1 /* 2 * super.c - NILFS module and super block management. 3 * 4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 * 20 * Written by Ryusuke Konishi <ryusuke@osrg.net> 21 */ 22 /* 23 * linux/fs/ext2/super.c 24 * 25 * Copyright (C) 1992, 1993, 1994, 1995 26 * Remy Card (card@masi.ibp.fr) 27 * Laboratoire MASI - Institut Blaise Pascal 28 * Universite Pierre et Marie Curie (Paris VI) 29 * 30 * from 31 * 32 * linux/fs/minix/inode.c 33 * 34 * Copyright (C) 1991, 1992 Linus Torvalds 35 * 36 * Big-endian to little-endian byte-swapping/bitmaps by 37 * David S. Miller (davem@caip.rutgers.edu), 1995 38 */ 39 40 #include <linux/module.h> 41 #include <linux/string.h> 42 #include <linux/slab.h> 43 #include <linux/init.h> 44 #include <linux/blkdev.h> 45 #include <linux/parser.h> 46 #include <linux/crc32.h> 47 #include <linux/vfs.h> 48 #include <linux/writeback.h> 49 #include <linux/seq_file.h> 50 #include <linux/mount.h> 51 #include "nilfs.h" 52 #include "export.h" 53 #include "mdt.h" 54 #include "alloc.h" 55 #include "btree.h" 56 #include "btnode.h" 57 #include "page.h" 58 #include "cpfile.h" 59 #include "sufile.h" /* nilfs_sufile_resize(), nilfs_sufile_set_alloc_range() */ 60 #include "ifile.h" 61 #include "dat.h" 62 #include "segment.h" 63 #include "segbuf.h" 64 65 MODULE_AUTHOR("NTT Corp."); 66 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem " 67 "(NILFS)"); 68 MODULE_LICENSE("GPL"); 69 70 static struct kmem_cache *nilfs_inode_cachep; 71 struct kmem_cache *nilfs_transaction_cachep; 72 struct kmem_cache *nilfs_segbuf_cachep; 73 struct kmem_cache *nilfs_btree_path_cache; 74 75 static int nilfs_setup_super(struct super_block *sb, int is_mount); 76 static int nilfs_remount(struct super_block *sb, int *flags, char *data); 77 78 static void nilfs_set_error(struct super_block *sb) 79 { 80 struct the_nilfs *nilfs = sb->s_fs_info; 81 struct nilfs_super_block **sbp; 82 83 down_write(&nilfs->ns_sem); 84 if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) { 85 nilfs->ns_mount_state |= NILFS_ERROR_FS; 86 sbp = nilfs_prepare_super(sb, 0); 87 if (likely(sbp)) { 88 sbp[0]->s_state |= cpu_to_le16(NILFS_ERROR_FS); 89 if (sbp[1]) 90 sbp[1]->s_state |= cpu_to_le16(NILFS_ERROR_FS); 91 nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); 92 } 93 } 94 up_write(&nilfs->ns_sem); 95 } 96 97 /** 98 * nilfs_error() - report failure condition on a filesystem 99 * 100 * nilfs_error() sets an ERROR_FS flag on the superblock as well as 101 * reporting an error message. It should be called when NILFS detects 102 * incoherences or defects of meta data on disk. As for sustainable 103 * errors such as a single-shot I/O error, nilfs_warning() or the printk() 104 * function should be used instead. 105 * 106 * The segment constructor must not call this function because it can 107 * kill itself. 108 */ 109 void nilfs_error(struct super_block *sb, const char *function, 110 const char *fmt, ...) 111 { 112 struct the_nilfs *nilfs = sb->s_fs_info; 113 struct va_format vaf; 114 va_list args; 115 116 va_start(args, fmt); 117 118 vaf.fmt = fmt; 119 vaf.va = &args; 120 121 printk(KERN_CRIT "NILFS error (device %s): %s: %pV\n", 122 sb->s_id, function, &vaf); 123 124 va_end(args); 125 126 if (!(sb->s_flags & MS_RDONLY)) { 127 nilfs_set_error(sb); 128 129 if (nilfs_test_opt(nilfs, ERRORS_RO)) { 130 printk(KERN_CRIT "Remounting filesystem read-only\n"); 131 sb->s_flags |= MS_RDONLY; 132 } 133 } 134 135 if (nilfs_test_opt(nilfs, ERRORS_PANIC)) 136 panic("NILFS (device %s): panic forced after error\n", 137 sb->s_id); 138 } 139 140 void nilfs_warning(struct super_block *sb, const char *function, 141 const char *fmt, ...) 142 { 143 struct va_format vaf; 144 va_list args; 145 146 va_start(args, fmt); 147 148 vaf.fmt = fmt; 149 vaf.va = &args; 150 151 printk(KERN_WARNING "NILFS warning (device %s): %s: %pV\n", 152 sb->s_id, function, &vaf); 153 154 va_end(args); 155 } 156 157 158 struct inode *nilfs_alloc_inode(struct super_block *sb) 159 { 160 struct nilfs_inode_info *ii; 161 162 ii = kmem_cache_alloc(nilfs_inode_cachep, GFP_NOFS); 163 if (!ii) 164 return NULL; 165 ii->i_bh = NULL; 166 ii->i_state = 0; 167 ii->i_cno = 0; 168 ii->vfs_inode.i_version = 1; 169 nilfs_mapping_init(&ii->i_btnode_cache, &ii->vfs_inode); 170 return &ii->vfs_inode; 171 } 172 173 static void nilfs_i_callback(struct rcu_head *head) 174 { 175 struct inode *inode = container_of(head, struct inode, i_rcu); 176 struct nilfs_mdt_info *mdi = NILFS_MDT(inode); 177 178 if (mdi) { 179 kfree(mdi->mi_bgl); /* kfree(NULL) is safe */ 180 kfree(mdi); 181 } 182 kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode)); 183 } 184 185 void nilfs_destroy_inode(struct inode *inode) 186 { 187 call_rcu(&inode->i_rcu, nilfs_i_callback); 188 } 189 190 static int nilfs_sync_super(struct super_block *sb, int flag) 191 { 192 struct the_nilfs *nilfs = sb->s_fs_info; 193 int err; 194 195 retry: 196 set_buffer_dirty(nilfs->ns_sbh[0]); 197 if (nilfs_test_opt(nilfs, BARRIER)) { 198 err = __sync_dirty_buffer(nilfs->ns_sbh[0], 199 WRITE_SYNC | WRITE_FLUSH_FUA); 200 } else { 201 err = sync_dirty_buffer(nilfs->ns_sbh[0]); 202 } 203 204 if (unlikely(err)) { 205 printk(KERN_ERR 206 "NILFS: unable to write superblock (err=%d)\n", err); 207 if (err == -EIO && nilfs->ns_sbh[1]) { 208 /* 209 * sbp[0] points to newer log than sbp[1], 210 * so copy sbp[0] to sbp[1] to take over sbp[0]. 