1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *  Shared Memory Communications over RDMA (SMC-R) and RoCE
   4 *
   5 *  Basic Transport Functions exploiting Infiniband API
   6 *
   7 *  Copyright IBM Corp. 2016
   8 *
   9 *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
  10 */
  11
  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>
  18#include <linux/mutex.h>
 
 
  19#include <net/tcp.h>
  20#include <net/sock.h>
  21#include <rdma/ib_verbs.h>
  22#include <rdma/ib_cache.h>
  23
  24#include "smc.h"
  25#include "smc_clc.h"
  26#include "smc_core.h"
  27#include "smc_ib.h"
  28#include "smc_wr.h"
  29#include "smc_llc.h"
  30#include "smc_cdc.h"
  31#include "smc_close.h"
  32#include "smc_ism.h"
 
 
  33
  34#define SMC_LGR_NUM_INCR		256
  35#define SMC_LGR_FREE_DELAY_SERV		(600 * HZ)
  36#define SMC_LGR_FREE_DELAY_CLNT		(SMC_LGR_FREE_DELAY_SERV + 10 * HZ)
  37#define SMC_LGR_FREE_DELAY_FAST		(8 * HZ)
  38
  39static struct smc_lgr_list smc_lgr_list = {	/* established link groups */
  40	.lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
  41	.list = LIST_HEAD_INIT(smc_lgr_list.list),
  42	.num = 0,
  43};
  44
  45static atomic_t lgr_cnt = ATOMIC_INIT(0); /* number of existing link groups */
  46static DECLARE_WAIT_QUEUE_HEAD(lgrs_deleted);
  47
  48static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
  49			 struct smc_buf_desc *buf_desc);
  50static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft);
  51
  52static void smc_link_down_work(struct work_struct *work);
  53
  54/* return head of link group list and its lock for a given link group */
  55static inline struct list_head *smc_lgr_list_head(struct smc_link_group *lgr,
  56						  spinlock_t **lgr_lock)
  57{
  58	if (lgr->is_smcd) {
  59		*lgr_lock = &lgr->smcd->lgr_lock;
  60		return &lgr->smcd->lgr_list;
  61	}
  62
  63	*lgr_lock = &smc_lgr_list.lock;
  64	return &smc_lgr_list.list;
  65}
  66
 
 
 
 
 
 
 
 
 
 
  67static void smc_lgr_schedule_free_work(struct smc_link_group *lgr)
  68{
  69	/* client link group creation always follows the server link group
  70	 * creation. For client use a somewhat higher removal delay time,
  71	 * otherwise there is a risk of out-of-sync link groups.
  72	 */
  73	if (!lgr->freeing && !lgr->freefast) {
  74		mod_delayed_work(system_wq, &lgr->free_work,
  75				 (!lgr->is_smcd && lgr->role == SMC_CLNT) ?
  76						SMC_LGR_FREE_DELAY_CLNT :
  77						SMC_LGR_FREE_DELAY_SERV);
  78	}
  79}
  80
  81void smc_lgr_schedule_free_work_fast(struct smc_link_group *lgr)
  82{
  83	if (!lgr->freeing && !lgr->freefast) {
  84		lgr->freefast = 1;
  85		mod_delayed_work(system_wq, &lgr->free_work,
  86				 SMC_LGR_FREE_DELAY_FAST);
  87	}
  88}
  89
  90/* Register connection's alert token in our lookup structure.
  91 * To use rbtrees we have to implement our own insert core.
  92 * Requires @conns_lock
  93 * @smc		connection to register
  94 * Returns 0 on success, != otherwise.
  95 */
  96static void smc_lgr_add_alert_token(struct smc_connection *conn)
  97{
  98	struct rb_node **link, *parent = NULL;
  99	u32 token = conn->alert_token_local;
 100
 101	link = &conn->lgr->conns_all.rb_node;
 102	while (*link) {
 103		struct smc_connection *cur = rb_entry(*link,
 104					struct smc_connection, alert_node);
 105
 106		parent = *link;
 107		if (cur->alert_token_local > token)
 108			link = &parent->rb_left;
 109		else
 110			link = &parent->rb_right;
 111	}
 112	/* Put the new node there */
 113	rb_link_node(&conn->alert_node, parent, link);
 114	rb_insert_color(&conn->alert_node, &conn->lgr->conns_all);
 115}
 116
 117/* assign an SMC-R link to the connection */
 118static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first)
 119{
 120	enum smc_link_state expected = first ? SMC_LNK_ACTIVATING :
 121				       SMC_LNK_ACTIVE;
 122	int i, j;
 123
 124	/* do link balancing */
 125	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 126		struct smc_link *lnk = &conn->lgr->lnk[i];
 127
 128		if (lnk->state != expected || lnk->link_is_asym)
 129			continue;
 130		if (conn->lgr->role == SMC_CLNT) {
 131			conn->lnk = lnk; /* temporary, SMC server assigns link*/
 132			break;
 133		}
 134		if (conn->lgr->conns_num % 2) {
 135			for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) {
 136				struct smc_link *lnk2;
 137
 138				lnk2 = &conn->lgr->lnk[j];
 139				if (lnk2->state == expected &&
 140				    !lnk2->link_is_asym) {
 141					conn->lnk = lnk2;
 142					break;
 143				}
 144			}
 145		}
 146		if (!conn->lnk)
 147			conn->lnk = lnk;
 148		break;
 149	}
 150	if (!conn->lnk)
 151		return SMC_CLC_DECL_NOACTLINK;
 
 152	return 0;
 153}
 154
 155/* Register connection in link group by assigning an alert token
 156 * registered in a search tree.
 157 * Requires @conns_lock
 158 * Note that '0' is a reserved value and not assigned.
 159 */
 160static int smc_lgr_register_conn(struct smc_connection *conn, bool first)
 161{
 162	struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 163	static atomic_t nexttoken = ATOMIC_INIT(0);
 164	int rc;
 165
 166	if (!conn->lgr->is_smcd) {
 167		rc = smcr_lgr_conn_assign_link(conn, first);
 168		if (rc)
 169			return rc;
 170	}
 171	/* find a new alert_token_local value not yet used by some connection
 172	 * in this link group
 173	 */
 174	sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */
 175	while (!conn->alert_token_local) {
 176		conn->alert_token_local = atomic_inc_return(&nexttoken);
 177		if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr))
 178			conn->alert_token_local = 0;
 179	}
 180	smc_lgr_add_alert_token(conn);
 181	conn->lgr->conns_num++;
 182	return 0;
 183}
 184
 185/* Unregister connection and reset the alert token of the given connection<
 186 */
 187static void __smc_lgr_unregister_conn(struct smc_connection *conn)
 188{
 189	struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 190	struct smc_link_group *lgr = conn->lgr;
 191
 192	rb_erase(&conn->alert_node, &lgr->conns_all);
 
 
 193	lgr->conns_num--;
 194	conn->alert_token_local = 0;
 195	sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
 196}
 197
 198/* Unregister connection from lgr
 199 */
 200static void smc_lgr_unregister_conn(struct smc_connection *conn)
 201{
 202	struct smc_link_group *lgr = conn->lgr;
 203
 204	if (!lgr)
 205		return;
 206	write_lock_bh(&lgr->conns_lock);
 207	if (conn->alert_token_local) {
 208		__smc_lgr_unregister_conn(conn);
 209	}
 210	write_unlock_bh(&lgr->conns_lock);
 211	conn->lgr = NULL;
 212}
 213
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 214void smc_lgr_cleanup_early(struct smc_connection *conn)
 215{
 216	struct smc_link_group *lgr = conn->lgr;
 217	struct list_head *lgr_list;
 218	spinlock_t *lgr_lock;
 219
 220	if (!lgr)
 221		return;
 222
 223	smc_conn_free(conn);
 224	lgr_list = smc_lgr_list_head(lgr, &lgr_lock);
 225	spin_lock_bh(lgr_lock);
 226	/* do not use this link group for new connections */
 227	if (!list_empty(lgr_list))
 228		list_del_init(lgr_list);
 229	spin_unlock_bh(lgr_lock);
 230	smc_lgr_schedule_free_work_fast(lgr);
 231}
 232
 233static void smcr_lgr_link_deactivate_all(struct smc_link_group *lgr)
 234{
 235	int i;
 236
 237	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 238		struct smc_link *lnk = &lgr->lnk[i];
 239
 240		if (smc_link_usable(lnk))
 241			lnk->state = SMC_LNK_INACTIVE;
 242	}
 243	wake_up_all(&lgr->llc_msg_waiter);
 244	wake_up_all(&lgr->llc_flow_waiter);
 245}
 246
 247static void smc_lgr_free(struct smc_link_group *lgr);
 248
 249static void smc_lgr_free_work(struct work_struct *work)
 250{
 251	struct smc_link_group *lgr = container_of(to_delayed_work(work),
 252						  struct smc_link_group,
 253						  free_work);
 254	spinlock_t *lgr_lock;
 255	bool conns;
 256
 257	smc_lgr_list_head(lgr, &lgr_lock);
 258	spin_lock_bh(lgr_lock);
 259	if (lgr->freeing) {
 260		spin_unlock_bh(lgr_lock);
 261		return;
 262	}
 263	read_lock_bh(&lgr->conns_lock);
 264	conns = RB_EMPTY_ROOT(&lgr->conns_all);
 265	read_unlock_bh(&lgr->conns_lock);
 266	if (!conns) { /* number of lgr connections is no longer zero */
 267		spin_unlock_bh(lgr_lock);
 268		return;
 269	}
 270	list_del_init(&lgr->list); /* remove from smc_lgr_list */
 271	lgr->freeing = 1; /* this instance does the freeing, no new schedule */
 272	spin_unlock_bh(lgr_lock);
 273	cancel_delayed_work(&lgr->free_work);
 274
 275	if (!lgr->is_smcd && !lgr->terminating)
 276		smc_llc_send_link_delete_all(lgr, true,
 277					     SMC_LLC_DEL_PROG_INIT_TERM);
 278	if (lgr->is_smcd && !lgr->terminating)
 279		smc_ism_signal_shutdown(lgr);
 280	if (!lgr->is_smcd)
 281		smcr_lgr_link_deactivate_all(lgr);
 282	smc_lgr_free(lgr);
 283}
 284
 285static void smc_lgr_terminate_work(struct work_struct *work)
 286{
 287	struct smc_link_group *lgr = container_of(work, struct smc_link_group,
 288						  terminate_work);
 289
 290	__smc_lgr_terminate(lgr, true);
 291}
 292
 293/* return next unique link id for the lgr */
 294static u8 smcr_next_link_id(struct smc_link_group *lgr)
 295{
 296	u8 link_id;
 297	int i;
 298
 299	while (1) {
 300		link_id = ++lgr->next_link_id;
 301		if (!link_id)	/* skip zero as link_id */
 302			link_id = ++lgr->next_link_id;
 303		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 304			if (smc_link_usable(&lgr->lnk[i]) &&
 305			    lgr->lnk[i].link_id == link_id)
 306				continue;
 307		}
 308		break;
 309	}
 310	return link_id;
 311}
 312
 
