Merge tag 'amd-drm-next-5.8-2020-05-12' of git://people.freedesktop.org/~agd5f/linux...
[linux-2.6-microblaze.git] / net / smc / af_smc.c
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         bool is_smcd = smc->conn.lgr->is_smcd;
516
517         if (local_contact == SMC_FIRST_CONTACT)
518                 smc_lgr_cleanup_early(&smc->conn);
519         else
520                 smc_conn_free(&smc->conn);
521         if (is_smcd)
522                 /* there is only one lgr role for SMC-D; use server lock */
523                 mutex_unlock(&smc_server_lgr_pending);
524         else
525                 mutex_unlock(&smc_client_lgr_pending);
526
527         smc->connect_nonblock = 0;
528         return reason_code;
529 }
530
531 /* check if there is a rdma device available for this connection. */
532 /* called for connect and listen */
533 static int smc_find_rdma_device(struct smc_sock *smc, struct smc_init_info *ini)
534 {
535         /* PNET table look up: search active ib_device and port
536          * within same PNETID that also contains the ethernet device
537          * used for the internal TCP socket
538          */
539         smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
540         if (!ini->ib_dev)
541                 return SMC_CLC_DECL_NOSMCRDEV;
542         return 0;
543 }
544
545 /* check if there is an ISM device available for this connection. */
546 /* called for connect and listen */
547 static int smc_find_ism_device(struct smc_sock *smc, struct smc_init_info *ini)
548 {
549         /* Find ISM device with same PNETID as connecting interface  */
550         smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
551         if (!ini->ism_dev)
552                 return SMC_CLC_DECL_NOSMCDDEV;
553         return 0;
554 }
555
556 /* Check for VLAN ID and register it on ISM device just for CLC handshake */
557 static int smc_connect_ism_vlan_setup(struct smc_sock *smc,
558                                       struct smc_init_info *ini)
559 {
560         if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev, ini->vlan_id))
561                 return SMC_CLC_DECL_ISMVLANERR;
562         return 0;
563 }
564
565 /* cleanup temporary VLAN ID registration used for CLC handshake. If ISM is
566  * used, the VLAN ID will be registered again during the connection setup.
567  */
568 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc, bool is_smcd,
569                                         struct smc_init_info *ini)
570 {
571         if (!is_smcd)
572                 return 0;
573         if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev, ini->vlan_id))
574                 return SMC_CLC_DECL_CNFERR;
575         return 0;
576 }
577
578 /* CLC handshake during connect */
579 static int smc_connect_clc(struct smc_sock *smc, int smc_type,
580                            struct smc_clc_msg_accept_confirm *aclc,
581                            struct smc_init_info *ini)
582 {
583         int rc = 0;
584
585         /* do inband token exchange */
586         rc = smc_clc_send_proposal(smc, smc_type, ini);
587         if (rc)
588                 return rc;
589         /* receive SMC Accept CLC message */
590         return smc_clc_wait_msg(smc, aclc, sizeof(*aclc), SMC_CLC_ACCEPT,
591                                 CLC_WAIT_TIME);
592 }
593
594 /* setup for RDMA connection of client */
595 static int smc_connect_rdma(struct smc_sock *smc,
596                             struct smc_clc_msg_accept_confirm *aclc,
597                             struct smc_init_info *ini)
598 {
599         struct smc_link *link;
600         int reason_code = 0;
601
602         ini->is_smcd = false;
603         ini->ib_lcl = &aclc->lcl;
604         ini->ib_clcqpn = ntoh24(aclc->qpn);
605         ini->srv_first_contact = aclc->hdr.flag;
606
607         mutex_lock(&smc_client_lgr_pending);
608         reason_code = smc_conn_create(smc, ini);
609         if (reason_code) {
610                 mutex_unlock(&smc_client_lgr_pending);
611                 return reason_code;
612         }
613         link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK];
614
615         smc_conn_save_peer_info(smc, aclc);
616
617         /* create send buffer and rmb */
618         if (smc_buf_create(smc, false))
619                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM,
620                                          ini->cln_first_contact);
621
622         if (ini->cln_first_contact == SMC_FIRST_CONTACT)
623                 smc_link_save_peer_info(link, aclc);
624
625         if (smc_rmb_rtoken_handling(&smc->conn, aclc))
626                 return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RTOK,
627                                          ini->cln_first_contact);
628
629         smc_close_init(smc);
630         smc_rx_init(smc);
631
632         if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
633                 if (smc_ib_ready_link(link))
634                         return smc_connect_abort(smc, SMC_CLC_DECL_ERR_RDYLNK,
635                                                  ini->cln_first_contact);
636         } else {
637                 if (smc_reg_rmb(link, smc->conn.rmb_desc, true))
638                         return smc_connect_abort(smc, SMC_CLC_DECL_ERR_REGRMB,
639                                                  ini->cln_first_contact);
640         }
641         smc_rmb_sync_sg_for_device(&smc->conn);
642
643         reason_code = smc_clc_send_confirm(smc);
644         if (reason_code)
645                 return smc_connect_abort(smc, reason_code,
646                                          ini->cln_first_contact);
647
648         smc_tx_init(smc);
649
650         if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
651                 /* QP confirmation over RoCE fabric */
652                 reason_code = smc_clnt_conf_first_link(smc);
653                 if (reason_code)
654                         return smc_connect_abort(smc, reason_code,
655                                                  ini->cln_first_contact);
656         }
657         mutex_unlock(&smc_client_lgr_pending);
658
659         smc_copy_sock_settings_to_clc(smc);
660         smc->connect_nonblock = 0;
661         if (smc->sk.sk_state == SMC_INIT)
662                 smc->sk.sk_state = SMC_ACTIVE;
663
664         return 0;
665 }
666
667 /* setup for ISM connection of client */
668 static int smc_connect_ism(struct smc_sock *smc,
669                            struct smc_clc_msg_accept_confirm *aclc,
670                            struct smc_init_info *ini)
671 {
672         int rc = 0;
673
674         ini->is_smcd = true;
675         ini->ism_gid = aclc->gid;
676         ini->srv_first_contact = aclc->hdr.flag;
677
678         /* there is only one lgr role for SMC-D; use server lock */
679         mutex_lock(&smc_server_lgr_pending);
680         rc = smc_conn_create(smc, ini);
681         if (rc) {
682                 mutex_unlock(&smc_server_lgr_pending);
683                 return rc;
684         }
685
686         /* Create send and receive buffers */
687         if (smc_buf_create(smc, true))
688                 return smc_connect_abort(smc, SMC_CLC_DECL_MEM,
689                                          ini->cln_first_contact);
690
691         smc_conn_save_peer_info(smc, aclc);
692         smc_close_init(smc);
693         smc_rx_init(smc);
694         smc_tx_init(smc);
695
696         rc = smc_clc_send_confirm(smc);
697         if (rc)
698                 return smc_connect_abort(smc, rc, ini->cln_first_contact);
699         mutex_unlock(&smc_server_lgr_pending);
700
701         smc_copy_sock_settings_to_clc(smc);
702         smc->connect_nonblock = 0;
703         if (smc->sk.sk_state == SMC_INIT)
704                 smc->sk.sk_state = SMC_ACTIVE;
705
