net/smc/smc_core.c

   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 <linux/list.h>
  20 #include <linux/smc.h>
  21 #include <net/tcp.h>
  22 #include <net/sock.h>
  23 #include <rdma/ib_verbs.h>
  24 #include <rdma/ib_cache.h>
  25
  26 #include "smc.h"
  27 #include "smc_clc.h"
  28 #include "smc_core.h"
  29 #include "smc_ib.h"
  30 #include "smc_wr.h"
  31 #include "smc_llc.h"
  32 #include "smc_cdc.h"
  33 #include "smc_close.h"
  34 #include "smc_ism.h"
  35 #include "smc_netlink.h"
  36 #include "smc_stats.h"
  37 #include "smc_tracepoint.h"
  38
  39 #define SMC_LGR_NUM_INCR                256
  40 #define SMC_LGR_FREE_DELAY_SERV         (600 * HZ)
  41 #define SMC_LGR_FREE_DELAY_CLNT         (SMC_LGR_FREE_DELAY_SERV + 10 * HZ)
  42
  43 struct smc_lgr_list smc_lgr_list = {    /* established link groups */
  44         .lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
  45         .list = LIST_HEAD_INIT(smc_lgr_list.list),
  46         .num = 0,
  47 };
  48
  49 static atomic_t lgr_cnt = ATOMIC_INIT(0); /* number of existing link groups */
  50 static DECLARE_WAIT_QUEUE_HEAD(lgrs_deleted);
  51
  52 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
  53                          struct smc_buf_desc *buf_desc);
  54 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft);
  55
  56 static void smc_link_down_work(struct work_struct *work);
  57
  58 /* return head of link group list and its lock for a given link group */
  59 static inline struct list_head *smc_lgr_list_head(struct smc_link_group *lgr,
  60                                                   spinlock_t **lgr_lock)
  61 {
  62         if (lgr->is_smcd) {
  63                 *lgr_lock = &lgr->smcd->lgr_lock;
  64                 return &lgr->smcd->lgr_list;
  65         }
  66
  67         *lgr_lock = &smc_lgr_list.lock;
  68         return &smc_lgr_list.list;
  69 }
  70
  71 static void smc_ibdev_cnt_inc(struct smc_link *lnk)
  72 {
  73         atomic_inc(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
  74 }
  75
  76 static void smc_ibdev_cnt_dec(struct smc_link *lnk)
  77 {
  78         atomic_dec(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
  79 }
  80
  81 static void smc_lgr_schedule_free_work(struct smc_link_group *lgr)
  82 {
  83         /* client link group creation always follows the server link group
  84          * creation. For client use a somewhat higher removal delay time,
  85          * otherwise there is a risk of out-of-sync link groups.
  86          */
  87         if (!lgr->freeing) {
  88                 mod_delayed_work(system_wq, &lgr->free_work,
  89                                  (!lgr->is_smcd && lgr->role == SMC_CLNT) ?
  90                                                 SMC_LGR_FREE_DELAY_CLNT :
  91                                                 SMC_LGR_FREE_DELAY_SERV);
  92         }
  93 }
  94
  95 /* Register connection's alert token in our lookup structure.
  96  * To use rbtrees we have to implement our own insert core.
  97  * Requires @conns_lock
  98  * @smc         connection to register
  99  * Returns 0 on success, != otherwise.
 100  */
 101 static void smc_lgr_add_alert_token(struct smc_connection *conn)
 102 {
 103         struct rb_node **link, *parent = NULL;
 104         u32 token = conn->alert_token_local;
 105
 106         link = &conn->lgr->conns_all.rb_node;
 107         while (*link) {
 108                 struct smc_connection *cur = rb_entry(*link,
 109                                         struct smc_connection, alert_node);
 110
 111                 parent = *link;
 112                 if (cur->alert_token_local > token)
 113                         link = &parent->rb_left;
 114                 else
 115                         link = &parent->rb_right;
 116         }
 117         /* Put the new node there */
 118         rb_link_node(&conn->alert_node, parent, link);
 119         rb_insert_color(&conn->alert_node, &conn->lgr->conns_all);
 120 }
 121
 122 /* assign an SMC-R link to the connection */
 123 static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first)
 124 {
 125         enum smc_link_state expected = first ? SMC_LNK_ACTIVATING :
 126                                        SMC_LNK_ACTIVE;
 127         int i, j;
 128
 129         /* do link balancing */
 130         conn->lnk = NULL;       /* reset conn->lnk first */
 131         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 132                 struct smc_link *lnk = &conn->lgr->lnk[i];
 133
 134                 if (lnk->state != expected || lnk->link_is_asym)
 135                         continue;
 136                 if (conn->lgr->role == SMC_CLNT) {
 137                         conn->lnk = lnk; /* temporary, SMC server assigns link*/
 138                         break;
 139                 }
 140                 if (conn->lgr->conns_num % 2) {
 141                         for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) {
 142                                 struct smc_link *lnk2;
 143
 144                                 lnk2 = &conn->lgr->lnk[j];
 145                                 if (lnk2->state == expected &&
 146                                     !lnk2->link_is_asym) {
 147                                         conn->lnk = lnk2;
 148                                         break;
 149                                 }
 150                         }
 151                 }
 152                 if (!conn->lnk)
 153                         conn->lnk = lnk;
 154                 break;
 155         }
 156         if (!conn->lnk)
 157                 return SMC_CLC_DECL_NOACTLINK;
 158         atomic_inc(&conn->lnk->conn_cnt);
 159         return 0;
 160 }
 161
 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.
 166  */
 167 static int smc_lgr_register_conn(struct smc_connection *conn, bool first)
 168 {
 169         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 170         static atomic_t nexttoken = ATOMIC_INIT(0);
 171         int rc;
 172
 173         if (!conn->lgr->is_smcd) {
 174                 rc = smcr_lgr_conn_assign_link(conn, first);
 175                 if (rc) {
 176                         conn->lgr = NULL;
 177                         return rc;
 178                 }
 179         }
 180         /* find a new alert_token_local value not yet used by some connection
 181          * in this link group
 182          */
 183         sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */
 184         while (!conn->alert_token_local) {
 185                 conn->alert_token_local = atomic_inc_return(&nexttoken);
 186                 if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr))
 187                         conn->alert_token_local = 0;
 188         }
 189         smc_lgr_add_alert_token(conn);
 190         conn->lgr->conns_num++;
 191         return 0;
 192 }
 193
 194 /* Unregister connection and reset the alert token of the given connection<
 195  */
 196 static void __smc_lgr_unregister_conn(struct smc_connection *conn)
 197 {
 198         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 199         struct smc_link_group *lgr = conn->lgr;
 200
 201         rb_erase(&conn->alert_node, &lgr->conns_all);
 202         if (conn->lnk)
 203                 atomic_dec(&conn->lnk->conn_cnt);
 204         lgr->conns_num--;
 205         conn->alert_token_local = 0;
 206         sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
 207 }
 208
 209 /* Unregister connection from lgr
 210  */
 211 static void smc_lgr_unregister_conn(struct smc_connection *conn)
 212 {
 213         struct smc_link_group *lgr = conn->lgr;
 214
 215         if (!smc_conn_lgr_valid(conn))
 216                 return;
 217         write_lock_bh(&lgr->conns_lock);
 218         if (conn->alert_token_local) {
 219                 __smc_lgr_unregister_conn(conn);
 220         }
 221         write_unlock_bh(&lgr->conns_lock);
 222 }
 223
 224 int smc_nl_get_sys_info(struct sk_buff *skb, struct netlink_callback *cb)
 225 {
 226         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 227         char hostname[SMC_MAX_HOSTNAME_LEN + 1];
 228         char smc_seid[SMC_MAX_EID_LEN + 1];
 229         struct nlattr *attrs;
 230         u8 *seid = NULL;
 231         u8 *host = NULL;
 232         void *nlh;
 233
 234         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 235                           &smc_gen_nl_family, NLM_F_MULTI,
 236                           SMC_NETLINK_GET_SYS_INFO);
 237         if (!nlh)
 238                 goto errmsg;
 239         if (cb_ctx->pos[0])
 240                 goto errout;
 241         attrs = nla_nest_start(skb, SMC_GEN_SYS_INFO);
 242         if (!attrs)
 243                 goto errout;
 244         if (nla_put_u8(skb, SMC_NLA_SYS_VER, SMC_V2))
 245                 goto errattr;
 246         if (nla_put_u8(skb, SMC_NLA_SYS_REL, SMC_RELEASE))
 247                 goto errattr;
 248         if (nla_put_u8(skb, SMC_NLA_SYS_IS_ISM_V2, smc_ism_is_v2_capable()))
 249                 goto errattr;
 250         if (nla_put_u8(skb, SMC_NLA_SYS_IS_SMCR_V2, true))
 251                 goto errattr;
 252         smc_clc_get_hostname(&host);
 253         if (host) {
 254                 memcpy(hostname, host, SMC_MAX_HOSTNAME_LEN);
 255                 hostname[SMC_MAX_HOSTNAME_LEN] = 0;
 256                 if (nla_put_string(skb, SMC_NLA_SYS_LOCAL_HOST, hostname))
 257                         goto errattr;
 258         }
 259         if (smc_ism_is_v2_capable()) {
 260                 smc_ism_get_system_eid(&seid);
 261                 memcpy(smc_seid, seid, SMC_MAX_EID_LEN);
 262                 smc_seid[SMC_MAX_EID_LEN] = 0;
 263                 if (nla_put_string(skb, SMC_NLA_SYS_SEID, smc_seid))
 264                         goto errattr;
 265         }
 266         nla_nest_end(skb, attrs);
 267         genlmsg_end(skb, nlh);
 268         cb_ctx->pos[0] = 1;
 269         return skb->len;
 270
 271 errattr:
 272         nla_nest_cancel(skb, attrs);
 273 errout:
 274         genlmsg_cancel(skb, nlh);
 275 errmsg:
 276         return skb->len;
 277 }
 278
 279 /* Fill SMC_NLA_LGR_D_V2_COMMON/SMC_NLA_LGR_R_V2_COMMON nested attributes */
 280 static int smc_nl_fill_lgr_v2_common(struct smc_link_group *lgr,
 281                                      struct sk_buff *skb,
 282                                      struct netlink_callback *cb,
 283                                      struct nlattr *v2_attrs)
 284 {
 285         char smc_host[SMC_MAX_HOSTNAME_LEN + 1];
 286         char smc_eid[SMC_MAX_EID_LEN + 1];
 287
 288         if (nla_put_u8(skb, SMC_NLA_LGR_V2_VER, lgr->smc_version))
 289                 goto errv2attr;
 290         if (nla_put_u8(skb, SMC_NLA_LGR_V2_REL, lgr->peer_smc_release))
 291                 goto errv2attr;
 292         if (nla_put_u8(skb, SMC_NLA_LGR_V2_OS, lgr->peer_os))
 293                 goto errv2attr;
 294         memcpy(smc_host, lgr->peer_hostname, SMC_MAX_HOSTNAME_LEN);
 295         smc_host[SMC_MAX_HOSTNAME_LEN] = 0;
 296         if (nla_put_string(skb, SMC_NLA_LGR_V2_PEER_HOST, smc_host))
 297                 goto errv2attr;
 298         memcpy(smc_eid, lgr->negotiated_eid, SMC_MAX_EID_LEN);
 299         smc_eid[SMC_MAX_EID_LEN] = 0;
 300         if (nla_put_string(skb, SMC_NLA_LGR_V2_NEG_EID, smc_eid))
 301                 goto errv2attr;
 302
 303         nla_nest_end(skb, v2_attrs);
 304         return 0;
 305
 306 errv2attr:
 307         nla_nest_cancel(skb, v2_attrs);
 308         return -EMSGSIZE;
 309 }
 310
 311 static int smc_nl_fill_smcr_lgr_v2(struct smc_link_group *lgr,
 312                                    struct sk_buff *skb,
 313                                    struct netlink_callback *cb)
 314 {
 315         struct nlattr *v2_attrs;
 316
 317         v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2);
 318         if (!v2_attrs)
 319                 goto errattr;
 320         if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_DIRECT, !lgr->uses_gateway))
 321                 goto errv2attr;
 322         if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_MAX_CONNS, lgr->max_conns))
 323                 goto errv2attr;
 324         if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_MAX_LINKS, lgr->max_links))
 325                 goto errv2attr;
 326
 327         nla_nest_end(skb, v2_attrs);
 328         return 0;
 329
 330 errv2attr:
 331         nla_nest_cancel(skb, v2_attrs);
 332 errattr:
 333         return -EMSGSIZE;
 334 }
 335
 336 static int smc_nl_fill_lgr(struct smc_link_group *lgr,
 337                            struct sk_buff *skb,
 338                            struct netlink_callback *cb)
 339 {
 340         char smc_target[SMC_MAX_PNETID_LEN + 1];
 341         struct nlattr *attrs, *v2_attrs;
 342
 343         attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCR);
 344         if (!attrs)
 345                 goto errout;
 346
 347         if (nla_put_u32(skb, SMC_NLA_LGR_R_ID, *((u32 *)&lgr->id)))
 348                 goto errattr;
