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 #include <linux/mount.h>
  19
  20 #include <linux/mtd/mtd.h>
  21 #include <linux/mtd/compatmac.h>
  22
  23 #include <asm/uaccess.h>
  24
  25 #define MTD_INODE_FS_MAGIC 0x11307854
  26 static struct vfsmount *mtd_inode_mnt __read_mostly;
  27
  28 /*
  29  * Data structure to hold the pointer to the mtd device as well
  30  * as mode information ofr various use cases.
  31  */
  32 struct mtd_file_info {
  33         struct mtd_info *mtd;
  34         struct inode *ino;
  35         enum mtd_file_modes mode;
  36 };
  37
  38 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
  39 {
  40         struct mtd_file_info *mfi = file->private_data;
  41         struct mtd_info *mtd = mfi->mtd;
  42
  43         switch (orig) {
  44         case SEEK_SET:
  45                 break;
  46         case SEEK_CUR:
  47                 offset += file->f_pos;
  48                 break;
  49         case SEEK_END:
  50                 offset += mtd->size;
  51                 break;
  52         default:
  53                 return -EINVAL;
  54         }
  55
  56         if (offset >= 0 && offset <= mtd->size)
  57                 return file->f_pos = offset;
  58
  59         return -EINVAL;
  60 }
  61
  62
  63
  64 static int mtd_open(struct inode *inode, struct file *file)
  65 {
  66         int minor = iminor(inode);
  67         int devnum = minor >> 1;
  68         int ret = 0;
  69         struct mtd_info *mtd;
  70         struct mtd_file_info *mfi;
  71         struct inode *mtd_ino;
  72
  73         DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
  74
  75         /* You can't open the RO devices RW */
  76         if ((file->f_mode & FMODE_WRITE) && (minor & 1))
  77                 return -EACCES;
  78
  79         lock_kernel();
  80         mtd = get_mtd_device(NULL, devnum);
  81
  82         if (IS_ERR(mtd)) {
  83                 ret = PTR_ERR(mtd);
  84                 goto out;
  85         }
  86
  87         if (mtd->type == MTD_ABSENT) {
  88                 put_mtd_device(mtd);
  89                 ret = -ENODEV;
  90                 goto out;
  91         }
  92
  93         mtd_ino = iget_locked(mtd_inode_mnt->mnt_sb, devnum);
  94         if (!mtd_ino) {
  95                 put_mtd_device(mtd);
  96                 ret = -ENOMEM;
  97                 goto out;
  98         }
  99         if (mtd_ino->i_state & I_NEW) {
 100                 mtd_ino->i_private = mtd;
 101                 mtd_ino->i_mode = S_IFCHR;
 102                 mtd_ino->i_data.backing_dev_info = mtd->backing_dev_info;
 103                 unlock_new_inode(mtd_ino);
 104         }
 105         file->f_mapping = mtd_ino->i_mapping;
 106
 107         /* You can't open it RW if it's not a writeable device */
 108         if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
 109                 iput(mtd_ino);
 110                 put_mtd_device(mtd);
 111                 ret = -EACCES;
 112                 goto out;
 113         }
 114
 115         mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
 116         if (!mfi) {
 117                 iput(mtd_ino);
 118                 put_mtd_device(mtd);
 119                 ret = -ENOMEM;
 120                 goto out;
 121         }
 122         mfi->ino = mtd_ino;
 123         mfi->mtd = mtd;
 124         file->private_data = mfi;
 125
 126 out:
 127         unlock_kernel();
 128         return ret;
 129 } /* mtd_open */
 130
 131 /*====================================================================*/
 132
 133 static int mtd_close(struct inode *inode, struct file *file)
 134 {
 135         struct mtd_file_info *mfi = file->private_data;
 136         struct mtd_info *mtd = mfi->mtd;
 137
 138         DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
 139
 140         /* Only sync if opened RW */
 141         if ((file->f_mode & FMODE_WRITE) && mtd->sync)
 142                 mtd->sync(mtd);
 143
 144         iput(mfi->ino);
 145
 146         put_mtd_device(mtd);
 147         file->private_data = NULL;
 148         kfree(mfi);
 149
 150         return 0;
 151 } /* mtd_close */
 152
 153 /* FIXME: This _really_ needs to die. In 2.5, we should lock the
 154    userspace buffer down and use it directly with readv/writev.
