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