1 // SPDX-License-Identifier: GPL-2.0-only
3 * Shared Memory Communications over RDMA (SMC-R) and RoCE
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
10 * Initial restrictions:
11 * - support for alternate links postponed
13 * Copyright IBM Corp. 2016, 2018
15 * Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
16 * based on prototype from Frank Blaschka
19 #define KMSG_COMPONENT "smc"
20 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
22 #include <linux/module.h>
23 #include <linux/socket.h>
24 #include <linux/workqueue.h>
26 #include <linux/sched/signal.h>
27 #include <linux/if_vlan.h>
28 #include <linux/rcupdate_wait.h>
33 #include <asm/ioctls.h>
35 #include <net/net_namespace.h>
36 #include <net/netns/generic.h>
37 #include "smc_netns.h"
49 #include "smc_close.h"
51 static DEFINE_MUTEX(smc_server_lgr_pending); /* serialize link group
54 static DEFINE_MUTEX(smc_client_lgr_pending); /* serialize link group
58 static void smc_tcp_listen_work(struct work_struct *);
59 static void smc_connect_work(struct work_struct *);
61 static void smc_set_keepalive(struct sock *sk, int val)
63 struct smc_sock *smc = smc_sk(sk);
65 smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val);
68 static struct smc_hashinfo smc_v4_hashinfo = {
69 .lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock),
72 static struct smc_hashinfo smc_v6_hashinfo = {
73 .lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock),
76 int smc_hash_sk(struct sock *sk)
78 struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
79 struct hlist_head *head;
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);
90 EXPORT_SYMBOL_GPL(smc_hash_sk);
92 void smc_unhash_sk(struct sock *sk)
94 struct smc_hashinfo *h = sk->sk_prot->h.smc_hash;
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);
101 EXPORT_SYMBOL_GPL(smc_unhash_sk);
103 struct proto smc_proto = {
105 .owner = THIS_MODULE,
106 .keepalive = smc_set_keepalive,
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,
113 EXPORT_SYMBOL_GPL(smc_proto);
115 struct proto smc_proto6 = {
117 .owner = THIS_MODULE,
118 .keepalive = smc_set_keepalive,
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,
125 EXPORT_SYMBOL_GPL(smc_proto6);
127 static void smc_restore_fallback_changes(struct smc_sock *smc)
129 smc->clcsock->file->private_data = smc->sk.sk_socket;
130 smc->clcsock->file = NULL;
133 static int __smc_release(struct smc_sock *smc)
135 struct sock *sk = &smc->sk;
138 if (!smc->use_fallback) {
139 rc = smc_close_active(smc);
140 sock_set_flag(sk, SOCK_DEAD);
141 sk->sk_shutdown |= SHUTDOWN_MASK;
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);
149 sk->sk_state = SMC_CLOSED;
150 sk->sk_state_change(sk);
151 smc_restore_fallback_changes(smc);
154 sk->sk_prot->unhash(sk);
156 if (sk->sk_state == SMC_CLOSED) {
159 smc_clcsock_release(smc);
162 if (!smc->use_fallback)
163 smc_conn_free(&smc->conn);
169 static int smc_release(struct socket *sock)
171 struct sock *sk = sock->sk;
172 struct smc_sock *smc;
178 sock_hold(sk); /* sock_put below */
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);
186 if (sk->sk_state == SMC_LISTEN)
187 /* smc_close_non_accepted() is called and acquires
188 * sock lock for child sockets again
190 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
194 rc = __smc_release(smc);
201 sock_put(sk); /* sock_hold above */
202 sock_put(sk); /* final sock_put */
207 static void smc_destruct(struct sock *sk)
209 if (sk->sk_state != SMC_CLOSED)
211 if (!sock_flag(sk, SOCK_DEAD))
214 sk_refcnt_debug_dec(sk);
217 static struct sock *smc_sock_alloc(struct net *net, struct socket *sock,
220 struct smc_sock *smc;
224 prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto;
225 sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 0);
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;
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);
247 static int smc_bind(struct socket *sock, struct sockaddr *uaddr,
250 struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
251 struct sock *sk = sock->sk;
252 struct smc_sock *smc;
257 /* replicate tests from inet_bind(), to be safe wrt. future changes */
259 if (addr_len < sizeof(struct sockaddr_in))
263 if (addr->sin_family != AF_INET &&
264 addr->sin_family != AF_INET6 &&
265 addr->sin_family != AF_UNSPEC)
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))
274 /* Check if socket is already active */
276 if (sk->sk_state != SMC_INIT || smc->connect_nonblock)
279 smc->clcsock->sk->sk_reuse = sk->sk_reuse;
280 rc = kernel_bind(smc->clcsock, uaddr, addr_len);
