ChangeLog, jfs_user.h, mkjournal.c:

  mkjournal.c (init_journal_superblock): Sync Stephen's changes which
  	creates a V2 superblock instead of a V1 superblock.
ChangeLog, jfs.h, jfs_compat.h, list.h:
  jfs.h, jfs_compat.h, list.h: New files added to support ext3.

7 files changed, 836 insertions, 4 deletions

diff --git a/include/linux/ChangeLog b/include/linux/ChangeLog
index 0067f461..d9c81a1f 100644
--- a/include/linux/ChangeLog
+++ b/include/linux/ChangeLog
@@ -1,3 +1,7 @@
+2000-12-09    <tytso@snap.thunk.org>
+
+	* jfs.h, jfs_compat.h, list.h: New files added to support ext3.
+
 2000-10-24    <tytso@valinux.com>
 
 	* ext2_fs.h (EXT2_JOURNAL_INO): Add definition for
diff --git a/include/linux/jfs.h b/include/linux/jfs.h
new file mode 100644
index 00000000..fffd8df0
--- /dev/null
+++ b/include/linux/jfs.h
@@ -0,0 +1,650 @@
+/*
+ * linux/include/linux/jfs.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_JFS_H
+#define _LINUX_JFS_H
+
+/* Allow this file to be included directly into e2fsprogs */
+#ifndef __KERNEL__
+#include "jfs_compat.h"
+#endif
+
+/*
+ * Debug code enabled by default for kernel builds
+ */
+#ifdef __KERNEL__
+#define JFS_DEBUG
+#else
+#define JFS_DEBUG
+#endif
+
+extern int journal_enable_debug;
+
+#ifdef JFS_DEBUG
+#define jfs_debug(n, f, a...)						\
+	do {								\
+		if ((n) <= journal_enable_debug) {			\
+			printk (KERN_DEBUG "JFS DEBUG: (%s, %d): %s: ",	\
+				__FILE__, __LINE__, __FUNCTION__);	\
+		  	printk (f, a);					\
+		}							\
+	} while (0)
+#else
+#define jfs_debug(f, a...)	/**/
+#endif
+
+#define JFS_MIN_JOURNAL_BLOCKS 1024
+
+/*
+ * 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
+{
+	__u32		h_magic;
+	__u32		h_blocktype;
+	__u32		h_sequence;
+} journal_header_t;
+
+
+/* 
+ * The block tag: used to describe a single buffer in the journal 
+ */
+typedef struct journal_block_tag_s
+{
+	__u32		t_blocknr;	/* The on-disk block number */
+	__u32		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;
+	int		 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 */
+	__u32	s_blocksize;		/* journal device blocksize */
+	__u32	s_maxlen;		/* total blocks in journal file */
+	__u32	s_first;		/* first block of log information */
+	
+/* 0x0018 */
+	/* Dynamic information describing the current state of the log */
+	__u32	s_sequence;		/* first commit ID expected in log */
+	__u32	s_start;		/* blocknr of start of log */
+
+/* 0x0020 */
+	/* Error value, as set by journal_abort(). */
+	__s32	s_errno;
+
+/* 0x0024 */
+	/* Remaining fields are only valid in a version-2 superblock */
+	__u32	s_feature_compat; 	/* compatible feature set */
+	__u32	s_feature_incompat; 	/* incompatible feature set */
+	__u32	s_feature_ro_compat; 	/* readonly-compatible feature set */
+/* 0x0030 */
+	__u8	s_uuid[16];		/* 128-bit uuid for journal */
+
+/* 0x0040 */
+	__u32	s_nr_users;		/* Nr of filesystems sharing log */
+	
+	__u32	s_dynsuper;		/* Blocknr of dynamic superblock copy*/
+	
+/* 0x0048 */
+	__u32	s_max_transaction;	/* Limit of journal blocks per trans.*/
+	__u32	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>
+
+
+#define J_ASSERT(assert)						\
+	do { if (!(assert)) {						\
+		printk (KERN_EMERG					\
+			"Assertion failure in %s() at %s line %d: "	\
+			"\"%s\"\n",					\
+			__FUNCTION__, __FILE__, __LINE__, # assert);	\
+		* ((char *) 0) = 0;					\
+	} } while (0)
+
+
+struct jfs_revoke_table_s;
+
+/* 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. */
+
+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;
+
+	/* Flags */
+	unsigned int		h_sync	: 1;	/* sync-on-close */
+	unsigned int		h_jdata	: 1;	/* force data journaling */
+};
+
+
+/* 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.
