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 <linux/blkdev.h>
31 #include <crypto/hash.h>
34 #define journal_oom_retry 1
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.
43 #undef JBD2_PARANOID_IOFAIL
46 * The default maximum commit age, in seconds.
48 #define JBD2_DEFAULT_MAX_COMMIT_AGE 5
50 #ifdef CONFIG_JBD2_DEBUG
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.
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, ...);
61 #define jbd_debug(n, fmt, a...) \
62 __jbd2_debug((n), __FILE__, __func__, __LINE__, (fmt), ##a)
64 #define jbd_debug(n, fmt, a...) /**/
67 extern void *jbd2_alloc(size_t size, gfp_t flags);
68 extern void jbd2_free(void *ptr, size_t size);
70 #define JBD2_MIN_JOURNAL_BLOCKS 1024
75 * typedef handle_t - The handle_t type represents a single atomic update being performed by some process.
77 * All filesystem modifications made by the process go
78 * through this handle. Recursive operations (such as quota operations)
79 * are gathered into a single update.
81 * The buffer credits field is used to account for journaled buffers
82 * being modified by the running process. To ensure that there is
83 * enough log space for all outstanding operations, we need to limit the
84 * number of outstanding buffers possible at any time. When the
85 * operation completes, any buffer credits not used are credited back to
86 * the transaction, so that at all times we know how many buffers the
87 * outstanding updates on a transaction might possibly touch.
89 * This is an opaque datatype.
91 typedef struct jbd2_journal_handle handle_t; /* Atomic operation type */
95 * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem.
97 * journal_t is linked to from the fs superblock structure.
99 * We use the journal_t to keep track of all outstanding transaction
100 * activity on the filesystem, and to manage the state of the log
103 * This is an opaque datatype.
105 typedef struct journal_s journal_t; /* Journal control structure */
109 * Internal structures used by the logging mechanism:
112 #define JBD2_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */
119 * Descriptor block types:
122 #define JBD2_DESCRIPTOR_BLOCK 1
123 #define JBD2_COMMIT_BLOCK 2
124 #define JBD2_SUPERBLOCK_V1 3
125 #define JBD2_SUPERBLOCK_V2 4
126 #define JBD2_REVOKE_BLOCK 5
129 * Standard header for all descriptor blocks:
131 typedef struct journal_header_s
141 #define JBD2_CRC32_CHKSUM 1
142 #define JBD2_MD5_CHKSUM 2
143 #define JBD2_SHA1_CHKSUM 3
144 #define JBD2_CRC32C_CHKSUM 4
146 #define JBD2_CRC32_CHKSUM_SIZE 4
148 #define JBD2_CHECKSUM_BYTES (32 / sizeof(u32))
150 * Commit block header for storing transactional checksums:
152 * NOTE: If FEATURE_COMPAT_CHECKSUM (checksum v1) is set, the h_chksum*
153 * fields are used to store a checksum of the descriptor and data blocks.
155 * If FEATURE_INCOMPAT_CSUM_V2 (checksum v2) is set, then the h_chksum
156 * field is used to store crc32c(uuid+commit_block). Each journal metadata
157 * block gets its own checksum, and data block checksums are stored in
158 * journal_block_tag (in the descriptor). The other h_chksum* fields are
161 * If FEATURE_INCOMPAT_CSUM_V3 is set, the descriptor block uses
162 * journal_block_tag3_t to store a full 32-bit checksum. Everything else
165 * Checksum v1, v2, and v3 are mutually exclusive features.
167 struct commit_header {
171 unsigned char h_chksum_type;
172 unsigned char h_chksum_size;
173 unsigned char h_padding[2];
174 __be32 h_chksum[JBD2_CHECKSUM_BYTES];
176 __be32 h_commit_nsec;
180 * The block tag: used to describe a single buffer in the journal.
181 * t_blocknr_high is only used if INCOMPAT_64BIT is set, so this
182 * raw struct shouldn't be used for pointer math or sizeof() - use
183 * journal_tag_bytes(journal) instead to compute this.
185 typedef struct journal_block_tag3_s
187 __be32 t_blocknr; /* The on-disk block number */
188 __be32 t_flags; /* See below */
189 __be32 t_blocknr_high; /* most-significant high 32bits. */
190 __be32 t_checksum; /* crc32c(uuid+seq+block) */
191 } journal_block_tag3_t;
193 typedef struct journal_block_tag_s
195 __be32 t_blocknr; /* The on-disk block number */
196 __be16 t_checksum; /* truncated crc32c(uuid+seq+block) */
197 __be16 t_flags; /* See below */
198 __be32 t_blocknr_high; /* most-significant high 32bits. */
199 } journal_block_tag_t;
201 /* Tail of descriptor or revoke block, for checksumming */
202 struct jbd2_journal_block_tail {
203 __be32 t_checksum; /* crc32c(uuid+descr_block) */
207 * The revoke descriptor: used on disk to describe a series of blocks to
208 * be revoked from the log
210 typedef struct jbd2_journal_revoke_header_s
212 journal_header_t r_header;
213 __be32 r_count; /* Count of bytes used in the block */
214 } jbd2_journal_revoke_header_t;
216 /* Definitions for the journal tag flags word: */
217 #define JBD2_FLAG_ESCAPE 1 /* on-disk block is escaped */
218 #define JBD2_FLAG_SAME_UUID 2 /* block has same uuid as previous */
219 #define JBD2_FLAG_DELETED 4 /* block deleted by this transaction */
220 #define JBD2_FLAG_LAST_TAG 8 /* last tag in this descriptor block */
224 * The journal superblock. All fields are in big-endian byte order.
