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/map.h>
  22 #include <linux/mtd/compatmac.h>
  23
  24 #include <asm/uaccess.h>
  25
  26 #define MTD_INODE_FS_MAGIC 0x11307854
  27 static struct vfsmount *mtd_inode_mnt __read_mostly;
  28
  29 /*
  30  * Data structure to hold the pointer to the mtd device as well
  31  * as mode information ofr various use cases.
  32  */
  33 struct mtd_file_info {
  34         struct mtd_info *mtd;
  35         struct inode *ino;
  36         enum mtd_file_modes mode;
  37 };
  38
  39 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
  40 {
  41         struct mtd_file_info *mfi = file->private_data;
  42         struct mtd_info *mtd = mfi->mtd;
  43
  44         switch (orig) {
  45         case SEEK_SET:
  46                 break;
  47         case SEEK_CUR:
  48                 offset += file->f_pos;
  49                 break;
  50         case SEEK_END:
  51                 offset += mtd->size;
  52                 break;
  53         default:
  54                 return -EINVAL;
  55         }
  56
  57         if (offset >= 0 && offset <= mtd->size)
  58                 return file->f_pos = offset;
  59
  60         return -EINVAL;
  61 }
  62
  63
  64
  65 static int mtd_open(struct inode *inode, struct file *file)
  66 {
  67         int minor = iminor(inode);
  68         int devnum = minor >> 1;
  69         int ret = 0;
  70         struct mtd_info *mtd;
  71         struct mtd_file_info *mfi;
  72         struct inode *mtd_ino;
  73
  74         DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
  75
  76         /* You can't open the RO devices RW */
  77         if ((file->f_mode & FMODE_WRITE) && (minor & 1))
  78                 return -EACCES;
  79
  80         lock_kernel();
  81         mtd = get_mtd_device(NULL, devnum);
  82
  83         if (IS_ERR(mtd)) {
  84                 ret = PTR_ERR(mtd);
  85                 goto out;
  86         }
  87
  88         if (mtd->type == MTD_ABSENT) {
  89                 put_mtd_device(mtd);
  90                 ret = -ENODEV;
  91                 goto out;
  92         }
  93
  94         mtd_ino = iget_locked(mtd_inode_mnt->mnt_sb, devnum);
  95         if (!mtd_ino) {
  96                 put_mtd_device(mtd);
  97                 ret = -ENOMEM;
  98                 goto out;
  99         }
 100         if (mtd_ino->i_state & I_NEW) {
 101                 mtd_ino->i_private = mtd;
 102                 mtd_ino->i_mode = S_IFCHR;
 103                 mtd_ino->i_data.backing_dev_info = mtd->backing_dev_info;
 104                 unlock_new_inode(mtd_ino);
 105         }
 106         file->f_mapping = mtd_ino->i_mapping;
 107
 108         /* You can't open it RW if it's not a writeable device */
 109         if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
 110                 iput(mtd_ino);
 111                 put_mtd_device(mtd);
 112                 ret = -EACCES;
 113                 goto out;
 114         }
 115
 116         mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
 117         if (!mfi) {
 118                 iput(mtd_ino);
 119                 put_mtd_device(mtd);
 120                 ret = -ENOMEM;
 121                 goto out;
 122         }
 123         mfi->ino = mtd_ino;
 124         mfi->mtd = mtd;
 125         file->private_data = mfi;
 126
 127 out:
 128         unlock_kernel();
 129         return ret;
 130 } /* mtd_open */
 131
 132 /*====================================================================*/
 133
 134 static int mtd_close(struct inode *inode, struct file *file)
 135 {
 136         struct mtd_file_info *mfi = file->private_data;
 137         struct mtd_info *mtd = mfi->mtd;
 138
 139         DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
 140
 141         /* Only sync if opened RW */
 142         if ((file->f_mode & FMODE_WRITE) && mtd->sync)
 143                 mtd->sync(mtd);
 144
 145         iput(mfi->ino);
 146
 147         put_mtd_device(mtd);
 148         file->private_data = NULL;
 149         kfree(mfi);
 150
 151         return 0;
 152 } /* mtd_close */
 153
 154 /* FIXME: This _really_ needs to die. In 2.5, we should lock the
 155    userspace buffer down and use it directly with readv/writev.
