linux/include/linux/jbd2.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * linux/include/linux/jbd2.h
 *
 * Written by Stephen C. Tweedie <[email protected]>
 *
 * Copyright 1998-2000 Red Hat, Inc --- All Rights Reserved
 *
 * Definitions for transaction data structures for the buffer cache
 * filesystem journaling support.
 */

#ifndef _LINUX_JBD2_H
#define _LINUX_JBD2_H

/* Allow this file to be included directly into e2fsprogs */
#ifndef __KERNEL__
#include "jfs_compat.h"
#define JBD2_DEBUG
#else

#include <linux/types.h>
#include <linux/buffer_head.h>
#include <linux/journal-head.h>
#include <linux/stddef.h>
#include <linux/mutex.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <linux/bit_spinlock.h>
#include <linux/blkdev.h>
#include <crypto/hash.h>
#endif

#define journal_oom_retry

/*
 * Define JBD2_PARANIOD_IOFAIL to cause a kernel BUG() if ext4 finds
 * certain classes of error which can occur due to failed IOs.  Under
 * normal use we want ext4 to continue after such errors, because
 * hardware _can_ fail, but for debugging purposes when running tests on
 * known-good hardware we may want to trap these errors.
 */
#undef JBD2_PARANOID_IOFAIL

/*
 * The default maximum commit age, in seconds.
 */
#define JBD2_DEFAULT_MAX_COMMIT_AGE

#ifdef CONFIG_JBD2_DEBUG
/*
 * Define JBD2_EXPENSIVE_CHECKING to enable more expensive internal
 * consistency checks.  By default we don't do this unless
 * CONFIG_JBD2_DEBUG is on.
 */
#define JBD2_EXPENSIVE_CHECKING
void __jbd2_debug(int level, const char *file, const char *func,
		  unsigned int line, const char *fmt, ...);

#define jbd2_debug(n, fmt, a...)
#else
#define jbd2_debug
#endif

extern void *jbd2_alloc(size_t size, gfp_t flags);
extern void jbd2_free(void *ptr, size_t size);

#define JBD2_MIN_JOURNAL_BLOCKS
#define JBD2_DEFAULT_FAST_COMMIT_BLOCKS

#ifdef __KERNEL__

/**
 * typedef handle_t - The handle_t type represents a single atomic update being performed by some process.
 *
 * All filesystem modifications made by the process go
 * through this handle.  Recursive operations (such as quota operations)
 * are gathered into a single update.
 *
 * The buffer credits field is used to account for journaled buffers
 * being modified by the running process.  To ensure that there is
 * enough log space for all outstanding operations, we need to limit the
 * number of outstanding buffers possible at any time.  When the
 * operation completes, any buffer credits not used are credited back to
 * the transaction, so that at all times we know how many buffers the
 * outstanding updates on a transaction might possibly touch.
 *
 * This is an opaque datatype.
 **/
handle_t;	/* Atomic operation type */


/**
 * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem.
 *
 * journal_t is linked to from the fs superblock structure.
 *
 * We use the journal_t to keep track of all outstanding transaction
 * activity on the filesystem, and to manage the state of the log
 * writing process.
 *
 * This is an opaque datatype.
 **/
journal_t;	/* Journal control structure */
#endif

/*
 * Internal structures used by the logging mechanism:
 */

#define JBD2_MAGIC_NUMBER

/*
 * On-disk structures
 */

/*
 * Descriptor block types:
 */

#define JBD2_DESCRIPTOR_BLOCK
#define JBD2_COMMIT_BLOCK
#define JBD2_SUPERBLOCK_V1
#define JBD2_SUPERBLOCK_V2
#define JBD2_REVOKE_BLOCK

/*
 * Standard header for all descriptor blocks:
 */
journal_header_t;

/*
 * Checksum types.
 */
#define JBD2_CRC32_CHKSUM
#define JBD2_MD5_CHKSUM
#define JBD2_SHA1_CHKSUM
#define JBD2_CRC32C_CHKSUM

