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 <linux/crc32c.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 57 void __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 66 extern void *jbd2_alloc(size_t size, gfp_t flags); 67 extern 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 **/ 91 typedef 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 **/ 105 typedef 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 */ 131 typedef 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 */ 167 struct 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 */ 185 typedef 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; 192 193 typedef 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 */ 202 struct 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 */ 210 typedef 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 */ 226 typedef 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> 304 305 enum 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 }; 318 319 BUFFER_FNS(JBD, jbd) 320 BUFFER_FNS(JWrite, jwrite) 321 BUFFER_FNS(JBDDirty, jbddirty) 322 TAS_BUFFER_FNS(JBDDirty, jbddirty) 323 BUFFER_FNS(Revoked, revoked) 324 TAS_BUFFER_FNS(Revoked, revoked) 325 BUFFER_FNS(RevokeValid, revokevalid) 326 TAS_BUFFER_FNS(RevokeValid, revokevalid) 327 BUFFER_FNS(Freed, freed) 328 BUFFER_FNS(Shadow, shadow) 329 BUFFER_FNS(Verified, verified) 330 331 static inline struct buffer_head *jh2bh(struct journal_head *jh) 332 { 333 return jh->b_bh; 334 } 335 336 static inline struct journal_head *bh2jh(struct buffer_head *bh) 337 { 338 return bh->b_private; 339 } 340 341 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh) 342 { 343 bit_spin_lock(BH_JournalHead, &bh->b_state); 344 } 345 346 static 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 */ 397 struct 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 }; 447 448 struct 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_reserved: Flag for handle for reserved credits. 463 * @h_aborted: Flag indicating fatal error on handle. 464 * @h_type: For handle statistics. 465 * @h_line_no: For handle statistics. 466 * @h_start_jiffies: Handle Start time. 467 * @h_requested_credits: Holds @h_total_credits after handle is started. 468 * @h_revoke_credits_requested: Holds @h_revoke_credits after handle is started. 469 * @saved_alloc_context: Saved context while transaction is open. 470 **/ 471 472 /* Docbook can't yet cope with the bit fields, but will leave the documentation 473 * in so it can be fixed later. 474 */ 475 476 struct jbd2_journal_handle 477 { 478 union { 479 transaction_t *h_transaction; 480 /* Which journal handle belongs to - used iff h_reserved set */ 481 journal_t *h_journal; 482 }; 483 484 handle_t *h_rsv_handle; 485 int h_total_credits; 486 int h_revoke_credits; 487 int h_revoke_credits_requested; 488 int h_ref; 489 int h_err; 490 491 /* Flags [no locking] */ 492 unsigned int h_sync: 1; 493 unsigned int h_reserved: 1; 494 unsigned int h_aborted: 1; 495 unsigned int h_type: 8; 496 unsigned int h_line_no: 16; 497 498 unsigned long h_start_jiffies; 499 unsigned int h_requested_credits; 500 501 unsigned int saved_alloc_context; 502 }; 503 504 505 /* 506 * Some stats for checkpoint phase 507 */ 508 struct transaction_chp_stats_s { 509 unsigned long cs_chp_time; 510 __u32 cs_forced_to_close; 511 __u32 cs_written; 512 __u32 cs_dropped; 513 }; 514 515 /* The transaction_t type is the guts of the journaling mechanism. It 516 * tracks a compound transaction through its various states: 517 * 518 * RUNNING: accepting new updates 519 * LOCKED: Updates still running but we don't accept new ones 520 * RUNDOWN: Updates are tidying up but have finished requesting 521 * new buffers to modify (state not used for now) 522 * FLUSH: All updates complete, but we are still writing to disk 523 * COMMIT: All data on disk, writing commit record 524 * FINISHED: We still have to keep the transaction for checkpointing. 525 * 526 * The transaction keeps track of all of the buffers modified by a 527 * running transaction, and all of the buffers committed but not yet 528 * flushed to home for finished transactions. 529 * (Locking Documentation improved by LockDoc) 530 */ 531 532 /* 533 * Lock ranking: 534 * 535 * j_list_lock 536 * ->jbd_lock_bh_journal_head() (This is "innermost") 537 * 538 * j_state_lock 539 * ->b_state_lock 540 * 541 * b_state_lock 542 * ->j_list_lock 543 * 544 * j_state_lock 545 * ->j_list_lock (journal_unmap_buffer) 546 * 547 */ 548 549 struct transaction_s 550 { 551 /* Pointer to the journal for this transaction. [no locking] */ 552 journal_t *t_journal; 553 554 /* Sequence number for this transaction [no locking] */ 555 tid_t t_tid; 556 557 /* 558 * Transaction's current state 559 * [no locking - only kjournald2 alters this] 560 * [j_list_lock] guards transition of a transaction into T_FINISHED 561 * state and subsequent call of __jbd2_journal_drop_transaction() 562 * FIXME: needs barriers 563 * KLUDGE: [use j_state_lock] 564 */ 565 enum { 566 T_RUNNING, 567 T_LOCKED, 568 T_SWITCH, 569 T_FLUSH, 570 T_COMMIT, 571 T_COMMIT_DFLUSH, 572 T_COMMIT_JFLUSH, 573 T_COMMIT_CALLBACK, 574 T_FINISHED 575 } t_state; 576 577 /* 578 * Where in the log does this transaction's commit start? [no locking] 579 */ 580 unsigned long t_log_start; 581 582 /* 583 * Number of buffers on the t_buffers list [j_list_lock, no locks 584 * needed for jbd2 thread] 585 */ 586 int t_nr_buffers; 587 588 /* 589 * Doubly-linked circular list