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 <crypto/hash.h> 31 #endif 32 33 #define journal_oom_retry 1 34 35 /* 36 * Define JBD2_PARANIOD_IOFAIL to cause a kernel BUG() if ext4 finds 37 * certain classes of error which can occur due to failed IOs. Under 38 * normal use we want ext4 to continue after such errors, because 39 * hardware _can_ fail, but for debugging purposes when running tests on 40 * known-good hardware we may want to trap these errors. 41 */ 42 #undef JBD2_PARANOID_IOFAIL 43 44 /* 45 * The default maximum commit age, in seconds. 46 */ 47 #define JBD2_DEFAULT_MAX_COMMIT_AGE 5 48 49 #ifdef CONFIG_JBD2_DEBUG 50 /* 51 * Define JBD2_EXPENSIVE_CHECKING to enable more expensive internal 52 * consistency checks. By default we don't do this unless 53 * CONFIG_JBD2_DEBUG is on. 54 */ 55 #define JBD2_EXPENSIVE_CHECKING 56 extern ushort jbd2_journal_enable_debug; 57 void __jbd2_debug(int level, const char *file, const char *func, 58 unsigned int line, const char *fmt, ...); 59 60 #define jbd_debug(n, fmt, a...) \ 61 __jbd2_debug((n), __FILE__, __func__, __LINE__, (fmt), ##a) 62 #else 63 #define jbd_debug(n, 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 71 #ifdef __KERNEL__ 72 73 /** 74 * typedef handle_t - The handle_t type represents a single atomic update being performed by some process. 75 * 76 * All filesystem modifications made by the process go 77 * through this handle. Recursive operations (such as quota operations) 78 * are gathered into a single update. 79 * 80 * The buffer credits field is used to account for journaled buffers 81 * being modified by the running process. To ensure that there is 82 * enough log space for all outstanding operations, we need to limit the 83 * number of outstanding buffers possible at any time. When the 84 * operation completes, any buffer credits not used are credited back to 85 * the transaction, so that at all times we know how many buffers the 86 * outstanding updates on a transaction might possibly touch. 87 * 88 * This is an opaque datatype. 89 **/ 90 typedef struct jbd2_journal_handle handle_t; /* Atomic operation type */ 91 92 93 /** 94 * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem. 95 * 96 * journal_t is linked to from the fs superblock structure. 97 * 98 * We use the journal_t to keep track of all outstanding transaction 99 * activity on the filesystem, and to manage the state of the log 100 * writing process. 101 * 102 * This is an opaque datatype. 103 **/ 104 typedef struct journal_s journal_t; /* Journal control structure */ 105 #endif 106 107 /* 108 * Internal structures used by the logging mechanism: 109 */ 110 111 #define JBD2_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */ 112 113 /* 114 * On-disk structures 115 */ 116 117 /* 118 * Descriptor block types: 119 */ 120 121 #define JBD2_DESCRIPTOR_BLOCK 1 122 #define JBD2_COMMIT_BLOCK 2 123 #define JBD2_SUPERBLOCK_V1 3 124 #define JBD2_SUPERBLOCK_V2 4 125 #define JBD2_REVOKE_BLOCK 5 126 127 /* 128 * Standard header for all descriptor blocks: 129 */ 130 typedef struct journal_header_s 131 { 132 __be32 h_magic; 133 __be32 h_blocktype; 134 __be32 h_sequence; 135 } journal_header_t; 136 137 /* 138 * Checksum types. 139 */ 140 #define JBD2_CRC32_CHKSUM 1 141 #define JBD2_MD5_CHKSUM 2 142 #define JBD2_SHA1_CHKSUM 3 143 #define JBD2_CRC32C_CHKSUM 4 144 145 #define JBD2_CRC32_CHKSUM_SIZE 4 146 147 #define JBD2_CHECKSUM_BYTES (32 / sizeof(u32)) 148 /* 149 * Commit block header for storing transactional checksums: 150 * 151 * NOTE: If FEATURE_COMPAT_CHECKSUM (checksum v1) is set, the h_chksum* 152 * fields are used to store a checksum of the descriptor and data blocks. 153 * 154 * If FEATURE_INCOMPAT_CSUM_V2 (checksum v2) is set, then the h_chksum 155 * field is used to store crc32c(uuid+commit_block). Each journal metadata 156 * block gets its own checksum, and data block checksums are stored in 157 * journal_block_tag (in the descriptor). The other h_chksum* fields are 158 * not used. 159 * 160 * If FEATURE_INCOMPAT_CSUM_V3 is set, the descriptor block uses 161 * journal_block_tag3_t to store a full 32-bit checksum. Everything else 162 * is the same as v2. 163 * 164 * Checksum v1, v2, and v3 are mutually exclusive features. 165 */ 166 struct commit_header { 167 __be32 h_magic; 168 __be32 h_blocktype; 169 __be32 h_sequence; 170 unsigned char h_chksum_type; 171 unsigned char h_chksum_size; 172 unsigned char h_padding[2]; 173 __be32 h_chksum[JBD2_CHECKSUM_BYTES]; 174 __be64 h_commit_sec; 175 __be32 h_commit_nsec; 176 }; 177 178 /* 179 * The block tag: used to describe a single buffer in the journal. 180 * t_blocknr_high is only used if INCOMPAT_64BIT is set, so this 181 * raw struct shouldn't be used for pointer math or sizeof() - use 182 * journal_tag_bytes(journal) instead to compute this. 183 */ 184 typedef struct journal_block_tag3_s 185 { 186 __be32 t_blocknr; /* The on-disk block number */ 187 __be32 t_flags; /* See below */ 188 __be32 t_blocknr_high; /* most-significant high 32bits. */ 189 __be32 t_checksum; /* crc32c(uuid+seq+block) */ 190 } journal_block_tag3_t; 191 192 typedef struct journal_block_tag_s 193 { 194 __be32 t_blocknr; /* The on-disk block number */ 195 __be16 t_checksum; /* truncated crc32c(uuid+seq+block) */ 196 __be16 t_flags; /* See below */ 197 __be32 t_blocknr_high; /* most-significant high 32bits. */ 198 } journal_block_tag_t; 199 200 /* Tail of descriptor or revoke block, for checksumming */ 201 struct jbd2_journal_block_tail { 202 __be32 t_checksum; /* crc32c(uuid+descr_block) */ 203 }; 204 205 /* 206 * The revoke descriptor: used on disk to describe a series of blocks to 207 * be revoked from the log 208 */ 209 typedef struct jbd2_journal_revoke_header_s 210 { 211 journal_header_t r_header; 212 __be32 r_count; /* Count of bytes used in the block */ 213 } jbd2_journal_revoke_header_t; 214 215 /* Definitions for the journal tag flags word: */ 216 #define JBD2_FLAG_ESCAPE 1 /* on-disk block is escaped */ 217 #define JBD2_FLAG_SAME_UUID 2 /* block has same uuid as previous */ 218 #define JBD2_FLAG_DELETED 4 /* block deleted by this transaction */ 219 #define JBD2_FLAG_LAST_TAG 8 /* last tag in this descriptor block */ 220 221 222 /* 223 * The journal superblock. All fields are in big-endian byte order. 