net/smc/smc_llc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
   4  *
   5  *  Link Layer Control (LLC)
   6  *
   7  *  Copyright IBM Corp. 2016
   8  *
   9  *  Author(s):  Klaus Wacker <[email protected]>
  10  *              Ursula Braun <[email protected]>
  11  */
  12
  13 #include <net/tcp.h>
  14 #include <rdma/ib_verbs.h>
  15
  16 #include "smc.h"
  17 #include "smc_core.h"
  18 #include "smc_clc.h"
  19 #include "smc_llc.h"
  20 #include "smc_pnet.h"
  21
  22 #define SMC_LLC_DATA_LEN                40
  23
  24 struct smc_llc_hdr {
  25         struct smc_wr_rx_hdr common;
  26         union {
  27                 struct {
  28                         u8 length;      /* 44 */
  29         #if defined(__BIG_ENDIAN_BITFIELD)
  30                         u8 reserved:4,
  31                            add_link_rej_rsn:4;
  32 #elif defined(__LITTLE_ENDIAN_BITFIELD)
  33                         u8 add_link_rej_rsn:4,
  34                            reserved:4;
  35 #endif
  36                 };
  37                 u16 length_v2;  /* 44 - 8192*/
  38         };
  39         u8 flags;
  40 } __packed;             /* format defined in
  41                          * IBM Shared Memory Communications Version 2
  42                          * (https://www.ibm.com/support/pages/node/6326337)
  43                          */
  44
  45 #define SMC_LLC_FLAG_NO_RMBE_EYEC       0x03
  46
  47 struct smc_llc_msg_confirm_link {       /* type 0x01 */
  48         struct smc_llc_hdr hd;
  49         u8 sender_mac[ETH_ALEN];
  50         u8 sender_gid[SMC_GID_SIZE];
  51         u8 sender_qp_num[3];
  52         u8 link_num;
  53         u8 link_uid[SMC_LGR_ID_SIZE];
  54         u8 max_links;
  55         u8 reserved[9];
  56 };
  57
  58 #define SMC_LLC_FLAG_ADD_LNK_REJ        0x40
  59 #define SMC_LLC_REJ_RSN_NO_ALT_PATH     1
  60
  61 #define SMC_LLC_ADD_LNK_MAX_LINKS       2
  62
  63 struct smc_llc_msg_add_link {           /* type 0x02 */
  64         struct smc_llc_hdr hd;
  65         u8 sender_mac[ETH_ALEN];
  66         u8 reserved2[2];
  67         u8 sender_gid[SMC_GID_SIZE];
  68         u8 sender_qp_num[3];
  69         u8 link_num;
  70 #if defined(__BIG_ENDIAN_BITFIELD)
  71         u8 reserved3 : 4,
  72            qp_mtu   : 4;
  73 #elif defined(__LITTLE_ENDIAN_BITFIELD)
  74         u8 qp_mtu   : 4,
  75            reserved3 : 4;
  76 #endif
  77         u8 initial_psn[3];
  78         u8 reserved[8];
  79 };
  80
  81 struct smc_llc_msg_add_link_cont_rt {
  82         __be32 rmb_key;
  83         __be32 rmb_key_new;
  84         __be64 rmb_vaddr_new;
  85 };
  86
  87 struct smc_llc_msg_add_link_v2_ext {
  88 #if defined(__BIG_ENDIAN_BITFIELD)
  89         u8 v2_direct : 1,
  90            reserved  : 7;
  91 #elif defined(__LITTLE_ENDIAN_BITFIELD)
  92         u8 reserved  : 7,
  93            v2_direct : 1;
  94 #endif
  95         u8 reserved2;
  96         u8 client_target_gid[SMC_GID_SIZE];
  97         u8 reserved3[8];
  98         u16 num_rkeys;
  99         struct smc_llc_msg_add_link_cont_rt rt[];
 100 } __packed;             /* format defined in
 101                          * IBM Shared Memory Communications Version 2
 102                          * (https://www.ibm.com/support/pages/node/6326337)
 103                          */
 104
 105 struct smc_llc_msg_req_add_link_v2 {
 106         struct smc_llc_hdr hd;
 107         u8 reserved[20];
 108         u8 gid_cnt;
 109         u8 reserved2[3];
 110         u8 gid[][SMC_GID_SIZE];
 111 };
 112
 113 #define SMC_LLC_RKEYS_PER_CONT_MSG      2
 114
 115 struct smc_llc_msg_add_link_cont {      /* type 0x03 */
 116         struct smc_llc_hdr hd;
 117         u8 link_num;
 118         u8 num_rkeys;
 119         u8 reserved2[2];
 120         struct smc_llc_msg_add_link_cont_rt rt[SMC_LLC_RKEYS_PER_CONT_MSG];
 121         u8 reserved[4];
 122 } __packed;                     /* format defined in RFC7609 */
 123
 124 #define SMC_LLC_FLAG_DEL_LINK_ALL       0x40
 125 #define SMC_LLC_FLAG_DEL_LINK_ORDERLY   0x20
 126
 127 struct smc_llc_msg_del_link {           /* type 0x04 */
 128         struct smc_llc_hdr hd;
 129         u8 link_num;
 130         __be32 reason;
 131         u8 reserved[35];
 132 } __packed;                     /* format defined in RFC7609 */
 133
 134 struct smc_llc_msg_test_link {          /* type 0x07 */
 135         struct smc_llc_hdr hd;
 136         u8 user_data[16];
 137         u8 reserved[24];
 138 };
 139
 140 struct smc_rmb_rtoken {
 141         union {
 142                 u8 num_rkeys;   /* first rtoken byte of CONFIRM LINK msg */
 143                                 /* is actually the num of rtokens, first */
 144                                 /* rtoken is always for the current link */
 145                 u8 link_id;     /* link id of the rtoken */
 146         };
 147         __be32 rmb_key;
 148         __be64 rmb_vaddr;
 149 } __packed;                     /* format defined in RFC7609 */
 150
 151 #define SMC_LLC_RKEYS_PER_MSG           3
 152 #define SMC_LLC_RKEYS_PER_MSG_V2        255
 153
 154 struct smc_llc_msg_confirm_rkey {       /* type 0x06 */
 155         struct smc_llc_hdr hd;
 156         struct smc_rmb_rtoken rtoken[SMC_LLC_RKEYS_PER_MSG];
 157         u8 reserved;
 158 };
 159
 160 #define SMC_LLC_DEL_RKEY_MAX    8
 161 #define SMC_LLC_FLAG_RKEY_RETRY 0x10
 162 #define SMC_LLC_FLAG_RKEY_NEG   0x20
 163
 164 struct smc_llc_msg_delete_rkey {        /* type 0x09 */
 165         struct smc_llc_hdr hd;
 166         u8 num_rkeys;
 167         u8 err_mask;
 168         u8 reserved[2];
 169         __be32 rkey[8];
 170         u8 reserved2[4];
 171 };
 172
 173 struct smc_llc_msg_delete_rkey_v2 {     /* type 0x29 */
 174         struct smc_llc_hdr hd;
 175         u8 num_rkeys;
 176         u8 num_inval_rkeys;
 177         u8 reserved[2];
 178         __be32 rkey[];
 179 };
 180
 181 union smc_llc_msg {
 182         struct smc_llc_msg_confirm_link confirm_link;
 183         struct smc_llc_msg_add_link add_link;
 184         struct smc_llc_msg_req_add_link_v2 req_add_link;
 185         struct smc_llc_msg_add_link_cont add_link_cont;
 186         struct smc_llc_msg_del_link delete_link;
 187
 188         struct smc_llc_msg_confirm_rkey confirm_rkey;
 189         struct smc_llc_msg_delete_rkey delete_rkey;
 190
 191         struct smc_llc_msg_test_link test_link;
 192         struct {
 193                 struct smc_llc_hdr hdr;
 194                 u8 data[SMC_LLC_DATA_LEN];
 195         } raw;
 196 };
 197
 198 #define SMC_LLC_FLAG_RESP               0x80
 199
 200 struct smc_llc_qentry {
 201         struct list_head list;
 202         struct smc_link *link;
 203         union smc_llc_msg msg;
 204 };
 205
 206 static void smc_llc_enqueue(struct smc_link *link, union smc_llc_msg *llc);
 207
 208 struct smc_llc_qentry *smc_llc_flow_qentry_clr(struct smc_llc_flow *flow)
 209 {
 210         struct smc_llc_qentry *qentry = flow->qentry;
 211
 212         flow->qentry = NULL;
 213         return qentry;
 214 }
 215
 216 void smc_llc_flow_qentry_del(struct smc_llc_flow *flow)
 217 {
 218         struct smc_llc_qentry *qentry;
 219
 220         if (flow->qentry) {
 221                 qentry = flow->qentry;
 222                 flow->qentry = NULL;
 223                 kfree(qentry);
 224         }
 225 }
 226
 227 static inline void smc_llc_flow_qentry_set(struct smc_llc_flow *flow,
 228                                            struct smc_llc_qentry *qentry)
 229 {
 230         flow->qentry = qentry;
 231 }
 232
 233 static void smc_llc_flow_parallel(struct smc_link_group *lgr, u8 flow_type,
 234                                   struct smc_llc_qentry *qentry)
 235 {
 236         u8 msg_type = qentry->msg.raw.hdr.common.llc_type;
 237
 238         if ((msg_type == SMC_LLC_ADD_LINK || msg_type == SMC_LLC_DELETE_LINK) &&
 239             flow_type != msg_type && !lgr->delayed_event) {
 240                 lgr->delayed_event = qentry;
 241                 return;
 242         }
 243         /* drop parallel or already-in-progress llc requests */
 244         if (flow_type != msg_type)
 245                 pr_warn_once("smc: SMC-R lg %*phN net %llu dropped parallel "
 246                              "LLC msg: msg %d flow %d role %d\n",
 247                              SMC_LGR_ID_SIZE, &lgr->id,
 248                              lgr->net->net_cookie,
 249                              qentry->msg.raw.hdr.common.type,
 250                              flow_type, lgr->role);
 251         kfree(qentry);
 252 }
 253
 254 /* try to start a new llc flow, initiated by an incoming llc msg */
 255 static bool smc_llc_flow_start(struct smc_llc_flow *flow,
 256                                struct smc_llc_qentry *qentry)
 257 {
 258         struct smc_link_group *lgr = qentry->link->lgr;
 259
 260         spin_lock_bh(&lgr->llc_flow_lock);
 261         if (flow->type) {
 262                 /* a flow is already active */
 263                 smc_llc_flow_parallel(lgr, flow->type, qentry);
 264                 spin_unlock_bh(&lgr->llc_flow_lock);
 265                 return false;
 266         }
 267         switch (qentry->msg.raw.hdr.common.llc_type) {
 268         case SMC_LLC_ADD_LINK:
 269                 flow->type = SMC_LLC_FLOW_ADD_LINK;
 270                 break;
 271         case SMC_LLC_DELETE_LINK:
 272                 flow->type = SMC_LLC_FLOW_DEL_LINK;
 273                 break;
 274         case SMC_LLC_CONFIRM_RKEY:
 275         case SMC_LLC_DELETE_RKEY:
 276                 flow->type = SMC_LLC_FLOW_RKEY;
 277                 break;
 278         default:
 279                 flow->type = SMC_LLC_FLOW_NONE;
 280         }
 281         smc_llc_flow_qentry_set(flow, qentry);
 282         spin_unlock_bh(&lgr->llc_flow_lock);
 283         return true;
 284 }
 285
 286 /* start a new local llc flow, wait till current flow finished */
 287 int smc_llc_flow_initiate(struct smc_link_group *lgr,
 288                           enum smc_llc_flowtype type)
 289 {
 290         enum smc_llc_flowtype allowed_remote = SMC_LLC_FLOW_NONE;
 291         int rc;
 292
 293         /* all flows except confirm_rkey and delete_rkey are exclusive,
 294          * confirm/delete rkey flows can run concurrently (local and remote)
 295          */
 296         if (type == SMC_LLC_FLOW_RKEY)
 297                 allowed_remote = SMC_LLC_FLOW_RKEY;
 298 again:
 299         if (list_empty(&lgr->list))
 300                 return -ENODEV;
 301         spin_lock_bh(&lgr->llc_flow_lock);
 302         if (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE &&
 303             (lgr->llc_flow_rmt.type == SMC_LLC_FLOW_NONE ||
 304              lgr->llc_flow_rmt.type == allowed_remote)) {
 305                 lgr->llc_flow_lcl.type = type;
 306                 spin_unlock_bh(&lgr->llc_flow_lock);
 307                 return 0;
 308         }
 309         spin_unlock_bh(&lgr->llc_flow_lock);
 310         rc = wait_event_timeout(lgr->llc_flow_waiter, (list_empty(&lgr->list) ||
 311                                 (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE &&
 312                                  (lgr->llc_flow_rmt.type == SMC_LLC_FLOW_NONE ||
 313                                   lgr->llc_flow_rmt.type == allowed_remote))),
 314                                 SMC_LLC_WAIT_TIME * 10);
 315         if (!rc)
 316                 return -ETIMEDOUT;
 317         goto again;
 318 }
 319
 320 /* finish the current llc flow */
 321 void smc_llc_flow_stop(struct smc_link_group *lgr, struct smc_llc_flow *flow)
 322 {
 323         spin_lock_bh(&lgr->llc_flow_lock);
 324         memset(flow, 0, sizeof(*flow));
 325         flow->type = SMC_LLC_FLOW_NONE;
 326         spin_unlock_bh(&lgr->llc_flow_lock);
 327         if (!list_empty(&lgr->list) && lgr->delayed_event &&
 328             flow == &lgr->llc_flow_lcl)
 329                 schedule_work(&lgr->llc_event_work);
 330         else
 331                 wake_up(&lgr->llc_flow_waiter);
 332 }
 333
 334 /* lnk is optional and used for early wakeup when link goes down, useful in
 335  * cases where we wait for a response on the link after we sent a request
 336  */
 337 struct smc_llc_qentry *smc_llc_wait(struct smc_link_group *lgr,
 338                                     struct smc_link *lnk,
 339                                     int time_out, u8 exp_msg)
 340 {
 341         struct smc_llc_flow *flow = &lgr->llc_flow_lcl;
 342         u8 rcv_msg;
 343
 344         wait_event_timeout(lgr->llc_msg_waiter,
 345                            (flow->qentry ||
 346                             (lnk && !smc_link_usable(lnk)) ||
 347                             list_empty(&lgr->list)),
 348                            time_out);
 349         if (!flow->qentry ||
 350             (lnk && !smc_link_usable(lnk)) || list_empty(&lgr->list)) {
 351                 smc_llc_flow_qentry_del(flow);
 352                 goto out;
 353         }
 354         rcv_msg = flow->qentry->msg.raw.hdr.common.llc_type;
 355         if (exp_msg && rcv_msg != exp_msg) {
 356                 if (exp_msg == SMC_LLC_ADD_LINK &&
 357                     rcv_msg == SMC_LLC_DELETE_LINK) {
 358                         /* flow_start will delay the unexpected msg */
 359                         smc_llc_flow_start(&lgr->llc_flow_lcl,
 360                                            smc_llc_flow_qentry_clr(flow));
 361                         return NULL;
 362                 }
 363                 pr_warn_once("smc: SMC-R lg %*phN net %llu dropped unexpected LLC msg: "
 364                              "msg %d exp %d flow %d role %d flags %x\n",
 365                              SMC_LGR_ID_SIZE, &lgr->id, lgr->net->net_cookie,
 366                              rcv_msg, exp_msg,
 367                              flow->type, lgr->role,
 368                              flow->qentry->msg.raw.hdr.flags);
 369                 smc_llc_flow_qentry_del(flow);
 370         }
 371 out:
 372         return flow->qentry;
 373 }
 374
 375 /********************************** send *************************************/
 376
 377 struct smc_llc_tx_pend {
 378 };
 379
 380 /* handler for send/transmission completion of an LLC msg */
 381 static void smc_llc_tx_handler(struct smc_wr_tx_pend_priv *pend,
 382                                struct smc_link *link,
 383                                enum ib_wc_status wc_status)
 384 {
 385         /* future work: handle wc_status error for recovery and failover */
 386 }
 387
 388 /**
 389  * smc_llc_add_pending_send() - add LLC control message to pending WQE transmits
 390  * @link: Pointer to SMC link used for sending LLC control message.
