2 * linux/include/linux/jbd2.h
4 * Written by Stephen C. Tweedie <sct@redhat.com>
6 * Copyright 1998-2000 Red Hat, Inc --- All Rights Reserved
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.
12 * Definitions for transaction data structures for the buffer cache
13 * filesystem journaling support.
19 /* Allow this file to be included directly into e2fsprogs */
21 #include "jfs_compat.h"
25 #include <linux/types.h>
26 #include <linux/buffer_head.h>
27 #include <linux/journal-head.h>
28 #include <linux/stddef.h>
29 #include <linux/mutex.h>
30 #include <linux/timer.h>
31 #include <linux/slab.h>
32 #include <linux/bit_spinlock.h>
33 #include <crypto/hash.h>
36 #define journal_oom_retry 1
39 * Define JBD2_PARANIOD_IOFAIL to cause a kernel BUG() if ext4 finds
40 * certain classes of error which can occur due to failed IOs. Under
41 * normal use we want ext4 to continue after such errors, because
42 * hardware _can_ fail, but for debugging purposes when running tests on
43 * known-good hardware we may want to trap these errors.
45 #undef JBD2_PARANOID_IOFAIL
48 * The default maximum commit age, in seconds.
50 #define JBD2_DEFAULT_MAX_COMMIT_AGE 5
52 #ifdef CONFIG_JBD2_DEBUG
54 * Define JBD2_EXPENSIVE_CHECKING to enable more expensive internal
55 * consistency checks. By default we don't do this unless
56 * CONFIG_JBD2_DEBUG is on.
58 #define JBD2_EXPENSIVE_CHECKING
59 extern ushort jbd2_journal_enable_debug;
60 void __jbd2_debug(int level, const char *file, const char *func,
61 unsigned int line, const char *fmt, ...);
63 #define jbd_debug(n, fmt, a...) \
64 __jbd2_debug((n), __FILE__, __func__, __LINE__, (fmt), ##a)
66 #define jbd_debug(n, fmt, a...) /**/
69 extern void *jbd2_alloc(size_t size, gfp_t flags);
70 extern void jbd2_free(void *ptr, size_t size);
72 #define JBD2_MIN_JOURNAL_BLOCKS 1024
77 * typedef handle_t - The handle_t type represents a single atomic update being performed by some process.
79 * All filesystem modifications made by the process go
80 * through this handle. Recursive operations (such as quota operations)
81 * are gathered into a single update.
83 * The buffer credits field is used to account for journaled buffers
84 * being modified by the running process. To ensure that there is
85 * enough log space for all outstanding operations, we need to limit the
86 * number of outstanding buffers possible at any time. When the
87 * operation completes, any buffer credits not used are credited back to
88 * the transaction, so that at all times we know how many buffers the
89 * outstanding updates on a transaction might possibly touch.
91 * This is an opaque datatype.
93 typedef struct jbd2_journal_handle handle_t; /* Atomic operation type */
97 * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem.
99 * journal_t is linked to from the fs superblock structure.
101 * We use the journal_t to keep track of all outstanding transaction
102 * activity on the filesystem, and to manage the state of the log
105 * This is an opaque datatype.
107 typedef struct journal_s journal_t; /* Journal control structure */
111 * Internal structures used by the logging mechanism:
114 #define JBD2_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */
121 * Descriptor block types:
124 #define JBD2_DESCRIPTOR_BLOCK 1
125 #define JBD2_COMMIT_BLOCK 2
126 #define JBD2_SUPERBLOCK_V1 3
127 #define JBD2_SUPERBLOCK_V2 4
128 #define JBD2_REVOKE_BLOCK 5
131 * Standard header for all descriptor blocks:
133 typedef struct journal_header_s
143 #define JBD2_CRC32_CHKSUM 1
144 #define JBD2_MD5_CHKSUM 2
145 #define JBD2_SHA1_CHKSUM 3
146 #define JBD2_CRC32C_CHKSUM 4
148 #define JBD2_CRC32_CHKSUM_SIZE 4
150 #define JBD2_CHECKSUM_BYTES (32 / sizeof(u32))
152 * Commit block header for storing transactional checksums:
154 * NOTE: If FEATURE_COMPAT_CHECKSUM (checksum v1) is set, the h_chksum*
155 * fields are used to store a checksum of the descriptor and data blocks.
157 * If FEATURE_INCOMPAT_CSUM_V2 (checksum v2) is set, then the h_chksum
158 * field is used to store crc32c(uuid+commit_block). Each journal metadata
159 * block gets its own checksum, and data block checksums are stored in
160 * journal_block_tag (in the descriptor). The other h_chksum* fields are
163 * If FEATURE_INCOMPAT_CSUM_V3 is set, the descriptor block uses
164 * journal_block_tag3_t to store a full 32-bit checksum. Everything else
167 * Checksum v1, v2, and v3 are mutually exclusive features.
169 struct commit_header {
173 unsigned char h_chksum_type;
174 unsigned char h_chksum_size;
175 unsigned char h_padding[2];
176 __be32 h_chksum[JBD2_CHECKSUM_BYTES];
178 __be32 h_commit_nsec;
182 * The block tag: used to describe a single buffer in the journal.
183 * t_blocknr_high is only used if INCOMPAT_64BIT is set, so this
184 * raw struct shouldn't be used for pointer math or sizeof() - use
185 * journal_tag_bytes(journal) instead to compute this.