 156 */
 157 #define MAX_KMALLOC_SIZE 0x20000
 158
 159 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
 160 {
 161         struct mtd_file_info *mfi = file->private_data;
 162         struct mtd_info *mtd = mfi->mtd;
 163         size_t retlen=0;
 164         size_t total_retlen=0;
 165         int ret=0;
 166         int len;
 167         char *kbuf;
 168
 169         DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
 170
 171         if (*ppos + count > mtd->size)
 172                 count = mtd->size - *ppos;
 173
 174         if (!count)
 175                 return 0;
 176
 177         /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
 178            and pass them directly to the MTD functions */
 179
 180         if (count > MAX_KMALLOC_SIZE)
 181                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
 182         else
 183                 kbuf=kmalloc(count, GFP_KERNEL);
 184
 185         if (!kbuf)
 186                 return -ENOMEM;
 187
 188         while (count) {
 189
 190                 if (count > MAX_KMALLOC_SIZE)
 191                         len = MAX_KMALLOC_SIZE;
 192                 else
 193                         len = count;
 194
 195                 switch (mfi->mode) {
 196                 case MTD_MODE_OTP_FACTORY:
 197                         ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 198                         break;
 199                 case MTD_MODE_OTP_USER:
 200                         ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 201                         break;
 202                 case MTD_MODE_RAW:
 203                 {
 204                         struct mtd_oob_ops ops;
 205
 206                         ops.mode = MTD_OOB_RAW;
 207                         ops.datbuf = kbuf;
 208                         ops.oobbuf = NULL;
 209                         ops.len = len;
 210
 211                         ret = mtd->read_oob(mtd, *ppos, &ops);
 212                         retlen = ops.retlen;
 213                         break;
 214                 }
 215                 default:
 216                         ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
 217                 }
 218                 /* Nand returns -EBADMSG on ecc errors, but it returns
 219                  * the data. For our userspace tools it is important
 220                  * to dump areas with ecc errors !
 221                  * For kernel internal usage it also might return -EUCLEAN
 222                  * to signal the caller that a bitflip has occured and has
 223                  * been corrected by the ECC algorithm.
 224                  * Userspace software which accesses NAND this way
 225                  * must be aware of the fact that it deals with NAND
 226                  */
 227                 if (!ret || (ret == -EUCLEAN) || (ret == -EBADMSG)) {
 228                         *ppos += retlen;
 229                         if (copy_to_user(buf, kbuf, retlen)) {
 230                                 kfree(kbuf);
 231                                 return -EFAULT;
 232                         }
 233                         else
 234                                 total_retlen += retlen;
 235
 236                         count -= retlen;
 237                         buf += retlen;
 238                         if (retlen == 0)
 239                                 count = 0;
 240                 }
 241                 else {
 242                         kfree(kbuf);
 243                         return ret;
 244                 }
 245
 246         }
 247
 248         kfree(kbuf);
 249         return total_retlen;
 250 } /* mtd_read */
 251
 252 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
 253 {
 254         struct mtd_file_info *mfi = file->private_data;
 255         struct mtd_info *mtd = mfi->mtd;
 256         char *kbuf;
 257         size_t retlen;
 258         size_t total_retlen=0;
 259         int ret=0;
 260         int len;
 261
 262         DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
 263
 264         if (*ppos == mtd->size)
 265                 return -ENOSPC;
 266
 267         if (*ppos + count > mtd->size)
 268                 count = mtd->size - *ppos;
 269
 270         if (!count)
 271                 return 0;
 272
 273         if (count > MAX_KMALLOC_SIZE)
 274                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
 275         else
 276                 kbuf=kmalloc(count, GFP_KERNEL);
 277
 278         if (!kbuf)
 279                 return -ENOMEM;
 280
 281         while (count) {
 282
 283                 if (count > MAX_KMALLOC_SIZE)
 284                         len = MAX_KMALLOC_SIZE;
 285                 else
 286                         len = count;
 287
 288                 if (copy_from_user(kbuf, buf, len)) {
 289                         kfree(kbuf);
 290                         return -EFAULT;
 291                 }
 292
 293                 switch (mfi->mode) {
 294                 case MTD_MODE_OTP_FACTORY:
 295                         ret = -EROFS;
 296                         break;
 297                 case MTD_MODE_OTP_USER:
 298                         if (!mtd->write_user_prot_reg) {
 299                                 ret = -EOPNOTSUPP;
 300                                 break;
 301                         }
 302                         ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
 303                         break;
 304
 305                 case MTD_MODE_RAW:
 306                 {
 307                         struct mtd_oob_ops ops;
 308
 309                         ops.mode = MTD_OOB_RAW;
 310                         ops.datbuf = kbuf;
 311                         ops.oobbuf = NULL;
 312                         ops.len = len;
 313
 314                         ret = mtd->write_oob(mtd, *ppos, &ops);
 315                         retlen = ops.retlen;
 316                         break;
 317                 }
 318
 319                 default:
 320                         ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
 321                 }
 322                 if (!ret) {
 323                         *ppos += retlen;
 324                         total_retlen += retlen;
 325                         count -= retlen;
 326                         buf += retlen;
 327                 }
 328                 else {
 329                         kfree(kbuf);
 330                         return ret;
 331                 }
 332         }
 333
 334         kfree(kbuf);
 335         return total_retlen;
