linux/drivers/block/sunvdc.c
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   1/* sunvdc.c: Sun LDOM Virtual Disk Client.
   2 *
   3 * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
   4 */
   5
   6#include <linux/module.h>
   7#include <linux/kernel.h>
   8#include <linux/types.h>
   9#include <linux/blkdev.h>
  10#include <linux/hdreg.h>
  11#include <linux/genhd.h>
  12#include <linux/slab.h>
  13#include <linux/spinlock.h>
  14#include <linux/completion.h>
  15#include <linux/delay.h>
  16#include <linux/init.h>
  17#include <linux/list.h>
  18#include <linux/scatterlist.h>
  19
  20#include <asm/vio.h>
  21#include <asm/ldc.h>
  22
  23#define DRV_MODULE_NAME         "sunvdc"
  24#define PFX DRV_MODULE_NAME     ": "
  25#define DRV_MODULE_VERSION      "1.0"
  26#define DRV_MODULE_RELDATE      "June 25, 2007"
  27
  28static char version[] __devinitdata =
  29        DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
  30MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
  31MODULE_DESCRIPTION("Sun LDOM virtual disk client driver");
  32MODULE_LICENSE("GPL");
  33MODULE_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
  42struct vdc_req_entry {
  43        struct request          *req;
  44};
  45
  46struct 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
  75static 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 */
  81static struct vio_version vdc_versions[] = {
  82        { .major = 1, .minor = 0 },
  83};
  84
  85#define VDCBLK_NAME     "vdisk"
  86static int vdc_major;
  87#define PARTITION_SHIFT 3
  88
  89static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr)
  90{
  91        return vio_dring_avail(dr, VDC_TX_RING_SIZE);
  92}
  93
  94static 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
 106static struct block_device_operations vdc_fops = {
 107        .owner          = THIS_MODULE,
 108        .getgeo         = vdc_getgeo,
 109};
 110
 111static 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
 122static void vdc_handshake_complete(struct vio_driver_state *vio)
 123{
 124        vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
 125}
 126
 127static 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
 140static int vdc_send_attr(struct vio_driver_state *vio)
 141{
 142        struct vdc_port *port = to_vdc_port(vio);
 143        struct vio_disk_attr_info pkt;
 144
 145        memset(&pkt, 0, sizeof(pkt));
 146
 147        pkt.tag.type = VIO_TYPE_CTRL;
 148        pkt.tag.stype = VIO_SUBTYPE_INFO;
 149        pkt.tag.stype_env = VIO_ATTR_INFO;
 150        pkt.tag.sid = vio_send_sid(vio);
 151
 152        pkt.xfer_mode = VIO_DRING_MODE;
 153        pkt.vdisk_block_size = port->vdisk_block_size;
 154        pkt.max_xfer_size = port->max_xfer_size;
 155
 156        viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%lu]\n",
 157               pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size);
 158
 159        return vio_ldc_send(&port->vio, &pkt, sizeof(pkt));
 160}
 161
 162static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
 163{
 164        struct vdc_port *port = to_vdc_port(vio);
 165        struct vio_disk_attr_info *pkt = arg;
 166
 167        viodbg(HS, "GOT ATTR stype[0x%x] ops[%lx] disk_size[%lu] disk_type[%x] "
 168               "xfer_mode[0x%x] blksz[%u] max_xfer[%lu]\n",
 169               pkt->tag.stype, pkt->operations,
 170               pkt->vdisk_size, pkt->vdisk_type,
 171               pkt->xfer_mode, pkt->vdisk_block_size,
 172               pkt->max_xfer_size);
 173
 174        if (pkt->tag.stype == VIO_SUBTYPE_ACK) {
 175                switch (pkt->vdisk_type) {
 176                case VD_DISK_TYPE_DISK:
 177                case VD_DISK_TYPE_SLICE:
 178                        break;
 179
 180                default:
 181                        printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n",
 182                               vio->name, pkt->vdisk_type);
 183                        return -ECONNRESET;
 184                }
 185
 186                if (pkt->vdisk_block_size > port->vdisk_block_size) {
 187                        printk(KERN_ERR PFX "%s: BLOCK size increased "
 188                               "%u --> %u\n",
 189                               vio->name,
 190                               port->vdisk_block_size, pkt->vdisk_block_size);