of all buffers reserved but not yet 590 * modified by this transaction [j_list_lock, no locks needed fo 591 * jbd2 thread] 592 */ 593 struct journal_head *t_reserved_list; 594 595 /* 596 * Doubly-linked circular list of all metadata buffers owned by this 597 * transaction [j_list_lock, no locks needed for jbd2 thread] 598 */ 599 struct journal_head *t_buffers; 600 601 /* 602 * Doubly-linked circular list of all forget buffers (superseded 603 * buffers which we can un-checkpoint once this transaction commits) 604 * [j_list_lock] 605 */ 606 struct journal_head *t_forget; 607 608 /* 609 * Doubly-linked circular list of all buffers still to be flushed before 610 * this transaction can be checkpointed. [j_list_lock] 611 */ 612 struct journal_head *t_checkpoint_list; 613 614 /* 615 * Doubly-linked circular list of metadata buffers being 616 * shadowed by log IO. The IO buffers on the iobuf list and 617 * the shadow buffers on this list match each other one for 618 * one at all times. [j_list_lock, no locks needed for jbd2 619 * thread] 620 */ 621 struct journal_head *t_shadow_list; 622 623 /* 624 * List of inodes associated with the transaction; e.g., ext4 uses 625 * this to track inodes in data=ordered and data=journal mode that 626 * need special handling on transaction commit; also used by ocfs2. 627 * [j_list_lock] 628 */ 629 struct list_head t_inode_list; 630 631 /* 632 * Longest time some handle had to wait for running transaction 633 */ 634 unsigned long t_max_wait; 635 636 /* 637 * When transaction started 638 */ 639 unsigned long t_start; 640 641 /* 642 * When commit was requested [j_state_lock] 643 */ 644 unsigned long t_requested; 645 646 /* 647 * Checkpointing stats [j_list_lock] 648 */ 649 struct transaction_chp_stats_s t_chp_stats; 650 651 /* 652 * Number of outstanding updates running on this transaction 653 * [none] 654 */ 655 atomic_t t_updates; 656 657 /* 658 * Number of blocks reserved for this transaction in the journal. 659 * This is including all credits reserved when starting transaction 660 * handles as well as all journal descriptor blocks needed for this 661 * transaction. [none] 662 */ 663 atomic_t t_outstanding_credits; 664 665 /* 666 * Number of revoke records for this transaction added by already 667 * stopped handles. [none] 668 */ 669 atomic_t t_outstanding_revokes; 670 671 /* 672 * How many handles used this transaction? [none] 673 */ 674 atomic_t t_handle_count; 675 676 /* 677 * Forward and backward links for the circular list of all transactions 678 * awaiting checkpoint. [j_list_lock] 679 */ 680 transaction_t *t_cpnext, *t_cpprev; 681 682 /* 683 * When will the transaction expire (become due for commit), in jiffies? 684 * [no locking] 685 */ 686 unsigned long t_expires; 687 688 /* 689 * When this transaction started, in nanoseconds [no locking] 690 */ 691 ktime_t t_start_time; 692 693 /* 694 * This transaction is being forced and some process is 695 * waiting for it to finish. 696 */ 697 unsigned int t_synchronous_commit:1; 698 699 /* Disk flush needs to be sent to fs partition [no locking] */ 700 int t_need_data_flush; 701 }; 702 703 struct transaction_run_stats_s { 704 unsigned long rs_wait; 705 unsigned long rs_request_delay; 706 unsigned long rs_running; 707 unsigned long rs_locked; 708 unsigned long rs_flushing; 709 unsigned long rs_logging; 710 711 __u32 rs_handle_count; 712 __u32 rs_blocks; 713 __u32 rs_blocks_logged; 714 }; 715 716 struct transaction_stats_s { 717 unsigned long ts_tid; 718 unsigned long ts_requested; 719 struct transaction_run_stats_s run; 720 }; 721 722 static inline unsigned long 723 jbd2_time_diff(unsigned long start, unsigned long end) 724 { 725 if (end >= start) 726 return end - start; 727 728 return end + (MAX_JIFFY_OFFSET - start); 729 } 730 731 #define JBD2_NR_BATCH 64 732 733 enum passtype {PASS_SCAN, PASS_REVOKE, PASS_REPLAY}; 734 735 #define JBD2_FC_REPLAY_STOP 0 736 #define JBD2_FC_REPLAY_CONTINUE 1 737 738 /** 739 * struct journal_s - The journal_s type is the concrete type associated with 740 * journal_t. 741 */ 742 struct journal_s 743 { 744 /** 745 * @j_flags: General journaling state flags [j_state_lock, 746 * no lock for quick racy checks] 747 */ 748 unsigned long j_flags; 749 750 /** 751 * @j_errno: 752 * 753 * Is there an outstanding uncleared error on the journal (from a prior 754 * abort)? [j_state_lock] 755 */ 756 int j_errno; 757 758 /** 759 * @j_abort_mutex: Lock the whole aborting procedure. 760 */ 761 struct mutex j_abort_mutex; 762 763 /** 764 * @j_sb_buffer: The first part of the superblock buffer. 765 */ 766 struct buffer_head *j_sb_buffer; 767 768 /** 769 * @j_superblock: The second part of the superblock buffer. 770 */ 771 journal_superblock_t *j_superblock; 772 773 /** 774 * @j_state_lock: Protect the various scalars in the journal. 775 */ 776 rwlock_t j_state_lock; 777 778 /** 779 * @j_barrier_count: 780 * 781 * Number of processes waiting to create a barrier lock [j_state_lock, 782 * no lock for quick racy checks] 783 */ 784 int j_barrier_count; 785 786 /** 787 * @j_barrier: The barrier lock itself. 788 */ 789 struct mutex j_barrier; 790 791 /** 792 * @j_running_transaction: 793 * 794 * Transactions: The current running transaction... 