1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * This file is part of UBIFS. 4 * 5 * Copyright (C) 2006-2008 Nokia Corporation. 6 * 7 * Authors: Artem Bityutskiy (Битюцкий Артём) 8 * Adrian Hunter 9 */ 10 11 /* 12 * This file implements UBIFS initialization and VFS superblock operations. Some 13 * initialization stuff which is rather large and complex is placed at 14 * corresponding subsystems, but most of it is here. 15 */ 16 17 #include <linux/init.h> 18 #include <linux/slab.h> 19 #include <linux/module.h> 20 #include <linux/ctype.h> 21 #include <linux/kthread.h> 22 #include <linux/parser.h> 23 #include <linux/seq_file.h> 24 #include <linux/mount.h> 25 #include <linux/math64.h> 26 #include <linux/writeback.h> 27 #include "ubifs.h" 28 29 /* 30 * Maximum amount of memory we may 'kmalloc()' without worrying that we are 31 * allocating too much. 32 */ 33 #define UBIFS_KMALLOC_OK (128*1024) 34 35 /* Slab cache for UBIFS inodes */ 36 static struct kmem_cache *ubifs_inode_slab; 37 38 /* UBIFS TNC shrinker description */ 39 static struct shrinker ubifs_shrinker_info = { 40 .scan_objects = ubifs_shrink_scan, 41 .count_objects = ubifs_shrink_count, 42 .seeks = DEFAULT_SEEKS, 43 }; 44 45 /** 46 * validate_inode - validate inode. 47 * @c: UBIFS file-system description object 48 * @inode: the inode to validate 49 * 50 * This is a helper function for 'ubifs_iget()' which validates various fields 51 * of a newly built inode to make sure they contain sane values and prevent 52 * possible vulnerabilities. Returns zero if the inode is all right and 53 * a non-zero error code if not. 54 */ 55 static int validate_inode(struct ubifs_info *c, const struct inode *inode) 56 { 57 int err; 58 const struct ubifs_inode *ui = ubifs_inode(inode); 59 60 if (inode->i_size > c->max_inode_sz) { 61 ubifs_err(c, "inode is too large (%lld)", 62 (long long)inode->i_size); 63 return 1; 64 } 65 66 if (ui->compr_type >= UBIFS_COMPR_TYPES_CNT) { 67 ubifs_err(c, "unknown compression type %d", ui->compr_type); 68 return 2; 69 } 70 71 if (ui->xattr_names + ui->xattr_cnt > XATTR_LIST_MAX) 72 return 3; 73 74 if (ui->data_len < 0 || ui->data_len > UBIFS_MAX_INO_DATA) 75 return 4; 76 77 if (ui->xattr && !S_ISREG(inode->i_mode)) 78 return 5; 79 80 if (!ubifs_compr_present(c, ui->compr_type)) { 81 ubifs_warn(c, "inode %lu uses '%s' compression, but it was not compiled in", 82 inode->i_ino, ubifs_compr_name(c, ui->compr_type)); 83 } 84 85 err = dbg_check_dir(c, inode); 86 return err; 87 } 88 89 struct inode *ubifs_iget(struct super_block *sb, unsigned long inum) 90 { 91 int err; 92 union ubifs_key key; 93 struct ubifs_ino_node *ino; 94 struct ubifs_info *c = sb->s_fs_info; 95 struct inode *inode; 96 struct ubifs_inode *ui; 97 98 dbg_gen("inode %lu", inum); 99 100 inode = iget_locked(sb, inum); 101 if (!inode) 102 return ERR_PTR(-ENOMEM); 103 if (!(inode->i_state & I_NEW)) 104 return inode; 105 ui = ubifs_inode(inode); 106 107 ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS); 108 if (!ino) { 109 err = -ENOMEM; 110 goto out; 111 } 112 113 ino_key_init(c, &key, inode->i_ino); 114 115 err = ubifs_tnc_lookup(c, &key, ino); 116 if (err) 117 goto out_ino; 118 119 inode->i_flags |= S_NOCMTIME; 120 121 if (!IS_ENABLED(CONFIG_UBIFS_ATIME_SUPPORT)) 122 inode->i_flags |= S_NOATIME; 123 124 set_nlink(inode, le32_to_cpu(ino->nlink)); 125 i_uid_write(inode, le32_to_cpu(ino->uid)); 126 i_gid_write(inode, le32_to_cpu(ino->gid)); 127 inode->i_atime.tv_sec = (int64_t)le64_to_cpu(ino->atime_sec); 128 inode->i_atime.tv_nsec = le32_to_cpu(ino->atime_nsec); 129 inode->i_mtime.tv_sec = (int64_t)le64_to_cpu(ino->mtime_sec); 130 inode->i_mtime.tv_nsec = le32_to_cpu(ino->mtime_nsec); 131 inode->i_ctime.tv_sec = (int64_t)le64_to_cpu(ino->ctime_sec); 132 inode->i_ctime.tv_nsec = le32_to_cpu(ino->ctime_nsec); 133 inode->i_mode = le32_to_cpu(ino->mode); 134 inode->i_size = le64_to_cpu(ino->size); 135 136 ui->data_len = le32_to_cpu(ino->data_len); 137 ui->flags = le32_to_cpu(ino->flags); 138 ui->compr_type = le16_to_cpu(ino->compr_type); 139 ui->creat_sqnum = le64_to_cpu(ino->creat_sqnum); 140 ui->xattr_cnt = le32_to_cpu(ino->xattr_cnt); 141 ui->xattr_size = le32_to_cpu(ino->xattr_size); 142 ui->xattr_names = le32_to_cpu(ino->xattr_names); 143 ui->synced_i_size = ui->ui_size = inode->i_size; 144 145 ui->xattr = (ui->flags & UBIFS_XATTR_FL) ? 1 : 0; 146 147 err = validate_inode(c, inode); 148 if (err) 149 goto out_invalid; 150 151 switch (inode->i_mode & S_IFMT) { 152 case S_IFREG: 153 inode->i_mapping->a_ops = &ubifs_file_address_operations; 154 inode->i_op = &ubifs_file_inode_operations; 155 inode->i_fop = &ubifs_file_operations; 156 if (ui->xattr) { 157 ui->data = kmalloc(ui->data_len + 1, GFP_NOFS); 158 if (!ui->data) { 159 err = -ENOMEM; 160 goto out_ino; 161 } 162 memcpy(ui->data, ino->data, ui->data_len); 163 ((char *)ui->data)[ui->data_len] = '\0'; 164 } else if (ui->data_len != 0) { 165 err = 10; 166 goto out_invalid; 167 } 168 break; 169 case S_IFDIR: 170 inode->i_op = &ubifs_dir_inode_operations; 171 inode->i_fop = &ubifs_dir_operations; 172 if (ui->data_len != 0) { 173 err = 11; 174 goto out_invalid; 175 } 176 break; 177 case S_IFLNK: 178 inode->i_op = &ubifs_symlink_inode_operations; 179 if (ui->data_len <= 0 || ui->data_len > UBIFS_MAX_INO_DATA) { 180 err = 12; 181 goto out_invalid; 182 } 183 ui->data = kmalloc(ui->data_len + 1, GFP_NOFS); 184 if (!ui->data) { 185 err = -ENOMEM; 186 goto out_ino; 187 } 188 memcpy(ui->data, ino->data, ui->data_len); 189 ((char *)ui->data)[ui->data_len] = '\0'; 190 break; 191 case S_IFBLK: 192 case S_IFCHR: 193 { 194 dev_t rdev; 195 union ubifs_dev_desc *dev; 196 197 ui->data = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS); 198 if (!ui->data) { 199 err = -ENOMEM; 200 goto out_ino; 201 } 202 203 dev = (union ubifs_dev_desc *)ino->data; 204 if (ui->data_len == sizeof(dev->new)) 205 rdev = new_decode_dev(le32_to_cpu(dev->new)); 206 else if (ui->data_len == sizeof(dev->huge)) 207 rdev = huge_decode_dev(le64_to_cpu(dev->huge)); 208 else { 209 err = 13; 210 goto out_invalid; 211 } 212 memcpy(ui->data, ino->data, ui->data_len); 213 inode->i_op = &ubifs_file_inode_operations; 214 init_special_inode(inode, inode->i_mode, rdev); 215 break; 216 } 217 case S_IFSOCK: 218 case S_IFIFO: 219 inode->i_op = &ubifs_file_inode_operations; 220 init_special_inode(inode, inode->i_mode, 0); 221 if (ui->data_len != 0) { 222 err = 14; 223 goto out_invalid; 224 } 225 break; 226 default: 227 err = 15; 228 goto out_invalid; 229 } 230 231 kfree(ino); 232 ubifs_set_inode_flags(inode); 233 unlock_new_inode(inode); 234 return inode; 235 236 out_invalid: 237 ubifs_err(c, "inode %lu validation failed, error %d", inode->i_ino, err); 238 ubifs_dump_node(c, ino); 239 ubifs_dump_inode(c, inode); 240 err = -EINVAL; 241 out_ino: 242 kfree(ino); 243 out: 244 ubifs_err(c, "failed to read inode %lu, error %d", inode->i_ino, err); 245 iget_failed(inode); 246 return ERR_PTR(err); 247 } 248 249 static struct inode *ubifs_alloc_inode(struct super_block *sb) 250 { 251 struct ubifs_inode *ui; 252 253 ui = kmem_cache_alloc(ubifs_inode_slab, GFP_NOFS); 254 if (!ui) 255 return NULL; 256 257 memset((void *)ui + sizeof(struct inode), 0, 258 sizeof(struct ubifs_inode) - sizeof(struct inode)); 259 mutex_init(&ui->ui_mutex); 260 spin_lock_init(&ui->ui_lock); 261 return &ui->vfs_inode; 262 }; 263 264 static void ubifs_free_inode(struct inode *inode) 265 { 266 struct ubifs_inode *ui = ubifs_inode(inode); 267 268 kfree(ui->data); 269 fscrypt_free_inode(inode); 270 271 kmem_cache_free(ubifs_inode_slab, ui); 272 } 273 274 /* 275 * Note, Linux write-back code calls this without 'i_mutex'. 276 */ 277 static int ubifs_write_inode(struct inode *inode, struct writeback_control *wbc) 278 { 279 int err = 0; 280 struct ubifs_info *c = inode->i_sb->s_fs_info; 281 struct ubifs_inode *ui = ubifs_inode(inode); 282 283 ubifs_assert(c, !ui->xattr); 284 if (is_bad_inode(inode)) 285 return 0; 286 287 mutex_lock(&ui->ui_mutex); 288 /* 289 * Due to races between write-back forced by budgeting 290 * (see 'sync_some_inodes()') and background write-back, the inode may 291 * have already been synchronized, do not do this again. This might 292 * also happen if it was synchronized in an VFS operation, e.g. 293 * 'ubifs_link()'. 294 */ 295 if (!ui->dirty) { 296 mutex_unlock(&ui->ui_mutex); 297 return 0; 298 } 299 300 /* 301 * As an optimization, do not write orphan inodes to the media just 302 * because this is not needed. 