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_JBD2_DEBUG
55 * Define JBD_EXPENSIVE_CHECKING to enable more expensive internal
56 * consistency checks. By default we don't do this unless
57 * CONFIG_JBD2_DEBUG is on.
59 #define JBD_EXPENSIVE_CHECKING
60 extern u8 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 #define jbd_kmalloc(size, flags) \
76 __jbd2_kmalloc(__FUNCTION__, (size), (flags), journal_oom_retry)
77 #define jbd_rep_kmalloc(size, flags) \
78 __jbd2_kmalloc(__FUNCTION__, (size), (flags), 1)
81 static inline void *jbd2_alloc(size_t size, gfp_t flags)
83 return (void *)__get_free_pages(flags, get_order(size));
86 static inline void jbd2_free(void *ptr, size_t size)
88 free_pages((unsigned long)ptr, get_order(size));
91 #define JBD2_MIN_JOURNAL_BLOCKS 1024
96 * typedef handle_t - The handle_t type represents a single atomic update being performed by some process.
98 * All filesystem modifications made by the process go
99 * through this handle. Recursive operations (such as quota operations)
100 * are gathered into a single update.
102 * The buffer credits field is used to account for journaled buffers
103 * being modified by the running process. To ensure that there is
104 * enough log space for all outstanding operations, we need to limit the
105 * number of outstanding buffers possible at any time. When the
106 * operation completes, any buffer credits not used are credited back to
107 * the transaction, so that at all times we know how many buffers the
108 * outstanding updates on a transaction might possibly touch.
110 * This is an opaque datatype.
112 typedef struct handle_s handle_t; /* Atomic operation type */
116 * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem.
118 * journal_t is linked to from the fs superblock structure.
120 * We use the journal_t to keep track of all outstanding transaction
121 * activity on the filesystem, and to manage the state of the log
124 * This is an opaque datatype.
126 typedef struct journal_s journal_t; /* Journal control structure */
130 * Internal structures used by the logging mechanism:
133 #define JBD2_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */
140 * Descriptor block types:
143 #define JBD2_DESCRIPTOR_BLOCK 1
144 #define JBD2_COMMIT_BLOCK 2
145 #define JBD2_SUPERBLOCK_V1 3
146 #define JBD2_SUPERBLOCK_V2 4
147 #define JBD2_REVOKE_BLOCK 5
150 * Standard header for all descriptor blocks:
152 typedef struct journal_header_s
161 * The block tag: used to describe a single buffer in the journal.
162 * t_blocknr_high is only used if INCOMPAT_64BIT is set, so this
163 * raw struct shouldn't be used for pointer math or sizeof() - use
164 * journal_tag_bytes(journal) instead to compute this.
166 typedef struct journal_block_tag_s
168 __be32 t_blocknr; /* The on-disk block number */
169 __be32 t_flags; /* See below */
170 __be32 t_blocknr_high; /* most-significant high 32bits. */
171 } journal_block_tag_t;
173 #define JBD_TAG_SIZE32 (offsetof(journal_block_tag_t, t_blocknr_high))
174 #define JBD_TAG_SIZE64 (sizeof(journal_block_tag_t))
177 * The revoke descriptor: used on disk to describe a series of blocks to
178 * be revoked from the log
180 typedef struct jbd2_journal_revoke_header_s
182 journal_header_t r_header;
183 __be32 r_count; /* Count of bytes used in the block */
184 } jbd2_journal_revoke_header_t;
187 /* Definitions for the journal tag flags word: */
188 #define JBD2_FLAG_ESCAPE 1 /* on-disk block is escaped */
189 #define JBD2_FLAG_SAME_UUID 2 /* block has same uuid as previous */
190 #define JBD2_FLAG_DELETED 4 /* block deleted by this transaction */
191 #define JBD2_FLAG_LAST_TAG 8 /* last tag in this descriptor block */
195 * The journal superblock. All fields are in big-endian byte order.
