drivers/mtd/mtdchar.c

   1 /*
   2  * Character-device access to raw MTD devices.
   3  *
   4  */
   5
   6 #include <linux/device.h>
   7 #include <linux/fs.h>
   8 #include <linux/mm.h>
   9 #include <linux/err.h>
  10 #include <linux/init.h>
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/slab.h>
  14 #include <linux/sched.h>
  15 #include <linux/smp_lock.h>
  16 #include <linux/backing-dev.h>
  17 #include <linux/compat.h>
  18
  19 #include <linux/mtd/mtd.h>
  20 #include <linux/mtd/compatmac.h>
  21
  22 #include <asm/uaccess.h>
  23
  24
  25 /*
  26  * Data structure to hold the pointer to the mtd device as well
  27  * as mode information ofr various use cases.
  28  */
  29 struct mtd_file_info {
  30         struct mtd_info *mtd;
  31         enum mtd_file_modes mode;
  32 };
  33
  34 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
  35 {
  36         struct mtd_file_info *mfi = file->private_data;
  37         struct mtd_info *mtd = mfi->mtd;
  38
  39         switch (orig) {
  40         case SEEK_SET:
  41                 break;
  42         case SEEK_CUR:
  43                 offset += file->f_pos;
  44                 break;
  45         case SEEK_END:
  46                 offset += mtd->size;
  47                 break;
  48         default:
  49                 return -EINVAL;
  50         }
  51
  52         if (offset >= 0 && offset <= mtd->size)
  53                 return file->f_pos = offset;
  54
  55         return -EINVAL;
  56 }
  57
  58
  59
  60 static int mtd_open(struct inode *inode, struct file *file)
  61 {
  62         int minor = iminor(inode);
  63         int devnum = minor >> 1;
  64         int ret = 0;
  65         struct mtd_info *mtd;
  66         struct mtd_file_info *mfi;
  67
  68         DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
  69
  70         if (devnum >= MAX_MTD_DEVICES)
  71                 return -ENODEV;
  72
  73         /* You can't open the RO devices RW */
  74         if ((file->f_mode & FMODE_WRITE) && (minor & 1))
  75                 return -EACCES;
  76
  77         lock_kernel();
  78         mtd = get_mtd_device(NULL, devnum);
  79
  80         if (IS_ERR(mtd)) {
  81                 ret = PTR_ERR(mtd);
  82                 goto out;
  83         }
  84
  85         if (mtd->type == MTD_ABSENT) {
  86                 put_mtd_device(mtd);
  87                 ret = -ENODEV;
  88                 goto out;
  89         }
  90
  91         if (mtd->backing_dev_info)
  92                 file->f_mapping->backing_dev_info = mtd->backing_dev_info;
  93
  94         /* You can't open it RW if it's not a writeable device */
  95         if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
  96                 put_mtd_device(mtd);
  97                 ret = -EACCES;
  98                 goto out;
  99         }
 100
 101         mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
 102         if (!mfi) {
 103                 put_mtd_device(mtd);
 104                 ret = -ENOMEM;
 105                 goto out;
 106         }
 107         mfi->mtd = mtd;
 108         file->private_data = mfi;
 109
 110 out:
 111         unlock_kernel();
 112         return ret;
 113 } /* mtd_open */
 114
 115 /*====================================================================*/
 116
 117 static int mtd_close(struct inode *inode, struct file *file)
 118 {
 119         struct mtd_file_info *mfi = file->private_data;
 120         struct mtd_info *mtd = mfi->mtd;
 121
 122         DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
 123
 124         /* Only sync if opened RW */
 125         if ((file->f_mode & FMODE_WRITE) && mtd->sync)
 126                 mtd->sync(mtd);
 127
 128         put_mtd_device(mtd);
 129         file->private_data = NULL;
 130         kfree(mfi);
 131
 132         return 0;
 133 } /* mtd_close */
 134
 135 /* FIXME: This _really_ needs to die. In 2.5, we should lock the
 136    userspace buffer down and use it directly with readv/writev.
