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_vtoc    label;
  74 };
  75
  76 static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
  77 {
  78         return container_of(vio, struct vdc_port, vio);
  79 }
  80
  81 /* Ordered from largest major to lowest */
  82 static struct vio_version vdc_versions[] = {
  83         { .major = 1, .minor = 1 },
  84         { .major = 1, .minor = 0 },
  85 };
  86
  87 static inline int vdc_version_supported(struct vdc_port *port,
  88                                         u16 major, u16 minor)
  89 {
  90         return port->vio.ver.major == major && port->vio.ver.minor >= minor;
  91 }
  92
  93 #define VDCBLK_NAME     "vdisk"
  94 static int vdc_major;
  95 #define PARTITION_SHIFT 3
  96
  97 static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr)
  98 {
  99         return vio_dring_avail(dr, VDC_TX_RING_SIZE);
 100 }
 101
 102 static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 103 {
 104         struct gendisk *disk = bdev->bd_disk;
 105         sector_t nsect = get_capacity(disk);
 106         sector_t cylinders = nsect;
 107
 108         geo->heads = 0xff;
 109         geo->sectors = 0x3f;
 110         sector_div(cylinders, geo->heads * geo->sectors);
 111         geo->cylinders = cylinders;
 112         if ((sector_t)(geo->cylinders + 1) * geo->heads * geo->sectors < nsect)
 113                 geo->cylinders = 0xffff;
 114
 115         return 0;
 116 }
 117
 118 /* Add ioctl/CDROM_GET_CAPABILITY to support cdrom_id in udev
 119  * when vdisk_mtype is VD_MEDIA_TYPE_CD or VD_MEDIA_TYPE_DVD.
 120  * Needed to be able to install inside an ldom from an iso image.
 121  */
 122 static int vdc_ioctl(struct block_device *bdev, fmode_t mode,
 123                      unsigned command, unsigned long argument)
 124 {
 125         int i;
 126         struct gendisk *disk;
 127
 128         switch (command) {
 129         case CDROMMULTISESSION:
 130                 pr_debug(PFX "Multisession CDs not supported\n");
 131                 for (i = 0; i < sizeof(struct cdrom_multisession); i++)
 132                         if (put_user(0, (char __user *)(argument + i)))
 133                                 return -EFAULT;
 134                 return 0;
 135
 136         case CDROM_GET_CAPABILITY:
 137                 disk = bdev->bd_disk;
 138
 139                 if (bdev->bd_disk && (disk->flags & GENHD_FL_CD))
 140                         return 0;
 141                 return -EINVAL;
 142
 143         default:
 144                 pr_debug(PFX "ioctl %08x not supported\n", command);
 145                 return -EINVAL;
 146         }
 147 }
 148
 149 static const struct block_device_operations vdc_fops = {
 150         .owner          = THIS_MODULE,
 151         .getgeo         = vdc_getgeo,
 152         .ioctl          = vdc_ioctl,
 153 };
 154
 155 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)
 156 {
 157         if (vio->cmp &&
 158             (waiting_for == -1 ||
 159              vio->cmp->waiting_for == waiting_for)) {
 160                 vio->cmp->err = err;
 161                 complete(&vio->cmp->com);
 162                 vio->cmp = NULL;
 163         }
 164 }
 165
 166 static void vdc_handshake_complete(struct vio_driver_state *vio)
 167 {
 168         vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
 169 }
 170
 171 static int vdc_handle_unknown(struct vdc_port *port, void *arg)
 172 {
 173         struct vio_msg_tag *pkt = arg;
 174
 175         printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n",
 176                pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
 177         printk(KERN_ERR PFX "Resetting connection.\n");
 178
 179         ldc_disconnect(port->vio.lp);
 180
 181         return -ECONNRESET;
 182 }
 183
 184 static int vdc_send_attr(struct vio_driver_state *vio)
 185 {
 186         struct vdc_port *port = to_vdc_port(vio);
 187         struct vio_disk_attr_info pkt;
 188
 189         memset(&pkt, 0, sizeof(pkt));
 190
 191         pkt.tag.type = VIO_TYPE_CTRL;
 192         pkt.tag.stype = VIO_SUBTYPE_INFO;
 193         pkt.tag.stype_env = VIO_ATTR_INFO;
 194         pkt.tag.sid = vio_send_sid(vio);
 195
 196         pkt.xfer_mode = VIO_DRING_MODE;
 197         pkt.vdisk_block_size = port->vdisk_block_size;
 198         pkt.max_xfer_size = port->max_xfer_size;
 199
 200         viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
 201                pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size);
 202
 203         return vio_ldc_send(&port->vio, &pkt, sizeof(pkt));
 204 }
 205
 206 static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
 207 {
 208         struct vdc_port *port = to_vdc_port(vio);
 209         struct vio_disk_attr_info *pkt = arg;
 210
 211         viodbg(HS, "GOT ATTR stype[0x%x] ops[%llx] disk_size[%llu] disk_type[%x] "
 212                "mtype[0x%x] xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