224 */ 225 typedef struct journal_superblock_s 226 { 227 /* 0x0000 */ 228 journal_header_t s_header; 229 230 /* 0x000C */ 231 /* Static information describing the journal */ 232 __be32 s_blocksize; /* journal device blocksize */ 233 __be32 s_maxlen; /* total blocks in journal file */ 234 __be32 s_first; /* first block of log information */ 235 236 /* 0x0018 */ 237 /* Dynamic information describing the current state of the log */ 238 __be32 s_sequence; /* first commit ID expected in log */ 239 __be32 s_start; /* blocknr of start of log */ 240 241 /* 0x0020 */ 242 /* Error value, as set by jbd2_journal_abort(). */ 243 __be32 s_errno; 244 245 /* 0x0024 */ 246 /* Remaining fields are only valid in a version-2 superblock */ 247 __be32 s_feature_compat; /* compatible feature set */ 248 __be32 s_feature_incompat; /* incompatible feature set */ 249 __be32 s_feature_ro_compat; /* readonly-compatible feature set */ 250 /* 0x0030 */ 251 __u8 s_uuid[16]; /* 128-bit uuid for journal */ 252 253 /* 0x0040 */ 254 __be32 s_nr_users; /* Nr of filesystems sharing log */ 255 256 __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/ 257 258 /* 0x0048 */ 259 __be32 s_max_transaction; /* Limit of journal blocks per trans.*/ 260 __be32 s_max_trans_data; /* Limit of data blocks per trans. */ 261 262 /* 0x0050 */ 263 __u8 s_checksum_type; /* checksum type */ 264 __u8 s_padding2[3]; 265 __u32 s_padding[42]; 266 __be32 s_checksum; /* crc32c(superblock) */ 267 268 /* 0x0100 */ 269 __u8 s_users[16*48]; /* ids of all fs'es sharing the log */ 270 /* 0x0400 */ 271 } journal_superblock_t; 272 273 /* Use the jbd2_{has,set,clear}_feature_* helpers; these will be removed */ 274 #define JBD2_HAS_COMPAT_FEATURE(j,mask) \ 275 ((j)->j_format_version >= 2 && \ 276 ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask)))) 277 #define JBD2_HAS_RO_COMPAT_FEATURE(j,mask) \ 278 ((j)->j_format_version >= 2 && \ 279 ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask)))) 280 #define JBD2_HAS_INCOMPAT_FEATURE(j,mask) \ 281 ((j)->j_format_version >= 2 && \ 282 ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask)))) 283 284 #define JBD2_FEATURE_COMPAT_CHECKSUM 0x00000001 285 286 #define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001 287 #define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002 288 #define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT 0x00000004 289 #define JBD2_FEATURE_INCOMPAT_CSUM_V2 0x00000008 290 #define JBD2_FEATURE_INCOMPAT_CSUM_V3 0x00000010 291 292 /* See "journal feature predicate functions" below */ 293 294 /* Features known to this kernel version: */ 295 #define JBD2_KNOWN_COMPAT_FEATURES JBD2_FEATURE_COMPAT_CHECKSUM 296 #define JBD2_KNOWN_ROCOMPAT_FEATURES 0 297 #define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \ 298 JBD2_FEATURE_INCOMPAT_64BIT | \ 299 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | \ 300 JBD2_FEATURE_INCOMPAT_CSUM_V2 | \ 301 JBD2_FEATURE_INCOMPAT_CSUM_V3) 302 303 #ifdef __KERNEL__ 304 305 #include <linux/fs.h> 306 #include <linux/sched.h> 307 308 enum jbd_state_bits { 309 BH_JBD /* Has an attached ext3 journal_head */ 310 = BH_PrivateStart, 311 BH_JWrite, /* Being written to log (@@@ DEBUGGING) */ 312 BH_Freed, /* Has been freed (truncated) */ 313 BH_Revoked, /* Has been revoked from the log */ 314 BH_RevokeValid, /* Revoked flag is valid */ 315 BH_JBDDirty, /* Is dirty but journaled */ 316 BH_State, /* Pins most journal_head state */ 317 BH_JournalHead, /* Pins bh->b_private and jh->b_bh */ 318 BH_Shadow, /* IO on shadow buffer is running */ 319 BH_Verified, /* Metadata block has been verified ok */ 320 BH_JBDPrivateStart, /* First bit available for private use by FS */ 321 }; 322 323 BUFFER_FNS(JBD, jbd) 324 BUFFER_FNS(JWrite, jwrite) 325 BUFFER_FNS(JBDDirty, jbddirty) 326 TAS_BUFFER_FNS(JBDDirty, jbddirty) 327 BUFFER_FNS(Revoked, revoked) 328 TAS_BUFFER_FNS(Revoked, revoked) 329 BUFFER_FNS(RevokeValid, revokevalid) 330 TAS_BUFFER_FNS(RevokeValid, revokevalid) 331 BUFFER_FNS(Freed, freed) 332 BUFFER_FNS(Shadow, shadow) 333 BUFFER_FNS(Verified, verified) 334 335 static inline struct buffer_head *jh2bh(struct journal_head *jh) 336 { 337 return jh->b_bh; 338 } 339 340 static inline struct journal_head *bh2jh(struct buffer_head *bh) 341 { 342 return bh->b_private; 343 } 344 345 static inline void jbd_lock_bh_state(struct buffer_head *bh) 346 { 347 bit_spin_lock(BH_State, &bh->b_state); 348 } 349 350 static inline int jbd_trylock_bh_state(struct buffer_head *bh) 351 { 352 return bit_spin_trylock(BH_State, &bh->b_state); 353 } 354 355 static inline int jbd_is_locked_bh_state(struct buffer_head *bh) 356 { 357 return bit_spin_is_locked(BH_State, &bh->b_state); 358 } 359 360 static inline void jbd_unlock_bh_state(struct buffer_head *bh) 361 { 362 bit_spin_unlock(BH_State, &bh->b_state); 363 } 364 365 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh) 366 { 367 bit_spin_lock(BH_JournalHead, &bh->b_state); 368 } 369 370 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh) 371 { 372 bit_spin_unlock(BH_JournalHead, &bh->b_state); 373 } 374 375 #define J_ASSERT(assert) BUG_ON(!(assert)) 376 377 #define J_ASSERT_BH(bh, expr) J_ASSERT(expr) 378 #define J_ASSERT_JH(jh, expr) J_ASSERT(expr) 379 380 #if defined(JBD2_PARANOID_IOFAIL) 381 #define J_EXPECT(expr, why...) J_ASSERT(expr) 382 #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr) 383 #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr) 384 #else 385 #define __journal_expect(expr, why...) \ 386 ({ \ 387 int val = (expr); \ 388 if (!val) { \ 389 printk(KERN_ERR \ 390 "JBD2 unexpected failure: %s: %s;\n", \ 391 __func__, #expr); \ 392 printk(KERN_ERR why "\n"); \ 393 } \ 394 val; \ 395 }) 396 #define J_EXPECT(expr, why...) __journal_expect(expr, ## why) 397 #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why) 398 #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why) 399 #endif 400 401 /* Flags in jbd_inode->i_flags */ 402 #define __JI_COMMIT_RUNNING 0 403 #define __JI_WRITE_DATA 1 404 #define __JI_WAIT_DATA 2 405 406 /* 407 * Commit of the inode data in progress. We use this flag to protect us from 408 * concurrent deletion of inode. We cannot use reference to inode for this 409 * since we cannot afford doing last iput() on behalf of kjournald 410 */ 411 #define JI_COMMIT_RUNNING (1 << __JI_COMMIT_RUNNING) 412 /* Write allocated dirty buffers in this inode before commit */ 413 #define JI_WRITE_DATA (1 << __JI_WRITE_DATA) 414 /* Wait for outstanding data writes for this inode before commit */ 415 #define JI_WAIT_DATA (1 << __JI_WAIT_DATA) 416 417 /** 418 * struct jbd_inode - The jbd_inode type is the structure linking inodes in 419 * ordered mode present in a transaction so that we can sync them during commit. 