net/smc/smc_core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
   4  *
   5  *  Basic Transport Functions exploiting Infiniband API
   6  *
   7  *  Copyright IBM Corp. 2016
   8  *
   9  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
  10  */
  11
  12 #include <linux/socket.h>
  13 #include <linux/if_vlan.h>
  14 #include <linux/random.h>
  15 #include <linux/workqueue.h>
  16 #include <linux/wait.h>
  17 #include <linux/reboot.h>
  18 #include <linux/mutex.h>
  19 #include <linux/list.h>
  20 #include <linux/smc.h>
  21 #include <net/tcp.h>
  22 #include <net/sock.h>
  23 #include <rdma/ib_verbs.h>
  24 #include <rdma/ib_cache.h>
  25
  26 #include "smc.h"
  27 #include "smc_clc.h"
  28 #include "smc_core.h"
  29 #include "smc_ib.h"
  30 #include "smc_wr.h"
  31 #include "smc_llc.h"
  32 #include "smc_cdc.h"
  33 #include "smc_close.h"
  34 #include "smc_ism.h"
  35 #include "smc_netlink.h"
  36 #include "smc_stats.h"
  37 #include "smc_tracepoint.h"
  38
  39 #define SMC_LGR_NUM_INCR                256
  40 #define SMC_LGR_FREE_DELAY_SERV         (600 * HZ)
  41 #define SMC_LGR_FREE_DELAY_CLNT         (SMC_LGR_FREE_DELAY_SERV + 10 * HZ)
  42
  43 struct smc_lgr_list smc_lgr_list = {    /* established link groups */
  44         .lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
  45         .list = LIST_HEAD_INIT(smc_lgr_list.list),
  46         .num = 0,
  47 };
  48
  49 static atomic_t lgr_cnt = ATOMIC_INIT(0); /* number of existing link groups */
  50 static DECLARE_WAIT_QUEUE_HEAD(lgrs_deleted);
  51
  52 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
  53                          struct smc_buf_desc *buf_desc);
  54 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft);
  55
  56 static void smc_link_down_work(struct work_struct *work);
  57
  58 /* return head of link group list and its lock for a given link group */
  59 static inline struct list_head *smc_lgr_list_head(struct smc_link_group *lgr,
  60                                                   spinlock_t **lgr_lock)
  61 {
  62         if (lgr->is_smcd) {
  63                 *lgr_lock = &lgr->smcd->lgr_lock;
  64                 return &lgr->smcd->lgr_list;
  65         }
  66
  67         *lgr_lock = &smc_lgr_list.lock;
  68         return &smc_lgr_list.list;
  69 }
  70
  71 static void smc_ibdev_cnt_inc(struct smc_link *lnk)
  72 {
  73         atomic_inc(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
  74 }
  75
  76 static void smc_ibdev_cnt_dec(struct smc_link *lnk)
  77 {
  78         atomic_dec(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
  79 }
  80
  81 static void smc_lgr_schedule_free_work(struct smc_link_group *lgr)
  82 {
  83         /* client link group creation always follows the server link group
  84          * creation. For client use a somewhat higher removal delay time,
  85          * otherwise there is a risk of out-of-sync link groups.
  86          */
  87         if (!lgr->freeing) {
  88                 mod_delayed_work(system_wq, &lgr->free_work,
  89                                  (!lgr->is_smcd && lgr->role == SMC_CLNT) ?
  90                                                 SMC_LGR_FREE_DELAY_CLNT :
  91                                                 SMC_LGR_FREE_DELAY_SERV);
  92         }
  93 }
  94
  95 /* Register connection's alert token in our lookup structure.
  96  * To use rbtrees we have to implement our own insert core.
  97  * Requires @conns_lock
  98  * @smc         connection to register
  99  * Returns 0 on success, != otherwise.
 100  */
 101 static void smc_lgr_add_alert_token(struct smc_connection *conn)
 102 {
 103         struct rb_node **link, *parent = NULL;
 104         u32 token = conn->alert_token_local;
 105
 106         link = &conn->lgr->conns_all.rb_node;
 107         while (*link) {
 108                 struct smc_connection *cur = rb_entry(*link,
 109                                         struct smc_connection, alert_node);
 110
 111                 parent = *link;
 112                 if (cur->alert_token_local > token)
 113                         link = &parent->rb_left;
 114                 else
 115                         link = &parent->rb_right;
 116         }
 117         /* Put the new node there */
 118         rb_link_node(&conn->alert_node, parent, link);
 119         rb_insert_color(&conn->alert_node, &conn->lgr->conns_all);
 120 }
 121
 122 /* assign an SMC-R link to the connection */
 123 static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first)
 124 {
 125         enum smc_link_state expected = first ? SMC_LNK_ACTIVATING :
 126                                        SMC_LNK_ACTIVE;
 127         int i, j;
 128
 129         /* do link balancing */
 130         conn->lnk = NULL;       /* reset conn->lnk first */
 131         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 132                 struct smc_link *lnk = &conn->lgr->lnk[i];
 133
 134                 if (lnk->state != expected || lnk->link_is_asym)
 135                         continue;
 136                 if (conn->lgr->role == SMC_CLNT) {
 137                         conn->lnk = lnk; /* temporary, SMC server assigns link*/
 138                         break;
 139                 }
 140                 if (conn->lgr->conns_num % 2) {
 141                         for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) {
 142                                 struct smc_link *lnk2;
 143
 144                                 lnk2 = &conn->lgr->lnk[j];
 145                                 if (lnk2->state == expected &&
 146                                     !lnk2->link_is_asym) {
 147                                         conn->lnk = lnk2;
 148                                         break;
 149                                 }
 150                         }
 151                 }
 152                 if (!conn->lnk)
 153                         conn->lnk = lnk;
 154                 break;
 155         }
 156         if (!conn->lnk)
 157                 return SMC_CLC_DECL_NOACTLINK;
 158         atomic_inc(&conn->lnk->conn_cnt);
 159         return 0;
 160 }
 161
 162 /* Register connection in link group by assigning an alert token
 163  * registered in a search tree.
 164  * Requires @conns_lock
 165  * Note that '0' is a reserved value and not assigned.
 166  */
 167 static int smc_lgr_register_conn(struct smc_connection *conn, bool first)
 168 {
 169         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 170         static atomic_t nexttoken = ATOMIC_INIT(0);
 171         int rc;
 172
 173         if (!conn->lgr->is_smcd) {
 174                 rc = smcr_lgr_conn_assign_link(conn, first);
 175                 if (rc) {
 176                         conn->lgr = NULL;
 177                         return rc;
 178                 }
 179         }
 180         /* find a new alert_token_local value not yet used by some connection
 181          * in this link group
 182          */
 183         sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */
 184         while (!conn->alert_token_local) {
 185                 conn->alert_token_local = atomic_inc_return(&nexttoken);
 186                 if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr))
 187                         conn->alert_token_local = 0;
 188         }
 189         smc_lgr_add_alert_token(conn);
 190         conn->lgr->conns_num++;
 191         return 0;
 192 }
 193
 194 /* Unregister connection and reset the alert token of the given connection<
 195  */
 196 static void __smc_lgr_unregister_conn(struct smc_connection *conn)
 197 {
 198         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 199         struct smc_link_group *lgr = conn->lgr;
 200
 201         rb_erase(&conn->alert_node, &lgr->conns_all);
 202         if (conn->lnk)
 203                 atomic_dec(&conn->lnk->conn_cnt);
 204         lgr->conns_num--;
 205         conn->alert_token_local = 0;
 206         sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
 207 }
 208
 209 /* Unregister connection from lgr
 210  */
 211 static void smc_lgr_unregister_conn(struct smc_connection *conn)
 212 {
 213         struct smc_link_group *lgr = conn->lgr;
 214
 215         if (!smc_conn_lgr_valid(conn))
 216                 return;
 217         write_lock_bh(&lgr->conns_lock);
 218         if (conn->alert_token_local) {
 219                 __smc_lgr_unregister_conn(conn);
 220         }
 221         write_unlock_bh(&lgr->conns_lock);
 222 }
 223
 224 int smc_nl_get_sys_info(struct sk_buff *skb, struct netlink_callback *cb)
 225 {
 226         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 227         char hostname[SMC_MAX_HOSTNAME_LEN + 1];
 228         char smc_seid[SMC_MAX_EID_LEN + 1];
 229         struct nlattr *attrs;
 230         u8 *seid = NULL;
 231         u8 *host = NULL;
 232         void *nlh;
 233
 234         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 235                           &smc_gen_nl_family, NLM_F_MULTI,
 236                           SMC_NETLINK_GET_SYS_INFO);
 237         if (!nlh)
 238                 goto errmsg;
 239         if (cb_ctx->pos[0])
 240                 goto errout;
 241         attrs = nla_nest_start(skb, SMC_GEN_SYS_INFO);
 242         if (!attrs)
 243                 goto errout;
 244         if (nla_put_u8(skb, SMC_NLA_SYS_VER, SMC_V2))
 245                 goto errattr;
 246         if (nla_put_u8(skb, SMC_NLA_SYS_REL, SMC_RELEASE))
 247                 goto errattr;
 248         if (nla_put_u8(skb, SMC_NLA_SYS_IS_ISM_V2, smc_ism_is_v2_capable()))
 249                 goto errattr;
 250         if (nla_put_u8(skb, SMC_NLA_SYS_IS_SMCR_V2, true))
 251                 goto errattr;
 252         smc_clc_get_hostname(&host);
 253         if (host) {
 254                 memcpy(hostname, host, SMC_MAX_HOSTNAME_LEN);
 255                 hostname[SMC_MAX_HOSTNAME_LEN] = 0;
 256                 if (nla_put_string(skb, SMC_NLA_SYS_LOCAL_HOST, hostname))
 257                         goto errattr;
 258         }
 259         if (smc_ism_is_v2_capable()) {
 260                 smc_ism_get_system_eid(&seid);
 261                 memcpy(smc_seid, seid, SMC_MAX_EID_LEN);
 262                 smc_seid[SMC_MAX_EID_LEN] = 0;
 263                 if (nla_put_string(skb, SMC_NLA_SYS_SEID, smc_seid))
 264                         goto errattr;
 265         }
 266         nla_nest_end(skb, attrs);
 267         genlmsg_end(skb, nlh);
 268         cb_ctx->pos[0] = 1;
 269         return skb->len;
 270
 271 errattr:
 272         nla_nest_cancel(skb, attrs);
 273 errout:
 274         genlmsg_cancel(skb, nlh);
 275 errmsg:
 276         return skb->len;
 277 }
 278
 279 /* Fill SMC_NLA_LGR_D_V2_COMMON/SMC_NLA_LGR_R_V2_COMMON nested attributes */
 280 static int smc_nl_fill_lgr_v2_common(struct smc_link_group *lgr,
 281                                      struct sk_buff *skb,
 282                                      struct netlink_callback *cb,
 283                                      struct nlattr *v2_attrs)
 284 {
 285         char smc_host[SMC_MAX_HOSTNAME_LEN + 1];
 286         char smc_eid[SMC_MAX_EID_LEN + 1];
 287
 288         if (nla_put_u8(skb, SMC_NLA_LGR_V2_VER, lgr->smc_version))
 289                 goto errv2attr;
 290         if (nla_put_u8(skb, SMC_NLA_LGR_V2_REL, lgr->peer_smc_release))
 291                 goto errv2attr;
 292         if (nla_put_u8(skb, SMC_NLA_LGR_V2_OS, lgr->peer_os))
 293                 goto errv2attr;
 294         memcpy(smc_host, lgr->peer_hostname, SMC_MAX_HOSTNAME_LEN);
 295         smc_host[SMC_MAX_HOSTNAME_LEN] = 0;
 296         if (nla_put_string(skb, SMC_NLA_LGR_V2_PEER_HOST, smc_host))
 297                 goto errv2attr;
 298         memcpy(smc_eid, lgr->negotiated_eid, SMC_MAX_EID_LEN);
 299         smc_eid[SMC_MAX_EID_LEN] = 0;
 300         if (nla_put_string(skb, SMC_NLA_LGR_V2_NEG_EID, smc_eid))
 301                 goto errv2attr;
 302
 303         nla_nest_end(skb, v2_attrs);
 304         return 0;
 305
 306 errv2attr:
 307         nla_nest_cancel(skb, v2_attrs);
 308         return -EMSGSIZE;
 309 }
 310
 311 static int smc_nl_fill_smcr_lgr_v2(struct smc_link_group *lgr,
 312                                    struct sk_buff *skb,
 313                                    struct netlink_callback *cb)
 314 {
 315         struct nlattr *v2_attrs;
 316
 317         v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2);
 318         if (!v2_attrs)
 319                 goto errattr;
 320         if (nla_put_u8(skb, SMC_NLA_LGR_R_V2_DIRECT, !lgr->uses_gateway))
 321                 goto errv2attr;
 322
 323         nla_nest_end(skb, v2_attrs);
 324         return 0;
 325
 326 errv2attr:
 327         nla_nest_cancel(skb, v2_attrs);
 328 errattr:
 329         return -EMSGSIZE;
 330 }
 331
 332 static int smc_nl_fill_lgr(struct smc_link_group *lgr,
