1 // SPDX-License-Identifier: GPL-2.0
3 * Shared Memory Communications over RDMA (SMC-R) and RoCE
5 * Basic Transport Functions exploiting Infiniband API
7 * Copyright IBM Corp. 2016
9 * Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
12 #include <linux/socket.h>
13 #include <linux/if_vlan.h>
14 #include <linux/random.h>
15 #include <linux/workqueue.h>
16 #include <linux/wait.h>
17 #include <linux/reboot.h>
20 #include <rdma/ib_verbs.h>
21 #include <rdma/ib_cache.h>
30 #include "smc_close.h"
33 #define SMC_LGR_NUM_INCR 256
34 #define SMC_LGR_FREE_DELAY_SERV (600 * HZ)
35 #define SMC_LGR_FREE_DELAY_CLNT (SMC_LGR_FREE_DELAY_SERV + 10 * HZ)
36 #define SMC_LGR_FREE_DELAY_FAST (8 * HZ)
38 static struct smc_lgr_list smc_lgr_list = { /* established link groups */
39 .lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
40 .list = LIST_HEAD_INIT(smc_lgr_list.list),
44 static atomic_t lgr_cnt = ATOMIC_INIT(0); /* number of existing link groups */
45 static DECLARE_WAIT_QUEUE_HEAD(lgrs_deleted);
47 struct smc_ib_up_work {
48 struct work_struct work;
49 struct smc_link_group *lgr;
50 struct smc_ib_device *smcibdev;
54 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
55 struct smc_buf_desc *buf_desc);
56 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft);
58 static void smc_link_up_work(struct work_struct *work);
59 static void smc_link_down_work(struct work_struct *work);
61 /* return head of link group list and its lock for a given link group */
62 static inline struct list_head *smc_lgr_list_head(struct smc_link_group *lgr,
63 spinlock_t **lgr_lock)
66 *lgr_lock = &lgr->smcd->lgr_lock;
67 return &lgr->smcd->lgr_list;
70 *lgr_lock = &smc_lgr_list.lock;
71 return &smc_lgr_list.list;
74 static void smc_lgr_schedule_free_work(struct smc_link_group *lgr)
76 /* client link group creation always follows the server link group
77 * creation. For client use a somewhat higher removal delay time,
78 * otherwise there is a risk of out-of-sync link groups.
80 if (!lgr->freeing && !lgr->freefast) {
81 mod_delayed_work(system_wq, &lgr->free_work,
82 (!lgr->is_smcd && lgr->role == SMC_CLNT) ?
83 SMC_LGR_FREE_DELAY_CLNT :
84 SMC_LGR_FREE_DELAY_SERV);
88 void smc_lgr_schedule_free_work_fast(struct smc_link_group *lgr)
90 if (!lgr->freeing && !lgr->freefast) {
92 mod_delayed_work(system_wq, &lgr->free_work,
93 SMC_LGR_FREE_DELAY_FAST);
97 /* Register connection's alert token in our lookup structure.
98 * To use rbtrees we have to implement our own insert core.
99 * Requires @conns_lock
100 * @smc connection to register
101 * Returns 0 on success, != otherwise.
103 static void smc_lgr_add_alert_token(struct smc_connection *conn)
105 struct rb_node **link, *parent = NULL;
106 u32 token = conn->alert_token_local;
108 link = &conn->lgr->conns_all.rb_node;
110 struct smc_connection *cur = rb_entry(*link,
111 struct smc_connection, alert_node);
114 if (cur->alert_token_local > token)
115 link = &parent->rb_left;
117 link = &parent->rb_right;
119 /* Put the new node there */
120 rb_link_node(&conn->alert_node, parent, link);
121 rb_insert_color(&conn->alert_node, &conn->lgr->conns_all);
124 /* assign an SMC-R link to the connection */
125 static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first)
127 enum smc_link_state expected = first ? SMC_LNK_ACTIVATING :
131 /* do link balancing */
132 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
133 struct smc_link *lnk = &conn->lgr->lnk[i];
135 if (lnk->state != expected || lnk->link_is_asym)
137 if (conn->lgr->role == SMC_CLNT) {
138 conn->lnk = lnk; /* temporary, SMC server assigns link*/
141 if (conn->lgr->conns_num % 2) {
142 for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) {
143 struct smc_link *lnk2;
145 lnk2 = &conn->lgr->lnk[j];
146 if (lnk2->state == expected &&
147 !lnk2->link_is_asym) {
158 return SMC_CLC_DECL_NOACTLINK;
162 /* Register connection in link group by assigning an alert token
163 * registered in a search tree.
164 * Requires @conns_lock
165 * Note that '0' is a reserved value and not assigned.
167 static int smc_lgr_register_conn(struct smc_connection *conn, bool first)
169 struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
170 static atomic_t nexttoken = ATOMIC_INIT(0);
173 if (!conn->lgr->is_smcd) {
174 rc = smcr_lgr_conn_assign_link(conn, first);
178 /* find a new alert_token_local value not yet used by some connection
181 sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */
182 while (!conn->alert_token_local) {
183 conn->alert_token_local = atomic_inc_return(&nexttoken);
184 if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr))
185 conn->alert_token_local = 0;
187 smc_lgr_add_alert_token(conn);
188 conn->lgr->conns_num++;
192 /* Unregister connection and reset the alert token of the given connection<
194 static void __smc_lgr_unregister_conn(struct smc_connection *conn)
196 struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
197 struct smc_link_group *lgr = conn->lgr;
199 rb_erase(&conn->alert_node, &lgr->conns_all);
201 conn->alert_token_local = 0;
202 sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
205 /* Unregister connection from lgr
207 static void smc_lgr_unregister_conn(struct smc_connection *conn)
209 struct smc_link_group *lgr = conn->lgr;
213 write_lock_bh(&lgr->conns_lock);
214 if (conn->alert_token_local) {
215 __smc_lgr_unregister_conn(conn);
217 write_unlock_bh(&lgr->conns_lock);
221 void smc_lgr_cleanup_early(struct smc_connection *conn)
223 struct smc_link_group *lgr = conn->lgr;
224 struct list_head *lgr_list;
225 spinlock_t *lgr_lock;
231 lgr_list = smc_lgr_list_head(lgr, &lgr_lock);
232 spin_lock_bh(lgr_lock);
233 /* do not use this link group for new connections */
234 if (!list_empty(lgr_list))
235 list_del_init(lgr_list);
236 spin_unlock_bh(lgr_lock);
237 smc_lgr_schedule_free_work_fast(lgr);
240 static void smcr_lgr_link_deactivate_all(struct smc_link_group *lgr)
244 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
245 struct smc_link *lnk = &lgr->lnk[i];
