linux/net/smc/smc_ib.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *  Shared Memory Communications over RDMA (SMC-R) and RoCE
   4 *
   5 *  IB infrastructure:
   6 *  Establish SMC-R as an Infiniband Client to be notified about added and
   7 *  removed IB devices of type RDMA.
   8 *  Determine device and port characteristics for these IB devices.
   9 *
  10 *  Copyright IBM Corp. 2016
  11 *
  12 *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
  13 */
  14
  15#include <linux/random.h>
  16#include <linux/workqueue.h>
  17#include <linux/scatterlist.h>
  18#include <linux/wait.h>
  19#include <linux/mutex.h>
  20#include <rdma/ib_verbs.h>
  21#include <rdma/ib_cache.h>
  22
  23#include "smc_pnet.h"
  24#include "smc_ib.h"
  25#include "smc_core.h"
  26#include "smc_wr.h"
  27#include "smc.h"
  28#include "smc_netlink.h"
  29
  30#define SMC_MAX_CQE 32766       /* max. # of completion queue elements */
  31
  32#define SMC_QP_MIN_RNR_TIMER            5
  33#define SMC_QP_TIMEOUT                  15 /* 4096 * 2 ** timeout usec */
  34#define SMC_QP_RETRY_CNT                        7 /* 7: infinite */
  35#define SMC_QP_RNR_RETRY                        7 /* 7: infinite */
  36
  37struct smc_ib_devices smc_ib_devices = {        /* smc-registered ib devices */
  38        .mutex = __MUTEX_INITIALIZER(smc_ib_devices.mutex),
  39        .list = LIST_HEAD_INIT(smc_ib_devices.list),
  40};
  41
  42u8 local_systemid[SMC_SYSTEMID_LEN];            /* unique system identifier */
  43
  44static int smc_ib_modify_qp_init(struct smc_link *lnk)
  45{
  46        struct ib_qp_attr qp_attr;
  47
  48        memset(&qp_attr, 0, sizeof(qp_attr));
  49        qp_attr.qp_state = IB_QPS_INIT;
  50        qp_attr.pkey_index = 0;
  51        qp_attr.port_num = lnk->ibport;
  52        qp_attr.qp_access_flags = IB_ACCESS_LOCAL_WRITE
  53                                | IB_ACCESS_REMOTE_WRITE;
  54        return ib_modify_qp(lnk->roce_qp, &qp_attr,
  55                            IB_QP_STATE | IB_QP_PKEY_INDEX |
  56                            IB_QP_ACCESS_FLAGS | IB_QP_PORT);
  57}
  58
  59static int smc_ib_modify_qp_rtr(struct smc_link *lnk)
  60{
  61        enum ib_qp_attr_mask qp_attr_mask =
  62                IB_QP_STATE | IB_QP_AV | IB_QP_PATH_MTU | IB_QP_DEST_QPN |
  63                IB_QP_RQ_PSN | IB_QP_MAX_DEST_RD_ATOMIC | IB_QP_MIN_RNR_TIMER;
  64        struct ib_qp_attr qp_attr;
  65
  66        memset(&qp_attr, 0, sizeof(qp_attr));
  67        qp_attr.qp_state = IB_QPS_RTR;
  68        qp_attr.path_mtu = min(lnk->path_mtu, lnk->peer_mtu);
  69        qp_attr.ah_attr.type = RDMA_AH_ATTR_TYPE_ROCE;
  70        rdma_ah_set_port_num(&qp_attr.ah_attr, lnk->ibport);
  71        rdma_ah_set_grh(&qp_attr.ah_attr, NULL, 0, lnk->sgid_index, 1, 0);
  72        rdma_ah_set_dgid_raw(&qp_attr.ah_attr, lnk->peer_gid);
  73        memcpy(&qp_attr.ah_attr.roce.dmac, lnk->peer_mac,
  74               sizeof(lnk->peer_mac));
  75        qp_attr.dest_qp_num = lnk->peer_qpn;
  76        qp_attr.rq_psn = lnk->peer_psn; /* starting receive packet seq # */
  77        qp_attr.max_dest_rd_atomic = 1; /* max # of resources for incoming
  78                                         * requests
  79                                         */
  80        qp_attr.min_rnr_timer = SMC_QP_MIN_RNR_TIMER;
  81
  82        return ib_modify_qp(lnk->roce_qp, &qp_attr, qp_attr_mask);
  83}
  84
  85int smc_ib_modify_qp_rts(struct smc_link *lnk)
  86{
  87        struct ib_qp_attr qp_attr;
  88
  89        memset(&qp_attr, 0, sizeof(qp_attr));
  90        qp_attr.qp_state = IB_QPS_RTS;
  91        qp_attr.timeout = SMC_QP_TIMEOUT;       /* local ack timeout */
  92        qp_attr.retry_cnt = SMC_QP_RETRY_CNT;   /* retry count */
  93        qp_attr.rnr_retry = SMC_QP_RNR_RETRY;   /* RNR retries, 7=infinite */
  94        qp_attr.sq_psn = lnk->psn_initial;      /* starting send packet seq # */
  95        qp_attr.max_rd_atomic = 1;      /* # of outstanding RDMA reads and
  96                                         * atomic ops allowed
  97                                         */
  98        return ib_modify_qp(lnk->roce_qp, &qp_attr,
  99                            IB_QP_STATE | IB_QP_TIMEOUT | IB_QP_RETRY_CNT |