 349         if (nla_put_u32(skb, SMC_NLA_LGR_R_CONNS_NUM, lgr->conns_num))
 350                 goto errattr;
 351         if (nla_put_u8(skb, SMC_NLA_LGR_R_ROLE, lgr->role))
 352                 goto errattr;
 353         if (nla_put_u8(skb, SMC_NLA_LGR_R_TYPE, lgr->type))
 354                 goto errattr;
 355         if (nla_put_u8(skb, SMC_NLA_LGR_R_BUF_TYPE, lgr->buf_type))
 356                 goto errattr;
 357         if (nla_put_u8(skb, SMC_NLA_LGR_R_VLAN_ID, lgr->vlan_id))
 358                 goto errattr;
 359         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_R_NET_COOKIE,
 360                               lgr->net->net_cookie, SMC_NLA_LGR_R_PAD))
 361                 goto errattr;
 362         memcpy(smc_target, lgr->pnet_id, SMC_MAX_PNETID_LEN);
 363         smc_target[SMC_MAX_PNETID_LEN] = 0;
 364         if (nla_put_string(skb, SMC_NLA_LGR_R_PNETID, smc_target))
 365                 goto errattr;
 366         if (lgr->smc_version > SMC_V1) {
 367                 v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2_COMMON);
 368                 if (!v2_attrs)
 369                         goto errattr;
 370                 if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
 371                         goto errattr;
 372                 if (smc_nl_fill_smcr_lgr_v2(lgr, skb, cb))
 373                         goto errattr;
 374         }
 375
 376         nla_nest_end(skb, attrs);
 377         return 0;
 378 errattr:
 379         nla_nest_cancel(skb, attrs);
 380 errout:
 381         return -EMSGSIZE;
 382 }
 383
 384 static int smc_nl_fill_lgr_link(struct smc_link_group *lgr,
 385                                 struct smc_link *link,
 386                                 struct sk_buff *skb,
 387                                 struct netlink_callback *cb)
 388 {
 389         char smc_ibname[IB_DEVICE_NAME_MAX];
 390         u8 smc_gid_target[41];
 391         struct nlattr *attrs;
 392         u32 link_uid = 0;
 393         void *nlh;
 394
 395         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 396                           &smc_gen_nl_family, NLM_F_MULTI,
 397                           SMC_NETLINK_GET_LINK_SMCR);
 398         if (!nlh)
 399                 goto errmsg;
 400
 401         attrs = nla_nest_start(skb, SMC_GEN_LINK_SMCR);
 402         if (!attrs)
 403                 goto errout;
 404
 405         if (nla_put_u8(skb, SMC_NLA_LINK_ID, link->link_id))
 406                 goto errattr;
 407         if (nla_put_u32(skb, SMC_NLA_LINK_STATE, link->state))
 408                 goto errattr;
 409         if (nla_put_u32(skb, SMC_NLA_LINK_CONN_CNT,
 410                         atomic_read(&link->conn_cnt)))
 411                 goto errattr;
 412         if (nla_put_u8(skb, SMC_NLA_LINK_IB_PORT, link->ibport))
 413                 goto errattr;
 414         if (nla_put_u32(skb, SMC_NLA_LINK_NET_DEV, link->ndev_ifidx))
 415                 goto errattr;
 416         snprintf(smc_ibname, sizeof(smc_ibname), "%s", link->ibname);
 417         if (nla_put_string(skb, SMC_NLA_LINK_IB_DEV, smc_ibname))
 418                 goto errattr;
 419         memcpy(&link_uid, link->link_uid, sizeof(link_uid));
 420         if (nla_put_u32(skb, SMC_NLA_LINK_UID, link_uid))
 421                 goto errattr;
 422         memcpy(&link_uid, link->peer_link_uid, sizeof(link_uid));
 423         if (nla_put_u32(skb, SMC_NLA_LINK_PEER_UID, link_uid))
 424                 goto errattr;
 425         memset(smc_gid_target, 0, sizeof(smc_gid_target));
 426         smc_gid_be16_convert(smc_gid_target, link->gid);
 427         if (nla_put_string(skb, SMC_NLA_LINK_GID, smc_gid_target))
 428                 goto errattr;
 429         memset(smc_gid_target, 0, sizeof(smc_gid_target));
 430         smc_gid_be16_convert(smc_gid_target, link->peer_gid);
 431         if (nla_put_string(skb, SMC_NLA_LINK_PEER_GID, smc_gid_target))
 432                 goto errattr;
 433
 434         nla_nest_end(skb, attrs);
 435         genlmsg_end(skb, nlh);
 436         return 0;
 437 errattr:
 438         nla_nest_cancel(skb, attrs);
 439 errout:
 440         genlmsg_cancel(skb, nlh);
 441 errmsg:
 442         return -EMSGSIZE;
 443 }
 444
 445 static int smc_nl_handle_lgr(struct smc_link_group *lgr,
 446                              struct sk_buff *skb,
 447                              struct netlink_callback *cb,
 448                              bool list_links)
 449 {
 450         void *nlh;
 451         int i;
 452
 453         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 454                           &smc_gen_nl_family, NLM_F_MULTI,
 455                           SMC_NETLINK_GET_LGR_SMCR);
 456         if (!nlh)
 457                 goto errmsg;
 458         if (smc_nl_fill_lgr(lgr, skb, cb))
 459                 goto errout;
 460
 461         genlmsg_end(skb, nlh);
 462         if (!list_links)
 463                 goto out;
 464         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 465                 if (!smc_link_usable(&lgr->lnk[i]))
 466                         continue;
 467                 if (smc_nl_fill_lgr_link(lgr, &lgr->lnk[i], skb, cb))
 468                         goto errout;
 469         }
 470 out:
 471         return 0;
 472
 473 errout:
 474         genlmsg_cancel(skb, nlh);
 475 errmsg:
 476         return -EMSGSIZE;
 477 }
 478
 479 static void smc_nl_fill_lgr_list(struct smc_lgr_list *smc_lgr,
 480                                  struct sk_buff *skb,
 481                                  struct netlink_callback *cb,
 482                                  bool list_links)
 483 {
 484         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 485         struct smc_link_group *lgr;
 486         int snum = cb_ctx->pos[0];
 487         int num = 0;
 488
 489         spin_lock_bh(&smc_lgr->lock);
 490         list_for_each_entry(lgr, &smc_lgr->list, list) {
 491                 if (num < snum)
 492                         goto next;
 493                 if (smc_nl_handle_lgr(lgr, skb, cb, list_links))
 494                         goto errout;
 495 next:
 496                 num++;
 497         }
 498 errout:
 499         spin_unlock_bh(&smc_lgr->lock);
 500         cb_ctx->pos[0] = num;
 501 }
 502
 503 static int smc_nl_fill_smcd_lgr(struct smc_link_group *lgr,
 504                                 struct sk_buff *skb,
 505                                 struct netlink_callback *cb)
 506 {
 507         char smc_pnet[SMC_MAX_PNETID_LEN + 1];
 508         struct smcd_dev *smcd = lgr->smcd;
 509         struct smcd_gid smcd_gid;
 510         struct nlattr *attrs;
 511         void *nlh;
 512
 513         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 514                           &smc_gen_nl_family, NLM_F_MULTI,
 515                           SMC_NETLINK_GET_LGR_SMCD);
 516         if (!nlh)
 517                 goto errmsg;
 518
 519         attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCD);
 520         if (!attrs)
 521                 goto errout;
 522
 523         if (nla_put_u32(skb, SMC_NLA_LGR_D_ID, *((u32 *)&lgr->id)))
 524                 goto errattr;
 525         smcd->ops->get_local_gid(smcd, &smcd_gid);
 526         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_GID,
 527                               smcd_gid.gid, SMC_NLA_LGR_D_PAD))
 528                 goto errattr;
 529         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_EXT_GID,
 530                               smcd_gid.gid_ext, SMC_NLA_LGR_D_PAD))
 531                 goto errattr;
 532         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_GID, lgr->peer_gid.gid,
 533                               SMC_NLA_LGR_D_PAD))
 534                 goto errattr;
 535         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_EXT_GID,
 536                               lgr->peer_gid.gid_ext, SMC_NLA_LGR_D_PAD))
 537                 goto errattr;
 538         if (nla_put_u8(skb, SMC_NLA_LGR_D_VLAN_ID, lgr->vlan_id))
 539                 goto errattr;
 540         if (nla_put_u32(skb, SMC_NLA_LGR_D_CONNS_NUM, lgr->conns_num))
 541                 goto errattr;
 542         if (nla_put_u32(skb, SMC_NLA_LGR_D_CHID, smc_ism_get_chid(lgr->smcd)))
 543                 goto errattr;
 544         memcpy(smc_pnet, lgr->smcd->pnetid, SMC_MAX_PNETID_LEN);
 545         smc_pnet[SMC_MAX_PNETID_LEN] = 0;
 546         if (nla_put_string(skb, SMC_NLA_LGR_D_PNETID, smc_pnet))
 547                 goto errattr;
 548         if (lgr->smc_version > SMC_V1) {
 549                 struct nlattr *v2_attrs;
 550
 551                 v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_D_V2_COMMON);
 552                 if (!v2_attrs)
 553                         goto errattr;
 554                 if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
 555                         goto errattr;
 556         }
 557         nla_nest_end(skb, attrs);
 558         genlmsg_end(skb, nlh);
 559         return 0;
 560
 561 errattr:
 562         nla_nest_cancel(skb, attrs);
 563 errout:
 564         genlmsg_cancel(skb, nlh);
 565 errmsg:
 566         return -EMSGSIZE;
 567 }
 568
 569 static int smc_nl_handle_smcd_lgr(struct smcd_dev *dev,
 570                                   struct sk_buff *skb,
 571                                   struct netlink_callback *cb)
 572 {
 573         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 574         struct smc_link_group *lgr;
 575         int snum = cb_ctx->pos[1];
 576         int rc = 0, num = 0;
 577
 578         spin_lock_bh(&dev->lgr_lock);
 579         list_for_each_entry(lgr, &dev->lgr_list, list) {
 580                 if (!lgr->is_smcd)
 581                         continue;
 582                 if (num < snum)
 583                         goto next;
 584                 rc = smc_nl_fill_smcd_lgr(lgr, skb, cb);
 585                 if (rc)
 586                         goto errout;
 587 next:
 588                 num++;
 589         }
 590 errout:
 591         spin_unlock_bh(&dev->lgr_lock);
 592         cb_ctx->pos[1] = num;
 593         return rc;
 594 }
 595
 596 static int smc_nl_fill_smcd_dev(struct smcd_dev_list *dev_list,
 597                                 struct sk_buff *skb,
 598                                 struct netlink_callback *cb)
 599 {
 600         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 601         struct smcd_dev *smcd_dev;
 602         int snum = cb_ctx->pos[0];
 603         int rc = 0, num = 0;
 604
 605         mutex_lock(&dev_list->mutex);
 606         list_for_each_entry(smcd_dev, &dev_list->list, list) {
 607                 if (list_empty(&smcd_dev->lgr_list))
 608                         continue;
 609                 if (num < snum)
 610                         goto next;
 611                 rc = smc_nl_handle_smcd_lgr(smcd_dev, skb, cb);
 612                 if (rc)
 613                         goto errout;
 614 next:
 615                 num++;
 616         }
 617 errout:
 618         mutex_unlock(&dev_list->mutex);
 619         cb_ctx->pos[0] = num;
 620         return rc;
 621 }
 622
 623 int smcr_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
 624 {
 625         bool list_links = false;
 626
 627         smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
 628         return skb->len;
 629 }
 630
 631 int smcr_nl_get_link(struct sk_buff *skb, struct netlink_callback *cb)
 632 {
 633         bool list_links = true;
 634
 635         smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
 636         return skb->len;
 637 }
 638
 639 int smcd_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
 640 {
 641         smc_nl_fill_smcd_dev(&smcd_dev_list, skb, cb);
 642         return skb->len;
 643 }
 644
 645 void smc_lgr_cleanup_early(struct smc_link_group *lgr)
 646 {
 647         spinlock_t *lgr_lock;
 648
 649         if (!lgr)
 650                 return;
 651
 652         smc_lgr_list_head(lgr, &lgr_lock);
 653         spin_lock_bh(lgr_lock);
 654         /* do not use this link group for new connections */
 655         if (!list_empty(&lgr->list))
 656                 list_del_init(&lgr->list);
 657         spin_unlock_bh(lgr_lock);
 658         __smc_lgr_terminate(lgr, true);
 659 }
 660
 661 static void smcr_lgr_link_deactivate_all(struct smc_link_group *lgr)
 662 {
 663         int i;
 664
 665         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 666                 struct smc_link *lnk = &lgr->lnk[i];
 667
 668                 if (smc_link_sendable(lnk))
 669                         lnk->state = SMC_LNK_INACTIVE;
 670         }
 671         wake_up_all(&lgr->llc_msg_waiter);
 672         wake_up_all(&lgr->llc_flow_waiter);
 673 }
 674
 675 static void smc_lgr_free(struct smc_link_group *lgr);
 676
 677 static void smc_lgr_free_work(struct work_struct *work)
 678 {
 679         struct smc_link_group *lgr = container_of(to_delayed_work(work),
 680                                                   struct smc_link_group,
 681                                                   free_work);
