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         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 131                 struct smc_link *lnk = &conn->lgr->lnk[i];
 132
 133                 if (lnk->state != expected || lnk->link_is_asym)
 134                         continue;
 135                 if (conn->lgr->role == SMC_CLNT) {
 136                         conn->lnk = lnk; /* temporary, SMC server assigns link*/
 137                         break;
 138                 }
 139                 if (conn->lgr->conns_num % 2) {
 140                         for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) {
 141                                 struct smc_link *lnk2;
 142
 143                                 lnk2 = &conn->lgr->lnk[j];
 144                                 if (lnk2->state == expected &&
 145                                     !lnk2->link_is_asym) {
 146                                         conn->lnk = lnk2;
 147                                         break;
 148                                 }
 149                         }
 150                 }
 151                 if (!conn->lnk)
 152                         conn->lnk = lnk;
 153                 break;
 154         }
 155         if (!conn->lnk)
 156                 return SMC_CLC_DECL_NOACTLINK;
 157         atomic_inc(&conn->lnk->conn_cnt);
 158         return 0;
 159 }
 160
 161 /* Register connection in link group by assigning an alert token
 162  * registered in a search tree.
 163  * Requires @conns_lock
 164  * Note that '0' is a reserved value and not assigned.
 165  */
 166 static int smc_lgr_register_conn(struct smc_connection *conn, bool first)
 167 {
 168         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 169         static atomic_t nexttoken = ATOMIC_INIT(0);
 170         int rc;
 171
 172         if (!conn->lgr->is_smcd) {
 173                 rc = smcr_lgr_conn_assign_link(conn, first);
 174                 if (rc) {
 175                         conn->lgr = NULL;
 176                         return rc;
 177                 }
 178         }
 179         /* find a new alert_token_local value not yet used by some connection
 180          * in this link group
 181          */
 182         sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */
 183         while (!conn->alert_token_local) {
 184                 conn->alert_token_local = atomic_inc_return(&nexttoken);
 185                 if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr))
 186                         conn->alert_token_local = 0;
 187         }
 188         smc_lgr_add_alert_token(conn);
 189         conn->lgr->conns_num++;
 190         return 0;
 191 }
 192
 193 /* Unregister connection and reset the alert token of the given connection<
 194  */
 195 static void __smc_lgr_unregister_conn(struct smc_connection *conn)
 196 {
 197         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 198         struct smc_link_group *lgr = conn->lgr;
 199
 200         rb_erase(&conn->alert_node, &lgr->conns_all);
 201         if (conn->lnk)
 202                 atomic_dec(&conn->lnk->conn_cnt);
 203         lgr->conns_num--;
 204         conn->alert_token_local = 0;
 205         sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
 206 }
 207
 208 /* Unregister connection from lgr
 209  */
 210 static void smc_lgr_unregister_conn(struct smc_connection *conn)
 211 {
 212         struct smc_link_group *lgr = conn->lgr;
 213
 214         if (!smc_conn_lgr_valid(conn))
 215                 return;
 216         write_lock_bh(&lgr->conns_lock);
 217         if (conn->alert_token_local) {
 218                 __smc_lgr_unregister_conn(conn);
 219         }
 220         write_unlock_bh(&lgr->conns_lock);
 221 }
 222
 223 int smc_nl_get_sys_info(struct sk_buff *skb, struct netlink_callback *cb)
 224 {
 225         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 226         char hostname[SMC_MAX_HOSTNAME_LEN + 1];
 227         char smc_seid[SMC_MAX_EID_LEN + 1];
 228         struct nlattr *attrs;
 229         u8 *seid = NULL;
 230         u8 *host = NULL;
 231         void *nlh;
 232
 233         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 234                           &smc_gen_nl_family, NLM_F_MULTI,
 235                           SMC_NETLINK_GET_SYS_INFO);
 236         if (!nlh)
 237                 goto errmsg;
 238         if (cb_ctx->pos[0])
 239                 goto errout;
 240         attrs = nla_nest_start(skb, SMC_GEN_SYS_INFO);
 241         if (!attrs)
 242                 goto errout;
 243         if (nla_put_u8(skb, SMC_NLA_SYS_VER, SMC_V2))
 244                 goto errattr;
 245         if (nla_put_u8(skb, SMC_NLA_SYS_REL, SMC_RELEASE))
 246                 goto errattr;
 247         if (nla_put_u8(skb, SMC_NLA_SYS_IS_ISM_V2, smc_ism_is_v2_capable()))
 248                 goto errattr;
 249         if (nla_put_u8(skb, SMC_NLA_SYS_IS_SMCR_V2, true))
 250                 goto errattr;
 251         smc_clc_get_hostname(&host);
 252         if (host) {
 253                 memcpy(hostname, host, SMC_MAX_HOSTNAME_LEN);
 254                 hostname[SMC_MAX_HOSTNAME_LEN] = 0;
 255                 if (nla_put_string(skb, SMC_NLA_SYS_LOCAL_HOST, hostname))
 256                         goto errattr;
 257         }
 258         if (smc_ism_is_v2_capable()) {
 259                 smc_ism_get_system_eid(&seid);
 260                 memcpy(smc_seid, seid, SMC_MAX_EID_LEN);
 261                 smc_seid[SMC_MAX_EID_LEN] = 0;
 262                 if (nla_put_string(skb, SMC_NLA_SYS_SEID, smc_seid))
 263                         goto errattr;
 264         }
 265         nla_nest_end(skb, attrs);
 266         genlmsg_end(skb, nlh);
 267         cb_ctx->pos[0] = 1;
 268         return skb->len;
 269
 270 errattr:
 271         nla_nest_cancel(skb, attrs);
 272 errout:
 273         genlmsg_cancel(skb, nlh);
 274 errmsg:
 275         return skb->len;
 276 }
 277
 278 /* Fill SMC_NLA_LGR_D_V2_COMMON/SMC_NLA_LGR_R_V2_COMMON nested attributes */
 279 static int smc_nl_fill_lgr_v2_common(struct smc_link_group *lgr,
 280                                      struct sk_buff *skb,
 281                                      struct netlink_callback *cb,
 282                                      struct nlattr *v2_attrs)
 283 {
 284         char smc_host[SMC_MAX_HOSTNAME_LEN + 1];
 285         char smc_eid[SMC_MAX_EID_LEN + 1];
 286
 287         if (nla_put_u8(skb, SMC_NLA_LGR_V2_VER, lgr->smc_version))
 288                 goto errv2attr;
 289         if (nla_put_u8(skb, SMC_NLA_LGR_V2_REL, lgr->peer_smc_release))
 290                 goto errv2attr;
 291         if (nla_put_u8(skb, SMC_NLA_LGR_V2_OS, lgr->peer_os))
 292                 goto errv2attr;
 293         memcpy(smc_host, lgr->peer_hostname, SMC_MAX_HOSTNAME_LEN);
 294         smc_host[SMC_MAX_HOSTNAME_LEN] = 0;
 295         if (nla_put_string(skb, SMC_NLA_LGR_V2_PEER_HOST, smc_host))
 296                 goto errv2attr;
 297         memcpy(smc_eid, lgr->negotiated_eid, SMC_MAX_EID_LEN);
 298         smc_eid[SMC_MAX_EID_LEN] = 0;
 299         if (nla_put_string(skb, SMC_NLA_LGR_V2_NEG_EID, smc_eid))
 300                 goto errv2attr;
 301
 302         nla_nest_end(skb, v2_attrs);
 303         return 0;
 304
 305 errv2attr:
 306         nla_nest_cancel(skb, v2_attrs);
 307         return -EMSGSIZE;
 308 }
 309
 310 static int smc_nl_fill_smcr_lgr_v2(struct smc_link_group *lgr,
 311                                    struct sk_buff *skb,
 312                                    struct netlink_callback *cb)
 313 {
 314         struct nlattr *v2_attrs;
 315
 316         v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2);
 317         if (!v2_attrs)
 318                 goto errattr;
 319         if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_DIRECT, !lgr->uses_gateway))
 320                 goto errv2attr;
 321
 322         nla_nest_end(skb, v2_attrs);
 323         return 0;
 324
 325 errv2attr:
 326         nla_nest_cancel(skb, v2_attrs);
 327 errattr:
 328         return -EMSGSIZE;
 329 }
 330
 331 static int smc_nl_fill_lgr(struct smc_link_group *lgr,
 332                            struct sk_buff *skb,
 333                            struct netlink_callback *cb)
 334 {
 335         char smc_target[SMC_MAX_PNETID_LEN + 1];
 336         struct nlattr *attrs, *v2_attrs;
 337
 338         attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCR);
 339         if (!attrs)
 340                 goto errout;
 341
 342         if (nla_put_u32(skb, SMC_NLA_LGR_R_ID, *((u32 *)&lgr->id)))
 343                 goto errattr;
 344         if (nla_put_u32(skb, SMC_NLA_LGR_R_CONNS_NUM, lgr->conns_num))
 345                 goto errattr;
 346         if (nla_put_u8(skb, SMC_NLA_LGR_R_ROLE, lgr->role))
 347                 goto errattr;
 348         if (nla_put_u8(skb, SMC_NLA_LGR_R_TYPE, lgr->type))
 349                 goto errattr;
 350         if (nla_put_u8(skb, SMC_NLA_LGR_R_VLAN_ID, lgr->vlan_id))
 351                 goto errattr;
 352         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_R_NET_COOKIE,
 353                               lgr->net->net_cookie, SMC_NLA_LGR_R_PAD))
 354                 goto errattr;
 355         memcpy(smc_target, lgr->pnet_id, SMC_MAX_PNETID_LEN);
 356         smc_target[SMC_MAX_PNETID_LEN] = 0;
 357         if (nla_put_string(skb, SMC_NLA_LGR_R_PNETID, smc_target))
 358                 goto errattr;
 359         if (lgr->smc_version > SMC_V1) {
 360                 v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2_COMMON);
 361                 if (!v2_attrs)
 362                         goto errattr;
 363                 if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
 364                         goto errattr;
 365                 if (smc_nl_fill_smcr_lgr_v2(lgr, skb, cb))
 366                         goto errattr;
 367         }
 368
 369         nla_nest_end(skb, attrs);
 370         return 0;
 371 errattr:
 372         nla_nest_cancel(skb, attrs);
 373 errout:
 374         return -EMSGSIZE;
 375 }
 376
 377 static int smc_nl_fill_lgr_link(struct smc_link_group *lgr,
 378                                 struct smc_link *link,
 379                                 struct sk_buff *skb,
 380                                 struct netlink_callback *cb)
 381 {
 382         char smc_ibname[IB_DEVICE_NAME_MAX];
 383         u8 smc_gid_target[41];
 384         struct nlattr *attrs;
 385         u32 link_uid = 0;
 386         void *nlh;
 387
 388         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 389                           &smc_gen_nl_family, NLM_F_MULTI,
 390                           SMC_NETLINK_GET_LINK_SMCR);
 391         if (!nlh)
 392                 goto errmsg;
 393
 394         attrs = nla_nest_start(skb, SMC_GEN_LINK_SMCR);
 395         if (!attrs)
 396                 goto errout;
 397
 398         if (nla_put_u8(skb, SMC_NLA_LINK_ID, link->link_id))
 399                 goto errattr;
 400         if (nla_put_u32(skb, SMC_NLA_LINK_STATE, link->state))
 401                 goto errattr;
 402         if (nla_put_u32(skb, SMC_NLA_LINK_CONN_CNT,
 403                         atomic_read(&link->conn_cnt)))
 404                 goto errattr;
 405         if (nla_put_u8(skb, SMC_NLA_LINK_IB_PORT, link->ibport))
 406                 goto errattr;
 407         if (nla_put_u32(skb, SMC_NLA_LINK_NET_DEV, link->ndev_ifidx))
 408                 goto errattr;
 409         snprintf(smc_ibname, sizeof(smc_ibname), "%s", link->ibname);
 410         if (nla_put_string(skb, SMC_NLA_LINK_IB_DEV, smc_ibname))
 411                 goto errattr;
 412         memcpy(&link_uid, link->link_uid, sizeof(link_uid));
 413         if (nla_put_u32(skb, SMC_NLA_LINK_UID, link_uid))
 414                 goto errattr;
 415         memcpy(&link_uid, link->peer_link_uid, sizeof(link_uid));
 416         if (nla_put_u32(skb, SMC_NLA_LINK_PEER_UID, link_uid))
 417                 goto errattr;
 418         memset(smc_gid_target, 0, sizeof(smc_gid_target));
 419         smc_gid_be16_convert(smc_gid_target, link->gid);
 420         if (nla_put_string(skb, SMC_NLA_LINK_GID, smc_gid_target))
 421                 goto errattr;
 422         memset(smc_gid_target, 0, sizeof(smc_gid_target));
 423         smc_gid_be16_convert(smc_gid_target, link->peer_gid);
 424         if (nla_put_string(skb, SMC_NLA_LINK_PEER_GID, smc_gid_target))
 425                 goto errattr;
 426
 427         nla_nest_end(skb, attrs);
 428         genlmsg_end(skb, nlh);
 429         return 0;
 430 errattr:
 431         nla_nest_cancel(skb, attrs);
 432 errout:
 433         genlmsg_cancel(skb, nlh);
 434 errmsg:
 435         return -EMSGSIZE;
 436 }
 437
 438 static int smc_nl_handle_lgr(struct smc_link_group *lgr,