187 typedef struct journal_block_tag3_s
189 __be32 t_blocknr; /* The on-disk block number */
190 __be32 t_flags; /* See below */
191 __be32 t_blocknr_high; /* most-significant high 32bits. */
192 __be32 t_checksum; /* crc32c(uuid+seq+block) */
193 } journal_block_tag3_t;
195 typedef struct journal_block_tag_s
197 __be32 t_blocknr; /* The on-disk block number */
198 __be16 t_checksum; /* truncated crc32c(uuid+seq+block) */
199 __be16 t_flags; /* See below */
200 __be32 t_blocknr_high; /* most-significant high 32bits. */
201 } journal_block_tag_t;
203 /* Tail of descriptor block, for checksumming */
204 struct jbd2_journal_block_tail {
205 __be32 t_checksum; /* crc32c(uuid+descr_block) */
209 * The revoke descriptor: used on disk to describe a series of blocks to
210 * be revoked from the log
212 typedef struct jbd2_journal_revoke_header_s
214 journal_header_t r_header;
215 __be32 r_count; /* Count of bytes used in the block */
216 } jbd2_journal_revoke_header_t;
218 /* Tail of revoke block, for checksumming */
219 struct jbd2_journal_revoke_tail {
220 __be32 r_checksum; /* crc32c(uuid+revoke_block) */
223 /* Definitions for the journal tag flags word: */
224 #define JBD2_FLAG_ESCAPE 1 /* on-disk block is escaped */
225 #define JBD2_FLAG_SAME_UUID 2 /* block has same uuid as previous */
226 #define JBD2_FLAG_DELETED 4 /* block deleted by this transaction */
227 #define JBD2_FLAG_LAST_TAG 8 /* last tag in this descriptor block */
231 * The journal superblock. All fields are in big-endian byte order.
233 typedef struct journal_superblock_s
236 journal_header_t s_header;
239 /* Static information describing the journal */
240 __be32 s_blocksize; /* journal device blocksize */
241 __be32 s_maxlen; /* total blocks in journal file */
242 __be32 s_first; /* first block of log information */
245 /* Dynamic information describing the current state of the log */
246 __be32 s_sequence; /* first commit ID expected in log */
247 __be32 s_start; /* blocknr of start of log */
250 /* Error value, as set by jbd2_journal_abort(). */
254 /* Remaining fields are only valid in a version-2 superblock */
255 __be32 s_feature_compat; /* compatible feature set */
256 __be32 s_feature_incompat; /* incompatible feature set */
257 __be32 s_feature_ro_compat; /* readonly-compatible feature set */
259 __u8 s_uuid[16]; /* 128-bit uuid for journal */
262 __be32 s_nr_users; /* Nr of filesystems sharing log */
264 __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/
267 __be32 s_max_transaction; /* Limit of journal blocks per trans.*/
268 __be32 s_max_trans_data; /* Limit of data blocks per trans. */
271 __u8 s_checksum_type; /* checksum type */
274 __be32 s_checksum; /* crc32c(superblock) */
277 __u8 s_users[16*48]; /* ids of all fs'es sharing the log */
279 } journal_superblock_t;
281 /* Use the jbd2_{has,set,clear}_feature_* helpers; these will be removed */
282 #define JBD2_HAS_COMPAT_FEATURE(j,mask) \
283 ((j)->j_format_version >= 2 && \
284 ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask))))
285 #define JBD2_HAS_RO_COMPAT_FEATURE(j,mask) \
286 ((j)->j_format_version >= 2 && \
287 ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask))))
288 #define JBD2_HAS_INCOMPAT_FEATURE(j,mask) \
289 ((j)->j_format_version >= 2 && \
290 ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask))))
292 #define JBD2_FEATURE_COMPAT_CHECKSUM 0x00000001
294 #define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001
295 #define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002
296 #define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT 0x00000004
297 #define JBD2_FEATURE_INCOMPAT_CSUM_V2 0x00000008
298 #define JBD2_FEATURE_INCOMPAT_CSUM_V3 0x00000010
300 /* See "journal feature predicate functions" below */
302 /* Features known to this kernel version: */
303 #define JBD2_KNOWN_COMPAT_FEATURES JBD2_FEATURE_COMPAT_CHECKSUM
304 #define JBD2_KNOWN_ROCOMPAT_FEATURES 0
305 #define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \
306 JBD2_FEATURE_INCOMPAT_64BIT | \
307 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | \
308 JBD2_FEATURE_INCOMPAT_CSUM_V2 | \
309 JBD2_FEATURE_INCOMPAT_CSUM_V3)
313 #include <linux/fs.h>
314 #include <linux/sched.h>
316 enum jbd_state_bits {
317 BH_JBD /* Has an attached ext3 journal_head */
319 BH_JWrite, /* Being written to log (@@@ DEBUGGING) */
320 BH_Freed, /* Has been freed (truncated) */
321 BH_Revoked, /* Has been revoked from the log */
322 BH_RevokeValid, /* Revoked flag is valid */
323 BH_JBDDirty, /* Is dirty but journaled */
324 BH_State, /* Pins most journal_head state */
325 BH_JournalHead, /* Pins bh->b_private and jh->b_bh */
326 BH_Shadow, /* IO on shadow buffer is running */
327 BH_Verified, /* Metadata block has been verified ok */
328 BH_JBDPrivateStart, /* First bit available for private use by FS */
332 BUFFER_FNS(JWrite, jwrite)
333 BUFFER_FNS(JBDDirty, jbddirty)
334 TAS_BUFFER_FNS(JBDDirty, jbddirty)
335 BUFFER_FNS(Revoked, revoked)
336 TAS_BUFFER_FNS(Revoked, revoked)
337 BUFFER_FNS(RevokeValid, revokevalid)
338 TAS_BUFFER_FNS(RevokeValid, revokevalid)
339 BUFFER_FNS(Freed, freed)
340 BUFFER_FNS(Shadow, shadow)
341 BUFFER_FNS(Verified, verified)
