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 <Klaus.Wacker@de.ibm.com>
  10  *              Ursula Braun <ubraun@linux.vnet.ibm.com>
  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 max_conns;
  56         u8 reserved[8];
  57 };
  58
  59 #define SMC_LLC_FLAG_ADD_LNK_REJ        0x40
  60 #define SMC_LLC_REJ_RSN_NO_ALT_PATH     1
  61
  62 struct smc_llc_msg_add_link {           /* type 0x02 */
  63         struct smc_llc_hdr hd;
  64         u8 sender_mac[ETH_ALEN];
  65         u8 reserved2[2];
  66         u8 sender_gid[SMC_GID_SIZE];
  67         u8 sender_qp_num[3];
  68         u8 link_num;
  69 #if defined(__BIG_ENDIAN_BITFIELD)
  70         u8 reserved3 : 4,
  71            qp_mtu   : 4;
  72 #elif defined(__LITTLE_ENDIAN_BITFIELD)
  73         u8 qp_mtu   : 4,
  74            reserved3 : 4;
  75 #endif
  76         u8 initial_psn[3];
  77         u8 reserved[8];
  78 };
  79
  80 struct smc_llc_msg_add_link_cont_rt {
  81         __be32 rmb_key;
  82         __be32 rmb_key_new;
  83         __be64 rmb_vaddr_new;
  84 };
  85
  86 struct smc_llc_msg_add_link_v2_ext {
  87 #if defined(__BIG_ENDIAN_BITFIELD)
  88         u8 v2_direct : 1,
  89            reserved  : 7;
  90 #elif defined(__LITTLE_ENDIAN_BITFIELD)
  91         u8 reserved  : 7,
  92            v2_direct : 1;
  93 #endif
  94         u8 reserved2;
  95         u8 client_target_gid[SMC_GID_SIZE];
  96         u8 reserved3[8];
  97         u16 num_rkeys;
  98         struct smc_llc_msg_add_link_cont_rt rt[];
  99 } __packed;             /* format defined in
 100                          * IBM Shared Memory Communications Version 2
 101                          * (https://www.ibm.com/support/pages/node/6326337)
 102                          */
 103
 104 struct smc_llc_msg_req_add_link_v2 {
 105         struct smc_llc_hdr hd;
 106         u8 reserved[20];
 107         u8 gid_cnt;
 108         u8 reserved2[3];
 109         u8 gid[][SMC_GID_SIZE];
 110 };
 111
 112 #define SMC_LLC_RKEYS_PER_CONT_MSG      2
 113
 114 struct smc_llc_msg_add_link_cont {      /* type 0x03 */
 115         struct smc_llc_hdr hd;
 116         u8 link_num;
 117         u8 num_rkeys;
 118         u8 reserved2[2];
 119         struct smc_llc_msg_add_link_cont_rt rt[SMC_LLC_RKEYS_PER_CONT_MSG];
 120         u8 reserved[4];
 121 } __packed;                     /* format defined in RFC7609 */
 122
 123 #define SMC_LLC_FLAG_DEL_LINK_ALL       0x40
 124 #define SMC_LLC_FLAG_DEL_LINK_ORDERLY   0x20
 125
 126 struct smc_llc_msg_del_link {           /* type 0x04 */
 127         struct smc_llc_hdr hd;
 128         u8 link_num;
 129         __be32 reason;
 130         u8 reserved[35];
 131 } __packed;                     /* format defined in RFC7609 */
 132
 133 struct smc_llc_msg_test_link {          /* type 0x07 */
 134         struct smc_llc_hdr hd;
 135         u8 user_data[16];
 136         u8 reserved[24];
 137 };
 138
 139 struct smc_rmb_rtoken {
 140         union {
 141                 u8 num_rkeys;   /* first rtoken byte of CONFIRM LINK msg */
 142                                 /* is actually the num of rtokens, first */
 143                                 /* rtoken is always for the current link */
 144                 u8 link_id;     /* link id of the rtoken */
 145         };
 146         __be32 rmb_key;
 147         __be64 rmb_vaddr;
 148 } __packed;                     /* format defined in RFC7609 */
 149
 150 #define SMC_LLC_RKEYS_PER_MSG           3
 151 #define SMC_LLC_RKEYS_PER_MSG_V2        255
 152
 153 struct smc_llc_msg_confirm_rkey {       /* type 0x06 */
 154         struct smc_llc_hdr hd;
 155         struct smc_rmb_rtoken rtoken[SMC_LLC_RKEYS_PER_MSG];
 156         u8 reserved;
 157 };
 158
 159 #define SMC_LLC_DEL_RKEY_MAX    8
 160 #define SMC_LLC_FLAG_RKEY_RETRY 0x10
 161 #define SMC_LLC_FLAG_RKEY_NEG   0x20
 162
 163 struct smc_llc_msg_delete_rkey {        /* type 0x09 */
 164         struct smc_llc_hdr hd;
 165         u8 num_rkeys;
 166         u8 err_mask;
 167         u8 reserved[2];
 168         __be32 rkey[8];
 169         u8 reserved2[4];
 170 };
 171
 172 struct smc_llc_msg_delete_rkey_v2 {     /* type 0x29 */
 173         struct smc_llc_hdr hd;
 174         u8 num_rkeys;
 175         u8 num_inval_rkeys;
 176         u8 reserved[2];
 177         __be32 rkey[];
 178 };
 179
 180 union smc_llc_msg {
 181         struct smc_llc_msg_confirm_link confirm_link;
 182         struct smc_llc_msg_add_link add_link;
 183         struct smc_llc_msg_req_add_link_v2 req_add_link;
 184         struct smc_llc_msg_add_link_cont add_link_cont;
 185         struct smc_llc_msg_del_link delete_link;
 186
 187         struct smc_llc_msg_confirm_rkey confirm_rkey;
 188         struct smc_llc_msg_delete_rkey delete_rkey;
 189
 190         struct smc_llc_msg_test_link test_link;
 191         struct {
 192                 struct smc_llc_hdr hdr;
 193                 u8 data[SMC_LLC_DATA_LEN];
 194         } raw;
 195 };
 196
 197 #define SMC_LLC_FLAG_RESP               0x80
 198
 199 struct smc_llc_qentry {
 200         struct list_head list;
 201         struct smc_link *link;
 202         union smc_llc_msg msg;
 203 };
 204
 205 static void smc_llc_enqueue(struct smc_link *link, union smc_llc_msg *llc);
 206
 207 struct smc_llc_qentry *smc_llc_flow_qentry_clr(struct smc_llc_flow *flow)
 208 {
 209         struct smc_llc_qentry *qentry = flow->qentry;
 210
 211         flow->qentry = NULL;
 212         return qentry;
 213 }
 214
 215 void smc_llc_flow_qentry_del(struct smc_llc_flow *flow)
 216 {
 217         struct smc_llc_qentry *qentry;
 218
 219         if (flow->qentry) {
 220                 qentry = flow->qentry;
 221                 flow->qentry = NULL;
 222                 kfree(qentry);
 223         }
 224 }
 225
 226 static inline void smc_llc_flow_qentry_set(struct smc_llc_flow *flow,
 227                                            struct smc_llc_qentry *qentry)
 228 {
 229         flow->qentry = qentry;
 230 }
 231
 232 static void smc_llc_flow_parallel(struct smc_link_group *lgr, u8 flow_type,
 233                                   struct smc_llc_qentry *qentry)
 234 {
 235         u8 msg_type = qentry->msg.raw.hdr.common.llc_type;
 236
 237         if ((msg_type == SMC_LLC_ADD_LINK || msg_type == SMC_LLC_DELETE_LINK) &&
 238             flow_type != msg_type && !lgr->delayed_event) {
 239                 lgr->delayed_event = qentry;
 240                 return;
 241         }
 242         /* drop parallel or already-in-progress llc requests */
 243         if (flow_type != msg_type)
 244                 pr_warn_once("smc: SMC-R lg %*phN net %llu dropped parallel "
 245                              "LLC msg: msg %d flow %d role %d\n",
 246                              SMC_LGR_ID_SIZE, &lgr->id,
 247                              lgr->net->net_cookie,
 248                              qentry->msg.raw.hdr.common.type,
 249                              flow_type, lgr->role);
 250         kfree(qentry);
 251 }
 252
 253 /* try to start a new llc flow, initiated by an incoming llc msg */
 254 static bool smc_llc_flow_start(struct smc_llc_flow *flow,
 255                                struct smc_llc_qentry *qentry)
 256 {
 257         struct smc_link_group *lgr = qentry->link->lgr;
 258
 259         spin_lock_bh(&lgr->llc_flow_lock);
 260         if (flow->type) {
 261                 /* a flow is already active */
 262                 smc_llc_flow_parallel(lgr, flow->type, qentry);
 263                 spin_unlock_bh(&lgr->llc_flow_lock);
 264                 return false;
 265         }
 266         switch (qentry->msg.raw.hdr.common.llc_type) {
 267         case SMC_LLC_ADD_LINK:
 268                 flow->type = SMC_LLC_FLOW_ADD_LINK;
 269                 break;
 270         case SMC_LLC_DELETE_LINK:
 271                 flow->type = SMC_LLC_FLOW_DEL_LINK;
 272                 break;
 273         case SMC_LLC_CONFIRM_RKEY:
 274         case SMC_LLC_DELETE_RKEY:
 275                 flow->type = SMC_LLC_FLOW_RKEY;
 276                 break;
 277         default:
 278                 flow->type = SMC_LLC_FLOW_NONE;
 279         }
 280         smc_llc_flow_qentry_set(flow, qentry);
 281         spin_unlock_bh(&lgr->llc_flow_lock);
 282         return true;
 283 }
 284
 285 /* start a new local llc flow, wait till current flow finished */
 286 int smc_llc_flow_initiate(struct smc_link_group *lgr,
 287                           enum smc_llc_flowtype type)
 288 {
 289         enum smc_llc_flowtype allowed_remote = SMC_LLC_FLOW_NONE;
 290         int rc;
 291
 292         /* all flows except confirm_rkey and delete_rkey are exclusive,
 293          * confirm/delete rkey flows can run concurrently (local and remote)
 294          */
 295         if (type == SMC_LLC_FLOW_RKEY)
 296                 allowed_remote = SMC_LLC_FLOW_RKEY;
 297 again:
 298         if (list_empty(&lgr->list))
 299                 return -ENODEV;
 300         spin_lock_bh(&lgr->llc_flow_lock);
 301         if (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE &&
 302             (lgr->llc_flow_rmt.type == SMC_LLC_FLOW_NONE ||
 303              lgr->llc_flow_rmt.type == allowed_remote)) {
 304                 lgr->llc_flow_lcl.type = type;
 305                 spin_unlock_bh(&lgr->llc_flow_lock);
 306                 return 0;
 307         }
 308         spin_unlock_bh(&lgr->llc_flow_lock);
 309         rc = wait_event_timeout(lgr->llc_flow_waiter, (list_empty(&lgr->list) ||
 310                                 (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE &&
 311                                  (lgr->llc_flow_rmt.type == SMC_LLC_FLOW_NONE ||
 312                                   lgr->llc_flow_rmt.type == allowed_remote))),
 313                                 SMC_LLC_WAIT_TIME * 10);
 314         if (!rc)
 315                 return -ETIMEDOUT;
 316         goto again;
 317 }
 318
 319 /* finish the current llc flow */
 320 void smc_llc_flow_stop(struct smc_link_group *lgr, struct smc_llc_flow *flow)
 321 {
 322         spin_lock_bh(&lgr->llc_flow_lock);
 323         memset(flow, 0, sizeof(*flow));
 324         flow->type = SMC_LLC_FLOW_NONE;
 325         spin_unlock_bh(&lgr->llc_flow_lock);
 326         if (!list_empty(&lgr->list) && lgr->delayed_event &&
 327             flow == &lgr->llc_flow_lcl)
 328                 schedule_work(&lgr->llc_event_work);
 329         else
 330                 wake_up(&lgr->llc_flow_waiter);
 331 }
 332
 333 /* lnk is optional and used for early wakeup when link goes down, useful in
 334  * cases where we wait for a response on the link after we sent a request
 335  */
 336 struct smc_llc_qentry *smc_llc_wait(struct smc_link_group *lgr,
 337                                     struct smc_link *lnk,
 338                                     int time_out, u8 exp_msg)
 339 {
 340         struct smc_llc_flow *flow = &lgr->llc_flow_lcl;
 341         u8 rcv_msg;
 342
 343         wait_event_timeout(lgr->llc_msg_waiter,
 344                            (flow->qentry ||
 345                             (lnk && !smc_link_usable(lnk)) ||
 346                             list_empty(&lgr->list)),
 347                            time_out);
 348         if (!flow->qentry ||
 349             (lnk && !smc_link_usable(lnk)) || list_empty(&lgr->list)) {
 350                 smc_llc_flow_qentry_del(flow);
 351                 goto out;
 352         }
 353         rcv_msg = flow->qentry->msg.raw.hdr.common.llc_type;
 354         if (exp_msg && rcv_msg != exp_msg) {
 355                 if (exp_msg == SMC_LLC_ADD_LINK &&
 356                     rcv_msg == SMC_LLC_DELETE_LINK) {
 357                         /* flow_start will delay the unexpected msg */
 358                         smc_llc_flow_start(&lgr->llc_flow_lcl,
 359                                            smc_llc_flow_qentry_clr(flow));
 360                         return NULL;
 361                 }
 362                 pr_warn_once("smc: SMC-R lg %*phN net %llu dropped unexpected LLC msg: "
 363                              "msg %d exp %d flow %d role %d flags %x\n",
 364                              SMC_LGR_ID_SIZE, &lgr->id, lgr->net->net_cookie,
 365                              rcv_msg, exp_msg,
 366                              flow->type, lgr->role,
 367                              flow->qentry->msg.raw.hdr.flags);
 368                 smc_llc_flow_qentry_del(flow);
 369         }
 370 out:
 371         return flow->qentry;
 372 }
 373
 374 /********************************** send *************************************/
 375
 376 struct smc_llc_tx_pend {
 377 };
 378
 379 /* handler for send/transmission completion of an LLC msg */
 380 static void smc_llc_tx_handler(struct smc_wr_tx_pend_priv *pend,
 381                                struct smc_link *link,
 382                                enum ib_wc_status wc_status)
 383 {
 384         /* future work: handle wc_status error for recovery and failover */
 385 }
 386
 387 /**
 388  * smc_llc_add_pending_send() - add LLC control message to pending WQE transmits
 389  * @link: Pointer to SMC link used for sending LLC control message.
