git.oblomov.eu Git - linux-2.6/blob - drivers/block/sunvdc.c

   1 /* sunvdc.c: Sun LDOM Virtual Disk Client.
   2  *
   3  * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
   4  */
   5
   6 #include <linux/module.h>
   7 #include <linux/kernel.h>
   8 #include <linux/types.h>
   9 #include <linux/blkdev.h>
  10 #include <linux/hdreg.h>
  11 #include <linux/genhd.h>
  12 #include <linux/slab.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/completion.h>
  15 #include <linux/delay.h>
  16 #include <linux/init.h>
  17 #include <linux/list.h>
  18
  19 #include <asm/vio.h>
  20 #include <asm/ldc.h>
  21
  22 #define DRV_MODULE_NAME         "sunvdc"
  23 #define PFX DRV_MODULE_NAME     ": "
  24 #define DRV_MODULE_VERSION      "1.0"
  25 #define DRV_MODULE_RELDATE      "June 25, 2007"
  26
  27 static char version[] __devinitdata =
  28         DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
  29 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
  30 MODULE_DESCRIPTION("Sun LDOM virtual disk client driver");
  31 MODULE_LICENSE("GPL");
  32 MODULE_VERSION(DRV_MODULE_VERSION);
  33
  34 #define VDC_TX_RING_SIZE        256
  35
  36 #define WAITING_FOR_LINK_UP     0x01
  37 #define WAITING_FOR_TX_SPACE    0x02
  38 #define WAITING_FOR_GEN_CMD     0x04
  39 #define WAITING_FOR_ANY         -1
  40
  41 struct vdc_req_entry {
  42         struct request          *req;
  43 };
  44
  45 struct vdc_port {
  46         struct vio_driver_state vio;
  47
  48         struct gendisk          *disk;
  49
  50         struct vdc_completion   *cmp;
  51
  52         u64                     req_id;
  53         u64                     seq;
  54         struct vdc_req_entry    rq_arr[VDC_TX_RING_SIZE];
  55
  56         unsigned long           ring_cookies;
  57
  58         u64                     max_xfer_size;
  59         u32                     vdisk_block_size;
  60
  61         /* The server fills these in for us in the disk attribute
  62          * ACK packet.
  63          */
  64         u64                     operations;
  65         u32                     vdisk_size;
  66         u8                      vdisk_type;
  67
  68         char                    disk_name[32];
  69
  70         struct vio_disk_geom    geom;
  71         struct vio_disk_vtoc    label;
  72 };
  73
  74 static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
  75 {
  76         return container_of(vio, struct vdc_port, vio);
  77 }
  78
  79 /* Ordered from largest major to lowest */
  80 static struct vio_version vdc_versions[] = {
  81         { .major = 1, .minor = 0 },
  82 };
  83
  84 #define VDCBLK_NAME     "vdisk"
  85 static int vdc_major;
  86 #define PARTITION_SHIFT 3
  87
  88 static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr)
  89 {
  90         return vio_dring_avail(dr, VDC_TX_RING_SIZE);
  91 }
  92
  93 static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo)
  94 {
  95         struct gendisk *disk = bdev->bd_disk;
  96         struct vdc_port *port = disk->private_data;
  97
  98         geo->heads = (u8) port->geom.num_hd;
  99         geo->sectors = (u8) port->geom.num_sec;
 100         geo->cylinders = port->geom.num_cyl;
 101
 102         return 0;
 103 }
 104
 105 static struct block_device_operations vdc_fops = {
 106         .owner          = THIS_MODULE,
 107         .getgeo         = vdc_getgeo,
 108 };
 109
 110 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)
 111 {
 112         if (vio->cmp &&
 113             (waiting_for == -1 ||
 114              vio->cmp->waiting_for == waiting_for)) {
 115                 vio->cmp->err = err;
 116                 complete(&vio->cmp->com);
 117                 vio->cmp = NULL;
 118         }
 119 }
 120
 121 static void vdc_handshake_complete(struct vio_driver_state *vio)
 122 {
 123         vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
 124 }
 125
 126 static int vdc_handle_unknown(struct vdc_port *port, void *arg)
 127 {
 128         struct vio_msg_tag *pkt = arg;
 129
 130         printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n",
 131                pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
 132         printk(KERN_ERR PFX "Resetting connection.\n");
 133
 134         ldc_disconnect(port->vio.lp);
 135
 136         return -ECONNRESET;
 137 }
