xref: /linux/net/smc/af_smc.c (revision 2697b79a469b68e3ad3640f55284359c1396278d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
4  *
5  *  AF_SMC protocol family socket handler keeping the AF_INET sock address type
6  *  applies to SOCK_STREAM sockets only
7  *  offers an alternative communication option for TCP-protocol sockets
8  *  applicable with RoCE-cards only
9  *
10  *  Initial restrictions:
11  *    - support for alternate links postponed
12  *
13  *  Copyright IBM Corp. 2016, 2018
14  *
15  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
16  *              based on prototype from Frank Blaschka
17  */
18 
19 #define KMSG_COMPONENT "smc"
20 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
21 
22 #include <linux/module.h>
23 #include <linux/socket.h>
24 #include <linux/workqueue.h>
25 #include <linux/in.h>
26 #include <linux/sched/signal.h>
27 #include <linux/if_vlan.h>
28 #include <linux/rcupdate_wait.h>
29 #include <linux/ctype.h>
30 #include <linux/splice.h>
31 
32 #include <net/sock.h>
33 #include <net/tcp.h>
34 #include <net/smc.h>
35 #include <asm/ioctls.h>
36 
37 #include <net/net_namespace.h>
38 #include <net/netns/generic.h>
39 #include "smc_netns.h"
40 
41 #include "smc.h"
42 #include "smc_clc.h"
43 #include "smc_llc.h"
44 #include "smc_cdc.h"
45 #include "smc_core.h"
46 #include "smc_ib.h"
47 #include "smc_ism.h"
48 #include "smc_pnet.h"
49 #include "smc_netlink.h"
50 #include "smc_tx.h"
51 #include "smc_rx.h"
52 #include "smc_close.h"
53 #include "smc_stats.h"
54 #include "smc_tracepoint.h"
55 #include "smc_sysctl.h"
56 #include "smc_loopback.h"
57 
58 static DEFINE_MUTEX(smc_server_lgr_pending);	/* serialize link group
59 						 * creation on server
60 						 */
61 static DEFINE_MUTEX(smc_client_lgr_pending);	/* serialize link group
62 						 * creation on client
63 						 */
64 
65 static struct workqueue_struct	*smc_tcp_ls_wq;	/* wq for tcp listen work */
66 struct workqueue_struct	*smc_hs_wq;	/* wq for handshake work */
67 struct workqueue_struct	*smc_close_wq;	/* wq for close work */
68 
69 static void smc_tcp_listen_work(struct work_struct *);
70 static void smc_connect_work(struct work_struct *);
71 
72 int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb)
73 {
74 	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
75 	void *hdr;
76 
77 	if (cb_ctx->pos[0])
78 		goto out;
79 
80 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
81 			  &smc_gen_nl_family, NLM_F_MULTI,
82 			  SMC_NETLINK_DUMP_HS_LIMITATION);
83 	if (!hdr)
84 		return -ENOMEM;
85 
86 	if (nla_put_u8(skb, SMC_NLA_HS_LIMITATION_ENABLED,
87 		       sock_net(skb->sk)->smc.limit_smc_hs))
88 		goto err;
89 
90 	genlmsg_end(skb, hdr);
91 	cb_ctx->pos[0] = 1;
92 out:
93 	return skb->len;
94 err:
95 	genlmsg_cancel(skb, hdr);
96 	return -EMSGSIZE;
97 }
98 
99 int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
100 {
101 	sock_net(skb->sk)->smc.limit_smc_hs = true;
102 	return 0;
103 }
104 
105 int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
106 {
107 	sock_net(skb->sk)->smc.limit_smc_hs = false;
108 	return 0;
109 }
110 
111 static void smc_set_keepalive(struct sock *sk, int val)
112 {
113 	struct smc_sock *smc = smc_sk(sk);
114 
115 	smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
116 }
117 
118 static struct sock *smc_tcp_syn_recv_sock(const struct sock *sk,
119 					  struct sk_buff *skb,
120 					  struct request_sock *req,
121 					  struct dst_entry *dst,
122 					  struct request_sock *req_unhash,
123 					  bool *own_req)
124 {
125 	struct smc_sock *smc;
126 	struct sock *child;
127 
128 	smc = smc_clcsock_user_data(sk);
129 
130 	if (READ_ONCE(sk->sk_ack_backlog) + atomic_read(&smc->queued_smc_hs) >
131 				sk->sk_max_ack_backlog)
132 		goto drop;
133 
134 	if (sk_acceptq_is_full(&smc->sk)) {
135 		NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
136 		goto drop;
137 	}
138 
139 	/* passthrough to original syn recv sock fct */
140 	child = smc->ori_af_ops->syn_recv_sock(sk, skb, req, dst, req_unhash,
141 					       own_req);
142 	/* child must not inherit smc or its ops */
143 	if (child) {
144 		rcu_assign_sk_user_data(child, NULL);
145 
146 		/* v4-mapped sockets don't inherit parent ops. Don't restore. */
147 		if (inet_csk(child)->icsk_af_ops == inet_csk(sk)->icsk_af_ops)
148 			inet_csk(child)->icsk_af_ops = smc->ori_af_ops;
149 	}
150 	return child;
151 
152 drop:
153 	dst_release(dst);
154 	tcp_listendrop(sk);
155 	return NULL;
156 }
157 
158 static bool smc_hs_congested(const struct sock *sk)
159 {
160 	const struct smc_sock *smc;
161 
162 	smc = smc_clcsock_user_data(sk);
163 
164 	if (!smc)
165 		return true;
166 
167 	if (workqueue_congested(WORK_CPU_UNBOUND, smc_hs_wq))
168 		return true;
169 
170 	return false;
171 }
172 
173 static struct smc_hashinfo smc_v4_hashinfo = {
174 	.lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
175 };
176 
177 static struct smc_hashinfo smc_v6_hashinfo = {
178 	.lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
179 };
180 
181 static int smc_hash_sk(struct sock *sk)
182 {
183 	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
184 	struct hlist_head *head;
185 
186 	head = &h->ht;
187 
188 	write_lock_bh(&h->lock);
189 	sk_add_node(sk, head);
190 	write_unlock_bh(&h->lock);
191 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
192 
193 	return 0;
194 }
195 
196 static void smc_unhash_sk(struct sock *sk)
197 {
198 	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
199 
200 	write_lock_bh(&h->lock);
201 	if (sk_del_node_init(sk))
202 		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
203 	write_unlock_bh(&h->lock);
204 }
205 
206 /* This will be called before user really release sock_lock. So do the
207  * work which we didn't do because of user hold the sock_lock in the
208  * BH context
209  */
210 static void smc_release_cb(struct sock *sk)
211 {
212 	struct smc_sock *smc = smc_sk(sk);
213 
214 	if (smc->conn.tx_in_release_sock) {
215 		smc_tx_pending(&smc->conn);
216 		smc->conn.tx_in_release_sock = false;
217 	}
218 }
219 
220 struct proto smc_proto = {
221 	.name		= "SMC",
222 	.owner		= THIS_MODULE,
223 	.keepalive	= smc_set_keepalive,
224 	.hash		= smc_hash_sk,
225 	.unhash		= smc_unhash_sk,
226 	.release_cb	= smc_release_cb,
227 	.obj_size	= sizeof(struct smc_sock),
228 	.h.smc_hash	= &smc_v4_hashinfo,
229 	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
230 };
231 EXPORT_SYMBOL_GPL(smc_proto);
232 
233 struct proto smc_proto6 = {
234 	.name		= "SMC6",
235 	.owner		= THIS_MODULE,
236 	.keepalive	= smc_set_keepalive,
237 	.hash		= smc_hash_sk,
238 	.unhash		= smc_unhash_sk,
239 	.release_cb	= smc_release_cb,
240 	.obj_size	= sizeof(struct smc_sock),
241 	.h.smc_hash	= &smc_v6_hashinfo,
242 	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
243 };
244 EXPORT_SYMBOL_GPL(smc_proto6);
245 
246 static void smc_fback_restore_callbacks(struct smc_sock *smc)
247 {
248 	struct sock *clcsk = smc->clcsock->sk;
249 
250 	write_lock_bh(&clcsk->sk_callback_lock);
251 	clcsk->sk_user_data = NULL;
252 
253 	smc_clcsock_restore_cb(&clcsk->sk_state_change, &smc->clcsk_state_change);
254 	smc_clcsock_restore_cb(&clcsk->sk_data_ready, &smc->clcsk_data_ready);
255 	smc_clcsock_restore_cb(&clcsk->sk_write_space, &smc->clcsk_write_space);
256 	smc_clcsock_restore_cb(&clcsk->sk_error_report, &smc->clcsk_error_report);
257 
258 	write_unlock_bh(&clcsk->sk_callback_lock);
259 }
260 
261 static void smc_restore_fallback_changes(struct smc_sock *smc)
262 {
263 	if (smc->clcsock->file) { /* non-accepted sockets have no file yet */
264 		smc->clcsock->file->private_data = smc->sk.sk_socket;
265 		smc->clcsock->file = NULL;
266 		smc_fback_restore_callbacks(smc);
267 	}
268 }
269 
270 static int __smc_release(struct smc_sock *smc)
271 {
272 	struct sock *sk = &smc->sk;
273 	int rc = 0;
274 
275 	if (!smc->use_fallback) {
276 		rc = smc_close_active(smc);
277 		smc_sock_set_flag(sk, SOCK_DEAD);
278 		sk->sk_shutdown |= SHUTDOWN_MASK;
279 	} else {
280 		if (sk->sk_state != SMC_CLOSED) {
281 			if (sk->sk_state != SMC_LISTEN &&
282 			    sk->sk_state != SMC_INIT)
283 				sock_put(sk); /* passive closing */
284 			if (sk->sk_state == SMC_LISTEN) {
285 				/* wake up clcsock accept */
286 				rc = kernel_sock_shutdown(smc->clcsock,
287 							  SHUT_RDWR);
288 			}
289 			sk->sk_state = SMC_CLOSED;
290 			sk->sk_state_change(sk);
291 		}
292 		smc_restore_fallback_changes(smc);
293 	}
294 
295 	sk->sk_prot->unhash(sk);
296 
297 	if (sk->sk_state == SMC_CLOSED) {
298 		if (smc->clcsock) {
299 			release_sock(sk);
300 			smc_clcsock_release(smc);
301 			lock_sock(sk);
302 		}
303 		if (!smc->use_fallback)
304 			smc_conn_free(&smc->conn);
305 	}
306 
307 	return rc;
308 }
309 
310 static int smc_release(struct socket *sock)
311 {
312 	struct sock *sk = sock->sk;
313 	struct smc_sock *smc;
314 	int old_state, rc = 0;
315 
316 	if (!sk)
317 		goto out;
318 
319 	sock_hold(sk); /* sock_put below */
320 	smc = smc_sk(sk);
321 
322 	old_state = sk->sk_state;
323 
324 	/* cleanup for a dangling non-blocking connect */
325 	if (smc->connect_nonblock && old_state == SMC_INIT)
326 		tcp_abort(smc->clcsock->sk, ECONNABORTED);
327 
328 	if (cancel_work_sync(&smc->connect_work))
329 		sock_put(&smc->sk); /* sock_hold in smc_connect for passive closing */
330 
331 	if (sk->sk_state == SMC_LISTEN)
332 		/* smc_close_non_accepted() is called and acquires
333 		 * sock lock for child sockets again
334 		 */
335 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
336 	else
337 		lock_sock(sk);
338 
339 	if (old_state == SMC_INIT && sk->sk_state == SMC_ACTIVE &&
340 	    !smc->use_fallback)
341 		smc_close_active_abort(smc);
342 
343 	rc = __smc_release(smc);
344 
345 	/* detach socket */
346 	sock_orphan(sk);
347 	sock->sk = NULL;
348 	release_sock(sk);
349 
350 	sock_put(sk); /* sock_hold above */
351 	sock_put(sk); /* final sock_put */
352 out:
353 	return rc;
354 }
355 
356 static void smc_destruct(struct sock *sk)
357 {
358 	if (sk->sk_state != SMC_CLOSED)
359 		return;
360 	if (!sock_flag(sk, SOCK_DEAD))
361 		return;
362 }
363 
364 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
365 				   int protocol)
366 {
367 	struct smc_sock *smc;
368 	struct proto *prot;
369 	struct sock *sk;
370 
371 	prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
372 	sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
373 	if (!sk)
374 		return NULL;
375 
376 	sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
377 	sk->sk_state = SMC_INIT;
378 	sk->sk_destruct = smc_destruct;
379 	sk->sk_protocol = protocol;
380 	WRITE_ONCE(sk->sk_sndbuf, 2 * READ_ONCE(net->smc.sysctl_wmem));
381 	WRITE_ONCE(sk->sk_rcvbuf, 2 * READ_ONCE(net->smc.sysctl_rmem));
382 	smc = smc_sk(sk);
383 	INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
384 	INIT_WORK(&smc->connect_work, smc_connect_work);
385 	INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
386 	INIT_LIST_HEAD(&smc->accept_q);
387 	spin_lock_init(&smc->accept_q_lock);
388 	spin_lock_init(&smc->conn.send_lock);
389 	sk->sk_prot->hash(sk);
390 	mutex_init(&smc->clcsock_release_lock);
391 	smc_init_saved_callbacks(smc);
392 
393 	return sk;
394 }
395 
396 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
397 		    int addr_len)
398 {
399 	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
400 	struct sock *sk = sock->sk;
401 	struct smc_sock *smc;
402 	int rc;
403 
404 	smc = smc_sk(sk);
405 
406 	/* replicate tests from inet_bind(), to be safe wrt. future changes */
407 	rc = -EINVAL;
408 	if (addr_len < sizeof(struct sockaddr_in))
409 		goto out;
410 
411 	rc = -EAFNOSUPPORT;
412 	if (addr->sin_family != AF_INET &&
413 	    addr->sin_family != AF_INET6 &&
414 	    addr->sin_family != AF_UNSPEC)
415 		goto out;
416 	/* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
417 	if (addr->sin_family == AF_UNSPEC &&
418 	    addr->sin_addr.s_addr != htonl(INADDR_ANY))
419 		goto out;
420 
421 	lock_sock(sk);
422 
423 	/* Check if socket is already active */
424 	rc = -EINVAL;
425 	if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
426 		goto out_rel;
427 
428 	smc->clcsock->sk->sk_reuse = sk->sk_reuse;
429 	smc->clcsock->sk->sk_reuseport = sk->sk_reuseport;
430 	rc = kernel_bind(smc->clcsock, uaddr, addr_len);
431 
432 out_rel:
433 	release_sock(sk);
434 out:
435 	return rc;
436 }
437 
438 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
439  * clc socket (since smc is not called for these options from net/core)
440  */
441 
442 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
443 			     (1UL << SOCK_KEEPOPEN) | \
444 			     (1UL << SOCK_LINGER) | \
445 			     (1UL << SOCK_BROADCAST) | \
446 			     (1UL << SOCK_TIMESTAMP) | \
447 			     (1UL << SOCK_DBG) | \
448 			     (1UL << SOCK_RCVTSTAMP) | \
449 			     (1UL << SOCK_RCVTSTAMPNS) | \
450 			     (1UL << SOCK_LOCALROUTE) | \
451 			     (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
452 			     (1UL << SOCK_RXQ_OVFL) | \
453 			     (1UL << SOCK_WIFI_STATUS) | \
454 			     (1UL << SOCK_NOFCS) | \
455 			     (1UL << SOCK_FILTER_LOCKED) | \
456 			     (1UL << SOCK_TSTAMP_NEW))
457 
458 /* if set, use value set by setsockopt() - else use IPv4 or SMC sysctl value */
459 static void smc_adjust_sock_bufsizes(struct sock *nsk, struct sock *osk,
460 				     unsigned long mask)
461 {
462 	nsk->sk_userlocks = osk->sk_userlocks;
463 	if (osk->sk_userlocks & SOCK_SNDBUF_LOCK)
464 		nsk->sk_sndbuf = osk->sk_sndbuf;
465 	if (osk->sk_userlocks & SOCK_RCVBUF_LOCK)
466 		nsk->sk_rcvbuf = osk->sk_rcvbuf;
467 }
468 
469 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
470 				   unsigned long mask)
471 {
472 	/* options we don't get control via setsockopt for */
473 	nsk->sk_type = osk->sk_type;
474 	nsk->sk_sndtimeo = osk->sk_sndtimeo;
475 	nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
476 	nsk->sk_mark = READ_ONCE(osk->sk_mark);
477 	nsk->sk_priority = READ_ONCE(osk->sk_priority);
478 	nsk->sk_rcvlowat = osk->sk_rcvlowat;
479 	nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
480 	nsk->sk_err = osk->sk_err;
481 
482 	nsk->sk_flags &= ~mask;
483 	nsk->sk_flags |= osk->sk_flags & mask;
484 
485 	smc_adjust_sock_bufsizes(nsk, osk, mask);
486 }
487 
488 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
489 {
490 	smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
491 }
492 
493 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
494 			     (1UL << SOCK_KEEPOPEN) | \
495 			     (1UL << SOCK_LINGER) | \
496 			     (1UL << SOCK_DBG))
497 /* copy only settings and flags relevant for smc from clc to smc socket */
498 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
499 {
500 	smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
501 }
502 
503 /* register the new vzalloced sndbuf on all links */
504 static int smcr_lgr_reg_sndbufs(struct smc_link *link,
505 				struct smc_buf_desc *snd_desc)
506 {
507 	struct smc_link_group *lgr = link->lgr;
508 	int i, rc = 0;
509 
510 	if (!snd_desc->is_vm)
511 		return -EINVAL;
512 
513 	/* protect against parallel smcr_link_reg_buf() */
514 	down_write(&lgr->llc_conf_mutex);
515 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
516 		if (!smc_link_active(&lgr->lnk[i]))
517 			continue;
518 		rc = smcr_link_reg_buf(&lgr->lnk[i], snd_desc);
519 		if (rc)
520 			break;
521 	}
522 	up_write(&lgr->llc_conf_mutex);
523 	return rc;
524 }
525 
526 /* register the new rmb on all links */
527 static int smcr_lgr_reg_rmbs(struct smc_link *link,
528 			     struct smc_buf_desc *rmb_desc)
529 {
530 	struct smc_link_group *lgr = link->lgr;
531 	bool do_slow = false;
532 	int i, rc = 0;
533 
534 	rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
535 	if (rc)
536 		return rc;
537 
538 	down_read(&lgr->llc_conf_mutex);
539 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
540 		if (!smc_link_active(&lgr->lnk[i]))
541 			continue;
542 		if (!rmb_desc->is_reg_mr[link->link_idx]) {
543 			up_read(&lgr->llc_conf_mutex);
544 			goto slow_path;
545 		}
546 	}
547 	/* mr register already */
548 	goto fast_path;
549 slow_path:
550 	do_slow = true;
551 	/* protect against parallel smc_llc_cli_rkey_exchange() and
552 	 * parallel smcr_link_reg_buf()
553 	 */
554 	down_write(&lgr->llc_conf_mutex);
555 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
556 		if (!smc_link_active(&lgr->lnk[i]))
557 			continue;
558 		rc = smcr_link_reg_buf(&lgr->lnk[i], rmb_desc);
559 		if (rc)
560 			goto out;
561 	}
562 fast_path:
563 	/* exchange confirm_rkey msg with peer */
564 	rc = smc_llc_do_confirm_rkey(link, rmb_desc);
565 	if (rc) {
566 		rc = -EFAULT;
567 		goto out;
568 	}
569 	rmb_desc->is_conf_rkey = true;
570 out:
571 	do_slow ? up_write(&lgr->llc_conf_mutex) : up_read(&lgr->llc_conf_mutex);
572 	smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
573 	return rc;
574 }
575 
576 static int smcr_clnt_conf_first_link(struct smc_sock *smc)
577 {
578 	struct smc_link *link = smc->conn.lnk;
579 	struct smc_llc_qentry *qentry;
580 	int rc;
581 
582 	/* Receive CONFIRM LINK request from server over RoCE fabric.