 439                              struct sk_buff *skb,
 440                              struct netlink_callback *cb,
 441                              bool list_links)
 442 {
 443         void *nlh;
 444         int i;
 445
 446         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 447                           &smc_gen_nl_family, NLM_F_MULTI,
 448                           SMC_NETLINK_GET_LGR_SMCR);
 449         if (!nlh)
 450                 goto errmsg;
 451         if (smc_nl_fill_lgr(lgr, skb, cb))
 452                 goto errout;
 453
 454         genlmsg_end(skb, nlh);
 455         if (!list_links)
 456                 goto out;
 457         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 458                 if (!smc_link_usable(&lgr->lnk[i]))
 459                         continue;
 460                 if (smc_nl_fill_lgr_link(lgr, &lgr->lnk[i], skb, cb))
 461                         goto errout;
 462         }
 463 out:
 464         return 0;
 465
 466 errout:
 467         genlmsg_cancel(skb, nlh);
 468 errmsg:
 469         return -EMSGSIZE;
 470 }
 471
 472 static void smc_nl_fill_lgr_list(struct smc_lgr_list *smc_lgr,
 473                                  struct sk_buff *skb,
 474                                  struct netlink_callback *cb,
 475                                  bool list_links)
 476 {
 477         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 478         struct smc_link_group *lgr;
 479         int snum = cb_ctx->pos[0];
 480         int num = 0;
 481
 482         spin_lock_bh(&smc_lgr->lock);
 483         list_for_each_entry(lgr, &smc_lgr->list, list) {
 484                 if (num < snum)
 485                         goto next;
 486                 if (smc_nl_handle_lgr(lgr, skb, cb, list_links))
 487                         goto errout;
 488 next:
 489                 num++;
 490         }
 491 errout:
 492         spin_unlock_bh(&smc_lgr->lock);
 493         cb_ctx->pos[0] = num;
 494 }
 495
 496 static int smc_nl_fill_smcd_lgr(struct smc_link_group *lgr,
 497                                 struct sk_buff *skb,
 498                                 struct netlink_callback *cb)
 499 {
 500         char smc_pnet[SMC_MAX_PNETID_LEN + 1];
 501         struct nlattr *attrs;
 502         void *nlh;
 503
 504         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 505                           &smc_gen_nl_family, NLM_F_MULTI,
 506                           SMC_NETLINK_GET_LGR_SMCD);
 507         if (!nlh)
 508                 goto errmsg;
 509
 510         attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCD);
 511         if (!attrs)
 512                 goto errout;
 513
 514         if (nla_put_u32(skb, SMC_NLA_LGR_D_ID, *((u32 *)&lgr->id)))
 515                 goto errattr;
 516         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_GID, lgr->smcd->local_gid,
 517                               SMC_NLA_LGR_D_PAD))
 518                 goto errattr;
 519         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_GID, lgr->peer_gid,
 520                               SMC_NLA_LGR_D_PAD))
 521                 goto errattr;
 522         if (nla_put_u8(skb, SMC_NLA_LGR_D_VLAN_ID, lgr->vlan_id))
 523                 goto errattr;
 524         if (nla_put_u32(skb, SMC_NLA_LGR_D_CONNS_NUM, lgr->conns_num))
 525                 goto errattr;
 526         if (nla_put_u32(skb, SMC_NLA_LGR_D_CHID, smc_ism_get_chid(lgr->smcd)))
 527                 goto errattr;
 528         memcpy(smc_pnet, lgr->smcd->pnetid, SMC_MAX_PNETID_LEN);
 529         smc_pnet[SMC_MAX_PNETID_LEN] = 0;
 530         if (nla_put_string(skb, SMC_NLA_LGR_D_PNETID, smc_pnet))
 531                 goto errattr;
 532         if (lgr->smc_version > SMC_V1) {
 533                 struct nlattr *v2_attrs;
 534
 535                 v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_D_V2_COMMON);
 536                 if (!v2_attrs)
 537                         goto errattr;
 538                 if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
 539                         goto errattr;
 540         }
 541         nla_nest_end(skb, attrs);
 542         genlmsg_end(skb, nlh);
 543         return 0;
 544
 545 errattr:
 546         nla_nest_cancel(skb, attrs);
 547 errout:
 548         genlmsg_cancel(skb, nlh);
 549 errmsg:
 550         return -EMSGSIZE;
 551 }
 552
 553 static int smc_nl_handle_smcd_lgr(struct smcd_dev *dev,
 554                                   struct sk_buff *skb,
 555                                   struct netlink_callback *cb)
 556 {
 557         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 558         struct smc_link_group *lgr;
 559         int snum = cb_ctx->pos[1];
 560         int rc = 0, num = 0;
 561
 562         spin_lock_bh(&dev->lgr_lock);
 563         list_for_each_entry(lgr, &dev->lgr_list, list) {
 564                 if (!lgr->is_smcd)
 565                         continue;
 566                 if (num < snum)
 567                         goto next;
 568                 rc = smc_nl_fill_smcd_lgr(lgr, skb, cb);
 569                 if (rc)
 570                         goto errout;
 571 next:
 572                 num++;
 573         }
 574 errout:
 575         spin_unlock_bh(&dev->lgr_lock);
 576         cb_ctx->pos[1] = num;
 577         return rc;
 578 }
 579
 580 static int smc_nl_fill_smcd_dev(struct smcd_dev_list *dev_list,
 581                                 struct sk_buff *skb,
 582                                 struct netlink_callback *cb)
 583 {
 584         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 585         struct smcd_dev *smcd_dev;
 586         int snum = cb_ctx->pos[0];
 587         int rc = 0, num = 0;
 588
 589         mutex_lock(&dev_list->mutex);
 590         list_for_each_entry(smcd_dev, &dev_list->list, list) {
 591                 if (list_empty(&smcd_dev->lgr_list))
 592                         continue;
 593                 if (num < snum)
 594                         goto next;
 595                 rc = smc_nl_handle_smcd_lgr(smcd_dev, skb, cb);
 596                 if (rc)
 597                         goto errout;
 598 next:
 599                 num++;
 600         }
 601 errout:
 602         mutex_unlock(&dev_list->mutex);
 603         cb_ctx->pos[0] = num;
 604         return rc;
 605 }
 606
 607 int smcr_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
 608 {
 609         bool list_links = false;
 610
 611         smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
 612         return skb->len;
 613 }
 614
 615 int smcr_nl_get_link(struct sk_buff *skb, struct netlink_callback *cb)
 616 {
 617         bool list_links = true;
 618
 619         smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
 620         return skb->len;
 621 }
 622
 623 int smcd_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
 624 {
 625         smc_nl_fill_smcd_dev(&smcd_dev_list, skb, cb);
 626         return skb->len;
 627 }
 628
 629 void smc_lgr_cleanup_early(struct smc_link_group *lgr)
 630 {
 631         spinlock_t *lgr_lock;
 632
 633         if (!lgr)
 634                 return;
 635
 636         smc_lgr_list_head(lgr, &lgr_lock);
 637         spin_lock_bh(lgr_lock);
 638         /* do not use this link group for new connections */
 639         if (!list_empty(&lgr->list))
 640                 list_del_init(&lgr->list);
 641         spin_unlock_bh(lgr_lock);
 642         __smc_lgr_terminate(lgr, true);
 643 }
 644
 645 static void smcr_lgr_link_deactivate_all(struct smc_link_group *lgr)
 646 {
 647         int i;
 648
 649         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 650                 struct smc_link *lnk = &lgr->lnk[i];
 651
 652                 if (smc_link_sendable(lnk))
 653                         lnk->state = SMC_LNK_INACTIVE;
 654         }
 655         wake_up_all(&lgr->llc_msg_waiter);
 656         wake_up_all(&lgr->llc_flow_waiter);
 657 }
 658
 659 static void smc_lgr_free(struct smc_link_group *lgr);
 660
 661 static void smc_lgr_free_work(struct work_struct *work)
 662 {
 663         struct smc_link_group *lgr = container_of(to_delayed_work(work),
 664                                                   struct smc_link_group,
 665                                                   free_work);
 666         spinlock_t *lgr_lock;
 667         bool conns;
 668
 669         smc_lgr_list_head(lgr, &lgr_lock);
 670         spin_lock_bh(lgr_lock);
 671         if (lgr->freeing) {
 672                 spin_unlock_bh(lgr_lock);
 673                 return;
 674         }
 675         read_lock_bh(&lgr->conns_lock);
 676         conns = RB_EMPTY_ROOT(&lgr->conns_all);
 677         read_unlock_bh(&lgr->conns_lock);
 678         if (!conns) { /* number of lgr connections is no longer zero */
 679                 spin_unlock_bh(lgr_lock);
 680                 return;
 681         }
 682         list_del_init(&lgr->list); /* remove from smc_lgr_list */
 683         lgr->freeing = 1; /* this instance does the freeing, no new schedule */
 684         spin_unlock_bh(lgr_lock);
 685         cancel_delayed_work(&lgr->free_work);
 686
 687         if (!lgr->is_smcd && !lgr->terminating)
 688                 smc_llc_send_link_delete_all(lgr, true,
 689                                              SMC_LLC_DEL_PROG_INIT_TERM);
 690         if (lgr->is_smcd && !lgr->terminating)
 691                 smc_ism_signal_shutdown(lgr);
 692         if (!lgr->is_smcd)
 693                 smcr_lgr_link_deactivate_all(lgr);
 694         smc_lgr_free(lgr);
 695 }
 696
 697 static void smc_lgr_terminate_work(struct work_struct *work)
 698 {
 699         struct smc_link_group *lgr = container_of(work, struct smc_link_group,
 700                                                   terminate_work);
 701
 702         __smc_lgr_terminate(lgr, true);
 703 }
 704
 705 /* return next unique link id for the lgr */
 706 static u8 smcr_next_link_id(struct smc_link_group *lgr)
 707 {
 708         u8 link_id;
 709         int i;
 710
 711         while (1) {
 712 again:
 713                 link_id = ++lgr->next_link_id;
 714                 if (!link_id)   /* skip zero as link_id */
 715                         link_id = ++lgr->next_link_id;
 716                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 717                         if (smc_link_usable(&lgr->lnk[i]) &&
 718                             lgr->lnk[i].link_id == link_id)
 719                                 goto again;
 720                 }
 721                 break;
 722         }
 723         return link_id;
 724 }
 725
 726 static void smcr_copy_dev_info_to_link(struct smc_link *link)
 727 {
 728         struct smc_ib_device *smcibdev = link->smcibdev;
 729
 730         snprintf(link->ibname, sizeof(link->ibname), "%s",
 731                  smcibdev->ibdev->name);
 732         link->ndev_ifidx = smcibdev->ndev_ifidx[link->ibport - 1];
 733 }
 734
 735 int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
 736                    u8 link_idx, struct smc_init_info *ini)
 737 {
 738         struct smc_ib_device *smcibdev;
 739         u8 rndvec[3];
 740         int rc;
 741
 742         if (lgr->smc_version == SMC_V2) {
 743                 lnk->smcibdev = ini->smcrv2.ib_dev_v2;
 744                 lnk->ibport = ini->smcrv2.ib_port_v2;
 745         } else {
 746                 lnk->smcibdev = ini->ib_dev;
 747                 lnk->ibport = ini->ib_port;
 748         }
 749         get_device(&lnk->smcibdev->ibdev->dev);
 750         atomic_inc(&lnk->smcibdev->lnk_cnt);
 751         refcount_set(&lnk->refcnt, 1); /* link refcnt is set to 1 */
 752         lnk->clearing = 0;
 753         lnk->path_mtu = lnk->smcibdev->pattr[lnk->ibport - 1].active_mtu;
 754         lnk->link_id = smcr_next_link_id(lgr);
 755         lnk->lgr = lgr;
 756         smc_lgr_hold(lgr); /* lgr_put in smcr_link_clear() */
 757         lnk->link_idx = link_idx;
 758         smc_ibdev_cnt_inc(lnk);
 759         smcr_copy_dev_info_to_link(lnk);
 760         atomic_set(&lnk->conn_cnt, 0);
 761         smc_llc_link_set_uid(lnk);
 762         INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
 763         if (!lnk->smcibdev->initialized) {
 764                 rc = (int)smc_ib_setup_per_ibdev(lnk->smcibdev);
 765                 if (rc)
 766                         goto out;
 767         }
 768         get_random_bytes(rndvec, sizeof(rndvec));
 769         lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) +
 770                 (rndvec[2] << 16);
 771         rc = smc_ib_determine_gid(lnk->smcibdev, lnk->ibport,
 772                                   ini->vlan_id, lnk->gid, &lnk->sgid_index,
 773                                   lgr->smc_version == SMC_V2 ?