706         return 0;
707 }
708
709 /* perform steps before actually connecting */
710 static int __smc_connect(struct smc_sock *smc)
711 {
712         bool ism_supported = false, rdma_supported = false;
713         struct smc_clc_msg_accept_confirm aclc;
714         struct smc_init_info ini = {0};
715         int smc_type;
716         int rc = 0;
717
718         if (smc->use_fallback)
719                 return smc_connect_fallback(smc, smc->fallback_rsn);
720
721         /* if peer has not signalled SMC-capability, fall back */
722         if (!tcp_sk(smc->clcsock->sk)->syn_smc)
723                 return smc_connect_fallback(smc, SMC_CLC_DECL_PEERNOSMC);
724
725         /* IPSec connections opt out of SMC-R optimizations */
726         if (using_ipsec(smc))
727                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_IPSEC);
728
729         /* get vlan id from IP device */
730         if (smc_vlan_by_tcpsk(smc->clcsock, &ini))
731                 return smc_connect_decline_fallback(smc,
732                                                     SMC_CLC_DECL_GETVLANERR);
733
734         /* check if there is an ism device available */
735         if (!smc_find_ism_device(smc, &ini) &&
736             !smc_connect_ism_vlan_setup(smc, &ini)) {
737                 /* ISM is supported for this connection */
738                 ism_supported = true;
739                 smc_type = SMC_TYPE_D;
740         }
741
742         /* check if there is a rdma device available */
743         if (!smc_find_rdma_device(smc, &ini)) {
744                 /* RDMA is supported for this connection */
745                 rdma_supported = true;
746                 if (ism_supported)
747                         smc_type = SMC_TYPE_B; /* both */
748                 else
749                         smc_type = SMC_TYPE_R; /* only RDMA */
750         }
751
752         /* if neither ISM nor RDMA are supported, fallback */
753         if (!rdma_supported && !ism_supported)
754                 return smc_connect_decline_fallback(smc, SMC_CLC_DECL_NOSMCDEV);
755
756         /* perform CLC handshake */
757         rc = smc_connect_clc(smc, smc_type, &aclc, &ini);
758         if (rc) {
759                 smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
760                 return smc_connect_decline_fallback(smc, rc);
761         }
762
763         /* depending on previous steps, connect using rdma or ism */
764         if (rdma_supported && aclc.hdr.path == SMC_TYPE_R)
765                 rc = smc_connect_rdma(smc, &aclc, &ini);
766         else if (ism_supported && aclc.hdr.path == SMC_TYPE_D)
767                 rc = smc_connect_ism(smc, &aclc, &ini);
768         else
769                 rc = SMC_CLC_DECL_MODEUNSUPP;
770         if (rc) {
771                 smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
772                 return smc_connect_decline_fallback(smc, rc);
773         }
774
775         smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
776         return 0;
777 }
778
779 static void smc_connect_work(struct work_struct *work)
780 {
781         struct smc_sock *smc = container_of(work, struct smc_sock,
782                                             connect_work);
783         long timeo = smc->sk.sk_sndtimeo;
784         int rc = 0;
785
786         if (!timeo)
787                 timeo = MAX_SCHEDULE_TIMEOUT;
788         lock_sock(smc->clcsock->sk);
789         if (smc->clcsock->sk->sk_err) {
790                 smc->sk.sk_err = smc->clcsock->sk->sk_err;
791         } else if ((1 << smc->clcsock->sk->sk_state) &
792                                         (TCPF_SYN_SENT | TCP_SYN_RECV)) {
793                 rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo);
794                 if ((rc == -EPIPE) &&
795                     ((1 << smc->clcsock->sk->sk_state) &
796                                         (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)))
797                         rc = 0;
798         }
799         release_sock(smc->clcsock->sk);
800         lock_sock(&smc->sk);
801         if (rc != 0 || smc->sk.sk_err) {
802                 smc->sk.sk_state = SMC_CLOSED;
803                 if (rc == -EPIPE || rc == -EAGAIN)
804                         smc->sk.sk_err = EPIPE;
805                 else if (signal_pending(current))
806                         smc->sk.sk_err = -sock_intr_errno(timeo);
807                 sock_put(&smc->sk); /* passive closing */
808                 goto out;
809         }
810
811         rc = __smc_connect(smc);
812         if (rc < 0)
813                 smc->sk.sk_err = -rc;
814
815 out:
816         if (!sock_flag(&smc->sk, SOCK_DEAD)) {
817                 if (smc->sk.sk_err) {
818                         smc->sk.sk_state_change(&smc->sk);
819                 } else { /* allow polling before and after fallback decision */
820                         smc->clcsock->sk->sk_write_space(smc->clcsock->sk);
821                         smc->sk.sk_write_space(&smc->sk);
822                 }
823         }
824         release_sock(&smc->sk);
825 }
826
827 static int smc_connect(struct socket *sock, struct sockaddr *addr,
828                        int alen, int flags)
829 {
830         struct sock *sk = sock->sk;
831         struct smc_sock *smc;
832         int rc = -EINVAL;
833
834         smc = smc_sk(sk);
835
836         /* separate smc parameter checking to be safe */
837         if (alen < sizeof(addr->sa_family))
838                 goto out_err;
839         if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
840                 goto out_err;
841
842         lock_sock(sk);
843         switch (sk->sk_state) {
844         default:
845                 goto out;
846         case SMC_ACTIVE:
847                 rc = -EISCONN;
848                 goto out;
849         case SMC_INIT:
850                 rc = 0;
851                 break;
852         }
853
854         smc_copy_sock_settings_to_clc(smc);
855         tcp_sk(smc->clcsock->sk)->syn_smc = 1;
856         if (smc->connect_nonblock) {
857                 rc = -EALREADY;
858                 goto out;
859         }
860         rc = kernel_connect(smc->clcsock, addr, alen, flags);
861         if (rc && rc != -EINPROGRESS)
862                 goto out;
863
864         sock_hold(&smc->sk); /* sock put in passive closing */
865         if (smc->use_fallback)
866                 goto out;
867         if (flags & O_NONBLOCK) {
868                 if (schedule_work(&smc->connect_work))
869                         smc->connect_nonblock = 1;
870                 rc = -EINPROGRESS;
871         } else {
872                 rc = __smc_connect(smc);
873                 if (rc < 0)
874                         goto out;
875                 else
876                         rc = 0; /* success cases including fallback */
877         }
878
879 out:
880         release_sock(sk);
881 out_err:
882         return rc;
883 }
884
885 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
886 {
887         struct socket *new_clcsock = NULL;
888         struct sock *lsk = &lsmc->sk;
889         struct sock *new_sk;
890         int rc = -EINVAL;
891
892         release_sock(lsk);
893         new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
894         if (!new_sk) {
895                 rc = -ENOMEM;
896                 lsk->sk_err = ENOMEM;
897                 *new_smc = NULL;
898                 lock_sock(lsk);
899                 goto out;
900         }
901         *new_smc = smc_sk(new_sk);
902
903         mutex_lock(&lsmc->clcsock_release_lock);
904         if (lsmc->clcsock)
905                 rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0);
906         mutex_unlock(&lsmc->clcsock_release_lock);
907         lock_sock(lsk);
908         if  (rc < 0)
909                 lsk->sk_err = -rc;