583 	 * Increasing the client's timeout by twice as much as the server's
584 	 * timeout by default can temporarily avoid decline messages of
585 	 * both sides crossing or colliding
586 	 */
587 	qentry = smc_llc_wait(link->lgr, NULL, 2 * SMC_LLC_WAIT_TIME,
588 			      SMC_LLC_CONFIRM_LINK);
589 	if (!qentry) {
590 		struct smc_clc_msg_decline dclc;
591 
592 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
593 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
594 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
595 	}
596 	smc_llc_save_peer_uid(qentry);
597 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
598 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
599 	if (rc)
600 		return SMC_CLC_DECL_RMBE_EC;
601 
602 	rc = smc_ib_modify_qp_rts(link);
603 	if (rc)
604 		return SMC_CLC_DECL_ERR_RDYLNK;
605 
606 	smc_wr_remember_qp_attr(link);
607 
608 	/* reg the sndbuf if it was vzalloced */
609 	if (smc->conn.sndbuf_desc->is_vm) {
610 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
611 			return SMC_CLC_DECL_ERR_REGBUF;
612 	}
613 
614 	/* reg the rmb */
615 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
616 		return SMC_CLC_DECL_ERR_REGBUF;
617 
618 	/* confirm_rkey is implicit on 1st contact */
619 	smc->conn.rmb_desc->is_conf_rkey = true;
620 
621 	/* send CONFIRM LINK response over RoCE fabric */
622 	rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
623 	if (rc < 0)
624 		return SMC_CLC_DECL_TIMEOUT_CL;
625 
626 	smc_llc_link_active(link);
627 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
628 
629 	if (link->lgr->max_links > 1) {
630 		/* optional 2nd link, receive ADD LINK request from server */
631 		qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
632 				      SMC_LLC_ADD_LINK);
633 		if (!qentry) {
634 			struct smc_clc_msg_decline dclc;
635 
636 			rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
637 					      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
638 			if (rc == -EAGAIN)
639 				rc = 0; /* no DECLINE received, go with one link */
640 			return rc;
641 		}
642 		smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
643 		smc_llc_cli_add_link(link, qentry);
644 	}
645 	return 0;
646 }
647 
648 static bool smc_isascii(char *hostname)
649 {
650 	int i;
651 
652 	for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
653 		if (!isascii(hostname[i]))
654 			return false;
655 	return true;
656 }
657 
658 static void smc_conn_save_peer_info_fce(struct smc_sock *smc,
659 					struct smc_clc_msg_accept_confirm *clc)
660 {
661 	struct smc_clc_first_contact_ext *fce;
662 	int clc_v2_len;
663 
664 	if (clc->hdr.version == SMC_V1 ||
665 	    !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
666 		return;
667 
668 	if (smc->conn.lgr->is_smcd) {
669 		memcpy(smc->conn.lgr->negotiated_eid, clc->d1.eid,
670 		       SMC_MAX_EID_LEN);
671 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm, d1);
672 	} else {
673 		memcpy(smc->conn.lgr->negotiated_eid, clc->r1.eid,
674 		       SMC_MAX_EID_LEN);
675 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm, r1);
676 	}
677 	fce = (struct smc_clc_first_contact_ext *)(((u8 *)clc) + clc_v2_len);
678 	smc->conn.lgr->peer_os = fce->os_type;
679 	smc->conn.lgr->peer_smc_release = fce->release;
680 	if (smc_isascii(fce->hostname))
681 		memcpy(smc->conn.lgr->peer_hostname, fce->hostname,
682 		       SMC_MAX_HOSTNAME_LEN);
683 }
684 
685 static void smcr_conn_save_peer_info(struct smc_sock *smc,
686 				     struct smc_clc_msg_accept_confirm *clc)
687 {
688 	int bufsize = smc_uncompress_bufsize(clc->r0.rmbe_size);
689 
690 	smc->conn.peer_rmbe_idx = clc->r0.rmbe_idx;
691 	smc->conn.local_tx_ctrl.token = ntohl(clc->r0.rmbe_alert_token);
692 	smc->conn.peer_rmbe_size = bufsize;
693 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
694 	smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
695 }
696 
697 static void smcd_conn_save_peer_info(struct smc_sock *smc,
698 				     struct smc_clc_msg_accept_confirm *clc)
699 {
700 	int bufsize = smc_uncompress_bufsize(clc->d0.dmbe_size);
701 
702 	smc->conn.peer_rmbe_idx = clc->d0.dmbe_idx;
703 	smc->conn.peer_token = ntohll(clc->d0.token);
704 	/* msg header takes up space in the buffer */
705 	smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
706 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
707 	smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
708 }
709 
710 static void smc_conn_save_peer_info(struct smc_sock *smc,
711 				    struct smc_clc_msg_accept_confirm *clc)
712 {
713 	if (smc->conn.lgr->is_smcd)
714 		smcd_conn_save_peer_info(smc, clc);
715 	else
716 		smcr_conn_save_peer_info(smc, clc);
717 	smc_conn_save_peer_info_fce(smc, clc);
718 }
719 
720 static void smc_link_save_peer_info(struct smc_link *link,
721 				    struct smc_clc_msg_accept_confirm *clc,
722 				    struct smc_init_info *ini)
723 {
724 	link->peer_qpn = ntoh24(clc->r0.qpn);
725 	memcpy(link->peer_gid, ini->peer_gid, SMC_GID_SIZE);
726 	memcpy(link->peer_mac, ini->peer_mac, sizeof(link->peer_mac));
727 	link->peer_psn = ntoh24(clc->r0.psn);
728 	link->peer_mtu = clc->r0.qp_mtu;
729 }
730 
731 static void smc_stat_inc_fback_rsn_cnt(struct smc_sock *smc,
732 				       struct smc_stats_fback *fback_arr)
733 {
734 	int cnt;
735 
736 	for (cnt = 0; cnt < SMC_MAX_FBACK_RSN_CNT; cnt++) {
737 		if (fback_arr[cnt].fback_code == smc->fallback_rsn) {
738 			fback_arr[cnt].count++;
739 			break;
740 		}
741 		if (!fback_arr[cnt].fback_code) {
742 			fback_arr[cnt].fback_code = smc->fallback_rsn;
743 			fback_arr[cnt].count++;
744 			break;
745 		}
746 	}
747 }
748 
749 static void smc_stat_fallback(struct smc_sock *smc)
750 {
751 	struct net *net = sock_net(&smc->sk);
752 
753 	mutex_lock(&net->smc.mutex_fback_rsn);
754 	if (smc->listen_smc) {
755 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->srv);
756 		net->smc.fback_rsn->srv_fback_cnt++;
757 	} else {
758 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->clnt);
759 		net->smc.fback_rsn->clnt_fback_cnt++;
760 	}
761 	mutex_unlock(&net->smc.mutex_fback_rsn);
762 }
763 
764 /* must be called under rcu read lock */
765 static void smc_fback_wakeup_waitqueue(struct smc_sock *smc, void *key)
766 {
767 	struct socket_wq *wq;
768 	__poll_t flags;
769 
770 	wq = rcu_dereference(smc->sk.sk_wq);
771 	if (!skwq_has_sleeper(wq))
772 		return;
773 
774 	/* wake up smc sk->sk_wq */
775 	if (!key) {
776 		/* sk_state_change */
777 		wake_up_interruptible_all(&wq->wait);
778 	} else {
779 		flags = key_to_poll(key);
780 		if (flags & (EPOLLIN | EPOLLOUT))
781 			/* sk_data_ready or sk_write_space */
782 			wake_up_interruptible_sync_poll(&wq->wait, flags);
783 		else if (flags & EPOLLERR)
784 			/* sk_error_report */
785 			wake_up_interruptible_poll(&wq->wait, flags);
786 	}
787 }
788 
789 static int smc_fback_mark_woken(wait_queue_entry_t *wait,
790 				unsigned int mode, int sync, void *key)
791 {
792 	struct smc_mark_woken *mark =
793 		container_of(wait, struct smc_mark_woken, wait_entry);
794 
795 	mark->woken = true;
796 	mark->key = key;
797 	return 0;
798 }
799 
800 static void smc_fback_forward_wakeup(struct smc_sock *smc, struct sock *clcsk,
801 				     void (*clcsock_callback)(struct sock *sk))
802 {
803 	struct smc_mark_woken mark = { .woken = false };
804 	struct socket_wq *wq;
805 
806 	init_waitqueue_func_entry(&mark.wait_entry,
807 				  smc_fback_mark_woken);
808 	rcu_read_lock();
809 	wq = rcu_dereference(clcsk->sk_wq);
810 	if (!wq)
811 		goto out;
812 	add_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
813 	clcsock_callback(clcsk);
814 	remove_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
815 
816 	if (mark.woken)
817 		smc_fback_wakeup_waitqueue(smc, mark.key);
818 out:
819 	rcu_read_unlock();
820 }
821 
822 static void smc_fback_state_change(struct sock *clcsk)
823 {
824 	struct smc_sock *smc;
825 
826 	read_lock_bh(&clcsk->sk_callback_lock);
827 	smc = smc_clcsock_user_data(clcsk);
828 	if (smc)
829 		smc_fback_forward_wakeup(smc, clcsk,
830 					 smc->clcsk_state_change);
831 	read_unlock_bh(&clcsk->sk_callback_lock);
832 }
833 
834 static void smc_fback_data_ready(struct sock *clcsk)
835 {
836 	struct smc_sock *smc;
837 
838 	read_lock_bh(&clcsk->sk_callback_lock);
839 	smc = smc_clcsock_user_data(clcsk);
840 	if (smc)
841 		smc_fback_forward_wakeup(smc, clcsk,
842 					 smc->clcsk_data_ready);
843 	read_unlock_bh(&clcsk->sk_callback_lock);
844 }
845 
846 static void smc_fback_write_space(struct sock *clcsk)
847 {
848 	struct smc_sock *smc;
849 
850 	read_lock_bh(&clcsk->sk_callback_lock);
851 	smc = smc_clcsock_user_data(clcsk);
852 	if (smc)
853 		smc_fback_forward_wakeup(smc, clcsk,
854 					 smc->clcsk_write_space);
855 	read_unlock_bh(&clcsk->sk_callback_lock);
856 }
857 
858 static void smc_fback_error_report(struct sock *clcsk)
859 {
860 	struct smc_sock *smc;
861 
862 	read_lock_bh(&clcsk->sk_callback_lock);
863 	smc = smc_clcsock_user_data(clcsk);
864 	if (smc)
865 		smc_fback_forward_wakeup(smc, clcsk,
866 					 smc->clcsk_error_report);
867 	read_unlock_bh(&clcsk->sk_callback_lock);
868 }
869 
870 static void smc_fback_replace_callbacks(struct smc_sock *smc)
871 {
872 	struct sock *clcsk = smc->clcsock->sk;
873 
874 	write_lock_bh(&clcsk->sk_callback_lock);
875 	clcsk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
876 
877 	smc_clcsock_replace_cb(&clcsk->sk_state_change, smc_fback_state_change,
878 			       &smc->clcsk_state_change);
879 	smc_clcsock_replace_cb(&clcsk->sk_data_ready, smc_fback_data_ready,
880 			       &smc->clcsk_data_ready);
881 	smc_clcsock_replace_cb(&clcsk->sk_write_space, smc_fback_write_space,
882 			       &smc->clcsk_write_space);
883 	smc_clcsock_replace_cb(&clcsk->sk_error_report, smc_fback_error_report,
884 			       &smc->clcsk_error_report);
885 
886 	write_unlock_bh(&clcsk->sk_callback_lock);
887 }
888 
889 static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code)
890 {
891 	int rc = 0;
892 
893 	mutex_lock(&smc->clcsock_release_lock);
894 	if (!smc->clcsock) {
895 		rc = -EBADF;
896 		goto out;
897 	}
898 
899 	smc->use_fallback = true;
900 	smc->fallback_rsn = reason_code;
901 	smc_stat_fallback(smc);
902 	trace_smc_switch_to_fallback(smc, reason_code);
903 	if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
904 		smc->clcsock->file = smc->sk.sk_socket->file;
905 		smc->clcsock->file->private_data = smc->clcsock;
906 		smc->clcsock->wq.fasync_list =
907 			smc->sk.sk_socket->wq.fasync_list;
908 		smc->sk.sk_socket->wq.fasync_list = NULL;
909 
910 		/* There might be some wait entries remaining
911 		 * in smc sk->sk_wq and they should be woken up
912 		 * as clcsock's wait queue is woken up.
