1/* SPDX-License-Identifier: GPL-2.0-or-later */ 2/* 3 * linux/include/linux/jbd2.h 4 * 5 * Written by Stephen C. Tweedie <sct@redhat.com> 6 * 7 * Copyright 1998-2000 Red Hat, Inc --- All Rights Reserved 8 * 9 * Definitions for transaction data structures for the buffer cache 10 * filesystem journaling support. 11 */ 12 13#ifndef _LINUX_JBD2_H 14#define _LINUX_JBD2_H 15 16/* Allow this file to be included directly into e2fsprogs */ 17#ifndef __KERNEL__ 18#include "jfs_compat.h" 19#define JBD2_DEBUG 20#else 21 22#include <linux/types.h> 23#include <linux/buffer_head.h> 24#include <linux/journal-head.h> 25#include <linux/stddef.h> 26#include <linux/mutex.h> 27#include <linux/timer.h> 28#include <linux/slab.h> 29#include <linux/bit_spinlock.h> 30#include <linux/blkdev.h> 31#include <crypto/hash.h> 32#endif 33 34#define journal_oom_retry 1 35 36/* 37 * Define JBD2_PARANIOD_IOFAIL to cause a kernel BUG() if ext4 finds 38 * certain classes of error which can occur due to failed IOs. Under 39 * normal use we want ext4 to continue after such errors, because 40 * hardware _can_ fail, but for debugging purposes when running tests on 41 * known-good hardware we may want to trap these errors. 42 */ 43#undef JBD2_PARANOID_IOFAIL 44 45/* 46 * The default maximum commit age, in seconds. 47 */ 48#define JBD2_DEFAULT_MAX_COMMIT_AGE 5 49 50#ifdef CONFIG_JBD2_DEBUG 51/* 52 * Define JBD2_EXPENSIVE_CHECKING to enable more expensive internal 53 * consistency checks. By default we don't do this unless 54 * CONFIG_JBD2_DEBUG is on. 55 */ 56#define JBD2_EXPENSIVE_CHECKING 57void __jbd2_debug(int level, const char *file, const char *func, 58 unsigned int line, const char *fmt, ...); 59 60#define jbd2_debug(n, fmt, a...) \ 61 __jbd2_debug((n), __FILE__, __func__, __LINE__, (fmt), ##a) 62#else 63#define jbd2_debug(n, fmt, a...) no_printk(fmt, ##a) 64#endif 65 66extern void *jbd2_alloc(size_t size, gfp_t flags); 67extern void jbd2_free(void *ptr, size_t size); 68 69#define JBD2_MIN_JOURNAL_BLOCKS 1024 70#define JBD2_DEFAULT_FAST_COMMIT_BLOCKS 256 71 72#ifdef __KERNEL__ 73 74/** 75 * typedef handle_t - The handle_t type represents a single atomic update being performed by some process. 76 * 77 * All filesystem modifications made by the process go 78 * through this handle. Recursive operations (such as quota operations) 79 * are gathered into a single update. 80 * 81 * The buffer credits field is used to account for journaled buffers 82 * being modified by the running process. To ensure that there is 83 * enough log space for all outstanding operations, we need to limit the 84 * number of outstanding buffers possible at any time. When the 85 * operation completes, any buffer credits not used are credited back to 86 * the transaction, so that at all times we know how many buffers the 87 * outstanding updates on a transaction might possibly touch. 88 * 89 * This is an opaque datatype. 90 **/ 91typedef struct jbd2_journal_handle handle_t; /* Atomic operation type */ 92 93 94/** 95 * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem. 96 * 97 * journal_t is linked to from the fs superblock structure. 98 * 99 * We use the journal_t to keep track of all outstanding transaction 100 * activity on the filesystem, and to manage the state of the log 101 * writing process. 102 * 103 * This is an opaque datatype. 104 **/ 105typedef struct journal_s journal_t; /* Journal control structure */ 106#endif 107 108/* 109 * Internal structures used by the logging mechanism: 110 */ 111 112#define JBD2_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */ 113 114/* 115 * On-disk structures 116 */ 117 118/* 119 * Descriptor block types: 120 */ 121 122#define JBD2_DESCRIPTOR_BLOCK 1 123#define JBD2_COMMIT_BLOCK 2 124#define JBD2_SUPERBLOCK_V1 3 125#define JBD2_SUPERBLOCK_V2 4 126#define JBD2_REVOKE_BLOCK 5 127 128/* 129 * Standard header for all descriptor blocks: 130 */ 131typedef struct journal_header_s 132{ 133 __be32 h_magic; 134 __be32 h_blocktype; 135 __be32 h_sequence; 136} journal_header_t; 137 138/* 139 * Checksum types. 140 */ 141#define JBD2_CRC32_CHKSUM 1 142#define JBD2_MD5_CHKSUM 2 143#define JBD2_SHA1_CHKSUM 3 144#define JBD2_CRC32C_CHKSUM 4 145 146#define JBD2_CRC32_CHKSUM_SIZE 4 147 148#define JBD2_CHECKSUM_BYTES (32 / sizeof(u32)) 149/* 150 * Commit block header for storing transactional checksums: 151 * 152 * NOTE: If FEATURE_COMPAT_CHECKSUM (checksum v1) is set, the h_chksum* 153 * fields are used to store a checksum of the descriptor and data blocks. 154 * 155 * If FEATURE_INCOMPAT_CSUM_V2 (checksum v2) is set, then the h_chksum 156 * field is used to store crc32c(uuid+commit_block). Each journal metadata 157 * block gets its own checksum, and data block checksums are stored in 158 * journal_block_tag (in the descriptor). The other h_chksum* fields are 159 * not used. 160 * 161 * If FEATURE_INCOMPAT_CSUM_V3 is set, the descriptor block uses 162 * journal_block_tag3_t to store a full 32-bit checksum. Everything else 163 * is the same as v2. 164 * 165 * Checksum v1, v2, and v3 are mutually exclusive features. 166 */ 167struct commit_header { 168 __be32 h_magic; 169 __be32 h_blocktype; 170 __be32 h_sequence; 171 unsigned char h_chksum_type; 172 unsigned char h_chksum_size; 173 unsigned char h_padding[2]; 174 __be32 h_chksum[JBD2_CHECKSUM_BYTES]; 175 __be64 h_commit_sec; 176 __be32 h_commit_nsec; 177}; 178 179/* 180 * The block tag: used to describe a single buffer in the journal. 181 * t_blocknr_high is only used if INCOMPAT_64BIT is set, so this 182 * raw struct shouldn't be used for pointer math or sizeof() - use 183 * journal_tag_bytes(journal) instead to compute this. 184 */ 185typedef struct journal_block_tag3_s 186{ 187 __be32 t_blocknr; /* The on-disk block number */ 188 __be32 t_flags; /* See below */ 189 __be32 t_blocknr_high; /* most-significant high 32bits. */ 190 __be32 t_checksum; /* crc32c(uuid+seq+block) */ 191} journal_block_tag3_t; 192 193typedef struct journal_block_tag_s 194{ 195 __be32 t_blocknr; /* The on-disk block number */ 196 __be16 t_checksum; /* truncated crc32c(uuid+seq+block) */ 197 __be16 t_flags; /* See below */ 198 __be32 t_blocknr_high; /* most-significant high 32bits. */ 199} journal_block_tag_t; 200 201/* Tail of descriptor or revoke block, for checksumming */ 202struct jbd2_journal_block_tail { 203 __be32 t_checksum; /* crc32c(uuid+descr_block) */ 204}; 205 206/* 207 * The revoke descriptor: used on disk to describe a series of blocks to 208 * be revoked from the log 209 */ 210typedef struct jbd2_journal_revoke_header_s 211{ 212 journal_header_t r_header; 213 __be32 r_count; /* Count of bytes used in the block */ 214} jbd2_journal_revoke_header_t; 215 216/* Definitions for the journal tag flags word: */ 217#define JBD2_FLAG_ESCAPE 1 /* on-disk block is escaped */ 218#define JBD2_FLAG_SAME_UUID 2 /* block has same uuid as previous */ 219#define JBD2_FLAG_DELETED 4 /* block deleted by this transaction */ 220#define JBD2_FLAG_LAST_TAG 8 /* last tag in this descriptor block */ 221 222 223/* 224 * The journal superblock. All fields are in big-endian byte order. 