1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * super.c - 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 = kmem_cache_alloc(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 nilfs_mapping_init(&ii->i_btnode_cache, &ii->vfs_inode); 161 return &ii->vfs_inode; 162 } 163 164 static void nilfs_free_inode(struct inode *inode) 165 { 166 if (nilfs_is_metadata_file_inode(inode)) 167 nilfs_mdt_destroy(inode); 168 169 kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode)); 170 } 171 172 static int nilfs_sync_super(struct super_block *sb, int flag) 173 { 174 struct the_nilfs *nilfs = sb->s_fs_info; 175 int err; 176 177 retry: 178 set_buffer_dirty(nilfs->ns_sbh[0]); 179 if (nilfs_test_opt(nilfs, BARRIER)) { 180 err = __sync_dirty_buffer(nilfs->ns_sbh[0], 181 REQ_SYNC | REQ_PREFLUSH | REQ_FUA); 182 } else { 183 err = sync_dirty_buffer(nilfs->ns_sbh[0]); 184 } 185 186 if (unlikely(err)) { 187 nilfs_err(sb, "unable to write superblock: err=%d", err); 188 if (err == -EIO && nilfs->ns_sbh[1]) { 189 /* 190 * sbp[0] points to newer log than sbp[1], 191 * so copy sbp[0] to sbp[1] to take over sbp[0]. 192 */ 193 memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0], 194 nilfs->ns_sbsize); 195 nilfs_fall_back_super_block(nilfs); 196 goto retry; 197 } 198 } else { 199 struct nilfs_super_block *sbp = nilfs->ns_sbp[0]; 200 201 nilfs->ns_sbwcount++; 202 203 /* 204 * The latest segment becomes trailable from the position 205 * written in superblock. 206 */ 207 clear_nilfs_discontinued(nilfs); 208 209 /* update GC protection for recent segments */ 210 if (nilfs->ns_sbh[1]) { 211 if (flag == NILFS_SB_COMMIT_ALL) { 212 set_buffer_dirty(nilfs->ns_sbh[1]); 213 if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0) 214 goto out; 215 } 216 if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) < 217 le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno)) 218 sbp = nilfs->ns_sbp[1]; 219 } 220 221 spin_lock(&nilfs->ns_last_segment_lock); 222 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq); 223 spin_unlock(&nilfs->ns_last_segment_lock); 224 } 225 out: 226 return err; 227 } 228 229 void nilfs_set_log_cursor(struct nilfs_super_block *sbp, 230 struct the_nilfs *nilfs) 231 { 232 sector_t nfreeblocks; 233 234 /* nilfs->ns_sem must be locked by the caller. */ 235 nilfs_count_free_blocks(nilfs, &nfreeblocks); 236 sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks); 237 238 spin_lock(&nilfs->ns_last_segment_lock); 239 sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq); 240 sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg); 241 sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno); 242 spin_unlock(&nilfs->ns_last_segment_lock); 243 } 244 245 struct nilfs_super_block **nilfs_prepare_super(struct super_block *sb, 246 int flip) 247 { 248 struct the_nilfs *nilfs = sb->s_fs_info; 249 struct nilfs_super_block **sbp = nilfs->ns_sbp; 250 251 /* nilfs->ns_sem must be locked by the caller. */ 252 if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) { 253 if (sbp[1] && 254 sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) { 255 memcpy(sbp[0], sbp[1], nilfs->ns_sbsize); 256 } else { 257 nilfs_crit(sb, "superblock broke"); 258 return NULL; 259 } 260 } else if (sbp[1] && 261 sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) { 262 