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