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 static int file_dirty(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb) 69 { 70 int ret = jffs2_scan_dirty_space(c, jeb, jeb->free_size); 71 if (ret) 72 return ret; 73 /* Turned wasted size into dirty, since we apparently 74 think it's recoverable now. */ 75 jeb->dirty_size += jeb->wasted_size; 76 c->dirty_size += jeb->wasted_size; 77 c->wasted_size -= jeb->wasted_size; 78 jeb->wasted_size = 0; 79 if (VERYDIRTY(c, jeb->dirty_size)) { 80 list_add(&jeb->list, &c->very_dirty_list); 81 } else { 82 list_add(&jeb->list, &c->dirty_list); 83 } 84 return 0; 85 } 86 87 int jffs2_scan_medium(struct jffs2_sb_info *c) 88 { 89 int i, ret; 90 uint32_t empty_blocks = 0, bad_blocks = 0; 91 unsigned char *flashbuf = NULL; 92 uint32_t buf_size = 0; 93 struct jffs2_summary *s = NULL; /* summary info collected by the scan process */ 94 #ifndef __ECOS 95 size_t pointlen; 96 97 if (c->mtd->point) { 98 ret = c->mtd->point (c->mtd, 0, c->mtd->size, &pointlen, &flashbuf); 99 if (!ret && pointlen < c->mtd->size) { 100 /* Don't muck about if it won't let us point to the whole flash */ 101 D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", pointlen)); 102 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size); 103 flashbuf = NULL; 104 } 105 if (ret) 106 D1(printk(KERN_DEBUG "MTD point failed %d\n", ret)); 107 } 108 #endif 109 if (!flashbuf) { 110 /* For NAND it's quicker to read a whole eraseblock at a time, 111 apparently */ 112 if (jffs2_cleanmarker_oob(c)) 113 buf_size = c->sector_size; 114 else 115 buf_size = PAGE_SIZE; 116 117 /* Respect kmalloc limitations */ 118 if (buf_size > 128*1024) 119 buf_size = 128*1024; 120 121 D1(printk(KERN_DEBUG "Allocating readbuf of %d bytes\n", buf_size)); 122 flashbuf = kmalloc(buf_size, GFP_KERNEL); 123 if (!flashbuf) 124 return -ENOMEM; 125 } 126 127 if (jffs2_sum_active()) { 128 s = kmalloc(sizeof(struct jffs2_summary), GFP_KERNEL); 129 if (!s) { 130 JFFS2_WARNING("Can't allocate memory for summary\n"); 131 return -ENOMEM; 132 } 133 memset(s, 0, sizeof(struct jffs2_summary)); 134 } 135 136 for (i=0; i<c->nr_blocks; i++) { 137 struct jffs2_eraseblock *jeb = &c->blocks[i]; 138 139 /* reset summary info for next eraseblock scan */ 140 jffs2_sum_reset_collected(s); 141 142 ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset), 143 buf_size, s); 144 145 if (ret < 0) 146 goto out; 147 148 jffs2_dbg_acct_paranoia_check_nolock(c, jeb); 149 150 /* Now decide which list to put it on */ 151 switch(ret) { 152 case BLK_STATE_ALLFF: 153 /* 154 * Empty block. Since we can't be sure it 155 * was entirely erased, we just queue it for erase 156 * again. It will be marked as such when the erase 157 * is complete. Meanwhile we still count it as empty 158 * for later checks. 159 */ 160 empty_blocks++; 161 list_add(&jeb->list, &c->erase_pending_list); 162 c->nr_erasing_blocks++; 163 break; 164 165 case BLK_STATE_CLEANMARKER: 166 /* Only a CLEANMARKER node is valid */ 167 if (!jeb->dirty_size) { 168 /* It's actually free */ 169 list_add(&jeb->list, &c->free_list); 170 c->nr_free_blocks++; 171 } else { 172 /* Dirt */ 173 D1(printk(KERN_DEBUG "Adding all-dirty block at 0x%08x to erase_pending_list\n", jeb->offset)); 174 list_add(&jeb->list, &c->erase_pending_list); 175 c->nr_erasing_blocks++; 176 } 177 break; 178 179 case BLK_STATE_CLEAN: 180 /* Full (or almost full) of clean data. Clean list */ 181 list_add(&jeb->list, &c->clean_list); 182 break; 183 184 case BLK_STATE_PARTDIRTY: 185 /* Some data, but not full. Dirty list. */ 186 /* We want to remember the block with most free space 187 and stick it in the 'nextblock' position to start writing to it. */ 188 if (jeb->free_size > min_free(c) && 189 (!c->nextblock || c->nextblock->free_size < jeb->free_size)) { 190 /* Better candidate for the next writes to go to */ 191 if (c->nextblock) { 192 ret = file_dirty(c, c->nextblock); 193 if (ret) 194 return ret; 195 /* deleting summary information of the old nextblock */ 196 jffs2_sum_reset_collected(c->summary); 197 } 198 /* update collected summary information for the current nextblock */ 199 jffs2_sum_move_collected(c, s); 200 D1(printk(KERN_DEBUG "jffs2_scan_medium(): new nextblock = 