 390  * @wr_buf: Out variable returning pointer to work request payload buffer.
 391  * @pend: Out variable returning pointer to private pending WR tracking.
 392  *        It's the context the transmit complete handler will get.
 393  *
 394  * Reserves and pre-fills an entry for a pending work request send/tx.
 395  * Used by mid-level smc_llc_send_msg() to prepare for later actual send/tx.
 396  * Can sleep due to smc_get_ctrl_buf (if not in softirq context).
 397  *
 398  * Return: 0 on success, otherwise an error value.
 399  */
 400 static int smc_llc_add_pending_send(struct smc_link *link,
 401                                     struct smc_wr_buf **wr_buf,
 402                                     struct smc_wr_tx_pend_priv **pend)
 403 {
 404         int rc;
 405
 406         rc = smc_wr_tx_get_free_slot(link, smc_llc_tx_handler, wr_buf, NULL,
 407                                      pend);
 408         if (rc < 0)
 409                 return rc;
 410         BUILD_BUG_ON_MSG(
 411                 sizeof(union smc_llc_msg) > SMC_WR_BUF_SIZE,
 412                 "must increase SMC_WR_BUF_SIZE to at least sizeof(struct smc_llc_msg)");
 413         BUILD_BUG_ON_MSG(
 414                 sizeof(union smc_llc_msg) != SMC_WR_TX_SIZE,
 415                 "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()");
 416         BUILD_BUG_ON_MSG(
 417                 sizeof(struct smc_llc_tx_pend) > SMC_WR_TX_PEND_PRIV_SIZE,
 418                 "must increase SMC_WR_TX_PEND_PRIV_SIZE to at least sizeof(struct smc_llc_tx_pend)");
 419         return 0;
 420 }
 421
 422 static int smc_llc_add_pending_send_v2(struct smc_link *link,
 423                                        struct smc_wr_v2_buf **wr_buf,
 424                                        struct smc_wr_tx_pend_priv **pend)
 425 {
 426         int rc;
 427
 428         rc = smc_wr_tx_get_v2_slot(link, smc_llc_tx_handler, wr_buf, pend);
 429         if (rc < 0)
 430                 return rc;
 431         return 0;
 432 }
 433
 434 static void smc_llc_init_msg_hdr(struct smc_llc_hdr *hdr,
 435                                  struct smc_link_group *lgr, size_t len)
 436 {
 437         if (lgr->smc_version == SMC_V2) {
 438                 hdr->common.llc_version = SMC_V2;
 439                 hdr->length_v2 = len;
 440         } else {
 441                 hdr->common.llc_version = 0;
 442                 hdr->length = len;
 443         }
 444 }
 445
 446 /* high-level API to send LLC confirm link */
 447 int smc_llc_send_confirm_link(struct smc_link *link,
 448                               enum smc_llc_reqresp reqresp)
 449 {
 450         struct smc_llc_msg_confirm_link *confllc;
 451         struct smc_wr_tx_pend_priv *pend;
 452         struct smc_wr_buf *wr_buf;
 453         int rc;
 454
 455         if (!smc_wr_tx_link_hold(link))
 456                 return -ENOLINK;
 457         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 458         if (rc)
 459                 goto put_out;
 460         confllc = (struct smc_llc_msg_confirm_link *)wr_buf;
 461         memset(confllc, 0, sizeof(*confllc));
 462         confllc->hd.common.llc_type = SMC_LLC_CONFIRM_LINK;
 463         smc_llc_init_msg_hdr(&confllc->hd, link->lgr, sizeof(*confllc));
 464         confllc->hd.flags |= SMC_LLC_FLAG_NO_RMBE_EYEC;
 465         if (reqresp == SMC_LLC_RESP)
 466                 confllc->hd.flags |= SMC_LLC_FLAG_RESP;
 467         memcpy(confllc->sender_mac, link->smcibdev->mac[link->ibport - 1],
 468                ETH_ALEN);
 469         memcpy(confllc->sender_gid, link->gid, SMC_GID_SIZE);
 470         hton24(confllc->sender_qp_num, link->roce_qp->qp_num);
 471         confllc->link_num = link->link_id;
 472         memcpy(confllc->link_uid, link->link_uid, SMC_LGR_ID_SIZE);
 473         confllc->max_links = SMC_LINKS_ADD_LNK_MAX;
 474         if (link->lgr->smc_version == SMC_V2 &&
 475             link->lgr->peer_smc_release >= SMC_RELEASE_1) {
 476                 confllc->max_conns = link->lgr->max_conns;
 477                 confllc->max_links = link->lgr->max_links;
 478         }
 479         /* send llc message */
 480         rc = smc_wr_tx_send(link, pend);
 481 put_out:
 482         smc_wr_tx_link_put(link);
 483         return rc;
 484 }
 485
 486 /* send LLC confirm rkey request */
 487 static int smc_llc_send_confirm_rkey(struct smc_link *send_link,
 488                                      struct smc_buf_desc *rmb_desc)
 489 {
 490         struct smc_llc_msg_confirm_rkey *rkeyllc;
 491         struct smc_wr_tx_pend_priv *pend;
 492         struct smc_wr_buf *wr_buf;
 493         struct smc_link *link;
 494         int i, rc, rtok_ix;
 495
 496         if (!smc_wr_tx_link_hold(send_link))
 497                 return -ENOLINK;
 498         rc = smc_llc_add_pending_send(send_link, &wr_buf, &pend);
 499         if (rc)
 500                 goto put_out;
 501         rkeyllc = (struct smc_llc_msg_confirm_rkey *)wr_buf;
 502         memset(rkeyllc, 0, sizeof(*rkeyllc));
 503         rkeyllc->hd.common.llc_type = SMC_LLC_CONFIRM_RKEY;
 504         smc_llc_init_msg_hdr(&rkeyllc->hd, send_link->lgr, sizeof(*rkeyllc));
 505
 506         rtok_ix = 1;
 507         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 508                 link = &send_link->lgr->lnk[i];
 509                 if (smc_link_active(link) && link != send_link) {
 510                         rkeyllc->rtoken[rtok_ix].link_id = link->link_id;
 511                         rkeyllc->rtoken[rtok_ix].rmb_key =
 512                                 htonl(rmb_desc->mr[link->link_idx]->rkey);
 513                         rkeyllc->rtoken[rtok_ix].rmb_vaddr = rmb_desc->is_vm ?
 514                                 cpu_to_be64((uintptr_t)rmb_desc->cpu_addr) :
 515                                 cpu_to_be64((u64)sg_dma_address
 516                                             (rmb_desc->sgt[link->link_idx].sgl));
 517                         rtok_ix++;
 518                 }
 519         }
 520         /* rkey of send_link is in rtoken[0] */
 521         rkeyllc->rtoken[0].num_rkeys = rtok_ix - 1;
 522         rkeyllc->rtoken[0].rmb_key =
 523                 htonl(rmb_desc->mr[send_link->link_idx]->rkey);
 524         rkeyllc->rtoken[0].rmb_vaddr = rmb_desc->is_vm ?
 525                 cpu_to_be64((uintptr_t)rmb_desc->cpu_addr) :
 526                 cpu_to_be64((u64)sg_dma_address
 527                             (rmb_desc->sgt[send_link->link_idx].sgl));
 528         /* send llc message */
 529         rc = smc_wr_tx_send(send_link, pend);
 530 put_out:
 531         smc_wr_tx_link_put(send_link);
 532         return rc;
 533 }
 534
 535 /* send LLC delete rkey request */
 536 static int smc_llc_send_delete_rkey(struct smc_link *link,
 537                                     struct smc_buf_desc *rmb_desc)
 538 {
 539         struct smc_llc_msg_delete_rkey *rkeyllc;
 540         struct smc_wr_tx_pend_priv *pend;
 541         struct smc_wr_buf *wr_buf;
 542         int rc;
 543
 544         if (!smc_wr_tx_link_hold(link))
 545                 return -ENOLINK;
 546         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 547         if (rc)
 548                 goto put_out;
 549         rkeyllc = (struct smc_llc_msg_delete_rkey *)wr_buf;
 550         memset(rkeyllc, 0, sizeof(*rkeyllc));
 551         rkeyllc->hd.common.llc_type = SMC_LLC_DELETE_RKEY;
 552         smc_llc_init_msg_hdr(&rkeyllc->hd, link->lgr, sizeof(*rkeyllc));
 553         rkeyllc->num_rkeys = 1;
 554         rkeyllc->rkey[0] = htonl(rmb_desc->mr[link->link_idx]->rkey);
 555         /* send llc message */
 556         rc = smc_wr_tx_send(link, pend);
 557 put_out:
 558         smc_wr_tx_link_put(link);
 559         return rc;
 560 }
 561
 562 /* return first buffer from any of the next buf lists */
 563 static struct smc_buf_desc *_smc_llc_get_next_rmb(struct smc_link_group *lgr,
 564                                                   int *buf_lst)
 565 {
 566         struct smc_buf_desc *buf_pos;
 567
 568         while (*buf_lst < SMC_RMBE_SIZES) {
 569                 buf_pos = list_first_entry_or_null(&lgr->rmbs[*buf_lst],
 570                                                    struct smc_buf_desc, list);
 571                 if (buf_pos)
 572                         return buf_pos;
 573                 (*buf_lst)++;
 574         }
 575         return NULL;
 576 }
 577
 578 /* return next rmb from buffer lists */
 579 static struct smc_buf_desc *smc_llc_get_next_rmb(struct smc_link_group *lgr,
 580                                                  int *buf_lst,
 581                                                  struct smc_buf_desc *buf_pos)
 582 {
 583         struct smc_buf_desc *buf_next;
 584
 585         if (!buf_pos)
 586                 return _smc_llc_get_next_rmb(lgr, buf_lst);
 587
 588         if (list_is_last(&buf_pos->list, &lgr->rmbs[*buf_lst])) {
 589                 (*buf_lst)++;
 590                 return _smc_llc_get_next_rmb(lgr, buf_lst);
 591         }
 592         buf_next = list_next_entry(buf_pos, list);
 593         return buf_next;
 594 }
 595
 596 static struct smc_buf_desc *smc_llc_get_first_rmb(struct smc_link_group *lgr,
 597                                                   int *buf_lst)
 598 {
 599         *buf_lst = 0;
 600         return smc_llc_get_next_rmb(lgr, buf_lst, NULL);
 601 }
 602
 603 static int smc_llc_fill_ext_v2(struct smc_llc_msg_add_link_v2_ext *ext,
 604                                struct smc_link *link, struct smc_link *link_new)
 605 {
 606         struct smc_link_group *lgr = link->lgr;
 607         struct smc_buf_desc *buf_pos;
 608         int prim_lnk_idx, lnk_idx, i;
 609         struct smc_buf_desc *rmb;
 610         int len = sizeof(*ext);
 611         int buf_lst;
 612
 613         ext->v2_direct = !lgr->uses_gateway;
 614         memcpy(ext->client_target_gid, link_new->gid, SMC_GID_SIZE);
 615
 616         prim_lnk_idx = link->link_idx;
 617         lnk_idx = link_new->link_idx;
 618         down_write(&lgr->rmbs_lock);
 619         ext->num_rkeys = lgr->conns_num;
 620         if (!ext->num_rkeys)
 621                 goto out;
 622         buf_pos = smc_llc_get_first_rmb(lgr, &buf_lst);
 623         for (i = 0; i < ext->num_rkeys; i++) {
 624                 while (buf_pos && !(buf_pos)->used)
 625                         buf_pos = smc_llc_get_next_rmb(lgr, &buf_lst, buf_pos);
 626                 if (!buf_pos)
 627                         break;
 628                 rmb = buf_pos;
 629                 ext->rt[i].rmb_key = htonl(rmb->mr[prim_lnk_idx]->rkey);
 630                 ext->rt[i].rmb_key_new = htonl(rmb->mr[lnk_idx]->rkey);
 631                 ext->rt[i].rmb_vaddr_new = rmb->is_vm ?
