git.oblomov.eu Git - linux-2.6/blob - arch/sparc/kernel/viohs.c

   1 /* viohs.c: LDOM Virtual I/O handshake helper layer.
   2  *
   3  * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/module.h>
   8 #include <linux/string.h>
   9 #include <linux/delay.h>
  10 #include <linux/sched.h>
  11 #include <linux/slab.h>
  12
  13 #include <asm/ldc.h>
  14 #include <asm/vio.h>
  15
  16 int vio_ldc_send(struct vio_driver_state *vio, void *data, int len)
  17 {
  18         int err, limit = 1000;
  19
  20         err = -EINVAL;
  21         while (limit-- > 0) {
  22                 err = ldc_write(vio->lp, data, len);
  23                 if (!err || (err != -EAGAIN))
  24                         break;
  25                 udelay(1);
  26         }
  27
  28         return err;
  29 }
  30 EXPORT_SYMBOL(vio_ldc_send);
  31
  32 static int send_ctrl(struct vio_driver_state *vio,
  33                      struct vio_msg_tag *tag, int len)
  34 {
  35         tag->sid = vio_send_sid(vio);
  36         return vio_ldc_send(vio, tag, len);
  37 }
  38
  39 static void init_tag(struct vio_msg_tag *tag, u8 type, u8 stype, u16 stype_env)
  40 {
  41         tag->type = type;
  42         tag->stype = stype;
  43         tag->stype_env = stype_env;
  44 }
  45
  46 static int send_version(struct vio_driver_state *vio, u16 major, u16 minor)
  47 {
  48         struct vio_ver_info pkt;
  49
  50         vio->_local_sid = (u32) sched_clock();
  51
  52         memset(&pkt, 0, sizeof(pkt));
  53         init_tag(&pkt.tag, VIO_TYPE_CTRL, VIO_SUBTYPE_INFO, VIO_VER_INFO);
  54         pkt.major = major;
  55         pkt.minor = minor;
  56         pkt.dev_class = vio->dev_class;
  57
  58         viodbg(HS, "SEND VERSION INFO maj[%u] min[%u] devclass[%u]\n",
  59                major, minor, vio->dev_class);
  60
  61         return send_ctrl(vio, &pkt.tag, sizeof(pkt));
  62 }
  63
  64 static int start_handshake(struct vio_driver_state *vio)
  65 {
  66         int err;
  67
  68         viodbg(HS, "START HANDSHAKE\n");
  69
  70         vio->hs_state = VIO_HS_INVALID;
  71
  72         err = send_version(vio,
  73                            vio->ver_table[0].major,
  74                            vio->ver_table[0].minor);
  75         if (err < 0)
  76                 return err;
  77
  78         return 0;
  79 }
  80
  81 static void flush_rx_dring(struct vio_driver_state *vio)
  82 {
  83         struct vio_dring_state *dr;
  84         u64 ident;
  85
  86         BUG_ON(!(vio->dr_state & VIO_DR_STATE_RXREG));
  87
  88         dr = &vio->drings[VIO_DRIVER_RX_RING];
  89         ident = dr->ident;
  90
  91         BUG_ON(!vio->desc_buf);
  92         kfree(vio->desc_buf);
  93         vio->desc_buf = NULL;
  94
  95         memset(dr, 0, sizeof(*dr));
  96         dr->ident = ident;
  97 }
  98
  99 void vio_link_state_change(struct vio_driver_state *vio, int event)
 100 {
 101         if (event == LDC_EVENT_UP) {
 102                 vio->hs_state = VIO_HS_INVALID;
 103
 104                 switch (vio->dev_class) {
 105                 case VDEV_NETWORK:
 106                 case VDEV_NETWORK_SWITCH:
 107                         vio->dr_state = (VIO_DR_STATE_TXREQ |
 108                                          VIO_DR_STATE_RXREQ);
 109                         break;
 110
 111                 case VDEV_DISK:
 112                         vio->dr_state = VIO_DR_STATE_TXREQ;
 113                         break;
 114                 case VDEV_DISK_SERVER:
 115                         vio->dr_state = VIO_DR_STATE_RXREQ;
 116                         break;
 117                 }
 118                 start_handshake(vio);
 119         } else if (event == LDC_EVENT_RESET) {
 120                 vio->hs_state = VIO_HS_INVALID;
 121
 122                 if (vio->dr_state & VIO_DR_STATE_RXREG)
 123                         flush_rx_dring(vio);
 124
 125                 vio->dr_state = 0x00;
 126                 memset(&vio->ver, 0, sizeof(vio->ver));
 127
 128                 ldc_disconnect(vio->lp);
 129         }
 130 }
 131 EXPORT_SYMBOL(vio_link_state_change);
 132
 133 static int handshake_failure(struct vio_driver_state *vio)
 134 {
 135         struct vio_dring_state *dr;
 136
 137         /* XXX Put policy here...  Perhaps start a timer to fire
 138          * XXX in 100 ms, which will bring the link up and retry
 139          * XXX the handshake.