 
 
 
 
 
 
 
 
 313int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
 314		   u8 link_idx, struct smc_init_info *ini)
 315{
 316	u8 rndvec[3];
 317	int rc;
 318
 319	get_device(&ini->ib_dev->ibdev->dev);
 320	atomic_inc(&ini->ib_dev->lnk_cnt);
 321	lnk->link_id = smcr_next_link_id(lgr);
 322	lnk->lgr = lgr;
 323	lnk->link_idx = link_idx;
 324	lnk->smcibdev = ini->ib_dev;
 325	lnk->ibport = ini->ib_port;
 
 
 326	lnk->path_mtu = ini->ib_dev->pattr[ini->ib_port - 1].active_mtu;
 
 327	smc_llc_link_set_uid(lnk);
 328	INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
 329	if (!ini->ib_dev->initialized) {
 330		rc = (int)smc_ib_setup_per_ibdev(ini->ib_dev);
 331		if (rc)
 332			goto out;
 333	}
 334	get_random_bytes(rndvec, sizeof(rndvec));
 335	lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) +
 336		(rndvec[2] << 16);
 337	rc = smc_ib_determine_gid(lnk->smcibdev, lnk->ibport,
 338				  ini->vlan_id, lnk->gid, &lnk->sgid_index);
 339	if (rc)
 340		goto out;
 341	rc = smc_llc_link_init(lnk);
 342	if (rc)
 343		goto out;
 344	rc = smc_wr_alloc_link_mem(lnk);
 345	if (rc)
 346		goto clear_llc_lnk;
 347	rc = smc_ib_create_protection_domain(lnk);
 348	if (rc)
 349		goto free_link_mem;
 350	rc = smc_ib_create_queue_pair(lnk);
 351	if (rc)
 352		goto dealloc_pd;
 353	rc = smc_wr_create_link(lnk);
 354	if (rc)
 355		goto destroy_qp;
 356	lnk->state = SMC_LNK_ACTIVATING;
 357	return 0;
 358
 359destroy_qp:
 360	smc_ib_destroy_queue_pair(lnk);
 361dealloc_pd:
 362	smc_ib_dealloc_protection_domain(lnk);
 363free_link_mem:
 364	smc_wr_free_link_mem(lnk);
 365clear_llc_lnk:
 366	smc_llc_link_clear(lnk, false);
 367out:
 
 368	put_device(&ini->ib_dev->ibdev->dev);
 369	memset(lnk, 0, sizeof(struct smc_link));
 370	lnk->state = SMC_LNK_UNUSED;
 371	if (!atomic_dec_return(&ini->ib_dev->lnk_cnt))
 372		wake_up(&ini->ib_dev->lnks_deleted);
 373	return rc;
 374}
 375
 376/* create a new SMC link group */
 377static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
 378{
 379	struct smc_link_group *lgr;
 380	struct list_head *lgr_list;
 381	struct smc_link *lnk;
 382	spinlock_t *lgr_lock;
 383	u8 link_idx;
 384	int rc = 0;
 385	int i;
 386
 387	if (ini->is_smcd && ini->vlan_id) {
 388		if (smc_ism_get_vlan(ini->ism_dev, ini->vlan_id)) {
 
 389			rc = SMC_CLC_DECL_ISMVLANERR;
 390			goto out;
 391		}
 392	}
 393
 394	lgr = kzalloc(sizeof(*lgr), GFP_KERNEL);
 395	if (!lgr) {
 396		rc = SMC_CLC_DECL_MEM;
 397		goto ism_put_vlan;
 398	}
 
 
 
 
 
 
 399	lgr->is_smcd = ini->is_smcd;
 400	lgr->sync_err = 0;
 401	lgr->terminating = 0;
 402	lgr->freefast = 0;
 403	lgr->freeing = 0;
 404	lgr->vlan_id = ini->vlan_id;
 405	mutex_init(&lgr->sndbufs_lock);
 406	mutex_init(&lgr->rmbs_lock);
 407	rwlock_init(&lgr->conns_lock);
 408	for (i = 0; i < SMC_RMBE_SIZES; i++) {
 409		INIT_LIST_HEAD(&lgr->sndbufs[i]);
 410		INIT_LIST_HEAD(&lgr->rmbs[i]);
 411	}
 412	lgr->next_link_id = 0;
 413	smc_lgr_list.num += SMC_LGR_NUM_INCR;
 414	memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE);
 415	INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
 416	INIT_WORK(&lgr->terminate_work, smc_lgr_terminate_work);
 417	lgr->conns_all = RB_ROOT;
 418	if (ini->is_smcd) {
 419		/* SMC-D specific settings */
 420		get_device(&ini->ism_dev->dev);
 421		lgr->peer_gid = ini->ism_gid;
 422		lgr->smcd = ini->ism_dev;
 423		lgr_list = &ini->ism_dev->lgr_list;
 424		lgr_lock = &lgr->smcd->lgr_lock;
 
 425		lgr->peer_shutdown = 0;
 426		atomic_inc(&ini->ism_dev->lgr_cnt);
 427	} else {
 428		/* SMC-R specific settings */
 429		lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
 430		memcpy(lgr->peer_systemid, ini->ib_lcl->id_for_peer,
 431		       SMC_SYSTEMID_LEN);
 432		memcpy(lgr->pnet_id, ini->ib_dev->pnetid[ini->ib_port - 1],
 433		       SMC_MAX_PNETID_LEN);
 434		smc_llc_lgr_init(lgr, smc);
 435
 436		link_idx = SMC_SINGLE_LINK;
 437		lnk = &lgr->lnk[link_idx];
 438		rc = smcr_link_init(lgr, lnk, link_idx, ini);
 439		if (rc)
 440			goto free_lgr;
 441		lgr_list = &smc_lgr_list.list;
 442		lgr_lock = &smc_lgr_list.lock;
 443		atomic_inc(&lgr_cnt);
 444	}
 445	smc->conn.lgr = lgr;
 446	spin_lock_bh(lgr_lock);
 447	list_add_tail(&lgr->list, lgr_list);
 448	spin_unlock_bh(lgr_lock);
 449	return 0;
 450
 
