xref: /linux/net/smc/af_smc.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
4  *
5  *  AF_SMC protocol family socket handler keeping the AF_INET sock address type
6  *  applies to SOCK_STREAM sockets only
7  *  offers an alternative communication option for TCP-protocol sockets
8  *  applicable with RoCE-cards only
9  *
10  *  Initial restrictions:
11  *    - support for alternate links postponed
12  *
13  *  Copyright IBM Corp. 2016, 2018
14  *
15  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
16  *              based on prototype from Frank Blaschka
17  */
18 
19 #define KMSG_COMPONENT "smc"
20 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
21 
22 #include <linux/module.h>
23 #include <linux/socket.h>
24 #include <linux/workqueue.h>
25 #include <linux/in.h>
26 #include <linux/sched/signal.h>
27 #include <linux/if_vlan.h>
28 #include <linux/rcupdate_wait.h>
29 #include <linux/ctype.h>
30 #include <linux/splice.h>
31 
32 #include <net/sock.h>
33 #include <net/tcp.h>
34 #include <net/smc.h>
35 #include <asm/ioctls.h>
36 
37 #include <net/net_namespace.h>
38 #include <net/netns/generic.h>
39 #include "smc_netns.h"
40 
41 #include "smc.h"
42 #include "smc_clc.h"
43 #include "smc_llc.h"
44 #include "smc_cdc.h"
45 #include "smc_core.h"
46 #include "smc_ib.h"
47 #include "smc_ism.h"
48 #include "smc_pnet.h"
49 #include "smc_netlink.h"
50 #include "smc_tx.h"
51 #include "smc_rx.h"
52 #include "smc_close.h"
53 #include "smc_stats.h"
54 #include "smc_tracepoint.h"
55 #include "smc_sysctl.h"
56 #include "smc_loopback.h"
57 #include "smc_inet.h"
58 
59 static DEFINE_MUTEX(smc_server_lgr_pending);	/* serialize link group
60 						 * creation on server
61 						 */
62 static DEFINE_MUTEX(smc_client_lgr_pending);	/* serialize link group
63 						 * creation on client
64 						 */
65 
66 static struct workqueue_struct	*smc_tcp_ls_wq;	/* wq for tcp listen work */
67 struct workqueue_struct	*smc_hs_wq;	/* wq for handshake work */
68 struct workqueue_struct	*smc_close_wq;	/* wq for close work */
69 
70 static void smc_tcp_listen_work(struct work_struct *);
71 static void smc_connect_work(struct work_struct *);
72 
73 int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb)
74 {
75 	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
76 	void *hdr;
77 
78 	if (cb_ctx->pos[0])
79 		goto out;
80 
81 	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
82 			  &smc_gen_nl_family, NLM_F_MULTI,
83 			  SMC_NETLINK_DUMP_HS_LIMITATION);
84 	if (!hdr)
85 		return -ENOMEM;
86 
87 	if (nla_put_u8(skb, SMC_NLA_HS_LIMITATION_ENABLED,
88 		       sock_net(skb->sk)->smc.limit_smc_hs))
89 		goto err;
90 
91 	genlmsg_end(skb, hdr);
92 	cb_ctx->pos[0] = 1;
93 out:
94 	return skb->len;
95 err:
96 	genlmsg_cancel(skb, hdr);
97 	return -EMSGSIZE;
98 }
99 
100 int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
101 {
102 	sock_net(skb->sk)->smc.limit_smc_hs = true;
103 	return 0;
104 }
105 
106 int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
107 {
108 	sock_net(skb->sk)->smc.limit_smc_hs = false;
109 	return 0;
110 }
111 
112 static void smc_set_keepalive(struct sock *sk, int val)
113 {
114 	struct smc_sock *smc = smc_sk(sk);
115 
116 	smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
117 }
118 
119 static struct sock *smc_tcp_syn_recv_sock(const struct sock *sk,
120 					  struct sk_buff *skb,
121 					  struct request_sock *req,
122 					  struct dst_entry *dst,
123 					  struct request_sock *req_unhash,
124 					  bool *own_req)
125 {
126 	struct smc_sock *smc;
127 	struct sock *child;
128 
129 	smc = smc_clcsock_user_data(sk);
130 
131 	if (READ_ONCE(sk->sk_ack_backlog) + atomic_read(&smc->queued_smc_hs) >
132 				sk->sk_max_ack_backlog)
133 		goto drop;
134 
135 	if (sk_acceptq_is_full(&smc->sk)) {
136 		NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
137 		goto drop;
138 	}
139 
140 	/* passthrough to original syn recv sock fct */
141 	child = smc->ori_af_ops->syn_recv_sock(sk, skb, req, dst, req_unhash,
142 					       own_req);
143 	/* child must not inherit smc or its ops */
144 	if (child) {
145 		rcu_assign_sk_user_data(child, NULL);
146 
147 		/* v4-mapped sockets don't inherit parent ops. Don't restore. */
148 		if (inet_csk(child)->icsk_af_ops == inet_csk(sk)->icsk_af_ops)
149 			inet_csk(child)->icsk_af_ops = smc->ori_af_ops;
150 	}
151 	return child;
152 
153 drop:
154 	dst_release(dst);
155 	tcp_listendrop(sk);
156 	return NULL;
157 }
158 
159 static bool smc_hs_congested(const struct sock *sk)
160 {
161 	const struct smc_sock *smc;
162 
163 	smc = smc_clcsock_user_data(sk);
164 
165 	if (!smc)
166 		return true;
167 
168 	if (workqueue_congested(WORK_CPU_UNBOUND, smc_hs_wq))
169 		return true;
170 
171 	return false;
172 }
173 
174 struct smc_hashinfo smc_v4_hashinfo = {
175 	.lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
176 };
177 
178 struct smc_hashinfo smc_v6_hashinfo = {
179 	.lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
180 };
181 
182 int smc_hash_sk(struct sock *sk)
183 {
184 	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
185 	struct hlist_head *head;
186 
187 	head = &h->ht;
188 
189 	write_lock_bh(&h->lock);
190 	sk_add_node(sk, head);
191 	write_unlock_bh(&h->lock);
192 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
193 
194 	return 0;
195 }
196 
197 void smc_unhash_sk(struct sock *sk)
198 {
199 	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
200 
201 	write_lock_bh(&h->lock);
202 	if (sk_del_node_init(sk))
203 		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
204 	write_unlock_bh(&h->lock);
205 }
206 
207 /* This will be called before user really release sock_lock. So do the
208  * work which we didn't do because of user hold the sock_lock in the
209  * BH context
210  */
211 void smc_release_cb(struct sock *sk)
212 {
213 	struct smc_sock *smc = smc_sk(sk);
214 
215 	if (smc->conn.tx_in_release_sock) {
216 		smc_tx_pending(&smc->conn);
217 		smc->conn.tx_in_release_sock = false;
218 	}
219 }
220 
221 struct proto smc_proto = {
222 	.name		= "SMC",
223 	.owner		= THIS_MODULE,
224 	.keepalive	= smc_set_keepalive,
225 	.hash		= smc_hash_sk,
226 	.unhash		= smc_unhash_sk,
227 	.release_cb	= smc_release_cb,
228 	.obj_size	= sizeof(struct smc_sock),
229 	.h.smc_hash	= &smc_v4_hashinfo,
230 	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
231 };
232 EXPORT_SYMBOL_GPL(smc_proto);
233 
234 struct proto smc_proto6 = {
235 	.name		= "SMC6",
236 	.owner		= THIS_MODULE,
237 	.keepalive	= smc_set_keepalive,
238 	.hash		= smc_hash_sk,
239 	.unhash		= smc_unhash_sk,
240 	.release_cb	= smc_release_cb,
241 	.obj_size	= sizeof(struct smc_sock),
242 	.h.smc_hash	= &smc_v6_hashinfo,
243 	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
244 };
245 EXPORT_SYMBOL_GPL(smc_proto6);
246 
247 static void smc_fback_restore_callbacks(struct smc_sock *smc)
248 {
249 	struct sock *clcsk = smc->clcsock->sk;
250 
251 	write_lock_bh(&clcsk->sk_callback_lock);
252 	clcsk->sk_user_data = NULL;
253 
254 	smc_clcsock_restore_cb(&clcsk->sk_state_change, &smc->clcsk_state_change);
255 	smc_clcsock_restore_cb(&clcsk->sk_data_ready, &smc->clcsk_data_ready);
256 	smc_clcsock_restore_cb(&clcsk->sk_write_space, &smc->clcsk_write_space);
257 	smc_clcsock_restore_cb(&clcsk->sk_error_report, &smc->clcsk_error_report);
258 
259 	write_unlock_bh(&clcsk->sk_callback_lock);
260 }
261 
262 static void smc_restore_fallback_changes(struct smc_sock *smc)
263 {
264 	if (smc->clcsock->file) { /* non-accepted sockets have no file yet */
265 		smc->clcsock->file->private_data = smc->sk.sk_socket;
266 		smc->clcsock->file = NULL;
267 		smc_fback_restore_callbacks(smc);
268 	}
269 }
270 
271 static int __smc_release(struct smc_sock *smc)
272 {
273 	struct sock *sk = &smc->sk;
274 	int rc = 0;
275 
276 	if (!smc->use_fallback) {
277 		rc = smc_close_active(smc);
278 		smc_sock_set_flag(sk, SOCK_DEAD);
279 		sk->sk_shutdown |= SHUTDOWN_MASK;
280 	} else {
281 		if (sk->sk_state != SMC_CLOSED) {
282 			if (sk->sk_state != SMC_LISTEN &&
283 			    sk->sk_state != SMC_INIT)
284 				sock_put(sk); /* passive closing */
285 			if (sk->sk_state == SMC_LISTEN) {
286 				/* wake up clcsock accept */
287 				rc = kernel_sock_shutdown(smc->clcsock,
288 							  SHUT_RDWR);
289 			}
290 			sk->sk_state = SMC_CLOSED;
291 			sk->sk_state_change(sk);
292 		}
293 		smc_restore_fallback_changes(smc);
294 	}
295 
296 	sk->sk_prot->unhash(sk);
297 
298 	if (sk->sk_state == SMC_CLOSED) {
299 		if (smc->clcsock) {
300 			release_sock(sk);
301 			smc_clcsock_release(smc);
302 			lock_sock(sk);
303 		}
304 		if (!smc->use_fallback)
305 			smc_conn_free(&smc->conn);
306 	}
307 
308 	return rc;
309 }
310 
311 int smc_release(struct socket *sock)
312 {
313 	struct sock *sk = sock->sk;
314 	struct smc_sock *smc;
315 	int old_state, rc = 0;
316 
317 	if (!sk)
318 		goto out;
319 
320 	sock_hold(sk); /* sock_put below */
321 	smc = smc_sk(sk);
322 
323 	old_state = sk->sk_state;
324 
325 	/* cleanup for a dangling non-blocking connect */
326 	if (smc->connect_nonblock && old_state == SMC_INIT)
327 		tcp_abort(smc->clcsock->sk, ECONNABORTED);
328 
329 	if (cancel_work_sync(&smc->connect_work))
330 		sock_put(&smc->sk); /* sock_hold in smc_connect for passive closing */
331 
332 	if (sk->sk_state == SMC_LISTEN)
333 		/* smc_close_non_accepted() is called and acquires
334 		 * sock lock for child sockets again
335 		 */
336 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
337 	else
338 		lock_sock(sk);
339 
340 	if (old_state == SMC_INIT && sk->sk_state == SMC_ACTIVE &&
341 	    !smc->use_fallback)
342 		smc_close_active_abort(smc);
343 
344 	rc = __smc_release(smc);
345 
346 	/* detach socket */
347 	sock_orphan(sk);
348 	sock->sk = NULL;
349 	release_sock(sk);
350 
351 	sock_put(sk); /* sock_hold above */
352 	sock_put(sk); /* final sock_put */
353 out:
354 	return rc;
355 }
356 
357 static void smc_destruct(struct sock *sk)
358 {
359 	if (sk->sk_state != SMC_CLOSED)
360 		return;
361 	if (!sock_flag(sk, SOCK_DEAD))
362 		return;
363 }
364 
365 void smc_sk_init(struct net *net, struct sock *sk, int protocol)
366 {
367 	struct smc_sock *smc = smc_sk(sk);
368 
369 	sk->sk_state = SMC_INIT;
370 	sk->sk_destruct = smc_destruct;
371 	sk->sk_protocol = protocol;
372 	WRITE_ONCE(sk->sk_sndbuf, 2 * READ_ONCE(net->smc.sysctl_wmem));
373 	WRITE_ONCE(sk->sk_rcvbuf, 2 * READ_ONCE(net->smc.sysctl_rmem));
374 	INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
375 	INIT_WORK(&smc->connect_work, smc_connect_work);
376 	INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
377 	INIT_LIST_HEAD(&smc->accept_q);
378 	spin_lock_init(&smc->accept_q_lock);
379 	spin_lock_init(&smc->conn.send_lock);
380 	sk->sk_prot->hash(sk);
381 	mutex_init(&smc->clcsock_release_lock);
382 	smc_init_saved_callbacks(smc);
383 	smc->limit_smc_hs = net->smc.limit_smc_hs;
384 	smc->use_fallback = false; /* assume rdma capability first */
385 	smc->fallback_rsn = 0;
386 }
387 
388 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
389 				   int protocol)
390 {
391 	struct proto *prot;
392 	struct sock *sk;
393 
394 	prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
395 	sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
396 	if (!sk)
397 		return NULL;
398 
399 	sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
400 	smc_sk_init(net, sk, protocol);
401 
402 	return sk;
403 }
404 
405 int smc_bind(struct socket *sock, struct sockaddr *uaddr,
406 	     int addr_len)
407 {
408 	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
409 	struct sock *sk = sock->sk;
410 	struct smc_sock *smc;
411 	int rc;
412 
413 	smc = smc_sk(sk);
414 
415 	/* replicate tests from inet_bind(), to be safe wrt. future changes */
416 	rc = -EINVAL;
417 	if (addr_len < sizeof(struct sockaddr_in))
418 		goto out;
419 
420 	rc = -EAFNOSUPPORT;
421 	if (addr->sin_family != AF_INET &&
422 	    addr->sin_family != AF_INET6 &&
423 	    addr->sin_family != AF_UNSPEC)
424 		goto out;
425 	/* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
426 	if (addr->sin_family == AF_UNSPEC &&
427 	    addr->sin_addr.s_addr != htonl(INADDR_ANY))
428 		goto out;
429 
430 	lock_sock(sk);
431 
432 	/* Check if socket is already active */
433 	rc = -EINVAL;
434 	if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
435 		goto out_rel;
436 
437 	smc->clcsock->sk->sk_reuse = sk->sk_reuse;
438 	smc->clcsock->sk->sk_reuseport = sk->sk_reuseport;
439 	rc = kernel_bind(smc->clcsock, uaddr, addr_len);
440 
441 out_rel:
442 	release_sock(sk);
443 out:
444 	return rc;
445 }
446 
447 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
448  * clc socket (since smc is not called for these options from net/core)
449  */
450 
451 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
452 			     (1UL << SOCK_KEEPOPEN) | \
453 			     (1UL << SOCK_LINGER) | \
454 			     (1UL << SOCK_BROADCAST) | \
455 			     (1UL << SOCK_TIMESTAMP) | \
456 			     (1UL << SOCK_DBG) | \
457 			     (1UL << SOCK_RCVTSTAMP) | \
458 			     (1UL << SOCK_RCVTSTAMPNS) | \
459 			     (1UL << SOCK_LOCALROUTE) | \
460 			     (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
461 			     (1UL << SOCK_RXQ_OVFL) | \
462 			     (1UL << SOCK_WIFI_STATUS) | \
463 			     (1UL << SOCK_NOFCS) | \
464 			     (1UL << SOCK_FILTER_LOCKED) | \
465 			     (1UL << SOCK_TSTAMP_NEW))
466 
467 /* if set, use value set by setsockopt() - else use IPv4 or SMC sysctl value */
468 static void smc_adjust_sock_bufsizes(struct sock *nsk, struct sock *osk,
469 				     unsigned long mask)
470 {
471 	nsk->sk_userlocks = osk->sk_userlocks;
472 	if (osk->sk_userlocks & SOCK_SNDBUF_LOCK)
473 		nsk->sk_sndbuf = osk->sk_sndbuf;
474 	if (osk->sk_userlocks & SOCK_RCVBUF_LOCK)
475 		nsk->sk_rcvbuf = osk->sk_rcvbuf;
476 }
477 
478 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
479 				   unsigned long mask)
480 {
481 	/* options we don't get control via setsockopt for */
482 	nsk->sk_type = osk->sk_type;
483 	nsk->sk_sndtimeo = osk->sk_sndtimeo;
484 	nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
485 	nsk->sk_mark = READ_ONCE(osk->sk_mark);
486 	nsk->sk_priority = READ_ONCE(osk->sk_priority);
487 	nsk->sk_rcvlowat = osk->sk_rcvlowat;
488 	nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
489 	nsk->sk_err = osk->sk_err;
490 
491 	nsk->sk_flags &= ~mask;
492 	nsk->sk_flags |= osk->sk_flags & mask;
493 
494 	smc_adjust_sock_bufsizes(nsk, osk, mask);
495 }
496 
497 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
498 {
499 	smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
500 }
501 
502 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
503 			     (1UL << SOCK_KEEPOPEN) | \
504 			     (1UL << SOCK_LINGER) | \
505 			     (1UL << SOCK_DBG))
506 /* copy only settings and flags relevant for smc from clc to smc socket */
507 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
508 {
509 	smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
510 }
511 
512 /* register the new vzalloced sndbuf on all links */
513 static int smcr_lgr_reg_sndbufs(struct smc_link *link,
514 				struct smc_buf_desc *snd_desc)
515 {
516 	struct smc_link_group *lgr = link->lgr;
517 	int i, rc = 0;
518 
519 	if (!snd_desc->is_vm)
520 		return -EINVAL;
521 
522 	/* protect against parallel smcr_link_reg_buf() */
523 	down_write(&lgr->llc_conf_mutex);
524 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
525 		if (!smc_link_active(&lgr->lnk[i]))
526 			continue;
527 		rc = smcr_link_reg_buf(&lgr->lnk[i], snd_desc);
528 		if (rc)
529 			break;
530 	}
531 	up_write(&lgr->llc_conf_mutex);
532 	return rc;
533 }
534 
535 /* register the new rmb on all links */
536 static int smcr_lgr_reg_rmbs(struct smc_link *link,
537 			     struct smc_buf_desc *rmb_desc)
538 {
539 	struct smc_link_group *lgr = link->lgr;
540 	bool do_slow = false;
541 	int i, rc = 0;
542 
543 	rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
544 	if (rc)
545 		return rc;
546 
547 	down_read(&lgr->llc_conf_mutex);
548 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
549 		if (!smc_link_active(&lgr->lnk[i]))
550 			continue;
551 		if (!rmb_desc->is_reg_mr[link->link_idx]) {
552 			up_read(&lgr->llc_conf_mutex);
553 			goto slow_path;
554 		}
555 	}
556 	/* mr register already */
557 	goto fast_path;
558 slow_path:
559 	do_slow = true;
560 	/* protect against parallel smc_llc_cli_rkey_exchange() and
561 	 * parallel smcr_link_reg_buf()
562 	 */
563 	down_write(&lgr->llc_conf_mutex);
564 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
565 		if (!smc_link_active(&lgr->lnk[i]))
566 			continue;
567 		rc = smcr_link_reg_buf(&lgr->lnk[i], rmb_desc);
568 		if (rc)
569 			goto out;
570 	}
571 fast_path:
572 	/* exchange confirm_rkey msg with peer */
573 	rc = smc_llc_do_confirm_rkey(link, rmb_desc);
574 	if (rc) {
575 		rc = -EFAULT;
576 		goto out;
577 	}
578 	rmb_desc->is_conf_rkey = true;
579 out:
580 	do_slow ? up_write(&lgr->llc_conf_mutex) : up_read(&lgr->llc_conf_mutex);
581 	smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
582 	return rc;
583 }
584 
585 static int smcr_clnt_conf_first_link(struct smc_sock *smc)
586 {
587 	struct smc_link *link = smc->conn.lnk;
588 	struct smc_llc_qentry *qentry;
589 	int rc;
590 
591 	/* Receive CONFIRM LINK request from server over RoCE fabric.
