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 <linux/fs_context.h> 39#include "nilfs.h" 40#include "export.h" 41#include "mdt.h" 42#include "alloc.h" 43#include "btree.h" 44#include "btnode.h" 45#include "page.h" 46#include "cpfile.h" 47#include "sufile.h" /* nilfs_sufile_resize(), nilfs_sufile_set_alloc_range() */ 48#include "ifile.h" 49#include "dat.h" 50#include "segment.h" 51#include "segbuf.h" 52 53MODULE_AUTHOR("NTT Corp."); 54MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem " 55 "(NILFS)"); 56MODULE_LICENSE("GPL"); 57 58static struct kmem_cache *nilfs_inode_cachep; 59struct kmem_cache *nilfs_transaction_cachep; 60struct kmem_cache *nilfs_segbuf_cachep; 61struct kmem_cache *nilfs_btree_path_cache; 62 63static int nilfs_setup_super(struct super_block *sb, int is_mount); 64static int nilfs_remount(struct super_block *sb, int *flags, char *data); 65 66void __nilfs_msg(struct super_block *sb, const char *fmt, ...) 67{ 68 struct va_format vaf; 69 va_list args; 70 int level; 71 72 va_start(args, fmt); 73 74 level = printk_get_level(fmt); 75 vaf.fmt = printk_skip_level(fmt); 76 vaf.va = &args; 77 78 if (sb) 79 printk("%c%cNILFS (%s): %pV\n", 80 KERN_SOH_ASCII, level, sb->s_id, &vaf); 81 else 82 printk("%c%cNILFS: %pV\n", 83 KERN_SOH_ASCII, level, &vaf); 84 85 va_end(args); 86} 87 88static void nilfs_set_error(struct super_block *sb) 89{ 90 struct the_nilfs *nilfs = sb->s_fs_info; 91 struct nilfs_super_block **sbp; 92 93 down_write(&nilfs->ns_sem); 94 if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) { 95 nilfs->ns_mount_state |= NILFS_ERROR_FS; 96 sbp = nilfs_prepare_super(sb, 0); 97 if (likely(sbp)) { 98 sbp[0]->s_state |= cpu_to_le16(NILFS_ERROR_FS); 99 if (sbp[1]) 100 sbp[1]->s_state |= cpu_to_le16(NILFS_ERROR_FS); 101 nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); 102 } 103 } 104 up_write(&nilfs->ns_sem); 105} 106 107/** 108 * __nilfs_error() - report failure condition on a filesystem 109 * 110 * __nilfs_error() sets an ERROR_FS flag on the superblock as well as 111 * reporting an error message. This function should be called when 112 * NILFS detects incoherences or defects of meta data on disk. 113 * 114 * This implements the body of nilfs_error() macro. Normally, 115 * nilfs_error() should be used. As for sustainable errors such as a 116 * single-shot I/O error, nilfs_err() should be used instead. 117 * 118 * Callers should not add a trailing newline since this will do it. 119 */ 120void __nilfs_error(struct super_block *sb, const char *function, 121 const char *fmt, ...) 122{ 123 struct the_nilfs *nilfs = sb->s_fs_info; 124 struct va_format vaf; 125 va_list args; 126 127 va_start(args, fmt); 128 129 vaf.fmt = fmt; 130 vaf.va = &args; 131 132 printk(KERN_CRIT "NILFS error (device %s): %s: %pV\n", 133 sb->s_id, function, &vaf); 134 135 va_end(args); 136 137 if (!sb_rdonly(sb)) { 138 nilfs_set_error(sb); 139 140 if (nilfs_test_opt(nilfs, ERRORS_RO)) { 141 printk(KERN_CRIT "Remounting filesystem read-only\n"); 142 sb->s_flags |= SB_RDONLY; 143 } 144 } 145 146 if (nilfs_test_opt(nilfs, ERRORS_PANIC)) 147 panic("NILFS (device %s): panic forced after error\n", 148 sb->s_id); 149} 150 151struct inode *nilfs_alloc_inode(struct super_block *sb) 152{ 153 struct nilfs_inode_info *ii; 154 155 ii = alloc_inode_sb(sb, nilfs_inode_cachep, GFP_NOFS); 156 if (!ii) 157 return NULL; 158 ii->i_bh = NULL; 159 ii->i_state = 0; 160 ii->i_cno = 0; 161 ii->i_assoc_inode = NULL; 162 ii->i_bmap = &ii->i_bmap_data; 163 return &ii->vfs_inode; 164} 165 166static void nilfs_free_inode(struct inode *inode) 167{ 168 if (nilfs_is_metadata_file_inode(inode)) 169 nilfs_mdt_destroy(inode); 170 171 kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode)); 172} 173 174static int nilfs_sync_super(struct super_block *sb, int flag) 175{ 176 struct the_nilfs *nilfs = sb->s_fs_info; 177 int err; 178 179 retry: 180 set_buffer_dirty(nilfs->ns_sbh[0]); 181 if (nilfs_test_opt(nilfs, BARRIER)) { 182 err = __sync_dirty_buffer(nilfs->ns_sbh[0], 183 REQ_SYNC | REQ_PREFLUSH | REQ_FUA); 184 } else { 185 err = sync_dirty_buffer(nilfs->ns_sbh[0]); 186 } 187 188 if (unlikely(err)) { 189 nilfs_err(sb, "unable to write superblock: err=%d", err); 190 if (err == -EIO && nilfs->ns_sbh[1]) { 191 /* 192 * sbp[0] points to newer log than sbp[1], 193 * so copy sbp[0] to sbp[1] to take over sbp[0]. 194 */ 195 memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0], 196 nilfs->ns_sbsize); 197 nilfs_fall_back_super_block(nilfs); 198 goto retry; 199 } 200 } else { 201 struct nilfs_super_block *sbp = nilfs->ns_sbp[0]; 202 203 nilfs->ns_sbwcount++; 204 205 /* 206 * The latest segment becomes trailable from the position 207 * written in superblock. 