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 #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 uptodate, int num_sectors)
 216 {
 217         if (end_that_request_first(req, uptodate, num_sectors))
 218                 return;
 219         add_disk_randomness(req->rq_disk);
 220         end_that_request_last(req, uptodate);
 221 }
 222
 223 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
 224                         unsigned int index)
 225 {
 226         struct vio_disk_desc *desc = vio_dring_entry(dr, index);
 227         struct vdc_req_entry *rqe = &port->rq_arr[index];
 228         struct request *req;
 229
 230         if (unlikely(desc->hdr.state != VIO_DESC_DONE))
 231                 return;
 232
 233         ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
 234         desc->hdr.state = VIO_DESC_FREE;
 235         dr->cons = (index + 1) & (VDC_TX_RING_SIZE - 1);
 236
 237         req = rqe->req;
 238         if (req == NULL) {
 239                 vdc_end_special(port, desc);
 240                 return;
 241         }
 242
 243         rqe->req = NULL;
 244
 245         vdc_end_request(req, !desc->status, desc->size >> 9);
 246
 247         if (blk_queue_stopped(port->disk->queue))
 248                 blk_start_queue(port->disk->queue);
 249 }
 250
 251 static int vdc_ack(struct vdc_port *port, void *msgbuf)
 252 {
 253         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 254         struct vio_dring_data *pkt = msgbuf;
 255
 256         if (unlikely(pkt->dring_ident != dr->ident ||
 257                      pkt->start_idx != pkt->end_idx ||
 258                      pkt->start_idx >= VDC_TX_RING_SIZE))
 259                 return 0;
 260
 261         vdc_end_one(port, dr, pkt->start_idx);
 262
 263         return 0;
 264 }
 265
 266 static int vdc_nack(struct vdc_port *port, void *msgbuf)
 267 {
 268         /* XXX Implement me XXX */
 269         return 0;
 270 }
 271
 272 static void vdc_event(void *arg, int event)
 273 {
 274         struct vdc_port *port = arg;
 275         struct vio_driver_state *vio = &port->vio;
 276         unsigned long flags;
 277         int err;
 278
 279         spin_lock_irqsave(&vio->lock, flags);
 280
 281         if (unlikely(event == LDC_EVENT_RESET ||
 282                      event == LDC_EVENT_UP)) {
 283                 vio_link_state_change(vio, event);
 284                 spin_unlock_irqrestore(&vio->lock, flags);
 285                 return;
 286         }
 287
 288         if (unlikely(event != LDC_EVENT_DATA_READY)) {
 289                 printk(KERN_WARNING PFX "Unexpected LDC event %d\n", event);
 290                 spin_unlock_irqrestore(&vio->lock, flags);
 291                 return;
 292         }
 293
 294         err = 0;
 295         while (1) {
 296                 union {
 297                         struct vio_msg_tag tag;
 298                         u64 raw[8];
 299                 } msgbuf;
 300
 301                 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
 302                 if (unlikely(err < 0)) {
 303                         if (err == -ECONNRESET)
 304                                 vio_conn_reset(vio);
 305                         break;
 306                 }
 307                 if (err == 0)
 308                         break;
 309                 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
 310                        msgbuf.tag.type,
 311                        msgbuf.tag.stype,
 312                        msgbuf.tag.stype_env,
 313                        msgbuf.tag.sid);
 314                 err = vio_validate_sid(vio, &msgbuf.tag);
 315                 if (err < 0)
 316                         break;
 317
 318                 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
 319                         if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
 320                                 err = vdc_ack(port, &msgbuf);
 321                         else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
 322                                 err = vdc_nack(port, &msgbuf);
 323                         else
 324                                 err = vdc_handle_unknown(port, &msgbuf);
 325                 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