 774                                                   &ini->smcrv2 : NULL);
 775         if (rc)
 776                 goto out;
 777         rc = smc_llc_link_init(lnk);
 778         if (rc)
 779                 goto out;
 780         rc = smc_wr_alloc_link_mem(lnk);
 781         if (rc)
 782                 goto clear_llc_lnk;
 783         rc = smc_ib_create_protection_domain(lnk);
 784         if (rc)
 785                 goto free_link_mem;
 786         rc = smc_ib_create_queue_pair(lnk);
 787         if (rc)
 788                 goto dealloc_pd;
 789         rc = smc_wr_create_link(lnk);
 790         if (rc)
 791                 goto destroy_qp;
 792         lnk->state = SMC_LNK_ACTIVATING;
 793         return 0;
 794
 795 destroy_qp:
 796         smc_ib_destroy_queue_pair(lnk);
 797 dealloc_pd:
 798         smc_ib_dealloc_protection_domain(lnk);
 799 free_link_mem:
 800         smc_wr_free_link_mem(lnk);
 801 clear_llc_lnk:
 802         smc_llc_link_clear(lnk, false);
 803 out:
 804         smc_ibdev_cnt_dec(lnk);
 805         put_device(&lnk->smcibdev->ibdev->dev);
 806         smcibdev = lnk->smcibdev;
 807         memset(lnk, 0, sizeof(struct smc_link));
 808         lnk->state = SMC_LNK_UNUSED;
 809         if (!atomic_dec_return(&smcibdev->lnk_cnt))
 810                 wake_up(&smcibdev->lnks_deleted);
 811         smc_lgr_put(lgr); /* lgr_hold above */
 812         return rc;
 813 }
 814
 815 /* create a new SMC link group */
 816 static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
 817 {
 818         struct smc_link_group *lgr;
 819         struct list_head *lgr_list;
 820         struct smc_link *lnk;
 821         spinlock_t *lgr_lock;
 822         u8 link_idx;
 823         int rc = 0;
 824         int i;
 825
 826         if (ini->is_smcd && ini->vlan_id) {
 827                 if (smc_ism_get_vlan(ini->ism_dev[ini->ism_selected],
 828                                      ini->vlan_id)) {
 829                         rc = SMC_CLC_DECL_ISMVLANERR;
 830                         goto out;
 831                 }
 832         }
 833
 834         lgr = kzalloc(sizeof(*lgr), GFP_KERNEL);
 835         if (!lgr) {
 836                 rc = SMC_CLC_DECL_MEM;
 837                 goto ism_put_vlan;
 838         }
 839         lgr->tx_wq = alloc_workqueue("smc_tx_wq-%*phN", 0, 0,
 840                                      SMC_LGR_ID_SIZE, &lgr->id);
 841         if (!lgr->tx_wq) {
 842                 rc = -ENOMEM;
 843                 goto free_lgr;
 844         }
 845         lgr->is_smcd = ini->is_smcd;
 846         lgr->sync_err = 0;
 847         lgr->terminating = 0;
 848         lgr->freeing = 0;
 849         lgr->vlan_id = ini->vlan_id;
 850         refcount_set(&lgr->refcnt, 1); /* set lgr refcnt to 1 */
 851         mutex_init(&lgr->sndbufs_lock);
 852         mutex_init(&lgr->rmbs_lock);
 853         rwlock_init(&lgr->conns_lock);
 854         for (i = 0; i < SMC_RMBE_SIZES; i++) {
 855                 INIT_LIST_HEAD(&lgr->sndbufs[i]);
 856                 INIT_LIST_HEAD(&lgr->rmbs[i]);
 857         }
 858         lgr->next_link_id = 0;
 859         smc_lgr_list.num += SMC_LGR_NUM_INCR;
 860         memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE);
 861         INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
 862         INIT_WORK(&lgr->terminate_work, smc_lgr_terminate_work);
 863         lgr->conns_all = RB_ROOT;
 864         if (ini->is_smcd) {
 865                 /* SMC-D specific settings */
 866                 get_device(&ini->ism_dev[ini->ism_selected]->dev);
 867                 lgr->peer_gid = ini->ism_peer_gid[ini->ism_selected];
 868                 lgr->smcd = ini->ism_dev[ini->ism_selected];
 869                 lgr_list = &ini->ism_dev[ini->ism_selected]->lgr_list;
 870                 lgr_lock = &lgr->smcd->lgr_lock;
 871                 lgr->smc_version = ini->smcd_version;
 872                 lgr->peer_shutdown = 0;
 873                 atomic_inc(&ini->ism_dev[ini->ism_selected]->lgr_cnt);
 874         } else {
 875                 /* SMC-R specific settings */
 876                 struct smc_ib_device *ibdev;
 877                 int ibport;
 878
 879                 lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
 880                 lgr->smc_version = ini->smcr_version;
 881                 memcpy(lgr->peer_systemid, ini->peer_systemid,
 882                        SMC_SYSTEMID_LEN);
 883                 if (lgr->smc_version == SMC_V2) {
 884                         ibdev = ini->smcrv2.ib_dev_v2;
 885                         ibport = ini->smcrv2.ib_port_v2;
 886                         lgr->saddr = ini->smcrv2.saddr;
 887                         lgr->uses_gateway = ini->smcrv2.uses_gateway;
 888                         memcpy(lgr->nexthop_mac, ini->smcrv2.nexthop_mac,
 889                                ETH_ALEN);
 890                 } else {
 891                         ibdev = ini->ib_dev;
 892                         ibport = ini->ib_port;
 893                 }
 894                 memcpy(lgr->pnet_id, ibdev->pnetid[ibport - 1],
 895                        SMC_MAX_PNETID_LEN);
 896                 if (smc_wr_alloc_lgr_mem(lgr))
 897                         goto free_wq;
 898                 smc_llc_lgr_init(lgr, smc);
 899
 900                 link_idx = SMC_SINGLE_LINK;
 901                 lnk = &lgr->lnk[link_idx];
 902                 rc = smcr_link_init(lgr, lnk, link_idx, ini);
 903                 if (rc) {
 904                         smc_wr_free_lgr_mem(lgr);
 905                         goto free_wq;
 906                 }
 907                 lgr->net = smc_ib_net(lnk->smcibdev);
 908                 lgr_list = &smc_lgr_list.list;
 909                 lgr_lock = &smc_lgr_list.lock;
 910                 atomic_inc(&lgr_cnt);
 911         }
 912         smc->conn.lgr = lgr;
 913         spin_lock_bh(lgr_lock);
 914         list_add_tail(&lgr->list, lgr_list);
 915         spin_unlock_bh(lgr_lock);
 916         return 0;
 917
 918 free_wq:
 919         destroy_workqueue(lgr->tx_wq);
 920 free_lgr:
 921         kfree(lgr);
 922 ism_put_vlan:
 923         if (ini->is_smcd && ini->vlan_id)
 924                 smc_ism_put_vlan(ini->ism_dev[ini->ism_selected], ini->vlan_id);
 925 out:
 926         if (rc < 0) {
 927                 if (rc == -ENOMEM)
 928                         rc = SMC_CLC_DECL_MEM;
 929                 else
 930                         rc = SMC_CLC_DECL_INTERR;
 931         }
 932         return rc;
 933 }
 934
 935 static int smc_write_space(struct smc_connection *conn)
 936 {
 937         int buffer_len = conn->peer_rmbe_size;
 938         union smc_host_cursor prod;
 939         union smc_host_cursor cons;
 940         int space;
 941
 942         smc_curs_copy(&prod, &conn->local_tx_ctrl.prod, conn);
 943         smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
 944         /* determine rx_buf space */
 945         space = buffer_len - smc_curs_diff(buffer_len, &cons, &prod);
 946         return space;
 947 }
 948
 949 static int smc_switch_cursor(struct smc_sock *smc, struct smc_cdc_tx_pend *pend,
 950                              struct smc_wr_buf *wr_buf)
 951 {
 952         struct smc_connection *conn = &smc->conn;
 953         union smc_host_cursor cons, fin;
 954         int rc = 0;
 955         int diff;
 956
 957         smc_curs_copy(&conn->tx_curs_sent, &conn->tx_curs_fin, conn);
 958         smc_curs_copy(&fin, &conn->local_tx_ctrl_fin, conn);
 959         /* set prod cursor to old state, enforce tx_rdma_writes() */
 960         smc_curs_copy(&conn->local_tx_ctrl.prod, &fin, conn);
 961         smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
 962
 963         if (smc_curs_comp(conn->peer_rmbe_size, &cons, &fin) < 0) {
 964                 /* cons cursor advanced more than fin, and prod was set
 965                  * fin above, so now prod is smaller than cons. Fix that.
