *lsmc = new_smc->listen_smc;
1906 	struct sock *newsmcsk = &new_smc->sk;
1907 
1908 	if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1909 		atomic_dec(&lsmc->queued_smc_hs);
1910 
1911 	if (lsmc->sk.sk_state == SMC_LISTEN) {
1912 		lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1913 		smc_accept_enqueue(&lsmc->sk, newsmcsk);
1914 		release_sock(&lsmc->sk);
1915 	} else { /* no longer listening */
1916 		smc_close_non_accepted(newsmcsk);
1917 	}
1918 
1919 	/* Wake up accept */
1920 	lsmc->sk.sk_data_ready(&lsmc->sk);
1921 	sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1922 }
1923 
1924 /* listen worker: finish in state connected */
1925 static void smc_listen_out_connected(struct smc_sock *new_smc)
1926 {
1927 	struct sock *newsmcsk = &new_smc->sk;
1928 
1929 	if (newsmcsk->sk_state == SMC_INIT)
1930 		newsmcsk->sk_state = SMC_ACTIVE;
1931 
1932 	smc_listen_out(new_smc);
1933 }
1934 
1935 /* listen worker: finish in error state */
1936 static void smc_listen_out_err(struct smc_sock *new_smc)
1937 {
1938 	struct sock *newsmcsk = &new_smc->sk;
1939 	struct net *net = sock_net(newsmcsk);
1940 
1941 	this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1942 	if (newsmcsk->sk_state == SMC_INIT)
1943 		sock_put(&new_smc->sk); /* passive closing */
1944 	newsmcsk->sk_state = SMC_CLOSED;
1945 
1946 	smc_listen_out(new_smc);
1947 }
1948 
1949 /* listen worker: decline and fall back if possible */
1950 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1951 			       int local_first, u8 version)
1952 {
1953 	/* RDMA setup failed, switch back to TCP */
1954 	smc_conn_abort(new_smc, local_first);
1955 	if (reason_code < 0 ||
1956 	    smc_switch_to_fallback(new_smc, reason_code)) {
1957 		/* error, no fallback possible */
1958 		smc_listen_out_err(new_smc);
1959 		return;
1960 	}
1961 	if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1962 		if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1963 			smc_listen_out_err(new_smc);
1964 			return;
1965 		}
1966 	}
1967 	smc_listen_out_connected(new_smc);
1968 }
1969 
1970 /* listen worker: version checking */
1971 static int smc_listen_v2_check(struct smc_sock *new_smc,
1972 			       struct smc_clc_msg_proposal *pclc,
1973 			       struct smc_init_info *ini)
1974 {
1975 	struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1976 	struct smc_clc_v2_extension *pclc_v2_ext;
1977 	int rc = SMC_CLC_DECL_PEERNOSMC;
1978 
1979 	ini->smc_type_v1 = pclc->hdr.typev1;
1980 	ini->smc_type_v2 = pclc->hdr.typev2;
1981 	ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1982 	ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1983 	if (pclc->hdr.version > SMC_V1) {
1984 		if (smcd_indicated(ini->smc_type_v2))
1985 			ini->smcd_version |= SMC_V2;
1986 		if (smcr_indicated(ini->smc_type_v2))
1987 			ini->smcr_version |= SMC_V2;
1988 	}
1989 	if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1990 		rc = SMC_CLC_DECL_PEERNOSMC;
1991 		goto out;
1992 	}
1993 	pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1994 	if (!pclc_v2_ext) {
1995 		ini->smcd_version &= ~SMC_V2;
1996 		ini->smcr_version &= ~SMC_V2;
1997 		rc = SMC_CLC_DECL_NOV2EXT;
1998 		goto out;
1999 	}
2000 	pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
2001 	if (ini->smcd_version & SMC_V2) {
2002 		if (!smc_ism_is_v2_capable()) {
2003 			ini->smcd_version &= ~SMC_V2;
2004 			rc = SMC_CLC_DECL_NOISM2SUPP;
2005 		} else if (!pclc_smcd_v2_ext) {
2006 			ini->smcd_version &= ~SMC_V2;
2007 			rc = SMC_CLC_DECL_NOV2DEXT;
2008 		} else if (!pclc_v2_ext->hdr.eid_cnt &&
2009 			   !pclc_v2_ext->hdr.flag.seid) {
2010 			ini->smcd_version &= ~SMC_V2;
2011 			rc = SMC_CLC_DECL_NOUEID;
2012 		}
2013 	}
2014 	if (ini->smcr_version & SMC_V2) {
2015 		if (!pclc_v2_ext->hdr.eid_cnt) {
2016 			ini->smcr_version &= ~SMC_V2;
2017 			rc = SMC_CLC_DECL_NOUEID;
2018 		}
2019 	}
2020 
2021 	ini->release_nr = pclc_v2_ext->hdr.flag.release;
2022 	if (pclc_v2_ext->hdr.flag.release > SMC_RELEASE)
2023 		ini->release_nr = SMC_RELEASE;
2024 
2025 out:
2026 	if (!ini->smcd_version && !ini->smcr_version)
2027 		return rc;
2028 
2029 	return 0;
2030 }
2031 
2032 /* listen worker: check prefixes */
2033 static int smc_listen_prfx_check(struct smc_sock *new_smc,
2034 				 struct smc_clc_msg_proposal *pclc)
2035 {
2036 	struct smc_clc_msg_proposal_prefix *pclc_prfx;
2037 	struct socket *newclcsock = new_smc->clcsock;
2038 
2039 	if (pclc->hdr.typev1 == SMC_TYPE_N)
2040 		return 0;
2041 	pclc_prfx = smc_clc_proposal_get_prefix(pclc);
2042 	if (smc_clc_prfx_match(newclcsock, pclc_prfx))
2043 		return SMC_CLC_DECL_DIFFPREFIX;
2044 
2045 	return 0;
2046 }
2047 
2048 /* listen worker: initialize connection and buffers */
2049 static int smc_listen_rdma_init(struct smc_sock *new_smc,
2050 				struct smc_init_info *ini)
2051 {
2052 	int rc;
2053 
2054 	/* allocate connection / link group */
2055 	rc = smc_conn_create(new_smc, ini);
2056 	if (rc)
2057 		return rc;
2058 
2059 	/* create send buffer and rmb */
2060 	if (smc_buf_create(new_smc, false)) {
2061 		smc_conn_abort(new_smc, ini->first_contact_local);
2062 		return SMC_CLC_DECL_MEM;
2063 	}
2064 
2065 	return 0;
2066 }
2067 
2068 /* listen worker: initialize connection and buffers for SMC-D */
2069 static int smc_listen_ism_init(struct smc_sock *new_smc,
2070 			       struct smc_init_info *ini)
2071 {
2072 	int rc;
2073 
2074 	rc = smc_conn_create(new_smc, ini);
2075 	if (rc)
2076 		return rc;
2077 
2078 	/* Create send and receive buffers */
2079 	rc = smc_buf_create(new_smc, true);
2080 	if (rc) {
2081 		smc_conn_abort(new_smc, ini->first_contact_local);
2082 		return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2083 					 SMC_CLC_DECL_MEM;
2084 	}
2085 
2086 	return 0;
2087 }
2088 
2089 static bool smc_is_already_selected(struct smcd_dev *smcd,
2090 				    struct smc_init_info *ini,
2091 				    int matches)
2092 {
2093 	int i;
2094 
2095 	for (i = 0; i < matches; i++)
2096 		if (smcd == ini->ism_dev[i])
2097 			return true;
2098 
2099 	return false;
2100 }
2101 
2102 /* check for ISM devices matching proposed ISM devices */
2103 static void smc_check_ism_v2_match(struct smc_init_info *ini,
2104 				   u16 proposed_chid, u64 proposed_gid,
2105 				   unsigned int *matches)
2106 {
2107 	struct smcd_dev *smcd;
2108 
