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   1 /*
   2  * JFFS2 -- Journalling Flash File System, Version 2.
   3  *
   4  * Copyright (C) 2001-2003 Red Hat, Inc.
   5  *
   6  * Created by David Woodhouse <dwmw2@infradead.org>
   7  *
   8  * For licensing information, see the file 'LICENCE' in this directory.
   9  *
  10  * $Id: scan.c,v 1.125 2005/09/30 13:59:13 dedekind Exp $
  11  *
  12  */
  13 #include <linux/kernel.h>
  14 #include <linux/sched.h>
  15 #include <linux/slab.h>
  16 #include <linux/mtd/mtd.h>
  17 #include <linux/pagemap.h>
  18 #include <linux/crc32.h>
  19 #include <linux/compiler.h>
  20 #include "nodelist.h"
  21 #include "summary.h"
  22 #include "debug.h"
  23
  24 #define DEFAULT_EMPTY_SCAN_SIZE 1024
  25
  26 #define noisy_printk(noise, args...) do { \
  27         if (*(noise)) { \
  28                 printk(KERN_NOTICE args); \
  29                  (*(noise))--; \
  30                  if (!(*(noise))) { \
  31                          printk(KERN_NOTICE "Further such events for this erase block will not be printed\n"); \
  32                  } \
  33         } \
  34 } while(0)
  35
  36 static uint32_t pseudo_random;
  37
  38 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
  39                                   unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s);
  40
  41 /* These helper functions _must_ increase ofs and also do the dirty/used space accounting.
  42  * Returning an error will abort the mount - bad checksums etc. should just mark the space
  43  * as dirty.
  44  */
  45 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
  46                                  struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s);
  47 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
  48                                  struct jffs2_raw_dirent *rd, uint32_t ofs, struct jffs2_summary *s);
  49
  50 static inline int min_free(struct jffs2_sb_info *c)
  51 {
  52         uint32_t min = 2 * sizeof(struct jffs2_raw_inode);
  53 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
  54         if (!jffs2_can_mark_obsolete(c) && min < c->wbuf_pagesize)
  55                 return c->wbuf_pagesize;
  56 #endif
  57         return min;
  58
  59 }
  60
  61 static inline uint32_t EMPTY_SCAN_SIZE(uint32_t sector_size) {
  62         if (sector_size < DEFAULT_EMPTY_SCAN_SIZE)
  63                 return sector_size;
  64         else
  65                 return DEFAULT_EMPTY_SCAN_SIZE;
  66 }
  67
  68 int jffs2_scan_medium(struct jffs2_sb_info *c)
  69 {
  70         int i, ret;
  71         uint32_t empty_blocks = 0, bad_blocks = 0;
  72         unsigned char *flashbuf = NULL;
  73         uint32_t buf_size = 0;
  74         struct jffs2_summary *s = NULL; /* summary info collected by the scan process */
  75 #ifndef __ECOS
  76         size_t pointlen;
  77
  78         if (c->mtd->point) {
  79                 ret = c->mtd->point (c->mtd, 0, c->mtd->size, &pointlen, &flashbuf);
  80                 if (!ret && pointlen < c->mtd->size) {
  81                         /* Don't muck about if it won't let us point to the whole flash */
  82                         D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", pointlen));
  83                         c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size);
  84                         flashbuf = NULL;
  85                 }
  86                 if (ret)
  87                         D1(printk(KERN_DEBUG "MTD point failed %d\n", ret));
  88         }
  89 #endif
  90         if (!flashbuf) {
  91                 /* For NAND it's quicker to read a whole eraseblock at a time,
  92                    apparently */
  93                 if (jffs2_cleanmarker_oob(c))
  94                         buf_size = c->sector_size;
  95                 else
  96                         buf_size = PAGE_SIZE;
  97
  98                 /* Respect kmalloc limitations */
  99                 if (buf_size > 128*1024)
 100                         buf_size = 128*1024;
 101
 102                 D1(printk(KERN_DEBUG "Allocating readbuf of %d bytes\n", buf_size));
 103                 flashbuf = kmalloc(buf_size, GFP_KERNEL);
 104                 if (!flashbuf)
 105                         return -ENOMEM;
 106         }
 107
 108         if (jffs2_sum_active()) {
 109                 s = kmalloc(sizeof(struct jffs2_summary), GFP_KERNEL);
 110                 if (!s) {
 111                         JFFS2_WARNING("Can't allocate memory for summary\n");
 112                         return -ENOMEM;
 113                 }
 114                 memset(s, 0, sizeof(struct jffs2_summary));
 115         }
 116
 117         for (i=0; i<c->nr_blocks; i++) {
 118                 struct jffs2_eraseblock *jeb = &c->blocks[i];
 119
 120                 /* reset summary info for next eraseblock scan */
 121                 jffs2_sum_reset_collected(s);
 122
 123                 ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset),
 124                                                 buf_size, s);
 125
 126                 if (ret < 0)
 127                         goto out;
 128
 129                 jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
 130
 131                 /* Now decide which list to put it on */
 132                 switch(ret) {
 133                 case BLK_STATE_ALLFF:
 134                         /*
 135                          * Empty block.   Since we can't be sure it
 136                          * was entirely erased, we just queue it for erase
 137                          * again.  It will be marked as such when the erase
 138                          * is complete.  Meanwhile we still count it as empty
 139                          * for later checks.