 140          */
 141
 142         viodbg(HS, "HANDSHAKE FAILURE\n");
 143
 144         vio->dr_state &= ~(VIO_DR_STATE_TXREG |
 145                            VIO_DR_STATE_RXREG);
 146
 147         dr = &vio->drings[VIO_DRIVER_RX_RING];
 148         memset(dr, 0, sizeof(*dr));
 149
 150         kfree(vio->desc_buf);
 151         vio->desc_buf = NULL;
 152         vio->desc_buf_len = 0;
 153
 154         vio->hs_state = VIO_HS_INVALID;
 155
 156         return -ECONNRESET;
 157 }
 158
 159 static int process_unknown(struct vio_driver_state *vio, void *arg)
 160 {
 161         struct vio_msg_tag *pkt = arg;
 162
 163         viodbg(HS, "UNKNOWN CONTROL [%02x:%02x:%04x:%08x]\n",
 164                pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
 165
 166         printk(KERN_ERR "vio: ID[%lu] Resetting connection.\n",
 167                vio->vdev->channel_id);
 168
 169         ldc_disconnect(vio->lp);
 170
 171         return -ECONNRESET;
 172 }
 173
 174 static int send_dreg(struct vio_driver_state *vio)
 175 {
 176         struct vio_dring_state *dr = &vio->drings[VIO_DRIVER_TX_RING];
 177         union {
 178                 struct vio_dring_register pkt;
 179                 char all[sizeof(struct vio_dring_register) +
 180                          (sizeof(struct ldc_trans_cookie) *
 181                           dr->ncookies)];
 182         } u;
 183         int i;
 184
 185         memset(&u, 0, sizeof(u));
 186         init_tag(&u.pkt.tag, VIO_TYPE_CTRL, VIO_SUBTYPE_INFO, VIO_DRING_REG);
 187         u.pkt.dring_ident = 0;
 188         u.pkt.num_descr = dr->num_entries;
 189         u.pkt.descr_size = dr->entry_size;
 190         u.pkt.options = VIO_TX_DRING;
 191         u.pkt.num_cookies = dr->ncookies;
 192
 193         viodbg(HS, "SEND DRING_REG INFO ndesc[%u] dsz[%u] opt[0x%x] "
 194                "ncookies[%u]\n",
 195                u.pkt.num_descr, u.pkt.descr_size, u.pkt.options,
 196                u.pkt.num_cookies);
 197
 198         for (i = 0; i < dr->ncookies; i++) {
 199                 u.pkt.cookies[i] = dr->cookies[i];
 200
 201                 viodbg(HS, "DRING COOKIE(%d) [%016llx:%016llx]\n",
 202                        i,
 203                        (unsigned long long) u.pkt.cookies[i].cookie_addr,
 204                        (unsigned long long) u.pkt.cookies[i].cookie_size);
 205         }
 206
 207         return send_ctrl(vio, &u.pkt.tag, sizeof(u));
 208 }
 209
 210 static int send_rdx(struct vio_driver_state *vio)
 211 {
 212         struct vio_rdx pkt;
 213
 214         memset(&pkt, 0, sizeof(pkt));
 215
 216         init_tag(&pkt.tag, VIO_TYPE_CTRL, VIO_SUBTYPE_INFO, VIO_RDX);
 217
 218         viodbg(HS, "SEND RDX INFO\n");
 219
 220         return send_ctrl(vio, &pkt.tag, sizeof(pkt));
 221 }
 222
 223 static int send_attr(struct vio_driver_state *vio)
 224 {
 225         return vio->ops->send_attr(vio);
 226 }
 227
 228 static struct vio_version *find_by_major(struct vio_driver_state *vio,
 229                                          u16 major)
 230 {
 231         struct vio_version *ret = NULL;
 232         int i;
 233
 234         for (i = 0; i < vio->ver_table_entries; i++) {
 235                 struct vio_version *v = &vio->ver_table[i];
 236                 if (v->major <= major) {
 237                         ret = v;
 238                         break;
 239                 }
 240         }
 241         return ret;
 242 }
 243
 244 static int process_ver_info(struct vio_driver_state *vio,
 245                             struct vio_ver_info *pkt)
 246 {
