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 * Longest time some handle had to wait for running transaction 635 */ 636 unsigned long t_max_wait; 637 638 /* 639 * When transaction started 640 */ 641 unsigned long t_start; 642 643 /* 644 * When commit was requested [j_state_lock] 645 */ 646 unsigned long t_requested; 647 648 /* 649 * Checkpointing stats [j_list_lock] 650 */ 651 struct transaction_chp_stats_s t_chp_stats; 652 653 /* 654 * Number of outstanding updates running on this transaction 655 * [none] 656 */ 657 atomic_t t_updates; 658 659 /* 660 * Number of blocks reserved for this transaction in the journal. 661 * This is including all credits reserved when starting transaction 662 * handles as well as all journal descriptor blocks needed for this 663 * transaction. [none] 664 */ 665 atomic_t t_outstanding_credits; 666 667 /* 668 * Number of revoke records for this transaction added by already 669 * stopped handles. [none] 670 */ 671 atomic_t t_outstanding_revokes; 672 673 /* 674 * How many handles used this transaction? [none] 675 */ 676 atomic_t t_handle_count; 677 678 /* 679 * Forward and backward links for the circular list of all transactions 680 * awaiting checkpoint. [j_list_lock] 681 */ 682 transaction_t *t_cpnext, *t_cpprev; 683 684 /* 685 * When will the transaction expire (become due for commit), in jiffies? 686 * [no locking] 687 */ 688 unsigned long t_expires; 689 690 /* 691 * When this transaction started, in nanoseconds [no locking] 692 */ 693 ktime_t t_start_time; 694 695 /* 696 * This transaction is being forced and some process is 697 * waiting for it to finish. 698 */ 699 unsigned int t_synchronous_commit:1; 700 701 /* Disk flush needs to be sent to fs partition [no locking] */ 702 int t_need_data_flush; 703 704 /* 705 * For use by the filesystem to store fs-specific data 706 * structures associated with the transaction 707 */ 708 struct list_head t_private_list; 709 }; 710 711 struct transaction_run_stats_s { 712 unsigned long rs_wait; 713 unsigned long rs_request_delay; 714 unsigned long rs_running; 715 unsigned long rs_locked; 716 unsigned long rs_flushing; 717 unsigned long rs_logging; 718 719 __u32 rs_handle_count; 720 __u32 rs_blocks; 721 __u32 rs_blocks_logged; 722 }; 723 724 struct transaction_stats_s { 725 unsigned long ts_tid; 726 unsigned long ts_requested; 727 struct transaction_run_stats_s run; 728 }; 729 730 static inline unsigned long 731 jbd2_time_diff(unsigned long start, unsigned long end) 732 { 733 if (end >= start) 734 return end - start; 735 736 return end + (MAX_JIFFY_OFFSET - start); 737 } 738 739 #define JBD2_NR_BATCH 64 740 741 enum passtype {PASS_SCAN, PASS_REVOKE, PASS_REPLAY}; 742 743 #define JBD2_FC_REPLAY_STOP 0 744 #define JBD2_FC_REPLAY_CONTINUE 1 745 746 /** 747 * struct journal_s - The journal_s type is the concrete type associated with 748 * journal_t. 749 */ 750 struct journal_s 751 { 752 /** 753 * @j_flags: General journaling state flags [j_state_lock, 754 * no lock for quick racy checks] 755 */ 756 unsigned long j_flags; 757 758 /** 759 * @j_atomic_flags: Atomic journaling state flags. 760 */ 761 unsigned long j_atomic_flags; 762 763 /** 764 * @j_errno: 765 * 766 * Is there an outstanding uncleared error on the journal (from a prior 767 * abort)? [j_state_lock] 768 */ 769 int j_errno; 770 771 /** 772 * @j_abort_mutex: Lock the whole aborting procedure. 773 */ 774 struct mutex j_abort_mutex; 775 776 /** 777 * @j_sb_buffer: The first part of the superblock buffer. 778 */ 779 struct buffer_head *j_sb_buffer; 780 781 /** 782 * @j_superblock: The second part of the superblock buffer. 783 */ 784 journal_superblock_t *j_superblock; 785 786 /** 787 * @j_state_lock: Protect the various scalars in the journal. 788 */ 789 rwlock_t j_state_lock; 790 791 /** 792 * @j_barrier_count: 793 * 794 * Number of processes waiting to create a barrier lock [j_state_lock, 795 * no lock for quick racy checks] 796 */ 797 int j_barrier_count; 798 799 /** 800 * @j_barrier: The barrier lock itself. 801 */ 802 struct mutex j_barrier; 803 804 /** 805 * @j_running_transaction: 806 * 807 * Transactions: The current running transaction... 808 * [j_state_lock, no lock for quick racy checks] [caller holding 809 * open handle] 810 */ 811 transaction_t *j_running_transaction; 812 813 /** 814 * @j_committing_transaction: 815 * 816 * the transaction we are pushing to disk 817 * [j_state_lock] [caller holding open handle] 818 */ 819 transaction_t *j_committing_transaction; 820 821 /** 822 * @j_checkpoint_transactions: 823 * 824 * ... and a linked circular list of all transactions waiting for 825 * checkpointing. [j_list_lock] 826 */ 827 transaction_t *j_checkpoint_transactions; 828 829 /** 830 * @j_wait_transaction_locked: 831 * 832 * Wait queue for waiting for a locked transaction to start committing, 833 * or for a barrier lock to be released. 