 191                        return -ECONNRESET;
 192                }
 193
 194                port->operations = pkt->operations;
 195                port->vdisk_size = pkt->vdisk_size;
 196                port->vdisk_type = pkt->vdisk_type;
 197                if (pkt->max_xfer_size < port->max_xfer_size)
 198                        port->max_xfer_size = pkt->max_xfer_size;
 199                port->vdisk_block_size = pkt->vdisk_block_size;
 200                return 0;
 201        } else {
 202                printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name);
 203
 204                return -ECONNRESET;
 205        }
 206}
 207
 208static 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
 215static void vdc_end_request(struct request *req, int error, int num_sectors)
 216{
 217        __blk_end_request(req, error, num_sectors << 9);
 218}
 219
 220static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
 221                        unsigned int index)
 222{
 223        struct vio_disk_desc *desc = vio_dring_entry(dr, index);
 224        struct vdc_req_entry *rqe = &port->rq_arr[index];
 225        struct request *req;
 226
 227        if (unlikely(desc->hdr.state != VIO_DESC_DONE))
 228                return;
 229
 230        ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
 231        desc->hdr.state = VIO_DESC_FREE;
 232        dr->cons = (index + 1) & (VDC_TX_RING_SIZE - 1);
 233
 234        req = rqe->req;
 235        if (req == NULL) {
 236                vdc_end_special(port, desc);
 237                return;
 238        }
 239
 240        rqe->req = NULL;
 241
 242        vdc_end_request(req, (desc->status ? -EIO : 0), desc->size >> 9);
 243
 244        if (blk_queue_stopped(port->disk->queue))
 245                blk_start_queue(port->disk->queue);
 246}
 247
 248static int vdc_ack(struct vdc_port *port, void *msgbuf)
 249{
 250        struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 251        struct vio_dring_data *pkt = msgbuf;
 252
 253        if (unlikely(pkt->dring_ident != dr->ident ||
 254                     pkt->start_idx != pkt->end_idx ||
 255                     pkt->start_idx >= VDC_TX_RING_SIZE))
 256                return 0;
 257
 258        vdc_end_one(port, dr, pkt->start_idx);
 259
 260        return 0;
 261}
 262
 263static int vdc_nack(struct vdc_port *port, void *msgbuf)
 264{
 265        /* XXX Implement me XXX */
 266        return 0;
 267}
 268
 269static void vdc_event(void *arg, int event)
 270{
 271        struct vdc_port *port = arg;
 272        struct vio_driver_state *vio = &port->vio;
 273        unsigned long flags;
 274        int err;
 275
 276        spin_lock_irqsave(&vio->lock, flags);
 277
 278        if (unlikely(event == LDC_EVENT_RESET ||
 279                     event == LDC_EVENT_UP)) {
 280                vio_link_state_change(vio, event);
 281                spin_unlock_irqrestore(&vio->lock, flags);
 282                return;
 283        }
 284
 285        if (unlikely(event != LDC_EVENT_DATA_READY)) {
 286                printk(KERN_WARNING PFX "Unexpected LDC event %d\n", event);
 287                spin_unlock_irqrestore(&vio->lock, flags);
 288                return;
 289        }
 290
 291        err = 0;
 292        while (1) {
 293                union {
 294                        struct vio_msg_tag tag;
 295                        u64 raw[8];
 296                } msgbuf;
 297
 298                err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
 299                if (unlikely(err < 0)) {
 300                        if (err == -ECONNRESET)
 301                                vio_conn_reset(vio);
 302                        break;
 303                }
 304                if (err == 0)
 305                        break;
 306                viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
 307                       msgbuf.tag.type,
 308                       msgbuf.tag.stype,
 309                       msgbuf.tag.stype_env,
 310                       msgbuf.tag.sid);
 311                err = vio_validate_sid(vio, &msgbuf.tag);
 312                if (err < 0)
 313                        break;
 314
 315                if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
 316                        if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
 317                                err = vdc_ack(port, &msgbuf);