226 typedef struct journal_superblock_s
229 journal_header_t s_header;
232 /* Static information describing the journal */
233 __be32 s_blocksize; /* journal device blocksize */
234 __be32 s_maxlen; /* total blocks in journal file */
235 __be32 s_first; /* first block of log information */
238 /* Dynamic information describing the current state of the log */
239 __be32 s_sequence; /* first commit ID expected in log */
240 __be32 s_start; /* blocknr of start of log */
243 /* Error value, as set by jbd2_journal_abort(). */
247 /* Remaining fields are only valid in a version-2 superblock */
248 __be32 s_feature_compat; /* compatible feature set */
249 __be32 s_feature_incompat; /* incompatible feature set */
250 __be32 s_feature_ro_compat; /* readonly-compatible feature set */
252 __u8 s_uuid[16]; /* 128-bit uuid for journal */
255 __be32 s_nr_users; /* Nr of filesystems sharing log */
257 __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/
260 __be32 s_max_transaction; /* Limit of journal blocks per trans.*/
261 __be32 s_max_trans_data; /* Limit of data blocks per trans. */
264 __u8 s_checksum_type; /* checksum type */
267 __be32 s_checksum; /* crc32c(superblock) */
270 __u8 s_users[16*48]; /* ids of all fs'es sharing the log */
272 } journal_superblock_t;
274 /* Use the jbd2_{has,set,clear}_feature_* helpers; these will be removed */
275 #define JBD2_HAS_COMPAT_FEATURE(j,mask) \
276 ((j)->j_format_version >= 2 && \
277 ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask))))
278 #define JBD2_HAS_RO_COMPAT_FEATURE(j,mask) \
279 ((j)->j_format_version >= 2 && \
280 ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask))))
281 #define JBD2_HAS_INCOMPAT_FEATURE(j,mask) \
282 ((j)->j_format_version >= 2 && \
283 ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask))))
285 #define JBD2_FEATURE_COMPAT_CHECKSUM 0x00000001
287 #define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001
288 #define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002
289 #define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT 0x00000004
290 #define JBD2_FEATURE_INCOMPAT_CSUM_V2 0x00000008
291 #define JBD2_FEATURE_INCOMPAT_CSUM_V3 0x00000010
293 /* See "journal feature predicate functions" below */
295 /* Features known to this kernel version: */
296 #define JBD2_KNOWN_COMPAT_FEATURES JBD2_FEATURE_COMPAT_CHECKSUM
297 #define JBD2_KNOWN_ROCOMPAT_FEATURES 0
298 #define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \
299 JBD2_FEATURE_INCOMPAT_64BIT | \
300 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | \
301 JBD2_FEATURE_INCOMPAT_CSUM_V2 | \
302 JBD2_FEATURE_INCOMPAT_CSUM_V3)
306 #include <linux/fs.h>
307 #include <linux/sched.h>
309 enum jbd_state_bits {
310 BH_JBD /* Has an attached ext3 journal_head */
312 BH_JWrite, /* Being written to log (@@@ DEBUGGING) */
313 BH_Freed, /* Has been freed (truncated) */
314 BH_Revoked, /* Has been revoked from the log */
315 BH_RevokeValid, /* Revoked flag is valid */
316 BH_JBDDirty, /* Is dirty but journaled */
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_journal_head(struct buffer_head *bh)
347 bit_spin_lock(BH_JournalHead, &bh->b_state);
350 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
352 bit_spin_unlock(BH_JournalHead, &bh->b_state);
355 #define J_ASSERT(assert) BUG_ON(!(assert))
357 #define J_ASSERT_BH(bh, expr) J_ASSERT(expr)
358 #define J_ASSERT_JH(jh, expr) J_ASSERT(expr)
360 #if defined(JBD2_PARANOID_IOFAIL)
361 #define J_EXPECT(expr, why...) J_ASSERT(expr)
362 #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr)
363 #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr)
365 #define __journal_expect(expr, why...) \
370 "JBD2 unexpected failure: %s: %s;\n", \
372 printk(KERN_ERR why "\n"); \
376 #define J_EXPECT(expr, why...) __journal_expect(expr, ## why)
377 #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why)
378 #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why)
381 /* Flags in jbd_inode->i_flags */
382 #define __JI_COMMIT_RUNNING 0
383 #define __JI_WRITE_DATA 1
384 #define __JI_WAIT_DATA 2
387 * Commit of the inode data in progress. We use this flag to protect us from
388 * concurrent deletion of inode. We cannot use reference to inode for this
389 * since we cannot afford doing last iput() on behalf of kjournald
391 #define JI_COMMIT_RUNNING (1 << __JI_COMMIT_RUNNING)
392 /* Write allocated dirty buffers in this inode before commit */
393 #define JI_WRITE_DATA (1 << __JI_WRITE_DATA)
394 /* Wait for outstanding data writes for this inode before commit */
395 #define JI_WAIT_DATA (1 << __JI_WAIT_DATA)
398 * struct jbd_inode - The jbd_inode type is the structure linking inodes in
399 * ordered mode present in a transaction so that we can sync them during commit.