288 static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
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;
303 nsk->sk_flags &= ~mask;
304 nsk->sk_flags |= osk->sk_flags & mask;
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)
325 static void smc_copy_sock_settings_to_clc(struct smc_sock *smc)
327 smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC);
330 #define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \
331 (1UL << SOCK_KEEPOPEN) | \
332 (1UL << SOCK_LINGER) | \
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)
337 smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
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,
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;
350 rmb_desc->wr_reg = 1;
354 /* exchange confirm_rkey msg with peer */
355 if (smc_llc_do_confirm_rkey(link, rmb_desc)) {
356 rmb_desc->regerr = 1;
362 static int smc_clnt_conf_first_link(struct smc_sock *smc)
364 struct net *net = sock_net(smc->clcsock->sk);
365 struct smc_link_group *lgr = smc->conn.lgr;
366 struct smc_link *link;
370 link = &lgr->lnk[SMC_SINGLE_LINK];
371 /* receive CONFIRM LINK request from server over RoCE fabric */
372 rest = wait_for_completion_interruptible_timeout(
374 SMC_LLC_WAIT_FIRST_TIME);
376 struct smc_clc_msg_decline dclc;
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;
383 if (link->llc_confirm_rc)
384 return SMC_CLC_DECL_RMBE_EC;
386 rc = smc_ib_modify_qp_rts(link);
388 return SMC_CLC_DECL_ERR_RDYLNK;
390 smc_wr_remember_qp_attr(link);
392 if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
393 return SMC_CLC_DECL_ERR_REGRMB;
395 /* send CONFIRM LINK response over RoCE fabric */
396 rc = smc_llc_send_confirm_link(link, SMC_LLC_RESP);
398 return SMC_CLC_DECL_TIMEOUT_CL;
400 /* receive ADD LINK request from server over RoCE fabric */
401 rest = wait_for_completion_interruptible_timeout(&link->llc_add,
404 struct smc_clc_msg_decline dclc;
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;
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);
416 return SMC_CLC_DECL_TIMEOUT_AL;
418 smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
423 static void smcr_conn_save_peer_info(struct smc_sock *smc,
424 struct smc_clc_msg_accept_confirm *clc)
426 int bufsize = smc_uncompress_bufsize(clc->rmbe_size);
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);
435 static void smcd_conn_save_peer_info(struct smc_sock *smc,
436 struct smc_clc_msg_accept_confirm *clc)
438 int bufsize = smc_uncompress_bufsize(clc->dmbe_size);
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;
448 static void smc_conn_save_peer_info(struct smc_sock *smc,
449 struct smc_clc_msg_accept_confirm *clc)
451 if (smc->conn.lgr->is_smcd)
452 smcd_conn_save_peer_info(smc, clc);
454 smcr_conn_save_peer_info(smc, clc);
457 static void smc_link_save_peer_info(struct smc_link *link,
458 struct smc_clc_msg_accept_confirm *clc)
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;
467 static void smc_switch_to_fallback(struct smc_sock *smc)
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;
478 /* fall back during connect */
479 static int smc_connect_fallback(struct smc_sock *smc, int reason_code)
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;
490 /* decline and fall back during connect */
491 static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code)
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 */
500 if (reason_code != SMC_CLC_DECL_PEERDECL) {
501 rc = smc_clc_send_decline(smc, reason_code);
503 if (smc->sk.sk_state == SMC_INIT)
504 sock_put(&smc->sk); /* passive closing */
508 return smc_connect_fallback(smc, reason_code);
511 /* abort connecting */
512 static int smc_connect_abort(struct smc_sock *smc, int reason_code,
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);
521 mutex_unlock(&smc_client_lgr_pending);
523 smc_conn_free(&smc->conn);
524 smc->connect_nonblock = 0;
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)
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
536 smc_pnet_find_roce_resource(smc->clcsock->sk, ini);
538 return SMC_CLC_DECL_NOSMCRDEV;
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)
546 /* Find ISM device with same PNETID as connecting interface */
547 smc_pnet_find_ism_resource(smc->clcsock->sk, ini);
549 return SMC_CLC_DECL_NOSMCDDEV;
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)
557 if (ini->vlan_id && smc_ism_get_vlan(ini->ism_dev, ini->vlan_id))
558 return SMC_CLC_DECL_ISMVLANERR;
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.
