target/linux/generic-2.6/patches-2.6.27/065-rootfs_split.patch

   1 --- a/drivers/mtd/Kconfig
   2 +++ b/drivers/mtd/Kconfig
   3 @@ -45,6 +45,16 @@
   4           devices. Partitioning on NFTL 'devices' is a different - that's the
   5           'normal' form of partitioning used on a block device.
   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/squashfs_fs.h>
  27 +#include <linux/root_dev.h>
  28
  29  /* Our partition linked list */
  30  static LIST_HEAD(mtd_partitions);
  31 @@ -37,7 +39,7 @@
  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 @@ -489,6 +491,148 @@
  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 +static int split_squashfs(struct mtd_info *master, int offset, int *split_offset)
  48 +{
  49 +       char buf[512];
  50 +       struct squashfs_super_block *sb = (struct squashfs_super_block *) buf;
  51 +       int len, ret;
  52 +
  53 +       ret = master->read(master, offset, sizeof(*sb), &len, buf);
  54 +       if (ret || (len != sizeof(*sb))) {
  55 +               printk(KERN_ALERT "split_squashfs: error occured while reading "
  56 +                       "from \"%s\"\n", master->name);
  57 +               return -EINVAL;
  58 +       }
  59 +
  60 +       if (*((u32 *) buf) != SQUASHFS_MAGIC) {
  61 +               printk(KERN_ALERT "split_squashfs: no squashfs found in \"%s\"\n",
  62 +                       master->name);
  63 +               *split_offset = 0;
  64 +               return 0;
  65 +       }
  66 +
  67 +       if (sb->bytes_used <= 0) {
  68 +               printk(KERN_ALERT "split_squashfs: squashfs is empty in \"%s\"\n",
  69 +                       master->name);
  70 +               *split_offset = 0;
  71 +               return 0;
  72 +       }
  73 +
  74 +       len = (u32) sb->bytes_used;
  75 +       len += (offset & 0x000fffff);
  76 +       len +=  (master->erasesize - 1);
  77 +       len &= ~(master->erasesize - 1);
  78 +       len -= (offset & 0x000fffff);
  79 +       *split_offset = offset + len;
  80 +
  81 +       return 0;
  82 +}
  83 +
  84 +static int split_rootfs_data(struct mtd_info *master, struct mtd_info *rpart, const struct mtd_partition *part,
  85 +               int index)
  86 +{
  87 +       struct mtd_partition *dpart;
  88 +       struct mtd_part *slave = NULL;
  89 +       int split_offset = 0;
  90 +       int ret;
  91 +
  92 +       ret = split_squashfs(master, part->offset, &split_offset);
  93 +       if (ret)
  94 +               return ret;
  95 +
  96 +       if (split_offset <= 0)
  97 +               return 0;
  98 +
  99 +       dpart = kmalloc(sizeof(*part)+sizeof(ROOTFS_SPLIT_NAME)+1, GFP_KERNEL);
 100 +       if (dpart == NULL) {
 101 +               printk(KERN_INFO "split_squashfs: no memory for partition \"%s\"\n",
 102 +                       ROOTFS_SPLIT_NAME);
 103 +               return -ENOMEM;
 104 +       }
 105 +
 106 +       memcpy(dpart, part, sizeof(*part));
 107 +       dpart->name = (unsigned char *)&dpart[1];
 108 +       strcpy(dpart->name, ROOTFS_SPLIT_NAME);
 109 +
 110 +       dpart->size -= split_offset - dpart->offset;
 111 +       dpart->offset = split_offset;
 112 +
 113 +       if (dpart == NULL)
 114 +               return 1;
 115 +
 116 +       printk(KERN_INFO "mtd: partition \"%s\" created automatically, ofs=%X, len=%X \n",
 117 +               ROOTFS_SPLIT_NAME, dpart->offset, dpart->size);
 118 +
 119 +       slave = add_one_partition(master, dpart, index, split_offset);
 120 +       if (!slave) {
 121 +               kfree(dpart);
 122 +               return -ENOMEM;
 123 +       }
 124 +       rpart->split = &slave->mtd;
 125 +
 126 +       return 0;
 127 +}
 128 +
 129 +static int refresh_rootfs_split(struct mtd_info *mtd)
 130 +{
 131 +       struct mtd_partition tpart;
 132 +       struct mtd_part *part;
 133 +       char *name;
 134 +       int index = 0;
 135 +       int offset, size;
 136 +       int ret;
 137 +
 138 +       part = PART(mtd);
 139 +
 140 +       /* check for the new squashfs offset first */