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); 263 } 264 265 if (flip && sbp[1]) 266 nilfs_swap_super_block(nilfs); 267 268 return sbp; 269 } 270 271 int nilfs_commit_super(struct super_block *sb, int flag) 272 { 273 struct the_nilfs *nilfs = sb->s_fs_info; 274 struct nilfs_super_block **sbp = nilfs->ns_sbp; 275 time64_t t; 276 277 /* nilfs->ns_sem must be locked by the caller. */ 278 t = ktime_get_real_seconds(); 279 nilfs->ns_sbwtime = t; 280 sbp[0]->s_wtime = cpu_to_le64(t); 281 sbp[0]->s_sum = 0; 282 sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed, 283 (unsigned char *)sbp[0], 284 nilfs->ns_sbsize)); 285 if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) { 286 sbp[1]->s_wtime = sbp[0]->s_wtime; 287 sbp[1]->s_sum = 0; 288 sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed, 289 (unsigned char *)sbp[1], 290 nilfs->ns_sbsize)); 291 } 292 clear_nilfs_sb_dirty(nilfs); 293 nilfs->ns_flushed_device = 1; 294 /* make sure store to ns_flushed_device cannot be reordered */ 295 smp_wmb(); 296 return nilfs_sync_super(sb, flag); 297 } 298 299 /** 300 * nilfs_cleanup_super() - write filesystem state for cleanup 301 * @sb: super block instance to be unmounted or degraded to read-only 302 * 303 * This function restores state flags in the on-disk super block. 304 * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the 305 * filesystem was not clean previously. 306 */ 307 int nilfs_cleanup_super(struct super_block *sb) 308 { 309 struct the_nilfs *nilfs = sb->s_fs_info; 310 struct nilfs_super_block **sbp; 311 int flag = NILFS_SB_COMMIT; 312 int ret = -EIO; 313 314 sbp = nilfs_prepare_super(sb, 0); 315 if (sbp) { 316 sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state); 317 nilfs_set_log_cursor(sbp[0], nilfs); 318 if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) { 319 /* 320 * make the "clean" flag also to the opposite 321 * super block if both super blocks point to 322 * the same checkpoint. 323 */ 324 sbp[1]->s_state = sbp[0]->s_state; 325 flag = NILFS_SB_COMMIT_ALL; 326 } 327 ret = nilfs_commit_super(sb, flag); 328 } 329 return ret; 330 } 331 332 /** 333 * nilfs_move_2nd_super - relocate secondary super block 334 * @sb: super block instance 335 * @sb2off: new offset of the secondary super block (in bytes) 336 */ 337 static int nilfs_move_2nd_super(struct super_block *sb, loff_t sb2off) 338 { 339 struct the_nilfs *nilfs = sb->s_fs_info; 340 struct buffer_head *nsbh; 341 struct nilfs_super_block *nsbp; 342 sector_t blocknr, newblocknr; 343 unsigned long offset; 344 int sb2i; /* array index of the secondary superblock */ 345 int ret = 0; 346 347 /* nilfs->ns_sem must be locked by the caller. */ 348 if (nilfs->ns_sbh[1] && 349 nilfs->ns_sbh[1]->b_blocknr > nilfs->ns_first_data_block) { 350 sb2i = 1; 351 blocknr = nilfs->ns_sbh[1]->b_blocknr; 352 } else if (nilfs->ns_sbh[0]->b_blocknr > nilfs->ns_first_data_block) { 353 sb2i = 0; 354 blocknr = nilfs->ns_sbh[0]->b_blocknr; 355 } else { 356 sb2i = -1; 357 blocknr = 0; 358 } 359 if (sb2i >= 0 && (u64)blocknr << nilfs->ns_blocksize_bits == sb2off) 360 goto out; /* super block location is unchanged */ 361 362 /* Get new super block buffer */ 363 newblocknr = sb2off >> nilfs->ns_blocksize_bits; 364 offset = sb2off & (nilfs->ns_blocksize - 1); 365 nsbh = sb_getblk(sb, newblocknr); 366 if (!nsbh) { 