 
 451free_lgr:
 452	kfree(lgr);
 453ism_put_vlan:
 454	if (ini->is_smcd && ini->vlan_id)
 455		smc_ism_put_vlan(ini->ism_dev, ini->vlan_id);
 456out:
 457	if (rc < 0) {
 458		if (rc == -ENOMEM)
 459			rc = SMC_CLC_DECL_MEM;
 460		else
 461			rc = SMC_CLC_DECL_INTERR;
 462	}
 463	return rc;
 464}
 465
 466static int smc_write_space(struct smc_connection *conn)
 467{
 468	int buffer_len = conn->peer_rmbe_size;
 469	union smc_host_cursor prod;
 470	union smc_host_cursor cons;
 471	int space;
 472
 473	smc_curs_copy(&prod, &conn->local_tx_ctrl.prod, conn);
 474	smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
 475	/* determine rx_buf space */
 476	space = buffer_len - smc_curs_diff(buffer_len, &cons, &prod);
 477	return space;
 478}
 479
 480static int smc_switch_cursor(struct smc_sock *smc, struct smc_cdc_tx_pend *pend,
 481			     struct smc_wr_buf *wr_buf)
 482{
 483	struct smc_connection *conn = &smc->conn;
 484	union smc_host_cursor cons, fin;
 485	int rc = 0;
 486	int diff;
 487
 488	smc_curs_copy(&conn->tx_curs_sent, &conn->tx_curs_fin, conn);
 489	smc_curs_copy(&fin, &conn->local_tx_ctrl_fin, conn);
 490	/* set prod cursor to old state, enforce tx_rdma_writes() */
 491	smc_curs_copy(&conn->local_tx_ctrl.prod, &fin, conn);
 492	smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
 493
 494	if (smc_curs_comp(conn->peer_rmbe_size, &cons, &fin) < 0) {
 495		/* cons cursor advanced more than fin, and prod was set
 496		 * fin above, so now prod is smaller than cons. Fix that.
 497		 */
 498		diff = smc_curs_diff(conn->peer_rmbe_size, &fin, &cons);
 499		smc_curs_add(conn->sndbuf_desc->len,
 500			     &conn->tx_curs_sent, diff);
 501		smc_curs_add(conn->sndbuf_desc->len,
 502			     &conn->tx_curs_fin, diff);
 503
 504		smp_mb__before_atomic();
 505		atomic_add(diff, &conn->sndbuf_space);
 506		smp_mb__after_atomic();
 507
 508		smc_curs_add(conn->peer_rmbe_size,
 509			     &conn->local_tx_ctrl.prod, diff);
 510		smc_curs_add(conn->peer_rmbe_size,
 511			     &conn->local_tx_ctrl_fin, diff);
 512	}
 513	/* recalculate, value is used by tx_rdma_writes() */
 514	atomic_set(&smc->conn.peer_rmbe_space, smc_write_space(conn));
 515
 516	if (smc->sk.sk_state != SMC_INIT &&
 517	    smc->sk.sk_state != SMC_CLOSED) {
 518		rc = smcr_cdc_msg_send_validation(conn, pend, wr_buf);
 519		if (!rc) {
 520			schedule_delayed_work(&conn->tx_work, 0);
 521			smc->sk.sk_data_ready(&smc->sk);
 522		}
 523	} else {
 524		smc_wr_tx_put_slot(conn->lnk,
 525				   (struct smc_wr_tx_pend_priv *)pend);
 526	}
 527	return rc;
 528}
 529
 
 
 
 
 
 
 
 
 530struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
 531				  struct smc_link *from_lnk, bool is_dev_err)
 532{
 533	struct smc_link *to_lnk = NULL;
 534	struct smc_cdc_tx_pend *pend;
 535	struct smc_connection *conn;
 536	struct smc_wr_buf *wr_buf;
 537	struct smc_sock *smc;
 538	struct rb_node *node;
 539	int i, rc = 0;
 540
 541	/* link is inactive, wake up tx waiters */
 542	smc_wr_wakeup_tx_wait(from_lnk);
 543
 544	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 545		if (!smc_link_active(&lgr->lnk[i]) || i == from_lnk->link_idx)
 546			continue;
 547		if (is_dev_err && from_lnk->smcibdev == lgr->lnk[i].smcibdev &&
 548		    from_lnk->ibport == lgr->lnk[i].ibport) {
 549			continue;
 550		}
 551		to_lnk = &lgr->lnk[i];
 552		break;
 553	}
 554	if (!to_lnk) {
 555		smc_lgr_terminate_sched(lgr);
 556		return NULL;
 557	}
 558again:
 559	read_lock_bh(&lgr->conns_lock);
 560	for (node = rb_first(&lgr->conns_all); node; node = rb_next(node)) {
 561		conn = rb_entry(node, struct smc_connection, alert_node);
 562		if (conn->lnk != from_lnk)
 563			continue;
 564		smc = container_of(conn, struct smc_sock, conn);
 565		/* conn->lnk not yet set in SMC_INIT state */
 566		if (smc->sk.sk_state == SMC_INIT)
 567			continue;
 568		if (smc->sk.sk_state == SMC_CLOSED ||
 569		    smc->sk.sk_state == SMC_PEERCLOSEWAIT1 ||
 570		    smc->sk.sk_state == SMC_PEERCLOSEWAIT2 ||
 571		    smc->sk.sk_state == SMC_APPFINCLOSEWAIT ||
 572		    smc->sk.sk_state == SMC_APPCLOSEWAIT1 ||
 573		    smc->sk.sk_state == SMC_APPCLOSEWAIT2 ||
 574		    smc->sk.sk_state == SMC_PEERFINCLOSEWAIT ||
 575		    smc->sk.sk_state == SMC_PEERABORTWAIT ||
 576		    smc->sk.sk_state == SMC_PROCESSABORT) {
 577			spin_lock_bh(&conn->send_lock);
 578			conn->lnk = to_lnk;
 579			spin_unlock_bh(&conn->send_lock);
 580			continue;
 581		}
 582		sock_hold(&smc->sk);
 583		read_unlock_bh(&lgr->conns_lock);
 584		/* pre-fetch buffer outside of send_lock, might sleep */
 585		rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend);
 586		if (rc) {
 587			smcr_link_down_cond_sched(to_lnk);
 588			return NULL;
 589		}
 590		/* avoid race with smcr_tx_sndbuf_nonempty() */
 591		spin_lock_bh(&conn->send_lock);
 592		conn->lnk = to_lnk;
 593		rc = smc_switch_cursor(smc, pend, wr_buf);
 594		spin_unlock_bh(&conn->send_lock);
 595		sock_put(&smc->sk);
 596		if (rc) {
 597			smcr_link_down_cond_sched(to_lnk);
 598			return NULL;
 599		}
 600		goto again;
 601	}
 602	read_unlock_bh(&lgr->conns_lock);
 
 603	return to_lnk;
 
 
 
 
 
 604}
 605
 606static void smcr_buf_unuse(struct smc_buf_desc *rmb_desc,
 607			   struct smc_link_group *lgr)
 608{
 609	int rc;
 610
 611	if (rmb_desc->is_conf_rkey && !list_empty(&lgr->list)) {
 612		/* unregister rmb with peer */
 613		rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
 614		if (!rc) {
 615			/* protect against smc_llc_cli_rkey_exchange() */
 616			mutex_lock(&lgr->llc_conf_mutex);
 617			smc_llc_do_delete_rkey(lgr, rmb_desc);
 618			rmb_desc->is_conf_rkey = false;
 619			mutex_unlock(&lgr->llc_conf_mutex);
 620			smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
 621		}
 622	}
 623
 624	if (rmb_desc->is_reg_err) {
 625		/* buf registration failed, reuse not possible */
 626		mutex_lock(&lgr->rmbs_lock);
 627		list_del(&rmb_desc->list);
 628		mutex_unlock(&lgr->rmbs_lock);
 629
 630		smc_buf_free(lgr, true, rmb_desc);
 631	} else {
 632		rmb_desc->used = 0;
 633	}
 634}
 635
 636static void smc_buf_unuse(struct smc_connection *conn,
 637			  struct smc_link_group *lgr)
 638{
 639	if (conn->sndbuf_desc)
 640		conn->sndbuf_desc->used = 0;
 641	if (conn->rmb_desc && lgr->is_smcd)
 642		conn->rmb_desc->used = 0;
 643	else if (conn->rmb_desc)
 644		smcr_buf_unuse(conn->rmb_desc, lgr);
 645}
 646
 647/* remove a finished connection from its link group */
 648void smc_conn_free(struct smc_connection *conn)
 649{
 650	struct smc_link_group *lgr = conn->lgr;
 651
 652	if (!lgr)
 653		return;
 654	if (lgr->is_smcd) {
 655		if (!list_empty(&lgr->list))
 656			smc_ism_unset_conn(conn);
 657		tasklet_kill(&conn->rx_tsklet);
 658	} else {
 659		smc_cdc_tx_dismiss_slots(conn);
 660		if (current_work() != &conn->abort_work)
 661			cancel_work_sync(&conn->abort_work);
 662	}
 663	if (!list_empty(&lgr->list)) {
 664		smc_lgr_unregister_conn(conn);
 665		smc_buf_unuse(conn, lgr); /* allow buffer reuse */
 666	}
 667
 668	if (!lgr->conns_num)
 669		smc_lgr_schedule_free_work(lgr);
 670}
 671
 672/* unregister a link from a buf_desc */
 673static void smcr_buf_unmap_link(struct smc_buf_desc *buf_desc, bool is_rmb,
 674				struct smc_link *lnk)
 675{
 676	if (is_rmb)
 677		buf_desc->is_reg_mr[lnk->link_idx] = false;
 678	if (!buf_desc->is_map_ib[lnk->link_idx])
 679		return;
 680	if (is_rmb) {
 681		if (buf_desc->mr_rx[lnk->link_idx]) {
 682			smc_ib_put_memory_region(
 683					buf_desc->mr_rx[lnk->link_idx]);
 684			buf_desc->mr_rx[lnk->link_idx] = NULL;
 685		}
 686		smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_FROM_DEVICE);
 687	} else {
 688		smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_TO_DEVICE);
 689	}
 690	sg_free_table(&buf_desc->sgt[lnk->link_idx]);
 691	buf_desc->is_map_ib[lnk->link_idx] = false;
 692}
 693
 694/* unmap all buffers of lgr for a deleted link */
 695static void smcr_buf_unmap_lgr(struct smc_link *lnk)
 696{
 697	struct smc_link_group *lgr = lnk->lgr;
 698	struct smc_buf_desc *buf_desc, *bf;
 699	int i;
 700
 701	for (i = 0; i < SMC_RMBE_SIZES; i++) {
 702		mutex_lock(&lgr->rmbs_lock);
 703		list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list)
 704			smcr_buf_unmap_link(buf_desc, true, lnk);
 705		mutex_unlock(&lgr->rmbs_lock);
 706		mutex_lock(&lgr->sndbufs_lock);
 707		list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i],
 708					 list)
 709			smcr_buf_unmap_link(buf_desc, false, lnk);
 710		mutex_unlock(&lgr->sndbufs_lock);
 711	}
 712}
 713
 714static void smcr_rtoken_clear_link(struct smc_link *lnk)
 715{
 716	struct smc_link_group *lgr = lnk->lgr;
 717	int i;
 718
 719	for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
 720		lgr->rtokens[i][lnk->link_idx].rkey = 0;
 721		lgr->rtokens[i][lnk->link_idx].dma_addr = 0;
 722	}
 723}
 724
 725/* must be called under lgr->llc_conf_mutex lock */
 726void smcr_link_clear(struct smc_link *lnk, bool log)
 727{
 728	struct smc_ib_device *smcibdev;
 729
 730	if (!lnk->lgr || lnk->state == SMC_LNK_UNUSED)
 731		return;
 732	lnk->peer_qpn = 0;
 733	smc_llc_link_clear(lnk, log);
 734	smcr_buf_unmap_lgr(lnk);
 735	smcr_rtoken_clear_link(lnk);
 736	smc_ib_modify_qp_reset(lnk);
 737	smc_wr_free_link(lnk);
 738	smc_ib_destroy_queue_pair(lnk);
 739	smc_ib_dealloc_protection_domain(lnk);
 740	smc_wr_free_link_mem(lnk);
 