208 */ 209 clear_nilfs_discontinued(nilfs); 210 211 /* update GC protection for recent segments */ 212 if (nilfs->ns_sbh[1]) { 213 if (flag == NILFS_SB_COMMIT_ALL) { 214 set_buffer_dirty(nilfs->ns_sbh[1]); 215 if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0) 216 goto out; 217 } 218 if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) < 219 le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno)) 220 sbp = nilfs->ns_sbp[1]; 221 } 222 223 spin_lock(&nilfs->ns_last_segment_lock); 224 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq); 225 spin_unlock(&nilfs->ns_last_segment_lock); 226 } 227 out: 228 return err; 229} 230 231void nilfs_set_log_cursor(struct nilfs_super_block *sbp, 232 struct the_nilfs *nilfs) 233{ 234 sector_t nfreeblocks; 235 236 /* nilfs->ns_sem must be locked by the caller. */ 237 nilfs_count_free_blocks(nilfs, &nfreeblocks); 238 sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks); 239 240 spin_lock(&nilfs->ns_last_segment_lock); 241 sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq); 242 sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg); 243 sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno); 244 spin_unlock(&nilfs->ns_last_segment_lock); 245} 246 247struct nilfs_super_block **nilfs_prepare_super(struct super_block *sb, 248 int flip) 249{ 250 struct the_nilfs *nilfs = sb->s_fs_info; 251 struct nilfs_super_block **sbp = nilfs->ns_sbp; 252 253 /* nilfs->ns_sem must be locked by the caller. */ 254 if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) { 255 if (sbp[1] && 256 sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) { 257 memcpy(sbp[0], sbp[1], nilfs->ns_sbsize); 258 } else { 259 nilfs_crit(sb, "superblock broke"); 260 return NULL; 261 } 262 } else if (sbp[1] && 263 sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) { 264 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); 265 } 266 267 if (flip && sbp[1]) 268 nilfs_swap_super_block(nilfs); 269 270 return sbp; 271} 272 273int nilfs_commit_super(struct super_block *sb, int flag) 274{ 275 struct the_nilfs *nilfs = sb->s_fs_info; 276 struct nilfs_super_block **sbp = nilfs->ns_sbp; 277 time64_t t; 278 279 /* nilfs->ns_sem must be locked by the caller. */ 280 t = ktime_get_real_seconds(); 281 nilfs->ns_sbwtime = t; 282 sbp[0]->s_wtime = cpu_to_le64(t); 283 sbp[0]->s_sum = 0; 284 sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed, 285 (unsigned char *)sbp[0], 286 nilfs->ns_sbsize)); 287 if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) { 288 sbp[1]->s_wtime = sbp[0]->s_wtime; 289 sbp[1]->s_sum = 0; 290 sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed, 291 (unsigned char *)sbp[1], 292 nilfs->ns_sbsize)); 293 } 294 clear_nilfs_sb_dirty(nilfs); 295 nilfs->ns_flushed_device = 1; 296 /* make sure store to ns_flushed_device cannot be reordered */ 297 smp_wmb(); 298 return nilfs_sync_super(sb, flag); 299} 300 301/** 302 * nilfs_cleanup_super() - write filesystem state for cleanup 303 * @sb: super block instance to be unmounted or degraded to read-only 304 * 305 * This function restores state flags in the on-disk super block. 306 * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the 307 * filesystem was not clean previously. 308 */ 309int nilfs_cleanup_super(struct super_block *sb) 310{ 311 struct the_nilfs *nilfs = sb->s_fs_info; 312 struct nilfs_super_block **sbp; 313 int flag = NILFS_SB_COMMIT; 314 int ret = -EIO; 315 316 sbp = nilfs_prepare_super(sb, 0); 317 if (sbp) { 318 sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state); 319 nilfs_set_log_cursor(sbp[0], nilfs); 320 if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) { 321 /* 322 * make the "clean" flag also to the opposite 323 * super block if both super blocks point to 324 * the same checkpoint. 325 */ 326 sbp[1]->s_state = sbp[0]->s_state; 327 flag = NILFS_SB_COMMIT_ALL; 328 } 329 ret = nilfs_commit_super(sb, flag); 330 } 331 return ret; 332} 333 334/** 335 * nilfs_move_2nd_super - relocate secondary super block 336 * @sb: super block instance 337 * @sb2off: new offset of the secondary super block (in bytes) 338 */ 339static int nilfs_move_2nd_super(struct super_block *sb, loff_t sb2off) 340{ 341 struct the_nilfs *nilfs = sb->s_fs_info; 342 struct buffer_head *nsbh; 343 struct nilfs_super_block *nsbp; 344 sector_t blocknr, newblocknr; 345 unsigned long offset; 346 int sb2i; /* array index of the secondary superblock */ 347 int ret = 0; 348 349 /* nilfs->ns_sem must be locked by the caller. */ 350 if (nilfs->ns_sbh[1] && 351 nilfs->ns_sbh[1]->b_blocknr > nilfs->ns_first_data_block) { 352 sb2i = 1; 353 blocknr = nilfs->ns_sbh[1]->b_blocknr; 354 } else if (nilfs->ns_sbh[0]->b_blocknr > nilfs->ns_first_data_block) { 355 sb2i = 0; 356 blocknr = nilfs->ns_sbh[0]->b_blocknr; 357 } else { 358 sb2i = -1; 359 blocknr = 0; 360 } 361 if (sb2i >= 0 && (u64)blocknr << nilfs->ns_blocksize_bits == sb2off) 362 goto out; /* super block location is unchanged */ 363 364 /* Get new super block buffer */ 365 newblocknr = sb2off >> nilfs->ns_blocksize_bits; 366 offset = sb2off & (nilfs->ns_blocksize - 1); 367 nsbh = sb_getblk(sb, newblocknr); 368 if (!nsbh) { 369 nilfs_warn(sb, 370 "unable to move secondary superblock to block %llu", 371 (unsigned long long)newblocknr); 372 ret = -EIO; 373 goto out; 374 } 375 nsbp = (void *)nsbh->b_data + offset; 376 377 lock_buffer(nsbh); 378 if (sb2i >= 0) { 379 /* 380 * The position of the second superblock only changes by 4KiB, 381 * which is larger than the maximum superblock data size 382 * (= 1KiB), so there is no need to use memmove() to allow 383 * overlap between source and destination. 