xref: /linux/net/smc/af_smc.c (revision 56d95b0adfa224bb1c67733dbcad30dd8debd39e)
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 #include "smc_inet.h"
58 
59 static DEFINE_MUTEX(smc_server_lgr_pending);	/* serialize link group
60 						 * creation on server
61 						 */
62 static DEFINE_MUTEX(smc_client_lgr_pending);	/* serialize link group
63 						 * creation on client
64 						 */
65 
66 static struct workqueue_struct	*smc_tcp_ls_wq;	/* wq for tcp listen work */
67 struct workqueue_struct	*smc_hs_wq;	/* wq for handshake work */
68 struct workqueue_struct	*smc_close_wq;	/* wq for close work */
69 
70 static void smc_tcp_listen_work(struct work_struct *);
71 static void smc_connect_work(struct work_struct *);
72 
73 int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb)
74 {
75 	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
76 	void *hdr;
77 
78 	if (cb_ctx->pos[0])
79 		goto out;
80 
81 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
82 			  &smc_gen_nl_family, NLM_F_MULTI,
83 			  SMC_NETLINK_DUMP_HS_LIMITATION);
84 	if (!hdr)
85 		return -ENOMEM;
86 
87 	if (nla_put_u8(skb, SMC_NLA_HS_LIMITATION_ENABLED,
88 		       sock_net(skb->sk)->smc.limit_smc_hs))
89 		goto err;
90 
91 	genlmsg_end(skb, hdr);
92 	cb_ctx->pos[0] = 1;
93 out:
94 	return skb->len;
95 err:
96 	genlmsg_cancel(skb, hdr);
97 	return -EMSGSIZE;
98 }
99 
100 int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
101 {
102 	sock_net(skb->sk)->smc.limit_smc_hs = true;
103 	return 0;
104 }
105 
106 int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
107 {
108 	sock_net(skb->sk)->smc.limit_smc_hs = false;
109 	return 0;
110 }
111 
112 static void smc_set_keepalive(struct sock *sk, int val)
113 {
114 	struct smc_sock *smc = smc_sk(sk);
115 
116 	smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
117 }
118 
119 static struct sock *smc_tcp_syn_recv_sock(const struct sock *sk,
120 					  struct sk_buff *skb,
121 					  struct request_sock *req,
122 					  struct dst_entry *dst,
123 					  struct request_sock *req_unhash,
124 					  bool *own_req)
125 {
126 	struct smc_sock *smc;
127 	struct sock *child;
128 
129 	smc = smc_clcsock_user_data(sk);
130 
131 	if (READ_ONCE(sk->sk_ack_backlog) + atomic_read(&smc->queued_smc_hs) >
132 				sk->sk_max_ack_backlog)
133 		goto drop;
134 
135 	if (sk_acceptq_is_full(&smc->sk)) {
136 		NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
137 		goto drop;
138 	}
139 
140 	/* passthrough to original syn recv sock fct */
141 	child = smc->ori_af_ops->syn_recv_sock(sk, skb, req, dst, req_unhash,
142 					       own_req);
143 	/* child must not inherit smc or its ops */
144 	if (child) {
145 		rcu_assign_sk_user_data(child, NULL);
146 
147 		/* v4-mapped sockets don't inherit parent ops. Don't restore. */
148 		if (inet_csk(child)->icsk_af_ops == inet_csk(sk)->icsk_af_ops)
149 			inet_csk(child)->icsk_af_ops = smc->ori_af_ops;
150 	}
151 	return child;
152 
153 drop:
154 	dst_release(dst);
155 	tcp_listendrop(sk);
156 	return NULL;
157 }
158 
159 static bool smc_hs_congested(const struct sock *sk)
160 {
161 	const struct smc_sock *smc;
162 
163 	smc = smc_clcsock_user_data(sk);
164 
165 	if (!smc)
166 		return true;
167 
168 	if (workqueue_congested(WORK_CPU_UNBOUND, smc_hs_wq))
169 		return true;
170 
171 	return false;
172 }
173 
174 struct smc_hashinfo smc_v4_hashinfo = {
175 	.lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
176 };
177 
178 struct smc_hashinfo smc_v6_hashinfo = {
179 	.lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
180 };
181 
182 int smc_hash_sk(struct sock *sk)
183 {
184 	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
185 	struct hlist_head *head;
186 
187 	head = &h->ht;
188 
189 	write_lock_bh(&h->lock);
190 	sk_add_node(sk, head);
191 	write_unlock_bh(&h->lock);
192 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
193 
194 	return 0;
195 }
196 
197 void smc_unhash_sk(struct sock *sk)
198 {
199 	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
200 
201 	write_lock_bh(&h->lock);
202 	if (sk_del_node_init(sk))
203 		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
204 	write_unlock_bh(&h->lock);
205 }
206 
207 /* This will be called before user really release sock_lock. So do the
208  * work which we didn't do because of user hold the sock_lock in the
209  * BH context
210  */
211 void smc_release_cb(struct sock *sk)
212 {
213 	struct smc_sock *smc = smc_sk(sk);
214 
215 	if (smc->conn.tx_in_release_sock) {
216 		smc_tx_pending(&smc->conn);
217 		smc->conn.tx_in_release_sock = false;
218 	}
219 }
220 
221 struct proto smc_proto = {
222 	.name		= "SMC",
223 	.owner		= THIS_MODULE,
224 	.keepalive	= smc_set_keepalive,
225 	.hash		= smc_hash_sk,
226 	.unhash		= smc_unhash_sk,
227 	.release_cb	= smc_release_cb,
228 	.obj_size	= sizeof(struct smc_sock),
229 	.h.smc_hash	= &smc_v4_hashinfo,
230 	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
231 };
232 EXPORT_SYMBOL_GPL(smc_proto);
233 
234 struct proto smc_proto6 = {
235 	.name		= "SMC6",
236 	.owner		= THIS_MODULE,
237 	.keepalive	= smc_set_keepalive,
238 	.hash		= smc_hash_sk,
239 	.unhash		= smc_unhash_sk,
240 	.release_cb	= smc_release_cb,
241 	.obj_size	= sizeof(struct smc_sock),
242 	.h.smc_hash	= &smc_v6_hashinfo,
243 	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
244 };
245 EXPORT_SYMBOL_GPL(smc_proto6);
246 
247 static void smc_fback_restore_callbacks(struct smc_sock *smc)
248 {
249 	struct sock *clcsk = smc->clcsock->sk;
250 
251 	write_lock_bh(&clcsk->sk_callback_lock);
252 	clcsk->sk_user_data = NULL;
253 
254 	smc_clcsock_restore_cb(&clcsk->sk_state_change, &smc->clcsk_state_change);
255 	smc_clcsock_restore_cb(&clcsk->sk_data_ready, &smc->clcsk_data_ready);
256 	smc_clcsock_restore_cb(&clcsk->sk_write_space, &smc->clcsk_write_space);
257 	smc_clcsock_restore_cb(&clcsk->sk_error_report, &smc->clcsk_error_report);
258 
259 	write_unlock_bh(&clcsk->sk_callback_lock);
260 }
261 
262 static void smc_restore_fallback_changes(struct smc_sock *smc)
263 {
264 	if (smc->clcsock->file) { /* non-accepted sockets have no file yet */
265 		smc->clcsock->file->private_data = smc->sk.sk_socket;
266 		smc->clcsock->file = NULL;
267 		smc_fback_restore_callbacks(smc);
268 	}
269 }
270 
271 static int __smc_release(struct smc_sock *smc)
272 {
273 	struct sock *sk = &smc->sk;
274 	int rc = 0;
275 
276 	if (!smc->use_fallback) {
277 		rc = smc_close_active(smc);
278 		smc_sock_set_flag(sk, SOCK_DEAD);
279 		sk->sk_shutdown |= SHUTDOWN_MASK;
280 	} else {
281 		if (sk->sk_state != SMC_CLOSED) {
282 			if (sk->sk_state != SMC_LISTEN &&
283 			    sk->sk_state != SMC_INIT)
284 				sock_put(sk); /* passive closing */
285 			if (sk->sk_state == SMC_LISTEN) {
286 				/* wake up clcsock accept */
287 				rc = kernel_sock_shutdown(smc->clcsock,
288 							  SHUT_RDWR);
289 			}
290 			sk->sk_state = SMC_CLOSED;
291 			sk->sk_state_change(sk);
292 		}
293 		smc_restore_fallback_changes(smc);
294 	}
295 
296 	sk->sk_prot->unhash(sk);
297 
298 	if (sk->sk_state == SMC_CLOSED) {
299 		if (smc->clcsock) {
300 			release_sock(sk);
301 			smc_clcsock_release(smc);
302 			lock_sock(sk);
303 		}
304 		if (!smc->use_fallback)
305 			smc_conn_free(&smc->conn);
306 	}
307 
308 	return rc;
309 }
310 
311 int smc_release(struct socket *sock)
312 {
313 	struct sock *sk = sock->sk;
314 	struct smc_sock *smc;
315 	int old_state, rc = 0;
316 
317 	if (!sk)
318 		goto out;
319 
320 	sock_hold(sk); /* sock_put below */
321 	smc = smc_sk(sk);
322 
323 	old_state = sk->sk_state;
324 
325 	/* cleanup for a dangling non-blocking connect */
326 	if (smc->connect_nonblock && old_state == SMC_INIT)
327 		tcp_abort(smc->clcsock->sk, ECONNABORTED);
328 
329 	if (cancel_work_sync(&smc->connect_work))
330 		sock_put(&smc->sk); /* sock_hold in smc_connect for passive closing */
331 
332 	if (sk->sk_state == SMC_LISTEN)
333 		/* smc_close_non_accepted() is called and acquires
334 		 * sock lock for child sockets again
335 		 */
336 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
337 	else
338 		lock_sock(sk);
339 
340 	if (old_state == SMC_INIT && sk->sk_state == SMC_ACTIVE &&
341 	    !smc->use_fallback)
342 		smc_close_active_abort(smc);
343 
344 	rc = __smc_release(smc);
345 
346 	/* detach socket */
347 	sock_orphan(sk);
348 	sock->sk = NULL;
349 	release_sock(sk);
350 
351 	sock_put(sk); /* sock_hold above */
352 	sock_put(sk); /* final sock_put */
353 out:
354 	return rc;
355 }
356 
357 static void smc_destruct(struct sock *sk)
358 {
359 	if (sk->sk_state != SMC_CLOSED)
360 		return;
361 	if (!sock_flag(sk, SOCK_DEAD))
362 		return;
363 }
364 
365 void smc_sk_init(struct net *net, struct sock *sk, int protocol)
366 {
367 	struct smc_sock *smc = smc_sk(sk);
368 
369 	sk->sk_state = SMC_INIT;
370 	sk->sk_destruct = smc_destruct;
371 	sk->sk_protocol = protocol;
372 	WRITE_ONCE(sk->sk_sndbuf, 2 * READ_ONCE(net->smc.sysctl_wmem));
373 	WRITE_ONCE(sk->sk_rcvbuf, 2 * READ_ONCE(net->smc.sysctl_rmem));
374 	INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
375 	INIT_WORK(&smc->connect_work, smc_connect_work);
376 	INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
377 	INIT_LIST_HEAD(&smc->accept_q);
378 	spin_lock_init(&smc->accept_q_lock);
379 	spin_lock_init(&smc->conn.send_lock);
380 	sk->sk_prot->hash(sk);
381 	mutex_init(&smc->clcsock_release_lock);
382 	smc_init_saved_callbacks(smc);
383 	smc->limit_smc_hs = net->smc.limit_smc_hs;
384 	smc->use_fallback = false; /* assume rdma capability first */
385 	smc->fallback_rsn = 0;
386 	smc_close_init(smc);
387 }
388 
389 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
390 				   int protocol)
391 {
392 	struct proto *prot;
393 	struct sock *sk;
394 
395 	prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
396 	sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
397 	if (!sk)
398 		return NULL;
399 
400 	sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
401 	smc_sk_init(net, sk, protocol);
402 
403 	return sk;
404 }
405 
406 int smc_bind(struct socket *sock, struct sockaddr *uaddr,
407 	     int addr_len)
408 {
409 	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
410 	struct sock *sk = sock->sk;
411 	struct smc_sock *smc;
412 	int rc;
413 
414 	smc = smc_sk(sk);
415 
416 	/* replicate tests from inet_bind(), to be safe wrt. future changes */
417 	rc = -EINVAL;
418 	if (addr_len < sizeof(struct sockaddr_in))
419 		goto out;
420 
421 	rc = -EAFNOSUPPORT;
422 	if (addr->sin_family != AF_INET &&
423 	    addr->sin_family != AF_INET6 &&
424 	    addr->sin_family != AF_UNSPEC)
425 		goto out;
426 	/* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
427 	if (addr->sin_family == AF_UNSPEC &&
428 	    addr->sin_addr.s_addr != htonl(INADDR_ANY))
429 		goto out;
430 
431 	lock_sock(sk);
432 
433 	/* Check if socket is already active */
434 	rc = -EINVAL;
435 	if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
436 		goto out_rel;
437 
438 	smc->clcsock->sk->sk_reuse = sk->sk_reuse;
439 	smc->clcsock->sk->sk_reuseport = sk->sk_reuseport;
440 	rc = kernel_bind(smc->clcsock, uaddr, addr_len);
441 
442 out_rel:
443 	release_sock(sk);
444 out:
445 	return rc;
446 }
447 
448 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
449  * clc socket (since smc is not called for these options from net/core)
450  */
451 
452 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
453 			     (1UL << SOCK_KEEPOPEN) | \
454 			     (1UL << SOCK_LINGER) | \
455 			     (1UL << SOCK_BROADCAST) | \
456 			     (1UL << SOCK_TIMESTAMP) | \
457 			     (1UL << SOCK_DBG) | \
458 			     (1UL << SOCK_RCVTSTAMP) | \
459 			     (1UL << SOCK_RCVTSTAMPNS) | \
460 			     (1UL << SOCK_LOCALROUTE) | \
461 			     (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
462 			     (1UL << SOCK_RXQ_OVFL) | \
463 			     (1UL << SOCK_WIFI_STATUS) | \
464 			     (1UL << SOCK_NOFCS) | \
465 			     (1UL << SOCK_FILTER_LOCKED) | \
466 			     (1UL << SOCK_TSTAMP_NEW))
467 
468 /* if set, use value set by setsockopt() - else use IPv4 or SMC sysctl value */
469 static void smc_adjust_sock_bufsizes(struct sock *nsk, struct sock *osk,
470 				     unsigned long mask)
471 {
472 	nsk->sk_userlocks = osk->sk_userlocks;
473 	if (osk->sk_userlocks & SOCK_SNDBUF_LOCK)
474 		nsk->sk_sndbuf = osk->sk_sndbuf;
475 	if (osk->sk_userlocks & SOCK_RCVBUF_LOCK)
476 		nsk->sk_rcvbuf = osk->sk_rcvbuf;
477 }
478 
479 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
480 				   unsigned long mask)
481 {
482 	/* options we don't get control via setsockopt for */
483 	nsk->sk_type = osk->sk_type;
484 	nsk->sk_sndtimeo = osk->sk_sndtimeo;
485 	nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
486 	nsk->sk_mark = READ_ONCE(osk->sk_mark);
487 	nsk->sk_priority = READ_ONCE(osk->sk_priority);
488 	nsk->sk_rcvlowat = osk->sk_rcvlowat;
489 	nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
490 	nsk->sk_err = osk->sk_err;
491 
492 	nsk->sk_flags &= ~mask;
493 	nsk->sk_flags |= osk->sk_flags & mask;
494 
495 	smc_adjust_sock_bufsizes(nsk, osk, mask);
496 }
497 
498 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
499 {
500 	smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
501 }
502 
503 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
504 			     (1UL << SOCK_KEEPOPEN) | \
505 			     (1UL << SOCK_LINGER) | \
506 			     (1UL << SOCK_DBG))
507 /* copy only settings and flags relevant for smc from clc to smc socket */
508 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
509 {
510 	smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
511 }
512 
513 /* register the new vzalloced sndbuf on all links */
514 static int smcr_lgr_reg_sndbufs(struct smc_link *link,
515 				struct smc_buf_desc *snd_desc)
516 {
517 	struct smc_link_group *lgr = link->lgr;
518 	int i, rc = 0;
519 
520 	if (!snd_desc->is_vm)
521 		return -EINVAL;
522 
523 	/* protect against parallel smcr_link_reg_buf() */
524 	down_write(&lgr->llc_conf_mutex);
525 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
526 		if (!smc_link_active(&lgr->lnk[i]))
527 			continue;
528 		rc = smcr_link_reg_buf(&lgr->lnk[i], snd_desc);
529 		if (rc)
530 			break;
531 	}
532 	up_write(&lgr->llc_conf_mutex);
533 	return rc;
534 }
535 
536 /* register the new rmb on all links */
537 static int smcr_lgr_reg_rmbs(struct smc_link *link,
538 			     struct smc_buf_desc *rmb_desc)
539 {
540 	struct smc_link_group *lgr = link->lgr;
541 	bool do_slow = false;
542 	int i, rc = 0;
543 
544 	rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
545 	if (rc)
546 		return rc;
547 
548 	down_read(&lgr->llc_conf_mutex);
549 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
550 		if (!smc_link_active(&lgr->lnk[i]))
551 			continue;
552 		if (!rmb_desc->is_reg_mr[link->link_idx]) {
553 			up_read(&lgr->llc_conf_mutex);
554 			goto slow_path;
555 		}
556 	}
557 	/* mr register already */
558 	goto fast_path;
559 slow_path:
560 	do_slow = true;
561 	/* protect against parallel smc_llc_cli_rkey_exchange() and
562 	 * parallel smcr_link_reg_buf()
563 	 */
564 	down_write(&lgr->llc_conf_mutex);
565 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
566 		if (!smc_link_active(&lgr->lnk[i]))
567 			continue;
568 		rc = smcr_link_reg_buf(&lgr->lnk[i], rmb_desc);
569 		if (rc)
570 			goto out;
571 	}
572 fast_path:
573 	/* exchange confirm_rkey msg with peer */
574 	rc = smc_llc_do_confirm_rkey(link, rmb_desc);
575 	if (rc) {
576 		rc = -EFAULT;
577 		goto out;
578 	}
579 	rmb_desc->is_conf_rkey = true;
580 out:
581 	do_slow ? up_write(&lgr->llc_conf_mutex) : up_read(&lgr->llc_conf_mutex);
582 	smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
583 	return rc;
584 }
585 
586 static int smcr_clnt_conf_first_link(struct smc_sock *smc)
587 {
588 	struct smc_link *link = smc->conn.lnk;
589 	struct smc_llc_qentry *qentry;
590 	int rc;
591 
592 	/* Receive CONFIRM LINK request from server over RoCE fabric.