 966                  */
 967                 diff = smc_curs_diff(conn->peer_rmbe_size, &fin, &cons);
 968                 smc_curs_add(conn->sndbuf_desc->len,
 969                              &conn->tx_curs_sent, diff);
 970                 smc_curs_add(conn->sndbuf_desc->len,
 971                              &conn->tx_curs_fin, diff);
 972
 973                 smp_mb__before_atomic();
 974                 atomic_add(diff, &conn->sndbuf_space);
 975                 smp_mb__after_atomic();
 976
 977                 smc_curs_add(conn->peer_rmbe_size,
 978                              &conn->local_tx_ctrl.prod, diff);
 979                 smc_curs_add(conn->peer_rmbe_size,
 980                              &conn->local_tx_ctrl_fin, diff);
 981         }
 982         /* recalculate, value is used by tx_rdma_writes() */
 983         atomic_set(&smc->conn.peer_rmbe_space, smc_write_space(conn));
 984
 985         if (smc->sk.sk_state != SMC_INIT &&
 986             smc->sk.sk_state != SMC_CLOSED) {
 987                 rc = smcr_cdc_msg_send_validation(conn, pend, wr_buf);
 988                 if (!rc) {
 989                         queue_delayed_work(conn->lgr->tx_wq, &conn->tx_work, 0);
 990                         smc->sk.sk_data_ready(&smc->sk);
 991                 }
 992         } else {
 993                 smc_wr_tx_put_slot(conn->lnk,
 994                                    (struct smc_wr_tx_pend_priv *)pend);
 995         }
 996         return rc;
 997 }
 998
 999 void smc_switch_link_and_count(struct smc_connection *conn,
1000                                struct smc_link *to_lnk)
1001 {
1002         atomic_dec(&conn->lnk->conn_cnt);
1003         /* link_hold in smc_conn_create() */
1004         smcr_link_put(conn->lnk);
1005         conn->lnk = to_lnk;
1006         atomic_inc(&conn->lnk->conn_cnt);
1007         /* link_put in smc_conn_free() */
1008         smcr_link_hold(conn->lnk);
1009 }
1010
1011 struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
1012                                   struct smc_link *from_lnk, bool is_dev_err)
1013 {
1014         struct smc_link *to_lnk = NULL;
1015         struct smc_cdc_tx_pend *pend;
1016         struct smc_connection *conn;
1017         struct smc_wr_buf *wr_buf;
1018         struct smc_sock *smc;
1019         struct rb_node *node;
1020         int i, rc = 0;
1021
1022         /* link is inactive, wake up tx waiters */
1023         smc_wr_wakeup_tx_wait(from_lnk);
1024
1025         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1026                 if (!smc_link_active(&lgr->lnk[i]) || i == from_lnk->link_idx)
1027                         continue;
1028                 if (is_dev_err && from_lnk->smcibdev == lgr->lnk[i].smcibdev &&
1029                     from_lnk->ibport == lgr->lnk[i].ibport) {
1030                         continue;
1031                 }
1032                 to_lnk = &lgr->lnk[i];
1033                 break;
1034         }
1035         if (!to_lnk || !smc_wr_tx_link_hold(to_lnk)) {
1036                 smc_lgr_terminate_sched(lgr);
1037                 return NULL;
1038         }
1039 again:
1040         read_lock_bh(&lgr->conns_lock);
1041         for (node = rb_first(&lgr->conns_all); node; node = rb_next(node)) {
1042                 conn = rb_entry(node, struct smc_connection, alert_node);
1043                 if (conn->lnk != from_lnk)
1044                         continue;
1045                 smc = container_of(conn, struct smc_sock, conn);
1046                 /* conn->lnk not yet set in SMC_INIT state */
1047                 if (smc->sk.sk_state == SMC_INIT)
1048                         continue;
1049                 if (smc->sk.sk_state == SMC_CLOSED ||
1050                     smc->sk.sk_state == SMC_PEERCLOSEWAIT1 ||
1051                     smc->sk.sk_state == SMC_PEERCLOSEWAIT2 ||
1052                     smc->sk.sk_state == SMC_APPFINCLOSEWAIT ||
1053                     smc->sk.sk_state == SMC_APPCLOSEWAIT1 ||
1054                     smc->sk.sk_state == SMC_APPCLOSEWAIT2 ||
1055                     smc->sk.sk_state == SMC_PEERFINCLOSEWAIT ||
1056                     smc->sk.sk_state == SMC_PEERABORTWAIT ||
1057                     smc->sk.sk_state == SMC_PROCESSABORT) {
1058                         spin_lock_bh(&conn->send_lock);
1059                         smc_switch_link_and_count(conn, to_lnk);
1060                         spin_unlock_bh(&conn->send_lock);
1061                         continue;
1062                 }
1063                 sock_hold(&smc->sk);
1064                 read_unlock_bh(&lgr->conns_lock);
1065                 /* pre-fetch buffer outside of send_lock, might sleep */
1066                 rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend);
1067                 if (rc)
1068                         goto err_out;
1069                 /* avoid race with smcr_tx_sndbuf_nonempty() */
1070                 spin_lock_bh(&conn->send_lock);
1071                 smc_switch_link_and_count(conn, to_lnk);
1072                 rc = smc_switch_cursor(smc, pend, wr_buf);
1073                 spin_unlock_bh(&conn->send_lock);
1074                 sock_put(&smc->sk);
1075                 if (rc)
1076                         goto err_out;
1077                 goto again;
1078         }
1079         read_unlock_bh(&lgr->conns_lock);
1080         smc_wr_tx_link_put(to_lnk);
1081         return to_lnk;
1082
1083 err_out:
1084         smcr_link_down_cond_sched(to_lnk);
1085         smc_wr_tx_link_put(to_lnk);
1086         return NULL;
1087 }
1088
1089 static void smcr_buf_unuse(struct smc_buf_desc *rmb_desc,
1090                            struct smc_link_group *lgr)
1091 {
1092         int rc;
1093
1094         if (rmb_desc->is_conf_rkey && !list_empty(&lgr->list)) {
1095                 /* unregister rmb with peer */
1096                 rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
1097                 if (!rc) {
1098                         /* protect against smc_llc_cli_rkey_exchange() */
1099                         mutex_lock(&lgr->llc_conf_mutex);
1100                         smc_llc_do_delete_rkey(lgr, rmb_desc);
1101                         rmb_desc->is_conf_rkey = false;
1102                         mutex_unlock(&lgr->llc_conf_mutex);
1103                         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
1104                 }
1105         }
1106
1107         if (rmb_desc->is_reg_err) {
1108                 /* buf registration failed, reuse not possible */
1109                 mutex_lock(&lgr->rmbs_lock);
1110                 list_del(&rmb_desc->list);
1111                 mutex_unlock(&lgr->rmbs_lock);
1112
1113                 smc_buf_free(lgr, true, rmb_desc);
1114         } else {
1115                 rmb_desc->used = 0;
1116                 memset(rmb_desc->cpu_addr, 0, rmb_desc->len);
1117         }
1118 }
1119
1120 static void smc_buf_unuse(struct smc_connection *conn,
1121                           struct smc_link_group *lgr)
1122 {
1123         if (conn->sndbuf_desc) {
1124                 conn->sndbuf_desc->used = 0;
1125                 memset(conn->sndbuf_desc->cpu_addr, 0, conn->sndbuf_desc->len);
1126         }
1127         if (conn->rmb_desc && lgr->is_smcd) {
1128                 conn->rmb_desc->used = 0;
1129                 memset(conn->rmb_desc->cpu_addr, 0, conn->rmb_desc->len +
1130                        sizeof(struct smcd_cdc_msg));
1131         } else if (conn->rmb_desc) {
1132                 smcr_buf_unuse(conn->rmb_desc, lgr);
1133         }
1134 }
1135
1136 /* remove a finished connection from its link group */
1137 void smc_conn_free(struct smc_connection *conn)
1138 {
1139         struct smc_link_group *lgr = conn->lgr;
1140
1141         if (!lgr || conn->freed)
1142                 /* Connection has never been registered in a
1143                  * link group, or has already been freed.
1144                  */
1145                 return;
1146
1147         conn->freed = 1;
1148         if (!smc_conn_lgr_valid(conn))
1149                 /* Connection has already unregistered from
1150                  * link group.
1151                  */
1152                 goto lgr_put;
1153
1154         if (lgr->is_smcd) {
1155                 if (!list_empty(&lgr->list))
1156                         smc_ism_unset_conn(conn);
1157                 tasklet_kill(&conn->rx_tsklet);
1158         } else {
1159                 smc_cdc_wait_pend_tx_wr(conn);
1160                 if (current_work() != &conn->abort_work)
1161                         cancel_work_sync(&conn->abort_work);
1162         }
1163         if (!list_empty(&lgr->list)) {
1164                 smc_lgr_unregister_conn(conn);
1165                 smc_buf_unuse(conn, lgr); /* allow buffer reuse */
1166         }
1167
1168         if (!lgr->conns_num)
1169                 smc_lgr_schedule_free_work(lgr);
1170 lgr_put:
1171         if (!lgr->is_smcd)
1172                 smcr_link_put(conn->lnk); /* link_hold in smc_conn_create() */
1173         smc_lgr_put(lgr); /* lgr_hold in smc_conn_create() */
1174 }
1175
1176 /* unregister a link from a buf_desc */
1177 static void smcr_buf_unmap_link(struct smc_buf_desc *buf_desc, bool is_rmb,
1178                                 struct smc_link *lnk)
1179 {
1180         if (is_rmb)
1181                 buf_desc->is_reg_mr[lnk->link_idx] = false;
1182         if (!buf_desc->is_map_ib[lnk->link_idx])
1183                 return;
1184         if (is_rmb) {
1185                 if (buf_desc->mr_rx[lnk->link_idx]) {
1186                         smc_ib_put_memory_region(
1187                                         buf_desc->mr_rx[lnk->link_idx]);
1188                         buf_desc->mr_rx[lnk->link_idx] = NULL;
1189                 }
1190                 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_FROM_DEVICE);
1191         } else {
1192                 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_TO_DEVICE);
1193         }
1194         sg_free_table(&buf_desc->sgt[lnk->link_idx]);
1195         buf_desc->is_map_ib[lnk->link_idx] = false;
1196 }
1197
1198 /* unmap all buffers of lgr for a deleted link */
1199 static void smcr_buf_unmap_lgr(struct smc_link *lnk)
1200 {
1201         struct smc_link_group *lgr = lnk->lgr;
1202         struct smc_buf_desc *buf_desc, *bf;
1203         int i;
1204
1205         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1206                 mutex_lock(&lgr->rmbs_lock);
1207                 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list)
1208                         smcr_buf_unmap_link(buf_desc, true, lnk);
1209                 mutex_unlock(&lgr->rmbs_lock);
1210                 mutex_lock(&lgr->sndbufs_lock);
1211                 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i],
1212                                          list)
1213                         smcr_buf_unmap_link(buf_desc, false, lnk);
1214                 mutex_unlock(&lgr->sndbufs_lock);
1215         }
1216 }
1217
1218 static void smcr_rtoken_clear_link(struct smc_link *lnk)
1219 {
1220         struct smc_link_group *lgr = lnk->lgr;
1221         int i;
1222
1223         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1224                 lgr->rtokens[i][lnk->link_idx].rkey = 0;
1225                 lgr->rtokens[i][lnk->link_idx].dma_addr = 0;
1226         }
1227 }
1228
1229 static void __smcr_link_clear(struct smc_link *lnk)
