+++ /dev/null
-/*
- * linux/include/linux/jbd.h
- *
- * Written by Stephen C. Tweedie <sct@redhat.com>
- *
- * Copyright 1998-2000 Red Hat, Inc --- All Rights Reserved
- *
- * This file is part of the Linux kernel and is made available under
- * the terms of the GNU General Public License, version 2, or at your
- * option, any later version, incorporated herein by reference.
- *
- * Definitions for transaction data structures for the buffer cache
- * filesystem journaling support.
- */
-
-#ifndef _LINUX_JBD_H
-#define _LINUX_JBD_H
-
-/* Allow this file to be included directly into e2fsprogs */
-#ifndef __KERNEL__
-#include "jfs_compat.h"
-#define JFS_DEBUG
-#define jfs_debug jbd_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/lockdep.h>
-#include <linux/slab.h>
-
-#define journal_oom_retry 1
-
-/*
- * Define JBD_PARANOID_IOFAIL to cause a kernel BUG() if ext3 finds
- * certain classes of error which can occur due to failed IOs. Under
- * normal use we want ext3 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 JBD_PARANOID_IOFAIL
-
-/*
- * The default maximum commit age, in seconds.
- */
-#define JBD_DEFAULT_MAX_COMMIT_AGE 5
-
-#ifdef CONFIG_JBD_DEBUG
-/*
- * Define JBD_EXPENSIVE_CHECKING to enable more expensive internal
- * consistency checks. By default we don't do this unless
- * CONFIG_JBD_DEBUG is on.
- */
-#define JBD_EXPENSIVE_CHECKING
-extern u8 journal_enable_debug;
-
-void __jbd_debug(int level, const char *file, const char *func,
- unsigned int line, const char *fmt, ...);
-
-#define jbd_debug(n, fmt, a...) \
- __jbd_debug((n), __FILE__, __func__, __LINE__, (fmt), ##a)
-#else
-#define jbd_debug(n, fmt, a...) /**/
-#endif
-
-static inline void *jbd_alloc(size_t size, gfp_t flags)
-{
- return (void *)__get_free_pages(flags, get_order(size));
-}
-
-static inline void jbd_free(void *ptr, size_t size)
-{
- free_pages((unsigned long)ptr, get_order(size));
-}
-
-#define JFS_MIN_JOURNAL_BLOCKS 1024
-
-
-/**
- * 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.
- **/
-typedef struct handle_s 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.
- **/
-typedef struct journal_s journal_t; /* Journal control structure */
-#endif
-
-/*
- * Internal structures used by the logging mechanism:
- */
-
-#define JFS_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */
-
-/*
- * On-disk structures
- */
-
-/*
- * Descriptor block types:
- */
-
-#define JFS_DESCRIPTOR_BLOCK 1
-#define JFS_COMMIT_BLOCK 2
-#define JFS_SUPERBLOCK_V1 3
-#define JFS_SUPERBLOCK_V2 4
-#define JFS_REVOKE_BLOCK 5
-
-/*
- * Standard header for all descriptor blocks:
- */
-typedef struct journal_header_s
-{
- __be32 h_magic;
- __be32 h_blocktype;
- __be32 h_sequence;
-} journal_header_t;
-
-
-/*
- * The block tag: used to describe a single buffer in the journal
- */
-typedef struct journal_block_tag_s
-{
- __be32 t_blocknr; /* The on-disk block number */
- __be32 t_flags; /* See below */
-} journal_block_tag_t;
-
-/*
- * The revoke descriptor: used on disk to describe a series of blocks to
- * be revoked from the log
- */
-typedef struct journal_revoke_header_s
-{
- journal_header_t r_header;
- __be32 r_count; /* Count of bytes used in the block */
-} journal_revoke_header_t;
-
-
-/* Definitions for the journal tag flags word: */
-#define JFS_FLAG_ESCAPE 1 /* on-disk block is escaped */
-#define JFS_FLAG_SAME_UUID 2 /* block has same uuid as previous */
-#define JFS_FLAG_DELETED 4 /* block deleted by this transaction */
-#define JFS_FLAG_LAST_TAG 8 /* last tag in this descriptor block */
-
-
-/*
- * The journal superblock. All fields are in big-endian byte order.
