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 <[email protected]>
  10  */
  11
  12 #include <linux/socket.h>
  13 #include <linux/if_vlan.h>
  14 #include <linux/random.h>
  15 #include <linux/workqueue.h>
  16 #include <linux/wait.h>
  17 #include <linux/reboot.h>
  18 #include <linux/mutex.h>
  19 #include <linux/list.h>
  20 #include <linux/smc.h>
  21 #include <net/tcp.h>
  22 #include <net/sock.h>
  23 #include <rdma/ib_verbs.h>
  24 #include <rdma/ib_cache.h>
  25
  26 #include "smc.h"
  27 #include "smc_clc.h"
  28 #include "smc_core.h"
  29 #include "smc_ib.h"
  30 #include "smc_wr.h"
  31 #include "smc_llc.h"
  32 #include "smc_cdc.h"
  33 #include "smc_close.h"
  34 #include "smc_ism.h"
  35 #include "smc_netlink.h"
  36 #include "smc_stats.h"
  37 #include "smc_tracepoint.h"
  38
  39 #define SMC_LGR_NUM_INCR                256
  40 #define SMC_LGR_FREE_DELAY_SERV         (600 * HZ)
  41 #define SMC_LGR_FREE_DELAY_CLNT         (SMC_LGR_FREE_DELAY_SERV + 10 * HZ)
  42
  43 struct smc_lgr_list smc_lgr_list = {    /* established link groups */
  44         .lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
  45         .list = LIST_HEAD_INIT(smc_lgr_list.list),
  46         .num = 0,
  47 };
  48
  49 static atomic_t lgr_cnt = ATOMIC_INIT(0); /* number of existing link groups */
  50 static DECLARE_WAIT_QUEUE_HEAD(lgrs_deleted);
  51
  52 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
  53                          struct smc_buf_desc *buf_desc);
  54 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft);
  55
  56 static void smc_link_down_work(struct work_struct *work);
  57
  58 /* return head of link group list and its lock for a given link group */
  59 static inline struct list_head *smc_lgr_list_head(struct smc_link_group *lgr,
  60                                                   spinlock_t **lgr_lock)
  61 {
  62         if (lgr->is_smcd) {
  63                 *lgr_lock = &lgr->smcd->lgr_lock;
  64                 return &lgr->smcd->lgr_list;
  65         }
  66
  67         *lgr_lock = &smc_lgr_list.lock;
  68         return &smc_lgr_list.list;
  69 }
  70
  71 static void smc_ibdev_cnt_inc(struct smc_link *lnk)
  72 {
  73         atomic_inc(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
  74 }
  75
  76 static void smc_ibdev_cnt_dec(struct smc_link *lnk)
  77 {
  78         atomic_dec(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
  79 }
  80
  81 static void smc_lgr_schedule_free_work(struct smc_link_group *lgr)
  82 {
  83         /* client link group creation always follows the server link group
  84          * creation. For client use a somewhat higher removal delay time,
  85          * otherwise there is a risk of out-of-sync link groups.
  86          */
  87         if (!lgr->freeing) {
  88                 mod_delayed_work(system_wq, &lgr->free_work,
  89                                  (!lgr->is_smcd && lgr->role == SMC_CLNT) ?
  90                                                 SMC_LGR_FREE_DELAY_CLNT :
  91                                                 SMC_LGR_FREE_DELAY_SERV);
  92         }
  93 }
  94
  95 /* Register connection's alert token in our lookup structure.
  96  * To use rbtrees we have to implement our own insert core.
  97  * Requires @conns_lock
  98  * @smc         connection to register
  99  * Returns 0 on success, != otherwise.
 100  */
 101 static void smc_lgr_add_alert_token(struct smc_connection *conn)
 102 {
 103         struct rb_node **link, *parent = NULL;
 104         u32 token = conn->alert_token_local;
 105
 106         link = &conn->lgr->conns_all.rb_node;
 107         while (*link) {
 108                 struct smc_connection *cur = rb_entry(*link,
 109                                         struct smc_connection, alert_node);
 110
 111                 parent = *link;
 112                 if (cur->alert_token_local > token)
 113                         link = &parent->rb_left;
 114                 else
 115                         link = &parent->rb_right;
 116         }
 117         /* Put the new node there */
 118         rb_link_node(&conn->alert_node, parent, link);
 119         rb_insert_color(&conn->alert_node, &conn->lgr->conns_all);
 120 }
 121
 122 /* assign an SMC-R link to the connection */
 123 static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first)
 124 {
 125         enum smc_link_state expected = first ? SMC_LNK_ACTIVATING :
 126                                        SMC_LNK_ACTIVE;
 127         int i, j;
 128
 129         /* do link balancing */
 130         conn->lnk = NULL;       /* reset conn->lnk first */
 131         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 132                 struct smc_link *lnk = &conn->lgr->lnk[i];
 133
 134                 if (lnk->state != expected || lnk->link_is_asym)
 135                         continue;
 136                 if (conn->lgr->role == SMC_CLNT) {
 137                         conn->lnk = lnk; /* temporary, SMC server assigns link*/
 138                         break;
 139                 }
 140                 if (conn->lgr->conns_num % 2) {
 141                         for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) {
 142                                 struct smc_link *lnk2;
 143
 144                                 lnk2 = &conn->lgr->lnk[j];
 145                                 if (lnk2->state == expected &&
 146                                     !lnk2->link_is_asym) {
 147                                         conn->lnk = lnk2;
 148                                         break;
 149                                 }
 150                         }
 151                 }
 152                 if (!conn->lnk)
 153                         conn->lnk = lnk;
 154                 break;
 155         }
 156         if (!conn->lnk)
 157                 return SMC_CLC_DECL_NOACTLINK;
 158         atomic_inc(&conn->lnk->conn_cnt);
 159         return 0;
 160 }
 161
 162 /* Register connection in link group by assigning an alert token
 163  * registered in a search tree.
 164  * Requires @conns_lock
 165  * Note that '0' is a reserved value and not assigned.
 166  */
 167 static int smc_lgr_register_conn(struct smc_connection *conn, bool first)
 168 {
 169         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 170         static atomic_t nexttoken = ATOMIC_INIT(0);
 171         int rc;
 172
 173         if (!conn->lgr->is_smcd) {
 174                 rc = smcr_lgr_conn_assign_link(conn, first);
 175                 if (rc) {
 176                         conn->lgr = NULL;
 177                         return rc;
 178                 }
 179         }
 180         /* find a new alert_token_local value not yet used by some connection
 181          * in this link group
 182          */
 183         sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */
 184         while (!conn->alert_token_local) {
 185                 conn->alert_token_local = atomic_inc_return(&nexttoken);
 186                 if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr))
 187                         conn->alert_token_local = 0;
 188         }
 189         smc_lgr_add_alert_token(conn);
 190         conn->lgr->conns_num++;
 191         return 0;
 192 }
 193
 194 /* Unregister connection and reset the alert token of the given connection<
 195  */
 196 static void __smc_lgr_unregister_conn(struct smc_connection *conn)
 197 {
 198         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 199         struct smc_link_group *lgr = conn->lgr;
 200
 201         rb_erase(&conn->alert_node, &lgr->conns_all);
 202         if (conn->lnk)
 203                 atomic_dec(&conn->lnk->conn_cnt);
 204         lgr->conns_num--;
 205         conn->alert_token_local = 0;
 206         sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
 207 }
 208
 209 /* Unregister connection from lgr
 210  */
 211 static void smc_lgr_unregister_conn(struct smc_connection *conn)
 212 {
 213         struct smc_link_group *lgr = conn->lgr;
 214
 215         if (!smc_conn_lgr_valid(conn))
 216                 return;
 217         write_lock_bh(&lgr->conns_lock);
 218         if (conn->alert_token_local) {
 219                 __smc_lgr_unregister_conn(conn);
 220         }
 221         write_unlock_bh(&lgr->conns_lock);
 222 }
 223
 224 static void smc_lgr_buf_list_add(struct smc_link_group *lgr,
 225                                  bool is_rmb,
 226                                  struct list_head *buf_list,
 227                                  struct smc_buf_desc *buf_desc)
 228 {
 229         list_add(&buf_desc->list, buf_list);
 230         if (is_rmb) {
 231                 lgr->alloc_rmbs += buf_desc->len;
 232                 lgr->alloc_rmbs +=
 233                         lgr->is_smcd ? sizeof(struct smcd_cdc_msg) : 0;
 234         } else {
 235                 lgr->alloc_sndbufs += buf_desc->len;
 236         }
 237 }
 238
 239 static void smc_lgr_buf_list_del(struct smc_link_group *lgr,
 240                                  bool is_rmb,
 241                                  struct smc_buf_desc *buf_desc)
 242 {
 243         list_del(&buf_desc->list);
 244         if (is_rmb) {
 245                 lgr->alloc_rmbs -= buf_desc->len;
 246                 lgr->alloc_rmbs -=
 247                         lgr->is_smcd ? sizeof(struct smcd_cdc_msg) : 0;
 248         } else {
 249                 lgr->alloc_sndbufs -= buf_desc->len;
 250         }
 251 }
 252
 253 int smc_nl_get_sys_info(struct sk_buff *skb, struct netlink_callback *cb)
 254 {
 255         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 256         char hostname[SMC_MAX_HOSTNAME_LEN + 1];
 257         char smc_seid[SMC_MAX_EID_LEN + 1];
 258         struct nlattr *attrs;
 259         u8 *seid = NULL;
 260         u8 *host = NULL;
 261         void *nlh;
 262
 263         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 264                           &smc_gen_nl_family, NLM_F_MULTI,
 265                           SMC_NETLINK_GET_SYS_INFO);
 266         if (!nlh)
 267                 goto errmsg;
 268         if (cb_ctx->pos[0])
 269                 goto errout;
 270         attrs = nla_nest_start(skb, SMC_GEN_SYS_INFO);
 271         if (!attrs)
 272                 goto errout;
 273         if (nla_put_u8(skb, SMC_NLA_SYS_VER, SMC_V2))
 274                 goto errattr;
 275         if (nla_put_u8(skb, SMC_NLA_SYS_REL, SMC_RELEASE))
 276                 goto errattr;
 277         if (nla_put_u8(skb, SMC_NLA_SYS_IS_ISM_V2, smc_ism_is_v2_capable()))
 278                 goto errattr;
 279         if (nla_put_u8(skb, SMC_NLA_SYS_IS_SMCR_V2, true))
 280                 goto errattr;
 281         smc_clc_get_hostname(&host);
 282         if (host) {
 283                 memcpy(hostname, host, SMC_MAX_HOSTNAME_LEN);
 284                 hostname[SMC_MAX_HOSTNAME_LEN] = 0;
 285                 if (nla_put_string(skb, SMC_NLA_SYS_LOCAL_HOST, hostname))
 286                         goto errattr;
 287         }
 288         if (smc_ism_is_v2_capable()) {
 289                 smc_ism_get_system_eid(&seid);
 290                 memcpy(smc_seid, seid, SMC_MAX_EID_LEN);
 291                 smc_seid[SMC_MAX_EID_LEN] = 0;
 292                 if (nla_put_string(skb, SMC_NLA_SYS_SEID, smc_seid))
 293                         goto errattr;
 294         }
 295         nla_nest_end(skb, attrs);
 296         genlmsg_end(skb, nlh);
 297         cb_ctx->pos[0] = 1;
 298         return skb->len;
 299
 300 errattr:
 301         nla_nest_cancel(skb, attrs);
 302 errout:
 303         genlmsg_cancel(skb, nlh);
 304 errmsg:
 305         return skb->len;
 306 }
 307
 308 /* Fill SMC_NLA_LGR_D_V2_COMMON/SMC_NLA_LGR_R_V2_COMMON nested attributes */
 309 static int smc_nl_fill_lgr_v2_common(struct smc_link_group *lgr,
 310                                      struct sk_buff *skb,
 311                                      struct netlink_callback *cb,
 312                                      struct nlattr *v2_attrs)
 313 {
 314         char smc_host[SMC_MAX_HOSTNAME_LEN + 1];
 315         char smc_eid[SMC_MAX_EID_LEN + 1];
 316
 317         if (nla_put_u8(skb, SMC_NLA_LGR_V2_VER, lgr->smc_version))
 318                 goto errv2attr;
 319         if (nla_put_u8(skb, SMC_NLA_LGR_V2_REL, lgr->peer_smc_release))
 320                 goto errv2attr;
 321         if (nla_put_u8(skb, SMC_NLA_LGR_V2_OS, lgr->peer_os))
 322                 goto errv2attr;
 323         memcpy(smc_host, lgr->peer_hostname, SMC_MAX_HOSTNAME_LEN);
 324         smc_host[SMC_MAX_HOSTNAME_LEN] = 0;
 325         if (nla_put_string(skb, SMC_NLA_LGR_V2_PEER_HOST, smc_host))
 326                 goto errv2attr;
 327         memcpy(smc_eid, lgr->negotiated_eid, SMC_MAX_EID_LEN);
 328         smc_eid[SMC_MAX_EID_LEN] = 0;
 329         if (nla_put_string(skb, SMC_NLA_LGR_V2_NEG_EID, smc_eid))
 330                 goto errv2attr;
 331
 332         nla_nest_end(skb, v2_attrs);
 333         return 0;
 334
 335 errv2attr:
 336         nla_nest_cancel(skb, v2_attrs);
 337         return -EMSGSIZE;
 338 }
 339
 340 static int smc_nl_fill_smcr_lgr_v2(struct smc_link_group *lgr,
 341                                    struct sk_buff *skb,
 342                                    struct netlink_callback *cb)
 343 {
 344         struct nlattr *v2_attrs;
 345
 346         v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2);
 347         if (!v2_attrs)
 348                 goto errattr;
 349         if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_DIRECT, !lgr->uses_gateway))
 350                 goto errv2attr;
 351         if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_MAX_CONNS, lgr->max_conns))
