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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
30 #include <net/sock.h>
31 #include <net/tcp.h>
32 #include <net/smc.h>
33 #include <asm/ioctls.h>
34
35 #include <net/net_namespace.h>
36 #include <net/netns/generic.h>
37 #include "smc_netns.h"
38
39 #include "smc.h"
40 #include "smc_clc.h"
41 #include "smc_llc.h"
42 #include "smc_cdc.h"
43 #include "smc_core.h"
44 #include "smc_ib.h"
45 #include "smc_ism.h"
46 #include "smc_pnet.h"
47 #include "smc_tx.h"
48 #include "smc_rx.h"
49 #include "smc_close.h"
50
51 static DEFINE_MUTEX(smc_server_lgr_pending);    /* serialize link group
52                                                  * creation on server
53                                                  */
54 static DEFINE_MUTEX(smc_client_lgr_pending);    /* serialize link group
55                                                  * creation on client
56                                                  */
57
58 static void smc_tcp_listen_work(struct work_struct *);
59 static void smc_connect_work(struct work_struct *);
60
61 static void smc_set_keepalive(struct sock *sk, int val)
62 {
63         struct smc_sock *smc = smc_sk(sk);
64
65         smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
66 }
67
68 static struct smc_hashinfo smc_v4_hashinfo = {
69         .lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
70 };
71
72 static struct smc_hashinfo smc_v6_hashinfo = {
73         .lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
74 };
75
76 int smc_hash_sk(struct sock *sk)
77 {
78         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
79         struct hlist_head *head;
80
81         head = &h->ht;
82
83         write_lock_bh(&h->lock);
84         sk_add_node(sk, head);
85         sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
86         write_unlock_bh(&h->lock);
87
88         return 0;
89 }
90 EXPORT_SYMBOL_GPL(smc_hash_sk);
91
92 void smc_unhash_sk(struct sock *sk)
93 {
94         struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
95
96         write_lock_bh(&h->lock);
97         if (sk_del_node_init(sk))
98                 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
99         write_unlock_bh(&h->lock);
100 }
101 EXPORT_SYMBOL_GPL(smc_unhash_sk);
102
103 struct proto smc_proto = {
104         .name           = "SMC",
105         .owner          = THIS_MODULE,
106         .keepalive      = smc_set_keepalive,
107         .hash           = smc_hash_sk,
108         .unhash         = smc_unhash_sk,
109         .obj_size       = sizeof(struct smc_sock),
110         .h.smc_hash     = &smc_v4_hashinfo,
111         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
112 };
113 EXPORT_SYMBOL_GPL(smc_proto);
114
115 struct proto smc_proto6 = {
116         .name           = "SMC6",
117         .owner          = THIS_MODULE,
118         .keepalive      = smc_set_keepalive,
119         .hash           = smc_hash_sk,
120         .unhash         = smc_unhash_sk,
121         .obj_size       = sizeof(struct smc_sock),
122         .h.smc_hash     = &smc_v6_hashinfo,
123         .slab_flags     = SLAB_TYPESAFE_BY_RCU,
124 };
125 EXPORT_SYMBOL_GPL(smc_proto6);
126
127 static void smc_restore_fallback_changes(struct smc_sock *smc)
128 {
129         smc->clcsock->file->private_data = smc->sk.sk_socket;
130         smc->clcsock->file = NULL;
131 }
132
133 static int __smc_release(struct smc_sock *smc)
134 {
135         struct sock *sk = &smc->sk;
136         int rc = 0;
137
138         if (!smc->use_fallback) {
139                 rc = smc_close_active(smc);
140                 sock_set_flag(sk, SOCK_DEAD);
141                 sk->sk_shutdown |= SHUTDOWN_MASK;
142         } else {
143                 if (sk->sk_state != SMC_LISTEN && sk->sk_state != SMC_INIT)
144                         sock_put(sk); /* passive closing */
145                 if (sk->sk_state == SMC_LISTEN) {
146                         /* wake up clcsock accept */
147                         rc = kernel_sock_shutdown(smc->clcsock, SHUT_RDWR);
148                 }
149                 sk->sk_state = SMC_CLOSED;
150                 sk->sk_state_change(sk);
151                 smc_restore_fallback_changes(smc);
152         }
153
154         sk->sk_prot->unhash(sk);
155
156         if (sk->sk_state == SMC_CLOSED) {
157                 if (smc->clcsock) {
158                         release_sock(sk);
159                         smc_clcsock_release(smc);
160                         lock_sock(sk);
161                 }
162                 if (!smc->use_fallback)
163                         smc_conn_free(&smc->conn);
164         }
165
166         return rc;
167 }
168
169 static int smc_release(struct socket *sock)
170 {
171         struct sock *sk = sock->sk;
172         struct smc_sock *smc;
173         int rc = 0;
174
175         if (!sk)
176                 goto out;
177
178         sock_hold(sk); /* sock_put below */
179         smc = smc_sk(sk);
180
181         /* cleanup for a dangling non-blocking connect */
182         if (smc->connect_nonblock && sk->sk_state == SMC_INIT)
183                 tcp_abort(smc->clcsock->sk, ECONNABORTED);
184         flush_work(&smc->connect_work);
185
186         if (sk->sk_state == SMC_LISTEN)
187                 /* smc_close_non_accepted() is called and acquires
188                  * sock lock for child sockets again
189                  */
190                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
191         else
192                 lock_sock(sk);
193
194         rc = __smc_release(smc);
195
196         /* detach socket */
197         sock_orphan(sk);
198         sock->sk = NULL;
199         release_sock(sk);
200
201         sock_put(sk); /* sock_hold above */
202         sock_put(sk); /* final sock_put */
203 out:
204         return rc;
205 }
206
207 static void smc_destruct(struct sock *sk)
208 {
209         if (sk->sk_state != SMC_CLOSED)
210                 return;
211         if (!sock_flag(sk, SOCK_DEAD))
212                 return;
213
214         sk_refcnt_debug_dec(sk);
215 }
216
217 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
218                                    int protocol)
219 {
220         struct smc_sock *smc;
221         struct proto *prot;
222         struct sock *sk;
223
224         prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
225         sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
226         if (!sk)
227                 return NULL;
228
229         sock_init_data(sock, sk); /* sets sk_refcnt to 1 */
230         sk->sk_state = SMC_INIT;
231         sk->sk_destruct = smc_destruct;
232         sk->sk_protocol = protocol;
233         smc = smc_sk(sk);
234         INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work);
235         INIT_WORK(&smc->connect_work, smc_connect_work);
236         INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work);
237         INIT_LIST_HEAD(&smc->accept_q);
238         spin_lock_init(&smc->accept_q_lock);
239         spin_lock_init(&smc->conn.send_lock);
240         sk->sk_prot->hash(sk);
241         sk_refcnt_debug_inc(sk);
242         mutex_init(&smc->clcsock_release_lock);
243
244         return sk;
245 }
246
247 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
248                     int addr_len)
249 {
250         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
251         struct sock *sk = sock->sk;
252         struct smc_sock *smc;
253         int rc;
254
255         smc = smc_sk(sk);
256
257         /* replicate tests from inet_bind(), to be safe wrt. future changes */
258         rc = -EINVAL;
259         if (addr_len < sizeof(struct sockaddr_in))
260                 goto out;
261
262         rc = -EAFNOSUPPORT;
263         if (addr->sin_family != AF_INET &&
264             addr->sin_family != AF_INET6 &&
265             addr->sin_family != AF_UNSPEC)
266                 goto out;
267         /* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */
268         if (addr->sin_family == AF_UNSPEC &&
269             addr->sin_addr.s_addr != htonl(INADDR_ANY))
270                 goto out;
271
272         lock_sock(sk);
273
274         /* Check if socket is already active */
275         rc = -EINVAL;
276         if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
277                 goto out_rel;
278
279         smc->clcsock->sk->sk_reuse = sk->sk_reuse;
280         rc = kernel_bind(smc->clcsock, uaddr, addr_len);
281
282 out_rel:
283         release_sock(sk);
284 out:
285         return rc;
286 }
287
288 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
289                                    unsigned long mask)
290 {
291         /* options we don't get control via setsockopt for */
292         nsk->sk_type = osk->sk_type;
293         nsk->sk_sndbuf = osk->sk_sndbuf;
294         nsk->sk_rcvbuf = osk->sk_rcvbuf;
295         nsk->sk_sndtimeo = osk->sk_sndtimeo;
296         nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
297         nsk->sk_mark = osk->sk_mark;
298         nsk->sk_priority = osk->sk_priority;
299         nsk->sk_rcvlowat = osk->sk_rcvlowat;
300         nsk->sk_bound_dev_if = osk->sk_bound_dev_if;
301         nsk->sk_err = osk->sk_err;
302
303         nsk->sk_flags &= ~mask;
304         nsk->sk_flags |= osk->sk_flags & mask;
305 }
306
307 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
308                              (1UL << SOCK_KEEPOPEN) | \
309                              (1UL << SOCK_LINGER) | \
310                              (1UL << SOCK_BROADCAST) | \
311                              (1UL << SOCK_TIMESTAMP) | \
312                              (1UL << SOCK_DBG) | \
313                              (1UL << SOCK_RCVTSTAMP) | \
314                              (1UL << SOCK_RCVTSTAMPNS) | \
315                              (1UL << SOCK_LOCALROUTE) | \
316                              (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
317                              (1UL << SOCK_RXQ_OVFL) | \
