target/linux/generic/patches-2.6.30/065-rootfs_split.patch

   1 --- a/drivers/mtd/Kconfig
   2 +++ b/drivers/mtd/Kconfig
   3 @@ -53,6 +53,16 @@ config MTD_TESTS
   4           should normally be compiled as kernel modules. The modules perform
   5           various checks and verifications when loaded.
   6
   7 +config MTD_ROOTFS_ROOT_DEV
   8 +       bool "Automatically set 'rootfs' partition to be root filesystem"
   9 +       depends on MTD_PARTITIONS
  10 +       default y
  11 +
  12 +config MTD_ROOTFS_SPLIT
  13 +       bool "Automatically split 'rootfs' partition for squashfs"
  14 +       depends on MTD_PARTITIONS
  15 +       default y
  16 +
  17  config MTD_REDBOOT_PARTS
  18         tristate "RedBoot partition table parsing"
  19         depends on MTD_PARTITIONS
  20 --- a/drivers/mtd/mtdpart.c
  21 +++ b/drivers/mtd/mtdpart.c
  22 @@ -18,6 +18,8 @@
  23  #include <linux/mtd/mtd.h>
  24  #include <linux/mtd/partitions.h>
  25  #include <linux/mtd/compatmac.h>
  26 +#include <linux/root_dev.h>
  27 +#include <linux/magic.h>
  28
  29  /* Our partition linked list */
  30  static LIST_HEAD(mtd_partitions);
  31 @@ -37,7 +39,7 @@ struct mtd_part {
  32   * the pointer to that structure with this macro.
  33   */
  34  #define PART(x)  ((struct mtd_part *)(x))
  35 -
  36 +#define IS_PART(mtd) (mtd->read == part_read)
  37
  38  /*
  39   * MTD methods which simply translate the effective address and pass through
  40 @@ -512,6 +514,157 @@ out_register:
  41         return slave;
  42  }
  43
  44 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
  45 +#define ROOTFS_SPLIT_NAME "rootfs_data"
  46 +#define ROOTFS_REMOVED_NAME "<removed>"
  47 +
  48 +struct squashfs_super_block {
  49 +       __le32 s_magic;
  50 +       __le32 pad0[9];
  51 +       __le64 bytes_used;
  52 +};
  53 +
  54 +
  55 +static int split_squashfs(struct mtd_info *master, int offset, int *split_offset)
  56 +{
  57 +       struct squashfs_super_block sb;
  58 +       int len, ret;
  59 +
  60 +       ret = master->read(master, offset, sizeof(sb), &len, (void *) &sb);
  61 +       if (ret || (len != sizeof(sb))) {
  62 +               printk(KERN_ALERT "split_squashfs: error occured while reading "
  63 +                       "from \"%s\"\n", master->name);
  64 +               return -EINVAL;
  65 +       }
  66 +
  67 +       if (SQUASHFS_MAGIC != le32_to_cpu(sb.s_magic) ) {
  68 +               printk(KERN_ALERT "split_squashfs: no squashfs found in \"%s\"\n",
  69 +                       master->name);
  70 +               *split_offset = 0;
  71 +               return 0;
  72 +       }
  73 +
  74 +       if (le64_to_cpu((sb.bytes_used)) <= 0) {
  75 +               printk(KERN_ALERT "split_squashfs: squashfs is empty in \"%s\"\n",
  76 +                       master->name);
  77 +               *split_offset = 0;
  78 +               return 0;
  79 +       }
  80 +
  81 +       len = (u32) le64_to_cpu(sb.bytes_used);
  82 +       len += (offset & 0x000fffff);
  83 +       len +=  (master->erasesize - 1);
  84 +       len &= ~(master->erasesize - 1);
  85 +       len -= (offset & 0x000fffff);
  86 +       *split_offset = offset + len;
  87 +
  88 +       return 0;
  89 +}
  90 +
  91 +static int split_rootfs_data(struct mtd_info *master, struct mtd_info *rpart, const struct mtd_partition *part,
  92 +               int index)
  93 +{
  94 +       struct mtd_partition *dpart;
  95 +       struct mtd_part *slave = NULL;
  96 +       struct mtd_part *spart;
  97 +       int split_offset = 0;
  98 +       int ret;
  99 +
 100 +       spart = PART(rpart);
 101 +       ret = split_squashfs(master, spart->offset, &split_offset);
 102 +       if (ret)
 103 +               return ret;
 104 +
 105 +       if (split_offset <= 0)
 106 +               return 0;
