linux/net/caif/cfcnfg.c
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   1/*
   2 * Copyright (C) ST-Ericsson AB 2010
   3 * Author:      Sjur Brendeland
   4 * License terms: GNU General Public License (GPL) version 2
   5 */
   6
   7#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
   8
   9#include <linux/kernel.h>
  10#include <linux/stddef.h>
  11#include <linux/slab.h>
  12#include <linux/netdevice.h>
  13#include <linux/module.h>
  14#include <net/caif/caif_layer.h>
  15#include <net/caif/cfpkt.h>
  16#include <net/caif/cfcnfg.h>
  17#include <net/caif/cfctrl.h>
  18#include <net/caif/cfmuxl.h>
  19#include <net/caif/cffrml.h>
  20#include <net/caif/cfserl.h>
  21#include <net/caif/cfsrvl.h>
  22#include <net/caif/caif_dev.h>
  23
  24#define container_obj(layr) container_of(layr, struct cfcnfg, layer)
  25
  26/* Information about CAIF physical interfaces held by Config Module in order
  27 * to manage physical interfaces
  28 */
  29struct cfcnfg_phyinfo {
  30        struct list_head node;
  31        bool up;
  32
  33        /* Pointer to the layer below the MUX (framing layer) */
  34        struct cflayer *frm_layer;
  35        /* Pointer to the lowest actual physical layer */
  36        struct cflayer *phy_layer;
  37        /* Unique identifier of the physical interface */
  38        unsigned int id;
  39        /* Preference of the physical in interface */
  40        enum cfcnfg_phy_preference pref;
  41
  42        /* Information about the physical device */
  43        struct dev_info dev_info;
  44
  45        /* Interface index */
  46        int ifindex;
  47
  48        /* Protocol head room added for CAIF link layer */
  49        int head_room;
  50
  51        /* Use Start of frame checksum */
  52        bool use_fcs;
  53};
  54
  55struct cfcnfg {
  56        struct cflayer layer;
  57        struct cflayer *ctrl;
  58        struct cflayer *mux;
  59        struct list_head phys;
  60        struct mutex lock;
  61};
  62
  63static void cfcnfg_linkup_rsp(struct cflayer *layer, u8 channel_id,
  64                              enum cfctrl_srv serv, u8 phyid,
  65                              struct cflayer *adapt_layer);
  66static void cfcnfg_linkdestroy_rsp(struct cflayer *layer, u8 channel_id);
  67static void cfcnfg_reject_rsp(struct cflayer *layer, u8 channel_id,
  68                              struct cflayer *adapt_layer);
  69static void cfctrl_resp_func(void);
  70static void cfctrl_enum_resp(void);
  71
  72struct cfcnfg *cfcnfg_create(void)
  73{
  74        struct cfcnfg *this;
  75        struct cfctrl_rsp *resp;
  76
  77        might_sleep();
  78
  79        /* Initiate this layer */
  80        this = kzalloc(sizeof(struct cfcnfg), GFP_ATOMIC);
  81        if (!this)
  82                return NULL;
  83        this->mux = cfmuxl_create();
  84        if (!this->mux)
  85                goto out_of_mem;
  86        this->ctrl = cfctrl_create();
  87        if (!this->ctrl)
  88                goto out_of_mem;
  89        /* Initiate response functions */
  90        resp = cfctrl_get_respfuncs(this->ctrl);
  91        resp->enum_rsp = cfctrl_enum_resp;
  92        resp->linkerror_ind = cfctrl_resp_func;
  93        resp->linkdestroy_rsp = cfcnfg_linkdestroy_rsp;
  94        resp->sleep_rsp = cfctrl_resp_func;
  95        resp->wake_rsp = cfctrl_resp_func;
  96        resp->restart_rsp = cfctrl_resp_func;
  97        resp->radioset_rsp = cfctrl_resp_func;
  98        resp->linksetup_rsp = cfcnfg_linkup_rsp;
  99        resp->reject_rsp = cfcnfg_reject_rsp;
 100        INIT_LIST_HEAD(&this->phys);
 101