405 * Which transaction does this inode belong to? Either the running
406 * transaction or the committing one. [j_list_lock]
408 transaction_t *i_transaction;
411 * @i_next_transaction:
413 * Pointer to the running transaction modifying inode's data in case
414 * there is already a committing transaction touching it. [j_list_lock]
416 transaction_t *i_next_transaction;
419 * @i_list: List of inodes in the i_transaction [j_list_lock]
421 struct list_head i_list;
426 * VFS inode this inode belongs to [constant for lifetime of structure]
428 struct inode *i_vfs_inode;
431 * @i_flags: Flags of inode [j_list_lock]
433 unsigned long i_flags;
438 * Offset in bytes where the dirty range for this inode starts.
441 loff_t i_dirty_start;
446 * Inclusive offset in bytes where the dirty range for this inode
447 * ends. [j_list_lock]
452 struct jbd2_revoke_table_s;
455 * struct jbd2_journal_handle - The jbd2_journal_handle type is the concrete
456 * type associated with handle_t.
457 * @h_transaction: Which compound transaction is this update a part of?
458 * @h_journal: Which journal handle belongs to - used iff h_reserved set.
459 * @h_rsv_handle: Handle reserved for finishing the logical operation.
460 * @h_total_credits: Number of remaining buffers we are allowed to add to
461 * journal. These are dirty buffers and revoke descriptor blocks.
462 * @h_revoke_credits: Number of remaining revoke records available for handle
463 * @h_ref: Reference count on this handle.
464 * @h_err: Field for caller's use to track errors through large fs operations.
465 * @h_sync: Flag for sync-on-close.
466 * @h_jdata: Flag to force data journaling.
467 * @h_reserved: Flag for handle for reserved credits.
468 * @h_aborted: Flag indicating fatal error on handle.
469 * @h_type: For handle statistics.
470 * @h_line_no: For handle statistics.
471 * @h_start_jiffies: Handle Start time.
472 * @h_requested_credits: Holds @h_total_credits after handle is started.
473 * @h_revoke_credits_requested: Holds @h_revoke_credits after handle is started.
474 * @saved_alloc_context: Saved context while transaction is open.
477 /* Docbook can't yet cope with the bit fields, but will leave the documentation
478 * in so it can be fixed later.
481 struct jbd2_journal_handle
484 transaction_t *h_transaction;
485 /* Which journal handle belongs to - used iff h_reserved set */
486 journal_t *h_journal;
489 handle_t *h_rsv_handle;
491 int h_revoke_credits;
492 int h_revoke_credits_requested;
496 /* Flags [no locking] */
497 unsigned int h_sync: 1;
498 unsigned int h_jdata: 1;
499 unsigned int h_reserved: 1;
500 unsigned int h_aborted: 1;
501 unsigned int h_type: 8;
502 unsigned int h_line_no: 16;
504 unsigned long h_start_jiffies;
505 unsigned int h_requested_credits;
507 unsigned int saved_alloc_context;
512 * Some stats for checkpoint phase
514 struct transaction_chp_stats_s {
515 unsigned long cs_chp_time;
516 __u32 cs_forced_to_close;
521 /* The transaction_t type is the guts of the journaling mechanism. It
522 * tracks a compound transaction through its various states:
524 * RUNNING: accepting new updates
525 * LOCKED: Updates still running but we don't accept new ones
526 * RUNDOWN: Updates are tidying up but have finished requesting
527 * new buffers to modify (state not used for now)
528 * FLUSH: All updates complete, but we are still writing to disk
529 * COMMIT: All data on disk, writing commit record
530 * FINISHED: We still have to keep the transaction for checkpointing.
532 * The transaction keeps track of all of the buffers modified by a
533 * running transaction, and all of the buffers committed but not yet
534 * flushed to home for finished transactions.
541 * ->jbd_lock_bh_journal_head() (This is "innermost")
553 * ->j_list_lock (journal_unmap_buffer)
559 /* Pointer to the journal for this transaction. [no locking] */
560 journal_t *t_journal;
562 /* Sequence number for this transaction [no locking] */
566 * Transaction's current state
567 * [no locking - only kjournald2 alters this]
568 * [j_list_lock] guards transition of a transaction into T_FINISHED
569 * state and subsequent call of __jbd2_journal_drop_transaction()
570 * FIXME: needs barriers
571 * KLUDGE: [use j_state_lock]
586 * Where in the log does this transaction's commit start? [no locking]
588 unsigned long t_log_start;
590 /* Number of buffers on the t_buffers list [j_list_lock] */
594 * Doubly-linked circular list of all buffers reserved but not yet
595 * modified by this transaction [j_list_lock]
597 struct journal_head *t_reserved_list;
600 * Doubly-linked circular list of all metadata buffers owned by this
601 * transaction [j_list_lock]
603 struct journal_head *t_buffers;
606 * Doubly-linked circular list of all forget buffers (superseded
607 * buffers which we can un-checkpoint once this transaction commits)
610 struct journal_head *t_forget;
613 * Doubly-linked circular list of all buffers still to be flushed before
614 * this transaction can be checkpointed. [j_list_lock]
616 struct journal_head *t_checkpoint_list;
619 * Doubly-linked circular list of all buffers submitted for IO while
620 * checkpointing. [j_list_lock]
622 struct journal_head *t_checkpoint_io_list;
625 * Doubly-linked circular list of metadata buffers being shadowed by log
626 * IO. The IO buffers on the iobuf list and the shadow buffers on this
627 * list match each other one for one at all times. [j_list_lock]
629 struct journal_head *t_shadow_list;
632 * List of inodes associated with the transaction; e.g., ext4 uses
633 * this to track inodes in data=ordered and data=journal mode that
634 * need special handling on transaction commit; also used by ocfs2.
