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 __be32 s_head; /* blocknr of head of log, only uptodate 269 * while the filesystem is clean */ 270 /* 0x005C */ 271 __u32 s_padding[40]; 272 __be32 s_checksum; /* crc32c(superblock) */ 273 274 /* 0x0100 */ 275 __u8 s_users[16*48]; /* ids of all fs'es sharing the log */ 276 /* 0x0400 */ 277 } journal_superblock_t; 278 279 #define JBD2_FEATURE_COMPAT_CHECKSUM 0x00000001 280 281 #define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001 282 #define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002 283 #define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT 0x00000004 284 #define JBD2_FEATURE_INCOMPAT_CSUM_V2 0x00000008 285 #define JBD2_FEATURE_INCOMPAT_CSUM_V3 0x00000010 286 #define JBD2_FEATURE_INCOMPAT_FAST_COMMIT 0x00000020 287 288 /* See "journal feature predicate functions" below */ 289 290 /* Features known to this kernel version: */ 291 #define JBD2_KNOWN_COMPAT_FEATURES JBD2_FEATURE_COMPAT_CHECKSUM 292 #define JBD2_KNOWN_ROCOMPAT_FEATURES 0 293 #define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \ 294 JBD2_FEATURE_INCOMPAT_64BIT | \ 295 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | \ 296 JBD2_FEATURE_INCOMPAT_CSUM_V2 | \ 297 JBD2_FEATURE_INCOMPAT_CSUM_V3 | \ 298 JBD2_FEATURE_INCOMPAT_FAST_COMMIT) 299 300 #ifdef __KERNEL__ 301 302 #include <linux/fs.h> 303 #include <linux/sched.h> 304 305 enum jbd_state_bits { 306 BH_JBD /* Has an attached ext3 journal_head */ 307 = BH_PrivateStart, 308 BH_JWrite, /* Being written to log (@@@ DEBUGGING) */ 309 BH_Freed, /* Has been freed (truncated) */ 310 BH_Revoked, /* Has been revoked from the log */ 311 BH_RevokeValid, /* Revoked flag is valid */ 312 BH_JBDDirty, /* Is dirty but journaled */ 313 BH_JournalHead, /* Pins bh->b_private and jh->b_bh */ 314 BH_Shadow, /* IO on shadow buffer is running */ 315 BH_Verified, /* Metadata block has been verified ok */ 316 BH_JBDPrivateStart, /* First bit available for private use by FS */ 317 }; 318 319 BUFFER_FNS(JBD, jbd) 320 BUFFER_FNS(JWrite, jwrite) 321 BUFFER_FNS(JBDDirty, jbddirty) 322 TAS_BUFFER_FNS(JBDDirty, jbddirty) 323 BUFFER_FNS(Revoked, revoked) 324 TAS_BUFFER_FNS(Revoked, revoked) 325 BUFFER_FNS(RevokeValid, revokevalid) 326 TAS_BUFFER_FNS(RevokeValid, revokevalid) 327 BUFFER_FNS(Freed, freed) 328 BUFFER_FNS(Shadow, shadow) 329 BUFFER_FNS(Verified, verified) 330 331 static inline struct buffer_head *jh2bh(struct journal_head *jh) 332 { 333 return jh->b_bh; 334 } 335 336 static inline struct journal_head *bh2jh(struct buffer_head *bh) 337 { 338 return bh->b_private; 339 } 340 341 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh) 342 { 343 bit_spin_lock(BH_JournalHead, &bh->b_state); 344 } 345 346 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh) 347 { 348 bit_spin_unlock(BH_JournalHead, &bh->b_state); 349 } 350 351 #define J_ASSERT(assert) BUG_ON(!(assert)) 352 353 #define J_ASSERT_BH(bh, expr) J_ASSERT(expr) 354 #define J_ASSERT_JH(jh, expr) J_ASSERT(expr) 355 356 #if defined(JBD2_PARANOID_IOFAIL) 357 #define J_EXPECT(expr, why...) J_ASSERT(expr) 358 #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr) 359 #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr) 360 #else 361 #define __journal_expect(expr, why...) \ 362 ({ \ 363 int val = (expr); \ 364 if (!val) { \ 365 printk(KERN_ERR \ 366 "JBD2 unexpected failure: %s: %s;\n", \ 367 __func__, #expr); \ 368 printk(KERN_ERR why "\n"); \ 369 } \ 370 val; \ 371 }) 372 #define J_EXPECT(expr, why...) __journal_expect(expr, ## why) 373 #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why) 374 #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why) 375 #endif 376 377 /* Flags in jbd_inode->i_flags */ 378 #define __JI_COMMIT_RUNNING 0 379 #define __JI_WRITE_DATA 1 380 #define __JI_WAIT_DATA 2 381 382 /* 383 * Commit of the inode data in progress. We use this flag to protect us from 384 * concurrent deletion of inode. We cannot use reference to inode for this 385 * since we cannot afford doing last iput() on behalf of kjournald 386 */ 387 #define JI_COMMIT_RUNNING (1 << __JI_COMMIT_RUNNING) 388 /* Write allocated dirty buffers in this inode before commit */ 389 #define JI_WRITE_DATA (1 << __JI_WRITE_DATA) 390 /* Wait for outstanding data writes for this inode before commit */ 391 #define JI_WAIT_DATA (1 << __JI_WAIT_DATA) 392 393 /** 394 * struct jbd2_inode - The jbd_inode type is the structure linking inodes in 395 * ordered mode present in a transaction so that we can sync them during commit. 396 */ 397 struct jbd2_inode { 398 /** 399 * @i_transaction: 400 * 401 * Which transaction does this inode belong to? Either the running 402 * transaction or the committing one. [j_list_lock] 403 */ 404 transaction_t *i_transaction; 405 406 /** 407 * @i_next_transaction: 408 * 409 * Pointer to the running transaction modifying inode's data in case 410 * there is already a committing transaction touching it. [j_list_lock] 411 */ 412 transaction_t *i_next_transaction; 413 414 /** 415 * @i_list: List of inodes in the i_transaction [j_list_lock] 416 */ 417 struct list_head i_list; 418 419 /** 420 * @i_vfs_inode: 421 * 422 * VFS inode this inode belongs to [constant for lifetime of structure] 423 */ 424 struct inode *i_vfs_inode; 425 426 /** 427 * @i_flags: Flags of inode [j_list_lock] 428 */ 429 unsigned long i_flags; 430 431 /** 432 * @i_dirty_start: 433 * 434 * Offset in bytes where the dirty range for this inode starts. 435 * [j_list_lock] 436 */ 437 loff_t i_dirty_start; 438 439 /** 440 * @i_dirty_end: 441 * 442 * Inclusive offset in bytes where the dirty range for this inode 443 * ends. [j_list_lock] 444 */ 445 loff_t i_dirty_end; 446 }; 447 448 struct jbd2_revoke_table_s; 449 450 /** 451 * struct jbd2_journal_handle - The jbd2_journal_handle type is the concrete 452 * type associated with handle_t. 453 * @h_transaction: Which compound transaction is this update a part of? 454 * @h_journal: Which journal handle belongs to - used iff h_reserved set. 455 * @h_rsv_handle: Handle reserved for finishing the logical operation. 