211 */ 212 memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0], 213 nilfs->ns_sbsize); 214 nilfs_fall_back_super_block(nilfs); 215 goto retry; 216 } 217 } else { 218 struct nilfs_super_block *sbp = nilfs->ns_sbp[0]; 219 220 nilfs->ns_sbwcount++; 221 222 /* 223 * The latest segment becomes trailable from the position 224 * written in superblock. 225 */ 226 clear_nilfs_discontinued(nilfs); 227 228 /* update GC protection for recent segments */ 229 if (nilfs->ns_sbh[1]) { 230 if (flag == NILFS_SB_COMMIT_ALL) { 231 set_buffer_dirty(nilfs->ns_sbh[1]); 232 if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0) 233 goto out; 234 } 235 if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) < 236 le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno)) 237 sbp = nilfs->ns_sbp[1]; 238 } 239 240 spin_lock(&nilfs->ns_last_segment_lock); 241 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq); 242 spin_unlock(&nilfs->ns_last_segment_lock); 243 } 244 out: 245 return err; 246 } 247 248 void nilfs_set_log_cursor(struct nilfs_super_block *sbp, 249 struct the_nilfs *nilfs) 250 { 251 sector_t nfreeblocks; 252 253 /* nilfs->ns_sem must be locked by the caller. */ 254 nilfs_count_free_blocks(nilfs, &nfreeblocks); 255 sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks); 256 257 spin_lock(&nilfs->ns_last_segment_lock); 258 sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq); 259 sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg); 260 sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno); 261 spin_unlock(&nilfs->ns_last_segment_lock); 262 } 263 264 struct nilfs_super_block **nilfs_prepare_super(struct super_block *sb, 265 int flip) 266 { 267 struct the_nilfs *nilfs = sb->s_fs_info; 268 struct nilfs_super_block **sbp = nilfs->ns_sbp; 269 270 /* nilfs->ns_sem must be locked by the caller. */ 271 if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) { 272 if (sbp[1] && 273 sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) { 274 memcpy(sbp[0], sbp[1], nilfs->ns_sbsize); 275 } else { 276 printk(KERN_CRIT "NILFS: superblock broke on dev %s\n", 277 sb->s_id); 278 return NULL; 279 } 280 } else if (sbp[1] && 281 sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) { 282 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); 283 } 284 285 if (flip && sbp[1]) 286 nilfs_swap_super_block(nilfs); 287 288 return sbp; 289 } 290 291 int nilfs_commit_super(struct super_block *sb, int flag) 292 { 293 struct the_nilfs *nilfs = sb->s_fs_info; 294 struct nilfs_super_block **sbp = nilfs->ns_sbp; 295 time_t t; 296 297 /* nilfs->ns_sem must be locked by the caller. */ 298 t = get_seconds(); 299 nilfs->ns_sbwtime = t; 300 sbp[0]->s_wtime = cpu_to_le64(t); 301 sbp[0]->s_sum = 0; 302 sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed, 303 (unsigned char *)sbp[0], 304 nilfs->ns_sbsize)); 305 if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) { 306 sbp[1]->s_wtime = sbp[0]->s_wtime; 307 sbp[1]->s_sum = 0; 308 sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed, 309 (unsigned char *)sbp[1], 310 nilfs->ns_sbsize)); 311 } 312 clear_nilfs_sb_dirty(nilfs); 313 nilfs->ns_flushed_device = 1; 314 /* make sure store to ns_flushed_device cannot be reordered */ 315 smp_wmb(); 316 return nilfs_sync_super(sb, flag); 317 } 318 319 /** 320 * nilfs_cleanup_super() - write filesystem state for cleanup 321 * @sb: super block instance to be unmounted or degraded to read-only 322 * 323 * This function restores state flags in the on-disk super block. 324 * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the 325 * filesystem was not clean previously. 326 */ 327 int nilfs_cleanup_super(struct super_block *sb) 328 { 329 struct the_nilfs *nilfs = sb->s_fs_info; 330 struct nilfs_super_block **sbp; 331 int flag = NILFS_SB_COMMIT; 332 int ret = -EIO; 333 334 sbp = nilfs_prepare_super(sb, 0); 335 if (sbp) { 336 sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state); 337 nilfs_set_log_cursor(sbp[0], nilfs); 338 if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) { 339 /* 340 * make the "clean" flag also to the opposite 341 * super block if both super blocks point to 342 * the same checkpoint. 