420 */ 421 struct jbd2_inode { 422 /** 423 * @i_transaction: 424 * 425 * Which transaction does this inode belong to? Either the running 426 * transaction or the committing one. [j_list_lock] 427 */ 428 transaction_t *i_transaction; 429 430 /** 431 * @i_next_transaction: 432 * 433 * Pointer to the running transaction modifying inode's data in case 434 * there is already a committing transaction touching it. [j_list_lock] 435 */ 436 transaction_t *i_next_transaction; 437 438 /** 439 * @i_list: List of inodes in the i_transaction [j_list_lock] 440 */ 441 struct list_head i_list; 442 443 /** 444 * @i_vfs_inode: 445 * 446 * VFS inode this inode belongs to [constant for lifetime of structure] 447 */ 448 struct inode *i_vfs_inode; 449 450 /** 451 * @i_flags: Flags of inode [j_list_lock] 452 */ 453 unsigned long i_flags; 454 455 /** 456 * @i_dirty_start: 457 * 458 * Offset in bytes where the dirty range for this inode starts. 459 * [j_list_lock] 460 */ 461 loff_t i_dirty_start; 462 463 /** 464 * @i_dirty_end: 465 * 466 * Inclusive offset in bytes where the dirty range for this inode 467 * ends. [j_list_lock] 468 */ 469 loff_t i_dirty_end; 470 }; 471 472 struct jbd2_revoke_table_s; 473 474 /** 475 * struct handle_s - The handle_s type is the concrete type associated with 476 * handle_t. 477 * @h_transaction: Which compound transaction is this update a part of? 478 * @h_journal: Which journal handle belongs to - used iff h_reserved set. 479 * @h_rsv_handle: Handle reserved for finishing the logical operation. 480 * @h_buffer_credits: Number of remaining buffers we are allowed to dirty. 481 * @h_ref: Reference count on this handle. 482 * @h_err: Field for caller's use to track errors through large fs operations. 483 * @h_sync: Flag for sync-on-close. 484 * @h_jdata: Flag to force data journaling. 485 * @h_reserved: Flag for handle for reserved credits. 486 * @h_aborted: Flag indicating fatal error on handle. 487 * @h_type: For handle statistics. 488 * @h_line_no: For handle statistics. 489 * @h_start_jiffies: Handle Start time. 490 * @h_requested_credits: Holds @h_buffer_credits after handle is started. 491 * @saved_alloc_context: Saved context while transaction is open. 492 **/ 493 494 /* Docbook can't yet cope with the bit fields, but will leave the documentation 495 * in so it can be fixed later. 496 */ 497 498 struct jbd2_journal_handle 499 { 500 union { 501 transaction_t *h_transaction; 502 /* Which journal handle belongs to - used iff h_reserved set */ 503 journal_t *h_journal; 504 }; 505 506 handle_t *h_rsv_handle; 507 int h_buffer_credits; 508 int h_ref; 509 int h_err; 510 511 /* Flags [no locking] */ 512 unsigned int h_sync: 1; 513 unsigned int h_jdata: 1; 514 unsigned int h_reserved: 1; 515 unsigned int h_aborted: 1; 516 unsigned int h_type: 8; 517 unsigned int h_line_no: 16; 518 519 unsigned long h_start_jiffies; 520 unsigned int h_requested_credits; 521 522 unsigned int saved_alloc_context; 523 }; 524 525 526 /* 527 * Some stats for checkpoint phase 528 */ 529 struct transaction_chp_stats_s { 530 unsigned long cs_chp_time; 531 __u32 cs_forced_to_close; 532 __u32 cs_written; 533 __u32 cs_dropped; 534 }; 535 536 /* The transaction_t type is the guts of the journaling mechanism. It 537 * tracks a compound transaction through its various states: 538 * 539 * RUNNING: accepting new updates 540 * LOCKED: Updates still running but we don't accept new ones 541 * RUNDOWN: Updates are tidying up but have finished requesting 542 * new buffers to modify (state not used for now) 543 * FLUSH: All updates complete, but we are still writing to disk 544 * COMMIT: All data on disk, writing commit record 545 * FINISHED: We still have to keep the transaction for checkpointing. 546 * 547 * The transaction keeps track of all of the buffers modified by a 548 * running transaction, and all of the buffers committed but not yet 549 * flushed to home for finished transactions. 550 */ 551 552 /* 553 * Lock ranking: 554 * 555 * j_list_lock 556 * ->jbd_lock_bh_journal_head() (This is "innermost") 557 * 558 * j_state_lock 559 * ->jbd_lock_bh_state() 560 * 561 * jbd_lock_bh_state() 562 * ->j_list_lock 563 * 564 * j_state_lock 565 * ->t_handle_lock 566 * 567 * j_state_lock 568 * ->j_list_lock (journal_unmap_buffer) 569 * 570 */ 571 572 struct transaction_s 573 { 574 /* Pointer to the journal for this transaction. [no locking] */ 575 journal_t *t_journal; 576 577 /* Sequence number for this transaction [no locking] */ 578 tid_t t_tid; 579 580 /* 581 * Transaction's current state 582 * [no locking - only kjournald2 alters this] 583 * [j_list_lock] guards transition of a transaction into T_FINISHED 584 * state and subsequent call of __jbd2_journal_drop_transaction() 585 * FIXME: needs barriers 586 * KLUDGE: [use j_state_lock] 587 */ 588 enum { 589 T_RUNNING, 590 T_LOCKED, 591 T_SWITCH, 592 T_FLUSH, 593 T_COMMIT, 594 T_COMMIT_DFLUSH, 595 T_COMMIT_JFLUSH, 596 T_COMMIT_CALLBACK, 597 T_FINISHED 598 } t_state; 599 600 /* 601 * Where in the log does this transaction's commit start? [no locking] 602 */ 603 unsigned long t_log_start; 604 605 /* Number of buffers on the t_buffers list [j_list_lock] */ 606 int t_nr_buffers; 607 608 /* 609 * Doubly-linked circular list of all buffers reserved but not yet 610 * modified by this transaction [j_list_lock] 611 */ 612 struct journal_head *t_reserved_list; 613 614 /* 615 * Doubly-linked circular list of all metadata buffers owned by this 616 * transaction [j_list_lock] 617 */ 618 struct journal_head *t_buffers; 619 620 /* 621 * Doubly-linked circular list of all forget buffers (superseded 622 * buffers which we can un-checkpoint once this transaction commits) 623 * [j_list_lock] 624 */ 625 struct journal_head *t_forget; 626 627 /* 628 * Doubly-linked circular list of all buffers still to be flushed before 629 * this transaction can be checkpointed. [j_list_lock] 