#define JBD2_CRC32_CHKSUM_SIZE

#define JBD2_CHECKSUM_BYTES
/*
 * Commit block header for storing transactional checksums:
 *
 * NOTE: If FEATURE_COMPAT_CHECKSUM (checksum v1) is set, the h_chksum*
 * fields are used to store a checksum of the descriptor and data blocks.
 *
 * If FEATURE_INCOMPAT_CSUM_V2 (checksum v2) is set, then the h_chksum
 * field is used to store crc32c(uuid+commit_block).  Each journal metadata
 * block gets its own checksum, and data block checksums are stored in
 * journal_block_tag (in the descriptor).  The other h_chksum* fields are
 * not used.
 *
 * If FEATURE_INCOMPAT_CSUM_V3 is set, the descriptor block uses
 * journal_block_tag3_t to store a full 32-bit checksum.  Everything else
 * is the same as v2.
 *
 * Checksum v1, v2, and v3 are mutually exclusive features.
 */
struct commit_header {};

/*
 * The block tag: used to describe a single buffer in the journal.
 * t_blocknr_high is only used if INCOMPAT_64BIT is set, so this
 * raw struct shouldn't be used for pointer math or sizeof() - use
 * journal_tag_bytes(journal) instead to compute this.
 */
journal_block_tag3_t;

journal_block_tag_t;

/* Tail of descriptor or revoke block, for checksumming */
struct jbd2_journal_block_tail {};

/*
 * The revoke descriptor: used on disk to describe a series of blocks to
 * be revoked from the log
 */
jbd2_journal_revoke_header_t;

/* Definitions for the journal tag flags word: */
#define JBD2_FLAG_ESCAPE
#define JBD2_FLAG_SAME_UUID
#define JBD2_FLAG_DELETED
#define JBD2_FLAG_LAST_TAG


/*
 * The journal superblock.  All fields are in big-endian byte order.
 */
journal_superblock_t;

#define JBD2_FEATURE_COMPAT_CHECKSUM

#define JBD2_FEATURE_INCOMPAT_REVOKE
#define JBD2_FEATURE_INCOMPAT_64BIT
#define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT
#define JBD2_FEATURE_INCOMPAT_CSUM_V2
#define JBD2_FEATURE_INCOMPAT_CSUM_V3
#define JBD2_FEATURE_INCOMPAT_FAST_COMMIT

/* See "journal feature predicate functions" below */

/* Features known to this kernel version: */
#define JBD2_KNOWN_COMPAT_FEATURES
#define JBD2_KNOWN_ROCOMPAT_FEATURES
#define JBD2_KNOWN_INCOMPAT_FEATURES

#ifdef __KERNEL__

#include <linux/fs.h>
#include <linux/sched.h>

enum jbd_state_bits {};

BUFFER_FNS(JBD, jbd)
BUFFER_FNS(JWrite, jwrite)
BUFFER_FNS(JBDDirty, jbddirty)
TAS_BUFFER_FNS(JBDDirty, jbddirty)
BUFFER_FNS(Revoked, revoked)
TAS_BUFFER_FNS(Revoked, revoked)
BUFFER_FNS(RevokeValid, revokevalid)
TAS_BUFFER_FNS(RevokeValid, revokevalid)
BUFFER_FNS(Freed, freed)
BUFFER_FNS(Shadow, shadow)
BUFFER_FNS(Verified, verified)

static inline struct buffer_head *jh2bh(struct journal_head *jh)
{}

static inline struct journal_head *bh2jh(struct buffer_head *bh)
{}

static inline void jbd_lock_bh_journal_head(struct buffer_head *bh)
{}

static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
{}

#define J_ASSERT(assert)

#define J_ASSERT_BH(bh, expr)
#define J_ASSERT_JH(jh, expr)

#if defined(JBD2_PARANOID_IOFAIL)
#define J_EXPECT
#define J_EXPECT_BH
#define J_EXPECT_JH
#else
#define __journal_expect(expr, why...)
#define J_EXPECT(expr, why...)
#define J_EXPECT_BH(bh, expr, why...)
#define J_EXPECT_JH(jh, expr, why...)
#endif

/* Flags in jbd_inode->i_flags */
#define __JI_COMMIT_RUNNING
#define __JI_WRITE_DATA
#define __JI_WAIT_DATA

/*
 * Commit of the inode data in progress. We use this flag to protect us from
 * concurrent deletion of inode. We cannot use reference to inode for this
 * since we cannot afford doing last iput() on behalf of kjournald
 */
#define JI_COMMIT_RUNNING
/* Write allocated dirty buffers in this inode before commit */
#define JI_WRITE_DATA
/* Wait for outstanding data writes for this inode before commit */
#define JI_WAIT_DATA