565 static int smc_connect_ism_vlan_cleanup(struct smc_sock *smc, bool is_smcd,
566 struct smc_init_info *ini)
570 if (ini->vlan_id && smc_ism_put_vlan(ini->ism_dev, ini->vlan_id))
571 return SMC_CLC_DECL_CNFERR;
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)
582 /* do inband token exchange */
583 rc = smc_clc_send_proposal(smc, smc_type, ini);
586 /* receive SMC Accept CLC message */
587 return smc_clc_wait_msg(smc, aclc, sizeof(*aclc), SMC_CLC_ACCEPT,
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)
596 struct smc_link *link;
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;
604 mutex_lock(&smc_client_lgr_pending);
605 reason_code = smc_conn_create(smc, ini);
607 mutex_unlock(&smc_client_lgr_pending);
610 link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK];
612 smc_conn_save_peer_info(smc, aclc);
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);
619 if (ini->cln_first_contact == SMC_FIRST_CONTACT)
620 smc_link_save_peer_info(link, aclc);
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);
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);
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);
638 smc_rmb_sync_sg_for_device(&smc->conn);
640 reason_code = smc_clc_send_confirm(smc);
642 return smc_connect_abort(smc, reason_code,
643 ini->cln_first_contact);
647 if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
648 /* QP confirmation over RoCE fabric */
649 reason_code = smc_clnt_conf_first_link(smc);
651 return smc_connect_abort(smc, reason_code,
652 ini->cln_first_contact);
654 mutex_unlock(&smc_client_lgr_pending);
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;
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)
672 ini->ism_gid = aclc->gid;
673 ini->srv_first_contact = aclc->hdr.flag;
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);
679 mutex_unlock(&smc_server_lgr_pending);
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);
688 smc_conn_save_peer_info(smc, aclc);
693 rc = smc_clc_send_confirm(smc);
695 return smc_connect_abort(smc, rc, ini->cln_first_contact);
696 mutex_unlock(&smc_server_lgr_pending);
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;
706 /* perform steps before actually connecting */
707 static int __smc_connect(struct smc_sock *smc)
709 bool ism_supported = false, rdma_supported = false;
710 struct smc_clc_msg_accept_confirm aclc;
711 struct smc_init_info ini = {0};
715 if (smc->use_fallback)
716 return smc_connect_fallback(smc, smc->fallback_rsn);
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);
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);
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);
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;
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;
744 smc_type = SMC_TYPE_B; /* both */
746 smc_type = SMC_TYPE_R; /* only RDMA */
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);
753 /* perform CLC handshake */
754 rc = smc_connect_clc(smc, smc_type, &aclc, &ini);
756 smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
757 return smc_connect_decline_fallback(smc, rc);
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);
766 rc = SMC_CLC_DECL_MODEUNSUPP;
768 smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
769 return smc_connect_decline_fallback(smc, rc);
772 smc_connect_ism_vlan_cleanup(smc, ism_supported, &ini);
776 static void smc_connect_work(struct work_struct *work)
778 struct smc_sock *smc = container_of(work, struct smc_sock,
780 long timeo = smc->sk.sk_sndtimeo;
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)))
796 release_sock(smc->clcsock->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 */
808 rc = __smc_connect(smc);
810 smc->sk.sk_err = -rc;
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);
821 release_sock(&smc->sk);
824 static int smc_connect(struct socket *sock, struct sockaddr *addr,
827 struct sock *sk = sock->sk;
828 struct smc_sock *smc;
833 /* separate smc parameter checking to be safe */
834 if (alen < sizeof(addr->sa_family))
836 if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)