225 */ 226typedef struct journal_superblock_s 227{ 228/* 0x0000 */ 229 journal_header_t s_header; 230 231/* 0x000C */ 232 /* Static information describing the journal */ 233 __be32 s_blocksize; /* journal device blocksize */ 234 __be32 s_maxlen; /* total blocks in journal file */ 235 __be32 s_first; /* first block of log information */ 236 237/* 0x0018 */ 238 /* Dynamic information describing the current state of the log */ 239 __be32 s_sequence; /* first commit ID expected in log */ 240 __be32 s_start; /* blocknr of start of log */ 241 242/* 0x0020 */ 243 /* Error value, as set by jbd2_journal_abort(). */ 244 __be32 s_errno; 245 246/* 0x0024 */ 247 /* Remaining fields are only valid in a version-2 superblock */ 248 __be32 s_feature_compat; /* compatible feature set */ 249 __be32 s_feature_incompat; /* incompatible feature set */ 250 __be32 s_feature_ro_compat; /* readonly-compatible feature set */ 251/* 0x0030 */ 252 __u8 s_uuid[16]; /* 128-bit uuid for journal */ 253 254/* 0x0040 */ 255 __be32 s_nr_users; /* Nr of filesystems sharing log */ 256 257 __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/ 258 259/* 0x0048 */ 260 __be32 s_max_transaction; /* Limit of journal blocks per trans.*/ 261 __be32 s_max_trans_data; /* Limit of data blocks per trans. */ 262 263/* 0x0050 */ 264 __u8 s_checksum_type; /* checksum type */ 265 __u8 s_padding2[3]; 266/* 0x0054 */ 267 __be32 s_num_fc_blks; /* Number of fast commit blocks */ 268 __be32 s_head; /* blocknr of head of log, only uptodate 269 * while the filesystem is clean */ 270/* 0x005C */ 271 __u32 s_padding[40]; 272 __be32 s_checksum; /* crc32c(superblock) */ 273 274/* 0x0100 */ 275 __u8 s_users[16*48]; /* ids of all fs'es sharing the log */ 276/* 0x0400 */ 277} journal_superblock_t; 278 279#define JBD2_FEATURE_COMPAT_CHECKSUM 0x00000001 280 281#define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001 282#define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002 283#define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT 0x00000004 284#define JBD2_FEATURE_INCOMPAT_CSUM_V2 0x00000008 285#define JBD2_FEATURE_INCOMPAT_CSUM_V3 0x00000010 286#define JBD2_FEATURE_INCOMPAT_FAST_COMMIT 0x00000020 287 288/* See "journal feature predicate functions" below */ 289 290/* Features known to this kernel version: */ 291#define JBD2_KNOWN_COMPAT_FEATURES JBD2_FEATURE_COMPAT_CHECKSUM 292#define JBD2_KNOWN_ROCOMPAT_FEATURES 0 293#define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \ 294 JBD2_FEATURE_INCOMPAT_64BIT | \ 295 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | \ 296 JBD2_FEATURE_INCOMPAT_CSUM_V2 | \ 297 JBD2_FEATURE_INCOMPAT_CSUM_V3 | \ 298 JBD2_FEATURE_INCOMPAT_FAST_COMMIT) 299 300#ifdef __KERNEL__ 301 302#include <linux/fs.h> 303#include <linux/sched.h> 304 305enum jbd_state_bits { 306 BH_JBD /* Has an attached ext3 journal_head */ 307 = BH_PrivateStart, 308 BH_JWrite, /* Being written to log (@@@ DEBUGGING) */ 309 BH_Freed, /* Has been freed (truncated) */ 310 BH_Revoked, /* Has been revoked from the log */ 311 BH_RevokeValid, /* Revoked flag is valid */ 312 BH_JBDDirty, /* Is dirty but journaled */ 313 BH_JournalHead, /* Pins bh->b_private and jh->b_bh */ 314 BH_Shadow, /* IO on shadow buffer is running */ 315 BH_Verified, /* Metadata block has been verified ok */ 316 BH_JBDPrivateStart, /* First bit available for private use by FS */ 317}; 318 319BUFFER_FNS(JBD, jbd) 320BUFFER_FNS(JWrite, jwrite) 321BUFFER_FNS(JBDDirty, jbddirty) 322TAS_BUFFER_FNS(JBDDirty, jbddirty) 323BUFFER_FNS(Revoked, revoked) 324TAS_BUFFER_FNS(Revoked, revoked) 325BUFFER_FNS(RevokeValid, revokevalid) 326TAS_BUFFER_FNS(RevokeValid, revokevalid) 327BUFFER_FNS(Freed, freed) 328BUFFER_FNS(Shadow, shadow) 329BUFFER_FNS(Verified, verified) 330 331static inline struct buffer_head *jh2bh(struct journal_head *jh) 332{ 333 return jh->b_bh; 334} 335 336static inline struct journal_head *bh2jh(struct buffer_head *bh) 337{ 338 return bh->b_private; 339} 340 341static inline void jbd_lock_bh_journal_head(struct buffer_head *bh) 342{ 343 bit_spin_lock(BH_JournalHead, &bh->b_state); 344} 345 346static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh) 347{ 348 bit_spin_unlock(BH_JournalHead, &bh->b_state); 349} 350 351#define J_ASSERT(assert) BUG_ON(!(assert)) 352 353#define J_ASSERT_BH(bh, expr) J_ASSERT(expr) 354#define J_ASSERT_JH(jh, expr) J_ASSERT(expr) 355 356#if defined(JBD2_PARANOID_IOFAIL) 357#define J_EXPECT(expr, why...) J_ASSERT(expr) 358#define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr) 359#define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr) 360#else 361#define __journal_expect(expr, why...) \ 362 ({ \ 363 int val = (expr); \ 364 if (!val) { \ 365 printk(KERN_ERR \ 366 "JBD2 unexpected failure: %s: %s;\n", \ 367 __func__, #expr); \ 368 printk(KERN_ERR why "\n"); \ 369 } \ 370 val; \ 371 }) 372#define J_EXPECT(expr, why...) __journal_expect(expr, ## why) 373#define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why) 374#define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why) 375#endif 376 377/* Flags in jbd_inode->i_flags */ 378#define __JI_COMMIT_RUNNING 0 379#define __JI_WRITE_DATA 1 380#define __JI_WAIT_DATA 2 381 382/* 383 * Commit of the inode data in progress. We use this flag to protect us from 384 * concurrent deletion of inode. We cannot use reference to inode for this 385 * since we cannot afford doing last iput() on behalf of kjournald 386 */ 387#define JI_COMMIT_RUNNING (1 << __JI_COMMIT_RUNNING) 388/* Write allocated dirty buffers in this inode before commit */ 389#define JI_WRITE_DATA (1 << __JI_WRITE_DATA) 390/* Wait for outstanding data writes for this inode before commit */ 391#define JI_WAIT_DATA (1 << __JI_WAIT_DATA) 392 393/** 394 * struct jbd2_inode - The jbd_inode type is the structure linking inodes in 395 * ordered mode present in a transaction so that we can sync them during commit. 396 */ 397struct jbd2_inode { 398 /** 399 * @i_transaction: 400 * 401 * Which transaction does this inode belong to? Either the running 402 * transaction or the committing one. [j_list_lock] 403 */ 404 transaction_t *i_transaction; 405 406 /** 407 * @i_next_transaction: 408 * 409 * Pointer to the running transaction modifying inode's data in case 410 * there is already a committing transaction touching it. [j_list_lock] 411 */ 412 transaction_t *i_next_transaction; 413 414 /** 415 * @i_list: List of inodes in the i_transaction [j_list_lock] 416 */ 417 struct list_head i_list; 418 419 /** 420 * @i_vfs_inode: 421 * 422 * VFS inode this inode belongs to [constant for lifetime of structure] 423 */ 424 struct inode *i_vfs_inode; 425 426 /** 427 * @i_flags: Flags of inode [j_list_lock] 428 */ 429 unsigned long i_flags; 430 431 /** 432 * @i_dirty_start: 433 * 434 * Offset in bytes where the dirty range for this inode starts. 435 * [j_list_lock] 436 */ 437 loff_t i_dirty_start; 438 439 /** 440 * @i_dirty_end: 441 * 442 * Inclusive offset in bytes where the dirty range for this inode 443 * ends. [j_list_lock] 444 */ 445 loff_t i_dirty_end; 446}; 447 448struct jbd2_revoke_table_s; 449 450/** 451 * struct jbd2_journal_handle - The jbd2_journal_handle type is the concrete 452 * type associated with handle_t. 453 * @h_transaction: Which compound transaction is this update a part of? 454 * @h_journal: Which journal handle belongs to - used iff h_reserved set. 455 * @h_rsv_handle: Handle reserved for finishing the logical operation. 