xref: /openbmc/linux/net/smc/af_smc.c (revision 52beb1fc)
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 
31 #include <net/sock.h>
32 #include <net/tcp.h>
33 #include <net/smc.h>
34 #include <asm/ioctls.h>
35 
36 #include <net/net_namespace.h>
37 #include <net/netns/generic.h>
38 #include "smc_netns.h"
39 
40 #include "smc.h"
41 #include "smc_clc.h"
42 #include "smc_llc.h"
43 #include "smc_cdc.h"
44 #include "smc_core.h"
45 #include "smc_ib.h"
46 #include "smc_ism.h"
47 #include "smc_pnet.h"
48 #include "smc_netlink.h"
49 #include "smc_tx.h"
50 #include "smc_rx.h"
51 #include "smc_close.h"
52 #include "smc_stats.h"
53 #include "smc_tracepoint.h"
54 
55 static DEFINE_MUTEX(smc_server_lgr_pending);	/* serialize link group
56 						 * creation on server
57 						 */
58 static DEFINE_MUTEX(smc_client_lgr_pending);	/* serialize link group
59 						 * creation on client
60 						 */
61 
62 struct workqueue_struct	*smc_hs_wq;	/* wq for handshake work */
63 struct workqueue_struct	*smc_close_wq;	/* wq for close work */
64 
65 static void smc_tcp_listen_work(struct work_struct *);
66 static void smc_connect_work(struct work_struct *);
67 
68 static void smc_set_keepalive(struct sock *sk, int val)
69 {
70 	struct smc_sock *smc = smc_sk(sk);
71 
72 	smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
73 }
74 
75 static struct smc_hashinfo smc_v4_hashinfo = {
76 	.lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
77 };
78 
79 static struct smc_hashinfo smc_v6_hashinfo = {
80 	.lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
81 };
82 
83 int smc_hash_sk(struct sock *sk)
84 {
85 	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
86 	struct hlist_head *head;
87 
88 	head = &h->ht;
89 
90 	write_lock_bh(&h->lock);
91 	sk_add_node(sk, head);
92 	write_unlock_bh(&h->lock);
93 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
94 
95 	return 0;
96 }
97 EXPORT_SYMBOL_GPL(smc_hash_sk);
98 
99 void smc_unhash_sk(struct sock *sk)
100 {
101 	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
102 
103 	write_lock_bh(&h->lock);
104 	if (sk_del_node_init(sk))
105 		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
106 	write_unlock_bh(&h->lock);
107 }
108 EXPORT_SYMBOL_GPL(smc_unhash_sk);
109 
110 struct proto smc_proto = {
111 	.name		= "SMC",
112 	.owner		= THIS_MODULE,
113 	.keepalive	= smc_set_keepalive,
114 	.hash		= smc_hash_sk,
115 	.unhash		= smc_unhash_sk,
116 	.obj_size	= sizeof(struct smc_sock),
117 	.h.smc_hash	= &smc_v4_hashinfo,
118 	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
119 };
120 EXPORT_SYMBOL_GPL(smc_proto);
121 
122 struct proto smc_proto6 = {
123 	.name		= "SMC6",
124 	.owner		= THIS_MODULE,
125 	.keepalive	= smc_set_keepalive,
126 	.hash		= smc_hash_sk,
127 	.unhash		= smc_unhash_sk,
128 	.obj_size	= sizeof(struct smc_sock),
129 	.h.smc_hash	= &smc_v6_hashinfo,
130 	.slab_flags	= SLAB_TYPESAFE_BY_RCU,
131 };
132 EXPORT_SYMBOL_GPL(smc_proto6);
133 
134 static void smc_restore_fallback_changes(struct smc_sock *smc)
135 {
136 	if (smc->clcsock->file) { /* non-accepted sockets have no file yet */
137 		smc->clcsock->file->private_data = smc->sk.sk_socket;
138 		smc->clcsock->file = NULL;
139 	}
140 }
141 
142 static int __smc_release(struct smc_sock *smc)
143 {
144 	struct sock *sk = &smc->sk;
145 	int rc = 0;
146 
147 	if (!smc->use_fallback) {
148 		rc = smc_close_active(smc);
149 		sock_set_flag(sk, SOCK_DEAD);
150 		sk->sk_shutdown |= SHUTDOWN_MASK;
151 	} else {
152 		if (sk->sk_state != SMC_CLOSED) {
153 			if (sk->sk_state != SMC_LISTEN &&
154 			    sk->sk_state != SMC_INIT)
155 				sock_put(sk); /* passive closing */
156 			if (sk->sk_state == SMC_LISTEN) {
157 				/* wake up clcsock accept */
158 				rc = kernel_sock_shutdown(smc->clcsock,
159 							  SHUT_RDWR);
160 			}
161 			sk->sk_state = SMC_CLOSED;
162 			sk->sk_state_change(sk);
163 		}
164 		smc_restore_fallback_changes(smc);
165 	}
166 
167 	sk->sk_prot->unhash(sk);
168 
169 	if (sk->sk_state == SMC_CLOSED) {
170 		if (smc->clcsock) {
171 			release_sock(sk);
172 			smc_clcsock_release(smc);
173 			lock_sock(sk);
174 		}
175 		if (!smc->use_fallback)
176 			smc_conn_free(&smc->conn);
177 	}
178 
179 	return rc;
180 }
181 
182 static int smc_release(struct socket *sock)
183 {
184 	struct sock *sk = sock->sk;
185 	struct smc_sock *smc;
186 	int rc = 0;
187 
188 	if (!sk)
189 		goto out;
190 
191 	sock_hold(sk); /* sock_put below */
192 	smc = smc_sk(sk);
193 
194 	/* cleanup for a dangling non-blocking connect */
195 	if (smc->connect_nonblock && sk->sk_state == SMC_INIT)
196 		tcp_abort(smc->clcsock->sk, ECONNABORTED);
197 
198 	if (cancel_work_sync(&smc->connect_work))
199 		sock_put(&smc->sk); /* sock_hold in smc_connect for passive closing */
200 
201 	if (sk->sk_state == SMC_LISTEN)
202 		/* smc_close_non_accepted() is called and acquires
203 		 * sock lock for child sockets again
204 		 */
205 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
206 	else
207 		lock_sock(sk);
208 
209 	rc = __smc_release(smc);
210 
211 	/* detach socket */
212 	sock_orphan(sk);
213 	sock->sk = NULL;
214 	release_sock(sk);
215 
216 	sock_put(sk); /* sock_hold above */
217 	sock_put(sk); /* final sock_put */
218 out:
219 	return rc;
220 }
221 
222 static void smc_destruct(struct sock *sk)
223 {
224 	if (sk->sk_state != SMC_CLOSED)
225 		return;
226 	if (!sock_flag(sk, SOCK_DEAD))
227 		return;
228 
229 	sk_refcnt_debug_dec(sk);
230 }
231 
232 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
233 				   int protocol)
234 {
235 	struct smc_sock *smc;
236 	struct proto *prot;
237 	struct sock *sk;
238 
239 	prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
240 	sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
241 	if (!sk)
242 		return NULL;
243 
244 	sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
245 	sk->sk_state = SMC_INIT;
246 	sk->sk_destruct = smc_destruct;
247 	sk->sk_protocol = protocol;
248 	smc = smc_sk(sk);
249 	INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
250 	INIT_WORK(&smc->connect_work, smc_connect_work);
251 	INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
252 	INIT_LIST_HEAD(&smc->accept_q);
253 	spin_lock_init(&smc->accept_q_lock);
254 	spin_lock_init(&smc->conn.send_lock);
255 	sk->sk_prot->hash(sk);
256 	sk_refcnt_debug_inc(sk);
257 	mutex_init(&smc->clcsock_release_lock);
258 
259 	return sk;
260 }
261 
262 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
263 		    int addr_len)
264 {
265 	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
266 	struct sock *sk = sock->sk;
267 	struct smc_sock *smc;
268 	int rc;
269 
270 	smc = smc_sk(sk);
271 
272 	/* replicate tests from inet_bind(), to be safe wrt. future changes */
273 	rc = -EINVAL;
274 	if (addr_len < sizeof(struct sockaddr_in))
275 		goto out;
276 
277 	rc = -EAFNOSUPPORT;
278 	if (addr->sin_family != AF_INET &&
279 	    addr->sin_family != AF_INET6 &&
280 	    addr->sin_family != AF_UNSPEC)
281 		goto out;
282 	/* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
283 	if (addr->sin_family == AF_UNSPEC &&
284 	    addr->sin_addr.s_addr != htonl(INADDR_ANY))
285 		goto out;
286 
287 	lock_sock(sk);
288 
289 	/* Check if socket is already active */
290 	rc = -EINVAL;
291 	if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
292 		goto out_rel;
293 
294 	smc->clcsock->sk->sk_reuse = sk->sk_reuse;
295 	rc = kernel_bind(smc->clcsock, uaddr, addr_len);
296 
297 out_rel:
298 	release_sock(sk);
299 out:
300 	return rc;
301 }
302 
303 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
304 				   unsigned long mask)
305 {
306 	/* options we don't get control via setsockopt for */
307 	nsk->sk_type = osk->sk_type;
308 	nsk->sk_sndbuf = osk->sk_sndbuf;
309 	nsk->sk_rcvbuf = osk->sk_rcvbuf;
310 	nsk->sk_sndtimeo = osk->sk_sndtimeo;
311 	nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
312 	nsk->sk_mark = osk->sk_mark;
313 	nsk->sk_priority = osk->sk_priority;
314 	nsk->sk_rcvlowat = osk->sk_rcvlowat;
315 	nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
316 	nsk->sk_err = osk->sk_err;
317 
318 	nsk->sk_flags &= ~mask;
319 	nsk->sk_flags |= osk->sk_flags & mask;
320 }
321 
322 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
323 			     (1UL << SOCK_KEEPOPEN) | \
324 			     (1UL << SOCK_LINGER) | \
325 			     (1UL << SOCK_BROADCAST) | \
326 			     (1UL << SOCK_TIMESTAMP) | \
327 			     (1UL << SOCK_DBG) | \
328 			     (1UL << SOCK_RCVTSTAMP) | \
329 			     (1UL << SOCK_RCVTSTAMPNS) | \
330 			     (1UL << SOCK_LOCALROUTE) | \
331 			     (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
332 			     (1UL << SOCK_RXQ_OVFL) | \
333 			     (1UL << SOCK_WIFI_STATUS) | \
334 			     (1UL << SOCK_NOFCS) | \
335 			     (1UL << SOCK_FILTER_LOCKED) | \
336 			     (1UL << SOCK_TSTAMP_NEW))
337 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
338  * clc socket (since smc is not called for these options from net/core)
339  */
340 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
341 {
342 	smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
343 }
344 
345 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
346 			     (1UL << SOCK_KEEPOPEN) | \
347 			     (1UL << SOCK_LINGER) | \
348 			     (1UL << SOCK_DBG))
349 /* copy only settings and flags relevant for smc from clc to smc socket */
350 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
351 {
352 	smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
353 }
354 
355 /* register the new rmb on all links */
356 static int smcr_lgr_reg_rmbs(struct smc_link *link,
357 			     struct smc_buf_desc *rmb_desc)
358 {
359 	struct smc_link_group *lgr = link->lgr;
360 	int i, rc = 0;
361 
362 	rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
363 	if (rc)
364 		return rc;
365 	/* protect against parallel smc_llc_cli_rkey_exchange() and
366 	 * parallel smcr_link_reg_rmb()
367 	 */
368 	mutex_lock(&lgr->llc_conf_mutex);
369 	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
370 		if (!smc_link_active(&lgr->lnk[i]))
371 			continue;
372 		rc = smcr_link_reg_rmb(&lgr->lnk[i], rmb_desc);
373 		if (rc)
374 			goto out;
375 	}
376 
377 	/* exchange confirm_rkey msg with peer */
378 	rc = smc_llc_do_confirm_rkey(link, rmb_desc);
379 	if (rc) {
380 		rc = -EFAULT;
381 		goto out;
382 	}
383 	rmb_desc->is_conf_rkey = true;
384 out:
385 	mutex_unlock(&lgr->llc_conf_mutex);
386 	smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
387 	return rc;
388 }
389 
390 static int smcr_clnt_conf_first_link(struct smc_sock *smc)
391 {
392 	struct smc_link *link = smc->conn.lnk;
393 	struct smc_llc_qentry *qentry;
394 	int rc;
395 
396 	/* receive CONFIRM LINK request from server over RoCE fabric */
397 	qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
398 			      SMC_LLC_CONFIRM_LINK);
399 	if (!qentry) {
400 		struct smc_clc_msg_decline dclc;
401 
402 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
403 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
404 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
405 	}
406 	smc_llc_save_peer_uid(qentry);
407 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
408 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
409 	if (rc)
410 		return SMC_CLC_DECL_RMBE_EC;
411 
412 	rc = smc_ib_modify_qp_rts(link);
413 	if (rc)
414 		return SMC_CLC_DECL_ERR_RDYLNK;
415 
416 	smc_wr_remember_qp_attr(link);
417 
418 	if (smcr_link_reg_rmb(link, smc->conn.rmb_desc))
419 		return SMC_CLC_DECL_ERR_REGRMB;
420 
421 	/* confirm_rkey is implicit on 1st contact */
422 	smc->conn.rmb_desc->is_conf_rkey = true;
423 
424 	/* send CONFIRM LINK response over RoCE fabric */
425 	rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
426 	if (rc < 0)
427 		return SMC_CLC_DECL_TIMEOUT_CL;
428 
429 	smc_llc_link_active(link);
430 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
431 
