xref: /kernel/linux/linux-6.6/net/smc/af_smc.c (revision 62306a36)
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
57static DEFINE_MUTEX(smc_server_lgr_pending);	/* serialize link group
58						 * creation on server
59						 */
60static DEFINE_MUTEX(smc_client_lgr_pending);	/* serialize link group
61						 * creation on client
62						 */
63
64static struct workqueue_struct	*smc_tcp_ls_wq;	/* wq for tcp listen work */
65struct workqueue_struct	*smc_hs_wq;	/* wq for handshake work */
66struct workqueue_struct	*smc_close_wq;	/* wq for close work */
67
68static void smc_tcp_listen_work(struct work_struct *);
69static void smc_connect_work(struct work_struct *);
70
71int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb)
72{
73	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
74	void *hdr;
75
76	if (cb_ctx->pos[0])
77		goto out;
78
79	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
80			  &smc_gen_nl_family, NLM_F_MULTI,
81			  SMC_NETLINK_DUMP_HS_LIMITATION);
82	if (!hdr)
83		return -ENOMEM;
84
85	if (nla_put_u8(skb, SMC_NLA_HS_LIMITATION_ENABLED,
86		       sock_net(skb->sk)->smc.limit_smc_hs))
87		goto err;
88
89	genlmsg_end(skb, hdr);
90	cb_ctx->pos[0] = 1;
91out:
92	return skb->len;
93err:
94	genlmsg_cancel(skb, hdr);
95	return -EMSGSIZE;
96}
97
98int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
99{
100	sock_net(skb->sk)->smc.limit_smc_hs = true;
101	return 0;
102}
103
104int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info)
105{
106	sock_net(skb->sk)->smc.limit_smc_hs = false;
107	return 0;
108}
109
110static void smc_set_keepalive(struct sock *sk, int val)
111{
112	struct smc_sock *smc = smc_sk(sk);
113
114	smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
115}
116
117static struct sock *smc_tcp_syn_recv_sock(const struct sock *sk,
118					  struct sk_buff *skb,
119					  struct request_sock *req,
120					  struct dst_entry *dst,
121					  struct request_sock *req_unhash,
122					  bool *own_req)
123{
124	struct smc_sock *smc;
125	struct sock *child;
126
127	smc = smc_clcsock_user_data(sk);
128
129	if (READ_ONCE(sk->sk_ack_backlog) + atomic_read(&smc->queued_smc_hs) >
130				sk->sk_max_ack_backlog)
131		goto drop;
132
133	if (sk_acceptq_is_full(&smc->sk)) {
134		NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
135		goto drop;
136	}
137
138	/* passthrough to original syn recv sock fct */
139	child = smc->ori_af_ops->syn_recv_sock(sk, skb, req, dst, req_unhash,
140					       own_req);
141	/* child must not inherit smc or its ops */
142	if (child) {
143		rcu_assign_sk_user_data(child, NULL);
144
145		/* v4-mapped sockets don't inherit parent ops. Don't restore. */
146		if (inet_csk(child)->icsk_af_ops == inet_csk(sk)->icsk_af_ops)
147			inet_csk(child)->icsk_af_ops = smc->ori_af_ops;
148	}
149	return child;
150
151drop:
152	dst_release(dst);
153	tcp_listendrop(sk);
154	return NULL;
155}
156
157static bool smc_hs_congested(const struct sock *sk)
158{
159	const struct smc_sock *smc;
160
161	smc = smc_clcsock_user_data(sk);
162
163	if (!smc)
164		return true;
165
166	if (workqueue_congested(WORK_CPU_UNBOUND, smc_hs_wq))
167		return true;
168
169	return false;
170}
171
172static struct smc_hashinfo smc_v4_hashinfo = {
173	.lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
174};
175
176static struct smc_hashinfo smc_v6_hashinfo = {
177	.lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
178};
179
180int smc_hash_sk(struct sock *sk)
181{
182	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
183	struct hlist_head *head;
184
185	head = &h->ht;
186
187	write_lock_bh(&h->lock);
188	sk_add_node(sk, head);
189	write_unlock_bh(&h->lock);
190	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
191
192	return 0;
193}
194EXPORT_SYMBOL_GPL(smc_hash_sk);
195
196void smc_unhash_sk(struct sock *sk)
197{
198	struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
199
200	write_lock_bh(&h->lock);
201	if (sk_del_node_init(sk))
202		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
203	write_unlock_bh(&h->lock);
204}
205EXPORT_SYMBOL_GPL(smc_unhash_sk);
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 */
211static 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
221struct 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};
232EXPORT_SYMBOL_GPL(smc_proto);
233
234struct 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};
245EXPORT_SYMBOL_GPL(smc_proto6);
246
247static 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
262static 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
271static 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
311static 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 */
353out:
354	return rc;
355}
356
357static 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
365static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
366				   int protocol)
367{
368	struct smc_sock *smc;
369	struct proto *prot;
370	struct sock *sk;
371
372	prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
373	sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
374	if (!sk)
375		return NULL;
376
377	sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
378	sk->sk_state = SMC_INIT;
379	sk->sk_destruct = smc_destruct;
380	sk->sk_protocol = protocol;
381	WRITE_ONCE(sk->sk_sndbuf, 2 * READ_ONCE(net->smc.sysctl_wmem));
382	WRITE_ONCE(sk->sk_rcvbuf, 2 * READ_ONCE(net->smc.sysctl_rmem));
383	smc = smc_sk(sk);
384	INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
385	INIT_WORK(&smc->connect_work, smc_connect_work);
386	INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
387	INIT_LIST_HEAD(&smc->accept_q);
388	spin_lock_init(&smc->accept_q_lock);
389	spin_lock_init(&smc->conn.send_lock);
390	sk->sk_prot->hash(sk);
391	mutex_init(&smc->clcsock_release_lock);
392	smc_init_saved_callbacks(smc);
393
394	return sk;
395}
396
397static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
398		    int addr_len)
399{
400	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
401	struct sock *sk = sock->sk;
402	struct smc_sock *smc;
403	int rc;
404
405	smc = smc_sk(sk);
406
407	/* replicate tests from inet_bind(), to be safe wrt. future changes */
408	rc = -EINVAL;
409	if (addr_len < sizeof(struct sockaddr_in))
410		goto out;
411
412	rc = -EAFNOSUPPORT;
413	if (addr->sin_family != AF_INET &&
414	    addr->sin_family != AF_INET6 &&
415	    addr->sin_family != AF_UNSPEC)
416		goto out;
417	/* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
418	if (addr->sin_family == AF_UNSPEC &&
419	    addr->sin_addr.s_addr != htonl(INADDR_ANY))
420		goto out;
421
422	lock_sock(sk);
423
424	/* Check if socket is already active */
425	rc = -EINVAL;
426	if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
427		goto out_rel;
428
429	smc->clcsock->sk->sk_reuse = sk->sk_reuse;
430	smc->clcsock->sk->sk_reuseport = sk->sk_reuseport;
431	rc = kernel_bind(smc->clcsock, uaddr, addr_len);
432
433out_rel:
434	release_sock(sk);
435out:
436	return rc;
437}
438
439/* copy only relevant settings and flags of SOL_SOCKET level from smc to
440 * clc socket (since smc is not called for these options from net/core)
441 */
442
443#define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
444			     (1UL << SOCK_KEEPOPEN) | \
445			     (1UL << SOCK_LINGER) | \
446			     (1UL << SOCK_BROADCAST) | \
447			     (1UL << SOCK_TIMESTAMP) | \
448			     (1UL << SOCK_DBG) | \
449			     (1UL << SOCK_RCVTSTAMP) | \
450			     (1UL << SOCK_RCVTSTAMPNS) | \
451			     (1UL << SOCK_LOCALROUTE) | \
452			     (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
453			     (1UL << SOCK_RXQ_OVFL) | \
454			     (1UL << SOCK_WIFI_STATUS) | \
455			     (1UL << SOCK_NOFCS) | \
456			     (1UL << SOCK_FILTER_LOCKED) | \
457			     (1UL << SOCK_TSTAMP_NEW))
458
459/* if set, use value set by setsockopt() - else use IPv4 or SMC sysctl value */
460static void smc_adjust_sock_bufsizes(struct sock *nsk, struct sock *osk,
461				     unsigned long mask)
462{
463	struct net *nnet = sock_net(nsk);
464
465	nsk->sk_userlocks = osk->sk_userlocks;
466	if (osk->sk_userlocks & SOCK_SNDBUF_LOCK) {
467		nsk->sk_sndbuf = osk->sk_sndbuf;
468	} else {
469		if (mask == SK_FLAGS_SMC_TO_CLC)
470			WRITE_ONCE(nsk->sk_sndbuf,
471				   READ_ONCE(nnet->ipv4.sysctl_tcp_wmem[1]));
472		else
473			WRITE_ONCE(nsk->sk_sndbuf,
474				   2 * READ_ONCE(nnet->smc.sysctl_wmem));
475	}
476	if (osk->sk_userlocks & SOCK_RCVBUF_LOCK) {
477		nsk->sk_rcvbuf = osk->sk_rcvbuf;
478	} else {
479		if (mask == SK_FLAGS_SMC_TO_CLC)
480			WRITE_ONCE(nsk->sk_rcvbuf,
481				   READ_ONCE(nnet->ipv4.sysctl_tcp_rmem[1]));
482		else
483			WRITE_ONCE(nsk->sk_rcvbuf,
484				   2 * READ_ONCE(nnet->smc.sysctl_rmem));
485	}
486}
487
488static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
489				   unsigned long mask)
490{
491	/* options we don't get control via setsockopt for */
492	nsk->sk_type = osk->sk_type;
493	nsk->sk_sndtimeo = osk->sk_sndtimeo;
494	nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
495	nsk->sk_mark = READ_ONCE(osk->sk_mark);
496	nsk->sk_priority = osk->sk_priority;
497	nsk->sk_rcvlowat = osk->sk_rcvlowat;
498	nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
499	nsk->sk_err = osk->sk_err;
500
501	nsk->sk_flags &= ~mask;
502	nsk->sk_flags |= osk->sk_flags & mask;
503
504	smc_adjust_sock_bufsizes(nsk, osk, mask);
505}
506
507static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
508{
509	smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
510}
511
512#define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
513			     (1UL << SOCK_KEEPOPEN) | \
514			     (1UL << SOCK_LINGER) | \
515			     (1UL << SOCK_DBG))
516/* copy only settings and flags relevant for smc from clc to smc socket */
517static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
518{
519	smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
520}
521
522/* register the new vzalloced sndbuf on all links */
523static int smcr_lgr_reg_sndbufs(struct smc_link *link,
524				struct smc_buf_desc *snd_desc)
525{
526	struct smc_link_group *lgr = link->lgr;
527	int i, rc = 0;
528
529	if (!snd_desc->is_vm)
530		return -EINVAL;
531
532	/* protect against parallel smcr_link_reg_buf() */
533	down_write(&lgr->llc_conf_mutex);
534	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
535		if (!smc_link_active(&lgr->lnk[i]))
536			continue;
537		rc = smcr_link_reg_buf(&lgr->lnk[i], snd_desc);
538		if (rc)
539			break;
540	}
541	up_write(&lgr->llc_conf_mutex);
542	return rc;
543}
544
545/* register the new rmb on all links */
546static int smcr_lgr_reg_rmbs(struct smc_link *link,
547			     struct smc_buf_desc *rmb_desc)
548{
549	struct smc_link_group *lgr = link->lgr;
550	bool do_slow = false;
551	int i, rc = 0;
552
553	rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
554	if (rc)
555		return rc;
556
557	down_read(&lgr->llc_conf_mutex);
558	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
559		if (!smc_link_active(&lgr->lnk[i]))
560			continue;
561		if (!rmb_desc->is_reg_mr[link->link_idx]) {
562			up_read(&lgr->llc_conf_mutex);
563			goto slow_path;
564		}
565	}
566	/* mr register already */
567	goto fast_path;
568slow_path:
569	do_slow = true;
570	/* protect against parallel smc_llc_cli_rkey_exchange() and
571	 * parallel smcr_link_reg_buf()
572	 */
573	down_write(&lgr->llc_conf_mutex);
574	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
575		if (!smc_link_active(&lgr->lnk[i]))
576			continue;
577		rc = smcr_link_reg_buf(&lgr->lnk[i], rmb_desc);
578		if (rc)
579			goto out;
580	}
581fast_path:
582	/* exchange confirm_rkey msg with peer */
583	rc = smc_llc_do_confirm_rkey(link, rmb_desc);
584	if (rc) {
585		rc = -EFAULT;
586		goto out;
587	}
588	rmb_desc->is_conf_rkey = true;
589out:
590	do_slow ? up_write(&lgr->llc_conf_mutex) : up_read(&lgr->llc_conf_mutex);
591	smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
592	return rc;
593}
594
595static int smcr_clnt_conf_first_link(struct smc_sock *smc)
596{
597	struct smc_link *link = smc->conn.lnk;
598	struct smc_llc_qentry *qentry;
599	int rc;
600
601	/* Receive CONFIRM LINK request from server over RoCE fabric.