 352                 goto errv2attr;
 353         if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_MAX_LINKS, lgr->max_links))
 354                 goto errv2attr;
 355
 356         nla_nest_end(skb, v2_attrs);
 357         return 0;
 358
 359 errv2attr:
 360         nla_nest_cancel(skb, v2_attrs);
 361 errattr:
 362         return -EMSGSIZE;
 363 }
 364
 365 static int smc_nl_fill_lgr(struct smc_link_group *lgr,
 366                            struct sk_buff *skb,
 367                            struct netlink_callback *cb)
 368 {
 369         char smc_target[SMC_MAX_PNETID_LEN + 1];
 370         struct nlattr *attrs, *v2_attrs;
 371
 372         attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCR);
 373         if (!attrs)
 374                 goto errout;
 375
 376         if (nla_put_u32(skb, SMC_NLA_LGR_R_ID, *((u32 *)&lgr->id)))
 377                 goto errattr;
 378         if (nla_put_u32(skb, SMC_NLA_LGR_R_CONNS_NUM, lgr->conns_num))
 379                 goto errattr;
 380         if (nla_put_u8(skb, SMC_NLA_LGR_R_ROLE, lgr->role))
 381                 goto errattr;
 382         if (nla_put_u8(skb, SMC_NLA_LGR_R_TYPE, lgr->type))
 383                 goto errattr;
 384         if (nla_put_u8(skb, SMC_NLA_LGR_R_BUF_TYPE, lgr->buf_type))
 385                 goto errattr;
 386         if (nla_put_u8(skb, SMC_NLA_LGR_R_VLAN_ID, lgr->vlan_id))
 387                 goto errattr;
 388         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_R_NET_COOKIE,
 389                               lgr->net->net_cookie, SMC_NLA_LGR_R_PAD))
 390                 goto errattr;
 391         memcpy(smc_target, lgr->pnet_id, SMC_MAX_PNETID_LEN);
 392         smc_target[SMC_MAX_PNETID_LEN] = 0;
 393         if (nla_put_string(skb, SMC_NLA_LGR_R_PNETID, smc_target))
 394                 goto errattr;
 395         if (nla_put_uint(skb, SMC_NLA_LGR_R_SNDBUF_ALLOC, lgr->alloc_sndbufs))
 396                 goto errattr;
 397         if (nla_put_uint(skb, SMC_NLA_LGR_R_RMB_ALLOC, lgr->alloc_rmbs))
 398                 goto errattr;
 399         if (lgr->smc_version > SMC_V1) {
 400                 v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2_COMMON);
 401                 if (!v2_attrs)
 402                         goto errattr;
 403                 if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
 404                         goto errattr;
 405                 if (smc_nl_fill_smcr_lgr_v2(lgr, skb, cb))
 406                         goto errattr;
 407         }
 408
 409         nla_nest_end(skb, attrs);
 410         return 0;
 411 errattr:
 412         nla_nest_cancel(skb, attrs);
 413 errout:
 414         return -EMSGSIZE;
 415 }
 416
 417 static int smc_nl_fill_lgr_link(struct smc_link_group *lgr,
 418                                 struct smc_link *link,
 419                                 struct sk_buff *skb,
 420                                 struct netlink_callback *cb)
 421 {
 422         char smc_ibname[IB_DEVICE_NAME_MAX];
 423         u8 smc_gid_target[41];
 424         struct nlattr *attrs;
 425         u32 link_uid = 0;
 426         void *nlh;
 427
 428         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 429                           &smc_gen_nl_family, NLM_F_MULTI,
 430                           SMC_NETLINK_GET_LINK_SMCR);
 431         if (!nlh)
 432                 goto errmsg;
 433
 434         attrs = nla_nest_start(skb, SMC_GEN_LINK_SMCR);
 435         if (!attrs)
 436                 goto errout;
 437
 438         if (nla_put_u8(skb, SMC_NLA_LINK_ID, link->link_id))
 439                 goto errattr;
 440         if (nla_put_u32(skb, SMC_NLA_LINK_STATE, link->state))
 441                 goto errattr;
 442         if (nla_put_u32(skb, SMC_NLA_LINK_CONN_CNT,
 443                         atomic_read(&link->conn_cnt)))
 444                 goto errattr;
 445         if (nla_put_u8(skb, SMC_NLA_LINK_IB_PORT, link->ibport))
 446                 goto errattr;
 447         if (nla_put_u32(skb, SMC_NLA_LINK_NET_DEV, link->ndev_ifidx))
 448                 goto errattr;
 449         snprintf(smc_ibname, sizeof(smc_ibname), "%s", link->ibname);
 450         if (nla_put_string(skb, SMC_NLA_LINK_IB_DEV, smc_ibname))
 451                 goto errattr;
 452         memcpy(&link_uid, link->link_uid, sizeof(link_uid));
 453         if (nla_put_u32(skb, SMC_NLA_LINK_UID, link_uid))
 454                 goto errattr;
 455         memcpy(&link_uid, link->peer_link_uid, sizeof(link_uid));
 456         if (nla_put_u32(skb, SMC_NLA_LINK_PEER_UID, link_uid))
 457                 goto errattr;
 458         memset(smc_gid_target, 0, sizeof(smc_gid_target));
 459         smc_gid_be16_convert(smc_gid_target, link->gid);
 460         if (nla_put_string(skb, SMC_NLA_LINK_GID, smc_gid_target))
 461                 goto errattr;
 462         memset(smc_gid_target, 0, sizeof(smc_gid_target));
 463         smc_gid_be16_convert(smc_gid_target, link->peer_gid);
 464         if (nla_put_string(skb, SMC_NLA_LINK_PEER_GID, smc_gid_target))
 465                 goto errattr;
 466
 467         nla_nest_end(skb, attrs);
 468         genlmsg_end(skb, nlh);
 469         return 0;
 470 errattr:
 471         nla_nest_cancel(skb, attrs);
 472 errout:
 473         genlmsg_cancel(skb, nlh);
 474 errmsg:
 475         return -EMSGSIZE;
 476 }
 477
 478 static int smc_nl_handle_lgr(struct smc_link_group *lgr,
 479                              struct sk_buff *skb,
 480                              struct netlink_callback *cb,
 481                              bool list_links)
 482 {
 483         void *nlh;
 484         int i;
 485
 486         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 487                           &smc_gen_nl_family, NLM_F_MULTI,
 488                           SMC_NETLINK_GET_LGR_SMCR);
 489         if (!nlh)
 490                 goto errmsg;
 491         if (smc_nl_fill_lgr(lgr, skb, cb))
 492                 goto errout;
 493
 494         genlmsg_end(skb, nlh);
 495         if (!list_links)
 496                 goto out;
 497         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 498                 if (!smc_link_usable(&lgr->lnk[i]))
 499                         continue;
 500                 if (smc_nl_fill_lgr_link(lgr, &lgr->lnk[i], skb, cb))
 501                         goto errout;
 502         }
 503 out:
 504         return 0;
 505
 506 errout:
 507         genlmsg_cancel(skb, nlh);
 508 errmsg:
 509         return -EMSGSIZE;
 510 }
 511
 512 static void smc_nl_fill_lgr_list(struct smc_lgr_list *smc_lgr,
 513                                  struct sk_buff *skb,
 514                                  struct netlink_callback *cb,
 515                                  bool list_links)
 516 {
 517         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 518         struct smc_link_group *lgr;
 519         int snum = cb_ctx->pos[0];
 520         int num = 0;
 521
 522         spin_lock_bh(&smc_lgr->lock);
 523         list_for_each_entry(lgr, &smc_lgr->list, list) {
 524                 if (num < snum)
 525                         goto next;
 526                 if (smc_nl_handle_lgr(lgr, skb, cb, list_links))
 527                         goto errout;
 528 next:
 529                 num++;
 530         }
 531 errout:
 532         spin_unlock_bh(&smc_lgr->lock);
 533         cb_ctx->pos[0] = num;
 534 }
 535
 536 static int smc_nl_fill_smcd_lgr(struct smc_link_group *lgr,
 537                                 struct sk_buff *skb,
 538                                 struct netlink_callback *cb)
 539 {
 540         char smc_pnet[SMC_MAX_PNETID_LEN + 1];
 541         struct smcd_dev *smcd = lgr->smcd;
 542         struct smcd_gid smcd_gid;
 543         struct nlattr *attrs;
 544         void *nlh;
 545
 546         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 547                           &smc_gen_nl_family, NLM_F_MULTI,
 548                           SMC_NETLINK_GET_LGR_SMCD);
 549         if (!nlh)
 550                 goto errmsg;
 551
 552         attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCD);
 553         if (!attrs)
 554                 goto errout;
 555
 556         if (nla_put_u32(skb, SMC_NLA_LGR_D_ID, *((u32 *)&lgr->id)))
 557                 goto errattr;
 558         smcd->ops->get_local_gid(smcd, &smcd_gid);
 559         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_GID,
 560                               smcd_gid.gid, SMC_NLA_LGR_D_PAD))
 561                 goto errattr;
 562         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_EXT_GID,
 563                               smcd_gid.gid_ext, SMC_NLA_LGR_D_PAD))
 564                 goto errattr;
 565         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_GID, lgr->peer_gid.gid,
 566                               SMC_NLA_LGR_D_PAD))
 567                 goto errattr;
 568         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_EXT_GID,
 569                               lgr->peer_gid.gid_ext, SMC_NLA_LGR_D_PAD))
 570                 goto errattr;
 571         if (nla_put_u8(skb, SMC_NLA_LGR_D_VLAN_ID, lgr->vlan_id))
 572                 goto errattr;
 573         if (nla_put_u32(skb, SMC_NLA_LGR_D_CONNS_NUM, lgr->conns_num))
 574                 goto errattr;
 575         if (nla_put_u32(skb, SMC_NLA_LGR_D_CHID, smc_ism_get_chid(lgr->smcd)))
 576                 goto errattr;
 577         if (nla_put_uint(skb, SMC_NLA_LGR_D_SNDBUF_ALLOC, lgr->alloc_sndbufs))
 578                 goto errattr;
 579         if (nla_put_uint(skb, SMC_NLA_LGR_D_DMB_ALLOC, lgr->alloc_rmbs))
 580                 goto errattr;
 581         memcpy(smc_pnet, lgr->smcd->pnetid, SMC_MAX_PNETID_LEN);
 582         smc_pnet[SMC_MAX_PNETID_LEN] = 0;
 583         if (nla_put_string(skb, SMC_NLA_LGR_D_PNETID, smc_pnet))
 584                 goto errattr;
 585         if (lgr->smc_version > SMC_V1) {
 586                 struct nlattr *v2_attrs;
 587
 588                 v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_D_V2_COMMON);
 589                 if (!v2_attrs)
 590                         goto errattr;
 591                 if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
 592                         goto errattr;
 593         }
 594         nla_nest_end(skb, attrs);
 595         genlmsg_end(skb, nlh);
 596         return 0;
 597
 598 errattr:
 599         nla_nest_cancel(skb, attrs);
 600 errout:
 601         genlmsg_cancel(skb, nlh);
 602 errmsg:
 603         return -EMSGSIZE;
 604 }
 605
 606 static int smc_nl_handle_smcd_lgr(struct smcd_dev *dev,
 607                                   struct sk_buff *skb,
 608                                   struct netlink_callback *cb)
 609 {
 610         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 611         struct smc_link_group *lgr;
 612         int snum = cb_ctx->pos[1];
 613         int rc = 0, num = 0;
 614
 615         spin_lock_bh(&dev->lgr_lock);
 616         list_for_each_entry(lgr, &dev->lgr_list, list) {
 617                 if (!lgr->is_smcd)
 618                         continue;
 619                 if (num < snum)
 620                         goto next;
 621                 rc = smc_nl_fill_smcd_lgr(lgr, skb, cb);
 622                 if (rc)
 623                         goto errout;
 624 next:
 625                 num++;
 626         }
 627 errout:
 628         spin_unlock_bh(&dev->lgr_lock);
 629         cb_ctx->pos[1] = num;
 630         return rc;
 631 }
 632
 633 static int smc_nl_fill_smcd_dev(struct smcd_dev_list *dev_list,
 634                                 struct sk_buff *skb,
 635                                 struct netlink_callback *cb)
 636 {
 637         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 638         struct smcd_dev *smcd_dev;
 639         int snum = cb_ctx->pos[0];
 640         int rc = 0, num = 0;
 641
 642         mutex_lock(&dev_list->mutex);
 643         list_for_each_entry(smcd_dev, &dev_list->list, list) {
 644                 if (list_empty(&smcd_dev->lgr_list))
 645                         continue;
 646                 if (num < snum)
 647                         goto next;
 648                 rc = smc_nl_handle_smcd_lgr(smcd_dev, skb, cb);
 649                 if (rc)
 650                         goto errout;
 651 next:
 652                 num++;
 653         }
 654 errout:
 655         mutex_unlock(&dev_list->mutex);
 656         cb_ctx->pos[0] = num;
 657         return rc;
 658 }
 659
 660 int smcr_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
 661 {
 662         bool list_links = false;
 663
 664         smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
 665         return skb->len;
 666 }
 667
 668 int smcr_nl_get_link(struct sk_buff *skb, struct netlink_callback *cb)
 669 {
 670         bool list_links = true;
 671
 672         smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
 673         return skb->len;
 674 }
 675
 676 int smcd_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
 677 {
 678         smc_nl_fill_smcd_dev(&smcd_dev_list, skb, cb);
 679         return skb->len;
 680 }
 681
 682 void smc_lgr_cleanup_early(struct smc_link_group *lgr)
 683 {
 684         spinlock_t *lgr_lock;
 685
 686         if (!lgr)
 687                 return;
 688
 689         smc_lgr_list_head(lgr, &lgr_lock);
 690         spin_lock_bh(lgr_lock);
 691         /* do not use this link group for new connections */
 692         if (!list_empty(&lgr->list))
 693                 list_del_init(&lgr->list);
 694         spin_unlock_bh(lgr_lock);
 695         __smc_lgr_terminate(lgr, true);
 696 }
 697
 698 static void smcr_lgr_link_deactivate_all(struct smc_link_group *lgr)
 699 {
 700         int i;
 701
