xref: /linux/net/smc/af_smc.c (revision 95444b9eeb8c5c0330563931d70c61ca3b101548)
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 #include "smc_loopback.h"
57 
58 static DEFINE_MUTEX(smc_server_lgr_pending);	/* serialize link group
59 						 * creation on server
60 						 */
61 static DEFINE_MUTEX(smc_client_lgr_pending);	/* serialize link group
62 						 * creation on client
63 						 */
64 
65 static struct workqueue_struct	*smc_tcp_ls_wq;	/* wq for tcp listen work */
66 struct workqueue_struct	*smc_hs_wq;	/* wq for handshake work */
67 struct workqueue_struct	*smc_close_wq;	/* wq for close work */
68 
69 static void smc_tcp_listen_work(struct work_struct *);
70 static void smc_connect_work(struct work_struct *);
71 
72 int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb)
73 {
74 	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
75 	void *hdr;
76 
77 	if (cb_ctx->pos[0])
78 		goto out;
79 
80 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
81 			  &smc_gen_nl_family, NLM_F_MULTI,
82 			  SMC_NETLINK_DUMP_HS_LIMITATION);
83 	if (!hdr)
84 		return -ENOMEM;
85 
86 	if (nla_put_u8(skb, SMC_NLA_HS_LIMITATION_ENABLED,
87 		       sock_net(skb->sk)->smc.limit_smc_hs))
88 		goto err;
89 
90 	genlmsg_end(skb, hdr);
91 	cb_ctx->pos[0] = 1;
92 out:
93 	return skb->len;
94 err:
95 	genlmsg_cancel(skb, hdr);
96 	return -EMSGSIZE;
97 }
98 
99 int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
100 {
101 	sock_net(skb->sk)->smc.limit_smc_hs = true;
102 	return 0;
103 }
104 
105 int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
106 {
107 	sock_net(skb->sk)->smc.limit_smc_hs = false;
108 	return 0;
109 }
110 
111 static void smc_set_keepalive(struct sock *sk, int val)
112 {
113 	struct smc_sock *smc = smc_sk(sk);
114 
115 	smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
116 }
117 
118 static struct sock *smc_tcp_syn_recv_sock(const struct sock *sk,
119 					  struct sk_buff *skb,
120 					  struct request_sock *req,
121 					  struct dst_entry *dst,
122 					  struct request_sock *req_unhash,
123 					  bool *own_req)
124 {
125 	struct smc_sock *smc;
126 	struct sock *child;
127 
128 	smc = smc_clcsock_user_data(sk);
129 
130 	if (READ_ONCE(sk->sk_ack_backlog) + atomic_read(&smc->queued_smc_hs) >
131 				sk->sk_max_ack_backlog)
132 		goto drop;
133 
134 	if (sk_acceptq_is_full(&smc->sk)) {
135 		NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
136 		goto drop;
137 	}
138 
139 	/* passthrough to original syn recv sock fct */
140 	child = smc->ori_af_ops->syn_recv_sock(sk, skb, req, dst, req_unhash,
141 					       own_req);
142 	/* child must not inherit smc or its ops */
143 	if (child) {
144 		rcu_assign_sk_user_data(child, NULL);
145 
146 		/* v4-mapped sockets don't inherit parent ops. Don't restore. */
147 		if (inet_csk(child)->icsk_af_ops == inet_csk(sk)->icsk_af_ops)
148 			inet_csk(child)->icsk_af_ops = smc->ori_af_ops;
149 	}
150 	return child;
151 
152 drop:
153 	dst_release(dst);
154 	tcp_listendrop(sk);
155 	return NULL;
156 }
157 
158 static bool smc_hs_congested(const struct sock *sk)
159 {
160 	const struct smc_sock *smc;
161 
162 	smc = smc_clcsock_user_data(sk);
163 
164 	if (!smc)
165 		return true;
166 
167 	if (workqueue_congested(WORK_CPU_UNBOUND, smc_hs_wq))
168 		return true;
169 
170 	return false;
171 }
172 
173 static struct smc_hashinfo smc_v4_hashinfo = {
174 	.lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
175 };
176 
177 static struct smc_hashinfo smc_v6_hashinfo = {
178 	.lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
179 };
180 
181 static int smc_hash_sk(struct sock *sk)
182 {
183 	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
184 	struct hlist_head *head;
185 
186 	head = &h->ht;
187 
188 	write_lock_bh(&h->lock);
189 	sk_add_node(sk, head);
190 	write_unlock_bh(&h->lock);
191 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
192 
193 	return 0;
194 }
195 
196 static 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 
206 /* This will be called before user really release sock_lock. So do the
207  * work which we didn't do because of user hold the sock_lock in the
208  * BH context
209  */
210 static void smc_release_cb(struct sock *sk)
211 {
212 	struct smc_sock *smc = smc_sk(sk);
213 
214 	if (smc->conn.tx_in_release_sock) {
215 		smc_tx_pending(&smc->conn);
216 		smc->conn.tx_in_release_sock = false;
217 	}
218 }
219 
220 struct proto smc_proto = {
221 	.name		= "SMC",
222 	.owner		= THIS_MODULE,
223 	.keepalive	= smc_set_keepalive,
224 	.hash		= smc_hash_sk,
225 	.unhash		= smc_unhash_sk,
226 	.release_cb	= smc_release_cb,
227 	.obj_size	= sizeof(struct smc_sock),
228 	.h.smc_hash	= &smc_v4_hashinfo,
229 	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
230 };
231 EXPORT_SYMBOL_GPL(smc_proto);
232 
233 struct proto smc_proto6 = {
234 	.name		= "SMC6",
235 	.owner		= THIS_MODULE,
236 	.keepalive	= smc_set_keepalive,
237 	.hash		= smc_hash_sk,
238 	.unhash		= smc_unhash_sk,
239 	.release_cb	= smc_release_cb,
240 	.obj_size	= sizeof(struct smc_sock),
241 	.h.smc_hash	= &smc_v6_hashinfo,
242 	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
243 };
244 EXPORT_SYMBOL_GPL(smc_proto6);
245 
246 static void smc_fback_restore_callbacks(struct smc_sock *smc)
247 {
248 	struct sock *clcsk = smc->clcsock->sk;
249 
250 	write_lock_bh(&clcsk->sk_callback_lock);
251 	clcsk->sk_user_data = NULL;
252 
253 	smc_clcsock_restore_cb(&clcsk->sk_state_change, &smc->clcsk_state_change);
254 	smc_clcsock_restore_cb(&clcsk->sk_data_ready, &smc->clcsk_data_ready);
255 	smc_clcsock_restore_cb(&clcsk->sk_write_space, &smc->clcsk_write_space);
256 	smc_clcsock_restore_cb(&clcsk->sk_error_report, &smc->clcsk_error_report);
257 
258 	write_unlock_bh(&clcsk->sk_callback_lock);
259 }
260 
261 static void smc_restore_fallback_changes(struct smc_sock *smc)
262 {
263 	if (smc->clcsock->file) { /* non-accepted sockets have no file yet */
264 		smc->clcsock->file->private_data = smc->sk.sk_socket;
265 		smc->clcsock->file = NULL;
266 		smc_fback_restore_callbacks(smc);
267 	}
268 }
269 
270 static int __smc_release(struct smc_sock *smc)
271 {
272 	struct sock *sk = &smc->sk;
273 	int rc = 0;
274 
275 	if (!smc->use_fallback) {
276 		rc = smc_close_active(smc);
277 		smc_sock_set_flag(sk, SOCK_DEAD);
278 		sk->sk_shutdown |= SHUTDOWN_MASK;
279 	} else {
280 		if (sk->sk_state != SMC_CLOSED) {
281 			if (sk->sk_state != SMC_LISTEN &&
282 			    sk->sk_state != SMC_INIT)
283 				sock_put(sk); /* passive closing */
284 			if (sk->sk_state == SMC_LISTEN) {
285 				/* wake up clcsock accept */
286 				rc = kernel_sock_shutdown(smc->clcsock,
287 							  SHUT_RDWR);
288 			}
289 			sk->sk_state = SMC_CLOSED;
290 			sk->sk_state_change(sk);
291 		}
292 		smc_restore_fallback_changes(smc);
293 	}
294 
295 	sk->sk_prot->unhash(sk);
296 
297 	if (sk->sk_state == SMC_CLOSED) {
298 		if (smc->clcsock) {
299 			release_sock(sk);
300 			smc_clcsock_release(smc);
301 			lock_sock(sk);
302 		}
303 		if (!smc->use_fallback)
304 			smc_conn_free(&smc->conn);
305 	}
306 
307 	return rc;
308 }
309 
310 static int smc_release(struct socket *sock)
311 {
312 	struct sock *sk = sock->sk;
313 	struct smc_sock *smc;
314 	int old_state, rc = 0;
315 
316 	if (!sk)
317 		goto out;
318 
319 	sock_hold(sk); /* sock_put below */
320 	smc = smc_sk(sk);
321 
322 	old_state = sk->sk_state;
323 
324 	/* cleanup for a dangling non-blocking connect */
325 	if (smc->connect_nonblock && old_state == SMC_INIT)
326 		tcp_abort(smc->clcsock->sk, ECONNABORTED);
327 
328 	if (cancel_work_sync(&smc->connect_work))
329 		sock_put(&smc->sk); /* sock_hold in smc_connect for passive closing */
330 
331 	if (sk->sk_state == SMC_LISTEN)
332 		/* smc_close_non_accepted() is called and acquires
333 		 * sock lock for child sockets again
334 		 */
335 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
336 	else
337 		lock_sock(sk);
338 
339 	if (old_state == SMC_INIT && sk->sk_state == SMC_ACTIVE &&
340 	    !smc->use_fallback)
341 		smc_close_active_abort(smc);
342 
343 	rc = __smc_release(smc);
344 
345 	/* detach socket */
346 	sock_orphan(sk);
347 	sock->sk = NULL;
348 	release_sock(sk);
349 
350 	sock_put(sk); /* sock_hold above */
351 	sock_put(sk); /* final sock_put */
352 out:
353 	return rc;
354 }
355 
356 static void smc_destruct(struct sock *sk)
357 {
358 	if (sk->sk_state != SMC_CLOSED)
359 		return;
360 	if (!sock_flag(sk, SOCK_DEAD))
361 		return;
362 }
363 
364 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
365 				   int protocol)
366 {
367 	struct smc_sock *smc;
368 	struct proto *prot;
369 	struct sock *sk;
370 
371 	prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
372 	sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
373 	if (!sk)
374 		return NULL;
375 
376 	sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
377 	sk->sk_state = SMC_INIT;
378 	sk->sk_destruct = smc_destruct;
379 	sk->sk_protocol = protocol;
380 	WRITE_ONCE(sk->sk_sndbuf, 2 * READ_ONCE(net->smc.sysctl_wmem));
381 	WRITE_ONCE(sk->sk_rcvbuf, 2 * READ_ONCE(net->smc.sysctl_rmem));
382 	smc = smc_sk(sk);
383 	INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
384 	INIT_WORK(&smc->connect_work, smc_connect_work);
385 	INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
386 	INIT_LIST_HEAD(&smc->accept_q);
387 	spin_lock_init(&smc->accept_q_lock);
388 	spin_lock_init(&smc->conn.send_lock);
389 	sk->sk_prot->hash(sk);
390 	mutex_init(&smc->clcsock_release_lock);
391 	smc_init_saved_callbacks(smc);
392 
393 	return sk;
394 }
395 
396 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
397 		    int addr_len)
398 {
399 	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
400 	struct sock *sk = sock->sk;
401 	struct smc_sock *smc;
402 	int rc;
403 
404 	smc = smc_sk(sk);
405 
406 	/* replicate tests from inet_bind(), to be safe wrt. future changes */
407 	rc = -EINVAL;
408 	if (addr_len < sizeof(struct sockaddr_in))
409 		goto out;
410 
411 	rc = -EAFNOSUPPORT;
412 	if (addr->sin_family != AF_INET &&
413 	    addr->sin_family != AF_INET6 &&
414 	    addr->sin_family != AF_UNSPEC)
415 		goto out;
416 	/* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
417 	if (addr->sin_family == AF_UNSPEC &&
418 	    addr->sin_addr.s_addr != htonl(INADDR_ANY))
419 		goto out;
420 
421 	lock_sock(sk);
422 
423 	/* Check if socket is already active */
424 	rc = -EINVAL;
425 	if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
426 		goto out_rel;
427 
428 	smc->clcsock->sk->sk_reuse = sk->sk_reuse;
429 	smc->clcsock->sk->sk_reuseport = sk->sk_reuseport;
430 	rc = kernel_bind(smc->clcsock, uaddr, addr_len);
431 
432 out_rel:
433 	release_sock(sk);
434 out:
435 	return rc;
436 }
437 
438 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
439  * clc socket (since smc is not called for these options from net/core)
440  */
441 
442 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
443 			     (1UL << SOCK_KEEPOPEN) | \
444 			     (1UL << SOCK_LINGER) | \
445 			     (1UL << SOCK_BROADCAST) | \
446 			     (1UL << SOCK_TIMESTAMP) | \
447 			     (1UL << SOCK_DBG) | \
448 			     (1UL << SOCK_RCVTSTAMP) | \
449 			     (1UL << SOCK_RCVTSTAMPNS) | \
450 			     (1UL << SOCK_LOCALROUTE) | \
451 			     (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
452 			     (1UL << SOCK_RXQ_OVFL) | \
453 			     (1UL << SOCK_WIFI_STATUS) | \
454 			     (1UL << SOCK_NOFCS) | \
455 			     (1UL << SOCK_FILTER_LOCKED) | \
456 			     (1UL << SOCK_TSTAMP_NEW))
457 
458 /* if set, use value set by setsockopt() - else use IPv4 or SMC sysctl value */
459 static void smc_adjust_sock_bufsizes(struct sock *nsk, struct sock *osk,
460 				     unsigned long mask)
461 {
462 	struct net *nnet = sock_net(nsk);
463 
464 	nsk->sk_userlocks = osk->sk_userlocks;
465 	if (osk->sk_userlocks & SOCK_SNDBUF_LOCK) {
466 		nsk->sk_sndbuf = osk->sk_sndbuf;
467 	} else {
468 		if (mask == SK_FLAGS_SMC_TO_CLC)
469 			WRITE_ONCE(nsk->sk_sndbuf,
470 				   READ_ONCE(nnet->ipv4.sysctl_tcp_wmem[1]));
471 		else
472 			WRITE_ONCE(nsk->sk_sndbuf,
473 				   2 * READ_ONCE(nnet->smc.sysctl_wmem));
474 	}
475 	if (osk->sk_userlocks & SOCK_RCVBUF_LOCK) {
476 		nsk->sk_rcvbuf = osk->sk_rcvbuf;
477 	} else {
478 		if (mask == SK_FLAGS_SMC_TO_CLC)
479 			WRITE_ONCE(nsk->sk_rcvbuf,
480 				   READ_ONCE(nnet->ipv4.sysctl_tcp_rmem[1]));
481 		else
482 			WRITE_ONCE(nsk->sk_rcvbuf,
483 				   2 * READ_ONCE(nnet->smc.sysctl_rmem));
484 	}
485 }
486 
487 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
488 				   unsigned long mask)
489 {
490 	/* options we don't get control via setsockopt for */
491 	nsk->sk_type = osk->sk_type;
492 	nsk->sk_sndtimeo = osk->sk_sndtimeo;
493 	nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
494 	nsk->sk_mark = READ_ONCE(osk->sk_mark);
495 	nsk->sk_priority = READ_ONCE(osk->sk_priority);
496 	nsk->sk_rcvlowat = osk->sk_rcvlowat;
497 	nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
498 	nsk->sk_err = osk->sk_err;
499 
500 	nsk->sk_flags &= ~mask;
501 	nsk->sk_flags |= osk->sk_flags & mask;
502 
503 	smc_adjust_sock_bufsizes(nsk, osk, mask);
504 }
505 
506 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
507 {
508 	smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
509 }
510 
511 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
512 			     (1UL << SOCK_KEEPOPEN) | \
513 			     (1UL << SOCK_LINGER) | \
514 			     (1UL << SOCK_DBG))
515 /* copy only settings and flags relevant for smc from clc to smc socket */
516 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
517 {
518 	smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
519 }
520 
521 /* register the new vzalloced sndbuf on all links */
522 static int smcr_lgr_reg_sndbufs(struct smc_link *link,
523 				struct smc_buf_desc *snd_desc)
524 {
525 	struct smc_link_group *lgr = link->lgr;
526 	int i, rc = 0;
527 
528 	if (!snd_desc->is_vm)
529 		return -EINVAL;
530 
531 	/* protect against parallel smcr_link_reg_buf() */
532 	down_write(&lgr->llc_conf_mutex);
533 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
534 		if (!smc_link_active(&lgr->lnk[i]))
535 			continue;
536 		rc = smcr_link_reg_buf(&lgr->lnk[i], snd_desc);
537 		if (rc)
538 			break;
539 	}
540 	up_write(&lgr->llc_conf_mutex);
541 	return rc;
542 }
543 
544 /* register the new rmb on all links */
545 static int smcr_lgr_reg_rmbs(struct smc_link *link,
546 			     struct smc_buf_desc *rmb_desc)
547 {
548 	struct smc_link_group *lgr = link->lgr;
549 	bool do_slow = false;
550 	int i, rc = 0;
551 
552 	rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
553 	if (rc)
554 		return rc;
555 
556 	down_read(&lgr->llc_conf_mutex);
557 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
558 		if (!smc_link_active(&lgr->lnk[i]))
559 			continue;
560 		if (!rmb_desc->is_reg_mr[link->link_idx]) {
561 			up_read(&lgr->llc_conf_mutex);
562 			goto slow_path;
563 		}
564 	}
565 	/* mr register already */
566 	goto fast_path;
567 slow_path:
568 	do_slow = true;
569 	/* protect against parallel smc_llc_cli_rkey_exchange() and
570 	 * parallel smcr_link_reg_buf()
571 	 */
572 	down_write(&lgr->llc_conf_mutex);
573 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
574 		if (!smc_link_active(&lgr->lnk[i]))
575 			continue;
576 		rc = smcr_link_reg_buf(&lgr->lnk[i], rmb_desc);
577 		if (rc)
578 			goto out;
579 	}
580 fast_path:
581 	/* exchange confirm_rkey msg with peer */
582 	rc = smc_llc_do_confirm_rkey(link, rmb_desc);
583 	if (rc) {
584 		rc = -EFAULT;
585 		goto out;
586 	}
587 	rmb_desc->is_conf_rkey = true;
588 out:
589 	do_slow ? up_write(&lgr->llc_conf_mutex) : up_read(&lgr->llc_conf_mutex);
590 	smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
591 	return rc;
592 }
593 
594 static int smcr_clnt_conf_first_link(struct smc_sock *smc)
595 {
596 	struct smc_link *link = smc->conn.lnk;
597 	struct smc_llc_qentry *qentry;
598 	int rc;
599 
600 	/* Receive CONFIRM LINK request from server over RoCE fabric.