303 */ 304 dbg_gen("inode %lu, mode %#x, nlink %u", 305 inode->i_ino, (int)inode->i_mode, inode->i_nlink); 306 if (inode->i_nlink) { 307 err = ubifs_jnl_write_inode(c, inode); 308 if (err) 309 ubifs_err(c, "can't write inode %lu, error %d", 310 inode->i_ino, err); 311 else 312 err = dbg_check_inode_size(c, inode, ui->ui_size); 313 } 314 315 ui->dirty = 0; 316 mutex_unlock(&ui->ui_mutex); 317 ubifs_release_dirty_inode_budget(c, ui); 318 return err; 319 } 320 321 static void ubifs_evict_inode(struct inode *inode) 322 { 323 int err; 324 struct ubifs_info *c = inode->i_sb->s_fs_info; 325 struct ubifs_inode *ui = ubifs_inode(inode); 326 327 if (ui->xattr) 328 /* 329 * Extended attribute inode deletions are fully handled in 330 * 'ubifs_removexattr()'. These inodes are special and have 331 * limited usage, so there is nothing to do here. 332 */ 333 goto out; 334 335 dbg_gen("inode %lu, mode %#x", inode->i_ino, (int)inode->i_mode); 336 ubifs_assert(c, !atomic_read(&inode->i_count)); 337 338 truncate_inode_pages_final(&inode->i_data); 339 340 if (inode->i_nlink) 341 goto done; 342 343 if (is_bad_inode(inode)) 344 goto out; 345 346 ui->ui_size = inode->i_size = 0; 347 err = ubifs_jnl_delete_inode(c, inode); 348 if (err) 349 /* 350 * Worst case we have a lost orphan inode wasting space, so a 351 * simple error message is OK here. 352 */ 353 ubifs_err(c, "can't delete inode %lu, error %d", 354 inode->i_ino, err); 355 356 out: 357 if (ui->dirty) 358 ubifs_release_dirty_inode_budget(c, ui); 359 else { 360 /* We've deleted something - clean the "no space" flags */ 361 c->bi.nospace = c->bi.nospace_rp = 0; 362 smp_wmb(); 363 } 364 done: 365 clear_inode(inode); 366 fscrypt_put_encryption_info(inode); 367 } 368 369 static void ubifs_dirty_inode(struct inode *inode, int flags) 370 { 371 struct ubifs_info *c = inode->i_sb->s_fs_info; 372 struct ubifs_inode *ui = ubifs_inode(inode); 373 374 ubifs_assert(c, mutex_is_locked(&ui->ui_mutex)); 375 if (!ui->dirty) { 376 ui->dirty = 1; 377 dbg_gen("inode %lu", inode->i_ino); 378 } 379 } 380 381 static int ubifs_statfs(struct dentry *dentry, struct kstatfs *buf) 382 { 383 struct ubifs_info *c = dentry->d_sb->s_fs_info; 384 unsigned long long free; 385 __le32 *uuid = (__le32 *)c->uuid; 386 387 free = ubifs_get_free_space(c); 388 dbg_gen("free space %lld bytes (%lld blocks)", 389 free, free >> UBIFS_BLOCK_SHIFT); 390 391 buf->f_type = UBIFS_SUPER_MAGIC; 392 buf->f_bsize = UBIFS_BLOCK_SIZE; 393 buf->f_blocks = c->block_cnt; 394 buf->f_bfree = free >> UBIFS_BLOCK_SHIFT; 395 if (free > c->report_rp_size) 396 buf->f_bavail = (free - c->report_rp_size) >> UBIFS_BLOCK_SHIFT; 397 else 398 buf->f_bavail = 0; 399 buf->f_files = 0; 400 buf->f_ffree = 0; 401 buf->f_namelen = UBIFS_MAX_NLEN; 402 buf->f_fsid.val[0] = le32_to_cpu(uuid[0]) ^ le32_to_cpu(uuid[2]); 403 buf->f_fsid.val[1] = le32_to_cpu(uuid[1]) ^ le32_to_cpu(uuid[3]); 404 ubifs_assert(c, buf->f_bfree <= c->block_cnt); 405 return 0; 406 } 407 408 static int ubifs_show_options(struct seq_file *s, struct dentry *root) 409 { 410 struct ubifs_info *c = root->d_sb->s_fs_info; 411 412 if (c->mount_opts.unmount_mode == 2) 413 seq_puts(s, ",fast_unmount"); 414 else if (c->mount_opts.unmount_mode == 1) 415 seq_puts(s, ",norm_unmount"); 416 417 if (c->mount_opts.bulk_read == 2) 418 seq_puts(s, ",bulk_read"); 419 else if (c->mount_opts.bulk_read == 1) 420 seq_puts(s, ",no_bulk_read"); 421 422 if (c->mount_opts.chk_data_crc == 2) 423 seq_puts(s, ",chk_data_crc"); 424 else if (c->mount_opts.chk_data_crc == 1) 425 seq_puts(s, ",no_chk_data_crc"); 426 427 if (c->mount_opts.override_compr) { 428 seq_printf(s, ",compr=%s", 429 ubifs_compr_name(c, c->mount_opts.compr_type)); 430 } 431 432 seq_printf(s, ",assert=%s", ubifs_assert_action_name(c)); 433 seq_printf(s, ",ubi=%d,vol=%d", c->vi.ubi_num, c->vi.vol_id); 434 435 return 0; 436 } 437 438 static int ubifs_sync_fs(struct super_block *sb, int wait) 439 { 440 int i, err; 441 struct ubifs_info *c = sb->s_fs_info; 442 443 /* 444 * Zero @wait is just an advisory thing to help the file system shove 445 * lots of data into the queues, and there will be the second 446 * '->sync_fs()' call, with non-zero @wait. 447 */ 448 if (!wait) 449 return 0; 450 451 /* 452 * Synchronize write buffers, because 'ubifs_run_commit()' does not 453 * do this if it waits for an already running commit. 454 */ 455 for (i = 0; i < c->jhead_cnt; i++) { 456 err = ubifs_wbuf_sync(&c->jheads[i].wbuf); 457 if (err) 458 return err; 459 } 460 461 /* 462 * Strictly speaking, it is not necessary to commit the journal here, 463 * synchronizing write-buffers would be enough. But committing makes 464 * UBIFS free space predictions much more accurate, so we want to let 465 * the user be able to get more accurate results of 'statfs()' after 466 * they synchronize the file system. 467 */ 468 err = ubifs_run_commit(c); 469 if (err) 470 return err; 471 472 return ubi_sync(c->vi.ubi_num); 473 } 474 475 /** 476 * init_constants_early - initialize UBIFS constants. 477 * @c: UBIFS file-system description object 478 * 479 * This function initialize UBIFS constants which do not need the superblock to 480 * be read. It also checks that the UBI volume satisfies basic UBIFS 481 * requirements. Returns zero in case of success and a negative error code in 482 * case of failure. 483 */ 484 static int init_constants_early(struct ubifs_info *c) 485 { 486 if (c->vi.corrupted) { 487 ubifs_warn(c, "UBI volume is corrupted - read-only mode"); 488 c->ro_media = 1; 489 } 490 491 if (c->di.ro_mode) { 492 ubifs_msg(c, "read-only UBI device"); 493 c->ro_media = 1; 494 } 495 496 if (c->vi.vol_type == UBI_STATIC_VOLUME) { 497 ubifs_msg(c, "static UBI volume - read-only mode"); 498 c->ro_media = 1; 499 } 500 501 c->leb_cnt = c->vi.size; 502 c->leb_size = c->vi.usable_leb_size; 503 c->leb_start = c->di.leb_start; 504 c->half_leb_size = c->leb_size / 2; 505 c->min_io_size = c->di.min_io_size; 506 c->min_io_shift = fls(c->min_io_size) - 1; 507 c->max_write_size = c->di.max_write_size; 508 c->max_write_shift = fls(c->max_write_size) - 1; 509 510 if (c->leb_size < UBIFS_MIN_LEB_SZ) { 511 ubifs_errc(c, "too small LEBs (%d bytes), min. is %d bytes", 512 c->leb_size, UBIFS_MIN_LEB_SZ); 513 return -EINVAL; 514 } 515 516 if (c->leb_cnt < UBIFS_MIN_LEB_CNT) { 517 ubifs_errc(c, "too few LEBs (%d), min. is %d", 518 c->leb_cnt, UBIFS_MIN_LEB_CNT); 519 return -EINVAL; 520 } 521 522 if (!is_power_of_2(c->min_io_size)) { 523 ubifs_errc(c, "bad min. I/O size %d", c->min_io_size); 524 return -EINVAL; 525 } 526 527 /* 528 * Maximum write size has to be greater or equivalent to min. I/O 529 * size, and be multiple of min. I/O size. 530 */ 531 if (c->max_write_size < c->min_io_size || 532 c->max_write_size % c->min_io_size || 533 !is_power_of_2(c->max_write_size)) { 534 ubifs_errc(c, "bad write buffer size %d for %d min. I/O unit", 535 c->max_write_size, c->min_io_size); 536 return -EINVAL; 537 } 538 539 /* 540 * UBIFS aligns all node to 8-byte boundary, so to make function in 541 * io.c simpler, assume minimum I/O unit size to be 8 bytes if it is 542 * less than 8. 543 */ 544 if (c->min_io_size < 8) { 545 c->min_io_size = 8; 546 c->min_io_shift = 3; 547 if (c->max_write_size < c->min_io_size) { 548 c->max_write_size = c->min_io_size; 549 c->max_write_shift = c->min_io_shift; 550 } 551 } 552 553 c->ref_node_alsz = ALIGN(UBIFS_REF_NODE_SZ, c->min_io_size); 554 c->mst_node_alsz = ALIGN(UBIFS_MST_NODE_SZ, c->min_io_size); 555 556 /* 557 * Initialize node length ranges which are mostly needed for node 558 * length validation. 559 */ 560 c->ranges[UBIFS_PAD_NODE].len = UBIFS_PAD_NODE_SZ; 561 c->ranges[UBIFS_SB_NODE].len = UBIFS_SB_NODE_SZ; 562 c->ranges[UBIFS_MST_NODE].len = UBIFS_MST_NODE_SZ; 563 c->ranges[UBIFS_REF_NODE].len = UBIFS_REF_NODE_SZ; 564 c->ranges[UBIFS_TRUN_NODE].len = UBIFS_TRUN_NODE_SZ; 565 c->ranges[UBIFS_CS_NODE].len = UBIFS_CS_NODE_SZ; 566 c->ranges[UBIFS_AUTH_NODE].min_len = UBIFS_AUTH_NODE_SZ; 567 c->ranges[UBIFS_AUTH_NODE].max_len = UBIFS_AUTH_NODE_SZ + 568 UBIFS_MAX_HMAC_LEN; 569 c->ranges[UBIFS_SIG_NODE].min_len = UBIFS_SIG_NODE_SZ; 570 c->ranges[UBIFS_SIG_NODE].max_len = c->leb_size - UBIFS_SB_NODE_SZ; 571 572 c->ranges[UBIFS_INO_NODE].min_len = UBIFS_INO_NODE_SZ; 573 c->ranges[UBIFS_INO_NODE].max_len = UBIFS_MAX_INO_NODE_SZ; 574 c->ranges[UBIFS_ORPH_NODE].min_len = 575 UBIFS_ORPH_NODE_SZ + sizeof(__le64); 576 c->ranges[UBIFS_ORPH_NODE].max_len = c->leb_size; 577 c->ranges[UBIFS_DENT_NODE].min_len = UBIFS_DENT_NODE_SZ; 578 c->ranges[UBIFS_DENT_NODE].max_len = UBIFS_MAX_DENT_NODE_SZ; 579 c->ranges[UBIFS_XENT_NODE].min_len = UBIFS_XENT_NODE_SZ; 580 c->ranges[UBIFS_XENT_NODE].max_len = UBIFS_MAX_XENT_NODE_SZ; 581 c->ranges[UBIFS_DATA_NODE].min_len = UBIFS_DATA_NODE_SZ; 582 c->ranges[UBIFS_DATA_NODE].max_len = UBIFS_MAX_DATA_NODE_SZ; 583 /* 584 * Minimum indexing node size is amended later when superblock is 585 * read and the key length is known. 586 */ 587 c->ranges[UBIFS_IDX_NODE].min_len = UBIFS_IDX_NODE_SZ + UBIFS_BRANCH_SZ; 588 /* 589 * Maximum indexing node size is amended later when superblock is 590 * read and the fanout is known. 591 */ 592 c->ranges[UBIFS_IDX_NODE].max_len = INT_MAX; 593 594 /* 595 * Initialize dead and dark LEB space watermarks. See gc.c for comments 596 * about these values. 597 */ 598 c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size); 599 c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size); 600 601 /* 602 * Calculate how many bytes would be wasted at the end of LEB if it was 603 * fully filled with data nodes of maximum size. This is used in 604 * calculations when reporting free space. 