630 */ 631 struct journal_head *t_checkpoint_list; 632 633 /* 634 * Doubly-linked circular list of all buffers submitted for IO while 635 * checkpointing. [j_list_lock] 636 */ 637 struct journal_head *t_checkpoint_io_list; 638 639 /* 640 * Doubly-linked circular list of metadata buffers being shadowed by log 641 * IO. The IO buffers on the iobuf list and the shadow buffers on this 642 * list match each other one for one at all times. [j_list_lock] 643 */ 644 struct journal_head *t_shadow_list; 645 646 /* 647 * List of inodes whose data we've modified in data=ordered mode. 648 * [j_list_lock] 649 */ 650 struct list_head t_inode_list; 651 652 /* 653 * Protects info related to handles 654 */ 655 spinlock_t t_handle_lock; 656 657 /* 658 * Longest time some handle had to wait for running transaction 659 */ 660 unsigned long t_max_wait; 661 662 /* 663 * When transaction started 664 */ 665 unsigned long t_start; 666 667 /* 668 * When commit was requested 669 */ 670 unsigned long t_requested; 671 672 /* 673 * Checkpointing stats [j_checkpoint_sem] 674 */ 675 struct transaction_chp_stats_s t_chp_stats; 676 677 /* 678 * Number of outstanding updates running on this transaction 679 * [none] 680 */ 681 atomic_t t_updates; 682 683 /* 684 * Number of buffers reserved for use by all handles in this transaction 685 * handle but not yet modified. [none] 686 */ 687 atomic_t t_outstanding_credits; 688 689 /* 690 * Forward and backward links for the circular list of all transactions 691 * awaiting checkpoint. [j_list_lock] 692 */ 693 transaction_t *t_cpnext, *t_cpprev; 694 695 /* 696 * When will the transaction expire (become due for commit), in jiffies? 697 * [no locking] 698 */ 699 unsigned long t_expires; 700 701 /* 702 * When this transaction started, in nanoseconds [no locking] 703 */ 704 ktime_t t_start_time; 705 706 /* 707 * How many handles used this transaction? [none] 708 */ 709 atomic_t t_handle_count; 710 711 /* 712 * This transaction is being forced and some process is 713 * waiting for it to finish. 714 */ 715 unsigned int t_synchronous_commit:1; 716 717 /* Disk flush needs to be sent to fs partition [no locking] */ 718 int t_need_data_flush; 719 720 /* 721 * For use by the filesystem to store fs-specific data 722 * structures associated with the transaction 723 */ 724 struct list_head t_private_list; 725 }; 726 727 struct transaction_run_stats_s { 728 unsigned long rs_wait; 729 unsigned long rs_request_delay; 730 unsigned long rs_running; 731 unsigned long rs_locked; 732 unsigned long rs_flushing; 733 unsigned long rs_logging; 734 735 __u32 rs_handle_count; 736 __u32 rs_blocks; 737 __u32 rs_blocks_logged; 738 }; 739 740 struct transaction_stats_s { 741 unsigned long ts_tid; 742 unsigned long ts_requested; 743 struct transaction_run_stats_s run; 744 }; 745 746 static inline unsigned long 747 jbd2_time_diff(unsigned long start, unsigned long end) 748 { 749 if (end >= start) 750 return end - start; 751 752 return end + (MAX_JIFFY_OFFSET - start); 753 } 754 755 #define JBD2_NR_BATCH 64 756 757 /** 758 * struct journal_s - The journal_s type is the concrete type associated with 759 * journal_t. 760 */ 761 struct journal_s 762 { 763 /** 764 * @j_flags: General journaling state flags [j_state_lock] 765 */ 766 unsigned long j_flags; 767 768 /** 769 * @j_errno: 770 * 771 * Is there an outstanding uncleared error on the journal (from a prior 772 * abort)? [j_state_lock] 773 */ 774 int j_errno; 775 776 /** 777 * @j_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_format_version: Version of the superblock format. 788 */ 789 int j_format_version; 790 791 /** 792 * @j_state_lock: Protect the various scalars in the journal. 793 */ 794 rwlock_t j_state_lock; 795 796 /** 797 * @j_barrier_count: 798 * 799 * Number of processes waiting to create a barrier lock [j_state_lock] 800 */ 801 int j_barrier_count; 802 803 /** 804 * @j_barrier: The barrier lock itself. 805 */ 806 struct mutex j_barrier; 807 808 /** 809 * @j_running_transaction: 810 * 811 * Transactions: The current running transaction... 812 * [j_state_lock] [caller holding open handle] 813 */ 814 transaction_t *j_running_transaction; 815 816 /** 817 * @j_committing_transaction: 818 * 819 * the transaction we are pushing to disk 820 * [j_state_lock] [caller holding open handle] 821 */ 822 transaction_t *j_committing_transaction; 823 824 /** 825 * @j_checkpoint_transactions: 826 * 827 * ... and a linked circular list of all transactions waiting for 828 * checkpointing. [j_list_lock] 829 */ 830 transaction_t *j_checkpoint_transactions; 831 832 /** 833 * @j_wait_transaction_locked: 834 * 835 * Wait queue for waiting for a locked transaction to start committing, 836 * or for a barrier lock to be released. 837 */ 838 wait_queue_head_t j_wait_transaction_locked; 839 840 /** 841 * @j_wait_done_commit: Wait queue for waiting for commit to complete. 842 */ 843 wait_queue_head_t j_wait_done_commit; 844 845 /** 846 * @j_wait_commit: Wait queue to trigger commit. 847 */ 848 wait_queue_head_t j_wait_commit; 849 850 /** 851 * @j_wait_updates: Wait queue to wait for updates to complete. 852 */ 853 wait_queue_head_t j_wait_updates; 854 855 /** 856 * @j_wait_reserved: 857 * 858 * Wait queue to wait for reserved buffer credits to drop. 859 */ 860 wait_queue_head_t j_wait_reserved; 861 862 /** 863 * @j_checkpoint_mutex: 864 * 865 * Semaphore for locking against concurrent checkpoints. 866 */ 867 struct mutex j_checkpoint_mutex; 868 869 /** 870 * @j_chkpt_bhs: 871 * 872 * List of buffer heads used by the checkpoint routine. This 873 * was moved from jbd2_log_do_checkpoint() to reduce stack 874 * usage. Access to this array is controlled by the 875 * @j_checkpoint_mutex. [j_checkpoint_mutex] 876 */ 877 struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH]; 878 879 /** 880 * @j_head: 881 * 882 * Journal head: identifies the first unused block in the journal. 883 * [j_state_lock] 884 */ 885 unsigned long j_head; 886 887 /** 888 * @j_tail: 889 * 890 * Journal tail: identifies the oldest still-used block in the journal. 891 * [j_state_lock] 892 */ 893 unsigned long j_tail; 894 895 /** 896 * @j_free: 897 * 898 * Journal free: how many free blocks are there in the journal? 899 * [j_state_lock] 900 */ 901 unsigned long j_free; 902 903 /** 904 * @j_first: 905 * 906 * The block number of the first usable block in the journal 907 * [j_state_lock]. 