2109 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2110 		if (smcd->going_away)
2111 			continue;
2112 		if (smc_is_already_selected(smcd, ini, *matches))
2113 			continue;
2114 		if (smc_ism_get_chid(smcd) == proposed_chid &&
2115 		    !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2116 			ini->ism_peer_gid[*matches] = proposed_gid;
2117 			ini->ism_dev[*matches] = smcd;
2118 			(*matches)++;
2119 			break;
2120 		}
2121 	}
2122 }
2123 
2124 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2125 {
2126 	if (!ini->rc)
2127 		ini->rc = rc;
2128 }
2129 
2130 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2131 					struct smc_clc_msg_proposal *pclc,
2132 					struct smc_init_info *ini)
2133 {
2134 	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2135 	struct smc_clc_v2_extension *smc_v2_ext;
2136 	struct smc_clc_msg_smcd *pclc_smcd;
2137 	unsigned int matches = 0;
2138 	u8 smcd_version;
2139 	u8 *eid = NULL;
2140 	int i, rc;
2141 
2142 	if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2143 		goto not_found;
2144 
2145 	pclc_smcd = smc_get_clc_msg_smcd(pclc);
2146 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2147 	smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2148 
2149 	mutex_lock(&smcd_dev_list.mutex);
2150 	if (pclc_smcd->ism.chid)
2151 		/* check for ISM device matching proposed native ISM device */
2152 		smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2153 				       ntohll(pclc_smcd->ism.gid), &matches);
2154 	for (i = 1; i <= smc_v2_ext->hdr.ism_gid_cnt; i++) {
2155 		/* check for ISM devices matching proposed non-native ISM
2156 		 * devices
2157 		 */
2158 		smc_check_ism_v2_match(ini,
2159 				       ntohs(smcd_v2_ext->gidchid[i - 1].chid),
2160 				       ntohll(smcd_v2_ext->gidchid[i - 1].gid),
2161 				       &matches);
2162 	}
2163 	mutex_unlock(&smcd_dev_list.mutex);
2164 
2165 	if (!ini->ism_dev[0]) {
2166 		smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2167 		goto not_found;
2168 	}
2169 
2170 	smc_ism_get_system_eid(&eid);
2171 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2172 			       smcd_v2_ext->system_eid, eid))
2173 		goto not_found;
2174 
2175 	/* separate - outside the smcd_dev_list.lock */
2176 	smcd_version = ini->smcd_version;
2177 	for (i = 0; i < matches; i++) {
2178 		ini->smcd_version = SMC_V2;
2179 		ini->is_smcd = true;
2180 		ini->ism_selected = i;
2181 		rc = smc_listen_ism_init(new_smc, ini);
2182 		if (rc) {
2183 			smc_find_ism_store_rc(rc, ini);
2184 			/* try next active ISM device */
2185 			continue;
2186 		}
2187 		return; /* matching and usable V2 ISM device found */
2188 	}
2189 	/* no V2 ISM device could be initialized */
2190 	ini->smcd_version = smcd_version;	/* restore original value */
2191 	ini->negotiated_eid[0] = 0;
2192 
2193 not_found:
2194 	ini->smcd_version &= ~SMC_V2;
2195 	ini->ism_dev[0] = NULL;
2196 	ini->is_smcd = false;
2197 }
2198 
2199 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2200 					struct smc_clc_msg_proposal *pclc,
2201 					struct smc_init_info *ini)
2202 {
2203 	struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2204 	int rc = 0;
2205 
2206 	/* check if ISM V1 is available */
2207 	if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2208 		goto not_found;
2209 	ini->is_smcd = true; /* prepare ISM check */
2210 	ini->ism_peer_gid[0] = ntohll(pclc_smcd->ism.gid);
2211 	rc = smc_find_ism_device(new_smc, ini);
2212 	if (rc)
2213 		goto not_found;
2214 	ini->ism_selected = 0;
2215 	rc = smc_listen_ism_init(new_smc, ini);
2216 	if (!rc)
2217 		return;		/* V1 ISM device found */
2218 
2219 not_found:
2220 	smc_find_ism_store_rc(rc, ini);
2221 	ini->smcd_version &= ~SMC_V1;
2222 	ini->ism_dev[0] = NULL;
2223 	ini->is_smcd = false;
2224 }
2225 
2226 /* listen worker: register buffers */
2227 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2228 {
2229 	struct smc_connection *conn = &new_smc->conn;
2230 
2231 	if (!local_first) {
2232 		/* reg sendbufs if they were vzalloced */
2233 		if (conn->sndbuf_desc->is_vm) {
2234 			if (smcr_lgr_reg_sndbufs(conn->lnk,
2235 						 conn->sndbuf_desc))
2236 				return SMC_CLC_DECL_ERR_REGBUF;
2237 		}
2238 		if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2239 			return SMC_CLC_DECL_ERR_REGBUF;
2240 	}
2241 
2242 	return 0;
2243 }
2244 
2245 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2246 					 struct smc_clc_msg_proposal *pclc,
2247 					 struct smc_init_info *ini)
2248 {
2249 	struct smc_clc_v2_extension *smc_v2_ext;
2250 	u8 smcr_version;
2251 	int rc;
2252 
2253 	if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2254 		goto not_found;
2255 
2256 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2257 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2258 		goto not_found;
2259 
2260 	/* prepare RDMA check */
2261 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2262 	memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2263 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2264 	ini->check_smcrv2 = true;
2265 	ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2266 	ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2267 	ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2268 	rc = smc_find_rdma_device(new_smc, ini);
2269 	if (rc) {
2270 		smc_find_ism_store_rc(rc, ini);
2271 		goto not_found;
2272 	}
2273 	if (!ini->smcrv2.uses_gateway)
2274 		memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2275 
2276 	smcr_version = ini->smcr_version;
2277 	ini->smcr_version = SMC_V2;
2278 	rc = smc_listen_rdma_init(new_smc, ini);
2279 	if (!rc) {
2280 		rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2281 		if (rc)
2282 			smc_conn_abort(new_smc, ini->first_contact_local);
2283 	}
2284 	if (!rc)
2285 		return;
2286 	ini->smcr_version = smcr_version;
2287 	smc_find_ism_store_rc(rc, ini);
2288 
2289 not_found:
2290 	ini->smcr_version &= ~SMC_V2;
2291 	ini->smcrv2.ib_dev_v2 = NULL;
2292 	ini->check_smcrv2 = false;
2293 }
2294 
2295 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2296 					struct smc_clc_msg_proposal *pclc,
2297 					struct smc_init_info *ini)
2298 {
2299 	int rc;
2300 
2301 	if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2302 		return SMC_CLC_DECL_NOSMCDEV;
2303 
2304 	/* prepare RDMA check */
