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/cdrom.h>
  13 #include <linux/slab.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/completion.h>
  16 #include <linux/delay.h>
  17 #include <linux/init.h>
  18 #include <linux/list.h>
  19 #include <linux/scatterlist.h>
  20
  21 #include <asm/vio.h>
  22 #include <asm/ldc.h>
  23
  24 #define DRV_MODULE_NAME         "sunvdc"
  25 #define PFX DRV_MODULE_NAME     ": "
  26 #define DRV_MODULE_VERSION      "1.1"
  27 #define DRV_MODULE_RELDATE      "February 13, 2013"
  28
  29 static char version[] =
  30         DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
  31 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
  32 MODULE_DESCRIPTION("Sun LDOM virtual disk client driver");
  33 MODULE_LICENSE("GPL");
  34 MODULE_VERSION(DRV_MODULE_VERSION);
  35
  36 #define VDC_TX_RING_SIZE        256
  37
  38 #define WAITING_FOR_LINK_UP     0x01
  39 #define WAITING_FOR_TX_SPACE    0x02
  40 #define WAITING_FOR_GEN_CMD     0x04
  41 #define WAITING_FOR_ANY         -1
  42
  43 struct vdc_req_entry {
  44         struct request          *req;
  45 };
  46
  47 struct vdc_port {
  48         struct vio_driver_state vio;
  49
  50         struct gendisk          *disk;
  51
  52         struct vdc_completion   *cmp;
  53
  54         u64                     req_id;
  55         u64                     seq;
  56         struct vdc_req_entry    rq_arr[VDC_TX_RING_SIZE];
  57
  58         unsigned long           ring_cookies;
  59
  60         u64                     max_xfer_size;
  61         u32                     vdisk_block_size;
  62
  63         /* The server fills these in for us in the disk attribute
  64          * ACK packet.
  65          */
  66         u64                     operations;
  67         u32                     vdisk_size;
  68         u8                      vdisk_type;
  69         u8                      vdisk_mtype;
  70
  71         char                    disk_name[32];
  72
  73         struct vio_disk_geom    geom;
  74         struct vio_disk_vtoc    label;
  75 };
  76
  77 static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
  78 {
  79         return container_of(vio, struct vdc_port, vio);
  80 }
  81
  82 /* Ordered from largest major to lowest */
  83 static struct vio_version vdc_versions[] = {
  84         { .major = 1, .minor = 1 },
  85         { .major = 1, .minor = 0 },
  86 };
  87
  88 static inline int vdc_version_supported(struct vdc_port *port,
  89                                         u16 major, u16 minor)
  90 {
  91         return port->vio.ver.major == major && port->vio.ver.minor >= minor;
  92 }
  93
  94 #define VDCBLK_NAME     "vdisk"
  95 static int vdc_major;
  96 #define PARTITION_SHIFT 3
  97
  98 static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr)
  99 {
 100         return vio_dring_avail(dr, VDC_TX_RING_SIZE);
 101 }
 102
 103 static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 104 {
 105         struct gendisk *disk = bdev->bd_disk;
 106         struct vdc_port *port = disk->private_data;
 107
 108         geo->heads = (u8) port->geom.num_hd;
 109         geo->sectors = (u8) port->geom.num_sec;
 110         geo->cylinders = port->geom.num_cyl;
 111
 112         return 0;
 113 }
 114
 115 /* Add ioctl/CDROM_GET_CAPABILITY to support cdrom_id in udev
 116  * when vdisk_mtype is VD_MEDIA_TYPE_CD or VD_MEDIA_TYPE_DVD.
 117  * Needed to be able to install inside an ldom from an iso image.