 138
 139 static int vdc_send_attr(struct vio_driver_state *vio)
 140 {
 141         struct vdc_port *port = to_vdc_port(vio);
 142         struct vio_disk_attr_info pkt;
 143
 144         memset(&pkt, 0, sizeof(pkt));
 145
 146         pkt.tag.type = VIO_TYPE_CTRL;
 147         pkt.tag.stype = VIO_SUBTYPE_INFO;
 148         pkt.tag.stype_env = VIO_ATTR_INFO;
 149         pkt.tag.sid = vio_send_sid(vio);
 150
 151         pkt.xfer_mode = VIO_DRING_MODE;
 152         pkt.vdisk_block_size = port->vdisk_block_size;
 153         pkt.max_xfer_size = port->max_xfer_size;
 154
 155         viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%lu]\n",
 156                pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size);
 157
 158         return vio_ldc_send(&port->vio, &pkt, sizeof(pkt));
 159 }
 160
 161 static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
 162 {
 163         struct vdc_port *port = to_vdc_port(vio);
 164         struct vio_disk_attr_info *pkt = arg;
 165
 166         viodbg(HS, "GOT ATTR stype[0x%x] ops[%lx] disk_size[%lu] disk_type[%x] "
 167                "xfer_mode[0x%x] blksz[%u] max_xfer[%lu]\n",
 168                pkt->tag.stype, pkt->operations,
 169                pkt->vdisk_size, pkt->vdisk_type,
 170                pkt->xfer_mode, pkt->vdisk_block_size,
 171                pkt->max_xfer_size);
 172
 173         if (pkt->tag.stype == VIO_SUBTYPE_ACK) {
 174                 switch (pkt->vdisk_type) {
 175                 case VD_DISK_TYPE_DISK:
 176                 case VD_DISK_TYPE_SLICE:
 177                         break;
 178
 179                 default:
 180                         printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n",
 181                                vio->name, pkt->vdisk_type);
 182                         return -ECONNRESET;
 183                 }
 184
 185                 if (pkt->vdisk_block_size > port->vdisk_block_size) {
 186                         printk(KERN_ERR PFX "%s: BLOCK size increased "
 187                                "%u --> %u\n",
 188                                vio->name,
 189                                port->vdisk_block_size, pkt->vdisk_block_size);
 190                         return -ECONNRESET;
 191                 }
 192
 193                 port->operations = pkt->operations;
 194                 port->vdisk_size = pkt->vdisk_size;
 195                 port->vdisk_type = pkt->vdisk_type;
 196                 if (pkt->max_xfer_size < port->max_xfer_size)
 197                         port->max_xfer_size = pkt->max_xfer_size;
 198                 port->vdisk_block_size = pkt->vdisk_block_size;
 199                 return 0;
 200         } else {
 201                 printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name);
 202
 203                 return -ECONNRESET;
 204         }
 205 }
 206
 207 static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc)
 208 {
 209         int err = desc->status;
 210
 211         vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD);
 212 }
 213
 214 static void vdc_end_request(struct request *req, int uptodate, int num_sectors)
 215 {
 216         if (end_that_request_first(req, uptodate, num_sectors))
 217                 return;
 218         add_disk_randomness(req->rq_disk);
 219         end_that_request_last(req, uptodate);
 220 }
 221
 222 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
 223                         unsigned int index)
 224 {
 225         struct vio_disk_desc *desc = vio_dring_entry(dr, index);
 226         struct vdc_req_entry *rqe = &port->rq_arr[index];
 227         struct request *req;
 228
 229         if (unlikely(desc->hdr.state != VIO_DESC_DONE))
 230                 return;
 231
 232         ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
 233         desc->hdr.state = VIO_DESC_FREE;
 234         dr->cons = (index + 1) & (VDC_TX_RING_SIZE - 1);
 235
 236         req = rqe->req;
 237         if (req == NULL) {
 238                 vdc_end_special(port, desc);
 239                 return;
 240         }
 241
 242         rqe->req = NULL;
 243
 244         vdc_end_request(req, !desc->status, desc->size >> 9);
 245
 246         if (blk_queue_stopped(port->disk->queue))
 247                 blk_start_queue(port->disk->queue);
 248 }
 249
 250 static int vdc_ack(struct vdc_port *port, void *msgbuf)