 391  * @wr_buf: Out variable returning pointer to work request payload buffer.
 392  * @pend: Out variable returning pointer to private pending WR tracking.
 393  *        It's the context the transmit complete handler will get.
 394  *
 395  * Reserves and pre-fills an entry for a pending work request send/tx.
 396  * Used by mid-level smc_llc_send_msg() to prepare for later actual send/tx.
 397  * Can sleep due to smc_get_ctrl_buf (if not in softirq context).
 398  *
 399  * Return: 0 on success, otherwise an error value.
 400  */
 401 static int smc_llc_add_pending_send(struct smc_link *link,
 402                                     struct smc_wr_buf **wr_buf,
 403                                     struct smc_wr_tx_pend_priv **pend)
 404 {
 405         int rc;
 406
 407         rc = smc_wr_tx_get_free_slot(link, smc_llc_tx_handler, wr_buf, NULL,
 408                                      pend);
 409         if (rc < 0)
 410                 return rc;
 411         BUILD_BUG_ON_MSG(
 412                 sizeof(union smc_llc_msg) > SMC_WR_BUF_SIZE,
 413                 "must increase SMC_WR_BUF_SIZE to at least sizeof(struct smc_llc_msg)");
 414         BUILD_BUG_ON_MSG(
 415                 sizeof(union smc_llc_msg) != SMC_WR_TX_SIZE,
 416                 "must adapt SMC_WR_TX_SIZE to sizeof(struct smc_llc_msg); if not all smc_wr upper layer protocols use the same message size any more, must start to set link->wr_tx_sges[i].length on each individual smc_wr_tx_send()");
 417         BUILD_BUG_ON_MSG(
 418                 sizeof(struct smc_llc_tx_pend) > SMC_WR_TX_PEND_PRIV_SIZE,
 419                 "must increase SMC_WR_TX_PEND_PRIV_SIZE to at least sizeof(struct smc_llc_tx_pend)");
 420         return 0;
 421 }
 422
 423 static int smc_llc_add_pending_send_v2(struct smc_link *link,
 424                                        struct smc_wr_v2_buf **wr_buf,
 425                                        struct smc_wr_tx_pend_priv **pend)
 426 {
 427         int rc;
 428
 429         rc = smc_wr_tx_get_v2_slot(link, smc_llc_tx_handler, wr_buf, pend);
 430         if (rc < 0)
 431                 return rc;
 432         return 0;
 433 }
 434
 435 static void smc_llc_init_msg_hdr(struct smc_llc_hdr *hdr,
 436                                  struct smc_link_group *lgr, size_t len)
 437 {
 438         if (lgr->smc_version == SMC_V2) {
 439                 hdr->common.llc_version = SMC_V2;
 440                 hdr->length_v2 = len;
 441         } else {
 442                 hdr->common.llc_version = 0;
 443                 hdr->length = len;
 444         }
 445 }
 446
 447 /* high-level API to send LLC confirm link */
 448 int smc_llc_send_confirm_link(struct smc_link *link,
 449                               enum smc_llc_reqresp reqresp)
 450 {
 451         struct smc_llc_msg_confirm_link *confllc;
 452         struct smc_wr_tx_pend_priv *pend;
 453         struct smc_wr_buf *wr_buf;
 454         int rc;
 455
 456         if (!smc_wr_tx_link_hold(link))
 457                 return -ENOLINK;
 458         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 459         if (rc)
 460                 goto put_out;
 461         confllc = (struct smc_llc_msg_confirm_link *)wr_buf;
 462         memset(confllc, 0, sizeof(*confllc));
 463         confllc->hd.common.llc_type = SMC_LLC_CONFIRM_LINK;
 464         smc_llc_init_msg_hdr(&confllc->hd, link->lgr, sizeof(*confllc));
 465         confllc->hd.flags |= SMC_LLC_FLAG_NO_RMBE_EYEC;
 466         if (reqresp == SMC_LLC_RESP)
 467                 confllc->hd.flags |= SMC_LLC_FLAG_RESP;
 468         memcpy(confllc->sender_mac, link->smcibdev->mac[link->ibport - 1],
 469                ETH_ALEN);
 470         memcpy(confllc->sender_gid, link->gid, SMC_GID_SIZE);
 471         hton24(confllc->sender_qp_num, link->roce_qp->qp_num);
 472         confllc->link_num = link->link_id;
 473         memcpy(confllc->link_uid, link->link_uid, SMC_LGR_ID_SIZE);
 474         confllc->max_links = SMC_LLC_ADD_LNK_MAX_LINKS;
 475         /* send llc message */
 476         rc = smc_wr_tx_send(link, pend);
 477 put_out:
 478         smc_wr_tx_link_put(link);
 479         return rc;
 480 }
 481
 482 /* send LLC confirm rkey request */
 483 static int smc_llc_send_confirm_rkey(struct smc_link *send_link,
 484                                      struct smc_buf_desc *rmb_desc)
 485 {
 486         struct smc_llc_msg_confirm_rkey *rkeyllc;
 487         struct smc_wr_tx_pend_priv *pend;
 488         struct smc_wr_buf *wr_buf;
 489         struct smc_link *link;
 490         int i, rc, rtok_ix;
 491
 492         if (!smc_wr_tx_link_hold(send_link))
 493                 return -ENOLINK;
 494         rc = smc_llc_add_pending_send(send_link, &wr_buf, &pend);
 495         if (rc)
 496                 goto put_out;
 497         rkeyllc = (struct smc_llc_msg_confirm_rkey *)wr_buf;
 498         memset(rkeyllc, 0, sizeof(*rkeyllc));
 499         rkeyllc->hd.common.llc_type = SMC_LLC_CONFIRM_RKEY;
 500         smc_llc_init_msg_hdr(&rkeyllc->hd, send_link->lgr, sizeof(*rkeyllc));
 501
 502         rtok_ix = 1;
 503         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 504                 link = &send_link->lgr->lnk[i];
 505                 if (smc_link_active(link) && link != send_link) {
 506                         rkeyllc->rtoken[rtok_ix].link_id = link->link_id;
 507                         rkeyllc->rtoken[rtok_ix].rmb_key =
 508                                 htonl(rmb_desc->mr_rx[link->link_idx]->rkey);
 509                         rkeyllc->rtoken[rtok_ix].rmb_vaddr = cpu_to_be64(
 510                                 (u64)sg_dma_address(
 511                                         rmb_desc->sgt[link->link_idx].sgl));
 512                         rtok_ix++;
 513                 }
 514         }
 515         /* rkey of send_link is in rtoken[0] */
 516         rkeyllc->rtoken[0].num_rkeys = rtok_ix - 1;
 517         rkeyllc->rtoken[0].rmb_key =
 518                 htonl(rmb_desc->mr_rx[send_link->link_idx]->rkey);
 519         rkeyllc->rtoken[0].rmb_vaddr = cpu_to_be64(
 520                 (u64)sg_dma_address(rmb_desc->sgt[send_link->link_idx].sgl));
 521         /* send llc message */
 522         rc = smc_wr_tx_send(send_link, pend);
 523 put_out:
 524         smc_wr_tx_link_put(send_link);
 525         return rc;
 526 }
 527
 528 /* send LLC delete rkey request */
 529 static int smc_llc_send_delete_rkey(struct smc_link *link,
 530                                     struct smc_buf_desc *rmb_desc)
 531 {
 532         struct smc_llc_msg_delete_rkey *rkeyllc;
 533         struct smc_wr_tx_pend_priv *pend;
 534         struct smc_wr_buf *wr_buf;
 535         int rc;
 536
 537         if (!smc_wr_tx_link_hold(link))
 538                 return -ENOLINK;
 539         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 540         if (rc)
 541                 goto put_out;
 542         rkeyllc = (struct smc_llc_msg_delete_rkey *)wr_buf;
 543         memset(rkeyllc, 0, sizeof(*rkeyllc));
 544         rkeyllc->hd.common.llc_type = SMC_LLC_DELETE_RKEY;
 545         smc_llc_init_msg_hdr(&rkeyllc->hd, link->lgr, sizeof(*rkeyllc));
 546         rkeyllc->num_rkeys = 1;
 547         rkeyllc->rkey[0] = htonl(rmb_desc->mr_rx[link->link_idx]->rkey);
 548         /* send llc message */
 549         rc = smc_wr_tx_send(link, pend);
 550 put_out:
 551         smc_wr_tx_link_put(link);
 552         return rc;
 553 }
 554
 555 /* return first buffer from any of the next buf lists */
 556 static struct smc_buf_desc *_smc_llc_get_next_rmb(struct smc_link_group *lgr,
 557                                                   int *buf_lst)
 558 {
 559         struct smc_buf_desc *buf_pos;
 560
 561         while (*buf_lst < SMC_RMBE_SIZES) {
 562                 buf_pos = list_first_entry_or_null(&lgr->rmbs[*buf_lst],
 563                                                    struct smc_buf_desc, list);
 564                 if (buf_pos)
 565                         return buf_pos;
 566                 (*buf_lst)++;
 567         }
 568         return NULL;
 569 }
 570
 571 /* return next rmb from buffer lists */
 572 static struct smc_buf_desc *smc_llc_get_next_rmb(struct smc_link_group *lgr,
 573                                                  int *buf_lst,
 574                                                  struct smc_buf_desc *buf_pos)
 575 {
 576         struct smc_buf_desc *buf_next;
 577
 578         if (!buf_pos || list_is_last(&buf_pos->list, &lgr->rmbs[*buf_lst])) {
 579                 (*buf_lst)++;
 580                 return _smc_llc_get_next_rmb(lgr, buf_lst);
 581         }
 582         buf_next = list_next_entry(buf_pos, list);
 583         return buf_next;
 584 }
 585
 586 static struct smc_buf_desc *smc_llc_get_first_rmb(struct smc_link_group *lgr,
 587                                                   int *buf_lst)
 588 {
 589         *buf_lst = 0;
 590         return smc_llc_get_next_rmb(lgr, buf_lst, NULL);
 591 }
 592
 593 static int smc_llc_fill_ext_v2(struct smc_llc_msg_add_link_v2_ext *ext,
 594                                struct smc_link *link, struct smc_link *link_new)
 595 {
 596         struct smc_link_group *lgr = link->lgr;
 597         struct smc_buf_desc *buf_pos;
 598         int prim_lnk_idx, lnk_idx, i;
 599         struct smc_buf_desc *rmb;
 600         int len = sizeof(*ext);
 601         int buf_lst;
 602
 603         ext->v2_direct = !lgr->uses_gateway;
 604         memcpy(ext->client_target_gid, link_new->gid, SMC_GID_SIZE);
 605
 606         prim_lnk_idx = link->link_idx;
 607         lnk_idx = link_new->link_idx;
 608         mutex_lock(&lgr->rmbs_lock);
 609         ext->num_rkeys = lgr->conns_num;
 610         if (!ext->num_rkeys)
 611                 goto out;
 612         buf_pos = smc_llc_get_first_rmb(lgr, &buf_lst);
 613         for (i = 0; i < ext->num_rkeys; i++) {
 614                 if (!buf_pos)
 615                         break;
 616                 rmb = buf_pos;
 617                 ext->rt[i].rmb_key = htonl(rmb->mr_rx[prim_lnk_idx]->rkey);
 618                 ext->rt[i].rmb_key_new = htonl(rmb->mr_rx[lnk_idx]->rkey);
 619                 ext->rt[i].rmb_vaddr_new =
 620                         cpu_to_be64((u64)sg_dma_address(rmb->sgt[lnk_idx].sgl));
 621                 buf_pos = smc_llc_get_next_rmb(lgr, &buf_lst, buf_pos);
 622                 while (buf_pos && !(buf_pos)->used)
 623                         buf_pos = smc_llc_get_next_rmb(lgr, &buf_lst, buf_pos);
 624         }
 625         len += i * sizeof(ext->rt[0]);
 626 out:
 627         mutex_unlock(&lgr->rmbs_lock);
 628         return len;
 629 }
 630
 631 /* send ADD LINK request or response */
 632 int smc_llc_send_add_link(struct smc_link *link, u8 mac[], u8 gid[],
 633                           struct smc_link *link_new,
 634                           enum smc_llc_reqresp reqresp)
 635 {
 636         struct smc_llc_msg_add_link_v2_ext *ext = NULL;
 637         struct smc_llc_msg_add_link *addllc;
 638         struct smc_wr_tx_pend_priv *pend;
 639         int len = sizeof(*addllc);
 640         int rc;
 641
 642         if (!smc_wr_tx_link_hold(link))
 643                 return -ENOLINK;
 644         if (link->lgr->smc_version == SMC_V2) {
 645                 struct smc_wr_v2_buf *wr_buf;
 646
 647                 rc = smc_llc_add_pending_send_v2(link, &wr_buf, &pend);
 648                 if (rc)
 649                         goto put_out;
 650                 addllc = (struct smc_llc_msg_add_link *)wr_buf;
 651                 ext = (struct smc_llc_msg_add_link_v2_ext *)
 652                                                 &wr_buf->raw[sizeof(*addllc)];
 653                 memset(ext, 0, SMC_WR_TX_SIZE);
 654         } else {
 655                 struct smc_wr_buf *wr_buf;
 656
 657                 rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 658                 if (rc)
 659                         goto put_out;
