1 /* 2 * This file is part of UBIFS. 3 * 4 * Copyright (C) 2006-2008 Nokia Corporation. 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 * 8 * Authors: Artem Bityutskiy (Битюцкий Артём) 9 * Adrian Hunter 10 */ 11 12 /* 13 * This file implements UBIFS superblock. The superblock is stored at the first 14 * LEB of the volume and is never changed by UBIFS. Only user-space tools may 15 * change it. The superblock node mostly contains geometry information. 16 */ 17 18 #include "ubifs.h" 19 #define __UBOOT__ 20 #ifndef __UBOOT__ 21 #include <linux/slab.h> 22 #include <linux/random.h> 23 #include <linux/math64.h> 24 #else 25 26 #include <linux/compat.h> 27 #include <linux/err.h> 28 #include <ubi_uboot.h> 29 #include <linux/stat.h> 30 #endif 31 32 /* 33 * Default journal size in logical eraseblocks as a percent of total 34 * flash size. 35 */ 36 #define DEFAULT_JNL_PERCENT 5 37 38 /* Default maximum journal size in bytes */ 39 #define DEFAULT_MAX_JNL (32*1024*1024) 40 41 /* Default indexing tree fanout */ 42 #define DEFAULT_FANOUT 8 43 44 /* Default number of data journal heads */ 45 #define DEFAULT_JHEADS_CNT 1 46 47 /* Default positions of different LEBs in the main area */ 48 #define DEFAULT_IDX_LEB 0 49 #define DEFAULT_DATA_LEB 1 50 #define DEFAULT_GC_LEB 2 51 52 /* Default number of LEB numbers in LPT's save table */ 53 #define DEFAULT_LSAVE_CNT 256 54 55 /* Default reserved pool size as a percent of maximum free space */ 56 #define DEFAULT_RP_PERCENT 5 57 58 /* The default maximum size of reserved pool in bytes */ 59 #define DEFAULT_MAX_RP_SIZE (5*1024*1024) 60 61 /* Default time granularity in nanoseconds */ 62 #define DEFAULT_TIME_GRAN 1000000000 63 64 #ifndef __UBOOT__ 65 /** 66 * create_default_filesystem - format empty UBI volume. 67 * @c: UBIFS file-system description object 68 * 69 * This function creates default empty file-system. Returns zero in case of 70 * success and a negative error code in case of failure. 71 */ 72 static int create_default_filesystem(struct ubifs_info *c) 73 { 74 struct ubifs_sb_node *sup; 75 struct ubifs_mst_node *mst; 76 struct ubifs_idx_node *idx; 77 struct ubifs_branch *br; 78 struct ubifs_ino_node *ino; 79 struct ubifs_cs_node *cs; 80 union ubifs_key key; 81 int err, tmp, jnl_lebs, log_lebs, max_buds, main_lebs, main_first; 82 int lpt_lebs, lpt_first, orph_lebs, big_lpt, ino_waste, sup_flags = 0; 83 int min_leb_cnt = UBIFS_MIN_LEB_CNT; 84 long long tmp64, main_bytes; 85 __le64 tmp_le64; 86 87 /* Some functions called from here depend on the @c->key_len filed */ 88 c->key_len = UBIFS_SK_LEN; 89 90 /* 91 * First of all, we have to calculate default file-system geometry - 92 * log size, journal size, etc. 93 */ 94 if (c->leb_cnt < 0x7FFFFFFF / DEFAULT_JNL_PERCENT) 95 /* We can first multiply then divide and have no overflow */ 96 jnl_lebs = c->leb_cnt * DEFAULT_JNL_PERCENT / 100; 97 else 98 jnl_lebs = (c->leb_cnt / 100) * DEFAULT_JNL_PERCENT; 99 100 if (jnl_lebs < UBIFS_MIN_JNL_LEBS) 101 jnl_lebs = UBIFS_MIN_JNL_LEBS; 102 if (jnl_lebs * c->leb_size > DEFAULT_MAX_JNL) 103 jnl_lebs = DEFAULT_MAX_JNL / c->leb_size; 104 105 /* 106 * The log should be large enough to fit reference nodes for all bud 107 * LEBs. Because buds do not have to start from the beginning of LEBs 108 * (half of the LEB may contain committed data), the log should 109 * generally be larger, make it twice as large. 