Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/include/linux/jbd.h |
| 3 | * |
| 4 | * Written by Stephen C. Tweedie <sct@redhat.com> |
| 5 | * |
| 6 | * Copyright 1998-2000 Red Hat, Inc --- All Rights Reserved |
| 7 | * |
| 8 | * This file is part of the Linux kernel and is made available under |
| 9 | * the terms of the GNU General Public License, version 2, or at your |
| 10 | * option, any later version, incorporated herein by reference. |
| 11 | * |
| 12 | * Definitions for transaction data structures for the buffer cache |
| 13 | * filesystem journaling support. |
| 14 | */ |
| 15 | |
| 16 | #ifndef _LINUX_JBD_H |
| 17 | #define _LINUX_JBD_H |
| 18 | |
| 19 | #if defined(CONFIG_JBD) || defined(CONFIG_JBD_MODULE) || !defined(__KERNEL__) |
| 20 | |
| 21 | /* Allow this file to be included directly into e2fsprogs */ |
| 22 | #ifndef __KERNEL__ |
| 23 | #include "jfs_compat.h" |
| 24 | #define JFS_DEBUG |
| 25 | #define jfs_debug jbd_debug |
| 26 | #else |
| 27 | |
| 28 | #include <linux/buffer_head.h> |
| 29 | #include <linux/journal-head.h> |
| 30 | #include <linux/stddef.h> |
| 31 | #include <asm/semaphore.h> |
| 32 | #endif |
| 33 | |
| 34 | #define journal_oom_retry 1 |
| 35 | |
| 36 | /* |
| 37 | * Define JBD_PARANIOD_IOFAIL to cause a kernel BUG() if ext3 finds |
| 38 | * certain classes of error which can occur due to failed IOs. Under |
| 39 | * normal use we want ext3 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 JBD_PARANOID_IOFAIL |
| 44 | |
| 45 | /* |
| 46 | * The default maximum commit age, in seconds. |
| 47 | */ |
| 48 | #define JBD_DEFAULT_MAX_COMMIT_AGE 5 |
| 49 | |
| 50 | #ifdef CONFIG_JBD_DEBUG |
| 51 | /* |
| 52 | * Define JBD_EXPENSIVE_CHECKING to enable more expensive internal |
| 53 | * consistency checks. By default we don't do this unless |
| 54 | * CONFIG_JBD_DEBUG is on. |
| 55 | */ |
| 56 | #define JBD_EXPENSIVE_CHECKING |
| 57 | extern int journal_enable_debug; |
| 58 | |
| 59 | #define jbd_debug(n, f, a...) \ |
| 60 | do { \ |
| 61 | if ((n) <= journal_enable_debug) { \ |
| 62 | printk (KERN_DEBUG "(%s, %d): %s: ", \ |
| 63 | __FILE__, __LINE__, __FUNCTION__); \ |
| 64 | printk (f, ## a); \ |
| 65 | } \ |
| 66 | } while (0) |
| 67 | #else |
| 68 | #define jbd_debug(f, a...) /**/ |
| 69 | #endif |
| 70 | |
| 71 | extern void * __jbd_kmalloc (const char *where, size_t size, int flags, int retry); |
| 72 | #define jbd_kmalloc(size, flags) \ |
| 73 | __jbd_kmalloc(__FUNCTION__, (size), (flags), journal_oom_retry) |
| 74 | #define jbd_rep_kmalloc(size, flags) \ |
| 75 | __jbd_kmalloc(__FUNCTION__, (size), (flags), 1) |
| 76 | |
| 77 | #define JFS_MIN_JOURNAL_BLOCKS 1024 |
| 78 | |
| 79 | #ifdef __KERNEL__ |
| 80 | |
| 81 | /** |
| 82 | * typedef handle_t - The handle_t type represents a single atomic update being performed by some process. |
| 83 | * |
| 84 | * All filesystem modifications made by the process go |
| 85 | * through this handle. Recursive operations (such as quota operations) |
| 86 | * are gathered into a single update. |
| 87 | * |
| 88 | * The buffer credits field is used to account for journaled buffers |
| 89 | * being modified by the running process. To ensure that there is |
| 90 | * enough log space for all outstanding operations, we need to limit the |
| 91 | * number of outstanding buffers possible at any time. When the |
| 92 | * operation completes, any buffer credits not used are credited back to |
| 93 | * the transaction, so that at all times we know how many buffers the |
| 94 | * outstanding updates on a transaction might possibly touch. |
| 95 | * |
| 96 | * This is an opaque datatype. |
| 97 | **/ |
| 98 | typedef struct handle_s handle_t; /* Atomic operation type */ |
| 99 | |
| 100 | |
| 101 | /** |
| 102 | * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem. |
| 103 | * |
| 104 | * journal_t is linked to from the fs superblock structure. |
| 105 | * |
| 106 | * We use the journal_t to keep track of all outstanding transaction |
| 107 | * activity on the filesystem, and to manage the state of the log |
| 108 | * writing process. |
| 109 | * |
| 110 | * This is an opaque datatype. |
| 111 | **/ |
| 112 | typedef struct journal_s journal_t; /* Journal control structure */ |
| 113 | #endif |
| 114 | |
| 115 | /* |
| 116 | * Internal structures used by the logging mechanism: |
| 117 | */ |
| 118 | |
| 119 | #define JFS_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */ |
| 120 | |
| 121 | /* |
| 122 | * On-disk structures |
| 123 | */ |
| 124 | |
| 125 | /* |
| 126 | * Descriptor block types: |
| 127 | */ |
| 128 | |
| 129 | #define JFS_DESCRIPTOR_BLOCK 1 |
| 130 | #define JFS_COMMIT_BLOCK 2 |
| 131 | #define JFS_SUPERBLOCK_V1 3 |
| 132 | #define JFS_SUPERBLOCK_V2 4 |
| 133 | #define JFS_REVOKE_BLOCK 5 |
| 134 | |
| 135 | /* |
| 136 | * Standard header for all descriptor blocks: |
| 137 | */ |
| 138 | typedef struct journal_header_s |
| 139 | { |
| 140 | __be32 h_magic; |
| 141 | __be32 h_blocktype; |
| 142 | __be32 h_sequence; |
| 143 | } journal_header_t; |
| 144 | |
| 145 | |
| 146 | /* |
| 147 | * The block tag: used to describe a single buffer in the journal |
| 148 | */ |
| 149 | typedef struct journal_block_tag_s |
| 150 | { |
| 151 | __be32 t_blocknr; /* The on-disk block number */ |
| 152 | __be32 t_flags; /* See below */ |