2305 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2306 	memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2307 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2308 	rc = smc_find_rdma_device(new_smc, ini);
2309 	if (rc) {
2310 		/* no RDMA device found */
2311 		return SMC_CLC_DECL_NOSMCDEV;
2312 	}
2313 	rc = smc_listen_rdma_init(new_smc, ini);
2314 	if (rc)
2315 		return rc;
2316 	return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2317 }
2318 
2319 /* determine the local device matching to proposal */
2320 static int smc_listen_find_device(struct smc_sock *new_smc,
2321 				  struct smc_clc_msg_proposal *pclc,
2322 				  struct smc_init_info *ini)
2323 {
2324 	int prfx_rc;
2325 
2326 	/* check for ISM device matching V2 proposed device */
2327 	smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2328 	if (ini->ism_dev[0])
2329 		return 0;
2330 
2331 	/* check for matching IP prefix and subnet length (V1) */
2332 	prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2333 	if (prfx_rc)
2334 		smc_find_ism_store_rc(prfx_rc, ini);
2335 
2336 	/* get vlan id from IP device */
2337 	if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2338 		return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2339 
2340 	/* check for ISM device matching V1 proposed device */
2341 	if (!prfx_rc)
2342 		smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2343 	if (ini->ism_dev[0])
2344 		return 0;
2345 
2346 	if (!smcr_indicated(pclc->hdr.typev1) &&
2347 	    !smcr_indicated(pclc->hdr.typev2))
2348 		/* skip RDMA and decline */
2349 		return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2350 
2351 	/* check if RDMA V2 is available */
2352 	smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2353 	if (ini->smcrv2.ib_dev_v2)
2354 		return 0;
2355 
2356 	/* check if RDMA V1 is available */
2357 	if (!prfx_rc) {
2358 		int rc;
2359 
2360 		rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2361 		smc_find_ism_store_rc(rc, ini);
2362 		return (!rc) ? 0 : ini->rc;
2363 	}
2364 	return SMC_CLC_DECL_NOSMCDEV;
2365 }
2366 
2367 /* listen worker: finish RDMA setup */
2368 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2369 				  struct smc_clc_msg_accept_confirm *cclc,
2370 				  bool local_first,
2371 				  struct smc_init_info *ini)
2372 {
2373 	struct smc_link *link = new_smc->conn.lnk;
2374 	int reason_code = 0;
2375 
2376 	if (local_first)
2377 		smc_link_save_peer_info(link, cclc, ini);
2378 
2379 	if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2380 		return SMC_CLC_DECL_ERR_RTOK;
2381 
2382 	if (local_first) {
2383 		if (smc_ib_ready_link(link))
2384 			return SMC_CLC_DECL_ERR_RDYLNK;
2385 		/* QP confirmation over RoCE fabric */
2386 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2387 		reason_code = smcr_serv_conf_first_link(new_smc);
2388 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2389 	}
2390 	return reason_code;
2391 }
2392 
2393 /* setup for connection of server */
2394 static void smc_listen_work(struct work_struct *work)
2395 {
2396 	struct smc_sock *new_smc = container_of(work, struct smc_sock,
2397 						smc_listen_work);
2398 	struct socket *newclcsock = new_smc->clcsock;
2399 	struct smc_clc_msg_accept_confirm *cclc;
2400 	struct smc_clc_msg_proposal_area *buf;
2401 	struct smc_clc_msg_proposal *pclc;
2402 	struct smc_init_info *ini = NULL;
2403 	u8 proposal_version = SMC_V1;
2404 	u8 accept_version;
2405 	int rc = 0;
2406 
2407 	if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2408 		return smc_listen_out_err(new_smc);
2409 
2410 	if (new_smc->use_fallback) {
2411 		smc_listen_out_connected(new_smc);
2412 		return;
2413 	}
2414 
2415 	/* check if peer is smc capable */
2416 	if (!tcp_sk(newclcsock->sk)->syn_smc) {
2417 		rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2418 		if (rc)
2419 			smc_listen_out_err(new_smc);
2420 		else
2421 			smc_listen_out_connected(new_smc);
2422 		return;
2423 	}
2424 
2425 	/* do inband token exchange -
2426 	 * wait for and receive SMC Proposal CLC message
2427 	 */
2428 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2429 	if (!buf) {
2430 		rc = SMC_CLC_DECL_MEM;
2431 		goto out_decl;
2432 	}
2433 	pclc = (struct smc_clc_msg_proposal *)buf;
2434 	rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2435 			      SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2436 	if (rc)
2437 		goto out_decl;
2438 
2439 	if (pclc->hdr.version > SMC_V1)
2440 		proposal_version = SMC_V2;
2441 
2442 	/* IPSec connections opt out of SMC optimizations */
2443 	if (using_ipsec(new_smc)) {
2444 		rc = SMC_CLC_DECL_IPSEC;
2445 		goto out_decl;
2446 	}
2447 
2448 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2449 	if (!ini) {
2450 		rc = SMC_CLC_DECL_MEM;
2451 		goto out_decl;
2452 	}
2453 
2454 	/* initial version checking */
2455 	rc = smc_listen_v2_check(new_smc, pclc, ini);
2456 	if (rc)
2457 		goto out_decl;
2458 
2459 	rc = smc_clc_srv_v2x_features_validate(pclc, ini);
2460 	if (rc)
2461 		goto out_decl;
2462 
2463 	mutex_lock(&smc_server_lgr_pending);
2464 	smc_close_init(new_smc);
2465 	smc_rx_init(new_smc);
2466 	smc_tx_init(new_smc);
2467 
2468 	/* determine ISM or RoCE device used for connection */
2469 	rc = smc_listen_find_device(new_smc, pclc, ini);
2470 	if (rc)
2471 		goto out_unlock;
2472 
2473 	/* send SMC Accept CLC message */
2474 	accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2475 	rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2476 				 accept_version, ini->negotiated_eid, ini);
2477 	if (rc)
2478 		goto out_unlock;
2479 
2480 	/* SMC-D does not need this lock any more */
2481 	if (ini->is_smcd)
2482 		mutex_unlock(&smc_server_lgr_pending);
2483 
2484 	/* receive SMC Confirm CLC message */
2485 	memset(buf, 0, sizeof(*buf));
2486 	cclc = (struct smc_clc_msg_accept_confirm *)buf;
2487 	rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2488 			      SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2489 	if (rc) {
2490 		if (!ini->is_smcd)
2491 			goto out_unlock;
2492 		goto out_decl;
2493 	}
2494 
2495 	rc = smc_clc_v2x_features_confirm_check(cclc, ini);
2496 	if (rc) {
2497 		if (!ini->is_smcd)
2498 			goto out_unlock;
2499 		goto out_decl;
2500 	}
2501 
2502 	/* fce smc release version is needed in smc_listen_rdma_finish,
2503 	 * so save fce info here.