 682         spinlock_t *lgr_lock;
 683         bool conns;
 684
 685         smc_lgr_list_head(lgr, &lgr_lock);
 686         spin_lock_bh(lgr_lock);
 687         if (lgr->freeing) {
 688                 spin_unlock_bh(lgr_lock);
 689                 return;
 690         }
 691         read_lock_bh(&lgr->conns_lock);
 692         conns = RB_EMPTY_ROOT(&lgr->conns_all);
 693         read_unlock_bh(&lgr->conns_lock);
 694         if (!conns) { /* number of lgr connections is no longer zero */
 695                 spin_unlock_bh(lgr_lock);
 696                 return;
 697         }
 698         list_del_init(&lgr->list); /* remove from smc_lgr_list */
 699         lgr->freeing = 1; /* this instance does the freeing, no new schedule */
 700         spin_unlock_bh(lgr_lock);
 701         cancel_delayed_work(&lgr->free_work);
 702
 703         if (!lgr->is_smcd && !lgr->terminating)
 704                 smc_llc_send_link_delete_all(lgr, true,
 705                                              SMC_LLC_DEL_PROG_INIT_TERM);
 706         if (lgr->is_smcd && !lgr->terminating)
 707                 smc_ism_signal_shutdown(lgr);
 708         if (!lgr->is_smcd)
 709                 smcr_lgr_link_deactivate_all(lgr);
 710         smc_lgr_free(lgr);
 711 }
 712
 713 static void smc_lgr_terminate_work(struct work_struct *work)
 714 {
 715         struct smc_link_group *lgr = container_of(work, struct smc_link_group,
 716                                                   terminate_work);
 717
 718         __smc_lgr_terminate(lgr, true);
 719 }
 720
 721 /* return next unique link id for the lgr */
 722 static u8 smcr_next_link_id(struct smc_link_group *lgr)
 723 {
 724         u8 link_id;
 725         int i;
 726
 727         while (1) {
 728 again:
 729                 link_id = ++lgr->next_link_id;
 730                 if (!link_id)   /* skip zero as link_id */
 731                         link_id = ++lgr->next_link_id;
 732                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 733                         if (smc_link_usable(&lgr->lnk[i]) &&
 734                             lgr->lnk[i].link_id == link_id)
 735                                 goto again;
 736                 }
 737                 break;
 738         }
 739         return link_id;
 740 }
 741
 742 static void smcr_copy_dev_info_to_link(struct smc_link *link)
 743 {
 744         struct smc_ib_device *smcibdev = link->smcibdev;
 745
 746         snprintf(link->ibname, sizeof(link->ibname), "%s",
 747                  smcibdev->ibdev->name);
 748         link->ndev_ifidx = smcibdev->ndev_ifidx[link->ibport - 1];
 749 }
 750
 751 int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
 752                    u8 link_idx, struct smc_init_info *ini)
 753 {
 754         struct smc_ib_device *smcibdev;
 755         u8 rndvec[3];
 756         int rc;
 757
 758         if (lgr->smc_version == SMC_V2) {
 759                 lnk->smcibdev = ini->smcrv2.ib_dev_v2;
 760                 lnk->ibport = ini->smcrv2.ib_port_v2;
 761         } else {
 762                 lnk->smcibdev = ini->ib_dev;
 763                 lnk->ibport = ini->ib_port;
 764         }
 765         get_device(&lnk->smcibdev->ibdev->dev);
 766         atomic_inc(&lnk->smcibdev->lnk_cnt);
 767         refcount_set(&lnk->refcnt, 1); /* link refcnt is set to 1 */
 768         lnk->clearing = 0;
 769         lnk->path_mtu = lnk->smcibdev->pattr[lnk->ibport - 1].active_mtu;
 770         lnk->link_id = smcr_next_link_id(lgr);
 771         lnk->lgr = lgr;
 772         smc_lgr_hold(lgr); /* lgr_put in smcr_link_clear() */
 773         lnk->link_idx = link_idx;
 774         lnk->wr_rx_id_compl = 0;
 775         smc_ibdev_cnt_inc(lnk);
 776         smcr_copy_dev_info_to_link(lnk);
 777         atomic_set(&lnk->conn_cnt, 0);
 778         smc_llc_link_set_uid(lnk);
 779         INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
 780         if (!lnk->smcibdev->initialized) {
 781                 rc = (int)smc_ib_setup_per_ibdev(lnk->smcibdev);
 782                 if (rc)
 783                         goto out;
 784         }
 785         get_random_bytes(rndvec, sizeof(rndvec));
 786         lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) +
 787                 (rndvec[2] << 16);
 788         rc = smc_ib_determine_gid(lnk->smcibdev, lnk->ibport,
 789                                   ini->vlan_id, lnk->gid, &lnk->sgid_index,
 790                                   lgr->smc_version == SMC_V2 ?
 791                                                   &ini->smcrv2 : NULL);
 792         if (rc)
 793                 goto out;
 794         rc = smc_llc_link_init(lnk);
 795         if (rc)
 796                 goto out;
 797         rc = smc_wr_alloc_link_mem(lnk);
 798         if (rc)
 799                 goto clear_llc_lnk;
 800         rc = smc_ib_create_protection_domain(lnk);
 801         if (rc)
 802                 goto free_link_mem;
 803         rc = smc_ib_create_queue_pair(lnk);
 804         if (rc)
 805                 goto dealloc_pd;
 806         rc = smc_wr_create_link(lnk);
 807         if (rc)
 808                 goto destroy_qp;
 809         lnk->state = SMC_LNK_ACTIVATING;
 810         return 0;
 811
 812 destroy_qp:
 813         smc_ib_destroy_queue_pair(lnk);
 814 dealloc_pd:
 815         smc_ib_dealloc_protection_domain(lnk);
 816 free_link_mem:
 817         smc_wr_free_link_mem(lnk);
 818 clear_llc_lnk:
 819         smc_llc_link_clear(lnk, false);
 820 out:
 821         smc_ibdev_cnt_dec(lnk);
 822         put_device(&lnk->smcibdev->ibdev->dev);
 823         smcibdev = lnk->smcibdev;
 824         memset(lnk, 0, sizeof(struct smc_link));
 825         lnk->state = SMC_LNK_UNUSED;
 826         if (!atomic_dec_return(&smcibdev->lnk_cnt))
 827                 wake_up(&smcibdev->lnks_deleted);
 828         smc_lgr_put(lgr); /* lgr_hold above */
 829         return rc;
 830 }
 831
 832 /* create a new SMC link group */
 833 static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
 834 {
 835         struct smc_link_group *lgr;
 836         struct list_head *lgr_list;
 837         struct smcd_dev *smcd;
 838         struct smc_link *lnk;
 839         spinlock_t *lgr_lock;
 840         u8 link_idx;
 841         int rc = 0;
 842         int i;
 843
 844         if (ini->is_smcd && ini->vlan_id) {
 845                 if (smc_ism_get_vlan(ini->ism_dev[ini->ism_selected],
 846                                      ini->vlan_id)) {
 847                         rc = SMC_CLC_DECL_ISMVLANERR;
 848                         goto out;
 849                 }
 850         }
 851
 852         lgr = kzalloc(sizeof(*lgr), GFP_KERNEL);
 853         if (!lgr) {
 854                 rc = SMC_CLC_DECL_MEM;
 855                 goto ism_put_vlan;
 856         }
 857         lgr->tx_wq = alloc_workqueue("smc_tx_wq-%*phN", 0, 0,
 858                                      SMC_LGR_ID_SIZE, &lgr->id);
 859         if (!lgr->tx_wq) {
 860                 rc = -ENOMEM;
 861                 goto free_lgr;
 862         }
 863         lgr->is_smcd = ini->is_smcd;
 864         lgr->sync_err = 0;
 865         lgr->terminating = 0;
 866         lgr->freeing = 0;
 867         lgr->vlan_id = ini->vlan_id;
 868         refcount_set(&lgr->refcnt, 1); /* set lgr refcnt to 1 */
 869         init_rwsem(&lgr->sndbufs_lock);
 870         init_rwsem(&lgr->rmbs_lock);
 871         rwlock_init(&lgr->conns_lock);
 872         for (i = 0; i < SMC_RMBE_SIZES; i++) {
 873                 INIT_LIST_HEAD(&lgr->sndbufs[i]);
 874                 INIT_LIST_HEAD(&lgr->rmbs[i]);
 875         }
 876         lgr->next_link_id = 0;
 877         smc_lgr_list.num += SMC_LGR_NUM_INCR;
 878         memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE);
 879         INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
 880         INIT_WORK(&lgr->terminate_work, smc_lgr_terminate_work);
 881         lgr->conns_all = RB_ROOT;
 882         if (ini->is_smcd) {
 883                 /* SMC-D specific settings */
 884                 smcd = ini->ism_dev[ini->ism_selected];
 885                 get_device(smcd->ops->get_dev(smcd));
 886                 lgr->peer_gid.gid =
 887                         ini->ism_peer_gid[ini->ism_selected].gid;
 888                 lgr->peer_gid.gid_ext =
 889                         ini->ism_peer_gid[ini->ism_selected].gid_ext;
 890                 lgr->smcd = ini->ism_dev[ini->ism_selected];
 891                 lgr_list = &ini->ism_dev[ini->ism_selected]->lgr_list;
 892                 lgr_lock = &lgr->smcd->lgr_lock;
 893                 lgr->smc_version = ini->smcd_version;
 894                 lgr->peer_shutdown = 0;
 895                 atomic_inc(&ini->ism_dev[ini->ism_selected]->lgr_cnt);
 896         } else {
 897                 /* SMC-R specific settings */
 898                 struct smc_ib_device *ibdev;
 899                 int ibport;
 900
 901                 lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
 902                 lgr->smc_version = ini->smcr_version;
 903                 memcpy(lgr->peer_systemid, ini->peer_systemid,
 904                        SMC_SYSTEMID_LEN);
 905                 if (lgr->smc_version == SMC_V2) {
 906                         ibdev = ini->smcrv2.ib_dev_v2;
 907                         ibport = ini->smcrv2.ib_port_v2;
 908                         lgr->saddr = ini->smcrv2.saddr;
 909                         lgr->uses_gateway = ini->smcrv2.uses_gateway;
 910                         memcpy(lgr->nexthop_mac, ini->smcrv2.nexthop_mac,
 911                                ETH_ALEN);
 912                         lgr->max_conns = ini->max_conns;
 913                         lgr->max_links = ini->max_links;
 914                 } else {
 915                         ibdev = ini->ib_dev;
 916                         ibport = ini->ib_port;
 917                         lgr->max_conns = SMC_CONN_PER_LGR_MAX;
 918                         lgr->max_links = SMC_LINKS_ADD_LNK_MAX;
 919                 }
 920                 memcpy(lgr->pnet_id, ibdev->pnetid[ibport - 1],
 921                        SMC_MAX_PNETID_LEN);
 922                 rc = smc_wr_alloc_lgr_mem(lgr);
 923                 if (rc)
 924                         goto free_wq;
 925                 smc_llc_lgr_init(lgr, smc);
 926
 927                 link_idx = SMC_SINGLE_LINK;
 928                 lnk = &lgr->lnk[link_idx];
 929                 rc = smcr_link_init(lgr, lnk, link_idx, ini);
 930                 if (rc) {
 931                         smc_wr_free_lgr_mem(lgr);
 932                         goto free_wq;
 933                 }
 934                 lgr->net = smc_ib_net(lnk->smcibdev);
 935                 lgr_list = &smc_lgr_list.list;
 936                 lgr_lock = &smc_lgr_list.lock;
 937                 lgr->buf_type = lgr->net->smc.sysctl_smcr_buf_type;
 938                 atomic_inc(&lgr_cnt);
 939         }
 940         smc->conn.lgr = lgr;
 941         spin_lock_bh(lgr_lock);
 942         list_add_tail(&lgr->list, lgr_list);
 943         spin_unlock_bh(lgr_lock);
 944         return 0;
 945
 946 free_wq:
 947         destroy_workqueue(lgr->tx_wq);
 948 free_lgr:
 949         kfree(lgr);
 950 ism_put_vlan:
 951         if (ini->is_smcd && ini->vlan_id)
 952                 smc_ism_put_vlan(ini->ism_dev[ini->ism_selected], ini->vlan_id);
 953 out:
 954         if (rc < 0) {
 955                 if (rc == -ENOMEM)
 956                         rc = SMC_CLC_DECL_MEM;
 957                 else
 958                         rc = SMC_CLC_DECL_INTERR;
 959         }
 960         return rc;
 961 }
 962
 963 static int smc_write_space(struct smc_connection *conn)
 964 {
 965         int buffer_len = conn->peer_rmbe_size;
 966         union smc_host_cursor prod;
 967         union smc_host_cursor cons;
 968         int space;
 969
 970         smc_curs_copy(&prod, &conn->local_tx_ctrl.prod, conn);
 971         smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
 972         /* determine rx_buf space */
 973         space = buffer_len - smc_curs_diff(buffer_len, &cons, &prod);
 974         return space;
 975 }
 976
 977 static int smc_switch_cursor(struct smc_sock *smc, struct smc_cdc_tx_pend *pend,
 978                              struct smc_wr_buf *wr_buf)
 979 {
 980         struct smc_connection *conn = &smc->conn;
 981         union smc_host_cursor cons, fin;
 982         int rc = 0;
 983         int diff;
 984
 985         smc_curs_copy(&conn->tx_curs_sent, &conn->tx_curs_fin, conn);
 986         smc_curs_copy(&fin, &conn->local_tx_ctrl_fin, conn);
 987         /* set prod cursor to old state, enforce tx_rdma_writes() */
 988         smc_curs_copy(&conn->local_tx_ctrl.prod, &fin, conn);
 989         smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
 990
 991         if (smc_curs_comp(conn->peer_rmbe_size, &cons, &fin) < 0) {
 992                 /* cons cursor advanced more than fin, and prod was set
 993                  * fin above, so now prod is smaller than cons. Fix that.