602	 * Increasing the client's timeout by twice as much as the server's
603	 * timeout by default can temporarily avoid decline messages of
604	 * both sides crossing or colliding
605	 */
606	qentry = smc_llc_wait(link->lgr, NULL, 2 * SMC_LLC_WAIT_TIME,
607			      SMC_LLC_CONFIRM_LINK);
608	if (!qentry) {
609		struct smc_clc_msg_decline dclc;
610
611		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
612				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
613		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
614	}
615	smc_llc_save_peer_uid(qentry);
616	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_REQ);
617	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
618	if (rc)
619		return SMC_CLC_DECL_RMBE_EC;
620
621	rc = smc_ib_modify_qp_rts(link);
622	if (rc)
623		return SMC_CLC_DECL_ERR_RDYLNK;
624
625	smc_wr_remember_qp_attr(link);
626
627	/* reg the sndbuf if it was vzalloced */
628	if (smc->conn.sndbuf_desc->is_vm) {
629		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
630			return SMC_CLC_DECL_ERR_REGBUF;
631	}
632
633	/* reg the rmb */
634	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
635		return SMC_CLC_DECL_ERR_REGBUF;
636
637	/* confirm_rkey is implicit on 1st contact */
638	smc->conn.rmb_desc->is_conf_rkey = true;
639
640	/* send CONFIRM LINK response over RoCE fabric */
641	rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
642	if (rc < 0)
643		return SMC_CLC_DECL_TIMEOUT_CL;
644
645	smc_llc_link_active(link);
646	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
647
648	if (link->lgr->max_links > 1) {
649		/* optional 2nd link, receive ADD LINK request from server */
650		qentry = smc_llc_wait(link->lgr, NULL, SMC_LLC_WAIT_TIME,
651				      SMC_LLC_ADD_LINK);
652		if (!qentry) {
653			struct smc_clc_msg_decline dclc;
654
655			rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
656					      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
657			if (rc == -EAGAIN)
658				rc = 0; /* no DECLINE received, go with one link */
659			return rc;
660		}
661		smc_llc_flow_qentry_clr(&link->lgr->llc_flow_lcl);
662		smc_llc_cli_add_link(link, qentry);
663	}
664	return 0;
665}
666
667static bool smc_isascii(char *hostname)
668{
669	int i;
670
671	for (i = 0; i < SMC_MAX_HOSTNAME_LEN; i++)
672		if (!isascii(hostname[i]))
673			return false;
674	return true;
675}
676
677static void smc_conn_save_peer_info_fce(struct smc_sock *smc,
678					struct smc_clc_msg_accept_confirm *clc)
679{
680	struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
681		(struct smc_clc_msg_accept_confirm_v2 *)clc;
682	struct smc_clc_first_contact_ext *fce;
683	int clc_v2_len;
684
685	if (clc->hdr.version == SMC_V1 ||
686	    !(clc->hdr.typev2 & SMC_FIRST_CONTACT_MASK))
687		return;
688
689	if (smc->conn.lgr->is_smcd) {
690		memcpy(smc->conn.lgr->negotiated_eid, clc_v2->d1.eid,
691		       SMC_MAX_EID_LEN);
692		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
693					 d1);
694	} else {
695		memcpy(smc->conn.lgr->negotiated_eid, clc_v2->r1.eid,
696		       SMC_MAX_EID_LEN);
697		clc_v2_len = offsetofend(struct smc_clc_msg_accept_confirm_v2,
698					 r1);
699	}
700	fce = (struct smc_clc_first_contact_ext *)(((u8 *)clc_v2) + clc_v2_len);
701	smc->conn.lgr->peer_os = fce->os_type;
702	smc->conn.lgr->peer_smc_release = fce->release;
703	if (smc_isascii(fce->hostname))
704		memcpy(smc->conn.lgr->peer_hostname, fce->hostname,
705		       SMC_MAX_HOSTNAME_LEN);
706}
707
708static void smcr_conn_save_peer_info(struct smc_sock *smc,
709				     struct smc_clc_msg_accept_confirm *clc)
710{
711	int bufsize = smc_uncompress_bufsize(clc->r0.rmbe_size);
712
713	smc->conn.peer_rmbe_idx = clc->r0.rmbe_idx;
714	smc->conn.local_tx_ctrl.token = ntohl(clc->r0.rmbe_alert_token);
715	smc->conn.peer_rmbe_size = bufsize;
716	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
717	smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
718}
719
720static void smcd_conn_save_peer_info(struct smc_sock *smc,
721				     struct smc_clc_msg_accept_confirm *clc)
722{
723	int bufsize = smc_uncompress_bufsize(clc->d0.dmbe_size);
724
725	smc->conn.peer_rmbe_idx = clc->d0.dmbe_idx;
726	smc->conn.peer_token = ntohll(clc->d0.token);
727	/* msg header takes up space in the buffer */
728	smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
729	atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
730	smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
731}
732
733static void smc_conn_save_peer_info(struct smc_sock *smc,
734				    struct smc_clc_msg_accept_confirm *clc)
735{
736	if (smc->conn.lgr->is_smcd)
737		smcd_conn_save_peer_info(smc, clc);
738	else
739		smcr_conn_save_peer_info(smc, clc);
740	smc_conn_save_peer_info_fce(smc, clc);
741}
742
743static void smc_link_save_peer_info(struct smc_link *link,
744				    struct smc_clc_msg_accept_confirm *clc,
745				    struct smc_init_info *ini)
746{
747	link->peer_qpn = ntoh24(clc->r0.qpn);
748	memcpy(link->peer_gid, ini->peer_gid, SMC_GID_SIZE);
749	memcpy(link->peer_mac, ini->peer_mac, sizeof(link->peer_mac));
750	link->peer_psn = ntoh24(clc->r0.psn);
751	link->peer_mtu = clc->r0.qp_mtu;
752}
753
754static void smc_stat_inc_fback_rsn_cnt(struct smc_sock *smc,
755				       struct smc_stats_fback *fback_arr)
756{
757	int cnt;
758
759	for (cnt = 0; cnt < SMC_MAX_FBACK_RSN_CNT; cnt++) {
760		if (fback_arr[cnt].fback_code == smc->fallback_rsn) {
761			fback_arr[cnt].count++;
762			break;
763		}
764		if (!fback_arr[cnt].fback_code) {
765			fback_arr[cnt].fback_code = smc->fallback_rsn;
766			fback_arr[cnt].count++;
767			break;
768		}
769	}
770}
771
772static void smc_stat_fallback(struct smc_sock *smc)
773{
774	struct net *net = sock_net(&smc->sk);
775
776	mutex_lock(&net->smc.mutex_fback_rsn);
777	if (smc->listen_smc) {
778		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->srv);
779		net->smc.fback_rsn->srv_fback_cnt++;
780	} else {
781		smc_stat_inc_fback_rsn_cnt(smc, net->smc.fback_rsn->clnt);
782		net->smc.fback_rsn->clnt_fback_cnt++;
783	}
784	mutex_unlock(&net->smc.mutex_fback_rsn);
785}
786
787/* must be called under rcu read lock */
788static void smc_fback_wakeup_waitqueue(struct smc_sock *smc, void *key)
789{
790	struct socket_wq *wq;
791	__poll_t flags;
792
793	wq = rcu_dereference(smc->sk.sk_wq);
794	if (!skwq_has_sleeper(wq))
795		return;
796
797	/* wake up smc sk->sk_wq */
798	if (!key) {
799		/* sk_state_change */
800		wake_up_interruptible_all(&wq->wait);
801	} else {
802		flags = key_to_poll(key);
803		if (flags & (EPOLLIN | EPOLLOUT))
804			/* sk_data_ready or sk_write_space */
805			wake_up_interruptible_sync_poll(&wq->wait, flags);
806		else if (flags & EPOLLERR)
807			/* sk_error_report */
808			wake_up_interruptible_poll(&wq->wait, flags);
809	}
810}
811
812static int smc_fback_mark_woken(wait_queue_entry_t *wait,
813				unsigned int mode, int sync, void *key)
814{
815	struct smc_mark_woken *mark =
816		container_of(wait, struct smc_mark_woken, wait_entry);
817
818	mark->woken = true;
819	mark->key = key;
820	return 0;
821}
822
823static void smc_fback_forward_wakeup(struct smc_sock *smc, struct sock *clcsk,
824				     void (*clcsock_callback)(struct sock *sk))
825{
826	struct smc_mark_woken mark = { .woken = false };
827	struct socket_wq *wq;
828
829	init_waitqueue_func_entry(&mark.wait_entry,
830				  smc_fback_mark_woken);
831	rcu_read_lock();
832	wq = rcu_dereference(clcsk->sk_wq);
833	if (!wq)
834		goto out;
835	add_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
836	clcsock_callback(clcsk);
837	remove_wait_queue(sk_sleep(clcsk), &mark.wait_entry);
838
839	if (mark.woken)
840		smc_fback_wakeup_waitqueue(smc, mark.key);
841out:
842	rcu_read_unlock();
843}
844
845static void smc_fback_state_change(struct sock *clcsk)
846{
847	struct smc_sock *smc;
848
849	read_lock_bh(&clcsk->sk_callback_lock);
850	smc = smc_clcsock_user_data(clcsk);
851	if (smc)
852		smc_fback_forward_wakeup(smc, clcsk,
853					 smc->clcsk_state_change);
854	read_unlock_bh(&clcsk->sk_callback_lock);
855}
856
857static void smc_fback_data_ready(struct sock *clcsk)
858{
859	struct smc_sock *smc;
860
861	read_lock_bh(&clcsk->sk_callback_lock);
862	smc = smc_clcsock_user_data(clcsk);
863	if (smc)
864		smc_fback_forward_wakeup(smc, clcsk,
865					 smc->clcsk_data_ready);
866	read_unlock_bh(&clcsk->sk_callback_lock);
867}
868
869static void smc_fback_write_space(struct sock *clcsk)
870{
871	struct smc_sock *smc;
872
873	read_lock_bh(&clcsk->sk_callback_lock);
874	smc = smc_clcsock_user_data(clcsk);
875	if (smc)
876		smc_fback_forward_wakeup(smc, clcsk,
877					 smc->clcsk_write_space);
878	read_unlock_bh(&clcsk->sk_callback_lock);
879}
880
881static void smc_fback_error_report(struct sock *clcsk)
882{
883	struct smc_sock *smc;
884
885	read_lock_bh(&clcsk->sk_callback_lock);
886	smc = smc_clcsock_user_data(clcsk);
887	if (smc)
888		smc_fback_forward_wakeup(smc, clcsk,
889					 smc->clcsk_error_report);
890	read_unlock_bh(&clcsk->sk_callback_lock);
891}
892
893static void smc_fback_replace_callbacks(struct smc_sock *smc)
894{
895	struct sock *clcsk = smc->clcsock->sk;
896
897	write_lock_bh(&clcsk->sk_callback_lock);
898	clcsk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
899
900	smc_clcsock_replace_cb(&clcsk->sk_state_change, smc_fback_state_change,
901			       &smc->clcsk_state_change);
902	smc_clcsock_replace_cb(&clcsk->sk_data_ready, smc_fback_data_ready,
903			       &smc->clcsk_data_ready);
904	smc_clcsock_replace_cb(&clcsk->sk_write_space, smc_fback_write_space,
905			       &smc->clcsk_write_space);
906	smc_clcsock_replace_cb(&clcsk->sk_error_report, smc_fback_error_report,
907			       &smc->clcsk_error_report);
908
909	write_unlock_bh(&clcsk->sk_callback_lock);
910}
911
912static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code)
913{
914	int rc = 0;
915
916	mutex_lock(&smc->clcsock_release_lock);
917	if (!smc->clcsock) {
918		rc = -EBADF;
919		goto out;
920	}
921
922	smc->use_fallback = true;
923	smc->fallback_rsn = reason_code;
924	smc_stat_fallback(smc);
925	trace_smc_switch_to_fallback(smc, reason_code);
926	if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
927		smc->clcsock->file = smc->sk.sk_socket->file;
928		smc->clcsock->file->private_data = smc->clcsock;
929		smc->clcsock->wq.fasync_list =
930			smc->sk.sk_socket->wq.fasync_list;
931
932		/* There might be some wait entries remaining
933		 * in smc sk->sk_wq and they should be woken up
934		 * as clcsock's wait queue is woken up.
935		 */
936		smc_fback_replace_callbacks(smc);
937	}
938out:
939	mutex_unlock(&smc->clcsock_release_lock);
940	return rc;
941}
942
943/* fall back during connect */
944static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
945{
946	struct net *net = sock_net(&smc->sk);
947	int rc = 0;
948
949	rc = smc_switch_to_fallback(smc, reason_code);
950	if (rc) { /* fallback fails */
951		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
952		if (smc->sk.sk_state == SMC_INIT)
953			sock_put(&smc->sk); /* passive closing */
954		return rc;
955	}
956	smc_copy_sock_settings_to_clc(smc);
957	smc->connect_nonblock = 0;
958	if (smc->sk.sk_state == SMC_INIT)
959		smc->sk.sk_state = SMC_ACTIVE;
960	return 0;
961}
962
963/* decline and fall back during connect */
964static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code,
965					u8 version)
966{
967	struct net *net = sock_net(&smc->sk);
968	int rc;
969
970	if (reason_code < 0) { /* error, fallback is not possible */
971		this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
972		if (smc->sk.sk_state == SMC_INIT)
973			sock_put(&smc->sk); /* passive closing */
974		return reason_code;
975	}
976	if (reason_code != SMC_CLC_DECL_PEERDECL) {
977		rc = smc_clc_send_decline(smc, reason_code, version);
978		if (rc < 0) {
979			this_cpu_inc(net->smc.smc_stats->clnt_hshake_err_cnt);
980			if (smc->sk.sk_state == SMC_INIT)
981				sock_put(&smc->sk); /* passive closing */
982			return rc;
983		}
984	}
985	return smc_connect_fallback(smc, reason_code);
986}
987
988static void smc_conn_abort(struct smc_sock *smc, int local_first)
989{
990	struct smc_connection *conn = &smc->conn;
991	struct smc_link_group *lgr = conn->lgr;
992	bool lgr_valid = false;
993
994	if (smc_conn_lgr_valid(conn))
995		lgr_valid = true;
996
997	smc_conn_free(conn);
998	if (local_first && lgr_valid)
999		smc_lgr_cleanup_early(lgr);
1000}
1001
1002/* check if there is a rdma device available for this connection. */
1003/* called for connect and listen */
1004static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
1005{
1006	/* PNET table look up: search active ib_device and port
1007	 * within same PNETID that also contains the ethernet device
1008	 * used for the internal TCP socket
1009	 */
1010	smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
1011	if (!ini->check_smcrv2 && !ini->ib_dev)
1012		return SMC_CLC_DECL_NOSMCRDEV;
1013	if (ini->check_smcrv2 && !ini->smcrv2.ib_dev_v2)
1014		return SMC_CLC_DECL_NOSMCRDEV;
1015	return 0;
1016}
1017
1018/* check if there is an ISM device available for this connection. */
1019/* called for connect and listen */
1020static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
1021{
1022	/* Find ISM device with same PNETID as connecting interface  */
1023	smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
1024	if (!ini->ism_dev[0])
1025		return SMC_CLC_DECL_NOSMCDDEV;
1026	else
1027		ini->ism_chid[0] = smc_ism_get_chid(ini->ism_dev[0]);
1028	return 0;
1029}
1030
1031/* is chid unique for the ism devices that are already determined? */
1032static bool smc_find_ism_v2_is_unique_chid(u16 chid, struct smc_init_info *ini,
1033					   int cnt)
1034{
1035	int i = (!ini->ism_dev[0]) ? 1 : 0;
1036
1037	for (; i < cnt; i++)
1038		if (ini->ism_chid[i] == chid)
1039			return false;
1040	return true;
1041}
1042
1043/* determine possible V2 ISM devices (either without PNETID or with PNETID plus
1044 * PNETID matching net_device)
1045 */
1046static int smc_find_ism_v2_device_clnt(struct smc_sock *smc,
1047				       struct smc_init_info *ini)
1048{
1049	int rc = SMC_CLC_DECL_NOSMCDDEV;
1050	struct smcd_dev *smcd;
1051	int i = 1;
1052	u16 chid;
1053
1054	if (smcd_indicated(ini->smc_type_v1))
1055		rc = 0;		/* already initialized for V1 */
1056	mutex_lock(&smcd_dev_list.mutex);
1057	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1058		if (smcd->going_away || smcd == ini->ism_dev[0])
1059			continue;
1060		chid = smc_ism_get_chid(smcd);
1061		if (!smc_find_ism_v2_is_unique_chid(chid, ini, i))
1062			continue;
1063		if (!smc_pnet_is_pnetid_set(smcd->pnetid) ||
1064		    smc_pnet_is_ndev_pnetid(sock_net(&smc->sk), smcd->pnetid)) {
1065			ini->ism_dev[i] = smcd;
1066			ini->ism_chid[i] = chid;
1067			ini->is_smcd = true;
1068			rc = 0;
1069			i++;
1070			if (i > SMC_MAX_ISM_DEVS)
1071				break;
1072		}
1073	}
1074	mutex_unlock(&smcd_dev_list.mutex);
1075	ini->ism_offered_cnt = i - 1;
1076	if (!ini->ism_dev[0] && !ini->ism_dev[1])
1077		ini->smcd_version = 0;
1078
1079	return rc;
1080}
1081
1082/* Check for VLAN ID and register it on ISM device just for CLC handshake */
1083static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
1084				      struct smc_init_info *ini)
1085{
1086	if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev[0], ini->vlan_id))
1087		return SMC_CLC_DECL_ISMVLANERR;
1088	return 0;
1089}
1090
1091static int smc_find_proposal_devices(struct smc_sock *smc,
1092				     struct smc_init_info *ini)
1093{
1094	int rc = 0;
1095
1096	/* check if there is an ism device available */
1097	if (!(ini->smcd_version & SMC_V1) ||
1098	    smc_find_ism_device(smc, ini) ||
1099	    smc_connect_ism_vlan_setup(smc, ini))
1100		ini->smcd_version &= ~SMC_V1;
1101	/* else ISM V1 is supported for this connection */
1102
1103	/* check if there is an rdma device available */
1104	if (!(ini->smcr_version & SMC_V1) ||
1105	    smc_find_rdma_device(smc, ini))
1106		ini->smcr_version &= ~SMC_V1;
1107	/* else RDMA is supported for this connection */
1108
1109	ini->smc_type_v1 = smc_indicated_type(ini->smcd_version & SMC_V1,
1110					      ini->smcr_version & SMC_V1);
1111
1112	/* check if there is an ism v2 device available */
1113	if (!(ini->smcd_version & SMC_V2) ||
1114	    !smc_ism_is_v2_capable() ||
1115	    smc_find_ism_v2_device_clnt(smc, ini))
1116		ini->smcd_version &= ~SMC_V2;
1117
1118	/* check if there is an rdma v2 device available */
1119	ini->check_smcrv2 = true;
1120	ini->smcrv2.saddr = smc->clcsock->sk->sk_rcv_saddr;
1121	if (!(ini->smcr_version & SMC_V2) ||
1122	    smc->clcsock->sk->sk_family != AF_INET ||
1123	    !smc_clc_ueid_count() ||
1124	    smc_find_rdma_device(smc, ini))
1125		ini->smcr_version &= ~SMC_V2;
1126	ini->check_smcrv2 = false;
1127
1128	ini->smc_type_v2 = smc_indicated_type(ini->smcd_version & SMC_V2,
1129					      ini->smcr_version & SMC_V2);
1130
1131	/* if neither ISM nor RDMA are supported, fallback */
1132	if (ini->smc_type_v1 == SMC_TYPE_N && ini->smc_type_v2 == SMC_TYPE_N)
1133		rc = SMC_CLC_DECL_NOSMCDEV;
1134
1135	return rc;
1136}
1137
1138/* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
1139 * used, the VLAN ID will be registered again during the connection setup.
