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 #define JBD2_MIN_JOURNAL_BLOCKS 1024 67 #define JBD2_DEFAULT_FAST_COMMIT_BLOCKS 256 68 69 #ifdef __KERNEL__ 70 71 /** 72 * typedef handle_t - The handle_t type represents a single atomic update being performed by some process. 73 * 74 * All filesystem modifications made by the process go 75 * through this handle. Recursive operations (such as quota operations) 76 * are gathered into a single update. 77 * 78 * The buffer credits field is used to account for journaled buffers 79 * being modified by the running process. To ensure that there is 80 * enough log space for all outstanding operations, we need to limit the 81 * number of outstanding buffers possible at any time. When the 82 * operation completes, any buffer credits not used are credited back to 83 * the transaction, so that at all times we know how many buffers the 84 * outstanding updates on a transaction might possibly touch. 85 * 86 * This is an opaque datatype. 87 **/ 88 typedef struct jbd2_journal_handle handle_t; /* Atomic operation type */ 89 90 91 /** 92 * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem. 93 * 94 * journal_t is linked to from the fs superblock structure. 95 * 96 * We use the journal_t to keep track of all outstanding transaction 97 * activity on the filesystem, and to manage the state of the log 98 * writing process. 99 * 100 * This is an opaque datatype. 101 **/ 102 typedef struct journal_s journal_t; /* Journal control structure */ 103 #endif 104 105 /* 106 * Internal structures used by the logging mechanism: 107 */ 108 109 #define JBD2_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */ 110 111 /* 112 * On-disk structures 113 */ 114 115 /* 116 * Descriptor block types: 117 */ 118 119 #define JBD2_DESCRIPTOR_BLOCK 1 120 #define JBD2_COMMIT_BLOCK 2 121 #define JBD2_SUPERBLOCK_V1 3 122 #define JBD2_SUPERBLOCK_V2 4 123 #define JBD2_REVOKE_BLOCK 5 124 125 /* 126 * Standard header for all descriptor blocks: 127 */ 128 typedef struct journal_header_s 129 { 130 __be32 h_magic; 131 __be32 h_blocktype; 132 __be32 h_sequence; 133 } journal_header_t; 134 135 /* 136 * Checksum types. 137 */ 138 #define JBD2_CRC32_CHKSUM 1 139 #define JBD2_MD5_CHKSUM 2 140 #define JBD2_SHA1_CHKSUM 3 141 #define JBD2_CRC32C_CHKSUM 4 142 143 #define JBD2_CRC32_CHKSUM_SIZE 4 144 145 #define JBD2_CHECKSUM_BYTES (32 / sizeof(u32)) 146 /* 147 * Commit block header for storing transactional checksums: 148 * 149 * NOTE: If FEATURE_COMPAT_CHECKSUM (checksum v1) is set, the h_chksum* 150 * fields are used to store a checksum of the descriptor and data blocks. 151 * 152 * If FEATURE_INCOMPAT_CSUM_V2 (checksum v2) is set, then the h_chksum 153 * field is used to store crc32c(uuid+commit_block). Each journal metadata 154 * block gets its own checksum, and data block checksums are stored in 155 * journal_block_tag (in the descriptor). The other h_chksum* fields are 156 * not used. 157 * 158 * If FEATURE_INCOMPAT_CSUM_V3 is set, the descriptor block uses 159 * journal_block_tag3_t to store a full 32-bit checksum. Everything else 160 * is the same as v2. 161 * 162 * Checksum v1, v2, and v3 are mutually exclusive features. 163 */ 164 struct commit_header { 165 __be32 h_magic; 166 __be32 h_blocktype; 167 __be32 h_sequence; 168 unsigned char h_chksum_type; 169 unsigned char h_chksum_size; 170 unsigned char h_padding[2]; 171 __be32 h_chksum[JBD2_CHECKSUM_BYTES]; 172 __be64 h_commit_sec; 173 __be32 h_commit_nsec; 174 }; 175 176 /* 177 * The block tag: used to describe a single buffer in the journal. 178 * t_blocknr_high is only used if INCOMPAT_64BIT is set, so this 179 * raw struct shouldn't be used for pointer math or sizeof() - use 180 * journal_tag_bytes(journal) instead to compute this. 181 */ 182 typedef struct journal_block_tag3_s 183 { 184 __be32 t_blocknr; /* The on-disk block number */ 185 __be32 t_flags; /* See below */ 186 __be32 t_blocknr_high; /* most-significant high 32bits. */ 187 __be32 t_checksum; /* crc32c(uuid+seq+block) */ 188 } journal_block_tag3_t; 189 190 typedef struct journal_block_tag_s 191 { 192 __be32 t_blocknr; /* The on-disk block number */ 193 __be16 t_checksum; /* truncated crc32c(uuid+seq+block) */ 194 __be16 t_flags; /* See below */ 195 __be32 t_blocknr_high; /* most-significant high 32bits. */ 196 } journal_block_tag_t; 197 198 /* Tail of descriptor or revoke block, for checksumming */ 199 struct jbd2_journal_block_tail { 200 __be32 t_checksum; /* crc32c(uuid+descr_block) */ 201 }; 202 203 /* 204 * The revoke descriptor: used on disk to describe a series of blocks to 205 * be revoked from the log 206 */ 207 typedef struct jbd2_journal_revoke_header_s 208 { 209 journal_header_t r_header; 210 __be32 r_count; /* Count of bytes used in the block */ 211 } jbd2_journal_revoke_header_t; 212 213 /* Definitions for the journal tag flags word: */ 214 #define JBD2_FLAG_ESCAPE 1 /* on-disk block is escaped */ 215 #define JBD2_FLAG_SAME_UUID 2 /* block has same uuid as previous */ 216 #define JBD2_FLAG_DELETED 4 /* block deleted by this transaction */ 217 #define JBD2_FLAG_LAST_TAG 8 /* last tag in this descriptor block */ 218 219 220 /* 221 * The journal superblock. All fields are in big-endian byte order. 222 */ 223 typedef struct journal_superblock_s 224 { 225 /* 0x0000 */ 226 journal_header_t s_header; 227 228 /* 0x000C */ 229 /* Static information describing the journal */ 230 __be32 s_blocksize; /* journal device blocksize */ 231 __be32 s_maxlen; /* total blocks in journal file */ 232 __be32 s_first; /* first block of log information */ 233 234 /* 0x0018 */ 235 /* Dynamic information describing the current state of the log */ 236 __be32 s_sequence; /* first commit ID expected in log */ 237 __be32 s_start; /* blocknr of start of log */ 238 239 /* 0x0020 */ 240 /* Error value, as set by jbd2_journal_abort(). */ 241 __be32 s_errno; 242 243 /* 0x0024 */ 244 /* Remaining fields are only valid in a version-2 superblock */ 245 __be32 s_feature_compat; /* compatible feature set */ 246 __be32 s_feature_incompat; /* incompatible feature set */ 247 __be32 s_feature_ro_compat; /* readonly-compatible feature set */ 248 /* 0x0030 */ 249 __u8 s_uuid[16]; /* 128-bit uuid for journal */ 250 251 /* 0x0040 */ 252 __be32 s_nr_users; /* Nr of filesystems sharing log */ 253 254 __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/ 255 256 /* 0x0048 */ 257 __be32 s_max_transaction; /* Limit of journal blocks per trans.