247 if (smc_link_usable(lnk))
248 lnk->state = SMC_LNK_INACTIVE;
250 wake_up_interruptible_all(&lgr->llc_waiter);
253 static void smc_lgr_free(struct smc_link_group *lgr);
255 static void smc_lgr_free_work(struct work_struct *work)
257 struct smc_link_group *lgr = container_of(to_delayed_work(work),
258 struct smc_link_group,
260 spinlock_t *lgr_lock;
263 smc_lgr_list_head(lgr, &lgr_lock);
264 spin_lock_bh(lgr_lock);
266 spin_unlock_bh(lgr_lock);
269 read_lock_bh(&lgr->conns_lock);
270 conns = RB_EMPTY_ROOT(&lgr->conns_all);
271 read_unlock_bh(&lgr->conns_lock);
272 if (!conns) { /* number of lgr connections is no longer zero */
273 spin_unlock_bh(lgr_lock);
276 list_del_init(&lgr->list); /* remove from smc_lgr_list */
277 lgr->freeing = 1; /* this instance does the freeing, no new schedule */
278 spin_unlock_bh(lgr_lock);
279 cancel_delayed_work(&lgr->free_work);
281 if (!lgr->is_smcd && !lgr->terminating)
282 smc_llc_send_link_delete_all(lgr, true,
283 SMC_LLC_DEL_PROG_INIT_TERM);
284 if (lgr->is_smcd && !lgr->terminating)
285 smc_ism_signal_shutdown(lgr);
287 smcr_lgr_link_deactivate_all(lgr);
291 static void smc_lgr_terminate_work(struct work_struct *work)
293 struct smc_link_group *lgr = container_of(work, struct smc_link_group,
296 __smc_lgr_terminate(lgr, true);
299 /* return next unique link id for the lgr */
300 static u8 smcr_next_link_id(struct smc_link_group *lgr)
306 link_id = ++lgr->next_link_id;
307 if (!link_id) /* skip zero as link_id */
308 link_id = ++lgr->next_link_id;
309 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
310 if (smc_link_usable(&lgr->lnk[i]) &&
311 lgr->lnk[i].link_id == link_id)
319 int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
320 u8 link_idx, struct smc_init_info *ini)
325 get_device(&ini->ib_dev->ibdev->dev);
326 atomic_inc(&ini->ib_dev->lnk_cnt);
327 lnk->state = SMC_LNK_ACTIVATING;
328 lnk->link_id = smcr_next_link_id(lgr);
330 lnk->link_idx = link_idx;
331 lnk->smcibdev = ini->ib_dev;
332 lnk->ibport = ini->ib_port;
333 lnk->path_mtu = ini->ib_dev->pattr[ini->ib_port - 1].active_mtu;
334 smc_llc_link_set_uid(lnk);
335 INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
336 if (!ini->ib_dev->initialized) {
337 rc = (int)smc_ib_setup_per_ibdev(ini->ib_dev);
341 get_random_bytes(rndvec, sizeof(rndvec));
342 lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) +
344 rc = smc_ib_determine_gid(lnk->smcibdev, lnk->ibport,
345 ini->vlan_id, lnk->gid, &lnk->sgid_index);
348 rc = smc_llc_link_init(lnk);
351 rc = smc_wr_alloc_link_mem(lnk);
354 rc = smc_ib_create_protection_domain(lnk);
357 rc = smc_ib_create_queue_pair(lnk);
360 rc = smc_wr_create_link(lnk);
366 smc_ib_destroy_queue_pair(lnk);
368 smc_ib_dealloc_protection_domain(lnk);
370 smc_wr_free_link_mem(lnk);
372 smc_llc_link_clear(lnk, false);
374 put_device(&ini->ib_dev->ibdev->dev);
375 memset(lnk, 0, sizeof(struct smc_link));
376 lnk->state = SMC_LNK_UNUSED;
377 if (!atomic_dec_return(&ini->ib_dev->lnk_cnt))
378 wake_up(&ini->ib_dev->lnks_deleted);
382 /* create a new SMC link group */
383 static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
385 struct smc_link_group *lgr;
386 struct list_head *lgr_list;
387 struct smc_link *lnk;
388 spinlock_t *lgr_lock;
393 if (ini->is_smcd && ini->vlan_id) {
394 if (smc_ism_get_vlan(ini->ism_dev, ini->vlan_id)) {
395 rc = SMC_CLC_DECL_ISMVLANERR;
400 lgr = kzalloc(sizeof(*lgr), GFP_KERNEL);
402 rc = SMC_CLC_DECL_MEM;
405 lgr->is_smcd = ini->is_smcd;
407 lgr->terminating = 0;
410 lgr->vlan_id = ini->vlan_id;
411 mutex_init(&lgr->sndbufs_lock);
412 mutex_init(&lgr->rmbs_lock);
413 rwlock_init(&lgr->conns_lock);
414 for (i = 0; i < SMC_RMBE_SIZES; i++) {
415 INIT_LIST_HEAD(&lgr->sndbufs[i]);
416 INIT_LIST_HEAD(&lgr->rmbs[i]);
418 lgr->next_link_id = 0;
419 smc_lgr_list.num += SMC_LGR_NUM_INCR;
420 memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE);
421 INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
422 INIT_WORK(&lgr->terminate_work, smc_lgr_terminate_work);
423 lgr->conns_all = RB_ROOT;
425 /* SMC-D specific settings */
426 get_device(&ini->ism_dev->dev);
427 lgr->peer_gid = ini->ism_gid;
428 lgr->smcd = ini->ism_dev;
429 lgr_list = &ini->ism_dev->lgr_list;
430 lgr_lock = &lgr->smcd->lgr_lock;
431 lgr->peer_shutdown = 0;
432 atomic_inc(&ini->ism_dev->lgr_cnt);
434 /* SMC-R specific settings */
435 lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
436 memcpy(lgr->peer_systemid, ini->ib_lcl->id_for_peer,
438 memcpy(lgr->pnet_id, ini->ib_dev->pnetid[ini->ib_port - 1],
440 smc_llc_lgr_init(lgr, smc);
442 link_idx = SMC_SINGLE_LINK;
443 lnk = &lgr->lnk[link_idx];
444 rc = smcr_link_init(lgr, lnk, link_idx, ini);
447 lgr_list = &smc_lgr_list.list;
448 lgr_lock = &smc_lgr_list.lock;
449 atomic_inc(&lgr_cnt);
452 spin_lock_bh(lgr_lock);
453 list_add(&lgr->list, lgr_list);
454 spin_unlock_bh(lgr_lock);
460 if (ini->is_smcd && ini->vlan_id)
461 smc_ism_put_vlan(ini->ism_dev, ini->vlan_id);
465 rc = SMC_CLC_DECL_MEM;
467 rc = SMC_CLC_DECL_INTERR;
472 static int smc_write_space(struct smc_connection *conn)
474 int buffer_len = conn->peer_rmbe_size;
475 union smc_host_cursor prod;
476 union smc_host_cursor cons;
479 smc_curs_copy(&prod, &conn->local_tx_ctrl.prod, conn);
480 smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
481 /* determine rx_buf space */
482 space = buffer_len - smc_curs_diff(buffer_len, &cons, &prod);
486 static int smc_switch_cursor(struct smc_sock *smc)
488 struct smc_connection *conn = &smc->conn;
489 union smc_host_cursor cons, fin;
493 smc_curs_copy(&conn->tx_curs_sent, &conn->tx_curs_fin, conn);
494 smc_curs_copy(&fin, &conn->local_tx_ctrl_fin, conn);
495 /* set prod cursor to old state, enforce tx_rdma_writes() */
496 smc_curs_copy(&conn->local_tx_ctrl.prod, &fin, conn);
497 smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
499 if (smc_curs_comp(conn->peer_rmbe_size, &cons, &fin) < 0) {
500 /* cons cursor advanced more than fin, and prod was set
501 * fin above, so now prod is smaller than cons. Fix that.