 118  */
 119 static int vdc_ioctl(struct block_device *bdev, fmode_t mode,
 120                      unsigned command, unsigned long argument)
 121 {
 122         int i;
 123         struct gendisk *disk;
 124
 125         switch (command) {
 126         case CDROMMULTISESSION:
 127                 pr_debug(PFX "Multisession CDs not supported\n");
 128                 for (i = 0; i < sizeof(struct cdrom_multisession); i++)
 129                         if (put_user(0, (char __user *)(argument + i)))
 130                                 return -EFAULT;
 131                 return 0;
 132
 133         case CDROM_GET_CAPABILITY:
 134                 disk = bdev->bd_disk;
 135
 136                 if (bdev->bd_disk && (disk->flags & GENHD_FL_CD))
 137                         return 0;
 138                 return -EINVAL;
 139
 140         default:
 141                 pr_debug(PFX "ioctl %08x not supported\n", command);
 142                 return -EINVAL;
 143         }
 144 }
 145
 146 static const struct block_device_operations vdc_fops = {
 147         .owner          = THIS_MODULE,
 148         .getgeo         = vdc_getgeo,
 149         .ioctl          = vdc_ioctl,
 150 };
 151
 152 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)
 153 {
 154         if (vio->cmp &&
 155             (waiting_for == -1 ||
 156              vio->cmp->waiting_for == waiting_for)) {
 157                 vio->cmp->err = err;
 158                 complete(&vio->cmp->com);
 159                 vio->cmp = NULL;
 160         }
 161 }
 162
 163 static void vdc_handshake_complete(struct vio_driver_state *vio)
 164 {
 165         vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
 166 }
 167
 168 static int vdc_handle_unknown(struct vdc_port *port, void *arg)
 169 {
 170         struct vio_msg_tag *pkt = arg;
 171
 172         printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n",
 173                pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
 174         printk(KERN_ERR PFX "Resetting connection.\n");
 175
 176         ldc_disconnect(port->vio.lp);
 177
 178         return -ECONNRESET;
 179 }
 180
 181 static int vdc_send_attr(struct vio_driver_state *vio)
 182 {
 183         struct vdc_port *port = to_vdc_port(vio);
 184         struct vio_disk_attr_info pkt;
 185
 186         memset(&pkt, 0, sizeof(pkt));
 187
 188         pkt.tag.type = VIO_TYPE_CTRL;
 189         pkt.tag.stype = VIO_SUBTYPE_INFO;
 190         pkt.tag.stype_env = VIO_ATTR_INFO;
 191         pkt.tag.sid = vio_send_sid(vio);
 192
 193         pkt.xfer_mode = VIO_DRING_MODE;
 194         pkt.vdisk_block_size = port->vdisk_block_size;
 195         pkt.max_xfer_size = port->max_xfer_size;
 196
 197         viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
 198                pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size);
 199
 200         return vio_ldc_send(&port->vio, &pkt, sizeof(pkt));
 201 }
 202
 203 static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
 204 {
 205         struct vdc_port *port = to_vdc_port(vio);
 206         struct vio_disk_attr_info *pkt = arg;
 207
 208         viodbg(HS, "GOT ATTR stype[0x%x] ops[%llx] disk_size[%llu] disk_type[%x] "
 209                "mtype[0x%x] xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
 210                pkt->tag.stype, pkt->operations,
 211                pkt->vdisk_size, pkt->vdisk_type, pkt->vdisk_mtype,
 212                pkt->xfer_mode, pkt->vdisk_block_size,
 213                pkt->max_xfer_size);
 214
 215         if (pkt->tag.stype == VIO_SUBTYPE_ACK) {
 216                 switch (pkt->vdisk_type) {
 217                 case VD_DISK_TYPE_DISK:
 218                 case VD_DISK_TYPE_SLICE:
 219                         break;
 220
 221                 default:
 222                         printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n",
 223                                vio->name, pkt->vdisk_type);
 224                         return -ECONNRESET;
 225                 }
 226
 227                 if (pkt->vdisk_block_size > port->vdisk_block_size) {
 228                         printk(KERN_ERR PFX "%s: BLOCK size increased "
 229                                "%u --> %u\n",
 230                                vio->name,
 231                                port->vdisk_block_size, pkt->vdisk_block_size);
 232                         return -ECONNRESET;