/**
 * struct jbd2_inode - The jbd_inode type is the structure linking inodes in
 * ordered mode present in a transaction so that we can sync them during commit.
 */
struct jbd2_inode {};

struct jbd2_revoke_table_s;

/**
 * struct jbd2_journal_handle - The jbd2_journal_handle type is the concrete
 *     type associated with handle_t.
 * @h_transaction: Which compound transaction is this update a part of?
 * @h_journal: Which journal handle belongs to - used iff h_reserved set.
 * @h_rsv_handle: Handle reserved for finishing the logical operation.
 * @h_total_credits: Number of remaining buffers we are allowed to add to
 *	journal. These are dirty buffers and revoke descriptor blocks.
 * @h_revoke_credits: Number of remaining revoke records available for handle
 * @h_ref: Reference count on this handle.
 * @h_err: Field for caller's use to track errors through large fs operations.
 * @h_sync: Flag for sync-on-close.
 * @h_jdata: Flag to force data journaling.
 * @h_reserved: Flag for handle for reserved credits.
 * @h_aborted: Flag indicating fatal error on handle.
 * @h_type: For handle statistics.
 * @h_line_no: For handle statistics.
 * @h_start_jiffies: Handle Start time.
 * @h_requested_credits: Holds @h_total_credits after handle is started.
 * @h_revoke_credits_requested: Holds @h_revoke_credits after handle is started.
 * @saved_alloc_context: Saved context while transaction is open.
 **/

/* Docbook can't yet cope with the bit fields, but will leave the documentation
 * in so it can be fixed later.
 */

struct jbd2_journal_handle
{};


/*
 * Some stats for checkpoint phase
 */
struct transaction_chp_stats_s {};

/* The transaction_t type is the guts of the journaling mechanism.  It
 * tracks a compound transaction through its various states:
 *
 * RUNNING:	accepting new updates
 * LOCKED:	Updates still running but we don't accept new ones
 * RUNDOWN:	Updates are tidying up but have finished requesting
 *		new buffers to modify (state not used for now)
 * FLUSH:       All updates complete, but we are still writing to disk
 * COMMIT:      All data on disk, writing commit record
 * FINISHED:	We still have to keep the transaction for checkpointing.
 *
 * The transaction keeps track of all of the buffers modified by a
 * running transaction, and all of the buffers committed but not yet
 * flushed to home for finished transactions.
 * (Locking Documentation improved by LockDoc)
 */

/*
 * Lock ranking:
 *
 *    j_list_lock
 *      ->jbd_lock_bh_journal_head()	(This is "innermost")
 *
 *    j_state_lock
 *    ->b_state_lock
 *
 *    b_state_lock
 *    ->j_list_lock
 *
 *    j_state_lock
 *    ->j_list_lock			(journal_unmap_buffer)
 *
 */

struct transaction_s
{};

struct transaction_run_stats_s {};

struct transaction_stats_s {};

static inline unsigned long
jbd2_time_diff(unsigned long start, unsigned long end)
{}

#define JBD2_NR_BATCH

enum passtype {};

#define JBD2_FC_REPLAY_STOP
#define JBD2_FC_REPLAY_CONTINUE

/**
 * struct journal_s - The journal_s type is the concrete type associated with
 *     journal_t.
 */
struct journal_s
{};

#define jbd2_might_wait_for_commit(j)

/*
 * We can support any known requested features iff the
 * superblock is not in version 1.  Otherwise we fail to support any
 * extended sb features.
 */
static inline bool jbd2_format_support_feature(journal_t *j)
{}

/* journal feature predicate functions */
#define JBD2_FEATURE_COMPAT_FUNCS(name, flagname)

#define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname)

#define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname)

JBD2_FEATURE_COMPAT_FUNCS()

JBD2_FEATURE_INCOMPAT_FUNCS()
JBD2_FEATURE_INCOMPAT_FUNCS()
JBD2_FEATURE_INCOMPAT_FUNCS()
JBD2_FEATURE_INCOMPAT_FUNCS()
JBD2_FEATURE_INCOMPAT_FUNCS()
JBD2_FEATURE_INCOMPAT_FUNCS()

/* Journal high priority write IO operation flags */
#define JBD2_JOURNAL_REQ_FLAGS