592 	 * Increasing the client's timeout by twice as much as the server's
593 	 * timeout by default can temporarily avoid decline messages of
594 	 * both sides crossing or colliding
595 	 */
596 	qentry = smc_llc_wait(link->lgr, NULL, 2 * SMC_LLC_WAIT_TIME,
597 			      SMC_LLC_CONFIRM_LINK);
598 	if (!qentry) {
599 		struct smc_clc_msg_decline dclc;
600 
601 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
602 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
603 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
604 	}
605 	smc_llc_save_peer_uid(qentry);
606 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
607 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
608 	if (rc)
609 		return SMC_CLC_DECL_RMBE_EC;
610 
611 	rc = smc_ib_modify_qp_rts(link);
612 	if (rc)
613 		return SMC_CLC_DECL_ERR_RDYLNK;
614 
615 	smc_wr_remember_qp_attr(link);
616 
617 	/* reg the sndbuf if it was vzalloced */
618 	if (smc->conn.sndbuf_desc->is_vm) {
619 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
620 			return SMC_CLC_DECL_ERR_REGBUF;
621 	}
622 
623 	/* reg the rmb */
624 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
625 		return SMC_CLC_DECL_ERR_REGBUF;
626 
627 	/* confirm_rkey is implicit on 1st contact */
628 	smc->conn.rmb_desc->is_conf_rkey = true;
629 
630 	/* send CONFIRM LINK response over RoCE fabric */
631 	rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
632 	if (rc < 0)
633 		return SMC_CLC_DECL_TIMEOUT_CL;
634 
635 	smc_llc_link_active(link);
636 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
637 
638 	if (link->lgr->max_links > 1) {
639 		/* optional 2nd link, receive ADD LINK request from server */
640 		qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
641 				      SMC_LLC_ADD_LINK);
642 		if (!qentry) {
643 			struct smc_clc_msg_decline dclc;
644 
645 			rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
646 					      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
647 			if (rc == -EAGAIN)
648 				rc = 0; /* no DECLINE received, go with one link */
649 			return rc;
650 		}
651 		smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
652 		smc_llc_cli_add_link(link, qentry);
653 	}
654 	return 0;
655 }
656 
657 static bool smc_isascii(char *hostname)
658 {
659 	int i;
660 
661 	for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
662 		if (!isascii(hostname[i]))
663 			return false;
664 	return true;
665 }
666 
667 static void smc_conn_save_peer_info_fce(struct smc_sock *smc,
668 					struct smc_clc_msg_accept_confirm *clc)
669 {
670 	struct smc_clc_first_contact_ext *fce;
671 	int clc_v2_len;
672 
673 	if (clc->hdr.version == SMC_V1 ||
674 	    !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
675 		return;
676 
677 	if (smc->conn.lgr->is_smcd) {
678 		memcpy(smc->conn.lgr->negotiated_eid, clc->d1.eid,
679 		       SMC_MAX_EID_LEN);
680 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm, d1);
681 	} else {
682 		memcpy(smc->conn.lgr->negotiated_eid, clc->r1.eid,
683 		       SMC_MAX_EID_LEN);
684 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm, r1);
685 	}
686 	fce = (struct smc_clc_first_contact_ext *)(((u8 *)clc) + clc_v2_len);
687 	smc->conn.lgr->peer_os = fce->os_type;
688 	smc->conn.lgr->peer_smc_release = fce->release;
689 	if (smc_isascii(fce->hostname))
690 		memcpy(smc->conn.lgr->peer_hostname, fce->hostname,
691 		       SMC_MAX_HOSTNAME_LEN);
692 }
693 
694 static void smcr_conn_save_peer_info(struct smc_sock *smc,
695 				     struct smc_clc_msg_accept_confirm *clc)
696 {
697 	int bufsize = smc_uncompress_bufsize(clc->r0.rmbe_size);
698 
699 	smc->conn.peer_rmbe_idx = clc->r0.rmbe_idx;
700 	smc->conn.local_tx_ctrl.token = ntohl(clc->r0.rmbe_alert_token);
701 	smc->conn.peer_rmbe_size = bufsize;
702 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
703 	smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
704 }
705 
706 static void smcd_conn_save_peer_info(struct smc_sock *smc,
707 				     struct smc_clc_msg_accept_confirm *clc)
708 {
709 	int bufsize = smc_uncompress_bufsize(clc->d0.dmbe_size);
710 
711 	smc->conn.peer_rmbe_idx = clc->d0.dmbe_idx;
712 	smc->conn.peer_token = ntohll(clc->d0.token);
713 	/* msg header takes up space in the buffer */
714 	smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
715 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
716 	smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
717 }
718 
719 static void smc_conn_save_peer_info(struct smc_sock *smc,
720 				    struct smc_clc_msg_accept_confirm *clc)
721 {
722 	if (smc->conn.lgr->is_smcd)
723 		smcd_conn_save_peer_info(smc, clc);
724 	else
725 		smcr_conn_save_peer_info(smc, clc);
726 	smc_conn_save_peer_info_fce(smc, clc);
727 }
728 
729 static void smc_link_save_peer_info(struct smc_link *link,
730 				    struct smc_clc_msg_accept_confirm *clc,
731 				    struct smc_init_info *ini)
732 {
733 	link->peer_qpn = ntoh24(clc->r0.qpn);
734 	memcpy(link->peer_gid, ini->peer_gid, SMC_GID_SIZE);
735 	memcpy(link->peer_mac, ini->peer_mac, sizeof(link->peer_mac));
736 	link->peer_psn = ntoh24(clc->r0.psn);
737 	link->peer_mtu = clc->r0.qp_mtu;
738 }
739 
740 static void smc_stat_inc_fback_rsn_cnt(struct smc_sock *smc,
741 				       struct smc_stats_fback *fback_arr)
742 {
743 	int cnt;
744 
745 	for (cnt = 0; cnt < SMC_MAX_FBACK_RSN_CNT; cnt++) {
746 		if (fback_arr[cnt].fback_code == smc->fallback_rsn) {
747 			fback_arr[cnt].count++;
748 			break;
749 		}
750 		if (!fback_arr[cnt].fback_code) {
751 			fback_arr[cnt].fback_code = smc->fallback_rsn;
752 			fback_arr[cnt].count++;
753 			break;
754 		}
755 	}
756 }
757 
758 static void smc_stat_fallback(struct smc_sock *smc)
759 {
760 	struct net *net = sock_net(&smc->sk);
761 
762 	mutex_lock(&net->smc.mutex_fback_rsn);
763 	if (smc->listen_smc) {
764 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->srv);
765 		net->smc.fback_rsn->srv_fback_cnt++;
766 	} else {
767 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->clnt);
768 		net->smc.fback_rsn->clnt_fback_cnt++;
769 	}
770 	mutex_unlock(&net->smc.mutex_fback_rsn);
771 }
772 
773 /* must be called under rcu read lock */
774 static void smc_fback_wakeup_waitqueue(struct smc_sock *smc, void *key)
775 {
776 	struct socket_wq *wq;
777 	__poll_t flags;
778 
779 	wq = rcu_dereference(smc->sk.sk_wq);
780 	if (!skwq_has_sleeper(wq))
781 		return;
782 
783 	/* wake up smc sk->sk_wq */
784 	if (!key) {
785 		/* sk_state_change */
786 		wake_up_interruptible_all(&wq->wait);
787 	} else {
788 		flags = key_to_poll(key);
789 		if (flags & (EPOLLIN | EPOLLOUT))
790 			/* sk_data_ready or sk_write_space */
791 			wake_up_interruptible_sync_poll(&wq->wait, flags);
792 		else if (flags & EPOLLERR)
793 			/* sk_error_report */
794 			wake_up_interruptible_poll(&wq->wait, flags);
795 	}
796 }
797 
798 static int smc_fback_mark_woken(wait_queue_entry_t *wait,
799 				unsigned int mode, int sync, void *key)
800 {
801 	struct smc_mark_woken *mark =
802 		container_of(wait, struct smc_mark_woken, wait_entry);
803 
804 	mark->woken = true;
805 	mark->key = key;
806 	return 0;
807 }
808 
809 static void smc_fback_forward_wakeup(struct smc_sock *smc, struct sock *clcsk,
810 				     void (*clcsock_callback)(struct sock *sk))
811 {
812 	struct smc_mark_woken mark = { .woken = false };
813 	struct socket_wq *wq;
814 
815 	init_waitqueue_func_entry(&mark.wait_entry,
816 				  smc_fback_mark_woken);
817 	rcu_read_lock();
818 	wq = rcu_dereference(clcsk->sk_wq);
819 	if (!wq)
820 		goto out;
821 	add_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
822 	clcsock_callback(clcsk);
823 	remove_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
824 
825 	if (mark.woken)
826 		smc_fback_wakeup_waitqueue(smc, mark.key);
827 out:
828 	rcu_read_unlock();
829 }
830 
831 static void smc_fback_state_change(struct sock *clcsk)
832 {
833 	struct smc_sock *smc;
834 
835 	read_lock_bh(&clcsk->sk_callback_lock);
836 	smc = smc_clcsock_user_data(clcsk);
837 	if (smc)
838 		smc_fback_forward_wakeup(smc, clcsk,
839 					 smc->clcsk_state_change);
840 	read_unlock_bh(&clcsk->sk_callback_lock);
841 }
842 
843 static void smc_fback_data_ready(struct sock *clcsk)
844 {
845 	struct smc_sock *smc;
846 
847 	read_lock_bh(&clcsk->sk_callback_lock);
848 	smc = smc_clcsock_user_data(clcsk);
849 	if (smc)
850 		smc_fback_forward_wakeup(smc, clcsk,
851 					 smc->clcsk_data_ready);
852 	read_unlock_bh(&clcsk->sk_callback_lock);
853 }
854 
855 static void smc_fback_write_space(struct sock *clcsk)
856 {
857 	struct smc_sock *smc;
858 
859 	read_lock_bh(&clcsk->sk_callback_lock);
860 	smc = smc_clcsock_user_data(clcsk);
861 	if (smc)
862 		smc_fback_forward_wakeup(smc, clcsk,
863 					 smc->clcsk_write_space);
864 	read_unlock_bh(&clcsk->sk_callback_lock);
865 }
866 
867 static void smc_fback_error_report(struct sock *clcsk)
868 {
869 	struct smc_sock *smc;
870 
871 	read_lock_bh(&clcsk->sk_callback_lock);
872 	smc = smc_clcsock_user_data(clcsk);
873 	if (smc)
874 		smc_fback_forward_wakeup(smc, clcsk,
875 					 smc->clcsk_error_report);
876 	read_unlock_bh(&clcsk->sk_callback_lock);
877 }
878 
879 static void smc_fback_replace_callbacks(struct smc_sock *smc)
880 {
881 	struct sock *clcsk = smc->clcsock->sk;
882 
883 	write_lock_bh(&clcsk->sk_callback_lock);
884 	clcsk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
885 
886 	smc_clcsock_replace_cb(&clcsk->sk_state_change, smc_fback_state_change,
887 			       &smc->clcsk_state_change);
888 	smc_clcsock_replace_cb(&clcsk->sk_data_ready, smc_fback_data_ready,
889 			       &smc->clcsk_data_ready);
890 	smc_clcsock_replace_cb(&clcsk->sk_write_space, smc_fback_write_space,
891 			       &smc->clcsk_write_space);
892 	smc_clcsock_replace_cb(&clcsk->sk_error_report, smc_fback_error_report,
893 			       &smc->clcsk_error_report);
894 
895 	write_unlock_bh(&clcsk->sk_callback_lock);
896 }
897 
898 static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code)
899 {
900 	int rc = 0;
901 
902 	mutex_lock(&smc->clcsock_release_lock);
903 	if (!smc->clcsock) {
904 		rc = -EBADF;
905 		goto out;
906 	}
907 
908 	smc->use_fallback = true;
909 	smc->fallback_rsn = reason_code;
910 	smc_stat_fallback(smc);
911 	trace_smc_switch_to_fallback(smc, reason_code);
912 	if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
913 		smc->clcsock->file = smc->sk.sk_socket->file;
914 		smc->clcsock->file->private_data = smc->clcsock;
915 		smc->clcsock->wq.fasync_list =
916 			smc->sk.sk_socket->wq.fasync_list;
917 		smc->sk.sk_socket->wq.fasync_list = NULL;
918 
919 		/* There might be some wait entries remaining
920 		 * in smc sk->sk_wq and they should be woken up
921 		 * as clcsock's wait queue is woken up.