 741	put_device(&lnk->smcibdev->ibdev->dev);
 742	smcibdev = lnk->smcibdev;
 743	memset(lnk, 0, sizeof(struct smc_link));
 744	lnk->state = SMC_LNK_UNUSED;
 745	if (!atomic_dec_return(&smcibdev->lnk_cnt))
 746		wake_up(&smcibdev->lnks_deleted);
 747}
 748
 749static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb,
 750			  struct smc_buf_desc *buf_desc)
 751{
 752	int i;
 753
 754	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
 755		smcr_buf_unmap_link(buf_desc, is_rmb, &lgr->lnk[i]);
 756
 757	if (buf_desc->pages)
 758		__free_pages(buf_desc->pages, buf_desc->order);
 759	kfree(buf_desc);
 760}
 761
 762static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb,
 763			  struct smc_buf_desc *buf_desc)
 764{
 765	if (is_dmb) {
 766		/* restore original buf len */
 767		buf_desc->len += sizeof(struct smcd_cdc_msg);
 768		smc_ism_unregister_dmb(lgr->smcd, buf_desc);
 769	} else {
 770		kfree(buf_desc->cpu_addr);
 771	}
 772	kfree(buf_desc);
 773}
 774
 775static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
 776			 struct smc_buf_desc *buf_desc)
 777{
 778	if (lgr->is_smcd)
 779		smcd_buf_free(lgr, is_rmb, buf_desc);
 780	else
 781		smcr_buf_free(lgr, is_rmb, buf_desc);
 782}
 783
 784static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb)
 785{
 786	struct smc_buf_desc *buf_desc, *bf_desc;
 787	struct list_head *buf_list;
 788	int i;
 789
 790	for (i = 0; i < SMC_RMBE_SIZES; i++) {
 791		if (is_rmb)
 792			buf_list = &lgr->rmbs[i];
 793		else
 794			buf_list = &lgr->sndbufs[i];
 795		list_for_each_entry_safe(buf_desc, bf_desc, buf_list,
 796					 list) {
 797			list_del(&buf_desc->list);
 798			smc_buf_free(lgr, is_rmb, buf_desc);
 799		}
 800	}
 801}
 802
 803static void smc_lgr_free_bufs(struct smc_link_group *lgr)
 804{
 805	/* free send buffers */
 806	__smc_lgr_free_bufs(lgr, false);
 807	/* free rmbs */
 808	__smc_lgr_free_bufs(lgr, true);
 809}
 810
 811/* remove a link group */
 812static void smc_lgr_free(struct smc_link_group *lgr)
 813{
 814	int i;
 815
 816	if (!lgr->is_smcd) {
 817		mutex_lock(&lgr->llc_conf_mutex);
 818		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 819			if (lgr->lnk[i].state != SMC_LNK_UNUSED)
 820				smcr_link_clear(&lgr->lnk[i], false);
 821		}
 822		mutex_unlock(&lgr->llc_conf_mutex);
 823		smc_llc_lgr_clear(lgr);
 824	}
 825
 826	smc_lgr_free_bufs(lgr);
 