 632                         cpu_to_be64((uintptr_t)rmb->cpu_addr) :
 633                         cpu_to_be64((u64)sg_dma_address(rmb->sgt[lnk_idx].sgl));
 634                 buf_pos = smc_llc_get_next_rmb(lgr, &buf_lst, buf_pos);
 635         }
 636         len += i * sizeof(ext->rt[0]);
 637 out:
 638         up_write(&lgr->rmbs_lock);
 639         return len;
 640 }
 641
 642 /* send ADD LINK request or response */
 643 int smc_llc_send_add_link(struct smc_link *link, u8 mac[], u8 gid[],
 644                           struct smc_link *link_new,
 645                           enum smc_llc_reqresp reqresp)
 646 {
 647         struct smc_llc_msg_add_link_v2_ext *ext = NULL;
 648         struct smc_llc_msg_add_link *addllc;
 649         struct smc_wr_tx_pend_priv *pend;
 650         int len = sizeof(*addllc);
 651         int rc;
 652
 653         if (!smc_wr_tx_link_hold(link))
 654                 return -ENOLINK;
 655         if (link->lgr->smc_version == SMC_V2) {
 656                 struct smc_wr_v2_buf *wr_buf;
 657
 658                 rc = smc_llc_add_pending_send_v2(link, &wr_buf, &pend);
 659                 if (rc)
 660                         goto put_out;
 661                 addllc = (struct smc_llc_msg_add_link *)wr_buf;
 662                 ext = (struct smc_llc_msg_add_link_v2_ext *)
 663                                                 &wr_buf->raw[sizeof(*addllc)];
 664                 memset(ext, 0, SMC_WR_TX_SIZE);
 665         } else {
 666                 struct smc_wr_buf *wr_buf;
 667
 668                 rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 669                 if (rc)
 670                         goto put_out;
 671                 addllc = (struct smc_llc_msg_add_link *)wr_buf;
 672         }
 673
 674         memset(addllc, 0, sizeof(*addllc));
 675         addllc->hd.common.llc_type = SMC_LLC_ADD_LINK;
 676         if (reqresp == SMC_LLC_RESP)
 677                 addllc->hd.flags |= SMC_LLC_FLAG_RESP;
 678         memcpy(addllc->sender_mac, mac, ETH_ALEN);
 679         memcpy(addllc->sender_gid, gid, SMC_GID_SIZE);
 680         if (link_new) {
 681                 addllc->link_num = link_new->link_id;
 682                 hton24(addllc->sender_qp_num, link_new->roce_qp->qp_num);
 683                 hton24(addllc->initial_psn, link_new->psn_initial);
 684                 if (reqresp == SMC_LLC_REQ)
 685                         addllc->qp_mtu = link_new->path_mtu;
 686                 else
 687                         addllc->qp_mtu = min(link_new->path_mtu,
 688                                              link_new->peer_mtu);
 689         }
 690         if (ext && link_new)
 691                 len += smc_llc_fill_ext_v2(ext, link, link_new);
 692         smc_llc_init_msg_hdr(&addllc->hd, link->lgr, len);
 693         /* send llc message */
 694         if (link->lgr->smc_version == SMC_V2)
 695                 rc = smc_wr_tx_v2_send(link, pend, len);
 696         else
 697                 rc = smc_wr_tx_send(link, pend);
 698 put_out:
 699         smc_wr_tx_link_put(link);
 700         return rc;
 701 }
 702
 703 /* send DELETE LINK request or response */
 704 int smc_llc_send_delete_link(struct smc_link *link, u8 link_del_id,
 705                              enum smc_llc_reqresp reqresp, bool orderly,
 706                              u32 reason)
 707 {
 708         struct smc_llc_msg_del_link *delllc;
 709         struct smc_wr_tx_pend_priv *pend;
 710         struct smc_wr_buf *wr_buf;
 711         int rc;
 712
 713         if (!smc_wr_tx_link_hold(link))
 714                 return -ENOLINK;
 715         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 716         if (rc)
 717                 goto put_out;
 718         delllc = (struct smc_llc_msg_del_link *)wr_buf;
 719
 720         memset(delllc, 0, sizeof(*delllc));
 721         delllc->hd.common.llc_type = SMC_LLC_DELETE_LINK;
 722         smc_llc_init_msg_hdr(&delllc->hd, link->lgr, sizeof(*delllc));
 723         if (reqresp == SMC_LLC_RESP)
 724                 delllc->hd.flags |= SMC_LLC_FLAG_RESP;
 725         if (orderly)
 726                 delllc->hd.flags |= SMC_LLC_FLAG_DEL_LINK_ORDERLY;
 727         if (link_del_id)
 728                 delllc->link_num = link_del_id;
 729         else
 730                 delllc->hd.flags |= SMC_LLC_FLAG_DEL_LINK_ALL;
 731         delllc->reason = htonl(reason);
 732         /* send llc message */
 733         rc = smc_wr_tx_send(link, pend);
 734 put_out:
 735         smc_wr_tx_link_put(link);
 736         return rc;
 737 }
 738
 739 /* send LLC test link request */
 740 static int smc_llc_send_test_link(struct smc_link *link, u8 user_data[16])
 741 {
 742         struct smc_llc_msg_test_link *testllc;
 743         struct smc_wr_tx_pend_priv *pend;
 744         struct smc_wr_buf *wr_buf;
 745         int rc;
 746
 747         if (!smc_wr_tx_link_hold(link))
 748                 return -ENOLINK;
 749         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 750         if (rc)
 751                 goto put_out;
 752         testllc = (struct smc_llc_msg_test_link *)wr_buf;
 753         memset(testllc, 0, sizeof(*testllc));
 754         testllc->hd.common.llc_type = SMC_LLC_TEST_LINK;
 755         smc_llc_init_msg_hdr(&testllc->hd, link->lgr, sizeof(*testllc));
 756         memcpy(testllc->user_data, user_data, sizeof(testllc->user_data));
 757         /* send llc message */
 758         rc = smc_wr_tx_send(link, pend);
 759 put_out:
 760         smc_wr_tx_link_put(link);
 761         return rc;
 762 }
 763
 764 /* schedule an llc send on link, may wait for buffers */
 765 static int smc_llc_send_message(struct smc_link *link, void *llcbuf)
 766 {
 767         struct smc_wr_tx_pend_priv *pend;
 768         struct smc_wr_buf *wr_buf;
 769         int rc;
 770
 771         if (!smc_wr_tx_link_hold(link))
 772                 return -ENOLINK;
 773         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 774         if (rc)
 775                 goto put_out;
 776         memcpy(wr_buf, llcbuf, sizeof(union smc_llc_msg));
 777         rc = smc_wr_tx_send(link, pend);
 778 put_out:
 779         smc_wr_tx_link_put(link);
 780         return rc;
 781 }
 782
 783 /* schedule an llc send on link, may wait for buffers,
 784  * and wait for send completion notification.
 785  * @return 0 on success
 786  */
 787 static int smc_llc_send_message_wait(struct smc_link *link, void *llcbuf)
 788 {
 789         struct smc_wr_tx_pend_priv *pend;
 790         struct smc_wr_buf *wr_buf;
 791         int rc;
 792
 793         if (!smc_wr_tx_link_hold(link))
 794                 return -ENOLINK;
 795         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 796         if (rc)
 797                 goto put_out;
 798         memcpy(wr_buf, llcbuf, sizeof(union smc_llc_msg));
 799         rc = smc_wr_tx_send_wait(link, pend, SMC_LLC_WAIT_TIME);
 800 put_out:
 801         smc_wr_tx_link_put(link);
 802         return rc;
 803 }
 804
 805 /********************************* receive ***********************************/
 806
 807 static int smc_llc_alloc_alt_link(struct smc_link_group *lgr,
 808                                   enum smc_lgr_type lgr_new_t)
 809 {
 810         int i;
 811
 812         if (lgr->type == SMC_LGR_SYMMETRIC ||
 813             (lgr->type != SMC_LGR_SINGLE &&
 814              (lgr_new_t == SMC_LGR_ASYMMETRIC_LOCAL ||
 815               lgr_new_t == SMC_LGR_ASYMMETRIC_PEER)))
 816                 return -EMLINK;
 817
 818         if (lgr_new_t == SMC_LGR_ASYMMETRIC_LOCAL ||
 819             lgr_new_t == SMC_LGR_ASYMMETRIC_PEER) {
 820                 for (i = SMC_LINKS_PER_LGR_MAX - 1; i >= 0; i--)
 821                         if (lgr->lnk[i].state == SMC_LNK_UNUSED)
 822                                 return i;
 823         } else {
 824                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
 825                         if (lgr->lnk[i].state == SMC_LNK_UNUSED)
 826                                 return i;
 827         }
 828         return -EMLINK;
 829 }
 830
 831 /* send one add_link_continue msg */
 832 static int smc_llc_add_link_cont(struct smc_link *link,
 833                                  struct smc_link *link_new, u8 *num_rkeys_todo,
 834                                  int *buf_lst, struct smc_buf_desc **buf_pos)
 835 {
 836         struct smc_llc_msg_add_link_cont *addc_llc;
 837         struct smc_link_group *lgr = link->lgr;
 838         int prim_lnk_idx, lnk_idx, i, rc;
 839         struct smc_wr_tx_pend_priv *pend;
 840         struct smc_wr_buf *wr_buf;
 841         struct smc_buf_desc *rmb;
 842         u8 n;
 843
 844         if (!smc_wr_tx_link_hold(link))
 845                 return -ENOLINK;
 846         rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
 847         if (rc)
 848                 goto put_out;
 849         addc_llc = (struct smc_llc_msg_add_link_cont *)wr_buf;
 850         memset(addc_llc, 0, sizeof(*addc_llc));
 851
 852         prim_lnk_idx = link->link_idx;
 853         lnk_idx = link_new->link_idx;
 854         addc_llc->link_num = link_new->link_id;
 855         addc_llc->num_rkeys = *num_rkeys_todo;
 856         n = *num_rkeys_todo;
 857         for (i = 0; i < min_t(u8, n, SMC_LLC_RKEYS_PER_CONT_MSG); i++) {
 858                 while (*buf_pos && !(*buf_pos)->used)
 859                         *buf_pos = smc_llc_get_next_rmb(lgr, buf_lst, *buf_pos);
 860                 if (!*buf_pos) {
 861                         addc_llc->num_rkeys = addc_llc->num_rkeys -
 862                                               *num_rkeys_todo;
 863                         *num_rkeys_todo = 0;
 864                         break;
 865                 }
 866                 rmb = *buf_pos;
 867
 868                 addc_llc->rt[i].rmb_key = htonl(rmb->mr[prim_lnk_idx]->rkey);
 869                 addc_llc->rt[i].rmb_key_new = htonl(rmb->mr[lnk_idx]->rkey);
 870                 addc_llc->rt[i].rmb_vaddr_new = rmb->is_vm ?
