1 /* 2 * This file is part of UBIFS. 3 * 4 * Copyright (C) 2006-2008 Nokia Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 as published by 8 * the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 13 * more details. 14 * 15 * You should have received a copy of the GNU General Public License along with 16 * this program; if not, write to the Free Software Foundation, Inc., 51 17 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 18 * 19 * Authors: Artem Bityutskiy (Битюцкий Артём) 20 * Adrian Hunter 21 */ 22 23 /* 24 * This file implements UBIFS initialization and VFS superblock operations. Some 25 * initialization stuff which is rather large and complex is placed at 26 * corresponding subsystems, but most of it is here. 27 */ 28 29 #include <linux/init.h> 30 #include <linux/slab.h> 31 #include <linux/module.h> 32 #include <linux/ctype.h> 33 #include <linux/kthread.h> 34 #include <linux/parser.h> 35 #include <linux/seq_file.h> 36 #include <linux/mount.h> 37 #include <linux/math64.h> 38 #include <linux/writeback.h> 39 #include <linux/smp_lock.h> 40 #include "ubifs.h" 41 42 /* 43 * Maximum amount of memory we may 'kmalloc()' without worrying that we are 44 * allocating too much. 45 */ 46 #define UBIFS_KMALLOC_OK (128*1024) 47 48 /* Slab cache for UBIFS inodes */ 49 struct kmem_cache *ubifs_inode_slab; 50 51 /* UBIFS TNC shrinker description */ 52 static struct shrinker ubifs_shrinker_info = { 53 .shrink = ubifs_shrinker, 54 .seeks = DEFAULT_SEEKS, 55 }; 56 57 /** 58 * validate_inode - validate inode. 59 * @c: UBIFS file-system description object 60 * @inode: the inode to validate 61 * 62 * This is a helper function for 'ubifs_iget()' which validates various fields 63 * of a newly built inode to make sure they contain sane values and prevent 64 * possible vulnerabilities. Returns zero if the inode is all right and 65 * a non-zero error code if not. 66 */ 67 static int validate_inode(struct ubifs_info *c, const struct inode *inode) 68 { 69 int err; 70 const struct ubifs_inode *ui = ubifs_inode(inode); 71 72 if (inode->i_size > c->max_inode_sz) { 73 ubifs_err("inode is too large (%lld)", 74 (long long)inode->i_size); 75 return 1; 76 } 77 78 if (ui->compr_type < 0 || ui->compr_type >= UBIFS_COMPR_TYPES_CNT) { 79 ubifs_err("unknown compression type %d", ui->compr_type); 80 return 2; 81 } 82 83 if (ui->xattr_names + ui->xattr_cnt > XATTR_LIST_MAX) 84 return 3; 85 86 if (ui->data_len < 0 || ui->data_len > UBIFS_MAX_INO_DATA) 87 return 4; 88 89 if (ui->xattr && (inode->i_mode & S_IFMT) != S_IFREG) 90 return 5; 91 92 if (!ubifs_compr_present(ui->compr_type)) { 93 ubifs_warn("inode %lu uses '%s' compression, but it was not " 94 "compiled in", inode->i_ino, 95 ubifs_compr_name(ui->compr_type)); 96 } 97 98 err = dbg_check_dir_size(c, inode); 99 return err; 100 } 101 102 struct inode *ubifs_iget(struct super_block *sb, unsigned long inum) 103 { 104 int err; 105 union ubifs_key key; 106 struct ubifs_ino_node *ino; 107 struct ubifs_info *c = sb->s_fs_info; 108 struct inode *inode; 109 struct ubifs_inode *ui; 110 111 dbg_gen("inode %lu", inum); 112 113 inode = iget_locked(sb, inum); 114 if (!inode) 115 return ERR_PTR(-ENOMEM); 116 if (!(inode->i_state & I_NEW)) 117 return inode; 118 ui = ubifs_inode(inode); 119 120 ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS); 121 if (!ino) { 122 err = -ENOMEM; 123 goto out; 124 } 125 126 ino_key_init(c, &key, inode->i_ino); 127 128 err = ubifs_tnc_lookup(c, &key, ino); 129 if (err) 130 goto out_ino; 131 132 inode->i_flags |= (S_NOCMTIME | S_NOATIME); 133 inode->i_nlink = le32_to_cpu(ino->nlink); 134 inode->i_uid = le32_to_cpu(ino->uid); 135 inode->i_gid = le32_to_cpu(ino->gid); 136 inode->i_atime.tv_sec = (int64_t)le64_to_cpu(ino->atime_sec); 137 inode->i_atime.tv_nsec = le32_to_cpu(ino->atime_nsec); 138 inode->i_mtime.tv_sec = (int64_t)le64_to_cpu(ino->mtime_sec); 139 inode->i_mtime.tv_nsec = le32_to_cpu(ino->mtime_nsec); 140 inode->i_ctime.tv_sec = (int64_t)le64_to_cpu(ino->ctime_sec); 141 inode->i_ctime.tv_nsec = le32_to_cpu(ino->ctime_nsec); 142 inode->i_mode = le32_to_cpu(ino->mode); 143 inode->i_size = le64_to_cpu(ino->size); 144 145 ui->data_len = le32_to_cpu(ino->data_len); 146 ui->flags = le32_to_cpu(ino->flags); 147 ui->compr_type = le16_to_cpu(ino->compr_type); 148 ui->creat_sqnum = le64_to_cpu(ino->creat_sqnum); 149 ui->xattr_cnt = le32_to_cpu(ino->xattr_cnt); 150 ui->xattr_size = le32_to_cpu(ino->xattr_size); 151 ui->xattr_names = le32_to_cpu(ino->xattr_names); 152 ui->synced_i_size = ui->ui_size = inode->i_size; 153 154 ui->xattr = (ui->flags & UBIFS_XATTR_FL) ? 1 : 0; 155 156 err = validate_inode(c, inode); 157 if (err) 158 goto out_invalid; 159 160 /* Disable read-ahead */ 161 inode->i_mapping->backing_dev_info = &c->bdi; 162 163 switch (inode->i_mode & S_IFMT) { 164 case S_IFREG: 165 inode->i_mapping->a_ops = &ubifs_file_address_operations; 166 inode->i_op = &ubifs_file_inode_operations; 167 inode->i_fop = &ubifs_file_operations; 168 if (ui->xattr) { 169 ui->data = kmalloc(ui->data_len + 1, GFP_NOFS); 170 if (!ui->data) { 171 err = -ENOMEM; 172 goto out_ino; 173 } 174 memcpy(ui->data, ino->data, ui->data_len); 175 ((char *)ui->data)[ui->data_len] = '\0'; 176 } else if (ui->data_len != 0) { 177 err = 10; 178 goto out_invalid; 179 } 180 break; 181 case S_IFDIR: 182 inode->i_op = &ubifs_dir_inode_operations; 183 inode->i_fop = &ubifs_dir_operations; 184 if (ui->data_len != 0) { 185 err = 11; 186 goto out_invalid; 187 } 188 break; 189 case S_IFLNK: 190 inode->i_op = &ubifs_symlink_inode_operations; 191 if (ui->data_len <= 0 || ui->data_len > UBIFS_MAX_INO_DATA) { 192 err = 12; 193 goto out_invalid; 194 } 195 ui->data = kmalloc(ui->data_len + 1, GFP_NOFS); 196 if (!ui->data) { 197 err = -ENOMEM; 198 goto out_ino; 199 } 200 memcpy(ui->data, ino->data, ui->data_len); 201 ((char *)ui->data)[ui->data_len] = '\0'; 202 break; 203 case S_IFBLK: 204 case S_IFCHR: 205 { 206 dev_t rdev; 207 union ubifs_dev_desc *dev; 208 209 ui->data = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS); 210 if (!ui->data) { 211 err = -ENOMEM; 212 goto out_ino; 213 } 214 215 dev = (union ubifs_dev_desc *)ino->data; 216 if (ui->data_len == sizeof(dev->new)) 217 rdev = new_decode_dev(le32_to_cpu(dev->new)); 218 else if (ui->data_len == sizeof(dev->huge)) 219 rdev = huge_decode_dev(le64_to_cpu(dev->huge)); 220 else { 221 err = 13; 222 goto out_invalid; 223 } 224 memcpy(ui->data, ino->data, ui->data_len); 225 inode->i_op = &ubifs_file_inode_operations; 226 init_special_inode(inode, inode->i_mode, rdev); 227 break; 228 } 229 case S_IFSOCK: 230 case S_IFIFO: 231 inode->i_op = &ubifs_file_inode_operations; 232 init_special_inode(inode, inode->i_mode, 0); 233 if (ui->data_len != 0) { 234 err = 14; 235 goto out_invalid; 236 } 237 break; 238 default: 239 err = 15; 240 goto out_invalid; 241 } 242 243 kfree(ino); 244 ubifs_set_inode_flags(inode); 245 unlock_new_inode(inode); 246 return inode; 247 248 out_invalid: 249 ubifs_err("inode %lu validation failed, error %d", inode->i_ino, err); 250 dbg_dump_node(c, ino); 251 dbg_dump_inode(c, inode); 252 err = -EINVAL; 253 out_ino: 254 kfree(ino); 255 out: 256 ubifs_err("failed to read inode %lu, error %d", inode->i_ino, err); 257 iget_failed(inode); 258 return ERR_PTR(err); 259 } 260 261 static struct inode *ubifs_alloc_inode(struct super_block *sb) 262 { 263 struct ubifs_inode *ui; 264 265 ui = kmem_cache_alloc(ubifs_inode_slab, GFP_NOFS); 266 if (!ui) 267 return NULL; 268 269 memset((void *)ui + sizeof(struct inode), 0, 270 sizeof(struct ubifs_inode) - sizeof(struct inode)); 271 mutex_init(&ui->ui_mutex); 272 spin_lock_init(&ui->ui_lock); 273 return &ui->vfs_inode; 274 }; 275 276 static void ubifs_destroy_inode(struct inode *inode) 277 { 278 struct ubifs_inode *ui = ubifs_inode(inode); 279 280 kfree(ui->data); 281 kmem_cache_free(ubifs_inode_slab, inode); 282 } 283 284 /* 285 * Note, Linux write-back code calls this without 'i_mutex'. 286 */ 287 static int ubifs_write_inode(struct inode *inode, int wait) 288 { 289 int err = 0; 290 struct ubifs_info *c = inode->i_sb->s_fs_info; 291 struct ubifs_inode *ui = ubifs_inode(inode); 292 293 ubifs_assert(!ui->xattr); 294 if (is_bad_inode(inode)) 295 return 0; 296 297 mutex_lock(&ui->ui_mutex); 298 /* 299 * Due to races between write-back forced by budgeting 300 * (see 'sync_some_inodes()') and pdflush write-back, the inode may 301 * have already been synchronized, do not do this again. This might 302 * also happen if it was synchronized in an VFS operation, e.g. 303 * 'ubifs_link()'. 