*/ 258 __be32 s_max_trans_data; /* Limit of data blocks per trans. */ 259 260 /* 0x0050 */ 261 __u8 s_checksum_type; /* checksum type */ 262 __u8 s_padding2[3]; 263 /* 0x0054 */ 264 __be32 s_num_fc_blks; /* Number of fast commit blocks */ 265 __be32 s_head; /* blocknr of head of log, only uptodate 266 * while the filesystem is clean */ 267 /* 0x005C */ 268 __u32 s_padding[40]; 269 __be32 s_checksum; /* crc32c(superblock) */ 270 271 /* 0x0100 */ 272 __u8 s_users[16*48]; /* ids of all fs'es sharing the log */ 273 /* 0x0400 */ 274 } journal_superblock_t; 275 276 #define JBD2_FEATURE_COMPAT_CHECKSUM 0x00000001 277 278 #define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001 279 #define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002 280 #define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT 0x00000004 281 #define JBD2_FEATURE_INCOMPAT_CSUM_V2 0x00000008 282 #define JBD2_FEATURE_INCOMPAT_CSUM_V3 0x00000010 283 #define JBD2_FEATURE_INCOMPAT_FAST_COMMIT 0x00000020 284 285 /* See "journal feature predicate functions" below */ 286 287 /* Features known to this kernel version: */ 288 #define JBD2_KNOWN_COMPAT_FEATURES JBD2_FEATURE_COMPAT_CHECKSUM 289 #define JBD2_KNOWN_ROCOMPAT_FEATURES 0 290 #define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \ 291 JBD2_FEATURE_INCOMPAT_64BIT | \ 292 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | \ 293 JBD2_FEATURE_INCOMPAT_CSUM_V2 | \ 294 JBD2_FEATURE_INCOMPAT_CSUM_V3 | \ 295 JBD2_FEATURE_INCOMPAT_FAST_COMMIT) 296 297 #ifdef __KERNEL__ 298 299 #include <linux/fs.h> 300 #include <linux/sched.h> 301 302 enum jbd_state_bits { 303 BH_JBD /* Has an attached ext3 journal_head */ 304 = BH_PrivateStart, 305 BH_JWrite, /* Being written to log (@@@ DEBUGGING) */ 306 BH_Freed, /* Has been freed (truncated) */ 307 BH_Revoked, /* Has been revoked from the log */ 308 BH_RevokeValid, /* Revoked flag is valid */ 309 BH_JBDDirty, /* Is dirty but journaled */ 310 BH_JournalHead, /* Pins bh->b_private and jh->b_bh */ 311 BH_Shadow, /* IO on shadow buffer is running */ 312 BH_Verified, /* Metadata block has been verified ok */ 313 BH_JBDPrivateStart, /* First bit available for private use by FS */ 314 }; 315 316 BUFFER_FNS(JBD, jbd) 317 BUFFER_FNS(JWrite, jwrite) 318 BUFFER_FNS(JBDDirty, jbddirty) 319 TAS_BUFFER_FNS(JBDDirty, jbddirty) 320 BUFFER_FNS(Revoked, revoked) 321 TAS_BUFFER_FNS(Revoked, revoked) 322 BUFFER_FNS(RevokeValid, revokevalid) 323 TAS_BUFFER_FNS(RevokeValid, revokevalid) 324 BUFFER_FNS(Freed, freed) 325 BUFFER_FNS(Shadow, shadow) 326 BUFFER_FNS(Verified, verified) 327 328 static inline struct buffer_head *jh2bh(struct journal_head *jh) 329 { 330 return jh->b_bh; 331 } 332 333 static inline struct journal_head *bh2jh(struct buffer_head *bh) 334 { 335 return bh->b_private; 336 } 337 338 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh) 339 { 340 bit_spin_lock(BH_JournalHead, &bh->b_state); 341 } 342 343 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh) 344 { 345 bit_spin_unlock(BH_JournalHead, &bh->b_state); 346 } 347 348 #define J_ASSERT(assert) BUG_ON(!(assert)) 349 350 #define J_ASSERT_BH(bh, expr) J_ASSERT(expr) 351 #define J_ASSERT_JH(jh, expr) J_ASSERT(expr) 352 353 #if defined(JBD2_PARANOID_IOFAIL) 354 #define J_EXPECT(expr, why...) J_ASSERT(expr) 355 #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr) 356 #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr) 357 #else 358 #define __journal_expect(expr, why...) \ 359 ({ \ 360 int val = (expr); \ 361 if (!val) { \ 362 printk(KERN_ERR \ 363 "JBD2 unexpected failure: %s: %s;\n", \ 364 __func__, #expr); \ 365 printk(KERN_ERR why "\n"); \ 366 } \ 367 val; \ 368 }) 369 #define J_EXPECT(expr, why...) __journal_expect(expr, ## why) 370 #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why) 371 #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why) 372 #endif 373 374 /* Flags in jbd_inode->i_flags */ 375 #define __JI_COMMIT_RUNNING 0 376 #define __JI_WRITE_DATA 1 377 #define __JI_WAIT_DATA 2 378 379 /* 380 * Commit of the inode data in progress. We use this flag to protect us from 381 * concurrent deletion of inode. We cannot use reference to inode for this 382 * since we cannot afford doing last iput() on behalf of kjournald 383 */ 384 #define JI_COMMIT_RUNNING (1 << __JI_COMMIT_RUNNING) 385 /* Write allocated dirty buffers in this inode before commit */ 386 #define JI_WRITE_DATA (1 << __JI_WRITE_DATA) 387 /* Wait for outstanding data writes for this inode before commit */ 388 #define JI_WAIT_DATA (1 << __JI_WAIT_DATA) 389 390 /** 391 * struct jbd2_inode - The jbd_inode type is the structure linking inodes in 392 * ordered mode present in a transaction so that we can sync them during commit. 393 */ 394 struct jbd2_inode { 395 /** 396 * @i_transaction: 397 * 398 * Which transaction does this inode belong to? Either the running 399 * transaction or the committing one. [j_list_lock] 400 */ 401 transaction_t *i_transaction; 402 403 /** 404 * @i_next_transaction: 405 * 406 * Pointer to the running transaction modifying inode's data in case 407 * there is already a committing transaction touching it. [j_list_lock] 408 */ 409 transaction_t *i_next_transaction; 410 411 /** 412 * @i_list: List of inodes in the i_transaction [j_list_lock] 413 */ 414 struct list_head i_list; 415 416 /** 417 * @i_vfs_inode: 418 * 419 * VFS inode this inode belongs to [constant for lifetime of structure] 420 */ 421 struct inode *i_vfs_inode; 422 423 /** 424 * @i_flags: Flags of inode [j_list_lock] 425 */ 426 unsigned long i_flags; 427 428 /** 429 * @i_dirty_start_page: 430 * 431 * Dirty range start in PAGE_SIZE units. 432 * 433 * The dirty range is empty if @i_dirty_start_page is greater than or 434 * equal to @i_dirty_end_page. 435 * 436 * [j_list_lock] 437 */ 438 pgoff_t i_dirty_start_page; 439 440 /** 441 * @i_dirty_end_page: 442 * 443 * Dirty range end in PAGE_SIZE units (exclusive). 444 * 445 * [j_list_lock] 446 */ 447 pgoff_t i_dirty_end_page; 448 }; 449 450 /* 451 * Lockless readers treat start_page >= end_page as an empty range. 452 * Writers publish a new non-empty range by storing i_dirty_end_page before 453 * i_dirty_start_page. 454 */ 455 static inline bool jbd2_jinode_get_dirty_range(const struct jbd2_inode *jinode, 456 loff_t *start, loff_t *end) 457 { 458 pgoff_t start_page = READ_ONCE(jinode->i_dirty_start_page); 459 pgoff_t end_page = READ_ONCE(jinode->i_dirty_end_page); 460 461 if (start_page >= end_page) 462 return false; 463 464 *start = (loff_t)start_page << PAGE_SHIFT; 465 *end = ((loff_t)end_page << PAGE_SHIFT) - 1; 466 return true; 467 } 468 469 struct jbd2_revoke_table_s; 470 471 /** 472 * struct jbd2_journal_handle - The jbd2_journal_handle type is the concrete 473 * type associated with handle_t. 474 * @h_transaction: Which compound transaction is this update a part of? 475 * @h_journal: Which journal handle belongs to - used iff h_reserved set. 476 * @h_rsv_handle: Handle reserved for finishing the logical operation. 477 * @h_total_credits: Number of remaining buffers we are allowed to add to 478 * journal. These are dirty buffers and revoke descriptor blocks. 479 * @h_revoke_credits: Number of remaining revoke records available for handle 480 * @h_ref: Reference count on this handle. 481 * @h_err: Field for caller's use to track errors through large fs operations. 482 * @h_sync: Flag for sync-on-close. 483 * @h_reserved: Flag for handle for reserved credits. 484 * @h_aborted: Flag indicating fatal error on handle. 485 * @h_type: For handle statistics. 