601 	 * Increasing the client's timeout by twice as much as the server's
602 	 * timeout by default can temporarily avoid decline messages of
603 	 * both sides crossing or colliding
604 	 */
605 	qentry = smc_llc_wait(link->lgr, NULL, 2 * SMC_LLC_WAIT_TIME,
606 			      SMC_LLC_CONFIRM_LINK);
607 	if (!qentry) {
608 		struct smc_clc_msg_decline dclc;
609 
610 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
611 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
612 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
613 	}
614 	smc_llc_save_peer_uid(qentry);
615 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
616 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
617 	if (rc)
618 		return SMC_CLC_DECL_RMBE_EC;
619 
620 	rc = smc_ib_modify_qp_rts(link);
621 	if (rc)
622 		return SMC_CLC_DECL_ERR_RDYLNK;
623 
624 	smc_wr_remember_qp_attr(link);
625 
626 	/* reg the sndbuf if it was vzalloced */
627 	if (smc->conn.sndbuf_desc->is_vm) {
628 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
629 			return SMC_CLC_DECL_ERR_REGBUF;
630 	}
631 
632 	/* reg the rmb */
633 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
634 		return SMC_CLC_DECL_ERR_REGBUF;
635 
636 	/* confirm_rkey is implicit on 1st contact */
637 	smc->conn.rmb_desc->is_conf_rkey = true;
638 
639 	/* send CONFIRM LINK response over RoCE fabric */
640 	rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
641 	if (rc < 0)
642 		return SMC_CLC_DECL_TIMEOUT_CL;
643 
644 	smc_llc_link_active(link);
645 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
646 
647 	if (link->lgr->max_links > 1) {
648 		/* optional 2nd link, receive ADD LINK request from server */
649 		qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
650 				      SMC_LLC_ADD_LINK);
651 		if (!qentry) {
652 			struct smc_clc_msg_decline dclc;
653 
654 			rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
655 					      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
656 			if (rc == -EAGAIN)
657 				rc = 0; /* no DECLINE received, go with one link */
658 			return rc;
659 		}
660 		smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
661 		smc_llc_cli_add_link(link, qentry);
662 	}
663 	return 0;
664 }
665 
666 static bool smc_isascii(char *hostname)
667 {
668 	int i;
669 
670 	for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
671 		if (!isascii(hostname[i]))
672 			return false;
673 	return true;
674 }
675 
676 static void smc_conn_save_peer_info_fce(struct smc_sock *smc,
677 					struct smc_clc_msg_accept_confirm *clc)
678 {
679 	struct smc_clc_first_contact_ext *fce;
680 	int clc_v2_len;
681 
682 	if (clc->hdr.version == SMC_V1 ||
683 	    !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
684 		return;
685 
686 	if (smc->conn.lgr->is_smcd) {
687 		memcpy(smc->conn.lgr->negotiated_eid, clc->d1.eid,
688 		       SMC_MAX_EID_LEN);
689 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm, d1);
690 	} else {
691 		memcpy(smc->conn.lgr->negotiated_eid, clc->r1.eid,
692 		       SMC_MAX_EID_LEN);
693 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm, r1);
694 	}
695 	fce = (struct smc_clc_first_contact_ext *)(((u8 *)clc) + clc_v2_len);
696 	smc->conn.lgr->peer_os = fce->os_type;
697 	smc->conn.lgr->peer_smc_release = fce->release;
698 	if (smc_isascii(fce->hostname))
699 		memcpy(smc->conn.lgr->peer_hostname, fce->hostname,
700 		       SMC_MAX_HOSTNAME_LEN);
701 }
702 
703 static void smcr_conn_save_peer_info(struct smc_sock *smc,
704 				     struct smc_clc_msg_accept_confirm *clc)
705 {
706 	int bufsize = smc_uncompress_bufsize(clc->r0.rmbe_size);
707 
708 	smc->conn.peer_rmbe_idx = clc->r0.rmbe_idx;
709 	smc->conn.local_tx_ctrl.token = ntohl(clc->r0.rmbe_alert_token);
710 	smc->conn.peer_rmbe_size = bufsize;
711 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
712 	smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
713 }
714 
715 static void smcd_conn_save_peer_info(struct smc_sock *smc,
716 				     struct smc_clc_msg_accept_confirm *clc)
717 {
718 	int bufsize = smc_uncompress_bufsize(clc->d0.dmbe_size);
719 
720 	smc->conn.peer_rmbe_idx = clc->d0.dmbe_idx;
721 	smc->conn.peer_token = ntohll(clc->d0.token);
722 	/* msg header takes up space in the buffer */
723 	smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
724 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
725 	smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
726 }
727 
728 static void smc_conn_save_peer_info(struct smc_sock *smc,
729 				    struct smc_clc_msg_accept_confirm *clc)
730 {
731 	if (smc->conn.lgr->is_smcd)
732 		smcd_conn_save_peer_info(smc, clc);
733 	else
734 		smcr_conn_save_peer_info(smc, clc);
735 	smc_conn_save_peer_info_fce(smc, clc);
736 }
737 
738 static void smc_link_save_peer_info(struct smc_link *link,
739 				    struct smc_clc_msg_accept_confirm *clc,
740 				    struct smc_init_info *ini)
741 {
742 	link->peer_qpn = ntoh24(clc->r0.qpn);
743 	memcpy(link->peer_gid, ini->peer_gid, SMC_GID_SIZE);
744 	memcpy(link->peer_mac, ini->peer_mac, sizeof(link->peer_mac));
745 	link->peer_psn = ntoh24(clc->r0.psn);
746 	link->peer_mtu = clc->r0.qp_mtu;
747 }
748 
749 static void smc_stat_inc_fback_rsn_cnt(struct smc_sock *smc,
750 				       struct smc_stats_fback *fback_arr)
751 {
752 	int cnt;
753 
754 	for (cnt = 0; cnt < SMC_MAX_FBACK_RSN_CNT; cnt++) {
755 		if (fback_arr[cnt].fback_code == smc->fallback_rsn) {
756 			fback_arr[cnt].count++;
757 			break;
758 		}
759 		if (!fback_arr[cnt].fback_code) {
760 			fback_arr[cnt].fback_code = smc->fallback_rsn;
761 			fback_arr[cnt].count++;
762 			break;
763 		}
764 	}
765 }
766 
767 static void smc_stat_fallback(struct smc_sock *smc)
768 {
769 	struct net *net = sock_net(&smc->sk);
770 
771 	mutex_lock(&net->smc.mutex_fback_rsn);
772 	if (smc->listen_smc) {
773 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->srv);
774 		net->smc.fback_rsn->srv_fback_cnt++;
775 	} else {
776 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->clnt);
777 		net->smc.fback_rsn->clnt_fback_cnt++;
778 	}
779 	mutex_unlock(&net->smc.mutex_fback_rsn);
780 }
781 
782 /* must be called under rcu read lock */
783 static void smc_fback_wakeup_waitqueue(struct smc_sock *smc, void *key)
784 {
785 	struct socket_wq *wq;
786 	__poll_t flags;
787 
788 	wq = rcu_dereference(smc->sk.sk_wq);
789 	if (!skwq_has_sleeper(wq))
790 		return;
791 
792 	/* wake up smc sk->sk_wq */
793 	if (!key) {
794 		/* sk_state_change */
795 		wake_up_interruptible_all(&wq->wait);
796 	} else {
797 		flags = key_to_poll(key);
798 		if (flags & (EPOLLIN | EPOLLOUT))
799 			/* sk_data_ready or sk_write_space */
800 			wake_up_interruptible_sync_poll(&wq->wait, flags);
801 		else if (flags & EPOLLERR)
802 			/* sk_error_report */
803 			wake_up_interruptible_poll(&wq->wait, flags);
804 	}
805 }
806 
807 static int smc_fback_mark_woken(wait_queue_entry_t *wait,
808 				unsigned int mode, int sync, void *key)
809 {
810 	struct smc_mark_woken *mark =
811 		container_of(wait, struct smc_mark_woken, wait_entry);
812 
813 	mark->woken = true;
814 	mark->key = key;
815 	return 0;
816 }
817 
818 static void smc_fback_forward_wakeup(struct smc_sock *smc, struct sock *clcsk,
819 				     void (*clcsock_callback)(struct sock *sk))
820 {
821 	struct smc_mark_woken mark = { .woken = false };
822 	struct socket_wq *wq;
823 
824 	init_waitqueue_func_entry(&mark.wait_entry,
825 				  smc_fback_mark_woken);
826 	rcu_read_lock();
827 	wq = rcu_dereference(clcsk->sk_wq);
828 	if (!wq)
829 		goto out;
830 	add_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
831 	clcsock_callback(clcsk);
832 	remove_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
833 
834 	if (mark.woken)
835 		smc_fback_wakeup_waitqueue(smc, mark.key);
836 out:
837 	rcu_read_unlock();
838 }
839 
840 static void smc_fback_state_change(struct sock *clcsk)
841 {
842 	struct smc_sock *smc;
843 
844 	read_lock_bh(&clcsk->sk_callback_lock);
845 	smc = smc_clcsock_user_data(clcsk);
846 	if (smc)
847 		smc_fback_forward_wakeup(smc, clcsk,
848 					 smc->clcsk_state_change);
849 	read_unlock_bh(&clcsk->sk_callback_lock);
850 }
851 
852 static void smc_fback_data_ready(struct sock *clcsk)
853 {
854 	struct smc_sock *smc;
855 
856 	read_lock_bh(&clcsk->sk_callback_lock);
857 	smc = smc_clcsock_user_data(clcsk);
858 	if (smc)
859 		smc_fback_forward_wakeup(smc, clcsk,
860 					 smc->clcsk_data_ready);
861 	read_unlock_bh(&clcsk->sk_callback_lock);
862 }
863 
864 static void smc_fback_write_space(struct sock *clcsk)
865 {
866 	struct smc_sock *smc;
867 
868 	read_lock_bh(&clcsk->sk_callback_lock);
869 	smc = smc_clcsock_user_data(clcsk);
870 	if (smc)
871 		smc_fback_forward_wakeup(smc, clcsk,
872 					 smc->clcsk_write_space);
873 	read_unlock_bh(&clcsk->sk_callback_lock);
874 }
875 
876 static void smc_fback_error_report(struct sock *clcsk)
877 {
878 	struct smc_sock *smc;
879 
880 	read_lock_bh(&clcsk->sk_callback_lock);
881 	smc = smc_clcsock_user_data(clcsk);
882 	if (smc)
883 		smc_fback_forward_wakeup(smc, clcsk,
884 					 smc->clcsk_error_report);
885 	read_unlock_bh(&clcsk->sk_callback_lock);
886 }
887 
888 static void smc_fback_replace_callbacks(struct smc_sock *smc)
889 {
890 	struct sock *clcsk = smc->clcsock->sk;
891 
892 	write_lock_bh(&clcsk->sk_callback_lock);
893 	clcsk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
894 
895 	smc_clcsock_replace_cb(&clcsk->sk_state_change, smc_fback_state_change,
896 			       &smc->clcsk_state_change);
897 	smc_clcsock_replace_cb(&clcsk->sk_data_ready, smc_fback_data_ready,
898 			       &smc->clcsk_data_ready);
899 	smc_clcsock_replace_cb(&clcsk->sk_write_space, smc_fback_write_space,
900 			       &smc->clcsk_write_space);
901 	smc_clcsock_replace_cb(&clcsk->sk_error_report, smc_fback_error_report,
902 			       &smc->clcsk_error_report);
903 
904 	write_unlock_bh(&clcsk->sk_callback_lock);
905 }
906 
907 static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code)
908 {
909 	int rc = 0;
910 
911 	mutex_lock(&smc->clcsock_release_lock);
912 	if (!smc->clcsock) {
913 		rc = -EBADF;
914 		goto out;
915 	}
916 
917 	smc->use_fallback = true;
918 	smc->fallback_rsn = reason_code;
919 	smc_stat_fallback(smc);
920 	trace_smc_switch_to_fallback(smc, reason_code);
921 	if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
922 		smc->clcsock->file = smc->sk.sk_socket->file;
923 		smc->clcsock->file->private_data = smc->clcsock;
924 		smc->clcsock->wq.fasync_list =
925 			smc->sk.sk_socket->wq.fasync_list;
926 		smc->sk.sk_socket->wq.fasync_list = NULL;
927 
928 		/* There might be some wait entries remaining
929 		 * in smc sk->sk_wq and they should be woken up
930 		 * as clcsock's wait queue is woken up.