637 struct list_head t_inode_list;
640 * Protects info related to handles
642 spinlock_t t_handle_lock;
645 * Longest time some handle had to wait for running transaction
647 unsigned long t_max_wait;
650 * When transaction started
652 unsigned long t_start;
655 * When commit was requested
657 unsigned long t_requested;
660 * Checkpointing stats [j_checkpoint_sem]
662 struct transaction_chp_stats_s t_chp_stats;
665 * Number of outstanding updates running on this transaction
671 * Number of blocks reserved for this transaction in the journal.
672 * This is including all credits reserved when starting transaction
673 * handles as well as all journal descriptor blocks needed for this
674 * transaction. [none]
676 atomic_t t_outstanding_credits;
679 * Number of revoke records for this transaction added by already
680 * stopped handles. [none]
682 atomic_t t_outstanding_revokes;
685 * How many handles used this transaction? [none]
687 atomic_t t_handle_count;
690 * Forward and backward links for the circular list of all transactions
691 * awaiting checkpoint. [j_list_lock]
693 transaction_t *t_cpnext, *t_cpprev;
696 * When will the transaction expire (become due for commit), in jiffies?
699 unsigned long t_expires;
702 * When this transaction started, in nanoseconds [no locking]
704 ktime_t t_start_time;
707 * This transaction is being forced and some process is
708 * waiting for it to finish.
710 unsigned int t_synchronous_commit:1;
712 /* Disk flush needs to be sent to fs partition [no locking] */
713 int t_need_data_flush;
716 * For use by the filesystem to store fs-specific data
717 * structures associated with the transaction
719 struct list_head t_private_list;
722 struct transaction_run_stats_s {
723 unsigned long rs_wait;
724 unsigned long rs_request_delay;
725 unsigned long rs_running;
726 unsigned long rs_locked;
727 unsigned long rs_flushing;
728 unsigned long rs_logging;
730 __u32 rs_handle_count;
732 __u32 rs_blocks_logged;
735 struct transaction_stats_s {
736 unsigned long ts_tid;
737 unsigned long ts_requested;
738 struct transaction_run_stats_s run;
741 static inline unsigned long
742 jbd2_time_diff(unsigned long start, unsigned long end)
747 return end + (MAX_JIFFY_OFFSET - start);
750 #define JBD2_NR_BATCH 64
753 * struct journal_s - The journal_s type is the concrete type associated with
759 * @j_flags: General journaling state flags [j_state_lock]
761 unsigned long j_flags;
766 * Is there an outstanding uncleared error on the journal (from a prior
767 * abort)? [j_state_lock]
772 * @j_abort_mutex: Lock the whole aborting procedure.
774 struct mutex j_abort_mutex;
777 * @j_sb_buffer: The first part of the superblock buffer.
779 struct buffer_head *j_sb_buffer;
782 * @j_superblock: The second part of the superblock buffer.
784 journal_superblock_t *j_superblock;
787 * @j_format_version: Version of the superblock format.
789 int j_format_version;
792 * @j_state_lock: Protect the various scalars in the journal.
794 rwlock_t j_state_lock;
799 * Number of processes waiting to create a barrier lock [j_state_lock]
804 * @j_barrier: The barrier lock itself.
806 struct mutex j_barrier;
809 * @j_running_transaction:
811 * Transactions: The current running transaction...
812 * [j_state_lock] [caller holding open handle]
814 transaction_t *j_running_transaction;
817 * @j_committing_transaction:
819 * the transaction we are pushing to disk
820 * [j_state_lock] [caller holding open handle]
822 transaction_t *j_committing_transaction;
825 * @j_checkpoint_transactions:
827 * ... and a linked circular list of all transactions waiting for
828 * checkpointing. [j_list_lock]
830 transaction_t *j_checkpoint_transactions;
833 * @j_wait_transaction_locked:
835 * Wait queue for waiting for a locked transaction to start committing,
836 * or for a barrier lock to be released.
838 wait_queue_head_t j_wait_transaction_locked;
841 * @j_wait_done_commit: Wait queue for waiting for commit to complete.
843 wait_queue_head_t j_wait_done_commit;
846 * @j_wait_commit: Wait queue to trigger commit.
848 wait_queue_head_t j_wait_commit;
851 * @j_wait_updates: Wait queue to wait for updates to complete.
853 wait_queue_head_t j_wait_updates;
858 * Wait queue to wait for reserved buffer credits to drop.
860 wait_queue_head_t j_wait_reserved;
863 * @j_checkpoint_mutex:
865 * Semaphore for locking against concurrent checkpoints.
867 struct mutex j_checkpoint_mutex;
872 * List of buffer heads used by the checkpoint routine. This
873 * was moved from jbd2_log_do_checkpoint() to reduce stack
874 * usage. Access to this array is controlled by the
875 * @j_checkpoint_mutex. [j_checkpoint_mutex]
877 struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH];
882 * Journal head: identifies the first unused block in the journal.
885 unsigned long j_head;
890 * Journal tail: identifies the oldest still-used block in the journal.
893 unsigned long j_tail;
898 * Journal free: how many free blocks are there in the journal?
901 unsigned long j_free;
906 * The block number of the first usable block in the journal
909 unsigned long j_first;
914 * The block number one beyond the last usable block in the journal
917 unsigned long j_last;
920 * @j_dev: Device where we store the journal.
922 struct block_device *j_dev;
925 * @j_blocksize: Block size for the location where we store the journal.