343 */ 344 sbp[1]->s_state = sbp[0]->s_state; 345 flag = NILFS_SB_COMMIT_ALL; 346 } 347 ret = nilfs_commit_super(sb, flag); 348 } 349 return ret; 350 } 351 352 /** 353 * nilfs_move_2nd_super - relocate secondary super block 354 * @sb: super block instance 355 * @sb2off: new offset of the secondary super block (in bytes) 356 */ 357 static int nilfs_move_2nd_super(struct super_block *sb, loff_t sb2off) 358 { 359 struct the_nilfs *nilfs = sb->s_fs_info; 360 struct buffer_head *nsbh; 361 struct nilfs_super_block *nsbp; 362 sector_t blocknr, newblocknr; 363 unsigned long offset; 364 int sb2i; /* array index of the secondary superblock */ 365 int ret = 0; 366 367 /* nilfs->ns_sem must be locked by the caller. */ 368 if (nilfs->ns_sbh[1] && 369 nilfs->ns_sbh[1]->b_blocknr > nilfs->ns_first_data_block) { 370 sb2i = 1; 371 blocknr = nilfs->ns_sbh[1]->b_blocknr; 372 } else if (nilfs->ns_sbh[0]->b_blocknr > nilfs->ns_first_data_block) { 373 sb2i = 0; 374 blocknr = nilfs->ns_sbh[0]->b_blocknr; 375 } else { 376 sb2i = -1; 377 blocknr = 0; 378 } 379 if (sb2i >= 0 && (u64)blocknr << nilfs->ns_blocksize_bits == sb2off) 380 goto out; /* super block location is unchanged */ 381 382 /* Get new super block buffer */ 383 newblocknr = sb2off >> nilfs->ns_blocksize_bits; 384 offset = sb2off & (nilfs->ns_blocksize - 1); 385 nsbh = sb_getblk(sb, newblocknr); 386 if (!nsbh) { 387 printk(KERN_WARNING 388 "NILFS warning: unable to move secondary superblock " 389 "to block %llu\n", (unsigned long long)newblocknr); 390 ret = -EIO; 391 goto out; 392 } 393 nsbp = (void *)nsbh->b_data + offset; 394 memset(nsbp, 0, nilfs->ns_blocksize); 395 396 if (sb2i >= 0) { 397 memcpy(nsbp, nilfs->ns_sbp[sb2i], nilfs->ns_sbsize); 398 brelse(nilfs->ns_sbh[sb2i]); 399 nilfs->ns_sbh[sb2i] = nsbh; 400 nilfs->ns_sbp[sb2i] = nsbp; 401 } else if (nilfs->ns_sbh[0]->b_blocknr < nilfs->ns_first_data_block) { 402 /* secondary super block will be restored to index 1 */ 403 nilfs->ns_sbh[1] = nsbh; 404 nilfs->ns_sbp[1] = nsbp; 405 } else { 406 brelse(nsbh); 407 } 408 out: 409 return ret; 410 } 411 412 /** 413 * nilfs_resize_fs - resize the filesystem 414 * @sb: super block instance 415 * @newsize: new size of the filesystem (in bytes) 416 */ 417 int nilfs_resize_fs(struct super_block *sb, __u64 newsize) 418 { 419 struct the_nilfs *nilfs = sb->s_fs_info; 420 struct nilfs_super_block **sbp; 421 __u64 devsize, newnsegs; 422 loff_t sb2off; 423 int ret; 424 425 ret = -ERANGE; 426 devsize = i_size_read(sb->s_bdev->bd_inode); 427 if (newsize > devsize) 428 goto out; 429 430 /* 431 * Write lock is required to protect some functions depending 432 * on the number of segments, the number of reserved segments, 433 * and so forth. 434 */ 435 down_write(&nilfs->ns_segctor_sem); 436 437 sb2off = NILFS_SB2_OFFSET_BYTES(newsize); 438 newnsegs = sb2off >> nilfs->ns_blocksize_bits; 439 do_div(newnsegs, nilfs->ns_blocks_per_segment); 440 441 ret = nilfs_sufile_resize(nilfs->ns_sufile, newnsegs); 442 up_write(&nilfs->ns_segctor_sem); 443 if (ret < 0) 444 goto out; 445 446 ret = nilfs_construct_segment(sb); 447 if (ret < 0) 448 goto out; 449 450 down_write(&nilfs->ns_sem); 451 nilfs_move_2nd_super(sb, sb2off); 452 ret = -EIO; 453 sbp = nilfs_prepare_super(sb, 0); 454 if (likely(sbp)) { 455 nilfs_set_log_cursor(sbp[0], nilfs); 456 /* 457 * Drop NILFS_RESIZE_FS flag for compatibility with 458 * mount-time resize which may be implemented in a 459 * future release. 460 */ 461 sbp[0]->s_state = cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & 462 ~NILFS_RESIZE_FS); 463 sbp[0]->s_dev_size = cpu_to_le64(newsize); 464 sbp[0]->s_nsegments = cpu_to_le64(nilfs->ns_nsegments); 465 if (sbp[1]) 466 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); 467 ret = nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); 468 } 469 up_write(&nilfs->ns_sem); 470 471 /* 472 * Reset the range of allocatable segments last. This order 473 * is important in the case of expansion because the secondary 474 * superblock must be protected from log write until migration 475 * completes. 476 */ 477 if (!ret) 478 nilfs_sufile_set_alloc_range(nilfs->ns_sufile, 0, newnsegs - 1); 479 out: 480 return ret; 481 } 482 483 static void nilfs_put_super(struct super_block *sb) 484 { 485 struct the_nilfs *nilfs = sb->s_fs_info; 486 487 nilfs_detach_log_writer(sb); 488 489 if (!(sb->s_flags & MS_RDONLY)) { 490 down_write(&nilfs->ns_sem); 491 nilfs_cleanup_super(sb); 492 up_write(&nilfs->ns_sem); 493 } 494 495 iput(nilfs->ns_sufile); 496 iput(nilfs->ns_cpfile); 497 iput(nilfs->ns_dat); 498 499 destroy_nilfs(nilfs); 500 sb->s_fs_info = NULL; 501 } 502 503 static int nilfs_sync_fs(struct super_block *sb, int wait) 504 { 505 struct the_nilfs *nilfs = sb->s_fs_info; 506 struct nilfs_super_block **sbp; 507 int err = 0; 508 509 /* This function is called when super block should be written back */ 510 if (wait) 511 err = nilfs_construct_segment(sb); 512 513 down_write(&nilfs->ns_sem); 514 if (nilfs_sb_dirty(nilfs)) { 515 sbp = nilfs_prepare_super(sb, nilfs_sb_will_flip(nilfs)); 516 if (likely(sbp)) { 517 nilfs_set_log_cursor(sbp[0], nilfs); 518 nilfs_commit_super(sb, NILFS_SB_COMMIT); 519 } 520 } 521 up_write(&nilfs->ns_sem); 522 523 if (!err) 524 err = nilfs_flush_device(nilfs); 525 526 return err; 527 } 528 529 int nilfs_attach_checkpoint(struct super_block *sb, __u64 cno, int curr_mnt, 530 struct nilfs_root **rootp) 531 { 532 struct the_nilfs *nilfs = sb->s_fs_info; 533 struct nilfs_root *root; 534 struct nilfs_checkpoint *raw_cp; 535 struct buffer_head *bh_cp; 536 int err = -ENOMEM; 537 538 root = nilfs_find_or_create_root( 539 nilfs, curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno); 540 if (!root) 541 return err; 542 543 if (root->ifile) 544 goto reuse; /* already attached checkpoint */ 545 546 down_read(&nilfs->ns_segctor_sem); 547 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp, 548 &bh_cp); 549 up_read(&nilfs->ns_segctor_sem); 550 if (unlikely(err)) { 551 if (err == -ENOENT || err == -EINVAL) { 552 printk(KERN_ERR 553 "NILFS: Invalid checkpoint " 554 "(checkpoint number=%llu)\n", 555 (unsigned long long)cno); 556 err = -EINVAL; 557 } 558 goto failed; 559 } 560 561 err = nilfs_ifile_read(sb, root, nilfs->ns_inode_size, 562 &raw_cp->cp_ifile_inode, &root->ifile); 563 if (err) 564 goto failed_bh; 565 566 atomic64_set(&root->inodes_count, 567 le64_to_cpu(raw_cp->cp_inodes_count)); 568 atomic64_set(&root->blocks_count, 569 le64_to_cpu(raw_cp->cp_blocks_count)); 570 571 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp); 572 573 reuse: 574 *rootp = root; 575 return 0; 576 577 failed_bh: 578 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp); 579 failed: 580 nilfs_put_root(root); 581 582 return err; 583 } 584 585 static int nilfs_freeze(struct super_block *sb) 586 { 587 struct the_nilfs *nilfs = sb->s_fs_info; 588 int err; 589 590 if (sb->s_flags & MS_RDONLY) 591 return 0; 592 593 /* Mark super block clean */ 594 down_write(&nilfs->ns_sem); 595 err = nilfs_cleanup_super(sb); 596 up_write(&nilfs->ns_sem); 597 return err; 598 } 599 600 static int nilfs_unfreeze(struct super_block *sb) 601 { 602 struct the_nilfs *nilfs = sb->s_fs_info; 603 604 if (sb->s_flags & MS_RDONLY) 605 return 0; 606 607 down_write(&nilfs->ns_sem); 608 nilfs_setup_super(sb, false); 609 up_write(&nilfs->ns_sem); 610 return 0; 611 } 612 613 static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf) 614 { 615 struct super_block *sb = dentry->d_sb; 616 struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root; 617 struct the_nilfs *nilfs = root->nilfs; 618 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 619 unsigned long long blocks; 620 unsigned long overhead; 621 unsigned long nrsvblocks; 622 sector_t nfreeblocks; 623 u64 nmaxinodes, nfreeinodes; 624 int err; 625 626 /* 627 * Compute all of the segment blocks 628 * 629 * The blocks before first segment and after last segment 630 * are excluded. 631 */ 632 blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments 633 - nilfs->ns_first_data_block; 634 nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment; 635 636 /* 637 * Compute the overhead 638 * 639 * When distributing meta data blocks outside segment structure, 640 * We must count them as the overhead. 641 */ 642 overhead = 0; 643 644 err = nilfs_count_free_blocks(nilfs, &nfreeblocks); 645 if (unlikely(err)) 646 return err; 647 648 err = nilfs_ifile_count_free_inodes(root->ifile, 649 &nmaxinodes, &nfreeinodes); 650 if (unlikely(err)) { 651 printk(KERN_WARNING 652 "NILFS warning: fail to count free inodes: err %d.\n", 653 err); 654 if (err == -ERANGE) { 655 /* 656 * If nilfs_palloc_count_max_entries() returns 657 * -ERANGE error code then we simply treat 658 * curent inodes count as maximum possible and 659 * zero as free inodes value. 660 */ 661 nmaxinodes = atomic64_read(&root->inodes_count); 662 nfreeinodes = 0; 663 err = 0; 664 } else 665 return err; 666 } 667 668 buf->f_type = NILFS_SUPER_MAGIC; 669 buf->f_bsize = sb->s_blocksize; 670 buf->f_blocks = blocks - overhead; 671 buf->f_bfree = nfreeblocks; 672 buf->f_bavail = (buf->f_bfree >= nrsvblocks) ? 673 (buf->f_bfree - nrsvblocks) : 0; 674 buf->f_files = nmaxinodes; 675 buf->f_ffree = nfreeinodes; 676 buf->f_namelen = NILFS_NAME_LEN; 677 buf->f_fsid.val[0] = (u32)id; 678 buf->f_fsid.val[1] = (u32)(id >> 32); 679 680 return 0; 681 } 682 683 static int nilfs_show_options(struct seq_file *seq, struct dentry *dentry) 684 { 685 struct super_block *sb = dentry->d_sb; 686 struct the_nilfs *nilfs = sb->s_fs_info; 687 struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root; 688 689 if (!nilfs_test_opt(nilfs, BARRIER)) 690 seq_puts(seq, ",nobarrier"); 691 if (root->cno != NILFS_CPTREE_CURRENT_CNO) 692 seq_printf(seq, ",cp=%llu", (unsigned long long)root->cno); 693 if (nilfs_test_opt(nilfs, ERRORS_PANIC)) 694 seq_puts(seq, ",errors=panic"); 695 if (nilfs_test_opt(nilfs, ERRORS_CONT)) 696 seq_puts(seq, ",errors=continue"); 697 if (nilfs_test_opt(nilfs, STRICT_ORDER)) 698 seq_puts(seq, ",order=strict"); 699 if (nilfs_test_opt(nilfs, NORECOVERY)) 700 seq_puts(seq, ",norecovery"); 701 if (nilfs_test_opt(nilfs, DISCARD)) 702 seq_puts(seq, ",discard"); 703 704 return 0; 705 } 706 707 static const struct super_operations nilfs_sops = { 708 .alloc_inode = nilfs_alloc_inode, 709 .destroy_inode = nilfs_destroy_inode, 710 .dirty_inode = nilfs_dirty_inode, 711 .evict_inode = nilfs_evict_inode, 712 .put_super = nilfs_put_super, 713 .sync_fs = nilfs_sync_fs, 714 .freeze_fs = nilfs_freeze, 