931 		 */
932 		smc_fback_replace_callbacks(smc);
933 	}
934 out:
935 	mutex_unlock(&smc->clcsock_release_lock);
936 	return rc;
937 }
938 
939 /* fall back during connect */
940 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
941 {
942 	struct net *net = sock_net(&smc->sk);
943 	int rc = 0;
944 
945 	rc = smc_switch_to_fallback(smc, reason_code);
946 	if (rc) { /* fallback fails */
947 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
948 		if (smc->sk.sk_state == SMC_INIT)
949 			sock_put(&smc->sk); /* passive closing */
950 		return rc;
951 	}
952 	smc_copy_sock_settings_to_clc(smc);
953 	smc->connect_nonblock = 0;
954 	if (smc->sk.sk_state == SMC_INIT)
955 		smc->sk.sk_state = SMC_ACTIVE;
956 	return 0;
957 }
958 
959 /* decline and fall back during connect */
960 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
961 					u8 version)
962 {
963 	struct net *net = sock_net(&smc->sk);
964 	int rc;
965 
966 	if (reason_code < 0) { /* error, fallback is not possible */
967 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
968 		if (smc->sk.sk_state == SMC_INIT)
969 			sock_put(&smc->sk); /* passive closing */
970 		return reason_code;
971 	}
972 	if (reason_code != SMC_CLC_DECL_PEERDECL) {
973 		rc = smc_clc_send_decline(smc, reason_code, version);
974 		if (rc < 0) {
975 			this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
976 			if (smc->sk.sk_state == SMC_INIT)
977 				sock_put(&smc->sk); /* passive closing */
978 			return rc;
979 		}
980 	}
981 	return smc_connect_fallback(smc, reason_code);
982 }
983 
984 static void smc_conn_abort(struct smc_sock *smc, int local_first)
985 {
986 	struct smc_connection *conn = &smc->conn;
987 	struct smc_link_group *lgr = conn->lgr;
988 	bool lgr_valid = false;
989 
990 	if (smc_conn_lgr_valid(conn))
991 		lgr_valid = true;
992 
993 	smc_conn_free(conn);
994 	if (local_first && lgr_valid)
995 		smc_lgr_cleanup_early(lgr);
996 }
997 
998 /* check if there is a rdma device available for this connection. */
999 /* called for connect and listen */
1000 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
1001 {
1002 	/* PNET table look up: search active ib_device and port
1003 	 * within same PNETID that also contains the ethernet device
1004 	 * used for the internal TCP socket
1005 	 */
1006 	smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
1007 	if (!ini->check_smcrv2 && !ini->ib_dev)
1008 		return SMC_CLC_DECL_NOSMCRDEV;
1009 	if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
1010 		return SMC_CLC_DECL_NOSMCRDEV;
1011 	return 0;
1012 }
1013 
1014 /* check if there is an ISM device available for this connection. */
1015 /* called for connect and listen */
1016 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
1017 {
1018 	/* Find ISM device with same PNETID as connecting interface  */
1019 	smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
1020 	if (!ini->ism_dev[0])
1021 		return SMC_CLC_DECL_NOSMCDDEV;
1022 	else
1023 		ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
1024 	return 0;
1025 }
1026 
1027 /* is chid unique for the ism devices that are already determined? */
1028 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
1029 					   int cnt)
1030 {
1031 	int i = (!ini->ism_dev[0]) ? 1 : 0;
1032 
1033 	for (; i < cnt; i++)
1034 		if (ini->ism_chid[i] == chid)
1035 			return false;
1036 	return true;
1037 }
1038 
1039 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
1040  * PNETID matching net_device)
1041  */
1042 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
1043 				       struct smc_init_info *ini)
1044 {
1045 	int rc = SMC_CLC_DECL_NOSMCDDEV;
1046 	struct smcd_dev *smcd;
1047 	int i = 1, entry = 1;
1048 	bool is_emulated;
1049 	u16 chid;
1050 
1051 	if (smcd_indicated(ini->smc_type_v1))
1052 		rc = 0;		/* already initialized for V1 */
1053 	mutex_lock(&smcd_dev_list.mutex);
1054 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1055 		if (smcd->going_away || smcd == ini->ism_dev[0])
1056 			continue;
1057 		chid = smc_ism_get_chid(smcd);
1058 		if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
1059 			continue;
1060 		is_emulated = __smc_ism_is_emulated(chid);
1061 		if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
1062 		    smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
1063 			if (is_emulated && entry == SMCD_CLC_MAX_V2_GID_ENTRIES)
1064 				/* It's the last GID-CHID entry left in CLC
1065 				 * Proposal SMC-Dv2 extension, but an Emulated-
1066 				 * ISM device will take two entries. So give
1067 				 * up it and try the next potential ISM device.
1068 				 */
1069 				continue;
1070 			ini->ism_dev[i] = smcd;
1071 			ini->ism_chid[i] = chid;
1072 			ini->is_smcd = true;
1073 			rc = 0;
1074 			i++;
1075 			entry = is_emulated ? entry + 2 : entry + 1;
1076 			if (entry > SMCD_CLC_MAX_V2_GID_ENTRIES)
1077 				break;
1078 		}
1079 	}
1080 	mutex_unlock(&smcd_dev_list.mutex);
1081 	ini->ism_offered_cnt = i - 1;
1082 	if (!ini->ism_dev[0] && !ini->ism_dev[1])
1083 		ini->smcd_version = 0;
1084 
1085 	return rc;
1086 }
1087 
1088 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
1089 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
1090 				      struct smc_init_info *ini)
1091 {
1092 	if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
1093 		return SMC_CLC_DECL_ISMVLANERR;
1094 	return 0;
1095 }
1096 
1097 static int smc_find_proposal_devices(struct smc_sock *smc,
1098 				     struct smc_init_info *ini)
1099 {
1100 	int rc = 0;
1101 
1102 	/* check if there is an ism device available */
1103 	if (!(ini->smcd_version & SMC_V1) ||
1104 	    smc_find_ism_device(smc, ini) ||
1105 	    smc_connect_ism_vlan_setup(smc, ini))
1106 		ini->smcd_version &= ~SMC_V1;
1107 	/* else ISM V1 is supported for this connection */
1108 
1109 	/* check if there is an rdma device available */
1110 	if (!(ini->smcr_version & SMC_V1) ||
1111 	    smc_find_rdma_device(smc, ini))
1112 		ini->smcr_version &= ~SMC_V1;
1113 	/* else RDMA is supported for this connection */
1114 
1115 	ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
1116 					      ini->smcr_version & SMC_V1);
1117 
1118 	/* check if there is an ism v2 device available */
1119 	if (!(ini->smcd_version & SMC_V2) ||
1120 	    !smc_ism_is_v2_capable() ||
1121 	    smc_find_ism_v2_device_clnt(smc, ini))
1122 		ini->smcd_version &= ~SMC_V2;
1123 
1124 	/* check if there is an rdma v2 device available */
1125 	ini->check_smcrv2 = true;
1126 	ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
1127 	if (!(ini->smcr_version & SMC_V2) ||
1128 	    smc->clcsock->sk->sk_family != AF_INET ||
1129 	    !smc_clc_ueid_count() ||
1130 	    smc_find_rdma_device(smc, ini))
1131 		ini->smcr_version &= ~SMC_V2;
1132 	ini->check_smcrv2 = false;
1133 
1134 	ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
1135 					      ini->smcr_version & SMC_V2);
1136 
1137 	/* if neither ISM nor RDMA are supported, fallback */
1138 	if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
1139 		rc = SMC_CLC_DECL_NOSMCDEV;
1140 
1141 	return rc;
1142 }
1143 
1144 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
1145  * used, the VLAN ID will be registered again during the connection setup.
1146  */
1147 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
1148 					struct smc_init_info *ini)
1149 {
1150 	if (!smcd_indicated(ini->smc_type_v1))
1151 		return 0;
1152 	if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
1153 		return SMC_CLC_DECL_CNFERR;
1154 	return 0;
1155 }
1156 
1157 #define SMC_CLC_MAX_ACCEPT_LEN \
1158 	(sizeof(struct smc_clc_msg_accept_confirm) + \
1159 	 sizeof(struct smc_clc_first_contact_ext_v2x) + \
1160 	 sizeof(struct smc_clc_msg_trail))
1161 
1162 /* CLC handshake during connect */
1163 static int smc_connect_clc(struct smc_sock *smc,
1164 			   struct smc_clc_msg_accept_confirm *aclc,
1165 			   struct smc_init_info *ini)
1166 {
1167 	int rc = 0;
1168 
1169 	/* do inband token exchange */
1170 	rc = smc_clc_send_proposal(smc, ini);
1171 	if (rc)
1172 		return rc;
1173 	/* receive SMC Accept CLC message */
1174 	return smc_clc_wait_msg(smc, aclc, SMC_CLC_MAX_ACCEPT_LEN,
1175 				SMC_CLC_ACCEPT, CLC_WAIT_TIME);
1176 }
1177 
1178 void smc_fill_gid_list(struct smc_link_group *lgr,
1179 		       struct smc_gidlist *gidlist,
1180 		       struct smc_ib_device *known_dev, u8 *known_gid)
1181 {
1182 	struct smc_init_info *alt_ini = NULL;
1183 
1184 	memset(gidlist, 0, sizeof(*gidlist));
1185 	memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
1186 
1187 	alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
1188 	if (!alt_ini)
1189 		goto out;
1190 
1191 	alt_ini->vlan_id = lgr->vlan_id;
1192 	alt_ini->check_smcrv2 = true;
1193 	alt_ini->smcrv2.saddr = lgr->saddr;
1194 	smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
1195 
1196 	if (!alt_ini->smcrv2.ib_dev_v2)
1197 		goto out;
1198 
1199 	memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
1200 	       SMC_GID_SIZE);
1201 
1202 out:
1203 	kfree(alt_ini);
1204 }
1205 
1206 static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
1207 				       struct smc_clc_msg_accept_confirm *aclc,
1208 				       struct smc_init_info *ini)
1209 {
1210 	struct smc_clc_first_contact_ext *fce =
1211 		smc_get_clc_first_contact_ext(aclc, false);
1212 	struct net *net = sock_net(&smc->sk);
1213 	int rc;
1214 
1215 	if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1216 		return 0;
1217 
1218 	if (fce->v2_direct) {
1219 		memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1220 		ini->smcrv2.uses_gateway = false;
1221 	} else {
1222 		if (smc_ib_find_route(net, smc->clcsock->sk->sk_rcv_saddr,
1223 				      smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1224 				      ini->smcrv2.nexthop_mac,
1225 				      &ini->smcrv2.uses_gateway))
1226 			return SMC_CLC_DECL_NOROUTE;
1227 		if (!ini->smcrv2.uses_gateway) {
1228 			/* mismatch: peer claims indirect, but its direct */
1229 			return SMC_CLC_DECL_NOINDIRECT;
1230 		}
1231 	}
1232 
1233 	ini->release_nr = fce->release;
1234 	rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1235 	if (rc)
1236 		return rc;
1237 
1238 	return 0;
1239 }
1240 
1241 /* setup for RDMA connection of client */
1242 static int smc_connect_rdma(struct smc_sock *smc,
1243 			    struct smc_clc_msg_accept_confirm *aclc,
1244 			    struct smc_init_info *ini)
1245 {
1246 	int i, reason_code = 0;
1247 	struct smc_link *link;
1248 	u8 *eid = NULL;
1249 
1250 	ini->is_smcd = false;
1251 	ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1252 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1253 	memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1254 	memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1255 	memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1256 	ini->max_conns = SMC_CONN_PER_LGR_MAX;
1257 	ini->max_links = SMC_LINKS_ADD_LNK_MAX;
1258 
1259 	reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1260 	if (reason_code)
1261 		return reason_code;
1262 
1263 	mutex_lock(&smc_client_lgr_pending);
1264 	reason_code = smc_conn_create(smc, ini);
1265 	if (reason_code) {
1266 		mutex_unlock(&smc_client_lgr_pending);
1267 		return reason_code;
1268 	}
1269 
1270 	smc_conn_save_peer_info(smc, aclc);
1271 
1272 	if (ini->first_contact_local) {
1273 		link = smc->conn.lnk;
1274 	} else {
1275 		/* set link that was assigned by server */
1276 		link = NULL;
1277 		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1278 			struct smc_link *l = &smc->conn.lgr->lnk[i];
1279 
1280 			if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1281 			    !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1282 				    SMC_GID_SIZE) &&
1283 			    (aclc->hdr.version > SMC_V1 ||
1284 			     !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1285 				     sizeof(l->peer_mac)))) {
1286 				link = l;
1287 				break;
1288 			}
1289 		}
1290 		if (!link) {
1291 			reason_code = SMC_CLC_DECL_NOSRVLINK;
1292 			goto connect_abort;
1293 		}
1294 		smc_switch_link_and_count(&smc->conn, link);
1295 	}
1296 
1297 	/* create send buffer and rmb */
1298 	if (smc_buf_create(smc, false)) {
1299 		reason_code = SMC_CLC_DECL_MEM;
1300 		goto connect_abort;
1301 	}
1302 
1303 	if (ini->first_contact_local)
1304 		smc_link_save_peer_info(link, aclc, ini);
1305 
1306 	if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1307 		reason_code = SMC_CLC_DECL_ERR_RTOK;
1308 		goto connect_abort;
1309 	}
1310 
1311 	smc_close_init(smc);
1312 	smc_rx_init(smc);
1313 
1314 	if (ini->first_contact_local) {
1315 		if (smc_ib_ready_link(link)) {
1316 			reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1317 			goto connect_abort;
1318 		}
1319 	} else {
1320 		/* reg sendbufs if they were vzalloced */
1321 		if (smc->conn.sndbuf_desc->is_vm) {
1322 			if (smcr_lgr_reg_sndbufs(link, smc->conn.sndbuf_desc)) {
1323 				reason_code = SMC_CLC_DECL_ERR_REGBUF;
1324 				goto connect_abort;
1325 			}
1326 		}
1327 		if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1328 			reason_code = SMC_CLC_DECL_ERR_REGBUF;
1329 			goto connect_abort;
1330 		}
1331 	}
1332 
1333 	if (aclc->hdr.version > SMC_V1) {
1334 		eid = aclc->r1.eid;
1335 		if (ini->first_contact_local)
1336 			smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1337 					  link->smcibdev, link->gid);
1338 	}
1339 
1340 	reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1341 					   aclc->hdr.version, eid, ini);
1342 	if (reason_code)
1343 		goto connect_abort;
1344 
1345 	smc_tx_init(smc);
1346 
1347 	if (ini->first_contact_local) {
1348 		/* QP confirmation over RoCE fabric */
1349 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1350 		reason_code = smcr_clnt_conf_first_link(smc);
1351 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1352 		if (reason_code)
1353 			goto connect_abort;
1354 	}
1355 	mutex_unlock(&smc_client_lgr_pending);
1356 
1357 	smc_copy_sock_settings_to_clc(smc);
1358 	smc->connect_nonblock = 0;
1359 	if (smc->sk.sk_state == SMC_INIT)
1360 		smc->sk.sk_state = SMC_ACTIVE;
1361 
1362 	return 0;
1363 connect_abort:
1364 	smc_conn_abort(smc, ini->first_contact_local);
1365 	mutex_unlock(&smc_client_lgr_pending);
1366 	smc->connect_nonblock = 0;
1367 
1368 	return reason_code;
1369 }
1370 
1371 /* The server has chosen one of the proposed ISM devices for the communication.
