drivers/char/viotape.c

   1 /* -*- linux-c -*-
   2  *  drivers/char/viotape.c
   3  *
   4  *  iSeries Virtual Tape
   5  *
   6  *  Authors: Dave Boutcher <boutcher@us.ibm.com>
   7  *           Ryan Arnold <ryanarn@us.ibm.com>
   8  *           Colin Devilbiss <devilbis@us.ibm.com>
   9  *           Stephen Rothwell <sfr@au1.ibm.com>
  10  *
  11  * (C) Copyright 2000-2004 IBM Corporation
  12  *
  13  * This program is free software;  you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License as
  15  * published by the Free Software Foundation; either version 2 of the
  16  * License, or (at your option) anyu later version.
  17  *
  18  * This program is distributed in the hope that it will be useful, but
  19  * WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21  * General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software Foundation,
  25  * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  26  *
  27  * This routine provides access to tape drives owned and managed by an OS/400
  28  * partition running on the same box as this Linux partition.
  29  *
  30  * All tape operations are performed by sending messages back and forth to
  31  * the OS/400 partition.  The format of the messages is defined in
  32  * iseries/vio.h
  33  */
  34 #include <linux/module.h>
  35 #include <linux/kernel.h>
  36 #include <linux/errno.h>
  37 #include <linux/init.h>
  38 #include <linux/wait.h>
  39 #include <linux/spinlock.h>
  40 #include <linux/mtio.h>
  41 #include <linux/device.h>
  42 #include <linux/dma-mapping.h>
  43 #include <linux/fs.h>
  44 #include <linux/cdev.h>
  45 #include <linux/major.h>
  46 #include <linux/completion.h>
  47 #include <linux/proc_fs.h>
  48 #include <linux/seq_file.h>
  49
  50 #include <asm/uaccess.h>
  51 #include <asm/ioctls.h>
  52
  53 #include <asm/vio.h>
  54 #include <asm/iseries/vio.h>
  55 #include <asm/iseries/hv_lp_event.h>
  56 #include <asm/iseries/hv_call_event.h>
  57 #include <asm/iseries/hv_lp_config.h>
  58
  59 #define VIOTAPE_VERSION         "1.2"
  60 #define VIOTAPE_MAXREQ          1
  61
  62 #define VIOTAPE_KERN_WARN       KERN_WARNING "viotape: "
  63 #define VIOTAPE_KERN_INFO       KERN_INFO "viotape: "
  64
  65 static int viotape_numdev;
  66
  67 /*
  68  * The minor number follows the conventions of the SCSI tape drives.  The
  69  * rewind and mode are encoded in the minor #.  We use this struct to break
  70  * them out
  71  */
  72 struct viot_devinfo_struct {
  73         int devno;
  74         int mode;
  75         int rewind;
  76 };
  77
  78 #define VIOTAPOP_RESET          0
  79 #define VIOTAPOP_FSF            1
  80 #define VIOTAPOP_BSF            2
  81 #define VIOTAPOP_FSR            3
  82 #define VIOTAPOP_BSR            4
  83 #define VIOTAPOP_WEOF           5
  84 #define VIOTAPOP_REW            6
  85 #define VIOTAPOP_NOP            7
  86 #define VIOTAPOP_EOM            8
  87 #define VIOTAPOP_ERASE          9
  88 #define VIOTAPOP_SETBLK        10
  89 #define VIOTAPOP_SETDENSITY    11
  90 #define VIOTAPOP_SETPOS        12
  91 #define VIOTAPOP_GETPOS        13
  92 #define VIOTAPOP_SETPART       14
  93 #define VIOTAPOP_UNLOAD        15
  94
  95 struct viotapelpevent {
  96         struct HvLpEvent event;
  97         u32 reserved;
  98         u16 version;
  99         u16 sub_type_result;
 100         u16 tape;
 101         u16 flags;
 102         u32 token;
 103         u64 len;
 104         union {
 105                 struct {
 106                         u32 tape_op;
 107                         u32 count;
 108                 } op;
 109                 struct {
 110                         u32 type;
 111                         u32 resid;
 112                         u32 dsreg;
 113                         u32 gstat;
 114                         u32 erreg;
 115                         u32 file_no;
 116                         u32 block_no;
 117                 } get_status;
 118                 struct {
 119                         u32 block_no;
 120                 } get_pos;
 121         } u;
 122 };
 123
 124 enum viotapesubtype {
 125         viotapeopen = 0x0001,
 126         viotapeclose = 0x0002,
 127         viotaperead = 0x0003,
 128         viotapewrite = 0x0004,
 129         viotapegetinfo = 0x0005,
 130         viotapeop = 0x0006,
 131         viotapegetpos = 0x0007,
 132         viotapesetpos = 0x0008,
 133         viotapegetstatus = 0x0009
 134 };
 135
 136 enum viotaperc {
 137         viotape_InvalidRange = 0x0601,
 138         viotape_InvalidToken = 0x0602,
 139         viotape_DMAError = 0x0603,
 140         viotape_UseError = 0x0604,