715 .unfreeze_fs = nilfs_unfreeze, 716 .statfs = nilfs_statfs, 717 .remount_fs = nilfs_remount, 718 .show_options = nilfs_show_options 719 }; 720 721 enum { 722 Opt_err_cont, Opt_err_panic, Opt_err_ro, 723 Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery, 724 Opt_discard, Opt_nodiscard, Opt_err, 725 }; 726 727 static match_table_t tokens = { 728 {Opt_err_cont, "errors=continue"}, 729 {Opt_err_panic, "errors=panic"}, 730 {Opt_err_ro, "errors=remount-ro"}, 731 {Opt_barrier, "barrier"}, 732 {Opt_nobarrier, "nobarrier"}, 733 {Opt_snapshot, "cp=%u"}, 734 {Opt_order, "order=%s"}, 735 {Opt_norecovery, "norecovery"}, 736 {Opt_discard, "discard"}, 737 {Opt_nodiscard, "nodiscard"}, 738 {Opt_err, NULL} 739 }; 740 741 static int parse_options(char *options, struct super_block *sb, int is_remount) 742 { 743 struct the_nilfs *nilfs = sb->s_fs_info; 744 char *p; 745 substring_t args[MAX_OPT_ARGS]; 746 747 if (!options) 748 return 1; 749 750 while ((p = strsep(&options, ",")) != NULL) { 751 int token; 752 if (!*p) 753 continue; 754 755 token = match_token(p, tokens, args); 756 switch (token) { 757 case Opt_barrier: 758 nilfs_set_opt(nilfs, BARRIER); 759 break; 760 case Opt_nobarrier: 761 nilfs_clear_opt(nilfs, BARRIER); 762 break; 763 case Opt_order: 764 if (strcmp(args[0].from, "relaxed") == 0) 765 /* Ordered data semantics */ 766 nilfs_clear_opt(nilfs, STRICT_ORDER); 767 else if (strcmp(args[0].from, "strict") == 0) 768 /* Strict in-order semantics */ 769 nilfs_set_opt(nilfs, STRICT_ORDER); 770 else 771 return 0; 772 break; 773 case Opt_err_panic: 774 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_PANIC); 775 break; 776 case Opt_err_ro: 777 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_RO); 778 break; 779 case Opt_err_cont: 780 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_CONT); 781 break; 782 case Opt_snapshot: 783 if (is_remount) { 784 printk(KERN_ERR 785 "NILFS: \"%s\" option is invalid " 786 "for remount.\n", p); 787 return 0; 788 } 789 break; 790 case Opt_norecovery: 791 nilfs_set_opt(nilfs, NORECOVERY); 792 break; 793 case Opt_discard: 794 nilfs_set_opt(nilfs, DISCARD); 795 break; 796 case Opt_nodiscard: 797 nilfs_clear_opt(nilfs, DISCARD); 798 break; 799 default: 800 printk(KERN_ERR 801 "NILFS: Unrecognized mount option \"%s\"\n", p); 802 return 0; 803 } 804 } 805 return 1; 806 } 807 808 static inline void 809 nilfs_set_default_options(struct super_block *sb, 810 struct nilfs_super_block *sbp) 811 { 812 struct the_nilfs *nilfs = sb->s_fs_info; 813 814 nilfs->ns_mount_opt = 815 NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER; 816 } 817 818 static int nilfs_setup_super(struct super_block *sb, int is_mount) 819 { 820 struct the_nilfs *nilfs = sb->s_fs_info; 821 struct nilfs_super_block **sbp; 822 int max_mnt_count; 823 int mnt_count; 824 825 /* nilfs->ns_sem must be locked by the caller. */ 826 sbp = nilfs_prepare_super(sb, 0); 827 if (!sbp) 828 return -EIO; 829 830 if (!is_mount) 831 goto skip_mount_setup; 832 833 max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count); 834 mnt_count = le16_to_cpu(sbp[0]->s_mnt_count); 835 836 if (nilfs->ns_mount_state & NILFS_ERROR_FS) { 837 printk(KERN_WARNING 838 "NILFS warning: mounting fs with errors\n"); 839 #if 0 840 } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) { 841 printk(KERN_WARNING 842 "NILFS warning: maximal mount count reached\n"); 843 #endif 844 } 845 if (!max_mnt_count) 846 sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT); 847 848 sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1); 849 sbp[0]->s_mtime = cpu_to_le64(get_seconds()); 850 851 skip_mount_setup: 852 sbp[0]->s_state = 853 cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS); 854 /* synchronize sbp[1] with sbp[0] */ 855 if (sbp[1]) 856 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); 857 return nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); 858 } 859 860 struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb, 861 u64 pos, int blocksize, 862 struct buffer_head **pbh) 863 { 864 unsigned long long sb_index = pos; 865 unsigned long offset; 866 867 offset = do_div(sb_index, blocksize); 868 *pbh = sb_bread(sb, sb_index); 869 if (!*pbh) 870 return NULL; 871 return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset); 872 } 873 874 int nilfs_store_magic_and_option(struct super_block *sb, 875 struct nilfs_super_block *sbp, 876 char *data) 877 { 878 struct the_nilfs *nilfs = sb->s_fs_info; 879 880 sb->s_magic = le16_to_cpu(sbp->s_magic); 881 882 /* FS independent flags */ 883 #ifdef NILFS_ATIME_DISABLE 884 sb->s_flags |= MS_NOATIME; 885 #endif 886 887 nilfs_set_default_options(sb, sbp); 888 889 nilfs->ns_resuid = le16_to_cpu(sbp->s_def_resuid); 890 nilfs->ns_resgid = le16_to_cpu(sbp->s_def_resgid); 891 nilfs->ns_interval = le32_to_cpu(sbp->s_c_interval); 892 nilfs->ns_watermark = le32_to_cpu(sbp->s_c_block_max); 893 894 return !parse_options(data, sb, 0) ? -EINVAL : 0 ; 895 } 896 897 int nilfs_check_feature_compatibility(struct super_block *sb, 898 struct nilfs_super_block *sbp) 899 { 900 __u64 features; 901 902 features = le64_to_cpu(sbp->s_feature_incompat) & 903 ~NILFS_FEATURE_INCOMPAT_SUPP; 904 if (features) { 905 printk(KERN_ERR "NILFS: couldn't mount because of unsupported " 906 "optional features (%llx)\n", 907 (unsigned long long)features); 908 return -EINVAL; 909 } 910 features = le64_to_cpu(sbp->s_feature_compat_ro) & 911 ~NILFS_FEATURE_COMPAT_RO_SUPP; 912 if (!