1372  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1373  */
1374 static int
1375 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm *aclc,
1376 			       struct smc_init_info *ini)
1377 {
1378 	int i;
1379 
1380 	for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1381 		if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1382 			ini->ism_selected = i;
1383 			return 0;
1384 		}
1385 	}
1386 
1387 	return -EPROTO;
1388 }
1389 
1390 /* setup for ISM connection of client */
1391 static int smc_connect_ism(struct smc_sock *smc,
1392 			   struct smc_clc_msg_accept_confirm *aclc,
1393 			   struct smc_init_info *ini)
1394 {
1395 	u8 *eid = NULL;
1396 	int rc = 0;
1397 
1398 	ini->is_smcd = true;
1399 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1400 
1401 	if (aclc->hdr.version == SMC_V2) {
1402 		if (ini->first_contact_peer) {
1403 			struct smc_clc_first_contact_ext *fce =
1404 				smc_get_clc_first_contact_ext(aclc, true);
1405 
1406 			ini->release_nr = fce->release;
1407 			rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1408 			if (rc)
1409 				return rc;
1410 		}
1411 
1412 		rc = smc_v2_determine_accepted_chid(aclc, ini);
1413 		if (rc)
1414 			return rc;
1415 
1416 		if (__smc_ism_is_emulated(ini->ism_chid[ini->ism_selected]))
1417 			ini->ism_peer_gid[ini->ism_selected].gid_ext =
1418 						ntohll(aclc->d1.gid_ext);
1419 		/* for non-Emulated-ISM devices, peer gid_ext remains 0. */
1420 	}
1421 	ini->ism_peer_gid[ini->ism_selected].gid = ntohll(aclc->d0.gid);
1422 
1423 	/* there is only one lgr role for SMC-D; use server lock */
1424 	mutex_lock(&smc_server_lgr_pending);
1425 	rc = smc_conn_create(smc, ini);
1426 	if (rc) {
1427 		mutex_unlock(&smc_server_lgr_pending);
1428 		return rc;
1429 	}
1430 
1431 	/* Create send and receive buffers */
1432 	rc = smc_buf_create(smc, true);
1433 	if (rc) {
1434 		rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1435 		goto connect_abort;
1436 	}
1437 
1438 	smc_conn_save_peer_info(smc, aclc);
1439 
1440 	if (smc_ism_support_dmb_nocopy(smc->conn.lgr->smcd)) {
1441 		rc = smcd_buf_attach(smc);
1442 		if (rc) {
1443 			rc = SMC_CLC_DECL_MEM;	/* try to fallback */
1444 			goto connect_abort;
1445 		}
1446 	}
1447 	smc_close_init(smc);
1448 	smc_rx_init(smc);
1449 	smc_tx_init(smc);
1450 
1451 	if (aclc->hdr.version > SMC_V1)
1452 		eid = aclc->d1.eid;
1453 
1454 	rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1455 				  aclc->hdr.version, eid, ini);
1456 	if (rc)
1457 		goto connect_abort;
1458 	mutex_unlock(&smc_server_lgr_pending);
1459 
1460 	smc_copy_sock_settings_to_clc(smc);
1461 	smc->connect_nonblock = 0;
1462 	if (smc->sk.sk_state == SMC_INIT)
1463 		smc->sk.sk_state = SMC_ACTIVE;
1464 
1465 	return 0;
1466 connect_abort:
1467 	smc_conn_abort(smc, ini->first_contact_local);
1468 	mutex_unlock(&smc_server_lgr_pending);
1469 	smc->connect_nonblock = 0;
1470 
1471 	return rc;
1472 }
1473 
1474 /* check if received accept type and version matches a proposed one */
1475 static int smc_connect_check_aclc(struct smc_init_info *ini,
1476 				  struct smc_clc_msg_accept_confirm *aclc)
1477 {
1478 	if (aclc->hdr.typev1 != SMC_TYPE_R &&
1479 	    aclc->hdr.typev1 != SMC_TYPE_D)
1480 		return SMC_CLC_DECL_MODEUNSUPP;
1481 
1482 	if (aclc->hdr.version >= SMC_V2) {
1483 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1484 		     !smcr_indicated(ini->smc_type_v2)) ||
1485 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1486 		     !smcd_indicated(ini->smc_type_v2)))
1487 			return SMC_CLC_DECL_MODEUNSUPP;
1488 	} else {
1489 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1490 		     !smcr_indicated(ini->smc_type_v1)) ||
1491 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1492 		     !smcd_indicated(ini->smc_type_v1)))
1493 			return SMC_CLC_DECL_MODEUNSUPP;
1494 	}
1495 
1496 	return 0;
1497 }
1498 
1499 /* perform steps before actually connecting */
1500 static int __smc_connect(struct smc_sock *smc)
1501 {
1502 	u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1503 	struct smc_clc_msg_accept_confirm *aclc;
1504 	struct smc_init_info *ini = NULL;
1505 	u8 *buf = NULL;
1506 	int rc = 0;
1507 
1508 	if (smc->use_fallback)
1509 		return smc_connect_fallback(smc, smc->fallback_rsn);
1510 
1511 	/* if peer has not signalled SMC-capability, fall back */
1512 	if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1513 		return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1514 
1515 	/* IPSec connections opt out of SMC optimizations */
1516 	if (using_ipsec(smc))
1517 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1518 						    version);
1519 
1520 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1521 	if (!ini)
1522 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1523 						    version);
1524 
1525 	ini->smcd_version = SMC_V1 | SMC_V2;
1526 	ini->smcr_version = SMC_V1 | SMC_V2;
1527 	ini->smc_type_v1 = SMC_TYPE_B;
1528 	ini->smc_type_v2 = SMC_TYPE_B;
1529 
1530 	/* get vlan id from IP device */
1531 	if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1532 		ini->smcd_version &= ~SMC_V1;
1533 		ini->smcr_version = 0;
1534 		ini->smc_type_v1 = SMC_TYPE_N;
1535 		if (!ini->smcd_version) {
1536 			rc = SMC_CLC_DECL_GETVLANERR;
1537 			goto fallback;
1538 		}
1539 	}
1540 
1541 	rc = smc_find_proposal_devices(smc, ini);
1542 	if (rc)
1543 		goto fallback;
1544 
1545 	buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1546 	if (!buf) {
1547 		rc = SMC_CLC_DECL_MEM;
1548 		goto fallback;
1549 	}
1550 	aclc = (struct smc_clc_msg_accept_confirm *)buf;
1551 
1552 	/* perform CLC handshake */
1553 	rc = smc_connect_clc(smc, aclc, ini);
1554 	if (rc) {
1555 		/* -EAGAIN on timeout, see tcp_recvmsg() */
1556 		if (rc == -EAGAIN) {
1557 			rc = -ETIMEDOUT;
1558 			smc->sk.sk_err = ETIMEDOUT;
1559 		}
1560 		goto vlan_cleanup;
1561 	}
1562 
1563 	/* check if smc modes and versions of CLC proposal and accept match */
1564 	rc = smc_connect_check_aclc(ini, aclc);
1565 	version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1566 	if (rc)
1567 		goto vlan_cleanup;
1568 
1569 	/* depending on previous steps, connect using rdma or ism */
1570 	if (aclc->hdr.typev1 == SMC_TYPE_R) {
1571 		ini->smcr_version = version;
1572 		rc = smc_connect_rdma(smc, aclc, ini);
1573 	} else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1574 		ini->smcd_version = version;
1575 		rc = smc_connect_ism(smc, aclc, ini);
1576 	}
1577 	if (rc)
1578 		goto vlan_cleanup;
1579 
1580 	SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1581 	smc_connect_ism_vlan_cleanup(smc, ini);
1582 	kfree(buf);
1583 	kfree(ini);
1584 	return 0;
1585 
1586 vlan_cleanup:
1587 	smc_connect_ism_vlan_cleanup(smc, ini);
1588 	kfree(buf);
1589 fallback:
1590 	kfree(ini);
1591 	return smc_connect_decline_fallback(smc, rc, version);
1592 }
1593 
1594 static void smc_connect_work(struct work_struct *work)
1595 {
1596 	struct smc_sock *smc = container_of(work, struct smc_sock,
1597 					    connect_work);
1598 	long timeo = smc->sk.sk_sndtimeo;
1599 	int rc = 0;
1600 
1601 	if (!timeo)
1602 		timeo = MAX_SCHEDULE_TIMEOUT;
1603 	lock_sock(smc->clcsock->sk);
1604 	if (smc->clcsock->sk->sk_err) {
1605 		smc->sk.sk_err = smc->clcsock->sk->sk_err;
1606 	} else if ((1 << smc->clcsock->sk->sk_state) &
1607 					(TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1608 		rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1609 		if ((rc == -EPIPE) &&
1610 		    ((1 << smc->clcsock->sk->sk_state) &
1611 					(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1612 			rc = 0;
1613 	}
1614 	release_sock(smc->clcsock->sk);
1615 	lock_sock(&smc->sk);
1616 	if (rc != 0 || smc->sk.sk_err) {
1617 		smc->sk.sk_state = SMC_CLOSED;
1618 		if (rc == -EPIPE || rc == -EAGAIN)
1619 			smc->sk.sk_err = EPIPE;
1620 		else if (rc == -ECONNREFUSED)
1621 			smc->sk.sk_err = ECONNREFUSED;
1622 		else if (signal_pending(current))
1623 			smc->sk.sk_err = -sock_intr_errno(timeo);
1624 		sock_put(&smc->sk); /* passive closing */
1625 		goto out;
1626 	}
1627 
1628 	rc = __smc_connect(smc);
1629 	if (rc < 0)
1630 		smc->sk.sk_err = -rc;
1631 
1632 out:
1633 	if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1634 		if (smc->sk.sk_err) {
1635 			smc->sk.sk_state_change(&smc->sk);
1636 		} else { /* allow polling before and after fallback decision */
1637 			smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1638 			smc->sk.sk_write_space(&smc->sk);
1639 		}
1640 	}
1641 	release_sock(&smc->sk);
1642 }
1643 
1644 static int smc_connect(struct socket *sock, struct sockaddr *addr,
1645 		       int alen, int flags)
1646 {
1647 	struct sock *sk = sock->sk;
1648 	struct smc_sock *smc;
1649 	int rc = -EINVAL;
1650 
1651 	smc = smc_sk(sk);
1652 
1653 	/* separate smc parameter checking to be safe */
1654 	if (alen < sizeof(addr->sa_family))
1655 		goto out_err;
1656 	if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1657 		goto out_err;
1658 
1659 	lock_sock(sk);
1660 	switch (sock->state) {
1661 	default:
1662 		rc = -EINVAL;
1663 		goto out;
1664 	case SS_CONNECTED:
1665 		rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1666 		goto out;
1667 	case SS_CONNECTING:
1668 		if (sk->sk_state == SMC_ACTIVE)
1669 			goto connected;
1670 		break;
1671 	case SS_UNCONNECTED:
1672 		sock->state = SS_CONNECTING;
1673 		break;
1674 	}
1675 
1676 	switch (sk->sk_state) {
1677 	default:
1678 		goto out;
1679 	case SMC_CLOSED:
1680 		rc = sock_error(sk) ? : -ECONNABORTED;
1681 		sock->state = SS_UNCONNECTED;
1682 		goto out;
1683 	case SMC_ACTIVE:
1684 		rc = -EISCONN;
1685 		goto out;
1686 	case SMC_INIT:
1687 		break;
1688 	}
1689 
1690 	smc_copy_sock_settings_to_clc(smc);
1691 	tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1692 	if (smc->connect_nonblock) {
1693 		rc = -EALREADY;
1694 		goto out;
1695 	}
1696 	rc = kernel_connect(smc->clcsock, addr, alen, flags);
1697 	if (rc && rc != -EINPROGRESS)
1698 		goto out;
1699 
1700 	if (smc->use_fallback) {
1701 		sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1702 		goto out;
1703 	}
1704 	sock_hold(&smc->sk); /* sock put in passive closing */
1705 	if (flags & O_NONBLOCK) {
1706 		if (queue_work(smc_hs_wq, &smc->connect_work))
1707 			smc->connect_nonblock = 1;
1708 		rc = -EINPROGRESS;
1709 		goto out;
1710 	} else {
1711 		rc = __smc_connect(smc);
1712 		if (rc < 0)
1713 			goto out;
1714 	}
1715 
1716 connected:
1717 	rc = 0;
1718 	sock->state = SS_CONNECTED;
1719 out:
1720 	release_sock(sk);
1721 out_err:
1722 	return rc;
1723 }
1724 
1725 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1726 {
1727 	struct socket *new_clcsock = NULL;
1728 	struct sock *lsk = &lsmc->sk;
1729 	struct sock *new_sk;
1730 	int rc = -EINVAL;
1731 
1732 	release_sock(lsk);
1733 	new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1734 	if (!new_sk) {
1735 		rc = -ENOMEM;
1736 		lsk->sk_err = ENOMEM;
1737 		*new_smc = NULL;
1738 		lock_sock(lsk);
1739 		goto out;
1740 	}
1741 	*new_smc = smc_sk(new_sk);
1742 
1743 	mutex_lock(&lsmc->clcsock_release_lock);
1744 	if (lsmc->clcsock)
1745 		rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1746 	mutex_unlock(&lsmc->clcsock_release_lock);
1747 	lock_sock(lsk);
1748 	if  (rc < 0 && rc != -EAGAIN)
1749 		lsk->sk_err = -rc;
1750 	if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1751 		new_sk->sk_prot->unhash(new_sk);
1752 		if (new_clcsock)
1753 			sock_release(new_clcsock);
1754 		new_sk->sk_state = SMC_CLOSED;
1755 		smc_sock_set_flag(new_sk, SOCK_DEAD);
1756 		sock_put(new_sk); /* final */
1757 		*new_smc = NULL;
1758 		goto out;
1759 	}
1760 
1761 	/* new clcsock has inherited the smc listen-specific sk_data_ready
1762 	 * function; switch it back to the original sk_data_ready function
1763 	 */
1764 	new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1765 
1766 	/* if new clcsock has also inherited the fallback-specific callback
1767 	 * functions, switch them back to the original ones.