834 */ 835 wait_queue_head_t j_wait_transaction_locked; 836 837 /** 838 * @j_wait_done_commit: Wait queue for waiting for commit to complete. 839 */ 840 wait_queue_head_t j_wait_done_commit; 841 842 /** 843 * @j_wait_commit: Wait queue to trigger commit. 844 */ 845 wait_queue_head_t j_wait_commit; 846 847 /** 848 * @j_wait_updates: Wait queue to wait for updates to complete. 849 */ 850 wait_queue_head_t j_wait_updates; 851 852 /** 853 * @j_wait_reserved: 854 * 855 * Wait queue to wait for reserved buffer credits to drop. 856 */ 857 wait_queue_head_t j_wait_reserved; 858 859 /** 860 * @j_fc_wait: 861 * 862 * Wait queue to wait for completion of async fast commits. 863 */ 864 wait_queue_head_t j_fc_wait; 865 866 /** 867 * @j_checkpoint_mutex: 868 * 869 * Semaphore for locking against concurrent checkpoints. 870 */ 871 struct mutex j_checkpoint_mutex; 872 873 /** 874 * @j_chkpt_bhs: 875 * 876 * List of buffer heads used by the checkpoint routine. This 877 * was moved from jbd2_log_do_checkpoint() to reduce stack 878 * usage. Access to this array is controlled by the 879 * @j_checkpoint_mutex. [j_checkpoint_mutex] 880 */ 881 struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH]; 882 883 /** 884 * @j_shrinker: 885 * 886 * Journal head shrinker, reclaim buffer's journal head which 887 * has been written back. 888 */ 889 struct shrinker *j_shrinker; 890 891 /** 892 * @j_checkpoint_jh_count: 893 * 894 * Number of journal buffers on the checkpoint list. [j_list_lock] 895 */ 896 struct percpu_counter j_checkpoint_jh_count; 897 898 /** 899 * @j_shrink_transaction: 900 * 901 * Record next transaction will shrink on the checkpoint list. 902 * [j_list_lock] 903 */ 904 transaction_t *j_shrink_transaction; 905 906 /** 907 * @j_head: 908 * 909 * Journal head: identifies the first unused block in the journal. 910 * [j_state_lock] 911 */ 912 unsigned long j_head; 913 914 /** 915 * @j_tail: 916 * 917 * Journal tail: identifies the oldest still-used block in the journal. 918 * [j_state_lock] 919 */ 920 unsigned long j_tail; 921 922 /** 923 * @j_free: 924 * 925 * Journal free: how many free blocks are there in the journal? 926 * [j_state_lock] 927 */ 928 unsigned long j_free; 929 930 /** 931 * @j_first: 932 * 933 * The block number of the first usable block in the journal 934 * [j_state_lock]. 935 */ 936 unsigned long j_first; 937 938 /** 939 * @j_last: 940 * 941 * The block number one beyond the last usable block in the journal 942 * [j_state_lock]. 943 */ 944 unsigned long j_last; 945 946 /** 947 * @j_fc_first: 948 * 949 * The block number of the first fast commit block in the journal 950 * [j_state_lock]. 951 */ 952 unsigned long j_fc_first; 953 954 /** 955 * @j_fc_off: 956 * 957 * Number of fast commit blocks currently allocated. Accessed only 958 * during fast commit. Currently only process can do fast commit, so 959 * this field is not protected by any lock. 960 */ 961 unsigned long j_fc_off; 962 963 /** 964 * @j_fc_last: 965 * 966 * The block number one beyond the last fast commit block in the journal 967 * [j_state_lock]. 968 */ 969 unsigned long j_fc_last; 970 971 /** 972 * @j_dev: Device where we store the journal. 973 */ 974 struct block_device *j_dev; 975 976 /** 977 * @j_blocksize: Block size for the location where we store the journal. 978 */ 979 int j_blocksize; 980 981 /** 982 * @j_blk_offset: 983 * 984 * Starting block offset into the device where we store the journal. 985 */ 986 unsigned long long j_blk_offset; 987 988 /** 989 * @j_devname: Journal device name. 990 */ 991 char j_devname[BDEVNAME_SIZE+24]; 992 993 /** 994 * @j_fs_dev: 995 * 996 * Device which holds the client fs. For internal journal this will be 997 * equal to j_dev. 998 */ 999 struct block_device *j_fs_dev; 1000 1001 /** 1002 * @j_total_len: Total maximum capacity of the journal region on disk. 1003 */ 1004 unsigned int j_total_len; 1005 1006 /** 1007 * @j_reserved_credits: 1008 * 1009 * Number of buffers reserved from the running transaction. 1010 */ 1011 atomic_t j_reserved_credits; 1012 1013 /** 1014 * @j_list_lock: Protects the buffer lists and internal buffer state. 1015 */ 1016 spinlock_t j_list_lock; 1017 1018 /** 1019 * @j_inode: 1020 * 1021 * Optional inode where we store the journal. If present, all 1022 * journal block numbers are mapped into this inode via bmap(). 