0x%08x\n", jeb->offset)); 201 c->nextblock = jeb; 202 } else { 203 ret = file_dirty(c, jeb); 204 if (ret) 205 return ret; 206 } 207 break; 208 209 case BLK_STATE_ALLDIRTY: 210 /* Nothing valid - not even a clean marker. Needs erasing. */ 211 /* For now we just put it on the erasing list. We'll start the erases later */ 212 D1(printk(KERN_NOTICE "JFFS2: Erase block at 0x%08x is not formatted. It will be erased\n", jeb->offset)); 213 list_add(&jeb->list, &c->erase_pending_list); 214 c->nr_erasing_blocks++; 215 break; 216 217 case BLK_STATE_BADBLOCK: 218 D1(printk(KERN_NOTICE "JFFS2: Block at 0x%08x is bad\n", jeb->offset)); 219 list_add(&jeb->list, &c->bad_list); 220 c->bad_size += c->sector_size; 221 c->free_size -= c->sector_size; 222 bad_blocks++; 223 break; 224 default: 225 printk(KERN_WARNING "jffs2_scan_medium(): unknown block state\n"); 226 BUG(); 227 } 228 } 229 230 /* Nextblock dirty is always seen as wasted, because we cannot recycle it now */ 231 if (c->nextblock && (c->nextblock->dirty_size)) { 232 c->nextblock->wasted_size += c->nextblock->dirty_size; 233 c->wasted_size += c->nextblock->dirty_size; 234 c->dirty_size -= c->nextblock->dirty_size; 235 c->nextblock->dirty_size = 0; 236 } 237 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 238 if (!jffs2_can_mark_obsolete(c) && c->wbuf_pagesize && c->nextblock && (c->nextblock->free_size % c->wbuf_pagesize)) { 239 /* If we're going to start writing into a block which already 240 contains data, and the end of the data isn't page-aligned, 241 skip a little and align it. */ 242 243 uint32_t skip = c->nextblock->free_size % c->wbuf_pagesize; 244 245 D1(printk(KERN_DEBUG "jffs2_scan_medium(): Skipping %d bytes in nextblock to ensure page alignment\n", 246 skip)); 247 jffs2_prealloc_raw_node_refs(c, c->nextblock, 1); 248 jffs2_scan_dirty_space(c, c->nextblock, skip); 249 } 250 #endif 251 if (c->nr_erasing_blocks) { 252 if ( !c->used_size && ((c->nr_free_blocks+empty_blocks+bad_blocks)!= c->nr_blocks || bad_blocks == c->nr_blocks) ) { 253 printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n"); 254 printk(KERN_NOTICE "empty_blocks %d, bad_blocks %d, c->nr_blocks %d\n",empty_blocks,bad_blocks,c->nr_blocks); 255 ret = -EIO; 256 goto out; 257 } 258 jffs2_erase_pending_trigger(c); 259 } 260 ret = 0; 261 out: 262 if (buf_size) 263 kfree(flashbuf); 264 #ifndef __ECOS 265 else 266 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size); 267 #endif 268 if (s) 269 kfree(s); 270 271 return ret; 272 } 273 274 int jffs2_fill_scan_buf (struct jffs2_sb_info *c, void *buf, 275 uint32_t ofs, uint32_t len) 276 { 277 int ret; 278 size_t retlen; 279 280 ret = jffs2_flash_read(c, ofs, len, &retlen, buf); 281 if (ret) { 282 D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", len, ofs, ret)); 283 return ret; 284 } 285 if (retlen < len) { 286 D1(printk(KERN_WARNING "Read at 0x%x gave only 0x%zx bytes\n", ofs, retlen)); 287 return -EIO; 288 } 289 return 0; 290 } 291 292 int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb) 293 { 294 if ((jeb->used_size + jeb->unchecked_size) == PAD(c->cleanmarker_size) && !jeb->dirty_size 295 && (!jeb->first_node || !ref_next(jeb->first_node)) ) 296 return BLK_STATE_CLEANMARKER; 297 298 /* move blocks with max 4 byte dirty space to cleanlist */ 299 else if (!ISDIRTY(c->sector_size - (jeb->used_size + jeb->unchecked_size))) { 300 c->dirty_size -= jeb->dirty_size; 301 c->wasted_size += jeb->dirty_size; 302 jeb->wasted_size += jeb->dirty_size; 303 jeb->dirty_size = 0; 304 return BLK_STATE_CLEAN; 305 } else if (jeb->used_size || jeb->unchecked_size) 306 return BLK_STATE_PARTDIRTY; 307 else 308 return BLK_STATE_ALLDIRTY; 309 } 310 311 #ifdef CONFIG_JFFS2_FS_XATTR 312 static int jffs2_scan_xattr_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 313 struct jffs2_raw_xattr *rx, uint32_t ofs, 314 struct jffs2_summary *s) 315 { 316 struct jffs2_xattr_datum *xd; 317 uint32_t totlen, crc; 318 int err; 319 320 crc = crc32(0, rx, sizeof(struct jffs2_raw_xattr) - 4); 321 if (crc != je32_to_cpu(rx->node_crc)) { 322 if (je32_to_cpu(rx->node_crc) != 0xffffffff) 323 JFFS2_WARNING("node CRC failed at %#08x, read=%#08x, calc=%#08x\n", 324 ofs, je32_to_cpu(rx->node_crc), crc); 325 if ((err = jffs2_scan_dirty_space(c, jeb, je32_to_cpu(rx->totlen)))) 326 return err; 327 return 0; 328 } 329 330 totlen = PAD(sizeof(*rx) + rx->name_len + 1 + je16_to_cpu(rx->value_len)); 331 if (totlen != je32_to_cpu(rx->totlen)) { 332 JFFS2_WARNING("node length mismatch at %#08x, read=%u, calc=%u\n", 333 ofs, je32_to_cpu(rx->totlen), totlen); 334 if ((err = jffs2_scan_dirty_space(c, jeb, je32_to_cpu(rx->totlen)))) 335 return err; 336 return 0; 337 } 338 339 xd = jffs2_setup_xattr_datum(c, je32_to_cpu(rx->xid), je32_to_cpu(rx->version)); 340 if (IS_ERR(xd)) { 341 if (PTR_ERR(xd) == -EEXIST) { 342 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(rx->totlen))))) 343 return err; 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); 352 353 xd->node = jffs2_link_node_ref(c, jeb, ofs | REF_PRISTINE, totlen, NULL); 354 /* FIXME */ xd->node->next_in_ino = (void *)xd; 355 356 if (jffs2_sum_active()) 357 jffs2_sum_add_xattr_mem(s, rx, ofs - jeb->offset); 358 dbg_xattr("scaning xdatum at %#08x (xid=%u, version=%u)\n", 359 ofs, xd->xid, xd->version); 360 return 0; 361 } 362 363 static int jffs2_scan_xref_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 364 struct jffs2_raw_xref *rr, uint32_t ofs, 365 struct jffs2_summary *s) 366 { 367 struct jffs2_xattr_ref *ref; 368 uint32_t crc; 369 int err; 370 371 crc = crc32(0, rr, sizeof(*rr) - 4); 372 if (crc != je32_to_cpu(rr->node_crc)) { 373 if (je32_to_cpu(rr->node_crc) != 0xffffffff) 374 JFFS2_WARNING("node CRC failed at %#08x, read=%#08x, calc=%#08x\n", 375 ofs, je32_to_cpu(rr->node_crc), crc); 376 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(rr->totlen))))) 377 return err; 378 return 0; 379 } 380 381 if (PAD(sizeof(struct jffs2_raw_xref)) != je32_to_cpu(rr->totlen)) { 382 JFFS2_WARNING("node length mismatch at %#08x, read=%u, calc=%u\n", 383 ofs, je32_to_cpu(rr->totlen), 384 PAD(sizeof(struct jffs2_raw_xref))); 385 if ((err = jffs2_scan_dirty_space(c, jeb, je32_to_cpu(rr->totlen)))) 386 return err; 387 return 0; 388 } 389 390 ref = jffs2_alloc_xattr_ref(); 391 if (!ref) 392 return -ENOMEM; 393 394 /* BEFORE jffs2_build_xattr_subsystem() called, 395 * ref->xid is used to store 32bit xid, xd is not used 396 * ref->ino is used to store 32bit inode-number, ic is not used 397 * Thoes variables are declared as union, thus using those 398 * are exclusive. In a similar way, ref->next is temporarily 399 * used to chain all xattr_ref object. It's re-chained to 400 * jffs2_inode_cache in jffs2_build_xattr_subsystem() correctly. 401 */ 402 ref->ino = je32_to_cpu(rr->ino); 403 ref->xid = je32_to_cpu(rr->xid); 404 ref->next = c->xref_temp; 405 c->xref_temp = ref; 406 407 ref->node = jffs2_link_node_ref(c, jeb, ofs | REF_PRISTINE, PAD(je32_to_cpu(rr->totlen)), NULL); 408 /* FIXME */ ref->node->next_in_ino = (void *)ref; 409 410 if (jffs2_sum_active()) 411 jffs2_sum_add_xref_mem(s, rr, ofs - jeb->offset); 412 dbg_xattr("scan xref at %#08x (xid=%u, ino=%u)\n", 413 ofs, ref->xid, ref->ino); 414 return 0; 415 } 416 #endif 417 418 /* Called with 'buf_size == 0' if buf is in fact a pointer _directly_ into 419 the flash, XIP-style */ 420 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 421 unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s) { 422 struct jffs2_unknown_node *node; 423 struct jffs2_unknown_node crcnode; 424 uint32_t ofs, prevofs; 425 uint32_t hdr_crc, buf_ofs, buf_len; 426 int err; 427 int noise = 0; 428 429 430 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 431 int cleanmarkerfound = 0; 432 #endif 433 434 ofs = jeb->offset; 435 prevofs = jeb->offset - 1; 436 437 D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs)); 438 439 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 440 if (jffs2_cleanmarker_oob(c)) { 441 int ret = jffs2_check_nand_cleanmarker(c, jeb); 442 D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n",ret)); 443 /* Even if it's not found, we still scan to see 444 if the block is empty. We use this information 445 to decide whether to erase it or not. */ 446 switch (ret) { 447 case 0: cleanmarkerfound = 1; break; 448 case 1: break; 449 case 2: return BLK_STATE_BADBLOCK; 450 case 3: return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */ 451 default: return ret; 452 } 453 } 454 #endif 455 456 if (jffs2_sum_active()) { 457 struct jffs2_sum_marker *sm; 458 void *sumptr = NULL; 459 uint32_t sumlen; 460 461 if (!buf_size) { 462 /* XIP case. Just look, point at the summary if it's there */ 463 sm = (void *)buf + jeb->offset - sizeof(*sm); 464 if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC) { 465 sumptr = buf + je32_to_cpu(sm->offset); 466 sumlen = c->sector_size - je32_to_cpu(sm->offset); 467 } 468 } else { 469 /* If NAND flash, read a whole page of it. Else just the end */ 470 if (c->wbuf_pagesize) 471 buf_len = c->wbuf_pagesize; 472 else 473 buf_len = sizeof(*sm); 474 475 /* Read as much as we want into the _end_ of the preallocated buffer */ 476 err = jffs2_fill_scan_buf(c, buf + buf_size - buf_len, 477 jeb->offset + c->sector_size - buf_len, 478 buf_len); 479 if (err) 480 return err; 481 482 sm = (void *)buf + buf_size - sizeof(*sm); 483 if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC) { 484 sumlen = c->sector_size - je32_to_cpu(sm->offset); 485 sumptr = buf + buf_size - sumlen; 486 487 /* Now, make sure the summary itself is available */ 488 if (sumlen > buf_size) { 489 /* Need to kmalloc for this. */ 490 sumptr = kmalloc(sumlen, GFP_KERNEL); 491 if (!sumptr) 492 return -ENOMEM; 493 memcpy(sumptr + sumlen - buf_len, buf + buf_size - buf_len, buf_len); 494 } 495 if (buf_len < sumlen) { 496 /* Need to read more so that the entire summary node is present */ 497 err = jffs2_fill_scan_buf(c, sumptr, 498 jeb->offset + c->sector_size - sumlen, 499 sumlen - buf_len); 500 if (err) 501 return err; 502 } 503 } 504 505 } 506 507 if (sumptr) { 508 err = jffs2_sum_scan_sumnode(c, jeb, sumptr, sumlen, &pseudo_random); 509 510 if (buf_size && sumlen > buf_size) 511 kfree(sumptr); 512 /* If it returns with a real error, bail. 513 If it returns positive, that's a block classification 514 (i.e. BLK_STATE_xxx) so return that too. 515 If it returns zero, fall through to full scan. */ 516 if (err) 517 return err; 518 } 519 } 520 521 buf_ofs = jeb->offset; 522 523 if (!buf_size) { 524 /* This is the XIP case -- we're reading _directly_ from the flash chip */ 525 buf_len = c->sector_size; 526 } else { 527 buf_len = EMPTY_SCAN_SIZE(c->sector_size); 528 err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len); 529 if (err) 530 return err; 531 } 532 533 /* We temporarily use 'ofs' as a pointer into the buffer/jeb */ 534 ofs = 0; 535 536 /* Scan only 4KiB of 0xFF before declaring it's empty */ 537 while(ofs < EMPTY_SCAN_SIZE(c->sector_size) && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF) 538 ofs += 4; 539 540 if (ofs == EMPTY_SCAN_SIZE(c->sector_size)) { 541 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 542 if (jffs2_cleanmarker_oob(c)) { 543 /* scan oob, take care of cleanmarker */ 544 int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound); 545 D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret)); 546 switch (ret) { 547 case 0: return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF; 548 case 1: return BLK_STATE_ALLDIRTY; 549 default: return ret; 550 } 551 } 552 #endif 553 D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset)); 554 if (c->cleanmarker_size == 0) 555 return BLK_STATE_CLEANMARKER; /* don't bother with re-erase */ 556 else 557 return BLK_STATE_ALLFF; /* OK to erase if all blocks are like this */ 558 } 559 if (ofs) { 560 D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset, 561 jeb->offset + ofs)); 562 if ((err = jffs2_scan_dirty_space(c, jeb, ofs))) 563 return err; 564 } 565 566 /* Now ofs is a complete physical flash offset as it always was... */ 567 ofs += jeb->offset; 568 569 noise = 10; 570 571 dbg_summary("no summary found in jeb 0x%08x. Apply original scan.