908 */ 909 unsigned long j_first; 910 911 /** 912 * @j_last: 913 * 914 * The block number one beyond the last usable block in the journal 915 * [j_state_lock]. 916 */ 917 unsigned long j_last; 918 919 /** 920 * @j_dev: Device where we store the journal. 921 */ 922 struct block_device *j_dev; 923 924 /** 925 * @j_blocksize: Block size for the location where we store the journal. 926 */ 927 int j_blocksize; 928 929 /** 930 * @j_blk_offset: 931 * 932 * Starting block offset into the device where we store the journal. 933 */ 934 unsigned long long j_blk_offset; 935 936 /** 937 * @j_devname: Journal device name. 938 */ 939 char j_devname[BDEVNAME_SIZE+24]; 940 941 /** 942 * @j_fs_dev: 943 * 944 * Device which holds the client fs. For internal journal this will be 945 * equal to j_dev. 946 */ 947 struct block_device *j_fs_dev; 948 949 /** 950 * @j_maxlen: Total maximum capacity of the journal region on disk. 951 */ 952 unsigned int j_maxlen; 953 954 /** 955 * @j_reserved_credits: 956 * 957 * Number of buffers reserved from the running transaction. 958 */ 959 atomic_t j_reserved_credits; 960 961 /** 962 * @j_list_lock: Protects the buffer lists and internal buffer state. 963 */ 964 spinlock_t j_list_lock; 965 966 /** 967 * @j_inode: 968 * 969 * Optional inode where we store the journal. If present, all 970 * journal block numbers are mapped into this inode via bmap(). 971 */ 972 struct inode *j_inode; 973 974 /** 975 * @j_tail_sequence: 976 * 977 * Sequence number of the oldest transaction in the log [j_state_lock] 978 */ 979 tid_t j_tail_sequence; 980 981 /** 982 * @j_transaction_sequence: 983 * 984 * Sequence number of the next transaction to grant [j_state_lock] 985 */ 986 tid_t j_transaction_sequence; 987 988 /** 989 * @j_commit_sequence: 990 * 991 * Sequence number of the most recently committed transaction 992 * [j_state_lock]. 993 */ 994 tid_t j_commit_sequence; 995 996 /** 997 * @j_commit_request: 998 * 999 * Sequence number of the most recent transaction wanting commit 1000 * [j_state_lock] 1001 */ 1002 tid_t j_commit_request; 1003 1004 /** 1005 * @j_uuid: 1006 * 1007 * Journal uuid: identifies the object (filesystem, LVM volume etc) 1008 * backed by this journal. This will eventually be replaced by an array 1009 * of uuids, allowing us to index multiple devices within a single 1010 * journal and to perform atomic updates across them. 1011 */ 1012 __u8 j_uuid[16]; 1013 1014 /** 1015 * @j_task: Pointer to the current commit thread for this journal. 1016 */ 1017 struct task_struct *j_task; 1018 1019 /** 1020 * @j_max_transaction_buffers: 1021 * 1022 * Maximum number of metadata buffers to allow in a single compound 1023 * commit transaction. 1024 */ 1025 int j_max_transaction_buffers; 1026 1027 /** 1028 * @j_commit_interval: 1029 * 1030 * What is the maximum transaction lifetime before we begin a commit? 1031 */ 1032 unsigned long j_commit_interval; 1033 1034 /** 1035 * @j_commit_timer: The timer used to wakeup the commit thread. 1036 */ 1037 struct timer_list j_commit_timer; 1038 1039 /** 1040 * @j_revoke_lock: Protect the revoke table. 1041 */ 1042 spinlock_t j_revoke_lock; 1043 1044 /** 1045 * @j_revoke: 1046 * 1047 * The revoke table - maintains the list of revoked blocks in the 1048 * current transaction. 1049 */ 1050 struct jbd2_revoke_table_s *j_revoke; 1051 1052 /** 1053 * @j_revoke_table: Alternate revoke tables for j_revoke. 1054 */ 1055 struct jbd2_revoke_table_s *j_revoke_table[2]; 1056 1057 /** 1058 * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction. 1059 */ 1060 struct buffer_head **j_wbuf; 1061 1062 /** 1063 * @j_wbufsize: 1064 * 1065 * Size of @j_wbuf array. 1066 */ 1067 int j_wbufsize; 1068 1069 /** 1070 * @j_last_sync_writer: 1071 * 1072 * The pid of the last person to run a synchronous operation 1073 * through the journal. 1074 */ 1075 pid_t j_last_sync_writer; 1076 1077 /** 1078 * @j_average_commit_time: 1079 * 1080 * The average amount of time in nanoseconds it takes to commit a 1081 * transaction to disk. [j_state_lock] 1082 */ 1083 u64 j_average_commit_time; 1084 1085 /** 1086 * @j_min_batch_time: 1087 * 1088 * Minimum time that we should wait for additional filesystem operations 1089 * to get batched into a synchronous handle in microseconds. 1090 */ 1091 u32 j_min_batch_time; 1092 1093 /** 1094 * @j_max_batch_time: 1095 * 1096 * Maximum time that we should wait for additional filesystem operations 1097 * to get batched into a synchronous handle in microseconds. 1098 */ 1099 u32 j_max_batch_time; 1100 1101 /** 1102 * @j_commit_callback: 1103 * 1104 * This function is called when a transaction is closed. 1105 */ 1106 void (*j_commit_callback)(journal_t *, 1107 transaction_t *); 1108 1109 /* 1110 * Journal statistics 1111 */ 1112 1113 /** 1114 * @j_history_lock: Protect the transactions statistics history. 1115 */ 1116 spinlock_t j_history_lock; 1117 1118 /** 1119 * @j_proc_entry: procfs entry for the jbd statistics directory. 1120 */ 1121 struct proc_dir_entry *j_proc_entry; 1122 1123 /** 1124 * @j_stats: Overall statistics. 1125 */ 1126 struct transaction_stats_s j_stats; 1127 1128 /** 1129 * @j_failed_commit: Failed journal commit ID. 1130 */ 1131 unsigned int j_failed_commit; 1132 1133 /** 1134 * @j_private: 1135 * 1136 * An opaque pointer to fs-private information. ext3 puts its 1137 * superblock pointer here. 1138 */ 1139 void *j_private; 1140 1141 /** 1142 * @j_chksum_driver: 1143 * 1144 * Reference to checksum algorithm driver via cryptoapi. 1145 */ 1146 struct crypto_shash *j_chksum_driver; 1147 1148 /** 1149 * @j_csum_seed: 1150 * 1151 * Precomputed journal UUID checksum for seeding other checksums. 1152 */ 1153 __u32 j_csum_seed; 1154 1155 #ifdef CONFIG_DEBUG_LOCK_ALLOC 1156 /** 1157 * @j_trans_commit_map: 1158 * 1159 * Lockdep entity to track transaction commit dependencies. Handles 1160 * hold this "lock" for read, when we wait for commit, we acquire the 1161 * "lock" for writing. This matches the properties of jbd2 journalling 1162 * where the running transaction has to wait for all handles to be 1163 * dropped to commit that transaction and also acquiring a handle may 1164 * require transaction commit to finish. 