304 */ 305 if (!ui->dirty) { 306 mutex_unlock(&ui->ui_mutex); 307 return 0; 308 } 309 310 /* 311 * As an optimization, do not write orphan inodes to the media just 312 * because this is not needed. 313 */ 314 dbg_gen("inode %lu, mode %#x, nlink %u", 315 inode->i_ino, (int)inode->i_mode, inode->i_nlink); 316 if (inode->i_nlink) { 317 err = ubifs_jnl_write_inode(c, inode); 318 if (err) 319 ubifs_err("can't write inode %lu, error %d", 320 inode->i_ino, err); 321 } 322 323 ui->dirty = 0; 324 mutex_unlock(&ui->ui_mutex); 325 ubifs_release_dirty_inode_budget(c, ui); 326 return err; 327 } 328 329 static void ubifs_delete_inode(struct inode *inode) 330 { 331 int err; 332 struct ubifs_info *c = inode->i_sb->s_fs_info; 333 struct ubifs_inode *ui = ubifs_inode(inode); 334 335 if (ui->xattr) 336 /* 337 * Extended attribute inode deletions are fully handled in 338 * 'ubifs_removexattr()'. These inodes are special and have 339 * limited usage, so there is nothing to do here. 340 */ 341 goto out; 342 343 dbg_gen("inode %lu, mode %#x", inode->i_ino, (int)inode->i_mode); 344 ubifs_assert(!atomic_read(&inode->i_count)); 345 ubifs_assert(inode->i_nlink == 0); 346 347 truncate_inode_pages(&inode->i_data, 0); 348 if (is_bad_inode(inode)) 349 goto out; 350 351 ui->ui_size = inode->i_size = 0; 352 err = ubifs_jnl_delete_inode(c, inode); 353 if (err) 354 /* 355 * Worst case we have a lost orphan inode wasting space, so a 356 * simple error message is OK here. 357 */ 358 ubifs_err("can't delete inode %lu, error %d", 359 inode->i_ino, err); 360 361 out: 362 if (ui->dirty) 363 ubifs_release_dirty_inode_budget(c, ui); 364 else { 365 /* We've deleted something - clean the "no space" flags */ 366 c->nospace = c->nospace_rp = 0; 367 smp_wmb(); 368 } 369 clear_inode(inode); 370 } 371 372 static void ubifs_dirty_inode(struct inode *inode) 373 { 374 struct ubifs_inode *ui = ubifs_inode(inode); 375 376 ubifs_assert(mutex_is_locked(&ui->ui_mutex)); 377 if (!ui->dirty) { 378 ui->dirty = 1; 379 dbg_gen("inode %lu", inode->i_ino); 380 } 381 } 382 383 static int ubifs_statfs(struct dentry *dentry, struct kstatfs *buf) 384 { 385 struct ubifs_info *c = dentry->d_sb->s_fs_info; 386 unsigned long long free; 387 __le32 *uuid = (__le32 *)c->uuid; 388 389 free = ubifs_get_free_space(c); 390 dbg_gen("free space %lld bytes (%lld blocks)", 391 free, free >> UBIFS_BLOCK_SHIFT); 392 393 buf->f_type = UBIFS_SUPER_MAGIC; 394 buf->f_bsize = UBIFS_BLOCK_SIZE; 395 buf->f_blocks = c->block_cnt; 396 buf->f_bfree = free >> UBIFS_BLOCK_SHIFT; 397 if (free > c->report_rp_size) 398 buf->f_bavail = (free - c->report_rp_size) >> UBIFS_BLOCK_SHIFT; 399 else 400 buf->f_bavail = 0; 401 buf->f_files = 0; 402 buf->f_ffree = 0; 403 buf->f_namelen = UBIFS_MAX_NLEN; 404 buf->f_fsid.val[0] = le32_to_cpu(uuid[0]) ^ le32_to_cpu(uuid[2]); 405 buf->f_fsid.val[1] = le32_to_cpu(uuid[1]) ^ le32_to_cpu(uuid[3]); 406 ubifs_assert(buf->f_bfree <= c->block_cnt); 407 return 0; 408 } 409 410 static int ubifs_show_options(struct seq_file *s, struct vfsmount *mnt) 411 { 412 struct ubifs_info *c = mnt->mnt_sb->s_fs_info; 413 414 if (c->mount_opts.unmount_mode == 2) 415 seq_printf(s, ",fast_unmount"); 416 else if (c->mount_opts.unmount_mode == 1) 417 seq_printf(s, ",norm_unmount"); 418 419 if (c->mount_opts.bulk_read == 2) 420 seq_printf(s, ",bulk_read"); 421 else if (c->mount_opts.bulk_read == 1) 422 seq_printf(s, ",no_bulk_read"); 423 424 if (c->mount_opts.chk_data_crc == 2) 425 seq_printf(s, ",chk_data_crc"); 426 else if (c->mount_opts.chk_data_crc == 1) 427 seq_printf(s, ",no_chk_data_crc"); 428 429 if (c->mount_opts.override_compr) { 430 seq_printf(s, ",compr=%s", 431 ubifs_compr_name(c->mount_opts.compr_type)); 432 } 433 434 return 0; 435 } 436 437 static int ubifs_sync_fs(struct super_block *sb, int wait) 438 { 439 int i, err; 440 struct ubifs_info *c = sb->s_fs_info; 441 442 /* 443 * Zero @wait is just an advisory thing to help the file system shove 444 * lots of data into the queues, and there will be the second 445 * '->sync_fs()' call, with non-zero @wait. 446 */ 447 if (!wait) 448 return 0; 449 450 /* 451 * VFS calls '->sync_fs()' before synchronizing all dirty inodes and 452 * pages, so synchronize them first, then commit the journal. Strictly 453 * speaking, it is not necessary to commit the journal here, 454 * synchronizing write-buffers would be enough. But committing makes 455 * UBIFS free space predictions much more accurate, so we want to let 456 * the user be able to get more accurate results of 'statfs()' after 457 * they synchronize the file system. 458 */ 459 sync_inodes_sb(sb); 460 461 /* 462 * Synchronize write buffers, because 'ubifs_run_commit()' does not 463 * do this if it waits for an already running commit. 464 */ 465 for (i = 0; i < c->jhead_cnt; i++) { 466 err = ubifs_wbuf_sync(&c->jheads[i].wbuf); 467 if (err) 468 return err; 469 } 470 471 err = ubifs_run_commit(c); 472 if (err) 473 return err; 474 475 return ubi_sync(c->vi.ubi_num); 476 } 477 478 /** 479 * init_constants_early - initialize UBIFS constants. 480 * @c: UBIFS file-system description object 481 * 482 * This function initialize UBIFS constants which do not need the superblock to 483 * be read. It also checks that the UBI volume satisfies basic UBIFS 484 * requirements. Returns zero in case of success and a negative error code in 485 * case of failure. 486 */ 487 static int init_constants_early(struct ubifs_info *c) 488 { 489 if (c->vi.corrupted) { 490 ubifs_warn("UBI volume is corrupted - read-only mode"); 491 c->ro_media = 1; 492 } 493 494 if (c->di.ro_mode) { 495 ubifs_msg("read-only UBI device"); 496 c->ro_media = 1; 497 } 498 499 if (c->vi.vol_type == UBI_STATIC_VOLUME) { 500 ubifs_msg("static UBI volume - read-only mode"); 501 c->ro_media = 1; 502 } 503 504 c->leb_cnt = c->vi.size; 505 c->leb_size = c->vi.usable_leb_size; 506 c->half_leb_size = c->leb_size / 2; 507 c->min_io_size = c->di.min_io_size; 508 c->min_io_shift = fls(c->min_io_size) - 1; 509 510 if (c->leb_size < UBIFS_MIN_LEB_SZ) { 511 ubifs_err("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_err("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_err("bad min. I/O size %d", c->min_io_size); 524 return -EINVAL; 525 } 526 527 /* 528 * UBIFS aligns all node to 8-byte boundary, so to make function in 529 * io.c simpler, assume minimum I/O unit size to be 8 bytes if it is 530 * less than 8. 531 */ 532 if (c->min_io_size < 8) { 533 c->min_io_size = 8; 534 c->min_io_shift = 3; 535 } 536 537 c->ref_node_alsz = ALIGN(UBIFS_REF_NODE_SZ, c->min_io_size); 538 c->mst_node_alsz = ALIGN(UBIFS_MST_NODE_SZ, c->min_io_size); 539 540 /* 541 * Initialize node length ranges which are mostly needed for node 542 * length validation. 543 */ 544 c->ranges[UBIFS_PAD_NODE].len = UBIFS_PAD_NODE_SZ; 545 c->ranges[UBIFS_SB_NODE].len = UBIFS_SB_NODE_SZ; 546 c->ranges[UBIFS_MST_NODE].len = UBIFS_MST_NODE_SZ; 547 c->ranges[UBIFS_REF_NODE].len = UBIFS_REF_NODE_SZ; 548 c->ranges[UBIFS_TRUN_NODE].len = UBIFS_TRUN_NODE_SZ; 549 c->ranges[UBIFS_CS_NODE].len = UBIFS_CS_NODE_SZ; 550 551 c->ranges[UBIFS_INO_NODE].min_len = UBIFS_INO_NODE_SZ; 552 c->ranges[UBIFS_INO_NODE].max_len = UBIFS_MAX_INO_NODE_SZ; 553 c->ranges[UBIFS_ORPH_NODE].min_len = 554 UBIFS_ORPH_NODE_SZ + sizeof(__le64); 555 c->ranges[UBIFS_ORPH_NODE].max_len = c->leb_size; 556 c->ranges[UBIFS_DENT_NODE].min_len = UBIFS_DENT_NODE_SZ; 557 c->ranges[UBIFS_DENT_NODE].max_len = UBIFS_MAX_DENT_NODE_SZ; 558 c->ranges[UBIFS_XENT_NODE].min_len = UBIFS_XENT_NODE_SZ; 559 c->ranges[UBIFS_XENT_NODE].max_len = UBIFS_MAX_XENT_NODE_SZ; 560 c->ranges[UBIFS_DATA_NODE].min_len = UBIFS_DATA_NODE_SZ; 561 c->ranges[UBIFS_DATA_NODE].max_len = UBIFS_MAX_DATA_NODE_SZ; 562 /* 563 * Minimum indexing node size is amended later when superblock is 564 * read and the key length is known. 565 */ 566 c->ranges[UBIFS_IDX_NODE].min_len = UBIFS_IDX_NODE_SZ + UBIFS_BRANCH_SZ; 567 /* 568 * Maximum indexing node size is amended later when superblock is 569 * read and the fanout is known. 