Edit File: jbd.h
/* * 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/bit_spinlock.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; #define jbd_debug(n, f, a...) \ do { \ if ((n) <= journal_enable_debug) { \ printk (KERN_DEBUG "(%s, %d): %s: ", \ __FILE__, __LINE__, __func__); \ printk (f, ## a); \ } \ } while (0) #else #define jbd_debug(f, 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 long); 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 *); /* Debugging code only: */ #define jbd_ENOSYS() \ do { \ printk (KERN_ERR "JBD unimplemented function %s\n", __func__); \ current->state = TASK_UNINTERRUPTIBLE; \ schedule(); \ } while (1) /* * 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 */