 233                 }
 234
 235                 port->operations = pkt->operations;
 236                 port->vdisk_type = pkt->vdisk_type;
 237                 if (vdc_version_supported(port, 1, 1)) {
 238                         port->vdisk_size = pkt->vdisk_size;
 239                         port->vdisk_mtype = pkt->vdisk_mtype;
 240                 }
 241                 if (pkt->max_xfer_size < port->max_xfer_size)
 242                         port->max_xfer_size = pkt->max_xfer_size;
 243                 port->vdisk_block_size = pkt->vdisk_block_size;
 244                 return 0;
 245         } else {
 246                 printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name);
 247
 248                 return -ECONNRESET;
 249         }
 250 }
 251
 252 static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc)
 253 {
 254         int err = desc->status;
 255
 256         vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD);
 257 }
 258
 259 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
 260                         unsigned int index)
 261 {
 262         struct vio_disk_desc *desc = vio_dring_entry(dr, index);
 263         struct vdc_req_entry *rqe = &port->rq_arr[index];
 264         struct request *req;
 265
 266         if (unlikely(desc->hdr.state != VIO_DESC_DONE))
 267                 return;
 268
 269         ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
 270         desc->hdr.state = VIO_DESC_FREE;
 271         dr->cons = (index + 1) & (VDC_TX_RING_SIZE - 1);
 272
 273         req = rqe->req;
 274         if (req == NULL) {
 275                 vdc_end_special(port, desc);
 276                 return;
 277         }
 278
 279         rqe->req = NULL;
 280
 281         __blk_end_request(req, (desc->status ? -EIO : 0), desc->size);
 282
 283         if (blk_queue_stopped(port->disk->queue))
 284                 blk_start_queue(port->disk->queue);
 285 }
 286
 287 static int vdc_ack(struct vdc_port *port, void *msgbuf)
 288 {
 289         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 290         struct vio_dring_data *pkt = msgbuf;
 291
 292         if (unlikely(pkt->dring_ident != dr->ident ||
 293                      pkt->start_idx != pkt->end_idx ||
 294                      pkt->start_idx >= VDC_TX_RING_SIZE))
 295                 return 0;
 296
 297         vdc_end_one(port, dr, pkt->start_idx);
 298
 299         return 0;
 300 }
 301
 302 static int vdc_nack(struct vdc_port *port, void *msgbuf)
 303 {
 304         /* XXX Implement me XXX */
 305         return 0;
 306 }
 307
 308 static void vdc_event(void *arg, int event)
 309 {
 310         struct vdc_port *port = arg;
 311         struct vio_driver_state *vio = &port->vio;
 312         unsigned long flags;
 313         int err;
 314
 315         spin_lock_irqsave(&vio->lock, flags);
 316
 317         if (unlikely(event == LDC_EVENT_RESET ||
 318                      event == LDC_EVENT_UP)) {
 319                 vio_link_state_change(vio, event);
 320                 spin_unlock_irqrestore(&vio->lock, flags);
 321                 return;
 322         }
 323
 324         if (unlikely(event != LDC_EVENT_DATA_READY)) {
 325                 printk(KERN_WARNING PFX "Unexpected LDC event %d\n", event);
 326                 spin_unlock_irqrestore(&vio->lock, flags);
 327                 return;
 328         }
 329
 330         err = 0;
 331         while (1) {
 332                 union {
 333                         struct vio_msg_tag tag;
 334                         u64 raw[8];
 335                 } msgbuf;
 336
 337                 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
 338                 if (unlikely(err < 0)) {
 339                         if (err == -ECONNRESET)
 340                                 vio_conn_reset(vio);
 341                         break;
 342                 }
 343                 if (err == 0)
 344                         break;
 345                 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
 346                        msgbuf.tag.type,
 347                        msgbuf.tag.stype,
 348                        msgbuf.tag.stype_env,
 349                        msgbuf.tag.sid);
 350                 err = vio_validate_sid(vio, &msgbuf.tag);
 351                 if (err < 0)
 352                         break;
 353
 354                 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