| 153 | } journal_block_tag_t; |
| 154 | |
| 155 | /* |
| 156 | * The revoke descriptor: used on disk to describe a series of blocks to |
| 157 | * be revoked from the log |
| 158 | */ |
| 159 | typedef struct journal_revoke_header_s |
| 160 | { |
| 161 | journal_header_t r_header; |
| 162 | __be32 r_count; /* Count of bytes used in the block */ |
| 163 | } journal_revoke_header_t; |
| 164 | |
| 165 | |
| 166 | /* Definitions for the journal tag flags word: */ |
| 167 | #define JFS_FLAG_ESCAPE 1 /* on-disk block is escaped */ |
| 168 | #define JFS_FLAG_SAME_UUID 2 /* block has same uuid as previous */ |
| 169 | #define JFS_FLAG_DELETED 4 /* block deleted by this transaction */ |
| 170 | #define JFS_FLAG_LAST_TAG 8 /* last tag in this descriptor block */ |
| 171 | |
| 172 | |
| 173 | /* |
| 174 | * The journal superblock. All fields are in big-endian byte order. |
| 175 | */ |
| 176 | typedef struct journal_superblock_s |
| 177 | { |
| 178 | /* 0x0000 */ |
| 179 | journal_header_t s_header; |
| 180 | |
| 181 | /* 0x000C */ |
| 182 | /* Static information describing the journal */ |
| 183 | __be32 s_blocksize; /* journal device blocksize */ |
| 184 | __be32 s_maxlen; /* total blocks in journal file */ |
| 185 | __be32 s_first; /* first block of log information */ |
| 186 | |
| 187 | /* 0x0018 */ |
| 188 | /* Dynamic information describing the current state of the log */ |
| 189 | __be32 s_sequence; /* first commit ID expected in log */ |
| 190 | __be32 s_start; /* blocknr of start of log */ |
| 191 | |
| 192 | /* 0x0020 */ |
| 193 | /* Error value, as set by journal_abort(). */ |
| 194 | __be32 s_errno; |
| 195 | |
| 196 | /* 0x0024 */ |
| 197 | /* Remaining fields are only valid in a version-2 superblock */ |
| 198 | __be32 s_feature_compat; /* compatible feature set */ |
| 199 | __be32 s_feature_incompat; /* incompatible feature set */ |
| 200 | __be32 s_feature_ro_compat; /* readonly-compatible feature set */ |
| 201 | /* 0x0030 */ |
| 202 | __u8 s_uuid[16]; /* 128-bit uuid for journal */ |
| 203 | |
| 204 | /* 0x0040 */ |
| 205 | __be32 s_nr_users; /* Nr of filesystems sharing log */ |
| 206 | |
| 207 | __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/ |
| 208 | |
| 209 | /* 0x0048 */ |
| 210 | __be32 s_max_transaction; /* Limit of journal blocks per trans.*/ |
| 211 | __be32 s_max_trans_data; /* Limit of data blocks per trans. */ |
| 212 | |
| 213 | /* 0x0050 */ |
| 214 | __u32 s_padding[44]; |
| 215 | |
| 216 | /* 0x0100 */ |
| 217 | __u8 s_users[16*48]; /* ids of all fs'es sharing the log */ |
| 218 | /* 0x0400 */ |
| 219 | } journal_superblock_t; |
| 220 | |
| 221 | #define JFS_HAS_COMPAT_FEATURE(j,mask) \ |
| 222 | ((j)->j_format_version >= 2 && \ |
| 223 | ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask)))) |
| 224 | #define JFS_HAS_RO_COMPAT_FEATURE(j,mask) \ |
| 225 | ((j)->j_format_version >= 2 && \ |
| 226 | ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask)))) |
| 227 | #define JFS_HAS_INCOMPAT_FEATURE(j,mask) \ |
| 228 | ((j)->j_format_version >= 2 && \ |
| 229 | ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask)))) |
| 230 | |
| 231 | #define JFS_FEATURE_INCOMPAT_REVOKE 0x00000001 |
| 232 | |
| 233 | /* Features known to this kernel version: */ |
| 234 | #define JFS_KNOWN_COMPAT_FEATURES 0 |
| 235 | #define JFS_KNOWN_ROCOMPAT_FEATURES 0 |
| 236 | #define JFS_KNOWN_INCOMPAT_FEATURES JFS_FEATURE_INCOMPAT_REVOKE |
| 237 | |
| 238 | #ifdef __KERNEL__ |
| 239 | |
| 240 | #include <linux/fs.h> |
| 241 | #include <linux/sched.h> |
| 242 | #include <asm/bug.h> |
| 243 | |
| 244 | #define JBD_ASSERTIONS |
| 245 | #ifdef JBD_ASSERTIONS |
| 246 | #define J_ASSERT(assert) \ |
| 247 | do { \ |
| 248 | if (!(assert)) { \ |
| 249 | printk (KERN_EMERG \ |
| 250 | "Assertion failure in %s() at %s:%d: \"%s\"\n", \ |
| 251 | __FUNCTION__, __FILE__, __LINE__, # assert); \ |
| 252 | BUG(); \ |
| 253 | } \ |
| 254 | } while (0) |
| 255 | |
| 256 | #if defined(CONFIG_BUFFER_DEBUG) |
| 257 | void buffer_assertion_failure(struct buffer_head *bh); |
| 258 | #define J_ASSERT_BH(bh, expr) \ |
| 259 | do { \ |
| 260 | if (!(expr)) \ |
| 261 | buffer_assertion_failure(bh); \ |
| 262 | J_ASSERT(expr); \ |
| 263 | } while (0) |
| 264 | #define J_ASSERT_JH(jh, expr) J_ASSERT_BH(jh2bh(jh), expr) |
| 265 | #else |
| 266 | #define J_ASSERT_BH(bh, expr) J_ASSERT(expr) |
| 267 | #define J_ASSERT_JH(jh, expr) J_ASSERT(expr) |
| 268 | #endif |
| 269 | |
| 270 | #else |
| 271 | #define J_ASSERT(assert) do { } while (0) |
| 272 | #endif /* JBD_ASSERTIONS */ |
| 273 | |
| 274 | #if defined(JBD_PARANOID_IOFAIL) |
| 275 | #define J_EXPECT(expr, why...) J_ASSERT(expr) |
| 276 | #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr) |
| 277 | #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr) |
| 278 | #else |
| 279 | #define __journal_expect(expr, why...) \ |
| 280 | ({ \ |
| 281 | int val = (expr); \ |
| 282 | if (!val) { \ |
| 283 | printk(KERN_ERR \ |
| 284 | "EXT3-fs unexpected failure: %s;\n",# expr); \ |
| 285 | printk(KERN_ERR why "\n"); \ |
| 286 | } \ |
| 287 | val; \ |
| 288 | }) |
| 289 | #define J_EXPECT(expr, why...) __journal_expect(expr, ## why) |
| 290 | #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why) |
| 291 | #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why) |
| 292 | #endif |
| 293 | |
| 294 | enum jbd_state_bits { |