 141 +       ret = split_squashfs(part->master, part->offset, &offset);
 142 +       if (ret)
 143 +               return ret;
 144 +
 145 +       if ((offset > 0) && !mtd->split) {
 146 +               printk(KERN_INFO "%s: creating new split partition for \"%s\"\n", __func__, mtd->name);
 147 +               /* if we don't have a rootfs split partition, create a new one */
 148 +               tpart.name = (char *) mtd->name;
 149 +               tpart.size = mtd->size;
 150 +               tpart.offset = part->offset;
 151 +
 152 +               /* find the index of the last partition */
 153 +               if (!list_empty(&mtd_partitions))
 154 +                       index = list_first_entry(&mtd_partitions, struct mtd_part, list)->index + 1;
 155 +
 156 +               return split_rootfs_data(part->master, &part->mtd, &tpart, index);
 157 +       } else if ((offset > 0) && mtd->split) {
 158 +               /* update the offsets of the existing partition */
 159 +               size = mtd->size + part->offset - offset;
 160 +
 161 +               part = PART(mtd->split);
 162 +               part->offset = offset;
 163 +               part->mtd.size = size;
 164 +               printk(KERN_INFO "%s: %s partition \"" ROOTFS_SPLIT_NAME "\", offset: 0x%06x (0x%06x)\n",
 165 +                       __func__, (!strcmp(part->mtd.name, ROOTFS_SPLIT_NAME) ? "updating" : "creating"),
 166 +                       part->offset, part->mtd.size);
 167 +               name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
 168 +               strcpy(name, ROOTFS_SPLIT_NAME);
 169 +               part->mtd.name = name;
 170 +       } else if ((offset <= 0) && mtd->split) {
 171 +               printk(KERN_INFO "%s: removing partition \"%s\"\n", __func__, mtd->split->name);
 172 +
 173 +               /* mark existing partition as removed */
 174 +               part = PART(mtd->split);
 175 +               name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
 176 +               strcpy(name, ROOTFS_REMOVED_NAME);
 177 +               part->mtd.name = name;
 178 +               part->offset = 0;
 179 +               part->mtd.size = 0;
 180 +       }
 181 +
 182 +       return 0;
 183 +}
 184 +#endif /* CONFIG_MTD_ROOTFS_SPLIT */
 185 +
 186  /*
 187   * This function, given a master MTD object and a partition table, creates
 188   * and registers slave MTD objects which are bound to the master according to
 189 @@ -502,14 +646,29 @@
 190  {
 191         struct mtd_part *slave;
 192         u_int32_t cur_offset = 0;
 193 -       int i;
 194 +       int i, j, ret;
 195
 196         printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 197
 198 -       for (i = 0; i < nbparts; i++) {
 199 -               slave = add_one_partition(master, parts + i, i, cur_offset);
 200 +       for (i = 0, j = 0; i < nbparts; i++) {
 201 +               slave = add_one_partition(master, parts + i, j++, cur_offset);
 202                 if (!slave)
 203                         return -ENOMEM;
 204 +
 205 +               if (!strcmp(parts[i].name, "rootfs") && slave->registered) {
 206 +#ifdef CONFIG_MTD_ROOTFS_ROOT_DEV
 207 +                       if (ROOT_DEV == 0) {
 208 +                               printk(KERN_NOTICE "mtd: partition \"rootfs\" "
 209 +                                       "set to be root filesystem\n");
 210 +                               ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, slave->mtd.index);
 211 +                       }
 212 +#endif
 213 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
 214 +                       ret = split_rootfs_data(master, &slave->mtd, &parts[i], j);
 215 +                       if (ret == 0)
 216 +                               j++;
 217 +#endif
 218 +               }
 219                 cur_offset = slave->offset + slave->mtd.size;
 220         }
 221
 222 @@ -517,6 +676,32 @@
 223  }
 224  EXPORT_SYMBOL(add_mtd_partitions);
 225
 226 +int refresh_mtd_partitions(struct mtd_info *mtd)
 227 +{
 228 +       int ret = 0;
 229 +
 230 +       if (IS_PART(mtd)) {