 355                         if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
 356                                 err = vdc_ack(port, &msgbuf);
 357                         else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
 358                                 err = vdc_nack(port, &msgbuf);
 359                         else
 360                                 err = vdc_handle_unknown(port, &msgbuf);
 361                 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
 362                         err = vio_control_pkt_engine(vio, &msgbuf);
 363                 } else {
 364                         err = vdc_handle_unknown(port, &msgbuf);
 365                 }
 366                 if (err < 0)
 367                         break;
 368         }
 369         if (err < 0)
 370                 vdc_finish(&port->vio, err, WAITING_FOR_ANY);
 371         spin_unlock_irqrestore(&vio->lock, flags);
 372 }
 373
 374 static int __vdc_tx_trigger(struct vdc_port *port)
 375 {
 376         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 377         struct vio_dring_data hdr = {
 378                 .tag = {
 379                         .type           = VIO_TYPE_DATA,
 380                         .stype          = VIO_SUBTYPE_INFO,
 381                         .stype_env      = VIO_DRING_DATA,
 382                         .sid            = vio_send_sid(&port->vio),
 383                 },
 384                 .dring_ident            = dr->ident,
 385                 .start_idx              = dr->prod,
 386                 .end_idx                = dr->prod,
 387         };
 388         int err, delay;
 389
 390         hdr.seq = dr->snd_nxt;
 391         delay = 1;
 392         do {
 393                 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
 394                 if (err > 0) {
 395                         dr->snd_nxt++;
 396                         break;
 397                 }
 398                 udelay(delay);
 399                 if ((delay <<= 1) > 128)
 400                         delay = 128;
 401         } while (err == -EAGAIN);
 402
 403         return err;
 404 }
 405
 406 static int __send_request(struct request *req)
 407 {
 408         struct vdc_port *port = req->rq_disk->private_data;
 409         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 410         struct scatterlist sg[port->ring_cookies];
 411         struct vdc_req_entry *rqe;
 412         struct vio_disk_desc *desc;
 413         unsigned int map_perm;
 414         int nsg, err, i;
 415         u64 len;
 416         u8 op;
 417
 418         map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 419
 420         if (rq_data_dir(req) == READ) {
 421                 map_perm |= LDC_MAP_W;
 422                 op = VD_OP_BREAD;
 423         } else {
 424                 map_perm |= LDC_MAP_R;
 425                 op = VD_OP_BWRITE;
 426         }
 427
 428         sg_init_table(sg, port->ring_cookies);
 429         nsg = blk_rq_map_sg(req->q, req, sg);
 430
 431         len = 0;
 432         for (i = 0; i < nsg; i++)
 433                 len += sg[i].length;
 434
 435         if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
 436                 blk_stop_queue(port->disk->queue);
 437                 err = -ENOMEM;
 438                 goto out;
 439         }
 440
 441         desc = vio_dring_cur(dr);
 442
 443         err = ldc_map_sg(port->vio.lp, sg, nsg,
 444                          desc->cookies, port->ring_cookies,
 445                          map_perm);
 446         if (err < 0) {
 447                 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
 448                 return err;
 449         }
 450
 451         rqe = &port->rq_arr[dr->prod];
 452         rqe->req = req;
 453
 454         desc->hdr.ack = VIO_ACK_ENABLE;
 455         desc->req_id = port->req_id;
 456         desc->operation = op;
 457         if (port->vdisk_type == VD_DISK_TYPE_DISK) {
 458                 desc->slice = 0xff;
 459         } else {
 460                 desc->slice = 0;
 461         }
 462         desc->status = ~0;
 463         desc->offset = (blk_rq_pos(req) << 9) / port->vdisk_block_size;
 464         desc->size = len;
 465         desc->ncookies = err;
 466
 467         /* This has to be a non-SMP write barrier because we are writing
 468          * to memory which is shared with the peer LDOM.