318                              (1UL << SOCK_WIFI_STATUS) | \
319                              (1UL << SOCK_NOFCS) | \
320                              (1UL << SOCK_FILTER_LOCKED) | \
321                              (1UL << SOCK_TSTAMP_NEW))
322 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
323  * clc socket (since smc is not called for these options from net/core)
324  */
325 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
326 {
327         smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
328 }
329
330 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
331                              (1UL << SOCK_KEEPOPEN) | \
332                              (1UL << SOCK_LINGER) | \
333                              (1UL << SOCK_DBG))
334 /* copy only settings and flags relevant for smc from clc to smc socket */
335 static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
336 {
337         smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
338 }
339
340 /* register a new rmb, send confirm_rkey msg to register with peer */
341 static int smc_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc,
342                        bool conf_rkey)
343 {
344         if (!rmb_desc->wr_reg) {
345                 /* register memory region for new rmb */
346                 if (smc_wr_reg_send(link, rmb_desc->mr_rx[SMC_SINGLE_LINK])) {
347                         rmb_desc->regerr = 1;
348                         return -EFAULT;
349                 }
350                 rmb_desc->wr_reg = 1;
351         }
352         if (!conf_rkey)
353                 return 0;
354         /* exchange confirm_rkey msg with peer */
355         if (smc_llc_do_confirm_rkey(link, rmb_desc)) {
356                 rmb_desc->regerr = 1;
357                 return -EFAULT;
358         }
359         return 0;
360 }
361
362 static int smc_clnt_conf_first_link(struct smc_sock *smc)
363 {
364         struct net *net = sock_net(smc->clcsock->sk);
365         struct smc_link_group *lgr = smc->conn.lgr;
366         struct smc_link *link;
367         int rest;
368         int rc;
369
370         link = &lgr->lnk[SMC_SINGLE_LINK];
371         /* receive CONFIRM LINK request from server over RoCE fabric */
372         rest = wait_for_completion_interruptible_timeout(
373                 &link->llc_confirm,
374                 SMC_LLC_WAIT_FIRST_TIME);
375         if (rest <= 0) {
376                 struct smc_clc_msg_decline dclc;
377
378                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
379                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
380                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
381         }
382
383         if (link->llc_confirm_rc)
384                 return SMC_CLC_DECL_RMBE_EC;
385
386         rc = smc_ib_modify_qp_rts(link);
387         if (rc)
388                 return SMC_CLC_DECL_ERR_RDYLNK;
389
390         smc_wr_remember_qp_attr(link);
391
392         if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
393                 return SMC_CLC_DECL_ERR_REGRMB;
394
395         /* send CONFIRM LINK response over RoCE fabric */
396         rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
397         if (rc < 0)
398                 return SMC_CLC_DECL_TIMEOUT_CL;
399
400         /* receive ADD LINK request from server over RoCE fabric */
401         rest = wait_for_completion_interruptible_timeout(&link->llc_add,
402                                                          SMC_LLC_WAIT_TIME);
403         if (rest <= 0) {
404                 struct smc_clc_msg_decline dclc;
405
406                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
407                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
408                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_AL : rc;
409         }
410
411         /* send add link reject message, only one link supported for now */
412         rc = smc_llc_send_add_link(link,
413                                    link->smcibdev->mac[link->ibport - 1],
414                                    link->gid, SMC_LLC_RESP);
415         if (rc < 0)
416                 return SMC_CLC_DECL_TIMEOUT_AL;
417
418         smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
419
420         return 0;
421 }
422
423 static void smcr_conn_save_peer_info(struct smc_sock *smc,
424                                      struct smc_clc_msg_accept_confirm *clc)
425 {
426         int bufsize = smc_uncompress_bufsize(clc->rmbe_size);
427
428         smc->conn.peer_rmbe_idx = clc->rmbe_idx;
429         smc->conn.local_tx_ctrl.token = ntohl(clc->rmbe_alert_token);
430         smc->conn.peer_rmbe_size = bufsize;
431         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
432         smc->conn.tx_off = bufsize * (smc->conn.peer_rmbe_idx - 1);
433 }
434
435 static void smcd_conn_save_peer_info(struct smc_sock *smc,
436                                      struct smc_clc_msg_accept_confirm *clc)
437 {
438         int bufsize = smc_uncompress_bufsize(clc->dmbe_size);
439
440         smc->conn.peer_rmbe_idx = clc->dmbe_idx;
441         smc->conn.peer_token = clc->token;
442         /* msg header takes up space in the buffer */
443         smc->conn.peer_rmbe_size = bufsize - sizeof(struct smcd_cdc_msg);
444         atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size);
445         smc->conn.tx_off = bufsize * smc->conn.peer_rmbe_idx;
446 }
447
448 static void smc_conn_save_peer_info(struct smc_sock *smc,
449                                     struct smc_clc_msg_accept_confirm *clc)
450 {
451         if (smc->conn.lgr->is_smcd)
452                 smcd_conn_save_peer_info(smc, clc);
453         else
454                 smcr_conn_save_peer_info(smc, clc);
455 }
456
457 static void smc_link_save_peer_info(struct smc_link *link,
458                                     struct smc_clc_msg_accept_confirm *clc)
459 {
460         link->peer_qpn = ntoh24(clc->qpn);
461         memcpy(link->peer_gid, clc->lcl.gid, SMC_GID_SIZE);
462         memcpy(link->peer_mac, clc->lcl.mac, sizeof(link->peer_mac));
463         link->peer_psn = ntoh24(clc->psn);
464         link->peer_mtu = clc->qp_mtu;
465 }
466
467 static void smc_switch_to_fallback(struct smc_sock *smc)
468 {
469         smc->use_fallback = true;
470         if (smc->sk.sk_socket && smc->sk.sk_socket->file) {
471                 smc->clcsock->file = smc->sk.sk_socket->file;
472                 smc->clcsock->file->private_data = smc->clcsock;
473                 smc->clcsock->wq.fasync_list =
474                         smc->sk.sk_socket->wq.fasync_list;
475         }
476 }
477
478 /* fall back during connect */
479 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
480 {
481         smc_switch_to_fallback(smc);
482         smc->fallback_rsn = reason_code;
483         smc_copy_sock_settings_to_clc(smc);
484         smc->connect_nonblock = 0;
485         if (smc->sk.sk_state == SMC_INIT)
486                 smc->sk.sk_state = SMC_ACTIVE;
487         return 0;
488 }
489
490 /* decline and fall back during connect */
491 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code)
492 {
493         int rc;
494
495         if (reason_code < 0) { /* error, fallback is not possible */
496                 if (smc->sk.sk_state == SMC_INIT)
497                         sock_put(&smc->sk); /* passive closing */
498                 return reason_code;
499         }
500         if (reason_code != SMC_CLC_DECL_PEERDECL) {
501                 rc = smc_clc_send_decline(smc, reason_code);
502                 if (rc < 0) {
503                         if (smc->sk.sk_state == SMC_INIT)
504                                 sock_put(&smc->sk); /* passive closing */
505                         return rc;
506                 }
507         }
508         return smc_connect_fallback(smc, reason_code);
509 }
510
511 /* abort connecting */
512 static int smc_connect_abort(struct smc_sock *smc, int reason_code,
513                              int local_contact)
514 {
515         if (local_contact == SMC_FIRST_CONTACT)
516                 smc_lgr_forget(smc->conn.lgr);
517         if (smc->conn.lgr->is_smcd)
518                 /* there is only one lgr role for SMC-D; use server lock */
519                 mutex_unlock(&smc_server_lgr_pending);
520         else
521                 mutex_unlock(&smc_client_lgr_pending);
522
523         smc_conn_free(&smc->conn);
524         smc->connect_nonblock = 0;
525         return reason_code;
526 }
527
528 /* check if there is a rdma device available for this connection. */
529 /* called for connect and listen */
530 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
531 {
532         /* PNET table look up: search active ib_device and port
533          * within same PNETID that also contains the ethernet device
534          * used for the internal TCP socket
535          */
536         smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
537         if (!ini->ib_dev)
538                 return SMC_CLC_DECL_NOSMCRDEV;
539         return 0;
540 }
541
542 /* check if there is an ISM device available for this connection. */
543 /* called for connect and listen */
544 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
545 {
546         /* Find ISM device with same PNETID as connecting interface  */
547         smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
548         if (!ini->ism_dev)
549                 return SMC_CLC_DECL_NOSMCDDEV;
550         return 0;
551 }
552
553 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
554 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
555                                       struct smc_init_info *ini)
556 {
557         if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev, ini->vlan_id))
558                 return SMC_CLC_DECL_ISMVLANERR;
559         return 0;
560 }
561
562 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
563  * used, the VLAN ID will be registered again during the connection setup.