343 static inline struct buffer_head *jh2bh(struct journal_head *jh)
348 static inline struct journal_head *bh2jh(struct buffer_head *bh)
350 return bh->b_private;
353 static inline void jbd_lock_bh_state(struct buffer_head *bh)
355 bit_spin_lock(BH_State, &bh->b_state);
358 static inline int jbd_trylock_bh_state(struct buffer_head *bh)
360 return bit_spin_trylock(BH_State, &bh->b_state);
363 static inline int jbd_is_locked_bh_state(struct buffer_head *bh)
365 return bit_spin_is_locked(BH_State, &bh->b_state);
368 static inline void jbd_unlock_bh_state(struct buffer_head *bh)
370 bit_spin_unlock(BH_State, &bh->b_state);
373 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh)
375 bit_spin_lock(BH_JournalHead, &bh->b_state);
378 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
380 bit_spin_unlock(BH_JournalHead, &bh->b_state);
383 #define J_ASSERT(assert) BUG_ON(!(assert))
385 #define J_ASSERT_BH(bh, expr) J_ASSERT(expr)
386 #define J_ASSERT_JH(jh, expr) J_ASSERT(expr)
388 #if defined(JBD2_PARANOID_IOFAIL)
389 #define J_EXPECT(expr, why...) J_ASSERT(expr)
390 #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr)
391 #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr)
393 #define __journal_expect(expr, why...) \
398 "JBD2 unexpected failure: %s: %s;\n", \
400 printk(KERN_ERR why "\n"); \
404 #define J_EXPECT(expr, why...) __journal_expect(expr, ## why)
405 #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why)
406 #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why)
409 /* Flags in jbd_inode->i_flags */
410 #define __JI_COMMIT_RUNNING 0
411 /* Commit of the inode data in progress. We use this flag to protect us from
412 * concurrent deletion of inode. We cannot use reference to inode for this
413 * since we cannot afford doing last iput() on behalf of kjournald
415 #define JI_COMMIT_RUNNING (1 << __JI_COMMIT_RUNNING)
418 * struct jbd_inode is the structure linking inodes in ordered mode
419 * present in a transaction so that we can sync them during commit.
422 /* Which transaction does this inode belong to? Either the running
423 * transaction or the committing one. [j_list_lock] */
424 transaction_t *i_transaction;
426 /* Pointer to the running transaction modifying inode's data in case
427 * there is already a committing transaction touching it. [j_list_lock] */
428 transaction_t *i_next_transaction;
430 /* List of inodes in the i_transaction [j_list_lock] */
431 struct list_head i_list;
433 /* VFS inode this inode belongs to [constant during the lifetime
434 * of the structure] */
435 struct inode *i_vfs_inode;
437 /* Flags of inode [j_list_lock] */
438 unsigned long i_flags;
441 struct jbd2_revoke_table_s;
444 * struct handle_s - The handle_s type is the concrete type associated with
446 * @h_transaction: Which compound transaction is this update a part of?
447 * @h_buffer_credits: Number of remaining buffers we are allowed to dirty.
448 * @h_ref: Reference count on this handle
449 * @h_err: Field for caller's use to track errors through large fs operations
450 * @h_sync: flag for sync-on-close
451 * @h_jdata: flag to force data journaling
452 * @h_aborted: flag indicating fatal error on handle
455 /* Docbook can't yet cope with the bit fields, but will leave the documentation
456 * in so it can be fixed later.
459 struct jbd2_journal_handle
462 /* Which compound transaction is this update a part of? */
463 transaction_t *h_transaction;
464 /* Which journal handle belongs to - used iff h_reserved set */
465 journal_t *h_journal;
468 /* Handle reserved for finishing the logical operation */
469 handle_t *h_rsv_handle;
471 /* Number of remaining buffers we are allowed to dirty: */
472 int h_buffer_credits;
474 /* Reference count on this handle */
477 /* Field for caller's use to track errors through large fs */
481 /* Flags [no locking] */
482 unsigned int h_sync: 1; /* sync-on-close */
483 unsigned int h_jdata: 1; /* force data journaling */
484 unsigned int h_reserved: 1; /* handle with reserved credits */
485 unsigned int h_aborted: 1; /* fatal error on handle */
486 unsigned int h_type: 8; /* for handle statistics */
487 unsigned int h_line_no: 16; /* for handle statistics */
489 unsigned long h_start_jiffies;
490 unsigned int h_requested_credits;
492 #ifdef CONFIG_DEBUG_LOCK_ALLOC
493 struct lockdep_map h_lockdep_map;
499 * Some stats for checkpoint phase
501 struct transaction_chp_stats_s {
502 unsigned long cs_chp_time;
503 __u32 cs_forced_to_close;
508 /* The transaction_t type is the guts of the journaling mechanism. It
509 * tracks a compound transaction through its various states:
511 * RUNNING: accepting new updates
512 * LOCKED: Updates still running but we don't accept new ones
513 * RUNDOWN: Updates are tidying up but have finished requesting
514 * new buffers to modify (state not used for now)
515 * FLUSH: All updates complete, but we are still writing to disk
516 * COMMIT: All data on disk, writing commit record
517 * FINISHED: We still have to keep the transaction for checkpointing.
519 * The transaction keeps track of all of the buffers modified by a
520 * running transaction, and all of the buffers committed but not yet
521 * flushed to home for finished transactions.