 141         viotape_ReleaseError = 0x0605,
 142         viotape_InvalidTape = 0x0606,
 143         viotape_InvalidOp = 0x0607,
 144         viotape_TapeErr = 0x0608,
 145
 146         viotape_AllocTimedOut = 0x0640,
 147         viotape_BOTEnc = 0x0641,
 148         viotape_BlankTape = 0x0642,
 149         viotape_BufferEmpty = 0x0643,
 150         viotape_CleanCartFound = 0x0644,
 151         viotape_CmdNotAllowed = 0x0645,
 152         viotape_CmdNotSupported = 0x0646,
 153         viotape_DataCheck = 0x0647,
 154         viotape_DecompressErr = 0x0648,
 155         viotape_DeviceTimeout = 0x0649,
 156         viotape_DeviceUnavail = 0x064a,
 157         viotape_DeviceBusy = 0x064b,
 158         viotape_EndOfMedia = 0x064c,
 159         viotape_EndOfTape = 0x064d,
 160         viotape_EquipCheck = 0x064e,
 161         viotape_InsufficientRs = 0x064f,
 162         viotape_InvalidLogBlk = 0x0650,
 163         viotape_LengthError = 0x0651,
 164         viotape_LibDoorOpen = 0x0652,
 165         viotape_LoadFailure = 0x0653,
 166         viotape_NotCapable = 0x0654,
 167         viotape_NotOperational = 0x0655,
 168         viotape_NotReady = 0x0656,
 169         viotape_OpCancelled = 0x0657,
 170         viotape_PhyLinkErr = 0x0658,
 171         viotape_RdyNotBOT = 0x0659,
 172         viotape_TapeMark = 0x065a,
 173         viotape_WriteProt = 0x065b
 174 };
 175
 176 static const struct vio_error_entry viotape_err_table[] = {
 177         { viotape_InvalidRange, EIO, "Internal error" },
 178         { viotape_InvalidToken, EIO, "Internal error" },
 179         { viotape_DMAError, EIO, "DMA error" },
 180         { viotape_UseError, EIO, "Internal error" },
 181         { viotape_ReleaseError, EIO, "Internal error" },
 182         { viotape_InvalidTape, EIO, "Invalid tape device" },
 183         { viotape_InvalidOp, EIO, "Invalid operation" },
 184         { viotape_TapeErr, EIO, "Tape error" },
 185         { viotape_AllocTimedOut, EBUSY, "Allocate timed out" },
 186         { viotape_BOTEnc, EIO, "Beginning of tape encountered" },
 187         { viotape_BlankTape, EIO, "Blank tape" },
 188         { viotape_BufferEmpty, EIO, "Buffer empty" },
 189         { viotape_CleanCartFound, ENOMEDIUM, "Cleaning cartridge found" },
 190         { viotape_CmdNotAllowed, EIO, "Command not allowed" },
 191         { viotape_CmdNotSupported, EIO, "Command not supported" },
 192         { viotape_DataCheck, EIO, "Data check" },
 193         { viotape_DecompressErr, EIO, "Decompression error" },
 194         { viotape_DeviceTimeout, EBUSY, "Device timeout" },
 195         { viotape_DeviceUnavail, EIO, "Device unavailable" },
 196         { viotape_DeviceBusy, EBUSY, "Device busy" },
 197         { viotape_EndOfMedia, ENOSPC, "End of media" },
 198         { viotape_EndOfTape, ENOSPC, "End of tape" },
 199         { viotape_EquipCheck, EIO, "Equipment check" },
 200         { viotape_InsufficientRs, EOVERFLOW, "Insufficient tape resources" },
 201         { viotape_InvalidLogBlk, EIO, "Invalid logical block location" },
 202         { viotape_LengthError, EOVERFLOW, "Length error" },
 203         { viotape_LibDoorOpen, EBUSY, "Door open" },
 204         { viotape_LoadFailure, ENOMEDIUM, "Load failure" },
 205         { viotape_NotCapable, EIO, "Not capable" },
 206         { viotape_NotOperational, EIO, "Not operational" },
 207         { viotape_NotReady, EIO, "Not ready" },
 208         { viotape_OpCancelled, EIO, "Operation cancelled" },
 209         { viotape_PhyLinkErr, EIO, "Physical link error" },
 210         { viotape_RdyNotBOT, EIO, "Ready but not beginning of tape" },
 211         { viotape_TapeMark, EIO, "Tape mark" },
 212         { viotape_WriteProt, EROFS, "Write protection error" },
 213         { 0, 0, NULL },
 214 };
 215
 216 /* Maximum number of tapes we support */
 217 #define VIOTAPE_MAX_TAPE        HVMAXARCHITECTEDVIRTUALTAPES
 218 #define MAX_PARTITIONS          4
 219
 220 /* defines for current tape state */
 221 #define VIOT_IDLE               0
 222 #define VIOT_READING            1
 223 #define VIOT_WRITING            2
 224
 225 /* Our info on the tapes */
 226 struct tape_descr {
 227         char rsrcname[10];
 228         char type[4];
 229         char model[3];
 230 };
 231
 232 static struct tape_descr *viotape_unitinfo;
 233 static dma_addr_t viotape_unitinfo_token;
 234
 235 static struct mtget viomtget[VIOTAPE_MAX_TAPE];
 236
 237 static struct class *tape_class;
 238
 239 static struct device *tape_device[VIOTAPE_MAX_TAPE];
 240
 241 /*
 242  * maintain the current state of each tape (and partition)
 243  * so that we know when to write EOF marks.
