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 #define JBD2_MIN_FC_BLOCKS 256 72 73 #ifdef __KERNEL__ 74 75 /** 76 * typedef handle_t - The handle_t type represents a single atomic update being performed by some process. 77 * 78 * All filesystem modifications made by the process go 79 * through this handle. Recursive operations (such as quota operations) 80 * are gathered into a single update. 81 * 82 * The buffer credits field is used to account for journaled buffers 83 * being modified by the running process. To ensure that there is 84 * enough log space for all outstanding operations, we need to limit the 85 * number of outstanding buffers possible at any time. When the 86 * operation completes, any buffer credits not used are credited back to 87 * the transaction, so that at all times we know how many buffers the 88 * outstanding updates on a transaction might possibly touch. 89 * 90 * This is an opaque datatype. 91 **/ 92 typedef struct jbd2_journal_handle handle_t; /* Atomic operation type */ 93 94 95 /** 96 * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem. 97 * 98 * journal_t is linked to from the fs superblock structure. 99 * 100 * We use the journal_t to keep track of all outstanding transaction 101 * activity on the filesystem, and to manage the state of the log 102 * writing process. 103 * 104 * This is an opaque datatype. 105 **/ 106 typedef struct journal_s journal_t; /* Journal control structure */ 107 #endif 108 109 /* 110 * Internal structures used by the logging mechanism: 111 */ 112 113 #define JBD2_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */ 114 115 /* 116 * On-disk structures 117 */ 118 119 /* 120 * Descriptor block types: 121 */ 122 123 #define JBD2_DESCRIPTOR_BLOCK 1 124 #define JBD2_COMMIT_BLOCK 2 125 #define JBD2_SUPERBLOCK_V1 3 126 #define JBD2_SUPERBLOCK_V2 4 127 #define JBD2_REVOKE_BLOCK 5 128 129 /* 130 * Standard header for all descriptor blocks: 131 */ 132 typedef struct journal_header_s 133 { 134 __be32 h_magic; 135 __be32 h_blocktype; 136 __be32 h_sequence; 137 } journal_header_t; 138 139 /* 140 * Checksum types. 141 */ 142 #define JBD2_CRC32_CHKSUM 1 143 #define JBD2_MD5_CHKSUM 2 144 #define JBD2_SHA1_CHKSUM 3 145 #define JBD2_CRC32C_CHKSUM 4 146 147 #define JBD2_CRC32_CHKSUM_SIZE 4 148 149 #define JBD2_CHECKSUM_BYTES (32 / sizeof(u32)) 150 /* 151 * Commit block header for storing transactional checksums: 152 * 153 * NOTE: If FEATURE_COMPAT_CHECKSUM (checksum v1) is set, the h_chksum* 154 * fields are used to store a checksum of the descriptor and data blocks. 155 * 156 * If FEATURE_INCOMPAT_CSUM_V2 (checksum v2) is set, then the h_chksum 157 * field is used to store crc32c(uuid+commit_block). Each journal metadata 158 * block gets its own checksum, and data block checksums are stored in 159 * journal_block_tag (in the descriptor). The other h_chksum* fields are 160 * not used. 161 * 162 * If FEATURE_INCOMPAT_CSUM_V3 is set, the descriptor block uses 163 * journal_block_tag3_t to store a full 32-bit checksum. Everything else 164 * is the same as v2. 165 * 166 * Checksum v1, v2, and v3 are mutually exclusive features. 167 */ 168 struct commit_header { 169 __be32 h_magic; 170 __be32 h_blocktype; 171 __be32 h_sequence; 172 unsigned char h_chksum_type; 173 unsigned char h_chksum_size; 174 unsigned char h_padding[2]; 175 __be32 h_chksum[JBD2_CHECKSUM_BYTES]; 176 __be64 h_commit_sec; 177 __be32 h_commit_nsec; 178 }; 179 180 /* 181 * The block tag: used to describe a single buffer in the journal. 182 * t_blocknr_high is only used if INCOMPAT_64BIT is set, so this 183 * raw struct shouldn't be used for pointer math or sizeof() - use 184 * journal_tag_bytes(journal) instead to compute this. 185 */ 186 typedef struct journal_block_tag3_s 187 { 188 __be32 t_blocknr; /* The on-disk block number */ 189 __be32 t_flags; /* See below */ 190 __be32 t_blocknr_high; /* most-significant high 32bits. */ 191 __be32 t_checksum; /* crc32c(uuid+seq+block) */ 192 } journal_block_tag3_t; 193 194 typedef struct journal_block_tag_s 195 { 196 __be32 t_blocknr; /* The on-disk block number */ 197 __be16 t_checksum; /* truncated crc32c(uuid+seq+block) */ 198 __be16 t_flags; /* See below */ 199 __be32 t_blocknr_high; /* most-significant high 32bits. */ 200 } journal_block_tag_t; 201 202 /* Tail of descriptor or revoke block, for checksumming */ 203 struct jbd2_journal_block_tail { 204 __be32 t_checksum; /* crc32c(uuid+descr_block) */ 205 }; 206 207 /* 208 * The revoke descriptor: used on disk to describe a series of blocks to 209 * be revoked from the log 210 */ 211 typedef struct jbd2_journal_revoke_header_s 212 { 213 journal_header_t r_header; 214 __be32 r_count; /* Count of bytes used in the block */ 215 } jbd2_journal_revoke_header_t; 216 217 /* Definitions for the journal tag flags word: */ 218 #define JBD2_FLAG_ESCAPE 1 /* on-disk block is escaped */ 219 #define JBD2_FLAG_SAME_UUID 2 /* block has same uuid as previous */ 220 #define JBD2_FLAG_DELETED 4 /* block deleted by this transaction */ 221 #define JBD2_FLAG_LAST_TAG 8 /* last tag in this descriptor block */ 222 223 224 /* 225 * The journal superblock. All fields are in big-endian byte order. 226 */ 227 typedef struct journal_superblock_s 228 { 229 /* 0x0000 */ 230 journal_header_t s_header; 231 232 /* 0x000C */ 233 /* Static information describing the journal */ 234 __be32 s_blocksize; /* journal device blocksize */ 235 __be32 s_maxlen; /* total blocks in journal file */ 236 __be32 s_first; /* first block of log information */ 237 238 /* 0x0018 */ 239 /* Dynamic information describing the current state of the log */ 240 __be32 s_sequence; /* first commit ID expected in log */ 241 __be32 s_start; /* blocknr of start of log */ 242 243 /* 0x0020 */ 244 /* Error value, as set by jbd2_journal_abort(). */ 245 __be32 s_errno; 246 247 /* 0x0024 */ 248 /* Remaining fields are only valid in a version-2 superblock */ 249 __be32 s_feature_compat; /* compatible feature set */ 250 __be32 s_feature_incompat; /* incompatible feature set */ 251 __be32 s_feature_ro_compat; /* readonly-compatible feature set */ 252 /* 0x0030 */ 253 __u8 s_uuid[16]; /* 128-bit uuid for journal */ 254 255 /* 0x0040 */ 256 __be32 s_nr_users; /* Nr of filesystems sharing log */ 257 258 __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/ 259 260 /* 0x0048 */ 261 __be32 s_max_transaction; /* Limit of journal blocks per trans.