570 */ 571 c->ranges[UBIFS_IDX_NODE].max_len = INT_MAX; 572 573 /* 574 * Initialize dead and dark LEB space watermarks. See gc.c for comments 575 * about these values. 576 */ 577 c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size); 578 c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size); 579 580 /* 581 * Calculate how many bytes would be wasted at the end of LEB if it was 582 * fully filled with data nodes of maximum size. This is used in 583 * calculations when reporting free space. 584 */ 585 c->leb_overhead = c->leb_size % UBIFS_MAX_DATA_NODE_SZ; 586 587 /* Buffer size for bulk-reads */ 588 c->max_bu_buf_len = UBIFS_MAX_BULK_READ * UBIFS_MAX_DATA_NODE_SZ; 589 if (c->max_bu_buf_len > c->leb_size) 590 c->max_bu_buf_len = c->leb_size; 591 return 0; 592 } 593 594 /** 595 * bud_wbuf_callback - bud LEB write-buffer synchronization call-back. 596 * @c: UBIFS file-system description object 597 * @lnum: LEB the write-buffer was synchronized to 598 * @free: how many free bytes left in this LEB 599 * @pad: how many bytes were padded 600 * 601 * This is a callback function which is called by the I/O unit when the 602 * write-buffer is synchronized. We need this to correctly maintain space 603 * accounting in bud logical eraseblocks. This function returns zero in case of 604 * success and a negative error code in case of failure. 605 * 606 * This function actually belongs to the journal, but we keep it here because 607 * we want to keep it static. 608 */ 609 static int bud_wbuf_callback(struct ubifs_info *c, int lnum, int free, int pad) 610 { 611 return ubifs_update_one_lp(c, lnum, free, pad, 0, 0); 612 } 613 614 /* 615 * init_constants_sb - initialize UBIFS constants. 616 * @c: UBIFS file-system description object 617 * 618 * This is a helper function which initializes various UBIFS constants after 619 * the superblock has been read. It also checks various UBIFS parameters and 620 * makes sure they are all right. Returns zero in case of success and a 621 * negative error code in case of failure. 622 */ 623 static int init_constants_sb(struct ubifs_info *c) 624 { 625 int tmp, err; 626 long long tmp64; 627 628 c->main_bytes = (long long)c->main_lebs * c->leb_size; 629 c->max_znode_sz = sizeof(struct ubifs_znode) + 630 c->fanout * sizeof(struct ubifs_zbranch); 631 632 tmp = ubifs_idx_node_sz(c, 1); 633 c->ranges[UBIFS_IDX_NODE].min_len = tmp; 634 c->min_idx_node_sz = ALIGN(tmp, 8); 635 636 tmp = ubifs_idx_node_sz(c, c->fanout); 637 c->ranges[UBIFS_IDX_NODE].max_len = tmp; 638 c->max_idx_node_sz = ALIGN(tmp, 8); 639 640 /* Make sure LEB size is large enough to fit full commit */ 641 tmp = UBIFS_CS_NODE_SZ + UBIFS_REF_NODE_SZ * c->jhead_cnt; 642 tmp = ALIGN(tmp, c->min_io_size); 643 if (tmp > c->leb_size) { 644 dbg_err("too small LEB size %d, at least %d needed", 645 c->leb_size, tmp); 646 return -EINVAL; 647 } 648 649 /* 650 * Make sure that the log is large enough to fit reference nodes for 651 * all buds plus one reserved LEB. 652 */ 653 tmp64 = c->max_bud_bytes + c->leb_size - 1; 654 c->max_bud_cnt = div_u64(tmp64, c->leb_size); 655 tmp = (c->ref_node_alsz * c->max_bud_cnt + c->leb_size - 1); 656 tmp /= c->leb_size; 657 tmp += 1; 658 if (c->log_lebs < tmp) { 659 dbg_err("too small log %d LEBs, required min. %d LEBs", 660 c->log_lebs, tmp); 661 return -EINVAL; 662 } 663 664 /* 665 * When budgeting we assume worst-case scenarios when the pages are not 666 * be compressed and direntries are of the maximum size. 667 * 668 * Note, data, which may be stored in inodes is budgeted separately, so 669 * it is not included into 'c->inode_budget'. 670 */ 671 c->page_budget = UBIFS_MAX_DATA_NODE_SZ * UBIFS_BLOCKS_PER_PAGE; 672 c->inode_budget = UBIFS_INO_NODE_SZ; 673 c->dent_budget = UBIFS_MAX_DENT_NODE_SZ; 674 675 /* 676 * When the amount of flash space used by buds becomes 677 * 'c->max_bud_bytes', UBIFS just blocks all writers and starts commit. 678 * The writers are unblocked when the commit is finished. To avoid 679 * writers to be blocked UBIFS initiates background commit in advance, 680 * when number of bud bytes becomes above the limit defined below. 681 */ 682 c->bg_bud_bytes = (c->max_bud_bytes * 13) >> 4; 683 684 /* 685 * Ensure minimum journal size. All the bytes in the journal heads are 686 * considered to be used, when calculating the current journal usage. 687 * Consequently, if the journal is too small, UBIFS will treat it as 688 * always full. 689 */ 690 tmp64 = (long long)(c->jhead_cnt + 1) * c->leb_size + 1; 691 if (c->bg_bud_bytes < tmp64) 692 c->bg_bud_bytes = tmp64; 693 if (c->max_bud_bytes < tmp64 + c->leb_size) 694 c->max_bud_bytes = tmp64 + c->leb_size; 695 696 err = ubifs_calc_lpt_geom(c); 697 if (err) 698 return err; 699 700 /* Initialize effective LEB size used in budgeting calculations */ 701 c->idx_leb_size = c->leb_size - c->max_idx_node_sz; 702 return 0; 703 } 704 705 /* 706 * init_constants_master - initialize UBIFS constants. 707 * @c: UBIFS file-system description object 708 * 709 * This is a helper function which initializes various UBIFS constants after 710 * the master node has been read. It also checks various UBIFS parameters and 711 * makes sure they are all right. 712 */ 713 static void init_constants_master(struct ubifs_info *c) 714 { 715 long long tmp64; 716 717 c->min_idx_lebs = ubifs_calc_min_idx_lebs(c); 718 c->report_rp_size = ubifs_reported_space(c, c->rp_size); 719 720 /* 721 * Calculate total amount of FS blocks. This number is not used 722 * internally because it does not make much sense for UBIFS, but it is 723 * necessary to report something for the 'statfs()' call. 724 * 725 * Subtract the LEB reserved for GC, the LEB which is reserved for 726 * deletions, minimum LEBs for the index, and assume only one journal 727 * head is available. 728 */ 729 tmp64 = c->main_lebs - 1 - 1 - MIN_INDEX_LEBS - c->jhead_cnt + 1; 730 tmp64 *= (long long)c->leb_size - c->leb_overhead; 731 tmp64 = ubifs_reported_space(c, tmp64); 732 c->block_cnt = tmp64 >> UBIFS_BLOCK_SHIFT; 733 } 734 735 /** 736 * take_gc_lnum - reserve GC LEB. 737 * @c: UBIFS file-system description object 738 * 739 * This function ensures that the LEB reserved for garbage collection is marked 740 * as "taken" in lprops. We also have to set free space to LEB size and dirty 741 * space to zero, because lprops may contain out-of-date information if the 742 * file-system was un-mounted before it has been committed. This function 743 * returns zero in case of success and a negative error code in case of 744 * failure. 745 */ 746 static int take_gc_lnum(struct ubifs_info *c) 747 { 748 int err; 749 750 if (c->gc_lnum == -1) { 751 ubifs_err("no LEB for GC"); 752 return -EINVAL; 753 } 754 755 /* And we have to tell lprops that this LEB is taken */ 756 err = ubifs_change_one_lp(c, c->gc_lnum, c->leb_size, 0, 757 LPROPS_TAKEN, 0, 0); 758 return err; 759 } 760 761 /** 762 * alloc_wbufs - allocate write-buffers. 763 * @c: UBIFS file-system description object 764 * 765 * This helper function allocates and initializes UBIFS write-buffers. Returns 766 * zero in case of success and %-ENOMEM in case of failure. 767 */ 768 static int alloc_wbufs(struct ubifs_info *c) 769 { 770 int i, err; 771 772 c->jheads = kzalloc(c->jhead_cnt * sizeof(struct ubifs_jhead), 773 GFP_KERNEL); 774 if (!c->jheads) 775 return -ENOMEM; 776 777 /* Initialize journal heads */ 778 for (i = 0; i < c->jhead_cnt; i++) { 779 INIT_LIST_HEAD(&c->jheads[i].buds_list); 780 err = ubifs_wbuf_init(c, &c->jheads[i].wbuf); 781 if (err) 782 return err; 783 784 c->jheads[i].wbuf.sync_callback = &bud_wbuf_callback; 785 c->jheads[i].wbuf.jhead = i; 786 } 787 788 c->jheads[BASEHD].wbuf.dtype = UBI_SHORTTERM; 789 /* 790 * Garbage Collector head likely contains long-term data and 791 * does not need to be synchronized by timer. 792 */ 793 c->jheads[GCHD].wbuf.dtype = UBI_LONGTERM; 794 c->jheads[GCHD].wbuf.no_timer = 1; 795 796 return 0; 797 } 798 799 /** 800 * free_wbufs - free write-buffers. 801 * @c: UBIFS file-system description object 802 */ 803 static void free_wbufs(struct ubifs_info *c) 804 { 805 int i; 806 807 if (c->jheads) { 808 for (i = 0; i < c->jhead_cnt; i++) { 809 kfree(c->jheads[i].wbuf.buf); 810 kfree(c->jheads[i].wbuf.inodes); 811 } 812 kfree(c->jheads); 813 c->jheads = NULL; 814 } 815 } 816 817 /** 818 * free_orphans - free orphans. 