593 	 * Increasing the client's timeout by twice as much as the server's
594 	 * timeout by default can temporarily avoid decline messages of
595 	 * both sides crossing or colliding
596 	 */
597 	qentry = smc_llc_wait(link->lgr, NULL, 2 * SMC_LLC_WAIT_TIME,
598 			      SMC_LLC_CONFIRM_LINK);
599 	if (!qentry) {
600 		struct smc_clc_msg_decline dclc;
601 
602 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
603 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
604 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
605 	}
606 	smc_llc_save_peer_uid(qentry);
607 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
608 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
609 	if (rc)
610 		return SMC_CLC_DECL_RMBE_EC;
611 
612 	rc = smc_ib_modify_qp_rts(link);
613 	if (rc)
614 		return SMC_CLC_DECL_ERR_RDYLNK;
615 
616 	smc_wr_remember_qp_attr(link);
617 
618 	/* reg the sndbuf if it was vzalloced */
619 	if (smc->conn.sndbuf_desc->is_vm) {
620 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
621 			return SMC_CLC_DECL_ERR_REGBUF;
622 	}
623 
624 	/* reg the rmb */
625 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
626 		return SMC_CLC_DECL_ERR_REGBUF;
627 
628 	/* confirm_rkey is implicit on 1st contact */
629 	smc->conn.rmb_desc->is_conf_rkey = true;
630 
631 	/* send CONFIRM LINK response over RoCE fabric */
632 	rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
633 	if (rc < 0)
634 		return SMC_CLC_DECL_TIMEOUT_CL;
635 
636 	smc_llc_link_active(link);
637 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
638 
639 	if (link->lgr->max_links > 1) {
640 		/* optional 2nd link, receive ADD LINK request from server */
641 		qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
642 				      SMC_LLC_ADD_LINK);
643 		if (!qentry) {
644 			struct smc_clc_msg_decline dclc;
645 
646 			rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
647 					      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
648 			if (rc == -EAGAIN)
649 				rc = 0; /* no DECLINE received, go with one link */
650 			return rc;
651 		}
652 		smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
653 		smc_llc_cli_add_link(link, qentry);
654 	}
655 	return 0;
656 }
657 
658 static bool smc_isascii(char *hostname)
659 {
660 	int i;
661 
662 	for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
663 		if (!isascii(hostname[i]))
664 			return false;
665 	return true;
666 }
667 
668 static void smc_conn_save_peer_info_fce(struct smc_sock *smc,
669 					struct smc_clc_msg_accept_confirm *clc)
670 {
671 	struct smc_clc_first_contact_ext *fce;
672 	int clc_v2_len;
673 
674 	if (clc->hdr.version == SMC_V1 ||
675 	    !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
676 		return;
677 
678 	if (smc->conn.lgr->is_smcd) {
679 		memcpy(smc->conn.lgr->negotiated_eid, clc->d1.eid,
680 		       SMC_MAX_EID_LEN);
681 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm, d1);
682 	} else {
683 		memcpy(smc->conn.lgr->negotiated_eid, clc->r1.eid,
684 		       SMC_MAX_EID_LEN);
685 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm, r1);
686 	}
687 	fce = (struct smc_clc_first_contact_ext *)(((u8 *)clc) + clc_v2_len);
688 	smc->conn.lgr->peer_os = fce->os_type;
689 	smc->conn.lgr->peer_smc_release = fce->release;
690 	if (smc_isascii(fce->hostname))
691 		memcpy(smc->conn.lgr->peer_hostname, fce->hostname,
692 		       SMC_MAX_HOSTNAME_LEN);
693 }
694 
695 static void smcr_conn_save_peer_info(struct smc_sock *smc,
696 				     struct smc_clc_msg_accept_confirm *clc)
697 {
698 	int bufsize = smc_uncompress_bufsize(clc->r0.rmbe_size);
699 
700 	smc->conn.peer_rmbe_idx = clc->r0.rmbe_idx;
701 	smc->conn.local_tx_ctrl.token = ntohl(clc->r0.rmbe_alert_token);
702 	smc->conn.peer_rmbe_size = bufsize;
703 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
704 	smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
705 }
706 
707 static void smcd_conn_save_peer_info(struct smc_sock *smc,
708 				     struct smc_clc_msg_accept_confirm *clc)
709 {
710 	int bufsize = smc_uncompress_bufsize(clc->d0.dmbe_size);
711 
712 	smc->conn.peer_rmbe_idx = clc->d0.dmbe_idx;
713 	smc->conn.peer_token = ntohll(clc->d0.token);
714 	/* msg header takes up space in the buffer */
715 	smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
716 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
717 	smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
718 }
719 
720 static void smc_conn_save_peer_info(struct smc_sock *smc,
721 				    struct smc_clc_msg_accept_confirm *clc)
722 {
723 	if (smc->conn.lgr->is_smcd)
724 		smcd_conn_save_peer_info(smc, clc);
725 	else
726 		smcr_conn_save_peer_info(smc, clc);
727 	smc_conn_save_peer_info_fce(smc, clc);
728 }
729 
730 static void smc_link_save_peer_info(struct smc_link *link,
731 				    struct smc_clc_msg_accept_confirm *clc,
732 				    struct smc_init_info *ini)
733 {
734 	link->peer_qpn = ntoh24(clc->r0.qpn);
735 	memcpy(link->peer_gid, ini->peer_gid, SMC_GID_SIZE);
736 	memcpy(link->peer_mac, ini->peer_mac, sizeof(link->peer_mac));
737 	link->peer_psn = ntoh24(clc->r0.psn);
738 	link->peer_mtu = clc->r0.qp_mtu;
739 }
740 
741 static void smc_stat_inc_fback_rsn_cnt(struct smc_sock *smc,
742 				       struct smc_stats_fback *fback_arr)
743 {
744 	int cnt;
745 
746 	for (cnt = 0; cnt < SMC_MAX_FBACK_RSN_CNT; cnt++) {
747 		if (fback_arr[cnt].fback_code == smc->fallback_rsn) {
748 			fback_arr[cnt].count++;
749 			break;
750 		}
751 		if (!fback_arr[cnt].fback_code) {
752 			fback_arr[cnt].fback_code = smc->fallback_rsn;
753 			fback_arr[cnt].count++;
754 			break;
755 		}
756 	}
757 }
758 
759 static void smc_stat_fallback(struct smc_sock *smc)
760 {
761 	struct net *net = sock_net(&smc->sk);
762 
763 	mutex_lock(&net->smc.mutex_fback_rsn);
764 	if (smc->listen_smc) {
765 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->srv);
766 		net->smc.fback_rsn->srv_fback_cnt++;
767 	} else {
768 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->clnt);
769 		net->smc.fback_rsn->clnt_fback_cnt++;
770 	}
771 	mutex_unlock(&net->smc.mutex_fback_rsn);
772 }
773 
774 /* must be called under rcu read lock */
775 static void smc_fback_wakeup_waitqueue(struct smc_sock *smc, void *key)
776 {
777 	struct socket_wq *wq;
778 	__poll_t flags;
779 
780 	wq = rcu_dereference(smc->sk.sk_wq);
781 	if (!skwq_has_sleeper(wq))
782 		return;
783 
784 	/* wake up smc sk->sk_wq */
785 	if (!key) {
786 		/* sk_state_change */
787 		wake_up_interruptible_all(&wq->wait);
788 	} else {
789 		flags = key_to_poll(key);
790 		if (flags & (EPOLLIN | EPOLLOUT))
791 			/* sk_data_ready or sk_write_space */
792 			wake_up_interruptible_sync_poll(&wq->wait, flags);
793 		else if (flags & EPOLLERR)
794 			/* sk_error_report */
795 			wake_up_interruptible_poll(&wq->wait, flags);
796 	}
797 }
798 
799 static int smc_fback_mark_woken(wait_queue_entry_t *wait,
800 				unsigned int mode, int sync, void *key)
801 {
802 	struct smc_mark_woken *mark =
803 		container_of(wait, struct smc_mark_woken, wait_entry);
804 
805 	mark->woken = true;
806 	mark->key = key;
807 	return 0;
808 }
809 
810 static void smc_fback_forward_wakeup(struct smc_sock *smc, struct sock *clcsk,
811 				     void (*clcsock_callback)(struct sock *sk))
812 {
813 	struct smc_mark_woken mark = { .woken = false };
814 	struct socket_wq *wq;
815 
816 	init_waitqueue_func_entry(&mark.wait_entry,
817 				  smc_fback_mark_woken);
818 	rcu_read_lock();
819 	wq = rcu_dereference(clcsk->sk_wq);
820 	if (!wq)
821 		goto out;
822 	add_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
823 	clcsock_callback(clcsk);
824 	remove_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
825 
826 	if (mark.woken)
827 		smc_fback_wakeup_waitqueue(smc, mark.key);
828 out:
829 	rcu_read_unlock();
830 }
831 
832 static void smc_fback_state_change(struct sock *clcsk)
833 {
834 	struct smc_sock *smc;
835 
836 	read_lock_bh(&clcsk->sk_callback_lock);
837 	smc = smc_clcsock_user_data(clcsk);
838 	if (smc)
839 		smc_fback_forward_wakeup(smc, clcsk,
840 					 smc->clcsk_state_change);
841 	read_unlock_bh(&clcsk->sk_callback_lock);
842 }
843 
844 static void smc_fback_data_ready(struct sock *clcsk)
845 {
846 	struct smc_sock *smc;
847 
848 	read_lock_bh(&clcsk->sk_callback_lock);
849 	smc = smc_clcsock_user_data(clcsk);
850 	if (smc)
851 		smc_fback_forward_wakeup(smc, clcsk,
852 					 smc->clcsk_data_ready);
853 	read_unlock_bh(&clcsk->sk_callback_lock);
854 }
855 
856 static void smc_fback_write_space(struct sock *clcsk)
857 {
858 	struct smc_sock *smc;
859 
860 	read_lock_bh(&clcsk->sk_callback_lock);
861 	smc = smc_clcsock_user_data(clcsk);
862 	if (smc)
863 		smc_fback_forward_wakeup(smc, clcsk,
864 					 smc->clcsk_write_space);
865 	read_unlock_bh(&clcsk->sk_callback_lock);
866 }
867 
868 static void smc_fback_error_report(struct sock *clcsk)
869 {
870 	struct smc_sock *smc;
871 
872 	read_lock_bh(&clcsk->sk_callback_lock);
873 	smc = smc_clcsock_user_data(clcsk);
874 	if (smc)
875 		smc_fback_forward_wakeup(smc, clcsk,
876 					 smc->clcsk_error_report);
877 	read_unlock_bh(&clcsk->sk_callback_lock);
878 }
879 
880 static void smc_fback_replace_callbacks(struct smc_sock *smc)
881 {
882 	struct sock *clcsk = smc->clcsock->sk;
883 
884 	write_lock_bh(&clcsk->sk_callback_lock);
885 	clcsk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
886 
887 	smc_clcsock_replace_cb(&clcsk->sk_state_change, smc_fback_state_change,
888 			       &smc->clcsk_state_change);
889 	smc_clcsock_replace_cb(&clcsk->sk_data_ready, smc_fback_data_ready,
890 			       &smc->clcsk_data_ready);
891 	smc_clcsock_replace_cb(&clcsk->sk_write_space, smc_fback_write_space,
892 			       &smc->clcsk_write_space);
893 	smc_clcsock_replace_cb(&clcsk->sk_error_report, smc_fback_error_report,
894 			       &smc->clcsk_error_report);
895 
896 	write_unlock_bh(&clcsk->sk_callback_lock);
897 }
898 
899 static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code)
900 {
901 	int rc = 0;
902 
903 	mutex_lock(&smc->clcsock_release_lock);
904 	if (!smc->clcsock) {
905 		rc = -EBADF;
906 		goto out;
907 	}
908 
909 	smc->use_fallback = true;
910 	smc->fallback_rsn = reason_code;
911 	smc_stat_fallback(smc);
912 	trace_smc_switch_to_fallback(smc, reason_code);
913 	if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
914 		smc->clcsock->file = smc->sk.sk_socket->file;
915 		smc->clcsock->file->private_data = smc->clcsock;
916 		smc->clcsock->wq.fasync_list =
917 			smc->sk.sk_socket->wq.fasync_list;
918 		smc->sk.sk_socket->wq.fasync_list = NULL;
919 
920 		/* There might be some wait entries remaining
921 		 * in smc sk->sk_wq and they should be woken up
922 		 * as clcsock's wait queue is woken up.