*/ 262 __be32 s_max_trans_data; /* Limit of data blocks per trans. */ 263 264 /* 0x0050 */ 265 __u8 s_checksum_type; /* checksum type */ 266 __u8 s_padding2[3]; 267 /* 0x0054 */ 268 __be32 s_num_fc_blks; /* Number of fast commit blocks */ 269 /* 0x0058 */ 270 __u32 s_padding[41]; 271 __be32 s_checksum; /* crc32c(superblock) */ 272 273 /* 0x0100 */ 274 __u8 s_users[16*48]; /* ids of all fs'es sharing the log */ 275 /* 0x0400 */ 276 } journal_superblock_t; 277 278 /* Use the jbd2_{has,set,clear}_feature_* helpers; these will be removed */ 279 #define JBD2_HAS_COMPAT_FEATURE(j,mask) \ 280 ((j)->j_format_version >= 2 && \ 281 ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask)))) 282 #define JBD2_HAS_RO_COMPAT_FEATURE(j,mask) \ 283 ((j)->j_format_version >= 2 && \ 284 ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask)))) 285 #define JBD2_HAS_INCOMPAT_FEATURE(j,mask) \ 286 ((j)->j_format_version >= 2 && \ 287 ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask)))) 288 289 #define JBD2_FEATURE_COMPAT_CHECKSUM 0x00000001 290 291 #define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001 292 #define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002 293 #define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT 0x00000004 294 #define JBD2_FEATURE_INCOMPAT_CSUM_V2 0x00000008 295 #define JBD2_FEATURE_INCOMPAT_CSUM_V3 0x00000010 296 #define JBD2_FEATURE_INCOMPAT_FAST_COMMIT 0x00000020 297 298 /* See "journal feature predicate functions" below */ 299 300 /* Features known to this kernel version: */ 301 #define JBD2_KNOWN_COMPAT_FEATURES JBD2_FEATURE_COMPAT_CHECKSUM 302 #define JBD2_KNOWN_ROCOMPAT_FEATURES 0 303 #define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \ 304 JBD2_FEATURE_INCOMPAT_64BIT | \ 305 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | \ 306 JBD2_FEATURE_INCOMPAT_CSUM_V2 | \ 307 JBD2_FEATURE_INCOMPAT_CSUM_V3 | \ 308 JBD2_FEATURE_INCOMPAT_FAST_COMMIT) 309 310 #ifdef __KERNEL__ 311 312 #include <linux/fs.h> 313 #include <linux/sched.h> 314 315 enum jbd_state_bits { 316 BH_JBD /* Has an attached ext3 journal_head */ 317 = BH_PrivateStart, 318 BH_JWrite, /* Being written to log (@@@ DEBUGGING) */ 319 BH_Freed, /* Has been freed (truncated) */ 320 BH_Revoked, /* Has been revoked from the log */ 321 BH_RevokeValid, /* Revoked flag is valid */ 322 BH_JBDDirty, /* Is dirty but journaled */ 323 BH_JournalHead, /* Pins bh->b_private and jh->b_bh */ 324 BH_Shadow, /* IO on shadow buffer is running */ 325 BH_Verified, /* Metadata block has been verified ok */ 326 BH_JBDPrivateStart, /* First bit available for private use by FS */ 327 }; 328 329 BUFFER_FNS(JBD, jbd) 330 BUFFER_FNS(JWrite, jwrite) 331 BUFFER_FNS(JBDDirty, jbddirty) 332 TAS_BUFFER_FNS(JBDDirty, jbddirty) 333 BUFFER_FNS(Revoked, revoked) 334 TAS_BUFFER_FNS(Revoked, revoked) 335 BUFFER_FNS(RevokeValid, revokevalid) 336 TAS_BUFFER_FNS(RevokeValid, revokevalid) 337 BUFFER_FNS(Freed, freed) 338 BUFFER_FNS(Shadow, shadow) 339 BUFFER_FNS(Verified, verified) 340 341 static inline struct buffer_head *jh2bh(struct journal_head *jh) 342 { 343 return jh->b_bh; 344 } 345 346 static inline struct journal_head *bh2jh(struct buffer_head *bh) 347 { 348 return bh->b_private; 349 } 350 351 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh) 352 { 353 bit_spin_lock(BH_JournalHead, &bh->b_state); 354 } 355 356 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh) 357 { 358 bit_spin_unlock(BH_JournalHead, &bh->b_state); 359 } 360 361 #define J_ASSERT(assert) BUG_ON(!(assert)) 362 363 #define J_ASSERT_BH(bh, expr) J_ASSERT(expr) 364 #define J_ASSERT_JH(jh, expr) J_ASSERT(expr) 365 366 #if defined(JBD2_PARANOID_IOFAIL) 367 #define J_EXPECT(expr, why...) J_ASSERT(expr) 368 #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr) 369 #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr) 370 #else 371 #define __journal_expect(expr, why...) \ 372 ({ \ 373 int val = (expr); \ 374 if (!val) { \ 375 printk(KERN_ERR \ 376 "JBD2 unexpected failure: %s: %s;\n", \ 377 __func__, #expr); \ 378 printk(KERN_ERR why "\n"); \ 379 } \ 380 val; \ 381 }) 382 #define J_EXPECT(expr, why...) __journal_expect(expr, ## why) 383 #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why) 384 #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why) 385 #endif 386 387 /* Flags in jbd_inode->i_flags */ 388 #define __JI_COMMIT_RUNNING 0 389 #define __JI_WRITE_DATA 1 390 #define __JI_WAIT_DATA 2 391 392 /* 393 * Commit of the inode data in progress. We use this flag to protect us from 394 * concurrent deletion of inode. We cannot use reference to inode for this 395 * since we cannot afford doing last iput() on behalf of kjournald 396 */ 397 #define JI_COMMIT_RUNNING (1 << __JI_COMMIT_RUNNING) 398 /* Write allocated dirty buffers in this inode before commit */ 399 #define JI_WRITE_DATA (1 << __JI_WRITE_DATA) 400 /* Wait for outstanding data writes for this inode before commit */ 401 #define JI_WAIT_DATA (1 << __JI_WAIT_DATA) 402 403 /** 404 * struct jbd_inode - The jbd_inode type is the structure linking inodes in 405 * ordered mode present in a transaction so that we can sync them during commit. 406 */ 407 struct jbd2_inode { 408 /** 409 * @i_transaction: 410 * 411 * Which transaction does this inode belong to? Either the running 412 * transaction or the committing one. [j_list_lock] 413 */ 414 transaction_t *i_transaction; 415 416 /** 417 * @i_next_transaction: 418 * 419 * Pointer to the running transaction modifying inode's data in case 420 * there is already a committing transaction touching it. [j_list_lock] 421 */ 422 transaction_t *i_next_transaction; 423 424 /** 425 * @i_list: List of inodes in the i_transaction [j_list_lock] 426 */ 427 struct list_head i_list; 428 429 /** 430 * @i_vfs_inode: 431 * 432 * VFS inode this inode belongs to [constant for lifetime of structure] 433 */ 434 struct inode *i_vfs_inode; 435 436 /** 437 * @i_flags: Flags of inode [j_list_lock] 438 */ 439 unsigned long i_flags; 440 441 /** 442 * @i_dirty_start: 443 * 444 * Offset in bytes where the dirty range for this inode starts. 445 * [j_list_lock] 446 */ 447 loff_t i_dirty_start; 448 449 /** 450 * @i_dirty_end: 451 * 452 * Inclusive offset in bytes where the dirty range for this inode 453 * ends. [j_list_lock] 454 */ 455 loff_t i_dirty_end; 456 }; 457 458 struct jbd2_revoke_table_s; 459 460 /** 461 * struct jbd2_journal_handle - The jbd2_journal_handle type is the concrete 462 * type associated with handle_t. 463 * @h_transaction: Which compound transaction is this update a part of? 464 * @h_journal: Which journal handle belongs to - used iff h_reserved set. 465 * @h_rsv_handle: Handle reserved for finishing the logical operation. 466 * @h_total_credits: Number of remaining buffers we are allowed to add to 467 * journal. These are dirty buffers and revoke descriptor blocks. 468 * @h_revoke_credits: Number of remaining revoke records available for handle 469 * @h_ref: Reference count on this handle. 