910         if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
911                 new_sk->sk_prot->unhash(new_sk);
912                 if (new_clcsock)
913                         sock_release(new_clcsock);
914                 new_sk->sk_state = SMC_CLOSED;
915                 sock_set_flag(new_sk, SOCK_DEAD);
916                 sock_put(new_sk); /* final */
917                 *new_smc = NULL;
918                 goto out;
919         }
920
921         (*new_smc)->clcsock = new_clcsock;
922 out:
923         return rc;
924 }
925
926 /* add a just created sock to the accept queue of the listen sock as
927  * candidate for a following socket accept call from user space
928  */
929 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
930 {
931         struct smc_sock *par = smc_sk(parent);
932
933         sock_hold(sk); /* sock_put in smc_accept_unlink () */
934         spin_lock(&par->accept_q_lock);
935         list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q);
936         spin_unlock(&par->accept_q_lock);
937         sk_acceptq_added(parent);
938 }
939
940 /* remove a socket from the accept queue of its parental listening socket */
941 static void smc_accept_unlink(struct sock *sk)
942 {
943         struct smc_sock *par = smc_sk(sk)->listen_smc;
944
945         spin_lock(&par->accept_q_lock);
946         list_del_init(&smc_sk(sk)->accept_q);
947         spin_unlock(&par->accept_q_lock);
948         sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk);
949         sock_put(sk); /* sock_hold in smc_accept_enqueue */
950 }
951
952 /* remove a sock from the accept queue to bind it to a new socket created
953  * for a socket accept call from user space
954  */
955 struct sock *smc_accept_dequeue(struct sock *parent,
956                                 struct socket *new_sock)
957 {
958         struct smc_sock *isk, *n;
959         struct sock *new_sk;
960
961         list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
962                 new_sk = (struct sock *)isk;
963
964                 smc_accept_unlink(new_sk);
965                 if (new_sk->sk_state == SMC_CLOSED) {
966                         new_sk->sk_prot->unhash(new_sk);
967                         if (isk->clcsock) {
968                                 sock_release(isk->clcsock);
969                                 isk->clcsock = NULL;
970                         }
971                         sock_put(new_sk); /* final */
972                         continue;
973                 }
974                 if (new_sock) {
975                         sock_graft(new_sk, new_sock);
976                         if (isk->use_fallback) {
977                                 smc_sk(new_sk)->clcsock->file = new_sock->file;
978                                 isk->clcsock->file->private_data = isk->clcsock;
979                         }
980                 }
981                 return new_sk;
982         }
983         return NULL;
984 }
985
986 /* clean up for a created but never accepted sock */
987 void smc_close_non_accepted(struct sock *sk)
988 {
989         struct smc_sock *smc = smc_sk(sk);
990
991         sock_hold(sk); /* sock_put below */
992         lock_sock(sk);
993         if (!sk->sk_lingertime)
994                 /* wait for peer closing */
995                 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
996         __smc_release(smc);
997         release_sock(sk);
998         sock_put(sk); /* sock_hold above */
999         sock_put(sk); /* final sock_put */
1000 }
1001
1002 static int smc_serv_conf_first_link(struct smc_sock *smc)
1003 {
1004         struct net *net = sock_net(smc->clcsock->sk);
1005         struct smc_link_group *lgr = smc->conn.lgr;
1006         struct smc_link *link;
1007         int rest;
1008         int rc;
1009
1010         link = &lgr->lnk[SMC_SINGLE_LINK];
1011
1012         if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
1013                 return SMC_CLC_DECL_ERR_REGRMB;
1014
1015         /* send CONFIRM LINK request to client over the RoCE fabric */
1016         rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1017         if (rc < 0)
1018                 return SMC_CLC_DECL_TIMEOUT_CL;
1019
1020         /* receive CONFIRM LINK response from client over the RoCE fabric */
1021         rest = wait_for_completion_interruptible_timeout(
1022                 &link->llc_confirm_resp,
1023                 SMC_LLC_WAIT_FIRST_TIME);
1024         if (rest <= 0) {
1025                 struct smc_clc_msg_decline dclc;
1026
1027                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1028                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1029                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_CL : rc;
1030         }
1031
1032         if (link->llc_confirm_resp_rc)
1033                 return SMC_CLC_DECL_RMBE_EC;
1034
1035         /* send ADD LINK request to client over the RoCE fabric */
1036         rc = smc_llc_send_add_link(link,
1037                                    link->smcibdev->mac[link->ibport - 1],
1038                                    link->gid, SMC_LLC_REQ);
1039         if (rc < 0)
1040                 return SMC_CLC_DECL_TIMEOUT_AL;
1041
1042         /* receive ADD LINK response from client over the RoCE fabric */
1043         rest = wait_for_completion_interruptible_timeout(&link->llc_add_resp,
1044                                                          SMC_LLC_WAIT_TIME);
1045         if (rest <= 0) {
1046                 struct smc_clc_msg_decline dclc;
1047
1048                 rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc),
1049                                       SMC_CLC_DECLINE, CLC_WAIT_TIME_SHORT);
1050                 return rc == -EAGAIN ? SMC_CLC_DECL_TIMEOUT_AL : rc;
1051         }
1052
1053         smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
1054
1055         return 0;
1056 }
1057
1058 /* listen worker: finish */
1059 static void smc_listen_out(struct smc_sock *new_smc)
1060 {
1061         struct smc_sock *lsmc = new_smc->listen_smc;
1062         struct sock *newsmcsk = &new_smc->sk;
1063
1064         if (lsmc->sk.sk_state == SMC_LISTEN) {
1065                 lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING);
1066                 smc_accept_enqueue(&lsmc->sk, newsmcsk);
1067                 release_sock(&lsmc->sk);
1068         } else { /* no longer listening */
1069                 smc_close_non_accepted(newsmcsk);
1070         }
1071
1072         /* Wake up accept */
1073         lsmc->sk.sk_data_ready(&lsmc->sk);
1074         sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1075 }
1076
1077 /* listen worker: finish in state connected */
1078 static void smc_listen_out_connected(struct smc_sock *new_smc)
1079 {
1080         struct sock *newsmcsk = &new_smc->sk;
1081
1082         sk_refcnt_debug_inc(newsmcsk);
1083         if (newsmcsk->sk_state == SMC_INIT)
1084                 newsmcsk->sk_state = SMC_ACTIVE;
1085
1086         smc_listen_out(new_smc);
1087 }
1088
1089 /* listen worker: finish in error state */
1090 static void smc_listen_out_err(struct smc_sock *new_smc)
1091 {
1092         struct sock *newsmcsk = &new_smc->sk;
1093
1094         if (newsmcsk->sk_state == SMC_INIT)
1095                 sock_put(&new_smc->sk); /* passive closing */
1096         newsmcsk->sk_state = SMC_CLOSED;
1097
1098         smc_listen_out(new_smc);
1099 }
1100
1101 /* listen worker: decline and fall back if possible */
1102 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
1103                                int local_contact)
1104 {
1105         /* RDMA setup failed, switch back to TCP */
1106         if (local_contact == SMC_FIRST_CONTACT)
1107                 smc_lgr_cleanup_early(&new_smc->conn);
1108         else