+ */
+
+struct transaction_s 
+{
+	/* Pointer to the journal for this transaction. */
+	journal_t *		t_journal;
+	
+	/* Sequence number for this transaction */
+	tid_t			t_tid;
+	
+	/* Transaction's current state */
+	enum {
+		T_RUNNING,
+		T_LOCKED,
+		T_RUNDOWN,
+		T_FLUSH,
+		T_COMMIT,
+		T_FINISHED 
+	}			t_state;
+
+	/* Where in the log does this transaction's commit start? */
+	unsigned long		t_log_start;
+	
+	/* Doubly-linked circular list of all inodes owned by this
+           transaction */
+	struct inode *		t_ilist;
+	
+	/* Number of buffers on the t_buffers list */
+	int			t_nr_buffers;
+	
+	/* Doubly-linked circular list of all buffers reserved but not
+           yet modified by this transaction */
+	struct buffer_head *	t_reserved_list;
+	
+	/* Doubly-linked circular list of all metadata buffers owned by this
+           transaction */
+	struct buffer_head *	t_buffers;
+	
+	/* Doubly-linked circular list of all data buffers still to be
+           flushed before this transaction can be committed */
+	struct buffer_head *	t_datalist;
+	
+	/* Doubly-linked circular list of all forget buffers (superceded
+           buffers which we can un-checkpoint once this transaction
+           commits) */
+	struct buffer_head *	t_forget;
+	
+	/* Doubly-linked circular list of all buffers still to be
+           flushed before this transaction can be checkpointed */
+	struct buffer_head *	t_checkpoint_list;
+	
+	/* Doubly-linked circular list of temporary buffers currently
+           undergoing IO in the log */
+	struct buffer_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. */
+	struct buffer_head *	t_shadow_list;
+	
+	/* Doubly-linked circular list of control buffers being written
+           to the log. */
+	struct buffer_head *	t_log_list;
+	
+	/* Number of outstanding updates running on this transaction */
+	int			t_updates;
+
+	/* Number of buffers reserved for use by all handles in this
+	 * transaction handle but not yet modified. */
+	int			t_outstanding_credits;
+	
+	/* Wait queue to wait for updates to complete */
+	struct wait_queue *	t_wait;
+
+	/* Forward and backward links for the circular list of all
+	 * transactions awaiting checkpoint */
+	transaction_t		*t_cpnext, *t_cpprev;
+
+	/* When will the transaction expire (become due for commit), in
+	 * jiffies ? */
+	unsigned long		t_expires;
+};
+
+
+/* The journal_t maintains all of the journaling state information for a
+ * single filesystem.  It 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. */
+
+struct journal_s
+{
+	/* General journaling state flags */
+	unsigned long		j_flags;
+
+	/* Is there an outstanding uncleared error on the journal (from
+	 * a prior abort)? */
+	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;
+	
+	/* Transactions: The current running transaction... */
+	transaction_t *		j_running_transaction;
+	
+	/* ... the transaction we are pushing to disk ... */
+	transaction_t *		j_committing_transaction;
+	
+	/* ... and a linked circular list of all transactions waiting
+	 * for checkpointing. */
+	transaction_t *		j_checkpoint_transactions;
+
+	/* Wait queue for locking of the journal structure.  */
+	struct wait_queue *	j_wait_lock;
+
+	/* Wait queue for waiting for a locked transaction to start
+           committing */
+	struct wait_queue *	j_wait_transaction_locked;
+	
+	/* Wait queue for waiting for checkpointing to complete */
+	struct wait_queue *	j_wait_logspace;
+	
+	/* Wait queue for waiting for commit to complete */
+	struct wait_queue *	j_wait_done_commit;
+	
+	/* Wait queue to trigger checkpointing */
+	struct wait_queue *	j_wait_checkpoint;
+	
+	/* Wait queue to trigger commit */
+	struct wait_queue *	j_wait_commit;
+	
+	/* Semaphore for locking against concurrent checkpoints */
+	struct semaphore 	j_checkpoint_sem;
+		
+	/* Journal running state: */
+	/* The lock flag is *NEVER* touched from interrupts. */
