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"
23 #define jfs_debug jbd_debug
26 #include <linux/types.h>
27 #include <linux/buffer_head.h>
28 #include <linux/journal-head.h>
29 #include <linux/stddef.h>
30 #include <linux/bit_spinlock.h>
31 #include <linux/mutex.h>
32 #include <linux/timer.h>
34 #include <asm/semaphore.h>
37 #define journal_oom_retry 1
40 * Define JBD_PARANIOD_IOFAIL to cause a kernel BUG() if ext3 finds
41 * certain classes of error which can occur due to failed IOs. Under
42 * normal use we want ext3 to continue after such errors, because
43 * hardware _can_ fail, but for debugging purposes when running tests on
44 * known-good hardware we may want to trap these errors.
46 #undef JBD_PARANOID_IOFAIL
49 * The default maximum commit age, in seconds.
51 #define JBD_DEFAULT_MAX_COMMIT_AGE 5
53 #ifdef CONFIG_JBD_DEBUG
55 * Define JBD_EXPENSIVE_CHECKING to enable more expensive internal
56 * consistency checks. By default we don't do this unless
57 * CONFIG_JBD_DEBUG is on.
59 #define JBD_EXPENSIVE_CHECKING
60 extern int jbd2_journal_enable_debug;
62 #define jbd_debug(n, f, a...) \
64 if ((n) <= jbd2_journal_enable_debug) { \
65 printk (KERN_DEBUG "(%s, %d): %s: ", \
66 __FILE__, __LINE__, __FUNCTION__); \
71 #define jbd_debug(f, a...) /**/
74 extern void * __jbd2_kmalloc (const char *where, size_t size, gfp_t flags, int retry);
75 extern void * jbd2_slab_alloc(size_t size, gfp_t flags);
76 extern void jbd2_slab_free(void *ptr, size_t size);
78 #define jbd_kmalloc(size, flags) \
79 __jbd2_kmalloc(__FUNCTION__, (size), (flags), journal_oom_retry)
80 #define jbd_rep_kmalloc(size, flags) \
81 __jbd2_kmalloc(__FUNCTION__, (size), (flags), 1)
83 #define JBD2_MIN_JOURNAL_BLOCKS 1024
88 * typedef handle_t - The handle_t type represents a single atomic update being performed by some process.
90 * All filesystem modifications made by the process go
91 * through this handle. Recursive operations (such as quota operations)
92 * are gathered into a single update.
94 * The buffer credits field is used to account for journaled buffers
95 * being modified by the running process. To ensure that there is
96 * enough log space for all outstanding operations, we need to limit the
97 * number of outstanding buffers possible at any time. When the
98 * operation completes, any buffer credits not used are credited back to
99 * the transaction, so that at all times we know how many buffers the
100 * outstanding updates on a transaction might possibly touch.
102 * This is an opaque datatype.
104 typedef struct handle_s handle_t; /* Atomic operation type */
108 * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem.
110 * journal_t is linked to from the fs superblock structure.
112 * We use the journal_t to keep track of all outstanding transaction
113 * activity on the filesystem, and to manage the state of the log
116 * This is an opaque datatype.
118 typedef struct journal_s journal_t; /* Journal control structure */
122 * Internal structures used by the logging mechanism:
125 #define JBD2_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */
132 * Descriptor block types:
135 #define JBD2_DESCRIPTOR_BLOCK 1
136 #define JBD2_COMMIT_BLOCK 2
137 #define JBD2_SUPERBLOCK_V1 3
138 #define JBD2_SUPERBLOCK_V2 4
139 #define JBD2_REVOKE_BLOCK 5
142 * Standard header for all descriptor blocks:
144 typedef struct journal_header_s
153 * The block tag: used to describe a single buffer in the journal.
154 * t_blocknr_high is only used if INCOMPAT_64BIT is set, so this
155 * raw struct shouldn't be used for pointer math or sizeof() - use
156 * journal_tag_bytes(journal) instead to compute this.