605 */ 606 c->leb_overhead = c->leb_size % UBIFS_MAX_DATA_NODE_SZ; 607 608 /* Buffer size for bulk-reads */ 609 c->max_bu_buf_len = UBIFS_MAX_BULK_READ * UBIFS_MAX_DATA_NODE_SZ; 610 if (c->max_bu_buf_len > c->leb_size) 611 c->max_bu_buf_len = c->leb_size; 612 613 /* Log is ready, preserve one LEB for commits. */ 614 c->min_log_bytes = c->leb_size; 615 616 return 0; 617 } 618 619 /** 620 * bud_wbuf_callback - bud LEB write-buffer synchronization call-back. 621 * @c: UBIFS file-system description object 622 * @lnum: LEB the write-buffer was synchronized to 623 * @free: how many free bytes left in this LEB 624 * @pad: how many bytes were padded 625 * 626 * This is a callback function which is called by the I/O unit when the 627 * write-buffer is synchronized. We need this to correctly maintain space 628 * accounting in bud logical eraseblocks. This function returns zero in case of 629 * success and a negative error code in case of failure. 630 * 631 * This function actually belongs to the journal, but we keep it here because 632 * we want to keep it static. 633 */ 634 static int bud_wbuf_callback(struct ubifs_info *c, int lnum, int free, int pad) 635 { 636 return ubifs_update_one_lp(c, lnum, free, pad, 0, 0); 637 } 638 639 /* 640 * init_constants_sb - initialize UBIFS constants. 641 * @c: UBIFS file-system description object 642 * 643 * This is a helper function which initializes various UBIFS constants after 644 * the superblock has been read. It also checks various UBIFS parameters and 645 * makes sure they are all right. Returns zero in case of success and a 646 * negative error code in case of failure. 647 */ 648 static int init_constants_sb(struct ubifs_info *c) 649 { 650 int tmp, err; 651 long long tmp64; 652 653 c->main_bytes = (long long)c->main_lebs * c->leb_size; 654 c->max_znode_sz = sizeof(struct ubifs_znode) + 655 c->fanout * sizeof(struct ubifs_zbranch); 656 657 tmp = ubifs_idx_node_sz(c, 1); 658 c->ranges[UBIFS_IDX_NODE].min_len = tmp; 659 c->min_idx_node_sz = ALIGN(tmp, 8); 660 661 tmp = ubifs_idx_node_sz(c, c->fanout); 662 c->ranges[UBIFS_IDX_NODE].max_len = tmp; 663 c->max_idx_node_sz = ALIGN(tmp, 8); 664 665 /* Make sure LEB size is large enough to fit full commit */ 666 tmp = UBIFS_CS_NODE_SZ + UBIFS_REF_NODE_SZ * c->jhead_cnt; 667 tmp = ALIGN(tmp, c->min_io_size); 668 if (tmp > c->leb_size) { 669 ubifs_err(c, "too small LEB size %d, at least %d needed", 670 c->leb_size, tmp); 671 return -EINVAL; 672 } 673 674 /* 675 * Make sure that the log is large enough to fit reference nodes for 676 * all buds plus one reserved LEB. 677 */ 678 tmp64 = c->max_bud_bytes + c->leb_size - 1; 679 c->max_bud_cnt = div_u64(tmp64, c->leb_size); 680 tmp = (c->ref_node_alsz * c->max_bud_cnt + c->leb_size - 1); 681 tmp /= c->leb_size; 682 tmp += 1; 683 if (c->log_lebs < tmp) { 684 ubifs_err(c, "too small log %d LEBs, required min. %d LEBs", 685 c->log_lebs, tmp); 686 return -EINVAL; 687 } 688 689 /* 690 * When budgeting we assume worst-case scenarios when the pages are not 691 * be compressed and direntries are of the maximum size. 692 * 693 * Note, data, which may be stored in inodes is budgeted separately, so 694 * it is not included into 'c->bi.inode_budget'. 695 */ 696 c->bi.page_budget = UBIFS_MAX_DATA_NODE_SZ * UBIFS_BLOCKS_PER_PAGE; 697 c->bi.inode_budget = UBIFS_INO_NODE_SZ; 698 c->bi.dent_budget = UBIFS_MAX_DENT_NODE_SZ; 699 700 /* 701 * When the amount of flash space used by buds becomes 702 * 'c->max_bud_bytes', UBIFS just blocks all writers and starts commit. 703 * The writers are unblocked when the commit is finished. To avoid 704 * writers to be blocked UBIFS initiates background commit in advance, 705 * when number of bud bytes becomes above the limit defined below. 706 */ 707 c->bg_bud_bytes = (c->max_bud_bytes * 13) >> 4; 708 709 /* 710 * Ensure minimum journal size. All the bytes in the journal heads are 711 * considered to be used, when calculating the current journal usage. 712 * Consequently, if the journal is too small, UBIFS will treat it as 713 * always full. 714 */ 715 tmp64 = (long long)(c->jhead_cnt + 1) * c->leb_size + 1; 716 if (c->bg_bud_bytes < tmp64) 717 c->bg_bud_bytes = tmp64; 718 if (c->max_bud_bytes < tmp64 + c->leb_size) 719 c->max_bud_bytes = tmp64 + c->leb_size; 720 721 err = ubifs_calc_lpt_geom(c); 722 if (err) 723 return err; 724 725 /* Initialize effective LEB size used in budgeting calculations */ 726 c->idx_leb_size = c->leb_size - c->max_idx_node_sz; 727 return 0; 728 } 729 730 /* 731 * init_constants_master - initialize UBIFS constants. 732 * @c: UBIFS file-system description object 733 * 734 * This is a helper function which initializes various UBIFS constants after 735 * the master node has been read. It also checks various UBIFS parameters and 736 * makes sure they are all right. 737 */ 738 static void init_constants_master(struct ubifs_info *c) 739 { 740 long long tmp64; 741 742 c->bi.min_idx_lebs = ubifs_calc_min_idx_lebs(c); 743 c->report_rp_size = ubifs_reported_space(c, c->rp_size); 744 745 /* 746 * Calculate total amount of FS blocks. This number is not used 747 * internally because it does not make much sense for UBIFS, but it is 748 * necessary to report something for the 'statfs()' call. 749 * 750 * Subtract the LEB reserved for GC, the LEB which is reserved for 751 * deletions, minimum LEBs for the index, and assume only one journal 752 * head is available. 753 */ 754 tmp64 = c->main_lebs - 1 - 1 - MIN_INDEX_LEBS - c->jhead_cnt + 1; 755 tmp64 *= (long long)c->leb_size - c->leb_overhead; 756 tmp64 = ubifs_reported_space(c, tmp64); 757 c->block_cnt = tmp64 >> UBIFS_BLOCK_SHIFT; 758 } 759 760 /** 761 * take_gc_lnum - reserve GC LEB. 762 * @c: UBIFS file-system description object 763 * 764 * This function ensures that the LEB reserved for garbage collection is marked 765 * as "taken" in lprops. We also have to set free space to LEB size and dirty 766 * space to zero, because lprops may contain out-of-date information if the 767 * file-system was un-mounted before it has been committed. This function 768 * returns zero in case of success and a negative error code in case of 769 * failure. 770 */ 771 static int take_gc_lnum(struct ubifs_info *c) 772 { 773 int err; 774 775 if (c->gc_lnum == -1) { 776 ubifs_err(c, "no LEB for GC"); 777 return -EINVAL; 778 } 779 780 /* And we have to tell lprops that this LEB is taken */ 781 err = ubifs_change_one_lp(c, c->gc_lnum, c->leb_size, 0, 782 LPROPS_TAKEN, 0, 0); 783 return err; 784 } 785 786 /** 787 * alloc_wbufs - allocate write-buffers. 788 * @c: UBIFS file-system description object 789 * 790 * This helper function allocates and initializes UBIFS write-buffers. Returns 791 * zero in case of success and %-ENOMEM in case of failure. 792 */ 793 static int alloc_wbufs(struct ubifs_info *c) 794 { 795 int i, err; 796 797 c->jheads = kcalloc(c->jhead_cnt, sizeof(struct ubifs_jhead), 798 GFP_KERNEL); 799 if (!c->jheads) 800 return -ENOMEM; 801 802 /* Initialize journal heads */ 803 for (i = 0; i < c->jhead_cnt; i++) { 804 INIT_LIST_HEAD(&c->jheads[i].buds_list); 805 err = ubifs_wbuf_init(c, &c->jheads[i].wbuf); 806 if (err) 807 return err; 808 809 c->jheads[i].wbuf.sync_callback = &bud_wbuf_callback; 810 c->jheads[i].wbuf.jhead = i; 811 c->jheads[i].grouped = 1; 812 c->jheads[i].log_hash = ubifs_hash_get_desc(c); 813 if (IS_ERR(c->jheads[i].log_hash)) 814 goto out; 815 } 816 817 /* 818 * Garbage Collector head does not need to be synchronized by timer. 819 * Also GC head nodes are not grouped. 820 */ 821 c->jheads[GCHD].wbuf.no_timer = 1; 822 c->jheads[GCHD].grouped = 0; 823 824 return 0; 825 826 out: 827 while (i--) 828 kfree(c->jheads[i].log_hash); 829 830 return err; 831 } 832 833 /** 834 * free_wbufs - free write-buffers. 835 * @c: UBIFS file-system description object 836 */ 837 static void free_wbufs(struct ubifs_info *c) 838 { 839 int i; 840 841 if (c->jheads) { 842 for (i = 0; i < c->jhead_cnt; i++) { 843 kfree(c->jheads[i].wbuf.buf); 844 kfree(c->jheads[i].wbuf.inodes); 845 kfree(c->jheads[i].log_hash); 846 } 847 kfree(c->jheads); 848 c->jheads = NULL; 849 } 850 } 851 852 /** 853 * free_orphans - free orphans. 854 * @c: UBIFS file-system description object 855 */ 856 static void free_orphans(struct ubifs_info *c) 857 { 858 struct ubifs_orphan *orph; 859 860 while (c->orph_dnext) { 861 orph = c->orph_dnext; 862 c->orph_dnext = orph->dnext; 863 list_del(&orph->list); 864 kfree(orph); 865 } 866 867 while (!list_empty(&c->orph_list)) { 868 orph = list_entry(c->orph_list.next, struct ubifs_orphan, list); 869 list_del(&orph->list); 870 kfree(orph); 871 ubifs_err(c, "orphan list not empty at unmount"); 872 } 873 874 vfree(c->orph_buf); 875 c->orph_buf = NULL; 876 } 877 878 /** 879 * free_buds - free per-bud objects. 