110 */ 111 tmp = 2 * (c->ref_node_alsz * jnl_lebs) + c->leb_size - 1; 112 log_lebs = tmp / c->leb_size; 113 /* Plus one LEB reserved for commit */ 114 log_lebs += 1; 115 if (c->leb_cnt - min_leb_cnt > 8) { 116 /* And some extra space to allow writes while committing */ 117 log_lebs += 1; 118 min_leb_cnt += 1; 119 } 120 121 max_buds = jnl_lebs - log_lebs; 122 if (max_buds < UBIFS_MIN_BUD_LEBS) 123 max_buds = UBIFS_MIN_BUD_LEBS; 124 125 /* 126 * Orphan nodes are stored in a separate area. One node can store a lot 127 * of orphan inode numbers, but when new orphan comes we just add a new 128 * orphan node. At some point the nodes are consolidated into one 129 * orphan node. 130 */ 131 orph_lebs = UBIFS_MIN_ORPH_LEBS; 132 if (c->leb_cnt - min_leb_cnt > 1) 133 /* 134 * For debugging purposes it is better to have at least 2 135 * orphan LEBs, because the orphan subsystem would need to do 136 * consolidations and would be stressed more. 137 */ 138 orph_lebs += 1; 139 140 main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - log_lebs; 141 main_lebs -= orph_lebs; 142 143 lpt_first = UBIFS_LOG_LNUM + log_lebs; 144 c->lsave_cnt = DEFAULT_LSAVE_CNT; 145 c->max_leb_cnt = c->leb_cnt; 146 err = ubifs_create_dflt_lpt(c, &main_lebs, lpt_first, &lpt_lebs, 147 &big_lpt); 148 if (err) 149 return err; 150 151 dbg_gen("LEB Properties Tree created (LEBs %d-%d)", lpt_first, 152 lpt_first + lpt_lebs - 1); 153 154 main_first = c->leb_cnt - main_lebs; 155 156 /* Create default superblock */ 157 tmp = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size); 158 sup = kzalloc(tmp, GFP_KERNEL); 159 if (!sup) 160 return -ENOMEM; 161 162 tmp64 = (long long)max_buds * c->leb_size; 163 if (big_lpt) 164 sup_flags |= UBIFS_FLG_BIGLPT; 165 166 sup->ch.node_type = UBIFS_SB_NODE; 167 sup->key_hash = UBIFS_KEY_HASH_R5; 168 sup->flags = cpu_to_le32(sup_flags); 169 sup->min_io_size = cpu_to_le32(c->min_io_size); 170 sup->leb_size = cpu_to_le32(c->leb_size); 171 sup->leb_cnt = cpu_to_le32(c->leb_cnt); 172 sup->max_leb_cnt = cpu_to_le32(c->max_leb_cnt); 173 sup->max_bud_bytes = cpu_to_le64(tmp64); 174 sup->log_lebs = cpu_to_le32(log_lebs); 175 sup->lpt_lebs = cpu_to_le32(lpt_lebs); 176 sup->orph_lebs = cpu_to_le32(orph_lebs); 177 sup->jhead_cnt = cpu_to_le32(DEFAULT_JHEADS_CNT); 178 sup->fanout = cpu_to_le32(DEFAULT_FANOUT); 179 sup->lsave_cnt = cpu_to_le32(c->lsave_cnt); 180 sup->fmt_version = cpu_to_le32(UBIFS_FORMAT_VERSION); 181 sup->time_gran = cpu_to_le32(DEFAULT_TIME_GRAN); 182 if (c->mount_opts.override_compr) 183 sup->default_compr = cpu_to_le16(c->mount_opts.compr_type); 184 else 185 sup->default_compr = cpu_to_le16(UBIFS_COMPR_LZO); 186 187 generate_random_uuid(sup->uuid); 188 189 main_bytes = (long long)main_lebs * c->leb_size; 190 tmp64 = div_u64(main_bytes * DEFAULT_RP_PERCENT, 100); 191 if (tmp64 > DEFAULT_MAX_RP_SIZE) 192 tmp64 = DEFAULT_MAX_RP_SIZE; 193 sup->rp_size = cpu_to_le64(tmp64); 194 sup->ro_compat_version = cpu_to_le32(UBIFS_RO_COMPAT_VERSION); 