 469          */
 470         wmb();
 471         desc->hdr.state = VIO_DESC_READY;
 472
 473         err = __vdc_tx_trigger(port);
 474         if (err < 0) {
 475                 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
 476         } else {
 477                 port->req_id++;
 478                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
 479         }
 480 out:
 481
 482         return err;
 483 }
 484
 485 static void do_vdc_request(struct request_queue *q)
 486 {
 487         while (1) {
 488                 struct request *req = blk_fetch_request(q);
 489
 490                 if (!req)
 491                         break;
 492
 493                 if (__send_request(req) < 0)
 494                         __blk_end_request_all(req, -EIO);
 495         }
 496 }
 497
 498 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
 499 {
 500         struct vio_dring_state *dr;
 501         struct vio_completion comp;
 502         struct vio_disk_desc *desc;
 503         unsigned int map_perm;
 504         unsigned long flags;
 505         int op_len, err;
 506         void *req_buf;
 507
 508         if (!(((u64)1 << (u64)op) & port->operations))
 509                 return -EOPNOTSUPP;
 510
 511         switch (op) {
 512         case VD_OP_BREAD:
 513         case VD_OP_BWRITE:
 514         default:
 515                 return -EINVAL;
 516
 517         case VD_OP_FLUSH:
 518                 op_len = 0;
 519                 map_perm = 0;
 520                 break;
 521
 522         case VD_OP_GET_WCE:
 523                 op_len = sizeof(u32);
 524                 map_perm = LDC_MAP_W;
 525                 break;
 526
 527         case VD_OP_SET_WCE:
 528                 op_len = sizeof(u32);
 529                 map_perm = LDC_MAP_R;
 530                 break;
 531
 532         case VD_OP_GET_VTOC:
 533                 op_len = sizeof(struct vio_disk_vtoc);
 534                 map_perm = LDC_MAP_W;
 535                 break;
 536
 537         case VD_OP_SET_VTOC:
 538                 op_len = sizeof(struct vio_disk_vtoc);
 539                 map_perm = LDC_MAP_R;
 540                 break;
 541
 542         case VD_OP_GET_DISKGEOM:
 543                 op_len = sizeof(struct vio_disk_geom);
 544                 map_perm = LDC_MAP_W;
 545                 break;
 546
 547         case VD_OP_SET_DISKGEOM:
 548                 op_len = sizeof(struct vio_disk_geom);
 549                 map_perm = LDC_MAP_R;
 550                 break;
 551
 552         case VD_OP_SCSICMD:
 553                 op_len = 16;
 554                 map_perm = LDC_MAP_RW;
 555                 break;
 556
 557         case VD_OP_GET_DEVID:
 558                 op_len = sizeof(struct vio_disk_devid);
 559                 map_perm = LDC_MAP_W;
 560                 break;
 561
 562         case VD_OP_GET_EFI:
 563         case VD_OP_SET_EFI:
 564                 return -EOPNOTSUPP;
 565                 break;
 566         };
 567
 568         map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 569
 570         op_len = (op_len + 7) & ~7;
 571         req_buf = kzalloc(op_len, GFP_KERNEL);
 572         if (!req_buf)
 573                 return -ENOMEM;
 574
 575         if (len > op_len)
 576                 len = op_len;
 577
 578         if (map_perm & LDC_MAP_R)
 579                 memcpy(req_buf, buf, len);
 580
 581         spin_lock_irqsave(&port->vio.lock, flags);
 582
 583         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 584
 585         /* XXX If we want to use this code generically we have to
 586          * XXX handle TX ring exhaustion etc.