1109                 smc_conn_free(&new_smc->conn);
1110         if (reason_code < 0) { /* error, no fallback possible */
1111                 smc_listen_out_err(new_smc);
1112                 return;
1113         }
1114         smc_switch_to_fallback(new_smc);
1115         new_smc->fallback_rsn = reason_code;
1116         if (reason_code && reason_code != SMC_CLC_DECL_PEERDECL) {
1117                 if (smc_clc_send_decline(new_smc, reason_code) < 0) {
1118                         smc_listen_out_err(new_smc);
1119                         return;
1120                 }
1121         }
1122         smc_listen_out_connected(new_smc);
1123 }
1124
1125 /* listen worker: check prefixes */
1126 static int smc_listen_prfx_check(struct smc_sock *new_smc,
1127                                  struct smc_clc_msg_proposal *pclc)
1128 {
1129         struct smc_clc_msg_proposal_prefix *pclc_prfx;
1130         struct socket *newclcsock = new_smc->clcsock;
1131
1132         pclc_prfx = smc_clc_proposal_get_prefix(pclc);
1133         if (smc_clc_prfx_match(newclcsock, pclc_prfx))
1134                 return SMC_CLC_DECL_DIFFPREFIX;
1135
1136         return 0;
1137 }
1138
1139 /* listen worker: initialize connection and buffers */
1140 static int smc_listen_rdma_init(struct smc_sock *new_smc,
1141                                 struct smc_init_info *ini)
1142 {
1143         int rc;
1144
1145         /* allocate connection / link group */
1146         rc = smc_conn_create(new_smc, ini);
1147         if (rc)
1148                 return rc;
1149
1150         /* create send buffer and rmb */
1151         if (smc_buf_create(new_smc, false))
1152                 return SMC_CLC_DECL_MEM;
1153
1154         return 0;
1155 }
1156
1157 /* listen worker: initialize connection and buffers for SMC-D */
1158 static int smc_listen_ism_init(struct smc_sock *new_smc,
1159                                struct smc_clc_msg_proposal *pclc,
1160                                struct smc_init_info *ini)
1161 {
1162         struct smc_clc_msg_smcd *pclc_smcd;
1163         int rc;
1164
1165         pclc_smcd = smc_get_clc_msg_smcd(pclc);
1166         ini->ism_gid = pclc_smcd->gid;
1167         rc = smc_conn_create(new_smc, ini);
1168         if (rc)
1169                 return rc;
1170
1171         /* Check if peer can be reached via ISM device */
1172         if (smc_ism_cantalk(new_smc->conn.lgr->peer_gid,
1173                             new_smc->conn.lgr->vlan_id,
1174                             new_smc->conn.lgr->smcd)) {
1175                 if (ini->cln_first_contact == SMC_FIRST_CONTACT)
1176                         smc_lgr_cleanup_early(&new_smc->conn);
1177                 else
1178                         smc_conn_free(&new_smc->conn);
1179                 return SMC_CLC_DECL_SMCDNOTALK;
1180         }
1181
1182         /* Create send and receive buffers */
1183         if (smc_buf_create(new_smc, true)) {
1184                 if (ini->cln_first_contact == SMC_FIRST_CONTACT)
1185                         smc_lgr_cleanup_early(&new_smc->conn);
1186                 else
1187                         smc_conn_free(&new_smc->conn);
1188                 return SMC_CLC_DECL_MEM;
1189         }
1190
1191         return 0;
1192 }
1193
1194 /* listen worker: register buffers */
1195 static int smc_listen_rdma_reg(struct smc_sock *new_smc, int local_contact)
1196 {
1197         struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1198
1199         if (local_contact != SMC_FIRST_CONTACT) {
1200                 if (smc_reg_rmb(link, new_smc->conn.rmb_desc, true))
1201                         return SMC_CLC_DECL_ERR_REGRMB;
1202         }
1203         smc_rmb_sync_sg_for_device(&new_smc->conn);
1204
1205         return 0;
1206 }
1207
1208 /* listen worker: finish RDMA setup */
1209 static int smc_listen_rdma_finish(struct smc_sock *new_smc,
1210                                   struct smc_clc_msg_accept_confirm *cclc,
1211                                   int local_contact)
1212 {
1213         struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1214         int reason_code = 0;
1215
1216         if (local_contact == SMC_FIRST_CONTACT)
1217                 smc_link_save_peer_info(link, cclc);
1218
1219         if (smc_rmb_rtoken_handling(&new_smc->conn, cclc)) {
1220                 reason_code = SMC_CLC_DECL_ERR_RTOK;
1221                 goto decline;
1222         }
1223
1224         if (local_contact == SMC_FIRST_CONTACT) {
1225                 if (smc_ib_ready_link(link)) {
1226                         reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1227                         goto decline;
1228                 }
1229                 /* QP confirmation over RoCE fabric */
1230                 reason_code = smc_serv_conf_first_link(new_smc);
1231                 if (reason_code)
1232                         goto decline;
1233         }
1234         return 0;
1235
1236 decline:
1237         smc_listen_decline(new_smc, reason_code, local_contact);
1238         return reason_code;
1239 }
1240
1241 /* setup for RDMA connection of server */
1242 static void smc_listen_work(struct work_struct *work)
1243 {
1244         struct smc_sock *new_smc = container_of(work, struct smc_sock,
1245                                                 smc_listen_work);
1246         struct socket *newclcsock = new_smc->clcsock;
1247         struct smc_clc_msg_accept_confirm cclc;
1248         struct smc_clc_msg_proposal *pclc;
1249         struct smc_init_info ini = {0};
1250         bool ism_supported = false;
1251         u8 buf[SMC_CLC_MAX_LEN];
1252         int rc = 0;
1253
1254         if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
1255                 return smc_listen_out_err(new_smc);
1256
1257         if (new_smc->use_fallback) {
1258                 smc_listen_out_connected(new_smc);
1259                 return;
1260         }
1261
1262         /* check if peer is smc capable */
1263         if (!tcp_sk(newclcsock->sk)->syn_smc) {
1264                 smc_switch_to_fallback(new_smc);
1265                 new_smc->fallback_rsn = SMC_CLC_DECL_PEERNOSMC;
1266                 smc_listen_out_connected(new_smc);
1267                 return;
1268         }
1269
1270         /* do inband token exchange -
1271          * wait for and receive SMC Proposal CLC message
1272          */
1273         pclc = (struct smc_clc_msg_proposal *)&buf;
1274         rc = smc_clc_wait_msg(new_smc, pclc, SMC_CLC_MAX_LEN,
1275                               SMC_CLC_PROPOSAL, CLC_WAIT_TIME);
1276         if (rc)
1277                 goto out_decl;
1278
1279         /* IPSec connections opt out of SMC-R optimizations */
1280         if (using_ipsec(new_smc)) {
1281                 rc = SMC_CLC_DECL_IPSEC;
1282                 goto out_decl;
1283         }
1284
1285         /* check for matching IP prefix and subnet length */
1286         rc = smc_listen_prfx_check(new_smc, pclc);
1287         if (rc)
1288                 goto out_decl;
1289
1290         /* get vlan id from IP device */
1291         if (smc_vlan_by_tcpsk(new_smc->clcsock, &ini)) {
1292                 rc = SMC_CLC_DECL_GETVLANERR;
1293                 goto out_decl;
1294         }
1295
1296         mutex_lock(&smc_server_lgr_pending);
1297         smc_close_init(new_smc);
1298         smc_rx_init(new_smc);
1299         smc_tx_init(new_smc);
1300
1301         /* check if ISM is available */
1302         if (pclc->hdr.path == SMC_TYPE_D || pclc->hdr.path == SMC_TYPE_B) {
1303                 ini.is_smcd = true; /* prepare ISM check */
1304                 rc = smc_find_ism_device(new_smc, &ini);
1305                 if (!rc)
1306                         rc = smc_listen_ism_init(new_smc, pclc, &ini);
1307                 if (!rc)
1308                         ism_supported = true;