 333                            struct sk_buff *skb,
 334                            struct netlink_callback *cb)
 335 {
 336         char smc_target[SMC_MAX_PNETID_LEN + 1];
 337         struct nlattr *attrs, *v2_attrs;
 338
 339         attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCR);
 340         if (!attrs)
 341                 goto errout;
 342
 343         if (nla_put_u32(skb, SMC_NLA_LGR_R_ID, *((u32 *)&lgr->id)))
 344                 goto errattr;
 345         if (nla_put_u32(skb, SMC_NLA_LGR_R_CONNS_NUM, lgr->conns_num))
 346                 goto errattr;
 347         if (nla_put_u8(skb, SMC_NLA_LGR_R_ROLE, lgr->role))
 348                 goto errattr;
 349         if (nla_put_u8(skb, SMC_NLA_LGR_R_TYPE, lgr->type))
 350                 goto errattr;
 351         if (nla_put_u8(skb, SMC_NLA_LGR_R_BUF_TYPE, lgr->buf_type))
 352                 goto errattr;
 353         if (nla_put_u8(skb, SMC_NLA_LGR_R_VLAN_ID, lgr->vlan_id))
 354                 goto errattr;
 355         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_R_NET_COOKIE,
 356                               lgr->net->net_cookie, SMC_NLA_LGR_R_PAD))
 357                 goto errattr;
 358         memcpy(smc_target, lgr->pnet_id, SMC_MAX_PNETID_LEN);
 359         smc_target[SMC_MAX_PNETID_LEN] = 0;
 360         if (nla_put_string(skb, SMC_NLA_LGR_R_PNETID, smc_target))
 361                 goto errattr;
 362         if (lgr->smc_version > SMC_V1) {
 363                 v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_R_V2_COMMON);
 364                 if (!v2_attrs)
 365                         goto errattr;
 366                 if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
 367                         goto errattr;
 368                 if (smc_nl_fill_smcr_lgr_v2(lgr, skb, cb))
 369                         goto errattr;
 370         }
 371
 372         nla_nest_end(skb, attrs);
 373         return 0;
 374 errattr:
 375         nla_nest_cancel(skb, attrs);
 376 errout:
 377         return -EMSGSIZE;
 378 }
 379
 380 static int smc_nl_fill_lgr_link(struct smc_link_group *lgr,
 381                                 struct smc_link *link,
 382                                 struct sk_buff *skb,
 383                                 struct netlink_callback *cb)
 384 {
 385         char smc_ibname[IB_DEVICE_NAME_MAX];
 386         u8 smc_gid_target[41];
 387         struct nlattr *attrs;
 388         u32 link_uid = 0;
 389         void *nlh;
 390
 391         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 392                           &smc_gen_nl_family, NLM_F_MULTI,
 393                           SMC_NETLINK_GET_LINK_SMCR);
 394         if (!nlh)
 395                 goto errmsg;
 396
 397         attrs = nla_nest_start(skb, SMC_GEN_LINK_SMCR);
 398         if (!attrs)
 399                 goto errout;
 400
 401         if (nla_put_u8(skb, SMC_NLA_LINK_ID, link->link_id))
 402                 goto errattr;
 403         if (nla_put_u32(skb, SMC_NLA_LINK_STATE, link->state))
 404                 goto errattr;
 405         if (nla_put_u32(skb, SMC_NLA_LINK_CONN_CNT,
 406                         atomic_read(&link->conn_cnt)))
 407                 goto errattr;
 408         if (nla_put_u8(skb, SMC_NLA_LINK_IB_PORT, link->ibport))
 409                 goto errattr;
 410         if (nla_put_u32(skb, SMC_NLA_LINK_NET_DEV, link->ndev_ifidx))
 411                 goto errattr;
 412         snprintf(smc_ibname, sizeof(smc_ibname), "%s", link->ibname);
 413         if (nla_put_string(skb, SMC_NLA_LINK_IB_DEV, smc_ibname))
 414                 goto errattr;
 415         memcpy(&link_uid, link->link_uid, sizeof(link_uid));
 416         if (nla_put_u32(skb, SMC_NLA_LINK_UID, link_uid))
 417                 goto errattr;
 418         memcpy(&link_uid, link->peer_link_uid, sizeof(link_uid));
 419         if (nla_put_u32(skb, SMC_NLA_LINK_PEER_UID, link_uid))
 420                 goto errattr;
 421         memset(smc_gid_target, 0, sizeof(smc_gid_target));
 422         smc_gid_be16_convert(smc_gid_target, link->gid);
 423         if (nla_put_string(skb, SMC_NLA_LINK_GID, smc_gid_target))
 424                 goto errattr;
 425         memset(smc_gid_target, 0, sizeof(smc_gid_target));
 426         smc_gid_be16_convert(smc_gid_target, link->peer_gid);
 427         if (nla_put_string(skb, SMC_NLA_LINK_PEER_GID, smc_gid_target))
 428                 goto errattr;
 429
 430         nla_nest_end(skb, attrs);
 431         genlmsg_end(skb, nlh);
 432         return 0;
 433 errattr:
 434         nla_nest_cancel(skb, attrs);
 435 errout:
 436         genlmsg_cancel(skb, nlh);
 437 errmsg:
 438         return -EMSGSIZE;
 439 }
 440
 441 static int smc_nl_handle_lgr(struct smc_link_group *lgr,
 442                              struct sk_buff *skb,
 443                              struct netlink_callback *cb,
 444                              bool list_links)
 445 {
 446         void *nlh;
 447         int i;
 448
 449         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 450                           &smc_gen_nl_family, NLM_F_MULTI,
 451                           SMC_NETLINK_GET_LGR_SMCR);
 452         if (!nlh)
 453                 goto errmsg;
 454         if (smc_nl_fill_lgr(lgr, skb, cb))
 455                 goto errout;
 456
 457         genlmsg_end(skb, nlh);
 458         if (!list_links)
 459                 goto out;
 460         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 461                 if (!smc_link_usable(&lgr->lnk[i]))
 462                         continue;
 463                 if (smc_nl_fill_lgr_link(lgr, &lgr->lnk[i], skb, cb))
 464                         goto errout;
 465         }
 466 out:
 467         return 0;
 468
 469 errout:
 470         genlmsg_cancel(skb, nlh);
 471 errmsg:
 472         return -EMSGSIZE;
 473 }
 474
 475 static void smc_nl_fill_lgr_list(struct smc_lgr_list *smc_lgr,
 476                                  struct sk_buff *skb,
 477                                  struct netlink_callback *cb,
 478                                  bool list_links)
 479 {
 480         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 481         struct smc_link_group *lgr;
 482         int snum = cb_ctx->pos[0];
 483         int num = 0;
 484
 485         spin_lock_bh(&smc_lgr->lock);
 486         list_for_each_entry(lgr, &smc_lgr->list, list) {
 487                 if (num < snum)
 488                         goto next;
 489                 if (smc_nl_handle_lgr(lgr, skb, cb, list_links))
 490                         goto errout;
 491 next:
 492                 num++;
 493         }
 494 errout:
 495         spin_unlock_bh(&smc_lgr->lock);
 496         cb_ctx->pos[0] = num;
 497 }
 498
 499 static int smc_nl_fill_smcd_lgr(struct smc_link_group *lgr,
 500                                 struct sk_buff *skb,
 501                                 struct netlink_callback *cb)
 502 {
 503         char smc_pnet[SMC_MAX_PNETID_LEN + 1];
 504         struct smcd_dev *smcd = lgr->smcd;
 505         struct nlattr *attrs;
 506         void *nlh;
 507
 508         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 509                           &smc_gen_nl_family, NLM_F_MULTI,
 510                           SMC_NETLINK_GET_LGR_SMCD);
 511         if (!nlh)
 512                 goto errmsg;
 513
 514         attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCD);
 515         if (!attrs)
 516                 goto errout;
 517
 518         if (nla_put_u32(skb, SMC_NLA_LGR_D_ID, *((u32 *)&lgr->id)))
 519                 goto errattr;
 520         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_GID,
 521                               smcd->ops->get_local_gid(smcd),
 522                                   SMC_NLA_LGR_D_PAD))
 523                 goto errattr;
 524         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_GID, lgr->peer_gid,
 525                               SMC_NLA_LGR_D_PAD))
 526                 goto errattr;
 527         if (nla_put_u8(skb, SMC_NLA_LGR_D_VLAN_ID, lgr->vlan_id))
 528                 goto errattr;
 529         if (nla_put_u32(skb, SMC_NLA_LGR_D_CONNS_NUM, lgr->conns_num))
 530                 goto errattr;
 531         if (nla_put_u32(skb, SMC_NLA_LGR_D_CHID, smc_ism_get_chid(lgr->smcd)))
 532                 goto errattr;
 533         memcpy(smc_pnet, lgr->smcd->pnetid, SMC_MAX_PNETID_LEN);
 534         smc_pnet[SMC_MAX_PNETID_LEN] = 0;
 535         if (nla_put_string(skb, SMC_NLA_LGR_D_PNETID, smc_pnet))
 536                 goto errattr;
 537         if (lgr->smc_version > SMC_V1) {
 538                 struct nlattr *v2_attrs;
 539
 540                 v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_D_V2_COMMON);
 541                 if (!v2_attrs)
 542                         goto errattr;
 543                 if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
 544                         goto errattr;
 545         }
 546         nla_nest_end(skb, attrs);
 547         genlmsg_end(skb, nlh);
 548         return 0;
 549
 550 errattr:
 551         nla_nest_cancel(skb, attrs);
 552 errout:
 553         genlmsg_cancel(skb, nlh);
 554 errmsg:
 555         return -EMSGSIZE;
 556 }
 557
 558 static int smc_nl_handle_smcd_lgr(struct smcd_dev *dev,
 559                                   struct sk_buff *skb,
 560                                   struct netlink_callback *cb)
 561 {
 562         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 563         struct smc_link_group *lgr;
 564         int snum = cb_ctx->pos[1];
 565         int rc = 0, num = 0;
 566
 567         spin_lock_bh(&dev->lgr_lock);
 568         list_for_each_entry(lgr, &dev->lgr_list, list) {
 569                 if (!lgr->is_smcd)
 570                         continue;
 571                 if (num < snum)
 572                         goto next;
 573                 rc = smc_nl_fill_smcd_lgr(lgr, skb, cb);
 574                 if (rc)
 575                         goto errout;
 576 next:
 577                 num++;
 578         }
 579 errout:
 580         spin_unlock_bh(&dev->lgr_lock);
 581         cb_ctx->pos[1] = num;
 582         return rc;
 583 }
 584
 585 static int smc_nl_fill_smcd_dev(struct smcd_dev_list *dev_list,
 586                                 struct sk_buff *skb,
 587                                 struct netlink_callback *cb)
 588 {
 589         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 590         struct smcd_dev *smcd_dev;
 591         int snum = cb_ctx->pos[0];
 592         int rc = 0, num = 0;
 593
 594         mutex_lock(&dev_list->mutex);
 595         list_for_each_entry(smcd_dev, &dev_list->list, list) {
 596                 if (list_empty(&smcd_dev->lgr_list))
 597                         continue;
 598                 if (num < snum)
 599                         goto next;
 600                 rc = smc_nl_handle_smcd_lgr(smcd_dev, skb, cb);
 601                 if (rc)
 602                         goto errout;
 603 next:
 604                 num++;
 605         }
 606 errout:
 607         mutex_unlock(&dev_list->mutex);
 608         cb_ctx->pos[0] = num;
 609         return rc;
 610 }
 611
 612 int smcr_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
 613 {
 614         bool list_links = false;
 615
 616         smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
 617         return skb->len;
 618 }
 619
 620 int smcr_nl_get_link(struct sk_buff *skb, struct netlink_callback *cb)
 621 {
 622         bool list_links = true;
 623
 624         smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
 625         return skb->len;
 626 }
 627
 628 int smcd_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
 629 {
 630         smc_nl_fill_smcd_dev(&smcd_dev_list, skb, cb);
 631         return skb->len;
 632 }
 633
 634 void smc_lgr_cleanup_early(struct smc_link_group *lgr)
 635 {
 636         spinlock_t *lgr_lock;
 637
 638         if (!lgr)
 639                 return;
 640
 641         smc_lgr_list_head(lgr, &lgr_lock);
 642         spin_lock_bh(lgr_lock);
 643         /* do not use this link group for new connections */
 644         if (!list_empty(&lgr->list))
 645                 list_del_init(&lgr->list);
 646         spin_unlock_bh(lgr_lock);
 647         __smc_lgr_terminate(lgr, true);
 648 }
 649
 650 static void smcr_lgr_link_deactivate_all(struct smc_link_group *lgr)
 651 {
 652         int i;
 653
 654         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 655                 struct smc_link *lnk = &lgr->lnk[i];
 656
 657                 if (smc_link_sendable(lnk))
 658                         lnk->state = SMC_LNK_INACTIVE;
 659         }
 660         wake_up_all(&lgr->llc_msg_waiter);
 661         wake_up_all(&lgr->llc_flow_waiter);
 662 }
 663
 664 static void smc_lgr_free(struct smc_link_group *lgr);
 665
 666 static void smc_lgr_free_work(struct work_struct *work)
