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, 2008 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 #include <linux/scatterlist.h>
  19
  20 #include <asm/vio.h>
  21 #include <asm/ldc.h>
  22
  23 #define DRV_MODULE_NAME         "sunvdc"
  24 #define PFX DRV_MODULE_NAME     ": "
  25 #define DRV_MODULE_VERSION      "1.0"
  26 #define DRV_MODULE_RELDATE      "June 25, 2007"
  27
  28 static char version[] __devinitdata =
  29         DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
  30 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
  31 MODULE_DESCRIPTION("Sun LDOM virtual disk client driver");
  32 MODULE_LICENSE("GPL");
  33 MODULE_VERSION(DRV_MODULE_VERSION);
  34
  35 #define VDC_TX_RING_SIZE        256
  36
  37 #define WAITING_FOR_LINK_UP     0x01
  38 #define WAITING_FOR_TX_SPACE    0x02
  39 #define WAITING_FOR_GEN_CMD     0x04
  40 #define WAITING_FOR_ANY         -1
  41
  42 struct vdc_req_entry {
  43         struct request          *req;
  44 };
  45
  46 struct vdc_port {
  47         struct vio_driver_state vio;
  48
  49         struct gendisk          *disk;
  50
  51         struct vdc_completion   *cmp;
  52
  53         u64                     req_id;
  54         u64                     seq;
  55         struct vdc_req_entry    rq_arr[VDC_TX_RING_SIZE];
  56
  57         unsigned long           ring_cookies;
  58
  59         u64                     max_xfer_size;
  60         u32                     vdisk_block_size;
  61
  62         /* The server fills these in for us in the disk attribute
  63          * ACK packet.
  64          */
  65         u64                     operations;
  66         u32                     vdisk_size;
  67         u8                      vdisk_type;
  68
  69         char                    disk_name[32];
  70
  71         struct vio_disk_geom    geom;
  72         struct vio_disk_vtoc    label;
  73 };
  74
  75 static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
  76 {
  77         return container_of(vio, struct vdc_port, vio);
  78 }
  79
  80 /* Ordered from largest major to lowest */
  81 static struct vio_version vdc_versions[] = {
  82         { .major = 1, .minor = 0 },
  83 };
  84
  85 #define VDCBLK_NAME     "vdisk"
  86 static int vdc_major;
  87 #define PARTITION_SHIFT 3
  88
  89 static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr)
  90 {
  91         return vio_dring_avail(dr, VDC_TX_RING_SIZE);
  92 }
  93
  94 static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo)
  95 {
  96         struct gendisk *disk = bdev->bd_disk;
  97         struct vdc_port *port = disk->private_data;
  98
  99         geo->heads = (u8) port->geom.num_hd;
 100         geo->sectors = (u8) port->geom.num_sec;
 101         geo->cylinders = port->geom.num_cyl;
 102
 103         return 0;
 104 }
 105
 106 static struct block_device_operations vdc_fops = {
 107         .owner          = THIS_MODULE,
 108         .getgeo         = vdc_getgeo,
 109 };
 110
 111 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)
 112 {
 113         if (vio->cmp &&
 114             (waiting_for == -1 ||
 115              vio->cmp->waiting_for == waiting_for)) {
 116                 vio->cmp->err = err;
 117                 complete(&vio->cmp->com);
 118                 vio->cmp = NULL;
 119         }
 120 }
 121
 122 static void vdc_handshake_complete(struct vio_driver_state *vio)
 123 {
 124         vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
 125 }
 126
 127 static int vdc_handle_unknown(struct vdc_port *port, void *arg)
 128 {
 129         struct vio_msg_tag *pkt = arg;
 130
 131         printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n",
 132                pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
 133         printk(KERN_ERR PFX "Resetting connection.\n");
 134
 135         ldc_disconnect(port->vio.lp);
 136
 137         return -ECONNRESET;
 138 }
 139
 140 static int vdc_send_attr(struct vio_driver_state *vio)
 141 {
 142         struct vdc_port *port = to_vdc_port(vio);
 143         struct vio_disk_attr_info pkt;
 144
 145         memset(&pkt, 0, sizeof(pkt));
 146
 147         pkt.tag.type = VIO_TYPE_CTRL;
 148         pkt.tag.stype = VIO_SUBTYPE_INFO;
 149         pkt.tag.stype_env = VIO_ATTR_INFO;
 150         pkt.tag.sid = vio_send_sid(vio);
 151
 152         pkt.xfer_mode = VIO_DRING_MODE;
 153         pkt.vdisk_block_size = port->vdisk_block_size;
 154         pkt.max_xfer_size = port->max_xfer_size;
 155
 156         viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%lu]\n",
 157                pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size);
 158