197 typedef struct journal_superblock_s
200 journal_header_t s_header;
203 /* Static information describing the journal */
204 __be32 s_blocksize; /* journal device blocksize */
205 __be32 s_maxlen; /* total blocks in journal file */
206 __be32 s_first; /* first block of log information */
209 /* Dynamic information describing the current state of the log */
210 __be32 s_sequence; /* first commit ID expected in log */
211 __be32 s_start; /* blocknr of start of log */
214 /* Error value, as set by jbd2_journal_abort(). */
218 /* Remaining fields are only valid in a version-2 superblock */
219 __be32 s_feature_compat; /* compatible feature set */
220 __be32 s_feature_incompat; /* incompatible feature set */
221 __be32 s_feature_ro_compat; /* readonly-compatible feature set */
223 __u8 s_uuid[16]; /* 128-bit uuid for journal */
226 __be32 s_nr_users; /* Nr of filesystems sharing log */
228 __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/
231 __be32 s_max_transaction; /* Limit of journal blocks per trans.*/
232 __be32 s_max_trans_data; /* Limit of data blocks per trans. */
238 __u8 s_users[16*48]; /* ids of all fs'es sharing the log */
240 } journal_superblock_t;
242 #define JBD2_HAS_COMPAT_FEATURE(j,mask) \
243 ((j)->j_format_version >= 2 && \
244 ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask))))
245 #define JBD2_HAS_RO_COMPAT_FEATURE(j,mask) \
246 ((j)->j_format_version >= 2 && \
247 ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask))))
248 #define JBD2_HAS_INCOMPAT_FEATURE(j,mask) \
249 ((j)->j_format_version >= 2 && \
250 ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask))))
252 #define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001
253 #define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002
255 /* Features known to this kernel version: */
256 #define JBD2_KNOWN_COMPAT_FEATURES 0
257 #define JBD2_KNOWN_ROCOMPAT_FEATURES 0
258 #define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \
259 JBD2_FEATURE_INCOMPAT_64BIT)
263 #include <linux/fs.h>
264 #include <linux/sched.h>
266 #define JBD_ASSERTIONS
267 #ifdef JBD_ASSERTIONS
268 #define J_ASSERT(assert) \
272 "Assertion failure in %s() at %s:%d: \"%s\"\n", \
273 __FUNCTION__, __FILE__, __LINE__, # assert); \
278 #if defined(CONFIG_BUFFER_DEBUG)
279 void buffer_assertion_failure(struct buffer_head *bh);
280 #define J_ASSERT_BH(bh, expr) \
283 buffer_assertion_failure(bh); \
286 #define J_ASSERT_JH(jh, expr) J_ASSERT_BH(jh2bh(jh), expr)
288 #define J_ASSERT_BH(bh, expr) J_ASSERT(expr)
289 #define J_ASSERT_JH(jh, expr) J_ASSERT(expr)
293 #define J_ASSERT(assert) do { } while (0)
294 #endif /* JBD_ASSERTIONS */
296 #if defined(JBD_PARANOID_IOFAIL)
297 #define J_EXPECT(expr, why...) J_ASSERT(expr)
298 #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr)
299 #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr)
301 #define __journal_expect(expr, why...) \
306 "EXT3-fs unexpected failure: %s;\n",# expr); \
307 printk(KERN_ERR why "\n"); \
311 #define J_EXPECT(expr, why...) __journal_expect(expr, ## why)
312 #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why)
313 #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why)
316 enum jbd_state_bits {
317 BH_JBD /* Has an attached ext3 journal_head */
319 BH_JWrite, /* Being written to log (@@@ DEBUGGING) */
320 BH_Freed, /* Has been freed (truncated) */