 326                         err = vio_control_pkt_engine(vio, &msgbuf);
 327                 } else {
 328                         err = vdc_handle_unknown(port, &msgbuf);
 329                 }
 330                 if (err < 0)
 331                         break;
 332         }
 333         if (err < 0)
 334                 vdc_finish(&port->vio, err, WAITING_FOR_ANY);
 335         spin_unlock_irqrestore(&vio->lock, flags);
 336 }
 337
 338 static int __vdc_tx_trigger(struct vdc_port *port)
 339 {
 340         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 341         struct vio_dring_data hdr = {
 342                 .tag = {
 343                         .type           = VIO_TYPE_DATA,
 344                         .stype          = VIO_SUBTYPE_INFO,
 345                         .stype_env      = VIO_DRING_DATA,
 346                         .sid            = vio_send_sid(&port->vio),
 347                 },
 348                 .dring_ident            = dr->ident,
 349                 .start_idx              = dr->prod,
 350                 .end_idx                = dr->prod,
 351         };
 352         int err, delay;
 353
 354         hdr.seq = dr->snd_nxt;
 355         delay = 1;
 356         do {
 357                 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
 358                 if (err > 0) {
 359                         dr->snd_nxt++;
 360                         break;
 361                 }
 362                 udelay(delay);
 363                 if ((delay <<= 1) > 128)
 364                         delay = 128;
 365         } while (err == -EAGAIN);
 366
 367         return err;
 368 }
 369
 370 static int __send_request(struct request *req)
 371 {
 372         struct vdc_port *port = req->rq_disk->private_data;
 373         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 374         struct scatterlist sg[port->ring_cookies];
 375         struct vdc_req_entry *rqe;
 376         struct vio_disk_desc *desc;
 377         unsigned int map_perm;
 378         int nsg, err, i;
 379         u64 len;
 380         u8 op;
 381
 382         map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 383
 384         if (rq_data_dir(req) == READ) {
 385                 map_perm |= LDC_MAP_W;
 386                 op = VD_OP_BREAD;
 387         } else {
 388                 map_perm |= LDC_MAP_R;
 389                 op = VD_OP_BWRITE;
 390         }
 391
 392         sg_init_table(sg, port->ring_cookies);
 393         nsg = blk_rq_map_sg(req->q, req, sg);
 394
 395         len = 0;
 396         for (i = 0; i < nsg; i++)
 397                 len += sg[i].length;
 398
 399         if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
 400                 blk_stop_queue(port->disk->queue);
 401                 err = -ENOMEM;
 402                 goto out;
 403         }
 404
 405         desc = vio_dring_cur(dr);
 406
 407         err = ldc_map_sg(port->vio.lp, sg, nsg,
 408                          desc->cookies, port->ring_cookies,
 409                          map_perm);
 410         if (err < 0) {
 411                 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
 412                 return err;
 413         }
 414
 415         rqe = &port->rq_arr[dr->prod];
 416         rqe->req = req;
 417
 418         desc->hdr.ack = VIO_ACK_ENABLE;
 419         desc->req_id = port->req_id;
 420         desc->operation = op;
 421         if (port->vdisk_type == VD_DISK_TYPE_DISK) {
 422                 desc->slice = 0xff;
 423         } else {
 424                 desc->slice = 0;
 425         }
 426         desc->status = ~0;
 427         desc->offset = (req->sector << 9) / port->vdisk_block_size;
 428         desc->size = len;
 429         desc->ncookies = err;
 430
 431         /* This has to be a non-SMP write barrier because we are writing
 432          * to memory which is shared with the peer LDOM.
 433          */
 434         wmb();
 435         desc->hdr.state = VIO_DESC_READY;
 436
 437         err = __vdc_tx_trigger(port);
 438         if (err < 0) {
 439                 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
 440         } else {
 441                 port->req_id++;
 442                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
 443         }
 444 out:
 445