 140                          */
 141                         empty_blocks++;
 142                         list_add(&jeb->list, &c->erase_pending_list);
 143                         c->nr_erasing_blocks++;
 144                         break;
 145
 146                 case BLK_STATE_CLEANMARKER:
 147                         /* Only a CLEANMARKER node is valid */
 148                         if (!jeb->dirty_size) {
 149                                 /* It's actually free */
 150                                 list_add(&jeb->list, &c->free_list);
 151                                 c->nr_free_blocks++;
 152                         } else {
 153                                 /* Dirt */
 154                                 D1(printk(KERN_DEBUG "Adding all-dirty block at 0x%08x to erase_pending_list\n", jeb->offset));
 155                                 list_add(&jeb->list, &c->erase_pending_list);
 156                                 c->nr_erasing_blocks++;
 157                         }
 158                         break;
 159
 160                 case BLK_STATE_CLEAN:
 161                         /* Full (or almost full) of clean data. Clean list */
 162                         list_add(&jeb->list, &c->clean_list);
 163                         break;
 164
 165                 case BLK_STATE_PARTDIRTY:
 166                         /* Some data, but not full. Dirty list. */
 167                         /* We want to remember the block with most free space
 168                         and stick it in the 'nextblock' position to start writing to it. */
 169                         if (jeb->free_size > min_free(c) &&
 170                                         (!c->nextblock || c->nextblock->free_size < jeb->free_size)) {
 171                                 /* Better candidate for the next writes to go to */
 172                                 if (c->nextblock) {
 173                                         c->nextblock->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size;
 174                                         c->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size;
 175                                         c->free_size -= c->nextblock->free_size;
 176                                         c->wasted_size -= c->nextblock->wasted_size;
 177                                         c->nextblock->free_size = c->nextblock->wasted_size = 0;
 178                                         if (VERYDIRTY(c, c->nextblock->dirty_size)) {
 179                                                 list_add(&c->nextblock->list, &c->very_dirty_list);
 180                                         } else {
 181                                                 list_add(&c->nextblock->list, &c->dirty_list);
 182                                         }
 183                                         /* deleting summary information of the old nextblock */
 184                                         jffs2_sum_reset_collected(c->summary);
 185                                 }
 186                                 /* update collected summary infromation for the current nextblock */
 187                                 jffs2_sum_move_collected(c, s);
 188                                 D1(printk(KERN_DEBUG "jffs2_scan_medium(): new nextblock = 0x%08x\n", jeb->offset));
 189                                 c->nextblock = jeb;
 190                         } else {
 191                                 jeb->dirty_size += jeb->free_size + jeb->wasted_size;
 192                                 c->dirty_size += jeb->free_size + jeb->wasted_size;
 193                                 c->free_size -= jeb->free_size;
 194                                 c->wasted_size -= jeb->wasted_size;
 195                                 jeb->free_size = jeb->wasted_size = 0;
 196                                 if (VERYDIRTY(c, jeb->dirty_size)) {
 197                                         list_add(&jeb->list, &c->very_dirty_list);
 198                                 } else {
 199                                         list_add(&jeb->list, &c->dirty_list);
 200                                 }
 201                         }
 202                         break;
 203
 204                 case BLK_STATE_ALLDIRTY:
 205                         /* Nothing valid - not even a clean marker. Needs erasing. */
 206                         /* For now we just put it on the erasing list. We'll start the erases later */
 207                         D1(printk(KERN_NOTICE "JFFS2: Erase block at 0x%08x is not formatted. It will be erased\n", jeb->offset));
 208                         list_add(&jeb->list, &c->erase_pending_list);
 209                         c->nr_erasing_blocks++;
 210                         break;
 211
 212                 case BLK_STATE_BADBLOCK:
 213                         D1(printk(KERN_NOTICE "JFFS2: Block at 0x%08x is bad\n", jeb->offset));
 214                         list_add(&jeb->list, &c->bad_list);
 215                         c->bad_size += c->sector_size;
 216                         c->free_size -= c->sector_size;
 217                         bad_blocks++;
 218                         break;
 219                 default:
 220                         printk(KERN_WARNING "jffs2_scan_medium(): unknown block state\n");
 221                         BUG();
 222                 }
 223         }
 224
 225         if (jffs2_sum_active() && s)
 226                 kfree(s);
 227
 228         /* Nextblock dirty is always seen as wasted, because we cannot recycle it now */
 229         if (c->nextblock && (c->nextblock->dirty_size)) {
 230                 c->nextblock->wasted_size += c->nextblock->dirty_size;
 231                 c->wasted_size += c->nextblock->dirty_size;
 232                 c->dirty_size -= c->nextblock->dirty_size;
 233                 c->nextblock->dirty_size = 0;
 234         }
 235 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
 236         if (!jffs2_can_mark_obsolete(c) && c->wbuf_pagesize && c->nextblock && (c->nextblock->free_size % c->wbuf_pagesize)) {
 237                 /* If we're going to start writing into a block which already
 238                    contains data, and the end of the data isn't page-aligned,
 239                    skip a little and align it. */
 240
 241                 uint32_t skip = c->nextblock->free_size % c->wbuf_pagesize;
 242
 243                 D1(printk(KERN_DEBUG "jffs2_scan_medium(): Skipping %d bytes in nextblock to ensure page alignment\n",
 244                           skip));
 245                 c->nextblock->wasted_size += skip;
 246                 c->wasted_size += skip;
 247
 248                 c->nextblock->free_size -= skip;
 249                 c->free_size -= skip;
 250         }
 251 #endif
 252         if (c->nr_erasing_blocks) {
 253                 if ( !c->used_size && ((c->nr_free_blocks+empty_blocks+bad_blocks)!= c->nr_blocks || bad_blocks == c->nr_blocks) ) {