1230 {
1231         struct smc_link_group *lgr = lnk->lgr;
1232         struct smc_ib_device *smcibdev;
1233
1234         smc_wr_free_link_mem(lnk);
1235         smc_ibdev_cnt_dec(lnk);
1236         put_device(&lnk->smcibdev->ibdev->dev);
1237         smcibdev = lnk->smcibdev;
1238         memset(lnk, 0, sizeof(struct smc_link));
1239         lnk->state = SMC_LNK_UNUSED;
1240         if (!atomic_dec_return(&smcibdev->lnk_cnt))
1241                 wake_up(&smcibdev->lnks_deleted);
1242         smc_lgr_put(lgr); /* lgr_hold in smcr_link_init() */
1243 }
1244
1245 /* must be called under lgr->llc_conf_mutex lock */
1246 void smcr_link_clear(struct smc_link *lnk, bool log)
1247 {
1248         if (!lnk->lgr || lnk->clearing ||
1249             lnk->state == SMC_LNK_UNUSED)
1250                 return;
1251         lnk->clearing = 1;
1252         lnk->peer_qpn = 0;
1253         smc_llc_link_clear(lnk, log);
1254         smcr_buf_unmap_lgr(lnk);
1255         smcr_rtoken_clear_link(lnk);
1256         smc_ib_modify_qp_error(lnk);
1257         smc_wr_free_link(lnk);
1258         smc_ib_destroy_queue_pair(lnk);
1259         smc_ib_dealloc_protection_domain(lnk);
1260         smcr_link_put(lnk); /* theoretically last link_put */
1261 }
1262
1263 void smcr_link_hold(struct smc_link *lnk)
1264 {
1265         refcount_inc(&lnk->refcnt);
1266 }
1267
1268 void smcr_link_put(struct smc_link *lnk)
1269 {
1270         if (refcount_dec_and_test(&lnk->refcnt))
1271                 __smcr_link_clear(lnk);
1272 }
1273
1274 static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb,
1275                           struct smc_buf_desc *buf_desc)
1276 {
1277         int i;
1278
1279         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1280                 smcr_buf_unmap_link(buf_desc, is_rmb, &lgr->lnk[i]);
1281
1282         if (buf_desc->pages)
1283                 __free_pages(buf_desc->pages, buf_desc->order);
1284         kfree(buf_desc);
1285 }
1286
1287 static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb,
1288                           struct smc_buf_desc *buf_desc)
1289 {
1290         if (is_dmb) {
1291                 /* restore original buf len */
1292                 buf_desc->len += sizeof(struct smcd_cdc_msg);
1293                 smc_ism_unregister_dmb(lgr->smcd, buf_desc);
1294         } else {
1295                 kfree(buf_desc->cpu_addr);
1296         }
1297         kfree(buf_desc);
1298 }
1299
1300 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
1301                          struct smc_buf_desc *buf_desc)
1302 {
1303         if (lgr->is_smcd)
1304                 smcd_buf_free(lgr, is_rmb, buf_desc);
1305         else
1306                 smcr_buf_free(lgr, is_rmb, buf_desc);
1307 }
1308
1309 static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb)
1310 {
1311         struct smc_buf_desc *buf_desc, *bf_desc;
1312         struct list_head *buf_list;
1313         int i;
1314
1315         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1316                 if (is_rmb)
1317                         buf_list = &lgr->rmbs[i];
1318                 else
1319                         buf_list = &lgr->sndbufs[i];
1320                 list_for_each_entry_safe(buf_desc, bf_desc, buf_list,
1321                                          list) {
1322                         list_del(&buf_desc->list);
1323                         smc_buf_free(lgr, is_rmb, buf_desc);
1324                 }
1325         }
1326 }
1327
1328 static void smc_lgr_free_bufs(struct smc_link_group *lgr)
1329 {
1330         /* free send buffers */
1331         __smc_lgr_free_bufs(lgr, false);
1332         /* free rmbs */
1333         __smc_lgr_free_bufs(lgr, true);
1334 }
1335
1336 /* won't be freed until no one accesses to lgr anymore */
1337 static void __smc_lgr_free(struct smc_link_group *lgr)
1338 {
1339         smc_lgr_free_bufs(lgr);
1340         if (lgr->is_smcd) {
1341                 if (!atomic_dec_return(&lgr->smcd->lgr_cnt))
1342                         wake_up(&lgr->smcd->lgrs_deleted);
1343         } else {
1344                 smc_wr_free_lgr_mem(lgr);
1345                 if (!atomic_dec_return(&lgr_cnt))
1346                         wake_up(&lgrs_deleted);
1347         }
1348         kfree(lgr);
1349 }
1350
1351 /* remove a link group */
1352 static void smc_lgr_free(struct smc_link_group *lgr)
1353 {
1354         int i;
1355
1356         if (!lgr->is_smcd) {
1357                 mutex_lock(&lgr->llc_conf_mutex);
1358                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1359                         if (lgr->lnk[i].state != SMC_LNK_UNUSED)
1360                                 smcr_link_clear(&lgr->lnk[i], false);
1361                 }
1362                 mutex_unlock(&lgr->llc_conf_mutex);
1363                 smc_llc_lgr_clear(lgr);
1364         }
1365
1366         destroy_workqueue(lgr->tx_wq);
1367         if (lgr->is_smcd) {
1368                 smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
1369                 put_device(&lgr->smcd->dev);
1370         }
1371         smc_lgr_put(lgr); /* theoretically last lgr_put */
1372 }
1373
1374 void smc_lgr_hold(struct smc_link_group *lgr)
1375 {
1376         refcount_inc(&lgr->refcnt);
1377 }
1378
1379 void smc_lgr_put(struct smc_link_group *lgr)
1380 {
1381         if (refcount_dec_and_test(&lgr->refcnt))
1382                 __smc_lgr_free(lgr);
1383 }
1384
1385 static void smc_sk_wake_ups(struct smc_sock *smc)
1386 {
1387         smc->sk.sk_write_space(&smc->sk);
1388         smc->sk.sk_data_ready(&smc->sk);
1389         smc->sk.sk_state_change(&smc->sk);
1390 }
1391
1392 /* kill a connection */
1393 static void smc_conn_kill(struct smc_connection *conn, bool soft)
1394 {
1395         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1396
1397         if (conn->lgr->is_smcd && conn->lgr->peer_shutdown)
1398                 conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
1399         else
1400                 smc_close_abort(conn);
1401         conn->killed = 1;
1402         smc->sk.sk_err = ECONNABORTED;
1403         smc_sk_wake_ups(smc);
1404         if (conn->lgr->is_smcd) {
1405                 smc_ism_unset_conn(conn);
1406                 if (soft)
1407                         tasklet_kill(&conn->rx_tsklet);
1408                 else
1409                         tasklet_unlock_wait(&conn->rx_tsklet);
1410         } else {
1411                 smc_cdc_wait_pend_tx_wr(conn);
1412         }
1413         smc_lgr_unregister_conn(conn);
1414         smc_close_active_abort(smc);
1415 }
1416
1417 static void smc_lgr_cleanup(struct smc_link_group *lgr)
1418 {
1419         if (lgr->is_smcd) {
1420                 smc_ism_signal_shutdown(lgr);
1421         } else {
1422                 u32 rsn = lgr->llc_termination_rsn;
1423
1424                 if (!rsn)
1425                         rsn = SMC_LLC_DEL_PROG_INIT_TERM;
1426                 smc_llc_send_link_delete_all(lgr, false, rsn);
1427                 smcr_lgr_link_deactivate_all(lgr);
1428         }
1429 }
1430
1431 /* terminate link group
1432  * @soft: true if link group shutdown can take its time
1433  *        false if immediate link group shutdown is required
1434  */
1435 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft)
1436 {
1437         struct smc_connection *conn;
1438         struct smc_sock *smc;
1439         struct rb_node *node;
1440
1441         if (lgr->terminating)
1442                 return; /* lgr already terminating */
1443         /* cancel free_work sync, will terminate when lgr->freeing is set */
1444         cancel_delayed_work_sync(&lgr->free_work);
1445         lgr->terminating = 1;
1446
1447         /* kill remaining link group connections */
1448         read_lock_bh(&lgr->conns_lock);
1449         node = rb_first(&lgr->conns_all);
1450         while (node) {
1451                 read_unlock_bh(&lgr->conns_lock);
1452                 conn = rb_entry(node, struct smc_connection, alert_node);
1453                 smc = container_of(conn, struct smc_sock, conn);
1454                 sock_hold(&smc->sk); /* sock_put below */
1455                 lock_sock(&smc->sk);
1456                 smc_conn_kill(conn, soft);
1457                 release_sock(&smc->sk);
1458                 sock_put(&smc->sk); /* sock_hold above */
1459                 read_lock_bh(&lgr->conns_lock);
1460                 node = rb_first(&lgr->conns_all);
1461         }
1462         read_unlock_bh(&lgr->conns_lock);
1463         smc_lgr_cleanup(lgr);
1464         smc_lgr_free(lgr);
1465 }
1466
1467 /* unlink link group and schedule termination */
1468 void smc_lgr_terminate_sched(struct smc_link_group *lgr)
1469 {
1470         spinlock_t *lgr_lock;
1471
1472         smc_lgr_list_head(lgr, &lgr_lock);
1473         spin_lock_bh(lgr_lock);
1474         if (list_empty(&lgr->list) || lgr->terminating || lgr->freeing) {
1475                 spin_unlock_bh(lgr_lock);
1476                 return; /* lgr already terminating */
1477         }
1478         list_del_init(&lgr->list);
1479         lgr->freeing = 1;
1480         spin_unlock_bh(lgr_lock);
1481         schedule_work(&lgr->terminate_work);
1482 }
1483
1484 /* Called when peer lgr shutdown (regularly or abnormally) is received */
1485 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
1486 {
1487         struct smc_link_group *lgr, *l;
1488         LIST_HEAD(lgr_free_list);
1489
1490         /* run common cleanup function and build free list */
1491         spin_lock_bh(&dev->lgr_lock);
1492         list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) {
1493                 if ((!peer_gid || lgr->peer_gid == peer_gid) &&
1494                     (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
1495                         if (peer_gid) /* peer triggered termination */
1496                                 lgr->peer_shutdown = 1;
1497                         list_move(&lgr->list, &lgr_free_list);
1498                         lgr->freeing = 1;
1499                 }
1500         }
1501         spin_unlock_bh(&dev->lgr_lock);
1502
1503         /* cancel the regular free workers and actually free lgrs */
1504         list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
1505                 list_del_init(&lgr->list);
1506                 schedule_work(&lgr->terminate_work);
1507         }
1508 }
1509
1510 /* Called when an SMCD device is removed or the smc module is unloaded */
1511 void smc_smcd_terminate_all(struct smcd_dev *smcd)
1512 {
1513         struct smc_link_group *lgr, *lg;
1514         LIST_HEAD(lgr_free_list);
1515
1516         spin_lock_bh(&smcd->lgr_lock);
1517         list_splice_init(&smcd->lgr_list, &lgr_free_list);
1518         list_for_each_entry(lgr, &lgr_free_list, list)
1519                 lgr->freeing = 1;
1520         spin_unlock_bh(&smcd->lgr_lock);
1521
1522         list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1523                 list_del_init(&lgr->list);
1524                 __smc_lgr_terminate(lgr, false);
1525         }
1526
1527         if (atomic_read(&smcd->lgr_cnt))
1528                 wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt));
1529 }
1530
1531 /* Called when an SMCR device is removed or the smc module is unloaded.
1532  * If smcibdev is given, all SMCR link groups using this device are terminated.
1533  * If smcibdev is NULL, all SMCR link groups are terminated.