470 * @h_err: Field for caller's use to track errors through large fs operations. 471 * @h_sync: Flag for sync-on-close. 472 * @h_jdata: Flag to force data journaling. 473 * @h_reserved: Flag for handle for reserved credits. 474 * @h_aborted: Flag indicating fatal error on handle. 475 * @h_type: For handle statistics. 476 * @h_line_no: For handle statistics. 477 * @h_start_jiffies: Handle Start time. 478 * @h_requested_credits: Holds @h_total_credits after handle is started. 479 * @h_revoke_credits_requested: Holds @h_revoke_credits after handle is started. 480 * @saved_alloc_context: Saved context while transaction is open. 481 **/ 482 483 /* Docbook can't yet cope with the bit fields, but will leave the documentation 484 * in so it can be fixed later. 485 */ 486 487 struct jbd2_journal_handle 488 { 489 union { 490 transaction_t *h_transaction; 491 /* Which journal handle belongs to - used iff h_reserved set */ 492 journal_t *h_journal; 493 }; 494 495 handle_t *h_rsv_handle; 496 int h_total_credits; 497 int h_revoke_credits; 498 int h_revoke_credits_requested; 499 int h_ref; 500 int h_err; 501 502 /* Flags [no locking] */ 503 unsigned int h_sync: 1; 504 unsigned int h_jdata: 1; 505 unsigned int h_reserved: 1; 506 unsigned int h_aborted: 1; 507 unsigned int h_type: 8; 508 unsigned int h_line_no: 16; 509 510 unsigned long h_start_jiffies; 511 unsigned int h_requested_credits; 512 513 unsigned int saved_alloc_context; 514 }; 515 516 517 /* 518 * Some stats for checkpoint phase 519 */ 520 struct transaction_chp_stats_s { 521 unsigned long cs_chp_time; 522 __u32 cs_forced_to_close; 523 __u32 cs_written; 524 __u32 cs_dropped; 525 }; 526 527 /* The transaction_t type is the guts of the journaling mechanism. It 528 * tracks a compound transaction through its various states: 529 * 530 * RUNNING: accepting new updates 531 * LOCKED: Updates still running but we don't accept new ones 532 * RUNDOWN: Updates are tidying up but have finished requesting 533 * new buffers to modify (state not used for now) 534 * FLUSH: All updates complete, but we are still writing to disk 535 * COMMIT: All data on disk, writing commit record 536 * FINISHED: We still have to keep the transaction for checkpointing. 537 * 538 * The transaction keeps track of all of the buffers modified by a 539 * running transaction, and all of the buffers committed but not yet 540 * flushed to home for finished transactions. 541 */ 542 543 /* 544 * Lock ranking: 545 * 546 * j_list_lock 547 * ->jbd_lock_bh_journal_head() (This is "innermost") 548 * 549 * j_state_lock 550 * ->b_state_lock 551 * 552 * b_state_lock 553 * ->j_list_lock 554 * 555 * j_state_lock 556 * ->t_handle_lock 557 * 558 * j_state_lock 559 * ->j_list_lock (journal_unmap_buffer) 560 * 561 */ 562 563 struct transaction_s 564 { 565 /* Pointer to the journal for this transaction. [no locking] */ 566 journal_t *t_journal; 567 568 /* Sequence number for this transaction [no locking] */ 569 tid_t t_tid; 570 571 /* 572 * Transaction's current state 573 * [no locking - only kjournald2 alters this] 574 * [j_list_lock] guards transition of a transaction into T_FINISHED 575 * state and subsequent call of __jbd2_journal_drop_transaction() 576 * FIXME: needs barriers 577 * KLUDGE: [use j_state_lock] 578 */ 579 enum { 580 T_RUNNING, 581 T_LOCKED, 582 T_SWITCH, 583 T_FLUSH, 584 T_COMMIT, 585 T_COMMIT_DFLUSH, 586 T_COMMIT_JFLUSH, 587 T_COMMIT_CALLBACK, 588 T_FINISHED 589 } t_state; 590 591 /* 592 * Where in the log does this transaction's commit start? [no locking] 593 */ 594 unsigned long t_log_start; 595 596 /* Number of buffers on the t_buffers list [j_list_lock] */ 597 int t_nr_buffers; 598 599 /* 600 * Doubly-linked circular list of all buffers reserved but not yet 601 * modified by this transaction [j_list_lock] 602 */ 603 struct journal_head *t_reserved_list; 604 605 /* 606 * Doubly-linked circular list of all metadata buffers owned by this 607 * transaction [j_list_lock] 608 */ 609 struct journal_head *t_buffers; 610 611 /* 612 * Doubly-linked circular list of all forget buffers (superseded 613 * buffers which we can un-checkpoint once this transaction commits) 614 * [j_list_lock] 615 */ 616 struct journal_head *t_forget; 617 618 /* 619 * Doubly-linked circular list of all buffers still to be flushed before 620 * this transaction can be checkpointed. [j_list_lock] 621 */ 622 struct journal_head *t_checkpoint_list; 623 624 /* 625 * Doubly-linked circular list of all buffers submitted for IO while 626 * checkpointing. [j_list_lock] 627 */ 628 struct journal_head *t_checkpoint_io_list; 629 630 /* 631 * Doubly-linked circular list of metadata buffers being shadowed by log 632 * IO. The IO buffers on the iobuf list and the shadow buffers on this 633 * list match each other one for one at all times. [j_list_lock] 634 */ 635 struct journal_head *t_shadow_list; 636 637 /* 638 * List of inodes associated with the transaction; e.g., ext4 uses 639 * this to track inodes in data=ordered and data=journal mode that 640 * need special handling on transaction commit; also used by ocfs2. 641 * [j_list_lock] 642 */ 643 struct list_head t_inode_list; 644 645 /* 646 * Protects info related to handles 647 */ 648 spinlock_t t_handle_lock; 649 650 /* 651 * Longest time some handle had to wait for running transaction 652 */ 653 unsigned long t_max_wait; 654 655 /* 656 * When transaction started 657 */ 658 unsigned long t_start; 659 660 /* 661 * When commit was requested 662 */ 663 unsigned long t_requested; 664 665 /* 666 * Checkpointing stats [j_checkpoint_sem] 667 */ 668 struct transaction_chp_stats_s t_chp_stats; 669 670 /* 671 * Number of outstanding updates running on this transaction 672 * [none] 673 */ 674 atomic_t t_updates; 675 676 /* 677 * Number of blocks reserved for this transaction in the journal. 678 * This is including all credits reserved when starting transaction 679 * handles as well as all journal descriptor blocks needed for this 680 * transaction. [none] 681 */ 682 atomic_t t_outstanding_credits; 683 684 /* 685 * Number of revoke records for this transaction added by already 686 * stopped handles. [none] 687 */ 688 atomic_t t_outstanding_revokes; 689 690 /* 691 * How many handles used this transaction? [none] 692 */ 693 atomic_t t_handle_count; 694 695 /* 696 * Forward and backward links for the circular list of all transactions 697 * awaiting checkpoint. [j_list_lock] 698 */ 699 transaction_t *t_cpnext, *t_cpprev; 700 701 /* 702 * When will the transaction expire (become due for commit), in jiffies? 703 * [no locking] 704 */ 705 unsigned long t_expires; 706 707 /* 708 * When this transaction started, in nanoseconds [no locking] 709 */ 710 ktime_t t_start_time; 711 712 /* 713 * This transaction is being forced and some process is 714 * waiting for it to finish. 