 667 {
 668         struct smc_link_group *lgr = container_of(to_delayed_work(work),
 669                                                   struct smc_link_group,
 670                                                   free_work);
 671         spinlock_t *lgr_lock;
 672         bool conns;
 673
 674         smc_lgr_list_head(lgr, &lgr_lock);
 675         spin_lock_bh(lgr_lock);
 676         if (lgr->freeing) {
 677                 spin_unlock_bh(lgr_lock);
 678                 return;
 679         }
 680         read_lock_bh(&lgr->conns_lock);
 681         conns = RB_EMPTY_ROOT(&lgr->conns_all);
 682         read_unlock_bh(&lgr->conns_lock);
 683         if (!conns) { /* number of lgr connections is no longer zero */
 684                 spin_unlock_bh(lgr_lock);
 685                 return;
 686         }
 687         list_del_init(&lgr->list); /* remove from smc_lgr_list */
 688         lgr->freeing = 1; /* this instance does the freeing, no new schedule */
 689         spin_unlock_bh(lgr_lock);
 690         cancel_delayed_work(&lgr->free_work);
 691
 692         if (!lgr->is_smcd && !lgr->terminating)
 693                 smc_llc_send_link_delete_all(lgr, true,
 694                                              SMC_LLC_DEL_PROG_INIT_TERM);
 695         if (lgr->is_smcd && !lgr->terminating)
 696                 smc_ism_signal_shutdown(lgr);
 697         if (!lgr->is_smcd)
 698                 smcr_lgr_link_deactivate_all(lgr);
 699         smc_lgr_free(lgr);
 700 }
 701
 702 static void smc_lgr_terminate_work(struct work_struct *work)
 703 {
 704         struct smc_link_group *lgr = container_of(work, struct smc_link_group,
 705                                                   terminate_work);
 706
 707         __smc_lgr_terminate(lgr, true);
 708 }
 709
 710 /* return next unique link id for the lgr */
 711 static u8 smcr_next_link_id(struct smc_link_group *lgr)
 712 {
 713         u8 link_id;
 714         int i;
 715
 716         while (1) {
 717 again:
 718                 link_id = ++lgr->next_link_id;
 719                 if (!link_id)   /* skip zero as link_id */
 720                         link_id = ++lgr->next_link_id;
 721                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 722                         if (smc_link_usable(&lgr->lnk[i]) &&
 723                             lgr->lnk[i].link_id == link_id)
 724                                 goto again;
 725                 }
 726                 break;
 727         }
 728         return link_id;
 729 }
 730
 731 static void smcr_copy_dev_info_to_link(struct smc_link *link)
 732 {
 733         struct smc_ib_device *smcibdev = link->smcibdev;
 734
 735         snprintf(link->ibname, sizeof(link->ibname), "%s",
 736                  smcibdev->ibdev->name);
 737         link->ndev_ifidx = smcibdev->ndev_ifidx[link->ibport - 1];
 738 }
 739
 740 int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
 741                    u8 link_idx, struct smc_init_info *ini)
 742 {
 743         struct smc_ib_device *smcibdev;
 744         u8 rndvec[3];
 745         int rc;
 746
 747         if (lgr->smc_version == SMC_V2) {
 748                 lnk->smcibdev = ini->smcrv2.ib_dev_v2;
 749                 lnk->ibport = ini->smcrv2.ib_port_v2;
 750         } else {
 751                 lnk->smcibdev = ini->ib_dev;
 752                 lnk->ibport = ini->ib_port;
 753         }
 754         get_device(&lnk->smcibdev->ibdev->dev);
 755         atomic_inc(&lnk->smcibdev->lnk_cnt);
 756         refcount_set(&lnk->refcnt, 1); /* link refcnt is set to 1 */
 757         lnk->clearing = 0;
 758         lnk->path_mtu = lnk->smcibdev->pattr[lnk->ibport - 1].active_mtu;
 759         lnk->link_id = smcr_next_link_id(lgr);
 760         lnk->lgr = lgr;
 761         smc_lgr_hold(lgr); /* lgr_put in smcr_link_clear() */
 762         lnk->link_idx = link_idx;
 763         lnk->wr_rx_id_compl = 0;
 764         smc_ibdev_cnt_inc(lnk);
 765         smcr_copy_dev_info_to_link(lnk);
 766         atomic_set(&lnk->conn_cnt, 0);
 767         smc_llc_link_set_uid(lnk);
 768         INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
 769         if (!lnk->smcibdev->initialized) {
 770                 rc = (int)smc_ib_setup_per_ibdev(lnk->smcibdev);
 771                 if (rc)
 772                         goto out;
 773         }
 774         get_random_bytes(rndvec, sizeof(rndvec));
 775         lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) +
 776                 (rndvec[2] << 16);
 777         rc = smc_ib_determine_gid(lnk->smcibdev, lnk->ibport,
 778                                   ini->vlan_id, lnk->gid, &lnk->sgid_index,
 779                                   lgr->smc_version == SMC_V2 ?
 780                                                   &ini->smcrv2 : NULL);
 781         if (rc)
 782                 goto out;
 783         rc = smc_llc_link_init(lnk);
 784         if (rc)
 785                 goto out;
 786         rc = smc_wr_alloc_link_mem(lnk);
 787         if (rc)
 788                 goto clear_llc_lnk;
 789         rc = smc_ib_create_protection_domain(lnk);
 790         if (rc)
 791                 goto free_link_mem;
 792         rc = smc_ib_create_queue_pair(lnk);
 793         if (rc)
 794                 goto dealloc_pd;
 795         rc = smc_wr_create_link(lnk);
 796         if (rc)
 797                 goto destroy_qp;
 798         lnk->state = SMC_LNK_ACTIVATING;
 799         return 0;
 800
 801 destroy_qp:
 802         smc_ib_destroy_queue_pair(lnk);
 803 dealloc_pd:
 804         smc_ib_dealloc_protection_domain(lnk);
 805 free_link_mem:
 806         smc_wr_free_link_mem(lnk);
 807 clear_llc_lnk:
 808         smc_llc_link_clear(lnk, false);
 809 out:
 810         smc_ibdev_cnt_dec(lnk);
 811         put_device(&lnk->smcibdev->ibdev->dev);
 812         smcibdev = lnk->smcibdev;
 813         memset(lnk, 0, sizeof(struct smc_link));
 814         lnk->state = SMC_LNK_UNUSED;
 815         if (!atomic_dec_return(&smcibdev->lnk_cnt))
 816                 wake_up(&smcibdev->lnks_deleted);
 817         smc_lgr_put(lgr); /* lgr_hold above */
 818         return rc;
 819 }
 820
 821 /* create a new SMC link group */
 822 static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
 823 {
 824         struct smc_link_group *lgr;
 825         struct list_head *lgr_list;
 826         struct smcd_dev *smcd;
 827         struct smc_link *lnk;
 828         spinlock_t *lgr_lock;
 829         u8 link_idx;
 830         int rc = 0;
 831         int i;
 832
 833         if (ini->is_smcd && ini->vlan_id) {
 834                 if (smc_ism_get_vlan(ini->ism_dev[ini->ism_selected],
 835                                      ini->vlan_id)) {
 836                         rc = SMC_CLC_DECL_ISMVLANERR;
 837                         goto out;
 838                 }
 839         }
 840
 841         lgr = kzalloc(sizeof(*lgr), GFP_KERNEL);
 842         if (!lgr) {
 843                 rc = SMC_CLC_DECL_MEM;
 844                 goto ism_put_vlan;
 845         }
 846         lgr->tx_wq = alloc_workqueue("smc_tx_wq-%*phN", 0, 0,
 847                                      SMC_LGR_ID_SIZE, &lgr->id);
 848         if (!lgr->tx_wq) {
 849                 rc = -ENOMEM;
 850                 goto free_lgr;
 851         }
 852         lgr->is_smcd = ini->is_smcd;
 853         lgr->sync_err = 0;
 854         lgr->terminating = 0;
 855         lgr->freeing = 0;
 856         lgr->vlan_id = ini->vlan_id;
 857         refcount_set(&lgr->refcnt, 1); /* set lgr refcnt to 1 */
 858         init_rwsem(&lgr->sndbufs_lock);
 859         init_rwsem(&lgr->rmbs_lock);
 860         rwlock_init(&lgr->conns_lock);
 861         for (i = 0; i < SMC_RMBE_SIZES; i++) {
 862                 INIT_LIST_HEAD(&lgr->sndbufs[i]);
 863                 INIT_LIST_HEAD(&lgr->rmbs[i]);
 864         }
 865         lgr->next_link_id = 0;
 866         smc_lgr_list.num += SMC_LGR_NUM_INCR;
 867         memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE);
 868         INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
 869         INIT_WORK(&lgr->terminate_work, smc_lgr_terminate_work);
 870         lgr->conns_all = RB_ROOT;
 871         if (ini->is_smcd) {
 872                 /* SMC-D specific settings */
 873                 smcd = ini->ism_dev[ini->ism_selected];
 874                 get_device(smcd->ops->get_dev(smcd));
 875                 lgr->peer_gid = ini->ism_peer_gid[ini->ism_selected];
 876                 lgr->smcd = ini->ism_dev[ini->ism_selected];
 877                 lgr_list = &ini->ism_dev[ini->ism_selected]->lgr_list;
 878                 lgr_lock = &lgr->smcd->lgr_lock;
 879                 lgr->smc_version = ini->smcd_version;
 880                 lgr->peer_shutdown = 0;
 881                 atomic_inc(&ini->ism_dev[ini->ism_selected]->lgr_cnt);
 882         } else {
 883                 /* SMC-R specific settings */
 884                 struct smc_ib_device *ibdev;
 885                 int ibport;
 886
 887                 lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
 888                 lgr->smc_version = ini->smcr_version;
 889                 memcpy(lgr->peer_systemid, ini->peer_systemid,
 890                        SMC_SYSTEMID_LEN);
 891                 if (lgr->smc_version == SMC_V2) {
 892                         ibdev = ini->smcrv2.ib_dev_v2;
 893                         ibport = ini->smcrv2.ib_port_v2;
 894                         lgr->saddr = ini->smcrv2.saddr;
 895                         lgr->uses_gateway = ini->smcrv2.uses_gateway;
 896                         memcpy(lgr->nexthop_mac, ini->smcrv2.nexthop_mac,
 897                                ETH_ALEN);
 898                 } else {
 899                         ibdev = ini->ib_dev;
 900                         ibport = ini->ib_port;
 901                 }
 902                 memcpy(lgr->pnet_id, ibdev->pnetid[ibport - 1],
 903                        SMC_MAX_PNETID_LEN);
 904                 rc = smc_wr_alloc_lgr_mem(lgr);
 905                 if (rc)
 906                         goto free_wq;
 907                 smc_llc_lgr_init(lgr, smc);
 908
 909                 link_idx = SMC_SINGLE_LINK;
 910                 lnk = &lgr->lnk[link_idx];
 911                 rc = smcr_link_init(lgr, lnk, link_idx, ini);
 912                 if (rc) {
 913                         smc_wr_free_lgr_mem(lgr);
 914                         goto free_wq;
 915                 }
 916                 lgr->net = smc_ib_net(lnk->smcibdev);
 917                 lgr_list = &smc_lgr_list.list;
 918                 lgr_lock = &smc_lgr_list.lock;
 919                 lgr->buf_type = lgr->net->smc.sysctl_smcr_buf_type;
 920                 atomic_inc(&lgr_cnt);
 921         }
 922         smc->conn.lgr = lgr;
 923         spin_lock_bh(lgr_lock);
 924         list_add_tail(&lgr->list, lgr_list);
 925         spin_unlock_bh(lgr_lock);
 926         return 0;
 927
 928 free_wq:
 929         destroy_workqueue(lgr->tx_wq);
 930 free_lgr:
 931         kfree(lgr);
 932 ism_put_vlan:
 933         if (ini->is_smcd && ini->vlan_id)
 934                 smc_ism_put_vlan(ini->ism_dev[ini->ism_selected], ini->vlan_id);
 935 out:
 936         if (rc < 0) {
 937                 if (rc == -ENOMEM)
 938                         rc = SMC_CLC_DECL_MEM;
 939                 else
 940                         rc = SMC_CLC_DECL_INTERR;
 941         }
 942         return rc;
 943 }
 944
 945 static int smc_write_space(struct smc_connection *conn)
 946 {
 947         int buffer_len = conn->peer_rmbe_size;
 948         union smc_host_cursor prod;
 949         union smc_host_cursor cons;
 950         int space;
 951
 952         smc_curs_copy(&prod, &conn->local_tx_ctrl.prod, conn);
 953         smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
 954         /* determine rx_buf space */
 955         space = buffer_len - smc_curs_diff(buffer_len, &cons, &prod);
 956         return space;
 957 }
 958
 959 static int smc_switch_cursor(struct smc_sock *smc, struct smc_cdc_tx_pend *pend,
 960                              struct smc_wr_buf *wr_buf)
 961 {
 962         struct smc_connection *conn = &smc->conn;
 963         union smc_host_cursor cons, fin;
 964         int rc = 0;
 965         int diff;
 966
 967         smc_curs_copy(&conn->tx_curs_sent, &conn->tx_curs_fin, conn);
 968         smc_curs_copy(&fin, &conn->local_tx_ctrl_fin, conn);
 969         /* set prod cursor to old state, enforce tx_rdma_writes() */
 970         smc_curs_copy(&conn->local_tx_ctrl.prod, &fin, conn);
 971         smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
 972
 973         if (smc_curs_comp(conn->peer_rmbe_size, &cons, &fin) < 0) {
 974                 /* cons cursor advanced more than fin, and prod was set
 975                  * fin above, so now prod is smaller than cons. Fix that.