923 		 */
924 		smc_fback_replace_callbacks(smc);
925 	}
926 out:
927 	mutex_unlock(&smc->clcsock_release_lock);
928 	return rc;
929 }
930 
931 /* fall back during connect */
932 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
933 {
934 	struct net *net = sock_net(&smc->sk);
935 	int rc = 0;
936 
937 	rc = smc_switch_to_fallback(smc, reason_code);
938 	if (rc) { /* fallback fails */
939 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
940 		if (smc->sk.sk_state == SMC_INIT)
941 			sock_put(&smc->sk); /* passive closing */
942 		return rc;
943 	}
944 	smc_copy_sock_settings_to_clc(smc);
945 	smc->connect_nonblock = 0;
946 	if (smc->sk.sk_state == SMC_INIT)
947 		smc->sk.sk_state = SMC_ACTIVE;
948 	return 0;
949 }
950 
951 /* decline and fall back during connect */
952 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
953 					u8 version)
954 {
955 	struct net *net = sock_net(&smc->sk);
956 	int rc;
957 
958 	if (reason_code < 0) { /* error, fallback is not possible */
959 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
960 		if (smc->sk.sk_state == SMC_INIT)
961 			sock_put(&smc->sk); /* passive closing */
962 		return reason_code;
963 	}
964 	if (reason_code != SMC_CLC_DECL_PEERDECL) {
965 		rc = smc_clc_send_decline(smc, reason_code, version);
966 		if (rc < 0) {
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 rc;
971 		}
972 	}
973 	return smc_connect_fallback(smc, reason_code);
974 }
975 
976 static void smc_conn_abort(struct smc_sock *smc, int local_first)
977 {
978 	struct smc_connection *conn = &smc->conn;
979 	struct smc_link_group *lgr = conn->lgr;
980 	bool lgr_valid = false;
981 
982 	if (smc_conn_lgr_valid(conn))
983 		lgr_valid = true;
984 
985 	smc_conn_free(conn);
986 	if (local_first && lgr_valid)
987 		smc_lgr_cleanup_early(lgr);
988 }
989 
990 /* check if there is a rdma device available for this connection. */
991 /* called for connect and listen */
992 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
993 {
994 	/* PNET table look up: search active ib_device and port
995 	 * within same PNETID that also contains the ethernet device
996 	 * used for the internal TCP socket
997 	 */
998 	smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
999 	if (!ini->check_smcrv2 && !ini->ib_dev)
1000 		return SMC_CLC_DECL_NOSMCRDEV;
1001 	if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
1002 		return SMC_CLC_DECL_NOSMCRDEV;
1003 	return 0;
1004 }
1005 
1006 /* check if there is an ISM device available for this connection. */
1007 /* called for connect and listen */
1008 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
1009 {
1010 	/* Find ISM device with same PNETID as connecting interface  */
1011 	smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
1012 	if (!ini->ism_dev[0])
1013 		return SMC_CLC_DECL_NOSMCDDEV;
1014 	else
1015 		ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
1016 	return 0;
1017 }
1018 
1019 /* is chid unique for the ism devices that are already determined? */
1020 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
1021 					   int cnt)
1022 {
1023 	int i = (!ini->ism_dev[0]) ? 1 : 0;
1024 
1025 	for (; i < cnt; i++)
1026 		if (ini->ism_chid[i] == chid)
1027 			return false;
1028 	return true;
1029 }
1030 
1031 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
1032  * PNETID matching net_device)
1033  */
1034 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
1035 				       struct smc_init_info *ini)
1036 {
1037 	int rc = SMC_CLC_DECL_NOSMCDDEV;
1038 	struct smcd_dev *smcd;
1039 	int i = 1, entry = 1;
1040 	bool is_emulated;
1041 	u16 chid;
1042 
1043 	if (smcd_indicated(ini->smc_type_v1))
1044 		rc = 0;		/* already initialized for V1 */
1045 	mutex_lock(&smcd_dev_list.mutex);
1046 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1047 		if (smcd->going_away || smcd == ini->ism_dev[0])
1048 			continue;
1049 		chid = smc_ism_get_chid(smcd);
1050 		if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
1051 			continue;
1052 		is_emulated = __smc_ism_is_emulated(chid);
1053 		if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
1054 		    smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
1055 			if (is_emulated && entry == SMCD_CLC_MAX_V2_GID_ENTRIES)
1056 				/* It's the last GID-CHID entry left in CLC
1057 				 * Proposal SMC-Dv2 extension, but an Emulated-
1058 				 * ISM device will take two entries. So give
1059 				 * up it and try the next potential ISM device.
1060 				 */
1061 				continue;
1062 			ini->ism_dev[i] = smcd;
1063 			ini->ism_chid[i] = chid;
1064 			ini->is_smcd = true;
1065 			rc = 0;
1066 			i++;
1067 			entry = is_emulated ? entry + 2 : entry + 1;
1068 			if (entry > SMCD_CLC_MAX_V2_GID_ENTRIES)
1069 				break;
1070 		}
1071 	}
1072 	mutex_unlock(&smcd_dev_list.mutex);
1073 	ini->ism_offered_cnt = i - 1;
1074 	if (!ini->ism_dev[0] && !ini->ism_dev[1])
1075 		ini->smcd_version = 0;
1076 
1077 	return rc;
1078 }
1079 
1080 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
1081 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
1082 				      struct smc_init_info *ini)
1083 {
1084 	if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
1085 		return SMC_CLC_DECL_ISMVLANERR;
1086 	return 0;
1087 }
1088 
1089 static int smc_find_proposal_devices(struct smc_sock *smc,
1090 				     struct smc_init_info *ini)
1091 {
1092 	int rc = 0;
1093 
1094 	/* check if there is an ism device available */
1095 	if (!(ini->smcd_version & SMC_V1) ||
1096 	    smc_find_ism_device(smc, ini) ||
1097 	    smc_connect_ism_vlan_setup(smc, ini))
1098 		ini->smcd_version &= ~SMC_V1;
1099 	/* else ISM V1 is supported for this connection */
1100 
1101 	/* check if there is an rdma device available */
1102 	if (!(ini->smcr_version & SMC_V1) ||
1103 	    smc_find_rdma_device(smc, ini))
1104 		ini->smcr_version &= ~SMC_V1;
1105 	/* else RDMA is supported for this connection */
1106 
1107 	ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
1108 					      ini->smcr_version & SMC_V1);
1109 
1110 	/* check if there is an ism v2 device available */
1111 	if (!(ini->smcd_version & SMC_V2) ||
1112 	    !smc_ism_is_v2_capable() ||
1113 	    smc_find_ism_v2_device_clnt(smc, ini))
1114 		ini->smcd_version &= ~SMC_V2;
1115 
1116 	/* check if there is an rdma v2 device available */
1117 	ini->check_smcrv2 = true;
1118 	ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
1119 	if (!(ini->smcr_version & SMC_V2) ||
1120 #if IS_ENABLED(CONFIG_IPV6)
1121 	    (smc->clcsock->sk->sk_family == AF_INET6 &&
1122 	     !ipv6_addr_v4mapped(&smc->clcsock->sk->sk_v6_rcv_saddr)) ||
1123 #endif
1124 	    !smc_clc_ueid_count() ||
1125 	    smc_find_rdma_device(smc, ini))
1126 		ini->smcr_version &= ~SMC_V2;
1127 	ini->check_smcrv2 = false;
1128 
1129 	ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
1130 					      ini->smcr_version & SMC_V2);
1131 
1132 	/* if neither ISM nor RDMA are supported, fallback */
1133 	if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
1134 		rc = SMC_CLC_DECL_NOSMCDEV;
1135 
1136 	return rc;
1137 }
1138 
1139 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
1140  * used, the VLAN ID will be registered again during the connection setup.
1141  */
1142 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
1143 					struct smc_init_info *ini)
1144 {
1145 	if (!smcd_indicated(ini->smc_type_v1))
1146 		return 0;
1147 	if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
1148 		return SMC_CLC_DECL_CNFERR;
1149 	return 0;
1150 }
1151 
1152 #define SMC_CLC_MAX_ACCEPT_LEN \
1153 	(sizeof(struct smc_clc_msg_accept_confirm) + \
1154 	 sizeof(struct smc_clc_first_contact_ext_v2x) + \
1155 	 sizeof(struct smc_clc_msg_trail))
1156 
1157 /* CLC handshake during connect */
1158 static int smc_connect_clc(struct smc_sock *smc,
1159 			   struct smc_clc_msg_accept_confirm *aclc,
1160 			   struct smc_init_info *ini)
1161 {
1162 	int rc = 0;
1163 
1164 	/* do inband token exchange */
1165 	rc = smc_clc_send_proposal(smc, ini);
1166 	if (rc)
1167 		return rc;
1168 	/* receive SMC Accept CLC message */
1169 	return smc_clc_wait_msg(smc, aclc, SMC_CLC_MAX_ACCEPT_LEN,
1170 				SMC_CLC_ACCEPT, CLC_WAIT_TIME);
1171 }
1172 
1173 void smc_fill_gid_list(struct smc_link_group *lgr,
1174 		       struct smc_gidlist *gidlist,
1175 		       struct smc_ib_device *known_dev, u8 *known_gid)
1176 {
1177 	struct smc_init_info *alt_ini = NULL;
1178 
1179 	memset(gidlist, 0, sizeof(*gidlist));
1180 	memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
1181 
1182 	alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
1183 	if (!alt_ini)
1184 		goto out;
1185 
1186 	alt_ini->vlan_id = lgr->vlan_id;
1187 	alt_ini->check_smcrv2 = true;
1188 	alt_ini->smcrv2.saddr = lgr->saddr;
1189 	smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
1190 
1191 	if (!alt_ini->smcrv2.ib_dev_v2)
1192 		goto out;
1193 
1194 	memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
1195 	       SMC_GID_SIZE);
1196 
1197 out:
1198 	kfree(alt_ini);
1199 }
1200 
1201 static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
1202 				       struct smc_clc_msg_accept_confirm *aclc,
1203 				       struct smc_init_info *ini)
1204 {
1205 	struct smc_clc_first_contact_ext *fce =
1206 		smc_get_clc_first_contact_ext(aclc, false);
1207 	struct net *net = sock_net(&smc->sk);
1208 	int rc;
1209 
1210 	if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1211 		return 0;
1212 
1213 	if (fce->v2_direct) {
1214 		memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1215 		ini->smcrv2.uses_gateway = false;
1216 	} else {
1217 		if (smc_ib_find_route(net, smc->clcsock->sk->sk_rcv_saddr,
1218 				      smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1219 				      ini->smcrv2.nexthop_mac,
1220 				      &ini->smcrv2.uses_gateway))
1221 			return SMC_CLC_DECL_NOROUTE;
1222 		if (!ini->smcrv2.uses_gateway) {
1223 			/* mismatch: peer claims indirect, but its direct */
1224 			return SMC_CLC_DECL_NOINDIRECT;
1225 		}
1226 	}
1227 
1228 	ini->release_nr = fce->release;
1229 	rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1230 	if (rc)
1231 		return rc;
1232 
1233 	return 0;
1234 }
1235 
1236 /* setup for RDMA connection of client */
1237 static int smc_connect_rdma(struct smc_sock *smc,
1238 			    struct smc_clc_msg_accept_confirm *aclc,
1239 			    struct smc_init_info *ini)
1240 {
1241 	int i, reason_code = 0;
1242 	struct smc_link *link;
1243 	u8 *eid = NULL;
1244 
1245 	ini->is_smcd = false;
1246 	ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1247 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1248 	memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1249 	memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1250 	memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1251 	ini->max_conns = SMC_CONN_PER_LGR_MAX;
1252 	ini->max_links = SMC_LINKS_ADD_LNK_MAX;
1253 
1254 	reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1255 	if (reason_code)
1256 		return reason_code;
1257 
1258 	mutex_lock(&smc_client_lgr_pending);
1259 	reason_code = smc_conn_create(smc, ini);
1260 	if (reason_code) {
1261 		mutex_unlock(&smc_client_lgr_pending);
1262 		return reason_code;
1263 	}
1264 
1265 	smc_conn_save_peer_info(smc, aclc);
1266 
1267 	if (ini->first_contact_local) {
1268 		link = smc->conn.lnk;
1269 	} else {
1270 		/* set link that was assigned by server */
1271 		link = NULL;
1272 		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1273 			struct smc_link *l = &smc->conn.lgr->lnk[i];
1274 
1275 			if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1276 			    !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1277 				    SMC_GID_SIZE) &&
1278 			    (aclc->hdr.version > SMC_V1 ||
1279 			     !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1280 				     sizeof(l->peer_mac)))) {
1281 				link = l;
1282 				break;
1283 			}
1284 		}
1285 		if (!link) {
1286 			reason_code = SMC_CLC_DECL_NOSRVLINK;
1287 			goto connect_abort;
1288 		}
1289 		smc_switch_link_and_count(&smc->conn, link);
1290 	}
1291 
1292 	/* create send buffer and rmb */
1293 	if (smc_buf_create(smc, false)) {
1294 		reason_code = SMC_CLC_DECL_MEM;
1295 		goto connect_abort;
1296 	}
1297 
1298 	if (ini->first_contact_local)
1299 		smc_link_save_peer_info(link, aclc, ini);
1300 
1301 	if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1302 		reason_code = SMC_CLC_DECL_ERR_RTOK;
1303 		goto connect_abort;
1304 	}
1305 
1306 	smc_rx_init(smc);
1307 
1308 	if (ini->first_contact_local) {
1309 		if (smc_ib_ready_link(link)) {
1310 			reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1311 			goto connect_abort;
1312 		}
1313 	} else {
1314 		/* reg sendbufs if they were vzalloced */
1315 		if (smc->conn.sndbuf_desc->is_vm) {
1316 			if (smcr_lgr_reg_sndbufs(link, smc->conn.sndbuf_desc)) {
1317 				reason_code = SMC_CLC_DECL_ERR_REGBUF;
1318 				goto connect_abort;
1319 			}
1320 		}
1321 		if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1322 			reason_code = SMC_CLC_DECL_ERR_REGBUF;
1323 			goto connect_abort;
1324 		}
1325 	}
1326 
1327 	if (aclc->hdr.version > SMC_V1) {
1328 		eid = aclc->r1.eid;
1329 		if (ini->first_contact_local)
1330 			smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1331 					  link->smcibdev, link->gid);
1332 	}
1333 
1334 	reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1335 					   aclc->hdr.version, eid, ini);
1336 	if (reason_code)
1337 		goto connect_abort;
1338 
1339 	smc_tx_init(smc);
1340 
1341 	if (ini->first_contact_local) {
1342 		/* QP confirmation over RoCE fabric */
1343 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1344 		reason_code = smcr_clnt_conf_first_link(smc);
1345 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1346 		if (reason_code)
1347 			goto connect_abort;
1348 	}
1349 	mutex_unlock(&smc_client_lgr_pending);
1350 
1351 	smc_copy_sock_settings_to_clc(smc);
1352 	smc->connect_nonblock = 0;
1353 	if (smc->sk.sk_state == SMC_INIT)
1354 		smc->sk.sk_state = SMC_ACTIVE;
1355 
1356 	return 0;
1357 connect_abort:
1358 	smc_conn_abort(smc, ini->first_contact_local);
1359 	mutex_unlock(&smc_client_lgr_pending);
1360 	smc->connect_nonblock = 0;
1361 
1362 	return reason_code;
1363 }
1364 
1365 /* The server has chosen one of the proposed ISM devices for the communication.