321 BH_Revoked, /* Has been revoked from the log */
322 BH_RevokeValid, /* Revoked flag is valid */
323 BH_JBDDirty, /* Is dirty but journaled */
324 BH_State, /* Pins most journal_head state */
325 BH_JournalHead, /* Pins bh->b_private and jh->b_bh */
326 BH_Unshadow, /* Dummy bit, for BJ_Shadow wakeup filtering */
330 BUFFER_FNS(JWrite, jwrite)
331 BUFFER_FNS(JBDDirty, jbddirty)
332 TAS_BUFFER_FNS(JBDDirty, jbddirty)
333 BUFFER_FNS(Revoked, revoked)
334 TAS_BUFFER_FNS(Revoked, revoked)
335 BUFFER_FNS(RevokeValid, revokevalid)
336 TAS_BUFFER_FNS(RevokeValid, revokevalid)
337 BUFFER_FNS(Freed, freed)
339 static inline struct buffer_head *jh2bh(struct journal_head *jh)
344 static inline struct journal_head *bh2jh(struct buffer_head *bh)
346 return bh->b_private;
349 static inline void jbd_lock_bh_state(struct buffer_head *bh)
351 bit_spin_lock(BH_State, &bh->b_state);
354 static inline int jbd_trylock_bh_state(struct buffer_head *bh)
356 return bit_spin_trylock(BH_State, &bh->b_state);
359 static inline int jbd_is_locked_bh_state(struct buffer_head *bh)
361 return bit_spin_is_locked(BH_State, &bh->b_state);
364 static inline void jbd_unlock_bh_state(struct buffer_head *bh)
366 bit_spin_unlock(BH_State, &bh->b_state);
369 static inline void jbd_lock_bh_journal_head(struct buffer_head *bh)
371 bit_spin_lock(BH_JournalHead, &bh->b_state);
374 static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
376 bit_spin_unlock(BH_JournalHead, &bh->b_state);
379 struct jbd2_revoke_table_s;
382 * struct handle_s - The handle_s type is the concrete type associated with
384 * @h_transaction: Which compound transaction is this update a part of?
385 * @h_buffer_credits: Number of remaining buffers we are allowed to dirty.
386 * @h_ref: Reference count on this handle
387 * @h_err: Field for caller's use to track errors through large fs operations
388 * @h_sync: flag for sync-on-close
389 * @h_jdata: flag to force data journaling
390 * @h_aborted: flag indicating fatal error on handle
393 /* Docbook can't yet cope with the bit fields, but will leave the documentation
394 * in so it can be fixed later.
399 /* Which compound transaction is this update a part of? */
400 transaction_t *h_transaction;
402 /* Number of remaining buffers we are allowed to dirty: */
403 int h_buffer_credits;
405 /* Reference count on this handle */
408 /* Field for caller's use to track errors through large fs */
412 /* Flags [no locking] */
413 unsigned int h_sync: 1; /* sync-on-close */
414 unsigned int h_jdata: 1; /* force data journaling */
415 unsigned int h_aborted: 1; /* fatal error on handle */
419 /* The transaction_t type is the guts of the journaling mechanism. It
420 * tracks a compound transaction through its various states:
422 * RUNNING: accepting new updates
423 * LOCKED: Updates still running but we don't accept new ones
424 * RUNDOWN: Updates are tidying up but have finished requesting
425 * new buffers to modify (state not used for now)
426 * FLUSH: All updates complete, but we are still writing to disk
427 * COMMIT: All data on disk, writing commit record
428 * FINISHED: We still have to keep the transaction for checkpointing.
430 * The transaction keeps track of all of the buffers modified by a
431 * running transaction, and all of the buffers committed but not yet
432 * flushed to home for finished transactions.