 976                  */
 977                 diff = smc_curs_diff(conn->peer_rmbe_size, &fin, &cons);
 978                 smc_curs_add(conn->sndbuf_desc->len,
 979                              &conn->tx_curs_sent, diff);
 980                 smc_curs_add(conn->sndbuf_desc->len,
 981                              &conn->tx_curs_fin, diff);
 982
 983                 smp_mb__before_atomic();
 984                 atomic_add(diff, &conn->sndbuf_space);
 985                 smp_mb__after_atomic();
 986
 987                 smc_curs_add(conn->peer_rmbe_size,
 988                              &conn->local_tx_ctrl.prod, diff);
 989                 smc_curs_add(conn->peer_rmbe_size,
 990                              &conn->local_tx_ctrl_fin, diff);
 991         }
 992         /* recalculate, value is used by tx_rdma_writes() */
 993         atomic_set(&smc->conn.peer_rmbe_space, smc_write_space(conn));
 994
 995         if (smc->sk.sk_state != SMC_INIT &&
 996             smc->sk.sk_state != SMC_CLOSED) {
 997                 rc = smcr_cdc_msg_send_validation(conn, pend, wr_buf);
 998                 if (!rc) {
 999                         queue_delayed_work(conn->lgr->tx_wq, &conn->tx_work, 0);
1000                         smc->sk.sk_data_ready(&smc->sk);
1001                 }
1002         } else {
1003                 smc_wr_tx_put_slot(conn->lnk,
1004                                    (struct smc_wr_tx_pend_priv *)pend);
1005         }
1006         return rc;
1007 }
1008
1009 void smc_switch_link_and_count(struct smc_connection *conn,
1010                                struct smc_link *to_lnk)
1011 {
1012         atomic_dec(&conn->lnk->conn_cnt);
1013         /* link_hold in smc_conn_create() */
1014         smcr_link_put(conn->lnk);
1015         conn->lnk = to_lnk;
1016         atomic_inc(&conn->lnk->conn_cnt);
1017         /* link_put in smc_conn_free() */
1018         smcr_link_hold(conn->lnk);
1019 }
1020
1021 struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
1022                                   struct smc_link *from_lnk, bool is_dev_err)
1023 {
1024         struct smc_link *to_lnk = NULL;
1025         struct smc_cdc_tx_pend *pend;
1026         struct smc_connection *conn;
1027         struct smc_wr_buf *wr_buf;
1028         struct smc_sock *smc;
1029         struct rb_node *node;
1030         int i, rc = 0;
1031
1032         /* link is inactive, wake up tx waiters */
1033         smc_wr_wakeup_tx_wait(from_lnk);
1034
1035         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1036                 if (!smc_link_active(&lgr->lnk[i]) || i == from_lnk->link_idx)
1037                         continue;
1038                 if (is_dev_err && from_lnk->smcibdev == lgr->lnk[i].smcibdev &&
1039                     from_lnk->ibport == lgr->lnk[i].ibport) {
1040                         continue;
1041                 }
1042                 to_lnk = &lgr->lnk[i];
1043                 break;
1044         }
1045         if (!to_lnk || !smc_wr_tx_link_hold(to_lnk)) {
1046                 smc_lgr_terminate_sched(lgr);
1047                 return NULL;
1048         }
1049 again:
1050         read_lock_bh(&lgr->conns_lock);
1051         for (node = rb_first(&lgr->conns_all); node; node = rb_next(node)) {
1052                 conn = rb_entry(node, struct smc_connection, alert_node);
1053                 if (conn->lnk != from_lnk)
1054                         continue;
1055                 smc = container_of(conn, struct smc_sock, conn);
1056                 /* conn->lnk not yet set in SMC_INIT state */
1057                 if (smc->sk.sk_state == SMC_INIT)
1058                         continue;
1059                 if (smc->sk.sk_state == SMC_CLOSED ||
1060                     smc->sk.sk_state == SMC_PEERCLOSEWAIT1 ||
1061                     smc->sk.sk_state == SMC_PEERCLOSEWAIT2 ||
1062                     smc->sk.sk_state == SMC_APPFINCLOSEWAIT ||
1063                     smc->sk.sk_state == SMC_APPCLOSEWAIT1 ||
1064                     smc->sk.sk_state == SMC_APPCLOSEWAIT2 ||
1065                     smc->sk.sk_state == SMC_PEERFINCLOSEWAIT ||
1066                     smc->sk.sk_state == SMC_PEERABORTWAIT ||
1067                     smc->sk.sk_state == SMC_PROCESSABORT) {
1068                         spin_lock_bh(&conn->send_lock);
1069                         smc_switch_link_and_count(conn, to_lnk);
1070                         spin_unlock_bh(&conn->send_lock);
1071                         continue;
1072                 }
1073                 sock_hold(&smc->sk);
1074                 read_unlock_bh(&lgr->conns_lock);
1075                 /* pre-fetch buffer outside of send_lock, might sleep */
1076                 rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend);
1077                 if (rc)
1078                         goto err_out;
1079                 /* avoid race with smcr_tx_sndbuf_nonempty() */
1080                 spin_lock_bh(&conn->send_lock);
1081                 smc_switch_link_and_count(conn, to_lnk);
1082                 rc = smc_switch_cursor(smc, pend, wr_buf);
1083                 spin_unlock_bh(&conn->send_lock);
1084                 sock_put(&smc->sk);
1085                 if (rc)
1086                         goto err_out;
1087                 goto again;
1088         }
1089         read_unlock_bh(&lgr->conns_lock);
1090         smc_wr_tx_link_put(to_lnk);
1091         return to_lnk;
1092
1093 err_out:
1094         smcr_link_down_cond_sched(to_lnk);
1095         smc_wr_tx_link_put(to_lnk);
1096         return NULL;
1097 }
1098
1099 static void smcr_buf_unuse(struct smc_buf_desc *buf_desc, bool is_rmb,
1100                            struct smc_link_group *lgr)
1101 {
1102         struct rw_semaphore *lock;      /* lock buffer list */
1103         int rc;
1104
1105         if (is_rmb && buf_desc->is_conf_rkey && !list_empty(&lgr->list)) {
1106                 /* unregister rmb with peer */
1107                 rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
1108                 if (!rc) {
1109                         /* protect against smc_llc_cli_rkey_exchange() */
1110                         down_read(&lgr->llc_conf_mutex);
1111                         smc_llc_do_delete_rkey(lgr, buf_desc);
1112                         buf_desc->is_conf_rkey = false;
1113                         up_read(&lgr->llc_conf_mutex);
1114                         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
1115                 }
1116         }
1117
1118         if (buf_desc->is_reg_err) {
1119                 /* buf registration failed, reuse not possible */
1120                 lock = is_rmb ? &lgr->rmbs_lock :
1121                                 &lgr->sndbufs_lock;
1122                 down_write(lock);
1123                 list_del(&buf_desc->list);
1124                 up_write(lock);
1125
1126                 smc_buf_free(lgr, is_rmb, buf_desc);
1127         } else {
1128                 /* memzero_explicit provides potential memory barrier semantics */
1129                 memzero_explicit(buf_desc->cpu_addr, buf_desc->len);
1130                 WRITE_ONCE(buf_desc->used, 0);
1131         }
1132 }
1133
1134 static void smc_buf_unuse(struct smc_connection *conn,
1135                           struct smc_link_group *lgr)
1136 {
1137         if (conn->sndbuf_desc) {
1138                 if (!lgr->is_smcd && conn->sndbuf_desc->is_vm) {
1139                         smcr_buf_unuse(conn->sndbuf_desc, false, lgr);
1140                 } else {
1141                         memzero_explicit(conn->sndbuf_desc->cpu_addr, conn->sndbuf_desc->len);
1142                         WRITE_ONCE(conn->sndbuf_desc->used, 0);
1143                 }
1144         }
1145         if (conn->rmb_desc) {
1146                 if (!lgr->is_smcd) {
1147                         smcr_buf_unuse(conn->rmb_desc, true, lgr);
1148                 } else {
1149                         memzero_explicit(conn->rmb_desc->cpu_addr,
1150                                          conn->rmb_desc->len + sizeof(struct smcd_cdc_msg));
1151                         WRITE_ONCE(conn->rmb_desc->used, 0);
1152                 }
1153         }
1154 }
1155
1156 /* remove a finished connection from its link group */
1157 void smc_conn_free(struct smc_connection *conn)
1158 {
1159         struct smc_link_group *lgr = conn->lgr;
1160
1161         if (!lgr || conn->freed)
1162                 /* Connection has never been registered in a
1163                  * link group, or has already been freed.
1164                  */
1165                 return;
1166
1167         conn->freed = 1;
1168         if (!smc_conn_lgr_valid(conn))
1169                 /* Connection has already unregistered from
1170                  * link group.