1309                 else if (pclc->hdr.path == SMC_TYPE_D)
1310                         goto out_unlock; /* skip RDMA and decline */
1311         }
1312
1313         /* check if RDMA is available */
1314         if (!ism_supported) { /* SMC_TYPE_R or SMC_TYPE_B */
1315                 /* prepare RDMA check */
1316                 ini.is_smcd = false;
1317                 ini.ism_dev = NULL;
1318                 ini.ib_lcl = &pclc->lcl;
1319                 rc = smc_find_rdma_device(new_smc, &ini);
1320                 if (rc) {
1321                         /* no RDMA device found */
1322                         if (pclc->hdr.path == SMC_TYPE_B)
1323                                 /* neither ISM nor RDMA device found */
1324                                 rc = SMC_CLC_DECL_NOSMCDEV;
1325                         goto out_unlock;
1326                 }
1327                 rc = smc_listen_rdma_init(new_smc, &ini);
1328                 if (rc)
1329                         goto out_unlock;
1330                 rc = smc_listen_rdma_reg(new_smc, ini.cln_first_contact);
1331                 if (rc)
1332                         goto out_unlock;
1333         }
1334
1335         /* send SMC Accept CLC message */
1336         rc = smc_clc_send_accept(new_smc, ini.cln_first_contact);
1337         if (rc)
1338                 goto out_unlock;
1339
1340         /* SMC-D does not need this lock any more */
1341         if (ism_supported)
1342                 mutex_unlock(&smc_server_lgr_pending);
1343
1344         /* receive SMC Confirm CLC message */
1345         rc = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
1346                               SMC_CLC_CONFIRM, CLC_WAIT_TIME);
1347         if (rc) {
1348                 if (!ism_supported)
1349                         goto out_unlock;
1350                 goto out_decl;
1351         }
1352
1353         /* finish worker */
1354         if (!ism_supported) {
1355                 rc = smc_listen_rdma_finish(new_smc, &cclc,
1356                                             ini.cln_first_contact);
1357                 mutex_unlock(&smc_server_lgr_pending);
1358                 if (rc)
1359                         return;
1360         }
1361         smc_conn_save_peer_info(new_smc, &cclc);
1362         smc_listen_out_connected(new_smc);
1363         return;
1364
1365 out_unlock:
1366         mutex_unlock(&smc_server_lgr_pending);
1367 out_decl:
1368         smc_listen_decline(new_smc, rc, ini.cln_first_contact);
1369 }
1370
1371 static void smc_tcp_listen_work(struct work_struct *work)
1372 {
1373         struct smc_sock *lsmc = container_of(work, struct smc_sock,
1374                                              tcp_listen_work);
1375         struct sock *lsk = &lsmc->sk;
1376         struct smc_sock *new_smc;
1377         int rc = 0;
1378
1379         lock_sock(lsk);
1380         while (lsk->sk_state == SMC_LISTEN) {
1381                 rc = smc_clcsock_accept(lsmc, &new_smc);
1382                 if (rc)
1383                         goto out;
1384                 if (!new_smc)
1385                         continue;
1386
1387                 new_smc->listen_smc = lsmc;
1388                 new_smc->use_fallback = lsmc->use_fallback;
1389                 new_smc->fallback_rsn = lsmc->fallback_rsn;
1390                 sock_hold(lsk); /* sock_put in smc_listen_work */
1391                 INIT_WORK(&new_smc->smc_listen_work, smc_listen_work);
1392                 smc_copy_sock_settings_to_smc(new_smc);
1393                 new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf;
1394                 new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf;
1395                 sock_hold(&new_smc->sk); /* sock_put in passive closing */
1396                 if (!schedule_work(&new_smc->smc_listen_work))
1397                         sock_put(&new_smc->sk);
1398         }
1399
1400 out:
1401         release_sock(lsk);
1402         sock_put(&lsmc->sk); /* sock_hold in smc_listen */
1403 }
1404
1405 static int smc_listen(struct socket *sock, int backlog)
1406 {
1407         struct sock *sk = sock->sk;
1408         struct smc_sock *smc;
1409         int rc;
1410
1411         smc = smc_sk(sk);
1412         lock_sock(sk);
1413
1414         rc = -EINVAL;
1415         if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
1416             smc->connect_nonblock)
1417                 goto out;
1418
1419         rc = 0;
1420         if (sk->sk_state == SMC_LISTEN) {
1421                 sk->sk_max_ack_backlog = backlog;
1422                 goto out;
1423         }
1424         /* some socket options are handled in core, so we could not apply
1425          * them to the clc socket -- copy smc socket options to clc socket
1426          */
1427         smc_copy_sock_settings_to_clc(smc);
1428         if (!smc->use_fallback)
1429                 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1430
1431         rc = kernel_listen(smc->clcsock, backlog);
1432         if (rc)
1433                 goto out;
1434         sk->sk_max_ack_backlog = backlog;
1435         sk->sk_ack_backlog = 0;
1436         sk->sk_state = SMC_LISTEN;
1437         sock_hold(sk); /* sock_hold in tcp_listen_worker */
1438         if (!schedule_work(&smc->tcp_listen_work))
1439                 sock_put(sk);
1440
1441 out:
1442         release_sock(sk);
1443         return rc;
1444 }
1445
1446 static int smc_accept(struct socket *sock, struct socket *new_sock,
1447                       int flags, bool kern)
1448 {
1449         struct sock *sk = sock->sk, *nsk;
1450         DECLARE_WAITQUEUE(wait, current);
1451         struct smc_sock *lsmc;
1452         long timeo;
1453         int rc = 0;
1454
1455         lsmc = smc_sk(sk);
1456         sock_hold(sk); /* sock_put below */
1457         lock_sock(sk);
1458
1459         if (lsmc->sk.sk_state != SMC_LISTEN) {
1460                 rc = -EINVAL;
1461                 release_sock(sk);
1462                 goto out;
1463         }
1464
1465         /* Wait for an incoming connection */
1466         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
1467         add_wait_queue_exclusive(sk_sleep(sk), &wait);
1468         while (!(nsk = smc_accept_dequeue(sk, new_sock))) {
1469                 set_current_state(TASK_INTERRUPTIBLE);
1470                 if (!timeo) {
1471                         rc = -EAGAIN;
1472                         break;
1473                 }
1474                 release_sock(sk);
1475                 timeo = schedule_timeout(timeo);
1476                 /* wakeup by sk_data_ready in smc_listen_work() */
1477                 sched_annotate_sleep();
1478                 lock_sock(sk);
1479                 if (signal_pending(current)) {
1480                         rc = sock_intr_errno(timeo);
1481                         break;
1482                 }
1483         }
1484         set_current_state(TASK_RUNNING);
1485         remove_wait_queue(sk_sleep(sk), &wait);
1486
1487         if (!rc)
1488                 rc = sock_error(nsk);
1489         release_sock(sk);
1490         if (rc)
1491                 goto out;
1492
1493         if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
1494                 /* wait till data arrives on the socket */
1495                 timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
1496                                                                 MSEC_PER_SEC);
1497                 if (smc_sk(nsk)->use_fallback) {
1498                         struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
1499
1500                         lock_sock(clcsk);
1501                         if (skb_queue_empty(&clcsk->sk_receive_queue))
1502                                 sk_wait_data(clcsk, &timeo, NULL);
1503                         release_sock(clcsk);