 702         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 703                 struct smc_link *lnk = &lgr->lnk[i];
 704
 705                 if (smc_link_sendable(lnk))
 706                         lnk->state = SMC_LNK_INACTIVE;
 707         }
 708         wake_up_all(&lgr->llc_msg_waiter);
 709         wake_up_all(&lgr->llc_flow_waiter);
 710 }
 711
 712 static void smc_lgr_free(struct smc_link_group *lgr);
 713
 714 static void smc_lgr_free_work(struct work_struct *work)
 715 {
 716         struct smc_link_group *lgr = container_of(to_delayed_work(work),
 717                                                   struct smc_link_group,
 718                                                   free_work);
 719         spinlock_t *lgr_lock;
 720         bool conns;
 721
 722         smc_lgr_list_head(lgr, &lgr_lock);
 723         spin_lock_bh(lgr_lock);
 724         if (lgr->freeing) {
 725                 spin_unlock_bh(lgr_lock);
 726                 return;
 727         }
 728         read_lock_bh(&lgr->conns_lock);
 729         conns = RB_EMPTY_ROOT(&lgr->conns_all);
 730         read_unlock_bh(&lgr->conns_lock);
 731         if (!conns) { /* number of lgr connections is no longer zero */
 732                 spin_unlock_bh(lgr_lock);
 733                 return;
 734         }
 735         list_del_init(&lgr->list); /* remove from smc_lgr_list */
 736         lgr->freeing = 1; /* this instance does the freeing, no new schedule */
 737         spin_unlock_bh(lgr_lock);
 738         cancel_delayed_work(&lgr->free_work);
 739
 740         if (!lgr->is_smcd && !lgr->terminating)
 741                 smc_llc_send_link_delete_all(lgr, true,
 742                                              SMC_LLC_DEL_PROG_INIT_TERM);
 743         if (lgr->is_smcd && !lgr->terminating)
 744                 smc_ism_signal_shutdown(lgr);
 745         if (!lgr->is_smcd)
 746                 smcr_lgr_link_deactivate_all(lgr);
 747         smc_lgr_free(lgr);
 748 }
 749
 750 static void smc_lgr_terminate_work(struct work_struct *work)
 751 {
 752         struct smc_link_group *lgr = container_of(work, struct smc_link_group,
 753                                                   terminate_work);
 754
 755         __smc_lgr_terminate(lgr, true);
 756 }
 757
 758 /* return next unique link id for the lgr */
 759 static u8 smcr_next_link_id(struct smc_link_group *lgr)
 760 {
 761         u8 link_id;
 762         int i;
 763
 764         while (1) {
 765 again:
 766                 link_id = ++lgr->next_link_id;
 767                 if (!link_id)   /* skip zero as link_id */
 768                         link_id = ++lgr->next_link_id;
 769                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 770                         if (smc_link_usable(&lgr->lnk[i]) &&
 771                             lgr->lnk[i].link_id == link_id)
 772                                 goto again;
 773                 }
 774                 break;
 775         }
 776         return link_id;
 777 }
 778
 779 static void smcr_copy_dev_info_to_link(struct smc_link *link)
 780 {
 781         struct smc_ib_device *smcibdev = link->smcibdev;
 782
 783         snprintf(link->ibname, sizeof(link->ibname), "%s",
 784                  smcibdev->ibdev->name);
 785         link->ndev_ifidx = smcibdev->ndev_ifidx[link->ibport - 1];
 786 }
 787
 788 int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
 789                    u8 link_idx, struct smc_init_info *ini)
 790 {
 791         struct smc_ib_device *smcibdev;
 792         u8 rndvec[3];
 793         int rc;
 794
 795         if (lgr->smc_version == SMC_V2) {
 796                 lnk->smcibdev = ini->smcrv2.ib_dev_v2;
 797                 lnk->ibport = ini->smcrv2.ib_port_v2;
 798         } else {
 799                 lnk->smcibdev = ini->ib_dev;
 800                 lnk->ibport = ini->ib_port;
 801         }
 802         get_device(&lnk->smcibdev->ibdev->dev);
 803         atomic_inc(&lnk->smcibdev->lnk_cnt);
 804         refcount_set(&lnk->refcnt, 1); /* link refcnt is set to 1 */
 805         lnk->clearing = 0;
 806         lnk->path_mtu = lnk->smcibdev->pattr[lnk->ibport - 1].active_mtu;
 807         lnk->link_id = smcr_next_link_id(lgr);
 808         lnk->lgr = lgr;
 809         smc_lgr_hold(lgr); /* lgr_put in smcr_link_clear() */
 810         lnk->link_idx = link_idx;
 811         lnk->wr_rx_id_compl = 0;
 812         smc_ibdev_cnt_inc(lnk);
 813         smcr_copy_dev_info_to_link(lnk);
 814         atomic_set(&lnk->conn_cnt, 0);
 815         smc_llc_link_set_uid(lnk);
 816         INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
 817         if (!lnk->smcibdev->initialized) {
 818                 rc = (int)smc_ib_setup_per_ibdev(lnk->smcibdev);
 819                 if (rc)
 820                         goto out;
 821         }
 822         get_random_bytes(rndvec, sizeof(rndvec));
 823         lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) +
 824                 (rndvec[2] << 16);
 825         rc = smc_ib_determine_gid(lnk->smcibdev, lnk->ibport,
 826                                   ini->vlan_id, lnk->gid, &lnk->sgid_index,
 827                                   lgr->smc_version == SMC_V2 ?
 828                                                   &ini->smcrv2 : NULL);
 829         if (rc)
 830                 goto out;
 831         rc = smc_llc_link_init(lnk);
 832         if (rc)
 833                 goto out;
 834         rc = smc_wr_alloc_link_mem(lnk);
 835         if (rc)
 836                 goto clear_llc_lnk;
 837         rc = smc_ib_create_protection_domain(lnk);
 838         if (rc)
 839                 goto free_link_mem;
 840         rc = smc_ib_create_queue_pair(lnk);
 841         if (rc)
 842                 goto dealloc_pd;
 843         rc = smc_wr_create_link(lnk);
 844         if (rc)
 845                 goto destroy_qp;
 846         lnk->state = SMC_LNK_ACTIVATING;
 847         return 0;
 848
 849 destroy_qp:
 850         smc_ib_destroy_queue_pair(lnk);
 851 dealloc_pd:
 852         smc_ib_dealloc_protection_domain(lnk);
 853 free_link_mem:
 854         smc_wr_free_link_mem(lnk);
 855 clear_llc_lnk:
 856         smc_llc_link_clear(lnk, false);
 857 out:
 858         smc_ibdev_cnt_dec(lnk);
 859         put_device(&lnk->smcibdev->ibdev->dev);
 860         smcibdev = lnk->smcibdev;
 861         memset(lnk, 0, sizeof(struct smc_link));
 862         lnk->state = SMC_LNK_UNUSED;
 863         if (!atomic_dec_return(&smcibdev->lnk_cnt))
 864                 wake_up(&smcibdev->lnks_deleted);
 865         smc_lgr_put(lgr); /* lgr_hold above */
 866         return rc;
 867 }
 868
 869 /* create a new SMC link group */
 870 static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
 871 {
 872         struct smc_link_group *lgr;
 873         struct list_head *lgr_list;
 874         struct smcd_dev *smcd;
 875         struct smc_link *lnk;
 876         spinlock_t *lgr_lock;
 877         u8 link_idx;
 878         int rc = 0;
 879         int i;
 880
 881         if (ini->is_smcd && ini->vlan_id) {
 882                 if (smc_ism_get_vlan(ini->ism_dev[ini->ism_selected],
 883                                      ini->vlan_id)) {
 884                         rc = SMC_CLC_DECL_ISMVLANERR;
 885                         goto out;
 886                 }
 887         }
 888
 889         lgr = kzalloc(sizeof(*lgr), GFP_KERNEL);
 890         if (!lgr) {
 891                 rc = SMC_CLC_DECL_MEM;
 892                 goto ism_put_vlan;
 893         }
 894         lgr->tx_wq = alloc_workqueue("smc_tx_wq-%*phN", 0, 0,
 895                                      SMC_LGR_ID_SIZE, &lgr->id);
 896         if (!lgr->tx_wq) {
 897                 rc = -ENOMEM;
 898                 goto free_lgr;
 899         }
 900         lgr->is_smcd = ini->is_smcd;
 901         lgr->sync_err = 0;
 902         lgr->terminating = 0;
 903         lgr->freeing = 0;
 904         lgr->vlan_id = ini->vlan_id;
 905         refcount_set(&lgr->refcnt, 1); /* set lgr refcnt to 1 */
 906         init_rwsem(&lgr->sndbufs_lock);
 907         init_rwsem(&lgr->rmbs_lock);
 908         rwlock_init(&lgr->conns_lock);
 909         for (i = 0; i < SMC_RMBE_SIZES; i++) {
 910                 INIT_LIST_HEAD(&lgr->sndbufs[i]);
 911                 INIT_LIST_HEAD(&lgr->rmbs[i]);
 912         }
 913         lgr->next_link_id = 0;
 914         smc_lgr_list.num += SMC_LGR_NUM_INCR;
 915         memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE);
 916         INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
 917         INIT_WORK(&lgr->terminate_work, smc_lgr_terminate_work);
 918         lgr->conns_all = RB_ROOT;
 919         if (ini->is_smcd) {
 920                 /* SMC-D specific settings */
 921                 smcd = ini->ism_dev[ini->ism_selected];
 922                 get_device(smcd->ops->get_dev(smcd));
 923                 lgr->peer_gid.gid =
 924                         ini->ism_peer_gid[ini->ism_selected].gid;
 925                 lgr->peer_gid.gid_ext =
 926                         ini->ism_peer_gid[ini->ism_selected].gid_ext;
 927                 lgr->smcd = ini->ism_dev[ini->ism_selected];
 928                 lgr_list = &ini->ism_dev[ini->ism_selected]->lgr_list;
 929                 lgr_lock = &lgr->smcd->lgr_lock;
 930                 lgr->smc_version = ini->smcd_version;
 931                 lgr->peer_shutdown = 0;
 932                 atomic_inc(&ini->ism_dev[ini->ism_selected]->lgr_cnt);
 933         } else {
 934                 /* SMC-R specific settings */
 935                 struct smc_ib_device *ibdev;
 936                 int ibport;
 937
 938                 lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
 939                 lgr->smc_version = ini->smcr_version;
 940                 memcpy(lgr->peer_systemid, ini->peer_systemid,
 941                        SMC_SYSTEMID_LEN);
 942                 if (lgr->smc_version == SMC_V2) {
 943                         ibdev = ini->smcrv2.ib_dev_v2;
 944                         ibport = ini->smcrv2.ib_port_v2;
 945                         lgr->saddr = ini->smcrv2.saddr;
 946                         lgr->uses_gateway = ini->smcrv2.uses_gateway;
 947                         memcpy(lgr->nexthop_mac, ini->smcrv2.nexthop_mac,
 948                                ETH_ALEN);
 949                         lgr->max_conns = ini->max_conns;
 950                         lgr->max_links = ini->max_links;
 951                 } else {
 952                         ibdev = ini->ib_dev;
 953                         ibport = ini->ib_port;
 954                         lgr->max_conns = SMC_CONN_PER_LGR_MAX;
 955                         lgr->max_links = SMC_LINKS_ADD_LNK_MAX;
 956                 }
 957                 memcpy(lgr->pnet_id, ibdev->pnetid[ibport - 1],
 958                        SMC_MAX_PNETID_LEN);
 959                 rc = smc_wr_alloc_lgr_mem(lgr);
 960                 if (rc)
 961                         goto free_wq;
 962                 smc_llc_lgr_init(lgr, smc);
 963
 964                 link_idx = SMC_SINGLE_LINK;
 965                 lnk = &lgr->lnk[link_idx];
 966                 rc = smcr_link_init(lgr, lnk, link_idx, ini);
 967                 if (rc) {
 968                         smc_wr_free_lgr_mem(lgr);
 969                         goto free_wq;
 970                 }
 971                 lgr->net = smc_ib_net(lnk->smcibdev);
 972                 lgr_list = &smc_lgr_list.list;
 973                 lgr_lock = &smc_lgr_list.lock;
 974                 lgr->buf_type = lgr->net->smc.sysctl_smcr_buf_type;
 975                 atomic_inc(&lgr_cnt);
 976         }
 977         smc->conn.lgr = lgr;
 978         spin_lock_bh(lgr_lock);
 979         list_add_tail(&lgr->list, lgr_list);
 980         spin_unlock_bh(lgr_lock);
 981         return 0;
 982
 983 free_wq:
 984         destroy_workqueue(lgr->tx_wq);
 985 free_lgr:
 986         kfree(lgr);
 987 ism_put_vlan:
 988         if (ini->is_smcd && ini->vlan_id)
 989                 smc_ism_put_vlan(ini->ism_dev[ini->ism_selected], ini->vlan_id);
 990 out:
 991         if (rc < 0) {
 992                 if (rc == -ENOMEM)
 993                         rc = SMC_CLC_DECL_MEM;
 994                 else
 995                         rc = SMC_CLC_DECL_INTERR;
 996         }
 997         return rc;
 998 }
 999
1000 static int smc_write_space(struct smc_connection *conn)
1001 {
1002         int buffer_len = conn->peer_rmbe_size;
1003         union smc_host_cursor prod;
1004         union smc_host_cursor cons;
1005         int space;
1006
1007         smc_curs_copy(&prod, &conn->local_tx_ctrl.prod, conn);
1008         smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
1009         /* determine rx_buf space */
1010         space = buffer_len - smc_curs_diff(buffer_len, &cons, &prod);
1011         return space;
1012 }
1013
1014 static int smc_switch_cursor(struct smc_sock *smc, struct smc_cdc_tx_pend *pend,
1015                              struct smc_wr_buf *wr_buf)
1016 {
1017         struct smc_connection *conn = &smc->conn;
1018         union smc_host_cursor cons, fin;
1019         int rc = 0;
1020         int diff;
1021
1022         smc_curs_copy(&conn->tx_curs_sent, &conn->tx_curs_fin, conn);
1023         smc_curs_copy(&fin, &conn->local_tx_ctrl_fin, conn);
1024         /* set prod cursor to old state, enforce tx_rdma_writes() */
1025         smc_curs_copy(&conn->local_tx_ctrl.prod, &fin, conn);
1026         smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
1027
1028         if (smc_curs_comp(conn->peer_rmbe_size, &cons, &fin) < 0) {
1029                 /* cons cursor advanced more than fin, and prod was set
1030                  * fin above, so now prod is smaller than cons. Fix that.