 137 */
 138 #define MAX_KMALLOC_SIZE 0x20000
 139
 140 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
 141 {
 142         struct mtd_file_info *mfi = file->private_data;
 143         struct mtd_info *mtd = mfi->mtd;
 144         size_t retlen=0;
 145         size_t total_retlen=0;
 146         int ret=0;
 147         int len;
 148         char *kbuf;
 149
 150         DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
 151
 152         if (*ppos + count > mtd->size)
 153                 count = mtd->size - *ppos;
 154
 155         if (!count)
 156                 return 0;
 157
 158         /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
 159            and pass them directly to the MTD functions */
 160
 161         if (count > MAX_KMALLOC_SIZE)
 162                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
 163         else
 164                 kbuf=kmalloc(count, GFP_KERNEL);
 165
 166         if (!kbuf)
 167                 return -ENOMEM;
 168
 169         while (count) {
 170
 171                 if (count > MAX_KMALLOC_SIZE)
 172                         len = MAX_KMALLOC_SIZE;
 173                 else
 174                         len = count;
 175
 176                 switch (mfi->mode) {
 177                 case MTD_MODE_OTP_FACTORY:
 178                         ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 179                         break;
 180                 case MTD_MODE_OTP_USER:
 181                         ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 182                         break;
 183                 case MTD_MODE_RAW:
 184                 {
 185                         struct mtd_oob_ops ops;
 186
 187                         ops.mode = MTD_OOB_RAW;
 188                         ops.datbuf = kbuf;
 189                         ops.oobbuf = NULL;
 190                         ops.len = len;
 191
 192                         ret = mtd->read_oob(mtd, *ppos, &ops);
 193                         retlen = ops.retlen;
 194                         break;
 195                 }
 196                 default:
 197                         ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
 198                 }
 199                 /* Nand returns -EBADMSG on ecc errors, but it returns
 200                  * the data. For our userspace tools it is important
 201                  * to dump areas with ecc errors !
 202                  * For kernel internal usage it also might return -EUCLEAN
 203                  * to signal the caller that a bitflip has occured and has
 204                  * been corrected by the ECC algorithm.
 205                  * Userspace software which accesses NAND this way
 206                  * must be aware of the fact that it deals with NAND
 207                  */
 208                 if (!ret || (ret == -EUCLEAN) || (ret == -EBADMSG)) {
 209                         *ppos += retlen;
 210                         if (copy_to_user(buf, kbuf, retlen)) {
 211                                 kfree(kbuf);
 212                                 return -EFAULT;
 213                         }
 214                         else
 215                                 total_retlen += retlen;
 216
 217                         count -= retlen;
 218                         buf += retlen;
 219                         if (retlen == 0)
 220                                 count = 0;
 221                 }
 222                 else {
 223                         kfree(kbuf);
 224                         return ret;
 225                 }
 226
 227         }
 228
 229         kfree(kbuf);
 230         return total_retlen;
 231 } /* mtd_read */
 232
 233 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
 234 {
 235         struct mtd_file_info *mfi = file->private_data;
 236         struct mtd_info *mtd = mfi->mtd;
 237         char *kbuf;
 238         size_t retlen;
 239         size_t total_retlen=0;
 240         int ret=0;
 241         int len;
 242
 243         DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
 244
 245         if (*ppos == mtd->size)
 246                 return -ENOSPC;
 247
 248         if (*ppos + count > mtd->size)
 249                 count = mtd->size - *ppos;
 250
 251         if (!count)
 252                 return 0;
 253
 254         if (count > MAX_KMALLOC_SIZE)
 255                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
 256         else
 257                 kbuf=kmalloc(count, GFP_KERNEL);
 258
 259         if (!kbuf)
 260                 return -ENOMEM;
 261
 262         while (count) {
 263
 264                 if (count > MAX_KMALLOC_SIZE)
 265                         len = MAX_KMALLOC_SIZE;
 266                 else
 267                         len = count;
 268
 269                 if (copy_from_user(kbuf, buf, len)) {
 270                         kfree(kbuf);
 271                         return -EFAULT;
 272                 }
 273
 274                 switch (mfi->mode) {
 275                 case MTD_MODE_OTP_FACTORY:
 276                         ret = -EROFS;
 277                         break;
 278                 case MTD_MODE_OTP_USER:
 279                         if (!mtd->write_user_prot_reg) {
 280                                 ret = -EOPNOTSUPP;
 281                                 break;
 282                         }
 283                         ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 284                         break;
 285
 286                 case MTD_MODE_RAW:
 287                 {
 288                         struct mtd_oob_ops ops;
 289
 290                         ops.mode = MTD_OOB_RAW;
 291                         ops.datbuf = kbuf;
 292                         ops.oobbuf = NULL;
 293                         ops.len = len;
 294
 295                         ret = mtd->write_oob(mtd, *ppos, &ops);
 296                         retlen = ops.retlen;
 297                         break;
 298                 }
 299
 300                 default:
 301                         ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
 302                 }
 303                 if (!ret) {
 304                         *ppos += retlen;
 305                         total_retlen += retlen;
 306                         count -= retlen;
 307                         buf += retlen;
 308                 }
 309                 else {
 310                         kfree(kbuf);
 311                         return ret;
 312                 }
 313         }
 314
 315         kfree(kbuf);
 316         return total_retlen;
