net/smc/smc_core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
   4  *
   5  *  Basic Transport Functions exploiting Infiniband API
   6  *
   7  *  Copyright IBM Corp. 2016
   8  *
   9  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
  10  */
  11
  12 #include <linux/socket.h>
  13 #include <linux/if_vlan.h>
  14 #include <linux/random.h>
  15 #include <linux/workqueue.h>
  16 #include <linux/wait.h>
  17 #include <linux/reboot.h>
  18 #include <linux/mutex.h>
  19 #include <linux/list.h>
  20 #include <linux/smc.h>
  21 #include <net/tcp.h>
  22 #include <net/sock.h>
  23 #include <rdma/ib_verbs.h>
  24 #include <rdma/ib_cache.h>
  25
  26 #include "smc.h"
  27 #include "smc_clc.h"
  28 #include "smc_core.h"
  29 #include "smc_ib.h"
  30 #include "smc_wr.h"
  31 #include "smc_llc.h"
  32 #include "smc_cdc.h"
  33 #include "smc_close.h"
  34 #include "smc_ism.h"
  35 #include "smc_netlink.h"
  36 #include "smc_stats.h"
  37 #include "smc_tracepoint.h"
  38
  39 #define SMC_LGR_NUM_INCR                256
  40 #define SMC_LGR_FREE_DELAY_SERV         (600 * HZ)
  41 #define SMC_LGR_FREE_DELAY_CLNT         (SMC_LGR_FREE_DELAY_SERV + 10 * HZ)
  42
  43 struct smc_lgr_list smc_lgr_list = {    /* established link groups */
  44         .lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
  45         .list = LIST_HEAD_INIT(smc_lgr_list.list),
  46         .num = 0,
  47 };
  48
  49 static atomic_t lgr_cnt = ATOMIC_INIT(0); /* number of existing link groups */
  50 static DECLARE_WAIT_QUEUE_HEAD(lgrs_deleted);
  51
  52 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
  53                          struct smc_buf_desc *buf_desc);
  54 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft);
  55
  56 static void smc_link_down_work(struct work_struct *work);
  57
  58 /* return head of link group list and its lock for a given link group */
  59 static inline struct list_head *smc_lgr_list_head(struct smc_link_group *lgr,
  60                                                   spinlock_t **lgr_lock)
  61 {
  62         if (lgr->is_smcd) {
  63                 *lgr_lock = &lgr->smcd->lgr_lock;
  64                 return &lgr->smcd->lgr_list;
  65         }
  66
  67         *lgr_lock = &smc_lgr_list.lock;
  68         return &smc_lgr_list.list;
  69 }
  70
  71 static void smc_ibdev_cnt_inc(struct smc_link *lnk)
  72 {
  73         atomic_inc(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
  74 }
  75
  76 static void smc_ibdev_cnt_dec(struct smc_link *lnk)
  77 {
  78         atomic_dec(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
  79 }
  80
  81 static void smc_lgr_schedule_free_work(struct smc_link_group *lgr)
  82 {
  83         /* client link group creation always follows the server link group
  84          * creation. For client use a somewhat higher removal delay time,
  85          * otherwise there is a risk of out-of-sync link groups.
  86          */
  87         if (!lgr->freeing) {
  88                 mod_delayed_work(system_wq, &lgr->free_work,
  89                                  (!lgr->is_smcd && lgr->role == SMC_CLNT) ?
  90                                                 SMC_LGR_FREE_DELAY_CLNT :
  91                                                 SMC_LGR_FREE_DELAY_SERV);
  92         }
  93 }
  94
  95 /* Register connection's alert token in our lookup structure.
  96  * To use rbtrees we have to implement our own insert core.
  97  * Requires @conns_lock
  98  * @smc         connection to register
  99  * Returns 0 on success, != otherwise.
 100  */
 101 static void smc_lgr_add_alert_token(struct smc_connection *conn)
 102 {
 103         struct rb_node **link, *parent = NULL;
 104         u32 token = conn->alert_token_local;
 105
 106         link = &conn->lgr->conns_all.rb_node;
 107         while (*link) {
 108                 struct smc_connection *cur = rb_entry(*link,
 109                                         struct smc_connection, alert_node);
 110
 111                 parent = *link;
 112                 if (cur->alert_token_local > token)
 113                         link = &parent->rb_left;
 114                 else
 115                         link = &parent->rb_right;
 116         }
 117         /* Put the new node there */
 118         rb_link_node(&conn->alert_node, parent, link);
 119         rb_insert_color(&conn->alert_node, &conn->lgr->conns_all);
 120 }
 121
 122 /* assign an SMC-R link to the connection */
 123 static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first)
 124 {
 125         enum smc_link_state expected = first ? SMC_LNK_ACTIVATING :
 126                                        SMC_LNK_ACTIVE;
 127         int i, j;
 128
 129         /* do link balancing */
 130         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 131                 struct smc_link *lnk = &conn->lgr->lnk[i];
 132
 133                 if (lnk->state != expected || lnk->link_is_asym)
 134                         continue;
 135                 if (conn->lgr->role == SMC_CLNT) {
 136                         conn->lnk = lnk; /* temporary, SMC server assigns link*/
 137                         break;
 138                 }
 139                 if (conn->lgr->conns_num % 2) {
 140                         for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) {
 141                                 struct smc_link *lnk2;
 142
 143                                 lnk2 = &conn->lgr->lnk[j];
 144                                 if (lnk2->state == expected &&
 145                                     !lnk2->link_is_asym) {
 146                                         conn->lnk = lnk2;
 147                                         break;
 148                                 }
 149                         }
 150                 }
 151                 if (!conn->lnk)
 152                         conn->lnk = lnk;
 153                 break;
 154         }
 155         if (!conn->lnk)
 156                 return SMC_CLC_DECL_NOACTLINK;
 157         atomic_inc(&conn->lnk->conn_cnt);
 158         return 0;
 159 }
 160
 161 /* Register connection in link group by assigning an alert token
 162  * registered in a search tree.
 163  * Requires @conns_lock
 164  * Note that '0' is a reserved value and not assigned.
 165  */
 166 static int smc_lgr_register_conn(struct smc_connection *conn, bool first)
 167 {
 168         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 169         static atomic_t nexttoken = ATOMIC_INIT(0);
 170         int rc;
 171
 172         if (!conn->lgr->is_smcd) {
 173                 rc = smcr_lgr_conn_assign_link(conn, first);
 174                 if (rc) {
 175                         conn->lgr = NULL;
 176                         return rc;
 177                 }
 178         }
 179         /* find a new alert_token_local value not yet used by some connection
 180          * in this link group
 181          */
 182         sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */
 183         while (!conn->alert_token_local) {
 184                 conn->alert_token_local = atomic_inc_return(&nexttoken);
 185                 if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr))
 186                         conn->alert_token_local = 0;
 187         }
 188         smc_lgr_add_alert_token(conn);
 189         conn->lgr->conns_num++;
 190         return 0;
 191 }
 192
 193 /* Unregister connection and reset the alert token of the given connection<
 194  */
 195 static void __smc_lgr_unregister_conn(struct smc_connection *conn)
 196 {
 197         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 198         struct smc_link_group *lgr = conn->lgr;
 199
 200         rb_erase(&conn->alert_node, &lgr->conns_all);
 201         if (conn->lnk)
 202                 atomic_dec(&conn->lnk->conn_cnt);
 203         lgr->conns_num--;
 204         conn->alert_token_local = 0;
 205         sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
 206 }
 207
 208 /* Unregister connection from lgr
 209  */
 210 static void smc_lgr_unregister_conn(struct smc_connection *conn)
 211 {
 212         struct smc_link_group *lgr = conn->lgr;
 213
 214         if (!smc_conn_lgr_valid(conn))
 215                 return;
 216         write_lock_bh(&lgr->conns_lock);
 217         if (conn->alert_token_local) {
 218                 __smc_lgr_unregister_conn(conn);
 219         }
 220         write_unlock_bh(&lgr->conns_lock);
 221 }
 222
 223 int smc_nl_get_sys_info(struct sk_buff *skb, struct netlink_callback *cb)
 224 {
 225         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 226         char hostname[SMC_MAX_HOSTNAME_LEN + 1];
 227         char smc_seid[SMC_MAX_EID_LEN + 1];
 228         struct nlattr *attrs;
 229         u8 *seid = NULL;
 230         u8 *host = NULL;
 231         void *nlh;
 232
 233         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 234                           &smc_gen_nl_family, NLM_F_MULTI,
 235                           SMC_NETLINK_GET_SYS_INFO);
 236         if (!nlh)
 237                 goto errmsg;
 238         if (cb_ctx->pos[0])
 239                 goto errout;
 240         attrs = nla_nest_start(skb, SMC_GEN_SYS_INFO);
 241         if (!attrs)
 242                 goto errout;
 243         if (nla_put_u8(skb, SMC_NLA_SYS_VER, SMC_V2))
 244                 goto errattr;
 245         if (nla_put_u8(skb, SMC_NLA_SYS_REL, SMC_RELEASE))
 246                 goto errattr;
 247         if (nla_put_u8(skb, SMC_NLA_SYS_IS_ISM_V2, smc_ism_is_v2_capable()))
 248                 goto errattr;
 249         if (nla_put_u8(skb, SMC_NLA_SYS_IS_SMCR_V2, true))
 250                 goto errattr;
 251         smc_clc_get_hostname(&host);
 252         if (host) {
 253                 memcpy(hostname, host, SMC_MAX_HOSTNAME_LEN);
 254                 hostname[SMC_MAX_HOSTNAME_LEN] = 0;
 255                 if (nla_put_string(skb, SMC_NLA_SYS_LOCAL_HOST, hostname))
 256                         goto errattr;
 257         }
 258         if (smc_ism_is_v2_capable()) {
 259                 smc_ism_get_system_eid(&seid);
 260                 memcpy(smc_seid, seid, SMC_MAX_EID_LEN);
 261                 smc_seid[SMC_MAX_EID_LEN] = 0;
 262                 if (nla_put_string(skb, SMC_NLA_SYS_SEID, smc_seid))
 263                         goto errattr;
 264         }
 265         nla_nest_end(skb, attrs);
 266         genlmsg_end(skb, nlh);
 267         cb_ctx->pos[0] = 1;
 268         return skb->len;
 269
 270 errattr:
 271         nla_nest_cancel(skb, attrs);
 272 errout:
 273         genlmsg_cancel(skb, nlh);
 274 errmsg:
 275         return skb->len;
 276 }
 277
 278 /* Fill SMC_NLA_LGR_D_V2_COMMON/SMC_NLA_LGR_R_V2_COMMON nested attributes */
 279 static int smc_nl_fill_lgr_v2_common(struct smc_link_group *lgr,
 280                                      struct sk_buff *skb,
 281                                      struct netlink_callback *cb,
 282                                      struct nlattr *v2_attrs)
 283 {
 284         char smc_host[SMC_MAX_HOSTNAME_LEN + 1];
 285         char smc_eid[SMC_MAX_EID_LEN + 1];
 286
 287         if (nla_put_u8(skb, SMC_NLA_LGR_V2_VER, lgr->smc_version))
 288                 goto errv2attr;
 289         if (nla_put_u8(skb, SMC_NLA_LGR_V2_REL, lgr->peer_smc_release))
 290                 goto errv2attr;
 291         if (nla_put_u8(skb, SMC_NLA_LGR_V2_OS, lgr->peer_os))
 292                 goto errv2attr;
 293         memcpy(smc_host, lgr->peer_hostname, SMC_MAX_HOSTNAME_LEN);
 294         smc_host[SMC_MAX_HOSTNAME_LEN] = 0;
 295         if (nla_put_string(skb, SMC_NLA_LGR_V2_PEER_HOST, smc_host))
 296                 goto errv2attr;
 297         memcpy(smc_eid, lgr->negotiated_eid, SMC_MAX_EID_LEN);
 298         smc_eid[SMC_MAX_EID_LEN] = 0;
 299         if (nla_put_string(skb, SMC_NLA_LGR_V2_NEG_EID, smc_eid))
 300                 goto errv2attr;
 301
 302         nla_nest_end(skb, v2_attrs);
 303         return 0;
 304
 305 errv2attr:
 306         nla_nest_cancel(skb, v2_attrs);
 307         return -EMSGSIZE;
 308 }
 309
 310 static int smc_nl_fill_smcr_lgr_v2(struct smc_link_group *lgr,
 311                                    struct sk_buff *skb,
 312                                    struct netlink_callback *cb)
 313 {
 314         struct nlattr *v2_attrs;
 315
 316         v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2);
 317         if (!v2_attrs)
 318                 goto errattr;
 319         if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_DIRECT, !lgr->uses_gateway))
 320                 goto errv2attr;
 321
 322         nla_nest_end(skb, v2_attrs);
 323         return 0;
 324
 325 errv2attr:
 326         nla_nest_cancel(skb, v2_attrs);
 327 errattr:
 328         return -EMSGSIZE;
 329 }
 330
 331 static int smc_nl_fill_lgr(struct smc_link_group *lgr,