528 * ->jbd_lock_bh_journal_head() (This is "innermost")
531 * ->jbd_lock_bh_state()
533 * jbd_lock_bh_state()
540 * ->j_list_lock (journal_unmap_buffer)
546 /* Pointer to the journal for this transaction. [no locking] */
547 journal_t *t_journal;
549 /* Sequence number for this transaction [no locking] */
553 * Transaction's current state
554 * [no locking - only kjournald2 alters this]
555 * [j_list_lock] guards transition of a transaction into T_FINISHED
556 * state and subsequent call of __jbd2_journal_drop_transaction()
557 * FIXME: needs barriers
558 * KLUDGE: [use j_state_lock]
572 * Where in the log does this transaction's commit start? [no locking]
574 unsigned long t_log_start;
576 /* Number of buffers on the t_buffers list [j_list_lock] */
580 * Doubly-linked circular list of all buffers reserved but not yet
581 * modified by this transaction [j_list_lock]
583 struct journal_head *t_reserved_list;
586 * Doubly-linked circular list of all metadata buffers owned by this
587 * transaction [j_list_lock]
589 struct journal_head *t_buffers;
592 * Doubly-linked circular list of all forget buffers (superseded
593 * buffers which we can un-checkpoint once this transaction commits)
596 struct journal_head *t_forget;
599 * Doubly-linked circular list of all buffers still to be flushed before
600 * this transaction can be checkpointed. [j_list_lock]
602 struct journal_head *t_checkpoint_list;
605 * Doubly-linked circular list of all buffers submitted for IO while
606 * checkpointing. [j_list_lock]
608 struct journal_head *t_checkpoint_io_list;
611 * Doubly-linked circular list of metadata buffers being shadowed by log
612 * IO. The IO buffers on the iobuf list and the shadow buffers on this
613 * list match each other one for one at all times. [j_list_lock]
615 struct journal_head *t_shadow_list;
618 * List of inodes whose data we've modified in data=ordered mode.
621 struct list_head t_inode_list;
624 * Protects info related to handles
626 spinlock_t t_handle_lock;
629 * Longest time some handle had to wait for running transaction
631 unsigned long t_max_wait;
634 * When transaction started
636 unsigned long t_start;
639 * When commit was requested
641 unsigned long t_requested;
644 * Checkpointing stats [j_checkpoint_sem]
646 struct transaction_chp_stats_s t_chp_stats;
649 * Number of outstanding updates running on this transaction
655 * Number of buffers reserved for use by all handles in this transaction
656 * handle but not yet modified. [t_handle_lock]
658 atomic_t t_outstanding_credits;
661 * Forward and backward links for the circular list of all transactions
662 * awaiting checkpoint. [j_list_lock]
664 transaction_t *t_cpnext, *t_cpprev;
667 * When will the transaction expire (become due for commit), in jiffies?
670 unsigned long t_expires;
673 * When this transaction started, in nanoseconds [no locking]
675 ktime_t t_start_time;
678 * How many handles used this transaction? [t_handle_lock]
680 atomic_t t_handle_count;
683 * This transaction is being forced and some process is
684 * waiting for it to finish.
686 unsigned int t_synchronous_commit:1;
688 /* Disk flush needs to be sent to fs partition [no locking] */
689 int t_need_data_flush;
692 * For use by the filesystem to store fs-specific data
693 * structures associated with the transaction
695 struct list_head t_private_list;
698 struct transaction_run_stats_s {
699 unsigned long rs_wait;
700 unsigned long rs_request_delay;
701 unsigned long rs_running;
702 unsigned long rs_locked;
703 unsigned long rs_flushing;
704 unsigned long rs_logging;
706 __u32 rs_handle_count;
708 __u32 rs_blocks_logged;
711 struct transaction_stats_s {
712 unsigned long ts_tid;
713 unsigned long ts_requested;
714 struct transaction_run_stats_s run;
717 static inline unsigned long
718 jbd2_time_diff(unsigned long start, unsigned long end)
723 return end + (MAX_JIFFY_OFFSET - start);
726 #define JBD2_NR_BATCH 64
729 * struct journal_s - The journal_s type is the concrete type associated with
731 * @j_flags: General journaling state flags
732 * @j_errno: Is there an outstanding uncleared error on the journal (from a
734 * @j_sb_buffer: First part of superblock buffer
735 * @j_superblock: Second part of superblock buffer
736 * @j_format_version: Version of the superblock format
737 * @j_state_lock: Protect the various scalars in the journal
738 * @j_barrier_count: Number of processes waiting to create a barrier lock
739 * @j_barrier: The barrier lock itself
740 * @j_running_transaction: The current running transaction..
741 * @j_committing_transaction: the transaction we are pushing to disk
742 * @j_checkpoint_transactions: a linked circular list of all transactions
743 * waiting for checkpointing
744 * @j_wait_transaction_locked: Wait queue for waiting for a locked transaction
745 * to start committing, or for a barrier lock to be released
746 * @j_wait_done_commit: Wait queue for waiting for commit to complete
747 * @j_wait_commit: Wait queue to trigger commit
748 * @j_wait_updates: Wait queue to wait for updates to complete
749 * @j_wait_reserved: Wait queue to wait for reserved buffer credits to drop
750 * @j_checkpoint_mutex: Mutex for locking against concurrent checkpoints
751 * @j_head: Journal head - identifies the first unused block in the journal
752 * @j_tail: Journal tail - identifies the oldest still-used block in the
754 * @j_free: Journal free - how many free blocks are there in the journal?
755 * @j_first: The block number of the first usable block
756 * @j_last: The block number one beyond the last usable block
757 * @j_dev: Device where we store the journal
758 * @j_blocksize: blocksize for the location where we store the journal.
759 * @j_blk_offset: starting block offset for into the device where we store the
761 * @j_fs_dev: Device which holds the client fs. For internal journal this will
763 * @j_reserved_credits: Number of buffers reserved from the running transaction
764 * @j_maxlen: Total maximum capacity of the journal region on disk.
765 * @j_list_lock: Protects the buffer lists and internal buffer state.
766 * @j_inode: Optional inode where we store the journal. If present, all journal
767 * block numbers are mapped into this inode via bmap().
768 * @j_tail_sequence: Sequence number of the oldest transaction in the log
769 * @j_transaction_sequence: Sequence number of the next transaction to grant
770 * @j_commit_sequence: Sequence number of the most recently committed
772 * @j_commit_request: Sequence number of the most recent transaction wanting
774 * @j_uuid: Uuid of client object.