2504 	 */
2505 	smc_conn_save_peer_info_fce(new_smc, cclc);
2506 
2507 	/* finish worker */
2508 	if (!ini->is_smcd) {
2509 		rc = smc_listen_rdma_finish(new_smc, cclc,
2510 					    ini->first_contact_local, ini);
2511 		if (rc)
2512 			goto out_unlock;
2513 		mutex_unlock(&smc_server_lgr_pending);
2514 	}
2515 	smc_conn_save_peer_info(new_smc, cclc);
2516 	smc_listen_out_connected(new_smc);
2517 	SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2518 	goto out_free;
2519 
2520 out_unlock:
2521 	mutex_unlock(&smc_server_lgr_pending);
2522 out_decl:
2523 	smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2524 			   proposal_version);
2525 out_free:
2526 	kfree(ini);
2527 	kfree(buf);
2528 }
2529 
2530 static void smc_tcp_listen_work(struct work_struct *work)
2531 {
2532 	struct smc_sock *lsmc = container_of(work, struct smc_sock,
2533 					     tcp_listen_work);
2534 	struct sock *lsk = &lsmc->sk;
2535 	struct smc_sock *new_smc;
2536 	int rc = 0;
2537 
2538 	lock_sock(lsk);
2539 	while (lsk->sk_state == SMC_LISTEN) {
2540 		rc = smc_clcsock_accept(lsmc, &new_smc);
2541 		if (rc) /* clcsock accept queue empty or error */
2542 			goto out;
2543 		if (!new_smc)
2544 			continue;
2545 
2546 		if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2547 			atomic_inc(&lsmc->queued_smc_hs);
2548 
2549 		new_smc->listen_smc = lsmc;
2550 		new_smc->use_fallback = lsmc->use_fallback;
2551 		new_smc->fallback_rsn = lsmc->fallback_rsn;
2552 		sock_hold(lsk); /* sock_put in smc_listen_work */
2553 		INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2554 		smc_copy_sock_settings_to_smc(new_smc);
2555 		sock_hold(&new_smc->sk); /* sock_put in passive closing */
2556 		if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2557 			sock_put(&new_smc->sk);
2558 	}
2559 
2560 out:
2561 	release_sock(lsk);
2562 	sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2563 }
2564 
2565 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2566 {
2567 	struct smc_sock *lsmc;
2568 
2569 	read_lock_bh(&listen_clcsock->sk_callback_lock);
2570 	lsmc = smc_clcsock_user_data(listen_clcsock);
2571 	if (!lsmc)
2572 		goto out;
2573 	lsmc->clcsk_data_ready(listen_clcsock);
2574 	if (lsmc->sk.sk_state == SMC_LISTEN) {
2575 		sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2576 		if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2577 			sock_put(&lsmc->sk);
2578 	}
2579 out:
2580 	read_unlock_bh(&listen_clcsock->sk_callback_lock);
2581 }
2582 
2583 static int smc_listen(struct socket *sock, int backlog)
2584 {
2585 	struct sock *sk = sock->sk;
2586 	struct smc_sock *smc;
2587 	int rc;
2588 
2589 	smc = smc_sk(sk);
2590 	lock_sock(sk);
2591 
2592 	rc = -EINVAL;
2593 	if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2594 	    smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2595 		goto out;
2596 
2597 	rc = 0;
2598 	if (sk->sk_state == SMC_LISTEN) {
2599 		sk->sk_max_ack_backlog = backlog;
2600 		goto out;
2601 	}
2602 	/* some socket options are handled in core, so we could not apply
2603 	 * them to the clc socket -- copy smc socket options to clc socket
2604 	 */
2605 	smc_copy_sock_settings_to_clc(smc);
2606 	if (!smc->use_fallback)
2607 		tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2608 
2609 	/* save original sk_data_ready function and establish
2610 	 * smc-specific sk_data_ready function
2611 	 */
2612 	write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2613 	smc->clcsock->sk->sk_user_data =
2614 		(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2615 	smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2616 			       smc_clcsock_data_ready, &smc->clcsk_data_ready);
2617 	write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2618 
2619 	/* save original ops */
2620 	smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2621 
2622 	smc->af_ops = *smc->ori_af_ops;
2623 	smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2624 
2625 	inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2626 
2627 	if (smc->limit_smc_hs)
2628 		tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2629 
2630 	rc = kernel_listen(smc->clcsock, backlog);
2631 	if (rc) {
2632 		write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2633 		smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2634 				       &smc->clcsk_data_ready);
2635 		smc->clcsock->sk->sk_user_data = NULL;
2636 		write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2637 		goto out;
2638 	}
2639 	sk->sk_max_ack_backlog = backlog;
2640 	sk->sk_ack_backlog = 0;
2641 	sk->sk_state = SMC_LISTEN;
2642 
2643 out:
2644 	release_sock(sk);
2645 	return rc;
2646 }
2647 
2648 static int smc_accept(struct socket *sock, struct socket *new_sock,
2649 		      int flags, bool kern)
2650 {
2651 	struct sock *sk = sock->sk, *nsk;
2652 	DECLARE_WAITQUEUE(wait, current);
2653 	struct smc_sock *lsmc;
2654 	long timeo;
2655 	int rc = 0;
2656 
2657 	lsmc = smc_sk(sk);
2658 	sock_hold(sk); /* sock_put below */
2659 	lock_sock(sk);
2660 
2661 	if (lsmc->sk.sk_state != SMC_LISTEN) {
2662 		rc = -EINVAL;
2663 		release_sock(sk);
2664 		goto out;
2665 	}
2666 
2667 	/* Wait for an incoming connection */
2668 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2669 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
2670 	while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2671 		set_current_state(TASK_INTERRUPTIBLE);
2672 		if (!timeo) {
2673 			rc = -EAGAIN;
2674 			break;
2675 		}
2676 		release_sock(sk);
2677 		timeo = schedule_timeout(timeo);
2678 		/* wakeup by sk_data_ready in smc_listen_work() */
2679 		sched_annotate_sleep();
2680 		lock_sock(sk);
2681 		if (signal_pending(current)) {
2682 			rc = sock_intr_errno(timeo);
2683 			break;
2684 		}
2685 	}
2686 	set_current_state(TASK_RUNNING);
2687 	remove_wait_queue(sk_sleep(sk), &wait);
2688 
2689 	if (!rc)
2690 		rc = sock_error(nsk);
2691 	release_sock(sk);
2692 	if (rc)
2693 		goto out;
2694 
2695 	if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
2696 		/* wait till data arrives on the socket */
2697 		timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2698 								MSEC_PER_SEC);
2699 		if (smc_sk(nsk)->use_fallback) {
2700 			struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2701 
2702 			lock_sock(clcsk);
2703 			if (skb_queue_empty(&clcsk->sk_receive_queue))
2704 				sk_wait_data(clcsk, &timeo, NULL);
2705 			release_sock(clcsk);
2706 		} else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2707 			lock_sock(nsk);
2708 			smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2709 			release_sock(nsk);
2710 		}
2711 	}
2712 
2713 out:
2714 	sock_put(sk); /* sock_hold above */
2715 	return rc;
2716 }
2717 
2718 static int smc_getname(struct socket *sock, struct sockaddr *addr,
2719 		       int peer)
2720 {
2721 	struct smc_sock *smc;
2722 
2723 	if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2724 	    (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2725 		return -ENOTCONN;