564  */
565 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc, bool is_smcd,
566                                         struct smc_init_info *ini)
567 {
568         if (!is_smcd)
569                 return 0;
570         if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev, ini->vlan_id))
571                 return SMC_CLC_DECL_CNFERR;
572         return 0;
573 }
574
575 /* CLC handshake during connect */
576 static int smc_connect_clc(struct smc_sock *smc, int smc_type,
577                            struct smc_clc_msg_accept_confirm *aclc,
578                            struct smc_init_info *ini)
579 {
580         int rc = 0;
581
582         /* do inband token exchange */
583         rc = smc_clc_send_proposal(smc, smc_type, ini);
584         if (rc)
585                 return rc;
586         /* receive SMC Accept CLC message */
587         return smc_clc_wait_msg(smc, aclc, sizeof(*aclc), SMC_CLC_ACCEPT,
588                                 CLC_WAIT_TIME);
589 }
590
591 /* setup for RDMA connection of client */
592 static int smc_connect_rdma(struct smc_sock *smc,
593                             struct smc_clc_msg_accept_confirm *aclc,
594                             struct smc_init_info *ini)
595 {
596         struct smc_link *link;
597         int reason_code = 0;
598
599         ini->is_smcd = false;
600         ini->ib_lcl = &aclc->lcl;
601         ini->ib_clcqpn = ntoh24(aclc->qpn);
602         ini->srv_first_contact = aclc->hdr.flag;
603
604         mutex_lock(&smc_client_lgr_pending);
605         reason_code = smc_conn_create(smc, ini);
606         if (reason_code) {
607                 mutex_unlock(&smc_client_lgr_pending);
608                 return reason_code;
609         }
610         link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK];
611
612         smc_conn_save_peer_info(smc, aclc);
613
614         /* create send buffer and rmb */
615         if (smc_buf_create(smc, false))
616                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM,
617                                          ini->cln_first_contact);
618
619         if (ini->cln_first_contact == SMC_FIRST_CONTACT)
620                 smc_link_save_peer_info(link, aclc);
621
622         if (smc_rmb_rtoken_handling(&smc->conn, aclc))
623                 return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RTOK,
624                                          ini->cln_first_contact);
625
626         smc_close_init(smc);
627         smc_rx_init(smc);
628
629         if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
630                 if (smc_ib_ready_link(link))
631                         return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RDYLNK,
632                                                  ini->cln_first_contact);
633         } else {
634                 if (smc_reg_rmb(link, smc->conn.rmb_desc, true))
635                         return smc_connect_abort(smc, SMC_CLC_DECL_ERR_REGRMB,
636                                                  ini->cln_first_contact);
637         }
638         smc_rmb_sync_sg_for_device(&smc->conn);
639
640         reason_code = smc_clc_send_confirm(smc);
641         if (reason_code)
642                 return smc_connect_abort(smc, reason_code,
643                                          ini->cln_first_contact);
644
645         smc_tx_init(smc);
646
647         if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
648                 /* QP confirmation over RoCE fabric */
649                 reason_code = smc_clnt_conf_first_link(smc);
650                 if (reason_code)
651                         return smc_connect_abort(smc, reason_code,
652                                                  ini->cln_first_contact);
653         }
654         mutex_unlock(&smc_client_lgr_pending);
655
656         smc_copy_sock_settings_to_clc(smc);
657         smc->connect_nonblock = 0;
658         if (smc->sk.sk_state == SMC_INIT)
659                 smc->sk.sk_state = SMC_ACTIVE;
660
661         return 0;
662 }
663
664 /* setup for ISM connection of client */
665 static int smc_connect_ism(struct smc_sock *smc,
666                            struct smc_clc_msg_accept_confirm *aclc,
667                            struct smc_init_info *ini)
668 {
669         int rc = 0;
670
671         ini->is_smcd = true;
672         ini->ism_gid = aclc->gid;
673         ini->srv_first_contact = aclc->hdr.flag;
674
675         /* there is only one lgr role for SMC-D; use server lock */
676         mutex_lock(&smc_server_lgr_pending);
677         rc = smc_conn_create(smc, ini);
678         if (rc) {
679                 mutex_unlock(&smc_server_lgr_pending);
680                 return rc;
681         }
682
683         /* Create send and receive buffers */
684         if (smc_buf_create(smc, true))
685                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM,
686                                          ini->cln_first_contact);
687
688         smc_conn_save_peer_info(smc, aclc);
689         smc_close_init(smc);
690         smc_rx_init(smc);
691         smc_tx_init(smc);
692
693         rc = smc_clc_send_confirm(smc);
694         if (rc)
695                 return smc_connect_abort(smc, rc, ini->cln_first_contact);
696         mutex_unlock(&smc_server_lgr_pending);
697
698         smc_copy_sock_settings_to_clc(smc);
699         smc->connect_nonblock = 0;
700         if (smc->sk.sk_state == SMC_INIT)
701                 smc->sk.sk_state = SMC_ACTIVE;
702
703         return 0;
704 }
705
706 /* perform steps before actually connecting */
707 static int __smc_connect(struct smc_sock *smc)
708 {
709         bool ism_supported = false, rdma_supported = false;
710         struct smc_clc_msg_accept_confirm aclc;
711         struct smc_init_info ini = {0};
712         int smc_type;
713         int rc = 0;
714
715         if (smc->use_fallback)
716                 return smc_connect_fallback(smc, smc->fallback_rsn);
717
718         /* if peer has not signalled SMC-capability, fall back */
719         if (!tcp_sk(smc->clcsock->sk)->syn_smc)
720                 return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
721
722         /* IPSec connections opt out of SMC-R optimizations */
723         if (using_ipsec(smc))
724                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC);
725
726         /* get vlan id from IP device */
727         if (smc_vlan_by_tcpsk(smc->clcsock, &ini))
728                 return smc_connect_decline_fallback(smc,
729                                                     SMC_CLC_DECL_GETVLANERR);
730
731         /* check if there is an ism device available */
732         if (!smc_find_ism_device(smc, &ini) &&
733             !smc_connect_ism_vlan_setup(smc, &ini)) {
734                 /* ISM is supported for this connection */
735                 ism_supported = true;
736                 smc_type = SMC_TYPE_D;
737         }
738
739         /* check if there is a rdma device available */
740         if (!smc_find_rdma_device(smc, &ini)) {
741                 /* RDMA is supported for this connection */
742                 rdma_supported = true;
743                 if (ism_supported)
744                         smc_type = SMC_TYPE_B; /* both */
745                 else
746                         smc_type = SMC_TYPE_R; /* only RDMA */
747         }
748
749         /* if neither ISM nor RDMA are supported, fallback */
750         if (!rdma_supported && !ism_supported)
751                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_NOSMCDEV);
752
753         /* perform CLC handshake */
754         rc = smc_connect_clc(smc, smc_type, &aclc, &ini);
755         if (rc) {
756                 smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
757                 return smc_connect_decline_fallback(smc, rc);
758         }
759
760         /* depending on previous steps, connect using rdma or ism */
761         if (rdma_supported && aclc.hdr.path == SMC_TYPE_R)
762                 rc = smc_connect_rdma(smc, &aclc, &ini);
763         else if (ism_supported && aclc.hdr.path == SMC_TYPE_D)
764                 rc = smc_connect_ism(smc, &aclc, &ini);
765         else
766                 rc = SMC_CLC_DECL_MODEUNSUPP;
767         if (rc) {
768                 smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
769                 return smc_connect_decline_fallback(smc, rc);
770         }
771
772         smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
773         return 0;
774 }
775
776 static void smc_connect_work(struct work_struct *work)
777 {
778         struct smc_sock *smc = container_of(work, struct smc_sock,
779                                             connect_work);
780         long timeo = smc->sk.sk_sndtimeo;
781         int rc = 0;
782
783         if (!timeo)
784                 timeo = MAX_SCHEDULE_TIMEOUT;
785         lock_sock(smc->clcsock->sk);
786         if (smc->clcsock->sk->sk_err) {
787                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
788         } else if ((1 << smc->clcsock->sk->sk_state) &
789                                         (TCPF_SYN_SENT | TCP_SYN_RECV)) {
790                 rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
791                 if ((rc == -EPIPE) &&
792                     ((1 << smc->clcsock->sk->sk_state) &
793                                         (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
794                         rc = 0;
795         }
796         release_sock(smc->clcsock->sk);
797         lock_sock(&smc->sk);
798         if (rc != 0 || smc->sk.sk_err) {
799                 smc->sk.sk_state = SMC_CLOSED;
800                 if (rc == -EPIPE || rc == -EAGAIN)
801                         smc->sk.sk_err = EPIPE;
802                 else if (signal_pending(current))
803                         smc->sk.sk_err = -sock_intr_errno(timeo);
804                 sock_put(&smc->sk); /* passive closing */
805                 goto out;
806         }
807
808         rc = __smc_connect(smc);
809         if (rc < 0)
810                 smc->sk.sk_err = -rc;
811
812 out:
813         if (!sock_flag(&smc->sk, SOCK_DEAD)) {
814                 if (smc->sk.sk_err) {
815                         smc->sk.sk_state_change(&smc->sk);
816                 } else { /* allow polling before and after fallback decision */
817                         smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