 332                            struct sk_buff *skb,
 333                            struct netlink_callback *cb)
 334 {
 335         char smc_target[SMC_MAX_PNETID_LEN + 1];
 336         struct nlattr *attrs, *v2_attrs;
 337
 338         attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCR);
 339         if (!attrs)
 340                 goto errout;
 341
 342         if (nla_put_u32(skb, SMC_NLA_LGR_R_ID, *((u32 *)&lgr->id)))
 343                 goto errattr;
 344         if (nla_put_u32(skb, SMC_NLA_LGR_R_CONNS_NUM, lgr->conns_num))
 345                 goto errattr;
 346         if (nla_put_u8(skb, SMC_NLA_LGR_R_ROLE, lgr->role))
 347                 goto errattr;
 348         if (nla_put_u8(skb, SMC_NLA_LGR_R_TYPE, lgr->type))
 349                 goto errattr;
 350         if (nla_put_u8(skb, SMC_NLA_LGR_R_BUF_TYPE, lgr->buf_type))
 351                 goto errattr;
 352         if (nla_put_u8(skb, SMC_NLA_LGR_R_VLAN_ID, lgr->vlan_id))
 353                 goto errattr;
 354         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_R_NET_COOKIE,
 355                               lgr->net->net_cookie, SMC_NLA_LGR_R_PAD))
 356                 goto errattr;
 357         memcpy(smc_target, lgr->pnet_id, SMC_MAX_PNETID_LEN);
 358         smc_target[SMC_MAX_PNETID_LEN] = 0;
 359         if (nla_put_string(skb, SMC_NLA_LGR_R_PNETID, smc_target))
 360                 goto errattr;
 361         if (lgr->smc_version > SMC_V1) {
 362                 v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2_COMMON);
 363                 if (!v2_attrs)
 364                         goto errattr;
 365                 if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
 366                         goto errattr;
 367                 if (smc_nl_fill_smcr_lgr_v2(lgr, skb, cb))
 368                         goto errattr;
 369         }
 370
 371         nla_nest_end(skb, attrs);
 372         return 0;
 373 errattr:
 374         nla_nest_cancel(skb, attrs);
 375 errout:
 376         return -EMSGSIZE;
 377 }
 378
 379 static int smc_nl_fill_lgr_link(struct smc_link_group *lgr,
 380                                 struct smc_link *link,
 381                                 struct sk_buff *skb,
 382                                 struct netlink_callback *cb)
 383 {
 384         char smc_ibname[IB_DEVICE_NAME_MAX];
 385         u8 smc_gid_target[41];
 386         struct nlattr *attrs;
 387         u32 link_uid = 0;
 388         void *nlh;
 389
 390         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 391                           &smc_gen_nl_family, NLM_F_MULTI,
 392                           SMC_NETLINK_GET_LINK_SMCR);
 393         if (!nlh)
 394                 goto errmsg;
 395
 396         attrs = nla_nest_start(skb, SMC_GEN_LINK_SMCR);
 397         if (!attrs)
 398                 goto errout;
 399
 400         if (nla_put_u8(skb, SMC_NLA_LINK_ID, link->link_id))
 401                 goto errattr;
 402         if (nla_put_u32(skb, SMC_NLA_LINK_STATE, link->state))
 403                 goto errattr;
 404         if (nla_put_u32(skb, SMC_NLA_LINK_CONN_CNT,
 405                         atomic_read(&link->conn_cnt)))
 406                 goto errattr;
 407         if (nla_put_u8(skb, SMC_NLA_LINK_IB_PORT, link->ibport))
 408                 goto errattr;
 409         if (nla_put_u32(skb, SMC_NLA_LINK_NET_DEV, link->ndev_ifidx))
 410                 goto errattr;
 411         snprintf(smc_ibname, sizeof(smc_ibname), "%s", link->ibname);
 412         if (nla_put_string(skb, SMC_NLA_LINK_IB_DEV, smc_ibname))
 413                 goto errattr;
 414         memcpy(&link_uid, link->link_uid, sizeof(link_uid));
 415         if (nla_put_u32(skb, SMC_NLA_LINK_UID, link_uid))
 416                 goto errattr;
 417         memcpy(&link_uid, link->peer_link_uid, sizeof(link_uid));
 418         if (nla_put_u32(skb, SMC_NLA_LINK_PEER_UID, link_uid))
 419                 goto errattr;
 420         memset(smc_gid_target, 0, sizeof(smc_gid_target));
 421         smc_gid_be16_convert(smc_gid_target, link->gid);
 422         if (nla_put_string(skb, SMC_NLA_LINK_GID, smc_gid_target))
 423                 goto errattr;
 424         memset(smc_gid_target, 0, sizeof(smc_gid_target));
 425         smc_gid_be16_convert(smc_gid_target, link->peer_gid);
 426         if (nla_put_string(skb, SMC_NLA_LINK_PEER_GID, smc_gid_target))
 427                 goto errattr;
 428
 429         nla_nest_end(skb, attrs);
 430         genlmsg_end(skb, nlh);
 431         return 0;
 432 errattr:
 433         nla_nest_cancel(skb, attrs);
 434 errout:
 435         genlmsg_cancel(skb, nlh);
 436 errmsg:
 437         return -EMSGSIZE;
 438 }
 439
 440 static int smc_nl_handle_lgr(struct smc_link_group *lgr,
 441                              struct sk_buff *skb,
 442                              struct netlink_callback *cb,
 443                              bool list_links)
 444 {
 445         void *nlh;
 446         int i;
 447
 448         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 449                           &smc_gen_nl_family, NLM_F_MULTI,
 450                           SMC_NETLINK_GET_LGR_SMCR);
 451         if (!nlh)
 452                 goto errmsg;
 453         if (smc_nl_fill_lgr(lgr, skb, cb))
 454                 goto errout;
 455
 456         genlmsg_end(skb, nlh);
 457         if (!list_links)
 458                 goto out;
 459         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 460                 if (!smc_link_usable(&lgr->lnk[i]))
 461                         continue;
 462                 if (smc_nl_fill_lgr_link(lgr, &lgr->lnk[i], skb, cb))
 463                         goto errout;
 464         }
 465 out:
 466         return 0;
 467
 468 errout:
 469         genlmsg_cancel(skb, nlh);
 470 errmsg:
 471         return -EMSGSIZE;
 472 }
 473
 474 static void smc_nl_fill_lgr_list(struct smc_lgr_list *smc_lgr,
 475                                  struct sk_buff *skb,
 476                                  struct netlink_callback *cb,
 477                                  bool list_links)
 478 {
 479         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 480         struct smc_link_group *lgr;
 481         int snum = cb_ctx->pos[0];
 482         int num = 0;
 483
 484         spin_lock_bh(&smc_lgr->lock);
 485         list_for_each_entry(lgr, &smc_lgr->list, list) {
 486                 if (num < snum)
 487                         goto next;
 488                 if (smc_nl_handle_lgr(lgr, skb, cb, list_links))
 489                         goto errout;
 490 next:
 491                 num++;
 492         }
 493 errout:
 494         spin_unlock_bh(&smc_lgr->lock);
 495         cb_ctx->pos[0] = num;
 496 }
 497
 498 static int smc_nl_fill_smcd_lgr(struct smc_link_group *lgr,
 499                                 struct sk_buff *skb,
 500                                 struct netlink_callback *cb)
 501 {
 502         char smc_pnet[SMC_MAX_PNETID_LEN + 1];
 503         struct nlattr *attrs;
 504         void *nlh;
 505
 506         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 507                           &smc_gen_nl_family, NLM_F_MULTI,
 508                           SMC_NETLINK_GET_LGR_SMCD);
 509         if (!nlh)
 510                 goto errmsg;
 511
 512         attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCD);
 513         if (!attrs)
 514                 goto errout;
 515
 516         if (nla_put_u32(skb, SMC_NLA_LGR_D_ID, *((u32 *)&lgr->id)))
 517                 goto errattr;
 518         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_GID, lgr->smcd->local_gid,
 519                               SMC_NLA_LGR_D_PAD))
 520                 goto errattr;
 521         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_GID, lgr->peer_gid,
 522                               SMC_NLA_LGR_D_PAD))
 523                 goto errattr;
 524         if (nla_put_u8(skb, SMC_NLA_LGR_D_VLAN_ID, lgr->vlan_id))
 525                 goto errattr;
 526         if (nla_put_u32(skb, SMC_NLA_LGR_D_CONNS_NUM, lgr->conns_num))
 527                 goto errattr;
 528         if (nla_put_u32(skb, SMC_NLA_LGR_D_CHID, smc_ism_get_chid(lgr->smcd)))
 529                 goto errattr;
 530         memcpy(smc_pnet, lgr->smcd->pnetid, SMC_MAX_PNETID_LEN);
 531         smc_pnet[SMC_MAX_PNETID_LEN] = 0;
 532         if (nla_put_string(skb, SMC_NLA_LGR_D_PNETID, smc_pnet))
 533                 goto errattr;
 534         if (lgr->smc_version > SMC_V1) {
 535                 struct nlattr *v2_attrs;
 536
 537                 v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_D_V2_COMMON);
 538                 if (!v2_attrs)
 539                         goto errattr;
 540                 if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
 541                         goto errattr;
 542         }
 543         nla_nest_end(skb, attrs);
 544         genlmsg_end(skb, nlh);
 545         return 0;
 546
 547 errattr:
 548         nla_nest_cancel(skb, attrs);
 549 errout:
 550         genlmsg_cancel(skb, nlh);
 551 errmsg:
 552         return -EMSGSIZE;
 553 }
 554
 555 static int smc_nl_handle_smcd_lgr(struct smcd_dev *dev,
 556                                   struct sk_buff *skb,
 557                                   struct netlink_callback *cb)
 558 {
 559         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 560         struct smc_link_group *lgr;
 561         int snum = cb_ctx->pos[1];
 562         int rc = 0, num = 0;
 563
 564         spin_lock_bh(&dev->lgr_lock);
 565         list_for_each_entry(lgr, &dev->lgr_list, list) {
 566                 if (!lgr->is_smcd)
 567                         continue;
 568                 if (num < snum)
 569                         goto next;
 570                 rc = smc_nl_fill_smcd_lgr(lgr, skb, cb);
 571                 if (rc)
 572                         goto errout;
 573 next:
 574                 num++;
 575         }
 576 errout:
 577         spin_unlock_bh(&dev->lgr_lock);
 578         cb_ctx->pos[1] = num;
 579         return rc;
 580 }
 581
 582 static int smc_nl_fill_smcd_dev(struct smcd_dev_list *dev_list,
 583                                 struct sk_buff *skb,
 584                                 struct netlink_callback *cb)
 585 {
 586         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 587         struct smcd_dev *smcd_dev;
 588         int snum = cb_ctx->pos[0];
 589         int rc = 0, num = 0;
 590
 591         mutex_lock(&dev_list->mutex);
 592         list_for_each_entry(smcd_dev, &dev_list->list, list) {
 593                 if (list_empty(&smcd_dev->lgr_list))
 594                         continue;
 595                 if (num < snum)
 596                         goto next;
 597                 rc = smc_nl_handle_smcd_lgr(smcd_dev, skb, cb);
 598                 if (rc)
 599                         goto errout;
 600 next:
 601                 num++;
 602         }
 603 errout:
 604         mutex_unlock(&dev_list->mutex);
 605         cb_ctx->pos[0] = num;
 606         return rc;
 607 }
 608
 609 int smcr_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
 610 {
 611         bool list_links = false;
 612
 613         smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
 614         return skb->len;
 615 }
 616
 617 int smcr_nl_get_link(struct sk_buff *skb, struct netlink_callback *cb)
 618 {
 619         bool list_links = true;
 620
 621         smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
 622         return skb->len;
 623 }
 624
 625 int smcd_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
 626 {
 627         smc_nl_fill_smcd_dev(&smcd_dev_list, skb, cb);
 628         return skb->len;
 629 }
 630
 631 void smc_lgr_cleanup_early(struct smc_link_group *lgr)
 632 {
 633         spinlock_t *lgr_lock;
 634
 635         if (!lgr)
 636                 return;
 637
 638         smc_lgr_list_head(lgr, &lgr_lock);
 639         spin_lock_bh(lgr_lock);
 640         /* do not use this link group for new connections */
 641         if (!list_empty(&lgr->list))
 642                 list_del_init(&lgr->list);
 643         spin_unlock_bh(lgr_lock);
 644         __smc_lgr_terminate(lgr, true);
 645 }
 646
 647 static void smcr_lgr_link_deactivate_all(struct smc_link_group *lgr)
 648 {
 649         int i;
 650
 651         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 652                 struct smc_link *lnk = &lgr->lnk[i];
 653
 654                 if (smc_link_sendable(lnk))
 655                         lnk->state = SMC_LNK_INACTIVE;
 656         }
 657         wake_up_all(&lgr->llc_msg_waiter);
 658         wake_up_all(&lgr->llc_flow_waiter);
 659 }
 660
 661 static void smc_lgr_free(struct smc_link_group *lgr);
 662