\n",jeb->offset); 572 573 scan_more: 574 while(ofs < jeb->offset + c->sector_size) { 575 576 jffs2_dbg_acct_paranoia_check_nolock(c, jeb); 577 578 /* Make sure there are node refs available for use */ 579 err = jffs2_prealloc_raw_node_refs(c, jeb, 2); 580 if (err) 581 return err; 582 583 cond_resched(); 584 585 if (ofs & 3) { 586 printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs); 587 ofs = PAD(ofs); 588 continue; 589 } 590 if (ofs == prevofs) { 591 printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs); 592 if ((err = jffs2_scan_dirty_space(c, jeb, 4))) 593 return err; 594 ofs += 4; 595 continue; 596 } 597 prevofs = ofs; 598 599 if (jeb->offset + c->sector_size < ofs + sizeof(*node)) { 600 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), 601 jeb->offset, c->sector_size, ofs, sizeof(*node))); 602 if ((err = jffs2_scan_dirty_space(c, jeb, (jeb->offset + c->sector_size)-ofs))) 603 return err; 604 break; 605 } 606 607 if (buf_ofs + buf_len < ofs + sizeof(*node)) { 608 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 609 D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n", 610 sizeof(struct jffs2_unknown_node), buf_len, ofs)); 611 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 612 if (err) 613 return err; 614 buf_ofs = ofs; 615 } 616 617 node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs]; 618 619 if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) { 620 uint32_t inbuf_ofs; 621 uint32_t empty_start; 622 623 empty_start = ofs; 624 ofs += 4; 625 626 D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs)); 627 more_empty: 628 inbuf_ofs = ofs - buf_ofs; 629 while (inbuf_ofs < buf_len) { 630 if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff) { 631 printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n", 632 empty_start, ofs); 633 if ((err = jffs2_scan_dirty_space(c, jeb, ofs-empty_start))) 634 return err; 635 goto scan_more; 636 } 637 638 inbuf_ofs+=4; 639 ofs += 4; 640 } 641 /* Ran off end. */ 642 D1(printk(KERN_DEBUG "Empty flash to end of buffer at 0x%08x\n", ofs)); 643 644 /* If we're only checking the beginning of a block with a cleanmarker, 645 bail now */ 646 if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) && 647 c->cleanmarker_size && !jeb->dirty_size && !ref_next(jeb->first_node)) { 648 D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE(c->sector_size))); 649 return BLK_STATE_CLEANMARKER; 650 } 651 652 /* See how much more there is to read in this eraseblock... */ 653 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 654 if (!buf_len) { 655 /* No more to read. Break out of main loop without marking 656 this range of empty space as dirty (because it's not) */ 657 D1(printk(KERN_DEBUG "Empty flash at %08x runs to end of block. Treating as free_space\n", 658 empty_start)); 659 break; 660 } 661 D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs)); 662 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 663 if (err) 664 return err; 665 buf_ofs = ofs; 666 goto more_empty; 667 } 668 669 if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) { 670 printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs); 671 if ((err = jffs2_scan_dirty_space(c, jeb, 4))) 672 return err; 673 ofs += 4; 674 continue; 675 } 676 if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) { 677 D1(printk(KERN_DEBUG "Dirty bitmask at 0x%08x\n", ofs)); 678 if ((err = jffs2_scan_dirty_space(c, jeb, 4))) 679 return err; 680 ofs += 4; 681 continue; 682 } 683 if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) { 684 printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs); 685 printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n"); 686 if ((err = jffs2_scan_dirty_space(c, jeb, 4))) 687 return err; 688 ofs += 4; 689 continue; 690 } 691 if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) { 692 /* OK. We're out of possibilities. Whinge and move on */ 693 noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n", 694 JFFS2_MAGIC_BITMASK, ofs, 695 je16_to_cpu(node->magic)); 696 if ((err = jffs2_scan_dirty_space(c, jeb, 4))) 697 return err; 698 ofs += 4; 699 continue; 700 } 701 /* We seem to have a node of sorts. Check the CRC */ 702 crcnode.magic = node->magic; 703 crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE); 704 crcnode.totlen = node->totlen; 705 hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4); 706 707 if (hdr_crc != je32_to_cpu(node->hdr_crc)) { 708 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", 709 ofs, je16_to_cpu(node->magic), 710 je16_to_cpu(node->nodetype), 711 je32_to_cpu(node->totlen), 712 je32_to_cpu(node->hdr_crc), 713 hdr_crc); 714 if ((err = jffs2_scan_dirty_space(c, jeb, 4))) 715 return err; 716 ofs += 4; 717 continue; 718 } 719 720 if (ofs + je32_to_cpu(node->totlen) > 721 jeb->offset + c->sector_size) { 722 /* Eep. Node goes over the end of the erase block. */ 723 printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n", 724 ofs, je32_to_cpu(node->totlen)); 725 printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n"); 726 if ((err = jffs2_scan_dirty_space(c, jeb, 4))) 727 return err; 728 ofs += 4; 729 continue; 730 } 731 732 if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) { 733 /* Wheee. This is an obsoleted node */ 734 D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs)); 735 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen))))) 736 return err; 737 ofs += PAD(je32_to_cpu(node->totlen)); 738 continue; 739 } 740 741 switch(je16_to_cpu(node->nodetype)) { 742 case JFFS2_NODETYPE_INODE: 743 if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) { 744 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 745 D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n", 746 sizeof(struct jffs2_raw_inode), buf_len, ofs)); 747 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 748 if (err) 749 return err; 750 buf_ofs = ofs; 751 node = (void *)buf; 752 } 753 err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs, s); 754 if (err) return err; 755 ofs += PAD(je32_to_cpu(node->totlen)); 756 break; 757 758 case JFFS2_NODETYPE_DIRENT: 759 if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) { 760 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 761 D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n", 762 je32_to_cpu(node->totlen), buf_len, ofs)); 763 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 764 if (err) 765 return err; 766 buf_ofs = ofs; 767 node = (void *)buf; 768 } 769 err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs, s); 770 if (err) return err; 771 ofs += PAD(je32_to_cpu(node->totlen)); 772 break; 773 774 #ifdef CONFIG_JFFS2_FS_XATTR 775 case JFFS2_NODETYPE_XATTR: 776 if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) { 777 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 778 D1(printk(KERN_DEBUG "Fewer than %d bytes (xattr node)" 779 " left to end of buf. Reading 0x%x at 0x%08x\n", 780 je32_to_cpu(node->totlen), buf_len, ofs)); 781 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 782 if (err) 783 return err; 784 buf_ofs = ofs; 785 node = (void *)buf; 786 } 787 err = jffs2_scan_xattr_node(c, jeb, (void *)node, ofs, s); 788 if (err) 789 return err; 790 ofs += PAD(je32_to_cpu(node->totlen)); 791 break; 792 case JFFS2_NODETYPE_XREF: 793 if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) { 794 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 795 D1(printk(KERN_DEBUG "Fewer than %d bytes (xref node)" 796 " left to end of buf. Reading 0x%x at 0x%08x\n", 797 je32_to_cpu(node->totlen), buf_len, ofs)); 798 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 799 if (err) 800 return err; 801 buf_ofs = ofs; 802 node = (void *)buf; 803 } 804 err = jffs2_scan_xref_node(c, jeb, (void *)node, ofs, s); 805 if (err) 806 return err; 807 ofs += PAD(je32_to_cpu(node->totlen)); 808 break; 809 #endif /* CONFIG_JFFS2_FS_XATTR */ 810 811 case JFFS2_NODETYPE_CLEANMARKER: 812 D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs)); 813 if (je32_to_cpu(node->totlen) != c->cleanmarker_size) { 814 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n", 815 ofs, je32_to_cpu(node->totlen), c->cleanmarker_size); 816 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(sizeof(struct jffs2_unknown_node))))) 817 return err; 818 ofs += PAD(sizeof(struct jffs2_unknown_node)); 819 } else if (jeb->first_node) { 820 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset); 821 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(sizeof(struct jffs2_unknown_node))))) 822 return err; 823 ofs += PAD(sizeof(struct jffs2_unknown_node)); 824 } else { 825 jffs2_link_node_ref(c, jeb, ofs | REF_NORMAL, c->cleanmarker_size, NULL); 826 827 ofs += PAD(c->cleanmarker_size); 828 } 829 break; 830 831 case JFFS2_NODETYPE_PADDING: 832 if (jffs2_sum_active()) 833 jffs2_sum_add_padding_mem(s, je32_to_cpu(node->totlen)); 834 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen))))) 835 return err; 836 ofs += PAD(je32_to_cpu(node->totlen)); 837 break; 838 839 default: 840 switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) { 841 case JFFS2_FEATURE_ROCOMPAT: 842 printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs); 843 c->flags |= JFFS2_SB_FLAG_RO; 844 if (!