456 * @h_total_credits: Number of remaining buffers we are allowed to add to 457 * journal. These are dirty buffers and revoke descriptor blocks. 458 * @h_revoke_credits: Number of remaining revoke records available for handle 459 * @h_ref: Reference count on this handle. 460 * @h_err: Field for caller's use to track errors through large fs operations. 461 * @h_sync: Flag for sync-on-close. 462 * @h_jdata: Flag to force data journaling. 463 * @h_reserved: Flag for handle for reserved credits. 464 * @h_aborted: Flag indicating fatal error on handle. 465 * @h_type: For handle statistics. 466 * @h_line_no: For handle statistics. 467 * @h_start_jiffies: Handle Start time. 468 * @h_requested_credits: Holds @h_total_credits after handle is started. 469 * @h_revoke_credits_requested: Holds @h_revoke_credits after handle is started. 470 * @saved_alloc_context: Saved context while transaction is open. 471 **/ 472 473 /* Docbook can't yet cope with the bit fields, but will leave the documentation 474 * in so it can be fixed later. 475 */ 476 477 struct jbd2_journal_handle 478 { 479 union { 480 transaction_t *h_transaction; 481 /* Which journal handle belongs to - used iff h_reserved set */ 482 journal_t *h_journal; 483 }; 484 485 handle_t *h_rsv_handle; 486 int h_total_credits; 487 int h_revoke_credits; 488 int h_revoke_credits_requested; 489 int h_ref; 490 int h_err; 491 492 /* Flags [no locking] */ 493 unsigned int h_sync: 1; 494 unsigned int h_jdata: 1; 495 unsigned int h_reserved: 1; 496 unsigned int h_aborted: 1; 497 unsigned int h_type: 8; 498 unsigned int h_line_no: 16; 499 500 unsigned long h_start_jiffies; 501 unsigned int h_requested_credits; 502 503 unsigned int saved_alloc_context; 504 }; 505 506 507 /* 508 * Some stats for checkpoint phase 509 */ 510 struct transaction_chp_stats_s { 511 unsigned long cs_chp_time; 512 __u32 cs_forced_to_close; 513 __u32 cs_written; 514 __u32 cs_dropped; 515 }; 516 517 /* The transaction_t type is the guts of the journaling mechanism. It 518 * tracks a compound transaction through its various states: 519 * 520 * RUNNING: accepting new updates 521 * LOCKED: Updates still running but we don't accept new ones 522 * RUNDOWN: Updates are tidying up but have finished requesting 523 * new buffers to modify (state not used for now) 524 * FLUSH: All updates complete, but we are still writing to disk 525 * COMMIT: All data on disk, writing commit record 526 * FINISHED: We still have to keep the transaction for checkpointing. 527 * 528 * The transaction keeps track of all of the buffers modified by a 529 * running transaction, and all of the buffers committed but not yet 530 * flushed to home for finished transactions. 531 * (Locking Documentation improved by LockDoc) 532 */ 533 534 /* 535 * Lock ranking: 536 * 537 * j_list_lock 538 * ->jbd_lock_bh_journal_head() (This is "innermost") 539 * 540 * j_state_lock 541 * ->b_state_lock 542 * 543 * b_state_lock 544 * ->j_list_lock 545 * 546 * j_state_lock 547 * ->j_list_lock (journal_unmap_buffer) 548 * 549 */ 550 551 struct transaction_s 552 { 553 /* Pointer to the journal for this transaction. [no locking] */ 554 journal_t *t_journal; 555 556 /* Sequence number for this transaction [no locking] */ 557 tid_t t_tid; 558 559 /* 560 * Transaction's current state 561 * [no locking - only kjournald2 alters this] 562 * [j_list_lock] guards transition of a transaction into T_FINISHED 563 * state and subsequent call of __jbd2_journal_drop_transaction() 564 * FIXME: needs barriers 565 * KLUDGE: [use j_state_lock] 566 */ 567 enum { 568 T_RUNNING, 569 T_LOCKED, 570 T_SWITCH, 571 T_FLUSH, 572 T_COMMIT, 573 T_COMMIT_DFLUSH, 574 T_COMMIT_JFLUSH, 575 T_COMMIT_CALLBACK, 576 T_FINISHED 577 } t_state; 578 579 /* 580 * Where in the log does this transaction's commit start? [no locking] 581 */ 582 unsigned long t_log_start; 583 584 /* 585 * Number of buffers on the t_buffers list [j_list_lock, no locks 586 * needed for jbd2 thread] 587 */ 588 int t_nr_buffers; 589 590 /* 591 * Doubly-linked circular list of all buffers reserved but not yet 592 * modified by this transaction [j_list_lock, no locks needed fo 593 * jbd2 thread] 594 */ 595 struct journal_head *t_reserved_list; 596 597 /* 598 * Doubly-linked circular list of all metadata buffers owned by this 599 * transaction [j_list_lock, no locks needed for jbd2 thread] 600 */ 601 struct journal_head *t_buffers; 602 603 /* 604 * Doubly-linked circular list of all forget buffers (superseded 605 * buffers which we can un-checkpoint once this transaction commits) 606 * [j_list_lock] 607 */ 608 struct journal_head *t_forget; 609 610 /* 611 * Doubly-linked circular list of all buffers still to be flushed before 612 * this transaction can be checkpointed. [j_list_lock] 613 */ 614 struct journal_head *t_checkpoint_list; 615 616 /* 617 * Doubly-linked circular list of metadata buffers being 618 * shadowed by log IO. The IO buffers on the iobuf list and 619 * the shadow buffers on this list match each other one for 620 * one at all times. [j_list_lock, no locks needed for jbd2 621 * thread] 622 */ 623 struct journal_head *t_shadow_list; 624 625 /* 626 * List of inodes associated with the transaction; e.g., ext4 uses 627 * this to track inodes in data=ordered and data=journal mode that 628 * need special handling on transaction commit; also used by ocfs2. 629 * [j_list_lock] 630 */ 631 struct list_head t_inode_list; 632 633 /* 634 * Protects info related to handles 635 */ 636 spinlock_t t_handle_lock; 637 638 /* 639 * Longest time some handle had to wait for running transaction 640 */ 641 unsigned long t_max_wait; 642 643 /* 644 * When transaction started 645 */ 646 unsigned long t_start; 647 648 /* 649 * When commit was requested [j_state_lock] 650 */ 651 unsigned long t_requested; 652 653 /* 654 * Checkpointing stats [j_list_lock] 655 */ 656 struct transaction_chp_stats_s t_chp_stats; 657 658 /* 659 * Number of outstanding updates running on this transaction 660 * [none] 661 */ 662 atomic_t t_updates; 663 664 /* 665 * Number of blocks reserved for this transaction in the journal. 