 827	if (lgr->is_smcd) {
 828		if (!lgr->terminating) {
 829			smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
 830			put_device(&lgr->smcd->dev);
 831		}
 832		if (!atomic_dec_return(&lgr->smcd->lgr_cnt))
 833			wake_up(&lgr->smcd->lgrs_deleted);
 834	} else {
 835		if (!atomic_dec_return(&lgr_cnt))
 836			wake_up(&lgrs_deleted);
 837	}
 838	kfree(lgr);
 839}
 840
 841static void smcd_unregister_all_dmbs(struct smc_link_group *lgr)
 842{
 843	int i;
 844
 845	for (i = 0; i < SMC_RMBE_SIZES; i++) {
 846		struct smc_buf_desc *buf_desc;
 847
 848		list_for_each_entry(buf_desc, &lgr->rmbs[i], list) {
 849			buf_desc->len += sizeof(struct smcd_cdc_msg);
 850			smc_ism_unregister_dmb(lgr->smcd, buf_desc);
 851		}
 852	}
 853}
 854
 855static void smc_sk_wake_ups(struct smc_sock *smc)
 856{
 857	smc->sk.sk_write_space(&smc->sk);
 858	smc->sk.sk_data_ready(&smc->sk);
 859	smc->sk.sk_state_change(&smc->sk);
 860}
 861
 862/* kill a connection */
 863static void smc_conn_kill(struct smc_connection *conn, bool soft)
 864{
 865	struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 866
 867	if (conn->lgr->is_smcd && conn->lgr->peer_shutdown)
 868		conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
 869	else
 870		smc_close_abort(conn);
 871	conn->killed = 1;
 872	smc->sk.sk_err = ECONNABORTED;
 873	smc_sk_wake_ups(smc);
 874	if (conn->lgr->is_smcd) {
 875		smc_ism_unset_conn(conn);
 876		if (soft)
 877			tasklet_kill(&conn->rx_tsklet);
 878		else
 879			tasklet_unlock_wait(&conn->rx_tsklet);
 880	} else {
 881		smc_cdc_tx_dismiss_slots(conn);
 882	}
 883	smc_lgr_unregister_conn(conn);
 884	smc_close_active_abort(smc);
 885}
 886
 887static void smc_lgr_cleanup(struct smc_link_group *lgr)
 888{
 889	if (lgr->is_smcd) {
 890		smc_ism_signal_shutdown(lgr);
 891		smcd_unregister_all_dmbs(lgr);
 892		smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
 893		put_device(&lgr->smcd->dev);
 894	} else {
 895		u32 rsn = lgr->llc_termination_rsn;
 896
 897		if (!rsn)
 898			rsn = SMC_LLC_DEL_PROG_INIT_TERM;
 899		smc_llc_send_link_delete_all(lgr, false, rsn);
 900		smcr_lgr_link_deactivate_all(lgr);
 901	}
 902}
 903
 904/* terminate link group
 905 * @soft: true if link group shutdown can take its time
 906 *	  false if immediate link group shutdown is required
 907 */
 908static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft)
 909{
 910	struct smc_connection *conn;
 911	struct smc_sock *smc;
 912	struct rb_node *node;
 913
 914	if (lgr->terminating)
 915		return;	/* lgr already terminating */
 916	/* cancel free_work sync, will terminate when lgr->freeing is set */
 917	cancel_delayed_work_sync(&lgr->free_work);
 918	lgr->terminating = 1;
 919
 920	/* kill remaining link group connections */
 921	read_lock_bh(&lgr->conns_lock);
 922	node = rb_first(&lgr->conns_all);
 923	while (node) {
 924		read_unlock_bh(&lgr->conns_lock);
 925		conn = rb_entry(node, struct smc_connection, alert_node);
 926		smc = container_of(conn, struct smc_sock, conn);
 927		sock_hold(&smc->sk); /* sock_put below */
 928		lock_sock(&smc->sk);
 929		smc_conn_kill(conn, soft);
 930		release_sock(&smc->sk);
 931		sock_put(&smc->sk); /* sock_hold above */
 932		read_lock_bh(&lgr->conns_lock);
 933		node = rb_first(&lgr->conns_all);
 934	}
 935	read_unlock_bh(&lgr->conns_lock);
 936	smc_lgr_cleanup(lgr);
 937	smc_lgr_free(lgr);
 938}
 939
 940/* unlink link group and schedule termination */
 941void smc_lgr_terminate_sched(struct smc_link_group *lgr)
 942{
 943	spinlock_t *lgr_lock;
 944
 945	smc_lgr_list_head(lgr, &lgr_lock);
 946	spin_lock_bh(lgr_lock);
 947	if (list_empty(&lgr->list) || lgr->terminating || lgr->freeing) {
 948		spin_unlock_bh(lgr_lock);
 949		return;	/* lgr already terminating */
 950	}
 951	list_del_init(&lgr->list);
 952	lgr->freeing = 1;
 953	spin_unlock_bh(lgr_lock);
 954	schedule_work(&lgr->terminate_work);
 955}
 956
 957/* Called when peer lgr shutdown (regularly or abnormally) is received */
 958void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
 959{
 960	struct smc_link_group *lgr, *l;
 961	LIST_HEAD(lgr_free_list);
 962
 963	/* run common cleanup function and build free list */
 964	spin_lock_bh(&dev->lgr_lock);
 965	list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) {
 966		if ((!peer_gid || lgr->peer_gid == peer_gid) &&
 967		    (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
 968			if (peer_gid) /* peer triggered termination */
 969				lgr->peer_shutdown = 1;
 970			list_move(&lgr->list, &lgr_free_list);
 971			lgr->freeing = 1;
 972		}
 973	}
 974	spin_unlock_bh(&dev->lgr_lock);
 975
 976	/* cancel the regular free workers and actually free lgrs */
 977	list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
 978		list_del_init(&lgr->list);
 979		schedule_work(&lgr->terminate_work);
 980	}
 981}
 982
 983/* Called when an SMCD device is removed or the smc module is unloaded */
 984void smc_smcd_terminate_all(struct smcd_dev *smcd)
 985{
 986	struct smc_link_group *lgr, *lg;
 987	LIST_HEAD(lgr_free_list);
 988
 989	spin_lock_bh(&smcd->lgr_lock);
 990	list_splice_init(&smcd->lgr_list, &lgr_free_list);
 991	list_for_each_entry(lgr, &lgr_free_list, list)
 992		lgr->freeing = 1;
 993	spin_unlock_bh(&smcd->lgr_lock);
 994
 995	list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
 996		list_del_init(&lgr->list);
 997		__smc_lgr_terminate(lgr, false);
 998	}
 999
1000	if (atomic_read(&smcd->lgr_cnt))
1001		wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt));
1002}
1003
1004/* Called when an SMCR device is removed or the smc module is unloaded.
1005 * If smcibdev is given, all SMCR link groups using this device are terminated.
1006 * If smcibdev is NULL, all SMCR link groups are terminated.
1007 */
1008void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
1009{
1010	struct smc_link_group *lgr, *lg;
1011	LIST_HEAD(lgr_free_list);
1012	int i;
1013
1014	spin_lock_bh(&smc_lgr_list.lock);
1015	if (!smcibdev) {
1016		list_splice_init(&smc_lgr_list.list, &lgr_free_list);
1017		list_for_each_entry(lgr, &lgr_free_list, list)
1018			lgr->freeing = 1;
1019	} else {
1020		list_for_each_entry_safe(lgr, lg, &smc_lgr_list.list, list) {
1021			for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1022				if (lgr->lnk[i].smcibdev == smcibdev)
1023					smcr_link_down_cond_sched(&lgr->lnk[i]);
1024			}
1025		}
1026	}
1027	spin_unlock_bh(&smc_lgr_list.lock);
1028
1029	list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1030		list_del_init(&lgr->list);
1031		smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_OP_INIT_TERM);
1032		__smc_lgr_terminate(lgr, false);
1033	}
1034
1035	if (smcibdev) {
1036		if (atomic_read(&smcibdev->lnk_cnt))
1037			wait_event(smcibdev->lnks_deleted,
1038				   !atomic_read(&smcibdev->lnk_cnt));
1039	} else {
1040		if (atomic_read(&lgr_cnt))
1041			wait_event(lgrs_deleted, !atomic_read(&lgr_cnt));
1042	}
1043}
1044
1045/* set new lgr type and clear all asymmetric link tagging */
1046void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type)
1047{
1048	char *lgr_type = "";
1049	int i;
1050
1051	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1052		if (smc_link_usable(&lgr->lnk[i]))
1053			lgr->lnk[i].link_is_asym = false;
1054	if (lgr->type == new_type)
1055		return;
1056	lgr->type = new_type;