 100                            IB_QP_SQ_PSN | IB_QP_RNR_RETRY |
 101                            IB_QP_MAX_QP_RD_ATOMIC);
 102}
 103
 104int smc_ib_modify_qp_reset(struct smc_link *lnk)
 105{
 106        struct ib_qp_attr qp_attr;
 107
 108        memset(&qp_attr, 0, sizeof(qp_attr));
 109        qp_attr.qp_state = IB_QPS_RESET;
 110        return ib_modify_qp(lnk->roce_qp, &qp_attr, IB_QP_STATE);
 111}
 112
 113int smc_ib_ready_link(struct smc_link *lnk)
 114{
 115        struct smc_link_group *lgr = smc_get_lgr(lnk);
 116        int rc = 0;
 117
 118        rc = smc_ib_modify_qp_init(lnk);
 119        if (rc)
 120                goto out;
 121
 122        rc = smc_ib_modify_qp_rtr(lnk);
 123        if (rc)
 124                goto out;
 125        smc_wr_remember_qp_attr(lnk);
 126        rc = ib_req_notify_cq(lnk->smcibdev->roce_cq_recv,
 127                              IB_CQ_SOLICITED_MASK);
 128        if (rc)
 129                goto out;
 130        rc = smc_wr_rx_post_init(lnk);
 131        if (rc)
 132                goto out;
 133        smc_wr_remember_qp_attr(lnk);
 134
 135        if (lgr->role == SMC_SERV) {
 136                rc = smc_ib_modify_qp_rts(lnk);
 137                if (rc)
 138                        goto out;
 139                smc_wr_remember_qp_attr(lnk);
 140        }
 141out:
 142        return rc;
 143}
 144
 145static int smc_ib_fill_mac(struct smc_ib_device *smcibdev, u8 ibport)
 146{
 147        const struct ib_gid_attr *attr;
 148        int rc;
 149
 150        attr = rdma_get_gid_attr(smcibdev->ibdev, ibport, 0);
 151        if (IS_ERR(attr))
 152                return -ENODEV;
 153
 154        rc = rdma_read_gid_l2_fields(attr, NULL, smcibdev->mac[ibport - 1]);
 155        rdma_put_gid_attr(attr);
 156        return rc;
 157}
 158
 159/* Create an identifier unique for this instance of SMC-R.
 160 * The MAC-address of the first active registered IB device
 161 * plus a random 2-byte number is used to create this identifier.
 162 * This name is delivered to the peer during connection initialization.
 163 */
 164static inline void smc_ib_define_local_systemid(struct smc_ib_device *smcibdev,
 165                                                u8 ibport)
 166{
 167        memcpy(&local_systemid[2], &smcibdev->mac[ibport - 1],
 168               sizeof(smcibdev->mac[ibport - 1]));
 169}
 170
 171bool smc_ib_is_valid_local_systemid(void)
 172{
 173        return !is_zero_ether_addr(&local_systemid[2]);
 174}
 175
 176static void smc_ib_init_local_systemid(void)
 177{
 178        get_random_bytes(&local_systemid[0], 2);
 179}
 180
 181bool smc_ib_port_active(struct smc_ib_device *smcibdev, u8 ibport)
 182{
 183        return smcibdev->pattr[ibport - 1].state == IB_PORT_ACTIVE;
 184}
 185
 186/* determine the gid for an ib-device port and vlan id */
 187int smc_ib_determine_gid(struct smc_ib_device *smcibdev, u8 ibport,
 188                         unsigned short vlan_id, u8 gid[], u8 *sgid_index)
 189{
 190        const struct ib_gid_attr *attr;
 191        const struct net_device *ndev;
 192        int i;
 193
 194        for (i = 0; i < smcibdev->pattr[ibport - 1].gid_tbl_len; i++) {
 195                attr = rdma_get_gid_attr(smcibdev->ibdev, ibport, i);
 196                if (IS_ERR(attr))
 197                        continue;
 198
 199                rcu_read_lock();
 200                ndev = rdma_read_gid_attr_ndev_rcu(attr);
 201                if (!IS_ERR(ndev) &&
 202                    ((!vlan_id && !is_vlan_dev(ndev)) ||
 203                     (vlan_id && is_vlan_dev(ndev) &&
 204                      vlan_dev_vlan_id(ndev) == vlan_id)) &&
 205                    attr->gid_type == IB_GID_TYPE_ROCE) {
 206                        rcu_read_unlock();
 207                        if (gid)
 208                                memcpy(gid, &attr->gid, SMC_GID_SIZE);
 209                        if (sgid_index)
 210                                *sgid_index = attr->index;
 211                        rdma_put_gid_attr(attr);
 212                        return 0;
 213                }
 214                rcu_read_unlock();
 215                rdma_put_gid_attr(attr);
 216        }
 217        return -ENODEV;
 218}
 219
 220static int smc_ib_remember_port_attr(struct smc_ib_device *smcibdev, u8 ibport)