| 295 | BH_JBD /* Has an attached ext3 journal_head */ |
| 296 | = BH_PrivateStart, |
| 297 | BH_JWrite, /* Being written to log (@@@ DEBUGGING) */ |
| 298 | BH_Freed, /* Has been freed (truncated) */ |
| 299 | BH_Revoked, /* Has been revoked from the log */ |
| 300 | BH_RevokeValid, /* Revoked flag is valid */ |
| 301 | BH_JBDDirty, /* Is dirty but journaled */ |
| 302 | BH_State, /* Pins most journal_head state */ |
| 303 | BH_JournalHead, /* Pins bh->b_private and jh->b_bh */ |
| 304 | BH_Unshadow, /* Dummy bit, for BJ_Shadow wakeup filtering */ |
| 305 | }; |
| 306 | |
| 307 | BUFFER_FNS(JBD, jbd) |
| 308 | BUFFER_FNS(JWrite, jwrite) |
| 309 | BUFFER_FNS(JBDDirty, jbddirty) |
| 310 | TAS_BUFFER_FNS(JBDDirty, jbddirty) |
| 311 | BUFFER_FNS(Revoked, revoked) |
| 312 | TAS_BUFFER_FNS(Revoked, revoked) |
| 313 | BUFFER_FNS(RevokeValid, revokevalid) |
| 314 | TAS_BUFFER_FNS(RevokeValid, revokevalid) |
| 315 | BUFFER_FNS(Freed, freed) |
| 316 | |
| 317 | static inline struct buffer_head *jh2bh(struct journal_head *jh) |
| 318 | { |
| 319 | return jh->b_bh; |
| 320 | } |
| 321 | |
| 322 | static inline struct journal_head *bh2jh(struct buffer_head *bh) |
| 323 | { |
| 324 | return bh->b_private; |
| 325 | } |
| 326 | |
| 327 | static inline void jbd_lock_bh_state(struct buffer_head *bh) |
| 328 | { |
| 329 | bit_spin_lock(BH_State, &bh->b_state); |
| 330 | } |
| 331 | |
| 332 | static inline int jbd_trylock_bh_state(struct buffer_head *bh) |
| 333 | { |
| 334 | return bit_spin_trylock(BH_State, &bh->b_state); |
| 335 | } |
| 336 | |
| 337 | static inline int jbd_is_locked_bh_state(struct buffer_head *bh) |
| 338 | { |
| 339 | return bit_spin_is_locked(BH_State, &bh->b_state); |
| 340 | } |
| 341 | |
| 342 | static inline void jbd_unlock_bh_state(struct buffer_head *bh) |
| 343 | { |
| 344 | bit_spin_unlock(BH_State, &bh->b_state); |
| 345 | } |
| 346 | |
| 347 | static inline void jbd_lock_bh_journal_head(struct buffer_head *bh) |
| 348 | { |
| 349 | bit_spin_lock(BH_JournalHead, &bh->b_state); |
| 350 | } |
| 351 | |
| 352 | static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh) |
| 353 | { |
| 354 | bit_spin_unlock(BH_JournalHead, &bh->b_state); |
| 355 | } |
| 356 | |
| 357 | struct jbd_revoke_table_s; |
| 358 | |
| 359 | /** |
| 360 | * struct handle_s - The handle_s type is the concrete type associated with |
| 361 | * handle_t. |
| 362 | * @h_transaction: Which compound transaction is this update a part of? |
| 363 | * @h_buffer_credits: Number of remaining buffers we are allowed to dirty. |
| 364 | * @h_ref: Reference count on this handle |
| 365 | * @h_err: Field for caller's use to track errors through large fs operations |
| 366 | * @h_sync: flag for sync-on-close |
| 367 | * @h_jdata: flag to force data journaling |
| 368 | * @h_aborted: flag indicating fatal error on handle |
| 369 | **/ |
| 370 | |
| 371 | /* Docbook can't yet cope with the bit fields, but will leave the documentation |
| 372 | * in so it can be fixed later. |
| 373 | */ |
| 374 | |
| 375 | struct handle_s |
| 376 | { |
| 377 | /* Which compound transaction is this update a part of? */ |
| 378 | transaction_t *h_transaction; |
| 379 | |
| 380 | /* Number of remaining buffers we are allowed to dirty: */ |
| 381 | int h_buffer_credits; |
| 382 | |
| 383 | /* Reference count on this handle */ |
| 384 | int h_ref; |
| 385 | |
| 386 | /* Field for caller's use to track errors through large fs */ |
| 387 | /* operations */ |
| 388 | int h_err; |
| 389 | |
| 390 | /* Flags [no locking] */ |
| 391 | unsigned int h_sync: 1; /* sync-on-close */ |
| 392 | unsigned int h_jdata: 1; /* force data journaling */ |
| 393 | unsigned int h_aborted: 1; /* fatal error on handle */ |
| 394 | }; |
| 395 | |
| 396 | |
| 397 | /* The transaction_t type is the guts of the journaling mechanism. It |
| 398 | * tracks a compound transaction through its various states: |
| 399 | * |
| 400 | * RUNNING: accepting new updates |
| 401 | * LOCKED: Updates still running but we don't accept new ones |
| 402 | * RUNDOWN: Updates are tidying up but have finished requesting |
| 403 | * new buffers to modify (state not used for now) |
| 404 | * FLUSH: All updates complete, but we are still writing to disk |
| 405 | * COMMIT: All data on disk, writing commit record |
| 406 | * FINISHED: We still have to keep the transaction for checkpointing. |
| 407 | * |
| 408 | * The transaction keeps track of all of the buffers modified by a |
| 409 | * running transaction, and all of the buffers committed but not yet |
| 410 | * flushed to home for finished transactions. |
| 411 | */ |
| 412 | |
| 413 | /* |
| 414 | * Lock ranking: |
| 415 | * |
| 416 | * j_list_lock |
| 417 | * ->jbd_lock_bh_journal_head() (This is "innermost") |
| 418 | * |
| 419 | * j_state_lock |
| 420 | * ->jbd_lock_bh_state() |
| 421 | * |
| 422 | * jbd_lock_bh_state() |
| 423 | * ->j_list_lock |
| 424 | * |
| 425 | * j_state_lock |
| 426 | * ->t_handle_lock |
| 427 | * |
| 428 | * j_state_lock |
| 429 | * ->j_list_lock (journal_unmap_buffer) |
| 430 | * |
| 431 | */ |
| 432 | |
| 433 | struct transaction_s |
| 434 | { |
| 435 | /* Pointer to the journal for this transaction. [no locking] */ |
| 436 | journal_t *t_journal; |
| 437 | |
| 438 | /* Sequence number for this transaction [no locking] */ |
| 439 | tid_t t_tid; |