439 * ->jbd_lock_bh_journal_head() (This is "innermost")
442 * ->jbd_lock_bh_state()
444 * jbd_lock_bh_state()
451 * ->j_list_lock (journal_unmap_buffer)
457 /* Pointer to the journal for this transaction. [no locking] */
458 journal_t *t_journal;
460 /* Sequence number for this transaction [no locking] */
464 * Transaction's current state
465 * [no locking - only kjournald2 alters this]
466 * FIXME: needs barriers
467 * KLUDGE: [use j_state_lock]
479 * Where in the log does this transaction's commit start? [no locking]
481 unsigned long t_log_start;
483 /* Number of buffers on the t_buffers list [j_list_lock] */
487 * Doubly-linked circular list of all buffers reserved but not yet
488 * modified by this transaction [j_list_lock]
490 struct journal_head *t_reserved_list;
493 * Doubly-linked circular list of all buffers under writeout during
494 * commit [j_list_lock]
496 struct journal_head *t_locked_list;
499 * Doubly-linked circular list of all metadata buffers owned by this
500 * transaction [j_list_lock]
502 struct journal_head *t_buffers;
505 * Doubly-linked circular list of all data buffers still to be
506 * flushed before this transaction can be committed [j_list_lock]
508 struct journal_head *t_sync_datalist;
511 * Doubly-linked circular list of all forget buffers (superseded
512 * buffers which we can un-checkpoint once this transaction commits)
515 struct journal_head *t_forget;
518 * Doubly-linked circular list of all buffers still to be flushed before
519 * this transaction can be checkpointed. [j_list_lock]
521 struct journal_head *t_checkpoint_list;
524 * Doubly-linked circular list of all buffers submitted for IO while
525 * checkpointing. [j_list_lock]
527 struct journal_head *t_checkpoint_io_list;
530 * Doubly-linked circular list of temporary buffers currently undergoing
531 * IO in the log [j_list_lock]
533 struct journal_head *t_iobuf_list;
536 * Doubly-linked circular list of metadata buffers being shadowed by log
537 * IO. The IO buffers on the iobuf list and the shadow buffers on this
538 * list match each other one for one at all times. [j_list_lock]
540 struct journal_head *t_shadow_list;
543 * Doubly-linked circular list of control buffers being written to the
546 struct journal_head *t_log_list;
549 * Protects info related to handles
551 spinlock_t t_handle_lock;
554 * Number of outstanding updates running on this transaction
560 * Number of buffers reserved for use by all handles in this transaction
561 * handle but not yet modified. [t_handle_lock]
563 int t_outstanding_credits;
566 * Forward and backward links for the circular list of all transactions
567 * awaiting checkpoint. [j_list_lock]
569 transaction_t *t_cpnext, *t_cpprev;
572 * When will the transaction expire (become due for commit), in jiffies?
575 unsigned long t_expires;
578 * How many handles used this transaction? [t_handle_lock]
585 * struct journal_s - The journal_s type is the concrete type associated with
587 * @j_flags: General journaling state flags
588 * @j_errno: Is there an outstanding uncleared error on the journal (from a
590 * @j_sb_buffer: First part of superblock buffer
591 * @j_superblock: Second part of superblock buffer
592 * @j_format_version: Version of the superblock format
593 * @j_state_lock: Protect the various scalars in the journal
594 * @j_barrier_count: Number of processes waiting to create a barrier lock
595 * @j_barrier: The barrier lock itself
596 * @j_running_transaction: The current running transaction..
597 * @j_committing_transaction: the transaction we are pushing to disk
598 * @j_checkpoint_transactions: a linked circular list of all transactions
599 * waiting for checkpointing
600 * @j_wait_transaction_locked: Wait queue for waiting for a locked transaction
601 * to start committing, or for a barrier lock to be released
602 * @j_wait_logspace: Wait queue for waiting for checkpointing to complete
603 * @j_wait_done_commit: Wait queue for waiting for commit to complete
604 * @j_wait_checkpoint: Wait queue to trigger checkpointing
605 * @j_wait_commit: Wait queue to trigger commit
606 * @j_wait_updates: Wait queue to wait for updates to complete
607 * @j_checkpoint_mutex: Mutex for locking against concurrent checkpoints
608 * @j_head: Journal head - identifies the first unused block in the journal
609 * @j_tail: Journal tail - identifies the oldest still-used block in the
611 * @j_free: Journal free - how many free blocks are there in the journal?
612 * @j_first: The block number of the first usable block
613 * @j_last: The block number one beyond the last usable block
614 * @j_dev: Device where we store the journal
615 * @j_blocksize: blocksize for the location where we store the journal.