715 */ 716 unsigned int t_synchronous_commit:1; 717 718 /* Disk flush needs to be sent to fs partition [no locking] */ 719 int t_need_data_flush; 720 721 /* 722 * For use by the filesystem to store fs-specific data 723 * structures associated with the transaction 724 */ 725 struct list_head t_private_list; 726 }; 727 728 struct transaction_run_stats_s { 729 unsigned long rs_wait; 730 unsigned long rs_request_delay; 731 unsigned long rs_running; 732 unsigned long rs_locked; 733 unsigned long rs_flushing; 734 unsigned long rs_logging; 735 736 __u32 rs_handle_count; 737 __u32 rs_blocks; 738 __u32 rs_blocks_logged; 739 }; 740 741 struct transaction_stats_s { 742 unsigned long ts_tid; 743 unsigned long ts_requested; 744 struct transaction_run_stats_s run; 745 }; 746 747 static inline unsigned long 748 jbd2_time_diff(unsigned long start, unsigned long end) 749 { 750 if (end >= start) 751 return end - start; 752 753 return end + (MAX_JIFFY_OFFSET - start); 754 } 755 756 #define JBD2_NR_BATCH 64 757 758 enum passtype {PASS_SCAN, PASS_REVOKE, PASS_REPLAY}; 759 760 #define JBD2_FC_REPLAY_STOP 0 761 #define JBD2_FC_REPLAY_CONTINUE 1 762 763 /** 764 * struct journal_s - The journal_s type is the concrete type associated with 765 * journal_t. 766 */ 767 struct journal_s 768 { 769 /** 770 * @j_flags: General journaling state flags [j_state_lock] 771 */ 772 unsigned long j_flags; 773 774 /** 775 * @j_errno: 776 * 777 * Is there an outstanding uncleared error on the journal (from a prior 778 * abort)? [j_state_lock] 779 */ 780 int j_errno; 781 782 /** 783 * @j_abort_mutex: Lock the whole aborting procedure. 784 */ 785 struct mutex j_abort_mutex; 786 787 /** 788 * @j_sb_buffer: The first part of the superblock buffer. 789 */ 790 struct buffer_head *j_sb_buffer; 791 792 /** 793 * @j_superblock: The second part of the superblock buffer. 794 */ 795 journal_superblock_t *j_superblock; 796 797 /** 798 * @j_format_version: Version of the superblock format. 799 */ 800 int j_format_version; 801 802 /** 803 * @j_state_lock: Protect the various scalars in the journal. 804 */ 805 rwlock_t j_state_lock; 806 807 /** 808 * @j_barrier_count: 809 * 810 * Number of processes waiting to create a barrier lock [j_state_lock] 811 */ 812 int j_barrier_count; 813 814 /** 815 * @j_barrier: The barrier lock itself. 816 */ 817 struct mutex j_barrier; 818 819 /** 820 * @j_running_transaction: 821 * 822 * Transactions: The current running transaction... 823 * [j_state_lock] [caller holding open handle] 824 */ 825 transaction_t *j_running_transaction; 826 827 /** 828 * @j_committing_transaction: 829 * 830 * the transaction we are pushing to disk 831 * [j_state_lock] [caller holding open handle] 832 */ 833 transaction_t *j_committing_transaction; 834 835 /** 836 * @j_checkpoint_transactions: 837 * 838 * ... and a linked circular list of all transactions waiting for 839 * checkpointing. [j_list_lock] 840 */ 841 transaction_t *j_checkpoint_transactions; 842 843 /** 844 * @j_wait_transaction_locked: 845 * 846 * Wait queue for waiting for a locked transaction to start committing, 847 * or for a barrier lock to be released. 848 */ 849 wait_queue_head_t j_wait_transaction_locked; 850 851 /** 852 * @j_wait_done_commit: Wait queue for waiting for commit to complete. 853 */ 854 wait_queue_head_t j_wait_done_commit; 855 856 /** 857 * @j_wait_commit: Wait queue to trigger commit. 858 */ 859 wait_queue_head_t j_wait_commit; 860 861 /** 862 * @j_wait_updates: Wait queue to wait for updates to complete. 863 */ 864 wait_queue_head_t j_wait_updates; 865 866 /** 867 * @j_wait_reserved: 868 * 869 * Wait queue to wait for reserved buffer credits to drop. 870 */ 871 wait_queue_head_t j_wait_reserved; 872 873 /** 874 * @j_fc_wait: 875 * 876 * Wait queue to wait for completion of async fast commits. 877 */ 878 wait_queue_head_t j_fc_wait; 879 880 /** 881 * @j_checkpoint_mutex: 882 * 883 * Semaphore for locking against concurrent checkpoints. 884 */ 885 struct mutex j_checkpoint_mutex; 886 887 /** 888 * @j_chkpt_bhs: 889 * 890 * List of buffer heads used by the checkpoint routine. This 891 * was moved from jbd2_log_do_checkpoint() to reduce stack 892 * usage. Access to this array is controlled by the 893 * @j_checkpoint_mutex. [j_checkpoint_mutex] 894 */ 895 struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH]; 896 897 /** 898 * @j_head: 899 * 900 * Journal head: identifies the first unused block in the journal. 901 * [j_state_lock] 902 */ 903 unsigned long j_head; 904 905 /** 906 * @j_tail: 907 * 908 * Journal tail: identifies the oldest still-used block in the journal. 909 * [j_state_lock] 910 */ 911 unsigned long j_tail; 912 913 /** 914 * @j_free: 915 * 916 * Journal free: how many free blocks are there in the journal? 917 * [j_state_lock] 918 */ 919 unsigned long j_free; 920 921 /** 922 * @j_first: 923 * 924 * The block number of the first usable block in the journal 925 * [j_state_lock]. 926 */ 927 unsigned long j_first; 928 929 /** 930 * @j_last: 931 * 932 * The block number one beyond the last usable block in the journal 933 * [j_state_lock]. 934 */ 935 unsigned long j_last; 936 937 /** 938 * @j_fc_first: 939 * 940 * The block number of the first fast commit block in the journal 941 * [j_state_lock]. 942 */ 943 unsigned long j_fc_first; 944 945 /** 946 * @j_fc_off: 947 * 948 * Number of fast commit blocks currently allocated. Accessed only 949 * during fast commit. Currently only process can do fast commit, so 950 * this field is not protected by any lock. 951 */ 952 unsigned long j_fc_off; 953 954 /** 955 * @j_fc_last: 956 * 957 * The block number one beyond the last fast commit block in the journal 958 * [j_state_lock]. 959 */ 960 unsigned long j_fc_last; 961 962 /** 963 * @j_dev: Device where we store the journal. 964 */ 965 struct block_device *j_dev; 966 967 /** 968 * @j_blocksize: Block size for the location where we store the journal. 969 */ 970 int j_blocksize; 971 972 /** 973 * @j_blk_offset: 974 * 975 * Starting block offset into the device where we store the journal. 976 */ 977 unsigned long long j_blk_offset; 978 979 /** 980 * @j_devname: Journal device name. 981 */ 982 char j_devname[BDEVNAME_SIZE+24]; 983 984 /** 985 * @j_fs_dev: 986 * 987 * Device which holds the client fs. For internal journal this will be 988 * equal to j_dev. 989 */ 990 struct block_device *j_fs_dev; 991 992 /** 993 * @j_total_len: Total maximum capacity of the journal region on disk. 994 */ 995 unsigned int j_total_len; 996 997 /** 998 * @j_reserved_credits: 999 * 1000 * Number of buffers reserved from the running transaction. 