158 typedef struct journal_block_tag_s
160 __be32 t_blocknr; /* The on-disk block number */
161 __be32 t_flags; /* See below */
162 __be32 t_blocknr_high; /* most-significant high 32bits. */
163 } journal_block_tag_t;
165 #define JBD_TAG_SIZE32 (offsetof(journal_block_tag_t, t_blocknr_high))
166 #define JBD_TAG_SIZE64 (sizeof(journal_block_tag_t))
169 * The revoke descriptor: used on disk to describe a series of blocks to
170 * be revoked from the log
172 typedef struct jbd2_journal_revoke_header_s
174 journal_header_t r_header;
175 __be32 r_count; /* Count of bytes used in the block */
176 } jbd2_journal_revoke_header_t;
179 /* Definitions for the journal tag flags word: */
180 #define JBD2_FLAG_ESCAPE 1 /* on-disk block is escaped */
181 #define JBD2_FLAG_SAME_UUID 2 /* block has same uuid as previous */
182 #define JBD2_FLAG_DELETED 4 /* block deleted by this transaction */
183 #define JBD2_FLAG_LAST_TAG 8 /* last tag in this descriptor block */
187 * The journal superblock. All fields are in big-endian byte order.
189 typedef struct journal_superblock_s
192 journal_header_t s_header;
195 /* Static information describing the journal */
196 __be32 s_blocksize; /* journal device blocksize */
197 __be32 s_maxlen; /* total blocks in journal file */
198 __be32 s_first; /* first block of log information */
201 /* Dynamic information describing the current state of the log */
202 __be32 s_sequence; /* first commit ID expected in log */
203 __be32 s_start; /* blocknr of start of log */
206 /* Error value, as set by jbd2_journal_abort(). */
210 /* Remaining fields are only valid in a version-2 superblock */
211 __be32 s_feature_compat; /* compatible feature set */
212 __be32 s_feature_incompat; /* incompatible feature set */
213 __be32 s_feature_ro_compat; /* readonly-compatible feature set */
215 __u8 s_uuid[16]; /* 128-bit uuid for journal */
218 __be32 s_nr_users; /* Nr of filesystems sharing log */
220 __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/
223 __be32 s_max_transaction; /* Limit of journal blocks per trans.*/
224 __be32 s_max_trans_data; /* Limit of data blocks per trans. */
230 __u8 s_users[16*48]; /* ids of all fs'es sharing the log */
232 } journal_superblock_t;
234 #define JBD2_HAS_COMPAT_FEATURE(j,mask) \
235 ((j)->j_format_version >= 2 && \
236 ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask))))
237 #define JBD2_HAS_RO_COMPAT_FEATURE(j,mask) \
238 ((j)->j_format_version >= 2 && \
239 ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask))))
240 #define JBD2_HAS_INCOMPAT_FEATURE(j,mask) \
241 ((j)->j_format_version >= 2 && \
242 ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask))))
244 #define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001
245 #define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002
247 /* Features known to this kernel version: */
248 #define JBD2_KNOWN_COMPAT_FEATURES 0
249 #define JBD2_KNOWN_ROCOMPAT_FEATURES 0
250 #define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \
251 JBD2_FEATURE_INCOMPAT_64BIT)
255 #include <linux/fs.h>
256 #include <linux/sched.h>
258 #define JBD_ASSERTIONS
259 #ifdef JBD_ASSERTIONS
260 #define J_ASSERT(assert) \
264 "Assertion failure in %s() at %s:%d: \"%s\"\n", \
265 __FUNCTION__, __FILE__, __LINE__, # assert); \
270 #if defined(CONFIG_BUFFER_DEBUG)
271 void buffer_assertion_failure(struct buffer_head *bh);
272 #define J_ASSERT_BH(bh, expr) \
275 buffer_assertion_failure(bh); \
278 #define J_ASSERT_JH(jh, expr) J_ASSERT_BH(jh2bh(jh), expr)
280 #define J_ASSERT_BH(bh, expr) J_ASSERT(expr)
281 #define J_ASSERT_JH(jh, expr) J_ASSERT(expr)
285 #define J_ASSERT(assert) do { } while (0)
286 #endif /* JBD_ASSERTIONS */
288 #if defined(JBD_PARANOID_IOFAIL)
289 #define J_EXPECT(expr, why...) J_ASSERT(expr)
