1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * linux/include/linux/jbd2.h 4 * 5 * Written by Stephen C. Tweedie <sct@redhat.com> 6 * 7 * Copyright 1998-2000 Red Hat, Inc --- All Rights Reserved 8 * 9 * Definitions for transaction data structures for the buffer cache 10 * filesystem journaling support. 11 */ 12 13 #ifndef _LINUX_JBD2_H 14 #define _LINUX_JBD2_H 15 16 /* Allow this file to be included directly into e2fsprogs */ 17 #ifndef __KERNEL__ 18 #include "jfs_compat.h" 19 #define JBD2_DEBUG 20 #else 21 22 #include <linux/types.h> 23 #include <linux/buffer_head.h> 24 #include <linux/journal-head.h> 25 #include <linux/stddef.h> 26 #include <linux/mutex.h> 27 #include <linux/timer.h> 28 #include <linux/slab.h> 29 #include <linux/bit_spinlock.h> 30 #include <linux/blkdev.h> 31 #include <crypto/hash.h> 32 #endif 33 34 #define journal_oom_retry 1 35 36 /* 37 * Define JBD2_PARANIOD_IOFAIL to cause a kernel BUG() if ext4 finds 38 * certain classes of error which can occur due to failed IOs. Under 39 * normal use we want ext4 to continue after such errors, because 40 * hardware _can_ fail, but for debugging purposes when running tests on 41 * known-good hardware we may want to trap these errors. 42 */ 43 #undef JBD2_PARANOID_IOFAIL 44 45 /* 46 * The default maximum commit age, in seconds. 47 */ 48 #define JBD2_DEFAULT_MAX_COMMIT_AGE 5 49 50 #ifdef CONFIG_JBD2_DEBUG 51 /* 52 * Define JBD2_EXPENSIVE_CHECKING to enable more expensive internal 53 * consistency checks. By default we don't do this unless 54 * CONFIG_JBD2_DEBUG is on. 55 */ 56 #define JBD2_EXPENSIVE_CHECKING 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 /* 0x0058 */ 269 __u32 s_padding[41]; 270 __be32 s_checksum; /* crc32c(superblock) */ 271 272 /* 0x0100 */ 273 __u8 s_users[16*48]; /* ids of all fs'es sharing the log */ 274 /* 0x0400 */ 275 } journal_superblock_t; 276 277 /* Use the jbd2_{has,set,clear}_feature_* helpers; these will be removed */ 278 #define JBD2_HAS_COMPAT_FEATURE(j,mask) \ 279 ((j)->j_format_version >= 2 && \ 280 ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask)))) 281 #define JBD2_HAS_RO_COMPAT_FEATURE(j,mask) \ 282 ((j)->j_format_version >= 2 && \ 283 ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask)))) 284 #define JBD2_HAS_INCOMPAT_FEATURE(j,mask) \ 285 ((j)->j_format_version >= 2 && \ 286 ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask)))) 287 288 #define JBD2_FEATURE_COMPAT_CHECKSUM 0x00000001 289 290 #define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001 291 #define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002 292 #define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT 0x00000004 293 #define JBD2_FEATURE_INCOMPAT_CSUM_V2 0x00000008 294 #define JBD2_FEATURE_INCOMPAT_CSUM_V3 0x00000010 295 #define JBD2_FEATURE_INCOMPAT_FAST_COMMIT 0x00000020 296 297 /* See "journal feature predicate functions" below */ 298 299 /* Features known to this kernel version: */ 300 #define JBD2_KNOWN_COMPAT_FEATURES JBD2_FEATURE_COMPAT_CHECKSUM 301 #define JBD2_KNOWN_ROCOMPAT_FEATURES 0 302 #define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \ 303 JBD2_FEATURE_INCOMPAT_64BIT | \ 304 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | \ 305 JBD2_FEATURE_INCOMPAT_CSUM_V2 | \ 306 JBD2_FEATURE_INCOMPAT_CSUM_V3 | \ 307 JBD2_FEATURE_INCOMPAT_FAST_COMMIT) 308 309 #ifdef __KERNEL__ 310 311 #include <linux/fs.h> 312 #include <linux/sched.h> 313 314 enum jbd_state_bits { 315 BH_JBD /* Has an attached ext3 journal_head */ 316 = BH_PrivateStart, 317 BH_JWrite, /* Being written to log (@@@ DEBUGGING) */ 318 BH_Freed, /* Has been freed (truncated) */ 319 BH_Revoked, /* Has been revoked from the log */ 320 BH_RevokeValid, /* Revoked flag is valid */ 321 BH_JBDDirty, /* Is dirty but journaled */ 322 BH_JournalHead, /* Pins bh->b_private and jh->b_bh */ 323 BH_Shadow, /* IO on shadow buffer is running */ 324 BH_Verified, /* Metadata block has been verified ok */ 325 BH_JBDPrivateStart, /* First bit available for private use by FS */ 326 }; 327 328 BUFFER_FNS(JBD, jbd) 329 BUFFER_FNS(JWrite, jwrite) 330 BUFFER_FNS(JBDDirty, jbddirty) 331 TAS_BUFFER_FNS(JBDDirty, jbddirty) 332 BUFFER_FNS(Revoked, revoked) 333 TAS_BUFFER_FNS(Revoked, revoked) 334 BUFFER_FNS(RevokeValid, revokevalid) 335 TAS_BUFFER_FNS(RevokeValid, revokevalid) 336 BUFFER_FNS(Freed, freed) 337 BUFFER_FNS(Shadow, shadow) 338 BUFFER_FNS(Verified, verified) 339 340 static inline struct buffer_head *jh2bh(struct journal_head *jh) 341 { 342 return jh->b_bh; 343 } 344 345 static inline struct journal_head *bh2jh(struct buffer_head *bh) 346 { 347 return bh->b_private; 348 } 349 350 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh) 351 { 352 bit_spin_lock(BH_JournalHead, &bh->b_state); 353 } 354 355 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh) 356 { 357 bit_spin_unlock(BH_JournalHead, &bh->b_state); 358 } 359 360 #define J_ASSERT(assert) BUG_ON(!(assert)) 361 362 #define J_ASSERT_BH(bh, expr) J_ASSERT(expr) 363 #define J_ASSERT_JH(jh, expr) J_ASSERT(expr) 364 365 #if defined(JBD2_PARANOID_IOFAIL) 366 #define J_EXPECT(expr, why...) J_ASSERT(expr) 367 #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr) 368 #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr) 369 #else 370 #define __journal_expect(expr, why...) \ 371 ({ \ 372 int val = (expr); \ 373 if (!val) { \ 374 printk(KERN_ERR \ 375 "JBD2 unexpected failure: %s: %s;\n", \ 376 __func__, #expr); \ 377 printk(KERN_ERR why "\n"); \ 378 } \ 379 val; \ 380 }) 381 #define J_EXPECT(expr, why...) __journal_expect(expr, ## why) 382 #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why) 383 #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why) 384 #endif 385 386 /* Flags in jbd_inode->i_flags */ 387 #define __JI_COMMIT_RUNNING 0 388 #define __JI_WRITE_DATA 1 389 #define __JI_WAIT_DATA 2 390 391 /* 392 * Commit of the inode data in progress. We use this flag to protect us from 393 * concurrent deletion of inode. We cannot use reference to inode for this 394 * since we cannot afford doing last iput() on behalf of kjournald 395 */ 396 #define JI_COMMIT_RUNNING (1 << __JI_COMMIT_RUNNING) 397 /* Write allocated dirty buffers in this inode before commit */ 398 #define JI_WRITE_DATA (1 << __JI_WRITE_DATA) 399 /* Wait for outstanding data writes for this inode before commit */ 400 #define JI_WAIT_DATA (1 << __JI_WAIT_DATA) 401 402 /** 403 * struct jbd2_inode - The jbd_inode type is the structure linking inodes in 404 * ordered mode present in a transaction so that we can sync them during commit. 