1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * NILFS module and super block management. 4 * 5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. 6 * 7 * Written by Ryusuke Konishi. 8 */ 9 /* 10 * linux/fs/ext2/super.c 11 * 12 * Copyright (C) 1992, 1993, 1994, 1995 13 * Remy Card (card@masi.ibp.fr) 14 * Laboratoire MASI - Institut Blaise Pascal 15 * Universite Pierre et Marie Curie (Paris VI) 16 * 17 * from 18 * 19 * linux/fs/minix/inode.c 20 * 21 * Copyright (C) 1991, 1992 Linus Torvalds 22 * 23 * Big-endian to little-endian byte-swapping/bitmaps by 24 * David S. Miller (davem@caip.rutgers.edu), 1995 25 */ 26 27 #include <linux/module.h> 28 #include <linux/string.h> 29 #include <linux/slab.h> 30 #include <linux/init.h> 31 #include <linux/blkdev.h> 32 #include <linux/parser.h> 33 #include <linux/crc32.h> 34 #include <linux/vfs.h> 35 #include <linux/writeback.h> 36 #include <linux/seq_file.h> 37 #include <linux/mount.h> 38 #include "nilfs.h" 39 #include "export.h" 40 #include "mdt.h" 41 #include "alloc.h" 42 #include "btree.h" 43 #include "btnode.h" 44 #include "page.h" 45 #include "cpfile.h" 46 #include "sufile.h" /* nilfs_sufile_resize(), nilfs_sufile_set_alloc_range() */ 47 #include "ifile.h" 48 #include "dat.h" 49 #include "segment.h" 50 #include "segbuf.h" 51 52 MODULE_AUTHOR("NTT Corp."); 53 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem " 54 "(NILFS)"); 55 MODULE_LICENSE("GPL"); 56 57 static struct kmem_cache *nilfs_inode_cachep; 58 struct kmem_cache *nilfs_transaction_cachep; 59 struct kmem_cache *nilfs_segbuf_cachep; 60 struct kmem_cache *nilfs_btree_path_cache; 61 62 static int nilfs_setup_super(struct super_block *sb, int is_mount); 63 static int nilfs_remount(struct super_block *sb, int *flags, char *data); 64 65 void __nilfs_msg(struct super_block *sb, const char *fmt, ...) 66 { 67 struct va_format vaf; 68 va_list args; 69 int level; 70 71 va_start(args, fmt); 72 73 level = printk_get_level(fmt); 74 vaf.fmt = printk_skip_level(fmt); 75 vaf.va = &args; 76 77 if (sb) 78 printk("%c%cNILFS (%s): %pV\n", 79 KERN_SOH_ASCII, level, sb->s_id, &vaf); 80 else 81 printk("%c%cNILFS: %pV\n", 82 KERN_SOH_ASCII, level, &vaf); 83 84 va_end(args); 85 } 86 87 static void nilfs_set_error(struct super_block *sb) 88 { 89 struct the_nilfs *nilfs = sb->s_fs_info; 90 struct nilfs_super_block **sbp; 91 92 down_write(&nilfs->ns_sem); 93 if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) { 94 nilfs->ns_mount_state |= NILFS_ERROR_FS; 95 sbp = nilfs_prepare_super(sb, 0); 96 if (likely(sbp)) { 97 sbp[0]->s_state |= cpu_to_le16(NILFS_ERROR_FS); 98 if (sbp[1]) 99 sbp[1]->s_state |= cpu_to_le16(NILFS_ERROR_FS); 100 nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); 101 } 102 } 103 up_write(&nilfs->ns_sem); 104 } 105 106 /** 107 * __nilfs_error() - report failure condition on a filesystem 108 * 109 * __nilfs_error() sets an ERROR_FS flag on the superblock as well as 110 * reporting an error message. This function should be called when 111 * NILFS detects incoherences or defects of meta data on disk. 112 * 113 * This implements the body of nilfs_error() macro. Normally, 114 * nilfs_error() should be used. As for sustainable errors such as a 115 * single-shot I/O error, nilfs_err() should be used instead. 116 * 117 * Callers should not add a trailing newline since this will do it. 118 */ 119 void __nilfs_error(struct super_block *sb, const char *function, 120 const char *fmt, ...) 121 { 122 struct the_nilfs *nilfs = sb->s_fs_info; 123 struct va_format vaf; 124 va_list args; 125 126 va_start(args, fmt); 127 128 vaf.fmt = fmt; 129 vaf.va = &args; 130 131 printk(KERN_CRIT "NILFS error (device %s): %s: %pV\n", 132 sb->s_id, function, &vaf); 133 134 va_end(args); 135 136 if (!sb_rdonly(sb)) { 137 nilfs_set_error(sb); 138 139 if (nilfs_test_opt(nilfs, ERRORS_RO)) { 140 printk(KERN_CRIT "Remounting filesystem read-only\n"); 141 sb->s_flags |= SB_RDONLY; 142 } 143 } 144 145 if (nilfs_test_opt(nilfs, ERRORS_PANIC)) 146 panic("NILFS (device %s): panic forced after error\n", 147 sb->s_id); 148 } 149 150 struct inode *nilfs_alloc_inode(struct super_block *sb) 151 { 152 struct nilfs_inode_info *ii; 153 154 ii = alloc_inode_sb(sb, nilfs_inode_cachep, GFP_NOFS); 155 if (!ii) 156 return NULL; 157 ii->i_bh = NULL; 158 ii->i_state = 0; 159 ii->i_cno = 0; 160 ii->i_assoc_inode = NULL; 161 ii->i_bmap = &ii->i_bmap_data; 162 return &ii->vfs_inode; 163 } 164 165 static void nilfs_free_inode(struct inode *inode) 166 { 167 if (nilfs_is_metadata_file_inode(inode)) 168 nilfs_mdt_destroy(inode); 169 170 kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode)); 171 } 172 173 static int nilfs_sync_super(struct super_block *sb, int flag) 174 { 175 struct the_nilfs *nilfs = sb->s_fs_info; 176 int err; 177 178 retry: 179 set_buffer_dirty(nilfs->ns_sbh[0]); 180 if (nilfs_test_opt(nilfs, BARRIER)) { 181 err = __sync_dirty_buffer(nilfs->ns_sbh[0], 182 REQ_SYNC | REQ_PREFLUSH | REQ_FUA); 183 } else { 184 err = sync_dirty_buffer(nilfs->ns_sbh[0]); 185 } 186 187 if (unlikely(err)) { 188 nilfs_err(sb, "unable to write superblock: err=%d", err); 189 if (err == -EIO && nilfs->ns_sbh[1]) { 190 /* 191 * sbp[0] points to newer log than sbp[1], 192 * so copy sbp[0] to sbp[1] to take over sbp[0]. 