1001 */ 1002 atomic_t j_reserved_credits; 1003 1004 /** 1005 * @j_list_lock: Protects the buffer lists and internal buffer state. 1006 */ 1007 spinlock_t j_list_lock; 1008 1009 /** 1010 * @j_inode: 1011 * 1012 * Optional inode where we store the journal. If present, all 1013 * journal block numbers are mapped into this inode via bmap(). 1014 */ 1015 struct inode *j_inode; 1016 1017 /** 1018 * @j_tail_sequence: 1019 * 1020 * Sequence number of the oldest transaction in the log [j_state_lock] 1021 */ 1022 tid_t j_tail_sequence; 1023 1024 /** 1025 * @j_transaction_sequence: 1026 * 1027 * Sequence number of the next transaction to grant [j_state_lock] 1028 */ 1029 tid_t j_transaction_sequence; 1030 1031 /** 1032 * @j_commit_sequence: 1033 * 1034 * Sequence number of the most recently committed transaction 1035 * [j_state_lock]. 1036 */ 1037 tid_t j_commit_sequence; 1038 1039 /** 1040 * @j_commit_request: 1041 * 1042 * Sequence number of the most recent transaction wanting commit 1043 * [j_state_lock] 1044 */ 1045 tid_t j_commit_request; 1046 1047 /** 1048 * @j_uuid: 1049 * 1050 * Journal uuid: identifies the object (filesystem, LVM volume etc) 1051 * backed by this journal. This will eventually be replaced by an array 1052 * of uuids, allowing us to index multiple devices within a single 1053 * journal and to perform atomic updates across them. 1054 */ 1055 __u8 j_uuid[16]; 1056 1057 /** 1058 * @j_task: Pointer to the current commit thread for this journal. 1059 */ 1060 struct task_struct *j_task; 1061 1062 /** 1063 * @j_max_transaction_buffers: 1064 * 1065 * Maximum number of metadata buffers to allow in a single compound 1066 * commit transaction. 1067 */ 1068 int j_max_transaction_buffers; 1069 1070 /** 1071 * @j_revoke_records_per_block: 1072 * 1073 * Number of revoke records that fit in one descriptor block. 1074 */ 1075 int j_revoke_records_per_block; 1076 1077 /** 1078 * @j_commit_interval: 1079 * 1080 * What is the maximum transaction lifetime before we begin a commit? 1081 */ 1082 unsigned long j_commit_interval; 1083 1084 /** 1085 * @j_commit_timer: The timer used to wakeup the commit thread. 1086 */ 1087 struct timer_list j_commit_timer; 1088 1089 /** 1090 * @j_revoke_lock: Protect the revoke table. 1091 */ 1092 spinlock_t j_revoke_lock; 1093 1094 /** 1095 * @j_revoke: 1096 * 1097 * The revoke table - maintains the list of revoked blocks in the 1098 * current transaction. 1099 */ 1100 struct jbd2_revoke_table_s *j_revoke; 1101 1102 /** 1103 * @j_revoke_table: Alternate revoke tables for j_revoke. 1104 */ 1105 struct jbd2_revoke_table_s *j_revoke_table[2]; 1106 1107 /** 1108 * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction. 1109 */ 1110 struct buffer_head **j_wbuf; 1111 1112 /** 1113 * @j_fc_wbuf: Array of fast commit bhs for fast commit. Accessed only 1114 * during a fast commit. Currently only process can do fast commit, so 1115 * this field is not protected by any lock. 1116 */ 1117 struct buffer_head **j_fc_wbuf; 1118 1119 /** 1120 * @j_wbufsize: 1121 * 1122 * Size of @j_wbuf array. 1123 */ 1124 int j_wbufsize; 1125 1126 /** 1127 * @j_fc_wbufsize: 1128 * 1129 * Size of @j_fc_wbuf array. 1130 */ 1131 int j_fc_wbufsize; 1132 1133 /** 1134 * @j_last_sync_writer: 1135 * 1136 * The pid of the last person to run a synchronous operation 1137 * through the journal. 1138 */ 1139 pid_t j_last_sync_writer; 1140 1141 /** 1142 * @j_average_commit_time: 1143 * 1144 * The average amount of time in nanoseconds it takes to commit a 1145 * transaction to disk. [j_state_lock] 1146 */ 1147 u64 j_average_commit_time; 1148 1149 /** 1150 * @j_min_batch_time: 1151 * 1152 * Minimum time that we should wait for additional filesystem operations 1153 * to get batched into a synchronous handle in microseconds. 1154 */ 1155 u32 j_min_batch_time; 1156 1157 /** 1158 * @j_max_batch_time: 1159 * 1160 * Maximum time that we should wait for additional filesystem operations 1161 * to get batched into a synchronous handle in microseconds. 1162 */ 1163 u32 j_max_batch_time; 1164 1165 /** 1166 * @j_commit_callback: 1167 * 1168 * This function is called when a transaction is closed. 1169 */ 1170 void (*j_commit_callback)(journal_t *, 1171 transaction_t *); 1172 1173 /** 1174 * @j_submit_inode_data_buffers: 1175 * 1176 * This function is called for all inodes associated with the 1177 * committing transaction marked with JI_WRITE_DATA flag 1178 * before we start to write out the transaction to the journal. 1179 */ 1180 int (*j_submit_inode_data_buffers) 1181 (struct jbd2_inode *); 1182 1183 /** 1184 * @j_finish_inode_data_buffers: 1185 * 1186 * This function is called for all inodes associated with the 1187 * committing transaction marked with JI_WAIT_DATA flag 1188 * after we have written the transaction to the journal 1189 * but before we write out the commit block. 1190 */ 1191 int (*j_finish_inode_data_buffers) 1192 (struct jbd2_inode *); 1193 1194 /* 1195 * Journal statistics 1196 */ 1197 1198 /** 1199 * @j_history_lock: Protect the transactions statistics history. 1200 */ 1201 spinlock_t j_history_lock; 1202 1203 /** 1204 * @j_proc_entry: procfs entry for the jbd statistics directory. 1205 */ 1206 struct proc_dir_entry *j_proc_entry; 1207 1208 /** 1209 * @j_stats: Overall statistics. 1210 */ 1211 struct transaction_stats_s j_stats; 1212 1213 /** 1214 * @j_failed_commit: Failed journal commit ID. 1215 */ 1216 unsigned int j_failed_commit; 1217 1218 /** 1219 * @j_private: 1220 * 1221 * An opaque pointer to fs-private information. ext3 puts its 1222 * superblock pointer here. 1223 */ 1224 void *j_private; 1225 1226 /** 1227 * @j_chksum_driver: 1228 * 1229 * Reference to checksum algorithm driver via cryptoapi. 1230 */ 1231 struct crypto_shash *j_chksum_driver; 1232 1233 /** 1234 * @j_csum_seed: 1235 * 1236 * Precomputed journal UUID checksum for seeding other checksums. 1237 */ 1238 __u32 j_csum_seed; 1239 1240 #ifdef CONFIG_DEBUG_LOCK_ALLOC 1241 /** 1242 * @j_trans_commit_map: 1243 * 1244 * Lockdep entity to track transaction commit dependencies. Handles 1245 * hold this "lock" for read, when we wait for commit, we acquire the 1246 * "lock" for writing. This matches the properties of jbd2 journalling 1247 * where the running transaction has to wait for all handles to be 1248 * dropped to commit that transaction and also acquiring a handle may 1249 * require transaction commit to finish. 1250 */ 1251 struct lockdep_map j_trans_commit_map; 1252 #endif 1253 1254 /** 1255 * @j_fc_cleanup_callback: 1256 * 1257 * Clean-up after fast commit or full commit. JBD2 calls this function 1258 * after every commit operation. 