195 196 err = ubifs_write_node(c, sup, UBIFS_SB_NODE_SZ, 0, 0); 197 kfree(sup); 198 if (err) 199 return err; 200 201 dbg_gen("default superblock created at LEB 0:0"); 202 203 /* Create default master node */ 204 mst = kzalloc(c->mst_node_alsz, GFP_KERNEL); 205 if (!mst) 206 return -ENOMEM; 207 208 mst->ch.node_type = UBIFS_MST_NODE; 209 mst->log_lnum = cpu_to_le32(UBIFS_LOG_LNUM); 210 mst->highest_inum = cpu_to_le64(UBIFS_FIRST_INO); 211 mst->cmt_no = 0; 212 mst->root_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB); 213 mst->root_offs = 0; 214 tmp = ubifs_idx_node_sz(c, 1); 215 mst->root_len = cpu_to_le32(tmp); 216 mst->gc_lnum = cpu_to_le32(main_first + DEFAULT_GC_LEB); 217 mst->ihead_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB); 218 mst->ihead_offs = cpu_to_le32(ALIGN(tmp, c->min_io_size)); 219 mst->index_size = cpu_to_le64(ALIGN(tmp, 8)); 220 mst->lpt_lnum = cpu_to_le32(c->lpt_lnum); 221 mst->lpt_offs = cpu_to_le32(c->lpt_offs); 222 mst->nhead_lnum = cpu_to_le32(c->nhead_lnum); 223 mst->nhead_offs = cpu_to_le32(c->nhead_offs); 224 mst->ltab_lnum = cpu_to_le32(c->ltab_lnum); 225 mst->ltab_offs = cpu_to_le32(c->ltab_offs); 226 mst->lsave_lnum = cpu_to_le32(c->lsave_lnum); 227 mst->lsave_offs = cpu_to_le32(c->lsave_offs); 228 mst->lscan_lnum = cpu_to_le32(main_first); 229 mst->empty_lebs = cpu_to_le32(main_lebs - 2); 230 mst->idx_lebs = cpu_to_le32(1); 231 mst->leb_cnt = cpu_to_le32(c->leb_cnt); 232 233 /* Calculate lprops statistics */ 234 tmp64 = main_bytes; 235 tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size); 236 tmp64 -= ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size); 237 mst->total_free = cpu_to_le64(tmp64); 238 239 tmp64 = ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size); 240 ino_waste = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size) - 241 UBIFS_INO_NODE_SZ; 242 tmp64 += ino_waste; 243 tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), 8); 244 mst->total_dirty = cpu_to_le64(tmp64); 245 246 /* The indexing LEB does not contribute to dark space */ 247 tmp64 = ((long long)(c->main_lebs - 1) * c->dark_wm); 248 mst->total_dark = cpu_to_le64(tmp64); 249 250 mst->total_used = cpu_to_le64(UBIFS_INO_NODE_SZ); 251 252 err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM, 0); 253 if (err) { 254 kfree(mst); 255 return err; 256 } 257 err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM + 1, 258 0); 259 kfree(mst); 260 if (err) 261 return err; 262 263 dbg_gen("default master node created at LEB %d:0", UBIFS_MST_LNUM); 264 265 /* Create the root indexing node */ 266 tmp = ubifs_idx_node_sz(c, 1); 267 idx = kzalloc(ALIGN(tmp, c->min_io_size), GFP_KERNEL); 268 if (!idx) 269 return -ENOMEM; 270 271 c->key_fmt = UBIFS_SIMPLE_KEY_FMT; 272 c->key_hash = key_r5_hash; 273 274 idx->ch.node_type = UBIFS_IDX_NODE; 275 idx->child_cnt = cpu_to_le16(1); 276 ino_key_init(c, &key, UBIFS_ROOT_INO); 277 br = ubifs_idx_branch(c, idx, 0); 278 key_write_idx(c, &key, &br->key); 279 br->lnum = cpu_to_le32(main_first + DEFAULT_DATA_LEB); 280 br->len = cpu_to_le32(UBIFS_INO_NODE_SZ); 281 err = ubifs_write_node(c, idx, tmp, main_first + DEFAULT_IDX_LEB, 0); 282 kfree(idx); 283 if (err) 284 return err; 285 286 dbg_gen("default root indexing node created LEB %d:0", 287 main_first + DEFAULT_IDX_LEB); 288 289 /* Create default root inode */ 290 tmp = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size); 291 ino = kzalloc(tmp, GFP_KERNEL); 292 if (!ino) 293 return -ENOMEM; 294 295 ino_key_init_flash(c, &ino->key, UBIFS_ROOT_INO); 296 ino->ch.node_type = UBIFS_INO_NODE; 297 ino->creat_sqnum = cpu_to_le64(++c->max_sqnum); 298 ino->nlink = cpu_to_le32(2); 299 tmp_le64 = cpu_to_le64(CURRENT_TIME_SEC.tv_sec); 300 ino->atime_sec = tmp_le64; 301 ino->ctime_sec = tmp_le64; 302 ino->mtime_sec = tmp_le64; 303 ino->atime_nsec = 0; 304 ino->ctime_nsec = 0; 305 ino->mtime_nsec = 0; 306 ino->mode = cpu_to_le32(S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO); 307 ino->size = cpu_to_le64(UBIFS_INO_NODE_SZ); 308 309 /* Set compression enabled by default */ 310 ino->flags = cpu_to_le32(UBIFS_COMPR_FL); 311 312 err = ubifs_write_node(c, ino, UBIFS_INO_NODE_SZ, 313 main_first + DEFAULT_DATA_LEB, 0); 314 kfree(ino); 315 if (err) 316 return err; 317 318 dbg_gen("root inode created at LEB %d:0", 319 main_first + DEFAULT_DATA_LEB); 320 321 /* 322 * The first node in the log has to be the commit start node. This is 323 * always the case during normal file-system operation. Write a fake 324 * commit start node to the log. 325 */ 326 tmp = ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size); 327 cs = kzalloc(tmp, GFP_KERNEL); 328 if (!cs) 329 return -ENOMEM; 330 331 cs->ch.node_type = UBIFS_CS_NODE; 332 err = ubifs_write_node(c, cs, UBIFS_CS_NODE_SZ, UBIFS_LOG_LNUM, 0); 333 kfree(cs); 334 335 ubifs_msg("default file-system created"); 336 return 0; 337 } 338 #endif 339 340 /** 341 * validate_sb - validate superblock node. 342 * @c: UBIFS file-system description object 343 * @sup: superblock node 344 * 345 * This function validates superblock node @sup. Since most of data was read 346 * from the superblock and stored in @c, the function validates fields in @c 347 * instead. Returns zero in case of success and %-EINVAL in case of validation 348 * failure. 349 */ 350 static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup) 351 { 352 long long max_bytes; 353 int err = 1, min_leb_cnt; 354 355 if (!c->key_hash) { 356 err = 2; 357 goto failed; 358 } 359 360 if (sup->key_fmt != UBIFS_SIMPLE_KEY_FMT) { 361 err = 3; 362 goto failed; 363 } 364 365 if (le32_to_cpu(sup->min_io_size) != c->min_io_size) { 366 ubifs_err("min. I/O unit mismatch: %d in superblock, %d real", 367 le32_to_cpu(sup->min_io_size), c->min_io_size); 368 goto failed; 369 } 370 371 if (le32_to_cpu(sup->leb_size) != c->leb_size) { 372 ubifs_err("LEB size mismatch: %d in superblock, %d real", 373 le32_to_cpu(sup->leb_size), c->leb_size); 374 goto failed; 375 } 376 377 if (c->log_lebs < UBIFS_MIN_LOG_LEBS || 378 c->lpt_lebs < UBIFS_MIN_LPT_LEBS || 379 c->orph_lebs < UBIFS_MIN_ORPH_LEBS || 380 c->main_lebs < UBIFS_MIN_MAIN_LEBS) { 381 err = 4; 382 goto failed; 383 } 384 385 /* 386 * Calculate minimum allowed amount of main area LEBs. This is very 387 * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we 388 * have just read from the superblock. 