 107 +
 108 +       dpart = kmalloc(sizeof(*part)+sizeof(ROOTFS_SPLIT_NAME)+1, GFP_KERNEL);
 109 +       if (dpart == NULL) {
 110 +               printk(KERN_INFO "split_squashfs: no memory for partition \"%s\"\n",
 111 +                       ROOTFS_SPLIT_NAME);
 112 +               return -ENOMEM;
 113 +       }
 114 +
 115 +       memcpy(dpart, part, sizeof(*part));
 116 +       dpart->name = (unsigned char *)&dpart[1];
 117 +       strcpy(dpart->name, ROOTFS_SPLIT_NAME);
 118 +
 119 +       dpart->size = rpart->size - (split_offset - spart->offset);
 120 +       dpart->offset = split_offset;
 121 +
 122 +       if (dpart == NULL)
 123 +               return 1;
 124 +
 125 +       printk(KERN_INFO "mtd: partition \"%s\" created automatically, ofs=%llX, len=%llX \n",
 126 +               ROOTFS_SPLIT_NAME, dpart->offset, dpart->size);
 127 +
 128 +       slave = add_one_partition(master, dpart, index, split_offset);
 129 +       if (!slave) {
 130 +               kfree(dpart);
 131 +               return -ENOMEM;
 132 +       }
 133 +       rpart->split = &slave->mtd;
 134 +
 135 +       return 0;
 136 +}
 137 +
 138 +static int refresh_rootfs_split(struct mtd_info *mtd)
 139 +{
 140 +       struct mtd_partition tpart;
 141 +       struct mtd_part *part;
 142 +       char *name;
 143 +       int index = 0;
 144 +       int offset, size;
 145 +       int ret;
 146 +
 147 +       part = PART(mtd);
 148 +
 149 +       /* check for the new squashfs offset first */
 150 +       ret = split_squashfs(part->master, part->offset, &offset);
 151 +       if (ret)
 152 +               return ret;
 153 +
 154 +       if ((offset > 0) && !mtd->split) {
 155 +               printk(KERN_INFO "%s: creating new split partition for \"%s\"\n", __func__, mtd->name);
 156 +               /* if we don't have a rootfs split partition, create a new one */
 157 +               tpart.name = (char *) mtd->name;
 158 +               tpart.size = mtd->size;
 159 +               tpart.offset = part->offset;
 160 +
 161 +               /* find the index of the last partition */
 162 +               if (!list_empty(&mtd_partitions))
 163 +                       index = list_first_entry(&mtd_partitions, struct mtd_part, list)->index + 1;
 164 +
 165 +               return split_rootfs_data(part->master, &part->mtd, &tpart, index);
 166 +       } else if ((offset > 0) && mtd->split) {
 167 +               /* update the offsets of the existing partition */
 168 +               size = mtd->size + part->offset - offset;
 169 +
 170 +               part = PART(mtd->split);
 171 +               part->offset = offset;
 172 +               part->mtd.size = size;
 173 +               printk(KERN_INFO "%s: %s partition \"" ROOTFS_SPLIT_NAME "\", offset: 0x%06x (0x%06x)\n",
 174 +                       __func__, (!strcmp(part->mtd.name, ROOTFS_SPLIT_NAME) ? "updating" : "creating"),
 175 +                       (u32) part->offset, (u32) part->mtd.size);
 176 +               name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
 177 +               strcpy(name, ROOTFS_SPLIT_NAME);
 178 +               part->mtd.name = name;
 179 +       } else if ((offset <= 0) && mtd->split) {
 180 +               printk(KERN_INFO "%s: removing partition \"%s\"\n", __func__, mtd->split->name);
 181 +
 182 +               /* mark existing partition as removed */
 183 +               part = PART(mtd->split);
 184 +               name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
 185 +               strcpy(name, ROOTFS_REMOVED_NAME);
 186 +               part->mtd.name = name;
 187 +               part->offset = 0;
 188 +               part->mtd.size = 0;
 189 +       }
 190 +
 191 +       return 0;
 192 +}
 193 +#endif /* CONFIG_MTD_ROOTFS_SPLIT */
 194 +
 195  /*