616 * @j_blk_offset: starting block offset for into the device where we store the
618 * @j_fs_dev: Device which holds the client fs. For internal journal this will
620 * @j_maxlen: Total maximum capacity of the journal region on disk.
621 * @j_list_lock: Protects the buffer lists and internal buffer state.
622 * @j_inode: Optional inode where we store the journal. If present, all journal
623 * block numbers are mapped into this inode via bmap().
624 * @j_tail_sequence: Sequence number of the oldest transaction in the log
625 * @j_transaction_sequence: Sequence number of the next transaction to grant
626 * @j_commit_sequence: Sequence number of the most recently committed
628 * @j_commit_request: Sequence number of the most recent transaction wanting
630 * @j_uuid: Uuid of client object.
631 * @j_task: Pointer to the current commit thread for this journal
632 * @j_max_transaction_buffers: Maximum number of metadata buffers to allow in a
633 * single compound commit transaction
634 * @j_commit_interval: What is the maximum transaction lifetime before we begin
636 * @j_commit_timer: The timer used to wakeup the commit thread
637 * @j_revoke_lock: Protect the revoke table
638 * @j_revoke: The revoke table - maintains the list of revoked blocks in the
639 * current transaction.
640 * @j_revoke_table: alternate revoke tables for j_revoke
641 * @j_wbuf: array of buffer_heads for jbd2_journal_commit_transaction
642 * @j_wbufsize: maximum number of buffer_heads allowed in j_wbuf, the
643 * number that will fit in j_blocksize
644 * @j_last_sync_writer: most recent pid which did a synchronous write
645 * @j_private: An opaque pointer to fs-private information.
650 /* General journaling state flags [j_state_lock] */
651 unsigned long j_flags;
654 * Is there an outstanding uncleared error on the journal (from a prior
655 * abort)? [j_state_lock]
659 /* The superblock buffer */
660 struct buffer_head *j_sb_buffer;
661 journal_superblock_t *j_superblock;
663 /* Version of the superblock format */
664 int j_format_version;
667 * Protect the various scalars in the journal
669 spinlock_t j_state_lock;
672 * Number of processes waiting to create a barrier lock [j_state_lock]
676 /* The barrier lock itself */
677 struct mutex j_barrier;
680 * Transactions: The current running transaction...
681 * [j_state_lock] [caller holding open handle]
683 transaction_t *j_running_transaction;
686 * the transaction we are pushing to disk
687 * [j_state_lock] [caller holding open handle]
689 transaction_t *j_committing_transaction;
692 * ... and a linked circular list of all transactions waiting for
693 * checkpointing. [j_list_lock]
695 transaction_t *j_checkpoint_transactions;
698 * Wait queue for waiting for a locked transaction to start committing,
699 * or for a barrier lock to be released
701 wait_queue_head_t j_wait_transaction_locked;
703 /* Wait queue for waiting for checkpointing to complete */
704 wait_queue_head_t j_wait_logspace;
706 /* Wait queue for waiting for commit to complete */
707 wait_queue_head_t j_wait_done_commit;
709 /* Wait queue to trigger checkpointing */
710 wait_queue_head_t j_wait_checkpoint;
712 /* Wait queue to trigger commit */
713 wait_queue_head_t j_wait_commit;
715 /* Wait queue to wait for updates to complete */
716 wait_queue_head_t j_wait_updates;
718 /* Semaphore for locking against concurrent checkpoints */
719 struct mutex j_checkpoint_mutex;
722 * Journal head: identifies the first unused block in the journal.
725 unsigned long j_head;
728 * Journal tail: identifies the oldest still-used block in the journal.
731 unsigned long j_tail;
734 * Journal free: how many free blocks are there in the journal?