(jffs2_is_readonly(c))) 845 return -EROFS; 846 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen))))) 847 return err; 848 ofs += PAD(je32_to_cpu(node->totlen)); 849 break; 850 851 case JFFS2_FEATURE_INCOMPAT: 852 printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs); 853 return -EINVAL; 854 855 case JFFS2_FEATURE_RWCOMPAT_DELETE: 856 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs)); 857 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen))))) 858 return err; 859 ofs += PAD(je32_to_cpu(node->totlen)); 860 break; 861 862 case JFFS2_FEATURE_RWCOMPAT_COPY: { 863 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs)); 864 865 jffs2_link_node_ref(c, jeb, ofs | REF_PRISTINE, PAD(je32_to_cpu(node->totlen)), NULL); 866 867 /* We can't summarise nodes we don't grok */ 868 jffs2_sum_disable_collecting(s); 869 ofs += PAD(je32_to_cpu(node->totlen)); 870 break; 871 } 872 } 873 } 874 } 875 876 if (jffs2_sum_active()) { 877 if (PAD(s->sum_size + JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size) { 878 dbg_summary("There is not enough space for " 879 "summary information, disabling for this jeb!\n"); 880 jffs2_sum_disable_collecting(s); 881 } 882 } 883 884 D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x\n", jeb->offset, 885 jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size)); 886 887 /* mark_node_obsolete can add to wasted !! */ 888 if (jeb->wasted_size) { 889 jeb->dirty_size += jeb->wasted_size; 890 c->dirty_size += jeb->wasted_size; 891 c->wasted_size -= jeb->wasted_size; 892 jeb->wasted_size = 0; 893 } 894 895 return jffs2_scan_classify_jeb(c, jeb); 896 } 897 898 struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino) 899 { 900 struct jffs2_inode_cache *ic; 901 902 ic = jffs2_get_ino_cache(c, ino); 903 if (ic) 904 return ic; 905 906 if (ino > c->highest_ino) 907 c->highest_ino = ino; 908 909 ic = jffs2_alloc_inode_cache(); 910 if (!ic) { 911 printk(KERN_NOTICE "jffs2_scan_make_inode_cache(): allocation of inode cache failed\n"); 912 return NULL; 913 } 914 memset(ic, 0, sizeof(*ic)); 915 916 ic->ino = ino; 917 ic->nodes = (void *)ic; 918 jffs2_add_ino_cache(c, ic); 919 if (ino == 1) 920 ic->nlink = 1; 921 return ic; 922 } 923 924 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 925 struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s) 926 { 927 struct jffs2_inode_cache *ic; 928 uint32_t ino = je32_to_cpu(ri->ino); 929 int err; 930 931 D1(printk(KERN_DEBUG "jffs2_scan_inode_node(): Node at 0x%08x\n", ofs)); 932 933 /* We do very little here now. Just check the ino# to which we should attribute 934 this node; we can do all the CRC checking etc. later. There's a tradeoff here -- 935 we used to scan the flash once only, reading everything we want from it into 936 memory, then building all our in-core data structures and freeing the extra 937 information. Now we allow the first part of the mount to complete a lot quicker, 938 but we have to go _back_ to the flash in order to finish the CRC checking, etc. 939 Which means that the _full_ amount of time to get to proper write mode with GC 940 operational may actually be _longer_ than before. Sucks to be me. */ 941 942 ic = jffs2_get_ino_cache(c, ino); 943 if (!ic) { 944 /* Inocache get failed. Either we read a bogus ino# or it's just genuinely the 945 first node we found for this inode. Do a CRC check to protect against the former 946 case */ 947 uint32_t crc = crc32(0, ri, sizeof(*ri)-8); 948 949 if (crc != je32_to_cpu(ri->node_crc)) { 950 printk(KERN_NOTICE "jffs2_scan_inode_node(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 951 ofs, je32_to_cpu(ri->node_crc), crc); 952 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */ 953 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(ri->totlen))))) 954 return err; 955 return 0; 956 } 957 ic = jffs2_scan_make_ino_cache(c, ino); 958 if (!ic) 959 return -ENOMEM; 960 } 961 962 /* Wheee. It worked */ 963 jffs2_link_node_ref(c, jeb, ofs | REF_UNCHECKED, PAD(je32_to_cpu(ri->totlen)), ic); 