- */
-typedef struct journal_superblock_s
-{
-/* 0x0000 */
- journal_header_t s_header;
-
-/* 0x000C */
- /* Static information describing the journal */
- __be32 s_blocksize; /* journal device blocksize */
- __be32 s_maxlen; /* total blocks in journal file */
- __be32 s_first; /* first block of log information */
-
-/* 0x0018 */
- /* Dynamic information describing the current state of the log */
- __be32 s_sequence; /* first commit ID expected in log */
- __be32 s_start; /* blocknr of start of log */
-
-/* 0x0020 */
- /* Error value, as set by journal_abort(). */
- __be32 s_errno;
-
-/* 0x0024 */
- /* Remaining fields are only valid in a version-2 superblock */
- __be32 s_feature_compat; /* compatible feature set */
- __be32 s_feature_incompat; /* incompatible feature set */
- __be32 s_feature_ro_compat; /* readonly-compatible feature set */
-/* 0x0030 */
- __u8 s_uuid[16]; /* 128-bit uuid for journal */
-
-/* 0x0040 */
- __be32 s_nr_users; /* Nr of filesystems sharing log */
-
- __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/
-
-/* 0x0048 */
- __be32 s_max_transaction; /* Limit of journal blocks per trans.*/
- __be32 s_max_trans_data; /* Limit of data blocks per trans. */
-
-/* 0x0050 */
- __u32 s_padding[44];
-
-/* 0x0100 */
- __u8 s_users[16*48]; /* ids of all fs'es sharing the log */
-/* 0x0400 */
-} journal_superblock_t;
-
-#define JFS_HAS_COMPAT_FEATURE(j,mask) \
- ((j)->j_format_version >= 2 && \
- ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask))))
-#define JFS_HAS_RO_COMPAT_FEATURE(j,mask) \
- ((j)->j_format_version >= 2 && \
- ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask))))
-#define JFS_HAS_INCOMPAT_FEATURE(j,mask) \
- ((j)->j_format_version >= 2 && \
- ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask))))
-
-#define JFS_FEATURE_INCOMPAT_REVOKE 0x00000001
-
-/* Features known to this kernel version: */
-#define JFS_KNOWN_COMPAT_FEATURES 0
-#define JFS_KNOWN_ROCOMPAT_FEATURES 0
-#define JFS_KNOWN_INCOMPAT_FEATURES JFS_FEATURE_INCOMPAT_REVOKE
-
-#ifdef __KERNEL__
-
-#include <linux/fs.h>
-#include <linux/sched.h>
-
-enum jbd_state_bits {
- BH_JBD /* Has an attached ext3 journal_head */
- = BH_PrivateStart,
- BH_JWrite, /* Being written to log (@@@ DEBUGGING) */
- BH_Freed, /* Has been freed (truncated) */
- BH_Revoked, /* Has been revoked from the log */
- BH_RevokeValid, /* Revoked flag is valid */
- BH_JBDDirty, /* Is dirty but journaled */
- BH_State, /* Pins most journal_head state */
- BH_JournalHead, /* Pins bh->b_private and jh->b_bh */
- BH_Unshadow, /* Dummy bit, for BJ_Shadow wakeup filtering */
- BH_JBDPrivateStart, /* First bit available for private use by FS */
-};
-
-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)
-
-#include <linux/jbd_common.h>
-
-#define J_ASSERT(assert) BUG_ON(!(assert))
-
-#define J_ASSERT_BH(bh, expr) J_ASSERT(expr)
-#define J_ASSERT_JH(jh, expr) J_ASSERT(expr)
-
-#if defined(JBD_PARANOID_IOFAIL)
-#define J_EXPECT(expr, why...) J_ASSERT(expr)
-#define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr)
-#define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr)
-#else
-#define __journal_expect(expr, why...) \
- ({ \
- int val = (expr); \
- if (!val) { \
- printk(KERN_ERR \
- "EXT3-fs unexpected failure: %s;\n",# expr); \
- printk(KERN_ERR why "\n"); \
- } \
- val; \
- })
-#define J_EXPECT(expr, why...) __journal_expect(expr, ## why)
-#define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why)
-#define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why)
-#endif
-
-struct jbd_revoke_table_s;
-
-/**
- * struct handle_s - this is the concrete type associated with handle_t.
