1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * linux/include/linux/jbd2.h
5 * Written by Stephen C. Tweedie <sct@redhat.com>
7 * Copyright 1998-2000 Red Hat, Inc --- All Rights Reserved
9 * Definitions for transaction data structures for the buffer cache
10 * filesystem journaling support.
16 /* Allow this file to be included directly into e2fsprogs */
18 #include "jfs_compat.h"
22 #include <linux/types.h>
23 #include <linux/buffer_head.h>
24 #include <linux/journal-head.h>
25 #include <linux/stddef.h>
26 #include <linux/mutex.h>
27 #include <linux/timer.h>
28 #include <linux/slab.h>
29 #include <linux/bit_spinlock.h>
30 #include <crypto/hash.h>
33 #define journal_oom_retry 1
36 * Define JBD2_PARANIOD_IOFAIL to cause a kernel BUG() if ext4 finds
37 * certain classes of error which can occur due to failed IOs. Under
38 * normal use we want ext4 to continue after such errors, because
39 * hardware _can_ fail, but for debugging purposes when running tests on
40 * known-good hardware we may want to trap these errors.
42 #undef JBD2_PARANOID_IOFAIL
45 * The default maximum commit age, in seconds.
47 #define JBD2_DEFAULT_MAX_COMMIT_AGE 5
49 #ifdef CONFIG_JBD2_DEBUG
51 * Define JBD2_EXPENSIVE_CHECKING to enable more expensive internal
52 * consistency checks. By default we don't do this unless
53 * CONFIG_JBD2_DEBUG is on.
55 #define JBD2_EXPENSIVE_CHECKING
56 extern ushort jbd2_journal_enable_debug;
57 void __jbd2_debug(int level, const char *file, const char *func,
58 unsigned int line, const char *fmt, ...);
60 #define jbd_debug(n, fmt, a...) \
61 __jbd2_debug((n), __FILE__, __func__, __LINE__, (fmt), ##a)
63 #define jbd_debug(n, fmt, a...) /**/
66 extern void *jbd2_alloc(size_t size, gfp_t flags);
67 extern void jbd2_free(void *ptr, size_t size);
69 #define JBD2_MIN_JOURNAL_BLOCKS 1024
74 * typedef handle_t - The handle_t type represents a single atomic update being performed by some process.
76 * All filesystem modifications made by the process go
77 * through this handle. Recursive operations (such as quota operations)
78 * are gathered into a single update.
80 * The buffer credits field is used to account for journaled buffers
81 * being modified by the running process. To ensure that there is
82 * enough log space for all outstanding operations, we need to limit the
83 * number of outstanding buffers possible at any time. When the
84 * operation completes, any buffer credits not used are credited back to
85 * the transaction, so that at all times we know how many buffers the
86 * outstanding updates on a transaction might possibly touch.
88 * This is an opaque datatype.
90 typedef struct jbd2_journal_handle handle_t; /* Atomic operation type */
94 * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem.
96 * journal_t is linked to from the fs superblock structure.
98 * We use the journal_t to keep track of all outstanding transaction
99 * activity on the filesystem, and to manage the state of the log
102 * This is an opaque datatype.
104 typedef struct journal_s journal_t; /* Journal control structure */
108 * Internal structures used by the logging mechanism:
111 #define JBD2_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */
118 * Descriptor block types:
121 #define JBD2_DESCRIPTOR_BLOCK 1
122 #define JBD2_COMMIT_BLOCK 2
123 #define JBD2_SUPERBLOCK_V1 3
124 #define JBD2_SUPERBLOCK_V2 4
125 #define JBD2_REVOKE_BLOCK 5
128 * Standard header for all descriptor blocks:
130 typedef struct journal_header_s
140 #define JBD2_CRC32_CHKSUM 1
141 #define JBD2_MD5_CHKSUM 2
142 #define JBD2_SHA1_CHKSUM 3
143 #define JBD2_CRC32C_CHKSUM 4
145 #define JBD2_CRC32_CHKSUM_SIZE 4
147 #define JBD2_CHECKSUM_BYTES (32 / sizeof(u32))
149 * Commit block header for storing transactional checksums:
151 * NOTE: If FEATURE_COMPAT_CHECKSUM (checksum v1) is set, the h_chksum*
152 * fields are used to store a checksum of the descriptor and data blocks.
154 * If FEATURE_INCOMPAT_CSUM_V2 (checksum v2) is set, then the h_chksum
155 * field is used to store crc32c(uuid+commit_block). Each journal metadata
156 * block gets its own checksum, and data block checksums are stored in
157 * journal_block_tag (in the descriptor). The other h_chksum* fields are
160 * If FEATURE_INCOMPAT_CSUM_V3 is set, the descriptor block uses
161 * journal_block_tag3_t to store a full 32-bit checksum. Everything else
164 * Checksum v1, v2, and v3 are mutually exclusive features.
166 struct commit_header {
170 unsigned char h_chksum_type;
171 unsigned char h_chksum_size;
172 unsigned char h_padding[2];
173 __be32 h_chksum[JBD2_CHECKSUM_BYTES];
175 __be32 h_commit_nsec;
179 * The block tag: used to describe a single buffer in the journal.
180 * t_blocknr_high is only used if INCOMPAT_64BIT is set, so this
181 * raw struct shouldn't be used for pointer math or sizeof() - use
182 * journal_tag_bytes(journal) instead to compute this.