880 * @c: UBIFS file-system description object 881 */ 882 static void free_buds(struct ubifs_info *c) 883 { 884 struct ubifs_bud *bud, *n; 885 886 rbtree_postorder_for_each_entry_safe(bud, n, &c->buds, rb) 887 kfree(bud); 888 } 889 890 /** 891 * check_volume_empty - check if the UBI volume is empty. 892 * @c: UBIFS file-system description object 893 * 894 * This function checks if the UBIFS volume is empty by looking if its LEBs are 895 * mapped or not. The result of checking is stored in the @c->empty variable. 896 * Returns zero in case of success and a negative error code in case of 897 * failure. 898 */ 899 static int check_volume_empty(struct ubifs_info *c) 900 { 901 int lnum, err; 902 903 c->empty = 1; 904 for (lnum = 0; lnum < c->leb_cnt; lnum++) { 905 err = ubifs_is_mapped(c, lnum); 906 if (unlikely(err < 0)) 907 return err; 908 if (err == 1) { 909 c->empty = 0; 910 break; 911 } 912 913 cond_resched(); 914 } 915 916 return 0; 917 } 918 919 /* 920 * UBIFS mount options. 921 * 922 * Opt_fast_unmount: do not run a journal commit before un-mounting 923 * Opt_norm_unmount: run a journal commit before un-mounting 924 * Opt_bulk_read: enable bulk-reads 925 * Opt_no_bulk_read: disable bulk-reads 926 * Opt_chk_data_crc: check CRCs when reading data nodes 927 * Opt_no_chk_data_crc: do not check CRCs when reading data nodes 928 * Opt_override_compr: override default compressor 929 * Opt_assert: set ubifs_assert() action 930 * Opt_auth_key: The key name used for authentication 931 * Opt_auth_hash_name: The hash type used for authentication 932 * Opt_err: just end of array marker 933 */ 934 enum { 935 Opt_fast_unmount, 936 Opt_norm_unmount, 937 Opt_bulk_read, 938 Opt_no_bulk_read, 939 Opt_chk_data_crc, 940 Opt_no_chk_data_crc, 941 Opt_override_compr, 942 Opt_assert, 943 Opt_auth_key, 944 Opt_auth_hash_name, 945 Opt_ignore, 946 Opt_err, 947 }; 948 949 static const match_table_t tokens = { 950 {Opt_fast_unmount, "fast_unmount"}, 951 {Opt_norm_unmount, "norm_unmount"}, 952 {Opt_bulk_read, "bulk_read"}, 953 {Opt_no_bulk_read, "no_bulk_read"}, 954 {Opt_chk_data_crc, "chk_data_crc"}, 955 {Opt_no_chk_data_crc, "no_chk_data_crc"}, 956 {Opt_override_compr, "compr=%s"}, 957 {Opt_auth_key, "auth_key=%s"}, 958 {Opt_auth_hash_name, "auth_hash_name=%s"}, 959 {Opt_ignore, "ubi=%s"}, 960 {Opt_ignore, "vol=%s"}, 961 {Opt_assert, "assert=%s"}, 962 {Opt_err, NULL}, 963 }; 964 965 /** 966 * parse_standard_option - parse a standard mount option. 967 * @option: the option to parse 968 * 969 * Normally, standard mount options like "sync" are passed to file-systems as 970 * flags. However, when a "rootflags=" kernel boot parameter is used, they may 971 * be present in the options string. This function tries to deal with this 972 * situation and parse standard options. Returns 0 if the option was not 973 * recognized, and the corresponding integer flag if it was. 974 * 975 * UBIFS is only interested in the "sync" option, so do not check for anything 976 * else. 977 */ 978 static int parse_standard_option(const char *option) 979 { 980 981 pr_notice("UBIFS: parse %s\n", option); 982 if (!strcmp(option, "sync")) 983 return SB_SYNCHRONOUS; 984 return 0; 985 } 986 987 /** 988 * ubifs_parse_options - parse mount parameters. 989 * @c: UBIFS file-system description object 990 * @options: parameters to parse 991 * @is_remount: non-zero if this is FS re-mount 992 * 993 * This function parses UBIFS mount options and returns zero in case success 994 * and a negative error code in case of failure. 995 */ 996 static int ubifs_parse_options(struct ubifs_info *c, char *options, 997 int is_remount) 998 { 999 char *p; 1000 substring_t args[MAX_OPT_ARGS]; 1001 1002 if (!options) 1003 return 0; 1004 1005 while ((p = strsep(&options, ","))) { 1006 int token; 1007 1008 if (!*p) 1009 continue; 1010 1011 token = match_token(p, tokens, args); 1012 switch (token) { 1013 /* 1014 * %Opt_fast_unmount and %Opt_norm_unmount options are ignored. 1015 * We accept them in order to be backward-compatible. But this 1016 * should be removed at some point. 1017 */ 1018 case Opt_fast_unmount: 1019 c->mount_opts.unmount_mode = 2; 1020 break; 1021 case Opt_norm_unmount: 1022 c->mount_opts.unmount_mode = 1; 1023 break; 1024 case Opt_bulk_read: 1025 c->mount_opts.bulk_read = 2; 1026 c->bulk_read = 1; 1027 break; 1028 case Opt_no_bulk_read: 1029 c->mount_opts.bulk_read = 1; 1030 c->bulk_read = 0; 1031 break; 1032 case Opt_chk_data_crc: 1033 c->mount_opts.chk_data_crc = 2; 1034 c->no_chk_data_crc = 0; 1035 break; 1036 case Opt_no_chk_data_crc: 1037 c->mount_opts.chk_data_crc = 1; 1038 c->no_chk_data_crc = 1; 1039 break; 1040 case Opt_override_compr: 1041 { 1042 char *name = match_strdup(&args[0]); 1043 1044 if (!name) 1045 return -ENOMEM; 1046 if (!strcmp(name, "none")) 1047 c->mount_opts.compr_type = UBIFS_COMPR_NONE; 1048 else if (!strcmp(name, "lzo")) 1049 c->mount_opts.compr_type = UBIFS_COMPR_LZO; 1050 else if (!strcmp(name, "zlib")) 1051 c->mount_opts.compr_type = UBIFS_COMPR_ZLIB; 1052 else if (!strcmp(name, "zstd")) 1053 c->mount_opts.compr_type = UBIFS_COMPR_ZSTD; 1054 else { 1055 ubifs_err(c, "unknown compressor \"%s\"", name); //FIXME: is c ready? 1056 kfree(name); 1057 return -EINVAL; 1058 } 1059 kfree(name); 1060 c->mount_opts.override_compr = 1; 1061 c->default_compr = c->mount_opts.compr_type; 1062 break; 1063 } 1064 case Opt_assert: 1065 { 1066 char *act = match_strdup(&args[0]); 1067 1068 if (!act) 1069 return -ENOMEM; 1070 if (!strcmp(act, "report")) 1071 c->assert_action = ASSACT_REPORT; 1072 else if (!strcmp(act, "read-only")) 1073 c->assert_action = ASSACT_RO; 1074 else if (!strcmp(act, "panic")) 1075 c->assert_action = ASSACT_PANIC; 1076 else { 1077 ubifs_err(c, "unknown assert action \"%s\"", act); 1078 kfree(act); 1079 return -EINVAL; 1080 } 1081 kfree(act); 1082 break; 1083 } 1084 case Opt_auth_key: 1085 c->auth_key_name = kstrdup(args[0].from, GFP_KERNEL); 1086 if (!c->auth_key_name) 1087 return -ENOMEM; 1088 break; 1089 case Opt_auth_hash_name: 1090 c->auth_hash_name = kstrdup(args[0].from, GFP_KERNEL); 1091 if (!c->auth_hash_name) 1092 return -ENOMEM; 1093 break; 1094 case Opt_ignore: 1095 break; 1096 default: 1097 { 1098 unsigned long flag; 1099 struct super_block *sb = c->vfs_sb; 1100 1101 flag = parse_standard_option(p); 1102 if (!flag) { 1103 ubifs_err(c, "unrecognized mount option \"%s\" or missing value", 1104 p); 1105 return -EINVAL; 1106 } 1107 sb->s_flags |= flag; 1108 break; 1109 } 1110 } 1111 } 1112 1113 return 0; 1114 } 1115 1116 /** 1117 * destroy_journal - destroy journal data structures. 1118 * @c: UBIFS file-system description object 1119 * 1120 * This function destroys journal data structures including those that may have 1121 * been created by recovery functions. 1122 */ 1123 static void destroy_journal(struct ubifs_info *c) 1124 { 1125 while (!list_empty(&c->unclean_leb_list)) { 1126 struct ubifs_unclean_leb *ucleb; 1127 1128 ucleb = list_entry(c->unclean_leb_list.next, 1129 struct ubifs_unclean_leb, list); 1130 list_del(&ucleb->list); 1131 kfree(ucleb); 1132 } 1133 while (!list_empty(&c->old_buds)) { 1134 struct ubifs_bud *bud; 1135 1136 bud = list_entry(c->old_buds.next, struct ubifs_bud, list); 1137 list_del(&bud->list); 1138 kfree(bud); 1139 } 1140 ubifs_destroy_idx_gc(c); 1141 ubifs_destroy_size_tree(c); 1142 ubifs_tnc_close(c); 1143 free_buds(c); 1144 } 1145 1146 /** 1147 * bu_init - initialize bulk-read information. 1148 * @c: UBIFS file-system description object 1149 */ 1150 static void bu_init(struct ubifs_info *c) 1151 { 1152 ubifs_assert(c, c->bulk_read == 1); 1153 1154 if (c->bu.buf) 1155 return; /* Already initialized */ 1156 1157 again: 1158 c->bu.buf = kmalloc(c->max_bu_buf_len, GFP_KERNEL | __GFP_NOWARN); 1159 if (!c->bu.buf) { 1160 if (c->max_bu_buf_len > UBIFS_KMALLOC_OK) { 1161 c->max_bu_buf_len = UBIFS_KMALLOC_OK; 1162 goto again; 1163 } 1164 1165 /* Just disable bulk-read */ 1166 ubifs_warn(c, "cannot allocate %d bytes of memory for bulk-read, disabling it", 1167 c->max_bu_buf_len); 1168 c->mount_opts.bulk_read = 1; 1169 c->bulk_read = 0; 1170 return; 1171 } 1172 } 1173 1174 /** 1175 * check_free_space - check if there is enough free space to mount. 1176 * @c: UBIFS file-system description object 1177 * 1178 * This function makes sure UBIFS has enough free space to be mounted in 1179 * read/write mode. UBIFS must always have some free space to allow deletions. 1180 */ 1181 static int check_free_space(struct ubifs_info *c) 1182 { 1183 ubifs_assert(c, c->dark_wm > 0); 1184 if (c->lst.total_free + c->lst.total_dirty < c->dark_wm) { 1185 ubifs_err(c, "insufficient free space to mount in R/W mode"); 1186 ubifs_dump_budg(c, &c->bi); 1187 ubifs_dump_lprops(c); 1188 return -ENOSPC; 1189 } 1190 return 0; 1191 } 1192 1193 /** 1194 * mount_ubifs - mount UBIFS file-system. 1195 * @c: UBIFS file-system description object 1196 * 1197 * This function mounts UBIFS file system. Returns zero in case of success and 1198 * a negative error code in case of failure. 