913 		 */
914 		smc_fback_replace_callbacks(smc);
915 	}
916 out:
917 	mutex_unlock(&smc->clcsock_release_lock);
918 	return rc;
919 }
920 
921 /* fall back during connect */
922 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
923 {
924 	struct net *net = sock_net(&smc->sk);
925 	int rc = 0;
926 
927 	rc = smc_switch_to_fallback(smc, reason_code);
928 	if (rc) { /* fallback fails */
929 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
930 		if (smc->sk.sk_state == SMC_INIT)
931 			sock_put(&smc->sk); /* passive closing */
932 		return rc;
933 	}
934 	smc_copy_sock_settings_to_clc(smc);
935 	smc->connect_nonblock = 0;
936 	if (smc->sk.sk_state == SMC_INIT)
937 		smc->sk.sk_state = SMC_ACTIVE;
938 	return 0;
939 }
940 
941 /* decline and fall back during connect */
942 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
943 					u8 version)
944 {
945 	struct net *net = sock_net(&smc->sk);
946 	int rc;
947 
948 	if (reason_code < 0) { /* error, fallback is not possible */
949 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
950 		if (smc->sk.sk_state == SMC_INIT)
951 			sock_put(&smc->sk); /* passive closing */
952 		return reason_code;
953 	}
954 	if (reason_code != SMC_CLC_DECL_PEERDECL) {
955 		rc = smc_clc_send_decline(smc, reason_code, version);
956 		if (rc < 0) {
957 			this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
958 			if (smc->sk.sk_state == SMC_INIT)
959 				sock_put(&smc->sk); /* passive closing */
960 			return rc;
961 		}
962 	}
963 	return smc_connect_fallback(smc, reason_code);
964 }
965 
966 static void smc_conn_abort(struct smc_sock *smc, int local_first)
967 {
968 	struct smc_connection *conn = &smc->conn;
969 	struct smc_link_group *lgr = conn->lgr;
970 	bool lgr_valid = false;
971 
972 	if (smc_conn_lgr_valid(conn))
973 		lgr_valid = true;
974 
975 	smc_conn_free(conn);
976 	if (local_first && lgr_valid)
977 		smc_lgr_cleanup_early(lgr);
978 }
979 
980 /* check if there is a rdma device available for this connection. */
981 /* called for connect and listen */
982 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
983 {
984 	/* PNET table look up: search active ib_device and port
985 	 * within same PNETID that also contains the ethernet device
986 	 * used for the internal TCP socket
987 	 */
988 	smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
989 	if (!ini->check_smcrv2 && !ini->ib_dev)
990 		return SMC_CLC_DECL_NOSMCRDEV;
991 	if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
992 		return SMC_CLC_DECL_NOSMCRDEV;
993 	return 0;
994 }
995 
996 /* check if there is an ISM device available for this connection. */
997 /* called for connect and listen */
998 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
999 {
1000 	/* Find ISM device with same PNETID as connecting interface  */
1001 	smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
1002 	if (!ini->ism_dev[0])
1003 		return SMC_CLC_DECL_NOSMCDDEV;
1004 	else
1005 		ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
1006 	return 0;
1007 }
1008 
1009 /* is chid unique for the ism devices that are already determined? */
1010 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
1011 					   int cnt)
1012 {
1013 	int i = (!ini->ism_dev[0]) ? 1 : 0;
1014 
1015 	for (; i < cnt; i++)
1016 		if (ini->ism_chid[i] == chid)
1017 			return false;
1018 	return true;
1019 }
1020 
1021 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
1022  * PNETID matching net_device)
1023  */
1024 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
1025 				       struct smc_init_info *ini)
1026 {
1027 	int rc = SMC_CLC_DECL_NOSMCDDEV;
1028 	struct smcd_dev *smcd;
1029 	int i = 1, entry = 1;
1030 	bool is_emulated;
1031 	u16 chid;
1032 
1033 	if (smcd_indicated(ini->smc_type_v1))
1034 		rc = 0;		/* already initialized for V1 */
1035 	mutex_lock(&smcd_dev_list.mutex);
1036 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1037 		if (smcd->going_away || smcd == ini->ism_dev[0])
1038 			continue;
1039 		chid = smc_ism_get_chid(smcd);
1040 		if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
1041 			continue;
1042 		is_emulated = __smc_ism_is_emulated(chid);
1043 		if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
1044 		    smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
1045 			if (is_emulated && entry == SMCD_CLC_MAX_V2_GID_ENTRIES)
1046 				/* It's the last GID-CHID entry left in CLC
1047 				 * Proposal SMC-Dv2 extension, but an Emulated-
1048 				 * ISM device will take two entries. So give
1049 				 * up it and try the next potential ISM device.
1050 				 */
1051 				continue;
1052 			ini->ism_dev[i] = smcd;
1053 			ini->ism_chid[i] = chid;
1054 			ini->is_smcd = true;
1055 			rc = 0;
1056 			i++;
1057 			entry = is_emulated ? entry + 2 : entry + 1;
1058 			if (entry > SMCD_CLC_MAX_V2_GID_ENTRIES)
1059 				break;
1060 		}
1061 	}
1062 	mutex_unlock(&smcd_dev_list.mutex);
1063 	ini->ism_offered_cnt = i - 1;
1064 	if (!ini->ism_dev[0] && !ini->ism_dev[1])
1065 		ini->smcd_version = 0;
1066 
1067 	return rc;
1068 }
1069 
1070 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
1071 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
1072 				      struct smc_init_info *ini)
1073 {
1074 	if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
1075 		return SMC_CLC_DECL_ISMVLANERR;
1076 	return 0;
1077 }
1078 
1079 static int smc_find_proposal_devices(struct smc_sock *smc,
1080 				     struct smc_init_info *ini)
1081 {
1082 	int rc = 0;
1083 
1084 	/* check if there is an ism device available */
1085 	if (!(ini->smcd_version & SMC_V1) ||
1086 	    smc_find_ism_device(smc, ini) ||
1087 	    smc_connect_ism_vlan_setup(smc, ini))
1088 		ini->smcd_version &= ~SMC_V1;
1089 	/* else ISM V1 is supported for this connection */
1090 
1091 	/* check if there is an rdma device available */
1092 	if (!(ini->smcr_version & SMC_V1) ||
1093 	    smc_find_rdma_device(smc, ini))
1094 		ini->smcr_version &= ~SMC_V1;
1095 	/* else RDMA is supported for this connection */
1096 
1097 	ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
1098 					      ini->smcr_version & SMC_V1);
1099 
1100 	/* check if there is an ism v2 device available */
1101 	if (!(ini->smcd_version & SMC_V2) ||
1102 	    !smc_ism_is_v2_capable() ||
1103 	    smc_find_ism_v2_device_clnt(smc, ini))
1104 		ini->smcd_version &= ~SMC_V2;
1105 
1106 	/* check if there is an rdma v2 device available */
1107 	ini->check_smcrv2 = true;
1108 	ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
1109 	if (!(ini->smcr_version & SMC_V2) ||
1110 	    smc->clcsock->sk->sk_family != AF_INET ||
1111 	    !smc_clc_ueid_count() ||
1112 	    smc_find_rdma_device(smc, ini))
1113 		ini->smcr_version &= ~SMC_V2;
1114 	ini->check_smcrv2 = false;
1115 
1116 	ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
1117 					      ini->smcr_version & SMC_V2);
1118 
1119 	/* if neither ISM nor RDMA are supported, fallback */
1120 	if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
1121 		rc = SMC_CLC_DECL_NOSMCDEV;
1122 
1123 	return rc;
1124 }
1125 
1126 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
1127  * used, the VLAN ID will be registered again during the connection setup.
1128  */
1129 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
1130 					struct smc_init_info *ini)
1131 {
1132 	if (!smcd_indicated(ini->smc_type_v1))
1133 		return 0;
1134 	if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
1135 		return SMC_CLC_DECL_CNFERR;
1136 	return 0;
1137 }
1138 
1139 #define SMC_CLC_MAX_ACCEPT_LEN \
1140 	(sizeof(struct smc_clc_msg_accept_confirm) + \
1141 	 sizeof(struct smc_clc_first_contact_ext_v2x) + \
1142 	 sizeof(struct smc_clc_msg_trail))
1143 
1144 /* CLC handshake during connect */
1145 static int smc_connect_clc(struct smc_sock *smc,
1146 			   struct smc_clc_msg_accept_confirm *aclc,
1147 			   struct smc_init_info *ini)
1148 {
1149 	int rc = 0;
1150 
1151 	/* do inband token exchange */
1152 	rc = smc_clc_send_proposal(smc, ini);
1153 	if (rc)
1154 		return rc;
1155 	/* receive SMC Accept CLC message */
1156 	return smc_clc_wait_msg(smc, aclc, SMC_CLC_MAX_ACCEPT_LEN,
1157 				SMC_CLC_ACCEPT, CLC_WAIT_TIME);
1158 }
1159 
1160 void smc_fill_gid_list(struct smc_link_group *lgr,
1161 		       struct smc_gidlist *gidlist,
1162 		       struct smc_ib_device *known_dev, u8 *known_gid)
1163 {
1164 	struct smc_init_info *alt_ini = NULL;
1165 
1166 	memset(gidlist, 0, sizeof(*gidlist));
1167 	memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
1168 
1169 	alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
1170 	if (!alt_ini)
1171 		goto out;
1172 
1173 	alt_ini->vlan_id = lgr->vlan_id;
1174 	alt_ini->check_smcrv2 = true;
1175 	alt_ini->smcrv2.saddr = lgr->saddr;
1176 	smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
1177 
1178 	if (!alt_ini->smcrv2.ib_dev_v2)
1179 		goto out;
1180 
1181 	memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
1182 	       SMC_GID_SIZE);
1183 
1184 out:
1185 	kfree(alt_ini);
1186 }
1187 
1188 static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
1189 				       struct smc_clc_msg_accept_confirm *aclc,
1190 				       struct smc_init_info *ini)
1191 {
1192 	struct smc_clc_first_contact_ext *fce =
1193 		smc_get_clc_first_contact_ext(aclc, false);
1194 	struct net *net = sock_net(&smc->sk);
1195 	int rc;
1196 
1197 	if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1198 		return 0;
1199 
1200 	if (fce->v2_direct) {
1201 		memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1202 		ini->smcrv2.uses_gateway = false;
1203 	} else {
1204 		if (smc_ib_find_route(net, smc->clcsock->sk->sk_rcv_saddr,
1205 				      smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1206 				      ini->smcrv2.nexthop_mac,
1207 				      &ini->smcrv2.uses_gateway))
1208 			return SMC_CLC_DECL_NOROUTE;
1209 		if (!ini->smcrv2.uses_gateway) {
1210 			/* mismatch: peer claims indirect, but its direct */
1211 			return SMC_CLC_DECL_NOINDIRECT;
1212 		}
1213 	}
1214 
1215 	ini->release_nr = fce->release;
1216 	rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1217 	if (rc)
1218 		return rc;
1219 
1220 	return 0;
1221 }
1222 
1223 /* setup for RDMA connection of client */
1224 static int smc_connect_rdma(struct smc_sock *smc,
1225 			    struct smc_clc_msg_accept_confirm *aclc,
1226 			    struct smc_init_info *ini)
1227 {
1228 	int i, reason_code = 0;
1229 	struct smc_link *link;
1230 	u8 *eid = NULL;
1231 
1232 	ini->is_smcd = false;
1233 	ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1234 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1235 	memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1236 	memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1237 	memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1238 	ini->max_conns = SMC_CONN_PER_LGR_MAX;
1239 	ini->max_links = SMC_LINKS_ADD_LNK_MAX;
1240 
1241 	reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1242 	if (reason_code)
1243 		return reason_code;
1244 
1245 	mutex_lock(&smc_client_lgr_pending);
1246 	reason_code = smc_conn_create(smc, ini);
1247 	if (reason_code) {
1248 		mutex_unlock(&smc_client_lgr_pending);
1249 		return reason_code;
1250 	}
1251 
1252 	smc_conn_save_peer_info(smc, aclc);
1253 
1254 	if (ini->first_contact_local) {
1255 		link = smc->conn.lnk;
1256 	} else {
1257 		/* set link that was assigned by server */
1258 		link = NULL;
1259 		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1260 			struct smc_link *l = &smc->conn.lgr->lnk[i];
1261 
1262 			if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1263 			    !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1264 				    SMC_GID_SIZE) &&
1265 			    (aclc->hdr.version > SMC_V1 ||
1266 			     !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1267 				     sizeof(l->peer_mac)))) {
1268 				link = l;
1269 				break;
1270 			}
1271 		}
1272 		if (!link) {
1273 			reason_code = SMC_CLC_DECL_NOSRVLINK;
1274 			goto connect_abort;
1275 		}
1276 		smc_switch_link_and_count(&smc->conn, link);
1277 	}
1278 
1279 	/* create send buffer and rmb */
1280 	if (smc_buf_create(smc, false)) {
1281 		reason_code = SMC_CLC_DECL_MEM;
1282 		goto connect_abort;
1283 	}
1284 
1285 	if (ini->first_contact_local)
1286 		smc_link_save_peer_info(link, aclc, ini);
1287 
1288 	if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1289 		reason_code = SMC_CLC_DECL_ERR_RTOK;
1290 		goto connect_abort;
1291 	}
1292 
1293 	smc_close_init(smc);
1294 	smc_rx_init(smc);
1295 
1296 	if (ini->first_contact_local) {
1297 		if (smc_ib_ready_link(link)) {
1298 			reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1299 			goto connect_abort;
1300 		}
1301 	} else {
1302 		/* reg sendbufs if they were vzalloced */
1303 		if (smc->conn.sndbuf_desc->is_vm) {
1304 			if (smcr_lgr_reg_sndbufs(link, smc->conn.sndbuf_desc)) {
1305 				reason_code = SMC_CLC_DECL_ERR_REGBUF;
1306 				goto connect_abort;
1307 			}
1308 		}
1309 		if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1310 			reason_code = SMC_CLC_DECL_ERR_REGBUF;
1311 			goto connect_abort;
1312 		}
1313 	}
1314 
1315 	if (aclc->hdr.version > SMC_V1) {
1316 		eid = aclc->r1.eid;
1317 		if (ini->first_contact_local)
1318 			smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1319 					  link->smcibdev, link->gid);
1320 	}
1321 
1322 	reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1323 					   aclc->hdr.version, eid, ini);
1324 	if (reason_code)
1325 		goto connect_abort;
1326 
1327 	smc_tx_init(smc);
1328 
1329 	if (ini->first_contact_local) {
1330 		/* QP confirmation over RoCE fabric */
1331 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1332 		reason_code = smcr_clnt_conf_first_link(smc);
1333 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1334 		if (reason_code)
1335 			goto connect_abort;
1336 	}
1337 	mutex_unlock(&smc_client_lgr_pending);
1338 
1339 	smc_copy_sock_settings_to_clc(smc);
1340 	smc->connect_nonblock = 0;
1341 	if (smc->sk.sk_state == SMC_INIT)
1342 		smc->sk.sk_state = SMC_ACTIVE;
1343 
1344 	return 0;
1345 connect_abort:
1346 	smc_conn_abort(smc, ini->first_contact_local);
1347 	mutex_unlock(&smc_client_lgr_pending);
1348 	smc->connect_nonblock = 0;
1349 
1350 	return reason_code;
1351 }
1352 
1353 /* The server has chosen one of the proposed ISM devices for the communication.