456 * @h_total_credits: Number of remaining buffers we are allowed to add to 457 * journal. These are dirty buffers and revoke descriptor blocks. 458 * @h_revoke_credits: Number of remaining revoke records available for handle 459 * @h_ref: Reference count on this handle. 460 * @h_err: Field for caller's use to track errors through large fs operations. 461 * @h_sync: Flag for sync-on-close. 462 * @h_jdata: Flag to force data journaling. 463 * @h_reserved: Flag for handle for reserved credits. 464 * @h_aborted: Flag indicating fatal error on handle. 465 * @h_type: For handle statistics. 466 * @h_line_no: For handle statistics. 467 * @h_start_jiffies: Handle Start time. 468 * @h_requested_credits: Holds @h_total_credits after handle is started. 469 * @h_revoke_credits_requested: Holds @h_revoke_credits after handle is started. 470 * @saved_alloc_context: Saved context while transaction is open. 471 **/ 472 473/* Docbook can't yet cope with the bit fields, but will leave the documentation 474 * in so it can be fixed later. 475 */ 476 477struct jbd2_journal_handle 478{ 479 union { 480 transaction_t *h_transaction; 481 /* Which journal handle belongs to - used iff h_reserved set */ 482 journal_t *h_journal; 483 }; 484 485 handle_t *h_rsv_handle; 486 int h_total_credits; 487 int h_revoke_credits; 488 int h_revoke_credits_requested; 489 int h_ref; 490 int h_err; 491 492 /* Flags [no locking] */ 493 unsigned int h_sync: 1; 494 unsigned int h_jdata: 1; 495 unsigned int h_reserved: 1; 496 unsigned int h_aborted: 1; 497 unsigned int h_type: 8; 498 unsigned int h_line_no: 16; 499 500 unsigned long h_start_jiffies; 501 unsigned int h_requested_credits; 502 503 unsigned int saved_alloc_context; 504}; 505 506 507/* 508 * Some stats for checkpoint phase 509 */ 510struct transaction_chp_stats_s { 511 unsigned long cs_chp_time; 512 __u32 cs_forced_to_close; 513 __u32 cs_written; 514 __u32 cs_dropped; 515}; 516 517/* The transaction_t type is the guts of the journaling mechanism. It 518 * tracks a compound transaction through its various states: 519 * 520 * RUNNING: accepting new updates 521 * LOCKED: Updates still running but we don't accept new ones 522 * RUNDOWN: Updates are tidying up but have finished requesting 523 * new buffers to modify (state not used for now) 524 * FLUSH: All updates complete, but we are still writing to disk 525 * COMMIT: All data on disk, writing commit record 526 * FINISHED: We still have to keep the transaction for checkpointing. 527 * 528 * The transaction keeps track of all of the buffers modified by a 529 * running transaction, and all of the buffers committed but not yet 530 * flushed to home for finished transactions. 531 * (Locking Documentation improved by LockDoc) 532 */ 533 534/* 535 * Lock ranking: 536 * 537 * j_list_lock 538 * ->jbd_lock_bh_journal_head() (This is "innermost") 539 * 540 * j_state_lock 541 * ->b_state_lock 542 * 543 * b_state_lock 544 * ->j_list_lock 545 * 546 * j_state_lock 547 * ->j_list_lock (journal_unmap_buffer) 548 * 549 */ 550 551struct transaction_s 552{ 553 /* Pointer to the journal for this transaction. [no locking] */ 554 journal_t *t_journal; 555 556 /* Sequence number for this transaction [no locking] */ 557 tid_t t_tid; 558 559 /* 560 * Transaction's current state 561 * [no locking - only kjournald2 alters this] 562 * [j_list_lock] guards transition of a transaction into T_FINISHED 563 * state and subsequent call of __jbd2_journal_drop_transaction() 564 * FIXME: needs barriers 565 * KLUDGE: [use j_state_lock] 566 */ 567 enum { 568 T_RUNNING, 569 T_LOCKED, 570 T_SWITCH, 571 T_FLUSH, 572 T_COMMIT, 573 T_COMMIT_DFLUSH, 574 T_COMMIT_JFLUSH, 575 T_COMMIT_CALLBACK, 576 T_FINISHED 577 } t_state; 578 579 /* 580 * Where in the log does this transaction's commit start? [no locking] 581 */ 582 unsigned long t_log_start; 583 584 /* 585 * Number of buffers on the t_buffers list [j_list_lock, no locks 586 * needed for jbd2 thread] 587 */ 588 int t_nr_buffers; 589 590 /* 591 * Doubly-linked circular list of all buffers reserved but not yet 592 * modified by this transaction [j_list_lock, no locks needed fo 593 * jbd2 thread] 594 */ 595 struct journal_head *t_reserved_list; 596 597 /* 598 * Doubly-linked circular list of all metadata buffers owned by this 599 * transaction [j_list_lock, no locks needed for jbd2 thread] 600 */ 601 struct journal_head *t_buffers; 602 603 /* 604 * Doubly-linked circular list of all forget buffers (superseded 605 * buffers which we can un-checkpoint once this transaction commits) 606 * [j_list_lock] 607 */ 608 struct journal_head *t_forget; 609 610 /* 611 * Doubly-linked circular list of all buffers still to be flushed before 612 * this transaction can be checkpointed. [j_list_lock] 613 */ 614 struct journal_head *t_checkpoint_list; 615 616 /* 617 * Doubly-linked circular list of metadata buffers being 618 * shadowed by log IO. The IO buffers on the iobuf list and 619 * the shadow buffers on this list match each other one for 620 * one at all times. [j_list_lock, no locks needed for jbd2 621 * thread] 622 */ 623 struct journal_head *t_shadow_list; 624 625 /* 626 * List of inodes associated with the transaction; e.g., ext4 uses 627 * this to track inodes in data=ordered and data=journal mode that 628 * need special handling on transaction commit; also used by ocfs2. 629 * [j_list_lock] 630 */ 631 struct list_head t_inode_list; 632 633 /* 634 * Longest time some handle had to wait for running transaction 635 */ 636 unsigned long t_max_wait; 637 638 /* 639 * When transaction started 640 */ 641 unsigned long t_start; 642 643 /* 644 * When commit was requested [j_state_lock] 645 */ 646 unsigned long t_requested; 647 648 /* 649 * Checkpointing stats [j_list_lock] 650 */ 651 struct transaction_chp_stats_s t_chp_stats; 652 653 /* 654 * Number of outstanding updates running on this transaction 655 * [none] 656 */ 657 atomic_t t_updates; 658 659 /* 660 * Number of blocks reserved for this transaction in the journal. 661 * This is including all credits reserved when starting transaction 662 * handles as well as all journal descriptor blocks needed for this 663 * transaction. [none] 664 */ 665 atomic_t t_outstanding_credits; 666 667 /* 668 * Number of revoke records for this transaction added by already 669 * stopped handles. [none] 670 */ 671 atomic_t t_outstanding_revokes; 672 673 /* 674 * How many handles used this transaction? [none] 675 */ 676 atomic_t t_handle_count; 677 678 /* 679 * Forward and backward links for the circular list of all transactions 680 * awaiting checkpoint. [j_list_lock] 681 */ 682 transaction_t *t_cpnext, *t_cpprev; 683 684 /* 685 * When will the transaction expire (become due for commit), in jiffies? 686 * [no locking] 687 */ 688 unsigned long t_expires; 689 690 /* 691 * When this transaction started, in nanoseconds [no locking] 692 */ 693 ktime_t t_start_time; 694 695 /* 696 * This transaction is being forced and some process is 697 * waiting for it to finish. 