1366  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1367  */
1368 static int
1369 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm *aclc,
1370 			       struct smc_init_info *ini)
1371 {
1372 	int i;
1373 
1374 	for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1375 		if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1376 			ini->ism_selected = i;
1377 			return 0;
1378 		}
1379 	}
1380 
1381 	return -EPROTO;
1382 }
1383 
1384 /* setup for ISM connection of client */
1385 static int smc_connect_ism(struct smc_sock *smc,
1386 			   struct smc_clc_msg_accept_confirm *aclc,
1387 			   struct smc_init_info *ini)
1388 {
1389 	u8 *eid = NULL;
1390 	int rc = 0;
1391 
1392 	ini->is_smcd = true;
1393 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1394 
1395 	if (aclc->hdr.version == SMC_V2) {
1396 		if (ini->first_contact_peer) {
1397 			struct smc_clc_first_contact_ext *fce =
1398 				smc_get_clc_first_contact_ext(aclc, true);
1399 
1400 			ini->release_nr = fce->release;
1401 			rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1402 			if (rc)
1403 				return rc;
1404 		}
1405 
1406 		rc = smc_v2_determine_accepted_chid(aclc, ini);
1407 		if (rc)
1408 			return rc;
1409 
1410 		if (__smc_ism_is_emulated(ini->ism_chid[ini->ism_selected]))
1411 			ini->ism_peer_gid[ini->ism_selected].gid_ext =
1412 						ntohll(aclc->d1.gid_ext);
1413 		/* for non-Emulated-ISM devices, peer gid_ext remains 0. */
1414 	}
1415 	ini->ism_peer_gid[ini->ism_selected].gid = ntohll(aclc->d0.gid);
1416 
1417 	/* there is only one lgr role for SMC-D; use server lock */
1418 	mutex_lock(&smc_server_lgr_pending);
1419 	rc = smc_conn_create(smc, ini);
1420 	if (rc) {
1421 		mutex_unlock(&smc_server_lgr_pending);
1422 		return rc;
1423 	}
1424 
1425 	/* Create send and receive buffers */
1426 	rc = smc_buf_create(smc, true);
1427 	if (rc) {
1428 		rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1429 		goto connect_abort;
1430 	}
1431 
1432 	smc_conn_save_peer_info(smc, aclc);
1433 
1434 	if (smc_ism_support_dmb_nocopy(smc->conn.lgr->smcd)) {
1435 		rc = smcd_buf_attach(smc);
1436 		if (rc) {
1437 			rc = SMC_CLC_DECL_MEM;	/* try to fallback */
1438 			goto connect_abort;
1439 		}
1440 	}
1441 	smc_rx_init(smc);
1442 	smc_tx_init(smc);
1443 
1444 	if (aclc->hdr.version > SMC_V1)
1445 		eid = aclc->d1.eid;
1446 
1447 	rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1448 				  aclc->hdr.version, eid, ini);
1449 	if (rc)
1450 		goto connect_abort;
1451 	mutex_unlock(&smc_server_lgr_pending);
1452 
1453 	smc_copy_sock_settings_to_clc(smc);
1454 	smc->connect_nonblock = 0;
1455 	if (smc->sk.sk_state == SMC_INIT)
1456 		smc->sk.sk_state = SMC_ACTIVE;
1457 
1458 	return 0;
1459 connect_abort:
1460 	smc_conn_abort(smc, ini->first_contact_local);
1461 	mutex_unlock(&smc_server_lgr_pending);
1462 	smc->connect_nonblock = 0;
1463 
1464 	return rc;
1465 }
1466 
1467 /* check if received accept type and version matches a proposed one */
1468 static int smc_connect_check_aclc(struct smc_init_info *ini,
1469 				  struct smc_clc_msg_accept_confirm *aclc)
1470 {
1471 	if (aclc->hdr.version >= SMC_V2) {
1472 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1473 		     !smcr_indicated(ini->smc_type_v2)) ||
1474 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1475 		     !smcd_indicated(ini->smc_type_v2)))
1476 			return SMC_CLC_DECL_MODEUNSUPP;
1477 	} else {
1478 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1479 		     !smcr_indicated(ini->smc_type_v1)) ||
1480 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1481 		     !smcd_indicated(ini->smc_type_v1)))
1482 			return SMC_CLC_DECL_MODEUNSUPP;
1483 	}
1484 
1485 	return 0;
1486 }
1487 
1488 /* perform steps before actually connecting */
1489 static int __smc_connect(struct smc_sock *smc)
1490 {
1491 	u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1492 	struct smc_clc_msg_accept_confirm *aclc;
1493 	struct smc_init_info *ini = NULL;
1494 	u8 *buf = NULL;
1495 	int rc = 0;
1496 
1497 	if (smc->use_fallback)
1498 		return smc_connect_fallback(smc, smc->fallback_rsn);
1499 
1500 	/* if peer has not signalled SMC-capability, fall back */
1501 	if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1502 		return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1503 
1504 	/* IPSec connections opt out of SMC optimizations */
1505 	if (using_ipsec(smc))
1506 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1507 						    version);
1508 
1509 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1510 	if (!ini)
1511 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1512 						    version);
1513 
1514 	ini->smcd_version = SMC_V1 | SMC_V2;
1515 	ini->smcr_version = SMC_V1 | SMC_V2;
1516 	ini->smc_type_v1 = SMC_TYPE_B;
1517 	ini->smc_type_v2 = SMC_TYPE_B;
1518 
1519 	/* get vlan id from IP device */
1520 	if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1521 		ini->smcd_version &= ~SMC_V1;
1522 		ini->smcr_version = 0;
1523 		ini->smc_type_v1 = SMC_TYPE_N;
1524 	}
1525 
1526 	rc = smc_find_proposal_devices(smc, ini);
1527 	if (rc)
1528 		goto fallback;
1529 
1530 	buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1531 	if (!buf) {
1532 		rc = SMC_CLC_DECL_MEM;
1533 		goto fallback;
1534 	}
1535 	aclc = (struct smc_clc_msg_accept_confirm *)buf;
1536 
1537 	/* perform CLC handshake */
1538 	rc = smc_connect_clc(smc, aclc, ini);
1539 	if (rc) {
1540 		/* -EAGAIN on timeout, see tcp_recvmsg() */
1541 		if (rc == -EAGAIN) {
1542 			rc = -ETIMEDOUT;
1543 			smc->sk.sk_err = ETIMEDOUT;
1544 		}
1545 		goto vlan_cleanup;
1546 	}
1547 
1548 	/* check if smc modes and versions of CLC proposal and accept match */
1549 	rc = smc_connect_check_aclc(ini, aclc);
1550 	version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1551 	if (rc)
1552 		goto vlan_cleanup;
1553 
1554 	/* depending on previous steps, connect using rdma or ism */
1555 	if (aclc->hdr.typev1 == SMC_TYPE_R) {
1556 		ini->smcr_version = version;
1557 		rc = smc_connect_rdma(smc, aclc, ini);
1558 	} else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1559 		ini->smcd_version = version;
1560 		rc = smc_connect_ism(smc, aclc, ini);
1561 	}
1562 	if (rc)
1563 		goto vlan_cleanup;
1564 
1565 	SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1566 	smc_connect_ism_vlan_cleanup(smc, ini);
1567 	kfree(buf);
1568 	kfree(ini);
1569 	return 0;
1570 
1571 vlan_cleanup:
1572 	smc_connect_ism_vlan_cleanup(smc, ini);
1573 	kfree(buf);
1574 fallback:
1575 	kfree(ini);
1576 	return smc_connect_decline_fallback(smc, rc, version);
1577 }
1578 
1579 static void smc_connect_work(struct work_struct *work)
1580 {
1581 	struct smc_sock *smc = container_of(work, struct smc_sock,
1582 					    connect_work);
1583 	long timeo = smc->sk.sk_sndtimeo;
1584 	int rc = 0;
1585 
1586 	if (!timeo)
1587 		timeo = MAX_SCHEDULE_TIMEOUT;
1588 	lock_sock(smc->clcsock->sk);
1589 	if (smc->clcsock->sk->sk_err) {
1590 		smc->sk.sk_err = smc->clcsock->sk->sk_err;
1591 	} else if ((1 << smc->clcsock->sk->sk_state) &
1592 					(TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1593 		rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1594 		if ((rc == -EPIPE) &&
1595 		    ((1 << smc->clcsock->sk->sk_state) &
1596 					(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1597 			rc = 0;
1598 	}
1599 	release_sock(smc->clcsock->sk);
1600 	lock_sock(&smc->sk);
1601 	if (rc != 0 || smc->sk.sk_err) {
1602 		smc->sk.sk_state = SMC_CLOSED;
1603 		if (rc == -EPIPE || rc == -EAGAIN)
1604 			smc->sk.sk_err = EPIPE;
1605 		else if (rc == -ECONNREFUSED)
1606 			smc->sk.sk_err = ECONNREFUSED;
1607 		else if (signal_pending(current))
1608 			smc->sk.sk_err = -sock_intr_errno(timeo);
1609 		sock_put(&smc->sk); /* passive closing */
1610 		goto out;
1611 	}
1612 
1613 	rc = __smc_connect(smc);
1614 	if (rc < 0)
1615 		smc->sk.sk_err = -rc;
1616 
1617 out:
1618 	if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1619 		if (smc->sk.sk_err) {
1620 			smc->sk.sk_state_change(&smc->sk);
1621 		} else { /* allow polling before and after fallback decision */
1622 			smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1623 			smc->sk.sk_write_space(&smc->sk);
1624 		}
1625 	}
1626 	release_sock(&smc->sk);
1627 }
1628 
1629 int smc_connect(struct socket *sock, struct sockaddr *addr,
1630 		int alen, int flags)
1631 {
1632 	struct sock *sk = sock->sk;
1633 	struct smc_sock *smc;
1634 	int rc = -EINVAL;
1635 
1636 	smc = smc_sk(sk);
1637 
1638 	/* separate smc parameter checking to be safe */
1639 	if (alen < sizeof(addr->sa_family))
1640 		goto out_err;
1641 	if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1642 		goto out_err;
1643 
1644 	lock_sock(sk);
1645 	switch (sock->state) {
1646 	default:
1647 		rc = -EINVAL;
1648 		goto out;
1649 	case SS_CONNECTED:
1650 		rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1651 		goto out;
1652 	case SS_CONNECTING:
1653 		if (sk->sk_state == SMC_ACTIVE)
1654 			goto connected;
1655 		break;
1656 	case SS_UNCONNECTED:
1657 		sock->state = SS_CONNECTING;
1658 		break;
1659 	}
1660 
1661 	switch (sk->sk_state) {
1662 	default:
1663 		goto out;
1664 	case SMC_CLOSED:
1665 		rc = sock_error(sk) ? : -ECONNABORTED;
1666 		sock->state = SS_UNCONNECTED;
1667 		goto out;
1668 	case SMC_ACTIVE:
1669 		rc = -EISCONN;
1670 		goto out;
1671 	case SMC_INIT:
1672 		break;
1673 	}
1674 
1675 	smc_copy_sock_settings_to_clc(smc);
1676 	tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1677 	if (smc->connect_nonblock) {
1678 		rc = -EALREADY;
1679 		goto out;
1680 	}
1681 	rc = kernel_connect(smc->clcsock, addr, alen, flags);
1682 	if (rc && rc != -EINPROGRESS)
1683 		goto out;
1684 
1685 	if (smc->use_fallback) {
1686 		sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1687 		goto out;
1688 	}
1689 	sock_hold(&smc->sk); /* sock put in passive closing */
1690 	if (flags & O_NONBLOCK) {
1691 		if (queue_work(smc_hs_wq, &smc->connect_work))
1692 			smc->connect_nonblock = 1;
1693 		rc = -EINPROGRESS;
1694 		goto out;
1695 	} else {
1696 		rc = __smc_connect(smc);
1697 		if (rc < 0)
1698 			goto out;
1699 	}
1700 
1701 connected:
1702 	rc = 0;
1703 	sock->state = SS_CONNECTED;
1704 out:
1705 	release_sock(sk);
1706 out_err:
1707 	return rc;
1708 }
1709 
1710 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1711 {
1712 	struct socket *new_clcsock = NULL;
1713 	struct sock *lsk = &lsmc->sk;
1714 	struct sock *new_sk;
1715 	int rc = -EINVAL;
1716 
1717 	release_sock(lsk);
1718 	new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1719 	if (!new_sk) {
1720 		rc = -ENOMEM;
1721 		lsk->sk_err = ENOMEM;
1722 		*new_smc = NULL;
1723 		lock_sock(lsk);
1724 		goto out;
1725 	}
1726 	*new_smc = smc_sk(new_sk);
1727 
1728 	mutex_lock(&lsmc->clcsock_release_lock);
1729 	if (lsmc->clcsock)
1730 		rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1731 	mutex_unlock(&lsmc->clcsock_release_lock);
1732 	lock_sock(lsk);
1733 	if  (rc < 0 && rc != -EAGAIN)
1734 		lsk->sk_err = -rc;
1735 	if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1736 		new_sk->sk_prot->unhash(new_sk);
1737 		if (new_clcsock)
1738 			sock_release(new_clcsock);
1739 		new_sk->sk_state = SMC_CLOSED;
1740 		smc_sock_set_flag(new_sk, SOCK_DEAD);
1741 		sock_put(new_sk); /* final */
1742 		*new_smc = NULL;
1743 		goto out;
1744 	}
1745 
1746 	/* new clcsock has inherited the smc listen-specific sk_data_ready
1747 	 * function; switch it back to the original sk_data_ready function
1748 	 */
1749 	new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1750 
1751 	/* if new clcsock has also inherited the fallback-specific callback
1752 	 * functions, switch them back to the original ones.