| 440 | |
| 441 | /* |
| 442 | * Transaction's current state |
| 443 | * [no locking - only kjournald alters this] |
| 444 | * FIXME: needs barriers |
| 445 | * KLUDGE: [use j_state_lock] |
| 446 | */ |
| 447 | enum { |
| 448 | T_RUNNING, |
| 449 | T_LOCKED, |
| 450 | T_RUNDOWN, |
| 451 | T_FLUSH, |
| 452 | T_COMMIT, |
| 453 | T_FINISHED |
| 454 | } t_state; |
| 455 | |
| 456 | /* |
| 457 | * Where in the log does this transaction's commit start? [no locking] |
| 458 | */ |
| 459 | unsigned long t_log_start; |
| 460 | |
| 461 | /* Number of buffers on the t_buffers list [j_list_lock] */ |
| 462 | int t_nr_buffers; |
| 463 | |
| 464 | /* |
| 465 | * Doubly-linked circular list of all buffers reserved but not yet |
| 466 | * modified by this transaction [j_list_lock] |
| 467 | */ |
| 468 | struct journal_head *t_reserved_list; |
| 469 | |
| 470 | /* |
| 471 | * Doubly-linked circular list of all buffers under writeout during |
| 472 | * commit [j_list_lock] |
| 473 | */ |
| 474 | struct journal_head *t_locked_list; |
| 475 | |
| 476 | /* |
| 477 | * Doubly-linked circular list of all metadata buffers owned by this |
| 478 | * transaction [j_list_lock] |
| 479 | */ |
| 480 | struct journal_head *t_buffers; |
| 481 | |
| 482 | /* |
| 483 | * Doubly-linked circular list of all data buffers still to be |
| 484 | * flushed before this transaction can be committed [j_list_lock] |
| 485 | */ |
| 486 | struct journal_head *t_sync_datalist; |
| 487 | |
| 488 | /* |
| 489 | * Doubly-linked circular list of all forget buffers (superseded |
| 490 | * buffers which we can un-checkpoint once this transaction commits) |
| 491 | * [j_list_lock] |
| 492 | */ |
| 493 | struct journal_head *t_forget; |
| 494 | |
| 495 | /* |
| 496 | * Doubly-linked circular list of all buffers still to be flushed before |
| 497 | * this transaction can be checkpointed. [j_list_lock] |
| 498 | */ |
| 499 | struct journal_head *t_checkpoint_list; |
| 500 | |
| 501 | /* |
| 502 | * Doubly-linked circular list of temporary buffers currently undergoing |
| 503 | * IO in the log [j_list_lock] |
| 504 | */ |
| 505 | struct journal_head *t_iobuf_list; |
| 506 | |
| 507 | /* |
| 508 | * Doubly-linked circular list of metadata buffers being shadowed by log |
| 509 | * IO. The IO buffers on the iobuf list and the shadow buffers on this |
| 510 | * list match each other one for one at all times. [j_list_lock] |
| 511 | */ |
| 512 | struct journal_head *t_shadow_list; |
| 513 | |
| 514 | /* |
| 515 | * Doubly-linked circular list of control buffers being written to the |
| 516 | * log. [j_list_lock] |
| 517 | */ |
| 518 | struct journal_head *t_log_list; |
| 519 | |
| 520 | /* |
| 521 | * Protects info related to handles |
| 522 | */ |
| 523 | spinlock_t t_handle_lock; |
| 524 | |
| 525 | /* |
| 526 | * Number of outstanding updates running on this transaction |
| 527 | * [t_handle_lock] |
| 528 | */ |
| 529 | int t_updates; |
| 530 | |
| 531 | /* |
| 532 | * Number of buffers reserved for use by all handles in this transaction |
| 533 | * handle but not yet modified. [t_handle_lock] |
| 534 | */ |
| 535 | int t_outstanding_credits; |
| 536 | |
| 537 | /* |
| 538 | * Forward and backward links for the circular list of all transactions |
| 539 | * awaiting checkpoint. [j_list_lock] |
| 540 | */ |
| 541 | transaction_t *t_cpnext, *t_cpprev; |
| 542 | |
| 543 | /* |
| 544 | * When will the transaction expire (become due for commit), in jiffies? |
| 545 | * [no locking] |
| 546 | */ |
| 547 | unsigned long t_expires; |
| 548 | |
| 549 | /* |
| 550 | * How many handles used this transaction? [t_handle_lock] |
| 551 | */ |
| 552 | int t_handle_count; |
| 553 | |
| 554 | }; |
| 555 | |
| 556 | /** |
| 557 | * struct journal_s - The journal_s type is the concrete type associated with |
| 558 | * journal_t. |
| 559 | * @j_flags: General journaling state flags |
| 560 | * @j_errno: Is there an outstanding uncleared error on the journal (from a |
| 561 | * prior abort)? |
| 562 | * @j_sb_buffer: First part of superblock buffer |
| 563 | * @j_superblock: Second part of superblock buffer |
| 564 | * @j_format_version: Version of the superblock format |
| 565 | * @j_state_lock: Protect the various scalars in the journal |
| 566 | * @j_barrier_count: Number of processes waiting to create a barrier lock |
| 567 | * @j_barrier: The barrier lock itself |
| 568 | * @j_running_transaction: The current running transaction.. |
| 569 | * @j_committing_transaction: the transaction we are pushing to disk |
| 570 | * @j_checkpoint_transactions: a linked circular list of all transactions |
| 571 | * waiting for checkpointing |
| 572 | * @j_wait_transaction_locked: Wait queue for waiting for a locked transaction |
| 573 | * to start committing, or for a barrier lock to be released |
| 574 | * @j_wait_logspace: Wait queue for waiting for checkpointing to complete |
| 575 | * @j_wait_done_commit: Wait queue for waiting for commit to complete |
| 576 | * @j_wait_checkpoint: Wait queue to trigger checkpointing |
| 577 | * @j_wait_commit: Wait queue to trigger commit |
| 578 | * @j_wait_updates: Wait queue to wait for updates to complete |
| 579 | * @j_checkpoint_sem: Semaphore for locking against concurrent checkpoints |
| 580 | * @j_head: Journal head - identifies the first unused block in the journal |