1171                  */
1172                 goto lgr_put;
1173
1174         if (lgr->is_smcd) {
1175                 if (!list_empty(&lgr->list))
1176                         smc_ism_unset_conn(conn);
1177                 tasklet_kill(&conn->rx_tsklet);
1178         } else {
1179                 smc_cdc_wait_pend_tx_wr(conn);
1180                 if (current_work() != &conn->abort_work)
1181                         cancel_work_sync(&conn->abort_work);
1182         }
1183         if (!list_empty(&lgr->list)) {
1184                 smc_buf_unuse(conn, lgr); /* allow buffer reuse */
1185                 smc_lgr_unregister_conn(conn);
1186         }
1187
1188         if (!lgr->conns_num)
1189                 smc_lgr_schedule_free_work(lgr);
1190 lgr_put:
1191         if (!lgr->is_smcd)
1192                 smcr_link_put(conn->lnk); /* link_hold in smc_conn_create() */
1193         smc_lgr_put(lgr); /* lgr_hold in smc_conn_create() */
1194 }
1195
1196 /* unregister a link from a buf_desc */
1197 static void smcr_buf_unmap_link(struct smc_buf_desc *buf_desc, bool is_rmb,
1198                                 struct smc_link *lnk)
1199 {
1200         if (is_rmb || buf_desc->is_vm)
1201                 buf_desc->is_reg_mr[lnk->link_idx] = false;
1202         if (!buf_desc->is_map_ib[lnk->link_idx])
1203                 return;
1204
1205         if ((is_rmb || buf_desc->is_vm) &&
1206             buf_desc->mr[lnk->link_idx]) {
1207                 smc_ib_put_memory_region(buf_desc->mr[lnk->link_idx]);
1208                 buf_desc->mr[lnk->link_idx] = NULL;
1209         }
1210         if (is_rmb)
1211                 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_FROM_DEVICE);
1212         else
1213                 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_TO_DEVICE);
1214
1215         sg_free_table(&buf_desc->sgt[lnk->link_idx]);
1216         buf_desc->is_map_ib[lnk->link_idx] = false;
1217 }
1218
1219 /* unmap all buffers of lgr for a deleted link */
1220 static void smcr_buf_unmap_lgr(struct smc_link *lnk)
1221 {
1222         struct smc_link_group *lgr = lnk->lgr;
1223         struct smc_buf_desc *buf_desc, *bf;
1224         int i;
1225
1226         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1227                 down_write(&lgr->rmbs_lock);
1228                 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list)
1229                         smcr_buf_unmap_link(buf_desc, true, lnk);
1230                 up_write(&lgr->rmbs_lock);
1231
1232                 down_write(&lgr->sndbufs_lock);
1233                 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i],
1234                                          list)
1235                         smcr_buf_unmap_link(buf_desc, false, lnk);
1236                 up_write(&lgr->sndbufs_lock);
1237         }
1238 }
1239
1240 static void smcr_rtoken_clear_link(struct smc_link *lnk)
1241 {
1242         struct smc_link_group *lgr = lnk->lgr;
1243         int i;
1244
1245         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1246                 lgr->rtokens[i][lnk->link_idx].rkey = 0;
1247                 lgr->rtokens[i][lnk->link_idx].dma_addr = 0;
1248         }
1249 }
1250
1251 static void __smcr_link_clear(struct smc_link *lnk)
1252 {
1253         struct smc_link_group *lgr = lnk->lgr;
1254         struct smc_ib_device *smcibdev;
1255
1256         smc_wr_free_link_mem(lnk);
1257         smc_ibdev_cnt_dec(lnk);
1258         put_device(&lnk->smcibdev->ibdev->dev);
1259         smcibdev = lnk->smcibdev;
1260         memset(lnk, 0, sizeof(struct smc_link));
1261         lnk->state = SMC_LNK_UNUSED;
1262         if (!atomic_dec_return(&smcibdev->lnk_cnt))
1263                 wake_up(&smcibdev->lnks_deleted);
1264         smc_lgr_put(lgr); /* lgr_hold in smcr_link_init() */
1265 }
1266
1267 /* must be called under lgr->llc_conf_mutex lock */
1268 void smcr_link_clear(struct smc_link *lnk, bool log)
1269 {
1270         if (!lnk->lgr || lnk->clearing ||
1271             lnk->state == SMC_LNK_UNUSED)
1272                 return;
1273         lnk->clearing = 1;
1274         lnk->peer_qpn = 0;
1275         smc_llc_link_clear(lnk, log);
1276         smcr_buf_unmap_lgr(lnk);
1277         smcr_rtoken_clear_link(lnk);
1278         smc_ib_modify_qp_error(lnk);
1279         smc_wr_free_link(lnk);
1280         smc_ib_destroy_queue_pair(lnk);
1281         smc_ib_dealloc_protection_domain(lnk);
1282         smcr_link_put(lnk); /* theoretically last link_put */
1283 }
1284
1285 void smcr_link_hold(struct smc_link *lnk)
1286 {
1287         refcount_inc(&lnk->refcnt);
1288 }
1289
1290 void smcr_link_put(struct smc_link *lnk)
1291 {
1292         if (refcount_dec_and_test(&lnk->refcnt))
1293                 __smcr_link_clear(lnk);
1294 }
1295
1296 static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb,
1297                           struct smc_buf_desc *buf_desc)
1298 {
1299         int i;
1300
1301         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1302                 smcr_buf_unmap_link(buf_desc, is_rmb, &lgr->lnk[i]);
1303
1304         if (!buf_desc->is_vm && buf_desc->pages)
1305                 __free_pages(buf_desc->pages, buf_desc->order);
1306         else if (buf_desc->is_vm && buf_desc->cpu_addr)
1307                 vfree(buf_desc->cpu_addr);
1308         kfree(buf_desc);
1309 }
1310
1311 static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb,
1312                           struct smc_buf_desc *buf_desc)
1313 {
1314         if (is_dmb) {
1315                 /* restore original buf len */
1316                 buf_desc->len += sizeof(struct smcd_cdc_msg);
1317                 smc_ism_unregister_dmb(lgr->smcd, buf_desc);
1318         } else {
1319                 kfree(buf_desc->cpu_addr);
1320         }
1321         kfree(buf_desc);
1322 }
1323
1324 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
1325                          struct smc_buf_desc *buf_desc)
1326 {
1327         if (lgr->is_smcd)
1328                 smcd_buf_free(lgr, is_rmb, buf_desc);
1329         else
1330                 smcr_buf_free(lgr, is_rmb, buf_desc);
1331 }
1332
1333 static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb)
1334 {
1335         struct smc_buf_desc *buf_desc, *bf_desc;
1336         struct list_head *buf_list;
1337         int i;
1338
1339         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1340                 if (is_rmb)
1341                         buf_list = &lgr->rmbs[i];
1342                 else
1343                         buf_list = &lgr->sndbufs[i];
1344                 list_for_each_entry_safe(buf_desc, bf_desc, buf_list,
1345                                          list) {
1346                         list_del(&buf_desc->list);
1347                         smc_buf_free(lgr, is_rmb, buf_desc);
1348                 }
1349         }
1350 }
1351
1352 static void smc_lgr_free_bufs(struct smc_link_group *lgr)
1353 {
1354         /* free send buffers */
1355         __smc_lgr_free_bufs(lgr, false);
1356         /* free rmbs */
1357         __smc_lgr_free_bufs(lgr, true);
1358 }
1359
1360 /* won't be freed until no one accesses to lgr anymore */
1361 static void __smc_lgr_free(struct smc_link_group *lgr)
1362 {
1363         smc_lgr_free_bufs(lgr);
1364         if (lgr->is_smcd) {
1365                 if (!atomic_dec_return(&lgr->smcd->lgr_cnt))
1366                         wake_up(&lgr->smcd->lgrs_deleted);
1367         } else {
1368                 smc_wr_free_lgr_mem(lgr);
1369                 if (!atomic_dec_return(&lgr_cnt))
1370                         wake_up(&lgrs_deleted);
1371         }
1372         kfree(lgr);
1373 }
1374
1375 /* remove a link group */
1376 static void smc_lgr_free(struct smc_link_group *lgr)
1377 {
1378         int i;
1379
1380         if (!lgr->is_smcd) {
1381                 down_write(&lgr->llc_conf_mutex);
1382                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1383                         if (lgr->lnk[i].state != SMC_LNK_UNUSED)
1384                                 smcr_link_clear(&lgr->lnk[i], false);
1385                 }
1386                 up_write(&lgr->llc_conf_mutex);
1387                 smc_llc_lgr_clear(lgr);
1388         }
1389
1390         destroy_workqueue(lgr->tx_wq);
1391         if (lgr->is_smcd) {
1392                 smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
1393                 put_device(lgr->smcd->ops->get_dev(lgr->smcd));
1394         }
1395         smc_lgr_put(lgr); /* theoretically last lgr_put */
1396 }
1397
1398 void smc_lgr_hold(struct smc_link_group *lgr)
1399 {
1400         refcount_inc(&lgr->refcnt);
1401 }
1402
1403 void smc_lgr_put(struct smc_link_group *lgr)
1404 {
1405         if (refcount_dec_and_test(&lgr->refcnt))
1406                 __smc_lgr_free(lgr);
1407 }
1408
1409 static void smc_sk_wake_ups(struct smc_sock *smc)
1410 {
1411         smc->sk.sk_write_space(&smc->sk);
1412         smc->sk.sk_data_ready(&smc->sk);
1413         smc->sk.sk_state_change(&smc->sk);
1414 }
1415
1416 /* kill a connection */
1417 static void smc_conn_kill(struct smc_connection *conn, bool soft)
1418 {
1419         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1420
1421         if (conn->lgr->is_smcd && conn->lgr->peer_shutdown)
1422                 conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
1423         else
1424                 smc_close_abort(conn);
1425         conn->killed = 1;
1426         smc->sk.sk_err = ECONNABORTED;
1427         smc_sk_wake_ups(smc);
1428         if (conn->lgr->is_smcd) {
1429                 smc_ism_unset_conn(conn);
1430                 if (soft)
1431                         tasklet_kill(&conn->rx_tsklet);
1432                 else
1433                         tasklet_unlock_wait(&conn->rx_tsklet);
1434         } else {
1435                 smc_cdc_wait_pend_tx_wr(conn);
1436         }
1437         smc_lgr_unregister_conn(conn);
1438         smc_close_active_abort(smc);
1439 }
1440
1441 static void smc_lgr_cleanup(struct smc_link_group *lgr)
1442 {
1443         if (lgr->is_smcd) {
1444                 smc_ism_signal_shutdown(lgr);
1445         } else {
1446                 u32 rsn = lgr->llc_termination_rsn;
1447
1448                 if (!rsn)
1449                         rsn = SMC_LLC_DEL_PROG_INIT_TERM;
1450                 smc_llc_send_link_delete_all(lgr, false, rsn);
1451                 smcr_lgr_link_deactivate_all(lgr);
1452         }
1453 }
1454
1455 /* terminate link group
1456  * @soft: true if link group shutdown can take its time
1457  *        false if immediate link group shutdown is required
1458  */
1459 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft)
1460 {
1461         struct smc_connection *conn;
1462         struct smc_sock *smc;
1463         struct rb_node *node;
1464
1465         if (lgr->terminating)
1466                 return; /* lgr already terminating */
1467         /* cancel free_work sync, will terminate when lgr->freeing is set */
1468         cancel_delayed_work(&lgr->free_work);
1469         lgr->terminating = 1;
1470
1471         /* kill remaining link group connections */
1472         read_lock_bh(&lgr->conns_lock);
1473         node = rb_first(&lgr->conns_all);
1474         while (node) {
1475                 read_unlock_bh(&lgr->conns_lock);
1476                 conn = rb_entry(node, struct smc_connection, alert_node);
1477                 smc = container_of(conn, struct smc_sock, conn);
1478                 sock_hold(&smc->sk); /* sock_put below */
1479                 lock_sock(&smc->sk);
1480                 smc_conn_kill(conn, soft);
1481                 release_sock(&smc->sk);
1482                 sock_put(&smc->sk); /* sock_hold above */
1483                 read_lock_bh(&lgr->conns_lock);
1484                 node = rb_first(&lgr->conns_all);
1485         }
1486         read_unlock_bh(&lgr->conns_lock);
1487         smc_lgr_cleanup(lgr);
1488         smc_lgr_free(lgr);
1489 }
1490
1491 /* unlink link group and schedule termination */
1492 void smc_lgr_terminate_sched(struct smc_link_group *lgr)
1493 {
1494         spinlock_t *lgr_lock;
1495
1496         smc_lgr_list_head(lgr, &lgr_lock);
1497         spin_lock_bh(lgr_lock);
1498         if (list_empty(&lgr->list) || lgr->terminating || lgr->freeing) {
1499                 spin_unlock_bh(lgr_lock);
1500                 return; /* lgr already terminating */
1501         }
1502         list_del_init(&lgr->list);
1503         lgr->freeing = 1;
1504         spin_unlock_bh(lgr_lock);
1505         schedule_work(&lgr->terminate_work);
1506 }
1507
1508 /* Called when peer lgr shutdown (regularly or abnormally) is received */
1509 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
1510 {
1511         struct smc_link_group *lgr, *l;
1512         LIST_HEAD(lgr_free_list);
1513
1514         /* run common cleanup function and build free list */
1515         spin_lock_bh(&dev->lgr_lock);
1516         list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) {
1517                 if ((!peer_gid || lgr->peer_gid == peer_gid) &&
1518                     (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
1519                         if (peer_gid) /* peer triggered termination */
1520                                 lgr->peer_shutdown = 1;
1521                         list_move(&lgr->list, &lgr_free_list);
1522                         lgr->freeing = 1;
1523                 }
1524         }
1525         spin_unlock_bh(&dev->lgr_lock);
1526
1527         /* cancel the regular free workers and actually free lgrs */
1528         list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
1529                 list_del_init(&lgr->list);
1530                 schedule_work(&lgr->terminate_work);
1531         }
1532 }
1533
1534 /* Called when an SMCD device is removed or the smc module is unloaded */
1535 void smc_smcd_terminate_all(struct smcd_dev *smcd)
1536 {
1537         struct smc_link_group *lgr, *lg;
1538         LIST_HEAD(lgr_free_list);
1539
1540         spin_lock_bh(&smcd->lgr_lock);
1541         list_splice_init(&smcd->lgr_list, &lgr_free_list);
1542         list_for_each_entry(lgr, &lgr_free_list, list)
1543                 lgr->freeing = 1;
1544         spin_unlock_bh(&smcd->lgr_lock);
1545
1546         list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1547                 list_del_init(&lgr->list);
1548                 __smc_lgr_terminate(lgr, false);
1549         }
1550
1551         if (atomic_read(&smcd->lgr_cnt))
1552                 wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt));
1553 }
1554
1555 /* Called when an SMCR device is removed or the smc module is unloaded.
1556  * If smcibdev is given, all SMCR link groups using this device are terminated.
1557  * If smcibdev is NULL, all SMCR link groups are terminated.