1534  */
1535 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
1536 {
1537         struct smc_link_group *lgr, *lg;
1538         LIST_HEAD(lgr_free_list);
1539         int i;
1540
1541         spin_lock_bh(&smc_lgr_list.lock);
1542         if (!smcibdev) {
1543                 list_splice_init(&smc_lgr_list.list, &lgr_free_list);
1544                 list_for_each_entry(lgr, &lgr_free_list, list)
1545                         lgr->freeing = 1;
1546         } else {
1547                 list_for_each_entry_safe(lgr, lg, &smc_lgr_list.list, list) {
1548                         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1549                                 if (lgr->lnk[i].smcibdev == smcibdev)
1550                                         smcr_link_down_cond_sched(&lgr->lnk[i]);
1551                         }
1552                 }
1553         }
1554         spin_unlock_bh(&smc_lgr_list.lock);
1555
1556         list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1557                 list_del_init(&lgr->list);
1558                 smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_OP_INIT_TERM);
1559                 __smc_lgr_terminate(lgr, false);
1560         }
1561
1562         if (smcibdev) {
1563                 if (atomic_read(&smcibdev->lnk_cnt))
1564                         wait_event(smcibdev->lnks_deleted,
1565                                    !atomic_read(&smcibdev->lnk_cnt));
1566         } else {
1567                 if (atomic_read(&lgr_cnt))
1568                         wait_event(lgrs_deleted, !atomic_read(&lgr_cnt));
1569         }
1570 }
1571
1572 /* set new lgr type and clear all asymmetric link tagging */
1573 void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type)
1574 {
1575         char *lgr_type = "";
1576         int i;
1577
1578         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1579                 if (smc_link_usable(&lgr->lnk[i]))
1580                         lgr->lnk[i].link_is_asym = false;
1581         if (lgr->type == new_type)
1582                 return;
1583         lgr->type = new_type;
1584
1585         switch (lgr->type) {
1586         case SMC_LGR_NONE:
1587                 lgr_type = "NONE";
1588                 break;
1589         case SMC_LGR_SINGLE:
1590                 lgr_type = "SINGLE";
1591                 break;
1592         case SMC_LGR_SYMMETRIC:
1593                 lgr_type = "SYMMETRIC";
1594                 break;
1595         case SMC_LGR_ASYMMETRIC_PEER:
1596                 lgr_type = "ASYMMETRIC_PEER";
1597                 break;
1598         case SMC_LGR_ASYMMETRIC_LOCAL:
1599                 lgr_type = "ASYMMETRIC_LOCAL";
1600                 break;
1601         }
1602         pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu state changed: "
1603                             "%s, pnetid %.16s\n", SMC_LGR_ID_SIZE, &lgr->id,
1604                             lgr->net->net_cookie, lgr_type, lgr->pnet_id);
1605 }
1606
1607 /* set new lgr type and tag a link as asymmetric */
1608 void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
1609                             enum smc_lgr_type new_type, int asym_lnk_idx)
1610 {
1611         smcr_lgr_set_type(lgr, new_type);
1612         lgr->lnk[asym_lnk_idx].link_is_asym = true;
1613 }
1614
1615 /* abort connection, abort_work scheduled from tasklet context */
1616 static void smc_conn_abort_work(struct work_struct *work)
1617 {
1618         struct smc_connection *conn = container_of(work,
1619                                                    struct smc_connection,
1620                                                    abort_work);
1621         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1622
1623         lock_sock(&smc->sk);
1624         smc_conn_kill(conn, true);
1625         release_sock(&smc->sk);
1626         sock_put(&smc->sk); /* sock_hold done by schedulers of abort_work */
1627 }
1628
1629 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport)
1630 {
1631         struct smc_link_group *lgr, *n;
1632
1633         list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1634                 struct smc_link *link;
1635
1636                 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1637                             SMC_MAX_PNETID_LEN) ||
1638                     lgr->type == SMC_LGR_SYMMETRIC ||
1639                     lgr->type == SMC_LGR_ASYMMETRIC_PEER ||
1640                     !rdma_dev_access_netns(smcibdev->ibdev, lgr->net))
1641                         continue;
1642
1643                 /* trigger local add link processing */
1644                 link = smc_llc_usable_link(lgr);
1645                 if (link)
1646                         smc_llc_add_link_local(link);
1647         }
1648 }
1649
1650 /* link is down - switch connections to alternate link,
1651  * must be called under lgr->llc_conf_mutex lock
1652  */
1653 static void smcr_link_down(struct smc_link *lnk)
1654 {
1655         struct smc_link_group *lgr = lnk->lgr;
1656         struct smc_link *to_lnk;
1657         int del_link_id;
1658
1659         if (!lgr || lnk->state == SMC_LNK_UNUSED || list_empty(&lgr->list))
1660                 return;
1661
1662         to_lnk = smc_switch_conns(lgr, lnk, true);
1663         if (!to_lnk) { /* no backup link available */
1664                 smcr_link_clear(lnk, true);
1665                 return;
1666         }
1667         smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
1668         del_link_id = lnk->link_id;
1669
1670         if (lgr->role == SMC_SERV) {
1671                 /* trigger local delete link processing */
1672                 smc_llc_srv_delete_link_local(to_lnk, del_link_id);
1673         } else {
1674                 if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
1675                         /* another llc task is ongoing */
1676                         mutex_unlock(&lgr->llc_conf_mutex);
1677                         wait_event_timeout(lgr->llc_flow_waiter,
1678                                 (list_empty(&lgr->list) ||
1679                                  lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE),
1680                                 SMC_LLC_WAIT_TIME);
1681                         mutex_lock(&lgr->llc_conf_mutex);
1682                 }
1683                 if (!list_empty(&lgr->list)) {
1684                         smc_llc_send_delete_link(to_lnk, del_link_id,
1685                                                  SMC_LLC_REQ, true,
1686                                                  SMC_LLC_DEL_LOST_PATH);
1687                         smcr_link_clear(lnk, true);
1688                 }
1689                 wake_up(&lgr->llc_flow_waiter); /* wake up next waiter */
1690         }
1691 }
1692
1693 /* must be called under lgr->llc_conf_mutex lock */
1694 void smcr_link_down_cond(struct smc_link *lnk)
1695 {
1696         if (smc_link_downing(&lnk->state)) {
1697                 trace_smcr_link_down(lnk, __builtin_return_address(0));
1698                 smcr_link_down(lnk);
1699         }
1700 }
1701
1702 /* will get the lgr->llc_conf_mutex lock */
1703 void smcr_link_down_cond_sched(struct smc_link *lnk)
1704 {
1705         if (smc_link_downing(&lnk->state)) {
1706                 trace_smcr_link_down(lnk, __builtin_return_address(0));
1707                 schedule_work(&lnk->link_down_wrk);
1708         }
1709 }
1710
1711 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport)
1712 {
1713         struct smc_link_group *lgr, *n;
1714         int i;
1715
1716         list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1717                 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1718                             SMC_MAX_PNETID_LEN))
1719                         continue; /* lgr is not affected */
1720                 if (list_empty(&lgr->list))
1721                         continue;
1722                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1723                         struct smc_link *lnk = &lgr->lnk[i];
1724
1725                         if (smc_link_usable(lnk) &&
1726                             lnk->smcibdev == smcibdev && lnk->ibport == ibport)
1727                                 smcr_link_down_cond_sched(lnk);
1728                 }
1729         }
1730 }
1731
1732 static void smc_link_down_work(struct work_struct *work)
1733 {
1734         struct smc_link *link = container_of(work, struct smc_link,
1735                                              link_down_wrk);
1736         struct smc_link_group *lgr = link->lgr;
1737
1738         if (list_empty(&lgr->list))
1739                 return;
1740         wake_up_all(&lgr->llc_msg_waiter);
1741         mutex_lock(&lgr->llc_conf_mutex);
1742         smcr_link_down(link);
1743         mutex_unlock(&lgr->llc_conf_mutex);
1744 }
1745
1746 static int smc_vlan_by_tcpsk_walk(struct net_device *lower_dev,
1747                                   struct netdev_nested_priv *priv)
1748 {
1749         unsigned short *vlan_id = (unsigned short *)priv->data;
1750
1751         if (is_vlan_dev(lower_dev)) {
1752                 *vlan_id = vlan_dev_vlan_id(lower_dev);
1753                 return 1;
1754         }
1755
1756         return 0;
1757 }
1758
1759 /* Determine vlan of internal TCP socket. */
1760 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
1761 {
1762         struct dst_entry *dst = sk_dst_get(clcsock->sk);
1763         struct netdev_nested_priv priv;
1764         struct net_device *ndev;
1765         int rc = 0;
1766
1767         ini->vlan_id = 0;
1768         if (!dst) {
1769                 rc = -ENOTCONN;
1770                 goto out;
1771         }
1772         if (!dst->dev) {
1773                 rc = -ENODEV;
1774                 goto out_rel;
1775         }
1776
1777         ndev = dst->dev;
1778         if (is_vlan_dev(ndev)) {
1779                 ini->vlan_id = vlan_dev_vlan_id(ndev);
1780                 goto out_rel;
1781         }
1782
1783         priv.data = (void *)&ini->vlan_id;
1784         rtnl_lock();
1785         netdev_walk_all_lower_dev(ndev, smc_vlan_by_tcpsk_walk, &priv);
1786         rtnl_unlock();
1787
1788 out_rel:
1789         dst_release(dst);
1790 out:
1791         return rc;
1792 }
1793
1794 static bool smcr_lgr_match(struct smc_link_group *lgr, u8 smcr_version,
1795                            u8 peer_systemid[],
1796                            u8 peer_gid[],
1797                            u8 peer_mac_v1[],
1798                            enum smc_lgr_role role, u32 clcqpn,
1799                            struct net *net)
1800 {
1801         struct smc_link *lnk;
1802         int i;
1803
1804         if (memcmp(lgr->peer_systemid, peer_systemid, SMC_SYSTEMID_LEN) ||
1805             lgr->role != role)
1806                 return false;
1807
1808         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1809                 lnk = &lgr->lnk[i];
1810
1811                 if (!smc_link_active(lnk))
1812                         continue;
1813                 /* use verbs API to check netns, instead of lgr->net */
1814                 if (!rdma_dev_access_netns(lnk->smcibdev->ibdev, net))
1815                         return false;
1816                 if ((lgr->role == SMC_SERV || lnk->peer_qpn == clcqpn) &&
1817                     !memcmp(lnk->peer_gid, peer_gid, SMC_GID_SIZE) &&
1818                     (smcr_version == SMC_V2 ||
1819                      !memcmp(lnk->peer_mac, peer_mac_v1, ETH_ALEN)))
1820                         return true;
1821         }
1822         return false;
1823 }
1824
1825 static bool smcd_lgr_match(struct smc_link_group *lgr,
1826                            struct smcd_dev *smcismdev, u64 peer_gid)
1827 {
1828         return lgr->peer_gid == peer_gid && lgr->smcd == smcismdev;
1829 }
1830
1831 /* create a new SMC connection (and a new link group if necessary) */
1832 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
1833 {
1834         struct smc_connection *conn = &smc->conn;
1835         struct net *net = sock_net(&smc->sk);
1836         struct list_head *lgr_list;
1837         struct smc_link_group *lgr;
1838         enum smc_lgr_role role;
1839         spinlock_t *lgr_lock;
1840         int rc = 0;
1841
1842         lgr_list = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_list :
1843                                   &smc_lgr_list.list;
1844         lgr_lock = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_lock :
1845                                   &smc_lgr_list.lock;
1846         ini->first_contact_local = 1;
1847         role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
1848         if (role == SMC_CLNT && ini->first_contact_peer)
1849                 /* create new link group as well */
1850                 goto create;
1851
1852         /* determine if an existing link group can be reused */
1853         spin_lock_bh(lgr_lock);
1854         list_for_each_entry(lgr, lgr_list, list) {
1855                 write_lock_bh(&lgr->conns_lock);
1856                 if ((ini->is_smcd ?
1857                      smcd_lgr_match(lgr, ini->ism_dev[ini->ism_selected],
1858                                     ini->ism_peer_gid[ini->ism_selected]) :
1859                      smcr_lgr_match(lgr, ini->smcr_version,
1860                                     ini->peer_systemid,
1861                                     ini->peer_gid, ini->peer_mac, role,
1862                                     ini->ib_clcqpn, net)) &&
1863                     !lgr->sync_err &&
1864                     (ini->smcd_version == SMC_V2 ||
1865                      lgr->vlan_id == ini->vlan_id) &&
1866                     (role == SMC_CLNT || ini->is_smcd ||
1867                      lgr->conns_num < SMC_RMBS_PER_LGR_MAX)) {
1868                         /* link group found */
1869                         ini->first_contact_local = 0;
1870                         conn->lgr = lgr;
1871                         rc = smc_lgr_register_conn(conn, false);
1872                         write_unlock_bh(&lgr->conns_lock);
1873                         if (!rc && delayed_work_pending(&lgr->free_work))
1874                                 cancel_delayed_work(&lgr->free_work);
1875                         break;
1876                 }
1877                 write_unlock_bh(&lgr->conns_lock);
1878         }
1879         spin_unlock_bh(lgr_lock);
1880         if (rc)
1881                 return rc;
1882
1883         if (role == SMC_CLNT && !ini->first_contact_peer &&
1884             ini->first_contact_local) {
1885                 /* Server reuses a link group, but Client wants to start
1886                  * a new one
1887                  * send out_of_sync decline, reason synchr. error
1888                  */
1889                 return SMC_CLC_DECL_SYNCERR;
1890         }
1891
1892 create:
1893         if (ini->first_contact_local) {
1894                 rc = smc_lgr_create(smc, ini);
1895                 if (rc)
1896                         goto out;
1897                 lgr = conn->lgr;
1898                 write_lock_bh(&lgr->conns_lock);
1899                 rc = smc_lgr_register_conn(conn, true);
1900                 write_unlock_bh(&lgr->conns_lock);
1901                 if (rc) {
1902                         smc_lgr_cleanup_early(lgr);
1903                         goto out;
1904                 }
1905         }
1906         smc_lgr_hold(conn->lgr); /* lgr_put in smc_conn_free() */
1907         if (!conn->lgr->is_smcd)
1908                 smcr_link_hold(conn->lnk); /* link_put in smc_conn_free() */
1909         conn->freed = 0;
1910         conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
1911         conn->local_tx_ctrl.len = SMC_WR_TX_SIZE;
1912         conn->urg_state = SMC_URG_READ;
1913         init_waitqueue_head(&conn->cdc_pend_tx_wq);
1914         INIT_WORK(&smc->conn.abort_work, smc_conn_abort_work);
1915         if (ini->is_smcd) {
1916                 conn->rx_off = sizeof(struct smcd_cdc_msg);
1917                 smcd_cdc_rx_init(conn); /* init tasklet for this conn */
1918         } else {
1919                 conn->rx_off = 0;
1920         }
1921 #ifndef KERNEL_HAS_ATOMIC64
1922         spin_lock_init(&conn->acurs_lock);
1923 #endif
1924
1925 out:
1926         return rc;
1927 }
1928
1929 #define SMCD_DMBE_SIZES         6 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */
1930 #define SMCR_RMBE_SIZES         5 /* 0 -> 16KB, 1 -> 32KB, .. 5 -> 512KB */
1931
1932 /* convert the RMB size into the compressed notation (minimum 16K, see
1933  * SMCD/R_DMBE_SIZES.