 251 {
 252         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 253         struct vio_dring_data *pkt = msgbuf;
 254
 255         if (unlikely(pkt->dring_ident != dr->ident ||
 256                      pkt->start_idx != pkt->end_idx ||
 257                      pkt->start_idx >= VDC_TX_RING_SIZE))
 258                 return 0;
 259
 260         vdc_end_one(port, dr, pkt->start_idx);
 261
 262         return 0;
 263 }
 264
 265 static int vdc_nack(struct vdc_port *port, void *msgbuf)
 266 {
 267         /* XXX Implement me XXX */
 268         return 0;
 269 }
 270
 271 static void vdc_event(void *arg, int event)
 272 {
 273         struct vdc_port *port = arg;
 274         struct vio_driver_state *vio = &port->vio;
 275         unsigned long flags;
 276         int err;
 277
 278         spin_lock_irqsave(&vio->lock, flags);
 279
 280         if (unlikely(event == LDC_EVENT_RESET ||
 281                      event == LDC_EVENT_UP)) {
 282                 vio_link_state_change(vio, event);
 283                 spin_unlock_irqrestore(&vio->lock, flags);
 284                 return;
 285         }
 286
 287         if (unlikely(event != LDC_EVENT_DATA_READY)) {
 288                 printk(KERN_WARNING PFX "Unexpected LDC event %d\n", event);
 289                 spin_unlock_irqrestore(&vio->lock, flags);
 290                 return;
 291         }
 292
 293         err = 0;
 294         while (1) {
 295                 union {
 296                         struct vio_msg_tag tag;
 297                         u64 raw[8];
 298                 } msgbuf;
 299
 300                 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
 301                 if (unlikely(err < 0)) {
 302                         if (err == -ECONNRESET)
 303                                 vio_conn_reset(vio);
 304                         break;
 305                 }
 306                 if (err == 0)
 307                         break;
 308                 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
 309                        msgbuf.tag.type,
 310                        msgbuf.tag.stype,
 311                        msgbuf.tag.stype_env,
 312                        msgbuf.tag.sid);
 313                 err = vio_validate_sid(vio, &msgbuf.tag);
 314                 if (err < 0)
 315                         break;
 316
 317                 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
 318                         if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
 319                                 err = vdc_ack(port, &msgbuf);
 320                         else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
 321                                 err = vdc_nack(port, &msgbuf);
 322                         else
 323                                 err = vdc_handle_unknown(port, &msgbuf);
 324                 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
 325                         err = vio_control_pkt_engine(vio, &msgbuf);
 326                 } else {
 327                         err = vdc_handle_unknown(port, &msgbuf);
 328                 }
 329                 if (err < 0)
 330                         break;
 331         }
 332         if (err < 0)
 333                 vdc_finish(&port->vio, err, WAITING_FOR_ANY);
 334         spin_unlock_irqrestore(&vio->lock, flags);
 335 }
 336
 337 static int __vdc_tx_trigger(struct vdc_port *port)
 338 {
 339         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 340         struct vio_dring_data hdr = {
 341                 .tag = {
 342                         .type           = VIO_TYPE_DATA,
 343                         .stype          = VIO_SUBTYPE_INFO,
 344                         .stype_env      = VIO_DRING_DATA,
 345                         .sid            = vio_send_sid(&port->vio),
 346                 },
 347                 .dring_ident            = dr->ident,
 348                 .start_idx              = dr->prod,
 349                 .end_idx                = dr->prod,
 350         };
 351         int err, delay;
 352
 353         hdr.seq = dr->snd_nxt;
 354         delay = 1;
 355         do {
 356                 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
 357                 if (err > 0) {
 358                         dr->snd_nxt++;