 871                         cpu_to_be64((uintptr_t)rmb->cpu_addr) :
 872                         cpu_to_be64((u64)sg_dma_address(rmb->sgt[lnk_idx].sgl));
 873
 874                 (*num_rkeys_todo)--;
 875                 *buf_pos = smc_llc_get_next_rmb(lgr, buf_lst, *buf_pos);
 876         }
 877         addc_llc->hd.common.llc_type = SMC_LLC_ADD_LINK_CONT;
 878         addc_llc->hd.length = sizeof(struct smc_llc_msg_add_link_cont);
 879         if (lgr->role == SMC_CLNT)
 880                 addc_llc->hd.flags |= SMC_LLC_FLAG_RESP;
 881         rc = smc_wr_tx_send(link, pend);
 882 put_out:
 883         smc_wr_tx_link_put(link);
 884         return rc;
 885 }
 886
 887 static int smc_llc_cli_rkey_exchange(struct smc_link *link,
 888                                      struct smc_link *link_new)
 889 {
 890         struct smc_llc_msg_add_link_cont *addc_llc;
 891         struct smc_link_group *lgr = link->lgr;
 892         u8 max, num_rkeys_send, num_rkeys_recv;
 893         struct smc_llc_qentry *qentry;
 894         struct smc_buf_desc *buf_pos;
 895         int buf_lst;
 896         int rc = 0;
 897         int i;
 898
 899         down_write(&lgr->rmbs_lock);
 900         num_rkeys_send = lgr->conns_num;
 901         buf_pos = smc_llc_get_first_rmb(lgr, &buf_lst);
 902         do {
 903                 qentry = smc_llc_wait(lgr, NULL, SMC_LLC_WAIT_TIME,
 904                                       SMC_LLC_ADD_LINK_CONT);
 905                 if (!qentry) {
 906                         rc = -ETIMEDOUT;
 907                         break;
 908                 }
 909                 addc_llc = &qentry->msg.add_link_cont;
 910                 num_rkeys_recv = addc_llc->num_rkeys;
 911                 max = min_t(u8, num_rkeys_recv, SMC_LLC_RKEYS_PER_CONT_MSG);
 912                 for (i = 0; i < max; i++) {
 913                         smc_rtoken_set(lgr, link->link_idx, link_new->link_idx,
 914                                        addc_llc->rt[i].rmb_key,
 915                                        addc_llc->rt[i].rmb_vaddr_new,
 916                                        addc_llc->rt[i].rmb_key_new);
 917                         num_rkeys_recv--;
 918                 }
 919                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
 920                 rc = smc_llc_add_link_cont(link, link_new, &num_rkeys_send,
 921                                            &buf_lst, &buf_pos);
 922                 if (rc)
 923                         break;
 924         } while (num_rkeys_send || num_rkeys_recv);
 925
 926         up_write(&lgr->rmbs_lock);
 927         return rc;
 928 }
 929
 930 /* prepare and send an add link reject response */
 931 static int smc_llc_cli_add_link_reject(struct smc_llc_qentry *qentry)
 932 {
 933         qentry->msg.raw.hdr.flags |= SMC_LLC_FLAG_RESP;
 934         qentry->msg.raw.hdr.flags |= SMC_LLC_FLAG_ADD_LNK_REJ;
 935         qentry->msg.raw.hdr.add_link_rej_rsn = SMC_LLC_REJ_RSN_NO_ALT_PATH;
 936         smc_llc_init_msg_hdr(&qentry->msg.raw.hdr, qentry->link->lgr,
 937                              sizeof(qentry->msg));
 938         return smc_llc_send_message(qentry->link, &qentry->msg);
 939 }
 940
 941 static int smc_llc_cli_conf_link(struct smc_link *link,
 942                                  struct smc_init_info *ini,
 943                                  struct smc_link *link_new,
 944                                  enum smc_lgr_type lgr_new_t)
 945 {
 946         struct smc_link_group *lgr = link->lgr;
 947         struct smc_llc_qentry *qentry = NULL;
 948         int rc = 0;
 949
 950         /* receive CONFIRM LINK request over RoCE fabric */
 951         qentry = smc_llc_wait(lgr, NULL, SMC_LLC_WAIT_FIRST_TIME, 0);
 952         if (!qentry) {
 953                 rc = smc_llc_send_delete_link(link, link_new->link_id,
 954                                               SMC_LLC_REQ, false,
 955                                               SMC_LLC_DEL_LOST_PATH);
 956                 return -ENOLINK;
 957         }
 958         if (qentry->msg.raw.hdr.common.llc_type != SMC_LLC_CONFIRM_LINK) {
 959                 /* received DELETE_LINK instead */
 960                 qentry->msg.raw.hdr.flags |= SMC_LLC_FLAG_RESP;
 961                 smc_llc_send_message(link, &qentry->msg);
 962                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
 963                 return -ENOLINK;
 964         }
 965         smc_llc_save_peer_uid(qentry);
 966         smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
 967
 968         rc = smc_ib_modify_qp_rts(link_new);
 969         if (rc) {
 970                 smc_llc_send_delete_link(link, link_new->link_id, SMC_LLC_REQ,
 971                                          false, SMC_LLC_DEL_LOST_PATH);
 972                 return -ENOLINK;
 973         }
 974         smc_wr_remember_qp_attr(link_new);
 975
 976         rc = smcr_buf_reg_lgr(link_new);
 977         if (rc) {
 978                 smc_llc_send_delete_link(link, link_new->link_id, SMC_LLC_REQ,
 979                                          false, SMC_LLC_DEL_LOST_PATH);
 980                 return -ENOLINK;
 981         }
 982
 983         /* send CONFIRM LINK response over RoCE fabric */
 984         rc = smc_llc_send_confirm_link(link_new, SMC_LLC_RESP);
 985         if (rc) {
 986                 smc_llc_send_delete_link(link, link_new->link_id, SMC_LLC_REQ,
 987                                          false, SMC_LLC_DEL_LOST_PATH);
 988                 return -ENOLINK;
 989         }
 990         smc_llc_link_active(link_new);
 991         if (lgr_new_t == SMC_LGR_ASYMMETRIC_LOCAL ||
 992             lgr_new_t == SMC_LGR_ASYMMETRIC_PEER)
 993                 smcr_lgr_set_type_asym(lgr, lgr_new_t, link_new->link_idx);
 994         else
 995                 smcr_lgr_set_type(lgr, lgr_new_t);
 996         return 0;
 997 }
 998
 999 static void smc_llc_save_add_link_rkeys(struct smc_link *link,
1000                                         struct smc_link *link_new)
1001 {
1002         struct smc_llc_msg_add_link_v2_ext *ext;
1003         struct smc_link_group *lgr = link->lgr;
1004         int max, i;
1005
1006         ext = (struct smc_llc_msg_add_link_v2_ext *)((u8 *)lgr->wr_rx_buf_v2 +
1007                                                      SMC_WR_TX_SIZE);
1008         max = min_t(u8, ext->num_rkeys, SMC_LLC_RKEYS_PER_MSG_V2);
1009         down_write(&lgr->rmbs_lock);
1010         for (i = 0; i < max; i++) {
1011                 smc_rtoken_set(lgr, link->link_idx, link_new->link_idx,
1012                                ext->rt[i].rmb_key,
1013                                ext->rt[i].rmb_vaddr_new,
1014                                ext->rt[i].rmb_key_new);
1015         }
1016         up_write(&lgr->rmbs_lock);
1017 }
1018
1019 static void smc_llc_save_add_link_info(struct smc_link *link,
1020                                        struct smc_llc_msg_add_link *add_llc)
1021 {
1022         link->peer_qpn = ntoh24(add_llc->sender_qp_num);
1023         memcpy(link->peer_gid, add_llc->sender_gid, SMC_GID_SIZE);
1024         memcpy(link->peer_mac, add_llc->sender_mac, ETH_ALEN);
1025         link->peer_psn = ntoh24(add_llc->initial_psn);
1026         link->peer_mtu = add_llc->qp_mtu;
1027 }
1028
1029 /* as an SMC client, process an add link request */
1030 int smc_llc_cli_add_link(struct smc_link *link, struct smc_llc_qentry *qentry)
1031 {
1032         struct smc_llc_msg_add_link *llc = &qentry->msg.add_link;
1033         enum smc_lgr_type lgr_new_t = SMC_LGR_SYMMETRIC;
1034         struct smc_link_group *lgr = smc_get_lgr(link);
1035         struct smc_init_info *ini = NULL;
1036         struct smc_link *lnk_new = NULL;
1037         int lnk_idx, rc = 0;
1038
1039         if (!llc->qp_mtu)
1040                 goto out_reject;
1041
1042         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1043         if (!ini) {
1044                 rc = -ENOMEM;
1045                 goto out_reject;
1046         }
1047
1048         if (lgr->type == SMC_LGR_SINGLE && lgr->max_links <= 1) {
1049                 rc = 0;
1050                 goto out_reject;
1051         }
1052
1053         ini->vlan_id = lgr->vlan_id;
1054         if (lgr->smc_version == SMC_V2) {
1055                 ini->check_smcrv2 = true;
1056                 ini->smcrv2.saddr = lgr->saddr;
1057                 ini->smcrv2.daddr = smc_ib_gid_to_ipv4(llc->sender_gid);
1058         }
1059         smc_pnet_find_alt_roce(lgr, ini, link->smcibdev);
1060         if (!memcmp(llc->sender_gid, link->peer_gid, SMC_GID_SIZE) &&
1061             (lgr->smc_version == SMC_V2 ||
1062              !memcmp(llc->sender_mac, link->peer_mac, ETH_ALEN))) {
1063                 if (!ini->ib_dev && !ini->smcrv2.ib_dev_v2)
1064                         goto out_reject;
1065                 lgr_new_t = SMC_LGR_ASYMMETRIC_PEER;
1066         }
1067         if (lgr->smc_version == SMC_V2 && !ini->smcrv2.ib_dev_v2) {
1068                 lgr_new_t = SMC_LGR_ASYMMETRIC_LOCAL;
1069                 ini->smcrv2.ib_dev_v2 = link->smcibdev;
1070                 ini->smcrv2.ib_port_v2 = link->ibport;
1071         } else if (lgr->smc_version < SMC_V2 && !ini->ib_dev) {
1072                 lgr_new_t = SMC_LGR_ASYMMETRIC_LOCAL;
1073                 ini->ib_dev = link->smcibdev;
1074                 ini->ib_port = link->ibport;
1075         }
1076         lnk_idx = smc_llc_alloc_alt_link(lgr, lgr_new_t);
1077         if (lnk_idx < 0)
1078                 goto out_reject;
1079         lnk_new = &lgr->lnk[lnk_idx];
1080         rc = smcr_link_init(lgr, lnk_new, lnk_idx, ini);
1081         if (rc)
1082                 goto out_reject;
1083         smc_llc_save_add_link_info(lnk_new, llc);
1084         lnk_new->link_id = llc->link_num;       /* SMC server assigns link id */
1085         smc_llc_link_set_uid(lnk_new);
1086
1087         rc = smc_ib_ready_link(lnk_new);
1088         if (rc)
1089                 goto out_clear_lnk;
1090
1091         rc = smcr_buf_map_lgr(lnk_new);
1092         if (rc)
1093                 goto out_clear_lnk;
1094
1095         rc = smc_llc_send_add_link(link,
1096                                    lnk_new->smcibdev->mac[lnk_new->ibport - 1],
1097                                    lnk_new->gid, lnk_new, SMC_LLC_RESP);
1098         if (rc)
1099                 goto out_clear_lnk;
1100         if (lgr->smc_version == SMC_V2) {
1101                 smc_llc_save_add_link_rkeys(link, lnk_new);
1102         } else {
1103                 rc = smc_llc_cli_rkey_exchange(link, lnk_new);
1104                 if (rc) {
1105                         rc = 0;
1106                         goto out_clear_lnk;
1107                 }
1108         }
1109         rc = smc_llc_cli_conf_link(link, ini, lnk_new, lgr_new_t);
1110         if (!rc)
1111                 goto out;
1112 out_clear_lnk:
1113         lnk_new->state = SMC_LNK_INACTIVE;
1114         smcr_link_clear(lnk_new, false);
1115 out_reject:
1116         smc_llc_cli_add_link_reject(qentry);
1117 out:
1118         kfree(ini);
1119         kfree(qentry);
1120         return rc;
1121 }
1122
1123 static void smc_llc_send_request_add_link(struct smc_link *link)
1124 {
1125         struct smc_llc_msg_req_add_link_v2 *llc;
1126         struct smc_wr_tx_pend_priv *pend;
1127         struct smc_wr_v2_buf *wr_buf;
1128         struct smc_gidlist gidlist;
1129         int rc, len, i;
1130
1131         if (!smc_wr_tx_link_hold(link))
1132                 return;
1133         if (link->lgr->type == SMC_LGR_SYMMETRIC ||
1134             link->lgr->type == SMC_LGR_ASYMMETRIC_PEER)
1135                 goto put_out;
1136
1137         smc_fill_gid_list(link->lgr, &gidlist, link->smcibdev, link->gid);
1138         if (gidlist.len <= 1)
1139                 goto put_out;
1140
1141         rc = smc_llc_add_pending_send_v2(link, &wr_buf, &pend);
1142         if (rc)
1143                 goto put_out;
1144         llc = (struct smc_llc_msg_req_add_link_v2 *)wr_buf;
1145         memset(llc, 0, SMC_WR_TX_SIZE);
1146
1147         llc->hd.common.llc_type = SMC_LLC_REQ_ADD_LINK;
1148         for (i = 0; i < gidlist.len; i++)
1149                 memcpy(llc->gid[i], gidlist.list[i], sizeof(gidlist.list[0]));
1150         llc->gid_cnt = gidlist.len;
1151         len = sizeof(*llc) + (gidlist.len * sizeof(gidlist.list[0]));
1152         smc_llc_init_msg_hdr(&llc->hd, link->lgr, len);
1153         rc = smc_wr_tx_v2_send(link, pend, len);
1154         if (!rc)
1155                 /* set REQ_ADD_LINK flow and wait for response from peer */
1156                 link->lgr->llc_flow_lcl.type = SMC_LLC_FLOW_REQ_ADD_LINK;
1157 put_out:
1158         smc_wr_tx_link_put(link);
1159 }
1160
1161 /* as an SMC client, invite server to start the add_link processing */