 247         struct vio_version *vap;
 248         int err;
 249
 250         viodbg(HS, "GOT VERSION INFO maj[%u] min[%u] devclass[%u]\n",
 251                pkt->major, pkt->minor, pkt->dev_class);
 252
 253         if (vio->hs_state != VIO_HS_INVALID) {
 254                 /* XXX Perhaps invoke start_handshake? XXX */
 255                 memset(&vio->ver, 0, sizeof(vio->ver));
 256                 vio->hs_state = VIO_HS_INVALID;
 257         }
 258
 259         vap = find_by_major(vio, pkt->major);
 260
 261         vio->_peer_sid = pkt->tag.sid;
 262
 263         if (!vap) {
 264                 pkt->tag.stype = VIO_SUBTYPE_NACK;
 265                 pkt->major = 0;
 266                 pkt->minor = 0;
 267                 viodbg(HS, "SEND VERSION NACK maj[0] min[0]\n");
 268                 err = send_ctrl(vio, &pkt->tag, sizeof(*pkt));
 269         } else if (vap->major != pkt->major) {
 270                 pkt->tag.stype = VIO_SUBTYPE_NACK;
 271                 pkt->major = vap->major;
 272                 pkt->minor = vap->minor;
 273                 viodbg(HS, "SEND VERSION NACK maj[%u] min[%u]\n",
 274                        pkt->major, pkt->minor);
 275                 err = send_ctrl(vio, &pkt->tag, sizeof(*pkt));
 276         } else {
 277                 struct vio_version ver = {
 278                         .major = pkt->major,
 279                         .minor = pkt->minor,
 280                 };
 281                 if (ver.minor > vap->minor)
 282                         ver.minor = vap->minor;
 283                 pkt->minor = ver.minor;
 284                 pkt->tag.stype = VIO_SUBTYPE_ACK;
 285                 viodbg(HS, "SEND VERSION ACK maj[%u] min[%u]\n",
 286                        pkt->major, pkt->minor);
 287                 err = send_ctrl(vio, &pkt->tag, sizeof(*pkt));
 288                 if (err > 0) {
 289                         vio->ver = ver;
 290                         vio->hs_state = VIO_HS_GOTVERS;
 291                 }
 292         }
 293         if (err < 0)
 294                 return handshake_failure(vio);
 295
 296         return 0;
 297 }
 298
 299 static int process_ver_ack(struct vio_driver_state *vio,
 300                            struct vio_ver_info *pkt)
 301 {
 302         viodbg(HS, "GOT VERSION ACK maj[%u] min[%u] devclass[%u]\n",
 303                pkt->major, pkt->minor, pkt->dev_class);
 304
 305         if (vio->hs_state & VIO_HS_GOTVERS) {
 306                 if (vio->ver.major != pkt->major ||
 307                     vio->ver.minor != pkt->minor) {
 308                         pkt->tag.stype = VIO_SUBTYPE_NACK;
 309                         (void) send_ctrl(vio, &pkt->tag, sizeof(*pkt));
 310                         return handshake_failure(vio);
 311                 }
 312         } else {
 313                 vio->ver.major = pkt->major;
 314                 vio->ver.minor = pkt->minor;
 315                 vio->hs_state = VIO_HS_GOTVERS;
 316         }
 317
 318         switch (vio->dev_class) {
 319         case VDEV_NETWORK:
 320         case VDEV_DISK:
 321                 if (send_attr(vio) < 0)
 322                         return handshake_failure(vio);
 323                 break;
 324
 325         default:
 326                 break;
 327         }
 328
 329         return 0;
 330 }
 331
 332 static int process_ver_nack(struct vio_driver_state *vio,
 333                             struct vio_ver_info *pkt)
 334 {
 335         struct vio_version *nver;
 336
 337         viodbg(HS, "GOT VERSION NACK maj[%u] min[%u] devclass[%u]\n",
