drivers/block/sunvdc.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* sunvdc.c: Sun LDOM Virtual Disk Client.
   3  *
   4  * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/kernel.h>
   9 #include <linux/types.h>
  10 #include <linux/blk-mq.h>
  11 #include <linux/hdreg.h>
  12 #include <linux/genhd.h>
  13 #include <linux/cdrom.h>
  14 #include <linux/slab.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/completion.h>
  17 #include <linux/delay.h>
  18 #include <linux/init.h>
  19 #include <linux/list.h>
  20 #include <linux/scatterlist.h>
  21
  22 #include <asm/vio.h>
  23 #include <asm/ldc.h>
  24
  25 #define DRV_MODULE_NAME         "sunvdc"
  26 #define PFX DRV_MODULE_NAME     ": "
  27 #define DRV_MODULE_VERSION      "1.2"
  28 #define DRV_MODULE_RELDATE      "November 24, 2014"
  29
  30 static char version[] =
  31         DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n";
  32 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
  33 MODULE_DESCRIPTION("Sun LDOM virtual disk client driver");
  34 MODULE_LICENSE("GPL");
  35 MODULE_VERSION(DRV_MODULE_VERSION);
  36
  37 #define VDC_TX_RING_SIZE        512
  38 #define VDC_DEFAULT_BLK_SIZE    512
  39
  40 #define MAX_XFER_BLKS           (128 * 1024)
  41 #define MAX_XFER_SIZE           (MAX_XFER_BLKS / VDC_DEFAULT_BLK_SIZE)
  42 #define MAX_RING_COOKIES        ((MAX_XFER_BLKS / PAGE_SIZE) + 2)
  43
  44 #define WAITING_FOR_LINK_UP     0x01
  45 #define WAITING_FOR_TX_SPACE    0x02
  46 #define WAITING_FOR_GEN_CMD     0x04
  47 #define WAITING_FOR_ANY         -1
  48
  49 #define VDC_MAX_RETRIES 10
  50
  51 static struct workqueue_struct *sunvdc_wq;
  52
  53 struct vdc_req_entry {
  54         struct request          *req;
  55 };
  56
  57 struct vdc_port {
  58         struct vio_driver_state vio;
  59
  60         struct gendisk          *disk;
  61
  62         struct vdc_completion   *cmp;
  63
  64         u64                     req_id;
  65         u64                     seq;
  66         struct vdc_req_entry    rq_arr[VDC_TX_RING_SIZE];
  67
  68         unsigned long           ring_cookies;
  69
  70         u64                     max_xfer_size;
  71         u32                     vdisk_block_size;
  72         u32                     drain;
  73
  74         u64                     ldc_timeout;
  75         struct delayed_work     ldc_reset_timer_work;
  76         struct work_struct      ldc_reset_work;
  77
  78         /* The server fills these in for us in the disk attribute
  79          * ACK packet.
  80          */
  81         u64                     operations;
  82         u32                     vdisk_size;
  83         u8                      vdisk_type;
  84         u8                      vdisk_mtype;
  85         u32                     vdisk_phys_blksz;
  86
  87         struct blk_mq_tag_set   tag_set;
  88
  89         char                    disk_name[32];
  90 };
  91
  92 static void vdc_ldc_reset(struct vdc_port *port);
  93 static void vdc_ldc_reset_work(struct work_struct *work);
  94 static void vdc_ldc_reset_timer_work(struct work_struct *work);
  95
  96 static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio)
  97 {
  98         return container_of(vio, struct vdc_port, vio);
  99 }
 100
 101 /* Ordered from largest major to lowest */
 102 static struct vio_version vdc_versions[] = {
 103         { .major = 1, .minor = 2 },
 104         { .major = 1, .minor = 1 },
 105         { .major = 1, .minor = 0 },
 106 };
 107
 108 static inline int vdc_version_supported(struct vdc_port *port,
 109                                         u16 major, u16 minor)
 110 {
 111         return port->vio.ver.major == major && port->vio.ver.minor >= minor;
 112 }
 113
 114 #define VDCBLK_NAME     "vdisk"
 115 static int vdc_major;
 116 #define PARTITION_SHIFT 3
 117
 118 static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr)
 119 {
 120         return vio_dring_avail(dr, VDC_TX_RING_SIZE);
 121 }
 122
 123 static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 124 {
 125         struct gendisk *disk = bdev->bd_disk;
 126         sector_t nsect = get_capacity(disk);
 127         sector_t cylinders = nsect;
 128
 129         geo->heads = 0xff;
 130         geo->sectors = 0x3f;
 131         sector_div(cylinders, geo->heads * geo->sectors);
 132         geo->cylinders = cylinders;
 133         if ((sector_t)(geo->cylinders + 1) * geo->heads * geo->sectors < nsect)
 134                 geo->cylinders = 0xffff;
 135
 136         return 0;
 137 }
 138
 139 /* Add ioctl/CDROM_GET_CAPABILITY to support cdrom_id in udev
 140  * when vdisk_mtype is VD_MEDIA_TYPE_CD or VD_MEDIA_TYPE_DVD.
 141  * Needed to be able to install inside an ldom from an iso image.