503 diff = smc_curs_diff(conn->peer_rmbe_size, &fin, &cons);
504 smc_curs_add(conn->sndbuf_desc->len,
505 &conn->tx_curs_sent, diff);
506 smc_curs_add(conn->sndbuf_desc->len,
507 &conn->tx_curs_fin, diff);
509 smp_mb__before_atomic();
510 atomic_add(diff, &conn->sndbuf_space);
511 smp_mb__after_atomic();
513 smc_curs_add(conn->peer_rmbe_size,
514 &conn->local_tx_ctrl.prod, diff);
515 smc_curs_add(conn->peer_rmbe_size,
516 &conn->local_tx_ctrl_fin, diff);
518 /* recalculate, value is used by tx_rdma_writes() */
519 atomic_set(&smc->conn.peer_rmbe_space, smc_write_space(conn));
521 if (smc->sk.sk_state != SMC_INIT &&
522 smc->sk.sk_state != SMC_CLOSED) {
523 rc = smcr_cdc_msg_send_validation(conn);
525 schedule_delayed_work(&conn->tx_work, 0);
526 smc->sk.sk_data_ready(&smc->sk);
532 struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
533 struct smc_link *from_lnk, bool is_dev_err)
535 struct smc_link *to_lnk = NULL;
536 struct smc_connection *conn;
537 struct smc_sock *smc;
538 struct rb_node *node;
541 /* link is inactive, wake up tx waiters */
542 smc_wr_wakeup_tx_wait(from_lnk);
544 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
545 if (lgr->lnk[i].state != SMC_LNK_ACTIVE ||
546 i == from_lnk->link_idx)
548 if (is_dev_err && from_lnk->smcibdev == lgr->lnk[i].smcibdev &&
549 from_lnk->ibport == lgr->lnk[i].ibport) {
552 to_lnk = &lgr->lnk[i];
556 smc_lgr_terminate_sched(lgr);
560 read_lock_bh(&lgr->conns_lock);
561 for (node = rb_first(&lgr->conns_all); node; node = rb_next(node)) {
562 conn = rb_entry(node, struct smc_connection, alert_node);
563 if (conn->lnk != from_lnk)
565 smc = container_of(conn, struct smc_sock, conn);
566 /* conn->lnk not yet set in SMC_INIT state */
567 if (smc->sk.sk_state == SMC_INIT)
569 if (smc->sk.sk_state == SMC_CLOSED ||
570 smc->sk.sk_state == SMC_PEERCLOSEWAIT1 ||
571 smc->sk.sk_state == SMC_PEERCLOSEWAIT2 ||
572 smc->sk.sk_state == SMC_APPFINCLOSEWAIT ||
573 smc->sk.sk_state == SMC_APPCLOSEWAIT1 ||
574 smc->sk.sk_state == SMC_APPCLOSEWAIT2 ||
575 smc->sk.sk_state == SMC_PEERFINCLOSEWAIT ||
576 smc->sk.sk_state == SMC_PEERABORTWAIT ||
577 smc->sk.sk_state == SMC_PROCESSABORT) {
578 spin_lock_bh(&conn->send_lock);
580 spin_unlock_bh(&conn->send_lock);
584 read_unlock_bh(&lgr->conns_lock);
585 /* avoid race with smcr_tx_sndbuf_nonempty() */
586 spin_lock_bh(&conn->send_lock);
588 rc = smc_switch_cursor(smc);
589 spin_unlock_bh(&conn->send_lock);
592 smcr_link_down_cond_sched(to_lnk);
597 read_unlock_bh(&lgr->conns_lock);
601 static void smcr_buf_unuse(struct smc_buf_desc *rmb_desc,
602 struct smc_link_group *lgr)
606 if (rmb_desc->is_conf_rkey && !list_empty(&lgr->list)) {
607 /* unregister rmb with peer */
608 rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
610 /* protect against smc_llc_cli_rkey_exchange() */
611 mutex_lock(&lgr->llc_conf_mutex);
612 smc_llc_do_delete_rkey(lgr, rmb_desc);
613 rmb_desc->is_conf_rkey = false;
614 mutex_unlock(&lgr->llc_conf_mutex);
615 smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
619 if (rmb_desc->is_reg_err) {
620 /* buf registration failed, reuse not possible */
621 mutex_lock(&lgr->rmbs_lock);
622 list_del(&rmb_desc->list);
623 mutex_unlock(&lgr->rmbs_lock);
625 smc_buf_free(lgr, true, rmb_desc);
631 static void smc_buf_unuse(struct smc_connection *conn,
632 struct smc_link_group *lgr)
634 if (conn->sndbuf_desc)
635 conn->sndbuf_desc->used = 0;
636 if (conn->rmb_desc && lgr->is_smcd)
637 conn->rmb_desc->used = 0;
638 else if (conn->rmb_desc)
639 smcr_buf_unuse(conn->rmb_desc, lgr);
642 /* remove a finished connection from its link group */
643 void smc_conn_free(struct smc_connection *conn)
645 struct smc_link_group *lgr = conn->lgr;
650 if (!list_empty(&lgr->list))
651 smc_ism_unset_conn(conn);
652 tasklet_kill(&conn->rx_tsklet);
654 smc_cdc_tx_dismiss_slots(conn);
655 if (current_work() != &conn->abort_work)
656 cancel_work_sync(&conn->abort_work);
658 if (!list_empty(&lgr->list)) {
659 smc_lgr_unregister_conn(conn);
660 smc_buf_unuse(conn, lgr); /* allow buffer reuse */
664 smc_lgr_schedule_free_work(lgr);
667 /* unregister a link from a buf_desc */
668 static void smcr_buf_unmap_link(struct smc_buf_desc *buf_desc, bool is_rmb,
669 struct smc_link *lnk)
672 buf_desc->is_reg_mr[lnk->link_idx] = false;
673 if (!buf_desc->is_map_ib[lnk->link_idx])
676 if (buf_desc->mr_rx[lnk->link_idx]) {
677 smc_ib_put_memory_region(
678 buf_desc->mr_rx[lnk->link_idx]);
679 buf_desc->mr_rx[lnk->link_idx] = NULL;
681 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_FROM_DEVICE);
683 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_TO_DEVICE);
685 sg_free_table(&buf_desc->sgt[lnk->link_idx]);
686 buf_desc->is_map_ib[lnk->link_idx] = false;
689 /* unmap all buffers of lgr for a deleted link */
690 static void smcr_buf_unmap_lgr(struct smc_link *lnk)
692 struct smc_link_group *lgr = lnk->lgr;
693 struct smc_buf_desc *buf_desc, *bf;
696 for (i = 0; i < SMC_RMBE_SIZES; i++) {
697 mutex_lock(&lgr->rmbs_lock);
698 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list)
699 smcr_buf_unmap_link(buf_desc, true, lnk);
700 mutex_unlock(&lgr->rmbs_lock);
701 mutex_lock(&lgr->sndbufs_lock);
702 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i],
704 smcr_buf_unmap_link(buf_desc, false, lnk);
705 mutex_unlock(&lgr->sndbufs_lock);
709 static void smcr_rtoken_clear_link(struct smc_link *lnk)
711 struct smc_link_group *lgr = lnk->lgr;
714 for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
715 lgr->rtokens[i][lnk->link_idx].rkey = 0;
716 lgr->rtokens[i][lnk->link_idx].dma_addr = 0;
720 /* must be called under lgr->llc_conf_mutex lock */
721 void smcr_link_clear(struct smc_link *lnk, bool log)
723 struct smc_ib_device *smcibdev;
725 if (!lnk->lgr || lnk->state == SMC_LNK_UNUSED)
728 smc_llc_link_clear(lnk, log);
729 smcr_buf_unmap_lgr(lnk);
730 smcr_rtoken_clear_link(lnk);
731 smc_ib_modify_qp_reset(lnk);
732 smc_wr_free_link(lnk);
733 smc_ib_destroy_queue_pair(lnk);
734 smc_ib_dealloc_protection_domain(lnk);
735 smc_wr_free_link_mem(lnk);
736 put_device(&lnk->smcibdev->ibdev->dev);
737 smcibdev = lnk->smcibdev;
738 memset(lnk, 0, sizeof(struct smc_link));
739 lnk->state = SMC_LNK_UNUSED;
740 if (!atomic_dec_return(&smcibdev->lnk_cnt))
741 wake_up(&smcibdev->lnks_deleted);
744 static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb,