 155 */
 156 #define MAX_KMALLOC_SIZE 0x20000
 157
 158 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
 159 {
 160         struct mtd_file_info *mfi = file->private_data;
 161         struct mtd_info *mtd = mfi->mtd;
 162         size_t retlen=0;
 163         size_t total_retlen=0;
 164         int ret=0;
 165         int len;
 166         char *kbuf;
 167
 168         DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
 169
 170         if (*ppos + count > mtd->size)
 171                 count = mtd->size - *ppos;
 172
 173         if (!count)
 174                 return 0;
 175
 176         /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
 177            and pass them directly to the MTD functions */
 178
 179         if (count > MAX_KMALLOC_SIZE)
 180                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
 181         else
 182                 kbuf=kmalloc(count, GFP_KERNEL);
 183
 184         if (!kbuf)
 185                 return -ENOMEM;
 186
 187         while (count) {
 188
 189                 if (count > MAX_KMALLOC_SIZE)
 190                         len = MAX_KMALLOC_SIZE;
 191                 else
 192                         len = count;
 193
 194                 switch (mfi->mode) {
 195                 case MTD_MODE_OTP_FACTORY:
 196                         ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 197                         break;
 198                 case MTD_MODE_OTP_USER:
 199                         ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 200                         break;
 201                 case MTD_MODE_RAW:
 202                 {
 203                         struct mtd_oob_ops ops;
 204
 205                         ops.mode = MTD_OOB_RAW;
 206                         ops.datbuf = kbuf;
 207                         ops.oobbuf = NULL;
 208                         ops.len = len;
 209
 210                         ret = mtd->read_oob(mtd, *ppos, &ops);
 211                         retlen = ops.retlen;
 212                         break;
 213                 }
 214                 default:
 215                         ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
 216                 }
 217                 /* Nand returns -EBADMSG on ecc errors, but it returns
 218                  * the data. For our userspace tools it is important
 219                  * to dump areas with ecc errors !
 220                  * For kernel internal usage it also might return -EUCLEAN
 221                  * to signal the caller that a bitflip has occured and has
 222                  * been corrected by the ECC algorithm.
 223                  * Userspace software which accesses NAND this way
 224                  * must be aware of the fact that it deals with NAND
 225                  */
 226                 if (!ret || (ret == -EUCLEAN) || (ret == -EBADMSG)) {
 227                         *ppos += retlen;
 228                         if (copy_to_user(buf, kbuf, retlen)) {
 229                                 kfree(kbuf);
 230                                 return -EFAULT;
 231                         }
 232                         else
 233                                 total_retlen += retlen;
 234
 235                         count -= retlen;
 236                         buf += retlen;
 237                         if (retlen == 0)
 238                                 count = 0;
 239                 }
 240                 else {
 241                         kfree(kbuf);
 242                         return ret;
 243                 }
 244
 245         }
 246
 247         kfree(kbuf);
 248         return total_retlen;
 249 } /* mtd_read */
 250
 251 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
 252 {
 253         struct mtd_file_info *mfi = file->private_data;
 254         struct mtd_info *mtd = mfi->mtd;
 255         char *kbuf;
 256         size_t retlen;
 257         size_t total_retlen=0;
 258         int ret=0;
 259         int len;
 260
 261         DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
 262
 263         if (*ppos == mtd->size)
 264                 return -ENOSPC;
 265
 266         if (*ppos + count > mtd->size)
 267                 count = mtd->size - *ppos;
 268
 269         if (!count)
 270                 return 0;
 271
 272         if (count > MAX_KMALLOC_SIZE)
 273                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
 274         else
 275                 kbuf=kmalloc(count, GFP_KERNEL);
 276
 277         if (!kbuf)
 278                 return -ENOMEM;
 279
 280         while (count) {
 281
 282                 if (count > MAX_KMALLOC_SIZE)
 283                         len = MAX_KMALLOC_SIZE;
 284                 else
 285                         len = count;
 286
 287                 if (copy_from_user(kbuf, buf, len)) {
 288                         kfree(kbuf);
 289                         return -EFAULT;
 290                 }
 291
 292                 switch (mfi->mode) {
 293                 case MTD_MODE_OTP_FACTORY:
 294                         ret = -EROFS;
 295                         break;
 296                 case MTD_MODE_OTP_USER:
 297                         if (!mtd->write_user_prot_reg) {
 298                                 ret = -EOPNOTSUPP;
 299                                 break;
 300                         }
 301                         ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 302                         break;
 303
 304                 case MTD_MODE_RAW:
 305                 {
 306                         struct mtd_oob_ops ops;
 307
 308                         ops.mode = MTD_OOB_RAW;
 309                         ops.datbuf = kbuf;
 310                         ops.oobbuf = NULL;
 311                         ops.len = len;
 312
 313                         ret = mtd->write_oob(mtd, *ppos, &ops);
 314                         retlen = ops.retlen;
 315                         break;
 316                 }
 317
 318                 default:
 319                         ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
 320                 }
 321                 if (!ret) {
 322                         *ppos += retlen;
 323                         total_retlen += retlen;
 324                         count -= retlen;
 325                         buf += retlen;
 326                 }
 327                 else {
 328                         kfree(kbuf);
 329                         return ret;
 330                 }
 331         }
 332
 333         kfree(kbuf);
 334         return total_retlen;