 142  */
 143 static int vdc_ioctl(struct block_device *bdev, fmode_t mode,
 144                      unsigned command, unsigned long argument)
 145 {
 146         struct vdc_port *port = bdev->bd_disk->private_data;
 147         int i;
 148
 149         switch (command) {
 150         case CDROMMULTISESSION:
 151                 pr_debug(PFX "Multisession CDs not supported\n");
 152                 for (i = 0; i < sizeof(struct cdrom_multisession); i++)
 153                         if (put_user(0, (char __user *)(argument + i)))
 154                                 return -EFAULT;
 155                 return 0;
 156
 157         case CDROM_GET_CAPABILITY:
 158                 if (!vdc_version_supported(port, 1, 1))
 159                         return -EINVAL;
 160                 switch (port->vdisk_mtype) {
 161                 case VD_MEDIA_TYPE_CD:
 162                 case VD_MEDIA_TYPE_DVD:
 163                         return 0;
 164                 default:
 165                         return -EINVAL;
 166                 }
 167         default:
 168                 pr_debug(PFX "ioctl %08x not supported\n", command);
 169                 return -EINVAL;
 170         }
 171 }
 172
 173 static const struct block_device_operations vdc_fops = {
 174         .owner          = THIS_MODULE,
 175         .getgeo         = vdc_getgeo,
 176         .ioctl          = vdc_ioctl,
 177         .compat_ioctl   = blkdev_compat_ptr_ioctl,
 178 };
 179
 180 static void vdc_blk_queue_start(struct vdc_port *port)
 181 {
 182         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 183
 184         /* restart blk queue when ring is half emptied. also called after
 185          * handshake completes, so check for initial handshake before we've
 186          * allocated a disk.
 187          */
 188         if (port->disk && vdc_tx_dring_avail(dr) * 100 / VDC_TX_RING_SIZE >= 50)
 189                 blk_mq_start_stopped_hw_queues(port->disk->queue, true);
 190 }
 191
 192 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for)
 193 {
 194         if (vio->cmp &&
 195             (waiting_for == -1 ||
 196              vio->cmp->waiting_for == waiting_for)) {
 197                 vio->cmp->err = err;
 198                 complete(&vio->cmp->com);
 199                 vio->cmp = NULL;
 200         }
 201 }
 202
 203 static void vdc_handshake_complete(struct vio_driver_state *vio)
 204 {
 205         struct vdc_port *port = to_vdc_port(vio);
 206
 207         cancel_delayed_work(&port->ldc_reset_timer_work);
 208         vdc_finish(vio, 0, WAITING_FOR_LINK_UP);
 209         vdc_blk_queue_start(port);
 210 }
 211
 212 static int vdc_handle_unknown(struct vdc_port *port, void *arg)
 213 {
 214         struct vio_msg_tag *pkt = arg;
 215
 216         printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n",
 217                pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
 218         printk(KERN_ERR PFX "Resetting connection.\n");
 219
 220         ldc_disconnect(port->vio.lp);
 221
 222         return -ECONNRESET;
 223 }
 224
 225 static int vdc_send_attr(struct vio_driver_state *vio)
 226 {
 227         struct vdc_port *port = to_vdc_port(vio);
 228         struct vio_disk_attr_info pkt;
 229
 230         memset(&pkt, 0, sizeof(pkt));
 231
 232         pkt.tag.type = VIO_TYPE_CTRL;
 233         pkt.tag.stype = VIO_SUBTYPE_INFO;
 234         pkt.tag.stype_env = VIO_ATTR_INFO;
 235         pkt.tag.sid = vio_send_sid(vio);
 236
 237         pkt.xfer_mode = VIO_DRING_MODE;
 238         pkt.vdisk_block_size = port->vdisk_block_size;
 239         pkt.max_xfer_size = port->max_xfer_size;
 240
 241         viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
 242                pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size);
 243
 244         return vio_ldc_send(&port->vio, &pkt, sizeof(pkt));
 245 }
 246
 247 static int vdc_handle_attr(struct vio_driver_state *vio, void *arg)
 248 {
 249         struct vdc_port *port = to_vdc_port(vio);
 250         struct vio_disk_attr_info *pkt = arg;
 251
 252         viodbg(HS, "GOT ATTR stype[0x%x] ops[%llx] disk_size[%llu] disk_type[%x] "
 253                "mtype[0x%x] xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n",
 254                pkt->tag.stype, pkt->operations,
 255                pkt->vdisk_size, pkt->vdisk_type, pkt->vdisk_mtype,
 256                pkt->xfer_mode, pkt->vdisk_block_size,
 257                pkt->max_xfer_size);
 258
 259         if (pkt->tag.stype == VIO_SUBTYPE_ACK) {
 260                 switch (pkt->vdisk_type) {
 261                 case VD_DISK_TYPE_DISK:
 262                 case VD_DISK_TYPE_SLICE:
 263                         break;
 264
 265                 default:
 266                         printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n",
 267                                vio->name, pkt->vdisk_type);
 268                         return -ECONNRESET;
 269                 }
 270
 271                 if (pkt->vdisk_block_size > port->vdisk_block_size) {
 272                         printk(KERN_ERR PFX "%s: BLOCK size increased "
 273                                "%u --> %u\n",
 274                                vio->name,
 275                                port->vdisk_block_size, pkt->vdisk_block_size);
 276                         return -ECONNRESET;
 277                 }
 278
 279                 port->operations = pkt->operations;
 280                 port->vdisk_type = pkt->vdisk_type;
 281                 if (vdc_version_supported(port, 1, 1)) {
 282                         port->vdisk_size = pkt->vdisk_size;
 283                         port->vdisk_mtype = pkt->vdisk_mtype;
 284                 }
 285                 if (pkt->max_xfer_size < port->max_xfer_size)
 286                         port->max_xfer_size = pkt->max_xfer_size;
 287                 port->vdisk_block_size = pkt->vdisk_block_size;
 288
 289                 port->vdisk_phys_blksz = VDC_DEFAULT_BLK_SIZE;
 290                 if (vdc_version_supported(port, 1, 2))
 291                         port->vdisk_phys_blksz = pkt->phys_block_size;
 292
 293                 return 0;
 294         } else {
 295                 printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name);
 296
 297                 return -ECONNRESET;