 213                pkt->tag.stype, pkt->operations,
 214                pkt->vdisk_size, pkt->vdisk_type, pkt->vdisk_mtype,
 215                pkt->xfer_mode, pkt->vdisk_block_size,
 216                pkt->max_xfer_size);
 217
 218         if (pkt->tag.stype == VIO_SUBTYPE_ACK) {
 219                 switch (pkt->vdisk_type) {
 220                 case VD_DISK_TYPE_DISK:
 221                 case VD_DISK_TYPE_SLICE:
 222                         break;
 223
 224                 default:
 225                         printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n",
 226                                vio->name, pkt->vdisk_type);
 227                         return -ECONNRESET;
 228                 }
 229
 230                 if (pkt->vdisk_block_size > port->vdisk_block_size) {
 231                         printk(KERN_ERR PFX "%s: BLOCK size increased "
 232                                "%u --> %u\n",
 233                                vio->name,
 234                                port->vdisk_block_size, pkt->vdisk_block_size);
 235                         return -ECONNRESET;
 236                 }
 237
 238                 port->operations = pkt->operations;
 239                 port->vdisk_type = pkt->vdisk_type;
 240                 if (vdc_version_supported(port, 1, 1)) {
 241                         port->vdisk_size = pkt->vdisk_size;
 242                         port->vdisk_mtype = pkt->vdisk_mtype;
 243                 }
 244                 if (pkt->max_xfer_size < port->max_xfer_size)
 245                         port->max_xfer_size = pkt->max_xfer_size;
 246                 port->vdisk_block_size = pkt->vdisk_block_size;
 247                 return 0;
 248         } else {
 249                 printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name);
 250
 251                 return -ECONNRESET;
 252         }
 253 }
 254
 255 static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc)
 256 {
 257         int err = desc->status;
 258
 259         vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD);
 260 }
 261
 262 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
 263                         unsigned int index)
 264 {
 265         struct vio_disk_desc *desc = vio_dring_entry(dr, index);
 266         struct vdc_req_entry *rqe = &port->rq_arr[index];
 267         struct request *req;
 268
 269         if (unlikely(desc->hdr.state != VIO_DESC_DONE))
 270                 return;
 271
 272         ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
 273         desc->hdr.state = VIO_DESC_FREE;
 274         dr->cons = (index + 1) & (VDC_TX_RING_SIZE - 1);
 275
 276         req = rqe->req;
 277         if (req == NULL) {
 278                 vdc_end_special(port, desc);
 279                 return;
 280         }
 281
 282         rqe->req = NULL;
 283
 284         __blk_end_request(req, (desc->status ? -EIO : 0), desc->size);
 285
 286         if (blk_queue_stopped(port->disk->queue))
 287                 blk_start_queue(port->disk->queue);
 288 }
 289
 290 static int vdc_ack(struct vdc_port *port, void *msgbuf)
 291 {
 292         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 293         struct vio_dring_data *pkt = msgbuf;
 294
 295         if (unlikely(pkt->dring_ident != dr->ident ||
 296                      pkt->start_idx != pkt->end_idx ||
 297                      pkt->start_idx >= VDC_TX_RING_SIZE))
 298                 return 0;
 299
 300         vdc_end_one(port, dr, pkt->start_idx);
 301
 302         return 0;
 303 }
 304
 305 static int vdc_nack(struct vdc_port *port, void *msgbuf)
 306 {
 307         /* XXX Implement me XXX */
 308         return 0;
 309 }
 310
 311 static void vdc_event(void *arg, int event)
 312 {
 313         struct vdc_port *port = arg;
 314         struct vio_driver_state *vio = &port->vio;
 315         unsigned long flags;
 316         int err;
 317
 318         spin_lock_irqsave(&vio->lock, flags);
 319
 320         if (unlikely(event == LDC_EVENT_RESET ||
 321                      event == LDC_EVENT_UP)) {
 322                 vio_link_state_change(vio, event);
 323                 spin_unlock_irqrestore(&vio->lock, flags);
 324                 return;
 325         }
 326
 327         if (unlikely(event != LDC_EVENT_DATA_READY)) {
 328                 printk(KERN_WARNING PFX "Unexpected LDC event %d\n", event);
 329                 spin_unlock_irqrestore(&vio->lock, flags);
 330                 return;
 331         }
 332
 333         err = 0;
 334         while (1) {
 335                 union {
 336                         struct vio_msg_tag tag;
 337                         u64 raw[8];
 338                 } msgbuf;
 339
 340                 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
 341                 if (unlikely(err < 0)) {
 342                         if (err == -ECONNRESET)
 343                                 vio_conn_reset(vio);
 344                         break;