 994                  */
 995                 diff = smc_curs_diff(conn->peer_rmbe_size, &fin, &cons);
 996                 smc_curs_add(conn->sndbuf_desc->len,
 997                              &conn->tx_curs_sent, diff);
 998                 smc_curs_add(conn->sndbuf_desc->len,
 999                              &conn->tx_curs_fin, diff);
1000
1001                 smp_mb__before_atomic();
1002                 atomic_add(diff, &conn->sndbuf_space);
1003                 smp_mb__after_atomic();
1004
1005                 smc_curs_add(conn->peer_rmbe_size,
1006                              &conn->local_tx_ctrl.prod, diff);
1007                 smc_curs_add(conn->peer_rmbe_size,
1008                              &conn->local_tx_ctrl_fin, diff);
1009         }
1010         /* recalculate, value is used by tx_rdma_writes() */
1011         atomic_set(&smc->conn.peer_rmbe_space, smc_write_space(conn));
1012
1013         if (smc->sk.sk_state != SMC_INIT &&
1014             smc->sk.sk_state != SMC_CLOSED) {
1015                 rc = smcr_cdc_msg_send_validation(conn, pend, wr_buf);
1016                 if (!rc) {
1017                         queue_delayed_work(conn->lgr->tx_wq, &conn->tx_work, 0);
1018                         smc->sk.sk_data_ready(&smc->sk);
1019                 }
1020         } else {
1021                 smc_wr_tx_put_slot(conn->lnk,
1022                                    (struct smc_wr_tx_pend_priv *)pend);
1023         }
1024         return rc;
1025 }
1026
1027 void smc_switch_link_and_count(struct smc_connection *conn,
1028                                struct smc_link *to_lnk)
1029 {
1030         atomic_dec(&conn->lnk->conn_cnt);
1031         /* link_hold in smc_conn_create() */
1032         smcr_link_put(conn->lnk);
1033         conn->lnk = to_lnk;
1034         atomic_inc(&conn->lnk->conn_cnt);
1035         /* link_put in smc_conn_free() */
1036         smcr_link_hold(conn->lnk);
1037 }
1038
1039 struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
1040                                   struct smc_link *from_lnk, bool is_dev_err)
1041 {
1042         struct smc_link *to_lnk = NULL;
1043         struct smc_cdc_tx_pend *pend;
1044         struct smc_connection *conn;
1045         struct smc_wr_buf *wr_buf;
1046         struct smc_sock *smc;
1047         struct rb_node *node;
1048         int i, rc = 0;
1049
1050         /* link is inactive, wake up tx waiters */
1051         smc_wr_wakeup_tx_wait(from_lnk);
1052
1053         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1054                 if (!smc_link_active(&lgr->lnk[i]) || i == from_lnk->link_idx)
1055                         continue;
1056                 if (is_dev_err && from_lnk->smcibdev == lgr->lnk[i].smcibdev &&
1057                     from_lnk->ibport == lgr->lnk[i].ibport) {
1058                         continue;
1059                 }
1060                 to_lnk = &lgr->lnk[i];
1061                 break;
1062         }
1063         if (!to_lnk || !smc_wr_tx_link_hold(to_lnk)) {
1064                 smc_lgr_terminate_sched(lgr);
1065                 return NULL;
1066         }
1067 again:
1068         read_lock_bh(&lgr->conns_lock);
1069         for (node = rb_first(&lgr->conns_all); node; node = rb_next(node)) {
1070                 conn = rb_entry(node, struct smc_connection, alert_node);
1071                 if (conn->lnk != from_lnk)
1072                         continue;
1073                 smc = container_of(conn, struct smc_sock, conn);
1074                 /* conn->lnk not yet set in SMC_INIT state */
1075                 if (smc->sk.sk_state == SMC_INIT)
1076                         continue;
1077                 if (smc->sk.sk_state == SMC_CLOSED ||
1078                     smc->sk.sk_state == SMC_PEERCLOSEWAIT1 ||
1079                     smc->sk.sk_state == SMC_PEERCLOSEWAIT2 ||
1080                     smc->sk.sk_state == SMC_APPFINCLOSEWAIT ||
1081                     smc->sk.sk_state == SMC_APPCLOSEWAIT1 ||
1082                     smc->sk.sk_state == SMC_APPCLOSEWAIT2 ||
1083                     smc->sk.sk_state == SMC_PEERFINCLOSEWAIT ||
1084                     smc->sk.sk_state == SMC_PEERABORTWAIT ||
1085                     smc->sk.sk_state == SMC_PROCESSABORT) {
1086                         spin_lock_bh(&conn->send_lock);
1087                         smc_switch_link_and_count(conn, to_lnk);
1088                         spin_unlock_bh(&conn->send_lock);
1089                         continue;
1090                 }
1091                 sock_hold(&smc->sk);
1092                 read_unlock_bh(&lgr->conns_lock);
1093                 /* pre-fetch buffer outside of send_lock, might sleep */
1094                 rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend);
1095                 if (rc)
1096                         goto err_out;
1097                 /* avoid race with smcr_tx_sndbuf_nonempty() */
1098                 spin_lock_bh(&conn->send_lock);
1099                 smc_switch_link_and_count(conn, to_lnk);
1100                 rc = smc_switch_cursor(smc, pend, wr_buf);
1101                 spin_unlock_bh(&conn->send_lock);
1102                 sock_put(&smc->sk);
1103                 if (rc)
1104                         goto err_out;
1105                 goto again;
1106         }
1107         read_unlock_bh(&lgr->conns_lock);
1108         smc_wr_tx_link_put(to_lnk);
1109         return to_lnk;
1110
1111 err_out:
1112         smcr_link_down_cond_sched(to_lnk);
1113         smc_wr_tx_link_put(to_lnk);
1114         return NULL;
1115 }
1116
1117 static void smcr_buf_unuse(struct smc_buf_desc *buf_desc, bool is_rmb,
1118                            struct smc_link_group *lgr)
1119 {
1120         struct rw_semaphore *lock;      /* lock buffer list */
1121         int rc;
1122
1123         if (is_rmb && buf_desc->is_conf_rkey && !list_empty(&lgr->list)) {
1124                 /* unregister rmb with peer */
1125                 rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
1126                 if (!rc) {
1127                         /* protect against smc_llc_cli_rkey_exchange() */
1128                         down_read(&lgr->llc_conf_mutex);
1129                         smc_llc_do_delete_rkey(lgr, buf_desc);
1130                         buf_desc->is_conf_rkey = false;
1131                         up_read(&lgr->llc_conf_mutex);
1132                         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
1133                 }
1134         }
1135
1136         if (buf_desc->is_reg_err) {
1137                 /* buf registration failed, reuse not possible */
1138                 lock = is_rmb ? &lgr->rmbs_lock :
1139                                 &lgr->sndbufs_lock;
1140                 down_write(lock);
1141                 list_del(&buf_desc->list);
1142                 up_write(lock);
1143
1144                 smc_buf_free(lgr, is_rmb, buf_desc);
1145         } else {
1146                 /* memzero_explicit provides potential memory barrier semantics */
1147                 memzero_explicit(buf_desc->cpu_addr, buf_desc->len);
1148                 WRITE_ONCE(buf_desc->used, 0);
1149         }
1150 }
1151
1152 static void smc_buf_unuse(struct smc_connection *conn,
1153                           struct smc_link_group *lgr)
1154 {
1155         if (conn->sndbuf_desc) {
1156                 if (!lgr->is_smcd && conn->sndbuf_desc->is_vm) {
1157                         smcr_buf_unuse(conn->sndbuf_desc, false, lgr);
1158                 } else {
1159                         memzero_explicit(conn->sndbuf_desc->cpu_addr, conn->sndbuf_desc->len);
1160                         WRITE_ONCE(conn->sndbuf_desc->used, 0);
1161                 }
1162         }
1163         if (conn->rmb_desc) {
1164                 if (!lgr->is_smcd) {
1165                         smcr_buf_unuse(conn->rmb_desc, true, lgr);
1166                 } else {
1167                         memzero_explicit(conn->rmb_desc->cpu_addr,
1168                                          conn->rmb_desc->len + sizeof(struct smcd_cdc_msg));
1169                         WRITE_ONCE(conn->rmb_desc->used, 0);
1170                 }
1171         }
1172 }
1173
1174 /* remove a finished connection from its link group */
1175 void smc_conn_free(struct smc_connection *conn)
1176 {
1177         struct smc_link_group *lgr = conn->lgr;
1178
1179         if (!lgr || conn->freed)
1180                 /* Connection has never been registered in a
1181                  * link group, or has already been freed.
1182                  */
1183                 return;
1184
1185         conn->freed = 1;
1186         if (!smc_conn_lgr_valid(conn))
1187                 /* Connection has already unregistered from
1188                  * link group.