384 */ 385 memcpy(nsbp, nilfs->ns_sbp[sb2i], nilfs->ns_sbsize); 386 387 /* 388 * Zero fill after copy to avoid overwriting in case of move 389 * within the same block. 390 */ 391 memset(nsbh->b_data, 0, offset); 392 memset((void *)nsbp + nilfs->ns_sbsize, 0, 393 nsbh->b_size - offset - nilfs->ns_sbsize); 394 } else { 395 memset(nsbh->b_data, 0, nsbh->b_size); 396 } 397 set_buffer_uptodate(nsbh); 398 unlock_buffer(nsbh); 399 400 if (sb2i >= 0) { 401 brelse(nilfs->ns_sbh[sb2i]); 402 nilfs->ns_sbh[sb2i] = nsbh; 403 nilfs->ns_sbp[sb2i] = nsbp; 404 } else if (nilfs->ns_sbh[0]->b_blocknr < nilfs->ns_first_data_block) { 405 /* secondary super block will be restored to index 1 */ 406 nilfs->ns_sbh[1] = nsbh; 407 nilfs->ns_sbp[1] = nsbp; 408 } else { 409 brelse(nsbh); 410 } 411out: 412 return ret; 413} 414 415/** 416 * nilfs_resize_fs - resize the filesystem 417 * @sb: super block instance 418 * @newsize: new size of the filesystem (in bytes) 419 */ 420int nilfs_resize_fs(struct super_block *sb, __u64 newsize) 421{ 422 struct the_nilfs *nilfs = sb->s_fs_info; 423 struct nilfs_super_block **sbp; 424 __u64 devsize, newnsegs; 425 loff_t sb2off; 426 int ret; 427 428 ret = -ERANGE; 429 devsize = bdev_nr_bytes(sb->s_bdev); 430 if (newsize > devsize) 431 goto out; 432 433 /* 434 * Prevent underflow in second superblock position calculation. 435 * The exact minimum size check is done in nilfs_sufile_resize(). 436 */ 437 if (newsize < 4096) { 438 ret = -ENOSPC; 439 goto out; 440 } 441 442 /* 443 * Write lock is required to protect some functions depending 444 * on the number of segments, the number of reserved segments, 445 * and so forth. 446 */ 447 down_write(&nilfs->ns_segctor_sem); 448 449 sb2off = NILFS_SB2_OFFSET_BYTES(newsize); 450 newnsegs = sb2off >> nilfs->ns_blocksize_bits; 451 do_div(newnsegs, nilfs->ns_blocks_per_segment); 452 453 ret = nilfs_sufile_resize(nilfs->ns_sufile, newnsegs); 454 up_write(&nilfs->ns_segctor_sem); 455 if (ret < 0) 456 goto out; 457 458 ret = nilfs_construct_segment(sb); 459 if (ret < 0) 460 goto out; 461 462 down_write(&nilfs->ns_sem); 463 nilfs_move_2nd_super(sb, sb2off); 464 ret = -EIO; 465 sbp = nilfs_prepare_super(sb, 0); 466 if (likely(sbp)) { 467 nilfs_set_log_cursor(sbp[0], nilfs); 468 /* 469 * Drop NILFS_RESIZE_FS flag for compatibility with 470 * mount-time resize which may be implemented in a 471 * future release. 472 */ 473 sbp[0]->s_state = cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & 474 ~NILFS_RESIZE_FS); 475 sbp[0]->s_dev_size = cpu_to_le64(newsize); 476 sbp[0]->s_nsegments = cpu_to_le64(nilfs->ns_nsegments); 477 if (sbp[1]) 478 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); 479 ret = nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); 480 } 481 up_write(&nilfs->ns_sem); 482 483 /* 484 * Reset the range of allocatable segments last. This order 485 * is important in the case of expansion because the secondary 486 * superblock must be protected from log write until migration 487 * completes. 488 */ 489 if (!ret) 490 nilfs_sufile_set_alloc_range(nilfs->ns_sufile, 0, newnsegs - 1); 491out: 492 return ret; 493} 494 495static void nilfs_put_super(struct super_block *sb) 496{ 497 struct the_nilfs *nilfs = sb->s_fs_info; 498 499 nilfs_detach_log_writer(sb); 500 501 if (!sb_rdonly(sb)) { 502 down_write(&nilfs->ns_sem); 503 nilfs_cleanup_super(sb); 504 up_write(&nilfs->ns_sem); 505 } 506 507 nilfs_sysfs_delete_device_group(nilfs); 508 iput(nilfs->ns_sufile); 509 iput(nilfs->ns_cpfile); 510 iput(nilfs->ns_dat); 511 512 destroy_nilfs(nilfs); 513 sb->s_fs_info = NULL; 514} 515 516static int nilfs_sync_fs(struct super_block *sb, int wait) 517{ 518 struct the_nilfs *nilfs = sb->s_fs_info; 519 struct nilfs_super_block **sbp; 520 int err = 0; 521 522 /* This function is called when super block should be written back */ 523 if (wait) 524 err = nilfs_construct_segment(sb); 525 526 down_write(&nilfs->ns_sem); 527 if (nilfs_sb_dirty(nilfs)) { 528 sbp = nilfs_prepare_super(sb, nilfs_sb_will_flip(nilfs)); 529 if (likely(sbp)) { 530 nilfs_set_log_cursor(sbp[0], nilfs); 531 nilfs_commit_super(sb, NILFS_SB_COMMIT); 532 } 533 } 534 up_write(&nilfs->ns_sem); 535 536 if (!err) 537 err = nilfs_flush_device(nilfs); 538 539 return err; 540} 541 542int nilfs_attach_checkpoint(struct super_block *sb, __u64 cno, int curr_mnt, 