432 	/* optional 2nd link, receive ADD LINK request from server */
433 	qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
434 			      SMC_LLC_ADD_LINK);
435 	if (!qentry) {
436 		struct smc_clc_msg_decline dclc;
437 
438 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
439 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
440 		if (rc == -EAGAIN)
441 			rc = 0; /* no DECLINE received, go with one link */
442 		return rc;
443 	}
444 	smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
445 	smc_llc_cli_add_link(link, qentry);
446 	return 0;
447 }
448 
449 static bool smc_isascii(char *hostname)
450 {
451 	int i;
452 
453 	for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
454 		if (!isascii(hostname[i]))
455 			return false;
456 	return true;
457 }
458 
459 static void smc_conn_save_peer_info_fce(struct smc_sock *smc,
460 					struct smc_clc_msg_accept_confirm *clc)
461 {
462 	struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
463 		(struct smc_clc_msg_accept_confirm_v2 *)clc;
464 	struct smc_clc_first_contact_ext *fce;
465 	int clc_v2_len;
466 
467 	if (clc->hdr.version == SMC_V1 ||
468 	    !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
469 		return;
470 
471 	if (smc->conn.lgr->is_smcd) {
472 		memcpy(smc->conn.lgr->negotiated_eid, clc_v2->d1.eid,
473 		       SMC_MAX_EID_LEN);
474 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
475 					 d1);
476 	} else {
477 		memcpy(smc->conn.lgr->negotiated_eid, clc_v2->r1.eid,
478 		       SMC_MAX_EID_LEN);
479 		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
480 					 r1);
481 	}
482 	fce = (struct smc_clc_first_contact_ext *)(((u8 *)clc_v2) + clc_v2_len);
483 	smc->conn.lgr->peer_os = fce->os_type;
484 	smc->conn.lgr->peer_smc_release = fce->release;
485 	if (smc_isascii(fce->hostname))
486 		memcpy(smc->conn.lgr->peer_hostname, fce->hostname,
487 		       SMC_MAX_HOSTNAME_LEN);
488 }
489 
490 static void smcr_conn_save_peer_info(struct smc_sock *smc,
491 				     struct smc_clc_msg_accept_confirm *clc)
492 {
493 	int bufsize = smc_uncompress_bufsize(clc->r0.rmbe_size);
494 
495 	smc->conn.peer_rmbe_idx = clc->r0.rmbe_idx;
496 	smc->conn.local_tx_ctrl.token = ntohl(clc->r0.rmbe_alert_token);
497 	smc->conn.peer_rmbe_size = bufsize;
498 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
499 	smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
500 }
501 
502 static void smcd_conn_save_peer_info(struct smc_sock *smc,
503 				     struct smc_clc_msg_accept_confirm *clc)
504 {
505 	int bufsize = smc_uncompress_bufsize(clc->d0.dmbe_size);
506 
507 	smc->conn.peer_rmbe_idx = clc->d0.dmbe_idx;
508 	smc->conn.peer_token = clc->d0.token;
509 	/* msg header takes up space in the buffer */
510 	smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
511 	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
512 	smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
513 }
514 
515 static void smc_conn_save_peer_info(struct smc_sock *smc,
516 				    struct smc_clc_msg_accept_confirm *clc)
517 {
518 	if (smc->conn.lgr->is_smcd)
519 		smcd_conn_save_peer_info(smc, clc);
520 	else
521 		smcr_conn_save_peer_info(smc, clc);
522 	smc_conn_save_peer_info_fce(smc, clc);
523 }
524 
525 static void smc_link_save_peer_info(struct smc_link *link,
526 				    struct smc_clc_msg_accept_confirm *clc,
527 				    struct smc_init_info *ini)
528 {
529 	link->peer_qpn = ntoh24(clc->r0.qpn);
530 	memcpy(link->peer_gid, ini->peer_gid, SMC_GID_SIZE);
531 	memcpy(link->peer_mac, ini->peer_mac, sizeof(link->peer_mac));
532 	link->peer_psn = ntoh24(clc->r0.psn);
533 	link->peer_mtu = clc->r0.qp_mtu;
534 }
535 
536 static void smc_stat_inc_fback_rsn_cnt(struct smc_sock *smc,
537 				       struct smc_stats_fback *fback_arr)
538 {
539 	int cnt;
540 
541 	for (cnt = 0; cnt < SMC_MAX_FBACK_RSN_CNT; cnt++) {
542 		if (fback_arr[cnt].fback_code == smc->fallback_rsn) {
543 			fback_arr[cnt].count++;
544 			break;
545 		}
546 		if (!fback_arr[cnt].fback_code) {
547 			fback_arr[cnt].fback_code = smc->fallback_rsn;
548 			fback_arr[cnt].count++;
549 			break;
550 		}
551 	}
552 }
553 
554 static void smc_stat_fallback(struct smc_sock *smc)
555 {
556 	struct net *net = sock_net(&smc->sk);
557 
558 	mutex_lock(&net->smc.mutex_fback_rsn);
559 	if (smc->listen_smc) {
560 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->srv);
561 		net->smc.fback_rsn->srv_fback_cnt++;
562 	} else {
563 		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->clnt);
564 		net->smc.fback_rsn->clnt_fback_cnt++;
565 	}
566 	mutex_unlock(&net->smc.mutex_fback_rsn);
567 }
568 
569 static void smc_switch_to_fallback(struct smc_sock *smc, int reason_code)
570 {
571 	wait_queue_head_t *smc_wait = sk_sleep(&smc->sk);
572 	wait_queue_head_t *clc_wait = sk_sleep(smc->clcsock->sk);
573 	unsigned long flags;
574 
575 	smc->use_fallback = true;
576 	smc->fallback_rsn = reason_code;
577 	smc_stat_fallback(smc);
578 	trace_smc_switch_to_fallback(smc, reason_code);
579 	if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
580 		smc->clcsock->file = smc->sk.sk_socket->file;
581 		smc->clcsock->file->private_data = smc->clcsock;
582 		smc->clcsock->wq.fasync_list =
583 			smc->sk.sk_socket->wq.fasync_list;
584 
585 		/* There may be some entries remaining in
586 		 * smc socket->wq, which should be removed
587 		 * to clcsocket->wq during the fallback.
588 		 */
589 		spin_lock_irqsave(&smc_wait->lock, flags);
590 		spin_lock_nested(&clc_wait->lock, SINGLE_DEPTH_NESTING);
591 		list_splice_init(&smc_wait->head, &clc_wait->head);
592 		spin_unlock(&clc_wait->lock);
593 		spin_unlock_irqrestore(&smc_wait->lock, flags);
594 	}
595 }
596 
597 /* fall back during connect */
598 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
599 {
600 	smc_switch_to_fallback(smc, reason_code);
601 	smc_copy_sock_settings_to_clc(smc);
602 	smc->connect_nonblock = 0;
603 	if (smc->sk.sk_state == SMC_INIT)
604 		smc->sk.sk_state = SMC_ACTIVE;
605 	return 0;
606 }
607 
608 /* decline and fall back during connect */
609 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
610 					u8 version)
611 {
612 	struct net *net = sock_net(&smc->sk);
613 	int rc;
614 
615 	if (reason_code < 0) { /* error, fallback is not possible */
616 		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
617 		if (smc->sk.sk_state == SMC_INIT)
618 			sock_put(&smc->sk); /* passive closing */
619 		return reason_code;
620 	}
621 	if (reason_code != SMC_CLC_DECL_PEERDECL) {
622 		rc = smc_clc_send_decline(smc, reason_code, version);
623 		if (rc < 0) {
624 			this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
625 			if (smc->sk.sk_state == SMC_INIT)
626 				sock_put(&smc->sk); /* passive closing */
627 			return rc;
628 		}
629 	}
630 	return smc_connect_fallback(smc, reason_code);
631 }
632 
633 static void smc_conn_abort(struct smc_sock *smc, int local_first)
634 {
635 	struct smc_connection *conn = &smc->conn;
636 	struct smc_link_group *lgr = conn->lgr;
637 	bool lgr_valid = false;
638 
639 	if (smc_conn_lgr_valid(conn))
640 		lgr_valid = true;
641 
642 	smc_conn_free(conn);
643 	if (local_first && lgr_valid)
644 		smc_lgr_cleanup_early(lgr);
645 }
646 
647 /* check if there is a rdma device available for this connection. */
648 /* called for connect and listen */
649 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
650 {
651 	/* PNET table look up: search active ib_device and port
652 	 * within same PNETID that also contains the ethernet device
653 	 * used for the internal TCP socket
654 	 */
655 	smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
656 	if (!ini->check_smcrv2 && !ini->ib_dev)
657 		return SMC_CLC_DECL_NOSMCRDEV;
658 	if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
659 		return SMC_CLC_DECL_NOSMCRDEV;
660 	return 0;
661 }
662 
663 /* check if there is an ISM device available for this connection. */
664 /* called for connect and listen */
665 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
666 {
667 	/* Find ISM device with same PNETID as connecting interface  */
668 	smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
669 	if (!ini->ism_dev[0])
670 		return SMC_CLC_DECL_NOSMCDDEV;
671 	else
672 		ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
673 	return 0;
674 }
675 
676 /* is chid unique for the ism devices that are already determined? */
677 static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
678 					   int cnt)
679 {
680 	int i = (!ini->ism_dev[0]) ? 1 : 0;
681 
682 	for (; i < cnt; i++)
683 		if (ini->ism_chid[i] == chid)
684 			return false;
685 	return true;
686 }
687 
688 /* determine possible V2 ISM devices (either without PNETID or with PNETID plus
689  * PNETID matching net_device)
690  */
691 static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
692 				       struct smc_init_info *ini)
693 {
694 	int rc = SMC_CLC_DECL_NOSMCDDEV;
695 	struct smcd_dev *smcd;
696 	int i = 1;
697 	u16 chid;
698 
699 	if (smcd_indicated(ini->smc_type_v1))
700 		rc = 0;		/* already initialized for V1 */
701 	mutex_lock(&smcd_dev_list.mutex);
702 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
703 		if (smcd->going_away || smcd == ini->ism_dev[0])
704 			continue;
705 		chid = smc_ism_get_chid(smcd);
706 		if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
707 			continue;
708 		if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
709 		    smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
710 			ini->ism_dev[i] = smcd;
711 			ini->ism_chid[i] = chid;
712 			ini->is_smcd = true;
713 			rc = 0;
714 			i++;
715 			if (i > SMC_MAX_ISM_DEVS)
716 				break;
717 		}
718 	}
719 	mutex_unlock(&smcd_dev_list.mutex);
720 	ini->ism_offered_cnt = i - 1;
721 	if (!ini->ism_dev[0] && !ini->ism_dev[1])
722 		ini->smcd_version = 0;
723 
724 	return rc;
725 }
726 
727 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
728 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
729 				      struct smc_init_info *ini)
730 {
731 	if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
732 		return SMC_CLC_DECL_ISMVLANERR;
733 	return 0;
734 }
735 
736 static int smc_find_proposal_devices(struct smc_sock *smc,
737 				     struct smc_init_info *ini)
738 {
739 	int rc = 0;
740 
741 	/* check if there is an ism device available */
742 	if (!(ini->smcd_version & SMC_V1) ||
743 	    smc_find_ism_device(smc, ini) ||
744 	    smc_connect_ism_vlan_setup(smc, ini))
745 		ini->smcd_version &= ~SMC_V1;
746 	/* else ISM V1 is supported for this connection */
747 
748 	/* check if there is an rdma device available */
749 	if (!(ini->smcr_version & SMC_V1) ||
750 	    smc_find_rdma_device(smc, ini))
751 		ini->smcr_version &= ~SMC_V1;
752 	/* else RDMA is supported for this connection */
753 
754 	ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
755 					      ini->smcr_version & SMC_V1);
756 
757 	/* check if there is an ism v2 device available */
758 	if (!(ini->smcd_version & SMC_V2) ||
759 	    !smc_ism_is_v2_capable() ||
760 	    smc_find_ism_v2_device_clnt(smc, ini))
761 		ini->smcd_version &= ~SMC_V2;
762 
763 	/* check if there is an rdma v2 device available */
764 	ini->check_smcrv2 = true;
765 	ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
766 	if (!(ini->smcr_version & SMC_V2) ||
767 	    smc->clcsock->sk->sk_family != AF_INET ||
768 	    !smc_clc_ueid_count() ||
769 	    smc_find_rdma_device(smc, ini))
770 		ini->smcr_version &= ~SMC_V2;
771 	ini->check_smcrv2 = false;
772 
773 	ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
774 					      ini->smcr_version & SMC_V2);
775 
776 	/* if neither ISM nor RDMA are supported, fallback */
777 	if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
778 		rc = SMC_CLC_DECL_NOSMCDEV;
779 
780 	return rc;
781 }
782 
783 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
784  * used, the VLAN ID will be registered again during the connection setup.