 196   * This function, given a master MTD object and a partition table, creates
 197   * and registers slave MTD objects which are bound to the master according to
 198 @@ -527,14 +680,29 @@ int add_mtd_partitions(struct mtd_info *
 199  {
 200         struct mtd_part *slave;
 201         uint64_t cur_offset = 0;
 202 -       int i;
 203 +       int i, j, ret;
 204
 205         printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 206
 207 -       for (i = 0; i < nbparts; i++) {
 208 -               slave = add_one_partition(master, parts + i, i, cur_offset);
 209 +       for (i = 0, j = 0; i < nbparts; i++) {
 210 +               slave = add_one_partition(master, parts + i, j++, cur_offset);
 211                 if (!slave)
 212                         return -ENOMEM;
 213 +
 214 +               if (!strcmp(parts[i].name, "rootfs") && slave->registered) {
 215 +#ifdef CONFIG_MTD_ROOTFS_ROOT_DEV
 216 +                       if (ROOT_DEV == 0) {
 217 +                               printk(KERN_NOTICE "mtd: partition \"rootfs\" "
 218 +                                       "set to be root filesystem\n");
 219 +                               ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, slave->mtd.index);
 220 +                       }
 221 +#endif
 222 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
 223 +                       ret = split_rootfs_data(master, &slave->mtd, &parts[i], j);
 224 +                       if (ret == 0)
 225 +                               j++;
 226 +#endif
 227 +               }
 228                 cur_offset = slave->offset + slave->mtd.size;
 229         }
 230
 231 @@ -542,6 +710,32 @@ int add_mtd_partitions(struct mtd_info *
 232  }
 233  EXPORT_SYMBOL(add_mtd_partitions);
 234
 235 +int refresh_mtd_partitions(struct mtd_info *mtd)
 236 +{
 237 +       int ret = 0;
 238 +
 239 +       if (IS_PART(mtd)) {
 240 +               struct mtd_part *part;
 241 +               struct mtd_info *master;
 242 +
 243 +               part = PART(mtd);
 244 +               master = part->master;
 245 +               if (master->refresh_device)
 246 +                       ret = master->refresh_device(master);
 247 +       }
 248 +
 249 +       if (!ret && mtd->refresh_device)
 250 +               ret = mtd->refresh_device(mtd);
 251 +
 252 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
 253 +       if (!ret && IS_PART(mtd) && !strcmp(mtd->name, "rootfs"))
 254 +               refresh_rootfs_split(mtd);
 255 +#endif
 256 +
 257 +       return 0;
 258 +}
 259 +EXPORT_SYMBOL_GPL(refresh_mtd_partitions);
 260 +
 261  static DEFINE_SPINLOCK(part_parser_lock);
 262  static LIST_HEAD(part_parsers);
 263
 264 --- a/drivers/mtd/devices/block2mtd.c
 265 +++ b/drivers/mtd/devices/block2mtd.c
 266 @@ -29,6 +29,8 @@ struct block2mtd_dev {
 267         struct block_device *blkdev;
 268         struct mtd_info mtd;
 269         struct mutex write_mutex;
 270 +       rwlock_t bdev_mutex;
 271 +       char devname[0];
 272  };
 273
 274
 275 @@ -81,6 +83,12 @@ static int block2mtd_erase(struct mtd_in
 276         size_t len = instr->len;
 277         int err;
 278
 279 +       read_lock(&dev->bdev_mutex);
 280 +       if (!dev->blkdev) {
 281 +               err = -EINVAL;
 282 +               goto done;
 283 +       }
 284 +
 285         instr->state = MTD_ERASING;
 286         mutex_lock(&dev->write_mutex);
 287         err = _block2mtd_erase(dev, from, len);
 288 @@ -93,6 +101,10 @@ static int block2mtd_erase(struct mtd_in
 289
 290         instr->state = MTD_ERASE_DONE;
 291         mtd_erase_callback(instr);
 292 +
 293 +done:
 294 +       read_unlock(&dev->bdev_mutex);
 295 +
 296         return err;
 297  }
 298
 299 @@ -104,10 +116,14 @@ static int block2mtd_read(struct mtd_inf
 300         struct page *page;