290 #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr)
291 #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr)
293 #define __journal_expect(expr, why...) \
298 "EXT3-fs unexpected failure: %s;\n",# expr); \
299 printk(KERN_ERR why "\n"); \
303 #define J_EXPECT(expr, why...) __journal_expect(expr, ## why)
304 #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why)
305 #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why)
308 enum jbd_state_bits {
309 BH_JBD /* Has an attached ext3 journal_head */
311 BH_JWrite, /* Being written to log (@@@ DEBUGGING) */
312 BH_Freed, /* Has been freed (truncated) */
313 BH_Revoked, /* Has been revoked from the log */
314 BH_RevokeValid, /* Revoked flag is valid */
315 BH_JBDDirty, /* Is dirty but journaled */
316 BH_State, /* Pins most journal_head state */
317 BH_JournalHead, /* Pins bh->b_private and jh->b_bh */
318 BH_Unshadow, /* Dummy bit, for BJ_Shadow wakeup filtering */
322 BUFFER_FNS(JWrite, jwrite)
323 BUFFER_FNS(JBDDirty, jbddirty)
324 TAS_BUFFER_FNS(JBDDirty, jbddirty)
325 BUFFER_FNS(Revoked, revoked)
326 TAS_BUFFER_FNS(Revoked, revoked)
327 BUFFER_FNS(RevokeValid, revokevalid)
328 TAS_BUFFER_FNS(RevokeValid, revokevalid)
329 BUFFER_FNS(Freed, freed)
331 static inline struct buffer_head *jh2bh(struct journal_head *jh)
336 static inline struct journal_head *bh2jh(struct buffer_head *bh)
338 return bh->b_private;
341 static inline void jbd_lock_bh_state(struct buffer_head *bh)
343 bit_spin_lock(BH_State, &bh->b_state);
346 static inline int jbd_trylock_bh_state(struct buffer_head *bh)
348 return bit_spin_trylock(BH_State, &bh->b_state);
351 static inline int jbd_is_locked_bh_state(struct buffer_head *bh)
353 return bit_spin_is_locked(BH_State, &bh->b_state);
356 static inline void jbd_unlock_bh_state(struct buffer_head *bh)
358 bit_spin_unlock(BH_State, &bh->b_state);
361 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh)
363 bit_spin_lock(BH_JournalHead, &bh->b_state);
366 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
368 bit_spin_unlock(BH_JournalHead, &bh->b_state);
371 struct jbd2_revoke_table_s;
374 * struct handle_s - The handle_s type is the concrete type associated with
376 * @h_transaction: Which compound transaction is this update a part of?
377 * @h_buffer_credits: Number of remaining buffers we are allowed to dirty.
378 * @h_ref: Reference count on this handle
379 * @h_err: Field for caller's use to track errors through large fs operations
380 * @h_sync: flag for sync-on-close
381 * @h_jdata: flag to force data journaling
382 * @h_aborted: flag indicating fatal error on handle
385 /* Docbook can't yet cope with the bit fields, but will leave the documentation
386 * in so it can be fixed later.
391 /* Which compound transaction is this update a part of? */
392 transaction_t *h_transaction;
394 /* Number of remaining buffers we are allowed to dirty: */
395 int h_buffer_credits;
397 /* Reference count on this handle */
400 /* Field for caller's use to track errors through large fs */
404 /* Flags [no locking] */
405 unsigned int h_sync: 1; /* sync-on-close */
406 unsigned int h_jdata: 1; /* force data journaling */
407 unsigned int h_aborted: 1; /* fatal error on handle */
411 /* The transaction_t type is the guts of the journaling mechanism. It
412 * tracks a compound transaction through its various states:
414 * RUNNING: accepting new updates
415 * LOCKED: Updates still running but we don't accept new ones
416 * RUNDOWN: Updates are tidying up but have finished requesting
417 * new buffers to modify (state not used for now)
418 * FLUSH: All updates complete, but we are still writing to disk
419 * COMMIT: All data on disk, writing commit record
420 * FINISHED: We still have to keep the transaction for checkpointing.