785  */
786 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
787 					struct smc_init_info *ini)
788 {
789 	if (!smcd_indicated(ini->smc_type_v1))
790 		return 0;
791 	if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
792 		return SMC_CLC_DECL_CNFERR;
793 	return 0;
794 }
795 
796 #define SMC_CLC_MAX_ACCEPT_LEN \
797 	(sizeof(struct smc_clc_msg_accept_confirm_v2) + \
798 	 sizeof(struct smc_clc_first_contact_ext) + \
799 	 sizeof(struct smc_clc_msg_trail))
800 
801 /* CLC handshake during connect */
802 static int smc_connect_clc(struct smc_sock *smc,
803 			   struct smc_clc_msg_accept_confirm_v2 *aclc2,
804 			   struct smc_init_info *ini)
805 {
806 	int rc = 0;
807 
808 	/* do inband token exchange */
809 	rc = smc_clc_send_proposal(smc, ini);
810 	if (rc)
811 		return rc;
812 	/* receive SMC Accept CLC message */
813 	return smc_clc_wait_msg(smc, aclc2, SMC_CLC_MAX_ACCEPT_LEN,
814 				SMC_CLC_ACCEPT, CLC_WAIT_TIME);
815 }
816 
817 void smc_fill_gid_list(struct smc_link_group *lgr,
818 		       struct smc_gidlist *gidlist,
819 		       struct smc_ib_device *known_dev, u8 *known_gid)
820 {
821 	struct smc_init_info *alt_ini = NULL;
822 
823 	memset(gidlist, 0, sizeof(*gidlist));
824 	memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
825 
826 	alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
827 	if (!alt_ini)
828 		goto out;
829 
830 	alt_ini->vlan_id = lgr->vlan_id;
831 	alt_ini->check_smcrv2 = true;
832 	alt_ini->smcrv2.saddr = lgr->saddr;
833 	smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
834 
835 	if (!alt_ini->smcrv2.ib_dev_v2)
836 		goto out;
837 
838 	memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
839 	       SMC_GID_SIZE);
840 
841 out:
842 	kfree(alt_ini);
843 }
844 
845 static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
846 				       struct smc_clc_msg_accept_confirm *aclc,
847 				       struct smc_init_info *ini)
848 {
849 	struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
850 		(struct smc_clc_msg_accept_confirm_v2 *)aclc;
851 	struct smc_clc_first_contact_ext *fce =
852 		(struct smc_clc_first_contact_ext *)
853 			(((u8 *)clc_v2) + sizeof(*clc_v2));
854 
855 	if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
856 		return 0;
857 
858 	if (fce->v2_direct) {
859 		memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
860 		ini->smcrv2.uses_gateway = false;
861 	} else {
862 		if (smc_ib_find_route(smc->clcsock->sk->sk_rcv_saddr,
863 				      smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
864 				      ini->smcrv2.nexthop_mac,
865 				      &ini->smcrv2.uses_gateway))
866 			return SMC_CLC_DECL_NOROUTE;
867 		if (!ini->smcrv2.uses_gateway) {
868 			/* mismatch: peer claims indirect, but its direct */
869 			return SMC_CLC_DECL_NOINDIRECT;
870 		}
871 	}
872 	return 0;
873 }
874 
875 /* setup for RDMA connection of client */
876 static int smc_connect_rdma(struct smc_sock *smc,
877 			    struct smc_clc_msg_accept_confirm *aclc,
878 			    struct smc_init_info *ini)
879 {
880 	int i, reason_code = 0;
881 	struct smc_link *link;
882 	u8 *eid = NULL;
883 
884 	ini->is_smcd = false;
885 	ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
886 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
887 	memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
888 	memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
889 	memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
890 
891 	reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
892 	if (reason_code)
893 		return reason_code;
894 
895 	mutex_lock(&smc_client_lgr_pending);
896 	reason_code = smc_conn_create(smc, ini);
897 	if (reason_code) {
898 		mutex_unlock(&smc_client_lgr_pending);
899 		return reason_code;
900 	}
901 
902 	smc_conn_save_peer_info(smc, aclc);
903 
904 	if (ini->first_contact_local) {
905 		link = smc->conn.lnk;
906 	} else {
907 		/* set link that was assigned by server */
908 		link = NULL;
909 		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
910 			struct smc_link *l = &smc->conn.lgr->lnk[i];
911 
912 			if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
913 			    !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
914 				    SMC_GID_SIZE) &&
915 			    (aclc->hdr.version > SMC_V1 ||
916 			     !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
917 				     sizeof(l->peer_mac)))) {
918 				link = l;
919 				break;
920 			}
921 		}
922 		if (!link) {
923 			reason_code = SMC_CLC_DECL_NOSRVLINK;
924 			goto connect_abort;
925 		}
926 		smc_switch_link_and_count(&smc->conn, link);
927 	}
928 
929 	/* create send buffer and rmb */
930 	if (smc_buf_create(smc, false)) {
931 		reason_code = SMC_CLC_DECL_MEM;
932 		goto connect_abort;
933 	}
934 
935 	if (ini->first_contact_local)
936 		smc_link_save_peer_info(link, aclc, ini);
937 
938 	if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
939 		reason_code = SMC_CLC_DECL_ERR_RTOK;
940 		goto connect_abort;
941 	}
942 
943 	smc_close_init(smc);
944 	smc_rx_init(smc);
945 
946 	if (ini->first_contact_local) {
947 		if (smc_ib_ready_link(link)) {
948 			reason_code = SMC_CLC_DECL_ERR_RDYLNK;
949 			goto connect_abort;
950 		}
951 	} else {
952 		if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
953 			reason_code = SMC_CLC_DECL_ERR_REGRMB;
954 			goto connect_abort;
955 		}
956 	}
957 	smc_rmb_sync_sg_for_device(&smc->conn);
958 
959 	if (aclc->hdr.version > SMC_V1) {
960 		struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
961 			(struct smc_clc_msg_accept_confirm_v2 *)aclc;
962 
963 		eid = clc_v2->r1.eid;
964 		if (ini->first_contact_local)
965 			smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
966 					  link->smcibdev, link->gid);
967 	}
968 
969 	reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
970 					   aclc->hdr.version, eid, ini);
971 	if (reason_code)
972 		goto connect_abort;
973 
974 	smc_tx_init(smc);
975 
976 	if (ini->first_contact_local) {
977 		/* QP confirmation over RoCE fabric */
978 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
979 		reason_code = smcr_clnt_conf_first_link(smc);
980 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
981 		if (reason_code)
982 			goto connect_abort;
983 	}
984 	mutex_unlock(&smc_client_lgr_pending);
985 
986 	smc_copy_sock_settings_to_clc(smc);
987 	smc->connect_nonblock = 0;
988 	if (smc->sk.sk_state == SMC_INIT)
989 		smc->sk.sk_state = SMC_ACTIVE;
990 
991 	return 0;
992 connect_abort:
993 	smc_conn_abort(smc, ini->first_contact_local);
994 	mutex_unlock(&smc_client_lgr_pending);
995 	smc->connect_nonblock = 0;
996 
997 	return reason_code;
998 }
999 
1000 /* The server has chosen one of the proposed ISM devices for the communication.
1001  * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1002  */
1003 static int
1004 smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm_v2 *aclc,
1005 			       struct smc_init_info *ini)
1006 {
1007 	int i;
1008 
1009 	for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1010 		if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1011 			ini->ism_selected = i;
1012 			return 0;
1013 		}
1014 	}
1015 
1016 	return -EPROTO;
1017 }
1018 
1019 /* setup for ISM connection of client */
1020 static int smc_connect_ism(struct smc_sock *smc,
1021 			   struct smc_clc_msg_accept_confirm *aclc,
1022 			   struct smc_init_info *ini)
1023 {
1024 	u8 *eid = NULL;
1025 	int rc = 0;
1026 
1027 	ini->is_smcd = true;
1028 	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1029 
1030 	if (aclc->hdr.version == SMC_V2) {
1031 		struct smc_clc_msg_accept_confirm_v2 *aclc_v2 =
1032 			(struct smc_clc_msg_accept_confirm_v2 *)aclc;
1033 
1034 		rc = smc_v2_determine_accepted_chid(aclc_v2, ini);
1035 		if (rc)
1036 			return rc;
1037 	}
1038 	ini->ism_peer_gid[ini->ism_selected] = aclc->d0.gid;
1039 
1040 	/* there is only one lgr role for SMC-D; use server lock */
1041 	mutex_lock(&smc_server_lgr_pending);
1042 	rc = smc_conn_create(smc, ini);
1043 	if (rc) {
1044 		mutex_unlock(&smc_server_lgr_pending);
1045 		return rc;
1046 	}
1047 
1048 	/* Create send and receive buffers */
1049 	rc = smc_buf_create(smc, true);
1050 	if (rc) {
1051 		rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1052 		goto connect_abort;
1053 	}
1054 
1055 	smc_conn_save_peer_info(smc, aclc);
1056 	smc_close_init(smc);
1057 	smc_rx_init(smc);
1058 	smc_tx_init(smc);
1059 
1060 	if (aclc->hdr.version > SMC_V1) {
1061 		struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1062 			(struct smc_clc_msg_accept_confirm_v2 *)aclc;
1063 
1064 		eid = clc_v2->d1.eid;
1065 	}
1066 
1067 	rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1068 				  aclc->hdr.version, eid, NULL);
1069 	if (rc)
1070 		goto connect_abort;
1071 	mutex_unlock(&smc_server_lgr_pending);
1072 
1073 	smc_copy_sock_settings_to_clc(smc);
1074 	smc->connect_nonblock = 0;
1075 	if (smc->sk.sk_state == SMC_INIT)
1076 		smc->sk.sk_state = SMC_ACTIVE;
1077 
1078 	return 0;
1079 connect_abort:
1080 	smc_conn_abort(smc, ini->first_contact_local);
1081 	mutex_unlock(&smc_server_lgr_pending);
1082 	smc->connect_nonblock = 0;
1083 
1084 	return rc;
1085 }
1086 
1087 /* check if received accept type and version matches a proposed one */
1088 static int smc_connect_check_aclc(struct smc_init_info *ini,
1089 				  struct smc_clc_msg_accept_confirm *aclc)
1090 {
1091 	if (aclc->hdr.typev1 != SMC_TYPE_R &&
1092 	    aclc->hdr.typev1 != SMC_TYPE_D)
1093 		return SMC_CLC_DECL_MODEUNSUPP;
1094 
1095 	if (aclc->hdr.version >= SMC_V2) {
1096 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1097 		     !smcr_indicated(ini->smc_type_v2)) ||
1098 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1099 		     !smcd_indicated(ini->smc_type_v2)))
1100 			return SMC_CLC_DECL_MODEUNSUPP;
1101 	} else {
1102 		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1103 		     !smcr_indicated(ini->smc_type_v1)) ||
1104 		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1105 		     !smcd_indicated(ini->smc_type_v1)))
1106 			return SMC_CLC_DECL_MODEUNSUPP;
1107 	}
1108 
1109 	return 0;
1110 }
1111 
1112 /* perform steps before actually connecting */
1113 static int __smc_connect(struct smc_sock *smc)
1114 {
1115 	u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1116 	struct smc_clc_msg_accept_confirm_v2 *aclc2;
1117 	struct smc_clc_msg_accept_confirm *aclc;
1118 	struct smc_init_info *ini = NULL;
1119 	u8 *buf = NULL;
1120 	int rc = 0;
1121 
1122 	if (smc->use_fallback)
1123 		return smc_connect_fallback(smc, smc->fallback_rsn);
1124 
1125 	/* if peer has not signalled SMC-capability, fall back */
1126 	if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1127 		return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1128 
1129 	/* IPSec connections opt out of SMC optimizations */
1130 	if (using_ipsec(smc))
1131 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1132 						    version);
1133 
1134 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1135 	if (!ini)
1136 		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1137 						    version);
1138 
1139 	ini->smcd_version = SMC_V1 | SMC_V2;
1140 	ini->smcr_version = SMC_V1 | SMC_V2;
1141 	ini->smc_type_v1 = SMC_TYPE_B;
1142 	ini->smc_type_v2 = SMC_TYPE_B;
1143 
1144 	/* get vlan id from IP device */
1145 	if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1146 		ini->smcd_version &= ~SMC_V1;
1147 		ini->smcr_version = 0;
1148 		ini->smc_type_v1 = SMC_TYPE_N;
