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 extern ushort jbd2_journal_enable_debug; 58 void __jbd2_debug(int level, const char *file, const char *func, 59 unsigned int line, const char *fmt, ...); 60 61 #define jbd_debug(n, fmt, a...) \ 62 __jbd2_debug((n), __FILE__, __func__, __LINE__, (fmt), ##a) 63 #else 64 #define jbd_debug(n, fmt, a...) /**/ 65 #endif 66 67 extern void *jbd2_alloc(size_t size, gfp_t flags); 68 extern void jbd2_free(void *ptr, size_t size); 69 70 #define JBD2_MIN_JOURNAL_BLOCKS 1024 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 __u32 s_padding[42]; 267 __be32 s_checksum; /* crc32c(superblock) */ 268 269 /* 0x0100 */ 270 __u8 s_users[16*48]; /* ids of all fs'es sharing the log */ 271 /* 0x0400 */ 272 } journal_superblock_t; 273 274 /* Use the jbd2_{has,set,clear}_feature_* helpers; these will be removed */ 275 #define JBD2_HAS_COMPAT_FEATURE(j,mask) \ 276 ((j)->j_format_version >= 2 && \ 277 ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask)))) 278 #define JBD2_HAS_RO_COMPAT_FEATURE(j,mask) \ 279 ((j)->j_format_version >= 2 && \ 280 ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask)))) 281 #define JBD2_HAS_INCOMPAT_FEATURE(j,mask) \ 282 ((j)->j_format_version >= 2 && \ 283 ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask)))) 284 285 #define JBD2_FEATURE_COMPAT_CHECKSUM 0x00000001 286 287 #define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001 288 #define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002 289 #define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT 0x00000004 290 #define JBD2_FEATURE_INCOMPAT_CSUM_V2 0x00000008 291 #define JBD2_FEATURE_INCOMPAT_CSUM_V3 0x00000010 292 #define JBD2_FEATURE_INCOMPAT_FAST_COMMIT 0x00000020 293 294 /* See "journal feature predicate functions" below */ 295 296 /* Features known to this kernel version: */ 297 #define JBD2_KNOWN_COMPAT_FEATURES JBD2_FEATURE_COMPAT_CHECKSUM 298 #define JBD2_KNOWN_ROCOMPAT_FEATURES 0 299 #define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \ 300 JBD2_FEATURE_INCOMPAT_64BIT | \ 301 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | \ 302 JBD2_FEATURE_INCOMPAT_CSUM_V2 | \ 303 JBD2_FEATURE_INCOMPAT_CSUM_V3 | \ 304 JBD2_FEATURE_INCOMPAT_FAST_COMMIT) 305 306 #ifdef __KERNEL__ 307 308 #include <linux/fs.h> 309 #include <linux/sched.h> 310 311 enum jbd_state_bits { 312 BH_JBD /* Has an attached ext3 journal_head */ 313 = BH_PrivateStart, 314 BH_JWrite, /* Being written to log (@@@ DEBUGGING) */ 315 BH_Freed, /* Has been freed (truncated) */ 316 BH_Revoked, /* Has been revoked from the log */ 317 BH_RevokeValid, /* Revoked flag is valid */ 318 BH_JBDDirty, /* Is dirty but journaled */ 319 BH_JournalHead, /* Pins bh->b_private and jh->b_bh */ 320 BH_Shadow, /* IO on shadow buffer is running */ 321 BH_Verified, /* Metadata block has been verified ok */ 322 BH_JBDPrivateStart, /* First bit available for private use by FS */ 323 }; 324 325 BUFFER_FNS(JBD, jbd) 326 BUFFER_FNS(JWrite, jwrite) 327 BUFFER_FNS(JBDDirty, jbddirty) 328 TAS_BUFFER_FNS(JBDDirty, jbddirty) 329 BUFFER_FNS(Revoked, revoked) 330 TAS_BUFFER_FNS(Revoked, revoked) 331 BUFFER_FNS(RevokeValid, revokevalid) 332 TAS_BUFFER_FNS(RevokeValid, revokevalid) 333 BUFFER_FNS(Freed, freed) 334 BUFFER_FNS(Shadow, shadow) 335 BUFFER_FNS(Verified, verified) 336 337 static inline struct buffer_head *jh2bh(struct journal_head *jh) 338 { 339 return jh->b_bh; 340 } 341 342 static inline struct journal_head *bh2jh(struct buffer_head *bh) 343 { 344 return bh->b_private; 345 } 346 347 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh) 348 { 349 bit_spin_lock(BH_JournalHead, &bh->b_state); 350 } 351 352 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh) 353 { 354 bit_spin_unlock(BH_JournalHead, &bh->b_state); 355 } 356 357 #define J_ASSERT(assert) BUG_ON(!(assert)) 358 359 #define J_ASSERT_BH(bh, expr) J_ASSERT(expr) 360 #define J_ASSERT_JH(jh, expr) J_ASSERT(expr) 361 362 #if defined(JBD2_PARANOID_IOFAIL) 363 #define J_EXPECT(expr, why...) J_ASSERT(expr) 364 #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr) 365 #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr) 366 #else 367 #define __journal_expect(expr, why...) \ 368 ({ \ 369 int val = (expr); \ 370 if (!val) { \ 371 printk(KERN_ERR \ 372 "JBD2 unexpected failure: %s: %s;\n", \ 373 __func__, #expr); \ 374 printk(KERN_ERR why "\n"); \ 375 } \ 376 val; \ 377 }) 378 #define J_EXPECT(expr, why...) __journal_expect(expr, ## why) 379 #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why) 380 #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why) 381 #endif 382 383 /* Flags in jbd_inode->i_flags */ 384 #define __JI_COMMIT_RUNNING 0 385 #define __JI_WRITE_DATA 1 386 #define __JI_WAIT_DATA 2 387 388 /* 389 * Commit of the inode data in progress. We use this flag to protect us from 390 * concurrent deletion of inode. We cannot use reference to inode for this 391 * since we cannot afford doing last iput() on behalf of kjournald 392 */ 393 #define JI_COMMIT_RUNNING (1 << __JI_COMMIT_RUNNING) 394 /* Write allocated dirty buffers in this inode before commit */ 395 #define JI_WRITE_DATA (1 << __JI_WRITE_DATA) 396 /* Wait for outstanding data writes for this inode before commit */ 397 #define JI_WAIT_DATA (1 << __JI_WAIT_DATA) 398 399 /** 400 * struct jbd_inode - The jbd_inode type is the structure linking inodes in 401 * ordered mode present in a transaction so that we can sync them during commit. 