367 nilfs_warn(sb, 368 "unable to move secondary superblock to block %llu", 369 (unsigned long long)newblocknr); 370 ret = -EIO; 371 goto out; 372 } 373 nsbp = (void *)nsbh->b_data + offset; 374 memset(nsbp, 0, nilfs->ns_blocksize); 375 376 if (sb2i >= 0) { 377 memcpy(nsbp, nilfs->ns_sbp[sb2i], nilfs->ns_sbsize); 378 brelse(nilfs->ns_sbh[sb2i]); 379 nilfs->ns_sbh[sb2i] = nsbh; 380 nilfs->ns_sbp[sb2i] = nsbp; 381 } else if (nilfs->ns_sbh[0]->b_blocknr < nilfs->ns_first_data_block) { 382 /* secondary super block will be restored to index 1 */ 383 nilfs->ns_sbh[1] = nsbh; 384 nilfs->ns_sbp[1] = nsbp; 385 } else { 386 brelse(nsbh); 387 } 388 out: 389 return ret; 390 } 391 392 /** 393 * nilfs_resize_fs - resize the filesystem 394 * @sb: super block instance 395 * @newsize: new size of the filesystem (in bytes) 396 */ 397 int nilfs_resize_fs(struct super_block *sb, __u64 newsize) 398 { 399 struct the_nilfs *nilfs = sb->s_fs_info; 400 struct nilfs_super_block **sbp; 401 __u64 devsize, newnsegs; 402 loff_t sb2off; 403 int ret; 404 405 ret = -ERANGE; 406 devsize = i_size_read(sb->s_bdev->bd_inode); 407 if (newsize > devsize) 408 goto out; 409 410 /* 411 * Write lock is required to protect some functions depending 412 * on the number of segments, the number of reserved segments, 413 * and so forth. 414 */ 415 down_write(&nilfs->ns_segctor_sem); 416 417 sb2off = NILFS_SB2_OFFSET_BYTES(newsize); 418 newnsegs = sb2off >> nilfs->ns_blocksize_bits; 419 do_div(newnsegs, nilfs->ns_blocks_per_segment); 420 421 ret = nilfs_sufile_resize(nilfs->ns_sufile, newnsegs); 422 up_write(&nilfs->ns_segctor_sem); 423 if (ret < 0) 424 goto out; 425 426 ret = nilfs_construct_segment(sb); 427 if (ret < 0) 428 goto out; 429 430 down_write(&nilfs->ns_sem); 431 nilfs_move_2nd_super(sb, sb2off); 432 ret = -EIO; 433 sbp = nilfs_prepare_super(sb, 0); 434 if (likely(sbp)) { 435 nilfs_set_log_cursor(sbp[0], nilfs); 436 /* 437 * Drop NILFS_RESIZE_FS flag for compatibility with 438 * mount-time resize which may be implemented in a 439 * future release. 440 */ 441 sbp[0]->s_state = cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & 442 ~NILFS_RESIZE_FS); 443 sbp[0]->s_dev_size = cpu_to_le64(newsize); 444 sbp[0]->s_nsegments = cpu_to_le64(nilfs->ns_nsegments); 445 if (sbp[1]) 446 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); 447 ret = nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); 448 } 449 up_write(&nilfs->ns_sem); 450 451 /* 452 * Reset the range of allocatable segments last. This order 453 * is important in the case of expansion because the secondary 454 * superblock must be protected from log write until migration 455 * completes. 456 */ 457 if (!ret) 458 nilfs_sufile_set_alloc_range(nilfs->ns_sufile, 0, newnsegs - 1); 459 out: 460 return ret; 461 } 462 463 static void nilfs_put_super(struct super_block *sb) 464 { 465 struct the_nilfs *nilfs = sb->s_fs_info; 466 467 nilfs_detach_log_writer(sb); 468 469 if (!sb_rdonly(sb)) { 470 down_write(&nilfs->ns_sem); 471 nilfs_cleanup_super(sb); 472 up_write(&nilfs->ns_sem); 473 } 474 475 iput(nilfs->ns_sufile); 476 iput(nilfs->ns_cpfile); 477 iput(nilfs->ns_dat); 478 479 destroy_nilfs(nilfs); 480 sb->s_fs_info = NULL; 481 } 482 483 static int nilfs_sync_fs(struct super_block *sb, int wait) 484 { 485 struct the_nilfs *nilfs = sb->s_fs_info; 486 struct nilfs_super_block **sbp; 487 int err = 0; 488 489 /* This function is called when super block should be written back */ 490 if (wait) 491 err = nilfs_construct_segment(sb); 492 493 down_write(&nilfs->ns_sem); 494 if (nilfs_sb_dirty(nilfs)) { 495 sbp = nilfs_prepare_super(sb, nilfs_sb_will_flip(nilfs)); 496 if (likely(sbp)) { 497 nilfs_set_log_cursor(sbp[0], nilfs); 498 nilfs_commit_super(sb, NILFS_SB_COMMIT); 499 } 500 } 501 up_write(&nilfs->ns_sem); 502 503 if (!err) 504 err = nilfs_flush_device(nilfs); 505 506 return err; 507 } 508 509 int nilfs_attach_checkpoint(struct super_block *sb, __u64 cno, int curr_mnt, 510 struct nilfs_root **rootp) 511 { 512 struct the_nilfs *nilfs = sb->s_fs_info; 513 struct nilfs_root *root; 514 struct nilfs_checkpoint *raw_cp; 515 struct buffer_head *bh_cp; 516 int err = -ENOMEM; 517 518 root = nilfs_find_or_create_root( 519 nilfs, curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno); 520 if (!root) 521 return err; 522 523 if (root->ifile) 524 goto reuse; /* already attached checkpoint */ 525 526 down_read(&nilfs->ns_segctor_sem); 527 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp, 528 &bh_cp); 529 up_read(&nilfs->ns_segctor_sem); 530 if (unlikely(err)) { 531 if (err == -ENOENT || err == -EINVAL) { 532 nilfs_err(sb, 533 "Invalid checkpoint (checkpoint number=%llu)", 534 (unsigned long long)cno); 535 err = -EINVAL; 536 } 537 goto failed; 538 } 539 540 err = nilfs_ifile_read(sb, root, nilfs->ns_inode_size, 541 &raw_cp->cp_ifile_inode, &root->ifile); 542 if (err) 543 goto failed_bh; 544 545 atomic64_set(&root->inodes_count, 546 le64_to_cpu(raw_cp->cp_inodes_count)); 547 atomic64_set(&root->blocks_count, 548 le64_to_cpu(raw_cp->cp_blocks_count)); 549 550 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp); 551 552 reuse: 553 *rootp = root; 554 return 0; 555 556 failed_bh: 557 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp); 558 failed: 559 nilfs_put_root(root); 560 561 return err; 562 } 563 564 static int nilfs_freeze(struct super_block *sb) 565 { 566 struct the_nilfs *nilfs = sb->s_fs_info; 567 int err; 568 569 if (sb_rdonly(sb)) 570 return 0; 571 572 /* Mark super block clean */ 573 down_write(&nilfs->ns_sem); 574 err = nilfs_cleanup_super(sb); 575 up_write(&nilfs->ns_sem); 576 return err; 577 } 578 579 static int nilfs_unfreeze(struct super_block *sb) 580 { 581 struct the_nilfs *nilfs = sb->s_fs_info; 582 583 if (sb_rdonly(sb)) 584 return 0; 585 586 down_write(&nilfs->ns_sem); 587 nilfs_setup_super(sb, false); 588 up_write(&nilfs->ns_sem); 589 return 0; 590 } 591 592 static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf) 593 { 594 struct super_block *sb = dentry->d_sb; 595 struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root; 596 struct the_nilfs *nilfs = root->nilfs; 597 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 598 unsigned long long blocks; 599 unsigned long overhead; 600 unsigned long nrsvblocks; 601 sector_t nfreeblocks; 602 u64 nmaxinodes, nfreeinodes; 603 int err; 604 605 /* 606 * Compute all of the segment blocks 607 * 608 * The blocks before first segment and after last segment 609 * are excluded. 