819 * @c: UBIFS file-system description object 820 */ 821 static void free_orphans(struct ubifs_info *c) 822 { 823 struct ubifs_orphan *orph; 824 825 while (c->orph_dnext) { 826 orph = c->orph_dnext; 827 c->orph_dnext = orph->dnext; 828 list_del(&orph->list); 829 kfree(orph); 830 } 831 832 while (!list_empty(&c->orph_list)) { 833 orph = list_entry(c->orph_list.next, struct ubifs_orphan, list); 834 list_del(&orph->list); 835 kfree(orph); 836 dbg_err("orphan list not empty at unmount"); 837 } 838 839 vfree(c->orph_buf); 840 c->orph_buf = NULL; 841 } 842 843 /** 844 * free_buds - free per-bud objects. 845 * @c: UBIFS file-system description object 846 */ 847 static void free_buds(struct ubifs_info *c) 848 { 849 struct rb_node *this = c->buds.rb_node; 850 struct ubifs_bud *bud; 851 852 while (this) { 853 if (this->rb_left) 854 this = this->rb_left; 855 else if (this->rb_right) 856 this = this->rb_right; 857 else { 858 bud = rb_entry(this, struct ubifs_bud, rb); 859 this = rb_parent(this); 860 if (this) { 861 if (this->rb_left == &bud->rb) 862 this->rb_left = NULL; 863 else 864 this->rb_right = NULL; 865 } 866 kfree(bud); 867 } 868 } 869 } 870 871 /** 872 * check_volume_empty - check if the UBI volume is empty. 873 * @c: UBIFS file-system description object 874 * 875 * This function checks if the UBIFS volume is empty by looking if its LEBs are 876 * mapped or not. The result of checking is stored in the @c->empty variable. 877 * Returns zero in case of success and a negative error code in case of 878 * failure. 879 */ 880 static int check_volume_empty(struct ubifs_info *c) 881 { 882 int lnum, err; 883 884 c->empty = 1; 885 for (lnum = 0; lnum < c->leb_cnt; lnum++) { 886 err = ubi_is_mapped(c->ubi, lnum); 887 if (unlikely(err < 0)) 888 return err; 889 if (err == 1) { 890 c->empty = 0; 891 break; 892 } 893 894 cond_resched(); 895 } 896 897 return 0; 898 } 899 900 /* 901 * UBIFS mount options. 902 * 903 * Opt_fast_unmount: do not run a journal commit before un-mounting 904 * Opt_norm_unmount: run a journal commit before un-mounting 905 * Opt_bulk_read: enable bulk-reads 906 * Opt_no_bulk_read: disable bulk-reads 907 * Opt_chk_data_crc: check CRCs when reading data nodes 908 * Opt_no_chk_data_crc: do not check CRCs when reading data nodes 909 * Opt_override_compr: override default compressor 910 * Opt_err: just end of array marker 911 */ 912 enum { 913 Opt_fast_unmount, 914 Opt_norm_unmount, 915 Opt_bulk_read, 916 Opt_no_bulk_read, 917 Opt_chk_data_crc, 918 Opt_no_chk_data_crc, 919 Opt_override_compr, 920 Opt_err, 921 }; 922 923 static const match_table_t tokens = { 924 {Opt_fast_unmount, "fast_unmount"}, 925 {Opt_norm_unmount, "norm_unmount"}, 926 {Opt_bulk_read, "bulk_read"}, 927 {Opt_no_bulk_read, "no_bulk_read"}, 928 {Opt_chk_data_crc, "chk_data_crc"}, 929 {Opt_no_chk_data_crc, "no_chk_data_crc"}, 930 {Opt_override_compr, "compr=%s"}, 931 {Opt_err, NULL}, 932 }; 933 934 /** 935 * parse_standard_option - parse a standard mount option. 936 * @option: the option to parse 937 * 938 * Normally, standard mount options like "sync" are passed to file-systems as 939 * flags. However, when a "rootflags=" kernel boot parameter is used, they may 940 * be present in the options string. This function tries to deal with this 941 * situation and parse standard options. Returns 0 if the option was not 942 * recognized, and the corresponding integer flag if it was. 943 * 944 * UBIFS is only interested in the "sync" option, so do not check for anything 945 * else. 946 */ 947 static int parse_standard_option(const char *option) 948 { 949 ubifs_msg("parse %s", option); 950 if (!strcmp(option, "sync")) 951 return MS_SYNCHRONOUS; 952 return 0; 953 } 954 955 /** 956 * ubifs_parse_options - parse mount parameters. 957 * @c: UBIFS file-system description object 958 * @options: parameters to parse 959 * @is_remount: non-zero if this is FS re-mount 960 * 961 * This function parses UBIFS mount options and returns zero in case success 962 * and a negative error code in case of failure. 963 */ 964 static int ubifs_parse_options(struct ubifs_info *c, char *options, 965 int is_remount) 966 { 967 char *p; 968 substring_t args[MAX_OPT_ARGS]; 969 970 if (!options) 971 return 0; 972 973 while ((p = strsep(&options, ","))) { 974 int token; 975 976 if (!*p) 977 continue; 978 979 token = match_token(p, tokens, args); 980 switch (token) { 981 /* 982 * %Opt_fast_unmount and %Opt_norm_unmount options are ignored. 983 * We accept them in order to be backward-compatible. But this 984 * should be removed at some point. 985 */ 986 case Opt_fast_unmount: 987 c->mount_opts.unmount_mode = 2; 988 break; 989 case Opt_norm_unmount: 990 c->mount_opts.unmount_mode = 1; 991 break; 992 case Opt_bulk_read: 993 c->mount_opts.bulk_read = 2; 994 c->bulk_read = 1; 995 break; 996 case Opt_no_bulk_read: 997 c->mount_opts.bulk_read = 1; 998 c->bulk_read = 0; 999 break; 1000 case Opt_chk_data_crc: 1001 c->mount_opts.chk_data_crc = 2; 1002 c->no_chk_data_crc = 0; 1003 break; 1004 case Opt_no_chk_data_crc: 1005 c->mount_opts.chk_data_crc = 1; 1006 c->no_chk_data_crc = 1; 1007 break; 1008 case Opt_override_compr: 1009 { 1010 char *name = match_strdup(&args[0]); 1011 1012 if (!name) 1013 return -ENOMEM; 1014 if (!strcmp(name, "none")) 1015 c->mount_opts.compr_type = UBIFS_COMPR_NONE; 1016 else if (!strcmp(name, "lzo")) 1017 c->mount_opts.compr_type = UBIFS_COMPR_LZO; 1018 else if (!strcmp(name, "zlib")) 1019 c->mount_opts.compr_type = UBIFS_COMPR_ZLIB; 1020 else { 1021 ubifs_err("unknown compressor \"%s\"", name); 1022 kfree(name); 1023 return -EINVAL; 1024 } 1025 kfree(name); 1026 c->mount_opts.override_compr = 1; 1027 c->default_compr = c->mount_opts.compr_type; 1028 break; 1029 } 1030 default: 1031 { 1032 unsigned long flag; 1033 struct super_block *sb = c->vfs_sb; 1034 1035 flag = parse_standard_option(p); 1036 if (!flag) { 1037 ubifs_err("unrecognized mount option \"%s\" " 1038 "or missing value", p); 1039 return -EINVAL; 1040 } 1041 sb->s_flags |= flag; 1042 break; 1043 } 1044 } 1045 } 1046 1047 return 0; 1048 } 1049 1050 /** 1051 * destroy_journal - destroy journal data structures. 1052 * @c: UBIFS file-system description object 1053 * 1054 * This function destroys journal data structures including those that may have 1055 * been created by recovery functions. 1056 */ 1057 static void destroy_journal(struct ubifs_info *c) 1058 { 1059 while (!list_empty(&c->unclean_leb_list)) { 1060 struct ubifs_unclean_leb *ucleb; 1061 1062 ucleb = list_entry(c->unclean_leb_list.next, 1063 struct ubifs_unclean_leb, list); 1064 list_del(&ucleb->list); 1065 kfree(ucleb); 1066 } 1067 while (!list_empty(&c->old_buds)) { 1068 struct ubifs_bud *bud; 1069 1070 bud = list_entry(c->old_buds.next, struct ubifs_bud, list); 1071 list_del(&bud->list); 1072 kfree(bud); 1073 } 1074 ubifs_destroy_idx_gc(c); 1075 ubifs_destroy_size_tree(c); 1076 ubifs_tnc_close(c); 1077 free_buds(c); 1078 } 1079 1080 /** 1081 * bu_init - initialize bulk-read information. 1082 * @c: UBIFS file-system description object 1083 */ 1084 static void bu_init(struct ubifs_info *c) 1085 { 1086 ubifs_assert(c->bulk_read == 1); 1087 1088 if (c->bu.buf) 1089 return; /* Already initialized */ 1090 1091 again: 1092 c->bu.buf = kmalloc(c->max_bu_buf_len, GFP_KERNEL | __GFP_NOWARN); 1093 if (!c->bu.buf) { 1094 if (c->max_bu_buf_len > UBIFS_KMALLOC_OK) { 1095 c->max_bu_buf_len = UBIFS_KMALLOC_OK; 1096 goto again; 1097 } 1098 1099 /* Just disable bulk-read */ 1100 ubifs_warn("Cannot allocate %d bytes of memory for bulk-read, " 1101 "disabling it", c->max_bu_buf_len); 1102 c->mount_opts.bulk_read = 1; 1103 c->bulk_read = 0; 1104 return; 1105 } 1106 } 1107 1108 /** 1109 * check_free_space - check if there is enough free space to mount. 1110 * @c: UBIFS file-system description object 1111 * 1112 * This function makes sure UBIFS has enough free space to be mounted in 1113 * read/write mode. UBIFS must always have some free space to allow deletions. 