193 */ 194 memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0], 195 nilfs->ns_sbsize); 196 nilfs_fall_back_super_block(nilfs); 197 goto retry; 198 } 199 } else { 200 struct nilfs_super_block *sbp = nilfs->ns_sbp[0]; 201 202 nilfs->ns_sbwcount++; 203 204 /* 205 * The latest segment becomes trailable from the position 206 * written in superblock. 207 */ 208 clear_nilfs_discontinued(nilfs); 209 210 /* update GC protection for recent segments */ 211 if (nilfs->ns_sbh[1]) { 212 if (flag == NILFS_SB_COMMIT_ALL) { 213 set_buffer_dirty(nilfs->ns_sbh[1]); 214 if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0) 215 goto out; 216 } 217 if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) < 218 le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno)) 219 sbp = nilfs->ns_sbp[1]; 220 } 221 222 spin_lock(&nilfs->ns_last_segment_lock); 223 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq); 224 spin_unlock(&nilfs->ns_last_segment_lock); 225 } 226 out: 227 return err; 228 } 229 230 void nilfs_set_log_cursor(struct nilfs_super_block *sbp, 231 struct the_nilfs *nilfs) 232 { 233 sector_t nfreeblocks; 234 235 /* nilfs->ns_sem must be locked by the caller. */ 236 nilfs_count_free_blocks(nilfs, &nfreeblocks); 237 sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks); 238 239 spin_lock(&nilfs->ns_last_segment_lock); 240 sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq); 241 sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg); 242 sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno); 243 spin_unlock(&nilfs->ns_last_segment_lock); 244 } 245 246 struct nilfs_super_block **nilfs_prepare_super(struct super_block *sb, 247 int flip) 248 { 249 struct the_nilfs *nilfs = sb->s_fs_info; 250 struct nilfs_super_block **sbp = nilfs->ns_sbp; 251 252 /* nilfs->ns_sem must be locked by the caller. */ 253 if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) { 254 if (sbp[1] && 255 sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) { 256 memcpy(sbp[0], sbp[1], nilfs->ns_sbsize); 257 } else { 258 nilfs_crit(sb, "superblock broke"); 259 return NULL; 260 } 261 } else if (sbp[1] && 262 sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) { 263 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); 264 } 265 266 if (flip && sbp[1]) 267 nilfs_swap_super_block(nilfs); 268 269 return sbp; 270 } 271 272 int nilfs_commit_super(struct super_block *sb, int flag) 273 { 274 struct the_nilfs *nilfs = sb->s_fs_info; 275 struct nilfs_super_block **sbp = nilfs->ns_sbp; 276 time64_t t; 277 278 /* nilfs->ns_sem must be locked by the caller. */ 279 t = ktime_get_real_seconds(); 280 nilfs->ns_sbwtime = t; 281 sbp[0]->s_wtime = cpu_to_le64(t); 282 sbp[0]->s_sum = 0; 283 sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed, 284 (unsigned char *)sbp[0], 285 nilfs->ns_sbsize)); 286 if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) { 287 sbp[1]->s_wtime = sbp[0]->s_wtime; 288 sbp[1]->s_sum = 0; 289 sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed, 290 (unsigned char *)sbp[1], 291 nilfs->ns_sbsize)); 292 } 293 clear_nilfs_sb_dirty(nilfs); 294 nilfs->ns_flushed_device = 1; 295 /* make sure store to ns_flushed_device cannot be reordered */ 296 smp_wmb(); 297 return nilfs_sync_super(sb, flag); 298 } 299 300 /** 301 * nilfs_cleanup_super() - write filesystem state for cleanup 302 * @sb: super block instance to be unmounted or degraded to read-only 303 * 304 * This function restores state flags in the on-disk super block. 305 * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the 306 * filesystem was not clean previously. 307 */ 308 int nilfs_cleanup_super(struct super_block *sb) 309 { 310 struct the_nilfs *nilfs = sb->s_fs_info; 311 struct nilfs_super_block **sbp; 312 int flag = NILFS_SB_COMMIT; 313 int ret = -EIO; 314 315 sbp = nilfs_prepare_super(sb, 0); 316 if (sbp) { 317 sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state); 318 nilfs_set_log_cursor(sbp[0], nilfs); 319 if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) { 320 /* 321 * make the "clean" flag also to the opposite 322 * super block if both super blocks point to 323 * the same checkpoint. 