184 typedef struct journal_block_tag3_s
186 __be32 t_blocknr; /* The on-disk block number */
187 __be32 t_flags; /* See below */
188 __be32 t_blocknr_high; /* most-significant high 32bits. */
189 __be32 t_checksum; /* crc32c(uuid+seq+block) */
190 } journal_block_tag3_t;
192 typedef struct journal_block_tag_s
194 __be32 t_blocknr; /* The on-disk block number */
195 __be16 t_checksum; /* truncated crc32c(uuid+seq+block) */
196 __be16 t_flags; /* See below */
197 __be32 t_blocknr_high; /* most-significant high 32bits. */
198 } journal_block_tag_t;
200 /* Tail of descriptor or revoke block, for checksumming */
201 struct jbd2_journal_block_tail {
202 __be32 t_checksum; /* crc32c(uuid+descr_block) */
206 * The revoke descriptor: used on disk to describe a series of blocks to
207 * be revoked from the log
209 typedef struct jbd2_journal_revoke_header_s
211 journal_header_t r_header;
212 __be32 r_count; /* Count of bytes used in the block */
213 } jbd2_journal_revoke_header_t;
215 /* Definitions for the journal tag flags word: */
216 #define JBD2_FLAG_ESCAPE 1 /* on-disk block is escaped */
217 #define JBD2_FLAG_SAME_UUID 2 /* block has same uuid as previous */
218 #define JBD2_FLAG_DELETED 4 /* block deleted by this transaction */
219 #define JBD2_FLAG_LAST_TAG 8 /* last tag in this descriptor block */
223 * The journal superblock. All fields are in big-endian byte order.
225 typedef struct journal_superblock_s
228 journal_header_t s_header;
231 /* Static information describing the journal */
232 __be32 s_blocksize; /* journal device blocksize */
233 __be32 s_maxlen; /* total blocks in journal file */
234 __be32 s_first; /* first block of log information */
237 /* Dynamic information describing the current state of the log */
238 __be32 s_sequence; /* first commit ID expected in log */
239 __be32 s_start; /* blocknr of start of log */
242 /* Error value, as set by jbd2_journal_abort(). */
246 /* Remaining fields are only valid in a version-2 superblock */
247 __be32 s_feature_compat; /* compatible feature set */
248 __be32 s_feature_incompat; /* incompatible feature set */
249 __be32 s_feature_ro_compat; /* readonly-compatible feature set */
251 __u8 s_uuid[16]; /* 128-bit uuid for journal */
254 __be32 s_nr_users; /* Nr of filesystems sharing log */
256 __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/
259 __be32 s_max_transaction; /* Limit of journal blocks per trans.*/
260 __be32 s_max_trans_data; /* Limit of data blocks per trans. */
263 __u8 s_checksum_type; /* checksum type */
266 __be32 s_checksum; /* crc32c(superblock) */
269 __u8 s_users[16*48]; /* ids of all fs'es sharing the log */
271 } journal_superblock_t;
273 /* Use the jbd2_{has,set,clear}_feature_* helpers; these will be removed */
274 #define JBD2_HAS_COMPAT_FEATURE(j,mask) \
275 ((j)->j_format_version >= 2 && \
276 ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask))))
277 #define JBD2_HAS_RO_COMPAT_FEATURE(j,mask) \
278 ((j)->j_format_version >= 2 && \
279 ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask))))
280 #define JBD2_HAS_INCOMPAT_FEATURE(j,mask) \
281 ((j)->j_format_version >= 2 && \
282 ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask))))
284 #define JBD2_FEATURE_COMPAT_CHECKSUM 0x00000001
286 #define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001
287 #define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002
288 #define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT 0x00000004
289 #define JBD2_FEATURE_INCOMPAT_CSUM_V2 0x00000008
290 #define JBD2_FEATURE_INCOMPAT_CSUM_V3 0x00000010
292 /* See "journal feature predicate functions" below */
294 /* Features known to this kernel version: */
295 #define JBD2_KNOWN_COMPAT_FEATURES JBD2_FEATURE_COMPAT_CHECKSUM
296 #define JBD2_KNOWN_ROCOMPAT_FEATURES 0
297 #define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \
298 JBD2_FEATURE_INCOMPAT_64BIT | \
299 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | \
300 JBD2_FEATURE_INCOMPAT_CSUM_V2 | \
301 JBD2_FEATURE_INCOMPAT_CSUM_V3)
305 #include <linux/fs.h>
306 #include <linux/sched.h>
308 enum jbd_state_bits {
309 BH_JBD /* Has an attached ext3 journal_head */
311 BH_JWrite, /* Being written to log (@@@ DEBUGGING) */
312 BH_Freed, /* Has been freed (truncated) */
313 BH_Revoked, /* Has been revoked from the log */
314 BH_RevokeValid, /* Revoked flag is valid */
315 BH_JBDDirty, /* Is dirty but journaled */
316 BH_State, /* Pins most journal_head state */
317 BH_JournalHead, /* Pins bh->b_private and jh->b_bh */
318 BH_Shadow, /* IO on shadow buffer is running */
319 BH_Verified, /* Metadata block has been verified ok */
320 BH_JBDPrivateStart, /* First bit available for private use by FS */
324 BUFFER_FNS(JWrite, jwrite)
325 BUFFER_FNS(JBDDirty, jbddirty)
326 TAS_BUFFER_FNS(JBDDirty, jbddirty)
327 BUFFER_FNS(Revoked, revoked)
328 TAS_BUFFER_FNS(Revoked, revoked)
329 BUFFER_FNS(RevokeValid, revokevalid)
330 TAS_BUFFER_FNS(RevokeValid, revokevalid)
331 BUFFER_FNS(Freed, freed)
332 BUFFER_FNS(Shadow, shadow)
333 BUFFER_FNS(Verified, verified)
335 static inline struct buffer_head *jh2bh(struct journal_head *jh)
340 static inline struct journal_head *bh2jh(struct buffer_head *bh)
342 return bh->b_private;
345 static inline void jbd_lock_bh_state(struct buffer_head *bh)