405 */ 406 struct jbd2_inode { 407 /** 408 * @i_transaction: 409 * 410 * Which transaction does this inode belong to? Either the running 411 * transaction or the committing one. [j_list_lock] 412 */ 413 transaction_t *i_transaction; 414 415 /** 416 * @i_next_transaction: 417 * 418 * Pointer to the running transaction modifying inode's data in case 419 * there is already a committing transaction touching it. [j_list_lock] 420 */ 421 transaction_t *i_next_transaction; 422 423 /** 424 * @i_list: List of inodes in the i_transaction [j_list_lock] 425 */ 426 struct list_head i_list; 427 428 /** 429 * @i_vfs_inode: 430 * 431 * VFS inode this inode belongs to [constant for lifetime of structure] 432 */ 433 struct inode *i_vfs_inode; 434 435 /** 436 * @i_flags: Flags of inode [j_list_lock] 437 */ 438 unsigned long i_flags; 439 440 /** 441 * @i_dirty_start: 442 * 443 * Offset in bytes where the dirty range for this inode starts. 444 * [j_list_lock] 445 */ 446 loff_t i_dirty_start; 447 448 /** 449 * @i_dirty_end: 450 * 451 * Inclusive offset in bytes where the dirty range for this inode 452 * ends. [j_list_lock] 453 */ 454 loff_t i_dirty_end; 455 }; 456 457 struct jbd2_revoke_table_s; 458 459 /** 460 * struct jbd2_journal_handle - The jbd2_journal_handle type is the concrete 461 * type associated with handle_t. 462 * @h_transaction: Which compound transaction is this update a part of? 463 * @h_journal: Which journal handle belongs to - used iff h_reserved set. 464 * @h_rsv_handle: Handle reserved for finishing the logical operation. 465 * @h_total_credits: Number of remaining buffers we are allowed to add to 466 * journal. These are dirty buffers and revoke descriptor blocks. 467 * @h_revoke_credits: Number of remaining revoke records available for handle 468 * @h_ref: Reference count on this handle. 469 * @h_err: Field for caller's use to track errors through large fs operations. 470 * @h_sync: Flag for sync-on-close. 471 * @h_jdata: Flag to force data journaling. 472 * @h_reserved: Flag for handle for reserved credits. 473 * @h_aborted: Flag indicating fatal error on handle. 474 * @h_type: For handle statistics. 475 * @h_line_no: For handle statistics. 476 * @h_start_jiffies: Handle Start time. 477 * @h_requested_credits: Holds @h_total_credits after handle is started. 478 * @h_revoke_credits_requested: Holds @h_revoke_credits after handle is started. 479 * @saved_alloc_context: Saved context while transaction is open. 480 **/ 481 482 /* Docbook can't yet cope with the bit fields, but will leave the documentation 483 * in so it can be fixed later. 484 */ 485 486 struct jbd2_journal_handle 487 { 488 union { 489 transaction_t *h_transaction; 490 /* Which journal handle belongs to - used iff h_reserved set */ 491 journal_t *h_journal; 492 }; 493 494 handle_t *h_rsv_handle; 495 int h_total_credits; 496 int h_revoke_credits; 497 int h_revoke_credits_requested; 498 int h_ref; 499 int h_err; 500 501 /* Flags [no locking] */ 502 unsigned int h_sync: 1; 503 unsigned int h_jdata: 1; 504 unsigned int h_reserved: 1; 505 unsigned int h_aborted: 1; 506 unsigned int h_type: 8; 507 unsigned int h_line_no: 16; 508 509 unsigned long h_start_jiffies; 510 unsigned int h_requested_credits; 511 512 unsigned int saved_alloc_context; 513 }; 514 515 516 /* 517 * Some stats for checkpoint phase 518 */ 519 struct transaction_chp_stats_s { 520 unsigned long cs_chp_time; 521 __u32 cs_forced_to_close; 522 __u32 cs_written; 523 __u32 cs_dropped; 524 }; 525 526 /* The transaction_t type is the guts of the journaling mechanism. It 527 * tracks a compound transaction through its various states: 528 * 529 * RUNNING: accepting new updates 530 * LOCKED: Updates still running but we don't accept new ones 531 * RUNDOWN: Updates are tidying up but have finished requesting 532 * new buffers to modify (state not used for now) 533 * FLUSH: All updates complete, but we are still writing to disk 534 * COMMIT: All data on disk, writing commit record 535 * FINISHED: We still have to keep the transaction for checkpointing. 536 * 537 * The transaction keeps track of all of the buffers modified by a 538 * running transaction, and all of the buffers committed but not yet 539 * flushed to home for finished transactions. 540 * (Locking Documentation improved by LockDoc) 541 */ 542 543 /* 544 * Lock ranking: 545 * 546 * j_list_lock 547 * ->jbd_lock_bh_journal_head() (This is "innermost") 548 * 549 * j_state_lock 550 * ->b_state_lock 551 * 552 * b_state_lock 553 * ->j_list_lock 554 * 555 * j_state_lock 556 * ->j_list_lock (journal_unmap_buffer) 557 * 558 */ 559 560 struct transaction_s 561 { 562 /* Pointer to the journal for this transaction. [no locking] */ 563 journal_t *t_journal; 564 565 /* Sequence number for this transaction [no locking] */ 566 tid_t t_tid; 567 568 /* 569 * Transaction's current state 570 * [no locking - only kjournald2 alters this] 571 * [j_list_lock] guards transition of a transaction into T_FINISHED 572 * state and subsequent call of __jbd2_journal_drop_transaction() 573 * FIXME: needs barriers 574 * KLUDGE: [use j_state_lock] 575 */ 576 enum { 577 T_RUNNING, 578 T_LOCKED, 579 T_SWITCH, 580 T_FLUSH, 581 T_COMMIT, 582 T_COMMIT_DFLUSH, 583 T_COMMIT_JFLUSH, 584 T_COMMIT_CALLBACK, 585 T_FINISHED 586 } t_state; 587 588 /* 589 * Where in the log does this transaction's commit start? [no locking] 590 */ 591 unsigned long t_log_start; 592 593 /* 594 * Number of buffers on the t_buffers list [j_list_lock, no locks 595 * needed for jbd2 thread] 596 */ 597 int t_nr_buffers; 598 599 /* 600 * Doubly-linked