1057
1058	switch (lgr->type) {
1059	case SMC_LGR_NONE:
1060		lgr_type = "NONE";
1061		break;
1062	case SMC_LGR_SINGLE:
1063		lgr_type = "SINGLE";
1064		break;
1065	case SMC_LGR_SYMMETRIC:
1066		lgr_type = "SYMMETRIC";
1067		break;
1068	case SMC_LGR_ASYMMETRIC_PEER:
1069		lgr_type = "ASYMMETRIC_PEER";
1070		break;
1071	case SMC_LGR_ASYMMETRIC_LOCAL:
1072		lgr_type = "ASYMMETRIC_LOCAL";
1073		break;
1074	}
1075	pr_warn_ratelimited("smc: SMC-R lg %*phN state changed: "
1076			    "%s, pnetid %.16s\n", SMC_LGR_ID_SIZE, &lgr->id,
1077			    lgr_type, lgr->pnet_id);
1078}
1079
1080/* set new lgr type and tag a link as asymmetric */
1081void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
1082			    enum smc_lgr_type new_type, int asym_lnk_idx)
1083{
1084	smcr_lgr_set_type(lgr, new_type);
1085	lgr->lnk[asym_lnk_idx].link_is_asym = true;
1086}
1087
1088/* abort connection, abort_work scheduled from tasklet context */
1089static void smc_conn_abort_work(struct work_struct *work)
1090{
1091	struct smc_connection *conn = container_of(work,
1092						   struct smc_connection,
1093						   abort_work);
1094	struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1095
 
1096	smc_conn_kill(conn, true);
 
1097	sock_put(&smc->sk); /* sock_hold done by schedulers of abort_work */
1098}
1099
1100void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport)
1101{
1102	struct smc_link_group *lgr, *n;
1103
1104	list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1105		struct smc_link *link;
1106
1107		if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1108			    SMC_MAX_PNETID_LEN) ||
1109		    lgr->type == SMC_LGR_SYMMETRIC ||
1110		    lgr->type == SMC_LGR_ASYMMETRIC_PEER)
1111			continue;
1112
1113		/* trigger local add link processing */
1114		link = smc_llc_usable_link(lgr);
1115		if (link)
1116			smc_llc_add_link_local(link);
1117	}
1118}
1119
1120/* link is down - switch connections to alternate link,
1121 * must be called under lgr->llc_conf_mutex lock
1122 */
1123static void smcr_link_down(struct smc_link *lnk)
1124{
1125	struct smc_link_group *lgr = lnk->lgr;
1126	struct smc_link *to_lnk;
1127	int del_link_id;
1128
1129	if (!lgr || lnk->state == SMC_LNK_UNUSED || list_empty(&lgr->list))
1130		return;
1131
1132	smc_ib_modify_qp_reset(lnk);
1133	to_lnk = smc_switch_conns(lgr, lnk, true);
1134	if (!to_lnk) { /* no backup link available */
1135		smcr_link_clear(lnk, true);
1136		return;
1137	}
1138	smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
1139	del_link_id = lnk->link_id;
1140
1141	if (lgr->role == SMC_SERV) {
1142		/* trigger local delete link processing */
1143		smc_llc_srv_delete_link_local(to_lnk, del_link_id);
1144	} else {
1145		if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
1146			/* another llc task is ongoing */
1147			mutex_unlock(&lgr->llc_conf_mutex);
1148			wait_event_timeout(lgr->llc_flow_waiter,
1149				(list_empty(&lgr->list) ||
1150				 lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE),
1151				SMC_LLC_WAIT_TIME);
1152			mutex_lock(&lgr->llc_conf_mutex);
1153		}
1154		if (!list_empty(&lgr->list)) {
1155			smc_llc_send_delete_link(to_lnk, del_link_id,
1156						 SMC_LLC_REQ, true,
1157						 SMC_LLC_DEL_LOST_PATH);
1158			smcr_link_clear(lnk, true);
1159		}
1160		wake_up(&lgr->llc_flow_waiter);	/* wake up next waiter */
1161	}
1162}
1163
1164/* must be called under lgr->llc_conf_mutex lock */
1165void smcr_link_down_cond(struct smc_link *lnk)
1166{
1167	if (smc_link_downing(&lnk->state))
1168		smcr_link_down(lnk);
1169}
1170
1171/* will get the lgr->llc_conf_mutex lock */
1172void smcr_link_down_cond_sched(struct smc_link *lnk)
1173{
1174	if (smc_link_downing(&lnk->state))
1175		schedule_work(&lnk->link_down_wrk);
1176}
1177
1178void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport)
1179{
1180	struct smc_link_group *lgr, *n;
1181	int i;
1182
1183	list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1184		if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1185			    SMC_MAX_PNETID_LEN))
1186			continue; /* lgr is not affected */
1187		if (list_empty(&lgr->list))
1188			continue;
1189		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1190			struct smc_link *lnk = &lgr->lnk[i];
1191
1192			if (smc_link_usable(lnk) &&
1193			    lnk->smcibdev == smcibdev && lnk->ibport == ibport)
1194				smcr_link_down_cond_sched(lnk);
1195		}
1196	}
1197}
1198
1199static void smc_link_down_work(struct work_struct *work)
1200{
1201	struct smc_link *link = container_of(work, struct smc_link,
1202					     link_down_wrk);
1203	struct smc_link_group *lgr = link->lgr;
1204
1205	if (list_empty(&lgr->list))
1206		return;
1207	wake_up_all(&lgr->llc_msg_waiter);
1208	mutex_lock(&lgr->llc_conf_mutex);
1209	smcr_link_down(link);
1210	mutex_unlock(&lgr->llc_conf_mutex);
1211}
1212
1213/* Determine vlan of internal TCP socket.
1214 * @vlan_id: address to store the determined vlan id into
1215 */
1216int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
1217{
1218	struct dst_entry *dst = sk_dst_get(clcsock->sk);
1219	struct net_device *ndev;
1220	int i, nest_lvl, rc = 0;
1221
1222	ini->vlan_id = 0;
1223	if (!dst) {
1224		rc = -ENOTCONN;
1225		goto out;
1226	}
1227	if (!dst->dev) {
1228		rc = -ENODEV;
1229		goto out_rel;
1230	}
1231
1232	ndev = dst->dev;
1233	if (is_vlan_dev(ndev)) {
1234		ini->vlan_id = vlan_dev_vlan_id(ndev);
1235		goto out_rel;
1236	}
1237
1238	rtnl_lock();
1239	nest_lvl = ndev->lower_level;
1240	for (i = 0; i < nest_lvl; i++) {
1241		struct list_head *lower = &ndev->adj_list.lower;
1242
1243		if (list_empty(lower))
1244			break;
1245		lower = lower->next;
1246		ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower);
1247		if (is_vlan_dev(ndev)) {
1248			ini->vlan_id = vlan_dev_vlan_id(ndev);
1249			break;
1250		}
1251	}
1252	rtnl_unlock();
1253
1254out_rel:
1255	dst_release(dst);
1256out:
1257	return rc;
1258}
1259
1260static bool smcr_lgr_match(struct smc_link_group *lgr,
1261			   struct smc_clc_msg_local *lcl,
1262			   enum smc_lgr_role role, u32 clcqpn)
1263{
1264	int i;
1265
1266	if (memcmp(lgr->peer_systemid, lcl->id_for_peer, SMC_SYSTEMID_LEN) ||
1267	    lgr->role != role)
1268		return false;
1269
1270	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1271		if (!smc_link_active(&lgr->lnk[i]))
1272			continue;
1273		if ((lgr->role == SMC_SERV || lgr->lnk[i].peer_qpn == clcqpn) &&
1274		    !memcmp(lgr->lnk[i].peer_gid, &lcl->gid, SMC_GID_SIZE) &&
1275		    !memcmp(lgr->lnk[i].peer_mac, lcl->mac, sizeof(lcl->mac)))
1276			return true;
1277	}
1278	return false;
1279}
1280
1281static bool smcd_lgr_match(struct smc_link_group *lgr,
1282			   struct smcd_dev *smcismdev, u64 peer_gid)
1283{
1284	return lgr->peer_gid == peer_gid && lgr->smcd == smcismdev;
1285}
1286
1287/* create a new SMC connection (and a new link group if necessary) */
1288int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
1289{
1290	struct smc_connection *conn = &smc->conn;
1291	struct list_head *lgr_list;
1292	struct smc_link_group *lgr;
1293	enum smc_lgr_role role;
1294	spinlock_t *lgr_lock;
1295	int rc = 0;
1296
1297	lgr_list = ini->is_smcd ? &ini->ism_dev->lgr_list : &smc_lgr_list.list;
1298	lgr_lock = ini->is_smcd ? &ini->ism_dev->lgr_lock : &smc_lgr_list.lock;
1299	ini->cln_first_contact = SMC_FIRST_CONTACT;
 