1934  * In contrast to plain ilog2, this rounds towards the next power of 2,
1935  * so the socket application gets at least its desired sndbuf / rcvbuf size.
1936  */
1937 static u8 smc_compress_bufsize(int size, bool is_smcd, bool is_rmb)
1938 {
1939         const unsigned int max_scat = SG_MAX_SINGLE_ALLOC * PAGE_SIZE;
1940         u8 compressed;
1941
1942         if (size <= SMC_BUF_MIN_SIZE)
1943                 return 0;
1944
1945         size = (size - 1) >> 14;  /* convert to 16K multiple */
1946         compressed = min_t(u8, ilog2(size) + 1,
1947                            is_smcd ? SMCD_DMBE_SIZES : SMCR_RMBE_SIZES);
1948
1949         if (!is_smcd && is_rmb)
1950                 /* RMBs are backed by & limited to max size of scatterlists */
1951                 compressed = min_t(u8, compressed, ilog2(max_scat >> 14));
1952
1953         return compressed;
1954 }
1955
1956 /* convert the RMB size from compressed notation into integer */
1957 int smc_uncompress_bufsize(u8 compressed)
1958 {
1959         u32 size;
1960
1961         size = 0x00000001 << (((int)compressed) + 14);
1962         return (int)size;
1963 }
1964
1965 /* try to reuse a sndbuf or rmb description slot for a certain
1966  * buffer size; if not available, return NULL
1967  */
1968 static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize,
1969                                              struct mutex *lock,
1970                                              struct list_head *buf_list)
1971 {
1972         struct smc_buf_desc *buf_slot;
1973
1974         mutex_lock(lock);
1975         list_for_each_entry(buf_slot, buf_list, list) {
1976                 if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
1977                         mutex_unlock(lock);
1978                         return buf_slot;
1979                 }
1980         }
1981         mutex_unlock(lock);
1982         return NULL;
1983 }
1984
1985 /* one of the conditions for announcing a receiver's current window size is
1986  * that it "results in a minimum increase in the window size of 10% of the
1987  * receive buffer space" [RFC7609]
1988  */
1989 static inline int smc_rmb_wnd_update_limit(int rmbe_size)
1990 {
1991         return min_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
1992 }
1993
1994 /* map an rmb buf to a link */
1995 static int smcr_buf_map_link(struct smc_buf_desc *buf_desc, bool is_rmb,
1996                              struct smc_link *lnk)
1997 {
1998         int rc;
1999
2000         if (buf_desc->is_map_ib[lnk->link_idx])
2001                 return 0;
2002
2003         rc = sg_alloc_table(&buf_desc->sgt[lnk->link_idx], 1, GFP_KERNEL);
2004         if (rc)
2005                 return rc;
2006         sg_set_buf(buf_desc->sgt[lnk->link_idx].sgl,
2007                    buf_desc->cpu_addr, buf_desc->len);
2008
2009         /* map sg table to DMA address */
2010         rc = smc_ib_buf_map_sg(lnk, buf_desc,
2011                                is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2012         /* SMC protocol depends on mapping to one DMA address only */
2013         if (rc != 1) {
2014                 rc = -EAGAIN;
2015                 goto free_table;
2016         }
2017
2018         /* create a new memory region for the RMB */
2019         if (is_rmb) {
2020                 rc = smc_ib_get_memory_region(lnk->roce_pd,
2021                                               IB_ACCESS_REMOTE_WRITE |
2022                                               IB_ACCESS_LOCAL_WRITE,
2023                                               buf_desc, lnk->link_idx);
2024                 if (rc)
2025                         goto buf_unmap;
2026                 smc_ib_sync_sg_for_device(lnk, buf_desc, DMA_FROM_DEVICE);
2027         }
2028         buf_desc->is_map_ib[lnk->link_idx] = true;
2029         return 0;
2030
2031 buf_unmap:
2032         smc_ib_buf_unmap_sg(lnk, buf_desc,
2033                             is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2034 free_table:
2035         sg_free_table(&buf_desc->sgt[lnk->link_idx]);
2036         return rc;
2037 }
2038
2039 /* register a new rmb on IB device,
2040  * must be called under lgr->llc_conf_mutex lock
2041  */
2042 int smcr_link_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc)
2043 {
2044         if (list_empty(&link->lgr->list))
2045                 return -ENOLINK;
2046         if (!rmb_desc->is_reg_mr[link->link_idx]) {
2047                 /* register memory region for new rmb */
2048                 if (smc_wr_reg_send(link, rmb_desc->mr_rx[link->link_idx])) {
2049                         rmb_desc->is_reg_err = true;
2050                         return -EFAULT;
2051                 }
2052                 rmb_desc->is_reg_mr[link->link_idx] = true;
2053         }
2054         return 0;
2055 }
2056
2057 static int _smcr_buf_map_lgr(struct smc_link *lnk, struct mutex *lock,
2058                              struct list_head *lst, bool is_rmb)
2059 {
2060         struct smc_buf_desc *buf_desc, *bf;
2061         int rc = 0;
2062
2063         mutex_lock(lock);
2064         list_for_each_entry_safe(buf_desc, bf, lst, list) {
2065                 if (!buf_desc->used)
2066                         continue;
2067                 rc = smcr_buf_map_link(buf_desc, is_rmb, lnk);
2068                 if (rc)
2069                         goto out;
2070         }
2071 out:
2072         mutex_unlock(lock);
2073         return rc;
2074 }
2075
2076 /* map all used buffers of lgr for a new link */
2077 int smcr_buf_map_lgr(struct smc_link *lnk)
2078 {
2079         struct smc_link_group *lgr = lnk->lgr;
2080         int i, rc = 0;
2081
2082         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2083                 rc = _smcr_buf_map_lgr(lnk, &lgr->rmbs_lock,
2084                                        &lgr->rmbs[i], true);
2085                 if (rc)
2086                         return rc;
2087                 rc = _smcr_buf_map_lgr(lnk, &lgr->sndbufs_lock,
2088                                        &lgr->sndbufs[i], false);
2089                 if (rc)
2090                         return rc;
2091         }
2092         return 0;
2093 }
2094
2095 /* register all used buffers of lgr for a new link,
2096  * must be called under lgr->llc_conf_mutex lock
2097  */
2098 int smcr_buf_reg_lgr(struct smc_link *lnk)
2099 {
2100         struct smc_link_group *lgr = lnk->lgr;
2101         struct smc_buf_desc *buf_desc, *bf;
2102         int i, rc = 0;
2103
2104         mutex_lock(&lgr->rmbs_lock);
2105         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2106                 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list) {
2107                         if (!buf_desc->used)
2108                                 continue;
2109                         rc = smcr_link_reg_rmb(lnk, buf_desc);
2110                         if (rc)
2111                                 goto out;
2112                 }
2113         }
2114 out:
2115         mutex_unlock(&lgr->rmbs_lock);
2116         return rc;
2117 }
2118
2119 static struct smc_buf_desc *smcr_new_buf_create(struct smc_link_group *lgr,
2120                                                 bool is_rmb, int bufsize)
2121 {
2122         struct smc_buf_desc *buf_desc;
2123
2124         /* try to alloc a new buffer */
2125         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
2126         if (!buf_desc)
2127                 return ERR_PTR(-ENOMEM);
2128
2129         buf_desc->order = get_order(bufsize);
2130         buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN |
2131                                       __GFP_NOMEMALLOC | __GFP_COMP |
2132                                       __GFP_NORETRY | __GFP_ZERO,
2133                                       buf_desc->order);
2134         if (!buf_desc->pages) {
2135                 kfree(buf_desc);
2136                 return ERR_PTR(-EAGAIN);
2137         }
2138         buf_desc->cpu_addr = (void *)page_address(buf_desc->pages);
2139         buf_desc->len = bufsize;
2140         return buf_desc;
2141 }
2142
2143 /* map buf_desc on all usable links,
2144  * unused buffers stay mapped as long as the link is up
2145  */
2146 static int smcr_buf_map_usable_links(struct smc_link_group *lgr,
2147                                      struct smc_buf_desc *buf_desc, bool is_rmb)
2148 {
2149         int i, rc = 0;
2150
2151         /* protect against parallel link reconfiguration */
2152         mutex_lock(&lgr->llc_conf_mutex);
2153         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2154                 struct smc_link *lnk = &lgr->lnk[i];
2155
2156                 if (!smc_link_usable(lnk))
2157                         continue;
2158                 if (smcr_buf_map_link(buf_desc, is_rmb, lnk)) {
2159                         rc = -ENOMEM;
2160                         goto out;
2161                 }
2162         }
2163 out:
2164         mutex_unlock(&lgr->llc_conf_mutex);
2165         return rc;
2166 }
2167
2168 static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr,
2169                                                 bool is_dmb, int bufsize)
2170 {
2171         struct smc_buf_desc *buf_desc;
2172         int rc;
2173
2174         /* try to alloc a new DMB */
2175         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
2176         if (!buf_desc)
2177                 return ERR_PTR(-ENOMEM);
2178         if (is_dmb) {
2179                 rc = smc_ism_register_dmb(lgr, bufsize, buf_desc);
2180                 if (rc) {
2181                         kfree(buf_desc);
2182                         if (rc == -ENOMEM)
2183                                 return ERR_PTR(-EAGAIN);
2184                         if (rc == -ENOSPC)
2185                                 return ERR_PTR(-ENOSPC);
2186                         return ERR_PTR(-EIO);
2187                 }
2188                 buf_desc->pages = virt_to_page(buf_desc->cpu_addr);
2189                 /* CDC header stored in buf. So, pretend it was smaller */
2190                 buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg);
2191         } else {
2192                 buf_desc->cpu_addr = kzalloc(bufsize, GFP_KERNEL |
2193                                              __GFP_NOWARN | __GFP_NORETRY |
2194                                              __GFP_NOMEMALLOC);
2195                 if (!buf_desc->cpu_addr) {
2196                         kfree(buf_desc);
2197                         return ERR_PTR(-EAGAIN);
2198                 }
2199                 buf_desc->len = bufsize;
2200         }
2201         return buf_desc;
2202 }
2203
2204 static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb)
2205 {
2206         struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM);
2207         struct smc_connection *conn = &smc->conn;
2208         struct smc_link_group *lgr = conn->lgr;
2209         struct list_head *buf_list;
2210         int bufsize, bufsize_short;
2211         bool is_dgraded = false;
2212         struct mutex *lock;     /* lock buffer list */
2213         int sk_buf_size;
2214
2215         if (is_rmb)
2216                 /* use socket recv buffer size (w/o overhead) as start value */
2217                 sk_buf_size = smc->sk.sk_rcvbuf / 2;
2218         else
2219                 /* use socket send buffer size (w/o overhead) as start value */
2220                 sk_buf_size = smc->sk.sk_sndbuf / 2;
2221
2222         for (bufsize_short = smc_compress_bufsize(sk_buf_size, is_smcd, is_rmb);
2223              bufsize_short >= 0; bufsize_short--) {
2224                 if (is_rmb) {
2225                         lock = &lgr->rmbs_lock;
2226                         buf_list = &lgr->rmbs[bufsize_short];
2227                 } else {
2228                         lock = &lgr->sndbufs_lock;