1189                  */
1190                 goto lgr_put;
1191
1192         if (lgr->is_smcd) {
1193                 if (!list_empty(&lgr->list))
1194                         smc_ism_unset_conn(conn);
1195                 tasklet_kill(&conn->rx_tsklet);
1196         } else {
1197                 smc_cdc_wait_pend_tx_wr(conn);
1198                 if (current_work() != &conn->abort_work)
1199                         cancel_work_sync(&conn->abort_work);
1200         }
1201         if (!list_empty(&lgr->list)) {
1202                 smc_buf_unuse(conn, lgr); /* allow buffer reuse */
1203                 smc_lgr_unregister_conn(conn);
1204         }
1205
1206         if (!lgr->conns_num)
1207                 smc_lgr_schedule_free_work(lgr);
1208 lgr_put:
1209         if (!lgr->is_smcd)
1210                 smcr_link_put(conn->lnk); /* link_hold in smc_conn_create() */
1211         smc_lgr_put(lgr); /* lgr_hold in smc_conn_create() */
1212 }
1213
1214 /* unregister a link from a buf_desc */
1215 static void smcr_buf_unmap_link(struct smc_buf_desc *buf_desc, bool is_rmb,
1216                                 struct smc_link *lnk)
1217 {
1218         if (is_rmb || buf_desc->is_vm)
1219                 buf_desc->is_reg_mr[lnk->link_idx] = false;
1220         if (!buf_desc->is_map_ib[lnk->link_idx])
1221                 return;
1222
1223         if ((is_rmb || buf_desc->is_vm) &&
1224             buf_desc->mr[lnk->link_idx]) {
1225                 smc_ib_put_memory_region(buf_desc->mr[lnk->link_idx]);
1226                 buf_desc->mr[lnk->link_idx] = NULL;
1227         }
1228         if (is_rmb)
1229                 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_FROM_DEVICE);
1230         else
1231                 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_TO_DEVICE);
1232
1233         sg_free_table(&buf_desc->sgt[lnk->link_idx]);
1234         buf_desc->is_map_ib[lnk->link_idx] = false;
1235 }
1236
1237 /* unmap all buffers of lgr for a deleted link */
1238 static void smcr_buf_unmap_lgr(struct smc_link *lnk)
1239 {
1240         struct smc_link_group *lgr = lnk->lgr;
1241         struct smc_buf_desc *buf_desc, *bf;
1242         int i;
1243
1244         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1245                 down_write(&lgr->rmbs_lock);
1246                 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list)
1247                         smcr_buf_unmap_link(buf_desc, true, lnk);
1248                 up_write(&lgr->rmbs_lock);
1249
1250                 down_write(&lgr->sndbufs_lock);
1251                 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i],
1252                                          list)
1253                         smcr_buf_unmap_link(buf_desc, false, lnk);
1254                 up_write(&lgr->sndbufs_lock);
1255         }
1256 }
1257
1258 static void smcr_rtoken_clear_link(struct smc_link *lnk)
1259 {
1260         struct smc_link_group *lgr = lnk->lgr;
1261         int i;
1262
1263         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1264                 lgr->rtokens[i][lnk->link_idx].rkey = 0;
1265                 lgr->rtokens[i][lnk->link_idx].dma_addr = 0;
1266         }
1267 }
1268
1269 static void __smcr_link_clear(struct smc_link *lnk)
1270 {
1271         struct smc_link_group *lgr = lnk->lgr;
1272         struct smc_ib_device *smcibdev;
1273
1274         smc_wr_free_link_mem(lnk);
1275         smc_ibdev_cnt_dec(lnk);
1276         put_device(&lnk->smcibdev->ibdev->dev);
1277         smcibdev = lnk->smcibdev;
1278         memset(lnk, 0, sizeof(struct smc_link));
1279         lnk->state = SMC_LNK_UNUSED;
1280         if (!atomic_dec_return(&smcibdev->lnk_cnt))
1281                 wake_up(&smcibdev->lnks_deleted);
1282         smc_lgr_put(lgr); /* lgr_hold in smcr_link_init() */
1283 }
1284
1285 /* must be called under lgr->llc_conf_mutex lock */
1286 void smcr_link_clear(struct smc_link *lnk, bool log)
1287 {
1288         if (!lnk->lgr || lnk->clearing ||
1289             lnk->state == SMC_LNK_UNUSED)
1290                 return;
1291         lnk->clearing = 1;
1292         lnk->peer_qpn = 0;
1293         smc_llc_link_clear(lnk, log);
1294         smcr_buf_unmap_lgr(lnk);
1295         smcr_rtoken_clear_link(lnk);
1296         smc_ib_modify_qp_error(lnk);
1297         smc_wr_free_link(lnk);
1298         smc_ib_destroy_queue_pair(lnk);
1299         smc_ib_dealloc_protection_domain(lnk);
1300         smcr_link_put(lnk); /* theoretically last link_put */
1301 }
1302
1303 void smcr_link_hold(struct smc_link *lnk)
1304 {
1305         refcount_inc(&lnk->refcnt);
1306 }
1307
1308 void smcr_link_put(struct smc_link *lnk)
1309 {
1310         if (refcount_dec_and_test(&lnk->refcnt))
1311                 __smcr_link_clear(lnk);
1312 }
1313
1314 static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb,
1315                           struct smc_buf_desc *buf_desc)
1316 {
1317         int i;
1318
1319         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1320                 smcr_buf_unmap_link(buf_desc, is_rmb, &lgr->lnk[i]);
1321
1322         if (!buf_desc->is_vm && buf_desc->pages)
1323                 __free_pages(buf_desc->pages, buf_desc->order);
1324         else if (buf_desc->is_vm && buf_desc->cpu_addr)
1325                 vfree(buf_desc->cpu_addr);
1326         kfree(buf_desc);
1327 }
1328
1329 static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb,
1330                           struct smc_buf_desc *buf_desc)
1331 {
1332         if (is_dmb) {
1333                 /* restore original buf len */
1334                 buf_desc->len += sizeof(struct smcd_cdc_msg);
1335                 smc_ism_unregister_dmb(lgr->smcd, buf_desc);
1336         } else {
1337                 kfree(buf_desc->cpu_addr);
1338         }
1339         kfree(buf_desc);
1340 }
1341
1342 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
1343                          struct smc_buf_desc *buf_desc)
1344 {
1345         if (lgr->is_smcd)
1346                 smcd_buf_free(lgr, is_rmb, buf_desc);
1347         else
1348                 smcr_buf_free(lgr, is_rmb, buf_desc);
1349 }
1350
1351 static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb)
1352 {
1353         struct smc_buf_desc *buf_desc, *bf_desc;
1354         struct list_head *buf_list;
1355         int i;
1356
1357         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1358                 if (is_rmb)
1359                         buf_list = &lgr->rmbs[i];
1360                 else
1361                         buf_list = &lgr->sndbufs[i];
1362                 list_for_each_entry_safe(buf_desc, bf_desc, buf_list,
1363                                          list) {
1364                         list_del(&buf_desc->list);
1365                         smc_buf_free(lgr, is_rmb, buf_desc);
1366                 }
1367         }
1368 }
1369
1370 static void smc_lgr_free_bufs(struct smc_link_group *lgr)
1371 {
1372         /* free send buffers */
1373         __smc_lgr_free_bufs(lgr, false);
1374         /* free rmbs */
1375         __smc_lgr_free_bufs(lgr, true);
1376 }
1377
1378 /* won't be freed until no one accesses to lgr anymore */
1379 static void __smc_lgr_free(struct smc_link_group *lgr)
1380 {
1381         smc_lgr_free_bufs(lgr);
1382         if (lgr->is_smcd) {
1383                 if (!atomic_dec_return(&lgr->smcd->lgr_cnt))
1384                         wake_up(&lgr->smcd->lgrs_deleted);
1385         } else {
1386                 smc_wr_free_lgr_mem(lgr);
1387                 if (!atomic_dec_return(&lgr_cnt))
1388                         wake_up(&lgrs_deleted);
1389         }
1390         kfree(lgr);
1391 }
1392
1393 /* remove a link group */
1394 static void smc_lgr_free(struct smc_link_group *lgr)
1395 {
1396         int i;
1397
1398         if (!lgr->is_smcd) {
1399                 down_write(&lgr->llc_conf_mutex);
1400                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1401                         if (lgr->lnk[i].state != SMC_LNK_UNUSED)
1402                                 smcr_link_clear(&lgr->lnk[i], false);
1403                 }
1404                 up_write(&lgr->llc_conf_mutex);
1405                 smc_llc_lgr_clear(lgr);
1406         }
1407
1408         destroy_workqueue(lgr->tx_wq);
1409         if (lgr->is_smcd) {
1410                 smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
1411                 put_device(lgr->smcd->ops->get_dev(lgr->smcd));
1412         }
1413         smc_lgr_put(lgr); /* theoretically last lgr_put */
1414 }
1415
1416 void smc_lgr_hold(struct smc_link_group *lgr)
1417 {
1418         refcount_inc(&lgr->refcnt);
1419 }
1420
1421 void smc_lgr_put(struct smc_link_group *lgr)
1422 {
1423         if (refcount_dec_and_test(&lgr->refcnt))
1424                 __smc_lgr_free(lgr);
1425 }
1426
1427 static void smc_sk_wake_ups(struct smc_sock *smc)
1428 {
1429         smc->sk.sk_write_space(&smc->sk);
1430         smc->sk.sk_data_ready(&smc->sk);
1431         smc->sk.sk_state_change(&smc->sk);
1432 }
1433
1434 /* kill a connection */
1435 static void smc_conn_kill(struct smc_connection *conn, bool soft)
1436 {
1437         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1438
1439         if (conn->lgr->is_smcd && conn->lgr->peer_shutdown)
1440                 conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
1441         else
1442                 smc_close_abort(conn);
1443         conn->killed = 1;
1444         smc->sk.sk_err = ECONNABORTED;
1445         smc_sk_wake_ups(smc);
1446         if (conn->lgr->is_smcd) {
1447                 smc_ism_unset_conn(conn);
1448                 if (soft)
1449                         tasklet_kill(&conn->rx_tsklet);
1450                 else
1451                         tasklet_unlock_wait(&conn->rx_tsklet);
1452         } else {
1453                 smc_cdc_wait_pend_tx_wr(conn);
1454         }
1455         smc_lgr_unregister_conn(conn);
1456         smc_close_active_abort(smc);
1457 }
1458
1459 static void smc_lgr_cleanup(struct smc_link_group *lgr)
1460 {
1461         if (lgr->is_smcd) {
1462                 smc_ism_signal_shutdown(lgr);
1463         } else {
1464                 u32 rsn = lgr->llc_termination_rsn;
1465
1466                 if (!rsn)
1467                         rsn = SMC_LLC_DEL_PROG_INIT_TERM;
1468                 smc_llc_send_link_delete_all(lgr, false, rsn);
1469                 smcr_lgr_link_deactivate_all(lgr);
1470         }
1471 }
1472
1473 /* terminate link group
1474  * @soft: true if link group shutdown can take its time
1475  *        false if immediate link group shutdown is required
1476  */
1477 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft)
1478 {
1479         struct smc_connection *conn;
1480         struct smc_sock *smc;
1481         struct rb_node *node;
1482
1483         if (lgr->terminating)
1484                 return; /* lgr already terminating */
1485         /* cancel free_work sync, will terminate when lgr->freeing is set */
1486         cancel_delayed_work(&lgr->free_work);
1487         lgr->terminating = 1;
1488
1489         /* kill remaining link group connections */
1490         read_lock_bh(&lgr->conns_lock);
1491         node = rb_first(&lgr->conns_all);
1492         while (node) {
1493                 read_unlock_bh(&lgr->conns_lock);
1494                 conn = rb_entry(node, struct smc_connection, alert_node);
1495                 smc = container_of(conn, struct smc_sock, conn);
1496                 sock_hold(&smc->sk); /* sock_put below */
1497                 lock_sock(&smc->sk);
1498                 smc_conn_kill(conn, soft);
1499                 release_sock(&smc->sk);
1500                 sock_put(&smc->sk); /* sock_hold above */
1501                 read_lock_bh(&lgr->conns_lock);
1502                 node = rb_first(&lgr->conns_all);
1503         }
1504         read_unlock_bh(&lgr->conns_lock);
1505         smc_lgr_cleanup(lgr);
1506         smc_lgr_free(lgr);
1507 }
1508
1509 /* unlink link group and schedule termination */
1510 void smc_lgr_terminate_sched(struct smc_link_group *lgr)
1511 {
1512         spinlock_t *lgr_lock;
1513
1514         smc_lgr_list_head(lgr, &lgr_lock);
1515         spin_lock_bh(lgr_lock);
1516         if (list_empty(&lgr->list) || lgr->terminating || lgr->freeing) {
1517                 spin_unlock_bh(lgr_lock);
1518                 return; /* lgr already terminating */
1519         }
1520         list_del_init(&lgr->list);
1521         lgr->freeing = 1;
1522         spin_unlock_bh(lgr_lock);
1523         schedule_work(&lgr->terminate_work);
1524 }
1525
1526 /* Called when peer lgr shutdown (regularly or abnormally) is received */
1527 void smc_smcd_terminate(struct smcd_dev *dev, struct smcd_gid *peer_gid,
1528                         unsigned short vlan)
1529 {
1530         struct smc_link_group *lgr, *l;
1531         LIST_HEAD(lgr_free_list);
1532
1533         /* run common cleanup function and build free list */
1534         spin_lock_bh(&dev->lgr_lock);
1535         list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) {
1536                 if ((!peer_gid->gid ||
1537                      (lgr->peer_gid.gid == peer_gid->gid &&
1538                       !smc_ism_is_emulated(dev) ? 1 :
1539                       lgr->peer_gid.gid_ext == peer_gid->gid_ext)) &&
1540                     (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
1541                         if (peer_gid->gid) /* peer triggered termination */
1542                                 lgr->peer_shutdown = 1;
1543                         list_move(&lgr->list, &lgr_free_list);
1544                         lgr->freeing = 1;
1545                 }
1546         }
1547         spin_unlock_bh(&dev->lgr_lock);
1548
1549         /* cancel the regular free workers and actually free lgrs */
1550         list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
1551                 list_del_init(&lgr->list);
1552                 schedule_work(&lgr->terminate_work);
1553         }
1554 }
1555
1556 /* Called when an SMCD device is removed or the smc module is unloaded */
1557 void smc_smcd_terminate_all(struct smcd_dev *smcd)
1558 {
1559         struct smc_link_group *lgr, *lg;
1560         LIST_HEAD(lgr_free_list);
1561
1562         spin_lock_bh(&smcd->lgr_lock);
1563         list_splice_init(&smcd->lgr_list, &lgr_free_list);
1564         list_for_each_entry(lgr, &lgr_free_list, list)
1565                 lgr->freeing = 1;
1566         spin_unlock_bh(&smcd->lgr_lock);
1567
1568         list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1569                 list_del_init(&lgr->list);
1570                 __smc_lgr_terminate(lgr, false);
1571         }
1572
1573         if (atomic_read(&smcd->lgr_cnt))
1574                 wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt));
1575 }
1576
1577 /* Called when an SMCR device is removed or the smc module is unloaded.
1578  * If smcibdev is given, all SMCR link groups using this device are terminated.
1579  * If smcibdev is NULL, all SMCR link groups are terminated.