 660                 addllc = (struct smc_llc_msg_add_link *)wr_buf;
 661         }
 662
 663         memset(addllc, 0, sizeof(*addllc));
 664         addllc->hd.common.llc_type = SMC_LLC_ADD_LINK;
 665         if (reqresp == SMC_LLC_RESP)
 666                 addllc->hd.flags |= SMC_LLC_FLAG_RESP;
 667         memcpy(addllc->sender_mac, mac, ETH_ALEN);
 668         memcpy(addllc->sender_gid, gid, SMC_GID_SIZE);
 669         if (link_new) {
 670                 addllc->link_num = link_new->link_id;
 671                 hton24(addllc->sender_qp_num, link_new->roce_qp->qp_num);
 672                 hton24(addllc->initial_psn, link_new->psn_initial);
 673                 if (reqresp == SMC_LLC_REQ)
 674                         addllc->qp_mtu = link_new->path_mtu;
 675                 else
 676                         addllc->qp_mtu = min(link_new->path_mtu,
 677                                              link_new->peer_mtu);
 678         }
 679         if (ext && link_new)
 680                 len += smc_llc_fill_ext_v2(ext, link, link_new);
 681         smc_llc_init_msg_hdr(&addllc->hd, link->lgr, len);
 682         /* send llc message */
 683         if (link->lgr->smc_version == SMC_V2)
 684                 rc = smc_wr_tx_v2_send(link, pend, len);
 685         else
 686                 rc = smc_wr_tx_send(link, pend);
 687 put_out:
 688         smc_wr_tx_link_put(link);
 689         return rc;
 690 }
 691
 692 /* send DELETE LINK request or response */
 693 int smc_llc_send_delete_link(struct smc_link *link, u8 link_del_id,
 694                              enum smc_llc_reqresp reqresp, bool orderly,
 695                              u32 reason)
 696 {
 697         struct smc_llc_msg_del_link *delllc;
 698         struct smc_wr_tx_pend_priv *pend;
 699         struct smc_wr_buf *wr_buf;
 700         int rc;
 701
 702         if (!smc_wr_tx_link_hold(link))
 703                 return -ENOLINK;
 704         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 705         if (rc)
 706                 goto put_out;
 707         delllc = (struct smc_llc_msg_del_link *)wr_buf;
 708
 709         memset(delllc, 0, sizeof(*delllc));
 710         delllc->hd.common.llc_type = SMC_LLC_DELETE_LINK;
 711         smc_llc_init_msg_hdr(&delllc->hd, link->lgr, sizeof(*delllc));
 712         if (reqresp == SMC_LLC_RESP)
 713                 delllc->hd.flags |= SMC_LLC_FLAG_RESP;
 714         if (orderly)
 715                 delllc->hd.flags |= SMC_LLC_FLAG_DEL_LINK_ORDERLY;
 716         if (link_del_id)
 717                 delllc->link_num = link_del_id;
 718         else
 719                 delllc->hd.flags |= SMC_LLC_FLAG_DEL_LINK_ALL;
 720         delllc->reason = htonl(reason);
 721         /* send llc message */
 722         rc = smc_wr_tx_send(link, pend);
 723 put_out:
 724         smc_wr_tx_link_put(link);
 725         return rc;
 726 }
 727
 728 /* send LLC test link request */
 729 static int smc_llc_send_test_link(struct smc_link *link, u8 user_data[16])
 730 {
 731         struct smc_llc_msg_test_link *testllc;
 732         struct smc_wr_tx_pend_priv *pend;
 733         struct smc_wr_buf *wr_buf;
 734         int rc;
 735
 736         if (!smc_wr_tx_link_hold(link))
 737                 return -ENOLINK;
 738         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 739         if (rc)
 740                 goto put_out;
 741         testllc = (struct smc_llc_msg_test_link *)wr_buf;
 742         memset(testllc, 0, sizeof(*testllc));
 743         testllc->hd.common.llc_type = SMC_LLC_TEST_LINK;
 744         smc_llc_init_msg_hdr(&testllc->hd, link->lgr, sizeof(*testllc));
 745         memcpy(testllc->user_data, user_data, sizeof(testllc->user_data));
 746         /* send llc message */
 747         rc = smc_wr_tx_send(link, pend);
 748 put_out:
 749         smc_wr_tx_link_put(link);
 750         return rc;
 751 }
 752
 753 /* schedule an llc send on link, may wait for buffers */
 754 static int smc_llc_send_message(struct smc_link *link, void *llcbuf)
 755 {
 756         struct smc_wr_tx_pend_priv *pend;
 757         struct smc_wr_buf *wr_buf;
 758         int rc;
 759
 760         if (!smc_wr_tx_link_hold(link))
 761                 return -ENOLINK;
 762         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 763         if (rc)
 764                 goto put_out;
 765         memcpy(wr_buf, llcbuf, sizeof(union smc_llc_msg));
 766         rc = smc_wr_tx_send(link, pend);
 767 put_out:
 768         smc_wr_tx_link_put(link);
 769         return rc;
 770 }
 771
 772 /* schedule an llc send on link, may wait for buffers,
 773  * and wait for send completion notification.
 774  * @return 0 on success
 775  */
 776 static int smc_llc_send_message_wait(struct smc_link *link, void *llcbuf)
 777 {
 778         struct smc_wr_tx_pend_priv *pend;
 779         struct smc_wr_buf *wr_buf;
 780         int rc;
 781
 782         if (!smc_wr_tx_link_hold(link))
 783                 return -ENOLINK;
 784         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 785         if (rc)
 786                 goto put_out;
 787         memcpy(wr_buf, llcbuf, sizeof(union smc_llc_msg));
 788         rc = smc_wr_tx_send_wait(link, pend, SMC_LLC_WAIT_TIME);
 789 put_out:
 790         smc_wr_tx_link_put(link);
 791         return rc;
 792 }
 793
 794 /********************************* receive ***********************************/
 795
 796 static int smc_llc_alloc_alt_link(struct smc_link_group *lgr,
 797                                   enum smc_lgr_type lgr_new_t)
 798 {
 799         int i;
 800
 801         if (lgr->type == SMC_LGR_SYMMETRIC ||
 802             (lgr->type != SMC_LGR_SINGLE &&
 803              (lgr_new_t == SMC_LGR_ASYMMETRIC_LOCAL ||
 804               lgr_new_t == SMC_LGR_ASYMMETRIC_PEER)))
 805                 return -EMLINK;
 806
 807         if (lgr_new_t == SMC_LGR_ASYMMETRIC_LOCAL ||
 808             lgr_new_t == SMC_LGR_ASYMMETRIC_PEER) {
 809                 for (i = SMC_LINKS_PER_LGR_MAX - 1; i >= 0; i--)
 810                         if (lgr->lnk[i].state == SMC_LNK_UNUSED)
 811                                 return i;
 812         } else {
 813                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
 814                         if (lgr->lnk[i].state == SMC_LNK_UNUSED)
 815                                 return i;
 816         }
 817         return -EMLINK;
 818 }
 819
 820 /* send one add_link_continue msg */
 821 static int smc_llc_add_link_cont(struct smc_link *link,
 822                                  struct smc_link *link_new, u8 *num_rkeys_todo,
 823                                  int *buf_lst, struct smc_buf_desc **buf_pos)
 824 {
 825         struct smc_llc_msg_add_link_cont *addc_llc;
 826         struct smc_link_group *lgr = link->lgr;
 827         int prim_lnk_idx, lnk_idx, i, rc;
 828         struct smc_wr_tx_pend_priv *pend;
 829         struct smc_wr_buf *wr_buf;
 830         struct smc_buf_desc *rmb;
 831         u8 n;
 832
 833         if (!smc_wr_tx_link_hold(link))
 834                 return -ENOLINK;
 835         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 836         if (rc)
 837                 goto put_out;
 838         addc_llc = (struct smc_llc_msg_add_link_cont *)wr_buf;
 839         memset(addc_llc, 0, sizeof(*addc_llc));
 840
 841         prim_lnk_idx = link->link_idx;
 842         lnk_idx = link_new->link_idx;
 843         addc_llc->link_num = link_new->link_id;
 844         addc_llc->num_rkeys = *num_rkeys_todo;
 845         n = *num_rkeys_todo;
 846         for (i = 0; i < min_t(u8, n, SMC_LLC_RKEYS_PER_CONT_MSG); i++) {
 847                 if (!*buf_pos) {
 848                         addc_llc->num_rkeys = addc_llc->num_rkeys -
 849                                               *num_rkeys_todo;
 850                         *num_rkeys_todo = 0;
 851                         break;
 852                 }
 853                 rmb = *buf_pos;
 854
 855                 addc_llc->rt[i].rmb_key = htonl(rmb->mr_rx[prim_lnk_idx]->rkey);
 856                 addc_llc->rt[i].rmb_key_new = htonl(rmb->mr_rx[lnk_idx]->rkey);
 857                 addc_llc->rt[i].rmb_vaddr_new =
 858                         cpu_to_be64((u64)sg_dma_address(rmb->sgt[lnk_idx].sgl));
 859
 860                 (*num_rkeys_todo)--;
 861                 *buf_pos = smc_llc_get_next_rmb(lgr, buf_lst, *buf_pos);
 862                 while (*buf_pos && !(*buf_pos)->used)
 863                         *buf_pos = smc_llc_get_next_rmb(lgr, buf_lst, *buf_pos);
 864         }
 865         addc_llc->hd.common.llc_type = SMC_LLC_ADD_LINK_CONT;
 866         addc_llc->hd.length = sizeof(struct smc_llc_msg_add_link_cont);
 867         if (lgr->role == SMC_CLNT)
 868                 addc_llc->hd.flags |= SMC_LLC_FLAG_RESP;
 869         rc = smc_wr_tx_send(link, pend);
 870 put_out:
 871         smc_wr_tx_link_put(link);
 872         return rc;
 873 }
 874
 875 static int smc_llc_cli_rkey_exchange(struct smc_link *link,
 876                                      struct smc_link *link_new)
 877 {
 878         struct smc_llc_msg_add_link_cont *addc_llc;
 879         struct smc_link_group *lgr = link->lgr;
 880         u8 max, num_rkeys_send, num_rkeys_recv;
 881         struct smc_llc_qentry *qentry;
 882         struct smc_buf_desc *buf_pos;
 883         int buf_lst;
 884         int rc = 0;
 885         int i;
 886
 887         mutex_lock(&lgr->rmbs_lock);
 888         num_rkeys_send = lgr->conns_num;
 889         buf_pos = smc_llc_get_first_rmb(lgr, &buf_lst);
 890         do {
 891                 qentry = smc_llc_wait(lgr, NULL, SMC_LLC_WAIT_TIME,
 892                                       SMC_LLC_ADD_LINK_CONT);
 893                 if (!qentry) {
 894                         rc = -ETIMEDOUT;
 895                         break;
 896                 }
 897                 addc_llc = &qentry->msg.add_link_cont;
 898                 num_rkeys_recv = addc_llc->num_rkeys;
 899                 max = min_t(u8, num_rkeys_recv, SMC_LLC_RKEYS_PER_CONT_MSG);
 900                 for (i = 0; i < max; i++) {
 901                         smc_rtoken_set(lgr, link->link_idx, link_new->link_idx,
 902                                        addc_llc->rt[i].rmb_key,
 903                                        addc_llc->rt[i].rmb_vaddr_new,
 904                                        addc_llc->rt[i].rmb_key_new);
 905                         num_rkeys_recv--;
 906                 }
 907                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
 908                 rc = smc_llc_add_link_cont(link, link_new, &num_rkeys_send,
 909                                            &buf_lst, &buf_pos);
 910                 if (rc)
 911                         break;
 912         } while (num_rkeys_send || num_rkeys_recv);
 913
 914         mutex_unlock(&lgr->rmbs_lock);
 915         return rc;
 916 }
 917
 918 /* prepare and send an add link reject response */
 919 static int smc_llc_cli_add_link_reject(struct smc_llc_qentry *qentry)
 920 {
 921         qentry->msg.raw.hdr.flags |= SMC_LLC_FLAG_RESP;
 922         qentry->msg.raw.hdr.flags |= SMC_LLC_FLAG_ADD_LNK_REJ;
 923         qentry->msg.raw.hdr.add_link_rej_rsn = SMC_LLC_REJ_RSN_NO_ALT_PATH;
 924         smc_llc_init_msg_hdr(&qentry->msg.raw.hdr, qentry->link->lgr,
 925                              sizeof(qentry->msg));
 926         return smc_llc_send_message(qentry->link, &qentry->msg);
 927 }
 928
 929 static int smc_llc_cli_conf_link(struct smc_link *link,
 930                                  struct smc_init_info *ini,
 931                                  struct smc_link *link_new,
 932                                  enum smc_lgr_type lgr_new_t)
 933 {
 934         struct smc_link_group *lgr = link->lgr;
 935         struct smc_llc_qentry *qentry = NULL;
 936         int rc = 0;
 937
 938         /* receive CONFIRM LINK request over RoCE fabric */
 939         qentry = smc_llc_wait(lgr, NULL, SMC_LLC_WAIT_FIRST_TIME, 0);