 
1300	role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
1301	if (role == SMC_CLNT && ini->srv_first_contact)
1302		/* create new link group as well */
1303		goto create;
1304
1305	/* determine if an existing link group can be reused */
1306	spin_lock_bh(lgr_lock);
1307	list_for_each_entry(lgr, lgr_list, list) {
1308		write_lock_bh(&lgr->conns_lock);
1309		if ((ini->is_smcd ?
1310		     smcd_lgr_match(lgr, ini->ism_dev, ini->ism_gid) :
 
1311		     smcr_lgr_match(lgr, ini->ib_lcl, role, ini->ib_clcqpn)) &&
1312		    !lgr->sync_err &&
1313		    lgr->vlan_id == ini->vlan_id &&
 
1314		    (role == SMC_CLNT || ini->is_smcd ||
1315		     lgr->conns_num < SMC_RMBS_PER_LGR_MAX)) {
1316			/* link group found */
1317			ini->cln_first_contact = SMC_REUSE_CONTACT;
1318			conn->lgr = lgr;
1319			rc = smc_lgr_register_conn(conn, false);
1320			write_unlock_bh(&lgr->conns_lock);
1321			if (!rc && delayed_work_pending(&lgr->free_work))
1322				cancel_delayed_work(&lgr->free_work);
1323			break;
1324		}
1325		write_unlock_bh(&lgr->conns_lock);
1326	}
1327	spin_unlock_bh(lgr_lock);
1328	if (rc)
1329		return rc;
1330
1331	if (role == SMC_CLNT && !ini->srv_first_contact &&
1332	    ini->cln_first_contact == SMC_FIRST_CONTACT) {
1333		/* Server reuses a link group, but Client wants to start
1334		 * a new one
1335		 * send out_of_sync decline, reason synchr. error
1336		 */
1337		return SMC_CLC_DECL_SYNCERR;
1338	}
1339
1340create:
1341	if (ini->cln_first_contact == SMC_FIRST_CONTACT) {
1342		rc = smc_lgr_create(smc, ini);
1343		if (rc)
1344			goto out;
1345		lgr = conn->lgr;
1346		write_lock_bh(&lgr->conns_lock);
1347		rc = smc_lgr_register_conn(conn, true);
1348		write_unlock_bh(&lgr->conns_lock);
1349		if (rc)
1350			goto out;
1351	}
1352	conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
1353	conn->local_tx_ctrl.len = SMC_WR_TX_SIZE;
1354	conn->urg_state = SMC_URG_READ;
1355	INIT_WORK(&smc->conn.abort_work, smc_conn_abort_work);
1356	if (ini->is_smcd) {
1357		conn->rx_off = sizeof(struct smcd_cdc_msg);
1358		smcd_cdc_rx_init(conn); /* init tasklet for this conn */
1359	} else {
1360		conn->rx_off = 0;
1361	}
1362#ifndef KERNEL_HAS_ATOMIC64
1363	spin_lock_init(&conn->acurs_lock);
1364#endif
1365
1366out:
1367	return rc;
1368}
1369
1370/* convert the RMB size into the compressed notation - minimum 16K.
1371 * In contrast to plain ilog2, this rounds towards the next power of 2,
1372 * so the socket application gets at least its desired sndbuf / rcvbuf size.
1373 */
1374static u8 smc_compress_bufsize(int size)
1375{
1376	u8 compressed;
1377
1378	if (size <= SMC_BUF_MIN_SIZE)
1379		return 0;
1380
1381	size = (size - 1) >> 14;
1382	compressed = ilog2(size) + 1;
1383	if (compressed >= SMC_RMBE_SIZES)
1384		compressed = SMC_RMBE_SIZES - 1;
1385	return compressed;
1386}
1387
1388/* convert the RMB size from compressed notation into integer */
1389int smc_uncompress_bufsize(u8 compressed)
1390{
1391	u32 size;
1392
1393	size = 0x00000001 << (((int)compressed) + 14);
1394	return (int)size;
1395}
1396
1397/* try to reuse a sndbuf or rmb description slot for a certain
1398 * buffer size; if not available, return NULL
1399 */
1400static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize,
1401					     struct mutex *lock,
1402					     struct list_head *buf_list)
1403{
1404	struct smc_buf_desc *buf_slot;
1405
1406	mutex_lock(lock);
1407	list_for_each_entry(buf_slot, buf_list, list) {
1408		if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
1409			mutex_unlock(lock);
1410			return buf_slot;
1411		}
1412	}
1413	mutex_unlock(lock);
1414	return NULL;
1415}
1416
1417/* one of the conditions for announcing a receiver's current window size is
1418 * that it "results in a minimum increase in the window size of 10% of the
1419 * receive buffer space" [RFC7609]
1420 */
1421static inline int smc_rmb_wnd_update_limit(int rmbe_size)
1422{
1423	return min_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
1424}
1425
1426/* map an rmb buf to a link */
1427static int smcr_buf_map_link(struct smc_buf_desc *buf_desc, bool is_rmb,
1428			     struct smc_link *lnk)
1429{
1430	int rc;
1431
1432	if (buf_desc->is_map_ib[lnk->link_idx])
1433		return 0;
1434
1435	rc = sg_alloc_table(&buf_desc->sgt[lnk->link_idx], 1, GFP_KERNEL);
1436	if (rc)
1437		return rc;
1438	sg_set_buf(buf_desc->sgt[lnk->link_idx].sgl,
1439		   buf_desc->cpu_addr, buf_desc->len);
1440
1441	/* map sg table to DMA address */
1442	rc = smc_ib_buf_map_sg(lnk, buf_desc,
1443			       is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
1444	/* SMC protocol depends on mapping to one DMA address only */
1445	if (rc != 1) {
1446		rc = -EAGAIN;
1447		goto free_table;
1448	}
1449
1450	/* create a new memory region for the RMB */
1451	if (is_rmb) {
1452		rc = smc_ib_get_memory_region(lnk->roce_pd,
1453					      IB_ACCESS_REMOTE_WRITE |
1454					      IB_ACCESS_LOCAL_WRITE,
1455					      buf_desc, lnk->link_idx);
1456		if (rc)
1457			goto buf_unmap;
1458		smc_ib_sync_sg_for_device(lnk, buf_desc, DMA_FROM_DEVICE);
1459	}
1460	buf_desc->is_map_ib[lnk->link_idx] = true;
1461	return 0;
1462
1463buf_unmap:
1464	smc_ib_buf_unmap_sg(lnk, buf_desc,
1465			    is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
1466free_table:
1467	sg_free_table(&buf_desc->sgt[lnk->link_idx]);
1468	return rc;
1469}
1470
1471/* register a new rmb on IB device,
1472 * must be called under lgr->llc_conf_mutex lock
1473 */
1474int smcr_link_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc)
1475{
1476	if (list_empty(&link->lgr->list))
1477		return -ENOLINK;
1478	if (!rmb_desc->is_reg_mr[link->link_idx]) {
1479		/* register memory region for new rmb */
1480		if (smc_wr_reg_send(link, rmb_desc->mr_rx[link->link_idx])) {
1481			rmb_desc->is_reg_err = true;
1482			return -EFAULT;
1483		}
1484		rmb_desc->is_reg_mr[link->link_idx] = true;
1485	}
1486	return 0;
1487}
1488
1489static int _smcr_buf_map_lgr(struct smc_link *lnk, struct mutex *lock,
1490			     struct list_head *lst, bool is_rmb)
1491{
1492	struct smc_buf_desc *buf_desc, *bf;
1493	int rc = 0;
1494
1495	mutex_lock(lock);
1496	list_for_each_entry_safe(buf_desc, bf, lst, list) {
1497		if (!buf_desc->used)
1498			continue;
1499		rc = smcr_buf_map_link(buf_desc, is_rmb, lnk);
1500		if (rc)
1501			goto out;
1502	}
1503out:
1504	mutex_unlock(lock);
1505	return rc;
1506}
1507
1508/* map all used buffers of lgr for a new link */
1509int smcr_buf_map_lgr(struct smc_link *lnk)
1510{
1511	struct smc_link_group *lgr = lnk->lgr;
1512	int i, rc = 0;
1513
1514	for (i = 0; i < SMC_RMBE_SIZES; i++) {
1515		rc = _smcr_buf_map_lgr(lnk, &lgr->rmbs_lock,
1516				       &lgr->rmbs[i], true);
1517		if (rc)
1518			return rc;
1519		rc = _smcr_buf_map_lgr(lnk, &lgr->sndbufs_lock,
1520				       &lgr->sndbufs[i], false);
1521		if (rc)
1522			return rc;
1523	}
1524	return 0;
1525}
1526
1527/* register all used buffers of lgr for a new link,
1528 * must be called under lgr->llc_conf_mutex lock
1529 */
1530int smcr_buf_reg_lgr(struct smc_link *lnk)
1531{
1532	struct smc_link_group *lgr = lnk->lgr;
1533	struct smc_buf_desc *buf_desc, *bf;
1534	int i, rc = 0;
1535
1536	mutex_lock(&lgr->rmbs_lock);
1537	for (i = 0; i < SMC_RMBE_SIZES; i++) {
1538		list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list) {
1539			if (!buf_desc->used)
1540				continue;
1541			rc = smcr_link_reg_rmb(lnk, buf_desc);
1542			if (rc)
1543				goto out;
1544		}
1545	}
1546out:
1547	mutex_unlock(&lgr->rmbs_lock);
1548	return rc;
1549}
1550
1551static struct smc_buf_desc *smcr_new_buf_create(struct smc_link_group *lgr,
1552						bool is_rmb, int bufsize)
1553{
1554	struct smc_buf_desc *buf_desc;
1555
1556	/* try to alloc a new buffer */
1557	buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
1558	if (!buf_desc)
1559		return ERR_PTR(-ENOMEM);
1560
1561	buf_desc->order = get_order(bufsize);
1562	buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN |
1563				      __GFP_NOMEMALLOC | __GFP_COMP |
1564				      __GFP_NORETRY | __GFP_ZERO,
1565				      buf_desc->order);
1566	if (!buf_desc->pages) {
1567		kfree(buf_desc);
1568		return ERR_PTR(-EAGAIN);
1569	}
1570	buf_desc->cpu_addr = (void *)page_address(buf_desc->pages);
1571	buf_desc->len = bufsize;
1572	return buf_desc;
1573}
1574
1575/* map buf_desc on all usable links,
1576 * unused buffers stay mapped as long as the link is up
1577 */
1578static int smcr_buf_map_usable_links(struct smc_link_group *lgr,
1579				     struct smc_buf_desc *buf_desc, bool is_rmb)
1580{
1581	int i, rc = 0;
1582
1583	/* protect against parallel link reconfiguration */
1584	mutex_lock(&lgr->llc_conf_mutex);
1585	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1586		struct smc_link *lnk = &lgr->lnk[i];
1587
1588		if (!smc_link_usable(lnk))
1589			continue;
1590		if (smcr_buf_map_link(buf_desc, is_rmb, lnk)) {
1591			rc = -ENOMEM;
1592			goto out;
1593		}
1594	}
1595out:
1596	mutex_unlock(&lgr->llc_conf_mutex);
1597	return rc;
1598}
1599
1600#define SMCD_DMBE_SIZES		7 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */
1601
1602static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr,
1603						bool is_dmb, int bufsize)
1604{
1605	struct smc_buf_desc *buf_desc;
1606	int rc;
1607
1608	if (smc_compress_bufsize(bufsize) > SMCD_DMBE_SIZES)
1609		return ERR_PTR(-EAGAIN);
1610
1611	/* try to alloc a new DMB */
1612	buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
1613	if (!buf_desc)
1614		return ERR_PTR(-ENOMEM);
1615	if (is_dmb) {
1616		rc = smc_ism_register_dmb(lgr, bufsize, buf_desc);
1617		if (rc) {
1618			kfree(buf_desc);
1619			return (rc == -ENOMEM) ? ERR_PTR(-EAGAIN) : ERR_PTR(rc);
 
 
 
 
1620		}
1621		buf_desc->pages = virt_to_page(buf_desc->cpu_addr);
1622		/* CDC header stored in buf. So, pretend it was smaller */
1623		buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg);
1624	} else {
1625		buf_desc->cpu_addr = kzalloc(bufsize, GFP_KERNEL |
1626					     __GFP_NOWARN | __GFP_NORETRY |
1627					     __GFP_NOMEMALLOC);
1628		if (!buf_desc->cpu_addr) {
1629			kfree(buf_desc);
1630			return ERR_PTR(-EAGAIN);
1631		}
1632		buf_desc->len = bufsize;
1633	}
1634	return buf_desc;
1635}
1636
1637static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb)
1638{
1639	struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM);
1640	struct smc_connection *conn = &smc->conn;
1641	struct smc_link_group *lgr = conn->lgr;
1642	struct list_head *buf_list;
1643	int bufsize, bufsize_short;
 
1644	struct mutex *lock;	/* lock buffer list */
1645	int sk_buf_size;
1646
1647	if (is_rmb)
1648		/* use socket recv buffer size (w/o overhead) as start value */
1649		sk_buf_size = smc->sk.sk_rcvbuf / 2;
1650	else
1651		/* use socket send buffer size (w/o overhead) as start value */
1652		sk_buf_size = smc->sk.sk_sndbuf / 2;
1653
1654	for (bufsize_short = smc_compress_bufsize(sk_buf_size);
1655	     bufsize_short >= 0; bufsize_short--) {
1656
1657		if (is_rmb) {
1658			lock = &lgr->rmbs_lock;
1659			buf_list = &lgr->rmbs[bufsize_short];
1660		} else {
1661			lock = &lgr->sndbufs_lock;
1662			buf_list = &lgr->sndbufs[bufsize_short];
1663		}
1664		bufsize = smc_uncompress_bufsize(bufsize_short);
1665		if ((1 << get_order(bufsize)) > SG_MAX_SINGLE_ALLOC)
1666			continue;
1667
1668		/* check for reusable slot in the link group */
1669		buf_desc = smc_buf_get_slot(bufsize_short, lock, buf_list);
1670		if (buf_desc) {
 
 
1671			memset(buf_desc->cpu_addr, 0, bufsize);
1672			break; /* found reusable slot */
1673		}
1674
1675		if (is_smcd)
1676			buf_desc = smcd_new_buf_create(lgr, is_rmb, bufsize);
1677		else
1678			buf_desc = smcr_new_buf_create(lgr, is_rmb, bufsize);
1679
1680		if (PTR_ERR(buf_desc) == -ENOMEM)
1681			break;
1682		if (IS_ERR(buf_desc))
 
 
 
 
1683			continue;
 