666 * This is including all credits reserved when starting transaction 667 * handles as well as all journal descriptor blocks needed for this 668 * transaction. [none] 669 */ 670 atomic_t t_outstanding_credits; 671 672 /* 673 * Number of revoke records for this transaction added by already 674 * stopped handles. [none] 675 */ 676 atomic_t t_outstanding_revokes; 677 678 /* 679 * How many handles used this transaction? [none] 680 */ 681 atomic_t t_handle_count; 682 683 /* 684 * Forward and backward links for the circular list of all transactions 685 * awaiting checkpoint. [j_list_lock] 686 */ 687 transaction_t *t_cpnext, *t_cpprev; 688 689 /* 690 * When will the transaction expire (become due for commit), in jiffies? 691 * [no locking] 692 */ 693 unsigned long t_expires; 694 695 /* 696 * When this transaction started, in nanoseconds [no locking] 697 */ 698 ktime_t t_start_time; 699 700 /* 701 * This transaction is being forced and some process is 702 * waiting for it to finish. 703 */ 704 unsigned int t_synchronous_commit:1; 705 706 /* Disk flush needs to be sent to fs partition [no locking] */ 707 int t_need_data_flush; 708 709 /* 710 * For use by the filesystem to store fs-specific data 711 * structures associated with the transaction 712 */ 713 struct list_head t_private_list; 714 }; 715 716 struct transaction_run_stats_s { 717 unsigned long rs_wait; 718 unsigned long rs_request_delay; 719 unsigned long rs_running; 720 unsigned long rs_locked; 721 unsigned long rs_flushing; 722 unsigned long rs_logging; 723 724 __u32 rs_handle_count; 725 __u32 rs_blocks; 726 __u32 rs_blocks_logged; 727 }; 728 729 struct transaction_stats_s { 730 unsigned long ts_tid; 731 unsigned long ts_requested; 732 struct transaction_run_stats_s run; 733 }; 734 735 static inline unsigned long 736 jbd2_time_diff(unsigned long start, unsigned long end) 737 { 738 if (end >= start) 739 return end - start; 740 741 return end + (MAX_JIFFY_OFFSET - start); 742 } 743 744 #define JBD2_NR_BATCH 64 745 746 enum passtype {PASS_SCAN, PASS_REVOKE, PASS_REPLAY}; 747 748 #define JBD2_FC_REPLAY_STOP 0 749 #define JBD2_FC_REPLAY_CONTINUE 1 750 751 /** 752 * struct journal_s - The journal_s type is the concrete type associated with 753 * journal_t. 754 */ 755 struct journal_s 756 { 757 /** 758 * @j_flags: General journaling state flags [j_state_lock, 759 * no lock for quick racy checks] 760 */ 761 unsigned long j_flags; 762 763 /** 764 * @j_atomic_flags: Atomic journaling state flags. 765 */ 766 unsigned long j_atomic_flags; 767 768 /** 769 * @j_errno: 770 * 771 * Is there an outstanding uncleared error on the journal (from a prior 772 * abort)? [j_state_lock] 773 */ 774 int j_errno; 775 776 /** 777 * @j_abort_mutex: Lock the whole aborting procedure. 778 */ 779 struct mutex j_abort_mutex; 780 781 /** 782 * @j_sb_buffer: The first part of the superblock buffer. 783 */ 784 struct buffer_head *j_sb_buffer; 785 786 /** 787 * @j_superblock: The second part of the superblock buffer. 788 */ 789 journal_superblock_t *j_superblock; 790 791 /** 792 * @j_state_lock: Protect the various scalars in the journal. 793 */ 794 rwlock_t j_state_lock; 795 796 /** 797 * @j_barrier_count: 798 * 799 * Number of processes waiting to create a barrier lock [j_state_lock, 800 * no lock for quick racy checks] 801 */ 802 int j_barrier_count; 803 804 /** 805 * @j_barrier: The barrier lock itself. 806 */ 807 struct mutex j_barrier; 808 809 /** 810 * @j_running_transaction: 811 * 812 * Transactions: The current running transaction... 813 * [j_state_lock, no lock for quick racy checks] [caller holding 814 * open handle] 815 */ 816 transaction_t *j_running_transaction; 817 818 /** 819 * @j_committing_transaction: 820 * 821 * the transaction we are pushing to disk 822 * [j_state_lock] [caller holding open handle] 823 */ 824 transaction_t *j_committing_transaction; 825 826 /** 827 * @j_checkpoint_transactions: 828 * 829 * ... and a linked circular list of all transactions waiting for 830 * checkpointing. [j_list_lock] 831 */ 832 transaction_t *j_checkpoint_transactions; 833 834 /** 835 * @j_wait_transaction_locked: 836 * 837 * Wait queue for waiting for a locked transaction to start committing, 838 * or for a barrier lock to be released. 839 */ 840 wait_queue_head_t j_wait_transaction_locked; 841 842 /** 843 * @j_wait_done_commit: Wait queue for waiting for commit to complete. 844 */ 845 wait_queue_head_t j_wait_done_commit; 846 847 /** 848 * @j_wait_commit: Wait queue to trigger commit. 849 */ 850 wait_queue_head_t j_wait_commit; 851 852 /** 853 * @j_wait_updates: Wait queue to wait for updates to complete. 854 */ 855 wait_queue_head_t j_wait_updates; 856 857 /** 858 * @j_wait_reserved: 859 * 860 * Wait queue to wait for reserved buffer credits to drop. 861 */ 862 wait_queue_head_t j_wait_reserved; 863 864 /** 865 * @j_fc_wait: 866 * 867 * Wait queue to wait for completion of async fast commits. 868 */ 869 wait_queue_head_t j_fc_wait; 870 871 /** 872 * @j_checkpoint_mutex: 873 * 874 * Semaphore for locking against concurrent checkpoints. 875 */ 876 struct mutex j_checkpoint_mutex; 877 878 /** 879 * @j_chkpt_bhs: 880 * 881 * List of buffer heads used by the checkpoint routine. This 882 * was moved from jbd2_log_do_checkpoint() to reduce stack 883 * usage. Access to this array is controlled by the 884 * @j_checkpoint_mutex. [j_checkpoint_mutex] 885 */ 886 struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH]; 887 888 /** 889 * @j_shrinker: 890 * 891 * Journal head shrinker, reclaim buffer's journal head which 892 * has been written back. 893 */ 894 struct shrinker j_shrinker; 895 896 /** 897 * @j_checkpoint_jh_count: 898 * 899 * Number of journal buffers on the checkpoint list. [j_list_lock] 900 */ 901 struct percpu_counter j_checkpoint_jh_count; 902 903 /** 904 * @j_shrink_transaction: 905 * 906 * Record next transaction will shrink on the checkpoint list. 907 * [j_list_lock] 908 */ 909 transaction_t *j_shrink_transaction; 910 911 /** 912 * @j_head: 913 * 914 * Journal head: identifies the first unused block in the journal. 