324 */ 325 sbp[1]->s_state = sbp[0]->s_state; 326 flag = NILFS_SB_COMMIT_ALL; 327 } 328 ret = nilfs_commit_super(sb, flag); 329 } 330 return ret; 331 } 332 333 /** 334 * nilfs_move_2nd_super - relocate secondary super block 335 * @sb: super block instance 336 * @sb2off: new offset of the secondary super block (in bytes) 337 */ 338 static int nilfs_move_2nd_super(struct super_block *sb, loff_t sb2off) 339 { 340 struct the_nilfs *nilfs = sb->s_fs_info; 341 struct buffer_head *nsbh; 342 struct nilfs_super_block *nsbp; 343 sector_t blocknr, newblocknr; 344 unsigned long offset; 345 int sb2i; /* array index of the secondary superblock */ 346 int ret = 0; 347 348 /* nilfs->ns_sem must be locked by the caller. */ 349 if (nilfs->ns_sbh[1] && 350 nilfs->ns_sbh[1]->b_blocknr > nilfs->ns_first_data_block) { 351 sb2i = 1; 352 blocknr = nilfs->ns_sbh[1]->b_blocknr; 353 } else if (nilfs->ns_sbh[0]->b_blocknr > nilfs->ns_first_data_block) { 354 sb2i = 0; 355 blocknr = nilfs->ns_sbh[0]->b_blocknr; 356 } else { 357 sb2i = -1; 358 blocknr = 0; 359 } 360 if (sb2i >= 0 && (u64)blocknr << nilfs->ns_blocksize_bits == sb2off) 361 goto out; /* super block location is unchanged */ 362 363 /* Get new super block buffer */ 364 newblocknr = sb2off >> nilfs->ns_blocksize_bits; 365 offset = sb2off & (nilfs->ns_blocksize - 1); 366 nsbh = sb_getblk(sb, newblocknr); 367 if (!nsbh) { 368 nilfs_warn(sb, 369 "unable to move secondary superblock to block %llu", 370 (unsigned long long)newblocknr); 371 ret = -EIO; 372 goto out; 373 } 374 nsbp = (void *)nsbh->b_data + offset; 375 memset(nsbp, 0, nilfs->ns_blocksize); 376 377 if (sb2i >= 0) { 378 memcpy(nsbp, nilfs->ns_sbp[sb2i], nilfs->ns_sbsize); 379 brelse(nilfs->ns_sbh[sb2i]); 380 nilfs->ns_sbh[sb2i] = nsbh; 381 nilfs->ns_sbp[sb2i] = nsbp; 382 } else if (nilfs->ns_sbh[0]->b_blocknr < nilfs->ns_first_data_block) { 383 /* secondary super block will be restored to index 1 */ 384 nilfs->ns_sbh[1] = nsbh; 385 nilfs->ns_sbp[1] = nsbp; 386 } else { 387 brelse(nsbh); 388 } 389 out: 390 return ret; 391 } 392 393 /** 394 * nilfs_resize_fs - resize the filesystem 395 * @sb: super block instance 396 * @newsize: new size of the filesystem (in bytes) 397 */ 398 int nilfs_resize_fs(struct super_block *sb, __u64 newsize) 399 { 400 struct the_nilfs *nilfs = sb->s_fs_info; 401 struct nilfs_super_block **sbp; 402 __u64 devsize, newnsegs; 403 loff_t sb2off; 404 int ret; 405 406 ret = -ERANGE; 407 devsize = bdev_nr_bytes(sb->s_bdev); 408 if (newsize > devsize) 409 goto out; 410 411 /* 412 * Write lock is required to protect some functions depending 413 * on the number of segments, the number of reserved segments, 414 * and so forth. 415 */ 416 down_write(&nilfs->ns_segctor_sem); 417 418 sb2off = NILFS_SB2_OFFSET_BYTES(newsize); 419 newnsegs = sb2off >> nilfs->ns_blocksize_bits; 420 do_div(newnsegs, nilfs->ns_blocks_per_segment); 421 422 ret = nilfs_sufile_resize(nilfs->ns_sufile, newnsegs); 423 up_write(&nilfs->ns_segctor_sem); 424 if (ret < 0) 425 goto out; 426 427 ret = nilfs_construct_segment(sb); 428 if (ret < 0) 429 goto out; 430 431 down_write(&nilfs->ns_sem); 432 nilfs_move_2nd_super(sb, sb2off); 433 ret = -EIO; 434 sbp = nilfs_prepare_super(sb, 0); 435 if (likely(sbp)) { 436 nilfs_set_log_cursor(sbp[0], nilfs); 437 /* 438 * Drop NILFS_RESIZE_FS flag for compatibility with 439 * mount-time resize which may be implemented in a 440 * future release. 441 */ 442 sbp[0]->s_state = cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & 443 ~NILFS_RESIZE_FS); 444 sbp[0]->s_dev_size = cpu_to_le64(newsize); 445 sbp[0]->s_nsegments = cpu_to_le64(nilfs->ns_nsegments); 446 if (sbp[1]) 447 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); 448 ret = nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); 449 } 450 up_write(&nilfs->ns_sem); 451 452 /* 453 * Reset the range of allocatable segments last. This order 454 * is important in the case of expansion because the secondary 455 * superblock must be protected from log write until migration 456 * completes. 457 */ 458 if (!ret) 459 nilfs_sufile_set_alloc_range(nilfs->ns_sufile, 0, newnsegs - 1); 460 out: 461 return ret; 462 } 463 464 static void nilfs_put_super(struct super_block *sb) 465 { 466 struct the_nilfs *nilfs = sb->s_fs_info; 467 468 nilfs_detach_log_writer(sb); 469 470 if (!sb_rdonly(sb)) { 471 down_write(&nilfs->ns_sem); 472 nilfs_cleanup_super(sb); 473 up_write(&nilfs->ns_sem); 474 } 475 476 iput(nilfs->ns_sufile); 477 iput(nilfs->ns_cpfile); 478 iput(nilfs->ns_dat); 479 480 destroy_nilfs(nilfs); 481 sb->s_fs_info = NULL; 482 } 483 484 static int nilfs_sync_fs(struct super_block *sb, int wait) 485 { 486 struct the_nilfs *nilfs = sb->s_fs_info; 487 struct nilfs_super_block **sbp; 488 int err = 0; 489 490 /* This function is called when super block should be written back */ 491 if (wait) 492 err = nilfs_construct_segment(sb); 493 494 down_write(&nilfs->ns_sem); 495 if (nilfs_sb_dirty(nilfs)) { 496 sbp = nilfs_prepare_super(sb, nilfs_sb_will_flip(nilfs)); 497 if (likely(sbp)) { 498 nilfs_set_log_cursor(sbp[0], nilfs); 499 nilfs_commit_super(sb, NILFS_SB_COMMIT); 500 } 501 } 502 up_write(&nilfs->ns_sem); 503 504 if (!err) 505 err = nilfs_flush_device(nilfs); 506 507 return err; 508 } 509 510 int nilfs_attach_checkpoint(struct super_block *sb, __u64 cno, int curr_mnt, 511 struct nilfs_root **rootp) 512 { 513 struct the_nilfs *nilfs = sb->s_fs_info; 514 struct nilfs_root *root; 515 struct nilfs_checkpoint *raw_cp; 516 struct buffer_head *bh_cp; 517 int err = -ENOMEM; 