 244  */
 245 static struct {
 246         unsigned char   cur_part;
 247         unsigned char   part_stat_rwi[MAX_PARTITIONS];
 248 } state[VIOTAPE_MAX_TAPE];
 249
 250 /* We single-thread */
 251 static struct semaphore reqSem;
 252
 253 /*
 254  * When we send a request, we use this struct to get the response back
 255  * from the interrupt handler
 256  */
 257 struct op_struct {
 258         void                    *buffer;
 259         dma_addr_t              dmaaddr;
 260         size_t                  count;
 261         int                     rc;
 262         int                     non_blocking;
 263         struct completion       com;
 264         struct device           *dev;
 265         struct op_struct        *next;
 266 };
 267
 268 static spinlock_t       op_struct_list_lock;
 269 static struct op_struct *op_struct_list;
 270
 271 /* forward declaration to resolve interdependence */
 272 static int chg_state(int index, unsigned char new_state, struct file *file);
 273
 274 /* procfs support */
 275 static int proc_viotape_show(struct seq_file *m, void *v)
 276 {
 277         int i;
 278
 279         seq_printf(m, "viotape driver version " VIOTAPE_VERSION "\n");
 280         for (i = 0; i < viotape_numdev; i++) {
 281                 seq_printf(m, "viotape device %d is iSeries resource %10.10s"
 282                                 "type %4.4s, model %3.3s\n",
 283                                 i, viotape_unitinfo[i].rsrcname,
 284                                 viotape_unitinfo[i].type,
 285                                 viotape_unitinfo[i].model);
 286         }
 287         return 0;
 288 }
 289
 290 static int proc_viotape_open(struct inode *inode, struct file *file)
 291 {
 292         return single_open(file, proc_viotape_show, NULL);
 293 }
 294
 295 static const struct file_operations proc_viotape_operations = {
 296         .open           = proc_viotape_open,
 297         .read           = seq_read,
 298         .llseek         = seq_lseek,
 299         .release        = single_release,
 300 };
 301
 302 /* Decode the device minor number into its parts */
 303 void get_dev_info(struct inode *ino, struct viot_devinfo_struct *devi)
 304 {
 305         devi->devno = iminor(ino) & 0x1F;
 306         devi->mode = (iminor(ino) & 0x60) >> 5;
 307         /* if bit is set in the minor, do _not_ rewind automatically */
 308         devi->rewind = (iminor(ino) & 0x80) == 0;
 309 }
 310
 311 /* This is called only from the exit and init paths, so no need for locking */
 312 static void clear_op_struct_pool(void)
 313 {
 314         while (op_struct_list) {
 315                 struct op_struct *toFree = op_struct_list;
 316                 op_struct_list = op_struct_list->next;
 317                 kfree(toFree);
 318         }
 319 }
 320
 321 /* Likewise, this is only called from the init path */
 322 static int add_op_structs(int structs)
 323 {
 324         int i;
 325
 326         for (i = 0; i < structs; ++i) {
 327                 struct op_struct *new_struct =
 328                         kmalloc(sizeof(*new_struct), GFP_KERNEL);
 329                 if (!new_struct) {
 330                         clear_op_struct_pool();
 331                         return -ENOMEM;
 332                 }
 333                 new_struct->next = op_struct_list;
 334                 op_struct_list = new_struct;
 335         }
 336         return 0;
 337 }
 338
 339 /* Allocate an op structure from our pool */
 340 static struct op_struct *get_op_struct(void)
 341 {
 342         struct op_struct *retval;
 343         unsigned long flags;
 344
 345         spin_lock_irqsave(&op_struct_list_lock, flags);
 346         retval = op_struct_list;
 347         if (retval)
 348                 op_struct_list = retval->next;
 349         spin_unlock_irqrestore(&op_struct_list_lock, flags);
 350         if (retval) {
 351                 memset(retval, 0, sizeof(*retval));
 352                 init_completion(&retval->com);
 353         }
 354
 355         return retval;
 356 }
 357
 358 /* Return an op structure to our pool */
 359 static void free_op_struct(struct op_struct *op_struct)
 360 {
 361         unsigned long flags;
 362
 363         spin_lock_irqsave(&op_struct_list_lock, flags);
 364         op_struct->next = op_struct_list;
 365         op_struct_list = op_struct;
 366         spin_unlock_irqrestore(&op_struct_list_lock, flags);
 367 }
 368
 369 /* Map our tape return codes to errno values */
 370 int tape_rc_to_errno(int tape_rc, char *operation, int tapeno)
 371 {
 372         const struct vio_error_entry *err;
 373
 374         if (tape_rc == 0)
 375                 return 0;
 376
 377         err = vio_lookup_rc(viotape_err_table, tape_rc);
 378         printk(VIOTAPE_KERN_WARN "error(%s) 0x%04x on Device %d (%-10s): %s\n",
 379                         operation, tape_rc, tapeno,
 380                         viotape_unitinfo[tapeno].rsrcname, err->msg);
 381         return -err->errno;
 382 }
 383
 384 /* Get info on all tapes from OS/400 */
 385 static int get_viotape_info(void)
 386 {
 387         HvLpEvent_Rc hvrc;
 388         int i;
 389         size_t len = sizeof(*viotape_unitinfo) * VIOTAPE_MAX_TAPE;
 390         struct op_struct *op = get_op_struct();
 391
 392         if (op == NULL)
 393                 return -ENOMEM;
 394
 395         viotape_unitinfo = dma_alloc_coherent(iSeries_vio_dev, len,
 396                 &viotape_unitinfo_token, GFP_ATOMIC);
 397         if (viotape_unitinfo == NULL) {
 398                 free_op_struct(op);
 399                 return -ENOMEM;
 400         }
 401
 402         memset(viotape_unitinfo, 0, len);