 940         if (!qentry) {
 941                 rc = smc_llc_send_delete_link(link, link_new->link_id,
 942                                               SMC_LLC_REQ, false,
 943                                               SMC_LLC_DEL_LOST_PATH);
 944                 return -ENOLINK;
 945         }
 946         if (qentry->msg.raw.hdr.common.llc_type != SMC_LLC_CONFIRM_LINK) {
 947                 /* received DELETE_LINK instead */
 948                 qentry->msg.raw.hdr.flags |= SMC_LLC_FLAG_RESP;
 949                 smc_llc_send_message(link, &qentry->msg);
 950                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
 951                 return -ENOLINK;
 952         }
 953         smc_llc_save_peer_uid(qentry);
 954         smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
 955
 956         rc = smc_ib_modify_qp_rts(link_new);
 957         if (rc) {
 958                 smc_llc_send_delete_link(link, link_new->link_id, SMC_LLC_REQ,
 959                                          false, SMC_LLC_DEL_LOST_PATH);
 960                 return -ENOLINK;
 961         }
 962         smc_wr_remember_qp_attr(link_new);
 963
 964         rc = smcr_buf_reg_lgr(link_new);
 965         if (rc) {
 966                 smc_llc_send_delete_link(link, link_new->link_id, SMC_LLC_REQ,
 967                                          false, SMC_LLC_DEL_LOST_PATH);
 968                 return -ENOLINK;
 969         }
 970
 971         /* send CONFIRM LINK response over RoCE fabric */
 972         rc = smc_llc_send_confirm_link(link_new, SMC_LLC_RESP);
 973         if (rc) {
 974                 smc_llc_send_delete_link(link, link_new->link_id, SMC_LLC_REQ,
 975                                          false, SMC_LLC_DEL_LOST_PATH);
 976                 return -ENOLINK;
 977         }
 978         smc_llc_link_active(link_new);
 979         if (lgr_new_t == SMC_LGR_ASYMMETRIC_LOCAL ||
 980             lgr_new_t == SMC_LGR_ASYMMETRIC_PEER)
 981                 smcr_lgr_set_type_asym(lgr, lgr_new_t, link_new->link_idx);
 982         else
 983                 smcr_lgr_set_type(lgr, lgr_new_t);
 984         return 0;
 985 }
 986
 987 static void smc_llc_save_add_link_rkeys(struct smc_link *link,
 988                                         struct smc_link *link_new)
 989 {
 990         struct smc_llc_msg_add_link_v2_ext *ext;
 991         struct smc_link_group *lgr = link->lgr;
 992         int max, i;
 993
 994         ext = (struct smc_llc_msg_add_link_v2_ext *)((u8 *)lgr->wr_rx_buf_v2 +
 995                                                      SMC_WR_TX_SIZE);
 996         max = min_t(u8, ext->num_rkeys, SMC_LLC_RKEYS_PER_MSG_V2);
 997         mutex_lock(&lgr->rmbs_lock);
 998         for (i = 0; i < max; i++) {
 999                 smc_rtoken_set(lgr, link->link_idx, link_new->link_idx,
1000                                ext->rt[i].rmb_key,
1001                                ext->rt[i].rmb_vaddr_new,
1002                                ext->rt[i].rmb_key_new);
1003         }
1004         mutex_unlock(&lgr->rmbs_lock);
1005 }
1006
1007 static void smc_llc_save_add_link_info(struct smc_link *link,
1008                                        struct smc_llc_msg_add_link *add_llc)
1009 {
1010         link->peer_qpn = ntoh24(add_llc->sender_qp_num);
1011         memcpy(link->peer_gid, add_llc->sender_gid, SMC_GID_SIZE);
1012         memcpy(link->peer_mac, add_llc->sender_mac, ETH_ALEN);
1013         link->peer_psn = ntoh24(add_llc->initial_psn);
1014         link->peer_mtu = add_llc->qp_mtu;
1015 }
1016
1017 /* as an SMC client, process an add link request */
1018 int smc_llc_cli_add_link(struct smc_link *link, struct smc_llc_qentry *qentry)
1019 {
1020         struct smc_llc_msg_add_link *llc = &qentry->msg.add_link;
1021         enum smc_lgr_type lgr_new_t = SMC_LGR_SYMMETRIC;
1022         struct smc_link_group *lgr = smc_get_lgr(link);
1023         struct smc_init_info *ini = NULL;
1024         struct smc_link *lnk_new = NULL;
1025         int lnk_idx, rc = 0;
1026
1027         if (!llc->qp_mtu)
1028                 goto out_reject;
1029
1030         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1031         if (!ini) {
1032                 rc = -ENOMEM;
1033                 goto out_reject;
1034         }
1035
1036         ini->vlan_id = lgr->vlan_id;
1037         if (lgr->smc_version == SMC_V2) {
1038                 ini->check_smcrv2 = true;
1039                 ini->smcrv2.saddr = lgr->saddr;
1040                 ini->smcrv2.daddr = smc_ib_gid_to_ipv4(llc->sender_gid);
1041         }
1042         smc_pnet_find_alt_roce(lgr, ini, link->smcibdev);
1043         if (!memcmp(llc->sender_gid, link->peer_gid, SMC_GID_SIZE) &&
1044             (lgr->smc_version == SMC_V2 ||
1045              !memcmp(llc->sender_mac, link->peer_mac, ETH_ALEN))) {
1046                 if (!ini->ib_dev && !ini->smcrv2.ib_dev_v2)
1047                         goto out_reject;
1048                 lgr_new_t = SMC_LGR_ASYMMETRIC_PEER;
1049         }
1050         if (lgr->smc_version == SMC_V2 && !ini->smcrv2.ib_dev_v2) {
1051                 lgr_new_t = SMC_LGR_ASYMMETRIC_LOCAL;
1052                 ini->smcrv2.ib_dev_v2 = link->smcibdev;
1053                 ini->smcrv2.ib_port_v2 = link->ibport;
1054         } else if (lgr->smc_version < SMC_V2 && !ini->ib_dev) {
1055                 lgr_new_t = SMC_LGR_ASYMMETRIC_LOCAL;
1056                 ini->ib_dev = link->smcibdev;
1057                 ini->ib_port = link->ibport;
1058         }
1059         lnk_idx = smc_llc_alloc_alt_link(lgr, lgr_new_t);
1060         if (lnk_idx < 0)
1061                 goto out_reject;
1062         lnk_new = &lgr->lnk[lnk_idx];
1063         rc = smcr_link_init(lgr, lnk_new, lnk_idx, ini);
1064         if (rc)
1065                 goto out_reject;
1066         smc_llc_save_add_link_info(lnk_new, llc);
1067         lnk_new->link_id = llc->link_num;       /* SMC server assigns link id */
1068         smc_llc_link_set_uid(lnk_new);
1069
1070         rc = smc_ib_ready_link(lnk_new);
1071         if (rc)
1072                 goto out_clear_lnk;
1073
1074         rc = smcr_buf_map_lgr(lnk_new);
1075         if (rc)
1076                 goto out_clear_lnk;
1077
1078         rc = smc_llc_send_add_link(link,
1079                                    lnk_new->smcibdev->mac[lnk_new->ibport - 1],
1080                                    lnk_new->gid, lnk_new, SMC_LLC_RESP);
1081         if (rc)
1082                 goto out_clear_lnk;
1083         if (lgr->smc_version == SMC_V2) {
1084                 smc_llc_save_add_link_rkeys(link, lnk_new);
1085         } else {
1086                 rc = smc_llc_cli_rkey_exchange(link, lnk_new);
1087                 if (rc) {
1088                         rc = 0;
1089                         goto out_clear_lnk;
1090                 }
1091         }
1092         rc = smc_llc_cli_conf_link(link, ini, lnk_new, lgr_new_t);
1093         if (!rc)
1094                 goto out;
1095 out_clear_lnk:
1096         lnk_new->state = SMC_LNK_INACTIVE;
1097         smcr_link_clear(lnk_new, false);
1098 out_reject:
1099         smc_llc_cli_add_link_reject(qentry);
1100 out:
1101         kfree(ini);
1102         kfree(qentry);
1103         return rc;
1104 }
1105
1106 static void smc_llc_send_request_add_link(struct smc_link *link)
1107 {
1108         struct smc_llc_msg_req_add_link_v2 *llc;
1109         struct smc_wr_tx_pend_priv *pend;
1110         struct smc_wr_v2_buf *wr_buf;
1111         struct smc_gidlist gidlist;
1112         int rc, len, i;
1113
1114         if (!smc_wr_tx_link_hold(link))
1115                 return;
1116         if (link->lgr->type == SMC_LGR_SYMMETRIC ||
1117             link->lgr->type == SMC_LGR_ASYMMETRIC_PEER)
1118                 goto put_out;
1119
1120         smc_fill_gid_list(link->lgr, &gidlist, link->smcibdev, link->gid);
1121         if (gidlist.len <= 1)
1122                 goto put_out;
1123
1124         rc = smc_llc_add_pending_send_v2(link, &wr_buf, &pend);
1125         if (rc)
1126                 goto put_out;
1127         llc = (struct smc_llc_msg_req_add_link_v2 *)wr_buf;
1128         memset(llc, 0, SMC_WR_TX_SIZE);
1129
1130         llc->hd.common.llc_type = SMC_LLC_REQ_ADD_LINK;
1131         for (i = 0; i < gidlist.len; i++)
1132                 memcpy(llc->gid[i], gidlist.list[i], sizeof(gidlist.list[0]));
1133         llc->gid_cnt = gidlist.len;
1134         len = sizeof(*llc) + (gidlist.len * sizeof(gidlist.list[0]));
1135         smc_llc_init_msg_hdr(&llc->hd, link->lgr, len);
1136         rc = smc_wr_tx_v2_send(link, pend, len);
1137         if (!rc)
1138                 /* set REQ_ADD_LINK flow and wait for response from peer */
1139                 link->lgr->llc_flow_lcl.type = SMC_LLC_FLOW_REQ_ADD_LINK;
1140 put_out:
1141         smc_wr_tx_link_put(link);
1142 }
1143
1144 /* as an SMC client, invite server to start the add_link processing */
1145 static void smc_llc_cli_add_link_invite(struct smc_link *link,
1146                                         struct smc_llc_qentry *qentry)
1147 {
1148         struct smc_link_group *lgr = smc_get_lgr(link);
1149         struct smc_init_info *ini = NULL;
1150
1151         if (lgr->smc_version == SMC_V2) {
1152                 smc_llc_send_request_add_link(link);
1153                 goto out;
1154         }
1155
1156         if (lgr->type == SMC_LGR_SYMMETRIC ||
1157             lgr->type == SMC_LGR_ASYMMETRIC_PEER)
1158                 goto out;
1159
1160         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1161         if (!ini)
1162                 goto out;
1163
1164         ini->vlan_id = lgr->vlan_id;
1165         smc_pnet_find_alt_roce(lgr, ini, link->smcibdev);
1166         if (!ini->ib_dev)
1167                 goto out;
1168
1169         smc_llc_send_add_link(link, ini->ib_dev->mac[ini->ib_port - 1],
1170                               ini->ib_gid, NULL, SMC_LLC_REQ);
1171 out:
1172         kfree(ini);
1173         kfree(qentry);
1174 }
1175
1176 static bool smc_llc_is_empty_llc_message(union smc_llc_msg *llc)
1177 {
1178         int i;
1179
1180         for (i = 0; i < ARRAY_SIZE(llc->raw.data); i++)
1181                 if (llc->raw.data[i])
1182                         return false;
1183         return true;
1184 }
1185
1186 static bool smc_llc_is_local_add_link(union smc_llc_msg *llc)
1187 {
1188         if (llc->raw.hdr.common.llc_type == SMC_LLC_ADD_LINK &&
1189             smc_llc_is_empty_llc_message(llc))
1190                 return true;
1191         return false;
1192 }
1193
1194 static void smc_llc_process_cli_add_link(struct smc_link_group *lgr)
1195 {
1196         struct smc_llc_qentry *qentry;
1197
1198         qentry = smc_llc_flow_qentry_clr(&lgr->llc_flow_lcl);
1199
1200         mutex_lock(&lgr->llc_conf_mutex);
1201         if (smc_llc_is_local_add_link(&qentry->msg))
1202                 smc_llc_cli_add_link_invite(qentry->link, qentry);
1203         else
1204                 smc_llc_cli_add_link(qentry->link, qentry);
1205         mutex_unlock(&lgr->llc_conf_mutex);
1206 }
1207
1208 static int smc_llc_active_link_count(struct smc_link_group *lgr)
1209 {
1210         int i, link_count = 0;
1211
1212         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1213                 if (!smc_link_active(&lgr->lnk[i]))
1214                         continue;
1215                 link_count++;
1216         }
1217         return link_count;
1218 }
1219
1220 /* find the asymmetric link when 3 links are established  */
1221 static struct smc_link *smc_llc_find_asym_link(struct smc_link_group *lgr)
1222 {
1223         int asym_idx = -ENOENT;
1224         int i, j, k;
1225         bool found;
1226
1227         /* determine asymmetric link */
1228         found = false;
1229         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1230                 for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) {
1231                         if (!smc_link_usable(&lgr->lnk[i]) ||