486 * @h_line_no: For handle statistics. 487 * @h_start_jiffies: Handle Start time. 488 * @h_requested_credits: Holds @h_total_credits after handle is started. 489 * @h_revoke_credits_requested: Holds @h_revoke_credits after handle is started. 490 * @saved_alloc_context: Saved context while transaction is open. 491 **/ 492 493 /* Docbook can't yet cope with the bit fields, but will leave the documentation 494 * in so it can be fixed later. 495 */ 496 497 struct jbd2_journal_handle 498 { 499 union { 500 transaction_t *h_transaction; 501 /* Which journal handle belongs to - used iff h_reserved set */ 502 journal_t *h_journal; 503 }; 504 505 handle_t *h_rsv_handle; 506 int h_total_credits; 507 int h_revoke_credits; 508 int h_revoke_credits_requested; 509 int h_ref; 510 int h_err; 511 512 /* Flags [no locking] */ 513 unsigned char h_sync: 1; 514 unsigned char h_reserved: 1; 515 unsigned char h_aborted: 1; 516 unsigned char h_invalid: 1; 517 unsigned char h_type; 518 unsigned short h_line_no; 519 520 unsigned long h_start_jiffies; 521 unsigned int h_requested_credits; 522 523 unsigned int saved_alloc_context; 524 }; 525 526 527 /* 528 * Some stats for checkpoint phase 529 */ 530 struct transaction_chp_stats_s { 531 unsigned long cs_chp_time; 532 __u32 cs_forced_to_close; 533 __u32 cs_written; 534 __u32 cs_dropped; 535 }; 536 537 /* The transaction_t type is the guts of the journaling mechanism. It 538 * tracks a compound transaction through its various states: 539 * 540 * RUNNING: accepting new updates 541 * LOCKED: Updates still running but we don't accept new ones 542 * RUNDOWN: Updates are tidying up but have finished requesting 543 * new buffers to modify (state not used for now) 544 * FLUSH: All updates complete, but we are still writing to disk 545 * COMMIT: All data on disk, writing commit record 546 * FINISHED: We still have to keep the transaction for checkpointing. 547 * 548 * The transaction keeps track of all of the buffers modified by a 549 * running transaction, and all of the buffers committed but not yet 550 * flushed to home for finished transactions. 551 * (Locking Documentation improved by LockDoc) 552 */ 553 554 /* 555 * Lock ranking: 556 * 557 * j_list_lock 558 * ->jbd_lock_bh_journal_head() (This is "innermost") 559 * 560 * j_state_lock 561 * ->b_state_lock 562 * 563 * b_state_lock 564 * ->j_list_lock 565 * 566 * j_state_lock 567 * ->j_list_lock (journal_unmap_buffer) 568 * 569 */ 570 571 struct transaction_s 572 { 573 /* Pointer to the journal for this transaction. [no locking] */ 574 journal_t *t_journal; 575 576 /* Sequence number for this transaction [no locking] */ 577 tid_t t_tid; 578 579 /* 580 * Transaction's current state 581 * [no locking - only kjournald2 alters this] 582 * [j_list_lock] guards transition of a transaction into T_FINISHED 583 * state and subsequent call of __jbd2_journal_drop_transaction() 584 * FIXME: needs barriers 585 * KLUDGE: [use j_state_lock] 586 */ 587 enum { 588 T_RUNNING, 589 T_LOCKED, 590 T_SWITCH, 591 T_FLUSH, 592 T_COMMIT, 593 T_COMMIT_DFLUSH, 594 T_COMMIT_JFLUSH, 595 T_COMMIT_CALLBACK, 596 T_FINISHED 597 } t_state; 598 599 /* 600 * Where in the log does this transaction's commit start? [no locking] 601 */ 602 unsigned long t_log_start; 603 604 /* 605 * Number of buffers on the t_buffers list [j_list_lock, no locks 606 * needed for jbd2 thread] 607 */ 608 int t_nr_buffers; 609 610 /* 611 * Doubly-linked circular list of all buffers reserved but not yet 612 * modified by this transaction [j_list_lock, no locks needed fo 613 * jbd2 thread] 614 */ 615 struct journal_head *t_reserved_list; 616 617 /* 618 * Doubly-linked circular list of all metadata buffers owned by this 619 * transaction [j_list_lock, no locks needed for jbd2 thread] 620 */ 621 struct journal_head *t_buffers; 622 623 /* 624 * Doubly-linked circular list of all forget buffers (superseded 625 * buffers which we can un-checkpoint once this transaction commits) 626 * [j_list_lock] 627 */ 628 struct journal_head *t_forget; 629 630 /* 631 * Doubly-linked circular list of all buffers still to be flushed before 632 * this transaction can be checkpointed. [j_list_lock] 633 */ 634 struct journal_head *t_checkpoint_list; 635 636 /* 637 * Doubly-linked circular list of metadata buffers being 638 * shadowed by log IO. The IO buffers on the iobuf list and 639 * the shadow buffers on this list match each other one for 640 * one at all times. [j_list_lock, no locks needed for jbd2 641 * thread] 642 */ 643 struct journal_head *t_shadow_list; 644 645 /* 646 * List of inodes associated with the transaction; e.g., ext4 uses 647 * this to track inodes in data=ordered and data=journal mode that 648 * need special handling on transaction commit; also used by ocfs2. 649 * [j_list_lock] 650 */ 651 struct list_head t_inode_list; 652 653 /* 654 * Longest time some handle had to wait for running transaction 655 */ 656 unsigned long t_max_wait; 657 658 /* 659 * When transaction started 660 */ 661 unsigned long t_start; 662 663 /* 664 * When commit was requested [j_state_lock] 665 */ 666 unsigned long t_requested; 667 668 /* 669 * Checkpointing stats [j_list_lock] 670 */ 671 struct transaction_chp_stats_s t_chp_stats; 672 673 /* 674 * Number of outstanding updates running on this transaction 675 * [none] 676 */ 677 atomic_t t_updates; 678 679 /* 680 * Number of blocks reserved for this transaction in the journal. 681 * This is including all credits reserved when starting transaction 682 * handles as well as all journal descriptor blocks needed for this 683 * transaction. [none] 684 */ 685 atomic_t t_outstanding_credits; 686 687 /* 688 * Number of revoke records for this transaction added by already 689 * stopped handles. [none] 690 */ 691 atomic_t t_outstanding_revokes; 692 693 /* 694 * How many handles used this transaction? [none] 695 */ 696 atomic_t t_handle_count; 697 698 /* 699 * Forward and backward links for the circular list of all transactions 700 * awaiting checkpoint. [j_list_lock] 701 */ 702 transaction_t *t_cpnext, *t_cpprev; 703 704 /* 705 * When will the transaction expire (become due for commit), in jiffies? 706 * [no locking] 707 */ 708 unsigned long t_expires; 709 710 /* 711 * When this transaction started, in nanoseconds [no locking] 712 */ 713 ktime_t t_start_time; 714 715 /* 716 * This transaction is being forced and some process is 717 * waiting for it to finish. 