389 */ 390 min_leb_cnt = UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs; 391 min_leb_cnt += c->lpt_lebs + c->orph_lebs + c->jhead_cnt + 6; 392 393 if (c->leb_cnt < min_leb_cnt || c->leb_cnt > c->vi.size) { 394 ubifs_err("bad LEB count: %d in superblock, %d on UBI volume, %d minimum required", 395 c->leb_cnt, c->vi.size, min_leb_cnt); 396 goto failed; 397 } 398 399 if (c->max_leb_cnt < c->leb_cnt) { 400 ubifs_err("max. LEB count %d less than LEB count %d", 401 c->max_leb_cnt, c->leb_cnt); 402 goto failed; 403 } 404 405 if (c->main_lebs < UBIFS_MIN_MAIN_LEBS) { 406 ubifs_err("too few main LEBs count %d, must be at least %d", 407 c->main_lebs, UBIFS_MIN_MAIN_LEBS); 408 goto failed; 409 } 410 411 max_bytes = (long long)c->leb_size * UBIFS_MIN_BUD_LEBS; 412 if (c->max_bud_bytes < max_bytes) { 413 ubifs_err("too small journal (%lld bytes), must be at least %lld bytes", 414 c->max_bud_bytes, max_bytes); 415 goto failed; 416 } 417 418 max_bytes = (long long)c->leb_size * c->main_lebs; 419 if (c->max_bud_bytes > max_bytes) { 420 ubifs_err("too large journal size (%lld bytes), only %lld bytes available in the main area", 421 c->max_bud_bytes, max_bytes); 422 goto failed; 423 } 424 425 if (c->jhead_cnt < NONDATA_JHEADS_CNT + 1 || 426 c->jhead_cnt > NONDATA_JHEADS_CNT + UBIFS_MAX_JHEADS) { 427 err = 9; 428 goto failed; 429 } 430 431 if (c->fanout < UBIFS_MIN_FANOUT || 432 ubifs_idx_node_sz(c, c->fanout) > c->leb_size) { 433 err = 10; 434 goto failed; 435 } 436 437 if (c->lsave_cnt < 0 || (c->lsave_cnt > DEFAULT_LSAVE_CNT && 438 c->lsave_cnt > c->max_leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - 439 c->log_lebs - c->lpt_lebs - c->orph_lebs)) { 440 err = 11; 441 goto failed; 442 } 443 444 if (UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs + c->lpt_lebs + 445 c->orph_lebs + c->main_lebs != c->leb_cnt) { 446 err = 12; 447 goto failed; 448 } 449 450 if (c->default_compr < 0 || c->default_compr >= UBIFS_COMPR_TYPES_CNT) { 451 err = 13; 452 goto failed; 453 } 454 455 if (c->rp_size < 0 || max_bytes < c->rp_size) { 456 err = 14; 457 goto failed; 458 } 459 460 if (le32_to_cpu(sup->time_gran) > 1000000000 || 461 le32_to_cpu(sup->time_gran) < 1) { 462 err = 15; 463 goto failed; 464 } 465 466 return 0; 467 468 failed: 469 ubifs_err("bad superblock, error %d", err); 470 ubifs_dump_node(c, sup); 471 return -EINVAL; 472 } 473 474 /** 475 * ubifs_read_sb_node - read superblock node. 476 * @c: UBIFS file-system description object 477 * 478 * This function returns a pointer to the superblock node or a negative error 479 * code. Note, the user of this function is responsible of kfree()'ing the 480 * returned superblock buffer. 481 */ 482 struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c) 483 { 484 struct ubifs_sb_node *sup; 485 int err; 486 487 sup = kmalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_NOFS); 488 if (!sup) 489 return ERR_PTR(-ENOMEM); 490 491 err = ubifs_read_node(c, sup, UBIFS_SB_NODE, UBIFS_SB_NODE_SZ, 492 UBIFS_SB_LNUM, 0); 493 if (err) { 494 kfree(sup); 495 return ERR_PTR(err); 496 } 497 498 return sup; 499 } 500 501 /** 502 * ubifs_write_sb_node - write superblock node. 503 * @c: UBIFS file-system description object 504 * @sup: superblock node read with 'ubifs_read_sb_node()' 505 * 506 * This function returns %0 on success and a negative error code on failure. 