 221{
 222        int rc;
 223
 224        memset(&smcibdev->pattr[ibport - 1], 0,
 225               sizeof(smcibdev->pattr[ibport - 1]));
 226        rc = ib_query_port(smcibdev->ibdev, ibport,
 227                           &smcibdev->pattr[ibport - 1]);
 228        if (rc)
 229                goto out;
 230        /* the SMC protocol requires specification of the RoCE MAC address */
 231        rc = smc_ib_fill_mac(smcibdev, ibport);
 232        if (rc)
 233                goto out;
 234        if (!smc_ib_is_valid_local_systemid() &&
 235            smc_ib_port_active(smcibdev, ibport))
 236                /* create unique system identifier */
 237                smc_ib_define_local_systemid(smcibdev, ibport);
 238out:
 239        return rc;
 240}
 241
 242/* process context wrapper for might_sleep smc_ib_remember_port_attr */
 243static void smc_ib_port_event_work(struct work_struct *work)
 244{
 245        struct smc_ib_device *smcibdev = container_of(
 246                work, struct smc_ib_device, port_event_work);
 247        u8 port_idx;
 248
 249        for_each_set_bit(port_idx, &smcibdev->port_event_mask, SMC_MAX_PORTS) {
 250                smc_ib_remember_port_attr(smcibdev, port_idx + 1);
 251                clear_bit(port_idx, &smcibdev->port_event_mask);
 252                if (!smc_ib_port_active(smcibdev, port_idx + 1)) {
 253                        set_bit(port_idx, smcibdev->ports_going_away);
 254                        smcr_port_err(smcibdev, port_idx + 1);
 255                } else {
 256                        clear_bit(port_idx, smcibdev->ports_going_away);
 257                        smcr_port_add(smcibdev, port_idx + 1);
 258                }
 259        }
 260}
 261
 262/* can be called in IRQ context */
 263static void smc_ib_global_event_handler(struct ib_event_handler *handler,
 264                                        struct ib_event *ibevent)
 265{
 266        struct smc_ib_device *smcibdev;
 267        bool schedule = false;
 268        u8 port_idx;
 269
 270        smcibdev = container_of(handler, struct smc_ib_device, event_handler);
 271
 272        switch (ibevent->event) {
 273        case IB_EVENT_DEVICE_FATAL:
 274                /* terminate all ports on device */
 275                for (port_idx = 0; port_idx < SMC_MAX_PORTS; port_idx++) {
 276                        set_bit(port_idx, &smcibdev->port_event_mask);
 277                        if (!test_and_set_bit(port_idx,
 278                                              smcibdev->ports_going_away))
 279                                schedule = true;
 280                }
 281                if (schedule)
 282                        schedule_work(&smcibdev->port_event_work);
 283                break;
 284        case IB_EVENT_PORT_ACTIVE:
 285                port_idx = ibevent->element.port_num - 1;
 286                if (port_idx >= SMC_MAX_PORTS)
 287                        break;
 288                set_bit(port_idx, &smcibdev->port_event_mask);
 289                if (test_and_clear_bit(port_idx, smcibdev->ports_going_away))
 290                        schedule_work(&smcibdev->port_event_work);
 291                break;
 292        case IB_EVENT_PORT_ERR:
 293                port_idx = ibevent->element.port_num - 1;
 294                if (port_idx >= SMC_MAX_PORTS)
 295                        break;
 296                set_bit(port_idx, &smcibdev->port_event_mask);
 297                if (!test_and_set_bit(port_idx, smcibdev->ports_going_away))
 298                        schedule_work(&smcibdev->port_event_work);
 299                break;
 300        case IB_EVENT_GID_CHANGE:
 301                port_idx = ibevent->element.port_num - 1;
 302                if (port_idx >= SMC_MAX_PORTS)
 303                        break;
 304                set_bit(port_idx, &smcibdev->port_event_mask);
 305                schedule_work(&smcibdev->port_event_work);
 306                break;
 307        default:
 308                break;
 309        }
 310}
 311
 312void smc_ib_dealloc_protection_domain(struct smc_link *lnk)
 313{
 314        if (lnk->roce_pd)
 315                ib_dealloc_pd(lnk->roce_pd);
 316        lnk->roce_pd = NULL;
 317}
 318
 319int smc_ib_create_protection_domain(struct smc_link *lnk)