1031                  */
1032                 diff = smc_curs_diff(conn->peer_rmbe_size, &fin, &cons);
1033                 smc_curs_add(conn->sndbuf_desc->len,
1034                              &conn->tx_curs_sent, diff);
1035                 smc_curs_add(conn->sndbuf_desc->len,
1036                              &conn->tx_curs_fin, diff);
1037
1038                 smp_mb__before_atomic();
1039                 atomic_add(diff, &conn->sndbuf_space);
1040                 smp_mb__after_atomic();
1041
1042                 smc_curs_add(conn->peer_rmbe_size,
1043                              &conn->local_tx_ctrl.prod, diff);
1044                 smc_curs_add(conn->peer_rmbe_size,
1045                              &conn->local_tx_ctrl_fin, diff);
1046         }
1047         /* recalculate, value is used by tx_rdma_writes() */
1048         atomic_set(&smc->conn.peer_rmbe_space, smc_write_space(conn));
1049
1050         if (smc->sk.sk_state != SMC_INIT &&
1051             smc->sk.sk_state != SMC_CLOSED) {
1052                 rc = smcr_cdc_msg_send_validation(conn, pend, wr_buf);
1053                 if (!rc) {
1054                         queue_delayed_work(conn->lgr->tx_wq, &conn->tx_work, 0);
1055                         smc->sk.sk_data_ready(&smc->sk);
1056                 }
1057         } else {
1058                 smc_wr_tx_put_slot(conn->lnk,
1059                                    (struct smc_wr_tx_pend_priv *)pend);
1060         }
1061         return rc;
1062 }
1063
1064 void smc_switch_link_and_count(struct smc_connection *conn,
1065                                struct smc_link *to_lnk)
1066 {
1067         atomic_dec(&conn->lnk->conn_cnt);
1068         /* link_hold in smc_conn_create() */
1069         smcr_link_put(conn->lnk);
1070         conn->lnk = to_lnk;
1071         atomic_inc(&conn->lnk->conn_cnt);
1072         /* link_put in smc_conn_free() */
1073         smcr_link_hold(conn->lnk);
1074 }
1075
1076 struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
1077                                   struct smc_link *from_lnk, bool is_dev_err)
1078 {
1079         struct smc_link *to_lnk = NULL;
1080         struct smc_cdc_tx_pend *pend;
1081         struct smc_connection *conn;
1082         struct smc_wr_buf *wr_buf;
1083         struct smc_sock *smc;
1084         struct rb_node *node;
1085         int i, rc = 0;
1086
1087         /* link is inactive, wake up tx waiters */
1088         smc_wr_wakeup_tx_wait(from_lnk);
1089
1090         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1091                 if (!smc_link_active(&lgr->lnk[i]) || i == from_lnk->link_idx)
1092                         continue;
1093                 if (is_dev_err && from_lnk->smcibdev == lgr->lnk[i].smcibdev &&
1094                     from_lnk->ibport == lgr->lnk[i].ibport) {
1095                         continue;
1096                 }
1097                 to_lnk = &lgr->lnk[i];
1098                 break;
1099         }
1100         if (!to_lnk || !smc_wr_tx_link_hold(to_lnk)) {
1101                 smc_lgr_terminate_sched(lgr);
1102                 return NULL;
1103         }
1104 again:
1105         read_lock_bh(&lgr->conns_lock);
1106         for (node = rb_first(&lgr->conns_all); node; node = rb_next(node)) {
1107                 conn = rb_entry(node, struct smc_connection, alert_node);
1108                 if (conn->lnk != from_lnk)
1109                         continue;
1110                 smc = container_of(conn, struct smc_sock, conn);
1111                 /* conn->lnk not yet set in SMC_INIT state */
1112                 if (smc->sk.sk_state == SMC_INIT)
1113                         continue;
1114                 if (smc->sk.sk_state == SMC_CLOSED ||
1115                     smc->sk.sk_state == SMC_PEERCLOSEWAIT1 ||
1116                     smc->sk.sk_state == SMC_PEERCLOSEWAIT2 ||
1117                     smc->sk.sk_state == SMC_APPFINCLOSEWAIT ||
1118                     smc->sk.sk_state == SMC_APPCLOSEWAIT1 ||
1119                     smc->sk.sk_state == SMC_APPCLOSEWAIT2 ||
1120                     smc->sk.sk_state == SMC_PEERFINCLOSEWAIT ||
1121                     smc->sk.sk_state == SMC_PEERABORTWAIT ||
1122                     smc->sk.sk_state == SMC_PROCESSABORT) {
1123                         spin_lock_bh(&conn->send_lock);
1124                         smc_switch_link_and_count(conn, to_lnk);
1125                         spin_unlock_bh(&conn->send_lock);
1126                         continue;
1127                 }
1128                 sock_hold(&smc->sk);
1129                 read_unlock_bh(&lgr->conns_lock);
1130                 /* pre-fetch buffer outside of send_lock, might sleep */
1131                 rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend);
1132                 if (rc)
1133                         goto err_out;
1134                 /* avoid race with smcr_tx_sndbuf_nonempty() */
1135                 spin_lock_bh(&conn->send_lock);
1136                 smc_switch_link_and_count(conn, to_lnk);
1137                 rc = smc_switch_cursor(smc, pend, wr_buf);
1138                 spin_unlock_bh(&conn->send_lock);
1139                 sock_put(&smc->sk);
1140                 if (rc)
1141                         goto err_out;
1142                 goto again;
1143         }
1144         read_unlock_bh(&lgr->conns_lock);
1145         smc_wr_tx_link_put(to_lnk);
1146         return to_lnk;
1147
1148 err_out:
1149         smcr_link_down_cond_sched(to_lnk);
1150         smc_wr_tx_link_put(to_lnk);
1151         return NULL;
1152 }
1153
1154 static void smcr_buf_unuse(struct smc_buf_desc *buf_desc, bool is_rmb,
1155                            struct smc_link_group *lgr)
1156 {
1157         struct rw_semaphore *lock;      /* lock buffer list */
1158         int rc;
1159
1160         if (is_rmb && buf_desc->is_conf_rkey && !list_empty(&lgr->list)) {
1161                 /* unregister rmb with peer */
1162                 rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
1163                 if (!rc) {
1164                         /* protect against smc_llc_cli_rkey_exchange() */
1165                         down_read(&lgr->llc_conf_mutex);
1166                         smc_llc_do_delete_rkey(lgr, buf_desc);
1167                         buf_desc->is_conf_rkey = false;
1168                         up_read(&lgr->llc_conf_mutex);
1169                         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
1170                 }
1171         }
1172
1173         if (buf_desc->is_reg_err) {
1174                 /* buf registration failed, reuse not possible */
1175                 lock = is_rmb ? &lgr->rmbs_lock :
1176                                 &lgr->sndbufs_lock;
1177                 down_write(lock);
1178                 smc_lgr_buf_list_del(lgr, is_rmb, buf_desc);
1179                 up_write(lock);
1180
1181                 smc_buf_free(lgr, is_rmb, buf_desc);
1182         } else {
1183                 /* memzero_explicit provides potential memory barrier semantics */
1184                 memzero_explicit(buf_desc->cpu_addr, buf_desc->len);
1185                 WRITE_ONCE(buf_desc->used, 0);
1186         }
1187 }
1188
1189 static void smcd_buf_detach(struct smc_connection *conn)
1190 {
1191         struct smcd_dev *smcd = conn->lgr->smcd;
1192         u64 peer_token = conn->peer_token;
1193
1194         if (!conn->sndbuf_desc)
1195                 return;
1196
1197         smc_ism_detach_dmb(smcd, peer_token);
1198
1199         kfree(conn->sndbuf_desc);
1200         conn->sndbuf_desc = NULL;
1201 }
1202
1203 static void smc_buf_unuse(struct smc_connection *conn,
1204                           struct smc_link_group *lgr)
1205 {
1206         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1207         bool is_smcd = lgr->is_smcd;
1208         int bufsize;
1209
1210         if (conn->sndbuf_desc) {
1211                 bufsize = conn->sndbuf_desc->len;
1212                 if (!is_smcd && conn->sndbuf_desc->is_vm) {
1213                         smcr_buf_unuse(conn->sndbuf_desc, false, lgr);
1214                 } else {
1215                         memzero_explicit(conn->sndbuf_desc->cpu_addr, bufsize);
1216                         WRITE_ONCE(conn->sndbuf_desc->used, 0);
1217                 }
1218                 SMC_STAT_RMB_SIZE(smc, is_smcd, false, false, bufsize);
1219         }
1220         if (conn->rmb_desc) {
1221                 bufsize = conn->rmb_desc->len;
1222                 if (!is_smcd) {
1223                         smcr_buf_unuse(conn->rmb_desc, true, lgr);
1224                 } else {
1225                         bufsize += sizeof(struct smcd_cdc_msg);
1226                         memzero_explicit(conn->rmb_desc->cpu_addr, bufsize);
1227                         WRITE_ONCE(conn->rmb_desc->used, 0);
1228                 }
1229                 SMC_STAT_RMB_SIZE(smc, is_smcd, true, false, bufsize);
1230         }
1231 }
1232
1233 /* remove a finished connection from its link group */
1234 void smc_conn_free(struct smc_connection *conn)
1235 {
1236         struct smc_link_group *lgr = conn->lgr;
1237
1238         if (!lgr || conn->freed)
1239                 /* Connection has never been registered in a
1240                  * link group, or has already been freed.
1241                  */
1242                 return;
1243
1244         conn->freed = 1;
1245         if (!smc_conn_lgr_valid(conn))
1246                 /* Connection has already unregistered from
1247                  * link group.