922 		 */
923 		smc_fback_replace_callbacks(smc);
924 	}
925 out:
926 	mutex_unlock(&smc->clcsock_release_lock);
927 	return rc;
928 }
929 
930 /* fall back during connect */
931 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
932 {
933 	struct net *net = sock_net(&smc->sk);
934 	int rc = 0;
935 
936 	rc = smc_switch_to_fallback(smc, reason_code);
937 	if (rc) { /* fallback fails */
938 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
939 		if (smc->sk.sk_state == SMC_INIT)
940 			sock_put(&smc->sk); /* passive closing */
941 		return rc;
942 	}
943 	smc_copy_sock_settings_to_clc(smc);
944 	smc->connect_nonblock = 0;
945 	if (smc->sk.sk_state == SMC_INIT)
946 		smc->sk.sk_state = SMC_ACTIVE;
947 	return 0;
948 }
949 
950 /* decline and fall back during connect */
951 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
952 					u8 version)
953 {
954 	struct net *net = sock_net(&smc->sk);
955 	int rc;
956 
957 	if (reason_code < 0) { /* error, fallback is not possible */
958 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
959 		if (smc->sk.sk_state == SMC_INIT)
960 			sock_put(&smc->sk); /* passive closing */
961 		return reason_code;
962 	}
963 	if (reason_code != SMC_CLC_DECL_PEERDECL) {
964 		rc = smc_clc_send_decline(smc, reason_code, version);
965 		if (rc < 0) {
966 			this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
967 			if (smc->sk.sk_state == SMC_INIT)
968 				sock_put(&smc->sk); /* passive closing */
969 			return rc;
970 		}
971 	}
972 	return smc_connect_fallback(smc, reason_code);
973 }
974 
975 static void smc_conn_abort(struct smc_sock *smc, int local_first)
976 {
977 	struct smc_connection *conn = &smc->conn;
978 	struct smc_link_group *lgr = conn->lgr;
979 	bool lgr_valid = false;
980 
981 	if (smc_conn_lgr_valid(conn))
982 		lgr_valid = true;
983 
984 	smc_conn_free(conn);
985 	if (local_first && lgr_valid)
986 		smc_lgr_cleanup_early(lgr);
987 }
988 
989 /* check if there is a rdma device available for this connection. */
990 /* called for connect and listen */
991 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
992 {
993 	/* PNET table look up: search active ib_device and port
994 	 * within same PNETID that also contains the ethernet device
995 	 * used for the internal TCP socket
996 	 */
997 	smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
998 	if (!ini->check_smcrv2 && !ini->ib_dev)
999 		return SMC_CLC_DECL_NOSMCRDEV;
1000 	if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
1001 		return SMC_CLC_DECL_NOSMCRDEV;
1002 	return 0;
1003 }
1004 
1005 /* check if there is an ISM device available for this connection. */
1006 /* called for connect and listen */
1007 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
1008 {
1009 	/* Find ISM device with same PNETID as connecting interface  */
1010 	smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
1011 	if (!ini->ism_dev[0])
1012 		return SMC_CLC_DECL_NOSMCDDEV;
1013 	else
1014 		ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
1015 	return 0;
1016 }
1017 
1018 /* is chid unique for the ism devices that are already determined? */
1019 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
1020 					   int cnt)
1021 {
1022 	int i = (!ini->ism_dev[0]) ? 1 : 0;
1023 
1024 	for (; i < cnt; i++)
1025 		if (ini->ism_chid[i] == chid)
1026 			return false;
1027 	return true;
1028 }
1029 
1030 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
1031  * PNETID matching net_device)
1032  */
1033 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
1034 				       struct smc_init_info *ini)
1035 {
1036 	int rc = SMC_CLC_DECL_NOSMCDDEV;
1037 	struct smcd_dev *smcd;
1038 	int i = 1, entry = 1;
1039 	bool is_emulated;
1040 	u16 chid;
1041 
1042 	if (smcd_indicated(ini->smc_type_v1))
1043 		rc = 0;		/* already initialized for V1 */
1044 	mutex_lock(&smcd_dev_list.mutex);
1045 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1046 		if (smcd->going_away || smcd == ini->ism_dev[0])
1047 			continue;
1048 		chid = smc_ism_get_chid(smcd);
1049 		if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
1050 			continue;
1051 		is_emulated = __smc_ism_is_emulated(chid);
1052 		if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
1053 		    smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
1054 			if (is_emulated && entry == SMCD_CLC_MAX_V2_GID_ENTRIES)
1055 				/* It's the last GID-CHID entry left in CLC
1056 				 * Proposal SMC-Dv2 extension, but an Emulated-
1057 				 * ISM device will take two entries. So give
1058 				 * up it and try the next potential ISM device.
1059 				 */
1060 				continue;
1061 			ini->ism_dev[i] = smcd;
1062 			ini->ism_chid[i] = chid;
1063 			ini->is_smcd = true;
1064 			rc = 0;
1065 			i++;
1066 			entry = is_emulated ? entry + 2 : entry + 1;
1067 			if (entry > SMCD_CLC_MAX_V2_GID_ENTRIES)
1068 				break;
1069 		}
1070 	}
1071 	mutex_unlock(&smcd_dev_list.mutex);
1072 	ini->ism_offered_cnt = i - 1;
1073 	if (!ini->ism_dev[0] && !ini->ism_dev[1])
1074 		ini->smcd_version = 0;
1075 
1076 	return rc;
1077 }
1078 
1079 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
1080 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
1081 				      struct smc_init_info *ini)
1082 {
1083 	if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
1084 		return SMC_CLC_DECL_ISMVLANERR;
1085 	return 0;
1086 }
1087 
1088 static int smc_find_proposal_devices(struct smc_sock *smc,
1089 				     struct smc_init_info *ini)
1090 {
1091 	int rc = 0;
1092 
1093 	/* check if there is an ism device available */
1094 	if (!(ini->smcd_version & SMC_V1) ||
1095 	    smc_find_ism_device(smc, ini) ||
1096 	    smc_connect_ism_vlan_setup(smc, ini))
1097 		ini->smcd_version &= ~SMC_V1;
1098 	/* else ISM V1 is supported for this connection */
1099 
1100 	/* check if there is an rdma device available */
1101 	if (!(ini->smcr_version & SMC_V1) ||
1102 	    smc_find_rdma_device(smc, ini))
1103 		ini->smcr_version &= ~SMC_V1;
1104 	/* else RDMA is supported for this connection */
1105 
1106 	ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
1107 					      ini->smcr_version & SMC_V1);
1108 
1109 	/* check if there is an ism v2 device available */
1110 	if (!(ini->smcd_version & SMC_V2) ||
1111 	    !smc_ism_is_v2_capable() ||
1112 	    smc_find_ism_v2_device_clnt(smc, ini))
1113 		ini->smcd_version &= ~SMC_V2;
1114 
1115 	/* check if there is an rdma v2 device available */
1116 	ini->check_smcrv2 = true;
1117 	ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
1118 	if (!(ini->smcr_version & SMC_V2) ||
1119 	    smc->clcsock->sk->sk_family != AF_INET ||
1120 	    !smc_clc_ueid_count() ||
1121 	    smc_find_rdma_device(smc, ini))
1122 		ini->smcr_version &= ~SMC_V2;
1123 	ini->check_smcrv2 = false;
1124 
1125 	ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
1126 					      ini->smcr_version & SMC_V2);
1127 
1128 	/* if neither ISM nor RDMA are supported, fallback */
1129 	if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
1130 		rc = SMC_CLC_DECL_NOSMCDEV;
1131 
1132 	return rc;
1133 }
1134 
1135 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
1136  * used, the VLAN ID will be registered again during the connection setup.
1137  */
1138 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
1139 					struct smc_init_info *ini)
1140 {
1141 	if (!smcd_indicated(ini->smc_type_v1))
1142 		return 0;
1143 	if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
1144 		return SMC_CLC_DECL_CNFERR;
1145 	return 0;
1146 }
1147 
1148 #define SMC_CLC_MAX_ACCEPT_LEN \
1149 	(sizeof(struct smc_clc_msg_accept_confirm) + \
1150 	 sizeof(struct smc_clc_first_contact_ext_v2x) + \
1151 	 sizeof(struct smc_clc_msg_trail))
1152 
1153 /* CLC handshake during connect */
1154 static int smc_connect_clc(struct smc_sock *smc,
1155 			   struct smc_clc_msg_accept_confirm *aclc,
1156 			   struct smc_init_info *ini)
1157 {
1158 	int rc = 0;
1159 
1160 	/* do inband token exchange */
1161 	rc = smc_clc_send_proposal(smc, ini);
1162 	if (rc)
1163 		return rc;
1164 	/* receive SMC Accept CLC message */
1165 	return smc_clc_wait_msg(smc, aclc, SMC_CLC_MAX_ACCEPT_LEN,
1166 				SMC_CLC_ACCEPT, CLC_WAIT_TIME);
1167 }
1168 
1169 void smc_fill_gid_list(struct smc_link_group *lgr,
1170 		       struct smc_gidlist *gidlist,
1171 		       struct smc_ib_device *known_dev, u8 *known_gid)
1172 {
1173 	struct smc_init_info *alt_ini = NULL;
1174 
1175 	memset(gidlist, 0, sizeof(*gidlist));
1176 	memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
1177 
1178 	alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
1179 	if (!alt_ini)
1180 		goto out;
1181 
1182 	alt_ini->vlan_id = lgr->vlan_id;
1183 	alt_ini->check_smcrv2 = true;
1184 	alt_ini->smcrv2.saddr = lgr->saddr;
1185 	smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
1186 
1187 	if (!alt_ini->smcrv2.ib_dev_v2)
1188 		goto out;
1189 
1190 	memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
1191 	       SMC_GID_SIZE);
1192 
1193 out:
1194 	kfree(alt_ini);
1195 }
1196 
1197 static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
1198 				       struct smc_clc_msg_accept_confirm *aclc,
1199 				       struct smc_init_info *ini)
1200 {
1201 	struct smc_clc_first_contact_ext *fce =
1202 		smc_get_clc_first_contact_ext(aclc, false);
1203 	struct net *net = sock_net(&smc->sk);
1204 	int rc;
1205 
1206 	if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1207 		return 0;
1208 
1209 	if (fce->v2_direct) {
1210 		memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1211 		ini->smcrv2.uses_gateway = false;
1212 	} else {
1213 		if (smc_ib_find_route(net, smc->clcsock->sk->sk_rcv_saddr,
1214 				      smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1215 				      ini->smcrv2.nexthop_mac,
1216 				      &ini->smcrv2.uses_gateway))
1217 			return SMC_CLC_DECL_NOROUTE;
1218 		if (!ini->smcrv2.uses_gateway) {
1219 			/* mismatch: peer claims indirect, but its direct */
1220 			return SMC_CLC_DECL_NOINDIRECT;
1221 		}
1222 	}
1223 
1224 	ini->release_nr = fce->release;
1225 	rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1226 	if (rc)
1227 		return rc;
1228 
1229 	return 0;
1230 }
1231 
1232 /* setup for RDMA connection of client */
1233 static int smc_connect_rdma(struct smc_sock *smc,
1234 			    struct smc_clc_msg_accept_confirm *aclc,
1235 			    struct smc_init_info *ini)
1236 {
1237 	int i, reason_code = 0;
1238 	struct smc_link *link;
1239 	u8 *eid = NULL;
1240 
1241 	ini->is_smcd = false;
1242 	ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1243 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1244 	memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1245 	memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1246 	memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1247 	ini->max_conns = SMC_CONN_PER_LGR_MAX;
1248 	ini->max_links = SMC_LINKS_ADD_LNK_MAX;
1249 
1250 	reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1251 	if (reason_code)
1252 		return reason_code;
1253 
1254 	mutex_lock(&smc_client_lgr_pending);
1255 	reason_code = smc_conn_create(smc, ini);
1256 	if (reason_code) {
1257 		mutex_unlock(&smc_client_lgr_pending);
1258 		return reason_code;
1259 	}
1260 
1261 	smc_conn_save_peer_info(smc, aclc);
1262 
1263 	if (ini->first_contact_local) {
1264 		link = smc->conn.lnk;
1265 	} else {
1266 		/* set link that was assigned by server */
1267 		link = NULL;
1268 		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1269 			struct smc_link *l = &smc->conn.lgr->lnk[i];
1270 
1271 			if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1272 			    !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1273 				    SMC_GID_SIZE) &&
1274 			    (aclc->hdr.version > SMC_V1 ||
1275 			     !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1276 				     sizeof(l->peer_mac)))) {
1277 				link = l;
1278 				break;
1279 			}
1280 		}
1281 		if (!link) {
1282 			reason_code = SMC_CLC_DECL_NOSRVLINK;
1283 			goto connect_abort;
1284 		}
1285 		smc_switch_link_and_count(&smc->conn, link);
1286 	}
1287 
1288 	/* create send buffer and rmb */
1289 	if (smc_buf_create(smc, false)) {
1290 		reason_code = SMC_CLC_DECL_MEM;
1291 		goto connect_abort;
1292 	}
1293 
1294 	if (ini->first_contact_local)
1295 		smc_link_save_peer_info(link, aclc, ini);
1296 
1297 	if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1298 		reason_code = SMC_CLC_DECL_ERR_RTOK;
1299 		goto connect_abort;
1300 	}
1301 
1302 	smc_close_init(smc);
1303 	smc_rx_init(smc);
1304 
1305 	if (ini->first_contact_local) {
1306 		if (smc_ib_ready_link(link)) {
1307 			reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1308 			goto connect_abort;
1309 		}
1310 	} else {
1311 		/* reg sendbufs if they were vzalloced */
1312 		if (smc->conn.sndbuf_desc->is_vm) {
1313 			if (smcr_lgr_reg_sndbufs(link, smc->conn.sndbuf_desc)) {
1314 				reason_code = SMC_CLC_DECL_ERR_REGBUF;
1315 				goto connect_abort;
1316 			}
1317 		}
1318 		if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1319 			reason_code = SMC_CLC_DECL_ERR_REGBUF;
1320 			goto connect_abort;
1321 		}
1322 	}
1323 
1324 	if (aclc->hdr.version > SMC_V1) {
1325 		eid = aclc->r1.eid;
1326 		if (ini->first_contact_local)
1327 			smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1328 					  link->smcibdev, link->gid);
1329 	}
1330 
1331 	reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1332 					   aclc->hdr.version, eid, ini);
1333 	if (reason_code)
1334 		goto connect_abort;
1335 
1336 	smc_tx_init(smc);
1337 
1338 	if (ini->first_contact_local) {
1339 		/* QP confirmation over RoCE fabric */
1340 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1341 		reason_code = smcr_clnt_conf_first_link(smc);
1342 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1343 		if (reason_code)
1344 			goto connect_abort;
1345 	}
1346 	mutex_unlock(&smc_client_lgr_pending);
1347 
1348 	smc_copy_sock_settings_to_clc(smc);
1349 	smc->connect_nonblock = 0;
1350 	if (smc->sk.sk_state == SMC_INIT)
1351 		smc->sk.sk_state = SMC_ACTIVE;
1352 
1353 	return 0;
1354 connect_abort:
1355 	smc_conn_abort(smc, ini->first_contact_local);
1356 	mutex_unlock(&smc_client_lgr_pending);
1357 	smc->connect_nonblock = 0;
1358 
1359 	return reason_code;
1360 }
1361 
1362 /* The server has chosen one of the proposed ISM devices for the communication.