 254                         printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n");
 255                         printk(KERN_NOTICE "empty_blocks %d, bad_blocks %d, c->nr_blocks %d\n",empty_blocks,bad_blocks,c->nr_blocks);
 256                         ret = -EIO;
 257                         goto out;
 258                 }
 259                 jffs2_erase_pending_trigger(c);
 260         }
 261         ret = 0;
 262  out:
 263         if (buf_size)
 264                 kfree(flashbuf);
 265 #ifndef __ECOS
 266         else
 267                 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size);
 268 #endif
 269         return ret;
 270 }
 271
 272 int jffs2_fill_scan_buf (struct jffs2_sb_info *c, void *buf,
 273                                 uint32_t ofs, uint32_t len)
 274 {
 275         int ret;
 276         size_t retlen;
 277
 278         ret = jffs2_flash_read(c, ofs, len, &retlen, buf);
 279         if (ret) {
 280                 D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", len, ofs, ret));
 281                 return ret;
 282         }
 283         if (retlen < len) {
 284                 D1(printk(KERN_WARNING "Read at 0x%x gave only 0x%zx bytes\n", ofs, retlen));
 285                 return -EIO;
 286         }
 287         return 0;
 288 }
 289
 290 int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
 291 {
 292         if ((jeb->used_size + jeb->unchecked_size) == PAD(c->cleanmarker_size) && !jeb->dirty_size
 293                 && (!jeb->first_node || !jeb->first_node->next_phys) )
 294                 return BLK_STATE_CLEANMARKER;
 295
 296         /* move blocks with max 4 byte dirty space to cleanlist */
 297         else if (!ISDIRTY(c->sector_size - (jeb->used_size + jeb->unchecked_size))) {
 298                 c->dirty_size -= jeb->dirty_size;
 299                 c->wasted_size += jeb->dirty_size;
 300                 jeb->wasted_size += jeb->dirty_size;
 301                 jeb->dirty_size = 0;
 302                 return BLK_STATE_CLEAN;
 303         } else if (jeb->used_size || jeb->unchecked_size)
 304                 return BLK_STATE_PARTDIRTY;
 305         else
 306                 return BLK_STATE_ALLDIRTY;
 307 }
 308
 309 #ifdef CONFIG_JFFS2_FS_XATTR
 310 static int jffs2_scan_xattr_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 311                                  struct jffs2_raw_xattr *rx, uint32_t ofs,
 312                                  struct jffs2_summary *s)
 313 {
 314         struct jffs2_xattr_datum *xd;
 315         struct jffs2_raw_node_ref *raw;
 316         uint32_t totlen, crc;
 317
 318         crc = crc32(0, rx, sizeof(struct jffs2_raw_xattr) - 4);
 319         if (crc != je32_to_cpu(rx->node_crc)) {
 320                 if (je32_to_cpu(rx->node_crc) != 0xffffffff)
 321                         JFFS2_WARNING("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
 322                                       ofs, je32_to_cpu(rx->node_crc), crc);
 323                 DIRTY_SPACE(je32_to_cpu(rx->totlen));
 324                 return 0;
 325         }
 326
 327         totlen = PAD(sizeof(*rx) + rx->name_len + 1 + je16_to_cpu(rx->value_len));
 328         if (totlen != je32_to_cpu(rx->totlen)) {
 329                 JFFS2_WARNING("node length mismatch at %#08x, read=%u, calc=%u\n",
 330                               ofs, je32_to_cpu(rx->totlen), totlen);
 331                 DIRTY_SPACE(je32_to_cpu(rx->totlen));
 332                 return 0;
 333         }
 334
 335         raw =  jffs2_alloc_raw_node_ref();
 336         if (!raw)
 337                 return -ENOMEM;
 338
 339         xd = jffs2_setup_xattr_datum(c, je32_to_cpu(rx->xid), je32_to_cpu(rx->version));
 340         if (IS_ERR(xd)) {
 341                 jffs2_free_raw_node_ref(raw);
 342                 if (PTR_ERR(xd) == -EEXIST) {
 343                         DIRTY_SPACE(PAD(je32_to_cpu(rx->totlen)));
 344                         return 0;
 345                 }
 346                 return PTR_ERR(xd);
 347         }
 348         xd->xprefix = rx->xprefix;
 349         xd->name_len = rx->name_len;
 350         xd->value_len = je16_to_cpu(rx->value_len);
 351         xd->data_crc = je32_to_cpu(rx->data_crc);
 352         xd->node = raw;
 353
 354         raw->__totlen = totlen;
 355         raw->flash_offset = ofs | REF_PRISTINE;
 356         raw->next_phys = NULL;
 357         raw->next_in_ino = (void *)xd;
 358         if (!jeb->first_node)
 359                 jeb->first_node = raw;
 360         if (jeb->last_node)
 361                 jeb->last_node->next_phys = raw;
 362         jeb->last_node = raw;
 363
 364         USED_SPACE(PAD(je32_to_cpu(rx->totlen)));
 365         if (jffs2_sum_active())
 366                 jffs2_sum_add_xattr_mem(s, rx, ofs - jeb->offset);
 367         dbg_xattr("scaning xdatum at %#08x (xid=%u, version=%u)\n",
 368                   ofs, xd->xid, xd->version);
 369         return 0;
 370 }
 371
 372 static int jffs2_scan_xref_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 373                                 struct jffs2_raw_xref *rr, uint32_t ofs,
 374                                 struct jffs2_summary *s)
 375 {
 376         struct jffs2_xattr_ref *ref;
 377         struct jffs2_raw_node_ref *raw;
 378         uint32_t crc;
 379
 380         crc = crc32(0, rr, sizeof(*rr) - 4);
 381         if (crc != je32_to_cpu(rr->node_crc)) {
 382                 if (je32_to_cpu(rr->node_crc) != 0xffffffff)
 383                         JFFS2_WARNING("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
 384                                       ofs, je32_to_cpu(rr->node_crc), crc);
 385                 DIRTY_SPACE(PAD(je32_to_cpu(rr->totlen)));
 386                 return 0;
 387         }
 388
 389         if (PAD(sizeof(struct jffs2_raw_xref)) != je32_to_cpu(rr->totlen)) {
 390                 JFFS2_WARNING("node length mismatch at %#08x, read=%u, calc=%u\n",
 391                               ofs, je32_to_cpu(rr->totlen),
 392                               PAD(sizeof(struct jffs2_raw_xref)));
 393                 DIRTY_SPACE(je32_to_cpu(rr->totlen));
 394                 return 0;
 395         }
 396
 397         ref = jffs2_alloc_xattr_ref();
 398         if (!ref)
 399                 return -ENOMEM;
 400
 401         raw =  jffs2_alloc_raw_node_ref();
 402         if (!raw) {
 403                 jffs2_free_xattr_ref(ref);
 404                 return -ENOMEM;
 405         }
 406
 407         /* BEFORE jffs2_build_xattr_subsystem() called,
 408          * ref->xid is used to store 32bit xid, xd is not used
 409          * ref->ino is used to store 32bit inode-number, ic is not used
 410          * Thoes variables are declared as union, thus using those
 411          * are exclusive. In a similar way, ref->ilist is temporarily
 412          * used to chain all xattr_ref object. It's re-chained to
 413          * jffs2_inode_cache in jffs2_build_xattr_subsystem() correctly.