 359                         break;
 360                 }
 361                 udelay(delay);
 362                 if ((delay <<= 1) > 128)
 363                         delay = 128;
 364         } while (err == -EAGAIN);
 365
 366         return err;
 367 }
 368
 369 static int __send_request(struct request *req)
 370 {
 371         struct vdc_port *port = req->rq_disk->private_data;
 372         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 373         struct scatterlist sg[port->ring_cookies];
 374         struct vdc_req_entry *rqe;
 375         struct vio_disk_desc *desc;
 376         unsigned int map_perm;
 377         int nsg, err, i;
 378         u64 len;
 379         u8 op;
 380
 381         map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 382
 383         if (rq_data_dir(req) == READ) {
 384                 map_perm |= LDC_MAP_W;
 385                 op = VD_OP_BREAD;
 386         } else {
 387                 map_perm |= LDC_MAP_R;
 388                 op = VD_OP_BWRITE;
 389         }
 390
 391         nsg = blk_rq_map_sg(req->q, req, sg);
 392
 393         len = 0;
 394         for (i = 0; i < nsg; i++)
 395                 len += sg[i].length;
 396
 397         if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
 398                 blk_stop_queue(port->disk->queue);
 399                 err = -ENOMEM;
 400                 goto out;
 401         }
 402
 403         desc = vio_dring_cur(dr);
 404
 405         err = ldc_map_sg(port->vio.lp, sg, nsg,
 406                          desc->cookies, port->ring_cookies,
 407                          map_perm);
 408         if (err < 0) {
 409                 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
 410                 return err;
 411         }
 412
 413         rqe = &port->rq_arr[dr->prod];
 414         rqe->req = req;
 415
 416         desc->hdr.ack = VIO_ACK_ENABLE;
 417         desc->req_id = port->req_id;
 418         desc->operation = op;
 419         if (port->vdisk_type == VD_DISK_TYPE_DISK) {
 420                 desc->slice = 0xff;
 421         } else {
 422                 desc->slice = 0;
 423         }
 424         desc->status = ~0;
 425         desc->offset = (req->sector << 9) / port->vdisk_block_size;
 426         desc->size = len;
 427         desc->ncookies = err;
 428
 429         /* This has to be a non-SMP write barrier because we are writing
 430          * to memory which is shared with the peer LDOM.
 431          */
 432         wmb();
 433         desc->hdr.state = VIO_DESC_READY;
 434
 435         err = __vdc_tx_trigger(port);
 436         if (err < 0) {
 437                 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
 438         } else {
 439                 port->req_id++;
 440                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
 441         }
 442 out:
 443
 444         return err;
 445 }
 446
 447 static void do_vdc_request(struct request_queue *q)
 448 {
 449         while (1) {
 450                 struct request *req = elv_next_request(q);
 451
 452                 if (!req)
 453                         break;
 454
 455                 blkdev_dequeue_request(req);
 456                 if (__send_request(req) < 0)
 457                         vdc_end_request(req, 0, req->hard_nr_sectors);
 458         }
 459 }
 460
 461 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
 462 {
 463         struct vio_dring_state *dr;
 464         struct vio_completion comp;
 465         struct vio_disk_desc *desc;
 466         unsigned int map_perm;
 467         unsigned long flags;
 468         int op_len, err;
 469         void *req_buf;
 470
 471         if (!(((u64)1 << ((u64)op - 1)) & port->operations))
 472                 return -EOPNOTSUPP;
 473
 474         switch (op) {
 475         case VD_OP_BREAD:
 476         case VD_OP_BWRITE:
 477         default:
 478                 return -EINVAL;
 479
 480         case VD_OP_FLUSH:
 481                 op_len = 0;
 482                 map_perm = 0;
 483                 break;
 484
 485         case VD_OP_GET_WCE:
 486                 op_len = sizeof(u32);
 487                 map_perm = LDC_MAP_W;
 488                 break;
 489
 490         case VD_OP_SET_WCE:
 491                 op_len = sizeof(u32);
 492                 map_perm = LDC_MAP_R;
 493                 break;
 494