818                         smc->sk.sk_write_space(&smc->sk);
819                 }
820         }
821         release_sock(&smc->sk);
822 }
823
824 static int smc_connect(struct socket *sock, struct sockaddr *addr,
825                        int alen, int flags)
826 {
827         struct sock *sk = sock->sk;
828         struct smc_sock *smc;
829         int rc = -EINVAL;
830
831         smc = smc_sk(sk);
832
833         /* separate smc parameter checking to be safe */
834         if (alen < sizeof(addr->sa_family))
835                 goto out_err;
836         if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
837                 goto out_err;
838
839         lock_sock(sk);
840         switch (sk->sk_state) {
841         default:
842                 goto out;
843         case SMC_ACTIVE:
844                 rc = -EISCONN;
845                 goto out;
846         case SMC_INIT:
847                 rc = 0;
848                 break;
849         }
850
851         smc_copy_sock_settings_to_clc(smc);
852         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
853         if (smc->connect_nonblock) {
854                 rc = -EALREADY;
855                 goto out;
856         }
857         rc = kernel_connect(smc->clcsock, addr, alen, flags);
858         if (rc && rc != -EINPROGRESS)
859                 goto out;
860
861         sock_hold(&smc->sk); /* sock put in passive closing */
862         if (smc->use_fallback)
863                 goto out;
864         if (flags & O_NONBLOCK) {
865                 if (schedule_work(&smc->connect_work))
866                         smc->connect_nonblock = 1;
867                 rc = -EINPROGRESS;
868         } else {
869                 rc = __smc_connect(smc);
870                 if (rc < 0)
871                         goto out;
872                 else
873                         rc = 0; /* success cases including fallback */
874         }
875
876 out:
877         release_sock(sk);
878 out_err:
879         return rc;
880 }
881
882 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
883 {
884         struct socket *new_clcsock = NULL;
885         struct sock *lsk = &lsmc->sk;
886         struct sock *new_sk;
887         int rc = -EINVAL;
888
889         release_sock(lsk);
890         new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
891         if (!new_sk) {
892                 rc = -ENOMEM;
893                 lsk->sk_err = ENOMEM;
894                 *new_smc = NULL;
895                 lock_sock(lsk);
896                 goto out;
897         }
898         *new_smc = smc_sk(new_sk);
899
900         mutex_lock(&lsmc->clcsock_release_lock);
901         if (lsmc->clcsock)
902                 rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0);
903         mutex_unlock(&lsmc->clcsock_release_lock);
904         lock_sock(lsk);
905         if  (rc < 0)
906                 lsk->sk_err = -rc;
907         if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
908                 new_sk->sk_prot->unhash(new_sk);
909                 if (new_clcsock)
910                         sock_release(new_clcsock);
911                 new_sk->sk_state = SMC_CLOSED;
912                 sock_set_flag(new_sk, SOCK_DEAD);
913                 sock_put(new_sk); /* final */
914                 *new_smc = NULL;
915                 goto out;
916         }
917
918         (*new_smc)->clcsock = new_clcsock;
919 out:
920         return rc;
921 }
922
923 /* add a just created sock to the accept queue of the listen sock as
924  * candidate for a following socket accept call from user space
925  */
926 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
927 {
928         struct smc_sock *par = smc_sk(parent);
929
930         sock_hold(sk); /* sock_put in smc_accept_unlink () */
931         spin_lock(&par->accept_q_lock);
932         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
933         spin_unlock(&par->accept_q_lock);
934         sk_acceptq_added(parent);
935 }
936
937 /* remove a socket from the accept queue of its parental listening socket */
938 static void smc_accept_unlink(struct sock *sk)
939 {
940         struct smc_sock *par = smc_sk(sk)->listen_smc;
941
942         spin_lock(&par->accept_q_lock);
943         list_del_init(&smc_sk(sk)->accept_q);
944         spin_unlock(&par->accept_q_lock);
945         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
946         sock_put(sk); /* sock_hold in smc_accept_enqueue */
947 }
948
949 /* remove a sock from the accept queue to bind it to a new socket created
950  * for a socket accept call from user space
951  */
952 struct sock *smc_accept_dequeue(struct sock *parent,
953                                 struct socket *new_sock)
954 {
955         struct smc_sock *isk, *n;
956         struct sock *new_sk;
957
958         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
959                 new_sk = (struct sock *)isk;
960
961                 smc_accept_unlink(new_sk);
962                 if (new_sk->sk_state == SMC_CLOSED) {
963                         new_sk->sk_prot->unhash(new_sk);
964                         if (isk->clcsock) {
965                                 sock_release(isk->clcsock);
966                                 isk->clcsock = NULL;
967                         }
968                         sock_put(new_sk); /* final */
969                         continue;
970                 }
971                 if (new_sock) {
972                         sock_graft(new_sk, new_sock);
973                         if (isk->use_fallback) {
974                                 smc_sk(new_sk)->clcsock->file = new_sock->file;
975                                 isk->clcsock->file->private_data = isk->clcsock;
976                         }
977                 }
978                 return new_sk;
979         }
980         return NULL;
981 }
982
983 /* clean up for a created but never accepted sock */
984 void smc_close_non_accepted(struct sock *sk)
985 {
986         struct smc_sock *smc = smc_sk(sk);
987
988         sock_hold(sk); /* sock_put below */
989         lock_sock(sk);
990         if (!sk->sk_lingertime)
991                 /* wait for peer closing */
992                 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
993         __smc_release(smc);
994         release_sock(sk);
995         sock_put(sk); /* sock_hold above */
996         sock_put(sk); /* final sock_put */
997 }
998
999 static int smc_serv_conf_first_link(struct smc_sock *smc)
1000 {
1001         struct net *net = sock_net(smc->clcsock->sk);
1002         struct smc_link_group *lgr = smc->conn.lgr;
1003         struct smc_link *link;
1004         int rest;
1005         int rc;
1006
1007         link = &lgr->lnk[SMC_SINGLE_LINK];
1008
1009         if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
1010                 return SMC_CLC_DECL_ERR_REGRMB;
1011
1012         /* send CONFIRM LINK request to client over the RoCE fabric */
1013         rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1014         if (rc < 0)
1015                 return SMC_CLC_DECL_TIMEOUT_CL;
1016
1017         /* receive CONFIRM LINK response from client over the RoCE fabric */
1018         rest = wait_for_completion_interruptible_timeout(
1019                 &link->llc_confirm_resp,
1020                 SMC_LLC_WAIT_FIRST_TIME);
1021         if (rest <= 0) {
1022                 struct smc_clc_msg_decline dclc;
1023
1024                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1025                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1026                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1027         }
1028
1029         if (link->llc_confirm_resp_rc)
1030                 return SMC_CLC_DECL_RMBE_EC;
1031
1032         /* send ADD LINK request to client over the RoCE fabric */
1033         rc = smc_llc_send_add_link(link,
1034                                    link->smcibdev->mac[link->ibport - 1],
1035                                    link->gid, SMC_LLC_REQ);
1036         if (rc < 0)
1037                 return SMC_CLC_DECL_TIMEOUT_AL;
1038
1039         /* receive ADD LINK response from client over the RoCE fabric */
1040         rest = wait_for_completion_interruptible_timeout(&link->llc_add_resp,
1041                                                          SMC_LLC_WAIT_TIME);
1042         if (rest <= 0) {
1043                 struct smc_clc_msg_decline dclc;
1044
1045                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1046                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1047                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_AL : rc;
1048         }
1049
1050         smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
1051
1052         return 0;
1053 }
1054
1055 /* listen worker: finish */
1056 static void smc_listen_out(struct smc_sock *new_smc)
1057 {
1058         struct smc_sock *lsmc = new_smc->listen_smc;
1059         struct sock *newsmcsk = &new_smc->sk;
1060
1061         if (lsmc->sk.sk_state == SMC_LISTEN) {
1062                 lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1063                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
1064                 release_sock(&lsmc->sk);
1065         } else { /* no longer listening */
1066                 smc_close_non_accepted(newsmcsk);
1067         }
1068
1069         /* Wake up accept */
1070         lsmc->sk.sk_data_ready(&lsmc->sk);
1071         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1072 }
1073
1074 /* listen worker: finish in state connected */
1075 static void smc_listen_out_connected(struct smc_sock *new_smc)
1076 {
1077         struct sock *newsmcsk = &new_smc->sk;
1078
1079         sk_refcnt_debug_inc(newsmcsk);
1080         if (newsmcsk->sk_state == SMC_INIT)
1081                 newsmcsk->sk_state = SMC_ACTIVE;
1082
1083         smc_listen_out(new_smc);
1084 }
1085
1086 /* listen worker: finish in error state */
1087 static void smc_listen_out_err(struct smc_sock *new_smc)
1088 {
1089         struct sock *newsmcsk = &new_smc->sk;
1090
1091         if (newsmcsk->sk_state == SMC_INIT)
1092                 sock_put(&new_smc->sk); /* passive closing */
1093         newsmcsk->sk_state = SMC_CLOSED;
1094         smc_conn_free(&new_smc->conn);
1095
1096         smc_listen_out(new_smc);
1097 }
1098
1099 /* listen worker: decline and fall back if possible */
1100 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1101                                int local_contact)