1165 */ 1166 struct lockdep_map j_trans_commit_map; 1167 #endif 1168 }; 1169 1170 #define jbd2_might_wait_for_commit(j) \ 1171 do { \ 1172 rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \ 1173 rwsem_release(&j->j_trans_commit_map, 1, _THIS_IP_); \ 1174 } while (0) 1175 1176 /* journal feature predicate functions */ 1177 #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \ 1178 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1179 { \ 1180 return ((j)->j_format_version >= 2 && \ 1181 ((j)->j_superblock->s_feature_compat & \ 1182 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \ 1183 } \ 1184 static inline void jbd2_set_feature_##name(journal_t *j) \ 1185 { \ 1186 (j)->j_superblock->s_feature_compat |= \ 1187 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1188 } \ 1189 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1190 { \ 1191 (j)->j_superblock->s_feature_compat &= \ 1192 ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1193 } 1194 1195 #define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \ 1196 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1197 { \ 1198 return ((j)->j_format_version >= 2 && \ 1199 ((j)->j_superblock->s_feature_ro_compat & \ 1200 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \ 1201 } \ 1202 static inline void jbd2_set_feature_##name(journal_t *j) \ 1203 { \ 1204 (j)->j_superblock->s_feature_ro_compat |= \ 1205 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1206 } \ 1207 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1208 { \ 1209 (j)->j_superblock->s_feature_ro_compat &= \ 1210 ~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1211 } 1212 1213 #define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \ 1214 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1215 { \ 1216 return ((j)->j_format_version >= 2 && \ 1217 ((j)->j_superblock->s_feature_incompat & \ 1218 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \ 1219 } \ 1220 static inline void jbd2_set_feature_##name(journal_t *j) \ 1221 { \ 1222 (j)->j_superblock->s_feature_incompat |= \ 1223 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1224 } \ 1225 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1226 { \ 1227 (j)->j_superblock->s_feature_incompat &= \ 1228 ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1229 } 1230 1231 JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM) 1232 1233 JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE) 1234 JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT) 1235 JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT) 1236 JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2) 1237 JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3) 1238 1239 /* 1240 * Journal flag definitions 1241 */ 1242 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */ 1243 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */ 1244 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */ 1245 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */ 1246 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */ 1247 #define JBD2_BARRIER 0x020 /* Use IDE barriers */ 1248 #define JBD2_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file 1249 * data write error in ordered 1250 * mode */ 1251 #define JBD2_REC_ERR 0x080 /* The errno in the sb has been recorded */ 1252 1253 /* 1254 * Function declarations for the journaling transaction and buffer 1255 * management 1256 */ 1257 1258 /* Filing buffers */ 1259 extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *); 1260 extern void __jbd2_journal_refile_buffer(struct journal_head *); 1261 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *); 1262 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1263 extern void __journal_free_buffer(struct journal_head *bh); 1264 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1265 extern void __journal_clean_data_list(transaction_t *transaction); 1266 static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh) 1267 { 1268 list_add_tail(&bh->b_assoc_buffers, head); 1269 } 1270 static inline void jbd2_unfile_log_bh(struct buffer_head *bh) 1271 { 1272 list_del_init(&bh->b_assoc_buffers); 1273 } 1274 1275 /* Log buffer allocation */ 1276 struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int); 1277 void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *); 1278 int jbd2_journal_next_log_block(journal_t *, unsigned long long *); 1279 int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, 1280 unsigned long *block); 1281 int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1282 void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1283 1284 /* Commit management */ 1285 extern void jbd2_journal_commit_transaction(journal_t *); 1286 1287 /* Checkpoint list management */ 1288 void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy); 1289 int __jbd2_journal_remove_checkpoint(struct journal_head *); 1290 void jbd2_journal_destroy_checkpoint(journal_t *journal); 1291 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *); 1292 1293 1294 /* 1295 * Triggers 1296 */ 1297 1298 struct jbd2_buffer_trigger_type { 1299 /* 1300 * Fired a the moment data to write to the journal are known to be 1301 * stable - so either at the moment b_frozen_data is created or just 1302 * before a buffer is written to the journal. mapped_data is a mapped 1303 * buffer that is the frozen data for commit. 1304 */ 1305 void (*t_frozen)(struct jbd2_buffer_trigger_type *type, 1306 struct buffer_head *bh, void *mapped_data, 1307 size_t size); 1308 1309 /* 1310 * Fired during journal abort for dirty buffers that will not be 1311 * committed. 1312 */ 1313 void (*t_abort)(struct jbd2_buffer_trigger_type *type, 1314 struct buffer_head *bh); 1315 }; 1316 1317 extern void jbd2_buffer_frozen_trigger(struct journal_head *jh, 1318 void *mapped_data, 1319 struct jbd2_buffer_trigger_type *triggers); 1320 extern void jbd2_buffer_abort_trigger(struct journal_head *jh, 1321 struct jbd2_buffer_trigger_type *triggers); 1322 1323 /* Buffer IO */ 1324 extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction, 1325 struct journal_head *jh_in, 1326 struct buffer_head **bh_out, 1327 sector_t blocknr); 1328 1329 /* Transaction locking */ 1330 extern void __wait_on_journal (journal_t *); 1331 1332 /* Transaction cache support */ 1333 extern void jbd2_journal_destroy_transaction_cache(void); 1334 extern int __init jbd2_journal_init_transaction_cache(void); 1335 extern void jbd2_journal_free_transaction(transaction_t *); 1336 1337 /* 1338 * Journal locking. 