1199 */ 1200 static int mount_ubifs(struct ubifs_info *c) 1201 { 1202 int err; 1203 long long x, y; 1204 size_t sz; 1205 1206 c->ro_mount = !!sb_rdonly(c->vfs_sb); 1207 /* Suppress error messages while probing if SB_SILENT is set */ 1208 c->probing = !!(c->vfs_sb->s_flags & SB_SILENT); 1209 1210 err = init_constants_early(c); 1211 if (err) 1212 return err; 1213 1214 err = ubifs_debugging_init(c); 1215 if (err) 1216 return err; 1217 1218 err = check_volume_empty(c); 1219 if (err) 1220 goto out_free; 1221 1222 if (c->empty && (c->ro_mount || c->ro_media)) { 1223 /* 1224 * This UBI volume is empty, and read-only, or the file system 1225 * is mounted read-only - we cannot format it. 1226 */ 1227 ubifs_err(c, "can't format empty UBI volume: read-only %s", 1228 c->ro_media ? "UBI volume" : "mount"); 1229 err = -EROFS; 1230 goto out_free; 1231 } 1232 1233 if (c->ro_media && !c->ro_mount) { 1234 ubifs_err(c, "cannot mount read-write - read-only media"); 1235 err = -EROFS; 1236 goto out_free; 1237 } 1238 1239 /* 1240 * The requirement for the buffer is that it should fit indexing B-tree 1241 * height amount of integers. We assume the height if the TNC tree will 1242 * never exceed 64. 1243 */ 1244 err = -ENOMEM; 1245 c->bottom_up_buf = kmalloc_array(BOTTOM_UP_HEIGHT, sizeof(int), 1246 GFP_KERNEL); 1247 if (!c->bottom_up_buf) 1248 goto out_free; 1249 1250 c->sbuf = vmalloc(c->leb_size); 1251 if (!c->sbuf) 1252 goto out_free; 1253 1254 if (!c->ro_mount) { 1255 c->ileb_buf = vmalloc(c->leb_size); 1256 if (!c->ileb_buf) 1257 goto out_free; 1258 } 1259 1260 if (c->bulk_read == 1) 1261 bu_init(c); 1262 1263 if (!c->ro_mount) { 1264 c->write_reserve_buf = kmalloc(COMPRESSED_DATA_NODE_BUF_SZ + \ 1265 UBIFS_CIPHER_BLOCK_SIZE, 1266 GFP_KERNEL); 1267 if (!c->write_reserve_buf) 1268 goto out_free; 1269 } 1270 1271 c->mounting = 1; 1272 1273 if (c->auth_key_name) { 1274 if (IS_ENABLED(CONFIG_UBIFS_FS_AUTHENTICATION)) { 1275 err = ubifs_init_authentication(c); 1276 if (err) 1277 goto out_free; 1278 } else { 1279 ubifs_err(c, "auth_key_name, but UBIFS is built without" 1280 " authentication support"); 1281 err = -EINVAL; 1282 goto out_free; 1283 } 1284 } 1285 1286 err = ubifs_read_superblock(c); 1287 if (err) 1288 goto out_free; 1289 1290 c->probing = 0; 1291 1292 /* 1293 * Make sure the compressor which is set as default in the superblock 1294 * or overridden by mount options is actually compiled in. 1295 */ 1296 if (!ubifs_compr_present(c, c->default_compr)) { 1297 ubifs_err(c, "'compressor \"%s\" is not compiled in", 1298 ubifs_compr_name(c, c->default_compr)); 1299 err = -ENOTSUPP; 1300 goto out_free; 1301 } 1302 1303 err = init_constants_sb(c); 1304 if (err) 1305 goto out_free; 1306 1307 sz = ALIGN(c->max_idx_node_sz, c->min_io_size) * 2; 1308 c->cbuf = kmalloc(sz, GFP_NOFS); 1309 if (!c->cbuf) { 1310 err = -ENOMEM; 1311 goto out_free; 1312 } 1313 1314 err = alloc_wbufs(c); 1315 if (err) 1316 goto out_cbuf; 1317 1318 sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num, c->vi.vol_id); 1319 if (!c->ro_mount) { 1320 /* Create background thread */ 1321 c->bgt = kthread_create(ubifs_bg_thread, c, "%s", c->bgt_name); 1322 if (IS_ERR(c->bgt)) { 1323 err = PTR_ERR(c->bgt); 1324 c->bgt = NULL; 1325 ubifs_err(c, "cannot spawn \"%s\", error %d", 1326 c->bgt_name, err); 1327 goto out_wbufs; 1328 } 1329 wake_up_process(c->bgt); 1330 } 1331 1332 err = ubifs_read_master(c); 1333 if (err) 1334 goto out_master; 1335 1336 init_constants_master(c); 1337 1338 if ((c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY)) != 0) { 1339 ubifs_msg(c, "recovery needed"); 1340 c->need_recovery = 1; 1341 } 1342 1343 if (c->need_recovery && !c->ro_mount) { 1344 err = ubifs_recover_inl_heads(c, c->sbuf); 1345 if (err) 1346 goto out_master; 1347 } 1348 1349 err = ubifs_lpt_init(c, 1, !c->ro_mount); 1350 if (err) 1351 goto out_master; 1352 1353 if (!c->ro_mount && c->space_fixup) { 1354 err = ubifs_fixup_free_space(c); 1355 if (err) 1356 goto out_lpt; 1357 } 1358 1359 if (!c->ro_mount && !c->need_recovery) { 1360 /* 1361 * Set the "dirty" flag so that if we reboot uncleanly we 1362 * will notice this immediately on the next mount. 1363 */ 1364 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY); 1365 err = ubifs_write_master(c); 1366 if (err) 1367 goto out_lpt; 1368 } 1369 1370 /* 1371 * Handle offline signed images: Now that the master node is 1372 * written and its validation no longer depends on the hash 1373 * in the superblock, we can update the offline signed 1374 * superblock with a HMAC version, 1375 */ 1376 if (ubifs_authenticated(c) && ubifs_hmac_zero(c, c->sup_node->hmac)) { 1377 err = ubifs_hmac_wkm(c, c->sup_node->hmac_wkm); 1378 if (err) 1379 goto out_lpt; 1380 c->superblock_need_write = 1; 1381 } 1382 1383 if (!c->ro_mount && c->superblock_need_write) { 1384 err = ubifs_write_sb_node(c, c->sup_node); 1385 if (err) 1386 goto out_lpt; 1387 c->superblock_need_write = 0; 1388 } 1389 1390 err = dbg_check_idx_size(c, c->bi.old_idx_sz); 1391 if (err) 1392 goto out_lpt; 1393 1394 err = ubifs_replay_journal(c); 1395 if (err) 1396 goto out_journal; 1397 1398 /* Calculate 'min_idx_lebs' after journal replay */ 1399 c->bi.min_idx_lebs = ubifs_calc_min_idx_lebs(c); 1400 1401 err = ubifs_mount_orphans(c, c->need_recovery, c->ro_mount); 1402 if (err) 1403 goto out_orphans; 1404 1405 if (!c->ro_mount) { 1406 int lnum; 1407 1408 err = check_free_space(c); 1409 if (err) 1410 goto out_orphans; 1411 1412 /* Check for enough log space */ 1413 lnum = c->lhead_lnum + 1; 1414 if (lnum >= UBIFS_LOG_LNUM + c->log_lebs) 1415 lnum = UBIFS_LOG_LNUM; 1416 if (lnum == c->ltail_lnum) { 1417 err = ubifs_consolidate_log(c); 1418 if (err) 1419 goto out_orphans; 1420 } 1421 1422 if (c->need_recovery) { 1423 if (!ubifs_authenticated(c)) { 1424 err = ubifs_recover_size(c, true); 1425 if (err) 1426 goto out_orphans; 1427 } 1428 1429 err = ubifs_rcvry_gc_commit(c); 1430 if (err) 1431 goto out_orphans; 1432 1433 if (ubifs_authenticated(c)) { 1434 err = ubifs_recover_size(c, false); 1435 if (err) 1436 goto out_orphans; 1437 } 1438 } else { 1439 err = take_gc_lnum(c); 1440 if (err) 1441 goto out_orphans; 1442 1443 /* 1444 * GC LEB may contain garbage if there was an unclean 1445 * reboot, and it should be un-mapped. 1446 */ 1447 err = ubifs_leb_unmap(c, c->gc_lnum); 1448 if (err) 1449 goto out_orphans; 1450 } 1451 1452 err = dbg_check_lprops(c); 1453 if (err) 1454 goto out_orphans; 1455 } else if (c->need_recovery) { 1456 err = ubifs_recover_size(c, false); 1457 if (err) 1458 goto out_orphans; 1459 } else { 1460 /* 1461 * Even if we mount read-only, we have to set space in GC LEB 1462 * to proper value because this affects UBIFS free space 1463 * reporting. We do not want to have a situation when 1464 * re-mounting from R/O to R/W changes amount of free space. 1465 */ 1466 err = take_gc_lnum(c); 1467 if (err) 1468 goto out_orphans; 1469 } 1470 1471 spin_lock(&ubifs_infos_lock); 1472 list_add_tail(&c->infos_list, &ubifs_infos); 1473 spin_unlock(&ubifs_infos_lock); 1474 1475 if (c->need_recovery) { 1476 if (c->ro_mount) 1477 ubifs_msg(c, "recovery deferred"); 1478 else { 1479 c->need_recovery = 0; 1480 ubifs_msg(c, "recovery completed"); 1481 /* 1482 * GC LEB has to be empty and taken at this point. But 1483 * the journal head LEBs may also be accounted as 1484 * "empty taken" if they are empty. 1485 */ 1486 ubifs_assert(c, c->lst.taken_empty_lebs > 0); 1487 } 1488 } else 1489 ubifs_assert(c, c->lst.taken_empty_lebs > 0); 1490 1491 err = dbg_check_filesystem(c); 1492 if (err) 1493 goto out_infos; 1494 1495 dbg_debugfs_init_fs(c); 1496 1497 c->mounting = 0; 1498 1499 ubifs_msg(c, "UBIFS: mounted UBI device %d, volume %d, name \"%s\"%s", 1500 c->vi.ubi_num, c->vi.vol_id, c->vi.name, 1501 c->ro_mount ? ", R/O mode" : ""); 1502 x = (long long)c->main_lebs * c->leb_size; 1503 y = (long long)c->log_lebs * c->leb_size + c->max_bud_bytes; 1504 ubifs_msg(c, "LEB size: %d bytes (%d KiB), min./max. I/O unit sizes: %d bytes/%d bytes", 1505 c->leb_size, c->leb_size >> 10, c->min_io_size, 1506 c->max_write_size); 1507 ubifs_msg(c, "FS size: %lld bytes (%lld MiB, %d LEBs), journal size %lld bytes (%lld MiB, %d LEBs)", 1508 x, x >> 20, c->main_lebs, 1509 y, y >> 20, c->log_lebs + c->max_bud_cnt); 1510 ubifs_msg(c, "reserved for root: %llu bytes (%llu KiB)", 1511 c->report_rp_size, c->report_rp_size >> 10); 1512 ubifs_msg(c, "media format: w%d/r%d (latest is w%d/r%d), UUID %pUB%s", 1513 c->fmt_version, c->ro_compat_version, 1514 UBIFS_FORMAT_VERSION, UBIFS_RO_COMPAT_VERSION, c->uuid, 1515 c->big_lpt ? ", big LPT model" : ", small LPT model"); 1516 1517 dbg_gen("default compressor: %s", ubifs_compr_name(c, c->default_compr)); 1518 dbg_gen("data journal heads: %d", 1519 c->jhead_cnt - NONDATA_JHEADS_CNT); 1520 dbg_gen("log LEBs: %d (%d - %d)", 1521 c->log_lebs, UBIFS_LOG_LNUM, c->log_last); 1522 dbg_gen("LPT area LEBs: %d (%d - %d)", 1523 c->lpt_lebs, c->lpt_first, c->lpt_last); 1524 dbg_gen("orphan area LEBs: %d (%d - %d)", 1525 