- * @h_transaction: Which compound transaction is this update a part of?
- * @h_buffer_credits: Number of remaining buffers we are allowed to dirty.
- * @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_aborted: flag indicating fatal error on handle
- * @h_lockdep_map: lockdep info for debugging lock problems
- */
-struct handle_s
-{
- /* Which compound transaction is this update a part of? */
- transaction_t *h_transaction;
-
- /* Number of remaining buffers we are allowed to dirty: */
- int h_buffer_credits;
-
- /* Reference count on this handle */
- int h_ref;
-
- /* Field for caller's use to track errors through large fs */
- /* operations */
- int h_err;
-
- /* Flags [no locking] */
- unsigned int h_sync: 1; /* sync-on-close */
- unsigned int h_jdata: 1; /* force data journaling */
- unsigned int h_aborted: 1; /* fatal error on handle */
-
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- struct lockdep_map h_lockdep_map;
-#endif
-};
-
-
-/* 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.
- */
-
-/*
- * Lock ranking:
- *
- * j_list_lock
- * ->jbd_lock_bh_journal_head() (This is "innermost")
- *
- * j_state_lock
- * ->jbd_lock_bh_state()
- *
- * jbd_lock_bh_state()
- * ->j_list_lock
- *
- * j_state_lock
- * ->t_handle_lock
- *
- * j_state_lock
- * ->j_list_lock (journal_unmap_buffer)
- *
- */
-
-struct transaction_s
-{
- /* Pointer to the journal for this transaction. [no locking] */
- journal_t *t_journal;
-
- /* Sequence number for this transaction [no locking] */
- tid_t t_tid;
-
- /*
- * Transaction's current state
- * [no locking - only kjournald alters this]
- * [j_list_lock] guards transition of a transaction into T_FINISHED
- * state and subsequent call of __journal_drop_transaction()
- * FIXME: needs barriers
- * KLUDGE: [use j_state_lock]
- */
- enum {
- T_RUNNING,
- T_LOCKED,
- T_FLUSH,
- T_COMMIT,
- T_COMMIT_RECORD,
- T_FINISHED
- } t_state;
-
- /*
- * Where in the log does this transaction's commit start? [no locking]
- */
- unsigned int t_log_start;
-
- /* Number of buffers on the t_buffers list [j_list_lock] */
- int t_nr_buffers;
-
- /*
- * Doubly-linked circular list of all buffers reserved but not yet
- * modified by this transaction [j_list_lock]
- */
- struct journal_head *t_reserved_list;
-
- /*
- * Doubly-linked circular list of all buffers under writeout during
- * commit [j_list_lock]
- */
- struct journal_head *t_locked_list;
-
- /*
- * Doubly-linked circular list of all metadata buffers owned by this
- * transaction [j_list_lock]
- */
- struct journal_head *t_buffers;
-
- /*
- * Doubly-linked circular list of all data buffers still to be
- * flushed before this transaction can be committed [j_list_lock]
- */
- struct journal_head *t_sync_datalist;
-
- /*
- * Doubly-linked circular list of all forget buffers (superseded
- * buffers which we can un-checkpoint once this transaction commits)
- * [j_list_lock]
- */
- struct journal_head *t_forget;
-
- /*
- * Doubly-linked circular list of all buffers still to be flushed before
- * this transaction can be checkpointed. [j_list_lock]
- */
- struct journal_head *t_checkpoint_list;
-
- /*
- * Doubly-linked circular list of all buffers submitted for IO while
- * checkpointing. [j_list_lock]
- */
- struct journal_head *t_checkpoint_io_list;
-
- /*
- * Doubly-linked circular list of temporary buffers currently undergoing
- * IO in the log [j_list_lock]
- */
- struct journal_head *t_iobuf_list;
-
- /*
- * Doubly-linked circular list of metadata buffers being shadowed by log
- * IO. The IO buffers on the iobuf list and the shadow buffers on this
- * list match each other one for one at all times. [j_list_lock]
- */