1504                 } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
1505                         lock_sock(nsk);
1506                         smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
1507                         release_sock(nsk);
1508                 }
1509         }
1510
1511 out:
1512         sock_put(sk); /* sock_hold above */
1513         return rc;
1514 }
1515
1516 static int smc_getname(struct socket *sock, struct sockaddr *addr,
1517                        int peer)
1518 {
1519         struct smc_sock *smc;
1520
1521         if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
1522             (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
1523                 return -ENOTCONN;
1524
1525         smc = smc_sk(sock->sk);
1526
1527         return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
1528 }
1529
1530 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1531 {
1532         struct sock *sk = sock->sk;
1533         struct smc_sock *smc;
1534         int rc = -EPIPE;
1535
1536         smc = smc_sk(sk);
1537         lock_sock(sk);
1538         if ((sk->sk_state != SMC_ACTIVE) &&
1539             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1540             (sk->sk_state != SMC_INIT))
1541                 goto out;
1542
1543         if (msg->msg_flags & MSG_FASTOPEN) {
1544                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
1545                         smc_switch_to_fallback(smc);
1546                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
1547                 } else {
1548                         rc = -EINVAL;
1549                         goto out;
1550                 }
1551         }
1552
1553         if (smc->use_fallback)
1554                 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
1555         else
1556                 rc = smc_tx_sendmsg(smc, msg, len);
1557 out:
1558         release_sock(sk);
1559         return rc;
1560 }
1561
1562 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1563                        int flags)
1564 {
1565         struct sock *sk = sock->sk;
1566         struct smc_sock *smc;
1567         int rc = -ENOTCONN;
1568
1569         smc = smc_sk(sk);
1570         lock_sock(sk);
1571         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
1572                 /* socket was connected before, no more data to read */
1573                 rc = 0;
1574                 goto out;
1575         }
1576         if ((sk->sk_state == SMC_INIT) ||
1577             (sk->sk_state == SMC_LISTEN) ||
1578             (sk->sk_state == SMC_CLOSED))
1579                 goto out;
1580
1581         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1582                 rc = 0;
1583                 goto out;
1584         }
1585
1586         if (smc->use_fallback) {
1587                 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
1588         } else {
1589                 msg->msg_namelen = 0;
1590                 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
1591         }
1592
1593 out:
1594         release_sock(sk);
1595         return rc;
1596 }
1597
1598 static __poll_t smc_accept_poll(struct sock *parent)
1599 {
1600         struct smc_sock *isk = smc_sk(parent);
1601         __poll_t mask = 0;
1602
1603         spin_lock(&isk->accept_q_lock);
1604         if (!list_empty(&isk->accept_q))
1605                 mask = EPOLLIN | EPOLLRDNORM;
1606         spin_unlock(&isk->accept_q_lock);
1607
1608         return mask;
1609 }
1610
1611 static __poll_t smc_poll(struct file *file, struct socket *sock,
1612                              poll_table *wait)
1613 {
1614         struct sock *sk = sock->sk;
1615         struct smc_sock *smc;
1616         __poll_t mask = 0;
1617
1618         if (!sk)
1619                 return EPOLLNVAL;
1620
1621         smc = smc_sk(sock->sk);
1622         if (smc->use_fallback) {
1623                 /* delegate to CLC child sock */
1624                 mask = smc->clcsock->ops->poll(file, smc->clcsock, wait);
1625                 sk->sk_err = smc->clcsock->sk->sk_err;
1626         } else {
1627                 if (sk->sk_state != SMC_CLOSED)
1628                         sock_poll_wait(file, sock, wait);
1629                 if (sk->sk_err)
1630                         mask |= EPOLLERR;
1631                 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
1632                     (sk->sk_state == SMC_CLOSED))
1633                         mask |= EPOLLHUP;
1634                 if (sk->sk_state == SMC_LISTEN) {
1635                         /* woken up by sk_data_ready in smc_listen_work() */
1636                         mask |= smc_accept_poll(sk);
1637                 } else if (smc->use_fallback) { /* as result of connect_work()*/
1638                         mask |= smc->clcsock->ops->poll(file, smc->clcsock,
1639                                                            wait);
1640                         sk->sk_err = smc->clcsock->sk->sk_err;
1641                 } else {
1642                         if ((sk->sk_state != SMC_INIT &&
1643                              atomic_read(&smc->conn.sndbuf_space)) ||
1644                             sk->sk_shutdown & SEND_SHUTDOWN) {
1645                                 mask |= EPOLLOUT | EPOLLWRNORM;
1646                         } else {
1647                                 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1648                                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1649                         }
1650                         if (atomic_read(&smc->conn.bytes_to_rcv))
1651                                 mask |= EPOLLIN | EPOLLRDNORM;
1652                         if (sk->sk_shutdown & RCV_SHUTDOWN)
1653                                 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
1654                         if (sk->sk_state == SMC_APPCLOSEWAIT1)
1655                                 mask |= EPOLLIN;
1656                         if (smc->conn.urg_state == SMC_URG_VALID)
1657                                 mask |= EPOLLPRI;
1658                 }
1659         }
1660
1661         return mask;
1662 }
1663
1664 static int smc_shutdown(struct socket *sock, int how)
1665 {
1666         struct sock *sk = sock->sk;
1667         struct smc_sock *smc;
1668         int rc = -EINVAL;
1669         int rc1 = 0;
1670
1671         smc = smc_sk(sk);
1672
1673         if ((how < SHUT_RD) || (how > SHUT_RDWR))
1674                 return rc;
1675
1676         lock_sock(sk);
1677
1678         rc = -ENOTCONN;
1679         if ((sk->sk_state != SMC_ACTIVE) &&
1680             (sk->sk_state != SMC_PEERCLOSEWAIT1) &&
1681             (sk->sk_state != SMC_PEERCLOSEWAIT2) &&
1682             (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1683             (sk->sk_state != SMC_APPCLOSEWAIT2) &&
1684             (sk->sk_state != SMC_APPFINCLOSEWAIT))
1685                 goto out;
1686         if (smc->use_fallback) {
1687                 rc = kernel_sock_shutdown(smc->clcsock, how);
1688                 sk->sk_shutdown = smc->clcsock->sk->sk_shutdown;
1689                 if (sk->sk_shutdown == SHUTDOWN_MASK)
1690                         sk->sk_state = SMC_CLOSED;
1691                 goto out;
1692         }
1693         switch (how) {
1694         case SHUT_RDWR:         /* shutdown in both directions */
1695                 rc = smc_close_active(smc);
1696                 break;
1697         case SHUT_WR:
1698                 rc = smc_close_shutdown_write(smc);
1699                 break;
1700         case SHUT_RD:
1701                 rc = 0;
1702                 /* nothing more to do because peer is not involved */
1703                 break;
1704         }
1705         if (smc->clcsock)
1706                 rc1 = kernel_sock_shutdown(smc->clcsock, how);