| 581 | * @j_tail: Journal tail - identifies the oldest still-used block in the |
| 582 | * journal. |
| 583 | * @j_free: Journal free - how many free blocks are there in the journal? |
| 584 | * @j_first: The block number of the first usable block |
| 585 | * @j_last: The block number one beyond the last usable block |
| 586 | * @j_dev: Device where we store the journal |
| 587 | * @j_blocksize: blocksize for the location where we store the journal. |
| 588 | * @j_blk_offset: starting block offset for into the device where we store the |
| 589 | * journal |
| 590 | * @j_fs_dev: Device which holds the client fs. For internal journal this will |
| 591 | * be equal to j_dev |
| 592 | * @j_maxlen: Total maximum capacity of the journal region on disk. |
| 593 | * @j_list_lock: Protects the buffer lists and internal buffer state. |
| 594 | * @j_inode: Optional inode where we store the journal. If present, all journal |
| 595 | * block numbers are mapped into this inode via bmap(). |
| 596 | * @j_tail_sequence: Sequence number of the oldest transaction in the log |
| 597 | * @j_transaction_sequence: Sequence number of the next transaction to grant |
| 598 | * @j_commit_sequence: Sequence number of the most recently committed |
| 599 | * transaction |
| 600 | * @j_commit_request: Sequence number of the most recent transaction wanting |
| 601 | * commit |
| 602 | * @j_uuid: Uuid of client object. |
| 603 | * @j_task: Pointer to the current commit thread for this journal |
| 604 | * @j_max_transaction_buffers: Maximum number of metadata buffers to allow in a |
| 605 | * single compound commit transaction |
| 606 | * @j_commit_interval: What is the maximum transaction lifetime before we begin |
| 607 | * a commit? |
| 608 | * @j_commit_timer: The timer used to wakeup the commit thread |
| 609 | * @j_revoke_lock: Protect the revoke table |
| 610 | * @j_revoke: The revoke table - maintains the list of revoked blocks in the |
| 611 | * current transaction. |
| 612 | * @j_revoke_table: alternate revoke tables for j_revoke |
| 613 | * @j_private: An opaque pointer to fs-private information. |
| 614 | */ |
| 615 | |
| 616 | struct journal_s |
| 617 | { |
| 618 | /* General journaling state flags [j_state_lock] */ |
| 619 | unsigned long j_flags; |
| 620 | |
| 621 | /* |
| 622 | * Is there an outstanding uncleared error on the journal (from a prior |
| 623 | * abort)? [j_state_lock] |
| 624 | */ |
| 625 | int j_errno; |
| 626 | |
| 627 | /* The superblock buffer */ |
| 628 | struct buffer_head *j_sb_buffer; |
| 629 | journal_superblock_t *j_superblock; |
| 630 | |
| 631 | /* Version of the superblock format */ |
| 632 | int j_format_version; |
| 633 | |
| 634 | /* |
| 635 | * Protect the various scalars in the journal |
| 636 | */ |
| 637 | spinlock_t j_state_lock; |
| 638 | |
| 639 | /* |
| 640 | * Number of processes waiting to create a barrier lock [j_state_lock] |
| 641 | */ |
| 642 | int j_barrier_count; |
| 643 | |
| 644 | /* The barrier lock itself */ |
| 645 | struct semaphore j_barrier; |
| 646 | |
| 647 | /* |
| 648 | * Transactions: The current running transaction... |
| 649 | * [j_state_lock] [caller holding open handle] |
| 650 | */ |
| 651 | transaction_t *j_running_transaction; |
| 652 | |
| 653 | /* |
| 654 | * the transaction we are pushing to disk |
| 655 | * [j_state_lock] [caller holding open handle] |
| 656 | */ |
| 657 | transaction_t *j_committing_transaction; |
| 658 | |
| 659 | /* |
| 660 | * ... and a linked circular list of all transactions waiting for |
| 661 | * checkpointing. [j_list_lock] |
| 662 | */ |
| 663 | transaction_t *j_checkpoint_transactions; |
| 664 | |
| 665 | /* |
| 666 | * Wait queue for waiting for a locked transaction to start committing, |
| 667 | * or for a barrier lock to be released |
| 668 | */ |
| 669 | wait_queue_head_t j_wait_transaction_locked; |
| 670 | |
| 671 | /* Wait queue for waiting for checkpointing to complete */ |
| 672 | wait_queue_head_t j_wait_logspace; |
| 673 | |
| 674 | /* Wait queue for waiting for commit to complete */ |
| 675 | wait_queue_head_t j_wait_done_commit; |
| 676 | |
| 677 | /* Wait queue to trigger checkpointing */ |
| 678 | wait_queue_head_t j_wait_checkpoint; |
| 679 | |
| 680 | /* Wait queue to trigger commit */ |
| 681 | wait_queue_head_t j_wait_commit; |
| 682 | |
| 683 | /* Wait queue to wait for updates to complete */ |
| 684 | wait_queue_head_t j_wait_updates; |
| 685 | |
| 686 | /* Semaphore for locking against concurrent checkpoints */ |
| 687 | struct semaphore j_checkpoint_sem; |
| 688 | |
| 689 | /* |
| 690 | * Journal head: identifies the first unused block in the journal. |
| 691 | * [j_state_lock] |
| 692 | */ |
| 693 | unsigned long j_head; |
| 694 | |
| 695 | /* |
| 696 | * Journal tail: identifies the oldest still-used block in the journal. |
| 697 | * [j_state_lock] |
| 698 | */ |
| 699 | unsigned long j_tail; |
| 700 | |
| 701 | /* |
| 702 | * Journal free: how many free blocks are there in the journal? |
| 703 | * [j_state_lock] |
| 704 | */ |
| 705 | unsigned long j_free; |
| 706 | |
| 707 | /* |
| 708 | * Journal start and end: the block numbers of the first usable block |
| 709 | * and one beyond the last usable block in the journal. [j_state_lock] |
| 710 | */ |
| 711 | unsigned long j_first; |
| 712 | unsigned long j_last; |
| 713 | |
| 714 | /* |