 159         return vio_ldc_send(&port->vio, &pkt, sizeof(pkt));
 160 }
 161
 162 static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
 163 {
 164         struct vdc_port *port = to_vdc_port(vio);
 165         struct vio_disk_attr_info *pkt = arg;
 166
 167         viodbg(HS, "GOT ATTR stype[0x%x] ops[%lx] disk_size[%lu] disk_type[%x] "
 168                "xfer_mode[0x%x] blksz[%u] max_xfer[%lu]\n",
 169                pkt->tag.stype, pkt->operations,
 170                pkt->vdisk_size, pkt->vdisk_type,
 171                pkt->xfer_mode, pkt->vdisk_block_size,
 172                pkt->max_xfer_size);
 173
 174         if (pkt->tag.stype == VIO_SUBTYPE_ACK) {
 175                 switch (pkt->vdisk_type) {
 176                 case VD_DISK_TYPE_DISK:
 177                 case VD_DISK_TYPE_SLICE:
 178                         break;
 179
 180                 default:
 181                         printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n",
 182                                vio->name, pkt->vdisk_type);
 183                         return -ECONNRESET;
 184                 }
 185
 186                 if (pkt->vdisk_block_size > port->vdisk_block_size) {
 187                         printk(KERN_ERR PFX "%s: BLOCK size increased "
 188                                "%u --> %u\n",
 189                                vio->name,
 190                                port->vdisk_block_size, pkt->vdisk_block_size);
 191                         return -ECONNRESET;
 192                 }
 193
 194                 port->operations = pkt->operations;
 195                 port->vdisk_size = pkt->vdisk_size;
 196                 port->vdisk_type = pkt->vdisk_type;
 197                 if (pkt->max_xfer_size < port->max_xfer_size)
 198                         port->max_xfer_size = pkt->max_xfer_size;
 199                 port->vdisk_block_size = pkt->vdisk_block_size;
 200                 return 0;
 201         } else {
 202                 printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name);
 203
 204                 return -ECONNRESET;
 205         }
 206 }
 207
 208 static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc)
 209 {
 210         int err = desc->status;
 211
 212         vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD);
 213 }
 214
 215 static void vdc_end_request(struct request *req, int error, int num_sectors)
 216 {
 217         __blk_end_request(req, error, num_sectors << 9);
 218 }
 219
 220 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
 221                         unsigned int index)
 222 {
 223         struct vio_disk_desc *desc = vio_dring_entry(dr, index);
 224         struct vdc_req_entry *rqe = &port->rq_arr[index];
 225         struct request *req;
 226
 227         if (unlikely(desc->hdr.state != VIO_DESC_DONE))
 228                 return;
 229
 230         ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
 231         desc->hdr.state = VIO_DESC_FREE;
 232         dr->cons = (index + 1) & (VDC_TX_RING_SIZE - 1);
 233
 234         req = rqe->req;
 235         if (req == NULL) {
 236                 vdc_end_special(port, desc);
 237                 return;
 238         }
 239
 240         rqe->req = NULL;
 241
 242         vdc_end_request(req, (desc->status ? -EIO : 0), desc->size >> 9);
 243
 244         if (blk_queue_stopped(port->disk->queue))
 245                 blk_start_queue(port->disk->queue);
 246 }
 247
 248 static int vdc_ack(struct vdc_port *port, void *msgbuf)
 249 {
 250         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 251         struct vio_dring_data *pkt = msgbuf;
 252
 253         if (unlikely(pkt->dring_ident != dr->ident ||
 254                      pkt->start_idx != pkt->end_idx ||
 255                      pkt->start_idx >= VDC_TX_RING_SIZE))
 256                 return 0;
 257
 258         vdc_end_one(port, dr, pkt->start_idx);
 259
 260         return 0;
 261 }
 262
 263 static int vdc_nack(struct vdc_port *port, void *msgbuf)
 264 {
 265         /* XXX Implement me XXX */
 266         return 0;
 267 }
 268
 269 static void vdc_event(void *arg, int event)
 270 {
 271         struct vdc_port *port = arg;
 272         struct vio_driver_state *vio = &port->vio;
 273         unsigned long flags;
 274         int err;
 275
 276         spin_lock_irqsave(&vio->lock, flags);
 277
 278         if (unlikely(event == LDC_EVENT_RESET ||
 279                      event == LDC_EVENT_UP)) {
 280                 vio_link_state_change(vio, event);
 281                 spin_unlock_irqrestore(&vio->lock, flags);
 282                 return;
 283         }
 284
 285         if (unlikely(event != LDC_EVENT_DATA_READY)) {