2229                         buf_list = &lgr->sndbufs[bufsize_short];
2230                 }
2231                 bufsize = smc_uncompress_bufsize(bufsize_short);
2232
2233                 /* check for reusable slot in the link group */
2234                 buf_desc = smc_buf_get_slot(bufsize_short, lock, buf_list);
2235                 if (buf_desc) {
2236                         SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
2237                         SMC_STAT_BUF_REUSE(smc, is_smcd, is_rmb);
2238                         break; /* found reusable slot */
2239                 }
2240
2241                 if (is_smcd)
2242                         buf_desc = smcd_new_buf_create(lgr, is_rmb, bufsize);
2243                 else
2244                         buf_desc = smcr_new_buf_create(lgr, is_rmb, bufsize);
2245
2246                 if (PTR_ERR(buf_desc) == -ENOMEM)
2247                         break;
2248                 if (IS_ERR(buf_desc)) {
2249                         if (!is_dgraded) {
2250                                 is_dgraded = true;
2251                                 SMC_STAT_RMB_DOWNGRADED(smc, is_smcd, is_rmb);
2252                         }
2253                         continue;
2254                 }
2255
2256                 SMC_STAT_RMB_ALLOC(smc, is_smcd, is_rmb);
2257                 SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
2258                 buf_desc->used = 1;
2259                 mutex_lock(lock);
2260                 list_add(&buf_desc->list, buf_list);
2261                 mutex_unlock(lock);
2262                 break; /* found */
2263         }
2264
2265         if (IS_ERR(buf_desc))
2266                 return PTR_ERR(buf_desc);
2267
2268         if (!is_smcd) {
2269                 if (smcr_buf_map_usable_links(lgr, buf_desc, is_rmb)) {
2270                         smcr_buf_unuse(buf_desc, lgr);
2271                         return -ENOMEM;
2272                 }
2273         }
2274
2275         if (is_rmb) {
2276                 conn->rmb_desc = buf_desc;
2277                 conn->rmbe_size_short = bufsize_short;
2278                 smc->sk.sk_rcvbuf = bufsize * 2;
2279                 atomic_set(&conn->bytes_to_rcv, 0);
2280                 conn->rmbe_update_limit =
2281                         smc_rmb_wnd_update_limit(buf_desc->len);
2282                 if (is_smcd)
2283                         smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */
2284         } else {
2285                 conn->sndbuf_desc = buf_desc;
2286                 smc->sk.sk_sndbuf = bufsize * 2;
2287                 atomic_set(&conn->sndbuf_space, bufsize);
2288         }
2289         return 0;
2290 }
2291
2292 void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn)
2293 {
2294         if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd ||
2295             !smc_link_active(conn->lnk))
2296                 return;
2297         smc_ib_sync_sg_for_cpu(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
2298 }
2299
2300 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
2301 {
2302         if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd ||
2303             !smc_link_active(conn->lnk))
2304                 return;
2305         smc_ib_sync_sg_for_device(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
2306 }
2307
2308 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
2309 {
2310         int i;
2311
2312         if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd)
2313                 return;
2314         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2315                 if (!smc_link_active(&conn->lgr->lnk[i]))
2316                         continue;
2317                 smc_ib_sync_sg_for_cpu(&conn->lgr->lnk[i], conn->rmb_desc,
2318                                        DMA_FROM_DEVICE);
2319         }
2320 }
2321
2322 void smc_rmb_sync_sg_for_device(struct smc_connection *conn)
2323 {
2324         int i;
2325
2326         if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd)
2327                 return;
2328         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2329                 if (!smc_link_active(&conn->lgr->lnk[i]))
2330                         continue;
2331                 smc_ib_sync_sg_for_device(&conn->lgr->lnk[i], conn->rmb_desc,
2332                                           DMA_FROM_DEVICE);
2333         }
2334 }
2335
2336 /* create the send and receive buffer for an SMC socket;
2337  * receive buffers are called RMBs;
2338  * (even though the SMC protocol allows more than one RMB-element per RMB,
2339  * the Linux implementation uses just one RMB-element per RMB, i.e. uses an
2340  * extra RMB for every connection in a link group
2341  */
2342 int smc_buf_create(struct smc_sock *smc, bool is_smcd)
2343 {
2344         int rc;
2345
2346         /* create send buffer */
2347         rc = __smc_buf_create(smc, is_smcd, false);
2348         if (rc)
2349                 return rc;
2350         /* create rmb */
2351         rc = __smc_buf_create(smc, is_smcd, true);
2352         if (rc) {
2353                 mutex_lock(&smc->conn.lgr->sndbufs_lock);
2354                 list_del(&smc->conn.sndbuf_desc->list);
2355                 mutex_unlock(&smc->conn.lgr->sndbufs_lock);
2356                 smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc);
2357                 smc->conn.sndbuf_desc = NULL;
2358         }
2359         return rc;
2360 }
2361
2362 static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
2363 {
2364         int i;
2365
2366         for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) {
2367                 if (!test_and_set_bit(i, lgr->rtokens_used_mask))
2368                         return i;
2369         }
2370         return -ENOSPC;
2371 }
2372
2373 static int smc_rtoken_find_by_link(struct smc_link_group *lgr, int lnk_idx,
2374                                    u32 rkey)
2375 {
2376         int i;
2377
2378         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2379                 if (test_bit(i, lgr->rtokens_used_mask) &&
2380                     lgr->rtokens[i][lnk_idx].rkey == rkey)
2381                         return i;
2382         }
2383         return -ENOENT;
2384 }
2385
2386 /* set rtoken for a new link to an existing rmb */
2387 void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
2388                     __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey)
2389 {
2390         int rtok_idx;
2391
2392         rtok_idx = smc_rtoken_find_by_link(lgr, link_idx, ntohl(nw_rkey_known));
2393         if (rtok_idx == -ENOENT)
2394                 return;
2395         lgr->rtokens[rtok_idx][link_idx_new].rkey = ntohl(nw_rkey);
2396         lgr->rtokens[rtok_idx][link_idx_new].dma_addr = be64_to_cpu(nw_vaddr);
2397 }
2398
2399 /* set rtoken for a new link whose link_id is given */
2400 void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
2401                      __be64 nw_vaddr, __be32 nw_rkey)
2402 {
2403         u64 dma_addr = be64_to_cpu(nw_vaddr);
2404         u32 rkey = ntohl(nw_rkey);
2405         bool found = false;
2406         int link_idx;
2407
2408         for (link_idx = 0; link_idx < SMC_LINKS_PER_LGR_MAX; link_idx++) {
2409                 if (lgr->lnk[link_idx].link_id == link_id) {
2410                         found = true;
2411                         break;
2412                 }
2413         }
2414         if (!found)
2415                 return;
2416         lgr->rtokens[rtok_idx][link_idx].rkey = rkey;
2417         lgr->rtokens[rtok_idx][link_idx].dma_addr = dma_addr;
2418 }
2419
2420 /* add a new rtoken from peer */
2421 int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey)
2422 {
2423         struct smc_link_group *lgr = smc_get_lgr(lnk);
2424         u64 dma_addr = be64_to_cpu(nw_vaddr);
2425         u32 rkey = ntohl(nw_rkey);
2426         int i;
2427
2428         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2429                 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2430                     lgr->rtokens[i][lnk->link_idx].dma_addr == dma_addr &&
2431                     test_bit(i, lgr->rtokens_used_mask)) {
2432                         /* already in list */
2433                         return i;
2434                 }
2435         }
2436         i = smc_rmb_reserve_rtoken_idx(lgr);
2437         if (i < 0)
2438                 return i;
2439         lgr->rtokens[i][lnk->link_idx].rkey = rkey;
2440         lgr->rtokens[i][lnk->link_idx].dma_addr = dma_addr;
2441         return i;
2442 }
2443
2444 /* delete an rtoken from all links */
2445 int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey)
2446 {
2447         struct smc_link_group *lgr = smc_get_lgr(lnk);
2448         u32 rkey = ntohl(nw_rkey);
2449         int i, j;
2450
2451         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2452                 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2453                     test_bit(i, lgr->rtokens_used_mask)) {
2454                         for (j = 0; j < SMC_LINKS_PER_LGR_MAX; j++) {
2455                                 lgr->rtokens[i][j].rkey = 0;
2456                                 lgr->rtokens[i][j].dma_addr = 0;
2457                         }
2458                         clear_bit(i, lgr->rtokens_used_mask);
2459                         return 0;
2460                 }
2461         }
2462         return -ENOENT;
2463 }
2464
2465 /* save rkey and dma_addr received from peer during clc handshake */
2466 int smc_rmb_rtoken_handling(struct smc_connection *conn,
2467                             struct smc_link *lnk,
2468                             struct smc_clc_msg_accept_confirm *clc)
2469 {
2470         conn->rtoken_idx = smc_rtoken_add(lnk, clc->r0.rmb_dma_addr,
2471                                           clc->r0.rmb_rkey);
2472         if (conn->rtoken_idx < 0)
2473                 return conn->rtoken_idx;
2474         return 0;
2475 }
2476
2477 static void smc_core_going_away(void)
2478 {
2479         struct smc_ib_device *smcibdev;
2480         struct smcd_dev *smcd;
2481
2482         mutex_lock(&smc_ib_devices.mutex);
2483         list_for_each_entry(smcibdev, &smc_ib_devices.list, list) {
2484                 int i;
2485
2486                 for (i = 0; i < SMC_MAX_PORTS; i++)
2487                         set_bit(i, smcibdev->ports_going_away);
2488         }
2489         mutex_unlock(&smc_ib_devices.mutex);
2490
2491         mutex_lock(&smcd_dev_list.mutex);
2492         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2493                 smcd->going_away = 1;
2494         }
2495         mutex_unlock(&smcd_dev_list.mutex);
2496 }
2497
2498 /* Clean up all SMC link groups */
2499 static void smc_lgrs_shutdown(void)
2500 {
2501         struct smcd_dev *smcd;
2502
2503         smc_core_going_away();
2504
2505         smc_smcr_terminate_all(NULL);
2506
2507         mutex_lock(&smcd_dev_list.mutex);
2508         list_for_each_entry(smcd, &smcd_dev_list.list, list)
2509                 smc_smcd_terminate_all(smcd);
2510         mutex_unlock(&smcd_dev_list.mutex);
2511 }
2512
2513 static int smc_core_reboot_event(struct notifier_block *this,
2514                                  unsigned long event, void *ptr)
2515 {
2516         smc_lgrs_shutdown();
2517         smc_ib_unregister_client();
2518         return 0;
2519 }
2520
2521 static struct notifier_block smc_reboot_notifier = {
2522         .notifier_call = smc_core_reboot_event,
2523 };
2524
2525 int __init smc_core_init(void)
2526 {
2527         return register_reboot_notifier(&smc_reboot_notifier);
2528 }
2529
2530 /* Called (from smc_exit) when module is removed */
2531 void smc_core_exit(void)
2532 {
2533         unregister_reboot_notifier(&smc_reboot_notifier);
2534         smc_lgrs_shutdown();
2535 }