 301         int index = from >> PAGE_SHIFT;
 302         int offset = from & (PAGE_SIZE-1);
 303 -       int cpylen;
 304 +       int cpylen, err = 0;
 305 +
 306 +       read_lock(&dev->bdev_mutex);
 307 +       if (!dev->blkdev || (from > mtd->size)) {
 308 +               err = -EINVAL;
 309 +               goto done;
 310 +       }
 311
 312 -       if (from > mtd->size)
 313 -               return -EINVAL;
 314         if (from + len > mtd->size)
 315                 len = mtd->size - from;
 316
 317 @@ -122,10 +138,14 @@ static int block2mtd_read(struct mtd_inf
 318                 len = len - cpylen;
 319
 320                 page = page_read(dev->blkdev->bd_inode->i_mapping, index);
 321 -               if (!page)
 322 -                       return -ENOMEM;
 323 -               if (IS_ERR(page))
 324 -                       return PTR_ERR(page);
 325 +               if (!page) {
 326 +                       err = -ENOMEM;
 327 +                       goto done;
 328 +               }
 329 +               if (IS_ERR(page)) {
 330 +                       err = PTR_ERR(page);
 331 +                       goto done;
 332 +               }
 333
 334                 memcpy(buf, page_address(page) + offset, cpylen);
 335                 page_cache_release(page);
 336 @@ -136,7 +156,10 @@ static int block2mtd_read(struct mtd_inf
 337                 offset = 0;
 338                 index++;
 339         }
 340 -       return 0;
 341 +
 342 +done:
 343 +       read_unlock(&dev->bdev_mutex);
 344 +       return err;
 345  }
 346
 347
 348 @@ -188,12 +211,22 @@ static int block2mtd_write(struct mtd_in
 349                 size_t *retlen, const u_char *buf)
 350  {
 351         struct block2mtd_dev *dev = mtd->priv;
 352 -       int err;
 353 +       int err = 0;
 354 +
 355 +       read_lock(&dev->bdev_mutex);
 356 +       if (!dev->blkdev) {
 357 +               err = -EINVAL;
 358 +               goto done;
 359 +       }
 360
 361         if (!len)
 362 -               return 0;
 363 -       if (to >= mtd->size)
 364 -               return -ENOSPC;
 365 +               goto done;
 366 +
 367 +       if (to >= mtd->size) {
 368 +               err = -ENOSPC;
 369 +               goto done;
 370 +       }
 371 +
 372         if (to + len > mtd->size)
 373                 len = mtd->size - to;
 374
 375 @@ -202,6 +235,9 @@ static int block2mtd_write(struct mtd_in
 376         mutex_unlock(&dev->write_mutex);
 377         if (err > 0)
 378                 err = 0;
 379 +
 380 +done:
 381 +       read_unlock(&dev->bdev_mutex);
 382         return err;
 383  }
 384
 385 @@ -210,52 +246,29 @@ static int block2mtd_write(struct mtd_in
 386  static void block2mtd_sync(struct mtd_info *mtd)
 387  {
 388         struct block2mtd_dev *dev = mtd->priv;
 389 -       sync_blockdev(dev->blkdev);
 390 -       return;
 391 -}
 392 -
 393 -
 394 -static void block2mtd_free_device(struct block2mtd_dev *dev)
 395 -{
 396 -       if (!dev)
 397 -               return;
 398 -
 399 -       kfree(dev->mtd.name);
 400
 401 -       if (dev->blkdev) {
 402 -               invalidate_mapping_pages(dev->blkdev->bd_inode->i_mapping,
 403 -                                       0, -1);
 404 -               close_bdev_exclusive(dev->blkdev, FMODE_READ|FMODE_WRITE);
 405 -       }
 406 +       read_lock(&dev->bdev_mutex);
 407 +       if (dev->blkdev)
 408 +               sync_blockdev(dev->blkdev);
 409 +       read_unlock(&dev->bdev_mutex);
 410
 411 -       kfree(dev);
 412 +       return;
 413  }
 414
 415
 416 -/* FIXME: ensure that mtd->size % erase_size == 0 */
 417 -static struct block2mtd_dev *add_device(char *devname, int erase_size, const char *mtdname)
 418 +static int _open_bdev(struct block2mtd_dev *dev)
 419  {
 420         struct block_device *bdev;