745 struct smc_buf_desc *buf_desc)
749 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
750 smcr_buf_unmap_link(buf_desc, is_rmb, &lgr->lnk[i]);
753 __free_pages(buf_desc->pages, buf_desc->order);
757 static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb,
758 struct smc_buf_desc *buf_desc)
761 /* restore original buf len */
762 buf_desc->len += sizeof(struct smcd_cdc_msg);
763 smc_ism_unregister_dmb(lgr->smcd, buf_desc);
765 kfree(buf_desc->cpu_addr);
770 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
771 struct smc_buf_desc *buf_desc)
774 smcd_buf_free(lgr, is_rmb, buf_desc);
776 smcr_buf_free(lgr, is_rmb, buf_desc);
779 static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb)
781 struct smc_buf_desc *buf_desc, *bf_desc;
782 struct list_head *buf_list;
785 for (i = 0; i < SMC_RMBE_SIZES; i++) {
787 buf_list = &lgr->rmbs[i];
789 buf_list = &lgr->sndbufs[i];
790 list_for_each_entry_safe(buf_desc, bf_desc, buf_list,
792 list_del(&buf_desc->list);
793 smc_buf_free(lgr, is_rmb, buf_desc);
798 static void smc_lgr_free_bufs(struct smc_link_group *lgr)
800 /* free send buffers */
801 __smc_lgr_free_bufs(lgr, false);
803 __smc_lgr_free_bufs(lgr, true);
806 /* remove a link group */
807 static void smc_lgr_free(struct smc_link_group *lgr)
812 mutex_lock(&lgr->llc_conf_mutex);
813 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
814 if (lgr->lnk[i].state != SMC_LNK_UNUSED)
815 smcr_link_clear(&lgr->lnk[i], false);
817 mutex_unlock(&lgr->llc_conf_mutex);
818 smc_llc_lgr_clear(lgr);
821 smc_lgr_free_bufs(lgr);
823 if (!lgr->terminating) {
824 smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
825 put_device(&lgr->smcd->dev);
827 if (!atomic_dec_return(&lgr->smcd->lgr_cnt))
828 wake_up(&lgr->smcd->lgrs_deleted);
830 if (!atomic_dec_return(&lgr_cnt))
831 wake_up(&lgrs_deleted);
836 static void smcd_unregister_all_dmbs(struct smc_link_group *lgr)
840 for (i = 0; i < SMC_RMBE_SIZES; i++) {
841 struct smc_buf_desc *buf_desc;
843 list_for_each_entry(buf_desc, &lgr->rmbs[i], list) {
844 buf_desc->len += sizeof(struct smcd_cdc_msg);
845 smc_ism_unregister_dmb(lgr->smcd, buf_desc);
850 static void smc_sk_wake_ups(struct smc_sock *smc)
852 smc->sk.sk_write_space(&smc->sk);
853 smc->sk.sk_data_ready(&smc->sk);
854 smc->sk.sk_state_change(&smc->sk);
857 /* kill a connection */
858 static void smc_conn_kill(struct smc_connection *conn, bool soft)
860 struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
862 if (conn->lgr->is_smcd && conn->lgr->peer_shutdown)
863 conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
865 smc_close_abort(conn);
867 smc->sk.sk_err = ECONNABORTED;
868 smc_sk_wake_ups(smc);
869 if (conn->lgr->is_smcd) {
870 smc_ism_unset_conn(conn);
872 tasklet_kill(&conn->rx_tsklet);
874 tasklet_unlock_wait(&conn->rx_tsklet);
876 smc_cdc_tx_dismiss_slots(conn);
878 smc_lgr_unregister_conn(conn);
879 smc_close_active_abort(smc);
882 static void smc_lgr_cleanup(struct smc_link_group *lgr)
885 smc_ism_signal_shutdown(lgr);
886 smcd_unregister_all_dmbs(lgr);
887 smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
888 put_device(&lgr->smcd->dev);
890 u32 rsn = lgr->llc_termination_rsn;
893 rsn = SMC_LLC_DEL_PROG_INIT_TERM;
894 smc_llc_send_link_delete_all(lgr, false, rsn);
895 smcr_lgr_link_deactivate_all(lgr);
899 /* terminate link group
900 * @soft: true if link group shutdown can take its time
901 * false if immediate link group shutdown is required
903 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft)
905 struct smc_connection *conn;
906 struct smc_sock *smc;
907 struct rb_node *node;
909 if (lgr->terminating)
910 return; /* lgr already terminating */
911 /* cancel free_work sync, will terminate when lgr->freeing is set */
912 cancel_delayed_work_sync(&lgr->free_work);
913 lgr->terminating = 1;
915 /* kill remaining link group connections */
916 read_lock_bh(&lgr->conns_lock);
917 node = rb_first(&lgr->conns_all);
919 read_unlock_bh(&lgr->conns_lock);
920 conn = rb_entry(node, struct smc_connection, alert_node);
921 smc = container_of(conn, struct smc_sock, conn);
922 sock_hold(&smc->sk); /* sock_put below */
924 smc_conn_kill(conn, soft);
925 release_sock(&smc->sk);
926 sock_put(&smc->sk); /* sock_hold above */
927 read_lock_bh(&lgr->conns_lock);
928 node = rb_first(&lgr->conns_all);
930 read_unlock_bh(&lgr->conns_lock);
931 smc_lgr_cleanup(lgr);
935 /* unlink link group and schedule termination */
936 void smc_lgr_terminate_sched(struct smc_link_group *lgr)
938 spinlock_t *lgr_lock;
940 smc_lgr_list_head(lgr, &lgr_lock);
941 spin_lock_bh(lgr_lock);
942 if (list_empty(&lgr->list) || lgr->terminating || lgr->freeing) {
943 spin_unlock_bh(lgr_lock);
944 return; /* lgr already terminating */
946 list_del_init(&lgr->list);
948 spin_unlock_bh(lgr_lock);
949 schedule_work(&lgr->terminate_work);
952 /* Called when peer lgr shutdown (regularly or abnormally) is received */
953 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
955 struct smc_link_group *lgr, *l;
956 LIST_HEAD(lgr_free_list);
958 /* run common cleanup function and build free list */
959 spin_lock_bh(&dev->lgr_lock);
960 list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) {
961 if ((!peer_gid || lgr->peer_gid == peer_gid) &&
962 (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
963 if (peer_gid) /* peer triggered termination */
964 lgr->peer_shutdown = 1;
965 list_move(&lgr->list, &lgr_free_list);
969 spin_unlock_bh(&dev->lgr_lock);
971 /* cancel the regular free workers and actually free lgrs */
972 list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
973 list_del_init(&lgr->list);
974 schedule_work(&lgr->terminate_work);
978 /* Called when an SMCD device is removed or the smc module is unloaded */
979 void smc_smcd_terminate_all(struct smcd_dev *smcd)
981 struct smc_link_group *lgr, *lg;
982 LIST_HEAD(lgr_free_list);
984 spin_lock_bh(&smcd->lgr_lock);
985 list_splice_init(&smcd->lgr_list, &lgr_free_list);
986 list_for_each_entry(lgr, &lgr_free_list, list)
988 spin_unlock_bh(&smcd->lgr_lock);
990 list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
991 list_del_init(&lgr->list);
992 __smc_lgr_terminate(lgr, false);
995 if (atomic_read(&smcd->lgr_cnt))
996 wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt));
999 /* Called when an SMCR device is removed or the smc module is unloaded.