1114 */ 1115 static int check_free_space(struct ubifs_info *c) 1116 { 1117 ubifs_assert(c->dark_wm > 0); 1118 if (c->lst.total_free + c->lst.total_dirty < c->dark_wm) { 1119 ubifs_err("insufficient free space to mount in read/write mode"); 1120 dbg_dump_budg(c); 1121 dbg_dump_lprops(c); 1122 return -ENOSPC; 1123 } 1124 return 0; 1125 } 1126 1127 /** 1128 * mount_ubifs - mount UBIFS file-system. 1129 * @c: UBIFS file-system description object 1130 * 1131 * This function mounts UBIFS file system. Returns zero in case of success and 1132 * a negative error code in case of failure. 1133 * 1134 * Note, the function does not de-allocate resources it it fails half way 1135 * through, and the caller has to do this instead. 1136 */ 1137 static int mount_ubifs(struct ubifs_info *c) 1138 { 1139 struct super_block *sb = c->vfs_sb; 1140 int err, mounted_read_only = (sb->s_flags & MS_RDONLY); 1141 long long x; 1142 size_t sz; 1143 1144 err = init_constants_early(c); 1145 if (err) 1146 return err; 1147 1148 err = ubifs_debugging_init(c); 1149 if (err) 1150 return err; 1151 1152 err = check_volume_empty(c); 1153 if (err) 1154 goto out_free; 1155 1156 if (c->empty && (mounted_read_only || c->ro_media)) { 1157 /* 1158 * This UBI volume is empty, and read-only, or the file system 1159 * is mounted read-only - we cannot format it. 1160 */ 1161 ubifs_err("can't format empty UBI volume: read-only %s", 1162 c->ro_media ? "UBI volume" : "mount"); 1163 err = -EROFS; 1164 goto out_free; 1165 } 1166 1167 if (c->ro_media && !mounted_read_only) { 1168 ubifs_err("cannot mount read-write - read-only media"); 1169 err = -EROFS; 1170 goto out_free; 1171 } 1172 1173 /* 1174 * The requirement for the buffer is that it should fit indexing B-tree 1175 * height amount of integers. We assume the height if the TNC tree will 1176 * never exceed 64. 1177 */ 1178 err = -ENOMEM; 1179 c->bottom_up_buf = kmalloc(BOTTOM_UP_HEIGHT * sizeof(int), GFP_KERNEL); 1180 if (!c->bottom_up_buf) 1181 goto out_free; 1182 1183 c->sbuf = vmalloc(c->leb_size); 1184 if (!c->sbuf) 1185 goto out_free; 1186 1187 if (!mounted_read_only) { 1188 c->ileb_buf = vmalloc(c->leb_size); 1189 if (!c->ileb_buf) 1190 goto out_free; 1191 } 1192 1193 if (c->bulk_read == 1) 1194 bu_init(c); 1195 1196 /* 1197 * We have to check all CRCs, even for data nodes, when we mount the FS 1198 * (specifically, when we are replaying). 1199 */ 1200 c->always_chk_crc = 1; 1201 1202 err = ubifs_read_superblock(c); 1203 if (err) 1204 goto out_free; 1205 1206 /* 1207 * Make sure the compressor which is set as default in the superblock 1208 * or overridden by mount options is actually compiled in. 1209 */ 1210 if (!ubifs_compr_present(c->default_compr)) { 1211 ubifs_err("'compressor \"%s\" is not compiled in", 1212 ubifs_compr_name(c->default_compr)); 1213 err = -ENOTSUPP; 1214 goto out_free; 1215 } 1216 1217 err = init_constants_sb(c); 1218 if (err) 1219 goto out_free; 1220 1221 sz = ALIGN(c->max_idx_node_sz, c->min_io_size); 1222 sz = ALIGN(sz + c->max_idx_node_sz, c->min_io_size); 1223 c->cbuf = kmalloc(sz, GFP_NOFS); 1224 if (!c->cbuf) { 1225 err = -ENOMEM; 1226 goto out_free; 1227 } 1228 1229 sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num, c->vi.vol_id); 1230 if (!mounted_read_only) { 1231 err = alloc_wbufs(c); 1232 if (err) 1233 goto out_cbuf; 1234 1235 /* Create background thread */ 1236 c->bgt = kthread_create(ubifs_bg_thread, c, "%s", c->bgt_name); 1237 if (IS_ERR(c->bgt)) { 1238 err = PTR_ERR(c->bgt); 1239 c->bgt = NULL; 1240 ubifs_err("cannot spawn \"%s\", error %d", 1241 c->bgt_name, err); 1242 goto out_wbufs; 1243 } 1244 wake_up_process(c->bgt); 1245 } 1246 1247 err = ubifs_read_master(c); 1248 if (err) 1249 goto out_master; 1250 1251 init_constants_master(c); 1252 1253 if ((c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY)) != 0) { 1254 ubifs_msg("recovery needed"); 1255 c->need_recovery = 1; 1256 if (!mounted_read_only) { 1257 err = ubifs_recover_inl_heads(c, c->sbuf); 1258 if (err) 1259 goto out_master; 1260 } 1261 } else if (!mounted_read_only) { 1262 /* 1263 * Set the "dirty" flag so that if we reboot uncleanly we 1264 * will notice this immediately on the next mount. 1265 */ 1266 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY); 1267 err = ubifs_write_master(c); 1268 if (err) 1269 goto out_master; 1270 } 1271 1272 err = ubifs_lpt_init(c, 1, !mounted_read_only); 1273 if (err) 1274 goto out_lpt; 1275 1276 err = dbg_check_idx_size(c, c->old_idx_sz); 1277 if (err) 1278 goto out_lpt; 1279 1280 err = ubifs_replay_journal(c); 1281 if (err) 1282 goto out_journal; 1283 1284 /* Calculate 'min_idx_lebs' after journal replay */ 1285 c->min_idx_lebs = ubifs_calc_min_idx_lebs(c); 1286 1287 err = ubifs_mount_orphans(c, c->need_recovery, mounted_read_only); 1288 if (err) 1289 goto out_orphans; 1290 1291 if (!mounted_read_only) { 1292 int lnum; 1293 1294 err = check_free_space(c); 1295 if (err) 1296 goto out_orphans; 1297 1298 /* Check for enough log space */ 1299 lnum = c->lhead_lnum + 1; 1300 if (lnum >= UBIFS_LOG_LNUM + c->log_lebs) 1301 lnum = UBIFS_LOG_LNUM; 1302 if (lnum == c->ltail_lnum) { 1303 err = ubifs_consolidate_log(c); 1304 if (err) 1305 goto out_orphans; 1306 } 1307 1308 if (c->need_recovery) { 1309 err = ubifs_recover_size(c); 1310 if (err) 1311 goto out_orphans; 1312 err = ubifs_rcvry_gc_commit(c); 1313 } else { 1314 err = take_gc_lnum(c); 1315 if (err) 1316 goto out_orphans; 1317 1318 /* 1319 * GC LEB may contain garbage if there was an unclean 1320 * reboot, and it should be un-mapped. 1321 */ 1322 err = ubifs_leb_unmap(c, c->gc_lnum); 1323 if (err) 1324 return err; 1325 } 1326 1327 err = dbg_check_lprops(c); 1328 if (err) 1329 goto out_orphans; 1330 } else if (c->need_recovery) { 1331 err = ubifs_recover_size(c); 1332 if (err) 1333 goto out_orphans; 1334 } else { 1335 /* 1336 * Even if we mount read-only, we have to set space in GC LEB 1337 * to proper value because this affects UBIFS free space 1338 * reporting. We do not want to have a situation when 1339 * re-mounting from R/O to R/W changes amount of free space. 1340 */ 1341 err = take_gc_lnum(c); 1342 if (err) 1343 goto out_orphans; 1344 } 1345 1346 spin_lock(&ubifs_infos_lock); 1347 list_add_tail(&c->infos_list, &ubifs_infos); 1348 spin_unlock(&ubifs_infos_lock); 1349 1350 if (c->need_recovery) { 1351 if (mounted_read_only) 1352 ubifs_msg("recovery deferred"); 1353 else { 1354 c->need_recovery = 0; 1355 ubifs_msg("recovery completed"); 1356 /* 1357 * GC LEB has to be empty and taken at this point. But 1358 * the journal head LEBs may also be accounted as 1359 * "empty taken" if they are empty. 1360 */ 1361 ubifs_assert(c->lst.taken_empty_lebs > 0); 1362 } 1363 } else 1364 ubifs_assert(c->lst.taken_empty_lebs > 0); 1365 1366 err = dbg_check_filesystem(c); 1367 if (err) 1368 goto out_infos; 1369 1370 err = dbg_debugfs_init_fs(c); 1371 if (err) 1372 goto out_infos; 1373 1374 c->always_chk_crc = 0; 1375 1376 ubifs_msg("mounted UBI device %d, volume %d, name \"%s\"", 1377 c->vi.ubi_num, c->vi.vol_id, c->vi.name); 1378 if (mounted_read_only) 1379 ubifs_msg("mounted read-only"); 1380 x = (long long)c->main_lebs * c->leb_size; 1381 ubifs_msg("file system size: %lld bytes (%lld KiB, %lld MiB, %d " 1382 "LEBs)", x, x >> 10, x >> 20, c->main_lebs); 1383 x = (long long)c->log_lebs * c->leb_size + c->max_bud_bytes; 1384 ubifs_msg("journal size: %lld bytes (%lld KiB, %lld MiB, %d " 1385 "LEBs)", x, x >> 10, x >> 20, c->log_lebs + c->max_bud_cnt); 1386 ubifs_msg("media format: w%d/r%d (latest is w%d/r%d)", 1387 c->fmt_version, c->ro_compat_version, 1388 UBIFS_FORMAT_VERSION, UBIFS_RO_COMPAT_VERSION); 1389 ubifs_msg("default compressor: %s", ubifs_compr_name(c->default_compr)); 1390 ubifs_msg("reserved for root: %llu bytes (%llu KiB)", 1391 c->report_rp_size, c->report_rp_size >> 10); 1392 1393 dbg_msg("compiled on: " __DATE__ " at " __TIME__); 1394 dbg_msg("min. I/O unit size: %d bytes", c->min_io_size); 1395 dbg_msg("LEB size: %d bytes (%d KiB)", 1396 c->leb_size, c->leb_size >> 10); 1397 dbg_msg("data journal heads: %d", 1398 c->jhead_cnt - NONDATA_JHEADS_CNT); 1399 dbg_msg("UUID: %02X%02X%02X%02X-%02X%02X" 1400 "-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X", 1401 c->uuid[0], c->uuid[1], c->uuid[2], c->uuid[3], 1402 c->uuid[4], c->uuid[5], c->uuid[6], c->uuid[7], 1403 c->uuid[8], c->uuid[9], c->uuid[10], c->uuid[11], 1404 