 414          */
 415         ref->node = raw;
 416         ref->ino = je32_to_cpu(rr->ino);
 417         ref->xid = je32_to_cpu(rr->xid);
 418         list_add_tail(&ref->ilist, &c->xattr_temp);
 419
 420         raw->__totlen = PAD(je32_to_cpu(rr->totlen));
 421         raw->flash_offset = ofs | REF_PRISTINE;
 422         raw->next_phys = NULL;
 423         raw->next_in_ino = (void *)ref;
 424         if (!jeb->first_node)
 425                 jeb->first_node = raw;
 426         if (jeb->last_node)
 427                 jeb->last_node->next_phys = raw;
 428         jeb->last_node = raw;
 429
 430         USED_SPACE(PAD(je32_to_cpu(rr->totlen)));
 431         if (jffs2_sum_active())
 432                 jffs2_sum_add_xref_mem(s, rr, ofs - jeb->offset);
 433         dbg_xattr("scan xref at %#08x (xid=%u, ino=%u)\n",
 434                   ofs, ref->xid, ref->ino);
 435         return 0;
 436 }
 437 #endif
 438
 439 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 440                                 unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s) {
 441         struct jffs2_unknown_node *node;
 442         struct jffs2_unknown_node crcnode;
 443         struct jffs2_sum_marker *sm;
 444         uint32_t ofs, prevofs;
 445         uint32_t hdr_crc, buf_ofs, buf_len;
 446         int err;
 447         int noise = 0;
 448
 449
 450 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
 451         int cleanmarkerfound = 0;
 452 #endif
 453
 454         ofs = jeb->offset;
 455         prevofs = jeb->offset - 1;
 456
 457         D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs));
 458
 459 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
 460         if (jffs2_cleanmarker_oob(c)) {
 461                 int ret = jffs2_check_nand_cleanmarker(c, jeb);
 462                 D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n",ret));
 463                 /* Even if it's not found, we still scan to see
 464                    if the block is empty. We use this information
 465                    to decide whether to erase it or not. */
 466                 switch (ret) {
 467                 case 0:         cleanmarkerfound = 1; break;
 468                 case 1:         break;
 469                 case 2:         return BLK_STATE_BADBLOCK;
 470                 case 3:         return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */
 471                 default:        return ret;
 472                 }
 473         }
 474 #endif
 475
 476         if (jffs2_sum_active()) {
 477                 sm = kmalloc(sizeof(struct jffs2_sum_marker), GFP_KERNEL);
 478                 if (!sm) {
 479                         return -ENOMEM;
 480                 }
 481
 482                 err = jffs2_fill_scan_buf(c, (unsigned char *) sm, jeb->offset + c->sector_size -
 483                                         sizeof(struct jffs2_sum_marker), sizeof(struct jffs2_sum_marker));
 484                 if (err) {
 485                         kfree(sm);
 486                         return err;
 487                 }
 488
 489                 if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC ) {
 490                         err = jffs2_sum_scan_sumnode(c, jeb, je32_to_cpu(sm->offset), &pseudo_random);
 491                         if (err) {
 492                                 kfree(sm);
 493                                 return err;
 494                         }
 495                 }
 496
 497                 kfree(sm);
 498
 499                 ofs = jeb->offset;
 500                 prevofs = jeb->offset - 1;
 501         }
 502
 503         buf_ofs = jeb->offset;
 504
 505         if (!buf_size) {
 506                 buf_len = c->sector_size;
 507
 508                 if (jffs2_sum_active()) {
 509                         /* must reread because of summary test */
 510                         err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
 511                         if (err)
 512                                 return err;
 513                 }
 514
 515         } else {
 516                 buf_len = EMPTY_SCAN_SIZE(c->sector_size);
 517                 err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
 518                 if (err)
 519                         return err;
 520         }
 521
 522         /* We temporarily use 'ofs' as a pointer into the buffer/jeb */
 523         ofs = 0;
 524
 525         /* Scan only 4KiB of 0xFF before declaring it's empty */
 526         while(ofs < EMPTY_SCAN_SIZE(c->sector_size) && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF)
 527                 ofs += 4;
 528
 529         if (ofs == EMPTY_SCAN_SIZE(c->sector_size)) {
 530 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
 531                 if (jffs2_cleanmarker_oob(c)) {
 532                         /* scan oob, take care of cleanmarker */
 533                         int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound);
 534                         D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret));
 535                         switch (ret) {
 536                         case 0:         return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF;
 537                         case 1:         return BLK_STATE_ALLDIRTY;
 538                         default:        return ret;
 539                         }
 540                 }
 541 #endif
 542                 D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset));
 543                 if (c->cleanmarker_size == 0)
 544                         return BLK_STATE_CLEANMARKER;   /* don't bother with re-erase */
 545                 else
 546                         return BLK_STATE_ALLFF; /* OK to erase if all blocks are like this */
 547         }
 548         if (ofs) {
 549                 D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset,
 550                           jeb->offset + ofs));
 551                 DIRTY_SPACE(ofs);
 552         }
 553
 554         /* Now ofs is a complete physical flash offset as it always was... */
 555         ofs += jeb->offset;
 556
 557         noise = 10;
 558
 559         dbg_summary("no summary found in jeb 0x%08x. Apply original scan.\n",jeb->offset);
 560
 561 scan_more:
 562         while(ofs < jeb->offset + c->sector_size) {
 563
 564                 jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
 565
 566                 cond_resched();
 567
 568                 if (ofs & 3) {
 569                         printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs);
 570                         ofs = PAD(ofs);
 571                         continue;
 572                 }
 573                 if (ofs == prevofs) {
 574                         printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs);