1580  */
1581 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
1582 {
1583         struct smc_link_group *lgr, *lg;
1584         LIST_HEAD(lgr_free_list);
1585         int i;
1586
1587         spin_lock_bh(&smc_lgr_list.lock);
1588         if (!smcibdev) {
1589                 list_splice_init(&smc_lgr_list.list, &lgr_free_list);
1590                 list_for_each_entry(lgr, &lgr_free_list, list)
1591                         lgr->freeing = 1;
1592         } else {
1593                 list_for_each_entry_safe(lgr, lg, &smc_lgr_list.list, list) {
1594                         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1595                                 if (lgr->lnk[i].smcibdev == smcibdev)
1596                                         smcr_link_down_cond_sched(&lgr->lnk[i]);
1597                         }
1598                 }
1599         }
1600         spin_unlock_bh(&smc_lgr_list.lock);
1601
1602         list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1603                 list_del_init(&lgr->list);
1604                 smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_OP_INIT_TERM);
1605                 __smc_lgr_terminate(lgr, false);
1606         }
1607
1608         if (smcibdev) {
1609                 if (atomic_read(&smcibdev->lnk_cnt))
1610                         wait_event(smcibdev->lnks_deleted,
1611                                    !atomic_read(&smcibdev->lnk_cnt));
1612         } else {
1613                 if (atomic_read(&lgr_cnt))
1614                         wait_event(lgrs_deleted, !atomic_read(&lgr_cnt));
1615         }
1616 }
1617
1618 /* set new lgr type and clear all asymmetric link tagging */
1619 void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type)
1620 {
1621         char *lgr_type = "";
1622         int i;
1623
1624         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1625                 if (smc_link_usable(&lgr->lnk[i]))
1626                         lgr->lnk[i].link_is_asym = false;
1627         if (lgr->type == new_type)
1628                 return;
1629         lgr->type = new_type;
1630
1631         switch (lgr->type) {
1632         case SMC_LGR_NONE:
1633                 lgr_type = "NONE";
1634                 break;
1635         case SMC_LGR_SINGLE:
1636                 lgr_type = "SINGLE";
1637                 break;
1638         case SMC_LGR_SYMMETRIC:
1639                 lgr_type = "SYMMETRIC";
1640                 break;
1641         case SMC_LGR_ASYMMETRIC_PEER:
1642                 lgr_type = "ASYMMETRIC_PEER";
1643                 break;
1644         case SMC_LGR_ASYMMETRIC_LOCAL:
1645                 lgr_type = "ASYMMETRIC_LOCAL";
1646                 break;
1647         }
1648         pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu state changed: "
1649                             "%s, pnetid %.16s\n", SMC_LGR_ID_SIZE, &lgr->id,
1650                             lgr->net->net_cookie, lgr_type, lgr->pnet_id);
1651 }
1652
1653 /* set new lgr type and tag a link as asymmetric */
1654 void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
1655                             enum smc_lgr_type new_type, int asym_lnk_idx)
1656 {
1657         smcr_lgr_set_type(lgr, new_type);
1658         lgr->lnk[asym_lnk_idx].link_is_asym = true;
1659 }
1660
1661 /* abort connection, abort_work scheduled from tasklet context */
1662 static void smc_conn_abort_work(struct work_struct *work)
1663 {
1664         struct smc_connection *conn = container_of(work,
1665                                                    struct smc_connection,
1666                                                    abort_work);
1667         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1668
1669         lock_sock(&smc->sk);
1670         smc_conn_kill(conn, true);
1671         release_sock(&smc->sk);
1672         sock_put(&smc->sk); /* sock_hold done by schedulers of abort_work */
1673 }
1674
1675 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport)
1676 {
1677         struct smc_link_group *lgr, *n;
1678
1679         spin_lock_bh(&smc_lgr_list.lock);
1680         list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1681                 struct smc_link *link;
1682
1683                 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1684                             SMC_MAX_PNETID_LEN) ||
1685                     lgr->type == SMC_LGR_SYMMETRIC ||
1686                     lgr->type == SMC_LGR_ASYMMETRIC_PEER ||
1687                     !rdma_dev_access_netns(smcibdev->ibdev, lgr->net))
1688                         continue;
1689
1690                 if (lgr->type == SMC_LGR_SINGLE && lgr->max_links <= 1)
1691                         continue;
1692
1693                 /* trigger local add link processing */
1694                 link = smc_llc_usable_link(lgr);
1695                 if (link)
1696                         smc_llc_add_link_local(link);
1697         }
1698         spin_unlock_bh(&smc_lgr_list.lock);
1699 }
1700
1701 /* link is down - switch connections to alternate link,
1702  * must be called under lgr->llc_conf_mutex lock
1703  */
1704 static void smcr_link_down(struct smc_link *lnk)
1705 {
1706         struct smc_link_group *lgr = lnk->lgr;
1707         struct smc_link *to_lnk;
1708         int del_link_id;
1709
1710         if (!lgr || lnk->state == SMC_LNK_UNUSED || list_empty(&lgr->list))
1711                 return;
1712
1713         to_lnk = smc_switch_conns(lgr, lnk, true);
1714         if (!to_lnk) { /* no backup link available */
1715                 smcr_link_clear(lnk, true);
1716                 return;
1717         }
1718         smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
1719         del_link_id = lnk->link_id;
1720
1721         if (lgr->role == SMC_SERV) {
1722                 /* trigger local delete link processing */
1723                 smc_llc_srv_delete_link_local(to_lnk, del_link_id);
1724         } else {
1725                 if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
1726                         /* another llc task is ongoing */
1727                         up_write(&lgr->llc_conf_mutex);
1728                         wait_event_timeout(lgr->llc_flow_waiter,
1729                                 (list_empty(&lgr->list) ||
1730                                  lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE),
1731                                 SMC_LLC_WAIT_TIME);
1732                         down_write(&lgr->llc_conf_mutex);
1733                 }
1734                 if (!list_empty(&lgr->list)) {
1735                         smc_llc_send_delete_link(to_lnk, del_link_id,
1736                                                  SMC_LLC_REQ, true,
1737                                                  SMC_LLC_DEL_LOST_PATH);
1738                         smcr_link_clear(lnk, true);
1739                 }
1740                 wake_up(&lgr->llc_flow_waiter); /* wake up next waiter */
1741         }
1742 }
1743
1744 /* must be called under lgr->llc_conf_mutex lock */
1745 void smcr_link_down_cond(struct smc_link *lnk)
1746 {
1747         if (smc_link_downing(&lnk->state)) {
1748                 trace_smcr_link_down(lnk, __builtin_return_address(0));
1749                 smcr_link_down(lnk);
1750         }
1751 }
1752
1753 /* will get the lgr->llc_conf_mutex lock */
1754 void smcr_link_down_cond_sched(struct smc_link *lnk)
1755 {
1756         if (smc_link_downing(&lnk->state)) {
1757                 trace_smcr_link_down(lnk, __builtin_return_address(0));
1758                 schedule_work(&lnk->link_down_wrk);
1759         }
1760 }
1761
1762 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport)
1763 {
1764         struct smc_link_group *lgr, *n;
1765         int i;
1766
1767         list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1768                 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1769                             SMC_MAX_PNETID_LEN))
1770                         continue; /* lgr is not affected */
1771                 if (list_empty(&lgr->list))
1772                         continue;
1773                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1774                         struct smc_link *lnk = &lgr->lnk[i];
1775
1776                         if (smc_link_usable(lnk) &&
1777                             lnk->smcibdev == smcibdev && lnk->ibport == ibport)
1778                                 smcr_link_down_cond_sched(lnk);
1779                 }
1780         }
1781 }
1782
1783 static void smc_link_down_work(struct work_struct *work)
1784 {
1785         struct smc_link *link = container_of(work, struct smc_link,
1786                                              link_down_wrk);
1787         struct smc_link_group *lgr = link->lgr;
1788
1789         if (list_empty(&lgr->list))
1790                 return;
1791         wake_up_all(&lgr->llc_msg_waiter);
1792         down_write(&lgr->llc_conf_mutex);
1793         smcr_link_down(link);
1794         up_write(&lgr->llc_conf_mutex);
1795 }
1796
1797 static int smc_vlan_by_tcpsk_walk(struct net_device *lower_dev,
1798                                   struct netdev_nested_priv *priv)
1799 {
1800         unsigned short *vlan_id = (unsigned short *)priv->data;
1801
1802         if (is_vlan_dev(lower_dev)) {
1803                 *vlan_id = vlan_dev_vlan_id(lower_dev);
1804                 return 1;
1805         }
1806
1807         return 0;
1808 }
1809
1810 /* Determine vlan of internal TCP socket. */
1811 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
1812 {
1813         struct dst_entry *dst = sk_dst_get(clcsock->sk);
1814         struct netdev_nested_priv priv;
1815         struct net_device *ndev;
1816         int rc = 0;
1817
1818         ini->vlan_id = 0;
1819         if (!dst) {
1820                 rc = -ENOTCONN;
1821                 goto out;
1822         }
1823         if (!dst->dev) {
1824                 rc = -ENODEV;
1825                 goto out_rel;
1826         }
1827
1828         ndev = dst->dev;
1829         if (is_vlan_dev(ndev)) {
1830                 ini->vlan_id = vlan_dev_vlan_id(ndev);
1831                 goto out_rel;
1832         }
1833
1834         priv.data = (void *)&ini->vlan_id;
1835         rtnl_lock();
1836         netdev_walk_all_lower_dev(ndev, smc_vlan_by_tcpsk_walk, &priv);
1837         rtnl_unlock();
1838
1839 out_rel:
1840         dst_release(dst);
1841 out:
1842         return rc;
1843 }
1844
1845 static bool smcr_lgr_match(struct smc_link_group *lgr, u8 smcr_version,
1846                            u8 peer_systemid[],
1847                            u8 peer_gid[],
1848                            u8 peer_mac_v1[],
1849                            enum smc_lgr_role role, u32 clcqpn,
1850                            struct net *net)
1851 {
1852         struct smc_link *lnk;
1853         int i;
1854
1855         if (memcmp(lgr->peer_systemid, peer_systemid, SMC_SYSTEMID_LEN) ||
1856             lgr->role != role)
1857                 return false;
1858
1859         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1860                 lnk = &lgr->lnk[i];
1861
1862                 if (!smc_link_active(lnk))
1863                         continue;
1864                 /* use verbs API to check netns, instead of lgr->net */
1865                 if (!rdma_dev_access_netns(lnk->smcibdev->ibdev, net))
1866                         return false;
1867                 if ((lgr->role == SMC_SERV || lnk->peer_qpn == clcqpn) &&
1868                     !memcmp(lnk->peer_gid, peer_gid, SMC_GID_SIZE) &&
1869                     (smcr_version == SMC_V2 ||
1870                      !memcmp(lnk->peer_mac, peer_mac_v1, ETH_ALEN)))
1871                         return true;
1872         }
1873         return false;
1874 }
1875
1876 static bool smcd_lgr_match(struct smc_link_group *lgr,
1877                            struct smcd_dev *smcismdev,
1878                            struct smcd_gid *peer_gid)
1879 {
1880         if (lgr->peer_gid.gid != peer_gid->gid ||
1881             lgr->smcd != smcismdev)
1882                 return false;
1883
1884         if (smc_ism_is_emulated(smcismdev) &&
1885             lgr->peer_gid.gid_ext != peer_gid->gid_ext)
1886                 return false;
1887
1888         return true;
1889 }
1890
1891 /* create a new SMC connection (and a new link group if necessary) */
1892 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
1893 {
1894         struct smc_connection *conn = &smc->conn;
1895         struct net *net = sock_net(&smc->sk);
1896         struct list_head *lgr_list;
1897         struct smc_link_group *lgr;
1898         enum smc_lgr_role role;
1899         spinlock_t *lgr_lock;
1900         int rc = 0;
1901
1902         lgr_list = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_list :
1903                                   &smc_lgr_list.list;
1904         lgr_lock = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_lock :
1905                                   &smc_lgr_list.lock;
1906         ini->first_contact_local = 1;
1907         role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
1908         if (role == SMC_CLNT && ini->first_contact_peer)
1909                 /* create new link group as well */
1910                 goto create;
1911
1912         /* determine if an existing link group can be reused */
1913         spin_lock_bh(lgr_lock);
1914         list_for_each_entry(lgr, lgr_list, list) {
1915                 write_lock_bh(&lgr->conns_lock);
1916                 if ((ini->is_smcd ?
1917                      smcd_lgr_match(lgr, ini->ism_dev[ini->ism_selected],
1918                                     &ini->ism_peer_gid[ini->ism_selected]) :
1919                      smcr_lgr_match(lgr, ini->smcr_version,
1920                                     ini->peer_systemid,
1921                                     ini->peer_gid, ini->peer_mac, role,
1922                                     ini->ib_clcqpn, net)) &&
1923                     !lgr->sync_err &&
1924                     (ini->smcd_version == SMC_V2 ||
1925                      lgr->vlan_id == ini->vlan_id) &&
1926                     (role == SMC_CLNT || ini->is_smcd ||
1927                     (lgr->conns_num < lgr->max_conns &&
1928                       !bitmap_full(lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX)))) {
1929                         /* link group found */
1930                         ini->first_contact_local = 0;
1931                         conn->lgr = lgr;
1932                         rc = smc_lgr_register_conn(conn, false);
1933                         write_unlock_bh(&lgr->conns_lock);
1934                         if (!rc && delayed_work_pending(&lgr->free_work))
1935                                 cancel_delayed_work(&lgr->free_work);
1936                         break;
1937                 }
1938                 write_unlock_bh(&lgr->conns_lock);
1939         }
1940         spin_unlock_bh(lgr_lock);
1941         if (rc)
1942                 return rc;
1943
1944         if (role == SMC_CLNT && !ini->first_contact_peer &&
1945             ini->first_contact_local) {
1946                 /* Server reuses a link group, but Client wants to start
1947                  * a new one
1948                  * send out_of_sync decline, reason synchr. error
1949                  */
1950                 return SMC_CLC_DECL_SYNCERR;
1951         }
1952
1953 create:
1954         if (ini->first_contact_local) {
1955                 rc = smc_lgr_create(smc, ini);
1956                 if (rc)
1957                         goto out;
1958                 lgr = conn->lgr;
1959                 write_lock_bh(&lgr->conns_lock);
1960                 rc = smc_lgr_register_conn(conn, true);
1961                 write_unlock_bh(&lgr->conns_lock);
1962                 if (rc) {
1963                         smc_lgr_cleanup_early(lgr);
1964                         goto out;
1965                 }
1966         }
1967         smc_lgr_hold(conn->lgr); /* lgr_put in smc_conn_free() */
1968         if (!conn->lgr->is_smcd)
1969                 smcr_link_hold(conn->lnk); /* link_put in smc_conn_free() */
1970         conn->freed = 0;
1971         conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
1972         conn->local_tx_ctrl.len = SMC_WR_TX_SIZE;
1973         conn->urg_state = SMC_URG_READ;
1974         init_waitqueue_head(&conn->cdc_pend_tx_wq);
1975         INIT_WORK(&smc->conn.abort_work, smc_conn_abort_work);
1976         if (ini->is_smcd) {
1977                 conn->rx_off = sizeof(struct smcd_cdc_msg);
1978                 smcd_cdc_rx_init(conn); /* init tasklet for this conn */
1979         } else {
1980                 conn->rx_off = 0;
1981         }
1982 #ifndef KERNEL_HAS_ATOMIC64
1983         spin_lock_init(&conn->acurs_lock);
1984 #endif
1985
1986 out:
1987         return rc;
1988 }
1989
1990 #define SMCD_DMBE_SIZES         6 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */
1991 #define SMCR_RMBE_SIZES         5 /* 0 -> 16KB, 1 -> 32KB, .. 5 -> 512KB */
1992
1993 /* convert the RMB size into the compressed notation (minimum 16K, see
1994  * SMCD/R_DMBE_SIZES.