+	unsigned int		j_locked : 1;
+
+	/* Journal head: identifies the first unused block in the journal. */
+	unsigned long		j_head;
+	
+	/* Journal tail: identifies the oldest still-used block in the
+	 * journal. */
+	unsigned long		j_tail;
+
+	/* Journal free: how many free blocks are there in the journal? */
+	unsigned long		j_free;
+
+	/* Journal start and end: the block numbers of the first usable
+	 * block and one beyond the last usable block in the journal. */
+	unsigned long		j_first, j_last;
+
+	/* Device, blocksize and starting block offset for the location
+	 * where we store the journal. */
+	kdev_t			j_dev;
+	int			j_blocksize;
+	unsigned int		j_blk_offset;
+
+	/* Total maximum capacity of the journal region on disk. */
+	unsigned int		j_maxlen;
+
+	/* 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 */
+	tid_t			j_tail_sequence;
+	/* Sequence number of the next transaction to grant */
+	tid_t			j_transaction_sequence;
+	/* Sequence number of the most recently committed transaction */
+	tid_t			j_commit_sequence;
+	/* Sequence number of the most recent transaction wanting commit */
+	tid_t			j_commit_request;
+
+	/* 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;
+	int			j_commit_timer_active;
+
+	/* The revoke table: maintains the list of revoked blocks in the
+           current transaction. */
+	struct jfs_revoke_table_s *j_revoke;
+};
+
+/* 
+ * Journal flag definitions 
+ */
+#define JFS_UNMOUNT	1	/* Journal thread is being destroyed */
+#define JFS_SYNC	2	/* Perform synchronous transaction commits */
+#define JFS_ABORT	4	/* Journaling has been aborted for errors. */
+#define JFS_ACK_ERR	8	/* The errno in the sb has been acked */
+
+/* 
+ * Journaling internal variables/parameters 
+ */
+
+extern int journal_flush_nr_buffers;
+
+
+/* 
+ * Function declarations for the journaling transaction and buffer
+ * management
+ */
+
+/* Filing buffers */
+extern void journal_unfile_buffer(struct buffer_head *);
+extern void journal_refile_buffer(struct buffer_head *);
+extern void journal_file_buffer(struct buffer_head *, transaction_t *, int);
+extern void journal_clean_data_list(transaction_t *transaction);
+
+/* Log buffer allocation */
+extern struct buffer_head * journal_get_descriptor_buffer(journal_t *);
+extern unsigned long journal_next_log_block(journal_t *);
+
+/* Commit management */
+extern void journal_commit_transaction(journal_t *);
+
+/* Checkpoint list management */
+extern void journal_remove_checkpoint(struct buffer_head *);
+extern void journal_insert_checkpoint(struct buffer_head *, transaction_t *);
+
+/* Buffer IO */
+extern int 
+journal_write_metadata_buffer(transaction_t	  *transaction,
+			      struct buffer_head  *bh_in,
+			      struct buffer_head **bh_out,
+			      int		   blocknr);
+
+/* Create and destroy transactions */
+extern transaction_t *	get_transaction (journal_t *);
+extern void		put_transaction (transaction_t *);
+
+/* Notify state transitions (called by the log writer thread): */
+extern int		set_transaction_state (transaction_t *, int);
+
+
+/* Transaction locking */
+extern void		__wait_on_journal (journal_t *);
+
+/* Journal locking.  In 2.2, we assume that the kernel lock is already
+ * held. */
+static inline void lock_journal (journal_t * journal)
+{
+#ifdef __SMP__
+	J_ASSERT(current->lock_depth >= 0);
+#endif
+	if (journal->j_locked)
+		__wait_on_journal(journal);
+	journal->j_locked = 1;
+}
+
+static inline int try_lock_journal (journal_t * journal)
+{
+	if (journal->j_locked)
+		return 1;
+	journal->j_locked = 1;
+	return 0;
+}
+
+static inline void unlock_journal (journal_t * journal)
+{
+	J_ASSERT (journal->j_locked);
+	journal->j_locked = 0;
+	wake_up(&journal->j_wait_lock);
+}
+
+/* This function is gross, but unfortunately we need it as long as
+ * existing filesystems want to guard against races by testing
+ * bh->b_count.  @@@ Remove this?  We no longer abuse b_count so badly!