 587          */
 588         desc = vio_dring_cur(dr);
 589
 590         err = ldc_map_single(port->vio.lp, req_buf, op_len,
 591                              desc->cookies, port->ring_cookies,
 592                              map_perm);
 593         if (err < 0) {
 594                 spin_unlock_irqrestore(&port->vio.lock, flags);
 595                 kfree(req_buf);
 596                 return err;
 597         }
 598
 599         init_completion(&comp.com);
 600         comp.waiting_for = WAITING_FOR_GEN_CMD;
 601         port->vio.cmp = &comp;
 602
 603         desc->hdr.ack = VIO_ACK_ENABLE;
 604         desc->req_id = port->req_id;
 605         desc->operation = op;
 606         desc->slice = 0;
 607         desc->status = ~0;
 608         desc->offset = 0;
 609         desc->size = op_len;
 610         desc->ncookies = err;
 611
 612         /* This has to be a non-SMP write barrier because we are writing
 613          * to memory which is shared with the peer LDOM.
 614          */
 615         wmb();
 616         desc->hdr.state = VIO_DESC_READY;
 617
 618         err = __vdc_tx_trigger(port);
 619         if (err >= 0) {
 620                 port->req_id++;
 621                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
 622                 spin_unlock_irqrestore(&port->vio.lock, flags);
 623
 624                 wait_for_completion(&comp.com);
 625                 err = comp.err;
 626         } else {
 627                 port->vio.cmp = NULL;
 628                 spin_unlock_irqrestore(&port->vio.lock, flags);
 629         }
 630
 631         if (map_perm & LDC_MAP_W)
 632                 memcpy(buf, req_buf, len);
 633
 634         kfree(req_buf);
 635
 636         return err;
 637 }
 638
 639 static int vdc_alloc_tx_ring(struct vdc_port *port)
 640 {
 641         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 642         unsigned long len, entry_size;
 643         int ncookies;
 644         void *dring;
 645
 646         entry_size = sizeof(struct vio_disk_desc) +
 647                 (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
 648         len = (VDC_TX_RING_SIZE * entry_size);
 649
 650         ncookies = VIO_MAX_RING_COOKIES;
 651         dring = ldc_alloc_exp_dring(port->vio.lp, len,
 652                                     dr->cookies, &ncookies,
 653                                     (LDC_MAP_SHADOW |
 654                                      LDC_MAP_DIRECT |
 655                                      LDC_MAP_RW));
 656         if (IS_ERR(dring))
 657                 return PTR_ERR(dring);
 658
 659         dr->base = dring;
 660         dr->entry_size = entry_size;
 661         dr->num_entries = VDC_TX_RING_SIZE;
 662         dr->prod = dr->cons = 0;
 663         dr->pending = VDC_TX_RING_SIZE;
 664         dr->ncookies = ncookies;
 665
 666         return 0;
 667 }
 668
 669 static void vdc_free_tx_ring(struct vdc_port *port)
 670 {
 671         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 672
 673         if (dr->base) {
 674                 ldc_free_exp_dring(port->vio.lp, dr->base,
 675                                    (dr->entry_size * dr->num_entries),
 676                                    dr->cookies, dr->ncookies);
 677                 dr->base = NULL;
 678                 dr->entry_size = 0;
 679                 dr->num_entries = 0;
 680                 dr->pending = 0;
 681                 dr->ncookies = 0;
 682         }
 683 }
 684
 685 static int probe_disk(struct vdc_port *port)
 686 {
 687         struct vio_completion comp;
 688         struct request_queue *q;
 689         struct gendisk *g;
 690         int err;
 691
 692         init_completion(&comp.com);
 693         comp.err = 0;
 694         comp.waiting_for = WAITING_FOR_LINK_UP;
 695         port->vio.cmp = &comp;
 696
 697         vio_port_up(&port->vio);
 698
 699         wait_for_completion(&comp.com);
 700         if (comp.err)
 701                 return comp.err;
 702
 703         err = generic_request(port, VD_OP_GET_VTOC,
 704                               &port->label, sizeof(port->label));
 705         if (err < 0) {