1558  */
1559 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
1560 {
1561         struct smc_link_group *lgr, *lg;
1562         LIST_HEAD(lgr_free_list);
1563         int i;
1564
1565         spin_lock_bh(&smc_lgr_list.lock);
1566         if (!smcibdev) {
1567                 list_splice_init(&smc_lgr_list.list, &lgr_free_list);
1568                 list_for_each_entry(lgr, &lgr_free_list, list)
1569                         lgr->freeing = 1;
1570         } else {
1571                 list_for_each_entry_safe(lgr, lg, &smc_lgr_list.list, list) {
1572                         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1573                                 if (lgr->lnk[i].smcibdev == smcibdev)
1574                                         smcr_link_down_cond_sched(&lgr->lnk[i]);
1575                         }
1576                 }
1577         }
1578         spin_unlock_bh(&smc_lgr_list.lock);
1579
1580         list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1581                 list_del_init(&lgr->list);
1582                 smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_OP_INIT_TERM);
1583                 __smc_lgr_terminate(lgr, false);
1584         }
1585
1586         if (smcibdev) {
1587                 if (atomic_read(&smcibdev->lnk_cnt))
1588                         wait_event(smcibdev->lnks_deleted,
1589                                    !atomic_read(&smcibdev->lnk_cnt));
1590         } else {
1591                 if (atomic_read(&lgr_cnt))
1592                         wait_event(lgrs_deleted, !atomic_read(&lgr_cnt));
1593         }
1594 }
1595
1596 /* set new lgr type and clear all asymmetric link tagging */
1597 void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type)
1598 {
1599         char *lgr_type = "";
1600         int i;
1601
1602         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1603                 if (smc_link_usable(&lgr->lnk[i]))
1604                         lgr->lnk[i].link_is_asym = false;
1605         if (lgr->type == new_type)
1606                 return;
1607         lgr->type = new_type;
1608
1609         switch (lgr->type) {
1610         case SMC_LGR_NONE:
1611                 lgr_type = "NONE";
1612                 break;
1613         case SMC_LGR_SINGLE:
1614                 lgr_type = "SINGLE";
1615                 break;
1616         case SMC_LGR_SYMMETRIC:
1617                 lgr_type = "SYMMETRIC";
1618                 break;
1619         case SMC_LGR_ASYMMETRIC_PEER:
1620                 lgr_type = "ASYMMETRIC_PEER";
1621                 break;
1622         case SMC_LGR_ASYMMETRIC_LOCAL:
1623                 lgr_type = "ASYMMETRIC_LOCAL";
1624                 break;
1625         }
1626         pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu state changed: "
1627                             "%s, pnetid %.16s\n", SMC_LGR_ID_SIZE, &lgr->id,
1628                             lgr->net->net_cookie, lgr_type, lgr->pnet_id);
1629 }
1630
1631 /* set new lgr type and tag a link as asymmetric */
1632 void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
1633                             enum smc_lgr_type new_type, int asym_lnk_idx)
1634 {
1635         smcr_lgr_set_type(lgr, new_type);
1636         lgr->lnk[asym_lnk_idx].link_is_asym = true;
1637 }
1638
1639 /* abort connection, abort_work scheduled from tasklet context */
1640 static void smc_conn_abort_work(struct work_struct *work)
1641 {
1642         struct smc_connection *conn = container_of(work,
1643                                                    struct smc_connection,
1644                                                    abort_work);
1645         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1646
1647         lock_sock(&smc->sk);
1648         smc_conn_kill(conn, true);
1649         release_sock(&smc->sk);
1650         sock_put(&smc->sk); /* sock_hold done by schedulers of abort_work */
1651 }
1652
1653 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport)
1654 {
1655         struct smc_link_group *lgr, *n;
1656
1657         spin_lock_bh(&smc_lgr_list.lock);
1658         list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1659                 struct smc_link *link;
1660
1661                 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1662                             SMC_MAX_PNETID_LEN) ||
1663                     lgr->type == SMC_LGR_SYMMETRIC ||
1664                     lgr->type == SMC_LGR_ASYMMETRIC_PEER ||
1665                     !rdma_dev_access_netns(smcibdev->ibdev, lgr->net))
1666                         continue;
1667
1668                 /* trigger local add link processing */
1669                 link = smc_llc_usable_link(lgr);
1670                 if (link)
1671                         smc_llc_add_link_local(link);
1672         }
1673         spin_unlock_bh(&smc_lgr_list.lock);
1674 }
1675
1676 /* link is down - switch connections to alternate link,
1677  * must be called under lgr->llc_conf_mutex lock
1678  */
1679 static void smcr_link_down(struct smc_link *lnk)
1680 {
1681         struct smc_link_group *lgr = lnk->lgr;
1682         struct smc_link *to_lnk;
1683         int del_link_id;
1684
1685         if (!lgr || lnk->state == SMC_LNK_UNUSED || list_empty(&lgr->list))
1686                 return;
1687
1688         to_lnk = smc_switch_conns(lgr, lnk, true);
1689         if (!to_lnk) { /* no backup link available */
1690                 smcr_link_clear(lnk, true);
1691                 return;
1692         }
1693         smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
1694         del_link_id = lnk->link_id;
1695
1696         if (lgr->role == SMC_SERV) {
1697                 /* trigger local delete link processing */
1698                 smc_llc_srv_delete_link_local(to_lnk, del_link_id);
1699         } else {
1700                 if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
1701                         /* another llc task is ongoing */
1702                         up_write(&lgr->llc_conf_mutex);
1703                         wait_event_timeout(lgr->llc_flow_waiter,
1704                                 (list_empty(&lgr->list) ||
1705                                  lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE),
1706                                 SMC_LLC_WAIT_TIME);
1707                         down_write(&lgr->llc_conf_mutex);
1708                 }
1709                 if (!list_empty(&lgr->list)) {
1710                         smc_llc_send_delete_link(to_lnk, del_link_id,
1711                                                  SMC_LLC_REQ, true,
1712                                                  SMC_LLC_DEL_LOST_PATH);
1713                         smcr_link_clear(lnk, true);
1714                 }
1715                 wake_up(&lgr->llc_flow_waiter); /* wake up next waiter */
1716         }
1717 }
1718
1719 /* must be called under lgr->llc_conf_mutex lock */
1720 void smcr_link_down_cond(struct smc_link *lnk)
1721 {
1722         if (smc_link_downing(&lnk->state)) {
1723                 trace_smcr_link_down(lnk, __builtin_return_address(0));
1724                 smcr_link_down(lnk);
1725         }
1726 }
1727
1728 /* will get the lgr->llc_conf_mutex lock */
1729 void smcr_link_down_cond_sched(struct smc_link *lnk)
1730 {
1731         if (smc_link_downing(&lnk->state)) {
1732                 trace_smcr_link_down(lnk, __builtin_return_address(0));
1733                 schedule_work(&lnk->link_down_wrk);
1734         }
1735 }
1736
1737 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport)
1738 {
1739         struct smc_link_group *lgr, *n;
1740         int i;
1741
1742         list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1743                 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1744                             SMC_MAX_PNETID_LEN))
1745                         continue; /* lgr is not affected */
1746                 if (list_empty(&lgr->list))
1747                         continue;
1748                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1749                         struct smc_link *lnk = &lgr->lnk[i];
1750
1751                         if (smc_link_usable(lnk) &&
1752                             lnk->smcibdev == smcibdev && lnk->ibport == ibport)
1753                                 smcr_link_down_cond_sched(lnk);
1754                 }
1755         }
1756 }
1757
1758 static void smc_link_down_work(struct work_struct *work)
1759 {
1760         struct smc_link *link = container_of(work, struct smc_link,
1761                                              link_down_wrk);
1762         struct smc_link_group *lgr = link->lgr;
1763
1764         if (list_empty(&lgr->list))
1765                 return;
1766         wake_up_all(&lgr->llc_msg_waiter);
1767         down_write(&lgr->llc_conf_mutex);
1768         smcr_link_down(link);
1769         up_write(&lgr->llc_conf_mutex);
1770 }
1771
1772 static int smc_vlan_by_tcpsk_walk(struct net_device *lower_dev,
1773                                   struct netdev_nested_priv *priv)
1774 {
1775         unsigned short *vlan_id = (unsigned short *)priv->data;
1776
1777         if (is_vlan_dev(lower_dev)) {
1778                 *vlan_id = vlan_dev_vlan_id(lower_dev);
1779                 return 1;
1780         }
1781
1782         return 0;
1783 }
1784
1785 /* Determine vlan of internal TCP socket. */
1786 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
1787 {
1788         struct dst_entry *dst = sk_dst_get(clcsock->sk);
1789         struct netdev_nested_priv priv;
1790         struct net_device *ndev;
1791         int rc = 0;
1792
1793         ini->vlan_id = 0;
1794         if (!dst) {
1795                 rc = -ENOTCONN;
1796                 goto out;
1797         }
1798         if (!dst->dev) {
1799                 rc = -ENODEV;
1800                 goto out_rel;
1801         }
1802
1803         ndev = dst->dev;
1804         if (is_vlan_dev(ndev)) {
1805                 ini->vlan_id = vlan_dev_vlan_id(ndev);
1806                 goto out_rel;
1807         }
1808
1809         priv.data = (void *)&ini->vlan_id;
1810         rtnl_lock();
1811         netdev_walk_all_lower_dev(ndev, smc_vlan_by_tcpsk_walk, &priv);
1812         rtnl_unlock();
1813
1814 out_rel:
1815         dst_release(dst);
1816 out:
1817         return rc;
1818 }
1819
1820 static bool smcr_lgr_match(struct smc_link_group *lgr, u8 smcr_version,
1821                            u8 peer_systemid[],
1822                            u8 peer_gid[],
1823                            u8 peer_mac_v1[],
1824                            enum smc_lgr_role role, u32 clcqpn,
1825                            struct net *net)
1826 {
1827         struct smc_link *lnk;
1828         int i;
1829
1830         if (memcmp(lgr->peer_systemid, peer_systemid, SMC_SYSTEMID_LEN) ||
1831             lgr->role != role)
1832                 return false;
1833
1834         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1835                 lnk = &lgr->lnk[i];
1836
1837                 if (!smc_link_active(lnk))
1838                         continue;
1839                 /* use verbs API to check netns, instead of lgr->net */
1840                 if (!rdma_dev_access_netns(lnk->smcibdev->ibdev, net))
1841                         return false;
1842                 if ((lgr->role == SMC_SERV || lnk->peer_qpn == clcqpn) &&
1843                     !memcmp(lnk->peer_gid, peer_gid, SMC_GID_SIZE) &&
1844                     (smcr_version == SMC_V2 ||
1845                      !memcmp(lnk->peer_mac, peer_mac_v1, ETH_ALEN)))
1846                         return true;
1847         }
1848         return false;
1849 }
1850
1851 static bool smcd_lgr_match(struct smc_link_group *lgr,
1852                            struct smcd_dev *smcismdev, u64 peer_gid)
1853 {
1854         return lgr->peer_gid == peer_gid && lgr->smcd == smcismdev;
1855 }
1856
1857 /* create a new SMC connection (and a new link group if necessary) */
1858 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
1859 {
1860         struct smc_connection *conn = &smc->conn;
1861         struct net *net = sock_net(&smc->sk);
1862         struct list_head *lgr_list;
1863         struct smc_link_group *lgr;
1864         enum smc_lgr_role role;
1865         spinlock_t *lgr_lock;
1866         int rc = 0;
1867
1868         lgr_list = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_list :
1869                                   &smc_lgr_list.list;
1870         lgr_lock = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_lock :
1871                                   &smc_lgr_list.lock;
1872         ini->first_contact_local = 1;
1873         role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
1874         if (role == SMC_CLNT && ini->first_contact_peer)
1875                 /* create new link group as well */
1876                 goto create;
1877
1878         /* determine if an existing link group can be reused */
1879         spin_lock_bh(lgr_lock);
1880         list_for_each_entry(lgr, lgr_list, list) {
1881                 write_lock_bh(&lgr->conns_lock);
1882                 if ((ini->is_smcd ?
1883                      smcd_lgr_match(lgr, ini->ism_dev[ini->ism_selected],
1884                                     ini->ism_peer_gid[ini->ism_selected]) :
1885                      smcr_lgr_match(lgr, ini->smcr_version,
1886                                     ini->peer_systemid,
1887                                     ini->peer_gid, ini->peer_mac, role,
1888                                     ini->ib_clcqpn, net)) &&
1889                     !lgr->sync_err &&
1890                     (ini->smcd_version == SMC_V2 ||
1891                      lgr->vlan_id == ini->vlan_id) &&
1892                     (role == SMC_CLNT || ini->is_smcd ||
1893                     (lgr->conns_num < SMC_RMBS_PER_LGR_MAX &&
1894                       !bitmap_full(lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX)))) {
1895                         /* link group found */
1896                         ini->first_contact_local = 0;
1897                         conn->lgr = lgr;
1898                         rc = smc_lgr_register_conn(conn, false);
1899                         write_unlock_bh(&lgr->conns_lock);
1900                         if (!rc && delayed_work_pending(&lgr->free_work))
1901                                 cancel_delayed_work(&lgr->free_work);
1902                         break;
1903                 }
1904                 write_unlock_bh(&lgr->conns_lock);
1905         }
1906         spin_unlock_bh(lgr_lock);
1907         if (rc)
1908                 return rc;
1909
1910         if (role == SMC_CLNT && !ini->first_contact_peer &&
1911             ini->first_contact_local) {
1912                 /* Server reuses a link group, but Client wants to start
1913                  * a new one
1914                  * send out_of_sync decline, reason synchr. error
1915                  */
1916                 return SMC_CLC_DECL_SYNCERR;
1917         }
1918
1919 create:
1920         if (ini->first_contact_local) {
1921                 rc = smc_lgr_create(smc, ini);
1922                 if (rc)
1923                         goto out;
1924                 lgr = conn->lgr;
1925                 write_lock_bh(&lgr->conns_lock);
1926                 rc = smc_lgr_register_conn(conn, true);
1927                 write_unlock_bh(&lgr->conns_lock);
1928                 if (rc) {
1929                         smc_lgr_cleanup_early(lgr);
1930                         goto out;
1931                 }
1932         }
1933         smc_lgr_hold(conn->lgr); /* lgr_put in smc_conn_free() */
1934         if (!conn->lgr->is_smcd)
1935                 smcr_link_hold(conn->lnk); /* link_put in smc_conn_free() */
1936         conn->freed = 0;
1937         conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
1938         conn->local_tx_ctrl.len = SMC_WR_TX_SIZE;
1939         conn->urg_state = SMC_URG_READ;
1940         init_waitqueue_head(&conn->cdc_pend_tx_wq);
1941         INIT_WORK(&smc->conn.abort_work, smc_conn_abort_work);
1942         if (ini->is_smcd) {
1943                 conn->rx_off = sizeof(struct smcd_cdc_msg);
1944                 smcd_cdc_rx_init(conn); /* init tasklet for this conn */
1945         } else {
1946                 conn->rx_off = 0;
1947         }
1948 #ifndef KERNEL_HAS_ATOMIC64
1949         spin_lock_init(&conn->acurs_lock);
1950 #endif
1951
1952 out:
1953         return rc;
1954 }
1955
1956 #define SMCD_DMBE_SIZES         6 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */
1957 #define SMCR_RMBE_SIZES         5 /* 0 -> 16KB, 1 -> 32KB, .. 5 -> 512KB */
1958
1959 /* convert the RMB size into the compressed notation (minimum 16K, see
1960  * SMCD/R_DMBE_SIZES.