1354  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1355  */
1356 static int
1357 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm *aclc,
1358 			       struct smc_init_info *ini)
1359 {
1360 	int i;
1361 
1362 	for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1363 		if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1364 			ini->ism_selected = i;
1365 			return 0;
1366 		}
1367 	}
1368 
1369 	return -EPROTO;
1370 }
1371 
1372 /* setup for ISM connection of client */
1373 static int smc_connect_ism(struct smc_sock *smc,
1374 			   struct smc_clc_msg_accept_confirm *aclc,
1375 			   struct smc_init_info *ini)
1376 {
1377 	u8 *eid = NULL;
1378 	int rc = 0;
1379 
1380 	ini->is_smcd = true;
1381 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1382 
1383 	if (aclc->hdr.version == SMC_V2) {
1384 		if (ini->first_contact_peer) {
1385 			struct smc_clc_first_contact_ext *fce =
1386 				smc_get_clc_first_contact_ext(aclc, true);
1387 
1388 			ini->release_nr = fce->release;
1389 			rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1390 			if (rc)
1391 				return rc;
1392 		}
1393 
1394 		rc = smc_v2_determine_accepted_chid(aclc, ini);
1395 		if (rc)
1396 			return rc;
1397 
1398 		if (__smc_ism_is_emulated(ini->ism_chid[ini->ism_selected]))
1399 			ini->ism_peer_gid[ini->ism_selected].gid_ext =
1400 						ntohll(aclc->d1.gid_ext);
1401 		/* for non-Emulated-ISM devices, peer gid_ext remains 0. */
1402 	}
1403 	ini->ism_peer_gid[ini->ism_selected].gid = ntohll(aclc->d0.gid);
1404 
1405 	/* there is only one lgr role for SMC-D; use server lock */
1406 	mutex_lock(&smc_server_lgr_pending);
1407 	rc = smc_conn_create(smc, ini);
1408 	if (rc) {
1409 		mutex_unlock(&smc_server_lgr_pending);
1410 		return rc;
1411 	}
1412 
1413 	/* Create send and receive buffers */
1414 	rc = smc_buf_create(smc, true);
1415 	if (rc) {
1416 		rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1417 		goto connect_abort;
1418 	}
1419 
1420 	smc_conn_save_peer_info(smc, aclc);
1421 
1422 	if (smc_ism_support_dmb_nocopy(smc->conn.lgr->smcd)) {
1423 		rc = smcd_buf_attach(smc);
1424 		if (rc) {
1425 			rc = SMC_CLC_DECL_MEM;	/* try to fallback */
1426 			goto connect_abort;
1427 		}
1428 	}
1429 	smc_close_init(smc);
1430 	smc_rx_init(smc);
1431 	smc_tx_init(smc);
1432 
1433 	if (aclc->hdr.version > SMC_V1)
1434 		eid = aclc->d1.eid;
1435 
1436 	rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1437 				  aclc->hdr.version, eid, ini);
1438 	if (rc)
1439 		goto connect_abort;
1440 	mutex_unlock(&smc_server_lgr_pending);
1441 
1442 	smc_copy_sock_settings_to_clc(smc);
1443 	smc->connect_nonblock = 0;
1444 	if (smc->sk.sk_state == SMC_INIT)
1445 		smc->sk.sk_state = SMC_ACTIVE;
1446 
1447 	return 0;
1448 connect_abort:
1449 	smc_conn_abort(smc, ini->first_contact_local);
1450 	mutex_unlock(&smc_server_lgr_pending);
1451 	smc->connect_nonblock = 0;
1452 
1453 	return rc;
1454 }
1455 
1456 /* check if received accept type and version matches a proposed one */
1457 static int smc_connect_check_aclc(struct smc_init_info *ini,
1458 				  struct smc_clc_msg_accept_confirm *aclc)
1459 {
1460 	if (aclc->hdr.typev1 != SMC_TYPE_R &&
1461 	    aclc->hdr.typev1 != SMC_TYPE_D)
1462 		return SMC_CLC_DECL_MODEUNSUPP;
1463 
1464 	if (aclc->hdr.version >= SMC_V2) {
1465 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1466 		     !smcr_indicated(ini->smc_type_v2)) ||
1467 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1468 		     !smcd_indicated(ini->smc_type_v2)))
1469 			return SMC_CLC_DECL_MODEUNSUPP;
1470 	} else {
1471 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1472 		     !smcr_indicated(ini->smc_type_v1)) ||
1473 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1474 		     !smcd_indicated(ini->smc_type_v1)))
1475 			return SMC_CLC_DECL_MODEUNSUPP;
1476 	}
1477 
1478 	return 0;
1479 }
1480 
1481 /* perform steps before actually connecting */
1482 static int __smc_connect(struct smc_sock *smc)
1483 {
1484 	u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1485 	struct smc_clc_msg_accept_confirm *aclc;
1486 	struct smc_init_info *ini = NULL;
1487 	u8 *buf = NULL;
1488 	int rc = 0;
1489 
1490 	if (smc->use_fallback)
1491 		return smc_connect_fallback(smc, smc->fallback_rsn);
1492 
1493 	/* if peer has not signalled SMC-capability, fall back */
1494 	if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1495 		return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1496 
1497 	/* IPSec connections opt out of SMC optimizations */
1498 	if (using_ipsec(smc))
1499 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1500 						    version);
1501 
1502 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1503 	if (!ini)
1504 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1505 						    version);
1506 
1507 	ini->smcd_version = SMC_V1 | SMC_V2;
1508 	ini->smcr_version = SMC_V1 | SMC_V2;
1509 	ini->smc_type_v1 = SMC_TYPE_B;
1510 	ini->smc_type_v2 = SMC_TYPE_B;
1511 
1512 	/* get vlan id from IP device */
1513 	if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1514 		ini->smcd_version &= ~SMC_V1;
1515 		ini->smcr_version = 0;
1516 		ini->smc_type_v1 = SMC_TYPE_N;
1517 		if (!ini->smcd_version) {
1518 			rc = SMC_CLC_DECL_GETVLANERR;
1519 			goto fallback;
1520 		}
1521 	}
1522 
1523 	rc = smc_find_proposal_devices(smc, ini);
1524 	if (rc)
1525 		goto fallback;
1526 
1527 	buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1528 	if (!buf) {
1529 		rc = SMC_CLC_DECL_MEM;
1530 		goto fallback;
1531 	}
1532 	aclc = (struct smc_clc_msg_accept_confirm *)buf;
1533 
1534 	/* perform CLC handshake */
1535 	rc = smc_connect_clc(smc, aclc, ini);
1536 	if (rc) {
1537 		/* -EAGAIN on timeout, see tcp_recvmsg() */
1538 		if (rc == -EAGAIN) {
1539 			rc = -ETIMEDOUT;
1540 			smc->sk.sk_err = ETIMEDOUT;
1541 		}
1542 		goto vlan_cleanup;
1543 	}
1544 
1545 	/* check if smc modes and versions of CLC proposal and accept match */
1546 	rc = smc_connect_check_aclc(ini, aclc);
1547 	version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1548 	if (rc)
1549 		goto vlan_cleanup;
1550 
1551 	/* depending on previous steps, connect using rdma or ism */
1552 	if (aclc->hdr.typev1 == SMC_TYPE_R) {
1553 		ini->smcr_version = version;
1554 		rc = smc_connect_rdma(smc, aclc, ini);
1555 	} else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1556 		ini->smcd_version = version;
1557 		rc = smc_connect_ism(smc, aclc, ini);
1558 	}
1559 	if (rc)
1560 		goto vlan_cleanup;
1561 
1562 	SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1563 	smc_connect_ism_vlan_cleanup(smc, ini);
1564 	kfree(buf);
1565 	kfree(ini);
1566 	return 0;
1567 
1568 vlan_cleanup:
1569 	smc_connect_ism_vlan_cleanup(smc, ini);
1570 	kfree(buf);
1571 fallback:
1572 	kfree(ini);
1573 	return smc_connect_decline_fallback(smc, rc, version);
1574 }
1575 
1576 static void smc_connect_work(struct work_struct *work)
1577 {
1578 	struct smc_sock *smc = container_of(work, struct smc_sock,
1579 					    connect_work);
1580 	long timeo = smc->sk.sk_sndtimeo;
1581 	int rc = 0;
1582 
1583 	if (!timeo)
1584 		timeo = MAX_SCHEDULE_TIMEOUT;
1585 	lock_sock(smc->clcsock->sk);
1586 	if (smc->clcsock->sk->sk_err) {
1587 		smc->sk.sk_err = smc->clcsock->sk->sk_err;
1588 	} else if ((1 << smc->clcsock->sk->sk_state) &
1589 					(TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1590 		rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1591 		if ((rc == -EPIPE) &&
1592 		    ((1 << smc->clcsock->sk->sk_state) &
1593 					(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1594 			rc = 0;
1595 	}
1596 	release_sock(smc->clcsock->sk);
1597 	lock_sock(&smc->sk);
1598 	if (rc != 0 || smc->sk.sk_err) {
1599 		smc->sk.sk_state = SMC_CLOSED;
1600 		if (rc == -EPIPE || rc == -EAGAIN)
1601 			smc->sk.sk_err = EPIPE;
1602 		else if (rc == -ECONNREFUSED)
1603 			smc->sk.sk_err = ECONNREFUSED;
1604 		else if (signal_pending(current))
1605 			smc->sk.sk_err = -sock_intr_errno(timeo);
1606 		sock_put(&smc->sk); /* passive closing */
1607 		goto out;
1608 	}
1609 
1610 	rc = __smc_connect(smc);
1611 	if (rc < 0)
1612 		smc->sk.sk_err = -rc;
1613 
1614 out:
1615 	if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1616 		if (smc->sk.sk_err) {
1617 			smc->sk.sk_state_change(&smc->sk);
1618 		} else { /* allow polling before and after fallback decision */
1619 			smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1620 			smc->sk.sk_write_space(&smc->sk);
1621 		}
1622 	}
1623 	release_sock(&smc->sk);
1624 }
1625 
1626 static int smc_connect(struct socket *sock, struct sockaddr *addr,
1627 		       int alen, int flags)
1628 {
1629 	struct sock *sk = sock->sk;
1630 	struct smc_sock *smc;
1631 	int rc = -EINVAL;
1632 
1633 	smc = smc_sk(sk);
1634 
1635 	/* separate smc parameter checking to be safe */
1636 	if (alen < sizeof(addr->sa_family))
1637 		goto out_err;
1638 	if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1639 		goto out_err;
1640 
1641 	lock_sock(sk);
1642 	switch (sock->state) {
1643 	default:
1644 		rc = -EINVAL;
1645 		goto out;
1646 	case SS_CONNECTED:
1647 		rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1648 		goto out;
1649 	case SS_CONNECTING:
1650 		if (sk->sk_state == SMC_ACTIVE)
1651 			goto connected;
1652 		break;
1653 	case SS_UNCONNECTED:
1654 		sock->state = SS_CONNECTING;
1655 		break;
1656 	}
1657 
1658 	switch (sk->sk_state) {
1659 	default:
1660 		goto out;
1661 	case SMC_CLOSED:
1662 		rc = sock_error(sk) ? : -ECONNABORTED;
1663 		sock->state = SS_UNCONNECTED;
1664 		goto out;
1665 	case SMC_ACTIVE:
1666 		rc = -EISCONN;
1667 		goto out;
1668 	case SMC_INIT:
1669 		break;
1670 	}
1671 
1672 	smc_copy_sock_settings_to_clc(smc);
1673 	tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1674 	if (smc->connect_nonblock) {
1675 		rc = -EALREADY;
1676 		goto out;
1677 	}
1678 	rc = kernel_connect(smc->clcsock, addr, alen, flags);
1679 	if (rc && rc != -EINPROGRESS)
1680 		goto out;
1681 
1682 	if (smc->use_fallback) {
1683 		sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1684 		goto out;
1685 	}
1686 	sock_hold(&smc->sk); /* sock put in passive closing */
1687 	if (flags & O_NONBLOCK) {
1688 		if (queue_work(smc_hs_wq, &smc->connect_work))
1689 			smc->connect_nonblock = 1;
1690 		rc = -EINPROGRESS;
1691 		goto out;
1692 	} else {
1693 		rc = __smc_connect(smc);
1694 		if (rc < 0)
1695 			goto out;
1696 	}
1697 
1698 connected:
1699 	rc = 0;
1700 	sock->state = SS_CONNECTED;
1701 out:
1702 	release_sock(sk);
1703 out_err:
1704 	return rc;
1705 }
1706 
1707 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1708 {
1709 	struct socket *new_clcsock = NULL;
1710 	struct sock *lsk = &lsmc->sk;
1711 	struct sock *new_sk;
1712 	int rc = -EINVAL;
1713 
1714 	release_sock(lsk);
1715 	new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1716 	if (!new_sk) {
1717 		rc = -ENOMEM;
1718 		lsk->sk_err = ENOMEM;
1719 		*new_smc = NULL;
1720 		lock_sock(lsk);
1721 		goto out;
1722 	}
1723 	*new_smc = smc_sk(new_sk);
1724 
1725 	mutex_lock(&lsmc->clcsock_release_lock);
1726 	if (lsmc->clcsock)
1727 		rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1728 	mutex_unlock(&lsmc->clcsock_release_lock);
1729 	lock_sock(lsk);
1730 	if  (rc < 0 && rc != -EAGAIN)
1731 		lsk->sk_err = -rc;
1732 	if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1733 		new_sk->sk_prot->unhash(new_sk);
1734 		if (new_clcsock)
1735 			sock_release(new_clcsock);
1736 		new_sk->sk_state = SMC_CLOSED;
1737 		smc_sock_set_flag(new_sk, SOCK_DEAD);
1738 		sock_put(new_sk); /* final */
1739 		*new_smc = NULL;
1740 		goto out;
1741 	}
1742 
1743 	/* new clcsock has inherited the smc listen-specific sk_data_ready
1744 	 * function; switch it back to the original sk_data_ready function
1745 	 */
1746 	new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1747 
1748 	/* if new clcsock has also inherited the fallback-specific callback
1749 	 * functions, switch them back to the original ones.