507 */ 508 int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup) 509 { 510 int len = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size); 511 512 ubifs_prepare_node(c, sup, UBIFS_SB_NODE_SZ, 1); 513 return ubifs_leb_change(c, UBIFS_SB_LNUM, sup, len); 514 } 515 516 /** 517 * ubifs_read_superblock - read superblock. 518 * @c: UBIFS file-system description object 519 * 520 * This function finds, reads and checks the superblock. If an empty UBI volume 521 * is being mounted, this function creates default superblock. Returns zero in 522 * case of success, and a negative error code in case of failure. 523 */ 524 int ubifs_read_superblock(struct ubifs_info *c) 525 { 526 int err, sup_flags; 527 struct ubifs_sb_node *sup; 528 529 if (c->empty) { 530 #ifndef __UBOOT__ 531 err = create_default_filesystem(c); 532 if (err) 533 return err; 534 #else 535 printf("No UBIFS filesystem found!\n"); 536 return -1; 537 #endif 538 } 539 540 sup = ubifs_read_sb_node(c); 541 if (IS_ERR(sup)) 542 return PTR_ERR(sup); 543 544 c->fmt_version = le32_to_cpu(sup->fmt_version); 545 c->ro_compat_version = le32_to_cpu(sup->ro_compat_version); 546 547 /* 548 * The software supports all previous versions but not future versions, 549 * due to the unavailability of time-travelling equipment. 550 */ 551 if (c->fmt_version > UBIFS_FORMAT_VERSION) { 552 ubifs_assert(!c->ro_media || c->ro_mount); 553 if (!c->ro_mount || 554 c->ro_compat_version > UBIFS_RO_COMPAT_VERSION) { 555 ubifs_err("on-flash format version is w%d/r%d, but software only supports up to version w%d/r%d", 556 c->fmt_version, c->ro_compat_version, 557 UBIFS_FORMAT_VERSION, 558 UBIFS_RO_COMPAT_VERSION); 559 if (c->ro_compat_version <= UBIFS_RO_COMPAT_VERSION) { 560 ubifs_msg("only R/O mounting is possible"); 561 err = -EROFS; 562 } else 563 err = -EINVAL; 564 goto out; 565 } 566 567 /* 568 * The FS is mounted R/O, and the media format is 569 * R/O-compatible with the UBIFS implementation, so we can 570 * mount. 571 */ 572 c->rw_incompat = 1; 573 } 574 575 if (c->fmt_version < 3) { 576 ubifs_err("on-flash format version %d is not supported", 577 c->fmt_version); 578 err = -EINVAL; 579 goto out; 580 } 581 582 switch (sup->key_hash) { 583 case UBIFS_KEY_HASH_R5: 584 c->key_hash = key_r5_hash; 585 c->key_hash_type = UBIFS_KEY_HASH_R5; 586 break; 587 588 case UBIFS_KEY_HASH_TEST: 589 c->key_hash = key_test_hash; 590 c->key_hash_type = UBIFS_KEY_HASH_TEST; 591 break; 592 }; 593 594 c->key_fmt = sup->key_fmt; 595 596 switch (c->key_fmt) { 597 case UBIFS_SIMPLE_KEY_FMT: 598 c->key_len = UBIFS_SK_LEN; 599 break; 600 default: 601 ubifs_err("unsupported key format"); 602 err = -EINVAL; 603 goto out; 604 } 605 606 c->leb_cnt = le32_to_cpu(sup->leb_cnt); 607 c->max_leb_cnt = le32_to_cpu(sup->max_leb_cnt); 608 c->max_bud_bytes = le64_to_cpu(sup->max_bud_bytes); 609 c->log_lebs = le32_to_cpu(sup->log_lebs); 610 c->lpt_lebs = le32_to_cpu(sup->lpt_lebs); 611 c->orph_lebs = le32_to_cpu(sup->orph_lebs); 612 c->jhead_cnt = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT; 613 c->fanout = le32_to_cpu(sup->fanout); 614 c->lsave_cnt = le32_to_cpu(sup->lsave_cnt); 615 c->rp_size = le64_to_cpu(sup->rp_size); 616 #ifndef __UBOOT__ 617 c->rp_uid = make_kuid(&init_user_ns, le32_to_cpu(sup->rp_uid)); 618 c->rp_gid = make_kgid(&init_user_ns, le32_to_cpu(sup->rp_gid)); 619 #else 620 c->rp_uid.val = le32_to_cpu(sup->rp_uid); 621 c->rp_gid.val = le32_to_cpu(sup->rp_gid); 622 #endif 623 sup_flags = le32_to_cpu(sup->flags); 624 if (!c->mount_opts.override_compr) 625 c->default_compr = le16_to_cpu(sup->default_compr); 626 627 c->vfs_sb->s_time_gran = le32_to_cpu(sup->time_gran); 628 memcpy(&c->uuid, &sup->uuid, 16); 629 c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT); 630 c->space_fixup = !!(sup_flags & UBIFS_FLG_SPACE_FIXUP); 631 632 /* Automatically increase file system size to the maximum size */ 633 c->old_leb_cnt = c->leb_cnt; 634 if (c->leb_cnt < c->vi.size && c->leb_cnt < c->max_leb_cnt) { 635 c->leb_cnt = min_t(int, c->max_leb_cnt, c->vi.size); 636 if (c->ro_mount) 637 dbg_mnt("Auto resizing (ro) from %d LEBs to %d LEBs", 638 c->old_leb_cnt, c->leb_cnt); 639 #ifndef __UBOOT__ 640 else { 641 dbg_mnt("Auto resizing (sb) from %d LEBs to %d LEBs", 642 c->old_leb_cnt, c->leb_cnt); 643 sup->leb_cnt = cpu_to_le32(c->leb_cnt); 644 err = ubifs_write_sb_node(c, sup); 645 if (err) 646 goto out; 647 c->old_leb_cnt = c->leb_cnt; 648 } 649 #endif 650 } 651 652 c->log_bytes = (long long)c->log_lebs * c->leb_size; 653 c->log_last = UBIFS_LOG_LNUM + c->log_lebs - 1; 654 c->lpt_first = UBIFS_LOG_LNUM + c->log_lebs; 655 c->lpt_last = c->lpt_first + c->lpt_lebs - 1; 656 c->orph_first = c->lpt_last + 1; 657 c->orph_last = c->orph_first + c->orph_lebs - 1; 658 c->main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS; 659 c->main_lebs -= c->log_lebs + c->lpt_lebs + c->orph_lebs; 660 c->main_first = c->leb_cnt - c->main_lebs; 661 662 err = validate_sb(c, sup); 663 out: 664 kfree(sup); 665 return err; 666 } 667 668 /** 669 * fixup_leb - fixup/unmap an LEB containing free space. 670 * @c: UBIFS file-system description object 671 * @lnum: the LEB number to fix up 672 * @len: number of used bytes in LEB (starting at offset 0) 673 * 674 * This function reads the contents of the given LEB number @lnum, then fixes 675 * it up, so that empty min. I/O units in the end of LEB are actually erased on 676 * flash (rather than being just all-0xff real data). If the LEB is completely 677 * empty, it is simply unmapped. 678 */ 679 static int fixup_leb(struct ubifs_info *c, int lnum, int len) 680 { 681 int err; 682 683 ubifs_assert(len >= 0); 684 ubifs_assert(len % c->min_io_size == 0); 685 ubifs_assert(len < c->leb_size); 686 687 if (len == 0) { 688 dbg_mnt("unmap empty LEB %d", lnum); 689 return ubifs_leb_unmap(c, lnum); 690 } 691 692 dbg_mnt("fixup LEB %d, data len %d", lnum, len); 693 err = ubifs_leb_read(c, lnum, c->sbuf, 0, len, 1); 694 if (err) 695 return err; 696 697 return ubifs_leb_change(c, lnum, c->sbuf, len); 698 } 699 700 /** 701 * fixup_free_space - find & remap all LEBs containing free space. 702 * @c: UBIFS file-system description object 703 * 704 * This function walks through all LEBs in the filesystem and fiexes up those 705 * containing free/empty space. 