347 bit_spin_lock(BH_State, &bh->b_state);
350 static inline int jbd_trylock_bh_state(struct buffer_head *bh)
352 return bit_spin_trylock(BH_State, &bh->b_state);
355 static inline int jbd_is_locked_bh_state(struct buffer_head *bh)
357 return bit_spin_is_locked(BH_State, &bh->b_state);
360 static inline void jbd_unlock_bh_state(struct buffer_head *bh)
362 bit_spin_unlock(BH_State, &bh->b_state);
365 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh)
367 bit_spin_lock(BH_JournalHead, &bh->b_state);
370 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
372 bit_spin_unlock(BH_JournalHead, &bh->b_state);
375 #define J_ASSERT(assert) BUG_ON(!(assert))
377 #define J_ASSERT_BH(bh, expr) J_ASSERT(expr)
378 #define J_ASSERT_JH(jh, expr) J_ASSERT(expr)
380 #if defined(JBD2_PARANOID_IOFAIL)
381 #define J_EXPECT(expr, why...) J_ASSERT(expr)
382 #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr)
383 #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr)
385 #define __journal_expect(expr, why...) \
390 "JBD2 unexpected failure: %s: %s;\n", \
392 printk(KERN_ERR why "\n"); \
396 #define J_EXPECT(expr, why...) __journal_expect(expr, ## why)
397 #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why)
398 #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why)
401 /* Flags in jbd_inode->i_flags */
402 #define __JI_COMMIT_RUNNING 0
403 #define __JI_WRITE_DATA 1
404 #define __JI_WAIT_DATA 2
407 * Commit of the inode data in progress. We use this flag to protect us from
408 * concurrent deletion of inode. We cannot use reference to inode for this
409 * since we cannot afford doing last iput() on behalf of kjournald
411 #define JI_COMMIT_RUNNING (1 << __JI_COMMIT_RUNNING)
412 /* Write allocated dirty buffers in this inode before commit */
413 #define JI_WRITE_DATA (1 << __JI_WRITE_DATA)
414 /* Wait for outstanding data writes for this inode before commit */
415 #define JI_WAIT_DATA (1 << __JI_WAIT_DATA)
418 * struct jbd_inode - The jbd_inode type is the structure linking inodes in
419 * ordered mode present in a transaction so that we can sync them during commit.
425 * Which transaction does this inode belong to? Either the running
426 * transaction or the committing one. [j_list_lock]
428 transaction_t *i_transaction;
431 * @i_next_transaction:
433 * Pointer to the running transaction modifying inode's data in case
434 * there is already a committing transaction touching it. [j_list_lock]
436 transaction_t *i_next_transaction;
439 * @i_list: List of inodes in the i_transaction [j_list_lock]
441 struct list_head i_list;
446 * VFS inode this inode belongs to [constant for lifetime of structure]
448 struct inode *i_vfs_inode;
451 * @i_flags: Flags of inode [j_list_lock]
453 unsigned long i_flags;
456 struct jbd2_revoke_table_s;
459 * struct handle_s - The handle_s type is the concrete type associated with
461 * @h_transaction: Which compound transaction is this update a part of?
462 * @h_journal: Which journal handle belongs to - used iff h_reserved set.
463 * @h_rsv_handle: Handle reserved for finishing the logical operation.
464 * @h_buffer_credits: Number of remaining buffers we are allowed to dirty.
465 * @h_ref: Reference count on this handle.
466 * @h_err: Field for caller's use to track errors through large fs operations.
467 * @h_sync: Flag for sync-on-close.
468 * @h_jdata: Flag to force data journaling.
469 * @h_reserved: Flag for handle for reserved credits.
470 * @h_aborted: Flag indicating fatal error on handle.
471 * @h_type: For handle statistics.
472 * @h_line_no: For handle statistics.
473 * @h_start_jiffies: Handle Start time.
474 * @h_requested_credits: Holds @h_buffer_credits after handle is started.
475 * @saved_alloc_context: Saved context while transaction is open.
478 /* Docbook can't yet cope with the bit fields, but will leave the documentation
479 * in so it can be fixed later.
482 struct jbd2_journal_handle
485 transaction_t *h_transaction;
486 /* Which journal handle belongs to - used iff h_reserved set */
487 journal_t *h_journal;
490 handle_t *h_rsv_handle;
491 int h_buffer_credits;
495 /* Flags [no locking] */
496 unsigned int h_sync: 1;
497 unsigned int h_jdata: 1;
498 unsigned int h_reserved: 1;
499 unsigned int h_aborted: 1;
500 unsigned int h_type: 8;
501 unsigned int h_line_no: 16;
503 unsigned long h_start_jiffies;
504 unsigned int h_requested_credits;
506 unsigned int saved_alloc_context;
511 * Some stats for checkpoint phase
513 struct transaction_chp_stats_s {
514 unsigned long cs_chp_time;
515 __u32 cs_forced_to_close;
520 /* The transaction_t type is the guts of the journaling mechanism. It
521 * tracks a compound transaction through its various states:
523 * RUNNING: accepting new updates
524 * LOCKED: Updates still running but we don't accept new ones
525 * RUNDOWN: Updates are tidying up but have finished requesting
526 * new buffers to modify (state not used for now)
527 * FLUSH: All updates complete, but we are still writing to disk
528 * COMMIT: All data on disk, writing commit record
529 * FINISHED: We still have to keep the transaction for checkpointing.
531 * The transaction keeps track of all of the buffers modified by a
532 * running transaction, and all of the buffers committed but not yet
533 * flushed to home for finished transactions.