 286                 printk(KERN_WARNING PFX "Unexpected LDC event %d\n", event);
 287                 spin_unlock_irqrestore(&vio->lock, flags);
 288                 return;
 289         }
 290
 291         err = 0;
 292         while (1) {
 293                 union {
 294                         struct vio_msg_tag tag;
 295                         u64 raw[8];
 296                 } msgbuf;
 297
 298                 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
 299                 if (unlikely(err < 0)) {
 300                         if (err == -ECONNRESET)
 301                                 vio_conn_reset(vio);
 302                         break;
 303                 }
 304                 if (err == 0)
 305                         break;
 306                 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
 307                        msgbuf.tag.type,
 308                        msgbuf.tag.stype,
 309                        msgbuf.tag.stype_env,
 310                        msgbuf.tag.sid);
 311                 err = vio_validate_sid(vio, &msgbuf.tag);
 312                 if (err < 0)
 313                         break;
 314
 315                 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
 316                         if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
 317                                 err = vdc_ack(port, &msgbuf);
 318                         else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
 319                                 err = vdc_nack(port, &msgbuf);
 320                         else
 321                                 err = vdc_handle_unknown(port, &msgbuf);
 322                 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
 323                         err = vio_control_pkt_engine(vio, &msgbuf);
 324                 } else {
 325                         err = vdc_handle_unknown(port, &msgbuf);
 326                 }
 327                 if (err < 0)
 328                         break;
 329         }
 330         if (err < 0)
 331                 vdc_finish(&port->vio, err, WAITING_FOR_ANY);
 332         spin_unlock_irqrestore(&vio->lock, flags);
 333 }
 334
 335 static int __vdc_tx_trigger(struct vdc_port *port)
 336 {
 337         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 338         struct vio_dring_data hdr = {
 339                 .tag = {
 340                         .type           = VIO_TYPE_DATA,
 341                         .stype          = VIO_SUBTYPE_INFO,
 342                         .stype_env      = VIO_DRING_DATA,
 343                         .sid            = vio_send_sid(&port->vio),
 344                 },
 345                 .dring_ident            = dr->ident,
 346                 .start_idx              = dr->prod,
 347                 .end_idx                = dr->prod,
 348         };
 349         int err, delay;
 350
 351         hdr.seq = dr->snd_nxt;
 352         delay = 1;
 353         do {
 354                 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
 355                 if (err > 0) {
 356                         dr->snd_nxt++;
 357                         break;
 358                 }
 359                 udelay(delay);
 360                 if ((delay <<= 1) > 128)
 361                         delay = 128;
 362         } while (err == -EAGAIN);
 363
 364         return err;
 365 }
 366
 367 static int __send_request(struct request *req)
 368 {
 369         struct vdc_port *port = req->rq_disk->private_data;
 370         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 371         struct scatterlist sg[port->ring_cookies];
 372         struct vdc_req_entry *rqe;
 373         struct vio_disk_desc *desc;
 374         unsigned int map_perm;
 375         int nsg, err, i;
 376         u64 len;
 377         u8 op;
 378
 379         map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 380
 381         if (rq_data_dir(req) == READ) {
 382                 map_perm |= LDC_MAP_W;
 383                 op = VD_OP_BREAD;
 384         } else {
 385                 map_perm |= LDC_MAP_R;
 386                 op = VD_OP_BWRITE;
 387         }
 388
 389         sg_init_table(sg, port->ring_cookies);
 390         nsg = blk_rq_map_sg(req->q, req, sg);
 391
 392         len = 0;
 393         for (i = 0; i < nsg; i++)
 394                 len += sg[i].length;
 395
 396         if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
 397                 blk_stop_queue(port->disk->queue);
 398                 err = -ENOMEM;
 399                 goto out;
 400         }
 401
 402         desc = vio_dring_cur(dr);
 403
 404         err = ldc_map_sg(port->vio.lp, sg, nsg,