1023 */ 1024 struct inode *j_inode; 1025 1026 /** 1027 * @j_tail_sequence: 1028 * 1029 * Sequence number of the oldest transaction in the log [j_state_lock] 1030 */ 1031 tid_t j_tail_sequence; 1032 1033 /** 1034 * @j_transaction_sequence: 1035 * 1036 * Sequence number of the next transaction to grant [j_state_lock] 1037 */ 1038 tid_t j_transaction_sequence; 1039 1040 /** 1041 * @j_commit_sequence: 1042 * 1043 * Sequence number of the most recently committed transaction 1044 * [j_state_lock, no lock for quick racy checks] 1045 */ 1046 tid_t j_commit_sequence; 1047 1048 /** 1049 * @j_commit_request: 1050 * 1051 * Sequence number of the most recent transaction wanting commit 1052 * [j_state_lock, no lock for quick racy checks] 1053 */ 1054 tid_t j_commit_request; 1055 1056 /** 1057 * @j_uuid: 1058 * 1059 * Journal uuid: identifies the object (filesystem, LVM volume etc) 1060 * backed by this journal. This will eventually be replaced by an array 1061 * of uuids, allowing us to index multiple devices within a single 1062 * journal and to perform atomic updates across them. 1063 */ 1064 __u8 j_uuid[16]; 1065 1066 /** 1067 * @j_task: Pointer to the current commit thread for this journal. 1068 */ 1069 struct task_struct *j_task; 1070 1071 /** 1072 * @j_max_transaction_buffers: 1073 * 1074 * Maximum number of metadata buffers to allow in a single compound 1075 * commit transaction. 1076 */ 1077 int j_max_transaction_buffers; 1078 1079 /** 1080 * @j_revoke_records_per_block: 1081 * 1082 * Number of revoke records that fit in one descriptor block. 1083 */ 1084 int j_revoke_records_per_block; 1085 1086 /** 1087 * @j_commit_interval: 1088 * 1089 * What is the maximum transaction lifetime before we begin a commit? 1090 */ 1091 unsigned long j_commit_interval; 1092 1093 /** 1094 * @j_commit_timer: The timer used to wakeup the commit thread. 1095 */ 1096 struct timer_list j_commit_timer; 1097 1098 /** 1099 * @j_revoke_lock: Protect the revoke table. 1100 */ 1101 spinlock_t j_revoke_lock; 1102 1103 /** 1104 * @j_revoke: 1105 * 1106 * The revoke table - maintains the list of revoked blocks in the 1107 * current transaction. 1108 */ 1109 struct jbd2_revoke_table_s *j_revoke; 1110 1111 /** 1112 * @j_revoke_table: Alternate revoke tables for j_revoke. 1113 */ 1114 struct jbd2_revoke_table_s *j_revoke_table[2]; 1115 1116 /** 1117 * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction. 1118 */ 1119 struct buffer_head **j_wbuf; 1120 1121 /** 1122 * @j_fc_wbuf: Array of fast commit bhs for fast commit. Accessed only 1123 * during a fast commit. Currently only process can do fast commit, so 1124 * this field is not protected by any lock. 1125 */ 1126 struct buffer_head **j_fc_wbuf; 1127 1128 /** 1129 * @j_wbufsize: 1130 * 1131 * Size of @j_wbuf array. 1132 */ 1133 int j_wbufsize; 1134 1135 /** 1136 * @j_fc_wbufsize: 1137 * 1138 * Size of @j_fc_wbuf array. 1139 */ 1140 int j_fc_wbufsize; 1141 1142 /** 1143 * @j_last_sync_writer: 1144 * 1145 * The pid of the last person to run a synchronous operation 1146 * through the journal. 1147 */ 1148 pid_t j_last_sync_writer; 1149 1150 /** 1151 * @j_average_commit_time: 1152 * 1153 * The average amount of time in nanoseconds it takes to commit a 1154 * transaction to disk. [j_state_lock] 1155 */ 1156 u64 j_average_commit_time; 1157 1158 /** 1159 * @j_min_batch_time: 1160 * 1161 * Minimum time that we should wait for additional filesystem operations 1162 * to get batched into a synchronous handle in microseconds. 1163 */ 1164 u32 j_min_batch_time; 1165 1166 /** 1167 * @j_max_batch_time: 1168 * 1169 * Maximum time that we should wait for additional filesystem operations 1170 * to get batched into a synchronous handle in microseconds. 1171 */ 1172 u32 j_max_batch_time; 1173 1174 /** 1175 * @j_commit_callback: 1176 * 1177 * This function is called when a transaction is closed. 1178 */ 1179 void (*j_commit_callback)(journal_t *, 1180 transaction_t *); 1181 1182 /** 1183 * @j_submit_inode_data_buffers: 1184 * 1185 * This function is called for all inodes associated with the 1186 * committing transaction marked with JI_WRITE_DATA flag 1187 * before we start to write out the transaction to the journal. 1188 */ 1189 int (*j_submit_inode_data_buffers) 1190 (struct jbd2_inode *); 1191 1192 /** 1193 * @j_finish_inode_data_buffers: 1194 * 1195 * This function is called for all inodes associated with the 1196 * committing transaction marked with JI_WAIT_DATA flag 1197 * after we have written the transaction to the journal 1198 * but before we write out the commit block. 