 336 } /* mtd_write */
 337
 338 /*======================================================================
 339
 340     IOCTL calls for getting device parameters.
 341
 342 ======================================================================*/
 343 static void mtdchar_erase_callback (struct erase_info *instr)
 344 {
 345         wake_up((wait_queue_head_t *)instr->priv);
 346 }
 347
 348 #ifdef CONFIG_HAVE_MTD_OTP
 349 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
 350 {
 351         struct mtd_info *mtd = mfi->mtd;
 352         int ret = 0;
 353
 354         switch (mode) {
 355         case MTD_OTP_FACTORY:
 356                 if (!mtd->read_fact_prot_reg)
 357                         ret = -EOPNOTSUPP;
 358                 else
 359                         mfi->mode = MTD_MODE_OTP_FACTORY;
 360                 break;
 361         case MTD_OTP_USER:
 362                 if (!mtd->read_fact_prot_reg)
 363                         ret = -EOPNOTSUPP;
 364                 else
 365                         mfi->mode = MTD_MODE_OTP_USER;
 366                 break;
 367         default:
 368                 ret = -EINVAL;
 369         case MTD_OTP_OFF:
 370                 break;
 371         }
 372         return ret;
 373 }
 374 #else
 375 # define otp_select_filemode(f,m)       -EOPNOTSUPP
 376 #endif
 377
 378 static int mtd_do_writeoob(struct file *file, struct mtd_info *mtd,
 379         uint64_t start, uint32_t length, void __user *ptr,
 380         uint32_t __user *retp)
 381 {
 382         struct mtd_oob_ops ops;
 383         uint32_t retlen;
 384         int ret = 0;
 385
 386         if (!(file->f_mode & FMODE_WRITE))
 387                 return -EPERM;
 388
 389         if (length > 4096)
 390                 return -EINVAL;
 391
 392         if (!mtd->write_oob)
 393                 ret = -EOPNOTSUPP;
 394         else
 395                 ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
 396
 397         if (ret)
 398                 return ret;
 399
 400         ops.ooblen = length;
 401         ops.ooboffs = start & (mtd->oobsize - 1);
 402         ops.datbuf = NULL;
 403         ops.mode = MTD_OOB_PLACE;
 404
 405         if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
 406                 return -EINVAL;
 407
 408         ops.oobbuf = memdup_user(ptr, length);
 409         if (IS_ERR(ops.oobbuf))
 410                 return PTR_ERR(ops.oobbuf);
 411
 412         start &= ~((uint64_t)mtd->oobsize - 1);
 413         ret = mtd->write_oob(mtd, start, &ops);
 414
 415         if (ops.oobretlen > 0xFFFFFFFFU)
 416                 ret = -EOVERFLOW;
 417         retlen = ops.oobretlen;
 418         if (copy_to_user(retp, &retlen, sizeof(length)))
 419                 ret = -EFAULT;
 420
 421         kfree(ops.oobbuf);
 422         return ret;
 423 }
 424
 425 static int mtd_do_readoob(struct mtd_info *mtd, uint64_t start,
 426         uint32_t length, void __user *ptr, uint32_t __user *retp)
 427 {
 428         struct mtd_oob_ops ops;
 429         int ret = 0;
 430
 431         if (length > 4096)
 432                 return -EINVAL;
 433
 434         if (!mtd->read_oob)
 435                 ret = -EOPNOTSUPP;
 436         else
 437                 ret = access_ok(VERIFY_WRITE, ptr,
 438                                 length) ? 0 : -EFAULT;
 439         if (ret)
 440                 return ret;
 441
 442         ops.ooblen = length;
 443         ops.ooboffs = start & (mtd->oobsize - 1);
 444         ops.datbuf = NULL;
 445         ops.mode = MTD_OOB_PLACE;
 446
 447         if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
 448                 return -EINVAL;
 449
 450         ops.oobbuf = kmalloc(length, GFP_KERNEL);
 451         if (!ops.oobbuf)
 452                 return -ENOMEM;
 453
 454         start &= ~((uint64_t)mtd->oobsize - 1);
 455         ret = mtd->read_oob(mtd, start, &ops);
 456
 457         if (put_user(ops.oobretlen, retp))
 458                 ret = -EFAULT;
 459         else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
 460                                             ops.oobretlen))
 461                 ret = -EFAULT;
 462
 463         kfree(ops.oobbuf);
 464         return ret;
 465 }
 466
 467 static int mtd_ioctl(struct inode *inode, struct file *file,
 468                      u_int cmd, u_long arg)
 469 {