 575                         DIRTY_SPACE(4);
 576                         ofs += 4;
 577                         continue;
 578                 }
 579                 prevofs = ofs;
 580
 581                 if (jeb->offset + c->sector_size < ofs + sizeof(*node)) {
 582                         D1(printk(KERN_DEBUG "Fewer than %zd bytes left to end of block. (%x+%x<%x+%zx) Not reading\n", sizeof(struct jffs2_unknown_node),
 583                                   jeb->offset, c->sector_size, ofs, sizeof(*node)));
 584                         DIRTY_SPACE((jeb->offset + c->sector_size)-ofs);
 585                         break;
 586                 }
 587
 588                 if (buf_ofs + buf_len < ofs + sizeof(*node)) {
 589                         buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
 590                         D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n",
 591                                   sizeof(struct jffs2_unknown_node), buf_len, ofs));
 592                         err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
 593                         if (err)
 594                                 return err;
 595                         buf_ofs = ofs;
 596                 }
 597
 598                 node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs];
 599
 600                 if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) {
 601                         uint32_t inbuf_ofs;
 602                         uint32_t empty_start;
 603
 604                         empty_start = ofs;
 605                         ofs += 4;
 606
 607                         D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs));
 608                 more_empty:
 609                         inbuf_ofs = ofs - buf_ofs;
 610                         while (inbuf_ofs < buf_len) {
 611                                 if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff) {
 612                                         printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n",
 613                                                empty_start, ofs);
 614                                         DIRTY_SPACE(ofs-empty_start);
 615                                         goto scan_more;
 616                                 }
 617
 618                                 inbuf_ofs+=4;
 619                                 ofs += 4;
 620                         }
 621                         /* Ran off end. */
 622                         D1(printk(KERN_DEBUG "Empty flash to end of buffer at 0x%08x\n", ofs));
 623
 624                         /* If we're only checking the beginning of a block with a cleanmarker,
 625                            bail now */
 626                         if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) &&
 627                             c->cleanmarker_size && !jeb->dirty_size && !jeb->first_node->next_phys) {
 628                                 D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE(c->sector_size)));
 629                                 return BLK_STATE_CLEANMARKER;
 630                         }
 631
 632                         /* See how much more there is to read in this eraseblock... */
 633                         buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
 634                         if (!buf_len) {
 635                                 /* No more to read. Break out of main loop without marking
 636                                    this range of empty space as dirty (because it's not) */
 637                                 D1(printk(KERN_DEBUG "Empty flash at %08x runs to end of block. Treating as free_space\n",
 638                                           empty_start));
 639                                 break;
 640                         }
 641                         D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs));
 642                         err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
 643                         if (err)
 644                                 return err;
 645                         buf_ofs = ofs;
 646                         goto more_empty;
 647                 }
 648
 649                 if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) {
 650                         printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs);
 651                         DIRTY_SPACE(4);
 652                         ofs += 4;
 653                         continue;
 654                 }
 655                 if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) {
 656                         D1(printk(KERN_DEBUG "Dirty bitmask at 0x%08x\n", ofs));
 657                         DIRTY_SPACE(4);
 658                         ofs += 4;
 659                         continue;
 660                 }
 661                 if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) {
 662                         printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs);
 663                         printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n");
 664                         DIRTY_SPACE(4);
 665                         ofs += 4;
 666                         continue;
 667                 }
 668                 if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) {
 669                         /* OK. We're out of possibilities. Whinge and move on */
 670                         noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n",
 671                                      JFFS2_MAGIC_BITMASK, ofs,
 672                                      je16_to_cpu(node->magic));
 673                         DIRTY_SPACE(4);
 674                         ofs += 4;
 675                         continue;
 676                 }
 677                 /* We seem to have a node of sorts. Check the CRC */
 678                 crcnode.magic = node->magic;
 679                 crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE);
 680                 crcnode.totlen = node->totlen;
 681                 hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4);
 682
 683                 if (hdr_crc != je32_to_cpu(node->hdr_crc)) {
 684                         noisy_printk(&noise, "jffs2_scan_eraseblock(): Node at 0x%08x {0x%04x, 0x%04x, 0x%08x) has invalid CRC 0x%08x (calculated 0x%08x)\n",
 685                                      ofs, je16_to_cpu(node->magic),
 686                                      je16_to_cpu(node->nodetype),
 687                                      je32_to_cpu(node->totlen),
 688                                      je32_to_cpu(node->hdr_crc),
 689                                      hdr_crc);
 690                         DIRTY_SPACE(4);
 691                         ofs += 4;
 692                         continue;
 693                 }