1750 	 */
1751 	if (lsmc->use_fallback) {
1752 		if (lsmc->clcsk_state_change)
1753 			new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1754 		if (lsmc->clcsk_write_space)
1755 			new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1756 		if (lsmc->clcsk_error_report)
1757 			new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1758 	}
1759 
1760 	(*new_smc)->clcsock = new_clcsock;
1761 out:
1762 	return rc;
1763 }
1764 
1765 /* add a just created sock to the accept queue of the listen sock as
1766  * candidate for a following socket accept call from user space
1767  */
1768 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1769 {
1770 	struct smc_sock *par = smc_sk(parent);
1771 
1772 	sock_hold(sk); /* sock_put in smc_accept_unlink () */
1773 	spin_lock(&par->accept_q_lock);
1774 	list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1775 	spin_unlock(&par->accept_q_lock);
1776 	sk_acceptq_added(parent);
1777 }
1778 
1779 /* remove a socket from the accept queue of its parental listening socket */
1780 static void smc_accept_unlink(struct sock *sk)
1781 {
1782 	struct smc_sock *par = smc_sk(sk)->listen_smc;
1783 
1784 	spin_lock(&par->accept_q_lock);
1785 	list_del_init(&smc_sk(sk)->accept_q);
1786 	spin_unlock(&par->accept_q_lock);
1787 	sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1788 	sock_put(sk); /* sock_hold in smc_accept_enqueue */
1789 }
1790 
1791 /* remove a sock from the accept queue to bind it to a new socket created
1792  * for a socket accept call from user space
1793  */
1794 struct sock *smc_accept_dequeue(struct sock *parent,
1795 				struct socket *new_sock)
1796 {
1797 	struct smc_sock *isk, *n;
1798 	struct sock *new_sk;
1799 
1800 	list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1801 		new_sk = (struct sock *)isk;
1802 
1803 		smc_accept_unlink(new_sk);
1804 		if (new_sk->sk_state == SMC_CLOSED) {
1805 			new_sk->sk_prot->unhash(new_sk);
1806 			if (isk->clcsock) {
1807 				sock_release(isk->clcsock);
1808 				isk->clcsock = NULL;
1809 			}
1810 			sock_put(new_sk); /* final */
1811 			continue;
1812 		}
1813 		if (new_sock) {
1814 			sock_graft(new_sk, new_sock);
1815 			new_sock->state = SS_CONNECTED;
1816 			if (isk->use_fallback) {
1817 				smc_sk(new_sk)->clcsock->file = new_sock->file;
1818 				isk->clcsock->file->private_data = isk->clcsock;
1819 			}
1820 		}
1821 		return new_sk;
1822 	}
1823 	return NULL;
1824 }
1825 
1826 /* clean up for a created but never accepted sock */
1827 void smc_close_non_accepted(struct sock *sk)
1828 {
1829 	struct smc_sock *smc = smc_sk(sk);
1830 
1831 	sock_hold(sk); /* sock_put below */
1832 	lock_sock(sk);
1833 	if (!sk->sk_lingertime)
1834 		/* wait for peer closing */
1835 		WRITE_ONCE(sk->sk_lingertime, SMC_MAX_STREAM_WAIT_TIMEOUT);
1836 	__smc_release(smc);
1837 	release_sock(sk);
1838 	sock_put(sk); /* sock_hold above */
1839 	sock_put(sk); /* final sock_put */
1840 }
1841 
1842 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1843 {
1844 	struct smc_link *link = smc->conn.lnk;
1845 	struct smc_llc_qentry *qentry;
1846 	int rc;
1847 
1848 	/* reg the sndbuf if it was vzalloced*/
1849 	if (smc->conn.sndbuf_desc->is_vm) {
1850 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
1851 			return SMC_CLC_DECL_ERR_REGBUF;
1852 	}
1853 
1854 	/* reg the rmb */
1855 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
1856 		return SMC_CLC_DECL_ERR_REGBUF;
1857 
1858 	/* send CONFIRM LINK request to client over the RoCE fabric */
1859 	rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1860 	if (rc < 0)
1861 		return SMC_CLC_DECL_TIMEOUT_CL;
1862 
1863 	/* receive CONFIRM LINK response from client over the RoCE fabric */
1864 	qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1865 			      SMC_LLC_CONFIRM_LINK);
1866 	if (!qentry) {
1867 		struct smc_clc_msg_decline dclc;
1868 
1869 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1870 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1871 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1872 	}
1873 	smc_llc_save_peer_uid(qentry);
1874 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1875 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1876 	if (rc)
1877 		return SMC_CLC_DECL_RMBE_EC;
1878 
1879 	/* confirm_rkey is implicit on 1st contact */
1880 	smc->conn.rmb_desc->is_conf_rkey = true;
1881 
1882 	smc_llc_link_active(link);
1883 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1884 
1885 	if (link->lgr->max_links > 1) {
1886 		down_write(&link->lgr->llc_conf_mutex);
1887 		/* initial contact - try to establish second link */
1888 		smc_llc_srv_add_link(link, NULL);
1889 		up_write(&link->lgr->llc_conf_mutex);
1890 	}
1891 	return 0;
1892 }
1893 
1894 /* listen worker: finish */
1895 static void smc_listen_out(struct smc_sock *new_smc)
1896 {
1897 	struct smc_sock *lsmc = new_smc->listen_smc;
1898 	struct sock *newsmcsk = &new_smc->sk;
1899 
1900 	if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1901 		atomic_dec(&lsmc->queued_smc_hs);
1902 
1903 	if (lsmc->sk.sk_state == SMC_LISTEN) {
1904 		lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1905 		smc_accept_enqueue(&lsmc->sk, newsmcsk);
1906 		release_sock(&lsmc->sk);
1907 	} else { /* no longer listening */
1908 		smc_close_non_accepted(newsmcsk);
1909 	}
1910 
1911 	/* Wake up accept */
1912 	lsmc->sk.sk_data_ready(&lsmc->sk);
1913 	sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1914 }
1915 
1916 /* listen worker: finish in state connected */
1917 static void smc_listen_out_connected(struct smc_sock *new_smc)
1918 {
1919 	struct sock *newsmcsk = &new_smc->sk;
1920 
1921 	if (newsmcsk->sk_state == SMC_INIT)
1922 		newsmcsk->sk_state = SMC_ACTIVE;
1923 
1924 	smc_listen_out(new_smc);
1925 }
1926 
1927 /* listen worker: finish in error state */
1928 static void smc_listen_out_err(struct smc_sock *new_smc)
1929 {
1930 	struct sock *newsmcsk = &new_smc->sk;
1931 	struct net *net = sock_net(newsmcsk);
1932 
1933 	this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1934 	if (newsmcsk->sk_state == SMC_INIT)
1935 		sock_put(&new_smc->sk); /* passive closing */
1936 	newsmcsk->sk_state = SMC_CLOSED;
1937 
1938 	smc_listen_out(new_smc);
1939 }
1940 
1941 /* listen worker: decline and fall back if possible */
1942 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1943 			       int local_first, u8 version)
1944 {
1945 	/* RDMA setup failed, switch back to TCP */
1946 	smc_conn_abort(new_smc, local_first);
1947 	if (reason_code < 0 ||
1948 	    smc_switch_to_fallback(new_smc, reason_code)) {
1949 		/* error, no fallback possible */
1950 		smc_listen_out_err(new_smc);
1951 		return;
1952 	}
1953 	if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1954 		if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1955 			smc_listen_out_err(new_smc);
1956 			return;
1957 		}
1958 	}
1959 	smc_listen_out_connected(new_smc);
1960 }
1961 
1962 /* listen worker: version checking */
1963 static int smc_listen_v2_check(struct smc_sock *new_smc,
1964 			       struct smc_clc_msg_proposal *pclc,
1965 			       struct smc_init_info *ini)
1966 {
1967 	struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1968 	struct smc_clc_v2_extension *pclc_v2_ext;
1969 	int rc = SMC_CLC_DECL_PEERNOSMC;
1970 
1971 	ini->smc_type_v1 = pclc->hdr.typev1;
1972 	ini->smc_type_v2 = pclc->hdr.typev2;
1973 	ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1974 	ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1975 	if (pclc->hdr.version > SMC_V1) {
1976 		if (smcd_indicated(ini->smc_type_v2))
1977 			ini->smcd_version |= SMC_V2;
1978 		if (smcr_indicated(ini->smc_type_v2))
1979 			ini->smcr_version |= SMC_V2;
1980 	}
1981 	if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1982 		rc = SMC_CLC_DECL_PEERNOSMC;
1983 		goto out;
1984 	}
1985 	pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1986 	if (!pclc_v2_ext) {
1987 		ini->smcd_version &= ~SMC_V2;
1988 		ini->smcr_version &= ~SMC_V2;
1989 		rc = SMC_CLC_DECL_NOV2EXT;
1990 		goto out;
1991 	}
1992 	pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
1993 	if (ini->smcd_version & SMC_V2) {
1994 		if (!smc_ism_is_v2_capable()) {
1995 			ini->smcd_version &= ~SMC_V2;
1996 			rc = SMC_CLC_DECL_NOISM2SUPP;
1997 		} else if (!pclc_smcd_v2_ext) {
1998 			ini->smcd_version &= ~SMC_V2;
1999 			rc = SMC_CLC_DECL_NOV2DEXT;
2000 		} else if (!pclc_v2_ext->hdr.eid_cnt &&
2001 			   !pclc_v2_ext->hdr.flag.seid) {
2002 			ini->smcd_version &= ~SMC_V2;
2003 			rc = SMC_CLC_DECL_NOUEID;
2004 		}
2005 	}
2006 	if (ini->smcr_version & SMC_V2) {
2007 		if (!pclc_v2_ext->hdr.eid_cnt) {
2008 			ini->smcr_version &= ~SMC_V2;
2009 			rc = SMC_CLC_DECL_NOUEID;
2010 		}
2011 	}
2012 
2013 	ini->release_nr = pclc_v2_ext->hdr.flag.release;
2014 	if (pclc_v2_ext->hdr.flag.release > SMC_RELEASE)
2015 		ini->release_nr = SMC_RELEASE;
2016 
2017 out:
2018 	if (!ini->smcd_version && !ini->smcr_version)
2019 		return rc;
2020 
2021 	return 0;
2022 }
2023 
2024 /* listen worker: check prefixes */
2025 static int smc_listen_prfx_check(struct smc_sock *new_smc,
2026 				 struct smc_clc_msg_proposal *pclc)
2027 {
2028 	struct smc_clc_msg_proposal_prefix *pclc_prfx;
2029 	struct socket *newclcsock = new_smc->clcsock;
2030 
2031 	if (pclc->hdr.typev1 == SMC_TYPE_N)
2032 		return 0;
2033 	pclc_prfx = smc_clc_proposal_get_prefix(pclc);
2034 	if (smc_clc_prfx_match(newclcsock, pclc_prfx))
2035 		return SMC_CLC_DECL_DIFFPREFIX;
2036 
2037 	return 0;
2038 }
2039 
2040 /* listen worker: initialize connection and buffers */
2041 static int smc_listen_rdma_init(struct smc_sock *new_smc,
2042 				struct smc_init_info *ini)
2043 {
2044 	int rc;
2045 
2046 	/* allocate connection / link group */
2047 	rc = smc_conn_create(new_smc, ini);
2048 	if (rc)
2049 		return rc;
2050 
2051 	/* create send buffer and rmb */
2052 	if (smc_buf_create(new_smc, false)) {
2053 		smc_conn_abort(new_smc, ini->first_contact_local);
2054 		return SMC_CLC_DECL_MEM;
2055 	}
2056 
2057 	return 0;
2058 }
2059 
2060 /* listen worker: initialize connection and buffers for SMC-D */
2061 static int smc_listen_ism_init(struct smc_sock *new_smc,
2062 			       struct smc_init_info *ini)
2063 {
2064 	int rc;
2065 
2066 	rc = smc_conn_create(new_smc, ini);
2067 	if (rc)
2068 		return rc;
2069 
2070 	/* Create send and receive buffers */
2071 	rc = smc_buf_create(new_smc, true);
2072 	if (rc) {
2073 		smc_conn_abort(new_smc, ini->first_contact_local);
2074 		return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2075 					 SMC_CLC_DECL_MEM;
2076 	}
2077 
2078 	return 0;
2079 }
2080 
2081 static bool smc_is_already_selected(struct smcd_dev *smcd,
2082 				    struct smc_init_info *ini,
2083 				    int matches)
2084 {
2085 	int i;
2086 
2087 	for (i = 0; i < matches; i++)
2088 		if (smcd == ini->ism_dev[i])
2089 			return true;
2090 
2091 	return false;
2092 }
2093 
2094 /* check for ISM devices matching proposed ISM devices */
2095 static void smc_check_ism_v2_match(struct smc_init_info *ini,
2096 				   u16 proposed_chid,
2097 				   struct smcd_gid *proposed_gid,
2098 				   unsigned int *matches)
2099 {
2100 	struct smcd_dev *smcd;
2101 
2102 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2103 		if (smcd->going_away)
2104 			continue;
2105 		if (smc_is_already_selected(smcd, ini, *matches))
2106 			continue;
2107 		if (smc_ism_get_chid(smcd) == proposed_chid &&
2108 		    !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2109 			ini->ism_peer_gid[*matches].gid = proposed_gid->gid;
2110 			if (__smc_ism_is_emulated(proposed_chid))
2111 				ini->ism_peer_gid[*matches].gid_ext =
2112 							proposed_gid->gid_ext;
2113 				/* non-Emulated-ISM's peer gid_ext remains 0. */
2114 			ini->ism_dev[*matches] = smcd;
2115 			(*matches)++;
2116 			break;
2117 		}
2118 	}
2119 }
2120 
2121 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2122 {
2123 	if (!ini->rc)
2124 		ini->rc = rc;
2125 }
2126 
2127 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2128 					struct smc_clc_msg_proposal *pclc,
2129 					struct smc_init_info *ini)
2130 {
2131 	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2132 	struct smc_clc_v2_extension *smc_v2_ext;
2133 	struct smc_clc_msg_smcd *pclc_smcd;
2134 	unsigned int matches = 0;
2135 	struct smcd_gid smcd_gid;
2136 	u8 smcd_version;
2137 	u8 *eid = NULL;
2138 	int i, rc;
2139 	u16 chid;
2140 
2141 	if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2142 		goto not_found;
2143 
2144 	pclc_smcd = smc_get_clc_msg_smcd(pclc);
2145 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2146 	smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2147 
2148 	mutex_lock(&smcd_dev_list.mutex);
2149 	if (pclc_smcd->ism.chid) {
2150 		/* check for ISM device matching proposed native ISM device */
2151 		smcd_gid.gid = ntohll(pclc_smcd->ism.gid);
2152 		smcd_gid.gid_ext = 0;
2153 		smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2154 				       &smcd_gid, &matches);
2155 	}
2156 	for (i = 0; i < smc_v2_ext->hdr.ism_gid_cnt; i++) {
2157 		/* check for ISM devices matching proposed non-native ISM
2158 		 * devices
2159 		 */
2160 		smcd_gid.gid = ntohll(smcd_v2_ext->gidchid[i].gid);
2161 		smcd_gid.gid_ext = 0;
2162 		chid = ntohs(smcd_v2_ext->gidchid[i].chid);
2163 		if (__smc_ism_is_emulated(chid)) {
2164 			if ((i + 1) == smc_v2_ext->hdr.ism_gid_cnt ||
2165 			    chid != ntohs(smcd_v2_ext->gidchid[i + 1].chid))
2166 				/* each Emulated-ISM device takes two GID-CHID
2167 				 * entries and CHID of the second entry repeats
2168 				 * that of the first entry.
2169 				 *
2170 				 * So check if the next GID-CHID entry exists
2171 				 * and both two entries' CHIDs are the same.