1162 static void smc_llc_cli_add_link_invite(struct smc_link *link,
1163                                         struct smc_llc_qentry *qentry)
1164 {
1165         struct smc_link_group *lgr = smc_get_lgr(link);
1166         struct smc_init_info *ini = NULL;
1167
1168         if (lgr->smc_version == SMC_V2) {
1169                 smc_llc_send_request_add_link(link);
1170                 goto out;
1171         }
1172
1173         if (lgr->type == SMC_LGR_SYMMETRIC ||
1174             lgr->type == SMC_LGR_ASYMMETRIC_PEER)
1175                 goto out;
1176
1177         if (lgr->type == SMC_LGR_SINGLE && lgr->max_links <= 1)
1178                 goto out;
1179
1180         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1181         if (!ini)
1182                 goto out;
1183
1184         ini->vlan_id = lgr->vlan_id;
1185         smc_pnet_find_alt_roce(lgr, ini, link->smcibdev);
1186         if (!ini->ib_dev)
1187                 goto out;
1188
1189         smc_llc_send_add_link(link, ini->ib_dev->mac[ini->ib_port - 1],
1190                               ini->ib_gid, NULL, SMC_LLC_REQ);
1191 out:
1192         kfree(ini);
1193         kfree(qentry);
1194 }
1195
1196 static bool smc_llc_is_empty_llc_message(union smc_llc_msg *llc)
1197 {
1198         int i;
1199
1200         for (i = 0; i < ARRAY_SIZE(llc->raw.data); i++)
1201                 if (llc->raw.data[i])
1202                         return false;
1203         return true;
1204 }
1205
1206 static bool smc_llc_is_local_add_link(union smc_llc_msg *llc)
1207 {
1208         if (llc->raw.hdr.common.llc_type == SMC_LLC_ADD_LINK &&
1209             smc_llc_is_empty_llc_message(llc))
1210                 return true;
1211         return false;
1212 }
1213
1214 static void smc_llc_process_cli_add_link(struct smc_link_group *lgr)
1215 {
1216         struct smc_llc_qentry *qentry;
1217
1218         qentry = smc_llc_flow_qentry_clr(&lgr->llc_flow_lcl);
1219
1220         down_write(&lgr->llc_conf_mutex);
1221         if (smc_llc_is_local_add_link(&qentry->msg))
1222                 smc_llc_cli_add_link_invite(qentry->link, qentry);
1223         else
1224                 smc_llc_cli_add_link(qentry->link, qentry);
1225         up_write(&lgr->llc_conf_mutex);
1226 }
1227
1228 static int smc_llc_active_link_count(struct smc_link_group *lgr)
1229 {
1230         int i, link_count = 0;
1231
1232         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1233                 if (!smc_link_active(&lgr->lnk[i]))
1234                         continue;
1235                 link_count++;
1236         }
1237         return link_count;
1238 }
1239
1240 /* find the asymmetric link when 3 links are established  */
1241 static struct smc_link *smc_llc_find_asym_link(struct smc_link_group *lgr)
1242 {
1243         int asym_idx = -ENOENT;
1244         int i, j, k;
1245         bool found;
1246
1247         /* determine asymmetric link */
1248         found = false;
1249         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1250                 for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) {
1251                         if (!smc_link_usable(&lgr->lnk[i]) ||
1252                             !smc_link_usable(&lgr->lnk[j]))
1253                                 continue;
1254                         if (!memcmp(lgr->lnk[i].gid, lgr->lnk[j].gid,
1255                                     SMC_GID_SIZE)) {
1256                                 found = true;   /* asym_lnk is i or j */
1257                                 break;
1258                         }
1259                 }
1260                 if (found)
1261                         break;
1262         }
1263         if (!found)
1264                 goto out; /* no asymmetric link */
1265         for (k = 0; k < SMC_LINKS_PER_LGR_MAX; k++) {
1266                 if (!smc_link_usable(&lgr->lnk[k]))
1267                         continue;
1268                 if (k != i &&
1269                     !memcmp(lgr->lnk[i].peer_gid, lgr->lnk[k].peer_gid,
1270                             SMC_GID_SIZE)) {
1271                         asym_idx = i;
1272                         break;
1273                 }
1274                 if (k != j &&
1275                     !memcmp(lgr->lnk[j].peer_gid, lgr->lnk[k].peer_gid,
1276                             SMC_GID_SIZE)) {
1277                         asym_idx = j;
1278                         break;
1279                 }
1280         }
1281 out:
1282         return (asym_idx < 0) ? NULL : &lgr->lnk[asym_idx];
1283 }
1284
1285 static void smc_llc_delete_asym_link(struct smc_link_group *lgr)
1286 {
1287         struct smc_link *lnk_new = NULL, *lnk_asym;
1288         struct smc_llc_qentry *qentry;
1289         int rc;
1290
1291         lnk_asym = smc_llc_find_asym_link(lgr);
1292         if (!lnk_asym)
1293                 return; /* no asymmetric link */
1294         if (!smc_link_downing(&lnk_asym->state))
1295                 return;
1296         lnk_new = smc_switch_conns(lgr, lnk_asym, false);
1297         smc_wr_tx_wait_no_pending_sends(lnk_asym);
1298         if (!lnk_new)
1299                 goto out_free;
1300         /* change flow type from ADD_LINK into DEL_LINK */
1301         lgr->llc_flow_lcl.type = SMC_LLC_FLOW_DEL_LINK;
1302         rc = smc_llc_send_delete_link(lnk_new, lnk_asym->link_id, SMC_LLC_REQ,
1303                                       true, SMC_LLC_DEL_NO_ASYM_NEEDED);
1304         if (rc) {
1305                 smcr_link_down_cond(lnk_new);
1306                 goto out_free;
1307         }
1308         qentry = smc_llc_wait(lgr, lnk_new, SMC_LLC_WAIT_TIME,
1309                               SMC_LLC_DELETE_LINK);
1310         if (!qentry) {
1311                 smcr_link_down_cond(lnk_new);
1312                 goto out_free;
1313         }
1314         smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1315 out_free:
1316         smcr_link_clear(lnk_asym, true);
1317 }
1318
1319 static int smc_llc_srv_rkey_exchange(struct smc_link *link,
1320                                      struct smc_link *link_new)
1321 {
1322         struct smc_llc_msg_add_link_cont *addc_llc;
1323         struct smc_link_group *lgr = link->lgr;
1324         u8 max, num_rkeys_send, num_rkeys_recv;
1325         struct smc_llc_qentry *qentry = NULL;
1326         struct smc_buf_desc *buf_pos;
1327         int buf_lst;
1328         int rc = 0;
1329         int i;
1330
1331         down_write(&lgr->rmbs_lock);
1332         num_rkeys_send = lgr->conns_num;
1333         buf_pos = smc_llc_get_first_rmb(lgr, &buf_lst);
1334         do {
1335                 smc_llc_add_link_cont(link, link_new, &num_rkeys_send,
1336                                       &buf_lst, &buf_pos);
1337                 qentry = smc_llc_wait(lgr, link, SMC_LLC_WAIT_TIME,
1338                                       SMC_LLC_ADD_LINK_CONT);
1339                 if (!qentry) {
1340                         rc = -ETIMEDOUT;
1341                         goto out;
1342                 }
1343                 addc_llc = &qentry->msg.add_link_cont;
1344                 num_rkeys_recv = addc_llc->num_rkeys;
1345                 max = min_t(u8, num_rkeys_recv, SMC_LLC_RKEYS_PER_CONT_MSG);
1346                 for (i = 0; i < max; i++) {
1347                         smc_rtoken_set(lgr, link->link_idx, link_new->link_idx,
1348                                        addc_llc->rt[i].rmb_key,
1349                                        addc_llc->rt[i].rmb_vaddr_new,
1350                                        addc_llc->rt[i].rmb_key_new);
1351                         num_rkeys_recv--;
1352                 }
1353                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1354         } while (num_rkeys_send || num_rkeys_recv);
1355 out:
1356         up_write(&lgr->rmbs_lock);
1357         return rc;
1358 }
1359
1360 static int smc_llc_srv_conf_link(struct smc_link *link,
1361                                  struct smc_link *link_new,
1362                                  enum smc_lgr_type lgr_new_t)
1363 {
1364         struct smc_link_group *lgr = link->lgr;
1365         struct smc_llc_qentry *qentry = NULL;
1366         int rc;
1367
1368         /* send CONFIRM LINK request over the RoCE fabric */
1369         rc = smc_llc_send_confirm_link(link_new, SMC_LLC_REQ);
1370         if (rc)
1371                 return -ENOLINK;
1372         /* receive CONFIRM LINK response over the RoCE fabric */
1373         qentry = smc_llc_wait(lgr, link, SMC_LLC_WAIT_FIRST_TIME, 0);
1374         if (!qentry ||
1375             qentry->msg.raw.hdr.common.llc_type != SMC_LLC_CONFIRM_LINK) {
1376                 /* send DELETE LINK */
1377                 smc_llc_send_delete_link(link, link_new->link_id, SMC_LLC_REQ,
1378                                          false, SMC_LLC_DEL_LOST_PATH);
1379                 if (qentry)
1380                         smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1381                 return -ENOLINK;
1382         }
1383         smc_llc_save_peer_uid(qentry);
1384         smc_llc_link_active(link_new);
1385         if (lgr_new_t == SMC_LGR_ASYMMETRIC_LOCAL ||
1386             lgr_new_t == SMC_LGR_ASYMMETRIC_PEER)
1387                 smcr_lgr_set_type_asym(lgr, lgr_new_t, link_new->link_idx);
1388         else
1389                 smcr_lgr_set_type(lgr, lgr_new_t);
1390         smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1391         return 0;
1392 }
1393
1394 static void smc_llc_send_req_add_link_response(struct smc_llc_qentry *qentry)
1395 {
1396         qentry->msg.raw.hdr.flags |= SMC_LLC_FLAG_RESP;
1397         smc_llc_init_msg_hdr(&qentry->msg.raw.hdr, qentry->link->lgr,
1398                              sizeof(qentry->msg));
1399         memset(&qentry->msg.raw.data, 0, sizeof(qentry->msg.raw.data));
1400         smc_llc_send_message(qentry->link, &qentry->msg);
1401 }
1402
1403 int smc_llc_srv_add_link(struct smc_link *link,
1404                          struct smc_llc_qentry *req_qentry)
1405 {
1406         enum smc_lgr_type lgr_new_t = SMC_LGR_SYMMETRIC;
1407         struct smc_link_group *lgr = link->lgr;
1408         struct smc_llc_msg_add_link *add_llc;
1409         struct smc_llc_qentry *qentry = NULL;
1410         bool send_req_add_link_resp = false;
1411         struct smc_link *link_new = NULL;
1412         struct smc_init_info *ini = NULL;
1413         int lnk_idx, rc = 0;
1414
1415         if (req_qentry &&
1416             req_qentry->msg.raw.hdr.common.llc_type == SMC_LLC_REQ_ADD_LINK)
1417                 send_req_add_link_resp = true;
1418
1419         ini = kzalloc(sizeof(*ini), GFP_KERNEL);
1420         if (!ini) {
1421                 rc = -ENOMEM;
1422                 goto out;
1423         }
1424
1425         if (lgr->type == SMC_LGR_SINGLE && lgr->max_links <= 1) {
1426                 rc = 0;
1427                 goto out;
1428         }
1429
1430         /* ignore client add link recommendation, start new flow */
1431         ini->vlan_id = lgr->vlan_id;
1432         if (lgr->smc_version == SMC_V2) {
1433                 ini->check_smcrv2 = true;
1434                 ini->smcrv2.saddr = lgr->saddr;
1435                 if (send_req_add_link_resp) {
1436                         struct smc_llc_msg_req_add_link_v2 *req_add =
1437                                 &req_qentry->msg.req_add_link;
1438
1439                         ini->smcrv2.daddr = smc_ib_gid_to_ipv4(req_add->gid[0]);
1440                 }
1441         }
1442         smc_pnet_find_alt_roce(lgr, ini, link->smcibdev);
1443         if (lgr->smc_version == SMC_V2 && !ini->smcrv2.ib_dev_v2) {
1444                 lgr_new_t = SMC_LGR_ASYMMETRIC_LOCAL;
1445                 ini->smcrv2.ib_dev_v2 = link->smcibdev;
1446                 ini->smcrv2.ib_port_v2 = link->ibport;
1447         } else if (lgr->smc_version < SMC_V2 && !ini->ib_dev) {
1448                 lgr_new_t = SMC_LGR_ASYMMETRIC_LOCAL;
1449                 ini->ib_dev = link->smcibdev;
1450                 ini->ib_port = link->ibport;
1451         }
1452         lnk_idx = smc_llc_alloc_alt_link(lgr, lgr_new_t);
1453         if (lnk_idx < 0) {
1454                 rc = 0;
1455                 goto out;
1456         }
1457
1458         rc = smcr_link_init(lgr, &lgr->lnk[lnk_idx], lnk_idx, ini);
1459         if (rc)
1460                 goto out;
1461         link_new = &lgr->lnk[lnk_idx];
1462
1463         rc = smcr_buf_map_lgr(link_new);
1464         if (rc)
1465                 goto out_err;
1466
1467         rc = smc_llc_send_add_link(link,
1468                                    link_new->smcibdev->mac[link_new->ibport-1],
1469                                    link_new->gid, link_new, SMC_LLC_REQ);
1470         if (rc)
1471                 goto out_err;
1472         send_req_add_link_resp = false;