1961  * In contrast to plain ilog2, this rounds towards the next power of 2,
1962  * so the socket application gets at least its desired sndbuf / rcvbuf size.
1963  */
1964 static u8 smc_compress_bufsize(int size, bool is_smcd, bool is_rmb)
1965 {
1966         const unsigned int max_scat = SG_MAX_SINGLE_ALLOC * PAGE_SIZE;
1967         u8 compressed;
1968
1969         if (size <= SMC_BUF_MIN_SIZE)
1970                 return 0;
1971
1972         size = (size - 1) >> 14;  /* convert to 16K multiple */
1973         compressed = min_t(u8, ilog2(size) + 1,
1974                            is_smcd ? SMCD_DMBE_SIZES : SMCR_RMBE_SIZES);
1975
1976         if (!is_smcd && is_rmb)
1977                 /* RMBs are backed by & limited to max size of scatterlists */
1978                 compressed = min_t(u8, compressed, ilog2(max_scat >> 14));
1979
1980         return compressed;
1981 }
1982
1983 /* convert the RMB size from compressed notation into integer */
1984 int smc_uncompress_bufsize(u8 compressed)
1985 {
1986         u32 size;
1987
1988         size = 0x00000001 << (((int)compressed) + 14);
1989         return (int)size;
1990 }
1991
1992 /* try to reuse a sndbuf or rmb description slot for a certain
1993  * buffer size; if not available, return NULL
1994  */
1995 static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize,
1996                                              struct rw_semaphore *lock,
1997                                              struct list_head *buf_list)
1998 {
1999         struct smc_buf_desc *buf_slot;
2000
2001         down_read(lock);
2002         list_for_each_entry(buf_slot, buf_list, list) {
2003                 if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
2004                         up_read(lock);
2005                         return buf_slot;
2006                 }
2007         }
2008         up_read(lock);
2009         return NULL;
2010 }
2011
2012 /* one of the conditions for announcing a receiver's current window size is
2013  * that it "results in a minimum increase in the window size of 10% of the
2014  * receive buffer space" [RFC7609]
2015  */
2016 static inline int smc_rmb_wnd_update_limit(int rmbe_size)
2017 {
2018         return max_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
2019 }
2020
2021 /* map an buf to a link */
2022 static int smcr_buf_map_link(struct smc_buf_desc *buf_desc, bool is_rmb,
2023                              struct smc_link *lnk)
2024 {
2025         int rc, i, nents, offset, buf_size, size, access_flags;
2026         struct scatterlist *sg;
2027         void *buf;
2028
2029         if (buf_desc->is_map_ib[lnk->link_idx])
2030                 return 0;
2031
2032         if (buf_desc->is_vm) {
2033                 buf = buf_desc->cpu_addr;
2034                 buf_size = buf_desc->len;
2035                 offset = offset_in_page(buf_desc->cpu_addr);
2036                 nents = PAGE_ALIGN(buf_size + offset) / PAGE_SIZE;
2037         } else {
2038                 nents = 1;
2039         }
2040
2041         rc = sg_alloc_table(&buf_desc->sgt[lnk->link_idx], nents, GFP_KERNEL);
2042         if (rc)
2043                 return rc;
2044
2045         if (buf_desc->is_vm) {
2046                 /* virtually contiguous buffer */
2047                 for_each_sg(buf_desc->sgt[lnk->link_idx].sgl, sg, nents, i) {
2048                         size = min_t(int, PAGE_SIZE - offset, buf_size);
2049                         sg_set_page(sg, vmalloc_to_page(buf), size, offset);
2050                         buf += size / sizeof(*buf);
2051                         buf_size -= size;
2052                         offset = 0;
2053                 }
2054         } else {
2055                 /* physically contiguous buffer */
2056                 sg_set_buf(buf_desc->sgt[lnk->link_idx].sgl,
2057                            buf_desc->cpu_addr, buf_desc->len);
2058         }
2059
2060         /* map sg table to DMA address */
2061         rc = smc_ib_buf_map_sg(lnk, buf_desc,
2062                                is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2063         /* SMC protocol depends on mapping to one DMA address only */
2064         if (rc != nents) {
2065                 rc = -EAGAIN;
2066                 goto free_table;
2067         }
2068
2069         buf_desc->is_dma_need_sync |=
2070                 smc_ib_is_sg_need_sync(lnk, buf_desc) << lnk->link_idx;
2071
2072         if (is_rmb || buf_desc->is_vm) {
2073                 /* create a new memory region for the RMB or vzalloced sndbuf */
2074                 access_flags = is_rmb ?
2075                                IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
2076                                IB_ACCESS_LOCAL_WRITE;
2077
2078                 rc = smc_ib_get_memory_region(lnk->roce_pd, access_flags,
2079                                               buf_desc, lnk->link_idx);
2080                 if (rc)
2081                         goto buf_unmap;
2082                 smc_ib_sync_sg_for_device(lnk, buf_desc,
2083                                           is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2084         }
2085         buf_desc->is_map_ib[lnk->link_idx] = true;
2086         return 0;
2087
2088 buf_unmap:
2089         smc_ib_buf_unmap_sg(lnk, buf_desc,
2090                             is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2091 free_table:
2092         sg_free_table(&buf_desc->sgt[lnk->link_idx]);
2093         return rc;
2094 }
2095
2096 /* register a new buf on IB device, rmb or vzalloced sndbuf
2097  * must be called under lgr->llc_conf_mutex lock
2098  */
2099 int smcr_link_reg_buf(struct smc_link *link, struct smc_buf_desc *buf_desc)
2100 {
2101         if (list_empty(&link->lgr->list))
2102                 return -ENOLINK;
2103         if (!buf_desc->is_reg_mr[link->link_idx]) {
2104                 /* register memory region for new buf */
2105                 if (buf_desc->is_vm)
2106                         buf_desc->mr[link->link_idx]->iova =
2107                                 (uintptr_t)buf_desc->cpu_addr;
2108                 if (smc_wr_reg_send(link, buf_desc->mr[link->link_idx])) {
2109                         buf_desc->is_reg_err = true;
2110                         return -EFAULT;
2111                 }
2112                 buf_desc->is_reg_mr[link->link_idx] = true;
2113         }
2114         return 0;
2115 }
2116
2117 static int _smcr_buf_map_lgr(struct smc_link *lnk, struct rw_semaphore *lock,
2118                              struct list_head *lst, bool is_rmb)
2119 {
2120         struct smc_buf_desc *buf_desc, *bf;
2121         int rc = 0;
2122
2123         down_write(lock);
2124         list_for_each_entry_safe(buf_desc, bf, lst, list) {
2125                 if (!buf_desc->used)
2126                         continue;
2127                 rc = smcr_buf_map_link(buf_desc, is_rmb, lnk);
2128                 if (rc)
2129                         goto out;
2130         }
2131 out:
2132         up_write(lock);
2133         return rc;
2134 }
2135
2136 /* map all used buffers of lgr for a new link */
2137 int smcr_buf_map_lgr(struct smc_link *lnk)
2138 {
2139         struct smc_link_group *lgr = lnk->lgr;
2140         int i, rc = 0;
2141
2142         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2143                 rc = _smcr_buf_map_lgr(lnk, &lgr->rmbs_lock,
2144                                        &lgr->rmbs[i], true);
2145                 if (rc)
2146                         return rc;
2147                 rc = _smcr_buf_map_lgr(lnk, &lgr->sndbufs_lock,
2148                                        &lgr->sndbufs[i], false);
2149                 if (rc)
2150                         return rc;
2151         }
2152         return 0;
2153 }
2154
2155 /* register all used buffers of lgr for a new link,
2156  * must be called under lgr->llc_conf_mutex lock
2157  */
2158 int smcr_buf_reg_lgr(struct smc_link *lnk)
2159 {
2160         struct smc_link_group *lgr = lnk->lgr;
2161         struct smc_buf_desc *buf_desc, *bf;
2162         int i, rc = 0;
2163
2164         /* reg all RMBs for a new link */
2165         down_write(&lgr->rmbs_lock);
2166         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2167                 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list) {
2168                         if (!buf_desc->used)
2169                                 continue;
2170                         rc = smcr_link_reg_buf(lnk, buf_desc);
2171                         if (rc) {
2172                                 up_write(&lgr->rmbs_lock);
2173                                 return rc;
2174                         }
2175                 }
2176         }
2177         up_write(&lgr->rmbs_lock);
2178
2179         if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
2180                 return rc;
2181
2182         /* reg all vzalloced sndbufs for a new link */
2183         down_write(&lgr->sndbufs_lock);
2184         for (i = 0; i < SMC_RMBE_SIZES; i++) {
2185                 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i], list) {
2186                         if (!buf_desc->used || !buf_desc->is_vm)
2187                                 continue;
2188                         rc = smcr_link_reg_buf(lnk, buf_desc);
2189                         if (rc) {
2190                                 up_write(&lgr->sndbufs_lock);
2191                                 return rc;
2192                         }
2193                 }
2194         }
2195         up_write(&lgr->sndbufs_lock);
2196         return rc;
2197 }
2198
2199 static struct smc_buf_desc *smcr_new_buf_create(struct smc_link_group *lgr,
2200                                                 bool is_rmb, int bufsize)
2201 {
2202         struct smc_buf_desc *buf_desc;
2203
2204         /* try to alloc a new buffer */
2205         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
2206         if (!buf_desc)
2207                 return ERR_PTR(-ENOMEM);
2208
2209         switch (lgr->buf_type) {
2210         case SMCR_PHYS_CONT_BUFS:
2211         case SMCR_MIXED_BUFS:
2212                 buf_desc->order = get_order(bufsize);
2213                 buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN |
2214                                               __GFP_NOMEMALLOC | __GFP_COMP |
2215                                               __GFP_NORETRY | __GFP_ZERO,
2216                                               buf_desc->order);
2217                 if (buf_desc->pages) {
2218                         buf_desc->cpu_addr =
2219                                 (void *)page_address(buf_desc->pages);
2220                         buf_desc->len = bufsize;
2221                         buf_desc->is_vm = false;
2222                         break;
2223                 }
2224                 if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
2225                         goto out;
2226                 fallthrough;    // try virtually continguous buf
2227         case SMCR_VIRT_CONT_BUFS:
2228                 buf_desc->order = get_order(bufsize);
2229                 buf_desc->cpu_addr = vzalloc(PAGE_SIZE << buf_desc->order);
2230                 if (!buf_desc->cpu_addr)
2231                         goto out;
2232                 buf_desc->pages = NULL;
2233                 buf_desc->len = bufsize;
2234                 buf_desc->is_vm = true;
2235                 break;
2236         }
2237         return buf_desc;
2238
2239 out:
2240         kfree(buf_desc);
2241         return ERR_PTR(-EAGAIN);
2242 }
2243
2244 /* map buf_desc on all usable links,
2245  * unused buffers stay mapped as long as the link is up
2246  */
2247 static int smcr_buf_map_usable_links(struct smc_link_group *lgr,
2248                                      struct smc_buf_desc *buf_desc, bool is_rmb)
2249 {
2250         int i, rc = 0, cnt = 0;
2251
2252         /* protect against parallel link reconfiguration */
2253         down_read(&lgr->llc_conf_mutex);
2254         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2255                 struct smc_link *lnk = &lgr->lnk[i];
2256
2257                 if (!smc_link_usable(lnk))
2258                         continue;
2259                 if (smcr_buf_map_link(buf_desc, is_rmb, lnk)) {
2260                         rc = -ENOMEM;
2261                         goto out;
2262                 }
2263                 cnt++;
2264         }
2265 out:
2266         up_read(&lgr->llc_conf_mutex);
2267         if (!rc && !cnt)
2268                 rc = -EINVAL;
2269         return rc;
2270 }
2271
2272 static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr,
2273                                                 bool is_dmb, int bufsize)
2274 {
2275         struct smc_buf_desc *buf_desc;
2276         int rc;
2277
2278         /* try to alloc a new DMB */
2279         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
2280         if (!buf_desc)
2281                 return ERR_PTR(-ENOMEM);
2282         if (is_dmb) {
2283                 rc = smc_ism_register_dmb(lgr, bufsize, buf_desc);
2284                 if (rc) {
2285                         kfree(buf_desc);
2286                         if (rc == -ENOMEM)
2287                                 return ERR_PTR(-EAGAIN);