 446         return err;
 447 }
 448
 449 static void do_vdc_request(struct request_queue *q)
 450 {
 451         while (1) {
 452                 struct request *req = elv_next_request(q);
 453
 454                 if (!req)
 455                         break;
 456
 457                 blkdev_dequeue_request(req);
 458                 if (__send_request(req) < 0)
 459                         vdc_end_request(req, 0, req->hard_nr_sectors);
 460         }
 461 }
 462
 463 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
 464 {
 465         struct vio_dring_state *dr;
 466         struct vio_completion comp;
 467         struct vio_disk_desc *desc;
 468         unsigned int map_perm;
 469         unsigned long flags;
 470         int op_len, err;
 471         void *req_buf;
 472
 473         if (!(((u64)1 << ((u64)op - 1)) & port->operations))
 474                 return -EOPNOTSUPP;
 475
 476         switch (op) {
 477         case VD_OP_BREAD:
 478         case VD_OP_BWRITE:
 479         default:
 480                 return -EINVAL;
 481
 482         case VD_OP_FLUSH:
 483                 op_len = 0;
 484                 map_perm = 0;
 485                 break;
 486
 487         case VD_OP_GET_WCE:
 488                 op_len = sizeof(u32);
 489                 map_perm = LDC_MAP_W;
 490                 break;
 491
 492         case VD_OP_SET_WCE:
 493                 op_len = sizeof(u32);
 494                 map_perm = LDC_MAP_R;
 495                 break;
 496
 497         case VD_OP_GET_VTOC:
 498                 op_len = sizeof(struct vio_disk_vtoc);
 499                 map_perm = LDC_MAP_W;
 500                 break;
 501
 502         case VD_OP_SET_VTOC:
 503                 op_len = sizeof(struct vio_disk_vtoc);
 504                 map_perm = LDC_MAP_R;
 505                 break;
 506
 507         case VD_OP_GET_DISKGEOM:
 508                 op_len = sizeof(struct vio_disk_geom);
 509                 map_perm = LDC_MAP_W;
 510                 break;
 511
 512         case VD_OP_SET_DISKGEOM:
 513                 op_len = sizeof(struct vio_disk_geom);
 514                 map_perm = LDC_MAP_R;
 515                 break;
 516
 517         case VD_OP_SCSICMD:
 518                 op_len = 16;
 519                 map_perm = LDC_MAP_RW;
 520                 break;
 521
 522         case VD_OP_GET_DEVID:
 523                 op_len = sizeof(struct vio_disk_devid);
 524                 map_perm = LDC_MAP_W;
 525                 break;
 526
 527         case VD_OP_GET_EFI:
 528         case VD_OP_SET_EFI:
 529                 return -EOPNOTSUPP;
 530                 break;
 531         };
 532
 533         map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 534
 535         op_len = (op_len + 7) & ~7;
 536         req_buf = kzalloc(op_len, GFP_KERNEL);
 537         if (!req_buf)
 538                 return -ENOMEM;
 539
 540         if (len > op_len)
 541                 len = op_len;
 542
 543         if (map_perm & LDC_MAP_R)
 544                 memcpy(req_buf, buf, len);
 545
 546         spin_lock_irqsave(&port->vio.lock, flags);
 547
 548         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 549
 550         /* XXX If we want to use this code generically we have to
 551          * XXX handle TX ring exhaustion etc.
 552          */
 553         desc = vio_dring_cur(dr);
 554
 555         err = ldc_map_single(port->vio.lp, req_buf, op_len,
 556                              desc->cookies, port->ring_cookies,
 557                              map_perm);
 558         if (err < 0) {
 559                 spin_unlock_irqrestore(&port->vio.lock, flags);
 560                 kfree(req_buf);
 561                 return err;
 562         }
 563
 564         init_completion(&comp.com);
 565         comp.waiting_for = WAITING_FOR_GEN_CMD;
 566         port->vio.cmp = &comp;
 567
 568         desc->hdr.ack = VIO_ACK_ENABLE;
 569         desc->req_id = port->req_id;
 570         desc->operation = op;
 571         desc->slice = 0;
 572         desc->status = ~0;
 573         desc->offset = 0;
 574         desc->size = op_len;
 575         desc->ncookies = err;
 576
 577         /* This has to be a non-SMP write barrier because we are writing
 578          * to memory which is shared with the peer LDOM.