1000 * If smcibdev is given, all SMCR link groups using this device are terminated.
1001 * If smcibdev is NULL, all SMCR link groups are terminated.
1003 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
1005 struct smc_link_group *lgr, *lg;
1006 LIST_HEAD(lgr_free_list);
1009 spin_lock_bh(&smc_lgr_list.lock);
1011 list_splice_init(&smc_lgr_list.list, &lgr_free_list);
1012 list_for_each_entry(lgr, &lgr_free_list, list)
1015 list_for_each_entry_safe(lgr, lg, &smc_lgr_list.list, list) {
1016 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1017 if (lgr->lnk[i].smcibdev == smcibdev)
1018 smcr_link_down_cond_sched(&lgr->lnk[i]);
1022 spin_unlock_bh(&smc_lgr_list.lock);
1024 list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1025 list_del_init(&lgr->list);
1026 smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_OP_INIT_TERM);
1027 __smc_lgr_terminate(lgr, false);
1031 if (atomic_read(&smcibdev->lnk_cnt))
1032 wait_event(smcibdev->lnks_deleted,
1033 !atomic_read(&smcibdev->lnk_cnt));
1035 if (atomic_read(&lgr_cnt))
1036 wait_event(lgrs_deleted, !atomic_read(&lgr_cnt));
1040 /* set new lgr type and clear all asymmetric link tagging */
1041 void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type)
1043 char *lgr_type = "";
1046 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1047 if (smc_link_usable(&lgr->lnk[i]))
1048 lgr->lnk[i].link_is_asym = false;
1049 if (lgr->type == new_type)
1051 lgr->type = new_type;
1053 switch (lgr->type) {
1057 case SMC_LGR_SINGLE:
1058 lgr_type = "SINGLE";
1060 case SMC_LGR_SYMMETRIC:
1061 lgr_type = "SYMMETRIC";
1063 case SMC_LGR_ASYMMETRIC_PEER:
1064 lgr_type = "ASYMMETRIC_PEER";
1066 case SMC_LGR_ASYMMETRIC_LOCAL:
1067 lgr_type = "ASYMMETRIC_LOCAL";
1070 pr_warn_ratelimited("smc: SMC-R lg %*phN state changed: "
1071 "%s, pnetid %.16s\n", SMC_LGR_ID_SIZE, &lgr->id,
1072 lgr_type, lgr->pnet_id);
1075 /* set new lgr type and tag a link as asymmetric */
1076 void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
1077 enum smc_lgr_type new_type, int asym_lnk_idx)
1079 smcr_lgr_set_type(lgr, new_type);
1080 lgr->lnk[asym_lnk_idx].link_is_asym = true;
1083 /* abort connection, abort_work scheduled from tasklet context */
1084 static void smc_conn_abort_work(struct work_struct *work)
1086 struct smc_connection *conn = container_of(work,
1087 struct smc_connection,
1089 struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1091 smc_conn_kill(conn, true);
1092 sock_put(&smc->sk); /* sock_hold done by schedulers of abort_work */
1095 /* link is up - establish alternate link if applicable */
1096 static void smcr_link_up(struct smc_link_group *lgr,
1097 struct smc_ib_device *smcibdev, u8 ibport)
1099 struct smc_link *link = NULL;
1101 if (list_empty(&lgr->list) ||
1102 lgr->type == SMC_LGR_SYMMETRIC ||
1103 lgr->type == SMC_LGR_ASYMMETRIC_PEER)
1106 if (lgr->role == SMC_SERV) {
1107 /* trigger local add link processing */
1108 link = smc_llc_usable_link(lgr);
1111 smc_llc_srv_add_link_local(link);
1113 /* invite server to start add link processing */
1114 u8 gid[SMC_GID_SIZE];
1116 if (smc_ib_determine_gid(smcibdev, ibport, lgr->vlan_id, gid,
1119 if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
1120 /* some other llc task is ongoing */
1121 wait_event_interruptible_timeout(lgr->llc_waiter,
1122 (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE),
1125 if (list_empty(&lgr->list) ||
1126 !smc_ib_port_active(smcibdev, ibport))
1127 return; /* lgr or device no longer active */
1128 link = smc_llc_usable_link(lgr);
1131 smc_llc_send_add_link(link, smcibdev->mac[ibport - 1], gid,
1136 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport)
1138 struct smc_ib_up_work *ib_work;
1139 struct smc_link_group *lgr, *n;
1141 list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1142 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1143 SMC_MAX_PNETID_LEN) ||
1144 lgr->type == SMC_LGR_SYMMETRIC ||
1145 lgr->type == SMC_LGR_ASYMMETRIC_PEER)
1147 ib_work = kmalloc(sizeof(*ib_work), GFP_KERNEL);
1150 INIT_WORK(&ib_work->work, smc_link_up_work);
1152 ib_work->smcibdev = smcibdev;
1153 ib_work->ibport = ibport;
1154 schedule_work(&ib_work->work);
1158 /* link is down - switch connections to alternate link,
1159 * must be called under lgr->llc_conf_mutex lock
1161 static void smcr_link_down(struct smc_link *lnk)
1163 struct smc_link_group *lgr = lnk->lgr;
1164 struct smc_link *to_lnk;
1167 if (!lgr || lnk->state == SMC_LNK_UNUSED || list_empty(&lgr->list))
1170 smc_ib_modify_qp_reset(lnk);
1171 to_lnk = smc_switch_conns(lgr, lnk, true);
1172 if (!to_lnk) { /* no backup link available */
1173 smcr_link_clear(lnk, true);
1176 smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
1177 del_link_id = lnk->link_id;
1179 if (lgr->role == SMC_SERV) {
1180 /* trigger local delete link processing */
1181 smc_llc_srv_delete_link_local(to_lnk, del_link_id);
1183 if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
1184 /* another llc task is ongoing */
1185 mutex_unlock(&lgr->llc_conf_mutex);
1186 wait_event_interruptible_timeout(lgr->llc_waiter,
1187 (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE),
1189 mutex_lock(&lgr->llc_conf_mutex);
1191 smc_llc_send_delete_link(to_lnk, del_link_id, SMC_LLC_REQ, true,
1192 SMC_LLC_DEL_LOST_PATH);
1196 /* must be called under lgr->llc_conf_mutex lock */
1197 void smcr_link_down_cond(struct smc_link *lnk)
1199 if (smc_link_downing(&lnk->state))
1200 smcr_link_down(lnk);
1203 /* will get the lgr->llc_conf_mutex lock */
1204 void smcr_link_down_cond_sched(struct smc_link *lnk)
1206 if (smc_link_downing(&lnk->state))
1207 schedule_work(&lnk->link_down_wrk);
1210 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport)
1212 struct smc_link_group *lgr, *n;
1215 list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1216 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1217 SMC_MAX_PNETID_LEN))
1218 continue; /* lgr is not affected */
1219 if (list_empty(&lgr->list))
1221 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1222 struct smc_link *lnk = &lgr->lnk[i];
1224 if (smc_link_usable(lnk) &&
1225 lnk->smcibdev == smcibdev && lnk->ibport == ibport)
1226 smcr_link_down_cond_sched(lnk);
1231 static void smc_link_up_work(struct work_struct *work)
1233 struct smc_ib_up_work *ib_work = container_of(work,
1234 struct smc_ib_up_work,
1236 struct smc_link_group *lgr = ib_work->lgr;
1238 if (list_empty(&lgr->list))
1240 smcr_link_up(lgr, ib_work->smcibdev, ib_work->ibport);
1245 static void smc_link_down_work(struct work_struct *work)
1247 struct smc_link *link = container_of(work, struct smc_link,
1249 struct smc_link_group *lgr = link->lgr;
1251 if (list_empty(&lgr->list))
1253 wake_up_interruptible_all(&lgr->llc_waiter);
1254 mutex_lock(&lgr->llc_conf_mutex);
1255 smcr_link_down(link);
1256 mutex_unlock(&lgr->llc_conf_mutex);
1259 /* Determine vlan of internal TCP socket.