915 * [j_state_lock] 916 */ 917 unsigned long j_head; 918 919 /** 920 * @j_tail: 921 * 922 * Journal tail: identifies the oldest still-used block in the journal. 923 * [j_state_lock] 924 */ 925 unsigned long j_tail; 926 927 /** 928 * @j_free: 929 * 930 * Journal free: how many free blocks are there in the journal? 931 * [j_state_lock] 932 */ 933 unsigned long j_free; 934 935 /** 936 * @j_first: 937 * 938 * The block number of the first usable block in the journal 939 * [j_state_lock]. 940 */ 941 unsigned long j_first; 942 943 /** 944 * @j_last: 945 * 946 * The block number one beyond the last usable block in the journal 947 * [j_state_lock]. 948 */ 949 unsigned long j_last; 950 951 /** 952 * @j_fc_first: 953 * 954 * The block number of the first fast commit block in the journal 955 * [j_state_lock]. 956 */ 957 unsigned long j_fc_first; 958 959 /** 960 * @j_fc_off: 961 * 962 * Number of fast commit blocks currently allocated. Accessed only 963 * during fast commit. Currently only process can do fast commit, so 964 * this field is not protected by any lock. 965 */ 966 unsigned long j_fc_off; 967 968 /** 969 * @j_fc_last: 970 * 971 * The block number one beyond the last fast commit block in the journal 972 * [j_state_lock]. 973 */ 974 unsigned long j_fc_last; 975 976 /** 977 * @j_dev: Device where we store the journal. 978 */ 979 struct block_device *j_dev; 980 981 /** 982 * @j_blocksize: Block size for the location where we store the journal. 983 */ 984 int j_blocksize; 985 986 /** 987 * @j_blk_offset: 988 * 989 * Starting block offset into the device where we store the journal. 990 */ 991 unsigned long long j_blk_offset; 992 993 /** 994 * @j_devname: Journal device name. 995 */ 996 char j_devname[BDEVNAME_SIZE+24]; 997 998 /** 999 * @j_fs_dev: 1000 * 1001 * Device which holds the client fs. For internal journal this will be 1002 * equal to j_dev. 1003 */ 1004 struct block_device *j_fs_dev; 1005 1006 /** 1007 * @j_total_len: Total maximum capacity of the journal region on disk. 1008 */ 1009 unsigned int j_total_len; 1010 1011 /** 1012 * @j_reserved_credits: 1013 * 1014 * Number of buffers reserved from the running transaction. 1015 */ 1016 atomic_t j_reserved_credits; 1017 1018 /** 1019 * @j_list_lock: Protects the buffer lists and internal buffer state. 1020 */ 1021 spinlock_t j_list_lock; 1022 1023 /** 1024 * @j_inode: 1025 * 1026 * Optional inode where we store the journal. If present, all 1027 * journal block numbers are mapped into this inode via bmap(). 1028 */ 1029 struct inode *j_inode; 1030 1031 /** 1032 * @j_tail_sequence: 1033 * 1034 * Sequence number of the oldest transaction in the log [j_state_lock] 1035 */ 1036 tid_t j_tail_sequence; 1037 1038 /** 1039 * @j_transaction_sequence: 1040 * 1041 * Sequence number of the next transaction to grant [j_state_lock] 1042 */ 1043 tid_t j_transaction_sequence; 1044 1045 /** 1046 * @j_commit_sequence: 1047 * 1048 * Sequence number of the most recently committed transaction 1049 * [j_state_lock, no lock for quick racy checks] 1050 */ 1051 tid_t j_commit_sequence; 1052 1053 /** 1054 * @j_commit_request: 1055 * 1056 * Sequence number of the most recent transaction wanting commit 1057 * [j_state_lock, no lock for quick racy checks] 1058 */ 1059 tid_t j_commit_request; 1060 1061 /** 1062 * @j_uuid: 1063 * 1064 * Journal uuid: identifies the object (filesystem, LVM volume etc) 1065 * backed by this journal. This will eventually be replaced by an array 1066 * of uuids, allowing us to index multiple devices within a single 1067 * journal and to perform atomic updates across them. 1068 */ 1069 __u8 j_uuid[16]; 1070 1071 /** 1072 * @j_task: Pointer to the current commit thread for this journal. 1073 */ 1074 struct task_struct *j_task; 1075 1076 /** 1077 * @j_max_transaction_buffers: 1078 * 1079 * Maximum number of metadata buffers to allow in a single compound 1080 * commit transaction. 1081 */ 1082 int j_max_transaction_buffers; 1083 1084 /** 1085 * @j_revoke_records_per_block: 1086 * 1087 * Number of revoke records that fit in one descriptor block. 1088 */ 1089 int j_revoke_records_per_block; 1090 1091 /** 1092 * @j_commit_interval: 1093 * 1094 * What is the maximum transaction lifetime before we begin a commit? 1095 */ 1096 unsigned long j_commit_interval; 1097 1098 /** 1099 * @j_commit_timer: The timer used to wakeup the commit thread. 1100 */ 1101 struct timer_list j_commit_timer; 1102 1103 /** 1104 * @j_revoke_lock: Protect the revoke table. 1105 */ 1106 spinlock_t j_revoke_lock; 1107 1108 /** 1109 * @j_revoke: 1110 * 1111 * The revoke table - maintains the list of revoked blocks in the 1112 * current transaction. 1113 */ 1114 struct jbd2_revoke_table_s *j_revoke; 1115 1116 /** 1117 * @j_revoke_table: Alternate revoke tables for j_revoke. 1118 */ 1119 struct jbd2_revoke_table_s *j_revoke_table[2]; 1120 1121 /** 1122 * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction. 1123 */ 1124 struct buffer_head **j_wbuf; 1125 1126 /** 1127 * @j_fc_wbuf: Array of fast commit bhs for fast commit. Accessed only 1128 * during a fast commit. Currently only process can do fast commit, so 1129 * this field is not protected by any lock. 1130 */ 1131 struct buffer_head **j_fc_wbuf; 1132 1133 /** 1134 * @j_wbufsize: 1135 * 1136 * Size of @j_wbuf array. 1137 */ 1138 int j_wbufsize; 1139 1140 /** 1141 * @j_fc_wbufsize: 1142 * 1143 * Size of @j_fc_wbuf array. 1144 */ 1145 int j_fc_wbufsize; 1146 1147 /** 1148 * @j_last_sync_writer: 1149 * 1150 * The pid of the last person to run a synchronous operation 1151 * through the journal. 1152 */ 1153 pid_t j_last_sync_writer; 1154 1155 /** 1156 * @j_average_commit_time: 1157 * 1158 * The average amount of time in nanoseconds it takes to commit a 1159 * transaction to disk. [j_state_lock] 1160 */ 1161 u64 j_average_commit_time; 1162 1163 /** 1164 * @j_min_batch_time: 1165 * 1166 * Minimum time that we should wait for additional filesystem operations 1167 * to get batched into a synchronous handle in microseconds. 