1259 */ 1260 void (*j_fc_cleanup_callback)(struct journal_s *journal, int); 1261 1262 /** 1263 * @j_fc_replay_callback: 1264 * 1265 * File-system specific function that performs replay of a fast 1266 * commit. JBD2 calls this function for each fast commit block found in 1267 * the journal. This function should return JBD2_FC_REPLAY_CONTINUE 1268 * to indicate that the block was processed correctly and more fast 1269 * commit replay should continue. Return value of JBD2_FC_REPLAY_STOP 1270 * indicates the end of replay (no more blocks remaining). A negative 1271 * return value indicates error. 1272 */ 1273 int (*j_fc_replay_callback)(struct journal_s *journal, 1274 struct buffer_head *bh, 1275 enum passtype pass, int off, 1276 tid_t expected_commit_id); 1277 }; 1278 1279 #define jbd2_might_wait_for_commit(j) \ 1280 do { \ 1281 rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \ 1282 rwsem_release(&j->j_trans_commit_map, _THIS_IP_); \ 1283 } while (0) 1284 1285 /* journal feature predicate functions */ 1286 #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \ 1287 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1288 { \ 1289 return ((j)->j_format_version >= 2 && \ 1290 ((j)->j_superblock->s_feature_compat & \ 1291 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \ 1292 } \ 1293 static inline void jbd2_set_feature_##name(journal_t *j) \ 1294 { \ 1295 (j)->j_superblock->s_feature_compat |= \ 1296 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1297 } \ 1298 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1299 { \ 1300 (j)->j_superblock->s_feature_compat &= \ 1301 ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \ 1302 } 1303 1304 #define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \ 1305 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1306 { \ 1307 return ((j)->j_format_version >= 2 && \ 1308 ((j)->j_superblock->s_feature_ro_compat & \ 1309 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \ 1310 } \ 1311 static inline void jbd2_set_feature_##name(journal_t *j) \ 1312 { \ 1313 (j)->j_superblock->s_feature_ro_compat |= \ 1314 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1315 } \ 1316 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1317 { \ 1318 (j)->j_superblock->s_feature_ro_compat &= \ 1319 ~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \ 1320 } 1321 1322 #define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \ 1323 static inline bool jbd2_has_feature_##name(journal_t *j) \ 1324 { \ 1325 return ((j)->j_format_version >= 2 && \ 1326 ((j)->j_superblock->s_feature_incompat & \ 1327 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \ 1328 } \ 1329 static inline void jbd2_set_feature_##name(journal_t *j) \ 1330 { \ 1331 (j)->j_superblock->s_feature_incompat |= \ 1332 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1333 } \ 1334 static inline void jbd2_clear_feature_##name(journal_t *j) \ 1335 { \ 1336 (j)->j_superblock->s_feature_incompat &= \ 1337 ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \ 1338 } 1339 1340 JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM) 1341 1342 JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE) 1343 JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT) 1344 JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT) 1345 JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2) 1346 JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3) 1347 JBD2_FEATURE_INCOMPAT_FUNCS(fast_commit, FAST_COMMIT) 1348 1349 /* 1350 * Journal flag definitions 1351 */ 1352 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */ 1353 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */ 1354 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */ 1355 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */ 1356 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */ 1357 #define JBD2_BARRIER 0x020 /* Use IDE barriers */ 1358 #define JBD2_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file 1359 * data write error in ordered 1360 * mode */ 1361 #define JBD2_FAST_COMMIT_ONGOING 0x100 /* Fast commit is ongoing */ 1362 #define JBD2_FULL_COMMIT_ONGOING 0x200 /* Full commit is ongoing */ 1363 1364 /* 1365 * Function declarations for the journaling transaction and buffer 1366 * management 1367 */ 1368 1369 /* Filing buffers */ 1370 extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *); 1371 extern bool __jbd2_journal_refile_buffer(struct journal_head *); 1372 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *); 1373 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1374 extern void __journal_free_buffer(struct journal_head *bh); 1375 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int); 1376 extern void __journal_clean_data_list(transaction_t *transaction); 1377 static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh) 1378 { 1379 list_add_tail(&bh->b_assoc_buffers, head); 1380 } 1381 static inline void jbd2_unfile_log_bh(struct buffer_head *bh) 1382 { 1383 list_del_init(&bh->b_assoc_buffers); 1384 } 1385 1386 /* Log buffer allocation */ 1387 struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int); 1388 void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *); 1389 int jbd2_journal_next_log_block(journal_t *, unsigned long long *); 1390 int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, 1391 unsigned long *block); 1392 int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1393 void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block); 1394 1395 /* Commit management */ 1396 extern void jbd2_journal_commit_transaction(journal_t *); 1397 1398 /* Checkpoint list management */ 1399 void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy); 1400 int __jbd2_journal_remove_checkpoint(struct journal_head *); 1401 void jbd2_journal_destroy_checkpoint(journal_t *journal); 1402 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *); 1403 1404 1405 /* 1406 * Triggers 1407 */ 1408 1409 struct jbd2_buffer_trigger_type { 1410 /* 1411 * Fired a the moment data to write to the journal are known to be 1412 * stable - so either at the moment b_frozen_data is created or just 1413 * before a buffer is written to the journal. mapped_data is a mapped 1414 * buffer that is the frozen data for commit. 1415 */ 1416 void (*t_frozen)(struct jbd2_buffer_trigger_type *type, 1417 struct buffer_head *bh, void *mapped_data, 1418 size_t size); 1419 1420 /* 1421 * Fired during journal abort for dirty buffers that will not be 1422 * committed. 