 102        cfmuxl_set_uplayer(this->mux, this->ctrl, 0);
 103        layer_set_dn(this->ctrl, this->mux);
 104        layer_set_up(this->ctrl, this);
 105        mutex_init(&this->lock);
 106
 107        return this;
 108out_of_mem:
 109        synchronize_rcu();
 110
 111        kfree(this->mux);
 112        kfree(this->ctrl);
 113        kfree(this);
 114        return NULL;
 115}
 116
 117void cfcnfg_remove(struct cfcnfg *cfg)
 118{
 119        might_sleep();
 120        if (cfg) {
 121                synchronize_rcu();
 122
 123                kfree(cfg->mux);
 124                cfctrl_remove(cfg->ctrl);
 125                kfree(cfg);
 126        }
 127}
 128
 129static void cfctrl_resp_func(void)
 130{
 131}
 132
 133static struct cfcnfg_phyinfo *cfcnfg_get_phyinfo_rcu(struct cfcnfg *cnfg,
 134                                                     u8 phyid)
 135{
 136        struct cfcnfg_phyinfo *phy;
 137
 138        list_for_each_entry_rcu(phy, &cnfg->phys, node)
 139                if (phy->id == phyid)
 140                        return phy;
 141        return NULL;
 142}
 143
 144static void cfctrl_enum_resp(void)
 145{
 146}
 147
 148static struct dev_info *cfcnfg_get_phyid(struct cfcnfg *cnfg,
 149                                  enum cfcnfg_phy_preference phy_pref)
 150{
 151        /* Try to match with specified preference */
 152        struct cfcnfg_phyinfo *phy;
 153
 154        list_for_each_entry_rcu(phy, &cnfg->phys, node) {
 155                if (phy->up && phy->pref == phy_pref &&
 156                                phy->frm_layer != NULL)
 157
 158                        return &phy->dev_info;
 159        }
 160
 161        /* Otherwise just return something */
 162        list_for_each_entry_rcu(phy, &cnfg->phys, node)
 163                if (phy->up)
 164                        return &phy->dev_info;
 165
 166        return NULL;
 167}
 168
 169static int cfcnfg_get_id_from_ifi(struct cfcnfg *cnfg, int ifi)
 170{
 171        struct cfcnfg_phyinfo *phy;
 172
 173        list_for_each_entry_rcu(phy, &cnfg->phys, node)
 174                if (phy->ifindex == ifi && phy->up)
 175                        return phy->id;
 176        return -ENODEV;
 177}
 178
 179int caif_disconnect_client(struct net *net, struct cflayer *adap_layer)
 180{
 181        u8 channel_id;
 182        struct cfcnfg *cfg = get_cfcnfg(net);
 183
 184        caif_assert(adap_layer != NULL);
 185        cfctrl_cancel_req(cfg->ctrl, adap_layer);
 186        channel_id = adap_layer->id;
 187        if (channel_id != 0) {
 188                struct cflayer *servl;
 189                servl = cfmuxl_remove_uplayer(cfg->mux, channel_id);
 190                cfctrl_linkdown_req(cfg->ctrl, channel_id, adap_layer);
 191                if (servl != NULL)
 192                        layer_set_up(servl, NULL);
 193        } else
 194                pr_debug("nothing to disconnect\n");
 195
 196        /* Do RCU sync before initiating cleanup */
 197        synchronize_rcu();
 198        if (adap_layer->ctrlcmd != NULL)
 199                adap_layer->ctrlcmd(adap_layer, CAIF_CTRLCMD_DEINIT_RSP, 0);
 200        return 0;
 201
 202}
 203EXPORT_SYMBOL(caif_disconnect_client);
 204
 205static void cfcnfg_linkdestroy_rsp(struct cflayer *layer, u8 channel_id)
 206{
 207}
 208
 209static const int protohead[CFCTRL_SRV_MASK] = {
 210        [CFCTRL_SRV_VEI] = 4,
 211        [CFCTRL_SRV_DATAGRAM] = 7,
 212        [CFCTRL_SRV_UTIL] = 4,
 213        [CFCTRL_SRV_RFM] = 3,
 214        [CFCTRL_SRV_DBG] = 3,
 215};
 216
 217
 218static int caif_connect_req_to_link_param(struct cfcnfg *cnfg,