| 715 | * Device, blocksize and starting block offset for the location where we |
| 716 | * store the journal. |
| 717 | */ |
| 718 | struct block_device *j_dev; |
| 719 | int j_blocksize; |
| 720 | unsigned int j_blk_offset; |
| 721 | |
| 722 | /* |
| 723 | * Device which holds the client fs. For internal journal this will be |
| 724 | * equal to j_dev. |
| 725 | */ |
| 726 | struct block_device *j_fs_dev; |
| 727 | |
| 728 | /* Total maximum capacity of the journal region on disk. */ |
| 729 | unsigned int j_maxlen; |
| 730 | |
| 731 | /* |
| 732 | * Protects the buffer lists and internal buffer state. |
| 733 | */ |
| 734 | spinlock_t j_list_lock; |
| 735 | |
| 736 | /* Optional inode where we store the journal. If present, all */ |
| 737 | /* journal block numbers are mapped into this inode via */ |
| 738 | /* bmap(). */ |
| 739 | struct inode *j_inode; |
| 740 | |
| 741 | /* |
| 742 | * Sequence number of the oldest transaction in the log [j_state_lock] |
| 743 | */ |
| 744 | tid_t j_tail_sequence; |
| 745 | |
| 746 | /* |
| 747 | * Sequence number of the next transaction to grant [j_state_lock] |
| 748 | */ |
| 749 | tid_t j_transaction_sequence; |
| 750 | |
| 751 | /* |
| 752 | * Sequence number of the most recently committed transaction |
| 753 | * [j_state_lock]. |
| 754 | */ |
| 755 | tid_t j_commit_sequence; |
| 756 | |
| 757 | /* |
| 758 | * Sequence number of the most recent transaction wanting commit |
| 759 | * [j_state_lock] |
| 760 | */ |
| 761 | tid_t j_commit_request; |
| 762 | |
| 763 | /* |
| 764 | * Journal uuid: identifies the object (filesystem, LVM volume etc) |
| 765 | * backed by this journal. This will eventually be replaced by an array |
| 766 | * of uuids, allowing us to index multiple devices within a single |
| 767 | * journal and to perform atomic updates across them. |
| 768 | */ |
| 769 | __u8 j_uuid[16]; |
| 770 | |
| 771 | /* Pointer to the current commit thread for this journal */ |
| 772 | struct task_struct *j_task; |
| 773 | |
| 774 | /* |
| 775 | * Maximum number of metadata buffers to allow in a single compound |
| 776 | * commit transaction |
| 777 | */ |
| 778 | int j_max_transaction_buffers; |
| 779 | |
| 780 | /* |
| 781 | * What is the maximum transaction lifetime before we begin a commit? |
| 782 | */ |
| 783 | unsigned long j_commit_interval; |
| 784 | |
| 785 | /* The timer used to wakeup the commit thread: */ |
| 786 | struct timer_list *j_commit_timer; |
| 787 | |
| 788 | /* |
| 789 | * The revoke table: maintains the list of revoked blocks in the |
| 790 | * current transaction. [j_revoke_lock] |
| 791 | */ |
| 792 | spinlock_t j_revoke_lock; |
| 793 | struct jbd_revoke_table_s *j_revoke; |
| 794 | struct jbd_revoke_table_s *j_revoke_table[2]; |
| 795 | |
| 796 | /* |
| 797 | * array of bhs for journal_commit_transaction |
| 798 | */ |
| 799 | struct buffer_head **j_wbuf; |
| 800 | int j_wbufsize; |
| 801 | |
| 802 | /* |
| 803 | * An opaque pointer to fs-private information. ext3 puts its |
| 804 | * superblock pointer here |
| 805 | */ |
| 806 | void *j_private; |
| 807 | }; |
| 808 | |
| 809 | /* |
| 810 | * Journal flag definitions |
| 811 | */ |
| 812 | #define JFS_UNMOUNT 0x001 /* Journal thread is being destroyed */ |
| 813 | #define JFS_ABORT 0x002 /* Journaling has been aborted for errors. */ |
| 814 | #define JFS_ACK_ERR 0x004 /* The errno in the sb has been acked */ |
| 815 | #define JFS_FLUSHED 0x008 /* The journal superblock has been flushed */ |
| 816 | #define JFS_LOADED 0x010 /* The journal superblock has been loaded */ |
| 817 | #define JFS_BARRIER 0x020 /* Use IDE barriers */ |
| 818 | |
| 819 | /* |
| 820 | * Function declarations for the journaling transaction and buffer |
| 821 | * management |
| 822 | */ |
| 823 | |
| 824 | /* Filing buffers */ |
| 825 | extern void __journal_temp_unlink_buffer(struct journal_head *jh); |
| 826 | extern void journal_unfile_buffer(journal_t *, struct journal_head *); |
| 827 | extern void __journal_unfile_buffer(struct journal_head *); |
| 828 | extern void __journal_refile_buffer(struct journal_head *); |
| 829 | extern void journal_refile_buffer(journal_t *, struct journal_head *); |
| 830 | extern void __journal_file_buffer(struct journal_head *, transaction_t *, int); |
| 831 | extern void __journal_free_buffer(struct journal_head *bh); |
| 832 | extern void journal_file_buffer(struct journal_head *, transaction_t *, int); |
| 833 | extern void __journal_clean_data_list(transaction_t *transaction); |
| 834 | |
| 835 | /* Log buffer allocation */ |
| 836 | extern struct journal_head * journal_get_descriptor_buffer(journal_t *); |
| 837 | int journal_next_log_block(journal_t *, unsigned long *); |
| 838 | |
| 839 | /* Commit management */ |
| 840 | extern void journal_commit_transaction(journal_t *); |
| 841 | |
| 842 | /* Checkpoint list management */ |
| 843 | int __journal_clean_checkpoint_list(journal_t *journal); |
| 844 | void __journal_remove_checkpoint(struct journal_head *); |
| 845 | void __journal_insert_checkpoint(struct journal_head *, transaction_t *); |
| 846 | |
| 847 | /* Buffer IO */ |
| 848 | extern int |
| 849 | journal_write_metadata_buffer(transaction_t *transaction, |
| 850 | struct journal_head *jh_in, |
| 851 | struct journal_head **jh_out, |
| 852 | int blocknr); |
| 853 | |
| 854 | /* Transaction locking */ |