 345                 }
 346                 if (err == 0)
 347                         break;
 348                 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
 349                        msgbuf.tag.type,
 350                        msgbuf.tag.stype,
 351                        msgbuf.tag.stype_env,
 352                        msgbuf.tag.sid);
 353                 err = vio_validate_sid(vio, &msgbuf.tag);
 354                 if (err < 0)
 355                         break;
 356
 357                 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
 358                         if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
 359                                 err = vdc_ack(port, &msgbuf);
 360                         else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
 361                                 err = vdc_nack(port, &msgbuf);
 362                         else
 363                                 err = vdc_handle_unknown(port, &msgbuf);
 364                 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
 365                         err = vio_control_pkt_engine(vio, &msgbuf);
 366                 } else {
 367                         err = vdc_handle_unknown(port, &msgbuf);
 368                 }
 369                 if (err < 0)
 370                         break;
 371         }
 372         if (err < 0)
 373                 vdc_finish(&port->vio, err, WAITING_FOR_ANY);
 374         spin_unlock_irqrestore(&vio->lock, flags);
 375 }
 376
 377 static int __vdc_tx_trigger(struct vdc_port *port)
 378 {
 379         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 380         struct vio_dring_data hdr = {
 381                 .tag = {
 382                         .type           = VIO_TYPE_DATA,
 383                         .stype          = VIO_SUBTYPE_INFO,
 384                         .stype_env      = VIO_DRING_DATA,
 385                         .sid            = vio_send_sid(&port->vio),
 386                 },
 387                 .dring_ident            = dr->ident,
 388                 .start_idx              = dr->prod,
 389                 .end_idx                = dr->prod,
 390         };
 391         int err, delay;
 392
 393         hdr.seq = dr->snd_nxt;
 394         delay = 1;
 395         do {
 396                 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
 397                 if (err > 0) {
 398                         dr->snd_nxt++;
 399                         break;
 400                 }
 401                 udelay(delay);
 402                 if ((delay <<= 1) > 128)
 403                         delay = 128;
 404         } while (err == -EAGAIN);
 405
 406         return err;
 407 }
 408
 409 static int __send_request(struct request *req)
 410 {
 411         struct vdc_port *port = req->rq_disk->private_data;
 412         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 413         struct scatterlist sg[port->ring_cookies];
 414         struct vdc_req_entry *rqe;
 415         struct vio_disk_desc *desc;
 416         unsigned int map_perm;
 417         int nsg, err, i;
 418         u64 len;
 419         u8 op;
 420
 421         map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 422
 423         if (rq_data_dir(req) == READ) {
 424                 map_perm |= LDC_MAP_W;
 425                 op = VD_OP_BREAD;
 426         } else {
 427                 map_perm |= LDC_MAP_R;
 428                 op = VD_OP_BWRITE;
 429         }
 430
 431         sg_init_table(sg, port->ring_cookies);
 432         nsg = blk_rq_map_sg(req->q, req, sg);
 433
 434         len = 0;
 435         for (i = 0; i < nsg; i++)
 436                 len += sg[i].length;
 437
 438         if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
 439                 blk_stop_queue(port->disk->queue);
 440                 err = -ENOMEM;
 441                 goto out;
 442         }
 443
 444         desc = vio_dring_cur(dr);
 445
 446         err = ldc_map_sg(port->vio.lp, sg, nsg,
 447                          desc->cookies, port->ring_cookies,
 448                          map_perm);
 449         if (err < 0) {
 450                 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
 451                 return err;
 452         }
 453
 454         rqe = &port->rq_arr[dr->prod];
 455         rqe->req = req;
 456
 457         desc->hdr.ack = VIO_ACK_ENABLE;
 458         desc->req_id = port->req_id;
 459         desc->operation = op;
 460         if (port->vdisk_type == VD_DISK_TYPE_DISK) {
 461                 desc->slice = 0xff;
 462         } else {
 463                 desc->slice = 0;
 464         }
 465         desc->status = ~0;
 466         desc->offset = (blk_rq_pos(req) << 9) / port->vdisk_block_size;
 467         desc->size = len;
 468         desc->ncookies = err;
 469
 470         /* This has to be a non-SMP write barrier because we are writing
 471          * to memory which is shared with the peer LDOM.