1363  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1364  */
1365 static int
1366 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm *aclc,
1367 			       struct smc_init_info *ini)
1368 {
1369 	int i;
1370 
1371 	for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1372 		if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1373 			ini->ism_selected = i;
1374 			return 0;
1375 		}
1376 	}
1377 
1378 	return -EPROTO;
1379 }
1380 
1381 /* setup for ISM connection of client */
1382 static int smc_connect_ism(struct smc_sock *smc,
1383 			   struct smc_clc_msg_accept_confirm *aclc,
1384 			   struct smc_init_info *ini)
1385 {
1386 	u8 *eid = NULL;
1387 	int rc = 0;
1388 
1389 	ini->is_smcd = true;
1390 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1391 
1392 	if (aclc->hdr.version == SMC_V2) {
1393 		if (ini->first_contact_peer) {
1394 			struct smc_clc_first_contact_ext *fce =
1395 				smc_get_clc_first_contact_ext(aclc, true);
1396 
1397 			ini->release_nr = fce->release;
1398 			rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1399 			if (rc)
1400 				return rc;
1401 		}
1402 
1403 		rc = smc_v2_determine_accepted_chid(aclc, ini);
1404 		if (rc)
1405 			return rc;
1406 
1407 		if (__smc_ism_is_emulated(ini->ism_chid[ini->ism_selected]))
1408 			ini->ism_peer_gid[ini->ism_selected].gid_ext =
1409 						ntohll(aclc->d1.gid_ext);
1410 		/* for non-Emulated-ISM devices, peer gid_ext remains 0. */
1411 	}
1412 	ini->ism_peer_gid[ini->ism_selected].gid = ntohll(aclc->d0.gid);
1413 
1414 	/* there is only one lgr role for SMC-D; use server lock */
1415 	mutex_lock(&smc_server_lgr_pending);
1416 	rc = smc_conn_create(smc, ini);
1417 	if (rc) {
1418 		mutex_unlock(&smc_server_lgr_pending);
1419 		return rc;
1420 	}
1421 
1422 	/* Create send and receive buffers */
1423 	rc = smc_buf_create(smc, true);
1424 	if (rc) {
1425 		rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1426 		goto connect_abort;
1427 	}
1428 
1429 	smc_conn_save_peer_info(smc, aclc);
1430 
1431 	if (smc_ism_support_dmb_nocopy(smc->conn.lgr->smcd)) {
1432 		rc = smcd_buf_attach(smc);
1433 		if (rc) {
1434 			rc = SMC_CLC_DECL_MEM;	/* try to fallback */
1435 			goto connect_abort;
1436 		}
1437 	}
1438 	smc_close_init(smc);
1439 	smc_rx_init(smc);
1440 	smc_tx_init(smc);
1441 
1442 	if (aclc->hdr.version > SMC_V1)
1443 		eid = aclc->d1.eid;
1444 
1445 	rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1446 				  aclc->hdr.version, eid, ini);
1447 	if (rc)
1448 		goto connect_abort;
1449 	mutex_unlock(&smc_server_lgr_pending);
1450 
1451 	smc_copy_sock_settings_to_clc(smc);
1452 	smc->connect_nonblock = 0;
1453 	if (smc->sk.sk_state == SMC_INIT)
1454 		smc->sk.sk_state = SMC_ACTIVE;
1455 
1456 	return 0;
1457 connect_abort:
1458 	smc_conn_abort(smc, ini->first_contact_local);
1459 	mutex_unlock(&smc_server_lgr_pending);
1460 	smc->connect_nonblock = 0;
1461 
1462 	return rc;
1463 }
1464 
1465 /* check if received accept type and version matches a proposed one */
1466 static int smc_connect_check_aclc(struct smc_init_info *ini,
1467 				  struct smc_clc_msg_accept_confirm *aclc)
1468 {
1469 	if (aclc->hdr.version >= SMC_V2) {
1470 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1471 		     !smcr_indicated(ini->smc_type_v2)) ||
1472 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1473 		     !smcd_indicated(ini->smc_type_v2)))
1474 			return SMC_CLC_DECL_MODEUNSUPP;
1475 	} else {
1476 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1477 		     !smcr_indicated(ini->smc_type_v1)) ||
1478 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1479 		     !smcd_indicated(ini->smc_type_v1)))
1480 			return SMC_CLC_DECL_MODEUNSUPP;
1481 	}
1482 
1483 	return 0;
1484 }
1485 
1486 /* perform steps before actually connecting */
1487 static int __smc_connect(struct smc_sock *smc)
1488 {
1489 	u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1490 	struct smc_clc_msg_accept_confirm *aclc;
1491 	struct smc_init_info *ini = NULL;
1492 	u8 *buf = NULL;
1493 	int rc = 0;
1494 
1495 	if (smc->use_fallback)
1496 		return smc_connect_fallback(smc, smc->fallback_rsn);
1497 
1498 	/* if peer has not signalled SMC-capability, fall back */
1499 	if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1500 		return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1501 
1502 	/* IPSec connections opt out of SMC optimizations */
1503 	if (using_ipsec(smc))
1504 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1505 						    version);
1506 
1507 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1508 	if (!ini)
1509 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1510 						    version);
1511 
1512 	ini->smcd_version = SMC_V1 | SMC_V2;
1513 	ini->smcr_version = SMC_V1 | SMC_V2;
1514 	ini->smc_type_v1 = SMC_TYPE_B;
1515 	ini->smc_type_v2 = SMC_TYPE_B;
1516 
1517 	/* get vlan id from IP device */
1518 	if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1519 		ini->smcd_version &= ~SMC_V1;
1520 		ini->smcr_version = 0;
1521 		ini->smc_type_v1 = SMC_TYPE_N;
1522 	}
1523 
1524 	rc = smc_find_proposal_devices(smc, ini);
1525 	if (rc)
1526 		goto fallback;
1527 
1528 	buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1529 	if (!buf) {
1530 		rc = SMC_CLC_DECL_MEM;
1531 		goto fallback;
1532 	}
1533 	aclc = (struct smc_clc_msg_accept_confirm *)buf;
1534 
1535 	/* perform CLC handshake */
1536 	rc = smc_connect_clc(smc, aclc, ini);
1537 	if (rc) {
1538 		/* -EAGAIN on timeout, see tcp_recvmsg() */
1539 		if (rc == -EAGAIN) {
1540 			rc = -ETIMEDOUT;
1541 			smc->sk.sk_err = ETIMEDOUT;
1542 		}
1543 		goto vlan_cleanup;
1544 	}
1545 
1546 	/* check if smc modes and versions of CLC proposal and accept match */
1547 	rc = smc_connect_check_aclc(ini, aclc);
1548 	version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1549 	if (rc)
1550 		goto vlan_cleanup;
1551 
1552 	/* depending on previous steps, connect using rdma or ism */
1553 	if (aclc->hdr.typev1 == SMC_TYPE_R) {
1554 		ini->smcr_version = version;
1555 		rc = smc_connect_rdma(smc, aclc, ini);
1556 	} else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1557 		ini->smcd_version = version;
1558 		rc = smc_connect_ism(smc, aclc, ini);
1559 	}
1560 	if (rc)
1561 		goto vlan_cleanup;
1562 
1563 	SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1564 	smc_connect_ism_vlan_cleanup(smc, ini);
1565 	kfree(buf);
1566 	kfree(ini);
1567 	return 0;
1568 
1569 vlan_cleanup:
1570 	smc_connect_ism_vlan_cleanup(smc, ini);
1571 	kfree(buf);
1572 fallback:
1573 	kfree(ini);
1574 	return smc_connect_decline_fallback(smc, rc, version);
1575 }
1576 
1577 static void smc_connect_work(struct work_struct *work)
1578 {
1579 	struct smc_sock *smc = container_of(work, struct smc_sock,
1580 					    connect_work);
1581 	long timeo = smc->sk.sk_sndtimeo;
1582 	int rc = 0;
1583 
1584 	if (!timeo)
1585 		timeo = MAX_SCHEDULE_TIMEOUT;
1586 	lock_sock(smc->clcsock->sk);
1587 	if (smc->clcsock->sk->sk_err) {
1588 		smc->sk.sk_err = smc->clcsock->sk->sk_err;
1589 	} else if ((1 << smc->clcsock->sk->sk_state) &
1590 					(TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1591 		rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1592 		if ((rc == -EPIPE) &&
1593 		    ((1 << smc->clcsock->sk->sk_state) &
1594 					(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1595 			rc = 0;
1596 	}
1597 	release_sock(smc->clcsock->sk);
1598 	lock_sock(&smc->sk);
1599 	if (rc != 0 || smc->sk.sk_err) {
1600 		smc->sk.sk_state = SMC_CLOSED;
1601 		if (rc == -EPIPE || rc == -EAGAIN)
1602 			smc->sk.sk_err = EPIPE;
1603 		else if (rc == -ECONNREFUSED)
1604 			smc->sk.sk_err = ECONNREFUSED;
1605 		else if (signal_pending(current))
1606 			smc->sk.sk_err = -sock_intr_errno(timeo);
1607 		sock_put(&smc->sk); /* passive closing */
1608 		goto out;
1609 	}
1610 
1611 	rc = __smc_connect(smc);
1612 	if (rc < 0)
1613 		smc->sk.sk_err = -rc;
1614 
1615 out:
1616 	if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1617 		if (smc->sk.sk_err) {
1618 			smc->sk.sk_state_change(&smc->sk);
1619 		} else { /* allow polling before and after fallback decision */
1620 			smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1621 			smc->sk.sk_write_space(&smc->sk);
1622 		}
1623 	}
1624 	release_sock(&smc->sk);
1625 }
1626 
1627 int smc_connect(struct socket *sock, struct sockaddr *addr,
1628 		int alen, int flags)
1629 {
1630 	struct sock *sk = sock->sk;
1631 	struct smc_sock *smc;
1632 	int rc = -EINVAL;
1633 
1634 	smc = smc_sk(sk);
1635 
1636 	/* separate smc parameter checking to be safe */
1637 	if (alen < sizeof(addr->sa_family))
1638 		goto out_err;
1639 	if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1640 		goto out_err;
1641 
1642 	lock_sock(sk);
1643 	switch (sock->state) {
1644 	default:
1645 		rc = -EINVAL;
1646 		goto out;
1647 	case SS_CONNECTED:
1648 		rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1649 		goto out;
1650 	case SS_CONNECTING:
1651 		if (sk->sk_state == SMC_ACTIVE)
1652 			goto connected;
1653 		break;
1654 	case SS_UNCONNECTED:
1655 		sock->state = SS_CONNECTING;
1656 		break;
1657 	}
1658 
1659 	switch (sk->sk_state) {
1660 	default:
1661 		goto out;
1662 	case SMC_CLOSED:
1663 		rc = sock_error(sk) ? : -ECONNABORTED;
1664 		sock->state = SS_UNCONNECTED;
1665 		goto out;
1666 	case SMC_ACTIVE:
1667 		rc = -EISCONN;
1668 		goto out;
1669 	case SMC_INIT:
1670 		break;
1671 	}
1672 
1673 	smc_copy_sock_settings_to_clc(smc);
1674 	tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1675 	if (smc->connect_nonblock) {
1676 		rc = -EALREADY;
1677 		goto out;
1678 	}
1679 	rc = kernel_connect(smc->clcsock, addr, alen, flags);
1680 	if (rc && rc != -EINPROGRESS)
1681 		goto out;
1682 
1683 	if (smc->use_fallback) {
1684 		sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1685 		goto out;
1686 	}
1687 	sock_hold(&smc->sk); /* sock put in passive closing */
1688 	if (flags & O_NONBLOCK) {
1689 		if (queue_work(smc_hs_wq, &smc->connect_work))
1690 			smc->connect_nonblock = 1;
1691 		rc = -EINPROGRESS;
1692 		goto out;
1693 	} else {
1694 		rc = __smc_connect(smc);
1695 		if (rc < 0)
1696 			goto out;
1697 	}
1698 
1699 connected:
1700 	rc = 0;
1701 	sock->state = SS_CONNECTED;
1702 out:
1703 	release_sock(sk);
1704 out_err:
1705 	return rc;
1706 }
1707 
1708 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1709 {
1710 	struct socket *new_clcsock = NULL;
1711 	struct sock *lsk = &lsmc->sk;
1712 	struct sock *new_sk;
1713 	int rc = -EINVAL;
1714 
1715 	release_sock(lsk);
1716 	new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1717 	if (!new_sk) {
1718 		rc = -ENOMEM;
1719 		lsk->sk_err = ENOMEM;
1720 		*new_smc = NULL;
1721 		lock_sock(lsk);
1722 		goto out;
1723 	}
1724 	*new_smc = smc_sk(new_sk);
1725 
1726 	mutex_lock(&lsmc->clcsock_release_lock);
1727 	if (lsmc->clcsock)
1728 		rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1729 	mutex_unlock(&lsmc->clcsock_release_lock);
1730 	lock_sock(lsk);
1731 	if  (rc < 0 && rc != -EAGAIN)
1732 		lsk->sk_err = -rc;
1733 	if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1734 		new_sk->sk_prot->unhash(new_sk);
1735 		if (new_clcsock)
1736 			sock_release(new_clcsock);
1737 		new_sk->sk_state = SMC_CLOSED;
1738 		smc_sock_set_flag(new_sk, SOCK_DEAD);
1739 		sock_put(new_sk); /* final */
1740 		*new_smc = NULL;
1741 		goto out;
1742 	}
1743 
1744 	/* new clcsock has inherited the smc listen-specific sk_data_ready
1745 	 * function; switch it back to the original sk_data_ready function
1746 	 */
1747 	new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1748 
1749 	/* if new clcsock has also inherited the fallback-specific callback
1750 	 * functions, switch them back to the original ones.