718 */ 719 unsigned int t_synchronous_commit:1; 720 721 /* Disk flush needs to be sent to fs partition [no locking] */ 722 int t_need_data_flush; 723 }; 724 725 struct transaction_run_stats_s { 726 unsigned long rs_wait; 727 unsigned long rs_request_delay; 728 unsigned long rs_running; 729 unsigned long rs_locked; 730 unsigned long rs_flushing; 731 unsigned long rs_logging; 732 733 __u32 rs_handle_count; 734 __u32 rs_blocks; 735 __u32 rs_blocks_logged; 736 }; 737 738 struct transaction_stats_s { 739 unsigned long ts_tid; 740 unsigned long ts_requested; 741 struct transaction_run_stats_s run; 742 }; 743 744 static inline unsigned long 745 jbd2_time_diff(unsigned long start, unsigned long end) 746 { 747 if (end >= start) 748 return end - start; 749 750 return end + (MAX_JIFFY_OFFSET - start); 751 } 752 753 #define JBD2_NR_BATCH 64 754 755 enum passtype {PASS_SCAN, PASS_REVOKE, PASS_REPLAY}; 756 757 #define JBD2_FC_REPLAY_STOP 0 758 #define JBD2_FC_REPLAY_CONTINUE 1 759 760 /** 761 * struct journal_s - The journal_s type is the concrete type associated with 762 * journal_t. 763 */ 764 struct journal_s 765 { 766 /** 767 * @j_flags: General journaling state flags [j_state_lock, 768 * no lock for quick racy checks] 769 */ 770 unsigned long j_flags; 771 772 /** 773 * @j_errno: 774 * 775 * Is there an outstanding uncleared error on the journal (from a prior 776 * abort)? [j_state_lock] 777 */ 778 int j_errno; 779 780 /** 781 * @j_abort_mutex: Lock the whole aborting procedure. 782 */ 783 struct mutex j_abort_mutex; 784 785 /** 786 * @j_sb_buffer: The first part of the superblock buffer. 787 */ 788 struct buffer_head *j_sb_buffer; 789 790 /** 791 * @j_superblock: The second part of the superblock buffer. 792 */ 793 journal_superblock_t *j_superblock; 794 795 /** 796 * @j_state_lock: Protect the various scalars in the journal. 797 */ 798 rwlock_t j_state_lock ____cacheline_aligned_in_smp; 799 800 /** 801 * @j_barrier_count: 802 * 803 * Number of processes waiting to create a barrier lock [j_state_lock, 804 * no lock for quick racy checks] 805 */ 806 int j_barrier_count; 807 808 /** 809 * @j_barrier: The barrier lock itself. 810 */ 811 struct mutex j_barrier; 812 813 /** 814 * @j_running_transaction: 815 * 816 * Transactions: The current running transaction... 817 * [j_state_lock, no lock for quick racy checks] [caller holding 818 * open handle] 819 */ 820 transaction_t *j_running_transaction; 821 822 /** 823 * @j_committing_transaction: 824 * 825 * the transaction we are pushing to disk 826 * [j_state_lock] [caller holding open handle] 827 */ 828 transaction_t *j_committing_transaction; 829 830 /** 831 * @j_checkpoint_transactions: 832 * 833 * ... and a linked circular list of all transactions waiting for 834 * checkpointing. [j_list_lock] 835 */ 836 transaction_t *j_checkpoint_transactions; 837 838 /** 839 * @j_wait_transaction_locked: 840 * 841 * Wait queue for waiting for a locked transaction to start committing, 842 * or for a barrier lock to be released. 843 */ 844 wait_queue_head_t j_wait_transaction_locked; 845 846 /** 847 * @j_wait_done_commit: Wait queue for waiting for commit to complete. 848 */ 849 wait_queue_head_t j_wait_done_commit; 850 851 /** 852 * @j_wait_commit: Wait queue to trigger commit. 853 */ 854 wait_queue_head_t j_wait_commit; 855 856 /** 857 * @j_wait_updates: Wait queue to wait for updates to complete. 858 */ 859 wait_queue_head_t j_wait_updates; 860 861 /** 862 * @j_wait_reserved: 863 * 864 * Wait queue to wait for reserved buffer credits to drop. 865 */ 866 wait_queue_head_t j_wait_reserved; 867 868 /** 869 * @j_fc_wait: 870 * 871 * Wait queue to wait for completion of async fast commits. 872 */ 873 wait_queue_head_t j_fc_wait; 874 875 /** 876 * @j_checkpoint_mutex: 877 * 878 * Semaphore for locking against concurrent checkpoints. 879 */ 880 struct mutex j_checkpoint_mutex; 881 882 /** 883 * @j_chkpt_bhs: 884 * 885 * List of buffer heads used by the checkpoint routine. This 886 * was moved from jbd2_log_do_checkpoint() to reduce stack 887 * usage. Access to this array is controlled by the 888 * @j_checkpoint_mutex. [j_checkpoint_mutex] 889 */ 890 struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH]; 891 892 /** 893 * @j_shrinker: 894 * 895 * Journal head shrinker, reclaim buffer's journal head which 896 * has been written back. 897 */ 898 struct shrinker *j_shrinker; 899 900 /** 901 * @j_checkpoint_jh_count: 902 * 903 * Number of journal buffers on the checkpoint list. [j_list_lock] 904 */ 905 struct percpu_counter j_checkpoint_jh_count; 906 907 /** 908 * @j_shrink_transaction: 909 * 910 * Record next transaction will shrink on the checkpoint list. 911 * [j_list_lock] 912 */ 913 transaction_t *j_shrink_transaction; 914 915 /** 916 * @j_head: 917 * 918 * Journal head: identifies the first unused block in the journal. 919 * [j_state_lock] 920 */ 921 unsigned long j_head; 922 923 /** 924 * @j_tail: 925 * 926 * Journal tail: identifies the oldest still-used block in the journal. 927 * [j_state_lock] 928 */ 929 unsigned long j_tail; 930 931 /** 932 * @j_free: 933 * 934 * Journal free: how many free blocks are there in the journal? 935 * [j_state_lock] 936 */ 937 unsigned long j_free; 938 939 /** 940 * @j_first: 941 * 942 * The block number of the first usable block in the journal 943 * [j_state_lock]. 944 */ 945 unsigned long j_first; 946 947 /** 948 * @j_last: 949 * 950 * The block number one beyond the last usable block in the journal 951 * [j_state_lock]. 952 */ 953 unsigned long j_last; 954 955 /** 956 * @j_fc_first: 957 * 958 * The block number of the first fast commit block in the journal 959 * [j_state_lock]. 960 */ 961 unsigned long j_fc_first; 962 963 /** 964 * @j_fc_off: 965 * 966 * Number of fast commit blocks currently allocated. Accessed only 967 * during fast commit. Currently only process can do fast commit, so 968 * this field is not protected by any lock. 969 */ 970 unsigned long j_fc_off; 971 972 /** 973 * @j_fc_last: 974 * 975 * The block number one beyond the last fast commit block in the journal 976 * [j_state_lock]. 977 */ 978 unsigned long j_fc_last; 979 980 /** 981 * @j_dev: Device where we store the journal. 982 */ 983 struct block_device *j_dev; 984 985 /** 986 * @j_blocksize: Block size for the location where we store the journal. 987 */ 988 int j_blocksize; 989 990 /** 991 * @j_blk_offset: 992 * 993 * Starting block offset into the device where we store the journal. 994 */ 995 unsigned long long j_blk_offset; 996 997 /** 998 * @j_devname: Journal device name. 999 */ 1000 char j_devname[BDEVNAME_SIZE+24]; 1001 1002 /** 1003 * @j_fs_dev: 1004 * 1005 * Device which holds the client fs. For internal journal this will be 1006 * equal to j_dev. 1007 */ 1008 struct block_device *j_fs_dev; 1009 1010 /** 1011 * @j_fs_dev_wb_err: 1012 * 1013 * Records the errseq of the client fs's backing block device. 1014 */ 1015 errseq_t j_fs_dev_wb_err; 1016 1017 /** 1018 * @j_total_len: Total maximum capacity of the journal region on disk. 1019 */ 1020 unsigned int j_total_len; 1021 1022 /** 1023 * @j_reserved_credits: 1024 * 1025 * Number of buffers reserved from the running transaction. 1026 */ 1027 atomic_t j_reserved_credits; 1028 1029 /** 1030 * @j_list_lock: Protects the buffer lists and internal buffer state. 1031 */ 1032 spinlock_t j_list_lock; 1033 1034 /** 1035 * @j_inode: 1036 * 1037 * Optional inode where we store the journal. If present, all 1038 * journal block numbers are mapped into this inode via bmap(). 