1995  * In contrast to plain ilog2, this rounds towards the next power of 2,
1996  * so the socket application gets at least its desired sndbuf / rcvbuf size.
1997  */
1998 static u8 smc_compress_bufsize(int size, bool is_smcd, bool is_rmb)
1999 {
2000         const unsigned int max_scat = SG_MAX_SINGLE_ALLOC * PAGE_SIZE;
2001         u8 compressed;
2002
2003         if (size <= SMC_BUF_MIN_SIZE)
2004                 return 0;
2005
2006         size = (size - 1) >> 14;  /* convert to 16K multiple */
2007         compressed = min_t(u8, ilog2(size) + 1,
2008                            is_smcd ? SMCD_DMBE_SIZES : SMCR_RMBE_SIZES);
2009
2010         if (!is_smcd && is_rmb)
2011                 /* RMBs are backed by & limited to max size of scatterlists */
2012                 compressed = min_t(u8, compressed, ilog2(max_scat >> 14));
2013
2014         return compressed;
2015 }
2016
2017 /* convert the RMB size from compressed notation into integer */
2018 int smc_uncompress_bufsize(u8 compressed)
2019 {
2020         u32 size;
2021
2022         size = 0x00000001 << (((int)compressed) + 14);
2023         return (int)size;
2024 }
2025
2026 /* try to reuse a sndbuf or rmb description slot for a certain
2027  * buffer size; if not available, return NULL
2028  */
2029 static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize,
2030                                              struct rw_semaphore *lock,
2031                                              struct list_head *buf_list)
2032 {
2033         struct smc_buf_desc *buf_slot;
2034
2035         down_read(lock);
2036         list_for_each_entry(buf_slot, buf_list, list) {
2037                 if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
2038                         up_read(lock);
2039                         return buf_slot;
2040                 }
2041         }
2042         up_read(lock);
2043         return NULL;
2044 }
2045
2046 /* one of the conditions for announcing a receiver's current window size is
2047  * that it "results in a minimum increase in the window size of 10% of the
2048  * receive buffer space" [RFC7609]
2049  */
2050 static inline int smc_rmb_wnd_update_limit(int rmbe_size)
2051 {
2052         return max_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
2053 }
2054
2055 /* map an buf to a link */
2056 static int smcr_buf_map_link(struct smc_buf_desc *buf_desc, bool is_rmb,
2057                              struct smc_link *lnk)
2058 {
2059         int rc, i, nents, offset, buf_size, size, access_flags;
2060         struct scatterlist *sg;
2061         void *buf;
2062
2063         if (buf_desc->is_map_ib[lnk->link_idx])
2064                 return 0;
2065
2066         if (buf_desc->is_vm) {
2067                 buf = buf_desc->cpu_addr;
2068                 buf_size = buf_desc->len;
2069                 offset = offset_in_page(buf_desc->cpu_addr);
2070                 nents = PAGE_ALIGN(buf_size + offset) / PAGE_SIZE;
2071         } else {
2072                 nents = 1;
2073         }
2074
2075         rc = sg_alloc_table(&buf_desc->sgt[lnk->link_idx], nents, GFP_KERNEL);
2076         if (rc)
2077                 return rc;
2078
2079         if (buf_desc->is_vm) {
2080                 /* virtually contiguous buffer */
2081                 for_each_sg(buf_desc->sgt[lnk->link_idx].sgl, sg, nents, i) {
2082                         size = min_t(int, PAGE_SIZE - offset, buf_size);
2083                         sg_set_page(sg, vmalloc_to_page(buf), size, offset);
2084                         buf += size / sizeof(*buf);
2085                         buf_size -= size;
2086                         offset = 0;
2087                 }
2088         } else {
2089                 /* physically contiguous buffer */
2090                 sg_set_buf(buf_desc->sgt[lnk->link_idx].sgl,
2091                            buf_desc->cpu_addr, buf_desc->len);
2092         }
2093
2094         /* map sg table to DMA address */
2095         rc = smc_ib_buf_map_sg(lnk, buf_desc,
2096                                is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2097         /* SMC protocol depends on mapping to one DMA address only */
2098         if (rc != nents) {
2099                 rc = -EAGAIN;
2100                 goto free_table;
2101         }
2102
2103         buf_desc->is_dma_need_sync |=
2104                 smc_ib_is_sg_need_sync(lnk, buf_desc) << lnk->link_idx;
2105
2106         if (is_rmb || buf_desc->is_vm) {
2107                 /* create a new memory region for the RMB or vzalloced sndbuf */
2108                 access_flags = is_rmb ?
2109                                IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
2110                                IB_ACCESS_LOCAL_WRITE;
2111
2112                 rc = smc_ib_get_memory_region(lnk->roce_pd, access_flags,
2113                                               buf_desc, lnk->link_idx);
2114                 if (rc)
2115                         goto buf_unmap;
2116                 smc_ib_sync_sg_for_device(lnk, buf_desc,
2117                                           is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2118         }
2119         buf_desc->is_map_ib[lnk->link_idx] = true;
2120         return 0;
2121
2122 buf_unmap:
2123         smc_ib_buf_unmap_sg(lnk, buf_desc,
2124                             is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2125 free_table:
2126         sg_free_table(&buf_desc->sgt[lnk->link_idx]);
2127         return rc;
2128 }
2129
2130 /* register a new buf on IB device, rmb or vzalloced sndbuf
2131  * must be called under lgr->llc_conf_mutex lock
2132  */
2133 int smcr_link_reg_buf(struct smc_link *link, struct smc_buf_desc *buf_desc)
2134 {
2135         if (list_empty(&link->lgr->list))
2136                 return -ENOLINK;
2137         if (!buf_desc->is_reg_mr[link->link_idx]) {
2138                 /* register memory region for new buf */
2139                 if (buf_desc->is_vm)
2140                         buf_desc->mr[link->link_idx]->iova =
2141                                 (uintptr_t)buf_desc->cpu_addr;
2142                 if (smc_wr_reg_send(link, buf_desc->mr[link->link_idx])) {
2143                         buf_desc->is_reg_err = true;
2144                         return -EFAULT;
2145                 }
2146                 buf_desc->is_reg_mr[link->link_idx] = true;
2147         }
2148         return 0;
2149 }
2150
2151 static int _smcr_buf_map_lgr(struct smc_link *lnk, struct rw_semaphore *lock,
2152                              struct list_head *lst, bool is_rmb)
2153 {
2154         struct smc_buf_desc *buf_desc, *bf;
2155         int rc = 0;
2156
2157         down_write(lock);
2158         list_for_each_entry_safe(buf_desc, bf, lst, list) {
2159                 if (!buf_desc->used)
2160                         continue;
2161                 rc = smcr_buf_map_link(buf_desc, is_rmb, lnk);
2162                 if (rc)
2163                         goto out;
2164         }
2165 out:
2166         up_write(lock);
2167         return rc;
2168 }
2169
2170 /* map all used buffers of lgr for a new link */
2171 int smcr_buf_map_lgr(struct smc_link *lnk)
2172 {
2173         struct smc_link_group *lgr = lnk->lgr;
2174         int i, rc = 0;
2175
2176         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2177                 rc = _smcr_buf_map_lgr(lnk, &lgr->rmbs_lock,
2178                                        &lgr->rmbs[i], true);
2179                 if (rc)
2180                         return rc;
2181                 rc = _smcr_buf_map_lgr(lnk, &lgr->sndbufs_lock,
2182                                        &lgr->sndbufs[i], false);
2183                 if (rc)
2184                         return rc;
2185         }
2186         return 0;
2187 }
2188
2189 /* register all used buffers of lgr for a new link,
2190  * must be called under lgr->llc_conf_mutex lock
2191  */
2192 int smcr_buf_reg_lgr(struct smc_link *lnk)
2193 {
2194         struct smc_link_group *lgr = lnk->lgr;
2195         struct smc_buf_desc *buf_desc, *bf;
2196         int i, rc = 0;
2197
2198         /* reg all RMBs for a new link */
2199         down_write(&lgr->rmbs_lock);
2200         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2201                 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list) {
2202                         if (!buf_desc->used)
2203                                 continue;
2204                         rc = smcr_link_reg_buf(lnk, buf_desc);
2205                         if (rc) {
2206                                 up_write(&lgr->rmbs_lock);
2207                                 return rc;
2208                         }
2209                 }
2210         }
2211         up_write(&lgr->rmbs_lock);
2212
2213         if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
2214                 return rc;
2215
2216         /* reg all vzalloced sndbufs for a new link */
2217         down_write(&lgr->sndbufs_lock);
2218         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2219                 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i], list) {
2220                         if (!buf_desc->used || !buf_desc->is_vm)
2221                                 continue;
2222                         rc = smcr_link_reg_buf(lnk, buf_desc);
2223                         if (rc) {
2224                                 up_write(&lgr->sndbufs_lock);
2225                                 return rc;
2226                         }
2227                 }
2228         }
2229         up_write(&lgr->sndbufs_lock);
2230         return rc;
2231 }
2232
2233 static struct smc_buf_desc *smcr_new_buf_create(struct smc_link_group *lgr,
2234                                                 bool is_rmb, int bufsize)
2235 {
2236         struct smc_buf_desc *buf_desc;
2237
2238         /* try to alloc a new buffer */
2239         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
2240         if (!buf_desc)
2241                 return ERR_PTR(-ENOMEM);
2242
2243         switch (lgr->buf_type) {
2244         case SMCR_PHYS_CONT_BUFS:
2245         case SMCR_MIXED_BUFS:
2246                 buf_desc->order = get_order(bufsize);
2247                 buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN |
2248                                               __GFP_NOMEMALLOC | __GFP_COMP |
2249                                               __GFP_NORETRY | __GFP_ZERO,
2250                                               buf_desc->order);
2251                 if (buf_desc->pages) {
2252                         buf_desc->cpu_addr =
2253                                 (void *)page_address(buf_desc->pages);
2254                         buf_desc->len = bufsize;
2255                         buf_desc->is_vm = false;
2256                         break;
2257                 }
2258                 if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
2259                         goto out;
2260                 fallthrough;    // try virtually continguous buf
2261         case SMCR_VIRT_CONT_BUFS:
2262                 buf_desc->order = get_order(bufsize);
2263                 buf_desc->cpu_addr = vzalloc(PAGE_SIZE << buf_desc->order);
2264                 if (!buf_desc->cpu_addr)
2265                         goto out;
2266                 buf_desc->pages = NULL;
2267                 buf_desc->len = bufsize;
2268                 buf_desc->is_vm = true;
2269                 break;
2270         }
2271         return buf_desc;
2272
2273 out:
2274         kfree(buf_desc);
2275         return ERR_PTR(-EAGAIN);
2276 }
2277
2278 /* map buf_desc on all usable links,
2279  * unused buffers stay mapped as long as the link is up
2280  */
2281 static int smcr_buf_map_usable_links(struct smc_link_group *lgr,
2282                                      struct smc_buf_desc *buf_desc, bool is_rmb)
2283 {
2284         int i, rc = 0, cnt = 0;
2285
2286         /* protect against parallel link reconfiguration */
2287         down_read(&lgr->llc_conf_mutex);
2288         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2289                 struct smc_link *lnk = &lgr->lnk[i];
2290
2291                 if (!smc_link_usable(lnk))
2292                         continue;
2293                 if (smcr_buf_map_link(buf_desc, is_rmb, lnk)) {
2294                         rc = -ENOMEM;
2295                         goto out;
2296                 }
2297                 cnt++;
2298         }
2299 out:
2300         up_read(&lgr->llc_conf_mutex);
2301         if (!rc && !cnt)
2302                 rc = -EINVAL;
2303         return rc;
2304 }
2305
2306 static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr,
2307                                                 bool is_dmb, int bufsize)
2308 {
2309         struct smc_buf_desc *buf_desc;
2310         int rc;
2311
2312         /* try to alloc a new DMB */
2313         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
2314         if (!buf_desc)
2315                 return ERR_PTR(-ENOMEM);
2316         if (is_dmb) {
2317                 rc = smc_ism_register_dmb(lgr, bufsize, buf_desc);
2318                 if (rc) {
2319                         kfree(buf_desc);
2320                         if (rc == -ENOMEM)
2321                                 return ERR_PTR(-EAGAIN);