795 * [j_state_lock, no lock for quick racy checks] [caller holding 796 * open handle] 797 */ 798 transaction_t *j_running_transaction; 799 800 /** 801 * @j_committing_transaction: 802 * 803 * the transaction we are pushing to disk 804 * [j_state_lock] [caller holding open handle] 805 */ 806 transaction_t *j_committing_transaction; 807 808 /** 809 * @j_checkpoint_transactions: 810 * 811 * ... and a linked circular list of all transactions waiting for 812 * checkpointing. [j_list_lock] 813 */ 814 transaction_t *j_checkpoint_transactions; 815 816 /** 817 * @j_wait_transaction_locked: 818 * 819 * Wait queue for waiting for a locked transaction to start committing, 820 * or for a barrier lock to be released. 821 */ 822 wait_queue_head_t j_wait_transaction_locked; 823 824 /** 825 * @j_wait_done_commit: Wait queue for waiting for commit to complete. 826 */ 827 wait_queue_head_t j_wait_done_commit; 828 829 /** 830 * @j_wait_commit: Wait queue to trigger commit. 831 */ 832 wait_queue_head_t j_wait_commit; 833 834 /** 835 * @j_wait_updates: Wait queue to wait for updates to complete. 836 */ 837 wait_queue_head_t j_wait_updates; 838 839 /** 840 * @j_wait_reserved: 841 * 842 * Wait queue to wait for reserved buffer credits to drop. 843 */ 844 wait_queue_head_t j_wait_reserved; 845 846 /** 847 * @j_fc_wait: 848 * 849 * Wait queue to wait for completion of async fast commits. 850 */ 851 wait_queue_head_t j_fc_wait; 852 853 /** 854 * @j_checkpoint_mutex: 855 * 856 * Semaphore for locking against concurrent checkpoints. 857 */ 858 struct mutex j_checkpoint_mutex; 859 860 /** 861 * @j_chkpt_bhs: 862 * 863 * List of buffer heads used by the checkpoint routine. This 864 * was moved from jbd2_log_do_checkpoint() to reduce stack 865 * usage. Access to this array is controlled by the 866 * @j_checkpoint_mutex. [j_checkpoint_mutex] 867 */ 868 struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH]; 869 870 /** 871 * @j_shrinker: 872 * 873 * Journal head shrinker, reclaim buffer's journal head which 874 * has been written back. 875 */ 876 struct shrinker *j_shrinker; 877 878 /** 879 * @j_checkpoint_jh_count: 880 * 881 * Number of journal buffers on the checkpoint list. [j_list_lock] 882 */ 883 struct percpu_counter j_checkpoint_jh_count; 884 885 /** 886 * @j_shrink_transaction: 887 * 888 * Record next transaction will shrink on the checkpoint list. 889 * [j_list_lock] 890 */ 891 transaction_t *j_shrink_transaction; 892 893 /** 894 * @j_head: 895 * 896 * Journal head: identifies the first unused block in the journal. 897 * [j_state_lock] 898 */ 899 unsigned long j_head; 900 901 /** 902 * @j_tail: 903 * 904 * Journal tail: identifies the oldest still-used block in the journal. 905 * [j_state_lock] 906 */ 907 unsigned long j_tail; 908 909 /** 910 * @j_free: 911 * 912 * Journal free: how many free blocks are there in the journal? 913 * [j_state_lock] 914 */ 915 unsigned long j_free; 916 917 /** 918 * @j_first: 919 * 920 * The block number of the first usable block in the journal 921 * [j_state_lock]. 922 */ 923 unsigned long j_first; 924 925 /** 926 * @j_last: 927 * 928 * The block number one beyond the last usable block in the journal 929 * [j_state_lock]. 930 */ 931 unsigned long j_last; 932 933 /** 934 * @j_fc_first: 935 * 936 * The block number of the first fast commit block in the journal 937 * [j_state_lock]. 938 */ 939 unsigned long j_fc_first; 940 941 /** 942 * @j_fc_off: 943 * 944 * Number of fast commit blocks currently allocated. Accessed only 945 * during fast commit. Currently only process can do fast commit, so 946 * this field is not protected by any lock. 947 */ 948 unsigned long j_fc_off; 949 950 /** 951 * @j_fc_last: 952 * 953 * The block number one beyond the last fast commit block in the journal 954 * [j_state_lock]. 955 */ 956 unsigned long j_fc_last; 957 958 /** 959 * @j_dev: Device where we store the journal. 960 */ 961 struct block_device *j_dev; 962 963 /** 964 * @j_blocksize: Block size for the location where we store the journal. 965 */ 966 int j_blocksize; 967 968 /** 969 * @j_blk_offset: 970 * 971 * Starting block offset into the device where we store the journal. 972 */ 973 unsigned long long j_blk_offset; 974 975 /** 976 * @j_devname: Journal device name. 977 */ 978 char j_devname[BDEVNAME_SIZE+24]; 979 980 /** 981 * @j_fs_dev: 982 * 983 * Device which holds the client fs. For internal journal this will be 984 * equal to j_dev. 985 */ 986 struct block_device *j_fs_dev; 987 988 /** 989 * @j_fs_dev_wb_err: 990 * 991 * Records the errseq of the client fs's backing block device. 992 */ 993 errseq_t j_fs_dev_wb_err; 994 995 /** 996 * @j_total_len: Total maximum capacity of the journal region on disk. 997 */ 998 unsigned int j_total_len; 999 1000 /** 1001 * @j_reserved_credits: 1002 * 1003 * Number of buffers reserved from the running transaction. 1004 */ 1005 atomic_t j_reserved_credits; 1006 1007 /** 1008 * @j_list_lock: Protects the buffer lists and internal buffer state. 1009 */ 1010 spinlock_t j_list_lock; 1011 1012 /** 1013 * @j_inode: 1014 * 1015 * Optional inode where we store the journal. If present, all 1016 * journal block numbers are mapped into this inode via bmap(). 