518 519 root = nilfs_find_or_create_root( 520 nilfs, curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno); 521 if (!root) 522 return err; 523 524 if (root->ifile) 525 goto reuse; /* already attached checkpoint */ 526 527 down_read(&nilfs->ns_segctor_sem); 528 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp, 529 &bh_cp); 530 up_read(&nilfs->ns_segctor_sem); 531 if (unlikely(err)) { 532 if (err == -ENOENT || err == -EINVAL) { 533 nilfs_err(sb, 534 "Invalid checkpoint (checkpoint number=%llu)", 535 (unsigned long long)cno); 536 err = -EINVAL; 537 } 538 goto failed; 539 } 540 541 err = nilfs_ifile_read(sb, root, nilfs->ns_inode_size, 542 &raw_cp->cp_ifile_inode, &root->ifile); 543 if (err) 544 goto failed_bh; 545 546 atomic64_set(&root->inodes_count, 547 le64_to_cpu(raw_cp->cp_inodes_count)); 548 atomic64_set(&root->blocks_count, 549 le64_to_cpu(raw_cp->cp_blocks_count)); 550 551 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp); 552 553 reuse: 554 *rootp = root; 555 return 0; 556 557 failed_bh: 558 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp); 559 failed: 560 nilfs_put_root(root); 561 562 return err; 563 } 564 565 static int nilfs_freeze(struct super_block *sb) 566 { 567 struct the_nilfs *nilfs = sb->s_fs_info; 568 int err; 569 570 if (sb_rdonly(sb)) 571 return 0; 572 573 /* Mark super block clean */ 574 down_write(&nilfs->ns_sem); 575 err = nilfs_cleanup_super(sb); 576 up_write(&nilfs->ns_sem); 577 return err; 578 } 579 580 static int nilfs_unfreeze(struct super_block *sb) 581 { 582 struct the_nilfs *nilfs = sb->s_fs_info; 583 584 if (sb_rdonly(sb)) 585 return 0; 586 587 down_write(&nilfs->ns_sem); 588 nilfs_setup_super(sb, false); 589 up_write(&nilfs->ns_sem); 590 return 0; 591 } 592 593 static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf) 594 { 595 struct super_block *sb = dentry->d_sb; 596 struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root; 597 struct the_nilfs *nilfs = root->nilfs; 598 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 599 unsigned long long blocks; 600 unsigned long overhead; 601 unsigned long nrsvblocks; 602 sector_t nfreeblocks; 603 u64 nmaxinodes, nfreeinodes; 604 int err; 605 606 /* 607 * Compute all of the segment blocks 608 * 609 * The blocks before first segment and after last segment 610 * are excluded. 611 */ 612 blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments 613 - nilfs->ns_first_data_block; 614 nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment; 615 616 /* 617 * Compute the overhead 618 * 619 * When distributing meta data blocks outside segment structure, 620 * We must count them as the overhead. 621 */ 622 overhead = 0; 623 624 err = nilfs_count_free_blocks(nilfs, &nfreeblocks); 625 if (unlikely(err)) 626 return err; 627 628 err = nilfs_ifile_count_free_inodes(root->ifile, 629 &nmaxinodes, &nfreeinodes); 630 if (unlikely(err)) { 631 nilfs_warn(sb, "failed to count free inodes: err=%d", err); 632 if (err == -ERANGE) { 633 /* 634 * If nilfs_palloc_count_max_entries() returns 635 * -ERANGE error code then we simply treat 636 * curent inodes count as maximum possible and 637 * zero as free inodes value. 638 */ 639 nmaxinodes = atomic64_read(&root->inodes_count); 640 nfreeinodes = 0; 641 err = 0; 642 } else 643 return err; 644 } 645 646 buf->f_type = NILFS_SUPER_MAGIC; 647 buf->f_bsize = sb->s_blocksize; 648 buf->f_blocks = blocks - overhead; 649 buf->f_bfree = nfreeblocks; 650 buf->f_bavail = (buf->f_bfree >= nrsvblocks) ? 651 (buf->f_bfree - nrsvblocks) : 0; 652 buf->f_files = nmaxinodes; 653 buf->f_ffree = nfreeinodes; 654 buf->f_namelen = NILFS_NAME_LEN; 655 buf->f_fsid = u64_to_fsid(id); 656 657 return 0; 658 } 659 660 static int nilfs_show_options(struct seq_file *seq, struct dentry *dentry) 661 { 662 struct super_block *sb = dentry->d_sb; 663 struct the_nilfs *nilfs = sb->s_fs_info; 664 struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root; 665 666 if (!nilfs_test_opt(nilfs, BARRIER)) 667 seq_puts(seq, ",nobarrier"); 668 if (root->cno != NILFS_CPTREE_CURRENT_CNO) 669 seq_printf(seq, ",cp=%llu", (unsigned long long)root->cno); 670 if (nilfs_test_opt(nilfs, ERRORS_PANIC)) 671 seq_puts(seq, ",errors=panic"); 672 if (nilfs_test_opt(nilfs, ERRORS_CONT)) 673 seq_puts(seq, ",errors=continue"); 674 if (nilfs_test_opt(nilfs, STRICT_ORDER)) 675 seq_puts(seq, ",order=strict"); 676 if (nilfs_test_opt(nilfs, NORECOVERY)) 677 seq_puts(seq, ",norecovery"); 678 if (nilfs_test_opt(nilfs, DISCARD)) 679 seq_puts(seq, ",discard"); 680 681 return 0; 682 } 683 684 static const struct super_operations nilfs_sops = { 685 .alloc_inode = nilfs_alloc_inode, 686 .free_inode = nilfs_free_inode, 687 .dirty_inode = nilfs_dirty_inode, 688 .evict_inode = nilfs_evict_inode, 689 .put_super = nilfs_put_super, 690 .sync_fs = nilfs_sync_fs, 691 .freeze_fs = nilfs_freeze, 692 .unfreeze_fs = nilfs_unfreeze, 693 .statfs = nilfs_statfs, 694 .remount_fs = nilfs_remount, 695 .show_options = nilfs_show_options 