1140 */
1141static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc,
1142					struct smc_init_info *ini)
1143{
1144	if (!smcd_indicated(ini->smc_type_v1))
1145		return 0;
1146	if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev[0], ini->vlan_id))
1147		return SMC_CLC_DECL_CNFERR;
1148	return 0;
1149}
1150
1151#define SMC_CLC_MAX_ACCEPT_LEN \
1152	(sizeof(struct smc_clc_msg_accept_confirm_v2) + \
1153	 sizeof(struct smc_clc_first_contact_ext_v2x) + \
1154	 sizeof(struct smc_clc_msg_trail))
1155
1156/* CLC handshake during connect */
1157static int smc_connect_clc(struct smc_sock *smc,
1158			   struct smc_clc_msg_accept_confirm_v2 *aclc2,
1159			   struct smc_init_info *ini)
1160{
1161	int rc = 0;
1162
1163	/* do inband token exchange */
1164	rc = smc_clc_send_proposal(smc, ini);
1165	if (rc)
1166		return rc;
1167	/* receive SMC Accept CLC message */
1168	return smc_clc_wait_msg(smc, aclc2, SMC_CLC_MAX_ACCEPT_LEN,
1169				SMC_CLC_ACCEPT, CLC_WAIT_TIME);
1170}
1171
1172void smc_fill_gid_list(struct smc_link_group *lgr,
1173		       struct smc_gidlist *gidlist,
1174		       struct smc_ib_device *known_dev, u8 *known_gid)
1175{
1176	struct smc_init_info *alt_ini = NULL;
1177
1178	memset(gidlist, 0, sizeof(*gidlist));
1179	memcpy(gidlist->list[gidlist->len++], known_gid, SMC_GID_SIZE);
1180
1181	alt_ini = kzalloc(sizeof(*alt_ini), GFP_KERNEL);
1182	if (!alt_ini)
1183		goto out;
1184
1185	alt_ini->vlan_id = lgr->vlan_id;
1186	alt_ini->check_smcrv2 = true;
1187	alt_ini->smcrv2.saddr = lgr->saddr;
1188	smc_pnet_find_alt_roce(lgr, alt_ini, known_dev);
1189
1190	if (!alt_ini->smcrv2.ib_dev_v2)
1191		goto out;
1192
1193	memcpy(gidlist->list[gidlist->len++], alt_ini->smcrv2.ib_gid_v2,
1194	       SMC_GID_SIZE);
1195
1196out:
1197	kfree(alt_ini);
1198}
1199
1200static int smc_connect_rdma_v2_prepare(struct smc_sock *smc,
1201				       struct smc_clc_msg_accept_confirm *aclc,
1202				       struct smc_init_info *ini)
1203{
1204	struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1205		(struct smc_clc_msg_accept_confirm_v2 *)aclc;
1206	struct smc_clc_first_contact_ext *fce =
1207		smc_get_clc_first_contact_ext(clc_v2, false);
1208	struct net *net = sock_net(&smc->sk);
1209	int rc;
1210
1211	if (!ini->first_contact_peer || aclc->hdr.version == SMC_V1)
1212		return 0;
1213
1214	if (fce->v2_direct) {
1215		memcpy(ini->smcrv2.nexthop_mac, &aclc->r0.lcl.mac, ETH_ALEN);
1216		ini->smcrv2.uses_gateway = false;
1217	} else {
1218		if (smc_ib_find_route(net, smc->clcsock->sk->sk_rcv_saddr,
1219				      smc_ib_gid_to_ipv4(aclc->r0.lcl.gid),
1220				      ini->smcrv2.nexthop_mac,
1221				      &ini->smcrv2.uses_gateway))
1222			return SMC_CLC_DECL_NOROUTE;
1223		if (!ini->smcrv2.uses_gateway) {
1224			/* mismatch: peer claims indirect, but its direct */
1225			return SMC_CLC_DECL_NOINDIRECT;
1226		}
1227	}
1228
1229	ini->release_nr = fce->release;
1230	rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1231	if (rc)
1232		return rc;
1233
1234	return 0;
1235}
1236
1237/* setup for RDMA connection of client */
1238static int smc_connect_rdma(struct smc_sock *smc,
1239			    struct smc_clc_msg_accept_confirm *aclc,
1240			    struct smc_init_info *ini)
1241{
1242	int i, reason_code = 0;
1243	struct smc_link *link;
1244	u8 *eid = NULL;
1245
1246	ini->is_smcd = false;
1247	ini->ib_clcqpn = ntoh24(aclc->r0.qpn);
1248	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1249	memcpy(ini->peer_systemid, aclc->r0.lcl.id_for_peer, SMC_SYSTEMID_LEN);
1250	memcpy(ini->peer_gid, aclc->r0.lcl.gid, SMC_GID_SIZE);
1251	memcpy(ini->peer_mac, aclc->r0.lcl.mac, ETH_ALEN);
1252	ini->max_conns = SMC_CONN_PER_LGR_MAX;
1253	ini->max_links = SMC_LINKS_ADD_LNK_MAX;
1254
1255	reason_code = smc_connect_rdma_v2_prepare(smc, aclc, ini);
1256	if (reason_code)
1257		return reason_code;
1258
1259	mutex_lock(&smc_client_lgr_pending);
1260	reason_code = smc_conn_create(smc, ini);
1261	if (reason_code) {
1262		mutex_unlock(&smc_client_lgr_pending);
1263		return reason_code;
1264	}
1265
1266	smc_conn_save_peer_info(smc, aclc);
1267
1268	if (ini->first_contact_local) {
1269		link = smc->conn.lnk;
1270	} else {
1271		/* set link that was assigned by server */
1272		link = NULL;
1273		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1274			struct smc_link *l = &smc->conn.lgr->lnk[i];
1275
1276			if (l->peer_qpn == ntoh24(aclc->r0.qpn) &&
1277			    !memcmp(l->peer_gid, &aclc->r0.lcl.gid,
1278				    SMC_GID_SIZE) &&
1279			    (aclc->hdr.version > SMC_V1 ||
1280			     !memcmp(l->peer_mac, &aclc->r0.lcl.mac,
1281				     sizeof(l->peer_mac)))) {
1282				link = l;
1283				break;
1284			}
1285		}
1286		if (!link) {
1287			reason_code = SMC_CLC_DECL_NOSRVLINK;
1288			goto connect_abort;
1289		}
1290		smc_switch_link_and_count(&smc->conn, link);
1291	}
1292
1293	/* create send buffer and rmb */
1294	if (smc_buf_create(smc, false)) {
1295		reason_code = SMC_CLC_DECL_MEM;
1296		goto connect_abort;
1297	}
1298
1299	if (ini->first_contact_local)
1300		smc_link_save_peer_info(link, aclc, ini);
1301
1302	if (smc_rmb_rtoken_handling(&smc->conn, link, aclc)) {
1303		reason_code = SMC_CLC_DECL_ERR_RTOK;
1304		goto connect_abort;
1305	}
1306
1307	smc_close_init(smc);
1308	smc_rx_init(smc);
1309
1310	if (ini->first_contact_local) {
1311		if (smc_ib_ready_link(link)) {
1312			reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1313			goto connect_abort;
1314		}
1315	} else {
1316		/* reg sendbufs if they were vzalloced */
1317		if (smc->conn.sndbuf_desc->is_vm) {
1318			if (smcr_lgr_reg_sndbufs(link, smc->conn.sndbuf_desc)) {
1319				reason_code = SMC_CLC_DECL_ERR_REGBUF;
1320				goto connect_abort;
1321			}
1322		}
1323		if (smcr_lgr_reg_rmbs(link, smc->conn.rmb_desc)) {
1324			reason_code = SMC_CLC_DECL_ERR_REGBUF;
1325			goto connect_abort;
1326		}
1327	}
1328
1329	if (aclc->hdr.version > SMC_V1) {
1330		struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1331			(struct smc_clc_msg_accept_confirm_v2 *)aclc;
1332
1333		eid = clc_v2->r1.eid;
1334		if (ini->first_contact_local)
1335			smc_fill_gid_list(link->lgr, &ini->smcrv2.gidlist,
1336					  link->smcibdev, link->gid);
1337	}
1338
1339	reason_code = smc_clc_send_confirm(smc, ini->first_contact_local,
1340					   aclc->hdr.version, eid, ini);
1341	if (reason_code)
1342		goto connect_abort;
1343
1344	smc_tx_init(smc);
1345
1346	if (ini->first_contact_local) {
1347		/* QP confirmation over RoCE fabric */
1348		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
1349		reason_code = smcr_clnt_conf_first_link(smc);
1350		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
1351		if (reason_code)
1352			goto connect_abort;
1353	}
1354	mutex_unlock(&smc_client_lgr_pending);
1355
1356	smc_copy_sock_settings_to_clc(smc);
1357	smc->connect_nonblock = 0;
1358	if (smc->sk.sk_state == SMC_INIT)
1359		smc->sk.sk_state = SMC_ACTIVE;
1360
1361	return 0;
1362connect_abort:
1363	smc_conn_abort(smc, ini->first_contact_local);
1364	mutex_unlock(&smc_client_lgr_pending);
1365	smc->connect_nonblock = 0;
1366
1367	return reason_code;
1368}
1369
1370/* The server has chosen one of the proposed ISM devices for the communication.
1371 * Determine from the CHID of the received CLC ACCEPT the ISM device chosen.