 421 -       struct block2mtd_dev *dev;
 422 -       struct mtd_partition *part;
 423 -       char *name;
 424 -
 425 -       if (!devname)
 426 -               return NULL;
 427 -
 428 -       dev = kzalloc(sizeof(struct block2mtd_dev), GFP_KERNEL);
 429 -       if (!dev)
 430 -               return NULL;
 431
 432         /* Get a handle on the device */
 433 -       bdev = open_bdev_exclusive(devname, FMODE_READ|FMODE_WRITE, NULL);
 434 +       bdev = open_bdev_exclusive(dev->devname, FMODE_READ|FMODE_WRITE, NULL);
 435  #ifndef MODULE
 436         if (IS_ERR(bdev)) {
 437
 438                 /* We might not have rootfs mounted at this point. Try
 439                    to resolve the device name by other means. */
 440
 441 -               dev_t devt = name_to_dev_t(devname);
 442 +               dev_t devt = name_to_dev_t(dev->devname);
 443                 if (devt) {
 444                         bdev = open_by_devnum(devt, FMODE_WRITE | FMODE_READ);
 445                 }
 446 @@ -263,17 +276,98 @@ static struct block2mtd_dev *add_device(
 447  #endif
 448
 449         if (IS_ERR(bdev)) {
 450 -               ERROR("error: cannot open device %s", devname);
 451 -               goto devinit_err;
 452 +               ERROR("error: cannot open device %s", dev->devname);
 453 +               return 1;
 454         }
 455         dev->blkdev = bdev;
 456
 457         if (MAJOR(bdev->bd_dev) == MTD_BLOCK_MAJOR) {
 458                 ERROR("attempting to use an MTD device as a block device");
 459 -               goto devinit_err;
 460 +               return 1;
 461         }
 462
 463 +       return 0;
 464 +}
 465 +
 466 +static void _close_bdev(struct block2mtd_dev *dev)
 467 +{
 468 +       struct block_device *bdev;
 469 +
 470 +       if (!dev->blkdev)
 471 +               return;
 472 +
 473 +       bdev = dev->blkdev;
 474 +       invalidate_mapping_pages(dev->blkdev->bd_inode->i_mapping, 0, -1);
 475 +       close_bdev_exclusive(dev->blkdev, FMODE_READ|FMODE_WRITE);
 476 +       dev->blkdev = NULL;
 477 +}
 478 +
 479 +static void block2mtd_free_device(struct block2mtd_dev *dev)
 480 +{
 481 +       if (!dev)
 482 +               return;
 483 +
 484 +       kfree(dev->mtd.name);
 485 +       _close_bdev(dev);
 486 +       kfree(dev);
 487 +}
 488 +
 489 +
 490 +static int block2mtd_refresh(struct mtd_info *mtd)
 491 +{
 492 +       struct block2mtd_dev *dev = mtd->priv;
 493 +       struct block_device *bdev;
 494 +       dev_t devt;
 495 +       int err = 0;
 496 +
 497 +       /* no other mtd function can run at this point */
 498 +       write_lock(&dev->bdev_mutex);
 499 +
 500 +       /* get the device number for the whole disk */
 501 +       devt = MKDEV(MAJOR(dev->blkdev->bd_dev), 0);
 502 +
 503 +       /* close the old block device */
 504 +       _close_bdev(dev);
 505 +
 506 +       /* open the whole disk, issue a partition rescan, then */
 507 +       bdev = open_by_devnum(devt, FMODE_WRITE | FMODE_READ);
 508 +       if (!bdev || !bdev->bd_disk)
 509 +               err = -EINVAL;
 510 +#ifndef CONFIG_MTD_BLOCK2MTD_MODULE
 511 +       else
 512 +               err = rescan_partitions(bdev->bd_disk, bdev);
 513 +#endif
 514 +       if (bdev)
 515 +               close_bdev_exclusive(bdev, FMODE_READ|FMODE_WRITE);
 516 +
 517 +       /* try to open the partition block device again */
 518 +       _open_bdev(dev);
 519 +       write_unlock(&dev->bdev_mutex);
 520 +
 521 +       return err;
 522 +}
 523 +
 524 +/* FIXME: ensure that mtd->size % erase_size == 0 */
 525 +static struct block2mtd_dev *add_device(char *devname, int erase_size, char *mtdname)
 526 +{
 527 +       struct block2mtd_dev *dev;
 528 +       struct mtd_partition *part;
 529 +       char *name;
 530 +
 531 +       if (!devname)