c->uuid[12], c->uuid[13], c->uuid[14], c->uuid[15]); 1405 dbg_msg("big_lpt %d", c->big_lpt); 1406 dbg_msg("log LEBs: %d (%d - %d)", 1407 c->log_lebs, UBIFS_LOG_LNUM, c->log_last); 1408 dbg_msg("LPT area LEBs: %d (%d - %d)", 1409 c->lpt_lebs, c->lpt_first, c->lpt_last); 1410 dbg_msg("orphan area LEBs: %d (%d - %d)", 1411 c->orph_lebs, c->orph_first, c->orph_last); 1412 dbg_msg("main area LEBs: %d (%d - %d)", 1413 c->main_lebs, c->main_first, c->leb_cnt - 1); 1414 dbg_msg("index LEBs: %d", c->lst.idx_lebs); 1415 dbg_msg("total index bytes: %lld (%lld KiB, %lld MiB)", 1416 c->old_idx_sz, c->old_idx_sz >> 10, c->old_idx_sz >> 20); 1417 dbg_msg("key hash type: %d", c->key_hash_type); 1418 dbg_msg("tree fanout: %d", c->fanout); 1419 dbg_msg("reserved GC LEB: %d", c->gc_lnum); 1420 dbg_msg("first main LEB: %d", c->main_first); 1421 dbg_msg("max. znode size %d", c->max_znode_sz); 1422 dbg_msg("max. index node size %d", c->max_idx_node_sz); 1423 dbg_msg("node sizes: data %zu, inode %zu, dentry %zu", 1424 UBIFS_DATA_NODE_SZ, UBIFS_INO_NODE_SZ, UBIFS_DENT_NODE_SZ); 1425 dbg_msg("node sizes: trun %zu, sb %zu, master %zu", 1426 UBIFS_TRUN_NODE_SZ, UBIFS_SB_NODE_SZ, UBIFS_MST_NODE_SZ); 1427 dbg_msg("node sizes: ref %zu, cmt. start %zu, orph %zu", 1428 UBIFS_REF_NODE_SZ, UBIFS_CS_NODE_SZ, UBIFS_ORPH_NODE_SZ); 1429 dbg_msg("max. node sizes: data %zu, inode %zu dentry %zu", 1430 UBIFS_MAX_DATA_NODE_SZ, UBIFS_MAX_INO_NODE_SZ, 1431 UBIFS_MAX_DENT_NODE_SZ); 1432 dbg_msg("dead watermark: %d", c->dead_wm); 1433 dbg_msg("dark watermark: %d", c->dark_wm); 1434 dbg_msg("LEB overhead: %d", c->leb_overhead); 1435 x = (long long)c->main_lebs * c->dark_wm; 1436 dbg_msg("max. dark space: %lld (%lld KiB, %lld MiB)", 1437 x, x >> 10, x >> 20); 1438 dbg_msg("maximum bud bytes: %lld (%lld KiB, %lld MiB)", 1439 c->max_bud_bytes, c->max_bud_bytes >> 10, 1440 c->max_bud_bytes >> 20); 1441 dbg_msg("BG commit bud bytes: %lld (%lld KiB, %lld MiB)", 1442 c->bg_bud_bytes, c->bg_bud_bytes >> 10, 1443 c->bg_bud_bytes >> 20); 1444 dbg_msg("current bud bytes %lld (%lld KiB, %lld MiB)", 1445 c->bud_bytes, c->bud_bytes >> 10, c->bud_bytes >> 20); 1446 dbg_msg("max. seq. number: %llu", c->max_sqnum); 1447 dbg_msg("commit number: %llu", c->cmt_no); 1448 1449 return 0; 1450 1451 out_infos: 1452 spin_lock(&ubifs_infos_lock); 1453 list_del(&c->infos_list); 1454 spin_unlock(&ubifs_infos_lock); 1455 out_orphans: 1456 free_orphans(c); 1457 out_journal: 1458 destroy_journal(c); 1459 out_lpt: 1460 ubifs_lpt_free(c, 0); 1461 out_master: 1462 kfree(c->mst_node); 1463 kfree(c->rcvrd_mst_node); 1464 if (c->bgt) 1465 kthread_stop(c->bgt); 1466 out_wbufs: 1467 free_wbufs(c); 1468 out_cbuf: 1469 kfree(c->cbuf); 1470 out_free: 1471 kfree(c->bu.buf); 1472 vfree(c->ileb_buf); 1473 vfree(c->sbuf); 1474 kfree(c->bottom_up_buf); 1475 ubifs_debugging_exit(c); 1476 return err; 1477 } 1478 1479 /** 1480 * ubifs_umount - un-mount UBIFS file-system. 1481 * @c: UBIFS file-system description object 1482 * 1483 * Note, this function is called to free allocated resourced when un-mounting, 1484 * as well as free resources when an error occurred while we were half way 1485 * through mounting (error path cleanup function). So it has to make sure the 1486 * resource was actually allocated before freeing it. 1487 */ 1488 static void ubifs_umount(struct ubifs_info *c) 1489 { 1490 dbg_gen("un-mounting UBI device %d, volume %d", c->vi.ubi_num, 1491 c->vi.vol_id); 1492 1493 dbg_debugfs_exit_fs(c); 1494 spin_lock(&ubifs_infos_lock); 1495 list_del(&c->infos_list); 1496 spin_unlock(&ubifs_infos_lock); 1497 1498 if (c->bgt) 1499 kthread_stop(c->bgt); 1500 1501 destroy_journal(c); 1502 free_wbufs(c); 1503 free_orphans(c); 1504 ubifs_lpt_free(c, 0); 1505 1506 kfree(c->cbuf); 1507 kfree(c->rcvrd_mst_node); 1508 kfree(c->mst_node); 1509 kfree(c->bu.buf); 1510 vfree(c->ileb_buf); 1511 vfree(c->sbuf); 1512 kfree(c->bottom_up_buf); 1513 ubifs_debugging_exit(c); 1514 } 1515 1516 /** 1517 * ubifs_remount_rw - re-mount in read-write mode. 1518 * @c: UBIFS file-system description object 1519 * 1520 * UBIFS avoids allocating many unnecessary resources when mounted in read-only 1521 * mode. This function allocates the needed resources and re-mounts UBIFS in 1522 * read-write mode. 1523 */ 1524 static int ubifs_remount_rw(struct ubifs_info *c) 1525 { 1526 int err, lnum; 1527 1528 if (c->rw_incompat) { 1529 ubifs_err("the file-system is not R/W-compatible"); 1530 ubifs_msg("on-flash format version is w%d/r%d, but software " 1531 "only supports up to version w%d/r%d", c->fmt_version, 1532 c->ro_compat_version, UBIFS_FORMAT_VERSION, 1533 UBIFS_RO_COMPAT_VERSION); 1534 return -EROFS; 1535 } 1536 1537 mutex_lock(&c->umount_mutex); 1538 dbg_save_space_info(c); 1539 c->remounting_rw = 1; 1540 c->always_chk_crc = 1; 1541 1542 err = check_free_space(c); 1543 if (err) 1544 goto out; 1545 1546 if (c->old_leb_cnt != c->leb_cnt) { 1547 struct ubifs_sb_node *sup; 1548 1549 sup = ubifs_read_sb_node(c); 1550 if (IS_ERR(sup)) { 1551 err = PTR_ERR(sup); 1552 goto out; 1553 } 1554 sup->leb_cnt = cpu_to_le32(c->leb_cnt); 1555 err = ubifs_write_sb_node(c, sup); 1556 if (err) 1557 goto out; 1558 } 1559 1560 if (c->need_recovery) { 1561 ubifs_msg("completing deferred recovery"); 1562 err = ubifs_write_rcvrd_mst_node(c); 1563 if (err) 1564 goto out; 1565 err = ubifs_recover_size(c); 1566 if (err) 1567 goto out; 1568 err = ubifs_clean_lebs(c, c->sbuf); 1569 if (err) 1570 goto out; 1571 err = ubifs_recover_inl_heads(c, c->sbuf); 1572 if (err) 1573 goto out; 1574 } else { 1575 /* A readonly mount is not allowed to have orphans */ 1576 ubifs_assert(c->tot_orphans == 0); 1577 err = ubifs_clear_orphans(c); 1578 if (err) 1579 goto out; 1580 } 1581 1582 if (!(c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY))) { 1583 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY); 1584 err = ubifs_write_master(c); 1585 if (err) 1586 goto out; 1587 } 1588 1589 c->ileb_buf = vmalloc(c->leb_size); 1590 if (!c->ileb_buf) { 1591 err = -ENOMEM; 1592 goto out; 1593 } 1594 1595 err = ubifs_lpt_init(c, 0, 1); 1596 if (err) 1597 goto out; 1598 1599 err = alloc_wbufs(c); 1600 if (err) 1601 goto out; 1602 1603 ubifs_create_buds_lists(c); 1604 1605 /* Create background thread */ 1606 c->bgt = kthread_create(ubifs_bg_thread, c, "%s", c->bgt_name); 1607 if (IS_ERR(c->bgt)) { 1608 err = PTR_ERR(c->bgt); 1609 c->bgt = NULL; 1610 ubifs_err("cannot spawn \"%s\", error %d", 1611 c->bgt_name, err); 1612 goto out; 1613 } 1614 wake_up_process(c->bgt); 1615 1616 c->orph_buf = vmalloc(c->leb_size); 1617 if (!c->orph_buf) { 1618 err = -ENOMEM; 1619 goto out; 1620 } 1621 1622 /* Check for enough log space */ 1623 lnum = c->lhead_lnum + 1; 1624 if (lnum >= UBIFS_LOG_LNUM + c->log_lebs) 1625 lnum = UBIFS_LOG_LNUM; 1626 if (lnum == c->ltail_lnum) { 1627 err = ubifs_consolidate_log(c); 1628 if (err) 1629 goto out; 1630 } 1631 1632 if (c->need_recovery) 1633 err = ubifs_rcvry_gc_commit(c); 1634 else 1635 err = ubifs_leb_unmap(c, c->gc_lnum); 1636 if (err) 1637 goto out; 1638 1639 if (c->need_recovery) { 1640 c->need_recovery = 0; 1641 ubifs_msg("deferred recovery completed"); 1642 } 1643 1644 dbg_gen("re-mounted read-write"); 1645 c->vfs_sb->s_flags &= ~MS_RDONLY; 1646 c->remounting_rw = 0; 1647 c->always_chk_crc = 0; 1648 err = dbg_check_space_info(c); 1649 mutex_unlock(&c->umount_mutex); 1650 return err; 1651 1652 out: 1653 vfree(c->orph_buf); 1654 c->orph_buf = NULL; 1655 if (c->bgt) { 1656 kthread_stop(c->bgt); 1657 c->bgt = NULL; 1658 } 1659 free_wbufs(c); 1660 vfree(c->ileb_buf); 1661 c->ileb_buf = NULL; 1662 ubifs_lpt_free(c, 1); 1663 c->remounting_rw = 0; 1664 c->always_chk_crc = 0; 1665 mutex_unlock(&c->umount_mutex); 1666 return err; 1667 } 1668 1669 /** 1670 * ubifs_remount_ro - re-mount in read-only mode. 1671 * @c: UBIFS file-system description object 1672 * 1673 * We assume VFS has stopped writing. Possibly the background thread could be 1674 * running a commit, however kthread_stop will wait in that case. 1675 */ 1676 static void ubifs_remount_ro(struct ubifs_info *c) 1677 { 1678 int i, err; 1679 1680 ubifs_assert(!c->need_recovery); 1681 ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY)); 1682 1683 mutex_lock(&c->umount_mutex); 1684 if (c->bgt) { 1685 kthread_stop(c->bgt); 1686 c->bgt = NULL; 1687 } 1688 1689 dbg_save_space_info(c); 1690 1691 for (i = 0; i < c->jhead_cnt; i++) { 1692 ubifs_wbuf_sync(&c->jheads[i].wbuf); 1693 hrtimer_cancel(&c->jheads[i].wbuf.timer); 1694 } 1695 1696 c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY); 1697 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS); 1698 c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum); 1699 err = ubifs_write_master(c); 1700 if (err) 1701 ubifs_ro_mode(c, err); 1702 1703 free_wbufs(c); 1704 vfree(c->orph_buf); 1705 c->orph_buf = NULL; 1706 vfree(c->ileb_buf); 1707 c->ileb_buf = NULL; 1708 ubifs_lpt_free(c, 1); 1709 err = dbg_check_space_info(c); 1710 if (err) 1711 ubifs_ro_mode(c, err); 1712 mutex_unlock(&c->umount_mutex); 1713 } 1714 1715 static void ubifs_put_super(struct super_block *sb) 1716 { 1717 int i; 1718 struct ubifs_info *c = sb->s_fs_info; 1719 1720 ubifs_msg("un-mount UBI device %d, volume %d", c->vi.ubi_num, 1721 c->vi.vol_id); 1722 1723 lock_kernel(); 1724 1725 /* 1726 * The following asserts are only valid if there has not been a failure 1727 * of the media. For example, there will be dirty inodes if we failed 1728 * to write them back because of I/O errors. 