 231 +               struct mtd_part *part;
 232 +               struct mtd_info *master;
 233 +
 234 +               part = PART(mtd);
 235 +               master = part->master;
 236 +               if (master->refresh_device)
 237 +                       ret = master->refresh_device(master);
 238 +       }
 239 +
 240 +       if (!ret && mtd->refresh_device)
 241 +               ret = mtd->refresh_device(mtd);
 242 +
 243 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
 244 +       if (!ret && IS_PART(mtd) && !strcmp(mtd->name, "rootfs"))
 245 +               refresh_rootfs_split(mtd);
 246 +#endif
 247 +
 248 +       return 0;
 249 +}
 250 +EXPORT_SYMBOL_GPL(refresh_mtd_partitions);
 251 +
 252  static DEFINE_SPINLOCK(part_parser_lock);
 253  static LIST_HEAD(part_parsers);
 254
 255 --- a/drivers/mtd/devices/block2mtd.c
 256 +++ b/drivers/mtd/devices/block2mtd.c
 257 @@ -29,6 +29,8 @@
 258         struct block_device *blkdev;
 259         struct mtd_info mtd;
 260         struct mutex write_mutex;
 261 +       rwlock_t bdev_mutex;
 262 +       char devname[0];
 263  };
 264
 265
 266 @@ -81,6 +83,12 @@
 267         size_t len = instr->len;
 268         int err;
 269
 270 +       read_lock(&dev->bdev_mutex);
 271 +       if (!dev->blkdev) {
 272 +               err = -EINVAL;
 273 +               goto done;
 274 +       }
 275 +
 276         instr->state = MTD_ERASING;
 277         mutex_lock(&dev->write_mutex);
 278         err = _block2mtd_erase(dev, from, len);
 279 @@ -93,6 +101,10 @@
 280
 281         instr->state = MTD_ERASE_DONE;
 282         mtd_erase_callback(instr);
 283 +
 284 +done:
 285 +       read_unlock(&dev->bdev_mutex);
 286 +
 287         return err;
 288  }
 289
 290 @@ -104,10 +116,14 @@
 291         struct page *page;
 292         int index = from >> PAGE_SHIFT;
 293         int offset = from & (PAGE_SIZE-1);
 294 -       int cpylen;
 295 +       int cpylen, err = 0;
 296 +
 297 +       read_lock(&dev->bdev_mutex);
 298 +       if (!dev->blkdev || (from > mtd->size)) {
 299 +               err = -EINVAL;
 300 +               goto done;
 301 +       }
 302
 303 -       if (from > mtd->size)
 304 -               return -EINVAL;
 305         if (from + len > mtd->size)
 306                 len = mtd->size - from;
 307
 308 @@ -122,10 +138,14 @@
 309                 len = len - cpylen;
 310
 311                 page = page_read(dev->blkdev->bd_inode->i_mapping, index);
 312 -               if (!page)
 313 -                       return -ENOMEM;
 314 -               if (IS_ERR(page))
 315 -                       return PTR_ERR(page);
 316 +               if (!page) {
 317 +                       err = -ENOMEM;
 318 +                       goto done;
 319 +               }
 320 +               if (IS_ERR(page)) {
 321 +                       err = PTR_ERR(page);
 322 +                       goto done;
 323 +               }
 324
 325                 memcpy(buf, page_address(page) + offset, cpylen);
 326                 page_cache_release(page);
 327 @@ -136,7 +156,10 @@
 328                 offset = 0;
 329                 index++;
 330         }
 331 -       return 0;
 332 +
 333 +done:
 334 +       read_unlock(&dev->bdev_mutex);
 335 +       return err;
 336  }
 337
 338
 339 @@ -188,12 +211,22 @@
 340                 size_t *retlen, const u_char *buf)
 341  {
 342         struct block2mtd_dev *dev = mtd->priv;
 343 -       int err;
 344 +       int err = 0;
 345 +
 346 +       read_lock(&dev->bdev_mutex);
 347 +       if (!dev->blkdev) {
 348 +               err = -EINVAL;
 349 +               goto done;
 350 +       }
 351
 352         if (!len)
 353 -               return 0;
 354 -       if (to >= mtd->size)
 355 -               return -ENOSPC;
 356 +               goto done;
 357 +
 358 +       if (to >= mtd->size) {
 359 +               err = -ENOSPC;
 360 +               goto done;
 361 +       }
 362 +
 363         if (to + len > mtd->size)
 364                 len = mtd->size - to;
 365
 366 @@ -202,6 +235,9 @@
 367         mutex_unlock(&dev->write_mutex);