1017 */ 1018 struct inode *j_inode; 1019 1020 /** 1021 * @j_tail_sequence: 1022 * 1023 * Sequence number of the oldest transaction in the log [j_state_lock] 1024 */ 1025 tid_t j_tail_sequence; 1026 1027 /** 1028 * @j_transaction_sequence: 1029 * 1030 * Sequence number of the next transaction to grant [j_state_lock] 1031 */ 1032 tid_t j_transaction_sequence; 1033 1034 /** 1035 * @j_commit_sequence: 1036 * 1037 * Sequence number of the most recently committed transaction 1038 * [j_state_lock, no lock for quick racy checks] 1039 */ 1040 tid_t j_commit_sequence; 1041 1042 /** 1043 * @j_commit_request: 1044 * 1045 * Sequence number of the most recent transaction wanting commit 1046 * [j_state_lock, no lock for quick racy checks] 1047 */ 1048 tid_t j_commit_request; 1049 1050 /** 1051 * @j_uuid: 1052 * 1053 * Journal uuid: identifies the object (filesystem, LVM volume etc) 1054 * backed by this journal. This will eventually be replaced by an array 1055 * of uuids, allowing us to index multiple devices within a single 1056 * journal and to perform atomic updates across them. 1057 */ 1058 __u8 j_uuid[16]; 1059 1060 /** 1061 * @j_task: Pointer to the current commit thread for this journal. 1062 */ 1063 struct task_struct *j_task; 1064 1065 /** 1066 * @j_max_transaction_buffers: 1067 * 1068 * Maximum number of metadata buffers to allow in a single compound 1069 * commit transaction. 1070 */ 1071 int j_max_transaction_buffers; 1072 1073 /** 1074 * @j_revoke_records_per_block: 1075 * 1076 * Number of revoke records that fit in one descriptor block. 1077 */ 1078 int j_revoke_records_per_block; 1079 1080 /** 1081 * @j_transaction_overhead_buffers: 1082 * 1083 * Number of blocks each transaction needs for its own bookkeeping 1084 */ 1085 int j_transaction_overhead_buffers; 1086 1087 /** 1088 * @j_commit_interval: 1089 * 1090 * What is the maximum transaction lifetime before we begin a commit? 1091 */ 1092 unsigned long j_commit_interval; 1093 1094 /** 1095 * @j_commit_timer: The timer used to wakeup the commit thread. 1096 */ 1097 struct timer_list j_commit_timer; 1098 1099 /** 1100 * @j_revoke_lock: Protect the revoke table. 1101 */ 1102 spinlock_t j_revoke_lock; 1103 1104 /** 1105 * @j_revoke: 1106 * 1107 * The revoke table - maintains the list of revoked blocks in the 1108 * current transaction. 1109 */ 1110 struct jbd2_revoke_table_s *j_revoke; 1111 1112 /** 1113 * @j_revoke_table: Alternate revoke tables for j_revoke. 1114 */ 1115 struct jbd2_revoke_table_s *j_revoke_table[2]; 1116 1117 /** 1118 * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction. 1119 */ 1120 struct buffer_head **j_wbuf; 1121 1122 /** 1123 * @j_fc_wbuf: Array of fast commit bhs for fast commit. Accessed only 1124 * during a fast commit. Currently only process can do fast commit, so 1125 * this field is not protected by any lock. 1126 */ 1127 struct buffer_head **j_fc_wbuf; 1128 1129 /** 1130 * @j_wbufsize: 1131 * 1132 * Size of @j_wbuf array. 1133 */ 1134 int j_wbufsize; 1135 1136 /** 1137 * @j_fc_wbufsize: 1138 * 1139 * Size of @j_fc_wbuf array. 1140 */ 1141 int j_fc_wbufsize; 1142 1143 /** 1144 * @j_last_sync_writer: 1145 * 1146 * The pid of the last person to run a synchronous operation 1147 * through the journal. 1148 */ 1149 pid_t j_last_sync_writer; 1150 1151 /** 1152 * @j_average_commit_time: 1153 * 1154 * The average amount of time in nanoseconds it takes to commit a 1155 * transaction to disk. [j_state_lock] 1156 */ 1157 u64 j_average_commit_time; 1158 1159 /** 1160 * @j_min_batch_time: 1161 * 1162 * Minimum time that we should wait for additional filesystem operations 1163 * to get batched into a synchronous handle in microseconds. 1164 */ 1165 u32 j_min_batch_time; 1166 1167 /** 1168 * @j_max_batch_time: 1169 * 1170 * Maximum time that we should wait for additional filesystem operations 1171 * to get batched into a synchronous handle in microseconds. 1172 */ 1173 u32 j_max_batch_time; 1174 1175 /** 1176 * @j_commit_callback: 1177 * 1178 * This function is called when a transaction is closed. 1179 */ 1180 void (*j_commit_callback)(journal_t *, 1181 transaction_t *); 1182 1183 /** 1184 * @j_submit_inode_data_buffers: 1185 * 1186 * This function is called for all inodes associated with the 1187 * committing transaction marked with JI_WRITE_DATA flag 1188 * before we start to write out the transaction to the journal. 1189 */ 1190 int (*j_submit_inode_data_buffers) 1191 (struct jbd2_inode *); 1192 1193 /** 1194 * @j_finish_inode_data_buffers: 1195 * 1196 * This function is called for all inodes associated with the 1197 * committing transaction marked with JI_WAIT_DATA flag 1198 * after we have written the transaction to the journal 1199 * but before we write out the commit block. 1200 */ 1201 int (*j_finish_inode_data_buffers) 1202 (struct jbd2_inode *); 1203 1204 /* 1205 * Journal statistics 1206 */ 1207 1208 /** 1209 * @j_history_lock: Protect the transactions statistics history. 1210 */ 1211 spinlock_t j_history_lock; 1212 1213 /** 1214 * @j_proc_entry: procfs entry for the jbd statistics directory. 1215 */ 1216 struct proc_dir_entry *j_proc_entry; 1217 1218 /** 1219 * @j_stats: Overall statistics. 1220 */ 1221 struct transaction_stats_s j_stats; 1222 1223 /** 1224 * @j_failed_commit: Failed journal commit ID. 1225 */ 1226 unsigned int j_failed_commit; 1227 1228 /** 1229 * @j_private: 1230 * 1231 * An opaque pointer to fs-private information. ext3 puts its 1232 * superblock pointer here. 1233 */ 1234 void *j_private; 1235 1236 /** 1237 * @j_csum_seed: 1238 * 1239 * Precomputed journal UUID checksum for seeding other checksums. 1240 */ 1241 __u32 j_csum_seed; 1242 1243 #ifdef CONFIG_DEBUG_LOCK_ALLOC 1244 /** 1245 * @j_trans_commit_map: 1246 * 1247 * Lockdep entity to track transaction commit dependencies. Handles 1248 * hold this "lock" for read, when we wait for commit, we acquire the 1249 * "lock" for writing. This matches the properties of jbd2 journalling 1250 * where the running transaction has to wait for all handles to be 1251 * dropped to commit that transaction and also acquiring a handle may 1252 * require transaction commit to finish. 