1751 	 */
1752 	if (lsmc->use_fallback) {
1753 		if (lsmc->clcsk_state_change)
1754 			new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1755 		if (lsmc->clcsk_write_space)
1756 			new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1757 		if (lsmc->clcsk_error_report)
1758 			new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1759 	}
1760 
1761 	(*new_smc)->clcsock = new_clcsock;
1762 out:
1763 	return rc;
1764 }
1765 
1766 /* add a just created sock to the accept queue of the listen sock as
1767  * candidate for a following socket accept call from user space
1768  */
1769 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1770 {
1771 	struct smc_sock *par = smc_sk(parent);
1772 
1773 	sock_hold(sk); /* sock_put in smc_accept_unlink () */
1774 	spin_lock(&par->accept_q_lock);
1775 	list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1776 	spin_unlock(&par->accept_q_lock);
1777 	sk_acceptq_added(parent);
1778 }
1779 
1780 /* remove a socket from the accept queue of its parental listening socket */
1781 static void smc_accept_unlink(struct sock *sk)
1782 {
1783 	struct smc_sock *par = smc_sk(sk)->listen_smc;
1784 
1785 	spin_lock(&par->accept_q_lock);
1786 	list_del_init(&smc_sk(sk)->accept_q);
1787 	spin_unlock(&par->accept_q_lock);
1788 	sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1789 	sock_put(sk); /* sock_hold in smc_accept_enqueue */
1790 }
1791 
1792 /* remove a sock from the accept queue to bind it to a new socket created
1793  * for a socket accept call from user space
1794  */
1795 struct sock *smc_accept_dequeue(struct sock *parent,
1796 				struct socket *new_sock)
1797 {
1798 	struct smc_sock *isk, *n;
1799 	struct sock *new_sk;
1800 
1801 	list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1802 		new_sk = (struct sock *)isk;
1803 
1804 		smc_accept_unlink(new_sk);
1805 		if (new_sk->sk_state == SMC_CLOSED) {
1806 			new_sk->sk_prot->unhash(new_sk);
1807 			if (isk->clcsock) {
1808 				sock_release(isk->clcsock);
1809 				isk->clcsock = NULL;
1810 			}
1811 			sock_put(new_sk); /* final */
1812 			continue;
1813 		}
1814 		if (new_sock) {
1815 			sock_graft(new_sk, new_sock);
1816 			new_sock->state = SS_CONNECTED;
1817 			if (isk->use_fallback) {
1818 				smc_sk(new_sk)->clcsock->file = new_sock->file;
1819 				isk->clcsock->file->private_data = isk->clcsock;
1820 			}
1821 		}
1822 		return new_sk;
1823 	}
1824 	return NULL;
1825 }
1826 
1827 /* clean up for a created but never accepted sock */
1828 void smc_close_non_accepted(struct sock *sk)
1829 {
1830 	struct smc_sock *smc = smc_sk(sk);
1831 
1832 	sock_hold(sk); /* sock_put below */
1833 	lock_sock(sk);
1834 	if (!sk->sk_lingertime)
1835 		/* wait for peer closing */
1836 		WRITE_ONCE(sk->sk_lingertime, SMC_MAX_STREAM_WAIT_TIMEOUT);
1837 	__smc_release(smc);
1838 	release_sock(sk);
1839 	sock_put(sk); /* sock_hold above */
1840 	sock_put(sk); /* final sock_put */
1841 }
1842 
1843 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1844 {
1845 	struct smc_link *link = smc->conn.lnk;
1846 	struct smc_llc_qentry *qentry;
1847 	int rc;
1848 
1849 	/* reg the sndbuf if it was vzalloced*/
1850 	if (smc->conn.sndbuf_desc->is_vm) {
1851 		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
1852 			return SMC_CLC_DECL_ERR_REGBUF;
1853 	}
1854 
1855 	/* reg the rmb */
1856 	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
1857 		return SMC_CLC_DECL_ERR_REGBUF;
1858 
1859 	/* send CONFIRM LINK request to client over the RoCE fabric */
1860 	rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1861 	if (rc < 0)
1862 		return SMC_CLC_DECL_TIMEOUT_CL;
1863 
1864 	/* receive CONFIRM LINK response from client over the RoCE fabric */
1865 	qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1866 			      SMC_LLC_CONFIRM_LINK);
1867 	if (!qentry) {
1868 		struct smc_clc_msg_decline dclc;
1869 
1870 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1871 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1872 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1873 	}
1874 	smc_llc_save_peer_uid(qentry);
1875 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1876 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1877 	if (rc)
1878 		return SMC_CLC_DECL_RMBE_EC;
1879 
1880 	/* confirm_rkey is implicit on 1st contact */
1881 	smc->conn.rmb_desc->is_conf_rkey = true;
1882 
1883 	smc_llc_link_active(link);
1884 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1885 
1886 	if (link->lgr->max_links > 1) {
1887 		down_write(&link->lgr->llc_conf_mutex);
1888 		/* initial contact - try to establish second link */
1889 		smc_llc_srv_add_link(link, NULL);
1890 		up_write(&link->lgr->llc_conf_mutex);
1891 	}
1892 	return 0;
1893 }
1894 
1895 /* listen worker: finish */
1896 static void smc_listen_out(struct smc_sock *new_smc)
1897 {
1898 	struct smc_sock *lsmc = new_smc->listen_smc;
1899 	struct sock *newsmcsk = &new_smc->sk;
1900 
1901 	if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1902 		atomic_dec(&lsmc->queued_smc_hs);
1903 
1904 	if (lsmc->sk.sk_state == SMC_LISTEN) {
1905 		lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1906 		smc_accept_enqueue(&lsmc->sk, newsmcsk);
1907 		release_sock(&lsmc->sk);
1908 	} else { /* no longer listening */
1909 		smc_close_non_accepted(newsmcsk);
1910 	}
1911 
1912 	/* Wake up accept */
1913 	lsmc->sk.sk_data_ready(&lsmc->sk);
1914 	sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1915 }
1916 
1917 /* listen worker: finish in state connected */
1918 static void smc_listen_out_connected(struct smc_sock *new_smc)
1919 {
1920 	struct sock *newsmcsk = &new_smc->sk;
1921 
1922 	if (newsmcsk->sk_state == SMC_INIT)
1923 		newsmcsk->sk_state = SMC_ACTIVE;
1924 
1925 	smc_listen_out(new_smc);
1926 }
1927 
1928 /* listen worker: finish in error state */
1929 static void smc_listen_out_err(struct smc_sock *new_smc)
1930 {
1931 	struct sock *newsmcsk = &new_smc->sk;
1932 	struct net *net = sock_net(newsmcsk);
1933 
1934 	this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1935 	if (newsmcsk->sk_state == SMC_INIT)
1936 		sock_put(&new_smc->sk); /* passive closing */
1937 	newsmcsk->sk_state = SMC_CLOSED;
1938 
1939 	smc_listen_out(new_smc);
1940 }
1941 
1942 /* listen worker: decline and fall back if possible */
1943 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1944 			       int local_first, u8 version)
1945 {
1946 	/* RDMA setup failed, switch back to TCP */
1947 	smc_conn_abort(new_smc, local_first);
1948 	if (reason_code < 0 ||
1949 	    smc_switch_to_fallback(new_smc, reason_code)) {
1950 		/* error, no fallback possible */
1951 		smc_listen_out_err(new_smc);
1952 		return;
1953 	}
1954 	if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1955 		if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1956 			smc_listen_out_err(new_smc);
1957 			return;
1958 		}
1959 	}
1960 	smc_listen_out_connected(new_smc);
1961 }
1962 
1963 /* listen worker: version checking */
1964 static int smc_listen_v2_check(struct smc_sock *new_smc,
1965 			       struct smc_clc_msg_proposal *pclc,
1966 			       struct smc_init_info *ini)
1967 {
1968 	struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1969 	struct smc_clc_v2_extension *pclc_v2_ext;
1970 	int rc = SMC_CLC_DECL_PEERNOSMC;
1971 
1972 	ini->smc_type_v1 = pclc->hdr.typev1;
1973 	ini->smc_type_v2 = pclc->hdr.typev2;
1974 	ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1975 	ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1976 	if (pclc->hdr.version > SMC_V1) {
1977 		if (smcd_indicated(ini->smc_type_v2))
1978 			ini->smcd_version |= SMC_V2;
1979 		if (smcr_indicated(ini->smc_type_v2))
1980 			ini->smcr_version |= SMC_V2;
1981 	}
1982 	if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1983 		rc = SMC_CLC_DECL_PEERNOSMC;
1984 		goto out;
1985 	}
1986 	pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1987 	if (!pclc_v2_ext) {
1988 		ini->smcd_version &= ~SMC_V2;
1989 		ini->smcr_version &= ~SMC_V2;
1990 		rc = SMC_CLC_DECL_NOV2EXT;
1991 		goto out;
1992 	}
1993 	pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
1994 	if (ini->smcd_version & SMC_V2) {
1995 		if (!smc_ism_is_v2_capable()) {
1996 			ini->smcd_version &= ~SMC_V2;
1997 			rc = SMC_CLC_DECL_NOISM2SUPP;
1998 		} else if (!pclc_smcd_v2_ext) {
1999 			ini->smcd_version &= ~SMC_V2;
2000 			rc = SMC_CLC_DECL_NOV2DEXT;
2001 		} else if (!pclc_v2_ext->hdr.eid_cnt &&
2002 			   !pclc_v2_ext->hdr.flag.seid) {
2003 			ini->smcd_version &= ~SMC_V2;
2004 			rc = SMC_CLC_DECL_NOUEID;
2005 		}
2006 	}
2007 	if (ini->smcr_version & SMC_V2) {
2008 		if (!pclc_v2_ext->hdr.eid_cnt) {
2009 			ini->smcr_version &= ~SMC_V2;
2010 			rc = SMC_CLC_DECL_NOUEID;
2011 		}
2012 	}
2013 
2014 	ini->release_nr = pclc_v2_ext->hdr.flag.release;
2015 	if (pclc_v2_ext->hdr.flag.release > SMC_RELEASE)
2016 		ini->release_nr = SMC_RELEASE;
2017 
2018 out:
2019 	if (!ini->smcd_version && !ini->smcr_version)
2020 		return rc;
2021 
2022 	return 0;
2023 }
2024 
2025 /* listen worker: check prefixes */
2026 static int smc_listen_prfx_check(struct smc_sock *new_smc,
2027 				 struct smc_clc_msg_proposal *pclc)
2028 {
2029 	struct smc_clc_msg_proposal_prefix *pclc_prfx;
2030 	struct socket *newclcsock = new_smc->clcsock;
2031 
2032 	if (pclc->hdr.typev1 == SMC_TYPE_N)
2033 		return 0;
2034 	pclc_prfx = smc_clc_proposal_get_prefix(pclc);
2035 	if (smc_clc_prfx_match(newclcsock, pclc_prfx))
2036 		return SMC_CLC_DECL_DIFFPREFIX;
2037 
2038 	return 0;
2039 }
2040 
2041 /* listen worker: initialize connection and buffers */
2042 static int smc_listen_rdma_init(struct smc_sock *new_smc,
2043 				struct smc_init_info *ini)
2044 {
2045 	int rc;
2046 
2047 	/* allocate connection / link group */
2048 	rc = smc_conn_create(new_smc, ini);
2049 	if (rc)
2050 		return rc;
2051 
2052 	/* create send buffer and rmb */
2053 	if (smc_buf_create(new_smc, false)) {
2054 		smc_conn_abort(new_smc, ini->first_contact_local);
2055 		return SMC_CLC_DECL_MEM;
2056 	}
2057 
2058 	return 0;
2059 }
2060 
2061 /* listen worker: initialize connection and buffers for SMC-D */
2062 static int smc_listen_ism_init(struct smc_sock *new_smc,
2063 			       struct smc_init_info *ini)
2064 {
2065 	int rc;
2066 
2067 	rc = smc_conn_create(new_smc, ini);
2068 	if (rc)
2069 		return rc;
2070 
2071 	/* Create send and receive buffers */
2072 	rc = smc_buf_create(new_smc, true);
2073 	if (rc) {
2074 		smc_conn_abort(new_smc, ini->first_contact_local);
2075 		return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2076 					 SMC_CLC_DECL_MEM;
2077 	}
2078 
2079 	return 0;
2080 }
2081 
2082 static bool smc_is_already_selected(struct smcd_dev *smcd,
2083 				    struct smc_init_info *ini,
2084 				    int matches)
2085 {
2086 	int i;
2087 
2088 	for (i = 0; i < matches; i++)
2089 		if (smcd == ini->ism_dev[i])
2090 			return true;
2091 
2092 	return false;
2093 }
2094 
2095 /* check for ISM devices matching proposed ISM devices */
2096 static void smc_check_ism_v2_match(struct smc_init_info *ini,
2097 				   u16 proposed_chid,
2098 				   struct smcd_gid *proposed_gid,
2099 				   unsigned int *matches)
2100 {
2101 	struct smcd_dev *smcd;
2102 
2103 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2104 		if (smcd->going_away)
2105 			continue;
2106 		if (smc_is_already_selected(smcd, ini, *matches))
2107 			continue;
2108 		if (smc_ism_get_chid(smcd) == proposed_chid &&
2109 		    !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2110 			ini->ism_peer_gid[*matches].gid = proposed_gid->gid;
2111 			if (__smc_ism_is_emulated(proposed_chid))
2112 				ini->ism_peer_gid[*matches].gid_ext =
2113 							proposed_gid->gid_ext;
2114 				/* non-Emulated-ISM's peer gid_ext remains 0. */
2115 			ini->ism_dev[*matches] = smcd;
2116 			(*matches)++;
2117 			break;
2118 		}
2119 	}
2120 }
2121 
2122 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2123 {
2124 	if (!ini->rc)
2125 		ini->rc = rc;
2126 }
2127 
2128 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2129 					struct smc_clc_msg_proposal *pclc,
2130 					struct smc_init_info *ini)
2131 {
2132 	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2133 	struct smc_clc_v2_extension *smc_v2_ext;
2134 	struct smc_clc_msg_smcd *pclc_smcd;
2135 	unsigned int matches = 0;
2136 	struct smcd_gid smcd_gid;
2137 	u8 smcd_version;
2138 	u8 *eid = NULL;
2139 	int i, rc;
2140 	u16 chid;
2141 
2142 	if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2143 		goto not_found;
2144 
2145 	pclc_smcd = smc_get_clc_msg_smcd(pclc);
2146 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2147 	smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2148 
2149 	mutex_lock(&smcd_dev_list.mutex);
2150 	if (pclc_smcd->ism.chid) {
2151 		/* check for ISM device matching proposed native ISM device */
2152 		smcd_gid.gid = ntohll(pclc_smcd->ism.gid);
2153 		smcd_gid.gid_ext = 0;
2154 		smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2155 				       &smcd_gid, &matches);
2156 	}
2157 	for (i = 0; i < smc_v2_ext->hdr.ism_gid_cnt; i++) {
2158 		/* check for ISM devices matching proposed non-native ISM
2159 		 * devices
2160 		 */
2161 		smcd_gid.gid = ntohll(smcd_v2_ext->gidchid[i].gid);
2162 		smcd_gid.gid_ext = 0;
2163 		chid = ntohs(smcd_v2_ext->gidchid[i].chid);
2164 		if (__smc_ism_is_emulated(chid)) {
2165 			if ((i + 1) == smc_v2_ext->hdr.ism_gid_cnt ||
2166 			    chid != ntohs(smcd_v2_ext->gidchid[i + 1].chid))
2167 				/* each Emulated-ISM device takes two GID-CHID
2168 				 * entries and CHID of the second entry repeats
2169 				 * that of the first entry.
2170 				 *
2171 				 * So check if the next GID-CHID entry exists
2172 				 * and both two entries' CHIDs are the same.