402 */ 403 struct jbd2_inode { 404 /** 405 * @i_transaction: 406 * 407 * Which transaction does this inode belong to? Either the running 408 * transaction or the committing one. [j_list_lock] 409 */ 410 transaction_t *i_transaction; 411 412 /** 413 * @i_next_transaction: 414 * 415 * Pointer to the running transaction modifying inode's data in case 416 * there is already a committing transaction touching it. [j_list_lock] 417 */ 418 transaction_t *i_next_transaction; 419 420 /** 421 * @i_list: List of inodes in the i_transaction [j_list_lock] 422 */ 423 struct list_head i_list; 424 425 /** 426 * @i_vfs_inode: 427 * 428 * VFS inode this inode belongs to [constant for lifetime of structure] 429 */ 430 struct inode *i_vfs_inode; 431 432 /** 433 * @i_flags: Flags of inode [j_list_lock] 434 */ 435 unsigned long i_flags; 436 437 /** 438 * @i_dirty_start: 439 * 440 * Offset in bytes where the dirty range for this inode starts. 441 * [j_list_lock] 442 */ 443 loff_t i_dirty_start; 444 445 /** 446 * @i_dirty_end: 447 * 448 * Inclusive offset in bytes where the dirty range for this inode 449 * ends. [j_list_lock] 450 */ 451 loff_t i_dirty_end; 452 }; 453 454 struct jbd2_revoke_table_s; 455 456 /** 457 * struct jbd2_journal_handle - The jbd2_journal_handle type is the concrete 458 * type associated with handle_t. 459 * @h_transaction: Which compound transaction is this update a part of? 460 * @h_journal: Which journal handle belongs to - used iff h_reserved set. 461 * @h_rsv_handle: Handle reserved for finishing the logical operation. 462 * @h_total_credits: Number of remaining buffers we are allowed to add to 463 * journal. These are dirty buffers and revoke descriptor blocks. 464 * @h_revoke_credits: Number of remaining revoke records available for handle 465 * @h_ref: Reference count on this handle. 466 * @h_err: Field for caller's use to track errors through large fs operations. 467 * @h_sync: Flag for sync-on-close. 468 * @h_jdata: Flag to force data journaling. 469 * @h_reserved: Flag for handle for reserved credits. 470 * @h_aborted: Flag indicating fatal error on handle. 471 * @h_type: For handle statistics. 472 * @h_line_no: For handle statistics. 473 * @h_start_jiffies: Handle Start time. 474 * @h_requested_credits: Holds @h_total_credits after handle is started. 475 * @h_revoke_credits_requested: Holds @h_revoke_credits after handle is started. 476 * @saved_alloc_context: Saved context while transaction is open. 477 **/ 478 479 /* Docbook can't yet cope with the bit fields, but will leave the documentation 480 * in so it can be fixed later. 481 */ 482 483 struct jbd2_journal_handle 484 { 485 union { 486 transaction_t *h_transaction; 487 /* Which journal handle belongs to - used iff h_reserved set */ 488 journal_t *h_journal; 489 }; 490 491 handle_t *h_rsv_handle; 492 int h_total_credits; 493 int h_revoke_credits; 494 int h_revoke_credits_requested; 495 int h_ref; 496 int h_err; 497 498 /* Flags [no locking] */ 499 unsigned int h_sync: 1; 500 unsigned int h_jdata: 1; 501 unsigned int h_reserved: 1; 502 unsigned int h_aborted: 1; 503 unsigned int h_type: 8; 504 unsigned int h_line_no: 16; 505 506 unsigned long h_start_jiffies; 507 unsigned int h_requested_credits; 508 509 unsigned int saved_alloc_context; 510 }; 511 512 513 /* 514 * Some stats for checkpoint phase 515 */ 516 struct transaction_chp_stats_s { 517 unsigned long cs_chp_time; 518 __u32 cs_forced_to_close; 519 __u32 cs_written; 520 __u32 cs_dropped; 521 }; 522 523 /* The transaction_t type is the guts of the journaling mechanism. It 524 * tracks a compound transaction through its various states: 525 * 526 * RUNNING: accepting new updates 527 * LOCKED: Updates still running but we don't accept new ones 528 * RUNDOWN: Updates are tidying up but have finished requesting 529 * new buffers to modify (state not used for now) 530 * FLUSH: All updates complete, but we are still writing to disk 531 * COMMIT: All data on disk, writing commit record 532 * FINISHED: We still have to keep the transaction for checkpointing. 533 * 534 * The transaction keeps track of all of the buffers modified by a 535 * running transaction, and all of the buffers committed but not yet 536 * flushed to home for finished transactions. 537 */ 538 539 /* 540 * Lock ranking: 541 * 542 * j_list_lock 543 * ->jbd_lock_bh_journal_head() (This is "innermost") 544 * 545 * j_state_lock 546 * ->b_state_lock 547 * 548 * b_state_lock 549 * ->j_list_lock 550 * 551 * j_state_lock 552 * ->t_handle_lock 553 * 554 * j_state_lock 555 * ->j_list_lock (journal_unmap_buffer) 556 * 557 */ 558 559 struct transaction_s 560 { 561 /* Pointer to the journal for this transaction. [no locking] */ 562 journal_t *t_journal; 563 564 /* Sequence number for this transaction [no locking] */ 565 tid_t t_tid; 566 567 /* 568 * Transaction's current state 569 * [no locking - only kjournald2 alters this] 570 * [j_list_lock] guards transition of a transaction into T_FINISHED 571 * state and subsequent call of __jbd2_journal_drop_transaction() 572 * FIXME: needs barriers 573 * KLUDGE: [use j_state_lock] 574 */ 575 enum { 576 T_RUNNING, 577 T_LOCKED, 578 T_SWITCH, 579 T_FLUSH, 580 T_COMMIT, 581 T_COMMIT_DFLUSH, 582 T_COMMIT_JFLUSH, 583 T_COMMIT_CALLBACK, 584 T_FINISHED 585 } t_state; 586 587 /* 588 * Where in the log does this transaction's commit start? [no locking] 589 */ 590 unsigned long t_log_start; 591 592 /* Number of buffers on the t_buffers list [j_list_lock] */ 593 int t_nr_buffers; 594 595 /* 596 * Doubly-linked circular list of all buffers reserved but not yet 597 * modified by this transaction [j_list_lock] 598 */ 599 struct journal_head *t_reserved_list; 600 601 /* 602 * Doubly-linked circular list of all metadata buffers owned by this 603 * transaction [j_list_lock] 604 */ 605 struct journal_head *t_buffers; 606 607 /* 608 * Doubly-linked circular list of all forget buffers (superseded 609 * buffers which we can un-checkpoint once this transaction commits) 610 * [j_list_lock] 611 */ 612 struct journal_head *t_forget; 613 614 /* 615 * Doubly-linked circular list of all buffers still to be flushed before 616 * this transaction can be checkpointed. [j_list_lock] 617 */ 618 struct journal_head *t_checkpoint_list; 619 620 /* 621 * Doubly-linked circular list of all buffers submitted for IO while 622 * checkpointing. [j_list_lock] 623 */ 624 struct journal_head *t_checkpoint_io_list; 625 626 /* 627 * Doubly-linked circular list of metadata buffers being shadowed by log 628 * IO. The IO buffers on the iobuf list and the shadow buffers on this 629 * list match each other one for one at all times. [j_list_lock] 630 */ 631 struct journal_head *t_shadow_list; 632 633 /* 634 * List of inodes associated with the transaction; e.g., ext4 uses 635 * this to track inodes in data=ordered and data=journal mode that 636 * need special handling on transaction commit; also used by ocfs2. 