c->orph_lebs, c->orph_first, c->orph_last); 1526 dbg_gen("main area LEBs: %d (%d - %d)", 1527 c->main_lebs, c->main_first, c->leb_cnt - 1); 1528 dbg_gen("index LEBs: %d", c->lst.idx_lebs); 1529 dbg_gen("total index bytes: %lld (%lld KiB, %lld MiB)", 1530 c->bi.old_idx_sz, c->bi.old_idx_sz >> 10, 1531 c->bi.old_idx_sz >> 20); 1532 dbg_gen("key hash type: %d", c->key_hash_type); 1533 dbg_gen("tree fanout: %d", c->fanout); 1534 dbg_gen("reserved GC LEB: %d", c->gc_lnum); 1535 dbg_gen("max. znode size %d", c->max_znode_sz); 1536 dbg_gen("max. index node size %d", c->max_idx_node_sz); 1537 dbg_gen("node sizes: data %zu, inode %zu, dentry %zu", 1538 UBIFS_DATA_NODE_SZ, UBIFS_INO_NODE_SZ, UBIFS_DENT_NODE_SZ); 1539 dbg_gen("node sizes: trun %zu, sb %zu, master %zu", 1540 UBIFS_TRUN_NODE_SZ, UBIFS_SB_NODE_SZ, UBIFS_MST_NODE_SZ); 1541 dbg_gen("node sizes: ref %zu, cmt. start %zu, orph %zu", 1542 UBIFS_REF_NODE_SZ, UBIFS_CS_NODE_SZ, UBIFS_ORPH_NODE_SZ); 1543 dbg_gen("max. node sizes: data %zu, inode %zu dentry %zu, idx %d", 1544 UBIFS_MAX_DATA_NODE_SZ, UBIFS_MAX_INO_NODE_SZ, 1545 UBIFS_MAX_DENT_NODE_SZ, ubifs_idx_node_sz(c, c->fanout)); 1546 dbg_gen("dead watermark: %d", c->dead_wm); 1547 dbg_gen("dark watermark: %d", c->dark_wm); 1548 dbg_gen("LEB overhead: %d", c->leb_overhead); 1549 x = (long long)c->main_lebs * c->dark_wm; 1550 dbg_gen("max. dark space: %lld (%lld KiB, %lld MiB)", 1551 x, x >> 10, x >> 20); 1552 dbg_gen("maximum bud bytes: %lld (%lld KiB, %lld MiB)", 1553 c->max_bud_bytes, c->max_bud_bytes >> 10, 1554 c->max_bud_bytes >> 20); 1555 dbg_gen("BG commit bud bytes: %lld (%lld KiB, %lld MiB)", 1556 c->bg_bud_bytes, c->bg_bud_bytes >> 10, 1557 c->bg_bud_bytes >> 20); 1558 dbg_gen("current bud bytes %lld (%lld KiB, %lld MiB)", 1559 c->bud_bytes, c->bud_bytes >> 10, c->bud_bytes >> 20); 1560 dbg_gen("max. seq. number: %llu", c->max_sqnum); 1561 dbg_gen("commit number: %llu", c->cmt_no); 1562 dbg_gen("max. xattrs per inode: %d", ubifs_xattr_max_cnt(c)); 1563 dbg_gen("max orphans: %d", c->max_orphans); 1564 1565 return 0; 1566 1567 out_infos: 1568 spin_lock(&ubifs_infos_lock); 1569 list_del(&c->infos_list); 1570 spin_unlock(&ubifs_infos_lock); 1571 out_orphans: 1572 free_orphans(c); 1573 out_journal: 1574 destroy_journal(c); 1575 out_lpt: 1576 ubifs_lpt_free(c, 0); 1577 out_master: 1578 kfree(c->mst_node); 1579 kfree(c->rcvrd_mst_node); 1580 if (c->bgt) 1581 kthread_stop(c->bgt); 1582 out_wbufs: 1583 free_wbufs(c); 1584 out_cbuf: 1585 kfree(c->cbuf); 1586 out_free: 1587 kfree(c->write_reserve_buf); 1588 kfree(c->bu.buf); 1589 vfree(c->ileb_buf); 1590 vfree(c->sbuf); 1591 kfree(c->bottom_up_buf); 1592 ubifs_debugging_exit(c); 1593 return err; 1594 } 1595 1596 /** 1597 * ubifs_umount - un-mount UBIFS file-system. 1598 * @c: UBIFS file-system description object 1599 * 1600 * Note, this function is called to free allocated resourced when un-mounting, 1601 * as well as free resources when an error occurred while we were half way 1602 * through mounting (error path cleanup function). So it has to make sure the 1603 * resource was actually allocated before freeing it. 1604 */ 1605 static void ubifs_umount(struct ubifs_info *c) 1606 { 1607 dbg_gen("un-mounting UBI device %d, volume %d", c->vi.ubi_num, 1608 c->vi.vol_id); 1609 1610 dbg_debugfs_exit_fs(c); 1611 spin_lock(&ubifs_infos_lock); 1612 list_del(&c->infos_list); 1613 spin_unlock(&ubifs_infos_lock); 1614 1615 if (c->bgt) 1616 kthread_stop(c->bgt); 1617 1618 destroy_journal(c); 1619 free_wbufs(c); 1620 free_orphans(c); 1621 ubifs_lpt_free(c, 0); 1622 ubifs_exit_authentication(c); 1623 1624 kfree(c->auth_key_name); 1625 kfree(c->auth_hash_name); 1626 kfree(c->cbuf); 1627 kfree(c->rcvrd_mst_node); 1628 kfree(c->mst_node); 1629 kfree(c->write_reserve_buf); 1630 kfree(c->bu.buf); 1631 vfree(c->ileb_buf); 1632 vfree(c->sbuf); 1633 kfree(c->bottom_up_buf); 1634 ubifs_debugging_exit(c); 1635 } 1636 1637 /** 1638 * ubifs_remount_rw - re-mount in read-write mode. 1639 * @c: UBIFS file-system description object 1640 * 1641 * UBIFS avoids allocating many unnecessary resources when mounted in read-only 1642 * mode. This function allocates the needed resources and re-mounts UBIFS in 1643 * read-write mode. 1644 */ 1645 static int ubifs_remount_rw(struct ubifs_info *c) 1646 { 1647 int err, lnum; 1648 1649 if (c->rw_incompat) { 1650 ubifs_err(c, "the file-system is not R/W-compatible"); 1651 ubifs_msg(c, "on-flash format version is w%d/r%d, but software only supports up to version w%d/r%d", 1652 c->fmt_version, c->ro_compat_version, 1653 UBIFS_FORMAT_VERSION, UBIFS_RO_COMPAT_VERSION); 1654 return -EROFS; 1655 } 1656 1657 mutex_lock(&c->umount_mutex); 1658 dbg_save_space_info(c); 1659 c->remounting_rw = 1; 1660 c->ro_mount = 0; 1661 1662 if (c->space_fixup) { 1663 err = ubifs_fixup_free_space(c); 1664 if (err) 1665 goto out; 1666 } 1667 1668 err = check_free_space(c); 1669 if (err) 1670 goto out; 1671 1672 if (c->need_recovery) { 1673 ubifs_msg(c, "completing deferred recovery"); 1674 err = ubifs_write_rcvrd_mst_node(c); 1675 if (err) 1676 goto out; 1677 if (!ubifs_authenticated(c)) { 1678 err = ubifs_recover_size(c, true); 1679 if (err) 1680 goto out; 1681 } 1682 err = ubifs_clean_lebs(c, c->sbuf); 1683 if (err) 1684 goto out; 1685 err = ubifs_recover_inl_heads(c, c->sbuf); 1686 if (err) 1687 goto out; 1688 } else { 1689 /* A readonly mount is not allowed to have orphans */ 1690 ubifs_assert(c, c->tot_orphans == 0); 1691 err = ubifs_clear_orphans(c); 1692 if (err) 1693 goto out; 1694 } 1695 1696 if (!(c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY))) { 1697 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY); 1698 err = ubifs_write_master(c); 1699 if (err) 1700 goto out; 1701 } 1702 1703 if (c->superblock_need_write) { 1704 struct ubifs_sb_node *sup = c->sup_node; 1705 1706 err = ubifs_write_sb_node(c, sup); 1707 if (err) 1708 goto out; 1709 1710 c->superblock_need_write = 0; 1711 } 1712 1713 c->ileb_buf = vmalloc(c->leb_size); 1714 if (!c->ileb_buf) { 1715 err = -ENOMEM; 1716 goto out; 1717 } 1718 1719 c->write_reserve_buf = kmalloc(COMPRESSED_DATA_NODE_BUF_SZ + \ 1720 UBIFS_CIPHER_BLOCK_SIZE, GFP_KERNEL); 1721 if (!c->write_reserve_buf) { 1722 err = -ENOMEM; 1723 goto out; 1724 } 1725 1726 err = ubifs_lpt_init(c, 0, 1); 1727 if (err) 1728 goto out; 1729 1730 /* Create background thread */ 1731 c->bgt = kthread_create(ubifs_bg_thread, c, "%s", c->bgt_name); 1732 if (IS_ERR(c->bgt)) { 1733 err = PTR_ERR(c->bgt); 1734 c->bgt = NULL; 1735 ubifs_err(c, "cannot spawn \"%s\", error %d", 1736 c->bgt_name, err); 1737 goto out; 1738 } 1739 wake_up_process(c->bgt); 1740 1741 c->orph_buf = vmalloc(c->leb_size); 1742 if (!c->orph_buf) { 1743 err = -ENOMEM; 1744 goto out; 1745 } 1746 1747 /* Check for enough log space */ 1748 lnum = c->lhead_lnum + 1; 1749 if (lnum >= UBIFS_LOG_LNUM + c->log_lebs) 1750 lnum = UBIFS_LOG_LNUM; 1751 if (lnum == c->ltail_lnum) { 1752 err = ubifs_consolidate_log(c); 1753 if (err) 1754 goto out; 1755 } 1756 1757 if (c->need_recovery) { 1758 err = ubifs_rcvry_gc_commit(c); 1759 if (err) 1760 goto out; 1761 1762 if (ubifs_authenticated(c)) { 1763 err = ubifs_recover_size(c, false); 1764 if (err) 1765 goto out; 1766 } 1767 } else { 1768 err = ubifs_leb_unmap(c, c->gc_lnum); 1769 } 1770 if (err) 1771 goto out; 1772 1773 dbg_gen("re-mounted read-write"); 1774 c->remounting_rw = 0; 1775 1776 if (c->need_recovery) { 1777 c->need_recovery = 0; 1778 ubifs_msg(c, "deferred recovery completed"); 1779 } else { 1780 /* 1781 * Do not run the debugging space check if the were doing 1782 * recovery, because when we saved the information we had the 1783 * file-system in a state where the TNC and lprops has been 1784 * modified in memory, but all the I/O operations (including a 1785 * commit) were deferred. So the file-system was in 1786 * "non-committed" state. Now the file-system is in committed 1787 * state, and of course the amount of free space will change 1788 * because, for example, the old index size was imprecise. 