1149 		if (!ini->smcd_version) {
1150 			rc = SMC_CLC_DECL_GETVLANERR;
1151 			goto fallback;
1152 		}
1153 	}
1154 
1155 	rc = smc_find_proposal_devices(smc, ini);
1156 	if (rc)
1157 		goto fallback;
1158 
1159 	buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1160 	if (!buf) {
1161 		rc = SMC_CLC_DECL_MEM;
1162 		goto fallback;
1163 	}
1164 	aclc2 = (struct smc_clc_msg_accept_confirm_v2 *)buf;
1165 	aclc = (struct smc_clc_msg_accept_confirm *)aclc2;
1166 
1167 	/* perform CLC handshake */
1168 	rc = smc_connect_clc(smc, aclc2, ini);
1169 	if (rc)
1170 		goto vlan_cleanup;
1171 
1172 	/* check if smc modes and versions of CLC proposal and accept match */
1173 	rc = smc_connect_check_aclc(ini, aclc);
1174 	version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1175 	if (rc)
1176 		goto vlan_cleanup;
1177 
1178 	/* depending on previous steps, connect using rdma or ism */
1179 	if (aclc->hdr.typev1 == SMC_TYPE_R) {
1180 		ini->smcr_version = version;
1181 		rc = smc_connect_rdma(smc, aclc, ini);
1182 	} else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1183 		ini->smcd_version = version;
1184 		rc = smc_connect_ism(smc, aclc, ini);
1185 	}
1186 	if (rc)
1187 		goto vlan_cleanup;
1188 
1189 	SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1190 	smc_connect_ism_vlan_cleanup(smc, ini);
1191 	kfree(buf);
1192 	kfree(ini);
1193 	return 0;
1194 
1195 vlan_cleanup:
1196 	smc_connect_ism_vlan_cleanup(smc, ini);
1197 	kfree(buf);
1198 fallback:
1199 	kfree(ini);
1200 	return smc_connect_decline_fallback(smc, rc, version);
1201 }
1202 
1203 static void smc_connect_work(struct work_struct *work)
1204 {
1205 	struct smc_sock *smc = container_of(work, struct smc_sock,
1206 					    connect_work);
1207 	long timeo = smc->sk.sk_sndtimeo;
1208 	int rc = 0;
1209 
1210 	if (!timeo)
1211 		timeo = MAX_SCHEDULE_TIMEOUT;
1212 	lock_sock(smc->clcsock->sk);
1213 	if (smc->clcsock->sk->sk_err) {
1214 		smc->sk.sk_err = smc->clcsock->sk->sk_err;
1215 	} else if ((1 << smc->clcsock->sk->sk_state) &
1216 					(TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1217 		rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1218 		if ((rc == -EPIPE) &&
1219 		    ((1 << smc->clcsock->sk->sk_state) &
1220 					(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1221 			rc = 0;
1222 	}
1223 	release_sock(smc->clcsock->sk);
1224 	lock_sock(&smc->sk);
1225 	if (rc != 0 || smc->sk.sk_err) {
1226 		smc->sk.sk_state = SMC_CLOSED;
1227 		if (rc == -EPIPE || rc == -EAGAIN)
1228 			smc->sk.sk_err = EPIPE;
1229 		else if (signal_pending(current))
1230 			smc->sk.sk_err = -sock_intr_errno(timeo);
1231 		sock_put(&smc->sk); /* passive closing */
1232 		goto out;
1233 	}
1234 
1235 	rc = __smc_connect(smc);
1236 	if (rc < 0)
1237 		smc->sk.sk_err = -rc;
1238 
1239 out:
1240 	if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1241 		if (smc->sk.sk_err) {
1242 			smc->sk.sk_state_change(&smc->sk);
1243 		} else { /* allow polling before and after fallback decision */
1244 			smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1245 			smc->sk.sk_write_space(&smc->sk);
1246 		}
1247 	}
1248 	release_sock(&smc->sk);
1249 }
1250 
1251 static int smc_connect(struct socket *sock, struct sockaddr *addr,
1252 		       int alen, int flags)
1253 {
1254 	struct sock *sk = sock->sk;
1255 	struct smc_sock *smc;
1256 	int rc = -EINVAL;
1257 
1258 	smc = smc_sk(sk);
1259 
1260 	/* separate smc parameter checking to be safe */
1261 	if (alen < sizeof(addr->sa_family))
1262 		goto out_err;
1263 	if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1264 		goto out_err;
1265 
1266 	lock_sock(sk);
1267 	switch (sk->sk_state) {
1268 	default:
1269 		goto out;
1270 	case SMC_ACTIVE:
1271 		rc = -EISCONN;
1272 		goto out;
1273 	case SMC_INIT:
1274 		break;
1275 	}
1276 
1277 	smc_copy_sock_settings_to_clc(smc);
1278 	tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1279 	if (smc->connect_nonblock) {
1280 		rc = -EALREADY;
1281 		goto out;
1282 	}
1283 	rc = kernel_connect(smc->clcsock, addr, alen, flags);
1284 	if (rc && rc != -EINPROGRESS)
1285 		goto out;
1286 
1287 	sock_hold(&smc->sk); /* sock put in passive closing */
1288 	if (smc->use_fallback)
1289 		goto out;
1290 	if (flags & O_NONBLOCK) {
1291 		if (queue_work(smc_hs_wq, &smc->connect_work))
1292 			smc->connect_nonblock = 1;
1293 		rc = -EINPROGRESS;
1294 	} else {
1295 		rc = __smc_connect(smc);
1296 		if (rc < 0)
1297 			goto out;
1298 		else
1299 			rc = 0; /* success cases including fallback */
1300 	}
1301 
1302 out:
1303 	release_sock(sk);
1304 out_err:
1305 	return rc;
1306 }
1307 
1308 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1309 {
1310 	struct socket *new_clcsock = NULL;
1311 	struct sock *lsk = &lsmc->sk;
1312 	struct sock *new_sk;
1313 	int rc = -EINVAL;
1314 
1315 	release_sock(lsk);
1316 	new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1317 	if (!new_sk) {
1318 		rc = -ENOMEM;
1319 		lsk->sk_err = ENOMEM;
1320 		*new_smc = NULL;
1321 		lock_sock(lsk);
1322 		goto out;
1323 	}
1324 	*new_smc = smc_sk(new_sk);
1325 
1326 	mutex_lock(&lsmc->clcsock_release_lock);
1327 	if (lsmc->clcsock)
1328 		rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1329 	mutex_unlock(&lsmc->clcsock_release_lock);
1330 	lock_sock(lsk);
1331 	if  (rc < 0 && rc != -EAGAIN)
1332 		lsk->sk_err = -rc;
1333 	if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1334 		new_sk->sk_prot->unhash(new_sk);
1335 		if (new_clcsock)
1336 			sock_release(new_clcsock);
1337 		new_sk->sk_state = SMC_CLOSED;
1338 		sock_set_flag(new_sk, SOCK_DEAD);
1339 		sock_put(new_sk); /* final */
1340 		*new_smc = NULL;
1341 		goto out;
1342 	}
1343 
1344 	/* new clcsock has inherited the smc listen-specific sk_data_ready
1345 	 * function; switch it back to the original sk_data_ready function
1346 	 */
1347 	new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1348 	(*new_smc)->clcsock = new_clcsock;
1349 out:
1350 	return rc;
1351 }
1352 
1353 /* add a just created sock to the accept queue of the listen sock as
1354  * candidate for a following socket accept call from user space
1355  */
1356 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1357 {
1358 	struct smc_sock *par = smc_sk(parent);
1359 
1360 	sock_hold(sk); /* sock_put in smc_accept_unlink () */
1361 	spin_lock(&par->accept_q_lock);
1362 	list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1363 	spin_unlock(&par->accept_q_lock);
1364 	sk_acceptq_added(parent);
1365 }
1366 
1367 /* remove a socket from the accept queue of its parental listening socket */
1368 static void smc_accept_unlink(struct sock *sk)
1369 {
1370 	struct smc_sock *par = smc_sk(sk)->listen_smc;
1371 
1372 	spin_lock(&par->accept_q_lock);
1373 	list_del_init(&smc_sk(sk)->accept_q);
1374 	spin_unlock(&par->accept_q_lock);
1375 	sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1376 	sock_put(sk); /* sock_hold in smc_accept_enqueue */
1377 }
1378 
1379 /* remove a sock from the accept queue to bind it to a new socket created
1380  * for a socket accept call from user space
1381  */
1382 struct sock *smc_accept_dequeue(struct sock *parent,
1383 				struct socket *new_sock)
1384 {
1385 	struct smc_sock *isk, *n;
1386 	struct sock *new_sk;
1387 
1388 	list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1389 		new_sk = (struct sock *)isk;
1390 
1391 		smc_accept_unlink(new_sk);
1392 		if (new_sk->sk_state == SMC_CLOSED) {
1393 			new_sk->sk_prot->unhash(new_sk);
1394 			if (isk->clcsock) {
1395 				sock_release(isk->clcsock);
1396 				isk->clcsock = NULL;
1397 			}
1398 			sock_put(new_sk); /* final */
1399 			continue;
1400 		}
1401 		if (new_sock) {
1402 			sock_graft(new_sk, new_sock);
1403 			if (isk->use_fallback) {
1404 				smc_sk(new_sk)->clcsock->file = new_sock->file;
1405 				isk->clcsock->file->private_data = isk->clcsock;
1406 			}
1407 		}
1408 		return new_sk;
1409 	}
1410 	return NULL;
1411 }
1412 
1413 /* clean up for a created but never accepted sock */
1414 void smc_close_non_accepted(struct sock *sk)
1415 {
1416 	struct smc_sock *smc = smc_sk(sk);
1417 
1418 	sock_hold(sk); /* sock_put below */
1419 	lock_sock(sk);
1420 	if (!sk->sk_lingertime)
1421 		/* wait for peer closing */
1422 		sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
1423 	__smc_release(smc);
1424 	release_sock(sk);
1425 	sock_put(sk); /* sock_hold above */
1426 	sock_put(sk); /* final sock_put */
1427 }
1428 
1429 static int smcr_serv_conf_first_link(struct smc_sock *smc)
1430 {
1431 	struct smc_link *link = smc->conn.lnk;
1432 	struct smc_llc_qentry *qentry;
1433 	int rc;
1434 
1435 	if (smcr_link_reg_rmb(link, smc->conn.rmb_desc))
1436 		return SMC_CLC_DECL_ERR_REGRMB;
1437 
1438 	/* send CONFIRM LINK request to client over the RoCE fabric */
1439 	rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1440 	if (rc < 0)
1441 		return SMC_CLC_DECL_TIMEOUT_CL;
1442 
1443 	/* receive CONFIRM LINK response from client over the RoCE fabric */
1444 	qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1445 			      SMC_LLC_CONFIRM_LINK);
1446 	if (!qentry) {
1447 		struct smc_clc_msg_decline dclc;
1448 
1449 		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1450 				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1451 		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1452 	}
1453 	smc_llc_save_peer_uid(qentry);
1454 	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1455 	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1456 	if (rc)
1457 		return SMC_CLC_DECL_RMBE_EC;
1458 
1459 	/* confirm_rkey is implicit on 1st contact */
1460 	smc->conn.rmb_desc->is_conf_rkey = true;
1461 
1462 	smc_llc_link_active(link);
1463 	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1464 
1465 	/* initial contact - try to establish second link */
1466 	smc_llc_srv_add_link(link, NULL);
1467 	return 0;
1468 }
1469 
1470 /* listen worker: finish */
1471 static void smc_listen_out(struct smc_sock *new_smc)
1472 {
1473 	struct smc_sock *lsmc = new_smc->listen_smc;
1474 	struct sock *newsmcsk = &new_smc->sk;
1475 
1476 	if (lsmc->sk.sk_state == SMC_LISTEN) {
1477 		lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1478 		smc_accept_enqueue(&lsmc->sk, newsmcsk);
1479 		release_sock(&lsmc->sk);
1480 	} else { /* no longer listening */
1481 		smc_close_non_accepted(newsmcsk);
1482 	}
1483 
1484 	/* Wake up accept */
1485 	lsmc->sk.sk_data_ready(&lsmc->sk);
1486 	sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1487 }
1488 
1489 /* listen worker: finish in state connected */
1490 static void smc_listen_out_connected(struct smc_sock *new_smc)
1491 {
1492 	struct sock *newsmcsk = &new_smc->sk;
1493 
1494 	sk_refcnt_debug_inc(newsmcsk);
1495 	if (newsmcsk->sk_state == SMC_INIT)
1496 		newsmcsk->sk_state = SMC_ACTIVE;
1497 
1498 	smc_listen_out(new_smc);
1499 }
1500 
1501 /* listen worker: finish in error state */
1502 static void smc_listen_out_err(struct smc_sock *new_smc)
1503 {
1504 	struct sock *newsmcsk = &new_smc->sk;
1505 	struct net *net = sock_net(newsmcsk);
1506 
1507 	this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1508 	if (newsmcsk->sk_state == SMC_INIT)
1509 		sock_put(&new_smc->sk); /* passive closing */
1510 	newsmcsk->sk_state = SMC_CLOSED;
1511 
1512 	smc_listen_out(new_smc);
1513 }
1514 
1515 /* listen worker: decline and fall back if possible */
1516 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1517 			       int local_first, u8 version)