 403
 404         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
 405                         HvLpEvent_Type_VirtualIo,
 406                         viomajorsubtype_tape | viotapegetinfo,
 407                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
 408                         viopath_sourceinst(viopath_hostLp),
 409                         viopath_targetinst(viopath_hostLp),
 410                         (u64) (unsigned long) op, VIOVERSION << 16,
 411                         viotape_unitinfo_token, len, 0, 0);
 412         if (hvrc != HvLpEvent_Rc_Good) {
 413                 printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
 414                                 (int)hvrc);
 415                 free_op_struct(op);
 416                 return -EIO;
 417         }
 418
 419         wait_for_completion(&op->com);
 420
 421         free_op_struct(op);
 422
 423         for (i = 0;
 424              ((i < VIOTAPE_MAX_TAPE) && (viotape_unitinfo[i].rsrcname[0]));
 425              i++)
 426                 viotape_numdev++;
 427         return 0;
 428 }
 429
 430
 431 /* Write */
 432 static ssize_t viotap_write(struct file *file, const char *buf,
 433                 size_t count, loff_t * ppos)
 434 {
 435         HvLpEvent_Rc hvrc;
 436         unsigned short flags = file->f_flags;
 437         int noblock = ((flags & O_NONBLOCK) != 0);
 438         ssize_t ret;
 439         struct viot_devinfo_struct devi;
 440         struct op_struct *op = get_op_struct();
 441
 442         if (op == NULL)
 443                 return -ENOMEM;
 444
 445         get_dev_info(file->f_dentry->d_inode, &devi);
 446
 447         /*
 448          * We need to make sure we can send a request.  We use
 449          * a semaphore to keep track of # requests in use.  If
 450          * we are non-blocking, make sure we don't block on the
 451          * semaphore
 452          */
 453         if (noblock) {
 454                 if (down_trylock(&reqSem)) {
 455                         ret = -EWOULDBLOCK;
 456                         goto free_op;
 457                 }
 458         } else
 459                 down(&reqSem);
 460
 461         /* Allocate a DMA buffer */
 462         op->dev = tape_device[devi.devno];
 463         op->buffer = dma_alloc_coherent(op->dev, count, &op->dmaaddr,
 464                         GFP_ATOMIC);
 465
 466         if (op->buffer == NULL) {
 467                 printk(VIOTAPE_KERN_WARN
 468                                 "error allocating dma buffer for len %ld\n",
 469                                 count);
 470                 ret = -EFAULT;
 471                 goto up_sem;
 472         }
 473
 474         /* Copy the data into the buffer */
 475         if (copy_from_user(op->buffer, buf, count)) {
 476                 printk(VIOTAPE_KERN_WARN "tape: error on copy from user\n");
 477                 ret = -EFAULT;
 478                 goto free_dma;
 479         }
 480
 481         op->non_blocking = noblock;
 482         init_completion(&op->com);
 483         op->count = count;
 484
 485         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
 486                         HvLpEvent_Type_VirtualIo,
 487                         viomajorsubtype_tape | viotapewrite,
 488                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
 489                         viopath_sourceinst(viopath_hostLp),
 490                         viopath_targetinst(viopath_hostLp),
 491                         (u64)(unsigned long)op, VIOVERSION << 16,
 492                         ((u64)devi.devno << 48) | op->dmaaddr, count, 0, 0);
 493         if (hvrc != HvLpEvent_Rc_Good) {
 494                 printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
 495                                 (int)hvrc);
 496                 ret = -EIO;
 497                 goto free_dma;
 498         }
 499
 500         if (noblock)
 501                 return count;
 502
 503         wait_for_completion(&op->com);
 504
 505         if (op->rc)
 506                 ret = tape_rc_to_errno(op->rc, "write", devi.devno);
 507         else {
 508                 chg_state(devi.devno, VIOT_WRITING, file);
 509                 ret = op->count;
 510         }
 511
 512 free_dma:
 513         dma_free_coherent(op->dev, count, op->buffer, op->dmaaddr);
 514 up_sem:
 515         up(&reqSem);
 516 free_op:
 517         free_op_struct(op);
 518         return ret;
 519 }
 520
 521 /* read */
 522 static ssize_t viotap_read(struct file *file, char *buf, size_t count,
 523                 loff_t *ptr)
 524 {
 525         HvLpEvent_Rc hvrc;
 526         unsigned short flags = file->f_flags;
 527         struct op_struct *op = get_op_struct();
 528         int noblock = ((flags & O_NONBLOCK) != 0);
 529         ssize_t ret;
 530         struct viot_devinfo_struct devi;
 531
 532         if (op == NULL)
 533                 return -ENOMEM;
 534
 535         get_dev_info(file->f_dentry->d_inode, &devi);
 536
 537         /*
 538          * We need to make sure we can send a request.  We use
 539          * a semaphore to keep track of # requests in use.  If
 540          * we are non-blocking, make sure we don't block on the
 541          * semaphore
 542          */
 543         if (noblock) {
 544                 if (down_trylock(&reqSem)) {
 545                         ret = -EWOULDBLOCK;
 546                         goto free_op;
 547                 }
 548         } else
 549                 down(&reqSem);
 550
 551         chg_state(devi.devno, VIOT_READING, file);
 552
 553         /* Allocate a DMA buffer */
 554         op->dev = tape_device[devi.devno];