2173 				 */
2174 				continue;
2175 			smcd_gid.gid_ext =
2176 				ntohll(smcd_v2_ext->gidchid[++i].gid);
2177 		}
2178 		smc_check_ism_v2_match(ini, chid, &smcd_gid, &matches);
2179 	}
2180 	mutex_unlock(&smcd_dev_list.mutex);
2181 
2182 	if (!ini->ism_dev[0]) {
2183 		smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2184 		goto not_found;
2185 	}
2186 
2187 	smc_ism_get_system_eid(&eid);
2188 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2189 			       smcd_v2_ext->system_eid, eid))
2190 		goto not_found;
2191 
2192 	/* separate - outside the smcd_dev_list.lock */
2193 	smcd_version = ini->smcd_version;
2194 	for (i = 0; i < matches; i++) {
2195 		ini->smcd_version = SMC_V2;
2196 		ini->is_smcd = true;
2197 		ini->ism_selected = i;
2198 		rc = smc_listen_ism_init(new_smc, ini);
2199 		if (rc) {
2200 			smc_find_ism_store_rc(rc, ini);
2201 			/* try next active ISM device */
2202 			continue;
2203 		}
2204 		return; /* matching and usable V2 ISM device found */
2205 	}
2206 	/* no V2 ISM device could be initialized */
2207 	ini->smcd_version = smcd_version;	/* restore original value */
2208 	ini->negotiated_eid[0] = 0;
2209 
2210 not_found:
2211 	ini->smcd_version &= ~SMC_V2;
2212 	ini->ism_dev[0] = NULL;
2213 	ini->is_smcd = false;
2214 }
2215 
2216 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2217 					struct smc_clc_msg_proposal *pclc,
2218 					struct smc_init_info *ini)
2219 {
2220 	struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2221 	int rc = 0;
2222 
2223 	/* check if ISM V1 is available */
2224 	if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2225 		goto not_found;
2226 	ini->is_smcd = true; /* prepare ISM check */
2227 	ini->ism_peer_gid[0].gid = ntohll(pclc_smcd->ism.gid);
2228 	ini->ism_peer_gid[0].gid_ext = 0;
2229 	rc = smc_find_ism_device(new_smc, ini);
2230 	if (rc)
2231 		goto not_found;
2232 	ini->ism_selected = 0;
2233 	rc = smc_listen_ism_init(new_smc, ini);
2234 	if (!rc)
2235 		return;		/* V1 ISM device found */
2236 
2237 not_found:
2238 	smc_find_ism_store_rc(rc, ini);
2239 	ini->smcd_version &= ~SMC_V1;
2240 	ini->ism_dev[0] = NULL;
2241 	ini->is_smcd = false;
2242 }
2243 
2244 /* listen worker: register buffers */
2245 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2246 {
2247 	struct smc_connection *conn = &new_smc->conn;
2248 
2249 	if (!local_first) {
2250 		/* reg sendbufs if they were vzalloced */
2251 		if (conn->sndbuf_desc->is_vm) {
2252 			if (smcr_lgr_reg_sndbufs(conn->lnk,
2253 						 conn->sndbuf_desc))
2254 				return SMC_CLC_DECL_ERR_REGBUF;
2255 		}
2256 		if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2257 			return SMC_CLC_DECL_ERR_REGBUF;
2258 	}
2259 
2260 	return 0;
2261 }
2262 
2263 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2264 					 struct smc_clc_msg_proposal *pclc,
2265 					 struct smc_init_info *ini)
2266 {
2267 	struct smc_clc_v2_extension *smc_v2_ext;
2268 	u8 smcr_version;
2269 	int rc;
2270 
2271 	if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2272 		goto not_found;
2273 
2274 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2275 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2276 		goto not_found;
2277 
2278 	/* prepare RDMA check */
2279 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2280 	memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2281 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2282 	ini->check_smcrv2 = true;
2283 	ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2284 	ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2285 	ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2286 	rc = smc_find_rdma_device(new_smc, ini);
2287 	if (rc) {
2288 		smc_find_ism_store_rc(rc, ini);
2289 		goto not_found;
2290 	}
2291 	if (!ini->smcrv2.uses_gateway)
2292 		memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2293 
2294 	smcr_version = ini->smcr_version;
2295 	ini->smcr_version = SMC_V2;
2296 	rc = smc_listen_rdma_init(new_smc, ini);
2297 	if (!rc) {
2298 		rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2299 		if (rc)
2300 			smc_conn_abort(new_smc, ini->first_contact_local);
2301 	}
2302 	if (!rc)
2303 		return;
2304 	ini->smcr_version = smcr_version;
2305 	smc_find_ism_store_rc(rc, ini);
2306 
2307 not_found:
2308 	ini->smcr_version &= ~SMC_V2;
2309 	ini->smcrv2.ib_dev_v2 = NULL;
2310 	ini->check_smcrv2 = false;
2311 }
2312 
2313 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2314 					struct smc_clc_msg_proposal *pclc,
2315 					struct smc_init_info *ini)
2316 {
2317 	int rc;
2318 
2319 	if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2320 		return SMC_CLC_DECL_NOSMCDEV;
2321 
2322 	/* prepare RDMA check */
2323 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2324 	memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2325 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2326 	rc = smc_find_rdma_device(new_smc, ini);
2327 	if (rc) {
2328 		/* no RDMA device found */
2329 		return SMC_CLC_DECL_NOSMCDEV;
2330 	}
2331 	rc = smc_listen_rdma_init(new_smc, ini);
2332 	if (rc)
2333 		return rc;
2334 	return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2335 }
2336 
2337 /* determine the local device matching to proposal */
2338 static int smc_listen_find_device(struct smc_sock *new_smc,
2339 				  struct smc_clc_msg_proposal *pclc,
2340 				  struct smc_init_info *ini)
2341 {
2342 	int prfx_rc;
2343 
2344 	/* check for ISM device matching V2 proposed device */
2345 	smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2346 	if (ini->ism_dev[0])
2347 		return 0;
2348 
2349 	/* check for matching IP prefix and subnet length (V1) */
2350 	prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2351 	if (prfx_rc)
2352 		smc_find_ism_store_rc(prfx_rc, ini);
2353 
2354 	/* get vlan id from IP device */
2355 	if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2356 		return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2357 
2358 	/* check for ISM device matching V1 proposed device */
2359 	if (!prfx_rc)
2360 		smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2361 	if (ini->ism_dev[0])
2362 		return 0;
2363 
2364 	if (!smcr_indicated(pclc->hdr.typev1) &&
2365 	    !smcr_indicated(pclc->hdr.typev2))
2366 		/* skip RDMA and decline */
2367 		return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2368 
2369 	/* check if RDMA V2 is available */
2370 	smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2371 	if (ini->smcrv2.ib_dev_v2)
2372 		return 0;
2373 
2374 	/* check if RDMA V1 is available */
2375 	if (!prfx_rc) {
2376 		int rc;
2377 
2378 		rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2379 		smc_find_ism_store_rc(rc, ini);
2380 		return (!rc) ? 0 : ini->rc;
2381 	}
2382 	return prfx_rc;
2383 }
2384 
2385 /* listen worker: finish RDMA setup */
2386 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2387 				  struct smc_clc_msg_accept_confirm *cclc,
2388 				  bool local_first,
2389 				  struct smc_init_info *ini)
2390 {
2391 	struct smc_link *link = new_smc->conn.lnk;
2392 	int reason_code = 0;
2393 
2394 	if (local_first)
2395 		smc_link_save_peer_info(link, cclc, ini);
2396 
2397 	if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2398 		return SMC_CLC_DECL_ERR_RTOK;
2399 
2400 	if (local_first) {
2401 		if (smc_ib_ready_link(link))
2402 			return SMC_CLC_DECL_ERR_RDYLNK;
2403 		/* QP confirmation over RoCE fabric */
2404 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2405 		reason_code = smcr_serv_conf_first_link(new_smc);
2406 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2407 	}
2408 	return reason_code;
2409 }
2410 
2411 /* setup for connection of server */
2412 static void smc_listen_work(struct work_struct *work)
2413 {
2414 	struct smc_sock *new_smc = container_of(work, struct smc_sock,
2415 						smc_listen_work);
2416 	struct socket *newclcsock = new_smc->clcsock;
2417 	struct smc_clc_msg_accept_confirm *cclc;
2418 	struct smc_clc_msg_proposal_area *buf;
2419 	struct smc_clc_msg_proposal *pclc;
2420 	struct smc_init_info *ini = NULL;
2421 	u8 proposal_version = SMC_V1;
2422 	u8 accept_version;
2423 	int rc = 0;
2424 
2425 	if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2426 		return smc_listen_out_err(new_smc);
2427 
2428 	if (new_smc->use_fallback) {
2429 		smc_listen_out_connected(new_smc);
2430 		return;
2431 	}
2432 
2433 	/* check if peer is smc capable */
2434 	if (!tcp_sk(newclcsock->sk)->syn_smc) {
2435 		rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2436 		if (rc)
2437 			smc_listen_out_err(new_smc);
2438 		else
2439 			smc_listen_out_connected(new_smc);
2440 		return;
2441 	}
2442 
2443 	/* do inband token exchange -
2444 	 * wait for and receive SMC Proposal CLC message
2445 	 */
2446 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2447 	if (!buf) {
2448 		rc = SMC_CLC_DECL_MEM;
2449 		goto out_decl;
2450 	}
2451 	pclc = (struct smc_clc_msg_proposal *)buf;
2452 	rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2453 			      SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2454 	if (rc)
2455 		goto out_decl;
2456 
2457 	if (pclc->hdr.version > SMC_V1)
2458 		proposal_version = SMC_V2;
2459 
2460 	/* IPSec connections opt out of SMC optimizations */
2461 	if (using_ipsec(new_smc)) {
2462 		rc = SMC_CLC_DECL_IPSEC;
2463 		goto out_decl;
2464 	}
2465 
2466 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2467 	if (!ini) {
2468 		rc = SMC_CLC_DECL_MEM;
2469 		goto out_decl;
2470 	}
2471 
2472 	/* initial version checking */
2473 	rc = smc_listen_v2_check(new_smc, pclc, ini);
2474 	if (rc)
2475 		goto out_decl;
2476 
2477 	rc = smc_clc_srv_v2x_features_validate(new_smc, pclc, ini);
2478 	if (rc)
2479 		goto out_decl;
2480 
2481 	mutex_lock(&smc_server_lgr_pending);
2482 	smc_close_init(new_smc);
2483 	smc_rx_init(new_smc);
2484 	smc_tx_init(new_smc);
2485 
2486 	/* determine ISM or RoCE device used for connection */
2487 	rc = smc_listen_find_device(new_smc, pclc, ini);
2488 	if (rc)
2489 		goto out_unlock;
2490 
2491 	/* send SMC Accept CLC message */
2492 	accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2493 	rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2494 				 accept_version, ini->negotiated_eid, ini);
2495 	if (rc)
2496 		goto out_unlock;
2497 
2498 	/* SMC-D does not need this lock any more */
2499 	if (ini->is_smcd)
2500 		mutex_unlock(&smc_server_lgr_pending);
2501 
2502 	/* receive SMC Confirm CLC message */
2503 	memset(buf, 0, sizeof(*buf));
2504 	cclc = (struct smc_clc_msg_accept_confirm *)buf;
2505 	rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2506 			      SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2507 	if (rc) {
2508 		if (!ini->is_smcd)
2509 			goto out_unlock;
2510 		goto out_decl;
2511 	}
2512 
2513 	rc = smc_clc_v2x_features_confirm_check(cclc, ini);
2514 	if (rc) {
2515 		if (!ini->is_smcd)
2516 			goto out_unlock;
2517 		goto out_decl;
2518 	}
2519 
2520 	/* fce smc release version is needed in smc_listen_rdma_finish,
2521 	 * so save fce info here.
2522 	 */
2523 	smc_conn_save_peer_info_fce(new_smc, cclc);
2524 
2525 	/* finish worker */
2526 	if (!ini->is_smcd) {
2527 		rc = smc_listen_rdma_finish(new_smc, cclc,
2528 					    ini->first_contact_local, ini);
2529 		if (rc)
2530 			goto out_unlock;
2531 		mutex_unlock(&smc_server_lgr_pending);
2532 	}
2533 	smc_conn_save_peer_info(new_smc, cclc);
2534 
2535 	if (ini->is_smcd &&
2536 	    smc_ism_support_dmb_nocopy(new_smc->conn.lgr->smcd)) {
2537 		rc = smcd_buf_attach(new_smc);
2538 		if (rc)
2539 			goto out_decl;
2540 	}
2541 
2542 	smc_listen_out_connected(new_smc);
2543 	SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2544 	goto out_free;
2545 
2546 out_unlock:
2547 	mutex_unlock(&smc_server_lgr_pending);
2548 out_decl:
2549 	smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2550 			   proposal_version);
2551 out_free:
2552 	kfree(ini);
2553 	kfree(buf);
2554 }
2555 
2556 static void smc_tcp_listen_work(struct work_struct *work)
2557 {
2558 	struct smc_sock *lsmc = container_of(work, struct smc_sock,
2559 					     tcp_listen_work);
2560 	struct sock *lsk = &lsmc->sk;
2561 	struct smc_sock *new_smc;
2562 	int rc = 0;
2563 
2564 	lock_sock(lsk);
2565 	while (lsk->sk_state == SMC_LISTEN) {
2566 		rc = smc_clcsock_accept(lsmc, &new_smc);
2567 		if (rc) /* clcsock accept queue empty or error */
2568 			goto out;
2569 		if (!new_smc)
2570 			continue;
2571 
2572 		if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2573 			atomic_inc(&lsmc->queued_smc_hs);
2574 
2575 		new_smc->listen_smc = lsmc;
2576 		new_smc->use_fallback = lsmc->use_fallback;
2577 		new_smc->fallback_rsn = lsmc->fallback_rsn;
2578 		sock_hold(lsk); /* sock_put in smc_listen_work */
2579 		INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2580 		smc_copy_sock_settings_to_smc(new_smc);
2581 		sock_hold(&new_smc->sk); /* sock_put in passive closing */
2582 		if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2583 			sock_put(&new_smc->sk);
2584 	}
2585 
2586 out:
2587 	release_sock(lsk);
2588 	sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2589 }
2590 
2591 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2592 {
2593 	struct smc_sock *lsmc;
2594 
2595 	read_lock_bh(&listen_clcsock->sk_callback_lock);
2596 	lsmc = smc_clcsock_user_data(listen_clcsock);
2597 	if (!lsmc)
2598 		goto out;
2599 	lsmc->clcsk_data_ready(listen_clcsock);
2600 	if (lsmc->sk.sk_state == SMC_LISTEN) {
2601 		sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2602 		if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2603 			sock_put(&lsmc->sk);
2604 	}
2605 out:
2606 	read_unlock_bh(&listen_clcsock->sk_callback_lock);
2607 }
2608 
2609 int smc_listen(struct socket *sock, int backlog)
2610 {
2611 	struct sock *sk = sock->sk;
2612 	struct smc_sock *smc;
2613 	int rc;
2614 
2615 	smc = smc_sk(sk);
2616 	lock_sock(sk);
2617 
2618 	rc = -EINVAL;
2619 	if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2620 	    smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2621 		goto out;
2622 
2623 	rc = 0;
2624 	if (sk->sk_state == SMC_LISTEN) {
2625 		sk->sk_max_ack_backlog = backlog;
2626 		goto out;
2627 	}
2628 	/* some socket options are handled in core, so we could not apply
2629 	 * them to the clc socket -- copy smc socket options to clc socket
2630 	 */
2631 	smc_copy_sock_settings_to_clc(smc);
2632 	if (!smc->use_fallback)
2633 		tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2634 
2635 	/* save original sk_data_ready function and establish
2636 	 * smc-specific sk_data_ready function
2637 	 */
2638 	write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2639 	smc->clcsock->sk->sk_user_data =
2640 		(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2641 	smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2642 			       smc_clcsock_data_ready, &smc->clcsk_data_ready);
2643 	write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2644 
2645 	/* save original ops */
2646 	smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2647 
2648 	smc->af_ops = *smc->ori_af_ops;
2649 	smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2650 
2651 	inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2652 
2653 	if (smc->limit_smc_hs)
2654 		tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2655 
2656 	rc = kernel_listen(smc->clcsock, backlog);
2657 	if (rc) {
2658 		write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2659 		smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2660 				       &smc->clcsk_data_ready);
2661 		smc->clcsock->sk->sk_user_data = NULL;
2662 		write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2663 		goto out;
2664 	}
2665 	sk->sk_max_ack_backlog = backlog;
2666 	sk->sk_ack_backlog = 0;
2667 	sk->sk_state = SMC_LISTEN;
2668 
2669 out:
2670 	release_sock(sk);
2671 	return rc;
2672 }
2673 
2674 int smc_accept(struct socket *sock, struct socket *new_sock,
2675 	       struct proto_accept_arg *arg)
2676 {
2677 	struct sock *sk = sock->sk, *nsk;