2726 
2727 	smc = smc_sk(sock->sk);
2728 
2729 	return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2730 }
2731 
2732 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2733 {
2734 	struct sock *sk = sock->sk;
2735 	struct smc_sock *smc;
2736 	int rc;
2737 
2738 	smc = smc_sk(sk);
2739 	lock_sock(sk);
2740 
2741 	/* SMC does not support connect with fastopen */
2742 	if (msg->msg_flags & MSG_FASTOPEN) {
2743 		/* not connected yet, fallback */
2744 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2745 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2746 			if (rc)
2747 				goto out;
2748 		} else {
2749 			rc = -EINVAL;
2750 			goto out;
2751 		}
2752 	} else if ((sk->sk_state != SMC_ACTIVE) &&
2753 		   (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2754 		   (sk->sk_state != SMC_INIT)) {
2755 		rc = -EPIPE;
2756 		goto out;
2757 	}
2758 
2759 	if (smc->use_fallback) {
2760 		rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2761 	} else {
2762 		rc = smc_tx_sendmsg(smc, msg, len);
2763 		SMC_STAT_TX_PAYLOAD(smc, len, rc);
2764 	}
2765 out:
2766 	release_sock(sk);
2767 	return rc;
2768 }
2769 
2770 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2771 		       int flags)
2772 {
2773 	struct sock *sk = sock->sk;
2774 	struct smc_sock *smc;
2775 	int rc = -ENOTCONN;
2776 
2777 	smc = smc_sk(sk);
2778 	lock_sock(sk);
2779 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2780 		/* socket was connected before, no more data to read */
2781 		rc = 0;
2782 		goto out;
2783 	}
2784 	if ((sk->sk_state == SMC_INIT) ||
2785 	    (sk->sk_state == SMC_LISTEN) ||
2786 	    (sk->sk_state == SMC_CLOSED))
2787 		goto out;
2788 
2789 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2790 		rc = 0;
2791 		goto out;
2792 	}
2793 
2794 	if (smc->use_fallback) {
2795 		rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2796 	} else {
2797 		msg->msg_namelen = 0;
2798 		rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2799 		SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2800 	}
2801 
2802 out:
2803 	release_sock(sk);
2804 	return rc;
2805 }
2806 
2807 static __poll_t smc_accept_poll(struct sock *parent)
2808 {
2809 	struct smc_sock *isk = smc_sk(parent);
2810 	__poll_t mask = 0;
2811 
2812 	spin_lock(&isk->accept_q_lock);
2813 	if (!list_empty(&isk->accept_q))
2814 		mask = EPOLLIN | EPOLLRDNORM;
2815 	spin_unlock(&isk->accept_q_lock);
2816 
2817 	return mask;
2818 }
2819 
2820 static __poll_t smc_poll(struct file *file, struct socket *sock,
2821 			     poll_table *wait)
2822 {
2823 	struct sock *sk = sock->sk;
2824 	struct smc_sock *smc;
2825 	__poll_t mask = 0;
2826 
2827 	if (!sk)
2828 		return EPOLLNVAL;
2829 
2830 	smc = smc_sk(sock->sk);
2831 	if (smc->use_fallback) {
2832 		/* delegate to CLC child sock */
2833 		mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2834 		sk->sk_err = smc->clcsock->sk->sk_err;
2835 	} else {
2836 		if (sk->sk_state != SMC_CLOSED)
2837 			sock_poll_wait(file, sock, wait);
2838 		if (sk->sk_err)
2839 			mask |= EPOLLERR;
2840 		if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2841 		    (sk->sk_state == SMC_CLOSED))
2842 			mask |= EPOLLHUP;
2843 		if (sk->sk_state == SMC_LISTEN) {
2844 			/* woken up by sk_data_ready in smc_listen_work() */
2845 			mask |= smc_accept_poll(sk);
2846 		} else if (smc->use_fallback) { /* as result of connect_work()*/
2847 			mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2848 							   wait);
2849 			sk->sk_err = smc->clcsock->sk->sk_err;
2850 		} else {
2851 			if ((sk->sk_state != SMC_INIT &&
2852 			     atomic_read(&smc->conn.sndbuf_space)) ||
2853 			    sk->sk_shutdown & SEND_SHUTDOWN) {
2854 				mask |= EPOLLOUT | EPOLLWRNORM;
2855 			} else {
2856 				sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2857 				set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2858 			}
2859 			if (atomic_read(&smc->conn.bytes_to_rcv))
2860 				mask |= EPOLLIN | EPOLLRDNORM;
2861 			if (sk->sk_shutdown & RCV_SHUTDOWN)
2862 				mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2863 			if (sk->sk_state == SMC_APPCLOSEWAIT1)
2864 				mask |= EPOLLIN;
2865 			if (smc->conn.urg_state == SMC_URG_VALID)
2866 				mask |= EPOLLPRI;
2867 		}
2868 	}
2869 
2870 	return mask;
2871 }
2872 
2873 static int smc_shutdown(struct socket *sock, int how)
2874 {
2875 	struct sock *sk = sock->sk;
2876 	bool do_shutdown = true;
2877 	struct smc_sock *smc;
2878 	int rc = -EINVAL;
2879 	int old_state;
2880 	int rc1 = 0;
2881 
2882 	smc = smc_sk(sk);
2883 
2884 	if ((how < SHUT_RD) || (how > SHUT_RDWR))
2885 		return rc;
2886 
2887 	lock_sock(sk);
2888 
2889 	if (sock->state == SS_CONNECTING) {
2890 		if (sk->sk_state == SMC_ACTIVE)
2891 			sock->state = SS_CONNECTED;
2892 		else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2893 			 sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2894 			 sk->sk_state == SMC_APPCLOSEWAIT1 ||
2895 			 sk->sk_state == SMC_APPCLOSEWAIT2 ||
2896 			 sk->sk_state == SMC_APPFINCLOSEWAIT)
2897 			sock->state = SS_DISCONNECTING;
2898 	}
2899 
2900 	rc = -ENOTCONN;
2901 	if ((sk->sk_state != SMC_ACTIVE) &&
2902 	    (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2903 	    (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2904 	    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2905 	    (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2906 	    (sk->sk_state != SMC_APPFINCLOSEWAIT))
2907 		goto out;
2908 	if (smc->use_fallback) {
2909 		rc = kernel_sock_shutdown(smc->clcsock, how);
2910 		sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2911 		if (sk->sk_shutdown == SHUTDOWN_MASK) {
2912 			sk->sk_state = SMC_CLOSED;
2913 			sk->sk_socket->state = SS_UNCONNECTED;
2914 			sock_put(sk);
2915 		}
2916 		goto out;
2917 	}
2918 	switch (how) {
2919 	case SHUT_RDWR:		/* shutdown in both directions */
2920 		old_state = sk->sk_state;
2921 		rc = smc_close_active(smc);
2922 		if (old_state == SMC_ACTIVE &&
2923 		    sk->sk_state == SMC_PEERCLOSEWAIT1)
2924 			do_shutdown = false;
2925 		break;
2926 	case SHUT_WR:
2927 		rc = smc_close_shutdown_write(smc);
2928 		break;
2929 	case SHUT_RD:
2930 		rc = 0;
2931 		/* nothing more to do because peer is not involved */
2932 		break;
2933 	}
2934 	if (do_shutdown && smc->clcsock)
2935 		rc1 = kernel_sock_shutdown(smc->clcsock, how);
2936 	/* map sock_shutdown_cmd constants to sk_shutdown value range */
2937 	sk->sk_shutdown |= how + 1;
2938 
2939 	if (sk->sk_state == SMC_CLOSED)
2940 		sock->state = SS_UNCONNECTED;
2941 	else
2942 		sock->state = SS_DISCONNECTING;
2943 out:
2944 	release_sock(sk);
2945 	return rc ? rc : rc1;
2946 }
2947 
2948 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2949 			    char __user *optval, int __user *optlen)
2950 {
2951 	struct smc_sock *smc;
2952 	int val, len;
2953 
2954 	smc = smc_sk(sock->sk);
2955 
2956 	if (get_user(len, optlen))