 663 static void smc_lgr_free_work(struct work_struct *work)
 664 {
 665         struct smc_link_group *lgr = container_of(to_delayed_work(work),
 666                                                   struct smc_link_group,
 667                                                   free_work);
 668         spinlock_t *lgr_lock;
 669         bool conns;
 670
 671         smc_lgr_list_head(lgr, &lgr_lock);
 672         spin_lock_bh(lgr_lock);
 673         if (lgr->freeing) {
 674                 spin_unlock_bh(lgr_lock);
 675                 return;
 676         }
 677         read_lock_bh(&lgr->conns_lock);
 678         conns = RB_EMPTY_ROOT(&lgr->conns_all);
 679         read_unlock_bh(&lgr->conns_lock);
 680         if (!conns) { /* number of lgr connections is no longer zero */
 681                 spin_unlock_bh(lgr_lock);
 682                 return;
 683         }
 684         list_del_init(&lgr->list); /* remove from smc_lgr_list */
 685         lgr->freeing = 1; /* this instance does the freeing, no new schedule */
 686         spin_unlock_bh(lgr_lock);
 687         cancel_delayed_work(&lgr->free_work);
 688
 689         if (!lgr->is_smcd && !lgr->terminating)
 690                 smc_llc_send_link_delete_all(lgr, true,
 691                                              SMC_LLC_DEL_PROG_INIT_TERM);
 692         if (lgr->is_smcd && !lgr->terminating)
 693                 smc_ism_signal_shutdown(lgr);
 694         if (!lgr->is_smcd)
 695                 smcr_lgr_link_deactivate_all(lgr);
 696         smc_lgr_free(lgr);
 697 }
 698
 699 static void smc_lgr_terminate_work(struct work_struct *work)
 700 {
 701         struct smc_link_group *lgr = container_of(work, struct smc_link_group,
 702                                                   terminate_work);
 703
 704         __smc_lgr_terminate(lgr, true);
 705 }
 706
 707 /* return next unique link id for the lgr */
 708 static u8 smcr_next_link_id(struct smc_link_group *lgr)
 709 {
 710         u8 link_id;
 711         int i;
 712
 713         while (1) {
 714 again:
 715                 link_id = ++lgr->next_link_id;
 716                 if (!link_id)   /* skip zero as link_id */
 717                         link_id = ++lgr->next_link_id;
 718                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 719                         if (smc_link_usable(&lgr->lnk[i]) &&
 720                             lgr->lnk[i].link_id == link_id)
 721                                 goto again;
 722                 }
 723                 break;
 724         }
 725         return link_id;
 726 }
 727
 728 static void smcr_copy_dev_info_to_link(struct smc_link *link)
 729 {
 730         struct smc_ib_device *smcibdev = link->smcibdev;
 731
 732         snprintf(link->ibname, sizeof(link->ibname), "%s",
 733                  smcibdev->ibdev->name);
 734         link->ndev_ifidx = smcibdev->ndev_ifidx[link->ibport - 1];
 735 }
 736
 737 int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
 738                    u8 link_idx, struct smc_init_info *ini)
 739 {
 740         struct smc_ib_device *smcibdev;
 741         u8 rndvec[3];
 742         int rc;
 743
 744         if (lgr->smc_version == SMC_V2) {
 745                 lnk->smcibdev = ini->smcrv2.ib_dev_v2;
 746                 lnk->ibport = ini->smcrv2.ib_port_v2;
 747         } else {
 748                 lnk->smcibdev = ini->ib_dev;
 749                 lnk->ibport = ini->ib_port;
 750         }
 751         get_device(&lnk->smcibdev->ibdev->dev);
 752         atomic_inc(&lnk->smcibdev->lnk_cnt);
 753         refcount_set(&lnk->refcnt, 1); /* link refcnt is set to 1 */
 754         lnk->clearing = 0;
 755         lnk->path_mtu = lnk->smcibdev->pattr[lnk->ibport - 1].active_mtu;
 756         lnk->link_id = smcr_next_link_id(lgr);
 757         lnk->lgr = lgr;
 758         smc_lgr_hold(lgr); /* lgr_put in smcr_link_clear() */
 759         lnk->link_idx = link_idx;
 760         lnk->wr_rx_id_compl = 0;
 761         smc_ibdev_cnt_inc(lnk);
 762         smcr_copy_dev_info_to_link(lnk);
 763         atomic_set(&lnk->conn_cnt, 0);
 764         smc_llc_link_set_uid(lnk);
 765         INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
 766         if (!lnk->smcibdev->initialized) {
 767                 rc = (int)smc_ib_setup_per_ibdev(lnk->smcibdev);
 768                 if (rc)
 769                         goto out;
 770         }
 771         get_random_bytes(rndvec, sizeof(rndvec));
 772         lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) +
 773                 (rndvec[2] << 16);
 774         rc = smc_ib_determine_gid(lnk->smcibdev, lnk->ibport,
 775                                   ini->vlan_id, lnk->gid, &lnk->sgid_index,
 776                                   lgr->smc_version == SMC_V2 ?
 777                                                   &ini->smcrv2 : NULL);
 778         if (rc)
 779                 goto out;
 780         rc = smc_llc_link_init(lnk);
 781         if (rc)
 782                 goto out;
 783         rc = smc_wr_alloc_link_mem(lnk);
 784         if (rc)
 785                 goto clear_llc_lnk;
 786         rc = smc_ib_create_protection_domain(lnk);
 787         if (rc)
 788                 goto free_link_mem;
 789         rc = smc_ib_create_queue_pair(lnk);
 790         if (rc)
 791                 goto dealloc_pd;
 792         rc = smc_wr_create_link(lnk);
 793         if (rc)
 794                 goto destroy_qp;
 795         lnk->state = SMC_LNK_ACTIVATING;
 796         return 0;
 797
 798 destroy_qp:
 799         smc_ib_destroy_queue_pair(lnk);
 800 dealloc_pd:
 801         smc_ib_dealloc_protection_domain(lnk);
 802 free_link_mem:
 803         smc_wr_free_link_mem(lnk);
 804 clear_llc_lnk:
 805         smc_llc_link_clear(lnk, false);
 806 out:
 807         smc_ibdev_cnt_dec(lnk);
 808         put_device(&lnk->smcibdev->ibdev->dev);
 809         smcibdev = lnk->smcibdev;
 810         memset(lnk, 0, sizeof(struct smc_link));
 811         lnk->state = SMC_LNK_UNUSED;
 812         if (!atomic_dec_return(&smcibdev->lnk_cnt))
 813                 wake_up(&smcibdev->lnks_deleted);
 814         smc_lgr_put(lgr); /* lgr_hold above */
 815         return rc;
 816 }
 817
 818 /* create a new SMC link group */
 819 static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
 820 {
 821         struct smc_link_group *lgr;
 822         struct list_head *lgr_list;
 823         struct smc_link *lnk;
 824         spinlock_t *lgr_lock;
 825         u8 link_idx;
 826         int rc = 0;
 827         int i;
 828
 829         if (ini->is_smcd && ini->vlan_id) {
 830                 if (smc_ism_get_vlan(ini->ism_dev[ini->ism_selected],
 831                                      ini->vlan_id)) {
 832                         rc = SMC_CLC_DECL_ISMVLANERR;
 833                         goto out;
 834                 }
 835         }
 836
 837         lgr = kzalloc(sizeof(*lgr), GFP_KERNEL);
 838         if (!lgr) {
 839                 rc = SMC_CLC_DECL_MEM;
 840                 goto ism_put_vlan;
 841         }
 842         lgr->tx_wq = alloc_workqueue("smc_tx_wq-%*phN", 0, 0,
 843                                      SMC_LGR_ID_SIZE, &lgr->id);
 844         if (!lgr->tx_wq) {
 845                 rc = -ENOMEM;
 846                 goto free_lgr;
 847         }
 848         lgr->is_smcd = ini->is_smcd;
 849         lgr->sync_err = 0;
 850         lgr->terminating = 0;
 851         lgr->freeing = 0;
 852         lgr->vlan_id = ini->vlan_id;
 853         refcount_set(&lgr->refcnt, 1); /* set lgr refcnt to 1 */
 854         mutex_init(&lgr->sndbufs_lock);
 855         mutex_init(&lgr->rmbs_lock);
 856         rwlock_init(&lgr->conns_lock);
 857         for (i = 0; i < SMC_RMBE_SIZES; i++) {
 858                 INIT_LIST_HEAD(&lgr->sndbufs[i]);
 859                 INIT_LIST_HEAD(&lgr->rmbs[i]);
 860         }
 861         lgr->next_link_id = 0;
 862         smc_lgr_list.num += SMC_LGR_NUM_INCR;
 863         memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE);
 864         INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
 865         INIT_WORK(&lgr->terminate_work, smc_lgr_terminate_work);
 866         lgr->conns_all = RB_ROOT;
 867         if (ini->is_smcd) {
 868                 /* SMC-D specific settings */
 869                 get_device(&ini->ism_dev[ini->ism_selected]->dev);
 870                 lgr->peer_gid = ini->ism_peer_gid[ini->ism_selected];
 871                 lgr->smcd = ini->ism_dev[ini->ism_selected];
 872                 lgr_list = &ini->ism_dev[ini->ism_selected]->lgr_list;
 873                 lgr_lock = &lgr->smcd->lgr_lock;
 874                 lgr->smc_version = ini->smcd_version;
 875                 lgr->peer_shutdown = 0;
 876                 atomic_inc(&ini->ism_dev[ini->ism_selected]->lgr_cnt);
 877         } else {
 878                 /* SMC-R specific settings */
 879                 struct smc_ib_device *ibdev;
 880                 int ibport;
 881
 882                 lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
 883                 lgr->smc_version = ini->smcr_version;
 884                 memcpy(lgr->peer_systemid, ini->peer_systemid,
 885                        SMC_SYSTEMID_LEN);
 886                 if (lgr->smc_version == SMC_V2) {
 887                         ibdev = ini->smcrv2.ib_dev_v2;
 888                         ibport = ini->smcrv2.ib_port_v2;
 889                         lgr->saddr = ini->smcrv2.saddr;
 890                         lgr->uses_gateway = ini->smcrv2.uses_gateway;
 891                         memcpy(lgr->nexthop_mac, ini->smcrv2.nexthop_mac,
 892                                ETH_ALEN);
 893                 } else {
 894                         ibdev = ini->ib_dev;
 895                         ibport = ini->ib_port;
 896                 }
 897                 memcpy(lgr->pnet_id, ibdev->pnetid[ibport - 1],
 898                        SMC_MAX_PNETID_LEN);
 899                 rc = smc_wr_alloc_lgr_mem(lgr);
 900                 if (rc)
 901                         goto free_wq;
 902                 smc_llc_lgr_init(lgr, smc);
 903
 904                 link_idx = SMC_SINGLE_LINK;
 905                 lnk = &lgr->lnk[link_idx];
 906                 rc = smcr_link_init(lgr, lnk, link_idx, ini);
 907                 if (rc) {
 908                         smc_wr_free_lgr_mem(lgr);
 909                         goto free_wq;
 910                 }
 911                 lgr->net = smc_ib_net(lnk->smcibdev);
 912                 lgr_list = &smc_lgr_list.list;
 913                 lgr_lock = &smc_lgr_list.lock;
 914                 lgr->buf_type = lgr->net->smc.sysctl_smcr_buf_type;
 915                 atomic_inc(&lgr_cnt);
 916         }
 917         smc->conn.lgr = lgr;
 918         spin_lock_bh(lgr_lock);
 919         list_add_tail(&lgr->list, lgr_list);
 920         spin_unlock_bh(lgr_lock);
 921         return 0;
 922
 923 free_wq:
 924         destroy_workqueue(lgr->tx_wq);
 925 free_lgr:
 926         kfree(lgr);
 927 ism_put_vlan:
 928         if (ini->is_smcd && ini->vlan_id)
 929                 smc_ism_put_vlan(ini->ism_dev[ini->ism_selected], ini->vlan_id);
 930 out:
 931         if (rc < 0) {
 932                 if (rc == -ENOMEM)
 933                         rc = SMC_CLC_DECL_MEM;
 934                 else
 935                         rc = SMC_CLC_DECL_INTERR;
 936         }
 937         return rc;
 938 }
 939
 940 static int smc_write_space(struct smc_connection *conn)
 941 {
 942         int buffer_len = conn->peer_rmbe_size;
 943         union smc_host_cursor prod;
 944         union smc_host_cursor cons;
 945         int space;
 946
 947         smc_curs_copy(&prod, &conn->local_tx_ctrl.prod, conn);
 948         smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
 949         /* determine rx_buf space */
 950         space = buffer_len - smc_curs_diff(buffer_len, &cons, &prod);
 951         return space;
 952 }
 953
 954 static int smc_switch_cursor(struct smc_sock *smc, struct smc_cdc_tx_pend *pend,
 955                              struct smc_wr_buf *wr_buf)
 956 {
 957         struct smc_connection *conn = &smc->conn;
 958         union smc_host_cursor cons, fin;
 959         int rc = 0;
 960         int diff;
 961
 962         smc_curs_copy(&conn->tx_curs_sent, &conn->tx_curs_fin, conn);
 963         smc_curs_copy(&fin, &conn->local_tx_ctrl_fin, conn);
 964         /* set prod cursor to old state, enforce tx_rdma_writes() */
 965         smc_curs_copy(&conn->local_tx_ctrl.prod, &fin, conn);
 966         smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
 967
 968         if (smc_curs_comp(conn->peer_rmbe_size, &cons, &fin) < 0) {
 969                 /* cons cursor advanced more than fin, and prod was set
 970                  * fin above, so now prod is smaller than cons. Fix that.