696 }; 697 698 enum { 699 Opt_err_cont, Opt_err_panic, Opt_err_ro, 700 Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery, 701 Opt_discard, Opt_nodiscard, Opt_err, 702 }; 703 704 static match_table_t tokens = { 705 {Opt_err_cont, "errors=continue"}, 706 {Opt_err_panic, "errors=panic"}, 707 {Opt_err_ro, "errors=remount-ro"}, 708 {Opt_barrier, "barrier"}, 709 {Opt_nobarrier, "nobarrier"}, 710 {Opt_snapshot, "cp=%u"}, 711 {Opt_order, "order=%s"}, 712 {Opt_norecovery, "norecovery"}, 713 {Opt_discard, "discard"}, 714 {Opt_nodiscard, "nodiscard"}, 715 {Opt_err, NULL} 716 }; 717 718 static int parse_options(char *options, struct super_block *sb, int is_remount) 719 { 720 struct the_nilfs *nilfs = sb->s_fs_info; 721 char *p; 722 substring_t args[MAX_OPT_ARGS]; 723 724 if (!options) 725 return 1; 726 727 while ((p = strsep(&options, ",")) != NULL) { 728 int token; 729 730 if (!*p) 731 continue; 732 733 token = match_token(p, tokens, args); 734 switch (token) { 735 case Opt_barrier: 736 nilfs_set_opt(nilfs, BARRIER); 737 break; 738 case Opt_nobarrier: 739 nilfs_clear_opt(nilfs, BARRIER); 740 break; 741 case Opt_order: 742 if (strcmp(args[0].from, "relaxed") == 0) 743 /* Ordered data semantics */ 744 nilfs_clear_opt(nilfs, STRICT_ORDER); 745 else if (strcmp(args[0].from, "strict") == 0) 746 /* Strict in-order semantics */ 747 nilfs_set_opt(nilfs, STRICT_ORDER); 748 else 749 return 0; 750 break; 751 case Opt_err_panic: 752 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_PANIC); 753 break; 754 case Opt_err_ro: 755 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_RO); 756 break; 757 case Opt_err_cont: 758 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_CONT); 759 break; 760 case Opt_snapshot: 761 if (is_remount) { 762 nilfs_err(sb, 763 "\"%s\" option is invalid for remount", 764 p); 765 return 0; 766 } 767 break; 768 case Opt_norecovery: 769 nilfs_set_opt(nilfs, NORECOVERY); 770 break; 771 case Opt_discard: 772 nilfs_set_opt(nilfs, DISCARD); 773 break; 774 case Opt_nodiscard: 775 nilfs_clear_opt(nilfs, DISCARD); 776 break; 777 default: 778 nilfs_err(sb, "unrecognized mount option \"%s\"", p); 779 return 0; 780 } 781 } 782 return 1; 783 } 784 785 static inline void 786 nilfs_set_default_options(struct super_block *sb, 787 struct nilfs_super_block *sbp) 788 { 789 struct the_nilfs *nilfs = sb->s_fs_info; 790 791 nilfs->ns_mount_opt = 792 NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER; 793 } 794 795 static int nilfs_setup_super(struct super_block *sb, int is_mount) 796 { 797 struct the_nilfs *nilfs = sb->s_fs_info; 798 struct nilfs_super_block **sbp; 799 int max_mnt_count; 800 int mnt_count; 801 802 /* nilfs->ns_sem must be locked by the caller. */ 803 sbp = nilfs_prepare_super(sb, 0); 804 if (!sbp) 805 return -EIO; 806 807 if (!is_mount) 808 goto skip_mount_setup; 809 810 max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count); 811 mnt_count = le16_to_cpu(sbp[0]->s_mnt_count); 812 813 if (nilfs->ns_mount_state & NILFS_ERROR_FS) { 814 nilfs_warn(sb, "mounting fs with errors"); 815 #if 0 816 } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) { 817 nilfs_warn(sb, "maximal mount count reached"); 818 #endif 819 } 820 if (!max_mnt_count) 821 sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT); 822 823 sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1); 824 sbp[0]->s_mtime = cpu_to_le64(ktime_get_real_seconds()); 825 826 skip_mount_setup: 827 sbp[0]->s_state = 828 cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS); 829 /* synchronize sbp[1] with sbp[0] */ 830 if (sbp[1]) 831 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); 832 return nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); 833 } 834 835 struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb, 836 u64 pos, int blocksize, 837 struct buffer_head **pbh) 838 { 839 unsigned long long sb_index = pos; 840 unsigned long offset; 841 842 offset = do_div(sb_index, blocksize); 843 *pbh = sb_bread(sb, sb_index); 844 if (!*pbh) 845 return NULL; 846 return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset); 847 } 848 849 int nilfs_store_magic_and_option(struct super_block *sb, 850 struct nilfs_super_block *sbp, 851 char *data) 852 { 853 struct the_nilfs *nilfs = sb->s_fs_info; 854 855 sb->s_magic = le16_to_cpu(sbp->s_magic); 856 857 /* FS independent flags */ 858 #ifdef NILFS_ATIME_DISABLE 859 sb->s_flags |= SB_NOATIME; 860 #endif 861 862 nilfs_set_default_options(sb, sbp); 863 864 nilfs->ns_resuid = le16_to_cpu(sbp->s_def_resuid); 865 nilfs->ns_resgid = le16_to_cpu(sbp->s_def_resgid); 866 nilfs->ns_interval = le32_to_cpu(sbp->s_c_interval); 867 nilfs->ns_watermark = le32_to_cpu(sbp->s_c_block_max); 868 869 return !parse_options(data, sb, 0) ? -EINVAL : 0; 870 } 871 872 int nilfs_check_feature_compatibility(struct super_block *sb, 873 struct nilfs_super_block *sbp) 874 { 875 __u64 features; 876 877 features = le64_to_cpu(sbp->s_feature_incompat) & 878 ~NILFS_FEATURE_INCOMPAT_SUPP; 