1199 */ 1200 int (*j_finish_inode_data_buffers) 1201 (struct jbd2_inode *); 1202 1203 /* 1204 * Journal statistics 1205 */ 1206 1207 /** 1208 * @j_history_lock: Protect the transactions statistics history. 1209 */ 1210 spinlock_t j_history_lock; 1211 1212 /** 1213 * @j_proc_entry: procfs entry for the jbd statistics directory. 1214 */ 1215 struct proc_dir_entry *j_proc_entry; 1216 1217 /** 1218 * @j_stats: Overall statistics. 1219 */ 1220 struct transaction_stats_s j_stats; 1221 1222 /** 1223 * @j_failed_commit: Failed journal commit ID. 1224 */ 1225 unsigned int j_failed_commit; 1226 1227 /** 1228 * @j_private: 1229 * 1230 * An opaque pointer to fs-private information. ext3 puts its 1231 * superblock pointer here. 1232 */ 1233 void *j_private; 1234 1235 /** 1236 * @j_chksum_driver: 1237 * 1238 * Reference to checksum algorithm driver via cryptoapi. 1239 */ 1240 struct crypto_shash *j_chksum_driver; 1241 1242 /** 1243 * @j_csum_seed: 1244 * 1245 * Precomputed journal UUID checksum for seeding other checksums. 1246 */ 1247 __u32 j_csum_seed; 1248 1249 #ifdef CONFIG_DEBUG_LOCK_ALLOC 1250 /** 1251 * @j_trans_commit_map: 1252 * 1253 * Lockdep entity to track transaction commit dependencies. Handles 1254 * hold this "lock" for read, when we wait for commit, we acquire the 1255 * "lock" for writing. This matches the properties of jbd2 journalling 1256 * where the running transaction has to wait for all handles to be 1257 * dropped to commit that transaction and also acquiring a handle may 1258 * require transaction commit to finish. 1259 */ 1260 struct lockdep_map j_trans_commit_map; 1261 #endif 1262 1263 /** 1264 * @j_fc_cleanup_callback: 1265 * 1266 * Clean-up after fast commit or full commit. JBD2 calls this function 1267 * after every commit operation. 1268 */ 1269 void (*j_fc_cleanup_callback)(struct journal_s *journal, int full, tid_t tid); 1270 1271 /** 1272 * @j_fc_replay_callback: 1273 * 1274 * File-system specific function that performs replay of a fast 1275 * commit. JBD2 calls this function for each fast commit block found in 1276 * the journal. This function should return JBD2_FC_REPLAY_CONTINUE 1277 * to indicate that the block was processed correctly and more fast 1278 * commit replay should continue. Return value of JBD2_FC_REPLAY_STOP 1279 * indicates the end of replay (no more blocks remaining). A negative 1280 * return value indicates error. 1281 */ 1282 int (*j_fc_replay_callback)(struct journal_s *journal, 1283 struct buffer_head *bh, 1284 enum passtype pass, int off, 1285 tid_t expected_commit_id); 1286 1287 /** 1288 * @j_bmap: 1289 * 1290 * Bmap function that should be used instead of the generic 1291 * VFS bmap function. 1292 */ 1293 int (*j_bmap)(struct journal_s *journal, sector_t *block); 1294 }; 1295 1296 #define jbd2_might_wait_for_commit(j) \ 1297 do { \ 1298 rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \ 1299 rwsem_release(&j->j_trans_commit_map, _THIS_IP_); \ 1300 } while (0) 1301 1302 /* 1303 * We can support any known requested features iff the 1304 * superblock is not in version 1. Otherwise we fail to support any 1305 * extended sb features. 1306 */ 1307 static inline bool jbd2_format_support_feature(journal_t *j) 1308 { 1309 return j->j_superblock->s_header.h_blocktype != 1310 cpu_to_be32(JBD2_SUPERBLOCK_V1); 1311 } 1312 1313 /* journal feature predicate functions */ 1314 #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \ 1315 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1316 { \ 1317 return (jbd2_format_support_feature(j) && \ 1318 ((j)->j_superblock->s_feature_compat & \ 1319 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \ 1320 } \ 1321 static inline void jbd2_set_feature_##name(journal_t *j) \ 1322 { \ 1323 (j)->j_superblock->s_feature_compat |= \ 1324 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1325 } \ 1326 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1327 { \ 1328 (j)->j_superblock->s_feature_compat &= \ 1329 ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1330 } 1331 1332 #define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \ 1333 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1334 { \ 1335 return (jbd2_format_support_feature(j) && \ 1336 ((j)->j_superblock->s_feature_ro_compat & \ 1337 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \ 1338 } \ 1339 static inline void jbd2_set_feature_##name(journal_t *j) \ 1340 { \ 1341 (j)->j_superblock->s_feature_ro_compat |= \ 1342 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1343 } \ 1344 static inline void jbd2_clear_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 1350 #define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \ 1351 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1352 { \ 1353 return (jbd2_format_support_feature(j) && \ 1354 ((j)->j_superblock->s_feature_incompat & \ 1355 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \ 1356 } \ 1357 static inline void jbd2_set_feature_##name(journal_t *j) \ 1358 { \ 1359 (j)->j_superblock->s_feature_incompat |= \ 1360 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1361 } \ 1362 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1363 { \ 1364 (j)->j_superblock->s_feature_incompat &= \ 1365 ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1366 } 1367 1368 JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM) 1369 1370 JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE) 1371 JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT) 1372 JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT) 1373 JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2) 1374 JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3) 1375 JBD2_FEATURE_INCOMPAT_FUNCS(fast_commit, FAST_COMMIT) 1376 1377 /* 1378 * Journal flag definitions 1379 */ 1380 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */ 1381 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */ 1382 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */ 1383 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */ 1384 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */ 1385 #define JBD2_BARRIER 0x020 /* Use IDE barriers */ 1386 #define JBD2_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file 1387 * data write error in ordered 1388 * mode */ 1389 #define JBD2_CYCLE_RECORD 0x080 /* Journal cycled record log on 1390 * clean and empty filesystem 1391 * logging area */ 1392 #define JBD2_FAST_COMMIT_ONGOING 0x100 /* Fast commit is ongoing */ 1393 #define JBD2_FULL_COMMIT_ONGOING 0x200 /* Full commit is ongoing */ 1394 #define JBD2_JOURNAL_FLUSH_DISCARD 0x0001 1395 #define JBD2_JOURNAL_FLUSH_ZEROOUT 0x0002 1396 #define JBD2_JOURNAL_FLUSH_VALID (JBD2_JOURNAL_FLUSH_DISCARD | \ 1397 JBD2_JOURNAL_FLUSH_ZEROOUT) 1398 1399 /* 1400 * Journal atomic flag definitions 1401 */ 1402 #define JBD2_CHECKPOINT_IO_ERROR 0x001 /* Detect io error while writing 1403 * buffer back to disk */ 1404 1405 /* 1406 * Function declarations for the journaling transaction and buffer 1407 * management 1408 */ 1409 1410 /* Filing buffers */ 1411 extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *); 1412 extern bool __jbd2_journal_refile_buffer(struct journal_head *); 1413 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *); 1414 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1415 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1416 static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh) 1417 { 1418 list_add_tail(&bh->b_assoc_buffers, head); 1419 } 1420 static inline void jbd2_unfile_log_bh(struct buffer_head *bh) 1421 { 1422 list_del_init(&bh->b_assoc_buffers); 1423 } 1424 1425 /* Log buffer allocation */ 1426 struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int); 1427 void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *); 1428 int jbd2_journal_next_log_block(journal_t *, unsigned long long *); 1429 int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, 1430 unsigned long *block); 1431 int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1432 void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1433 1434 /* Commit management */ 1435 extern void jbd2_journal_commit_transaction(journal_t *); 1436 1437 /* Checkpoint list management */ 1438 void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy); 1439 unsigned long jbd2_journal_shrink_checkpoint_list(journal_t *journal, unsigned long *nr_to_scan); 1440 int __jbd2_journal_remove_checkpoint(struct journal_head *); 1441 int jbd2_journal_try_remove_checkpoint(struct journal_head *jh); 1442 void jbd2_journal_destroy_checkpoint(journal_t *journal); 1443 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *); 1444 1445 1446 /* 1447 * Triggers 1448 */ 1449 1450 struct jbd2_buffer_trigger_type { 1451 /* 1452 * Fired a the moment data to write to the journal are known to be 1453 * stable - so either at the moment b_frozen_data is created or just 1454 * before a buffer is written to the journal. mapped_data is a mapped 1455 * buffer that is the frozen data for commit. 1456 */ 1457 void (*t_frozen)(struct jbd2_buffer_trigger_type *type, 1458 struct buffer_head *bh, void *mapped_data, 1459 size_t size); 1460 1461 /* 1462 * Fired during journal abort for dirty buffers that will not be 1463 * committed. 