 472          */
 473         wmb();
 474         desc->hdr.state = VIO_DESC_READY;
 475
 476         err = __vdc_tx_trigger(port);
 477         if (err < 0) {
 478                 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
 479         } else {
 480                 port->req_id++;
 481                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
 482         }
 483 out:
 484
 485         return err;
 486 }
 487
 488 static void do_vdc_request(struct request_queue *q)
 489 {
 490         while (1) {
 491                 struct request *req = blk_fetch_request(q);
 492
 493                 if (!req)
 494                         break;
 495
 496                 if (__send_request(req) < 0)
 497                         __blk_end_request_all(req, -EIO);
 498         }
 499 }
 500
 501 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
 502 {
 503         struct vio_dring_state *dr;
 504         struct vio_completion comp;
 505         struct vio_disk_desc *desc;
 506         unsigned int map_perm;
 507         unsigned long flags;
 508         int op_len, err;
 509         void *req_buf;
 510
 511         if (!(((u64)1 << (u64)op) & port->operations))
 512                 return -EOPNOTSUPP;
 513
 514         switch (op) {
 515         case VD_OP_BREAD:
 516         case VD_OP_BWRITE:
 517         default:
 518                 return -EINVAL;
 519
 520         case VD_OP_FLUSH:
 521                 op_len = 0;
 522                 map_perm = 0;
 523                 break;
 524
 525         case VD_OP_GET_WCE:
 526                 op_len = sizeof(u32);
 527                 map_perm = LDC_MAP_W;
 528                 break;
 529
 530         case VD_OP_SET_WCE:
 531                 op_len = sizeof(u32);
 532                 map_perm = LDC_MAP_R;
 533                 break;
 534
 535         case VD_OP_GET_VTOC:
 536                 op_len = sizeof(struct vio_disk_vtoc);
 537                 map_perm = LDC_MAP_W;
 538                 break;
 539
 540         case VD_OP_SET_VTOC:
 541                 op_len = sizeof(struct vio_disk_vtoc);
 542                 map_perm = LDC_MAP_R;
 543                 break;
 544
 545         case VD_OP_GET_DISKGEOM:
 546                 op_len = sizeof(struct vio_disk_geom);
 547                 map_perm = LDC_MAP_W;
 548                 break;
 549
 550         case VD_OP_SET_DISKGEOM:
 551                 op_len = sizeof(struct vio_disk_geom);
 552                 map_perm = LDC_MAP_R;
 553                 break;
 554
 555         case VD_OP_SCSICMD:
 556                 op_len = 16;
 557                 map_perm = LDC_MAP_RW;
 558                 break;
 559
 560         case VD_OP_GET_DEVID:
 561                 op_len = sizeof(struct vio_disk_devid);
 562                 map_perm = LDC_MAP_W;
 563                 break;
 564
 565         case VD_OP_GET_EFI:
 566         case VD_OP_SET_EFI:
 567                 return -EOPNOTSUPP;
 568                 break;
 569         };
 570
 571         map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 572
 573         op_len = (op_len + 7) & ~7;
 574         req_buf = kzalloc(op_len, GFP_KERNEL);
 575         if (!req_buf)
 576                 return -ENOMEM;
 577
 578         if (len > op_len)
 579                 len = op_len;
 580
 581         if (map_perm & LDC_MAP_R)
 582                 memcpy(req_buf, buf, len);
 583
 584         spin_lock_irqsave(&port->vio.lock, flags);
 585
 586         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 587
 588         /* XXX If we want to use this code generically we have to
 589          * XXX handle TX ring exhaustion etc.