1260 * @vlan_id: address to store the determined vlan id into
1262 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
1264 struct dst_entry *dst = sk_dst_get(clcsock->sk);
1265 struct net_device *ndev;
1266 int i, nest_lvl, rc = 0;
1279 if (is_vlan_dev(ndev)) {
1280 ini->vlan_id = vlan_dev_vlan_id(ndev);
1285 nest_lvl = ndev->lower_level;
1286 for (i = 0; i < nest_lvl; i++) {
1287 struct list_head *lower = &ndev->adj_list.lower;
1289 if (list_empty(lower))
1291 lower = lower->next;
1292 ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower);
1293 if (is_vlan_dev(ndev)) {
1294 ini->vlan_id = vlan_dev_vlan_id(ndev);
1306 static bool smcr_lgr_match(struct smc_link_group *lgr,
1307 struct smc_clc_msg_local *lcl,
1308 enum smc_lgr_role role, u32 clcqpn)
1312 if (memcmp(lgr->peer_systemid, lcl->id_for_peer, SMC_SYSTEMID_LEN) ||
1316 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1317 if (lgr->lnk[i].state != SMC_LNK_ACTIVE)
1319 if ((lgr->role == SMC_SERV || lgr->lnk[i].peer_qpn == clcqpn) &&
1320 !memcmp(lgr->lnk[i].peer_gid, &lcl->gid, SMC_GID_SIZE) &&
1321 !memcmp(lgr->lnk[i].peer_mac, lcl->mac, sizeof(lcl->mac)))
1327 static bool smcd_lgr_match(struct smc_link_group *lgr,
1328 struct smcd_dev *smcismdev, u64 peer_gid)
1330 return lgr->peer_gid == peer_gid && lgr->smcd == smcismdev;
1333 /* create a new SMC connection (and a new link group if necessary) */
1334 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
1336 struct smc_connection *conn = &smc->conn;
1337 struct list_head *lgr_list;
1338 struct smc_link_group *lgr;
1339 enum smc_lgr_role role;
1340 spinlock_t *lgr_lock;
1343 lgr_list = ini->is_smcd ? &ini->ism_dev->lgr_list : &smc_lgr_list.list;
1344 lgr_lock = ini->is_smcd ? &ini->ism_dev->lgr_lock : &smc_lgr_list.lock;
1345 ini->cln_first_contact = SMC_FIRST_CONTACT;
1346 role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
1347 if (role == SMC_CLNT && ini->srv_first_contact)
1348 /* create new link group as well */
1351 /* determine if an existing link group can be reused */
1352 spin_lock_bh(lgr_lock);
1353 list_for_each_entry(lgr, lgr_list, list) {
1354 write_lock_bh(&lgr->conns_lock);
1356 smcd_lgr_match(lgr, ini->ism_dev, ini->ism_gid) :
1357 smcr_lgr_match(lgr, ini->ib_lcl, role, ini->ib_clcqpn)) &&
1359 lgr->vlan_id == ini->vlan_id &&
1360 (role == SMC_CLNT ||
1361 lgr->conns_num < SMC_RMBS_PER_LGR_MAX)) {
1362 /* link group found */
1363 ini->cln_first_contact = SMC_REUSE_CONTACT;
1365 rc = smc_lgr_register_conn(conn, false);
1366 write_unlock_bh(&lgr->conns_lock);
1367 if (!rc && delayed_work_pending(&lgr->free_work))
1368 cancel_delayed_work(&lgr->free_work);
1371 write_unlock_bh(&lgr->conns_lock);
1373 spin_unlock_bh(lgr_lock);
1377 if (role == SMC_CLNT && !ini->srv_first_contact &&
1378 ini->cln_first_contact == SMC_FIRST_CONTACT) {
1379 /* Server reuses a link group, but Client wants to start
1381 * send out_of_sync decline, reason synchr. error
1383 return SMC_CLC_DECL_SYNCERR;
1387 if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
1388 rc = smc_lgr_create(smc, ini);
1392 write_lock_bh(&lgr->conns_lock);
1393 rc = smc_lgr_register_conn(conn, true);
1394 write_unlock_bh(&lgr->conns_lock);
1398 conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
1399 conn->local_tx_ctrl.len = SMC_WR_TX_SIZE;
1400 conn->urg_state = SMC_URG_READ;
1401 INIT_WORK(&smc->conn.abort_work, smc_conn_abort_work);
1403 conn->rx_off = sizeof(struct smcd_cdc_msg);
1404 smcd_cdc_rx_init(conn); /* init tasklet for this conn */
1406 #ifndef KERNEL_HAS_ATOMIC64
1407 spin_lock_init(&conn->acurs_lock);
1414 /* convert the RMB size into the compressed notation - minimum 16K.
1415 * In contrast to plain ilog2, this rounds towards the next power of 2,
1416 * so the socket application gets at least its desired sndbuf / rcvbuf size.
