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