1753 	 */
1754 	if (lsmc->use_fallback) {
1755 		if (lsmc->clcsk_state_change)
1756 			new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1757 		if (lsmc->clcsk_write_space)
1758 			new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1759 		if (lsmc->clcsk_error_report)
1760 			new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1761 	}
1762 
1763 	(*new_smc)->clcsock = new_clcsock;
1764 out:
1765 	return rc;
1766 }
1767 
1768 /* add a just created sock to the accept queue of the listen sock as
1769  * candidate for a following socket accept call from user space
1770  */
1771 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1772 {
1773 	struct smc_sock *par = smc_sk(parent);
1774 
1775 	sock_hold(sk); /* sock_put in smc_accept_unlink () */
1776 	spin_lock(&par->accept_q_lock);
1777 	list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1778 	spin_unlock(&par->accept_q_lock);
1779 	sk_acceptq_added(parent);
1780 }
1781 
1782 /* remove a socket from the accept queue of its parental listening socket */
1783 static void smc_accept_unlink(struct sock *sk)
1784 {
1785 	struct smc_sock *par = smc_sk(sk)->listen_smc;
1786 
1787 	spin_lock(&par->accept_q_lock);
1788 	list_del_init(&smc_sk(sk)->accept_q);
1789 	spin_unlock(&par->accept_q_lock);
1790 	sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1791 	sock_put(sk); /* sock_hold in smc_accept_enqueue */
1792 }
1793 
1794 /* remove a sock from the accept queue to bind it to a new socket created
1795  * for a socket accept call from user space
1796  */
1797 struct sock *smc_accept_dequeue(struct sock *parent,
1798 				struct socket *new_sock)
1799 {
1800 	struct smc_sock *isk, *n;
1801 	struct sock *new_sk;
1802 
1803 	list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1804 		new_sk = (struct sock *)isk;
1805 
1806 		smc_accept_unlink(new_sk);
1807 		if (new_sk->sk_state == SMC_CLOSED) {
1808 			new_sk->sk_prot->unhash(new_sk);
1809 			if (isk->clcsock) {
1810 				sock_release(isk->clcsock);
1811 				isk->clcsock = NULL;
1812 			}
1813 			sock_put(new_sk); /* final */
1814 			continue;
1815 		}
1816 		if (new_sock) {
1817 			sock_graft(new_sk, new_sock);
1818 			new_sock->state = SS_CONNECTED;
1819 			if (isk->use_fallback) {
1820 				smc_sk(new_sk)->clcsock->file = new_sock->file;
1821 				isk->clcsock->file->private_data = isk->clcsock;
1822 			}
1823 		}
1824 		return new_sk;
1825 	}
1826 	return NULL;
1827 }
1828 
1829 /* clean up for a created but never accepted sock */
1830 void smc_close_non_accepted(struct sock *sk)
1831 {
1832 	struct smc_sock *smc = smc_sk(sk);
1833 
1834 	sock_hold(sk); /* sock_put below */
1835 	lock_sock(sk);
1836 	if (!sk->sk_lingertime)
1837 		/* wait for peer closing */
1838 		WRITE_ONCE(sk->sk_lingertime, SMC_MAX_STREAM_WAIT_TIMEOUT);
1839 	__smc_release(smc);
1840 	release_sock(sk);
1841 	sock_put(sk); /* sock_hold above */
1842 	sock_put(sk); /* final sock_put */
1843 }
1844 
1845 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1846 {
1847 	struct smc_link *link = smc->conn.lnk;
1848 	struct smc_llc_qentry *qentry;
1849 	int rc;
1850 
1851 	/* reg the sndbuf if it was vzalloced*/
1852 	if (smc->conn.sndbuf_desc->is_vm) {
1853 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
1854 			return SMC_CLC_DECL_ERR_REGBUF;
1855 	}
1856 
1857 	/* reg the rmb */
1858 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
1859 		return SMC_CLC_DECL_ERR_REGBUF;
1860 
1861 	/* send CONFIRM LINK request to client over the RoCE fabric */
1862 	rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1863 	if (rc < 0)
1864 		return SMC_CLC_DECL_TIMEOUT_CL;
1865 
1866 	/* receive CONFIRM LINK response from client over the RoCE fabric */
1867 	qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1868 			      SMC_LLC_CONFIRM_LINK);
1869 	if (!qentry) {
1870 		struct smc_clc_msg_decline dclc;
1871 
1872 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1873 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1874 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1875 	}
1876 	smc_llc_save_peer_uid(qentry);
1877 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1878 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1879 	if (rc)
1880 		return SMC_CLC_DECL_RMBE_EC;
1881 
1882 	/* confirm_rkey is implicit on 1st contact */
1883 	smc->conn.rmb_desc->is_conf_rkey = true;
1884 
1885 	smc_llc_link_active(link);
1886 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1887 
1888 	if (link->lgr->max_links > 1) {
1889 		down_write(&link->lgr->llc_conf_mutex);
1890 		/* initial contact - try to establish second link */
1891 		smc_llc_srv_add_link(link, NULL);
1892 		up_write(&link->lgr->llc_conf_mutex);
1893 	}
1894 	return 0;
1895 }
1896 
1897 /* listen worker: finish */
1898 static void smc_listen_out(struct smc_sock *new_smc)
1899 {
1900 	struct smc_sock *lsmc = new_smc->listen_smc;
1901 	struct sock *newsmcsk = &new_smc->sk;
1902 
1903 	if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1904 		atomic_dec(&lsmc->queued_smc_hs);
1905 
1906 	release_sock(newsmcsk); /* lock in smc_listen_work() */
1907 	if (lsmc->sk.sk_state == SMC_LISTEN) {
1908 		lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1909 		smc_accept_enqueue(&lsmc->sk, newsmcsk);
1910 		release_sock(&lsmc->sk);
1911 	} else { /* no longer listening */
1912 		smc_close_non_accepted(newsmcsk);
1913 	}
1914 
1915 	/* Wake up accept */
1916 	lsmc->sk.sk_data_ready(&lsmc->sk);
1917 	sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1918 }
1919 
1920 /* listen worker: finish in state connected */
1921 static void smc_listen_out_connected(struct smc_sock *new_smc)
1922 {
1923 	struct sock *newsmcsk = &new_smc->sk;
1924 
1925 	if (newsmcsk->sk_state == SMC_INIT)
1926 		newsmcsk->sk_state = SMC_ACTIVE;
1927 
1928 	smc_listen_out(new_smc);
1929 }
1930 
1931 /* listen worker: finish in error state */
1932 static void smc_listen_out_err(struct smc_sock *new_smc)
1933 {
1934 	struct sock *newsmcsk = &new_smc->sk;
1935 	struct net *net = sock_net(newsmcsk);
1936 
1937 	this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1938 	if (newsmcsk->sk_state == SMC_INIT)
1939 		sock_put(&new_smc->sk); /* passive closing */
1940 	newsmcsk->sk_state = SMC_CLOSED;
1941 
1942 	smc_listen_out(new_smc);
1943 }
1944 
1945 /* listen worker: decline and fall back if possible */
1946 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1947 			       int local_first, u8 version)
1948 {
1949 	/* RDMA setup failed, switch back to TCP */
1950 	smc_conn_abort(new_smc, local_first);
1951 	if (reason_code < 0 ||
1952 	    smc_switch_to_fallback(new_smc, reason_code)) {
1953 		/* error, no fallback possible */
1954 		smc_listen_out_err(new_smc);
1955 		return;
1956 	}
1957 	if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1958 		if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1959 			smc_listen_out_err(new_smc);
1960 			return;
1961 		}
1962 	}
1963 	smc_listen_out_connected(new_smc);
1964 }
1965 
1966 /* listen worker: version checking */
1967 static int smc_listen_v2_check(struct smc_sock *new_smc,
1968 			       struct smc_clc_msg_proposal *pclc,
1969 			       struct smc_init_info *ini)
1970 {
1971 	struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1972 	struct smc_clc_v2_extension *pclc_v2_ext;
1973 	int rc = SMC_CLC_DECL_PEERNOSMC;
1974 
1975 	ini->smc_type_v1 = pclc->hdr.typev1;
1976 	ini->smc_type_v2 = pclc->hdr.typev2;
1977 	ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1978 	ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1979 	if (pclc->hdr.version > SMC_V1) {
1980 		if (smcd_indicated(ini->smc_type_v2))
1981 			ini->smcd_version |= SMC_V2;
1982 		if (smcr_indicated(ini->smc_type_v2))
1983 			ini->smcr_version |= SMC_V2;
1984 	}
1985 	if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1986 		rc = SMC_CLC_DECL_PEERNOSMC;
1987 		goto out;
1988 	}
1989 	pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1990 	if (!pclc_v2_ext) {
1991 		ini->smcd_version &= ~SMC_V2;
1992 		ini->smcr_version &= ~SMC_V2;
1993 		rc = SMC_CLC_DECL_NOV2EXT;
1994 		goto out;
1995 	}
1996 	pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
1997 	if (ini->smcd_version & SMC_V2) {
1998 		if (!smc_ism_is_v2_capable()) {
1999 			ini->smcd_version &= ~SMC_V2;
2000 			rc = SMC_CLC_DECL_NOISM2SUPP;
2001 		} else if (!pclc_smcd_v2_ext) {
2002 			ini->smcd_version &= ~SMC_V2;
2003 			rc = SMC_CLC_DECL_NOV2DEXT;
2004 		} else if (!pclc_v2_ext->hdr.eid_cnt &&
2005 			   !pclc_v2_ext->hdr.flag.seid) {
2006 			ini->smcd_version &= ~SMC_V2;
2007 			rc = SMC_CLC_DECL_NOUEID;
2008 		}
2009 	}
2010 	if (ini->smcr_version & SMC_V2) {
2011 		if (!pclc_v2_ext->hdr.eid_cnt) {
2012 			ini->smcr_version &= ~SMC_V2;
2013 			rc = SMC_CLC_DECL_NOUEID;
2014 		}
2015 	}
2016 
2017 	ini->release_nr = pclc_v2_ext->hdr.flag.release;
2018 	if (pclc_v2_ext->hdr.flag.release > SMC_RELEASE)
2019 		ini->release_nr = SMC_RELEASE;
2020 
2021 out:
2022 	if (!ini->smcd_version && !ini->smcr_version)
2023 		return rc;
2024 
2025 	return 0;
2026 }
2027 
2028 /* listen worker: check prefixes */
2029 static int smc_listen_prfx_check(struct smc_sock *new_smc,
2030 				 struct smc_clc_msg_proposal *pclc)
2031 {
2032 	struct smc_clc_msg_proposal_prefix *pclc_prfx;
2033 	struct socket *newclcsock = new_smc->clcsock;
2034 
2035 	if (pclc->hdr.typev1 == SMC_TYPE_N)
2036 		return 0;
2037 	pclc_prfx = smc_clc_proposal_get_prefix(pclc);
2038 	if (smc_clc_prfx_match(newclcsock, pclc_prfx))
2039 		return SMC_CLC_DECL_DIFFPREFIX;
2040 
2041 	return 0;
2042 }
2043 
2044 /* listen worker: initialize connection and buffers */
2045 static int smc_listen_rdma_init(struct smc_sock *new_smc,
2046 				struct smc_init_info *ini)
2047 {
2048 	int rc;
2049 
2050 	/* allocate connection / link group */
2051 	rc = smc_conn_create(new_smc, ini);
2052 	if (rc)
2053 		return rc;
2054 
2055 	/* create send buffer and rmb */
2056 	if (smc_buf_create(new_smc, false)) {
2057 		smc_conn_abort(new_smc, ini->first_contact_local);
2058 		return SMC_CLC_DECL_MEM;
2059 	}
2060 
2061 	return 0;
2062 }
2063 
2064 /* listen worker: initialize connection and buffers for SMC-D */
2065 static int smc_listen_ism_init(struct smc_sock *new_smc,
2066 			       struct smc_init_info *ini)
2067 {
2068 	int rc;
2069 
2070 	rc = smc_conn_create(new_smc, ini);
2071 	if (rc)
2072 		return rc;
2073 
2074 	/* Create send and receive buffers */
2075 	rc = smc_buf_create(new_smc, true);
2076 	if (rc) {
2077 		smc_conn_abort(new_smc, ini->first_contact_local);
2078 		return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2079 					 SMC_CLC_DECL_MEM;
2080 	}
2081 
2082 	return 0;
2083 }
2084 
2085 static bool smc_is_already_selected(struct smcd_dev *smcd,
2086 				    struct smc_init_info *ini,
2087 				    int matches)
2088 {
2089 	int i;
2090 
2091 	for (i = 0; i < matches; i++)
2092 		if (smcd == ini->ism_dev[i])
2093 			return true;
2094 
2095 	return false;
2096 }
2097 
2098 /* check for ISM devices matching proposed ISM devices */
2099 static void smc_check_ism_v2_match(struct smc_init_info *ini,
2100 				   u16 proposed_chid,
2101 				   struct smcd_gid *proposed_gid,
2102 				   unsigned int *matches)
2103 {
2104 	struct smcd_dev *smcd;
2105 
2106 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2107 		if (smcd->going_away)
2108 			continue;
2109 		if (smc_is_already_selected(smcd, ini, *matches))
2110 			continue;
2111 		if (smc_ism_get_chid(smcd) == proposed_chid &&
2112 		    !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2113 			ini->ism_peer_gid[*matches].gid = proposed_gid->gid;
2114 			if (__smc_ism_is_emulated(proposed_chid))
2115 				ini->ism_peer_gid[*matches].gid_ext =
2116 							proposed_gid->gid_ext;
2117 				/* non-Emulated-ISM's peer gid_ext remains 0. */
2118 			ini->ism_dev[*matches] = smcd;
2119 			(*matches)++;
2120 			break;
2121 		}
2122 	}
2123 }
2124 
2125 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2126 {
2127 	if (!ini->rc)
2128 		ini->rc = rc;
2129 }
2130 
2131 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2132 					struct smc_clc_msg_proposal *pclc,
2133 					struct smc_init_info *ini)
2134 {
2135 	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2136 	struct smc_clc_v2_extension *smc_v2_ext;
2137 	struct smc_clc_msg_smcd *pclc_smcd;
2138 	unsigned int matches = 0;
2139 	struct smcd_gid smcd_gid;
2140 	u8 smcd_version;
2141 	u8 *eid = NULL;
2142 	int i, rc;
2143 	u16 chid;
2144 
2145 	if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2146 		goto not_found;
2147 
2148 	pclc_smcd = smc_get_clc_msg_smcd(pclc);
2149 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2150 	smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2151 
2152 	mutex_lock(&smcd_dev_list.mutex);
2153 	if (pclc_smcd->ism.chid) {
2154 		/* check for ISM device matching proposed native ISM device */
2155 		smcd_gid.gid = ntohll(pclc_smcd->ism.gid);
2156 		smcd_gid.gid_ext = 0;
2157 		smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2158 				       &smcd_gid, &matches);
2159 	}
2160 	for (i = 0; i < smc_v2_ext->hdr.ism_gid_cnt; i++) {
2161 		/* check for ISM devices matching proposed non-native ISM
2162 		 * devices
2163 		 */
2164 		smcd_gid.gid = ntohll(smcd_v2_ext->gidchid[i].gid);
2165 		smcd_gid.gid_ext = 0;
2166 		chid = ntohs(smcd_v2_ext->gidchid[i].chid);
2167 		if (__smc_ism_is_emulated(chid)) {
2168 			if ((i + 1) == smc_v2_ext->hdr.ism_gid_cnt ||
2169 			    chid != ntohs(smcd_v2_ext->gidchid[i + 1].chid))
2170 				/* each Emulated-ISM device takes two GID-CHID
2171 				 * entries and CHID of the second entry repeats
2172 				 * that of the first entry.
2173 				 *
2174 				 * So check if the next GID-CHID entry exists
2175 				 * and both two entries' CHIDs are the same.