 335 } /* mtd_write */
 336
 337 /*======================================================================
 338
 339     IOCTL calls for getting device parameters.
 340
 341 ======================================================================*/
 342 static void mtdchar_erase_callback (struct erase_info *instr)
 343 {
 344         wake_up((wait_queue_head_t *)instr->priv);
 345 }
 346
 347 #ifdef CONFIG_HAVE_MTD_OTP
 348 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
 349 {
 350         struct mtd_info *mtd = mfi->mtd;
 351         int ret = 0;
 352
 353         switch (mode) {
 354         case MTD_OTP_FACTORY:
 355                 if (!mtd->read_fact_prot_reg)
 356                         ret = -EOPNOTSUPP;
 357                 else
 358                         mfi->mode = MTD_MODE_OTP_FACTORY;
 359                 break;
 360         case MTD_OTP_USER:
 361                 if (!mtd->read_fact_prot_reg)
 362                         ret = -EOPNOTSUPP;
 363                 else
 364                         mfi->mode = MTD_MODE_OTP_USER;
 365                 break;
 366         default:
 367                 ret = -EINVAL;
 368         case MTD_OTP_OFF:
 369                 break;
 370         }
 371         return ret;
 372 }
 373 #else
 374 # define otp_select_filemode(f,m)       -EOPNOTSUPP
 375 #endif
 376
 377 static int mtd_do_writeoob(struct file *file, struct mtd_info *mtd,
 378         uint64_t start, uint32_t length, void __user *ptr,
 379         uint32_t __user *retp)
 380 {
 381         struct mtd_oob_ops ops;
 382         uint32_t retlen;
 383         int ret = 0;
 384
 385         if (!(file->f_mode & FMODE_WRITE))
 386                 return -EPERM;
 387
 388         if (length > 4096)
 389                 return -EINVAL;
 390
 391         if (!mtd->write_oob)
 392                 ret = -EOPNOTSUPP;
 393         else
 394                 ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
 395
 396         if (ret)
 397                 return ret;
 398
 399         ops.ooblen = length;
 400         ops.ooboffs = start & (mtd->oobsize - 1);
 401         ops.datbuf = NULL;
 402         ops.mode = MTD_OOB_PLACE;
 403
 404         if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
 405                 return -EINVAL;
 406
 407         ops.oobbuf = kmalloc(length, GFP_KERNEL);
 408         if (!ops.oobbuf)
 409                 return -ENOMEM;
 410
 411         if (copy_from_user(ops.oobbuf, ptr, length)) {
 412                 kfree(ops.oobbuf);
 413                 return -EFAULT;
 414         }
 415
 416         start &= ~((uint64_t)mtd->oobsize - 1);
 417         ret = mtd->write_oob(mtd, start, &ops);
 418
 419         if (ops.oobretlen > 0xFFFFFFFFU)
 420                 ret = -EOVERFLOW;
 421         retlen = ops.oobretlen;
 422         if (copy_to_user(retp, &retlen, sizeof(length)))
 423                 ret = -EFAULT;
 424
 425         kfree(ops.oobbuf);
 426         return ret;
 427 }
 428
 429 static int mtd_do_readoob(struct mtd_info *mtd, uint64_t start,
 430         uint32_t length, void __user *ptr, uint32_t __user *retp)
 431 {
 432         struct mtd_oob_ops ops;
 433         int ret = 0;
 434
 435         if (length > 4096)
 436                 return -EINVAL;
 437
 438         if (!mtd->read_oob)
 439                 ret = -EOPNOTSUPP;
 440         else
 441                 ret = access_ok(VERIFY_WRITE, ptr,
 442                                 length) ? 0 : -EFAULT;
 443         if (ret)
 444                 return ret;
 445
 446         ops.ooblen = length;
 447         ops.ooboffs = start & (mtd->oobsize - 1);
 448         ops.datbuf = NULL;
 449         ops.mode = MTD_OOB_PLACE;
 450
 451         if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
 452                 return -EINVAL;
 453
 454         ops.oobbuf = kmalloc(length, GFP_KERNEL);
 455         if (!ops.oobbuf)
 456                 return -ENOMEM;
 457
 458         start &= ~((uint64_t)mtd->oobsize - 1);
 459         ret = mtd->read_oob(mtd, start, &ops);
 460
 461         if (put_user(ops.oobretlen, retp))
 462                 ret = -EFAULT;
 463         else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
 464                                             ops.oobretlen))
 465                 ret = -EFAULT;
 466
 467         kfree(ops.oobbuf);
 468         return ret;
 469 }
 470
 471 static int mtd_ioctl(struct inode *inode, struct file *file,