1232                             !smc_link_usable(&lgr->lnk[j]))
1233                                 continue;
1234                         if (!memcmp(lgr->lnk[i].gid, lgr->lnk[j].gid,
1235                                     SMC_GID_SIZE)) {
1236                                 found = true;   /* asym_lnk is i or j */
1237                                 break;
1238                         }
1239                 }
1240                 if (found)
1241                         break;
1242         }
1243         if (!found)
1244                 goto out; /* no asymmetric link */
1245         for (k = 0; k < SMC_LINKS_PER_LGR_MAX; k++) {
1246                 if (!smc_link_usable(&lgr->lnk[k]))
1247                         continue;
1248                 if (k != i &&
1249                     !memcmp(lgr->lnk[i].peer_gid, lgr->lnk[k].peer_gid,
1250                             SMC_GID_SIZE)) {
1251                         asym_idx = i;
1252                         break;
1253                 }
1254                 if (k != j &&
1255                     !memcmp(lgr->lnk[j].peer_gid, lgr->lnk[k].peer_gid,
1256                             SMC_GID_SIZE)) {
1257                         asym_idx = j;
1258                         break;
1259                 }
1260         }
1261 out:
1262         return (asym_idx < 0) ? NULL : &lgr->lnk[asym_idx];
1263 }
1264
1265 static void smc_llc_delete_asym_link(struct smc_link_group *lgr)
1266 {
1267         struct smc_link *lnk_new = NULL, *lnk_asym;
1268         struct smc_llc_qentry *qentry;
1269         int rc;
1270
1271         lnk_asym = smc_llc_find_asym_link(lgr);
1272         if (!lnk_asym)
1273                 return; /* no asymmetric link */
1274         if (!smc_link_downing(&lnk_asym->state))
1275                 return;
1276         lnk_new = smc_switch_conns(lgr, lnk_asym, false);
1277         smc_wr_tx_wait_no_pending_sends(lnk_asym);
1278         if (!lnk_new)
1279                 goto out_free;
1280         /* change flow type from ADD_LINK into DEL_LINK */
1281         lgr->llc_flow_lcl.type = SMC_LLC_FLOW_DEL_LINK;
1282         rc = smc_llc_send_delete_link(lnk_new, lnk_asym->link_id, SMC_LLC_REQ,
1283                                       true, SMC_LLC_DEL_NO_ASYM_NEEDED);
1284         if (rc) {
1285                 smcr_link_down_cond(lnk_new);
1286                 goto out_free;
1287         }
1288         qentry = smc_llc_wait(lgr, lnk_new, SMC_LLC_WAIT_TIME,
1289                               SMC_LLC_DELETE_LINK);
1290         if (!qentry) {
1291                 smcr_link_down_cond(lnk_new);
1292                 goto out_free;
1293         }
1294         smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1295 out_free:
1296         smcr_link_clear(lnk_asym, true);
1297 }
1298
1299 static int smc_llc_srv_rkey_exchange(struct smc_link *link,
1300                                      struct smc_link *link_new)
1301 {
1302         struct smc_llc_msg_add_link_cont *addc_llc;
1303         struct smc_link_group *lgr = link->lgr;
1304         u8 max, num_rkeys_send, num_rkeys_recv;
1305         struct smc_llc_qentry *qentry = NULL;
1306         struct smc_buf_desc *buf_pos;
1307         int buf_lst;
1308         int rc = 0;
1309         int i;
1310
1311         mutex_lock(&lgr->rmbs_lock);
1312         num_rkeys_send = lgr->conns_num;
1313         buf_pos = smc_llc_get_first_rmb(lgr, &buf_lst);
1314         do {
1315                 smc_llc_add_link_cont(link, link_new, &num_rkeys_send,
1316                                       &buf_lst, &buf_pos);
1317                 qentry = smc_llc_wait(lgr, link, SMC_LLC_WAIT_TIME,
1318                                       SMC_LLC_ADD_LINK_CONT);
1319                 if (!qentry) {
1320                         rc = -ETIMEDOUT;
1321                         goto out;
1322                 }
1323                 addc_llc = &qentry->msg.add_link_cont;
1324                 num_rkeys_recv = addc_llc->num_rkeys;
1325                 max = min_t(u8, num_rkeys_recv, SMC_LLC_RKEYS_PER_CONT_MSG);
1326                 for (i = 0; i < max; i++) {
1327                         smc_rtoken_set(lgr, link->link_idx, link_new->link_idx,
1328                                        addc_llc->rt[i].rmb_key,
1329                                        addc_llc->rt[i].rmb_vaddr_new,
1330                                        addc_llc->rt[i].rmb_key_new);
1331                         num_rkeys_recv--;
1332                 }
1333                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1334         } while (num_rkeys_send || num_rkeys_recv);
1335 out:
1336         mutex_unlock(&lgr->rmbs_lock);
1337         return rc;
1338 }
1339
1340 static int smc_llc_srv_conf_link(struct smc_link *link,
1341                                  struct smc_link *link_new,
1342                                  enum smc_lgr_type lgr_new_t)
1343 {
1344         struct smc_link_group *lgr = link->lgr;
1345         struct smc_llc_qentry *qentry = NULL;
1346         int rc;
1347
1348         /* send CONFIRM LINK request over the RoCE fabric */
1349         rc = smc_llc_send_confirm_link(link_new, SMC_LLC_REQ);
1350         if (rc)
1351                 return -ENOLINK;
1352         /* receive CONFIRM LINK response over the RoCE fabric */
1353         qentry = smc_llc_wait(lgr, link, SMC_LLC_WAIT_FIRST_TIME, 0);
1354         if (!qentry ||
1355             qentry->msg.raw.hdr.common.llc_type != SMC_LLC_CONFIRM_LINK) {
1356                 /* send DELETE LINK */
1357                 smc_llc_send_delete_link(link, link_new->link_id, SMC_LLC_REQ,
1358                                          false, SMC_LLC_DEL_LOST_PATH);
1359                 if (qentry)
1360                         smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1361                 return -ENOLINK;
1362         }
1363         smc_llc_save_peer_uid(qentry);
1364         smc_llc_link_active(link_new);
1365         if (lgr_new_t == SMC_LGR_ASYMMETRIC_LOCAL ||
1366             lgr_new_t == SMC_LGR_ASYMMETRIC_PEER)
1367                 smcr_lgr_set_type_asym(lgr, lgr_new_t, link_new->link_idx);
1368         else
1369                 smcr_lgr_set_type(lgr, lgr_new_t);
1370         smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1371         return 0;
1372 }
1373
1374 static void smc_llc_send_req_add_link_response(struct smc_llc_qentry *qentry)
1375 {
1376         qentry->msg.raw.hdr.flags |= SMC_LLC_FLAG_RESP;
1377         smc_llc_init_msg_hdr(&qentry->msg.raw.hdr, qentry->link->lgr,
1378                              sizeof(qentry->msg));
1379         memset(&qentry->msg.raw.data, 0, sizeof(qentry->msg.raw.data));
1380         smc_llc_send_message(qentry->link, &qentry->msg);
1381 }
1382
1383 int smc_llc_srv_add_link(struct smc_link *link,
1384                          struct smc_llc_qentry *req_qentry)
1385 {
1386         enum smc_lgr_type lgr_new_t = SMC_LGR_SYMMETRIC;
1387         struct smc_link_group *lgr = link->lgr;
1388         struct smc_llc_msg_add_link *add_llc;
1389         struct smc_llc_qentry *qentry = NULL;
1390         bool send_req_add_link_resp = false;
1391         struct smc_link *link_new = NULL;
1392         struct smc_init_info *ini = NULL;
1393         int lnk_idx, rc = 0;
1394
1395         if (req_qentry &&
1396             req_qentry->msg.raw.hdr.common.llc_type == SMC_LLC_REQ_ADD_LINK)
1397                 send_req_add_link_resp = true;
1398
1399         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1400         if (!ini) {
1401                 rc = -ENOMEM;
1402                 goto out;
1403         }
1404
1405         /* ignore client add link recommendation, start new flow */
1406         ini->vlan_id = lgr->vlan_id;
1407         if (lgr->smc_version == SMC_V2) {
1408                 ini->check_smcrv2 = true;
1409                 ini->smcrv2.saddr = lgr->saddr;
1410                 if (send_req_add_link_resp) {
1411                         struct smc_llc_msg_req_add_link_v2 *req_add =
1412                                 &req_qentry->msg.req_add_link;
1413
1414                         ini->smcrv2.daddr = smc_ib_gid_to_ipv4(req_add->gid[0]);
1415                 }
1416         }
1417         smc_pnet_find_alt_roce(lgr, ini, link->smcibdev);
1418         if (lgr->smc_version == SMC_V2 && !ini->smcrv2.ib_dev_v2) {
1419                 lgr_new_t = SMC_LGR_ASYMMETRIC_LOCAL;
1420                 ini->smcrv2.ib_dev_v2 = link->smcibdev;
1421                 ini->smcrv2.ib_port_v2 = link->ibport;
1422         } else if (lgr->smc_version < SMC_V2 && !ini->ib_dev) {
1423                 lgr_new_t = SMC_LGR_ASYMMETRIC_LOCAL;
1424                 ini->ib_dev = link->smcibdev;
1425                 ini->ib_port = link->ibport;
1426         }
1427         lnk_idx = smc_llc_alloc_alt_link(lgr, lgr_new_t);
1428         if (lnk_idx < 0) {
1429                 rc = 0;
1430                 goto out;
1431         }
1432
1433         rc = smcr_link_init(lgr, &lgr->lnk[lnk_idx], lnk_idx, ini);
1434         if (rc)
1435                 goto out;
1436         link_new = &lgr->lnk[lnk_idx];
1437
1438         rc = smcr_buf_map_lgr(link_new);
1439         if (rc)
1440                 goto out_err;
1441
1442         rc = smc_llc_send_add_link(link,
1443                                    link_new->smcibdev->mac[link_new->ibport-1],
1444                                    link_new->gid, link_new, SMC_LLC_REQ);
1445         if (rc)
1446                 goto out_err;
1447         send_req_add_link_resp = false;
1448         /* receive ADD LINK response over the RoCE fabric */
1449         qentry = smc_llc_wait(lgr, link, SMC_LLC_WAIT_TIME, SMC_LLC_ADD_LINK);
1450         if (!qentry) {
1451                 rc = -ETIMEDOUT;
1452                 goto out_err;
1453         }
1454         add_llc = &qentry->msg.add_link;
1455         if (add_llc->hd.flags & SMC_LLC_FLAG_ADD_LNK_REJ) {
1456                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1457                 rc = -ENOLINK;
1458                 goto out_err;
1459         }
1460         if (lgr->type == SMC_LGR_SINGLE &&
1461             (!memcmp(add_llc->sender_gid, link->peer_gid, SMC_GID_SIZE) &&
1462              (lgr->smc_version == SMC_V2 ||
1463               !memcmp(add_llc->sender_mac, link->peer_mac, ETH_ALEN)))) {
1464                 lgr_new_t = SMC_LGR_ASYMMETRIC_PEER;
1465         }
1466         smc_llc_save_add_link_info(link_new, add_llc);
1467         smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1468
1469         rc = smc_ib_ready_link(link_new);
1470         if (rc)
1471                 goto out_err;
1472         rc = smcr_buf_reg_lgr(link_new);
1473         if (rc)
1474                 goto out_err;
1475         if (lgr->smc_version == SMC_V2) {
1476                 smc_llc_save_add_link_rkeys(link, link_new);
1477         } else {
1478                 rc = smc_llc_srv_rkey_exchange(link, link_new);
1479                 if (rc)
1480                         goto out_err;
1481         }
1482         rc = smc_llc_srv_conf_link(link, link_new, lgr_new_t);
1483         if (rc)
1484                 goto out_err;
1485         kfree(ini);
1486         return 0;
1487 out_err:
1488         if (link_new) {
1489                 link_new->state = SMC_LNK_INACTIVE;
1490                 smcr_link_clear(link_new, false);
1491         }
1492 out:
1493         kfree(ini);
1494         if (send_req_add_link_resp)
1495                 smc_llc_send_req_add_link_response(req_qentry);
1496         return rc;
1497 }
1498
1499 static void smc_llc_process_srv_add_link(struct smc_link_group *lgr)
1500 {
1501         struct smc_link *link = lgr->llc_flow_lcl.qentry->link;
1502         struct smc_llc_qentry *qentry;
1503         int rc;
1504
1505         qentry = smc_llc_flow_qentry_clr(&lgr->llc_flow_lcl);
1506
1507         mutex_lock(&lgr->llc_conf_mutex);
1508         rc = smc_llc_srv_add_link(link, qentry);
1509         if (!rc && lgr->type == SMC_LGR_SYMMETRIC) {