(sb->s_flags & MS_RDONLY) && features) { 913 printk(KERN_ERR "NILFS: couldn't mount RDWR because of " 914 "unsupported optional features (%llx)\n", 915 (unsigned long long)features); 916 return -EINVAL; 917 } 918 return 0; 919 } 920 921 static int nilfs_get_root_dentry(struct super_block *sb, 922 struct nilfs_root *root, 923 struct dentry **root_dentry) 924 { 925 struct inode *inode; 926 struct dentry *dentry; 927 int ret = 0; 928 929 inode = nilfs_iget(sb, root, NILFS_ROOT_INO); 930 if (IS_ERR(inode)) { 931 printk(KERN_ERR "NILFS: get root inode failed\n"); 932 ret = PTR_ERR(inode); 933 goto out; 934 } 935 if (!S_ISDIR(inode->i_mode) || !inode->i_blocks || !inode->i_size) { 936 iput(inode); 937 printk(KERN_ERR "NILFS: corrupt root inode.\n"); 938 ret = -EINVAL; 939 goto out; 940 } 941 942 if (root->cno == NILFS_CPTREE_CURRENT_CNO) { 943 dentry = d_find_alias(inode); 944 if (!dentry) { 945 dentry = d_make_root(inode); 946 if (!dentry) { 947 ret = -ENOMEM; 948 goto failed_dentry; 949 } 950 } else { 951 iput(inode); 952 } 953 } else { 954 dentry = d_obtain_root(inode); 955 if (IS_ERR(dentry)) { 956 ret = PTR_ERR(dentry); 957 goto failed_dentry; 958 } 959 } 960 *root_dentry = dentry; 961 out: 962 return ret; 963 964 failed_dentry: 965 printk(KERN_ERR "NILFS: get root dentry failed\n"); 966 goto out; 967 } 968 969 static int nilfs_attach_snapshot(struct super_block *s, __u64 cno, 970 struct dentry **root_dentry) 971 { 972 struct the_nilfs *nilfs = s->s_fs_info; 973 struct nilfs_root *root; 974 int ret; 975 976 mutex_lock(&nilfs->ns_snapshot_mount_mutex); 977 978 down_read(&nilfs->ns_segctor_sem); 979 ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno); 980 up_read(&nilfs->ns_segctor_sem); 981 if (ret < 0) { 982 ret = (ret == -ENOENT) ? -EINVAL : ret; 983 goto out; 984 } else if (!ret) { 985 printk(KERN_ERR "NILFS: The specified checkpoint is " 986 "not a snapshot (checkpoint number=%llu).\n", 987 (unsigned long long)cno); 988 ret = -EINVAL; 989 goto out; 990 } 991 992 ret = nilfs_attach_checkpoint(s, cno, false, &root); 993 if (ret) { 994 printk(KERN_ERR "NILFS: error loading snapshot " 995 "(checkpoint number=%llu).\n", 996 (unsigned long long)cno); 997 goto out; 998 } 999 ret = nilfs_get_root_dentry(s, root, root_dentry); 1000 nilfs_put_root(root); 1001 out: 1002 mutex_unlock(&nilfs->ns_snapshot_mount_mutex); 1003 return ret; 1004 } 1005 1006 /** 1007 * nilfs_tree_is_busy() - try to shrink dentries of a checkpoint 1008 * @root_dentry: root dentry of the tree to be shrunk 1009 * 1010 * This function returns true if the tree was in-use. 1011 */ 1012 static bool nilfs_tree_is_busy(struct dentry *root_dentry) 1013 { 1014 shrink_dcache_parent(root_dentry); 1015 return d_count(root_dentry) > 1; 1016 } 1017 1018 int nilfs_checkpoint_is_mounted(struct super_block *sb, __u64 cno) 1019 { 1020 struct the_nilfs *nilfs = sb->s_fs_info; 1021 struct nilfs_root *root; 1022 struct inode *inode; 1023 struct dentry *dentry; 1024 int ret; 1025 1026 if (cno > nilfs->ns_cno) 1027 return false; 1028 1029 if (cno >= nilfs_last_cno(nilfs)) 1030 return true; /* protect recent checkpoints */ 1031 1032 ret = false; 1033 root = nilfs_lookup_root(nilfs, cno); 1034 if (root) { 1035 inode = nilfs_ilookup(sb, root, NILFS_ROOT_INO); 1036 if (inode) { 1037 dentry = d_find_alias(inode); 1038 if (dentry) { 1039 ret = nilfs_tree_is_busy(dentry); 1040 dput(dentry); 1041 } 1042 iput(inode); 1043 } 1044 nilfs_put_root(root); 1045 } 1046 return ret; 1047 } 1048 1049 /** 1050 * nilfs_fill_super() - initialize a super block instance 1051 * @sb: super_block 1052 * @data: mount options 1053 * @silent: silent mode flag 1054 * 1055 * This function is called exclusively by nilfs->ns_mount_mutex. 1056 * So, the recovery process is protected from other simultaneous mounts. 1057 */ 1058 static int 1059 nilfs_fill_super(struct super_block *sb, void *data, int silent) 1060 { 1061 struct the_nilfs *nilfs; 1062 struct nilfs_root *fsroot; 1063 __u64 cno; 1064 int err; 1065 1066 nilfs = alloc_nilfs(sb->s_bdev); 1067 if (!nilfs) 1068 return -ENOMEM; 1069 1070 sb->s_fs_info = nilfs; 1071 1072 err = init_nilfs(nilfs, sb, (char *)data); 1073 if (err) 1074 goto failed_nilfs; 1075 1076 sb->s_op = &nilfs_sops; 1077 sb->s_export_op = &nilfs_export_ops; 1078 sb->s_root = NULL; 1079 sb->s_time_gran = 1; 1080 sb->s_max_links = NILFS_LINK_MAX; 1081 1082 sb->s_bdi = &bdev_get_queue(sb->s_bdev)->backing_dev_info; 1083 1084 err = load_nilfs(nilfs, sb); 1085 if (err) 1086 goto failed_nilfs; 1087 1088 cno = nilfs_last_cno(nilfs); 1089 err = nilfs_attach_checkpoint(sb, cno, true, &fsroot); 1090 if (err) { 1091 printk(KERN_ERR "NILFS: error loading last checkpoint " 1092 "(checkpoint number=%llu).