2172 				 */
2173 				continue;
2174 			smcd_gid.gid_ext =
2175 				ntohll(smcd_v2_ext->gidchid[++i].gid);
2176 		}
2177 		smc_check_ism_v2_match(ini, chid, &smcd_gid, &matches);
2178 	}
2179 	mutex_unlock(&smcd_dev_list.mutex);
2180 
2181 	if (!ini->ism_dev[0]) {
2182 		smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2183 		goto not_found;
2184 	}
2185 
2186 	smc_ism_get_system_eid(&eid);
2187 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2188 			       smcd_v2_ext->system_eid, eid))
2189 		goto not_found;
2190 
2191 	/* separate - outside the smcd_dev_list.lock */
2192 	smcd_version = ini->smcd_version;
2193 	for (i = 0; i < matches; i++) {
2194 		ini->smcd_version = SMC_V2;
2195 		ini->is_smcd = true;
2196 		ini->ism_selected = i;
2197 		rc = smc_listen_ism_init(new_smc, ini);
2198 		if (rc) {
2199 			smc_find_ism_store_rc(rc, ini);
2200 			/* try next active ISM device */
2201 			continue;
2202 		}
2203 		return; /* matching and usable V2 ISM device found */
2204 	}
2205 	/* no V2 ISM device could be initialized */
2206 	ini->smcd_version = smcd_version;	/* restore original value */
2207 	ini->negotiated_eid[0] = 0;
2208 
2209 not_found:
2210 	ini->smcd_version &= ~SMC_V2;
2211 	ini->ism_dev[0] = NULL;
2212 	ini->is_smcd = false;
2213 }
2214 
2215 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2216 					struct smc_clc_msg_proposal *pclc,
2217 					struct smc_init_info *ini)
2218 {
2219 	struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2220 	int rc = 0;
2221 
2222 	/* check if ISM V1 is available */
2223 	if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2224 		goto not_found;
2225 	ini->is_smcd = true; /* prepare ISM check */
2226 	ini->ism_peer_gid[0].gid = ntohll(pclc_smcd->ism.gid);
2227 	ini->ism_peer_gid[0].gid_ext = 0;
2228 	rc = smc_find_ism_device(new_smc, ini);
2229 	if (rc)
2230 		goto not_found;
2231 	ini->ism_selected = 0;
2232 	rc = smc_listen_ism_init(new_smc, ini);
2233 	if (!rc)
2234 		return;		/* V1 ISM device found */
2235 
2236 not_found:
2237 	smc_find_ism_store_rc(rc, ini);
2238 	ini->smcd_version &= ~SMC_V1;
2239 	ini->ism_dev[0] = NULL;
2240 	ini->is_smcd = false;
2241 }
2242 
2243 /* listen worker: register buffers */
2244 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2245 {
2246 	struct smc_connection *conn = &new_smc->conn;
2247 
2248 	if (!local_first) {
2249 		/* reg sendbufs if they were vzalloced */
2250 		if (conn->sndbuf_desc->is_vm) {
2251 			if (smcr_lgr_reg_sndbufs(conn->lnk,
2252 						 conn->sndbuf_desc))
2253 				return SMC_CLC_DECL_ERR_REGBUF;
2254 		}
2255 		if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2256 			return SMC_CLC_DECL_ERR_REGBUF;
2257 	}
2258 
2259 	return 0;
2260 }
2261 
2262 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2263 					 struct smc_clc_msg_proposal *pclc,
2264 					 struct smc_init_info *ini)
2265 {
2266 	struct smc_clc_v2_extension *smc_v2_ext;
2267 	u8 smcr_version;
2268 	int rc;
2269 
2270 	if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2271 		goto not_found;
2272 
2273 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2274 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2275 		goto not_found;
2276 
2277 	/* prepare RDMA check */
2278 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2279 	memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2280 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2281 	ini->check_smcrv2 = true;
2282 	ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2283 	ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2284 	ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2285 	rc = smc_find_rdma_device(new_smc, ini);
2286 	if (rc) {
2287 		smc_find_ism_store_rc(rc, ini);
2288 		goto not_found;
2289 	}
2290 	if (!ini->smcrv2.uses_gateway)
2291 		memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2292 
2293 	smcr_version = ini->smcr_version;
2294 	ini->smcr_version = SMC_V2;
2295 	rc = smc_listen_rdma_init(new_smc, ini);
2296 	if (!rc) {
2297 		rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2298 		if (rc)
2299 			smc_conn_abort(new_smc, ini->first_contact_local);
2300 	}
2301 	if (!rc)
2302 		return;
2303 	ini->smcr_version = smcr_version;
2304 	smc_find_ism_store_rc(rc, ini);
2305 
2306 not_found:
2307 	ini->smcr_version &= ~SMC_V2;
2308 	ini->smcrv2.ib_dev_v2 = NULL;
2309 	ini->check_smcrv2 = false;
2310 }
2311 
2312 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2313 					struct smc_clc_msg_proposal *pclc,
2314 					struct smc_init_info *ini)
2315 {
2316 	int rc;
2317 
2318 	if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2319 		return SMC_CLC_DECL_NOSMCDEV;
2320 
2321 	/* prepare RDMA check */
2322 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2323 	memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2324 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2325 	rc = smc_find_rdma_device(new_smc, ini);
2326 	if (rc) {
2327 		/* no RDMA device found */
2328 		return SMC_CLC_DECL_NOSMCDEV;
2329 	}
2330 	rc = smc_listen_rdma_init(new_smc, ini);
2331 	if (rc)
2332 		return rc;
2333 	return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2334 }
2335 
2336 /* determine the local device matching to proposal */
2337 static int smc_listen_find_device(struct smc_sock *new_smc,
2338 				  struct smc_clc_msg_proposal *pclc,
2339 				  struct smc_init_info *ini)
2340 {
2341 	int prfx_rc;
2342 
2343 	/* check for ISM device matching V2 proposed device */
2344 	smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2345 	if (ini->ism_dev[0])
2346 		return 0;
2347 
2348 	/* check for matching IP prefix and subnet length (V1) */
2349 	prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2350 	if (prfx_rc)
2351 		smc_find_ism_store_rc(prfx_rc, ini);
2352 
2353 	/* get vlan id from IP device */
2354 	if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2355 		return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2356 
2357 	/* check for ISM device matching V1 proposed device */
2358 	if (!prfx_rc)
2359 		smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2360 	if (ini->ism_dev[0])
2361 		return 0;
2362 
2363 	if (!smcr_indicated(pclc->hdr.typev1) &&
2364 	    !smcr_indicated(pclc->hdr.typev2))
2365 		/* skip RDMA and decline */
2366 		return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2367 
2368 	/* check if RDMA V2 is available */
2369 	smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2370 	if (ini->smcrv2.ib_dev_v2)
2371 		return 0;
2372 
2373 	/* check if RDMA V1 is available */
2374 	if (!prfx_rc) {
2375 		int rc;
2376 
2377 		rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2378 		smc_find_ism_store_rc(rc, ini);
2379 		return (!rc) ? 0 : ini->rc;
2380 	}
2381 	return prfx_rc;
2382 }
2383 
2384 /* listen worker: finish RDMA setup */
2385 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2386 				  struct smc_clc_msg_accept_confirm *cclc,
2387 				  bool local_first,
2388 				  struct smc_init_info *ini)
2389 {
2390 	struct smc_link *link = new_smc->conn.lnk;
2391 	int reason_code = 0;
2392 
2393 	if (local_first)
2394 		smc_link_save_peer_info(link, cclc, ini);
2395 
2396 	if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2397 		return SMC_CLC_DECL_ERR_RTOK;
2398 
2399 	if (local_first) {
2400 		if (smc_ib_ready_link(link))
2401 			return SMC_CLC_DECL_ERR_RDYLNK;
2402 		/* QP confirmation over RoCE fabric */
2403 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2404 		reason_code = smcr_serv_conf_first_link(new_smc);
2405 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2406 	}
2407 	return reason_code;
2408 }
2409 
2410 /* setup for connection of server */
2411 static void smc_listen_work(struct work_struct *work)
2412 {
2413 	struct smc_sock *new_smc = container_of(work, struct smc_sock,
2414 						smc_listen_work);
2415 	struct socket *newclcsock = new_smc->clcsock;
2416 	struct smc_clc_msg_accept_confirm *cclc;
2417 	struct smc_clc_msg_proposal_area *buf;
2418 	struct smc_clc_msg_proposal *pclc;
2419 	struct smc_init_info *ini = NULL;
2420 	u8 proposal_version = SMC_V1;
2421 	u8 accept_version;
2422 	int rc = 0;
2423 
2424 	if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2425 		return smc_listen_out_err(new_smc);
2426 
2427 	if (new_smc->use_fallback) {
2428 		smc_listen_out_connected(new_smc);
2429 		return;
2430 	}
2431 
2432 	/* check if peer is smc capable */
2433 	if (!tcp_sk(newclcsock->sk)->syn_smc) {
2434 		rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2435 		if (rc)
2436 			smc_listen_out_err(new_smc);
2437 		else
2438 			smc_listen_out_connected(new_smc);
2439 		return;
2440 	}
2441 
2442 	/* do inband token exchange -
2443 	 * wait for and receive SMC Proposal CLC message
2444 	 */
2445 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2446 	if (!buf) {
2447 		rc = SMC_CLC_DECL_MEM;
2448 		goto out_decl;
2449 	}
2450 	pclc = (struct smc_clc_msg_proposal *)buf;
2451 	rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2452 			      SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2453 	if (rc)
2454 		goto out_decl;
2455 
2456 	if (pclc->hdr.version > SMC_V1)
2457 		proposal_version = SMC_V2;
2458 
2459 	/* IPSec connections opt out of SMC optimizations */
2460 	if (using_ipsec(new_smc)) {
2461 		rc = SMC_CLC_DECL_IPSEC;
2462 		goto out_decl;
2463 	}
2464 
2465 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2466 	if (!ini) {
2467 		rc = SMC_CLC_DECL_MEM;
2468 		goto out_decl;
2469 	}
2470 
2471 	/* initial version checking */
2472 	rc = smc_listen_v2_check(new_smc, pclc, ini);
2473 	if (rc)
2474 		goto out_decl;
2475 
2476 	rc = smc_clc_srv_v2x_features_validate(new_smc, pclc, ini);
2477 	if (rc)
2478 		goto out_decl;
2479 
2480 	mutex_lock(&smc_server_lgr_pending);
2481 	smc_close_init(new_smc);
2482 	smc_rx_init(new_smc);
2483 	smc_tx_init(new_smc);
2484 
2485 	/* determine ISM or RoCE device used for connection */
2486 	rc = smc_listen_find_device(new_smc, pclc, ini);
2487 	if (rc)
2488 		goto out_unlock;
2489 
2490 	/* send SMC Accept CLC message */
2491 	accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2492 	rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2493 				 accept_version, ini->negotiated_eid, ini);
2494 	if (rc)
2495 		goto out_unlock;
2496 
2497 	/* SMC-D does not need this lock any more */
2498 	if (ini->is_smcd)
2499 		mutex_unlock(&smc_server_lgr_pending);
2500 
2501 	/* receive SMC Confirm CLC message */
2502 	memset(buf, 0, sizeof(*buf));
2503 	cclc = (struct smc_clc_msg_accept_confirm *)buf;
2504 	rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2505 			      SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2506 	if (rc) {
2507 		if (!ini->is_smcd)
2508 			goto out_unlock;
2509 		goto out_decl;
2510 	}
2511 
2512 	rc = smc_clc_v2x_features_confirm_check(cclc, ini);
2513 	if (rc) {
2514 		if (!ini->is_smcd)
2515 			goto out_unlock;
2516 		goto out_decl;
2517 	}
2518 
2519 	/* fce smc release version is needed in smc_listen_rdma_finish,
2520 	 * so save fce info here.
2521 	 */
2522 	smc_conn_save_peer_info_fce(new_smc, cclc);
2523 
2524 	/* finish worker */
2525 	if (!ini->is_smcd) {
2526 		rc = smc_listen_rdma_finish(new_smc, cclc,
2527 					    ini->first_contact_local, ini);
2528 		if (rc)
2529 			goto out_unlock;
2530 		mutex_unlock(&smc_server_lgr_pending);
2531 	}
2532 	smc_conn_save_peer_info(new_smc, cclc);
2533 
2534 	if (ini->is_smcd &&
2535 	    smc_ism_support_dmb_nocopy(new_smc->conn.lgr->smcd)) {
2536 		rc = smcd_buf_attach(new_smc);
2537 		if (rc)
2538 			goto out_decl;
2539 	}
2540 
2541 	smc_listen_out_connected(new_smc);
2542 	SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2543 	goto out_free;
2544 
2545 out_unlock:
2546 	mutex_unlock(&smc_server_lgr_pending);
2547 out_decl:
2548 	smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2549 			   proposal_version);
2550 out_free:
2551 	kfree(ini);
2552 	kfree(buf);
2553 }
2554 
2555 static void smc_tcp_listen_work(struct work_struct *work)
2556 {
2557 	struct smc_sock *lsmc = container_of(work, struct smc_sock,
2558 					     tcp_listen_work);
2559 	struct sock *lsk = &lsmc->sk;
2560 	struct smc_sock *new_smc;
2561 	int rc = 0;
2562 
2563 	lock_sock(lsk);
2564 	while (lsk->sk_state == SMC_LISTEN) {
2565 		rc = smc_clcsock_accept(lsmc, &new_smc);
2566 		if (rc) /* clcsock accept queue empty or error */
2567 			goto out;
2568 		if (!new_smc)
2569 			continue;
2570 
2571 		if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2572 			atomic_inc(&lsmc->queued_smc_hs);
2573 
2574 		new_smc->listen_smc = lsmc;
2575 		new_smc->use_fallback = lsmc->use_fallback;
2576 		new_smc->fallback_rsn = lsmc->fallback_rsn;
2577 		sock_hold(lsk); /* sock_put in smc_listen_work */
2578 		INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2579 		smc_copy_sock_settings_to_smc(new_smc);
2580 		sock_hold(&new_smc->sk); /* sock_put in passive closing */
2581 		if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2582 			sock_put(&new_smc->sk);
2583 	}
2584 
2585 out:
2586 	release_sock(lsk);
2587 	sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2588 }
2589 
2590 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2591 {
2592 	struct smc_sock *lsmc;
2593 
2594 	read_lock_bh(&listen_clcsock->sk_callback_lock);
2595 	lsmc = smc_clcsock_user_data(listen_clcsock);
2596 	if (!lsmc)
2597 		goto out;
2598 	lsmc->clcsk_data_ready(listen_clcsock);
2599 	if (lsmc->sk.sk_state == SMC_LISTEN) {
2600 		sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2601 		if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2602 			sock_put(&lsmc->sk);
2603 	}
2604 out:
2605 	read_unlock_bh(&listen_clcsock->sk_callback_lock);
2606 }
2607 
2608 static int smc_listen(struct socket *sock, int backlog)
2609 {
2610 	struct sock *sk = sock->sk;
2611 	struct smc_sock *smc;
2612 	int rc;
2613 
2614 	smc = smc_sk(sk);
2615 	lock_sock(sk);
2616 
2617 	rc = -EINVAL;
2618 	if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2619 	    smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2620 		goto out;
2621 
2622 	rc = 0;
2623 	if (sk->sk_state == SMC_LISTEN) {
2624 		sk->sk_max_ack_backlog = backlog;
2625 		goto out;
2626 	}
2627 	/* some socket options are handled in core, so we could not apply
2628 	 * them to the clc socket -- copy smc socket options to clc socket
2629 	 */
2630 	smc_copy_sock_settings_to_clc(smc);
2631 	if (!smc->use_fallback)
2632 		tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2633 
2634 	/* save original sk_data_ready function and establish
2635 	 * smc-specific sk_data_ready function
2636 	 */
2637 	write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2638 	smc->clcsock->sk->sk_user_data =
2639 		(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2640 	smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2641 			       smc_clcsock_data_ready, &smc->clcsk_data_ready);
2642 	write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2643 
2644 	/* save original ops */
2645 	smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2646 
2647 	smc->af_ops = *smc->ori_af_ops;
2648 	smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2649 
2650 	inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2651 
2652 	if (smc->limit_smc_hs)
2653 		tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2654 
2655 	rc = kernel_listen(smc->clcsock, backlog);
2656 	if (rc) {
2657 		write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2658 		smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2659 				       &smc->clcsk_data_ready);
2660 		smc->clcsock->sk->sk_user_data = NULL;
2661 		write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2662 		goto out;
2663 	}
2664 	sk->sk_max_ack_backlog = backlog;
2665 	sk->sk_ack_backlog = 0;
2666 	sk->sk_state = SMC_LISTEN;
2667 
2668 out:
2669 	release_sock(sk);
2670 	return rc;
2671 }
2672 
2673 static int smc_accept(struct socket *sock, struct socket *new_sock,
2674 		      struct proto_accept_arg *arg)
2675 {
2676 	struct sock *sk = sock->sk, *nsk;