1253 */ 1254 struct lockdep_map j_trans_commit_map; 1255 #endif 1256 1257 /** 1258 * @j_fc_cleanup_callback: 1259 * 1260 * Clean-up after fast commit or full commit. JBD2 calls this function 1261 * after every commit operation. 1262 */ 1263 void (*j_fc_cleanup_callback)(struct journal_s *journal, int full, tid_t tid); 1264 1265 /** 1266 * @j_fc_replay_callback: 1267 * 1268 * File-system specific function that performs replay of a fast 1269 * commit. JBD2 calls this function for each fast commit block found in 1270 * the journal. This function should return JBD2_FC_REPLAY_CONTINUE 1271 * to indicate that the block was processed correctly and more fast 1272 * commit replay should continue. Return value of JBD2_FC_REPLAY_STOP 1273 * indicates the end of replay (no more blocks remaining). A negative 1274 * return value indicates error. 1275 */ 1276 int (*j_fc_replay_callback)(struct journal_s *journal, 1277 struct buffer_head *bh, 1278 enum passtype pass, int off, 1279 tid_t expected_commit_id); 1280 1281 /** 1282 * @j_bmap: 1283 * 1284 * Bmap function that should be used instead of the generic 1285 * VFS bmap function. 1286 */ 1287 int (*j_bmap)(struct journal_s *journal, sector_t *block); 1288 }; 1289 1290 #define jbd2_might_wait_for_commit(j) \ 1291 do { \ 1292 rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \ 1293 rwsem_release(&j->j_trans_commit_map, _THIS_IP_); \ 1294 } while (0) 1295 1296 /* 1297 * We can support any known requested features iff the 1298 * superblock is not in version 1. Otherwise we fail to support any 1299 * extended sb features. 1300 */ 1301 static inline bool jbd2_format_support_feature(journal_t *j) 1302 { 1303 return j->j_superblock->s_header.h_blocktype != 1304 cpu_to_be32(JBD2_SUPERBLOCK_V1); 1305 } 1306 1307 /* journal feature predicate functions */ 1308 #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \ 1309 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1310 { \ 1311 return (jbd2_format_support_feature(j) && \ 1312 ((j)->j_superblock->s_feature_compat & \ 1313 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \ 1314 } \ 1315 static inline void jbd2_set_feature_##name(journal_t *j) \ 1316 { \ 1317 (j)->j_superblock->s_feature_compat |= \ 1318 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1319 } \ 1320 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1321 { \ 1322 (j)->j_superblock->s_feature_compat &= \ 1323 ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1324 } 1325 1326 #define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \ 1327 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1328 { \ 1329 return (jbd2_format_support_feature(j) && \ 1330 ((j)->j_superblock->s_feature_ro_compat & \ 1331 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \ 1332 } \ 1333 static inline void jbd2_set_feature_##name(journal_t *j) \ 1334 { \ 1335 (j)->j_superblock->s_feature_ro_compat |= \ 1336 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1337 } \ 1338 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1339 { \ 1340 (j)->j_superblock->s_feature_ro_compat &= \ 1341 ~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1342 } 1343 1344 #define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \ 1345 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1346 { \ 1347 return (jbd2_format_support_feature(j) && \ 1348 ((j)->j_superblock->s_feature_incompat & \ 1349 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \ 1350 } \ 1351 static inline void jbd2_set_feature_##name(journal_t *j) \ 1352 { \ 1353 (j)->j_superblock->s_feature_incompat |= \ 1354 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1355 } \ 1356 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1357 { \ 1358 (j)->j_superblock->s_feature_incompat &= \ 1359 ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1360 } 1361 1362 JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM) 1363 1364 JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE) 1365 JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT) 1366 JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT) 1367 JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2) 1368 JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3) 1369 JBD2_FEATURE_INCOMPAT_FUNCS(fast_commit, FAST_COMMIT) 1370 1371 /* Journal high priority write IO operation flags */ 1372 #define JBD2_JOURNAL_REQ_FLAGS (REQ_META | REQ_SYNC | REQ_IDLE) 1373 1374 /* 1375 * Journal flag definitions 1376 */ 1377 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */ 1378 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */ 1379 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */ 1380 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */ 1381 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */ 1382 #define JBD2_BARRIER 0x020 /* Use IDE barriers */ 1383 #define JBD2_CYCLE_RECORD 0x080 /* Journal cycled record log on 1384 * clean and empty filesystem 1385 * logging area */ 1386 #define JBD2_FAST_COMMIT_ONGOING 0x100 /* Fast commit is ongoing */ 1387 #define JBD2_FULL_COMMIT_ONGOING 0x200 /* Full commit is ongoing */ 1388 #define JBD2_JOURNAL_FLUSH_DISCARD 0x0001 1389 #define JBD2_JOURNAL_FLUSH_ZEROOUT 0x0002 1390 #define JBD2_JOURNAL_FLUSH_VALID (JBD2_JOURNAL_FLUSH_DISCARD | \ 1391 JBD2_JOURNAL_FLUSH_ZEROOUT) 1392 1393 /* 1394 * Function declarations for the journaling transaction and buffer 1395 * management 1396 */ 1397 1398 /* Filing buffers */ 1399 extern bool __jbd2_journal_refile_buffer(struct journal_head *); 1400 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *); 1401 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1402 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1403 static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh) 1404 { 1405 list_add_tail(&bh->b_assoc_buffers, head); 1406 } 1407 static inline void jbd2_unfile_log_bh(struct buffer_head *bh) 1408 { 1409 list_del_init(&bh->b_assoc_buffers); 1410 } 1411 1412 /* Log buffer allocation */ 1413 struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int); 1414 void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *); 1415 int jbd2_journal_next_log_block(journal_t *, unsigned long long *); 1416 int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, 1417 unsigned long *block); 1418 int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1419 void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1420 1421 /* Commit management */ 1422 extern void jbd2_journal_commit_transaction(journal_t *); 1423 1424 /* Checkpoint list management */ 1425 enum jbd2_shrink_type {JBD2_SHRINK_DESTROY, JBD2_SHRINK_BUSY_STOP, JBD2_SHRINK_BUSY_SKIP}; 1426 1427 void __jbd2_journal_clean_checkpoint_list(journal_t *journal, enum jbd2_shrink_type type); 1428 unsigned long jbd2_journal_shrink_checkpoint_list(journal_t *journal, unsigned long *nr_to_scan); 1429 int __jbd2_journal_remove_checkpoint(struct journal_head *); 1430 int jbd2_journal_try_remove_checkpoint(struct journal_head *jh); 1431 void jbd2_journal_destroy_checkpoint(journal_t *journal); 1432 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *); 1433 1434 1435 /* 1436 * Triggers 1437 */ 1438 1439 struct jbd2_buffer_trigger_type { 1440 /* 1441 * Fired a the moment data to write to the journal are known to be 1442 * stable - so either at the moment b_frozen_data is created or just 1443 * before a buffer is written to the journal. mapped_data is a mapped 1444 * buffer that is the frozen data for commit. 1445 */ 1446 void (*t_frozen)(struct jbd2_buffer_trigger_type *type, 1447 struct buffer_head *bh, void *mapped_data, 1448 size_t size); 1449 1450 /* 1451 * Fired during journal abort for dirty buffers that will not be 1452 * committed. 1453 */ 1454 void (*t_abort)(struct jbd2_buffer_trigger_type *type, 1455 struct buffer_head *bh); 1456 }; 1457 1458 extern void jbd2_buffer_frozen_trigger(struct journal_head *jh, 1459 void *mapped_data, 1460 struct jbd2_buffer_trigger_type *triggers); 1461 extern void jbd2_buffer_abort_trigger(struct journal_head *jh, 1462 struct jbd2_buffer_trigger_type *triggers); 1463 1464 /* Buffer IO */ 1465 extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction, 1466 struct journal_head *jh_in, 1467 struct buffer_head **bh_out, 1468 sector_t blocknr); 1469 1470 /* Transaction cache support */ 1471 extern void jbd2_journal_destroy_transaction_cache(void); 1472 extern int __init jbd2_journal_init_transaction_cache(void); 1473 extern void jbd2_journal_free_transaction(transaction_t *); 1474 1475 /* 1476 * Journal locking. 1477 * 1478 * We need to lock the journal during transaction state changes so that nobody 1479 * ever tries to take a handle on the running transaction while we are in the 1480 * middle of moving it to the commit phase. j_state_lock does this. 1481 * 1482 * Note that the locking is completely interrupt unsafe. We never touch 1483 * journal structures from interrupts. 1484 */ 1485 1486 static inline handle_t *journal_current_handle(void) 1487 { 1488 return current->journal_info; 1489 } 1490 1491 /* The journaling code user interface: 1492 * 1493 * Create and destroy handles 1494 * Register buffer modifications against the current transaction. 1495 */ 1496 1497 extern handle_t *jbd2_journal_start(journal_t *, int nblocks); 1498 extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks, 1499 int revoke_records, gfp_t gfp_mask, 1500 unsigned int type, unsigned int line_no); 1501 extern int jbd2_journal_restart(handle_t *, int nblocks); 1502 extern int jbd2__journal_restart(handle_t *, int nblocks, 1503 int revoke_records, gfp_t gfp_mask); 1504 extern int jbd2_journal_start_reserved(handle_t *handle, 1505 unsigned int type, unsigned int line_no); 1506 extern void jbd2_journal_free_reserved(handle_t *handle); 1507 extern int jbd2_journal_extend(handle_t *handle, int nblocks, 1508 int revoke_records); 1509 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *); 1510 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *); 1511 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *); 1512 void jbd2_journal_set_triggers(struct buffer_head *, 1513 struct jbd2_buffer_trigger_type *type); 1514 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *); 1515 extern int jbd2_journal_forget (handle_t *, struct buffer_head *); 1516 int jbd2_journal_invalidate_folio(journal_t *, struct folio *, 1517 size_t offset, size_t length); 1518 bool jbd2_journal_try_to_free_buffers(journal_t *journal, struct folio *folio); 1519 extern int jbd2_journal_stop(handle_t *); 1520 extern int jbd2_journal_flush(journal_t *journal, unsigned int flags); 1521 extern void jbd2_journal_lock_updates (journal_t *); 1522 extern void jbd2_journal_unlock_updates (journal_t *); 1523 1524 void jbd2_journal_wait_updates(journal_t *); 1525 1526 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev, 1527 struct block_device *fs_dev, 1528 unsigned long long start, int