775 * @j_task: Pointer to the current commit thread for this journal
776 * @j_max_transaction_buffers: Maximum number of metadata buffers to allow in a
777 * single compound commit transaction
778 * @j_commit_interval: What is the maximum transaction lifetime before we begin
780 * @j_commit_timer: The timer used to wakeup the commit thread
781 * @j_revoke_lock: Protect the revoke table
782 * @j_revoke: The revoke table - maintains the list of revoked blocks in the
783 * current transaction.
784 * @j_revoke_table: alternate revoke tables for j_revoke
785 * @j_wbuf: array of buffer_heads for jbd2_journal_commit_transaction
786 * @j_wbufsize: maximum number of buffer_heads allowed in j_wbuf, the
787 * number that will fit in j_blocksize
788 * @j_last_sync_writer: most recent pid which did a synchronous write
789 * @j_history: Buffer storing the transactions statistics history
790 * @j_history_max: Maximum number of transactions in the statistics history
791 * @j_history_cur: Current number of transactions in the statistics history
792 * @j_history_lock: Protect the transactions statistics history
793 * @j_proc_entry: procfs entry for the jbd statistics directory
794 * @j_stats: Overall statistics
795 * @j_private: An opaque pointer to fs-private information.
800 /* General journaling state flags [j_state_lock] */
801 unsigned long j_flags;
804 * Is there an outstanding uncleared error on the journal (from a prior
805 * abort)? [j_state_lock]
809 /* The superblock buffer */
810 struct buffer_head *j_sb_buffer;
811 journal_superblock_t *j_superblock;
813 /* Version of the superblock format */
814 int j_format_version;
817 * Protect the various scalars in the journal
819 rwlock_t j_state_lock;
822 * Number of processes waiting to create a barrier lock [j_state_lock]
826 /* The barrier lock itself */
827 struct mutex j_barrier;
830 * Transactions: The current running transaction...
831 * [j_state_lock] [caller holding open handle]
833 transaction_t *j_running_transaction;
836 * the transaction we are pushing to disk
837 * [j_state_lock] [caller holding open handle]
839 transaction_t *j_committing_transaction;
842 * ... and a linked circular list of all transactions waiting for
843 * checkpointing. [j_list_lock]
845 transaction_t *j_checkpoint_transactions;
848 * Wait queue for waiting for a locked transaction to start committing,
849 * or for a barrier lock to be released
851 wait_queue_head_t j_wait_transaction_locked;
853 /* Wait queue for waiting for commit to complete */
854 wait_queue_head_t j_wait_done_commit;
856 /* Wait queue to trigger commit */
857 wait_queue_head_t j_wait_commit;
859 /* Wait queue to wait for updates to complete */
860 wait_queue_head_t j_wait_updates;
862 /* Wait queue to wait for reserved buffer credits to drop */
863 wait_queue_head_t j_wait_reserved;
865 /* Semaphore for locking against concurrent checkpoints */
866 struct mutex j_checkpoint_mutex;
869 * List of buffer heads used by the checkpoint routine. This
870 * was moved from jbd2_log_do_checkpoint() to reduce stack
871 * usage. Access to this array is controlled by the
872 * j_checkpoint_mutex. [j_checkpoint_mutex]
874 struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH];
877 * Journal head: identifies the first unused block in the journal.
880 unsigned long j_head;
883 * Journal tail: identifies the oldest still-used block in the journal.
886 unsigned long j_tail;
889 * Journal free: how many free blocks are there in the journal?
892 unsigned long j_free;
895 * Journal start and end: the block numbers of the first usable block
896 * and one beyond the last usable block in the journal. [j_state_lock]
898 unsigned long j_first;
899 unsigned long j_last;
902 * Device, blocksize and starting block offset for the location where we
905 struct block_device *j_dev;
907 unsigned long long j_blk_offset;
908 char j_devname[BDEVNAME_SIZE+24];
911 * Device which holds the client fs. For internal journal this will be
914 struct block_device *j_fs_dev;
916 /* Total maximum capacity of the journal region on disk. */
917 unsigned int j_maxlen;
919 /* Number of buffers reserved from the running transaction */
920 atomic_t j_reserved_credits;
923 * Protects the buffer lists and internal buffer state.
925 spinlock_t j_list_lock;
927 /* Optional inode where we store the journal. If present, all */
928 /* journal block numbers are mapped into this inode via */
930 struct inode *j_inode;
933 * Sequence number of the oldest transaction in the log [j_state_lock]
935 tid_t j_tail_sequence;
938 * Sequence number of the next transaction to grant [j_state_lock]
940 tid_t j_transaction_sequence;
943 * Sequence number of the most recently committed transaction
946 tid_t j_commit_sequence;
949 * Sequence number of the most recent transaction wanting commit
952 tid_t j_commit_request;
955 * Journal uuid: identifies the object (filesystem, LVM volume etc)
956 * backed by this journal. This will eventually be replaced by an array
957 * of uuids, allowing us to index multiple devices within a single
958 * journal and to perform atomic updates across them.
962 /* Pointer to the current commit thread for this journal */
963 struct task_struct *j_task;
966 * Maximum number of metadata buffers to allow in a single compound
969 int j_max_transaction_buffers;
972 * What is the maximum transaction lifetime before we begin a commit?