637 * [j_list_lock] 638 */ 639 struct list_head t_inode_list; 640 641 /* 642 * Protects info related to handles 643 */ 644 spinlock_t t_handle_lock; 645 646 /* 647 * Longest time some handle had to wait for running transaction 648 */ 649 unsigned long t_max_wait; 650 651 /* 652 * When transaction started 653 */ 654 unsigned long t_start; 655 656 /* 657 * When commit was requested 658 */ 659 unsigned long t_requested; 660 661 /* 662 * Checkpointing stats [j_checkpoint_sem] 663 */ 664 struct transaction_chp_stats_s t_chp_stats; 665 666 /* 667 * Number of outstanding updates running on this transaction 668 * [none] 669 */ 670 atomic_t t_updates; 671 672 /* 673 * Number of blocks reserved for this transaction in the journal. 674 * This is including all credits reserved when starting transaction 675 * handles as well as all journal descriptor blocks needed for this 676 * transaction. [none] 677 */ 678 atomic_t t_outstanding_credits; 679 680 /* 681 * Number of revoke records for this transaction added by already 682 * stopped handles. [none] 683 */ 684 atomic_t t_outstanding_revokes; 685 686 /* 687 * How many handles used this transaction? [none] 688 */ 689 atomic_t t_handle_count; 690 691 /* 692 * Forward and backward links for the circular list of all transactions 693 * awaiting checkpoint. [j_list_lock] 694 */ 695 transaction_t *t_cpnext, *t_cpprev; 696 697 /* 698 * When will the transaction expire (become due for commit), in jiffies? 699 * [no locking] 700 */ 701 unsigned long t_expires; 702 703 /* 704 * When this transaction started, in nanoseconds [no locking] 705 */ 706 ktime_t t_start_time; 707 708 /* 709 * This transaction is being forced and some process is 710 * waiting for it to finish. 711 */ 712 unsigned int t_synchronous_commit:1; 713 714 /* Disk flush needs to be sent to fs partition [no locking] */ 715 int t_need_data_flush; 716 717 /* 718 * For use by the filesystem to store fs-specific data 719 * structures associated with the transaction 720 */ 721 struct list_head t_private_list; 722 }; 723 724 struct transaction_run_stats_s { 725 unsigned long rs_wait; 726 unsigned long rs_request_delay; 727 unsigned long rs_running; 728 unsigned long rs_locked; 729 unsigned long rs_flushing; 730 unsigned long rs_logging; 731 732 __u32 rs_handle_count; 733 __u32 rs_blocks; 734 __u32 rs_blocks_logged; 735 }; 736 737 struct transaction_stats_s { 738 unsigned long ts_tid; 739 unsigned long ts_requested; 740 struct transaction_run_stats_s run; 741 }; 742 743 static inline unsigned long 744 jbd2_time_diff(unsigned long start, unsigned long end) 745 { 746 if (end >= start) 747 return end - start; 748 749 return end + (MAX_JIFFY_OFFSET - start); 750 } 751 752 #define JBD2_NR_BATCH 64 753 754 enum passtype {PASS_SCAN, PASS_REVOKE, PASS_REPLAY}; 755 756 #define JBD2_FC_REPLAY_STOP 0 757 #define JBD2_FC_REPLAY_CONTINUE 1 758 759 /** 760 * struct journal_s - The journal_s type is the concrete type associated with 761 * journal_t. 762 */ 763 struct journal_s 764 { 765 /** 766 * @j_flags: General journaling state flags [j_state_lock] 767 */ 768 unsigned long j_flags; 769 770 /** 771 * @j_errno: 772 * 773 * Is there an outstanding uncleared error on the journal (from a prior 774 * abort)? [j_state_lock] 775 */ 776 int j_errno; 777 778 /** 779 * @j_abort_mutex: Lock the whole aborting procedure. 780 */ 781 struct mutex j_abort_mutex; 782 783 /** 784 * @j_sb_buffer: The first part of the superblock buffer. 785 */ 786 struct buffer_head *j_sb_buffer; 787 788 /** 789 * @j_superblock: The second part of the superblock buffer. 790 */ 791 journal_superblock_t *j_superblock; 792 793 /** 794 * @j_format_version: Version of the superblock format. 795 */ 796 int j_format_version; 797 798 /** 799 * @j_state_lock: Protect the various scalars in the journal. 800 */ 801 rwlock_t j_state_lock; 802 803 /** 804 * @j_barrier_count: 805 * 806 * Number of processes waiting to create a barrier lock [j_state_lock] 807 */ 808 int j_barrier_count; 809 810 /** 811 * @j_barrier: The barrier lock itself. 812 */ 813 struct mutex j_barrier; 814 815 /** 816 * @j_running_transaction: 817 * 818 * Transactions: The current running transaction... 819 * [j_state_lock] [caller holding open handle] 820 */ 821 transaction_t *j_running_transaction; 822 823 /** 824 * @j_committing_transaction: 825 * 826 * the transaction we are pushing to disk 827 * [j_state_lock] [caller holding open handle] 828 */ 829 transaction_t *j_committing_transaction; 830 831 /** 832 * @j_checkpoint_transactions: 833 * 834 * ... and a linked circular list of all transactions waiting for 835 * checkpointing. [j_list_lock] 836 */ 837 transaction_t *j_checkpoint_transactions; 838 839 /** 840 * @j_wait_transaction_locked: 841 * 842 * Wait queue for waiting for a locked transaction to start committing, 843 * or for a barrier lock to be released. 844 */ 845 wait_queue_head_t j_wait_transaction_locked; 846 847 /** 848 * @j_wait_done_commit: Wait queue for waiting for commit to complete. 849 */ 850 wait_queue_head_t j_wait_done_commit; 851 852 /** 853 * @j_wait_commit: Wait queue to trigger commit. 854 */ 855 wait_queue_head_t j_wait_commit; 856 857 /** 858 * @j_wait_updates: Wait queue to wait for updates to complete. 