 338                pkt->major, pkt->minor, pkt->dev_class);
 339
 340         if (pkt->major == 0 && pkt->minor == 0)
 341                 return handshake_failure(vio);
 342         nver = find_by_major(vio, pkt->major);
 343         if (!nver)
 344                 return handshake_failure(vio);
 345
 346         if (send_version(vio, nver->major, nver->minor) < 0)
 347                 return handshake_failure(vio);
 348
 349         return 0;
 350 }
 351
 352 static int process_ver(struct vio_driver_state *vio, struct vio_ver_info *pkt)
 353 {
 354         switch (pkt->tag.stype) {
 355         case VIO_SUBTYPE_INFO:
 356                 return process_ver_info(vio, pkt);
 357
 358         case VIO_SUBTYPE_ACK:
 359                 return process_ver_ack(vio, pkt);
 360
 361         case VIO_SUBTYPE_NACK:
 362                 return process_ver_nack(vio, pkt);
 363
 364         default:
 365                 return handshake_failure(vio);
 366         };
 367 }
 368
 369 static int process_attr(struct vio_driver_state *vio, void *pkt)
 370 {
 371         int err;
 372
 373         if (!(vio->hs_state & VIO_HS_GOTVERS))
 374                 return handshake_failure(vio);
 375
 376         err = vio->ops->handle_attr(vio, pkt);
 377         if (err < 0) {
 378                 return handshake_failure(vio);
 379         } else {
 380                 vio->hs_state |= VIO_HS_GOT_ATTR;
 381
 382                 if ((vio->dr_state & VIO_DR_STATE_TXREQ) &&
 383                     !(vio->hs_state & VIO_HS_SENT_DREG)) {
 384                         if (send_dreg(vio) < 0)
 385                                 return handshake_failure(vio);
 386
 387                         vio->hs_state |= VIO_HS_SENT_DREG;
 388                 }
 389         }
 390         return 0;
 391 }
 392
 393 static int all_drings_registered(struct vio_driver_state *vio)
 394 {
 395         int need_rx, need_tx;
 396
 397         need_rx = (vio->dr_state & VIO_DR_STATE_RXREQ);
 398         need_tx = (vio->dr_state & VIO_DR_STATE_TXREQ);
 399
 400         if (need_rx &&
 401             !(vio->dr_state & VIO_DR_STATE_RXREG))
 402                 return 0;
 403
 404         if (need_tx &&
 405             !(vio->dr_state & VIO_DR_STATE_TXREG))
 406                 return 0;
 407
 408         return 1;
 409 }
 410
 411 static int process_dreg_info(struct vio_driver_state *vio,
 412                              struct vio_dring_register *pkt)
 413 {
 414         struct vio_dring_state *dr;
 415         int i, len;
 416
 417         viodbg(HS, "GOT DRING_REG INFO ident[%llx] "
 418                "ndesc[%u] dsz[%u] opt[0x%x] ncookies[%u]\n",
 419                (unsigned long long) pkt->dring_ident,
 420                pkt->num_descr, pkt->descr_size, pkt->options,
 421                pkt->num_cookies);
 422
 423         if (!(vio->dr_state & VIO_DR_STATE_RXREQ))
 424                 goto send_nack;
 425
 426         if (vio->dr_state & VIO_DR_STATE_RXREG)
 427                 goto send_nack;
 428
 429         BUG_ON(vio->desc_buf);
 430
 431         vio->desc_buf = kzalloc(pkt->descr_size, GFP_ATOMIC);
 432         if (!vio->desc_buf)
 433                 goto send_nack;
 434
 435         vio->desc_buf_len = pkt->descr_size;
 436
 437         dr = &vio->drings[VIO_DRIVER_RX_RING];
 438
 439         dr->num_entries = pkt->num_descr;
 440         dr->entry_size = pkt->descr_size;
 441         dr->ncookies = pkt->num_cookies;
 442         for (i = 0; i < dr->ncookies; i++) {
 443                 dr->cookies[i] = pkt->cookies[i];
 444