1102 {
1103         /* RDMA setup failed, switch back to TCP */
1104         if (local_contact == SMC_FIRST_CONTACT)
1105                 smc_lgr_forget(new_smc->conn.lgr);
1106         if (reason_code < 0) { /* error, no fallback possible */
1107                 smc_listen_out_err(new_smc);
1108                 return;
1109         }
1110         smc_conn_free(&new_smc->conn);
1111         smc_switch_to_fallback(new_smc);
1112         new_smc->fallback_rsn = reason_code;
1113         if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1114                 if (smc_clc_send_decline(new_smc, reason_code) < 0) {
1115                         smc_listen_out_err(new_smc);
1116                         return;
1117                 }
1118         }
1119         smc_listen_out_connected(new_smc);
1120 }
1121
1122 /* listen worker: check prefixes */
1123 static int smc_listen_prfx_check(struct smc_sock *new_smc,
1124                                  struct smc_clc_msg_proposal *pclc)
1125 {
1126         struct smc_clc_msg_proposal_prefix *pclc_prfx;
1127         struct socket *newclcsock = new_smc->clcsock;
1128
1129         pclc_prfx = smc_clc_proposal_get_prefix(pclc);
1130         if (smc_clc_prfx_match(newclcsock, pclc_prfx))
1131                 return SMC_CLC_DECL_DIFFPREFIX;
1132
1133         return 0;
1134 }
1135
1136 /* listen worker: initialize connection and buffers */
1137 static int smc_listen_rdma_init(struct smc_sock *new_smc,
1138                                 struct smc_init_info *ini)
1139 {
1140         int rc;
1141
1142         /* allocate connection / link group */
1143         rc = smc_conn_create(new_smc, ini);
1144         if (rc)
1145                 return rc;
1146
1147         /* create send buffer and rmb */
1148         if (smc_buf_create(new_smc, false))
1149                 return SMC_CLC_DECL_MEM;
1150
1151         return 0;
1152 }
1153
1154 /* listen worker: initialize connection and buffers for SMC-D */
1155 static int smc_listen_ism_init(struct smc_sock *new_smc,
1156                                struct smc_clc_msg_proposal *pclc,
1157                                struct smc_init_info *ini)
1158 {
1159         struct smc_clc_msg_smcd *pclc_smcd;
1160         int rc;
1161
1162         pclc_smcd = smc_get_clc_msg_smcd(pclc);
1163         ini->ism_gid = pclc_smcd->gid;
1164         rc = smc_conn_create(new_smc, ini);
1165         if (rc)
1166                 return rc;
1167
1168         /* Check if peer can be reached via ISM device */
1169         if (smc_ism_cantalk(new_smc->conn.lgr->peer_gid,
1170                             new_smc->conn.lgr->vlan_id,
1171                             new_smc->conn.lgr->smcd)) {
1172                 if (ini->cln_first_contact == SMC_FIRST_CONTACT)
1173                         smc_lgr_forget(new_smc->conn.lgr);
1174                 smc_conn_free(&new_smc->conn);
1175                 return SMC_CLC_DECL_SMCDNOTALK;
1176         }
1177
1178         /* Create send and receive buffers */
1179         if (smc_buf_create(new_smc, true)) {
1180                 if (ini->cln_first_contact == SMC_FIRST_CONTACT)
1181                         smc_lgr_forget(new_smc->conn.lgr);
1182                 smc_conn_free(&new_smc->conn);
1183                 return SMC_CLC_DECL_MEM;
1184         }
1185
1186         return 0;
1187 }
1188
1189 /* listen worker: register buffers */
1190 static int smc_listen_rdma_reg(struct smc_sock *new_smc, int local_contact)
1191 {
1192         struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1193
1194         if (local_contact != SMC_FIRST_CONTACT) {
1195                 if (smc_reg_rmb(link, new_smc->conn.rmb_desc, true))
1196                         return SMC_CLC_DECL_ERR_REGRMB;
1197         }
1198         smc_rmb_sync_sg_for_device(&new_smc->conn);
1199
1200         return 0;
1201 }
1202
1203 /* listen worker: finish RDMA setup */
1204 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
1205                                   struct smc_clc_msg_accept_confirm *cclc,
1206                                   int local_contact)
1207 {
1208         struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1209         int reason_code = 0;
1210
1211         if (local_contact == SMC_FIRST_CONTACT)
1212                 smc_link_save_peer_info(link, cclc);
1213
1214         if (smc_rmb_rtoken_handling(&new_smc->conn, cclc)) {
1215                 reason_code = SMC_CLC_DECL_ERR_RTOK;
1216                 goto decline;
1217         }
1218
1219         if (local_contact == SMC_FIRST_CONTACT) {
1220                 if (smc_ib_ready_link(link)) {
1221                         reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1222                         goto decline;
1223                 }
1224                 /* QP confirmation over RoCE fabric */
1225                 reason_code = smc_serv_conf_first_link(new_smc);
1226                 if (reason_code)
1227                         goto decline;
1228         }
1229         return 0;
1230
1231 decline:
1232         smc_listen_decline(new_smc, reason_code, local_contact);
1233         return reason_code;
1234 }
1235
1236 /* setup for RDMA connection of server */
1237 static void smc_listen_work(struct work_struct *work)
1238 {
1239         struct smc_sock *new_smc = container_of(work, struct smc_sock,
1240                                                 smc_listen_work);
1241         struct socket *newclcsock = new_smc->clcsock;
1242         struct smc_clc_msg_accept_confirm cclc;
1243         struct smc_clc_msg_proposal *pclc;
1244         struct smc_init_info ini = {0};
1245         bool ism_supported = false;
1246         u8 buf[SMC_CLC_MAX_LEN];
1247         int rc = 0;
1248
1249         if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
1250                 return smc_listen_out_err(new_smc);
1251
1252         if (new_smc->use_fallback) {
1253                 smc_listen_out_connected(new_smc);
1254                 return;
1255         }
1256
1257         /* check if peer is smc capable */
1258         if (!tcp_sk(newclcsock->sk)->syn_smc) {
1259                 smc_switch_to_fallback(new_smc);
1260                 new_smc->fallback_rsn = SMC_CLC_DECL_PEERNOSMC;
1261                 smc_listen_out_connected(new_smc);
1262                 return;
1263         }
1264
1265         /* do inband token exchange -
1266          * wait for and receive SMC Proposal CLC message
1267          */
1268         pclc = (struct smc_clc_msg_proposal *)&buf;
1269         rc = smc_clc_wait_msg(new_smc, pclc, SMC_CLC_MAX_LEN,
1270                               SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
1271         if (rc)
1272                 goto out_decl;
1273
1274         /* IPSec connections opt out of SMC-R optimizations */
1275         if (using_ipsec(new_smc)) {
1276                 rc = SMC_CLC_DECL_IPSEC;
1277                 goto out_decl;
1278         }
1279
1280         /* check for matching IP prefix and subnet length */
1281         rc = smc_listen_prfx_check(new_smc, pclc);
1282         if (rc)
1283                 goto out_decl;
1284
1285         /* get vlan id from IP device */
1286         if (smc_vlan_by_tcpsk(new_smc->clcsock, &ini)) {
1287                 rc = SMC_CLC_DECL_GETVLANERR;
1288                 goto out_decl;
1289         }
1290
1291         mutex_lock(&smc_server_lgr_pending);
1292         smc_close_init(new_smc);
1293         smc_rx_init(new_smc);
1294         smc_tx_init(new_smc);
1295
1296         /* check if ISM is available */
1297         if (pclc->hdr.path == SMC_TYPE_D || pclc->hdr.path == SMC_TYPE_B) {
1298                 ini.is_smcd = true; /* prepare ISM check */
1299                 rc = smc_find_ism_device(new_smc, &ini);
1300                 if (!rc)
1301                         rc = smc_listen_ism_init(new_smc, pclc, &ini);
1302                 if (!rc)
1303                         ism_supported = true;
1304                 else if (pclc->hdr.path == SMC_TYPE_D)
1305                         goto out_unlock; /* skip RDMA and decline */
1306         }
1307
1308         /* check if RDMA is available */
1309         if (!ism_supported) { /* SMC_TYPE_R or SMC_TYPE_B */
1310                 /* prepare RDMA check */
1311                 ini.is_smcd = false;
1312                 ini.ism_dev = NULL;
1313                 ini.ib_lcl = &pclc->lcl;
1314                 rc = smc_find_rdma_device(new_smc, &ini);
1315                 if (rc) {
1316                         /* no RDMA device found */
1317                         if (pclc->hdr.path == SMC_TYPE_B)
1318                                 /* neither ISM nor RDMA device found */
1319                                 rc = SMC_CLC_DECL_NOSMCDEV;
1320                         goto out_unlock;
1321                 }
1322                 rc = smc_listen_rdma_init(new_smc, &ini);
1323                 if (rc)
1324                         goto out_unlock;
1325                 rc = smc_listen_rdma_reg(new_smc, ini.cln_first_contact);
1326                 if (rc)
1327                         goto out_unlock;
1328         }
1329
1330         /* send SMC Accept CLC message */
1331         rc = smc_clc_send_accept(new_smc, ini.cln_first_contact);
1332         if (rc)
1333                 goto out_unlock;
1334
1335         /* SMC-D does not need this lock any more */
1336         if (ism_supported)
1337                 mutex_unlock(&smc_server_lgr_pending);
1338
1339         /* receive SMC Confirm CLC message */
1340         rc = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
1341                               SMC_CLC_CONFIRM, CLC_WAIT_TIME);
1342         if (rc) {
1343                 if (!ism_supported)
1344                         goto out_unlock;
1345                 goto out_decl;
1346         }
1347
1348         /* finish worker */
1349         if (!ism_supported) {
1350                 rc = smc_listen_rdma_finish(new_smc, &cclc,
1351                                             ini.cln_first_contact);
1352                 mutex_unlock(&smc_server_lgr_pending);
1353                 if (rc)
1354                         return;
1355         }
1356         smc_conn_save_peer_info(new_smc, &cclc);
1357         smc_listen_out_connected(new_smc);
1358         return;
1359
1360 out_unlock:
1361         mutex_unlock(&smc_server_lgr_pending);
1362 out_decl:
1363         smc_listen_decline(new_smc, rc, ini.cln_first_contact);