 472                      u_int cmd, u_long arg)
 473 {
 474         struct mtd_file_info *mfi = file->private_data;
 475         struct mtd_info *mtd = mfi->mtd;
 476         void __user *argp = (void __user *)arg;
 477         int ret = 0;
 478         u_long size;
 479         struct mtd_info_user info;
 480
 481         DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
 482
 483         size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
 484         if (cmd & IOC_IN) {
 485                 if (!access_ok(VERIFY_READ, argp, size))
 486                         return -EFAULT;
 487         }
 488         if (cmd & IOC_OUT) {
 489                 if (!access_ok(VERIFY_WRITE, argp, size))
 490                         return -EFAULT;
 491         }
 492
 493         switch (cmd) {
 494         case MEMGETREGIONCOUNT:
 495                 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
 496                         return -EFAULT;
 497                 break;
 498
 499         case MEMGETREGIONINFO:
 500         {
 501                 uint32_t ur_idx;
 502                 struct mtd_erase_region_info *kr;
 503                 struct region_info_user __user *ur = argp;
 504
 505                 if (get_user(ur_idx, &(ur->regionindex)))
 506                         return -EFAULT;
 507
 508                 kr = &(mtd->eraseregions[ur_idx]);
 509
 510                 if (put_user(kr->offset, &(ur->offset))
 511                     || put_user(kr->erasesize, &(ur->erasesize))
 512                     || put_user(kr->numblocks, &(ur->numblocks)))
 513                         return -EFAULT;
 514
 515                 break;
 516         }
 517
 518         case MEMGETINFO:
 519                 info.type       = mtd->type;
 520                 info.flags      = mtd->flags;
 521                 info.size       = mtd->size;
 522                 info.erasesize  = mtd->erasesize;
 523                 info.writesize  = mtd->writesize;
 524                 info.oobsize    = mtd->oobsize;
 525                 /* The below fields are obsolete */
 526                 info.ecctype    = -1;
 527                 info.eccsize    = 0;
 528                 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
 529                         return -EFAULT;
 530                 break;
 531
 532         case MEMERASE:
 533         case MEMERASE64:
 534         {
 535                 struct erase_info *erase;
 536
 537                 if(!(file->f_mode & FMODE_WRITE))
 538                         return -EPERM;
 539
 540                 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
 541                 if (!erase)
 542                         ret = -ENOMEM;
 543                 else {
 544                         wait_queue_head_t waitq;
 545                         DECLARE_WAITQUEUE(wait, current);
 546
 547                         init_waitqueue_head(&waitq);
 548
 549                         if (cmd == MEMERASE64) {
 550                                 struct erase_info_user64 einfo64;
 551
 552                                 if (copy_from_user(&einfo64, argp,
 553                                             sizeof(struct erase_info_user64))) {
 554                                         kfree(erase);
 555                                         return -EFAULT;
 556                                 }
 557                                 erase->addr = einfo64.start;
 558                                 erase->len = einfo64.length;
 559                         } else {
 560                                 struct erase_info_user einfo32;
 561
 562                                 if (copy_from_user(&einfo32, argp,
 563                                             sizeof(struct erase_info_user))) {
 564                                         kfree(erase);
 565                                         return -EFAULT;
 566                                 }
 567                                 erase->addr = einfo32.start;
 568                                 erase->len = einfo32.length;
 569                         }
 570                         erase->mtd = mtd;
 571                         erase->callback = mtdchar_erase_callback;
 572                         erase->priv = (unsigned long)&waitq;
 573
 574                         /*
 575                           FIXME: Allow INTERRUPTIBLE. Which means
 576                           not having the wait_queue head on the stack.