 405                          desc->cookies, port->ring_cookies,
 406                          map_perm);
 407         if (err < 0) {
 408                 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
 409                 return err;
 410         }
 411
 412         rqe = &port->rq_arr[dr->prod];
 413         rqe->req = req;
 414
 415         desc->hdr.ack = VIO_ACK_ENABLE;
 416         desc->req_id = port->req_id;
 417         desc->operation = op;
 418         if (port->vdisk_type == VD_DISK_TYPE_DISK) {
 419                 desc->slice = 0xff;
 420         } else {
 421                 desc->slice = 0;
 422         }
 423         desc->status = ~0;
 424         desc->offset = (req->sector << 9) / port->vdisk_block_size;
 425         desc->size = len;
 426         desc->ncookies = err;
 427
 428         /* This has to be a non-SMP write barrier because we are writing
 429          * to memory which is shared with the peer LDOM.
 430          */
 431         wmb();
 432         desc->hdr.state = VIO_DESC_READY;
 433
 434         err = __vdc_tx_trigger(port);
 435         if (err < 0) {
 436                 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
 437         } else {
 438                 port->req_id++;
 439                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
 440         }
 441 out:
 442
 443         return err;
 444 }
 445
 446 static void do_vdc_request(struct request_queue *q)
 447 {
 448         while (1) {
 449                 struct request *req = elv_next_request(q);
 450
 451                 if (!req)
 452                         break;
 453
 454                 blkdev_dequeue_request(req);
 455                 if (__send_request(req) < 0)
 456                         vdc_end_request(req, -EIO, req->hard_nr_sectors);
 457         }
 458 }
 459
 460 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
 461 {
 462         struct vio_dring_state *dr;
 463         struct vio_completion comp;
 464         struct vio_disk_desc *desc;
 465         unsigned int map_perm;
 466         unsigned long flags;
 467         int op_len, err;
 468         void *req_buf;
 469
 470         if (!(((u64)1 << ((u64)op - 1)) & port->operations))
 471                 return -EOPNOTSUPP;
 472
 473         switch (op) {
 474         case VD_OP_BREAD:
 475         case VD_OP_BWRITE:
 476         default:
 477                 return -EINVAL;
 478
 479         case VD_OP_FLUSH:
 480                 op_len = 0;
 481                 map_perm = 0;
 482                 break;
 483
 484         case VD_OP_GET_WCE:
 485                 op_len = sizeof(u32);
 486                 map_perm = LDC_MAP_W;
 487                 break;
 488
 489         case VD_OP_SET_WCE:
 490                 op_len = sizeof(u32);
 491                 map_perm = LDC_MAP_R;
 492                 break;
 493
 494         case VD_OP_GET_VTOC:
 495                 op_len = sizeof(struct vio_disk_vtoc);
 496                 map_perm = LDC_MAP_W;
 497                 break;
 498
 499         case VD_OP_SET_VTOC:
 500                 op_len = sizeof(struct vio_disk_vtoc);
 501                 map_perm = LDC_MAP_R;
 502                 break;
 503
 504         case VD_OP_GET_DISKGEOM:
 505                 op_len = sizeof(struct vio_disk_geom);
 506                 map_perm = LDC_MAP_W;
 507                 break;
 508
 509         case VD_OP_SET_DISKGEOM:
 510                 op_len = sizeof(struct vio_disk_geom);
 511                 map_perm = LDC_MAP_R;
 512                 break;
 513
 514         case VD_OP_SCSICMD:
 515                 op_len = 16;
 516                 map_perm = LDC_MAP_RW;
 517                 break;
 518
 519         case VD_OP_GET_DEVID:
 520                 op_len = sizeof(struct vio_disk_devid);
 521                 map_perm = LDC_MAP_W;
 522                 break;
 523
 524         case VD_OP_GET_EFI:
 525         case VD_OP_SET_EFI:
 526                 return -EOPNOTSUPP;
 527                 break;
 528         };
 529
 530         map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 531
 532         op_len = (op_len + 7) & ~7;
 533         req_buf = kzalloc(op_len, GFP_KERNEL);
 534         if (!req_buf)
 535                 return -ENOMEM;
 536
 537         if (len > op_len)
 538                 len = op_len;
 539
 540         if (map_perm & LDC_MAP_R)
 541                 memcpy(req_buf, buf, len);
 542
 543         spin_lock_irqsave(&port->vio.lock, flags);
 544
 545         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 546
 547         /* XXX If we want to use this code generically we have to
 548          * XXX handle TX ring exhaustion etc.