1473         /* receive ADD LINK response over the RoCE fabric */
1474         qentry = smc_llc_wait(lgr, link, SMC_LLC_WAIT_TIME, SMC_LLC_ADD_LINK);
1475         if (!qentry) {
1476                 rc = -ETIMEDOUT;
1477                 goto out_err;
1478         }
1479         add_llc = &qentry->msg.add_link;
1480         if (add_llc->hd.flags & SMC_LLC_FLAG_ADD_LNK_REJ) {
1481                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1482                 rc = -ENOLINK;
1483                 goto out_err;
1484         }
1485         if (lgr->type == SMC_LGR_SINGLE &&
1486             (!memcmp(add_llc->sender_gid, link->peer_gid, SMC_GID_SIZE) &&
1487              (lgr->smc_version == SMC_V2 ||
1488               !memcmp(add_llc->sender_mac, link->peer_mac, ETH_ALEN)))) {
1489                 lgr_new_t = SMC_LGR_ASYMMETRIC_PEER;
1490         }
1491         smc_llc_save_add_link_info(link_new, add_llc);
1492         smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1493
1494         rc = smc_ib_ready_link(link_new);
1495         if (rc)
1496                 goto out_err;
1497         rc = smcr_buf_reg_lgr(link_new);
1498         if (rc)
1499                 goto out_err;
1500         if (lgr->smc_version == SMC_V2) {
1501                 smc_llc_save_add_link_rkeys(link, link_new);
1502         } else {
1503                 rc = smc_llc_srv_rkey_exchange(link, link_new);
1504                 if (rc)
1505                         goto out_err;
1506         }
1507         rc = smc_llc_srv_conf_link(link, link_new, lgr_new_t);
1508         if (rc)
1509                 goto out_err;
1510         kfree(ini);
1511         return 0;
1512 out_err:
1513         if (link_new) {
1514                 link_new->state = SMC_LNK_INACTIVE;
1515                 smcr_link_clear(link_new, false);
1516         }
1517 out:
1518         kfree(ini);
1519         if (send_req_add_link_resp)
1520                 smc_llc_send_req_add_link_response(req_qentry);
1521         return rc;
1522 }
1523
1524 static void smc_llc_process_srv_add_link(struct smc_link_group *lgr)
1525 {
1526         struct smc_link *link = lgr->llc_flow_lcl.qentry->link;
1527         struct smc_llc_qentry *qentry;
1528         int rc;
1529
1530         qentry = smc_llc_flow_qentry_clr(&lgr->llc_flow_lcl);
1531
1532         down_write(&lgr->llc_conf_mutex);
1533         rc = smc_llc_srv_add_link(link, qentry);
1534         if (!rc && lgr->type == SMC_LGR_SYMMETRIC) {
1535                 /* delete any asymmetric link */
1536                 smc_llc_delete_asym_link(lgr);
1537         }
1538         up_write(&lgr->llc_conf_mutex);
1539         kfree(qentry);
1540 }
1541
1542 /* enqueue a local add_link req to trigger a new add_link flow */
1543 void smc_llc_add_link_local(struct smc_link *link)
1544 {
1545         struct smc_llc_msg_add_link add_llc = {};
1546
1547         add_llc.hd.common.llc_type = SMC_LLC_ADD_LINK;
1548         smc_llc_init_msg_hdr(&add_llc.hd, link->lgr, sizeof(add_llc));
1549         /* no dev and port needed */
1550         smc_llc_enqueue(link, (union smc_llc_msg *)&add_llc);
1551 }
1552
1553 /* worker to process an add link message */
1554 static void smc_llc_add_link_work(struct work_struct *work)
1555 {
1556         struct smc_link_group *lgr = container_of(work, struct smc_link_group,
1557                                                   llc_add_link_work);
1558
1559         if (list_empty(&lgr->list)) {
1560                 /* link group is terminating */
1561                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1562                 goto out;
1563         }
1564
1565         if (lgr->role == SMC_CLNT)
1566                 smc_llc_process_cli_add_link(lgr);
1567         else
1568                 smc_llc_process_srv_add_link(lgr);
1569 out:
1570         if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_REQ_ADD_LINK)
1571                 smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
1572 }
1573
1574 /* enqueue a local del_link msg to trigger a new del_link flow,
1575  * called only for role SMC_SERV
1576  */
1577 void smc_llc_srv_delete_link_local(struct smc_link *link, u8 del_link_id)
1578 {
1579         struct smc_llc_msg_del_link del_llc = {};
1580
1581         del_llc.hd.common.llc_type = SMC_LLC_DELETE_LINK;
1582         smc_llc_init_msg_hdr(&del_llc.hd, link->lgr, sizeof(del_llc));
1583         del_llc.link_num = del_link_id;
1584         del_llc.reason = htonl(SMC_LLC_DEL_LOST_PATH);
1585         del_llc.hd.flags |= SMC_LLC_FLAG_DEL_LINK_ORDERLY;
1586         smc_llc_enqueue(link, (union smc_llc_msg *)&del_llc);
1587 }
1588
1589 static void smc_llc_process_cli_delete_link(struct smc_link_group *lgr)
1590 {
1591         struct smc_link *lnk_del = NULL, *lnk_asym, *lnk;
1592         struct smc_llc_msg_del_link *del_llc;
1593         struct smc_llc_qentry *qentry;
1594         int active_links;
1595         int lnk_idx;
1596
1597         qentry = smc_llc_flow_qentry_clr(&lgr->llc_flow_lcl);
1598         lnk = qentry->link;
1599         del_llc = &qentry->msg.delete_link;
1600
1601         if (del_llc->hd.flags & SMC_LLC_FLAG_DEL_LINK_ALL) {
1602                 smc_lgr_terminate_sched(lgr);
1603                 goto out;
1604         }
1605         down_write(&lgr->llc_conf_mutex);
1606         /* delete single link */
1607         for (lnk_idx = 0; lnk_idx < SMC_LINKS_PER_LGR_MAX; lnk_idx++) {
1608                 if (lgr->lnk[lnk_idx].link_id != del_llc->link_num)
1609                         continue;
1610                 lnk_del = &lgr->lnk[lnk_idx];
1611                 break;
1612         }
1613         del_llc->hd.flags |= SMC_LLC_FLAG_RESP;
1614         if (!lnk_del) {
1615                 /* link was not found */
1616                 del_llc->reason = htonl(SMC_LLC_DEL_NOLNK);
1617                 smc_llc_send_message(lnk, &qentry->msg);
1618                 goto out_unlock;
1619         }
1620         lnk_asym = smc_llc_find_asym_link(lgr);
1621
1622         del_llc->reason = 0;
1623         smc_llc_send_message(lnk, &qentry->msg); /* response */
1624
1625         if (smc_link_downing(&lnk_del->state))
1626                 smc_switch_conns(lgr, lnk_del, false);
1627         smcr_link_clear(lnk_del, true);
1628
1629         active_links = smc_llc_active_link_count(lgr);
1630         if (lnk_del == lnk_asym) {
1631                 /* expected deletion of asym link, don't change lgr state */
1632         } else if (active_links == 1) {
1633                 smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
1634         } else if (!active_links) {
1635                 smcr_lgr_set_type(lgr, SMC_LGR_NONE);
1636                 smc_lgr_terminate_sched(lgr);
1637         }
1638 out_unlock:
1639         up_write(&lgr->llc_conf_mutex);
1640 out:
1641         kfree(qentry);
1642 }
1643
1644 /* try to send a DELETE LINK ALL request on any active link,
1645  * waiting for send completion
1646  */
1647 void smc_llc_send_link_delete_all(struct smc_link_group *lgr, bool ord, u32 rsn)
1648 {
1649         struct smc_llc_msg_del_link delllc = {};
1650         int i;
1651
1652         delllc.hd.common.llc_type = SMC_LLC_DELETE_LINK;
1653         smc_llc_init_msg_hdr(&delllc.hd, lgr, sizeof(delllc));
1654         if (ord)
1655                 delllc.hd.flags |= SMC_LLC_FLAG_DEL_LINK_ORDERLY;
1656         delllc.hd.flags |= SMC_LLC_FLAG_DEL_LINK_ALL;
1657         delllc.reason = htonl(rsn);
1658
1659         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1660                 if (!smc_link_sendable(&lgr->lnk[i]))
1661                         continue;
1662                 if (!smc_llc_send_message_wait(&lgr->lnk[i], &delllc))
1663                         break;
1664         }
1665 }
1666
1667 static void smc_llc_process_srv_delete_link(struct smc_link_group *lgr)
1668 {
1669         struct smc_llc_msg_del_link *del_llc;
1670         struct smc_link *lnk, *lnk_del;
1671         struct smc_llc_qentry *qentry;
1672         int active_links;
1673         int i;
1674
1675         down_write(&lgr->llc_conf_mutex);
1676         qentry = smc_llc_flow_qentry_clr(&lgr->llc_flow_lcl);
1677         lnk = qentry->link;
1678         del_llc = &qentry->msg.delete_link;
1679
1680         if (qentry->msg.delete_link.hd.flags & SMC_LLC_FLAG_DEL_LINK_ALL) {
1681                 /* delete entire lgr */
1682                 smc_llc_send_link_delete_all(lgr, true, ntohl(
1683                                               qentry->msg.delete_link.reason));
1684                 smc_lgr_terminate_sched(lgr);
1685                 goto out;
1686         }
1687         /* delete single link */
1688         lnk_del = NULL;
1689         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1690                 if (lgr->lnk[i].link_id == del_llc->link_num) {
1691                         lnk_del = &lgr->lnk[i];
1692                         break;
1693                 }
1694         }
1695         if (!lnk_del)
1696                 goto out; /* asymmetric link already deleted */
1697
1698         if (smc_link_downing(&lnk_del->state)) {
1699                 if (smc_switch_conns(lgr, lnk_del, false))
1700                         smc_wr_tx_wait_no_pending_sends(lnk_del);
1701         }
1702         if (!list_empty(&lgr->list)) {
1703                 /* qentry is either a request from peer (send it back to
1704                  * initiate the DELETE_LINK processing), or a locally
1705                  * enqueued DELETE_LINK request (forward it)
1706                  */
1707                 if (!smc_llc_send_message(lnk, &qentry->msg)) {
1708                         struct smc_llc_qentry *qentry2;
1709
1710                         qentry2 = smc_llc_wait(lgr, lnk, SMC_LLC_WAIT_TIME,
1711                                                SMC_LLC_DELETE_LINK);
1712                         if (qentry2)
1713                                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1714                 }
1715         }
1716         smcr_link_clear(lnk_del, true);
1717
1718         active_links = smc_llc_active_link_count(lgr);
1719         if (active_links == 1) {
1720                 smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
1721         } else if (!active_links) {
1722                 smcr_lgr_set_type(lgr, SMC_LGR_NONE);
1723                 smc_lgr_terminate_sched(lgr);
1724         }
1725
1726         if (lgr->type == SMC_LGR_SINGLE && !list_empty(&lgr->list)) {
1727                 /* trigger setup of asymm alt link */
1728                 smc_llc_add_link_local(lnk);
1729         }
1730 out:
1731         up_write(&lgr->llc_conf_mutex);
1732         kfree(qentry);
1733 }
1734
1735 static void smc_llc_delete_link_work(struct work_struct *work)
1736 {
1737         struct smc_link_group *lgr = container_of(work, struct smc_link_group,
1738                                                   llc_del_link_work);
1739
1740         if (list_empty(&lgr->list)) {
1741                 /* link group is terminating */
1742                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
1743                 goto out;
1744         }
1745
1746         if (lgr->role == SMC_CLNT)
1747                 smc_llc_process_cli_delete_link(lgr);
1748         else
1749                 smc_llc_process_srv_delete_link(lgr);
1750 out:
1751         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
1752 }
1753
1754 /* process a confirm_rkey request from peer, remote flow */
1755 static void smc_llc_rmt_conf_rkey(struct smc_link_group *lgr)
1756 {
1757         struct smc_llc_msg_confirm_rkey *llc;
1758         struct smc_llc_qentry *qentry;
1759         struct smc_link *link;
1760         int num_entries;
1761         int rk_idx;
1762         int i;
1763
1764         qentry = lgr->llc_flow_rmt.qentry;
1765         llc = &qentry->msg.confirm_rkey;
1766         link = qentry->link;
1767
1768         num_entries = llc->rtoken[0].num_rkeys;
1769         if (num_entries > SMC_LLC_RKEYS_PER_MSG)
1770                 goto out_err;
1771         /* first rkey entry is for receiving link */
1772         rk_idx = smc_rtoken_add(link,
1773                                 llc->rtoken[0].rmb_vaddr,
1774                                 llc->rtoken[0].rmb_key);
1775         if (rk_idx < 0)
1776                 goto out_err;
1777
1778         for (i = 1; i <= min_t(u8, num_entries, SMC_LLC_RKEYS_PER_MSG - 1); i++)
1779                 smc_rtoken_set2(lgr, rk_idx, llc->rtoken[i].link_id,
1780                                 llc->rtoken[i].rmb_vaddr,
1781                                 llc->rtoken[i].rmb_key);
1782         /* max links is 3 so there is no need to support conf_rkey_cont msgs */
1783         goto out;
1784 out_err:
1785         llc->hd.flags |= SMC_LLC_FLAG_RKEY_NEG;