1518 {
1519 	/* RDMA setup failed, switch back to TCP */
1520 	smc_conn_abort(new_smc, local_first);
1521 	if (reason_code < 0) { /* error, no fallback possible */
1522 		smc_listen_out_err(new_smc);
1523 		return;
1524 	}
1525 	smc_switch_to_fallback(new_smc, reason_code);
1526 	if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1527 		if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1528 			smc_listen_out_err(new_smc);
1529 			return;
1530 		}
1531 	}
1532 	smc_listen_out_connected(new_smc);
1533 }
1534 
1535 /* listen worker: version checking */
1536 static int smc_listen_v2_check(struct smc_sock *new_smc,
1537 			       struct smc_clc_msg_proposal *pclc,
1538 			       struct smc_init_info *ini)
1539 {
1540 	struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1541 	struct smc_clc_v2_extension *pclc_v2_ext;
1542 	int rc = SMC_CLC_DECL_PEERNOSMC;
1543 
1544 	ini->smc_type_v1 = pclc->hdr.typev1;
1545 	ini->smc_type_v2 = pclc->hdr.typev2;
1546 	ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1547 	ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1548 	if (pclc->hdr.version > SMC_V1) {
1549 		if (smcd_indicated(ini->smc_type_v2))
1550 			ini->smcd_version |= SMC_V2;
1551 		if (smcr_indicated(ini->smc_type_v2))
1552 			ini->smcr_version |= SMC_V2;
1553 	}
1554 	if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1555 		rc = SMC_CLC_DECL_PEERNOSMC;
1556 		goto out;
1557 	}
1558 	pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1559 	if (!pclc_v2_ext) {
1560 		ini->smcd_version &= ~SMC_V2;
1561 		ini->smcr_version &= ~SMC_V2;
1562 		rc = SMC_CLC_DECL_NOV2EXT;
1563 		goto out;
1564 	}
1565 	pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
1566 	if (ini->smcd_version & SMC_V2) {
1567 		if (!smc_ism_is_v2_capable()) {
1568 			ini->smcd_version &= ~SMC_V2;
1569 			rc = SMC_CLC_DECL_NOISM2SUPP;
1570 		} else if (!pclc_smcd_v2_ext) {
1571 			ini->smcd_version &= ~SMC_V2;
1572 			rc = SMC_CLC_DECL_NOV2DEXT;
1573 		} else if (!pclc_v2_ext->hdr.eid_cnt &&
1574 			   !pclc_v2_ext->hdr.flag.seid) {
1575 			ini->smcd_version &= ~SMC_V2;
1576 			rc = SMC_CLC_DECL_NOUEID;
1577 		}
1578 	}
1579 	if (ini->smcr_version & SMC_V2) {
1580 		if (!pclc_v2_ext->hdr.eid_cnt) {
1581 			ini->smcr_version &= ~SMC_V2;
1582 			rc = SMC_CLC_DECL_NOUEID;
1583 		}
1584 	}
1585 
1586 out:
1587 	if (!ini->smcd_version && !ini->smcr_version)
1588 		return rc;
1589 
1590 	return 0;
1591 }
1592 
1593 /* listen worker: check prefixes */
1594 static int smc_listen_prfx_check(struct smc_sock *new_smc,
1595 				 struct smc_clc_msg_proposal *pclc)
1596 {
1597 	struct smc_clc_msg_proposal_prefix *pclc_prfx;
1598 	struct socket *newclcsock = new_smc->clcsock;
1599 
1600 	if (pclc->hdr.typev1 == SMC_TYPE_N)
1601 		return 0;
1602 	pclc_prfx = smc_clc_proposal_get_prefix(pclc);
1603 	if (smc_clc_prfx_match(newclcsock, pclc_prfx))
1604 		return SMC_CLC_DECL_DIFFPREFIX;
1605 
1606 	return 0;
1607 }
1608 
1609 /* listen worker: initialize connection and buffers */
1610 static int smc_listen_rdma_init(struct smc_sock *new_smc,
1611 				struct smc_init_info *ini)
1612 {
1613 	int rc;
1614 
1615 	/* allocate connection / link group */
1616 	rc = smc_conn_create(new_smc, ini);
1617 	if (rc)
1618 		return rc;
1619 
1620 	/* create send buffer and rmb */
1621 	if (smc_buf_create(new_smc, false))
1622 		return SMC_CLC_DECL_MEM;
1623 
1624 	return 0;
1625 }
1626 
1627 /* listen worker: initialize connection and buffers for SMC-D */
1628 static int smc_listen_ism_init(struct smc_sock *new_smc,
1629 			       struct smc_init_info *ini)
1630 {
1631 	int rc;
1632 
1633 	rc = smc_conn_create(new_smc, ini);
1634 	if (rc)
1635 		return rc;
1636 
1637 	/* Create send and receive buffers */
1638 	rc = smc_buf_create(new_smc, true);
1639 	if (rc) {
1640 		smc_conn_abort(new_smc, ini->first_contact_local);
1641 		return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
1642 					 SMC_CLC_DECL_MEM;
1643 	}
1644 
1645 	return 0;
1646 }
1647 
1648 static bool smc_is_already_selected(struct smcd_dev *smcd,
1649 				    struct smc_init_info *ini,
1650 				    int matches)
1651 {
1652 	int i;
1653 
1654 	for (i = 0; i < matches; i++)
1655 		if (smcd == ini->ism_dev[i])
1656 			return true;
1657 
1658 	return false;
1659 }
1660 
1661 /* check for ISM devices matching proposed ISM devices */
1662 static void smc_check_ism_v2_match(struct smc_init_info *ini,
1663 				   u16 proposed_chid, u64 proposed_gid,
1664 				   unsigned int *matches)
1665 {
1666 	struct smcd_dev *smcd;
1667 
1668 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1669 		if (smcd->going_away)
1670 			continue;
1671 		if (smc_is_already_selected(smcd, ini, *matches))
1672 			continue;
1673 		if (smc_ism_get_chid(smcd) == proposed_chid &&
1674 		    !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
1675 			ini->ism_peer_gid[*matches] = proposed_gid;
1676 			ini->ism_dev[*matches] = smcd;
1677 			(*matches)++;
1678 			break;
1679 		}
1680 	}
1681 }
1682 
1683 static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
1684 {
1685 	if (!ini->rc)
1686 		ini->rc = rc;
1687 }
1688 
1689 static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
1690 					struct smc_clc_msg_proposal *pclc,
1691 					struct smc_init_info *ini)
1692 {
1693 	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
1694 	struct smc_clc_v2_extension *smc_v2_ext;
1695 	struct smc_clc_msg_smcd *pclc_smcd;
1696 	unsigned int matches = 0;
1697 	u8 smcd_version;
1698 	u8 *eid = NULL;
1699 	int i, rc;
1700 
1701 	if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
1702 		goto not_found;
1703 
1704 	pclc_smcd = smc_get_clc_msg_smcd(pclc);
1705 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
1706 	smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
1707 
1708 	mutex_lock(&smcd_dev_list.mutex);
1709 	if (pclc_smcd->ism.chid)
1710 		/* check for ISM device matching proposed native ISM device */
1711 		smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
1712 				       ntohll(pclc_smcd->ism.gid), &matches);
1713 	for (i = 1; i <= smc_v2_ext->hdr.ism_gid_cnt; i++) {
1714 		/* check for ISM devices matching proposed non-native ISM
1715 		 * devices
1716 		 */
1717 		smc_check_ism_v2_match(ini,
1718 				       ntohs(smcd_v2_ext->gidchid[i - 1].chid),
1719 				       ntohll(smcd_v2_ext->gidchid[i - 1].gid),
1720 				       &matches);
1721 	}
1722 	mutex_unlock(&smcd_dev_list.mutex);
1723 
1724 	if (!ini->ism_dev[0]) {
1725 		smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
1726 		goto not_found;
1727 	}
1728 
1729 	smc_ism_get_system_eid(&eid);
1730 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
1731 			       smcd_v2_ext->system_eid, eid))
1732 		goto not_found;
1733 
1734 	/* separate - outside the smcd_dev_list.lock */
1735 	smcd_version = ini->smcd_version;
1736 	for (i = 0; i < matches; i++) {
1737 		ini->smcd_version = SMC_V2;
1738 		ini->is_smcd = true;
1739 		ini->ism_selected = i;
1740 		rc = smc_listen_ism_init(new_smc, ini);
1741 		if (rc) {
1742 			smc_find_ism_store_rc(rc, ini);
1743 			/* try next active ISM device */
1744 			continue;
1745 		}
1746 		return; /* matching and usable V2 ISM device found */
1747 	}
1748 	/* no V2 ISM device could be initialized */
1749 	ini->smcd_version = smcd_version;	/* restore original value */
1750 	ini->negotiated_eid[0] = 0;
1751 
1752 not_found:
1753 	ini->smcd_version &= ~SMC_V2;
1754 	ini->ism_dev[0] = NULL;
1755 	ini->is_smcd = false;
1756 }
1757 
1758 static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
1759 					struct smc_clc_msg_proposal *pclc,
1760 					struct smc_init_info *ini)
1761 {
1762 	struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
1763 	int rc = 0;
1764 
1765 	/* check if ISM V1 is available */
1766 	if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
1767 		goto not_found;
1768 	ini->is_smcd = true; /* prepare ISM check */
1769 	ini->ism_peer_gid[0] = ntohll(pclc_smcd->ism.gid);
1770 	rc = smc_find_ism_device(new_smc, ini);
1771 	if (rc)
1772 		goto not_found;
1773 	ini->ism_selected = 0;
1774 	rc = smc_listen_ism_init(new_smc, ini);
1775 	if (!rc)
1776 		return;		/* V1 ISM device found */
1777 
1778 not_found:
1779 	smc_find_ism_store_rc(rc, ini);
1780 	ini->smcd_version &= ~SMC_V1;
1781 	ini->ism_dev[0] = NULL;
1782 	ini->is_smcd = false;
1783 }
1784 
1785 /* listen worker: register buffers */
1786 static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
1787 {
1788 	struct smc_connection *conn = &new_smc->conn;
1789 
1790 	if (!local_first) {
1791 		if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
1792 			return SMC_CLC_DECL_ERR_REGRMB;
1793 	}
1794 	smc_rmb_sync_sg_for_device(&new_smc->conn);
1795 
1796 	return 0;
1797 }
1798 
1799 static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
1800 					 struct smc_clc_msg_proposal *pclc,
1801 					 struct smc_init_info *ini)
1802 {
1803 	struct smc_clc_v2_extension *smc_v2_ext;
1804 	u8 smcr_version;
1805 	int rc;
1806 
1807 	if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
1808 		goto not_found;
1809 
1810 	smc_v2_ext = smc_get_clc_v2_ext(pclc);
1811 	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
1812 		goto not_found;
1813 
1814 	/* prepare RDMA check */
1815 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
1816 	memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
1817 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
1818 	ini->check_smcrv2 = true;
1819 	ini->smcrv2.clc_sk = new_smc->clcsock->sk;
1820 	ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
1821 	ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
1822 	rc = smc_find_rdma_device(new_smc, ini);
1823 	if (rc) {
1824 		smc_find_ism_store_rc(rc, ini);
1825 		goto not_found;
1826 	}
1827 	if (!ini->smcrv2.uses_gateway)
1828 		memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
1829 
1830 	smcr_version = ini->smcr_version;
1831 	ini->smcr_version = SMC_V2;
1832 	rc = smc_listen_rdma_init(new_smc, ini);
1833 	if (!rc)
1834 		rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
1835 	if (!rc)
1836 		return;
1837 	ini->smcr_version = smcr_version;
1838 	smc_find_ism_store_rc(rc, ini);
1839 
1840 not_found:
1841 	ini->smcr_version &= ~SMC_V2;
1842 	ini->check_smcrv2 = false;
1843 }
1844 
1845 static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
1846 					struct smc_clc_msg_proposal *pclc,
1847 					struct smc_init_info *ini)
1848 {
1849 	int rc;
1850 
1851 	if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
1852 		return SMC_CLC_DECL_NOSMCDEV;
1853 
1854 	/* prepare RDMA check */
1855 	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
1856 	memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
1857 	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
1858 	rc = smc_find_rdma_device(new_smc, ini);
1859 	if (rc) {
1860 		/* no RDMA device found */
1861 		return SMC_CLC_DECL_NOSMCDEV;
1862 	}
1863 	rc = smc_listen_rdma_init(new_smc, ini);
1864 	if (rc)
1865 		return rc;
1866 	return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
1867 }
1868 
1869 /* determine the local device matching to proposal */
1870 static int smc_listen_find_device(struct smc_sock *new_smc,
1871 				  struct smc_clc_msg_proposal *pclc,
1872 				  struct smc_init_info *ini)
1873 {
1874 	int prfx_rc;
1875 
1876 	/* check for ISM device matching V2 proposed device */
1877 	smc_find_ism_v2_device_serv(new_smc, pclc, ini);