circular list of all buffers reserved but not yet 601 * modified by this transaction [j_list_lock, no locks needed fo 602 * jbd2 thread] 603 */ 604 struct journal_head *t_reserved_list; 605 606 /* 607 * Doubly-linked circular list of all metadata buffers owned by this 608 * transaction [j_list_lock, no locks needed for jbd2 thread] 609 */ 610 struct journal_head *t_buffers; 611 612 /* 613 * Doubly-linked circular list of all forget buffers (superseded 614 * buffers which we can un-checkpoint once this transaction commits) 615 * [j_list_lock] 616 */ 617 struct journal_head *t_forget; 618 619 /* 620 * Doubly-linked circular list of all buffers still to be flushed before 621 * this transaction can be checkpointed. [j_list_lock] 622 */ 623 struct journal_head *t_checkpoint_list; 624 625 /* 626 * Doubly-linked circular list of all buffers submitted for IO while 627 * checkpointing. [j_list_lock] 628 */ 629 struct journal_head *t_checkpoint_io_list; 630 631 /* 632 * Doubly-linked circular list of metadata buffers being 633 * shadowed by log IO. The IO buffers on the iobuf list and 634 * the shadow buffers on this list match each other one for 635 * one at all times. [j_list_lock, no locks needed for jbd2 636 * thread] 637 */ 638 struct journal_head *t_shadow_list; 639 640 /* 641 * List of inodes associated with the transaction; e.g., ext4 uses 642 * this to track inodes in data=ordered and data=journal mode that 643 * need special handling on transaction commit; also used by ocfs2. 644 * [j_list_lock] 645 */ 646 struct list_head t_inode_list; 647 648 /* 649 * Protects info related to handles 650 */ 651 spinlock_t t_handle_lock; 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 * For use by the filesystem to store fs-specific data 726 * structures associated with the transaction 727 */ 728 struct list_head t_private_list; 729 }; 730 731 struct transaction_run_stats_s { 732 unsigned long rs_wait; 733 unsigned long rs_request_delay; 734 unsigned long rs_running; 735 unsigned long rs_locked; 736 unsigned long rs_flushing; 737 unsigned long rs_logging; 738 739 __u32 rs_handle_count; 740 __u32 rs_blocks; 741 __u32 rs_blocks_logged; 742 }; 743 744 struct transaction_stats_s { 745 unsigned long ts_tid; 746 unsigned long ts_requested; 747 struct transaction_run_stats_s run; 748 }; 749 750 static inline unsigned long 751 jbd2_time_diff(unsigned long start, unsigned long end) 752 { 753 if (end >= start) 754 return end - start; 755 756 return end + (MAX_JIFFY_OFFSET - start); 757 } 758 759 #define JBD2_NR_BATCH 64 760 761 enum passtype {PASS_SCAN, PASS_REVOKE, PASS_REPLAY}; 762 763 #define JBD2_FC_REPLAY_STOP 0 764 #define JBD2_FC_REPLAY_CONTINUE 1 765 766 /** 767 * struct journal_s - The journal_s type is the concrete type associated with 768 * journal_t. 769 */ 770 struct journal_s 771 { 772 /** 773 * @j_flags: General journaling state flags [j_state_lock, 774 * no lock for quick racy checks] 775 */ 776 unsigned long j_flags; 777 778 /** 779 * @j_atomic_flags: Atomic journaling state flags. 780 */ 781 unsigned long j_atomic_flags; 782 783 /** 784 * @j_errno: 785 * 786 * Is there an outstanding uncleared error on the journal (from a prior 787 * abort)? [j_state_lock] 788 */ 789 int j_errno; 790 791 /** 792 * @j_abort_mutex: Lock the whole aborting procedure. 793 */ 794 struct mutex j_abort_mutex; 795 796 /** 797 * @j_sb_buffer: The first part of the superblock buffer. 798 */ 799 struct buffer_head *j_sb_buffer; 800 801 /** 802 * @j_superblock: The second part of the superblock buffer. 803 */ 804 journal_superblock_t *j_superblock; 805 806 /** 807 * @j_format_version: Version of the superblock format. 808 */ 809 int j_format_version; 810 811 /** 812 * @j_state_lock: Protect the various scalars in the journal. 813 */ 814 rwlock_t j_state_lock; 815 816 /** 817 * @j_barrier_count: 818 * 819 * Number of processes waiting to create a barrier lock [j_state_lock, 820 * no lock for quick racy checks] 821 */ 822 int j_barrier_count; 823 824 /** 825 * @j_barrier: The barrier lock itself. 826 */ 827 struct mutex j_barrier; 828 829 /** 830 * @j_running_transaction: 831 * 832 * Transactions: The current running transaction... 833 * [j_state_lock, no lock for quick racy checks] [caller holding 834 * open handle] 835 */ 836 transaction_t *j_running_transaction; 837 838 /** 839 * @j_committing_transaction: 840 * 841 * the transaction we are pushing to disk 842 * [j_state_lock] [caller holding open handle] 843 */ 844 transaction_t *j_committing_transaction; 845 846 /** 847 * @j_checkpoint_transactions: 848 * 849 * ... and a linked circular list of all transactions waiting for 850 * checkpointing. [j_list_lock] 851 */ 852 transaction_t *j_checkpoint_transactions; 853 854 /** 855 * @j_wait_transaction_locked: 856 * 857 * Wait queue for waiting for a locked transaction to start committing, 858 * or for a barrier lock to be released. 859 */ 860 wait_queue_head_t j_wait_transaction_locked; 861 862 /** 863 * @j_wait_done_commit: Wait queue for waiting for commit to complete. 864 */ 865 wait_queue_head_t j_wait_done_commit; 866 867 /** 868 * @j_wait_commit: Wait queue to trigger commit. 869 */ 870 wait_queue_head_t j_wait_commit; 871 872 /** 873 * @j_wait_updates: Wait queue to wait for updates to complete. 874 */ 875 wait_queue_head_t j_wait_updates; 876 877 /** 878 * @j_wait_reserved: 879 * 880 * Wait queue to wait for reserved buffer credits to drop. 881 */ 882 wait_queue_head_t j_wait_reserved; 883 884 /** 885 * @j_fc_wait: 886 * 887 * Wait queue to wait for completion of async fast commits. 888 */ 889 wait_queue_head_t j_fc_wait; 890 891 /** 892 * @j_checkpoint_mutex: 893 * 894 * Semaphore for locking against concurrent checkpoints. 