 577
 578                           If the wq_head is on the stack, and we
 579                           leave because we got interrupted, then the
 580                           wq_head is no longer there when the
 581                           callback routine tries to wake us up.
 582                         */
 583                         ret = mtd->erase(mtd, erase);
 584                         if (!ret) {
 585                                 set_current_state(TASK_UNINTERRUPTIBLE);
 586                                 add_wait_queue(&waitq, &wait);
 587                                 if (erase->state != MTD_ERASE_DONE &&
 588                                     erase->state != MTD_ERASE_FAILED)
 589                                         schedule();
 590                                 remove_wait_queue(&waitq, &wait);
 591                                 set_current_state(TASK_RUNNING);
 592
 593                                 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
 594                         }
 595                         kfree(erase);
 596                 }
 597                 break;
 598         }
 599
 600         case MEMWRITEOOB:
 601         {
 602                 struct mtd_oob_buf buf;
 603                 struct mtd_oob_buf __user *buf_user = argp;
 604
 605                 /* NOTE: writes return length to buf_user->length */
 606                 if (copy_from_user(&buf, argp, sizeof(buf)))
 607                         ret = -EFAULT;
 608                 else
 609                         ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
 610                                 buf.ptr, &buf_user->length);
 611                 break;
 612         }
 613
 614         case MEMREADOOB:
 615         {
 616                 struct mtd_oob_buf buf;
 617                 struct mtd_oob_buf __user *buf_user = argp;
 618
 619                 /* NOTE: writes return length to buf_user->start */
 620                 if (copy_from_user(&buf, argp, sizeof(buf)))
 621                         ret = -EFAULT;
 622                 else
 623                         ret = mtd_do_readoob(mtd, buf.start, buf.length,
 624                                 buf.ptr, &buf_user->start);
 625                 break;
 626         }
 627
 628         case MEMWRITEOOB64:
 629         {
 630                 struct mtd_oob_buf64 buf;
 631                 struct mtd_oob_buf64 __user *buf_user = argp;
 632
 633                 if (copy_from_user(&buf, argp, sizeof(buf)))
 634                         ret = -EFAULT;
 635                 else
 636                         ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
 637                                 (void __user *)(uintptr_t)buf.usr_ptr,
 638                                 &buf_user->length);
 639                 break;
 640         }
 641
 642         case MEMREADOOB64:
 643         {
 644                 struct mtd_oob_buf64 buf;
 645                 struct mtd_oob_buf64 __user *buf_user = argp;
 646
 647                 if (copy_from_user(&buf, argp, sizeof(buf)))
 648                         ret = -EFAULT;
 649                 else
 650                         ret = mtd_do_readoob(mtd, buf.start, buf.length,
 651                                 (void __user *)(uintptr_t)buf.usr_ptr,
 652                                 &buf_user->length);
 653                 break;
 654         }
 655
 656         case MEMLOCK:
 657         {
 658                 struct erase_info_user einfo;
 659
 660                 if (copy_from_user(&einfo, argp, sizeof(einfo)))
 661                         return -EFAULT;
 662
 663                 if (!mtd->lock)
 664                         ret = -EOPNOTSUPP;
 665                 else
 666                         ret = mtd->lock(mtd, einfo.start, einfo.length);
 667                 break;
 668         }
 669
 670         case MEMUNLOCK:
 671         {
 672                 struct erase_info_user einfo;
 673
 674                 if (copy_from_user(&einfo, argp, sizeof(einfo)))
 675                         return -EFAULT;
 676
 677                 if (!mtd->unlock)
 678                         ret = -EOPNOTSUPP;
 679                 else
 680                         ret = mtd->unlock(mtd, einfo.start, einfo.length);
 681                 break;
 682         }
 683
 684         /* Legacy interface */
 685         case MEMGETOOBSEL:
 686         {