1768 	 */
1769 	if (lsmc->use_fallback) {
1770 		if (lsmc->clcsk_state_change)
1771 			new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1772 		if (lsmc->clcsk_write_space)
1773 			new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1774 		if (lsmc->clcsk_error_report)
1775 			new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1776 	}
1777 
1778 	(*new_smc)->clcsock = new_clcsock;
1779 out:
1780 	return rc;
1781 }
1782 
1783 /* add a just created sock to the accept queue of the listen sock as
1784  * candidate for a following socket accept call from user space
1785  */
1786 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1787 {
1788 	struct smc_sock *par = smc_sk(parent);
1789 
1790 	sock_hold(sk); /* sock_put in smc_accept_unlink () */
1791 	spin_lock(&par->accept_q_lock);
1792 	list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1793 	spin_unlock(&par->accept_q_lock);
1794 	sk_acceptq_added(parent);
1795 }
1796 
1797 /* remove a socket from the accept queue of its parental listening socket */
1798 static void smc_accept_unlink(struct sock *sk)
1799 {
1800 	struct smc_sock *par = smc_sk(sk)->listen_smc;
1801 
1802 	spin_lock(&par->accept_q_lock);
1803 	list_del_init(&smc_sk(sk)->accept_q);
1804 	spin_unlock(&par->accept_q_lock);
1805 	sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1806 	sock_put(sk); /* sock_hold in smc_accept_enqueue */
1807 }
1808 
1809 /* remove a sock from the accept queue to bind it to a new socket created
1810  * for a socket accept call from user space
1811  */
1812 struct sock *smc_accept_dequeue(struct sock *parent,
1813 				struct socket *new_sock)
1814 {
1815 	struct smc_sock *isk, *n;
1816 	struct sock *new_sk;
1817 
1818 	list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1819 		new_sk = (struct sock *)isk;
1820 
1821 		smc_accept_unlink(new_sk);
1822 		if (new_sk->sk_state == SMC_CLOSED) {
1823 			new_sk->sk_prot->unhash(new_sk);
1824 			if (isk->clcsock) {
1825 				sock_release(isk->clcsock);
1826 				isk->clcsock = NULL;
1827 			}
1828 			sock_put(new_sk); /* final */
1829 			continue;
1830 		}
1831 		if (new_sock) {
1832 			sock_graft(new_sk, new_sock);
1833 			new_sock->state = SS_CONNECTED;
1834 			if (isk->use_fallback) {
1835 				smc_sk(new_sk)->clcsock->file = new_sock->file;
1836 				isk->clcsock->file->private_data = isk->clcsock;
1837 			}
1838 		}
1839 		return new_sk;
1840 	}
1841 	return NULL;
1842 }
1843 
1844 /* clean up for a created but never accepted sock */
1845 void smc_close_non_accepted(struct sock *sk)
1846 {
1847 	struct smc_sock *smc = smc_sk(sk);
1848 
1849 	sock_hold(sk); /* sock_put below */
1850 	lock_sock(sk);
1851 	if (!sk->sk_lingertime)
1852 		/* wait for peer closing */
1853 		WRITE_ONCE(sk->sk_lingertime, SMC_MAX_STREAM_WAIT_TIMEOUT);
1854 	__smc_release(smc);
1855 	release_sock(sk);
1856 	sock_put(sk); /* sock_hold above */
1857 	sock_put(sk); /* final sock_put */
1858 }
1859 
1860 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1861 {
1862 	struct smc_link *link = smc->conn.lnk;
1863 	struct smc_llc_qentry *qentry;
1864 	int rc;
1865 
1866 	/* reg the sndbuf if it was vzalloced*/
1867 	if (smc->conn.sndbuf_desc->is_vm) {
1868 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
1869 			return SMC_CLC_DECL_ERR_REGBUF;
1870 	}
1871 
1872 	/* reg the rmb */
1873 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
1874 		return SMC_CLC_DECL_ERR_REGBUF;
1875 
1876 	/* send CONFIRM LINK request to client over the RoCE fabric */
1877 	rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1878 	if (rc < 0)
1879 		return SMC_CLC_DECL_TIMEOUT_CL;
1880 
1881 	/* receive CONFIRM LINK response from client over the RoCE fabric */
1882 	qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1883 			      SMC_LLC_CONFIRM_LINK);
1884 	if (!qentry) {
1885 		struct smc_clc_msg_decline dclc;
1886 
1887 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1888 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1889 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1890 	}
1891 	smc_llc_save_peer_uid(qentry);
1892 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1893 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1894 	if (rc)
1895 		return SMC_CLC_DECL_RMBE_EC;
1896 
1897 	/* confirm_rkey is implicit on 1st contact */
1898 	smc->conn.rmb_desc->is_conf_rkey = true;
1899 
1900 	smc_llc_link_active(link);
1901 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1902 
1903 	if (link->lgr->max_links > 1) {
1904 		down_write(&link->lgr->llc_conf_mutex);
1905 		/* initial contact - try to establish second link */
1906 		smc_llc_srv_add_link(link, NULL);
1907 		up_write(&link->lgr->llc_conf_mutex);
1908 	}
1909 	return 0;
1910 }
1911 
1912 /* listen worker: finish */
1913 static void smc_listen_out(struct smc_sock *new_smc)
1914 {
1915 	struct smc_sock *lsmc = new_smc->listen_smc;
1916 	struct sock *newsmcsk = &new_smc->sk;
1917 
1918 	if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1919 		atomic_dec(&lsmc->queued_smc_hs);
1920 
1921 	if (lsmc->sk.sk_state == SMC_LISTEN) {
1922 		lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1923 		smc_accept_enqueue(&lsmc->sk, newsmcsk);
1924 		release_sock(&lsmc->sk);
1925 	} else { /* no longer listening */
1926 		smc_close_non_accepted(newsmcsk);
1927 	}
1928 
1929 	/* Wake up accept */
1930 	lsmc->sk.sk_data_ready(&lsmc->sk);
1931 	sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1932 }
1933 
1934 /* listen worker: finish in state connected */
1935 static void smc_listen_out_connected(struct smc_sock *new_smc)
1936 {
1937 	struct sock *newsmcsk = &new_smc->sk;
1938 
1939 	if (newsmcsk->sk_state == SMC_INIT)
1940 		newsmcsk->sk_state = SMC_ACTIVE;
1941 
1942 	smc_listen_out(new_smc);
1943 }
1944 
1945 /* listen worker: finish in error state */
1946 static void smc_listen_out_err(struct smc_sock *new_smc)
1947 {
1948 	struct sock *newsmcsk = &new_smc->sk;
1949 	struct net *net = sock_net(newsmcsk);
1950 
1951 	this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1952 	if (newsmcsk->sk_state == SMC_INIT)
1953 		sock_put(&new_smc->sk); /* passive closing */
1954 	newsmcsk->sk_state = SMC_CLOSED;
1955 
1956 	smc_listen_out(new_smc);
1957 }
1958 
1959 /* listen worker: decline and fall back if possible */
1960 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1961 			       int local_first, u8 version)
1962 {
1963 	/* RDMA setup failed, switch back to TCP */
1964 	smc_conn_abort(new_smc, local_first);
1965 	if (reason_code < 0 ||
1966 	    smc_switch_to_fallback(new_smc, reason_code)) {
1967 		/* error, no fallback possible */
1968 		smc_listen_out_err(new_smc);
1969 		return;
1970 	}
1971 	if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1972 		if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1973 			smc_listen_out_err(new_smc);
1974 			return;
1975 		}
1976 	}
1977 	smc_listen_out_connected(new_smc);
1978 }
1979 
1980 /* listen worker: version checking */
1981 static int smc_listen_v2_check(struct smc_sock *new_smc,
1982 			       struct smc_clc_msg_proposal *pclc,
1983 			       struct smc_init_info *ini)
1984 {
1985 	struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1986 	struct smc_clc_v2_extension *pclc_v2_ext;
1987 	int rc = SMC_CLC_DECL_PEERNOSMC;
1988 
1989 	ini->smc_type_v1 = pclc->hdr.typev1;
1990 	ini->smc_type_v2 = pclc->hdr.typev2;
1991 	ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1992 	ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1993 	if (pclc->hdr.version > SMC_V1) {
1994 		if (smcd_indicated(ini->smc_type_v2))
1995 			ini->smcd_version |= SMC_V2;
1996 		if (smcr_indicated(ini->smc_type_v2))
1997 			ini->smcr_version |= SMC_V2;
1998 	}
1999 	if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
2000 		rc = SMC_CLC_DECL_PEERNOSMC;
2001 		goto out;
2002 	}
2003 	pclc_v2_ext = smc_get_clc_v2_ext(pclc);
2004 	if (!pclc_v2_ext) {
2005 		ini->smcd_version &= ~SMC_V2;
2006 		ini->smcr_version &= ~SMC_V2;
2007 		rc = SMC_CLC_DECL_NOV2EXT;
2008 		goto out;
2009 	}
2010 	pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
2011 	if (ini->smcd_version & SMC_V2) {
2012 		if (!smc_ism_is_v2_capable()) {
2013 			ini->smcd_version &= ~SMC_V2;
2014 			rc = SMC_CLC_DECL_NOISM2SUPP;
2015 		} else if (!pclc_smcd_v2_ext) {
2016 			ini->smcd_version &= ~SMC_V2;
2017 			rc = SMC_CLC_DECL_NOV2DEXT;
2018 		} else if (!pclc_v2_ext->hdr.eid_cnt &&
2019 			   !pclc_v2_ext->hdr.flag.seid) {
2020 			ini->smcd_version &= ~SMC_V2;
2021 			rc = SMC_CLC_DECL_NOUEID;
2022 		}
2023 	}
2024 	if (ini->smcr_version & SMC_V2) {
2025 		if (!pclc_v2_ext->hdr.eid_cnt) {
2026 			ini->smcr_version &= ~SMC_V2;
2027 			rc = SMC_CLC_DECL_NOUEID;
2028 		}
2029 	}
2030 
2031 	ini->release_nr = pclc_v2_ext->hdr.flag.release;
2032 	if (pclc_v2_ext->hdr.flag.release > SMC_RELEASE)
2033 		ini->release_nr = SMC_RELEASE;
2034 
2035 out:
2036 	if (!ini->smcd_version && !ini->smcr_version)
2037 		return rc;
2038 
2039 	return 0;
2040 }
2041 
2042 /* listen worker: check prefixes */
2043 static int smc_listen_prfx_check(struct smc_sock *new_smc,
2044 				 struct smc_clc_msg_proposal *pclc)
2045 {
2046 	struct smc_clc_msg_proposal_prefix *pclc_prfx;
2047 	struct socket *newclcsock = new_smc->clcsock;
2048 
2049 	if (pclc->hdr.typev1 == SMC_TYPE_N)
2050 		return 0;
2051 	pclc_prfx = smc_clc_proposal_get_prefix(pclc);
2052 	if (smc_clc_prfx_match(newclcsock, pclc_prfx))
2053 		return SMC_CLC_DECL_DIFFPREFIX;
2054 
2055 	return 0;
2056 }
2057 
2058 /* listen worker: initialize connection and buffers */
2059 static int smc_listen_rdma_init(struct smc_sock *new_smc,
2060 				struct smc_init_info *ini)
2061 {
2062 	int rc;
2063 
2064 	/* allocate connection / link group */
2065 	rc = smc_conn_create(new_smc, ini);
2066 	if (rc)
2067 		return rc;
2068 
2069 	/* create send buffer and rmb */
2070 	if (smc_buf_create(new_smc, false)) {
2071 		smc_conn_abort(new_smc, ini->first_contact_local);
2072 		return SMC_CLC_DECL_MEM;
2073 	}
2074 
2075 	return 0;
2076 }
2077 
2078 /* listen worker: initialize connection and buffers for SMC-D */
2079 static int smc_listen_ism_init(struct smc_sock *new_smc,
2080 			       struct smc_init_info *ini)
2081 {
2082 	int rc;
2083 
2084 	rc = smc_conn_create(new_smc, ini);
2085 	if (rc)
2086 		return rc;
2087 
2088 	/* Create send and receive buffers */
2089 	rc = smc_buf_create(new_smc, true);
2090 	if (rc) {
2091 		smc_conn_abort(new_smc, ini->first_contact_local);
2092 		return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2093 					 SMC_CLC_DECL_MEM;
2094 	}
2095 
2096 	return 0;
2097 }
2098 
2099 static bool smc_is_already_selected(struct smcd_dev *smcd,
2100 				    struct smc_init_info *ini,
2101 				    int matches)
2102 {
2103 	int i;
2104 
2105 	for (i = 0; i < matches; i++)
2106 		if (smcd == ini->ism_dev[i])
2107 			return true;
2108 
2109 	return false;
2110 }
2111 
2112 /* check for ISM devices matching proposed ISM devices */
2113 static void smc_check_ism_v2_match(struct smc_init_info *ini,
2114 				   u16 proposed_chid,
2115 				   struct smcd_gid *proposed_gid,
2116 				   unsigned int *matches)
2117 {
2118 	struct smcd_dev *smcd;
2119 
2120 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2121 		if (smcd->going_away)
2122 			continue;
2123 		if (smc_is_already_selected(smcd, ini, *matches))
2124 			continue;
2125 		if (smc_ism_get_chid(smcd) == proposed_chid &&
2126 		    !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2127 			ini->ism_peer_gid[*matches].gid = proposed_gid->gid;
2128 			if (__smc_ism_is_emulated(proposed_chid))
2129 				ini->ism_peer_gid[*matches].gid_ext =
2130 							proposed_gid->gid_ext;
2131 				/* non-Emulated-ISM's peer gid_ext remains 0. */
2132 			ini->ism_dev[*matches] = smcd;
2133 			(*matches)++;
2134 			break;
2135 		}
2136 	}
2137 }
2138 
2139 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2140 {
2141 	if (!ini->rc)
2142 		ini->rc = rc;
2143 }
2144 
2145 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2146 					struct smc_clc_msg_proposal *pclc,
2147 					struct smc_init_info *ini)
2148 {
2149 	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2150 	struct smc_clc_v2_extension *smc_v2_ext;
2151 	struct smc_clc_msg_smcd *pclc_smcd;
2152 	unsigned int matches = 0;
2153 	struct smcd_gid smcd_gid;
2154 	u8 smcd_version;
2155 	u8 *eid = NULL;
2156 	int i, rc;
2157 	u16 chid;
2158 
2159 	if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2160 		goto not_found;
2161 
2162 	pclc_smcd = smc_get_clc_msg_smcd(pclc);
2163 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2164 	smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2165 
2166 	mutex_lock(&smcd_dev_list.mutex);
2167 	if (pclc_smcd->ism.chid) {
2168 		/* check for ISM device matching proposed native ISM device */
2169 		smcd_gid.gid = ntohll(pclc_smcd->ism.gid);
2170 		smcd_gid.gid_ext = 0;
2171 		smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2172 				       &smcd_gid, &matches);
2173 	}
2174 	for (i = 0; i < smc_v2_ext->hdr.ism_gid_cnt; i++) {
2175 		/* check for ISM devices matching proposed non-native ISM
2176 		 * devices
2177 		 */
2178 		smcd_gid.gid = ntohll(smcd_v2_ext->gidchid[i].gid);
2179 		smcd_gid.gid_ext = 0;
2180 		chid = ntohs(smcd_v2_ext->gidchid[i].chid);
2181 		if (__smc_ism_is_emulated(chid)) {
2182 			if ((i + 1) == smc_v2_ext->hdr.ism_gid_cnt ||
2183 			    chid != ntohs(smcd_v2_ext->gidchid[i + 1].chid))
2184 				/* each Emulated-ISM device takes two GID-CHID
2185 				 * entries and CHID of the second entry repeats
2186 				 * that of the first entry.
2187 				 *
2188 				 * So check if the next GID-CHID entry exists
2189 				 * and both two entries' CHIDs are the same.
