src/usd/usd_nt.c

   1 /*
   2  * Copyright 2000, International Business Machines Corporation and others.
   3  * All Rights Reserved.
   4  *
   5  * This software has been released under the terms of the IBM Public
   6  * License.  For details, see the LICENSE file in the top-level source
   7  * directory or online at http://www.openafs.org/dl/license10.html
   8  */
   9
  10 #include <afsconfig.h>
  11 #include <afs/param.h>
  12
  13 #include <roken.h>
  14
  15 #include <windows.h>
  16 #include <winioctl.h>
  17 #include <crtdbg.h>
  18
  19 #include <afs/errmap_nt.h>
  20 #include <afs/usd.h>
  21
  22
  23 /* WinNT-specific implementation of user space device I/O for WinNT devices. */
  24
  25 /* This module uses the following usd_handle fields:
  26  * handle -- the Win32 (HANDLE) returned by CreateFile.
  27  * fullPathName -- allocated ptr (char *) to pathname used to open device.
  28  * openFlags -- unused
  29  * privateData -- Device size (afs_uint32) in 1Kb units.
  30  */
  31
  32 /* Module-specific constants */
  33 #define TAPEOP_RETRYMAX  5
  34
  35 #define TRANSIENT_TAPE_ERROR(err) \
  36     ((err) == ERROR_BUS_RESET || (err) == ERROR_MEDIA_CHANGED)
  37
  38 /* Interface Functions */
  39
  40 static int
  41 usd_DeviceRead(usd_handle_t usd, char *buf, afs_uint32 nbytes,
  42                afs_uint32 * xferdP)
  43 {
  44     HANDLE fd = usd->handle;
  45     DWORD bytesRead;
  46
  47     if (xferdP == NULL)
  48         xferdP = &bytesRead;
  49     else
  50         *xferdP = 0;
  51
  52     if (ReadFile(fd, buf, nbytes, xferdP, NULL)) {
  53         /* read was successful */
  54         return 0;
  55     } else {
  56         /* read failed */
  57         return nterr_nt2unix(GetLastError(), EIO);
  58     }
  59 }
  60
  61 static int
  62 usd_DeviceWrite(usd_handle_t usd, char *buf, afs_uint32 nbytes,
  63                 afs_uint32 * xferdP)
  64 {
  65     HANDLE fd = usd->handle;
  66     DWORD bytesWritten;
  67     DWORD nterr;
  68
  69     if (xferdP == NULL)
  70         xferdP = &bytesWritten;
  71     else
  72         *xferdP = 0;
  73
  74     if (WriteFile(fd, buf, nbytes, xferdP, NULL)) {
  75         /* write was successful */
  76         return 0;
  77     } else {
  78         /* write failed */
  79         nterr = GetLastError();
  80         if (nterr == ERROR_END_OF_MEDIA) {
  81             *xferdP = 0;
  82             return 0;           /* indicate end of tape condition */
  83         } else
  84             return nterr_nt2unix(nterr, EIO);
  85     }
  86 }
  87
  88 /* usd_DeviceSeek --
  89  *
  90  * TODO -- Episode tries to determine the size of a disk device
  91  * empirically by binary searching for the last region it can successfully
  92  * read from the device.  It uses only USD_SEEK and USD_READ operations, so
  93  * this is portable as long as the underlying device driver fails
  94  * gracefully when an attempt is made to access past the end of the device.
  95  * Unfortunately this fails on WinNT when accessing a floppy disk.  Reads
  96  * from floppy disks at tremendous offsets blithely succeed.  Luckily, the
  97  * Win32 interface provides a way to determine the disk size.