879 if (features) { 880 nilfs_err(sb, 881 "couldn't mount because of unsupported optional features (%llx)", 882 (unsigned long long)features); 883 return -EINVAL; 884 } 885 features = le64_to_cpu(sbp->s_feature_compat_ro) & 886 ~NILFS_FEATURE_COMPAT_RO_SUPP; 887 if (!sb_rdonly(sb) && features) { 888 nilfs_err(sb, 889 "couldn't mount RDWR because of unsupported optional features (%llx)", 890 (unsigned long long)features); 891 return -EINVAL; 892 } 893 return 0; 894 } 895 896 static int nilfs_get_root_dentry(struct super_block *sb, 897 struct nilfs_root *root, 898 struct dentry **root_dentry) 899 { 900 struct inode *inode; 901 struct dentry *dentry; 902 int ret = 0; 903 904 inode = nilfs_iget(sb, root, NILFS_ROOT_INO); 905 if (IS_ERR(inode)) { 906 ret = PTR_ERR(inode); 907 nilfs_err(sb, "error %d getting root inode", ret); 908 goto out; 909 } 910 if (!S_ISDIR(inode->i_mode) || !inode->i_blocks || !inode->i_size) { 911 iput(inode); 912 nilfs_err(sb, "corrupt root inode"); 913 ret = -EINVAL; 914 goto out; 915 } 916 917 if (root->cno == NILFS_CPTREE_CURRENT_CNO) { 918 dentry = d_find_alias(inode); 919 if (!dentry) { 920 dentry = d_make_root(inode); 921 if (!dentry) { 922 ret = -ENOMEM; 923 goto failed_dentry; 924 } 925 } else { 926 iput(inode); 927 } 928 } else { 929 dentry = d_obtain_root(inode); 930 if (IS_ERR(dentry)) { 931 ret = PTR_ERR(dentry); 932 goto failed_dentry; 933 } 934 } 935 *root_dentry = dentry; 936 out: 937 return ret; 938 939 failed_dentry: 940 nilfs_err(sb, "error %d getting root dentry", ret); 941 goto out; 942 } 943 944 static int nilfs_attach_snapshot(struct super_block *s, __u64 cno, 945 struct dentry **root_dentry) 946 { 947 struct the_nilfs *nilfs = s->s_fs_info; 948 struct nilfs_root *root; 949 int ret; 950 951 mutex_lock(&nilfs->ns_snapshot_mount_mutex); 952 953 down_read(&nilfs->ns_segctor_sem); 954 ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno); 955 up_read(&nilfs->ns_segctor_sem); 956 if (ret < 0) { 957 ret = (ret == -ENOENT) ? -EINVAL : ret; 958 goto out; 959 } else if (!ret) { 960 nilfs_err(s, 961 "The specified checkpoint is not a snapshot (checkpoint number=%llu)", 962 (unsigned long long)cno); 963 ret = -EINVAL; 964 goto out; 965 } 966 967 ret = nilfs_attach_checkpoint(s, cno, false, &root); 968 if (ret) { 969 nilfs_err(s, 970 "error %d while loading snapshot (checkpoint number=%llu)", 971 ret, (unsigned long long)cno); 972 goto out; 973 } 974 ret = nilfs_get_root_dentry(s, root, root_dentry); 975 nilfs_put_root(root); 976 out: 977 mutex_unlock(&nilfs->ns_snapshot_mount_mutex); 978 return ret; 979 } 980 981 /** 982 * nilfs_tree_is_busy() - try to shrink dentries of a checkpoint 983 * @root_dentry: root dentry of the tree to be shrunk 984 * 985 * This function returns true if the tree was in-use. 986 */ 987 static bool nilfs_tree_is_busy(struct dentry *root_dentry) 988 { 989 shrink_dcache_parent(root_dentry); 990 return d_count(root_dentry) > 1; 991 } 992 993 int nilfs_checkpoint_is_mounted(struct super_block *sb, __u64 cno) 994 { 995 struct the_nilfs *nilfs = sb->s_fs_info; 996 struct nilfs_root *root; 997 struct inode *inode; 998 struct dentry *dentry; 999 int ret; 1000 1001 if (cno > nilfs->ns_cno) 1002 return false; 1003 1004 if (cno >= nilfs_last_cno(nilfs)) 1005 return true; /* protect recent checkpoints */ 1006 1007 ret = false; 1008 root = nilfs_lookup_root(nilfs, cno); 1009 if (root) { 1010 inode = nilfs_ilookup(sb, root, NILFS_ROOT_INO); 1011 if (inode) { 1012 dentry = d_find_alias(inode); 1013 if (dentry) { 1014 ret = nilfs_tree_is_busy(dentry); 1015 dput(dentry); 1016 } 1017 iput(inode); 1018 } 1019 nilfs_put_root(root); 1020 } 1021 return ret; 1022 } 1023 1024 /** 1025 * nilfs_fill_super() - initialize a super block instance 1026 * @sb: super_block 1027 * @data: mount options 1028 * @silent: silent mode flag 1029 * 1030 * This function is called exclusively by nilfs->ns_mount_mutex. 1031 * So, the recovery process is protected from other simultaneous mounts. 1032 */ 1033 static int 1034 nilfs_fill_super(struct super_block *sb, void *data, int silent) 1035 { 1036 struct the_nilfs *nilfs; 1037 struct nilfs_root *fsroot; 1038 __u64 cno; 1039 int err; 1040 1041 nilfs = alloc_nilfs(sb); 1042 if (!nilfs) 1043 return -ENOMEM; 1044 1045 sb->s_fs_info = nilfs; 1046 1047 err = init_nilfs(nilfs, sb, (char *)data); 1048 if (err) 1049 goto failed_nilfs; 1050 1051 sb->s_op = &nilfs_sops; 1052 sb->s_export_op = &nilfs_export_ops; 1053 sb->s_root = NULL; 1054 sb->s_time_gran = 1; 1055 sb->s_max_links = NILFS_LINK_MAX; 1056 1057 sb->s_bdi = bdi_get(sb->s_bdev->bd_disk->bdi); 1058 1059 err = load_nilfs(nilfs, sb); 1060 if (err) 1061 goto failed_nilfs; 1062 1063 cno = nilfs_last_cno(nilfs); 1064 err = nilfs_attach_checkpoint(sb, cno, true, &fsroot); 1065 if (err) { 1066 nilfs_err(sb, 1067 "error %d while loading last checkpoint (checkpoint number=%llu)", 1068 err, (unsigned long long)cno); 1069 goto failed_unload; 1070 } 1071 1072 if (!sb_rdonly(sb)) { 