2288                         if (rc == -ENOSPC)
2289                                 return ERR_PTR(-ENOSPC);
2290                         return ERR_PTR(-EIO);
2291                 }
2292                 buf_desc->pages = virt_to_page(buf_desc->cpu_addr);
2293                 /* CDC header stored in buf. So, pretend it was smaller */
2294                 buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg);
2295         } else {
2296                 buf_desc->cpu_addr = kzalloc(bufsize, GFP_KERNEL |
2297                                              __GFP_NOWARN | __GFP_NORETRY |
2298                                              __GFP_NOMEMALLOC);
2299                 if (!buf_desc->cpu_addr) {
2300                         kfree(buf_desc);
2301                         return ERR_PTR(-EAGAIN);
2302                 }
2303                 buf_desc->len = bufsize;
2304         }
2305         return buf_desc;
2306 }
2307
2308 static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb)
2309 {
2310         struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM);
2311         struct smc_connection *conn = &smc->conn;
2312         struct smc_link_group *lgr = conn->lgr;
2313         struct list_head *buf_list;
2314         int bufsize, bufsize_comp;
2315         struct rw_semaphore *lock;      /* lock buffer list */
2316         bool is_dgraded = false;
2317
2318         if (is_rmb)
2319                 /* use socket recv buffer size (w/o overhead) as start value */
2320                 bufsize = smc->sk.sk_rcvbuf / 2;
2321         else
2322                 /* use socket send buffer size (w/o overhead) as start value */
2323                 bufsize = smc->sk.sk_sndbuf / 2;
2324
2325         for (bufsize_comp = smc_compress_bufsize(bufsize, is_smcd, is_rmb);
2326              bufsize_comp >= 0; bufsize_comp--) {
2327                 if (is_rmb) {
2328                         lock = &lgr->rmbs_lock;
2329                         buf_list = &lgr->rmbs[bufsize_comp];
2330                 } else {
2331                         lock = &lgr->sndbufs_lock;
2332                         buf_list = &lgr->sndbufs[bufsize_comp];
2333                 }
2334                 bufsize = smc_uncompress_bufsize(bufsize_comp);
2335
2336                 /* check for reusable slot in the link group */
2337                 buf_desc = smc_buf_get_slot(bufsize_comp, lock, buf_list);
2338                 if (buf_desc) {
2339                         buf_desc->is_dma_need_sync = 0;
2340                         SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
2341                         SMC_STAT_BUF_REUSE(smc, is_smcd, is_rmb);
2342                         break; /* found reusable slot */
2343                 }
2344
2345                 if (is_smcd)
2346                         buf_desc = smcd_new_buf_create(lgr, is_rmb, bufsize);
2347                 else
2348                         buf_desc = smcr_new_buf_create(lgr, is_rmb, bufsize);
2349
2350                 if (PTR_ERR(buf_desc) == -ENOMEM)
2351                         break;
2352                 if (IS_ERR(buf_desc)) {
2353                         if (!is_dgraded) {
2354                                 is_dgraded = true;
2355                                 SMC_STAT_RMB_DOWNGRADED(smc, is_smcd, is_rmb);
2356                         }
2357                         continue;
2358                 }
2359
2360                 SMC_STAT_RMB_ALLOC(smc, is_smcd, is_rmb);
2361                 SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
2362                 buf_desc->used = 1;
2363                 down_write(lock);
2364                 list_add(&buf_desc->list, buf_list);
2365                 up_write(lock);
2366                 break; /* found */
2367         }
2368
2369         if (IS_ERR(buf_desc))
2370                 return PTR_ERR(buf_desc);
2371
2372         if (!is_smcd) {
2373                 if (smcr_buf_map_usable_links(lgr, buf_desc, is_rmb)) {
2374                         smcr_buf_unuse(buf_desc, is_rmb, lgr);
2375                         return -ENOMEM;
2376                 }
2377         }
2378
2379         if (is_rmb) {
2380                 conn->rmb_desc = buf_desc;
2381                 conn->rmbe_size_comp = bufsize_comp;
2382                 smc->sk.sk_rcvbuf = bufsize * 2;
2383                 atomic_set(&conn->bytes_to_rcv, 0);
2384                 conn->rmbe_update_limit =
2385                         smc_rmb_wnd_update_limit(buf_desc->len);
2386                 if (is_smcd)
2387                         smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */
2388         } else {
2389                 conn->sndbuf_desc = buf_desc;
2390                 smc->sk.sk_sndbuf = bufsize * 2;
2391                 atomic_set(&conn->sndbuf_space, bufsize);
2392         }
2393         return 0;
2394 }
2395
2396 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
2397 {
2398         if (!conn->sndbuf_desc->is_dma_need_sync)
2399                 return;
2400         if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd ||
2401             !smc_link_active(conn->lnk))
2402                 return;
2403         smc_ib_sync_sg_for_device(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
2404 }
2405
2406 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
2407 {
2408         int i;
2409
2410         if (!conn->rmb_desc->is_dma_need_sync)
2411                 return;
2412         if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd)
2413                 return;
2414         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2415                 if (!smc_link_active(&conn->lgr->lnk[i]))
2416                         continue;
2417                 smc_ib_sync_sg_for_cpu(&conn->lgr->lnk[i], conn->rmb_desc,
2418                                        DMA_FROM_DEVICE);
2419         }
2420 }
2421
2422 /* create the send and receive buffer for an SMC socket;
2423  * receive buffers are called RMBs;
2424  * (even though the SMC protocol allows more than one RMB-element per RMB,
2425  * the Linux implementation uses just one RMB-element per RMB, i.e. uses an
2426  * extra RMB for every connection in a link group
2427  */
2428 int smc_buf_create(struct smc_sock *smc, bool is_smcd)
2429 {
2430         int rc;
2431
2432         /* create send buffer */
2433         rc = __smc_buf_create(smc, is_smcd, false);
2434         if (rc)
2435                 return rc;
2436         /* create rmb */
2437         rc = __smc_buf_create(smc, is_smcd, true);
2438         if (rc) {
2439                 down_write(&smc->conn.lgr->sndbufs_lock);
2440                 list_del(&smc->conn.sndbuf_desc->list);
2441                 up_write(&smc->conn.lgr->sndbufs_lock);
2442                 smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc);
2443                 smc->conn.sndbuf_desc = NULL;
2444         }
2445         return rc;
2446 }
2447
2448 static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
2449 {
2450         int i;
2451
2452         for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) {
2453                 if (!test_and_set_bit(i, lgr->rtokens_used_mask))
2454                         return i;
2455         }
2456         return -ENOSPC;
2457 }
2458
2459 static int smc_rtoken_find_by_link(struct smc_link_group *lgr, int lnk_idx,
2460                                    u32 rkey)
2461 {
2462         int i;
2463
2464         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2465                 if (test_bit(i, lgr->rtokens_used_mask) &&
2466                     lgr->rtokens[i][lnk_idx].rkey == rkey)
2467                         return i;
2468         }
2469         return -ENOENT;
2470 }
2471
2472 /* set rtoken for a new link to an existing rmb */
2473 void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
2474                     __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey)
2475 {
2476         int rtok_idx;
2477
2478         rtok_idx = smc_rtoken_find_by_link(lgr, link_idx, ntohl(nw_rkey_known));
2479         if (rtok_idx == -ENOENT)
2480                 return;
2481         lgr->rtokens[rtok_idx][link_idx_new].rkey = ntohl(nw_rkey);
2482         lgr->rtokens[rtok_idx][link_idx_new].dma_addr = be64_to_cpu(nw_vaddr);
2483 }
2484
2485 /* set rtoken for a new link whose link_id is given */
2486 void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
2487                      __be64 nw_vaddr, __be32 nw_rkey)
2488 {
2489         u64 dma_addr = be64_to_cpu(nw_vaddr);
2490         u32 rkey = ntohl(nw_rkey);
2491         bool found = false;
2492         int link_idx;
2493
2494         for (link_idx = 0; link_idx < SMC_LINKS_PER_LGR_MAX; link_idx++) {
2495                 if (lgr->lnk[link_idx].link_id == link_id) {
2496                         found = true;
2497                         break;
2498                 }
2499         }
2500         if (!found)
2501                 return;
2502         lgr->rtokens[rtok_idx][link_idx].rkey = rkey;
2503         lgr->rtokens[rtok_idx][link_idx].dma_addr = dma_addr;
2504 }
2505
2506 /* add a new rtoken from peer */
2507 int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey)
2508 {
2509         struct smc_link_group *lgr = smc_get_lgr(lnk);
2510         u64 dma_addr = be64_to_cpu(nw_vaddr);
2511         u32 rkey = ntohl(nw_rkey);
2512         int i;
2513
2514         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2515                 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2516                     lgr->rtokens[i][lnk->link_idx].dma_addr == dma_addr &&
2517                     test_bit(i, lgr->rtokens_used_mask)) {
2518                         /* already in list */
2519                         return i;
2520                 }
2521         }
2522         i = smc_rmb_reserve_rtoken_idx(lgr);
2523         if (i < 0)
2524                 return i;
2525         lgr->rtokens[i][lnk->link_idx].rkey = rkey;
2526         lgr->rtokens[i][lnk->link_idx].dma_addr = dma_addr;
2527         return i;
2528 }
2529
2530 /* delete an rtoken from all links */
2531 int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey)
2532 {
2533         struct smc_link_group *lgr = smc_get_lgr(lnk);
2534         u32 rkey = ntohl(nw_rkey);
2535         int i, j;
2536
2537         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2538                 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2539                     test_bit(i, lgr->rtokens_used_mask)) {
2540                         for (j = 0; j < SMC_LINKS_PER_LGR_MAX; j++) {
2541                                 lgr->rtokens[i][j].rkey = 0;
2542                                 lgr->rtokens[i][j].dma_addr = 0;
2543                         }
2544                         clear_bit(i, lgr->rtokens_used_mask);
2545                         return 0;
2546                 }
2547         }
2548         return -ENOENT;
2549 }
2550
2551 /* save rkey and dma_addr received from peer during clc handshake */
2552 int smc_rmb_rtoken_handling(struct smc_connection *conn,
2553                             struct smc_link *lnk,
2554                             struct smc_clc_msg_accept_confirm *clc)
2555 {
2556         conn->rtoken_idx = smc_rtoken_add(lnk, clc->r0.rmb_dma_addr,
2557                                           clc->r0.rmb_rkey);
2558         if (conn->rtoken_idx < 0)
2559                 return conn->rtoken_idx;
2560         return 0;
2561 }
2562
2563 static void smc_core_going_away(void)
2564 {
2565         struct smc_ib_device *smcibdev;
2566         struct smcd_dev *smcd;
2567
2568         mutex_lock(&smc_ib_devices.mutex);
2569         list_for_each_entry(smcibdev, &smc_ib_devices.list, list) {
2570                 int i;
2571
2572                 for (i = 0; i < SMC_MAX_PORTS; i++)
2573                         set_bit(i, smcibdev->ports_going_away);
2574         }
2575         mutex_unlock(&smc_ib_devices.mutex);
2576
2577         mutex_lock(&smcd_dev_list.mutex);
2578         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2579                 smcd->going_away = 1;
2580         }
2581         mutex_unlock(&smcd_dev_list.mutex);
2582 }
2583
2584 /* Clean up all SMC link groups */
2585 static void smc_lgrs_shutdown(void)
2586 {
2587         struct smcd_dev *smcd;
2588
2589         smc_core_going_away();
2590
2591         smc_smcr_terminate_all(NULL);
2592
2593         mutex_lock(&smcd_dev_list.mutex);
2594         list_for_each_entry(smcd, &smcd_dev_list.list, list)
2595                 smc_smcd_terminate_all(smcd);
2596         mutex_unlock(&smcd_dev_list.mutex);
2597 }
2598
2599 static int smc_core_reboot_event(struct notifier_block *this,
2600                                  unsigned long event, void *ptr)
2601 {
2602         smc_lgrs_shutdown();
2603         smc_ib_unregister_client();
2604         smc_ism_exit();
2605         return 0;
2606 }
2607
2608 static struct notifier_block smc_reboot_notifier = {
2609         .notifier_call = smc_core_reboot_event,
2610 };
2611
2612 int __init smc_core_init(void)
2613 {
2614         return register_reboot_notifier(&smc_reboot_notifier);
2615 }
2616
2617 /* Called (from smc_exit) when module is removed */
2618 void smc_core_exit(void)
2619 {
2620         unregister_reboot_notifier(&smc_reboot_notifier);
2621         smc_lgrs_shutdown();
2622 }