 694
 695                 if (ofs + je32_to_cpu(node->totlen) >
 696                     jeb->offset + c->sector_size) {
 697                         /* Eep. Node goes over the end of the erase block. */
 698                         printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n",
 699                                ofs, je32_to_cpu(node->totlen));
 700                         printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n");
 701                         DIRTY_SPACE(4);
 702                         ofs += 4;
 703                         continue;
 704                 }
 705
 706                 if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) {
 707                         /* Wheee. This is an obsoleted node */
 708                         D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs));
 709                         DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
 710                         ofs += PAD(je32_to_cpu(node->totlen));
 711                         continue;
 712                 }
 713
 714                 switch(je16_to_cpu(node->nodetype)) {
 715                 case JFFS2_NODETYPE_INODE:
 716                         if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) {
 717                                 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
 718                                 D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n",
 719                                           sizeof(struct jffs2_raw_inode), buf_len, ofs));
 720                                 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
 721                                 if (err)
 722                                         return err;
 723                                 buf_ofs = ofs;
 724                                 node = (void *)buf;
 725                         }
 726                         err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs, s);
 727                         if (err) return err;
 728                         ofs += PAD(je32_to_cpu(node->totlen));
 729                         break;
 730
 731                 case JFFS2_NODETYPE_DIRENT:
 732                         if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
 733                                 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
 734                                 D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n",
 735                                           je32_to_cpu(node->totlen), buf_len, ofs));
 736                                 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
 737                                 if (err)
 738                                         return err;
 739                                 buf_ofs = ofs;
 740                                 node = (void *)buf;
 741                         }
 742                         err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs, s);
 743                         if (err) return err;
 744                         ofs += PAD(je32_to_cpu(node->totlen));
 745                         break;
 746
 747 #ifdef CONFIG_JFFS2_FS_XATTR
 748                 case JFFS2_NODETYPE_XATTR:
 749                         if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
 750                                 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
 751                                 D1(printk(KERN_DEBUG "Fewer than %d bytes (xattr node)"
 752                                           " left to end of buf. Reading 0x%x at 0x%08x\n",
 753                                           je32_to_cpu(node->totlen), buf_len, ofs));
 754                                 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
 755                                 if (err)
 756                                         return err;
 757                                 buf_ofs = ofs;
 758                                 node = (void *)buf;
 759                         }
 760                         err = jffs2_scan_xattr_node(c, jeb, (void *)node, ofs, s);
 761                         if (err)
 762                                 return err;
 763                         ofs += PAD(je32_to_cpu(node->totlen));
 764                         break;
 765                 case JFFS2_NODETYPE_XREF:
 766                         if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
 767                                 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
 768                                 D1(printk(KERN_DEBUG "Fewer than %d bytes (xref node)"
 769                                           " left to end of buf. Reading 0x%x at 0x%08x\n",
 770                                           je32_to_cpu(node->totlen), buf_len, ofs));
 771                                 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
 772                                 if (err)
 773                                         return err;
 774                                 buf_ofs = ofs;
 775                                 node = (void *)buf;
 776                         }
 777                         err = jffs2_scan_xref_node(c, jeb, (void *)node, ofs, s);
 778                         if (err)
 779                                 return err;
 780                         ofs += PAD(je32_to_cpu(node->totlen));
 781                         break;
 782 #endif  /* CONFIG_JFFS2_FS_XATTR */
 783
 784                 case JFFS2_NODETYPE_CLEANMARKER:
 785                         D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs));
 786                         if (je32_to_cpu(node->totlen) != c->cleanmarker_size) {
 787                                 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n",
 788                                        ofs, je32_to_cpu(node->totlen), c->cleanmarker_size);
 789                                 DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
 790                                 ofs += PAD(sizeof(struct jffs2_unknown_node));
 791                         } else if (jeb->first_node) {
 792                                 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset);
 793                                 DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
 794                                 ofs += PAD(sizeof(struct jffs2_unknown_node));
 795                         } else {
 796                                 struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref();
 797                                 if (!marker_ref) {
 798                                         printk(KERN_NOTICE "Failed to allocate node ref for clean marker\n");
 799                                         return -ENOMEM;
 800                                 }
 801                                 marker_ref->next_in_ino = NULL;