2190 				 */
2191 				continue;
2192 			smcd_gid.gid_ext =
2193 				ntohll(smcd_v2_ext->gidchid[++i].gid);
2194 		}
2195 		smc_check_ism_v2_match(ini, chid, &smcd_gid, &matches);
2196 	}
2197 	mutex_unlock(&smcd_dev_list.mutex);
2198 
2199 	if (!ini->ism_dev[0]) {
2200 		smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2201 		goto not_found;
2202 	}
2203 
2204 	smc_ism_get_system_eid(&eid);
2205 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2206 			       smcd_v2_ext->system_eid, eid))
2207 		goto not_found;
2208 
2209 	/* separate - outside the smcd_dev_list.lock */
2210 	smcd_version = ini->smcd_version;
2211 	for (i = 0; i < matches; i++) {
2212 		ini->smcd_version = SMC_V2;
2213 		ini->is_smcd = true;
2214 		ini->ism_selected = i;
2215 		rc = smc_listen_ism_init(new_smc, ini);
2216 		if (rc) {
2217 			smc_find_ism_store_rc(rc, ini);
2218 			/* try next active ISM device */
2219 			continue;
2220 		}
2221 		return; /* matching and usable V2 ISM device found */
2222 	}
2223 	/* no V2 ISM device could be initialized */
2224 	ini->smcd_version = smcd_version;	/* restore original value */
2225 	ini->negotiated_eid[0] = 0;
2226 
2227 not_found:
2228 	ini->smcd_version &= ~SMC_V2;
2229 	ini->ism_dev[0] = NULL;
2230 	ini->is_smcd = false;
2231 }
2232 
2233 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2234 					struct smc_clc_msg_proposal *pclc,
2235 					struct smc_init_info *ini)
2236 {
2237 	struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2238 	int rc = 0;
2239 
2240 	/* check if ISM V1 is available */
2241 	if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2242 		goto not_found;
2243 	ini->is_smcd = true; /* prepare ISM check */
2244 	ini->ism_peer_gid[0].gid = ntohll(pclc_smcd->ism.gid);
2245 	ini->ism_peer_gid[0].gid_ext = 0;
2246 	rc = smc_find_ism_device(new_smc, ini);
2247 	if (rc)
2248 		goto not_found;
2249 	ini->ism_selected = 0;
2250 	rc = smc_listen_ism_init(new_smc, ini);
2251 	if (!rc)
2252 		return;		/* V1 ISM device found */
2253 
2254 not_found:
2255 	smc_find_ism_store_rc(rc, ini);
2256 	ini->smcd_version &= ~SMC_V1;
2257 	ini->ism_dev[0] = NULL;
2258 	ini->is_smcd = false;
2259 }
2260 
2261 /* listen worker: register buffers */
2262 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2263 {
2264 	struct smc_connection *conn = &new_smc->conn;
2265 
2266 	if (!local_first) {
2267 		/* reg sendbufs if they were vzalloced */
2268 		if (conn->sndbuf_desc->is_vm) {
2269 			if (smcr_lgr_reg_sndbufs(conn->lnk,
2270 						 conn->sndbuf_desc))
2271 				return SMC_CLC_DECL_ERR_REGBUF;
2272 		}
2273 		if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2274 			return SMC_CLC_DECL_ERR_REGBUF;
2275 	}
2276 
2277 	return 0;
2278 }
2279 
2280 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2281 					 struct smc_clc_msg_proposal *pclc,
2282 					 struct smc_init_info *ini)
2283 {
2284 	struct smc_clc_v2_extension *smc_v2_ext;
2285 	u8 smcr_version;
2286 	int rc;
2287 
2288 	if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2289 		goto not_found;
2290 
2291 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2292 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2293 		goto not_found;
2294 
2295 	/* prepare RDMA check */
2296 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2297 	memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2298 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2299 	ini->check_smcrv2 = true;
2300 	ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2301 	ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2302 	ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2303 	rc = smc_find_rdma_device(new_smc, ini);
2304 	if (rc) {
2305 		smc_find_ism_store_rc(rc, ini);
2306 		goto not_found;
2307 	}
2308 	if (!ini->smcrv2.uses_gateway)
2309 		memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2310 
2311 	smcr_version = ini->smcr_version;
2312 	ini->smcr_version = SMC_V2;
2313 	rc = smc_listen_rdma_init(new_smc, ini);
2314 	if (!rc) {
2315 		rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2316 		if (rc)
2317 			smc_conn_abort(new_smc, ini->first_contact_local);
2318 	}
2319 	if (!rc)
2320 		return;
2321 	ini->smcr_version = smcr_version;
2322 	smc_find_ism_store_rc(rc, ini);
2323 
2324 not_found:
2325 	ini->smcr_version &= ~SMC_V2;
2326 	ini->smcrv2.ib_dev_v2 = NULL;
2327 	ini->check_smcrv2 = false;
2328 }
2329 
2330 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2331 					struct smc_clc_msg_proposal *pclc,
2332 					struct smc_init_info *ini)
2333 {
2334 	int rc;
2335 
2336 	if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2337 		return SMC_CLC_DECL_NOSMCDEV;
2338 
2339 	/* prepare RDMA check */
2340 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2341 	memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2342 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2343 	rc = smc_find_rdma_device(new_smc, ini);
2344 	if (rc) {
2345 		/* no RDMA device found */
2346 		return SMC_CLC_DECL_NOSMCDEV;
2347 	}
2348 	rc = smc_listen_rdma_init(new_smc, ini);
2349 	if (rc)
2350 		return rc;
2351 	return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2352 }
2353 
2354 /* determine the local device matching to proposal */
2355 static int smc_listen_find_device(struct smc_sock *new_smc,
2356 				  struct smc_clc_msg_proposal *pclc,
2357 				  struct smc_init_info *ini)
2358 {
2359 	int prfx_rc;
2360 
2361 	/* check for ISM device matching V2 proposed device */
2362 	smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2363 	if (ini->ism_dev[0])
2364 		return 0;
2365 
2366 	/* check for matching IP prefix and subnet length (V1) */
2367 	prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2368 	if (prfx_rc)
2369 		smc_find_ism_store_rc(prfx_rc, ini);
2370 
2371 	/* get vlan id from IP device */
2372 	if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2373 		return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2374 
2375 	/* check for ISM device matching V1 proposed device */
2376 	if (!prfx_rc)
2377 		smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2378 	if (ini->ism_dev[0])
2379 		return 0;
2380 
2381 	if (!smcr_indicated(pclc->hdr.typev1) &&
2382 	    !smcr_indicated(pclc->hdr.typev2))
2383 		/* skip RDMA and decline */
2384 		return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2385 
2386 	/* check if RDMA V2 is available */
2387 	smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2388 	if (ini->smcrv2.ib_dev_v2)
2389 		return 0;
2390 
2391 	/* check if RDMA V1 is available */
2392 	if (!prfx_rc) {
2393 		int rc;
2394 
2395 		rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2396 		smc_find_ism_store_rc(rc, ini);
2397 		return (!rc) ? 0 : ini->rc;
2398 	}
2399 	return prfx_rc;
2400 }
2401 
2402 /* listen worker: finish RDMA setup */
2403 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2404 				  struct smc_clc_msg_accept_confirm *cclc,
2405 				  bool local_first,
2406 				  struct smc_init_info *ini)
2407 {
2408 	struct smc_link *link = new_smc->conn.lnk;
2409 	int reason_code = 0;
2410 
2411 	if (local_first)
2412 		smc_link_save_peer_info(link, cclc, ini);
2413 
2414 	if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2415 		return SMC_CLC_DECL_ERR_RTOK;
2416 
2417 	if (local_first) {
2418 		if (smc_ib_ready_link(link))
2419 			return SMC_CLC_DECL_ERR_RDYLNK;
2420 		/* QP confirmation over RoCE fabric */
2421 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2422 		reason_code = smcr_serv_conf_first_link(new_smc);
2423 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2424 	}
2425 	return reason_code;
2426 }
2427 
2428 /* setup for connection of server */
2429 static void smc_listen_work(struct work_struct *work)
2430 {
2431 	struct smc_sock *new_smc = container_of(work, struct smc_sock,
2432 						smc_listen_work);
2433 	struct socket *newclcsock = new_smc->clcsock;
2434 	struct smc_clc_msg_accept_confirm *cclc;
2435 	struct smc_clc_msg_proposal_area *buf;
2436 	struct smc_clc_msg_proposal *pclc;
2437 	struct smc_init_info *ini = NULL;
2438 	u8 proposal_version = SMC_V1;
2439 	u8 accept_version;
2440 	int rc = 0;
2441 
2442 	if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2443 		return smc_listen_out_err(new_smc);
2444 
2445 	if (new_smc->use_fallback) {
2446 		smc_listen_out_connected(new_smc);
2447 		return;
2448 	}
2449 
2450 	/* check if peer is smc capable */
2451 	if (!tcp_sk(newclcsock->sk)->syn_smc) {
2452 		rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2453 		if (rc)
2454 			smc_listen_out_err(new_smc);
2455 		else
2456 			smc_listen_out_connected(new_smc);
2457 		return;
2458 	}
2459 
2460 	/* do inband token exchange -
2461 	 * wait for and receive SMC Proposal CLC message
2462 	 */
2463 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2464 	if (!buf) {
2465 		rc = SMC_CLC_DECL_MEM;
2466 		goto out_decl;
2467 	}
2468 	pclc = (struct smc_clc_msg_proposal *)buf;
2469 	rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2470 			      SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2471 	if (rc)
2472 		goto out_decl;
2473 
2474 	if (pclc->hdr.version > SMC_V1)
2475 		proposal_version = SMC_V2;
2476 
2477 	/* IPSec connections opt out of SMC optimizations */
2478 	if (using_ipsec(new_smc)) {
2479 		rc = SMC_CLC_DECL_IPSEC;
2480 		goto out_decl;
2481 	}
2482 
2483 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2484 	if (!ini) {
2485 		rc = SMC_CLC_DECL_MEM;
2486 		goto out_decl;
2487 	}
2488 
2489 	/* initial version checking */
2490 	rc = smc_listen_v2_check(new_smc, pclc, ini);
2491 	if (rc)
2492 		goto out_decl;
2493 
2494 	rc = smc_clc_srv_v2x_features_validate(new_smc, pclc, ini);
2495 	if (rc)
2496 		goto out_decl;
2497 
2498 	mutex_lock(&smc_server_lgr_pending);
2499 	smc_close_init(new_smc);
2500 	smc_rx_init(new_smc);
2501 	smc_tx_init(new_smc);
2502 
2503 	/* determine ISM or RoCE device used for connection */
2504 	rc = smc_listen_find_device(new_smc, pclc, ini);
2505 	if (rc)
2506 		goto out_unlock;
2507 
2508 	/* send SMC Accept CLC message */
2509 	accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2510 	rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2511 				 accept_version, ini->negotiated_eid, ini);
2512 	if (rc)
2513 		goto out_unlock;
2514 
2515 	/* SMC-D does not need this lock any more */
2516 	if (ini->is_smcd)
2517 		mutex_unlock(&smc_server_lgr_pending);
2518 
2519 	/* receive SMC Confirm CLC message */
2520 	memset(buf, 0, sizeof(*buf));
2521 	cclc = (struct smc_clc_msg_accept_confirm *)buf;
2522 	rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2523 			      SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2524 	if (rc) {
2525 		if (!ini->is_smcd)
2526 			goto out_unlock;
2527 		goto out_decl;
2528 	}
2529 
2530 	rc = smc_clc_v2x_features_confirm_check(cclc, ini);
2531 	if (rc) {
2532 		if (!ini->is_smcd)
2533 			goto out_unlock;
2534 		goto out_decl;
2535 	}
2536 
2537 	/* fce smc release version is needed in smc_listen_rdma_finish,
2538 	 * so save fce info here.
2539 	 */
2540 	smc_conn_save_peer_info_fce(new_smc, cclc);
2541 
2542 	/* finish worker */
2543 	if (!ini->is_smcd) {
2544 		rc = smc_listen_rdma_finish(new_smc, cclc,
2545 					    ini->first_contact_local, ini);
2546 		if (rc)
2547 			goto out_unlock;
2548 		mutex_unlock(&smc_server_lgr_pending);
2549 	}
2550 	smc_conn_save_peer_info(new_smc, cclc);
2551 
2552 	if (ini->is_smcd &&
2553 	    smc_ism_support_dmb_nocopy(new_smc->conn.lgr->smcd)) {
2554 		rc = smcd_buf_attach(new_smc);
2555 		if (rc)
2556 			goto out_decl;
2557 	}
2558 
2559 	smc_listen_out_connected(new_smc);
2560 	SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2561 	goto out_free;
2562 
2563 out_unlock:
2564 	mutex_unlock(&smc_server_lgr_pending);
2565 out_decl:
2566 	smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2567 			   proposal_version);
2568 out_free:
2569 	kfree(ini);
2570 	kfree(buf);
2571 }
2572 
2573 static void smc_tcp_listen_work(struct work_struct *work)
2574 {
2575 	struct smc_sock *lsmc = container_of(work, struct smc_sock,
2576 					     tcp_listen_work);
2577 	struct sock *lsk = &lsmc->sk;
2578 	struct smc_sock *new_smc;
2579 	int rc = 0;
2580 
2581 	lock_sock(lsk);
2582 	while (lsk->sk_state == SMC_LISTEN) {
2583 		rc = smc_clcsock_accept(lsmc, &new_smc);
2584 		if (rc) /* clcsock accept queue empty or error */
2585 			goto out;
2586 		if (!new_smc)
2587 			continue;
2588 
2589 		if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2590 			atomic_inc(&lsmc->queued_smc_hs);
2591 
2592 		new_smc->listen_smc = lsmc;
2593 		new_smc->use_fallback = lsmc->use_fallback;
2594 		new_smc->fallback_rsn = lsmc->fallback_rsn;
2595 		sock_hold(lsk); /* sock_put in smc_listen_work */
2596 		INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2597 		smc_copy_sock_settings_to_smc(new_smc);
2598 		sock_hold(&new_smc->sk); /* sock_put in passive closing */
2599 		if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2600 			sock_put(&new_smc->sk);
2601 	}
2602 
2603 out:
2604 	release_sock(lsk);
2605 	sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2606 }
2607 
2608 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2609 {
2610 	struct smc_sock *lsmc;
2611 
2612 	read_lock_bh(&listen_clcsock->sk_callback_lock);
2613 	lsmc = smc_clcsock_user_data(listen_clcsock);
2614 	if (!lsmc)
2615 		goto out;
2616 	lsmc->clcsk_data_ready(listen_clcsock);
2617 	if (lsmc->sk.sk_state == SMC_LISTEN) {
2618 		sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2619 		if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2620 			sock_put(&lsmc->sk);
2621 	}
2622 out:
2623 	read_unlock_bh(&listen_clcsock->sk_callback_lock);
2624 }
2625 
2626 static int smc_listen(struct socket *sock, int backlog)
2627 {
2628 	struct sock *sk = sock->sk;
2629 	struct smc_sock *smc;
2630 	int rc;
2631 
2632 	smc = smc_sk(sk);
2633 	lock_sock(sk);
2634 
2635 	rc = -EINVAL;
2636 	if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2637 	    smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2638 		goto out;
2639 
2640 	rc = 0;
2641 	if (sk->sk_state == SMC_LISTEN) {
2642 		sk->sk_max_ack_backlog = backlog;
2643 		goto out;
2644 	}
2645 	/* some socket options are handled in core, so we could not apply
2646 	 * them to the clc socket -- copy smc socket options to clc socket
2647 	 */
2648 	smc_copy_sock_settings_to_clc(smc);
2649 	if (!smc->use_fallback)
2650 		tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2651 
2652 	/* save original sk_data_ready function and establish
2653 	 * smc-specific sk_data_ready function
2654 	 */
2655 	write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2656 	smc->clcsock->sk->sk_user_data =
2657 		(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2658 	smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2659 			       smc_clcsock_data_ready, &smc->clcsk_data_ready);
2660 	write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2661 
2662 	/* save original ops */
2663 	smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2664 
2665 	smc->af_ops = *smc->ori_af_ops;
2666 	smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2667 
2668 	inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2669 
2670 	if (smc->limit_smc_hs)
2671 		tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2672 
2673 	rc = kernel_listen(smc->clcsock, backlog);
2674 	if (rc) {
2675 		write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2676 		smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2677 				       &smc->clcsk_data_ready);
2678 		smc->clcsock->sk->sk_user_data = NULL;
2679 		write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2680 		goto out;
2681 	}
2682 	sk->sk_max_ack_backlog = backlog;
2683 	sk->sk_ack_backlog = 0;
2684 	sk->sk_state = SMC_LISTEN;
2685 
2686 out:
2687 	release_sock(sk);
2688 	return rc;
2689 }
2690 
2691 static int smc_accept(struct socket *sock, struct socket *new_sock,
2692 		      struct proto_accept_arg *arg)
2693 {
2694 	struct sock *sk = sock->sk, *nsk;