1418 static u8 smc_compress_bufsize(int size)
1422 if (size <= SMC_BUF_MIN_SIZE)
1425 size = (size - 1) >> 14;
1426 compressed = ilog2(size) + 1;
1427 if (compressed >= SMC_RMBE_SIZES)
1428 compressed = SMC_RMBE_SIZES - 1;
1432 /* convert the RMB size from compressed notation into integer */
1433 int smc_uncompress_bufsize(u8 compressed)
1437 size = 0x00000001 << (((int)compressed) + 14);
1441 /* try to reuse a sndbuf or rmb description slot for a certain
1442 * buffer size; if not available, return NULL
1444 static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize,
1446 struct list_head *buf_list)
1448 struct smc_buf_desc *buf_slot;
1451 list_for_each_entry(buf_slot, buf_list, list) {
1452 if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
1461 /* one of the conditions for announcing a receiver's current window size is
1462 * that it "results in a minimum increase in the window size of 10% of the
1463 * receive buffer space" [RFC7609]
1465 static inline int smc_rmb_wnd_update_limit(int rmbe_size)
1467 return min_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
1470 /* map an rmb buf to a link */
1471 static int smcr_buf_map_link(struct smc_buf_desc *buf_desc, bool is_rmb,
1472 struct smc_link *lnk)
1476 if (buf_desc->is_map_ib[lnk->link_idx])
1479 rc = sg_alloc_table(&buf_desc->sgt[lnk->link_idx], 1, GFP_KERNEL);
1482 sg_set_buf(buf_desc->sgt[lnk->link_idx].sgl,
1483 buf_desc->cpu_addr, buf_desc->len);
1485 /* map sg table to DMA address */
1486 rc = smc_ib_buf_map_sg(lnk, buf_desc,
1487 is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
1488 /* SMC protocol depends on mapping to one DMA address only */
1494 /* create a new memory region for the RMB */
1496 rc = smc_ib_get_memory_region(lnk->roce_pd,
1497 IB_ACCESS_REMOTE_WRITE |
1498 IB_ACCESS_LOCAL_WRITE,
1499 buf_desc, lnk->link_idx);
1502 smc_ib_sync_sg_for_device(lnk, buf_desc, DMA_FROM_DEVICE);
1504 buf_desc->is_map_ib[lnk->link_idx] = true;
1508 smc_ib_buf_unmap_sg(lnk, buf_desc,
1509 is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
1511 sg_free_table(&buf_desc->sgt[lnk->link_idx]);
1515 /* register a new rmb on IB device,
1516 * must be called under lgr->llc_conf_mutex lock
1518 int smcr_link_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc)
1520 if (list_empty(&link->lgr->list))
1522 if (!rmb_desc->is_reg_mr[link->link_idx]) {
1523 /* register memory region for new rmb */
1524 if (smc_wr_reg_send(link, rmb_desc->mr_rx[link->link_idx])) {
1525 rmb_desc->is_reg_err = true;
1528 rmb_desc->is_reg_mr[link->link_idx] = true;
1533 static int _smcr_buf_map_lgr(struct smc_link *lnk, struct mutex *lock,
1534 struct list_head *lst, bool is_rmb)
1536 struct smc_buf_desc *buf_desc, *bf;
1540 list_for_each_entry_safe(buf_desc, bf, lst, list) {
1541 if (!buf_desc->used)
1543 rc = smcr_buf_map_link(buf_desc, is_rmb, lnk);
1552 /* map all used buffers of lgr for a new link */
1553 int smcr_buf_map_lgr(struct smc_link *lnk)
1555 struct smc_link_group *lgr = lnk->lgr;
1558 for (i = 0; i < SMC_RMBE_SIZES; i++) {
1559 rc = _smcr_buf_map_lgr(lnk, &lgr->rmbs_lock,
1560 &lgr->rmbs[i], true);
1563 rc = _smcr_buf_map_lgr(lnk, &lgr->sndbufs_lock,
1564 &lgr->sndbufs[i], false);
1571 /* register all used buffers of lgr for a new link,
1572 * must be called under lgr->llc_conf_mutex lock
1574 int smcr_buf_reg_lgr(struct smc_link *lnk)
1576 struct smc_link_group *lgr = lnk->lgr;
1577 struct smc_buf_desc *buf_desc, *bf;
1580 mutex_lock(&lgr->rmbs_lock);
1581 for (i = 0; i < SMC_RMBE_SIZES; i++) {
1582 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list) {
1583 if (!buf_desc->used)
1585 rc = smcr_link_reg_rmb(lnk, buf_desc);
1591 mutex_unlock(&lgr->rmbs_lock);
1595 static struct smc_buf_desc *smcr_new_buf_create(struct smc_link_group *lgr,
1596 bool is_rmb, int bufsize)
1598 struct smc_buf_desc *buf_desc;
1600 /* try to alloc a new buffer */
1601 buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
1603 return ERR_PTR(-ENOMEM);
1605 buf_desc->order = get_order(bufsize);
1606 buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN |
1607 __GFP_NOMEMALLOC | __GFP_COMP |
1608 __GFP_NORETRY | __GFP_ZERO,
1610 if (!buf_desc->pages) {
1612 return ERR_PTR(-EAGAIN);
1614 buf_desc->cpu_addr = (void *)page_address(buf_desc->pages);
1615 buf_desc->len = bufsize;
1619 /* map buf_desc on all usable links,
1620 * unused buffers stay mapped as long as the link is up
1622 static int smcr_buf_map_usable_links(struct smc_link_group *lgr,
1623 struct smc_buf_desc *buf_desc, bool is_rmb)
1627 /* protect against parallel link reconfiguration */
1628 mutex_lock(&lgr->llc_conf_mutex);
1629 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1630 struct smc_link *lnk = &lgr->lnk[i];
1632 if (!smc_link_usable(lnk))
1634 if (smcr_buf_map_link(buf_desc, is_rmb, lnk)) {
1640 mutex_unlock(&lgr->llc_conf_mutex);
1644 #define SMCD_DMBE_SIZES 7 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */
1646 static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr,
1647 bool is_dmb, int bufsize)
1649 struct smc_buf_desc *buf_desc;
1652 if (smc_compress_bufsize(bufsize) > SMCD_DMBE_SIZES)
1653 return ERR_PTR(-EAGAIN);
1655 /* try to alloc a new DMB */
1656 buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
1658 return ERR_PTR(-ENOMEM);
1660 rc = smc_ism_register_dmb(lgr, bufsize, buf_desc);
1663 return ERR_PTR(-EAGAIN);
1665 buf_desc->pages = virt_to_page(buf_desc->cpu_addr);
1666 /* CDC header stored in buf. So, pretend it was smaller */
1667 buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg);
1669 buf_desc->cpu_addr = kzalloc(bufsize, GFP_KERNEL |
1670 __GFP_NOWARN | __GFP_NORETRY |
1672 if (!buf_desc->cpu_addr) {
1674 return ERR_PTR(-EAGAIN);
1676 buf_desc->len = bufsize;
1681 static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb)
1683 struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM);
1684 struct smc_connection *conn = &smc->conn;
1685 struct smc_link_group *lgr = conn->lgr;
1686 struct list_head *buf_list;
1687 int bufsize, bufsize_short;
1688 struct mutex *lock; /* lock buffer list */
1692 /* use socket recv buffer size (w/o overhead) as start value */
1693 sk_buf_size = smc->sk.sk_rcvbuf / 2;
1695 /* use socket send buffer size (w/o overhead) as start value */
1696 sk_buf_size = smc->sk.sk_sndbuf / 2;
1698 for (bufsize_short = smc_compress_bufsize(sk_buf_size);
1699 bufsize_short >= 0; bufsize_short--) {
1702 lock = &lgr->rmbs_lock;
1703 buf_list = &lgr->rmbs[bufsize_short];
1705 lock = &lgr->sndbufs_lock;
1706 buf_list = &lgr->sndbufs[bufsize_short];
1708 bufsize = smc_uncompress_bufsize(bufsize_short);
1709 if ((1 << get_order(bufsize)) > SG_MAX_SINGLE_ALLOC)