 368         if (err > 0)
 369                 err = 0;
 370 +
 371 +done:
 372 +       read_unlock(&dev->bdev_mutex);
 373         return err;
 374  }
 375
 376 @@ -210,7 +246,12 @@
 377  static void block2mtd_sync(struct mtd_info *mtd)
 378  {
 379         struct block2mtd_dev *dev = mtd->priv;
 380 -       sync_blockdev(dev->blkdev);
 381 +
 382 +       read_lock(&dev->bdev_mutex);
 383 +       if (dev->blkdev)
 384 +               sync_blockdev(dev->blkdev);
 385 +       read_unlock(&dev->bdev_mutex);
 386 +
 387         return;
 388  }
 389
 390 @@ -231,31 +272,22 @@
 391         kfree(dev);
 392  }
 393
 394 -
 395 -/* FIXME: ensure that mtd->size % erase_size == 0 */
 396 -static struct block2mtd_dev *add_device(char *devname, int erase_size, const char *mtdname)
 397 +static int _open_bdev(struct block2mtd_dev *dev)
 398  {
 399         struct block_device *bdev;
 400         struct block2mtd_dev *dev;
 401         struct mtd_partition *part;
 402         char *name;
 403
 404 -       if (!devname)
 405 -               return NULL;
 406 -
 407 -       dev = kzalloc(sizeof(struct block2mtd_dev), GFP_KERNEL);
 408 -       if (!dev)
 409 -               return NULL;
 410 -
 411         /* Get a handle on the device */
 412 -       bdev = open_bdev_excl(devname, O_RDWR, NULL);
 413 +       bdev = open_bdev_excl(dev->devname, O_RDWR, NULL);
 414  #ifndef MODULE
 415         if (IS_ERR(bdev)) {
 416
 417                 /* We might not have rootfs mounted at this point. Try
 418                    to resolve the device name by other means. */
 419
 420 -               dev_t devt = name_to_dev_t(devname);
 421 +               dev_t devt = name_to_dev_t(dev->devname);
 422                 if (devt) {
 423                         bdev = open_by_devnum(devt, FMODE_WRITE | FMODE_READ);
 424                 }
 425 @@ -263,17 +295,96 @@
 426  #endif
 427
 428         if (IS_ERR(bdev)) {
 429 -               ERROR("error: cannot open device %s", devname);
 430 -               goto devinit_err;
 431 +               ERROR("error: cannot open device %s", dev->devname);
 432 +               return 1;
 433         }
 434         dev->blkdev = bdev;
 435
 436         if (MAJOR(bdev->bd_dev) == MTD_BLOCK_MAJOR) {
 437                 ERROR("attempting to use an MTD device as a block device");
 438 -               goto devinit_err;
 439 +               return 1;
 440         }
 441
 442 +       return 0;
 443 +}
 444 +
 445 +static void _close_bdev(struct block2mtd_dev *dev)
 446 +{
 447 +       struct block_device *bdev;
 448 +
 449 +       if (!dev->blkdev)
 450 +               return;
 451 +
 452 +       bdev = dev->blkdev;
 453 +       invalidate_mapping_pages(dev->blkdev->bd_inode->i_mapping, 0, -1);
 454 +       close_bdev_excl(dev->blkdev);
 455 +       dev->blkdev = NULL;
 456 +}
 457 +
 458 +static void block2mtd_free_device(struct block2mtd_dev *dev)
 459 +{
 460 +       if (!dev)
 461 +               return;
 462 +
 463 +       kfree(dev->mtd.name);
 464 +       _close_bdev(dev);
 465 +       kfree(dev);
 466 +}
 467 +
 468 +
 469 +static int block2mtd_refresh(struct mtd_info *mtd)
 470 +{
 471 +       struct block2mtd_dev *dev = mtd->priv;
 472 +       struct block_device *bdev;
 473 +       dev_t devt;
 474 +       int err = 0;
 475 +
 476 +       /* no other mtd function can run at this point */
 477 +       write_lock(&dev->bdev_mutex);
 478 +
 479 +       /* get the device number for the whole disk */
 480 +       devt = MKDEV(MAJOR(dev->blkdev->bd_dev), 0);
 481 +
 482 +       /* close the old block device */
 483 +       _close_bdev(dev);
 484 +
 485 +       /* open the whole disk, issue a partition rescan, then */
 486 +       bdev = open_by_devnum(devt, FMODE_WRITE | FMODE_READ);
 487 +       if (!bdev || !bdev->bd_disk)
 488 +               err = -EINVAL;
 489 +       else {
 490 +               err = rescan_partitions(bdev->bd_disk, bdev);
 491 +       }
 492 +       if (bdev)
 493 +               close_bdev_excl(bdev);
 494 +
 495 +       /* try to open the partition block device again */