2322                         if (rc == -ENOSPC)
2323                                 return ERR_PTR(-ENOSPC);
2324                         return ERR_PTR(-EIO);
2325                 }
2326                 buf_desc->pages = virt_to_page(buf_desc->cpu_addr);
2327                 /* CDC header stored in buf. So, pretend it was smaller */
2328                 buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg);
2329         } else {
2330                 buf_desc->cpu_addr = kzalloc(bufsize, GFP_KERNEL |
2331                                              __GFP_NOWARN | __GFP_NORETRY |
2332                                              __GFP_NOMEMALLOC);
2333                 if (!buf_desc->cpu_addr) {
2334                         kfree(buf_desc);
2335                         return ERR_PTR(-EAGAIN);
2336                 }
2337                 buf_desc->len = bufsize;
2338         }
2339         return buf_desc;
2340 }
2341
2342 static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb)
2343 {
2344         struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM);
2345         struct smc_connection *conn = &smc->conn;
2346         struct smc_link_group *lgr = conn->lgr;
2347         struct list_head *buf_list;
2348         int bufsize, bufsize_comp;
2349         struct rw_semaphore *lock;      /* lock buffer list */
2350         bool is_dgraded = false;
2351
2352         if (is_rmb)
2353                 /* use socket recv buffer size (w/o overhead) as start value */
2354                 bufsize = smc->sk.sk_rcvbuf / 2;
2355         else
2356                 /* use socket send buffer size (w/o overhead) as start value */
2357                 bufsize = smc->sk.sk_sndbuf / 2;
2358
2359         for (bufsize_comp = smc_compress_bufsize(bufsize, is_smcd, is_rmb);
2360              bufsize_comp >= 0; bufsize_comp--) {
2361                 if (is_rmb) {
2362                         lock = &lgr->rmbs_lock;
2363                         buf_list = &lgr->rmbs[bufsize_comp];
2364                 } else {
2365                         lock = &lgr->sndbufs_lock;
2366                         buf_list = &lgr->sndbufs[bufsize_comp];
2367                 }
2368                 bufsize = smc_uncompress_bufsize(bufsize_comp);
2369
2370                 /* check for reusable slot in the link group */
2371                 buf_desc = smc_buf_get_slot(bufsize_comp, lock, buf_list);
2372                 if (buf_desc) {
2373                         buf_desc->is_dma_need_sync = 0;
2374                         SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
2375                         SMC_STAT_BUF_REUSE(smc, is_smcd, is_rmb);
2376                         break; /* found reusable slot */
2377                 }
2378
2379                 if (is_smcd)
2380                         buf_desc = smcd_new_buf_create(lgr, is_rmb, bufsize);
2381                 else
2382                         buf_desc = smcr_new_buf_create(lgr, is_rmb, bufsize);
2383
2384                 if (PTR_ERR(buf_desc) == -ENOMEM)
2385                         break;
2386                 if (IS_ERR(buf_desc)) {
2387                         if (!is_dgraded) {
2388                                 is_dgraded = true;
2389                                 SMC_STAT_RMB_DOWNGRADED(smc, is_smcd, is_rmb);
2390                         }
2391                         continue;
2392                 }
2393
2394                 SMC_STAT_RMB_ALLOC(smc, is_smcd, is_rmb);
2395                 SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
2396                 buf_desc->used = 1;
2397                 down_write(lock);
2398                 list_add(&buf_desc->list, buf_list);
2399                 up_write(lock);
2400                 break; /* found */
2401         }
2402
2403         if (IS_ERR(buf_desc))
2404                 return PTR_ERR(buf_desc);
2405
2406         if (!is_smcd) {
2407                 if (smcr_buf_map_usable_links(lgr, buf_desc, is_rmb)) {
2408                         smcr_buf_unuse(buf_desc, is_rmb, lgr);
2409                         return -ENOMEM;
2410                 }
2411         }
2412
2413         if (is_rmb) {
2414                 conn->rmb_desc = buf_desc;
2415                 conn->rmbe_size_comp = bufsize_comp;
2416                 smc->sk.sk_rcvbuf = bufsize * 2;
2417                 atomic_set(&conn->bytes_to_rcv, 0);
2418                 conn->rmbe_update_limit =
2419                         smc_rmb_wnd_update_limit(buf_desc->len);
2420                 if (is_smcd)
2421                         smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */
2422         } else {
2423                 conn->sndbuf_desc = buf_desc;
2424                 smc->sk.sk_sndbuf = bufsize * 2;
2425                 atomic_set(&conn->sndbuf_space, bufsize);
2426         }
2427         return 0;
2428 }
2429
2430 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
2431 {
2432         if (!conn->sndbuf_desc->is_dma_need_sync)
2433                 return;
2434         if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd ||
2435             !smc_link_active(conn->lnk))
2436                 return;
2437         smc_ib_sync_sg_for_device(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
2438 }
2439
2440 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
2441 {
2442         int i;
2443
2444         if (!conn->rmb_desc->is_dma_need_sync)
2445                 return;
2446         if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd)
2447                 return;
2448         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2449                 if (!smc_link_active(&conn->lgr->lnk[i]))
2450                         continue;
2451                 smc_ib_sync_sg_for_cpu(&conn->lgr->lnk[i], conn->rmb_desc,
2452                                        DMA_FROM_DEVICE);
2453         }
2454 }
2455
2456 /* create the send and receive buffer for an SMC socket;
2457  * receive buffers are called RMBs;
2458  * (even though the SMC protocol allows more than one RMB-element per RMB,
2459  * the Linux implementation uses just one RMB-element per RMB, i.e. uses an
2460  * extra RMB for every connection in a link group
2461  */
2462 int smc_buf_create(struct smc_sock *smc, bool is_smcd)
2463 {
2464         int rc;
2465
2466         /* create send buffer */
2467         rc = __smc_buf_create(smc, is_smcd, false);
2468         if (rc)
2469                 return rc;
2470         /* create rmb */
2471         rc = __smc_buf_create(smc, is_smcd, true);
2472         if (rc) {
2473                 down_write(&smc->conn.lgr->sndbufs_lock);
2474                 list_del(&smc->conn.sndbuf_desc->list);
2475                 up_write(&smc->conn.lgr->sndbufs_lock);
2476                 smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc);
2477                 smc->conn.sndbuf_desc = NULL;
2478         }
2479         return rc;
2480 }
2481
2482 static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
2483 {
2484         int i;
2485
2486         for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) {
2487                 if (!test_and_set_bit(i, lgr->rtokens_used_mask))
2488                         return i;
2489         }
2490         return -ENOSPC;
2491 }
2492
2493 static int smc_rtoken_find_by_link(struct smc_link_group *lgr, int lnk_idx,
2494                                    u32 rkey)
2495 {
2496         int i;
2497
2498         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2499                 if (test_bit(i, lgr->rtokens_used_mask) &&
2500                     lgr->rtokens[i][lnk_idx].rkey == rkey)
2501                         return i;
2502         }
2503         return -ENOENT;
2504 }
2505
2506 /* set rtoken for a new link to an existing rmb */
2507 void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
2508                     __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey)
2509 {
2510         int rtok_idx;
2511
2512         rtok_idx = smc_rtoken_find_by_link(lgr, link_idx, ntohl(nw_rkey_known));
2513         if (rtok_idx == -ENOENT)
2514                 return;
2515         lgr->rtokens[rtok_idx][link_idx_new].rkey = ntohl(nw_rkey);
2516         lgr->rtokens[rtok_idx][link_idx_new].dma_addr = be64_to_cpu(nw_vaddr);
2517 }
2518
2519 /* set rtoken for a new link whose link_id is given */
2520 void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
2521                      __be64 nw_vaddr, __be32 nw_rkey)
2522 {
2523         u64 dma_addr = be64_to_cpu(nw_vaddr);
2524         u32 rkey = ntohl(nw_rkey);
2525         bool found = false;
2526         int link_idx;
2527
2528         for (link_idx = 0; link_idx < SMC_LINKS_PER_LGR_MAX; link_idx++) {
2529                 if (lgr->lnk[link_idx].link_id == link_id) {
2530                         found = true;
2531                         break;
2532                 }
2533         }
2534         if (!found)
2535                 return;
2536         lgr->rtokens[rtok_idx][link_idx].rkey = rkey;
2537         lgr->rtokens[rtok_idx][link_idx].dma_addr = dma_addr;
2538 }
2539
2540 /* add a new rtoken from peer */
2541 int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey)
2542 {
2543         struct smc_link_group *lgr = smc_get_lgr(lnk);
2544         u64 dma_addr = be64_to_cpu(nw_vaddr);
2545         u32 rkey = ntohl(nw_rkey);
2546         int i;
2547
2548         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2549                 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2550                     lgr->rtokens[i][lnk->link_idx].dma_addr == dma_addr &&
2551                     test_bit(i, lgr->rtokens_used_mask)) {
2552                         /* already in list */
2553                         return i;
2554                 }
2555         }
2556         i = smc_rmb_reserve_rtoken_idx(lgr);
2557         if (i < 0)
2558                 return i;
2559         lgr->rtokens[i][lnk->link_idx].rkey = rkey;
2560         lgr->rtokens[i][lnk->link_idx].dma_addr = dma_addr;
2561         return i;
2562 }
2563
2564 /* delete an rtoken from all links */
2565 int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey)
2566 {
2567         struct smc_link_group *lgr = smc_get_lgr(lnk);
2568         u32 rkey = ntohl(nw_rkey);
2569         int i, j;
2570
2571         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2572                 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2573                     test_bit(i, lgr->rtokens_used_mask)) {
2574                         for (j = 0; j < SMC_LINKS_PER_LGR_MAX; j++) {
2575                                 lgr->rtokens[i][j].rkey = 0;
2576                                 lgr->rtokens[i][j].dma_addr = 0;
2577                         }
2578                         clear_bit(i, lgr->rtokens_used_mask);
2579                         return 0;
2580                 }
2581         }
2582         return -ENOENT;
2583 }
2584
2585 /* save rkey and dma_addr received from peer during clc handshake */
2586 int smc_rmb_rtoken_handling(struct smc_connection *conn,
2587                             struct smc_link *lnk,
2588                             struct smc_clc_msg_accept_confirm *clc)
2589 {
2590         conn->rtoken_idx = smc_rtoken_add(lnk, clc->r0.rmb_dma_addr,
2591                                           clc->r0.rmb_rkey);
2592         if (conn->rtoken_idx < 0)
2593                 return conn->rtoken_idx;
2594         return 0;
2595 }
2596
2597 static void smc_core_going_away(void)
2598 {
2599         struct smc_ib_device *smcibdev;
2600         struct smcd_dev *smcd;
2601
2602         mutex_lock(&smc_ib_devices.mutex);
2603         list_for_each_entry(smcibdev, &smc_ib_devices.list, list) {
2604                 int i;
2605
2606                 for (i = 0; i < SMC_MAX_PORTS; i++)
2607                         set_bit(i, smcibdev->ports_going_away);
2608         }
2609         mutex_unlock(&smc_ib_devices.mutex);
2610
2611         mutex_lock(&smcd_dev_list.mutex);
2612         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2613                 smcd->going_away = 1;
2614         }
2615         mutex_unlock(&smcd_dev_list.mutex);
2616 }
2617
2618 /* Clean up all SMC link groups */
2619 static void smc_lgrs_shutdown(void)
2620 {
2621         struct smcd_dev *smcd;
2622
2623         smc_core_going_away();
2624
2625         smc_smcr_terminate_all(NULL);
2626
2627         mutex_lock(&smcd_dev_list.mutex);
2628         list_for_each_entry(smcd, &smcd_dev_list.list, list)
2629                 smc_smcd_terminate_all(smcd);
2630         mutex_unlock(&smcd_dev_list.mutex);
2631 }
2632
2633 static int smc_core_reboot_event(struct notifier_block *this,
2634                                  unsigned long event, void *ptr)
2635 {
2636         smc_lgrs_shutdown();
2637         smc_ib_unregister_client();
2638         smc_ism_exit();
2639         return 0;
2640 }
2641
2642 static struct notifier_block smc_reboot_notifier = {
2643         .notifier_call = smc_core_reboot_event,
2644 };
2645
2646 int __init smc_core_init(void)
2647 {
2648         return register_reboot_notifier(&smc_reboot_notifier);
2649 }
2650
2651 /* Called (from smc_exit) when module is removed */
2652 void smc_core_exit(void)
2653 {
2654         unregister_reboot_notifier(&smc_reboot_notifier);
2655         smc_lgrs_shutdown();
2656 }