 318                        else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
 319                                err = vdc_nack(port, &msgbuf);
 320                        else
 321                                err = vdc_handle_unknown(port, &msgbuf);
 322                } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
 323                        err = vio_control_pkt_engine(vio, &msgbuf);
 324                } else {
 325                        err = vdc_handle_unknown(port, &msgbuf);
 326                }
 327                if (err < 0)
 328                        break;
 329        }
 330        if (err < 0)
 331                vdc_finish(&port->vio, err, WAITING_FOR_ANY);
 332        spin_unlock_irqrestore(&vio->lock, flags);
 333}
 334
 335static int __vdc_tx_trigger(struct vdc_port *port)
 336{
 337        struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 338        struct vio_dring_data hdr = {
 339                .tag = {
 340                        .type           = VIO_TYPE_DATA,
 341                        .stype          = VIO_SUBTYPE_INFO,
 342                        .stype_env      = VIO_DRING_DATA,
 343                        .sid            = vio_send_sid(&port->vio),
 344                },
 345                .dring_ident            = dr->ident,
 346                .start_idx              = dr->prod,
 347                .end_idx                = dr->prod,
 348        };
 349        int err, delay;
 350
 351        hdr.seq = dr->snd_nxt;
 352        delay = 1;
 353        do {
 354                err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
 355                if (err > 0) {
 356                        dr->snd_nxt++;
 357                        break;
 358                }
 359                udelay(delay);
 360                if ((delay <<= 1) > 128)
 361                        delay = 128;
 362        } while (err == -EAGAIN);
 363
 364        return err;
 365}
 366
 367static int __send_request(struct request *req)
 368{
 369        struct vdc_port *port = req->rq_disk->private_data;
 370        struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 371        struct scatterlist sg[port->ring_cookies];
 372        struct vdc_req_entry *rqe;
 373        struct vio_disk_desc *desc;
 374        unsigned int map_perm;
 375        int nsg, err, i;
 376        u64 len;
 377        u8 op;
 378
 379        map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 380
 381        if (rq_data_dir(req) == READ) {
 382                map_perm |= LDC_MAP_W;
 383                op = VD_OP_BREAD;
 384        } else {
 385                map_perm |= LDC_MAP_R;
 386                op = VD_OP_BWRITE;
 387        }
 388
 389        sg_init_table(sg, port->ring_cookies);
 390        nsg = blk_rq_map_sg(req->q, req, sg);
 391
 392        len = 0;
 393        for (i = 0; i < nsg; i++)
 394                len += sg[i].length;
 395
 396        if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
 397                blk_stop_queue(port->disk->queue);
 398                err = -ENOMEM;
 399                goto out;
 400        }
 401
 402        desc = vio_dring_cur(dr);
 403
 404        err = ldc_map_sg(port->vio.lp, sg, nsg,
 405                         desc->cookies, port->ring_cookies,
 406                         map_perm);
 407        if (err < 0) {
 408                printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
 409                return err;
 410        }
 411
 412        rqe = &port->rq_arr[dr->prod];
 413        rqe->req = req;
 414
 415        desc->hdr.ack = VIO_ACK_ENABLE;
 416        desc->req_id = port->req_id;
 417        desc->operation = op;
 418        if (port->vdisk_type == VD_DISK_TYPE_DISK) {
 419                desc->slice = 0xff;
 420        } else {
 421                desc->slice = 0;
 422        }
 423        desc->status = ~0;
 424        desc->offset = (req->sector << 9) / port->vdisk_block_size;
 425        desc->size = len;
 426        desc->ncookies = err;
 427
 428        /* This has to be a non-SMP write barrier because we are writing
 429         * to memory which is shared with the peer LDOM.
 430         */
 431        wmb();
 432        desc->hdr.state = VIO_DESC_READY;
 433
 434        err = __vdc_tx_trigger(port);
 435        if (err < 0) {
 436                printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