  98  *
  99  * Add a check of the offset against the disk size to fix this problem. */
 100
 101 static int
 102 usd_DeviceSeek(usd_handle_t usd, afs_int64 reqOff, int whence,
 103                afs_int64 * curOffP)
 104 {
 105     HANDLE fd = usd->handle;
 106     DWORD method, result;
 107     DWORD error;
 108     LARGE_INTEGER offset, retOffset;
 109
 110     /* determine move method based on value of whence */
 111
 112     if (whence == SEEK_SET) {
 113         method = FILE_BEGIN;
 114     } else if (whence == SEEK_CUR) {
 115         method = FILE_CURRENT;
 116     } else if (whence == SEEK_END) {
 117         method = FILE_END;
 118     } else {
 119         /* whence is invalid */
 120         return EINVAL;
 121     }
 122     _ASSERT(sizeof(DWORD) == 4);
 123
 124     /* attempt seek */
 125
 126     if (usd->privateData) {
 127
 128         /* For disk devices that know their size, check the offset against the
 129          * limit provided by DeviceIoControl(). */
 130
 131         afs_int64 k = ((afs_uint32) usd->privateData);
 132
 133         if (reqOff >= (k << 10))
 134             return EINVAL;
 135     }
 136
 137     offset.QuadPart = reqOff;
 138
 139     result = SetFilePointerEx(fd, offset, &retOffset, method);
 140     if (result == 0 && (error = GetLastError()) != NO_ERROR)
 141         return nterr_nt2unix(error, EIO);
 142
 143     if (curOffP)
 144         *curOffP = retOffset.QuadPart;
 145
 146     return 0;
 147 }
 148
 149 static int
 150 usd_DeviceIoctl(usd_handle_t usd, int req, void *arg)
 151 {
 152     HANDLE fd = usd->handle;
 153     LARGE_INTEGER size;
 154     DWORD result;
 155     DWORD hiPart;
 156     int code = 0;
 157
 158     switch (req) {
 159     case USD_IOCTL_GETTYPE:
 160         {
 161             int mode;
 162
 163             BY_HANDLE_FILE_INFORMATION info;
 164             DISK_GEOMETRY geom;
 165             DWORD nbytes;
 166             DWORD fileError = 0;
 167             DWORD diskError = 0;
 168
 169             if (!GetFileInformationByHandle(fd, &info))
 170                 fileError = GetLastError();
 171
 172             if (!DeviceIoControl
 173                 (fd, IOCTL_DISK_GET_DRIVE_GEOMETRY, NULL, 0, &geom,
 174                  sizeof(geom), &nbytes, NULL))
 175                 diskError = GetLastError();
 176
 177             mode = 0;
 178             if ((fileError == ERROR_INVALID_PARAMETER
 179                  || fileError == ERROR_INVALID_FUNCTION)
 180                 && diskError == 0) {
 181                 mode = S_IFCHR; /* a disk device */
 182                 if ((afs_uint32) (usd->privateData) == 0) {
 183
 184                     /* Fill in the device size from disk geometry info.  Note
 185                      * that this is the whole disk, not just the partition, so
 186                      * it will serve only as an upper bound. */
 187
 188                     DWORDLONG size = geom.Cylinders.QuadPart;
 189                     afs_uint32 k;
 190                     size *= geom.TracksPerCylinder;
 191                     size *= geom.SectorsPerTrack;
 192                     size *= geom.BytesPerSector;
 193                     if (size == 0)
 194                         return ENODEV;
 195                     size >>= 10;        /* convert to Kilobytes */
 196                     if (size >> 31)
 197                         k = 0x7fffffff;
 198                     else
 199                         k = (afs_uint32) size;
 200                     usd->privateData = (void *)k;
 201                 }
 202             } else if (diskError == ERROR_INVALID_PARAMETER && fileError == 0)
 203                 mode = S_IFREG; /* a regular file */
 204             else {
 205                 /* check to see if device is a tape drive */
 206                 result = GetTapeStatus(fd);
 207
 208                 if (result != ERROR_INVALID_FUNCTION
 209                     && result != ERROR_INVALID_PARAMETER) {
 210                     /* looks like a tape drive */