1510                 /* delete any asymmetric link */
1511                 smc_llc_delete_asym_link(lgr);
1512         }
1513         mutex_unlock(&lgr->llc_conf_mutex);
1514         kfree(qentry);
1515 }
1516
1517 /* enqueue a local add_link req to trigger a new add_link flow */
1518 void smc_llc_add_link_local(struct smc_link *link)
1519 {
1520         struct smc_llc_msg_add_link add_llc = {};
1521
1522         add_llc.hd.common.llc_type = SMC_LLC_ADD_LINK;
1523         smc_llc_init_msg_hdr(&add_llc.hd, link->lgr, sizeof(add_llc));
1524         /* no dev and port needed */
1525         smc_llc_enqueue(link, (union smc_llc_msg *)&add_llc);
1526 }
1527
1528 /* worker to process an add link message */
1529 static void smc_llc_add_link_work(struct work_struct *work)
1530 {
1531         struct smc_link_group *lgr = container_of(work, struct smc_link_group,
1532                                                   llc_add_link_work);
1533
1534         if (list_empty(&lgr->list)) {
1535                 /* link group is terminating */
1536                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1537                 goto out;
1538         }
1539
1540         if (lgr->role == SMC_CLNT)
1541                 smc_llc_process_cli_add_link(lgr);
1542         else
1543                 smc_llc_process_srv_add_link(lgr);
1544 out:
1545         if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_REQ_ADD_LINK)
1546                 smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
1547 }
1548
1549 /* enqueue a local del_link msg to trigger a new del_link flow,
1550  * called only for role SMC_SERV
1551  */
1552 void smc_llc_srv_delete_link_local(struct smc_link *link, u8 del_link_id)
1553 {
1554         struct smc_llc_msg_del_link del_llc = {};
1555
1556         del_llc.hd.common.llc_type = SMC_LLC_DELETE_LINK;
1557         smc_llc_init_msg_hdr(&del_llc.hd, link->lgr, sizeof(del_llc));
1558         del_llc.link_num = del_link_id;
1559         del_llc.reason = htonl(SMC_LLC_DEL_LOST_PATH);
1560         del_llc.hd.flags |= SMC_LLC_FLAG_DEL_LINK_ORDERLY;
1561         smc_llc_enqueue(link, (union smc_llc_msg *)&del_llc);
1562 }
1563
1564 static void smc_llc_process_cli_delete_link(struct smc_link_group *lgr)
1565 {
1566         struct smc_link *lnk_del = NULL, *lnk_asym, *lnk;
1567         struct smc_llc_msg_del_link *del_llc;
1568         struct smc_llc_qentry *qentry;
1569         int active_links;
1570         int lnk_idx;
1571
1572         qentry = smc_llc_flow_qentry_clr(&lgr->llc_flow_lcl);
1573         lnk = qentry->link;
1574         del_llc = &qentry->msg.delete_link;
1575
1576         if (del_llc->hd.flags & SMC_LLC_FLAG_DEL_LINK_ALL) {
1577                 smc_lgr_terminate_sched(lgr);
1578                 goto out;
1579         }
1580         mutex_lock(&lgr->llc_conf_mutex);
1581         /* delete single link */
1582         for (lnk_idx = 0; lnk_idx < SMC_LINKS_PER_LGR_MAX; lnk_idx++) {
1583                 if (lgr->lnk[lnk_idx].link_id != del_llc->link_num)
1584                         continue;
1585                 lnk_del = &lgr->lnk[lnk_idx];
1586                 break;
1587         }
1588         del_llc->hd.flags |= SMC_LLC_FLAG_RESP;
1589         if (!lnk_del) {
1590                 /* link was not found */
1591                 del_llc->reason = htonl(SMC_LLC_DEL_NOLNK);
1592                 smc_llc_send_message(lnk, &qentry->msg);
1593                 goto out_unlock;
1594         }
1595         lnk_asym = smc_llc_find_asym_link(lgr);
1596
1597         del_llc->reason = 0;
1598         smc_llc_send_message(lnk, &qentry->msg); /* response */
1599
1600         if (smc_link_downing(&lnk_del->state))
1601                 smc_switch_conns(lgr, lnk_del, false);
1602         smcr_link_clear(lnk_del, true);
1603
1604         active_links = smc_llc_active_link_count(lgr);
1605         if (lnk_del == lnk_asym) {
1606                 /* expected deletion of asym link, don't change lgr state */
1607         } else if (active_links == 1) {
1608                 smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
1609         } else if (!active_links) {
1610                 smcr_lgr_set_type(lgr, SMC_LGR_NONE);
1611                 smc_lgr_terminate_sched(lgr);
1612         }
1613 out_unlock:
1614         mutex_unlock(&lgr->llc_conf_mutex);
1615 out:
1616         kfree(qentry);
1617 }
1618
1619 /* try to send a DELETE LINK ALL request on any active link,
1620  * waiting for send completion
1621  */
1622 void smc_llc_send_link_delete_all(struct smc_link_group *lgr, bool ord, u32 rsn)
1623 {
1624         struct smc_llc_msg_del_link delllc = {};
1625         int i;
1626
1627         delllc.hd.common.llc_type = SMC_LLC_DELETE_LINK;
1628         smc_llc_init_msg_hdr(&delllc.hd, lgr, sizeof(delllc));
1629         if (ord)
1630                 delllc.hd.flags |= SMC_LLC_FLAG_DEL_LINK_ORDERLY;
1631         delllc.hd.flags |= SMC_LLC_FLAG_DEL_LINK_ALL;
1632         delllc.reason = htonl(rsn);
1633
1634         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1635                 if (!smc_link_sendable(&lgr->lnk[i]))
1636                         continue;
1637                 if (!smc_llc_send_message_wait(&lgr->lnk[i], &delllc))
1638                         break;
1639         }
1640 }
1641
1642 static void smc_llc_process_srv_delete_link(struct smc_link_group *lgr)
1643 {
1644         struct smc_llc_msg_del_link *del_llc;
1645         struct smc_link *lnk, *lnk_del;
1646         struct smc_llc_qentry *qentry;
1647         int active_links;
1648         int i;
1649
1650         mutex_lock(&lgr->llc_conf_mutex);
1651         qentry = smc_llc_flow_qentry_clr(&lgr->llc_flow_lcl);
1652         lnk = qentry->link;
1653         del_llc = &qentry->msg.delete_link;
1654
1655         if (qentry->msg.delete_link.hd.flags & SMC_LLC_FLAG_DEL_LINK_ALL) {
1656                 /* delete entire lgr */
1657                 smc_llc_send_link_delete_all(lgr, true, ntohl(
1658                                               qentry->msg.delete_link.reason));
1659                 smc_lgr_terminate_sched(lgr);
1660                 goto out;
1661         }
1662         /* delete single link */
1663         lnk_del = NULL;
1664         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1665                 if (lgr->lnk[i].link_id == del_llc->link_num) {
1666                         lnk_del = &lgr->lnk[i];
1667                         break;
1668                 }
1669         }
1670         if (!lnk_del)
1671                 goto out; /* asymmetric link already deleted */
1672
1673         if (smc_link_downing(&lnk_del->state)) {
1674                 if (smc_switch_conns(lgr, lnk_del, false))
1675                         smc_wr_tx_wait_no_pending_sends(lnk_del);
1676         }
1677         if (!list_empty(&lgr->list)) {
1678                 /* qentry is either a request from peer (send it back to
1679                  * initiate the DELETE_LINK processing), or a locally
1680                  * enqueued DELETE_LINK request (forward it)
1681                  */
1682                 if (!smc_llc_send_message(lnk, &qentry->msg)) {
1683                         struct smc_llc_qentry *qentry2;
1684
1685                         qentry2 = smc_llc_wait(lgr, lnk, SMC_LLC_WAIT_TIME,
1686                                                SMC_LLC_DELETE_LINK);
1687                         if (qentry2)
1688                                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1689                 }
1690         }
1691         smcr_link_clear(lnk_del, true);
1692
1693         active_links = smc_llc_active_link_count(lgr);
1694         if (active_links == 1) {
1695                 smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
1696         } else if (!active_links) {
1697                 smcr_lgr_set_type(lgr, SMC_LGR_NONE);
1698                 smc_lgr_terminate_sched(lgr);
1699         }
1700
1701         if (lgr->type == SMC_LGR_SINGLE && !list_empty(&lgr->list)) {
1702                 /* trigger setup of asymm alt link */
1703                 smc_llc_add_link_local(lnk);
1704         }
1705 out:
1706         mutex_unlock(&lgr->llc_conf_mutex);
1707         kfree(qentry);
1708 }
1709
1710 static void smc_llc_delete_link_work(struct work_struct *work)
1711 {
1712         struct smc_link_group *lgr = container_of(work, struct smc_link_group,
1713                                                   llc_del_link_work);
1714
1715         if (list_empty(&lgr->list)) {
1716                 /* link group is terminating */
1717                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1718                 goto out;
1719         }
1720
1721         if (lgr->role == SMC_CLNT)
1722                 smc_llc_process_cli_delete_link(lgr);
1723         else
1724                 smc_llc_process_srv_delete_link(lgr);
1725 out:
1726         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
1727 }
1728
1729 /* process a confirm_rkey request from peer, remote flow */
1730 static void smc_llc_rmt_conf_rkey(struct smc_link_group *lgr)
1731 {
1732         struct smc_llc_msg_confirm_rkey *llc;
1733         struct smc_llc_qentry *qentry;
1734         struct smc_link *link;
1735         int num_entries;
1736         int rk_idx;
1737         int i;
1738
1739         qentry = lgr->llc_flow_rmt.qentry;
1740         llc = &qentry->msg.confirm_rkey;
1741         link = qentry->link;
1742
1743         num_entries = llc->rtoken[0].num_rkeys;
1744         if (num_entries > SMC_LLC_RKEYS_PER_MSG)
1745                 goto out_err;
1746         /* first rkey entry is for receiving link */
1747         rk_idx = smc_rtoken_add(link,
1748                                 llc->rtoken[0].rmb_vaddr,
1749                                 llc->rtoken[0].rmb_key);
1750         if (rk_idx < 0)
1751                 goto out_err;
1752
1753         for (i = 1; i <= min_t(u8, num_entries, SMC_LLC_RKEYS_PER_MSG - 1); i++)
1754                 smc_rtoken_set2(lgr, rk_idx, llc->rtoken[i].link_id,
1755                                 llc->rtoken[i].rmb_vaddr,
1756                                 llc->rtoken[i].rmb_key);
1757         /* max links is 3 so there is no need to support conf_rkey_cont msgs */
1758         goto out;
1759 out_err:
1760         llc->hd.flags |= SMC_LLC_FLAG_RKEY_NEG;
1761         llc->hd.flags |= SMC_LLC_FLAG_RKEY_RETRY;
1762 out:
1763         llc->hd.flags |= SMC_LLC_FLAG_RESP;
1764         smc_llc_init_msg_hdr(&llc->hd, link->lgr, sizeof(*llc));
1765         smc_llc_send_message(link, &qentry->msg);
1766         smc_llc_flow_qentry_del(&lgr->llc_flow_rmt);
1767 }
1768
1769 /* process a delete_rkey request from peer, remote flow */
1770 static void smc_llc_rmt_delete_rkey(struct smc_link_group *lgr)
1771 {
1772         struct smc_llc_msg_delete_rkey *llc;
1773         struct smc_llc_qentry *qentry;
1774         struct smc_link *link;
1775         u8 err_mask = 0;
1776         int i, max;
1777
1778         qentry = lgr->llc_flow_rmt.qentry;
1779         llc = &qentry->msg.delete_rkey;
1780         link = qentry->link;
1781
1782         if (lgr->smc_version == SMC_V2) {
1783                 struct smc_llc_msg_delete_rkey_v2 *llcv2;
1784
1785                 memcpy(lgr->wr_rx_buf_v2, llc, sizeof(*llc));
1786                 llcv2 = (struct smc_llc_msg_delete_rkey_v2 *)lgr->wr_rx_buf_v2;
1787                 llcv2->num_inval_rkeys = 0;
1788
1789                 max = min_t(u8, llcv2->num_rkeys, SMC_LLC_RKEYS_PER_MSG_V2);
1790                 for (i = 0; i < max; i++) {
1791                         if (smc_rtoken_delete(link, llcv2->rkey[i]))
1792                                 llcv2->num_inval_rkeys++;
1793                 }
1794                 memset(&llc->rkey[0], 0, sizeof(llc->rkey));
1795                 memset(&llc->reserved2, 0, sizeof(llc->reserved2));
1796                 smc_llc_init_msg_hdr(&llc->hd, link->lgr, sizeof(*llc));
1797                 if (llcv2->num_inval_rkeys) {