1878 	if (ini->ism_dev[0])
1879 		return 0;
1880 
1881 	/* check for matching IP prefix and subnet length (V1) */
1882 	prfx_rc = smc_listen_prfx_check(new_smc, pclc);
1883 	if (prfx_rc)
1884 		smc_find_ism_store_rc(prfx_rc, ini);
1885 
1886 	/* get vlan id from IP device */
1887 	if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
1888 		return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
1889 
1890 	/* check for ISM device matching V1 proposed device */
1891 	if (!prfx_rc)
1892 		smc_find_ism_v1_device_serv(new_smc, pclc, ini);
1893 	if (ini->ism_dev[0])
1894 		return 0;
1895 
1896 	if (!smcr_indicated(pclc->hdr.typev1) &&
1897 	    !smcr_indicated(pclc->hdr.typev2))
1898 		/* skip RDMA and decline */
1899 		return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
1900 
1901 	/* check if RDMA V2 is available */
1902 	smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
1903 	if (ini->smcrv2.ib_dev_v2)
1904 		return 0;
1905 
1906 	/* check if RDMA V1 is available */
1907 	if (!prfx_rc) {
1908 		int rc;
1909 
1910 		rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
1911 		smc_find_ism_store_rc(rc, ini);
1912 		return (!rc) ? 0 : ini->rc;
1913 	}
1914 	return SMC_CLC_DECL_NOSMCDEV;
1915 }
1916 
1917 /* listen worker: finish RDMA setup */
1918 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
1919 				  struct smc_clc_msg_accept_confirm *cclc,
1920 				  bool local_first,
1921 				  struct smc_init_info *ini)
1922 {
1923 	struct smc_link *link = new_smc->conn.lnk;
1924 	int reason_code = 0;
1925 
1926 	if (local_first)
1927 		smc_link_save_peer_info(link, cclc, ini);
1928 
1929 	if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
1930 		return SMC_CLC_DECL_ERR_RTOK;
1931 
1932 	if (local_first) {
1933 		if (smc_ib_ready_link(link))
1934 			return SMC_CLC_DECL_ERR_RDYLNK;
1935 		/* QP confirmation over RoCE fabric */
1936 		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1937 		reason_code = smcr_serv_conf_first_link(new_smc);
1938 		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1939 	}
1940 	return reason_code;
1941 }
1942 
1943 /* setup for connection of server */
1944 static void smc_listen_work(struct work_struct *work)
1945 {
1946 	struct smc_sock *new_smc = container_of(work, struct smc_sock,
1947 						smc_listen_work);
1948 	struct socket *newclcsock = new_smc->clcsock;
1949 	struct smc_clc_msg_accept_confirm *cclc;
1950 	struct smc_clc_msg_proposal_area *buf;
1951 	struct smc_clc_msg_proposal *pclc;
1952 	struct smc_init_info *ini = NULL;
1953 	u8 proposal_version = SMC_V1;
1954 	u8 accept_version;
1955 	int rc = 0;
1956 
1957 	if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
1958 		return smc_listen_out_err(new_smc);
1959 
1960 	if (new_smc->use_fallback) {
1961 		smc_listen_out_connected(new_smc);
1962 		return;
1963 	}
1964 
1965 	/* check if peer is smc capable */
1966 	if (!tcp_sk(newclcsock->sk)->syn_smc) {
1967 		smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
1968 		smc_listen_out_connected(new_smc);
1969 		return;
1970 	}
1971 
1972 	/* do inband token exchange -
1973 	 * wait for and receive SMC Proposal CLC message
1974 	 */
1975 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
1976 	if (!buf) {
1977 		rc = SMC_CLC_DECL_MEM;
1978 		goto out_decl;
1979 	}
1980 	pclc = (struct smc_clc_msg_proposal *)buf;
1981 	rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
1982 			      SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
1983 	if (rc)
1984 		goto out_decl;
1985 
1986 	if (pclc->hdr.version > SMC_V1)
1987 		proposal_version = SMC_V2;
1988 
1989 	/* IPSec connections opt out of SMC optimizations */
1990 	if (using_ipsec(new_smc)) {
1991 		rc = SMC_CLC_DECL_IPSEC;
1992 		goto out_decl;
1993 	}
1994 
1995 	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1996 	if (!ini) {
1997 		rc = SMC_CLC_DECL_MEM;
1998 		goto out_decl;
1999 	}
2000 
2001 	/* initial version checking */
2002 	rc = smc_listen_v2_check(new_smc, pclc, ini);
2003 	if (rc)
2004 		goto out_decl;
2005 
2006 	mutex_lock(&smc_server_lgr_pending);
2007 	smc_close_init(new_smc);
2008 	smc_rx_init(new_smc);
2009 	smc_tx_init(new_smc);
2010 
2011 	/* determine ISM or RoCE device used for connection */
2012 	rc = smc_listen_find_device(new_smc, pclc, ini);
2013 	if (rc)
2014 		goto out_unlock;
2015 
2016 	/* send SMC Accept CLC message */
2017 	accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2018 	rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2019 				 accept_version, ini->negotiated_eid);
2020 	if (rc)
2021 		goto out_unlock;
2022 
2023 	/* SMC-D does not need this lock any more */
2024 	if (ini->is_smcd)
2025 		mutex_unlock(&smc_server_lgr_pending);
2026 
2027 	/* receive SMC Confirm CLC message */
2028 	memset(buf, 0, sizeof(*buf));
2029 	cclc = (struct smc_clc_msg_accept_confirm *)buf;
2030 	rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2031 			      SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2032 	if (rc) {
2033 		if (!ini->is_smcd)
2034 			goto out_unlock;
2035 		goto out_decl;
2036 	}
2037 
2038 	/* finish worker */
2039 	if (!ini->is_smcd) {
2040 		rc = smc_listen_rdma_finish(new_smc, cclc,
2041 					    ini->first_contact_local, ini);
2042 		if (rc)
2043 			goto out_unlock;
2044 		mutex_unlock(&smc_server_lgr_pending);
2045 	}
2046 	smc_conn_save_peer_info(new_smc, cclc);
2047 	smc_listen_out_connected(new_smc);
2048 	SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2049 	goto out_free;
2050 
2051 out_unlock:
2052 	mutex_unlock(&smc_server_lgr_pending);
2053 out_decl:
2054 	smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2055 			   proposal_version);
2056 out_free:
2057 	kfree(ini);
2058 	kfree(buf);
2059 }
2060 
2061 static void smc_tcp_listen_work(struct work_struct *work)
2062 {
2063 	struct smc_sock *lsmc = container_of(work, struct smc_sock,
2064 					     tcp_listen_work);
2065 	struct sock *lsk = &lsmc->sk;
2066 	struct smc_sock *new_smc;
2067 	int rc = 0;
2068 
2069 	lock_sock(lsk);
2070 	while (lsk->sk_state == SMC_LISTEN) {
2071 		rc = smc_clcsock_accept(lsmc, &new_smc);
2072 		if (rc) /* clcsock accept queue empty or error */
2073 			goto out;
2074 		if (!new_smc)
2075 			continue;
2076 
2077 		new_smc->listen_smc = lsmc;
2078 		new_smc->use_fallback = lsmc->use_fallback;
2079 		new_smc->fallback_rsn = lsmc->fallback_rsn;
2080 		sock_hold(lsk); /* sock_put in smc_listen_work */
2081 		INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2082 		smc_copy_sock_settings_to_smc(new_smc);
2083 		new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
2084 		new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
2085 		sock_hold(&new_smc->sk); /* sock_put in passive closing */
2086 		if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2087 			sock_put(&new_smc->sk);
2088 	}
2089 
2090 out:
2091 	release_sock(lsk);
2092 	sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2093 }
2094 
2095 static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2096 {
2097 	struct smc_sock *lsmc;
2098 
2099 	lsmc = (struct smc_sock *)
2100 	       ((uintptr_t)listen_clcsock->sk_user_data & ~SK_USER_DATA_NOCOPY);
2101 	if (!lsmc)
2102 		return;
2103 	lsmc->clcsk_data_ready(listen_clcsock);
2104 	if (lsmc->sk.sk_state == SMC_LISTEN) {
2105 		sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2106 		if (!queue_work(smc_hs_wq, &lsmc->tcp_listen_work))
2107 			sock_put(&lsmc->sk);
2108 	}
2109 }
2110 
2111 static int smc_listen(struct socket *sock, int backlog)
2112 {
2113 	struct sock *sk = sock->sk;
2114 	struct smc_sock *smc;
2115 	int rc;
2116 
2117 	smc = smc_sk(sk);
2118 	lock_sock(sk);
2119 
2120 	rc = -EINVAL;
2121 	if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2122 	    smc->connect_nonblock)
2123 		goto out;
2124 
2125 	rc = 0;
2126 	if (sk->sk_state == SMC_LISTEN) {
2127 		sk->sk_max_ack_backlog = backlog;
2128 		goto out;
2129 	}
2130 	/* some socket options are handled in core, so we could not apply
2131 	 * them to the clc socket -- copy smc socket options to clc socket
2132 	 */
2133 	smc_copy_sock_settings_to_clc(smc);
2134 	if (!smc->use_fallback)
2135 		tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2136 
2137 	/* save original sk_data_ready function and establish
2138 	 * smc-specific sk_data_ready function
2139 	 */
2140 	smc->clcsk_data_ready = smc->clcsock->sk->sk_data_ready;
2141 	smc->clcsock->sk->sk_data_ready = smc_clcsock_data_ready;
2142 	smc->clcsock->sk->sk_user_data =
2143 		(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2144 	rc = kernel_listen(smc->clcsock, backlog);
2145 	if (rc) {
2146 		smc->clcsock->sk->sk_data_ready = smc->clcsk_data_ready;
2147 		goto out;
2148 	}
2149 	sk->sk_max_ack_backlog = backlog;
2150 	sk->sk_ack_backlog = 0;
2151 	sk->sk_state = SMC_LISTEN;
2152 
2153 out:
2154 	release_sock(sk);
2155 	return rc;
2156 }
2157 
2158 static int smc_accept(struct socket *sock, struct socket *new_sock,
2159 		      int flags, bool kern)
2160 {
2161 	struct sock *sk = sock->sk, *nsk;
2162 	DECLARE_WAITQUEUE(wait, current);
2163 	struct smc_sock *lsmc;
2164 	long timeo;
2165 	int rc = 0;
2166 
2167 	lsmc = smc_sk(sk);
2168 	sock_hold(sk); /* sock_put below */
2169 	lock_sock(sk);
2170 
2171 	if (lsmc->sk.sk_state != SMC_LISTEN) {
2172 		rc = -EINVAL;
2173 		release_sock(sk);
2174 		goto out;
2175 	}
2176 
2177 	/* Wait for an incoming connection */
2178 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2179 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
2180 	while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2181 		set_current_state(TASK_INTERRUPTIBLE);
2182 		if (!timeo) {
2183 			rc = -EAGAIN;
2184 			break;
2185 		}
2186 		release_sock(sk);
2187 		timeo = schedule_timeout(timeo);
2188 		/* wakeup by sk_data_ready in smc_listen_work() */
2189 		sched_annotate_sleep();
2190 		lock_sock(sk);
2191 		if (signal_pending(current)) {
2192 			rc = sock_intr_errno(timeo);
2193 			break;
2194 		}
2195 	}
2196 	set_current_state(TASK_RUNNING);
2197 	remove_wait_queue(sk_sleep(sk), &wait);
2198 
2199 	if (!rc)
2200 		rc = sock_error(nsk);
2201 	release_sock(sk);
2202 	if (rc)
2203 		goto out;
2204 
2205 	if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
2206 		/* wait till data arrives on the socket */
2207 		timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2208 								MSEC_PER_SEC);
2209 		if (smc_sk(nsk)->use_fallback) {
2210 			struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2211 
2212 			lock_sock(clcsk);
2213 			if (skb_queue_empty(&clcsk->sk_receive_queue))
2214 				sk_wait_data(clcsk, &timeo, NULL);
2215 			release_sock(clcsk);
2216 		} else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2217 			lock_sock(nsk);
2218 			smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2219 			release_sock(nsk);
2220 		}
2221 	}
2222 
2223 out:
2224 	sock_put(sk); /* sock_hold above */
2225 	return rc;
2226 }
2227 
2228 static int smc_getname(struct socket *sock, struct sockaddr *addr,
2229 		       int peer)
2230 {
2231 	struct smc_sock *smc;
2232 
2233 	if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2234 	    (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2235 		return -ENOTCONN;
2236 
2237 	smc = smc_sk(sock->sk);
2238 
2239 	return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2240 }
2241 
2242 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2243 {
2244 	struct sock *sk = sock->sk;