 549          */
 550         desc = vio_dring_cur(dr);
 551
 552         err = ldc_map_single(port->vio.lp, req_buf, op_len,
 553                              desc->cookies, port->ring_cookies,
 554                              map_perm);
 555         if (err < 0) {
 556                 spin_unlock_irqrestore(&port->vio.lock, flags);
 557                 kfree(req_buf);
 558                 return err;
 559         }
 560
 561         init_completion(&comp.com);
 562         comp.waiting_for = WAITING_FOR_GEN_CMD;
 563         port->vio.cmp = &comp;
 564
 565         desc->hdr.ack = VIO_ACK_ENABLE;
 566         desc->req_id = port->req_id;
 567         desc->operation = op;
 568         desc->slice = 0;
 569         desc->status = ~0;
 570         desc->offset = 0;
 571         desc->size = op_len;
 572         desc->ncookies = err;
 573
 574         /* This has to be a non-SMP write barrier because we are writing
 575          * to memory which is shared with the peer LDOM.
 576          */
 577         wmb();
 578         desc->hdr.state = VIO_DESC_READY;
 579
 580         err = __vdc_tx_trigger(port);
 581         if (err >= 0) {
 582                 port->req_id++;
 583                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
 584                 spin_unlock_irqrestore(&port->vio.lock, flags);
 585
 586                 wait_for_completion(&comp.com);
 587                 err = comp.err;
 588         } else {
 589                 port->vio.cmp = NULL;
 590                 spin_unlock_irqrestore(&port->vio.lock, flags);
 591         }
 592
 593         if (map_perm & LDC_MAP_W)
 594                 memcpy(buf, req_buf, len);
 595
 596         kfree(req_buf);
 597
 598         return err;
 599 }
 600
 601 static int __devinit vdc_alloc_tx_ring(struct vdc_port *port)
 602 {
 603         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 604         unsigned long len, entry_size;
 605         int ncookies;
 606         void *dring;
 607
 608         entry_size = sizeof(struct vio_disk_desc) +
 609                 (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
 610         len = (VDC_TX_RING_SIZE * entry_size);
 611
 612         ncookies = VIO_MAX_RING_COOKIES;
 613         dring = ldc_alloc_exp_dring(port->vio.lp, len,
 614                                     dr->cookies, &ncookies,
 615                                     (LDC_MAP_SHADOW |
 616                                      LDC_MAP_DIRECT |
 617                                      LDC_MAP_RW));
 618         if (IS_ERR(dring))
 619                 return PTR_ERR(dring);
 620
 621         dr->base = dring;
 622         dr->entry_size = entry_size;
 623         dr->num_entries = VDC_TX_RING_SIZE;
 624         dr->prod = dr->cons = 0;
 625         dr->pending = VDC_TX_RING_SIZE;
 626         dr->ncookies = ncookies;
 627
 628         return 0;
 629 }
 630
 631 static void vdc_free_tx_ring(struct vdc_port *port)
 632 {
 633         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 634
 635         if (dr->base) {
 636                 ldc_free_exp_dring(port->vio.lp, dr->base,
 637                                    (dr->entry_size * dr->num_entries),
 638                                    dr->cookies, dr->ncookies);
 639                 dr->base = NULL;
 640                 dr->entry_size = 0;
 641                 dr->num_entries = 0;
 642                 dr->pending = 0;
 643                 dr->ncookies = 0;
 644         }
 645 }
 646
 647 static int probe_disk(struct vdc_port *port)
 648 {
 649         struct vio_completion comp;
 650         struct request_queue *q;
 651         struct gendisk *g;
 652         int err;
 653
 654         init_completion(&comp.com);
 655         comp.err = 0;