 532 +               return NULL;
 533 +
 534 +       dev = kzalloc(sizeof(struct block2mtd_dev) + strlen(devname) + 1, GFP_KERNEL);
 535 +       if (!dev)
 536 +               return NULL;
 537 +
 538 +       strcpy(dev->devname, devname);
 539 +
 540 +       if (_open_bdev(dev))
 541 +               goto devinit_err;
 542 +
 543         mutex_init(&dev->write_mutex);
 544 +       rwlock_init(&dev->bdev_mutex);
 545
 546         if (!mtdname)
 547                 mtdname = devname;
 548 @@ -297,6 +391,7 @@ static struct block2mtd_dev *add_device(
 549         dev->mtd.read = block2mtd_read;
 550         dev->mtd.priv = dev;
 551         dev->mtd.owner = THIS_MODULE;
 552 +       dev->mtd.refresh_device = block2mtd_refresh;
 553
 554         part = kzalloc(sizeof(struct mtd_partition), GFP_KERNEL);
 555         part->name = dev->mtd.name;
 556 --- a/drivers/mtd/mtdchar.c
 557 +++ b/drivers/mtd/mtdchar.c
 558 @@ -17,6 +17,7 @@
 559
 560  #include <linux/mtd/mtd.h>
 561  #include <linux/mtd/compatmac.h>
 562 +#include <linux/mtd/partitions.h>
 563
 564  #include <asm/uaccess.h>
 565
 566 @@ -750,6 +751,13 @@ static int mtd_ioctl(struct inode *inode
 567                 file->f_pos = 0;
 568                 break;
 569         }
 570 +#ifdef CONFIG_MTD_PARTITIONS
 571 +       case MTDREFRESH:
 572 +       {
 573 +               ret = refresh_mtd_partitions(mtd);
 574 +               break;
 575 +       }
 576 +#endif
 577
 578         default:
 579                 ret = -ENOTTY;
 580 --- a/include/linux/mtd/mtd.h
 581 +++ b/include/linux/mtd/mtd.h
 582 @@ -101,6 +101,7 @@ struct mtd_oob_ops {
 583         uint8_t         *oobbuf;
 584  };
 585
 586 +struct mtd_info;
 587  struct mtd_info {
 588         u_char type;
 589         uint32_t flags;
 590 @@ -241,6 +242,9 @@ struct mtd_info {
 591         struct device dev;
 592         int usecount;
 593
 594 +       int (*refresh_device)(struct mtd_info *mtd);
 595 +       struct mtd_info *split;
 596 +
 597         /* If the driver is something smart, like UBI, it may need to maintain
 598          * its own reference counting. The below functions are only for driver.
 599          * The driver may register its callbacks. These callbacks are not
 600 --- a/include/linux/mtd/partitions.h
 601 +++ b/include/linux/mtd/partitions.h
 602 @@ -34,6 +34,7 @@
 603   * erasesize aligned (e.g. use MTDPART_OFS_NEXTBLK).
 604   */
 605
 606 +struct mtd_partition;
 607  struct mtd_partition {
 608         char *name;                     /* identifier string */
 609         uint64_t size;                  /* partition size */
 610 @@ -41,6 +42,7 @@ struct mtd_partition {
 611         uint32_t mask_flags;            /* master MTD flags to mask out for this partition */
 612         struct nand_ecclayout *ecclayout;       /* out of band layout for this partition (NAND only)*/
 613         struct mtd_info **mtdp;         /* pointer to store the MTD object */
 614 +       int (*refresh_partition)(struct mtd_info *);
 615  };
 616
 617  #define MTDPART_OFS_NXTBLK     (-2)
 618 @@ -50,6 +52,7 @@ struct mtd_partition {
 619
 620  int add_mtd_partitions(struct mtd_info *, const struct mtd_partition *, int);
 621  int del_mtd_partitions(struct mtd_info *);
 622 +int refresh_mtd_partitions(struct mtd_info *);
 623
 624  /*
 625   * Functions dealing with the various ways of partitioning the space
 626 --- a/include/mtd/mtd-abi.h
 627 +++ b/include/mtd/mtd-abi.h
 628 @@ -95,6 +95,7 @@ struct otp_info {
 629  #define ECCGETLAYOUT           _IOR('M', 17, struct nand_ecclayout)
 630  #define ECCGETSTATS            _IOR('M', 18, struct mtd_ecc_stats)
 631  #define MTDFILEMODE            _IO('M', 19)
 632 +#define MTDREFRESH             _IO('M', 23)
 633
 634  /*
 635   * Obsolete legacy interface. Keep it in order not to break userspace