 298         }
 299 }
 300
 301 static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc)
 302 {
 303         int err = desc->status;
 304
 305         vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD);
 306 }
 307
 308 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr,
 309                         unsigned int index)
 310 {
 311         struct vio_disk_desc *desc = vio_dring_entry(dr, index);
 312         struct vdc_req_entry *rqe = &port->rq_arr[index];
 313         struct request *req;
 314
 315         if (unlikely(desc->hdr.state != VIO_DESC_DONE))
 316                 return;
 317
 318         ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
 319         desc->hdr.state = VIO_DESC_FREE;
 320         dr->cons = vio_dring_next(dr, index);
 321
 322         req = rqe->req;
 323         if (req == NULL) {
 324                 vdc_end_special(port, desc);
 325                 return;
 326         }
 327
 328         rqe->req = NULL;
 329
 330         blk_mq_end_request(req, desc->status ? BLK_STS_IOERR : 0);
 331
 332         vdc_blk_queue_start(port);
 333 }
 334
 335 static int vdc_ack(struct vdc_port *port, void *msgbuf)
 336 {
 337         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 338         struct vio_dring_data *pkt = msgbuf;
 339
 340         if (unlikely(pkt->dring_ident != dr->ident ||
 341                      pkt->start_idx != pkt->end_idx ||
 342                      pkt->start_idx >= VDC_TX_RING_SIZE))
 343                 return 0;
 344
 345         vdc_end_one(port, dr, pkt->start_idx);
 346
 347         return 0;
 348 }
 349
 350 static int vdc_nack(struct vdc_port *port, void *msgbuf)
 351 {
 352         /* XXX Implement me XXX */
 353         return 0;
 354 }
 355
 356 static void vdc_event(void *arg, int event)
 357 {
 358         struct vdc_port *port = arg;
 359         struct vio_driver_state *vio = &port->vio;
 360         unsigned long flags;
 361         int err;
 362
 363         spin_lock_irqsave(&vio->lock, flags);
 364
 365         if (unlikely(event == LDC_EVENT_RESET)) {
 366                 vio_link_state_change(vio, event);
 367                 queue_work(sunvdc_wq, &port->ldc_reset_work);
 368                 goto out;
 369         }
 370
 371         if (unlikely(event == LDC_EVENT_UP)) {
 372                 vio_link_state_change(vio, event);
 373                 goto out;
 374         }
 375
 376         if (unlikely(event != LDC_EVENT_DATA_READY)) {
 377                 pr_warn(PFX "Unexpected LDC event %d\n", event);
 378                 goto out;
 379         }
 380
 381         err = 0;
 382         while (1) {
 383                 union {
 384                         struct vio_msg_tag tag;
 385                         u64 raw[8];
 386                 } msgbuf;
 387
 388                 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf));
 389                 if (unlikely(err < 0)) {
 390                         if (err == -ECONNRESET)
 391                                 vio_conn_reset(vio);
 392                         break;
 393                 }
 394                 if (err == 0)
 395                         break;
 396                 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n",
 397                        msgbuf.tag.type,
 398                        msgbuf.tag.stype,
 399                        msgbuf.tag.stype_env,
 400                        msgbuf.tag.sid);
 401                 err = vio_validate_sid(vio, &msgbuf.tag);
 402                 if (err < 0)
 403                         break;
 404
 405                 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) {
 406                         if (msgbuf.tag.stype == VIO_SUBTYPE_ACK)
 407                                 err = vdc_ack(port, &msgbuf);
 408                         else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK)
 409                                 err = vdc_nack(port, &msgbuf);
 410                         else
 411                                 err = vdc_handle_unknown(port, &msgbuf);
 412                 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) {
 413                         err = vio_control_pkt_engine(vio, &msgbuf);
 414                 } else {
 415                         err = vdc_handle_unknown(port, &msgbuf);
 416                 }
 417                 if (err < 0)
 418                         break;
 419         }
 420         if (err < 0)
 421                 vdc_finish(&port->vio, err, WAITING_FOR_ANY);
 422 out:
 423         spin_unlock_irqrestore(&vio->lock, flags);
 424 }
 425
 426 static int __vdc_tx_trigger(struct vdc_port *port)
 427 {
 428         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 429         struct vio_dring_data hdr = {
 430                 .tag = {
 431                         .type           = VIO_TYPE_DATA,
 432                         .stype          = VIO_SUBTYPE_INFO,
 433                         .stype_env      = VIO_DRING_DATA,
 434                         .sid            = vio_send_sid(&port->vio),
 435                 },
 436                 .dring_ident            = dr->ident,
 437                 .start_idx              = dr->prod,
 438                 .end_idx                = dr->prod,
 439         };
 440         int err, delay;
 441         int retries = 0;
 442
 443         hdr.seq = dr->snd_nxt;
 444         delay = 1;
 445         do {
 446                 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr));
 447                 if (err > 0) {
 448                         dr->snd_nxt++;
 449                         break;
 450                 }
 451                 udelay(delay);
 452                 if ((delay <<= 1) > 128)
 453                         delay = 128;
 454                 if (retries++ > VDC_MAX_RETRIES)
 455                         break;
 456         } while (err == -EAGAIN);
 457
 458         if (err == -ENOTCONN)
 459                 vdc_ldc_reset(port);
 460         return err;
 461 }
 462
 463 static int __send_request(struct request *req)
 464 {
 465         struct vdc_port *port = req->q->disk->private_data;
 466         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 467         struct scatterlist sg[MAX_RING_COOKIES];
 468         struct vdc_req_entry *rqe;
 469         struct vio_disk_desc *desc;