1464 */ 1465 void (*t_abort)(struct jbd2_buffer_trigger_type *type, 1466 struct buffer_head *bh); 1467 }; 1468 1469 extern void jbd2_buffer_frozen_trigger(struct journal_head *jh, 1470 void *mapped_data, 1471 struct jbd2_buffer_trigger_type *triggers); 1472 extern void jbd2_buffer_abort_trigger(struct journal_head *jh, 1473 struct jbd2_buffer_trigger_type *triggers); 1474 1475 /* Buffer IO */ 1476 extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction, 1477 struct journal_head *jh_in, 1478 struct buffer_head **bh_out, 1479 sector_t blocknr); 1480 1481 /* Transaction cache support */ 1482 extern void jbd2_journal_destroy_transaction_cache(void); 1483 extern int __init jbd2_journal_init_transaction_cache(void); 1484 extern void jbd2_journal_free_transaction(transaction_t *); 1485 1486 /* 1487 * Journal locking. 1488 * 1489 * We need to lock the journal during transaction state changes so that nobody 1490 * ever tries to take a handle on the running transaction while we are in the 1491 * middle of moving it to the commit phase. j_state_lock does this. 1492 * 1493 * Note that the locking is completely interrupt unsafe. We never touch 1494 * journal structures from interrupts. 1495 */ 1496 1497 static inline handle_t *journal_current_handle(void) 1498 { 1499 return current->journal_info; 1500 } 1501 1502 /* The journaling code user interface: 1503 * 1504 * Create and destroy handles 1505 * Register buffer modifications against the current transaction. 1506 */ 1507 1508 extern handle_t *jbd2_journal_start(journal_t *, int nblocks); 1509 extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks, 1510 int revoke_records, gfp_t gfp_mask, 1511 unsigned int type, unsigned int line_no); 1512 extern int jbd2_journal_restart(handle_t *, int nblocks); 1513 extern int jbd2__journal_restart(handle_t *, int nblocks, 1514 int revoke_records, gfp_t gfp_mask); 1515 extern int jbd2_journal_start_reserved(handle_t *handle, 1516 unsigned int type, unsigned int line_no); 1517 extern void jbd2_journal_free_reserved(handle_t *handle); 1518 extern int jbd2_journal_extend(handle_t *handle, int nblocks, 1519 int revoke_records); 1520 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *); 1521 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *); 1522 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *); 1523 void jbd2_journal_set_triggers(struct buffer_head *, 1524 struct jbd2_buffer_trigger_type *type); 1525 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *); 1526 extern int jbd2_journal_forget (handle_t *, struct buffer_head *); 1527 int jbd2_journal_invalidate_folio(journal_t *, struct folio *, 1528 size_t offset, size_t length); 1529 bool jbd2_journal_try_to_free_buffers(journal_t *journal, struct folio *folio); 1530 extern int jbd2_journal_stop(handle_t *); 1531 extern int jbd2_journal_flush(journal_t *journal, unsigned int flags); 1532 extern void jbd2_journal_lock_updates (journal_t *); 1533 extern void jbd2_journal_unlock_updates (journal_t *); 1534 1535 void jbd2_journal_wait_updates(journal_t *); 1536 1537 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev, 1538 struct block_device *fs_dev, 1539 unsigned long long start, int len, int bsize); 1540 extern journal_t * jbd2_journal_init_inode (struct inode *); 1541 extern int jbd2_journal_update_format (journal_t *); 1542 extern int jbd2_journal_check_used_features 1543 (journal_t *, unsigned long, unsigned long, unsigned long); 1544 extern int jbd2_journal_check_available_features 1545 (journal_t *, unsigned long, unsigned long, unsigned long); 1546 extern int jbd2_journal_set_features 1547 (journal_t *, unsigned long, unsigned long, unsigned long); 1548 extern void jbd2_journal_clear_features 1549 (journal_t *, unsigned long, unsigned long, unsigned long); 1550 extern int jbd2_journal_load (journal_t *journal); 1551 extern int jbd2_journal_destroy (journal_t *); 1552 extern int jbd2_journal_recover (journal_t *journal); 1553 extern int jbd2_journal_wipe (journal_t *, int); 1554 extern int jbd2_journal_skip_recovery (journal_t *); 1555 extern void jbd2_journal_update_sb_errno(journal_t *); 1556 extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t, 1557 unsigned long, blk_opf_t); 1558 extern void jbd2_journal_abort (journal_t *, int); 1559 extern int jbd2_journal_errno (journal_t *); 1560 extern void jbd2_journal_ack_err (journal_t *); 1561 extern int jbd2_journal_clear_err (journal_t *); 1562 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *); 1563 extern int jbd2_journal_force_commit(journal_t *); 1564 extern int jbd2_journal_force_commit_nested(journal_t *); 1565 extern int jbd2_journal_inode_ranged_write(handle_t *handle, 1566 struct jbd2_inode *inode, loff_t start_byte, 1567 loff_t length); 1568 extern int jbd2_journal_inode_ranged_wait(handle_t *handle, 1569 struct jbd2_inode *inode, loff_t start_byte, 1570 loff_t length); 1571 extern int jbd2_journal_finish_inode_data_buffers( 1572 struct jbd2_inode *jinode); 1573 extern int jbd2_journal_begin_ordered_truncate(journal_t *journal, 1574 struct jbd2_inode *inode, loff_t new_size); 1575 extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode); 1576 extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode); 1577 1578 /* 1579 * journal_head management 1580 */ 1581 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh); 1582 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh); 1583 void jbd2_journal_put_journal_head(struct journal_head *jh); 1584 1585 /* 1586 * handle management 1587 */ 1588 extern struct kmem_cache *jbd2_handle_cache; 1589 1590 static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags) 1591 { 1592 return kmem_cache_zalloc(jbd2_handle_cache, gfp_flags); 1593 } 1594 1595 static inline void jbd2_free_handle(handle_t *handle) 1596 { 1597 kmem_cache_free(jbd2_handle_cache, handle); 1598 } 1599 1600 /* 1601 * jbd2_inode management (optional, for those file systems that want to use 1602 * dynamically allocated jbd2_inode structures) 1603 */ 1604 extern struct kmem_cache *jbd2_inode_cache; 1605 1606 static inline struct jbd2_inode *jbd2_alloc_inode(gfp_t gfp_flags) 1607 { 1608 return kmem_cache_alloc(jbd2_inode_cache, gfp_flags); 1609 } 1610 1611 static inline void jbd2_free_inode(struct jbd2_inode *jinode) 1612 { 1613 kmem_cache_free(jbd2_inode_cache, jinode); 1614 } 1615 1616 /* Primary revoke support */ 1617 #define JOURNAL_REVOKE_DEFAULT_HASH 256 1618 extern int jbd2_journal_init_revoke(journal_t *, int); 1619 extern void jbd2_journal_destroy_revoke_record_cache(void); 1620 extern void jbd2_journal_destroy_revoke_table_cache(void); 1621 extern int __init jbd2_journal_init_revoke_record_cache(void); 1622 extern int __init jbd2_journal_init_revoke_table_cache(void); 1623 1624 extern void jbd2_journal_destroy_revoke(journal_t *); 1625 extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *); 1626 extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *); 1627 extern void jbd2_journal_write_revoke_records(transaction_t *transaction, 1628 struct list_head *log_bufs); 1629 1630 /* Recovery revoke support */ 1631 extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t); 1632 extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t); 1633 extern void jbd2_journal_clear_revoke(journal_t *); 1634 extern void jbd2_journal_switch_revoke_table(journal_t *journal); 1635 extern void jbd2_clear_buffer_revoked_flags(journal_t *journal); 1636 1637 /* 1638 * The log thread user interface: 1639 * 1640 * Request space in the current transaction, and force transaction commit 1641 * transitions on demand. 1642 */ 1643 1644 int jbd2_log_start_commit(journal_t *journal, tid_t tid); 1645 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid); 1646 int jbd2_log_wait_commit(journal_t *journal, tid_t tid); 1647 int jbd2_transaction_committed(journal_t *journal, tid_t tid); 1648 int jbd2_complete_transaction(journal_t *journal, tid_t tid); 1649 int jbd2_log_do_checkpoint(journal_t *journal); 1650 int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid); 1651 1652 void __jbd2_log_wait_for_space(journal_t *journal); 1653 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *); 1654 extern int jbd2_cleanup_journal_tail(journal_t *); 1655 1656 /* Fast commit related APIs */ 1657 int jbd2_fc_begin_commit(journal_t *journal, tid_t tid); 1658 int jbd2_fc_end_commit(journal_t *journal); 1659 int jbd2_fc_end_commit_fallback(journal_t *journal); 1660 int jbd2_fc_get_buf(journal_t *journal, struct buffer_head **bh_out); 1661 int jbd2_submit_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1662 int jbd2_wait_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1663 int jbd2_fc_wait_bufs(journal_t *journal, int num_blks); 1664 int jbd2_fc_release_bufs(journal_t *journal); 1665 1666 static inline int jbd2_journal_get_max_txn_bufs(journal_t *journal) 1667 { 1668 return (journal->j_total_len - journal->j_fc_wbufsize) / 4; 1669 } 1670 1671 /* 1672 * is_journal_abort 1673 * 1674 * Simple test wrapper function to test the JBD2_ABORT state flag. This 1675 * bit, when set, indicates that we have had a fatal error somewhere, 1676 * either inside the journaling layer or indicated to us by the client 1677 * (eg. ext3), and that we and should not commit any further 1678 * transactions. 