 437        } else {
 438                port->req_id++;
 439                dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
 440        }
 441out:
 442
 443        return err;
 444}
 445
 446static void do_vdc_request(struct request_queue *q)
 447{
 448        while (1) {
 449                struct request *req = elv_next_request(q);
 450
 451                if (!req)
 452                        break;
 453
 454                blkdev_dequeue_request(req);
 455                if (__send_request(req) < 0)
 456                        vdc_end_request(req, -EIO, req->hard_nr_sectors);
 457        }
 458}
 459
 460static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
 461{
 462        struct vio_dring_state *dr;
 463        struct vio_completion comp;
 464        struct vio_disk_desc *desc;
 465        unsigned int map_perm;
 466        unsigned long flags;
 467        int op_len, err;
 468        void *req_buf;
 469
 470        if (!(((u64)1 << ((u64)op - 1)) & port->operations))
 471                return -EOPNOTSUPP;
 472
 473        switch (op) {
 474        case VD_OP_BREAD:
 475        case VD_OP_BWRITE:
 476        default:
 477                return -EINVAL;
 478
 479        case VD_OP_FLUSH:
 480                op_len = 0;
 481                map_perm = 0;
 482                break;
 483
 484        case VD_OP_GET_WCE:
 485                op_len = sizeof(u32);
 486                map_perm = LDC_MAP_W;
 487                break;
 488
 489        case VD_OP_SET_WCE:
 490                op_len = sizeof(u32);
 491                map_perm = LDC_MAP_R;
 492                break;
 493
 494        case VD_OP_GET_VTOC:
 495                op_len = sizeof(struct vio_disk_vtoc);
 496                map_perm = LDC_MAP_W;
 497                break;
 498
 499        case VD_OP_SET_VTOC:
 500                op_len = sizeof(struct vio_disk_vtoc);
 501                map_perm = LDC_MAP_R;
 502                break;
 503
 504        case VD_OP_GET_DISKGEOM:
 505                op_len = sizeof(struct vio_disk_geom);
 506                map_perm = LDC_MAP_W;
 507                break;
 508
 509        case VD_OP_SET_DISKGEOM:
 510                op_len = sizeof(struct vio_disk_geom);
 511                map_perm = LDC_MAP_R;
 512                break;
 513
 514        case VD_OP_SCSICMD:
 515                op_len = 16;
 516                map_perm = LDC_MAP_RW;
 517                break;
 518
 519        case VD_OP_GET_DEVID:
 520                op_len = sizeof(struct vio_disk_devid);
 521                map_perm = LDC_MAP_W;
 522                break;
 523
 524        case VD_OP_GET_EFI:
 525        case VD_OP_SET_EFI:
 526                return -EOPNOTSUPP;
 527                break;
 528        };
 529
 530        map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 531
 532        op_len = (op_len + 7) & ~7;
 533        req_buf = kzalloc(op_len, GFP_KERNEL);
 534        if (!req_buf)
 535                return -ENOMEM;
 536
 537        if (len > op_len)
 538                len = op_len;
 539
 540        if (map_perm & LDC_MAP_R)
 541                memcpy(req_buf, buf, len);
 542
 543        spin_lock_irqsave(&port->vio.lock, flags);
 544
 545        dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 546
 547        /* XXX If we want to use this code generically we have to
 548         * XXX handle TX ring exhaustion etc.
 549         */
 550        desc = vio_dring_cur(dr);
 551
 552        err = ldc_map_single(port->vio.lp, req_buf, op_len,
 553                             desc->cookies, port->ring_cookies,
 554                             map_perm);
 555        if (err < 0) {
 556                spin_unlock_irqrestore(&port->vio.lock, flags);
 557                kfree(req_buf);
 558                return err;
 559        }
 560
 561        init_completion(&comp.com);
 562        comp.waiting_for = WAITING_FOR_GEN_CMD;
 563        port->vio.cmp = &comp;
 564
 565        desc->hdr.ack = VIO_ACK_ENABLE;
 566        desc->req_id = port->req_id;
 567        desc->operation = op;
 568        desc->slice = 0;
 569        desc->status = ~0;
 570        desc->offset = 0;
 571        desc->size = op_len;
 572        desc->ncookies = err;
 573
 574        /* This has to be a non-SMP write barrier because we are writing
 575         * to memory which is shared with the peer LDOM.