1168 */ 1169 u32 j_min_batch_time; 1170 1171 /** 1172 * @j_max_batch_time: 1173 * 1174 * Maximum time that we should wait for additional filesystem operations 1175 * to get batched into a synchronous handle in microseconds. 1176 */ 1177 u32 j_max_batch_time; 1178 1179 /** 1180 * @j_commit_callback: 1181 * 1182 * This function is called when a transaction is closed. 1183 */ 1184 void (*j_commit_callback)(journal_t *, 1185 transaction_t *); 1186 1187 /** 1188 * @j_submit_inode_data_buffers: 1189 * 1190 * This function is called for all inodes associated with the 1191 * committing transaction marked with JI_WRITE_DATA flag 1192 * before we start to write out the transaction to the journal. 1193 */ 1194 int (*j_submit_inode_data_buffers) 1195 (struct jbd2_inode *); 1196 1197 /** 1198 * @j_finish_inode_data_buffers: 1199 * 1200 * This function is called for all inodes associated with the 1201 * committing transaction marked with JI_WAIT_DATA flag 1202 * after we have written the transaction to the journal 1203 * but before we write out the commit block. 1204 */ 1205 int (*j_finish_inode_data_buffers) 1206 (struct jbd2_inode *); 1207 1208 /* 1209 * Journal statistics 1210 */ 1211 1212 /** 1213 * @j_history_lock: Protect the transactions statistics history. 1214 */ 1215 spinlock_t j_history_lock; 1216 1217 /** 1218 * @j_proc_entry: procfs entry for the jbd statistics directory. 1219 */ 1220 struct proc_dir_entry *j_proc_entry; 1221 1222 /** 1223 * @j_stats: Overall statistics. 1224 */ 1225 struct transaction_stats_s j_stats; 1226 1227 /** 1228 * @j_failed_commit: Failed journal commit ID. 1229 */ 1230 unsigned int j_failed_commit; 1231 1232 /** 1233 * @j_private: 1234 * 1235 * An opaque pointer to fs-private information. ext3 puts its 1236 * superblock pointer here. 1237 */ 1238 void *j_private; 1239 1240 /** 1241 * @j_chksum_driver: 1242 * 1243 * Reference to checksum algorithm driver via cryptoapi. 1244 */ 1245 struct crypto_shash *j_chksum_driver; 1246 1247 /** 1248 * @j_csum_seed: 1249 * 1250 * Precomputed journal UUID checksum for seeding other checksums. 1251 */ 1252 __u32 j_csum_seed; 1253 1254 #ifdef CONFIG_DEBUG_LOCK_ALLOC 1255 /** 1256 * @j_trans_commit_map: 1257 * 1258 * Lockdep entity to track transaction commit dependencies. Handles 1259 * hold this "lock" for read, when we wait for commit, we acquire the 1260 * "lock" for writing. This matches the properties of jbd2 journalling 1261 * where the running transaction has to wait for all handles to be 1262 * dropped to commit that transaction and also acquiring a handle may 1263 * require transaction commit to finish. 1264 */ 1265 struct lockdep_map j_trans_commit_map; 1266 #endif 1267 1268 /** 1269 * @j_fc_cleanup_callback: 1270 * 1271 * Clean-up after fast commit or full commit. JBD2 calls this function 1272 * after every commit operation. 1273 */ 1274 void (*j_fc_cleanup_callback)(struct journal_s *journal, int full, tid_t tid); 1275 1276 /** 1277 * @j_fc_replay_callback: 1278 * 1279 * File-system specific function that performs replay of a fast 1280 * commit. JBD2 calls this function for each fast commit block found in 1281 * the journal. This function should return JBD2_FC_REPLAY_CONTINUE 1282 * to indicate that the block was processed correctly and more fast 1283 * commit replay should continue. Return value of JBD2_FC_REPLAY_STOP 1284 * indicates the end of replay (no more blocks remaining). A negative 1285 * return value indicates error. 1286 */ 1287 int (*j_fc_replay_callback)(struct journal_s *journal, 1288 struct buffer_head *bh, 1289 enum passtype pass, int off, 1290 tid_t expected_commit_id); 1291 1292 /** 1293 * @j_bmap: 1294 * 1295 * Bmap function that should be used instead of the generic 1296 * VFS bmap function. 1297 */ 1298 int (*j_bmap)(struct journal_s *journal, sector_t *block); 1299 }; 1300 1301 #define jbd2_might_wait_for_commit(j) \ 1302 do { \ 1303 rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \ 1304 rwsem_release(&j->j_trans_commit_map, _THIS_IP_); \ 1305 } while (0) 1306 1307 /* 1308 * We can support any known requested features iff the 1309 * superblock is not in version 1. Otherwise we fail to support any 1310 * extended sb features. 1311 */ 1312 static inline bool jbd2_format_support_feature(journal_t *j) 1313 { 1314 return j->j_superblock->s_header.h_blocktype != 1315 cpu_to_be32(JBD2_SUPERBLOCK_V1); 1316 } 1317 1318 /* journal feature predicate functions */ 1319 #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \ 1320 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1321 { \ 1322 return (jbd2_format_support_feature(j) && \ 1323 ((j)->j_superblock->s_feature_compat & \ 1324 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \ 1325 } \ 1326 static inline void jbd2_set_feature_##name(journal_t *j) \ 1327 { \ 1328 (j)->j_superblock->s_feature_compat |= \ 1329 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1330 } \ 1331 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1332 { \ 1333 (j)->j_superblock->s_feature_compat &= \ 1334 ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1335 } 1336 1337 #define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \ 1338 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1339 { \ 1340 return (jbd2_format_support_feature(j) && \ 1341 ((j)->j_superblock->s_feature_ro_compat & \ 1342 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \ 1343 } \ 1344 static inline void jbd2_set_feature_##name(journal_t *j) \ 1345 { \ 1346 (j)->j_superblock->s_feature_ro_compat |= \ 1347 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1348 } \ 1349 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1350 { \ 1351 (j)->j_superblock->s_feature_ro_compat &= \ 1352 ~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1353 } 1354 1355 #define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \ 1356 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1357 { \ 1358 return (jbd2_format_support_feature(j) && \ 1359 ((j)->j_superblock->s_feature_incompat & \ 1360 