1073 err = nilfs_attach_log_writer(sb, fsroot); 1074 if (err) 1075 goto failed_checkpoint; 1076 } 1077 1078 err = nilfs_get_root_dentry(sb, fsroot, &sb->s_root); 1079 if (err) 1080 goto failed_segctor; 1081 1082 nilfs_put_root(fsroot); 1083 1084 if (!sb_rdonly(sb)) { 1085 down_write(&nilfs->ns_sem); 1086 nilfs_setup_super(sb, true); 1087 up_write(&nilfs->ns_sem); 1088 } 1089 1090 return 0; 1091 1092 failed_segctor: 1093 nilfs_detach_log_writer(sb); 1094 1095 failed_checkpoint: 1096 nilfs_put_root(fsroot); 1097 1098 failed_unload: 1099 iput(nilfs->ns_sufile); 1100 iput(nilfs->ns_cpfile); 1101 iput(nilfs->ns_dat); 1102 1103 failed_nilfs: 1104 destroy_nilfs(nilfs); 1105 return err; 1106 } 1107 1108 static int nilfs_remount(struct super_block *sb, int *flags, char *data) 1109 { 1110 struct the_nilfs *nilfs = sb->s_fs_info; 1111 unsigned long old_sb_flags; 1112 unsigned long old_mount_opt; 1113 int err; 1114 1115 sync_filesystem(sb); 1116 old_sb_flags = sb->s_flags; 1117 old_mount_opt = nilfs->ns_mount_opt; 1118 1119 if (!parse_options(data, sb, 1)) { 1120 err = -EINVAL; 1121 goto restore_opts; 1122 } 1123 sb->s_flags = (sb->s_flags & ~SB_POSIXACL); 1124 1125 err = -EINVAL; 1126 1127 if (!nilfs_valid_fs(nilfs)) { 1128 nilfs_warn(sb, 1129 "couldn't remount because the filesystem is in an incomplete recovery state"); 1130 goto restore_opts; 1131 } 1132 1133 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb)) 1134 goto out; 1135 if (*flags & SB_RDONLY) { 1136 sb->s_flags |= SB_RDONLY; 1137 1138 /* 1139 * Remounting a valid RW partition RDONLY, so set 1140 * the RDONLY flag and then mark the partition as valid again. 1141 */ 1142 down_write(&nilfs->ns_sem); 1143 nilfs_cleanup_super(sb); 1144 up_write(&nilfs->ns_sem); 1145 } else { 1146 __u64 features; 1147 struct nilfs_root *root; 1148 1149 /* 1150 * Mounting a RDONLY partition read-write, so reread and 1151 * store the current valid flag. (It may have been changed 1152 * by fsck since we originally mounted the partition.) 1153 */ 1154 down_read(&nilfs->ns_sem); 1155 features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) & 1156 ~NILFS_FEATURE_COMPAT_RO_SUPP; 1157 up_read(&nilfs->ns_sem); 1158 if (features) { 1159 nilfs_warn(sb, 1160 "couldn't remount RDWR because of unsupported optional features (%llx)", 1161 (unsigned long long)features); 1162 err = -EROFS; 1163 goto restore_opts; 1164 } 1165 1166 sb->s_flags &= ~SB_RDONLY; 1167 1168 root = NILFS_I(d_inode(sb->s_root))->i_root; 1169 err = nilfs_attach_log_writer(sb, root); 1170 if (err) 1171 goto restore_opts; 1172 1173 down_write(&nilfs->ns_sem); 1174 nilfs_setup_super(sb, true); 1175 up_write(&nilfs->ns_sem); 1176 } 1177 out: 1178 return 0; 1179 1180 restore_opts: 1181 sb->s_flags = old_sb_flags; 1182 nilfs->ns_mount_opt = old_mount_opt; 1183 return err; 1184 } 1185 1186 struct nilfs_super_data { 1187 struct block_device *bdev; 1188 __u64 cno; 1189 int flags; 1190 }; 1191 1192 static int nilfs_parse_snapshot_option(const char *option, 1193 const substring_t *arg, 1194 struct nilfs_super_data *sd) 1195 { 1196 unsigned long long val; 1197 const char *msg = NULL; 1198 int err; 1199 1200 if (!(sd->flags & SB_RDONLY)) { 1201 msg = "read-only option is not specified"; 1202 goto parse_error; 1203 } 1204 1205 err = kstrtoull(arg->from, 0, &val); 1206 if (err) { 1207 if (err == -ERANGE) 1208 msg = "too large checkpoint number"; 1209 else 1210 msg = "malformed argument"; 1211 goto parse_error; 1212 } else if (val == 0) { 1213 msg = "invalid checkpoint number 0"; 1214 goto parse_error; 1215 } 1216 sd->cno = val; 1217 return 0; 1218 1219 parse_error: 1220 nilfs_err(NULL, "invalid option \"%s\": %s", option, msg); 1221 return 1; 1222 } 1223 1224 /** 1225 * nilfs_identify - pre-read mount options needed to identify mount instance 1226 * @data: mount options 1227 * @sd: nilfs_super_data 1228 */ 1229 static int nilfs_identify(char *data, struct nilfs_super_data *sd) 1230 { 1231 char *p, *options = data; 1232 substring_t args[MAX_OPT_ARGS]; 1233 int token; 1234 int ret = 0; 1235 1236 do { 1237 p = strsep(&options, ","); 1238 if (p != NULL && *p) { 1239 token = match_token(p, tokens, args); 1240 if (token == Opt_snapshot) 1241 ret = nilfs_parse_snapshot_option(p, &args[0], 1242 sd); 1243 } 1244 if (!options) 1245 break; 1246 BUG_ON(options == data); 1247 *(options - 1) = ','; 1248 } while (!ret); 1249 return ret; 1250 } 1251 1252 static int nilfs_set_bdev_super(struct super_block *s, void *data) 1253 { 1254 s->s_bdev = data; 1255 s->s_dev = s->s_bdev->bd_dev; 1256 return 0; 1257 } 1258 1259 static int nilfs_test_bdev_super(struct super_block *s, void *data) 1260 { 1261 return (void *)s->s_bdev == data; 1262 } 1263 1264 static struct dentry * 1265 nilfs_mount(struct file_system_type *fs_type, int flags, 1266 const char *dev_name, void *data) 1267 { 1268 struct nilfs_super_data sd; 1269 struct super_block *s; 1270 fmode_t mode = FMODE_READ | FMODE_EXCL; 1271 struct dentry *root_dentry; 1272 int err, s_new = false; 1273 1274 if (!