1248                  */
1249                 goto lgr_put;
1250
1251         if (lgr->is_smcd) {
1252                 if (!list_empty(&lgr->list))
1253                         smc_ism_unset_conn(conn);
1254                 if (smc_ism_support_dmb_nocopy(lgr->smcd))
1255                         smcd_buf_detach(conn);
1256                 tasklet_kill(&conn->rx_tsklet);
1257         } else {
1258                 smc_cdc_wait_pend_tx_wr(conn);
1259                 if (current_work() != &conn->abort_work)
1260                         cancel_work_sync(&conn->abort_work);
1261         }
1262         if (!list_empty(&lgr->list)) {
1263                 smc_buf_unuse(conn, lgr); /* allow buffer reuse */
1264                 smc_lgr_unregister_conn(conn);
1265         }
1266
1267         if (!lgr->conns_num)
1268                 smc_lgr_schedule_free_work(lgr);
1269 lgr_put:
1270         if (!lgr->is_smcd)
1271                 smcr_link_put(conn->lnk); /* link_hold in smc_conn_create() */
1272         smc_lgr_put(lgr); /* lgr_hold in smc_conn_create() */
1273 }
1274
1275 /* unregister a link from a buf_desc */
1276 static void smcr_buf_unmap_link(struct smc_buf_desc *buf_desc, bool is_rmb,
1277                                 struct smc_link *lnk)
1278 {
1279         if (is_rmb || buf_desc->is_vm)
1280                 buf_desc->is_reg_mr[lnk->link_idx] = false;
1281         if (!buf_desc->is_map_ib[lnk->link_idx])
1282                 return;
1283
1284         if ((is_rmb || buf_desc->is_vm) &&
1285             buf_desc->mr[lnk->link_idx]) {
1286                 smc_ib_put_memory_region(buf_desc->mr[lnk->link_idx]);
1287                 buf_desc->mr[lnk->link_idx] = NULL;
1288         }
1289         if (is_rmb)
1290                 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_FROM_DEVICE);
1291         else
1292                 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_TO_DEVICE);
1293
1294         sg_free_table(&buf_desc->sgt[lnk->link_idx]);
1295         buf_desc->is_map_ib[lnk->link_idx] = false;
1296 }
1297
1298 /* unmap all buffers of lgr for a deleted link */
1299 static void smcr_buf_unmap_lgr(struct smc_link *lnk)
1300 {
1301         struct smc_link_group *lgr = lnk->lgr;
1302         struct smc_buf_desc *buf_desc, *bf;
1303         int i;
1304
1305         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1306                 down_write(&lgr->rmbs_lock);
1307                 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list)
1308                         smcr_buf_unmap_link(buf_desc, true, lnk);
1309                 up_write(&lgr->rmbs_lock);
1310
1311                 down_write(&lgr->sndbufs_lock);
1312                 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i],
1313                                          list)
1314                         smcr_buf_unmap_link(buf_desc, false, lnk);
1315                 up_write(&lgr->sndbufs_lock);
1316         }
1317 }
1318
1319 static void smcr_rtoken_clear_link(struct smc_link *lnk)
1320 {
1321         struct smc_link_group *lgr = lnk->lgr;
1322         int i;
1323
1324         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1325                 lgr->rtokens[i][lnk->link_idx].rkey = 0;
1326                 lgr->rtokens[i][lnk->link_idx].dma_addr = 0;
1327         }
1328 }
1329
1330 static void __smcr_link_clear(struct smc_link *lnk)
1331 {
1332         struct smc_link_group *lgr = lnk->lgr;
1333         struct smc_ib_device *smcibdev;
1334
1335         smc_wr_free_link_mem(lnk);
1336         smc_ibdev_cnt_dec(lnk);
1337         put_device(&lnk->smcibdev->ibdev->dev);
1338         smcibdev = lnk->smcibdev;
1339         memset(lnk, 0, sizeof(struct smc_link));
1340         lnk->state = SMC_LNK_UNUSED;
1341         if (!atomic_dec_return(&smcibdev->lnk_cnt))
1342                 wake_up(&smcibdev->lnks_deleted);
1343         smc_lgr_put(lgr); /* lgr_hold in smcr_link_init() */
1344 }
1345
1346 /* must be called under lgr->llc_conf_mutex lock */
1347 void smcr_link_clear(struct smc_link *lnk, bool log)
1348 {
1349         if (!lnk->lgr || lnk->clearing ||
1350             lnk->state == SMC_LNK_UNUSED)
1351                 return;
1352         lnk->clearing = 1;
1353         lnk->peer_qpn = 0;
1354         smc_llc_link_clear(lnk, log);
1355         smcr_buf_unmap_lgr(lnk);
1356         smcr_rtoken_clear_link(lnk);
1357         smc_ib_modify_qp_error(lnk);
1358         smc_wr_free_link(lnk);
1359         smc_ib_destroy_queue_pair(lnk);
1360         smc_ib_dealloc_protection_domain(lnk);
1361         smcr_link_put(lnk); /* theoretically last link_put */
1362 }
1363
1364 void smcr_link_hold(struct smc_link *lnk)
1365 {
1366         refcount_inc(&lnk->refcnt);
1367 }
1368
1369 void smcr_link_put(struct smc_link *lnk)
1370 {
1371         if (refcount_dec_and_test(&lnk->refcnt))
1372                 __smcr_link_clear(lnk);
1373 }
1374
1375 static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb,
1376                           struct smc_buf_desc *buf_desc)
1377 {
1378         int i;
1379
1380         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1381                 smcr_buf_unmap_link(buf_desc, is_rmb, &lgr->lnk[i]);
1382
1383         if (!buf_desc->is_vm && buf_desc->pages)
1384                 __free_pages(buf_desc->pages, buf_desc->order);
1385         else if (buf_desc->is_vm && buf_desc->cpu_addr)
1386                 vfree(buf_desc->cpu_addr);
1387         kfree(buf_desc);
1388 }
1389
1390 static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb,
1391                           struct smc_buf_desc *buf_desc)
1392 {
1393         if (is_dmb) {
1394                 /* restore original buf len */
1395                 buf_desc->len += sizeof(struct smcd_cdc_msg);
1396                 smc_ism_unregister_dmb(lgr->smcd, buf_desc);
1397         } else {
1398                 kfree(buf_desc->cpu_addr);
1399         }
1400         kfree(buf_desc);
1401 }
1402
1403 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
1404                          struct smc_buf_desc *buf_desc)
1405 {
1406         if (lgr->is_smcd)
1407                 smcd_buf_free(lgr, is_rmb, buf_desc);
1408         else
1409                 smcr_buf_free(lgr, is_rmb, buf_desc);
1410 }
1411
1412 static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb)
1413 {
1414         struct smc_buf_desc *buf_desc, *bf_desc;
1415         struct list_head *buf_list;
1416         int i;
1417
1418         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1419                 if (is_rmb)
1420                         buf_list = &lgr->rmbs[i];
1421                 else
1422                         buf_list = &lgr->sndbufs[i];
1423                 list_for_each_entry_safe(buf_desc, bf_desc, buf_list,
1424                                          list) {
1425                         smc_lgr_buf_list_del(lgr, is_rmb, buf_desc);
1426                         smc_buf_free(lgr, is_rmb, buf_desc);
1427                 }
1428         }
1429 }
1430
1431 static void smc_lgr_free_bufs(struct smc_link_group *lgr)
1432 {
1433         /* free send buffers */
1434         __smc_lgr_free_bufs(lgr, false);
1435         /* free rmbs */
1436         __smc_lgr_free_bufs(lgr, true);
1437 }
1438
1439 /* won't be freed until no one accesses to lgr anymore */
1440 static void __smc_lgr_free(struct smc_link_group *lgr)
1441 {
1442         smc_lgr_free_bufs(lgr);
1443         if (lgr->is_smcd) {
1444                 if (!atomic_dec_return(&lgr->smcd->lgr_cnt))
1445                         wake_up(&lgr->smcd->lgrs_deleted);
1446         } else {
1447                 smc_wr_free_lgr_mem(lgr);
1448                 if (!atomic_dec_return(&lgr_cnt))
1449                         wake_up(&lgrs_deleted);
1450         }
1451         kfree(lgr);
1452 }
1453
1454 /* remove a link group */
1455 static void smc_lgr_free(struct smc_link_group *lgr)
1456 {
1457         int i;
1458
1459         if (!lgr->is_smcd) {
1460                 down_write(&lgr->llc_conf_mutex);
1461                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1462                         if (lgr->lnk[i].state != SMC_LNK_UNUSED)
1463                                 smcr_link_clear(&lgr->lnk[i], false);
1464                 }
1465                 up_write(&lgr->llc_conf_mutex);
1466                 smc_llc_lgr_clear(lgr);
1467         }
1468
1469         destroy_workqueue(lgr->tx_wq);
1470         if (lgr->is_smcd) {
1471                 smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
1472                 put_device(lgr->smcd->ops->get_dev(lgr->smcd));
1473         }
1474         smc_lgr_put(lgr); /* theoretically last lgr_put */
1475 }
1476
1477 void smc_lgr_hold(struct smc_link_group *lgr)
1478 {
1479         refcount_inc(&lgr->refcnt);
1480 }
1481
1482 void smc_lgr_put(struct smc_link_group *lgr)
1483 {
1484         if (refcount_dec_and_test(&lgr->refcnt))
1485                 __smc_lgr_free(lgr);
1486 }
1487
1488 static void smc_sk_wake_ups(struct smc_sock *smc)
1489 {
1490         smc->sk.sk_write_space(&smc->sk);
1491         smc->sk.sk_data_ready(&smc->sk);
1492         smc->sk.sk_state_change(&smc->sk);
1493 }
1494
1495 /* kill a connection */
1496 static void smc_conn_kill(struct smc_connection *conn, bool soft)
1497 {
1498         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1499
1500         if (conn->lgr->is_smcd && conn->lgr->peer_shutdown)
1501                 conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
1502         else
1503                 smc_close_abort(conn);
1504         conn->killed = 1;
1505         smc->sk.sk_err = ECONNABORTED;
1506         smc_sk_wake_ups(smc);
1507         if (conn->lgr->is_smcd) {
1508                 smc_ism_unset_conn(conn);
1509                 if (smc_ism_support_dmb_nocopy(conn->lgr->smcd))
1510                         smcd_buf_detach(conn);
1511                 if (soft)
1512                         tasklet_kill(&conn->rx_tsklet);
1513                 else
1514                         tasklet_unlock_wait(&conn->rx_tsklet);
1515         } else {
1516                 smc_cdc_wait_pend_tx_wr(conn);
1517         }
1518         smc_lgr_unregister_conn(conn);
1519         smc_close_active_abort(smc);
1520 }
1521
1522 static void smc_lgr_cleanup(struct smc_link_group *lgr)
1523 {
1524         if (lgr->is_smcd) {
1525                 smc_ism_signal_shutdown(lgr);
1526         } else {
1527                 u32 rsn = lgr->llc_termination_rsn;
1528
1529                 if (!rsn)
1530                         rsn = SMC_LLC_DEL_PROG_INIT_TERM;
1531                 smc_llc_send_link_delete_all(lgr, false, rsn);
1532                 smcr_lgr_link_deactivate_all(lgr);
1533         }
1534 }
1535
1536 /* terminate link group
1537  * @soft: true if link group shutdown can take its time
1538  *        false if immediate link group shutdown is required
1539  */
1540 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft)
1541 {
1542         struct smc_connection *conn;
1543         struct smc_sock *smc;
1544         struct rb_node *node;
1545
1546         if (lgr->terminating)
1547                 return; /* lgr already terminating */
1548         /* cancel free_work sync, will terminate when lgr->freeing is set */
1549         cancel_delayed_work(&lgr->free_work);
1550         lgr->terminating = 1;
1551
1552         /* kill remaining link group connections */
1553         read_lock_bh(&lgr->conns_lock);
1554         node = rb_first(&lgr->conns_all);
1555         while (node) {
1556                 read_unlock_bh(&lgr->conns_lock);
1557                 conn = rb_entry(node, struct smc_connection, alert_node);
1558                 smc = container_of(conn, struct smc_sock, conn);
1559                 sock_hold(&smc->sk); /* sock_put below */
1560                 lock_sock(&smc->sk);
1561                 smc_conn_kill(conn, soft);
1562                 release_sock(&smc->sk);
1563                 sock_put(&smc->sk); /* sock_hold above */
1564                 read_lock_bh(&lgr->conns_lock);
1565                 node = rb_first(&lgr->conns_all);
1566         }
1567         read_unlock_bh(&lgr->conns_lock);
1568         smc_lgr_cleanup(lgr);
1569         smc_lgr_free(lgr);
1570 }
1571
1572 /* unlink link group and schedule termination */
1573 void smc_lgr_terminate_sched(struct smc_link_group *lgr)
1574 {
1575         spinlock_t *lgr_lock;
1576
1577         smc_lgr_list_head(lgr, &lgr_lock);
1578         spin_lock_bh(lgr_lock);
1579         if (list_empty(&lgr->list) || lgr->terminating || lgr->freeing) {
1580                 spin_unlock_bh(lgr_lock);
1581                 return; /* lgr already terminating */
1582         }
1583         list_del_init(&lgr->list);
1584         lgr->freeing = 1;
1585         spin_unlock_bh(lgr_lock);
1586         schedule_work(&lgr->terminate_work);
1587 }
1588
1589 /* Called when peer lgr shutdown (regularly or abnormally) is received */
1590 void smc_smcd_terminate(struct smcd_dev *dev, struct smcd_gid *peer_gid,
1591                         unsigned short vlan)
1592 {
1593         struct smc_link_group *lgr, *l;
1594         LIST_HEAD(lgr_free_list);
1595
1596         /* run common cleanup function and build free list */
1597         spin_lock_bh(&dev->lgr_lock);
1598         list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) {
1599                 if ((!peer_gid->gid ||
1600                      (lgr->peer_gid.gid == peer_gid->gid &&
1601                       !smc_ism_is_emulated(dev) ? 1 :
1602                       lgr->peer_gid.gid_ext == peer_gid->gid_ext)) &&
1603                     (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
1604                         if (peer_gid->gid) /* peer triggered termination */
1605                                 lgr->peer_shutdown = 1;
1606                         list_move(&lgr->list, &lgr_free_list);
1607                         lgr->freeing = 1;
1608                 }
1609         }
1610         spin_unlock_bh(&dev->lgr_lock);
1611
1612         /* cancel the regular free workers and actually free lgrs */
1613         list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
1614                 list_del_init(&lgr->list);
1615                 schedule_work(&lgr->terminate_work);
1616         }
1617 }
1618
1619 /* Called when an SMCD device is removed or the smc module is unloaded */
1620 void smc_smcd_terminate_all(struct smcd_dev *smcd)
1621 {
1622         struct smc_link_group *lgr, *lg;
1623         LIST_HEAD(lgr_free_list);
1624
1625         spin_lock_bh(&smcd->lgr_lock);
1626         list_splice_init(&smcd->lgr_list, &lgr_free_list);
1627         list_for_each_entry(lgr, &lgr_free_list, list)
1628                 lgr->freeing = 1;
1629         spin_unlock_bh(&smcd->lgr_lock);
1630
1631         list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1632                 list_del_init(&lgr->list);
1633                 __smc_lgr_terminate(lgr, false);
1634         }
1635
1636         if (atomic_read(&smcd->lgr_cnt))
1637                 wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt));
1638 }
1639
1640 /* Called when an SMCR device is removed or the smc module is unloaded.
1641  * If smcibdev is given, all SMCR link groups using this device are terminated.
1642  * If smcibdev is NULL, all SMCR link groups are terminated.