2957 		return -EFAULT;
2958 
2959 	len = min_t(int, len, sizeof(int));
2960 
2961 	if (len < 0)
2962 		return -EINVAL;
2963 
2964 	switch (optname) {
2965 	case SMC_LIMIT_HS:
2966 		val = smc->limit_smc_hs;
2967 		break;
2968 	default:
2969 		return -EOPNOTSUPP;
2970 	}
2971 
2972 	if (put_user(len, optlen))
2973 		return -EFAULT;
2974 	if (copy_to_user(optval, &val, len))
2975 		return -EFAULT;
2976 
2977 	return 0;
2978 }
2979 
2980 static int __smc_setsockopt(struct socket *sock, int level, int optname,
2981 			    sockptr_t optval, unsigned int optlen)
2982 {
2983 	struct sock *sk = sock->sk;
2984 	struct smc_sock *smc;
2985 	int val, rc;
2986 
2987 	smc = smc_sk(sk);
2988 
2989 	lock_sock(sk);
2990 	switch (optname) {
2991 	case SMC_LIMIT_HS:
2992 		if (optlen < sizeof(int)) {
2993 			rc = -EINVAL;
2994 			break;
2995 		}
2996 		if (copy_from_sockptr(&val, optval, sizeof(int))) {
2997 			rc = -EFAULT;
2998 			break;
2999 		}
3000 
3001 		smc->limit_smc_hs = !!val;
3002 		rc = 0;
3003 		break;
3004 	default:
3005 		rc = -EOPNOTSUPP;
3006 		break;
3007 	}
3008 	release_sock(sk);
3009 
3010 	return rc;
3011 }
3012 
3013 static int smc_setsockopt(struct socket *sock, int level, int optname,
3014 			  sockptr_t optval, unsigned int optlen)
3015 {
3016 	struct sock *sk = sock->sk;
3017 	struct smc_sock *smc;
3018 	int val, rc;
3019 
3020 	if (level == SOL_TCP && optname == TCP_ULP)
3021 		return -EOPNOTSUPP;
3022 	else if (level == SOL_SMC)
3023 		return __smc_setsockopt(sock, level, optname, optval, optlen);
3024 
3025 	smc = smc_sk(sk);
3026 
3027 	/* generic setsockopts reaching us here always apply to the
3028 	 * CLC socket
3029 	 */
3030 	mutex_lock(&smc->clcsock_release_lock);
3031 	if (!smc->clcsock) {
3032 		mutex_unlock(&smc->clcsock_release_lock);
3033 		return -EBADF;
3034 	}
3035 	if (unlikely(!smc->clcsock->ops->setsockopt))
3036 		rc = -EOPNOTSUPP;
3037 	else
3038 		rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
3039 						   optval, optlen);
3040 	if (smc->clcsock->sk->sk_err) {
3041 		sk->sk_err = smc->clcsock->sk->sk_err;
3042 		sk_error_report(sk);
3043 	}
3044 	mutex_unlock(&smc->clcsock_release_lock);
3045 
3046 	if (optlen < sizeof(int))
3047 		return -EINVAL;
3048 	if (copy_from_sockptr(&val, optval, sizeof(int)))
3049 		return -EFAULT;
3050 
3051 	lock_sock(sk);
3052 	if (rc || smc->use_fallback)
3053 		goto out;
3054 	switch (optname) {
3055 	case TCP_FASTOPEN:
3056 	case TCP_FASTOPEN_CONNECT:
3057 	case TCP_FASTOPEN_KEY:
3058 	case TCP_FASTOPEN_NO_COOKIE:
3059 		/* option not supported by SMC */
3060 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
3061 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
3062 		} else {
3063 			rc = -EINVAL;
3064 		}
3065 		break;
3066 	case TCP_NODELAY:
3067 		if (sk->sk_state != SMC_INIT &&
3068 		    sk->sk_state != SMC_LISTEN &&
3069 		    sk->sk_state != SMC_CLOSED) {
3070 			if (val) {
3071 				SMC_STAT_INC(smc, ndly_cnt);
3072 				smc_tx_pending(&smc->conn);
3073 				cancel_delayed_work(&smc->conn.tx_work);
3074 			}
3075 		}
3076 		break;
3077 	case TCP_CORK:
3078 		if (sk->sk_state != SMC_INIT &&
3079 		    sk->sk_state != SMC_LISTEN &&
3080 		    sk->sk_state != SMC_CLOSED) {
3081 			if (!val) {
3082 				SMC_STAT_INC(smc, cork_cnt);
3083 				smc_tx_pending(&smc->conn);
3084 				cancel_delayed_work(&smc->conn.tx_work);
3085 			}
3086 		}
3087 		break;
3088 	case TCP_DEFER_ACCEPT:
3089 		smc->sockopt_defer_accept = val;
3090 		break;
3091 	default:
3092 		break;
3093 	}
3094 out:
3095 	release_sock(sk);
3096 
3097 	return rc;
3098 }
3099 
3100 static int smc_getsockopt(struct socket *sock, int level, int optname,
3101 			  char __user *optval, int __user *optlen)
3102 {
3103 	struct smc_sock *smc;
3104 	int rc;
3105 
3106 	if (level == SOL_SMC)
3107 		return __smc_getsockopt(sock, level, optname, optval, optlen);
3108 
3109 	smc = smc_sk(sock->sk);
3110 	mutex_lock(&smc->clcsock_release_lock);
3111 	if (!smc->clcsock) {
3112 		mutex_unlock(&smc->clcsock_release_lock);
3113 		return -EBADF;
3114 	}
3115 	/* socket options apply to the CLC socket */
3116 	if (unlikely(!smc->clcsock->ops->getsockopt)) {
3117 		mutex_unlock(&smc->clcsock_release_lock);
3118 		return -EOPNOTSUPP;
3119 	}
3120 	rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3121 					   optval, optlen);
3122 	mutex_unlock(&smc->clcsock_release_lock);
3123 	return rc;
3124 }
3125 
3126 static int smc_ioctl(struct socket *sock, unsigned int cmd,
3127 		     unsigned long arg)
3128 {
3129 	union smc_host_cursor cons, urg;
3130 	struct smc_connection *conn;
3131 	struct smc_sock *smc;
3132 	int answ;
3133 
3134 	smc = smc_sk(sock->sk);
3135 	conn = &smc->conn;
3136 	lock_sock(&smc->sk);
3137 	if (smc->use_fallback) {
3138 		if (!smc->clcsock) {
3139 			release_sock(&smc->sk);
3140 			return -EBADF;
3141 		}
3142 		answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3143 		release_sock(&smc->sk);
3144 		return answ;
3145 	}
3146 	switch (cmd) {
3147 	case SIOCINQ: /* same as FIONREAD */
3148 		if (smc->sk.sk_state == SMC_LISTEN) {
3149 			release_sock(&smc->sk);
3150 			return -EINVAL;
3151 		}
3152 		if (smc->sk.sk_state == SMC_INIT ||
3153 		    smc->sk.sk_state == SMC_CLOSED)
3154 			answ = 0;
3155 		else
3156 			answ = atomic_read(&smc->conn.bytes_to_rcv);
3157 		break;
3158 	case SIOCOUTQ:
3159 		/* output queue size (not send + not acked) */
3160 		if (smc->sk.sk_state == SMC_LISTEN) {
3161 			release_sock(&smc->sk);
3162 			return -EINVAL;
3163 		}
3164 		if (smc->sk.sk_state == SMC_INIT ||
3165 		    smc->sk.sk_state == SMC_CLOSED)
3166 			answ = 0;
3167 		else
3168 			answ = smc->conn.sndbuf_desc->len -
3169 					atomic_read(&smc->conn.sndbuf_space);
3170 		break;
3171 	case SIOCOUTQNSD:
3172 		/* output queue size (not send only) */
3173 		if (smc->sk.sk_state == SMC_LISTEN) {
3174 			release_sock(&smc->sk);
3175 			return -EINVAL;
3176 		}
3177 		if (smc->sk.sk_state == SMC_INIT ||
3178 		    smc->sk.sk_state == SMC_CLOSED)
3179 			answ = 0;
3180 		else
3181 			answ = smc_tx_prepared_sends(&smc->conn);
3182 		break;
3183 	case SIOCATMARK:
3184 		if (smc->sk.sk_state == SMC_LISTEN) {
3185 			release_sock(&smc->sk);
3186 			return -EINVAL;
3187 		}
3188 		if (smc->sk.sk_state == SMC_INIT ||
3189 		    smc->sk.sk_state == SMC_CLOSED) {
3190 			answ = 0;
3191 		} else {
3192 			smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3193 			smc_curs_copy(&urg, &conn->urg_curs, conn);
3194 			answ = smc_curs_diff(conn->rmb_desc->len,
3195 					     &cons, &urg) == 1;
3196 		}
3197 		break;
3198 	default:
3199 		release_sock(&smc->sk);
3200 		return -ENOIOCTLCMD;
3201 	}
3202 	release_sock(&smc->sk);
3203 
3204 	return put_user(answ, (int __user *)arg);
3205 }
3206 
3207 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3208  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3209  * updates till whenever a respective page has been fully processed.