610 */ 611 blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments 612 - nilfs->ns_first_data_block; 613 nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment; 614 615 /* 616 * Compute the overhead 617 * 618 * When distributing meta data blocks outside segment structure, 619 * We must count them as the overhead. 620 */ 621 overhead = 0; 622 623 err = nilfs_count_free_blocks(nilfs, &nfreeblocks); 624 if (unlikely(err)) 625 return err; 626 627 err = nilfs_ifile_count_free_inodes(root->ifile, 628 &nmaxinodes, &nfreeinodes); 629 if (unlikely(err)) { 630 nilfs_warn(sb, "failed to count free inodes: err=%d", err); 631 if (err == -ERANGE) { 632 /* 633 * If nilfs_palloc_count_max_entries() returns 634 * -ERANGE error code then we simply treat 635 * curent inodes count as maximum possible and 636 * zero as free inodes value. 637 */ 638 nmaxinodes = atomic64_read(&root->inodes_count); 639 nfreeinodes = 0; 640 err = 0; 641 } else 642 return err; 643 } 644 645 buf->f_type = NILFS_SUPER_MAGIC; 646 buf->f_bsize = sb->s_blocksize; 647 buf->f_blocks = blocks - overhead; 648 buf->f_bfree = nfreeblocks; 649 buf->f_bavail = (buf->f_bfree >= nrsvblocks) ? 650 (buf->f_bfree - nrsvblocks) : 0; 651 buf->f_files = nmaxinodes; 652 buf->f_ffree = nfreeinodes; 653 buf->f_namelen = NILFS_NAME_LEN; 654 buf->f_fsid.val[0] = (u32)id; 655 buf->f_fsid.val[1] = (u32)(id >> 32); 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_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 /* Shutting down log writer */ 1137 nilfs_detach_log_writer(sb); 1138 sb->s_flags |= SB_RDONLY; 1139 1140 /* 1141 * Remounting a valid RW partition RDONLY, so set 1142 * the RDONLY flag and then mark the partition as valid again. 1143 */ 1144 down_write(&nilfs->ns_sem); 1145 nilfs_cleanup_super(sb); 1146 up_write(&nilfs->ns_sem); 1147 } else { 1148 __u64 features; 1149 struct nilfs_root *root; 1150 1151 /* 1152 * Mounting a RDONLY partition read-write, so reread and 1153 * store the current valid flag. (It may have been changed 1154 * by fsck since we originally mounted the partition.) 1155 */ 1156 down_read(&nilfs->ns_sem); 1157 features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) & 1158 ~NILFS_FEATURE_COMPAT_RO_SUPP; 1159 up_read(&nilfs->ns_sem); 1160 if (features) { 1161 nilfs_warn(sb, 1162 "couldn't remount RDWR because of unsupported optional features (%llx)", 1163 (unsigned long long)features); 1164 err = -EROFS; 1165 goto restore_opts; 1166 } 1167 1168 sb->s_flags &= ~SB_RDONLY; 1169 1170 root = NILFS_I(d_inode(sb->s_root))->i_root; 1171 err = nilfs_attach_log_writer(sb, root); 1172 if (err) 1173 goto restore_opts; 1174 1175 down_write(&nilfs->ns_sem); 1176 nilfs_setup_super(sb, true); 1177 up_write(&nilfs->ns_sem); 1178 } 1179 out: 1180 return 0; 1181 1182 restore_opts: 1183 sb->s_flags = old_sb_flags; 1184 nilfs->ns_mount_opt = old_mount_opt; 1185 return err; 1186 } 1187 1188 struct nilfs_super_data { 1189 struct block_device *bdev; 1190 __u64 cno; 1191 int flags; 1192 }; 1193 1194 static int nilfs_parse_snapshot_option(const char *option, 1195 const substring_t *arg, 1196 struct nilfs_super_data *sd) 1197 { 1198 unsigned long long val; 1199 const char *msg = NULL; 1200 int err; 1201 1202 if (!