737 unsigned long j_free;
740 * Journal start and end: the block numbers of the first usable block
741 * and one beyond the last usable block in the journal. [j_state_lock]
743 unsigned long j_first;
744 unsigned long j_last;
747 * Device, blocksize and starting block offset for the location where we
750 struct block_device *j_dev;
752 unsigned long long j_blk_offset;
755 * Device which holds the client fs. For internal journal this will be
758 struct block_device *j_fs_dev;
760 /* Total maximum capacity of the journal region on disk. */
761 unsigned int j_maxlen;
764 * Protects the buffer lists and internal buffer state.
766 spinlock_t j_list_lock;
768 /* Optional inode where we store the journal. If present, all */
769 /* journal block numbers are mapped into this inode via */
771 struct inode *j_inode;
774 * Sequence number of the oldest transaction in the log [j_state_lock]
776 tid_t j_tail_sequence;
779 * Sequence number of the next transaction to grant [j_state_lock]
781 tid_t j_transaction_sequence;
784 * Sequence number of the most recently committed transaction
787 tid_t j_commit_sequence;
790 * Sequence number of the most recent transaction wanting commit
793 tid_t j_commit_request;
796 * Journal uuid: identifies the object (filesystem, LVM volume etc)
797 * backed by this journal. This will eventually be replaced by an array
798 * of uuids, allowing us to index multiple devices within a single
799 * journal and to perform atomic updates across them.
803 /* Pointer to the current commit thread for this journal */
804 struct task_struct *j_task;
807 * Maximum number of metadata buffers to allow in a single compound
810 int j_max_transaction_buffers;
813 * What is the maximum transaction lifetime before we begin a commit?
815 unsigned long j_commit_interval;
817 /* The timer used to wakeup the commit thread: */
818 struct timer_list j_commit_timer;
821 * The revoke table: maintains the list of revoked blocks in the
822 * current transaction. [j_revoke_lock]
824 spinlock_t j_revoke_lock;
825 struct jbd2_revoke_table_s *j_revoke;
826 struct jbd2_revoke_table_s *j_revoke_table[2];
829 * array of bhs for jbd2_journal_commit_transaction
831 struct buffer_head **j_wbuf;
834 pid_t j_last_sync_writer;
837 * An opaque pointer to fs-private information. ext3 puts its
838 * superblock pointer here
844 * Journal flag definitions
846 #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */
847 #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */
848 #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */
849 #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */
850 #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */
851 #define JBD2_BARRIER 0x020 /* Use IDE barriers */
854 * Function declarations for the journaling transaction and buffer
859 extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *);
860 extern void __jbd2_journal_unfile_buffer(struct journal_head *);
861 extern void __jbd2_journal_refile_buffer(struct journal_head *);
862 extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *);
863 extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
864 extern void __journal_free_buffer(struct journal_head *bh);
865 extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
866 extern void __journal_clean_data_list(transaction_t *transaction);
868 /* Log buffer allocation */
869 extern struct journal_head * jbd2_journal_get_descriptor_buffer(journal_t *);
870 int jbd2_journal_next_log_block(journal_t *, unsigned long long *);
872 /* Commit management */
873 extern void jbd2_journal_commit_transaction(journal_t *);
875 /* Checkpoint list management */
876 int __jbd2_journal_clean_checkpoint_list(journal_t *journal);
877 int __jbd2_journal_remove_checkpoint(struct journal_head *);
878 void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *);
882 jbd2_journal_write_metadata_buffer(transaction_t *transaction,
883 struct journal_head *jh_in,
884 struct journal_head **jh_out,
885 unsigned long long blocknr);
887 /* Transaction locking */
888 extern void __wait_on_journal (journal_t *);
893 * We need to lock the journal during transaction state changes so that nobody
894 * ever tries to take a handle on the running transaction while we are in the
895 * middle of moving it to the commit phase. j_state_lock does this.
897 * Note that the locking is completely interrupt unsafe. We never touch
898 * journal structures from interrupts.
901 static inline handle_t *journal_current_handle(void)
903 return current->journal_info;
906 /* The journaling code user interface:
908 * Create and destroy handles
909 * Register buffer modifications against the current transaction.