 320{
 321        int rc;
 322
 323        lnk->roce_pd = ib_alloc_pd(lnk->smcibdev->ibdev, 0);
 324        rc = PTR_ERR_OR_ZERO(lnk->roce_pd);
 325        if (IS_ERR(lnk->roce_pd))
 326                lnk->roce_pd = NULL;
 327        return rc;
 328}
 329
 330static bool smcr_diag_is_dev_critical(struct smc_lgr_list *smc_lgr,
 331                                      struct smc_ib_device *smcibdev)
 332{
 333        struct smc_link_group *lgr;
 334        bool rc = false;
 335        int i;
 336
 337        spin_lock_bh(&smc_lgr->lock);
 338        list_for_each_entry(lgr, &smc_lgr->list, list) {
 339                if (lgr->is_smcd)
 340                        continue;
 341                for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
 342                        if (lgr->lnk[i].state == SMC_LNK_UNUSED ||
 343                            lgr->lnk[i].smcibdev != smcibdev)
 344                                continue;
 345                        if (lgr->type == SMC_LGR_SINGLE ||
 346                            lgr->type == SMC_LGR_ASYMMETRIC_LOCAL) {
 347                                rc = true;
 348                                goto out;
 349                        }
 350                }
 351        }
 352out:
 353        spin_unlock_bh(&smc_lgr->lock);
 354        return rc;
 355}
 356
 357static int smc_nl_handle_dev_port(struct sk_buff *skb,
 358                                  struct ib_device *ibdev,
 359                                  struct smc_ib_device *smcibdev,
 360                                  int port)
 361{
 362        char smc_pnet[SMC_MAX_PNETID_LEN + 1];
 363        struct nlattr *port_attrs;
 364        unsigned char port_state;
 365        int lnk_count = 0;
 366
 367        port_attrs = nla_nest_start(skb, SMC_NLA_DEV_PORT + port);
 368        if (!port_attrs)
 369                goto errout;
 370
 371        if (nla_put_u8(skb, SMC_NLA_DEV_PORT_PNET_USR,
 372                       smcibdev->pnetid_by_user[port]))
 373                goto errattr;
 374        memcpy(smc_pnet, &smcibdev->pnetid[port], SMC_MAX_PNETID_LEN);
 375        smc_pnet[SMC_MAX_PNETID_LEN] = 0;
 376        if (nla_put_string(skb, SMC_NLA_DEV_PORT_PNETID, smc_pnet))
 377                goto errattr;
 378        if (nla_put_u32(skb, SMC_NLA_DEV_PORT_NETDEV,
 379                        smcibdev->ndev_ifidx[port]))
 380                goto errattr;
 381        if (nla_put_u8(skb, SMC_NLA_DEV_PORT_VALID, 1))
 382                goto errattr;
 383        port_state = smc_ib_port_active(smcibdev, port + 1);
 384        if (nla_put_u8(skb, SMC_NLA_DEV_PORT_STATE, port_state))
 385                goto errattr;
 386        lnk_count = atomic_read(&smcibdev->lnk_cnt_by_port[port]);
 387        if (nla_put_u32(skb, SMC_NLA_DEV_PORT_LNK_CNT, lnk_count))
 388                goto errattr;
 389        nla_nest_end(skb, port_attrs);
 390        return 0;
 391errattr:
 392        nla_nest_cancel(skb, port_attrs);
 393errout:
 394        return -EMSGSIZE;
 395}
 396
 397static bool smc_nl_handle_pci_values(const struct smc_pci_dev *smc_pci_dev,
 398                                     struct sk_buff *skb)
 399{
 400        if (nla_put_u32(skb, SMC_NLA_DEV_PCI_FID, smc_pci_dev->pci_fid))
 401                return false;
 402        if (nla_put_u16(skb, SMC_NLA_DEV_PCI_CHID, smc_pci_dev->pci_pchid))
 403                return false;
 404        if (nla_put_u16(skb, SMC_NLA_DEV_PCI_VENDOR, smc_pci_dev->pci_vendor))
 405                return false;
 406        if (nla_put_u16(skb, SMC_NLA_DEV_PCI_DEVICE, smc_pci_dev->pci_device))
 407                return false;
 408        if (nla_put_string(skb, SMC_NLA_DEV_PCI_ID, smc_pci_dev->pci_id))
 409                return false;
 410        return true;
 411}
 412
 413static int smc_nl_handle_smcr_dev(struct smc_ib_device *smcibdev,
 414                                  struct sk_buff *skb,
 415                                  struct netlink_callback *cb)
 416{
 417        char smc_ibname[IB_DEVICE_NAME_MAX];
 418        struct smc_pci_dev smc_pci_dev;
 419        struct pci_dev *pci_dev;
 420        unsigned char is_crit;
 421        struct nlattr *attrs;
 422        void *nlh;
 423        int i;
 424
 425        nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