3210  * Note that subsequent recv() calls have to wait till all splice() processing
3211  * completed.
3212  */
3213 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3214 			       struct pipe_inode_info *pipe, size_t len,
3215 			       unsigned int flags)
3216 {
3217 	struct sock *sk = sock->sk;
3218 	struct smc_sock *smc;
3219 	int rc = -ENOTCONN;
3220 
3221 	smc = smc_sk(sk);
3222 	lock_sock(sk);
3223 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3224 		/* socket was connected before, no more data to read */
3225 		rc = 0;
3226 		goto out;
3227 	}
3228 	if (sk->sk_state == SMC_INIT ||
3229 	    sk->sk_state == SMC_LISTEN ||
3230 	    sk->sk_state == SMC_CLOSED)
3231 		goto out;
3232 
3233 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3234 		rc = 0;
3235 		goto out;
3236 	}
3237 
3238 	if (smc->use_fallback) {
3239 		rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3240 						    pipe, len, flags);
3241 	} else {
3242 		if (*ppos) {
3243 			rc = -ESPIPE;
3244 			goto out;
3245 		}
3246 		if (flags & SPLICE_F_NONBLOCK)
3247 			flags = MSG_DONTWAIT;
3248 		else
3249 			flags = 0;
3250 		SMC_STAT_INC(smc, splice_cnt);
3251 		rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3252 	}
3253 out:
3254 	release_sock(sk);
3255 
3256 	return rc;
3257 }
3258 
3259 /* must look like tcp */
3260 static const struct proto_ops smc_sock_ops = {
3261 	.family		= PF_SMC,
3262 	.owner		= THIS_MODULE,
3263 	.release	= smc_release,
3264 	.bind		= smc_bind,
3265 	.connect	= smc_connect,
3266 	.socketpair	= sock_no_socketpair,
3267 	.accept		= smc_accept,
3268 	.getname	= smc_getname,
3269 	.poll		= smc_poll,
3270 	.ioctl		= smc_ioctl,
3271 	.listen		= smc_listen,
3272 	.shutdown	= smc_shutdown,
3273 	.setsockopt	= smc_setsockopt,
3274 	.getsockopt	= smc_getsockopt,
3275 	.sendmsg	= smc_sendmsg,
3276 	.recvmsg	= smc_recvmsg,
3277 	.mmap		= sock_no_mmap,
3278 	.splice_read	= smc_splice_read,
3279 };
3280 
3281 static int __smc_create(struct net *net, struct socket *sock, int protocol,
3282 			int kern, struct socket *clcsock)
3283 {
3284 	int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3285 	struct smc_sock *smc;
3286 	struct sock *sk;
3287 	int rc;
3288 
3289 	rc = -ESOCKTNOSUPPORT;
3290 	if (sock->type != SOCK_STREAM)
3291 		goto out;
3292 
3293 	rc = -EPROTONOSUPPORT;
3294 	if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3295 		goto out;
3296 
3297 	rc = -ENOBUFS;
3298 	sock->ops = &smc_sock_ops;
3299 	sock->state = SS_UNCONNECTED;
3300 	sk = smc_sock_alloc(net, sock, protocol);
3301 	if (!sk)
3302 		goto out;
3303 
3304 	/* create internal TCP socket for CLC handshake and fallback */
3305 	smc = smc_sk(sk);
3306 	smc->use_fallback = false; /* assume rdma capability first */
3307 	smc->fallback_rsn = 0;
3308 
3309 	/* default behavior from limit_smc_hs in every net namespace */
3310 	smc->limit_smc_hs = net->smc.limit_smc_hs;
3311 
3312 	rc = 0;
3313 	if (!clcsock) {
3314 		rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3315 				      &smc->clcsock);
3316 		if (rc) {
3317 			sk_common_release(sk);
3318 			goto out;
3319 		}
3320 
3321 		/* smc_clcsock_release() does not wait smc->clcsock->sk's
3322 		 * destruction;  its sk_state might not be TCP_CLOSE after
3323 		 * smc->sk is close()d, and TCP timers can be fired later,
3324 		 * which need net ref.