1364 }
1365
1366 static void smc_tcp_listen_work(struct work_struct *work)
1367 {
1368         struct smc_sock *lsmc = container_of(work, struct smc_sock,
1369                                              tcp_listen_work);
1370         struct sock *lsk = &lsmc->sk;
1371         struct smc_sock *new_smc;
1372         int rc = 0;
1373
1374         lock_sock(lsk);
1375         while (lsk->sk_state == SMC_LISTEN) {
1376                 rc = smc_clcsock_accept(lsmc, &new_smc);
1377                 if (rc)
1378                         goto out;
1379                 if (!new_smc)
1380                         continue;
1381
1382                 new_smc->listen_smc = lsmc;
1383                 new_smc->use_fallback = lsmc->use_fallback;
1384                 new_smc->fallback_rsn = lsmc->fallback_rsn;
1385                 sock_hold(lsk); /* sock_put in smc_listen_work */
1386                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
1387                 smc_copy_sock_settings_to_smc(new_smc);
1388                 new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
1389                 new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
1390                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
1391                 if (!schedule_work(&new_smc->smc_listen_work))
1392                         sock_put(&new_smc->sk);
1393         }
1394
1395 out:
1396         release_sock(lsk);
1397         sock_put(&lsmc->sk); /* sock_hold in smc_listen */
1398 }
1399
1400 static int smc_listen(struct socket *sock, int backlog)
1401 {
1402         struct sock *sk = sock->sk;
1403         struct smc_sock *smc;
1404         int rc;
1405
1406         smc = smc_sk(sk);
1407         lock_sock(sk);
1408
1409         rc = -EINVAL;
1410         if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
1411             smc->connect_nonblock)
1412                 goto out;
1413
1414         rc = 0;
1415         if (sk->sk_state == SMC_LISTEN) {
1416                 sk->sk_max_ack_backlog = backlog;
1417                 goto out;
1418         }
1419         /* some socket options are handled in core, so we could not apply
1420          * them to the clc socket -- copy smc socket options to clc socket
1421          */
1422         smc_copy_sock_settings_to_clc(smc);
1423         if (!smc->use_fallback)
1424                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1425
1426         rc = kernel_listen(smc->clcsock, backlog);
1427         if (rc)
1428                 goto out;
1429         sk->sk_max_ack_backlog = backlog;
1430         sk->sk_ack_backlog = 0;
1431         sk->sk_state = SMC_LISTEN;
1432         sock_hold(sk); /* sock_hold in tcp_listen_worker */
1433         if (!schedule_work(&smc->tcp_listen_work))
1434                 sock_put(sk);
1435
1436 out:
1437         release_sock(sk);
1438         return rc;
1439 }
1440
1441 static int smc_accept(struct socket *sock, struct socket *new_sock,
1442                       int flags, bool kern)
1443 {
1444         struct sock *sk = sock->sk, *nsk;
1445         DECLARE_WAITQUEUE(wait, current);
1446         struct smc_sock *lsmc;
1447         long timeo;
1448         int rc = 0;
1449
1450         lsmc = smc_sk(sk);
1451         sock_hold(sk); /* sock_put below */
1452         lock_sock(sk);
1453
1454         if (lsmc->sk.sk_state != SMC_LISTEN) {
1455                 rc = -EINVAL;
1456                 release_sock(sk);
1457                 goto out;
1458         }
1459
1460         /* Wait for an incoming connection */
1461         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
1462         add_wait_queue_exclusive(sk_sleep(sk), &wait);
1463         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
1464                 set_current_state(TASK_INTERRUPTIBLE);
1465                 if (!timeo) {
1466                         rc = -EAGAIN;
1467                         break;
1468                 }
1469                 release_sock(sk);
1470                 timeo = schedule_timeout(timeo);
1471                 /* wakeup by sk_data_ready in smc_listen_work() */
1472                 sched_annotate_sleep();
1473                 lock_sock(sk);
1474                 if (signal_pending(current)) {
1475                         rc = sock_intr_errno(timeo);
1476                         break;
1477                 }
1478         }
1479         set_current_state(TASK_RUNNING);
1480         remove_wait_queue(sk_sleep(sk), &wait);
1481
1482         if (!rc)
1483                 rc = sock_error(nsk);
1484         release_sock(sk);
1485         if (rc)
1486                 goto out;
1487
1488         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
1489                 /* wait till data arrives on the socket */
1490                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
1491                                                                 MSEC_PER_SEC);
1492                 if (smc_sk(nsk)->use_fallback) {
1493                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
1494
1495                         lock_sock(clcsk);
1496                         if (skb_queue_empty(&clcsk->sk_receive_queue))
1497                                 sk_wait_data(clcsk, &timeo, NULL);
1498                         release_sock(clcsk);
1499                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
1500                         lock_sock(nsk);
1501                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
1502                         release_sock(nsk);
1503                 }
1504         }
1505
1506 out:
1507         sock_put(sk); /* sock_hold above */
1508         return rc;
1509 }
1510
1511 static int smc_getname(struct socket *sock, struct sockaddr *addr,
1512                        int peer)
1513 {
1514         struct smc_sock *smc;
1515
1516         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
1517             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
1518                 return -ENOTCONN;
1519
1520         smc = smc_sk(sock->sk);
1521
1522         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
1523 }
1524
1525 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1526 {
1527         struct sock *sk = sock->sk;
1528         struct smc_sock *smc;
1529         int rc = -EPIPE;
1530
1531         smc = smc_sk(sk);
1532         lock_sock(sk);
1533         if ((sk->sk_state != SMC_ACTIVE) &&
1534             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1535             (sk->sk_state != SMC_INIT))
1536                 goto out;
1537
1538         if (msg->msg_flags & MSG_FASTOPEN) {
1539                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
1540                         smc_switch_to_fallback(smc);
1541                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
1542                 } else {
1543                         rc = -EINVAL;
1544                         goto out;
1545                 }
1546         }
1547
1548         if (smc->use_fallback)
1549                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
1550         else
1551                 rc = smc_tx_sendmsg(smc, msg, len);
1552 out:
1553         release_sock(sk);
1554         return rc;
1555 }
1556
1557 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1558                        int flags)
1559 {
1560         struct sock *sk = sock->sk;
1561         struct smc_sock *smc;
1562         int rc = -ENOTCONN;
1563
1564         smc = smc_sk(sk);
1565         lock_sock(sk);
1566         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
1567                 /* socket was connected before, no more data to read */
1568                 rc = 0;
1569                 goto out;
1570         }
1571         if ((sk->sk_state == SMC_INIT) ||
1572             (sk->sk_state == SMC_LISTEN) ||
1573             (sk->sk_state == SMC_CLOSED))
1574                 goto out;
1575
1576         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1577                 rc = 0;
1578                 goto out;
1579         }
1580
1581         if (smc->use_fallback) {
1582                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
1583         } else {
1584                 msg->msg_namelen = 0;
1585                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
1586         }
1587
1588 out:
1589         release_sock(sk);
1590         return rc;
1591 }
1592
1593 static __poll_t smc_accept_poll(struct sock *parent)
1594 {
1595         struct smc_sock *isk = smc_sk(parent);
1596         __poll_t mask = 0;
1597
1598         spin_lock(&isk->accept_q_lock);
1599         if (!list_empty(&isk->accept_q))
1600                 mask = EPOLLIN | EPOLLRDNORM;
1601         spin_unlock(&isk->accept_q_lock);
1602
1603         return mask;
1604 }
1605
1606 static __poll_t smc_poll(struct file *file, struct socket *sock,
1607                              poll_table *wait)
1608 {
1609         struct sock *sk = sock->sk;
1610         struct smc_sock *smc;
1611         __poll_t mask = 0;
1612
1613         if (!sk)
1614                 return EPOLLNVAL;
1615
1616         smc = smc_sk(sock->sk);
1617         if (smc->use_fallback) {
1618                 /* delegate to CLC child sock */
1619                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
1620                 sk->sk_err = smc->clcsock->sk->sk_err;
1621         } else {
1622                 if (sk->sk_state != SMC_CLOSED)
1623                         sock_poll_wait(file, sock, wait);
1624                 if (sk->sk_err)
1625                         mask |= EPOLLERR;
1626                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
1627                     (sk->sk_state == SMC_CLOSED))
1628                         mask |= EPOLLHUP;
1629                 if (sk->sk_state == SMC_LISTEN) {
1630                         /* woken up by sk_data_ready in smc_listen_work() */
1631                         mask |= smc_accept_poll(sk);
1632                 } else if (smc->use_fallback) { /* as result of connect_work()*/
1633                         mask |= smc->clcsock->ops->poll(file, smc->clcsock,
1634                                                            wait);
1635                         sk->sk_err = smc->clcsock->sk->sk_err;
1636                 } else {
1637                         if ((sk->sk_state != SMC_INIT &&
1638                              atomic_read(&smc->conn.sndbuf_space)) ||