 470         unsigned int map_perm;
 471         int nsg, err, i;
 472         u64 len;
 473         u8 op;
 474
 475         if (WARN_ON(port->ring_cookies > MAX_RING_COOKIES))
 476                 return -EINVAL;
 477
 478         map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 479
 480         if (rq_data_dir(req) == READ) {
 481                 map_perm |= LDC_MAP_W;
 482                 op = VD_OP_BREAD;
 483         } else {
 484                 map_perm |= LDC_MAP_R;
 485                 op = VD_OP_BWRITE;
 486         }
 487
 488         sg_init_table(sg, port->ring_cookies);
 489         nsg = blk_rq_map_sg(req->q, req, sg);
 490
 491         len = 0;
 492         for (i = 0; i < nsg; i++)
 493                 len += sg[i].length;
 494
 495         desc = vio_dring_cur(dr);
 496
 497         err = ldc_map_sg(port->vio.lp, sg, nsg,
 498                          desc->cookies, port->ring_cookies,
 499                          map_perm);
 500         if (err < 0) {
 501                 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err);
 502                 return err;
 503         }
 504
 505         rqe = &port->rq_arr[dr->prod];
 506         rqe->req = req;
 507
 508         desc->hdr.ack = VIO_ACK_ENABLE;
 509         desc->req_id = port->req_id;
 510         desc->operation = op;
 511         if (port->vdisk_type == VD_DISK_TYPE_DISK) {
 512                 desc->slice = 0xff;
 513         } else {
 514                 desc->slice = 0;
 515         }
 516         desc->status = ~0;
 517         desc->offset = (blk_rq_pos(req) << 9) / port->vdisk_block_size;
 518         desc->size = len;
 519         desc->ncookies = err;
 520
 521         /* This has to be a non-SMP write barrier because we are writing
 522          * to memory which is shared with the peer LDOM.
 523          */
 524         wmb();
 525         desc->hdr.state = VIO_DESC_READY;
 526
 527         err = __vdc_tx_trigger(port);
 528         if (err < 0) {
 529                 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err);
 530         } else {
 531                 port->req_id++;
 532                 dr->prod = vio_dring_next(dr, dr->prod);
 533         }
 534
 535         return err;
 536 }
 537
 538 static blk_status_t vdc_queue_rq(struct blk_mq_hw_ctx *hctx,
 539                                  const struct blk_mq_queue_data *bd)
 540 {
 541         struct vdc_port *port = hctx->queue->queuedata;
 542         struct vio_dring_state *dr;
 543         unsigned long flags;
 544
 545         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 546
 547         blk_mq_start_request(bd->rq);
 548
 549         spin_lock_irqsave(&port->vio.lock, flags);
 550
 551         /*
 552          * Doing drain, just end the request in error
 553          */
 554         if (unlikely(port->drain)) {
 555                 spin_unlock_irqrestore(&port->vio.lock, flags);
 556                 return BLK_STS_IOERR;
 557         }
 558
 559         if (unlikely(vdc_tx_dring_avail(dr) < 1)) {
 560                 spin_unlock_irqrestore(&port->vio.lock, flags);
 561                 blk_mq_stop_hw_queue(hctx);
 562                 return BLK_STS_DEV_RESOURCE;
 563         }
 564
 565         if (__send_request(bd->rq) < 0) {
 566                 spin_unlock_irqrestore(&port->vio.lock, flags);
 567                 return BLK_STS_IOERR;
 568         }
 569
 570         spin_unlock_irqrestore(&port->vio.lock, flags);
 571         return BLK_STS_OK;
 572 }
 573
 574 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len)
 575 {
 576         struct vio_dring_state *dr;
 577         struct vio_completion comp;
 578         struct vio_disk_desc *desc;
 579         unsigned int map_perm;
 580         unsigned long flags;
 581         int op_len, err;
 582         void *req_buf;
 583
 584         if (!(((u64)1 << (u64)op) & port->operations))
 585                 return -EOPNOTSUPP;
 586
 587         switch (op) {
 588         case VD_OP_BREAD:
 589         case VD_OP_BWRITE:
 590         default:
 591                 return -EINVAL;
 592
 593         case VD_OP_FLUSH:
 594                 op_len = 0;
 595                 map_perm = 0;
 596                 break;
 597
 598         case VD_OP_GET_WCE:
 599                 op_len = sizeof(u32);
 600                 map_perm = LDC_MAP_W;
 601                 break;
 602
 603         case VD_OP_SET_WCE:
 604                 op_len = sizeof(u32);
 605                 map_perm = LDC_MAP_R;
 606                 break;
 607
 608         case VD_OP_GET_VTOC:
 609                 op_len = sizeof(struct vio_disk_vtoc);
 610                 map_perm = LDC_MAP_W;
 611                 break;
 612
 613         case VD_OP_SET_VTOC:
 614                 op_len = sizeof(struct vio_disk_vtoc);
 615                 map_perm = LDC_MAP_R;
 616                 break;
 617
 618         case VD_OP_GET_DISKGEOM:
 619                 op_len = sizeof(struct vio_disk_geom);
 620                 map_perm = LDC_MAP_W;
 621                 break;
 622
 623         case VD_OP_SET_DISKGEOM:
 624                 op_len = sizeof(struct vio_disk_geom);
 625                 map_perm = LDC_MAP_R;
 626                 break;
 627
 628         case VD_OP_SCSICMD:
 629                 op_len = 16;
 630                 map_perm = LDC_MAP_RW;
 631                 break;
 632
 633         case VD_OP_GET_DEVID:
 634                 op_len = sizeof(struct vio_disk_devid);
 635                 map_perm = LDC_MAP_W;
 636                 break;
 637
 638         case VD_OP_GET_EFI:
 639         case VD_OP_SET_EFI:
 640                 return -EOPNOTSUPP;
 641         }
 642
 643         map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO;
 644
 645         op_len = (op_len + 7) & ~7;
 646         req_buf = kzalloc(op_len, GFP_KERNEL);
 647         if (!req_buf)
 648                 return -ENOMEM;
 649
 650         if (len > op_len)
 651                 len = op_len;
 652
 653         if (map_perm & LDC_MAP_R)
 654                 memcpy(req_buf, buf, len);
 655
 656         spin_lock_irqsave(&port->vio.lock, flags);
 657
 658         dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 659
 660         /* XXX If we want to use this code generically we have to
 661          * XXX handle TX ring exhaustion etc.