895 */ 896 struct mutex j_checkpoint_mutex; 897 898 /** 899 * @j_chkpt_bhs: 900 * 901 * List of buffer heads used by the checkpoint routine. This 902 * was moved from jbd2_log_do_checkpoint() to reduce stack 903 * usage. Access to this array is controlled by the 904 * @j_checkpoint_mutex. [j_checkpoint_mutex] 905 */ 906 struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH]; 907 908 /** 909 * @j_shrinker: 910 * 911 * Journal head shrinker, reclaim buffer's journal head which 912 * has been written back. 913 */ 914 struct shrinker j_shrinker; 915 916 /** 917 * @j_checkpoint_jh_count: 918 * 919 * Number of journal buffers on the checkpoint list. [j_list_lock] 920 */ 921 struct percpu_counter j_checkpoint_jh_count; 922 923 /** 924 * @j_shrink_transaction: 925 * 926 * Record next transaction will shrink on the checkpoint list. 927 * [j_list_lock] 928 */ 929 transaction_t *j_shrink_transaction; 930 931 /** 932 * @j_head: 933 * 934 * Journal head: identifies the first unused block in the journal. 935 * [j_state_lock] 936 */ 937 unsigned long j_head; 938 939 /** 940 * @j_tail: 941 * 942 * Journal tail: identifies the oldest still-used block in the journal. 943 * [j_state_lock] 944 */ 945 unsigned long j_tail; 946 947 /** 948 * @j_free: 949 * 950 * Journal free: how many free blocks are there in the journal? 951 * [j_state_lock] 952 */ 953 unsigned long j_free; 954 955 /** 956 * @j_first: 957 * 958 * The block number of the first usable block in the journal 959 * [j_state_lock]. 960 */ 961 unsigned long j_first; 962 963 /** 964 * @j_last: 965 * 966 * The block number one beyond the last usable block in the journal 967 * [j_state_lock]. 968 */ 969 unsigned long j_last; 970 971 /** 972 * @j_fc_first: 973 * 974 * The block number of the first fast commit block in the journal 975 * [j_state_lock]. 976 */ 977 unsigned long j_fc_first; 978 979 /** 980 * @j_fc_off: 981 * 982 * Number of fast commit blocks currently allocated. Accessed only 983 * during fast commit. Currently only process can do fast commit, so 984 * this field is not protected by any lock. 985 */ 986 unsigned long j_fc_off; 987 988 /** 989 * @j_fc_last: 990 * 991 * The block number one beyond the last fast commit block in the journal 992 * [j_state_lock]. 993 */ 994 unsigned long j_fc_last; 995 996 /** 997 * @j_dev: Device where we store the journal. 998 */ 999 struct block_device *j_dev; 1000 1001 /** 1002 * @j_blocksize: Block size for the location where we store the journal. 1003 */ 1004 int j_blocksize; 1005 1006 /** 1007 * @j_blk_offset: 1008 * 1009 * Starting block offset into the device where we store the journal. 1010 */ 1011 unsigned long long j_blk_offset; 1012 1013 /** 1014 * @j_devname: Journal device name. 1015 */ 1016 char j_devname[BDEVNAME_SIZE+24]; 1017 1018 /** 1019 * @j_fs_dev: 1020 * 1021 * Device which holds the client fs. For internal journal this will be 1022 * equal to j_dev. 1023 */ 1024 struct block_device *j_fs_dev; 1025 1026 /** 1027 * @j_total_len: Total maximum capacity of the journal region on disk. 1028 */ 1029 unsigned int j_total_len; 1030 1031 /** 1032 * @j_reserved_credits: 1033 * 1034 * Number of buffers reserved from the running transaction. 1035 */ 1036 atomic_t j_reserved_credits; 1037 1038 /** 1039 * @j_list_lock: Protects the buffer lists and internal buffer state. 1040 */ 1041 spinlock_t j_list_lock; 1042 1043 /** 1044 * @j_inode: 1045 * 1046 * Optional inode where we store the journal. If present, all 1047 * journal block numbers are mapped into this inode via bmap(). 1048 */ 1049 struct inode *j_inode; 1050 1051 /** 1052 * @j_tail_sequence: 1053 * 1054 * Sequence number of the oldest transaction in the log [j_state_lock] 1055 */ 1056 tid_t j_tail_sequence; 1057 1058 /** 1059 * @j_transaction_sequence: 1060 * 1061 * Sequence number of the next transaction to grant [j_state_lock] 1062 */ 1063 tid_t j_transaction_sequence; 1064 1065 /** 1066 * @j_commit_sequence: 1067 * 1068 * Sequence number of the most recently committed transaction 1069 * [j_state_lock, no lock for quick racy checks] 1070 */ 1071 tid_t j_commit_sequence; 1072 1073 /** 1074 * @j_commit_request: 1075 * 1076 * Sequence number of the most recent transaction wanting commit 1077 * [j_state_lock, no lock for quick racy checks] 1078 */ 1079 tid_t j_commit_request; 1080 1081 /** 1082 * @j_uuid: 1083 * 1084 * Journal uuid: identifies the object (filesystem, LVM volume etc) 1085 * backed by this journal. This will eventually be replaced by an array 1086 * of uuids, allowing us to index multiple devices within a single 1087 * journal and to perform atomic updates across them. 1088 */ 1089 __u8 j_uuid[16]; 1090 1091 /** 1092 * @j_task: Pointer to the current commit thread for this journal. 1093 */ 1094 struct task_struct *j_task; 1095 1096 /** 1097 * @j_max_transaction_buffers: 1098 * 1099 * Maximum number of metadata buffers to allow in a single compound 1100 * commit transaction. 1101 */ 1102 int j_max_transaction_buffers; 1103 1104 /** 1105 * @j_revoke_records_per_block: 1106 * 1107 * Number of revoke records that fit in one descriptor block. 1108 */ 1109 int j_revoke_records_per_block; 1110 1111 /** 1112 * @j_commit_interval: 1113 * 1114 * What is the maximum transaction lifetime before we begin a commit? 1115 */ 1116 unsigned long j_commit_interval; 1117 1118 /** 1119 * @j_commit_timer: The timer used to wakeup the commit thread. 1120 */ 1121 struct timer_list j_commit_timer; 1122 1123 /** 1124 * @j_revoke_lock: Protect the revoke table. 1125 */ 1126 spinlock_t j_revoke_lock; 1127 1128 /** 1129 * @j_revoke: 1130 * 1131 * The revoke table - maintains the list of revoked blocks in the 1132 * current transaction. 1133 */ 1134 struct jbd2_revoke_table_s *j_revoke; 1135 1136 /** 1137 * @j_revoke_table: Alternate revoke tables for j_revoke. 1138 */ 1139 struct jbd2_revoke_table_s *j_revoke_table[2]; 1140 1141 /** 1142 * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction. 1143 */ 1144 struct buffer_head **j_wbuf; 1145 1146 /** 1147 * @j_fc_wbuf: Array of fast commit bhs for fast commit. Accessed only 1148 * during a fast commit. Currently only process can do fast commit, so 1149 * this field is not protected by any lock. 1150 */ 1151 struct buffer_head **j_fc_wbuf; 1152 1153 /** 1154 * @j_wbufsize: 1155 * 1156 * Size of @j_wbuf array. 1157 */ 1158 int j_wbufsize; 1159 1160 /** 1161 * @j_fc_wbufsize: 1162 * 1163 * Size of @j_fc_wbuf array. 