698 */ 699 unsigned int t_synchronous_commit:1; 700 701 /* Disk flush needs to be sent to fs partition [no locking] */ 702 int t_need_data_flush; 703 704 /* 705 * For use by the filesystem to store fs-specific data 706 * structures associated with the transaction 707 */ 708 struct list_head t_private_list; 709}; 710 711struct transaction_run_stats_s { 712 unsigned long rs_wait; 713 unsigned long rs_request_delay; 714 unsigned long rs_running; 715 unsigned long rs_locked; 716 unsigned long rs_flushing; 717 unsigned long rs_logging; 718 719 __u32 rs_handle_count; 720 __u32 rs_blocks; 721 __u32 rs_blocks_logged; 722}; 723 724struct transaction_stats_s { 725 unsigned long ts_tid; 726 unsigned long ts_requested; 727 struct transaction_run_stats_s run; 728}; 729 730static inline unsigned long 731jbd2_time_diff(unsigned long start, unsigned long end) 732{ 733 if (end >= start) 734 return end - start; 735 736 return end + (MAX_JIFFY_OFFSET - start); 737} 738 739#define JBD2_NR_BATCH 64 740 741enum passtype {PASS_SCAN, PASS_REVOKE, PASS_REPLAY}; 742 743#define JBD2_FC_REPLAY_STOP 0 744#define JBD2_FC_REPLAY_CONTINUE 1 745 746/** 747 * struct journal_s - The journal_s type is the concrete type associated with 748 * journal_t. 749 */ 750struct journal_s 751{ 752 /** 753 * @j_flags: General journaling state flags [j_state_lock, 754 * no lock for quick racy checks] 755 */ 756 unsigned long j_flags; 757 758 /** 759 * @j_errno: 760 * 761 * Is there an outstanding uncleared error on the journal (from a prior 762 * abort)? [j_state_lock] 763 */ 764 int j_errno; 765 766 /** 767 * @j_abort_mutex: Lock the whole aborting procedure. 768 */ 769 struct mutex j_abort_mutex; 770 771 /** 772 * @j_sb_buffer: The first part of the superblock buffer. 773 */ 774 struct buffer_head *j_sb_buffer; 775 776 /** 777 * @j_superblock: The second part of the superblock buffer. 778 */ 779 journal_superblock_t *j_superblock; 780 781 /** 782 * @j_state_lock: Protect the various scalars in the journal. 783 */ 784 rwlock_t j_state_lock; 785 786 /** 787 * @j_barrier_count: 788 * 789 * Number of processes waiting to create a barrier lock [j_state_lock, 790 * no lock for quick racy checks] 791 */ 792 int j_barrier_count; 793 794 /** 795 * @j_barrier: The barrier lock itself. 796 */ 797 struct mutex j_barrier; 798 799 /** 800 * @j_running_transaction: 801 * 802 * Transactions: The current running transaction... 803 * [j_state_lock, no lock for quick racy checks] [caller holding 804 * open handle] 805 */ 806 transaction_t *j_running_transaction; 807 808 /** 809 * @j_committing_transaction: 810 * 811 * the transaction we are pushing to disk 812 * [j_state_lock] [caller holding open handle] 813 */ 814 transaction_t *j_committing_transaction; 815 816 /** 817 * @j_checkpoint_transactions: 818 * 819 * ... and a linked circular list of all transactions waiting for 820 * checkpointing. [j_list_lock] 821 */ 822 transaction_t *j_checkpoint_transactions; 823 824 /** 825 * @j_wait_transaction_locked: 826 * 827 * Wait queue for waiting for a locked transaction to start committing, 828 * or for a barrier lock to be released. 829 */ 830 wait_queue_head_t j_wait_transaction_locked; 831 832 /** 833 * @j_wait_done_commit: Wait queue for waiting for commit to complete. 834 */ 835 wait_queue_head_t j_wait_done_commit; 836 837 /** 838 * @j_wait_commit: Wait queue to trigger commit. 839 */ 840 wait_queue_head_t j_wait_commit; 841 842 /** 843 * @j_wait_updates: Wait queue to wait for updates to complete. 844 */ 845 wait_queue_head_t j_wait_updates; 846 847 /** 848 * @j_wait_reserved: 849 * 850 * Wait queue to wait for reserved buffer credits to drop. 851 */ 852 wait_queue_head_t j_wait_reserved; 853 854 /** 855 * @j_fc_wait: 856 * 857 * Wait queue to wait for completion of async fast commits. 858 */ 859 wait_queue_head_t j_fc_wait; 860 861 /** 862 * @j_checkpoint_mutex: 863 * 864 * Semaphore for locking against concurrent checkpoints. 865 */ 866 struct mutex j_checkpoint_mutex; 867 868 /** 869 * @j_chkpt_bhs: 870 * 871 * List of buffer heads used by the checkpoint routine. This 872 * was moved from jbd2_log_do_checkpoint() to reduce stack 873 * usage. Access to this array is controlled by the 874 * @j_checkpoint_mutex. [j_checkpoint_mutex] 875 */ 876 struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH]; 877 878 /** 879 * @j_shrinker: 880 * 881 * Journal head shrinker, reclaim buffer's journal head which 882 * has been written back. 883 */ 884 struct shrinker *j_shrinker; 885 886 /** 887 * @j_checkpoint_jh_count: 888 * 889 * Number of journal buffers on the checkpoint list. [j_list_lock] 890 */ 891 struct percpu_counter j_checkpoint_jh_count; 892 893 /** 894 * @j_shrink_transaction: 895 * 896 * Record next transaction will shrink on the checkpoint list. 897 * [j_list_lock] 898 */ 899 transaction_t *j_shrink_transaction; 900 901 /** 902 * @j_head: 903 * 904 * Journal head: identifies the first unused block in the journal. 905 * [j_state_lock] 906 */ 907 unsigned long j_head; 908 909 /** 910 * @j_tail: 911 * 912 * Journal tail: identifies the oldest still-used block in the journal. 913 * [j_state_lock] 914 */ 915 unsigned long j_tail; 916 917 /** 918 * @j_free: 919 * 920 * Journal free: how many free blocks are there in the journal? 921 * [j_state_lock] 922 */ 923 unsigned long j_free; 924 925 /** 926 * @j_first: 927 * 928 * The block number of the first usable block in the journal 929 * [j_state_lock]. 930 */ 931 unsigned long j_first; 932 933 /** 934 * @j_last: 935 * 936 * The block number one beyond the last usable block in the journal 937 * [j_state_lock]. 938 */ 939 unsigned long j_last; 940 941 /** 942 * @j_fc_first: 943 * 944 * The block number of the first fast commit block in the journal 945 * [j_state_lock]. 946 */ 947 unsigned long j_fc_first; 948 949 /** 950 * @j_fc_off: 951 * 952 * Number of fast commit blocks currently allocated. Accessed only 953 * during fast commit. Currently only process can do fast commit, so 954 * this field is not protected by any lock. 955 */ 956 unsigned long j_fc_off; 957 958 /** 959 * @j_fc_last: 960 * 961 * The block number one beyond the last fast commit block in the journal 962 * [j_state_lock]. 963 */ 964 unsigned long j_fc_last; 965 966 /** 967 * @j_dev: Device where we store the journal. 968 */ 969 struct block_device *j_dev; 970 971 /** 972 * @j_blocksize: Block size for the location where we store the journal. 973 */ 974 int j_blocksize; 975 976 /** 977 * @j_blk_offset: 978 * 979 * Starting block offset into the device where we store the journal. 980 */ 981 unsigned long long j_blk_offset; 982 983 /** 984 * @j_devname: Journal device name. 985 */ 986 char j_devname[BDEVNAME_SIZE+24]; 987 988 /** 989 * @j_fs_dev: 990 * 991 * Device which holds the client fs. For internal journal this will be 992 * equal to j_dev. 993 */ 994 struct block_device *j_fs_dev; 995 996 /** 997 * @j_fs_dev_wb_err: 998 * 999 * Records the errseq of the client fs's backing block device. 1000 */ 1001 errseq_t j_fs_dev_wb_err; 1002 1003 /** 1004 * @j_total_len: Total maximum capacity of the journal region on disk. 1005 */ 1006 unsigned int j_total_len; 1007 1008 /** 1009 * @j_reserved_credits: 1010 * 1011 * Number of buffers reserved from the running transaction. 