422 * The transaction keeps track of all of the buffers modified by a
423 * running transaction, and all of the buffers committed but not yet
424 * flushed to home for finished transactions.
431 * ->jbd_lock_bh_journal_head() (This is "innermost")
434 * ->jbd_lock_bh_state()
436 * jbd_lock_bh_state()
443 * ->j_list_lock (journal_unmap_buffer)
449 /* Pointer to the journal for this transaction. [no locking] */
450 journal_t *t_journal;
452 /* Sequence number for this transaction [no locking] */
456 * Transaction's current state
457 * [no locking - only kjournald2 alters this]
458 * FIXME: needs barriers
459 * KLUDGE: [use j_state_lock]
471 * Where in the log does this transaction's commit start? [no locking]
473 unsigned long t_log_start;
475 /* Number of buffers on the t_buffers list [j_list_lock] */
479 * Doubly-linked circular list of all buffers reserved but not yet
480 * modified by this transaction [j_list_lock]
482 struct journal_head *t_reserved_list;
485 * Doubly-linked circular list of all buffers under writeout during
486 * commit [j_list_lock]
488 struct journal_head *t_locked_list;
491 * Doubly-linked circular list of all metadata buffers owned by this
492 * transaction [j_list_lock]
494 struct journal_head *t_buffers;
497 * Doubly-linked circular list of all data buffers still to be
498 * flushed before this transaction can be committed [j_list_lock]
500 struct journal_head *t_sync_datalist;
503 * Doubly-linked circular list of all forget buffers (superseded
504 * buffers which we can un-checkpoint once this transaction commits)
507 struct journal_head *t_forget;
510 * Doubly-linked circular list of all buffers still to be flushed before
511 * this transaction can be checkpointed. [j_list_lock]
513 struct journal_head *t_checkpoint_list;
516 * Doubly-linked circular list of all buffers submitted for IO while
517 * checkpointing. [j_list_lock]
519 struct journal_head *t_checkpoint_io_list;
522 * Doubly-linked circular list of temporary buffers currently undergoing
523 * IO in the log [j_list_lock]
525 struct journal_head *t_iobuf_list;
528 * Doubly-linked circular list of metadata buffers being shadowed by log
529 * IO. The IO buffers on the iobuf list and the shadow buffers on this
530 * list match each other one for one at all times. [j_list_lock]
532 struct journal_head *t_shadow_list;
535 * Doubly-linked circular list of control buffers being written to the
538 struct journal_head *t_log_list;
541 * Protects info related to handles
543 spinlock_t t_handle_lock;
546 * Number of outstanding updates running on this transaction
552 * Number of buffers reserved for use by all handles in this transaction
553 * handle but not yet modified. [t_handle_lock]
555 int t_outstanding_credits;
558 * Forward and backward links for the circular list of all transactions
559 * awaiting checkpoint. [j_list_lock]
561 transaction_t *t_cpnext, *t_cpprev;
564 * When will the transaction expire (become due for commit), in jiffies?
567 unsigned long t_expires;
570 * How many handles used this transaction? [t_handle_lock]
577 * struct journal_s - The journal_s type is the concrete type associated with
579 * @j_flags: General journaling state flags
580 * @j_errno: Is there an outstanding uncleared error on the journal (from a
582 * @j_sb_buffer: First part of superblock buffer
583 * @j_superblock: Second part of superblock buffer
584 * @j_format_version: Version of the superblock format
585 * @j_state_lock: Protect the various scalars in the journal
586 * @j_barrier_count: Number of processes waiting to create a barrier lock
587 * @j_barrier: The barrier lock itself
588 * @j_running_transaction: The current running transaction..
589 * @j_committing_transaction: the transaction we are pushing to disk
590 * @j_checkpoint_transactions: a linked circular list of all transactions
591 * waiting for checkpointing
592 * @j_wait_transaction_locked: Wait queue for waiting for a locked transaction
593 * to start committing, or for a barrier lock to be released
594 * @j_wait_logspace: Wait queue for waiting for checkpointing to complete
595 * @j_wait_done_commit: Wait queue for waiting for commit to complete
596 * @j_wait_checkpoint: Wait queue to trigger checkpointing
597 * @j_wait_commit: Wait queue to trigger commit
598 * @j_wait_updates: Wait queue to wait for updates to complete
599 * @j_checkpoint_mutex: Mutex for locking against concurrent checkpoints
600 * @j_head: Journal head - identifies the first unused block in the journal
601 * @j_tail: Journal tail - identifies the oldest still-used block in the
603 * @j_free: Journal free - how many free blocks are there in the journal?