 802                                 marker_ref->next_phys = NULL;
 803                                 marker_ref->flash_offset = ofs | REF_NORMAL;
 804                                 marker_ref->__totlen = c->cleanmarker_size;
 805                                 jeb->first_node = jeb->last_node = marker_ref;
 806
 807                                 USED_SPACE(PAD(c->cleanmarker_size));
 808                                 ofs += PAD(c->cleanmarker_size);
 809                         }
 810                         break;
 811
 812                 case JFFS2_NODETYPE_PADDING:
 813                         if (jffs2_sum_active())
 814                                 jffs2_sum_add_padding_mem(s, je32_to_cpu(node->totlen));
 815                         DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
 816                         ofs += PAD(je32_to_cpu(node->totlen));
 817                         break;
 818
 819                 default:
 820                         switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) {
 821                         case JFFS2_FEATURE_ROCOMPAT:
 822                                 printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
 823                                 c->flags |= JFFS2_SB_FLAG_RO;
 824                                 if (!(jffs2_is_readonly(c)))
 825                                         return -EROFS;
 826                                 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
 827                                 ofs += PAD(je32_to_cpu(node->totlen));
 828                                 break;
 829
 830                         case JFFS2_FEATURE_INCOMPAT:
 831                                 printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
 832                                 return -EINVAL;
 833
 834                         case JFFS2_FEATURE_RWCOMPAT_DELETE:
 835                                 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
 836                                 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
 837                                 ofs += PAD(je32_to_cpu(node->totlen));
 838                                 break;
 839
 840                         case JFFS2_FEATURE_RWCOMPAT_COPY:
 841                                 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
 842                                 USED_SPACE(PAD(je32_to_cpu(node->totlen)));
 843                                 ofs += PAD(je32_to_cpu(node->totlen));
 844                                 break;
 845                         }
 846                 }
 847         }
 848
 849         if (jffs2_sum_active()) {
 850                 if (PAD(s->sum_size + JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size) {
 851                         dbg_summary("There is not enough space for "
 852                                 "summary information, disabling for this jeb!\n");
 853                         jffs2_sum_disable_collecting(s);
 854                 }
 855         }
 856
 857         D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x\n", jeb->offset,
 858                   jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size));
 859
 860         /* mark_node_obsolete can add to wasted !! */
 861         if (jeb->wasted_size) {
 862                 jeb->dirty_size += jeb->wasted_size;
 863                 c->dirty_size += jeb->wasted_size;
 864                 c->wasted_size -= jeb->wasted_size;
 865                 jeb->wasted_size = 0;
 866         }
 867
 868         return jffs2_scan_classify_jeb(c, jeb);
 869 }
 870
 871 struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
 872 {
 873         struct jffs2_inode_cache *ic;
 874
 875         ic = jffs2_get_ino_cache(c, ino);
 876         if (ic)
 877                 return ic;
 878
 879         if (ino > c->highest_ino)
 880                 c->highest_ino = ino;
 881
 882         ic = jffs2_alloc_inode_cache();
 883         if (!ic) {
 884                 printk(KERN_NOTICE "jffs2_scan_make_inode_cache(): allocation of inode cache failed\n");
 885                 return NULL;
 886         }
 887         memset(ic, 0, sizeof(*ic));
 888
 889         ic->ino = ino;
 890         ic->nodes = (void *)ic;
 891         init_xattr_inode_cache(ic);
 892         jffs2_add_ino_cache(c, ic);
 893         if (ino == 1)
 894                 ic->nlink = 1;
 895         return ic;
 896 }
 897
 898 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 899                                  struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s)
 900 {
 901         struct jffs2_raw_node_ref *raw;
 902         struct jffs2_inode_cache *ic;
 903         uint32_t ino = je32_to_cpu(ri->ino);
 904
 905         D1(printk(KERN_DEBUG "jffs2_scan_inode_node(): Node at 0x%08x\n", ofs));
 906
 907         /* We do very little here now. Just check the ino# to which we should attribute
 908            this node; we can do all the CRC checking etc. later. There's a tradeoff here --
 909            we used to scan the flash once only, reading everything we want from it into
 910            memory, then building all our in-core data structures and freeing the extra
 911            information. Now we allow the first part of the mount to complete a lot quicker,
 912            but we have to go _back_ to the flash in order to finish the CRC checking, etc.
 913            Which means that the _full_ amount of time to get to proper write mode with GC
 914            operational may actually be _longer_ than before. Sucks to be me. */
 915
 916         raw = jffs2_alloc_raw_node_ref();
 917         if (!raw) {
 918                 printk(KERN_NOTICE "jffs2_scan_inode_node(): allocation of node reference failed\n");
 919                 return -ENOMEM;
 920         }
 921
 922         ic = jffs2_get_ino_cache(c, ino);
 923         if (!ic) {
 924                 /* Inocache get failed. Either we read a bogus ino# or it's just genuinely the
 925                    first node we found for this inode. Do a CRC check to protect against the former
 926                    case */
 927                 uint32_t crc = crc32(0, ri, sizeof(*ri)-8);
 928
 929                 if (crc != je32_to_cpu(ri->node_crc)) {
 930                         printk(KERN_NOTICE "jffs2_scan_inode_node(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
 931                                ofs, je32_to_cpu(ri->node_crc), crc);
 932                         /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */
 933                         DIRTY_SPACE(PAD(je32_to_cpu(ri->totlen)));
 934                         jffs2_free_raw_node_ref(raw);
 935                         return 0;
 936                 }
 937                 ic = jffs2_scan_make_ino_cache(c, ino);