 426                          &smc_gen_nl_family, NLM_F_MULTI,
 427                          SMC_NETLINK_GET_DEV_SMCR);
 428        if (!nlh)
 429                goto errmsg;
 430        attrs = nla_nest_start(skb, SMC_GEN_DEV_SMCR);
 431        if (!attrs)
 432                goto errout;
 433        is_crit = smcr_diag_is_dev_critical(&smc_lgr_list, smcibdev);
 434        if (nla_put_u8(skb, SMC_NLA_DEV_IS_CRIT, is_crit))
 435                goto errattr;
 436        if (smcibdev->ibdev->dev.parent) {
 437                memset(&smc_pci_dev, 0, sizeof(smc_pci_dev));
 438                pci_dev = to_pci_dev(smcibdev->ibdev->dev.parent);
 439                smc_set_pci_values(pci_dev, &smc_pci_dev);
 440                if (!smc_nl_handle_pci_values(&smc_pci_dev, skb))
 441                        goto errattr;
 442        }
 443        snprintf(smc_ibname, sizeof(smc_ibname), "%s", smcibdev->ibdev->name);
 444        if (nla_put_string(skb, SMC_NLA_DEV_IB_NAME, smc_ibname))
 445                goto errattr;
 446        for (i = 1; i <= SMC_MAX_PORTS; i++) {
 447                if (!rdma_is_port_valid(smcibdev->ibdev, i))
 448                        continue;
 449                if (smc_nl_handle_dev_port(skb, smcibdev->ibdev,
 450                                           smcibdev, i - 1))
 451                        goto errattr;
 452        }
 453
 454        nla_nest_end(skb, attrs);
 455        genlmsg_end(skb, nlh);
 456        return 0;
 457
 458errattr:
 459        nla_nest_cancel(skb, attrs);
 460errout:
 461        genlmsg_cancel(skb, nlh);
 462errmsg:
 463        return -EMSGSIZE;
 464}
 465
 466static void smc_nl_prep_smcr_dev(struct smc_ib_devices *dev_list,
 467                                 struct sk_buff *skb,
 468                                 struct netlink_callback *cb)
 469{
 470        struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
 471        struct smc_ib_device *smcibdev;
 472        int snum = cb_ctx->pos[0];
 473        int num = 0;
 474
 475        mutex_lock(&dev_list->mutex);
 476        list_for_each_entry(smcibdev, &dev_list->list, list) {
 477                if (num < snum)
 478                        goto next;
 479                if (smc_nl_handle_smcr_dev(smcibdev, skb, cb))
 480                        goto errout;
 481next:
 482                num++;
 483        }
 484errout:
 485        mutex_unlock(&dev_list->mutex);
 486        cb_ctx->pos[0] = num;
 487}
 488
 489int smcr_nl_get_device(struct sk_buff *skb, struct netlink_callback *cb)
 490{
 491        smc_nl_prep_smcr_dev(&smc_ib_devices, skb, cb);
 492        return skb->len;
 493}
 494
 495static void smc_ib_qp_event_handler(struct ib_event *ibevent, void *priv)
 496{
 497        struct smc_link *lnk = (struct smc_link *)priv;
 498        struct smc_ib_device *smcibdev = lnk->smcibdev;
 499        u8 port_idx;
 500
 501        switch (ibevent->event) {
 502        case IB_EVENT_QP_FATAL:
 503        case IB_EVENT_QP_ACCESS_ERR:
 504                port_idx = ibevent->element.qp->port - 1;
 505                if (port_idx >= SMC_MAX_PORTS)
 506                        break;
 507                set_bit(port_idx, &smcibdev->port_event_mask);
 508                if (!test_and_set_bit(port_idx, smcibdev->ports_going_away))
 509                        schedule_work(&smcibdev->port_event_work);
 510                break;
 511        default:
 512                break;
 513        }
 514}
 515
 516void smc_ib_destroy_queue_pair(struct smc_link *lnk)
 517{
 518        if (lnk->roce_qp)
 519                ib_destroy_qp(lnk->roce_qp);
 520        lnk->roce_qp = NULL;
 521}
 522
 523/* create a queue pair within the protection domain for a link */
 524int smc_ib_create_queue_pair(struct smc_link *lnk)
 525{
 526        struct ib_qp_init_attr qp_attr = {
 527                .event_handler = smc_ib_qp_event_handler,
 528                .qp_context = lnk,
 529                .send_cq = lnk->smcibdev->roce_cq_send,
 530                .recv_cq = lnk->smcibdev->roce_cq_recv,
 531                .srq = NULL,
 532                .cap = {
 533                                /* include unsolicited rdma_writes as well,
 534                                 * there are max. 2 RDMA_WRITE per 1 WR_SEND