 579          */
 580         wmb();
 581         desc->hdr.state = VIO_DESC_READY;
 582
 583         err = __vdc_tx_trigger(port);
 584         if (err >= 0) {
 585                 port->req_id++;
 586                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
 587                 spin_unlock_irqrestore(&port->vio.lock, flags);
 588
 589                 wait_for_completion(&comp.com);
 590                 err = comp.err;
 591         } else {
 592                 port->vio.cmp = NULL;
 593                 spin_unlock_irqrestore(&port->vio.lock, flags);
 594         }
 595
 596         if (map_perm & LDC_MAP_W)
 597                 memcpy(buf, req_buf, len);
 598
 599         kfree(req_buf);
 600
 601         return err;
 602 }
 603
 604 static int __devinit vdc_alloc_tx_ring(struct vdc_port *port)
 605 {
 606         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 607         unsigned long len, entry_size;
 608         int ncookies;
 609         void *dring;
 610
 611         entry_size = sizeof(struct vio_disk_desc) +
 612                 (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
 613         len = (VDC_TX_RING_SIZE * entry_size);
 614
 615         ncookies = VIO_MAX_RING_COOKIES;
 616         dring = ldc_alloc_exp_dring(port->vio.lp, len,
 617                                     dr->cookies, &ncookies,
 618                                     (LDC_MAP_SHADOW |
 619                                      LDC_MAP_DIRECT |
 620                                      LDC_MAP_RW));
 621         if (IS_ERR(dring))
 622                 return PTR_ERR(dring);
 623
 624         dr->base = dring;
 625         dr->entry_size = entry_size;
 626         dr->num_entries = VDC_TX_RING_SIZE;
 627         dr->prod = dr->cons = 0;
 628         dr->pending = VDC_TX_RING_SIZE;
 629         dr->ncookies = ncookies;
 630
 631         return 0;
 632 }
 633
 634 static void vdc_free_tx_ring(struct vdc_port *port)
 635 {
 636         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 637
 638         if (dr->base) {
 639                 ldc_free_exp_dring(port->vio.lp, dr->base,
 640                                    (dr->entry_size * dr->num_entries),
 641                                    dr->cookies, dr->ncookies);
 642                 dr->base = NULL;
 643                 dr->entry_size = 0;
 644                 dr->num_entries = 0;
 645                 dr->pending = 0;
 646                 dr->ncookies = 0;
 647         }
 648 }
 649
 650 static int probe_disk(struct vdc_port *port)
 651 {
 652         struct vio_completion comp;
 653         struct request_queue *q;
 654         struct gendisk *g;
 655         int err;
 656
 657         init_completion(&comp.com);
 658         comp.err = 0;
 659         comp.waiting_for = WAITING_FOR_LINK_UP;
 660         port->vio.cmp = &comp;
 661
 662         vio_port_up(&port->vio);
 663
 664         wait_for_completion(&comp.com);
 665         if (comp.err)
 666                 return comp.err;
 667
 668         err = generic_request(port, VD_OP_GET_VTOC,
 669                               &port->label, sizeof(port->label));
 670         if (err < 0) {
 671                 printk(KERN_ERR PFX "VD_OP_GET_VTOC returns error %d\n", err);
 672                 return err;
 673         }
 674
 675         err = generic_request(port, VD_OP_GET_DISKGEOM,
 676                               &port->geom, sizeof(port->geom));
 677         if (err < 0) {
 678                 printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
 679                        "error %d\n", err);
 680                 return err;
 681         }
 682
 683         port->vdisk_size = ((u64)port->geom.num_cyl *
 684                             (u64)port->geom.num_hd *
 685                             (u64)port->geom.num_sec);
 686
 687         q = blk_init_queue(do_vdc_request, &port->vio.lock);
 688         if (!q) {
 689                 printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
 690                        port->vio.name);
 691                 return -ENOMEM;
 692         }
 693         g = alloc_disk(1 << PARTITION_SHIFT);
 694         if (!g) {
 695                 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
 696                        port->vio.name);
 697                 blk_cleanup_queue(q);
 698                 return -ENOMEM;
 699         }
 700
 701         port->disk = g;
 702
 703         blk_queue_max_hw_segments(q, port->ring_cookies);
 704         blk_queue_max_phys_segments(q, port->ring_cookies);
 705         blk_queue_max_sectors(q, port->max_xfer_size);
 706         g->major = vdc_major;
 707         g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
 708         strcpy(g->disk_name, port->disk_name);
 709
 710         g->fops = &vdc_fops;
 711         g->queue = q;
 712         g->private_data = port;
 713         g->driverfs_dev = &port->vio.vdev->dev;
 714
 715         set_capacity(g, port->vdisk_size);
 716
 717         printk(KERN_INFO PFX "%s: %u sectors (%u MB)\n",
 718                g->disk_name,
 719                port->vdisk_size, (port->vdisk_size >> (20 - 9)));