859 */ 860 wait_queue_head_t j_wait_updates; 861 862 /** 863 * @j_wait_reserved: 864 * 865 * Wait queue to wait for reserved buffer credits to drop. 866 */ 867 wait_queue_head_t j_wait_reserved; 868 869 /** 870 * @j_fc_wait: 871 * 872 * Wait queue to wait for completion of async fast commits. 873 */ 874 wait_queue_head_t j_fc_wait; 875 876 /** 877 * @j_checkpoint_mutex: 878 * 879 * Semaphore for locking against concurrent checkpoints. 880 */ 881 struct mutex j_checkpoint_mutex; 882 883 /** 884 * @j_chkpt_bhs: 885 * 886 * List of buffer heads used by the checkpoint routine. This 887 * was moved from jbd2_log_do_checkpoint() to reduce stack 888 * usage. Access to this array is controlled by the 889 * @j_checkpoint_mutex. [j_checkpoint_mutex] 890 */ 891 struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH]; 892 893 /** 894 * @j_head: 895 * 896 * Journal head: identifies the first unused block in the journal. 897 * [j_state_lock] 898 */ 899 unsigned long j_head; 900 901 /** 902 * @j_tail: 903 * 904 * Journal tail: identifies the oldest still-used block in the journal. 905 * [j_state_lock] 906 */ 907 unsigned long j_tail; 908 909 /** 910 * @j_free: 911 * 912 * Journal free: how many free blocks are there in the journal? 913 * [j_state_lock] 914 */ 915 unsigned long j_free; 916 917 /** 918 * @j_first: 919 * 920 * The block number of the first usable block in the journal 921 * [j_state_lock]. 922 */ 923 unsigned long j_first; 924 925 /** 926 * @j_last: 927 * 928 * The block number one beyond the last usable block in the journal 929 * [j_state_lock]. 930 */ 931 unsigned long j_last; 932 933 /** 934 * @j_fc_first: 935 * 936 * The block number of the first fast commit block in the journal 937 * [j_state_lock]. 938 */ 939 unsigned long j_fc_first; 940 941 /** 942 * @j_fc_off: 943 * 944 * Number of fast commit blocks currently allocated. 945 * [j_state_lock]. 946 */ 947 unsigned long j_fc_off; 948 949 /** 950 * @j_fc_last: 951 * 952 * The block number one beyond the last fast commit block in the journal 953 * [j_state_lock]. 954 */ 955 unsigned long j_fc_last; 956 957 /** 958 * @j_dev: Device where we store the journal. 959 */ 960 struct block_device *j_dev; 961 962 /** 963 * @j_blocksize: Block size for the location where we store the journal. 964 */ 965 int j_blocksize; 966 967 /** 968 * @j_blk_offset: 969 * 970 * Starting block offset into the device where we store the journal. 971 */ 972 unsigned long long j_blk_offset; 973 974 /** 975 * @j_devname: Journal device name. 976 */ 977 char j_devname[BDEVNAME_SIZE+24]; 978 979 /** 980 * @j_fs_dev: 981 * 982 * Device which holds the client fs. For internal journal this will be 983 * equal to j_dev. 984 */ 985 struct block_device *j_fs_dev; 986 987 /** 988 * @j_maxlen: Total maximum capacity of the journal region on disk. 989 */ 990 unsigned int j_maxlen; 991 992 /** 993 * @j_reserved_credits: 994 * 995 * Number of buffers reserved from the running transaction. 996 */ 997 atomic_t j_reserved_credits; 998 999 /** 1000 * @j_list_lock: Protects the buffer lists and internal buffer state. 1001 */ 1002 spinlock_t j_list_lock; 1003 1004 /** 1005 * @j_inode: 1006 * 1007 * Optional inode where we store the journal. If present, all 1008 * journal block numbers are mapped into this inode via bmap(). 1009 */ 1010 struct inode *j_inode; 1011 1012 /** 1013 * @j_tail_sequence: 1014 * 1015 * Sequence number of the oldest transaction in the log [j_state_lock] 1016 */ 1017 tid_t j_tail_sequence; 1018 1019 /** 1020 * @j_transaction_sequence: 1021 * 1022 * Sequence number of the next transaction to grant [j_state_lock] 1023 */ 1024 tid_t j_transaction_sequence; 1025 1026 /** 1027 * @j_commit_sequence: 1028 * 1029 * Sequence number of the most recently committed transaction 1030 * [j_state_lock]. 1031 */ 1032 tid_t j_commit_sequence; 1033 1034 /** 1035 * @j_commit_request: 1036 * 1037 * Sequence number of the most recent transaction wanting commit 1038 * [j_state_lock] 1039 */ 1040 tid_t j_commit_request; 1041 1042 /** 1043 * @j_uuid: 1044 * 1045 * Journal uuid: identifies the object (filesystem, LVM volume etc) 1046 * backed by this journal. This will eventually be replaced by an array 1047 * of uuids, allowing us to index multiple devices within a single 1048 * journal and to perform atomic updates across them. 1049 */ 1050 __u8 j_uuid[16]; 1051 1052 /** 1053 * @j_task: Pointer to the current commit thread for this journal. 1054 */ 1055 struct task_struct *j_task; 1056 1057 /** 1058 * @j_max_transaction_buffers: 1059 * 1060 * Maximum number of metadata buffers to allow in a single compound 1061 * commit transaction. 1062 */ 1063 int j_max_transaction_buffers; 1064 1065 /** 1066 * @j_revoke_records_per_block: 1067 * 1068 * Number of revoke records that fit in one descriptor block. 1069 */ 1070 int j_revoke_records_per_block; 1071 1072 /** 1073 * @j_commit_interval: 1074 * 1075 * What is the maximum transaction lifetime before we begin a commit? 1076 */ 1077 unsigned long j_commit_interval; 1078 1079 /** 1080 * @j_commit_timer: The timer used to wakeup the commit thread. 1081 */ 1082 struct timer_list j_commit_timer; 1083 1084 /** 1085 * @j_revoke_lock: Protect the revoke table. 1086 */ 1087 spinlock_t j_revoke_lock; 1088 1089 /** 1090 * @j_revoke: 1091 * 1092 * The revoke table - maintains the list of revoked blocks in the 1093 * current transaction. 1094 */ 1095 struct jbd2_revoke_table_s *j_revoke; 1096 1097 /** 1098 * @j_revoke_table: Alternate revoke tables for j_revoke. 1099 */ 1100 struct jbd2_revoke_table_s *j_revoke_table[2]; 1101 1102 /** 1103 * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction. 1104 */ 1105 struct buffer_head **j_wbuf; 1106 1107 /** 1108 * @j_fc_wbuf: Array of fast commit bhs for 1109 * jbd2_journal_commit_transaction. 1110 */ 1111 struct buffer_head **j_fc_wbuf; 1112 1113 /** 1114 * @j_wbufsize: 1115 * 1116 * Size of @j_wbuf array. 1117 */ 1118 int j_wbufsize; 1119 1120 /** 1121 * @j_fc_wbufsize: 1122 * 1123 * Size of @j_fc_wbuf array. 