1423 */ 1424 void (*t_abort)(struct jbd2_buffer_trigger_type *type, 1425 struct buffer_head *bh); 1426 }; 1427 1428 extern void jbd2_buffer_frozen_trigger(struct journal_head *jh, 1429 void *mapped_data, 1430 struct jbd2_buffer_trigger_type *triggers); 1431 extern void jbd2_buffer_abort_trigger(struct journal_head *jh, 1432 struct jbd2_buffer_trigger_type *triggers); 1433 1434 /* Buffer IO */ 1435 extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction, 1436 struct journal_head *jh_in, 1437 struct buffer_head **bh_out, 1438 sector_t blocknr); 1439 1440 /* Transaction locking */ 1441 extern void __wait_on_journal (journal_t *); 1442 1443 /* Transaction cache support */ 1444 extern void jbd2_journal_destroy_transaction_cache(void); 1445 extern int __init jbd2_journal_init_transaction_cache(void); 1446 extern void jbd2_journal_free_transaction(transaction_t *); 1447 1448 /* 1449 * Journal locking. 1450 * 1451 * We need to lock the journal during transaction state changes so that nobody 1452 * ever tries to take a handle on the running transaction while we are in the 1453 * middle of moving it to the commit phase. j_state_lock does this. 1454 * 1455 * Note that the locking is completely interrupt unsafe. We never touch 1456 * journal structures from interrupts. 1457 */ 1458 1459 static inline handle_t *journal_current_handle(void) 1460 { 1461 return current->journal_info; 1462 } 1463 1464 /* The journaling code user interface: 1465 * 1466 * Create and destroy handles 1467 * Register buffer modifications against the current transaction. 1468 */ 1469 1470 extern handle_t *jbd2_journal_start(journal_t *, int nblocks); 1471 extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks, 1472 int revoke_records, gfp_t gfp_mask, 1473 unsigned int type, unsigned int line_no); 1474 extern int jbd2_journal_restart(handle_t *, int nblocks); 1475 extern int jbd2__journal_restart(handle_t *, int nblocks, 1476 int revoke_records, gfp_t gfp_mask); 1477 extern int jbd2_journal_start_reserved(handle_t *handle, 1478 unsigned int type, unsigned int line_no); 1479 extern void jbd2_journal_free_reserved(handle_t *handle); 1480 extern int jbd2_journal_extend(handle_t *handle, int nblocks, 1481 int revoke_records); 1482 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *); 1483 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *); 1484 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *); 1485 void jbd2_journal_set_triggers(struct buffer_head *, 1486 struct jbd2_buffer_trigger_type *type); 1487 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *); 1488 extern int jbd2_journal_forget (handle_t *, struct buffer_head *); 1489 extern int jbd2_journal_invalidatepage(journal_t *, 1490 struct page *, unsigned int, unsigned int); 1491 extern int jbd2_journal_try_to_free_buffers(journal_t *journal, struct page *page); 1492 extern int jbd2_journal_stop(handle_t *); 1493 extern int jbd2_journal_flush (journal_t *); 1494 extern void jbd2_journal_lock_updates (journal_t *); 1495 extern void jbd2_journal_unlock_updates (journal_t *); 1496 1497 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev, 1498 struct block_device *fs_dev, 1499 unsigned long long start, int len, int bsize); 1500 extern journal_t * jbd2_journal_init_inode (struct inode *); 1501 extern int jbd2_journal_update_format (journal_t *); 1502 extern int jbd2_journal_check_used_features 1503 (journal_t *, unsigned long, unsigned long, unsigned long); 1504 extern int jbd2_journal_check_available_features 1505 (journal_t *, unsigned long, unsigned long, unsigned long); 1506 extern int jbd2_journal_set_features 1507 (journal_t *, unsigned long, unsigned long, unsigned long); 1508 extern void jbd2_journal_clear_features 1509 (journal_t *, unsigned long, unsigned long, unsigned long); 1510 extern int jbd2_journal_load (journal_t *journal); 1511 extern int jbd2_journal_destroy (journal_t *); 1512 extern int jbd2_journal_recover (journal_t *journal); 1513 extern int jbd2_journal_wipe (journal_t *, int); 1514 extern int jbd2_journal_skip_recovery (journal_t *); 1515 extern void jbd2_journal_update_sb_errno(journal_t *); 1516 extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t, 1517 unsigned long, int); 1518 extern void jbd2_journal_abort (journal_t *, int); 1519 extern int jbd2_journal_errno (journal_t *); 1520 extern void jbd2_journal_ack_err (journal_t *); 1521 extern int jbd2_journal_clear_err (journal_t *); 1522 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *); 1523 extern int jbd2_journal_force_commit(journal_t *); 1524 extern int jbd2_journal_force_commit_nested(journal_t *); 1525 extern int jbd2_journal_inode_ranged_write(handle_t *handle, 1526 struct jbd2_inode *inode, loff_t start_byte, 1527 loff_t length); 1528 extern int jbd2_journal_inode_ranged_wait(handle_t *handle, 1529 struct jbd2_inode *inode, loff_t start_byte, 1530 loff_t length); 1531 extern int jbd2_journal_submit_inode_data_buffers( 1532 struct jbd2_inode *jinode); 1533 extern int jbd2_journal_finish_inode_data_buffers( 1534 struct jbd2_inode *jinode); 1535 extern int jbd2_journal_begin_ordered_truncate(journal_t *journal, 1536 struct jbd2_inode *inode, loff_t new_size); 1537 extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode); 1538 extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode); 1539 1540 /* 1541 * journal_head management 1542 */ 1543 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh); 1544 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh); 1545 void jbd2_journal_put_journal_head(struct journal_head *jh); 1546 1547 /* 1548 * handle management 1549 */ 1550 extern struct kmem_cache *jbd2_handle_cache; 1551 1552 static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags) 1553 { 1554 return kmem_cache_zalloc(jbd2_handle_cache, gfp_flags); 1555 } 1556 1557 static inline void jbd2_free_handle(handle_t *handle) 1558 { 1559 kmem_cache_free(jbd2_handle_cache, handle); 1560 } 1561 1562 /* 1563 * jbd2_inode management (optional, for those file systems that want to use 1564 * dynamically allocated jbd2_inode structures) 1565 */ 1566 extern struct kmem_cache *jbd2_inode_cache; 1567 1568 static inline struct jbd2_inode *jbd2_alloc_inode(gfp_t gfp_flags) 1569 { 1570 return kmem_cache_alloc(jbd2_inode_cache, gfp_flags); 1571 } 1572 1573 static inline void jbd2_free_inode(struct jbd2_inode *jinode) 1574 { 1575 kmem_cache_free(jbd2_inode_cache, jinode); 1576 } 1577 1578 /* Primary revoke support */ 1579 #define JOURNAL_REVOKE_DEFAULT_HASH 256 1580 extern int jbd2_journal_init_revoke(journal_t *, int); 1581 extern void jbd2_journal_destroy_revoke_record_cache(void); 1582 extern void jbd2_journal_destroy_revoke_table_cache(void); 1583 extern int __init jbd2_journal_init_revoke_record_cache(void); 1584 extern int __init jbd2_journal_init_revoke_table_cache(void); 1585 1586 extern void jbd2_journal_destroy_revoke(journal_t *); 1587 extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *); 1588 extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *); 1589 extern void jbd2_journal_write_revoke_records(transaction_t *transaction, 1590 struct list_head *log_bufs); 1591 1592 /* Recovery revoke support */ 1593 extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t); 1594 extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t); 1595 extern void jbd2_journal_clear_revoke(journal_t *); 1596 extern void jbd2_journal_switch_revoke_table(journal_t *journal); 1597 extern void jbd2_clear_buffer_revoked_flags(journal_t *journal); 1598 1599 /* 1600 * The log thread user interface: 1601 * 1602 * Request space in the current transaction, and force transaction commit 1603 * transitions on demand. 