 706                 printk(KERN_ERR PFX "VD_OP_GET_VTOC returns error %d\n", err);
 707                 return err;
 708         }
 709
 710         if (vdc_version_supported(port, 1, 1)) {
 711                 /* vdisk_size should be set during the handshake, if it wasn't
 712                  * then the underlying disk is reserved by another system
 713                  */
 714                 if (port->vdisk_size == -1)
 715                         return -ENODEV;
 716         } else {
 717                 err = generic_request(port, VD_OP_GET_DISKGEOM,
 718                                       &port->geom, sizeof(port->geom));
 719                 if (err < 0) {
 720                         printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
 721                                "error %d\n", err);
 722                         return err;
 723                 }
 724                 port->vdisk_size = ((u64)port->geom.num_cyl *
 725                                     (u64)port->geom.num_hd *
 726                                     (u64)port->geom.num_sec);
 727         }
 728
 729         q = blk_init_queue(do_vdc_request, &port->vio.lock);
 730         if (!q) {
 731                 printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
 732                        port->vio.name);
 733                 return -ENOMEM;
 734         }
 735         g = alloc_disk(1 << PARTITION_SHIFT);
 736         if (!g) {
 737                 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
 738                        port->vio.name);
 739                 blk_cleanup_queue(q);
 740                 return -ENOMEM;
 741         }
 742
 743         port->disk = g;
 744
 745         blk_queue_max_segments(q, port->ring_cookies);
 746         blk_queue_max_hw_sectors(q, port->max_xfer_size);
 747         g->major = vdc_major;
 748         g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
 749         strcpy(g->disk_name, port->disk_name);
 750
 751         g->fops = &vdc_fops;
 752         g->queue = q;
 753         g->private_data = port;
 754         g->driverfs_dev = &port->vio.vdev->dev;
 755
 756         set_capacity(g, port->vdisk_size);
 757
 758         if (vdc_version_supported(port, 1, 1)) {
 759                 switch (port->vdisk_mtype) {
 760                 case VD_MEDIA_TYPE_CD:
 761                         pr_info(PFX "Virtual CDROM %s\n", port->disk_name);
 762                         g->flags |= GENHD_FL_CD;
 763                         g->flags |= GENHD_FL_REMOVABLE;
 764                         set_disk_ro(g, 1);
 765                         break;
 766
 767                 case VD_MEDIA_TYPE_DVD:
 768                         pr_info(PFX "Virtual DVD %s\n", port->disk_name);
 769                         g->flags |= GENHD_FL_CD;
 770                         g->flags |= GENHD_FL_REMOVABLE;
 771                         set_disk_ro(g, 1);
 772                         break;
 773
 774                 case VD_MEDIA_TYPE_FIXED:
 775                         pr_info(PFX "Virtual Hard disk %s\n", port->disk_name);
 776                         break;
 777                 }
 778         }
 779
 780         pr_info(PFX "%s: %u sectors (%u MB) protocol %d.%d\n",
 781                g->disk_name,
 782                port->vdisk_size, (port->vdisk_size >> (20 - 9)),
 783                port->vio.ver.major, port->vio.ver.minor);
 784
 785         add_disk(g);
 786
 787         return 0;
 788 }
 789
 790 static struct ldc_channel_config vdc_ldc_cfg = {
 791         .event          = vdc_event,
 792         .mtu            = 64,
 793         .mode           = LDC_MODE_UNRELIABLE,
 794 };
 795
 796 static struct vio_driver_ops vdc_vio_ops = {
 797         .send_attr              = vdc_send_attr,
 798         .handle_attr            = vdc_handle_attr,
 799         .handshake_complete     = vdc_handshake_complete,
 800 };
 801
 802 static void print_version(void)
 803 {
 804         static int version_printed;
 805
 806         if (version_printed++ == 0)
 807                 printk(KERN_INFO "%s", version);
 808 }
 809
 810 static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 811 {
 812         struct mdesc_handle *hp;