/*
 * Journal flag definitions
 */
#define JBD2_UNMOUNT
#define JBD2_ABORT
#define JBD2_ACK_ERR
#define JBD2_FLUSHED
#define JBD2_LOADED
#define JBD2_BARRIER
#define JBD2_ABORT_ON_SYNCDATA_ERR
#define JBD2_CYCLE_RECORD
#define JBD2_FAST_COMMIT_ONGOING
#define JBD2_FULL_COMMIT_ONGOING
#define JBD2_JOURNAL_FLUSH_DISCARD
#define JBD2_JOURNAL_FLUSH_ZEROOUT
#define JBD2_JOURNAL_FLUSH_VALID

/*
 * Function declarations for the journaling transaction and buffer
 * management
 */

/* Filing buffers */
extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *);
extern bool __jbd2_journal_refile_buffer(struct journal_head *);
extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *);
extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh)
{}
static inline void jbd2_unfile_log_bh(struct buffer_head *bh)
{}

/* Log buffer allocation */
struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int);
void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *);
int jbd2_journal_next_log_block(journal_t *, unsigned long long *);
int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid,
			      unsigned long *block);
int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block);
void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block);

/* Commit management */
extern void jbd2_journal_commit_transaction(journal_t *);

/* Checkpoint list management */
enum jbd2_shrink_type {};

void __jbd2_journal_clean_checkpoint_list(journal_t *journal, enum jbd2_shrink_type type);
unsigned long jbd2_journal_shrink_checkpoint_list(journal_t *journal, unsigned long *nr_to_scan);
int __jbd2_journal_remove_checkpoint(struct journal_head *);
int jbd2_journal_try_remove_checkpoint(struct journal_head *jh);
void jbd2_journal_destroy_checkpoint(journal_t *journal);
void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *);


/*
 * Triggers
 */

struct jbd2_buffer_trigger_type {};

extern void jbd2_buffer_frozen_trigger(struct journal_head *jh,
				       void *mapped_data,
				       struct jbd2_buffer_trigger_type *triggers);
extern void jbd2_buffer_abort_trigger(struct journal_head *jh,
				      struct jbd2_buffer_trigger_type *triggers);

/* Buffer IO */
extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
					      struct journal_head *jh_in,
					      struct buffer_head **bh_out,
					      sector_t blocknr);

/* Transaction cache support */
extern void jbd2_journal_destroy_transaction_cache(void);
extern int __init jbd2_journal_init_transaction_cache(void);
extern void jbd2_journal_free_transaction(transaction_t *);

/*
 * Journal locking.
 *
 * We need to lock the journal during transaction state changes so that nobody
 * ever tries to take a handle on the running transaction while we are in the
 * middle of moving it to the commit phase.  j_state_lock does this.
 *
 * Note that the locking is completely interrupt unsafe.  We never touch
 * journal structures from interrupts.
 */

static inline handle_t *journal_current_handle(void)
{}

/* The journaling code user interface:
 *
 * Create and destroy handles
 * Register buffer modifications against the current transaction.
 */

extern handle_t *jbd2_journal_start(journal_t *, int nblocks);
extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks,
				     int revoke_records, gfp_t gfp_mask,
				     unsigned int type, unsigned int line_no);
extern int	 jbd2_journal_restart(handle_t *, int nblocks);
extern int	 jbd2__journal_restart(handle_t *, int nblocks,
				       int revoke_records, gfp_t gfp_mask);
extern int	 jbd2_journal_start_reserved(handle_t *handle,
				unsigned int type, unsigned int line_no);
extern void	 jbd2_journal_free_reserved(handle_t *handle);
extern int	 jbd2_journal_extend(handle_t *handle, int nblocks,
				     int revoke_records);
extern int	 jbd2_journal_get_write_access(handle_t *, struct buffer_head *);
extern int	 jbd2_journal_get_create_access (handle_t *, struct buffer_head *);
extern int	 jbd2_journal_get_undo_access(handle_t *, struct buffer_head *);
void		 jbd2_journal_set_triggers(struct buffer_head *,
					   struct jbd2_buffer_trigger_type *type);
extern int	 jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *);
extern int	 jbd2_journal_forget (handle_t *, struct buffer_head *);
int jbd2_journal_invalidate_folio(journal_t *, struct folio *,
					size_t offset, size_t length);
bool jbd2_journal_try_to_free_buffers(journal_t *journal, struct folio *folio);
extern int	 jbd2_journal_stop(handle_t *);
extern int	 jbd2_journal_flush(journal_t *journal, unsigned int flags);
extern void	 jbd2_journal_lock_updates (journal_t *);
extern void	 jbd2_journal_unlock_updates (journal_t *);