 211                     mode = S_IFCHR;
 212                 }
 213             }
 214
 215             if (!mode)
 216                 return EINVAL;
 217             *(int *)arg = mode;
 218             return 0;
 219         }
 220
 221     case USD_IOCTL_GETDEV:
 222         return EINVAL;
 223         *(dev_t *) arg = 0;
 224         break;
 225
 226     case USD_IOCTL_GETFULLNAME:
 227         *(char **)arg = usd->fullPathName;
 228         break;
 229
 230     case USD_IOCTL_GETSIZE:
 231         if (!GetFileSizeEx(fd, &size) && (code = GetLastError()) != NO_ERROR)
 232             return nterr_nt2unix(code, EIO);
 233
 234         *(afs_int64 *) arg = size.QuadPart;
 235
 236         return 0;
 237
 238     case USD_IOCTL_SETSIZE:
 239         code = usd_DeviceSeek(usd, *(afs_int64 *) arg, SEEK_SET, NULL);
 240         if (!code) {
 241             if (!SetEndOfFile(fd))
 242                 code = nterr_nt2unix(GetLastError(), EIO);
 243         }
 244         return code;
 245
 246     case USD_IOCTL_TAPEOPERATION:
 247         {
 248             TAPE_GET_MEDIA_PARAMETERS mediaParam;
 249             TAPE_GET_DRIVE_PARAMETERS driveParam;
 250             DWORD mediaParamSize = sizeof(TAPE_GET_MEDIA_PARAMETERS);
 251             DWORD driveParamSize = sizeof(TAPE_GET_DRIVE_PARAMETERS);
 252             DWORD reloffset, fmarkType;
 253             int retrycount;
 254             usd_tapeop_t *tapeOpp = (usd_tapeop_t *) arg;
 255
 256             /* Execute specified tape command */
 257
 258             switch (tapeOpp->tp_op) {
 259             case USDTAPE_WEOF:
 260                 /* Determine type of filemark supported by device */
 261                 result =
 262                     GetTapeParameters(fd, GET_TAPE_DRIVE_INFORMATION,
 263                                       &driveParamSize, &driveParam);
 264
 265                 if (result == NO_ERROR) {
 266                     /* drive must support either normal or long filemarks */
 267                     if (driveParam.FeaturesHigh & TAPE_DRIVE_WRITE_FILEMARKS) {
 268                         fmarkType = TAPE_FILEMARKS;
 269                     } else if (driveParam.
 270                                FeaturesHigh & TAPE_DRIVE_WRITE_LONG_FMKS) {
 271                         fmarkType = TAPE_LONG_FILEMARKS;
 272                     } else {
 273                         result = ERROR_NOT_SUPPORTED;
 274                     }
 275                 }
 276
 277                 /* Write specified number of filemarks */
 278                 if (result == NO_ERROR) {
 279                     result =
 280                         WriteTapemark(fd, fmarkType, tapeOpp->tp_count,
 281                                       FALSE);
 282                 }
 283                 break;
 284
 285             case USDTAPE_REW:
 286                 /* Rewind tape */
 287                 retrycount = 0;
 288                 do {
 289                     /* absorb non-persistant errors, e.g. ERROR_MEDIA_CHANGED. */
 290                     result = SetTapePosition(fd, TAPE_REWIND, 0, 0, 0, FALSE);
 291                 } while ((result != NO_ERROR)
 292                          && (retrycount++ < TAPEOP_RETRYMAX));
 293
 294                 break;
 295
 296             case USDTAPE_FSF:
 297             case USDTAPE_BSF:
 298                 /* Space over specified number of file marks */
 299                 if (tapeOpp->tp_count < 0) {
 300                     result = ERROR_INVALID_PARAMETER;
 301                 } else {
 302                     if (tapeOpp->tp_op == USDTAPE_FSF) {
 303                         reloffset = tapeOpp->tp_count;
 304                     } else {
 305                         reloffset = 0 - tapeOpp->tp_count;
 306                     }
 307
 308                     result =
 309                         SetTapePosition(fd, TAPE_SPACE_FILEMARKS, 0,
 310                                         reloffset, 0, FALSE);
 311                 }
 312                 break;
 313
 314             case USDTAPE_PREPARE:
 315                 /* Prepare tape drive for operation; do after open. */
 316
 317                 retrycount = 0;
 318                 do {
 319                     /* absorb non-persistant errors */
 320                     if (retrycount > 0) {
 321                         Sleep(2 * 1000);
 322                     }
 323                     result = PrepareTape(fd, TAPE_LOCK, FALSE);
 324                 } while (TRANSIENT_TAPE_ERROR(result)
 325                          && retrycount++ < TAPEOP_RETRYMAX);
 326
 327                 if (result == NO_ERROR) {
 328                     retrycount = 0;
 329                     do {
 330                         /* absorb non-persistant errors */
 331                         if (retrycount > 0) {
 332                             Sleep(2 * 1000);
 333                         }
 334                         result = GetTapeStatus(fd);
 335                     } while (TRANSIENT_TAPE_ERROR(result)
 336                              && retrycount++ < TAPEOP_RETRYMAX);
 337                 }
 338
 339                 /* Querying media/drive info seems to clear bad tape state */
 340                 if (result == NO_ERROR) {
 341                     result =
 342                         GetTapeParameters(fd, GET_TAPE_MEDIA_INFORMATION,
 343                                           &mediaParamSize, &mediaParam);
 344                 }
 345
 346                 if (result == NO_ERROR) {
 347                     result =
 348                         GetTapeParameters(fd, GET_TAPE_DRIVE_INFORMATION,
 349                                           &driveParamSize, &driveParam);
 350                 }
 351                 break;
 352
 353             case USDTAPE_SHUTDOWN:
 354                 /* Decommission tape drive after operation; do before close. */
 355                 result = PrepareTape(fd, TAPE_UNLOCK, FALSE);
 356                 break;
 357
 358             default:
 359                 /* Invalid command */
 360                 result = ERROR_INVALID_PARAMETER;
 361                 break;
 362             }
 363
 364             if (result == NO_ERROR) {
 365                 return (0);
 366             } else {
 367                 return nterr_nt2unix(result, EIO);
 368             }
 369         }
 370
 371     case USD_IOCTL_GETBLKSIZE:
 372         *((long *)arg) = (long)4096;
 373         return 0;
 374
 375     default:
 376         return EINVAL;
 377     }
 378     return code;
 379 }
 380
 381
 382 static int
 383 usd_DeviceClose(usd_handle_t usd)
 384 {
 385     HANDLE fd = usd->handle;
 386     int code;
 387
 388     if (CloseHandle(fd))
 389         code = 0;
 390     else
 391         code = nterr_nt2unix(GetLastError(), EIO);
 392
 393     if (usd->fullPathName)
 394         free(usd->fullPathName);
 395     free(usd);
 396
 397     return code;
 398 }
 399
 400 /*
 401  * usd_DeviceOpen() -- open WinNT device (or regular file)
 402  *
 403  * PARAMETERS --
 404  *     oflag -- Various combinations of USD_OPEN_XXX defined in usd.h.
 405  *     pmode -- ignored; file's security descriptor set to default on create.
 406  *     usdP -- if NULL device is immediately closed after being opened.
 407  *         Otherwise, *usdP is set to the user space device handle.
 408  *
 409  * RETURN CODES -- On error a unix-style errno value is *returned*.  Else zero.
 410  */
 411
 412 static int
 413 usd_DeviceOpen(const char *path, int oflag, int pmode, usd_handle_t * usdP)
 414 {
 415     HANDLE devhandle;
 416     DWORD access, share, create, attr;
 417     usd_handle_t usd;
 418     int mode;                   /* type of opened object */
 419     int code;
 420
 421     if (usdP)
 422         *usdP = NULL;
 423
 424     /* set access as specified in oflag */
 425
 426     if (oflag & USD_OPEN_SYNC)
 427         attr = FILE_FLAG_WRITE_THROUGH;
 428     else
 429         attr = 0;
 430
 431     /* should we always set:
 432      *     FILE_FLAG_NO_BUFFERING?
 433      *     FILE_FLAG_RANDOM_ACCESS?