840 switch (sk->sk_state) {
851 smc_copy_sock_settings_to_clc(smc);
852 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
853 if (smc->connect_nonblock) {
857 rc = kernel_connect(smc->clcsock, addr, alen, flags);
858 if (rc && rc != -EINPROGRESS)
861 sock_hold(&smc->sk); /* sock put in passive closing */
862 if (smc->use_fallback)
864 if (flags & O_NONBLOCK) {
865 if (schedule_work(&smc->connect_work))
866 smc->connect_nonblock = 1;
869 rc = __smc_connect(smc);
873 rc = 0; /* success cases including fallback */
882 static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc)
884 struct socket *new_clcsock = NULL;
885 struct sock *lsk = &lsmc->sk;
890 new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol);
893 lsk->sk_err = ENOMEM;
898 *new_smc = smc_sk(new_sk);
900 mutex_lock(&lsmc->clcsock_release_lock);
902 rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0);
903 mutex_unlock(&lsmc->clcsock_release_lock);
907 if (rc < 0 || lsk->sk_state == SMC_CLOSED) {
908 new_sk->sk_prot->unhash(new_sk);
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 */
918 (*new_smc)->clcsock = new_clcsock;
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
926 static void smc_accept_enqueue(struct sock *parent, struct sock *sk)
928 struct smc_sock *par = smc_sk(parent);
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);
937 /* remove a socket from the accept queue of its parental listening socket */
938 static void smc_accept_unlink(struct sock *sk)
940 struct smc_sock *par = smc_sk(sk)->listen_smc;
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 */
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
952 struct sock *smc_accept_dequeue(struct sock *parent,
953 struct socket *new_sock)
955 struct smc_sock *isk, *n;
958 list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) {
959 new_sk = (struct sock *)isk;
961 smc_accept_unlink(new_sk);
962 if (new_sk->sk_state == SMC_CLOSED) {
963 new_sk->sk_prot->unhash(new_sk);
965 sock_release(isk->clcsock);
968 sock_put(new_sk); /* final */
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;
983 /* clean up for a created but never accepted sock */
984 void smc_close_non_accepted(struct sock *sk)
986 struct smc_sock *smc = smc_sk(sk);
988 sock_hold(sk); /* sock_put below */
990 if (!sk->sk_lingertime)
991 /* wait for peer closing */
992 sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT;
995 sock_put(sk); /* sock_hold above */
996 sock_put(sk); /* final sock_put */
999 static int smc_serv_conf_first_link(struct smc_sock *smc)
1001 struct net *net = sock_net(smc->clcsock->sk);
1002 struct smc_link_group *lgr = smc->conn.lgr;
1003 struct smc_link *link;
1007 link = &lgr->lnk[SMC_SINGLE_LINK];
1009 if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
1010 return SMC_CLC_DECL_ERR_REGRMB;
1012 /* send CONFIRM LINK request to client over the RoCE fabric */
1013 rc = smc_llc_send_confirm_link(link, SMC_LLC_REQ);
1015 return SMC_CLC_DECL_TIMEOUT_CL;
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);
1022 struct smc_clc_msg_decline dclc;
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;
1029 if (link->llc_confirm_resp_rc)
1030 return SMC_CLC_DECL_RMBE_EC;
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);
1037 return SMC_CLC_DECL_TIMEOUT_AL;
1039 /* receive ADD LINK response from client over the RoCE fabric */
1040 rest = wait_for_completion_interruptible_timeout(&link->llc_add_resp,
1043 struct smc_clc_msg_decline dclc;
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;
1050 smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time);
1055 /* listen worker: finish */
1056 static void smc_listen_out(struct smc_sock *new_smc)
1058 struct smc_sock *lsmc = new_smc->listen_smc;
1059 struct sock *newsmcsk = &new_smc->sk;
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);
1069 /* Wake up accept */
1070 lsmc->sk.sk_data_ready(&lsmc->sk);
1071 sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */
1074 /* listen worker: finish in state connected */
1075 static void smc_listen_out_connected(struct smc_sock *new_smc)