1012 */ 1013 atomic_t j_reserved_credits; 1014 1015 /** 1016 * @j_list_lock: Protects the buffer lists and internal buffer state. 1017 */ 1018 spinlock_t j_list_lock; 1019 1020 /** 1021 * @j_inode: 1022 * 1023 * Optional inode where we store the journal. If present, all 1024 * journal block numbers are mapped into this inode via bmap(). 1025 */ 1026 struct inode *j_inode; 1027 1028 /** 1029 * @j_tail_sequence: 1030 * 1031 * Sequence number of the oldest transaction in the log [j_state_lock] 1032 */ 1033 tid_t j_tail_sequence; 1034 1035 /** 1036 * @j_transaction_sequence: 1037 * 1038 * Sequence number of the next transaction to grant [j_state_lock] 1039 */ 1040 tid_t j_transaction_sequence; 1041 1042 /** 1043 * @j_commit_sequence: 1044 * 1045 * Sequence number of the most recently committed transaction 1046 * [j_state_lock, no lock for quick racy checks] 1047 */ 1048 tid_t j_commit_sequence; 1049 1050 /** 1051 * @j_commit_request: 1052 * 1053 * Sequence number of the most recent transaction wanting commit 1054 * [j_state_lock, no lock for quick racy checks] 1055 */ 1056 tid_t j_commit_request; 1057 1058 /** 1059 * @j_uuid: 1060 * 1061 * Journal uuid: identifies the object (filesystem, LVM volume etc) 1062 * backed by this journal. This will eventually be replaced by an array 1063 * of uuids, allowing us to index multiple devices within a single 1064 * journal and to perform atomic updates across them. 1065 */ 1066 __u8 j_uuid[16]; 1067 1068 /** 1069 * @j_task: Pointer to the current commit thread for this journal. 1070 */ 1071 struct task_struct *j_task; 1072 1073 /** 1074 * @j_max_transaction_buffers: 1075 * 1076 * Maximum number of metadata buffers to allow in a single compound 1077 * commit transaction. 1078 */ 1079 int j_max_transaction_buffers; 1080 1081 /** 1082 * @j_revoke_records_per_block: 1083 * 1084 * Number of revoke records that fit in one descriptor block. 1085 */ 1086 int j_revoke_records_per_block; 1087 1088 /** 1089 * @j_commit_interval: 1090 * 1091 * What is the maximum transaction lifetime before we begin a commit? 1092 */ 1093 unsigned long j_commit_interval; 1094 1095 /** 1096 * @j_commit_timer: The timer used to wakeup the commit thread. 1097 */ 1098 struct timer_list j_commit_timer; 1099 1100 /** 1101 * @j_revoke_lock: Protect the revoke table. 1102 */ 1103 spinlock_t j_revoke_lock; 1104 1105 /** 1106 * @j_revoke: 1107 * 1108 * The revoke table - maintains the list of revoked blocks in the 1109 * current transaction. 1110 */ 1111 struct jbd2_revoke_table_s *j_revoke; 1112 1113 /** 1114 * @j_revoke_table: Alternate revoke tables for j_revoke. 1115 */ 1116 struct jbd2_revoke_table_s *j_revoke_table[2]; 1117 1118 /** 1119 * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction. 1120 */ 1121 struct buffer_head **j_wbuf; 1122 1123 /** 1124 * @j_fc_wbuf: Array of fast commit bhs for fast commit. Accessed only 1125 * during a fast commit. Currently only process can do fast commit, so 1126 * this field is not protected by any lock. 1127 */ 1128 struct buffer_head **j_fc_wbuf; 1129 1130 /** 1131 * @j_wbufsize: 1132 * 1133 * Size of @j_wbuf array. 1134 */ 1135 int j_wbufsize; 1136 1137 /** 1138 * @j_fc_wbufsize: 1139 * 1140 * Size of @j_fc_wbuf array. 1141 */ 1142 int j_fc_wbufsize; 1143 1144 /** 1145 * @j_last_sync_writer: 1146 * 1147 * The pid of the last person to run a synchronous operation 1148 * through the journal. 1149 */ 1150 pid_t j_last_sync_writer; 1151 1152 /** 1153 * @j_average_commit_time: 1154 * 1155 * The average amount of time in nanoseconds it takes to commit a 1156 * transaction to disk. [j_state_lock] 1157 */ 1158 u64 j_average_commit_time; 1159 1160 /** 1161 * @j_min_batch_time: 1162 * 1163 * Minimum time that we should wait for additional filesystem operations 1164 * to get batched into a synchronous handle in microseconds. 1165 */ 1166 u32 j_min_batch_time; 1167 1168 /** 1169 * @j_max_batch_time: 1170 * 1171 * Maximum time that we should wait for additional filesystem operations 1172 * to get batched into a synchronous handle in microseconds. 1173 */ 1174 u32 j_max_batch_time; 1175 1176 /** 1177 * @j_commit_callback: 1178 * 1179 * This function is called when a transaction is closed. 1180 */ 1181 void (*j_commit_callback)(journal_t *, 1182 transaction_t *); 1183 1184 /** 1185 * @j_submit_inode_data_buffers: 1186 * 1187 * This function is called for all inodes associated with the 1188 * committing transaction marked with JI_WRITE_DATA flag 1189 * before we start to write out the transaction to the journal. 1190 */ 1191 int (*j_submit_inode_data_buffers) 1192 (struct jbd2_inode *); 1193 1194 /** 1195 * @j_finish_inode_data_buffers: 1196 * 1197 * This function is called for all inodes associated with the 1198 * committing transaction marked with JI_WAIT_DATA flag 1199 * after we have written the transaction to the journal 1200 * but before we write out the commit block. 1201 */ 1202 int (*j_finish_inode_data_buffers) 1203 (struct jbd2_inode *); 1204 1205 /* 1206 * Journal statistics 1207 */ 1208 1209 /** 1210 * @j_history_lock: Protect the transactions statistics history. 1211 */ 1212 spinlock_t j_history_lock; 1213 1214 /** 1215 * @j_proc_entry: procfs entry for the jbd statistics directory. 1216 */ 1217 struct proc_dir_entry *j_proc_entry; 1218 1219 /** 1220 * @j_stats: Overall statistics. 1221 */ 1222 struct transaction_stats_s j_stats; 1223 1224 /** 1225 * @j_failed_commit: Failed journal commit ID. 1226 */ 1227 unsigned int j_failed_commit; 1228 1229 /** 1230 * @j_private: 1231 * 1232 * An opaque pointer to fs-private information. ext3 puts its 1233 * superblock pointer here. 1234 */ 1235 void *j_private; 1236 1237 /** 1238 * @j_chksum_driver: 1239 * 1240 * Reference to checksum algorithm driver via cryptoapi. 1241 */ 1242 struct crypto_shash *j_chksum_driver; 1243 1244 /** 1245 * @j_csum_seed: 1246 * 1247 * Precomputed journal UUID checksum for seeding other checksums. 1248 */ 1249 __u32 j_csum_seed; 1250 1251#ifdef CONFIG_DEBUG_LOCK_ALLOC 1252 /** 1253 * @j_trans_commit_map: 1254 * 1255 * Lockdep entity to track transaction commit dependencies. Handles 1256 * hold this "lock" for read, when we wait for commit, we acquire the 1257 * "lock" for writing. This matches the properties of jbd2 journalling 1258 * where the running transaction has to wait for all handles to be 1259 * dropped to commit that transaction and also acquiring a handle may 1260 * require transaction commit to finish. 1261 */ 1262 struct lockdep_map j_trans_commit_map; 1263#endif 1264 1265 /** 1266 * @j_fc_cleanup_callback: 1267 * 1268 * Clean-up after fast commit or full commit. JBD2 calls this function 1269 * after every commit operation. 1270 */ 1271 void (*j_fc_cleanup_callback)(struct journal_s *journal, int full, tid_t tid); 1272 1273 /** 1274 * @j_fc_replay_callback: 1275 * 1276 * File-system specific function that performs replay of a fast 1277 * commit. JBD2 calls this function for each fast commit block found in 1278 * the journal. This function should return JBD2_FC_REPLAY_CONTINUE 1279 * to indicate that the block was processed correctly and more fast 1280 * commit replay should continue. Return value of JBD2_FC_REPLAY_STOP 1281 * indicates the end of replay (no more blocks remaining). A negative 1282 * return value indicates error. 