1729 */ 1730 ubifs_assert(atomic_long_read(&c->dirty_pg_cnt) == 0); 1731 ubifs_assert(c->budg_idx_growth == 0); 1732 ubifs_assert(c->budg_dd_growth == 0); 1733 ubifs_assert(c->budg_data_growth == 0); 1734 1735 /* 1736 * The 'c->umount_lock' prevents races between UBIFS memory shrinker 1737 * and file system un-mount. Namely, it prevents the shrinker from 1738 * picking this superblock for shrinking - it will be just skipped if 1739 * the mutex is locked. 1740 */ 1741 mutex_lock(&c->umount_mutex); 1742 if (!(c->vfs_sb->s_flags & MS_RDONLY)) { 1743 /* 1744 * First of all kill the background thread to make sure it does 1745 * not interfere with un-mounting and freeing resources. 1746 */ 1747 if (c->bgt) { 1748 kthread_stop(c->bgt); 1749 c->bgt = NULL; 1750 } 1751 1752 /* Synchronize write-buffers */ 1753 if (c->jheads) 1754 for (i = 0; i < c->jhead_cnt; i++) 1755 ubifs_wbuf_sync(&c->jheads[i].wbuf); 1756 1757 /* 1758 * On fatal errors c->ro_media is set to 1, in which case we do 1759 * not write the master node. 1760 */ 1761 if (!c->ro_media) { 1762 /* 1763 * We are being cleanly unmounted which means the 1764 * orphans were killed - indicate this in the master 1765 * node. Also save the reserved GC LEB number. 1766 */ 1767 int err; 1768 1769 c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY); 1770 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS); 1771 c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum); 1772 err = ubifs_write_master(c); 1773 if (err) 1774 /* 1775 * Recovery will attempt to fix the master area 1776 * next mount, so we just print a message and 1777 * continue to unmount normally. 1778 */ 1779 ubifs_err("failed to write master node, " 1780 "error %d", err); 1781 } 1782 } 1783 1784 ubifs_umount(c); 1785 bdi_destroy(&c->bdi); 1786 ubi_close_volume(c->ubi); 1787 mutex_unlock(&c->umount_mutex); 1788 kfree(c); 1789 1790 unlock_kernel(); 1791 } 1792 1793 static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data) 1794 { 1795 int err; 1796 struct ubifs_info *c = sb->s_fs_info; 1797 1798 dbg_gen("old flags %#lx, new flags %#x", sb->s_flags, *flags); 1799 1800 err = ubifs_parse_options(c, data, 1); 1801 if (err) { 1802 ubifs_err("invalid or unknown remount parameter"); 1803 return err; 1804 } 1805 1806 lock_kernel(); 1807 if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) { 1808 if (c->ro_media) { 1809 ubifs_msg("cannot re-mount due to prior errors"); 1810 unlock_kernel(); 1811 return -EROFS; 1812 } 1813 err = ubifs_remount_rw(c); 1814 if (err) { 1815 unlock_kernel(); 1816 return err; 1817 } 1818 } else if (!(sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY)) { 1819 if (c->ro_media) { 1820 ubifs_msg("cannot re-mount due to prior errors"); 1821 unlock_kernel(); 1822 return -EROFS; 1823 } 1824 ubifs_remount_ro(c); 1825 } 1826 1827 if (c->bulk_read == 1) 1828 bu_init(c); 1829 else { 1830 dbg_gen("disable bulk-read"); 1831 kfree(c->bu.buf); 1832 c->bu.buf = NULL; 1833 } 1834 1835 ubifs_assert(c->lst.taken_empty_lebs > 0); 1836 unlock_kernel(); 1837 return 0; 1838 } 1839 1840 const struct super_operations ubifs_super_operations = { 1841 .alloc_inode = ubifs_alloc_inode, 1842 .destroy_inode = ubifs_destroy_inode, 1843 .put_super = ubifs_put_super, 1844 .write_inode = ubifs_write_inode, 1845 .delete_inode = ubifs_delete_inode, 1846 .statfs = ubifs_statfs, 1847 .dirty_inode = ubifs_dirty_inode, 1848 .remount_fs = ubifs_remount_fs, 1849 .show_options = ubifs_show_options, 1850 .sync_fs = ubifs_sync_fs, 1851 }; 1852 1853 /** 1854 * open_ubi - parse UBI device name string and open the UBI device. 1855 * @name: UBI volume name 1856 * @mode: UBI volume open mode 1857 * 1858 * There are several ways to specify UBI volumes when mounting UBIFS: 1859 * o ubiX_Y - UBI device number X, volume Y; 1860 * o ubiY - UBI device number 0, volume Y; 1861 * o ubiX:NAME - mount UBI device X, volume with name NAME; 1862 * o ubi:NAME - mount UBI device 0, volume with name NAME. 1863 * 1864 * Alternative '!' separator may be used instead of ':' (because some shells 1865 * like busybox may interpret ':' as an NFS host name separator). This function 1866 * returns ubi volume object in case of success and a negative error code in 1867 * case of failure. 1868 */ 1869 static struct ubi_volume_desc *open_ubi(const char *name, int mode) 1870 { 1871 int dev, vol; 1872 char *endptr; 1873 1874 if (name[0] != 'u' || name[1] != 'b' || name[2] != 'i') 1875 return ERR_PTR(-EINVAL); 1876 1877 /* ubi:NAME method */ 1878 if ((name[3] == ':' || name[3] == '!') && name[4] != '\0') 1879 return ubi_open_volume_nm(0, name + 4, mode); 1880 1881 if (!isdigit(name[3])) 1882 return ERR_PTR(-EINVAL); 1883 1884 dev = simple_strtoul(name + 3, &endptr, 0); 1885 1886 /* ubiY method */ 1887 if (*endptr == '\0') 1888 return ubi_open_volume(0, dev, mode); 1889 1890 /* ubiX_Y method */ 1891 if (*endptr == '_' && isdigit(endptr[1])) { 1892 vol = simple_strtoul(endptr + 1, &endptr, 0); 1893 if (*endptr != '\0') 1894 return ERR_PTR(-EINVAL); 1895 return ubi_open_volume(dev, vol, mode); 1896 } 1897 1898 /* ubiX:NAME method */ 1899 if ((*endptr == ':' || *endptr == '!') && endptr[1] != '\0') 1900 return ubi_open_volume_nm(dev, ++endptr, mode); 1901 1902 return ERR_PTR(-EINVAL); 1903 } 1904 1905 static int ubifs_fill_super(struct super_block *sb, void *data, int silent) 1906 { 1907 struct ubi_volume_desc *ubi = sb->s_fs_info; 1908 struct ubifs_info *c; 1909 struct inode *root; 1910 int err; 1911 1912 c = kzalloc(sizeof(struct ubifs_info), GFP_KERNEL); 1913 if (!c) 1914 return -ENOMEM; 1915 1916 spin_lock_init(&c->cnt_lock); 1917 spin_lock_init(&c->cs_lock); 1918 spin_lock_init(&c->buds_lock); 1919 spin_lock_init(&c->space_lock); 1920 spin_lock_init(&c->orphan_lock); 1921 init_rwsem(&c->commit_sem); 1922 mutex_init(&c->lp_mutex); 1923 mutex_init(&c->tnc_mutex); 1924 mutex_init(&c->log_mutex); 1925 mutex_init(&c->mst_mutex); 1926 mutex_init(&c->umount_mutex); 1927 mutex_init(&c->bu_mutex); 1928 init_waitqueue_head(&c->cmt_wq); 1929 c->buds = RB_ROOT; 1930 c->old_idx = RB_ROOT; 1931 c->size_tree = RB_ROOT; 1932 c->orph_tree = RB_ROOT; 1933 INIT_LIST_HEAD(&c->infos_list); 1934 INIT_LIST_HEAD(&c->idx_gc); 1935 INIT_LIST_HEAD(&c->replay_list); 1936 INIT_LIST_HEAD(&c->replay_buds); 1937 INIT_LIST_HEAD(&c->uncat_list); 1938 INIT_LIST_HEAD(&c->empty_list); 1939 INIT_LIST_HEAD(&c->freeable_list); 1940 INIT_LIST_HEAD(&c->frdi_idx_list); 1941 INIT_LIST_HEAD(&c->unclean_leb_list); 1942 INIT_LIST_HEAD(&c->old_buds); 1943 INIT_LIST_HEAD(&c->orph_list); 1944 INIT_LIST_HEAD(&c->orph_new); 1945 1946 c->vfs_sb = sb; 1947 c->highest_inum = UBIFS_FIRST_INO; 1948 c->lhead_lnum = c->ltail_lnum = UBIFS_LOG_LNUM; 1949 1950 ubi_get_volume_info(ubi, &c->vi); 1951 ubi_get_device_info(c->vi.ubi_num, &c->di); 1952 1953 /* Re-open the UBI device in read-write mode */ 1954 c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READWRITE); 1955 if (IS_ERR(c->ubi)) { 1956 err = PTR_ERR(c->ubi); 1957 goto out_free; 1958 } 1959 1960 /* 1961 * UBIFS provides 'backing_dev_info' in order to disable read-ahead. For 1962 * UBIFS, I/O is not deferred, it is done immediately in readpage, 1963 * which means the user would have to wait not just for their own I/O 1964 * but the read-ahead I/O as well i.e. completely pointless. 