1164 */ 1165 int j_fc_wbufsize; 1166 1167 /** 1168 * @j_last_sync_writer: 1169 * 1170 * The pid of the last person to run a synchronous operation 1171 * through the journal. 1172 */ 1173 pid_t j_last_sync_writer; 1174 1175 /** 1176 * @j_average_commit_time: 1177 * 1178 * The average amount of time in nanoseconds it takes to commit a 1179 * transaction to disk. [j_state_lock] 1180 */ 1181 u64 j_average_commit_time; 1182 1183 /** 1184 * @j_min_batch_time: 1185 * 1186 * Minimum time that we should wait for additional filesystem operations 1187 * to get batched into a synchronous handle in microseconds. 1188 */ 1189 u32 j_min_batch_time; 1190 1191 /** 1192 * @j_max_batch_time: 1193 * 1194 * Maximum time that we should wait for additional filesystem operations 1195 * to get batched into a synchronous handle in microseconds. 1196 */ 1197 u32 j_max_batch_time; 1198 1199 /** 1200 * @j_commit_callback: 1201 * 1202 * This function is called when a transaction is closed. 1203 */ 1204 void (*j_commit_callback)(journal_t *, 1205 transaction_t *); 1206 1207 /** 1208 * @j_submit_inode_data_buffers: 1209 * 1210 * This function is called for all inodes associated with the 1211 * committing transaction marked with JI_WRITE_DATA flag 1212 * before we start to write out the transaction to the journal. 1213 */ 1214 int (*j_submit_inode_data_buffers) 1215 (struct jbd2_inode *); 1216 1217 /** 1218 * @j_finish_inode_data_buffers: 1219 * 1220 * This function is called for all inodes associated with the 1221 * committing transaction marked with JI_WAIT_DATA flag 1222 * after we have written the transaction to the journal 1223 * but before we write out the commit block. 1224 */ 1225 int (*j_finish_inode_data_buffers) 1226 (struct jbd2_inode *); 1227 1228 /* 1229 * Journal statistics 1230 */ 1231 1232 /** 1233 * @j_history_lock: Protect the transactions statistics history. 1234 */ 1235 spinlock_t j_history_lock; 1236 1237 /** 1238 * @j_proc_entry: procfs entry for the jbd statistics directory. 1239 */ 1240 struct proc_dir_entry *j_proc_entry; 1241 1242 /** 1243 * @j_stats: Overall statistics. 1244 */ 1245 struct transaction_stats_s j_stats; 1246 1247 /** 1248 * @j_failed_commit: Failed journal commit ID. 1249 */ 1250 unsigned int j_failed_commit; 1251 1252 /** 1253 * @j_private: 1254 * 1255 * An opaque pointer to fs-private information. ext3 puts its 1256 * superblock pointer here. 1257 */ 1258 void *j_private; 1259 1260 /** 1261 * @j_chksum_driver: 1262 * 1263 * Reference to checksum algorithm driver via cryptoapi. 1264 */ 1265 struct crypto_shash *j_chksum_driver; 1266 1267 /** 1268 * @j_csum_seed: 1269 * 1270 * Precomputed journal UUID checksum for seeding other checksums. 1271 */ 1272 __u32 j_csum_seed; 1273 1274 #ifdef CONFIG_DEBUG_LOCK_ALLOC 1275 /** 1276 * @j_trans_commit_map: 1277 * 1278 * Lockdep entity to track transaction commit dependencies. Handles 1279 * hold this "lock" for read, when we wait for commit, we acquire the 1280 * "lock" for writing. This matches the properties of jbd2 journalling 1281 * where the running transaction has to wait for all handles to be 1282 * dropped to commit that transaction and also acquiring a handle may 1283 * require transaction commit to finish. 1284 */ 1285 struct lockdep_map j_trans_commit_map; 1286 #endif 1287 1288 /** 1289 * @j_fc_cleanup_callback: 1290 * 1291 * Clean-up after fast commit or full commit. JBD2 calls this function 1292 * after every commit operation. 1293 */ 1294 void (*j_fc_cleanup_callback)(struct journal_s *journal, int full, tid_t tid); 1295 1296 /** 1297 * @j_fc_replay_callback: 1298 * 1299 * File-system specific function that performs replay of a fast 1300 * commit. JBD2 calls this function for each fast commit block found in 1301 * the journal. This function should return JBD2_FC_REPLAY_CONTINUE 1302 * to indicate that the block was processed correctly and more fast 1303 * commit replay should continue. Return value of JBD2_FC_REPLAY_STOP 1304 * indicates the end of replay (no more blocks remaining). A negative 1305 * return value indicates error. 1306 */ 1307 int (*j_fc_replay_callback)(struct journal_s *journal, 1308 struct buffer_head *bh, 1309 enum passtype pass, int off, 1310 tid_t expected_commit_id); 1311 1312 /** 1313 * @j_bmap: 1314 * 1315 * Bmap function that should be used instead of the generic 1316 * VFS bmap function. 1317 */ 1318 int (*j_bmap)(struct journal_s *journal, sector_t *block); 1319 }; 1320 1321 #define jbd2_might_wait_for_commit(j) \ 1322 do { \ 1323 rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \ 1324 rwsem_release(&j->j_trans_commit_map, _THIS_IP_); \ 1325 } while (0) 1326 1327 /* journal feature predicate functions */ 1328 #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \ 1329 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1330 { \ 1331 return ((j)->j_format_version >= 2 && \ 1332 ((j)->j_superblock->s_feature_compat & \ 1333 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \ 1334 } \ 1335 static inline void jbd2_set_feature_##name(journal_t *j) \ 1336 { \ 1337 (j)->j_superblock->s_feature_compat |= \ 1338 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1339 } \ 1340 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1341 { \ 1342 (j)->j_superblock->s_feature_compat &= \ 1343 ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1344 } 1345 1346 #define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \ 1347 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1348 { \ 1349 return ((j)->j_format_version >= 2 && \ 1350 ((j)->j_superblock->s_feature_ro_compat & \ 1351 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \ 1352 } \ 1353 static inline void jbd2_set_feature_##name(journal_t *j) \ 1354 { \ 1355 (j)->j_superblock->s_feature_ro_compat |= \ 1356 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1357 } \ 1358 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1359 { \ 1360 (j)->j_superblock->s_feature_ro_compat &= \ 1361 ~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1362 } 1363 1364 #define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \ 1365 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1366 { \ 1367 return ((j)->j_format_version >= 2 && \ 1368 ((j)->j_superblock->s_feature_incompat & \ 1369 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \ 1370 } \ 1371 static inline void jbd2_set_feature_##name(journal_t *j) \ 1372 { \ 1373 (j)->j_superblock->s_feature_incompat |= \ 1374 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1375 } \ 1376 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1377 { \ 1378 (j)->j_superblock->s_feature_incompat &= \ 1379 ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1380 } 1381 1382 JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM) 1383 1384 JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE) 1385 JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT) 1386 JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT) 1387 JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2) 1388 JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3) 1389 JBD2_FEATURE_INCOMPAT_FUNCS(fast_commit, FAST_COMMIT) 1390 1391 /* 1392 * Journal flag definitions 1393 */ 1394 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */ 1395 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */ 1396 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */ 1397 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */ 1398 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */ 1399 #define JBD2_BARRIER 0x020 /* Use IDE barriers */ 1400 #define JBD2_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file 1401 * data write error in ordered 1402 * mode */ 1403 #define JBD2_FAST_COMMIT_ONGOING 0x100 /* Fast commit is ongoing */ 1404 #define JBD2_FULL_COMMIT_ONGOING 0x200 /* Full commit is ongoing */ 1405 #define JBD2_JOURNAL_FLUSH_DISCARD 0x0001 1406 #define JBD2_JOURNAL_FLUSH_ZEROOUT 0x0002 1407 #define JBD2_JOURNAL_FLUSH_VALID (JBD2_JOURNAL_FLUSH_DISCARD | \ 1408 JBD2_JOURNAL_FLUSH_ZEROOUT) 1409 1410 /* 1411 * Journal atomic flag definitions 1412 */ 1413 #define JBD2_CHECKPOINT_IO_ERROR 0x001 /* Detect io error while writing 1414 * buffer back to disk */ 1415 1416 /* 1417 * Function declarations for the journaling transaction and buffer 1418 * management 1419 */ 1420 1421 /* Filing buffers */ 1422 extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *); 1423 extern bool __jbd2_journal_refile_buffer(struct journal_head *); 1424 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *); 1425 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1426 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1427 static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh) 1428 { 1429 list_add_tail(&bh->b_assoc_buffers, head); 1430 } 1431 static inline void jbd2_unfile_log_bh(struct buffer_head *bh) 1432 { 1433 list_del_init(&bh->b_assoc_buffers); 1434 } 1435 1436 /* Log buffer allocation */ 1437 struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int); 1438 void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *); 1439 int jbd2_journal_next_log_block(journal_t *, unsigned long long *); 1440 int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, 1441 unsigned long *block); 1442 int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1443 void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1444 1445 /* Commit management */ 1446 extern void jbd2_journal_commit_transaction(journal_t *); 1447 1448 /* Checkpoint list management */ 1449 void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy); 1450 unsigned long jbd2_journal_shrink_checkpoint_list(journal_t *journal, unsigned long *nr_to_scan); 1451 int __jbd2_journal_remove_checkpoint(struct journal_head *); 1452 void jbd2_journal_destroy_checkpoint(journal_t *journal); 1453 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *); 1454 1455 1456 /* 1457 * Triggers 1458 */ 1459 1460 struct jbd2_buffer_trigger_type { 1461 /* 1462 * Fired a the moment data to write to the journal are known to be 1463 * stable - so either at the moment b_frozen_data is created or just 1464 * before a buffer is written to the journal. mapped_data is a mapped 1465 * buffer that is the frozen data for commit. 1466 */ 1467 void (*t_frozen)(struct jbd2_buffer_trigger_type *type, 1468 struct buffer_head *bh, void *mapped_data, 1469 size_t size); 1470 1471 /* 1472 * Fired during journal abort for dirty buffers that will not be 1473 * committed. 1474 */ 1475 void (*t_abort)(struct jbd2_buffer_trigger_type *type, 1476 struct buffer_head *bh); 1477 }; 1478 1479 extern void jbd2_buffer_frozen_trigger(struct journal_head *jh, 1480 void *mapped_data, 1481 struct jbd2_buffer_trigger_type *triggers); 1482 extern void jbd2_buffer_abort_trigger(struct journal_head *jh, 1483 struct jbd2_buffer_trigger_type *triggers); 1484 1485 /* Buffer IO */ 1486 extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction, 1487 struct journal_head *jh_in, 1488 struct buffer_head **bh_out, 1489 sector_t blocknr); 1490 1491 /* Transaction cache support */ 1492 extern void jbd2_journal_destroy_transaction_cache(void); 1493 extern int __init jbd2_journal_init_transaction_cache(void); 1494 extern void jbd2_journal_free_transaction(transaction_t *); 1495 1496 /* 1497 * Journal locking. 1498 * 1499 * We need to lock the journal during transaction state changes so that nobody 1500 * ever tries to take a handle on the running transaction while we are in the 1501 * middle of moving it to the commit phase. j_state_lock does this. 1502 * 1503 * Note that the locking is completely interrupt unsafe. We never touch 1504 * journal structures from interrupts. 1505 */ 1506 1507 static inline handle_t *journal_current_handle(void) 1508 { 1509 return current->journal_info; 1510 } 1511 1512 /* The journaling code user interface: 1513 * 1514 * Create and destroy handles 1515 * Register buffer modifications against the current transaction. 