1684
 
 
1685		buf_desc->used = 1;
1686		mutex_lock(lock);
1687		list_add(&buf_desc->list, buf_list);
1688		mutex_unlock(lock);
1689		break; /* found */
1690	}
1691
1692	if (IS_ERR(buf_desc))
1693		return PTR_ERR(buf_desc);
1694
1695	if (!is_smcd) {
1696		if (smcr_buf_map_usable_links(lgr, buf_desc, is_rmb)) {
1697			smcr_buf_unuse(buf_desc, lgr);
1698			return -ENOMEM;
1699		}
1700	}
1701
1702	if (is_rmb) {
1703		conn->rmb_desc = buf_desc;
1704		conn->rmbe_size_short = bufsize_short;
1705		smc->sk.sk_rcvbuf = bufsize * 2;
1706		atomic_set(&conn->bytes_to_rcv, 0);
1707		conn->rmbe_update_limit =
1708			smc_rmb_wnd_update_limit(buf_desc->len);
1709		if (is_smcd)
1710			smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */
1711	} else {
1712		conn->sndbuf_desc = buf_desc;
1713		smc->sk.sk_sndbuf = bufsize * 2;
1714		atomic_set(&conn->sndbuf_space, bufsize);
1715	}
1716	return 0;
1717}
1718
1719void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn)
1720{
1721	if (!conn->lgr || conn->lgr->is_smcd || !smc_link_active(conn->lnk))
1722		return;
1723	smc_ib_sync_sg_for_cpu(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
1724}
1725
1726void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
1727{
1728	if (!conn->lgr || conn->lgr->is_smcd || !smc_link_active(conn->lnk))
1729		return;
1730	smc_ib_sync_sg_for_device(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
1731}
1732
1733void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
1734{
1735	int i;
1736
1737	if (!conn->lgr || conn->lgr->is_smcd)
1738		return;
1739	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1740		if (!smc_link_active(&conn->lgr->lnk[i]))
1741			continue;
1742		smc_ib_sync_sg_for_cpu(&conn->lgr->lnk[i], conn->rmb_desc,
1743				       DMA_FROM_DEVICE);
1744	}
1745}
1746
1747void smc_rmb_sync_sg_for_device(struct smc_connection *conn)
1748{
1749	int i;
1750
1751	if (!conn->lgr || conn->lgr->is_smcd)
1752		return;
1753	for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1754		if (!smc_link_active(&conn->lgr->lnk[i]))
1755			continue;
1756		smc_ib_sync_sg_for_device(&conn->lgr->lnk[i], conn->rmb_desc,
1757					  DMA_FROM_DEVICE);
1758	}
1759}
1760
1761/* create the send and receive buffer for an SMC socket;
1762 * receive buffers are called RMBs;
1763 * (even though the SMC protocol allows more than one RMB-element per RMB,
1764 * the Linux implementation uses just one RMB-element per RMB, i.e. uses an
1765 * extra RMB for every connection in a link group
1766 */
1767int smc_buf_create(struct smc_sock *smc, bool is_smcd)
1768{
1769	int rc;
1770
1771	/* create send buffer */
1772	rc = __smc_buf_create(smc, is_smcd, false);
1773	if (rc)
1774		return rc;
1775	/* create rmb */
1776	rc = __smc_buf_create(smc, is_smcd, true);
1777	if (rc) {
1778		mutex_lock(&smc->conn.lgr->sndbufs_lock);
1779		list_del(&smc->conn.sndbuf_desc->list);
1780		mutex_unlock(&smc->conn.lgr->sndbufs_lock);
1781		smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc);
1782		smc->conn.sndbuf_desc = NULL;
1783	}
1784	return rc;
1785}
1786
1787static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
1788{
1789	int i;
1790
1791	for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) {
1792		if (!test_and_set_bit(i, lgr->rtokens_used_mask))
1793			return i;
1794	}
1795	return -ENOSPC;
1796}
1797
1798static int smc_rtoken_find_by_link(struct smc_link_group *lgr, int lnk_idx,
1799				   u32 rkey)
1800{
1801	int i;
1802
1803	for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1804		if (test_bit(i, lgr->rtokens_used_mask) &&
1805		    lgr->rtokens[i][lnk_idx].rkey == rkey)
1806			return i;
1807	}
1808	return -ENOENT;
1809}
1810
1811/* set rtoken for a new link to an existing rmb */
1812void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
1813		    __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey)
1814{
1815	int rtok_idx;
1816
1817	rtok_idx = smc_rtoken_find_by_link(lgr, link_idx, ntohl(nw_rkey_known));
1818	if (rtok_idx == -ENOENT)
1819		return;
1820	lgr->rtokens[rtok_idx][link_idx_new].rkey = ntohl(nw_rkey);
1821	lgr->rtokens[rtok_idx][link_idx_new].dma_addr = be64_to_cpu(nw_vaddr);
1822}
1823
1824/* set rtoken for a new link whose link_id is given */
1825void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
1826		     __be64 nw_vaddr, __be32 nw_rkey)
1827{
1828	u64 dma_addr = be64_to_cpu(nw_vaddr);
1829	u32 rkey = ntohl(nw_rkey);
1830	bool found = false;
1831	int link_idx;
1832
1833	for (link_idx = 0; link_idx < SMC_LINKS_PER_LGR_MAX; link_idx++) {
1834		if (lgr->lnk[link_idx].link_id == link_id) {
1835			found = true;
1836			break;
1837		}
1838	}
1839	if (!found)
1840		return;
1841	lgr->rtokens[rtok_idx][link_idx].rkey = rkey;
1842	lgr->rtokens[rtok_idx][link_idx].dma_addr = dma_addr;
1843}
1844
1845/* add a new rtoken from peer */
1846int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey)
1847{
1848	struct smc_link_group *lgr = smc_get_lgr(lnk);
1849	u64 dma_addr = be64_to_cpu(nw_vaddr);
1850	u32 rkey = ntohl(nw_rkey);
1851	int i;
1852
1853	for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1854		if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
1855		    lgr->rtokens[i][lnk->link_idx].dma_addr == dma_addr &&
1856		    test_bit(i, lgr->rtokens_used_mask)) {
1857			/* already in list */
1858			return i;
1859		}
1860	}
1861	i = smc_rmb_reserve_rtoken_idx(lgr);
1862	if (i < 0)
1863		return i;
1864	lgr->rtokens[i][lnk->link_idx].rkey = rkey;
1865	lgr->rtokens[i][lnk->link_idx].dma_addr = dma_addr;
1866	return i;
1867}
1868
1869/* delete an rtoken from all links */
1870int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey)
1871{
1872	struct smc_link_group *lgr = smc_get_lgr(lnk);
1873	u32 rkey = ntohl(nw_rkey);
1874	int i, j;
1875
1876	for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1877		if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
1878		    test_bit(i, lgr->rtokens_used_mask)) {
1879			for (j = 0; j < SMC_LINKS_PER_LGR_MAX; j++) {
1880				lgr->rtokens[i][j].rkey = 0;
1881				lgr->rtokens[i][j].dma_addr = 0;
1882			}
1883			clear_bit(i, lgr->rtokens_used_mask);
1884			return 0;
1885		}
1886	}
1887	return -ENOENT;
1888}
1889
1890/* save rkey and dma_addr received from peer during clc handshake */
1891int smc_rmb_rtoken_handling(struct smc_connection *conn,
1892			    struct smc_link *lnk,
1893			    struct smc_clc_msg_accept_confirm *clc)
1894{
1895	conn->rtoken_idx = smc_rtoken_add(lnk, clc->rmb_dma_addr,
1896					  clc->rmb_rkey);
1897	if (conn->rtoken_idx < 0)
1898		return conn->rtoken_idx;
1899	return 0;
1900}
1901
1902static void smc_core_going_away(void)
1903{
1904	struct smc_ib_device *smcibdev;
1905	struct smcd_dev *smcd;
1906
1907	mutex_lock(&smc_ib_devices.mutex);
1908	list_for_each_entry(smcibdev, &smc_ib_devices.list, list) {
1909		int i;
1910
1911		for (i = 0; i < SMC_MAX_PORTS; i++)
1912			set_bit(i, smcibdev->ports_going_away);
1913	}
1914	mutex_unlock(&smc_ib_devices.mutex);
1915
1916	mutex_lock(&smcd_dev_list.mutex);
1917	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
1918		smcd->going_away = 1;
1919	}
1920	mutex_unlock(&smcd_dev_list.mutex);
1921}
1922
1923/* Clean up all SMC link groups */
1924static void smc_lgrs_shutdown(void)
1925{
1926	struct smcd_dev *smcd;
1927
1928	smc_core_going_away();
1929
1930	smc_smcr_terminate_all(NULL);
1931
1932	mutex_lock(&smcd_dev_list.mutex);
1933	list_for_each_entry(smcd, &smcd_dev_list.list, list)
1934		smc_smcd_terminate_all(smcd);
1935	mutex_unlock(&smcd_dev_list.mutex);
1936}
1937
1938static int smc_core_reboot_event(struct notifier_block *this,
1939				 unsigned long event, void *ptr)
1940{
1941	smc_lgrs_shutdown();
1942	smc_ib_unregister_client();
1943	return 0;
1944}
1945
1946static struct notifier_block smc_reboot_notifier = {
1947	.notifier_call = smc_core_reboot_event,
1948};
1949
1950int __init smc_core_init(void)
1951{
1952	return register_reboot_notifier(&smc_reboot_notifier);
1953}
1954
1955/* Called (from smc_exit) when module is removed */
1956void smc_core_exit(void)
1957{
1958	unregister_reboot_notifier(&smc_reboot_notifier);
1959	smc_lgrs_shutdown();
1960}