 971                  */
 972                 diff = smc_curs_diff(conn->peer_rmbe_size, &fin, &cons);
 973                 smc_curs_add(conn->sndbuf_desc->len,
 974                              &conn->tx_curs_sent, diff);
 975                 smc_curs_add(conn->sndbuf_desc->len,
 976                              &conn->tx_curs_fin, diff);
 977
 978                 smp_mb__before_atomic();
 979                 atomic_add(diff, &conn->sndbuf_space);
 980                 smp_mb__after_atomic();
 981
 982                 smc_curs_add(conn->peer_rmbe_size,
 983                              &conn->local_tx_ctrl.prod, diff);
 984                 smc_curs_add(conn->peer_rmbe_size,
 985                              &conn->local_tx_ctrl_fin, diff);
 986         }
 987         /* recalculate, value is used by tx_rdma_writes() */
 988         atomic_set(&smc->conn.peer_rmbe_space, smc_write_space(conn));
 989
 990         if (smc->sk.sk_state != SMC_INIT &&
 991             smc->sk.sk_state != SMC_CLOSED) {
 992                 rc = smcr_cdc_msg_send_validation(conn, pend, wr_buf);
 993                 if (!rc) {
 994                         queue_delayed_work(conn->lgr->tx_wq, &conn->tx_work, 0);
 995                         smc->sk.sk_data_ready(&smc->sk);
 996                 }
 997         } else {
 998                 smc_wr_tx_put_slot(conn->lnk,
 999                                    (struct smc_wr_tx_pend_priv *)pend);
1000         }
1001         return rc;
1002 }
1003
1004 void smc_switch_link_and_count(struct smc_connection *conn,
1005                                struct smc_link *to_lnk)
1006 {
1007         atomic_dec(&conn->lnk->conn_cnt);
1008         /* link_hold in smc_conn_create() */
1009         smcr_link_put(conn->lnk);
1010         conn->lnk = to_lnk;
1011         atomic_inc(&conn->lnk->conn_cnt);
1012         /* link_put in smc_conn_free() */
1013         smcr_link_hold(conn->lnk);
1014 }
1015
1016 struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
1017                                   struct smc_link *from_lnk, bool is_dev_err)
1018 {
1019         struct smc_link *to_lnk = NULL;
1020         struct smc_cdc_tx_pend *pend;
1021         struct smc_connection *conn;
1022         struct smc_wr_buf *wr_buf;
1023         struct smc_sock *smc;
1024         struct rb_node *node;
1025         int i, rc = 0;
1026
1027         /* link is inactive, wake up tx waiters */
1028         smc_wr_wakeup_tx_wait(from_lnk);
1029
1030         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1031                 if (!smc_link_active(&lgr->lnk[i]) || i == from_lnk->link_idx)
1032                         continue;
1033                 if (is_dev_err && from_lnk->smcibdev == lgr->lnk[i].smcibdev &&
1034                     from_lnk->ibport == lgr->lnk[i].ibport) {
1035                         continue;
1036                 }
1037                 to_lnk = &lgr->lnk[i];
1038                 break;
1039         }
1040         if (!to_lnk || !smc_wr_tx_link_hold(to_lnk)) {
1041                 smc_lgr_terminate_sched(lgr);
1042                 return NULL;
1043         }
1044 again:
1045         read_lock_bh(&lgr->conns_lock);
1046         for (node = rb_first(&lgr->conns_all); node; node = rb_next(node)) {
1047                 conn = rb_entry(node, struct smc_connection, alert_node);
1048                 if (conn->lnk != from_lnk)
1049                         continue;
1050                 smc = container_of(conn, struct smc_sock, conn);
1051                 /* conn->lnk not yet set in SMC_INIT state */
1052                 if (smc->sk.sk_state == SMC_INIT)
1053                         continue;
1054                 if (smc->sk.sk_state == SMC_CLOSED ||
1055                     smc->sk.sk_state == SMC_PEERCLOSEWAIT1 ||
1056                     smc->sk.sk_state == SMC_PEERCLOSEWAIT2 ||
1057                     smc->sk.sk_state == SMC_APPFINCLOSEWAIT ||
1058                     smc->sk.sk_state == SMC_APPCLOSEWAIT1 ||
1059                     smc->sk.sk_state == SMC_APPCLOSEWAIT2 ||
1060                     smc->sk.sk_state == SMC_PEERFINCLOSEWAIT ||
1061                     smc->sk.sk_state == SMC_PEERABORTWAIT ||
1062                     smc->sk.sk_state == SMC_PROCESSABORT) {
1063                         spin_lock_bh(&conn->send_lock);
1064                         smc_switch_link_and_count(conn, to_lnk);
1065                         spin_unlock_bh(&conn->send_lock);
1066                         continue;
1067                 }
1068                 sock_hold(&smc->sk);
1069                 read_unlock_bh(&lgr->conns_lock);
1070                 /* pre-fetch buffer outside of send_lock, might sleep */
1071                 rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend);
1072                 if (rc)
1073                         goto err_out;
1074                 /* avoid race with smcr_tx_sndbuf_nonempty() */
1075                 spin_lock_bh(&conn->send_lock);
1076                 smc_switch_link_and_count(conn, to_lnk);
1077                 rc = smc_switch_cursor(smc, pend, wr_buf);
1078                 spin_unlock_bh(&conn->send_lock);
1079                 sock_put(&smc->sk);
1080                 if (rc)
1081                         goto err_out;
1082                 goto again;
1083         }
1084         read_unlock_bh(&lgr->conns_lock);
1085         smc_wr_tx_link_put(to_lnk);
1086         return to_lnk;
1087
1088 err_out:
1089         smcr_link_down_cond_sched(to_lnk);
1090         smc_wr_tx_link_put(to_lnk);
1091         return NULL;
1092 }
1093
1094 static void smcr_buf_unuse(struct smc_buf_desc *buf_desc, bool is_rmb,
1095                            struct smc_link_group *lgr)
1096 {
1097         struct mutex *lock;     /* lock buffer list */
1098         int rc;
1099
1100         if (is_rmb && buf_desc->is_conf_rkey && !list_empty(&lgr->list)) {
1101                 /* unregister rmb with peer */
1102                 rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
1103                 if (!rc) {
1104                         /* protect against smc_llc_cli_rkey_exchange() */
1105                         mutex_lock(&lgr->llc_conf_mutex);
1106                         smc_llc_do_delete_rkey(lgr, buf_desc);
1107                         buf_desc->is_conf_rkey = false;
1108                         mutex_unlock(&lgr->llc_conf_mutex);
1109                         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
1110                 }
1111         }
1112
1113         if (buf_desc->is_reg_err) {
1114                 /* buf registration failed, reuse not possible */
1115                 lock = is_rmb ? &lgr->rmbs_lock :
1116                                 &lgr->sndbufs_lock;
1117                 mutex_lock(lock);
1118                 list_del(&buf_desc->list);
1119                 mutex_unlock(lock);
1120
1121                 smc_buf_free(lgr, is_rmb, buf_desc);
1122         } else {
1123                 /* memzero_explicit provides potential memory barrier semantics */
1124                 memzero_explicit(buf_desc->cpu_addr, buf_desc->len);
1125                 WRITE_ONCE(buf_desc->used, 0);
1126         }
1127 }
1128
1129 static void smc_buf_unuse(struct smc_connection *conn,
1130                           struct smc_link_group *lgr)
1131 {
1132         if (conn->sndbuf_desc) {
1133                 if (!lgr->is_smcd && conn->sndbuf_desc->is_vm) {
1134                         smcr_buf_unuse(conn->sndbuf_desc, false, lgr);
1135                 } else {
1136                         memzero_explicit(conn->sndbuf_desc->cpu_addr, conn->sndbuf_desc->len);
1137                         WRITE_ONCE(conn->sndbuf_desc->used, 0);
1138                 }
1139         }
1140         if (conn->rmb_desc) {
1141                 if (!lgr->is_smcd) {
1142                         smcr_buf_unuse(conn->rmb_desc, true, lgr);
1143                 } else {
1144                         memzero_explicit(conn->rmb_desc->cpu_addr,
1145                                          conn->rmb_desc->len + sizeof(struct smcd_cdc_msg));
1146                         WRITE_ONCE(conn->rmb_desc->used, 0);
1147                 }
1148         }
1149 }
1150
1151 /* remove a finished connection from its link group */
1152 void smc_conn_free(struct smc_connection *conn)
1153 {
1154         struct smc_link_group *lgr = conn->lgr;
1155
1156         if (!lgr || conn->freed)
1157                 /* Connection has never been registered in a
1158                  * link group, or has already been freed.
1159                  */
1160                 return;
1161
1162         conn->freed = 1;
1163         if (!smc_conn_lgr_valid(conn))
1164                 /* Connection has already unregistered from
1165                  * link group.