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \ 1361 } \ 1362 static inline void jbd2_set_feature_##name(journal_t *j) \ 1363 { \ 1364 (j)->j_superblock->s_feature_incompat |= \ 1365 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1366 } \ 1367 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1368 { \ 1369 (j)->j_superblock->s_feature_incompat &= \ 1370 ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1371 } 1372 1373 JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM) 1374 1375 JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE) 1376 JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT) 1377 JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT) 1378 JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2) 1379 JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3) 1380 JBD2_FEATURE_INCOMPAT_FUNCS(fast_commit, FAST_COMMIT) 1381 1382 /* 1383 * Journal flag definitions 1384 */ 1385 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */ 1386 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */ 1387 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */ 1388 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */ 1389 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */ 1390 #define JBD2_BARRIER 0x020 /* Use IDE barriers */ 1391 #define JBD2_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file 1392 * data write error in ordered 1393 * mode */ 1394 #define JBD2_CYCLE_RECORD 0x080 /* Journal cycled record log on 1395 * clean and empty filesystem 1396 * logging area */ 1397 #define JBD2_FAST_COMMIT_ONGOING 0x100 /* Fast commit is ongoing */ 1398 #define JBD2_FULL_COMMIT_ONGOING 0x200 /* Full commit is ongoing */ 1399 #define JBD2_JOURNAL_FLUSH_DISCARD 0x0001 1400 #define JBD2_JOURNAL_FLUSH_ZEROOUT 0x0002 1401 #define JBD2_JOURNAL_FLUSH_VALID (JBD2_JOURNAL_FLUSH_DISCARD | \ 1402 JBD2_JOURNAL_FLUSH_ZEROOUT) 1403 1404 /* 1405 * Journal atomic flag definitions 1406 */ 1407 #define JBD2_CHECKPOINT_IO_ERROR 0x001 /* Detect io error while writing 1408 * buffer back to disk */ 1409 1410 /* 1411 * Function declarations for the journaling transaction and buffer 1412 * management 1413 */ 1414 1415 /* Filing buffers */ 1416 extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *); 1417 extern bool __jbd2_journal_refile_buffer(struct journal_head *); 1418 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *); 1419 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1420 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1421 static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh) 1422 { 1423 list_add_tail(&bh->b_assoc_buffers, head); 1424 } 1425 static inline void jbd2_unfile_log_bh(struct buffer_head *bh) 1426 { 1427 list_del_init(&bh->b_assoc_buffers); 1428 } 1429 1430 /* Log buffer allocation */ 1431 struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int); 1432 void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *); 1433 int jbd2_journal_next_log_block(journal_t *, unsigned long long *); 1434 int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, 1435 unsigned long *block); 1436 int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1437 void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1438 1439 /* Commit management */ 1440 extern void jbd2_journal_commit_transaction(journal_t *); 1441 1442 /* Checkpoint list management */ 1443 void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy); 1444 unsigned long jbd2_journal_shrink_checkpoint_list(journal_t *journal, unsigned long *nr_to_scan); 1445 int __jbd2_journal_remove_checkpoint(struct journal_head *); 1446 int jbd2_journal_try_remove_checkpoint(struct journal_head *jh); 1447 void jbd2_journal_destroy_checkpoint(journal_t *journal); 1448 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *); 1449 1450 1451 /* 1452 * Triggers 1453 */ 1454 1455 struct jbd2_buffer_trigger_type { 1456 /* 1457 * Fired a the moment data to write to the journal are known to be 1458 * stable - so either at the moment b_frozen_data is created or just 1459 * before a buffer is written to the journal. mapped_data is a mapped 1460 * buffer that is the frozen data for commit. 1461 */ 1462 void (*t_frozen)(struct jbd2_buffer_trigger_type *type, 1463 struct buffer_head *bh, void *mapped_data, 1464 size_t size); 1465 1466 /* 1467 * Fired during journal abort for dirty buffers that will not be 1468 * committed. 1469 */ 1470 void (*t_abort)(struct jbd2_buffer_trigger_type *type, 1471 struct buffer_head *bh); 1472 }; 1473 1474 extern void jbd2_buffer_frozen_trigger(struct journal_head *jh, 1475 void *mapped_data, 1476 struct jbd2_buffer_trigger_type *triggers); 1477 extern void jbd2_buffer_abort_trigger(struct journal_head *jh, 1478 struct jbd2_buffer_trigger_type *triggers); 1479 1480 /* Buffer IO */ 1481 extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction, 1482 struct journal_head *jh_in, 1483 struct buffer_head **bh_out, 1484 sector_t blocknr); 1485 1486 /* Transaction cache support */ 1487 extern void jbd2_journal_destroy_transaction_cache(void); 1488 extern int __init jbd2_journal_init_transaction_cache(void); 1489 extern void jbd2_journal_free_transaction(transaction_t *); 1490 1491 /* 1492 * Journal locking. 1493 * 1494 * We need to lock the journal during transaction state changes so that nobody 1495 * ever tries to take a handle on the running transaction while we are in the 1496 * middle of moving it to the commit phase. j_state_lock does this. 1497 * 1498 * Note that the locking is completely interrupt unsafe. We never touch 1499 * journal structures from interrupts. 1500 */ 1501 1502 static inline handle_t *journal_current_handle(void) 1503 { 1504 return current->journal_info; 1505 } 1506 1507 /* The journaling code user interface: 1508 * 1509 * Create and destroy handles 1510 * Register buffer modifications against the current transaction. 