 555         op->buffer = dma_alloc_coherent(op->dev, count, &op->dmaaddr,
 556                         GFP_ATOMIC);
 557         if (op->buffer == NULL) {
 558                 ret = -EFAULT;
 559                 goto up_sem;
 560         }
 561
 562         op->count = count;
 563         init_completion(&op->com);
 564
 565         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
 566                         HvLpEvent_Type_VirtualIo,
 567                         viomajorsubtype_tape | viotaperead,
 568                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
 569                         viopath_sourceinst(viopath_hostLp),
 570                         viopath_targetinst(viopath_hostLp),
 571                         (u64)(unsigned long)op, VIOVERSION << 16,
 572                         ((u64)devi.devno << 48) | op->dmaaddr, count, 0, 0);
 573         if (hvrc != HvLpEvent_Rc_Good) {
 574                 printk(VIOTAPE_KERN_WARN "tape hv error on op %d\n",
 575                                 (int)hvrc);
 576                 ret = -EIO;
 577                 goto free_dma;
 578         }
 579
 580         wait_for_completion(&op->com);
 581
 582         if (op->rc)
 583                 ret = tape_rc_to_errno(op->rc, "read", devi.devno);
 584         else {
 585                 ret = op->count;
 586                 if (ret && copy_to_user(buf, op->buffer, ret)) {
 587                         printk(VIOTAPE_KERN_WARN "error on copy_to_user\n");
 588                         ret = -EFAULT;
 589                 }
 590         }
 591
 592 free_dma:
 593         dma_free_coherent(op->dev, count, op->buffer, op->dmaaddr);
 594 up_sem:
 595         up(&reqSem);
 596 free_op:
 597         free_op_struct(op);
 598         return ret;
 599 }
 600
 601 /* ioctl */
 602 static int viotap_ioctl(struct inode *inode, struct file *file,
 603                 unsigned int cmd, unsigned long arg)
 604 {
 605         HvLpEvent_Rc hvrc;
 606         int ret;
 607         struct viot_devinfo_struct devi;
 608         struct mtop mtc;
 609         u32 myOp;
 610         struct op_struct *op = get_op_struct();
 611
 612         if (op == NULL)
 613                 return -ENOMEM;
 614
 615         get_dev_info(file->f_dentry->d_inode, &devi);
 616
 617         down(&reqSem);
 618
 619         ret = -EINVAL;
 620
 621         switch (cmd) {
 622         case MTIOCTOP:
 623                 ret = -EFAULT;
 624                 /*
 625                  * inode is null if and only if we (the kernel)
 626                  * made the request
 627                  */
 628                 if (inode == NULL)
 629                         memcpy(&mtc, (void *) arg, sizeof(struct mtop));
 630                 else if (copy_from_user((char *)&mtc, (char *)arg,
 631                                         sizeof(struct mtop)))
 632                         goto free_op;
 633
 634                 ret = -EIO;
 635                 switch (mtc.mt_op) {
 636                 case MTRESET:
 637                         myOp = VIOTAPOP_RESET;
 638                         break;
 639                 case MTFSF:
 640                         myOp = VIOTAPOP_FSF;
 641                         break;
 642                 case MTBSF:
 643                         myOp = VIOTAPOP_BSF;
 644                         break;
 645                 case MTFSR:
 646                         myOp = VIOTAPOP_FSR;
 647                         break;
 648                 case MTBSR:
 649                         myOp = VIOTAPOP_BSR;
 650                         break;
 651                 case MTWEOF:
 652                         myOp = VIOTAPOP_WEOF;
 653                         break;
 654                 case MTREW:
 655                         myOp = VIOTAPOP_REW;
 656                         break;
 657                 case MTNOP:
 658                         myOp = VIOTAPOP_NOP;
 659                         break;
 660                 case MTEOM:
 661                         myOp = VIOTAPOP_EOM;
 662                         break;
 663                 case MTERASE:
 664                         myOp = VIOTAPOP_ERASE;
 665                         break;
 666                 case MTSETBLK:
 667                         myOp = VIOTAPOP_SETBLK;
 668                         break;
 669                 case MTSETDENSITY:
 670                         myOp = VIOTAPOP_SETDENSITY;
 671                         break;
 672                 case MTTELL:
 673                         myOp = VIOTAPOP_GETPOS;
 674                         break;
 675                 case MTSEEK:
 676                         myOp = VIOTAPOP_SETPOS;
 677                         break;
 678                 case MTSETPART:
 679                         myOp = VIOTAPOP_SETPART;
 680                         break;
 681                 case MTOFFL:
 682                         myOp = VIOTAPOP_UNLOAD;
 683                         break;
 684                 default:
 685                         printk(VIOTAPE_KERN_WARN "MTIOCTOP called "
 686                                         "with invalid op 0x%x\n", mtc.mt_op);
 687                         goto free_op;
 688                 }
 689
 690                 /*
 691                  * if we moved the head, we are no longer
 692                  * reading or writing
 693                  */
 694                 switch (mtc.mt_op) {
 695                 case MTFSF:
 696                 case MTBSF:
 697                 case MTFSR:
 698                 case MTBSR:
 699                 case MTTELL:
 700                 case MTSEEK:
 701                 case MTREW:
 702                         chg_state(devi.devno, VIOT_IDLE, file);