 496 +       _open_bdev(dev);
 497 +       write_unlock(&dev->bdev_mutex);
 498 +
 499 +       return err;
 500 +}
 501 +
 502 +/* FIXME: ensure that mtd->size % erase_size == 0 */
 503 +static struct block2mtd_dev *add_device(char *devname, int erase_size, char *mtdname)
 504 +{
 505 +       struct block2mtd_dev *dev;
 506 +       struct mtd_partition *part;
 507 +
 508 +       if (!devname)
 509 +               return NULL;
 510 +
 511 +       dev = kzalloc(sizeof(struct block2mtd_dev) + strlen(devname) + 1, GFP_KERNEL);
 512 +       if (!dev)
 513 +               return NULL;
 514 +
 515 +       strcpy(dev->devname, devname);
 516 +
 517 +       if (_open_bdev(dev))
 518 +               goto devinit_err;
 519 +
 520         mutex_init(&dev->write_mutex);
 521 +       rwlock_init(&dev->bdev_mutex);
 522
 523         if (!mtdname)
 524                 mtdname = devname;
 525 @@ -297,6 +408,7 @@
 526         dev->mtd.read = block2mtd_read;
 527         dev->mtd.priv = dev;
 528         dev->mtd.owner = THIS_MODULE;
 529 +       dev->mtd.refresh_device = block2mtd_refresh;
 530
 531         part = kzalloc(sizeof(struct mtd_partition), GFP_KERNEL);
 532         part->name = dev->mtd.name;
 533 --- a/drivers/mtd/mtdchar.c
 534 +++ b/drivers/mtd/mtdchar.c
 535 @@ -16,6 +16,7 @@
 536
 537  #include <linux/mtd/mtd.h>
 538  #include <linux/mtd/compatmac.h>
 539 +#include <linux/mtd/partitions.h>
 540
 541  #include <asm/uaccess.h>
 542
 543 @@ -771,6 +772,13 @@
 544                 file->f_pos = 0;
 545                 break;
 546         }
 547 +#ifdef CONFIG_MTD_PARTITIONS
 548 +       case MTDREFRESH:
 549 +       {
 550 +               ret = refresh_mtd_partitions(mtd);
 551 +               break;
 552 +       }
 553 +#endif
 554
 555         default:
 556                 ret = -ENOTTY;
 557 --- a/include/linux/mtd/mtd.h
 558 +++ b/include/linux/mtd/mtd.h
 559 @@ -96,6 +96,7 @@
 560         uint8_t         *oobbuf;
 561  };
 562
 563 +struct mtd_info;
 564  struct mtd_info {
 565         u_char type;
 566         u_int32_t flags;
 567 @@ -211,6 +212,9 @@
 568         struct module *owner;
 569         int usecount;
 570
 571 +       int (*refresh_device)(struct mtd_info *mtd);
 572 +       struct mtd_info *split;
 573 +
 574         /* If the driver is something smart, like UBI, it may need to maintain
 575          * its own reference counting. The below functions are only for driver.
 576          * The driver may register its callbacks. These callbacks are not
 577 --- a/include/linux/mtd/partitions.h
 578 +++ b/include/linux/mtd/partitions.h
 579 @@ -34,6 +34,7 @@
 580   * erasesize aligned (e.g. use MTDPART_OFS_NEXTBLK).
 581   */
 582
 583 +struct mtd_partition;
 584  struct mtd_partition {
 585         char *name;                     /* identifier string */
 586         u_int32_t size;                 /* partition size */
 587 @@ -41,6 +42,7 @@
 588         u_int32_t mask_flags;           /* master MTD flags to mask out for this partition */
 589         struct nand_ecclayout *ecclayout;       /* out of band layout for this partition (NAND only)*/
 590         struct mtd_info **mtdp;         /* pointer to store the MTD object */
 591 +       int (*refresh_partition)(struct mtd_info *);
 592  };
 593
 594  #define MTDPART_OFS_NXTBLK     (-2)
 595 @@ -50,6 +52,7 @@
 596
 597  int add_mtd_partitions(struct mtd_info *, const struct mtd_partition *, int);
 598  int del_mtd_partitions(struct mtd_info *);
 599 +int refresh_mtd_partitions(struct mtd_info *);
 600
 601  /*
 602   * Functions dealing with the various ways of partitioning the space
 603 --- a/include/mtd/mtd-abi.h
 604 +++ b/include/mtd/mtd-abi.h
 605 @@ -93,6 +93,7 @@
 606  #define ECCGETLAYOUT           _IOR('M', 17, struct nand_ecclayout)
 607  #define ECCGETSTATS            _IOR('M', 18, struct mtd_ecc_stats)
 608  #define MTDFILEMODE            _IO('M', 19)
 609 +#define MTDREFRESH             _IO('M', 23)
 610
 611  /*
 612   * Obsolete legacy interface. Keep it in order not to break userspace