974 unsigned long j_commit_interval;
976 /* The timer used to wakeup the commit thread: */
977 struct timer_list j_commit_timer;
980 * The revoke table: maintains the list of revoked blocks in the
981 * current transaction. [j_revoke_lock]
983 spinlock_t j_revoke_lock;
984 struct jbd2_revoke_table_s *j_revoke;
985 struct jbd2_revoke_table_s *j_revoke_table[2];
988 * array of bhs for jbd2_journal_commit_transaction
990 struct buffer_head **j_wbuf;
994 * this is the pid of hte last person to run a synchronous operation
995 * through the journal
997 pid_t j_last_sync_writer;
1000 * the average amount of time in nanoseconds it takes to commit a
1001 * transaction to disk. [j_state_lock]
1003 u64 j_average_commit_time;
1006 * minimum and maximum times that we should wait for
1007 * additional filesystem operations to get batched into a
1008 * synchronous handle in microseconds
1010 u32 j_min_batch_time;
1011 u32 j_max_batch_time;
1013 /* This function is called when a transaction is closed */
1014 void (*j_commit_callback)(journal_t *,
1018 * Journal statistics
1020 spinlock_t j_history_lock;
1021 struct proc_dir_entry *j_proc_entry;
1022 struct transaction_stats_s j_stats;
1024 /* Failed journal commit ID */
1025 unsigned int j_failed_commit;
1028 * An opaque pointer to fs-private information. ext3 puts its
1029 * superblock pointer here
1033 /* Reference to checksum algorithm driver via cryptoapi */
1034 struct crypto_shash *j_chksum_driver;
1036 /* Precomputed journal UUID checksum for seeding other checksums */
1040 /* journal feature predicate functions */
1041 #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \
1042 static inline bool jbd2_has_feature_##name(journal_t *j) \
1044 return ((j)->j_format_version >= 2 && \
1045 ((j)->j_superblock->s_feature_compat & \
1046 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \
1048 static inline void jbd2_set_feature_##name(journal_t *j) \
1050 (j)->j_superblock->s_feature_compat |= \
1051 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \
1053 static inline void jbd2_clear_feature_##name(journal_t *j) \
1055 (j)->j_superblock->s_feature_compat &= \
1056 ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \
1059 #define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1060 static inline bool jbd2_has_feature_##name(journal_t *j) \
1062 return ((j)->j_format_version >= 2 && \
1063 ((j)->j_superblock->s_feature_ro_compat & \
1064 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \
1066 static inline void jbd2_set_feature_##name(journal_t *j) \
1068 (j)->j_superblock->s_feature_ro_compat |= \
1069 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \
1071 static inline void jbd2_clear_feature_##name(journal_t *j) \
1073 (j)->j_superblock->s_feature_ro_compat &= \
1074 ~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \
1077 #define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1078 static inline bool jbd2_has_feature_##name(journal_t *j) \
1080 return ((j)->j_format_version >= 2 && \
1081 ((j)->j_superblock->s_feature_incompat & \
1082 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \
1084 static inline void jbd2_set_feature_##name(journal_t *j) \
1086 (j)->j_superblock->s_feature_incompat |= \
1087 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \
1089 static inline void jbd2_clear_feature_##name(journal_t *j) \
1091 (j)->j_superblock->s_feature_incompat &= \
1092 ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \
1095 JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM)
1097 JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE)
1098 JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT)
1099 JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT)
1100 JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2)
1101 JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3)
1104 * Journal flag definitions
1106 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */
1107 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */
1108 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */
1109 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */
1110 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */
1111 #define JBD2_BARRIER 0x020 /* Use IDE barriers */
1112 #define JBD2_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file
1113 * data write error in ordered
1115 #define JBD2_REC_ERR 0x080 /* The errno in the sb has been recorded */
1118 * Function declarations for the journaling transaction and buffer
1122 /* Filing buffers */
1123 extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *);
1124 extern void __jbd2_journal_refile_buffer(struct journal_head *);
1125 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *);
1126 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
1127 extern void __journal_free_buffer(struct journal_head *bh);
1128 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
1129 extern void __journal_clean_data_list(transaction_t *transaction);
1130 static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh)
1132 list_add_tail(&bh->b_assoc_buffers, head);
1134 static inline void jbd2_unfile_log_bh(struct buffer_head *bh)
1136 list_del_init(&bh->b_assoc_buffers);
1139 /* Log buffer allocation */
1140 struct buffer_head *jbd2_journal_get_descriptor_buffer(journal_t *journal);
1141 int jbd2_journal_next_log_block(journal_t *, unsigned long long *);
1142 int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid,
1143 unsigned long *block);
1144 int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block);
1145 void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block);
1147 /* Commit management */
1148 extern void jbd2_journal_commit_transaction(journal_t *);
1150 /* Checkpoint list management */
1151 void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy);
1152 int __jbd2_journal_remove_checkpoint(struct journal_head *);
1153 void jbd2_journal_destroy_checkpoint(journal_t *journal);
1154 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *);
1161 struct jbd2_buffer_trigger_type {
1163 * Fired a the moment data to write to the journal are known to be
1164 * stable - so either at the moment b_frozen_data is created or just
1165 * before a buffer is written to the journal. mapped_data is a mapped
1166 * buffer that is the frozen data for commit.
1168 void (*t_frozen)(struct jbd2_buffer_trigger_type *type,
1169 struct buffer_head *bh, void *mapped_data,
1173 * Fired during journal abort for dirty buffers that will not be
1176 void (*t_abort)(struct jbd2_buffer_trigger_type *type,
1177 struct buffer_head *bh);
1180 extern void jbd2_buffer_frozen_trigger(struct journal_head *jh,
1182 struct jbd2_buffer_trigger_type *triggers);
1183 extern void jbd2_buffer_abort_trigger(struct journal_head *jh,
1184 struct jbd2_buffer_trigger_type *triggers);
1187 extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
1188 struct journal_head *jh_in,
1189 struct buffer_head **bh_out,
1192 /* Transaction locking */
1193 extern void __wait_on_journal (journal_t *);
1195 /* Transaction cache support */
1196 extern void jbd2_journal_destroy_transaction_cache(void);
1197 extern int jbd2_journal_init_transaction_cache(void);
1198 extern void jbd2_journal_free_transaction(transaction_t *);
1203 * We need to lock the journal during transaction state changes so that nobody
1204 * ever tries to take a handle on the running transaction while we are in the
1205 * middle of moving it to the commit phase. j_state_lock does this.