1372 */
1373static int
1374smc_v2_determine_accepted_chid(struct smc_clc_msg_accept_confirm_v2 *aclc,
1375			       struct smc_init_info *ini)
1376{
1377	int i;
1378
1379	for (i = 0; i < ini->ism_offered_cnt + 1; i++) {
1380		if (ini->ism_chid[i] == ntohs(aclc->d1.chid)) {
1381			ini->ism_selected = i;
1382			return 0;
1383		}
1384	}
1385
1386	return -EPROTO;
1387}
1388
1389/* setup for ISM connection of client */
1390static int smc_connect_ism(struct smc_sock *smc,
1391			   struct smc_clc_msg_accept_confirm *aclc,
1392			   struct smc_init_info *ini)
1393{
1394	u8 *eid = NULL;
1395	int rc = 0;
1396
1397	ini->is_smcd = true;
1398	ini->first_contact_peer = aclc->hdr.typev2 & SMC_FIRST_CONTACT_MASK;
1399
1400	if (aclc->hdr.version == SMC_V2) {
1401		struct smc_clc_msg_accept_confirm_v2 *aclc_v2 =
1402			(struct smc_clc_msg_accept_confirm_v2 *)aclc;
1403
1404		if (ini->first_contact_peer) {
1405			struct smc_clc_first_contact_ext *fce =
1406				smc_get_clc_first_contact_ext(aclc_v2, true);
1407
1408			ini->release_nr = fce->release;
1409			rc = smc_clc_clnt_v2x_features_validate(fce, ini);
1410			if (rc)
1411				return rc;
1412		}
1413
1414		rc = smc_v2_determine_accepted_chid(aclc_v2, ini);
1415		if (rc)
1416			return rc;
1417	}
1418	ini->ism_peer_gid[ini->ism_selected] = ntohll(aclc->d0.gid);
1419
1420	/* there is only one lgr role for SMC-D; use server lock */
1421	mutex_lock(&smc_server_lgr_pending);
1422	rc = smc_conn_create(smc, ini);
1423	if (rc) {
1424		mutex_unlock(&smc_server_lgr_pending);
1425		return rc;
1426	}
1427
1428	/* Create send and receive buffers */
1429	rc = smc_buf_create(smc, true);
1430	if (rc) {
1431		rc = (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB : SMC_CLC_DECL_MEM;
1432		goto connect_abort;
1433	}
1434
1435	smc_conn_save_peer_info(smc, aclc);
1436	smc_close_init(smc);
1437	smc_rx_init(smc);
1438	smc_tx_init(smc);
1439
1440	if (aclc->hdr.version > SMC_V1) {
1441		struct smc_clc_msg_accept_confirm_v2 *clc_v2 =
1442			(struct smc_clc_msg_accept_confirm_v2 *)aclc;
1443
1444		eid = clc_v2->d1.eid;
1445	}
1446
1447	rc = smc_clc_send_confirm(smc, ini->first_contact_local,
1448				  aclc->hdr.version, eid, ini);
1449	if (rc)
1450		goto connect_abort;
1451	mutex_unlock(&smc_server_lgr_pending);
1452
1453	smc_copy_sock_settings_to_clc(smc);
1454	smc->connect_nonblock = 0;
1455	if (smc->sk.sk_state == SMC_INIT)
1456		smc->sk.sk_state = SMC_ACTIVE;
1457
1458	return 0;
1459connect_abort:
1460	smc_conn_abort(smc, ini->first_contact_local);
1461	mutex_unlock(&smc_server_lgr_pending);
1462	smc->connect_nonblock = 0;
1463
1464	return rc;
1465}
1466
1467/* check if received accept type and version matches a proposed one */
1468static int smc_connect_check_aclc(struct smc_init_info *ini,
1469				  struct smc_clc_msg_accept_confirm *aclc)
1470{
1471	if (aclc->hdr.typev1 != SMC_TYPE_R &&
1472	    aclc->hdr.typev1 != SMC_TYPE_D)
1473		return SMC_CLC_DECL_MODEUNSUPP;
1474
1475	if (aclc->hdr.version >= SMC_V2) {
1476		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1477		     !smcr_indicated(ini->smc_type_v2)) ||
1478		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1479		     !smcd_indicated(ini->smc_type_v2)))
1480			return SMC_CLC_DECL_MODEUNSUPP;
1481	} else {
1482		if ((aclc->hdr.typev1 == SMC_TYPE_R &&
1483		     !smcr_indicated(ini->smc_type_v1)) ||
1484		    (aclc->hdr.typev1 == SMC_TYPE_D &&
1485		     !smcd_indicated(ini->smc_type_v1)))
1486			return SMC_CLC_DECL_MODEUNSUPP;
1487	}
1488
1489	return 0;
1490}
1491
1492/* perform steps before actually connecting */
1493static int __smc_connect(struct smc_sock *smc)
1494{
1495	u8 version = smc_ism_is_v2_capable() ? SMC_V2 : SMC_V1;
1496	struct smc_clc_msg_accept_confirm_v2 *aclc2;
1497	struct smc_clc_msg_accept_confirm *aclc;
1498	struct smc_init_info *ini = NULL;
1499	u8 *buf = NULL;
1500	int rc = 0;
1501
1502	if (smc->use_fallback)
1503		return smc_connect_fallback(smc, smc->fallback_rsn);
1504
1505	/* if peer has not signalled SMC-capability, fall back */
1506	if (!tcp_sk(smc->clcsock->sk)->syn_smc)
1507		return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
1508
1509	/* IPSec connections opt out of SMC optimizations */
1510	if (using_ipsec(smc))
1511		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC,
1512						    version);
1513
1514	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1515	if (!ini)
1516		return smc_connect_decline_fallback(smc, SMC_CLC_DECL_MEM,
1517						    version);
1518
1519	ini->smcd_version = SMC_V1 | SMC_V2;
1520	ini->smcr_version = SMC_V1 | SMC_V2;
1521	ini->smc_type_v1 = SMC_TYPE_B;
1522	ini->smc_type_v2 = SMC_TYPE_B;
1523
1524	/* get vlan id from IP device */
1525	if (smc_vlan_by_tcpsk(smc->clcsock, ini)) {
1526		ini->smcd_version &= ~SMC_V1;
1527		ini->smcr_version = 0;
1528		ini->smc_type_v1 = SMC_TYPE_N;
1529		if (!ini->smcd_version) {
1530			rc = SMC_CLC_DECL_GETVLANERR;
1531			goto fallback;
1532		}
1533	}
1534
1535	rc = smc_find_proposal_devices(smc, ini);
1536	if (rc)
1537		goto fallback;
1538
1539	buf = kzalloc(SMC_CLC_MAX_ACCEPT_LEN, GFP_KERNEL);
1540	if (!buf) {
1541		rc = SMC_CLC_DECL_MEM;
1542		goto fallback;
1543	}
1544	aclc2 = (struct smc_clc_msg_accept_confirm_v2 *)buf;
1545	aclc = (struct smc_clc_msg_accept_confirm *)aclc2;
1546
1547	/* perform CLC handshake */
1548	rc = smc_connect_clc(smc, aclc2, ini);
1549	if (rc) {
1550		/* -EAGAIN on timeout, see tcp_recvmsg() */
1551		if (rc == -EAGAIN) {
1552			rc = -ETIMEDOUT;
1553			smc->sk.sk_err = ETIMEDOUT;
1554		}
1555		goto vlan_cleanup;
1556	}
1557
1558	/* check if smc modes and versions of CLC proposal and accept match */
1559	rc = smc_connect_check_aclc(ini, aclc);
1560	version = aclc->hdr.version == SMC_V1 ? SMC_V1 : SMC_V2;
1561	if (rc)
1562		goto vlan_cleanup;
1563
1564	/* depending on previous steps, connect using rdma or ism */
1565	if (aclc->hdr.typev1 == SMC_TYPE_R) {
1566		ini->smcr_version = version;
1567		rc = smc_connect_rdma(smc, aclc, ini);
1568	} else if (aclc->hdr.typev1 == SMC_TYPE_D) {
1569		ini->smcd_version = version;
1570		rc = smc_connect_ism(smc, aclc, ini);
1571	}
1572	if (rc)
1573		goto vlan_cleanup;
1574
1575	SMC_STAT_CLNT_SUCC_INC(sock_net(smc->clcsock->sk), aclc);
1576	smc_connect_ism_vlan_cleanup(smc, ini);
1577	kfree(buf);
1578	kfree(ini);
1579	return 0;
1580
1581vlan_cleanup:
1582	smc_connect_ism_vlan_cleanup(smc, ini);
1583	kfree(buf);
1584fallback:
1585	kfree(ini);
1586	return smc_connect_decline_fallback(smc, rc, version);
1587}
1588
1589static void smc_connect_work(struct work_struct *work)
1590{
1591	struct smc_sock *smc = container_of(work, struct smc_sock,
1592					    connect_work);
1593	long timeo = smc->sk.sk_sndtimeo;
1594	int rc = 0;
1595
1596	if (!timeo)
1597		timeo = MAX_SCHEDULE_TIMEOUT;
1598	lock_sock(smc->clcsock->sk);
1599	if (smc->clcsock->sk->sk_err) {
1600		smc->sk.sk_err = smc->clcsock->sk->sk_err;
1601	} else if ((1 << smc->clcsock->sk->sk_state) &
1602					(TCPF_SYN_SENT | TCPF_SYN_RECV)) {
1603		rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
1604		if ((rc == -EPIPE) &&
1605		    ((1 << smc->clcsock->sk->sk_state) &
1606					(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
1607			rc = 0;
1608	}
1609	release_sock(smc->clcsock->sk);
1610	lock_sock(&smc->sk);
1611	if (rc != 0 || smc->sk.sk_err) {
1612		smc->sk.sk_state = SMC_CLOSED;
1613		if (rc == -EPIPE || rc == -EAGAIN)
1614			smc->sk.sk_err = EPIPE;
1615		else if (rc == -ECONNREFUSED)
1616			smc->sk.sk_err = ECONNREFUSED;
1617		else if (signal_pending(current))
1618			smc->sk.sk_err = -sock_intr_errno(timeo);
1619		sock_put(&smc->sk); /* passive closing */
1620		goto out;
1621	}
1622
1623	rc = __smc_connect(smc);
1624	if (rc < 0)
1625		smc->sk.sk_err = -rc;
1626
1627out:
1628	if (!sock_flag(&smc->sk, SOCK_DEAD)) {
1629		if (smc->sk.sk_err) {
1630			smc->sk.sk_state_change(&smc->sk);
1631		} else { /* allow polling before and after fallback decision */
1632			smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
1633			smc->sk.sk_write_space(&smc->sk);
1634		}
1635	}
1636	release_sock(&smc->sk);
1637}
1638
1639static int smc_connect(struct socket *sock, struct sockaddr *addr,
1640		       int alen, int flags)
1641{
1642	struct sock *sk = sock->sk;
1643	struct smc_sock *smc;
1644	int rc = -EINVAL;
1645
1646	smc = smc_sk(sk);
1647
1648	/* separate smc parameter checking to be safe */
1649	if (alen < sizeof(addr->sa_family))
1650		goto out_err;
1651	if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
1652		goto out_err;
1653
1654	lock_sock(sk);
1655	switch (sock->state) {
1656	default:
1657		rc = -EINVAL;
1658		goto out;
1659	case SS_CONNECTED:
1660		rc = sk->sk_state == SMC_ACTIVE ? -EISCONN : -EINVAL;
1661		goto out;
1662	case SS_CONNECTING:
1663		if (sk->sk_state == SMC_ACTIVE)
1664			goto connected;
1665		break;
1666	case SS_UNCONNECTED:
1667		sock->state = SS_CONNECTING;
1668		break;
1669	}
1670
1671	switch (sk->sk_state) {
1672	default:
1673		goto out;
1674	case SMC_CLOSED:
1675		rc = sock_error(sk) ? : -ECONNABORTED;
1676		sock->state = SS_UNCONNECTED;
1677		goto out;
1678	case SMC_ACTIVE:
1679		rc = -EISCONN;
1680		goto out;
1681	case SMC_INIT:
1682		break;
1683	}
1684
1685	smc_copy_sock_settings_to_clc(smc);
1686	tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1687	if (smc->connect_nonblock) {
1688		rc = -EALREADY;
1689		goto out;
1690	}
1691	rc = kernel_connect(smc->clcsock, addr, alen, flags);
1692	if (rc && rc != -EINPROGRESS)
1693		goto out;
1694
1695	if (smc->use_fallback) {
1696		sock->state = rc ? SS_CONNECTING : SS_CONNECTED;
1697		goto out;
1698	}
1699	sock_hold(&smc->sk); /* sock put in passive closing */
1700	if (flags & O_NONBLOCK) {
1701		if (queue_work(smc_hs_wq, &smc->connect_work))
1702			smc->connect_nonblock = 1;
1703		rc = -EINPROGRESS;
1704		goto out;
1705	} else {
1706		rc = __smc_connect(smc);
1707		if (rc < 0)
1708			goto out;
1709	}
1710
1711connected:
1712	rc = 0;
1713	sock->state = SS_CONNECTED;
1714out:
1715	release_sock(sk);
1716out_err:
1717	return rc;
1718}
1719
1720static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
1721{
1722	struct socket *new_clcsock = NULL;
1723	struct sock *lsk = &lsmc->sk;
1724	struct sock *new_sk;
1725	int rc = -EINVAL;
1726
1727	release_sock(lsk);
1728	new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
1729	if (!new_sk) {
1730		rc = -ENOMEM;
1731		lsk->sk_err = ENOMEM;
1732		*new_smc = NULL;
1733		lock_sock(lsk);
1734		goto out;
1735	}
1736	*new_smc = smc_sk(new_sk);
1737
1738	mutex_lock(&lsmc->clcsock_release_lock);
1739	if (lsmc->clcsock)
1740		rc = kernel_accept(lsmc->clcsock, &new_clcsock, SOCK_NONBLOCK);
1741	mutex_unlock(&lsmc->clcsock_release_lock);
1742	lock_sock(lsk);
1743	if  (rc < 0 && rc != -EAGAIN)
1744		lsk->sk_err = -rc;
1745	if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
1746		new_sk->sk_prot->unhash(new_sk);
1747		if (new_clcsock)
1748			sock_release(new_clcsock);
1749		new_sk->sk_state = SMC_CLOSED;
1750		smc_sock_set_flag(new_sk, SOCK_DEAD);
1751		sock_put(new_sk); /* final */
1752		*new_smc = NULL;
1753		goto out;
1754	}
1755
1756	/* new clcsock has inherited the smc listen-specific sk_data_ready
1757	 * function; switch it back to the original sk_data_ready function
1758	 */
1759	new_clcsock->sk->sk_data_ready = lsmc->clcsk_data_ready;
1760
1761	/* if new clcsock has also inherited the fallback-specific callback
1762	 * functions, switch them back to the original ones.
1763	 */
1764	if (lsmc->use_fallback) {
1765		if (lsmc->clcsk_state_change)
1766			new_clcsock->sk->sk_state_change = lsmc->clcsk_state_change;
1767		if (lsmc->clcsk_write_space)
1768			new_clcsock->sk->sk_write_space = lsmc->clcsk_write_space;
1769		if (lsmc->clcsk_error_report)
1770			new_clcsock->sk->sk_error_report = lsmc->clcsk_error_report;
1771	}
1772
1773	(*new_smc)->clcsock = new_clcsock;
1774out:
1775	return rc;
1776}
1777
1778/* add a just created sock to the accept queue of the listen sock as
1779 * candidate for a following socket accept call from user space
1780 */
1781static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
1782{
1783	struct smc_sock *par = smc_sk(parent);
1784
1785	sock_hold(sk); /* sock_put in smc_accept_unlink () */
1786	spin_lock(&par->accept_q_lock);
1787	list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
1788	spin_unlock(&par->accept_q_lock);
1789	sk_acceptq_added(parent);
1790}
1791
1792/* remove a socket from the accept queue of its parental listening socket */
1793static void smc_accept_unlink(struct sock *sk)
1794{
1795	struct smc_sock *par = smc_sk(sk)->listen_smc;
1796
1797	spin_lock(&par->accept_q_lock);
1798	list_del_init(&smc_sk(sk)->accept_q);
1799	spin_unlock(&par->accept_q_lock);
1800	sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
1801	sock_put(sk); /* sock_hold in smc_accept_enqueue */
1802}
1803
1804/* remove a sock from the accept queue to bind it to a new socket created
1805 * for a socket accept call from user space
1806 */
1807struct sock *smc_accept_dequeue(struct sock *parent,
1808				struct socket *new_sock)
1809{
1810	struct smc_sock *isk, *n;
1811	struct sock *new_sk;
1812
1813	list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
1814		new_sk = (struct sock *)isk;
1815
1816		smc_accept_unlink(new_sk);
1817		if (new_sk->sk_state == SMC_CLOSED) {
1818			new_sk->sk_prot->unhash(new_sk);
1819			if (isk->clcsock) {
1820				sock_release(isk->clcsock);
1821				isk->clcsock = NULL;
1822			}
1823			sock_put(new_sk); /* final */
1824			continue;
1825		}
1826		if (new_sock) {
1827			sock_graft(new_sk, new_sock);
1828			new_sock->state = SS_CONNECTED;
1829			if (isk->use_fallback) {
1830				smc_sk(new_sk)->clcsock->file = new_sock->file;
1831				isk->clcsock->file->private_data = isk->clcsock;