 470         struct mtd_file_info *mfi = file->private_data;
 471         struct mtd_info *mtd = mfi->mtd;
 472         void __user *argp = (void __user *)arg;
 473         int ret = 0;
 474         u_long size;
 475         struct mtd_info_user info;
 476
 477         DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
 478
 479         size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
 480         if (cmd & IOC_IN) {
 481                 if (!access_ok(VERIFY_READ, argp, size))
 482                         return -EFAULT;
 483         }
 484         if (cmd & IOC_OUT) {
 485                 if (!access_ok(VERIFY_WRITE, argp, size))
 486                         return -EFAULT;
 487         }
 488
 489         switch (cmd) {
 490         case MEMGETREGIONCOUNT:
 491                 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
 492                         return -EFAULT;
 493                 break;
 494
 495         case MEMGETREGIONINFO:
 496         {
 497                 uint32_t ur_idx;
 498                 struct mtd_erase_region_info *kr;
 499                 struct region_info_user __user *ur = argp;
 500
 501                 if (get_user(ur_idx, &(ur->regionindex)))
 502                         return -EFAULT;
 503
 504                 kr = &(mtd->eraseregions[ur_idx]);
 505
 506                 if (put_user(kr->offset, &(ur->offset))
 507                     || put_user(kr->erasesize, &(ur->erasesize))
 508                     || put_user(kr->numblocks, &(ur->numblocks)))
 509                         return -EFAULT;
 510
 511                 break;
 512         }
 513
 514         case MEMGETINFO:
 515                 info.type       = mtd->type;
 516                 info.flags      = mtd->flags;
 517                 info.size       = mtd->size;
 518                 info.erasesize  = mtd->erasesize;
 519                 info.writesize  = mtd->writesize;
 520                 info.oobsize    = mtd->oobsize;
 521                 /* The below fields are obsolete */
 522                 info.ecctype    = -1;
 523                 info.eccsize    = 0;
 524                 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
 525                         return -EFAULT;
 526                 break;
 527
 528         case MEMERASE:
 529         case MEMERASE64:
 530         {
 531                 struct erase_info *erase;
 532
 533                 if(!(file->f_mode & FMODE_WRITE))
 534                         return -EPERM;
 535
 536                 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
 537                 if (!erase)
 538                         ret = -ENOMEM;
 539                 else {
 540                         wait_queue_head_t waitq;
 541                         DECLARE_WAITQUEUE(wait, current);
 542
 543                         init_waitqueue_head(&waitq);
 544
 545                         if (cmd == MEMERASE64) {
 546                                 struct erase_info_user64 einfo64;
 547
 548                                 if (copy_from_user(&einfo64, argp,
 549                                             sizeof(struct erase_info_user64))) {
 550                                         kfree(erase);
 551                                         return -EFAULT;
 552                                 }
 553                                 erase->addr = einfo64.start;
 554                                 erase->len = einfo64.length;
 555                         } else {
 556                                 struct erase_info_user einfo32;
 557
 558                                 if (copy_from_user(&einfo32, argp,
 559                                             sizeof(struct erase_info_user))) {
 560                                         kfree(erase);
 561                                         return -EFAULT;
 562                                 }
 563                                 erase->addr = einfo32.start;
 564                                 erase->len = einfo32.length;
 565                         }
 566                         erase->mtd = mtd;
 567                         erase->callback = mtdchar_erase_callback;
 568                         erase->priv = (unsigned long)&waitq;
 569
 570                         /*
 571                           FIXME: Allow INTERRUPTIBLE. Which means
 572                           not having the wait_queue head on the stack.