2678 	DECLARE_WAITQUEUE(wait, current);
2679 	struct smc_sock *lsmc;
2680 	long timeo;
2681 	int rc = 0;
2682 
2683 	lsmc = smc_sk(sk);
2684 	sock_hold(sk); /* sock_put below */
2685 	lock_sock(sk);
2686 
2687 	if (lsmc->sk.sk_state != SMC_LISTEN) {
2688 		rc = -EINVAL;
2689 		release_sock(sk);
2690 		goto out;
2691 	}
2692 
2693 	/* Wait for an incoming connection */
2694 	timeo = sock_rcvtimeo(sk, arg->flags & O_NONBLOCK);
2695 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
2696 	while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2697 		set_current_state(TASK_INTERRUPTIBLE);
2698 		if (!timeo) {
2699 			rc = -EAGAIN;
2700 			break;
2701 		}
2702 		release_sock(sk);
2703 		timeo = schedule_timeout(timeo);
2704 		/* wakeup by sk_data_ready in smc_listen_work() */
2705 		sched_annotate_sleep();
2706 		lock_sock(sk);
2707 		if (signal_pending(current)) {
2708 			rc = sock_intr_errno(timeo);
2709 			break;
2710 		}
2711 	}
2712 	set_current_state(TASK_RUNNING);
2713 	remove_wait_queue(sk_sleep(sk), &wait);
2714 
2715 	if (!rc)
2716 		rc = sock_error(nsk);
2717 	release_sock(sk);
2718 	if (rc)
2719 		goto out;
2720 
2721 	if (lsmc->sockopt_defer_accept && !(arg->flags & O_NONBLOCK)) {
2722 		/* wait till data arrives on the socket */
2723 		timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2724 								MSEC_PER_SEC);
2725 		if (smc_sk(nsk)->use_fallback) {
2726 			struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2727 
2728 			lock_sock(clcsk);
2729 			if (skb_queue_empty(&clcsk->sk_receive_queue))
2730 				sk_wait_data(clcsk, &timeo, NULL);
2731 			release_sock(clcsk);
2732 		} else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2733 			lock_sock(nsk);
2734 			smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2735 			release_sock(nsk);
2736 		}
2737 	}
2738 
2739 out:
2740 	sock_put(sk); /* sock_hold above */
2741 	return rc;
2742 }
2743 
2744 int smc_getname(struct socket *sock, struct sockaddr *addr,
2745 		int peer)
2746 {
2747 	struct smc_sock *smc;
2748 
2749 	if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2750 	    (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2751 		return -ENOTCONN;
2752 
2753 	smc = smc_sk(sock->sk);
2754 
2755 	return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2756 }
2757 
2758 int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2759 {
2760 	struct sock *sk = sock->sk;
2761 	struct smc_sock *smc;
2762 	int rc;
2763 
2764 	smc = smc_sk(sk);
2765 	lock_sock(sk);
2766 
2767 	/* SMC does not support connect with fastopen */
2768 	if (msg->msg_flags & MSG_FASTOPEN) {
2769 		/* not connected yet, fallback */
2770 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2771 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2772 			if (rc)
2773 				goto out;
2774 		} else {
2775 			rc = -EINVAL;
2776 			goto out;
2777 		}
2778 	} else if ((sk->sk_state != SMC_ACTIVE) &&
2779 		   (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2780 		   (sk->sk_state != SMC_INIT)) {
2781 		rc = -EPIPE;
2782 		goto out;
2783 	}
2784 
2785 	if (smc->use_fallback) {
2786 		rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2787 	} else {
2788 		rc = smc_tx_sendmsg(smc, msg, len);
2789 		SMC_STAT_TX_PAYLOAD(smc, len, rc);
2790 	}
2791 out:
2792 	release_sock(sk);
2793 	return rc;
2794 }
2795 
2796 int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2797 		int flags)
2798 {
2799 	struct sock *sk = sock->sk;
2800 	struct smc_sock *smc;
2801 	int rc = -ENOTCONN;
2802 
2803 	smc = smc_sk(sk);
2804 	lock_sock(sk);
2805 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2806 		/* socket was connected before, no more data to read */
2807 		rc = 0;
2808 		goto out;
2809 	}
2810 	if ((sk->sk_state == SMC_INIT) ||
2811 	    (sk->sk_state == SMC_LISTEN) ||
2812 	    (sk->sk_state == SMC_CLOSED))
2813 		goto out;
2814 
2815 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2816 		rc = 0;
2817 		goto out;
2818 	}
2819 
2820 	if (smc->use_fallback) {
2821 		rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2822 	} else {
2823 		msg->msg_namelen = 0;
2824 		rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2825 		SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2826 	}
2827 
2828 out:
2829 	release_sock(sk);
2830 	return rc;
2831 }
2832 
2833 static __poll_t smc_accept_poll(struct sock *parent)
2834 {
2835 	struct smc_sock *isk = smc_sk(parent);
2836 	__poll_t mask = 0;
2837 
2838 	spin_lock(&isk->accept_q_lock);
2839 	if (!list_empty(&isk->accept_q))
2840 		mask = EPOLLIN | EPOLLRDNORM;
2841 	spin_unlock(&isk->accept_q_lock);
2842 
2843 	return mask;
2844 }
2845 
2846 __poll_t smc_poll(struct file *file, struct socket *sock,
2847 		  poll_table *wait)
2848 {
2849 	struct sock *sk = sock->sk;
2850 	struct smc_sock *smc;
2851 	__poll_t mask = 0;
2852 
2853 	if (!sk)
2854 		return EPOLLNVAL;
2855 
2856 	smc = smc_sk(sock->sk);
2857 	if (smc->use_fallback) {
2858 		/* delegate to CLC child sock */
2859 		mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2860 		sk->sk_err = smc->clcsock->sk->sk_err;
2861 	} else {
2862 		if (sk->sk_state != SMC_CLOSED)
2863 			sock_poll_wait(file, sock, wait);
2864 		if (sk->sk_err)
2865 			mask |= EPOLLERR;
2866 		if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2867 		    (sk->sk_state == SMC_CLOSED))
2868 			mask |= EPOLLHUP;
2869 		if (sk->sk_state == SMC_LISTEN) {
2870 			/* woken up by sk_data_ready in smc_listen_work() */
2871 			mask |= smc_accept_poll(sk);
2872 		} else if (smc->use_fallback) { /* as result of connect_work()*/
2873 			mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2874 							   wait);
2875 			sk->sk_err = smc->clcsock->sk->sk_err;
2876 		} else {
2877 			if ((sk->sk_state != SMC_INIT &&
2878 			     atomic_read(&smc->conn.sndbuf_space)) ||
2879 			    sk->sk_shutdown & SEND_SHUTDOWN) {
2880 				mask |= EPOLLOUT | EPOLLWRNORM;
2881 			} else {
2882 				sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2883 				set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2884 			}
2885 			if (atomic_read(&smc->conn.bytes_to_rcv))
2886 				mask |= EPOLLIN | EPOLLRDNORM;
2887 			if (sk->sk_shutdown & RCV_SHUTDOWN)
2888 				mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2889 			if (sk->sk_state == SMC_APPCLOSEWAIT1)
2890 				mask |= EPOLLIN;
2891 			if (smc->conn.urg_state == SMC_URG_VALID)
2892 				mask |= EPOLLPRI;
2893 		}
2894 	}
2895 
2896 	return mask;
2897 }
2898 
2899 int smc_shutdown(struct socket *sock, int how)
2900 {
2901 	struct sock *sk = sock->sk;
2902 	bool do_shutdown = true;
2903 	struct smc_sock *smc;
2904 	int rc = -EINVAL;
2905 	int old_state;
2906 	int rc1 = 0;
2907 
2908 	smc = smc_sk(sk);
2909 
2910 	if ((how < SHUT_RD) || (how > SHUT_RDWR))
2911 		return rc;
2912 
2913 	lock_sock(sk);
2914 
2915 	if (sock->state == SS_CONNECTING) {
2916 		if (sk->sk_state == SMC_ACTIVE)
2917 			sock->state = SS_CONNECTED;
2918 		else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2919 			 sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2920 			 sk->sk_state == SMC_APPCLOSEWAIT1 ||
2921 			 sk->sk_state == SMC_APPCLOSEWAIT2 ||
2922 			 sk->sk_state == SMC_APPFINCLOSEWAIT)
2923 			sock->state = SS_DISCONNECTING;
2924 	}
2925 
2926 	rc = -ENOTCONN;
2927 	if ((sk->sk_state != SMC_ACTIVE) &&
2928 	    (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2929 	    (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2930 	    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2931 	    (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2932 	    (sk->sk_state != SMC_APPFINCLOSEWAIT))
2933 		goto out;
2934 	if (smc->use_fallback) {
2935 		rc = kernel_sock_shutdown(smc->clcsock, how);
2936 		sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2937 		if (sk->sk_shutdown == SHUTDOWN_MASK) {
2938 			sk->sk_state = SMC_CLOSED;
2939 			sk->sk_socket->state = SS_UNCONNECTED;
2940 			sock_put(sk);
2941 		}
2942 		goto out;
2943 	}
2944 	switch (how) {
2945 	case SHUT_RDWR:		/* shutdown in both directions */
2946 		old_state = sk->sk_state;
2947 		rc = smc_close_active(smc);
2948 		if (old_state == SMC_ACTIVE &&
2949 		    sk->sk_state == SMC_PEERCLOSEWAIT1)
2950 			do_shutdown = false;
2951 		break;
2952 	case SHUT_WR:
2953 		rc = smc_close_shutdown_write(smc);
2954 		break;
2955 	case SHUT_RD:
2956 		rc = 0;
2957 		/* nothing more to do because peer is not involved */
2958 		break;
2959 	}
2960 	if (do_shutdown && smc->clcsock)
2961 		rc1 = kernel_sock_shutdown(smc->clcsock, how);
2962 	/* map sock_shutdown_cmd constants to sk_shutdown value range */
2963 	sk->sk_shutdown |= how + 1;
2964 
2965 	if (sk->sk_state == SMC_CLOSED)
2966 		sock->state = SS_UNCONNECTED;
2967 	else
2968 		sock->state = SS_DISCONNECTING;
2969 out:
2970 	release_sock(sk);
2971 	return rc ? rc : rc1;
2972 }
2973 
2974 static int __smc_getsockopt(struct socket *sock, int level, int optname,
2975 			    char __user *optval, int __user *optlen)
2976 {
2977 	struct smc_sock *smc;
2978 	int val, len;
2979 
2980 	smc = smc_sk(sock->sk);
2981 
2982 	if (get_user(len, optlen))
2983 		return -EFAULT;
2984 
2985 	len = min_t(int, len, sizeof(int));
2986 
2987 	if (len < 0)
2988 		return -EINVAL;
2989 
2990 	switch (optname) {
2991 	case SMC_LIMIT_HS:
2992 		val = smc->limit_smc_hs;
2993 		break;
2994 	default:
2995 		return -EOPNOTSUPP;
2996 	}
2997 
2998 	if (put_user(len, optlen))
2999 		return -EFAULT;
3000 	if (copy_to_user(optval, &val, len))
3001 		return -EFAULT;
3002 
3003 	return 0;
3004 }
3005 
3006 static int __smc_setsockopt(struct socket *sock, int level, int optname,
3007 			    sockptr_t optval, unsigned int optlen)
3008 {
3009 	struct sock *sk = sock->sk;
3010 	struct smc_sock *smc;
3011 	int val, rc;
3012 
3013 	smc = smc_sk(sk);
3014 
3015 	lock_sock(sk);
3016 	switch (optname) {
3017 	case SMC_LIMIT_HS:
3018 		if (optlen < sizeof(int)) {
3019 			rc = -EINVAL;
3020 			break;
3021 		}
3022 		if (copy_from_sockptr(&val, optval, sizeof(int))) {
3023 			rc = -EFAULT;
3024 			break;
3025 		}
3026 
3027 		smc->limit_smc_hs = !!val;
3028 		rc = 0;
3029 		break;
3030 	default:
3031 		rc = -EOPNOTSUPP;
3032 		break;
3033 	}
3034 	release_sock(sk);
3035 
3036 	return rc;
3037 }
3038 
3039 int smc_setsockopt(struct socket *sock, int level, int optname,
3040 		   sockptr_t optval, unsigned int optlen)
3041 {
3042 	struct sock *sk = sock->sk;
3043 	struct smc_sock *smc;
3044 	int val, rc;
3045 
3046 	if (level == SOL_TCP && optname == TCP_ULP)
3047 		return -EOPNOTSUPP;
3048 	else if (level == SOL_SMC)
3049 		return __smc_setsockopt(sock, level, optname, optval, optlen);
3050 
3051 	smc = smc_sk(sk);
3052 
3053 	/* generic setsockopts reaching us here always apply to the
3054 	 * CLC socket
3055 	 */
3056 	mutex_lock(&smc->clcsock_release_lock);
3057 	if (!smc->clcsock) {
3058 		mutex_unlock(&smc->clcsock_release_lock);
3059 		return -EBADF;
3060 	}
3061 	if (unlikely(!smc->clcsock->ops->setsockopt))
3062 		rc = -EOPNOTSUPP;
3063 	else
3064 		rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
3065 						   optval, optlen);
3066 	if (smc->clcsock->sk->sk_err) {
3067 		sk->sk_err = smc->clcsock->sk->sk_err;
3068 		sk_error_report(sk);
3069 	}
3070 	mutex_unlock(&smc->clcsock_release_lock);
3071 
3072 	if (optlen < sizeof(int))
3073 		return -EINVAL;
3074 	if (copy_from_sockptr(&val, optval, sizeof(int)))
3075 		return -EFAULT;
3076 
3077 	lock_sock(sk);
3078 	if (rc || smc->use_fallback)
3079 		goto out;
3080 	switch (optname) {
3081 	case TCP_FASTOPEN:
3082 	case TCP_FASTOPEN_CONNECT:
3083 	case TCP_FASTOPEN_KEY:
3084 	case TCP_FASTOPEN_NO_COOKIE:
3085 		/* option not supported by SMC */
3086 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
3087 			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
3088 		} else {
3089 			rc = -EINVAL;
3090 		}
3091 		break;
3092 	case TCP_NODELAY:
3093 		if (sk->sk_state != SMC_INIT &&
3094 		    sk->sk_state != SMC_LISTEN &&
3095 		    sk->sk_state != SMC_CLOSED) {
3096 			if (val) {
3097 				SMC_STAT_INC(smc, ndly_cnt);
3098 				smc_tx_pending(&smc->conn);
3099 				cancel_delayed_work(&smc->conn.tx_work);
3100 			}
3101 		}
3102 		break;
3103 	case TCP_CORK:
3104 		if (sk->sk_state != SMC_INIT &&
3105 		    sk->sk_state != SMC_LISTEN &&
3106 		    sk->sk_state != SMC_CLOSED) {
3107 			if (!val) {
3108 				SMC_STAT_INC(smc, cork_cnt);
3109 				smc_tx_pending(&smc->conn);
3110 				cancel_delayed_work(&smc->conn.tx_work);
3111 			}
3112 		}
3113 		break;
3114 	case TCP_DEFER_ACCEPT:
3115 		smc->sockopt_defer_accept = val;
3116 		break;
3117 	default:
3118 		break;
3119 	}
3120 out:
3121 	release_sock(sk);
3122 
3123 	return rc;
3124 }
3125 
3126 int smc_getsockopt(struct socket *sock, int level, int optname,
3127 		   char __user *optval, int __user *optlen)
3128 {
3129 	struct smc_sock *smc;
3130 	int rc;
3131 
3132 	if (level == SOL_SMC)
3133 		return __smc_getsockopt(sock, level, optname, optval, optlen);
3134 
3135 	smc = smc_sk(sock->sk);
3136 	mutex_lock(&smc->clcsock_release_lock);
3137 	if (!smc->clcsock) {
3138 		mutex_unlock(&smc->clcsock_release_lock);
3139 		return -EBADF;
3140 	}
3141 	/* socket options apply to the CLC socket */
3142 	if (unlikely(!smc->clcsock->ops->getsockopt)) {
3143 		mutex_unlock(&smc->clcsock_release_lock);
3144 		return -EOPNOTSUPP;
3145 	}
3146 	rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3147 					   optval, optlen);
3148 	mutex_unlock(&smc->clcsock_release_lock);
3149 	return rc;
3150 }
3151 
3152 int smc_ioctl(struct socket *sock, unsigned int cmd,
3153 	      unsigned long arg)
3154 {
3155 	union smc_host_cursor cons, urg;
3156 	struct smc_connection *conn;
3157 	struct smc_sock *smc;
3158 	int answ;
3159 
3160 	smc = smc_sk(sock->sk);
3161 	conn = &smc->conn;
3162 	lock_sock(&smc->sk);
3163 	if (smc->use_fallback) {
3164 		if (!smc->clcsock) {
3165 			release_sock(&smc->sk);
3166 			return -EBADF;
3167 		}
3168 		answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3169 		release_sock(&smc->sk);
3170 		return answ;
3171 	}
3172 	switch (cmd) {
3173 	case SIOCINQ: /* same as FIONREAD */
3174 		if (smc->sk.sk_state == SMC_LISTEN) {
3175 			release_sock(&smc->sk);
3176 			return -EINVAL;
3177 		}
3178 		if (smc->sk.sk_state == SMC_INIT ||
3179 		    smc->sk.sk_state == SMC_CLOSED)
3180 			answ = 0;
3181 		else
3182 			answ = atomic_read(&smc->conn.bytes_to_rcv);
3183 		break;
3184 	case SIOCOUTQ:
3185 		/* output queue size (not send + not acked) */
3186 		if (smc->sk.sk_state == SMC_LISTEN) {
3187 			release_sock(&smc->sk);
3188 			return -EINVAL;
3189 		}
3190 		if (smc->sk.sk_state == SMC_INIT ||
3191 		    smc->sk.sk_state == SMC_CLOSED)
3192 			answ = 0;
3193 		else
3194 			answ = smc->conn.sndbuf_desc->len -
3195 					atomic_read(&smc->conn.sndbuf_space);
3196 		break;
3197 	case SIOCOUTQNSD:
3198 		/* output queue size (not send only) */
3199 		if (smc->sk.sk_state == SMC_LISTEN) {
3200 			release_sock(&smc->sk);
3201 			return -EINVAL;
3202 		}
3203 		if (smc->sk.sk_state == SMC_INIT ||
3204 		    smc->sk.sk_state == SMC_CLOSED)
3205 			answ = 0;
3206 		else
3207 			answ = smc_tx_prepared_sends(&smc->conn);
3208 		break;
3209 	case SIOCATMARK:
3210 		if (smc->sk.sk_state == SMC_LISTEN) {
3211 			release_sock(&smc->sk);
3212 			return -EINVAL;
3213 		}
3214 		if (smc->sk.sk_state == SMC_INIT ||
3215 		    smc->sk.sk_state == SMC_CLOSED) {
3216 			answ = 0;
3217 		} else {
3218 			smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3219 			smc_curs_copy(&urg, &conn->urg_curs, conn);
3220 			answ = smc_curs_diff(conn->rmb_desc->len,
3221 					     &cons, &urg) == 1;
3222 		}
3223 		break;
3224 	default:
3225 		release_sock(&smc->sk);
3226 		return -ENOIOCTLCMD;
3227 	}
3228 	release_sock(&smc->sk);
3229 
3230 	return put_user(answ, (int __user *)arg);
3231 }
3232 
3233 /* Map the affected portions of the rmbe into an spd, note the number of bytes
3234  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3235  * updates till whenever a respective page has been fully processed.