 317 } /* mtd_write */
 318
 319 /*======================================================================
 320
 321     IOCTL calls for getting device parameters.
 322
 323 ======================================================================*/
 324 static void mtdchar_erase_callback (struct erase_info *instr)
 325 {
 326         wake_up((wait_queue_head_t *)instr->priv);
 327 }
 328
 329 #ifdef CONFIG_HAVE_MTD_OTP
 330 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
 331 {
 332         struct mtd_info *mtd = mfi->mtd;
 333         int ret = 0;
 334
 335         switch (mode) {
 336         case MTD_OTP_FACTORY:
 337                 if (!mtd->read_fact_prot_reg)
 338                         ret = -EOPNOTSUPP;
 339                 else
 340                         mfi->mode = MTD_MODE_OTP_FACTORY;
 341                 break;
 342         case MTD_OTP_USER:
 343                 if (!mtd->read_fact_prot_reg)
 344                         ret = -EOPNOTSUPP;
 345                 else
 346                         mfi->mode = MTD_MODE_OTP_USER;
 347                 break;
 348         default:
 349                 ret = -EINVAL;
 350         case MTD_OTP_OFF:
 351                 break;
 352         }
 353         return ret;
 354 }
 355 #else
 356 # define otp_select_filemode(f,m)       -EOPNOTSUPP
 357 #endif
 358
 359 static int mtd_do_writeoob(struct file *file, struct mtd_info *mtd,
 360         uint64_t start, uint32_t length, void __user *ptr,
 361         uint32_t __user *retp)
 362 {
 363         struct mtd_oob_ops ops;
 364         uint32_t retlen;
 365         int ret = 0;
 366
 367         if (!(file->f_mode & FMODE_WRITE))
 368                 return -EPERM;
 369
 370         if (length > 4096)
 371                 return -EINVAL;
 372
 373         if (!mtd->write_oob)
 374                 ret = -EOPNOTSUPP;
 375         else
 376                 ret = access_ok(VERIFY_READ, ptr, length) ? 0 : EFAULT;
 377
 378         if (ret)
 379                 return ret;
 380
 381         ops.ooblen = length;
 382         ops.ooboffs = start & (mtd->oobsize - 1);
 383         ops.datbuf = NULL;
 384         ops.mode = MTD_OOB_PLACE;
 385
 386         if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
 387                 return -EINVAL;
 388
 389         ops.oobbuf = kmalloc(length, GFP_KERNEL);
 390         if (!ops.oobbuf)
 391                 return -ENOMEM;
 392
 393         if (copy_from_user(ops.oobbuf, ptr, length)) {
 394                 kfree(ops.oobbuf);
 395                 return -EFAULT;
 396         }
 397
 398         start &= ~((uint64_t)mtd->oobsize - 1);
 399         ret = mtd->write_oob(mtd, start, &ops);
 400
 401         if (ops.oobretlen > 0xFFFFFFFFU)
 402                 ret = -EOVERFLOW;
 403         retlen = ops.oobretlen;
 404         if (copy_to_user(retp, &retlen, sizeof(length)))
 405                 ret = -EFAULT;
 406
 407         kfree(ops.oobbuf);
 408         return ret;
 409 }
 410
 411 static int mtd_do_readoob(struct mtd_info *mtd, uint64_t start,
 412         uint32_t length, void __user *ptr, uint32_t __user *retp)
 413 {
 414         struct mtd_oob_ops ops;
 415         int ret = 0;
 416
 417         if (length > 4096)
 418                 return -EINVAL;
 419
 420         if (!mtd->read_oob)
 421                 ret = -EOPNOTSUPP;
 422         else
 423                 ret = access_ok(VERIFY_WRITE, ptr,
 424                                 length) ? 0 : -EFAULT;
 425         if (ret)
 426                 return ret;
 427
 428         ops.ooblen = length;
 429         ops.ooboffs = start & (mtd->oobsize - 1);
 430         ops.datbuf = NULL;
 431         ops.mode = MTD_OOB_PLACE;
 432
 433         if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
 434                 return -EINVAL;
 435
 436         ops.oobbuf = kmalloc(length, GFP_KERNEL);
 437         if (!ops.oobbuf)
 438                 return -ENOMEM;
 439
 440         start &= ~((uint64_t)mtd->oobsize - 1);
 441         ret = mtd->read_oob(mtd, start, &ops);
 442
 443         if (put_user(ops.oobretlen, retp))
 444                 ret = -EFAULT;
 445         else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
 446                                             ops.oobretlen))
 447                 ret = -EFAULT;
 448
 449         kfree(ops.oobbuf);
 450         return ret;
 451 }
 452
 453 static int mtd_ioctl(struct inode *inode, struct file *file,