1077 struct sock *newsmcsk = &new_smc->sk;
1079 sk_refcnt_debug_inc(newsmcsk);
1080 if (newsmcsk->sk_state == SMC_INIT)
1081 newsmcsk->sk_state = SMC_ACTIVE;
1083 smc_listen_out(new_smc);
1086 /* listen worker: finish in error state */
1087 static void smc_listen_out_err(struct smc_sock *new_smc)
1089 struct sock *newsmcsk = &new_smc->sk;
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);
1096 smc_listen_out(new_smc);
1099 /* listen worker: decline and fall back if possible */
1100 static void smc_listen_decline(struct smc_sock *new_smc, int reason_code,
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);
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);
1119 smc_listen_out_connected(new_smc);
1122 /* listen worker: check prefixes */
1123 static int smc_listen_prfx_check(struct smc_sock *new_smc,
1124 struct smc_clc_msg_proposal *pclc)
1126 struct smc_clc_msg_proposal_prefix *pclc_prfx;
1127 struct socket *newclcsock = new_smc->clcsock;
1129 pclc_prfx = smc_clc_proposal_get_prefix(pclc);
1130 if (smc_clc_prfx_match(newclcsock, pclc_prfx))
1131 return SMC_CLC_DECL_DIFFPREFIX;
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)
1142 /* allocate connection / link group */
1143 rc = smc_conn_create(new_smc, ini);
1147 /* create send buffer and rmb */
1148 if (smc_buf_create(new_smc, false))
1149 return SMC_CLC_DECL_MEM;
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)
1159 struct smc_clc_msg_smcd *pclc_smcd;
1162 pclc_smcd = smc_get_clc_msg_smcd(pclc);
1163 ini->ism_gid = pclc_smcd->gid;
1164 rc = smc_conn_create(new_smc, ini);
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;
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;
1189 /* listen worker: register buffers */
1190 static int smc_listen_rdma_reg(struct smc_sock *new_smc, int local_contact)
1192 struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
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;
1198 smc_rmb_sync_sg_for_device(&new_smc->conn);
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,
1208 struct smc_link *link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK];
1209 int reason_code = 0;
1211 if (local_contact == SMC_FIRST_CONTACT)
1212 smc_link_save_peer_info(link, cclc);
1214 if (smc_rmb_rtoken_handling(&new_smc->conn, cclc)) {
1215 reason_code = SMC_CLC_DECL_ERR_RTOK;
1219 if (local_contact == SMC_FIRST_CONTACT) {
1220 if (smc_ib_ready_link(link)) {
1221 reason_code = SMC_CLC_DECL_ERR_RDYLNK;
1224 /* QP confirmation over RoCE fabric */
1225 reason_code = smc_serv_conf_first_link(new_smc);
1232 smc_listen_decline(new_smc, reason_code, local_contact);
1236 /* setup for RDMA connection of server */
1237 static void smc_listen_work(struct work_struct *work)
1239 struct smc_sock *new_smc = container_of(work, struct smc_sock,
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];
1249 if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN)
1250 return smc_listen_out_err(new_smc);
1252 if (new_smc->use_fallback) {
1253 smc_listen_out_connected(new_smc);
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);
1265 /* do inband token exchange -
1266 * wait for and receive SMC Proposal CLC message
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);
1274 /* IPSec connections opt out of SMC-R optimizations */
1275 if (using_ipsec(new_smc)) {
1276 rc = SMC_CLC_DECL_IPSEC;
1280 /* check for matching IP prefix and subnet length */
1281 rc = smc_listen_prfx_check(new_smc, pclc);
1285 /* get vlan id from IP device */
1286 if (smc_vlan_by_tcpsk(new_smc->clcsock, &ini)) {
1287 rc = SMC_CLC_DECL_GETVLANERR;
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);
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);
1301 rc = smc_listen_ism_init(new_smc, pclc, &ini);
1303 ism_supported = true;
1304 else if (pclc->hdr.path == SMC_TYPE_D)
1305 goto out_unlock; /* skip RDMA and decline */
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;
1313 ini.ib_lcl = &pclc->lcl;
1314 rc = smc_find_rdma_device(new_smc, &ini);
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;
1322 rc = smc_listen_rdma_init(new_smc, &ini);