1798                         llc->hd.flags |= SMC_LLC_FLAG_RKEY_NEG;
1799                         llc->err_mask = llcv2->num_inval_rkeys;
1800                 }
1801                 goto finish;
1802         }
1803
1804         max = min_t(u8, llc->num_rkeys, SMC_LLC_DEL_RKEY_MAX);
1805         for (i = 0; i < max; i++) {
1806                 if (smc_rtoken_delete(link, llc->rkey[i]))
1807                         err_mask |= 1 << (SMC_LLC_DEL_RKEY_MAX - 1 - i);
1808         }
1809         if (err_mask) {
1810                 llc->hd.flags |= SMC_LLC_FLAG_RKEY_NEG;
1811                 llc->err_mask = err_mask;
1812         }
1813 finish:
1814         llc->hd.flags |= SMC_LLC_FLAG_RESP;
1815         smc_llc_send_message(link, &qentry->msg);
1816         smc_llc_flow_qentry_del(&lgr->llc_flow_rmt);
1817 }
1818
1819 static void smc_llc_protocol_violation(struct smc_link_group *lgr, u8 type)
1820 {
1821         pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu LLC protocol violation: "
1822                             "llc_type %d\n", SMC_LGR_ID_SIZE, &lgr->id,
1823                             lgr->net->net_cookie, type);
1824         smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_PROT_VIOL);
1825         smc_lgr_terminate_sched(lgr);
1826 }
1827
1828 /* flush the llc event queue */
1829 static void smc_llc_event_flush(struct smc_link_group *lgr)
1830 {
1831         struct smc_llc_qentry *qentry, *q;
1832
1833         spin_lock_bh(&lgr->llc_event_q_lock);
1834         list_for_each_entry_safe(qentry, q, &lgr->llc_event_q, list) {
1835                 list_del_init(&qentry->list);
1836                 kfree(qentry);
1837         }
1838         spin_unlock_bh(&lgr->llc_event_q_lock);
1839 }
1840
1841 static void smc_llc_event_handler(struct smc_llc_qentry *qentry)
1842 {
1843         union smc_llc_msg *llc = &qentry->msg;
1844         struct smc_link *link = qentry->link;
1845         struct smc_link_group *lgr = link->lgr;
1846
1847         if (!smc_link_usable(link))
1848                 goto out;
1849
1850         switch (llc->raw.hdr.common.llc_type) {
1851         case SMC_LLC_TEST_LINK:
1852                 llc->test_link.hd.flags |= SMC_LLC_FLAG_RESP;
1853                 smc_llc_send_message(link, llc);
1854                 break;
1855         case SMC_LLC_ADD_LINK:
1856                 if (list_empty(&lgr->list))
1857                         goto out;       /* lgr is terminating */
1858                 if (lgr->role == SMC_CLNT) {
1859                         if (smc_llc_is_local_add_link(llc)) {
1860                                 if (lgr->llc_flow_lcl.type ==
1861                                     SMC_LLC_FLOW_ADD_LINK)
1862                                         break;  /* add_link in progress */
1863                                 if (smc_llc_flow_start(&lgr->llc_flow_lcl,
1864                                                        qentry)) {
1865                                         schedule_work(&lgr->llc_add_link_work);
1866                                 }
1867                                 return;
1868                         }
1869                         if (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_ADD_LINK &&
1870                             !lgr->llc_flow_lcl.qentry) {
1871                                 /* a flow is waiting for this message */
1872                                 smc_llc_flow_qentry_set(&lgr->llc_flow_lcl,
1873                                                         qentry);
1874                                 wake_up(&lgr->llc_msg_waiter);
1875                                 return;
1876                         }
1877                         if (lgr->llc_flow_lcl.type ==
1878                                         SMC_LLC_FLOW_REQ_ADD_LINK) {
1879                                 /* server started add_link processing */
1880                                 lgr->llc_flow_lcl.type = SMC_LLC_FLOW_ADD_LINK;
1881                                 smc_llc_flow_qentry_set(&lgr->llc_flow_lcl,
1882                                                         qentry);
1883                                 schedule_work(&lgr->llc_add_link_work);
1884                                 return;
1885                         }
1886                         if (smc_llc_flow_start(&lgr->llc_flow_lcl, qentry)) {
1887                                 schedule_work(&lgr->llc_add_link_work);
1888                         }
1889                 } else if (smc_llc_flow_start(&lgr->llc_flow_lcl, qentry)) {
1890                         /* as smc server, handle client suggestion */
1891                         schedule_work(&lgr->llc_add_link_work);
1892                 }
1893                 return;
1894         case SMC_LLC_CONFIRM_LINK:
1895         case SMC_LLC_ADD_LINK_CONT:
1896                 if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
1897                         /* a flow is waiting for this message */
1898                         smc_llc_flow_qentry_set(&lgr->llc_flow_lcl, qentry);
1899                         wake_up(&lgr->llc_msg_waiter);
1900                         return;
1901                 }
1902                 break;
1903         case SMC_LLC_DELETE_LINK:
1904                 if (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_ADD_LINK &&
1905                     !lgr->llc_flow_lcl.qentry) {
1906                         /* DEL LINK REQ during ADD LINK SEQ */
1907                         smc_llc_flow_qentry_set(&lgr->llc_flow_lcl, qentry);
1908                         wake_up(&lgr->llc_msg_waiter);
1909                 } else if (smc_llc_flow_start(&lgr->llc_flow_lcl, qentry)) {
1910                         schedule_work(&lgr->llc_del_link_work);
1911                 }
1912                 return;
1913         case SMC_LLC_CONFIRM_RKEY:
1914                 /* new request from remote, assign to remote flow */
1915                 if (smc_llc_flow_start(&lgr->llc_flow_rmt, qentry)) {
1916                         /* process here, does not wait for more llc msgs */
1917                         smc_llc_rmt_conf_rkey(lgr);
1918                         smc_llc_flow_stop(lgr, &lgr->llc_flow_rmt);
1919                 }
1920                 return;
1921         case SMC_LLC_CONFIRM_RKEY_CONT:
1922                 /* not used because max links is 3, and 3 rkeys fit into
1923                  * one CONFIRM_RKEY message
1924                  */
1925                 break;
1926         case SMC_LLC_DELETE_RKEY:
1927                 /* new request from remote, assign to remote flow */
1928                 if (smc_llc_flow_start(&lgr->llc_flow_rmt, qentry)) {
1929                         /* process here, does not wait for more llc msgs */
1930                         smc_llc_rmt_delete_rkey(lgr);
1931                         smc_llc_flow_stop(lgr, &lgr->llc_flow_rmt);
1932                 }
1933                 return;
1934         case SMC_LLC_REQ_ADD_LINK:
1935                 /* handle response here, smc_llc_flow_stop() cannot be called
1936                  * in tasklet context
1937                  */
1938                 if (lgr->role == SMC_CLNT &&
1939                     lgr->llc_flow_lcl.type == SMC_LLC_FLOW_REQ_ADD_LINK &&
1940                     (llc->raw.hdr.flags & SMC_LLC_FLAG_RESP)) {
1941                         smc_llc_flow_stop(link->lgr, &lgr->llc_flow_lcl);
1942                 } else if (lgr->role == SMC_SERV) {
1943                         if (smc_llc_flow_start(&lgr->llc_flow_lcl, qentry)) {
1944                                 /* as smc server, handle client suggestion */
1945                                 lgr->llc_flow_lcl.type = SMC_LLC_FLOW_ADD_LINK;
1946                                 schedule_work(&lgr->llc_add_link_work);
1947                         }
1948                         return;
1949                 }
1950                 break;
1951         default:
1952                 smc_llc_protocol_violation(lgr, llc->raw.hdr.common.type);
1953                 break;
1954         }
1955 out:
1956         kfree(qentry);
1957 }
1958
1959 /* worker to process llc messages on the event queue */
1960 static void smc_llc_event_work(struct work_struct *work)
1961 {
1962         struct smc_link_group *lgr = container_of(work, struct smc_link_group,
1963                                                   llc_event_work);
1964         struct smc_llc_qentry *qentry;
1965
1966         if (!lgr->llc_flow_lcl.type && lgr->delayed_event) {
1967                 qentry = lgr->delayed_event;
1968                 lgr->delayed_event = NULL;
1969                 if (smc_link_usable(qentry->link))
1970                         smc_llc_event_handler(qentry);
1971                 else
1972                         kfree(qentry);
1973         }
1974
1975 again:
1976         spin_lock_bh(&lgr->llc_event_q_lock);
1977         if (!list_empty(&lgr->llc_event_q)) {
1978                 qentry = list_first_entry(&lgr->llc_event_q,
1979                                           struct smc_llc_qentry, list);
1980                 list_del_init(&qentry->list);
1981                 spin_unlock_bh(&lgr->llc_event_q_lock);
1982                 smc_llc_event_handler(qentry);
1983                 goto again;
1984         }
1985         spin_unlock_bh(&lgr->llc_event_q_lock);
1986 }
1987
1988 /* process llc responses in tasklet context */
1989 static void smc_llc_rx_response(struct smc_link *link,
1990                                 struct smc_llc_qentry *qentry)
1991 {
1992         enum smc_llc_flowtype flowtype = link->lgr->llc_flow_lcl.type;
1993         struct smc_llc_flow *flow = &link->lgr->llc_flow_lcl;
1994         u8 llc_type = qentry->msg.raw.hdr.common.llc_type;
1995
1996         switch (llc_type) {
1997         case SMC_LLC_TEST_LINK:
1998                 if (smc_link_active(link))
1999                         complete(&link->llc_testlink_resp);
2000                 break;
2001         case SMC_LLC_ADD_LINK:
2002         case SMC_LLC_ADD_LINK_CONT:
2003         case SMC_LLC_CONFIRM_LINK:
2004                 if (flowtype != SMC_LLC_FLOW_ADD_LINK || flow->qentry)
2005                         break;  /* drop out-of-flow response */
2006                 goto assign;
2007         case SMC_LLC_DELETE_LINK:
2008                 if (flowtype != SMC_LLC_FLOW_DEL_LINK || flow->qentry)
2009                         break;  /* drop out-of-flow response */
2010                 goto assign;
2011         case SMC_LLC_CONFIRM_RKEY:
2012         case SMC_LLC_DELETE_RKEY:
2013                 if (flowtype != SMC_LLC_FLOW_RKEY || flow->qentry)
2014                         break;  /* drop out-of-flow response */
2015                 goto assign;
2016         case SMC_LLC_CONFIRM_RKEY_CONT:
2017                 /* not used because max links is 3 */
2018                 break;
2019         default:
2020                 smc_llc_protocol_violation(link->lgr,
2021                                            qentry->msg.raw.hdr.common.type);
2022                 break;
2023         }
2024         kfree(qentry);
2025         return;
2026 assign:
2027         /* assign responses to the local flow, we requested them */
2028         smc_llc_flow_qentry_set(&link->lgr->llc_flow_lcl, qentry);
2029         wake_up(&link->lgr->llc_msg_waiter);
2030 }
2031
2032 static void smc_llc_enqueue(struct smc_link *link, union smc_llc_msg *llc)
2033 {
2034         struct smc_link_group *lgr = link->lgr;
2035         struct smc_llc_qentry *qentry;
2036         unsigned long flags;
2037
2038         qentry = kmalloc(sizeof(*qentry), GFP_ATOMIC);
2039         if (!qentry)
2040                 return;
2041         qentry->link = link;
2042         INIT_LIST_HEAD(&qentry->list);
2043         memcpy(&qentry->msg, llc, sizeof(union smc_llc_msg));
2044
2045         /* process responses immediately */
2046         if ((llc->raw.hdr.flags & SMC_LLC_FLAG_RESP) &&
2047             llc->raw.hdr.common.llc_type != SMC_LLC_REQ_ADD_LINK) {