540 * ->jbd_lock_bh_journal_head() (This is "innermost")
543 * ->jbd_lock_bh_state()
545 * jbd_lock_bh_state()
552 * ->j_list_lock (journal_unmap_buffer)
558 /* Pointer to the journal for this transaction. [no locking] */
559 journal_t *t_journal;
561 /* Sequence number for this transaction [no locking] */
565 * Transaction's current state
566 * [no locking - only kjournald2 alters this]
567 * [j_list_lock] guards transition of a transaction into T_FINISHED
568 * state and subsequent call of __jbd2_journal_drop_transaction()
569 * FIXME: needs barriers
570 * KLUDGE: [use j_state_lock]
585 * Where in the log does this transaction's commit start? [no locking]
587 unsigned long t_log_start;
589 /* Number of buffers on the t_buffers list [j_list_lock] */
593 * Doubly-linked circular list of all buffers reserved but not yet
594 * modified by this transaction [j_list_lock]
596 struct journal_head *t_reserved_list;
599 * Doubly-linked circular list of all metadata buffers owned by this
600 * transaction [j_list_lock]
602 struct journal_head *t_buffers;
605 * Doubly-linked circular list of all forget buffers (superseded
606 * buffers which we can un-checkpoint once this transaction commits)
609 struct journal_head *t_forget;
612 * Doubly-linked circular list of all buffers still to be flushed before
613 * this transaction can be checkpointed. [j_list_lock]
615 struct journal_head *t_checkpoint_list;
618 * Doubly-linked circular list of all buffers submitted for IO while
619 * checkpointing. [j_list_lock]
621 struct journal_head *t_checkpoint_io_list;
624 * Doubly-linked circular list of metadata buffers being shadowed by log
625 * IO. The IO buffers on the iobuf list and the shadow buffers on this
626 * list match each other one for one at all times. [j_list_lock]
628 struct journal_head *t_shadow_list;
631 * List of inodes whose data we've modified in data=ordered mode.
634 struct list_head t_inode_list;
637 * Protects info related to handles
639 spinlock_t t_handle_lock;
642 * Longest time some handle had to wait for running transaction
644 unsigned long t_max_wait;
647 * When transaction started
649 unsigned long t_start;
652 * When commit was requested
654 unsigned long t_requested;
657 * Checkpointing stats [j_checkpoint_sem]
659 struct transaction_chp_stats_s t_chp_stats;
662 * Number of outstanding updates running on this transaction
668 * Number of buffers reserved for use by all handles in this transaction
669 * handle but not yet modified. [none]
671 atomic_t t_outstanding_credits;
674 * Forward and backward links for the circular list of all transactions
675 * awaiting checkpoint. [j_list_lock]
677 transaction_t *t_cpnext, *t_cpprev;
680 * When will the transaction expire (become due for commit), in jiffies?
683 unsigned long t_expires;
686 * When this transaction started, in nanoseconds [no locking]
688 ktime_t t_start_time;
691 * How many handles used this transaction? [none]
693 atomic_t t_handle_count;
696 * This transaction is being forced and some process is
697 * waiting for it to finish.
699 unsigned int t_synchronous_commit:1;
701 /* Disk flush needs to be sent to fs partition [no locking] */
702 int t_need_data_flush;
705 * For use by the filesystem to store fs-specific data
706 * structures associated with the transaction
708 struct list_head t_private_list;
711 struct transaction_run_stats_s {
712 unsigned long rs_wait;
713 unsigned long rs_request_delay;
714 unsigned long rs_running;
715 unsigned long rs_locked;
716 unsigned long rs_flushing;
717 unsigned long rs_logging;
719 __u32 rs_handle_count;
721 __u32 rs_blocks_logged;
724 struct transaction_stats_s {
725 unsigned long ts_tid;
726 unsigned long ts_requested;
727 struct transaction_run_stats_s run;
730 static inline unsigned long
731 jbd2_time_diff(unsigned long start, unsigned long end)
736 return end + (MAX_JIFFY_OFFSET - start);
739 #define JBD2_NR_BATCH 64
742 * struct journal_s - The journal_s type is the concrete type associated with
748 * @j_flags: General journaling state flags [j_state_lock]
750 unsigned long j_flags;
755 * Is there an outstanding uncleared error on the journal (from a prior
756 * abort)? [j_state_lock]
761 * @j_sb_buffer: The first part of the superblock buffer.
763 struct buffer_head *j_sb_buffer;
766 * @j_superblock: The second part of the superblock buffer.
768 journal_superblock_t *j_superblock;
771 * @j_format_version: Version of the superblock format.
773 int j_format_version;
776 * @j_state_lock: Protect the various scalars in the journal.
778 rwlock_t j_state_lock;
783 * Number of processes waiting to create a barrier lock [j_state_lock]
788 * @j_barrier: The barrier lock itself.
790 struct mutex j_barrier;
793 * @j_running_transaction:
795 * Transactions: The current running transaction...
796 * [j_state_lock] [caller holding open handle]
798 transaction_t *j_running_transaction;
801 * @j_committing_transaction:
803 * the transaction we are pushing to disk
804 * [j_state_lock] [caller holding open handle]
806 transaction_t *j_committing_transaction;
809 * @j_checkpoint_transactions:
811 * ... and a linked circular list of all transactions waiting for
812 * checkpointing. [j_list_lock]
814 transaction_t *j_checkpoint_transactions;
817 * @j_wait_transaction_locked:
819 * Wait queue for waiting for a locked transaction to start committing,
820 * or for a barrier lock to be released.
822 wait_queue_head_t j_wait_transaction_locked;
825 * @j_wait_done_commit: Wait queue for waiting for commit to complete.
