net/smc/smc_core.c

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