 219                                          struct caif_connect_request *s,
 220                                          struct cfctrl_link_param *l)
 221{
 222        struct dev_info *dev_info;
 223        enum cfcnfg_phy_preference pref;
 224        int res;
 225
 226        memset(l, 0, sizeof(*l));
 227        /* In caif protocol low value is high priority */
 228        l->priority = CAIF_PRIO_MAX - s->priority + 1;
 229
 230        if (s->ifindex != 0) {
 231                res = cfcnfg_get_id_from_ifi(cnfg, s->ifindex);
 232                if (res < 0)
 233                        return res;
 234                l->phyid = res;
 235        } else {
 236                switch (s->link_selector) {
 237                case CAIF_LINK_HIGH_BANDW:
 238                        pref = CFPHYPREF_HIGH_BW;
 239                        break;
 240                case CAIF_LINK_LOW_LATENCY:
 241                        pref = CFPHYPREF_LOW_LAT;
 242                        break;
 243                default:
 244                        return -EINVAL;
 245                }
 246                dev_info = cfcnfg_get_phyid(cnfg, pref);
 247                if (dev_info == NULL)
 248                        return -ENODEV;
 249                l->phyid = dev_info->id;
 250        }
 251        switch (s->protocol) {
 252        case CAIFPROTO_AT:
 253                l->linktype = CFCTRL_SRV_VEI;
 254                l->endpoint = (s->sockaddr.u.at.type >> 2) & 0x3;
 255                l->chtype = s->sockaddr.u.at.type & 0x3;
 256                break;
 257        case CAIFPROTO_DATAGRAM:
 258                l->linktype = CFCTRL_SRV_DATAGRAM;
 259                l->chtype = 0x00;
 260                l->u.datagram.connid = s->sockaddr.u.dgm.connection_id;
 261                break;
 262        case CAIFPROTO_DATAGRAM_LOOP:
 263                l->linktype = CFCTRL_SRV_DATAGRAM;
 264                l->chtype = 0x03;
 265                l->endpoint = 0x00;
 266                l->u.datagram.connid = s->sockaddr.u.dgm.connection_id;
 267                break;
 268        case CAIFPROTO_RFM:
 269                l->linktype = CFCTRL_SRV_RFM;
 270                l->u.datagram.connid = s->sockaddr.u.rfm.connection_id;
 271                strncpy(l->u.rfm.volume, s->sockaddr.u.rfm.volume,
 272                        sizeof(l->u.rfm.volume)-1);
 273                l->u.rfm.volume[sizeof(l->u.rfm.volume)-1] = 0;
 274                break;
 275        case CAIFPROTO_UTIL:
 276                l->linktype = CFCTRL_SRV_UTIL;
 277                l->endpoint = 0x00;
 278                l->chtype = 0x00;
 279                strncpy(l->u.utility.name, s->sockaddr.u.util.service,
 280                        sizeof(l->u.utility.name)-1);
 281                l->u.utility.name[sizeof(l->u.utility.name)-1] = 0;
 282                caif_assert(sizeof(l->u.utility.name) > 10);
 283                l->u.utility.paramlen = s->param.size;
 284                if (l->u.utility.paramlen > sizeof(l->u.utility.params))
 285                        l->u.utility.paramlen = sizeof(l->u.utility.params);
 286
 287                memcpy(l->u.utility.params, s->param.data,
 288                       l->u.utility.paramlen);
 289
 290                break;
 291        case CAIFPROTO_DEBUG:
 292                l->linktype = CFCTRL_SRV_DBG;
 293                l->endpoint = s->sockaddr.u.dbg.service;
 294                l->chtype = s->sockaddr.u.dbg.type;
 295                break;
 296        default:
 297                return -EINVAL;
 298        }
 299        return 0;
 300}
 301
 302int caif_connect_client(struct net *net, struct caif_connect_request *conn_req,