len, int bsize); 1529 extern journal_t * jbd2_journal_init_inode (struct inode *); 1530 extern int jbd2_journal_update_format (journal_t *); 1531 extern int jbd2_journal_check_used_features 1532 (journal_t *, unsigned long, unsigned long, unsigned long); 1533 extern int jbd2_journal_check_available_features 1534 (journal_t *, unsigned long, unsigned long, unsigned long); 1535 extern int jbd2_journal_set_features 1536 (journal_t *, unsigned long, unsigned long, unsigned long); 1537 extern void jbd2_journal_clear_features 1538 (journal_t *, unsigned long, unsigned long, unsigned long); 1539 extern int jbd2_journal_load (journal_t *journal); 1540 extern int jbd2_journal_destroy (journal_t *); 1541 extern int jbd2_journal_recover (journal_t *journal); 1542 extern int jbd2_journal_wipe (journal_t *, int); 1543 extern int jbd2_journal_skip_recovery (journal_t *); 1544 extern void jbd2_journal_update_sb_errno(journal_t *); 1545 extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t, 1546 unsigned long, blk_opf_t); 1547 extern void jbd2_journal_abort (journal_t *, int); 1548 extern int jbd2_journal_errno (journal_t *); 1549 extern void jbd2_journal_ack_err (journal_t *); 1550 extern int jbd2_journal_clear_err (journal_t *); 1551 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *); 1552 extern int jbd2_journal_force_commit(journal_t *); 1553 extern int jbd2_journal_force_commit_nested(journal_t *); 1554 extern int jbd2_journal_inode_ranged_write(handle_t *handle, 1555 struct jbd2_inode *inode, loff_t start_byte, 1556 loff_t length); 1557 extern int jbd2_journal_inode_ranged_wait(handle_t *handle, 1558 struct jbd2_inode *inode, loff_t start_byte, 1559 loff_t length); 1560 extern int jbd2_journal_finish_inode_data_buffers( 1561 struct jbd2_inode *jinode); 1562 extern int jbd2_journal_begin_ordered_truncate(journal_t *journal, 1563 struct jbd2_inode *inode, loff_t new_size); 1564 extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode); 1565 extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode); 1566 1567 /* 1568 * journal_head management 1569 */ 1570 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh); 1571 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh); 1572 void jbd2_journal_put_journal_head(struct journal_head *jh); 1573 1574 /* 1575 * handle management 1576 */ 1577 extern struct kmem_cache *jbd2_handle_cache; 1578 1579 /* 1580 * This specialized allocator has to be a macro for its allocations to be 1581 * accounted separately (to have a separate alloc_tag). The typecast is 1582 * intentional to enforce typesafety. 1583 */ 1584 #define jbd2_alloc_handle(_gfp_flags) \ 1585 ((handle_t *)kmem_cache_zalloc(jbd2_handle_cache, _gfp_flags)) 1586 1587 static inline void jbd2_free_handle(handle_t *handle) 1588 { 1589 kmem_cache_free(jbd2_handle_cache, handle); 1590 } 1591 1592 /* 1593 * jbd2_inode management (optional, for those file systems that want to use 1594 * dynamically allocated jbd2_inode structures) 1595 */ 1596 extern struct kmem_cache *jbd2_inode_cache; 1597 1598 /* 1599 * This specialized allocator has to be a macro for its allocations to be 1600 * accounted separately (to have a separate alloc_tag). The typecast is 1601 * intentional to enforce typesafety. 1602 */ 1603 #define jbd2_alloc_inode(_gfp_flags) \ 1604 ((struct jbd2_inode *)kmem_cache_alloc(jbd2_inode_cache, _gfp_flags)) 1605 1606 static inline void jbd2_free_inode(struct jbd2_inode *jinode) 1607 { 1608 kmem_cache_free(jbd2_inode_cache, jinode); 1609 } 1610 1611 /* Primary revoke support */ 1612 #define JOURNAL_REVOKE_DEFAULT_HASH 256 1613 extern int jbd2_journal_init_revoke(journal_t *, int); 1614 extern void jbd2_journal_destroy_revoke_record_cache(void); 1615 extern void jbd2_journal_destroy_revoke_table_cache(void); 1616 extern int __init jbd2_journal_init_revoke_record_cache(void); 1617 extern int __init jbd2_journal_init_revoke_table_cache(void); 1618 struct jbd2_revoke_table_s *jbd2_journal_init_revoke_table(int hash_size); 1619 void jbd2_journal_destroy_revoke_table(struct jbd2_revoke_table_s *table); 1620 1621 extern void jbd2_journal_destroy_revoke(journal_t *); 1622 extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *); 1623 extern void jbd2_journal_cancel_revoke(handle_t *, struct journal_head *); 1624 extern void jbd2_journal_write_revoke_records(transaction_t *transaction, 1625 struct list_head *log_bufs); 1626 1627 /* Recovery revoke support */ 1628 extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t); 1629 extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t); 1630 extern void jbd2_journal_clear_revoke(journal_t *); 1631 extern void jbd2_journal_switch_revoke_table(journal_t *journal); 1632 extern void jbd2_clear_buffer_revoked_flags(journal_t *journal); 1633 1634 /* 1635 * The log thread user interface: 1636 * 1637 * Request space in the current transaction, and force transaction commit 1638 * transitions on demand. 