 720
 721         add_disk(g);
 722
 723         return 0;
 724 }
 725
 726 static struct ldc_channel_config vdc_ldc_cfg = {
 727         .event          = vdc_event,
 728         .mtu            = 64,
 729         .mode           = LDC_MODE_UNRELIABLE,
 730 };
 731
 732 static struct vio_driver_ops vdc_vio_ops = {
 733         .send_attr              = vdc_send_attr,
 734         .handle_attr            = vdc_handle_attr,
 735         .handshake_complete     = vdc_handshake_complete,
 736 };
 737
 738 static void print_version(void)
 739 {
 740         static int version_printed;
 741
 742         if (version_printed++ == 0)
 743                 printk(KERN_INFO "%s", version);
 744 }
 745
 746 static int __devinit vdc_port_probe(struct vio_dev *vdev,
 747                                     const struct vio_device_id *id)
 748 {
 749         struct mdesc_handle *hp;
 750         struct vdc_port *port;
 751         int err;
 752
 753         print_version();
 754
 755         hp = mdesc_grab();
 756
 757         err = -ENODEV;
 758         if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
 759                 printk(KERN_ERR PFX "Port id [%lu] too large.\n",
 760                        vdev->dev_no);
 761                 goto err_out_release_mdesc;
 762         }
 763
 764         port = kzalloc(sizeof(*port), GFP_KERNEL);
 765         err = -ENOMEM;
 766         if (!port) {
 767                 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
 768                 goto err_out_release_mdesc;
 769         }
 770
 771         if (vdev->dev_no >= 26)
 772                 snprintf(port->disk_name, sizeof(port->disk_name),
 773                          VDCBLK_NAME "%c%c",
 774                          'a' + ((int)vdev->dev_no / 26) - 1,
 775                          'a' + ((int)vdev->dev_no % 26));
 776         else
 777                 snprintf(port->disk_name, sizeof(port->disk_name),
 778                          VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
 779
 780         err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
 781                               vdc_versions, ARRAY_SIZE(vdc_versions),
 782                               &vdc_vio_ops, port->disk_name);
 783         if (err)
 784                 goto err_out_free_port;
 785
 786         port->vdisk_block_size = 512;
 787         port->max_xfer_size = ((128 * 1024) / port->vdisk_block_size);
 788         port->ring_cookies = ((port->max_xfer_size *
 789                                port->vdisk_block_size) / PAGE_SIZE) + 2;
 790
 791         err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
 792         if (err)
 793                 goto err_out_free_port;
 794
 795         err = vdc_alloc_tx_ring(port);
 796         if (err)
 797                 goto err_out_free_ldc;
 798
 799         err = probe_disk(port);
 800         if (err)
 801                 goto err_out_free_tx_ring;
 802
 803         dev_set_drvdata(&vdev->dev, port);
 804
 805         mdesc_release(hp);
 806
 807         return 0;
 808
 809 err_out_free_tx_ring:
 810         vdc_free_tx_ring(port);
 811
 812 err_out_free_ldc:
 813         vio_ldc_free(&port->vio);
 814
 815 err_out_free_port:
 816         kfree(port);
 817
 818 err_out_release_mdesc:
 819         mdesc_release(hp);
 820         return err;
 821 }
 822
 823 static int vdc_port_remove(struct vio_dev *vdev)
 824 {
 825         struct vdc_port *port = dev_get_drvdata(&vdev->dev);
 826
 827         if (port) {
 828                 del_timer_sync(&port->vio.timer);
 829
 830                 vdc_free_tx_ring(port);
 831                 vio_ldc_free(&port->vio);
 832
 833                 dev_set_drvdata(&vdev->dev, NULL);
 834
 835                 kfree(port);
 836         }
 837         return 0;
 838 }
 839
 840 static struct vio_device_id vdc_port_match[] = {
 841         {
 842                 .type = "vdc-port",
 843         },
 844         {},
 845 };
 846 MODULE_DEVICE_TABLE(vio, vdc_port_match);
 847
 848 static struct vio_driver vdc_port_driver = {
 849         .id_table       = vdc_port_match,
 850         .probe          = vdc_port_probe,
 851         .remove         = vdc_port_remove,
 852         .driver         = {
 853                 .name   = "vdc_port",
 854                 .owner  = THIS_MODULE,
 855         }
 856 };
 857
 858 static int __init vdc_init(void)
 859 {
 860         int err;
 861
 862         err = register_blkdev(0, VDCBLK_NAME);
 863         if (err < 0)
 864                 goto out_err;
 865
 866         vdc_major = err;
 867
 868         err = vio_register_driver(&vdc_port_driver);
 869         if (err)
 870                 goto out_unregister_blkdev;
 871
 872         return 0;
 873
 874 out_unregister_blkdev:
 875         unregister_blkdev(vdc_major, VDCBLK_NAME);
 876         vdc_major = 0;
 877
 878 out_err:
 879         return err;
 880 }
 881
 882 static void __exit vdc_exit(void)
 883 {
 884         vio_unregister_driver(&vdc_port_driver);
 885         unregister_blkdev(vdc_major, VDCBLK_NAME);
 886 }
 887
 888 module_init(vdc_init);
 889 module_exit(vdc_exit);