1039 */ 1040 struct inode *j_inode; 1041 1042 /** 1043 * @j_tail_sequence: 1044 * 1045 * Sequence number of the oldest transaction in the log [j_state_lock] 1046 */ 1047 tid_t j_tail_sequence; 1048 1049 /** 1050 * @j_transaction_sequence: 1051 * 1052 * Sequence number of the next transaction to grant [j_state_lock] 1053 */ 1054 tid_t j_transaction_sequence; 1055 1056 /** 1057 * @j_commit_sequence: 1058 * 1059 * Sequence number of the most recently committed transaction 1060 * [j_state_lock, no lock for quick racy checks] 1061 */ 1062 tid_t j_commit_sequence; 1063 1064 /** 1065 * @j_commit_request: 1066 * 1067 * Sequence number of the most recent transaction wanting commit 1068 * [j_state_lock, no lock for quick racy checks] 1069 */ 1070 tid_t j_commit_request; 1071 1072 /** 1073 * @j_uuid: 1074 * 1075 * Journal uuid: identifies the object (filesystem, LVM volume etc) 1076 * backed by this journal. This will eventually be replaced by an array 1077 * of uuids, allowing us to index multiple devices within a single 1078 * journal and to perform atomic updates across them. 1079 */ 1080 __u8 j_uuid[16]; 1081 1082 /** 1083 * @j_task: Pointer to the current commit thread for this journal. 1084 */ 1085 struct task_struct *j_task; 1086 1087 /** 1088 * @j_max_transaction_buffers: 1089 * 1090 * Maximum number of metadata buffers to allow in a single compound 1091 * commit transaction. 1092 */ 1093 int j_max_transaction_buffers; 1094 1095 /** 1096 * @j_revoke_records_per_block: 1097 * 1098 * Number of revoke records that fit in one descriptor block. 1099 */ 1100 int j_revoke_records_per_block; 1101 1102 /** 1103 * @j_transaction_overhead_buffers: 1104 * 1105 * Number of blocks each transaction needs for its own bookkeeping 1106 */ 1107 int j_transaction_overhead_buffers; 1108 1109 /** 1110 * @j_commit_interval: 1111 * 1112 * What is the maximum transaction lifetime before we begin a commit? 1113 */ 1114 unsigned long j_commit_interval; 1115 1116 /** 1117 * @j_commit_timer: The timer used to wakeup the commit thread. 1118 */ 1119 struct timer_list j_commit_timer; 1120 1121 /** 1122 * @j_revoke_lock: Protect the revoke table. 1123 */ 1124 spinlock_t j_revoke_lock; 1125 1126 /** 1127 * @j_revoke: 1128 * 1129 * The revoke table - maintains the list of revoked blocks in the 1130 * current transaction. 1131 */ 1132 struct jbd2_revoke_table_s *j_revoke; 1133 1134 /** 1135 * @j_revoke_table: Alternate revoke tables for j_revoke. 1136 */ 1137 struct jbd2_revoke_table_s *j_revoke_table[2]; 1138 1139 /** 1140 * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction. 1141 */ 1142 struct buffer_head **j_wbuf; 1143 1144 /** 1145 * @j_fc_wbuf: Array of fast commit bhs for fast commit. Accessed only 1146 * during a fast commit. Currently only process can do fast commit, so 1147 * this field is not protected by any lock. 1148 */ 1149 struct buffer_head **j_fc_wbuf; 1150 1151 /** 1152 * @j_wbufsize: 1153 * 1154 * Size of @j_wbuf array. 1155 */ 1156 int j_wbufsize; 1157 1158 /** 1159 * @j_fc_wbufsize: 1160 * 1161 * Size of @j_fc_wbuf array. 1162 */ 1163 int j_fc_wbufsize; 1164 1165 /** 1166 * @j_last_sync_writer: 1167 * 1168 * The pid of the last person to run a synchronous operation 1169 * through the journal. 1170 */ 1171 pid_t j_last_sync_writer; 1172 1173 /** 1174 * @j_average_commit_time: 1175 * 1176 * The average amount of time in nanoseconds it takes to commit a 1177 * transaction to disk. [j_state_lock] 1178 */ 1179 u64 j_average_commit_time; 1180 1181 /** 1182 * @j_min_batch_time: 1183 * 1184 * Minimum time that we should wait for additional filesystem operations 1185 * to get batched into a synchronous handle in microseconds. 1186 */ 1187 u32 j_min_batch_time; 1188 1189 /** 1190 * @j_max_batch_time: 1191 * 1192 * Maximum time that we should wait for additional filesystem operations 1193 * to get batched into a synchronous handle in microseconds. 1194 */ 1195 u32 j_max_batch_time; 1196 1197 /** 1198 * @j_commit_callback: 1199 * 1200 * This function is called when a transaction is closed. 1201 */ 1202 void (*j_commit_callback)(journal_t *, 1203 transaction_t *); 1204 1205 /** 1206 * @j_submit_inode_data_buffers: 1207 * 1208 * This function is called for all inodes associated with the 1209 * committing transaction marked with JI_WRITE_DATA flag 1210 * before we start to write out the transaction to the journal. 1211 */ 1212 int (*j_submit_inode_data_buffers) 1213 (struct jbd2_inode *); 1214 1215 /** 1216 * @j_finish_inode_data_buffers: 1217 * 1218 * This function is called for all inodes associated with the 1219 * committing transaction marked with JI_WAIT_DATA flag 1220 * after we have written the transaction to the journal 1221 * but before we write out the commit block. 1222 */ 1223 int (*j_finish_inode_data_buffers) 1224 (struct jbd2_inode *); 1225 1226 /* 1227 * Journal statistics 1228 */ 1229 1230 /** 1231 * @j_history_lock: Protect the transactions statistics history. 1232 */ 1233 spinlock_t j_history_lock; 1234 1235 /** 1236 * @j_proc_entry: procfs entry for the jbd statistics directory. 1237 */ 1238 struct proc_dir_entry *j_proc_entry; 1239 1240 /** 1241 * @j_stats: Overall statistics. 1242 */ 1243 struct transaction_stats_s j_stats; 1244 1245 /** 1246 * @j_failed_commit: Failed journal commit ID. 1247 */ 1248 unsigned int j_failed_commit; 1249 1250 /** 1251 * @j_private: 1252 * 1253 * An opaque pointer to fs-private information. ext3 puts its 1254 * superblock pointer here. 1255 */ 1256 void *j_private; 1257 1258 /** 1259 * @j_csum_seed: 1260 * 1261 * Precomputed journal UUID checksum for seeding other checksums. 1262 */ 1263 __u32 j_csum_seed; 1264 1265 #ifdef CONFIG_DEBUG_LOCK_ALLOC 1266 /** 1267 * @j_trans_commit_map: 1268 * 1269 * Lockdep entity to track transaction commit dependencies. Handles 1270 * hold this "lock" for read, when we wait for commit, we acquire the 1271 * "lock" for writing. This matches the properties of jbd2 journalling 1272 * where the running transaction has to wait for all handles to be 1273 * dropped to commit that transaction and also acquiring a handle may 1274 * require transaction commit to finish. 1275 */ 1276 struct lockdep_map j_trans_commit_map; 1277 #endif 1278 /** 1279 * @jbd2_trans_commit_key: 1280 * 1281 * "struct lock_class_key" for @j_trans_commit_map 1282 */ 1283 struct lock_class_key jbd2_trans_commit_key; 1284 1285 /** 1286 * @j_fc_cleanup_callback: 1287 * 1288 * Clean-up after fast commit or full commit. JBD2 calls this function 1289 * after every commit operation. 1290 */ 1291 void (*j_fc_cleanup_callback)(struct journal_s *journal, int full, tid_t tid); 1292 1293 /** 1294 * @j_fc_replay_callback: 1295 * 1296 * File-system specific function that performs replay of a fast 1297 * commit. JBD2 calls this function for each fast commit block found in 1298 * the journal. This function should return JBD2_FC_REPLAY_CONTINUE 1299 * to indicate that the block was processed correctly and more fast 1300 * commit replay should continue. Return value of JBD2_FC_REPLAY_STOP 1301 * indicates the end of replay (no more blocks remaining). A negative 1302 * return value indicates error. 