1786         llc->hd.flags |= SMC_LLC_FLAG_RKEY_RETRY;
1787 out:
1788         llc->hd.flags |= SMC_LLC_FLAG_RESP;
1789         smc_llc_init_msg_hdr(&llc->hd, link->lgr, sizeof(*llc));
1790         smc_llc_send_message(link, &qentry->msg);
1791         smc_llc_flow_qentry_del(&lgr->llc_flow_rmt);
1792 }
1793
1794 /* process a delete_rkey request from peer, remote flow */
1795 static void smc_llc_rmt_delete_rkey(struct smc_link_group *lgr)
1796 {
1797         struct smc_llc_msg_delete_rkey *llc;
1798         struct smc_llc_qentry *qentry;
1799         struct smc_link *link;
1800         u8 err_mask = 0;
1801         int i, max;
1802
1803         qentry = lgr->llc_flow_rmt.qentry;
1804         llc = &qentry->msg.delete_rkey;
1805         link = qentry->link;
1806
1807         if (lgr->smc_version == SMC_V2) {
1808                 struct smc_llc_msg_delete_rkey_v2 *llcv2;
1809
1810                 memcpy(lgr->wr_rx_buf_v2, llc, sizeof(*llc));
1811                 llcv2 = (struct smc_llc_msg_delete_rkey_v2 *)lgr->wr_rx_buf_v2;
1812                 llcv2->num_inval_rkeys = 0;
1813
1814                 max = min_t(u8, llcv2->num_rkeys, SMC_LLC_RKEYS_PER_MSG_V2);
1815                 for (i = 0; i < max; i++) {
1816                         if (smc_rtoken_delete(link, llcv2->rkey[i]))
1817                                 llcv2->num_inval_rkeys++;
1818                 }
1819                 memset(&llc->rkey[0], 0, sizeof(llc->rkey));
1820                 memset(&llc->reserved2, 0, sizeof(llc->reserved2));
1821                 smc_llc_init_msg_hdr(&llc->hd, link->lgr, sizeof(*llc));
1822                 if (llcv2->num_inval_rkeys) {
1823                         llc->hd.flags |= SMC_LLC_FLAG_RKEY_NEG;
1824                         llc->err_mask = llcv2->num_inval_rkeys;
1825                 }
1826                 goto finish;
1827         }
1828
1829         max = min_t(u8, llc->num_rkeys, SMC_LLC_DEL_RKEY_MAX);
1830         for (i = 0; i < max; i++) {
1831                 if (smc_rtoken_delete(link, llc->rkey[i]))
1832                         err_mask |= 1 << (SMC_LLC_DEL_RKEY_MAX - 1 - i);
1833         }
1834         if (err_mask) {
1835                 llc->hd.flags |= SMC_LLC_FLAG_RKEY_NEG;
1836                 llc->err_mask = err_mask;
1837         }
1838 finish:
1839         llc->hd.flags |= SMC_LLC_FLAG_RESP;
1840         smc_llc_send_message(link, &qentry->msg);
1841         smc_llc_flow_qentry_del(&lgr->llc_flow_rmt);
1842 }
1843
1844 static void smc_llc_protocol_violation(struct smc_link_group *lgr, u8 type)
1845 {
1846         pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu LLC protocol violation: "
1847                             "llc_type %d\n", SMC_LGR_ID_SIZE, &lgr->id,
1848                             lgr->net->net_cookie, type);
1849         smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_PROT_VIOL);
1850         smc_lgr_terminate_sched(lgr);
1851 }
1852
1853 /* flush the llc event queue */
1854 static void smc_llc_event_flush(struct smc_link_group *lgr)
1855 {
1856         struct smc_llc_qentry *qentry, *q;
1857
1858         spin_lock_bh(&lgr->llc_event_q_lock);
1859         list_for_each_entry_safe(qentry, q, &lgr->llc_event_q, list) {
1860                 list_del_init(&qentry->list);
1861                 kfree(qentry);
1862         }
1863         spin_unlock_bh(&lgr->llc_event_q_lock);
1864 }
1865
1866 static void smc_llc_event_handler(struct smc_llc_qentry *qentry)
1867 {
1868         union smc_llc_msg *llc = &qentry->msg;
1869         struct smc_link *link = qentry->link;
1870         struct smc_link_group *lgr = link->lgr;
1871
1872         if (!smc_link_usable(link))
1873                 goto out;
1874
1875         switch (llc->raw.hdr.common.llc_type) {
1876         case SMC_LLC_TEST_LINK:
1877                 llc->test_link.hd.flags |= SMC_LLC_FLAG_RESP;
1878                 smc_llc_send_message(link, llc);
1879                 break;
1880         case SMC_LLC_ADD_LINK:
1881                 if (list_empty(&lgr->list))
1882                         goto out;       /* lgr is terminating */
1883                 if (lgr->role == SMC_CLNT) {
1884                         if (smc_llc_is_local_add_link(llc)) {
1885                                 if (lgr->llc_flow_lcl.type ==
1886                                     SMC_LLC_FLOW_ADD_LINK)
1887                                         break;  /* add_link in progress */
1888                                 if (smc_llc_flow_start(&lgr->llc_flow_lcl,
1889                                                        qentry)) {
1890                                         schedule_work(&lgr->llc_add_link_work);
1891                                 }
1892                                 return;
1893                         }
1894                         if (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_ADD_LINK &&
1895                             !lgr->llc_flow_lcl.qentry) {
1896                                 /* a flow is waiting for this message */
1897                                 smc_llc_flow_qentry_set(&lgr->llc_flow_lcl,
1898                                                         qentry);
1899                                 wake_up(&lgr->llc_msg_waiter);
1900                                 return;
1901                         }
1902                         if (lgr->llc_flow_lcl.type ==
1903                                         SMC_LLC_FLOW_REQ_ADD_LINK) {
1904                                 /* server started add_link processing */
1905                                 lgr->llc_flow_lcl.type = SMC_LLC_FLOW_ADD_LINK;
1906                                 smc_llc_flow_qentry_set(&lgr->llc_flow_lcl,
1907                                                         qentry);
1908                                 schedule_work(&lgr->llc_add_link_work);
1909                                 return;
1910                         }
1911                         if (smc_llc_flow_start(&lgr->llc_flow_lcl, qentry)) {
1912                                 schedule_work(&lgr->llc_add_link_work);
1913                         }
1914                 } else if (smc_llc_flow_start(&lgr->llc_flow_lcl, qentry)) {
1915                         /* as smc server, handle client suggestion */
1916                         schedule_work(&lgr->llc_add_link_work);
1917                 }
1918                 return;
1919         case SMC_LLC_CONFIRM_LINK:
1920         case SMC_LLC_ADD_LINK_CONT:
1921                 if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
1922                         /* a flow is waiting for this message */
1923                         smc_llc_flow_qentry_set(&lgr->llc_flow_lcl, qentry);
1924                         wake_up(&lgr->llc_msg_waiter);
1925                         return;
1926                 }
1927                 break;
1928         case SMC_LLC_DELETE_LINK:
1929                 if (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_ADD_LINK &&
1930                     !lgr->llc_flow_lcl.qentry) {
1931                         /* DEL LINK REQ during ADD LINK SEQ */
1932                         smc_llc_flow_qentry_set(&lgr->llc_flow_lcl, qentry);
1933                         wake_up(&lgr->llc_msg_waiter);
1934                 } else if (smc_llc_flow_start(&lgr->llc_flow_lcl, qentry)) {
1935                         schedule_work(&lgr->llc_del_link_work);
1936                 }
1937                 return;
1938         case SMC_LLC_CONFIRM_RKEY:
1939                 /* new request from remote, assign to remote flow */
1940                 if (smc_llc_flow_start(&lgr->llc_flow_rmt, qentry)) {
1941                         /* process here, does not wait for more llc msgs */
1942                         smc_llc_rmt_conf_rkey(lgr);
1943                         smc_llc_flow_stop(lgr, &lgr->llc_flow_rmt);
1944                 }
1945                 return;
1946         case SMC_LLC_CONFIRM_RKEY_CONT:
1947                 /* not used because max links is 3, and 3 rkeys fit into
1948                  * one CONFIRM_RKEY message
1949                  */
1950                 break;
1951         case SMC_LLC_DELETE_RKEY:
1952                 /* new request from remote, assign to remote flow */
1953                 if (smc_llc_flow_start(&lgr->llc_flow_rmt, qentry)) {
1954                         /* process here, does not wait for more llc msgs */
1955                         smc_llc_rmt_delete_rkey(lgr);
1956                         smc_llc_flow_stop(lgr, &lgr->llc_flow_rmt);
1957                 }
1958                 return;
1959         case SMC_LLC_REQ_ADD_LINK:
1960                 /* handle response here, smc_llc_flow_stop() cannot be called
1961                  * in tasklet context
1962                  */
1963                 if (lgr->role == SMC_CLNT &&
1964                     lgr->llc_flow_lcl.type == SMC_LLC_FLOW_REQ_ADD_LINK &&
1965                     (llc->raw.hdr.flags & SMC_LLC_FLAG_RESP)) {
1966                         smc_llc_flow_stop(link->lgr, &lgr->llc_flow_lcl);
1967                 } else if (lgr->role == SMC_SERV) {
1968                         if (smc_llc_flow_start(&lgr->llc_flow_lcl, qentry)) {
1969                                 /* as smc server, handle client suggestion */
1970                                 lgr->llc_flow_lcl.type = SMC_LLC_FLOW_ADD_LINK;
1971                                 schedule_work(&lgr->llc_add_link_work);
1972                         }
1973                         return;
1974                 }
1975                 break;
1976         default:
1977                 smc_llc_protocol_violation(lgr, llc->raw.hdr.common.type);
1978                 break;
1979         }
1980 out:
1981         kfree(qentry);
1982 }
1983
1984 /* worker to process llc messages on the event queue */
1985 static void smc_llc_event_work(struct work_struct *work)
1986 {
1987         struct smc_link_group *lgr = container_of(work, struct smc_link_group,
1988                                                   llc_event_work);
1989         struct smc_llc_qentry *qentry;
1990
1991         if (!lgr->llc_flow_lcl.type && lgr->delayed_event) {
1992                 qentry = lgr->delayed_event;
1993                 lgr->delayed_event = NULL;
1994                 if (smc_link_usable(qentry->link))
1995                         smc_llc_event_handler(qentry);
1996                 else
1997                         kfree(qentry);
1998         }
1999
2000 again:
2001         spin_lock_bh(&lgr->llc_event_q_lock);
2002         if (!list_empty(&lgr->llc_event_q)) {
2003                 qentry = list_first_entry(&lgr->llc_event_q,
2004                                           struct smc_llc_qentry, list);
2005                 list_del_init(&qentry->list);
2006                 spin_unlock_bh(&lgr->llc_event_q_lock);
2007                 smc_llc_event_handler(qentry);
2008                 goto again;
2009         }
2010         spin_unlock_bh(&lgr->llc_event_q_lock);
2011 }
2012
2013 /* process llc responses in tasklet context */
2014 static void smc_llc_rx_response(struct smc_link *link,
2015                                 struct smc_llc_qentry *qentry)
2016 {
2017         enum smc_llc_flowtype flowtype = link->lgr->llc_flow_lcl.type;
2018         struct smc_llc_flow *flow = &link->lgr->llc_flow_lcl;
2019         u8 llc_type = qentry->msg.raw.hdr.common.llc_type;
2020
2021         switch (llc_type) {
2022         case SMC_LLC_TEST_LINK:
2023                 if (smc_link_active(link))
2024                         complete(&link->llc_testlink_resp);
2025                 break;
2026         case SMC_LLC_ADD_LINK:
2027         case SMC_LLC_ADD_LINK_CONT:
2028         case SMC_LLC_CONFIRM_LINK:
2029                 if (flowtype != SMC_LLC_FLOW_ADD_LINK || flow->qentry)
2030                         break;  /* drop out-of-flow response */
2031                 goto assign;
2032         case SMC_LLC_DELETE_LINK:
2033                 if (flowtype != SMC_LLC_FLOW_DEL_LINK || flow->qentry)
2034                         break;  /* drop out-of-flow response */
2035                 goto assign;
2036         case SMC_LLC_CONFIRM_RKEY:
2037         case SMC_LLC_DELETE_RKEY:
2038                 if (flowtype != SMC_LLC_FLOW_RKEY || flow->qentry)
2039                         break;  /* drop out-of-flow response */
2040                 goto assign;
2041         case SMC_LLC_CONFIRM_RKEY_CONT:
2042                 /* not used because max links is 3 */
2043                 break;
2044         default:
2045                 smc_llc_protocol_violation(link->lgr,
2046                                            qentry->msg.raw.hdr.common.type);
2047                 break;
2048         }
2049         kfree(qentry);
2050         return;
2051 assign:
2052         /* assign responses to the local flow, we requested them */