604 * @j_first: The block number of the first usable block
605 * @j_last: The block number one beyond the last usable block
606 * @j_dev: Device where we store the journal
607 * @j_blocksize: blocksize for the location where we store the journal.
608 * @j_blk_offset: starting block offset for into the device where we store the
610 * @j_fs_dev: Device which holds the client fs. For internal journal this will
612 * @j_maxlen: Total maximum capacity of the journal region on disk.
613 * @j_list_lock: Protects the buffer lists and internal buffer state.
614 * @j_inode: Optional inode where we store the journal. If present, all journal
615 * block numbers are mapped into this inode via bmap().
616 * @j_tail_sequence: Sequence number of the oldest transaction in the log
617 * @j_transaction_sequence: Sequence number of the next transaction to grant
618 * @j_commit_sequence: Sequence number of the most recently committed
620 * @j_commit_request: Sequence number of the most recent transaction wanting
622 * @j_uuid: Uuid of client object.
623 * @j_task: Pointer to the current commit thread for this journal
624 * @j_max_transaction_buffers: Maximum number of metadata buffers to allow in a
625 * single compound commit transaction
626 * @j_commit_interval: What is the maximum transaction lifetime before we begin
628 * @j_commit_timer: The timer used to wakeup the commit thread
629 * @j_revoke_lock: Protect the revoke table
630 * @j_revoke: The revoke table - maintains the list of revoked blocks in the
631 * current transaction.
632 * @j_revoke_table: alternate revoke tables for j_revoke
633 * @j_wbuf: array of buffer_heads for jbd2_journal_commit_transaction
634 * @j_wbufsize: maximum number of buffer_heads allowed in j_wbuf, the
635 * number that will fit in j_blocksize
636 * @j_last_sync_writer: most recent pid which did a synchronous write
637 * @j_private: An opaque pointer to fs-private information.
642 /* General journaling state flags [j_state_lock] */
643 unsigned long j_flags;
646 * Is there an outstanding uncleared error on the journal (from a prior
647 * abort)? [j_state_lock]
651 /* The superblock buffer */
652 struct buffer_head *j_sb_buffer;
653 journal_superblock_t *j_superblock;
655 /* Version of the superblock format */
656 int j_format_version;
659 * Protect the various scalars in the journal
661 spinlock_t j_state_lock;
664 * Number of processes waiting to create a barrier lock [j_state_lock]
668 /* The barrier lock itself */
669 struct mutex j_barrier;
672 * Transactions: The current running transaction...
673 * [j_state_lock] [caller holding open handle]
675 transaction_t *j_running_transaction;
678 * the transaction we are pushing to disk
679 * [j_state_lock] [caller holding open handle]
681 transaction_t *j_committing_transaction;
684 * ... and a linked circular list of all transactions waiting for
685 * checkpointing. [j_list_lock]
687 transaction_t *j_checkpoint_transactions;
690 * Wait queue for waiting for a locked transaction to start committing,
691 * or for a barrier lock to be released
693 wait_queue_head_t j_wait_transaction_locked;
695 /* Wait queue for waiting for checkpointing to complete */
696 wait_queue_head_t j_wait_logspace;
698 /* Wait queue for waiting for commit to complete */
699 wait_queue_head_t j_wait_done_commit;
701 /* Wait queue to trigger checkpointing */
702 wait_queue_head_t j_wait_checkpoint;
704 /* Wait queue to trigger commit */
705 wait_queue_head_t j_wait_commit;
707 /* Wait queue to wait for updates to complete */
708 wait_queue_head_t j_wait_updates;
710 /* Semaphore for locking against concurrent checkpoints */
711 struct mutex j_checkpoint_mutex;
714 * Journal head: identifies the first unused block in the journal.