1283 */ 1284 int (*j_fc_replay_callback)(struct journal_s *journal, 1285 struct buffer_head *bh, 1286 enum passtype pass, int off, 1287 tid_t expected_commit_id); 1288 1289 /** 1290 * @j_bmap: 1291 * 1292 * Bmap function that should be used instead of the generic 1293 * VFS bmap function. 1294 */ 1295 int (*j_bmap)(struct journal_s *journal, sector_t *block); 1296}; 1297 1298#define jbd2_might_wait_for_commit(j) \ 1299 do { \ 1300 rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \ 1301 rwsem_release(&j->j_trans_commit_map, _THIS_IP_); \ 1302 } while (0) 1303 1304/* 1305 * We can support any known requested features iff the 1306 * superblock is not in version 1. Otherwise we fail to support any 1307 * extended sb features. 1308 */ 1309static inline bool jbd2_format_support_feature(journal_t *j) 1310{ 1311 return j->j_superblock->s_header.h_blocktype != 1312 cpu_to_be32(JBD2_SUPERBLOCK_V1); 1313} 1314 1315/* journal feature predicate functions */ 1316#define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \ 1317static inline bool jbd2_has_feature_##name(journal_t *j) \ 1318{ \ 1319 return (jbd2_format_support_feature(j) && \ 1320 ((j)->j_superblock->s_feature_compat & \ 1321 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \ 1322} \ 1323static inline void jbd2_set_feature_##name(journal_t *j) \ 1324{ \ 1325 (j)->j_superblock->s_feature_compat |= \ 1326 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1327} \ 1328static inline void jbd2_clear_feature_##name(journal_t *j) \ 1329{ \ 1330 (j)->j_superblock->s_feature_compat &= \ 1331 ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1332} 1333 1334#define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \ 1335static inline bool jbd2_has_feature_##name(journal_t *j) \ 1336{ \ 1337 return (jbd2_format_support_feature(j) && \ 1338 ((j)->j_superblock->s_feature_ro_compat & \ 1339 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \ 1340} \ 1341static inline void jbd2_set_feature_##name(journal_t *j) \ 1342{ \ 1343 (j)->j_superblock->s_feature_ro_compat |= \ 1344 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1345} \ 1346static inline void jbd2_clear_feature_##name(journal_t *j) \ 1347{ \ 1348 (j)->j_superblock->s_feature_ro_compat &= \ 1349 ~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1350} 1351 1352#define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \ 1353static inline bool jbd2_has_feature_##name(journal_t *j) \ 1354{ \ 1355 return (jbd2_format_support_feature(j) && \ 1356 ((j)->j_superblock->s_feature_incompat & \ 1357 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \ 1358} \ 1359static inline void jbd2_set_feature_##name(journal_t *j) \ 1360{ \ 1361 (j)->j_superblock->s_feature_incompat |= \ 1362 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1363} \ 1364static inline void jbd2_clear_feature_##name(journal_t *j) \ 1365{ \ 1366 (j)->j_superblock->s_feature_incompat &= \ 1367 ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1368} 1369 1370JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM) 1371 1372JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE) 1373JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT) 1374JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT) 1375JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2) 1376JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3) 1377JBD2_FEATURE_INCOMPAT_FUNCS(fast_commit, FAST_COMMIT) 1378 1379/* Journal high priority write IO operation flags */ 1380#define JBD2_JOURNAL_REQ_FLAGS (REQ_META | REQ_SYNC | REQ_IDLE) 1381 1382/* 1383 * Journal flag definitions 1384 */ 1385#define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */ 1386#define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */ 1387#define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */ 1388#define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */ 1389#define JBD2_LOADED 0x010 /* The journal superblock has been loaded */ 1390#define JBD2_BARRIER 0x020 /* Use IDE barriers */ 1391#define JBD2_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file 1392 * data write error in ordered 1393 * mode */ 1394#define JBD2_CYCLE_RECORD 0x080 /* Journal cycled record log on 1395 * clean and empty filesystem 1396 * logging area */ 1397#define JBD2_FAST_COMMIT_ONGOING 0x100 /* Fast commit is ongoing */ 1398#define JBD2_FULL_COMMIT_ONGOING 0x200 /* Full commit is ongoing */ 1399#define JBD2_JOURNAL_FLUSH_DISCARD 0x0001 1400#define JBD2_JOURNAL_FLUSH_ZEROOUT 0x0002 1401#define JBD2_JOURNAL_FLUSH_VALID (JBD2_JOURNAL_FLUSH_DISCARD | \ 1402 JBD2_JOURNAL_FLUSH_ZEROOUT) 1403 1404/* 1405 * Function declarations for the journaling transaction and buffer 1406 * management 1407 */ 1408 1409/* Filing buffers */ 1410extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *); 1411extern bool __jbd2_journal_refile_buffer(struct journal_head *); 1412extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *); 1413extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1414extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1415static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh) 1416{ 1417 list_add_tail(&bh->b_assoc_buffers, head); 1418} 1419static inline void jbd2_unfile_log_bh(struct buffer_head *bh) 1420{ 1421 list_del_init(&bh->b_assoc_buffers); 1422} 1423 1424/* Log buffer allocation */ 1425struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int); 1426void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *); 1427int jbd2_journal_next_log_block(journal_t *, unsigned long long *); 1428int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, 1429 unsigned long *block); 1430int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1431void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1432 1433/* Commit management */ 1434extern void jbd2_journal_commit_transaction(journal_t *); 1435 1436/* Checkpoint list management */ 1437void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy); 1438unsigned long jbd2_journal_shrink_checkpoint_list(journal_t *journal, unsigned long *nr_to_scan); 1439int __jbd2_journal_remove_checkpoint(struct journal_head *); 1440int jbd2_journal_try_remove_checkpoint(struct journal_head *jh); 1441void jbd2_journal_destroy_checkpoint(journal_t *journal); 1442void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *); 1443 1444 1445/* 1446 * Triggers 1447 */ 1448 1449struct jbd2_buffer_trigger_type { 1450 /* 1451 * Fired a the moment data to write to the journal are known to be 1452 * stable - so either at the moment b_frozen_data is created or just 1453 * before a buffer is written to the journal. mapped_data is a mapped 1454 * buffer that is the frozen data for commit. 1455 */ 1456 void (*t_frozen)(struct jbd2_buffer_trigger_type *type, 1457 struct buffer_head *bh, void *mapped_data, 1458 size_t size); 1459 1460 /* 1461 * Fired during journal abort for dirty buffers that will not be 1462 * committed. 