2176 				 */
2177 				continue;
2178 			smcd_gid.gid_ext =
2179 				ntohll(smcd_v2_ext->gidchid[++i].gid);
2180 		}
2181 		smc_check_ism_v2_match(ini, chid, &smcd_gid, &matches);
2182 	}
2183 	mutex_unlock(&smcd_dev_list.mutex);
2184 
2185 	if (!ini->ism_dev[0]) {
2186 		smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2187 		goto not_found;
2188 	}
2189 
2190 	smc_ism_get_system_eid(&eid);
2191 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2192 			       smcd_v2_ext->system_eid, eid))
2193 		goto not_found;
2194 
2195 	/* separate - outside the smcd_dev_list.lock */
2196 	smcd_version = ini->smcd_version;
2197 	for (i = 0; i < matches; i++) {
2198 		ini->smcd_version = SMC_V2;
2199 		ini->is_smcd = true;
2200 		ini->ism_selected = i;
2201 		rc = smc_listen_ism_init(new_smc, ini);
2202 		if (rc) {
2203 			smc_find_ism_store_rc(rc, ini);
2204 			/* try next active ISM device */
2205 			continue;
2206 		}
2207 		return; /* matching and usable V2 ISM device found */
2208 	}
2209 	/* no V2 ISM device could be initialized */
2210 	ini->smcd_version = smcd_version;	/* restore original value */
2211 	ini->negotiated_eid[0] = 0;
2212 
2213 not_found:
2214 	ini->smcd_version &= ~SMC_V2;
2215 	ini->ism_dev[0] = NULL;
2216 	ini->is_smcd = false;
2217 }
2218 
2219 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2220 					struct smc_clc_msg_proposal *pclc,
2221 					struct smc_init_info *ini)
2222 {
2223 	struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2224 	int rc = 0;
2225 
2226 	/* check if ISM V1 is available */
2227 	if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2228 		goto not_found;
2229 	ini->is_smcd = true; /* prepare ISM check */
2230 	ini->ism_peer_gid[0].gid = ntohll(pclc_smcd->ism.gid);
2231 	ini->ism_peer_gid[0].gid_ext = 0;
2232 	rc = smc_find_ism_device(new_smc, ini);
2233 	if (rc)
2234 		goto not_found;
2235 	ini->ism_selected = 0;
2236 	rc = smc_listen_ism_init(new_smc, ini);
2237 	if (!rc)
2238 		return;		/* V1 ISM device found */
2239 
2240 not_found:
2241 	smc_find_ism_store_rc(rc, ini);
2242 	ini->smcd_version &= ~SMC_V1;
2243 	ini->ism_dev[0] = NULL;
2244 	ini->is_smcd = false;
2245 }
2246 
2247 /* listen worker: register buffers */
2248 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2249 {
2250 	struct smc_connection *conn = &new_smc->conn;
2251 
2252 	if (!local_first) {
2253 		/* reg sendbufs if they were vzalloced */
2254 		if (conn->sndbuf_desc->is_vm) {
2255 			if (smcr_lgr_reg_sndbufs(conn->lnk,
2256 						 conn->sndbuf_desc))
2257 				return SMC_CLC_DECL_ERR_REGBUF;
2258 		}
2259 		if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2260 			return SMC_CLC_DECL_ERR_REGBUF;
2261 	}
2262 
2263 	return 0;
2264 }
2265 
2266 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2267 					 struct smc_clc_msg_proposal *pclc,
2268 					 struct smc_init_info *ini)
2269 {
2270 	struct smc_clc_v2_extension *smc_v2_ext;
2271 	u8 smcr_version;
2272 	int rc;
2273 
2274 	if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2275 		goto not_found;
2276 
2277 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2278 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2279 		goto not_found;
2280 
2281 	/* prepare RDMA check */
2282 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2283 	memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2284 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2285 	ini->check_smcrv2 = true;
2286 	ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2287 	ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2288 	ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2289 	rc = smc_find_rdma_device(new_smc, ini);
2290 	if (rc) {
2291 		smc_find_ism_store_rc(rc, ini);
2292 		goto not_found;
2293 	}
2294 	if (!ini->smcrv2.uses_gateway)
2295 		memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2296 
2297 	smcr_version = ini->smcr_version;
2298 	ini->smcr_version = SMC_V2;
2299 	rc = smc_listen_rdma_init(new_smc, ini);
2300 	if (!rc) {
2301 		rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2302 		if (rc)
2303 			smc_conn_abort(new_smc, ini->first_contact_local);
2304 	}
2305 	if (!rc)
2306 		return;
2307 	ini->smcr_version = smcr_version;
2308 	smc_find_ism_store_rc(rc, ini);
2309 
2310 not_found:
2311 	ini->smcr_version &= ~SMC_V2;
2312 	ini->smcrv2.ib_dev_v2 = NULL;
2313 	ini->check_smcrv2 = false;
2314 }
2315 
2316 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2317 					struct smc_clc_msg_proposal *pclc,
2318 					struct smc_init_info *ini)
2319 {
2320 	int rc;
2321 
2322 	if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2323 		return SMC_CLC_DECL_NOSMCDEV;
2324 
2325 	/* prepare RDMA check */
2326 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2327 	memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2328 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2329 	rc = smc_find_rdma_device(new_smc, ini);
2330 	if (rc) {
2331 		/* no RDMA device found */
2332 		return SMC_CLC_DECL_NOSMCDEV;
2333 	}
2334 	rc = smc_listen_rdma_init(new_smc, ini);
2335 	if (rc)
2336 		return rc;
2337 	return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2338 }
2339 
2340 /* determine the local device matching to proposal */
2341 static int smc_listen_find_device(struct smc_sock *new_smc,
2342 				  struct smc_clc_msg_proposal *pclc,
2343 				  struct smc_init_info *ini)
2344 {
2345 	int prfx_rc;
2346 
2347 	/* check for ISM device matching V2 proposed device */
2348 	smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2349 	if (ini->ism_dev[0])
2350 		return 0;
2351 
2352 	/* check for matching IP prefix and subnet length (V1) */
2353 	prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2354 	if (prfx_rc)
2355 		smc_find_ism_store_rc(prfx_rc, ini);
2356 
2357 	/* get vlan id from IP device */
2358 	if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2359 		return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2360 
2361 	/* check for ISM device matching V1 proposed device */
2362 	if (!prfx_rc)
2363 		smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2364 	if (ini->ism_dev[0])
2365 		return 0;
2366 
2367 	if (!smcr_indicated(pclc->hdr.typev1) &&
2368 	    !smcr_indicated(pclc->hdr.typev2))
2369 		/* skip RDMA and decline */
2370 		return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2371 
2372 	/* check if RDMA V2 is available */
2373 	smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2374 	if (ini->smcrv2.ib_dev_v2)
2375 		return 0;
2376 
2377 	/* check if RDMA V1 is available */
2378 	if (!prfx_rc) {
2379 		int rc;
2380 
2381 		rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2382 		smc_find_ism_store_rc(rc, ini);
2383 		return (!rc) ? 0 : ini->rc;
2384 	}
2385 	return prfx_rc;
2386 }
2387 
2388 /* listen worker: finish RDMA setup */
2389 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2390 				  struct smc_clc_msg_accept_confirm *cclc,
2391 				  bool local_first,
2392 				  struct smc_init_info *ini)
2393 {
2394 	struct smc_link *link = new_smc->conn.lnk;
2395 	int reason_code = 0;
2396 
2397 	if (local_first)
2398 		smc_link_save_peer_info(link, cclc, ini);
2399 
2400 	if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2401 		return SMC_CLC_DECL_ERR_RTOK;
2402 
2403 	if (local_first) {
2404 		if (smc_ib_ready_link(link))
2405 			return SMC_CLC_DECL_ERR_RDYLNK;
2406 		/* QP confirmation over RoCE fabric */
2407 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2408 		reason_code = smcr_serv_conf_first_link(new_smc);
2409 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2410 	}
2411 	return reason_code;
2412 }
2413 
2414 /* setup for connection of server */
2415 static void smc_listen_work(struct work_struct *work)
2416 {
2417 	struct smc_sock *new_smc = container_of(work, struct smc_sock,
2418 						smc_listen_work);
2419 	struct socket *newclcsock = new_smc->clcsock;
2420 	struct smc_clc_msg_accept_confirm *cclc;
2421 	struct smc_clc_msg_proposal_area *buf;
2422 	struct smc_clc_msg_proposal *pclc;
2423 	struct smc_init_info *ini = NULL;
2424 	u8 proposal_version = SMC_V1;
2425 	u8 accept_version;
2426 	int rc = 0;
2427 
2428 	lock_sock(&new_smc->sk); /* release in smc_listen_out() */
2429 	if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2430 		return smc_listen_out_err(new_smc);
2431 
2432 	if (new_smc->use_fallback) {
2433 		smc_listen_out_connected(new_smc);
2434 		return;
2435 	}
2436 
2437 	/* check if peer is smc capable */
2438 	if (!tcp_sk(newclcsock->sk)->syn_smc) {
2439 		rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2440 		if (rc)
2441 			smc_listen_out_err(new_smc);
2442 		else
2443 			smc_listen_out_connected(new_smc);
2444 		return;
2445 	}
2446 
2447 	/* do inband token exchange -
2448 	 * wait for and receive SMC Proposal CLC message
2449 	 */
2450 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2451 	if (!buf) {
2452 		rc = SMC_CLC_DECL_MEM;
2453 		goto out_decl;
2454 	}
2455 	pclc = (struct smc_clc_msg_proposal *)buf;
2456 	rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2457 			      SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2458 	if (rc)
2459 		goto out_decl;
2460 
2461 	if (pclc->hdr.version > SMC_V1)
2462 		proposal_version = SMC_V2;
2463 
2464 	/* IPSec connections opt out of SMC optimizations */
2465 	if (using_ipsec(new_smc)) {
2466 		rc = SMC_CLC_DECL_IPSEC;
2467 		goto out_decl;
2468 	}
2469 
2470 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2471 	if (!ini) {
2472 		rc = SMC_CLC_DECL_MEM;
2473 		goto out_decl;
2474 	}
2475 
2476 	/* initial version checking */
2477 	rc = smc_listen_v2_check(new_smc, pclc, ini);
2478 	if (rc)
2479 		goto out_decl;
2480 
2481 	rc = smc_clc_srv_v2x_features_validate(new_smc, pclc, ini);
2482 	if (rc)
2483 		goto out_decl;
2484 
2485 	mutex_lock(&smc_server_lgr_pending);
2486 	smc_rx_init(new_smc);
2487 	smc_tx_init(new_smc);
2488 
2489 	/* determine ISM or RoCE device used for connection */
2490 	rc = smc_listen_find_device(new_smc, pclc, ini);
2491 	if (rc)
2492 		goto out_unlock;
2493 
2494 	/* send SMC Accept CLC message */
2495 	accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2496 	rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2497 				 accept_version, ini->negotiated_eid, ini);
2498 	if (rc)
2499 		goto out_unlock;
2500 
2501 	/* SMC-D does not need this lock any more */
2502 	if (ini->is_smcd)
2503 		mutex_unlock(&smc_server_lgr_pending);
2504 
2505 	/* receive SMC Confirm CLC message */
2506 	memset(buf, 0, sizeof(*buf));
2507 	cclc = (struct smc_clc_msg_accept_confirm *)buf;
2508 	rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2509 			      SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2510 	if (rc) {
2511 		if (!ini->is_smcd)
2512 			goto out_unlock;
2513 		goto out_decl;
2514 	}
2515 
2516 	rc = smc_clc_v2x_features_confirm_check(cclc, ini);
2517 	if (rc) {
2518 		if (!ini->is_smcd)
2519 			goto out_unlock;
2520 		goto out_decl;
2521 	}
2522 
2523 	/* fce smc release version is needed in smc_listen_rdma_finish,
2524 	 * so save fce info here.
2525 	 */
2526 	smc_conn_save_peer_info_fce(new_smc, cclc);
2527 
2528 	/* finish worker */
2529 	if (!ini->is_smcd) {
2530 		rc = smc_listen_rdma_finish(new_smc, cclc,
2531 					    ini->first_contact_local, ini);
2532 		if (rc)
2533 			goto out_unlock;
2534 		mutex_unlock(&smc_server_lgr_pending);
2535 	}
2536 	smc_conn_save_peer_info(new_smc, cclc);
2537 
2538 	if (ini->is_smcd &&
2539 	    smc_ism_support_dmb_nocopy(new_smc->conn.lgr->smcd)) {
2540 		rc = smcd_buf_attach(new_smc);
2541 		if (rc)
2542 			goto out_decl;
2543 	}
2544 
2545 	smc_listen_out_connected(new_smc);
2546 	SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2547 	goto out_free;
2548 
2549 out_unlock:
2550 	mutex_unlock(&smc_server_lgr_pending);
2551 out_decl:
2552 	smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2553 			   proposal_version);
2554 out_free:
2555 	kfree(ini);
2556 	kfree(buf);
2557 }
2558 
2559 static void smc_tcp_listen_work(struct work_struct *work)
2560 {
2561 	struct smc_sock *lsmc = container_of(work, struct smc_sock,
2562 					     tcp_listen_work);
2563 	struct sock *lsk = &lsmc->sk;
2564 	struct smc_sock *new_smc;
2565 	int rc = 0;
2566 
2567 	lock_sock(lsk);
2568 	while (lsk->sk_state == SMC_LISTEN) {
2569 		rc = smc_clcsock_accept(lsmc, &new_smc);
2570 		if (rc) /* clcsock accept queue empty or error */
2571 			goto out;
2572 		if (!new_smc)
2573 			continue;
2574 
2575 		if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2576 			atomic_inc(&lsmc->queued_smc_hs);
2577 
2578 		new_smc->listen_smc = lsmc;
2579 		new_smc->use_fallback = lsmc->use_fallback;
2580 		new_smc->fallback_rsn = lsmc->fallback_rsn;
2581 		sock_hold(lsk); /* sock_put in smc_listen_work */
2582 		INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2583 		smc_copy_sock_settings_to_smc(new_smc);
2584 		sock_hold(&new_smc->sk); /* sock_put in passive closing */
2585 		if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2586 			sock_put(&new_smc->sk);
2587 	}
2588 
2589 out:
2590 	release_sock(lsk);
2591 	sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2592 }
2593 
2594 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2595 {
2596 	struct smc_sock *lsmc;
2597 
2598 	read_lock_bh(&listen_clcsock->sk_callback_lock);
2599 	lsmc = smc_clcsock_user_data(listen_clcsock);
2600 	if (!lsmc)
2601 		goto out;
2602 	lsmc->clcsk_data_ready(listen_clcsock);
2603 	if (lsmc->sk.sk_state == SMC_LISTEN) {
2604 		sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2605 		if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2606 			sock_put(&lsmc->sk);
2607 	}
2608 out:
2609 	read_unlock_bh(&listen_clcsock->sk_callback_lock);
2610 }
2611 
2612 int smc_listen(struct socket *sock, int backlog)
2613 {
2614 	struct sock *sk = sock->sk;
2615 	struct smc_sock *smc;
2616 	int rc;
2617 
2618 	smc = smc_sk(sk);
2619 	lock_sock(sk);
2620 
2621 	rc = -EINVAL;
2622 	if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2623 	    smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2624 		goto out;
2625 
2626 	rc = 0;
2627 	if (sk->sk_state == SMC_LISTEN) {
2628 		sk->sk_max_ack_backlog = backlog;
2629 		goto out;
2630 	}
2631 	/* some socket options are handled in core, so we could not apply
2632 	 * them to the clc socket -- copy smc socket options to clc socket
2633 	 */
2634 	smc_copy_sock_settings_to_clc(smc);
2635 	if (!smc->use_fallback)
2636 		tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2637 
2638 	/* save original sk_data_ready function and establish
2639 	 * smc-specific sk_data_ready function
2640 	 */
2641 	write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2642 	smc->clcsock->sk->sk_user_data =
2643 		(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2644 	smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2645 			       smc_clcsock_data_ready, &smc->clcsk_data_ready);
2646 	write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2647 
2648 	/* save original ops */
2649 	smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2650 
2651 	smc->af_ops = *smc->ori_af_ops;
2652 	smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2653 
2654 	inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2655 
2656 	if (smc->limit_smc_hs)
2657 		tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2658 
2659 	rc = kernel_listen(smc->clcsock, backlog);
2660 	if (rc) {
2661 		write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2662 		smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2663 				       &smc->clcsk_data_ready);
2664 		smc->clcsock->sk->sk_user_data = NULL;
2665 		write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2666 		goto out;
2667 	}
2668 	sk->sk_max_ack_backlog = backlog;
2669 	sk->sk_ack_backlog = 0;
2670 	sk->sk_state = SMC_LISTEN;
2671 
2672 out:
2673 	release_sock(sk);
2674 	return rc;
2675 }
2676 
2677 int smc_accept(struct socket *sock, struct socket *new_sock,
2678 	       struct proto_accept_arg *arg)
2679 {