717 unsigned long j_head;
720 * Journal tail: identifies the oldest still-used block in the journal.
723 unsigned long j_tail;
726 * Journal free: how many free blocks are there in the journal?
729 unsigned long j_free;
732 * Journal start and end: the block numbers of the first usable block
733 * and one beyond the last usable block in the journal. [j_state_lock]
735 unsigned long j_first;
736 unsigned long j_last;
739 * Device, blocksize and starting block offset for the location where we
742 struct block_device *j_dev;
744 unsigned long j_blk_offset;
747 * Device which holds the client fs. For internal journal this will be
750 struct block_device *j_fs_dev;
752 /* Total maximum capacity of the journal region on disk. */
753 unsigned int j_maxlen;
756 * Protects the buffer lists and internal buffer state.
758 spinlock_t j_list_lock;
760 /* Optional inode where we store the journal. If present, all */
761 /* journal block numbers are mapped into this inode via */
763 struct inode *j_inode;
766 * Sequence number of the oldest transaction in the log [j_state_lock]
768 tid_t j_tail_sequence;
771 * Sequence number of the next transaction to grant [j_state_lock]
773 tid_t j_transaction_sequence;
776 * Sequence number of the most recently committed transaction
779 tid_t j_commit_sequence;
782 * Sequence number of the most recent transaction wanting commit
785 tid_t j_commit_request;
788 * Journal uuid: identifies the object (filesystem, LVM volume etc)
789 * backed by this journal. This will eventually be replaced by an array
790 * of uuids, allowing us to index multiple devices within a single
791 * journal and to perform atomic updates across them.
795 /* Pointer to the current commit thread for this journal */
796 struct task_struct *j_task;
799 * Maximum number of metadata buffers to allow in a single compound
802 int j_max_transaction_buffers;
805 * What is the maximum transaction lifetime before we begin a commit?
807 unsigned long j_commit_interval;
809 /* The timer used to wakeup the commit thread: */
810 struct timer_list j_commit_timer;
813 * The revoke table: maintains the list of revoked blocks in the
814 * current transaction. [j_revoke_lock]
816 spinlock_t j_revoke_lock;
817 struct jbd2_revoke_table_s *j_revoke;
818 struct jbd2_revoke_table_s *j_revoke_table[2];
821 * array of bhs for jbd2_journal_commit_transaction
823 struct buffer_head **j_wbuf;
826 pid_t j_last_sync_writer;
829 * An opaque pointer to fs-private information. ext3 puts its
830 * superblock pointer here
836 * Journal flag definitions
838 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */
839 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */
840 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */
841 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */
842 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */
843 #define JBD2_BARRIER 0x020 /* Use IDE barriers */
846 * Function declarations for the journaling transaction and buffer
851 extern void __jbd2_journal_temp_unlink_buffer(struct journal_head *jh);
852 extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *);
853 extern void __jbd2_journal_unfile_buffer(struct journal_head *);
854 extern void __jbd2_journal_refile_buffer(struct journal_head *);
855 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *);
856 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
857 extern void __journal_free_buffer(struct journal_head *bh);
858 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
859 extern void __journal_clean_data_list(transaction_t *transaction);
861 /* Log buffer allocation */
862 extern struct journal_head * jbd2_journal_get_descriptor_buffer(journal_t *);
863 int jbd2_journal_next_log_block(journal_t *, unsigned long *);
865 /* Commit management */
866 extern void jbd2_journal_commit_transaction(journal_t *);
868 /* Checkpoint list management */
869 int __jbd2_journal_clean_checkpoint_list(journal_t *journal);
870 int __jbd2_journal_remove_checkpoint(struct journal_head *);
871 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *);
875 jbd2_journal_write_metadata_buffer(transaction_t *transaction,
876 struct journal_head *jh_in,
877 struct journal_head **jh_out,
878 unsigned long blocknr);
880 /* Transaction locking */
881 extern void __wait_on_journal (journal_t *);
886 * We need to lock the journal during transaction state changes so that nobody
887 * ever tries to take a handle on the running transaction while we are in the
888 * middle of moving it to the commit phase. j_state_lock does this.