1679 */ 1680 1681 static inline int is_journal_aborted(journal_t *journal) 1682 { 1683 return journal->j_flags & JBD2_ABORT; 1684 } 1685 1686 static inline int is_handle_aborted(handle_t *handle) 1687 { 1688 if (handle->h_aborted || !handle->h_transaction) 1689 return 1; 1690 return is_journal_aborted(handle->h_transaction->t_journal); 1691 } 1692 1693 static inline void jbd2_journal_abort_handle(handle_t *handle) 1694 { 1695 handle->h_aborted = 1; 1696 } 1697 1698 #endif /* __KERNEL__ */ 1699 1700 /* Comparison functions for transaction IDs: perform comparisons using 1701 * modulo arithmetic so that they work over sequence number wraps. */ 1702 1703 static inline int tid_gt(tid_t x, tid_t y) 1704 { 1705 int difference = (x - y); 1706 return (difference > 0); 1707 } 1708 1709 static inline int tid_geq(tid_t x, tid_t y) 1710 { 1711 int difference = (x - y); 1712 return (difference >= 0); 1713 } 1714 1715 extern int jbd2_journal_blocks_per_page(struct inode *inode); 1716 extern size_t journal_tag_bytes(journal_t *journal); 1717 1718 static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j) 1719 { 1720 return jbd2_has_feature_csum2(j) || jbd2_has_feature_csum3(j); 1721 } 1722 1723 static inline int jbd2_journal_has_csum_v2or3(journal_t *journal) 1724 { 1725 WARN_ON_ONCE(jbd2_journal_has_csum_v2or3_feature(journal) && 1726 journal->j_chksum_driver == NULL); 1727 1728 return journal->j_chksum_driver != NULL; 1729 } 1730 1731 static inline int jbd2_journal_get_num_fc_blks(journal_superblock_t *jsb) 1732 { 1733 int num_fc_blocks = be32_to_cpu(jsb->s_num_fc_blks); 1734 1735 return num_fc_blocks ? num_fc_blocks : JBD2_DEFAULT_FAST_COMMIT_BLOCKS; 1736 } 1737 1738 /* 1739 * Return number of free blocks in the log. Must be called under j_state_lock. 1740 */ 1741 static inline unsigned long jbd2_log_space_left(journal_t *journal) 1742 { 1743 /* Allow for rounding errors */ 1744 long free = journal->j_free - 32; 1745 1746 if (journal->j_committing_transaction) { 1747 free -= atomic_read(&journal-> 1748 j_committing_transaction->t_outstanding_credits); 1749 } 1750 return max_t(long, free, 0); 1751 } 1752 1753 /* 1754 * Definitions which augment the buffer_head layer 1755 */ 1756 1757 /* journaling buffer types */ 1758 #define BJ_None 0 /* Not journaled */ 1759 #define BJ_Metadata 1 /* Normal journaled metadata */ 1760 #define BJ_Forget 2 /* Buffer superseded by this transaction */ 1761 #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */ 1762 #define BJ_Reserved 4 /* Buffer is reserved for access by journal */ 1763 #define BJ_Types 5 1764 1765 /* JBD uses a CRC32 checksum */ 1766 #define JBD_MAX_CHECKSUM_SIZE 4 1767 1768 static inline u32 jbd2_chksum(journal_t *journal, u32 crc, 1769 const void *address, unsigned int length) 1770 { 1771 struct { 1772 struct shash_desc shash; 1773 char ctx[JBD_MAX_CHECKSUM_SIZE]; 1774 } desc; 1775 int err; 1776 1777 BUG_ON(crypto_shash_descsize(journal->j_chksum_driver) > 1778 JBD_MAX_CHECKSUM_SIZE); 1779 1780 desc.shash.tfm = journal->j_chksum_driver; 1781 *(u32 *)desc.ctx = crc; 1782 1783 err = crypto_shash_update(&desc.shash, address, length); 1784 BUG_ON(err); 1785 1786 return *(u32 *)desc.ctx; 1787 } 1788 1789 /* Return most recent uncommitted transaction */ 1790 static inline tid_t jbd2_get_latest_transaction(journal_t *journal) 1791 { 1792 tid_t tid; 1793 1794 read_lock(&journal->j_state_lock); 1795 tid = journal->j_commit_request; 1796 if (journal->j_running_transaction) 1797 tid = journal->j_running_transaction->t_tid; 1798 read_unlock(&journal->j_state_lock); 1799 return tid; 1800 } 1801 1802 static inline int jbd2_handle_buffer_credits(handle_t *handle) 1803 { 1804 journal_t *journal; 1805 1806 if (!handle->h_reserved) 1807 journal = handle->h_transaction->t_journal; 1808 else 1809 journal = handle->h_journal; 1810 1811 return handle->h_total_credits - 1812 DIV_ROUND_UP(handle->h_revoke_credits_requested, 1813 journal->j_revoke_records_per_block); 1814 } 1815 1816 #ifdef __KERNEL__ 1817 1818 #define buffer_trace_init(bh) do {} while (0) 1819 #define print_buffer_fields(bh) do {} while (0) 1820 #define print_buffer_trace(bh) do {} while (0) 1821 #define BUFFER_TRACE(bh, info) do {} while (0) 1822 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0) 1823 #define JBUFFER_TRACE(jh, info) do {} while (0) 1824 1825 #endif /* __KERNEL__ */ 1826 1827 #define EFSBADCRC EBADMSG /* Bad CRC detected */ 1828 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ 1829 1830 #endif /* _LINUX_JBD2_H */ 1831