 590          */
 591         desc = vio_dring_cur(dr);
 592
 593         err = ldc_map_single(port->vio.lp, req_buf, op_len,
 594                              desc->cookies, port->ring_cookies,
 595                              map_perm);
 596         if (err < 0) {
 597                 spin_unlock_irqrestore(&port->vio.lock, flags);
 598                 kfree(req_buf);
 599                 return err;
 600         }
 601
 602         init_completion(&comp.com);
 603         comp.waiting_for = WAITING_FOR_GEN_CMD;
 604         port->vio.cmp = &comp;
 605
 606         desc->hdr.ack = VIO_ACK_ENABLE;
 607         desc->req_id = port->req_id;
 608         desc->operation = op;
 609         desc->slice = 0;
 610         desc->status = ~0;
 611         desc->offset = 0;
 612         desc->size = op_len;
 613         desc->ncookies = err;
 614
 615         /* This has to be a non-SMP write barrier because we are writing
 616          * to memory which is shared with the peer LDOM.
 617          */
 618         wmb();
 619         desc->hdr.state = VIO_DESC_READY;
 620
 621         err = __vdc_tx_trigger(port);
 622         if (err >= 0) {
 623                 port->req_id++;
 624                 dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
 625                 spin_unlock_irqrestore(&port->vio.lock, flags);
 626
 627                 wait_for_completion(&comp.com);
 628                 err = comp.err;
 629         } else {
 630                 port->vio.cmp = NULL;
 631                 spin_unlock_irqrestore(&port->vio.lock, flags);
 632         }
 633
 634         if (map_perm & LDC_MAP_W)
 635                 memcpy(buf, req_buf, len);
 636
 637         kfree(req_buf);
 638
 639         return err;
 640 }
 641
 642 static int vdc_alloc_tx_ring(struct vdc_port *port)
 643 {
 644         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 645         unsigned long len, entry_size;
 646         int ncookies;
 647         void *dring;
 648
 649         entry_size = sizeof(struct vio_disk_desc) +
 650                 (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
 651         len = (VDC_TX_RING_SIZE * entry_size);
 652
 653         ncookies = VIO_MAX_RING_COOKIES;
 654         dring = ldc_alloc_exp_dring(port->vio.lp, len,
 655                                     dr->cookies, &ncookies,
 656                                     (LDC_MAP_SHADOW |
 657                                      LDC_MAP_DIRECT |
 658                                      LDC_MAP_RW));
 659         if (IS_ERR(dring))
 660                 return PTR_ERR(dring);
 661
 662         dr->base = dring;
 663         dr->entry_size = entry_size;
 664         dr->num_entries = VDC_TX_RING_SIZE;
 665         dr->prod = dr->cons = 0;
 666         dr->pending = VDC_TX_RING_SIZE;
 667         dr->ncookies = ncookies;
 668
 669         return 0;
 670 }
 671
 672 static void vdc_free_tx_ring(struct vdc_port *port)
 673 {
 674         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 675
 676         if (dr->base) {
 677                 ldc_free_exp_dring(port->vio.lp, dr->base,
 678                                    (dr->entry_size * dr->num_entries),
 679                                    dr->cookies, dr->ncookies);
 680                 dr->base = NULL;
 681                 dr->entry_size = 0;
 682                 dr->num_entries = 0;
 683                 dr->pending = 0;
 684                 dr->ncookies = 0;
 685         }
 686 }
 687
 688 static int probe_disk(struct vdc_port *port)
 689 {
 690         struct vio_completion comp;
 691         struct request_queue *q;
 692         struct gendisk *g;
 693         int err;
 694
 695         init_completion(&comp.com);
 696         comp.err = 0;
 697         comp.waiting_for = WAITING_FOR_LINK_UP;
 698         port->vio.cmp = &comp;
 699
 700         vio_port_up(&port->vio);
 701
 702         wait_for_completion(&comp.com);
 703         if (comp.err)
 704                 return comp.err;
 705
 706         err = generic_request(port, VD_OP_GET_VTOC,
 707                               &port->label, sizeof(port->label));
 708         if (err < 0) {
 709                 printk(KERN_ERR PFX "VD_OP_GET_VTOC returns error %d\n", err);