1643  */
1644 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
1645 {
1646         struct smc_link_group *lgr, *lg;
1647         LIST_HEAD(lgr_free_list);
1648         int i;
1649
1650         spin_lock_bh(&smc_lgr_list.lock);
1651         if (!smcibdev) {
1652                 list_splice_init(&smc_lgr_list.list, &lgr_free_list);
1653                 list_for_each_entry(lgr, &lgr_free_list, list)
1654                         lgr->freeing = 1;
1655         } else {
1656                 list_for_each_entry_safe(lgr, lg, &smc_lgr_list.list, list) {
1657                         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1658                                 if (lgr->lnk[i].smcibdev == smcibdev)
1659                                         smcr_link_down_cond_sched(&lgr->lnk[i]);
1660                         }
1661                 }
1662         }
1663         spin_unlock_bh(&smc_lgr_list.lock);
1664
1665         list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1666                 list_del_init(&lgr->list);
1667                 smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_OP_INIT_TERM);
1668                 __smc_lgr_terminate(lgr, false);
1669         }
1670
1671         if (smcibdev) {
1672                 if (atomic_read(&smcibdev->lnk_cnt))
1673                         wait_event(smcibdev->lnks_deleted,
1674                                    !atomic_read(&smcibdev->lnk_cnt));
1675         } else {
1676                 if (atomic_read(&lgr_cnt))
1677                         wait_event(lgrs_deleted, !atomic_read(&lgr_cnt));
1678         }
1679 }
1680
1681 /* set new lgr type and clear all asymmetric link tagging */
1682 void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type)
1683 {
1684         char *lgr_type = "";
1685         int i;
1686
1687         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1688                 if (smc_link_usable(&lgr->lnk[i]))
1689                         lgr->lnk[i].link_is_asym = false;
1690         if (lgr->type == new_type)
1691                 return;
1692         lgr->type = new_type;
1693
1694         switch (lgr->type) {
1695         case SMC_LGR_NONE:
1696                 lgr_type = "NONE";
1697                 break;
1698         case SMC_LGR_SINGLE:
1699                 lgr_type = "SINGLE";
1700                 break;
1701         case SMC_LGR_SYMMETRIC:
1702                 lgr_type = "SYMMETRIC";
1703                 break;
1704         case SMC_LGR_ASYMMETRIC_PEER:
1705                 lgr_type = "ASYMMETRIC_PEER";
1706                 break;
1707         case SMC_LGR_ASYMMETRIC_LOCAL:
1708                 lgr_type = "ASYMMETRIC_LOCAL";
1709                 break;
1710         }
1711         pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu state changed: "
1712                             "%s, pnetid %.16s\n", SMC_LGR_ID_SIZE, &lgr->id,
1713                             lgr->net->net_cookie, lgr_type, lgr->pnet_id);
1714 }
1715
1716 /* set new lgr type and tag a link as asymmetric */
1717 void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
1718                             enum smc_lgr_type new_type, int asym_lnk_idx)
1719 {
1720         smcr_lgr_set_type(lgr, new_type);
1721         lgr->lnk[asym_lnk_idx].link_is_asym = true;
1722 }
1723
1724 /* abort connection, abort_work scheduled from tasklet context */
1725 static void smc_conn_abort_work(struct work_struct *work)
1726 {
1727         struct smc_connection *conn = container_of(work,
1728                                                    struct smc_connection,
1729                                                    abort_work);
1730         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1731
1732         lock_sock(&smc->sk);
1733         smc_conn_kill(conn, true);
1734         release_sock(&smc->sk);
1735         sock_put(&smc->sk); /* sock_hold done by schedulers of abort_work */
1736 }
1737
1738 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport)
1739 {
1740         struct smc_link_group *lgr, *n;
1741
1742         spin_lock_bh(&smc_lgr_list.lock);
1743         list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1744                 struct smc_link *link;
1745
1746                 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1747                             SMC_MAX_PNETID_LEN) ||
1748                     lgr->type == SMC_LGR_SYMMETRIC ||
1749                     lgr->type == SMC_LGR_ASYMMETRIC_PEER ||
1750                     !rdma_dev_access_netns(smcibdev->ibdev, lgr->net))
1751                         continue;
1752
1753                 if (lgr->type == SMC_LGR_SINGLE && lgr->max_links <= 1)
1754                         continue;
1755
1756                 /* trigger local add link processing */
1757                 link = smc_llc_usable_link(lgr);
1758                 if (link)
1759                         smc_llc_add_link_local(link);
1760         }
1761         spin_unlock_bh(&smc_lgr_list.lock);
1762 }
1763
1764 /* link is down - switch connections to alternate link,
1765  * must be called under lgr->llc_conf_mutex lock
1766  */
1767 static void smcr_link_down(struct smc_link *lnk)
1768 {
1769         struct smc_link_group *lgr = lnk->lgr;
1770         struct smc_link *to_lnk;
1771         int del_link_id;
1772
1773         if (!lgr || lnk->state == SMC_LNK_UNUSED || list_empty(&lgr->list))
1774                 return;
1775
1776         to_lnk = smc_switch_conns(lgr, lnk, true);
1777         if (!to_lnk) { /* no backup link available */
1778                 smcr_link_clear(lnk, true);
1779                 return;
1780         }
1781         smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
1782         del_link_id = lnk->link_id;
1783
1784         if (lgr->role == SMC_SERV) {
1785                 /* trigger local delete link processing */
1786                 smc_llc_srv_delete_link_local(to_lnk, del_link_id);
1787         } else {
1788                 if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
1789                         /* another llc task is ongoing */
1790                         up_write(&lgr->llc_conf_mutex);
1791                         wait_event_timeout(lgr->llc_flow_waiter,
1792                                 (list_empty(&lgr->list) ||
1793                                  lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE),
1794                                 SMC_LLC_WAIT_TIME);
1795                         down_write(&lgr->llc_conf_mutex);
1796                 }
1797                 if (!list_empty(&lgr->list)) {
1798                         smc_llc_send_delete_link(to_lnk, del_link_id,
1799                                                  SMC_LLC_REQ, true,
1800                                                  SMC_LLC_DEL_LOST_PATH);
1801                         smcr_link_clear(lnk, true);
1802                 }
1803                 wake_up(&lgr->llc_flow_waiter); /* wake up next waiter */
1804         }
1805 }
1806
1807 /* must be called under lgr->llc_conf_mutex lock */
1808 void smcr_link_down_cond(struct smc_link *lnk)
1809 {
1810         if (smc_link_downing(&lnk->state)) {
1811                 trace_smcr_link_down(lnk, __builtin_return_address(0));
1812                 smcr_link_down(lnk);
1813         }
1814 }
1815
1816 /* will get the lgr->llc_conf_mutex lock */
1817 void smcr_link_down_cond_sched(struct smc_link *lnk)
1818 {
1819         if (smc_link_downing(&lnk->state)) {
1820                 trace_smcr_link_down(lnk, __builtin_return_address(0));
1821                 smcr_link_hold(lnk); /* smcr_link_put in link_down_wrk */
1822                 if (!schedule_work(&lnk->link_down_wrk))
1823                         smcr_link_put(lnk);
1824         }
1825 }
1826
1827 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport)
1828 {
1829         struct smc_link_group *lgr, *n;
1830         int i;
1831
1832         list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1833                 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1834                             SMC_MAX_PNETID_LEN))
1835                         continue; /* lgr is not affected */
1836                 if (list_empty(&lgr->list))
1837                         continue;
1838                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1839                         struct smc_link *lnk = &lgr->lnk[i];
1840
1841                         if (smc_link_usable(lnk) &&
1842                             lnk->smcibdev == smcibdev && lnk->ibport == ibport)
1843                                 smcr_link_down_cond_sched(lnk);
1844                 }
1845         }
1846 }
1847
1848 static void smc_link_down_work(struct work_struct *work)
1849 {
1850         struct smc_link *link = container_of(work, struct smc_link,
1851                                              link_down_wrk);
1852         struct smc_link_group *lgr = link->lgr;
1853
1854         if (list_empty(&lgr->list))
1855                 goto out;
1856         wake_up_all(&lgr->llc_msg_waiter);
1857         down_write(&lgr->llc_conf_mutex);
1858         smcr_link_down(link);
1859         up_write(&lgr->llc_conf_mutex);
1860
1861 out:
1862         smcr_link_put(link); /* smcr_link_hold by schedulers of link_down_work */
1863 }
1864
1865 static int smc_vlan_by_tcpsk_walk(struct net_device *lower_dev,
1866                                   struct netdev_nested_priv *priv)
1867 {
1868         unsigned short *vlan_id = (unsigned short *)priv->data;
1869
1870         if (is_vlan_dev(lower_dev)) {
1871                 *vlan_id = vlan_dev_vlan_id(lower_dev);
1872                 return 1;
1873         }
1874
1875         return 0;
1876 }
1877
1878 /* Determine vlan of internal TCP socket. */
1879 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
1880 {
1881         struct dst_entry *dst = sk_dst_get(clcsock->sk);
1882         struct netdev_nested_priv priv;
1883         struct net_device *ndev;
1884         int rc = 0;
1885
1886         ini->vlan_id = 0;
1887         if (!dst) {
1888                 rc = -ENOTCONN;
1889                 goto out;
1890         }
1891         if (!dst->dev) {
1892                 rc = -ENODEV;
1893                 goto out_rel;
1894         }
1895
1896         ndev = dst->dev;
1897         if (is_vlan_dev(ndev)) {
1898                 ini->vlan_id = vlan_dev_vlan_id(ndev);
1899                 goto out_rel;
1900         }
1901
1902         priv.data = (void *)&ini->vlan_id;
1903         rtnl_lock();
1904         netdev_walk_all_lower_dev(ndev, smc_vlan_by_tcpsk_walk, &priv);
1905         rtnl_unlock();
1906
1907 out_rel:
1908         dst_release(dst);
1909 out:
1910         return rc;
1911 }
1912
1913 static bool smcr_lgr_match(struct smc_link_group *lgr, u8 smcr_version,
1914                            u8 peer_systemid[],
1915                            u8 peer_gid[],
1916                            u8 peer_mac_v1[],
1917                            enum smc_lgr_role role, u32 clcqpn,
1918                            struct net *net)
1919 {
1920         struct smc_link *lnk;
1921         int i;
1922
1923         if (memcmp(lgr->peer_systemid, peer_systemid, SMC_SYSTEMID_LEN) ||
1924             lgr->role != role)
1925                 return false;
1926
1927         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1928                 lnk = &lgr->lnk[i];
1929
1930                 if (!smc_link_active(lnk))
1931                         continue;
1932                 /* use verbs API to check netns, instead of lgr->net */
1933                 if (!rdma_dev_access_netns(lnk->smcibdev->ibdev, net))
1934                         return false;
1935                 if ((lgr->role == SMC_SERV || lnk->peer_qpn == clcqpn) &&
1936                     !memcmp(lnk->peer_gid, peer_gid, SMC_GID_SIZE) &&
1937                     (smcr_version == SMC_V2 ||
1938                      !memcmp(lnk->peer_mac, peer_mac_v1, ETH_ALEN)))
1939                         return true;
1940         }
1941         return false;
1942 }
1943
1944 static bool smcd_lgr_match(struct smc_link_group *lgr,
1945                            struct smcd_dev *smcismdev,
1946                            struct smcd_gid *peer_gid)
1947 {
1948         if (lgr->peer_gid.gid != peer_gid->gid ||
1949             lgr->smcd != smcismdev)
1950                 return false;
1951
1952         if (smc_ism_is_emulated(smcismdev) &&
1953             lgr->peer_gid.gid_ext != peer_gid->gid_ext)
1954                 return false;
1955
1956         return true;
1957 }
1958
1959 /* create a new SMC connection (and a new link group if necessary) */
1960 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
1961 {
1962         struct smc_connection *conn = &smc->conn;
1963         struct net *net = sock_net(&smc->sk);
1964         struct list_head *lgr_list;
1965         struct smc_link_group *lgr;
1966         enum smc_lgr_role role;
1967         spinlock_t *lgr_lock;
1968         int rc = 0;
1969
1970         lgr_list = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_list :
1971                                   &smc_lgr_list.list;
1972         lgr_lock = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_lock :
1973                                   &smc_lgr_list.lock;
1974         ini->first_contact_local = 1;
1975         role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
1976         if (role == SMC_CLNT && ini->first_contact_peer)
1977                 /* create new link group as well */
1978                 goto create;
1979
1980         /* determine if an existing link group can be reused */
1981         spin_lock_bh(lgr_lock);
1982         list_for_each_entry(lgr, lgr_list, list) {
1983                 write_lock_bh(&lgr->conns_lock);
1984                 if ((ini->is_smcd ?
1985                      smcd_lgr_match(lgr, ini->ism_dev[ini->ism_selected],
1986                                     &ini->ism_peer_gid[ini->ism_selected]) :
1987                      smcr_lgr_match(lgr, ini->smcr_version,
1988                                     ini->peer_systemid,
1989                                     ini->peer_gid, ini->peer_mac, role,
1990                                     ini->ib_clcqpn, net)) &&
1991                     !lgr->sync_err &&
1992                     (ini->smcd_version == SMC_V2 ||
1993                      lgr->vlan_id == ini->vlan_id) &&
1994                     (role == SMC_CLNT || ini->is_smcd ||
1995                     (lgr->conns_num < lgr->max_conns &&
1996                       !bitmap_full(lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX)))) {
1997                         /* link group found */
1998                         ini->first_contact_local = 0;
1999                         conn->lgr = lgr;
2000                         rc = smc_lgr_register_conn(conn, false);
2001                         write_unlock_bh(&lgr->conns_lock);
2002                         if (!rc && delayed_work_pending(&lgr->free_work))
2003                                 cancel_delayed_work(&lgr->free_work);
2004                         break;
2005                 }
2006                 write_unlock_bh(&lgr->conns_lock);
2007         }
2008         spin_unlock_bh(lgr_lock);
2009         if (rc)
2010                 return rc;
2011
2012         if (role == SMC_CLNT && !ini->first_contact_peer &&
2013             ini->first_contact_local) {
2014                 /* Server reuses a link group, but Client wants to start
2015                  * a new one
2016                  * send out_of_sync decline, reason synchr. error
2017                  */
2018                 return SMC_CLC_DECL_SYNCERR;
2019         }
2020
2021 create:
2022         if (ini->first_contact_local) {
2023                 rc = smc_lgr_create(smc, ini);
2024                 if (rc)
2025                         goto out;
2026                 lgr = conn->lgr;
2027                 write_lock_bh(&lgr->conns_lock);
2028                 rc = smc_lgr_register_conn(conn, true);
2029                 write_unlock_bh(&lgr->conns_lock);
2030                 if (rc) {
2031                         smc_lgr_cleanup_early(lgr);
2032                         goto out;
2033                 }
2034         }
2035         smc_lgr_hold(conn->lgr); /* lgr_put in smc_conn_free() */
2036         if (!conn->lgr->is_smcd)
2037                 smcr_link_hold(conn->lnk); /* link_put in smc_conn_free() */
2038         conn->freed = 0;
2039         conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
2040         conn->local_tx_ctrl.len = SMC_WR_TX_SIZE;
2041         conn->urg_state = SMC_URG_READ;
2042         init_waitqueue_head(&conn->cdc_pend_tx_wq);
2043         INIT_WORK(&smc->conn.abort_work, smc_conn_abort_work);
2044         if (ini->is_smcd) {
2045                 conn->rx_off = sizeof(struct smcd_cdc_msg);
2046                 smcd_cdc_rx_init(conn); /* init tasklet for this conn */
2047         } else {
2048                 conn->rx_off = 0;
2049         }
2050 #ifndef KERNEL_HAS_ATOMIC64
2051         spin_lock_init(&conn->acurs_lock);
2052 #endif
2053
2054 out:
2055         return rc;
2056 }
2057
2058 #define SMCD_DMBE_SIZES         6 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */
2059 #define SMCR_RMBE_SIZES         15 /* 0 -> 16KB, 1 -> 32KB, .. 15 -> 512MB */
2060
2061 /* convert the RMB size into the compressed notation (minimum 16K, see
2062  * SMCD/R_DMBE_SIZES.