2695 	DECLARE_WAITQUEUE(wait, current);
2696 	struct smc_sock *lsmc;
2697 	long timeo;
2698 	int rc = 0;
2699 
2700 	lsmc = smc_sk(sk);
2701 	sock_hold(sk); /* sock_put below */
2702 	lock_sock(sk);
2703 
2704 	if (lsmc->sk.sk_state != SMC_LISTEN) {
2705 		rc = -EINVAL;
2706 		release_sock(sk);
2707 		goto out;
2708 	}
2709 
2710 	/* Wait for an incoming connection */
2711 	timeo = sock_rcvtimeo(sk, arg->flags & O_NONBLOCK);
2712 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
2713 	while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2714 		set_current_state(TASK_INTERRUPTIBLE);
2715 		if (!timeo) {
2716 			rc = -EAGAIN;
2717 			break;
2718 		}
2719 		release_sock(sk);
2720 		timeo = schedule_timeout(timeo);
2721 		/* wakeup by sk_data_ready in smc_listen_work() */
2722 		sched_annotate_sleep();
2723 		lock_sock(sk);
2724 		if (signal_pending(current)) {
2725 			rc = sock_intr_errno(timeo);
2726 			break;
2727 		}
2728 	}
2729 	set_current_state(TASK_RUNNING);
2730 	remove_wait_queue(sk_sleep(sk), &wait);
2731 
2732 	if (!rc)
2733 		rc = sock_error(nsk);
2734 	release_sock(sk);
2735 	if (rc)
2736 		goto out;
2737 
2738 	if (lsmc->sockopt_defer_accept && !(arg->flags & O_NONBLOCK)) {
2739 		/* wait till data arrives on the socket */
2740 		timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2741 								MSEC_PER_SEC);
2742 		if (smc_sk(nsk)->use_fallback) {
2743 			struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2744 
2745 			lock_sock(clcsk);
2746 			if (skb_queue_empty(&clcsk->sk_receive_queue))
2747 				sk_wait_data(clcsk, &timeo, NULL);
2748 			release_sock(clcsk);
2749 		} else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2750 			lock_sock(nsk);
2751 			smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2752 			release_sock(nsk);
2753 		}
2754 	}
2755 
2756 out:
2757 	sock_put(sk); /* sock_hold above */
2758 	return rc;
2759 }
2760 
2761 static int smc_getname(struct socket *sock, struct sockaddr *addr,
2762 		       int peer)
2763 {
2764 	struct smc_sock *smc;
2765 
2766 	if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2767 	    (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2768 		return -ENOTCONN;
2769 
2770 	smc = smc_sk(sock->sk);
2771 
2772 	return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2773 }
2774 
2775 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2776 {
2777 	struct sock *sk = sock->sk;
2778 	struct smc_sock *smc;
2779 	int rc;
2780 
2781 	smc = smc_sk(sk);
2782 	lock_sock(sk);
2783 
2784 	/* SMC does not support connect with fastopen */
2785 	if (msg->msg_flags & MSG_FASTOPEN) {
2786 		/* not connected yet, fallback */
2787 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2788 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2789 			if (rc)
2790 				goto out;
2791 		} else {
2792 			rc = -EINVAL;
2793 			goto out;
2794 		}
2795 	} else if ((sk->sk_state != SMC_ACTIVE) &&
2796 		   (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2797 		   (sk->sk_state != SMC_INIT)) {
2798 		rc = -EPIPE;
2799 		goto out;
2800 	}
2801 
2802 	if (smc->use_fallback) {
2803 		rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2804 	} else {
2805 		rc = smc_tx_sendmsg(smc, msg, len);
2806 		SMC_STAT_TX_PAYLOAD(smc, len, rc);
2807 	}
2808 out:
2809 	release_sock(sk);
2810 	return rc;
2811 }
2812 
2813 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2814 		       int flags)
2815 {
2816 	struct sock *sk = sock->sk;
2817 	struct smc_sock *smc;
2818 	int rc = -ENOTCONN;
2819 
2820 	smc = smc_sk(sk);
2821 	lock_sock(sk);
2822 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2823 		/* socket was connected before, no more data to read */
2824 		rc = 0;
2825 		goto out;
2826 	}
2827 	if ((sk->sk_state == SMC_INIT) ||
2828 	    (sk->sk_state == SMC_LISTEN) ||
2829 	    (sk->sk_state == SMC_CLOSED))
2830 		goto out;
2831 
2832 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2833 		rc = 0;
2834 		goto out;
2835 	}
2836 
2837 	if (smc->use_fallback) {
2838 		rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2839 	} else {
2840 		msg->msg_namelen = 0;
2841 		rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2842 		SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2843 	}
2844 
2845 out:
2846 	release_sock(sk);
2847 	return rc;
2848 }
2849 
2850 static __poll_t smc_accept_poll(struct sock *parent)
2851 {
2852 	struct smc_sock *isk = smc_sk(parent);
2853 	__poll_t mask = 0;
2854 
2855 	spin_lock(&isk->accept_q_lock);
2856 	if (!list_empty(&isk->accept_q))
2857 		mask = EPOLLIN | EPOLLRDNORM;
2858 	spin_unlock(&isk->accept_q_lock);
2859 
2860 	return mask;
2861 }
2862 
2863 static __poll_t smc_poll(struct file *file, struct socket *sock,
2864 			     poll_table *wait)
2865 {
2866 	struct sock *sk = sock->sk;
2867 	struct smc_sock *smc;
2868 	__poll_t mask = 0;
2869 
2870 	if (!sk)
2871 		return EPOLLNVAL;
2872 
2873 	smc = smc_sk(sock->sk);
2874 	if (smc->use_fallback) {
2875 		/* delegate to CLC child sock */
2876 		mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2877 		sk->sk_err = smc->clcsock->sk->sk_err;
2878 	} else {
2879 		if (sk->sk_state != SMC_CLOSED)
2880 			sock_poll_wait(file, sock, wait);
2881 		if (sk->sk_err)
2882 			mask |= EPOLLERR;
2883 		if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2884 		    (sk->sk_state == SMC_CLOSED))
2885 			mask |= EPOLLHUP;
2886 		if (sk->sk_state == SMC_LISTEN) {
2887 			/* woken up by sk_data_ready in smc_listen_work() */
2888 			mask |= smc_accept_poll(sk);
2889 		} else if (smc->use_fallback) { /* as result of connect_work()*/
2890 			mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2891 							   wait);
2892 			sk->sk_err = smc->clcsock->sk->sk_err;
2893 		} else {
2894 			if ((sk->sk_state != SMC_INIT &&
2895 			     atomic_read(&smc->conn.sndbuf_space)) ||
2896 			    sk->sk_shutdown & SEND_SHUTDOWN) {
2897 				mask |= EPOLLOUT | EPOLLWRNORM;
2898 			} else {
2899 				sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2900 				set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2901 			}
2902 			if (atomic_read(&smc->conn.bytes_to_rcv))
2903 				mask |= EPOLLIN | EPOLLRDNORM;
2904 			if (sk->sk_shutdown & RCV_SHUTDOWN)
2905 				mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2906 			if (sk->sk_state == SMC_APPCLOSEWAIT1)
2907 				mask |= EPOLLIN;
2908 			if (smc->conn.urg_state == SMC_URG_VALID)
2909 				mask |= EPOLLPRI;
2910 		}
2911 	}
2912 
2913 	return mask;
2914 }
2915 
2916 static int smc_shutdown(struct socket *sock, int how)
2917 {
2918 	struct sock *sk = sock->sk;
2919 	bool do_shutdown = true;
2920 	struct smc_sock *smc;
2921 	int rc = -EINVAL;
2922 	int old_state;
2923 	int rc1 = 0;
2924 
2925 	smc = smc_sk(sk);
2926 
2927 	if ((how < SHUT_RD) || (how > SHUT_RDWR))
2928 		return rc;
2929 
2930 	lock_sock(sk);
2931 
2932 	if (sock->state == SS_CONNECTING) {
2933 		if (sk->sk_state == SMC_ACTIVE)
2934 			sock->state = SS_CONNECTED;
2935 		else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2936 			 sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2937 			 sk->sk_state == SMC_APPCLOSEWAIT1 ||
2938 			 sk->sk_state == SMC_APPCLOSEWAIT2 ||
2939 			 sk->sk_state == SMC_APPFINCLOSEWAIT)
2940 			sock->state = SS_DISCONNECTING;
2941 	}
2942 
2943 	rc = -ENOTCONN;
2944 	if ((sk->sk_state != SMC_ACTIVE) &&
2945 	    (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2946 	    (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2947 	    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2948 	    (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2949 	    (sk->sk_state != SMC_APPFINCLOSEWAIT))
2950 		goto out;
2951 	if (smc->use_fallback) {
2952 		rc = kernel_sock_shutdown(smc->clcsock, how);
2953 		sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2954 		if (sk->sk_shutdown == SHUTDOWN_MASK) {
2955 			sk->sk_state = SMC_CLOSED;
2956 			sk->sk_socket->state = SS_UNCONNECTED;
2957 			sock_put(sk);
2958 		}
2959 		goto out;
2960 	}
2961 	switch (how) {
2962 	case SHUT_RDWR:		/* shutdown in both directions */
2963 		old_state = sk->sk_state;
2964 		rc = smc_close_active(smc);
2965 		if (old_state == SMC_ACTIVE &&
2966 		    sk->sk_state == SMC_PEERCLOSEWAIT1)
2967 			do_shutdown = false;
2968 		break;
2969 	case SHUT_WR:
2970 		rc = smc_close_shutdown_write(smc);
2971 		break;
2972 	case SHUT_RD:
2973 		rc = 0;
2974 		/* nothing more to do because peer is not involved */
2975 		break;
2976 	}
2977 	if (do_shutdown && smc->clcsock)
2978 		rc1 = kernel_sock_shutdown(smc->clcsock, how);
2979 	/* map sock_shutdown_cmd constants to sk_shutdown value range */
2980 	sk->sk_shutdown |= how + 1;
2981 
2982 	if (sk->sk_state == SMC_CLOSED)
2983 		sock->state = SS_UNCONNECTED;
2984 	else
2985 		sock->state = SS_DISCONNECTING;
2986 out:
2987 	release_sock(sk);
2988 	return rc ? rc : rc1;
2989 }
2990 
2991 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2992 			    char __user *optval, int __user *optlen)
2993 {
2994 	struct smc_sock *smc;
2995 	int val, len;
2996 
2997 	smc = smc_sk(sock->sk);
2998 
2999 	if (get_user(len, optlen))
3000 		return -EFAULT;
3001 
3002 	len = min_t(int, len, sizeof(int));
3003 
3004 	if (len < 0)
3005 		return -EINVAL;
3006 
3007 	switch (optname) {
3008 	case SMC_LIMIT_HS:
3009 		val = smc->limit_smc_hs;
3010 		break;
3011 	default:
3012 		return -EOPNOTSUPP;
3013 	}
3014 
3015 	if (put_user(len, optlen))
3016 		return -EFAULT;
3017 	if (copy_to_user(optval, &val, len))
3018 		return -EFAULT;
3019 
3020 	return 0;
3021 }
3022 
3023 static int __smc_setsockopt(struct socket *sock, int level, int optname,
3024 			    sockptr_t optval, unsigned int optlen)
3025 {
3026 	struct sock *sk = sock->sk;
3027 	struct smc_sock *smc;
3028 	int val, rc;
3029 
3030 	smc = smc_sk(sk);
3031 
3032 	lock_sock(sk);
3033 	switch (optname) {
3034 	case SMC_LIMIT_HS:
3035 		if (optlen < sizeof(int)) {
3036 			rc = -EINVAL;
3037 			break;
3038 		}
3039 		if (copy_from_sockptr(&val, optval, sizeof(int))) {
3040 			rc = -EFAULT;
3041 			break;
3042 		}
3043 
3044 		smc->limit_smc_hs = !!val;
3045 		rc = 0;
3046 		break;
3047 	default:
3048 		rc = -EOPNOTSUPP;
3049 		break;
3050 	}
3051 	release_sock(sk);
3052 
3053 	return rc;
3054 }
3055 
3056 static int smc_setsockopt(struct socket *sock, int level, int optname,
3057 			  sockptr_t optval, unsigned int optlen)
3058 {
3059 	struct sock *sk = sock->sk;
3060 	struct smc_sock *smc;
3061 	int val, rc;
3062 
3063 	if (level == SOL_TCP && optname == TCP_ULP)
3064 		return -EOPNOTSUPP;
3065 	else if (level == SOL_SMC)
3066 		return __smc_setsockopt(sock, level, optname, optval, optlen);
3067 
3068 	smc = smc_sk(sk);
3069 
3070 	/* generic setsockopts reaching us here always apply to the
3071 	 * CLC socket
3072 	 */
3073 	mutex_lock(&smc->clcsock_release_lock);
3074 	if (!smc->clcsock) {
3075 		mutex_unlock(&smc->clcsock_release_lock);
3076 		return -EBADF;
3077 	}
3078 	if (unlikely(!smc->clcsock->ops->setsockopt))
3079 		rc = -EOPNOTSUPP;
3080 	else
3081 		rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
3082 						   optval, optlen);
3083 	if (smc->clcsock->sk->sk_err) {
3084 		sk->sk_err = smc->clcsock->sk->sk_err;
3085 		sk_error_report(sk);
3086 	}
3087 	mutex_unlock(&smc->clcsock_release_lock);
3088 
3089 	if (optlen < sizeof(int))
3090 		return -EINVAL;
3091 	if (copy_from_sockptr(&val, optval, sizeof(int)))
3092 		return -EFAULT;
3093 
3094 	lock_sock(sk);
3095 	if (rc || smc->use_fallback)
3096 		goto out;
3097 	switch (optname) {
3098 	case TCP_FASTOPEN:
3099 	case TCP_FASTOPEN_CONNECT:
3100 	case TCP_FASTOPEN_KEY:
3101 	case TCP_FASTOPEN_NO_COOKIE:
3102 		/* option not supported by SMC */
3103 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
3104 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
3105 		} else {
3106 			rc = -EINVAL;
3107 		}
3108 		break;
3109 	case TCP_NODELAY:
3110 		if (sk->sk_state != SMC_INIT &&
3111 		    sk->sk_state != SMC_LISTEN &&
3112 		    sk->sk_state != SMC_CLOSED) {
3113 			if (val) {
3114 				SMC_STAT_INC(smc, ndly_cnt);
3115 				smc_tx_pending(&smc->conn);
3116 				cancel_delayed_work(&smc->conn.tx_work);
3117 			}
3118 		}
3119 		break;
3120 	case TCP_CORK:
3121 		if (sk->sk_state != SMC_INIT &&
3122 		    sk->sk_state != SMC_LISTEN &&
3123 		    sk->sk_state != SMC_CLOSED) {
3124 			if (!val) {
3125 				SMC_STAT_INC(smc, cork_cnt);
3126 				smc_tx_pending(&smc->conn);
3127 				cancel_delayed_work(&smc->conn.tx_work);
3128 			}
3129 		}
3130 		break;
3131 	case TCP_DEFER_ACCEPT:
3132 		smc->sockopt_defer_accept = val;
3133 		break;
3134 	default:
3135 		break;
3136 	}
3137 out:
3138 	release_sock(sk);
3139 
3140 	return rc;
3141 }
3142 
3143 static int smc_getsockopt(struct socket *sock, int level, int optname,
3144 			  char __user *optval, int __user *optlen)
3145 {
3146 	struct smc_sock *smc;
3147 	int rc;
3148 
3149 	if (level == SOL_SMC)
3150 		return __smc_getsockopt(sock, level, optname, optval, optlen);
3151 
3152 	smc = smc_sk(sock->sk);
3153 	mutex_lock(&smc->clcsock_release_lock);
3154 	if (!smc->clcsock) {
3155 		mutex_unlock(&smc->clcsock_release_lock);
3156 		return -EBADF;
3157 	}
3158 	/* socket options apply to the CLC socket */
3159 	if (unlikely(!smc->clcsock->ops->getsockopt)) {
3160 		mutex_unlock(&smc->clcsock_release_lock);
3161 		return -EOPNOTSUPP;
3162 	}
3163 	rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3164 					   optval, optlen);
3165 	mutex_unlock(&smc->clcsock_release_lock);
3166 	return rc;
3167 }
3168 
3169 static int smc_ioctl(struct socket *sock, unsigned int cmd,
3170 		     unsigned long arg)
3171 {
3172 	union smc_host_cursor cons, urg;
3173 	struct smc_connection *conn;
3174 	struct smc_sock *smc;
3175 	int answ;
3176 
3177 	smc = smc_sk(sock->sk);
3178 	conn = &smc->conn;
3179 	lock_sock(&smc->sk);
3180 	if (smc->use_fallback) {
3181 		if (!smc->clcsock) {
3182 			release_sock(&smc->sk);
3183 			return -EBADF;
3184 		}
3185 		answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3186 		release_sock(&smc->sk);
3187 		return answ;
3188 	}
3189 	switch (cmd) {
3190 	case SIOCINQ: /* same as FIONREAD */
3191 		if (smc->sk.sk_state == SMC_LISTEN) {
3192 			release_sock(&smc->sk);
3193 			return -EINVAL;
3194 		}
3195 		if (smc->sk.sk_state == SMC_INIT ||
3196 		    smc->sk.sk_state == SMC_CLOSED)
3197 			answ = 0;
3198 		else
3199 			answ = atomic_read(&smc->conn.bytes_to_rcv);
3200 		break;
3201 	case SIOCOUTQ:
3202 		/* output queue size (not send + not acked) */
3203 		if (smc->sk.sk_state == SMC_LISTEN) {
3204 			release_sock(&smc->sk);
3205 			return -EINVAL;
3206 		}
3207 		if (smc->sk.sk_state == SMC_INIT ||
3208 		    smc->sk.sk_state == SMC_CLOSED)
3209 			answ = 0;
3210 		else
3211 			answ = smc->conn.sndbuf_desc->len -
3212 					atomic_read(&smc->conn.sndbuf_space);
3213 		break;
3214 	case SIOCOUTQNSD:
3215 		/* output queue size (not send only) */
3216 		if (smc->sk.sk_state == SMC_LISTEN) {
3217 			release_sock(&smc->sk);
3218 			return -EINVAL;
3219 		}
3220 		if (smc->sk.sk_state == SMC_INIT ||
3221 		    smc->sk.sk_state == SMC_CLOSED)
3222 			answ = 0;
3223 		else
3224 			answ = smc_tx_prepared_sends(&smc->conn);
3225 		break;
3226 	case SIOCATMARK:
3227 		if (smc->sk.sk_state == SMC_LISTEN) {
3228 			release_sock(&smc->sk);
3229 			return -EINVAL;
3230 		}
3231 		if (smc->sk.sk_state == SMC_INIT ||
3232 		    smc->sk.sk_state == SMC_CLOSED) {
3233 			answ = 0;
3234 		} else {
3235 			smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3236 			smc_curs_copy(&urg, &conn->urg_curs, conn);
3237 			answ = smc_curs_diff(conn->rmb_desc->len,
3238 					     &cons, &urg) == 1;
3239 		}
3240 		break;
3241 	default:
3242 		release_sock(&smc->sk);
3243 		return -ENOIOCTLCMD;
3244 	}
3245 	release_sock(&smc->sk);
3246 
3247 	return put_user(answ, (int __user *)arg);
3248 }
3249 
3250 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3251  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3252  * updates till whenever a respective page has been fully processed.