 454                      u_int cmd, u_long arg)
 455 {
 456         struct mtd_file_info *mfi = file->private_data;
 457         struct mtd_info *mtd = mfi->mtd;
 458         void __user *argp = (void __user *)arg;
 459         int ret = 0;
 460         u_long size;
 461         struct mtd_info_user info;
 462
 463         DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
 464
 465         size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
 466         if (cmd & IOC_IN) {
 467                 if (!access_ok(VERIFY_READ, argp, size))
 468                         return -EFAULT;
 469         }
 470         if (cmd & IOC_OUT) {
 471                 if (!access_ok(VERIFY_WRITE, argp, size))
 472                         return -EFAULT;
 473         }
 474
 475         switch (cmd) {
 476         case MEMGETREGIONCOUNT:
 477                 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
 478                         return -EFAULT;
 479                 break;
 480
 481         case MEMGETREGIONINFO:
 482         {
 483                 uint32_t ur_idx;
 484                 struct mtd_erase_region_info *kr;
 485                 struct region_info_user *ur = (struct region_info_user *) argp;
 486
 487                 if (get_user(ur_idx, &(ur->regionindex)))
 488                         return -EFAULT;
 489
 490                 kr = &(mtd->eraseregions[ur_idx]);
 491
 492                 if (put_user(kr->offset, &(ur->offset))
 493                     || put_user(kr->erasesize, &(ur->erasesize))
 494                     || put_user(kr->numblocks, &(ur->numblocks)))
 495                         return -EFAULT;
 496
 497                 break;
 498         }
 499
 500         case MEMGETINFO:
 501                 info.type       = mtd->type;
 502                 info.flags      = mtd->flags;
 503                 info.size       = mtd->size;
 504                 info.erasesize  = mtd->erasesize;
 505                 info.writesize  = mtd->writesize;
 506                 info.oobsize    = mtd->oobsize;
 507                 /* The below fields are obsolete */
 508                 info.ecctype    = -1;
 509                 info.eccsize    = 0;
 510                 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
 511                         return -EFAULT;
 512                 break;
 513
 514         case MEMERASE:
 515         case MEMERASE64:
 516         {
 517                 struct erase_info *erase;
 518
 519                 if(!(file->f_mode & FMODE_WRITE))
 520                         return -EPERM;
 521
 522                 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
 523                 if (!erase)
 524                         ret = -ENOMEM;
 525                 else {
 526                         wait_queue_head_t waitq;
 527                         DECLARE_WAITQUEUE(wait, current);
 528
 529                         init_waitqueue_head(&waitq);
 530
 531                         if (cmd == MEMERASE64) {
 532                                 struct erase_info_user64 einfo64;
 533
 534                                 if (copy_from_user(&einfo64, argp,
 535                                             sizeof(struct erase_info_user64))) {
 536                                         kfree(erase);
 537                                         return -EFAULT;
 538                                 }
 539                                 erase->addr = einfo64.start;
 540                                 erase->len = einfo64.length;
 541                         } else {
 542                                 struct erase_info_user einfo32;
 543
 544                                 if (copy_from_user(&einfo32, argp,
 545                                             sizeof(struct erase_info_user))) {
 546                                         kfree(erase);
 547                                         return -EFAULT;
 548                                 }
 549                                 erase->addr = einfo32.start;
 550                                 erase->len = einfo32.length;
 551                         }
 552                         erase->mtd = mtd;
 553                         erase->callback = mtdchar_erase_callback;
 554                         erase->priv = (unsigned long)&waitq;
 555
 556                         /*
 557                           FIXME: Allow INTERRUPTIBLE. Which means
 558                           not having the wait_queue head on the stack.