1339 * 1340 * We need to lock the journal during transaction state changes so that nobody 1341 * ever tries to take a handle on the running transaction while we are in the 1342 * middle of moving it to the commit phase. j_state_lock does this. 1343 * 1344 * Note that the locking is completely interrupt unsafe. We never touch 1345 * journal structures from interrupts. 1346 */ 1347 1348 static inline handle_t *journal_current_handle(void) 1349 { 1350 return current->journal_info; 1351 } 1352 1353 /* The journaling code user interface: 1354 * 1355 * Create and destroy handles 1356 * Register buffer modifications against the current transaction. 1357 */ 1358 1359 extern handle_t *jbd2_journal_start(journal_t *, int nblocks); 1360 extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks, 1361 gfp_t gfp_mask, unsigned int type, 1362 unsigned int line_no); 1363 extern int jbd2_journal_restart(handle_t *, int nblocks); 1364 extern int jbd2__journal_restart(handle_t *, int nblocks, gfp_t gfp_mask); 1365 extern int jbd2_journal_start_reserved(handle_t *handle, 1366 unsigned int type, unsigned int line_no); 1367 extern void jbd2_journal_free_reserved(handle_t *handle); 1368 extern int jbd2_journal_extend (handle_t *, int nblocks); 1369 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *); 1370 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *); 1371 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *); 1372 void jbd2_journal_set_triggers(struct buffer_head *, 1373 struct jbd2_buffer_trigger_type *type); 1374 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *); 1375 extern int jbd2_journal_forget (handle_t *, struct buffer_head *); 1376 extern int jbd2_journal_invalidatepage(journal_t *, 1377 struct page *, unsigned int, unsigned int); 1378 extern int jbd2_journal_try_to_free_buffers(journal_t *, struct page *, gfp_t); 1379 extern int jbd2_journal_stop(handle_t *); 1380 extern int jbd2_journal_flush (journal_t *); 1381 extern void jbd2_journal_lock_updates (journal_t *); 1382 extern void jbd2_journal_unlock_updates (journal_t *); 1383 1384 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev, 1385 struct block_device *fs_dev, 1386 unsigned long long start, int len, int bsize); 1387 extern journal_t * jbd2_journal_init_inode (struct inode *); 1388 extern int jbd2_journal_update_format (journal_t *); 1389 extern int jbd2_journal_check_used_features 1390 (journal_t *, unsigned long, unsigned long, unsigned long); 1391 extern int jbd2_journal_check_available_features 1392 (journal_t *, unsigned long, unsigned long, unsigned long); 1393 extern int jbd2_journal_set_features 1394 (journal_t *, unsigned long, unsigned long, unsigned long); 1395 extern void jbd2_journal_clear_features 1396 (journal_t *, unsigned long, unsigned long, unsigned long); 1397 extern int jbd2_journal_load (journal_t *journal); 1398 extern int jbd2_journal_destroy (journal_t *); 1399 extern int jbd2_journal_recover (journal_t *journal); 1400 extern int jbd2_journal_wipe (journal_t *, int); 1401 extern int jbd2_journal_skip_recovery (journal_t *); 1402 extern void jbd2_journal_update_sb_errno(journal_t *); 1403 extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t, 1404 unsigned long, int); 1405 extern void __jbd2_journal_abort_hard (journal_t *); 1406 extern void jbd2_journal_abort (journal_t *, int); 1407 extern int jbd2_journal_errno (journal_t *); 1408 extern void jbd2_journal_ack_err (journal_t *); 1409 extern int jbd2_journal_clear_err (journal_t *); 1410 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *); 1411 extern int jbd2_journal_force_commit(journal_t *); 1412 extern int jbd2_journal_force_commit_nested(journal_t *); 1413 extern int jbd2_journal_inode_add_write(handle_t *handle, struct jbd2_inode *inode); 1414 extern int jbd2_journal_inode_add_wait(handle_t *handle, struct jbd2_inode *inode); 1415 extern int jbd2_journal_inode_ranged_write(handle_t *handle, 1416 struct jbd2_inode *inode, loff_t start_byte, 1417 loff_t length); 1418 extern int jbd2_journal_inode_ranged_wait(handle_t *handle, 1419 struct jbd2_inode *inode, loff_t start_byte, 1420 loff_t length); 1421 extern int jbd2_journal_begin_ordered_truncate(journal_t *journal, 1422 struct jbd2_inode *inode, loff_t new_size); 1423 extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode); 1424 extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode); 1425 1426 /* 1427 * journal_head management 1428 */ 1429 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh); 1430 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh); 1431 void jbd2_journal_put_journal_head(struct journal_head *jh); 1432 1433 /* 1434 * handle management 1435 */ 1436 extern struct kmem_cache *jbd2_handle_cache; 1437 1438 static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags) 1439 { 1440 return kmem_cache_zalloc(jbd2_handle_cache, gfp_flags); 1441 } 1442 1443 static inline void jbd2_free_handle(handle_t *handle) 1444 { 1445 kmem_cache_free(jbd2_handle_cache, handle); 1446 } 1447 1448 /* 1449 * jbd2_inode management (optional, for those file systems that want to use 1450 * dynamically allocated jbd2_inode structures) 1451 */ 1452 extern struct kmem_cache *jbd2_inode_cache; 1453 1454 static inline struct jbd2_inode *jbd2_alloc_inode(gfp_t gfp_flags) 1455 { 1456 return kmem_cache_alloc(jbd2_inode_cache, gfp_flags); 1457 } 1458 1459 static inline void jbd2_free_inode(struct jbd2_inode *jinode) 1460 { 1461 kmem_cache_free(jbd2_inode_cache, jinode); 1462 } 1463 1464 /* Primary revoke support */ 1465 #define JOURNAL_REVOKE_DEFAULT_HASH 256 1466 extern int jbd2_journal_init_revoke(journal_t *, int); 1467 extern void jbd2_journal_destroy_revoke_record_cache(void); 1468 extern void jbd2_journal_destroy_revoke_table_cache(void); 1469 extern int __init jbd2_journal_init_revoke_record_cache(void); 1470 extern int __init jbd2_journal_init_revoke_table_cache(void); 1471 1472 extern void jbd2_journal_destroy_revoke(journal_t *); 1473 extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *); 1474 extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *); 1475 extern void jbd2_journal_write_revoke_records(transaction_t *transaction, 1476 struct list_head *log_bufs); 1477 1478 /* Recovery revoke support */ 1479 extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t); 1480 extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t); 1481 extern void jbd2_journal_clear_revoke(journal_t *); 1482 extern void jbd2_journal_switch_revoke_table(journal_t *journal); 1483 extern void jbd2_clear_buffer_revoked_flags(journal_t *journal); 1484 1485 /* 1486 * The log thread user interface: 1487 * 1488 * Request space in the current transaction, and force transaction commit 1489 * transitions on demand. 