 703                 }
 704
 705                 init_completion(&op->com);
 706                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
 707                                 HvLpEvent_Type_VirtualIo,
 708                                 viomajorsubtype_tape | viotapeop,
 709                                 HvLpEvent_AckInd_DoAck,
 710                                 HvLpEvent_AckType_ImmediateAck,
 711                                 viopath_sourceinst(viopath_hostLp),
 712                                 viopath_targetinst(viopath_hostLp),
 713                                 (u64)(unsigned long)op,
 714                                 VIOVERSION << 16,
 715                                 ((u64)devi.devno << 48), 0,
 716                                 (((u64)myOp) << 32) | mtc.mt_count, 0);
 717                 if (hvrc != HvLpEvent_Rc_Good) {
 718                         printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
 719                                         (int)hvrc);
 720                         goto free_op;
 721                 }
 722                 wait_for_completion(&op->com);
 723                 ret = tape_rc_to_errno(op->rc, "tape operation", devi.devno);
 724                 goto free_op;
 725
 726         case MTIOCGET:
 727                 ret = -EIO;
 728                 init_completion(&op->com);
 729                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
 730                                 HvLpEvent_Type_VirtualIo,
 731                                 viomajorsubtype_tape | viotapegetstatus,
 732                                 HvLpEvent_AckInd_DoAck,
 733                                 HvLpEvent_AckType_ImmediateAck,
 734                                 viopath_sourceinst(viopath_hostLp),
 735                                 viopath_targetinst(viopath_hostLp),
 736                                 (u64)(unsigned long)op, VIOVERSION << 16,
 737                                 ((u64)devi.devno << 48), 0, 0, 0);
 738                 if (hvrc != HvLpEvent_Rc_Good) {
 739                         printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
 740                                         (int)hvrc);
 741                         goto free_op;
 742                 }
 743                 wait_for_completion(&op->com);
 744
 745                 /* Operation is complete - grab the error code */
 746                 ret = tape_rc_to_errno(op->rc, "get status", devi.devno);
 747                 free_op_struct(op);
 748                 up(&reqSem);
 749
 750                 if ((ret == 0) && copy_to_user((void *)arg,
 751                                         &viomtget[devi.devno],
 752                                         sizeof(viomtget[0])))
 753                         ret = -EFAULT;
 754                 return ret;
 755         case MTIOCPOS:
 756                 printk(VIOTAPE_KERN_WARN "Got an (unsupported) MTIOCPOS\n");
 757                 break;
 758         default:
 759                 printk(VIOTAPE_KERN_WARN "got an unsupported ioctl 0x%0x\n",
 760                                 cmd);
 761                 break;
 762         }
 763
 764 free_op:
 765         free_op_struct(op);
 766         up(&reqSem);
 767         return ret;
 768 }
 769
 770 static int viotap_open(struct inode *inode, struct file *file)
 771 {
 772         HvLpEvent_Rc hvrc;
 773         struct viot_devinfo_struct devi;
 774         int ret;
 775         struct op_struct *op = get_op_struct();
 776
 777         if (op == NULL)
 778                 return -ENOMEM;
 779
 780         get_dev_info(file->f_dentry->d_inode, &devi);
 781
 782         /* Note: We currently only support one mode! */
 783         if ((devi.devno >= viotape_numdev) || (devi.mode)) {
 784                 ret = -ENODEV;
 785                 goto free_op;
 786         }
 787
 788         init_completion(&op->com);
 789
 790         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
 791                         HvLpEvent_Type_VirtualIo,
 792                         viomajorsubtype_tape | viotapeopen,
 793                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
 794                         viopath_sourceinst(viopath_hostLp),
 795                         viopath_targetinst(viopath_hostLp),
 796                         (u64)(unsigned long)op, VIOVERSION << 16,
 797                         ((u64)devi.devno << 48), 0, 0, 0);
 798         if (hvrc != 0) {
 799                 printk(VIOTAPE_KERN_WARN "bad rc on signalLpEvent %d\n",
 800                                 (int) hvrc);
 801                 ret = -EIO;
 802                 goto free_op;
 803         }
 804
 805         wait_for_completion(&op->com);
 806         ret = tape_rc_to_errno(op->rc, "open", devi.devno);
 807
 808 free_op:
 809         free_op_struct(op);
 810         return ret;
 811 }
 812
 813
 814 static int viotap_release(struct inode *inode, struct file *file)
 815 {
 816         HvLpEvent_Rc hvrc;
 817         struct viot_devinfo_struct devi;
 818         int ret = 0;
 819         struct op_struct *op = get_op_struct();
 820
 821         if (op == NULL)
 822                 return -ENOMEM;
 823         init_completion(&op->com);
 824
 825         get_dev_info(file->f_dentry->d_inode, &devi);
 826
 827         if (devi.devno >= viotape_numdev) {
 828                 ret = -ENODEV;
 829                 goto free_op;
 830         }
 831
 832         chg_state(devi.devno, VIOT_IDLE, file);
 833
 834         if (devi.rewind) {
 835                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
 836                                 HvLpEvent_Type_VirtualIo,