2677 	DECLARE_WAITQUEUE(wait, current);
2678 	struct smc_sock *lsmc;
2679 	long timeo;
2680 	int rc = 0;
2681 
2682 	lsmc = smc_sk(sk);
2683 	sock_hold(sk); /* sock_put below */
2684 	lock_sock(sk);
2685 
2686 	if (lsmc->sk.sk_state != SMC_LISTEN) {
2687 		rc = -EINVAL;
2688 		release_sock(sk);
2689 		goto out;
2690 	}
2691 
2692 	/* Wait for an incoming connection */
2693 	timeo = sock_rcvtimeo(sk, arg->flags & O_NONBLOCK);
2694 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
2695 	while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2696 		set_current_state(TASK_INTERRUPTIBLE);
2697 		if (!timeo) {
2698 			rc = -EAGAIN;
2699 			break;
2700 		}
2701 		release_sock(sk);
2702 		timeo = schedule_timeout(timeo);
2703 		/* wakeup by sk_data_ready in smc_listen_work() */
2704 		sched_annotate_sleep();
2705 		lock_sock(sk);
2706 		if (signal_pending(current)) {
2707 			rc = sock_intr_errno(timeo);
2708 			break;
2709 		}
2710 	}
2711 	set_current_state(TASK_RUNNING);
2712 	remove_wait_queue(sk_sleep(sk), &wait);
2713 
2714 	if (!rc)
2715 		rc = sock_error(nsk);
2716 	release_sock(sk);
2717 	if (rc)
2718 		goto out;
2719 
2720 	if (lsmc->sockopt_defer_accept && !(arg->flags & O_NONBLOCK)) {
2721 		/* wait till data arrives on the socket */
2722 		timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2723 								MSEC_PER_SEC);
2724 		if (smc_sk(nsk)->use_fallback) {
2725 			struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2726 
2727 			lock_sock(clcsk);
2728 			if (skb_queue_empty(&clcsk->sk_receive_queue))
2729 				sk_wait_data(clcsk, &timeo, NULL);
2730 			release_sock(clcsk);
2731 		} else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2732 			lock_sock(nsk);
2733 			smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2734 			release_sock(nsk);
2735 		}
2736 	}
2737 
2738 out:
2739 	sock_put(sk); /* sock_hold above */
2740 	return rc;
2741 }
2742 
2743 static int smc_getname(struct socket *sock, struct sockaddr *addr,
2744 		       int peer)
2745 {
2746 	struct smc_sock *smc;
2747 
2748 	if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2749 	    (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2750 		return -ENOTCONN;
2751 
2752 	smc = smc_sk(sock->sk);
2753 
2754 	return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2755 }
2756 
2757 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2758 {
2759 	struct sock *sk = sock->sk;
2760 	struct smc_sock *smc;
2761 	int rc;
2762 
2763 	smc = smc_sk(sk);
2764 	lock_sock(sk);
2765 
2766 	/* SMC does not support connect with fastopen */
2767 	if (msg->msg_flags & MSG_FASTOPEN) {
2768 		/* not connected yet, fallback */
2769 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2770 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2771 			if (rc)
2772 				goto out;
2773 		} else {
2774 			rc = -EINVAL;
2775 			goto out;
2776 		}
2777 	} else if ((sk->sk_state != SMC_ACTIVE) &&
2778 		   (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2779 		   (sk->sk_state != SMC_INIT)) {
2780 		rc = -EPIPE;
2781 		goto out;
2782 	}
2783 
2784 	if (smc->use_fallback) {
2785 		rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2786 	} else {
2787 		rc = smc_tx_sendmsg(smc, msg, len);
2788 		SMC_STAT_TX_PAYLOAD(smc, len, rc);
2789 	}
2790 out:
2791 	release_sock(sk);
2792 	return rc;
2793 }
2794 
2795 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2796 		       int flags)
2797 {
2798 	struct sock *sk = sock->sk;
2799 	struct smc_sock *smc;
2800 	int rc = -ENOTCONN;
2801 
2802 	smc = smc_sk(sk);
2803 	lock_sock(sk);
2804 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2805 		/* socket was connected before, no more data to read */
2806 		rc = 0;
2807 		goto out;
2808 	}
2809 	if ((sk->sk_state == SMC_INIT) ||
2810 	    (sk->sk_state == SMC_LISTEN) ||
2811 	    (sk->sk_state == SMC_CLOSED))
2812 		goto out;
2813 
2814 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2815 		rc = 0;
2816 		goto out;
2817 	}
2818 
2819 	if (smc->use_fallback) {
2820 		rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2821 	} else {
2822 		msg->msg_namelen = 0;
2823 		rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2824 		SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2825 	}
2826 
2827 out:
2828 	release_sock(sk);
2829 	return rc;
2830 }
2831 
2832 static __poll_t smc_accept_poll(struct sock *parent)
2833 {
2834 	struct smc_sock *isk = smc_sk(parent);
2835 	__poll_t mask = 0;
2836 
2837 	spin_lock(&isk->accept_q_lock);
2838 	if (!list_empty(&isk->accept_q))
2839 		mask = EPOLLIN | EPOLLRDNORM;
2840 	spin_unlock(&isk->accept_q_lock);
2841 
2842 	return mask;
2843 }
2844 
2845 static __poll_t smc_poll(struct file *file, struct socket *sock,
2846 			     poll_table *wait)
2847 {
2848 	struct sock *sk = sock->sk;
2849 	struct smc_sock *smc;
2850 	__poll_t mask = 0;
2851 
2852 	if (!sk)
2853 		return EPOLLNVAL;
2854 
2855 	smc = smc_sk(sock->sk);
2856 	if (smc->use_fallback) {
2857 		/* delegate to CLC child sock */
2858 		mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2859 		sk->sk_err = smc->clcsock->sk->sk_err;
2860 	} else {
2861 		if (sk->sk_state != SMC_CLOSED)
2862 			sock_poll_wait(file, sock, wait);
2863 		if (sk->sk_err)
2864 			mask |= EPOLLERR;
2865 		if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2866 		    (sk->sk_state == SMC_CLOSED))
2867 			mask |= EPOLLHUP;
2868 		if (sk->sk_state == SMC_LISTEN) {
2869 			/* woken up by sk_data_ready in smc_listen_work() */
2870 			mask |= smc_accept_poll(sk);
2871 		} else if (smc->use_fallback) { /* as result of connect_work()*/
2872 			mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2873 							   wait);
2874 			sk->sk_err = smc->clcsock->sk->sk_err;
2875 		} else {
2876 			if ((sk->sk_state != SMC_INIT &&
2877 			     atomic_read(&smc->conn.sndbuf_space)) ||
2878 			    sk->sk_shutdown & SEND_SHUTDOWN) {
2879 				mask |= EPOLLOUT | EPOLLWRNORM;
2880 			} else {
2881 				sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2882 				set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2883 			}
2884 			if (atomic_read(&smc->conn.bytes_to_rcv))
2885 				mask |= EPOLLIN | EPOLLRDNORM;
2886 			if (sk->sk_shutdown & RCV_SHUTDOWN)
2887 				mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2888 			if (sk->sk_state == SMC_APPCLOSEWAIT1)
2889 				mask |= EPOLLIN;
2890 			if (smc->conn.urg_state == SMC_URG_VALID)
2891 				mask |= EPOLLPRI;
2892 		}
2893 	}
2894 
2895 	return mask;
2896 }
2897 
2898 static int smc_shutdown(struct socket *sock, int how)
2899 {
2900 	struct sock *sk = sock->sk;
2901 	bool do_shutdown = true;
2902 	struct smc_sock *smc;
2903 	int rc = -EINVAL;
2904 	int old_state;
2905 	int rc1 = 0;
2906 
2907 	smc = smc_sk(sk);
2908 
2909 	if ((how < SHUT_RD) || (how > SHUT_RDWR))
2910 		return rc;
2911 
2912 	lock_sock(sk);
2913 
2914 	if (sock->state == SS_CONNECTING) {
2915 		if (sk->sk_state == SMC_ACTIVE)
2916 			sock->state = SS_CONNECTED;
2917 		else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2918 			 sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2919 			 sk->sk_state == SMC_APPCLOSEWAIT1 ||
2920 			 sk->sk_state == SMC_APPCLOSEWAIT2 ||
2921 			 sk->sk_state == SMC_APPFINCLOSEWAIT)
2922 			sock->state = SS_DISCONNECTING;
2923 	}
2924 
2925 	rc = -ENOTCONN;
2926 	if ((sk->sk_state != SMC_ACTIVE) &&
2927 	    (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2928 	    (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2929 	    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2930 	    (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2931 	    (sk->sk_state != SMC_APPFINCLOSEWAIT))
2932 		goto out;
2933 	if (smc->use_fallback) {
2934 		rc = kernel_sock_shutdown(smc->clcsock, how);
2935 		sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2936 		if (sk->sk_shutdown == SHUTDOWN_MASK) {
2937 			sk->sk_state = SMC_CLOSED;
2938 			sk->sk_socket->state = SS_UNCONNECTED;
2939 			sock_put(sk);
2940 		}
2941 		goto out;
2942 	}
2943 	switch (how) {
2944 	case SHUT_RDWR:		/* shutdown in both directions */
2945 		old_state = sk->sk_state;
2946 		rc = smc_close_active(smc);
2947 		if (old_state == SMC_ACTIVE &&
2948 		    sk->sk_state == SMC_PEERCLOSEWAIT1)
2949 			do_shutdown = false;
2950 		break;
2951 	case SHUT_WR:
2952 		rc = smc_close_shutdown_write(smc);
2953 		break;
2954 	case SHUT_RD:
2955 		rc = 0;
2956 		/* nothing more to do because peer is not involved */
2957 		break;
2958 	}
2959 	if (do_shutdown && smc->clcsock)
2960 		rc1 = kernel_sock_shutdown(smc->clcsock, how);
2961 	/* map sock_shutdown_cmd constants to sk_shutdown value range */
2962 	sk->sk_shutdown |= how + 1;
2963 
2964 	if (sk->sk_state == SMC_CLOSED)
2965 		sock->state = SS_UNCONNECTED;
2966 	else
2967 		sock->state = SS_DISCONNECTING;
2968 out:
2969 	release_sock(sk);
2970 	return rc ? rc : rc1;
2971 }
2972 
2973 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2974 			    char __user *optval, int __user *optlen)
2975 {
2976 	struct smc_sock *smc;
2977 	int val, len;
2978 
2979 	smc = smc_sk(sock->sk);
2980 
2981 	if (get_user(len, optlen))
2982 		return -EFAULT;
2983 
2984 	len = min_t(int, len, sizeof(int));
2985 
2986 	if (len < 0)
2987 		return -EINVAL;
2988 
2989 	switch (optname) {
2990 	case SMC_LIMIT_HS:
2991 		val = smc->limit_smc_hs;
2992 		break;
2993 	default:
2994 		return -EOPNOTSUPP;
2995 	}
2996 
2997 	if (put_user(len, optlen))
2998 		return -EFAULT;
2999 	if (copy_to_user(optval, &val, len))
3000 		return -EFAULT;
3001 
3002 	return 0;
3003 }
3004 
3005 static int __smc_setsockopt(struct socket *sock, int level, int optname,
3006 			    sockptr_t optval, unsigned int optlen)
3007 {
3008 	struct sock *sk = sock->sk;
3009 	struct smc_sock *smc;
3010 	int val, rc;
3011 
3012 	smc = smc_sk(sk);
3013 
3014 	lock_sock(sk);
3015 	switch (optname) {
3016 	case SMC_LIMIT_HS:
3017 		if (optlen < sizeof(int)) {
3018 			rc = -EINVAL;
3019 			break;
3020 		}
3021 		if (copy_from_sockptr(&val, optval, sizeof(int))) {
3022 			rc = -EFAULT;
3023 			break;
3024 		}
3025 
3026 		smc->limit_smc_hs = !!val;
3027 		rc = 0;
3028 		break;
3029 	default:
3030 		rc = -EOPNOTSUPP;
3031 		break;
3032 	}
3033 	release_sock(sk);
3034 
3035 	return rc;
3036 }
3037 
3038 static int smc_setsockopt(struct socket *sock, int level, int optname,
3039 			  sockptr_t optval, unsigned int optlen)
3040 {
3041 	struct sock *sk = sock->sk;
3042 	struct smc_sock *smc;
3043 	int val, rc;
3044 
3045 	if (level == SOL_TCP && optname == TCP_ULP)
3046 		return -EOPNOTSUPP;
3047 	else if (level == SOL_SMC)
3048 		return __smc_setsockopt(sock, level, optname, optval, optlen);
3049 
3050 	smc = smc_sk(sk);
3051 
3052 	/* generic setsockopts reaching us here always apply to the
3053 	 * CLC socket
3054 	 */
3055 	mutex_lock(&smc->clcsock_release_lock);
3056 	if (!smc->clcsock) {
3057 		mutex_unlock(&smc->clcsock_release_lock);
3058 		return -EBADF;
3059 	}
3060 	if (unlikely(!smc->clcsock->ops->setsockopt))
3061 		rc = -EOPNOTSUPP;
3062 	else
3063 		rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
3064 						   optval, optlen);
3065 	if (smc->clcsock->sk->sk_err) {
3066 		sk->sk_err = smc->clcsock->sk->sk_err;
3067 		sk_error_report(sk);
3068 	}
3069 	mutex_unlock(&smc->clcsock_release_lock);
3070 
3071 	if (optlen < sizeof(int))
3072 		return -EINVAL;
3073 	if (copy_from_sockptr(&val, optval, sizeof(int)))
3074 		return -EFAULT;
3075 
3076 	lock_sock(sk);
3077 	if (rc || smc->use_fallback)
3078 		goto out;
3079 	switch (optname) {
3080 	case TCP_FASTOPEN:
3081 	case TCP_FASTOPEN_CONNECT:
3082 	case TCP_FASTOPEN_KEY:
3083 	case TCP_FASTOPEN_NO_COOKIE:
3084 		/* option not supported by SMC */
3085 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
3086 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
3087 		} else {
3088 			rc = -EINVAL;
3089 		}
3090 		break;
3091 	case TCP_NODELAY:
3092 		if (sk->sk_state != SMC_INIT &&
3093 		    sk->sk_state != SMC_LISTEN &&
3094 		    sk->sk_state != SMC_CLOSED) {
3095 			if (val) {
3096 				SMC_STAT_INC(smc, ndly_cnt);
3097 				smc_tx_pending(&smc->conn);
3098 				cancel_delayed_work(&smc->conn.tx_work);
3099 			}
3100 		}
3101 		break;
3102 	case TCP_CORK:
3103 		if (sk->sk_state != SMC_INIT &&
3104 		    sk->sk_state != SMC_LISTEN &&
3105 		    sk->sk_state != SMC_CLOSED) {
3106 			if (!val) {
3107 				SMC_STAT_INC(smc, cork_cnt);
3108 				smc_tx_pending(&smc->conn);
3109 				cancel_delayed_work(&smc->conn.tx_work);
3110 			}
3111 		}
3112 		break;
3113 	case TCP_DEFER_ACCEPT:
3114 		smc->sockopt_defer_accept = val;
3115 		break;
3116 	default:
3117 		break;
3118 	}
3119 out:
3120 	release_sock(sk);
3121 
3122 	return rc;
3123 }
3124 
3125 static int smc_getsockopt(struct socket *sock, int level, int optname,
3126 			  char __user *optval, int __user *optlen)
3127 {
3128 	struct smc_sock *smc;
3129 	int rc;
3130 
3131 	if (level == SOL_SMC)
3132 		return __smc_getsockopt(sock, level, optname, optval, optlen);
3133 
3134 	smc = smc_sk(sock->sk);
3135 	mutex_lock(&smc->clcsock_release_lock);
3136 	if (!smc->clcsock) {
3137 		mutex_unlock(&smc->clcsock_release_lock);
3138 		return -EBADF;
3139 	}
3140 	/* socket options apply to the CLC socket */
3141 	if (unlikely(!smc->clcsock->ops->getsockopt)) {
3142 		mutex_unlock(&smc->clcsock_release_lock);
3143 		return -EOPNOTSUPP;
3144 	}
3145 	rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3146 					   optval, optlen);
3147 	mutex_unlock(&smc->clcsock_release_lock);
3148 	return rc;
3149 }
3150 
3151 static int smc_ioctl(struct socket *sock, unsigned int cmd,
3152 		     unsigned long arg)
3153 {
3154 	union smc_host_cursor cons, urg;
3155 	struct smc_connection *conn;
3156 	struct smc_sock *smc;
3157 	int answ;
3158 
3159 	smc = smc_sk(sock->sk);
3160 	conn = &smc->conn;
3161 	lock_sock(&smc->sk);
3162 	if (smc->use_fallback) {
3163 		if (!smc->clcsock) {
3164 			release_sock(&smc->sk);
3165 			return -EBADF;
3166 		}
3167 		answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3168 		release_sock(&smc->sk);
3169 		return answ;
3170 	}
3171 	switch (cmd) {
3172 	case SIOCINQ: /* same as FIONREAD */
3173 		if (smc->sk.sk_state == SMC_LISTEN) {
3174 			release_sock(&smc->sk);
3175 			return -EINVAL;
3176 		}
3177 		if (smc->sk.sk_state == SMC_INIT ||
3178 		    smc->sk.sk_state == SMC_CLOSED)
3179 			answ = 0;
3180 		else
3181 			answ = atomic_read(&smc->conn.bytes_to_rcv);
3182 		break;
3183 	case SIOCOUTQ:
3184 		/* output queue size (not send + not acked) */
3185 		if (smc->sk.sk_state == SMC_LISTEN) {
3186 			release_sock(&smc->sk);
3187 			return -EINVAL;
3188 		}
3189 		if (smc->sk.sk_state == SMC_INIT ||
3190 		    smc->sk.sk_state == SMC_CLOSED)
3191 			answ = 0;
3192 		else
3193 			answ = smc->conn.sndbuf_desc->len -
3194 					atomic_read(&smc->conn.sndbuf_space);
3195 		break;
3196 	case SIOCOUTQNSD:
3197 		/* output queue size (not send only) */
3198 		if (smc->sk.sk_state == SMC_LISTEN) {
3199 			release_sock(&smc->sk);
3200 			return -EINVAL;
3201 		}
3202 		if (smc->sk.sk_state == SMC_INIT ||
3203 		    smc->sk.sk_state == SMC_CLOSED)
3204 			answ = 0;
3205 		else
3206 			answ = smc_tx_prepared_sends(&smc->conn);
3207 		break;
3208 	case SIOCATMARK:
3209 		if (smc->sk.sk_state == SMC_LISTEN) {
3210 			release_sock(&smc->sk);
3211 			return -EINVAL;
3212 		}
3213 		if (smc->sk.sk_state == SMC_INIT ||
3214 		    smc->sk.sk_state == SMC_CLOSED) {
3215 			answ = 0;
3216 		} else {
3217 			smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3218 			smc_curs_copy(&urg, &conn->urg_curs, conn);
3219 			answ = smc_curs_diff(conn->rmb_desc->len,
3220 					     &cons, &urg) == 1;
3221 		}
3222 		break;
3223 	default:
3224 		release_sock(&smc->sk);
3225 		return -ENOIOCTLCMD;
3226 	}
3227 	release_sock(&smc->sk);
3228 
3229 	return put_user(answ, (int __user *)arg);
3230 }
3231 
3232 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3233  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3234  * updates till whenever a respective page has been fully processed.