 559
 560                           If the wq_head is on the stack, and we
 561                           leave because we got interrupted, then the
 562                           wq_head is no longer there when the
 563                           callback routine tries to wake us up.
 564                         */
 565                         ret = mtd->erase(mtd, erase);
 566                         if (!ret) {
 567                                 set_current_state(TASK_UNINTERRUPTIBLE);
 568                                 add_wait_queue(&waitq, &wait);
 569                                 if (erase->state != MTD_ERASE_DONE &&
 570                                     erase->state != MTD_ERASE_FAILED)
 571                                         schedule();
 572                                 remove_wait_queue(&waitq, &wait);
 573                                 set_current_state(TASK_RUNNING);
 574
 575                                 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
 576                         }
 577                         kfree(erase);
 578                 }
 579                 break;
 580         }
 581
 582         case MEMWRITEOOB:
 583         {
 584                 struct mtd_oob_buf buf;
 585                 struct mtd_oob_buf __user *buf_user = argp;
 586
 587                 /* NOTE: writes return length to buf_user->length */
 588                 if (copy_from_user(&buf, argp, sizeof(buf)))
 589                         ret = -EFAULT;
 590                 else
 591                         ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
 592                                 buf.ptr, &buf_user->length);
 593                 break;
 594         }
 595
 596         case MEMREADOOB:
 597         {
 598                 struct mtd_oob_buf buf;
 599                 struct mtd_oob_buf __user *buf_user = argp;
 600
 601                 /* NOTE: writes return length to buf_user->start */
 602                 if (copy_from_user(&buf, argp, sizeof(buf)))
 603                         ret = -EFAULT;
 604                 else
 605                         ret = mtd_do_readoob(mtd, buf.start, buf.length,
 606                                 buf.ptr, &buf_user->start);
 607                 break;
 608         }
 609
 610         case MEMLOCK:
 611         {
 612                 struct erase_info_user einfo;
 613
 614                 if (copy_from_user(&einfo, argp, sizeof(einfo)))
 615                         return -EFAULT;
 616
 617                 if (!mtd->lock)
 618                         ret = -EOPNOTSUPP;
 619                 else
 620                         ret = mtd->lock(mtd, einfo.start, einfo.length);
 621                 break;
 622         }
 623
 624         case MEMUNLOCK:
 625         {
 626                 struct erase_info_user einfo;
 627
 628                 if (copy_from_user(&einfo, argp, sizeof(einfo)))
 629                         return -EFAULT;
 630
 631                 if (!mtd->unlock)
 632                         ret = -EOPNOTSUPP;
 633                 else
 634                         ret = mtd->unlock(mtd, einfo.start, einfo.length);
 635                 break;
 636         }
 637
 638         /* Legacy interface */
 639         case MEMGETOOBSEL:
 640         {
 641                 struct nand_oobinfo oi;
 642
 643                 if (!mtd->ecclayout)
 644                         return -EOPNOTSUPP;
 645                 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
 646                         return -EINVAL;
 647
 648                 oi.useecc = MTD_NANDECC_AUTOPLACE;
 649                 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
 650                 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
 651                        sizeof(oi.oobfree));
 652                 oi.eccbytes = mtd->ecclayout->eccbytes;
 653
 654                 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
 655                         return -EFAULT;
 656                 break;
 657         }
 658
 659         case MEMGETBADBLOCK:
 660         {
 661                 loff_t offs;
 662
 663                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
 664                         return -EFAULT;
 665                 if (!mtd->block_isbad)
 666                         ret = -EOPNOTSUPP;
 667                 else
 668                         return mtd->block_isbad(mtd, offs);
 669                 break;
 670         }
 671
 672         case MEMSETBADBLOCK:
 673         {
 674                 loff_t offs;
 675
 676                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
 677                         return -EFAULT;
 678                 if (!mtd->block_markbad)
 679                         ret = -EOPNOTSUPP;