 495         case VD_OP_GET_VTOC:
 496                 op_len = sizeof(struct vio_disk_vtoc);
 497                 map_perm = LDC_MAP_W;
 498                 break;
 499
 500         case VD_OP_SET_VTOC:
 501                 op_len = sizeof(struct vio_disk_vtoc);
 502                 map_perm = LDC_MAP_R;
 503                 break;
 504
 505         case VD_OP_GET_DISKGEOM:
 506                 op_len = sizeof(struct vio_disk_geom);
 507                 map_perm = LDC_MAP_W;
 508                 break;
 509
 510         case VD_OP_SET_DISKGEOM:
 511                 op_len = sizeof(struct vio_disk_geom);
 512                 map_perm = LDC_MAP_R;
 513                 break;
 514
 515         case VD_OP_SCSICMD:
 516                 op_len = 16;
 517                 map_perm = LDC_MAP_RW;
 518                 break;
 519
 520         case VD_OP_GET_DEVID:
 521                 op_len = sizeof(struct vio_disk_devid);
 522                 map_perm = LDC_MAP_W;
 523                 break;
 524
 525         case VD_OP_GET_EFI:
 526         case VD_OP_SET_EFI:
 527                 return -EOPNOTSUPP;
 528                 break;
 529         };
 530
 531         map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 532
 533         op_len = (op_len + 7) & ~7;
 534         req_buf = kzalloc(op_len, GFP_KERNEL);
 535         if (!req_buf)
 536                 return -ENOMEM;
 537
 538         if (len > op_len)
 539                 len = op_len;
 540
 541         if (map_perm & LDC_MAP_R)
 542                 memcpy(req_buf, buf, len);
 543
 544         spin_lock_irqsave(&port->vio.lock, flags);
 545
 546         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 547
 548         /* XXX If we want to use this code generically we have to
 549          * XXX handle TX ring exhaustion etc.
 550          */
 551         desc = vio_dring_cur(dr);
 552
 553         err = ldc_map_single(port->vio.lp, req_buf, op_len,
 554                              desc->cookies, port->ring_cookies,
 555                              map_perm);
 556         if (err < 0) {
 557                 spin_unlock_irqrestore(&port->vio.lock, flags);
 558                 kfree(req_buf);
 559                 return err;
 560         }
 561
 562         init_completion(&comp.com);
 563         comp.waiting_for = WAITING_FOR_GEN_CMD;
 564         port->vio.cmp = &comp;
 565
 566         desc->hdr.ack = VIO_ACK_ENABLE;
 567         desc->req_id = port->req_id;
 568         desc->operation = op;
 569         desc->slice = 0;
 570         desc->status = ~0;
 571         desc->offset = 0;
 572         desc->size = op_len;
 573         desc->ncookies = err;
 574
 575         /* This has to be a non-SMP write barrier because we are writing
 576          * to memory which is shared with the peer LDOM.
 577          */
 578         wmb();
 579         desc->hdr.state = VIO_DESC_READY;
 580
 581         err = __vdc_tx_trigger(port);
 582         if (err >= 0) {
 583                 port->req_id++;
 584                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
 585                 spin_unlock_irqrestore(&port->vio.lock, flags);
 586
 587                 wait_for_completion(&comp.com);
 588                 err = comp.err;
 589         } else {
 590                 port->vio.cmp = NULL;
 591                 spin_unlock_irqrestore(&port->vio.lock, flags);
 592         }
 593
 594         if (map_perm & LDC_MAP_W)
 595                 memcpy(buf, req_buf, len);
 596
 597         kfree(req_buf);
 598
 599         return err;
 600 }
 601
 602 static int __devinit vdc_alloc_tx_ring(struct vdc_port *port)
 603 {
 604         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 605         unsigned long len, entry_size;
 606         int ncookies;
 607         void *dring;
 608
 609         entry_size = sizeof(struct vio_disk_desc) +
 610                 (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
 611         len = (VDC_TX_RING_SIZE * entry_size);
 612
 613         ncookies = VIO_MAX_RING_COOKIES;
 614         dring = ldc_alloc_exp_dring(port->vio.lp, len,
 615                                     dr->cookies, &ncookies,
 616                                     (LDC_MAP_SHADOW |
 617                                      LDC_MAP_DIRECT |
 618                                      LDC_MAP_RW));
 619         if (IS_ERR(dring))