912 extern handle_t *jbd2_journal_start(journal_t *, int nblocks);
913 extern int jbd2_journal_restart (handle_t *, int nblocks);
914 extern int jbd2_journal_extend (handle_t *, int nblocks);
915 extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *);
916 extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *);
917 extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *);
918 extern int jbd2_journal_dirty_data (handle_t *, struct buffer_head *);
919 extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *);
920 extern void jbd2_journal_release_buffer (handle_t *, struct buffer_head *);
921 extern int jbd2_journal_forget (handle_t *, struct buffer_head *);
922 extern void journal_sync_buffer (struct buffer_head *);
923 extern void jbd2_journal_invalidatepage(journal_t *,
924 struct page *, unsigned long);
925 extern int jbd2_journal_try_to_free_buffers(journal_t *, struct page *, gfp_t);
926 extern int jbd2_journal_stop(handle_t *);
927 extern int jbd2_journal_flush (journal_t *);
928 extern void jbd2_journal_lock_updates (journal_t *);
929 extern void jbd2_journal_unlock_updates (journal_t *);
931 extern journal_t * jbd2_journal_init_dev(struct block_device *bdev,
932 struct block_device *fs_dev,
933 unsigned long long start, int len, int bsize);
934 extern journal_t * jbd2_journal_init_inode (struct inode *);
935 extern int jbd2_journal_update_format (journal_t *);
936 extern int jbd2_journal_check_used_features
937 (journal_t *, unsigned long, unsigned long, unsigned long);
938 extern int jbd2_journal_check_available_features
939 (journal_t *, unsigned long, unsigned long, unsigned long);
940 extern int jbd2_journal_set_features
941 (journal_t *, unsigned long, unsigned long, unsigned long);
942 extern int jbd2_journal_create (journal_t *);
943 extern int jbd2_journal_load (journal_t *journal);
944 extern void jbd2_journal_destroy (journal_t *);
945 extern int jbd2_journal_recover (journal_t *journal);
946 extern int jbd2_journal_wipe (journal_t *, int);
947 extern int jbd2_journal_skip_recovery (journal_t *);
948 extern void jbd2_journal_update_superblock (journal_t *, int);
949 extern void __jbd2_journal_abort_hard (journal_t *);
950 extern void jbd2_journal_abort (journal_t *, int);
951 extern int jbd2_journal_errno (journal_t *);
952 extern void jbd2_journal_ack_err (journal_t *);
953 extern int jbd2_journal_clear_err (journal_t *);
954 extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *);
955 extern int jbd2_journal_force_commit(journal_t *);
958 * journal_head management
960 struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh);
961 struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh);
962 void jbd2_journal_remove_journal_head(struct buffer_head *bh);
963 void jbd2_journal_put_journal_head(struct journal_head *jh);
968 extern struct kmem_cache *jbd2_handle_cache;
970 static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags)
972 return kmem_cache_alloc(jbd2_handle_cache, gfp_flags);
975 static inline void jbd2_free_handle(handle_t *handle)
977 kmem_cache_free(jbd2_handle_cache, handle);
980 /* Primary revoke support */
981 #define JOURNAL_REVOKE_DEFAULT_HASH 256
982 extern int jbd2_journal_init_revoke(journal_t *, int);
983 extern void jbd2_journal_destroy_revoke_caches(void);
984 extern int jbd2_journal_init_revoke_caches(void);
986 extern void jbd2_journal_destroy_revoke(journal_t *);
987 extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *);
988 extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *);
989 extern void jbd2_journal_write_revoke_records(journal_t *, transaction_t *);
991 /* Recovery revoke support */
992 extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t);
993 extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t);
994 extern void jbd2_journal_clear_revoke(journal_t *);
995 extern void jbd2_journal_switch_revoke_table(journal_t *journal);
998 * The log thread user interface:
1000 * Request space in the current transaction, and force transaction commit
1001 * transitions on demand.