 535                                 */
 536                        .max_send_wr = SMC_WR_BUF_CNT * 3,
 537                        .max_recv_wr = SMC_WR_BUF_CNT * 3,
 538                        .max_send_sge = SMC_IB_MAX_SEND_SGE,
 539                        .max_recv_sge = 1,
 540                },
 541                .sq_sig_type = IB_SIGNAL_REQ_WR,
 542                .qp_type = IB_QPT_RC,
 543        };
 544        int rc;
 545
 546        lnk->roce_qp = ib_create_qp(lnk->roce_pd, &qp_attr);
 547        rc = PTR_ERR_OR_ZERO(lnk->roce_qp);
 548        if (IS_ERR(lnk->roce_qp))
 549                lnk->roce_qp = NULL;
 550        else
 551                smc_wr_remember_qp_attr(lnk);
 552        return rc;
 553}
 554
 555void smc_ib_put_memory_region(struct ib_mr *mr)
 556{
 557        ib_dereg_mr(mr);
 558}
 559
 560static int smc_ib_map_mr_sg(struct smc_buf_desc *buf_slot, u8 link_idx)
 561{
 562        unsigned int offset = 0;
 563        int sg_num;
 564
 565        /* map the largest prefix of a dma mapped SG list */
 566        sg_num = ib_map_mr_sg(buf_slot->mr_rx[link_idx],
 567                              buf_slot->sgt[link_idx].sgl,
 568                              buf_slot->sgt[link_idx].orig_nents,
 569                              &offset, PAGE_SIZE);
 570
 571        return sg_num;
 572}
 573
 574/* Allocate a memory region and map the dma mapped SG list of buf_slot */
 575int smc_ib_get_memory_region(struct ib_pd *pd, int access_flags,
 576                             struct smc_buf_desc *buf_slot, u8 link_idx)
 577{
 578        if (buf_slot->mr_rx[link_idx])
 579                return 0; /* already done */
 580
 581        buf_slot->mr_rx[link_idx] =
 582                ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG, 1 << buf_slot->order);
 583        if (IS_ERR(buf_slot->mr_rx[link_idx])) {
 584                int rc;
 585
 586                rc = PTR_ERR(buf_slot->mr_rx[link_idx]);
 587                buf_slot->mr_rx[link_idx] = NULL;
 588                return rc;
 589        }
 590
 591        if (smc_ib_map_mr_sg(buf_slot, link_idx) != 1)
 592                return -EINVAL;
 593
 594        return 0;
 595}
 596
 597/* synchronize buffer usage for cpu access */
 598void smc_ib_sync_sg_for_cpu(struct smc_link *lnk,
 599                            struct smc_buf_desc *buf_slot,
 600                            enum dma_data_direction data_direction)
 601{
 602        struct scatterlist *sg;
 603        unsigned int i;
 604
 605        /* for now there is just one DMA address */
 606        for_each_sg(buf_slot->sgt[lnk->link_idx].sgl, sg,
 607                    buf_slot->sgt[lnk->link_idx].nents, i) {
 608                if (!sg_dma_len(sg))
 609                        break;
 610                ib_dma_sync_single_for_cpu(lnk->smcibdev->ibdev,
 611                                           sg_dma_address(sg),
 612                                           sg_dma_len(sg),
 613                                           data_direction);
 614        }
 615}
 616
 617/* synchronize buffer usage for device access */
 618void smc_ib_sync_sg_for_device(struct smc_link *lnk,
 619                               struct smc_buf_desc *buf_slot,
 620                               enum dma_data_direction data_direction)
 621{
 622        struct scatterlist *sg;
 623        unsigned int i;
 624
 625        /* for now there is just one DMA address */
 626        for_each_sg(buf_slot->sgt[lnk->link_idx].sgl, sg,
 627                    buf_slot->sgt[lnk->link_idx].nents, i) {
 628                if (!sg_dma_len(sg))
 629                        break;
 630                ib_dma_sync_single_for_device(lnk->smcibdev->ibdev,
 631                                              sg_dma_address(sg),
 632                                              sg_dma_len(sg),
 633                                              data_direction);
 634        }
 635}
 636
 637/* Map a new TX or RX buffer SG-table to DMA */
 638int smc_ib_buf_map_sg(struct smc_link *lnk,
 639                      struct smc_buf_desc *buf_slot,
 640                      enum dma_data_direction data_direction)
 641{
 642        int mapped_nents;
 643
 644        mapped_nents = ib_dma_map_sg(lnk->smcibdev->ibdev,