| 855 | extern void __wait_on_journal (journal_t *); |
| 856 | |
| 857 | /* |
| 858 | * Journal locking. |
| 859 | * |
| 860 | * We need to lock the journal during transaction state changes so that nobody |
| 861 | * ever tries to take a handle on the running transaction while we are in the |
| 862 | * middle of moving it to the commit phase. j_state_lock does this. |
| 863 | * |
| 864 | * Note that the locking is completely interrupt unsafe. We never touch |
| 865 | * journal structures from interrupts. |
| 866 | */ |
| 867 | |
| 868 | static inline handle_t *journal_current_handle(void) |
| 869 | { |
| 870 | return current->journal_info; |
| 871 | } |
| 872 | |
| 873 | /* The journaling code user interface: |
| 874 | * |
| 875 | * Create and destroy handles |
| 876 | * Register buffer modifications against the current transaction. |
| 877 | */ |
| 878 | |
| 879 | extern handle_t *journal_start(journal_t *, int nblocks); |
| 880 | extern int journal_restart (handle_t *, int nblocks); |
| 881 | extern int journal_extend (handle_t *, int nblocks); |
| 882 | extern int journal_get_write_access(handle_t *, struct buffer_head *); |
| 883 | extern int journal_get_create_access (handle_t *, struct buffer_head *); |
| 884 | extern int journal_get_undo_access(handle_t *, struct buffer_head *); |
| 885 | extern int journal_dirty_data (handle_t *, struct buffer_head *); |
| 886 | extern int journal_dirty_metadata (handle_t *, struct buffer_head *); |
| 887 | extern void journal_release_buffer (handle_t *, struct buffer_head *); |
| 888 | extern int journal_forget (handle_t *, struct buffer_head *); |
| 889 | extern void journal_sync_buffer (struct buffer_head *); |
| 890 | extern int journal_invalidatepage(journal_t *, |
| 891 | struct page *, unsigned long); |
| 892 | extern int journal_try_to_free_buffers(journal_t *, struct page *, int); |
| 893 | extern int journal_stop(handle_t *); |
| 894 | extern int journal_flush (journal_t *); |
| 895 | extern void journal_lock_updates (journal_t *); |
| 896 | extern void journal_unlock_updates (journal_t *); |
| 897 | |
| 898 | extern journal_t * journal_init_dev(struct block_device *bdev, |
| 899 | struct block_device *fs_dev, |
| 900 | int start, int len, int bsize); |
| 901 | extern journal_t * journal_init_inode (struct inode *); |
| 902 | extern int journal_update_format (journal_t *); |
| 903 | extern int journal_check_used_features |
| 904 | (journal_t *, unsigned long, unsigned long, unsigned long); |
| 905 | extern int journal_check_available_features |
| 906 | (journal_t *, unsigned long, unsigned long, unsigned long); |
| 907 | extern int journal_set_features |
| 908 | (journal_t *, unsigned long, unsigned long, unsigned long); |
| 909 | extern int journal_create (journal_t *); |
| 910 | extern int journal_load (journal_t *journal); |
| 911 | extern void journal_destroy (journal_t *); |
| 912 | extern int journal_recover (journal_t *journal); |
| 913 | extern int journal_wipe (journal_t *, int); |
| 914 | extern int journal_skip_recovery (journal_t *); |
| 915 | extern void journal_update_superblock (journal_t *, int); |
| 916 | extern void __journal_abort_hard (journal_t *); |
| 917 | extern void __journal_abort_soft (journal_t *, int); |
| 918 | extern void journal_abort (journal_t *, int); |
| 919 | extern int journal_errno (journal_t *); |
| 920 | extern void journal_ack_err (journal_t *); |
| 921 | extern int journal_clear_err (journal_t *); |
| 922 | extern int journal_bmap(journal_t *, unsigned long, unsigned long *); |
| 923 | extern int journal_force_commit(journal_t *); |
| 924 | |
| 925 | /* |
| 926 | * journal_head management |
| 927 | */ |
| 928 | struct journal_head *journal_add_journal_head(struct buffer_head *bh); |
| 929 | struct journal_head *journal_grab_journal_head(struct buffer_head *bh); |
| 930 | void journal_remove_journal_head(struct buffer_head *bh); |
| 931 | void journal_put_journal_head(struct journal_head *jh); |
| 932 | |
| 933 | /* |
| 934 | * handle management |
| 935 | */ |
| 936 | extern kmem_cache_t *jbd_handle_cache; |
| 937 | |
| 938 | static inline handle_t *jbd_alloc_handle(unsigned int __nocast gfp_flags) |
| 939 | { |
| 940 | return kmem_cache_alloc(jbd_handle_cache, gfp_flags); |
| 941 | } |
| 942 | |
| 943 | static inline void jbd_free_handle(handle_t *handle) |
| 944 | { |
| 945 | kmem_cache_free(jbd_handle_cache, handle); |
| 946 | } |
| 947 | |
| 948 | /* Primary revoke support */ |
| 949 | #define JOURNAL_REVOKE_DEFAULT_HASH 256 |
| 950 | extern int journal_init_revoke(journal_t *, int); |
| 951 | extern void journal_destroy_revoke_caches(void); |
| 952 | extern int journal_init_revoke_caches(void); |
| 953 | |
| 954 | extern void journal_destroy_revoke(journal_t *); |
| 955 | extern int journal_revoke (handle_t *, |
| 956 | unsigned long, struct buffer_head *); |
| 957 | extern int journal_cancel_revoke(handle_t *, struct journal_head *); |
| 958 | extern void journal_write_revoke_records(journal_t *, transaction_t *); |
| 959 | |
| 960 | /* Recovery revoke support */ |
| 961 | extern int journal_set_revoke(journal_t *, unsigned long, tid_t); |
| 962 | extern int journal_test_revoke(journal_t *, unsigned long, tid_t); |
| 963 | extern void journal_clear_revoke(journal_t *); |
| 964 | extern void journal_brelse_array(struct buffer_head *b[], int n); |