1516 */ 1517 1518 extern handle_t *jbd2_journal_start(journal_t *, int nblocks); 1519 extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks, 1520 int revoke_records, gfp_t gfp_mask, 1521 unsigned int type, unsigned int line_no); 1522 extern int jbd2_journal_restart(handle_t *, int nblocks); 1523 extern int jbd2__journal_restart(handle_t *, int nblocks, 1524 int revoke_records, gfp_t gfp_mask); 1525 extern int jbd2_journal_start_reserved(handle_t *handle, 1526 unsigned int type, unsigned int line_no); 1527 extern void jbd2_journal_free_reserved(handle_t *handle); 1528 extern int jbd2_journal_extend(handle_t *handle, int nblocks, 1529 int revoke_records); 1530 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *); 1531 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *); 1532 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *); 1533 void jbd2_journal_set_triggers(struct buffer_head *, 1534 struct jbd2_buffer_trigger_type *type); 1535 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *); 1536 extern int jbd2_journal_forget (handle_t *, struct buffer_head *); 1537 int jbd2_journal_invalidate_folio(journal_t *, struct folio *, 1538 size_t offset, size_t length); 1539 bool jbd2_journal_try_to_free_buffers(journal_t *journal, struct folio *folio); 1540 extern int jbd2_journal_stop(handle_t *); 1541 extern int jbd2_journal_flush(journal_t *journal, unsigned int flags); 1542 extern void jbd2_journal_lock_updates (journal_t *); 1543 extern void jbd2_journal_unlock_updates (journal_t *); 1544 1545 void jbd2_journal_wait_updates(journal_t *); 1546 1547 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev, 1548 struct block_device *fs_dev, 1549 unsigned long long start, int len, int bsize); 1550 extern journal_t * jbd2_journal_init_inode (struct inode *); 1551 extern int jbd2_journal_update_format (journal_t *); 1552 extern int jbd2_journal_check_used_features 1553 (journal_t *, unsigned long, unsigned long, unsigned long); 1554 extern int jbd2_journal_check_available_features 1555 (journal_t *, unsigned long, unsigned long, unsigned long); 1556 extern int jbd2_journal_set_features 1557 (journal_t *, unsigned long, unsigned long, unsigned long); 1558 extern void jbd2_journal_clear_features 1559 (journal_t *, unsigned long, unsigned long, unsigned long); 1560 extern int jbd2_journal_load (journal_t *journal); 1561 extern int jbd2_journal_destroy (journal_t *); 1562 extern int jbd2_journal_recover (journal_t *journal); 1563 extern int jbd2_journal_wipe (journal_t *, int); 1564 extern int jbd2_journal_skip_recovery (journal_t *); 1565 extern void jbd2_journal_update_sb_errno(journal_t *); 1566 extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t, 1567 unsigned long, blk_opf_t); 1568 extern void jbd2_journal_abort (journal_t *, int); 1569 extern int jbd2_journal_errno (journal_t *); 1570 extern void jbd2_journal_ack_err (journal_t *); 1571 extern int jbd2_journal_clear_err (journal_t *); 1572 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *); 1573 extern int jbd2_journal_force_commit(journal_t *); 1574 extern int jbd2_journal_force_commit_nested(journal_t *); 1575 extern int jbd2_journal_inode_ranged_write(handle_t *handle, 1576 struct jbd2_inode *inode, loff_t start_byte, 1577 loff_t length); 1578 extern int jbd2_journal_inode_ranged_wait(handle_t *handle, 1579 struct jbd2_inode *inode, loff_t start_byte, 1580 loff_t length); 1581 extern int jbd2_journal_finish_inode_data_buffers( 1582 struct jbd2_inode *jinode); 1583 extern int jbd2_journal_begin_ordered_truncate(journal_t *journal, 1584 struct jbd2_inode *inode, loff_t new_size); 1585 extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode); 1586 extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode); 1587 1588 /* 1589 * journal_head management 1590 */ 1591 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh); 1592 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh); 1593 void jbd2_journal_put_journal_head(struct journal_head *jh); 1594 1595 /* 1596 * handle management 1597 */ 1598 extern struct kmem_cache *jbd2_handle_cache; 1599 1600 static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags) 1601 { 1602 return kmem_cache_zalloc(jbd2_handle_cache, gfp_flags); 1603 } 1604 1605 static inline void jbd2_free_handle(handle_t *handle) 1606 { 1607 kmem_cache_free(jbd2_handle_cache, handle); 1608 } 1609 1610 /* 1611 * jbd2_inode management (optional, for those file systems that want to use 1612 * dynamically allocated jbd2_inode structures) 1613 */ 1614 extern struct kmem_cache *jbd2_inode_cache; 1615 1616 static inline struct jbd2_inode *jbd2_alloc_inode(gfp_t gfp_flags) 1617 { 1618 return kmem_cache_alloc(jbd2_inode_cache, gfp_flags); 1619 } 1620 1621 static inline void jbd2_free_inode(struct jbd2_inode *jinode) 1622 { 1623 kmem_cache_free(jbd2_inode_cache, jinode); 1624 } 1625 1626 /* Primary revoke support */ 1627 #define JOURNAL_REVOKE_DEFAULT_HASH 256 1628 extern int jbd2_journal_init_revoke(journal_t *, int); 1629 extern void jbd2_journal_destroy_revoke_record_cache(void); 1630 extern void jbd2_journal_destroy_revoke_table_cache(void); 1631 extern int __init jbd2_journal_init_revoke_record_cache(void); 1632 extern int __init jbd2_journal_init_revoke_table_cache(void); 1633 1634 extern void jbd2_journal_destroy_revoke(journal_t *); 1635 extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *); 1636 extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *); 1637 extern void jbd2_journal_write_revoke_records(transaction_t *transaction, 1638 struct list_head *log_bufs); 1639 1640 /* Recovery revoke support */ 1641 extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t); 1642 extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t); 1643 extern void jbd2_journal_clear_revoke(journal_t *); 1644 extern void jbd2_journal_switch_revoke_table(journal_t *journal); 1645 extern void jbd2_clear_buffer_revoked_flags(journal_t *journal); 1646 1647 /* 1648 * The log thread user interface: 1649 * 1650 * Request space in the current transaction, and force transaction commit 1651 * transitions on demand. 