+ */
+
+static inline int journal_is_buffer_shared(struct buffer_head *bh)
+{
+	int count = bh->b_count;
+	J_ASSERT (count >= 1);
+	return (count > 1);
+}
+
+/* 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 void	 journal_forget (handle_t *, struct buffer_head *);
+extern void	 journal_sync_buffer (struct buffer_head *);
+extern int	 journal_stop (handle_t *);
+extern int	 journal_flush (journal_t *);
+
+extern journal_t * journal_init_dev   (kdev_t, 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 *);
+extern void	   journal_release    (journal_t *);
+extern int	   journal_recover    (journal_t *);
+extern void	   journal_update_superblock (journal_t *, int);
+extern void	   __journal_abort      (journal_t *);
+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 *);
+
+/* Primary revoke support */
+#define JOURNAL_REVOKE_DEFAULT_HASH 256
+extern int	   journal_init_revoke(journal_t *, int);
+extern void	   journal_destroy_revoke(journal_t *);
+extern int	   journal_revoke (handle_t *, unsigned long, struct buffer_head *);
+extern void	   journal_cancel_revoke(handle_t *, struct buffer_head *);
+extern void	   journal_write_revoke_records(journal_t *, transaction_t *);
+
+/* Recovery revoke support */
+extern int	   journal_set_revoke(journal_t *, unsigned long, tid_t);
+extern int	   journal_test_revoke(journal_t *, unsigned long, tid_t);
+extern void	   journal_clear_revoke(journal_t *);
+
+
+/* The log thread user interface:
+ *
+ * Request space in the current transaction, and force transaction commit
+ * transitions on demand.
+ */
+
+extern int	log_space_left (journal_t *); /* Called with journal locked */
+extern void	log_start_commit (journal_t *, transaction_t *);
+extern void	log_wait_commit (journal_t *, tid_t);
+extern int	log_do_checkpoint (journal_t *, int);
+
+extern void	log_wait_for_space(journal_t *, int nblocks);
+extern void	journal_drop_transaction(journal_t *, transaction_t *);
+extern int	cleanup_journal_tail(journal_t *);
+
+
+/* Debugging code only: */
+
+#define jfs_ENOSYS() \
+do {								      \
+	printk (KERN_ERR "JFS unimplemented function " __FUNCTION__); \
+	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_abort(journal_t *journal)
+{
+	return journal->j_flags & JFS_ABORT;
+}
+
+#endif /* __KERNEL__   */
+
+/* Comparison functions for transaction IDs: perform comparisons using
+ * modulo arithmetic so that they work over sequence number wraps. */
+
+static inline int tid_ge(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);
+}
+
+
+#endif /* _LINUX_JFS_H */
diff --git a/include/linux/jfs_compat.h b/include/linux/jfs_compat.h
new file mode 100644
index 00000000..8d87753b
--- /dev/null
+++ b/include/linux/jfs_compat.h
@@ -0,0 +1,56 @@
+
+#ifndef _JFS_COMPAT_H
+#define _JFS_COMPAT_H
+
+#include <linux/list.h>
+#include <errno.h>
+
+#define printk printf
+#define KERN_ERR ""
+#define KERN_DEBUG ""
+
+#define READ 0
+#define WRITE 1
+
+#define cpu_to_be32(n) htonl(n)
+#define be32_to_cpu(n) ntohl(n)
+
+typedef int tid_t;
+typedef struct journal_s journal_t;
+
+struct buffer_head;
+struct inode;
+
+struct journal_s
+{
+	unsigned long		j_flags;
+	int			j_errno;
+	struct buffer_head *	j_sb_buffer;
+	struct journal_superblock_s *j_superblock;
+	int			j_format_version;
+	unsigned long		j_head;
+	unsigned long		j_tail;
+	unsigned long		j_free;
+	unsigned long		j_first, j_last;
+	kdev_t			j_dev;
+	int			j_blocksize;
+	unsigned int		j_blk_offset;
+	unsigned int		j_maxlen;
+	struct inode *		j_inode;
+	tid_t			j_tail_sequence;
+	tid_t			j_transaction_sequence;
+	__u8			j_uuid[16];
+	struct jfs_revoke_table_s *j_revoke;
+};
+
+#define J_ASSERT(assert)						\
+	do { if (!(assert)) {						\
+		printf ("Assertion failure in %s() at %s line %d: "	\
+			"\"%s\"\n",					\
+			__FUNCTION__, __FILE__, __LINE__, # assert);	\
+		fatal_error(e2fsck_global_ctx, 0);			\
+	} } while (0)
+
+#define is_journal_abort(x) 0
+
+#endif /* _JFS_COMPAT_H */
diff --git a/include/linux/list.h b/include/linux/list.h
new file mode 100644
index 00000000..0e26f1fb
--- /dev/null
+++ b/include/linux/list.h
@@ -0,0 +1,108 @@
+#ifndef _LINUX_LIST_H
+#define _LINUX_LIST_H
+
+/*
+ * Simple doubly linked list implementation.
+ *
+ * Some of the internal functions ("__xxx") are useful when
+ * manipulating whole lists rather than single entries, as
+ * sometimes we already know the next/prev entries and we can
+ * generate better code by using them directly rather than
+ * using the generic single-entry routines.