 662          */
 663         desc = vio_dring_cur(dr);
 664
 665         err = ldc_map_single(port->vio.lp, req_buf, op_len,
 666                              desc->cookies, port->ring_cookies,
 667                              map_perm);
 668         if (err < 0) {
 669                 spin_unlock_irqrestore(&port->vio.lock, flags);
 670                 kfree(req_buf);
 671                 return err;
 672         }
 673
 674         init_completion(&comp.com);
 675         comp.waiting_for = WAITING_FOR_GEN_CMD;
 676         port->vio.cmp = &comp;
 677
 678         desc->hdr.ack = VIO_ACK_ENABLE;
 679         desc->req_id = port->req_id;
 680         desc->operation = op;
 681         desc->slice = 0;
 682         desc->status = ~0;
 683         desc->offset = 0;
 684         desc->size = op_len;
 685         desc->ncookies = err;
 686
 687         /* This has to be a non-SMP write barrier because we are writing
 688          * to memory which is shared with the peer LDOM.
 689          */
 690         wmb();
 691         desc->hdr.state = VIO_DESC_READY;
 692
 693         err = __vdc_tx_trigger(port);
 694         if (err >= 0) {
 695                 port->req_id++;
 696                 dr->prod = vio_dring_next(dr, dr->prod);
 697                 spin_unlock_irqrestore(&port->vio.lock, flags);
 698
 699                 wait_for_completion(&comp.com);
 700                 err = comp.err;
 701         } else {
 702                 port->vio.cmp = NULL;
 703                 spin_unlock_irqrestore(&port->vio.lock, flags);
 704         }
 705
 706         if (map_perm & LDC_MAP_W)
 707                 memcpy(buf, req_buf, len);
 708
 709         kfree(req_buf);
 710
 711         return err;
 712 }
 713
 714 static int vdc_alloc_tx_ring(struct vdc_port *port)
 715 {
 716         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 717         unsigned long len, entry_size;
 718         int ncookies;
 719         void *dring;
 720
 721         entry_size = sizeof(struct vio_disk_desc) +
 722                 (sizeof(struct ldc_trans_cookie) * port->ring_cookies);
 723         len = (VDC_TX_RING_SIZE * entry_size);
 724
 725         ncookies = VIO_MAX_RING_COOKIES;
 726         dring = ldc_alloc_exp_dring(port->vio.lp, len,
 727                                     dr->cookies, &ncookies,
 728                                     (LDC_MAP_SHADOW |
 729                                      LDC_MAP_DIRECT |
 730                                      LDC_MAP_RW));
 731         if (IS_ERR(dring))
 732                 return PTR_ERR(dring);
 733
 734         dr->base = dring;
 735         dr->entry_size = entry_size;
 736         dr->num_entries = VDC_TX_RING_SIZE;
 737         dr->prod = dr->cons = 0;
 738         dr->pending = VDC_TX_RING_SIZE;
 739         dr->ncookies = ncookies;
 740
 741         return 0;
 742 }
 743
 744 static void vdc_free_tx_ring(struct vdc_port *port)
 745 {
 746         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
 747
 748         if (dr->base) {
 749                 ldc_free_exp_dring(port->vio.lp, dr->base,
 750                                    (dr->entry_size * dr->num_entries),
 751                                    dr->cookies, dr->ncookies);
 752                 dr->base = NULL;
 753                 dr->entry_size = 0;
 754                 dr->num_entries = 0;
 755                 dr->pending = 0;
 756                 dr->ncookies = 0;
 757         }
 758 }
 759
 760 static int vdc_port_up(struct vdc_port *port)
 761 {
 762         struct vio_completion comp;
 763
 764         init_completion(&comp.com);
 765         comp.err = 0;
 766         comp.waiting_for = WAITING_FOR_LINK_UP;
 767         port->vio.cmp = &comp;
 768
 769         vio_port_up(&port->vio);
 770         wait_for_completion(&comp.com);
 771         return comp.err;
 772 }
 773
 774 static void vdc_port_down(struct vdc_port *port)
 775 {
 776         ldc_disconnect(port->vio.lp);
 777         ldc_unbind(port->vio.lp);
 778         vdc_free_tx_ring(port);
 779         vio_ldc_free(&port->vio);
 780 }
 781
 782 static const struct blk_mq_ops vdc_mq_ops = {
 783         .queue_rq       = vdc_queue_rq,
 784 };
 785
 786 static int probe_disk(struct vdc_port *port)
 787 {
 788         struct request_queue *q;
 789         struct gendisk *g;
 790         int err;
 791
 792         err = vdc_port_up(port);
 793         if (err)
 794                 return err;
 795
 796         /* Using version 1.2 means vdisk_phys_blksz should be set unless the
 797          * disk is reserved by another system.