 620                 return PTR_ERR(dring);
 621
 622         dr->base = dring;
 623         dr->entry_size = entry_size;
 624         dr->num_entries = VDC_TX_RING_SIZE;
 625         dr->prod = dr->cons = 0;
 626         dr->pending = VDC_TX_RING_SIZE;
 627         dr->ncookies = ncookies;
 628
 629         return 0;
 630 }
 631
 632 static void vdc_free_tx_ring(struct vdc_port *port)
 633 {
 634         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 635
 636         if (dr->base) {
 637                 ldc_free_exp_dring(port->vio.lp, dr->base,
 638                                    (dr->entry_size * dr->num_entries),
 639                                    dr->cookies, dr->ncookies);
 640                 dr->base = NULL;
 641                 dr->entry_size = 0;
 642                 dr->num_entries = 0;
 643                 dr->pending = 0;
 644                 dr->ncookies = 0;
 645         }
 646 }
 647
 648 static int probe_disk(struct vdc_port *port)
 649 {
 650         struct vio_completion comp;
 651         struct request_queue *q;
 652         struct gendisk *g;
 653         int err;
 654
 655         init_completion(&comp.com);
 656         comp.err = 0;
 657         comp.waiting_for = WAITING_FOR_LINK_UP;
 658         port->vio.cmp = &comp;
 659
 660         vio_port_up(&port->vio);
 661
 662         wait_for_completion(&comp.com);
 663         if (comp.err)
 664                 return comp.err;
 665
 666         err = generic_request(port, VD_OP_GET_VTOC,
 667                               &port->label, sizeof(port->label));
 668         if (err < 0) {
 669                 printk(KERN_ERR PFX "VD_OP_GET_VTOC returns error %d\n", err);
 670                 return err;
 671         }
 672
 673         err = generic_request(port, VD_OP_GET_DISKGEOM,
 674                               &port->geom, sizeof(port->geom));
 675         if (err < 0) {
 676                 printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
 677                        "error %d\n", err);
 678                 return err;
 679         }
 680
 681         port->vdisk_size = ((u64)port->geom.num_cyl *
 682                             (u64)port->geom.num_hd *
 683                             (u64)port->geom.num_sec);
 684
 685         q = blk_init_queue(do_vdc_request, &port->vio.lock);
 686         if (!q) {
 687                 printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
 688                        port->vio.name);
 689                 return -ENOMEM;
 690         }
 691         g = alloc_disk(1 << PARTITION_SHIFT);
 692         if (!g) {
 693                 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
 694                        port->vio.name);
 695                 blk_cleanup_queue(q);
 696                 return -ENOMEM;
 697         }
 698
 699         port->disk = g;
 700
 701         blk_queue_max_hw_segments(q, port->ring_cookies);
 702         blk_queue_max_phys_segments(q, port->ring_cookies);
 703         blk_queue_max_sectors(q, port->max_xfer_size);
 704         g->major = vdc_major;
 705         g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
 706         strcpy(g->disk_name, port->disk_name);
 707
 708         g->fops = &vdc_fops;
 709         g->queue = q;
 710         g->private_data = port;
 711         g->driverfs_dev = &port->vio.vdev->dev;
 712
 713         set_capacity(g, port->vdisk_size);
 714
 715         printk(KERN_INFO PFX "%s: %u sectors (%u MB)\n",
 716                g->disk_name,
 717                port->vdisk_size, (port->vdisk_size >> (20 - 9)));
 718
 719         add_disk(g);
 720
 721         return 0;
 722 }
 723
 724 static struct ldc_channel_config vdc_ldc_cfg = {
 725         .event          = vdc_event,
 726         .mtu            = 64,
 727         .mode           = LDC_MODE_UNRELIABLE,
 728 };
 729
 730 static struct vio_driver_ops vdc_vio_ops = {
 731         .send_attr              = vdc_send_attr,
 732         .handle_attr            = vdc_handle_attr,
 733         .handshake_complete     = vdc_handshake_complete,
 734 };
 735
 736 static void print_version(void)
 737 {
 738         static int version_printed;
 739
 740         if (version_printed++ == 0)
 741                 printk(KERN_INFO "%s", version);
 742 }
 743
 744 static int __devinit vdc_port_probe(struct vio_dev *vdev,