- struct journal_head *t_shadow_list;
-
- /*
- * Doubly-linked circular list of control buffers being written to the
- * log. [j_list_lock]
- */
- struct journal_head *t_log_list;
-
- /*
- * Protects info related to handles
- */
- spinlock_t t_handle_lock;
-
- /*
- * Number of outstanding updates running on this transaction
- * [t_handle_lock]
- */
- int t_updates;
-
- /*
- * Number of buffers reserved for use by all handles in this transaction
- * handle but not yet modified. [t_handle_lock]
- */
- int t_outstanding_credits;
-
- /*
- * Forward and backward links for the circular list of all transactions
- * awaiting checkpoint. [j_list_lock]
- */
- transaction_t *t_cpnext, *t_cpprev;
-
- /*
- * When will the transaction expire (become due for commit), in jiffies?
- * [no locking]
- */
- unsigned long t_expires;
-
- /*
- * When this transaction started, in nanoseconds [no locking]
- */
- ktime_t t_start_time;
-
- /*
- * How many handles used this transaction? [t_handle_lock]
- */
- int t_handle_count;
-};
-
-/**
- * struct journal_s - this is the concrete type associated with journal_t.
- * @j_flags: General journaling state flags
- * @j_errno: Is there an outstanding uncleared error on the journal (from a
- * prior abort)?
- * @j_sb_buffer: First part of superblock buffer
- * @j_superblock: Second part of superblock buffer
- * @j_format_version: Version of the superblock format
- * @j_state_lock: Protect the various scalars in the journal
- * @j_barrier_count: Number of processes waiting to create a barrier lock
- * @j_running_transaction: The current running transaction..
- * @j_committing_transaction: the transaction we are pushing to disk
- * @j_checkpoint_transactions: a linked circular list of all transactions
- * waiting for checkpointing
- * @j_wait_transaction_locked: Wait queue for waiting for a locked transaction
- * to start committing, or for a barrier lock to be released
- * @j_wait_logspace: Wait queue for waiting for checkpointing to complete
- * @j_wait_done_commit: Wait queue for waiting for commit to complete
- * @j_wait_checkpoint: Wait queue to trigger checkpointing
- * @j_wait_commit: Wait queue to trigger commit
- * @j_wait_updates: Wait queue to wait for updates to complete
- * @j_checkpoint_mutex: Mutex for locking against concurrent checkpoints
- * @j_head: Journal head - identifies the first unused block in the journal
- * @j_tail: Journal tail - identifies the oldest still-used block in the
- * journal.
- * @j_free: Journal free - how many free blocks are there in the journal?
- * @j_first: The block number of the first usable block
- * @j_last: The block number one beyond the last usable block
- * @j_dev: Device where we store the journal
- * @j_blocksize: blocksize for the location where we store the journal.
- * @j_blk_offset: starting block offset for into the device where we store the
- * journal
- * @j_fs_dev: Device which holds the client fs. For internal journal this will
- * be equal to j_dev
- * @j_maxlen: Total maximum capacity of the journal region on disk.
- * @j_list_lock: Protects the buffer lists and internal buffer state.
- * @j_inode: Optional inode where we store the journal. If present, all journal
- * block numbers are mapped into this inode via bmap().
- * @j_tail_sequence: Sequence number of the oldest transaction in the log
- * @j_transaction_sequence: Sequence number of the next transaction to grant
- * @j_commit_sequence: Sequence number of the most recently committed
- * transaction
- * @j_commit_request: Sequence number of the most recent transaction wanting
- * commit
- * @j_commit_waited: Sequence number of the most recent transaction someone
- * is waiting for to commit.