 576         */
 577        wmb();
 578        desc->hdr.state = VIO_DESC_READY;
 579
 580        err = __vdc_tx_trigger(port);
 581        if (err >= 0) {
 582                port->req_id++;
 583                dr->prod = (dr->prod + 1) & (VDC_TX_RING_SIZE - 1);
 584                spin_unlock_irqrestore(&port->vio.lock, flags);
 585
 586                wait_for_completion(&comp.com);
 587                err = comp.err;
 588        } else {
 589                port->vio.cmp = NULL;
 590                spin_unlock_irqrestore(&port->vio.lock, flags);
 591        }
 592
 593        if (map_perm & LDC_MAP_W)
 594                memcpy(buf, req_buf, len);
 595
 596        kfree(req_buf);
 597
 598        return err;
 599}
 600
 601static int __devinit vdc_alloc_tx_ring(struct vdc_port *port)
 602{
 603        struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 604        unsigned long len, entry_size;
 605        int ncookies;
 606        void *dring;
 607
 608        entry_size = sizeof(struct vio_disk_desc) +
 609                (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
 610        len = (VDC_TX_RING_SIZE * entry_size);
 611
 612        ncookies = VIO_MAX_RING_COOKIES;
 613        dring = ldc_alloc_exp_dring(port->vio.lp, len,
 614                                    dr->cookies, &ncookies,
 615                                    (LDC_MAP_SHADOW |
 616                                     LDC_MAP_DIRECT |
 617                                     LDC_MAP_RW));
 618        if (IS_ERR(dring))
 619                return PTR_ERR(dring);
 620
 621        dr->base = dring;
 622        dr->entry_size = entry_size;
 623        dr->num_entries = VDC_TX_RING_SIZE;
 624        dr->prod = dr->cons = 0;
 625        dr->pending = VDC_TX_RING_SIZE;
 626        dr->ncookies = ncookies;
 627
 628        return 0;
 629}
 630
 631static void vdc_free_tx_ring(struct vdc_port *port)
 632{
 633        struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 634
 635        if (dr->base) {
 636                ldc_free_exp_dring(port->vio.lp, dr->base,
 637                                   (dr->entry_size * dr->num_entries),
 638                                   dr->cookies, dr->ncookies);
 639                dr->base = NULL;
 640                dr->entry_size = 0;
 641                dr->num_entries = 0;
 642                dr->pending = 0;
 643                dr->ncookies = 0;
 644        }
 645}
 646
 647static int probe_disk(struct vdc_port *port)
 648{
 649        struct vio_completion comp;
 650        struct request_queue *q;
 651        struct gendisk *g;
 652        int err;
 653
 654        init_completion(&comp.com);
 655        comp.err = 0;
 656        comp.waiting_for = WAITING_FOR_LINK_UP;
 657        port->vio.cmp = &comp;
 658
 659        vio_port_up(&port->vio);
 660
 661        wait_for_completion(&comp.com);
 662        if (comp.err)
 663                return comp.err;
 664
 665        err = generic_request(port, VD_OP_GET_VTOC,
 666                              &port->label, sizeof(port->label));
 667        if (err < 0) {
 668                printk(KERN_ERR PFX "VD_OP_GET_VTOC returns error %d\n", err);
 669                return err;
 670        }
 671
 672        err = generic_request(port, VD_OP_GET_DISKGEOM,
 673                              &port->geom, sizeof(port->geom));
 674        if (err < 0) {
 675                printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
 676                       "error %d\n", err);
 677                return err;
 678        }
 679
 680        port->vdisk_size = ((u64)port->geom.num_cyl *
 681                            (u64)port->geom.num_hd *
 682                            (u64)port->geom.num_sec);
 683
 684        q = blk_init_queue(do_vdc_request, &port->vio.lock);
 685        if (!q) {
 686                printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
 687                       port->vio.name);
 688                return -ENOMEM;
 689        }
 690        g = alloc_disk(1 << PARTITION_SHIFT);
 691        if (!g) {
 692                printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
 693                       port->vio.name);
 694                blk_cleanup_queue(q);
 695                return -ENOMEM;
 696        }
 697
 698        port->disk = g;
 699
 700        blk_queue_max_hw_segments(q, port->ring_cookies);
 701        blk_queue_max_phys_segments(q, port->ring_cookies);
 702        blk_queue_max_sectors(q, port->max_xfer_size);
 703        g->major = vdc_major;
 704        g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
 705        strcpy(g->disk_name, port->disk_name);
 706
 707        g->fops = &vdc_fops;
 708        g->queue = q;
 709        g->private_data = port;
 710        g->driverfs_dev = &port->vio.vdev->dev;
 711
 712        set_capacity(g, port->vdisk_size);
 713
 714        printk(KERN_INFO PFX "%s: %u sectors (%u MB)\n",
 715               g->disk_name,
 716               port->vdisk_size, (port->vdisk_size >> (20 - 9)));