706 */ 707 static int fixup_free_space(struct ubifs_info *c) 708 { 709 int lnum, err = 0; 710 struct ubifs_lprops *lprops; 711 712 ubifs_get_lprops(c); 713 714 /* Fixup LEBs in the master area */ 715 for (lnum = UBIFS_MST_LNUM; lnum < UBIFS_LOG_LNUM; lnum++) { 716 err = fixup_leb(c, lnum, c->mst_offs + c->mst_node_alsz); 717 if (err) 718 goto out; 719 } 720 721 /* Unmap unused log LEBs */ 722 lnum = ubifs_next_log_lnum(c, c->lhead_lnum); 723 while (lnum != c->ltail_lnum) { 724 err = fixup_leb(c, lnum, 0); 725 if (err) 726 goto out; 727 lnum = ubifs_next_log_lnum(c, lnum); 728 } 729 730 /* 731 * Fixup the log head which contains the only a CS node at the 732 * beginning. 733 */ 734 err = fixup_leb(c, c->lhead_lnum, 735 ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size)); 736 if (err) 737 goto out; 738 739 /* Fixup LEBs in the LPT area */ 740 for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) { 741 int free = c->ltab[lnum - c->lpt_first].free; 742 743 if (free > 0) { 744 err = fixup_leb(c, lnum, c->leb_size - free); 745 if (err) 746 goto out; 747 } 748 } 749 750 /* Unmap LEBs in the orphans area */ 751 for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { 752 err = fixup_leb(c, lnum, 0); 753 if (err) 754 goto out; 755 } 756 757 /* Fixup LEBs in the main area */ 758 for (lnum = c->main_first; lnum < c->leb_cnt; lnum++) { 759 lprops = ubifs_lpt_lookup(c, lnum); 760 if (IS_ERR(lprops)) { 761 err = PTR_ERR(lprops); 762 goto out; 763 } 764 765 if (lprops->free > 0) { 766 err = fixup_leb(c, lnum, c->leb_size - lprops->free); 767 if (err) 768 goto out; 769 } 770 } 771 772 out: 773 ubifs_release_lprops(c); 774 return err; 775 } 776 777 /** 778 * ubifs_fixup_free_space - find & fix all LEBs with free space. 779 * @c: UBIFS file-system description object 780 * 781 * This function fixes up LEBs containing free space on first mount, if the 782 * appropriate flag was set when the FS was created. Each LEB with one or more 783 * empty min. I/O unit (i.e. free-space-count > 0) is re-written, to make sure 784 * the free space is actually erased. E.g., this is necessary for some NAND 785 * chips, since the free space may have been programmed like real "0xff" data 786 * (generating a non-0xff ECC), causing future writes to the not-really-erased 787 * NAND pages to behave badly. After the space is fixed up, the superblock flag 788 * is cleared, so that this is skipped for all future mounts. 789 */ 790 int ubifs_fixup_free_space(struct ubifs_info *c) 791 { 792 int err; 793 struct ubifs_sb_node *sup; 794 795 ubifs_assert(c->space_fixup); 796 ubifs_assert(!c->ro_mount); 797 798 ubifs_msg("start fixing up free space"); 799 800 err = fixup_free_space(c); 801 if (err) 802 return err; 803 804 sup = ubifs_read_sb_node(c); 805 if (IS_ERR(sup)) 806 return PTR_ERR(sup); 807 808 /* Free-space fixup is no longer required */ 809 c->space_fixup = 0; 810 sup->flags &= cpu_to_le32(~UBIFS_FLG_SPACE_FIXUP); 811 812 err = ubifs_write_sb_node(c, sup); 813 kfree(sup); 814 if (err) 815 return err; 816 817 ubifs_msg("free space fixup complete"); 818 return err; 819 } 820