 798          */
 799         if (vdc_version_supported(port, 1, 2) && !port->vdisk_phys_blksz)
 800                 return -ENODEV;
 801
 802         if (vdc_version_supported(port, 1, 1)) {
 803                 /* vdisk_size should be set during the handshake, if it wasn't
 804                  * then the underlying disk is reserved by another system
 805                  */
 806                 if (port->vdisk_size == -1)
 807                         return -ENODEV;
 808         } else {
 809                 struct vio_disk_geom geom;
 810
 811                 err = generic_request(port, VD_OP_GET_DISKGEOM,
 812                                       &geom, sizeof(geom));
 813                 if (err < 0) {
 814                         printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns "
 815                                "error %d\n", err);
 816                         return err;
 817                 }
 818                 port->vdisk_size = ((u64)geom.num_cyl *
 819                                     (u64)geom.num_hd *
 820                                     (u64)geom.num_sec);
 821         }
 822
 823         err = blk_mq_alloc_sq_tag_set(&port->tag_set, &vdc_mq_ops,
 824                         VDC_TX_RING_SIZE, BLK_MQ_F_SHOULD_MERGE);
 825         if (err)
 826                 return err;
 827
 828         g = blk_mq_alloc_disk(&port->tag_set, port);
 829         if (IS_ERR(g)) {
 830                 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
 831                        port->vio.name);
 832                 err = PTR_ERR(g);
 833                 goto out_free_tag;
 834         }
 835
 836         port->disk = g;
 837         q = g->queue;
 838
 839         /* Each segment in a request is up to an aligned page in size. */
 840         blk_queue_segment_boundary(q, PAGE_SIZE - 1);
 841         blk_queue_max_segment_size(q, PAGE_SIZE);
 842
 843         blk_queue_max_segments(q, port->ring_cookies);
 844         blk_queue_max_hw_sectors(q, port->max_xfer_size);
 845         g->major = vdc_major;
 846         g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
 847         g->minors = 1 << PARTITION_SHIFT;
 848         strcpy(g->disk_name, port->disk_name);
 849
 850         g->fops = &vdc_fops;
 851         g->queue = q;
 852         g->private_data = port;
 853
 854         set_capacity(g, port->vdisk_size);
 855
 856         if (vdc_version_supported(port, 1, 1)) {
 857                 switch (port->vdisk_mtype) {
 858                 case VD_MEDIA_TYPE_CD:
 859                         pr_info(PFX "Virtual CDROM %s\n", port->disk_name);
 860                         g->flags |= GENHD_FL_REMOVABLE;
 861                         set_disk_ro(g, 1);
 862                         break;
 863
 864                 case VD_MEDIA_TYPE_DVD:
 865                         pr_info(PFX "Virtual DVD %s\n", port->disk_name);
 866                         g->flags |= GENHD_FL_REMOVABLE;
 867                         set_disk_ro(g, 1);
 868                         break;
 869
 870                 case VD_MEDIA_TYPE_FIXED:
 871                         pr_info(PFX "Virtual Hard disk %s\n", port->disk_name);
 872                         break;
 873                 }
 874         }
 875
 876         blk_queue_physical_block_size(q, port->vdisk_phys_blksz);
 877
 878         pr_info(PFX "%s: %u sectors (%u MB) protocol %d.%d\n",
 879                g->disk_name,
 880                port->vdisk_size, (port->vdisk_size >> (20 - 9)),
 881                port->vio.ver.major, port->vio.ver.minor);
 882
 883         err = device_add_disk(&port->vio.vdev->dev, g, NULL);
 884         if (err)
 885                 goto out_cleanup_disk;
 886
 887         return 0;
 888
 889 out_cleanup_disk:
 890         blk_cleanup_disk(g);
 891 out_free_tag:
 892         blk_mq_free_tag_set(&port->tag_set);
 893         return err;
 894 }
 895
 896 static struct ldc_channel_config vdc_ldc_cfg = {
 897         .event          = vdc_event,
 898         .mtu            = 64,
 899         .mode           = LDC_MODE_UNRELIABLE,
 900 };
 901
 902 static struct vio_driver_ops vdc_vio_ops = {
 903         .send_attr              = vdc_send_attr,
 904         .handle_attr            = vdc_handle_attr,
 905         .handshake_complete     = vdc_handshake_complete,
 906 };
 907
 908 static void print_version(void)
 909 {
 910         static int version_printed;
 911
 912         if (version_printed++ == 0)
 913                 printk(KERN_INFO "%s", version);
 914 }
 915
 916 struct vdc_check_port_data {
 917         int     dev_no;
 918         char    *type;
 919 };
 920
 921 static int vdc_device_probed(struct device *dev, void *arg)
 922 {
 923         struct vio_dev *vdev = to_vio_dev(dev);
 924         struct vdc_check_port_data *port_data;
 925
 926         port_data = (struct vdc_check_port_data *)arg;
 927
 928         if ((vdev->dev_no == port_data->dev_no) &&
 929             (!(strcmp((char *)&vdev->type, port_data->type))) &&
 930                 dev_get_drvdata(dev)) {
 931                 /* This device has already been configured
 932                  * by vdc_port_probe()
 933                  */
 934                 return 1;
 935         } else {
 936                 return 0;
 937         }
 938 }
 939
 940 /* Determine whether the VIO device is part of an mpgroup
 941  * by locating all the virtual-device-port nodes associated
 942  * with the parent virtual-device node for the VIO device
 943  * and checking whether any of these nodes are vdc-ports
 944  * which have already been configured.