void jbd2_journal_wait_updates(journal_t *);

extern journal_t * jbd2_journal_init_dev(struct block_device *bdev,
				struct block_device *fs_dev,
				unsigned long long start, int len, int bsize);
extern journal_t * jbd2_journal_init_inode (struct inode *);
extern int	   jbd2_journal_update_format (journal_t *);
extern int	   jbd2_journal_check_used_features
		   (journal_t *, unsigned long, unsigned long, unsigned long);
extern int	   jbd2_journal_check_available_features
		   (journal_t *, unsigned long, unsigned long, unsigned long);
extern int	   jbd2_journal_set_features
		   (journal_t *, unsigned long, unsigned long, unsigned long);
extern void	   jbd2_journal_clear_features
		   (journal_t *, unsigned long, unsigned long, unsigned long);
extern int	   jbd2_journal_load       (journal_t *journal);
extern int	   jbd2_journal_destroy    (journal_t *);
extern int	   jbd2_journal_recover    (journal_t *journal);
extern int	   jbd2_journal_wipe       (journal_t *, int);
extern int	   jbd2_journal_skip_recovery	(journal_t *);
extern void	   jbd2_journal_update_sb_errno(journal_t *);
extern int	   jbd2_journal_update_sb_log_tail	(journal_t *, tid_t,
				unsigned long, blk_opf_t);
extern void	   jbd2_journal_abort      (journal_t *, int);
extern int	   jbd2_journal_errno      (journal_t *);
extern void	   jbd2_journal_ack_err    (journal_t *);
extern int	   jbd2_journal_clear_err  (journal_t *);
extern int	   jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *);
extern int	   jbd2_journal_force_commit(journal_t *);
extern int	   jbd2_journal_force_commit_nested(journal_t *);
extern int	   jbd2_journal_inode_ranged_write(handle_t *handle,
			struct jbd2_inode *inode, loff_t start_byte,
			loff_t length);
extern int	   jbd2_journal_inode_ranged_wait(handle_t *handle,
			struct jbd2_inode *inode, loff_t start_byte,
			loff_t length);
extern int	   jbd2_journal_finish_inode_data_buffers(
			struct jbd2_inode *jinode);
extern int	   jbd2_journal_begin_ordered_truncate(journal_t *journal,
				struct jbd2_inode *inode, loff_t new_size);
extern void	   jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode);
extern void	   jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode);

/*
 * journal_head management
 */
struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh);
struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh);
void jbd2_journal_put_journal_head(struct journal_head *jh);

/*
 * handle management
 */
extern struct kmem_cache *jbd2_handle_cache;

/*
 * This specialized allocator has to be a macro for its allocations to be
 * accounted separately (to have a separate alloc_tag). The typecast is
 * intentional to enforce typesafety.
 */
#define jbd2_alloc_handle(_gfp_flags)

static inline void jbd2_free_handle(handle_t *handle)
{}

/*
 * jbd2_inode management (optional, for those file systems that want to use
 * dynamically allocated jbd2_inode structures)
 */
extern struct kmem_cache *jbd2_inode_cache;

/*
 * This specialized allocator has to be a macro for its allocations to be
 * accounted separately (to have a separate alloc_tag). The typecast is
 * intentional to enforce typesafety.
 */
#define jbd2_alloc_inode(_gfp_flags)

static inline void jbd2_free_inode(struct jbd2_inode *jinode)
{}

/* Primary revoke support */
#define JOURNAL_REVOKE_DEFAULT_HASH
extern int	   jbd2_journal_init_revoke(journal_t *, int);
extern void	   jbd2_journal_destroy_revoke_record_cache(void);
extern void	   jbd2_journal_destroy_revoke_table_cache(void);
extern int __init jbd2_journal_init_revoke_record_cache(void);
extern int __init jbd2_journal_init_revoke_table_cache(void);

extern void	   jbd2_journal_destroy_revoke(journal_t *);
extern int	   jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *);
extern int	   jbd2_journal_cancel_revoke(handle_t *, struct journal_head *);
extern void	   jbd2_journal_write_revoke_records(transaction_t *transaction,
						     struct list_head *log_bufs);