543 struct nilfs_root **rootp) 544{ 545 struct the_nilfs *nilfs = sb->s_fs_info; 546 struct nilfs_root *root; 547 struct nilfs_checkpoint *raw_cp; 548 struct buffer_head *bh_cp; 549 int err = -ENOMEM; 550 551 root = nilfs_find_or_create_root( 552 nilfs, curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno); 553 if (!root) 554 return err; 555 556 if (root->ifile) 557 goto reuse; /* already attached checkpoint */ 558 559 down_read(&nilfs->ns_segctor_sem); 560 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp, 561 &bh_cp); 562 up_read(&nilfs->ns_segctor_sem); 563 if (unlikely(err)) { 564 if (err == -ENOENT || err == -EINVAL) { 565 nilfs_err(sb, 566 "Invalid checkpoint (checkpoint number=%llu)", 567 (unsigned long long)cno); 568 err = -EINVAL; 569 } 570 goto failed; 571 } 572 573 err = nilfs_ifile_read(sb, root, nilfs->ns_inode_size, 574 &raw_cp->cp_ifile_inode, &root->ifile); 575 if (err) 576 goto failed_bh; 577 578 atomic64_set(&root->inodes_count, 579 le64_to_cpu(raw_cp->cp_inodes_count)); 580 atomic64_set(&root->blocks_count, 581 le64_to_cpu(raw_cp->cp_blocks_count)); 582 583 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp); 584 585 reuse: 586 *rootp = root; 587 return 0; 588 589 failed_bh: 590 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp); 591 failed: 592 nilfs_put_root(root); 593 594 return err; 595} 596 597static int nilfs_freeze(struct super_block *sb) 598{ 599 struct the_nilfs *nilfs = sb->s_fs_info; 600 int err; 601 602 if (sb_rdonly(sb)) 603 return 0; 604 605 /* Mark super block clean */ 606 down_write(&nilfs->ns_sem); 607 err = nilfs_cleanup_super(sb); 608 up_write(&nilfs->ns_sem); 609 return err; 610} 611 612static int nilfs_unfreeze(struct super_block *sb) 613{ 614 struct the_nilfs *nilfs = sb->s_fs_info; 615 616 if (sb_rdonly(sb)) 617 return 0; 618 619 down_write(&nilfs->ns_sem); 620 nilfs_setup_super(sb, false); 621 up_write(&nilfs->ns_sem); 622 return 0; 623} 624 625static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf) 626{ 627 struct super_block *sb = dentry->d_sb; 628 struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root; 629 struct the_nilfs *nilfs = root->nilfs; 630 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 631 unsigned long long blocks; 632 unsigned long overhead; 633 unsigned long nrsvblocks; 634 sector_t nfreeblocks; 635 u64 nmaxinodes, nfreeinodes; 636 int err; 637 638 /* 639 * Compute all of the segment blocks 640 * 641 * The blocks before first segment and after last segment 642 * are excluded. 643 */ 644 blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments 645 - nilfs->ns_first_data_block; 646 nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment; 647 648 /* 649 * Compute the overhead 650 * 651 * When distributing meta data blocks outside segment structure, 652 * We must count them as the overhead. 653 */ 654 overhead = 0; 655 656 err = nilfs_count_free_blocks(nilfs, &nfreeblocks); 657 if (unlikely(err)) 658 return err; 659 660 err = nilfs_ifile_count_free_inodes(root->ifile, 661 &nmaxinodes, &nfreeinodes); 662 if (unlikely(err)) { 663 nilfs_warn(sb, "failed to count free inodes: err=%d", err); 664 if (err == -ERANGE) { 665 /* 666 * If nilfs_palloc_count_max_entries() returns 667 * -ERANGE error code then we simply treat 668 * curent inodes count as maximum possible and 669 * zero as free inodes value. 670 */ 671 nmaxinodes = atomic64_read(&root->inodes_count); 672 nfreeinodes = 0; 673 err = 0; 674 } else 675 return err; 676 } 677 678 buf->f_type = NILFS_SUPER_MAGIC; 679 buf->f_bsize = sb->s_blocksize; 680 buf->f_blocks = blocks - overhead; 681 buf->f_bfree = nfreeblocks; 682 buf->f_bavail = (buf->f_bfree >= nrsvblocks) ? 683 (buf->f_bfree - nrsvblocks) : 0; 684 buf->f_files = nmaxinodes; 685 buf->f_ffree = nfreeinodes; 686 buf->f_namelen = NILFS_NAME_LEN; 687 buf->f_fsid = u64_to_fsid(id); 688 689 return 0; 690} 691 692static int nilfs_show_options(struct seq_file *seq, struct dentry *dentry) 693{ 694 struct super_block *sb = dentry->d_sb; 695 struct the_nilfs *nilfs = sb->s_fs_info; 696 struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root; 697 698 if (!nilfs_test_opt(nilfs, BARRIER)) 699 seq_puts(seq, ",nobarrier"); 700 if (root->cno != NILFS_CPTREE_CURRENT_CNO) 701 seq_printf(seq, ",cp=%llu", (unsigned long long)root->cno); 702 if (nilfs_test_opt(nilfs, ERRORS_PANIC)) 703 seq_puts(seq, ",errors=panic"); 704 if (nilfs_test_opt(nilfs, ERRORS_CONT)) 705 seq_puts(seq, ",errors=continue"); 706 if (nilfs_test_opt(nilfs, STRICT_ORDER)) 707 seq_puts(seq, ",order=strict"); 708 if (nilfs_test_opt(nilfs, NORECOVERY)) 709 seq_puts(seq, ",norecovery"); 710 if (nilfs_test_opt(nilfs, DISCARD)) 711 seq_puts(seq, ",discard"); 712 713 return 0; 714} 715 716static const struct super_operations nilfs_sops = { 717 .alloc_inode = nilfs_alloc_inode, 718 .free_inode = nilfs_free_inode, 719 .dirty_inode = nilfs_dirty_inode, 