 687                 struct nand_oobinfo oi;
 688
 689                 if (!mtd->ecclayout)
 690                         return -EOPNOTSUPP;
 691                 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
 692                         return -EINVAL;
 693
 694                 oi.useecc = MTD_NANDECC_AUTOPLACE;
 695                 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
 696                 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
 697                        sizeof(oi.oobfree));
 698                 oi.eccbytes = mtd->ecclayout->eccbytes;
 699
 700                 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
 701                         return -EFAULT;
 702                 break;
 703         }
 704
 705         case MEMGETBADBLOCK:
 706         {
 707                 loff_t offs;
 708
 709                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
 710                         return -EFAULT;
 711                 if (!mtd->block_isbad)
 712                         ret = -EOPNOTSUPP;
 713                 else
 714                         return mtd->block_isbad(mtd, offs);
 715                 break;
 716         }
 717
 718         case MEMSETBADBLOCK:
 719         {
 720                 loff_t offs;
 721
 722                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
 723                         return -EFAULT;
 724                 if (!mtd->block_markbad)
 725                         ret = -EOPNOTSUPP;
 726                 else
 727                         return mtd->block_markbad(mtd, offs);
 728                 break;
 729         }
 730
 731 #ifdef CONFIG_HAVE_MTD_OTP
 732         case OTPSELECT:
 733         {
 734                 int mode;
 735                 if (copy_from_user(&mode, argp, sizeof(int)))
 736                         return -EFAULT;
 737
 738                 mfi->mode = MTD_MODE_NORMAL;
 739
 740                 ret = otp_select_filemode(mfi, mode);
 741
 742                 file->f_pos = 0;
 743                 break;
 744         }
 745
 746         case OTPGETREGIONCOUNT:
 747         case OTPGETREGIONINFO:
 748         {
 749                 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
 750                 if (!buf)
 751                         return -ENOMEM;
 752                 ret = -EOPNOTSUPP;
 753                 switch (mfi->mode) {
 754                 case MTD_MODE_OTP_FACTORY:
 755                         if (mtd->get_fact_prot_info)
 756                                 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
 757                         break;
 758                 case MTD_MODE_OTP_USER:
 759                         if (mtd->get_user_prot_info)
 760                                 ret = mtd->get_user_prot_info(mtd, buf, 4096);
 761                         break;
 762                 default:
 763                         break;
 764                 }
 765                 if (ret >= 0) {
 766                         if (cmd == OTPGETREGIONCOUNT) {
 767                                 int nbr = ret / sizeof(struct otp_info);
 768                                 ret = copy_to_user(argp, &nbr, sizeof(int));
 769                         } else
 770                                 ret = copy_to_user(argp, buf, ret);
 771                         if (ret)
 772                                 ret = -EFAULT;
 773                 }
 774                 kfree(buf);
 775                 break;
 776         }
 777
 778         case OTPLOCK:
 779         {
 780                 struct otp_info oinfo;
 781
 782                 if (mfi->mode != MTD_MODE_OTP_USER)
 783                         return -EINVAL;
 784                 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
 785                         return -EFAULT;
 786                 if (!mtd->lock_user_prot_reg)
 787                         return -EOPNOTSUPP;
 788                 ret = mtd->lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
 789                 break;
 790         }
 791 #endif
 792
 793         case ECCGETLAYOUT:
 794         {
 795                 if (!mtd->ecclayout)
 796                         return -EOPNOTSUPP;
 797
 798                 if (copy_to_user(argp, mtd->ecclayout,
 799                                  sizeof(struct nand_ecclayout)))
 800                         return -EFAULT;
 801                 break;
 802         }
 803