1832			}
1833		}
1834		return new_sk;
1835	}
1836	return NULL;
1837}
1838
1839/* clean up for a created but never accepted sock */
1840void smc_close_non_accepted(struct sock *sk)
1841{
1842	struct smc_sock *smc = smc_sk(sk);
1843
1844	sock_hold(sk); /* sock_put below */
1845	lock_sock(sk);
1846	if (!sk->sk_lingertime)
1847		/* wait for peer closing */
1848		WRITE_ONCE(sk->sk_lingertime, SMC_MAX_STREAM_WAIT_TIMEOUT);
1849	__smc_release(smc);
1850	release_sock(sk);
1851	sock_put(sk); /* sock_hold above */
1852	sock_put(sk); /* final sock_put */
1853}
1854
1855static int smcr_serv_conf_first_link(struct smc_sock *smc)
1856{
1857	struct smc_link *link = smc->conn.lnk;
1858	struct smc_llc_qentry *qentry;
1859	int rc;
1860
1861	/* reg the sndbuf if it was vzalloced*/
1862	if (smc->conn.sndbuf_desc->is_vm) {
1863		if (smcr_link_reg_buf(link, smc->conn.sndbuf_desc))
1864			return SMC_CLC_DECL_ERR_REGBUF;
1865	}
1866
1867	/* reg the rmb */
1868	if (smcr_link_reg_buf(link, smc->conn.rmb_desc))
1869		return SMC_CLC_DECL_ERR_REGBUF;
1870
1871	/* send CONFIRM LINK request to client over the RoCE fabric */
1872	rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1873	if (rc < 0)
1874		return SMC_CLC_DECL_TIMEOUT_CL;
1875
1876	/* receive CONFIRM LINK response from client over the RoCE fabric */
1877	qentry = smc_llc_wait(link->lgr, link, SMC_LLC_WAIT_TIME,
1878			      SMC_LLC_CONFIRM_LINK);
1879	if (!qentry) {
1880		struct smc_clc_msg_decline dclc;
1881
1882		rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1883				      SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1884		return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1885	}
1886	smc_llc_save_peer_uid(qentry);
1887	rc = smc_llc_eval_conf_link(qentry, SMC_LLC_RESP);
1888	smc_llc_flow_qentry_del(&link->lgr->llc_flow_lcl);
1889	if (rc)
1890		return SMC_CLC_DECL_RMBE_EC;
1891
1892	/* confirm_rkey is implicit on 1st contact */
1893	smc->conn.rmb_desc->is_conf_rkey = true;
1894
1895	smc_llc_link_active(link);
1896	smcr_lgr_set_type(link->lgr, SMC_LGR_SINGLE);
1897
1898	if (link->lgr->max_links > 1) {
1899		down_write(&link->lgr->llc_conf_mutex);
1900		/* initial contact - try to establish second link */
1901		smc_llc_srv_add_link(link, NULL);
1902		up_write(&link->lgr->llc_conf_mutex);
1903	}
1904	return 0;
1905}
1906
1907/* listen worker: finish */
1908static void smc_listen_out(struct smc_sock *new_smc)
1909{
1910	struct smc_sock *lsmc = new_smc->listen_smc;
1911	struct sock *newsmcsk = &new_smc->sk;
1912
1913	if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
1914		atomic_dec(&lsmc->queued_smc_hs);
1915
1916	if (lsmc->sk.sk_state == SMC_LISTEN) {
1917		lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1918		smc_accept_enqueue(&lsmc->sk, newsmcsk);
1919		release_sock(&lsmc->sk);
1920	} else { /* no longer listening */
1921		smc_close_non_accepted(newsmcsk);
1922	}
1923
1924	/* Wake up accept */
1925	lsmc->sk.sk_data_ready(&lsmc->sk);
1926	sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1927}
1928
1929/* listen worker: finish in state connected */
1930static void smc_listen_out_connected(struct smc_sock *new_smc)
1931{
1932	struct sock *newsmcsk = &new_smc->sk;
1933
1934	if (newsmcsk->sk_state == SMC_INIT)
1935		newsmcsk->sk_state = SMC_ACTIVE;
1936
1937	smc_listen_out(new_smc);
1938}
1939
1940/* listen worker: finish in error state */
1941static void smc_listen_out_err(struct smc_sock *new_smc)
1942{
1943	struct sock *newsmcsk = &new_smc->sk;
1944	struct net *net = sock_net(newsmcsk);
1945
1946	this_cpu_inc(net->smc.smc_stats->srv_hshake_err_cnt);
1947	if (newsmcsk->sk_state == SMC_INIT)
1948		sock_put(&new_smc->sk); /* passive closing */
1949	newsmcsk->sk_state = SMC_CLOSED;
1950
1951	smc_listen_out(new_smc);
1952}
1953
1954/* listen worker: decline and fall back if possible */
1955static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1956			       int local_first, u8 version)
1957{
1958	/* RDMA setup failed, switch back to TCP */
1959	smc_conn_abort(new_smc, local_first);
1960	if (reason_code < 0 ||
1961	    smc_switch_to_fallback(new_smc, reason_code)) {
1962		/* error, no fallback possible */
1963		smc_listen_out_err(new_smc);
1964		return;
1965	}
1966	if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1967		if (smc_clc_send_decline(new_smc, reason_code, version) < 0) {
1968			smc_listen_out_err(new_smc);
1969			return;
1970		}
1971	}
1972	smc_listen_out_connected(new_smc);
1973}
1974
1975/* listen worker: version checking */
1976static int smc_listen_v2_check(struct smc_sock *new_smc,
1977			       struct smc_clc_msg_proposal *pclc,
1978			       struct smc_init_info *ini)
1979{
1980	struct smc_clc_smcd_v2_extension *pclc_smcd_v2_ext;
1981	struct smc_clc_v2_extension *pclc_v2_ext;
1982	int rc = SMC_CLC_DECL_PEERNOSMC;
1983
1984	ini->smc_type_v1 = pclc->hdr.typev1;
1985	ini->smc_type_v2 = pclc->hdr.typev2;
1986	ini->smcd_version = smcd_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1987	ini->smcr_version = smcr_indicated(ini->smc_type_v1) ? SMC_V1 : 0;
1988	if (pclc->hdr.version > SMC_V1) {
1989		if (smcd_indicated(ini->smc_type_v2))
1990			ini->smcd_version |= SMC_V2;
1991		if (smcr_indicated(ini->smc_type_v2))
1992			ini->smcr_version |= SMC_V2;
1993	}
1994	if (!(ini->smcd_version & SMC_V2) && !(ini->smcr_version & SMC_V2)) {
1995		rc = SMC_CLC_DECL_PEERNOSMC;
1996		goto out;
1997	}
1998	pclc_v2_ext = smc_get_clc_v2_ext(pclc);
1999	if (!pclc_v2_ext) {
2000		ini->smcd_version &= ~SMC_V2;
2001		ini->smcr_version &= ~SMC_V2;
2002		rc = SMC_CLC_DECL_NOV2EXT;
2003		goto out;
2004	}
2005	pclc_smcd_v2_ext = smc_get_clc_smcd_v2_ext(pclc_v2_ext);
2006	if (ini->smcd_version & SMC_V2) {
2007		if (!smc_ism_is_v2_capable()) {
2008			ini->smcd_version &= ~SMC_V2;
2009			rc = SMC_CLC_DECL_NOISM2SUPP;
2010		} else if (!pclc_smcd_v2_ext) {
2011			ini->smcd_version &= ~SMC_V2;
2012			rc = SMC_CLC_DECL_NOV2DEXT;
2013		} else if (!pclc_v2_ext->hdr.eid_cnt &&
2014			   !pclc_v2_ext->hdr.flag.seid) {
2015			ini->smcd_version &= ~SMC_V2;
2016			rc = SMC_CLC_DECL_NOUEID;
2017		}
2018	}
2019	if (ini->smcr_version & SMC_V2) {
2020		if (!pclc_v2_ext->hdr.eid_cnt) {
2021			ini->smcr_version &= ~SMC_V2;
2022			rc = SMC_CLC_DECL_NOUEID;
2023		}
2024	}
2025
2026	ini->release_nr = pclc_v2_ext->hdr.flag.release;
2027	if (pclc_v2_ext->hdr.flag.release > SMC_RELEASE)
2028		ini->release_nr = SMC_RELEASE;
2029
2030out:
2031	if (!ini->smcd_version && !ini->smcr_version)
2032		return rc;
2033
2034	return 0;
2035}
2036
2037/* listen worker: check prefixes */
2038static int smc_listen_prfx_check(struct smc_sock *new_smc,
2039				 struct smc_clc_msg_proposal *pclc)
2040{
2041	struct smc_clc_msg_proposal_prefix *pclc_prfx;
2042	struct socket *newclcsock = new_smc->clcsock;
2043
2044	if (pclc->hdr.typev1 == SMC_TYPE_N)
2045		return 0;
2046	pclc_prfx = smc_clc_proposal_get_prefix(pclc);
2047	if (smc_clc_prfx_match(newclcsock, pclc_prfx))
2048		return SMC_CLC_DECL_DIFFPREFIX;
2049
2050	return 0;
2051}
2052
2053/* listen worker: initialize connection and buffers */
2054static int smc_listen_rdma_init(struct smc_sock *new_smc,
2055				struct smc_init_info *ini)
2056{
2057	int rc;
2058
2059	/* allocate connection / link group */
2060	rc = smc_conn_create(new_smc, ini);
2061	if (rc)
2062		return rc;
2063
2064	/* create send buffer and rmb */
2065	if (smc_buf_create(new_smc, false)) {
2066		smc_conn_abort(new_smc, ini->first_contact_local);
2067		return SMC_CLC_DECL_MEM;
2068	}
2069
2070	return 0;
2071}
2072
2073/* listen worker: initialize connection and buffers for SMC-D */
2074static int smc_listen_ism_init(struct smc_sock *new_smc,
2075			       struct smc_init_info *ini)
2076{
2077	int rc;
2078
2079	rc = smc_conn_create(new_smc, ini);
2080	if (rc)
2081		return rc;
2082
2083	/* Create send and receive buffers */
2084	rc = smc_buf_create(new_smc, true);
2085	if (rc) {
2086		smc_conn_abort(new_smc, ini->first_contact_local);
2087		return (rc == -ENOSPC) ? SMC_CLC_DECL_MAX_DMB :
2088					 SMC_CLC_DECL_MEM;
2089	}
2090
2091	return 0;
2092}
2093
2094static bool smc_is_already_selected(struct smcd_dev *smcd,
2095				    struct smc_init_info *ini,
2096				    int matches)
2097{
2098	int i;
2099
2100	for (i = 0; i < matches; i++)
2101		if (smcd == ini->ism_dev[i])
2102			return true;
2103
2104	return false;
2105}
2106
2107/* check for ISM devices matching proposed ISM devices */
2108static void smc_check_ism_v2_match(struct smc_init_info *ini,
2109				   u16 proposed_chid, u64 proposed_gid,
2110				   unsigned int *matches)
2111{
2112	struct smcd_dev *smcd;
2113
2114	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2115		if (smcd->going_away)
2116			continue;
2117		if (smc_is_already_selected(smcd, ini, *matches))
2118			continue;
2119		if (smc_ism_get_chid(smcd) == proposed_chid &&
2120		    !smc_ism_cantalk(proposed_gid, ISM_RESERVED_VLANID, smcd)) {
2121			ini->ism_peer_gid[*matches] = proposed_gid;
2122			ini->ism_dev[*matches] = smcd;
2123			(*matches)++;
2124			break;
2125		}
2126	}
2127}
2128
2129static void smc_find_ism_store_rc(u32 rc, struct smc_init_info *ini)
2130{
2131	if (!ini->rc)
2132		ini->rc = rc;
2133}
2134
2135static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc,
2136					struct smc_clc_msg_proposal *pclc,
2137					struct smc_init_info *ini)
2138{
2139	struct smc_clc_smcd_v2_extension *smcd_v2_ext;
2140	struct smc_clc_v2_extension *smc_v2_ext;
2141	struct smc_clc_msg_smcd *pclc_smcd;
2142	unsigned int matches = 0;
2143	u8 smcd_version;
2144	u8 *eid = NULL;
2145	int i, rc;
2146
2147	if (!(ini->smcd_version & SMC_V2) || !smcd_indicated(ini->smc_type_v2))
2148		goto not_found;
2149
2150	pclc_smcd = smc_get_clc_msg_smcd(pclc);
2151	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2152	smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext);
2153
2154	mutex_lock(&smcd_dev_list.mutex);
2155	if (pclc_smcd->ism.chid)
2156		/* check for ISM device matching proposed native ISM device */
2157		smc_check_ism_v2_match(ini, ntohs(pclc_smcd->ism.chid),
2158				       ntohll(pclc_smcd->ism.gid), &matches);
2159	for (i = 1; i <= smc_v2_ext->hdr.ism_gid_cnt; i++) {
2160		/* check for ISM devices matching proposed non-native ISM
2161		 * devices
2162		 */
2163		smc_check_ism_v2_match(ini,
2164				       ntohs(smcd_v2_ext->gidchid[i - 1].chid),
2165				       ntohll(smcd_v2_ext->gidchid[i - 1].gid),
2166				       &matches);
2167	}
2168	mutex_unlock(&smcd_dev_list.mutex);
2169
2170	if (!ini->ism_dev[0]) {
2171		smc_find_ism_store_rc(SMC_CLC_DECL_NOSMCD2DEV, ini);
2172		goto not_found;
2173	}
2174
2175	smc_ism_get_system_eid(&eid);
2176	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext,
2177			       smcd_v2_ext->system_eid, eid))
2178		goto not_found;
2179
2180	/* separate - outside the smcd_dev_list.lock */
2181	smcd_version = ini->smcd_version;
2182	for (i = 0; i < matches; i++) {
2183		ini->smcd_version = SMC_V2;
2184		ini->is_smcd = true;
2185		ini->ism_selected = i;
2186		rc = smc_listen_ism_init(new_smc, ini);
2187		if (rc) {
2188			smc_find_ism_store_rc(rc, ini);
2189			/* try next active ISM device */
2190			continue;
2191		}
2192		return; /* matching and usable V2 ISM device found */
2193	}
2194	/* no V2 ISM device could be initialized */
2195	ini->smcd_version = smcd_version;	/* restore original value */
2196	ini->negotiated_eid[0] = 0;
2197
2198not_found:
2199	ini->smcd_version &= ~SMC_V2;
2200	ini->ism_dev[0] = NULL;
2201	ini->is_smcd = false;
2202}
2203
2204static void smc_find_ism_v1_device_serv(struct smc_sock *new_smc,
2205					struct smc_clc_msg_proposal *pclc,
2206					struct smc_init_info *ini)
2207{
2208	struct smc_clc_msg_smcd *pclc_smcd = smc_get_clc_msg_smcd(pclc);
2209	int rc = 0;
2210
2211	/* check if ISM V1 is available */
2212	if (!(ini->smcd_version & SMC_V1) || !smcd_indicated(ini->smc_type_v1))
2213		goto not_found;
2214	ini->is_smcd = true; /* prepare ISM check */
2215	ini->ism_peer_gid[0] = ntohll(pclc_smcd->ism.gid);
2216	rc = smc_find_ism_device(new_smc, ini);
2217	if (rc)
2218		goto not_found;
2219	ini->ism_selected = 0;
2220	rc = smc_listen_ism_init(new_smc, ini);
2221	if (!rc)
2222		return;		/* V1 ISM device found */
2223
2224not_found:
2225	smc_find_ism_store_rc(rc, ini);
2226	ini->smcd_version &= ~SMC_V1;
2227	ini->ism_dev[0] = NULL;
2228	ini->is_smcd = false;
2229}
2230
2231/* listen worker: register buffers */
2232static int smc_listen_rdma_reg(struct smc_sock *new_smc, bool local_first)
2233{
2234	struct smc_connection *conn = &new_smc->conn;
2235
2236	if (!local_first) {
2237		/* reg sendbufs if they were vzalloced */
2238		if (conn->sndbuf_desc->is_vm) {
2239			if (smcr_lgr_reg_sndbufs(conn->lnk,
2240						 conn->sndbuf_desc))
2241				return SMC_CLC_DECL_ERR_REGBUF;
2242		}
2243		if (smcr_lgr_reg_rmbs(conn->lnk, conn->rmb_desc))
2244			return SMC_CLC_DECL_ERR_REGBUF;
2245	}
2246
2247	return 0;
2248}
2249
2250static void smc_find_rdma_v2_device_serv(struct smc_sock *new_smc,
2251					 struct smc_clc_msg_proposal *pclc,
2252					 struct smc_init_info *ini)
2253{
2254	struct smc_clc_v2_extension *smc_v2_ext;
2255	u8 smcr_version;
2256	int rc;
2257
2258	if (!(ini->smcr_version & SMC_V2) || !smcr_indicated(ini->smc_type_v2))
2259		goto not_found;
2260
2261	smc_v2_ext = smc_get_clc_v2_ext(pclc);
2262	if (!smc_clc_match_eid(ini->negotiated_eid, smc_v2_ext, NULL, NULL))
2263		goto not_found;
2264
2265	/* prepare RDMA check */
2266	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2267	memcpy(ini->peer_gid, smc_v2_ext->roce, SMC_GID_SIZE);
2268	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2269	ini->check_smcrv2 = true;
2270	ini->smcrv2.clc_sk = new_smc->clcsock->sk;
2271	ini->smcrv2.saddr = new_smc->clcsock->sk->sk_rcv_saddr;