 717
 718        add_disk(g);
 719
 720        return 0;
 721}
 722
 723static struct ldc_channel_config vdc_ldc_cfg = {
 724        .event          = vdc_event,
 725        .mtu            = 64,
 726        .mode           = LDC_MODE_UNRELIABLE,
 727};
 728
 729static struct vio_driver_ops vdc_vio_ops = {
 730        .send_attr              = vdc_send_attr,
 731        .handle_attr            = vdc_handle_attr,
 732        .handshake_complete     = vdc_handshake_complete,
 733};
 734
 735static void __devinit print_version(void)
 736{
 737        static int version_printed;
 738
 739        if (version_printed++ == 0)
 740                printk(KERN_INFO "%s", version);
 741}
 742
 743static int __devinit vdc_port_probe(struct vio_dev *vdev,
 744                                    const struct vio_device_id *id)
 745{
 746        struct mdesc_handle *hp;
 747        struct vdc_port *port;
 748        int err;
 749
 750        print_version();
 751
 752        hp = mdesc_grab();
 753
 754        err = -ENODEV;
 755        if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
 756                printk(KERN_ERR PFX "Port id [%lu] too large.\n",
 757                       vdev->dev_no);
 758                goto err_out_release_mdesc;
 759        }
 760
 761        port = kzalloc(sizeof(*port), GFP_KERNEL);
 762        err = -ENOMEM;
 763        if (!port) {
 764                printk(KERN_ERR PFX "Cannot allocate vdc_port.\n");
 765                goto err_out_release_mdesc;
 766        }
 767
 768        if (vdev->dev_no >= 26)
 769                snprintf(port->disk_name, sizeof(port->disk_name),
 770                         VDCBLK_NAME "%c%c",
 771                         'a' + ((int)vdev->dev_no / 26) - 1,
 772                         'a' + ((int)vdev->dev_no % 26));
 773        else
 774                snprintf(port->disk_name, sizeof(port->disk_name),
 775                         VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
 776
 777        err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
 778                              vdc_versions, ARRAY_SIZE(vdc_versions),
 779                              &vdc_vio_ops, port->disk_name);
 780        if (err)
 781                goto err_out_free_port;
 782
 783        port->vdisk_block_size = 512;
 784        port->max_xfer_size = ((128 * 1024) / port->vdisk_block_size);
 785        port->ring_cookies = ((port->max_xfer_size *
 786                               port->vdisk_block_size) / PAGE_SIZE) + 2;
 787
 788        err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
 789        if (err)
 790                goto err_out_free_port;
 791
 792        err = vdc_alloc_tx_ring(port);
 793        if (err)
 794                goto err_out_free_ldc;
 795
 796        err = probe_disk(port);
 797        if (err)
 798                goto err_out_free_tx_ring;
 799
 800        dev_set_drvdata(&vdev->dev, port);
 801
 802        mdesc_release(hp);
 803
 804        return 0;
 805
 806err_out_free_tx_ring:
 807        vdc_free_tx_ring(port);
 808
 809err_out_free_ldc:
 810        vio_ldc_free(&port->vio);
 811
 812err_out_free_port:
 813        kfree(port);
 814
 815err_out_release_mdesc:
 816        mdesc_release(hp);
 817        return err;
 818}
 819
 820static int vdc_port_remove(struct vio_dev *vdev)
 821{
 822        struct vdc_port *port = dev_get_drvdata(&vdev->dev);
 823
 824        if (port) {
 825                del_timer_sync(&port->vio.timer);
 826
 827                vdc_free_tx_ring(port);
 828                vio_ldc_free(&port->vio);
 829
 830                dev_set_drvdata(&vdev->dev, NULL);
 831
 832                kfree(port);
 833        }
 834        return 0;
 835}
 836
 837static struct vio_device_id vdc_port_match[] = {
 838        {
 839                .type = "vdc-port",
 840        },
 841        {},
 842};
 843MODULE_DEVICE_TABLE(vio, vdc_port_match);
 844
 845static struct vio_driver vdc_port_driver = {
 846        .id_table       = vdc_port_match,
 847        .probe          = vdc_port_probe,
 848        .remove         = vdc_port_remove,
 849        .driver         = {
 850                .name   = "vdc_port",
 851                .owner  = THIS_MODULE,
 852        }
 853};
 854
 855static int __init vdc_init(void)
 856{
 857        int err;
 858
 859        err = register_blkdev(0, VDCBLK_NAME);
 860        if (err < 0)
 861                goto out_err;
 862
 863        vdc_major = err;
 864
 865        err = vio_register_driver(&vdc_port_driver);
 866        if (err)
 867                goto out_unregister_blkdev;
 868
 869        return 0;
 870
 871out_unregister_blkdev:
 872        unregister_blkdev(vdc_major, VDCBLK_NAME);
 873        vdc_major = 0;
 874
 875out_err:
 876        return err;
 877}
 878
 879static void __exit vdc_exit(void)
 880{
 881        vio_unregister_driver(&vdc_port_driver);
 882        unregister_blkdev(vdc_major, VDCBLK_NAME);
 883}
 884
 885module_init(vdc_init);
 886module_exit(vdc_exit);
 887