 445                 viodbg(HS, "DRING COOKIE(%d) [%016llx:%016llx]\n",
 446                        i,
 447                        (unsigned long long)
 448                        pkt->cookies[i].cookie_addr,
 449                        (unsigned long long)
 450                        pkt->cookies[i].cookie_size);
 451         }
 452
 453         pkt->tag.stype = VIO_SUBTYPE_ACK;
 454         pkt->dring_ident = ++dr->ident;
 455
 456         viodbg(HS, "SEND DRING_REG ACK ident[%llx]\n",
 457                (unsigned long long) pkt->dring_ident);
 458
 459         len = (sizeof(*pkt) +
 460                (dr->ncookies * sizeof(struct ldc_trans_cookie)));
 461         if (send_ctrl(vio, &pkt->tag, len) < 0)
 462                 goto send_nack;
 463
 464         vio->dr_state |= VIO_DR_STATE_RXREG;
 465
 466         return 0;
 467
 468 send_nack:
 469         pkt->tag.stype = VIO_SUBTYPE_NACK;
 470         viodbg(HS, "SEND DRING_REG NACK\n");
 471         (void) send_ctrl(vio, &pkt->tag, sizeof(*pkt));
 472
 473         return handshake_failure(vio);
 474 }
 475
 476 static int process_dreg_ack(struct vio_driver_state *vio,
 477                             struct vio_dring_register *pkt)
 478 {
 479         struct vio_dring_state *dr;
 480
 481         viodbg(HS, "GOT DRING_REG ACK ident[%llx] "
 482                "ndesc[%u] dsz[%u] opt[0x%x] ncookies[%u]\n",
 483                (unsigned long long) pkt->dring_ident,
 484                pkt->num_descr, pkt->descr_size, pkt->options,
 485                pkt->num_cookies);
 486
 487         dr = &vio->drings[VIO_DRIVER_TX_RING];
 488
 489         if (!(vio->dr_state & VIO_DR_STATE_TXREQ))
 490                 return handshake_failure(vio);
 491
 492         dr->ident = pkt->dring_ident;
 493         vio->dr_state |= VIO_DR_STATE_TXREG;
 494
 495         if (all_drings_registered(vio)) {
 496                 if (send_rdx(vio) < 0)
 497                         return handshake_failure(vio);
 498                 vio->hs_state = VIO_HS_SENT_RDX;
 499         }
 500         return 0;
 501 }
 502
 503 static int process_dreg_nack(struct vio_driver_state *vio,
 504                              struct vio_dring_register *pkt)
 505 {
 506         viodbg(HS, "GOT DRING_REG NACK ident[%llx] "
 507                "ndesc[%u] dsz[%u] opt[0x%x] ncookies[%u]\n",
 508                (unsigned long long) pkt->dring_ident,
 509                pkt->num_descr, pkt->descr_size, pkt->options,
 510                pkt->num_cookies);
 511
 512         return handshake_failure(vio);
 513 }
 514
 515 static int process_dreg(struct vio_driver_state *vio,
 516                         struct vio_dring_register *pkt)
 517 {
 518         if (!(vio->hs_state & VIO_HS_GOTVERS))
 519                 return handshake_failure(vio);
 520
 521         switch (pkt->tag.stype) {
 522         case VIO_SUBTYPE_INFO:
 523                 return process_dreg_info(vio, pkt);
 524
 525         case VIO_SUBTYPE_ACK:
 526                 return process_dreg_ack(vio, pkt);
 527
 528         case VIO_SUBTYPE_NACK:
 529                 return process_dreg_nack(vio, pkt);
 530
 531         default:
 532                 return handshake_failure(vio);
 533         }
 534 }
 535
 536 static int process_dunreg(struct vio_driver_state *vio,
 537                           struct vio_dring_unregister *pkt)
 538 {
 539         struct vio_dring_state *dr = &vio->drings[VIO_DRIVER_RX_RING];
 540
 541         viodbg(HS, "GOT DRING_UNREG\n");
 542
 543         if (pkt->dring_ident != dr->ident)
 544                 return 0;
 545
 546         vio->dr_state &= ~VIO_DR_STATE_RXREG;