 680                 else
 681                         return mtd->block_markbad(mtd, offs);
 682                 break;
 683         }
 684
 685 #ifdef CONFIG_HAVE_MTD_OTP
 686         case OTPSELECT:
 687         {
 688                 int mode;
 689                 if (copy_from_user(&mode, argp, sizeof(int)))
 690                         return -EFAULT;
 691
 692                 mfi->mode = MTD_MODE_NORMAL;
 693
 694                 ret = otp_select_filemode(mfi, mode);
 695
 696                 file->f_pos = 0;
 697                 break;
 698         }
 699
 700         case OTPGETREGIONCOUNT:
 701         case OTPGETREGIONINFO:
 702         {
 703                 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
 704                 if (!buf)
 705                         return -ENOMEM;
 706                 ret = -EOPNOTSUPP;
 707                 switch (mfi->mode) {
 708                 case MTD_MODE_OTP_FACTORY:
 709                         if (mtd->get_fact_prot_info)
 710                                 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
 711                         break;
 712                 case MTD_MODE_OTP_USER:
 713                         if (mtd->get_user_prot_info)
 714                                 ret = mtd->get_user_prot_info(mtd, buf, 4096);
 715                         break;
 716                 default:
 717                         break;
 718                 }
 719                 if (ret >= 0) {
 720                         if (cmd == OTPGETREGIONCOUNT) {
 721                                 int nbr = ret / sizeof(struct otp_info);
 722                                 ret = copy_to_user(argp, &nbr, sizeof(int));
 723                         } else
 724                                 ret = copy_to_user(argp, buf, ret);
 725                         if (ret)
 726                                 ret = -EFAULT;
 727                 }
 728                 kfree(buf);
 729                 break;
 730         }
 731
 732         case OTPLOCK:
 733         {
 734                 struct otp_info oinfo;
 735
 736                 if (mfi->mode != MTD_MODE_OTP_USER)
 737                         return -EINVAL;
 738                 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
 739                         return -EFAULT;
 740                 if (!mtd->lock_user_prot_reg)
 741                         return -EOPNOTSUPP;
 742                 ret = mtd->lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
 743                 break;
 744         }
 745 #endif
 746
 747         case ECCGETLAYOUT:
 748         {
 749                 if (!mtd->ecclayout)
 750                         return -EOPNOTSUPP;
 751
 752                 if (copy_to_user(argp, mtd->ecclayout,
 753                                  sizeof(struct nand_ecclayout)))
 754                         return -EFAULT;
 755                 break;
 756         }
 757
 758         case ECCGETSTATS:
 759         {
 760                 if (copy_to_user(argp, &mtd->ecc_stats,
 761                                  sizeof(struct mtd_ecc_stats)))
 762                         return -EFAULT;
 763                 break;
 764         }
 765
 766         case MTDFILEMODE:
 767         {
 768                 mfi->mode = 0;
 769
 770                 switch(arg) {
 771                 case MTD_MODE_OTP_FACTORY:
 772                 case MTD_MODE_OTP_USER:
 773                         ret = otp_select_filemode(mfi, arg);
 774                         break;
 775
 776                 case MTD_MODE_RAW:
 777                         if (!mtd->read_oob || !mtd->write_oob)
 778                                 return -EOPNOTSUPP;
 779                         mfi->mode = arg;
 780
 781                 case MTD_MODE_NORMAL:
 782                         break;
 783                 default:
 784                         ret = -EINVAL;
 785                 }
 786                 file->f_pos = 0;
 787                 break;
 788         }
 789
 790         default:
 791                 ret = -ENOTTY;
 792         }
 793
 794         return ret;
 795 } /* memory_ioctl */
 796
 797 #ifdef CONFIG_COMPAT
 798
 799 struct mtd_oob_buf32 {
 800         u_int32_t start;
 801         u_int32_t length;
 802         compat_caddr_t ptr;     /* unsigned char* */
 803 };
 804
 805 #define MEMWRITEOOB32           _IOWR('M', 3, struct mtd_oob_buf32)
 806 #define MEMREADOOB32            _IOWR('M', 4, struct mtd_oob_buf32)
 807
 808 static long mtd_compat_ioctl(struct file *file, unsigned int cmd,
 809         unsigned long arg)
 810 {
 811         struct mtd_file_info *mfi = file->private_data;
 812         struct mtd_info *mtd = mfi->mtd;
 813         void __user *argp = (void __user *)arg;