720 .evict_inode = nilfs_evict_inode, 721 .put_super = nilfs_put_super, 722 .sync_fs = nilfs_sync_fs, 723 .freeze_fs = nilfs_freeze, 724 .unfreeze_fs = nilfs_unfreeze, 725 .statfs = nilfs_statfs, 726 .remount_fs = nilfs_remount, 727 .show_options = nilfs_show_options 728}; 729 730enum { 731 Opt_err_cont, Opt_err_panic, Opt_err_ro, 732 Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery, 733 Opt_discard, Opt_nodiscard, Opt_err, 734}; 735 736static match_table_t tokens = { 737 {Opt_err_cont, "errors=continue"}, 738 {Opt_err_panic, "errors=panic"}, 739 {Opt_err_ro, "errors=remount-ro"}, 740 {Opt_barrier, "barrier"}, 741 {Opt_nobarrier, "nobarrier"}, 742 {Opt_snapshot, "cp=%u"}, 743 {Opt_order, "order=%s"}, 744 {Opt_norecovery, "norecovery"}, 745 {Opt_discard, "discard"}, 746 {Opt_nodiscard, "nodiscard"}, 747 {Opt_err, NULL} 748}; 749 750static int parse_options(char *options, struct super_block *sb, int is_remount) 751{ 752 struct the_nilfs *nilfs = sb->s_fs_info; 753 char *p; 754 substring_t args[MAX_OPT_ARGS]; 755 756 if (!options) 757 return 1; 758 759 while ((p = strsep(&options, ",")) != NULL) { 760 int token; 761 762 if (!*p) 763 continue; 764 765 token = match_token(p, tokens, args); 766 switch (token) { 767 case Opt_barrier: 768 nilfs_set_opt(nilfs, BARRIER); 769 break; 770 case Opt_nobarrier: 771 nilfs_clear_opt(nilfs, BARRIER); 772 break; 773 case Opt_order: 774 if (strcmp(args[0].from, "relaxed") == 0) 775 /* Ordered data semantics */ 776 nilfs_clear_opt(nilfs, STRICT_ORDER); 777 else if (strcmp(args[0].from, "strict") == 0) 778 /* Strict in-order semantics */ 779 nilfs_set_opt(nilfs, STRICT_ORDER); 780 else 781 return 0; 782 break; 783 case Opt_err_panic: 784 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_PANIC); 785 break; 786 case Opt_err_ro: 787 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_RO); 788 break; 789 case Opt_err_cont: 790 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_CONT); 791 break; 792 case Opt_snapshot: 793 if (is_remount) { 794 nilfs_err(sb, 795 "\"%s\" option is invalid for remount", 796 p); 797 return 0; 798 } 799 break; 800 case Opt_norecovery: 801 nilfs_set_opt(nilfs, NORECOVERY); 802 break; 803 case Opt_discard: 804 nilfs_set_opt(nilfs, DISCARD); 805 break; 806 case Opt_nodiscard: 807 nilfs_clear_opt(nilfs, DISCARD); 808 break; 809 default: 810 nilfs_err(sb, "unrecognized mount option \"%s\"", p); 811 return 0; 812 } 813 } 814 return 1; 815} 816 817static inline void 818nilfs_set_default_options(struct super_block *sb, 819 struct nilfs_super_block *sbp) 820{ 821 struct the_nilfs *nilfs = sb->s_fs_info; 822 823 nilfs->ns_mount_opt = 824 NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER; 825} 826 827static int nilfs_setup_super(struct super_block *sb, int is_mount) 828{ 829 struct the_nilfs *nilfs = sb->s_fs_info; 830 struct nilfs_super_block **sbp; 831 int max_mnt_count; 832 int mnt_count; 833 834 /* nilfs->ns_sem must be locked by the caller. */ 835 sbp = nilfs_prepare_super(sb, 0); 836 if (!sbp) 837 return -EIO; 838 839 if (!is_mount) 840 goto skip_mount_setup; 841 842 max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count); 843 mnt_count = le16_to_cpu(sbp[0]->s_mnt_count); 844 845 if (nilfs->ns_mount_state & NILFS_ERROR_FS) { 846 nilfs_warn(sb, "mounting fs with errors"); 847#if 0 848 } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) { 849 nilfs_warn(sb, "maximal mount count reached"); 850#endif 851 } 852 if (!max_mnt_count) 853 sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT); 854 855 sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1); 856 sbp[0]->s_mtime = cpu_to_le64(ktime_get_real_seconds()); 857 858skip_mount_setup: 859 sbp[0]->s_state = 860 cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS); 861 /* synchronize sbp[1] with sbp[0] */ 862 if (sbp[1]) 863 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); 864 return nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); 865} 866 867struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb, 868 u64 pos, int blocksize, 869 struct buffer_head **pbh) 870{ 871 unsigned long long sb_index = pos; 872 unsigned long offset; 873 874 offset = do_div(sb_index, blocksize); 875 *pbh = sb_bread(sb, sb_index); 876 if (!