1166                  */
1167                 goto lgr_put;
1168
1169         if (lgr->is_smcd) {
1170                 if (!list_empty(&lgr->list))
1171                         smc_ism_unset_conn(conn);
1172                 tasklet_kill(&conn->rx_tsklet);
1173         } else {
1174                 smc_cdc_wait_pend_tx_wr(conn);
1175                 if (current_work() != &conn->abort_work)
1176                         cancel_work_sync(&conn->abort_work);
1177         }
1178         if (!list_empty(&lgr->list)) {
1179                 smc_buf_unuse(conn, lgr); /* allow buffer reuse */
1180                 smc_lgr_unregister_conn(conn);
1181         }
1182
1183         if (!lgr->conns_num)
1184                 smc_lgr_schedule_free_work(lgr);
1185 lgr_put:
1186         if (!lgr->is_smcd)
1187                 smcr_link_put(conn->lnk); /* link_hold in smc_conn_create() */
1188         smc_lgr_put(lgr); /* lgr_hold in smc_conn_create() */
1189 }
1190
1191 /* unregister a link from a buf_desc */
1192 static void smcr_buf_unmap_link(struct smc_buf_desc *buf_desc, bool is_rmb,
1193                                 struct smc_link *lnk)
1194 {
1195         if (is_rmb || buf_desc->is_vm)
1196                 buf_desc->is_reg_mr[lnk->link_idx] = false;
1197         if (!buf_desc->is_map_ib[lnk->link_idx])
1198                 return;
1199
1200         if ((is_rmb || buf_desc->is_vm) &&
1201             buf_desc->mr[lnk->link_idx]) {
1202                 smc_ib_put_memory_region(buf_desc->mr[lnk->link_idx]);
1203                 buf_desc->mr[lnk->link_idx] = NULL;
1204         }
1205         if (is_rmb)
1206                 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_FROM_DEVICE);
1207         else
1208                 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_TO_DEVICE);
1209
1210         sg_free_table(&buf_desc->sgt[lnk->link_idx]);
1211         buf_desc->is_map_ib[lnk->link_idx] = false;
1212 }
1213
1214 /* unmap all buffers of lgr for a deleted link */
1215 static void smcr_buf_unmap_lgr(struct smc_link *lnk)
1216 {
1217         struct smc_link_group *lgr = lnk->lgr;
1218         struct smc_buf_desc *buf_desc, *bf;
1219         int i;
1220
1221         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1222                 mutex_lock(&lgr->rmbs_lock);
1223                 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list)
1224                         smcr_buf_unmap_link(buf_desc, true, lnk);
1225                 mutex_unlock(&lgr->rmbs_lock);
1226                 mutex_lock(&lgr->sndbufs_lock);
1227                 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i],
1228                                          list)
1229                         smcr_buf_unmap_link(buf_desc, false, lnk);
1230                 mutex_unlock(&lgr->sndbufs_lock);
1231         }
1232 }
1233
1234 static void smcr_rtoken_clear_link(struct smc_link *lnk)
1235 {
1236         struct smc_link_group *lgr = lnk->lgr;
1237         int i;
1238
1239         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1240                 lgr->rtokens[i][lnk->link_idx].rkey = 0;
1241                 lgr->rtokens[i][lnk->link_idx].dma_addr = 0;
1242         }
1243 }
1244
1245 static void __smcr_link_clear(struct smc_link *lnk)
1246 {
1247         struct smc_link_group *lgr = lnk->lgr;
1248         struct smc_ib_device *smcibdev;
1249
1250         smc_wr_free_link_mem(lnk);
1251         smc_ibdev_cnt_dec(lnk);
1252         put_device(&lnk->smcibdev->ibdev->dev);
1253         smcibdev = lnk->smcibdev;
1254         memset(lnk, 0, sizeof(struct smc_link));
1255         lnk->state = SMC_LNK_UNUSED;
1256         if (!atomic_dec_return(&smcibdev->lnk_cnt))
1257                 wake_up(&smcibdev->lnks_deleted);
1258         smc_lgr_put(lgr); /* lgr_hold in smcr_link_init() */
1259 }
1260
1261 /* must be called under lgr->llc_conf_mutex lock */
1262 void smcr_link_clear(struct smc_link *lnk, bool log)
1263 {
1264         if (!lnk->lgr || lnk->clearing ||
1265             lnk->state == SMC_LNK_UNUSED)
1266                 return;
1267         lnk->clearing = 1;
1268         lnk->peer_qpn = 0;
1269         smc_llc_link_clear(lnk, log);
1270         smcr_buf_unmap_lgr(lnk);
1271         smcr_rtoken_clear_link(lnk);
1272         smc_ib_modify_qp_error(lnk);
1273         smc_wr_free_link(lnk);
1274         smc_ib_destroy_queue_pair(lnk);
1275         smc_ib_dealloc_protection_domain(lnk);
1276         smcr_link_put(lnk); /* theoretically last link_put */
1277 }
1278
1279 void smcr_link_hold(struct smc_link *lnk)
1280 {
1281         refcount_inc(&lnk->refcnt);
1282 }
1283
1284 void smcr_link_put(struct smc_link *lnk)
1285 {
1286         if (refcount_dec_and_test(&lnk->refcnt))
1287                 __smcr_link_clear(lnk);
1288 }
1289
1290 static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb,
1291                           struct smc_buf_desc *buf_desc)
1292 {
1293         int i;
1294
1295         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1296                 smcr_buf_unmap_link(buf_desc, is_rmb, &lgr->lnk[i]);
1297
1298         if (!buf_desc->is_vm && buf_desc->pages)
1299                 __free_pages(buf_desc->pages, buf_desc->order);
1300         else if (buf_desc->is_vm && buf_desc->cpu_addr)
1301                 vfree(buf_desc->cpu_addr);
1302         kfree(buf_desc);
1303 }
1304
1305 static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb,
1306                           struct smc_buf_desc *buf_desc)
1307 {
1308         if (is_dmb) {
1309                 /* restore original buf len */
1310                 buf_desc->len += sizeof(struct smcd_cdc_msg);
1311                 smc_ism_unregister_dmb(lgr->smcd, buf_desc);
1312         } else {
1313                 kfree(buf_desc->cpu_addr);
1314         }
1315         kfree(buf_desc);
1316 }
1317
1318 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
1319                          struct smc_buf_desc *buf_desc)
1320 {
1321         if (lgr->is_smcd)
1322                 smcd_buf_free(lgr, is_rmb, buf_desc);
1323         else
1324                 smcr_buf_free(lgr, is_rmb, buf_desc);
1325 }
1326
1327 static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb)
1328 {
1329         struct smc_buf_desc *buf_desc, *bf_desc;
1330         struct list_head *buf_list;
1331         int i;
1332
1333         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1334                 if (is_rmb)
1335                         buf_list = &lgr->rmbs[i];
1336                 else
1337                         buf_list = &lgr->sndbufs[i];
1338                 list_for_each_entry_safe(buf_desc, bf_desc, buf_list,
1339                                          list) {
1340                         list_del(&buf_desc->list);
1341                         smc_buf_free(lgr, is_rmb, buf_desc);
1342                 }
1343         }
1344 }
1345
1346 static void smc_lgr_free_bufs(struct smc_link_group *lgr)
1347 {
1348         /* free send buffers */
1349         __smc_lgr_free_bufs(lgr, false);
1350         /* free rmbs */
1351         __smc_lgr_free_bufs(lgr, true);
1352 }
1353
1354 /* won't be freed until no one accesses to lgr anymore */
1355 static void __smc_lgr_free(struct smc_link_group *lgr)
1356 {
1357         smc_lgr_free_bufs(lgr);
1358         if (lgr->is_smcd) {
1359                 if (!atomic_dec_return(&lgr->smcd->lgr_cnt))
1360                         wake_up(&lgr->smcd->lgrs_deleted);
1361         } else {
1362                 smc_wr_free_lgr_mem(lgr);
1363                 if (!atomic_dec_return(&lgr_cnt))
1364                         wake_up(&lgrs_deleted);
1365         }
1366         kfree(lgr);
1367 }
1368
1369 /* remove a link group */
1370 static void smc_lgr_free(struct smc_link_group *lgr)
1371 {
1372         int i;
1373
1374         if (!lgr->is_smcd) {
1375                 mutex_lock(&lgr->llc_conf_mutex);
1376                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1377                         if (lgr->lnk[i].state != SMC_LNK_UNUSED)
1378                                 smcr_link_clear(&lgr->lnk[i], false);
1379                 }
1380                 mutex_unlock(&lgr->llc_conf_mutex);
1381                 smc_llc_lgr_clear(lgr);
1382         }
1383
1384         destroy_workqueue(lgr->tx_wq);
1385         if (lgr->is_smcd) {
1386                 smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
1387                 put_device(&lgr->smcd->dev);
1388         }
1389         smc_lgr_put(lgr); /* theoretically last lgr_put */
1390 }
1391
1392 void smc_lgr_hold(struct smc_link_group *lgr)
1393 {
1394         refcount_inc(&lgr->refcnt);
1395 }
1396
1397 void smc_lgr_put(struct smc_link_group *lgr)
1398 {
1399         if (refcount_dec_and_test(&lgr->refcnt))
1400                 __smc_lgr_free(lgr);
1401 }
1402
1403 static void smc_sk_wake_ups(struct smc_sock *smc)
1404 {
1405         smc->sk.sk_write_space(&smc->sk);
1406         smc->sk.sk_data_ready(&smc->sk);
1407         smc->sk.sk_state_change(&smc->sk);
1408 }
1409
1410 /* kill a connection */
1411 static void smc_conn_kill(struct smc_connection *conn, bool soft)
1412 {
1413         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1414
1415         if (conn->lgr->is_smcd && conn->lgr->peer_shutdown)
1416                 conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
1417         else
1418                 smc_close_abort(conn);
1419         conn->killed = 1;
1420         smc->sk.sk_err = ECONNABORTED;
1421         smc_sk_wake_ups(smc);
1422         if (conn->lgr->is_smcd) {
1423                 smc_ism_unset_conn(conn);
1424                 if (soft)
1425                         tasklet_kill(&conn->rx_tsklet);
1426                 else
1427                         tasklet_unlock_wait(&conn->rx_tsklet);
1428         } else {
1429                 smc_cdc_wait_pend_tx_wr(conn);
1430         }
1431         smc_lgr_unregister_conn(conn);
1432         smc_close_active_abort(smc);
1433 }
1434
1435 static void smc_lgr_cleanup(struct smc_link_group *lgr)
1436 {
1437         if (lgr->is_smcd) {
1438                 smc_ism_signal_shutdown(lgr);
1439         } else {
1440                 u32 rsn = lgr->llc_termination_rsn;
1441
1442                 if (!rsn)
1443                         rsn = SMC_LLC_DEL_PROG_INIT_TERM;
1444                 smc_llc_send_link_delete_all(lgr, false, rsn);
1445                 smcr_lgr_link_deactivate_all(lgr);
1446         }
1447 }
1448
1449 /* terminate link group
1450  * @soft: true if link group shutdown can take its time
1451  *        false if immediate link group shutdown is required
1452  */
1453 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft)
1454 {
1455         struct smc_connection *conn;
1456         struct smc_sock *smc;
1457         struct rb_node *node;
1458
1459         if (lgr->terminating)
1460                 return; /* lgr already terminating */
1461         /* cancel free_work sync, will terminate when lgr->freeing is set */
1462         cancel_delayed_work(&lgr->free_work);
1463         lgr->terminating = 1;
1464
1465         /* kill remaining link group connections */
1466         read_lock_bh(&lgr->conns_lock);
1467         node = rb_first(&lgr->conns_all);
1468         while (node) {
1469                 read_unlock_bh(&lgr->conns_lock);
1470                 conn = rb_entry(node, struct smc_connection, alert_node);
1471                 smc = container_of(conn, struct smc_sock, conn);
1472                 sock_hold(&smc->sk); /* sock_put below */
1473                 lock_sock(&smc->sk);
1474                 smc_conn_kill(conn, soft);
1475                 release_sock(&smc->sk);
1476                 sock_put(&smc->sk); /* sock_hold above */
1477                 read_lock_bh(&lgr->conns_lock);
1478                 node = rb_first(&lgr->conns_all);
1479         }
1480         read_unlock_bh(&lgr->conns_lock);
1481         smc_lgr_cleanup(lgr);
1482         smc_lgr_free(lgr);
1483 }
1484
1485 /* unlink link group and schedule termination */
1486 void smc_lgr_terminate_sched(struct smc_link_group *lgr)
1487 {
1488         spinlock_t *lgr_lock;
1489
1490         smc_lgr_list_head(lgr, &lgr_lock);
1491         spin_lock_bh(lgr_lock);
1492         if (list_empty(&lgr->list) || lgr->terminating || lgr->freeing) {
1493                 spin_unlock_bh(lgr_lock);
1494                 return; /* lgr already terminating */
1495         }
1496         list_del_init(&lgr->list);
1497         lgr->freeing = 1;
1498         spin_unlock_bh(lgr_lock);
1499         schedule_work(&lgr->terminate_work);
1500 }
1501
1502 /* Called when peer lgr shutdown (regularly or abnormally) is received */
1503 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
1504 {
1505         struct smc_link_group *lgr, *l;
1506         LIST_HEAD(lgr_free_list);
1507
1508         /* run common cleanup function and build free list */
1509         spin_lock_bh(&dev->lgr_lock);
1510         list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) {
1511                 if ((!peer_gid || lgr->peer_gid == peer_gid) &&
1512                     (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
1513                         if (peer_gid) /* peer triggered termination */
1514                                 lgr->peer_shutdown = 1;
1515                         list_move(&lgr->list, &lgr_free_list);
1516                         lgr->freeing = 1;
1517                 }
1518         }
1519         spin_unlock_bh(&dev->lgr_lock);
1520
1521         /* cancel the regular free workers and actually free lgrs */
1522         list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
1523                 list_del_init(&lgr->list);
1524                 schedule_work(&lgr->terminate_work);
1525         }
1526 }
1527
1528 /* Called when an SMCD device is removed or the smc module is unloaded */
1529 void smc_smcd_terminate_all(struct smcd_dev *smcd)
1530 {
1531         struct smc_link_group *lgr, *lg;
1532         LIST_HEAD(lgr_free_list);
1533
1534         spin_lock_bh(&smcd->lgr_lock);
1535         list_splice_init(&smcd->lgr_list, &lgr_free_list);
1536         list_for_each_entry(lgr, &lgr_free_list, list)
1537                 lgr->freeing = 1;
1538         spin_unlock_bh(&smcd->lgr_lock);
1539
1540         list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1541                 list_del_init(&lgr->list);
1542                 __smc_lgr_terminate(lgr, false);
1543         }
1544
1545         if (atomic_read(&smcd->lgr_cnt))
1546                 wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt));
1547 }
1548
1549 /* Called when an SMCR device is removed or the smc module is unloaded.
1550  * If smcibdev is given, all SMCR link groups using this device are terminated.
1551  * If smcibdev is NULL, all SMCR link groups are terminated.