 645                                     buf_slot->sgt[lnk->link_idx].sgl,
 646                                     buf_slot->sgt[lnk->link_idx].orig_nents,
 647                                     data_direction);
 648        if (!mapped_nents)
 649                return -ENOMEM;
 650
 651        return mapped_nents;
 652}
 653
 654void smc_ib_buf_unmap_sg(struct smc_link *lnk,
 655                         struct smc_buf_desc *buf_slot,
 656                         enum dma_data_direction data_direction)
 657{
 658        if (!buf_slot->sgt[lnk->link_idx].sgl->dma_address)
 659                return; /* already unmapped */
 660
 661        ib_dma_unmap_sg(lnk->smcibdev->ibdev,
 662                        buf_slot->sgt[lnk->link_idx].sgl,
 663                        buf_slot->sgt[lnk->link_idx].orig_nents,
 664                        data_direction);
 665        buf_slot->sgt[lnk->link_idx].sgl->dma_address = 0;
 666}
 667
 668long smc_ib_setup_per_ibdev(struct smc_ib_device *smcibdev)
 669{
 670        struct ib_cq_init_attr cqattr = {
 671                .cqe = SMC_MAX_CQE, .comp_vector = 0 };
 672        int cqe_size_order, smc_order;
 673        long rc;
 674
 675        mutex_lock(&smcibdev->mutex);
 676        rc = 0;
 677        if (smcibdev->initialized)
 678                goto out;
 679        /* the calculated number of cq entries fits to mlx5 cq allocation */
 680        cqe_size_order = cache_line_size() == 128 ? 7 : 6;
 681        smc_order = MAX_ORDER - cqe_size_order - 1;
 682        if (SMC_MAX_CQE + 2 > (0x00000001 << smc_order) * PAGE_SIZE)
 683                cqattr.cqe = (0x00000001 << smc_order) * PAGE_SIZE - 2;
 684        smcibdev->roce_cq_send = ib_create_cq(smcibdev->ibdev,
 685                                              smc_wr_tx_cq_handler, NULL,
 686                                              smcibdev, &cqattr);
 687        rc = PTR_ERR_OR_ZERO(smcibdev->roce_cq_send);
 688        if (IS_ERR(smcibdev->roce_cq_send)) {
 689                smcibdev->roce_cq_send = NULL;
 690                goto out;
 691        }
 692        smcibdev->roce_cq_recv = ib_create_cq(smcibdev->ibdev,
 693                                              smc_wr_rx_cq_handler, NULL,
 694                                              smcibdev, &cqattr);
 695        rc = PTR_ERR_OR_ZERO(smcibdev->roce_cq_recv);
 696        if (IS_ERR(smcibdev->roce_cq_recv)) {
 697                smcibdev->roce_cq_recv = NULL;
 698                goto err;
 699        }
 700        smc_wr_add_dev(smcibdev);
 701        smcibdev->initialized = 1;
 702        goto out;
 703
 704err:
 705        ib_destroy_cq(smcibdev->roce_cq_send);
 706out:
 707        mutex_unlock(&smcibdev->mutex);
 708        return rc;
 709}
 710
 711static void smc_ib_cleanup_per_ibdev(struct smc_ib_device *smcibdev)
 712{
 713        mutex_lock(&smcibdev->mutex);
 714        if (!smcibdev->initialized)
 715                goto out;
 716        smcibdev->initialized = 0;
 717        ib_destroy_cq(smcibdev->roce_cq_recv);
 718        ib_destroy_cq(smcibdev->roce_cq_send);
 719        smc_wr_remove_dev(smcibdev);
 720out:
 721        mutex_unlock(&smcibdev->mutex);
 722}
 723
 724static struct ib_client smc_ib_client;
 725
 726static void smc_copy_netdev_ifindex(struct smc_ib_device *smcibdev, int port)
 727{
 728        struct ib_device *ibdev = smcibdev->ibdev;
 729        struct net_device *ndev;
 730
 731        if (!ibdev->ops.get_netdev)
 732                return;
 733        ndev = ibdev->ops.get_netdev(ibdev, port + 1);
 734        if (ndev) {
 735                smcibdev->ndev_ifidx[port] = ndev->ifindex;
 736                dev_put(ndev);
 737        }
 738}
 739
 740void smc_ib_ndev_change(struct net_device *ndev, unsigned long event)
 741{
 742        struct smc_ib_device *smcibdev;
 743        struct ib_device *libdev;
 744        struct net_device *lndev;
 745        u8 port_cnt;
 746        int i;
 747
 748        mutex_lock(&smc_ib_devices.mutex);
 749        list_for_each_entry(smcibdev, &smc_ib_devices.list, list) {
 750                port_cnt = smcibdev->ibdev->phys_port_cnt;
 751                for (i = 0; i < min_t(size_t, port_cnt, SMC_MAX_PORTS); i++) {
 752                        libdev = smcibdev->ibdev;
 753                        if (!libdev->ops.get_netdev)