 547
 548         memset(dr, 0, sizeof(*dr));
 549
 550         kfree(vio->desc_buf);
 551         vio->desc_buf = NULL;
 552         vio->desc_buf_len = 0;
 553
 554         return 0;
 555 }
 556
 557 static int process_rdx_info(struct vio_driver_state *vio, struct vio_rdx *pkt)
 558 {
 559         viodbg(HS, "GOT RDX INFO\n");
 560
 561         pkt->tag.stype = VIO_SUBTYPE_ACK;
 562         viodbg(HS, "SEND RDX ACK\n");
 563         if (send_ctrl(vio, &pkt->tag, sizeof(*pkt)) < 0)
 564                 return handshake_failure(vio);
 565
 566         vio->hs_state |= VIO_HS_SENT_RDX_ACK;
 567         return 0;
 568 }
 569
 570 static int process_rdx_ack(struct vio_driver_state *vio, struct vio_rdx *pkt)
 571 {
 572         viodbg(HS, "GOT RDX ACK\n");
 573
 574         if (!(vio->hs_state & VIO_HS_SENT_RDX))
 575                 return handshake_failure(vio);
 576
 577         vio->hs_state |= VIO_HS_GOT_RDX_ACK;
 578         return 0;
 579 }
 580
 581 static int process_rdx_nack(struct vio_driver_state *vio, struct vio_rdx *pkt)
 582 {
 583         viodbg(HS, "GOT RDX NACK\n");
 584
 585         return handshake_failure(vio);
 586 }
 587
 588 static int process_rdx(struct vio_driver_state *vio, struct vio_rdx *pkt)
 589 {
 590         if (!all_drings_registered(vio))
 591                 handshake_failure(vio);
 592
 593         switch (pkt->tag.stype) {
 594         case VIO_SUBTYPE_INFO:
 595                 return process_rdx_info(vio, pkt);
 596
 597         case VIO_SUBTYPE_ACK:
 598                 return process_rdx_ack(vio, pkt);
 599
 600         case VIO_SUBTYPE_NACK:
 601                 return process_rdx_nack(vio, pkt);
 602
 603         default:
 604                 return handshake_failure(vio);
 605         }
 606 }
 607
 608 int vio_control_pkt_engine(struct vio_driver_state *vio, void *pkt)
 609 {
 610         struct vio_msg_tag *tag = pkt;
 611         u8 prev_state = vio->hs_state;
 612         int err;
 613
 614         switch (tag->stype_env) {
 615         case VIO_VER_INFO:
 616                 err = process_ver(vio, pkt);
 617                 break;
 618
 619         case VIO_ATTR_INFO:
 620                 err = process_attr(vio, pkt);
 621                 break;
 622
 623         case VIO_DRING_REG:
 624                 err = process_dreg(vio, pkt);
 625                 break;
 626
 627         case VIO_DRING_UNREG:
 628                 err = process_dunreg(vio, pkt);
 629                 break;
 630
 631         case VIO_RDX:
 632                 err = process_rdx(vio, pkt);
 633                 break;
 634
 635         default:
 636                 err = process_unknown(vio, pkt);
 637                 break;
 638         }
 639         if (!err &&
 640             vio->hs_state != prev_state &&
 641             (vio->hs_state & VIO_HS_COMPLETE))
 642                 vio->ops->handshake_complete(vio);
 643
 644         return err;
 645 }
 646 EXPORT_SYMBOL(vio_control_pkt_engine);
 647
 648 void vio_conn_reset(struct vio_driver_state *vio)
 649 {
 650 }
 651 EXPORT_SYMBOL(vio_conn_reset);
 652
 653 /* The issue is that the Solaris virtual disk server just mirrors the
 654  * SID values it gets from the client peer.  So we work around that
 655  * here in vio_{validate,send}_sid() so that the drivers don't need
 656  * to be aware of this crap.
 657  */
 658 int vio_validate_sid(struct vio_driver_state *vio, struct vio_msg_tag *tp)
 659 {
 660         u32 sid;
 661
 662         /* Always let VERSION+INFO packets through unchecked, they
 663          * define the new SID.