827 wait_queue_head_t j_wait_done_commit;
830 * @j_wait_commit: Wait queue to trigger commit.
832 wait_queue_head_t j_wait_commit;
835 * @j_wait_updates: Wait queue to wait for updates to complete.
837 wait_queue_head_t j_wait_updates;
842 * Wait queue to wait for reserved buffer credits to drop.
844 wait_queue_head_t j_wait_reserved;
847 * @j_checkpoint_mutex:
849 * Semaphore for locking against concurrent checkpoints.
851 struct mutex j_checkpoint_mutex;
856 * List of buffer heads used by the checkpoint routine. This
857 * was moved from jbd2_log_do_checkpoint() to reduce stack
858 * usage. Access to this array is controlled by the
859 * @j_checkpoint_mutex. [j_checkpoint_mutex]
861 struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH];
866 * Journal head: identifies the first unused block in the journal.
869 unsigned long j_head;
874 * Journal tail: identifies the oldest still-used block in the journal.
877 unsigned long j_tail;
882 * Journal free: how many free blocks are there in the journal?
885 unsigned long j_free;
890 * The block number of the first usable block in the journal
893 unsigned long j_first;
898 * The block number one beyond the last usable block in the journal
901 unsigned long j_last;
904 * @j_dev: Device where we store the journal.
906 struct block_device *j_dev;
909 * @j_blocksize: Block size for the location where we store the journal.
916 * Starting block offset into the device where we store the journal.
918 unsigned long long j_blk_offset;
921 * @j_devname: Journal device name.
923 char j_devname[BDEVNAME_SIZE+24];
928 * Device which holds the client fs. For internal journal this will be
931 struct block_device *j_fs_dev;
934 * @j_maxlen: Total maximum capacity of the journal region on disk.
936 unsigned int j_maxlen;
939 * @j_reserved_credits:
941 * Number of buffers reserved from the running transaction.
943 atomic_t j_reserved_credits;
946 * @j_list_lock: Protects the buffer lists and internal buffer state.
948 spinlock_t j_list_lock;
953 * Optional inode where we store the journal. If present, all
954 * journal block numbers are mapped into this inode via bmap().
956 struct inode *j_inode;
961 * Sequence number of the oldest transaction in the log [j_state_lock]
963 tid_t j_tail_sequence;
966 * @j_transaction_sequence:
968 * Sequence number of the next transaction to grant [j_state_lock]
970 tid_t j_transaction_sequence;
973 * @j_commit_sequence:
975 * Sequence number of the most recently committed transaction
978 tid_t j_commit_sequence;
983 * Sequence number of the most recent transaction wanting commit
986 tid_t j_commit_request;
991 * Journal uuid: identifies the object (filesystem, LVM volume etc)
992 * backed by this journal. This will eventually be replaced by an array
993 * of uuids, allowing us to index multiple devices within a single
994 * journal and to perform atomic updates across them.
999 * @j_task: Pointer to the current commit thread for this journal.
1001 struct task_struct *j_task;
1004 * @j_max_transaction_buffers:
1006 * Maximum number of metadata buffers to allow in a single compound
1007 * commit transaction.
1009 int j_max_transaction_buffers;
1012 * @j_commit_interval:
1014 * What is the maximum transaction lifetime before we begin a commit?
1016 unsigned long j_commit_interval;
1019 * @j_commit_timer: The timer used to wakeup the commit thread.
1021 struct timer_list j_commit_timer;
1024 * @j_revoke_lock: Protect the revoke table.
1026 spinlock_t j_revoke_lock;
1031 * The revoke table - maintains the list of revoked blocks in the
1032 * current transaction.
1034 struct jbd2_revoke_table_s *j_revoke;
1037 * @j_revoke_table: Alternate revoke tables for j_revoke.
1039 struct jbd2_revoke_table_s *j_revoke_table[2];
1042 * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction.
1044 struct buffer_head **j_wbuf;
1049 * Size of @j_wbuf array.
1054 * @j_last_sync_writer:
1056 * The pid of the last person to run a synchronous operation
1057 * through the journal.
1059 pid_t j_last_sync_writer;
1062 * @j_average_commit_time:
1064 * The average amount of time in nanoseconds it takes to commit a
1065 * transaction to disk. [j_state_lock]
1067 u64 j_average_commit_time;
1070 * @j_min_batch_time:
1072 * Minimum time that we should wait for additional filesystem operations
1073 * to get batched into a synchronous handle in microseconds.
1075 u32 j_min_batch_time;
1078 * @j_max_batch_time:
1080 * Maximum time that we should wait for additional filesystem operations
1081 * to get batched into a synchronous handle in microseconds.
1083 u32 j_max_batch_time;
1086 * @j_commit_callback:
1088 * This function is called when a transaction is closed.
1090 void (*j_commit_callback)(journal_t *,
1094 * Journal statistics
1098 * @j_history_lock: Protect the transactions statistics history.
1100 spinlock_t j_history_lock;
1103 * @j_proc_entry: procfs entry for the jbd statistics directory.
1105 struct proc_dir_entry *j_proc_entry;
1108 * @j_stats: Overall statistics.
1110 struct transaction_stats_s j_stats;
1113 * @j_failed_commit: Failed journal commit ID.
1115 unsigned int j_failed_commit;
1120 * An opaque pointer to fs-private information. ext3 puts its
1121 * superblock pointer here.
1128 * Reference to checksum algorithm driver via cryptoapi.
1130 struct crypto_shash *j_chksum_driver;
1135 * Precomputed journal UUID checksum for seeding other checksums.