(flags & SB_RDONLY)) 1275 mode |= FMODE_WRITE; 1276 1277 sd.bdev = blkdev_get_by_path(dev_name, mode, fs_type); 1278 if (IS_ERR(sd.bdev)) 1279 return ERR_CAST(sd.bdev); 1280 1281 sd.cno = 0; 1282 sd.flags = flags; 1283 if (nilfs_identify((char *)data, &sd)) { 1284 err = -EINVAL; 1285 goto failed; 1286 } 1287 1288 /* 1289 * once the super is inserted into the list by sget, s_umount 1290 * will protect the lockfs code from trying to start a snapshot 1291 * while we are mounting 1292 */ 1293 mutex_lock(&sd.bdev->bd_fsfreeze_mutex); 1294 if (sd.bdev->bd_fsfreeze_count > 0) { 1295 mutex_unlock(&sd.bdev->bd_fsfreeze_mutex); 1296 err = -EBUSY; 1297 goto failed; 1298 } 1299 s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, flags, 1300 sd.bdev); 1301 mutex_unlock(&sd.bdev->bd_fsfreeze_mutex); 1302 if (IS_ERR(s)) { 1303 err = PTR_ERR(s); 1304 goto failed; 1305 } 1306 1307 if (!s->s_root) { 1308 s_new = true; 1309 1310 /* New superblock instance created */ 1311 s->s_mode = mode; 1312 snprintf(s->s_id, sizeof(s->s_id), "%pg", sd.bdev); 1313 sb_set_blocksize(s, block_size(sd.bdev)); 1314 1315 err = nilfs_fill_super(s, data, flags & SB_SILENT ? 1 : 0); 1316 if (err) 1317 goto failed_super; 1318 1319 s->s_flags |= SB_ACTIVE; 1320 } else if (!sd.cno) { 1321 if (nilfs_tree_is_busy(s->s_root)) { 1322 if ((flags ^ s->s_flags) & SB_RDONLY) { 1323 nilfs_err(s, 1324 "the device already has a %s mount.", 1325 sb_rdonly(s) ? "read-only" : "read/write"); 1326 err = -EBUSY; 1327 goto failed_super; 1328 } 1329 } else { 1330 /* 1331 * Try remount to setup mount states if the current 1332 * tree is not mounted and only snapshots use this sb. 1333 */ 1334 err = nilfs_remount(s, &flags, data); 1335 if (err) 1336 goto failed_super; 1337 } 1338 } 1339 1340 if (sd.cno) { 1341 err = nilfs_attach_snapshot(s, sd.cno, &root_dentry); 1342 if (err) 1343 goto failed_super; 1344 } else { 1345 root_dentry = dget(s->s_root); 1346 } 1347 1348 if (!s_new) 1349 blkdev_put(sd.bdev, mode); 1350 1351 return root_dentry; 1352 1353 failed_super: 1354 deactivate_locked_super(s); 1355 1356 failed: 1357 if (!s_new) 1358 blkdev_put(sd.bdev, mode); 1359 return ERR_PTR(err); 1360 } 1361 1362 struct file_system_type nilfs_fs_type = { 1363 .owner = THIS_MODULE, 1364 .name = "nilfs2", 1365 .mount = nilfs_mount, 1366 .kill_sb = kill_block_super, 1367 .fs_flags = FS_REQUIRES_DEV, 1368 }; 1369 MODULE_ALIAS_FS("nilfs2"); 1370 1371 static void nilfs_inode_init_once(void *obj) 1372 { 1373 struct nilfs_inode_info *ii = obj; 1374 1375 INIT_LIST_HEAD(&ii->i_dirty); 1376 #ifdef CONFIG_NILFS_XATTR 1377 init_rwsem(&ii->xattr_sem); 1378 #endif 1379 inode_init_once(&ii->vfs_inode); 1380 } 1381 1382 static void nilfs_segbuf_init_once(void *obj) 1383 { 1384 memset(obj, 0, sizeof(struct nilfs_segment_buffer)); 1385 } 1386 1387 static void nilfs_destroy_cachep(void) 1388 { 1389 /* 1390 * Make sure all delayed rcu free inodes are flushed before we 1391 * destroy cache. 1392 */ 1393 rcu_barrier(); 1394 1395 kmem_cache_destroy(nilfs_inode_cachep); 1396 kmem_cache_destroy(nilfs_transaction_cachep); 1397 kmem_cache_destroy(nilfs_segbuf_cachep); 1398 kmem_cache_destroy(nilfs_btree_path_cache); 1399 } 1400 1401 static int __init nilfs_init_cachep(void) 1402 { 1403 nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache", 1404 sizeof(struct nilfs_inode_info), 0, 1405 SLAB_RECLAIM_ACCOUNT|SLAB_ACCOUNT, 1406 nilfs_inode_init_once); 1407 if (!nilfs_inode_cachep) 1408 goto fail; 1409 1410 nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache", 1411 sizeof(struct nilfs_transaction_info), 0, 1412 SLAB_RECLAIM_ACCOUNT, NULL); 1413 if (!nilfs_transaction_cachep) 1414 goto fail; 1415 1416 nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache", 1417 sizeof(struct nilfs_segment_buffer), 0, 1418 SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once); 1419 if (!nilfs_segbuf_cachep) 1420 goto fail; 1421 1422 nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache", 1423 sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX, 1424 0, 0, NULL); 1425 if (!nilfs_btree_path_cache) 1426 goto fail; 1427 1428 return 0; 1429 1430 fail: 1431 nilfs_destroy_cachep(); 1432 return -ENOMEM; 1433 } 1434 1435 static int __init init_nilfs_fs(void) 1436 { 1437 int err; 1438 1439 err = nilfs_init_cachep(); 1440 if (err) 1441 goto fail; 1442 1443 err = nilfs_sysfs_init(); 1444 if (err) 1445 goto free_cachep; 1446 1447 err = register_filesystem(&nilfs_fs_type); 1448 if (err) 1449 goto deinit_sysfs_entry; 1450 1451 printk(KERN_INFO "NILFS version 2 loaded\n"); 1452 return 0; 1453 1454 deinit_sysfs_entry: 1455 nilfs_sysfs_exit(); 1456 free_cachep: 1457 nilfs_destroy_cachep(); 1458 fail: 1459 return err; 1460 } 1461 1462 static void __exit exit_nilfs_fs(void) 1463 { 1464 nilfs_destroy_cachep(); 1465 nilfs_sysfs_exit(); 1466 unregister_filesystem(&nilfs_fs_type); 1467 } 1468 1469 module_init(init_nilfs_fs) 1470 module_exit(exit_nilfs_fs) 1471