 303                        struct cflayer *adap_layer, int *ifindex,
 304                        int *proto_head, int *proto_tail)
 305{
 306        struct cflayer *frml;
 307        struct cfcnfg_phyinfo *phy;
 308        int err;
 309        struct cfctrl_link_param param;
 310        struct cfcnfg *cfg = get_cfcnfg(net);
 311
 312        rcu_read_lock();
 313        err = caif_connect_req_to_link_param(cfg, conn_req, &param);
 314        if (err)
 315                goto unlock;
 316
 317        phy = cfcnfg_get_phyinfo_rcu(cfg, param.phyid);
 318        if (!phy) {
 319                err = -ENODEV;
 320                goto unlock;
 321        }
 322        err = -EINVAL;
 323
 324        if (adap_layer == NULL) {
 325                pr_err("adap_layer is zero\n");
 326                goto unlock;
 327        }
 328        if (adap_layer->receive == NULL) {
 329                pr_err("adap_layer->receive is NULL\n");
 330                goto unlock;
 331        }
 332        if (adap_layer->ctrlcmd == NULL) {
 333                pr_err("adap_layer->ctrlcmd == NULL\n");
 334                goto unlock;
 335        }
 336
 337        err = -ENODEV;
 338        frml = phy->frm_layer;
 339        if (frml == NULL) {
 340                pr_err("Specified PHY type does not exist!\n");
 341                goto unlock;
 342        }
 343        caif_assert(param.phyid == phy->id);
 344        caif_assert(phy->frm_layer->id ==
 345                     param.phyid);
 346        caif_assert(phy->phy_layer->id ==
 347                     param.phyid);
 348
 349        *ifindex = phy->ifindex;
 350        *proto_tail = 2;
 351        *proto_head = protohead[param.linktype] + phy->head_room;
 352
 353        rcu_read_unlock();
 354
 355        /* FIXME: ENUMERATE INITIALLY WHEN ACTIVATING PHYSICAL INTERFACE */
 356        cfctrl_enum_req(cfg->ctrl, param.phyid);
 357        return cfctrl_linkup_request(cfg->ctrl, &param, adap_layer);
 358
 359unlock:
 360        rcu_read_unlock();
 361        return err;
 362}
 363EXPORT_SYMBOL(caif_connect_client);
 364
 365static void cfcnfg_reject_rsp(struct cflayer *layer, u8 channel_id,
 366                              struct cflayer *adapt_layer)
 367{
 368        if (adapt_layer != NULL && adapt_layer->ctrlcmd != NULL)
 369                adapt_layer->ctrlcmd(adapt_layer,
 370                                     CAIF_CTRLCMD_INIT_FAIL_RSP, 0);
 371}
 372
 373static void
 374cfcnfg_linkup_rsp(struct cflayer *layer, u8 channel_id, enum cfctrl_srv serv,
 375                  u8 phyid, struct cflayer *adapt_layer)
 376{
 377        struct cfcnfg *cnfg = container_obj(layer);
 378        struct cflayer *servicel = NULL;
 379        struct cfcnfg_phyinfo *phyinfo;
 380        struct net_device *netdev;
 381
 382        if (channel_id == 0) {
 383                pr_warn("received channel_id zero\n");
 384                if (adapt_layer != NULL && adapt_layer->ctrlcmd != NULL)
 385                        adapt_layer->ctrlcmd(adapt_layer,
 386                                                CAIF_CTRLCMD_INIT_FAIL_RSP, 0);
 387                return;
 388        }
 389
 390        rcu_read_lock();
 391
 392        if (adapt_layer == NULL) {
 393                pr_debug("link setup response but no client exist,"
 394                                "send linkdown back\n");
 395                cfctrl_linkdown_req(cnfg->ctrl, channel_id, NULL);
 396                goto unlock;
 397        }
 398
 399        caif_assert(cnfg != NULL);
 400        caif_assert(phyid != 0);
 401
 402        phyinfo = cfcnfg_get_phyinfo_rcu(cnfg, phyid);