1139 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1141 * @j_trans_commit_map:
1143 * Lockdep entity to track transaction commit dependencies. Handles
1144 * hold this "lock" for read, when we wait for commit, we acquire the
1145 * "lock" for writing. This matches the properties of jbd2 journalling
1146 * where the running transaction has to wait for all handles to be
1147 * dropped to commit that transaction and also acquiring a handle may
1148 * require transaction commit to finish.
1150 struct lockdep_map j_trans_commit_map;
1154 #define jbd2_might_wait_for_commit(j) \
1156 rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \
1157 rwsem_release(&j->j_trans_commit_map, 1, _THIS_IP_); \
1160 /* journal feature predicate functions */
1161 #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \
1162 static inline bool jbd2_has_feature_##name(journal_t *j) \
1164 return ((j)->j_format_version >= 2 && \
1165 ((j)->j_superblock->s_feature_compat & \
1166 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \
1168 static inline void jbd2_set_feature_##name(journal_t *j) \
1170 (j)->j_superblock->s_feature_compat |= \
1171 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \
1173 static inline void jbd2_clear_feature_##name(journal_t *j) \
1175 (j)->j_superblock->s_feature_compat &= \
1176 ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \
1179 #define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1180 static inline bool jbd2_has_feature_##name(journal_t *j) \
1182 return ((j)->j_format_version >= 2 && \
1183 ((j)->j_superblock->s_feature_ro_compat & \
1184 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \
1186 static inline void jbd2_set_feature_##name(journal_t *j) \
1188 (j)->j_superblock->s_feature_ro_compat |= \
1189 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \
1191 static inline void jbd2_clear_feature_##name(journal_t *j) \
1193 (j)->j_superblock->s_feature_ro_compat &= \
1194 ~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \
1197 #define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1198 static inline bool jbd2_has_feature_##name(journal_t *j) \
1200 return ((j)->j_format_version >= 2 && \
1201 ((j)->j_superblock->s_feature_incompat & \
1202 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \
1204 static inline void jbd2_set_feature_##name(journal_t *j) \
1206 (j)->j_superblock->s_feature_incompat |= \
1207 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \
1209 static inline void jbd2_clear_feature_##name(journal_t *j) \
1211 (j)->j_superblock->s_feature_incompat &= \
1212 ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \
1215 JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM)
1217 JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE)
1218 JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT)
1219 JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT)
1220 JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2)
1221 JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3)
1224 * Journal flag definitions
1226 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */
1227 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */
1228 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */
1229 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */
1230 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */
1231 #define JBD2_BARRIER 0x020 /* Use IDE barriers */
1232 #define JBD2_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file
1233 * data write error in ordered
1235 #define JBD2_REC_ERR 0x080 /* The errno in the sb has been recorded */
1238 * Function declarations for the journaling transaction and buffer
1242 /* Filing buffers */
1243 extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *);
1244 extern void __jbd2_journal_refile_buffer(struct journal_head *);
1245 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *);
1246 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
1247 extern void __journal_free_buffer(struct journal_head *bh);
1248 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
1249 extern void __journal_clean_data_list(transaction_t *transaction);
1250 static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh)
1252 list_add_tail(&bh->b_assoc_buffers, head);
1254 static inline void jbd2_unfile_log_bh(struct buffer_head *bh)
1256 list_del_init(&bh->b_assoc_buffers);
1259 /* Log buffer allocation */
1260 struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int);
1261 void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *);
1262 int jbd2_journal_next_log_block(journal_t *, unsigned long long *);
1263 int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid,
1264 unsigned long *block);
1265 int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block);
1266 void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block);
1268 /* Commit management */
1269 extern void jbd2_journal_commit_transaction(journal_t *);
1271 /* Checkpoint list management */
1272 void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy);
1273 int __jbd2_journal_remove_checkpoint(struct journal_head *);
1274 void jbd2_journal_destroy_checkpoint(journal_t *journal);
1275 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *);
1282 struct jbd2_buffer_trigger_type {
1284 * Fired a the moment data to write to the journal are known to be
1285 * stable - so either at the moment b_frozen_data is created or just
1286 * before a buffer is written to the journal. mapped_data is a mapped
1287 * buffer that is the frozen data for commit.
1289 void (*t_frozen)(struct jbd2_buffer_trigger_type *type,
1290 struct buffer_head *bh, void *mapped_data,
1294 * Fired during journal abort for dirty buffers that will not be
1297 void (*t_abort)(struct jbd2_buffer_trigger_type *type,
1298 struct buffer_head *bh);
1301 extern void jbd2_buffer_frozen_trigger(struct journal_head *jh,
1303 struct jbd2_buffer_trigger_type *triggers);
1304 extern void jbd2_buffer_abort_trigger(struct journal_head *jh,
1305 struct jbd2_buffer_trigger_type *triggers);
1308 extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
1309 struct journal_head *jh_in,
1310 struct buffer_head **bh_out,
1313 /* Transaction locking */
1314 extern void __wait_on_journal (journal_t *);
1316 /* Transaction cache support */
1317 extern void jbd2_journal_destroy_transaction_cache(void);
1318 extern int __init jbd2_journal_init_transaction_cache(void);
1319 extern void jbd2_journal_free_transaction(transaction_t *);
1324 * We need to lock the journal during transaction state changes so that nobody
1325 * ever tries to take a handle on the running transaction while we are in the
1326 * middle of moving it to the commit phase. j_state_lock does this.
1328 * Note that the locking is completely interrupt unsafe. We never touch
1329 * journal structures from interrupts.
1332 static inline handle_t *journal_current_handle(void)
1334 return current->journal_info;
1337 /* The journaling code user interface:
1339 * Create and destroy handles
1340 * Register buffer modifications against the current transaction.