1325 rc = smc_listen_rdma_reg(new_smc, ini.cln_first_contact);
1330 /* send SMC Accept CLC message */
1331 rc = smc_clc_send_accept(new_smc, ini.cln_first_contact);
1335 /* SMC-D does not need this lock any more */
1337 mutex_unlock(&smc_server_lgr_pending);
1339 /* receive SMC Confirm CLC message */
1340 rc = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc),
1341 SMC_CLC_CONFIRM, CLC_WAIT_TIME);
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);
1356 smc_conn_save_peer_info(new_smc, &cclc);
1357 smc_listen_out_connected(new_smc);
1361 mutex_unlock(&smc_server_lgr_pending);
1363 smc_listen_decline(new_smc, rc, ini.cln_first_contact);
1366 static void smc_tcp_listen_work(struct work_struct *work)
1368 struct smc_sock *lsmc = container_of(work, struct smc_sock,
1370 struct sock *lsk = &lsmc->sk;
1371 struct smc_sock *new_smc;
1375 while (lsk->sk_state == SMC_LISTEN) {
1376 rc = smc_clcsock_accept(lsmc, &new_smc);
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);
1397 sock_put(&lsmc->sk); /* sock_hold in smc_listen */
1400 static int smc_listen(struct socket *sock, int backlog)
1402 struct sock *sk = sock->sk;
1403 struct smc_sock *smc;
1410 if ((sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) ||
1411 smc->connect_nonblock)
1415 if (sk->sk_state == SMC_LISTEN) {
1416 sk->sk_max_ack_backlog = backlog;
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
1422 smc_copy_sock_settings_to_clc(smc);
1423 if (!smc->use_fallback)
1424 tcp_sk(smc->clcsock->sk)->syn_smc = 1;
1426 rc = kernel_listen(smc->clcsock, backlog);
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))
1441 static int smc_accept(struct socket *sock, struct socket *new_sock,
1442 int flags, bool kern)
1444 struct sock *sk = sock->sk, *nsk;
1445 DECLARE_WAITQUEUE(wait, current);
1446 struct smc_sock *lsmc;
1451 sock_hold(sk); /* sock_put below */
1454 if (lsmc->sk.sk_state != SMC_LISTEN) {
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);
1470 timeo = schedule_timeout(timeo);
1471 /* wakeup by sk_data_ready in smc_listen_work() */
1472 sched_annotate_sleep();
1474 if (signal_pending(current)) {
1475 rc = sock_intr_errno(timeo);
1479 set_current_state(TASK_RUNNING);
1480 remove_wait_queue(sk_sleep(sk), &wait);
1483 rc = sock_error(nsk);
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 *
1492 if (smc_sk(nsk)->use_fallback) {
1493 struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
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)) {
1501 smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available);
1507 sock_put(sk); /* sock_hold above */
1511 static int smc_getname(struct socket *sock, struct sockaddr *addr,
1514 struct smc_sock *smc;
1516 if (peer && (sock->sk->sk_state != SMC_ACTIVE) &&
1517 (sock->sk->sk_state != SMC_APPCLOSEWAIT1))
1520 smc = smc_sk(sock->sk);
1522 return smc->clcsock->ops->getname(smc->clcsock, addr, peer);
1525 static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1527 struct sock *sk = sock->sk;
1528 struct smc_sock *smc;
1533 if ((sk->sk_state != SMC_ACTIVE) &&
1534 (sk->sk_state != SMC_APPCLOSEWAIT1) &&
1535 (sk->sk_state != SMC_INIT))
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;
1548 if (smc->use_fallback)
1549 rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len);
1551 rc = smc_tx_sendmsg(smc, msg, len);
1557 static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1560 struct sock *sk = sock->sk;
1561 struct smc_sock *smc;
1566 if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
1567 /* socket was connected before, no more data to read */
1571 if ((sk->sk_state == SMC_INIT) ||
1572 (sk->sk_state == SMC_LISTEN) ||
1573 (sk->sk_state == SMC_CLOSED))
1576 if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1581 if (smc->use_fallback) {
1582 rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags);
1584 msg->msg_namelen = 0;
1585 rc = smc_rx_recvmsg(smc, msg, NULL, len, flags);
1593 static __poll_t smc_accept_poll(struct sock *parent)
1595 struct smc_sock *isk = smc_sk(parent);
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);