1463 */ 1464 void (*t_abort)(struct jbd2_buffer_trigger_type *type, 1465 struct buffer_head *bh); 1466}; 1467 1468extern void jbd2_buffer_frozen_trigger(struct journal_head *jh, 1469 void *mapped_data, 1470 struct jbd2_buffer_trigger_type *triggers); 1471extern void jbd2_buffer_abort_trigger(struct journal_head *jh, 1472 struct jbd2_buffer_trigger_type *triggers); 1473 1474/* Buffer IO */ 1475extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction, 1476 struct journal_head *jh_in, 1477 struct buffer_head **bh_out, 1478 sector_t blocknr); 1479 1480/* Transaction cache support */ 1481extern void jbd2_journal_destroy_transaction_cache(void); 1482extern int __init jbd2_journal_init_transaction_cache(void); 1483extern void jbd2_journal_free_transaction(transaction_t *); 1484 1485/* 1486 * Journal locking. 1487 * 1488 * We need to lock the journal during transaction state changes so that nobody 1489 * ever tries to take a handle on the running transaction while we are in the 1490 * middle of moving it to the commit phase. j_state_lock does this. 1491 * 1492 * Note that the locking is completely interrupt unsafe. We never touch 1493 * journal structures from interrupts. 1494 */ 1495 1496static inline handle_t *journal_current_handle(void) 1497{ 1498 return current->journal_info; 1499} 1500 1501/* The journaling code user interface: 1502 * 1503 * Create and destroy handles 1504 * Register buffer modifications against the current transaction. 1505 */ 1506 1507extern handle_t *jbd2_journal_start(journal_t *, int nblocks); 1508extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks, 1509 int revoke_records, gfp_t gfp_mask, 1510 unsigned int type, unsigned int line_no); 1511extern int jbd2_journal_restart(handle_t *, int nblocks); 1512extern int jbd2__journal_restart(handle_t *, int nblocks, 1513 int revoke_records, gfp_t gfp_mask); 1514extern int jbd2_journal_start_reserved(handle_t *handle, 1515 unsigned int type, unsigned int line_no); 1516extern void jbd2_journal_free_reserved(handle_t *handle); 1517extern int jbd2_journal_extend(handle_t *handle, int nblocks, 1518 int revoke_records); 1519extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *); 1520extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *); 1521extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *); 1522void jbd2_journal_set_triggers(struct buffer_head *, 1523 struct jbd2_buffer_trigger_type *type); 1524extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *); 1525extern int jbd2_journal_forget (handle_t *, struct buffer_head *); 1526int jbd2_journal_invalidate_folio(journal_t *, struct folio *, 1527 size_t offset, size_t length); 1528bool jbd2_journal_try_to_free_buffers(journal_t *journal, struct folio *folio); 1529extern int jbd2_journal_stop(handle_t *); 1530extern int jbd2_journal_flush(journal_t *journal, unsigned int flags); 1531extern void jbd2_journal_lock_updates (journal_t *); 1532extern void jbd2_journal_unlock_updates (journal_t *); 1533 1534void jbd2_journal_wait_updates(journal_t *); 1535 1536extern journal_t * jbd2_journal_init_dev(struct block_device *bdev, 1537 struct block_device *fs_dev, 1538 unsigned long long start, int len, int bsize); 1539extern journal_t * jbd2_journal_init_inode (struct inode *); 1540extern int jbd2_journal_update_format (journal_t *); 1541extern int jbd2_journal_check_used_features 1542 (journal_t *, unsigned long, unsigned long, unsigned long); 1543extern int jbd2_journal_check_available_features 1544 (journal_t *, unsigned long, unsigned long, unsigned long); 1545extern int jbd2_journal_set_features 1546 (journal_t *, unsigned long, unsigned long, unsigned long); 1547extern void jbd2_journal_clear_features 1548 (journal_t *, unsigned long, unsigned long, unsigned long); 1549extern int jbd2_journal_load (journal_t *journal); 1550extern int jbd2_journal_destroy (journal_t *); 1551extern int jbd2_journal_recover (journal_t *journal); 1552extern int jbd2_journal_wipe (journal_t *, int); 1553extern int jbd2_journal_skip_recovery (journal_t *); 1554extern void jbd2_journal_update_sb_errno(journal_t *); 1555extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t, 1556 unsigned long, blk_opf_t); 1557extern void jbd2_journal_abort (journal_t *, int); 1558extern int jbd2_journal_errno (journal_t *); 1559extern void jbd2_journal_ack_err (journal_t *); 1560extern int jbd2_journal_clear_err (journal_t *); 1561extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *); 1562extern int jbd2_journal_force_commit(journal_t *); 1563extern int jbd2_journal_force_commit_nested(journal_t *); 1564extern int jbd2_journal_inode_ranged_write(handle_t *handle, 1565 struct jbd2_inode *inode, loff_t start_byte, 1566 loff_t length); 1567extern int jbd2_journal_inode_ranged_wait(handle_t *handle, 1568 struct jbd2_inode *inode, loff_t start_byte, 1569 loff_t length); 1570extern int jbd2_journal_finish_inode_data_buffers( 1571 struct jbd2_inode *jinode); 1572extern int jbd2_journal_begin_ordered_truncate(journal_t *journal, 1573 struct jbd2_inode *inode, loff_t new_size); 1574extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode); 1575extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode); 1576 1577/* 1578 * journal_head management 1579 */ 1580struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh); 1581struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh); 1582void jbd2_journal_put_journal_head(struct journal_head *jh); 1583 1584/* 1585 * handle management 1586 */ 1587extern struct kmem_cache *jbd2_handle_cache; 1588 1589static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags) 1590{ 1591 return kmem_cache_zalloc(jbd2_handle_cache, gfp_flags); 1592} 1593 1594static inline void jbd2_free_handle(handle_t *handle) 1595{ 1596 kmem_cache_free(jbd2_handle_cache, handle); 1597} 1598 1599/* 1600 * jbd2_inode management (optional, for those file systems that want to use 1601 * dynamically allocated jbd2_inode structures) 1602 */ 1603extern struct kmem_cache *jbd2_inode_cache; 1604 1605static inline struct jbd2_inode *jbd2_alloc_inode(gfp_t gfp_flags) 1606{ 1607 return kmem_cache_alloc(jbd2_inode_cache, gfp_flags); 1608} 1609 1610static inline void jbd2_free_inode(struct jbd2_inode *jinode) 1611{ 1612 kmem_cache_free(jbd2_inode_cache, jinode); 1613} 1614 1615/* Primary revoke support */ 1616#define JOURNAL_REVOKE_DEFAULT_HASH 256 1617extern int jbd2_journal_init_revoke(journal_t *, int); 1618extern void jbd2_journal_destroy_revoke_record_cache(void); 1619extern void jbd2_journal_destroy_revoke_table_cache(void); 1620extern int __init jbd2_journal_init_revoke_record_cache(void); 1621extern int __init jbd2_journal_init_revoke_table_cache(void); 1622 1623extern void jbd2_journal_destroy_revoke(journal_t *); 1624extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *); 1625extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *); 1626extern void jbd2_journal_write_revoke_records(transaction_t *transaction, 1627 struct list_head *log_bufs); 1628 1629/* Recovery revoke support */ 1630extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t); 1631extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t); 1632extern void jbd2_journal_clear_revoke(journal_t *); 1633extern void jbd2_journal_switch_revoke_table(journal_t *journal); 1634extern void jbd2_clear_buffer_revoked_flags(journal_t *journal); 1635 1636/* 1637 * The log thread user interface: 1638 * 1639 * Request space in the current transaction, and force transaction commit 1640 * transitions on demand. 