1343 extern handle_t *jbd2_journal_start(journal_t *, int nblocks);
1344 extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks,
1345 gfp_t gfp_mask, unsigned int type,
1346 unsigned int line_no);
1347 extern int jbd2_journal_restart(handle_t *, int nblocks);
1348 extern int jbd2__journal_restart(handle_t *, int nblocks, gfp_t gfp_mask);
1349 extern int jbd2_journal_start_reserved(handle_t *handle,
1350 unsigned int type, unsigned int line_no);
1351 extern void jbd2_journal_free_reserved(handle_t *handle);
1352 extern int jbd2_journal_extend (handle_t *, int nblocks);
1353 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *);
1354 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *);
1355 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *);
1356 void jbd2_journal_set_triggers(struct buffer_head *,
1357 struct jbd2_buffer_trigger_type *type);
1358 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *);
1359 extern int jbd2_journal_forget (handle_t *, struct buffer_head *);
1360 extern void journal_sync_buffer (struct buffer_head *);
1361 extern int jbd2_journal_invalidatepage(journal_t *,
1362 struct page *, unsigned int, unsigned int);
1363 extern int jbd2_journal_try_to_free_buffers(journal_t *, struct page *, gfp_t);
1364 extern int jbd2_journal_stop(handle_t *);
1365 extern int jbd2_journal_flush (journal_t *);
1366 extern void jbd2_journal_lock_updates (journal_t *);
1367 extern void jbd2_journal_unlock_updates (journal_t *);
1369 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev,
1370 struct block_device *fs_dev,
1371 unsigned long long start, int len, int bsize);
1372 extern journal_t * jbd2_journal_init_inode (struct inode *);
1373 extern int jbd2_journal_update_format (journal_t *);
1374 extern int jbd2_journal_check_used_features
1375 (journal_t *, unsigned long, unsigned long, unsigned long);
1376 extern int jbd2_journal_check_available_features
1377 (journal_t *, unsigned long, unsigned long, unsigned long);
1378 extern int jbd2_journal_set_features
1379 (journal_t *, unsigned long, unsigned long, unsigned long);
1380 extern void jbd2_journal_clear_features
1381 (journal_t *, unsigned long, unsigned long, unsigned long);
1382 extern int jbd2_journal_load (journal_t *journal);
1383 extern int jbd2_journal_destroy (journal_t *);
1384 extern int jbd2_journal_recover (journal_t *journal);
1385 extern int jbd2_journal_wipe (journal_t *, int);
1386 extern int jbd2_journal_skip_recovery (journal_t *);
1387 extern void jbd2_journal_update_sb_errno(journal_t *);
1388 extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t,
1389 unsigned long, int);
1390 extern void __jbd2_journal_abort_hard (journal_t *);
1391 extern void jbd2_journal_abort (journal_t *, int);
1392 extern int jbd2_journal_errno (journal_t *);
1393 extern void jbd2_journal_ack_err (journal_t *);
1394 extern int jbd2_journal_clear_err (journal_t *);
1395 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *);
1396 extern int jbd2_journal_force_commit(journal_t *);
1397 extern int jbd2_journal_force_commit_nested(journal_t *);
1398 extern int jbd2_journal_inode_add_write(handle_t *handle, struct jbd2_inode *inode);
1399 extern int jbd2_journal_inode_add_wait(handle_t *handle, struct jbd2_inode *inode);
1400 extern int jbd2_journal_begin_ordered_truncate(journal_t *journal,
1401 struct jbd2_inode *inode, loff_t new_size);
1402 extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode);
1403 extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode);
1406 * journal_head management
1408 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh);
1409 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh);
1410 void jbd2_journal_put_journal_head(struct journal_head *jh);
1415 extern struct kmem_cache *jbd2_handle_cache;
1417 static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags)
1419 return kmem_cache_zalloc(jbd2_handle_cache, gfp_flags);
1422 static inline void jbd2_free_handle(handle_t *handle)
1424 kmem_cache_free(jbd2_handle_cache, handle);
1428 * jbd2_inode management (optional, for those file systems that want to use
1429 * dynamically allocated jbd2_inode structures)
1431 extern struct kmem_cache *jbd2_inode_cache;
1433 static inline struct jbd2_inode *jbd2_alloc_inode(gfp_t gfp_flags)
1435 return kmem_cache_alloc(jbd2_inode_cache, gfp_flags);
1438 static inline void jbd2_free_inode(struct jbd2_inode *jinode)
1440 kmem_cache_free(jbd2_inode_cache, jinode);
1443 /* Primary revoke support */
1444 #define JOURNAL_REVOKE_DEFAULT_HASH 256
1445 extern int jbd2_journal_init_revoke(journal_t *, int);
1446 extern void jbd2_journal_destroy_revoke_record_cache(void);
1447 extern void jbd2_journal_destroy_revoke_table_cache(void);
1448 extern int __init jbd2_journal_init_revoke_record_cache(void);
1449 extern int __init jbd2_journal_init_revoke_table_cache(void);
1451 extern void jbd2_journal_destroy_revoke(journal_t *);
1452 extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *);
1453 extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *);
1454 extern void jbd2_journal_write_revoke_records(transaction_t *transaction,
1455 struct list_head *log_bufs);
1457 /* Recovery revoke support */
1458 extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t);
1459 extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t);
1460 extern void jbd2_journal_clear_revoke(journal_t *);
1461 extern void jbd2_journal_switch_revoke_table(journal_t *journal);
1462 extern void jbd2_clear_buffer_revoked_flags(journal_t *journal);
1465 * The log thread user interface:
1467 * Request space in the current transaction, and force transaction commit
1468 * transitions on demand.