3235  * Note that subsequent recv() calls have to wait till all splice() processing
3236  * completed.
3237  */
3238 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3239 			       struct pipe_inode_info *pipe, size_t len,
3240 			       unsigned int flags)
3241 {
3242 	struct sock *sk = sock->sk;
3243 	struct smc_sock *smc;
3244 	int rc = -ENOTCONN;
3245 
3246 	smc = smc_sk(sk);
3247 	lock_sock(sk);
3248 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3249 		/* socket was connected before, no more data to read */
3250 		rc = 0;
3251 		goto out;
3252 	}
3253 	if (sk->sk_state == SMC_INIT ||
3254 	    sk->sk_state == SMC_LISTEN ||
3255 	    sk->sk_state == SMC_CLOSED)
3256 		goto out;
3257 
3258 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3259 		rc = 0;
3260 		goto out;
3261 	}
3262 
3263 	if (smc->use_fallback) {
3264 		rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3265 						    pipe, len, flags);
3266 	} else {
3267 		if (*ppos) {
3268 			rc = -ESPIPE;
3269 			goto out;
3270 		}
3271 		if (flags & SPLICE_F_NONBLOCK)
3272 			flags = MSG_DONTWAIT;
3273 		else
3274 			flags = 0;
3275 		SMC_STAT_INC(smc, splice_cnt);
3276 		rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3277 	}
3278 out:
3279 	release_sock(sk);
3280 
3281 	return rc;
3282 }
3283 
3284 /* must look like tcp */
3285 static const struct proto_ops smc_sock_ops = {
3286 	.family		= PF_SMC,
3287 	.owner		= THIS_MODULE,
3288 	.release	= smc_release,
3289 	.bind		= smc_bind,
3290 	.connect	= smc_connect,
3291 	.socketpair	= sock_no_socketpair,
3292 	.accept		= smc_accept,
3293 	.getname	= smc_getname,
3294 	.poll		= smc_poll,
3295 	.ioctl		= smc_ioctl,
3296 	.listen		= smc_listen,
3297 	.shutdown	= smc_shutdown,
3298 	.setsockopt	= smc_setsockopt,
3299 	.getsockopt	= smc_getsockopt,
3300 	.sendmsg	= smc_sendmsg,
3301 	.recvmsg	= smc_recvmsg,
3302 	.mmap		= sock_no_mmap,
3303 	.splice_read	= smc_splice_read,
3304 };
3305 
3306 static int __smc_create(struct net *net, struct socket *sock, int protocol,
3307 			int kern, struct socket *clcsock)
3308 {
3309 	int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3310 	struct smc_sock *smc;
3311 	struct sock *sk;
3312 	int rc;
3313 
3314 	rc = -ESOCKTNOSUPPORT;
3315 	if (sock->type != SOCK_STREAM)
3316 		goto out;
3317 
3318 	rc = -EPROTONOSUPPORT;
3319 	if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3320 		goto out;
3321 
3322 	rc = -ENOBUFS;
3323 	sock->ops = &smc_sock_ops;
3324 	sock->state = SS_UNCONNECTED;
3325 	sk = smc_sock_alloc(net, sock, protocol);
3326 	if (!sk)
3327 		goto out;
3328 
3329 	/* create internal TCP socket for CLC handshake and fallback */
3330 	smc = smc_sk(sk);
3331 	smc->use_fallback = false; /* assume rdma capability first */
3332 	smc->fallback_rsn = 0;
3333 
3334 	/* default behavior from limit_smc_hs in every net namespace */
3335 	smc->limit_smc_hs = net->smc.limit_smc_hs;
3336 
3337 	rc = 0;
3338 	if (!clcsock) {
3339 		rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3340 				      &smc->clcsock);
3341 		if (rc) {
3342 			sk_common_release(sk);
3343 			goto out;
3344 		}
3345 
3346 		/* smc_clcsock_release() does not wait smc->clcsock->sk's
3347 		 * destruction;  its sk_state might not be TCP_CLOSE after
3348 		 * smc->sk is close()d, and TCP timers can be fired later,
3349 		 * which need net ref.
3350 		 */
3351 		sk = smc->clcsock->sk;
3352 		__netns_tracker_free(net, &sk->ns_tracker, false);
3353 		sk->sk_net_refcnt = 1;
3354 		get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
3355 		sock_inuse_add(net, 1);
3356 	} else {
3357 		smc->clcsock = clcsock;
3358 	}
3359 
3360 out:
3361 	return rc;
3362 }
3363 
3364 static int smc_create(struct net *net, struct socket *sock, int protocol,
3365 		      int kern)
3366 {
3367 	return __smc_create(net, sock, protocol, kern, NULL);
3368 }
3369 
3370 static const struct net_proto_family smc_sock_family_ops = {
3371 	.family	= PF_SMC,
3372 	.owner	= THIS_MODULE,
3373 	.create	= smc_create,
3374 };
3375 
3376 static int smc_ulp_init(struct sock *sk)
3377 {
3378 	struct socket *tcp = sk->sk_socket;
3379 	struct net *net = sock_net(sk);
3380 	struct socket *smcsock;
3381 	int protocol, ret;
3382 
3383 	/* only TCP can be replaced */
3384 	if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3385 	    (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3386 		return -ESOCKTNOSUPPORT;
3387 	/* don't handle wq now */
3388 	if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3389 		return -ENOTCONN;
3390 
3391 	if (sk->sk_family == AF_INET)
3392 		protocol = SMCPROTO_SMC;
3393 	else
3394 		protocol = SMCPROTO_SMC6;
3395 
3396 	smcsock = sock_alloc();
3397 	if (!smcsock)
3398 		return -ENFILE;
3399 
3400 	smcsock->type = SOCK_STREAM;
3401 	__module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3402 	ret = __smc_create(net, smcsock, protocol, 1, tcp);
3403 	if (ret) {
3404 		sock_release(smcsock); /* module_put() which ops won't be NULL */
3405 		return ret;
3406 	}
3407 
3408 	/* replace tcp socket to smc */
3409 	smcsock->file = tcp->file;
3410 	smcsock->file->private_data = smcsock;
3411 	smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3412 	smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3413 	tcp->file = NULL;
3414 
3415 	return ret;
3416 }
3417 
3418 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3419 			  const gfp_t priority)
3420 {
3421 	struct inet_connection_sock *icsk = inet_csk(newsk);
3422 
3423 	/* don't inherit ulp ops to child when listen */
3424 	icsk->icsk_ulp_ops = NULL;
3425 }
3426 
3427 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3428 	.name		= "smc",
3429 	.owner		= THIS_MODULE,
3430 	.init		= smc_ulp_init,
3431 	.clone		= smc_ulp_clone,
3432 };
3433 
3434 unsigned int smc_net_id;
3435 
3436 static __net_init int smc_net_init(struct net *net)
3437 {
3438 	int rc;
3439 
3440 	rc = smc_sysctl_net_init(net);
3441 	if (rc)
3442 		return rc;
3443 	return smc_pnet_net_init(net);
3444 }
3445 
3446 static void __net_exit smc_net_exit(struct net *net)
3447 {
3448 	smc_sysctl_net_exit(net);
3449 	smc_pnet_net_exit(net);
3450 }
3451 
3452 static __net_init int smc_net_stat_init(struct net *net)
3453 {
3454 	return smc_stats_init(net);
3455 }
3456 
3457 static void __net_exit smc_net_stat_exit(struct net *net)
3458 {
3459 	smc_stats_exit(net);
3460 }
3461 
3462 static struct pernet_operations smc_net_ops = {
3463 	.init = smc_net_init,
3464 	.exit = smc_net_exit,
3465 	.id   = &smc_net_id,
3466 	.size = sizeof(struct smc_net),
3467 };
3468 
3469 static struct pernet_operations smc_net_stat_ops = {
3470 	.init = smc_net_stat_init,
3471 	.exit = smc_net_stat_exit,
3472 };
3473 
3474 static int __init smc_init(void)
3475 {
3476 	int rc;
3477 
3478 	rc = register_pernet_subsys(&smc_net_ops);
3479 	if (rc)
3480 		return rc;
3481 
3482 	rc = register_pernet_subsys(&smc_net_stat_ops);
3483 	if (rc)
3484 		goto out_pernet_subsys;
3485 
3486 	rc = smc_ism_init();
3487 	if (rc)
3488 		goto out_pernet_subsys_stat;
3489 	smc_clc_init();
3490 
3491 	rc = smc_nl_init();
3492 	if (rc)
3493 		goto out_ism;
3494 
3495 	rc = smc_pnet_init();
3496 	if (rc)
3497 		goto out_nl;
3498 
3499 	rc = -ENOMEM;
3500 
3501 	smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3502 	if (!smc_tcp_ls_wq)
3503 		goto out_pnet;
3504 
3505 	smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3506 	if (!smc_hs_wq)
3507 		goto out_alloc_tcp_ls_wq;
3508 
3509 	smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3510 	if (!smc_close_wq)
3511 		goto out_alloc_hs_wq;
3512 
3513 	rc = smc_core_init();
3514 	if (rc) {
3515 		pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3516 		goto out_alloc_wqs;
3517 	}
3518 
3519 	rc = smc_llc_init();
3520 	if (rc) {
3521 		pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3522 		goto out_core;
3523 	}
3524 
3525 	rc = smc_cdc_init();
3526 	if (rc) {
3527 		pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3528 		goto out_core;
3529 	}
3530 
3531 	rc = proto_register(&smc_proto, 1);
3532 	if (rc) {
3533 		pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3534 		goto out_core;
3535 	}
3536 
3537 	rc = proto_register(&smc_proto6, 1);
3538 	if (rc) {
3539 		pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3540 		goto out_proto;
3541 	}
3542 
3543 	rc = sock_register(&smc_sock_family_ops);
3544 	if (rc) {
3545 		pr_err("%s: sock_register fails with %d\n", __func__, rc);
3546 		goto out_proto6;
3547 	}
3548 	INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3549 	INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3550 
3551 	rc = smc_ib_register_client();
3552 	if (rc) {
3553 		pr_err("%s: ib_register fails with %d\n", __func__, rc);
3554 		goto out_sock;
3555 	}
3556 
3557 	rc = smc_loopback_init();
3558 	if (rc) {
3559 		pr_err("%s: smc_loopback_init fails with %d\n", __func__, rc);
3560 		goto out_ib;
3561 	}
3562 
3563 	rc = tcp_register_ulp(&smc_ulp_ops);
3564 	if (rc) {
3565 		pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3566 		goto out_lo;
3567 	}
3568 
3569 	static_branch_enable(&tcp_have_smc);
3570 	return 0;
3571 
3572 out_lo:
3573 	smc_loopback_exit();
3574 out_ib:
3575 	smc_ib_unregister_client();
3576 out_sock:
3577 	sock_unregister(PF_SMC);
3578 out_proto6:
3579 	proto_unregister(&smc_proto6);
3580 out_proto:
3581 	proto_unregister(&smc_proto);
3582 out_core:
3583 	smc_core_exit();
3584 out_alloc_wqs:
3585 	destroy_workqueue(smc_close_wq);
3586 out_alloc_hs_wq:
3587 	destroy_workqueue(smc_hs_wq);
3588 out_alloc_tcp_ls_wq:
3589 	destroy_workqueue(smc_tcp_ls_wq);
3590 out_pnet:
3591 	smc_pnet_exit();
3592 out_nl:
3593 	smc_nl_exit();
3594 out_ism:
3595 	smc_clc_exit();
3596 	smc_ism_exit();
3597 out_pernet_subsys_stat:
3598 	unregister_pernet_subsys(&smc_net_stat_ops);
3599 out_pernet_subsys:
3600 	unregister_pernet_subsys(&smc_net_ops);
3601 
3602 	return rc;
3603 }
3604 
3605 static void __exit smc_exit(void)
3606 {
3607 	static_branch_disable(&tcp_have_smc);
3608 	tcp_unregister_ulp(&smc_ulp_ops);
3609 	sock_unregister(PF_SMC);
3610 	smc_core_exit();
3611 	smc_loopback_exit();
3612 	smc_ib_unregister_client();
3613 	smc_ism_exit();
3614 	destroy_workqueue(smc_close_wq);
3615 	destroy_workqueue(smc_tcp_ls_wq);
3616 	destroy_workqueue(smc_hs_wq);
3617 	proto_unregister(&smc_proto6);
3618 	proto_unregister(&smc_proto);
3619 	smc_pnet_exit();
3620 	smc_nl_exit();
3621 	smc_clc_exit();
3622 	unregister_pernet_subsys(&smc_net_stat_ops);
3623 	unregister_pernet_subsys(&smc_net_ops);
3624 	rcu_barrier();
3625 }
3626 
3627 module_init(smc_init);
3628 module_exit(smc_exit);
3629 
3630 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3631 MODULE_DESCRIPTION("smc socket address family");
3632 MODULE_LICENSE("GPL");
3633 MODULE_ALIAS_NETPROTO(PF_SMC);
3634 MODULE_ALIAS_TCP_ULP("smc");
3635 MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);
3636