1490 */ 1491 1492 int jbd2_log_start_commit(journal_t *journal, tid_t tid); 1493 int __jbd2_log_start_commit(journal_t *journal, tid_t tid); 1494 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid); 1495 int jbd2_log_wait_commit(journal_t *journal, tid_t tid); 1496 int jbd2_transaction_committed(journal_t *journal, tid_t tid); 1497 int jbd2_complete_transaction(journal_t *journal, tid_t tid); 1498 int jbd2_log_do_checkpoint(journal_t *journal); 1499 int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid); 1500 1501 void __jbd2_log_wait_for_space(journal_t *journal); 1502 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *); 1503 extern int jbd2_cleanup_journal_tail(journal_t *); 1504 1505 /* 1506 * is_journal_abort 1507 * 1508 * Simple test wrapper function to test the JBD2_ABORT state flag. This 1509 * bit, when set, indicates that we have had a fatal error somewhere, 1510 * either inside the journaling layer or indicated to us by the client 1511 * (eg. ext3), and that we and should not commit any further 1512 * transactions. 1513 */ 1514 1515 static inline int is_journal_aborted(journal_t *journal) 1516 { 1517 return journal->j_flags & JBD2_ABORT; 1518 } 1519 1520 static inline int is_handle_aborted(handle_t *handle) 1521 { 1522 if (handle->h_aborted || !handle->h_transaction) 1523 return 1; 1524 return is_journal_aborted(handle->h_transaction->t_journal); 1525 } 1526 1527 static inline void jbd2_journal_abort_handle(handle_t *handle) 1528 { 1529 handle->h_aborted = 1; 1530 } 1531 1532 #endif /* __KERNEL__ */ 1533 1534 /* Comparison functions for transaction IDs: perform comparisons using 1535 * modulo arithmetic so that they work over sequence number wraps. */ 1536 1537 static inline int tid_gt(tid_t x, tid_t y) 1538 { 1539 int difference = (x - y); 1540 return (difference > 0); 1541 } 1542 1543 static inline int tid_geq(tid_t x, tid_t y) 1544 { 1545 int difference = (x - y); 1546 return (difference >= 0); 1547 } 1548 1549 extern int jbd2_journal_blocks_per_page(struct inode *inode); 1550 extern size_t journal_tag_bytes(journal_t *journal); 1551 1552 static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j) 1553 { 1554 return jbd2_has_feature_csum2(j) || jbd2_has_feature_csum3(j); 1555 } 1556 1557 static inline int jbd2_journal_has_csum_v2or3(journal_t *journal) 1558 { 1559 WARN_ON_ONCE(jbd2_journal_has_csum_v2or3_feature(journal) && 1560 journal->j_chksum_driver == NULL); 1561 1562 return journal->j_chksum_driver != NULL; 1563 } 1564 1565 /* 1566 * We reserve t_outstanding_credits >> JBD2_CONTROL_BLOCKS_SHIFT for 1567 * transaction control blocks. 1568 */ 1569 #define JBD2_CONTROL_BLOCKS_SHIFT 5 1570 1571 /* 1572 * Return the minimum number of blocks which must be free in the journal 1573 * before a new transaction may be started. Must be called under j_state_lock. 1574 */ 1575 static inline int jbd2_space_needed(journal_t *journal) 1576 { 1577 int nblocks = journal->j_max_transaction_buffers; 1578 return nblocks + (nblocks >> JBD2_CONTROL_BLOCKS_SHIFT); 1579 } 1580 1581 /* 1582 * Return number of free blocks in the log. Must be called under j_state_lock. 1583 */ 1584 static inline unsigned long jbd2_log_space_left(journal_t *journal) 1585 { 1586 /* Allow for rounding errors */ 1587 unsigned long free = journal->j_free - 32; 1588 1589 if (journal->j_committing_transaction) { 1590 unsigned long committing = atomic_read(&journal-> 1591 j_committing_transaction->t_outstanding_credits); 1592 1593 /* Transaction + control blocks */ 1594 free -= committing + (committing >> JBD2_CONTROL_BLOCKS_SHIFT); 1595 } 1596 return free; 1597 } 1598 1599 /* 1600 * Definitions which augment the buffer_head layer 1601 */ 1602 1603 /* journaling buffer types */ 1604 #define BJ_None 0 /* Not journaled */ 1605 #define BJ_Metadata 1 /* Normal journaled metadata */ 1606 #define BJ_Forget 2 /* Buffer superseded by this transaction */ 1607 #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */ 1608 #define BJ_Reserved 4 /* Buffer is reserved for access by journal */ 1609 #define BJ_Types 5 1610 1611 extern int jbd_blocks_per_page(struct inode *inode); 1612 1613 /* JBD uses a CRC32 checksum */ 1614 #define JBD_MAX_CHECKSUM_SIZE 4 1615 1616 static inline u32 jbd2_chksum(journal_t *journal, u32 crc, 1617 const void *address, unsigned int length) 1618 { 1619 struct { 1620 struct shash_desc shash; 1621 char ctx[JBD_MAX_CHECKSUM_SIZE]; 1622 } desc; 1623 int err; 1624 1625 BUG_ON(crypto_shash_descsize(journal->j_chksum_driver) > 1626 JBD_MAX_CHECKSUM_SIZE); 1627 1628 desc.shash.tfm = journal->j_chksum_driver; 1629 *(u32 *)desc.ctx = crc; 1630 1631 err = crypto_shash_update(&desc.shash, address, length); 1632 BUG_ON(err); 1633 1634 return *(u32 *)desc.ctx; 1635 } 1636 1637 /* Return most recent uncommitted transaction */ 1638 static inline tid_t jbd2_get_latest_transaction(journal_t *journal) 1639 { 1640 tid_t tid; 1641 1642 read_lock(&journal->j_state_lock); 1643 tid = journal->j_commit_request; 1644 if (journal->j_running_transaction) 1645 tid = journal->j_running_transaction->t_tid; 1646 read_unlock(&journal->j_state_lock); 1647 return tid; 1648 } 1649 1650 #ifdef __KERNEL__ 1651 1652 #define buffer_trace_init(bh) do {} while (0) 1653 #define print_buffer_fields(bh) do {} while (0) 1654 #define print_buffer_trace(bh) do {} while (0) 1655 #define BUFFER_TRACE(bh, info) do {} while (0) 1656 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0) 1657 #define JBUFFER_TRACE(jh, info) do {} while (0) 1658 1659 #endif /* __KERNEL__ */ 1660 1661 #define EFSBADCRC EBADMSG /* Bad CRC detected */ 1662 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ 1663 1664 #endif /* _LINUX_JBD2_H */ 1665