*pbh) 877 return NULL; 878 return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset); 879} 880 881int nilfs_store_magic_and_option(struct super_block *sb, 882 struct nilfs_super_block *sbp, 883 char *data) 884{ 885 struct the_nilfs *nilfs = sb->s_fs_info; 886 887 sb->s_magic = le16_to_cpu(sbp->s_magic); 888 889 /* FS independent flags */ 890#ifdef NILFS_ATIME_DISABLE 891 sb->s_flags |= SB_NOATIME; 892#endif 893 894 nilfs_set_default_options(sb, sbp); 895 896 nilfs->ns_resuid = le16_to_cpu(sbp->s_def_resuid); 897 nilfs->ns_resgid = le16_to_cpu(sbp->s_def_resgid); 898 nilfs->ns_interval = le32_to_cpu(sbp->s_c_interval); 899 nilfs->ns_watermark = le32_to_cpu(sbp->s_c_block_max); 900 901 return !parse_options(data, sb, 0) ? -EINVAL : 0; 902} 903 904int nilfs_check_feature_compatibility(struct super_block *sb, 905 struct nilfs_super_block *sbp) 906{ 907 __u64 features; 908 909 features = le64_to_cpu(sbp->s_feature_incompat) & 910 ~NILFS_FEATURE_INCOMPAT_SUPP; 911 if (features) { 912 nilfs_err(sb, 913 "couldn't mount because of unsupported optional features (%llx)", 914 (unsigned long long)features); 915 return -EINVAL; 916 } 917 features = le64_to_cpu(sbp->s_feature_compat_ro) & 918 ~NILFS_FEATURE_COMPAT_RO_SUPP; 919 if (!sb_rdonly(sb) && features) { 920 nilfs_err(sb, 921 "couldn't mount RDWR because of unsupported optional features (%llx)", 922 (unsigned long long)features); 923 return -EINVAL; 924 } 925 return 0; 926} 927 928static int nilfs_get_root_dentry(struct super_block *sb, 929 struct nilfs_root *root, 930 struct dentry **root_dentry) 931{ 932 struct inode *inode; 933 struct dentry *dentry; 934 int ret = 0; 935 936 inode = nilfs_iget(sb, root, NILFS_ROOT_INO); 937 if (IS_ERR(inode)) { 938 ret = PTR_ERR(inode); 939 nilfs_err(sb, "error %d getting root inode", ret); 940 goto out; 941 } 942 if (!S_ISDIR(inode->i_mode) || !inode->i_blocks || !inode->i_size) { 943 iput(inode); 944 nilfs_err(sb, "corrupt root inode"); 945 ret = -EINVAL; 946 goto out; 947 } 948 949 if (root->cno == NILFS_CPTREE_CURRENT_CNO) { 950 dentry = d_find_alias(inode); 951 if (!dentry) { 952 dentry = d_make_root(inode); 953 if (!dentry) { 954 ret = -ENOMEM; 955 goto failed_dentry; 956 } 957 } else { 958 iput(inode); 959 } 960 } else { 961 dentry = d_obtain_root(inode); 962 if (IS_ERR(dentry)) { 963 ret = PTR_ERR(dentry); 964 goto failed_dentry; 965 } 966 } 967 *root_dentry = dentry; 968 out: 969 return ret; 970 971 failed_dentry: 972 nilfs_err(sb, "error %d getting root dentry", ret); 973 goto out; 974} 975 976static int nilfs_attach_snapshot(struct super_block *s, __u64 cno, 977 struct dentry **root_dentry) 978{ 979 struct the_nilfs *nilfs = s->s_fs_info; 980 struct nilfs_root *root; 981 int ret; 982 983 mutex_lock(&nilfs->ns_snapshot_mount_mutex); 984 985 down_read(&nilfs->ns_segctor_sem); 986 ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno); 987 up_read(&nilfs->ns_segctor_sem); 988 if (ret < 0) { 989 ret = (ret == -ENOENT) ? -EINVAL : ret; 990 goto out; 991 } else if (!ret) { 992 nilfs_err(s, 993 "The specified checkpoint is not a snapshot (checkpoint number=%llu)", 994 (unsigned long long)cno); 995 ret = -EINVAL; 996 goto out; 997 } 998 999 ret = nilfs_attach_checkpoint(s, cno, false, &root); 1000 if (ret) { 1001 nilfs_err(s, 1002 "error %d while loading snapshot (checkpoint number=%llu)", 1003 ret, (unsigned long long)cno); 1004 goto out; 1005 } 1006 ret = nilfs_get_root_dentry(s, root, root_dentry); 1007 nilfs_put_root(root); 1008 out: 1009 mutex_unlock(&nilfs->ns_snapshot_mount_mutex); 1010 return ret; 1011} 1012 1013/** 1014 * nilfs_tree_is_busy() - try to shrink dentries of a checkpoint 1015 * @root_dentry: root dentry of the tree to be shrunk 1016 * 1017 * This function returns true if the tree was in-use. 1018 */ 1019static bool nilfs_tree_is_busy(struct dentry *root_dentry) 1020{ 1021 shrink_dcache_parent(root_dentry); 1022 return d_count(root_dentry) > 1; 1023} 1024 1025int nilfs_checkpoint_is_mounted(struct super_block *sb, __u64 cno) 1026{ 1027 struct the_nilfs *nilfs = sb->s_fs_info; 1028 struct nilfs_root *root; 1029 struct inode *inode; 1030 struct dentry *dentry; 1031 int ret; 1032 1033 if (cno > nilfs->ns_cno) 1034 return false; 1035 1036 if (cno >= nilfs_last_cno(nilfs)) 1037 return true; /* protect recent checkpoints */ 1038 1039 ret = false; 1040 root = nilfs_lookup_root(nilfs, cno); 1041 if (root) { 1042 inode = nilfs_ilookup(sb, root, NILFS_ROOT_INO); 1043 if (inode) { 1044 dentry = d_find_alias(inode); 1045 if (dentry) { 1046 ret = nilfs_tree_is_busy(dentry); 1047 dput(dentry); 1048 } 1049 iput(inode); 1050 } 1051 nilfs_put_root(root); 1052 } 1053 return ret; 1054} 1055 1056/** 1057 * nilfs_fill_super() - initialize a super block instance 1058 * @sb: super_block 1059 * @data: mount options 1060 * @silent: silent mode flag 1061 * 1062 * This function is called exclusively by nilfs->ns_mount_mutex. 1063 * So, the recovery process is protected from other simultaneous mounts. 