 813         struct vdc_port *port;
 814         int err;
 815
 816         print_version();
 817
 818         hp = mdesc_grab();
 819
 820         err = -ENODEV;
 821         if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
 822                 printk(KERN_ERR PFX "Port id [%llu] too large.\n",
 823                        vdev->dev_no);
 824                 goto err_out_release_mdesc;
 825         }
 826
 827         port = kzalloc(sizeof(*port), GFP_KERNEL);
 828         err = -ENOMEM;
 829         if (!port) {
 830                 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
 831                 goto err_out_release_mdesc;
 832         }
 833
 834         if (vdev->dev_no >= 26)
 835                 snprintf(port->disk_name, sizeof(port->disk_name),
 836                          VDCBLK_NAME "%c%c",
 837                          'a' + ((int)vdev->dev_no / 26) - 1,
 838                          'a' + ((int)vdev->dev_no % 26));
 839         else
 840                 snprintf(port->disk_name, sizeof(port->disk_name),
 841                          VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
 842         port->vdisk_size = -1;
 843
 844         err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
 845                               vdc_versions, ARRAY_SIZE(vdc_versions),
 846                               &vdc_vio_ops, port->disk_name);
 847         if (err)
 848                 goto err_out_free_port;
 849
 850         port->vdisk_block_size = 512;
 851         port->max_xfer_size = ((128 * 1024) / port->vdisk_block_size);
 852         port->ring_cookies = ((port->max_xfer_size *
 853                                port->vdisk_block_size) / PAGE_SIZE) + 2;
 854
 855         err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
 856         if (err)
 857                 goto err_out_free_port;
 858
 859         err = vdc_alloc_tx_ring(port);
 860         if (err)
 861                 goto err_out_free_ldc;
 862
 863         err = probe_disk(port);
 864         if (err)
 865                 goto err_out_free_tx_ring;
 866
 867         dev_set_drvdata(&vdev->dev, port);
 868
 869         mdesc_release(hp);
 870
 871         return 0;
 872
 873 err_out_free_tx_ring:
 874         vdc_free_tx_ring(port);
 875
 876 err_out_free_ldc:
 877         vio_ldc_free(&port->vio);
 878
 879 err_out_free_port:
 880         kfree(port);
 881
 882 err_out_release_mdesc:
 883         mdesc_release(hp);
 884         return err;
 885 }
 886
 887 static int vdc_port_remove(struct vio_dev *vdev)
 888 {
 889         struct vdc_port *port = dev_get_drvdata(&vdev->dev);
 890
 891         if (port) {
 892                 del_timer_sync(&port->vio.timer);
 893
 894                 vdc_free_tx_ring(port);
 895                 vio_ldc_free(&port->vio);
 896
 897                 dev_set_drvdata(&vdev->dev, NULL);
 898
 899                 kfree(port);
 900         }
 901         return 0;
 902 }
 903
 904 static const struct vio_device_id vdc_port_match[] = {
 905         {
 906                 .type = "vdc-port",
 907         },
 908         {},
 909 };
 910 MODULE_DEVICE_TABLE(vio, vdc_port_match);
 911
 912 static struct vio_driver vdc_port_driver = {
 913         .id_table       = vdc_port_match,
 914         .probe          = vdc_port_probe,
 915         .remove         = vdc_port_remove,
 916         .name           = "vdc_port",
 917 };
 918
 919 static int __init vdc_init(void)
 920 {
 921         int err;
 922
 923         err = register_blkdev(0, VDCBLK_NAME);
 924         if (err < 0)
 925                 goto out_err;
 926
 927         vdc_major = err;
 928
 929         err = vio_register_driver(&vdc_port_driver);
 930         if (err)
 931                 goto out_unregister_blkdev;
 932
 933         return 0;
 934
 935 out_unregister_blkdev:
 936         unregister_blkdev(vdc_major, VDCBLK_NAME);
 937         vdc_major = 0;
 938
 939 out_err:
 940         return err;
 941 }
 942
 943 static void __exit vdc_exit(void)
 944 {
 945         vio_unregister_driver(&vdc_port_driver);
 946         unregister_blkdev(vdc_major, VDCBLK_NAME);
 947 }
 948
 949 module_init(vdc_init);
 950 module_exit(vdc_exit);