 710                 return err;
 711         }
 712
 713         if (vdc_version_supported(port, 1, 1)) {
 714                 /* vdisk_size should be set during the handshake, if it wasn't
 715                  * then the underlying disk is reserved by another system
 716                  */
 717                 if (port->vdisk_size == -1)
 718                         return -ENODEV;
 719         } else {
 720                 struct vio_disk_geom geom;
 721
 722                 err = generic_request(port, VD_OP_GET_DISKGEOM,
 723                                       &geom, sizeof(geom));
 724                 if (err < 0) {
 725                         printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
 726                                "error %d\n", err);
 727                         return err;
 728                 }
 729                 port->vdisk_size = ((u64)geom.num_cyl *
 730                                     (u64)geom.num_hd *
 731                                     (u64)geom.num_sec);
 732         }
 733
 734         q = blk_init_queue(do_vdc_request, &port->vio.lock);
 735         if (!q) {
 736                 printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
 737                        port->vio.name);
 738                 return -ENOMEM;
 739         }
 740         g = alloc_disk(1 << PARTITION_SHIFT);
 741         if (!g) {
 742                 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
 743                        port->vio.name);
 744                 blk_cleanup_queue(q);
 745                 return -ENOMEM;
 746         }
 747
 748         port->disk = g;
 749
 750         blk_queue_max_segments(q, port->ring_cookies);
 751         blk_queue_max_hw_sectors(q, port->max_xfer_size);
 752         g->major = vdc_major;
 753         g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
 754         strcpy(g->disk_name, port->disk_name);
 755
 756         g->fops = &vdc_fops;
 757         g->queue = q;
 758         g->private_data = port;
 759         g->driverfs_dev = &port->vio.vdev->dev;
 760
 761         set_capacity(g, port->vdisk_size);
 762
 763         if (vdc_version_supported(port, 1, 1)) {
 764                 switch (port->vdisk_mtype) {
 765                 case VD_MEDIA_TYPE_CD:
 766                         pr_info(PFX "Virtual CDROM %s\n", port->disk_name);
 767                         g->flags |= GENHD_FL_CD;
 768                         g->flags |= GENHD_FL_REMOVABLE;
 769                         set_disk_ro(g, 1);
 770                         break;
 771
 772                 case VD_MEDIA_TYPE_DVD:
 773                         pr_info(PFX "Virtual DVD %s\n", port->disk_name);
 774                         g->flags |= GENHD_FL_CD;
 775                         g->flags |= GENHD_FL_REMOVABLE;
 776                         set_disk_ro(g, 1);
 777                         break;
 778
 779                 case VD_MEDIA_TYPE_FIXED:
 780                         pr_info(PFX "Virtual Hard disk %s\n", port->disk_name);
 781                         break;
 782                 }
 783         }
 784
 785         pr_info(PFX "%s: %u sectors (%u MB) protocol %d.%d\n",
 786                g->disk_name,
 787                port->vdisk_size, (port->vdisk_size >> (20 - 9)),
 788                port->vio.ver.major, port->vio.ver.minor);
 789
 790         add_disk(g);
 791
 792         return 0;
 793 }
 794
 795 static struct ldc_channel_config vdc_ldc_cfg = {
 796         .event          = vdc_event,
 797         .mtu            = 64,
 798         .mode           = LDC_MODE_UNRELIABLE,
 799 };
 800
 801 static struct vio_driver_ops vdc_vio_ops = {
 802         .send_attr              = vdc_send_attr,
 803         .handle_attr            = vdc_handle_attr,
 804         .handshake_complete     = vdc_handshake_complete,
 805 };
 806
 807 static void print_version(void)
 808 {
 809         static int version_printed;
 810
 811         if (version_printed++ == 0)
 812                 printk(KERN_INFO "%s", version);
 813 }
 814
 815 static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 816 {
 817         struct mdesc_handle *hp;