1552  */
1553 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
1554 {
1555         struct smc_link_group *lgr, *lg;
1556         LIST_HEAD(lgr_free_list);
1557         int i;
1558
1559         spin_lock_bh(&smc_lgr_list.lock);
1560         if (!smcibdev) {
1561                 list_splice_init(&smc_lgr_list.list, &lgr_free_list);
1562                 list_for_each_entry(lgr, &lgr_free_list, list)
1563                         lgr->freeing = 1;
1564         } else {
1565                 list_for_each_entry_safe(lgr, lg, &smc_lgr_list.list, list) {
1566                         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1567                                 if (lgr->lnk[i].smcibdev == smcibdev)
1568                                         smcr_link_down_cond_sched(&lgr->lnk[i]);
1569                         }
1570                 }
1571         }
1572         spin_unlock_bh(&smc_lgr_list.lock);
1573
1574         list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1575                 list_del_init(&lgr->list);
1576                 smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_OP_INIT_TERM);
1577                 __smc_lgr_terminate(lgr, false);
1578         }
1579
1580         if (smcibdev) {
1581                 if (atomic_read(&smcibdev->lnk_cnt))
1582                         wait_event(smcibdev->lnks_deleted,
1583                                    !atomic_read(&smcibdev->lnk_cnt));
1584         } else {
1585                 if (atomic_read(&lgr_cnt))
1586                         wait_event(lgrs_deleted, !atomic_read(&lgr_cnt));
1587         }
1588 }
1589
1590 /* set new lgr type and clear all asymmetric link tagging */
1591 void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type)
1592 {
1593         char *lgr_type = "";
1594         int i;
1595
1596         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1597                 if (smc_link_usable(&lgr->lnk[i]))
1598                         lgr->lnk[i].link_is_asym = false;
1599         if (lgr->type == new_type)
1600                 return;
1601         lgr->type = new_type;
1602
1603         switch (lgr->type) {
1604         case SMC_LGR_NONE:
1605                 lgr_type = "NONE";
1606                 break;
1607         case SMC_LGR_SINGLE:
1608                 lgr_type = "SINGLE";
1609                 break;
1610         case SMC_LGR_SYMMETRIC:
1611                 lgr_type = "SYMMETRIC";
1612                 break;
1613         case SMC_LGR_ASYMMETRIC_PEER:
1614                 lgr_type = "ASYMMETRIC_PEER";
1615                 break;
1616         case SMC_LGR_ASYMMETRIC_LOCAL:
1617                 lgr_type = "ASYMMETRIC_LOCAL";
1618                 break;
1619         }
1620         pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu state changed: "
1621                             "%s, pnetid %.16s\n", SMC_LGR_ID_SIZE, &lgr->id,
1622                             lgr->net->net_cookie, lgr_type, lgr->pnet_id);
1623 }
1624
1625 /* set new lgr type and tag a link as asymmetric */
1626 void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
1627                             enum smc_lgr_type new_type, int asym_lnk_idx)
1628 {
1629         smcr_lgr_set_type(lgr, new_type);
1630         lgr->lnk[asym_lnk_idx].link_is_asym = true;
1631 }
1632
1633 /* abort connection, abort_work scheduled from tasklet context */
1634 static void smc_conn_abort_work(struct work_struct *work)
1635 {
1636         struct smc_connection *conn = container_of(work,
1637                                                    struct smc_connection,
1638                                                    abort_work);
1639         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1640
1641         lock_sock(&smc->sk);
1642         smc_conn_kill(conn, true);
1643         release_sock(&smc->sk);
1644         sock_put(&smc->sk); /* sock_hold done by schedulers of abort_work */
1645 }
1646
1647 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport)
1648 {
1649         struct smc_link_group *lgr, *n;
1650
1651         list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1652                 struct smc_link *link;
1653
1654                 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1655                             SMC_MAX_PNETID_LEN) ||
1656                     lgr->type == SMC_LGR_SYMMETRIC ||
1657                     lgr->type == SMC_LGR_ASYMMETRIC_PEER ||
1658                     !rdma_dev_access_netns(smcibdev->ibdev, lgr->net))
1659                         continue;
1660
1661                 /* trigger local add link processing */
1662                 link = smc_llc_usable_link(lgr);
1663                 if (link)
1664                         smc_llc_add_link_local(link);
1665         }
1666 }
1667
1668 /* link is down - switch connections to alternate link,
1669  * must be called under lgr->llc_conf_mutex lock
1670  */
1671 static void smcr_link_down(struct smc_link *lnk)
1672 {
1673         struct smc_link_group *lgr = lnk->lgr;
1674         struct smc_link *to_lnk;
1675         int del_link_id;
1676
1677         if (!lgr || lnk->state == SMC_LNK_UNUSED || list_empty(&lgr->list))
1678                 return;
1679
1680         to_lnk = smc_switch_conns(lgr, lnk, true);
1681         if (!to_lnk) { /* no backup link available */
1682                 smcr_link_clear(lnk, true);
1683                 return;
1684         }
1685         smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
1686         del_link_id = lnk->link_id;
1687
1688         if (lgr->role == SMC_SERV) {
1689                 /* trigger local delete link processing */
1690                 smc_llc_srv_delete_link_local(to_lnk, del_link_id);
1691         } else {
1692                 if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
1693                         /* another llc task is ongoing */
1694                         mutex_unlock(&lgr->llc_conf_mutex);
1695                         wait_event_timeout(lgr->llc_flow_waiter,
1696                                 (list_empty(&lgr->list) ||
1697                                  lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE),
1698                                 SMC_LLC_WAIT_TIME);
1699                         mutex_lock(&lgr->llc_conf_mutex);
1700                 }
1701                 if (!list_empty(&lgr->list)) {
1702                         smc_llc_send_delete_link(to_lnk, del_link_id,
1703                                                  SMC_LLC_REQ, true,
1704                                                  SMC_LLC_DEL_LOST_PATH);
1705                         smcr_link_clear(lnk, true);
1706                 }
1707                 wake_up(&lgr->llc_flow_waiter); /* wake up next waiter */
1708         }
1709 }
1710
1711 /* must be called under lgr->llc_conf_mutex lock */
1712 void smcr_link_down_cond(struct smc_link *lnk)
1713 {
1714         if (smc_link_downing(&lnk->state)) {
1715                 trace_smcr_link_down(lnk, __builtin_return_address(0));
1716                 smcr_link_down(lnk);
1717         }
1718 }
1719
1720 /* will get the lgr->llc_conf_mutex lock */
1721 void smcr_link_down_cond_sched(struct smc_link *lnk)
1722 {
1723         if (smc_link_downing(&lnk->state)) {
1724                 trace_smcr_link_down(lnk, __builtin_return_address(0));
1725                 schedule_work(&lnk->link_down_wrk);
1726         }
1727 }
1728
1729 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport)
1730 {
1731         struct smc_link_group *lgr, *n;
1732         int i;
1733
1734         list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1735                 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1736                             SMC_MAX_PNETID_LEN))
1737                         continue; /* lgr is not affected */
1738                 if (list_empty(&lgr->list))
1739                         continue;
1740                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1741                         struct smc_link *lnk = &lgr->lnk[i];
1742
1743                         if (smc_link_usable(lnk) &&
1744                             lnk->smcibdev == smcibdev && lnk->ibport == ibport)
1745                                 smcr_link_down_cond_sched(lnk);
1746                 }
1747         }
1748 }
1749
1750 static void smc_link_down_work(struct work_struct *work)
1751 {
1752         struct smc_link *link = container_of(work, struct smc_link,
1753                                              link_down_wrk);
1754         struct smc_link_group *lgr = link->lgr;
1755
1756         if (list_empty(&lgr->list))
1757                 return;
1758         wake_up_all(&lgr->llc_msg_waiter);
1759         mutex_lock(&lgr->llc_conf_mutex);
1760         smcr_link_down(link);
1761         mutex_unlock(&lgr->llc_conf_mutex);
1762 }
1763
1764 static int smc_vlan_by_tcpsk_walk(struct net_device *lower_dev,
1765                                   struct netdev_nested_priv *priv)
1766 {
1767         unsigned short *vlan_id = (unsigned short *)priv->data;
1768
1769         if (is_vlan_dev(lower_dev)) {
1770                 *vlan_id = vlan_dev_vlan_id(lower_dev);
1771                 return 1;
1772         }
1773
1774         return 0;
1775 }
1776
1777 /* Determine vlan of internal TCP socket. */
1778 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
1779 {
1780         struct dst_entry *dst = sk_dst_get(clcsock->sk);
1781         struct netdev_nested_priv priv;
1782         struct net_device *ndev;
1783         int rc = 0;
1784
1785         ini->vlan_id = 0;
1786         if (!dst) {
1787                 rc = -ENOTCONN;
1788                 goto out;
1789         }
1790         if (!dst->dev) {
1791                 rc = -ENODEV;
1792                 goto out_rel;
1793         }
1794
1795         ndev = dst->dev;
1796         if (is_vlan_dev(ndev)) {
1797                 ini->vlan_id = vlan_dev_vlan_id(ndev);
1798                 goto out_rel;
1799         }
1800
1801         priv.data = (void *)&ini->vlan_id;
1802         rtnl_lock();
1803         netdev_walk_all_lower_dev(ndev, smc_vlan_by_tcpsk_walk, &priv);
1804         rtnl_unlock();
1805
1806 out_rel:
1807         dst_release(dst);
1808 out:
1809         return rc;
1810 }
1811
1812 static bool smcr_lgr_match(struct smc_link_group *lgr, u8 smcr_version,
1813                            u8 peer_systemid[],
1814                            u8 peer_gid[],
1815                            u8 peer_mac_v1[],
1816                            enum smc_lgr_role role, u32 clcqpn,
1817                            struct net *net)
1818 {
1819         struct smc_link *lnk;
1820         int i;
1821
1822         if (memcmp(lgr->peer_systemid, peer_systemid, SMC_SYSTEMID_LEN) ||
1823             lgr->role != role)
1824                 return false;
1825
1826         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1827                 lnk = &lgr->lnk[i];
1828
1829                 if (!smc_link_active(lnk))
1830                         continue;
1831                 /* use verbs API to check netns, instead of lgr->net */
1832                 if (!rdma_dev_access_netns(lnk->smcibdev->ibdev, net))
1833                         return false;
1834                 if ((lgr->role == SMC_SERV || lnk->peer_qpn == clcqpn) &&
1835                     !memcmp(lnk->peer_gid, peer_gid, SMC_GID_SIZE) &&
1836                     (smcr_version == SMC_V2 ||
1837                      !memcmp(lnk->peer_mac, peer_mac_v1, ETH_ALEN)))
1838                         return true;
1839         }
1840         return false;
1841 }
1842
1843 static bool smcd_lgr_match(struct smc_link_group *lgr,
1844                            struct smcd_dev *smcismdev, u64 peer_gid)
1845 {
1846         return lgr->peer_gid == peer_gid && lgr->smcd == smcismdev;
1847 }
1848
1849 /* create a new SMC connection (and a new link group if necessary) */
1850 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
1851 {
1852         struct smc_connection *conn = &smc->conn;
1853         struct net *net = sock_net(&smc->sk);
1854         struct list_head *lgr_list;
1855         struct smc_link_group *lgr;
1856         enum smc_lgr_role role;
1857         spinlock_t *lgr_lock;
1858         int rc = 0;
1859
1860         lgr_list = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_list :
1861                                   &smc_lgr_list.list;
1862         lgr_lock = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_lock :
1863                                   &smc_lgr_list.lock;
1864         ini->first_contact_local = 1;
1865         role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
1866         if (role == SMC_CLNT && ini->first_contact_peer)
1867                 /* create new link group as well */
1868                 goto create;
1869
1870         /* determine if an existing link group can be reused */
1871         spin_lock_bh(lgr_lock);
1872         list_for_each_entry(lgr, lgr_list, list) {
1873                 write_lock_bh(&lgr->conns_lock);
1874                 if ((ini->is_smcd ?
1875                      smcd_lgr_match(lgr, ini->ism_dev[ini->ism_selected],
1876                                     ini->ism_peer_gid[ini->ism_selected]) :
1877                      smcr_lgr_match(lgr, ini->smcr_version,
1878                                     ini->peer_systemid,
1879                                     ini->peer_gid, ini->peer_mac, role,
1880                                     ini->ib_clcqpn, net)) &&
1881                     !lgr->sync_err &&
1882                     (ini->smcd_version == SMC_V2 ||
1883                      lgr->vlan_id == ini->vlan_id) &&
1884                     (role == SMC_CLNT || ini->is_smcd ||
1885                     (lgr->conns_num < SMC_RMBS_PER_LGR_MAX &&
1886                       !bitmap_full(lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX)))) {
1887                         /* link group found */
1888                         ini->first_contact_local = 0;
1889                         conn->lgr = lgr;
1890                         rc = smc_lgr_register_conn(conn, false);
1891                         write_unlock_bh(&lgr->conns_lock);
1892                         if (!rc && delayed_work_pending(&lgr->free_work))
1893                                 cancel_delayed_work(&lgr->free_work);
1894                         break;
1895                 }
1896                 write_unlock_bh(&lgr->conns_lock);
1897         }
1898         spin_unlock_bh(lgr_lock);
1899         if (rc)
1900                 return rc;
1901
1902         if (role == SMC_CLNT && !ini->first_contact_peer &&
1903             ini->first_contact_local) {
1904                 /* Server reuses a link group, but Client wants to start
1905                  * a new one
1906                  * send out_of_sync decline, reason synchr. error
1907                  */
1908                 return SMC_CLC_DECL_SYNCERR;
1909         }
1910
1911 create:
1912         if (ini->first_contact_local) {
1913                 rc = smc_lgr_create(smc, ini);
1914                 if (rc)
1915                         goto out;
1916                 lgr = conn->lgr;
1917                 write_lock_bh(&lgr->conns_lock);
1918                 rc = smc_lgr_register_conn(conn, true);
1919                 write_unlock_bh(&lgr->conns_lock);
1920                 if (rc) {
1921                         smc_lgr_cleanup_early(lgr);
1922                         goto out;
1923                 }
1924         }
1925         smc_lgr_hold(conn->lgr); /* lgr_put in smc_conn_free() */
1926         if (!conn->lgr->is_smcd)
1927                 smcr_link_hold(conn->lnk); /* link_put in smc_conn_free() */
1928         conn->freed = 0;
1929         conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
1930         conn->local_tx_ctrl.len = SMC_WR_TX_SIZE;
1931         conn->urg_state = SMC_URG_READ;
1932         init_waitqueue_head(&conn->cdc_pend_tx_wq);
1933         INIT_WORK(&smc->conn.abort_work, smc_conn_abort_work);
1934         if (ini->is_smcd) {
1935                 conn->rx_off = sizeof(struct smcd_cdc_msg);
1936                 smcd_cdc_rx_init(conn); /* init tasklet for this conn */
1937         } else {
1938                 conn->rx_off = 0;
1939         }
1940 #ifndef KERNEL_HAS_ATOMIC64
1941         spin_lock_init(&conn->acurs_lock);
1942 #endif
1943
1944 out:
1945         return rc;
1946 }
1947
1948 #define SMCD_DMBE_SIZES         6 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */
1949 #define SMCR_RMBE_SIZES         5 /* 0 -> 16KB, 1 -> 32KB, .. 5 -> 512KB */
1950
1951 /* convert the RMB size into the compressed notation (minimum 16K, see
1952  * SMCD/R_DMBE_SIZES.