- * @j_uuid: Uuid of client object.
- * @j_task: Pointer to the current commit thread for this journal
- * @j_max_transaction_buffers: Maximum number of metadata buffers to allow in a
- * single compound commit transaction
- * @j_commit_interval: What is the maximum transaction lifetime before we begin
- * a commit?
- * @j_commit_timer: The timer used to wakeup the commit thread
- * @j_revoke_lock: Protect the revoke table
- * @j_revoke: The revoke table - maintains the list of revoked blocks in the
- * current transaction.
- * @j_revoke_table: alternate revoke tables for j_revoke
- * @j_wbuf: array of buffer_heads for journal_commit_transaction
- * @j_wbufsize: maximum number of buffer_heads allowed in j_wbuf, the
- * number that will fit in j_blocksize
- * @j_last_sync_writer: most recent pid which did a synchronous write
- * @j_average_commit_time: the average amount of time in nanoseconds it
- * takes to commit a transaction to the disk.
- * @j_private: An opaque pointer to fs-private information.
- */
-
-struct journal_s
-{
- /* General journaling state flags [j_state_lock] */
- unsigned long j_flags;
-
- /*
- * Is there an outstanding uncleared error on the journal (from a prior
- * abort)? [j_state_lock]
- */
- int j_errno;
-
- /* The superblock buffer */
- struct buffer_head *j_sb_buffer;
- journal_superblock_t *j_superblock;
-
- /* Version of the superblock format */
- int j_format_version;
-
- /*
- * Protect the various scalars in the journal
- */
- spinlock_t j_state_lock;
-
- /*
- * Number of processes waiting to create a barrier lock [j_state_lock]
- */
- int j_barrier_count;
-
- /*
- * Transactions: The current running transaction...
- * [j_state_lock] [caller holding open handle]
- */
- transaction_t *j_running_transaction;
-
- /*
- * the transaction we are pushing to disk
- * [j_state_lock] [caller holding open handle]
- */
- transaction_t *j_committing_transaction;
-
- /*
- * ... and a linked circular list of all transactions waiting for
- * checkpointing. [j_list_lock]
- */
- transaction_t *j_checkpoint_transactions;
-
- /*
- * Wait queue for waiting for a locked transaction to start committing,
- * or for a barrier lock to be released
- */
- wait_queue_head_t j_wait_transaction_locked;
-
- /* Wait queue for waiting for checkpointing to complete */
- wait_queue_head_t j_wait_logspace;
-
- /* Wait queue for waiting for commit to complete */
- wait_queue_head_t j_wait_done_commit;
-
- /* Wait queue to trigger checkpointing */
- wait_queue_head_t j_wait_checkpoint;
-
- /* Wait queue to trigger commit */
- wait_queue_head_t j_wait_commit;
-
- /* Wait queue to wait for updates to complete */
- wait_queue_head_t j_wait_updates;
-
- /* Semaphore for locking against concurrent checkpoints */
- struct mutex j_checkpoint_mutex;
-
- /*
- * Journal head: identifies the first unused block in the journal.
- * [j_state_lock]
- */
- unsigned int j_head;
-
- /*
- * Journal tail: identifies the oldest still-used block in the journal.
- * [j_state_lock]
- */
- unsigned int j_tail;
-
- /*
- * Journal free: how many free blocks are there in the journal?
- * [j_state_lock]
- */
- unsigned int j_free;
-
- /*
- * Journal start and end: the block numbers of the first usable block
- * and one beyond the last usable block in the journal. [j_state_lock]
- */
- unsigned int j_first;
- unsigned int j_last;
-
- /*
- * Device, blocksize and starting block offset for the location where we
- * store the journal.
- */
- struct block_device *j_dev;
- int j_blocksize;
- unsigned int j_blk_offset;
-
- /*
- * Device which holds the client fs. For internal journal this will be
- * equal to j_dev.
- */
- struct block_device *j_fs_dev;
-
- /* Total maximum capacity of the journal region on disk. */
- unsigned int j_maxlen;
-
- /*
- * Protects the buffer lists and internal buffer state.