 434      */
 435
 436     access = GENERIC_READ;
 437     if (oflag & USD_OPEN_RDWR)
 438         access |= GENERIC_WRITE;
 439
 440     /* set create as specified in oflag */
 441
 442     if (oflag & USD_OPEN_CREATE) {
 443         /* must be opening a file; allow it to be created */
 444         create = OPEN_ALWAYS;
 445     } else {
 446         create = OPEN_EXISTING;
 447     }
 448
 449
 450     if (oflag & (USD_OPEN_RLOCK | USD_OPEN_WLOCK)) {
 451
 452         /* make sure both lock bits aren't set */
 453         _ASSERT(~oflag & (USD_OPEN_RLOCK | USD_OPEN_WLOCK));
 454
 455         share =
 456             ((oflag & USD_OPEN_RLOCK) ? FILE_SHARE_READ : 0 /*no sharing */ );
 457
 458     } else {
 459         share = FILE_SHARE_READ + FILE_SHARE_WRITE;
 460     }
 461
 462     /* attempt to open the device/file */
 463
 464     devhandle = CreateFile(path, access, share, NULL, create, attr, NULL);
 465
 466     if (devhandle == INVALID_HANDLE_VALUE)
 467         return nterr_nt2unix(GetLastError(), EIO);
 468
 469     usd = calloc(1, sizeof(*usd));
 470
 471     _ASSERT(sizeof(devhandle) <= sizeof(usd->handle));
 472     usd->handle = (void *)devhandle;
 473
 474     usd->read = usd_DeviceRead;
 475     usd->write = usd_DeviceWrite;
 476     usd->seek = usd_DeviceSeek;
 477     usd->ioctl = usd_DeviceIoctl;
 478     usd->close = usd_DeviceClose;
 479
 480     usd->fullPathName = strdup(path);
 481     usd->openFlags = oflag;
 482
 483     /* For devices, this is the first real reference, so many errors show up
 484      * here.  Also this call also sets the size (stored in usd->privateData)
 485      * based on the results of the call to DeviceIoControl(). */
 486     code = USD_IOCTL(usd, USD_IOCTL_GETTYPE, &mode);
 487
 488
 489     /* If we're trying to obtain a write lock on a real disk, then the
 490      * aggregate must not be attached by the kernel.  If so, unlock it
 491      * and fail.
 492      * WARNING: The code to check for the above has been removed when this
 493      * file was ported from DFS src. It should be put back if
 494      * this library is used to access hard disks
 495      */
 496
 497     if (code == 0 && usdP)
 498         *usdP = usd;
 499     else
 500         usd_DeviceClose(usd);
 501     return code;
 502 }
 503
 504 int
 505 usd_Open(const char *path, int oflag, int mode, usd_handle_t * usdP)
 506 {
 507     return usd_DeviceOpen(path, oflag, mode, usdP);
 508 }
 509
 510 static int
 511 usd_DeviceDummyClose(usd_handle_t usd)
 512 {
 513     free(usd);
 514     return 0;
 515 }
 516
 517 static int
 518 usd_DeviceStandardInput(usd_handle_t * usdP)
 519 {
 520     usd_handle_t usd;
 521
 522     if (usdP)
 523         *usdP = NULL;
 524
 525     usd = calloc(1, sizeof(*usd));
 526     usd->handle = (void *)0;
 527     usd->read = usd_DeviceRead;
 528     usd->write = usd_DeviceWrite;
 529     usd->seek = usd_DeviceSeek;
 530     usd->ioctl = usd_DeviceIoctl;
 531     usd->close = usd_DeviceDummyClose;
 532     usd->fullPathName = "STDIN";
 533     usd->openFlags = 0;
 534
 535     return 0;
 536 }
 537
 538 int
 539 usd_StandardInput(usd_handle_t * usdP)
 540 {
 541     return usd_DeviceStandardInput(usdP);
 542 }
 543
 544 static int
 545 usd_DeviceStandardOutput(usd_handle_t * usdP)
 546 {
 547     usd_handle_t usd;
 548
 549     if (usdP)
 550         *usdP = NULL;
 551
 552     usd = calloc(1, sizeof(*usd));
 553     usd->handle = (void *)1;
 554     usd->read = usd_DeviceRead;
 555     usd->write = usd_DeviceWrite;
 556     usd->seek = usd_DeviceSeek;
 557     usd->ioctl = usd_DeviceIoctl;
 558     usd->close = usd_DeviceDummyClose;
 559     usd->fullPathName = "STDOUT";
 560     usd->openFlags = 0;
 561
 562     return 0;
 563 }
 564
 565 int
 566 usd_StandardOutput(usd_handle_t * usdP)
 567 {
 568     return usd_DeviceStandardOutput(usdP);
 569 }