 656         comp.waiting_for = WAITING_FOR_LINK_UP;
 657         port->vio.cmp = &comp;
 658
 659         vio_port_up(&port->vio);
 660
 661         wait_for_completion(&comp.com);
 662         if (comp.err)
 663                 return comp.err;
 664
 665         err = generic_request(port, VD_OP_GET_VTOC,
 666                               &port->label, sizeof(port->label));
 667         if (err < 0) {
 668                 printk(KERN_ERR PFX "VD_OP_GET_VTOC returns error %d\n", err);
 669                 return err;
 670         }
 671
 672         err = generic_request(port, VD_OP_GET_DISKGEOM,
 673                               &port->geom, sizeof(port->geom));
 674         if (err < 0) {
 675                 printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
 676                        "error %d\n", err);
 677                 return err;
 678         }
 679
 680         port->vdisk_size = ((u64)port->geom.num_cyl *
 681                             (u64)port->geom.num_hd *
 682                             (u64)port->geom.num_sec);
 683
 684         q = blk_init_queue(do_vdc_request, &port->vio.lock);
 685         if (!q) {
 686                 printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
 687                        port->vio.name);
 688                 return -ENOMEM;
 689         }
 690         g = alloc_disk(1 << PARTITION_SHIFT);
 691         if (!g) {
 692                 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
 693                        port->vio.name);
 694                 blk_cleanup_queue(q);
 695                 return -ENOMEM;
 696         }
 697
 698         port->disk = g;
 699
 700         blk_queue_max_hw_segments(q, port->ring_cookies);
 701         blk_queue_max_phys_segments(q, port->ring_cookies);
 702         blk_queue_max_sectors(q, port->max_xfer_size);
 703         g->major = vdc_major;
 704         g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
 705         strcpy(g->disk_name, port->disk_name);
 706
 707         g->fops = &vdc_fops;
 708         g->queue = q;
 709         g->private_data = port;
 710         g->driverfs_dev = &port->vio.vdev->dev;
 711
 712         set_capacity(g, port->vdisk_size);
 713
 714         printk(KERN_INFO PFX "%s: %u sectors (%u MB)\n",
 715                g->disk_name,
 716                port->vdisk_size, (port->vdisk_size >> (20 - 9)));
 717
 718         add_disk(g);
 719
 720         return 0;
 721 }
 722
 723 static struct ldc_channel_config vdc_ldc_cfg = {
 724         .event          = vdc_event,
 725         .mtu            = 64,
 726         .mode           = LDC_MODE_UNRELIABLE,
 727 };
 728
 729 static struct vio_driver_ops vdc_vio_ops = {
 730         .send_attr              = vdc_send_attr,
 731         .handle_attr            = vdc_handle_attr,
 732         .handshake_complete     = vdc_handshake_complete,
 733 };
 734
 735 static void __devinit print_version(void)
 736 {
 737         static int version_printed;
 738
 739         if (version_printed++ == 0)
 740                 printk(KERN_INFO "%s", version);
 741 }
 742
 743 static int __devinit vdc_port_probe(struct vio_dev *vdev,
 744                                     const struct vio_device_id *id)
 745 {
 746         struct mdesc_handle *hp;
 747         struct vdc_port *port;
 748         int err;
 749
 750         print_version();
 751
 752         hp = mdesc_grab();
 753
 754         err = -ENODEV;
 755         if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
 756                 printk(KERN_ERR PFX "Port id [%lu] too large.\n",
 757                        vdev->dev_no);
 758                 goto err_out_release_mdesc;
 759         }
 760
 761         port = kzalloc(sizeof(*port), GFP_KERNEL);
 762         err = -ENOMEM;