2245 	struct smc_sock *smc;
2246 	int rc = -EPIPE;
2247 
2248 	smc = smc_sk(sk);
2249 	lock_sock(sk);
2250 	if ((sk->sk_state != SMC_ACTIVE) &&
2251 	    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2252 	    (sk->sk_state != SMC_INIT))
2253 		goto out;
2254 
2255 	if (msg->msg_flags & MSG_FASTOPEN) {
2256 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2257 			smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2258 		} else {
2259 			rc = -EINVAL;
2260 			goto out;
2261 		}
2262 	}
2263 
2264 	if (smc->use_fallback) {
2265 		rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2266 	} else {
2267 		rc = smc_tx_sendmsg(smc, msg, len);
2268 		SMC_STAT_TX_PAYLOAD(smc, len, rc);
2269 	}
2270 out:
2271 	release_sock(sk);
2272 	return rc;
2273 }
2274 
2275 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2276 		       int flags)
2277 {
2278 	struct sock *sk = sock->sk;
2279 	struct smc_sock *smc;
2280 	int rc = -ENOTCONN;
2281 
2282 	smc = smc_sk(sk);
2283 	lock_sock(sk);
2284 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2285 		/* socket was connected before, no more data to read */
2286 		rc = 0;
2287 		goto out;
2288 	}
2289 	if ((sk->sk_state == SMC_INIT) ||
2290 	    (sk->sk_state == SMC_LISTEN) ||
2291 	    (sk->sk_state == SMC_CLOSED))
2292 		goto out;
2293 
2294 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2295 		rc = 0;
2296 		goto out;
2297 	}
2298 
2299 	if (smc->use_fallback) {
2300 		rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2301 	} else {
2302 		msg->msg_namelen = 0;
2303 		rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2304 		SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2305 	}
2306 
2307 out:
2308 	release_sock(sk);
2309 	return rc;
2310 }
2311 
2312 static __poll_t smc_accept_poll(struct sock *parent)
2313 {
2314 	struct smc_sock *isk = smc_sk(parent);
2315 	__poll_t mask = 0;
2316 
2317 	spin_lock(&isk->accept_q_lock);
2318 	if (!list_empty(&isk->accept_q))
2319 		mask = EPOLLIN | EPOLLRDNORM;
2320 	spin_unlock(&isk->accept_q_lock);
2321 
2322 	return mask;
2323 }
2324 
2325 static __poll_t smc_poll(struct file *file, struct socket *sock,
2326 			     poll_table *wait)
2327 {
2328 	struct sock *sk = sock->sk;
2329 	struct smc_sock *smc;
2330 	__poll_t mask = 0;
2331 
2332 	if (!sk)
2333 		return EPOLLNVAL;
2334 
2335 	smc = smc_sk(sock->sk);
2336 	if (smc->use_fallback) {
2337 		/* delegate to CLC child sock */
2338 		mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2339 		sk->sk_err = smc->clcsock->sk->sk_err;
2340 	} else {
2341 		if (sk->sk_state != SMC_CLOSED)
2342 			sock_poll_wait(file, sock, wait);
2343 		if (sk->sk_err)
2344 			mask |= EPOLLERR;
2345 		if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2346 		    (sk->sk_state == SMC_CLOSED))
2347 			mask |= EPOLLHUP;
2348 		if (sk->sk_state == SMC_LISTEN) {
2349 			/* woken up by sk_data_ready in smc_listen_work() */
2350 			mask |= smc_accept_poll(sk);
2351 		} else if (smc->use_fallback) { /* as result of connect_work()*/
2352 			mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2353 							   wait);
2354 			sk->sk_err = smc->clcsock->sk->sk_err;
2355 		} else {
2356 			if ((sk->sk_state != SMC_INIT &&
2357 			     atomic_read(&smc->conn.sndbuf_space)) ||
2358 			    sk->sk_shutdown & SEND_SHUTDOWN) {
2359 				mask |= EPOLLOUT | EPOLLWRNORM;
2360 			} else {
2361 				sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2362 				set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2363 			}
2364 			if (atomic_read(&smc->conn.bytes_to_rcv))
2365 				mask |= EPOLLIN | EPOLLRDNORM;
2366 			if (sk->sk_shutdown & RCV_SHUTDOWN)
2367 				mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2368 			if (sk->sk_state == SMC_APPCLOSEWAIT1)
2369 				mask |= EPOLLIN;
2370 			if (smc->conn.urg_state == SMC_URG_VALID)
2371 				mask |= EPOLLPRI;
2372 		}
2373 	}
2374 
2375 	return mask;
2376 }
2377 
2378 static int smc_shutdown(struct socket *sock, int how)
2379 {
2380 	struct sock *sk = sock->sk;
2381 	bool do_shutdown = true;
2382 	struct smc_sock *smc;
2383 	int rc = -EINVAL;
2384 	int old_state;
2385 	int rc1 = 0;
2386 
2387 	smc = smc_sk(sk);
2388 
2389 	if ((how < SHUT_RD) || (how > SHUT_RDWR))
2390 		return rc;
2391 
2392 	lock_sock(sk);
2393 
2394 	rc = -ENOTCONN;
2395 	if ((sk->sk_state != SMC_ACTIVE) &&
2396 	    (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2397 	    (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2398 	    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2399 	    (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2400 	    (sk->sk_state != SMC_APPFINCLOSEWAIT))
2401 		goto out;
2402 	if (smc->use_fallback) {
2403 		rc = kernel_sock_shutdown(smc->clcsock, how);
2404 		sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2405 		if (sk->sk_shutdown == SHUTDOWN_MASK)
2406 			sk->sk_state = SMC_CLOSED;
2407 		goto out;
2408 	}
2409 	switch (how) {
2410 	case SHUT_RDWR:		/* shutdown in both directions */
2411 		old_state = sk->sk_state;
2412 		rc = smc_close_active(smc);
2413 		if (old_state == SMC_ACTIVE &&
2414 		    sk->sk_state == SMC_PEERCLOSEWAIT1)
2415 			do_shutdown = false;
2416 		break;
2417 	case SHUT_WR:
2418 		rc = smc_close_shutdown_write(smc);
2419 		break;
2420 	case SHUT_RD:
2421 		rc = 0;
2422 		/* nothing more to do because peer is not involved */
2423 		break;
2424 	}
2425 	if (do_shutdown && smc->clcsock)
2426 		rc1 = kernel_sock_shutdown(smc->clcsock, how);
2427 	/* map sock_shutdown_cmd constants to sk_shutdown value range */
2428 	sk->sk_shutdown |= how + 1;
2429 
2430 out:
2431 	release_sock(sk);
2432 	return rc ? rc : rc1;
2433 }
2434 
2435 static int smc_setsockopt(struct socket *sock, int level, int optname,
2436 			  sockptr_t optval, unsigned int optlen)
2437 {
2438 	struct sock *sk = sock->sk;
2439 	struct smc_sock *smc;
2440 	int val, rc;
2441 
2442 	if (level == SOL_TCP && optname == TCP_ULP)
2443 		return -EOPNOTSUPP;
2444 
2445 	smc = smc_sk(sk);
2446 
2447 	/* generic setsockopts reaching us here always apply to the
2448 	 * CLC socket
2449 	 */
2450 	if (unlikely(!smc->clcsock->ops->setsockopt))
2451 		rc = -EOPNOTSUPP;
2452 	else
2453 		rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
2454 						   optval, optlen);
2455 	if (smc->clcsock->sk->sk_err) {
2456 		sk->sk_err = smc->clcsock->sk->sk_err;
2457 		sk_error_report(sk);
2458 	}
2459 
2460 	if (optlen < sizeof(int))
2461 		return -EINVAL;
2462 	if (copy_from_sockptr(&val, optval, sizeof(int)))
2463 		return -EFAULT;
2464 
2465 	lock_sock(sk);
2466 	if (rc || smc->use_fallback)
2467 		goto out;
2468 	switch (optname) {
2469 	case TCP_FASTOPEN:
2470 	case TCP_FASTOPEN_CONNECT:
2471 	case TCP_FASTOPEN_KEY:
2472 	case TCP_FASTOPEN_NO_COOKIE:
2473 		/* option not supported by SMC */
2474 		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2475 			smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2476 		} else {
2477 			rc = -EINVAL;
2478 		}
2479 		break;
2480 	case TCP_NODELAY:
2481 		if (sk->sk_state != SMC_INIT &&
2482 		    sk->sk_state != SMC_LISTEN &&
2483 		    sk->sk_state != SMC_CLOSED) {
2484 			if (val) {
2485 				SMC_STAT_INC(smc, ndly_cnt);
2486 				mod_delayed_work(smc->conn.lgr->tx_wq,
2487 						 &smc->conn.tx_work, 0);
2488 			}
2489 		}
2490 		break;
2491 	case TCP_CORK:
2492 		if (sk->sk_state != SMC_INIT &&
2493 		    sk->sk_state != SMC_LISTEN &&
2494 		    sk->sk_state != SMC_CLOSED) {
2495 			if (!val) {
2496 				SMC_STAT_INC(smc, cork_cnt);
2497 				mod_delayed_work(smc->conn.lgr->tx_wq,
2498 						 &smc->conn.tx_work, 0);
2499 			}
2500 		}
2501 		break;
2502 	case TCP_DEFER_ACCEPT:
2503 		smc->sockopt_defer_accept = val;
2504 		break;
2505 	default:
2506 		break;
2507 	}
2508 out:
2509 	release_sock(sk);
2510 
2511 	return rc;
2512 }
2513 
2514 static int smc_getsockopt(struct socket *sock, int level, int optname,
2515 			  char __user *optval, int __user *optlen)
2516 {
2517 	struct smc_sock *smc;
2518 
2519 	smc = smc_sk(sock->sk);
2520 	/* socket options apply to the CLC socket */
2521 	if (unlikely(!smc->clcsock->ops->getsockopt))
2522 		return -EOPNOTSUPP;
2523 	return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
2524 					     optval, optlen);
2525 }
2526 
2527 static int smc_ioctl(struct socket *sock, unsigned int cmd,
2528 		     unsigned long arg)
2529 {
2530 	union smc_host_cursor cons, urg;
2531 	struct smc_connection *conn;
2532 	struct smc_sock *smc;
2533 	int answ;
2534 
2535 	smc = smc_sk(sock->sk);
2536 	conn = &smc->conn;
2537 	lock_sock(&smc->sk);
2538 	if (smc->use_fallback) {
2539 		if (!smc->clcsock) {
2540 			release_sock(&smc->sk);
2541 			return -EBADF;
2542 		}
2543 		answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
2544 		release_sock(&smc->sk);
2545 		return answ;
2546 	}
2547 	switch (cmd) {
2548 	case SIOCINQ: /* same as FIONREAD */
2549 		if (smc->sk.sk_state == SMC_LISTEN) {
2550 			release_sock(&smc->sk);
2551 			return -EINVAL;
2552 		}
2553 		if (smc->sk.sk_state == SMC_INIT ||
2554 		    smc->sk.sk_state == SMC_CLOSED)
2555 			answ = 0;
2556 		else
2557 			answ = atomic_read(&smc->conn.bytes_to_rcv);
2558 		break;
2559 	case SIOCOUTQ:
2560 		/* output queue size (not send + not acked) */
2561 		if (smc->sk.sk_state == SMC_LISTEN) {
2562 			release_sock(&smc->sk);
2563 			return -EINVAL;
2564 		}
2565 		if (smc->sk.sk_state == SMC_INIT ||
2566 		    smc->sk.sk_state == SMC_CLOSED)
2567 			answ = 0;
2568 		else
2569 			answ = smc->conn.sndbuf_desc->len -
2570 					atomic_read(&smc->conn.sndbuf_space);
2571 		break;
2572 	case SIOCOUTQNSD:
2573 		/* output queue size (not send only) */
2574 		if (smc->sk.sk_state == SMC_LISTEN) {
2575 			release_sock(&smc->sk);
2576 			return -EINVAL;
2577 		}
2578 		if (smc->sk.sk_state == SMC_INIT ||
2579 		    smc->sk.sk_state == SMC_CLOSED)
2580 			answ = 0;
2581 		else
2582 			answ = smc_tx_prepared_sends(&smc->conn);
2583 		break;
2584 	case SIOCATMARK:
2585 		if (smc->sk.sk_state == SMC_LISTEN) {
2586 			release_sock(&smc->sk);
2587 			return -EINVAL;
2588 		}
2589 		if (smc->sk.sk_state == SMC_INIT ||
2590 		    smc->sk.sk_state == SMC_CLOSED) {
2591 			answ = 0;
2592 		} else {
2593 			smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
2594 			smc_curs_copy(&urg, &conn->urg_curs, conn);
2595 			answ = smc_curs_diff(conn->rmb_desc->len,
2596 					     &cons, &urg) == 1;
2597 		}
2598 		break;
2599 	default:
2600 		release_sock(&smc->sk);
2601 		return -ENOIOCTLCMD;
2602 	}
2603 	release_sock(&smc->sk);
2604 
2605 	return put_user(answ, (int __user *)arg);
2606 }
2607 
2608 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
2609 			    int offset, size_t size, int flags)
2610 {
2611 	struct sock *sk = sock->sk;
2612 	struct smc_sock *smc;
2613 	int rc = -EPIPE;
2614 
2615 	smc = smc_sk(sk);
2616 	lock_sock(sk);
2617 	if (sk->sk_state != SMC_ACTIVE) {
2618 		release_sock(sk);
2619 		goto out;
2620 	}
2621 	release_sock(sk);
2622 	if (smc->use_fallback) {
2623 		rc = kernel_sendpage(smc->clcsock, page, offset,
2624 				     size, flags);
2625 	} else {
2626 		SMC_STAT_INC(smc, sendpage_cnt);
2627 		rc = sock_no_sendpage(sock, page, offset, size, flags);
2628 	}
2629 
2630 out:
2631 	return rc;
2632 }
2633 
2634 /* Map the affected portions of the rmbe into an spd, note the number of bytes
2635  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
2636  * updates till whenever a respective page has been fully processed.