2063  * In contrast to plain ilog2, this rounds towards the next power of 2,
2064  * so the socket application gets at least its desired sndbuf / rcvbuf size.
2065  */
2066 static u8 smc_compress_bufsize(int size, bool is_smcd, bool is_rmb)
2067 {
2068         u8 compressed;
2069
2070         if (size <= SMC_BUF_MIN_SIZE)
2071                 return 0;
2072
2073         size = (size - 1) >> 14;  /* convert to 16K multiple */
2074         compressed = min_t(u8, ilog2(size) + 1,
2075                            is_smcd ? SMCD_DMBE_SIZES : SMCR_RMBE_SIZES);
2076
2077 #ifdef CONFIG_ARCH_NO_SG_CHAIN
2078         if (!is_smcd && is_rmb)
2079                 /* RMBs are backed by & limited to max size of scatterlists */
2080                 compressed = min_t(u8, compressed, ilog2((SG_MAX_SINGLE_ALLOC * PAGE_SIZE) >> 14));
2081 #endif
2082
2083         return compressed;
2084 }
2085
2086 /* convert the RMB size from compressed notation into integer */
2087 int smc_uncompress_bufsize(u8 compressed)
2088 {
2089         u32 size;
2090
2091         size = 0x00000001 << (((int)compressed) + 14);
2092         return (int)size;
2093 }
2094
2095 /* try to reuse a sndbuf or rmb description slot for a certain
2096  * buffer size; if not available, return NULL
2097  */
2098 static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize,
2099                                              struct rw_semaphore *lock,
2100                                              struct list_head *buf_list)
2101 {
2102         struct smc_buf_desc *buf_slot;
2103
2104         down_read(lock);
2105         list_for_each_entry(buf_slot, buf_list, list) {
2106                 if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
2107                         up_read(lock);
2108                         return buf_slot;
2109                 }
2110         }
2111         up_read(lock);
2112         return NULL;
2113 }
2114
2115 /* one of the conditions for announcing a receiver's current window size is
2116  * that it "results in a minimum increase in the window size of 10% of the
2117  * receive buffer space" [RFC7609]
2118  */
2119 static inline int smc_rmb_wnd_update_limit(int rmbe_size)
2120 {
2121         return max_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
2122 }
2123
2124 /* map an buf to a link */
2125 static int smcr_buf_map_link(struct smc_buf_desc *buf_desc, bool is_rmb,
2126                              struct smc_link *lnk)
2127 {
2128         int rc, i, nents, offset, buf_size, size, access_flags;
2129         struct scatterlist *sg;
2130         void *buf;
2131
2132         if (buf_desc->is_map_ib[lnk->link_idx])
2133                 return 0;
2134
2135         if (buf_desc->is_vm) {
2136                 buf = buf_desc->cpu_addr;
2137                 buf_size = buf_desc->len;
2138                 offset = offset_in_page(buf_desc->cpu_addr);
2139                 nents = PAGE_ALIGN(buf_size + offset) / PAGE_SIZE;
2140         } else {
2141                 nents = 1;
2142         }
2143
2144         rc = sg_alloc_table(&buf_desc->sgt[lnk->link_idx], nents, GFP_KERNEL);
2145         if (rc)
2146                 return rc;
2147
2148         if (buf_desc->is_vm) {
2149                 /* virtually contiguous buffer */
2150                 for_each_sg(buf_desc->sgt[lnk->link_idx].sgl, sg, nents, i) {
2151                         size = min_t(int, PAGE_SIZE - offset, buf_size);
2152                         sg_set_page(sg, vmalloc_to_page(buf), size, offset);
2153                         buf += size / sizeof(*buf);
2154                         buf_size -= size;
2155                         offset = 0;
2156                 }
2157         } else {
2158                 /* physically contiguous buffer */
2159                 sg_set_buf(buf_desc->sgt[lnk->link_idx].sgl,
2160                            buf_desc->cpu_addr, buf_desc->len);
2161         }
2162
2163         /* map sg table to DMA address */
2164         rc = smc_ib_buf_map_sg(lnk, buf_desc,
2165                                is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2166         /* SMC protocol depends on mapping to one DMA address only */
2167         if (rc != nents) {
2168                 rc = -EAGAIN;
2169                 goto free_table;
2170         }
2171
2172         buf_desc->is_dma_need_sync |=
2173                 smc_ib_is_sg_need_sync(lnk, buf_desc) << lnk->link_idx;
2174
2175         if (is_rmb || buf_desc->is_vm) {
2176                 /* create a new memory region for the RMB or vzalloced sndbuf */
2177                 access_flags = is_rmb ?
2178                                IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
2179                                IB_ACCESS_LOCAL_WRITE;
2180
2181                 rc = smc_ib_get_memory_region(lnk->roce_pd, access_flags,
2182                                               buf_desc, lnk->link_idx);
2183                 if (rc)
2184                         goto buf_unmap;
2185                 smc_ib_sync_sg_for_device(lnk, buf_desc,
2186                                           is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2187         }
2188         buf_desc->is_map_ib[lnk->link_idx] = true;
2189         return 0;
2190
2191 buf_unmap:
2192         smc_ib_buf_unmap_sg(lnk, buf_desc,
2193                             is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2194 free_table:
2195         sg_free_table(&buf_desc->sgt[lnk->link_idx]);
2196         return rc;
2197 }
2198
2199 /* register a new buf on IB device, rmb or vzalloced sndbuf
2200  * must be called under lgr->llc_conf_mutex lock
2201  */
2202 int smcr_link_reg_buf(struct smc_link *link, struct smc_buf_desc *buf_desc)
2203 {
2204         if (list_empty(&link->lgr->list))
2205                 return -ENOLINK;
2206         if (!buf_desc->is_reg_mr[link->link_idx]) {
2207                 /* register memory region for new buf */
2208                 if (buf_desc->is_vm)
2209                         buf_desc->mr[link->link_idx]->iova =
2210                                 (uintptr_t)buf_desc->cpu_addr;
2211                 if (smc_wr_reg_send(link, buf_desc->mr[link->link_idx])) {
2212                         buf_desc->is_reg_err = true;
2213                         return -EFAULT;
2214                 }
2215                 buf_desc->is_reg_mr[link->link_idx] = true;
2216         }
2217         return 0;
2218 }
2219
2220 static int _smcr_buf_map_lgr(struct smc_link *lnk, struct rw_semaphore *lock,
2221                              struct list_head *lst, bool is_rmb)
2222 {
2223         struct smc_buf_desc *buf_desc, *bf;
2224         int rc = 0;
2225
2226         down_write(lock);
2227         list_for_each_entry_safe(buf_desc, bf, lst, list) {
2228                 if (!buf_desc->used)
2229                         continue;
2230                 rc = smcr_buf_map_link(buf_desc, is_rmb, lnk);
2231                 if (rc)
2232                         goto out;
2233         }
2234 out:
2235         up_write(lock);
2236         return rc;
2237 }
2238
2239 /* map all used buffers of lgr for a new link */
2240 int smcr_buf_map_lgr(struct smc_link *lnk)
2241 {
2242         struct smc_link_group *lgr = lnk->lgr;
2243         int i, rc = 0;
2244
2245         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2246                 rc = _smcr_buf_map_lgr(lnk, &lgr->rmbs_lock,
2247                                        &lgr->rmbs[i], true);
2248                 if (rc)
2249                         return rc;
2250                 rc = _smcr_buf_map_lgr(lnk, &lgr->sndbufs_lock,
2251                                        &lgr->sndbufs[i], false);
2252                 if (rc)
2253                         return rc;
2254         }
2255         return 0;
2256 }
2257
2258 /* register all used buffers of lgr for a new link,
2259  * must be called under lgr->llc_conf_mutex lock
2260  */
2261 int smcr_buf_reg_lgr(struct smc_link *lnk)
2262 {
2263         struct smc_link_group *lgr = lnk->lgr;
2264         struct smc_buf_desc *buf_desc, *bf;
2265         int i, rc = 0;
2266
2267         /* reg all RMBs for a new link */
2268         down_write(&lgr->rmbs_lock);
2269         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2270                 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list) {
2271                         if (!buf_desc->used)
2272                                 continue;
2273                         rc = smcr_link_reg_buf(lnk, buf_desc);
2274                         if (rc) {
2275                                 up_write(&lgr->rmbs_lock);
2276                                 return rc;
2277                         }
2278                 }
2279         }
2280         up_write(&lgr->rmbs_lock);
2281
2282         if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
2283                 return rc;
2284
2285         /* reg all vzalloced sndbufs for a new link */
2286         down_write(&lgr->sndbufs_lock);
2287         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2288                 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i], list) {
2289                         if (!buf_desc->used || !buf_desc->is_vm)
2290                                 continue;
2291                         rc = smcr_link_reg_buf(lnk, buf_desc);
2292                         if (rc) {
2293                                 up_write(&lgr->sndbufs_lock);
2294                                 return rc;
2295                         }
2296                 }
2297         }
2298         up_write(&lgr->sndbufs_lock);
2299         return rc;
2300 }
2301
2302 static struct smc_buf_desc *smcr_new_buf_create(struct smc_link_group *lgr,
2303                                                 int bufsize)
2304 {
2305         struct smc_buf_desc *buf_desc;
2306
2307         /* try to alloc a new buffer */
2308         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
2309         if (!buf_desc)
2310                 return ERR_PTR(-ENOMEM);
2311
2312         switch (lgr->buf_type) {
2313         case SMCR_PHYS_CONT_BUFS:
2314         case SMCR_MIXED_BUFS:
2315                 buf_desc->order = get_order(bufsize);
2316                 buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN |
2317                                               __GFP_NOMEMALLOC | __GFP_COMP |
2318                                               __GFP_NORETRY | __GFP_ZERO,
2319                                               buf_desc->order);
2320                 if (buf_desc->pages) {
2321                         buf_desc->cpu_addr =
2322                                 (void *)page_address(buf_desc->pages);
2323                         buf_desc->len = bufsize;
2324                         buf_desc->is_vm = false;
2325                         break;
2326                 }
2327                 if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
2328                         goto out;
2329                 fallthrough;    // try virtually contiguous buf
2330         case SMCR_VIRT_CONT_BUFS:
2331                 buf_desc->order = get_order(bufsize);
2332                 buf_desc->cpu_addr = vzalloc(PAGE_SIZE << buf_desc->order);
2333                 if (!buf_desc->cpu_addr)
2334                         goto out;
2335                 buf_desc->pages = NULL;
2336                 buf_desc->len = bufsize;
2337                 buf_desc->is_vm = true;
2338                 break;
2339         }
2340         return buf_desc;
2341
2342 out:
2343         kfree(buf_desc);
2344         return ERR_PTR(-EAGAIN);
2345 }
2346
2347 /* map buf_desc on all usable links,
2348  * unused buffers stay mapped as long as the link is up
2349  */
2350 static int smcr_buf_map_usable_links(struct smc_link_group *lgr,
2351                                      struct smc_buf_desc *buf_desc, bool is_rmb)
2352 {
2353         int i, rc = 0, cnt = 0;
2354
2355         /* protect against parallel link reconfiguration */
2356         down_read(&lgr->llc_conf_mutex);
2357         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2358                 struct smc_link *lnk = &lgr->lnk[i];
2359
2360                 if (!smc_link_usable(lnk))
2361                         continue;
2362                 if (smcr_buf_map_link(buf_desc, is_rmb, lnk)) {
2363                         rc = -ENOMEM;
2364                         goto out;
2365                 }
2366                 cnt++;
2367         }
2368 out:
2369         up_read(&lgr->llc_conf_mutex);
2370         if (!rc && !cnt)
2371                 rc = -EINVAL;
2372         return rc;
2373 }
2374
2375 static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr,
2376                                                 bool is_dmb, int bufsize)
2377 {
2378         struct smc_buf_desc *buf_desc;
2379         int rc;
2380
2381         /* try to alloc a new DMB */
2382         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
2383         if (!buf_desc)
2384                 return ERR_PTR(-ENOMEM);
2385         if (is_dmb) {
2386                 rc = smc_ism_register_dmb(lgr, bufsize, buf_desc);
2387                 if (rc) {
2388                         kfree(buf_desc);
2389                         if (rc == -ENOMEM)
2390                                 return ERR_PTR(-EAGAIN);
2391                         if (rc == -ENOSPC)
2392                                 return ERR_PTR(-ENOSPC);
2393                         return ERR_PTR(-EIO);
2394                 }
2395                 buf_desc->pages = virt_to_page(buf_desc->cpu_addr);
2396                 /* CDC header stored in buf. So, pretend it was smaller */
2397                 buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg);
2398         } else {
2399                 buf_desc->cpu_addr = kzalloc(bufsize, GFP_KERNEL |
2400                                              __GFP_NOWARN | __GFP_NORETRY |
2401                                              __GFP_NOMEMALLOC);
2402                 if (!buf_desc->cpu_addr) {
2403                         kfree(buf_desc);
2404                         return ERR_PTR(-EAGAIN);