 403        if (phyinfo == NULL) {
 404                pr_err("ERROR: Link Layer Device disappeared"
 405                                "while connecting\n");
 406                goto unlock;
 407        }
 408
 409        caif_assert(phyinfo != NULL);
 410        caif_assert(phyinfo->id == phyid);
 411        caif_assert(phyinfo->phy_layer != NULL);
 412        caif_assert(phyinfo->phy_layer->id == phyid);
 413
 414        adapt_layer->id = channel_id;
 415
 416        switch (serv) {
 417        case CFCTRL_SRV_VEI:
 418                servicel = cfvei_create(channel_id, &phyinfo->dev_info);
 419                break;
 420        case CFCTRL_SRV_DATAGRAM:
 421                servicel = cfdgml_create(channel_id,
 422                                        &phyinfo->dev_info);
 423                break;
 424        case CFCTRL_SRV_RFM:
 425                netdev = phyinfo->dev_info.dev;
 426                servicel = cfrfml_create(channel_id, &phyinfo->dev_info,
 427                                                netdev->mtu);
 428                break;
 429        case CFCTRL_SRV_UTIL:
 430                servicel = cfutill_create(channel_id, &phyinfo->dev_info);
 431                break;
 432        case CFCTRL_SRV_VIDEO:
 433                servicel = cfvidl_create(channel_id, &phyinfo->dev_info);
 434                break;
 435        case CFCTRL_SRV_DBG:
 436                servicel = cfdbgl_create(channel_id, &phyinfo->dev_info);
 437                break;
 438        default:
 439                pr_err("Protocol error. Link setup response "
 440                                "- unknown channel type\n");
 441                goto unlock;
 442        }
 443        if (!servicel)
 444                goto unlock;
 445        layer_set_dn(servicel, cnfg->mux);
 446        cfmuxl_set_uplayer(cnfg->mux, servicel, channel_id);
 447        layer_set_up(servicel, adapt_layer);
 448        layer_set_dn(adapt_layer, servicel);
 449
 450        rcu_read_unlock();
 451
 452        servicel->ctrlcmd(servicel, CAIF_CTRLCMD_INIT_RSP, 0);
 453        return;
 454unlock:
 455        rcu_read_unlock();
 456}
 457
 458void
 459cfcnfg_add_phy_layer(struct cfcnfg *cnfg,
 460                     struct net_device *dev, struct cflayer *phy_layer,
 461                     enum cfcnfg_phy_preference pref,
 462                     struct cflayer *link_support,
 463                     bool fcs, int head_room)
 464{
 465        struct cflayer *frml;
 466        struct cfcnfg_phyinfo *phyinfo = NULL;
 467        int i;
 468        u8 phyid;
 469
 470        mutex_lock(&cnfg->lock);
 471
 472        /* CAIF protocol allow maximum 6 link-layers */
 473        for (i = 0; i < 7; i++) {
 474                phyid = (dev->ifindex + i) & 0x7;
 475                if (phyid == 0)
 476                        continue;
 477                if (cfcnfg_get_phyinfo_rcu(cnfg, phyid) == NULL)
 478                        goto got_phyid;
 479        }
 480        pr_warn("Too many CAIF Link Layers (max 6)\n");
 481        goto out;
 482
 483got_phyid:
 484        phyinfo = kzalloc(sizeof(struct cfcnfg_phyinfo), GFP_ATOMIC);
 485        if (!phyinfo)
 486                goto out_err;
 487
 488        phy_layer->id = phyid;
 489        phyinfo->pref = pref;
 490        phyinfo->id = phyid;
 491        phyinfo->dev_info.id = phyid;
 492        phyinfo->dev_info.dev = dev;
 493        phyinfo->phy_layer = phy_layer;
 494        phyinfo->ifindex = dev->ifindex;
 495        phyinfo->head_room = head_room;
 496        phyinfo->use_fcs = fcs;
 497
 498        frml = cffrml_create(phyid, fcs);
 499