932 * Starting block offset into the device where we store the journal.
934 unsigned long long j_blk_offset;
937 * @j_devname: Journal device name.
939 char j_devname[BDEVNAME_SIZE+24];
944 * Device which holds the client fs. For internal journal this will be
947 struct block_device *j_fs_dev;
950 * @j_maxlen: Total maximum capacity of the journal region on disk.
952 unsigned int j_maxlen;
955 * @j_reserved_credits:
957 * Number of buffers reserved from the running transaction.
959 atomic_t j_reserved_credits;
962 * @j_list_lock: Protects the buffer lists and internal buffer state.
964 spinlock_t j_list_lock;
969 * Optional inode where we store the journal. If present, all
970 * journal block numbers are mapped into this inode via bmap().
972 struct inode *j_inode;
977 * Sequence number of the oldest transaction in the log [j_state_lock]
979 tid_t j_tail_sequence;
982 * @j_transaction_sequence:
984 * Sequence number of the next transaction to grant [j_state_lock]
986 tid_t j_transaction_sequence;
989 * @j_commit_sequence:
991 * Sequence number of the most recently committed transaction
994 tid_t j_commit_sequence;
999 * Sequence number of the most recent transaction wanting commit
1002 tid_t j_commit_request;
1007 * Journal uuid: identifies the object (filesystem, LVM volume etc)
1008 * backed by this journal. This will eventually be replaced by an array
1009 * of uuids, allowing us to index multiple devices within a single
1010 * journal and to perform atomic updates across them.
1015 * @j_task: Pointer to the current commit thread for this journal.
1017 struct task_struct *j_task;
1020 * @j_max_transaction_buffers:
1022 * Maximum number of metadata buffers to allow in a single compound
1023 * commit transaction.
1025 int j_max_transaction_buffers;
1028 * @j_revoke_records_per_block:
1030 * Number of revoke records that fit in one descriptor block.
1032 int j_revoke_records_per_block;
1035 * @j_commit_interval:
1037 * What is the maximum transaction lifetime before we begin a commit?
1039 unsigned long j_commit_interval;
1042 * @j_commit_timer: The timer used to wakeup the commit thread.
1044 struct timer_list j_commit_timer;
1047 * @j_revoke_lock: Protect the revoke table.
1049 spinlock_t j_revoke_lock;
1054 * The revoke table - maintains the list of revoked blocks in the
1055 * current transaction.
1057 struct jbd2_revoke_table_s *j_revoke;
1060 * @j_revoke_table: Alternate revoke tables for j_revoke.
1062 struct jbd2_revoke_table_s *j_revoke_table[2];
1065 * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction.
1067 struct buffer_head **j_wbuf;
1072 * Size of @j_wbuf array.
1077 * @j_last_sync_writer:
1079 * The pid of the last person to run a synchronous operation
1080 * through the journal.
1082 pid_t j_last_sync_writer;
1085 * @j_average_commit_time:
1087 * The average amount of time in nanoseconds it takes to commit a
1088 * transaction to disk. [j_state_lock]
1090 u64 j_average_commit_time;
1093 * @j_min_batch_time:
1095 * Minimum time that we should wait for additional filesystem operations
1096 * to get batched into a synchronous handle in microseconds.
1098 u32 j_min_batch_time;
1101 * @j_max_batch_time:
1103 * Maximum time that we should wait for additional filesystem operations
1104 * to get batched into a synchronous handle in microseconds.
1106 u32 j_max_batch_time;
1109 * @j_commit_callback:
1111 * This function is called when a transaction is closed.
1113 void (*j_commit_callback)(journal_t *,
1117 * @j_submit_inode_data_buffers:
1119 * This function is called for all inodes associated with the
1120 * committing transaction marked with JI_WRITE_DATA flag
1121 * before we start to write out the transaction to the journal.
1123 int (*j_submit_inode_data_buffers)
1124 (struct jbd2_inode *);
1127 * @j_finish_inode_data_buffers:
1129 * This function is called for all inodes associated with the
1130 * committing transaction marked with JI_WAIT_DATA flag
1131 * after we have written the transaction to the journal
1132 * but before we write out the commit block.
1134 int (*j_finish_inode_data_buffers)
1135 (struct jbd2_inode *);
1138 * Journal statistics
1142 * @j_history_lock: Protect the transactions statistics history.
1144 spinlock_t j_history_lock;
1147 * @j_proc_entry: procfs entry for the jbd statistics directory.
1149 struct proc_dir_entry *j_proc_entry;
1152 * @j_stats: Overall statistics.
1154 struct transaction_stats_s j_stats;
1157 * @j_failed_commit: Failed journal commit ID.
1159 unsigned int j_failed_commit;
1164 * An opaque pointer to fs-private information. ext3 puts its
1165 * superblock pointer here.
1172 * Reference to checksum algorithm driver via cryptoapi.
1174 struct crypto_shash *j_chksum_driver;
1179 * Precomputed journal UUID checksum for seeding other checksums.
1183 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1185 * @j_trans_commit_map:
1187 * Lockdep entity to track transaction commit dependencies. Handles
1188 * hold this "lock" for read, when we wait for commit, we acquire the
1189 * "lock" for writing. This matches the properties of jbd2 journalling
1190 * where the running transaction has to wait for all handles to be
1191 * dropped to commit that transaction and also acquiring a handle may
1192 * require transaction commit to finish.