 945  *
 946  * Returns true if this device is part of an mpgroup and has
 947  * already been probed.
 948  */
 949 static bool vdc_port_mpgroup_check(struct vio_dev *vdev)
 950 {
 951         struct vdc_check_port_data port_data;
 952         struct device *dev;
 953
 954         port_data.dev_no = vdev->dev_no;
 955         port_data.type = (char *)&vdev->type;
 956
 957         dev = device_find_child(vdev->dev.parent, &port_data,
 958                                 vdc_device_probed);
 959
 960         if (dev)
 961                 return true;
 962
 963         return false;
 964 }
 965
 966 static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 967 {
 968         struct mdesc_handle *hp;
 969         struct vdc_port *port;
 970         int err;
 971         const u64 *ldc_timeout;
 972
 973         print_version();
 974
 975         hp = mdesc_grab();
 976
 977         err = -ENODEV;
 978         if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) {
 979                 printk(KERN_ERR PFX "Port id [%llu] too large.\n",
 980                        vdev->dev_no);
 981                 goto err_out_release_mdesc;
 982         }
 983
 984         /* Check if this device is part of an mpgroup */
 985         if (vdc_port_mpgroup_check(vdev)) {
 986                 printk(KERN_WARNING
 987                         "VIO: Ignoring extra vdisk port %s",
 988                         dev_name(&vdev->dev));
 989                 goto err_out_release_mdesc;
 990         }
 991
 992         port = kzalloc(sizeof(*port), GFP_KERNEL);
 993         if (!port) {
 994                 err = -ENOMEM;
 995                 goto err_out_release_mdesc;
 996         }
 997
 998         if (vdev->dev_no >= 26)
 999                 snprintf(port->disk_name, sizeof(port->disk_name),
1000                          VDCBLK_NAME "%c%c",
1001                          'a' + ((int)vdev->dev_no / 26) - 1,
1002                          'a' + ((int)vdev->dev_no % 26));
1003         else
1004                 snprintf(port->disk_name, sizeof(port->disk_name),
1005                          VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26));
1006         port->vdisk_size = -1;
1007
1008         /* Actual wall time may be double due to do_generic_file_read() doing
1009          * a readahead I/O first, and once that fails it will try to read a
1010          * single page.
1011          */
1012         ldc_timeout = mdesc_get_property(hp, vdev->mp, "vdc-timeout", NULL);
1013         port->ldc_timeout = ldc_timeout ? *ldc_timeout : 0;
1014         INIT_DELAYED_WORK(&port->ldc_reset_timer_work, vdc_ldc_reset_timer_work);
1015         INIT_WORK(&port->ldc_reset_work, vdc_ldc_reset_work);
1016
1017         err = vio_driver_init(&port->vio, vdev, VDEV_DISK,
1018                               vdc_versions, ARRAY_SIZE(vdc_versions),
1019                               &vdc_vio_ops, port->disk_name);
1020         if (err)
1021                 goto err_out_free_port;
1022
1023         port->vdisk_block_size = VDC_DEFAULT_BLK_SIZE;
1024         port->max_xfer_size = MAX_XFER_SIZE;
1025         port->ring_cookies = MAX_RING_COOKIES;
1026
1027         err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
1028         if (err)
1029                 goto err_out_free_port;
1030
1031         err = vdc_alloc_tx_ring(port);
1032         if (err)
1033                 goto err_out_free_ldc;
1034
1035         err = probe_disk(port);
1036         if (err)
1037                 goto err_out_free_tx_ring;
1038
1039         /* Note that the device driver_data is used to determine
1040          * whether the port has been probed.