| 965 | extern void journal_switch_revoke_table(journal_t *journal); |
| 966 | |
| 967 | /* |
| 968 | * The log thread user interface: |
| 969 | * |
| 970 | * Request space in the current transaction, and force transaction commit |
| 971 | * transitions on demand. |
| 972 | */ |
| 973 | |
| 974 | int __log_space_left(journal_t *); /* Called with journal locked */ |
| 975 | int log_start_commit(journal_t *journal, tid_t tid); |
| 976 | int __log_start_commit(journal_t *journal, tid_t tid); |
| 977 | int journal_start_commit(journal_t *journal, tid_t *tid); |
| 978 | int journal_force_commit_nested(journal_t *journal); |
| 979 | int log_wait_commit(journal_t *journal, tid_t tid); |
| 980 | int log_do_checkpoint(journal_t *journal); |
| 981 | |
| 982 | void __log_wait_for_space(journal_t *journal); |
| 983 | extern void __journal_drop_transaction(journal_t *, transaction_t *); |
| 984 | extern int cleanup_journal_tail(journal_t *); |
| 985 | |
| 986 | /* Debugging code only: */ |
| 987 | |
| 988 | #define jbd_ENOSYS() \ |
| 989 | do { \ |
| 990 | printk (KERN_ERR "JBD unimplemented function %s\n", __FUNCTION__); \ |
| 991 | current->state = TASK_UNINTERRUPTIBLE; \ |
| 992 | schedule(); \ |
| 993 | } while (1) |
| 994 | |
| 995 | /* |
| 996 | * is_journal_abort |
| 997 | * |
| 998 | * Simple test wrapper function to test the JFS_ABORT state flag. This |
| 999 | * bit, when set, indicates that we have had a fatal error somewhere, |
| 1000 | * either inside the journaling layer or indicated to us by the client |
| 1001 | * (eg. ext3), and that we and should not commit any further |
| 1002 | * transactions. |
| 1003 | */ |
| 1004 | |
| 1005 | static inline int is_journal_aborted(journal_t *journal) |
| 1006 | { |
| 1007 | return journal->j_flags & JFS_ABORT; |
| 1008 | } |
| 1009 | |
| 1010 | static inline int is_handle_aborted(handle_t *handle) |
| 1011 | { |
| 1012 | if (handle->h_aborted) |
| 1013 | return 1; |
| 1014 | return is_journal_aborted(handle->h_transaction->t_journal); |
| 1015 | } |
| 1016 | |
| 1017 | static inline void journal_abort_handle(handle_t *handle) |
| 1018 | { |
| 1019 | handle->h_aborted = 1; |
| 1020 | } |
| 1021 | |
| 1022 | #endif /* __KERNEL__ */ |
| 1023 | |
| 1024 | /* Comparison functions for transaction IDs: perform comparisons using |
| 1025 | * modulo arithmetic so that they work over sequence number wraps. */ |
| 1026 | |
| 1027 | static inline int tid_gt(tid_t x, tid_t y) |
| 1028 | { |
| 1029 | int difference = (x - y); |
| 1030 | return (difference > 0); |
| 1031 | } |
| 1032 | |
| 1033 | static inline int tid_geq(tid_t x, tid_t y) |
| 1034 | { |
| 1035 | int difference = (x - y); |
| 1036 | return (difference >= 0); |
| 1037 | } |
| 1038 | |
| 1039 | extern int journal_blocks_per_page(struct inode *inode); |
| 1040 | |
| 1041 | /* |
| 1042 | * Return the minimum number of blocks which must be free in the journal |
| 1043 | * before a new transaction may be started. Must be called under j_state_lock. |
| 1044 | */ |
| 1045 | static inline int jbd_space_needed(journal_t *journal) |
| 1046 | { |
| 1047 | int nblocks = journal->j_max_transaction_buffers; |
| 1048 | if (journal->j_committing_transaction) |
| 1049 | nblocks += journal->j_committing_transaction-> |
| 1050 | t_outstanding_credits; |
| 1051 | return nblocks; |
| 1052 | } |
| 1053 | |
| 1054 | /* |
| 1055 | * Definitions which augment the buffer_head layer |
| 1056 | */ |
| 1057 | |
| 1058 | /* journaling buffer types */ |
| 1059 | #define BJ_None 0 /* Not journaled */ |
| 1060 | #define BJ_SyncData 1 /* Normal data: flush before commit */ |
| 1061 | #define BJ_Metadata 2 /* Normal journaled metadata */ |
| 1062 | #define BJ_Forget 3 /* Buffer superseded by this transaction */ |
| 1063 | #define BJ_IO 4 /* Buffer is for temporary IO use */ |
| 1064 | #define BJ_Shadow 5 /* Buffer contents being shadowed to the log */ |
| 1065 | #define BJ_LogCtl 6 /* Buffer contains log descriptors */ |
| 1066 | #define BJ_Reserved 7 /* Buffer is reserved for access by journal */ |
| 1067 | #define BJ_Locked 8 /* Locked for I/O during commit */ |
| 1068 | #define BJ_Types 9 |
| 1069 | |
| 1070 | extern int jbd_blocks_per_page(struct inode *inode); |
| 1071 | |
| 1072 | #ifdef __KERNEL__ |
| 1073 | |
| 1074 | #define buffer_trace_init(bh) do {} while (0) |
| 1075 | #define print_buffer_fields(bh) do {} while (0) |
| 1076 | #define print_buffer_trace(bh) do {} while (0) |
| 1077 | #define BUFFER_TRACE(bh, info) do {} while (0) |
| 1078 | #define BUFFER_TRACE2(bh, bh2, info) do {} while (0) |
| 1079 | #define JBUFFER_TRACE(jh, info) do {} while (0) |
| 1080 | |
| 1081 | #endif /* __KERNEL__ */ |
| 1082 | |
| 1083 | #endif /* CONFIG_JBD || CONFIG_JBD_MODULE || !__KERNEL__ */ |
| 1084 | |
| 1085 | /* |
| 1086 | * Compatibility no-ops which allow the kernel to compile without CONFIG_JBD |
| 1087 | * go here. |
| 1088 | */ |
| 1089 | |
| 1090 | #if defined(__KERNEL__) && !(defined(CONFIG_JBD) || defined(CONFIG_JBD_MODULE)) |
| 1091 | |
| 1092 | #define J_ASSERT(expr) do {} while (0) |
| 1093 | #define J_ASSERT_BH(bh, expr) do {} while (0) |
| 1094 | #define buffer_jbd(bh) 0 |
| 1095 | #define journal_buffer_journal_lru(bh) 0 |
| 1096 | |
| 1097 | #endif /* defined(__KERNEL__) && !defined(CONFIG_JBD) */ |
| 1098 | #endif /* _LINUX_JBD_H */ |