1303 */ 1304 int (*j_fc_replay_callback)(struct journal_s *journal, 1305 struct buffer_head *bh, 1306 enum passtype pass, int off, 1307 tid_t expected_commit_id); 1308 1309 /** 1310 * @j_bmap: 1311 * 1312 * Bmap function that should be used instead of the generic 1313 * VFS bmap function. 1314 */ 1315 int (*j_bmap)(struct journal_s *journal, sector_t *block); 1316 }; 1317 1318 #define jbd2_might_wait_for_commit(j) \ 1319 do { \ 1320 rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \ 1321 rwsem_release(&j->j_trans_commit_map, _THIS_IP_); \ 1322 } while (0) 1323 1324 /* 1325 * We can support any known requested features iff the 1326 * superblock is not in version 1. Otherwise we fail to support any 1327 * extended sb features. 1328 */ 1329 static inline bool jbd2_format_support_feature(journal_t *j) 1330 { 1331 return j->j_superblock->s_header.h_blocktype != 1332 cpu_to_be32(JBD2_SUPERBLOCK_V1); 1333 } 1334 1335 /* journal feature predicate functions */ 1336 #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \ 1337 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1338 { \ 1339 return (jbd2_format_support_feature(j) && \ 1340 ((j)->j_superblock->s_feature_compat & \ 1341 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \ 1342 } \ 1343 static inline void jbd2_set_feature_##name(journal_t *j) \ 1344 { \ 1345 (j)->j_superblock->s_feature_compat |= \ 1346 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1347 } \ 1348 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1349 { \ 1350 (j)->j_superblock->s_feature_compat &= \ 1351 ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1352 } 1353 1354 #define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \ 1355 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1356 { \ 1357 return (jbd2_format_support_feature(j) && \ 1358 ((j)->j_superblock->s_feature_ro_compat & \ 1359 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \ 1360 } \ 1361 static inline void jbd2_set_feature_##name(journal_t *j) \ 1362 { \ 1363 (j)->j_superblock->s_feature_ro_compat |= \ 1364 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1365 } \ 1366 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1367 { \ 1368 (j)->j_superblock->s_feature_ro_compat &= \ 1369 ~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1370 } 1371 1372 #define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \ 1373 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1374 { \ 1375 return (jbd2_format_support_feature(j) && \ 1376 ((j)->j_superblock->s_feature_incompat & \ 1377 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \ 1378 } \ 1379 static inline void jbd2_set_feature_##name(journal_t *j) \ 1380 { \ 1381 (j)->j_superblock->s_feature_incompat |= \ 1382 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1383 } \ 1384 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1385 { \ 1386 (j)->j_superblock->s_feature_incompat &= \ 1387 ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1388 } 1389 1390 JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM) 1391 1392 JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE) 1393 JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT) 1394 JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT) 1395 JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2) 1396 JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3) 1397 JBD2_FEATURE_INCOMPAT_FUNCS(fast_commit, FAST_COMMIT) 1398 1399 /* Journal high priority write IO operation flags */ 1400 #define JBD2_JOURNAL_REQ_FLAGS (REQ_META | REQ_SYNC | REQ_IDLE) 1401 1402 /* 1403 * Journal flag definitions 1404 */ 1405 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */ 1406 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */ 1407 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */ 1408 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */ 1409 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */ 1410 #define JBD2_BARRIER 0x020 /* Use IDE barriers */ 1411 #define JBD2_CYCLE_RECORD 0x080 /* Journal cycled record log on 1412 * clean and empty filesystem 1413 * logging area */ 1414 #define JBD2_FAST_COMMIT_ONGOING 0x100 /* Fast commit is ongoing */ 1415 #define JBD2_FULL_COMMIT_ONGOING 0x200 /* Full commit is ongoing */ 1416 #define JBD2_JOURNAL_FLUSH_DISCARD 0x0001 1417 #define JBD2_JOURNAL_FLUSH_ZEROOUT 0x0002 1418 #define JBD2_JOURNAL_FLUSH_VALID (JBD2_JOURNAL_FLUSH_DISCARD | \ 1419 JBD2_JOURNAL_FLUSH_ZEROOUT) 1420 1421 /* 1422 * Function declarations for the journaling transaction and buffer 1423 * management 1424 */ 1425 1426 /* Filing buffers */ 1427 extern bool __jbd2_journal_refile_buffer(struct journal_head *); 1428 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *); 1429 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1430 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1431 static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh) 1432 { 1433 list_add_tail(&bh->b_assoc_buffers, head); 1434 } 1435 static inline void jbd2_unfile_log_bh(struct buffer_head *bh) 1436 { 1437 list_del_init(&bh->b_assoc_buffers); 1438 } 1439 1440 /* Log buffer allocation */ 1441 struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int); 1442 void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *); 1443 int jbd2_journal_next_log_block(journal_t *, unsigned long long *); 1444 int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, 1445 unsigned long *block); 1446 int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1447 void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1448 1449 /* Commit management */ 1450 extern void jbd2_journal_commit_transaction(journal_t *); 1451 1452 /* Checkpoint list management */ 1453 enum jbd2_shrink_type {JBD2_SHRINK_DESTROY, JBD2_SHRINK_BUSY_STOP, JBD2_SHRINK_BUSY_SKIP}; 1454 1455 void __jbd2_journal_clean_checkpoint_list(journal_t *journal, enum jbd2_shrink_type type); 1456 unsigned long jbd2_journal_shrink_checkpoint_list(journal_t *journal, unsigned long *nr_to_scan); 1457 int __jbd2_journal_remove_checkpoint(struct journal_head *); 1458 int jbd2_journal_try_remove_checkpoint(struct journal_head *jh); 1459 void jbd2_journal_destroy_checkpoint(journal_t *journal); 1460 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *); 1461 1462 1463 /* 1464 * Triggers 1465 */ 1466 1467 struct jbd2_buffer_trigger_type { 1468 /* 1469 * Fired a the moment data to write to the journal are known to be 1470 * stable - so either at the moment b_frozen_data is created or just 1471 * before a buffer is written to the journal. mapped_data is a mapped 1472 * buffer that is the frozen data for commit. 1473 */ 1474 void (*t_frozen)(struct jbd2_buffer_trigger_type *type, 1475 struct buffer_head *bh, void *mapped_data, 1476 size_t size); 1477 1478 /* 1479 * Fired during journal abort for dirty buffers that will not be 1480 * committed. 