/* Recovery revoke support */
extern int	jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t);
extern int	jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t);
extern void	jbd2_journal_clear_revoke(journal_t *);
extern void	jbd2_journal_switch_revoke_table(journal_t *journal);
extern void	jbd2_clear_buffer_revoked_flags(journal_t *journal);

/*
 * The log thread user interface:
 *
 * Request space in the current transaction, and force transaction commit
 * transitions on demand.
 */

int jbd2_log_start_commit(journal_t *journal, tid_t tid);
int jbd2_journal_start_commit(journal_t *journal, tid_t *tid);
int jbd2_log_wait_commit(journal_t *journal, tid_t tid);
int jbd2_transaction_committed(journal_t *journal, tid_t tid);
int jbd2_complete_transaction(journal_t *journal, tid_t tid);
int jbd2_log_do_checkpoint(journal_t *journal);
int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid);

void __jbd2_log_wait_for_space(journal_t *journal);
extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *);
extern int jbd2_cleanup_journal_tail(journal_t *);

/* Fast commit related APIs */
int jbd2_fc_begin_commit(journal_t *journal, tid_t tid);
int jbd2_fc_end_commit(journal_t *journal);
int jbd2_fc_end_commit_fallback(journal_t *journal);
int jbd2_fc_get_buf(journal_t *journal, struct buffer_head **bh_out);
int jbd2_submit_inode_data(journal_t *journal, struct jbd2_inode *jinode);
int jbd2_wait_inode_data(journal_t *journal, struct jbd2_inode *jinode);
int jbd2_fc_wait_bufs(journal_t *journal, int num_blks);
int jbd2_fc_release_bufs(journal_t *journal);

/*
 * is_journal_abort
 *
 * Simple test wrapper function to test the JBD2_ABORT state flag.  This
 * bit, when set, indicates that we have had a fatal error somewhere,
 * either inside the journaling layer or indicated to us by the client
 * (eg. ext3), and that we and should not commit any further
 * transactions.
 */

static inline int is_journal_aborted(journal_t *journal)
{}

static inline int is_handle_aborted(handle_t *handle)
{}

static inline void jbd2_journal_abort_handle(handle_t *handle)
{}

static inline void jbd2_init_fs_dev_write_error(journal_t *journal)
{}

static inline int jbd2_check_fs_dev_write_error(journal_t *journal)
{}

#endif /* __KERNEL__   */

/* Comparison functions for transaction IDs: perform comparisons using
 * modulo arithmetic so that they work over sequence number wraps. */

static inline int tid_gt(tid_t x, tid_t y)
{}

static inline int tid_geq(tid_t x, tid_t y)
{}

extern int jbd2_journal_blocks_per_page(struct inode *inode);
extern size_t journal_tag_bytes(journal_t *journal);

static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j)
{}

static inline int jbd2_journal_has_csum_v2or3(journal_t *journal)
{}

static inline int jbd2_journal_get_num_fc_blks(journal_superblock_t *jsb)
{}

/*
 * Return number of free blocks in the log. Must be called under j_state_lock.
 */
static inline unsigned long jbd2_log_space_left(journal_t *journal)
{}

/*
 * Definitions which augment the buffer_head layer
 */

/* journaling buffer types */
#define BJ_None
#define BJ_Metadata
#define BJ_Forget
#define BJ_Shadow
#define BJ_Reserved
#define BJ_Types

/* JBD uses a CRC32 checksum */
#define JBD_MAX_CHECKSUM_SIZE

static inline u32 jbd2_chksum(journal_t *journal, u32 crc,
			      const void *address, unsigned int length)
{}

/* Return most recent uncommitted transaction */
static inline tid_t  jbd2_get_latest_transaction(journal_t *journal)
{}

static inline int jbd2_handle_buffer_credits(handle_t *handle)
{}

#ifdef __KERNEL__

#define buffer_trace_init(bh)
#define print_buffer_fields(bh)
#define print_buffer_trace(bh)
#define BUFFER_TRACE(bh, info)
#define BUFFER_TRACE2(bh, bh2, info)
#define JBUFFER_TRACE(jh, info)

#endif	/* __KERNEL__ */

#define EFSBADCRC
#define EFSCORRUPTED

#endif	/* _LINUX_JBD2_H */