2680 	struct sock *sk = sock->sk, *nsk;
2681 	DECLARE_WAITQUEUE(wait, current);
2682 	struct smc_sock *lsmc;
2683 	long timeo;
2684 	int rc = 0;
2685 
2686 	lsmc = smc_sk(sk);
2687 	sock_hold(sk); /* sock_put below */
2688 	lock_sock(sk);
2689 
2690 	if (lsmc->sk.sk_state != SMC_LISTEN) {
2691 		rc = -EINVAL;
2692 		release_sock(sk);
2693 		goto out;
2694 	}
2695 
2696 	/* Wait for an incoming connection */
2697 	timeo = sock_rcvtimeo(sk, arg->flags & O_NONBLOCK);
2698 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
2699 	while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2700 		set_current_state(TASK_INTERRUPTIBLE);
2701 		if (!timeo) {
2702 			rc = -EAGAIN;
2703 			break;
2704 		}
2705 		release_sock(sk);
2706 		timeo = schedule_timeout(timeo);
2707 		/* wakeup by sk_data_ready in smc_listen_work() */
2708 		sched_annotate_sleep();
2709 		lock_sock(sk);
2710 		if (signal_pending(current)) {
2711 			rc = sock_intr_errno(timeo);
2712 			break;
2713 		}
2714 	}
2715 	set_current_state(TASK_RUNNING);
2716 	remove_wait_queue(sk_sleep(sk), &wait);
2717 
2718 	if (!rc)
2719 		rc = sock_error(nsk);
2720 	release_sock(sk);
2721 	if (rc)
2722 		goto out;
2723 
2724 	if (lsmc->sockopt_defer_accept && !(arg->flags & O_NONBLOCK)) {
2725 		/* wait till data arrives on the socket */
2726 		timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2727 								MSEC_PER_SEC);
2728 		if (smc_sk(nsk)->use_fallback) {
2729 			struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2730 
2731 			lock_sock(clcsk);
2732 			if (skb_queue_empty(&clcsk->sk_receive_queue))
2733 				sk_wait_data(clcsk, &timeo, NULL);
2734 			release_sock(clcsk);
2735 		} else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2736 			lock_sock(nsk);
2737 			smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2738 			release_sock(nsk);
2739 		}
2740 	}
2741 
2742 out:
2743 	sock_put(sk); /* sock_hold above */
2744 	return rc;
2745 }
2746 
2747 int smc_getname(struct socket *sock, struct sockaddr *addr,
2748 		int peer)
2749 {
2750 	struct smc_sock *smc;
2751 
2752 	if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2753 	    (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2754 		return -ENOTCONN;
2755 
2756 	smc = smc_sk(sock->sk);
2757 
2758 	return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2759 }
2760 
2761 int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2762 {
2763 	struct sock *sk = sock->sk;
2764 	struct smc_sock *smc;
2765 	int rc;
2766 
2767 	smc = smc_sk(sk);
2768 	lock_sock(sk);
2769 
2770 	/* SMC does not support connect with fastopen */
2771 	if (msg->msg_flags & MSG_FASTOPEN) {
2772 		/* not connected yet, fallback */
2773 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2774 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2775 			if (rc)
2776 				goto out;
2777 		} else {
2778 			rc = -EINVAL;
2779 			goto out;
2780 		}
2781 	} else if ((sk->sk_state != SMC_ACTIVE) &&
2782 		   (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2783 		   (sk->sk_state != SMC_INIT)) {
2784 		rc = -EPIPE;
2785 		goto out;
2786 	}
2787 
2788 	if (smc->use_fallback) {
2789 		rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2790 	} else {
2791 		rc = smc_tx_sendmsg(smc, msg, len);
2792 		SMC_STAT_TX_PAYLOAD(smc, len, rc);
2793 	}
2794 out:
2795 	release_sock(sk);
2796 	return rc;
2797 }
2798 
2799 int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2800 		int flags)
2801 {
2802 	struct sock *sk = sock->sk;
2803 	struct smc_sock *smc;
2804 	int rc = -ENOTCONN;
2805 
2806 	smc = smc_sk(sk);
2807 	lock_sock(sk);
2808 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2809 		/* socket was connected before, no more data to read */
2810 		rc = 0;
2811 		goto out;
2812 	}
2813 	if ((sk->sk_state == SMC_INIT) ||
2814 	    (sk->sk_state == SMC_LISTEN) ||
2815 	    (sk->sk_state == SMC_CLOSED))
2816 		goto out;
2817 
2818 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2819 		rc = 0;
2820 		goto out;
2821 	}
2822 
2823 	if (smc->use_fallback) {
2824 		rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2825 	} else {
2826 		msg->msg_namelen = 0;
2827 		rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2828 		SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2829 	}
2830 
2831 out:
2832 	release_sock(sk);
2833 	return rc;
2834 }
2835 
2836 static __poll_t smc_accept_poll(struct sock *parent)
2837 {
2838 	struct smc_sock *isk = smc_sk(parent);
2839 	__poll_t mask = 0;
2840 
2841 	spin_lock(&isk->accept_q_lock);
2842 	if (!list_empty(&isk->accept_q))
2843 		mask = EPOLLIN | EPOLLRDNORM;
2844 	spin_unlock(&isk->accept_q_lock);
2845 
2846 	return mask;
2847 }
2848 
2849 __poll_t smc_poll(struct file *file, struct socket *sock,
2850 		  poll_table *wait)
2851 {
2852 	struct sock *sk = sock->sk;
2853 	struct smc_sock *smc;
2854 	__poll_t mask = 0;
2855 
2856 	if (!sk)
2857 		return EPOLLNVAL;
2858 
2859 	smc = smc_sk(sock->sk);
2860 	if (smc->use_fallback) {
2861 		/* delegate to CLC child sock */
2862 		mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2863 		sk->sk_err = smc->clcsock->sk->sk_err;
2864 	} else {
2865 		if (sk->sk_state != SMC_CLOSED)
2866 			sock_poll_wait(file, sock, wait);
2867 		if (sk->sk_err)
2868 			mask |= EPOLLERR;
2869 		if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2870 		    (sk->sk_state == SMC_CLOSED))
2871 			mask |= EPOLLHUP;
2872 		if (sk->sk_state == SMC_LISTEN) {
2873 			/* woken up by sk_data_ready in smc_listen_work() */
2874 			mask |= smc_accept_poll(sk);
2875 		} else if (smc->use_fallback) { /* as result of connect_work()*/
2876 			mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2877 							   wait);
2878 			sk->sk_err = smc->clcsock->sk->sk_err;
2879 		} else {
2880 			if ((sk->sk_state != SMC_INIT &&
2881 			     atomic_read(&smc->conn.sndbuf_space)) ||
2882 			    sk->sk_shutdown & SEND_SHUTDOWN) {
2883 				mask |= EPOLLOUT | EPOLLWRNORM;
2884 			} else {
2885 				sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2886 				set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2887 			}
2888 			if (atomic_read(&smc->conn.bytes_to_rcv))
2889 				mask |= EPOLLIN | EPOLLRDNORM;
2890 			if (sk->sk_shutdown & RCV_SHUTDOWN)
2891 				mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2892 			if (sk->sk_state == SMC_APPCLOSEWAIT1)
2893 				mask |= EPOLLIN;
2894 			if (smc->conn.urg_state == SMC_URG_VALID)
2895 				mask |= EPOLLPRI;
2896 		}
2897 	}
2898 
2899 	return mask;
2900 }
2901 
2902 int smc_shutdown(struct socket *sock, int how)
2903 {
2904 	struct sock *sk = sock->sk;
2905 	bool do_shutdown = true;
2906 	struct smc_sock *smc;
2907 	int rc = -EINVAL;
2908 	int old_state;
2909 	int rc1 = 0;
2910 
2911 	smc = smc_sk(sk);
2912 
2913 	if ((how < SHUT_RD) || (how > SHUT_RDWR))
2914 		return rc;
2915 
2916 	lock_sock(sk);
2917 
2918 	if (sock->state == SS_CONNECTING) {
2919 		if (sk->sk_state == SMC_ACTIVE)
2920 			sock->state = SS_CONNECTED;
2921 		else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2922 			 sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2923 			 sk->sk_state == SMC_APPCLOSEWAIT1 ||
2924 			 sk->sk_state == SMC_APPCLOSEWAIT2 ||
2925 			 sk->sk_state == SMC_APPFINCLOSEWAIT)
2926 			sock->state = SS_DISCONNECTING;
2927 	}
2928 
2929 	rc = -ENOTCONN;
2930 	if ((sk->sk_state != SMC_ACTIVE) &&
2931 	    (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2932 	    (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2933 	    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2934 	    (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2935 	    (sk->sk_state != SMC_APPFINCLOSEWAIT))
2936 		goto out;
2937 	if (smc->use_fallback) {
2938 		rc = kernel_sock_shutdown(smc->clcsock, how);
2939 		sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2940 		if (sk->sk_shutdown == SHUTDOWN_MASK) {
2941 			sk->sk_state = SMC_CLOSED;
2942 			sk->sk_socket->state = SS_UNCONNECTED;
2943 			sock_put(sk);
2944 		}
2945 		goto out;
2946 	}
2947 	switch (how) {
2948 	case SHUT_RDWR:		/* shutdown in both directions */
2949 		old_state = sk->sk_state;
2950 		rc = smc_close_active(smc);
2951 		if (old_state == SMC_ACTIVE &&
2952 		    sk->sk_state == SMC_PEERCLOSEWAIT1)
2953 			do_shutdown = false;
2954 		break;
2955 	case SHUT_WR:
2956 		rc = smc_close_shutdown_write(smc);
2957 		break;
2958 	case SHUT_RD:
2959 		rc = 0;
2960 		/* nothing more to do because peer is not involved */
2961 		break;
2962 	}
2963 	if (do_shutdown && smc->clcsock)
2964 		rc1 = kernel_sock_shutdown(smc->clcsock, how);
2965 	/* map sock_shutdown_cmd constants to sk_shutdown value range */
2966 	sk->sk_shutdown |= how + 1;
2967 
2968 	if (sk->sk_state == SMC_CLOSED)
2969 		sock->state = SS_UNCONNECTED;
2970 	else
2971 		sock->state = SS_DISCONNECTING;
2972 out:
2973 	release_sock(sk);
2974 	return rc ? rc : rc1;
2975 }
2976 
2977 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2978 			    char __user *optval, int __user *optlen)
2979 {
2980 	struct smc_sock *smc;
2981 	int val, len;
2982 
2983 	smc = smc_sk(sock->sk);
2984 
2985 	if (get_user(len, optlen))
2986 		return -EFAULT;
2987 
2988 	len = min_t(int, len, sizeof(int));
2989 
2990 	if (len < 0)
2991 		return -EINVAL;
2992 
2993 	switch (optname) {
2994 	case SMC_LIMIT_HS:
2995 		val = smc->limit_smc_hs;
2996 		break;
2997 	default:
2998 		return -EOPNOTSUPP;
2999 	}
3000 
3001 	if (put_user(len, optlen))
3002 		return -EFAULT;
3003 	if (copy_to_user(optval, &val, len))
3004 		return -EFAULT;
3005 
3006 	return 0;
3007 }
3008 
3009 static int __smc_setsockopt(struct socket *sock, int level, int optname,
3010 			    sockptr_t optval, unsigned int optlen)
3011 {
3012 	struct sock *sk = sock->sk;
3013 	struct smc_sock *smc;
3014 	int val, rc;
3015 
3016 	smc = smc_sk(sk);
3017 
3018 	lock_sock(sk);
3019 	switch (optname) {
3020 	case SMC_LIMIT_HS:
3021 		if (optlen < sizeof(int)) {
3022 			rc = -EINVAL;
3023 			break;
3024 		}
3025 		if (copy_from_sockptr(&val, optval, sizeof(int))) {
3026 			rc = -EFAULT;
3027 			break;
3028 		}
3029 
3030 		smc->limit_smc_hs = !!val;
3031 		rc = 0;
3032 		break;
3033 	default:
3034 		rc = -EOPNOTSUPP;
3035 		break;
3036 	}
3037 	release_sock(sk);
3038 
3039 	return rc;
3040 }
3041 
3042 int smc_setsockopt(struct socket *sock, int level, int optname,
3043 		   sockptr_t optval, unsigned int optlen)
3044 {
3045 	struct sock *sk = sock->sk;
3046 	struct smc_sock *smc;
3047 	int val, rc;
3048 
3049 	if (level == SOL_TCP && optname == TCP_ULP)
3050 		return -EOPNOTSUPP;
3051 	else if (level == SOL_SMC)
3052 		return __smc_setsockopt(sock, level, optname, optval, optlen);
3053 
3054 	smc = smc_sk(sk);
3055 
3056 	/* generic setsockopts reaching us here always apply to the
3057 	 * CLC socket
3058 	 */
3059 	mutex_lock(&smc->clcsock_release_lock);
3060 	if (!smc->clcsock) {
3061 		mutex_unlock(&smc->clcsock_release_lock);
3062 		return -EBADF;
3063 	}
3064 	if (unlikely(!smc->clcsock->ops->setsockopt))
3065 		rc = -EOPNOTSUPP;
3066 	else
3067 		rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
3068 						   optval, optlen);
3069 	if (smc->clcsock->sk->sk_err) {
3070 		sk->sk_err = smc->clcsock->sk->sk_err;
3071 		sk_error_report(sk);
3072 	}
3073 	mutex_unlock(&smc->clcsock_release_lock);
3074 
3075 	if (optlen < sizeof(int))
3076 		return -EINVAL;
3077 	if (copy_from_sockptr(&val, optval, sizeof(int)))
3078 		return -EFAULT;
3079 
3080 	lock_sock(sk);
3081 	if (rc || smc->use_fallback)
3082 		goto out;
3083 	switch (optname) {
3084 	case TCP_FASTOPEN:
3085 	case TCP_FASTOPEN_CONNECT:
3086 	case TCP_FASTOPEN_KEY:
3087 	case TCP_FASTOPEN_NO_COOKIE:
3088 		/* option not supported by SMC */
3089 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
3090 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
3091 		} else {
3092 			rc = -EINVAL;
3093 		}
3094 		break;
3095 	case TCP_NODELAY:
3096 		if (sk->sk_state != SMC_INIT &&
3097 		    sk->sk_state != SMC_LISTEN &&
3098 		    sk->sk_state != SMC_CLOSED) {
3099 			if (val) {
3100 				SMC_STAT_INC(smc, ndly_cnt);
3101 				smc_tx_pending(&smc->conn);
3102 				cancel_delayed_work(&smc->conn.tx_work);
3103 			}
3104 		}
3105 		break;
3106 	case TCP_CORK:
3107 		if (sk->sk_state != SMC_INIT &&
3108 		    sk->sk_state != SMC_LISTEN &&
3109 		    sk->sk_state != SMC_CLOSED) {
3110 			if (!val) {
3111 				SMC_STAT_INC(smc, cork_cnt);
3112 				smc_tx_pending(&smc->conn);
3113 				cancel_delayed_work(&smc->conn.tx_work);
3114 			}
3115 		}
3116 		break;
3117 	case TCP_DEFER_ACCEPT:
3118 		smc->sockopt_defer_accept = val;
3119 		break;
3120 	default:
3121 		break;
3122 	}
3123 out:
3124 	release_sock(sk);
3125 
3126 	return rc;
3127 }
3128 
3129 int smc_getsockopt(struct socket *sock, int level, int optname,
3130 		   char __user *optval, int __user *optlen)
3131 {
3132 	struct smc_sock *smc;
3133 	int rc;
3134 
3135 	if (level == SOL_SMC)
3136 		return __smc_getsockopt(sock, level, optname, optval, optlen);
3137 
3138 	smc = smc_sk(sock->sk);
3139 	mutex_lock(&smc->clcsock_release_lock);
3140 	if (!smc->clcsock) {
3141 		mutex_unlock(&smc->clcsock_release_lock);
3142 		return -EBADF;
3143 	}
3144 	/* socket options apply to the CLC socket */
3145 	if (unlikely(!smc->clcsock->ops->getsockopt)) {
3146 		mutex_unlock(&smc->clcsock_release_lock);
3147 		return -EOPNOTSUPP;
3148 	}
3149 	rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3150 					   optval, optlen);
3151 	mutex_unlock(&smc->clcsock_release_lock);
3152 	return rc;
3153 }
3154 
3155 int smc_ioctl(struct socket *sock, unsigned int cmd,
3156 	      unsigned long arg)
3157 {
3158 	union smc_host_cursor cons, urg;
3159 	struct smc_connection *conn;
3160 	struct smc_sock *smc;
3161 	int answ;
3162 
3163 	smc = smc_sk(sock->sk);
3164 	conn = &smc->conn;
3165 	lock_sock(&smc->sk);
3166 	if (smc->use_fallback) {
3167 		if (!smc->clcsock) {
3168 			release_sock(&smc->sk);
3169 			return -EBADF;
3170 		}
3171 		answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3172 		release_sock(&smc->sk);
3173 		return answ;
3174 	}
3175 	switch (cmd) {
3176 	case SIOCINQ: /* same as FIONREAD */
3177 		if (smc->sk.sk_state == SMC_LISTEN) {
3178 			release_sock(&smc->sk);
3179 			return -EINVAL;
3180 		}
3181 		if (smc->sk.sk_state == SMC_INIT ||
3182 		    smc->sk.sk_state == SMC_CLOSED)
3183 			answ = 0;
3184 		else
3185 			answ = atomic_read(&smc->conn.bytes_to_rcv);
3186 		break;
3187 	case SIOCOUTQ:
3188 		/* output queue size (not send + not acked) */
3189 		if (smc->sk.sk_state == SMC_LISTEN) {
3190 			release_sock(&smc->sk);
3191 			return -EINVAL;
3192 		}
3193 		if (smc->sk.sk_state == SMC_INIT ||
3194 		    smc->sk.sk_state == SMC_CLOSED)
3195 			answ = 0;
3196 		else
3197 			answ = smc->conn.sndbuf_desc->len -
3198 					atomic_read(&smc->conn.sndbuf_space);
3199 		break;
3200 	case SIOCOUTQNSD:
3201 		/* output queue size (not send only) */
3202 		if (smc->sk.sk_state == SMC_LISTEN) {
3203 			release_sock(&smc->sk);
3204 			return -EINVAL;
3205 		}
3206 		if (smc->sk.sk_state == SMC_INIT ||
3207 		    smc->sk.sk_state == SMC_CLOSED)
3208 			answ = 0;
3209 		else
3210 			answ = smc_tx_prepared_sends(&smc->conn);
3211 		break;
3212 	case SIOCATMARK:
3213 		if (smc->sk.sk_state == SMC_LISTEN) {
3214 			release_sock(&smc->sk);
3215 			return -EINVAL;
3216 		}
3217 		if (smc->sk.sk_state == SMC_INIT ||
3218 		    smc->sk.sk_state == SMC_CLOSED) {
3219 			answ = 0;
3220 		} else {
3221 			smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3222 			smc_curs_copy(&urg, &conn->urg_curs, conn);
3223 			answ = smc_curs_diff(conn->rmb_desc->len,
3224 					     &cons, &urg) == 1;
3225 		}
3226 		break;
3227 	default:
3228 		release_sock(&smc->sk);
3229 		return -ENOIOCTLCMD;
3230 	}
3231 	release_sock(&smc->sk);
3232 
3233 	return put_user(answ, (int __user *)arg);
3234 }
3235 
3236 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3237  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3238  * updates till whenever a respective page has been fully processed.