1639 */ 1640 1641 int jbd2_log_start_commit(journal_t *journal, tid_t tid); 1642 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid); 1643 int jbd2_log_wait_commit(journal_t *journal, tid_t tid); 1644 int jbd2_transaction_committed(journal_t *journal, tid_t tid); 1645 int jbd2_complete_transaction(journal_t *journal, tid_t tid); 1646 int jbd2_log_do_checkpoint(journal_t *journal); 1647 int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid); 1648 1649 void __jbd2_log_wait_for_space(journal_t *journal); 1650 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *); 1651 extern int jbd2_cleanup_journal_tail(journal_t *); 1652 1653 /* Fast commit related APIs */ 1654 int jbd2_fc_begin_commit(journal_t *journal, tid_t tid); 1655 int jbd2_fc_end_commit(journal_t *journal); 1656 int jbd2_fc_end_commit_fallback(journal_t *journal); 1657 int jbd2_fc_get_buf(journal_t *journal, struct buffer_head **bh_out); 1658 int jbd2_submit_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1659 int jbd2_wait_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1660 int jbd2_fc_wait_bufs(journal_t *journal, int num_blks); 1661 void jbd2_fc_release_bufs(journal_t *journal); 1662 1663 /* 1664 * is_journal_abort 1665 * 1666 * Simple test wrapper function to test the JBD2_ABORT state flag. This 1667 * bit, when set, indicates that we have had a fatal error somewhere, 1668 * either inside the journaling layer or indicated to us by the client 1669 * (eg. ext3), and that we and should not commit any further 1670 * transactions. 1671 */ 1672 1673 static inline int is_journal_aborted(journal_t *journal) 1674 { 1675 return journal->j_flags & JBD2_ABORT; 1676 } 1677 1678 static inline int is_handle_aborted(handle_t *handle) 1679 { 1680 if (handle->h_aborted || !handle->h_transaction) 1681 return 1; 1682 return is_journal_aborted(handle->h_transaction->t_journal); 1683 } 1684 1685 static inline void jbd2_journal_abort_handle(handle_t *handle) 1686 { 1687 handle->h_aborted = 1; 1688 } 1689 1690 static inline void jbd2_init_fs_dev_write_error(journal_t *journal) 1691 { 1692 struct address_space *mapping = journal->j_fs_dev->bd_mapping; 1693 1694 /* 1695 * Save the original wb_err value of client fs's bdev mapping which 1696 * could be used to detect the client fs's metadata async write error. 1697 */ 1698 errseq_check_and_advance(&mapping->wb_err, &journal->j_fs_dev_wb_err); 1699 } 1700 1701 static inline int jbd2_check_fs_dev_write_error(journal_t *journal) 1702 { 1703 struct address_space *mapping = journal->j_fs_dev->bd_mapping; 1704 1705 return errseq_check(&mapping->wb_err, 1706 READ_ONCE(journal->j_fs_dev_wb_err)); 1707 } 1708 1709 #endif /* __KERNEL__ */ 1710 1711 /* Comparison functions for transaction IDs: perform comparisons using 1712 * modulo arithmetic so that they work over sequence number wraps. */ 1713 1714 static inline int tid_gt(tid_t x, tid_t y) 1715 { 1716 int difference = (x - y); 1717 return (difference > 0); 1718 } 1719 1720 static inline int tid_geq(tid_t x, tid_t y) 1721 { 1722 int difference = (x - y); 1723 return (difference >= 0); 1724 } 1725 1726 extern int jbd2_journal_blocks_per_page(struct inode *inode); 1727 extern size_t journal_tag_bytes(journal_t *journal); 1728 1729 static inline int jbd2_journal_has_csum_v2or3(journal_t *journal) 1730 { 1731 return jbd2_has_feature_csum2(journal) || 1732 jbd2_has_feature_csum3(journal); 1733 } 1734 1735 static inline int jbd2_journal_get_num_fc_blks(journal_superblock_t *jsb) 1736 { 1737 int num_fc_blocks = be32_to_cpu(jsb->s_num_fc_blks); 1738 1739 return num_fc_blocks ? num_fc_blocks : JBD2_DEFAULT_FAST_COMMIT_BLOCKS; 1740 } 1741 1742 /* 1743 * Return number of free blocks in the log. Must be called under j_state_lock. 1744 */ 1745 static inline unsigned long jbd2_log_space_left(journal_t *journal) 1746 { 1747 /* Allow for rounding errors */ 1748 long free = journal->j_free - 32; 1749 1750 if (journal->j_committing_transaction) { 1751 free -= atomic_read(&journal-> 1752 j_committing_transaction->t_outstanding_credits); 1753 } 1754 return max_t(long, free, 0); 1755 } 1756 1757 /* 1758 * Definitions which augment the buffer_head layer 1759 */ 1760 1761 /* journaling buffer types */ 1762 #define BJ_None 0 /* Not journaled */ 1763 #define BJ_Metadata 1 /* Normal journaled metadata */ 1764 #define BJ_Forget 2 /* Buffer superseded by this transaction */ 1765 #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */ 1766 #define BJ_Reserved 4 /* Buffer is reserved for access by journal */ 1767 #define BJ_Types 5 1768 1769 static inline u32 jbd2_chksum(journal_t *journal, u32 crc, 1770 const void *address, unsigned int length) 1771 { 1772 return crc32c(crc, address, length); 1773 } 1774 1775 /* Return most recent uncommitted transaction */ 1776 static inline tid_t jbd2_get_latest_transaction(journal_t *journal) 1777 { 1778 tid_t tid; 1779 1780 read_lock(&journal->j_state_lock); 1781 tid = journal->j_commit_request; 1782 if (journal->j_running_transaction) 1783 tid = journal->j_running_transaction->t_tid; 1784 read_unlock(&journal->j_state_lock); 1785 return tid; 1786 } 1787 1788 static inline int jbd2_handle_buffer_credits(handle_t *handle) 1789 { 1790 journal_t *journal; 1791 1792 if (!handle->h_reserved) 1793 journal = handle->h_transaction->t_journal; 1794 else 1795 journal = handle->h_journal; 1796 1797 return handle->h_total_credits - 1798 DIV_ROUND_UP(handle->h_revoke_credits_requested, 1799 journal->j_revoke_records_per_block); 1800 } 1801 1802 #ifdef __KERNEL__ 1803 1804 #define buffer_trace_init(bh) do {} while (0) 1805 #define print_buffer_fields(bh) do {} while (0) 1806 #define print_buffer_trace(bh) do {} while (0) 1807 #define BUFFER_TRACE(bh, info) do {} while (0) 1808 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0) 1809 #define JBUFFER_TRACE(jh, info) do {} while (0) 1810 1811 #endif /* __KERNEL__ */ 1812 1813 #define EFSBADCRC EBADMSG /* Bad CRC detected */ 1814 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ 1815 1816 #endif /* _LINUX_JBD2_H */ 1817