890 * Note that the locking is completely interrupt unsafe. We never touch
891 * journal structures from interrupts.
894 static inline handle_t *journal_current_handle(void)
896 return current->journal_info;
899 /* The journaling code user interface:
901 * Create and destroy handles
902 * Register buffer modifications against the current transaction.
905 extern handle_t *jbd2_journal_start(journal_t *, int nblocks);
906 extern int jbd2_journal_restart (handle_t *, int nblocks);
907 extern int jbd2_journal_extend (handle_t *, int nblocks);
908 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *);
909 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *);
910 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *);
911 extern int jbd2_journal_dirty_data (handle_t *, struct buffer_head *);
912 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *);
913 extern void jbd2_journal_release_buffer (handle_t *, struct buffer_head *);
914 extern int jbd2_journal_forget (handle_t *, struct buffer_head *);
915 extern void journal_sync_buffer (struct buffer_head *);
916 extern void jbd2_journal_invalidatepage(journal_t *,
917 struct page *, unsigned long);
918 extern int jbd2_journal_try_to_free_buffers(journal_t *, struct page *, gfp_t);
919 extern int jbd2_journal_stop(handle_t *);
920 extern int jbd2_journal_flush (journal_t *);
921 extern void jbd2_journal_lock_updates (journal_t *);
922 extern void jbd2_journal_unlock_updates (journal_t *);
924 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev,
925 struct block_device *fs_dev,
926 int start, int len, int bsize);
927 extern journal_t * jbd2_journal_init_inode (struct inode *);
928 extern int jbd2_journal_update_format (journal_t *);
929 extern int jbd2_journal_check_used_features
930 (journal_t *, unsigned long, unsigned long, unsigned long);
931 extern int jbd2_journal_check_available_features
932 (journal_t *, unsigned long, unsigned long, unsigned long);
933 extern int jbd2_journal_set_features
934 (journal_t *, unsigned long, unsigned long, unsigned long);
935 extern int jbd2_journal_create (journal_t *);
936 extern int jbd2_journal_load (journal_t *journal);
937 extern void jbd2_journal_destroy (journal_t *);
938 extern int jbd2_journal_recover (journal_t *journal);
939 extern int jbd2_journal_wipe (journal_t *, int);
940 extern int jbd2_journal_skip_recovery (journal_t *);
941 extern void jbd2_journal_update_superblock (journal_t *, int);
942 extern void __jbd2_journal_abort_hard (journal_t *);
943 extern void jbd2_journal_abort (journal_t *, int);
944 extern int jbd2_journal_errno (journal_t *);
945 extern void jbd2_journal_ack_err (journal_t *);
946 extern int jbd2_journal_clear_err (journal_t *);
947 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long *);
948 extern int jbd2_journal_force_commit(journal_t *);
951 * journal_head management
953 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh);
954 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh);
955 void jbd2_journal_remove_journal_head(struct buffer_head *bh);
956 void jbd2_journal_put_journal_head(struct journal_head *jh);
961 extern kmem_cache_t *jbd2_handle_cache;
963 static inline handle_t *jbd_alloc_handle(gfp_t gfp_flags)
965 return kmem_cache_alloc(jbd2_handle_cache, gfp_flags);
968 static inline void jbd_free_handle(handle_t *handle)
970 kmem_cache_free(jbd2_handle_cache, handle);
973 /* Primary revoke support */
974 #define JOURNAL_REVOKE_DEFAULT_HASH 256
975 extern int jbd2_journal_init_revoke(journal_t *, int);
976 extern void jbd2_journal_destroy_revoke_caches(void);
977 extern int jbd2_journal_init_revoke_caches(void);
979 extern void jbd2_journal_destroy_revoke(journal_t *);
980 extern int jbd2_journal_revoke (handle_t *,
981 unsigned long, struct buffer_head *);
982 extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *);
983 extern void jbd2_journal_write_revoke_records(journal_t *, transaction_t *);
985 /* Recovery revoke support */
986 extern int jbd2_journal_set_revoke(journal_t *, unsigned long, tid_t);
987 extern int jbd2_journal_test_revoke(journal_t *, unsigned long, tid_t);
988 extern void jbd2_journal_clear_revoke(journal_t *);
989 extern void jbd2_journal_switch_revoke_table(journal_t *journal);
992 * The log thread user interface:
994 * Request space in the current transaction, and force transaction commit
995 * transitions on demand.