 804         case ECCGETSTATS:
 805         {
 806                 if (copy_to_user(argp, &mtd->ecc_stats,
 807                                  sizeof(struct mtd_ecc_stats)))
 808                         return -EFAULT;
 809                 break;
 810         }
 811
 812         case MTDFILEMODE:
 813         {
 814                 mfi->mode = 0;
 815
 816                 switch(arg) {
 817                 case MTD_MODE_OTP_FACTORY:
 818                 case MTD_MODE_OTP_USER:
 819                         ret = otp_select_filemode(mfi, arg);
 820                         break;
 821
 822                 case MTD_MODE_RAW:
 823                         if (!mtd->read_oob || !mtd->write_oob)
 824                                 return -EOPNOTSUPP;
 825                         mfi->mode = arg;
 826
 827                 case MTD_MODE_NORMAL:
 828                         break;
 829                 default:
 830                         ret = -EINVAL;
 831                 }
 832                 file->f_pos = 0;
 833                 break;
 834         }
 835
 836         default:
 837                 ret = -ENOTTY;
 838         }
 839
 840         return ret;
 841 } /* memory_ioctl */
 842
 843 #ifdef CONFIG_COMPAT
 844
 845 struct mtd_oob_buf32 {
 846         u_int32_t start;
 847         u_int32_t length;
 848         compat_caddr_t ptr;     /* unsigned char* */
 849 };
 850
 851 #define MEMWRITEOOB32           _IOWR('M', 3, struct mtd_oob_buf32)
 852 #define MEMREADOOB32            _IOWR('M', 4, struct mtd_oob_buf32)
 853
 854 static long mtd_compat_ioctl(struct file *file, unsigned int cmd,
 855         unsigned long arg)
 856 {
 857         struct inode *inode = file->f_path.dentry->d_inode;
 858         struct mtd_file_info *mfi = file->private_data;
 859         struct mtd_info *mtd = mfi->mtd;
 860         void __user *argp = compat_ptr(arg);
 861         int ret = 0;
 862
 863         lock_kernel();
 864
 865         switch (cmd) {
 866         case MEMWRITEOOB32:
 867         {
 868                 struct mtd_oob_buf32 buf;
 869                 struct mtd_oob_buf32 __user *buf_user = argp;
 870
 871                 if (copy_from_user(&buf, argp, sizeof(buf)))
 872                         ret = -EFAULT;
 873                 else
 874                         ret = mtd_do_writeoob(file, mtd, buf.start,
 875                                 buf.length, compat_ptr(buf.ptr),
 876                                 &buf_user->length);
 877                 break;
 878         }
 879
 880         case MEMREADOOB32:
 881         {
 882                 struct mtd_oob_buf32 buf;
 883                 struct mtd_oob_buf32 __user *buf_user = argp;
 884
 885                 /* NOTE: writes return length to buf->start */
 886                 if (copy_from_user(&buf, argp, sizeof(buf)))
 887                         ret = -EFAULT;
 888                 else
 889                         ret = mtd_do_readoob(mtd, buf.start,
 890                                 buf.length, compat_ptr(buf.ptr),
 891                                 &buf_user->start);
 892                 break;
 893         }
 894         default:
 895                 ret = mtd_ioctl(inode, file, cmd, (unsigned long)argp);
 896         }
 897
 898         unlock_kernel();
 899
 900         return ret;
 901 }
 902
 903 #endif /* CONFIG_COMPAT */
 904
 905 /*
 906  * try to determine where a shared mapping can be made
 907  * - only supported for NOMMU at the moment (MMU can't doesn't copy private
 908  *   mappings)
 909  */
 910 #ifndef CONFIG_MMU
 911 static unsigned long mtd_get_unmapped_area(struct file *file,
 912                                            unsigned long addr,
 913                                            unsigned long len,
 914                                            unsigned long pgoff,
 915                                            unsigned long flags)
 916 {
 917         struct mtd_file_info *mfi = file->private_data;
 918         struct mtd_info *mtd = mfi->mtd;
 919
 920         if (mtd->get_unmapped_area) {
 921                 unsigned long offset;
 922
 923                 if (addr != 0)
 924                         return (unsigned long) -EINVAL;
 925
 926                 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
 927                         return (unsigned long) -EINVAL;
 928
 929                 offset = pgoff << PAGE_SHIFT;