964 965 D1(printk(KERN_DEBUG "Node is ino #%u, version %d. Range 0x%x-0x%x\n", 966 je32_to_cpu(ri->ino), je32_to_cpu(ri->version), 967 je32_to_cpu(ri->offset), 968 je32_to_cpu(ri->offset)+je32_to_cpu(ri->dsize))); 969 970 pseudo_random += je32_to_cpu(ri->version); 971 972 if (jffs2_sum_active()) { 973 jffs2_sum_add_inode_mem(s, ri, ofs - jeb->offset); 974 } 975 976 return 0; 977 } 978 979 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 980 struct jffs2_raw_dirent *rd, uint32_t ofs, struct jffs2_summary *s) 981 { 982 struct jffs2_full_dirent *fd; 983 struct jffs2_inode_cache *ic; 984 uint32_t crc; 985 int err; 986 987 D1(printk(KERN_DEBUG "jffs2_scan_dirent_node(): Node at 0x%08x\n", ofs)); 988 989 /* We don't get here unless the node is still valid, so we don't have to 990 mask in the ACCURATE bit any more. */ 991 crc = crc32(0, rd, sizeof(*rd)-8); 992 993 if (crc != je32_to_cpu(rd->node_crc)) { 994 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Node CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 995 ofs, je32_to_cpu(rd->node_crc), crc); 996 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */ 997 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(rd->totlen))))) 998 return err; 999 return 0; 1000 } 1001 1002 pseudo_random += je32_to_cpu(rd->version); 1003 1004 fd = jffs2_alloc_full_dirent(rd->nsize+1); 1005 if (!fd) { 1006 return -ENOMEM; 1007 } 1008 memcpy(&fd->name, rd->name, rd->nsize); 1009 fd->name[rd->nsize] = 0; 1010 1011 crc = crc32(0, fd->name, rd->nsize); 1012 if (crc != je32_to_cpu(rd->name_crc)) { 1013 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 1014 ofs, je32_to_cpu(rd->name_crc), crc); 1015 D1(printk(KERN_NOTICE "Name for which CRC failed is (now) '%s', ino #%d\n", fd->name, je32_to_cpu(rd->ino))); 1016 jffs2_free_full_dirent(fd); 1017 /* FIXME: Why do we believe totlen? */ 1018 /* We believe totlen because the CRC on the node _header_ was OK, just the name failed. */ 1019 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(rd->totlen))))) 1020 return err; 1021 return 0; 1022 } 1023 ic = jffs2_scan_make_ino_cache(c, je32_to_cpu(rd->pino)); 1024 if (!ic) { 1025 jffs2_free_full_dirent(fd); 1026 return -ENOMEM; 1027 } 1028 1029 fd->raw = jffs2_link_node_ref(c, jeb, ofs | REF_PRISTINE, PAD(je32_to_cpu(rd->totlen)), ic); 1030 1031 fd->next = NULL; 1032 fd->version = je32_to_cpu(rd->version); 1033 fd->ino = je32_to_cpu(rd->ino); 1034 fd->nhash = full_name_hash(fd->name, rd->nsize); 1035 fd->type = rd->type; 1036 jffs2_add_fd_to_list(c, fd, &ic->scan_dents); 1037 1038 if (jffs2_sum_active()) { 1039 jffs2_sum_add_dirent_mem(s, rd, ofs - jeb->offset); 1040 } 1041 1042 return 0; 1043 } 1044 1045 static int count_list(struct list_head *l) 1046 { 1047 uint32_t count = 0; 1048 struct list_head *tmp; 1049 1050 list_for_each(tmp, l) { 1051 count++; 1052 } 1053 return count; 1054 } 1055 1056 /* Note: This breaks if list_empty(head). I don't care. You 1057 might, if you copy this code and use it elsewhere :) */ 1058 static void rotate_list(struct list_head *head, uint32_t count) 1059 { 1060 struct list_head *n = head->next; 1061 1062 list_del(head); 1063 while(count--) { 1064 n = n->next; 1065 } 1066 list_add(head, n); 1067 } 1068 1069 void jffs2_rotate_lists(struct jffs2_sb_info *c) 1070 { 1071 uint32_t x; 1072 uint32_t rotateby; 1073 1074 x = count_list(&c->clean_list); 1075 if (x) { 1076 rotateby = pseudo_random % x; 1077 rotate_list((&c->clean_list), rotateby); 1078 } 1079 1080 x = count_list(&c->very_dirty_list); 1081 if (x) { 1082 rotateby = pseudo_random % x; 1083 rotate_list((&c->very_dirty_list), rotateby); 1084 } 1085 1086 x = count_list(&c->dirty_list); 1087 if (x) { 1088 rotateby = pseudo_random % x; 1089 rotate_list((&c->dirty_list), rotateby); 1090 } 1091 1092 x = count_list(&c->erasable_list); 1093 if (x) { 1094 rotateby = pseudo_random % x; 1095 rotate_list((&c->erasable_list), rotateby); 1096 } 1097 1098 if (c->nr_erasing_blocks) { 1099 rotateby = pseudo_random % c->nr_erasing_blocks; 1100 rotate_list((&c->erase_pending_list), rotateby); 1101 } 1102 1103 if (c->nr_free_blocks) { 1104 rotateby = pseudo_random % c->nr_free_blocks; 1105 rotate_list((&c->free_list), rotateby); 1106 } 1107 } 1108