1604 */ 1605 1606 int jbd2_log_start_commit(journal_t *journal, tid_t tid); 1607 int __jbd2_log_start_commit(journal_t *journal, tid_t tid); 1608 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid); 1609 int jbd2_log_wait_commit(journal_t *journal, tid_t tid); 1610 int jbd2_transaction_committed(journal_t *journal, tid_t tid); 1611 int jbd2_complete_transaction(journal_t *journal, tid_t tid); 1612 int jbd2_log_do_checkpoint(journal_t *journal); 1613 int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid); 1614 1615 void __jbd2_log_wait_for_space(journal_t *journal); 1616 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *); 1617 extern int jbd2_cleanup_journal_tail(journal_t *); 1618 1619 /* Fast commit related APIs */ 1620 int jbd2_fc_begin_commit(journal_t *journal, tid_t tid); 1621 int jbd2_fc_end_commit(journal_t *journal); 1622 int jbd2_fc_end_commit_fallback(journal_t *journal); 1623 int jbd2_fc_get_buf(journal_t *journal, struct buffer_head **bh_out); 1624 int jbd2_submit_inode_data(struct jbd2_inode *jinode); 1625 int jbd2_wait_inode_data(journal_t *journal, struct jbd2_inode *jinode); 1626 int jbd2_fc_wait_bufs(journal_t *journal, int num_blks); 1627 int jbd2_fc_release_bufs(journal_t *journal); 1628 1629 static inline int jbd2_journal_get_max_txn_bufs(journal_t *journal) 1630 { 1631 return (journal->j_total_len - journal->j_fc_wbufsize) / 4; 1632 } 1633 1634 /* 1635 * is_journal_abort 1636 * 1637 * Simple test wrapper function to test the JBD2_ABORT state flag. This 1638 * bit, when set, indicates that we have had a fatal error somewhere, 1639 * either inside the journaling layer or indicated to us by the client 1640 * (eg. ext3), and that we and should not commit any further 1641 * transactions. 1642 */ 1643 1644 static inline int is_journal_aborted(journal_t *journal) 1645 { 1646 return journal->j_flags & JBD2_ABORT; 1647 } 1648 1649 static inline int is_handle_aborted(handle_t *handle) 1650 { 1651 if (handle->h_aborted || !handle->h_transaction) 1652 return 1; 1653 return is_journal_aborted(handle->h_transaction->t_journal); 1654 } 1655 1656 static inline void jbd2_journal_abort_handle(handle_t *handle) 1657 { 1658 handle->h_aborted = 1; 1659 } 1660 1661 #endif /* __KERNEL__ */ 1662 1663 /* Comparison functions for transaction IDs: perform comparisons using 1664 * modulo arithmetic so that they work over sequence number wraps. */ 1665 1666 static inline int tid_gt(tid_t x, tid_t y) 1667 { 1668 int difference = (x - y); 1669 return (difference > 0); 1670 } 1671 1672 static inline int tid_geq(tid_t x, tid_t y) 1673 { 1674 int difference = (x - y); 1675 return (difference >= 0); 1676 } 1677 1678 extern int jbd2_journal_blocks_per_page(struct inode *inode); 1679 extern size_t journal_tag_bytes(journal_t *journal); 1680 1681 static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j) 1682 { 1683 return jbd2_has_feature_csum2(j) || jbd2_has_feature_csum3(j); 1684 } 1685 1686 static inline int jbd2_journal_has_csum_v2or3(journal_t *journal) 1687 { 1688 WARN_ON_ONCE(jbd2_journal_has_csum_v2or3_feature(journal) && 1689 journal->j_chksum_driver == NULL); 1690 1691 return journal->j_chksum_driver != NULL; 1692 } 1693 1694 /* 1695 * Return number of free blocks in the log. Must be called under j_state_lock. 1696 */ 1697 static inline unsigned long jbd2_log_space_left(journal_t *journal) 1698 { 1699 /* Allow for rounding errors */ 1700 long free = journal->j_free - 32; 1701 1702 if (journal->j_committing_transaction) { 1703 free -= atomic_read(&journal-> 1704 j_committing_transaction->t_outstanding_credits); 1705 } 1706 return max_t(long, free, 0); 1707 } 1708 1709 /* 1710 * Definitions which augment the buffer_head layer 1711 */ 1712 1713 /* journaling buffer types */ 1714 #define BJ_None 0 /* Not journaled */ 1715 #define BJ_Metadata 1 /* Normal journaled metadata */ 1716 #define BJ_Forget 2 /* Buffer superseded by this transaction */ 1717 #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */ 1718 #define BJ_Reserved 4 /* Buffer is reserved for access by journal */ 1719 #define BJ_Types 5 1720 1721 extern int jbd_blocks_per_page(struct inode *inode); 1722 1723 /* JBD uses a CRC32 checksum */ 1724 #define JBD_MAX_CHECKSUM_SIZE 4 1725 1726 static inline u32 jbd2_chksum(journal_t *journal, u32 crc, 1727 const void *address, unsigned int length) 1728 { 1729 struct { 1730 struct shash_desc shash; 1731 char ctx[JBD_MAX_CHECKSUM_SIZE]; 1732 } desc; 1733 int err; 1734 1735 BUG_ON(crypto_shash_descsize(journal->j_chksum_driver) > 1736 JBD_MAX_CHECKSUM_SIZE); 1737 1738 desc.shash.tfm = journal->j_chksum_driver; 1739 *(u32 *)desc.ctx = crc; 1740 1741 err = crypto_shash_update(&desc.shash, address, length); 1742 BUG_ON(err); 1743 1744 return *(u32 *)desc.ctx; 1745 } 1746 1747 /* Return most recent uncommitted transaction */ 1748 static inline tid_t jbd2_get_latest_transaction(journal_t *journal) 1749 { 1750 tid_t tid; 1751 1752 read_lock(&journal->j_state_lock); 1753 tid = journal->j_commit_request; 1754 if (journal->j_running_transaction) 1755 tid = journal->j_running_transaction->t_tid; 1756 read_unlock(&journal->j_state_lock); 1757 return tid; 1758 } 1759 1760 static inline int jbd2_handle_buffer_credits(handle_t *handle) 1761 { 1762 journal_t *journal; 1763 1764 if (!handle->h_reserved) 1765 journal = handle->h_transaction->t_journal; 1766 else 1767 journal = handle->h_journal; 1768 1769 return handle->h_total_credits - 1770 DIV_ROUND_UP(handle->h_revoke_credits_requested, 1771 journal->j_revoke_records_per_block); 1772 } 1773 1774 #ifdef __KERNEL__ 1775 1776 #define buffer_trace_init(bh) do {} while (0) 1777 #define print_buffer_fields(bh) do {} while (0) 1778 #define print_buffer_trace(bh) do {} while (0) 1779 #define BUFFER_TRACE(bh, info) do {} while (0) 1780 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0) 1781 #define JBUFFER_TRACE(jh, info) do {} while (0) 1782 1783 #endif /* __KERNEL__ */ 1784 1785 #define EFSBADCRC EBADMSG /* Bad CRC detected */ 1786 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ 1787 1788 #endif /* _LINUX_JBD2_H */ 1789