2405                 }
2406                 buf_desc->len = bufsize;
2407         }
2408         return buf_desc;
2409 }
2410
2411 static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb)
2412 {
2413         struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM);
2414         struct smc_connection *conn = &smc->conn;
2415         struct smc_link_group *lgr = conn->lgr;
2416         struct list_head *buf_list;
2417         int bufsize, bufsize_comp;
2418         struct rw_semaphore *lock;      /* lock buffer list */
2419         bool is_dgraded = false;
2420
2421         if (is_rmb)
2422                 /* use socket recv buffer size (w/o overhead) as start value */
2423                 bufsize = smc->sk.sk_rcvbuf / 2;
2424         else
2425                 /* use socket send buffer size (w/o overhead) as start value */
2426                 bufsize = smc->sk.sk_sndbuf / 2;
2427
2428         for (bufsize_comp = smc_compress_bufsize(bufsize, is_smcd, is_rmb);
2429              bufsize_comp >= 0; bufsize_comp--) {
2430                 if (is_rmb) {
2431                         lock = &lgr->rmbs_lock;
2432                         buf_list = &lgr->rmbs[bufsize_comp];
2433                 } else {
2434                         lock = &lgr->sndbufs_lock;
2435                         buf_list = &lgr->sndbufs[bufsize_comp];
2436                 }
2437                 bufsize = smc_uncompress_bufsize(bufsize_comp);
2438
2439                 /* check for reusable slot in the link group */
2440                 buf_desc = smc_buf_get_slot(bufsize_comp, lock, buf_list);
2441                 if (buf_desc) {
2442                         buf_desc->is_dma_need_sync = 0;
2443                         SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, true, bufsize);
2444                         SMC_STAT_BUF_REUSE(smc, is_smcd, is_rmb);
2445                         break; /* found reusable slot */
2446                 }
2447
2448                 if (is_smcd)
2449                         buf_desc = smcd_new_buf_create(lgr, is_rmb, bufsize);
2450                 else
2451                         buf_desc = smcr_new_buf_create(lgr, bufsize);
2452
2453                 if (PTR_ERR(buf_desc) == -ENOMEM)
2454                         break;
2455                 if (IS_ERR(buf_desc)) {
2456                         if (!is_dgraded) {
2457                                 is_dgraded = true;
2458                                 SMC_STAT_RMB_DOWNGRADED(smc, is_smcd, is_rmb);
2459                         }
2460                         continue;
2461                 }
2462
2463                 SMC_STAT_RMB_ALLOC(smc, is_smcd, is_rmb);
2464                 SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, true, bufsize);
2465                 buf_desc->used = 1;
2466                 down_write(lock);
2467                 smc_lgr_buf_list_add(lgr, is_rmb, buf_list, buf_desc);
2468                 up_write(lock);
2469                 break; /* found */
2470         }
2471
2472         if (IS_ERR(buf_desc))
2473                 return PTR_ERR(buf_desc);
2474
2475         if (!is_smcd) {
2476                 if (smcr_buf_map_usable_links(lgr, buf_desc, is_rmb)) {
2477                         smcr_buf_unuse(buf_desc, is_rmb, lgr);
2478                         return -ENOMEM;
2479                 }
2480         }
2481
2482         if (is_rmb) {
2483                 conn->rmb_desc = buf_desc;
2484                 conn->rmbe_size_comp = bufsize_comp;
2485                 smc->sk.sk_rcvbuf = bufsize * 2;
2486                 atomic_set(&conn->bytes_to_rcv, 0);
2487                 conn->rmbe_update_limit =
2488                         smc_rmb_wnd_update_limit(buf_desc->len);
2489                 if (is_smcd)
2490                         smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */
2491         } else {
2492                 conn->sndbuf_desc = buf_desc;
2493                 smc->sk.sk_sndbuf = bufsize * 2;
2494                 atomic_set(&conn->sndbuf_space, bufsize);
2495         }
2496         return 0;
2497 }
2498
2499 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
2500 {
2501         if (!conn->sndbuf_desc->is_dma_need_sync)
2502                 return;
2503         if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd ||
2504             !smc_link_active(conn->lnk))
2505                 return;
2506         smc_ib_sync_sg_for_device(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
2507 }
2508
2509 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
2510 {
2511         int i;
2512
2513         if (!conn->rmb_desc->is_dma_need_sync)
2514                 return;
2515         if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd)
2516                 return;
2517         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2518                 if (!smc_link_active(&conn->lgr->lnk[i]))
2519                         continue;
2520                 smc_ib_sync_sg_for_cpu(&conn->lgr->lnk[i], conn->rmb_desc,
2521                                        DMA_FROM_DEVICE);
2522         }
2523 }
2524
2525 /* create the send and receive buffer for an SMC socket;
2526  * receive buffers are called RMBs;
2527  * (even though the SMC protocol allows more than one RMB-element per RMB,
2528  * the Linux implementation uses just one RMB-element per RMB, i.e. uses an
2529  * extra RMB for every connection in a link group
2530  */
2531 int smc_buf_create(struct smc_sock *smc, bool is_smcd)
2532 {
2533         int rc;
2534
2535         /* create send buffer */
2536         if (is_smcd &&
2537             smc_ism_support_dmb_nocopy(smc->conn.lgr->smcd))
2538                 goto create_rmb;
2539
2540         rc = __smc_buf_create(smc, is_smcd, false);
2541         if (rc)
2542                 return rc;
2543
2544 create_rmb:
2545         /* create rmb */
2546         rc = __smc_buf_create(smc, is_smcd, true);
2547         if (rc && smc->conn.sndbuf_desc) {
2548                 down_write(&smc->conn.lgr->sndbufs_lock);
2549                 smc_lgr_buf_list_del(smc->conn.lgr, false,
2550                                      smc->conn.sndbuf_desc);
2551                 up_write(&smc->conn.lgr->sndbufs_lock);
2552                 smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc);
2553                 smc->conn.sndbuf_desc = NULL;
2554         }
2555         return rc;
2556 }
2557
2558 int smcd_buf_attach(struct smc_sock *smc)
2559 {
2560         struct smc_connection *conn = &smc->conn;
2561         struct smcd_dev *smcd = conn->lgr->smcd;
2562         u64 peer_token = conn->peer_token;
2563         struct smc_buf_desc *buf_desc;
2564         int rc;
2565
2566         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
2567         if (!buf_desc)
2568                 return -ENOMEM;
2569
2570         /* The ghost sndbuf_desc describes the same memory region as
2571          * peer RMB. Its lifecycle is consistent with the connection's
2572          * and it will be freed with the connections instead of the
2573          * link group.
2574          */
2575         rc = smc_ism_attach_dmb(smcd, peer_token, buf_desc);
2576         if (rc)
2577                 goto free;
2578
2579         smc->sk.sk_sndbuf = buf_desc->len;
2580         buf_desc->cpu_addr =
2581                 (u8 *)buf_desc->cpu_addr + sizeof(struct smcd_cdc_msg);
2582         buf_desc->len -= sizeof(struct smcd_cdc_msg);
2583         conn->sndbuf_desc = buf_desc;
2584         conn->sndbuf_desc->used = 1;
2585         atomic_set(&conn->sndbuf_space, conn->sndbuf_desc->len);
2586         return 0;
2587
2588 free:
2589         kfree(buf_desc);
2590         return rc;
2591 }
2592
2593 static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
2594 {
2595         int i;
2596
2597         for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) {
2598                 if (!test_and_set_bit(i, lgr->rtokens_used_mask))
2599                         return i;
2600         }
2601         return -ENOSPC;
2602 }
2603
2604 static int smc_rtoken_find_by_link(struct smc_link_group *lgr, int lnk_idx,
2605                                    u32 rkey)
2606 {
2607         int i;
2608
2609         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2610                 if (test_bit(i, lgr->rtokens_used_mask) &&
2611                     lgr->rtokens[i][lnk_idx].rkey == rkey)
2612                         return i;
2613         }
2614         return -ENOENT;
2615 }
2616
2617 /* set rtoken for a new link to an existing rmb */
2618 void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
2619                     __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey)
2620 {
2621         int rtok_idx;
2622
2623         rtok_idx = smc_rtoken_find_by_link(lgr, link_idx, ntohl(nw_rkey_known));
2624         if (rtok_idx == -ENOENT)
2625                 return;
2626         lgr->rtokens[rtok_idx][link_idx_new].rkey = ntohl(nw_rkey);
2627         lgr->rtokens[rtok_idx][link_idx_new].dma_addr = be64_to_cpu(nw_vaddr);
2628 }
2629
2630 /* set rtoken for a new link whose link_id is given */
2631 void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
2632                      __be64 nw_vaddr, __be32 nw_rkey)
2633 {
2634         u64 dma_addr = be64_to_cpu(nw_vaddr);
2635         u32 rkey = ntohl(nw_rkey);
2636         bool found = false;
2637         int link_idx;
2638
2639         for (link_idx = 0; link_idx < SMC_LINKS_PER_LGR_MAX; link_idx++) {
2640                 if (lgr->lnk[link_idx].link_id == link_id) {
2641                         found = true;
2642                         break;
2643                 }
2644         }
2645         if (!found)
2646                 return;
2647         lgr->rtokens[rtok_idx][link_idx].rkey = rkey;
2648         lgr->rtokens[rtok_idx][link_idx].dma_addr = dma_addr;
2649 }
2650
2651 /* add a new rtoken from peer */
2652 int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey)
2653 {
2654         struct smc_link_group *lgr = smc_get_lgr(lnk);
2655         u64 dma_addr = be64_to_cpu(nw_vaddr);
2656         u32 rkey = ntohl(nw_rkey);
2657         int i;
2658
2659         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2660                 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2661                     lgr->rtokens[i][lnk->link_idx].dma_addr == dma_addr &&
2662                     test_bit(i, lgr->rtokens_used_mask)) {
2663                         /* already in list */
2664                         return i;
2665                 }
2666         }
2667         i = smc_rmb_reserve_rtoken_idx(lgr);
2668         if (i < 0)
2669                 return i;
2670         lgr->rtokens[i][lnk->link_idx].rkey = rkey;
2671         lgr->rtokens[i][lnk->link_idx].dma_addr = dma_addr;
2672         return i;
2673 }
2674
2675 /* delete an rtoken from all links */
2676 int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey)
2677 {
2678         struct smc_link_group *lgr = smc_get_lgr(lnk);
2679         u32 rkey = ntohl(nw_rkey);
2680         int i, j;
2681
2682         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2683                 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2684                     test_bit(i, lgr->rtokens_used_mask)) {
2685                         for (j = 0; j < SMC_LINKS_PER_LGR_MAX; j++) {
2686                                 lgr->rtokens[i][j].rkey = 0;
2687                                 lgr->rtokens[i][j].dma_addr = 0;
2688                         }
2689                         clear_bit(i, lgr->rtokens_used_mask);
2690                         return 0;
2691                 }
2692         }
2693         return -ENOENT;
2694 }
2695
2696 /* save rkey and dma_addr received from peer during clc handshake */
2697 int smc_rmb_rtoken_handling(struct smc_connection *conn,
2698                             struct smc_link *lnk,
2699                             struct smc_clc_msg_accept_confirm *clc)
2700 {
2701         conn->rtoken_idx = smc_rtoken_add(lnk, clc->r0.rmb_dma_addr,
2702                                           clc->r0.rmb_rkey);
2703         if (conn->rtoken_idx < 0)
2704                 return conn->rtoken_idx;
2705         return 0;
2706 }
2707
2708 static void smc_core_going_away(void)
2709 {
2710         struct smc_ib_device *smcibdev;
2711         struct smcd_dev *smcd;
2712
2713         mutex_lock(&smc_ib_devices.mutex);
2714         list_for_each_entry(smcibdev, &smc_ib_devices.list, list) {
2715                 int i;
2716
2717                 for (i = 0; i < SMC_MAX_PORTS; i++)
2718                         set_bit(i, smcibdev->ports_going_away);
2719         }
2720         mutex_unlock(&smc_ib_devices.mutex);
2721
2722         mutex_lock(&smcd_dev_list.mutex);
2723         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2724                 smcd->going_away = 1;
2725         }
2726         mutex_unlock(&smcd_dev_list.mutex);
2727 }
2728
2729 /* Clean up all SMC link groups */
2730 static void smc_lgrs_shutdown(void)
2731 {
2732         struct smcd_dev *smcd;
2733
2734         smc_core_going_away();
2735
2736         smc_smcr_terminate_all(NULL);
2737
2738         mutex_lock(&smcd_dev_list.mutex);
2739         list_for_each_entry(smcd, &smcd_dev_list.list, list)
2740                 smc_smcd_terminate_all(smcd);
2741         mutex_unlock(&smcd_dev_list.mutex);
2742 }
2743
2744 static int smc_core_reboot_event(struct notifier_block *this,
2745                                  unsigned long event, void *ptr)
2746 {
2747         smc_lgrs_shutdown();
2748         smc_ib_unregister_client();
2749         smc_ism_exit();
2750         return 0;
2751 }
2752
2753 static struct notifier_block smc_reboot_notifier = {
2754         .notifier_call = smc_core_reboot_event,
2755 };
2756
2757 int __init smc_core_init(void)
2758 {
2759         return register_reboot_notifier(&smc_reboot_notifier);
2760 }
2761
2762 /* Called (from smc_exit) when module is removed */
2763 void smc_core_exit(void)
2764 {
2765         unregister_reboot_notifier(&smc_reboot_notifier);
2766         smc_lgrs_shutdown();
2767 }