 573
 574                           If the wq_head is on the stack, and we
 575                           leave because we got interrupted, then the
 576                           wq_head is no longer there when the
 577                           callback routine tries to wake us up.
 578                         */
 579                         ret = mtd->erase(mtd, erase);
 580                         if (!ret) {
 581                                 set_current_state(TASK_UNINTERRUPTIBLE);
 582                                 add_wait_queue(&waitq, &wait);
 583                                 if (erase->state != MTD_ERASE_DONE &&
 584                                     erase->state != MTD_ERASE_FAILED)
 585                                         schedule();
 586                                 remove_wait_queue(&waitq, &wait);
 587                                 set_current_state(TASK_RUNNING);
 588
 589                                 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
 590                         }
 591                         kfree(erase);
 592                 }
 593                 break;
 594         }
 595
 596         case MEMWRITEOOB:
 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->length */
 602                 if (copy_from_user(&buf, argp, sizeof(buf)))
 603                         ret = -EFAULT;
 604                 else
 605                         ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
 606                                 buf.ptr, &buf_user->length);
 607                 break;
 608         }
 609
 610         case MEMREADOOB:
 611         {
 612                 struct mtd_oob_buf buf;
 613                 struct mtd_oob_buf __user *buf_user = argp;
 614
 615                 /* NOTE: writes return length to buf_user->start */
 616                 if (copy_from_user(&buf, argp, sizeof(buf)))
 617                         ret = -EFAULT;
 618                 else
 619                         ret = mtd_do_readoob(mtd, buf.start, buf.length,
 620                                 buf.ptr, &buf_user->start);
 621                 break;
 622         }
 623
 624         case MEMWRITEOOB64:
 625         {
 626                 struct mtd_oob_buf64 buf;
 627                 struct mtd_oob_buf64 __user *buf_user = argp;
 628
 629                 if (copy_from_user(&buf, argp, sizeof(buf)))
 630                         ret = -EFAULT;
 631                 else
 632                         ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
 633                                 (void __user *)(uintptr_t)buf.usr_ptr,
 634                                 &buf_user->length);
 635                 break;
 636         }
 637
 638         case MEMREADOOB64:
 639         {
 640                 struct mtd_oob_buf64 buf;
 641                 struct mtd_oob_buf64 __user *buf_user = argp;
 642
 643                 if (copy_from_user(&buf, argp, sizeof(buf)))
 644                         ret = -EFAULT;
 645                 else
 646                         ret = mtd_do_readoob(mtd, buf.start, buf.length,
 647                                 (void __user *)(uintptr_t)buf.usr_ptr,
 648                                 &buf_user->length);
 649                 break;
 650         }
 651
 652         case MEMLOCK:
 653         {
 654                 struct erase_info_user einfo;
 655
 656                 if (copy_from_user(&einfo, argp, sizeof(einfo)))
 657                         return -EFAULT;
 658
 659                 if (!mtd->lock)
 660                         ret = -EOPNOTSUPP;
 661                 else
 662                         ret = mtd->lock(mtd, einfo.start, einfo.length);
 663                 break;
 664         }
 665
 666         case MEMUNLOCK:
 667         {
 668                 struct erase_info_user einfo;
 669
 670                 if (copy_from_user(&einfo, argp, sizeof(einfo)))
 671                         return -EFAULT;
 672
 673                 if (!mtd->unlock)
 674                         ret = -EOPNOTSUPP;
 675                 else
 676                         ret = mtd->unlock(mtd, einfo.start, einfo.length);
 677                 break;
 678         }
 679
 680         case MEMISLOCKED:
 681         {
 682                 struct erase_info_user einfo;
 683
 684                 if (copy_from_user(&einfo, argp, sizeof(einfo)))
 685                         return -EFAULT;
 686
 687                 if (!mtd->is_locked)
 688                         ret = -EOPNOTSUPP;
 689                 else
 690                         ret = mtd->is_locked(mtd, einfo.start, einfo.length);
 691                 break;
 692         }
 693
 694         /* Legacy interface */
 695         case MEMGETOOBSEL:
 696         {
 697                 struct nand_oobinfo oi;