1606 static __poll_t smc_poll(struct file *file, struct socket *sock,
1609 struct sock *sk = sock->sk;
1610 struct smc_sock *smc;
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;
1622 if (sk->sk_state != SMC_CLOSED)
1623 sock_poll_wait(file, sock, wait);
1626 if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
1627 (sk->sk_state == SMC_CLOSED))
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,
1635 sk->sk_err = smc->clcsock->sk->sk_err;
1637 if ((sk->sk_state != SMC_INIT &&
1638 atomic_read(&smc->conn.sndbuf_space)) ||
1639 sk->sk_shutdown & SEND_SHUTDOWN) {
1640 mask |= EPOLLOUT | EPOLLWRNORM;
1642 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1643 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
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)
1651 if (smc->conn.urg_state == SMC_URG_VALID)
1659 static int smc_shutdown(struct socket *sock, int how)
1661 struct sock *sk = sock->sk;
1662 struct smc_sock *smc;
1668 if ((how < SHUT_RD) || (how > SHUT_RDWR))
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))
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;
1689 case SHUT_RDWR: /* shutdown in both directions */
1690 rc = smc_close_active(smc);
1693 rc = smc_close_shutdown_write(smc);
1697 /* nothing more to do because peer is not involved */
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;
1707 return rc ? rc : rc1;
1710 static int smc_setsockopt(struct socket *sock, int level, int optname,
1711 char __user *optval, unsigned int optlen)
1713 struct sock *sk = sock->sk;
1714 struct smc_sock *smc;
1719 /* generic setsockopts reaching us here always apply to the
1722 rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname,
1724 if (smc->clcsock->sk->sk_err) {
1725 sk->sk_err = smc->clcsock->sk->sk_err;
1726 sk->sk_error_report(sk);
1729 if (optlen < sizeof(int))
1731 if (get_user(val, (int __user *)optval))
1735 if (rc || smc->use_fallback)
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;
1752 if (sk->sk_state != SMC_INIT &&
1753 sk->sk_state != SMC_LISTEN &&
1754 sk->sk_state != SMC_CLOSED) {
1756 mod_delayed_work(system_wq, &smc->conn.tx_work,
1761 if (sk->sk_state != SMC_INIT &&
1762 sk->sk_state != SMC_LISTEN &&
1763 sk->sk_state != SMC_CLOSED) {
1765 mod_delayed_work(system_wq, &smc->conn.tx_work,
1769 case TCP_DEFER_ACCEPT:
1770 smc->sockopt_defer_accept = val;
1781 static int smc_getsockopt(struct socket *sock, int level, int optname,
1782 char __user *optval, int __user *optlen)
1784 struct smc_sock *smc;
1786 smc = smc_sk(sock->sk);
1787 /* socket options apply to the CLC socket */
1788 return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname,
1792 static int smc_ioctl(struct socket *sock, unsigned int cmd,
1795 union smc_host_cursor cons, urg;
1796 struct smc_connection *conn;
1797 struct smc_sock *smc;
1800 smc = smc_sk(sock->sk);
1802 lock_sock(&smc->sk);
1803 if (smc->use_fallback) {
1804 if (!smc->clcsock) {
1805 release_sock(&smc->sk);
1808 answ = smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg);
1809 release_sock(&smc->sk);
1813 case SIOCINQ: /* same as FIONREAD */
1814 if (smc->sk.sk_state == SMC_LISTEN) {
1815 release_sock(&smc->sk);
1818 if (smc->sk.sk_state == SMC_INIT ||
1819 smc->sk.sk_state == SMC_CLOSED)
1822 answ = atomic_read(&smc->conn.bytes_to_rcv);
1825 /* output queue size (not send + not acked) */
1826 if (smc->sk.sk_state == SMC_LISTEN) {
1827 release_sock(&smc->sk);
1830 if (smc->sk.sk_state == SMC_INIT ||
1831 smc->sk.sk_state == SMC_CLOSED)
1834 answ = smc->conn.sndbuf_desc->len -
1835 atomic_read(&smc->conn.sndbuf_space);
1838 /* output queue size (not send only) */
1839 if (smc->sk.sk_state == SMC_LISTEN) {
1840 release_sock(&smc->sk);
1843 if (smc->sk.sk_state == SMC_INIT ||
1844 smc->sk.sk_state == SMC_CLOSED)
1847 answ = smc_tx_prepared_sends(&smc->conn);
1850 if (smc->sk.sk_state == SMC_LISTEN) {
1851 release_sock(&smc->sk);
1854 if (smc->sk.sk_state == SMC_INIT ||
1855 smc->sk.sk_state == SMC_CLOSED) {
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,
1865 release_sock(&smc->sk);