 664          */
 665         if (tp->type == VIO_TYPE_CTRL &&
 666             tp->stype == VIO_SUBTYPE_INFO &&
 667             tp->stype_env == VIO_VER_INFO)
 668                 return 0;
 669
 670         /* Ok, now figure out which SID to use.  */
 671         switch (vio->dev_class) {
 672         case VDEV_NETWORK:
 673         case VDEV_NETWORK_SWITCH:
 674         case VDEV_DISK_SERVER:
 675         default:
 676                 sid = vio->_peer_sid;
 677                 break;
 678
 679         case VDEV_DISK:
 680                 sid = vio->_local_sid;
 681                 break;
 682         }
 683
 684         if (sid == tp->sid)
 685                 return 0;
 686         viodbg(DATA, "BAD SID tag->sid[%08x] peer_sid[%08x] local_sid[%08x]\n",
 687                tp->sid, vio->_peer_sid, vio->_local_sid);
 688         return -EINVAL;
 689 }
 690 EXPORT_SYMBOL(vio_validate_sid);
 691
 692 u32 vio_send_sid(struct vio_driver_state *vio)
 693 {
 694         switch (vio->dev_class) {
 695         case VDEV_NETWORK:
 696         case VDEV_NETWORK_SWITCH:
 697         case VDEV_DISK:
 698         default:
 699                 return vio->_local_sid;
 700
 701         case VDEV_DISK_SERVER:
 702                 return vio->_peer_sid;
 703         }
 704 }
 705 EXPORT_SYMBOL(vio_send_sid);
 706
 707 int vio_ldc_alloc(struct vio_driver_state *vio,
 708                          struct ldc_channel_config *base_cfg,
 709                          void *event_arg)
 710 {
 711         struct ldc_channel_config cfg = *base_cfg;
 712         struct ldc_channel *lp;
 713
 714         cfg.tx_irq = vio->vdev->tx_irq;
 715         cfg.rx_irq = vio->vdev->rx_irq;
 716
 717         lp = ldc_alloc(vio->vdev->channel_id, &cfg, event_arg);
 718         if (IS_ERR(lp))
 719                 return PTR_ERR(lp);
 720
 721         vio->lp = lp;
 722
 723         return 0;
 724 }
 725 EXPORT_SYMBOL(vio_ldc_alloc);
 726
 727 void vio_ldc_free(struct vio_driver_state *vio)
 728 {
 729         ldc_free(vio->lp);
 730         vio->lp = NULL;
 731
 732         kfree(vio->desc_buf);
 733         vio->desc_buf = NULL;
 734         vio->desc_buf_len = 0;
 735 }
 736 EXPORT_SYMBOL(vio_ldc_free);
 737
 738 void vio_port_up(struct vio_driver_state *vio)
 739 {
 740         unsigned long flags;
 741         int err, state;
 742
 743         spin_lock_irqsave(&vio->lock, flags);
 744
 745         state = ldc_state(vio->lp);
 746
 747         err = 0;
 748         if (state == LDC_STATE_INIT) {
 749                 err = ldc_bind(vio->lp, vio->name);
 750                 if (err)
 751                         printk(KERN_WARNING "%s: Port %lu bind failed, "
 752                                "err=%d\n",
 753                                vio->name, vio->vdev->channel_id, err);
 754         }
 755
 756         if (!err) {
 757                 err = ldc_connect(vio->lp);
 758                 if (err)
 759                         printk(KERN_WARNING "%s: Port %lu connect failed, "
 760                                "err=%d\n",
 761                                vio->name, vio->vdev->channel_id, err);
 762         }
 763         if (err) {
 764                 unsigned long expires = jiffies + HZ;
 765
 766                 expires = round_jiffies(expires);
 767                 mod_timer(&vio->timer, expires);
 768         }
 769
 770         spin_unlock_irqrestore(&vio->lock, flags);
 771 }
 772 EXPORT_SYMBOL(vio_port_up);
 773
 774 static void vio_port_timer(unsigned long _arg)
 775 {
 776         struct vio_driver_state *vio = (struct vio_driver_state *) _arg;
 777
 778         vio_port_up(vio);
 779 }
 780
 781 int vio_driver_init(struct vio_driver_state *vio, struct vio_dev *vdev,
 782                     u8 dev_class, struct vio_version *ver_table,
 783                     int ver_table_size, struct vio_driver_ops *ops,
 784                     char *name)
 785 {
 786         switch (dev_class) {
 787         case VDEV_NETWORK:
 788         case VDEV_NETWORK_SWITCH:
 789         case VDEV_DISK:
 790         case VDEV_DISK_SERVER:
 791                 break;
 792
 793         default:
 794                 return -EINVAL;
 795         }
 796
 797         if (!ops->send_attr ||
 798             !ops->handle_attr ||
 799             !ops->handshake_complete)
 800                 return -EINVAL;
 801
 802         if (!ver_table || ver_table_size < 0)
 803                 return -EINVAL;
 804
 805         if (!name)
 806                 return -EINVAL;
 807
 808         spin_lock_init(&vio->lock);
 809
 810         vio->name = name;
 811
 812         vio->dev_class = dev_class;
 813         vio->vdev = vdev;
 814
 815         vio->ver_table = ver_table;
 816         vio->ver_table_entries = ver_table_size;
 817
 818         vio->ops = ops;
 819
 820         setup_timer(&vio->timer, vio_port_timer, (unsigned long) vio);
 821
 822         return 0;
 823 }
 824 EXPORT_SYMBOL(vio_driver_init);