 698
 699                 if (!mtd->ecclayout)
 700                         return -EOPNOTSUPP;
 701                 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
 702                         return -EINVAL;
 703
 704                 oi.useecc = MTD_NANDECC_AUTOPLACE;
 705                 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
 706                 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
 707                        sizeof(oi.oobfree));
 708                 oi.eccbytes = mtd->ecclayout->eccbytes;
 709
 710                 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
 711                         return -EFAULT;
 712                 break;
 713         }
 714
 715         case MEMGETBADBLOCK:
 716         {
 717                 loff_t offs;
 718
 719                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
 720                         return -EFAULT;
 721                 if (!mtd->block_isbad)
 722                         ret = -EOPNOTSUPP;
 723                 else
 724                         return mtd->block_isbad(mtd, offs);
 725                 break;
 726         }
 727
 728         case MEMSETBADBLOCK:
 729         {
 730                 loff_t offs;
 731
 732                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
 733                         return -EFAULT;
 734                 if (!mtd->block_markbad)
 735                         ret = -EOPNOTSUPP;
 736                 else
 737                         return mtd->block_markbad(mtd, offs);
 738                 break;
 739         }
 740
 741 #ifdef CONFIG_HAVE_MTD_OTP
 742         case OTPSELECT:
 743         {
 744                 int mode;
 745                 if (copy_from_user(&mode, argp, sizeof(int)))
 746                         return -EFAULT;
 747
 748                 mfi->mode = MTD_MODE_NORMAL;
 749
 750                 ret = otp_select_filemode(mfi, mode);
 751
 752                 file->f_pos = 0;
 753                 break;
 754         }
 755
 756         case OTPGETREGIONCOUNT:
 757         case OTPGETREGIONINFO:
 758         {
 759                 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
 760                 if (!buf)
 761                         return -ENOMEM;
 762                 ret = -EOPNOTSUPP;
 763                 switch (mfi->mode) {
 764                 case MTD_MODE_OTP_FACTORY:
 765                         if (mtd->get_fact_prot_info)
 766                                 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
 767                         break;
 768                 case MTD_MODE_OTP_USER:
 769                         if (mtd->get_user_prot_info)
 770                                 ret = mtd->get_user_prot_info(mtd, buf, 4096);
 771                         break;
 772                 default:
 773                         break;
 774                 }
 775                 if (ret >= 0) {
 776                         if (cmd == OTPGETREGIONCOUNT) {
 777                                 int nbr = ret / sizeof(struct otp_info);
 778                                 ret = copy_to_user(argp, &nbr, sizeof(int));
 779                         } else
 780                                 ret = copy_to_user(argp, buf, ret);
 781                         if (ret)
 782                                 ret = -EFAULT;
 783                 }
 784                 kfree(buf);
 785                 break;
 786         }
 787
 788         case OTPLOCK:
 789         {
 790                 struct otp_info oinfo;
 791
 792                 if (mfi->mode != MTD_MODE_OTP_USER)
 793                         return -EINVAL;
 794                 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
 795                         return -EFAULT;
 796                 if (!mtd->lock_user_prot_reg)
 797                         return -EOPNOTSUPP;
 798                 ret = mtd->lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
 799                 break;
 800         }
 801 #endif
 802
 803         case ECCGETLAYOUT:
 804         {
 805                 if (!mtd->ecclayout)
 806                         return -EOPNOTSUPP;
 807
 808                 if (copy_to_user(argp, mtd->ecclayout,
 809                                  sizeof(struct nand_ecclayout)))
 810                         return -EFAULT;
 811                 break;
 812         }
 813
 814         case ECCGETSTATS:
 815         {
 816                 if (copy_to_user(argp, &mtd->ecc_stats,
 817                                  sizeof(struct mtd_ecc_stats)))
 818                         return -EFAULT;
 819                 break;
 820         }
 821
 822         case MTDFILEMODE:
 823         {
 824                 mfi->mode = 0;
 825
 826                 switch(arg) {