1124 */ 1125 int j_fc_wbufsize; 1126 1127 /** 1128 * @j_last_sync_writer: 1129 * 1130 * The pid of the last person to run a synchronous operation 1131 * through the journal. 1132 */ 1133 pid_t j_last_sync_writer; 1134 1135 /** 1136 * @j_average_commit_time: 1137 * 1138 * The average amount of time in nanoseconds it takes to commit a 1139 * transaction to disk. [j_state_lock] 1140 */ 1141 u64 j_average_commit_time; 1142 1143 /** 1144 * @j_min_batch_time: 1145 * 1146 * Minimum time that we should wait for additional filesystem operations 1147 * to get batched into a synchronous handle in microseconds. 1148 */ 1149 u32 j_min_batch_time; 1150 1151 /** 1152 * @j_max_batch_time: 1153 * 1154 * Maximum time that we should wait for additional filesystem operations 1155 * to get batched into a synchronous handle in microseconds. 1156 */ 1157 u32 j_max_batch_time; 1158 1159 /** 1160 * @j_commit_callback: 1161 * 1162 * This function is called when a transaction is closed. 1163 */ 1164 void (*j_commit_callback)(journal_t *, 1165 transaction_t *); 1166 1167 /** 1168 * @j_submit_inode_data_buffers: 1169 * 1170 * This function is called for all inodes associated with the 1171 * committing transaction marked with JI_WRITE_DATA flag 1172 * before we start to write out the transaction to the journal. 1173 */ 1174 int (*j_submit_inode_data_buffers) 1175 (struct jbd2_inode *); 1176 1177 /** 1178 * @j_finish_inode_data_buffers: 1179 * 1180 * This function is called for all inodes associated with the 1181 * committing transaction marked with JI_WAIT_DATA flag 1182 * after we have written the transaction to the journal 1183 * but before we write out the commit block. 1184 */ 1185 int (*j_finish_inode_data_buffers) 1186 (struct jbd2_inode *); 1187 1188 /* 1189 * Journal statistics 1190 */ 1191 1192 /** 1193 * @j_history_lock: Protect the transactions statistics history. 1194 */ 1195 spinlock_t j_history_lock; 1196 1197 /** 1198 * @j_proc_entry: procfs entry for the jbd statistics directory. 1199 */ 1200 struct proc_dir_entry *j_proc_entry; 1201 1202 /** 1203 * @j_stats: Overall statistics. 1204 */ 1205 struct transaction_stats_s j_stats; 1206 1207 /** 1208 * @j_failed_commit: Failed journal commit ID. 1209 */ 1210 unsigned int j_failed_commit; 1211 1212 /** 1213 * @j_private: 1214 * 1215 * An opaque pointer to fs-private information. ext3 puts its 1216 * superblock pointer here. 1217 */ 1218 void *j_private; 1219 1220 /** 1221 * @j_chksum_driver: 1222 * 1223 * Reference to checksum algorithm driver via cryptoapi. 1224 */ 1225 struct crypto_shash *j_chksum_driver; 1226 1227 /** 1228 * @j_csum_seed: 1229 * 1230 * Precomputed journal UUID checksum for seeding other checksums. 1231 */ 1232 __u32 j_csum_seed; 1233 1234 #ifdef CONFIG_DEBUG_LOCK_ALLOC 1235 /** 1236 * @j_trans_commit_map: 1237 * 1238 * Lockdep entity to track transaction commit dependencies. Handles 1239 * hold this "lock" for read, when we wait for commit, we acquire the 1240 * "lock" for writing. This matches the properties of jbd2 journalling 1241 * where the running transaction has to wait for all handles to be 1242 * dropped to commit that transaction and also acquiring a handle may 1243 * require transaction commit to finish. 1244 */ 1245 struct lockdep_map j_trans_commit_map; 1246 #endif 1247 1248 /** 1249 * @j_fc_cleanup_callback: 1250 * 1251 * Clean-up after fast commit or full commit. JBD2 calls this function 1252 * after every commit operation. 1253 */ 1254 void (*j_fc_cleanup_callback)(struct journal_s *journal, int); 1255 1256 /* 1257 * @j_fc_replay_callback: 1258 * 1259 * File-system specific function that performs replay of a fast 1260 * commit. JBD2 calls this function for each fast commit block found in 1261 * the journal. This function should return JBD2_FC_REPLAY_CONTINUE 1262 * to indicate that the block was processed correctly and more fast 1263 * commit replay should continue. Return value of JBD2_FC_REPLAY_STOP 1264 * indicates the end of replay (no more blocks remaining). A negative 1265 * return value indicates error. 1266 */ 1267 int (*j_fc_replay_callback)(struct journal_s *journal, 1268 struct buffer_head *bh, 1269 enum passtype pass, int off, 1270 tid_t expected_commit_id); 1271 }; 1272 1273 #define jbd2_might_wait_for_commit(j) \ 1274 do { \ 1275 rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \ 1276 rwsem_release(&j->j_trans_commit_map, _THIS_IP_); \ 1277 } while (0) 1278 1279 /* journal feature predicate functions */ 1280 #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \ 1281 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1282 { \ 1283 return ((j)->j_format_version >= 2 && \ 1284 ((j)->j_superblock->s_feature_compat & \ 1285 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \ 1286 } \ 1287 static inline void jbd2_set_feature_##name(journal_t *j) \ 1288 { \ 1289 (j)->j_superblock->s_feature_compat |= \ 1290 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1291 } \ 1292 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1293 { \ 1294 (j)->j_superblock->s_feature_compat &= \ 1295 ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1296 } 1297 1298 #define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \ 1299 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1300 { \ 1301 return ((j)->j_format_version >= 2 && \ 1302 ((j)->j_superblock->s_feature_ro_compat & \ 1303 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \ 1304 } \ 1305 static inline void jbd2_set_feature_##name(journal_t *j) \ 1306 { \ 1307 (j)->j_superblock->s_feature_ro_compat |= \ 1308 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1309 } \ 1310 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1311 { \ 1312 (j)->j_superblock->s_feature_ro_compat &= \ 1313 ~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1314 } 1315 1316 #define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \ 1317 