 938                 if (!ic) {
 939                         jffs2_free_raw_node_ref(raw);
 940                         return -ENOMEM;
 941                 }
 942         }
 943
 944         /* Wheee. It worked */
 945
 946         raw->flash_offset = ofs | REF_UNCHECKED;
 947         raw->__totlen = PAD(je32_to_cpu(ri->totlen));
 948         raw->next_phys = NULL;
 949         raw->next_in_ino = ic->nodes;
 950
 951         ic->nodes = raw;
 952         if (!jeb->first_node)
 953                 jeb->first_node = raw;
 954         if (jeb->last_node)
 955                 jeb->last_node->next_phys = raw;
 956         jeb->last_node = raw;
 957
 958         D1(printk(KERN_DEBUG "Node is ino #%u, version %d. Range 0x%x-0x%x\n",
 959                   je32_to_cpu(ri->ino), je32_to_cpu(ri->version),
 960                   je32_to_cpu(ri->offset),
 961                   je32_to_cpu(ri->offset)+je32_to_cpu(ri->dsize)));
 962
 963         pseudo_random += je32_to_cpu(ri->version);
 964
 965         UNCHECKED_SPACE(PAD(je32_to_cpu(ri->totlen)));
 966
 967         if (jffs2_sum_active()) {
 968                 jffs2_sum_add_inode_mem(s, ri, ofs - jeb->offset);
 969         }
 970
 971         return 0;
 972 }
 973
 974 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 975                                   struct jffs2_raw_dirent *rd, uint32_t ofs, struct jffs2_summary *s)
 976 {
 977         struct jffs2_raw_node_ref *raw;
 978         struct jffs2_full_dirent *fd;
 979         struct jffs2_inode_cache *ic;
 980         uint32_t crc;
 981
 982         D1(printk(KERN_DEBUG "jffs2_scan_dirent_node(): Node at 0x%08x\n", ofs));
 983
 984         /* We don't get here unless the node is still valid, so we don't have to
 985            mask in the ACCURATE bit any more. */
 986         crc = crc32(0, rd, sizeof(*rd)-8);
 987
 988         if (crc != je32_to_cpu(rd->node_crc)) {
 989                 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Node CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
 990                        ofs, je32_to_cpu(rd->node_crc), crc);
 991                 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */
 992                 DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen)));
 993                 return 0;
 994         }
 995
 996         pseudo_random += je32_to_cpu(rd->version);
 997
 998         fd = jffs2_alloc_full_dirent(rd->nsize+1);
 999         if (!fd) {
1000                 return -ENOMEM;
1001         }
1002         memcpy(&fd->name, rd->name, rd->nsize);
1003         fd->name[rd->nsize] = 0;
1004
1005         crc = crc32(0, fd->name, rd->nsize);
1006         if (crc != je32_to_cpu(rd->name_crc)) {
1007                 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
1008                        ofs, je32_to_cpu(rd->name_crc), crc);
1009                 D1(printk(KERN_NOTICE "Name for which CRC failed is (now) '%s', ino #%d\n", fd->name, je32_to_cpu(rd->ino)));
1010                 jffs2_free_full_dirent(fd);
1011                 /* FIXME: Why do we believe totlen? */
1012                 /* We believe totlen because the CRC on the node _header_ was OK, just the name failed. */
1013                 DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen)));
1014                 return 0;
1015         }
1016         raw = jffs2_alloc_raw_node_ref();
1017         if (!raw) {
1018                 jffs2_free_full_dirent(fd);
1019                 printk(KERN_NOTICE "jffs2_scan_dirent_node(): allocation of node reference failed\n");
1020                 return -ENOMEM;
1021         }
1022         ic = jffs2_scan_make_ino_cache(c, je32_to_cpu(rd->pino));
1023         if (!ic) {
1024                 jffs2_free_full_dirent(fd);
1025                 jffs2_free_raw_node_ref(raw);
1026                 return -ENOMEM;
1027         }
1028
1029         raw->__totlen = PAD(je32_to_cpu(rd->totlen));
1030         raw->flash_offset = ofs | REF_PRISTINE;
1031         raw->next_phys = NULL;
1032         raw->next_in_ino = ic->nodes;
1033         ic->nodes = raw;
1034         if (!jeb->first_node)
1035                 jeb->first_node = raw;
1036         if (jeb->last_node)
1037                 jeb->last_node->next_phys = raw;
1038         jeb->last_node = raw;
1039
1040         fd->raw = raw;
1041         fd->next = NULL;
1042         fd->version = je32_to_cpu(rd->version);
1043         fd->ino = je32_to_cpu(rd->ino);
1044         fd->nhash = full_name_hash(fd->name, rd->nsize);
1045         fd->type = rd->type;
1046         USED_SPACE(PAD(je32_to_cpu(rd->totlen)));
1047         jffs2_add_fd_to_list(c, fd, &ic->scan_dents);
1048
1049         if (jffs2_sum_active()) {
1050                 jffs2_sum_add_dirent_mem(s, rd, ofs - jeb->offset);
1051         }
1052
1053         return 0;
1054 }
1055
1056 static int count_list(struct list_head *l)
1057 {
1058         uint32_t count = 0;
1059         struct list_head *tmp;
1060
1061         list_for_each(tmp, l) {
1062                 count++;
1063         }
1064         return count;
1065 }
1066
1067 /* Note: This breaks if list_empty(head). I don't care. You
1068    might, if you copy this code and use it elsewhere :) */
1069 static void rotate_list(struct list_head *head, uint32_t count)
1070 {
1071         struct list_head *n = head->next;
1072
1073         list_del(head);
1074         while(count--) {
1075                 n = n->next;
1076         }
1077         list_add(head, n);
1078 }
1079
1080 void jffs2_rotate_lists(struct jffs2_sb_info *c)
1081 {
1082         uint32_t x;
1083         uint32_t rotateby;
1084
1085         x = count_list(&c->clean_list);
1086         if (x) {
1087                 rotateby = pseudo_random % x;
1088                 rotate_list((&c->clean_list), rotateby);
1089         }
1090
1091         x = count_list(&c->very_dirty_list);
1092         if (x) {
1093                 rotateby = pseudo_random % x;
1094                 rotate_list((&c->very_dirty_list), rotateby);
1095         }
1096
1097         x = count_list(&c->dirty_list);
1098         if (x) {
1099                 rotateby = pseudo_random % x;
1100                 rotate_list((&c->dirty_list), rotateby);
1101         }
1102
1103         x = count_list(&c->erasable_list);
1104         if (x) {
1105                 rotateby = pseudo_random % x;
1106                 rotate_list((&c->erasable_list), rotateby);
1107         }
1108
1109         if (c->nr_erasing_blocks) {
1110                 rotateby = pseudo_random % c->nr_erasing_blocks;
1111                 rotate_list((&c->erase_pending_list), rotateby);
1112         }
1113
1114         if (c->nr_free_blocks) {
1115                 rotateby = pseudo_random % c->nr_free_blocks;
1116                 rotate_list((&c->free_list), rotateby);
1117         }
1118 }