 745                                     const struct vio_device_id *id)
 746 {
 747         struct mdesc_handle *hp;
 748         struct vdc_port *port;
 749         int err;
 750
 751         print_version();
 752
 753         hp = mdesc_grab();
 754
 755         err = -ENODEV;
 756         if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
 757                 printk(KERN_ERR PFX "Port id [%lu] too large.\n",
 758                        vdev->dev_no);
 759                 goto err_out_release_mdesc;
 760         }
 761
 762         port = kzalloc(sizeof(*port), GFP_KERNEL);
 763         err = -ENOMEM;
 764         if (!port) {
 765                 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
 766                 goto err_out_release_mdesc;
 767         }
 768
 769         if (vdev->dev_no >= 26)
 770                 snprintf(port->disk_name, sizeof(port->disk_name),
 771                          VDCBLK_NAME "%c%c",
 772                          'a' + ((int)vdev->dev_no / 26) - 1,
 773                          'a' + ((int)vdev->dev_no % 26));
 774         else
 775                 snprintf(port->disk_name, sizeof(port->disk_name),
 776                          VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
 777
 778         err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
 779                               vdc_versions, ARRAY_SIZE(vdc_versions),
 780                               &vdc_vio_ops, port->disk_name);
 781         if (err)
 782                 goto err_out_free_port;
 783
 784         port->vdisk_block_size = 512;
 785         port->max_xfer_size = ((128 * 1024) / port->vdisk_block_size);
 786         port->ring_cookies = ((port->max_xfer_size *
 787                                port->vdisk_block_size) / PAGE_SIZE) + 2;
 788
 789         err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
 790         if (err)
 791                 goto err_out_free_port;
 792
 793         err = vdc_alloc_tx_ring(port);
 794         if (err)
 795                 goto err_out_free_ldc;
 796
 797         err = probe_disk(port);
 798         if (err)
 799                 goto err_out_free_tx_ring;
 800
 801         dev_set_drvdata(&vdev->dev, port);
 802
 803         mdesc_release(hp);
 804
 805         return 0;
 806
 807 err_out_free_tx_ring:
 808         vdc_free_tx_ring(port);
 809
 810 err_out_free_ldc:
 811         vio_ldc_free(&port->vio);
 812
 813 err_out_free_port:
 814         kfree(port);
 815
 816 err_out_release_mdesc:
 817         mdesc_release(hp);
 818         return err;
 819 }
 820
 821 static int vdc_port_remove(struct vio_dev *vdev)
 822 {
 823         struct vdc_port *port = dev_get_drvdata(&vdev->dev);
 824
 825         if (port) {
 826                 del_timer_sync(&port->vio.timer);
 827
 828                 vdc_free_tx_ring(port);
 829                 vio_ldc_free(&port->vio);
 830
 831                 dev_set_drvdata(&vdev->dev, NULL);
 832
 833                 kfree(port);
 834         }
 835         return 0;
 836 }
 837
 838 static struct vio_device_id vdc_port_match[] = {
 839         {
 840                 .type = "vdc-port",
 841         },
 842         {},
 843 };
 844 MODULE_DEVICE_TABLE(vio, vdc_port_match);
 845
 846 static struct vio_driver vdc_port_driver = {
 847         .id_table       = vdc_port_match,
 848         .probe          = vdc_port_probe,
 849         .remove         = vdc_port_remove,
 850         .driver         = {
 851                 .name   = "vdc_port",
 852                 .owner  = THIS_MODULE,
 853         }
 854 };
 855
 856 static int __init vdc_init(void)
 857 {
 858         int err;
 859
 860         err = register_blkdev(0, VDCBLK_NAME);
 861         if (err < 0)
 862                 goto out_err;
 863
 864         vdc_major = err;
 865
 866         err = vio_register_driver(&vdc_port_driver);
 867         if (err)
 868                 goto out_unregister_blkdev;
 869
 870         return 0;
 871
 872 out_unregister_blkdev:
 873         unregister_blkdev(vdc_major, VDCBLK_NAME);
 874         vdc_major = 0;
 875
 876 out_err:
 877         return err;
 878 }
 879
 880 static void __exit vdc_exit(void)
 881 {
 882         vio_unregister_driver(&vdc_port_driver);
 883         unregister_blkdev(vdc_major, VDCBLK_NAME);
 884 }
 885
 886 module_init(vdc_init);
 887 module_exit(vdc_exit);