3253  * Note that subsequent recv() calls have to wait till all splice() processing
3254  * completed.
3255  */
3256 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3257 			       struct pipe_inode_info *pipe, size_t len,
3258 			       unsigned int flags)
3259 {
3260 	struct sock *sk = sock->sk;
3261 	struct smc_sock *smc;
3262 	int rc = -ENOTCONN;
3263 
3264 	smc = smc_sk(sk);
3265 	lock_sock(sk);
3266 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3267 		/* socket was connected before, no more data to read */
3268 		rc = 0;
3269 		goto out;
3270 	}
3271 	if (sk->sk_state == SMC_INIT ||
3272 	    sk->sk_state == SMC_LISTEN ||
3273 	    sk->sk_state == SMC_CLOSED)
3274 		goto out;
3275 
3276 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3277 		rc = 0;
3278 		goto out;
3279 	}
3280 
3281 	if (smc->use_fallback) {
3282 		rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3283 						    pipe, len, flags);
3284 	} else {
3285 		if (*ppos) {
3286 			rc = -ESPIPE;
3287 			goto out;
3288 		}
3289 		if (flags & SPLICE_F_NONBLOCK)
3290 			flags = MSG_DONTWAIT;
3291 		else
3292 			flags = 0;
3293 		SMC_STAT_INC(smc, splice_cnt);
3294 		rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3295 	}
3296 out:
3297 	release_sock(sk);
3298 
3299 	return rc;
3300 }
3301 
3302 /* must look like tcp */
3303 static const struct proto_ops smc_sock_ops = {
3304 	.family		= PF_SMC,
3305 	.owner		= THIS_MODULE,
3306 	.release	= smc_release,
3307 	.bind		= smc_bind,
3308 	.connect	= smc_connect,
3309 	.socketpair	= sock_no_socketpair,
3310 	.accept		= smc_accept,
3311 	.getname	= smc_getname,
3312 	.poll		= smc_poll,
3313 	.ioctl		= smc_ioctl,
3314 	.listen		= smc_listen,
3315 	.shutdown	= smc_shutdown,
3316 	.setsockopt	= smc_setsockopt,
3317 	.getsockopt	= smc_getsockopt,
3318 	.sendmsg	= smc_sendmsg,
3319 	.recvmsg	= smc_recvmsg,
3320 	.mmap		= sock_no_mmap,
3321 	.splice_read	= smc_splice_read,
3322 };
3323 
3324 static int __smc_create(struct net *net, struct socket *sock, int protocol,
3325 			int kern, struct socket *clcsock)
3326 {
3327 	int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3328 	struct smc_sock *smc;
3329 	struct sock *sk;
3330 	int rc;
3331 
3332 	rc = -ESOCKTNOSUPPORT;
3333 	if (sock->type != SOCK_STREAM)
3334 		goto out;
3335 
3336 	rc = -EPROTONOSUPPORT;
3337 	if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3338 		goto out;
3339 
3340 	rc = -ENOBUFS;
3341 	sock->ops = &smc_sock_ops;
3342 	sock->state = SS_UNCONNECTED;
3343 	sk = smc_sock_alloc(net, sock, protocol);
3344 	if (!sk)
3345 		goto out;
3346 
3347 	/* create internal TCP socket for CLC handshake and fallback */
3348 	smc = smc_sk(sk);
3349 	smc->use_fallback = false; /* assume rdma capability first */
3350 	smc->fallback_rsn = 0;
3351 
3352 	/* default behavior from limit_smc_hs in every net namespace */
3353 	smc->limit_smc_hs = net->smc.limit_smc_hs;
3354 
3355 	rc = 0;
3356 	if (!clcsock) {
3357 		rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3358 				      &smc->clcsock);
3359 		if (rc) {
3360 			sk_common_release(sk);
3361 			goto out;
3362 		}
3363 
3364 		/* smc_clcsock_release() does not wait smc->clcsock->sk's
3365 		 * destruction;  its sk_state might not be TCP_CLOSE after
3366 		 * smc->sk is close()d, and TCP timers can be fired later,
3367 		 * which need net ref.
3368 		 */
3369 		sk = smc->clcsock->sk;
3370 		__netns_tracker_free(net, &sk->ns_tracker, false);
3371 		sk->sk_net_refcnt = 1;
3372 		get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
3373 		sock_inuse_add(net, 1);
3374 	} else {
3375 		smc->clcsock = clcsock;
3376 	}
3377 
3378 out:
3379 	return rc;
3380 }
3381 
3382 static int smc_create(struct net *net, struct socket *sock, int protocol,
3383 		      int kern)
3384 {
3385 	return __smc_create(net, sock, protocol, kern, NULL);
3386 }
3387 
3388 static const struct net_proto_family smc_sock_family_ops = {
3389 	.family	= PF_SMC,
3390 	.owner	= THIS_MODULE,
3391 	.create	= smc_create,
3392 };
3393 
3394 static int smc_ulp_init(struct sock *sk)
3395 {
3396 	struct socket *tcp = sk->sk_socket;
3397 	struct net *net = sock_net(sk);
3398 	struct socket *smcsock;
3399 	int protocol, ret;
3400 
3401 	/* only TCP can be replaced */
3402 	if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3403 	    (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3404 		return -ESOCKTNOSUPPORT;
3405 	/* don't handle wq now */
3406 	if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3407 		return -ENOTCONN;
3408 
3409 	if (sk->sk_family == AF_INET)
3410 		protocol = SMCPROTO_SMC;
3411 	else
3412 		protocol = SMCPROTO_SMC6;
3413 
3414 	smcsock = sock_alloc();
3415 	if (!smcsock)
3416 		return -ENFILE;
3417 
3418 	smcsock->type = SOCK_STREAM;
3419 	__module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3420 	ret = __smc_create(net, smcsock, protocol, 1, tcp);
3421 	if (ret) {
3422 		sock_release(smcsock); /* module_put() which ops won't be NULL */
3423 		return ret;
3424 	}
3425 
3426 	/* replace tcp socket to smc */
3427 	smcsock->file = tcp->file;
3428 	smcsock->file->private_data = smcsock;
3429 	smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3430 	smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3431 	tcp->file = NULL;
3432 
3433 	return ret;
3434 }
3435 
3436 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3437 			  const gfp_t priority)
3438 {
3439 	struct inet_connection_sock *icsk = inet_csk(newsk);
3440 
3441 	/* don't inherit ulp ops to child when listen */
3442 	icsk->icsk_ulp_ops = NULL;
3443 }
3444 
3445 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3446 	.name		= "smc",
3447 	.owner		= THIS_MODULE,
3448 	.init		= smc_ulp_init,
3449 	.clone		= smc_ulp_clone,
3450 };
3451 
3452 unsigned int smc_net_id;
3453 
3454 static __net_init int smc_net_init(struct net *net)
3455 {
3456 	int rc;
3457 
3458 	rc = smc_sysctl_net_init(net);
3459 	if (rc)
3460 		return rc;
3461 	return smc_pnet_net_init(net);
3462 }
3463 
3464 static void __net_exit smc_net_exit(struct net *net)
3465 {
3466 	smc_sysctl_net_exit(net);
3467 	smc_pnet_net_exit(net);
3468 }
3469 
3470 static __net_init int smc_net_stat_init(struct net *net)
3471 {
3472 	return smc_stats_init(net);
3473 }
3474 
3475 static void __net_exit smc_net_stat_exit(struct net *net)
3476 {
3477 	smc_stats_exit(net);
3478 }
3479 
3480 static struct pernet_operations smc_net_ops = {
3481 	.init = smc_net_init,
3482 	.exit = smc_net_exit,
3483 	.id   = &smc_net_id,
3484 	.size = sizeof(struct smc_net),
3485 };
3486 
3487 static struct pernet_operations smc_net_stat_ops = {
3488 	.init = smc_net_stat_init,
3489 	.exit = smc_net_stat_exit,
3490 };
3491 
3492 static int __init smc_init(void)
3493 {
3494 	int rc;
3495 
3496 	rc = register_pernet_subsys(&smc_net_ops);
3497 	if (rc)
3498 		return rc;
3499 
3500 	rc = register_pernet_subsys(&smc_net_stat_ops);
3501 	if (rc)
3502 		goto out_pernet_subsys;
3503 
3504 	rc = smc_ism_init();
3505 	if (rc)
3506 		goto out_pernet_subsys_stat;
3507 	smc_clc_init();
3508 
3509 	rc = smc_nl_init();
3510 	if (rc)
3511 		goto out_ism;
3512 
3513 	rc = smc_pnet_init();
3514 	if (rc)
3515 		goto out_nl;
3516 
3517 	rc = -ENOMEM;
3518 
3519 	smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3520 	if (!smc_tcp_ls_wq)
3521 		goto out_pnet;
3522 
3523 	smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3524 	if (!smc_hs_wq)
3525 		goto out_alloc_tcp_ls_wq;
3526 
3527 	smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3528 	if (!smc_close_wq)
3529 		goto out_alloc_hs_wq;
3530 
3531 	rc = smc_core_init();
3532 	if (rc) {
3533 		pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3534 		goto out_alloc_wqs;
3535 	}
3536 
3537 	rc = smc_llc_init();
3538 	if (rc) {
3539 		pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3540 		goto out_core;
3541 	}
3542 
3543 	rc = smc_cdc_init();
3544 	if (rc) {
3545 		pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3546 		goto out_core;
3547 	}
3548 
3549 	rc = proto_register(&smc_proto, 1);
3550 	if (rc) {
3551 		pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3552 		goto out_core;
3553 	}
3554 
3555 	rc = proto_register(&smc_proto6, 1);
3556 	if (rc) {
3557 		pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3558 		goto out_proto;
3559 	}
3560 
3561 	rc = sock_register(&smc_sock_family_ops);
3562 	if (rc) {
3563 		pr_err("%s: sock_register fails with %d\n", __func__, rc);
3564 		goto out_proto6;
3565 	}
3566 	INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3567 	INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3568 
3569 	rc = smc_ib_register_client();
3570 	if (rc) {
3571 		pr_err("%s: ib_register fails with %d\n", __func__, rc);
3572 		goto out_sock;
3573 	}
3574 
3575 	rc = smc_loopback_init();
3576 	if (rc) {
3577 		pr_err("%s: smc_loopback_init fails with %d\n", __func__, rc);
3578 		goto out_ib;
3579 	}
3580 
3581 	rc = tcp_register_ulp(&smc_ulp_ops);
3582 	if (rc) {
3583 		pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3584 		goto out_lo;
3585 	}
3586 
3587 	static_branch_enable(&tcp_have_smc);
3588 	return 0;
3589 
3590 out_lo:
3591 	smc_loopback_exit();
3592 out_ib:
3593 	smc_ib_unregister_client();
3594 out_sock:
3595 	sock_unregister(PF_SMC);
3596 out_proto6:
3597 	proto_unregister(&smc_proto6);
3598 out_proto:
3599 	proto_unregister(&smc_proto);
3600 out_core:
3601 	smc_core_exit();
3602 out_alloc_wqs:
3603 	destroy_workqueue(smc_close_wq);
3604 out_alloc_hs_wq:
3605 	destroy_workqueue(smc_hs_wq);
3606 out_alloc_tcp_ls_wq:
3607 	destroy_workqueue(smc_tcp_ls_wq);
3608 out_pnet:
3609 	smc_pnet_exit();
3610 out_nl:
3611 	smc_nl_exit();
3612 out_ism:
3613 	smc_clc_exit();
3614 	smc_ism_exit();
3615 out_pernet_subsys_stat:
3616 	unregister_pernet_subsys(&smc_net_stat_ops);
3617 out_pernet_subsys:
3618 	unregister_pernet_subsys(&smc_net_ops);
3619 
3620 	return rc;
3621 }
3622 
3623 static void __exit smc_exit(void)
3624 {
3625 	static_branch_disable(&tcp_have_smc);
3626 	tcp_unregister_ulp(&smc_ulp_ops);
3627 	sock_unregister(PF_SMC);
3628 	smc_core_exit();
3629 	smc_loopback_exit();
3630 	smc_ib_unregister_client();
3631 	smc_ism_exit();
3632 	destroy_workqueue(smc_close_wq);
3633 	destroy_workqueue(smc_tcp_ls_wq);
3634 	destroy_workqueue(smc_hs_wq);
3635 	proto_unregister(&smc_proto6);
3636 	proto_unregister(&smc_proto);
3637 	smc_pnet_exit();
3638 	smc_nl_exit();
3639 	smc_clc_exit();
3640 	unregister_pernet_subsys(&smc_net_stat_ops);
3641 	unregister_pernet_subsys(&smc_net_ops);
3642 	rcu_barrier();
3643 }
3644 
3645 module_init(smc_init);
3646 module_exit(smc_exit);
3647 
3648 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3649 MODULE_DESCRIPTION("smc socket address family");
3650 MODULE_LICENSE("GPL");
3651 MODULE_ALIAS_NETPROTO(PF_SMC);
3652 MODULE_ALIAS_TCP_ULP("smc");
3653 MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);
3654