1511 */ 1512 1513 extern handle_t *jbd2_journal_start(journal_t *, int nblocks); 1514 extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks, 1515 int revoke_records, gfp_t gfp_mask, 1516 unsigned int type, unsigned int line_no); 1517 extern int jbd2_journal_restart(handle_t *, int nblocks); 1518 extern int jbd2__journal_restart(handle_t *, int nblocks, 1519 int revoke_records, gfp_t gfp_mask); 1520 extern int jbd2_journal_start_reserved(handle_t *handle, 1521 unsigned int type, unsigned int line_no); 1522 extern void jbd2_journal_free_reserved(handle_t *handle); 1523 extern int jbd2_journal_extend(handle_t *handle, int nblocks, 1524 int revoke_records); 1525 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *); 1526 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *); 1527 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *); 1528 void jbd2_journal_set_triggers(struct buffer_head *, 1529 struct jbd2_buffer_trigger_type *type); 1530 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *); 1531 extern int jbd2_journal_forget (handle_t *, struct buffer_head *); 1532 int jbd2_journal_invalidate_folio(journal_t *, struct folio *, 1533 size_t offset, size_t length); 1534 bool jbd2_journal_try_to_free_buffers(journal_t *journal, struct folio *folio); 1535 extern int jbd2_journal_stop(handle_t *); 1536 extern int jbd2_journal_flush(journal_t *journal, unsigned int flags); 1537 extern void jbd2_journal_lock_updates (journal_t *); 1538 extern void jbd2_journal_unlock_updates (journal_t *); 1539 1540 void jbd2_journal_wait_updates(journal_t *); 1541 1542 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev, 1543 struct block_device *fs_dev, 1544 unsigned long long start, int len, int bsize); 1545 extern journal_t * jbd2_journal_init_inode (struct inode *); 1546 extern int jbd2_journal_update_format (journal_t *); 1547 extern int jbd2_journal_check_used_features 1548 (journal_t *, unsigned long, unsigned long, unsigned long); 1549 extern int jbd2_journal_check_available_features 1550 (journal_t *, unsigned long, unsigned long, unsigned long); 1551 extern int jbd2_journal_set_features 1552 (journal_t *, unsigned long, unsigned long, unsigned long); 1553 extern void jbd2_journal_clear_features 1554 (journal_t *, unsigned long, unsigned long, unsigned long); 1555 extern int jbd2_journal_load (journal_t *journal); 1556 extern int jbd2_journal_destroy (journal_t *); 1557 extern int jbd2_journal_recover (journal_t *journal); 1558 extern int jbd2_journal_wipe (journal_t *, int); 1559 extern int jbd2_journal_skip_recovery (journal_t *); 1560 extern void jbd2_journal_update_sb_errno(journal_t *); 1561 extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t, 1562 unsigned long, blk_opf_t); 1563 extern void jbd2_journal_abort (journal_t *, int); 1564 extern int jbd2_journal_errno (journal_t *); 1565 extern void jbd2_journal_ack_err (journal_t *); 1566 extern int jbd2_journal_clear_err (journal_t *); 1567 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *); 1568 extern int jbd2_journal_force_commit(journal_t *); 1569 extern int jbd2_journal_force_commit_nested(journal_t *); 1570 extern int jbd2_journal_inode_ranged_write(handle_t *handle, 1571 struct jbd2_inode *inode, loff_t start_byte, 1572 loff_t length); 1573 extern int jbd2_journal_inode_ranged_wait(handle_t *handle, 1574 struct jbd2_inode *inode, loff_t start_byte, 1575 loff_t length); 1576 extern int jbd2_journal_finish_inode_data_buffers( 1577 struct jbd2_inode *jinode); 1578 extern int jbd2_journal_begin_ordered_truncate(journal_t *journal, 1579 struct jbd2_inode *inode, loff_t new_size); 1580 extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode); 1581 extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode); 1582 1583 /* 1584 * journal_head management 1585 */ 1586 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh); 1587 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh); 1588 void jbd2_journal_put_journal_head(struct journal_head *jh); 1589 1590 /* 1591 * handle management 1592 */ 1593 extern struct kmem_cache *jbd2_handle_cache; 1594 1595 static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags) 1596 { 1597 return kmem_cache_zalloc(jbd2_handle_cache, gfp_flags); 1598 } 1599 1600 static inline void jbd2_free_handle(handle_t *handle) 1601 { 1602 kmem_cache_free(jbd2_handle_cache, handle); 1603 } 1604 1605 /* 1606 * jbd2_inode management (optional, for those file systems that want to use 1607 * dynamically allocated jbd2_inode structures) 1608 */ 1609 extern struct kmem_cache *jbd2_inode_cache; 1610 1611 static inline struct jbd2_inode *jbd2_alloc_inode(gfp_t gfp_flags) 1612 { 1613 return kmem_cache_alloc(jbd2_inode_cache, gfp_flags); 1614 } 1615 1616 static inline void jbd2_free_inode(struct jbd2_inode *jinode) 1617 { 1618 kmem_cache_free(jbd2_inode_cache, jinode); 1619 } 1620 1621 /* Primary revoke support */ 1622 #define JOURNAL_REVOKE_DEFAULT_HASH 256 1623 extern int jbd2_journal_init_revoke(journal_t *, int); 1624 extern void jbd2_journal_destroy_revoke_record_cache(void); 1625 extern void jbd2_journal_destroy_revoke_table_cache(void); 1626 extern int __init jbd2_journal_init_revoke_record_cache(void); 1627 extern int __init jbd2_journal_init_revoke_table_cache(void); 1628 1629 extern void jbd2_journal_destroy_revoke(journal_t *); 1630 extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *); 1631 extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *); 1632 extern void jbd2_journal_write_revoke_records(transaction_t *transaction, 1633 struct list_head *log_bufs); 1634 1635 /* Recovery revoke support */ 1636 extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t); 1637 extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t); 1638 extern void jbd2_journal_clear_revoke(journal_t *); 1639 extern void jbd2_journal_switch_revoke_table(journal_t *journal); 1640 extern void jbd2_clear_buffer_revoked_flags(journal_t *journal); 1641 1642 /* 1643 * The log thread user interface: 1644 * 1645 * Request space in the current transaction, and force transaction commit 1646 * transitions on demand. 