2272	ini->smcrv2.daddr = smc_ib_gid_to_ipv4(smc_v2_ext->roce);
2273	rc = smc_find_rdma_device(new_smc, ini);
2274	if (rc) {
2275		smc_find_ism_store_rc(rc, ini);
2276		goto not_found;
2277	}
2278	if (!ini->smcrv2.uses_gateway)
2279		memcpy(ini->smcrv2.nexthop_mac, pclc->lcl.mac, ETH_ALEN);
2280
2281	smcr_version = ini->smcr_version;
2282	ini->smcr_version = SMC_V2;
2283	rc = smc_listen_rdma_init(new_smc, ini);
2284	if (!rc) {
2285		rc = smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2286		if (rc)
2287			smc_conn_abort(new_smc, ini->first_contact_local);
2288	}
2289	if (!rc)
2290		return;
2291	ini->smcr_version = smcr_version;
2292	smc_find_ism_store_rc(rc, ini);
2293
2294not_found:
2295	ini->smcr_version &= ~SMC_V2;
2296	ini->smcrv2.ib_dev_v2 = NULL;
2297	ini->check_smcrv2 = false;
2298}
2299
2300static int smc_find_rdma_v1_device_serv(struct smc_sock *new_smc,
2301					struct smc_clc_msg_proposal *pclc,
2302					struct smc_init_info *ini)
2303{
2304	int rc;
2305
2306	if (!(ini->smcr_version & SMC_V1) || !smcr_indicated(ini->smc_type_v1))
2307		return SMC_CLC_DECL_NOSMCDEV;
2308
2309	/* prepare RDMA check */
2310	memcpy(ini->peer_systemid, pclc->lcl.id_for_peer, SMC_SYSTEMID_LEN);
2311	memcpy(ini->peer_gid, pclc->lcl.gid, SMC_GID_SIZE);
2312	memcpy(ini->peer_mac, pclc->lcl.mac, ETH_ALEN);
2313	rc = smc_find_rdma_device(new_smc, ini);
2314	if (rc) {
2315		/* no RDMA device found */
2316		return SMC_CLC_DECL_NOSMCDEV;
2317	}
2318	rc = smc_listen_rdma_init(new_smc, ini);
2319	if (rc)
2320		return rc;
2321	return smc_listen_rdma_reg(new_smc, ini->first_contact_local);
2322}
2323
2324/* determine the local device matching to proposal */
2325static int smc_listen_find_device(struct smc_sock *new_smc,
2326				  struct smc_clc_msg_proposal *pclc,
2327				  struct smc_init_info *ini)
2328{
2329	int prfx_rc;
2330
2331	/* check for ISM device matching V2 proposed device */
2332	smc_find_ism_v2_device_serv(new_smc, pclc, ini);
2333	if (ini->ism_dev[0])
2334		return 0;
2335
2336	/* check for matching IP prefix and subnet length (V1) */
2337	prfx_rc = smc_listen_prfx_check(new_smc, pclc);
2338	if (prfx_rc)
2339		smc_find_ism_store_rc(prfx_rc, ini);
2340
2341	/* get vlan id from IP device */
2342	if (smc_vlan_by_tcpsk(new_smc->clcsock, ini))
2343		return ini->rc ?: SMC_CLC_DECL_GETVLANERR;
2344
2345	/* check for ISM device matching V1 proposed device */
2346	if (!prfx_rc)
2347		smc_find_ism_v1_device_serv(new_smc, pclc, ini);
2348	if (ini->ism_dev[0])
2349		return 0;
2350
2351	if (!smcr_indicated(pclc->hdr.typev1) &&
2352	    !smcr_indicated(pclc->hdr.typev2))
2353		/* skip RDMA and decline */
2354		return ini->rc ?: SMC_CLC_DECL_NOSMCDDEV;
2355
2356	/* check if RDMA V2 is available */
2357	smc_find_rdma_v2_device_serv(new_smc, pclc, ini);
2358	if (ini->smcrv2.ib_dev_v2)
2359		return 0;
2360
2361	/* check if RDMA V1 is available */
2362	if (!prfx_rc) {
2363		int rc;
2364
2365		rc = smc_find_rdma_v1_device_serv(new_smc, pclc, ini);
2366		smc_find_ism_store_rc(rc, ini);
2367		return (!rc) ? 0 : ini->rc;
2368	}
2369	return prfx_rc;
2370}
2371
2372/* listen worker: finish RDMA setup */
2373static int smc_listen_rdma_finish(struct smc_sock *new_smc,
2374				  struct smc_clc_msg_accept_confirm *cclc,
2375				  bool local_first,
2376				  struct smc_init_info *ini)
2377{
2378	struct smc_link *link = new_smc->conn.lnk;
2379	int reason_code = 0;
2380
2381	if (local_first)
2382		smc_link_save_peer_info(link, cclc, ini);
2383
2384	if (smc_rmb_rtoken_handling(&new_smc->conn, link, cclc))
2385		return SMC_CLC_DECL_ERR_RTOK;
2386
2387	if (local_first) {
2388		if (smc_ib_ready_link(link))
2389			return SMC_CLC_DECL_ERR_RDYLNK;
2390		/* QP confirmation over RoCE fabric */
2391		smc_llc_flow_initiate(link->lgr, SMC_LLC_FLOW_ADD_LINK);
2392		reason_code = smcr_serv_conf_first_link(new_smc);
2393		smc_llc_flow_stop(link->lgr, &link->lgr->llc_flow_lcl);
2394	}
2395	return reason_code;
2396}
2397
2398/* setup for connection of server */
2399static void smc_listen_work(struct work_struct *work)
2400{
2401	struct smc_sock *new_smc = container_of(work, struct smc_sock,
2402						smc_listen_work);
2403	struct socket *newclcsock = new_smc->clcsock;
2404	struct smc_clc_msg_accept_confirm *cclc;
2405	struct smc_clc_msg_proposal_area *buf;
2406	struct smc_clc_msg_proposal *pclc;
2407	struct smc_init_info *ini = NULL;
2408	u8 proposal_version = SMC_V1;
2409	u8 accept_version;
2410	int rc = 0;
2411
2412	if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
2413		return smc_listen_out_err(new_smc);
2414
2415	if (new_smc->use_fallback) {
2416		smc_listen_out_connected(new_smc);
2417		return;
2418	}
2419
2420	/* check if peer is smc capable */
2421	if (!tcp_sk(newclcsock->sk)->syn_smc) {
2422		rc = smc_switch_to_fallback(new_smc, SMC_CLC_DECL_PEERNOSMC);
2423		if (rc)
2424			smc_listen_out_err(new_smc);
2425		else
2426			smc_listen_out_connected(new_smc);
2427		return;
2428	}
2429
2430	/* do inband token exchange -
2431	 * wait for and receive SMC Proposal CLC message
2432	 */
2433	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
2434	if (!buf) {
2435		rc = SMC_CLC_DECL_MEM;
2436		goto out_decl;
2437	}
2438	pclc = (struct smc_clc_msg_proposal *)buf;
2439	rc = smc_clc_wait_msg(new_smc, pclc, sizeof(*buf),
2440			      SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
2441	if (rc)
2442		goto out_decl;
2443
2444	if (pclc->hdr.version > SMC_V1)
2445		proposal_version = SMC_V2;
2446
2447	/* IPSec connections opt out of SMC optimizations */
2448	if (using_ipsec(new_smc)) {
2449		rc = SMC_CLC_DECL_IPSEC;
2450		goto out_decl;
2451	}
2452
2453	ini = kzalloc(sizeof(*ini), GFP_KERNEL);
2454	if (!ini) {
2455		rc = SMC_CLC_DECL_MEM;
2456		goto out_decl;
2457	}
2458
2459	/* initial version checking */
2460	rc = smc_listen_v2_check(new_smc, pclc, ini);
2461	if (rc)
2462		goto out_decl;
2463
2464	rc = smc_clc_srv_v2x_features_validate(pclc, ini);
2465	if (rc)
2466		goto out_decl;
2467
2468	mutex_lock(&smc_server_lgr_pending);
2469	smc_close_init(new_smc);
2470	smc_rx_init(new_smc);
2471	smc_tx_init(new_smc);
2472
2473	/* determine ISM or RoCE device used for connection */
2474	rc = smc_listen_find_device(new_smc, pclc, ini);
2475	if (rc)
2476		goto out_unlock;
2477
2478	/* send SMC Accept CLC message */
2479	accept_version = ini->is_smcd ? ini->smcd_version : ini->smcr_version;
2480	rc = smc_clc_send_accept(new_smc, ini->first_contact_local,
2481				 accept_version, ini->negotiated_eid, ini);
2482	if (rc)
2483		goto out_unlock;
2484
2485	/* SMC-D does not need this lock any more */
2486	if (ini->is_smcd)
2487		mutex_unlock(&smc_server_lgr_pending);
2488
2489	/* receive SMC Confirm CLC message */
2490	memset(buf, 0, sizeof(*buf));
2491	cclc = (struct smc_clc_msg_accept_confirm *)buf;
2492	rc = smc_clc_wait_msg(new_smc, cclc, sizeof(*buf),
2493			      SMC_CLC_CONFIRM, CLC_WAIT_TIME);
2494	if (rc) {
2495		if (!ini->is_smcd)
2496			goto out_unlock;
2497		goto out_decl;
2498	}
2499
2500	rc = smc_clc_v2x_features_confirm_check(cclc, ini);
2501	if (rc) {
2502		if (!ini->is_smcd)
2503			goto out_unlock;
2504		goto out_decl;
2505	}
2506
2507	/* fce smc release version is needed in smc_listen_rdma_finish,
2508	 * so save fce info here.
2509	 */
2510	smc_conn_save_peer_info_fce(new_smc, cclc);
2511
2512	/* finish worker */
2513	if (!ini->is_smcd) {
2514		rc = smc_listen_rdma_finish(new_smc, cclc,
2515					    ini->first_contact_local, ini);
2516		if (rc)
2517			goto out_unlock;
2518		mutex_unlock(&smc_server_lgr_pending);
2519	}
2520	smc_conn_save_peer_info(new_smc, cclc);
2521	smc_listen_out_connected(new_smc);
2522	SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk), ini);
2523	goto out_free;
2524
2525out_unlock:
2526	mutex_unlock(&smc_server_lgr_pending);
2527out_decl:
2528	smc_listen_decline(new_smc, rc, ini ? ini->first_contact_local : 0,
2529			   proposal_version);
2530out_free:
2531	kfree(ini);
2532	kfree(buf);
2533}
2534
2535static void smc_tcp_listen_work(struct work_struct *work)
2536{
2537	struct smc_sock *lsmc = container_of(work, struct smc_sock,
2538					     tcp_listen_work);
2539	struct sock *lsk = &lsmc->sk;
2540	struct smc_sock *new_smc;
2541	int rc = 0;
2542
2543	lock_sock(lsk);
2544	while (lsk->sk_state == SMC_LISTEN) {
2545		rc = smc_clcsock_accept(lsmc, &new_smc);
2546		if (rc) /* clcsock accept queue empty or error */
2547			goto out;
2548		if (!new_smc)
2549			continue;
2550
2551		if (tcp_sk(new_smc->clcsock->sk)->syn_smc)
2552			atomic_inc(&lsmc->queued_smc_hs);
2553
2554		new_smc->listen_smc = lsmc;
2555		new_smc->use_fallback = lsmc->use_fallback;
2556		new_smc->fallback_rsn = lsmc->fallback_rsn;
2557		sock_hold(lsk); /* sock_put in smc_listen_work */
2558		INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
2559		smc_copy_sock_settings_to_smc(new_smc);
2560		sock_hold(&new_smc->sk); /* sock_put in passive closing */
2561		if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work))
2562			sock_put(&new_smc->sk);
2563	}
2564
2565out:
2566	release_sock(lsk);
2567	sock_put(&lsmc->sk); /* sock_hold in smc_clcsock_data_ready() */
2568}
2569
2570static void smc_clcsock_data_ready(struct sock *listen_clcsock)
2571{
2572	struct smc_sock *lsmc;
2573
2574	read_lock_bh(&listen_clcsock->sk_callback_lock);
2575	lsmc = smc_clcsock_user_data(listen_clcsock);
2576	if (!lsmc)
2577		goto out;
2578	lsmc->clcsk_data_ready(listen_clcsock);
2579	if (lsmc->sk.sk_state == SMC_LISTEN) {
2580		sock_hold(&lsmc->sk); /* sock_put in smc_tcp_listen_work() */
2581		if (!queue_work(smc_tcp_ls_wq, &lsmc->tcp_listen_work))
2582			sock_put(&lsmc->sk);
2583	}
2584out:
2585	read_unlock_bh(&listen_clcsock->sk_callback_lock);
2586}
2587
2588static int smc_listen(struct socket *sock, int backlog)
2589{
2590	struct sock *sk = sock->sk;
2591	struct smc_sock *smc;
2592	int rc;
2593
2594	smc = smc_sk(sk);
2595	lock_sock(sk);
2596
2597	rc = -EINVAL;
2598	if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
2599	    smc->connect_nonblock || sock->state != SS_UNCONNECTED)
2600		goto out;
2601
2602	rc = 0;
2603	if (sk->sk_state == SMC_LISTEN) {
2604		sk->sk_max_ack_backlog = backlog;
2605		goto out;
2606	}
2607	/* some socket options are handled in core, so we could not apply
2608	 * them to the clc socket -- copy smc socket options to clc socket
2609	 */
2610	smc_copy_sock_settings_to_clc(smc);
2611	if (!smc->use_fallback)
2612		tcp_sk(smc->clcsock->sk)->syn_smc = 1;
2613
2614	/* save original sk_data_ready function and establish
2615	 * smc-specific sk_data_ready function
2616	 */
2617	write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2618	smc->clcsock->sk->sk_user_data =
2619		(void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY);
2620	smc_clcsock_replace_cb(&smc->clcsock->sk->sk_data_ready,
2621			       smc_clcsock_data_ready, &smc->clcsk_data_ready);
2622	write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2623
2624	/* save original ops */
2625	smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops;
2626
2627	smc->af_ops = *smc->ori_af_ops;
2628	smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock;
2629
2630	inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops;
2631
2632	if (smc->limit_smc_hs)
2633		tcp_sk(smc->clcsock->sk)->smc_hs_congested = smc_hs_congested;
2634
2635	rc = kernel_listen(smc->clcsock, backlog);
2636	if (rc) {
2637		write_lock_bh(&smc->clcsock->sk->sk_callback_lock);
2638		smc_clcsock_restore_cb(&smc->clcsock->sk->sk_data_ready,
2639				       &smc->clcsk_data_ready);
2640		smc->clcsock->sk->sk_user_data = NULL;
2641		write_unlock_bh(&smc->clcsock->sk->sk_callback_lock);
2642		goto out;
2643	}
2644	sk->sk_max_ack_backlog = backlog;
2645	sk->sk_ack_backlog = 0;
2646	sk->sk_state = SMC_LISTEN;
2647
2648out:
2649	release_sock(sk);
2650	return rc;
2651}
2652
2653static int smc_accept(struct socket *sock, struct socket *new_sock,
2654		      int flags, bool kern)
2655{
2656	struct sock *sk = sock->sk, *nsk;
2657	DECLARE_WAITQUEUE(wait, current);
2658	struct smc_sock *lsmc;
2659	long timeo;
2660	int rc = 0;
2661
2662	lsmc = smc_sk(sk);
2663	sock_hold(sk); /* sock_put below */
2664	lock_sock(sk);
2665
2666	if (lsmc->sk.sk_state != SMC_LISTEN) {
2667		rc = -EINVAL;
2668		release_sock(sk);
2669		goto out;
2670	}
2671
2672	/* Wait for an incoming connection */
2673	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
2674	add_wait_queue_exclusive(sk_sleep(sk), &wait);
2675	while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
2676		set_current_state(TASK_INTERRUPTIBLE);
2677		if (!timeo) {
2678			rc = -EAGAIN;
2679			break;
2680		}
2681		release_sock(sk);
2682		timeo = schedule_timeout(timeo);
2683		/* wakeup by sk_data_ready in smc_listen_work() */
2684		sched_annotate_sleep();
2685		lock_sock(sk);
2686		if (signal_pending(current)) {
2687			rc = sock_intr_errno(timeo);
2688			break;
2689		}
2690	}
2691	set_current_state(TASK_RUNNING);
2692	remove_wait_queue(sk_sleep(sk), &wait);
2693
2694	if (!rc)
2695		rc = sock_error(nsk);
2696	release_sock(sk);
2697	if (rc)
2698		goto out;
2699
2700	if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
2701		/* wait till data arrives on the socket */
2702		timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
2703								MSEC_PER_SEC);
2704		if (smc_sk(nsk)->use_fallback) {
2705			struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
2706
2707			lock_sock(clcsk);
2708			if (skb_queue_empty(&clcsk->sk_receive_queue))
2709				sk_wait_data(clcsk, &timeo, NULL);
2710			release_sock(clcsk);
2711		} else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
2712			lock_sock(nsk);
2713			smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
2714			release_sock(nsk);
2715		}
2716	}
2717
2718out:
2719	sock_put(sk); /* sock_hold above */
2720	return rc;
2721}
2722
2723static int smc_getname(struct socket *sock, struct sockaddr *addr,
2724		       int peer)
2725{
2726	struct smc_sock *smc;
2727
2728	if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
2729	    (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
2730		return -ENOTCONN;
2731
2732	smc = smc_sk(sock->sk);
2733
2734	return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
2735}
2736
2737static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2738{
2739	struct sock *sk = sock->sk;
2740	struct smc_sock *smc;
2741	int rc;
2742
2743	smc = smc_sk(sk);
2744	lock_sock(sk);
2745
2746	/* SMC does not support connect with fastopen */
2747	if (msg->msg_flags & MSG_FASTOPEN) {
2748		/* not connected yet, fallback */
2749		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
2750			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
2751			if (rc)
2752				goto out;
2753		} else {
2754			rc = -EINVAL;
2755			goto out;
2756		}
2757	} else if ((sk->sk_state != SMC_ACTIVE) &&
2758		   (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2759		   (sk->sk_state != SMC_INIT)) {
2760		rc = -EPIPE;
2761		goto out;
2762	}
2763
2764	if (smc->use_fallback) {
2765		rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
2766	} else {
2767		rc = smc_tx_sendmsg(smc, msg, len);
2768		SMC_STAT_TX_PAYLOAD(smc, len, rc);
2769	}
2770out:
2771	release_sock(sk);
2772	return rc;
2773}
2774
2775static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2776		       int flags)
2777{
2778	struct sock *sk = sock->sk;
2779	struct smc_sock *smc;
2780	int rc = -ENOTCONN;
2781
2782	smc = smc_sk(sk);
2783	lock_sock(sk);
2784	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
2785		/* socket was connected before, no more data to read */
2786		rc = 0;
2787		goto out;
2788	}
2789	if ((sk->sk_state == SMC_INIT) ||
2790	    (sk->sk_state == SMC_LISTEN) ||
2791	    (sk->sk_state == SMC_CLOSED))
2792		goto out;
2793
2794	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
2795		rc = 0;
2796		goto out;
2797	}
2798
2799	if (smc->use_fallback) {
2800		rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
2801	} else {
2802		msg->msg_namelen = 0;
2803		rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
2804		SMC_STAT_RX_PAYLOAD(smc, rc, rc);
2805	}
2806
2807out:
2808	release_sock(sk);
2809	return rc;
2810}
2811
2812static __poll_t smc_accept_poll(struct sock *parent)
2813{
2814	struct smc_sock *isk = smc_sk(parent);
2815	__poll_t mask = 0;
2816
2817	spin_lock(&isk->accept_q_lock);
2818	if (!list_empty(&isk->accept_q))
2819		mask = EPOLLIN | EPOLLRDNORM;
2820	spin_unlock(&isk->accept_q_lock);
2821
2822	return mask;
2823}
2824
2825static __poll_t smc_poll(struct file *file, struct socket *sock,
2826			     poll_table *wait)
2827{
2828	struct sock *sk = sock->sk;
2829	struct smc_sock *smc;
2830	__poll_t mask = 0;
2831
2832	if (!sk)
2833		return EPOLLNVAL;
2834
2835	smc = smc_sk(sock->sk);
2836	if (smc->use_fallback) {
2837		/* delegate to CLC child sock */
2838		mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
2839		sk->sk_err = smc->clcsock->sk->sk_err;
2840	} else {
2841		if (sk->sk_state != SMC_CLOSED)
2842			sock_poll_wait(file, sock, wait);
2843		if (sk->sk_err)
2844			mask |= EPOLLERR;
2845		if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
2846		    (sk->sk_state == SMC_CLOSED))
2847			mask |= EPOLLHUP;
2848		if (sk->sk_state == SMC_LISTEN) {
2849			/* woken up by sk_data_ready in smc_listen_work() */
2850			mask |= smc_accept_poll(sk);
2851		} else if (smc->use_fallback) { /* as result of connect_work()*/
2852			mask |= smc->clcsock->ops->poll(file, smc->clcsock,
2853							   wait);
2854			sk->sk_err = smc->clcsock->sk->sk_err;
2855		} else {
2856			if ((sk->sk_state != SMC_INIT &&
2857			     atomic_read(&smc->conn.sndbuf_space)) ||
2858			    sk->sk_shutdown & SEND_SHUTDOWN) {
2859				mask |= EPOLLOUT | EPOLLWRNORM;
2860			} else {
2861				sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2862				set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2863			}
2864			if (atomic_read(&smc->conn.bytes_to_rcv))
2865				mask |= EPOLLIN | EPOLLRDNORM;
2866			if (sk->sk_shutdown & RCV_SHUTDOWN)
2867				mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
2868			if (sk->sk_state == SMC_APPCLOSEWAIT1)
2869				mask |= EPOLLIN;
2870			if (smc->conn.urg_state == SMC_URG_VALID)
2871				mask |= EPOLLPRI;
2872		}
2873	}
2874
2875	return mask;
2876}
2877
2878static int smc_shutdown(struct socket *sock, int how)
2879{
2880	struct sock *sk = sock->sk;
2881	bool do_shutdown = true;
2882	struct smc_sock *smc;
2883	int rc = -EINVAL;
2884	int old_state;
2885	int rc1 = 0;
2886
2887	smc = smc_sk(sk);
2888
2889	if ((how < SHUT_RD) || (how > SHUT_RDWR))
2890		return rc;
2891
2892	lock_sock(sk);
2893
2894	if (sock->state == SS_CONNECTING) {
2895		if (sk->sk_state == SMC_ACTIVE)
2896			sock->state = SS_CONNECTED;
2897		else if (sk->sk_state == SMC_PEERCLOSEWAIT1 ||
2898			 sk->sk_state == SMC_PEERCLOSEWAIT2 ||
2899			 sk->sk_state == SMC_APPCLOSEWAIT1 ||
2900			 sk->sk_state == SMC_APPCLOSEWAIT2 ||
2901			 sk->sk_state == SMC_APPFINCLOSEWAIT)
2902			sock->state = SS_DISCONNECTING;
2903	}
2904
2905	rc = -ENOTCONN;
2906	if ((sk->sk_state != SMC_ACTIVE) &&
2907	    (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
2908	    (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
2909	    (sk->sk_state != SMC_APPCLOSEWAIT1) &&
2910	    (sk->sk_state != SMC_APPCLOSEWAIT2) &&
2911	    (sk->sk_state != SMC_APPFINCLOSEWAIT))
2912		goto out;
2913	if (smc->use_fallback) {
2914		rc = kernel_sock_shutdown(smc->clcsock, how);
2915		sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
2916		if (sk->sk_shutdown == SHUTDOWN_MASK) {
2917			sk->sk_state = SMC_CLOSED;
2918			sk->sk_socket->state = SS_UNCONNECTED;
2919			sock_put(sk);
2920		}
2921		goto out;
2922	}
2923	switch (how) {
2924	case SHUT_RDWR:		/* shutdown in both directions */
2925		old_state = sk->sk_state;
2926		rc = smc_close_active(smc);
2927		if (old_state == SMC_ACTIVE &&
2928		    sk->sk_state == SMC_PEERCLOSEWAIT1)
2929			do_shutdown = false;
2930		break;
2931	case SHUT_WR:
2932		rc = smc_close_shutdown_write(smc);
2933		break;
2934	case SHUT_RD:
2935		rc = 0;
2936		/* nothing more to do because peer is not involved */
2937		break;
2938	}
2939	if (do_shutdown && smc->clcsock)
2940		rc1 = kernel_sock_shutdown(smc->clcsock, how);
2941	/* map sock_shutdown_cmd constants to sk_shutdown value range */
2942	sk->sk_shutdown |= how + 1;
2943
2944	if (sk->sk_state == SMC_CLOSED)
2945		sock->state = SS_UNCONNECTED;
2946	else
2947		sock->state = SS_DISCONNECTING;
2948out:
2949	release_sock(sk);
2950	return rc ? rc : rc1;
2951}
2952
2953static int __smc_getsockopt(struct socket *sock, int level, int optname,
2954			    char __user *optval, int __user *optlen)
2955{
2956	struct smc_sock *smc;
2957	int val, len;
2958
2959	smc = smc_sk(sock->sk);
2960
2961	if (get_user(len, optlen))
2962		return -EFAULT;
2963
2964	len = min_t(int, len, sizeof(int));
2965
2966	if (len < 0)
2967		return -EINVAL;
2968
2969	switch (optname) {
2970	case SMC_LIMIT_HS:
2971		val = smc->limit_smc_hs;
2972		break;
2973	default:
2974		return -EOPNOTSUPP;
2975	}
2976
2977	if (put_user(len, optlen))
2978		return -EFAULT;
2979	if (copy_to_user(optval, &val, len))
2980		return -EFAULT;
2981
2982	return 0;
2983}
2984
2985static int __smc_setsockopt(struct socket *sock, int level, int optname,
2986			    sockptr_t optval, unsigned int optlen)
2987{
2988	struct sock *sk = sock->sk;
2989	struct smc_sock *smc;
2990	int val, rc;
2991
2992	smc = smc_sk(sk);
2993
2994	lock_sock(sk);
2995	switch (optname) {
2996	case SMC_LIMIT_HS:
2997		if (optlen < sizeof(int)) {
2998			rc = -EINVAL;
2999			break;
3000		}
3001		if (copy_from_sockptr(&val, optval, sizeof(int))) {
3002			rc = -EFAULT;
3003			break;
3004		}
3005
3006		smc->limit_smc_hs = !!val;
3007		rc = 0;
3008		break;
3009	default:
3010		rc = -EOPNOTSUPP;
3011		break;
3012	}
3013	release_sock(sk);
3014
3015	return rc;
3016}
3017
3018static int smc_setsockopt(struct socket *sock, int level, int optname,
3019			  sockptr_t optval, unsigned int optlen)
3020{
3021	struct sock *sk = sock->sk;
3022	struct smc_sock *smc;
3023	int val, rc;
3024
3025	if (level == SOL_TCP && optname == TCP_ULP)
3026		return -EOPNOTSUPP;
3027	else if (level == SOL_SMC)
3028		return __smc_setsockopt(sock, level, optname, optval, optlen);
3029
3030	smc = smc_sk(sk);
3031
3032	/* generic setsockopts reaching us here always apply to the
3033	 * CLC socket
3034	 */
3035	mutex_lock(&smc->clcsock_release_lock);
3036	if (!smc->clcsock) {
3037		mutex_unlock(&smc->clcsock_release_lock);
3038		return -EBADF;
3039	}
3040	if (unlikely(!smc->clcsock->ops->setsockopt))
3041		rc = -EOPNOTSUPP;
3042	else
3043		rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
3044						   optval, optlen);
3045	if (smc->clcsock->sk->sk_err) {
3046		sk->sk_err = smc->clcsock->sk->sk_err;
3047		sk_error_report(sk);
3048	}
3049	mutex_unlock(&smc->clcsock_release_lock);
3050
3051	if (optlen < sizeof(int))
3052		return -EINVAL;
3053	if (copy_from_sockptr(&val, optval, sizeof(int)))
3054		return -EFAULT;
3055
3056	lock_sock(sk);
3057	if (rc || smc->use_fallback)
3058		goto out;
3059	switch (optname) {
3060	case TCP_FASTOPEN:
3061	case TCP_FASTOPEN_CONNECT:
3062	case TCP_FASTOPEN_KEY:
3063	case TCP_FASTOPEN_NO_COOKIE:
3064		/* option not supported by SMC */
3065		if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
3066			rc = smc_switch_to_fallback(smc, SMC_CLC_DECL_OPTUNSUPP);
3067		} else {
3068			rc = -EINVAL;
3069		}
3070		break;
3071	case TCP_NODELAY:
3072		if (sk->sk_state != SMC_INIT &&
3073		    sk->sk_state != SMC_LISTEN &&
3074		    sk->sk_state != SMC_CLOSED) {
3075			if (val) {
3076				SMC_STAT_INC(smc, ndly_cnt);
3077				smc_tx_pending(&smc->conn);
3078				cancel_delayed_work(&smc->conn.tx_work);
3079			}
3080		}
3081		break;
3082	case TCP_CORK:
3083		if (sk->sk_state != SMC_INIT &&
3084		    sk->sk_state != SMC_LISTEN &&
3085		    sk->sk_state != SMC_CLOSED) {
3086			if (!val) {
3087				SMC_STAT_INC(smc, cork_cnt);
3088				smc_tx_pending(&smc->conn);
3089				cancel_delayed_work(&smc->conn.tx_work);
3090			}
3091		}
3092		break;
3093	case TCP_DEFER_ACCEPT:
3094		smc->sockopt_defer_accept = val;
3095		break;
3096	default:
3097		break;
3098	}
3099out:
3100	release_sock(sk);
3101
3102	return rc;
3103}
3104
3105static int smc_getsockopt(struct socket *sock, int level, int optname,
3106			  char __user *optval, int __user *optlen)
3107{
3108	struct smc_sock *smc;
3109	int rc;
3110
3111	if (level == SOL_SMC)
3112		return __smc_getsockopt(sock, level, optname, optval, optlen);
3113
3114	smc = smc_sk(sock->sk);
3115	mutex_lock(&smc->clcsock_release_lock);
3116	if (!smc->clcsock) {
3117		mutex_unlock(&smc->clcsock_release_lock);
3118		return -EBADF;
3119	}
3120	/* socket options apply to the CLC socket */
3121	if (unlikely(!smc->clcsock->ops->getsockopt)) {
3122		mutex_unlock(&smc->clcsock_release_lock);
3123		return -EOPNOTSUPP;
3124	}
3125	rc = smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
3126					   optval, optlen);
3127	mutex_unlock(&smc->clcsock_release_lock);
3128	return rc;
3129}
3130
3131static int smc_ioctl(struct socket *sock, unsigned int cmd,
3132		     unsigned long arg)
3133{
3134	union smc_host_cursor cons, urg;
3135	struct smc_connection *conn;
3136	struct smc_sock *smc;
3137	int answ;
3138
3139	smc = smc_sk(sock->sk);
3140	conn = &smc->conn;
3141	lock_sock(&smc->sk);
3142	if (smc->use_fallback) {
3143		if (!smc->clcsock) {
3144			release_sock(&smc->sk);
3145			return -EBADF;
3146		}
3147		answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
3148		release_sock(&smc->sk);
3149		return answ;
3150	}
3151	switch (cmd) {
3152	case SIOCINQ: /* same as FIONREAD */
3153		if (smc->sk.sk_state == SMC_LISTEN) {
3154			release_sock(&smc->sk);
3155			return -EINVAL;
3156		}
3157		if (smc->sk.sk_state == SMC_INIT ||
3158		    smc->sk.sk_state == SMC_CLOSED)
3159			answ = 0;
3160		else
3161			answ = atomic_read(&smc->conn.bytes_to_rcv);
3162		break;
3163	case SIOCOUTQ:
3164		/* output queue size (not send + not acked) */
3165		if (smc->sk.sk_state == SMC_LISTEN) {
3166			release_sock(&smc->sk);
3167			return -EINVAL;
3168		}
3169		if (smc->sk.sk_state == SMC_INIT ||
3170		    smc->sk.sk_state == SMC_CLOSED)
3171			answ = 0;
3172		else
3173			answ = smc->conn.sndbuf_desc->len -
3174					atomic_read(&smc->conn.sndbuf_space);
3175		break;
3176	case SIOCOUTQNSD:
3177		/* output queue size (not send only) */
3178		if (smc->sk.sk_state == SMC_LISTEN) {
3179			release_sock(&smc->sk);
3180			return -EINVAL;
3181		}
3182		if (smc->sk.sk_state == SMC_INIT ||
3183		    smc->sk.sk_state == SMC_CLOSED)
3184			answ = 0;
3185		else
3186			answ = smc_tx_prepared_sends(&smc->conn);
3187		break;
3188	case SIOCATMARK:
3189		if (smc->sk.sk_state == SMC_LISTEN) {
3190			release_sock(&smc->sk);
3191			return -EINVAL;
3192		}
3193		if (smc->sk.sk_state == SMC_INIT ||
3194		    smc->sk.sk_state == SMC_CLOSED) {
3195			answ = 0;
3196		} else {
3197			smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
3198			smc_curs_copy(&urg, &conn->urg_curs, conn);
3199			answ = smc_curs_diff(conn->rmb_desc->len,
3200					     &cons, &urg) == 1;
3201		}
3202		break;
3203	default:
3204		release_sock(&smc->sk);
3205		return -ENOIOCTLCMD;
3206	}
3207	release_sock(&smc->sk);
3208
3209	return put_user(answ, (int __user *)arg);
3210}
3211
3212/* Map the affected portions of the rmbe into an spd, note the number of bytes
3213 * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
3214 * updates till whenever a respective page has been fully processed.