1789 */ 1790 err = dbg_check_space_info(c); 1791 } 1792 1793 mutex_unlock(&c->umount_mutex); 1794 return err; 1795 1796 out: 1797 c->ro_mount = 1; 1798 vfree(c->orph_buf); 1799 c->orph_buf = NULL; 1800 if (c->bgt) { 1801 kthread_stop(c->bgt); 1802 c->bgt = NULL; 1803 } 1804 free_wbufs(c); 1805 kfree(c->write_reserve_buf); 1806 c->write_reserve_buf = NULL; 1807 vfree(c->ileb_buf); 1808 c->ileb_buf = NULL; 1809 ubifs_lpt_free(c, 1); 1810 c->remounting_rw = 0; 1811 mutex_unlock(&c->umount_mutex); 1812 return err; 1813 } 1814 1815 /** 1816 * ubifs_remount_ro - re-mount in read-only mode. 1817 * @c: UBIFS file-system description object 1818 * 1819 * We assume VFS has stopped writing. Possibly the background thread could be 1820 * running a commit, however kthread_stop will wait in that case. 1821 */ 1822 static void ubifs_remount_ro(struct ubifs_info *c) 1823 { 1824 int i, err; 1825 1826 ubifs_assert(c, !c->need_recovery); 1827 ubifs_assert(c, !c->ro_mount); 1828 1829 mutex_lock(&c->umount_mutex); 1830 if (c->bgt) { 1831 kthread_stop(c->bgt); 1832 c->bgt = NULL; 1833 } 1834 1835 dbg_save_space_info(c); 1836 1837 for (i = 0; i < c->jhead_cnt; i++) { 1838 err = ubifs_wbuf_sync(&c->jheads[i].wbuf); 1839 if (err) 1840 ubifs_ro_mode(c, err); 1841 } 1842 1843 c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY); 1844 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS); 1845 c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum); 1846 err = ubifs_write_master(c); 1847 if (err) 1848 ubifs_ro_mode(c, err); 1849 1850 vfree(c->orph_buf); 1851 c->orph_buf = NULL; 1852 kfree(c->write_reserve_buf); 1853 c->write_reserve_buf = NULL; 1854 vfree(c->ileb_buf); 1855 c->ileb_buf = NULL; 1856 ubifs_lpt_free(c, 1); 1857 c->ro_mount = 1; 1858 err = dbg_check_space_info(c); 1859 if (err) 1860 ubifs_ro_mode(c, err); 1861 mutex_unlock(&c->umount_mutex); 1862 } 1863 1864 static void ubifs_put_super(struct super_block *sb) 1865 { 1866 int i; 1867 struct ubifs_info *c = sb->s_fs_info; 1868 1869 ubifs_msg(c, "un-mount UBI device %d", c->vi.ubi_num); 1870 1871 /* 1872 * The following asserts are only valid if there has not been a failure 1873 * of the media. For example, there will be dirty inodes if we failed 1874 * to write them back because of I/O errors. 1875 */ 1876 if (!c->ro_error) { 1877 ubifs_assert(c, c->bi.idx_growth == 0); 1878 ubifs_assert(c, c->bi.dd_growth == 0); 1879 ubifs_assert(c, c->bi.data_growth == 0); 1880 } 1881 1882 /* 1883 * The 'c->umount_lock' prevents races between UBIFS memory shrinker 1884 * and file system un-mount. Namely, it prevents the shrinker from 1885 * picking this superblock for shrinking - it will be just skipped if 1886 * the mutex is locked. 1887 */ 1888 mutex_lock(&c->umount_mutex); 1889 if (!c->ro_mount) { 1890 /* 1891 * First of all kill the background thread to make sure it does 1892 * not interfere with un-mounting and freeing resources. 1893 */ 1894 if (c->bgt) { 1895 kthread_stop(c->bgt); 1896 c->bgt = NULL; 1897 } 1898 1899 /* 1900 * On fatal errors c->ro_error is set to 1, in which case we do 1901 * not write the master node. 1902 */ 1903 if (!c->ro_error) { 1904 int err; 1905 1906 /* Synchronize write-buffers */ 1907 for (i = 0; i < c->jhead_cnt; i++) { 1908 err = ubifs_wbuf_sync(&c->jheads[i].wbuf); 1909 if (err) 1910 ubifs_ro_mode(c, err); 1911 } 1912 1913 /* 1914 * We are being cleanly unmounted which means the 1915 * orphans were killed - indicate this in the master 1916 * node. Also save the reserved GC LEB number. 1917 */ 1918 c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY); 1919 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS); 1920 c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum); 1921 err = ubifs_write_master(c); 1922 if (err) 1923 /* 1924 * Recovery will attempt to fix the master area 1925 * next mount, so we just print a message and 1926 * continue to unmount normally. 1927 */ 1928 ubifs_err(c, "failed to write master node, error %d", 1929 err); 1930 } else { 1931 for (i = 0; i < c->jhead_cnt; i++) 1932 /* Make sure write-buffer timers are canceled */ 1933 hrtimer_cancel(&c->jheads[i].wbuf.timer); 1934 } 1935 } 1936 1937 ubifs_umount(c); 1938 ubi_close_volume(c->ubi); 1939 mutex_unlock(&c->umount_mutex); 1940 } 1941 1942 static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data) 1943 { 1944 int err; 1945 struct ubifs_info *c = sb->s_fs_info; 1946 1947 sync_filesystem(sb); 1948 dbg_gen("old flags %#lx, new flags %#x", sb->s_flags, *flags); 1949 1950 err = ubifs_parse_options(c, data, 1); 1951 if (err) { 1952 ubifs_err(c, "invalid or unknown remount parameter"); 1953 return err; 1954 } 1955 1956 if (c->ro_mount && !(*flags & SB_RDONLY)) { 1957 if (c->ro_error) { 1958 ubifs_msg(c, "cannot re-mount R/W due to prior errors"); 1959 return -EROFS; 1960 } 1961 if (c->ro_media) { 1962 ubifs_msg(c, "cannot re-mount R/W - UBI volume is R/O"); 1963 return -EROFS; 1964 } 1965 err = ubifs_remount_rw(c); 1966 if (err) 1967 return err; 1968 } else if (!c->ro_mount && (*flags & SB_RDONLY)) { 1969 if (c->ro_error) { 1970 ubifs_msg(c, "cannot re-mount R/O due to prior errors"); 1971 return -EROFS; 1972 } 1973 ubifs_remount_ro(c); 1974 } 1975 1976 if (c->bulk_read == 1) 1977 bu_init(c); 1978 else { 1979 dbg_gen("disable bulk-read"); 1980 mutex_lock(&c->bu_mutex); 1981 kfree(c->bu.buf); 1982 c->bu.buf = NULL; 1983 mutex_unlock(&c->bu_mutex); 1984 } 1985 1986 if (!c->need_recovery) 1987 ubifs_assert(c, c->lst.taken_empty_lebs > 0); 1988 1989 return 0; 1990 } 1991 1992 const struct super_operations ubifs_super_operations = { 1993 .alloc_inode = ubifs_alloc_inode, 1994 .free_inode = ubifs_free_inode, 1995 .put_super = ubifs_put_super, 1996 .write_inode = ubifs_write_inode, 1997 .evict_inode = ubifs_evict_inode, 1998 .statfs = ubifs_statfs, 1999 .dirty_inode = ubifs_dirty_inode, 2000 .remount_fs = ubifs_remount_fs, 2001 .show_options = ubifs_show_options, 2002 .sync_fs = ubifs_sync_fs, 2003 }; 2004 2005 /** 2006 * open_ubi - parse UBI device name string and open the UBI device. 2007 * @name: UBI volume name 2008 * @mode: UBI volume open mode 2009 * 2010 * The primary method of mounting UBIFS is by specifying the UBI volume 2011 * character device node path. However, UBIFS may also be mounted withoug any 2012 * character device node using one of the following methods: 2013 * 2014 * o ubiX_Y - mount UBI device number X, volume Y; 2015 * o ubiY - mount UBI device number 0, volume Y; 2016 * o ubiX:NAME - mount UBI device X, volume with name NAME; 2017 * o ubi:NAME - mount UBI device 0, volume with name NAME. 2018 * 2019 * Alternative '!' separator may be used instead of ':' (because some shells 2020 * like busybox may interpret ':' as an NFS host name separator). This function 2021 * returns UBI volume description object in case of success and a negative 2022 * error code in case of failure. 2023 */ 2024 static struct ubi_volume_desc *open_ubi(const char *name, int mode) 2025 { 2026 struct ubi_volume_desc *ubi; 2027 int dev, vol; 2028 char *endptr; 2029 2030 if (!name || !*name) 2031 return ERR_PTR(-EINVAL); 2032 2033 /* First, try to open using the device node path method */ 2034 ubi = ubi_open_volume_path(name, mode); 2035 if (!IS_ERR(ubi)) 2036 return ubi; 2037 2038 /* Try the "nodev" method */ 2039 if (name[0] != 'u' || name[1] != 'b' || name[2] != 'i') 2040 return ERR_PTR(-EINVAL); 2041 2042 /* ubi:NAME method */ 2043 if ((name[3] == ':' || name[3] == '!') && name[4] != '\0') 2044 return ubi_open_volume_nm(0, name + 4, mode); 2045 2046 if (!isdigit(name[3])) 2047 return ERR_PTR(-EINVAL); 2048 2049 dev = simple_strtoul(name + 3, &endptr, 0); 2050 2051 /* ubiY method */ 2052 if (*endptr == '\0') 2053 return ubi_open_volume(0, dev, mode); 2054 2055 /* ubiX_Y method */ 2056 if (*endptr == '_' && isdigit(endptr[1])) { 2057 vol = simple_strtoul(endptr + 1, &endptr, 0); 2058 if (*endptr != '\0') 2059 return ERR_PTR(-EINVAL); 2060 return ubi_open_volume(dev, vol, mode); 2061 } 2062 2063 /* ubiX:NAME method */ 2064 if ((*endptr == ':' || *endptr == '!') && endptr[1] != '\0') 2065 return ubi_open_volume_nm(dev, ++endptr, mode); 2066 2067 return ERR_PTR(-EINVAL); 2068 } 2069 2070 static struct ubifs_info *alloc_ubifs_info(struct ubi_volume_desc *ubi) 2071 { 2072 struct ubifs_info *c; 2073 2074 c = kzalloc(sizeof(struct ubifs_info), GFP_KERNEL); 2075 if (c) { 2076 spin_lock_init(&c->cnt_lock); 2077 spin_lock_init(&c->cs_lock); 2078 spin_lock_init(&c->buds_lock); 2079 spin_lock_init(&c->space_lock); 2080 spin_lock_init(&c->orphan_lock); 2081 init_rwsem(&c->commit_sem); 2082 mutex_init(&c->lp_mutex); 2083 mutex_init(&c->tnc_mutex); 2084 mutex_init(&c->log_mutex); 2085 mutex_init(&c->umount_mutex); 2086 mutex_init(&c->bu_mutex); 2087 mutex_init(&c->write_reserve_mutex); 2088 init_waitqueue_head(&c->cmt_wq); 2089 c->buds = RB_ROOT; 2090 c->old_idx = RB_ROOT; 2091 c->size_tree = RB_ROOT; 2092 c->orph_tree = RB_ROOT; 2093 INIT_LIST_HEAD(&c->infos_list); 2094 INIT_LIST_HEAD(&c->idx_gc); 2095 INIT_LIST_HEAD(&c->replay_list); 2096 INIT_LIST_HEAD(&c->replay_buds); 2097 INIT_LIST_HEAD(&c->uncat_list); 2098 INIT_LIST_HEAD(&c->empty_list); 2099 INIT_LIST_HEAD(&c->freeable_list); 2100 INIT_LIST_HEAD(&c->frdi_idx_list); 2101 INIT_LIST_HEAD(&c->unclean_leb_list); 2102 INIT_LIST_HEAD(&c->old_buds); 2103 INIT_LIST_HEAD(&c->orph_list); 2104 INIT_LIST_HEAD(&c->orph_new); 2105 c->no_chk_data_crc = 1; 2106 c->assert_action = ASSACT_RO; 2107 2108 c->highest_inum = UBIFS_FIRST_INO; 2109 c->lhead_lnum = c->ltail_lnum = UBIFS_LOG_LNUM; 2110 2111 ubi_get_volume_info(ubi, &c->vi); 2112 ubi_get_device_info(c->vi.ubi_num, &c->di); 2113 } 2114 return c; 2115 } 2116 2117 static int ubifs_fill_super(struct super_block *sb, void *data, int silent) 2118 { 2119 struct ubifs_info *c = sb->s_fs_info; 2120 struct inode *root; 2121 int err; 2122 2123 c->vfs_sb = sb; 2124 /* Re-open the UBI device in read-write mode */ 2125 c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READWRITE); 2126 if (IS_ERR(c->ubi)) { 2127 err = PTR_ERR(c->ubi); 2128 goto out; 2129 } 2130 2131 err = ubifs_parse_options(c, data, 0); 2132 if (err) 2133 goto out_close; 2134 2135 /* 2136 * UBIFS provides 'backing_dev_info' in order to disable read-ahead. For 2137 * UBIFS, I/O is not deferred, it is done immediately in readpage, 2138 * which means the user would have to wait not just for their own I/O 2139 * but the read-ahead I/O as well i.e. completely pointless. 