2637  * Note that subsequent recv() calls have to wait till all splice() processing
2638  * completed.
2639  */
2640 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
2641 			       struct pipe_inode_info *pipe, size_t len,
2642 			       unsigned int flags)
2643 {
2644 	struct sock *sk = sock->sk;
2645 	struct smc_sock *smc;
2646 	int rc = -ENOTCONN;
2647 
2648 	smc = smc_sk(sk);
2649 	lock_sock(sk);
2650 	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2651 		/* socket was connected before, no more data to read */
2652 		rc = 0;
2653 		goto out;
2654 	}
2655 	if (sk->sk_state == SMC_INIT ||
2656 	    sk->sk_state == SMC_LISTEN ||
2657 	    sk->sk_state == SMC_CLOSED)
2658 		goto out;
2659 
2660 	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2661 		rc = 0;
2662 		goto out;
2663 	}
2664 
2665 	if (smc->use_fallback) {
2666 		rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
2667 						    pipe, len, flags);
2668 	} else {
2669 		if (*ppos) {
2670 			rc = -ESPIPE;
2671 			goto out;
2672 		}
2673 		if (flags & SPLICE_F_NONBLOCK)
2674 			flags = MSG_DONTWAIT;
2675 		else
2676 			flags = 0;
2677 		SMC_STAT_INC(smc, splice_cnt);
2678 		rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
2679 	}
2680 out:
2681 	release_sock(sk);
2682 
2683 	return rc;
2684 }
2685 
2686 /* must look like tcp */
2687 static const struct proto_ops smc_sock_ops = {
2688 	.family		= PF_SMC,
2689 	.owner		= THIS_MODULE,
2690 	.release	= smc_release,
2691 	.bind		= smc_bind,
2692 	.connect	= smc_connect,
2693 	.socketpair	= sock_no_socketpair,
2694 	.accept		= smc_accept,
2695 	.getname	= smc_getname,
2696 	.poll		= smc_poll,
2697 	.ioctl		= smc_ioctl,
2698 	.listen		= smc_listen,
2699 	.shutdown	= smc_shutdown,
2700 	.setsockopt	= smc_setsockopt,
2701 	.getsockopt	= smc_getsockopt,
2702 	.sendmsg	= smc_sendmsg,
2703 	.recvmsg	= smc_recvmsg,
2704 	.mmap		= sock_no_mmap,
2705 	.sendpage	= smc_sendpage,
2706 	.splice_read	= smc_splice_read,
2707 };
2708 
2709 static int __smc_create(struct net *net, struct socket *sock, int protocol,
2710 			int kern, struct socket *clcsock)
2711 {
2712 	int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
2713 	struct smc_sock *smc;
2714 	struct sock *sk;
2715 	int rc;
2716 
2717 	rc = -ESOCKTNOSUPPORT;
2718 	if (sock->type != SOCK_STREAM)
2719 		goto out;
2720 
2721 	rc = -EPROTONOSUPPORT;
2722 	if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
2723 		goto out;
2724 
2725 	rc = -ENOBUFS;
2726 	sock->ops = &smc_sock_ops;
2727 	sk = smc_sock_alloc(net, sock, protocol);
2728 	if (!sk)
2729 		goto out;
2730 
2731 	/* create internal TCP socket for CLC handshake and fallback */
2732 	smc = smc_sk(sk);
2733 	smc->use_fallback = false; /* assume rdma capability first */
2734 	smc->fallback_rsn = 0;
2735 
2736 	rc = 0;
2737 	if (!clcsock) {
2738 		rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
2739 				      &smc->clcsock);
2740 		if (rc) {
2741 			sk_common_release(sk);
2742 			goto out;
2743 		}
2744 	} else {
2745 		smc->clcsock = clcsock;
2746 	}
2747 
2748 	smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);
2749 	smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);
2750 
2751 out:
2752 	return rc;
2753 }
2754 
2755 static int smc_create(struct net *net, struct socket *sock, int protocol,
2756 		      int kern)
2757 {
2758 	return __smc_create(net, sock, protocol, kern, NULL);
2759 }
2760 
2761 static const struct net_proto_family smc_sock_family_ops = {
2762 	.family	= PF_SMC,
2763 	.owner	= THIS_MODULE,
2764 	.create	= smc_create,
2765 };
2766 
2767 static int smc_ulp_init(struct sock *sk)
2768 {
2769 	struct socket *tcp = sk->sk_socket;
2770 	struct net *net = sock_net(sk);
2771 	struct socket *smcsock;
2772 	int protocol, ret;
2773 
2774 	/* only TCP can be replaced */
2775 	if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
2776 	    (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
2777 		return -ESOCKTNOSUPPORT;
2778 	/* don't handle wq now */
2779 	if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
2780 		return -ENOTCONN;
2781 
2782 	if (sk->sk_family == AF_INET)
2783 		protocol = SMCPROTO_SMC;
2784 	else
2785 		protocol = SMCPROTO_SMC6;
2786 
2787 	smcsock = sock_alloc();
2788 	if (!smcsock)
2789 		return -ENFILE;
2790 
2791 	smcsock->type = SOCK_STREAM;
2792 	__module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
2793 	ret = __smc_create(net, smcsock, protocol, 1, tcp);
2794 	if (ret) {
2795 		sock_release(smcsock); /* module_put() which ops won't be NULL */
2796 		return ret;
2797 	}
2798 
2799 	/* replace tcp socket to smc */
2800 	smcsock->file = tcp->file;
2801 	smcsock->file->private_data = smcsock;
2802 	smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
2803 	smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
2804 	tcp->file = NULL;
2805 
2806 	return ret;
2807 }
2808 
2809 static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
2810 			  const gfp_t priority)
2811 {
2812 	struct inet_connection_sock *icsk = inet_csk(newsk);
2813 
2814 	/* don't inherit ulp ops to child when listen */
2815 	icsk->icsk_ulp_ops = NULL;
2816 }
2817 
2818 static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
2819 	.name		= "smc",
2820 	.owner		= THIS_MODULE,
2821 	.init		= smc_ulp_init,
2822 	.clone		= smc_ulp_clone,
2823 };
2824 
2825 unsigned int smc_net_id;
2826 
2827 static __net_init int smc_net_init(struct net *net)
2828 {
2829 	return smc_pnet_net_init(net);
2830 }
2831 
2832 static void __net_exit smc_net_exit(struct net *net)
2833 {
2834 	smc_pnet_net_exit(net);
2835 }
2836 
2837 static __net_init int smc_net_stat_init(struct net *net)
2838 {
2839 	return smc_stats_init(net);
2840 }
2841 
2842 static void __net_exit smc_net_stat_exit(struct net *net)
2843 {
2844 	smc_stats_exit(net);
2845 }
2846 
2847 static struct pernet_operations smc_net_ops = {
2848 	.init = smc_net_init,
2849 	.exit = smc_net_exit,
2850 	.id   = &smc_net_id,
2851 	.size = sizeof(struct smc_net),
2852 };
2853 
2854 static struct pernet_operations smc_net_stat_ops = {
2855 	.init = smc_net_stat_init,
2856 	.exit = smc_net_stat_exit,
2857 };
2858 
2859 static int __init smc_init(void)
2860 {
2861 	int rc;
2862 
2863 	rc = register_pernet_subsys(&smc_net_ops);
2864 	if (rc)
2865 		return rc;
2866 
2867 	rc = register_pernet_subsys(&smc_net_stat_ops);
2868 	if (rc)
2869 		return rc;
2870 
2871 	smc_ism_init();
2872 	smc_clc_init();
2873 
2874 	rc = smc_nl_init();
2875 	if (rc)
2876 		goto out_pernet_subsys;
2877 
2878 	rc = smc_pnet_init();
2879 	if (rc)
2880 		goto out_nl;
2881 
2882 	rc = -ENOMEM;
2883 	smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
2884 	if (!smc_hs_wq)
2885 		goto out_pnet;
2886 
2887 	smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
2888 	if (!smc_close_wq)
2889 		goto out_alloc_hs_wq;
2890 
2891 	rc = smc_core_init();
2892 	if (rc) {
2893 		pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
2894 		goto out_alloc_wqs;
2895 	}
2896 
2897 	rc = smc_llc_init();
2898 	if (rc) {
2899 		pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
2900 		goto out_core;
2901 	}
2902 
2903 	rc = smc_cdc_init();
2904 	if (rc) {
2905 		pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
2906 		goto out_core;
2907 	}
2908 
2909 	rc = proto_register(&smc_proto, 1);
2910 	if (rc) {
2911 		pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
2912 		goto out_core;
2913 	}
2914 
2915 	rc = proto_register(&smc_proto6, 1);
2916 	if (rc) {
2917 		pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
2918 		goto out_proto;
2919 	}
2920 
2921 	rc = sock_register(&smc_sock_family_ops);
2922 	if (rc) {
2923 		pr_err("%s: sock_register fails with %d\n", __func__, rc);
2924 		goto out_proto6;
2925 	}
2926 	INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
2927 	INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
2928 
2929 	rc = smc_ib_register_client();
2930 	if (rc) {
2931 		pr_err("%s: ib_register fails with %d\n", __func__, rc);
2932 		goto out_sock;
2933 	}
2934 
2935 	rc = tcp_register_ulp(&smc_ulp_ops);
2936 	if (rc) {
2937 		pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
2938 		goto out_sock;
2939 	}
2940 
2941 	static_branch_enable(&tcp_have_smc);
2942 	return 0;
2943 
2944 out_sock:
2945 	sock_unregister(PF_SMC);
2946 out_proto6:
2947 	proto_unregister(&smc_proto6);
2948 out_proto:
2949 	proto_unregister(&smc_proto);
2950 out_core:
2951 	smc_core_exit();
2952 out_alloc_wqs:
2953 	destroy_workqueue(smc_close_wq);
2954 out_alloc_hs_wq:
2955 	destroy_workqueue(smc_hs_wq);
2956 out_pnet:
2957 	smc_pnet_exit();
2958 out_nl:
2959 	smc_nl_exit();
2960 out_pernet_subsys:
2961 	unregister_pernet_subsys(&smc_net_ops);
2962 
2963 	return rc;
2964 }
2965 
2966 static void __exit smc_exit(void)
2967 {
2968 	static_branch_disable(&tcp_have_smc);
2969 	tcp_unregister_ulp(&smc_ulp_ops);
2970 	sock_unregister(PF_SMC);
2971 	smc_core_exit();
2972 	smc_ib_unregister_client();
2973 	destroy_workqueue(smc_close_wq);
2974 	destroy_workqueue(smc_hs_wq);
2975 	proto_unregister(&smc_proto6);
2976 	proto_unregister(&smc_proto);
2977 	smc_pnet_exit();
2978 	smc_nl_exit();
2979 	smc_clc_exit();
2980 	unregister_pernet_subsys(&smc_net_stat_ops);
2981 	unregister_pernet_subsys(&smc_net_ops);
2982 	rcu_barrier();
2983 }
2984 
2985 module_init(smc_init);
2986 module_exit(smc_exit);
2987 
2988 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
2989 MODULE_DESCRIPTION("smc socket address family");
2990 MODULE_LICENSE("GPL");
2991 MODULE_ALIAS_NETPROTO(PF_SMC);
2992 MODULE_ALIAS_TCP_ULP("smc");
2993