1481 */ 1482 void (*t_abort)(struct jbd2_buffer_trigger_type *type, 1483 struct buffer_head *bh); 1484 }; 1485 1486 extern void jbd2_buffer_frozen_trigger(struct journal_head *jh, 1487 void *mapped_data, 1488 struct jbd2_buffer_trigger_type *triggers); 1489 extern void jbd2_buffer_abort_trigger(struct journal_head *jh, 1490 struct jbd2_buffer_trigger_type *triggers); 1491 1492 /* Buffer IO */ 1493 extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction, 1494 struct journal_head *jh_in, 1495 struct buffer_head **bh_out, 1496 sector_t blocknr); 1497 1498 /* Transaction cache support */ 1499 extern void jbd2_journal_destroy_transaction_cache(void); 1500 extern int __init jbd2_journal_init_transaction_cache(void); 1501 extern void jbd2_journal_free_transaction(transaction_t *); 1502 1503 /* 1504 * Journal locking. 1505 * 1506 * We need to lock the journal during transaction state changes so that nobody 1507 * ever tries to take a handle on the running transaction while we are in the 1508 * middle of moving it to the commit phase. j_state_lock does this. 1509 * 1510 * Note that the locking is completely interrupt unsafe. We never touch 1511 * journal structures from interrupts. 1512 */ 1513 1514 static inline handle_t *journal_current_handle(void) 1515 { 1516 return current->journal_info; 1517 } 1518 1519 /* The journaling code user interface: 1520 * 1521 * Create and destroy handles 1522 * Register buffer modifications against the current transaction. 1523 */ 1524 1525 extern handle_t *jbd2_journal_start(journal_t *, int nblocks); 1526 extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks, 1527 int revoke_records, gfp_t gfp_mask, 1528 unsigned int type, unsigned int line_no); 1529 extern int jbd2_journal_restart(handle_t *, int nblocks); 1530 extern int jbd2__journal_restart(handle_t *, int nblocks, 1531 int revoke_records, gfp_t gfp_mask); 1532 extern int jbd2_journal_start_reserved(handle_t *handle, 1533 unsigned int type, unsigned int line_no); 1534 extern void jbd2_journal_free_reserved(handle_t *handle); 1535 extern int jbd2_journal_extend(handle_t *handle, int nblocks, 1536 int revoke_records); 1537 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *); 1538 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *); 1539 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *); 1540 void jbd2_journal_set_triggers(struct buffer_head *, 1541 struct jbd2_buffer_trigger_type *type); 1542 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *); 1543 extern int jbd2_journal_forget (handle_t *, struct buffer_head *); 1544 int jbd2_journal_invalidate_folio(journal_t *, struct folio *, 1545 size_t offset, size_t length); 1546 bool jbd2_journal_try_to_free_buffers(journal_t *journal, struct folio *folio); 1547 extern int jbd2_journal_stop(handle_t *); 1548 extern int jbd2_journal_flush(journal_t *journal, unsigned int flags); 1549 extern void jbd2_journal_lock_updates (journal_t *); 1550 extern void jbd2_journal_unlock_updates (journal_t *); 1551 1552 void jbd2_journal_wait_updates(journal_t *); 1553 1554 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev, 1555 struct block_device *fs_dev, 1556 unsigned long long start, int len, int bsize); 1557 extern journal_t * jbd2_journal_init_inode (struct inode *); 1558 extern int jbd2_journal_update_format (journal_t *); 1559 extern int jbd2_journal_check_used_features 1560 (journal_t *, unsigned long, unsigned long, unsigned long); 1561 extern int jbd2_journal_check_available_features 1562 (journal_t *, unsigned long, unsigned long, unsigned long); 1563 extern int jbd2_journal_set_features 1564 (journal_t *, unsigned long, unsigned long, unsigned long); 1565 extern void jbd2_journal_clear_features 1566 (journal_t *, unsigned long, unsigned long, unsigned long); 1567 extern int jbd2_journal_load (journal_t *journal); 1568 extern int jbd2_journal_destroy (journal_t *); 1569 extern int jbd2_journal_recover (journal_t *journal); 1570 extern int jbd2_journal_wipe (journal_t *, int); 1571 extern int jbd2_journal_skip_recovery (journal_t *); 1572 extern void jbd2_journal_update_sb_errno(journal_t *); 1573 extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t, 1574 unsigned long, blk_opf_t); 1575 extern void jbd2_journal_abort (journal_t *, int); 1576 extern int jbd2_journal_errno (journal_t *); 1577 extern void jbd2_journal_ack_err (journal_t *); 1578 extern int jbd2_journal_clear_err (journal_t *); 1579 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *); 1580 extern int jbd2_journal_force_commit(journal_t *); 1581 extern int jbd2_journal_force_commit_nested(journal_t *); 1582 extern int jbd2_journal_inode_ranged_write(handle_t *handle, 1583 struct jbd2_inode *inode, loff_t start_byte, 1584 loff_t length); 1585 extern int jbd2_journal_inode_ranged_wait(handle_t *handle, 1586 struct jbd2_inode *inode, loff_t start_byte, 1587 loff_t length); 1588 extern int jbd2_journal_finish_inode_data_buffers( 1589 struct jbd2_inode *jinode); 1590 extern int jbd2_journal_begin_ordered_truncate(journal_t *journal, 1591 struct jbd2_inode *inode, loff_t new_size); 1592 extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode); 1593 extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode); 1594 1595 /* 1596 * journal_head management 1597 */ 1598 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh); 1599 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh); 1600 void jbd2_journal_put_journal_head(struct journal_head *jh); 1601 1602 /* 1603 * handle management 1604 */ 1605 extern struct kmem_cache *jbd2_handle_cache; 1606 1607 /* 1608 * This specialized allocator has to be a macro for its allocations to be 1609 * accounted separately (to have a separate alloc_tag). The typecast is 1610 * intentional to enforce typesafety. 1611 */ 1612 #define jbd2_alloc_handle(_gfp_flags) \ 1613 ((handle_t *)kmem_cache_zalloc(jbd2_handle_cache, _gfp_flags)) 1614 1615 static inline void jbd2_free_handle(handle_t *handle) 1616 { 1617 kmem_cache_free(jbd2_handle_cache, handle); 1618 } 1619 1620 /* 1621 * jbd2_inode management (optional, for those file systems that want to use 1622 * dynamically allocated jbd2_inode structures) 1623 */ 1624 extern struct kmem_cache *jbd2_inode_cache; 1625 1626 /* 1627 * This specialized allocator has to be a macro for its allocations to be 1628 * accounted separately (to have a separate alloc_tag). The typecast is 1629 * intentional to enforce typesafety. 