 837                                 viomajorsubtype_tape | viotapeop,
 838                                 HvLpEvent_AckInd_DoAck,
 839                                 HvLpEvent_AckType_ImmediateAck,
 840                                 viopath_sourceinst(viopath_hostLp),
 841                                 viopath_targetinst(viopath_hostLp),
 842                                 (u64)(unsigned long)op, VIOVERSION << 16,
 843                                 ((u64)devi.devno << 48), 0,
 844                                 ((u64)VIOTAPOP_REW) << 32, 0);
 845                 wait_for_completion(&op->com);
 846
 847                 tape_rc_to_errno(op->rc, "rewind", devi.devno);
 848         }
 849
 850         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
 851                         HvLpEvent_Type_VirtualIo,
 852                         viomajorsubtype_tape | viotapeclose,
 853                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
 854                         viopath_sourceinst(viopath_hostLp),
 855                         viopath_targetinst(viopath_hostLp),
 856                         (u64)(unsigned long)op, VIOVERSION << 16,
 857                         ((u64)devi.devno << 48), 0, 0, 0);
 858         if (hvrc != 0) {
 859                 printk(VIOTAPE_KERN_WARN "bad rc on signalLpEvent %d\n",
 860                                 (int) hvrc);
 861                 ret = -EIO;
 862                 goto free_op;
 863         }
 864
 865         wait_for_completion(&op->com);
 866
 867         if (op->rc)
 868                 printk(VIOTAPE_KERN_WARN "close failed\n");
 869
 870 free_op:
 871         free_op_struct(op);
 872         return ret;
 873 }
 874
 875 struct file_operations viotap_fops = {
 876         owner: THIS_MODULE,
 877         read: viotap_read,
 878         write: viotap_write,
 879         ioctl: viotap_ioctl,
 880         open: viotap_open,
 881         release: viotap_release,
 882 };
 883
 884 /* Handle interrupt events for tape */
 885 static void vioHandleTapeEvent(struct HvLpEvent *event)
 886 {
 887         int tapeminor;
 888         struct op_struct *op;
 889         struct viotapelpevent *tevent = (struct viotapelpevent *)event;
 890
 891         if (event == NULL) {
 892                 /* Notification that a partition went away! */
 893                 if (!viopath_isactive(viopath_hostLp)) {
 894                         /* TODO! Clean up */
 895                 }
 896                 return;
 897         }
 898
 899         tapeminor = event->xSubtype & VIOMINOR_SUBTYPE_MASK;
 900         op = (struct op_struct *)event->xCorrelationToken;
 901         switch (tapeminor) {
 902         case viotapegetinfo:
 903         case viotapeopen:
 904         case viotapeclose:
 905                 op->rc = tevent->sub_type_result;
 906                 complete(&op->com);
 907                 break;
 908         case viotaperead:
 909                 op->rc = tevent->sub_type_result;
 910                 op->count = tevent->len;
 911                 complete(&op->com);
 912                 break;
 913         case viotapewrite:
 914                 if (op->non_blocking) {
 915                         dma_free_coherent(op->dev, op->count,
 916                                         op->buffer, op->dmaaddr);
 917                         free_op_struct(op);
 918                         up(&reqSem);
 919                 } else {
 920                         op->rc = tevent->sub_type_result;
 921                         op->count = tevent->len;
 922                         complete(&op->com);
 923                 }
 924                 break;
 925         case viotapeop:
 926         case viotapegetpos:
 927         case viotapesetpos:
 928         case viotapegetstatus:
 929                 if (op) {
 930                         op->count = tevent->u.op.count;
 931                         op->rc = tevent->sub_type_result;
 932                         if (!op->non_blocking)
 933                                 complete(&op->com);
 934                 }
 935                 break;
 936         default:
 937                 printk(VIOTAPE_KERN_WARN "weird ack\n");
 938         }
 939 }
 940
 941 static int viotape_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 942 {
 943         char tapename[32];
 944         int i = vdev->unit_address;
 945         int j;
 946
 947         if (i >= viotape_numdev)
 948                 return -ENODEV;
 949
 950         tape_device[i] = &vdev->dev;
 951
 952         state[i].cur_part = 0;
 953         for (j = 0; j < MAX_PARTITIONS; ++j)
 954                 state[i].part_stat_rwi[j] = VIOT_IDLE;
 955         class_device_create(tape_class, NULL, MKDEV(VIOTAPE_MAJOR, i), NULL,
 956                         "iseries!vt%d", i);
 957         class_device_create(tape_class, NULL, MKDEV(VIOTAPE_MAJOR, i | 0x80),
 958                         NULL, "iseries!nvt%d", i);
 959         sprintf(tapename, "iseries/vt%d", i);
 960         printk(VIOTAPE_KERN_INFO "tape %s is iSeries "
 961                         "resource %10.10s type %4.4s, model %3.3s\n",
 962                         tapename, viotape_unitinfo[i].rsrcname,
 963                         viotape_unitinfo[i].type, viotape_unitinfo[i].model);
 964         return 0;
 965 }
 966
 967 static int viotape_remove(struct vio_dev *vdev)
 968 {
 969         int i = vdev->unit_address;
 970
 971         class_device_destroy(tape_class, MKDEV(VIOTAPE_MAJOR, i | 0x80));
 972         class_device_destroy(tape_class, MKDEV(VIOTAPE_MAJOR, i));
 973         return 0;
 974 }
 975
 976 /**
 977  * viotape_device_table: Used by vio.c to match devices that we
 978  * support.