3239  * Note that subsequent recv() calls have to wait till all splice() processing
3240  * completed.
3241  */
3242 ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3243 			struct pipe_inode_info *pipe, size_t len,
3244 			unsigned int flags)
3245 {
3246 	struct sock *sk = sock->sk;
3247 	struct smc_sock *smc;
3248 	int rc = -ENOTCONN;
3249 
3250 	smc = smc_sk(sk);
3251 	lock_sock(sk);
3252 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3253 		/* socket was connected before, no more data to read */
3254 		rc = 0;
3255 		goto out;
3256 	}
3257 	if (sk->sk_state == SMC_INIT ||
3258 	    sk->sk_state == SMC_LISTEN ||
3259 	    sk->sk_state == SMC_CLOSED)
3260 		goto out;
3261 
3262 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3263 		rc = 0;
3264 		goto out;
3265 	}
3266 
3267 	if (smc->use_fallback) {
3268 		rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3269 						    pipe, len, flags);
3270 	} else {
3271 		if (*ppos) {
3272 			rc = -ESPIPE;
3273 			goto out;
3274 		}
3275 		if (flags & SPLICE_F_NONBLOCK)
3276 			flags = MSG_DONTWAIT;
3277 		else
3278 			flags = 0;
3279 		SMC_STAT_INC(smc, splice_cnt);
3280 		rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3281 	}
3282 out:
3283 	release_sock(sk);
3284 
3285 	return rc;
3286 }
3287 
3288 /* must look like tcp */
3289 static const struct proto_ops smc_sock_ops = {
3290 	.family		= PF_SMC,
3291 	.owner		= THIS_MODULE,
3292 	.release	= smc_release,
3293 	.bind		= smc_bind,
3294 	.connect	= smc_connect,
3295 	.socketpair	= sock_no_socketpair,
3296 	.accept		= smc_accept,
3297 	.getname	= smc_getname,
3298 	.poll		= smc_poll,
3299 	.ioctl		= smc_ioctl,
3300 	.listen		= smc_listen,
3301 	.shutdown	= smc_shutdown,
3302 	.setsockopt	= smc_setsockopt,
3303 	.getsockopt	= smc_getsockopt,
3304 	.sendmsg	= smc_sendmsg,
3305 	.recvmsg	= smc_recvmsg,
3306 	.mmap		= sock_no_mmap,
3307 	.splice_read	= smc_splice_read,
3308 };
3309 
3310 int smc_create_clcsk(struct net *net, struct sock *sk, int family)
3311 {
3312 	struct smc_sock *smc = smc_sk(sk);
3313 	int rc;
3314 
3315 	rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3316 			      &smc->clcsock);
3317 	if (rc)
3318 		return rc;
3319 
3320 	/* smc_clcsock_release() does not wait smc->clcsock->sk's
3321 	 * destruction;  its sk_state might not be TCP_CLOSE after
3322 	 * smc->sk is close()d, and TCP timers can be fired later,
3323 	 * which need net ref.
3324 	 */
3325 	sk = smc->clcsock->sk;
3326 	__netns_tracker_free(net, &sk->ns_tracker, false);
3327 	sk->sk_net_refcnt = 1;
3328 	get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
3329 	sock_inuse_add(net, 1);
3330 	return 0;
3331 }
3332 
3333 static int __smc_create(struct net *net, struct socket *sock, int protocol,
3334 			int kern, struct socket *clcsock)
3335 {
3336 	int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3337 	struct smc_sock *smc;
3338 	struct sock *sk;
3339 	int rc;
3340 
3341 	rc = -ESOCKTNOSUPPORT;
3342 	if (sock->type != SOCK_STREAM)
3343 		goto out;
3344 
3345 	rc = -EPROTONOSUPPORT;
3346 	if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3347 		goto out;
3348 
3349 	rc = -ENOBUFS;
3350 	sock->ops = &smc_sock_ops;
3351 	sock->state = SS_UNCONNECTED;
3352 	sk = smc_sock_alloc(net, sock, protocol);
3353 	if (!sk)
3354 		goto out;
3355 
3356 	/* create internal TCP socket for CLC handshake and fallback */
3357 	smc = smc_sk(sk);
3358 
3359 	rc = 0;
3360 	if (clcsock)
3361 		smc->clcsock = clcsock;
3362 	else
3363 		rc = smc_create_clcsk(net, sk, family);
3364 
3365 	if (rc) {
3366 		sk_common_release(sk);
3367 		sock->sk = NULL;
3368 	}
3369 out:
3370 	return rc;
3371 }
3372 
3373 static int smc_create(struct net *net, struct socket *sock, int protocol,
3374 		      int kern)
3375 {
3376 	return __smc_create(net, sock, protocol, kern, NULL);
3377 }
3378 
3379 static const struct net_proto_family smc_sock_family_ops = {
3380 	.family	= PF_SMC,
3381 	.owner	= THIS_MODULE,
3382 	.create	= smc_create,
3383 };
3384 
3385 static int smc_ulp_init(struct sock *sk)
3386 {
3387 	struct socket *tcp = sk->sk_socket;
3388 	struct net *net = sock_net(sk);
3389 	struct socket *smcsock;
3390 	int protocol, ret;
3391 
3392 	/* only TCP can be replaced */
3393 	if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3394 	    (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3395 		return -ESOCKTNOSUPPORT;
3396 	/* don't handle wq now */
3397 	if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3398 		return -ENOTCONN;
3399 
3400 	if (sk->sk_family == AF_INET)
3401 		protocol = SMCPROTO_SMC;
3402 	else
3403 		protocol = SMCPROTO_SMC6;
3404 
3405 	smcsock = sock_alloc();
3406 	if (!smcsock)
3407 		return -ENFILE;
3408 
3409 	smcsock->type = SOCK_STREAM;
3410 	__module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3411 	ret = __smc_create(net, smcsock, protocol, 1, tcp);
3412 	if (ret) {
3413 		sock_release(smcsock); /* module_put() which ops won't be NULL */
3414 		return ret;
3415 	}
3416 
3417 	/* replace tcp socket to smc */
3418 	smcsock->file = tcp->file;
3419 	smcsock->file->private_data = smcsock;
3420 	smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3421 	smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3422 	tcp->file = NULL;
3423 
3424 	return ret;
3425 }
3426 
3427 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3428 			  const gfp_t priority)
3429 {
3430 	struct inet_connection_sock *icsk = inet_csk(newsk);
3431 
3432 	/* don't inherit ulp ops to child when listen */
3433 	icsk->icsk_ulp_ops = NULL;
3434 }
3435 
3436 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3437 	.name		= "smc",
3438 	.owner		= THIS_MODULE,
3439 	.init		= smc_ulp_init,
3440 	.clone		= smc_ulp_clone,
3441 };
3442 
3443 unsigned int smc_net_id;
3444 
3445 static __net_init int smc_net_init(struct net *net)
3446 {
3447 	int rc;
3448 
3449 	rc = smc_sysctl_net_init(net);
3450 	if (rc)
3451 		return rc;
3452 	return smc_pnet_net_init(net);
3453 }
3454 
3455 static void __net_exit smc_net_exit(struct net *net)
3456 {
3457 	smc_sysctl_net_exit(net);
3458 	smc_pnet_net_exit(net);
3459 }
3460 
3461 static __net_init int smc_net_stat_init(struct net *net)
3462 {
3463 	return smc_stats_init(net);
3464 }
3465 
3466 static void __net_exit smc_net_stat_exit(struct net *net)
3467 {
3468 	smc_stats_exit(net);
3469 }
3470 
3471 static struct pernet_operations smc_net_ops = {
3472 	.init = smc_net_init,
3473 	.exit = smc_net_exit,
3474 	.id   = &smc_net_id,
3475 	.size = sizeof(struct smc_net),
3476 };
3477 
3478 static struct pernet_operations smc_net_stat_ops = {
3479 	.init = smc_net_stat_init,
3480 	.exit = smc_net_stat_exit,
3481 };
3482 
3483 static int __init smc_init(void)
3484 {
3485 	int rc;
3486 
3487 	rc = register_pernet_subsys(&smc_net_ops);
3488 	if (rc)
3489 		return rc;
3490 
3491 	rc = register_pernet_subsys(&smc_net_stat_ops);
3492 	if (rc)
3493 		goto out_pernet_subsys;
3494 
3495 	rc = smc_ism_init();
3496 	if (rc)
3497 		goto out_pernet_subsys_stat;
3498 	smc_clc_init();
3499 
3500 	rc = smc_nl_init();
3501 	if (rc)
3502 		goto out_ism;
3503 
3504 	rc = smc_pnet_init();
3505 	if (rc)
3506 		goto out_nl;
3507 
3508 	rc = -ENOMEM;
3509 
3510 	smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3511 	if (!smc_tcp_ls_wq)
3512 		goto out_pnet;
3513 
3514 	smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3515 	if (!smc_hs_wq)
3516 		goto out_alloc_tcp_ls_wq;
3517 
3518 	smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3519 	if (!smc_close_wq)
3520 		goto out_alloc_hs_wq;
3521 
3522 	rc = smc_core_init();
3523 	if (rc) {
3524 		pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3525 		goto out_alloc_wqs;
3526 	}
3527 
3528 	rc = smc_llc_init();
3529 	if (rc) {
3530 		pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3531 		goto out_core;
3532 	}
3533 
3534 	rc = smc_cdc_init();
3535 	if (rc) {
3536 		pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3537 		goto out_core;
3538 	}
3539 
3540 	rc = proto_register(&smc_proto, 1);
3541 	if (rc) {
3542 		pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3543 		goto out_core;
3544 	}
3545 
3546 	rc = proto_register(&smc_proto6, 1);
3547 	if (rc) {
3548 		pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3549 		goto out_proto;
3550 	}
3551 
3552 	rc = sock_register(&smc_sock_family_ops);
3553 	if (rc) {
3554 		pr_err("%s: sock_register fails with %d\n", __func__, rc);
3555 		goto out_proto6;
3556 	}
3557 	INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3558 	INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3559 
3560 	rc = smc_ib_register_client();
3561 	if (rc) {
3562 		pr_err("%s: ib_register fails with %d\n", __func__, rc);
3563 		goto out_sock;
3564 	}
3565 
3566 	rc = smc_loopback_init();
3567 	if (rc) {
3568 		pr_err("%s: smc_loopback_init fails with %d\n", __func__, rc);
3569 		goto out_ib;
3570 	}
3571 
3572 	rc = tcp_register_ulp(&smc_ulp_ops);
3573 	if (rc) {
3574 		pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3575 		goto out_lo;
3576 	}
3577 	rc = smc_inet_init();
3578 	if (rc) {
3579 		pr_err("%s: smc_inet_init fails with %d\n", __func__, rc);
3580 		goto out_ulp;
3581 	}
3582 	static_branch_enable(&tcp_have_smc);
3583 	return 0;
3584 out_ulp:
3585 	tcp_unregister_ulp(&smc_ulp_ops);
3586 out_lo:
3587 	smc_loopback_exit();
3588 out_ib:
3589 	smc_ib_unregister_client();
3590 out_sock:
3591 	sock_unregister(PF_SMC);
3592 out_proto6:
3593 	proto_unregister(&smc_proto6);
3594 out_proto:
3595 	proto_unregister(&smc_proto);
3596 out_core:
3597 	smc_core_exit();
3598 out_alloc_wqs:
3599 	destroy_workqueue(smc_close_wq);
3600 out_alloc_hs_wq:
3601 	destroy_workqueue(smc_hs_wq);
3602 out_alloc_tcp_ls_wq:
3603 	destroy_workqueue(smc_tcp_ls_wq);
3604 out_pnet:
3605 	smc_pnet_exit();
3606 out_nl:
3607 	smc_nl_exit();
3608 out_ism:
3609 	smc_clc_exit();
3610 	smc_ism_exit();
3611 out_pernet_subsys_stat:
3612 	unregister_pernet_subsys(&smc_net_stat_ops);
3613 out_pernet_subsys:
3614 	unregister_pernet_subsys(&smc_net_ops);
3615 
3616 	return rc;
3617 }
3618 
3619 static void __exit smc_exit(void)
3620 {
3621 	static_branch_disable(&tcp_have_smc);
3622 	smc_inet_exit();
3623 	tcp_unregister_ulp(&smc_ulp_ops);
3624 	sock_unregister(PF_SMC);
3625 	smc_core_exit();
3626 	smc_loopback_exit();
3627 	smc_ib_unregister_client();
3628 	smc_ism_exit();
3629 	destroy_workqueue(smc_close_wq);
3630 	destroy_workqueue(smc_tcp_ls_wq);
3631 	destroy_workqueue(smc_hs_wq);
3632 	proto_unregister(&smc_proto6);
3633 	proto_unregister(&smc_proto);
3634 	smc_pnet_exit();
3635 	smc_nl_exit();
3636 	smc_clc_exit();
3637 	unregister_pernet_subsys(&smc_net_stat_ops);
3638 	unregister_pernet_subsys(&smc_net_ops);
3639 	rcu_barrier();
3640 }
3641 
3642 module_init(smc_init);
3643 module_exit(smc_exit);
3644 
3645 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3646 MODULE_DESCRIPTION("smc socket address family");
3647 MODULE_LICENSE("GPL");
3648 MODULE_ALIAS_NETPROTO(PF_SMC);
3649 MODULE_ALIAS_TCP_ULP("smc");
3650 /* 256 for IPPROTO_SMC and 1 for SOCK_STREAM */
3651 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 256, 1);
3652 #if IS_ENABLED(CONFIG_IPV6)
3653 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 256, 1);
3654 #endif /* CONFIG_IPV6 */
3655 MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);
3656