- */
- spinlock_t j_list_lock;
-
- /* Optional inode where we store the journal. If present, all */
- /* journal block numbers are mapped into this inode via */
- /* bmap(). */
- struct inode *j_inode;
-
- /*
- * Sequence number of the oldest transaction in the log [j_state_lock]
- */
- tid_t j_tail_sequence;
-
- /*
- * Sequence number of the next transaction to grant [j_state_lock]
- */
- tid_t j_transaction_sequence;
-
- /*
- * Sequence number of the most recently committed transaction
- * [j_state_lock].
- */
- tid_t j_commit_sequence;
-
- /*
- * Sequence number of the most recent transaction wanting commit
- * [j_state_lock]
- */
- tid_t j_commit_request;
-
- /*
- * Sequence number of the most recent transaction someone is waiting
- * for to commit.
- * [j_state_lock]
- */
- tid_t j_commit_waited;
-
- /*
- * Journal uuid: identifies the object (filesystem, LVM volume etc)
- * backed by this journal. This will eventually be replaced by an array
- * of uuids, allowing us to index multiple devices within a single
- * journal and to perform atomic updates across them.
- */
- __u8 j_uuid[16];
-
- /* Pointer to the current commit thread for this journal */
- struct task_struct *j_task;
-
- /*
- * Maximum number of metadata buffers to allow in a single compound
- * commit transaction
- */
- int j_max_transaction_buffers;
-
- /*
- * What is the maximum transaction lifetime before we begin a commit?
- */
- unsigned long j_commit_interval;
-
- /* The timer used to wakeup the commit thread: */
- struct timer_list j_commit_timer;
-
- /*
- * The revoke table: maintains the list of revoked blocks in the
- * current transaction. [j_revoke_lock]
- */
- spinlock_t j_revoke_lock;
- struct jbd_revoke_table_s *j_revoke;
- struct jbd_revoke_table_s *j_revoke_table[2];
-
- /*
- * array of bhs for journal_commit_transaction
- */
- struct buffer_head **j_wbuf;
- int j_wbufsize;
-
- /*
- * this is the pid of the last person to run a synchronous operation
- * through the journal.
- */
- pid_t j_last_sync_writer;
-
- /*
- * the average amount of time in nanoseconds it takes to commit a
- * transaction to the disk. [j_state_lock]
- */
- u64 j_average_commit_time;
-
- /*
- * An opaque pointer to fs-private information. ext3 puts its
- * superblock pointer here
- */
- void *j_private;
-};
-
-/*
- * Journal flag definitions
- */
-#define JFS_UNMOUNT 0x001 /* Journal thread is being destroyed */
-#define JFS_ABORT 0x002 /* Journaling has been aborted for errors. */
-#define JFS_ACK_ERR 0x004 /* The errno in the sb has been acked */
-#define JFS_FLUSHED 0x008 /* The journal superblock has been flushed */
-#define JFS_LOADED 0x010 /* The journal superblock has been loaded */
-#define JFS_BARRIER 0x020 /* Use IDE barriers */
-#define JFS_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file
- * data write error in ordered
- * mode */
-
-/*
- * Function declarations for the journaling transaction and buffer
- * management
- */
-
-/* Filing buffers */
-extern void journal_unfile_buffer(journal_t *, struct journal_head *);
-extern void __journal_unfile_buffer(struct journal_head *);
-extern void __journal_refile_buffer(struct journal_head *);
-extern void journal_refile_buffer(journal_t *, struct journal_head *);
-extern void __journal_file_buffer(struct journal_head *, transaction_t *, int);
-extern void __journal_free_buffer(struct journal_head *bh);
-extern void journal_file_buffer(struct journal_head *, transaction_t *, int);
-extern void __journal_clean_data_list(transaction_t *transaction);
-
-/* Log buffer allocation */
-extern struct journal_head * journal_get_descriptor_buffer(journal_t *);
-int journal_next_log_block(journal_t *, unsigned int *);
-
-/* Commit management */
-extern void journal_commit_transaction(journal_t *);
-
-/* Checkpoint list management */
-int __journal_clean_checkpoint_list(journal_t *journal);
-int __journal_remove_checkpoint(struct journal_head *);
-void __journal_insert_checkpoint(struct journal_head *, transaction_t *);
-
-/* Buffer IO */
-extern int
-journal_write_metadata_buffer(transaction_t *transaction,
- struct journal_head *jh_in,
- struct journal_head **jh_out,
- unsigned int blocknr);
-
-/* Transaction locking */
-extern void __wait_on_journal (journal_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)
-{
- return current->journal_info;
-}
-
-/* The journaling code user interface:
- *
- * Create and destroy handles
- * Register buffer modifications against the current transaction.