1707         /* map sock_shutdown_cmd constants to sk_shutdown value range */
1708         sk->sk_shutdown |= how + 1;
1709
1710 out:
1711         release_sock(sk);
1712         return rc ? rc : rc1;
1713 }
1714
1715 static int smc_setsockopt(struct socket *sock, int level, int optname,
1716                           char __user *optval, unsigned int optlen)
1717 {
1718         struct sock *sk = sock->sk;
1719         struct smc_sock *smc;
1720         int val, rc;
1721
1722         smc = smc_sk(sk);
1723
1724         /* generic setsockopts reaching us here always apply to the
1725          * CLC socket
1726          */
1727         rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
1728                                            optval, optlen);
1729         if (smc->clcsock->sk->sk_err) {
1730                 sk->sk_err = smc->clcsock->sk->sk_err;
1731                 sk->sk_error_report(sk);
1732         }
1733
1734         if (optlen < sizeof(int))
1735                 return -EINVAL;
1736         if (get_user(val, (int __user *)optval))
1737                 return -EFAULT;
1738
1739         lock_sock(sk);
1740         if (rc || smc->use_fallback)
1741                 goto out;
1742         switch (optname) {
1743         case TCP_ULP:
1744         case TCP_FASTOPEN:
1745         case TCP_FASTOPEN_CONNECT:
1746         case TCP_FASTOPEN_KEY:
1747         case TCP_FASTOPEN_NO_COOKIE:
1748                 /* option not supported by SMC */
1749                 if (sk->sk_state == SMC_INIT && !smc->connect_nonblock) {
1750                         smc_switch_to_fallback(smc);
1751                         smc->fallback_rsn = SMC_CLC_DECL_OPTUNSUPP;
1752                 } else {
1753                         rc = -EINVAL;
1754                 }
1755                 break;
1756         case TCP_NODELAY:
1757                 if (sk->sk_state != SMC_INIT &&
1758                     sk->sk_state != SMC_LISTEN &&
1759                     sk->sk_state != SMC_CLOSED) {
1760                         if (val)
1761                                 mod_delayed_work(system_wq, &smc->conn.tx_work,
1762                                                  0);
1763                 }
1764                 break;
1765         case TCP_CORK:
1766                 if (sk->sk_state != SMC_INIT &&
1767                     sk->sk_state != SMC_LISTEN &&
1768                     sk->sk_state != SMC_CLOSED) {
1769                         if (!val)
1770                                 mod_delayed_work(system_wq, &smc->conn.tx_work,
1771                                                  0);
1772                 }
1773                 break;
1774         case TCP_DEFER_ACCEPT:
1775                 smc->sockopt_defer_accept = val;
1776                 break;
1777         default:
1778                 break;
1779         }
1780 out:
1781         release_sock(sk);
1782
1783         return rc;
1784 }
1785
1786 static int smc_getsockopt(struct socket *sock, int level, int optname,
1787                           char __user *optval, int __user *optlen)
1788 {
1789         struct smc_sock *smc;
1790
1791         smc = smc_sk(sock->sk);
1792         /* socket options apply to the CLC socket */
1793         return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
1794                                              optval, optlen);
1795 }
1796
1797 static int smc_ioctl(struct socket *sock, unsigned int cmd,
1798                      unsigned long arg)
1799 {
1800         union smc_host_cursor cons, urg;
1801         struct smc_connection *conn;
1802         struct smc_sock *smc;
1803         int answ;
1804
1805         smc = smc_sk(sock->sk);
1806         conn = &smc->conn;
1807         lock_sock(&smc->sk);
1808         if (smc->use_fallback) {
1809                 if (!smc->clcsock) {
1810                         release_sock(&smc->sk);
1811                         return -EBADF;
1812                 }
1813                 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
1814                 release_sock(&smc->sk);
1815                 return answ;
1816         }
1817         switch (cmd) {
1818         case SIOCINQ: /* same as FIONREAD */
1819                 if (smc->sk.sk_state == SMC_LISTEN) {
1820                         release_sock(&smc->sk);
1821                         return -EINVAL;
1822                 }
1823                 if (smc->sk.sk_state == SMC_INIT ||
1824                     smc->sk.sk_state == SMC_CLOSED)
1825                         answ = 0;
1826                 else
1827                         answ = atomic_read(&smc->conn.bytes_to_rcv);
1828                 break;
1829         case SIOCOUTQ:
1830                 /* output queue size (not send + not acked) */
1831                 if (smc->sk.sk_state == SMC_LISTEN) {
1832                         release_sock(&smc->sk);
1833                         return -EINVAL;
1834                 }
1835                 if (smc->sk.sk_state == SMC_INIT ||
1836                     smc->sk.sk_state == SMC_CLOSED)
1837                         answ = 0;
1838                 else
1839                         answ = smc->conn.sndbuf_desc->len -
1840                                         atomic_read(&smc->conn.sndbuf_space);
1841                 break;
1842         case SIOCOUTQNSD:
1843                 /* output queue size (not send only) */
1844                 if (smc->sk.sk_state == SMC_LISTEN) {
1845                         release_sock(&smc->sk);
1846                         return -EINVAL;
1847                 }
1848                 if (smc->sk.sk_state == SMC_INIT ||
1849                     smc->sk.sk_state == SMC_CLOSED)
1850                         answ = 0;
1851                 else
1852                         answ = smc_tx_prepared_sends(&smc->conn);
1853                 break;
1854         case SIOCATMARK:
1855                 if (smc->sk.sk_state == SMC_LISTEN) {
1856                         release_sock(&smc->sk);
1857                         return -EINVAL;
1858                 }
1859                 if (smc->sk.sk_state == SMC_INIT ||
1860                     smc->sk.sk_state == SMC_CLOSED) {
1861                         answ = 0;
1862                 } else {
1863                         smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn);
1864                         smc_curs_copy(&urg, &conn->urg_curs, conn);
1865                         answ = smc_curs_diff(conn->rmb_desc->len,
1866                                              &cons, &urg) == 1;
1867                 }
1868                 break;
1869         default:
1870                 release_sock(&smc->sk);
1871                 return -ENOIOCTLCMD;
1872         }
1873         release_sock(&smc->sk);
1874
1875         return put_user(answ, (int __user *)arg);
1876 }
1877
1878 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
1879                             int offset, size_t size, int flags)
1880 {
1881         struct sock *sk = sock->sk;
1882         struct smc_sock *smc;
1883         int rc = -EPIPE;
1884
1885         smc = smc_sk(sk);
1886         lock_sock(sk);
1887         if (sk->sk_state != SMC_ACTIVE) {
1888                 release_sock(sk);
1889                 goto out;
1890         }
1891         release_sock(sk);
1892         if (smc->use_fallback)
1893                 rc = kernel_sendpage(smc->clcsock, page, offset,
1894                                      size, flags);
1895         else
1896                 rc = sock_no_sendpage(sock, page, offset, size, flags);
1897
1898 out:
1899         return rc;
1900 }
1901
1902 /* Map the affected portions of the rmbe into an spd, note the number of bytes
1903  * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor
1904  * updates till whenever a respective page has been fully processed.