\n", (unsigned long long)cno); 1093 goto failed_unload; 1094 } 1095 1096 if (!(sb->s_flags & MS_RDONLY)) { 1097 err = nilfs_attach_log_writer(sb, fsroot); 1098 if (err) 1099 goto failed_checkpoint; 1100 } 1101 1102 err = nilfs_get_root_dentry(sb, fsroot, &sb->s_root); 1103 if (err) 1104 goto failed_segctor; 1105 1106 nilfs_put_root(fsroot); 1107 1108 if (!(sb->s_flags & MS_RDONLY)) { 1109 down_write(&nilfs->ns_sem); 1110 nilfs_setup_super(sb, true); 1111 up_write(&nilfs->ns_sem); 1112 } 1113 1114 return 0; 1115 1116 failed_segctor: 1117 nilfs_detach_log_writer(sb); 1118 1119 failed_checkpoint: 1120 nilfs_put_root(fsroot); 1121 1122 failed_unload: 1123 iput(nilfs->ns_sufile); 1124 iput(nilfs->ns_cpfile); 1125 iput(nilfs->ns_dat); 1126 1127 failed_nilfs: 1128 destroy_nilfs(nilfs); 1129 return err; 1130 } 1131 1132 static int nilfs_remount(struct super_block *sb, int *flags, char *data) 1133 { 1134 struct the_nilfs *nilfs = sb->s_fs_info; 1135 unsigned long old_sb_flags; 1136 unsigned long old_mount_opt; 1137 int err; 1138 1139 sync_filesystem(sb); 1140 old_sb_flags = sb->s_flags; 1141 old_mount_opt = nilfs->ns_mount_opt; 1142 1143 if (!parse_options(data, sb, 1)) { 1144 err = -EINVAL; 1145 goto restore_opts; 1146 } 1147 sb->s_flags = (sb->s_flags & ~MS_POSIXACL); 1148 1149 err = -EINVAL; 1150 1151 if (!nilfs_valid_fs(nilfs)) { 1152 printk(KERN_WARNING "NILFS (device %s): couldn't " 1153 "remount because the filesystem is in an " 1154 "incomplete recovery state.\n", sb->s_id); 1155 goto restore_opts; 1156 } 1157 1158 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 1159 goto out; 1160 if (*flags & MS_RDONLY) { 1161 /* Shutting down log writer */ 1162 nilfs_detach_log_writer(sb); 1163 sb->s_flags |= MS_RDONLY; 1164 1165 /* 1166 * Remounting a valid RW partition RDONLY, so set 1167 * the RDONLY flag and then mark the partition as valid again. 1168 */ 1169 down_write(&nilfs->ns_sem); 1170 nilfs_cleanup_super(sb); 1171 up_write(&nilfs->ns_sem); 1172 } else { 1173 __u64 features; 1174 struct nilfs_root *root; 1175 1176 /* 1177 * Mounting a RDONLY partition read-write, so reread and 1178 * store the current valid flag. (It may have been changed 1179 * by fsck since we originally mounted the partition.) 1180 */ 1181 down_read(&nilfs->ns_sem); 1182 features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) & 1183 ~NILFS_FEATURE_COMPAT_RO_SUPP; 1184 up_read(&nilfs->ns_sem); 1185 if (features) { 1186 printk(KERN_WARNING "NILFS (device %s): couldn't " 1187 "remount RDWR because of unsupported optional " 1188 "features (%llx)\n", 1189 sb->s_id, (unsigned long long)features); 1190 err = -EROFS; 1191 goto restore_opts; 1192 } 1193 1194 sb->s_flags &= ~MS_RDONLY; 1195 1196 root = NILFS_I(d_inode(sb->s_root))->i_root; 1197 err = nilfs_attach_log_writer(sb, root); 1198 if (err) 1199 goto restore_opts; 1200 1201 down_write(&nilfs->ns_sem); 1202 nilfs_setup_super(sb, true); 1203 up_write(&nilfs->ns_sem); 1204 } 1205 out: 1206 return 0; 1207 1208 restore_opts: 1209 sb->s_flags = old_sb_flags; 1210 nilfs->ns_mount_opt = old_mount_opt; 1211 return err; 1212 } 1213 1214 struct nilfs_super_data { 1215 struct block_device *bdev; 1216 __u64 cno; 1217 int flags; 1218 }; 1219 1220 /** 1221 * nilfs_identify - pre-read mount options needed to identify mount instance 1222 * @data: mount options 1223 * @sd: nilfs_super_data 1224 */ 1225 static int nilfs_identify(char *data, struct nilfs_super_data *sd) 1226 { 1227 char *p, *options = data; 1228 substring_t args[MAX_OPT_ARGS]; 1229 int token; 1230 int ret = 0; 1231 1232 do { 1233 p = strsep(&options, ","); 1234 if (p != NULL && *p) { 1235 token = match_token(p, tokens, args); 1236 if (token == Opt_snapshot) { 1237 if (!(sd->flags & MS_RDONLY)) { 1238 ret++; 1239 } else { 1240 sd->cno = simple_strtoull(args[0].from, 1241 NULL, 0); 1242 /* 1243 * No need to see the end pointer; 1244 * match_token() has done syntax 1245 * checking. 1246 */ 1247 if (sd->cno == 0) 1248 ret++; 1249 } 1250 } 1251 if (ret) 1252 printk(KERN_ERR 1253 "NILFS: invalid mount option: %s\n", p); 1254 } 1255 if (!options) 1256 break; 1257 BUG_ON(options == data); 1258 *(options - 1) = ','; 1259 } while (!ret); 1260 return ret; 1261 } 1262 1263 static int nilfs_set_bdev_super(struct super_block *s, void *data) 1264 { 1265 s->s_bdev = data; 1266 s->s_dev = s->s_bdev->bd_dev; 1267 return 0; 1268 } 1269 1270 static int nilfs_test_bdev_super(struct super_block *s, void *data) 1271 { 1272 return (void *)s->s_bdev == data; 1273 } 1274 1275 static struct dentry * 1276 nilfs_mount(struct file_system_type *fs_type, int flags, 1277 const char *dev_name, void *data) 1278 { 1279 struct nilfs_super_data sd; 1280 struct super_block *s; 1281 fmode_t mode = FMODE_READ | FMODE_EXCL; 1282 struct dentry *root_dentry; 1283 int err, s_new = false; 1284 1285 if (!