 814         int ret = 0;
 815
 816         lock_kernel();
 817
 818         switch (cmd) {
 819         case MEMWRITEOOB32:
 820         {
 821                 struct mtd_oob_buf32 buf;
 822                 struct mtd_oob_buf32 __user *buf_user = argp;
 823
 824                 if (copy_from_user(&buf, argp, sizeof(buf)))
 825                         ret = -EFAULT;
 826                 else
 827                         ret = mtd_do_writeoob(file, mtd, buf.start,
 828                                 buf.length, compat_ptr(buf.ptr),
 829                                 &buf_user->length);
 830                 break;
 831         }
 832
 833         case MEMREADOOB32:
 834         {
 835                 struct mtd_oob_buf32 buf;
 836                 struct mtd_oob_buf32 __user *buf_user = argp;
 837
 838                 /* NOTE: writes return length to buf->start */
 839                 if (copy_from_user(&buf, argp, sizeof(buf)))
 840                         ret = -EFAULT;
 841                 else
 842                         ret = mtd_do_readoob(mtd, buf.start,
 843                                 buf.length, compat_ptr(buf.ptr),
 844                                 &buf_user->start);
 845                 break;
 846         }
 847         default:
 848                 ret = -ENOIOCTLCMD;
 849         }
 850
 851         unlock_kernel();
 852
 853         return ret;
 854 }
 855
 856 #endif /* CONFIG_COMPAT */
 857
 858 /*
 859  * try to determine where a shared mapping can be made
 860  * - only supported for NOMMU at the moment (MMU can't doesn't copy private
 861  *   mappings)
 862  */
 863 #ifndef CONFIG_MMU
 864 static unsigned long mtd_get_unmapped_area(struct file *file,
 865                                            unsigned long addr,
 866                                            unsigned long len,
 867                                            unsigned long pgoff,
 868                                            unsigned long flags)
 869 {
 870         struct mtd_file_info *mfi = file->private_data;
 871         struct mtd_info *mtd = mfi->mtd;
 872
 873         if (mtd->get_unmapped_area) {
 874                 unsigned long offset;
 875
 876                 if (addr != 0)
 877                         return (unsigned long) -EINVAL;
 878
 879                 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
 880                         return (unsigned long) -EINVAL;
 881
 882                 offset = pgoff << PAGE_SHIFT;
 883                 if (offset > mtd->size - len)
 884                         return (unsigned long) -EINVAL;
 885
 886                 return mtd->get_unmapped_area(mtd, len, offset, flags);
 887         }
 888
 889         /* can't map directly */
 890         return (unsigned long) -ENOSYS;
 891 }
 892 #endif
 893
 894 /*
 895  * set up a mapping for shared memory segments
 896  */
 897 static int mtd_mmap(struct file *file, struct vm_area_struct *vma)
 898 {
 899 #ifdef CONFIG_MMU
 900         struct mtd_file_info *mfi = file->private_data;
 901         struct mtd_info *mtd = mfi->mtd;
 902
 903         if (mtd->type == MTD_RAM || mtd->type == MTD_ROM)
 904                 return 0;
 905         return -ENOSYS;
 906 #else
 907         return vma->vm_flags & VM_SHARED ? 0 : -ENOSYS;
 908 #endif
 909 }
 910
 911 static const struct file_operations mtd_fops = {
 912         .owner          = THIS_MODULE,
 913         .llseek         = mtd_lseek,
 914         .read           = mtd_read,
 915         .write          = mtd_write,
 916         .ioctl          = mtd_ioctl,
 917 #ifdef CONFIG_COMPAT
 918         .compat_ioctl   = mtd_compat_ioctl,
 919 #endif
 920         .open           = mtd_open,
 921         .release        = mtd_close,
 922         .mmap           = mtd_mmap,
 923 #ifndef CONFIG_MMU
 924         .get_unmapped_area = mtd_get_unmapped_area,
 925 #endif
 926 };
 927
 928 static int __init init_mtdchar(void)
 929 {
 930         int status;
 931
 932         status = register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops);
 933         if (status < 0) {
 934                 printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
 935                        MTD_CHAR_MAJOR);
 936         }
 937
 938         return status;
 939 }
 940
 941 static void __exit cleanup_mtdchar(void)
 942 {
 943         unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
 944 }
 945
 946 module_init(init_mtdchar);
 947 module_exit(cleanup_mtdchar);
 948
 949 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
 950
 951 MODULE_LICENSE("GPL");
 952 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
 953 MODULE_DESCRIPTION("Direct character-device access to MTD devices");
 954 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);