1064 */ 1065static int 1066nilfs_fill_super(struct super_block *sb, void *data, int silent) 1067{ 1068 struct the_nilfs *nilfs; 1069 struct nilfs_root *fsroot; 1070 __u64 cno; 1071 int err; 1072 1073 nilfs = alloc_nilfs(sb); 1074 if (!nilfs) 1075 return -ENOMEM; 1076 1077 sb->s_fs_info = nilfs; 1078 1079 err = init_nilfs(nilfs, sb, (char *)data); 1080 if (err) 1081 goto failed_nilfs; 1082 1083 sb->s_op = &nilfs_sops; 1084 sb->s_export_op = &nilfs_export_ops; 1085 sb->s_root = NULL; 1086 sb->s_time_gran = 1; 1087 sb->s_max_links = NILFS_LINK_MAX; 1088 1089 sb->s_bdi = bdi_get(sb->s_bdev->bd_disk->bdi); 1090 1091 err = load_nilfs(nilfs, sb); 1092 if (err) 1093 goto failed_nilfs; 1094 1095 cno = nilfs_last_cno(nilfs); 1096 err = nilfs_attach_checkpoint(sb, cno, true, &fsroot); 1097 if (err) { 1098 nilfs_err(sb, 1099 "error %d while loading last checkpoint (checkpoint number=%llu)", 1100 err, (unsigned long long)cno); 1101 goto failed_unload; 1102 } 1103 1104 if (!sb_rdonly(sb)) { 1105 err = nilfs_attach_log_writer(sb, fsroot); 1106 if (err) 1107 goto failed_checkpoint; 1108 } 1109 1110 err = nilfs_get_root_dentry(sb, fsroot, &sb->s_root); 1111 if (err) 1112 goto failed_segctor; 1113 1114 nilfs_put_root(fsroot); 1115 1116 if (!sb_rdonly(sb)) { 1117 down_write(&nilfs->ns_sem); 1118 nilfs_setup_super(sb, true); 1119 up_write(&nilfs->ns_sem); 1120 } 1121 1122 return 0; 1123 1124 failed_segctor: 1125 nilfs_detach_log_writer(sb); 1126 1127 failed_checkpoint: 1128 nilfs_put_root(fsroot); 1129 1130 failed_unload: 1131 nilfs_sysfs_delete_device_group(nilfs); 1132 iput(nilfs->ns_sufile); 1133 iput(nilfs->ns_cpfile); 1134 iput(nilfs->ns_dat); 1135 1136 failed_nilfs: 1137 destroy_nilfs(nilfs); 1138 return err; 1139} 1140 1141static int nilfs_remount(struct super_block *sb, int *flags, char *data) 1142{ 1143 struct the_nilfs *nilfs = sb->s_fs_info; 1144 unsigned long old_sb_flags; 1145 unsigned long old_mount_opt; 1146 int err; 1147 1148 sync_filesystem(sb); 1149 old_sb_flags = sb->s_flags; 1150 old_mount_opt = nilfs->ns_mount_opt; 1151 1152 if (!parse_options(data, sb, 1)) { 1153 err = -EINVAL; 1154 goto restore_opts; 1155 } 1156 sb->s_flags = (sb->s_flags & ~SB_POSIXACL); 1157 1158 err = -EINVAL; 1159 1160 if (!nilfs_valid_fs(nilfs)) { 1161 nilfs_warn(sb, 1162 "couldn't remount because the filesystem is in an incomplete recovery state"); 1163 goto restore_opts; 1164 } 1165 1166 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb)) 1167 goto out; 1168 if (*flags & SB_RDONLY) { 1169 sb->s_flags |= SB_RDONLY; 1170 1171 /* 1172 * Remounting a valid RW partition RDONLY, so set 1173 * the RDONLY flag and then mark the partition as valid again. 1174 */ 1175 down_write(&nilfs->ns_sem); 1176 nilfs_cleanup_super(sb); 1177 up_write(&nilfs->ns_sem); 1178 } else { 1179 __u64 features; 1180 struct nilfs_root *root; 1181 1182 /* 1183 * Mounting a RDONLY partition read-write, so reread and 1184 * store the current valid flag. (It may have been changed 1185 * by fsck since we originally mounted the partition.) 1186 */ 1187 down_read(&nilfs->ns_sem); 1188 features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) & 1189 ~NILFS_FEATURE_COMPAT_RO_SUPP; 1190 up_read(&nilfs->ns_sem); 1191 if (features) { 1192 nilfs_warn(sb, 1193 "couldn't remount RDWR because of unsupported optional features (%llx)", 1194 (unsigned long long)features); 1195 err = -EROFS; 1196 goto restore_opts; 1197 } 1198 1199 sb->s_flags &= ~SB_RDONLY; 1200 1201 root = NILFS_I(d_inode(sb->s_root))->i_root; 1202 err = nilfs_attach_log_writer(sb, root); 1203 if (err) 1204 goto restore_opts; 1205 1206 down_write(&nilfs->ns_sem); 1207 nilfs_setup_super(sb, true); 1208 up_write(&nilfs->ns_sem); 1209 } 1210 out: 1211 return 0; 1212 1213 restore_opts: 1214 sb->s_flags = old_sb_flags; 1215 nilfs->ns_mount_opt = old_mount_opt; 1216 return err; 1217} 1218 1219struct nilfs_super_data { 1220 __u64 cno; 1221 int flags; 1222}; 1223 1224static int nilfs_parse_snapshot_option(const char *option, 1225 const substring_t *arg, 1226 struct nilfs_super_data *sd) 1227{ 1228 unsigned long long val; 1229 const char *msg = NULL; 1230 int err; 1231 1232 if (!(sd->flags & SB_RDONLY)) { 1233 msg = "read-only option is not specified"; 1234 goto parse_error; 1235 } 1236 1237 err = kstrtoull(arg->from, 0, &val); 1238 if (err) { 1239 if (err == -ERANGE) 1240 msg = "too large checkpoint number"; 1241 else 1242 msg = "malformed argument"; 1243 goto parse_error; 1244 } else if (val == 0) { 1245 msg = "invalid checkpoint number 0"; 1246 goto parse_error; 1247 } 1248 sd->cno = val; 1249 return 0; 1250 1251parse_error: 1252 nilfs_err(NULL, "invalid option \"%s\": %s", option, msg); 1253 return 1; 1254} 1255 1256/** 1257 * nilfs_identify - pre-read mount options needed to identify mount instance 1258 * @data: mount options 1259 * @sd: nilfs_super_data 1260 */ 1261static int nilfs_identify(char *data, struct nilfs_super_data *sd) 1262{ 1263 char *p, *options = data; 1264 substring_t args[MAX_OPT_ARGS]; 1265 int token; 1266 int ret = 0; 1267 1268 do { 1269 p = strsep(&options, ","); 1270 if (p != NULL && *p) { 1271 token = match_token(p, tokens, args); 1272 if (token == Opt_snapshot) 1273 ret = nilfs_parse_snapshot_option(p, &args[0], 1274 sd); 1275 } 1276 if (!options) 1277 break; 1278 BUG_ON(options == data); 1279 *(options - 1) = ','; 1280 } while (!ret); 1281 return ret; 1282} 1283 1284static int nilfs_set_bdev_super(struct super_block *s, void *data) 1285{ 1286 s->s_dev = *(dev_t *)data; 1287 return 0; 1288} 1289 1290static int nilfs_test_bdev_super(struct super_block *s, void *data) 1291{ 1292 return !