1194 struct lockdep_map j_trans_commit_map;
1198 #define jbd2_might_wait_for_commit(j) \
1200 rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \
1201 rwsem_release(&j->j_trans_commit_map, _THIS_IP_); \
1204 /* journal feature predicate functions */
1205 #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \
1206 static inline bool jbd2_has_feature_##name(journal_t *j) \
1208 return ((j)->j_format_version >= 2 && \
1209 ((j)->j_superblock->s_feature_compat & \
1210 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \
1212 static inline void jbd2_set_feature_##name(journal_t *j) \
1214 (j)->j_superblock->s_feature_compat |= \
1215 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \
1217 static inline void jbd2_clear_feature_##name(journal_t *j) \
1219 (j)->j_superblock->s_feature_compat &= \
1220 ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \
1223 #define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1224 static inline bool jbd2_has_feature_##name(journal_t *j) \
1226 return ((j)->j_format_version >= 2 && \
1227 ((j)->j_superblock->s_feature_ro_compat & \
1228 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \
1230 static inline void jbd2_set_feature_##name(journal_t *j) \
1232 (j)->j_superblock->s_feature_ro_compat |= \
1233 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \
1235 static inline void jbd2_clear_feature_##name(journal_t *j) \
1237 (j)->j_superblock->s_feature_ro_compat &= \
1238 ~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \
1241 #define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1242 static inline bool jbd2_has_feature_##name(journal_t *j) \
1244 return ((j)->j_format_version >= 2 && \
1245 ((j)->j_superblock->s_feature_incompat & \
1246 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \
1248 static inline void jbd2_set_feature_##name(journal_t *j) \
1250 (j)->j_superblock->s_feature_incompat |= \
1251 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \
1253 static inline void jbd2_clear_feature_##name(journal_t *j) \
1255 (j)->j_superblock->s_feature_incompat &= \
1256 ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \
1259 JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM)
1261 JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE)
1262 JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT)
1263 JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT)
1264 JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2)
1265 JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3)
1268 * Journal flag definitions
1270 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */
1271 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */
1272 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */
1273 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */
1274 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */
1275 #define JBD2_BARRIER 0x020 /* Use IDE barriers */
1276 #define JBD2_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file
1277 * data write error in ordered
1281 * Function declarations for the journaling transaction and buffer
1285 /* Filing buffers */
1286 extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *);
1287 extern bool __jbd2_journal_refile_buffer(struct journal_head *);
1288 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *);
1289 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
1290 extern void __journal_free_buffer(struct journal_head *bh);
1291 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
1292 extern void __journal_clean_data_list(transaction_t *transaction);
1293 static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh)
1295 list_add_tail(&bh->b_assoc_buffers, head);
1297 static inline void jbd2_unfile_log_bh(struct buffer_head *bh)
1299 list_del_init(&bh->b_assoc_buffers);
1302 /* Log buffer allocation */
1303 struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int);
1304 void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *);
1305 int jbd2_journal_next_log_block(journal_t *, unsigned long long *);
1306 int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid,
1307 unsigned long *block);
1308 int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block);
1309 void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block);
1311 /* Commit management */
1312 extern void jbd2_journal_commit_transaction(journal_t *);
1314 /* Checkpoint list management */
1315 void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy);
1316 int __jbd2_journal_remove_checkpoint(struct journal_head *);
1317 void jbd2_journal_destroy_checkpoint(journal_t *journal);
1318 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *);
1325 struct jbd2_buffer_trigger_type {
1327 * Fired a the moment data to write to the journal are known to be
1328 * stable - so either at the moment b_frozen_data is created or just
1329 * before a buffer is written to the journal. mapped_data is a mapped
1330 * buffer that is the frozen data for commit.
1332 void (*t_frozen)(struct jbd2_buffer_trigger_type *type,
1333 struct buffer_head *bh, void *mapped_data,
1337 * Fired during journal abort for dirty buffers that will not be
1340 void (*t_abort)(struct jbd2_buffer_trigger_type *type,
1341 struct buffer_head *bh);
1344 extern void jbd2_buffer_frozen_trigger(struct journal_head *jh,
1346 struct jbd2_buffer_trigger_type *triggers);
1347 extern void jbd2_buffer_abort_trigger(struct journal_head *jh,
1348 struct jbd2_buffer_trigger_type *triggers);
1351 extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
1352 struct journal_head *jh_in,
1353 struct buffer_head **bh_out,
1356 /* Transaction locking */
1357 extern void __wait_on_journal (journal_t *);
1359 /* Transaction cache support */
1360 extern void jbd2_journal_destroy_transaction_cache(void);
1361 extern int __init jbd2_journal_init_transaction_cache(void);
1362 extern void jbd2_journal_free_transaction(transaction_t *);
1367 * We need to lock the journal during transaction state changes so that nobody
1368 * ever tries to take a handle on the running transaction while we are in the
1369 * middle of moving it to the commit phase. j_state_lock does this.
1371 * Note that the locking is completely interrupt unsafe. We never touch
1372 * journal structures from interrupts.
1375 static inline handle_t *journal_current_handle(void)
1377 return current->journal_info;
1380 /* The journaling code user interface:
1382 * Create and destroy handles
1383 * Register buffer modifications against the current transaction.