998 int __jbd2_log_space_left(journal_t *); /* Called with journal locked */
999 int jbd2_log_start_commit(journal_t *journal, tid_t tid);
1000 int __jbd2_log_start_commit(journal_t *journal, tid_t tid);
1001 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid);
1002 int jbd2_journal_force_commit_nested(journal_t *journal);
1003 int jbd2_log_wait_commit(journal_t *journal, tid_t tid);
1004 int jbd2_log_do_checkpoint(journal_t *journal);
1006 void __jbd2_log_wait_for_space(journal_t *journal);
1007 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *);
1008 extern int jbd2_cleanup_journal_tail(journal_t *);
1010 /* Debugging code only: */
1012 #define jbd_ENOSYS() \
1014 printk (KERN_ERR "JBD unimplemented function %s\n", __FUNCTION__); \
1015 current->state = TASK_UNINTERRUPTIBLE; \
1022 * Simple test wrapper function to test the JBD2_ABORT state flag. This
1023 * bit, when set, indicates that we have had a fatal error somewhere,
1024 * either inside the journaling layer or indicated to us by the client
1025 * (eg. ext3), and that we and should not commit any further
1029 static inline int is_journal_aborted(journal_t *journal)
1031 return journal->j_flags & JBD2_ABORT;
1034 static inline int is_handle_aborted(handle_t *handle)
1036 if (handle->h_aborted)
1038 return is_journal_aborted(handle->h_transaction->t_journal);
1041 static inline void jbd2_journal_abort_handle(handle_t *handle)
1043 handle->h_aborted = 1;
1046 #endif /* __KERNEL__ */
1048 /* Comparison functions for transaction IDs: perform comparisons using
1049 * modulo arithmetic so that they work over sequence number wraps. */
1051 static inline int tid_gt(tid_t x, tid_t y)
1053 int difference = (x - y);
1054 return (difference > 0);
1057 static inline int tid_geq(tid_t x, tid_t y)
1059 int difference = (x - y);
1060 return (difference >= 0);
1063 extern int jbd2_journal_blocks_per_page(struct inode *inode);
1064 extern size_t journal_tag_bytes(journal_t *journal);
1067 * Return the minimum number of blocks which must be free in the journal
1068 * before a new transaction may be started. Must be called under j_state_lock.
1070 static inline int jbd_space_needed(journal_t *journal)
1072 int nblocks = journal->j_max_transaction_buffers;
1073 if (journal->j_committing_transaction)
1074 nblocks += journal->j_committing_transaction->
1075 t_outstanding_credits;
1080 * Definitions which augment the buffer_head layer
1083 /* journaling buffer types */
1084 #define BJ_None 0 /* Not journaled */
1085 #define BJ_SyncData 1 /* Normal data: flush before commit */
1086 #define BJ_Metadata 2 /* Normal journaled metadata */
1087 #define BJ_Forget 3 /* Buffer superseded by this transaction */
1088 #define BJ_IO 4 /* Buffer is for temporary IO use */
1089 #define BJ_Shadow 5 /* Buffer contents being shadowed to the log */
1090 #define BJ_LogCtl 6 /* Buffer contains log descriptors */
1091 #define BJ_Reserved 7 /* Buffer is reserved for access by journal */
1092 #define BJ_Locked 8 /* Locked for I/O during commit */
1095 extern int jbd_blocks_per_page(struct inode *inode);
1099 #define buffer_trace_init(bh) do {} while (0)
1100 #define print_buffer_fields(bh) do {} while (0)
1101 #define print_buffer_trace(bh) do {} while (0)
1102 #define BUFFER_TRACE(bh, info) do {} while (0)
1103 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0)
1104 #define JBUFFER_TRACE(jh, info) do {} while (0)
1106 #endif /* __KERNEL__ */
1108 #endif /* _LINUX_JBD_H */