3236  * Note that subsequent recv() calls have to wait till all splice() processing
3237  * completed.
3238  */
3239 ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3240 			struct pipe_inode_info *pipe, size_t len,
3241 			unsigned int flags)
3242 {
3243 	struct sock *sk = sock->sk;
3244 	struct smc_sock *smc;
3245 	int rc = -ENOTCONN;
3246 
3247 	smc = smc_sk(sk);
3248 	lock_sock(sk);
3249 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3250 		/* socket was connected before, no more data to read */
3251 		rc = 0;
3252 		goto out;
3253 	}
3254 	if (sk->sk_state == SMC_INIT ||
3255 	    sk->sk_state == SMC_LISTEN ||
3256 	    sk->sk_state == SMC_CLOSED)
3257 		goto out;
3258 
3259 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3260 		rc = 0;
3261 		goto out;
3262 	}
3263 
3264 	if (smc->use_fallback) {
3265 		rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3266 						    pipe, len, flags);
3267 	} else {
3268 		if (*ppos) {
3269 			rc = -ESPIPE;
3270 			goto out;
3271 		}
3272 		if (flags & SPLICE_F_NONBLOCK)
3273 			flags = MSG_DONTWAIT;
3274 		else
3275 			flags = 0;
3276 		SMC_STAT_INC(smc, splice_cnt);
3277 		rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3278 	}
3279 out:
3280 	release_sock(sk);
3281 
3282 	return rc;
3283 }
3284 
3285 /* must look like tcp */
3286 static const struct proto_ops smc_sock_ops = {
3287 	.family		= PF_SMC,
3288 	.owner		= THIS_MODULE,
3289 	.release	= smc_release,
3290 	.bind		= smc_bind,
3291 	.connect	= smc_connect,
3292 	.socketpair	= sock_no_socketpair,
3293 	.accept		= smc_accept,
3294 	.getname	= smc_getname,
3295 	.poll		= smc_poll,
3296 	.ioctl		= smc_ioctl,
3297 	.listen		= smc_listen,
3298 	.shutdown	= smc_shutdown,
3299 	.setsockopt	= smc_setsockopt,
3300 	.getsockopt	= smc_getsockopt,
3301 	.sendmsg	= smc_sendmsg,
3302 	.recvmsg	= smc_recvmsg,
3303 	.mmap		= sock_no_mmap,
3304 	.splice_read	= smc_splice_read,
3305 };
3306 
3307 int smc_create_clcsk(struct net *net, struct sock *sk, int family)
3308 {
3309 	struct smc_sock *smc = smc_sk(sk);
3310 	int rc;
3311 
3312 	rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3313 			      &smc->clcsock);
3314 	if (rc)
3315 		return rc;
3316 
3317 	/* smc_clcsock_release() does not wait smc->clcsock->sk's
3318 	 * destruction;  its sk_state might not be TCP_CLOSE after
3319 	 * smc->sk is close()d, and TCP timers can be fired later,
3320 	 * which need net ref.
3321 	 */
3322 	sk = smc->clcsock->sk;
3323 	__netns_tracker_free(net, &sk->ns_tracker, false);
3324 	sk->sk_net_refcnt = 1;
3325 	get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
3326 	sock_inuse_add(net, 1);
3327 	return 0;
3328 }
3329 
3330 static int __smc_create(struct net *net, struct socket *sock, int protocol,
3331 			int kern, struct socket *clcsock)
3332 {
3333 	int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3334 	struct smc_sock *smc;
3335 	struct sock *sk;
3336 	int rc;
3337 
3338 	rc = -ESOCKTNOSUPPORT;
3339 	if (sock->type != SOCK_STREAM)
3340 		goto out;
3341 
3342 	rc = -EPROTONOSUPPORT;
3343 	if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3344 		goto out;
3345 
3346 	rc = -ENOBUFS;
3347 	sock->ops = &smc_sock_ops;
3348 	sock->state = SS_UNCONNECTED;
3349 	sk = smc_sock_alloc(net, sock, protocol);
3350 	if (!sk)
3351 		goto out;
3352 
3353 	/* create internal TCP socket for CLC handshake and fallback */
3354 	smc = smc_sk(sk);
3355 
3356 	rc = 0;
3357 	if (clcsock)
3358 		smc->clcsock = clcsock;
3359 	else
3360 		rc = smc_create_clcsk(net, sk, family);
3361 
3362 	if (rc) {
3363 		sk_common_release(sk);
3364 		sock->sk = NULL;
3365 	}
3366 out:
3367 	return rc;
3368 }
3369 
3370 static int smc_create(struct net *net, struct socket *sock, int protocol,
3371 		      int kern)
3372 {
3373 	return __smc_create(net, sock, protocol, kern, NULL);
3374 }
3375 
3376 static const struct net_proto_family smc_sock_family_ops = {
3377 	.family	= PF_SMC,
3378 	.owner	= THIS_MODULE,
3379 	.create	= smc_create,
3380 };
3381 
3382 static int smc_ulp_init(struct sock *sk)
3383 {
3384 	struct socket *tcp = sk->sk_socket;
3385 	struct net *net = sock_net(sk);
3386 	struct socket *smcsock;
3387 	int protocol, ret;
3388 
3389 	/* only TCP can be replaced */
3390 	if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3391 	    (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3392 		return -ESOCKTNOSUPPORT;
3393 	/* don't handle wq now */
3394 	if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3395 		return -ENOTCONN;
3396 
3397 	if (sk->sk_family == AF_INET)
3398 		protocol = SMCPROTO_SMC;
3399 	else
3400 		protocol = SMCPROTO_SMC6;
3401 
3402 	smcsock = sock_alloc();
3403 	if (!smcsock)
3404 		return -ENFILE;
3405 
3406 	smcsock->type = SOCK_STREAM;
3407 	__module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3408 	ret = __smc_create(net, smcsock, protocol, 1, tcp);
3409 	if (ret) {
3410 		sock_release(smcsock); /* module_put() which ops won't be NULL */
3411 		return ret;
3412 	}
3413 
3414 	/* replace tcp socket to smc */
3415 	smcsock->file = tcp->file;
3416 	smcsock->file->private_data = smcsock;
3417 	smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3418 	smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3419 	tcp->file = NULL;
3420 
3421 	return ret;
3422 }
3423 
3424 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3425 			  const gfp_t priority)
3426 {
3427 	struct inet_connection_sock *icsk = inet_csk(newsk);
3428 
3429 	/* don't inherit ulp ops to child when listen */
3430 	icsk->icsk_ulp_ops = NULL;
3431 }
3432 
3433 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3434 	.name		= "smc",
3435 	.owner		= THIS_MODULE,
3436 	.init		= smc_ulp_init,
3437 	.clone		= smc_ulp_clone,
3438 };
3439 
3440 unsigned int smc_net_id;
3441 
3442 static __net_init int smc_net_init(struct net *net)
3443 {
3444 	int rc;
3445 
3446 	rc = smc_sysctl_net_init(net);
3447 	if (rc)
3448 		return rc;
3449 	return smc_pnet_net_init(net);
3450 }
3451 
3452 static void __net_exit smc_net_exit(struct net *net)
3453 {
3454 	smc_sysctl_net_exit(net);
3455 	smc_pnet_net_exit(net);
3456 }
3457 
3458 static __net_init int smc_net_stat_init(struct net *net)
3459 {
3460 	return smc_stats_init(net);
3461 }
3462 
3463 static void __net_exit smc_net_stat_exit(struct net *net)
3464 {
3465 	smc_stats_exit(net);
3466 }
3467 
3468 static struct pernet_operations smc_net_ops = {
3469 	.init = smc_net_init,
3470 	.exit = smc_net_exit,
3471 	.id   = &smc_net_id,
3472 	.size = sizeof(struct smc_net),
3473 };
3474 
3475 static struct pernet_operations smc_net_stat_ops = {
3476 	.init = smc_net_stat_init,
3477 	.exit = smc_net_stat_exit,
3478 };
3479 
3480 static int __init smc_init(void)
3481 {
3482 	int rc;
3483 
3484 	rc = register_pernet_subsys(&smc_net_ops);
3485 	if (rc)
3486 		return rc;
3487 
3488 	rc = register_pernet_subsys(&smc_net_stat_ops);
3489 	if (rc)
3490 		goto out_pernet_subsys;
3491 
3492 	rc = smc_ism_init();
3493 	if (rc)
3494 		goto out_pernet_subsys_stat;
3495 	smc_clc_init();
3496 
3497 	rc = smc_nl_init();
3498 	if (rc)
3499 		goto out_ism;
3500 
3501 	rc = smc_pnet_init();
3502 	if (rc)
3503 		goto out_nl;
3504 
3505 	rc = -ENOMEM;
3506 
3507 	smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3508 	if (!smc_tcp_ls_wq)
3509 		goto out_pnet;
3510 
3511 	smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3512 	if (!smc_hs_wq)
3513 		goto out_alloc_tcp_ls_wq;
3514 
3515 	smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3516 	if (!smc_close_wq)
3517 		goto out_alloc_hs_wq;
3518 
3519 	rc = smc_core_init();
3520 	if (rc) {
3521 		pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3522 		goto out_alloc_wqs;
3523 	}
3524 
3525 	rc = smc_llc_init();
3526 	if (rc) {
3527 		pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3528 		goto out_core;
3529 	}
3530 
3531 	rc = smc_cdc_init();
3532 	if (rc) {
3533 		pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3534 		goto out_core;
3535 	}
3536 
3537 	rc = proto_register(&smc_proto, 1);
3538 	if (rc) {
3539 		pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3540 		goto out_core;
3541 	}
3542 
3543 	rc = proto_register(&smc_proto6, 1);
3544 	if (rc) {
3545 		pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3546 		goto out_proto;
3547 	}
3548 
3549 	rc = sock_register(&smc_sock_family_ops);
3550 	if (rc) {
3551 		pr_err("%s: sock_register fails with %d\n", __func__, rc);
3552 		goto out_proto6;
3553 	}
3554 	INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3555 	INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3556 
3557 	rc = smc_ib_register_client();
3558 	if (rc) {
3559 		pr_err("%s: ib_register fails with %d\n", __func__, rc);
3560 		goto out_sock;
3561 	}
3562 
3563 	rc = smc_loopback_init();
3564 	if (rc) {
3565 		pr_err("%s: smc_loopback_init fails with %d\n", __func__, rc);
3566 		goto out_ib;
3567 	}
3568 
3569 	rc = tcp_register_ulp(&smc_ulp_ops);
3570 	if (rc) {
3571 		pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3572 		goto out_lo;
3573 	}
3574 	rc = smc_inet_init();
3575 	if (rc) {
3576 		pr_err("%s: smc_inet_init fails with %d\n", __func__, rc);
3577 		goto out_ulp;
3578 	}
3579 	static_branch_enable(&tcp_have_smc);
3580 	return 0;
3581 out_ulp:
3582 	tcp_unregister_ulp(&smc_ulp_ops);
3583 out_lo:
3584 	smc_loopback_exit();
3585 out_ib:
3586 	smc_ib_unregister_client();
3587 out_sock:
3588 	sock_unregister(PF_SMC);
3589 out_proto6:
3590 	proto_unregister(&smc_proto6);
3591 out_proto:
3592 	proto_unregister(&smc_proto);
3593 out_core:
3594 	smc_core_exit();
3595 out_alloc_wqs:
3596 	destroy_workqueue(smc_close_wq);
3597 out_alloc_hs_wq:
3598 	destroy_workqueue(smc_hs_wq);
3599 out_alloc_tcp_ls_wq:
3600 	destroy_workqueue(smc_tcp_ls_wq);
3601 out_pnet:
3602 	smc_pnet_exit();
3603 out_nl:
3604 	smc_nl_exit();
3605 out_ism:
3606 	smc_clc_exit();
3607 	smc_ism_exit();
3608 out_pernet_subsys_stat:
3609 	unregister_pernet_subsys(&smc_net_stat_ops);
3610 out_pernet_subsys:
3611 	unregister_pernet_subsys(&smc_net_ops);
3612 
3613 	return rc;
3614 }
3615 
3616 static void __exit smc_exit(void)
3617 {
3618 	static_branch_disable(&tcp_have_smc);
3619 	smc_inet_exit();
3620 	tcp_unregister_ulp(&smc_ulp_ops);
3621 	sock_unregister(PF_SMC);
3622 	smc_core_exit();
3623 	smc_loopback_exit();
3624 	smc_ib_unregister_client();
3625 	smc_ism_exit();
3626 	destroy_workqueue(smc_close_wq);
3627 	destroy_workqueue(smc_tcp_ls_wq);
3628 	destroy_workqueue(smc_hs_wq);
3629 	proto_unregister(&smc_proto6);
3630 	proto_unregister(&smc_proto);
3631 	smc_pnet_exit();
3632 	smc_nl_exit();
3633 	smc_clc_exit();
3634 	unregister_pernet_subsys(&smc_net_stat_ops);
3635 	unregister_pernet_subsys(&smc_net_ops);
3636 	rcu_barrier();
3637 }
3638 
3639 module_init(smc_init);
3640 module_exit(smc_exit);
3641 
3642 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3643 MODULE_DESCRIPTION("smc socket address family");
3644 MODULE_LICENSE("GPL");
3645 MODULE_ALIAS_NETPROTO(PF_SMC);
3646 MODULE_ALIAS_TCP_ULP("smc");
3647 /* 256 for IPPROTO_SMC and 1 for SOCK_STREAM */
3648 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 256, 1);
3649 #if IS_ENABLED(CONFIG_IPV6)
3650 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 256, 1);
3651 #endif /* CONFIG_IPV6 */
3652 MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);
3653