 818         struct vdc_port *port;
 819         int err;
 820
 821         print_version();
 822
 823         hp = mdesc_grab();
 824
 825         err = -ENODEV;
 826         if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
 827                 printk(KERN_ERR PFX "Port id [%llu] too large.\n",
 828                        vdev->dev_no);
 829                 goto err_out_release_mdesc;
 830         }
 831
 832         port = kzalloc(sizeof(*port), GFP_KERNEL);
 833         err = -ENOMEM;
 834         if (!port) {
 835                 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
 836                 goto err_out_release_mdesc;
 837         }
 838
 839         if (vdev->dev_no >= 26)
 840                 snprintf(port->disk_name, sizeof(port->disk_name),
 841                          VDCBLK_NAME "%c%c",
 842                          'a' + ((int)vdev->dev_no / 26) - 1,
 843                          'a' + ((int)vdev->dev_no % 26));
 844         else
 845                 snprintf(port->disk_name, sizeof(port->disk_name),
 846                          VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
 847         port->vdisk_size = -1;
 848
 849         err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
 850                               vdc_versions, ARRAY_SIZE(vdc_versions),
 851                               &vdc_vio_ops, port->disk_name);
 852         if (err)
 853                 goto err_out_free_port;
 854
 855         port->vdisk_block_size = 512;
 856         port->max_xfer_size = ((128 * 1024) / port->vdisk_block_size);
 857         port->ring_cookies = ((port->max_xfer_size *
 858                                port->vdisk_block_size) / PAGE_SIZE) + 2;
 859
 860         err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
 861         if (err)
 862                 goto err_out_free_port;
 863
 864         err = vdc_alloc_tx_ring(port);
 865         if (err)
 866                 goto err_out_free_ldc;
 867
 868         err = probe_disk(port);
 869         if (err)
 870                 goto err_out_free_tx_ring;
 871
 872         dev_set_drvdata(&vdev->dev, port);
 873
 874         mdesc_release(hp);
 875
 876         return 0;
 877
 878 err_out_free_tx_ring:
 879         vdc_free_tx_ring(port);
 880
 881 err_out_free_ldc:
 882         vio_ldc_free(&port->vio);
 883
 884 err_out_free_port:
 885         kfree(port);
 886
 887 err_out_release_mdesc:
 888         mdesc_release(hp);
 889         return err;
 890 }
 891
 892 static int vdc_port_remove(struct vio_dev *vdev)
 893 {
 894         struct vdc_port *port = dev_get_drvdata(&vdev->dev);
 895
 896         if (port) {
 897                 del_timer_sync(&port->vio.timer);
 898
 899                 vdc_free_tx_ring(port);
 900                 vio_ldc_free(&port->vio);
 901
 902                 dev_set_drvdata(&vdev->dev, NULL);
 903
 904                 kfree(port);
 905         }
 906         return 0;
 907 }
 908
 909 static const struct vio_device_id vdc_port_match[] = {
 910         {
 911                 .type = "vdc-port",
 912         },
 913         {},
 914 };
 915 MODULE_DEVICE_TABLE(vio, vdc_port_match);
 916
 917 static struct vio_driver vdc_port_driver = {
 918         .id_table       = vdc_port_match,
 919         .probe          = vdc_port_probe,
 920         .remove         = vdc_port_remove,
 921         .name           = "vdc_port",
 922 };
 923
 924 static int __init vdc_init(void)
 925 {
 926         int err;
 927
 928         err = register_blkdev(0, VDCBLK_NAME);
 929         if (err < 0)
 930                 goto out_err;
 931
 932         vdc_major = err;
 933
 934         err = vio_register_driver(&vdc_port_driver);
 935         if (err)
 936                 goto out_unregister_blkdev;
 937
 938         return 0;
 939
 940 out_unregister_blkdev:
 941         unregister_blkdev(vdc_major, VDCBLK_NAME);
 942         vdc_major = 0;
 943
 944 out_err:
 945         return err;
 946 }
 947
 948 static void __exit vdc_exit(void)
 949 {
 950         vio_unregister_driver(&vdc_port_driver);
 951         unregister_blkdev(vdc_major, VDCBLK_NAME);
 952 }
 953
 954 module_init(vdc_init);
 955 module_exit(vdc_exit);