 930                 if (offset > mtd->size - len)
 931                         return (unsigned long) -EINVAL;
 932
 933                 return mtd->get_unmapped_area(mtd, len, offset, flags);
 934         }
 935
 936         /* can't map directly */
 937         return (unsigned long) -ENOSYS;
 938 }
 939 #endif
 940
 941 /*
 942  * set up a mapping for shared memory segments
 943  */
 944 static int mtd_mmap(struct file *file, struct vm_area_struct *vma)
 945 {
 946 #ifdef CONFIG_MMU
 947         struct mtd_file_info *mfi = file->private_data;
 948         struct mtd_info *mtd = mfi->mtd;
 949
 950         if (mtd->type == MTD_RAM || mtd->type == MTD_ROM)
 951                 return 0;
 952         return -ENOSYS;
 953 #else
 954         return vma->vm_flags & VM_SHARED ? 0 : -ENOSYS;
 955 #endif
 956 }
 957
 958 static const struct file_operations mtd_fops = {
 959         .owner          = THIS_MODULE,
 960         .llseek         = mtd_lseek,
 961         .read           = mtd_read,
 962         .write          = mtd_write,
 963         .ioctl          = mtd_ioctl,
 964 #ifdef CONFIG_COMPAT
 965         .compat_ioctl   = mtd_compat_ioctl,
 966 #endif
 967         .open           = mtd_open,
 968         .release        = mtd_close,
 969         .mmap           = mtd_mmap,
 970 #ifndef CONFIG_MMU
 971         .get_unmapped_area = mtd_get_unmapped_area,
 972 #endif
 973 };
 974
 975 static int mtd_inodefs_get_sb(struct file_system_type *fs_type, int flags,
 976                                const char *dev_name, void *data,
 977                                struct vfsmount *mnt)
 978 {
 979         return get_sb_pseudo(fs_type, "mtd_inode:", NULL, MTD_INODE_FS_MAGIC,
 980                              mnt);
 981 }
 982
 983 static struct file_system_type mtd_inodefs_type = {
 984        .name = "mtd_inodefs",
 985        .get_sb = mtd_inodefs_get_sb,
 986        .kill_sb = kill_anon_super,
 987 };
 988
 989 static void mtdchar_notify_add(struct mtd_info *mtd)
 990 {
 991 }
 992
 993 static void mtdchar_notify_remove(struct mtd_info *mtd)
 994 {
 995         struct inode *mtd_ino = ilookup(mtd_inode_mnt->mnt_sb, mtd->index);
 996
 997         if (mtd_ino) {
 998                 /* Destroy the inode if it exists */
 999                 mtd_ino->i_nlink = 0;
1000                 iput(mtd_ino);
1001         }
1002 }
1003
1004 static struct mtd_notifier mtdchar_notifier = {
1005         .add = mtdchar_notify_add,
1006         .remove = mtdchar_notify_remove,
1007 };
1008
1009 static int __init init_mtdchar(void)
1010 {
1011         int ret;
1012
1013         ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1014                                    "mtd", &mtd_fops);
1015         if (ret < 0) {
1016                 pr_notice("Can't allocate major number %d for "
1017                                 "Memory Technology Devices.\n", MTD_CHAR_MAJOR);
1018                 return ret;
1019         }
1020
1021         ret = register_filesystem(&mtd_inodefs_type);
1022         if (ret) {
1023                 pr_notice("Can't register mtd_inodefs filesystem: %d\n", ret);
1024                 goto err_unregister_chdev;
1025         }
1026
1027         mtd_inode_mnt = kern_mount(&mtd_inodefs_type);
1028         if (IS_ERR(mtd_inode_mnt)) {
1029                 ret = PTR_ERR(mtd_inode_mnt);
1030                 pr_notice("Error mounting mtd_inodefs filesystem: %d\n", ret);
1031                 goto err_unregister_filesystem;
1032         }
1033         register_mtd_user(&mtdchar_notifier);
1034
1035         return ret;
1036
1037 err_unregister_filesystem:
1038         unregister_filesystem(&mtd_inodefs_type);
1039 err_unregister_chdev:
1040         __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1041         return ret;
1042 }
1043
1044 static void __exit cleanup_mtdchar(void)
1045 {
1046         unregister_mtd_user(&mtdchar_notifier);
1047         mntput(mtd_inode_mnt);
1048         unregister_filesystem(&mtd_inodefs_type);
1049         __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1050 }
1051
1052 module_init(init_mtdchar);
1053 module_exit(cleanup_mtdchar);
1054
1055 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
1056
1057 MODULE_LICENSE("GPL");
1058 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1059 MODULE_DESCRIPTION("Direct character-device access to MTD devices");
1060 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);