3215 * Note that subsequent recv() calls have to wait till all splice() processing
3216 * completed.
3217 */
3218static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
3219			       struct pipe_inode_info *pipe, size_t len,
3220			       unsigned int flags)
3221{
3222	struct sock *sk = sock->sk;
3223	struct smc_sock *smc;
3224	int rc = -ENOTCONN;
3225
3226	smc = smc_sk(sk);
3227	lock_sock(sk);
3228	if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
3229		/* socket was connected before, no more data to read */
3230		rc = 0;
3231		goto out;
3232	}
3233	if (sk->sk_state == SMC_INIT ||
3234	    sk->sk_state == SMC_LISTEN ||
3235	    sk->sk_state == SMC_CLOSED)
3236		goto out;
3237
3238	if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
3239		rc = 0;
3240		goto out;
3241	}
3242
3243	if (smc->use_fallback) {
3244		rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
3245						    pipe, len, flags);
3246	} else {
3247		if (*ppos) {
3248			rc = -ESPIPE;
3249			goto out;
3250		}
3251		if (flags & SPLICE_F_NONBLOCK)
3252			flags = MSG_DONTWAIT;
3253		else
3254			flags = 0;
3255		SMC_STAT_INC(smc, splice_cnt);
3256		rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
3257	}
3258out:
3259	release_sock(sk);
3260
3261	return rc;
3262}
3263
3264/* must look like tcp */
3265static const struct proto_ops smc_sock_ops = {
3266	.family		= PF_SMC,
3267	.owner		= THIS_MODULE,
3268	.release	= smc_release,
3269	.bind		= smc_bind,
3270	.connect	= smc_connect,
3271	.socketpair	= sock_no_socketpair,
3272	.accept		= smc_accept,
3273	.getname	= smc_getname,
3274	.poll		= smc_poll,
3275	.ioctl		= smc_ioctl,
3276	.listen		= smc_listen,
3277	.shutdown	= smc_shutdown,
3278	.setsockopt	= smc_setsockopt,
3279	.getsockopt	= smc_getsockopt,
3280	.sendmsg	= smc_sendmsg,
3281	.recvmsg	= smc_recvmsg,
3282	.mmap		= sock_no_mmap,
3283	.splice_read	= smc_splice_read,
3284};
3285
3286static int __smc_create(struct net *net, struct socket *sock, int protocol,
3287			int kern, struct socket *clcsock)
3288{
3289	int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
3290	struct smc_sock *smc;
3291	struct sock *sk;
3292	int rc;
3293
3294	rc = -ESOCKTNOSUPPORT;
3295	if (sock->type != SOCK_STREAM)
3296		goto out;
3297
3298	rc = -EPROTONOSUPPORT;
3299	if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
3300		goto out;
3301
3302	rc = -ENOBUFS;
3303	sock->ops = &smc_sock_ops;
3304	sock->state = SS_UNCONNECTED;
3305	sk = smc_sock_alloc(net, sock, protocol);
3306	if (!sk)
3307		goto out;
3308
3309	/* create internal TCP socket for CLC handshake and fallback */
3310	smc = smc_sk(sk);
3311	smc->use_fallback = false; /* assume rdma capability first */
3312	smc->fallback_rsn = 0;
3313
3314	/* default behavior from limit_smc_hs in every net namespace */
3315	smc->limit_smc_hs = net->smc.limit_smc_hs;
3316
3317	rc = 0;
3318	if (!clcsock) {
3319		rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
3320				      &smc->clcsock);
3321		if (rc) {
3322			sk_common_release(sk);
3323			goto out;
3324		}
3325
3326		/* smc_clcsock_release() does not wait smc->clcsock->sk's
3327		 * destruction;  its sk_state might not be TCP_CLOSE after
3328		 * smc->sk is close()d, and TCP timers can be fired later,
3329		 * which need net ref.
3330		 */
3331		sk = smc->clcsock->sk;
3332		__netns_tracker_free(net, &sk->ns_tracker, false);
3333		sk->sk_net_refcnt = 1;
3334		get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
3335		sock_inuse_add(net, 1);
3336	} else {
3337		smc->clcsock = clcsock;
3338	}
3339
3340out:
3341	return rc;
3342}
3343
3344static int smc_create(struct net *net, struct socket *sock, int protocol,
3345		      int kern)
3346{
3347	return __smc_create(net, sock, protocol, kern, NULL);
3348}
3349
3350static const struct net_proto_family smc_sock_family_ops = {
3351	.family	= PF_SMC,
3352	.owner	= THIS_MODULE,
3353	.create	= smc_create,
3354};
3355
3356static int smc_ulp_init(struct sock *sk)
3357{
3358	struct socket *tcp = sk->sk_socket;
3359	struct net *net = sock_net(sk);
3360	struct socket *smcsock;
3361	int protocol, ret;
3362
3363	/* only TCP can be replaced */
3364	if (tcp->type != SOCK_STREAM || sk->sk_protocol != IPPROTO_TCP ||
3365	    (sk->sk_family != AF_INET && sk->sk_family != AF_INET6))
3366		return -ESOCKTNOSUPPORT;
3367	/* don't handle wq now */
3368	if (tcp->state != SS_UNCONNECTED || !tcp->file || tcp->wq.fasync_list)
3369		return -ENOTCONN;
3370
3371	if (sk->sk_family == AF_INET)
3372		protocol = SMCPROTO_SMC;
3373	else
3374		protocol = SMCPROTO_SMC6;
3375
3376	smcsock = sock_alloc();
3377	if (!smcsock)
3378		return -ENFILE;
3379
3380	smcsock->type = SOCK_STREAM;
3381	__module_get(THIS_MODULE); /* tried in __tcp_ulp_find_autoload */
3382	ret = __smc_create(net, smcsock, protocol, 1, tcp);
3383	if (ret) {
3384		sock_release(smcsock); /* module_put() which ops won't be NULL */
3385		return ret;
3386	}
3387
3388	/* replace tcp socket to smc */
3389	smcsock->file = tcp->file;
3390	smcsock->file->private_data = smcsock;
3391	smcsock->file->f_inode = SOCK_INODE(smcsock); /* replace inode when sock_close */
3392	smcsock->file->f_path.dentry->d_inode = SOCK_INODE(smcsock); /* dput() in __fput */
3393	tcp->file = NULL;
3394
3395	return ret;
3396}
3397
3398static void smc_ulp_clone(const struct request_sock *req, struct sock *newsk,
3399			  const gfp_t priority)
3400{
3401	struct inet_connection_sock *icsk = inet_csk(newsk);
3402
3403	/* don't inherit ulp ops to child when listen */
3404	icsk->icsk_ulp_ops = NULL;
3405}
3406
3407static struct tcp_ulp_ops smc_ulp_ops __read_mostly = {
3408	.name		= "smc",
3409	.owner		= THIS_MODULE,
3410	.init		= smc_ulp_init,
3411	.clone		= smc_ulp_clone,
3412};
3413
3414unsigned int smc_net_id;
3415
3416static __net_init int smc_net_init(struct net *net)
3417{
3418	int rc;
3419
3420	rc = smc_sysctl_net_init(net);
3421	if (rc)
3422		return rc;
3423	return smc_pnet_net_init(net);
3424}
3425
3426static void __net_exit smc_net_exit(struct net *net)
3427{
3428	smc_sysctl_net_exit(net);
3429	smc_pnet_net_exit(net);
3430}
3431
3432static __net_init int smc_net_stat_init(struct net *net)
3433{
3434	return smc_stats_init(net);
3435}
3436
3437static void __net_exit smc_net_stat_exit(struct net *net)
3438{
3439	smc_stats_exit(net);
3440}
3441
3442static struct pernet_operations smc_net_ops = {
3443	.init = smc_net_init,
3444	.exit = smc_net_exit,
3445	.id   = &smc_net_id,
3446	.size = sizeof(struct smc_net),
3447};
3448
3449static struct pernet_operations smc_net_stat_ops = {
3450	.init = smc_net_stat_init,
3451	.exit = smc_net_stat_exit,
3452};
3453
3454static int __init smc_init(void)
3455{
3456	int rc;
3457
3458	rc = register_pernet_subsys(&smc_net_ops);
3459	if (rc)
3460		return rc;
3461
3462	rc = register_pernet_subsys(&smc_net_stat_ops);
3463	if (rc)
3464		goto out_pernet_subsys;
3465
3466	rc = smc_ism_init();
3467	if (rc)
3468		goto out_pernet_subsys_stat;
3469	smc_clc_init();
3470
3471	rc = smc_nl_init();
3472	if (rc)
3473		goto out_ism;
3474
3475	rc = smc_pnet_init();
3476	if (rc)
3477		goto out_nl;
3478
3479	rc = -ENOMEM;
3480
3481	smc_tcp_ls_wq = alloc_workqueue("smc_tcp_ls_wq", 0, 0);
3482	if (!smc_tcp_ls_wq)
3483		goto out_pnet;
3484
3485	smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
3486	if (!smc_hs_wq)
3487		goto out_alloc_tcp_ls_wq;
3488
3489	smc_close_wq = alloc_workqueue("smc_close_wq", 0, 0);
3490	if (!smc_close_wq)
3491		goto out_alloc_hs_wq;
3492
3493	rc = smc_core_init();
3494	if (rc) {
3495		pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
3496		goto out_alloc_wqs;
3497	}
3498
3499	rc = smc_llc_init();
3500	if (rc) {
3501		pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
3502		goto out_core;
3503	}
3504
3505	rc = smc_cdc_init();
3506	if (rc) {
3507		pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
3508		goto out_core;
3509	}
3510
3511	rc = proto_register(&smc_proto, 1);
3512	if (rc) {
3513		pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
3514		goto out_core;
3515	}
3516
3517	rc = proto_register(&smc_proto6, 1);
3518	if (rc) {
3519		pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
3520		goto out_proto;
3521	}
3522
3523	rc = sock_register(&smc_sock_family_ops);
3524	if (rc) {
3525		pr_err("%s: sock_register fails with %d\n", __func__, rc);
3526		goto out_proto6;
3527	}
3528	INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
3529	INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
3530
3531	rc = smc_ib_register_client();
3532	if (rc) {
3533		pr_err("%s: ib_register fails with %d\n", __func__, rc);
3534		goto out_sock;
3535	}
3536
3537	rc = tcp_register_ulp(&smc_ulp_ops);
3538	if (rc) {
3539		pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3540		goto out_ib;
3541	}
3542
3543	static_branch_enable(&tcp_have_smc);
3544	return 0;
3545
3546out_ib:
3547	smc_ib_unregister_client();
3548out_sock:
3549	sock_unregister(PF_SMC);
3550out_proto6:
3551	proto_unregister(&smc_proto6);
3552out_proto:
3553	proto_unregister(&smc_proto);
3554out_core:
3555	smc_core_exit();
3556out_alloc_wqs:
3557	destroy_workqueue(smc_close_wq);
3558out_alloc_hs_wq:
3559	destroy_workqueue(smc_hs_wq);
3560out_alloc_tcp_ls_wq:
3561	destroy_workqueue(smc_tcp_ls_wq);
3562out_pnet:
3563	smc_pnet_exit();
3564out_nl:
3565	smc_nl_exit();
3566out_ism:
3567	smc_clc_exit();
3568	smc_ism_exit();
3569out_pernet_subsys_stat:
3570	unregister_pernet_subsys(&smc_net_stat_ops);
3571out_pernet_subsys:
3572	unregister_pernet_subsys(&smc_net_ops);
3573
3574	return rc;
3575}
3576
3577static void __exit smc_exit(void)
3578{
3579	static_branch_disable(&tcp_have_smc);
3580	tcp_unregister_ulp(&smc_ulp_ops);
3581	sock_unregister(PF_SMC);
3582	smc_core_exit();
3583	smc_ib_unregister_client();
3584	smc_ism_exit();
3585	destroy_workqueue(smc_close_wq);
3586	destroy_workqueue(smc_tcp_ls_wq);
3587	destroy_workqueue(smc_hs_wq);
3588	proto_unregister(&smc_proto6);
3589	proto_unregister(&smc_proto);
3590	smc_pnet_exit();
3591	smc_nl_exit();
3592	smc_clc_exit();
3593	unregister_pernet_subsys(&smc_net_stat_ops);
3594	unregister_pernet_subsys(&smc_net_ops);
3595	rcu_barrier();
3596}
3597
3598module_init(smc_init);
3599module_exit(smc_exit);
3600
3601MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
3602MODULE_DESCRIPTION("smc socket address family");
3603MODULE_LICENSE("GPL");
3604MODULE_ALIAS_NETPROTO(PF_SMC);
3605MODULE_ALIAS_TCP_ULP("smc");
3606MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);
3607