 827                 case MTD_MODE_OTP_FACTORY:
 828                 case MTD_MODE_OTP_USER:
 829                         ret = otp_select_filemode(mfi, arg);
 830                         break;
 831
 832                 case MTD_MODE_RAW:
 833                         if (!mtd->read_oob || !mtd->write_oob)
 834                                 return -EOPNOTSUPP;
 835                         mfi->mode = arg;
 836
 837                 case MTD_MODE_NORMAL:
 838                         break;
 839                 default:
 840                         ret = -EINVAL;
 841                 }
 842                 file->f_pos = 0;
 843                 break;
 844         }
 845
 846         default:
 847                 ret = -ENOTTY;
 848         }
 849
 850         return ret;
 851 } /* memory_ioctl */
 852
 853 #ifdef CONFIG_COMPAT
 854
 855 struct mtd_oob_buf32 {
 856         u_int32_t start;
 857         u_int32_t length;
 858         compat_caddr_t ptr;     /* unsigned char* */
 859 };
 860
 861 #define MEMWRITEOOB32           _IOWR('M', 3, struct mtd_oob_buf32)
 862 #define MEMREADOOB32            _IOWR('M', 4, struct mtd_oob_buf32)
 863
 864 static long mtd_compat_ioctl(struct file *file, unsigned int cmd,
 865         unsigned long arg)
 866 {
 867         struct inode *inode = file->f_path.dentry->d_inode;
 868         struct mtd_file_info *mfi = file->private_data;
 869         struct mtd_info *mtd = mfi->mtd;
 870         void __user *argp = compat_ptr(arg);
 871         int ret = 0;
 872
 873         lock_kernel();
 874
 875         switch (cmd) {
 876         case MEMWRITEOOB32:
 877         {
 878                 struct mtd_oob_buf32 buf;
 879                 struct mtd_oob_buf32 __user *buf_user = argp;
 880
 881                 if (copy_from_user(&buf, argp, sizeof(buf)))
 882                         ret = -EFAULT;
 883                 else
 884                         ret = mtd_do_writeoob(file, mtd, buf.start,
 885                                 buf.length, compat_ptr(buf.ptr),
 886                                 &buf_user->length);
 887                 break;
 888         }
 889
 890         case MEMREADOOB32:
 891         {
 892                 struct mtd_oob_buf32 buf;
 893                 struct mtd_oob_buf32 __user *buf_user = argp;
 894
 895                 /* NOTE: writes return length to buf->start */
 896                 if (copy_from_user(&buf, argp, sizeof(buf)))
 897                         ret = -EFAULT;
 898                 else
 899                         ret = mtd_do_readoob(mtd, buf.start,
 900                                 buf.length, compat_ptr(buf.ptr),
 901                                 &buf_user->start);
 902                 break;
 903         }
 904         default:
 905                 ret = mtd_ioctl(inode, file, cmd, (unsigned long)argp);
 906         }
 907
 908         unlock_kernel();
 909
 910         return ret;
 911 }
 912
 913 #endif /* CONFIG_COMPAT */
 914
 915 /*
 916  * try to determine where a shared mapping can be made
 917  * - only supported for NOMMU at the moment (MMU can't doesn't copy private
 918  *   mappings)
 919  */
 920 #ifndef CONFIG_MMU
 921 static unsigned long mtd_get_unmapped_area(struct file *file,
 922                                            unsigned long addr,
 923                                            unsigned long len,
 924                                            unsigned long pgoff,
 925                                            unsigned long flags)
 926 {
 927         struct mtd_file_info *mfi = file->private_data;
 928         struct mtd_info *mtd = mfi->mtd;
 929
 930         if (mtd->get_unmapped_area) {
 931                 unsigned long offset;
 932
 933                 if (addr != 0)
 934                         return (unsigned long) -EINVAL;
 935
 936                 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
 937                         return (unsigned long) -EINVAL;
 938
 939                 offset = pgoff << PAGE_SHIFT;
 940                 if (offset > mtd->size - len)
 941                         return (unsigned long) -EINVAL;
 942
 943                 return mtd->get_unmapped_area(mtd, len, offset, flags);
 944         }
 945
 946         /* can't map directly */
 947         return (unsigned long) -ENOSYS;
 948 }
 949 #endif
 950
 951 /*
 952  * set up a mapping for shared memory segments
 953  */
 954 static int mtd_mmap(struct file *file, struct vm_area_struct *vma)
 955 {
 956 #ifdef CONFIG_MMU
 957         struct mtd_file_info *mfi = file->private_data;
 958         struct mtd_info *mtd = mfi->mtd;
 959         struct map_info *map = mtd->priv;
 960         unsigned long start;
 961         unsigned long off;
 962         u32 len;
 963