 763         if (!port) {
 764                 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
 765                 goto err_out_release_mdesc;
 766         }
 767
 768         if (vdev->dev_no >= 26)
 769                 snprintf(port->disk_name, sizeof(port->disk_name),
 770                          VDCBLK_NAME "%c%c",
 771                          'a' + ((int)vdev->dev_no / 26) - 1,
 772                          'a' + ((int)vdev->dev_no % 26));
 773         else
 774                 snprintf(port->disk_name, sizeof(port->disk_name),
 775                          VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
 776
 777         err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
 778                               vdc_versions, ARRAY_SIZE(vdc_versions),
 779                               &vdc_vio_ops, port->disk_name);
 780         if (err)
 781                 goto err_out_free_port;
 782
 783         port->vdisk_block_size = 512;
 784         port->max_xfer_size = ((128 * 1024) / port->vdisk_block_size);
 785         port->ring_cookies = ((port->max_xfer_size *
 786                                port->vdisk_block_size) / PAGE_SIZE) + 2;
 787
 788         err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
 789         if (err)
 790                 goto err_out_free_port;
 791
 792         err = vdc_alloc_tx_ring(port);
 793         if (err)
 794                 goto err_out_free_ldc;
 795
 796         err = probe_disk(port);
 797         if (err)
 798                 goto err_out_free_tx_ring;
 799
 800         dev_set_drvdata(&vdev->dev, port);
 801
 802         mdesc_release(hp);
 803
 804         return 0;
 805
 806 err_out_free_tx_ring:
 807         vdc_free_tx_ring(port);
 808
 809 err_out_free_ldc:
 810         vio_ldc_free(&port->vio);
 811
 812 err_out_free_port:
 813         kfree(port);
 814
 815 err_out_release_mdesc:
 816         mdesc_release(hp);
 817         return err;
 818 }
 819
 820 static int vdc_port_remove(struct vio_dev *vdev)
 821 {
 822         struct vdc_port *port = dev_get_drvdata(&vdev->dev);
 823
 824         if (port) {
 825                 del_timer_sync(&port->vio.timer);
 826
 827                 vdc_free_tx_ring(port);
 828                 vio_ldc_free(&port->vio);
 829
 830                 dev_set_drvdata(&vdev->dev, NULL);
 831
 832                 kfree(port);
 833         }
 834         return 0;
 835 }
 836
 837 static const struct vio_device_id vdc_port_match[] = {
 838         {
 839                 .type = "vdc-port",
 840         },
 841         {},
 842 };
 843 MODULE_DEVICE_TABLE(vio, vdc_port_match);
 844
 845 static struct vio_driver vdc_port_driver = {
 846         .id_table       = vdc_port_match,
 847         .probe          = vdc_port_probe,
 848         .remove         = vdc_port_remove,
 849         .driver         = {
 850                 .name   = "vdc_port",
 851                 .owner  = THIS_MODULE,
 852         }
 853 };
 854
 855 static int __init vdc_init(void)
 856 {
 857         int err;
 858
 859         err = register_blkdev(0, VDCBLK_NAME);
 860         if (err < 0)
 861                 goto out_err;
 862
 863         vdc_major = err;
 864
 865         err = vio_register_driver(&vdc_port_driver);
 866         if (err)
 867                 goto out_unregister_blkdev;
 868
 869         return 0;
 870
 871 out_unregister_blkdev:
 872         unregister_blkdev(vdc_major, VDCBLK_NAME);
 873         vdc_major = 0;
 874
 875 out_err:
 876         return err;
 877 }
 878
 879 static void __exit vdc_exit(void)
 880 {
 881         vio_unregister_driver(&vdc_port_driver);
 882         unregister_blkdev(vdc_major, VDCBLK_NAME);
 883 }
 884
 885 module_init(vdc_init);
 886 module_exit(vdc_exit);