2140 * 2141 * Read-ahead will be disabled because @sb->s_bdi->ra_pages is 0. Also 2142 * @sb->s_bdi->capabilities are initialized to 0 so there won't be any 2143 * writeback happening. 2144 */ 2145 err = super_setup_bdi_name(sb, "ubifs_%d_%d", c->vi.ubi_num, 2146 c->vi.vol_id); 2147 if (err) 2148 goto out_close; 2149 2150 sb->s_fs_info = c; 2151 sb->s_magic = UBIFS_SUPER_MAGIC; 2152 sb->s_blocksize = UBIFS_BLOCK_SIZE; 2153 sb->s_blocksize_bits = UBIFS_BLOCK_SHIFT; 2154 sb->s_maxbytes = c->max_inode_sz = key_max_inode_size(c); 2155 if (c->max_inode_sz > MAX_LFS_FILESIZE) 2156 sb->s_maxbytes = c->max_inode_sz = MAX_LFS_FILESIZE; 2157 sb->s_op = &ubifs_super_operations; 2158 #ifdef CONFIG_UBIFS_FS_XATTR 2159 sb->s_xattr = ubifs_xattr_handlers; 2160 #endif 2161 fscrypt_set_ops(sb, &ubifs_crypt_operations); 2162 2163 mutex_lock(&c->umount_mutex); 2164 err = mount_ubifs(c); 2165 if (err) { 2166 ubifs_assert(c, err < 0); 2167 goto out_unlock; 2168 } 2169 2170 /* Read the root inode */ 2171 root = ubifs_iget(sb, UBIFS_ROOT_INO); 2172 if (IS_ERR(root)) { 2173 err = PTR_ERR(root); 2174 goto out_umount; 2175 } 2176 2177 sb->s_root = d_make_root(root); 2178 if (!sb->s_root) { 2179 err = -ENOMEM; 2180 goto out_umount; 2181 } 2182 2183 mutex_unlock(&c->umount_mutex); 2184 return 0; 2185 2186 out_umount: 2187 ubifs_umount(c); 2188 out_unlock: 2189 mutex_unlock(&c->umount_mutex); 2190 out_close: 2191 ubi_close_volume(c->ubi); 2192 out: 2193 return err; 2194 } 2195 2196 static int sb_test(struct super_block *sb, void *data) 2197 { 2198 struct ubifs_info *c1 = data; 2199 struct ubifs_info *c = sb->s_fs_info; 2200 2201 return c->vi.cdev == c1->vi.cdev; 2202 } 2203 2204 static int sb_set(struct super_block *sb, void *data) 2205 { 2206 sb->s_fs_info = data; 2207 return set_anon_super(sb, NULL); 2208 } 2209 2210 static struct dentry *ubifs_mount(struct file_system_type *fs_type, int flags, 2211 const char *name, void *data) 2212 { 2213 struct ubi_volume_desc *ubi; 2214 struct ubifs_info *c; 2215 struct super_block *sb; 2216 int err; 2217 2218 dbg_gen("name %s, flags %#x", name, flags); 2219 2220 /* 2221 * Get UBI device number and volume ID. Mount it read-only so far 2222 * because this might be a new mount point, and UBI allows only one 2223 * read-write user at a time. 2224 */ 2225 ubi = open_ubi(name, UBI_READONLY); 2226 if (IS_ERR(ubi)) { 2227 if (!(flags & SB_SILENT)) 2228 pr_err("UBIFS error (pid: %d): cannot open \"%s\", error %d", 2229 current->pid, name, (int)PTR_ERR(ubi)); 2230 return ERR_CAST(ubi); 2231 } 2232 2233 c = alloc_ubifs_info(ubi); 2234 if (!c) { 2235 err = -ENOMEM; 2236 goto out_close; 2237 } 2238 2239 dbg_gen("opened ubi%d_%d", c->vi.ubi_num, c->vi.vol_id); 2240 2241 sb = sget(fs_type, sb_test, sb_set, flags, c); 2242 if (IS_ERR(sb)) { 2243 err = PTR_ERR(sb); 2244 kfree(c); 2245 goto out_close; 2246 } 2247 2248 if (sb->s_root) { 2249 struct ubifs_info *c1 = sb->s_fs_info; 2250 kfree(c); 2251 /* A new mount point for already mounted UBIFS */ 2252 dbg_gen("this ubi volume is already mounted"); 2253 if (!!(flags & SB_RDONLY) != c1->ro_mount) { 2254 err = -EBUSY; 2255 goto out_deact; 2256 } 2257 } else { 2258 err = ubifs_fill_super(sb, data, flags & SB_SILENT ? 1 : 0); 2259 if (err) 2260 goto out_deact; 2261 /* We do not support atime */ 2262 sb->s_flags |= SB_ACTIVE; 2263 if (IS_ENABLED(CONFIG_UBIFS_ATIME_SUPPORT)) 2264 ubifs_msg(c, "full atime support is enabled."); 2265 else 2266 sb->s_flags |= SB_NOATIME; 2267 } 2268 2269 /* 'fill_super()' opens ubi again so we must close it here */ 2270 ubi_close_volume(ubi); 2271 2272 return dget(sb->s_root); 2273 2274 out_deact: 2275 deactivate_locked_super(sb); 2276 out_close: 2277 ubi_close_volume(ubi); 2278 return ERR_PTR(err); 2279 } 2280 2281 static void kill_ubifs_super(struct super_block *s) 2282 { 2283 struct ubifs_info *c = s->s_fs_info; 2284 kill_anon_super(s); 2285 kfree(c); 2286 } 2287 2288 static struct file_system_type ubifs_fs_type = { 2289 .name = "ubifs", 2290 .owner = THIS_MODULE, 2291 .mount = ubifs_mount, 2292 .kill_sb = kill_ubifs_super, 2293 }; 2294 MODULE_ALIAS_FS("ubifs"); 2295 2296 /* 2297 * Inode slab cache constructor. 2298 */ 2299 static void inode_slab_ctor(void *obj) 2300 { 2301 struct ubifs_inode *ui = obj; 2302 inode_init_once(&ui->vfs_inode); 2303 } 2304 2305 static int __init ubifs_init(void) 2306 { 2307 int err; 2308 2309 BUILD_BUG_ON(sizeof(struct ubifs_ch) != 24); 2310 2311 /* Make sure node sizes are 8-byte aligned */ 2312 BUILD_BUG_ON(UBIFS_CH_SZ & 7); 2313 BUILD_BUG_ON(UBIFS_INO_NODE_SZ & 7); 2314 BUILD_BUG_ON(UBIFS_DENT_NODE_SZ & 7); 2315 BUILD_BUG_ON(UBIFS_XENT_NODE_SZ & 7); 2316 BUILD_BUG_ON(UBIFS_DATA_NODE_SZ & 7); 2317 BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ & 7); 2318 BUILD_BUG_ON(UBIFS_SB_NODE_SZ & 7); 2319 BUILD_BUG_ON(UBIFS_MST_NODE_SZ & 7); 2320 BUILD_BUG_ON(UBIFS_REF_NODE_SZ & 7); 2321 BUILD_BUG_ON(UBIFS_CS_NODE_SZ & 7); 2322 BUILD_BUG_ON(UBIFS_ORPH_NODE_SZ & 7); 2323 2324 BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ & 7); 2325 BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ & 7); 2326 BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ & 7); 2327 BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ & 7); 2328 BUILD_BUG_ON(UBIFS_MAX_NODE_SZ & 7); 2329 BUILD_BUG_ON(MIN_WRITE_SZ & 7); 2330 2331 /* Check min. node size */ 2332 BUILD_BUG_ON(UBIFS_INO_NODE_SZ < MIN_WRITE_SZ); 2333 BUILD_BUG_ON(UBIFS_DENT_NODE_SZ < MIN_WRITE_SZ); 2334 BUILD_BUG_ON(UBIFS_XENT_NODE_SZ < MIN_WRITE_SZ); 2335 BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ < MIN_WRITE_SZ); 2336 2337 BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ > UBIFS_MAX_NODE_SZ); 2338 BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ > UBIFS_MAX_NODE_SZ); 2339 BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ > UBIFS_MAX_NODE_SZ); 2340 BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ > UBIFS_MAX_NODE_SZ); 2341 2342 /* Defined node sizes */ 2343 BUILD_BUG_ON(UBIFS_SB_NODE_SZ != 4096); 2344 BUILD_BUG_ON(UBIFS_MST_NODE_SZ != 512); 2345 BUILD_BUG_ON(UBIFS_INO_NODE_SZ != 160); 2346 BUILD_BUG_ON(UBIFS_REF_NODE_SZ != 64); 2347 2348 /* 2349 * We use 2 bit wide bit-fields to store compression type, which should 2350 * be amended if more compressors are added. The bit-fields are: 2351 * @compr_type in 'struct ubifs_inode', @default_compr in 2352 * 'struct ubifs_info' and @compr_type in 'struct ubifs_mount_opts'. 2353 */ 2354 BUILD_BUG_ON(UBIFS_COMPR_TYPES_CNT > 4); 2355 2356 /* 2357 * We require that PAGE_SIZE is greater-than-or-equal-to 2358 * UBIFS_BLOCK_SIZE. It is assumed that both are powers of 2. 2359 */ 2360 if (PAGE_SIZE < UBIFS_BLOCK_SIZE) { 2361 pr_err("UBIFS error (pid %d): VFS page cache size is %u bytes, but UBIFS requires at least 4096 bytes", 2362 current->pid, (unsigned int)PAGE_SIZE); 2363 return -EINVAL; 2364 } 2365 2366 ubifs_inode_slab = kmem_cache_create("ubifs_inode_slab", 2367 sizeof(struct ubifs_inode), 0, 2368 SLAB_MEM_SPREAD | SLAB_RECLAIM_ACCOUNT | 2369 SLAB_ACCOUNT, &inode_slab_ctor); 2370 if (!ubifs_inode_slab) 2371 return -ENOMEM; 2372 2373 err = register_shrinker(&ubifs_shrinker_info); 2374 if (err) 2375 goto out_slab; 2376 2377 err = ubifs_compressors_init(); 2378 if (err) 2379 goto out_shrinker; 2380 2381 dbg_debugfs_init(); 2382 2383 err = register_filesystem(&ubifs_fs_type); 2384 if (err) { 2385 pr_err("UBIFS error (pid %d): cannot register file system, error %d", 2386 current->pid, err); 2387 goto out_dbg; 2388 } 2389 return 0; 2390 2391 out_dbg: 2392 dbg_debugfs_exit(); 2393 ubifs_compressors_exit(); 2394 out_shrinker: 2395 unregister_shrinker(&ubifs_shrinker_info); 2396 out_slab: 2397 kmem_cache_destroy(ubifs_inode_slab); 2398 return err; 2399 } 2400 /* late_initcall to let compressors initialize first */ 2401 late_initcall(ubifs_init); 2402 2403 static void __exit ubifs_exit(void) 2404 { 2405 WARN_ON(!list_empty(&ubifs_infos)); 2406 WARN_ON(atomic_long_read(&ubifs_clean_zn_cnt) != 0); 2407 2408 dbg_debugfs_exit(); 2409 ubifs_compressors_exit(); 2410 unregister_shrinker(&ubifs_shrinker_info); 2411 2412 /* 2413 * Make sure all delayed rcu free inodes are flushed before we 2414 * destroy cache. 2415 */ 2416 rcu_barrier(); 2417 kmem_cache_destroy(ubifs_inode_slab); 2418 unregister_filesystem(&ubifs_fs_type); 2419 } 2420 module_exit(ubifs_exit); 2421 2422 MODULE_LICENSE("GPL"); 2423 MODULE_VERSION(__stringify(UBIFS_VERSION)); 2424 MODULE_AUTHOR("Artem Bityutskiy, Adrian Hunter"); 2425 MODULE_DESCRIPTION("UBIFS - UBI File System"); 2426