(sd->flags & SB_RDONLY)) { 1203 msg = "read-only option is not specified"; 1204 goto parse_error; 1205 } 1206 1207 err = kstrtoull(arg->from, 0, &val); 1208 if (err) { 1209 if (err == -ERANGE) 1210 msg = "too large checkpoint number"; 1211 else 1212 msg = "malformed argument"; 1213 goto parse_error; 1214 } else if (val == 0) { 1215 msg = "invalid checkpoint number 0"; 1216 goto parse_error; 1217 } 1218 sd->cno = val; 1219 return 0; 1220 1221 parse_error: 1222 nilfs_err(NULL, "invalid option \"%s\": %s", option, msg); 1223 return 1; 1224 } 1225 1226 /** 1227 * nilfs_identify - pre-read mount options needed to identify mount instance 1228 * @data: mount options 1229 * @sd: nilfs_super_data 1230 */ 1231 static int nilfs_identify(char *data, struct nilfs_super_data *sd) 1232 { 1233 char *p, *options = data; 1234 substring_t args[MAX_OPT_ARGS]; 1235 int token; 1236 int ret = 0; 1237 1238 do { 1239 p = strsep(&options, ","); 1240 if (p != NULL && *p) { 1241 token = match_token(p, tokens, args); 1242 if (token == Opt_snapshot) 1243 ret = nilfs_parse_snapshot_option(p, &args[0], 1244 sd); 1245 } 1246 if (!options) 1247 break; 1248 BUG_ON(options == data); 1249 *(options - 1) = ','; 1250 } while (!ret); 1251 return ret; 1252 } 1253 1254 static int nilfs_set_bdev_super(struct super_block *s, void *data) 1255 { 1256 s->s_bdev = data; 1257 s->s_dev = s->s_bdev->bd_dev; 1258 return 0; 1259 } 1260 1261 static int nilfs_test_bdev_super(struct super_block *s, void *data) 1262 { 1263 return (void *)s->s_bdev == data; 1264 } 1265 1266 static struct dentry * 1267 nilfs_mount(struct file_system_type *fs_type, int flags, 1268 const char *dev_name, void *data) 1269 { 1270 struct nilfs_super_data sd; 1271 struct super_block *s; 1272 fmode_t mode = FMODE_READ | FMODE_EXCL; 1273 struct dentry *root_dentry; 1274 int err, s_new = false; 1275 1276 if (!(flags & SB_RDONLY)) 1277 mode |= FMODE_WRITE; 1278 1279 sd.bdev = blkdev_get_by_path(dev_name, mode, fs_type); 1280 if (IS_ERR(sd.bdev)) 1281 return ERR_CAST(sd.bdev); 1282 1283 sd.cno = 0; 1284 sd.flags = flags; 1285 if (nilfs_identify((char *)data, &sd)) { 1286 err = -EINVAL; 1287 goto failed; 1288 } 1289 1290 /* 1291 * once the super is inserted into the list by sget, s_umount 1292 * will protect the lockfs code from trying to start a snapshot 1293 * while we are mounting 1294 */ 1295 mutex_lock(&sd.bdev->bd_fsfreeze_mutex); 1296 if (sd.bdev->bd_fsfreeze_count > 0) { 1297 mutex_unlock(&sd.bdev->bd_fsfreeze_mutex); 1298 err = -EBUSY; 1299 goto failed; 1300 } 1301 s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, flags, 1302 sd.bdev); 1303 mutex_unlock(&sd.bdev->bd_fsfreeze_mutex); 1304 if (IS_ERR(s)) { 1305 err = PTR_ERR(s); 1306 goto failed; 1307 } 1308 1309 if (!s->s_root) { 1310 s_new = true; 1311 1312 /* New superblock instance created */ 1313 s->s_mode = mode; 1314 snprintf(s->s_id, sizeof(s->s_id), "%pg", sd.bdev); 1315 sb_set_blocksize(s, block_size(sd.bdev)); 1316 1317 err = nilfs_fill_super(s, data, flags & SB_SILENT ? 1 : 0); 1318 if (err) 1319 goto failed_super; 1320 1321 s->s_flags |= SB_ACTIVE; 1322 } else if (!sd.cno) { 1323 if (nilfs_tree_is_busy(s->s_root)) { 1324 if ((flags ^ s->s_flags) & SB_RDONLY) { 1325 nilfs_err(s, 1326 "the device already has a %s mount.", 1327 sb_rdonly(s) ? "read-only" : "read/write"); 1328 err = -EBUSY; 1329 goto failed_super; 1330 } 1331 } else { 1332 /* 1333 * Try remount to setup mount states if the current 1334 * tree is not mounted and only snapshots use this sb. 1335 */ 1336 err = nilfs_remount(s, &flags, data); 1337 if (err) 1338 goto failed_super; 1339 } 1340 } 1341 1342 if (sd.cno) { 1343 err = nilfs_attach_snapshot(s, sd.cno, &root_dentry); 1344 if (err) 1345 goto failed_super; 1346 } else { 1347 root_dentry = dget(s->s_root); 1348 } 1349 1350 if (!s_new) 1351 blkdev_put(sd.bdev, mode); 1352 1353 return root_dentry; 1354 1355 failed_super: 1356 deactivate_locked_super(s); 1357 1358 failed: 1359 if (!s_new) 1360 blkdev_put(sd.bdev, mode); 1361 return ERR_PTR(err); 1362 } 1363 1364 struct file_system_type nilfs_fs_type = { 1365 .owner = THIS_MODULE, 1366 .name = "nilfs2", 1367 .mount = nilfs_mount, 1368 .kill_sb = kill_block_super, 1369 .fs_flags = FS_REQUIRES_DEV, 1370 }; 1371 MODULE_ALIAS_FS("nilfs2"); 1372 1373 static void nilfs_inode_init_once(void *obj) 1374 { 1375 struct nilfs_inode_info *ii = obj; 1376 1377 INIT_LIST_HEAD(&ii->i_dirty); 1378 #ifdef CONFIG_NILFS_XATTR 1379 init_rwsem(&ii->xattr_sem); 1380 #endif 1381 address_space_init_once(&ii->i_btnode_cache); 1382 ii->i_bmap = &ii->i_bmap_data; 1383 inode_init_once(&ii->vfs_inode); 1384 } 1385 1386 static void nilfs_segbuf_init_once(void *obj) 1387 { 1388 memset(obj, 0, sizeof(struct nilfs_segment_buffer)); 1389 } 1390 1391 static void nilfs_destroy_cachep(void) 1392 { 1393 /* 1394 * Make sure all delayed rcu free inodes are flushed before we 1395 * destroy cache. 1396 */ 1397 rcu_barrier(); 1398 1399 kmem_cache_destroy(nilfs_inode_cachep); 1400 kmem_cache_destroy(nilfs_transaction_cachep); 1401 kmem_cache_destroy(nilfs_segbuf_cachep); 1402 kmem_cache_destroy(nilfs_btree_path_cache); 1403 } 1404 1405 static int __init nilfs_init_cachep(void) 1406 { 1407 nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache", 1408 sizeof(struct nilfs_inode_info), 0, 1409 SLAB_RECLAIM_ACCOUNT|SLAB_ACCOUNT, 1410 nilfs_inode_init_once); 1411 if (!nilfs_inode_cachep) 1412 goto fail; 1413 1414 nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache", 1415 sizeof(struct nilfs_transaction_info), 0, 1416 SLAB_RECLAIM_ACCOUNT, NULL); 1417 if (!nilfs_transaction_cachep) 1418 goto fail; 1419 1420 nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache", 1421 sizeof(struct nilfs_segment_buffer), 0, 1422 SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once); 1423 if (!nilfs_segbuf_cachep) 1424 goto fail; 1425 1426 nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache", 1427 sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX, 1428 0, 0, NULL); 1429 if (!nilfs_btree_path_cache) 1430 goto fail; 1431 1432 return 0; 1433 1434 fail: 1435 nilfs_destroy_cachep(); 1436 return -ENOMEM; 1437 } 1438 1439 static int __init init_nilfs_fs(void) 1440 { 1441 int err; 1442 1443 err = nilfs_init_cachep(); 1444 if (err) 1445 goto fail; 1446 1447 err = nilfs_sysfs_init(); 1448 if (err) 1449 goto free_cachep; 1450 1451 err = register_filesystem(&nilfs_fs_type); 1452 if (err) 1453 goto deinit_sysfs_entry; 1454 1455 printk(KERN_INFO "NILFS version 2 loaded\n"); 1456 return 0; 1457 1458 deinit_sysfs_entry: 1459 nilfs_sysfs_exit(); 1460 free_cachep: 1461 nilfs_destroy_cachep(); 1462 fail: 1463 return err; 1464 } 1465 1466 static void __exit exit_nilfs_fs(void) 1467 { 1468 nilfs_destroy_cachep(); 1469 nilfs_sysfs_exit(); 1470 unregister_filesystem(&nilfs_fs_type); 1471 } 1472 1473 module_init(init_nilfs_fs) 1474 module_exit(exit_nilfs_fs) 1475