1004 int __jbd2_log_space_left(journal_t *); /* Called with journal locked */
1005 int jbd2_log_start_commit(journal_t *journal, tid_t tid);
1006 int __jbd2_log_start_commit(journal_t *journal, tid_t tid);
1007 int jbd2_journal_start_commit(journal_t *journal, tid_t *tid);
1008 int jbd2_journal_force_commit_nested(journal_t *journal);
1009 int jbd2_log_wait_commit(journal_t *journal, tid_t tid);
1010 int jbd2_log_do_checkpoint(journal_t *journal);
1012 void __jbd2_log_wait_for_space(journal_t *journal);
1013 extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *);
1014 extern int jbd2_cleanup_journal_tail(journal_t *);
1016 /* Debugging code only: */
1018 #define jbd_ENOSYS() \
1020 printk (KERN_ERR "JBD unimplemented function %s\n", __FUNCTION__); \
1021 current->state = TASK_UNINTERRUPTIBLE; \
1028 * Simple test wrapper function to test the JBD2_ABORT state flag. This
1029 * bit, when set, indicates that we have had a fatal error somewhere,
1030 * either inside the journaling layer or indicated to us by the client
1031 * (eg. ext3), and that we and should not commit any further
1035 static inline int is_journal_aborted(journal_t *journal)
1037 return journal->j_flags & JBD2_ABORT;
1040 static inline int is_handle_aborted(handle_t *handle)
1042 if (handle->h_aborted)
1044 return is_journal_aborted(handle->h_transaction->t_journal);
1047 static inline void jbd2_journal_abort_handle(handle_t *handle)
1049 handle->h_aborted = 1;
1052 #endif /* __KERNEL__ */
1054 /* Comparison functions for transaction IDs: perform comparisons using
1055 * modulo arithmetic so that they work over sequence number wraps. */
1057 static inline int tid_gt(tid_t x, tid_t y)
1059 int difference = (x - y);
1060 return (difference > 0);
1063 static inline int tid_geq(tid_t x, tid_t y)
1065 int difference = (x - y);
1066 return (difference >= 0);
1069 extern int jbd2_journal_blocks_per_page(struct inode *inode);
1070 extern size_t journal_tag_bytes(journal_t *journal);
1073 * Return the minimum number of blocks which must be free in the journal
1074 * before a new transaction may be started. Must be called under j_state_lock.
1076 static inline int jbd_space_needed(journal_t *journal)
1078 int nblocks = journal->j_max_transaction_buffers;
1079 if (journal->j_committing_transaction)
1080 nblocks += journal->j_committing_transaction->
1081 t_outstanding_credits;
1086 * Definitions which augment the buffer_head layer
1089 /* journaling buffer types */
1090 #define BJ_None 0 /* Not journaled */
1091 #define BJ_SyncData 1 /* Normal data: flush before commit */
1092 #define BJ_Metadata 2 /* Normal journaled metadata */
1093 #define BJ_Forget 3 /* Buffer superseded by this transaction */
1094 #define BJ_IO 4 /* Buffer is for temporary IO use */
1095 #define BJ_Shadow 5 /* Buffer contents being shadowed to the log */
1096 #define BJ_LogCtl 6 /* Buffer contains log descriptors */
1097 #define BJ_Reserved 7 /* Buffer is reserved for access by journal */
1098 #define BJ_Locked 8 /* Locked for I/O during commit */
1101 extern int jbd_blocks_per_page(struct inode *inode);
1105 #define buffer_trace_init(bh) do {} while (0)
1106 #define print_buffer_fields(bh) do {} while (0)
1107 #define print_buffer_trace(bh) do {} while (0)
1108 #define BUFFER_TRACE(bh, info) do {} while (0)
1109 #define BUFFER_TRACE2(bh, bh2, info) do {} while (0)
1110 #define JBUFFER_TRACE(jh, info) do {} while (0)
1112 #endif /* __KERNEL__ */
1114 #endif /* _LINUX_JBD_H */