1712 /* check for reusable slot in the link group */
1713 buf_desc = smc_buf_get_slot(bufsize_short, lock, buf_list);
1715 memset(buf_desc->cpu_addr, 0, bufsize);
1716 break; /* found reusable slot */
1720 buf_desc = smcd_new_buf_create(lgr, is_rmb, bufsize);
1722 buf_desc = smcr_new_buf_create(lgr, is_rmb, bufsize);
1724 if (PTR_ERR(buf_desc) == -ENOMEM)
1726 if (IS_ERR(buf_desc))
1731 list_add(&buf_desc->list, buf_list);
1736 if (IS_ERR(buf_desc))
1740 if (smcr_buf_map_usable_links(lgr, buf_desc, is_rmb)) {
1741 smcr_buf_unuse(buf_desc, lgr);
1747 conn->rmb_desc = buf_desc;
1748 conn->rmbe_size_short = bufsize_short;
1749 smc->sk.sk_rcvbuf = bufsize * 2;
1750 atomic_set(&conn->bytes_to_rcv, 0);
1751 conn->rmbe_update_limit =
1752 smc_rmb_wnd_update_limit(buf_desc->len);
1754 smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */
1756 conn->sndbuf_desc = buf_desc;
1757 smc->sk.sk_sndbuf = bufsize * 2;
1758 atomic_set(&conn->sndbuf_space, bufsize);
1763 void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn)
1765 if (!conn->lgr || conn->lgr->is_smcd || !smc_link_usable(conn->lnk))
1767 smc_ib_sync_sg_for_cpu(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
1770 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
1772 if (!conn->lgr || conn->lgr->is_smcd || !smc_link_usable(conn->lnk))
1774 smc_ib_sync_sg_for_device(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
1777 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
1781 if (!conn->lgr || conn->lgr->is_smcd)
1783 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1784 if (!smc_link_usable(&conn->lgr->lnk[i]))
1786 smc_ib_sync_sg_for_cpu(&conn->lgr->lnk[i], conn->rmb_desc,
1791 void smc_rmb_sync_sg_for_device(struct smc_connection *conn)
1795 if (!conn->lgr || conn->lgr->is_smcd)
1797 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1798 if (!smc_link_usable(&conn->lgr->lnk[i]))
1800 smc_ib_sync_sg_for_device(&conn->lgr->lnk[i], conn->rmb_desc,
1805 /* create the send and receive buffer for an SMC socket;
1806 * receive buffers are called RMBs;
1807 * (even though the SMC protocol allows more than one RMB-element per RMB,
1808 * the Linux implementation uses just one RMB-element per RMB, i.e. uses an
1809 * extra RMB for every connection in a link group
1811 int smc_buf_create(struct smc_sock *smc, bool is_smcd)
1815 /* create send buffer */
1816 rc = __smc_buf_create(smc, is_smcd, false);
1820 rc = __smc_buf_create(smc, is_smcd, true);
1822 smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc);
1826 static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
1830 for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) {
1831 if (!test_and_set_bit(i, lgr->rtokens_used_mask))
1837 static int smc_rtoken_find_by_link(struct smc_link_group *lgr, int lnk_idx,
1842 for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1843 if (test_bit(i, lgr->rtokens_used_mask) &&
1844 lgr->rtokens[i][lnk_idx].rkey == rkey)
1850 /* set rtoken for a new link to an existing rmb */
1851 void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
1852 __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey)
1856 rtok_idx = smc_rtoken_find_by_link(lgr, link_idx, ntohl(nw_rkey_known));
1857 if (rtok_idx == -ENOENT)
1859 lgr->rtokens[rtok_idx][link_idx_new].rkey = ntohl(nw_rkey);
1860 lgr->rtokens[rtok_idx][link_idx_new].dma_addr = be64_to_cpu(nw_vaddr);
1863 /* set rtoken for a new link whose link_id is given */
1864 void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
1865 __be64 nw_vaddr, __be32 nw_rkey)
1867 u64 dma_addr = be64_to_cpu(nw_vaddr);
1868 u32 rkey = ntohl(nw_rkey);
1872 for (link_idx = 0; link_idx < SMC_LINKS_PER_LGR_MAX; link_idx++) {
1873 if (lgr->lnk[link_idx].link_id == link_id) {
1880 lgr->rtokens[rtok_idx][link_idx].rkey = rkey;
1881 lgr->rtokens[rtok_idx][link_idx].dma_addr = dma_addr;
1884 /* add a new rtoken from peer */
1885 int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey)
1887 struct smc_link_group *lgr = smc_get_lgr(lnk);
1888 u64 dma_addr = be64_to_cpu(nw_vaddr);
1889 u32 rkey = ntohl(nw_rkey);
1892 for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1893 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
1894 lgr->rtokens[i][lnk->link_idx].dma_addr == dma_addr &&
1895 test_bit(i, lgr->rtokens_used_mask)) {
1896 /* already in list */
1900 i = smc_rmb_reserve_rtoken_idx(lgr);
1903 lgr->rtokens[i][lnk->link_idx].rkey = rkey;
1904 lgr->rtokens[i][lnk->link_idx].dma_addr = dma_addr;
1908 /* delete an rtoken from all links */
1909 int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey)
1911 struct smc_link_group *lgr = smc_get_lgr(lnk);
1912 u32 rkey = ntohl(nw_rkey);
1915 for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1916 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
1917 test_bit(i, lgr->rtokens_used_mask)) {
1918 for (j = 0; j < SMC_LINKS_PER_LGR_MAX; j++) {
1919 lgr->rtokens[i][j].rkey = 0;
1920 lgr->rtokens[i][j].dma_addr = 0;
1922 clear_bit(i, lgr->rtokens_used_mask);
1929 /* save rkey and dma_addr received from peer during clc handshake */
1930 int smc_rmb_rtoken_handling(struct smc_connection *conn,
1931 struct smc_link *lnk,
1932 struct smc_clc_msg_accept_confirm *clc)
1934 conn->rtoken_idx = smc_rtoken_add(lnk, clc->rmb_dma_addr,
1936 if (conn->rtoken_idx < 0)
1937 return conn->rtoken_idx;
1941 static void smc_core_going_away(void)
1943 struct smc_ib_device *smcibdev;
1944 struct smcd_dev *smcd;
1946 spin_lock(&smc_ib_devices.lock);
1947 list_for_each_entry(smcibdev, &smc_ib_devices.list, list) {
1950 for (i = 0; i < SMC_MAX_PORTS; i++)
1951 set_bit(i, smcibdev->ports_going_away);
1953 spin_unlock(&smc_ib_devices.lock);
1955 spin_lock(&smcd_dev_list.lock);
1956 list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1957 smcd->going_away = 1;
1959 spin_unlock(&smcd_dev_list.lock);
1962 /* Clean up all SMC link groups */
1963 static void smc_lgrs_shutdown(void)
1965 struct smcd_dev *smcd;
1967 smc_core_going_away();
1969 smc_smcr_terminate_all(NULL);
1971 spin_lock(&smcd_dev_list.lock);
1972 list_for_each_entry(smcd, &smcd_dev_list.list, list)
1973 smc_smcd_terminate_all(smcd);
1974 spin_unlock(&smcd_dev_list.lock);
1977 static int smc_core_reboot_event(struct notifier_block *this,
1978 unsigned long event, void *ptr)
1980 smc_lgrs_shutdown();
1981 smc_ib_unregister_client();
1985 static struct notifier_block smc_reboot_notifier = {
1986 .notifier_call = smc_core_reboot_event,
1989 int __init smc_core_init(void)
1991 return register_reboot_notifier(&smc_reboot_notifier);
1994 /* Called (from smc_exit) when module is removed */
1995 void smc_core_exit(void)
1997 unregister_reboot_notifier(&smc_reboot_notifier);
1998 smc_lgrs_shutdown();