 964         if (mtd->type == MTD_RAM || mtd->type == MTD_ROM) {
 965                 off = vma->vm_pgoff << PAGE_SHIFT;
 966                 start = map->phys;
 967                 len = PAGE_ALIGN((start & ~PAGE_MASK) + map->size);
 968                 start &= PAGE_MASK;
 969                 if ((vma->vm_end - vma->vm_start + off) > len)
 970                         return -EINVAL;
 971
 972                 off += start;
 973                 vma->vm_pgoff = off >> PAGE_SHIFT;
 974                 vma->vm_flags |= VM_IO | VM_RESERVED;
 975
 976 #ifdef pgprot_noncached
 977                 if (file->f_flags & O_DSYNC || off >= __pa(high_memory))
 978                         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 979 #endif
 980                 if (io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
 981                                        vma->vm_end - vma->vm_start,
 982                                        vma->vm_page_prot))
 983                         return -EAGAIN;
 984
 985                 return 0;
 986         }
 987         return -ENOSYS;
 988 #else
 989         return vma->vm_flags & VM_SHARED ? 0 : -ENOSYS;
 990 #endif
 991 }
 992
 993 static const struct file_operations mtd_fops = {
 994         .owner          = THIS_MODULE,
 995         .llseek         = mtd_lseek,
 996         .read           = mtd_read,
 997         .write          = mtd_write,
 998         .ioctl          = mtd_ioctl,
 999 #ifdef CONFIG_COMPAT
1000         .compat_ioctl   = mtd_compat_ioctl,
1001 #endif
1002         .open           = mtd_open,
1003         .release        = mtd_close,
1004         .mmap           = mtd_mmap,
1005 #ifndef CONFIG_MMU
1006         .get_unmapped_area = mtd_get_unmapped_area,
1007 #endif
1008 };
1009
1010 static int mtd_inodefs_get_sb(struct file_system_type *fs_type, int flags,
1011                                const char *dev_name, void *data,
1012                                struct vfsmount *mnt)
1013 {
1014         return get_sb_pseudo(fs_type, "mtd_inode:", NULL, MTD_INODE_FS_MAGIC,
1015                              mnt);
1016 }
1017
1018 static struct file_system_type mtd_inodefs_type = {
1019        .name = "mtd_inodefs",
1020        .get_sb = mtd_inodefs_get_sb,
1021        .kill_sb = kill_anon_super,
1022 };
1023
1024 static void mtdchar_notify_add(struct mtd_info *mtd)
1025 {
1026 }
1027
1028 static void mtdchar_notify_remove(struct mtd_info *mtd)
1029 {
1030         struct inode *mtd_ino = ilookup(mtd_inode_mnt->mnt_sb, mtd->index);
1031
1032         if (mtd_ino) {
1033                 /* Destroy the inode if it exists */
1034                 mtd_ino->i_nlink = 0;
1035                 iput(mtd_ino);
1036         }
1037 }
1038
1039 static struct mtd_notifier mtdchar_notifier = {
1040         .add = mtdchar_notify_add,
1041         .remove = mtdchar_notify_remove,
1042 };
1043
1044 static int __init init_mtdchar(void)
1045 {
1046         int ret;
1047
1048         ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1049                                    "mtd", &mtd_fops);
1050         if (ret < 0) {
1051                 pr_notice("Can't allocate major number %d for "
1052                                 "Memory Technology Devices.\n", MTD_CHAR_MAJOR);
1053                 return ret;
1054         }
1055
1056         ret = register_filesystem(&mtd_inodefs_type);
1057         if (ret) {
1058                 pr_notice("Can't register mtd_inodefs filesystem: %d\n", ret);
1059                 goto err_unregister_chdev;
1060         }
1061
1062         mtd_inode_mnt = kern_mount(&mtd_inodefs_type);
1063         if (IS_ERR(mtd_inode_mnt)) {
1064                 ret = PTR_ERR(mtd_inode_mnt);
1065                 pr_notice("Error mounting mtd_inodefs filesystem: %d\n", ret);
1066                 goto err_unregister_filesystem;
1067         }
1068         register_mtd_user(&mtdchar_notifier);
1069
1070         return ret;
1071
1072 err_unregister_filesystem:
1073         unregister_filesystem(&mtd_inodefs_type);
1074 err_unregister_chdev:
1075         __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1076         return ret;
1077 }
1078
1079 static void __exit cleanup_mtdchar(void)
1080 {
1081         unregister_mtd_user(&mtdchar_notifier);
1082         mntput(mtd_inode_mnt);
1083         unregister_filesystem(&mtd_inodefs_type);
1084         __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1085 }
1086
1087 module_init(init_mtdchar);
1088 module_exit(cleanup_mtdchar);
1089
1090 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
1091
1092 MODULE_LICENSE("GPL");
1093 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1094 MODULE_DESCRIPTION("Direct character-device access to MTD devices");
1095 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);