 754                                continue;
 755                        lndev = libdev->ops.get_netdev(libdev, i + 1);
 756                        if (lndev)
 757                                dev_put(lndev);
 758                        if (lndev != ndev)
 759                                continue;
 760                        if (event == NETDEV_REGISTER)
 761                                smcibdev->ndev_ifidx[i] = ndev->ifindex;
 762                        if (event == NETDEV_UNREGISTER)
 763                                smcibdev->ndev_ifidx[i] = 0;
 764                }
 765        }
 766        mutex_unlock(&smc_ib_devices.mutex);
 767}
 768
 769/* callback function for ib_register_client() */
 770static int smc_ib_add_dev(struct ib_device *ibdev)
 771{
 772        struct smc_ib_device *smcibdev;
 773        u8 port_cnt;
 774        int i;
 775
 776        if (ibdev->node_type != RDMA_NODE_IB_CA)
 777                return -EOPNOTSUPP;
 778
 779        smcibdev = kzalloc(sizeof(*smcibdev), GFP_KERNEL);
 780        if (!smcibdev)
 781                return -ENOMEM;
 782
 783        smcibdev->ibdev = ibdev;
 784        INIT_WORK(&smcibdev->port_event_work, smc_ib_port_event_work);
 785        atomic_set(&smcibdev->lnk_cnt, 0);
 786        init_waitqueue_head(&smcibdev->lnks_deleted);
 787        mutex_init(&smcibdev->mutex);
 788        mutex_lock(&smc_ib_devices.mutex);
 789        list_add_tail(&smcibdev->list, &smc_ib_devices.list);
 790        mutex_unlock(&smc_ib_devices.mutex);
 791        ib_set_client_data(ibdev, &smc_ib_client, smcibdev);
 792        INIT_IB_EVENT_HANDLER(&smcibdev->event_handler, smcibdev->ibdev,
 793                              smc_ib_global_event_handler);
 794        ib_register_event_handler(&smcibdev->event_handler);
 795
 796        /* trigger reading of the port attributes */
 797        port_cnt = smcibdev->ibdev->phys_port_cnt;
 798        pr_warn_ratelimited("smc: adding ib device %s with port count %d\n",
 799                            smcibdev->ibdev->name, port_cnt);
 800        for (i = 0;
 801             i < min_t(size_t, port_cnt, SMC_MAX_PORTS);
 802             i++) {
 803                set_bit(i, &smcibdev->port_event_mask);
 804                /* determine pnetids of the port */
 805                if (smc_pnetid_by_dev_port(ibdev->dev.parent, i,
 806                                           smcibdev->pnetid[i]))
 807                        smc_pnetid_by_table_ib(smcibdev, i + 1);
 808                smc_copy_netdev_ifindex(smcibdev, i);
 809                pr_warn_ratelimited("smc:    ib device %s port %d has pnetid "
 810                                    "%.16s%s\n",
 811                                    smcibdev->ibdev->name, i + 1,
 812                                    smcibdev->pnetid[i],
 813                                    smcibdev->pnetid_by_user[i] ?
 814                                     " (user defined)" :
 815                                     "");
 816        }
 817        schedule_work(&smcibdev->port_event_work);
 818        return 0;
 819}
 820
 821/* callback function for ib_unregister_client() */
 822static void smc_ib_remove_dev(struct ib_device *ibdev, void *client_data)
 823{
 824        struct smc_ib_device *smcibdev = client_data;
 825
 826        mutex_lock(&smc_ib_devices.mutex);
 827        list_del_init(&smcibdev->list); /* remove from smc_ib_devices */
 828        mutex_unlock(&smc_ib_devices.mutex);
 829        pr_warn_ratelimited("smc: removing ib device %s\n",
 830                            smcibdev->ibdev->name);
 831        smc_smcr_terminate_all(smcibdev);
 832        smc_ib_cleanup_per_ibdev(smcibdev);
 833        ib_unregister_event_handler(&smcibdev->event_handler);
 834        cancel_work_sync(&smcibdev->port_event_work);
 835        kfree(smcibdev);
 836}
 837
 838static struct ib_client smc_ib_client = {
 839        .name   = "smc_ib",
 840        .add    = smc_ib_add_dev,
 841        .remove = smc_ib_remove_dev,
 842};
 843
 844int __init smc_ib_register_client(void)
 845{
 846        smc_ib_init_local_systemid();
 847        return ib_register_client(&smc_ib_client);
 848}
 849
 850void smc_ib_unregister_client(void)
 851{
 852        ib_unregister_client(&smc_ib_client);
 853}
 854