1386 extern handle_t *jbd2_journal_start(journal_t *, int nblocks);
1387 extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks,
1388 int revoke_records, gfp_t gfp_mask,
1389 unsigned int type, unsigned int line_no);
1390 extern int jbd2_journal_restart(handle_t *, int nblocks);
1391 extern int jbd2__journal_restart(handle_t *, int nblocks,
1392 int revoke_records, gfp_t gfp_mask);
1393 extern int jbd2_journal_start_reserved(handle_t *handle,
1394 unsigned int type, unsigned int line_no);
1395 extern void jbd2_journal_free_reserved(handle_t *handle);
1396 extern int jbd2_journal_extend(handle_t *handle, int nblocks,
1397 int revoke_records);
1398 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *);
1399 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *);
1400 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *);
1401 void jbd2_journal_set_triggers(struct buffer_head *,
1402 struct jbd2_buffer_trigger_type *type);
1403 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *);
1404 extern int jbd2_journal_forget (handle_t *, struct buffer_head *);
1405 extern int jbd2_journal_invalidatepage(journal_t *,
1406 struct page *, unsigned int, unsigned int);
1407 extern int jbd2_journal_try_to_free_buffers(journal_t *journal, struct page *page);
1408 extern int jbd2_journal_stop(handle_t *);
1409 extern int jbd2_journal_flush (journal_t *);
1410 extern void jbd2_journal_lock_updates (journal_t *);
1411 extern void jbd2_journal_unlock_updates (journal_t *);
1413 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev,
1414 struct block_device *fs_dev,
1415 unsigned long long start, int len, int bsize);
1416 extern journal_t * jbd2_journal_init_inode (struct inode *);
1417 extern int jbd2_journal_update_format (journal_t *);
1418 extern int jbd2_journal_check_used_features
1419 (journal_t *, unsigned long, unsigned long, unsigned long);
1420 extern int jbd2_journal_check_available_features
1421 (journal_t *, unsigned long, unsigned long, unsigned long);
1422 extern int jbd2_journal_set_features
1423 (journal_t *, unsigned long, unsigned long, unsigned long);
1424 extern void jbd2_journal_clear_features
1425 (journal_t *, unsigned long, unsigned long, unsigned long);
1426 extern int jbd2_journal_load (journal_t *journal);
1427 extern int jbd2_journal_destroy (journal_t *);
1428 extern int jbd2_journal_recover (journal_t *journal);
1429 extern int jbd2_journal_wipe (journal_t *, int);
1430 extern int jbd2_journal_skip_recovery (journal_t *);
1431 extern void jbd2_journal_update_sb_errno(journal_t *);
1432 extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t,
1433 unsigned long, int);
1434 extern void jbd2_journal_abort (journal_t *, int);
1435 extern int jbd2_journal_errno (journal_t *);
1436 extern void jbd2_journal_ack_err (journal_t *);
1437 extern int jbd2_journal_clear_err (journal_t *);
1438 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *);
1439 extern int jbd2_journal_force_commit(journal_t *);
1440 extern int jbd2_journal_force_commit_nested(journal_t *);
1441 extern int jbd2_journal_inode_ranged_write(handle_t *handle,
1442 struct jbd2_inode *inode, loff_t start_byte,
1444 extern int jbd2_journal_inode_ranged_wait(handle_t *handle,
1445 struct jbd2_inode *inode, loff_t start_byte,
1447 extern int jbd2_journal_submit_inode_data_buffers(
1448 struct jbd2_inode *jinode);
1449 extern int jbd2_journal_finish_inode_data_buffers(
1450 struct jbd2_inode *jinode);
1451 extern int jbd2_journal_begin_ordered_truncate(journal_t *journal,
1452 struct jbd2_inode *inode, loff_t new_size);
1453 extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode);
1454 extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode);
1457 * journal_head management
1459 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh);
1460 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh);
1461 void jbd2_journal_put_journal_head(struct journal_head *jh);
1466 extern struct kmem_cache *jbd2_handle_cache;
1468 static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags)
1470 return kmem_cache_zalloc(jbd2_handle_cache, gfp_flags);
1473 static inline void jbd2_free_handle(handle_t *handle)
1475 kmem_cache_free(jbd2_handle_cache, handle);
1479 * jbd2_inode management (optional, for those file systems that want to use
1480 * dynamically allocated jbd2_inode structures)
1482 extern struct kmem_cache *jbd2_inode_cache;
1484 static inline struct jbd2_inode *jbd2_alloc_inode(gfp_t gfp_flags)
1486 return kmem_cache_alloc(jbd2_inode_cache, gfp_flags);
1489 static inline void jbd2_free_inode(struct jbd2_inode *jinode)
1491 kmem_cache_free(jbd2_inode_cache, jinode);
1494 /* Primary revoke support */
1495 #define JOURNAL_REVOKE_DEFAULT_HASH 256
1496 extern int jbd2_journal_init_revoke(journal_t *, int);
1497 extern void jbd2_journal_destroy_revoke_record_cache(void);
1498 extern void jbd2_journal_destroy_revoke_table_cache(void);
1499 extern int __init jbd2_journal_init_revoke_record_cache(void);
1500 extern int __init jbd2_journal_init_revoke_table_cache(void);
1502 extern void jbd2_journal_destroy_revoke(journal_t *);
1503 extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *);
1504 extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *);
1505 extern void jbd2_journal_write_revoke_records(transaction_t *transaction,
1506 struct list_head *log_bufs);
1508 /* Recovery revoke support */
1509 extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t);
1510 extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t);
1511 extern void jbd2_journal_clear_revoke(journal_t *);
1512 extern void jbd2_journal_switch_revoke_table(journal_t *journal);
1513 extern void jbd2_clear_buffer_revoked_flags(journal_t *journal);
1516 * The log thread user interface:
1518 * Request space in the current transaction, and force transaction commit
1519 * transitions on demand.