1953  * In contrast to plain ilog2, this rounds towards the next power of 2,
1954  * so the socket application gets at least its desired sndbuf / rcvbuf size.
1955  */
1956 static u8 smc_compress_bufsize(int size, bool is_smcd, bool is_rmb)
1957 {
1958         const unsigned int max_scat = SG_MAX_SINGLE_ALLOC * PAGE_SIZE;
1959         u8 compressed;
1960
1961         if (size <= SMC_BUF_MIN_SIZE)
1962                 return 0;
1963
1964         size = (size - 1) >> 14;  /* convert to 16K multiple */
1965         compressed = min_t(u8, ilog2(size) + 1,
1966                            is_smcd ? SMCD_DMBE_SIZES : SMCR_RMBE_SIZES);
1967
1968         if (!is_smcd && is_rmb)
1969                 /* RMBs are backed by & limited to max size of scatterlists */
1970                 compressed = min_t(u8, compressed, ilog2(max_scat >> 14));
1971
1972         return compressed;
1973 }
1974
1975 /* convert the RMB size from compressed notation into integer */
1976 int smc_uncompress_bufsize(u8 compressed)
1977 {
1978         u32 size;
1979
1980         size = 0x00000001 << (((int)compressed) + 14);
1981         return (int)size;
1982 }
1983
1984 /* try to reuse a sndbuf or rmb description slot for a certain
1985  * buffer size; if not available, return NULL
1986  */
1987 static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize,
1988                                              struct mutex *lock,
1989                                              struct list_head *buf_list)
1990 {
1991         struct smc_buf_desc *buf_slot;
1992
1993         mutex_lock(lock);
1994         list_for_each_entry(buf_slot, buf_list, list) {
1995                 if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
1996                         mutex_unlock(lock);
1997                         return buf_slot;
1998                 }
1999         }
2000         mutex_unlock(lock);
2001         return NULL;
2002 }
2003
2004 /* one of the conditions for announcing a receiver's current window size is
2005  * that it "results in a minimum increase in the window size of 10% of the
2006  * receive buffer space" [RFC7609]
2007  */
2008 static inline int smc_rmb_wnd_update_limit(int rmbe_size)
2009 {
2010         return max_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
2011 }
2012
2013 /* map an buf to a link */
2014 static int smcr_buf_map_link(struct smc_buf_desc *buf_desc, bool is_rmb,
2015                              struct smc_link *lnk)
2016 {
2017         int rc, i, nents, offset, buf_size, size, access_flags;
2018         struct scatterlist *sg;
2019         void *buf;
2020
2021         if (buf_desc->is_map_ib[lnk->link_idx])
2022                 return 0;
2023
2024         if (buf_desc->is_vm) {
2025                 buf = buf_desc->cpu_addr;
2026                 buf_size = buf_desc->len;
2027                 offset = offset_in_page(buf_desc->cpu_addr);
2028                 nents = PAGE_ALIGN(buf_size + offset) / PAGE_SIZE;
2029         } else {
2030                 nents = 1;
2031         }
2032
2033         rc = sg_alloc_table(&buf_desc->sgt[lnk->link_idx], nents, GFP_KERNEL);
2034         if (rc)
2035                 return rc;
2036
2037         if (buf_desc->is_vm) {
2038                 /* virtually contiguous buffer */
2039                 for_each_sg(buf_desc->sgt[lnk->link_idx].sgl, sg, nents, i) {
2040                         size = min_t(int, PAGE_SIZE - offset, buf_size);
2041                         sg_set_page(sg, vmalloc_to_page(buf), size, offset);
2042                         buf += size / sizeof(*buf);
2043                         buf_size -= size;
2044                         offset = 0;
2045                 }
2046         } else {
2047                 /* physically contiguous buffer */
2048                 sg_set_buf(buf_desc->sgt[lnk->link_idx].sgl,
2049                            buf_desc->cpu_addr, buf_desc->len);
2050         }
2051
2052         /* map sg table to DMA address */
2053         rc = smc_ib_buf_map_sg(lnk, buf_desc,
2054                                is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2055         /* SMC protocol depends on mapping to one DMA address only */
2056         if (rc != nents) {
2057                 rc = -EAGAIN;
2058                 goto free_table;
2059         }
2060
2061         buf_desc->is_dma_need_sync |=
2062                 smc_ib_is_sg_need_sync(lnk, buf_desc) << lnk->link_idx;
2063
2064         if (is_rmb || buf_desc->is_vm) {
2065                 /* create a new memory region for the RMB or vzalloced sndbuf */
2066                 access_flags = is_rmb ?
2067                                IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
2068                                IB_ACCESS_LOCAL_WRITE;
2069
2070                 rc = smc_ib_get_memory_region(lnk->roce_pd, access_flags,
2071                                               buf_desc, lnk->link_idx);
2072                 if (rc)
2073                         goto buf_unmap;
2074                 smc_ib_sync_sg_for_device(lnk, buf_desc,
2075                                           is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2076         }
2077         buf_desc->is_map_ib[lnk->link_idx] = true;
2078         return 0;
2079
2080 buf_unmap:
2081         smc_ib_buf_unmap_sg(lnk, buf_desc,
2082                             is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2083 free_table:
2084         sg_free_table(&buf_desc->sgt[lnk->link_idx]);
2085         return rc;
2086 }
2087
2088 /* register a new buf on IB device, rmb or vzalloced sndbuf
2089  * must be called under lgr->llc_conf_mutex lock
2090  */
2091 int smcr_link_reg_buf(struct smc_link *link, struct smc_buf_desc *buf_desc)
2092 {
2093         if (list_empty(&link->lgr->list))
2094                 return -ENOLINK;
2095         if (!buf_desc->is_reg_mr[link->link_idx]) {
2096                 /* register memory region for new buf */
2097                 if (buf_desc->is_vm)
2098                         buf_desc->mr[link->link_idx]->iova =
2099                                 (uintptr_t)buf_desc->cpu_addr;
2100                 if (smc_wr_reg_send(link, buf_desc->mr[link->link_idx])) {
2101                         buf_desc->is_reg_err = true;
2102                         return -EFAULT;
2103                 }
2104                 buf_desc->is_reg_mr[link->link_idx] = true;
2105         }
2106         return 0;
2107 }
2108
2109 static int _smcr_buf_map_lgr(struct smc_link *lnk, struct mutex *lock,
2110                              struct list_head *lst, bool is_rmb)
2111 {
2112         struct smc_buf_desc *buf_desc, *bf;
2113         int rc = 0;
2114
2115         mutex_lock(lock);
2116         list_for_each_entry_safe(buf_desc, bf, lst, list) {
2117                 if (!buf_desc->used)
2118                         continue;
2119                 rc = smcr_buf_map_link(buf_desc, is_rmb, lnk);
2120                 if (rc)
2121                         goto out;
2122         }
2123 out:
2124         mutex_unlock(lock);
2125         return rc;
2126 }
2127
2128 /* map all used buffers of lgr for a new link */
2129 int smcr_buf_map_lgr(struct smc_link *lnk)
2130 {
2131         struct smc_link_group *lgr = lnk->lgr;
2132         int i, rc = 0;
2133
2134         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2135                 rc = _smcr_buf_map_lgr(lnk, &lgr->rmbs_lock,
2136                                        &lgr->rmbs[i], true);
2137                 if (rc)
2138                         return rc;
2139                 rc = _smcr_buf_map_lgr(lnk, &lgr->sndbufs_lock,
2140                                        &lgr->sndbufs[i], false);
2141                 if (rc)
2142                         return rc;
2143         }
2144         return 0;
2145 }
2146
2147 /* register all used buffers of lgr for a new link,
2148  * must be called under lgr->llc_conf_mutex lock
2149  */
2150 int smcr_buf_reg_lgr(struct smc_link *lnk)
2151 {
2152         struct smc_link_group *lgr = lnk->lgr;
2153         struct smc_buf_desc *buf_desc, *bf;
2154         int i, rc = 0;
2155
2156         /* reg all RMBs for a new link */
2157         mutex_lock(&lgr->rmbs_lock);
2158         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2159                 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list) {
2160                         if (!buf_desc->used)
2161                                 continue;
2162                         rc = smcr_link_reg_buf(lnk, buf_desc);
2163                         if (rc) {
2164                                 mutex_unlock(&lgr->rmbs_lock);
2165                                 return rc;
2166                         }
2167                 }
2168         }
2169         mutex_unlock(&lgr->rmbs_lock);
2170
2171         if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
2172                 return rc;
2173
2174         /* reg all vzalloced sndbufs for a new link */
2175         mutex_lock(&lgr->sndbufs_lock);
2176         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2177                 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i], list) {
2178                         if (!buf_desc->used || !buf_desc->is_vm)
2179                                 continue;
2180                         rc = smcr_link_reg_buf(lnk, buf_desc);
2181                         if (rc) {
2182                                 mutex_unlock(&lgr->sndbufs_lock);
2183                                 return rc;
2184                         }
2185                 }
2186         }
2187         mutex_unlock(&lgr->sndbufs_lock);
2188         return rc;
2189 }
2190
2191 static struct smc_buf_desc *smcr_new_buf_create(struct smc_link_group *lgr,
2192                                                 bool is_rmb, int bufsize)
2193 {
2194         struct smc_buf_desc *buf_desc;
2195
2196         /* try to alloc a new buffer */
2197         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
2198         if (!buf_desc)
2199                 return ERR_PTR(-ENOMEM);
2200
2201         switch (lgr->buf_type) {
2202         case SMCR_PHYS_CONT_BUFS:
2203         case SMCR_MIXED_BUFS:
2204                 buf_desc->order = get_order(bufsize);
2205                 buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN |
2206                                               __GFP_NOMEMALLOC | __GFP_COMP |
2207                                               __GFP_NORETRY | __GFP_ZERO,
2208                                               buf_desc->order);
2209                 if (buf_desc->pages) {
2210                         buf_desc->cpu_addr =
2211                                 (void *)page_address(buf_desc->pages);
2212                         buf_desc->len = bufsize;
2213                         buf_desc->is_vm = false;
2214                         break;
2215                 }
2216                 if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
2217                         goto out;
2218                 fallthrough;    // try virtually continguous buf
2219         case SMCR_VIRT_CONT_BUFS:
2220                 buf_desc->order = get_order(bufsize);
2221                 buf_desc->cpu_addr = vzalloc(PAGE_SIZE << buf_desc->order);
2222                 if (!buf_desc->cpu_addr)
2223                         goto out;
2224                 buf_desc->pages = NULL;
2225                 buf_desc->len = bufsize;
2226                 buf_desc->is_vm = true;
2227                 break;
2228         }
2229         return buf_desc;
2230
2231 out:
2232         kfree(buf_desc);
2233         return ERR_PTR(-EAGAIN);
2234 }
2235
2236 /* map buf_desc on all usable links,
2237  * unused buffers stay mapped as long as the link is up
2238  */
2239 static int smcr_buf_map_usable_links(struct smc_link_group *lgr,
2240                                      struct smc_buf_desc *buf_desc, bool is_rmb)
2241 {
2242         int i, rc = 0, cnt = 0;
2243
2244         /* protect against parallel link reconfiguration */
2245         mutex_lock(&lgr->llc_conf_mutex);
2246         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2247                 struct smc_link *lnk = &lgr->lnk[i];
2248
2249                 if (!smc_link_usable(lnk))
2250                         continue;
2251                 if (smcr_buf_map_link(buf_desc, is_rmb, lnk)) {
2252                         rc = -ENOMEM;
2253                         goto out;
2254                 }
2255                 cnt++;
2256         }
2257 out:
2258         mutex_unlock(&lgr->llc_conf_mutex);
2259         if (!rc && !cnt)
2260                 rc = -EINVAL;
2261         return rc;
2262 }
2263
2264 static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr,
2265                                                 bool is_dmb, int bufsize)
2266 {
2267         struct smc_buf_desc *buf_desc;
2268         int rc;
2269
2270         /* try to alloc a new DMB */
2271         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
2272         if (!buf_desc)
2273                 return ERR_PTR(-ENOMEM);
2274         if (is_dmb) {
2275                 rc = smc_ism_register_dmb(lgr, bufsize, buf_desc);
2276                 if (rc) {
2277                         kfree(buf_desc);
2278                         if (rc == -ENOMEM)
2279                                 return ERR_PTR(-EAGAIN);