 979  */
 980 static struct vio_device_id viotape_device_table[] __devinitdata = {
 981         { "byte", "IBM,iSeries-viotape" },
 982         { "", "" }
 983 };
 984 MODULE_DEVICE_TABLE(vio, viotape_device_table);
 985
 986 static struct vio_driver viotape_driver = {
 987         .id_table = viotape_device_table,
 988         .probe = viotape_probe,
 989         .remove = viotape_remove,
 990         .driver = {
 991                 .name = "viotape",
 992                 .owner = THIS_MODULE,
 993         }
 994 };
 995
 996
 997 int __init viotap_init(void)
 998 {
 999         int ret;
1000         struct proc_dir_entry *e;
1001
1002         op_struct_list = NULL;
1003         if ((ret = add_op_structs(VIOTAPE_MAXREQ)) < 0) {
1004                 printk(VIOTAPE_KERN_WARN "couldn't allocate op structs\n");
1005                 return ret;
1006         }
1007         spin_lock_init(&op_struct_list_lock);
1008
1009         sema_init(&reqSem, VIOTAPE_MAXREQ);
1010
1011         if (viopath_hostLp == HvLpIndexInvalid) {
1012                 vio_set_hostlp();
1013                 if (viopath_hostLp == HvLpIndexInvalid) {
1014                         ret = -ENODEV;
1015                         goto clear_op;
1016                 }
1017         }
1018
1019         ret = viopath_open(viopath_hostLp, viomajorsubtype_tape,
1020                         VIOTAPE_MAXREQ + 2);
1021         if (ret) {
1022                 printk(VIOTAPE_KERN_WARN
1023                                 "error on viopath_open to hostlp %d\n", ret);
1024                 ret = -EIO;
1025                 goto clear_op;
1026         }
1027
1028         printk(VIOTAPE_KERN_INFO "vers " VIOTAPE_VERSION
1029                         ", hosting partition %d\n", viopath_hostLp);
1030
1031         vio_setHandler(viomajorsubtype_tape, vioHandleTapeEvent);
1032
1033         ret = register_chrdev(VIOTAPE_MAJOR, "viotape", &viotap_fops);
1034         if (ret < 0) {
1035                 printk(VIOTAPE_KERN_WARN "Error registering viotape device\n");
1036                 goto clear_handler;
1037         }
1038
1039         tape_class = class_create(THIS_MODULE, "tape");
1040         if (IS_ERR(tape_class)) {
1041                 printk(VIOTAPE_KERN_WARN "Unable to allocat class\n");
1042                 ret = PTR_ERR(tape_class);
1043                 goto unreg_chrdev;
1044         }
1045
1046         if ((ret = get_viotape_info()) < 0) {
1047                 printk(VIOTAPE_KERN_WARN "Unable to obtain virtual device information");
1048                 goto unreg_class;
1049         }
1050
1051         ret = vio_register_driver(&viotape_driver);
1052         if (ret)
1053                 goto unreg_class;
1054
1055         e = create_proc_entry("iSeries/viotape", S_IFREG|S_IRUGO, NULL);
1056         if (e) {
1057                 e->owner = THIS_MODULE;
1058                 e->proc_fops = &proc_viotape_operations;
1059         }
1060
1061         return 0;
1062
1063 unreg_class:
1064         class_destroy(tape_class);
1065 unreg_chrdev:
1066         unregister_chrdev(VIOTAPE_MAJOR, "viotape");
1067 clear_handler:
1068         vio_clearHandler(viomajorsubtype_tape);
1069         viopath_close(viopath_hostLp, viomajorsubtype_tape, VIOTAPE_MAXREQ + 2);
1070 clear_op:
1071         clear_op_struct_pool();
1072         return ret;
1073 }
1074
1075 /* Give a new state to the tape object */
1076 static int chg_state(int index, unsigned char new_state, struct file *file)
1077 {
1078         unsigned char *cur_state =
1079             &state[index].part_stat_rwi[state[index].cur_part];
1080         int rc = 0;
1081
1082         /* if the same state, don't bother */
1083         if (*cur_state == new_state)
1084                 return 0;
1085
1086         /* write an EOF if changing from writing to some other state */
1087         if (*cur_state == VIOT_WRITING) {
1088                 struct mtop write_eof = { MTWEOF, 1 };
1089
1090                 rc = viotap_ioctl(NULL, file, MTIOCTOP,
1091                                   (unsigned long)&write_eof);
1092         }
1093         *cur_state = new_state;
1094         return rc;
1095 }
1096
1097 /* Cleanup */
1098 static void __exit viotap_exit(void)
1099 {
1100         int ret;
1101
1102         remove_proc_entry("iSeries/viotape", NULL);
1103         vio_unregister_driver(&viotape_driver);
1104         class_destroy(tape_class);
1105         ret = unregister_chrdev(VIOTAPE_MAJOR, "viotape");
1106         if (ret < 0)
1107                 printk(VIOTAPE_KERN_WARN "Error unregistering device: %d\n",
1108                                 ret);
1109         if (viotape_unitinfo)
1110                 dma_free_coherent(iSeries_vio_dev,
1111                                 sizeof(viotape_unitinfo[0]) * VIOTAPE_MAX_TAPE,
1112                                 viotape_unitinfo, viotape_unitinfo_token);
1113         viopath_close(viopath_hostLp, viomajorsubtype_tape, VIOTAPE_MAXREQ + 2);
1114         vio_clearHandler(viomajorsubtype_tape);
1115         clear_op_struct_pool();
1116 }
1117
1118 MODULE_LICENSE("GPL");
1119 module_init(viotap_init);
1120 module_exit(viotap_exit);