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1318 { \ 1319 return ((j)->j_format_version >= 2 && \ 1320 ((j)->j_superblock->s_feature_incompat & \ 1321 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \ 1322 } \ 1323 static inline void jbd2_set_feature_##name(journal_t *j) \ 1324 { \ 1325 (j)->j_superblock->s_feature_incompat |= \ 1326 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1327 } \ 1328 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1329 { \ 1330 (j)->j_superblock->s_feature_incompat &= \ 1331 ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1332 } 1333 1334 JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM) 1335 1336 JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE) 1337 JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT) 1338 JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT) 1339 JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2) 1340 JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3) 1341 JBD2_FEATURE_INCOMPAT_FUNCS(fast_commit, FAST_COMMIT) 1342 1343 /* 1344 * Journal flag definitions 1345 */ 1346 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */ 1347 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */ 1348 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */ 1349 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */ 1350 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */ 1351 #define JBD2_BARRIER 0x020 /* Use IDE barriers */ 1352 #define JBD2_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file 1353 * data write error in ordered 1354 * mode */ 1355 #define JBD2_FAST_COMMIT_ONGOING 0x100 /* Fast commit is ongoing */ 1356 #define JBD2_FULL_COMMIT_ONGOING 0x200 /* Full commit is ongoing */ 1357 1358 /* 1359 * Function declarations for the journaling transaction and buffer 1360 * management 1361 */ 1362 1363 /* Filing buffers */ 1364 extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *); 1365 extern bool __jbd2_journal_refile_buffer(struct journal_head *); 1366 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *); 1367 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1368 extern void __journal_free_buffer(struct journal_head *bh); 1369 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1370 extern void __journal_clean_data_list(transaction_t *transaction); 1371 static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh) 1372 { 1373 list_add_tail(&bh->b_assoc_buffers, head); 1374 } 1375 static inline void jbd2_unfile_log_bh(struct buffer_head *bh) 1376 { 1377 list_del_init(&bh->b_assoc_buffers); 1378 } 1379 1380 /* Log buffer allocation */ 1381 struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int); 1382 void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *); 1383 int jbd2_journal_next_log_block(journal_t *, unsigned long long *); 1384 int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, 1385 unsigned long *block); 1386 int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1387 void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1388 1389 /* Commit management */ 1390 extern void jbd2_journal_commit_transaction(journal_t *); 1391 1392 /* Checkpoint list management */ 1393 void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy); 1394 int __jbd2_journal_remove_checkpoint(struct journal_head *); 1395 void jbd2_journal_destroy_checkpoint(journal_t *journal); 1396 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *); 1397 1398 1399 /* 1400 * Triggers 1401 */ 1402 1403 struct jbd2_buffer_trigger_type { 1404 /* 1405 * Fired a the moment data to write to the journal are known to be 1406 * stable - so either at the moment b_frozen_data is created or just 1407 * before a buffer is written to the journal. mapped_data is a mapped 1408 * buffer that is the frozen data for commit. 1409 */ 1410 void (*t_frozen)(struct jbd2_buffer_trigger_type *type, 1411 struct buffer_head *bh, void *mapped_data, 1412 size_t size); 1413 1414 /* 1415 * Fired during journal abort for dirty buffers that will not be 1416 * committed. 1417 */ 1418 void (*t_abort)(struct jbd2_buffer_trigger_type *type, 1419 struct buffer_head *bh); 1420 }; 1421 1422 extern void jbd2_buffer_frozen_trigger(struct journal_head *jh, 1423 void *mapped_data, 1424 struct jbd2_buffer_trigger_type *triggers); 1425 extern void jbd2_buffer_abort_trigger(struct journal_head *jh, 1426 struct jbd2_buffer_trigger_type *triggers); 1427 1428 /* Buffer IO */ 1429 extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction, 1430 struct journal_head *jh_in, 1431 struct buffer_head **bh_out, 1432 sector_t blocknr); 1433 1434 /* Transaction locking */ 1435 extern void __wait_on_journal (journal_t *); 1436 1437 /* Transaction cache support */ 1438 extern void jbd2_journal_destroy_transaction_cache(void); 1439 extern int __init jbd2_journal_init_transaction_cache(void); 1440 extern void jbd2_journal_free_transaction(transaction_t *); 1441 1442 /* 1443 * Journal locking. 1444 * 1445 * We need to lock the journal during transaction state changes so that nobody 1446 * ever tries to take a handle on the running transaction while we are in the 1447 * middle of moving it to the commit phase. j_state_lock does this. 1448 * 1449 * Note that the locking is completely interrupt unsafe. We never touch 1450 * journal structures from interrupts. 1451 */ 1452 1453 static inline handle_t *journal_current_handle(void) 1454 { 1455 return current->journal_info; 1456 } 1457 1458 /* The journaling code user interface: 1459 * 1460 * Create and destroy handles 1461 * Register buffer modifications against the current transaction. 