2048                 smc_llc_rx_response(link, qentry);
2049                 return;
2050         }
2051
2052         /* add requests to event queue */
2053         spin_lock_irqsave(&lgr->llc_event_q_lock, flags);
2054         list_add_tail(&qentry->list, &lgr->llc_event_q);
2055         spin_unlock_irqrestore(&lgr->llc_event_q_lock, flags);
2056         queue_work(system_highpri_wq, &lgr->llc_event_work);
2057 }
2058
2059 /* copy received msg and add it to the event queue */
2060 static void smc_llc_rx_handler(struct ib_wc *wc, void *buf)
2061 {
2062         struct smc_link *link = (struct smc_link *)wc->qp->qp_context;
2063         union smc_llc_msg *llc = buf;
2064
2065         if (wc->byte_len < sizeof(*llc))
2066                 return; /* short message */
2067         if (!llc->raw.hdr.common.llc_version) {
2068                 if (llc->raw.hdr.length != sizeof(*llc))
2069                         return; /* invalid message */
2070         } else {
2071                 if (llc->raw.hdr.length_v2 < sizeof(*llc))
2072                         return; /* invalid message */
2073         }
2074
2075         smc_llc_enqueue(link, llc);
2076 }
2077
2078 /***************************** worker, utils *********************************/
2079
2080 static void smc_llc_testlink_work(struct work_struct *work)
2081 {
2082         struct smc_link *link = container_of(to_delayed_work(work),
2083                                              struct smc_link, llc_testlink_wrk);
2084         unsigned long next_interval;
2085         unsigned long expire_time;
2086         u8 user_data[16] = { 0 };
2087         int rc;
2088
2089         if (!smc_link_active(link))
2090                 return;         /* don't reschedule worker */
2091         expire_time = link->wr_rx_tstamp + link->llc_testlink_time;
2092         if (time_is_after_jiffies(expire_time)) {
2093                 next_interval = expire_time - jiffies;
2094                 goto out;
2095         }
2096         reinit_completion(&link->llc_testlink_resp);
2097         smc_llc_send_test_link(link, user_data);
2098         /* receive TEST LINK response over RoCE fabric */
2099         rc = wait_for_completion_interruptible_timeout(&link->llc_testlink_resp,
2100                                                        SMC_LLC_WAIT_TIME);
2101         if (!smc_link_active(link))
2102                 return;         /* link state changed */
2103         if (rc <= 0) {
2104                 smcr_link_down_cond_sched(link);
2105                 return;
2106         }
2107         next_interval = link->llc_testlink_time;
2108 out:
2109         schedule_delayed_work(&link->llc_testlink_wrk, next_interval);
2110 }
2111
2112 void smc_llc_lgr_init(struct smc_link_group *lgr, struct smc_sock *smc)
2113 {
2114         struct net *net = sock_net(smc->clcsock->sk);
2115
2116         INIT_WORK(&lgr->llc_event_work, smc_llc_event_work);
2117         INIT_WORK(&lgr->llc_add_link_work, smc_llc_add_link_work);
2118         INIT_WORK(&lgr->llc_del_link_work, smc_llc_delete_link_work);
2119         INIT_LIST_HEAD(&lgr->llc_event_q);
2120         spin_lock_init(&lgr->llc_event_q_lock);
2121         spin_lock_init(&lgr->llc_flow_lock);
2122         init_waitqueue_head(&lgr->llc_flow_waiter);
2123         init_waitqueue_head(&lgr->llc_msg_waiter);
2124         mutex_init(&lgr->llc_conf_mutex);
2125         lgr->llc_testlink_time = net->ipv4.sysctl_tcp_keepalive_time;
2126 }
2127
2128 /* called after lgr was removed from lgr_list */
2129 void smc_llc_lgr_clear(struct smc_link_group *lgr)
2130 {
2131         smc_llc_event_flush(lgr);
2132         wake_up_all(&lgr->llc_flow_waiter);
2133         wake_up_all(&lgr->llc_msg_waiter);
2134         cancel_work_sync(&lgr->llc_event_work);
2135         cancel_work_sync(&lgr->llc_add_link_work);
2136         cancel_work_sync(&lgr->llc_del_link_work);
2137         if (lgr->delayed_event) {
2138                 kfree(lgr->delayed_event);
2139                 lgr->delayed_event = NULL;
2140         }
2141 }
2142
2143 int smc_llc_link_init(struct smc_link *link)
2144 {
2145         init_completion(&link->llc_testlink_resp);
2146         INIT_DELAYED_WORK(&link->llc_testlink_wrk, smc_llc_testlink_work);
2147         return 0;
2148 }
2149
2150 void smc_llc_link_active(struct smc_link *link)
2151 {
2152         pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu link added: id %*phN, "
2153                             "peerid %*phN, ibdev %s, ibport %d\n",
2154                             SMC_LGR_ID_SIZE, &link->lgr->id,
2155                             link->lgr->net->net_cookie,
2156                             SMC_LGR_ID_SIZE, &link->link_uid,
2157                             SMC_LGR_ID_SIZE, &link->peer_link_uid,
2158                             link->smcibdev->ibdev->name, link->ibport);
2159         link->state = SMC_LNK_ACTIVE;
2160         if (link->lgr->llc_testlink_time) {
2161                 link->llc_testlink_time = link->lgr->llc_testlink_time;
2162                 schedule_delayed_work(&link->llc_testlink_wrk,
2163                                       link->llc_testlink_time);
2164         }
2165 }
2166
2167 /* called in worker context */
2168 void smc_llc_link_clear(struct smc_link *link, bool log)
2169 {
2170         if (log)
2171                 pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu link removed: id %*phN"
2172                                     ", peerid %*phN, ibdev %s, ibport %d\n",
2173                                     SMC_LGR_ID_SIZE, &link->lgr->id,
2174                                     link->lgr->net->net_cookie,
2175                                     SMC_LGR_ID_SIZE, &link->link_uid,
2176                                     SMC_LGR_ID_SIZE, &link->peer_link_uid,
2177                                     link->smcibdev->ibdev->name, link->ibport);
2178         complete(&link->llc_testlink_resp);
2179         cancel_delayed_work_sync(&link->llc_testlink_wrk);
2180 }
2181
2182 /* register a new rtoken at the remote peer (for all links) */
2183 int smc_llc_do_confirm_rkey(struct smc_link *send_link,
2184                             struct smc_buf_desc *rmb_desc)
2185 {
2186         struct smc_link_group *lgr = send_link->lgr;
2187         struct smc_llc_qentry *qentry = NULL;
2188         int rc = 0;
2189
2190         rc = smc_llc_send_confirm_rkey(send_link, rmb_desc);
2191         if (rc)
2192                 goto out;
2193         /* receive CONFIRM RKEY response from server over RoCE fabric */
2194         qentry = smc_llc_wait(lgr, send_link, SMC_LLC_WAIT_TIME,
2195                               SMC_LLC_CONFIRM_RKEY);
2196         if (!qentry || (qentry->msg.raw.hdr.flags & SMC_LLC_FLAG_RKEY_NEG))
2197                 rc = -EFAULT;
2198 out:
2199         if (qentry)
2200                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
2201         return rc;
2202 }
2203
2204 /* unregister an rtoken at the remote peer */
2205 int smc_llc_do_delete_rkey(struct smc_link_group *lgr,
2206                            struct smc_buf_desc *rmb_desc)
2207 {
2208         struct smc_llc_qentry *qentry = NULL;
2209         struct smc_link *send_link;
2210         int rc = 0;
2211
2212         send_link = smc_llc_usable_link(lgr);
2213         if (!send_link)
2214                 return -ENOLINK;
2215
2216         /* protected by llc_flow control */
2217         rc = smc_llc_send_delete_rkey(send_link, rmb_desc);
2218         if (rc)
2219                 goto out;
2220         /* receive DELETE RKEY response from server over RoCE fabric */
2221         qentry = smc_llc_wait(lgr, send_link, SMC_LLC_WAIT_TIME,
2222                               SMC_LLC_DELETE_RKEY);
2223         if (!qentry || (qentry->msg.raw.hdr.flags & SMC_LLC_FLAG_RKEY_NEG))
2224                 rc = -EFAULT;
2225 out:
2226         if (qentry)
2227                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
2228         return rc;
2229 }
2230
2231 void smc_llc_link_set_uid(struct smc_link *link)
2232 {
2233         __be32 link_uid;
2234
2235         link_uid = htonl(*((u32 *)link->lgr->id) + link->link_id);
2236         memcpy(link->link_uid, &link_uid, SMC_LGR_ID_SIZE);
2237 }
2238
2239 /* save peers link user id, used for debug purposes */
2240 void smc_llc_save_peer_uid(struct smc_llc_qentry *qentry)
2241 {
2242         memcpy(qentry->link->peer_link_uid, qentry->msg.confirm_link.link_uid,
2243                SMC_LGR_ID_SIZE);
2244 }
2245
2246 /* evaluate confirm link request or response */
2247 int smc_llc_eval_conf_link(struct smc_llc_qentry *qentry,
2248                            enum smc_llc_reqresp type)
2249 {
2250         if (type == SMC_LLC_REQ) {      /* SMC server assigns link_id */
2251                 qentry->link->link_id = qentry->msg.confirm_link.link_num;
2252                 smc_llc_link_set_uid(qentry->link);
2253         }
2254         if (!(qentry->msg.raw.hdr.flags & SMC_LLC_FLAG_NO_RMBE_EYEC))
2255                 return -ENOTSUPP;
2256         return 0;
2257 }
2258
2259 /***************************** init, exit, misc ******************************/
2260
2261 static struct smc_wr_rx_handler smc_llc_rx_handlers[] = {
2262         {
2263                 .handler        = smc_llc_rx_handler,
2264                 .type           = SMC_LLC_CONFIRM_LINK
2265         },
2266         {
2267                 .handler        = smc_llc_rx_handler,
2268                 .type           = SMC_LLC_TEST_LINK
2269         },
2270         {
2271                 .handler        = smc_llc_rx_handler,
2272                 .type           = SMC_LLC_ADD_LINK
2273         },
2274         {
2275                 .handler        = smc_llc_rx_handler,
2276                 .type           = SMC_LLC_ADD_LINK_CONT
2277         },
2278         {
2279                 .handler        = smc_llc_rx_handler,
2280                 .type           = SMC_LLC_DELETE_LINK
2281         },
2282         {
2283                 .handler        = smc_llc_rx_handler,
2284                 .type           = SMC_LLC_CONFIRM_RKEY
2285         },
2286         {
2287                 .handler        = smc_llc_rx_handler,
2288                 .type           = SMC_LLC_CONFIRM_RKEY_CONT
2289         },
2290         {
2291                 .handler        = smc_llc_rx_handler,
2292                 .type           = SMC_LLC_DELETE_RKEY
2293         },
2294         /* V2 types */
2295         {
2296                 .handler        = smc_llc_rx_handler,
2297                 .type           = SMC_LLC_CONFIRM_LINK_V2
2298         },
2299         {
2300                 .handler        = smc_llc_rx_handler,
2301                 .type           = SMC_LLC_TEST_LINK_V2
2302         },
2303         {
2304                 .handler        = smc_llc_rx_handler,
2305                 .type           = SMC_LLC_ADD_LINK_V2
2306         },
2307         {
2308                 .handler        = smc_llc_rx_handler,
2309                 .type           = SMC_LLC_DELETE_LINK_V2
2310         },
2311         {
2312                 .handler        = smc_llc_rx_handler,
2313                 .type           = SMC_LLC_REQ_ADD_LINK_V2
2314         },
2315         {
2316                 .handler        = smc_llc_rx_handler,
2317                 .type           = SMC_LLC_CONFIRM_RKEY_V2
2318         },
2319         {
2320                 .handler        = smc_llc_rx_handler,
2321                 .type           = SMC_LLC_DELETE_RKEY_V2
2322         },
2323         {
2324                 .handler        = NULL,
2325         }
2326 };
2327
2328 int __init smc_llc_init(void)
2329 {
2330         struct smc_wr_rx_handler *handler;
2331         int rc = 0;
2332
2333         for (handler = smc_llc_rx_handlers; handler->handler; handler++) {
2334                 INIT_HLIST_NODE(&handler->list);
2335                 rc = smc_wr_rx_register_handler(handler);
2336                 if (rc)
2337                         break;
2338         }
2339         return rc;
2340 }