2053         smc_llc_flow_qentry_set(&link->lgr->llc_flow_lcl, qentry);
2054         wake_up(&link->lgr->llc_msg_waiter);
2055 }
2056
2057 static void smc_llc_enqueue(struct smc_link *link, union smc_llc_msg *llc)
2058 {
2059         struct smc_link_group *lgr = link->lgr;
2060         struct smc_llc_qentry *qentry;
2061         unsigned long flags;
2062
2063         qentry = kmalloc(sizeof(*qentry), GFP_ATOMIC);
2064         if (!qentry)
2065                 return;
2066         qentry->link = link;
2067         INIT_LIST_HEAD(&qentry->list);
2068         memcpy(&qentry->msg, llc, sizeof(union smc_llc_msg));
2069
2070         /* process responses immediately */
2071         if ((llc->raw.hdr.flags & SMC_LLC_FLAG_RESP) &&
2072             llc->raw.hdr.common.llc_type != SMC_LLC_REQ_ADD_LINK) {
2073                 smc_llc_rx_response(link, qentry);
2074                 return;
2075         }
2076
2077         /* add requests to event queue */
2078         spin_lock_irqsave(&lgr->llc_event_q_lock, flags);
2079         list_add_tail(&qentry->list, &lgr->llc_event_q);
2080         spin_unlock_irqrestore(&lgr->llc_event_q_lock, flags);
2081         queue_work(system_highpri_wq, &lgr->llc_event_work);
2082 }
2083
2084 /* copy received msg and add it to the event queue */
2085 static void smc_llc_rx_handler(struct ib_wc *wc, void *buf)
2086 {
2087         struct smc_link *link = (struct smc_link *)wc->qp->qp_context;
2088         union smc_llc_msg *llc = buf;
2089
2090         if (wc->byte_len < sizeof(*llc))
2091                 return; /* short message */
2092         if (!llc->raw.hdr.common.llc_version) {
2093                 if (llc->raw.hdr.length != sizeof(*llc))
2094                         return; /* invalid message */
2095         } else {
2096                 if (llc->raw.hdr.length_v2 < sizeof(*llc))
2097                         return; /* invalid message */
2098         }
2099
2100         smc_llc_enqueue(link, llc);
2101 }
2102
2103 /***************************** worker, utils *********************************/
2104
2105 static void smc_llc_testlink_work(struct work_struct *work)
2106 {
2107         struct smc_link *link = container_of(to_delayed_work(work),
2108                                              struct smc_link, llc_testlink_wrk);
2109         unsigned long next_interval;
2110         unsigned long expire_time;
2111         u8 user_data[16] = { 0 };
2112         int rc;
2113
2114         if (!smc_link_active(link))
2115                 return;         /* don't reschedule worker */
2116         expire_time = link->wr_rx_tstamp + link->llc_testlink_time;
2117         if (time_is_after_jiffies(expire_time)) {
2118                 next_interval = expire_time - jiffies;
2119                 goto out;
2120         }
2121         reinit_completion(&link->llc_testlink_resp);
2122         smc_llc_send_test_link(link, user_data);
2123         /* receive TEST LINK response over RoCE fabric */
2124         rc = wait_for_completion_interruptible_timeout(&link->llc_testlink_resp,
2125                                                        SMC_LLC_WAIT_TIME);
2126         if (!smc_link_active(link))
2127                 return;         /* link state changed */
2128         if (rc <= 0) {
2129                 smcr_link_down_cond_sched(link);
2130                 return;
2131         }
2132         next_interval = link->llc_testlink_time;
2133 out:
2134         schedule_delayed_work(&link->llc_testlink_wrk, next_interval);
2135 }
2136
2137 void smc_llc_lgr_init(struct smc_link_group *lgr, struct smc_sock *smc)
2138 {
2139         struct net *net = sock_net(smc->clcsock->sk);
2140
2141         INIT_WORK(&lgr->llc_event_work, smc_llc_event_work);
2142         INIT_WORK(&lgr->llc_add_link_work, smc_llc_add_link_work);
2143         INIT_WORK(&lgr->llc_del_link_work, smc_llc_delete_link_work);
2144         INIT_LIST_HEAD(&lgr->llc_event_q);
2145         spin_lock_init(&lgr->llc_event_q_lock);
2146         spin_lock_init(&lgr->llc_flow_lock);
2147         init_waitqueue_head(&lgr->llc_flow_waiter);
2148         init_waitqueue_head(&lgr->llc_msg_waiter);
2149         init_rwsem(&lgr->llc_conf_mutex);
2150         lgr->llc_testlink_time = READ_ONCE(net->smc.sysctl_smcr_testlink_time);
2151 }
2152
2153 /* called after lgr was removed from lgr_list */
2154 void smc_llc_lgr_clear(struct smc_link_group *lgr)
2155 {
2156         smc_llc_event_flush(lgr);
2157         wake_up_all(&lgr->llc_flow_waiter);
2158         wake_up_all(&lgr->llc_msg_waiter);
2159         cancel_work_sync(&lgr->llc_event_work);
2160         cancel_work_sync(&lgr->llc_add_link_work);
2161         cancel_work_sync(&lgr->llc_del_link_work);
2162         if (lgr->delayed_event) {
2163                 kfree(lgr->delayed_event);
2164                 lgr->delayed_event = NULL;
2165         }
2166 }
2167
2168 int smc_llc_link_init(struct smc_link *link)
2169 {
2170         init_completion(&link->llc_testlink_resp);
2171         INIT_DELAYED_WORK(&link->llc_testlink_wrk, smc_llc_testlink_work);
2172         return 0;
2173 }
2174
2175 void smc_llc_link_active(struct smc_link *link)
2176 {
2177         pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu link added: id %*phN, "
2178                             "peerid %*phN, ibdev %s, ibport %d\n",
2179                             SMC_LGR_ID_SIZE, &link->lgr->id,
2180                             link->lgr->net->net_cookie,
2181                             SMC_LGR_ID_SIZE, &link->link_uid,
2182                             SMC_LGR_ID_SIZE, &link->peer_link_uid,
2183                             link->smcibdev->ibdev->name, link->ibport);
2184         link->state = SMC_LNK_ACTIVE;
2185         if (link->lgr->llc_testlink_time) {
2186                 link->llc_testlink_time = link->lgr->llc_testlink_time;
2187                 schedule_delayed_work(&link->llc_testlink_wrk,
2188                                       link->llc_testlink_time);
2189         }
2190 }
2191
2192 /* called in worker context */
2193 void smc_llc_link_clear(struct smc_link *link, bool log)
2194 {
2195         if (log)
2196                 pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu link removed: id %*phN"
2197                                     ", peerid %*phN, ibdev %s, ibport %d\n",
2198                                     SMC_LGR_ID_SIZE, &link->lgr->id,
2199                                     link->lgr->net->net_cookie,
2200                                     SMC_LGR_ID_SIZE, &link->link_uid,
2201                                     SMC_LGR_ID_SIZE, &link->peer_link_uid,
2202                                     link->smcibdev->ibdev->name, link->ibport);
2203         complete(&link->llc_testlink_resp);
2204         cancel_delayed_work_sync(&link->llc_testlink_wrk);
2205 }
2206
2207 /* register a new rtoken at the remote peer (for all links) */
2208 int smc_llc_do_confirm_rkey(struct smc_link *send_link,
2209                             struct smc_buf_desc *rmb_desc)
2210 {
2211         struct smc_link_group *lgr = send_link->lgr;
2212         struct smc_llc_qentry *qentry = NULL;
2213         int rc = 0;
2214
2215         rc = smc_llc_send_confirm_rkey(send_link, rmb_desc);
2216         if (rc)
2217                 goto out;
2218         /* receive CONFIRM RKEY response from server over RoCE fabric */
2219         qentry = smc_llc_wait(lgr, send_link, SMC_LLC_WAIT_TIME,
2220                               SMC_LLC_CONFIRM_RKEY);
2221         if (!qentry || (qentry->msg.raw.hdr.flags & SMC_LLC_FLAG_RKEY_NEG))
2222                 rc = -EFAULT;
2223 out:
2224         if (qentry)
2225                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
2226         return rc;
2227 }
2228
2229 /* unregister an rtoken at the remote peer */
2230 int smc_llc_do_delete_rkey(struct smc_link_group *lgr,
2231                            struct smc_buf_desc *rmb_desc)
2232 {
2233         struct smc_llc_qentry *qentry = NULL;
2234         struct smc_link *send_link;
2235         int rc = 0;
2236
2237         send_link = smc_llc_usable_link(lgr);
2238         if (!send_link)
2239                 return -ENOLINK;
2240
2241         /* protected by llc_flow control */
2242         rc = smc_llc_send_delete_rkey(send_link, rmb_desc);
2243         if (rc)
2244                 goto out;
2245         /* receive DELETE RKEY response from server over RoCE fabric */
2246         qentry = smc_llc_wait(lgr, send_link, SMC_LLC_WAIT_TIME,
2247                               SMC_LLC_DELETE_RKEY);
2248         if (!qentry || (qentry->msg.raw.hdr.flags & SMC_LLC_FLAG_RKEY_NEG))
2249                 rc = -EFAULT;
2250 out:
2251         if (qentry)
2252                 smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
2253         return rc;
2254 }
2255
2256 void smc_llc_link_set_uid(struct smc_link *link)
2257 {
2258         __be32 link_uid;
2259
2260         link_uid = htonl(*((u32 *)link->lgr->id) + link->link_id);
2261         memcpy(link->link_uid, &link_uid, SMC_LGR_ID_SIZE);
2262 }
2263
2264 /* save peers link user id, used for debug purposes */
2265 void smc_llc_save_peer_uid(struct smc_llc_qentry *qentry)
2266 {
2267         memcpy(qentry->link->peer_link_uid, qentry->msg.confirm_link.link_uid,
2268                SMC_LGR_ID_SIZE);
2269 }
2270
2271 /* evaluate confirm link request or response */
2272 int smc_llc_eval_conf_link(struct smc_llc_qentry *qentry,
2273                            enum smc_llc_reqresp type)
2274 {
2275         if (type == SMC_LLC_REQ) {      /* SMC server assigns link_id */
2276                 qentry->link->link_id = qentry->msg.confirm_link.link_num;
2277                 smc_llc_link_set_uid(qentry->link);
2278         }
2279         if (!(qentry->msg.raw.hdr.flags & SMC_LLC_FLAG_NO_RMBE_EYEC))
2280                 return -ENOTSUPP;
2281         return 0;
2282 }
2283
2284 /***************************** init, exit, misc ******************************/
2285
2286 static struct smc_wr_rx_handler smc_llc_rx_handlers[] = {
2287         {
2288                 .handler        = smc_llc_rx_handler,
2289                 .type           = SMC_LLC_CONFIRM_LINK
2290         },
2291         {
2292                 .handler        = smc_llc_rx_handler,
2293                 .type           = SMC_LLC_TEST_LINK
2294         },
2295         {
2296                 .handler        = smc_llc_rx_handler,
2297                 .type           = SMC_LLC_ADD_LINK
2298         },
2299         {
2300                 .handler        = smc_llc_rx_handler,
2301                 .type           = SMC_LLC_ADD_LINK_CONT
2302         },
2303         {
2304                 .handler        = smc_llc_rx_handler,
2305                 .type           = SMC_LLC_DELETE_LINK
2306         },
2307         {
2308                 .handler        = smc_llc_rx_handler,
2309                 .type           = SMC_LLC_CONFIRM_RKEY
2310         },
2311         {
2312                 .handler        = smc_llc_rx_handler,
2313                 .type           = SMC_LLC_CONFIRM_RKEY_CONT
2314         },
2315         {
2316                 .handler        = smc_llc_rx_handler,
2317                 .type           = SMC_LLC_DELETE_RKEY
2318         },
2319         /* V2 types */
2320         {
2321                 .handler        = smc_llc_rx_handler,
2322                 .type           = SMC_LLC_CONFIRM_LINK_V2
2323         },
2324         {
2325                 .handler        = smc_llc_rx_handler,
2326                 .type           = SMC_LLC_TEST_LINK_V2
2327         },
2328         {
2329                 .handler        = smc_llc_rx_handler,
2330                 .type           = SMC_LLC_ADD_LINK_V2
2331         },
2332         {
2333                 .handler        = smc_llc_rx_handler,
2334                 .type           = SMC_LLC_DELETE_LINK_V2
2335         },
2336         {
2337                 .handler        = smc_llc_rx_handler,
2338                 .type           = SMC_LLC_REQ_ADD_LINK_V2
2339         },
2340         {
2341                 .handler        = smc_llc_rx_handler,
2342                 .type           = SMC_LLC_CONFIRM_RKEY_V2
2343         },
2344         {
2345                 .handler        = smc_llc_rx_handler,
2346                 .type           = SMC_LLC_DELETE_RKEY_V2
2347         },
2348         {
2349                 .handler        = NULL,
2350         }
2351 };
2352
2353 int __init smc_llc_init(void)
2354 {
2355         struct smc_wr_rx_handler *handler;
2356         int rc = 0;
2357
2358         for (handler = smc_llc_rx_handlers; handler->handler; handler++) {
2359                 INIT_HLIST_NODE(&handler->list);
2360                 rc = smc_wr_rx_register_handler(handler);
2361                 if (rc)
2362                         break;
2363         }
2364         return rc;
2365 }