 500        if (!frml)
 501                goto out_err;
 502        phyinfo->frm_layer = frml;
 503        layer_set_up(frml, cnfg->mux);
 504
 505        if (link_support != NULL) {
 506                link_support->id = phyid;
 507                layer_set_dn(frml, link_support);
 508                layer_set_up(link_support, frml);
 509                layer_set_dn(link_support, phy_layer);
 510                layer_set_up(phy_layer, link_support);
 511        } else {
 512                layer_set_dn(frml, phy_layer);
 513                layer_set_up(phy_layer, frml);
 514        }
 515
 516        list_add_rcu(&phyinfo->node, &cnfg->phys);
 517out:
 518        mutex_unlock(&cnfg->lock);
 519        return;
 520
 521out_err:
 522        kfree(phyinfo);
 523        mutex_unlock(&cnfg->lock);
 524}
 525EXPORT_SYMBOL(cfcnfg_add_phy_layer);
 526
 527int cfcnfg_set_phy_state(struct cfcnfg *cnfg, struct cflayer *phy_layer,
 528                         bool up)
 529{
 530        struct cfcnfg_phyinfo *phyinfo;
 531
 532        rcu_read_lock();
 533        phyinfo = cfcnfg_get_phyinfo_rcu(cnfg, phy_layer->id);
 534        if (phyinfo == NULL) {
 535                rcu_read_unlock();
 536                return -ENODEV;
 537        }
 538
 539        if (phyinfo->up == up) {
 540                rcu_read_unlock();
 541                return 0;
 542        }
 543        phyinfo->up = up;
 544
 545        if (up) {
 546                cffrml_hold(phyinfo->frm_layer);
 547                cfmuxl_set_dnlayer(cnfg->mux, phyinfo->frm_layer,
 548                                        phy_layer->id);
 549        } else {
 550                cfmuxl_remove_dnlayer(cnfg->mux, phy_layer->id);
 551                cffrml_put(phyinfo->frm_layer);
 552        }
 553
 554        rcu_read_unlock();
 555        return 0;
 556}
 557EXPORT_SYMBOL(cfcnfg_set_phy_state);
 558
 559int cfcnfg_del_phy_layer(struct cfcnfg *cnfg, struct cflayer *phy_layer)
 560{
 561        struct cflayer *frml, *frml_dn;
 562        u16 phyid;
 563        struct cfcnfg_phyinfo *phyinfo;
 564
 565        might_sleep();
 566
 567        mutex_lock(&cnfg->lock);
 568
 569        phyid = phy_layer->id;
 570        phyinfo = cfcnfg_get_phyinfo_rcu(cnfg, phyid);
 571
 572        if (phyinfo == NULL) {
 573                mutex_unlock(&cnfg->lock);
 574                return 0;
 575        }
 576        caif_assert(phyid == phyinfo->id);
 577        caif_assert(phy_layer == phyinfo->phy_layer);
 578        caif_assert(phy_layer->id == phyid);
 579        caif_assert(phyinfo->frm_layer->id == phyid);
 580
 581        list_del_rcu(&phyinfo->node);
 582        synchronize_rcu();
 583
 584        /* Fail if reference count is not zero */
 585        if (cffrml_refcnt_read(phyinfo->frm_layer) != 0) {
 586                pr_info("Wait for device inuse\n");
 587                list_add_rcu(&phyinfo->node, &cnfg->phys);
 588                mutex_unlock(&cnfg->lock);
 589                return -EAGAIN;
 590        }
 591
 592        frml = phyinfo->frm_layer;
 593        frml_dn = frml->dn;
 594        cffrml_set_uplayer(frml, NULL);
 595        cffrml_set_dnlayer(frml, NULL);
 596        if (phy_layer != frml_dn) {
 597                layer_set_up(frml_dn, NULL);
 598                layer_set_dn(frml_dn, NULL);
 599        }
 600        layer_set_up(phy_layer, NULL);
 601
 602        if (phyinfo->phy_layer != frml_dn)
 603                kfree(frml_dn);
 604
 605        cffrml_free(frml);
 606        kfree(phyinfo);
 607        mutex_unlock(&cnfg->lock);
 608
 609        return 0;
 610}
 611EXPORT_SYMBOL(cfcnfg_del_phy_layer);
 612