(s->s_iflags & SB_I_RETIRED) && s->s_dev == *(dev_t *)data; 1293} 1294 1295static struct dentry * 1296nilfs_mount(struct file_system_type *fs_type, int flags, 1297 const char *dev_name, void *data) 1298{ 1299 struct nilfs_super_data sd = { .flags = flags }; 1300 struct super_block *s; 1301 dev_t dev; 1302 int err; 1303 1304 if (nilfs_identify(data, &sd)) 1305 return ERR_PTR(-EINVAL); 1306 1307 err = lookup_bdev(dev_name, &dev); 1308 if (err) 1309 return ERR_PTR(err); 1310 1311 s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, flags, 1312 &dev); 1313 if (IS_ERR(s)) 1314 return ERR_CAST(s); 1315 1316 if (!s->s_root) { 1317 /* 1318 * We drop s_umount here because we need to open the bdev and 1319 * bdev->open_mutex ranks above s_umount (blkdev_put() -> 1320 * __invalidate_device()). It is safe because we have active sb 1321 * reference and SB_BORN is not set yet. 1322 */ 1323 up_write(&s->s_umount); 1324 err = setup_bdev_super(s, flags, NULL); 1325 down_write(&s->s_umount); 1326 if (!err) 1327 err = nilfs_fill_super(s, data, 1328 flags & SB_SILENT ? 1 : 0); 1329 if (err) 1330 goto failed_super; 1331 1332 s->s_flags |= SB_ACTIVE; 1333 } else if (!sd.cno) { 1334 if (nilfs_tree_is_busy(s->s_root)) { 1335 if ((flags ^ s->s_flags) & SB_RDONLY) { 1336 nilfs_err(s, 1337 "the device already has a %s mount.", 1338 sb_rdonly(s) ? "read-only" : "read/write"); 1339 err = -EBUSY; 1340 goto failed_super; 1341 } 1342 } else { 1343 /* 1344 * Try remount to setup mount states if the current 1345 * tree is not mounted and only snapshots use this sb. 1346 */ 1347 err = nilfs_remount(s, &flags, data); 1348 if (err) 1349 goto failed_super; 1350 } 1351 } 1352 1353 if (sd.cno) { 1354 struct dentry *root_dentry; 1355 1356 err = nilfs_attach_snapshot(s, sd.cno, &root_dentry); 1357 if (err) 1358 goto failed_super; 1359 return root_dentry; 1360 } 1361 1362 return dget(s->s_root); 1363 1364 failed_super: 1365 deactivate_locked_super(s); 1366 return ERR_PTR(err); 1367} 1368 1369struct file_system_type nilfs_fs_type = { 1370 .owner = THIS_MODULE, 1371 .name = "nilfs2", 1372 .mount = nilfs_mount, 1373 .kill_sb = kill_block_super, 1374 .fs_flags = FS_REQUIRES_DEV, 1375}; 1376MODULE_ALIAS_FS("nilfs2"); 1377 1378static void nilfs_inode_init_once(void *obj) 1379{ 1380 struct nilfs_inode_info *ii = obj; 1381 1382 INIT_LIST_HEAD(&ii->i_dirty); 1383#ifdef CONFIG_NILFS_XATTR 1384 init_rwsem(&ii->xattr_sem); 1385#endif 1386 inode_init_once(&ii->vfs_inode); 1387} 1388 1389static void nilfs_segbuf_init_once(void *obj) 1390{ 1391 memset(obj, 0, sizeof(struct nilfs_segment_buffer)); 1392} 1393 1394static void nilfs_destroy_cachep(void) 1395{ 1396 /* 1397 * Make sure all delayed rcu free inodes are flushed before we 1398 * destroy cache. 1399 */ 1400 rcu_barrier(); 1401 1402 kmem_cache_destroy(nilfs_inode_cachep); 1403 kmem_cache_destroy(nilfs_transaction_cachep); 1404 kmem_cache_destroy(nilfs_segbuf_cachep); 1405 kmem_cache_destroy(nilfs_btree_path_cache); 1406} 1407 1408static int __init nilfs_init_cachep(void) 1409{ 1410 nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache", 1411 sizeof(struct nilfs_inode_info), 0, 1412 SLAB_RECLAIM_ACCOUNT|SLAB_ACCOUNT, 1413 nilfs_inode_init_once); 1414 if (!nilfs_inode_cachep) 1415 goto fail; 1416 1417 nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache", 1418 sizeof(struct nilfs_transaction_info), 0, 1419 SLAB_RECLAIM_ACCOUNT, NULL); 1420 if (!nilfs_transaction_cachep) 1421 goto fail; 1422 1423 nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache", 1424 sizeof(struct nilfs_segment_buffer), 0, 1425 SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once); 1426 if (!nilfs_segbuf_cachep) 1427 goto fail; 1428 1429 nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache", 1430 sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX, 1431 0, 0, NULL); 1432 if (!nilfs_btree_path_cache) 1433 goto fail; 1434 1435 return 0; 1436 1437fail: 1438 nilfs_destroy_cachep(); 1439 return -ENOMEM; 1440} 1441 1442static int __init init_nilfs_fs(void) 1443{ 1444 int err; 1445 1446 err = nilfs_init_cachep(); 1447 if (err) 1448 goto fail; 1449 1450 err = nilfs_sysfs_init(); 1451 if (err) 1452 goto free_cachep; 1453 1454 err = register_filesystem(&nilfs_fs_type); 1455 if (err) 1456 goto deinit_sysfs_entry; 1457 1458 printk(KERN_INFO "NILFS version 2 loaded\n"); 1459 return 0; 1460 1461deinit_sysfs_entry: 1462 nilfs_sysfs_exit(); 1463free_cachep: 1464 nilfs_destroy_cachep(); 1465fail: 1466 return err; 1467} 1468 1469static void __exit exit_nilfs_fs(void) 1470{ 1471 nilfs_destroy_cachep(); 1472 nilfs_sysfs_exit(); 1473 unregister_filesystem(&nilfs_fs_type); 1474} 1475 1476module_init(init_nilfs_fs) 1477module_exit(exit_nilfs_fs) 1478