1641 */ 1642 1643int jbd2_log_start_commit(journal_t *journal, tid_t tid); 1644int jbd2_journal_start_commit(journal_t *journal, tid_t *tid); 1645int jbd2_log_wait_commit(journal_t *journal, tid_t tid); 1646int jbd2_transaction_committed(journal_t *journal, tid_t tid); 1647int jbd2_complete_transaction(journal_t *journal, tid_t tid); 1648int jbd2_log_do_checkpoint(journal_t *journal); 1649int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid); 1650 1651void __jbd2_log_wait_for_space(journal_t *journal); 1652extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *); 1653extern int jbd2_cleanup_journal_tail(journal_t *); 1654 1655/* Fast commit related APIs */ 1656int jbd2_fc_begin_commit(journal_t *journal, tid_t tid); 1657int jbd2_fc_end_commit(journal_t *journal); 1658int jbd2_fc_end_commit_fallback(journal_t *journal); 1659int jbd2_fc_get_buf(journal_t *journal, struct buffer_head **bh_out); 1660int jbd2_submit_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1661int jbd2_wait_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1662int jbd2_fc_wait_bufs(journal_t *journal, int num_blks); 1663int jbd2_fc_release_bufs(journal_t *journal); 1664 1665static inline int jbd2_journal_get_max_txn_bufs(journal_t *journal) 1666{ 1667 return (journal->j_total_len - journal->j_fc_wbufsize) / 4; 1668} 1669 1670/* 1671 * is_journal_abort 1672 * 1673 * Simple test wrapper function to test the JBD2_ABORT state flag. This 1674 * bit, when set, indicates that we have had a fatal error somewhere, 1675 * either inside the journaling layer or indicated to us by the client 1676 * (eg. ext3), and that we and should not commit any further 1677 * transactions. 1678 */ 1679 1680static inline int is_journal_aborted(journal_t *journal) 1681{ 1682 return journal->j_flags & JBD2_ABORT; 1683} 1684 1685static inline int is_handle_aborted(handle_t *handle) 1686{ 1687 if (handle->h_aborted || !handle->h_transaction) 1688 return 1; 1689 return is_journal_aborted(handle->h_transaction->t_journal); 1690} 1691 1692static inline void jbd2_journal_abort_handle(handle_t *handle) 1693{ 1694 handle->h_aborted = 1; 1695} 1696 1697static inline void jbd2_init_fs_dev_write_error(journal_t *journal) 1698{ 1699 struct address_space *mapping = journal->j_fs_dev->bd_inode->i_mapping; 1700 1701 /* 1702 * Save the original wb_err value of client fs's bdev mapping which 1703 * could be used to detect the client fs's metadata async write error. 1704 */ 1705 errseq_check_and_advance(&mapping->wb_err, &journal->j_fs_dev_wb_err); 1706} 1707 1708static inline int jbd2_check_fs_dev_write_error(journal_t *journal) 1709{ 1710 struct address_space *mapping = journal->j_fs_dev->bd_inode->i_mapping; 1711 1712 return errseq_check(&mapping->wb_err, 1713 READ_ONCE(journal->j_fs_dev_wb_err)); 1714} 1715 1716#endif /* __KERNEL__ */ 1717 1718/* Comparison functions for transaction IDs: perform comparisons using 1719 * modulo arithmetic so that they work over sequence number wraps. */ 1720 1721static inline int tid_gt(tid_t x, tid_t y) 1722{ 1723 int difference = (x - y); 1724 return (difference > 0); 1725} 1726 1727static inline int tid_geq(tid_t x, tid_t y) 1728{ 1729 int difference = (x - y); 1730 return (difference >= 0); 1731} 1732 1733extern int jbd2_journal_blocks_per_page(struct inode *inode); 1734extern size_t journal_tag_bytes(journal_t *journal); 1735 1736static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j) 1737{ 1738 return jbd2_has_feature_csum2(j) || jbd2_has_feature_csum3(j); 1739} 1740 1741static inline int jbd2_journal_has_csum_v2or3(journal_t *journal) 1742{ 1743 WARN_ON_ONCE(jbd2_journal_has_csum_v2or3_feature(journal) && 1744 journal->j_chksum_driver == NULL); 1745 1746 return journal->j_chksum_driver != NULL; 1747} 1748 1749static inline int jbd2_journal_get_num_fc_blks(journal_superblock_t *jsb) 1750{ 1751 int num_fc_blocks = be32_to_cpu(jsb->s_num_fc_blks); 1752 1753 return num_fc_blocks ? num_fc_blocks : JBD2_DEFAULT_FAST_COMMIT_BLOCKS; 1754} 1755 1756/* 1757 * Return number of free blocks in the log. Must be called under j_state_lock. 1758 */ 1759static inline unsigned long jbd2_log_space_left(journal_t *journal) 1760{ 1761 /* Allow for rounding errors */ 1762 long free = journal->j_free - 32; 1763 1764 if (journal->j_committing_transaction) { 1765 free -= atomic_read(&journal-> 1766 j_committing_transaction->t_outstanding_credits); 1767 } 1768 return max_t(long, free, 0); 1769} 1770 1771/* 1772 * Definitions which augment the buffer_head layer 1773 */ 1774 1775/* journaling buffer types */ 1776#define BJ_None 0 /* Not journaled */ 1777#define BJ_Metadata 1 /* Normal journaled metadata */ 1778#define BJ_Forget 2 /* Buffer superseded by this transaction */ 1779#define BJ_Shadow 3 /* Buffer contents being shadowed to the log */ 1780#define BJ_Reserved 4 /* Buffer is reserved for access by journal */ 1781#define BJ_Types 5 1782 1783/* JBD uses a CRC32 checksum */ 1784#define JBD_MAX_CHECKSUM_SIZE 4 1785 1786static inline u32 jbd2_chksum(journal_t *journal, u32 crc, 1787 const void *address, unsigned int length) 1788{ 1789 struct { 1790 struct shash_desc shash; 1791 char ctx[JBD_MAX_CHECKSUM_SIZE]; 1792 } desc; 1793 int err; 1794 1795 BUG_ON(crypto_shash_descsize(journal->j_chksum_driver) > 1796 JBD_MAX_CHECKSUM_SIZE); 1797 1798 desc.shash.tfm = journal->j_chksum_driver; 1799 *(u32 *)desc.ctx = crc; 1800 1801 err = crypto_shash_update(&desc.shash, address, length); 1802 BUG_ON(err); 1803 1804 return *(u32 *)desc.ctx; 1805} 1806 1807/* Return most recent uncommitted transaction */ 1808static inline tid_t jbd2_get_latest_transaction(journal_t *journal) 1809{ 1810 tid_t tid; 1811 1812 read_lock(&journal->j_state_lock); 1813 tid = journal->j_commit_request; 1814 if (journal->j_running_transaction) 1815 tid = journal->j_running_transaction->t_tid; 1816 read_unlock(&journal->j_state_lock); 1817 return tid; 1818} 1819 1820static inline int jbd2_handle_buffer_credits(handle_t *handle) 1821{ 1822 journal_t *journal; 1823 1824 if (!handle->h_reserved) 1825 journal = handle->h_transaction->t_journal; 1826 else 1827 journal = handle->h_journal; 1828 1829 return handle->h_total_credits - 1830 DIV_ROUND_UP(handle->h_revoke_credits_requested, 1831 journal->j_revoke_records_per_block); 1832} 1833 1834#ifdef __KERNEL__ 1835 1836#define buffer_trace_init(bh) do {} while (0) 1837#define print_buffer_fields(bh) do {} while (0) 1838#define print_buffer_trace(bh) do {} while (0) 1839#define BUFFER_TRACE(bh, info) do {} while (0) 1840#define BUFFER_TRACE2(bh, bh2, info) do {} while (0) 1841#define JBUFFER_TRACE(jh, info) do {} while (0) 1842 1843#endif /* __KERNEL__ */ 1844 1845#define EFSBADCRC EBADMSG /* Bad CRC detected */ 1846#define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ 1847 1848#endif /* _LINUX_JBD2_H */ 1849