1471 int jbd2_log_start_commit(journal_t *journal, tid_t tid);
1472 int __jbd2_log_start_commit(journal_t *journal, tid_t tid);
1473 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid);
1474 int jbd2_log_wait_commit(journal_t *journal, tid_t tid);
1475 int jbd2_transaction_committed(journal_t *journal, tid_t tid);
1476 int jbd2_complete_transaction(journal_t *journal, tid_t tid);
1477 int jbd2_log_do_checkpoint(journal_t *journal);
1478 int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid);
1480 void __jbd2_log_wait_for_space(journal_t *journal);
1481 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *);
1482 extern int jbd2_cleanup_journal_tail(journal_t *);
1487 * Simple test wrapper function to test the JBD2_ABORT state flag. This
1488 * bit, when set, indicates that we have had a fatal error somewhere,
1489 * either inside the journaling layer or indicated to us by the client
1490 * (eg. ext3), and that we and should not commit any further
1494 static inline int is_journal_aborted(journal_t *journal)
1496 return journal->j_flags & JBD2_ABORT;
1499 static inline int is_handle_aborted(handle_t *handle)
1501 if (handle->h_aborted || !handle->h_transaction)
1503 return is_journal_aborted(handle->h_transaction->t_journal);
1506 static inline void jbd2_journal_abort_handle(handle_t *handle)
1508 handle->h_aborted = 1;
1511 #endif /* __KERNEL__ */
1513 /* Comparison functions for transaction IDs: perform comparisons using
1514 * modulo arithmetic so that they work over sequence number wraps. */
1516 static inline int tid_gt(tid_t x, tid_t y)
1518 int difference = (x - y);
1519 return (difference > 0);
1522 static inline int tid_geq(tid_t x, tid_t y)
1524 int difference = (x - y);
1525 return (difference >= 0);
1528 extern int jbd2_journal_blocks_per_page(struct inode *inode);
1529 extern size_t journal_tag_bytes(journal_t *journal);
1531 static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j)
1533 return jbd2_has_feature_csum2(j) || jbd2_has_feature_csum3(j);
1536 static inline int jbd2_journal_has_csum_v2or3(journal_t *journal)
1538 WARN_ON_ONCE(jbd2_journal_has_csum_v2or3_feature(journal) &&
1539 journal->j_chksum_driver == NULL);
1541 return journal->j_chksum_driver != NULL;
1545 * We reserve t_outstanding_credits >> JBD2_CONTROL_BLOCKS_SHIFT for
1546 * transaction control blocks.
1548 #define JBD2_CONTROL_BLOCKS_SHIFT 5
1551 * Return the minimum number of blocks which must be free in the journal
1552 * before a new transaction may be started. Must be called under j_state_lock.
1554 static inline int jbd2_space_needed(journal_t *journal)
1556 int nblocks = journal->j_max_transaction_buffers;
1557 return nblocks + (nblocks >> JBD2_CONTROL_BLOCKS_SHIFT);
1561 * Return number of free blocks in the log. Must be called under j_state_lock.
1563 static inline unsigned long jbd2_log_space_left(journal_t *journal)
1565 /* Allow for rounding errors */
1566 unsigned long free = journal->j_free - 32;
1568 if (journal->j_committing_transaction) {
1569 unsigned long committing = atomic_read(&journal->
1570 j_committing_transaction->t_outstanding_credits);
1572 /* Transaction + control blocks */
1573 free -= committing + (committing >> JBD2_CONTROL_BLOCKS_SHIFT);
1579 * Definitions which augment the buffer_head layer
1582 /* journaling buffer types */
1583 #define BJ_None 0 /* Not journaled */
1584 #define BJ_Metadata 1 /* Normal journaled metadata */
1585 #define BJ_Forget 2 /* Buffer superseded by this transaction */
1586 #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */
1587 #define BJ_Reserved 4 /* Buffer is reserved for access by journal */
1590 extern int jbd_blocks_per_page(struct inode *inode);
1592 /* JBD uses a CRC32 checksum */
1593 #define JBD_MAX_CHECKSUM_SIZE 4
1595 static inline u32 jbd2_chksum(journal_t *journal, u32 crc,
1596 const void *address, unsigned int length)
1599 struct shash_desc shash;
1600 char ctx[JBD_MAX_CHECKSUM_SIZE];
1604 BUG_ON(crypto_shash_descsize(journal->j_chksum_driver) >
1605 JBD_MAX_CHECKSUM_SIZE);
1607 desc.shash.tfm = journal->j_chksum_driver;
1608 *(u32 *)desc.ctx = crc;
1610 err = crypto_shash_update(&desc.shash, address, length);
1613 return *(u32 *)desc.ctx;
1616 /* Return most recent uncommitted transaction */
1617 static inline tid_t jbd2_get_latest_transaction(journal_t *journal)
1621 read_lock(&journal->j_state_lock);
1622 tid = journal->j_commit_request;
1623 if (journal->j_running_transaction)
1624 tid = journal->j_running_transaction->t_tid;
1625 read_unlock(&journal->j_state_lock);
1631 #define buffer_trace_init(bh) do {} while (0)
1632 #define print_buffer_fields(bh) do {} while (0)
1633 #define print_buffer_trace(bh) do {} while (0)
1634 #define BUFFER_TRACE(bh, info) do {} while (0)
1635 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0)
1636 #define JBUFFER_TRACE(jh, info) do {} while (0)
1638 #endif /* __KERNEL__ */
1640 #define EFSBADCRC EBADMSG /* Bad CRC detected */
1641 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
1643 #endif /* _LINUX_JBD2_H */