1207 * Note that the locking is completely interrupt unsafe. We never touch
1208 * journal structures from interrupts.
1211 static inline handle_t *journal_current_handle(void)
1213 return current->journal_info;
1216 /* The journaling code user interface:
1218 * Create and destroy handles
1219 * Register buffer modifications against the current transaction.
1222 extern handle_t *jbd2_journal_start(journal_t *, int nblocks);
1223 extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks,
1224 gfp_t gfp_mask, unsigned int type,
1225 unsigned int line_no);
1226 extern int jbd2_journal_restart(handle_t *, int nblocks);
1227 extern int jbd2__journal_restart(handle_t *, int nblocks, gfp_t gfp_mask);
1228 extern int jbd2_journal_start_reserved(handle_t *handle,
1229 unsigned int type, unsigned int line_no);
1230 extern void jbd2_journal_free_reserved(handle_t *handle);
1231 extern int jbd2_journal_extend (handle_t *, int nblocks);
1232 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *);
1233 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *);
1234 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *);
1235 void jbd2_journal_set_triggers(struct buffer_head *,
1236 struct jbd2_buffer_trigger_type *type);
1237 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *);
1238 extern int jbd2_journal_forget (handle_t *, struct buffer_head *);
1239 extern void journal_sync_buffer (struct buffer_head *);
1240 extern int jbd2_journal_invalidatepage(journal_t *,
1241 struct page *, unsigned int, unsigned int);
1242 extern int jbd2_journal_try_to_free_buffers(journal_t *, struct page *, gfp_t);
1243 extern int jbd2_journal_stop(handle_t *);
1244 extern int jbd2_journal_flush (journal_t *);
1245 extern void jbd2_journal_lock_updates (journal_t *);
1246 extern void jbd2_journal_unlock_updates (journal_t *);
1248 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev,
1249 struct block_device *fs_dev,
1250 unsigned long long start, int len, int bsize);
1251 extern journal_t * jbd2_journal_init_inode (struct inode *);
1252 extern int jbd2_journal_update_format (journal_t *);
1253 extern int jbd2_journal_check_used_features
1254 (journal_t *, unsigned long, unsigned long, unsigned long);
1255 extern int jbd2_journal_check_available_features
1256 (journal_t *, unsigned long, unsigned long, unsigned long);
1257 extern int jbd2_journal_set_features
1258 (journal_t *, unsigned long, unsigned long, unsigned long);
1259 extern void jbd2_journal_clear_features
1260 (journal_t *, unsigned long, unsigned long, unsigned long);
1261 extern int jbd2_journal_load (journal_t *journal);
1262 extern int jbd2_journal_destroy (journal_t *);
1263 extern int jbd2_journal_recover (journal_t *journal);
1264 extern int jbd2_journal_wipe (journal_t *, int);
1265 extern int jbd2_journal_skip_recovery (journal_t *);
1266 extern void jbd2_journal_update_sb_errno(journal_t *);
1267 extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t,
1268 unsigned long, int);
1269 extern void __jbd2_journal_abort_hard (journal_t *);
1270 extern void jbd2_journal_abort (journal_t *, int);
1271 extern int jbd2_journal_errno (journal_t *);
1272 extern void jbd2_journal_ack_err (journal_t *);
1273 extern int jbd2_journal_clear_err (journal_t *);
1274 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *);
1275 extern int jbd2_journal_force_commit(journal_t *);
1276 extern int jbd2_journal_force_commit_nested(journal_t *);
1277 extern int jbd2_journal_file_inode(handle_t *handle, struct jbd2_inode *inode);
1278 extern int jbd2_journal_begin_ordered_truncate(journal_t *journal,
1279 struct jbd2_inode *inode, loff_t new_size);
1280 extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode);
1281 extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode);
1284 * journal_head management
1286 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh);
1287 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh);
1288 void jbd2_journal_put_journal_head(struct journal_head *jh);
1293 extern struct kmem_cache *jbd2_handle_cache;
1295 static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags)
1297 return kmem_cache_zalloc(jbd2_handle_cache, gfp_flags);
1300 static inline void jbd2_free_handle(handle_t *handle)
1302 kmem_cache_free(jbd2_handle_cache, handle);
1306 * jbd2_inode management (optional, for those file systems that want to use
1307 * dynamically allocated jbd2_inode structures)
1309 extern struct kmem_cache *jbd2_inode_cache;
1311 static inline struct jbd2_inode *jbd2_alloc_inode(gfp_t gfp_flags)
1313 return kmem_cache_alloc(jbd2_inode_cache, gfp_flags);
1316 static inline void jbd2_free_inode(struct jbd2_inode *jinode)
1318 kmem_cache_free(jbd2_inode_cache, jinode);
1321 /* Primary revoke support */
1322 #define JOURNAL_REVOKE_DEFAULT_HASH 256
1323 extern int jbd2_journal_init_revoke(journal_t *, int);
1324 extern void jbd2_journal_destroy_revoke_caches(void);
1325 extern int jbd2_journal_init_revoke_caches(void);
1327 extern void jbd2_journal_destroy_revoke(journal_t *);
1328 extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *);
1329 extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *);
1330 extern void jbd2_journal_write_revoke_records(journal_t *journal,
1331 transaction_t *transaction,
1332 struct list_head *log_bufs,
1335 /* Recovery revoke support */
1336 extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t);
1337 extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t);
1338 extern void jbd2_journal_clear_revoke(journal_t *);
1339 extern void jbd2_journal_switch_revoke_table(journal_t *journal);
1340 extern void jbd2_clear_buffer_revoked_flags(journal_t *journal);
1343 * The log thread user interface:
1345 * Request space in the current transaction, and force transaction commit
1346 * transitions on demand.