2280                         if (rc == -ENOSPC)
2281                                 return ERR_PTR(-ENOSPC);
2282                         return ERR_PTR(-EIO);
2283                 }
2284                 buf_desc->pages = virt_to_page(buf_desc->cpu_addr);
2285                 /* CDC header stored in buf. So, pretend it was smaller */
2286                 buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg);
2287         } else {
2288                 buf_desc->cpu_addr = kzalloc(bufsize, GFP_KERNEL |
2289                                              __GFP_NOWARN | __GFP_NORETRY |
2290                                              __GFP_NOMEMALLOC);
2291                 if (!buf_desc->cpu_addr) {
2292                         kfree(buf_desc);
2293                         return ERR_PTR(-EAGAIN);
2294                 }
2295                 buf_desc->len = bufsize;
2296         }
2297         return buf_desc;
2298 }
2299
2300 static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb)
2301 {
2302         struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM);
2303         struct smc_connection *conn = &smc->conn;
2304         struct smc_link_group *lgr = conn->lgr;
2305         struct list_head *buf_list;
2306         int bufsize, bufsize_short;
2307         bool is_dgraded = false;
2308         struct mutex *lock;     /* lock buffer list */
2309         int sk_buf_size;
2310
2311         if (is_rmb)
2312                 /* use socket recv buffer size (w/o overhead) as start value */
2313                 sk_buf_size = smc->sk.sk_rcvbuf;
2314         else
2315                 /* use socket send buffer size (w/o overhead) as start value */
2316                 sk_buf_size = smc->sk.sk_sndbuf;
2317
2318         for (bufsize_short = smc_compress_bufsize(sk_buf_size, is_smcd, is_rmb);
2319              bufsize_short >= 0; bufsize_short--) {
2320                 if (is_rmb) {
2321                         lock = &lgr->rmbs_lock;
2322                         buf_list = &lgr->rmbs[bufsize_short];
2323                 } else {
2324                         lock = &lgr->sndbufs_lock;
2325                         buf_list = &lgr->sndbufs[bufsize_short];
2326                 }
2327                 bufsize = smc_uncompress_bufsize(bufsize_short);
2328
2329                 /* check for reusable slot in the link group */
2330                 buf_desc = smc_buf_get_slot(bufsize_short, lock, buf_list);
2331                 if (buf_desc) {
2332                         buf_desc->is_dma_need_sync = 0;
2333                         SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
2334                         SMC_STAT_BUF_REUSE(smc, is_smcd, is_rmb);
2335                         break; /* found reusable slot */
2336                 }
2337
2338                 if (is_smcd)
2339                         buf_desc = smcd_new_buf_create(lgr, is_rmb, bufsize);
2340                 else
2341                         buf_desc = smcr_new_buf_create(lgr, is_rmb, bufsize);
2342
2343                 if (PTR_ERR(buf_desc) == -ENOMEM)
2344                         break;
2345                 if (IS_ERR(buf_desc)) {
2346                         if (!is_dgraded) {
2347                                 is_dgraded = true;
2348                                 SMC_STAT_RMB_DOWNGRADED(smc, is_smcd, is_rmb);
2349                         }
2350                         continue;
2351                 }
2352
2353                 SMC_STAT_RMB_ALLOC(smc, is_smcd, is_rmb);
2354                 SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
2355                 buf_desc->used = 1;
2356                 mutex_lock(lock);
2357                 list_add(&buf_desc->list, buf_list);
2358                 mutex_unlock(lock);
2359                 break; /* found */
2360         }
2361
2362         if (IS_ERR(buf_desc))
2363                 return PTR_ERR(buf_desc);
2364
2365         if (!is_smcd) {
2366                 if (smcr_buf_map_usable_links(lgr, buf_desc, is_rmb)) {
2367                         smcr_buf_unuse(buf_desc, is_rmb, lgr);
2368                         return -ENOMEM;
2369                 }
2370         }
2371
2372         if (is_rmb) {
2373                 conn->rmb_desc = buf_desc;
2374                 conn->rmbe_size_short = bufsize_short;
2375                 smc->sk.sk_rcvbuf = bufsize;
2376                 atomic_set(&conn->bytes_to_rcv, 0);
2377                 conn->rmbe_update_limit =
2378                         smc_rmb_wnd_update_limit(buf_desc->len);
2379                 if (is_smcd)
2380                         smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */
2381         } else {
2382                 conn->sndbuf_desc = buf_desc;
2383                 smc->sk.sk_sndbuf = bufsize;
2384                 atomic_set(&conn->sndbuf_space, bufsize);
2385         }
2386         return 0;
2387 }
2388
2389 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
2390 {
2391         if (!conn->sndbuf_desc->is_dma_need_sync)
2392                 return;
2393         if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd ||
2394             !smc_link_active(conn->lnk))
2395                 return;
2396         smc_ib_sync_sg_for_device(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
2397 }
2398
2399 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
2400 {
2401         int i;
2402
2403         if (!conn->rmb_desc->is_dma_need_sync)
2404                 return;
2405         if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd)
2406                 return;
2407         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2408                 if (!smc_link_active(&conn->lgr->lnk[i]))
2409                         continue;
2410                 smc_ib_sync_sg_for_cpu(&conn->lgr->lnk[i], conn->rmb_desc,
2411                                        DMA_FROM_DEVICE);
2412         }
2413 }
2414
2415 /* create the send and receive buffer for an SMC socket;
2416  * receive buffers are called RMBs;
2417  * (even though the SMC protocol allows more than one RMB-element per RMB,
2418  * the Linux implementation uses just one RMB-element per RMB, i.e. uses an
2419  * extra RMB for every connection in a link group
2420  */
2421 int smc_buf_create(struct smc_sock *smc, bool is_smcd)
2422 {
2423         int rc;
2424
2425         /* create send buffer */
2426         rc = __smc_buf_create(smc, is_smcd, false);
2427         if (rc)
2428                 return rc;
2429         /* create rmb */
2430         rc = __smc_buf_create(smc, is_smcd, true);
2431         if (rc) {
2432                 mutex_lock(&smc->conn.lgr->sndbufs_lock);
2433                 list_del(&smc->conn.sndbuf_desc->list);
2434                 mutex_unlock(&smc->conn.lgr->sndbufs_lock);
2435                 smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc);
2436                 smc->conn.sndbuf_desc = NULL;
2437         }
2438         return rc;
2439 }
2440
2441 static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
2442 {
2443         int i;
2444
2445         for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) {
2446                 if (!test_and_set_bit(i, lgr->rtokens_used_mask))
2447                         return i;
2448         }
2449         return -ENOSPC;
2450 }
2451
2452 static int smc_rtoken_find_by_link(struct smc_link_group *lgr, int lnk_idx,
2453                                    u32 rkey)
2454 {
2455         int i;
2456
2457         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2458                 if (test_bit(i, lgr->rtokens_used_mask) &&
2459                     lgr->rtokens[i][lnk_idx].rkey == rkey)
2460                         return i;
2461         }
2462         return -ENOENT;
2463 }
2464
2465 /* set rtoken for a new link to an existing rmb */
2466 void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
2467                     __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey)
2468 {
2469         int rtok_idx;
2470
2471         rtok_idx = smc_rtoken_find_by_link(lgr, link_idx, ntohl(nw_rkey_known));
2472         if (rtok_idx == -ENOENT)
2473                 return;
2474         lgr->rtokens[rtok_idx][link_idx_new].rkey = ntohl(nw_rkey);
2475         lgr->rtokens[rtok_idx][link_idx_new].dma_addr = be64_to_cpu(nw_vaddr);
2476 }
2477
2478 /* set rtoken for a new link whose link_id is given */
2479 void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
2480                      __be64 nw_vaddr, __be32 nw_rkey)
2481 {
2482         u64 dma_addr = be64_to_cpu(nw_vaddr);
2483         u32 rkey = ntohl(nw_rkey);
2484         bool found = false;
2485         int link_idx;
2486
2487         for (link_idx = 0; link_idx < SMC_LINKS_PER_LGR_MAX; link_idx++) {
2488                 if (lgr->lnk[link_idx].link_id == link_id) {
2489                         found = true;
2490                         break;
2491                 }
2492         }
2493         if (!found)
2494                 return;
2495         lgr->rtokens[rtok_idx][link_idx].rkey = rkey;
2496         lgr->rtokens[rtok_idx][link_idx].dma_addr = dma_addr;
2497 }
2498
2499 /* add a new rtoken from peer */
2500 int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey)
2501 {
2502         struct smc_link_group *lgr = smc_get_lgr(lnk);
2503         u64 dma_addr = be64_to_cpu(nw_vaddr);
2504         u32 rkey = ntohl(nw_rkey);
2505         int i;
2506
2507         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2508                 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2509                     lgr->rtokens[i][lnk->link_idx].dma_addr == dma_addr &&
2510                     test_bit(i, lgr->rtokens_used_mask)) {
2511                         /* already in list */
2512                         return i;
2513                 }
2514         }
2515         i = smc_rmb_reserve_rtoken_idx(lgr);
2516         if (i < 0)
2517                 return i;
2518         lgr->rtokens[i][lnk->link_idx].rkey = rkey;
2519         lgr->rtokens[i][lnk->link_idx].dma_addr = dma_addr;
2520         return i;
2521 }
2522
2523 /* delete an rtoken from all links */
2524 int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey)
2525 {
2526         struct smc_link_group *lgr = smc_get_lgr(lnk);
2527         u32 rkey = ntohl(nw_rkey);
2528         int i, j;
2529
2530         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2531                 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2532                     test_bit(i, lgr->rtokens_used_mask)) {
2533                         for (j = 0; j < SMC_LINKS_PER_LGR_MAX; j++) {
2534                                 lgr->rtokens[i][j].rkey = 0;
2535                                 lgr->rtokens[i][j].dma_addr = 0;
2536                         }
2537                         clear_bit(i, lgr->rtokens_used_mask);
2538                         return 0;
2539                 }
2540         }
2541         return -ENOENT;
2542 }
2543
2544 /* save rkey and dma_addr received from peer during clc handshake */
2545 int smc_rmb_rtoken_handling(struct smc_connection *conn,
2546                             struct smc_link *lnk,
2547                             struct smc_clc_msg_accept_confirm *clc)
2548 {
2549         conn->rtoken_idx = smc_rtoken_add(lnk, clc->r0.rmb_dma_addr,
2550                                           clc->r0.rmb_rkey);
2551         if (conn->rtoken_idx < 0)
2552                 return conn->rtoken_idx;
2553         return 0;
2554 }
2555
2556 static void smc_core_going_away(void)
2557 {
2558         struct smc_ib_device *smcibdev;
2559         struct smcd_dev *smcd;
2560
2561         mutex_lock(&smc_ib_devices.mutex);
2562         list_for_each_entry(smcibdev, &smc_ib_devices.list, list) {
2563                 int i;
2564
2565                 for (i = 0; i < SMC_MAX_PORTS; i++)
2566                         set_bit(i, smcibdev->ports_going_away);
2567         }
2568         mutex_unlock(&smc_ib_devices.mutex);
2569
2570         mutex_lock(&smcd_dev_list.mutex);
2571         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2572                 smcd->going_away = 1;
2573         }
2574         mutex_unlock(&smcd_dev_list.mutex);
2575 }
2576
2577 /* Clean up all SMC link groups */
2578 static void smc_lgrs_shutdown(void)
2579 {
2580         struct smcd_dev *smcd;
2581
2582         smc_core_going_away();
2583
2584         smc_smcr_terminate_all(NULL);
2585
2586         mutex_lock(&smcd_dev_list.mutex);
2587         list_for_each_entry(smcd, &smcd_dev_list.list, list)
2588                 smc_smcd_terminate_all(smcd);
2589         mutex_unlock(&smcd_dev_list.mutex);
2590 }
2591
2592 static int smc_core_reboot_event(struct notifier_block *this,
2593                                  unsigned long event, void *ptr)
2594 {
2595         smc_lgrs_shutdown();
2596         smc_ib_unregister_client();
2597         return 0;
2598 }
2599
2600 static struct notifier_block smc_reboot_notifier = {
2601         .notifier_call = smc_core_reboot_event,
2602 };
2603
2604 int __init smc_core_init(void)
2605 {
2606         return register_reboot_notifier(&smc_reboot_notifier);
2607 }
2608
2609 /* Called (from smc_exit) when module is removed */
2610 void smc_core_exit(void)
2611 {
2612         unregister_reboot_notifier(&smc_reboot_notifier);
2613         smc_lgrs_shutdown();
2614 }