+ */
+
+struct list_head {
+	struct list_head *next, *prev;
+};
+
+#define LIST_HEAD_INIT(name) { &(name), &(name) }
+
+#define LIST_HEAD(name) \
+	struct list_head name = { &name, &name }
+
+#define INIT_LIST_HEAD(ptr) do { \
+	(ptr)->next = (ptr); (ptr)->prev = (ptr); \
+} while (0)
+
+/*
+ * Insert a new entry between two known consecutive entries. 
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static __inline__ void __list_add(struct list_head * new,
+	struct list_head * prev,
+	struct list_head * next)
+{
+	next->prev = new;
+	new->next = next;
+	new->prev = prev;
+	prev->next = new;
+}
+
+/*
+ * Insert a new entry after the specified head..
+ */
+static __inline__ void list_add(struct list_head *new, struct list_head *head)
+{
+	__list_add(new, head, head->next);
+}
+
+/*
+ * Insert a new entry at the tail
+ */
+static __inline__ void list_add_tail(struct list_head *new, struct list_head *head)
+{
+	__list_add(new, head->prev, head);
+}
+
+/*
+ * Delete a list entry by making the prev/next entries
+ * point to each other.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static __inline__ void __list_del(struct list_head * prev,
+				  struct list_head * next)
+{
+	next->prev = prev;
+	prev->next = next;
+}
+
+static __inline__ void list_del(struct list_head *entry)
+{
+	__list_del(entry->prev, entry->next);
+}
+
+static __inline__ int list_empty(struct list_head *head)
+{
+	return head->next == head;
+}
+
+/*
+ * Splice in "list" into "head"
+ */
+static __inline__ void list_splice(struct list_head *list, struct list_head *head)
+{
+	struct list_head *first = list->next;
+
+	if (first != list) {
+		struct list_head *last = list->prev;
+		struct list_head *at = head->next;
+
+		first->prev = head;
+		head->next = first;
+
+		last->next = at;
+		at->prev = last;
+	}
+}
+
+#define list_entry(ptr, type, member) \
+	((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member)))
+
+#define list_for_each(pos, head) \
+        for (pos = (head)->next; pos != (head); pos = pos->next)
+
+#endif
diff --git a/lib/ext2fs/ChangeLog b/lib/ext2fs/ChangeLog
index 9f931d13..44f4fefc 100644
--- a/lib/ext2fs/ChangeLog
+++ b/lib/ext2fs/ChangeLog
@@ -1,3 +1,8 @@
+2000-12-09    <tytso@snap.thunk.org>
+
+	* mkjournal.c (init_journal_superblock): Sync Stephen's changes
+		which creates a V2 superblock instead of a V1 superblock.
+
 2000-11-21    <tytso@snap.thunk.org>
 
 	* test_io.c (test_write_blk, test_write_byte): Fix typos pointed
diff --git a/lib/ext2fs/jfs_user.h b/lib/ext2fs/jfs_user.h
new file mode 100644
index 00000000..17a82c7b
--- /dev/null
+++ b/lib/ext2fs/jfs_user.h
@@ -0,0 +1,9 @@
+#ifndef _JFS_USER_H
+#define _JFS_USER_H
+
+typedef unsigned short kdev_t;
+
+#include <linux/jfs.h>
+
+
+#endif /* _JFS_USER_H */
diff --git a/lib/ext2fs/mkjournal.c b/lib/ext2fs/mkjournal.c
index 2ef427a7..fcb01e34 100644
--- a/lib/ext2fs/mkjournal.c
+++ b/lib/ext2fs/mkjournal.c
@@ -36,19 +36,19 @@
 #endif
 
 #include "ext2fs.h"
-#include "jfs_dat.h"
+#include "jfs_user.h"
 
 static void init_journal_superblock(journal_superblock_t *jsb,
 				    __u32 blocksize, __u32 size)
 {
+	memset (jsb, 0, sizeof(*jsb));
+
 	jsb->s_header.h_magic = htonl(JFS_MAGIC_NUMBER);
-	jsb->s_header.h_blocktype = htonl(JFS_SUPERBLOCK);
-	jsb->s_header.h_sequence = 0;
+	jsb->s_header.h_blocktype = htonl(JFS_SUPERBLOCK_V2);
 	jsb->s_blocksize = htonl(blocksize);
 	jsb->s_maxlen = htonl(size);
 	jsb->s_first = htonl(1);
 	jsb->s_sequence = htonl(1);
-	jsb->s_start = 0;
 }
 	
 /*