1639                             sk->sk_shutdown & SEND_SHUTDOWN) {
1640                                 mask |= EPOLLOUT | EPOLLWRNORM;
1641                         } else {
1642                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1643                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1644                         }
1645                         if (atomic_read(&smc->conn.bytes_to_rcv))
1646                                 mask |= EPOLLIN | EPOLLRDNORM;
1647                         if (sk->sk_shutdown & RCV_SHUTDOWN)
1648                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
1649                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
1650                                 mask |= EPOLLIN;
1651                         if (smc->conn.urg_state == SMC_URG_VALID)
1652                                 mask |= EPOLLPRI;
1653                 }
1654         }
1655
1656         return mask;
1657 }
1658
1659 static int smc_shutdown(struct socket *sock, int how)
1660 {
1661         struct sock *sk = sock->sk;
1662         struct smc_sock *smc;
1663         int rc = -EINVAL;
1664         int rc1 = 0;
1665
1666         smc = smc_sk(sk);
1667
1668         if ((how < SHUT_RD) || (how > SHUT_RDWR))
1669                 return rc;
1670
1671         lock_sock(sk);
1672
1673         rc = -ENOTCONN;
1674         if ((sk->sk_state != SMC_ACTIVE) &&
1675             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
1676             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
1677             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1678             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
1679             (sk->sk_state != SMC_APPFINCLOSEWAIT))
1680                 goto out;
1681         if (smc->use_fallback) {
1682                 rc = kernel_sock_shutdown(smc->clcsock, how);
1683                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
1684                 if (sk->sk_shutdown == SHUTDOWN_MASK)
1685                         sk->sk_state = SMC_CLOSED;
1686                 goto out;
1687         }
1688         switch (how) {
1689         case SHUT_RDWR:         /* shutdown in both directions */
1690                 rc = smc_close_active(smc);
1691                 break;
1692         case SHUT_WR:
1693                 rc = smc_close_shutdown_write(smc);
1694                 break;
1695         case SHUT_RD:
1696                 rc = 0;
1697                 /* nothing more to do because peer is not involved */
1698                 break;
1699         }
1700         if (smc->clcsock)
1701                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
1702         /* map sock_shutdown_cmd constants to sk_shutdown value range */
1703         sk->sk_shutdown |= how + 1;
1704
1705 out:
1706         release_sock(sk);
1707         return rc ? rc : rc1;
1708 }
1709
1710 static int smc_setsockopt(struct socket *sock, int level, int optname,
1711                           char __user *optval, unsigned int optlen)
1712 {
1713         struct sock *sk = sock->sk;
1714         struct smc_sock *smc;
1715         int val, rc;
1716
1717         smc = smc_sk(sk);
1718
1719         /* generic setsockopts reaching us here always apply to the
1720          * CLC socket
1721          */
1722         rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
1723                                            optval, optlen);
1724         if (smc->clcsock->sk->sk_err) {
1725                 sk->sk_err = smc->clcsock->sk->sk_err;
1726                 sk->sk_error_report(sk);
1727         }
1728
1729         if (optlen < sizeof(int))
1730                 return -EINVAL;
1731         if (get_user(val, (int __user *)optval))
1732                 return -EFAULT;
1733
1734         lock_sock(sk);
1735         if (rc || smc->use_fallback)
1736                 goto out;
1737         switch (optname) {
1738         case TCP_ULP:
1739         case TCP_FASTOPEN:
1740         case TCP_FASTOPEN_CONNECT:
1741         case TCP_FASTOPEN_KEY:
1742         case TCP_FASTOPEN_NO_COOKIE:
1743                 /* option not supported by SMC */
1744                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
1745                         smc_switch_to_fallback(smc);
1746                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
1747                 } else {
1748                         rc = -EINVAL;
1749                 }
1750                 break;
1751         case TCP_NODELAY:
1752                 if (sk->sk_state != SMC_INIT &&
1753                     sk->sk_state != SMC_LISTEN &&
1754                     sk->sk_state != SMC_CLOSED) {
1755                         if (val)
1756                                 mod_delayed_work(system_wq, &smc->conn.tx_work,
1757                                                  0);
1758                 }
1759                 break;
1760         case TCP_CORK:
1761                 if (sk->sk_state != SMC_INIT &&
1762                     sk->sk_state != SMC_LISTEN &&
1763                     sk->sk_state != SMC_CLOSED) {
1764                         if (!val)
1765                                 mod_delayed_work(system_wq, &smc->conn.tx_work,
1766                                                  0);
1767                 }
1768                 break;
1769         case TCP_DEFER_ACCEPT:
1770                 smc->sockopt_defer_accept = val;
1771                 break;
1772         default:
1773                 break;
1774         }
1775 out:
1776         release_sock(sk);
1777
1778         return rc;
1779 }
1780
1781 static int smc_getsockopt(struct socket *sock, int level, int optname,
1782                           char __user *optval, int __user *optlen)
1783 {
1784         struct smc_sock *smc;
1785
1786         smc = smc_sk(sock->sk);
1787         /* socket options apply to the CLC socket */
1788         return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
1789                                              optval, optlen);
1790 }
1791
1792 static int smc_ioctl(struct socket *sock, unsigned int cmd,
1793                      unsigned long arg)
1794 {
1795         union smc_host_cursor cons, urg;
1796         struct smc_connection *conn;
1797         struct smc_sock *smc;
1798         int answ;
1799
1800         smc = smc_sk(sock->sk);
1801         conn = &smc->conn;
1802         lock_sock(&smc->sk);
1803         if (smc->use_fallback) {
1804                 if (!smc->clcsock) {
1805                         release_sock(&smc->sk);
1806                         return -EBADF;
1807                 }
1808                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
1809                 release_sock(&smc->sk);
1810                 return answ;
1811         }
1812         switch (cmd) {
1813         case SIOCINQ: /* same as FIONREAD */
1814                 if (smc->sk.sk_state == SMC_LISTEN) {
1815                         release_sock(&smc->sk);
1816                         return -EINVAL;
1817                 }
1818                 if (smc->sk.sk_state == SMC_INIT ||
1819                     smc->sk.sk_state == SMC_CLOSED)
1820                         answ = 0;
1821                 else
1822                         answ = atomic_read(&smc->conn.bytes_to_rcv);
1823                 break;
1824         case SIOCOUTQ:
1825                 /* output queue size (not send + not acked) */
1826                 if (smc->sk.sk_state == SMC_LISTEN) {
1827                         release_sock(&smc->sk);
1828                         return -EINVAL;
1829                 }
1830                 if (smc->sk.sk_state == SMC_INIT ||
1831                     smc->sk.sk_state == SMC_CLOSED)
1832                         answ = 0;
1833                 else
1834                         answ = smc->conn.sndbuf_desc->len -
1835                                         atomic_read(&smc->conn.sndbuf_space);
1836                 break;
1837         case SIOCOUTQNSD:
1838                 /* output queue size (not send only) */
1839                 if (smc->sk.sk_state == SMC_LISTEN) {
1840                         release_sock(&smc->sk);
1841                         return -EINVAL;
1842                 }
1843                 if (smc->sk.sk_state == SMC_INIT ||
1844                     smc->sk.sk_state == SMC_CLOSED)
1845                         answ = 0;
1846                 else
1847                         answ = smc_tx_prepared_sends(&smc->conn);
1848                 break;
1849         case SIOCATMARK:
1850                 if (smc->sk.sk_state == SMC_LISTEN) {
1851                         release_sock(&smc->sk);
1852                         return -EINVAL;
1853                 }
1854                 if (smc->sk.sk_state == SMC_INIT ||
1855                     smc->sk.sk_state == SMC_CLOSED) {
1856                         answ = 0;
1857                 } else {
1858                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
1859                         smc_curs_copy(&urg, &conn->urg_curs, conn);
1860                         answ = smc_curs_diff(conn->rmb_desc->len,
1861                                              &cons, &urg) == 1;
1862                 }
1863                 break;
1864         default:
1865                 release_sock(&smc->sk);
1866                 return -ENOIOCTLCMD;
1867         }
1868         release_sock(&smc->sk);
1869
1870         return put_user(answ, (int __user *)arg);
1871 }
1872
1873 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
1874                             int offset, size_t size, int flags)
1875 {
1876         struct sock *sk = sock->sk;
1877         struct smc_sock *smc;
1878         int rc = -EPIPE;
1879
1880         smc = smc_sk(sk);
1881         lock_sock(sk);
1882         if (sk->sk_state != SMC_ACTIVE) {
1883                 release_sock(sk);
1884                 goto out;
1885         }
1886         release_sock(sk);
1887         if (smc->use_fallback)
1888                 rc = kernel_sendpage(smc->clcsock, page, offset,
1889                                      size, flags);
1890         else
1891                 rc = sock_no_sendpage(sock, page, offset, size, flags);
1892
1893 out:
1894         return rc;
1895 }
1896
1897 /* Map the affected portions of the rmbe into an spd, note the number of bytes
1898  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
1899  * updates till whenever a respective page has been fully processed.