- */
-
-extern handle_t *journal_start(journal_t *, int nblocks);
-extern int journal_restart (handle_t *, int nblocks);
-extern int journal_extend (handle_t *, int nblocks);
-extern int journal_get_write_access(handle_t *, struct buffer_head *);
-extern int journal_get_create_access (handle_t *, struct buffer_head *);
-extern int journal_get_undo_access(handle_t *, struct buffer_head *);
-extern int journal_dirty_data (handle_t *, struct buffer_head *);
-extern int journal_dirty_metadata (handle_t *, struct buffer_head *);
-extern void journal_release_buffer (handle_t *, struct buffer_head *);
-extern int journal_forget (handle_t *, struct buffer_head *);
-extern void journal_sync_buffer (struct buffer_head *);
-extern void journal_invalidatepage(journal_t *,
- struct page *, unsigned int, unsigned int);
-extern int journal_try_to_free_buffers(journal_t *, struct page *, gfp_t);
-extern int journal_stop(handle_t *);
-extern int journal_flush (journal_t *);
-extern void journal_lock_updates (journal_t *);
-extern void journal_unlock_updates (journal_t *);
-
-extern journal_t * journal_init_dev(struct block_device *bdev,
- struct block_device *fs_dev,
- int start, int len, int bsize);
-extern journal_t * journal_init_inode (struct inode *);
-extern int journal_update_format (journal_t *);
-extern int journal_check_used_features
- (journal_t *, unsigned long, unsigned long, unsigned long);
-extern int journal_check_available_features
- (journal_t *, unsigned long, unsigned long, unsigned long);
-extern int journal_set_features
- (journal_t *, unsigned long, unsigned long, unsigned long);
-extern int journal_create (journal_t *);
-extern int journal_load (journal_t *journal);
-extern int journal_destroy (journal_t *);
-extern int journal_recover (journal_t *journal);
-extern int journal_wipe (journal_t *, int);
-extern int journal_skip_recovery (journal_t *);
-extern void journal_update_sb_log_tail (journal_t *, tid_t, unsigned int,
- int);
-extern void journal_abort (journal_t *, int);
-extern int journal_errno (journal_t *);
-extern void journal_ack_err (journal_t *);
-extern int journal_clear_err (journal_t *);
-extern int journal_bmap(journal_t *, unsigned int, unsigned int *);
-extern int journal_force_commit(journal_t *);
-
-/*
- * journal_head management
- */
-struct journal_head *journal_add_journal_head(struct buffer_head *bh);
-struct journal_head *journal_grab_journal_head(struct buffer_head *bh);
-void journal_put_journal_head(struct journal_head *jh);
-
-/*
- * handle management
- */
-extern struct kmem_cache *jbd_handle_cache;
-
-static inline handle_t *jbd_alloc_handle(gfp_t gfp_flags)
-{
- return kmem_cache_zalloc(jbd_handle_cache, gfp_flags);
-}
-
-static inline void jbd_free_handle(handle_t *handle)
-{
- kmem_cache_free(jbd_handle_cache, handle);
-}
-
-/* Primary revoke support */
-#define JOURNAL_REVOKE_DEFAULT_HASH 256
-extern int journal_init_revoke(journal_t *, int);
-extern void journal_destroy_revoke_caches(void);
-extern int journal_init_revoke_caches(void);
-
-extern void journal_destroy_revoke(journal_t *);
-extern int journal_revoke (handle_t *,
- unsigned int, struct buffer_head *);
-extern int journal_cancel_revoke(handle_t *, struct journal_head *);
-extern void journal_write_revoke_records(journal_t *,