1652 */ 1653 1654 int jbd2_log_start_commit(journal_t *journal, tid_t tid); 1655 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid); 1656 int jbd2_log_wait_commit(journal_t *journal, tid_t tid); 1657 int jbd2_transaction_committed(journal_t *journal, tid_t tid); 1658 int jbd2_complete_transaction(journal_t *journal, tid_t tid); 1659 int jbd2_log_do_checkpoint(journal_t *journal); 1660 int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid); 1661 1662 void __jbd2_log_wait_for_space(journal_t *journal); 1663 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *); 1664 extern int jbd2_cleanup_journal_tail(journal_t *); 1665 1666 /* Fast commit related APIs */ 1667 int jbd2_fc_begin_commit(journal_t *journal, tid_t tid); 1668 int jbd2_fc_end_commit(journal_t *journal); 1669 int jbd2_fc_end_commit_fallback(journal_t *journal); 1670 int jbd2_fc_get_buf(journal_t *journal, struct buffer_head **bh_out); 1671 int jbd2_submit_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1672 int jbd2_wait_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1673 int jbd2_fc_wait_bufs(journal_t *journal, int num_blks); 1674 int jbd2_fc_release_bufs(journal_t *journal); 1675 1676 static inline int jbd2_journal_get_max_txn_bufs(journal_t *journal) 1677 { 1678 return (journal->j_total_len - journal->j_fc_wbufsize) / 4; 1679 } 1680 1681 /* 1682 * is_journal_abort 1683 * 1684 * Simple test wrapper function to test the JBD2_ABORT state flag. This 1685 * bit, when set, indicates that we have had a fatal error somewhere, 1686 * either inside the journaling layer or indicated to us by the client 1687 * (eg. ext3), and that we and should not commit any further 1688 * transactions. 1689 */ 1690 1691 static inline int is_journal_aborted(journal_t *journal) 1692 { 1693 return journal->j_flags & JBD2_ABORT; 1694 } 1695 1696 static inline int is_handle_aborted(handle_t *handle) 1697 { 1698 if (handle->h_aborted || !handle->h_transaction) 1699 return 1; 1700 return is_journal_aborted(handle->h_transaction->t_journal); 1701 } 1702 1703 static inline void jbd2_journal_abort_handle(handle_t *handle) 1704 { 1705 handle->h_aborted = 1; 1706 } 1707 1708 #endif /* __KERNEL__ */ 1709 1710 /* Comparison functions for transaction IDs: perform comparisons using 1711 * modulo arithmetic so that they work over sequence number wraps. */ 1712 1713 static inline int tid_gt(tid_t x, tid_t y) 1714 { 1715 int difference = (x - y); 1716 return (difference > 0); 1717 } 1718 1719 static inline int tid_geq(tid_t x, tid_t y) 1720 { 1721 int difference = (x - y); 1722 return (difference >= 0); 1723 } 1724 1725 extern int jbd2_journal_blocks_per_page(struct inode *inode); 1726 extern size_t journal_tag_bytes(journal_t *journal); 1727 1728 static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j) 1729 { 1730 return jbd2_has_feature_csum2(j) || jbd2_has_feature_csum3(j); 1731 } 1732 1733 static inline int jbd2_journal_has_csum_v2or3(journal_t *journal) 1734 { 1735 WARN_ON_ONCE(jbd2_journal_has_csum_v2or3_feature(journal) && 1736 journal->j_chksum_driver == NULL); 1737 1738 return journal->j_chksum_driver != NULL; 1739 } 1740 1741 static inline int jbd2_journal_get_num_fc_blks(journal_superblock_t *jsb) 1742 { 1743 int num_fc_blocks = be32_to_cpu(jsb->s_num_fc_blks); 1744 1745 return num_fc_blocks ? num_fc_blocks : JBD2_DEFAULT_FAST_COMMIT_BLOCKS; 1746 } 1747 1748 /* 1749 * Return number of free blocks in the log. Must be called under j_state_lock. 1750 */ 1751 static inline unsigned long jbd2_log_space_left(journal_t *journal) 1752 { 1753 /* Allow for rounding errors */ 1754 long free = journal->j_free - 32; 1755 1756 if (journal->j_committing_transaction) { 1757 free -= atomic_read(&journal-> 1758 j_committing_transaction->t_outstanding_credits); 1759 } 1760 return max_t(long, free, 0); 1761 } 1762 1763 /* 1764 * Definitions which augment the buffer_head layer 1765 */ 1766 1767 /* journaling buffer types */ 1768 #define BJ_None 0 /* Not journaled */ 1769 #define BJ_Metadata 1 /* Normal journaled metadata */ 1770 #define BJ_Forget 2 /* Buffer superseded by this transaction */ 1771 #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */ 1772 #define BJ_Reserved 4 /* Buffer is reserved for access by journal */ 1773 #define BJ_Types 5 1774 1775 /* JBD uses a CRC32 checksum */ 1776 #define JBD_MAX_CHECKSUM_SIZE 4 1777 1778 static inline u32 jbd2_chksum(journal_t *journal, u32 crc, 1779 const void *address, unsigned int length) 1780 { 1781 struct { 1782 struct shash_desc shash; 1783 char ctx[JBD_MAX_CHECKSUM_SIZE]; 1784 } desc; 1785 int err; 1786 1787 BUG_ON(crypto_shash_descsize(journal->j_chksum_driver) > 1788 JBD_MAX_CHECKSUM_SIZE); 1789 1790 desc.shash.tfm = journal->j_chksum_driver; 1791 *(u32 *)desc.ctx = crc; 1792 1793 err = crypto_shash_update(&desc.shash, address, length); 1794 BUG_ON(err); 1795 1796 return *(u32 *)desc.ctx; 1797 } 1798 1799 /* Return most recent uncommitted transaction */ 1800 static inline tid_t jbd2_get_latest_transaction(journal_t *journal) 1801 { 1802 tid_t tid; 1803 1804 read_lock(&journal->j_state_lock); 1805 tid = journal->j_commit_request; 1806 if (journal->j_running_transaction) 1807 tid = journal->j_running_transaction->t_tid; 1808 read_unlock(&journal->j_state_lock); 1809 return tid; 1810 } 1811 1812 static inline int jbd2_handle_buffer_credits(handle_t *handle) 1813 { 1814 journal_t *journal; 1815 1816 if (!handle->h_reserved) 1817 journal = handle->h_transaction->t_journal; 1818 else 1819 journal = handle->h_journal; 1820 1821 return handle->h_total_credits - 1822 DIV_ROUND_UP(handle->h_revoke_credits_requested, 1823 journal->j_revoke_records_per_block); 1824 } 1825 1826 #ifdef __KERNEL__ 1827 1828 #define buffer_trace_init(bh) do {} while (0) 1829 #define print_buffer_fields(bh) do {} while (0) 1830 #define print_buffer_trace(bh) do {} while (0) 1831 #define BUFFER_TRACE(bh, info) do {} while (0) 1832 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0) 1833 #define JBUFFER_TRACE(jh, info) do {} while (0) 1834 1835 #endif /* __KERNEL__ */ 1836 1837 #define EFSBADCRC EBADMSG /* Bad CRC detected */ 1838 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ 1839 1840 #endif /* _LINUX_JBD2_H */ 1841