(flags & MS_RDONLY)) 1286 mode |= FMODE_WRITE; 1287 1288 sd.bdev = blkdev_get_by_path(dev_name, mode, fs_type); 1289 if (IS_ERR(sd.bdev)) 1290 return ERR_CAST(sd.bdev); 1291 1292 sd.cno = 0; 1293 sd.flags = flags; 1294 if (nilfs_identify((char *)data, &sd)) { 1295 err = -EINVAL; 1296 goto failed; 1297 } 1298 1299 /* 1300 * once the super is inserted into the list by sget, s_umount 1301 * will protect the lockfs code from trying to start a snapshot 1302 * while we are mounting 1303 */ 1304 mutex_lock(&sd.bdev->bd_fsfreeze_mutex); 1305 if (sd.bdev->bd_fsfreeze_count > 0) { 1306 mutex_unlock(&sd.bdev->bd_fsfreeze_mutex); 1307 err = -EBUSY; 1308 goto failed; 1309 } 1310 s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, flags, 1311 sd.bdev); 1312 mutex_unlock(&sd.bdev->bd_fsfreeze_mutex); 1313 if (IS_ERR(s)) { 1314 err = PTR_ERR(s); 1315 goto failed; 1316 } 1317 1318 if (!s->s_root) { 1319 s_new = true; 1320 1321 /* New superblock instance created */ 1322 s->s_mode = mode; 1323 snprintf(s->s_id, sizeof(s->s_id), "%pg", sd.bdev); 1324 sb_set_blocksize(s, block_size(sd.bdev)); 1325 1326 err = nilfs_fill_super(s, data, flags & MS_SILENT ? 1 : 0); 1327 if (err) 1328 goto failed_super; 1329 1330 s->s_flags |= MS_ACTIVE; 1331 } else if (!sd.cno) { 1332 if (nilfs_tree_is_busy(s->s_root)) { 1333 if ((flags ^ s->s_flags) & MS_RDONLY) { 1334 printk(KERN_ERR "NILFS: the device already " 1335 "has a %s mount.\n", 1336 (s->s_flags & MS_RDONLY) ? 1337 "read-only" : "read/write"); 1338 err = -EBUSY; 1339 goto failed_super; 1340 } 1341 } else { 1342 /* 1343 * Try remount to setup mount states if the current 1344 * tree is not mounted and only snapshots use this sb. 1345 */ 1346 err = nilfs_remount(s, &flags, data); 1347 if (err) 1348 goto failed_super; 1349 } 1350 } 1351 1352 if (sd.cno) { 1353 err = nilfs_attach_snapshot(s, sd.cno, &root_dentry); 1354 if (err) 1355 goto failed_super; 1356 } else { 1357 root_dentry = dget(s->s_root); 1358 } 1359 1360 if (!s_new) 1361 blkdev_put(sd.bdev, mode); 1362 1363 return root_dentry; 1364 1365 failed_super: 1366 deactivate_locked_super(s); 1367 1368 failed: 1369 if (!s_new) 1370 blkdev_put(sd.bdev, mode); 1371 return ERR_PTR(err); 1372 } 1373 1374 struct file_system_type nilfs_fs_type = { 1375 .owner = THIS_MODULE, 1376 .name = "nilfs2", 1377 .mount = nilfs_mount, 1378 .kill_sb = kill_block_super, 1379 .fs_flags = FS_REQUIRES_DEV, 1380 }; 1381 MODULE_ALIAS_FS("nilfs2"); 1382 1383 static void nilfs_inode_init_once(void *obj) 1384 { 1385 struct nilfs_inode_info *ii = obj; 1386 1387 INIT_LIST_HEAD(&ii->i_dirty); 1388 #ifdef CONFIG_NILFS_XATTR 1389 init_rwsem(&ii->xattr_sem); 1390 #endif 1391 address_space_init_once(&ii->i_btnode_cache); 1392 ii->i_bmap = &ii->i_bmap_data; 1393 inode_init_once(&ii->vfs_inode); 1394 } 1395 1396 static void nilfs_segbuf_init_once(void *obj) 1397 { 1398 memset(obj, 0, sizeof(struct nilfs_segment_buffer)); 1399 } 1400 1401 static void nilfs_destroy_cachep(void) 1402 { 1403 /* 1404 * Make sure all delayed rcu free inodes are flushed before we 1405 * destroy cache. 1406 */ 1407 rcu_barrier(); 1408 1409 kmem_cache_destroy(nilfs_inode_cachep); 1410 kmem_cache_destroy(nilfs_transaction_cachep); 1411 kmem_cache_destroy(nilfs_segbuf_cachep); 1412 kmem_cache_destroy(nilfs_btree_path_cache); 1413 } 1414 1415 static int __init nilfs_init_cachep(void) 1416 { 1417 nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache", 1418 sizeof(struct nilfs_inode_info), 0, 1419 SLAB_RECLAIM_ACCOUNT|SLAB_ACCOUNT, 1420 nilfs_inode_init_once); 1421 if (!nilfs_inode_cachep) 1422 goto fail; 1423 1424 nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache", 1425 sizeof(struct nilfs_transaction_info), 0, 1426 SLAB_RECLAIM_ACCOUNT, NULL); 1427 if (!nilfs_transaction_cachep) 1428 goto fail; 1429 1430 nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache", 1431 sizeof(struct nilfs_segment_buffer), 0, 1432 SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once); 1433 if (!nilfs_segbuf_cachep) 1434 goto fail; 1435 1436 nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache", 1437 sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX, 1438 0, 0, NULL); 1439 if (!nilfs_btree_path_cache) 1440 goto fail; 1441 1442 return 0; 1443 1444 fail: 1445 nilfs_destroy_cachep(); 1446 return -ENOMEM; 1447 } 1448 1449 static int __init init_nilfs_fs(void) 1450 { 1451 int err; 1452 1453 err = nilfs_init_cachep(); 1454 if (err) 1455 goto fail; 1456 1457 err = nilfs_sysfs_init(); 1458 if (err) 1459 goto free_cachep; 1460 1461 err = register_filesystem(&nilfs_fs_type); 1462 if (err) 1463 goto deinit_sysfs_entry; 1464 1465 printk(KERN_INFO "NILFS version 2 loaded\n"); 1466 return 0; 1467 1468 deinit_sysfs_entry: 1469 nilfs_sysfs_exit(); 1470 free_cachep: 1471 nilfs_destroy_cachep(); 1472 fail: 1473 return err; 1474 } 1475 1476 static void __exit exit_nilfs_fs(void) 1477 { 1478 nilfs_destroy_cachep(); 1479 nilfs_sysfs_exit(); 1480 unregister_filesystem(&nilfs_fs_type); 1481 } 1482 1483 module_init(init_nilfs_fs) 1484 module_exit(exit_nilfs_fs) 1485