- transaction_t *, int);
-
-/* Recovery revoke support */
-extern int journal_set_revoke(journal_t *, unsigned int, tid_t);
-extern int journal_test_revoke(journal_t *, unsigned int, tid_t);
-extern void journal_clear_revoke(journal_t *);
-extern void journal_switch_revoke_table(journal_t *journal);
-extern void journal_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 __log_space_left(journal_t *); /* Called with journal locked */
-int log_start_commit(journal_t *journal, tid_t tid);
-int __log_start_commit(journal_t *journal, tid_t tid);
-int journal_start_commit(journal_t *journal, tid_t *tid);
-int journal_force_commit_nested(journal_t *journal);
-int log_wait_commit(journal_t *journal, tid_t tid);
-int log_do_checkpoint(journal_t *journal);
-int journal_trans_will_send_data_barrier(journal_t *journal, tid_t tid);
-
-void __log_wait_for_space(journal_t *journal);
-extern void __journal_drop_transaction(journal_t *, transaction_t *);
-extern int cleanup_journal_tail(journal_t *);
-
-/*
- * is_journal_abort
- *
- * Simple test wrapper function to test the JFS_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)
-{
- return journal->j_flags & JFS_ABORT;
-}
-
-static inline int is_handle_aborted(handle_t *handle)
-{
- if (handle->h_aborted)
- return 1;
- return is_journal_aborted(handle->h_transaction->t_journal);
-}
-
-static inline void journal_abort_handle(handle_t *handle)
-{
- handle->h_aborted = 1;
-}
-
-#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)
-{
- int difference = (x - y);
- return (difference > 0);
-}
-
-static inline int tid_geq(tid_t x, tid_t y)
-{
- int difference = (x - y);
- return (difference >= 0);
-}
-
-extern int journal_blocks_per_page(struct inode *inode);
-
-/*
- * Return the minimum number of blocks which must be free in the journal
- * before a new transaction may be started. Must be called under j_state_lock.
- */
-static inline int jbd_space_needed(journal_t *journal)
-{
- int nblocks = journal->j_max_transaction_buffers;
- if (journal->j_committing_transaction)
- nblocks += journal->j_committing_transaction->
- t_outstanding_credits;
- return nblocks;
-}
-
-/*
- * Definitions which augment the buffer_head layer
- */
-
-/* journaling buffer types */
-#define BJ_None 0 /* Not journaled */
-#define BJ_SyncData 1 /* Normal data: flush before commit */
-#define BJ_Metadata 2 /* Normal journaled metadata */
-#define BJ_Forget 3 /* Buffer superseded by this transaction */
-#define BJ_IO 4 /* Buffer is for temporary IO use */
-#define BJ_Shadow 5 /* Buffer contents being shadowed to the log */
-#define BJ_LogCtl 6 /* Buffer contains log descriptors */
-#define BJ_Reserved 7 /* Buffer is reserved for access by journal */
-#define BJ_Locked 8 /* Locked for I/O during commit */
-#define BJ_Types 9
-
-extern int jbd_blocks_per_page(struct inode *inode);
-
-#ifdef __KERNEL__
-
-#define buffer_trace_init(bh) do {} while (0)
-#define print_buffer_fields(bh) do {} while (0)
-#define print_buffer_trace(bh) do {} while (0)
-#define BUFFER_TRACE(bh, info) do {} while (0)
-#define BUFFER_TRACE2(bh, bh2, info) do {} while (0)
-#define JBUFFER_TRACE(jh, info) do {} while (0)
-
-#endif /* __KERNEL__ */
-
-#endif /* _LINUX_JBD_H */
Code Review / kvmfornfv.git / blobdiff