1462 */ 1463 1464 extern handle_t *jbd2_journal_start(journal_t *, int nblocks); 1465 extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks, 1466 int revoke_records, gfp_t gfp_mask, 1467 unsigned int type, unsigned int line_no); 1468 extern int jbd2_journal_restart(handle_t *, int nblocks); 1469 extern int jbd2__journal_restart(handle_t *, int nblocks, 1470 int revoke_records, gfp_t gfp_mask); 1471 extern int jbd2_journal_start_reserved(handle_t *handle, 1472 unsigned int type, unsigned int line_no); 1473 extern void jbd2_journal_free_reserved(handle_t *handle); 1474 extern int jbd2_journal_extend(handle_t *handle, int nblocks, 1475 int revoke_records); 1476 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *); 1477 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *); 1478 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *); 1479 void jbd2_journal_set_triggers(struct buffer_head *, 1480 struct jbd2_buffer_trigger_type *type); 1481 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *); 1482 extern int jbd2_journal_forget (handle_t *, struct buffer_head *); 1483 extern int jbd2_journal_invalidatepage(journal_t *, 1484 struct page *, unsigned int, unsigned int); 1485 extern int jbd2_journal_try_to_free_buffers(journal_t *journal, struct page *page); 1486 extern int jbd2_journal_stop(handle_t *); 1487 extern int jbd2_journal_flush (journal_t *); 1488 extern void jbd2_journal_lock_updates (journal_t *); 1489 extern void jbd2_journal_unlock_updates (journal_t *); 1490 1491 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev, 1492 struct block_device *fs_dev, 1493 unsigned long long start, int len, int bsize); 1494 extern journal_t * jbd2_journal_init_inode (struct inode *); 1495 extern int jbd2_journal_update_format (journal_t *); 1496 extern int jbd2_journal_check_used_features 1497 (journal_t *, unsigned long, unsigned long, unsigned long); 1498 extern int jbd2_journal_check_available_features 1499 (journal_t *, unsigned long, unsigned long, unsigned long); 1500 extern int jbd2_journal_set_features 1501 (journal_t *, unsigned long, unsigned long, unsigned long); 1502 extern void jbd2_journal_clear_features 1503 (journal_t *, unsigned long, unsigned long, unsigned long); 1504 extern int jbd2_journal_load (journal_t *journal); 1505 extern int jbd2_journal_destroy (journal_t *); 1506 extern int jbd2_journal_recover (journal_t *journal); 1507 extern int jbd2_journal_wipe (journal_t *, int); 1508 extern int jbd2_journal_skip_recovery (journal_t *); 1509 extern void jbd2_journal_update_sb_errno(journal_t *); 1510 extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t, 1511 unsigned long, int); 1512 extern void jbd2_journal_abort (journal_t *, int); 1513 extern int jbd2_journal_errno (journal_t *); 1514 extern void jbd2_journal_ack_err (journal_t *); 1515 extern int jbd2_journal_clear_err (journal_t *); 1516 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *); 1517 extern int jbd2_journal_force_commit(journal_t *); 1518 extern int jbd2_journal_force_commit_nested(journal_t *); 1519 extern int jbd2_journal_inode_ranged_write(handle_t *handle, 1520 struct jbd2_inode *inode, loff_t start_byte, 1521 loff_t length); 1522 extern int jbd2_journal_inode_ranged_wait(handle_t *handle, 1523 struct jbd2_inode *inode, loff_t start_byte, 1524 loff_t length); 1525 extern int jbd2_journal_submit_inode_data_buffers( 1526 struct jbd2_inode *jinode); 1527 extern int jbd2_journal_finish_inode_data_buffers( 1528 struct jbd2_inode *jinode); 1529 extern int jbd2_journal_begin_ordered_truncate(journal_t *journal, 1530 struct jbd2_inode *inode, loff_t new_size); 1531 extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode); 1532 extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode); 1533 1534 /* 1535 * journal_head management 1536 */ 1537 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh); 1538 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh); 1539 void jbd2_journal_put_journal_head(struct journal_head *jh); 1540 1541 /* 1542 * handle management 1543 */ 1544 extern struct kmem_cache *jbd2_handle_cache; 1545 1546 static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags) 1547 { 1548 return kmem_cache_zalloc(jbd2_handle_cache, gfp_flags); 1549 } 1550 1551 static inline void jbd2_free_handle(handle_t *handle) 1552 { 1553 kmem_cache_free(jbd2_handle_cache, handle); 1554 } 1555 1556 /* 1557 * jbd2_inode management (optional, for those file systems that want to use 1558 * dynamically allocated jbd2_inode structures) 1559 */ 1560 extern struct kmem_cache *jbd2_inode_cache; 1561 1562 static inline struct jbd2_inode *jbd2_alloc_inode(gfp_t gfp_flags) 1563 { 1564 return kmem_cache_alloc(jbd2_inode_cache, gfp_flags); 1565 } 1566 1567 static inline void jbd2_free_inode(struct jbd2_inode *jinode) 1568 { 1569 kmem_cache_free(jbd2_inode_cache, jinode); 1570 } 1571 1572 /* Primary revoke support */ 1573 #define JOURNAL_REVOKE_DEFAULT_HASH 256 1574 extern int jbd2_journal_init_revoke(journal_t *, int); 1575 extern void jbd2_journal_destroy_revoke_record_cache(void); 1576 extern void jbd2_journal_destroy_revoke_table_cache(void); 1577 extern int __init jbd2_journal_init_revoke_record_cache(void); 1578 extern int __init jbd2_journal_init_revoke_table_cache(void); 1579 1580 extern void jbd2_journal_destroy_revoke(journal_t *); 1581 extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *); 1582 extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *); 1583 extern void jbd2_journal_write_revoke_records(transaction_t *transaction, 1584 struct list_head *log_bufs); 1585 1586 /* Recovery revoke support */ 1587 extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t); 1588 extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t); 1589 extern void jbd2_journal_clear_revoke(journal_t *); 1590 extern void jbd2_journal_switch_revoke_table(journal_t *journal); 1591 extern void jbd2_clear_buffer_revoked_flags(journal_t *journal); 1592 1593 /* 1594 * The log thread user interface: 1595 * 1596 * Request space in the current transaction, and force transaction commit 1597 * transitions on demand. 