1349 int jbd2_log_start_commit(journal_t *journal, tid_t tid);
1350 int __jbd2_log_start_commit(journal_t *journal, tid_t tid);
1351 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid);
1352 int jbd2_log_wait_commit(journal_t *journal, tid_t tid);
1353 int jbd2_complete_transaction(journal_t *journal, tid_t tid);
1354 int jbd2_log_do_checkpoint(journal_t *journal);
1355 int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid);
1357 void __jbd2_log_wait_for_space(journal_t *journal);
1358 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *);
1359 extern int jbd2_cleanup_journal_tail(journal_t *);
1364 * Simple test wrapper function to test the JBD2_ABORT state flag. This
1365 * bit, when set, indicates that we have had a fatal error somewhere,
1366 * either inside the journaling layer or indicated to us by the client
1367 * (eg. ext3), and that we and should not commit any further
1371 static inline int is_journal_aborted(journal_t *journal)
1373 return journal->j_flags & JBD2_ABORT;
1376 static inline int is_handle_aborted(handle_t *handle)
1378 if (handle->h_aborted || !handle->h_transaction)
1380 return is_journal_aborted(handle->h_transaction->t_journal);
1383 static inline void jbd2_journal_abort_handle(handle_t *handle)
1385 handle->h_aborted = 1;
1388 #endif /* __KERNEL__ */
1390 /* Comparison functions for transaction IDs: perform comparisons using
1391 * modulo arithmetic so that they work over sequence number wraps. */
1393 static inline int tid_gt(tid_t x, tid_t y)
1395 int difference = (x - y);
1396 return (difference > 0);
1399 static inline int tid_geq(tid_t x, tid_t y)
1401 int difference = (x - y);
1402 return (difference >= 0);
1405 extern int jbd2_journal_blocks_per_page(struct inode *inode);
1406 extern size_t journal_tag_bytes(journal_t *journal);
1408 static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j)
1410 return jbd2_has_feature_csum2(j) || jbd2_has_feature_csum3(j);
1413 static inline int jbd2_journal_has_csum_v2or3(journal_t *journal)
1415 WARN_ON_ONCE(jbd2_journal_has_csum_v2or3_feature(journal) &&
1416 journal->j_chksum_driver == NULL);
1418 return journal->j_chksum_driver != NULL;
1422 * We reserve t_outstanding_credits >> JBD2_CONTROL_BLOCKS_SHIFT for
1423 * transaction control blocks.
1425 #define JBD2_CONTROL_BLOCKS_SHIFT 5
1428 * Return the minimum number of blocks which must be free in the journal
1429 * before a new transaction may be started. Must be called under j_state_lock.
1431 static inline int jbd2_space_needed(journal_t *journal)
1433 int nblocks = journal->j_max_transaction_buffers;
1434 return nblocks + (nblocks >> JBD2_CONTROL_BLOCKS_SHIFT);
1438 * Return number of free blocks in the log. Must be called under j_state_lock.
1440 static inline unsigned long jbd2_log_space_left(journal_t *journal)
1442 /* Allow for rounding errors */
1443 unsigned long free = journal->j_free - 32;
1445 if (journal->j_committing_transaction) {
1446 unsigned long committing = atomic_read(&journal->
1447 j_committing_transaction->t_outstanding_credits);
1449 /* Transaction + control blocks */
1450 free -= committing + (committing >> JBD2_CONTROL_BLOCKS_SHIFT);
1456 * Definitions which augment the buffer_head layer
1459 /* journaling buffer types */
1460 #define BJ_None 0 /* Not journaled */
1461 #define BJ_Metadata 1 /* Normal journaled metadata */
1462 #define BJ_Forget 2 /* Buffer superseded by this transaction */
1463 #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */
1464 #define BJ_Reserved 4 /* Buffer is reserved for access by journal */
1467 extern int jbd_blocks_per_page(struct inode *inode);
1469 /* JBD uses a CRC32 checksum */
1470 #define JBD_MAX_CHECKSUM_SIZE 4
1472 static inline u32 jbd2_chksum(journal_t *journal, u32 crc,
1473 const void *address, unsigned int length)
1476 struct shash_desc shash;
1477 char ctx[JBD_MAX_CHECKSUM_SIZE];
1481 BUG_ON(crypto_shash_descsize(journal->j_chksum_driver) >
1482 JBD_MAX_CHECKSUM_SIZE);
1484 desc.shash.tfm = journal->j_chksum_driver;
1485 desc.shash.flags = 0;
1486 *(u32 *)desc.ctx = crc;
1488 err = crypto_shash_update(&desc.shash, address, length);
1491 return *(u32 *)desc.ctx;
1494 /* Return most recent uncommitted transaction */
1495 static inline tid_t jbd2_get_latest_transaction(journal_t *journal)
1499 read_lock(&journal->j_state_lock);
1500 tid = journal->j_commit_request;
1501 if (journal->j_running_transaction)
1502 tid = journal->j_running_transaction->t_tid;
1503 read_unlock(&journal->j_state_lock);
1509 #define buffer_trace_init(bh) do {} while (0)
1510 #define print_buffer_fields(bh) do {} while (0)
1511 #define print_buffer_trace(bh) do {} while (0)
1512 #define BUFFER_TRACE(bh, info) do {} while (0)
1513 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0)
1514 #define JBUFFER_TRACE(jh, info) do {} while (0)
1516 #endif /* __KERNEL__ */
1518 #define EFSBADCRC EBADMSG /* Bad CRC detected */
1519 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
1521 #endif /* _LINUX_JBD2_H */