1041          */
1042         dev_set_drvdata(&vdev->dev, port);
1043
1044         mdesc_release(hp);
1045
1046         return 0;
1047
1048 err_out_free_tx_ring:
1049         vdc_free_tx_ring(port);
1050
1051 err_out_free_ldc:
1052         vio_ldc_free(&port->vio);
1053
1054 err_out_free_port:
1055         kfree(port);
1056
1057 err_out_release_mdesc:
1058         mdesc_release(hp);
1059         return err;
1060 }
1061
1062 static void vdc_port_remove(struct vio_dev *vdev)
1063 {
1064         struct vdc_port *port = dev_get_drvdata(&vdev->dev);
1065
1066         if (port) {
1067                 blk_mq_stop_hw_queues(port->disk->queue);
1068
1069                 flush_work(&port->ldc_reset_work);
1070                 cancel_delayed_work_sync(&port->ldc_reset_timer_work);
1071                 del_timer_sync(&port->vio.timer);
1072
1073                 del_gendisk(port->disk);
1074                 blk_cleanup_disk(port->disk);
1075                 blk_mq_free_tag_set(&port->tag_set);
1076
1077                 vdc_free_tx_ring(port);
1078                 vio_ldc_free(&port->vio);
1079
1080                 dev_set_drvdata(&vdev->dev, NULL);
1081
1082                 kfree(port);
1083         }
1084 }
1085
1086 static void vdc_requeue_inflight(struct vdc_port *port)
1087 {
1088         struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING];
1089         u32 idx;
1090
1091         for (idx = dr->cons; idx != dr->prod; idx = vio_dring_next(dr, idx)) {
1092                 struct vio_disk_desc *desc = vio_dring_entry(dr, idx);
1093                 struct vdc_req_entry *rqe = &port->rq_arr[idx];
1094                 struct request *req;
1095
1096                 ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies);
1097                 desc->hdr.state = VIO_DESC_FREE;
1098                 dr->cons = vio_dring_next(dr, idx);
1099
1100                 req = rqe->req;
1101                 if (req == NULL) {
1102                         vdc_end_special(port, desc);
1103                         continue;
1104                 }
1105
1106                 rqe->req = NULL;
1107                 blk_mq_requeue_request(req, false);
1108         }
1109 }
1110
1111 static void vdc_queue_drain(struct vdc_port *port)
1112 {
1113         struct request_queue *q = port->disk->queue;
1114
1115         /*
1116          * Mark the queue as draining, then freeze/quiesce to ensure
1117          * that all existing requests are seen in ->queue_rq() and killed
1118          */
1119         port->drain = 1;
1120         spin_unlock_irq(&port->vio.lock);
1121
1122         blk_mq_freeze_queue(q);
1123         blk_mq_quiesce_queue(q);
1124
1125         spin_lock_irq(&port->vio.lock);
1126         port->drain = 0;
1127         blk_mq_unquiesce_queue(q);
1128         blk_mq_unfreeze_queue(q);
1129 }
1130
1131 static void vdc_ldc_reset_timer_work(struct work_struct *work)
1132 {
1133         struct vdc_port *port;
1134         struct vio_driver_state *vio;
1135
1136         port = container_of(work, struct vdc_port, ldc_reset_timer_work.work);
1137         vio = &port->vio;
1138
1139         spin_lock_irq(&vio->lock);
1140         if (!(port->vio.hs_state & VIO_HS_COMPLETE)) {
1141                 pr_warn(PFX "%s ldc down %llu seconds, draining queue\n",
1142                         port->disk_name, port->ldc_timeout);
1143                 vdc_queue_drain(port);
1144                 vdc_blk_queue_start(port);
1145         }
1146         spin_unlock_irq(&vio->lock);
1147 }
1148
1149 static void vdc_ldc_reset_work(struct work_struct *work)
1150 {
1151         struct vdc_port *port;
1152         struct vio_driver_state *vio;
1153         unsigned long flags;
1154
1155         port = container_of(work, struct vdc_port, ldc_reset_work);
1156         vio = &port->vio;
1157
1158         spin_lock_irqsave(&vio->lock, flags);
1159         vdc_ldc_reset(port);
1160         spin_unlock_irqrestore(&vio->lock, flags);
1161 }
1162
1163 static void vdc_ldc_reset(struct vdc_port *port)
1164 {
1165         int err;
1166
1167         assert_spin_locked(&port->vio.lock);
1168
1169         pr_warn(PFX "%s ldc link reset\n", port->disk_name);
1170         blk_mq_stop_hw_queues(port->disk->queue);
1171         vdc_requeue_inflight(port);
1172         vdc_port_down(port);
1173
1174         err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port);
1175         if (err) {
1176                 pr_err(PFX "%s vio_ldc_alloc:%d\n", port->disk_name, err);
1177                 return;
1178         }
1179
1180         err = vdc_alloc_tx_ring(port);
1181         if (err) {
1182                 pr_err(PFX "%s vio_alloc_tx_ring:%d\n", port->disk_name, err);
1183                 goto err_free_ldc;
1184         }
1185
1186         if (port->ldc_timeout)
1187                 mod_delayed_work(system_wq, &port->ldc_reset_timer_work,
1188                           round_jiffies(jiffies + HZ * port->ldc_timeout));
1189         mod_timer(&port->vio.timer, round_jiffies(jiffies + HZ));
1190         return;
1191
1192 err_free_ldc:
1193         vio_ldc_free(&port->vio);
1194 }
1195
1196 static const struct vio_device_id vdc_port_match[] = {
1197         {
1198                 .type = "vdc-port",
1199         },
1200         {},
1201 };
1202 MODULE_DEVICE_TABLE(vio, vdc_port_match);
1203
1204 static struct vio_driver vdc_port_driver = {
1205         .id_table       = vdc_port_match,
1206         .probe          = vdc_port_probe,
1207         .remove         = vdc_port_remove,
1208         .name           = "vdc_port",
1209 };
1210
1211 static int __init vdc_init(void)
1212 {
1213         int err;
1214
1215         sunvdc_wq = alloc_workqueue("sunvdc", 0, 0);
1216         if (!sunvdc_wq)
1217                 return -ENOMEM;
1218
1219         err = register_blkdev(0, VDCBLK_NAME);
1220         if (err < 0)
1221                 goto out_free_wq;
1222
1223         vdc_major = err;
1224
1225         err = vio_register_driver(&vdc_port_driver);
1226         if (err)
1227                 goto out_unregister_blkdev;
1228
1229         return 0;
1230
1231 out_unregister_blkdev:
1232         unregister_blkdev(vdc_major, VDCBLK_NAME);
1233         vdc_major = 0;
1234
1235 out_free_wq:
1236         destroy_workqueue(sunvdc_wq);
1237         return err;
1238 }
1239
1240 static void __exit vdc_exit(void)
1241 {
1242         vio_unregister_driver(&vdc_port_driver);
1243         unregister_blkdev(vdc_major, VDCBLK_NAME);
1244         destroy_workqueue(sunvdc_wq);
1245 }
1246
1247 module_init(vdc_init);
1248 module_exit(vdc_exit);