3325 		 */
3326 		sk = smc->clcsock->sk;
3327 		__netns_tracker_free(net, &sk->ns_tracker, false);
3328 		sk->sk_net_refcnt = 1;
3329 		get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
3330 		sock_inuse_add(net, 1);
3331 	} else {
3332 		smc->clcsock = clcsock;
3333 	}
3334 
3335 out:
3336 	return rc;
3337 }
3338 
3339 static int smc_create(struct net *net, struct socket *sock, int protocol,
3340 		      int kern)
3341 {
3342 	return __smc_create(net, sock, protocol, kern, NULL);
3343 }
3344 
3345 static const struct net_proto_family smc_sock_family_ops = {
3346 	.family	= PF_SMC,
3347 	.owner	= THIS_MODULE,
3348 	.create	= smc_create,
3349 };
3350 
3351 static int smc_ulp_init(struct sock *sk)
3352 {
3353 	struct socket *tcp = sk->sk_socket;
3354 	struct net *net = sock_net(sk);
3355 	struct socket *smcsock;
3356 	int protocol, ret;
3357 
3358 	/* only TCP can be replaced */
3359 	if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3360 	    (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3361 		return -ESOCKTNOSUPPORT;
3362 	/* don't handle wq now */
3363 	if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3364 		return -ENOTCONN;
3365 
3366 	if (sk->sk_family == AF_INET)
3367 		protocol = SMCPROTO_SMC;
3368 	else
3369 		protocol = SMCPROTO_SMC6;
3370 
3371 	smcsock = sock_alloc();
3372 	if (!smcsock)
3373 		return -ENFILE;
3374 
3375 	smcsock->type = SOCK_STREAM;
3376 	__module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3377 	ret = __smc_create(net, smcsock, protocol, 1, tcp);
3378 	if (ret) {
3379 		sock_release(smcsock); /* module_put() which ops won't be NULL */
3380 		return ret;
3381 	}
3382 
3383 	/* replace tcp socket to smc */
3384 	smcsock->file = tcp->file;
3385 	smcsock->file->private_data = smcsock;
3386 	smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3387 	smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3388 	tcp->file = NULL;
3389 
3390 	return ret;
3391 }
3392 
3393 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3394 			  const gfp_t priority)
3395 {
3396 	struct inet_connection_sock *icsk = inet_csk(newsk);
3397 
3398 	/* don't inherit ulp ops to child when listen */
3399 	icsk->icsk_ulp_ops = NULL;
3400 }
3401 
3402 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3403 	.name		= "smc",
3404 	.owner		= THIS_MODULE,
3405 	.init		= smc_ulp_init,
3406 	.clone		= smc_ulp_clone,
3407 };
3408 
3409 unsigned int smc_net_id;
3410 
3411 static __net_init int smc_net_init(struct net *net)
3412 {
3413 	int rc;
3414 
3415 	rc = smc_sysctl_net_init(net);
3416 	if (rc)
3417 		return rc;
3418 	return smc_pnet_net_init(net);
3419 }
3420 
3421 static void __net_exit smc_net_exit(struct net *net)
3422 {
3423 	smc_sysctl_net_exit(net);
3424 	smc_pnet_net_exit(net);
3425 }
3426 
3427 static __net_init int smc_net_stat_init(struct net *net)
3428 {
3429 	return smc_stats_init(net);
3430 }
3431 
3432 static void __net_exit smc_net_stat_exit(struct net *net)
3433 {
3434 	smc_stats_exit(net);
3435 }
3436 
3437 static struct pernet_operations smc_net_ops = {
3438 	.init = smc_net_init,
3439 	.exit = smc_net_exit,
3440 	.id   = &smc_net_id,
3441 	.size = sizeof(struct smc_net),
3442 };
3443 
3444 static struct pernet_operations smc_net_stat_ops = {
3445 	.init = smc_net_stat_init,
3446 	.exit = smc_net_stat_exit,
3447 };
3448 
3449 static int __init smc_init(void)
3450 {
3451 	int rc;
3452 
3453 	rc = register_pernet_subsys(&smc_net_ops);
3454 	if (rc)
3455 		return rc;
3456 
3457 	rc = register_pernet_subsys(&smc_net_stat_ops);
3458 	if (rc)
3459 		goto out_pernet_subsys;
3460 
3461 	rc = smc_ism_init();
3462 	if (rc)
3463 		goto out_pernet_subsys_stat;
3464 	smc_clc_init();
3465 
3466 	rc = smc_nl_init();
3467 	if (rc)
3468 		goto out_ism;
3469 
3470 	rc = smc_pnet_init();
3471 	if (rc)
3472 		goto out_nl;
3473 
3474 	rc = -ENOMEM;
3475 
3476 	smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3477 	if (!smc_tcp_ls_wq)
3478 		goto out_pnet;
3479 
3480 	smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3481 	if (!smc_hs_wq)
3482 		goto out_alloc_tcp_ls_wq;
3483 
3484 	smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3485 	if (!smc_close_wq)
3486 		goto out_alloc_hs_wq;
3487 
3488 	rc = smc_core_init();
3489 	if (rc) {
3490 		pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3491 		goto out_alloc_wqs;
3492 	}
3493 
3494 	rc = smc_llc_init();
3495 	if (rc) {
3496 		pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3497 		goto out_core;
3498 	}
3499 
3500 	rc = smc_cdc_init();
3501 	if (rc) {
3502 		pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3503 		goto out_core;
3504 	}
3505 
3506 	rc = proto_register(&smc_proto, 1);
3507 	if (rc) {
3508 		pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3509 		goto out_core;
3510 	}
3511 
3512 	rc = proto_register(&smc_proto6, 1);
3513 	if (rc) {
3514 		pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3515 		goto out_proto;
3516 	}
3517 
3518 	rc = sock_register(&smc_sock_family_ops);
3519 	if (rc) {
3520 		pr_err("%s: sock_register fails with %d\n", __func__, rc);
3521 		goto out_proto6;
3522 	}
3523 	INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3524 	INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3525 
3526 	rc = smc_ib_register_client();
3527 	if (rc) {
3528 		pr_err("%s: ib_register fails with %d\n", __func__, rc);
3529 		goto out_sock;
3530 	}
3531 
3532 	rc = tcp_register_ulp(&smc_ulp_ops);
3533 	if (rc) {
3534 		pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3535 		goto out_ib;
3536 	}
3537 
3538 	static_branch_enable(&tcp_have_smc);
3539 	return 0;
3540 
3541 out_ib:
3542 	smc_ib_unregister_client();
3543 out_sock:
3544 	sock_unregister(PF_SMC);
3545 out_proto6:
3546 	proto_unregister(&smc_proto6);
3547 out_proto:
3548 	proto_unregister(&smc_proto);
3549 out_core:
3550 	smc_core_exit();
3551 out_alloc_wqs:
3552 	destroy_workqueue(smc_close_wq);
3553 out_alloc_hs_wq:
3554 	destroy_workqueue(smc_hs_wq);
3555 out_alloc_tcp_ls_wq:
3556 	destroy_workqueue(smc_tcp_ls_wq);
3557 out_pnet:
3558 	smc_pnet_exit();
3559 out_nl:
3560 	smc_nl_exit();
3561 out_ism:
3562 	smc_clc_exit();
3563 	smc_ism_exit();
3564 out_pernet_subsys_stat:
3565 	unregister_pernet_subsys(&smc_net_stat_ops);
3566 out_pernet_subsys:
3567 	unregister_pernet_subsys(&smc_net_ops);
3568 
3569 	return rc;
3570 }
3571 
3572 static void __exit smc_exit(void)
3573 {
3574 	static_branch_disable(&tcp_have_smc);
3575 	tcp_unregister_ulp(&smc_ulp_ops);
3576 	sock_unregister(PF_SMC);
3577 	smc_core_exit();
3578 	smc_ib_unregister_client();
3579 	smc_ism_exit();
3580 	destroy_workqueue(smc_close_wq);
3581 	destroy_workqueue(smc_tcp_ls_wq);
3582 	destroy_workqueue(smc_hs_wq);
3583 	proto_unregister(&smc_proto6);
3584 	proto_unregister(&smc_proto);
3585 	smc_pnet_exit();
3586 	smc_nl_exit();
3587 	smc_clc_exit();
3588 	unregister_pernet_subsys(&smc_net_stat_ops);
3589 	unregister_pernet_subsys(&smc_net_ops);
3590 	rcu_barrier();
3591 }
3592 
3593 module_init(smc_init);
3594 module_exit(smc_exit);
3595 
3596 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3597 MODULE_DESCRIPTION("smc socket address family");
3598 MODULE_LICENSE("GPL");
3599 MODULE_ALIAS_NETPROTO(PF_SMC);
3600 MODULE_ALIAS_TCP_ULP("smc");
3601 MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);
3602