1647 */ 1648 1649 int jbd2_log_start_commit(journal_t *journal, tid_t tid); 1650 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid); 1651 int jbd2_log_wait_commit(journal_t *journal, tid_t tid); 1652 int jbd2_transaction_committed(journal_t *journal, tid_t tid); 1653 int jbd2_complete_transaction(journal_t *journal, tid_t tid); 1654 int jbd2_log_do_checkpoint(journal_t *journal); 1655 int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid); 1656 1657 void __jbd2_log_wait_for_space(journal_t *journal); 1658 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *); 1659 extern int jbd2_cleanup_journal_tail(journal_t *); 1660 1661 /* Fast commit related APIs */ 1662 int jbd2_fc_begin_commit(journal_t *journal, tid_t tid); 1663 int jbd2_fc_end_commit(journal_t *journal); 1664 int jbd2_fc_end_commit_fallback(journal_t *journal); 1665 int jbd2_fc_get_buf(journal_t *journal, struct buffer_head **bh_out); 1666 int jbd2_submit_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1667 int jbd2_wait_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1668 int jbd2_fc_wait_bufs(journal_t *journal, int num_blks); 1669 int jbd2_fc_release_bufs(journal_t *journal); 1670 1671 static inline int jbd2_journal_get_max_txn_bufs(journal_t *journal) 1672 { 1673 return (journal->j_total_len - journal->j_fc_wbufsize) / 4; 1674 } 1675 1676 /* 1677 * is_journal_abort 1678 * 1679 * Simple test wrapper function to test the JBD2_ABORT state flag. This 1680 * bit, when set, indicates that we have had a fatal error somewhere, 1681 * either inside the journaling layer or indicated to us by the client 1682 * (eg. ext3), and that we and should not commit any further 1683 * transactions. 1684 */ 1685 1686 static inline int is_journal_aborted(journal_t *journal) 1687 { 1688 return journal->j_flags & JBD2_ABORT; 1689 } 1690 1691 static inline int is_handle_aborted(handle_t *handle) 1692 { 1693 if (handle->h_aborted || !handle->h_transaction) 1694 return 1; 1695 return is_journal_aborted(handle->h_transaction->t_journal); 1696 } 1697 1698 static inline void jbd2_journal_abort_handle(handle_t *handle) 1699 { 1700 handle->h_aborted = 1; 1701 } 1702 1703 #endif /* __KERNEL__ */ 1704 1705 /* Comparison functions for transaction IDs: perform comparisons using 1706 * modulo arithmetic so that they work over sequence number wraps. */ 1707 1708 static inline int tid_gt(tid_t x, tid_t y) 1709 { 1710 int difference = (x - y); 1711 return (difference > 0); 1712 } 1713 1714 static inline int tid_geq(tid_t x, tid_t y) 1715 { 1716 int difference = (x - y); 1717 return (difference >= 0); 1718 } 1719 1720 extern int jbd2_journal_blocks_per_page(struct inode *inode); 1721 extern size_t journal_tag_bytes(journal_t *journal); 1722 1723 static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j) 1724 { 1725 return jbd2_has_feature_csum2(j) || jbd2_has_feature_csum3(j); 1726 } 1727 1728 static inline int jbd2_journal_has_csum_v2or3(journal_t *journal) 1729 { 1730 WARN_ON_ONCE(jbd2_journal_has_csum_v2or3_feature(journal) && 1731 journal->j_chksum_driver == NULL); 1732 1733 return journal->j_chksum_driver != NULL; 1734 } 1735 1736 static inline int jbd2_journal_get_num_fc_blks(journal_superblock_t *jsb) 1737 { 1738 int num_fc_blocks = be32_to_cpu(jsb->s_num_fc_blks); 1739 1740 return num_fc_blocks ? num_fc_blocks : JBD2_DEFAULT_FAST_COMMIT_BLOCKS; 1741 } 1742 1743 /* 1744 * Return number of free blocks in the log. Must be called under j_state_lock. 1745 */ 1746 static inline unsigned long jbd2_log_space_left(journal_t *journal) 1747 { 1748 /* Allow for rounding errors */ 1749 long free = journal->j_free - 32; 1750 1751 if (journal->j_committing_transaction) { 1752 free -= atomic_read(&journal-> 1753 j_committing_transaction->t_outstanding_credits); 1754 } 1755 return max_t(long, free, 0); 1756 } 1757 1758 /* 1759 * Definitions which augment the buffer_head layer 1760 */ 1761 1762 /* journaling buffer types */ 1763 #define BJ_None 0 /* Not journaled */ 1764 #define BJ_Metadata 1 /* Normal journaled metadata */ 1765 #define BJ_Forget 2 /* Buffer superseded by this transaction */ 1766 #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */ 1767 #define BJ_Reserved 4 /* Buffer is reserved for access by journal */ 1768 #define BJ_Types 5 1769 1770 /* JBD uses a CRC32 checksum */ 1771 #define JBD_MAX_CHECKSUM_SIZE 4 1772 1773 static inline u32 jbd2_chksum(journal_t *journal, u32 crc, 1774 const void *address, unsigned int length) 1775 { 1776 struct { 1777 struct shash_desc shash; 1778 char ctx[JBD_MAX_CHECKSUM_SIZE]; 1779 } desc; 1780 int err; 1781 1782 BUG_ON(crypto_shash_descsize(journal->j_chksum_driver) > 1783 JBD_MAX_CHECKSUM_SIZE); 1784 1785 desc.shash.tfm = journal->j_chksum_driver; 1786 *(u32 *)desc.ctx = crc; 1787 1788 err = crypto_shash_update(&desc.shash, address, length); 1789 BUG_ON(err); 1790 1791 return *(u32 *)desc.ctx; 1792 } 1793 1794 /* Return most recent uncommitted transaction */ 1795 static inline tid_t jbd2_get_latest_transaction(journal_t *journal) 1796 { 1797 tid_t tid; 1798 1799 read_lock(&journal->j_state_lock); 1800 tid = journal->j_commit_request; 1801 if (journal->j_running_transaction) 1802 tid = journal->j_running_transaction->t_tid; 1803 read_unlock(&journal->j_state_lock); 1804 return tid; 1805 } 1806 1807 static inline int jbd2_handle_buffer_credits(handle_t *handle) 1808 { 1809 journal_t *journal; 1810 1811 if (!handle->h_reserved) 1812 journal = handle->h_transaction->t_journal; 1813 else 1814 journal = handle->h_journal; 1815 1816 return handle->h_total_credits - 1817 DIV_ROUND_UP(handle->h_revoke_credits_requested, 1818 journal->j_revoke_records_per_block); 1819 } 1820 1821 #ifdef __KERNEL__ 1822 1823 #define buffer_trace_init(bh) do {} while (0) 1824 #define print_buffer_fields(bh) do {} while (0) 1825 #define print_buffer_trace(bh) do {} while (0) 1826 #define BUFFER_TRACE(bh, info) do {} while (0) 1827 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0) 1828 #define JBUFFER_TRACE(jh, info) do {} while (0) 1829 1830 #endif /* __KERNEL__ */ 1831 1832 #define EFSBADCRC EBADMSG /* Bad CRC detected */ 1833 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ 1834 1835 #endif /* _LINUX_JBD2_H */ 1836