1965 * 1966 * Read-ahead will be disabled because @c->bdi.ra_pages is 0. 1967 */ 1968 c->bdi.name = "ubifs", 1969 c->bdi.capabilities = BDI_CAP_MAP_COPY; 1970 c->bdi.unplug_io_fn = default_unplug_io_fn; 1971 err = bdi_init(&c->bdi); 1972 if (err) 1973 goto out_close; 1974 err = bdi_register(&c->bdi, NULL, "ubifs_%d_%d", 1975 c->vi.ubi_num, c->vi.vol_id); 1976 if (err) 1977 goto out_bdi; 1978 1979 err = ubifs_parse_options(c, data, 0); 1980 if (err) 1981 goto out_bdi; 1982 1983 sb->s_bdi = &c->bdi; 1984 sb->s_fs_info = c; 1985 sb->s_magic = UBIFS_SUPER_MAGIC; 1986 sb->s_blocksize = UBIFS_BLOCK_SIZE; 1987 sb->s_blocksize_bits = UBIFS_BLOCK_SHIFT; 1988 sb->s_maxbytes = c->max_inode_sz = key_max_inode_size(c); 1989 if (c->max_inode_sz > MAX_LFS_FILESIZE) 1990 sb->s_maxbytes = c->max_inode_sz = MAX_LFS_FILESIZE; 1991 sb->s_op = &ubifs_super_operations; 1992 1993 mutex_lock(&c->umount_mutex); 1994 err = mount_ubifs(c); 1995 if (err) { 1996 ubifs_assert(err < 0); 1997 goto out_unlock; 1998 } 1999 2000 /* Read the root inode */ 2001 root = ubifs_iget(sb, UBIFS_ROOT_INO); 2002 if (IS_ERR(root)) { 2003 err = PTR_ERR(root); 2004 goto out_umount; 2005 } 2006 2007 sb->s_root = d_alloc_root(root); 2008 if (!sb->s_root) 2009 goto out_iput; 2010 2011 mutex_unlock(&c->umount_mutex); 2012 return 0; 2013 2014 out_iput: 2015 iput(root); 2016 out_umount: 2017 ubifs_umount(c); 2018 out_unlock: 2019 mutex_unlock(&c->umount_mutex); 2020 out_bdi: 2021 bdi_destroy(&c->bdi); 2022 out_close: 2023 ubi_close_volume(c->ubi); 2024 out_free: 2025 kfree(c); 2026 return err; 2027 } 2028 2029 static int sb_test(struct super_block *sb, void *data) 2030 { 2031 dev_t *dev = data; 2032 struct ubifs_info *c = sb->s_fs_info; 2033 2034 return c->vi.cdev == *dev; 2035 } 2036 2037 static int ubifs_get_sb(struct file_system_type *fs_type, int flags, 2038 const char *name, void *data, struct vfsmount *mnt) 2039 { 2040 struct ubi_volume_desc *ubi; 2041 struct ubi_volume_info vi; 2042 struct super_block *sb; 2043 int err; 2044 2045 dbg_gen("name %s, flags %#x", name, flags); 2046 2047 /* 2048 * Get UBI device number and volume ID. Mount it read-only so far 2049 * because this might be a new mount point, and UBI allows only one 2050 * read-write user at a time. 2051 */ 2052 ubi = open_ubi(name, UBI_READONLY); 2053 if (IS_ERR(ubi)) { 2054 ubifs_err("cannot open \"%s\", error %d", 2055 name, (int)PTR_ERR(ubi)); 2056 return PTR_ERR(ubi); 2057 } 2058 ubi_get_volume_info(ubi, &vi); 2059 2060 dbg_gen("opened ubi%d_%d", vi.ubi_num, vi.vol_id); 2061 2062 sb = sget(fs_type, &sb_test, &set_anon_super, &vi.cdev); 2063 if (IS_ERR(sb)) { 2064 err = PTR_ERR(sb); 2065 goto out_close; 2066 } 2067 2068 if (sb->s_root) { 2069 /* A new mount point for already mounted UBIFS */ 2070 dbg_gen("this ubi volume is already mounted"); 2071 if ((flags ^ sb->s_flags) & MS_RDONLY) { 2072 err = -EBUSY; 2073 goto out_deact; 2074 } 2075 } else { 2076 sb->s_flags = flags; 2077 /* 2078 * Pass 'ubi' to 'fill_super()' in sb->s_fs_info where it is 2079 * replaced by 'c'. 2080 */ 2081 sb->s_fs_info = ubi; 2082 err = ubifs_fill_super(sb, data, flags & MS_SILENT ? 1 : 0); 2083 if (err) 2084 goto out_deact; 2085 /* We do not support atime */ 2086 sb->s_flags |= MS_ACTIVE | MS_NOATIME; 2087 } 2088 2089 /* 'fill_super()' opens ubi again so we must close it here */ 2090 ubi_close_volume(ubi); 2091 2092 simple_set_mnt(mnt, sb); 2093 return 0; 2094 2095 out_deact: 2096 deactivate_locked_super(sb); 2097 out_close: 2098 ubi_close_volume(ubi); 2099 return err; 2100 } 2101 2102 static struct file_system_type ubifs_fs_type = { 2103 .name = "ubifs", 2104 .owner = THIS_MODULE, 2105 .get_sb = ubifs_get_sb, 2106 .kill_sb = kill_anon_super, 2107 }; 2108 2109 /* 2110 * Inode slab cache constructor. 2111 */ 2112 static void inode_slab_ctor(void *obj) 2113 { 2114 struct ubifs_inode *ui = obj; 2115 inode_init_once(&ui->vfs_inode); 2116 } 2117 2118 static int __init ubifs_init(void) 2119 { 2120 int err; 2121 2122 BUILD_BUG_ON(sizeof(struct ubifs_ch) != 24); 2123 2124 /* Make sure node sizes are 8-byte aligned */ 2125 BUILD_BUG_ON(UBIFS_CH_SZ & 7); 2126 BUILD_BUG_ON(UBIFS_INO_NODE_SZ & 7); 2127 BUILD_BUG_ON(UBIFS_DENT_NODE_SZ & 7); 2128 BUILD_BUG_ON(UBIFS_XENT_NODE_SZ & 7); 2129 BUILD_BUG_ON(UBIFS_DATA_NODE_SZ & 7); 2130 BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ & 7); 2131 BUILD_BUG_ON(UBIFS_SB_NODE_SZ & 7); 2132 BUILD_BUG_ON(UBIFS_MST_NODE_SZ & 7); 2133 BUILD_BUG_ON(UBIFS_REF_NODE_SZ & 7); 2134 BUILD_BUG_ON(UBIFS_CS_NODE_SZ & 7); 2135 BUILD_BUG_ON(UBIFS_ORPH_NODE_SZ & 7); 2136 2137 BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ & 7); 2138 BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ & 7); 2139 BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ & 7); 2140 BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ & 7); 2141 BUILD_BUG_ON(UBIFS_MAX_NODE_SZ & 7); 2142 BUILD_BUG_ON(MIN_WRITE_SZ & 7); 2143 2144 /* Check min. node size */ 2145 BUILD_BUG_ON(UBIFS_INO_NODE_SZ < MIN_WRITE_SZ); 2146 BUILD_BUG_ON(UBIFS_DENT_NODE_SZ < MIN_WRITE_SZ); 2147 BUILD_BUG_ON(UBIFS_XENT_NODE_SZ < MIN_WRITE_SZ); 2148 BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ < MIN_WRITE_SZ); 2149 2150 BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ > UBIFS_MAX_NODE_SZ); 2151 BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ > UBIFS_MAX_NODE_SZ); 2152 BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ > UBIFS_MAX_NODE_SZ); 2153 BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ > UBIFS_MAX_NODE_SZ); 2154 2155 /* Defined node sizes */ 2156 BUILD_BUG_ON(UBIFS_SB_NODE_SZ != 4096); 2157 BUILD_BUG_ON(UBIFS_MST_NODE_SZ != 512); 2158 BUILD_BUG_ON(UBIFS_INO_NODE_SZ != 160); 2159 BUILD_BUG_ON(UBIFS_REF_NODE_SZ != 64); 2160 2161 /* 2162 * We use 2 bit wide bit-fields to store compression type, which should 2163 * be amended if more compressors are added. The bit-fields are: 2164 * @compr_type in 'struct ubifs_inode', @default_compr in 2165 * 'struct ubifs_info' and @compr_type in 'struct ubifs_mount_opts'. 2166 */ 2167 BUILD_BUG_ON(UBIFS_COMPR_TYPES_CNT > 4); 2168 2169 /* 2170 * We require that PAGE_CACHE_SIZE is greater-than-or-equal-to 2171 * UBIFS_BLOCK_SIZE. It is assumed that both are powers of 2. 2172 */ 2173 if (PAGE_CACHE_SIZE < UBIFS_BLOCK_SIZE) { 2174 ubifs_err("VFS page cache size is %u bytes, but UBIFS requires" 2175 " at least 4096 bytes", 2176 (unsigned int)PAGE_CACHE_SIZE); 2177 return -EINVAL; 2178 } 2179 2180 err = register_filesystem(&ubifs_fs_type); 2181 if (err) { 2182 ubifs_err("cannot register file system, error %d", err); 2183 return err; 2184 } 2185 2186 err = -ENOMEM; 2187 ubifs_inode_slab = kmem_cache_create("ubifs_inode_slab", 2188 sizeof(struct ubifs_inode), 0, 2189 SLAB_MEM_SPREAD | SLAB_RECLAIM_ACCOUNT, 2190 &inode_slab_ctor); 2191 if (!ubifs_inode_slab) 2192 goto out_reg; 2193 2194 register_shrinker(&ubifs_shrinker_info); 2195 2196 err = ubifs_compressors_init(); 2197 if (err) 2198 goto out_shrinker; 2199 2200 err = dbg_debugfs_init(); 2201 if (err) 2202 goto out_compr; 2203 2204 return 0; 2205 2206 out_compr: 2207 ubifs_compressors_exit(); 2208 out_shrinker: 2209 unregister_shrinker(&ubifs_shrinker_info); 2210 kmem_cache_destroy(ubifs_inode_slab); 2211 out_reg: 2212 unregister_filesystem(&ubifs_fs_type); 2213 return err; 2214 } 2215 /* late_initcall to let compressors initialize first */ 2216 late_initcall(ubifs_init); 2217 2218 static void __exit ubifs_exit(void) 2219 { 2220 ubifs_assert(list_empty(&ubifs_infos)); 2221 ubifs_assert(atomic_long_read(&ubifs_clean_zn_cnt) == 0); 2222 2223 dbg_debugfs_exit(); 2224 ubifs_compressors_exit(); 2225 unregister_shrinker(&ubifs_shrinker_info); 2226 kmem_cache_destroy(ubifs_inode_slab); 2227 unregister_filesystem(&ubifs_fs_type); 2228 } 2229 module_exit(ubifs_exit); 2230 2231 MODULE_LICENSE("GPL"); 2232 MODULE_VERSION(__stringify(UBIFS_VERSION)); 2233 MODULE_AUTHOR("Artem Bityutskiy, Adrian Hunter"); 2234 MODULE_DESCRIPTION("UBIFS - UBI File System"); 2235