1598 */ 1599 1600 int jbd2_log_start_commit(journal_t *journal, tid_t tid); 1601 int __jbd2_log_start_commit(journal_t *journal, tid_t tid); 1602 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid); 1603 int jbd2_log_wait_commit(journal_t *journal, tid_t tid); 1604 int jbd2_transaction_committed(journal_t *journal, tid_t tid); 1605 int jbd2_complete_transaction(journal_t *journal, tid_t tid); 1606 int jbd2_log_do_checkpoint(journal_t *journal); 1607 int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid); 1608 1609 void __jbd2_log_wait_for_space(journal_t *journal); 1610 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *); 1611 extern int jbd2_cleanup_journal_tail(journal_t *); 1612 1613 /* Fast commit related APIs */ 1614 int jbd2_fc_init(journal_t *journal, int num_fc_blks); 1615 int jbd2_fc_begin_commit(journal_t *journal, tid_t tid); 1616 int jbd2_fc_end_commit(journal_t *journal); 1617 int jbd2_fc_end_commit_fallback(journal_t *journal, tid_t tid); 1618 int jbd2_fc_get_buf(journal_t *journal, struct buffer_head **bh_out); 1619 int jbd2_submit_inode_data(struct jbd2_inode *jinode); 1620 int jbd2_wait_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1621 int jbd2_fc_wait_bufs(journal_t *journal, int num_blks); 1622 int jbd2_fc_release_bufs(journal_t *journal); 1623 1624 /* 1625 * is_journal_abort 1626 * 1627 * Simple test wrapper function to test the JBD2_ABORT state flag. This 1628 * bit, when set, indicates that we have had a fatal error somewhere, 1629 * either inside the journaling layer or indicated to us by the client 1630 * (eg. ext3), and that we and should not commit any further 1631 * transactions. 1632 */ 1633 1634 static inline int is_journal_aborted(journal_t *journal) 1635 { 1636 return journal->j_flags & JBD2_ABORT; 1637 } 1638 1639 static inline int is_handle_aborted(handle_t *handle) 1640 { 1641 if (handle->h_aborted || !handle->h_transaction) 1642 return 1; 1643 return is_journal_aborted(handle->h_transaction->t_journal); 1644 } 1645 1646 static inline void jbd2_journal_abort_handle(handle_t *handle) 1647 { 1648 handle->h_aborted = 1; 1649 } 1650 1651 #endif /* __KERNEL__ */ 1652 1653 /* Comparison functions for transaction IDs: perform comparisons using 1654 * modulo arithmetic so that they work over sequence number wraps. */ 1655 1656 static inline int tid_gt(tid_t x, tid_t y) 1657 { 1658 int difference = (x - y); 1659 return (difference > 0); 1660 } 1661 1662 static inline int tid_geq(tid_t x, tid_t y) 1663 { 1664 int difference = (x - y); 1665 return (difference >= 0); 1666 } 1667 1668 extern int jbd2_journal_blocks_per_page(struct inode *inode); 1669 extern size_t journal_tag_bytes(journal_t *journal); 1670 1671 static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j) 1672 { 1673 return jbd2_has_feature_csum2(j) || jbd2_has_feature_csum3(j); 1674 } 1675 1676 static inline int jbd2_journal_has_csum_v2or3(journal_t *journal) 1677 { 1678 WARN_ON_ONCE(jbd2_journal_has_csum_v2or3_feature(journal) && 1679 journal->j_chksum_driver == NULL); 1680 1681 return journal->j_chksum_driver != NULL; 1682 } 1683 1684 /* 1685 * Return number of free blocks in the log. Must be called under j_state_lock. 1686 */ 1687 static inline unsigned long jbd2_log_space_left(journal_t *journal) 1688 { 1689 /* Allow for rounding errors */ 1690 long free = journal->j_free - 32; 1691 1692 if (journal->j_committing_transaction) { 1693 free -= atomic_read(&journal-> 1694 j_committing_transaction->t_outstanding_credits); 1695 } 1696 return max_t(long, free, 0); 1697 } 1698 1699 /* 1700 * Definitions which augment the buffer_head layer 1701 */ 1702 1703 /* journaling buffer types */ 1704 #define BJ_None 0 /* Not journaled */ 1705 #define BJ_Metadata 1 /* Normal journaled metadata */ 1706 #define BJ_Forget 2 /* Buffer superseded by this transaction */ 1707 #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */ 1708 #define BJ_Reserved 4 /* Buffer is reserved for access by journal */ 1709 #define BJ_Types 5 1710 1711 extern int jbd_blocks_per_page(struct inode *inode); 1712 1713 /* JBD uses a CRC32 checksum */ 1714 #define JBD_MAX_CHECKSUM_SIZE 4 1715 1716 static inline u32 jbd2_chksum(journal_t *journal, u32 crc, 1717 const void *address, unsigned int length) 1718 { 1719 struct { 1720 struct shash_desc shash; 1721 char ctx[JBD_MAX_CHECKSUM_SIZE]; 1722 } desc; 1723 int err; 1724 1725 BUG_ON(crypto_shash_descsize(journal->j_chksum_driver) > 1726 JBD_MAX_CHECKSUM_SIZE); 1727 1728 desc.shash.tfm = journal->j_chksum_driver; 1729 *(u32 *)desc.ctx = crc; 1730 1731 err = crypto_shash_update(&desc.shash, address, length); 1732 BUG_ON(err); 1733 1734 return *(u32 *)desc.ctx; 1735 } 1736 1737 /* Return most recent uncommitted transaction */ 1738 static inline tid_t jbd2_get_latest_transaction(journal_t *journal) 1739 { 1740 tid_t tid; 1741 1742 read_lock(&journal->j_state_lock); 1743 tid = journal->j_commit_request; 1744 if (journal->j_running_transaction) 1745 tid = journal->j_running_transaction->t_tid; 1746 read_unlock(&journal->j_state_lock); 1747 return tid; 1748 } 1749 1750 static inline int jbd2_handle_buffer_credits(handle_t *handle) 1751 { 1752 journal_t *journal; 1753 1754 if (!handle->h_reserved) 1755 journal = handle->h_transaction->t_journal; 1756 else 1757 journal = handle->h_journal; 1758 1759 return handle->h_total_credits - 1760 DIV_ROUND_UP(handle->h_revoke_credits_requested, 1761 journal->j_revoke_records_per_block); 1762 } 1763 1764 #ifdef __KERNEL__ 1765 1766 #define buffer_trace_init(bh) do {} while (0) 1767 #define print_buffer_fields(bh) do {} while (0) 1768 #define print_buffer_trace(bh) do {} while (0) 1769 #define BUFFER_TRACE(bh, info) do {} while (0) 1770 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0) 1771 #define JBUFFER_TRACE(jh, info) do {} while (0) 1772 1773 #endif /* __KERNEL__ */ 1774 1775 #define EFSBADCRC EBADMSG /* Bad CRC detected */ 1776 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ 1777 1778 #endif /* _LINUX_JBD2_H */ 1779