1630 */ 1631 #define jbd2_alloc_inode(_gfp_flags) \ 1632 ((struct jbd2_inode *)kmem_cache_alloc(jbd2_inode_cache, _gfp_flags)) 1633 1634 static inline void jbd2_free_inode(struct jbd2_inode *jinode) 1635 { 1636 kmem_cache_free(jbd2_inode_cache, jinode); 1637 } 1638 1639 /* Primary revoke support */ 1640 #define JOURNAL_REVOKE_DEFAULT_HASH 256 1641 extern int jbd2_journal_init_revoke(journal_t *, int); 1642 extern void jbd2_journal_destroy_revoke_record_cache(void); 1643 extern void jbd2_journal_destroy_revoke_table_cache(void); 1644 extern int __init jbd2_journal_init_revoke_record_cache(void); 1645 extern int __init jbd2_journal_init_revoke_table_cache(void); 1646 struct jbd2_revoke_table_s *jbd2_journal_init_revoke_table(int hash_size); 1647 void jbd2_journal_destroy_revoke_table(struct jbd2_revoke_table_s *table); 1648 1649 extern void jbd2_journal_destroy_revoke(journal_t *); 1650 extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *); 1651 extern void jbd2_journal_cancel_revoke(handle_t *, struct journal_head *); 1652 extern void jbd2_journal_write_revoke_records(transaction_t *transaction, 1653 struct list_head *log_bufs); 1654 1655 /* Recovery revoke support */ 1656 extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t); 1657 extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t); 1658 extern void jbd2_journal_clear_revoke(journal_t *); 1659 extern void jbd2_journal_switch_revoke_table(journal_t *journal); 1660 extern void jbd2_clear_buffer_revoked_flags(journal_t *journal); 1661 1662 /* 1663 * The log thread user interface: 1664 * 1665 * Request space in the current transaction, and force transaction commit 1666 * transitions on demand. 1667 */ 1668 1669 int jbd2_log_start_commit(journal_t *journal, tid_t tid); 1670 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid); 1671 int jbd2_log_wait_commit(journal_t *journal, tid_t tid); 1672 int jbd2_transaction_committed(journal_t *journal, tid_t tid); 1673 int jbd2_complete_transaction(journal_t *journal, tid_t tid); 1674 int jbd2_log_do_checkpoint(journal_t *journal); 1675 int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid); 1676 1677 void __jbd2_log_wait_for_space(journal_t *journal); 1678 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *); 1679 extern int jbd2_cleanup_journal_tail(journal_t *); 1680 1681 /* Fast commit related APIs */ 1682 int jbd2_fc_begin_commit(journal_t *journal, tid_t tid); 1683 int jbd2_fc_end_commit(journal_t *journal); 1684 int jbd2_fc_end_commit_fallback(journal_t *journal); 1685 int jbd2_fc_get_buf(journal_t *journal, struct buffer_head **bh_out); 1686 int jbd2_submit_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1687 int jbd2_wait_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1688 int jbd2_fc_wait_bufs(journal_t *journal, int num_blks); 1689 void jbd2_fc_release_bufs(journal_t *journal); 1690 1691 /* 1692 * is_journal_abort 1693 * 1694 * Simple test wrapper function to test the JBD2_ABORT state flag. This 1695 * bit, when set, indicates that we have had a fatal error somewhere, 1696 * either inside the journaling layer or indicated to us by the client 1697 * (eg. ext3), and that we and should not commit any further 1698 * transactions. 1699 */ 1700 1701 static inline int is_journal_aborted(journal_t *journal) 1702 { 1703 return journal->j_flags & JBD2_ABORT; 1704 } 1705 1706 static inline int is_handle_aborted(handle_t *handle) 1707 { 1708 if (handle->h_aborted || !handle->h_transaction) 1709 return 1; 1710 return is_journal_aborted(handle->h_transaction->t_journal); 1711 } 1712 1713 static inline void jbd2_journal_abort_handle(handle_t *handle) 1714 { 1715 handle->h_aborted = 1; 1716 } 1717 1718 static inline void jbd2_init_fs_dev_write_error(journal_t *journal) 1719 { 1720 struct address_space *mapping = journal->j_fs_dev->bd_mapping; 1721 1722 /* 1723 * Save the original wb_err value of client fs's bdev mapping which 1724 * could be used to detect the client fs's metadata async write error. 1725 */ 1726 errseq_check_and_advance(&mapping->wb_err, &journal->j_fs_dev_wb_err); 1727 } 1728 1729 static inline int jbd2_check_fs_dev_write_error(journal_t *journal) 1730 { 1731 struct address_space *mapping = journal->j_fs_dev->bd_mapping; 1732 1733 return errseq_check(&mapping->wb_err, 1734 READ_ONCE(journal->j_fs_dev_wb_err)); 1735 } 1736 1737 #endif /* __KERNEL__ */ 1738 1739 /* Comparison functions for transaction IDs: perform comparisons using 1740 * modulo arithmetic so that they work over sequence number wraps. */ 1741 1742 static inline int tid_gt(tid_t x, tid_t y) 1743 { 1744 int difference = (x - y); 1745 return (difference > 0); 1746 } 1747 1748 static inline int tid_geq(tid_t x, tid_t y) 1749 { 1750 int difference = (x - y); 1751 return (difference >= 0); 1752 } 1753 1754 extern int jbd2_journal_blocks_per_folio(struct inode *inode); 1755 extern size_t journal_tag_bytes(journal_t *journal); 1756 1757 static inline int jbd2_journal_has_csum_v2or3(journal_t *journal) 1758 { 1759 return jbd2_has_feature_csum2(journal) || 1760 jbd2_has_feature_csum3(journal); 1761 } 1762 1763 static inline int jbd2_journal_get_num_fc_blks(journal_superblock_t *jsb) 1764 { 1765 int num_fc_blocks = be32_to_cpu(jsb->s_num_fc_blks); 1766 1767 return num_fc_blocks ? num_fc_blocks : JBD2_DEFAULT_FAST_COMMIT_BLOCKS; 1768 } 1769 1770 /* 1771 * Return number of free blocks in the log. Must be called under j_state_lock. 1772 */ 1773 static inline unsigned long jbd2_log_space_left(journal_t *journal) 1774 { 1775 /* Allow for rounding errors */ 1776 long free = journal->j_free - 32; 1777 1778 if (journal->j_committing_transaction) { 1779 free -= atomic_read(&journal-> 1780 j_committing_transaction->t_outstanding_credits); 1781 } 1782 return max_t(long, free, 0); 1783 } 1784 1785 /* 1786 * Definitions which augment the buffer_head layer 1787 */ 1788 1789 /* journaling buffer types */ 1790 #define BJ_None 0 /* Not journaled */ 1791 #define BJ_Metadata 1 /* Normal journaled metadata */ 1792 #define BJ_Forget 2 /* Buffer superseded by this transaction */ 1793 #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */ 1794 #define BJ_Reserved 4 /* Buffer is reserved for access by journal */ 1795 #define BJ_Types 5 1796 1797 static inline u32 jbd2_chksum(u32 crc, const void *address, unsigned int length) 1798 { 1799 return crc32c(crc, address, length); 1800 } 1801 1802 /* Return most recent uncommitted transaction */ 1803 static inline tid_t jbd2_get_latest_transaction(journal_t *journal) 1804 { 1805 tid_t tid; 1806 1807 read_lock(&journal->j_state_lock); 1808 tid = journal->j_commit_request; 1809 if (journal->j_running_transaction) 1810 tid = journal->j_running_transaction->t_tid; 1811 read_unlock(&journal->j_state_lock); 1812 return tid; 1813 } 1814 1815 static inline int jbd2_handle_buffer_credits(handle_t *handle) 1816 { 1817 journal_t *journal; 1818 1819 if (!handle->h_reserved) 1820 journal = handle->h_transaction->t_journal; 1821 else 1822 journal = handle->h_journal; 1823 1824 return handle->h_total_credits - 1825 DIV_ROUND_UP(handle->h_revoke_credits_requested, 1826 journal->j_revoke_records_per_block); 1827 } 1828 1829 #ifdef __KERNEL__ 1830 1831 #define buffer_trace_init(bh) do {} while (0) 1832 #define print_buffer_fields(bh) do {} while (0) 1833 #define print_buffer_trace(bh) do {} while (0) 1834 #define BUFFER_TRACE(bh, info) do {} while (0) 1835 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0) 1836 #define JBUFFER_TRACE(jh, info) do {} while (0) 1837 1838 #endif /* __KERNEL__ */ 1839 1840 #endif /* _LINUX_JBD2_H */ 1841