1522 int jbd2_log_start_commit(journal_t *journal, tid_t tid);
1523 int __jbd2_log_start_commit(journal_t *journal, tid_t tid);
1524 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid);
1525 int jbd2_log_wait_commit(journal_t *journal, tid_t tid);
1526 int jbd2_transaction_committed(journal_t *journal, tid_t tid);
1527 int jbd2_complete_transaction(journal_t *journal, tid_t tid);
1528 int jbd2_log_do_checkpoint(journal_t *journal);
1529 int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid);
1531 void __jbd2_log_wait_for_space(journal_t *journal);
1532 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *);
1533 extern int jbd2_cleanup_journal_tail(journal_t *);
1538 * Simple test wrapper function to test the JBD2_ABORT state flag. This
1539 * bit, when set, indicates that we have had a fatal error somewhere,
1540 * either inside the journaling layer or indicated to us by the client
1541 * (eg. ext3), and that we and should not commit any further
1545 static inline int is_journal_aborted(journal_t *journal)
1547 return journal->j_flags & JBD2_ABORT;
1550 static inline int is_handle_aborted(handle_t *handle)
1552 if (handle->h_aborted || !handle->h_transaction)
1554 return is_journal_aborted(handle->h_transaction->t_journal);
1557 static inline void jbd2_journal_abort_handle(handle_t *handle)
1559 handle->h_aborted = 1;
1562 #endif /* __KERNEL__ */
1564 /* Comparison functions for transaction IDs: perform comparisons using
1565 * modulo arithmetic so that they work over sequence number wraps. */
1567 static inline int tid_gt(tid_t x, tid_t y)
1569 int difference = (x - y);
1570 return (difference > 0);
1573 static inline int tid_geq(tid_t x, tid_t y)
1575 int difference = (x - y);
1576 return (difference >= 0);
1579 extern int jbd2_journal_blocks_per_page(struct inode *inode);
1580 extern size_t journal_tag_bytes(journal_t *journal);
1582 static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j)
1584 return jbd2_has_feature_csum2(j) || jbd2_has_feature_csum3(j);
1587 static inline int jbd2_journal_has_csum_v2or3(journal_t *journal)
1589 WARN_ON_ONCE(jbd2_journal_has_csum_v2or3_feature(journal) &&
1590 journal->j_chksum_driver == NULL);
1592 return journal->j_chksum_driver != NULL;
1596 * Return number of free blocks in the log. Must be called under j_state_lock.
1598 static inline unsigned long jbd2_log_space_left(journal_t *journal)
1600 /* Allow for rounding errors */
1601 long free = journal->j_free - 32;
1603 if (journal->j_committing_transaction) {
1604 free -= atomic_read(&journal->
1605 j_committing_transaction->t_outstanding_credits);
1607 return max_t(long, free, 0);
1611 * Definitions which augment the buffer_head layer
1614 /* journaling buffer types */
1615 #define BJ_None 0 /* Not journaled */
1616 #define BJ_Metadata 1 /* Normal journaled metadata */
1617 #define BJ_Forget 2 /* Buffer superseded by this transaction */
1618 #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */
1619 #define BJ_Reserved 4 /* Buffer is reserved for access by journal */
1622 extern int jbd_blocks_per_page(struct inode *inode);
1624 /* JBD uses a CRC32 checksum */
1625 #define JBD_MAX_CHECKSUM_SIZE 4
1627 static inline u32 jbd2_chksum(journal_t *journal, u32 crc,
1628 const void *address, unsigned int length)
1631 struct shash_desc shash;
1632 char ctx[JBD_MAX_CHECKSUM_SIZE];
1636 BUG_ON(crypto_shash_descsize(journal->j_chksum_driver) >
1637 JBD_MAX_CHECKSUM_SIZE);
1639 desc.shash.tfm = journal->j_chksum_driver;
1640 *(u32 *)desc.ctx = crc;
1642 err = crypto_shash_update(&desc.shash, address, length);
1645 return *(u32 *)desc.ctx;
1648 /* Return most recent uncommitted transaction */
1649 static inline tid_t jbd2_get_latest_transaction(journal_t *journal)
1653 read_lock(&journal->j_state_lock);
1654 tid = journal->j_commit_request;
1655 if (journal->j_running_transaction)
1656 tid = journal->j_running_transaction->t_tid;
1657 read_unlock(&journal->j_state_lock);
1661 static inline int jbd2_handle_buffer_credits(handle_t *handle)
1665 if (!handle->h_reserved)
1666 journal = handle->h_transaction->t_journal;
1668 journal = handle->h_journal;
1670 return handle->h_total_credits -
1671 DIV_ROUND_UP(handle->h_revoke_credits_requested,
1672 journal->j_revoke_records_per_block);
1677 #define buffer_trace_init(bh) do {} while (0)
1678 #define print_buffer_fields(bh) do {} while (0)
1679 #define print_buffer_trace(bh) do {} while (0)
1680 #define BUFFER_TRACE(bh, info) do {} while (0)
1681 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0)
1682 #define JBUFFER_TRACE(jh, info) do {} while (0)
1684 #endif /* __KERNEL__ */
1686 #define EFSBADCRC EBADMSG /* Bad CRC detected */
1687 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
1689 #endif /* _LINUX_JBD2_H */