1866 return -ENOIOCTLCMD;
1868 release_sock(&smc->sk);
1870 return put_user(answ, (int __user *)arg);
1873 static ssize_t smc_sendpage(struct socket *sock, struct page *page,
1874 int offset, size_t size, int flags)
1876 struct sock *sk = sock->sk;
1877 struct smc_sock *smc;
1882 if (sk->sk_state != SMC_ACTIVE) {
1887 if (smc->use_fallback)
1888 rc = kernel_sendpage(smc->clcsock, page, offset,
1891 rc = sock_no_sendpage(sock, page, offset, size, flags);
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
1903 static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos,
1904 struct pipe_inode_info *pipe, size_t len,
1907 struct sock *sk = sock->sk;
1908 struct smc_sock *smc;
1913 if (sk->sk_state == SMC_CLOSED && (sk->sk_shutdown & RCV_SHUTDOWN)) {
1914 /* socket was connected before, no more data to read */
1918 if (sk->sk_state == SMC_INIT ||
1919 sk->sk_state == SMC_LISTEN ||
1920 sk->sk_state == SMC_CLOSED)
1923 if (sk->sk_state == SMC_PEERFINCLOSEWAIT) {
1928 if (smc->use_fallback) {
1929 rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos,
1936 if (flags & SPLICE_F_NONBLOCK)
1937 flags = MSG_DONTWAIT;
1940 rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags);
1948 /* must look like tcp */
1949 static const struct proto_ops smc_sock_ops = {
1951 .owner = THIS_MODULE,
1952 .release = smc_release,
1954 .connect = smc_connect,
1955 .socketpair = sock_no_socketpair,
1956 .accept = smc_accept,
1957 .getname = smc_getname,
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,
1971 static int smc_create(struct net *net, struct socket *sock, int protocol,
1974 int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET;
1975 struct smc_sock *smc;
1979 rc = -ESOCKTNOSUPPORT;
1980 if (sock->type != SOCK_STREAM)
1983 rc = -EPROTONOSUPPORT;
1984 if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6)
1988 sock->ops = &smc_sock_ops;
1989 sk = smc_sock_alloc(net, sock, protocol);
1993 /* create internal TCP socket for CLC handshake and fallback */
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,
2000 sk_common_release(sk);
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);
2010 static const struct net_proto_family smc_sock_family_ops = {
2012 .owner = THIS_MODULE,
2013 .create = smc_create,
2016 unsigned int smc_net_id;
2018 static __net_init int smc_net_init(struct net *net)
2020 return smc_pnet_net_init(net);
2023 static void __net_exit smc_net_exit(struct net *net)
2025 smc_pnet_net_exit(net);
2028 static struct pernet_operations smc_net_ops = {
2029 .init = smc_net_init,
2030 .exit = smc_net_exit,
2032 .size = sizeof(struct smc_net),
2035 static int __init smc_init(void)
2039 rc = register_pernet_subsys(&smc_net_ops);
2043 rc = smc_pnet_init();
2045 goto out_pernet_subsys;
2047 rc = smc_core_init();
2049 pr_err("%s: smc_core_init fails with %d\n", __func__, rc);
2053 rc = smc_llc_init();
2055 pr_err("%s: smc_llc_init fails with %d\n", __func__, rc);
2059 rc = smc_cdc_init();
2061 pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc);
2065 rc = proto_register(&smc_proto, 1);
2067 pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc);
2071 rc = proto_register(&smc_proto6, 1);
2073 pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc);
2077 rc = sock_register(&smc_sock_family_ops);
2079 pr_err("%s: sock_register fails with %d\n", __func__, rc);
2082 INIT_HLIST_HEAD(&smc_v4_hashinfo.ht);
2083 INIT_HLIST_HEAD(&smc_v6_hashinfo.ht);
2085 rc = smc_ib_register_client();
2087 pr_err("%s: ib_register fails with %d\n", __func__, rc);
2091 static_branch_enable(&tcp_have_smc);
2095 sock_unregister(PF_SMC);
2097 proto_unregister(&smc_proto6);
2099 proto_unregister(&smc_proto);
2105 unregister_pernet_subsys(&smc_net_ops);
2110 static void __exit smc_exit(void)
2112 static_branch_disable(&tcp_have_smc);
2113 sock_unregister(PF_SMC);
2115 smc_ib_unregister_client();
2116 proto_unregister(&smc_proto6);
2117 proto_unregister(&smc_proto);
2119 unregister_pernet_subsys(&smc_net_ops);
2123 module_init(smc_init);
2124 module_exit(smc_exit);
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);