1905  * Note that subsequent recv() calls have to wait till all splice() processing
1906  * completed.
1907  */
1908 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
1909                                struct pipe_inode_info *pipe, size_t len,
1910                                unsigned int flags)
1911 {
1912         struct sock *sk = sock->sk;
1913         struct smc_sock *smc;
1914         int rc = -ENOTCONN;
1915
1916         smc = smc_sk(sk);
1917         lock_sock(sk);
1918         if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
1919                 /* socket was connected before, no more data to read */
1920                 rc = 0;
1921                 goto out;
1922         }
1923         if (sk->sk_state == SMC_INIT ||
1924             sk->sk_state == SMC_LISTEN ||
1925             sk->sk_state == SMC_CLOSED)
1926                 goto out;
1927
1928         if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1929                 rc = 0;
1930                 goto out;
1931         }
1932
1933         if (smc->use_fallback) {
1934                 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
1935                                                     pipe, len, flags);
1936         } else {
1937                 if (*ppos) {
1938                         rc = -ESPIPE;
1939                         goto out;
1940                 }
1941                 if (flags & SPLICE_F_NONBLOCK)
1942                         flags = MSG_DONTWAIT;
1943                 else
1944                         flags = 0;
1945                 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
1946         }
1947 out:
1948         release_sock(sk);
1949
1950         return rc;
1951 }
1952
1953 /* must look like tcp */
1954 static const struct proto_ops smc_sock_ops = {
1955         .family         = PF_SMC,
1956         .owner          = THIS_MODULE,
1957         .release        = smc_release,
1958         .bind           = smc_bind,
1959         .connect        = smc_connect,
1960         .socketpair     = sock_no_socketpair,
1961         .accept         = smc_accept,
1962         .getname        = smc_getname,
1963         .poll           = smc_poll,
1964         .ioctl          = smc_ioctl,
1965         .listen         = smc_listen,
1966         .shutdown       = smc_shutdown,
1967         .setsockopt     = smc_setsockopt,
1968         .getsockopt     = smc_getsockopt,
1969         .sendmsg        = smc_sendmsg,
1970         .recvmsg        = smc_recvmsg,
1971         .mmap           = sock_no_mmap,
1972         .sendpage       = smc_sendpage,
1973         .splice_read    = smc_splice_read,
1974 };
1975
1976 static int smc_create(struct net *net, struct socket *sock, int protocol,
1977                       int kern)
1978 {
1979         int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
1980         struct smc_sock *smc;
1981         struct sock *sk;
1982         int rc;
1983
1984         rc = -ESOCKTNOSUPPORT;
1985         if (sock->type != SOCK_STREAM)
1986                 goto out;
1987
1988         rc = -EPROTONOSUPPORT;
1989         if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
1990                 goto out;
1991
1992         rc = -ENOBUFS;
1993         sock->ops = &smc_sock_ops;
1994         sk = smc_sock_alloc(net, sock, protocol);
1995         if (!sk)
1996                 goto out;
1997
1998         /* create internal TCP socket for CLC handshake and fallback */
1999         smc = smc_sk(sk);
2000         smc->use_fallback = false; /* assume rdma capability first */
2001         smc->fallback_rsn = 0;
2002         rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP,
2003                               &smc->clcsock);
2004         if (rc) {
2005                 sk_common_release(sk);
2006                 goto out;
2007         }
2008         smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE);
2009         smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE);
2010
2011 out:
2012         return rc;
2013 }
2014
2015 static const struct net_proto_family smc_sock_family_ops = {
2016         .family = PF_SMC,
2017         .owner  = THIS_MODULE,
2018         .create = smc_create,
2019 };
2020
2021 unsigned int smc_net_id;
2022
2023 static __net_init int smc_net_init(struct net *net)
2024 {
2025         return smc_pnet_net_init(net);
2026 }
2027
2028 static void __net_exit smc_net_exit(struct net *net)
2029 {
2030         smc_pnet_net_exit(net);
2031 }
2032
2033 static struct pernet_operations smc_net_ops = {
2034         .init = smc_net_init,
2035         .exit = smc_net_exit,
2036         .id   = &smc_net_id,
2037         .size = sizeof(struct smc_net),
2038 };
2039
2040 static int __init smc_init(void)
2041 {
2042         int rc;
2043
2044         rc = register_pernet_subsys(&smc_net_ops);
2045         if (rc)
2046                 return rc;
2047
2048         rc = smc_pnet_init();
2049         if (rc)
2050                 goto out_pernet_subsys;
2051
2052         rc = smc_core_init();
2053         if (rc) {
2054                 pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
2055                 goto out_pnet;
2056         }
2057
2058         rc = smc_llc_init();
2059         if (rc) {
2060                 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
2061                 goto out_core;
2062         }
2063
2064         rc = smc_cdc_init();
2065         if (rc) {
2066                 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
2067                 goto out_core;
2068         }
2069
2070         rc = proto_register(&smc_proto, 1);
2071         if (rc) {
2072                 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
2073                 goto out_core;
2074         }
2075
2076         rc = proto_register(&smc_proto6, 1);
2077         if (rc) {
2078                 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
2079                 goto out_proto;
2080         }
2081
2082         rc = sock_register(&smc_sock_family_ops);
2083         if (rc) {
2084                 pr_err("%s: sock_register fails with %d\n", __func__, rc);
2085                 goto out_proto6;
2086         }
2087         INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
2088         INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
2089
2090         rc = smc_ib_register_client();
2091         if (rc) {
2092                 pr_err("%s: ib_register fails with %d\n", __func__, rc);
2093                 goto out_sock;
2094         }
2095
2096         static_branch_enable(&tcp_have_smc);
2097         return 0;
2098
2099 out_sock:
2100         sock_unregister(PF_SMC);
2101 out_proto6:
2102         proto_unregister(&smc_proto6);
2103 out_proto:
2104         proto_unregister(&smc_proto);
2105 out_core:
2106         smc_core_exit();
2107 out_pnet:
2108         smc_pnet_exit();
2109 out_pernet_subsys:
2110         unregister_pernet_subsys(&smc_net_ops);
2111
2112         return rc;
2113 }
2114
2115 static void __exit smc_exit(void)
2116 {
2117         static_branch_disable(&tcp_have_smc);
2118         sock_unregister(PF_SMC);
2119         smc_core_exit();
2120         smc_ib_unregister_client();
2121         proto_unregister(&smc_proto6);
2122         proto_unregister(&smc_proto);
2123         smc_pnet_exit();
2124         unregister_pernet_subsys(&smc_net_ops);
2125         rcu_barrier();
2126 }
2127
2128 module_init(smc_init);
2129 module_exit(smc_exit);
2130
2131 MODULE_AUTHOR("Ursula Braun <ubraun@linux.vnet.ibm.com>");
2132 MODULE_DESCRIPTION("smc socket address family");
2133 MODULE_LICENSE("GPL");
2134 MODULE_ALIAS_NETPROTO(PF_SMC);