1900  * Note that subsequent recv() calls have to wait till all splice() processing
1901  * completed.
1902  */
1903 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
1904                                struct pipe_inode_info *pipe, size_t len,
1905                                unsigned int flags)
1906 {
1907         struct sock *sk = sock->sk;
1908         struct smc_sock *smc;
1909         int rc = -ENOTCONN;
1910
1911         smc = smc_sk(sk);
1912         lock_sock(sk);
1913         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
1914                 /* socket was connected before, no more data to read */
1915                 rc = 0;
1916                 goto out;
1917         }
1918         if (sk->sk_state == SMC_INIT ||
1919             sk->sk_state == SMC_LISTEN ||
1920             sk->sk_state == SMC_CLOSED)
1921                 goto out;
1922
1923         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1924                 rc = 0;
1925                 goto out;
1926         }
1927
1928         if (smc->use_fallback) {
1929                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
1930                                                     pipe, len, flags);
1931         } else {
1932                 if (*ppos) {
1933                         rc = -ESPIPE;
1934                         goto out;
1935                 }
1936                 if (flags & SPLICE_F_NONBLOCK)
1937                         flags = MSG_DONTWAIT;
1938                 else
1939                         flags = 0;
1940                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
1941         }
1942 out:
1943         release_sock(sk);
1944
1945         return rc;
1946 }
1947
1948 /* must look like tcp */
1949 static const struct proto_ops smc_sock_ops = {
1950         .family         = PF_SMC,
1951         .owner          = THIS_MODULE,
1952         .release        = smc_release,
1953         .bind           = smc_bind,
1954         .connect        = smc_connect,
1955         .socketpair     = sock_no_socketpair,
1956         .accept         = smc_accept,
1957         .getname        = smc_getname,
1958         .poll           = smc_poll,
1959         .ioctl          = smc_ioctl,
1960         .listen         = smc_listen,
1961         .shutdown       = smc_shutdown,
1962         .setsockopt     = smc_setsockopt,
1963         .getsockopt     = smc_getsockopt,
1964         .sendmsg        = smc_sendmsg,
1965         .recvmsg        = smc_recvmsg,
1966         .mmap           = sock_no_mmap,
1967         .sendpage       = smc_sendpage,
1968         .splice_read    = smc_splice_read,
1969 };
1970
1971 static int smc_create(struct net *net, struct socket *sock, int protocol,
1972                       int kern)
1973 {
1974         int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
1975         struct smc_sock *smc;
1976         struct sock *sk;
1977         int rc;
1978
1979         rc = -ESOCKTNOSUPPORT;
1980         if (sock->type != SOCK_STREAM)
1981                 goto out;
1982
1983         rc = -EPROTONOSUPPORT;
1984         if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
1985                 goto out;
1986
1987         rc = -ENOBUFS;
1988         sock->ops = &smc_sock_ops;
1989         sk = smc_sock_alloc(net, sock, protocol);
1990         if (!sk)
1991                 goto out;
1992
1993         /* create internal TCP socket for CLC handshake and fallback */
1994         smc = smc_sk(sk);
1995         smc->use_fallback = false; /* assume rdma capability first */
1996         smc->fallback_rsn = 0;
1997         rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
1998                               &smc->clcsock);
1999         if (rc) {
2000                 sk_common_release(sk);
2001                 goto out;
2002         }
2003         smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);
2004         smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);
2005
2006 out:
2007         return rc;
2008 }
2009
2010 static const struct net_proto_family smc_sock_family_ops = {
2011         .family = PF_SMC,
2012         .owner  = THIS_MODULE,
2013         .create = smc_create,
2014 };
2015
2016 unsigned int smc_net_id;
2017
2018 static __net_init int smc_net_init(struct net *net)
2019 {
2020         return smc_pnet_net_init(net);
2021 }
2022
2023 static void __net_exit smc_net_exit(struct net *net)
2024 {
2025         smc_pnet_net_exit(net);
2026 }
2027
2028 static struct pernet_operations smc_net_ops = {
2029         .init = smc_net_init,
2030         .exit = smc_net_exit,
2031         .id   = &smc_net_id,
2032         .size = sizeof(struct smc_net),
2033 };
2034
2035 static int __init smc_init(void)
2036 {
2037         int rc;
2038
2039         rc = register_pernet_subsys(&smc_net_ops);
2040         if (rc)
2041                 return rc;
2042
2043         rc = smc_pnet_init();
2044         if (rc)
2045                 goto out_pernet_subsys;
2046
2047         rc = smc_core_init();
2048         if (rc) {
2049                 pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
2050                 goto out_pnet;
2051         }
2052
2053         rc = smc_llc_init();
2054         if (rc) {
2055                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
2056                 goto out_core;
2057         }
2058
2059         rc = smc_cdc_init();
2060         if (rc) {
2061                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
2062                 goto out_core;
2063         }
2064
2065         rc = proto_register(&smc_proto, 1);
2066         if (rc) {
2067                 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
2068                 goto out_core;
2069         }
2070
2071         rc = proto_register(&smc_proto6, 1);
2072         if (rc) {
2073                 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
2074                 goto out_proto;
2075         }
2076
2077         rc = sock_register(&smc_sock_family_ops);
2078         if (rc) {
2079                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
2080                 goto out_proto6;
2081         }
2082         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
2083         INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
2084
2085         rc = smc_ib_register_client();
2086         if (rc) {
2087                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
2088                 goto out_sock;
2089         }
2090
2091         static_branch_enable(&tcp_have_smc);
2092         return 0;
2093
2094 out_sock:
2095         sock_unregister(PF_SMC);
2096 out_proto6:
2097         proto_unregister(&smc_proto6);
2098 out_proto:
2099         proto_unregister(&smc_proto);
2100 out_core:
2101         smc_core_exit();
2102 out_pnet:
2103         smc_pnet_exit();
2104 out_pernet_subsys:
2105         unregister_pernet_subsys(&smc_net_ops);
2106
2107         return rc;
2108 }
2109
2110 static void __exit smc_exit(void)
2111 {
2112         static_branch_disable(&tcp_have_smc);
2113         sock_unregister(PF_SMC);
2114         smc_core_exit();
2115         smc_ib_unregister_client();
2116         proto_unregister(&smc_proto6);
2117         proto_unregister(&smc_proto);
2118         smc_pnet_exit();
2119         unregister_pernet_subsys(&smc_net_ops);
2120         rcu_barrier();
2121 }
2122
2123 module_init(smc_init);
2124 module_exit(smc_exit);
2125
2126 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
2127 MODULE_DESCRIPTION("smc socket address family");
2128 MODULE_LICENSE("GPL");
2129 MODULE_ALIAS_NETPROTO(PF_SMC);