diff -ru V7EM/h/param.h V7JEM/h/param.h
--- V7EM/h/param.h	Tue Jan 29 18:15:02 2002
+++ V7JEM/h/param.h	Sun Mar  3 01:43:53 2002
@@ -2,6 +2,8 @@
  * tunable variables
  */
 
+#define JOURNALING
+
 #define	NBUF	29		/* size of buffer cache */
 #define	NINODE	200		/* number of in core inodes */
 #define	NFILE	175		/* number of in core file structures */
diff -ru V7EM/h/systm.h V7JEM/h/systm.h
--- V7EM/h/systm.h	Mon Jan 28 06:52:32 2002
+++ V7JEM/h/systm.h	Sun Mar  3 03:01:14 2002
@@ -3,12 +3,12 @@
  * used by more than one
  * routine.
  */
-char	canonb[CANBSIZ];	/* buffer for erase and kill (#@) */
-struct inode *rootdir;		/* pointer to inode of root directory */
-struct proc *runq;		/* head of linked list of running processes */
-int	cputype;		/* type of cpu =40, 45, or 70 */
-int	lbolt;			/* time of day in 60th not in time */
-time_t	time;			/* time in sec from 1970 */
+extern char	canonb[CANBSIZ];	/* buffer for erase and kill (#@) */
+extern struct inode *rootdir;		/* pointer to inode of root directory */
+extern struct proc *runq;		/* head of linked list of running processes */
+extern int	cputype;		/* type of cpu =40, 45, or 70 */
+extern int	lbolt;			/* time of day in 60th not in time */
+extern time_t	time;			/* time in sec from 1970 */
 
 /*
  * Nblkdev is the number of entries
@@ -18,58 +18,58 @@
  * Used in bounds checking on major
  * device numbers.
  */
-int	nblkdev;
+extern int	nblkdev;
 
 /*
  * Number of character switch entries.
  * Set by cinit/tty.c
  */
-int	nchrdev;
+extern int	nchrdev;
 
-int	mpid;			/* generic for unique process id's */
-char	runin;			/* scheduling flag */
-char	runout;			/* scheduling flag */
-char	runrun;			/* scheduling flag */
-char	curpri;			/* more scheduling */
-int	maxmem;			/* actual max memory per process */
-physadr	lks;			/* pointer to clock device */
-daddr_t	swplo;			/* block number of swap space */
-int	nswap;			/* size of swap space */
-int	updlock;		/* lock for sync */
-daddr_t	rablock;		/* block to be read ahead */
+extern int	mpid;			/* generic for unique process id's */
+extern char	runin;			/* scheduling flag */
+extern char	runout;			/* scheduling flag */
+extern char	runrun;			/* scheduling flag */
+extern char	curpri;			/* more scheduling */
+extern int	maxmem;			/* actual max memory per process */
+extern physadr	lks;			/* pointer to clock device */
+extern daddr_t	swplo;			/* block number of swap space */
+extern int	nswap;			/* size of swap space */
+extern int	updlock;		/* lock for sync */
+extern daddr_t	rablock;		/* block to be read ahead */
 extern	char	regloc[];	/* locs. of saved user registers (trap.c) */
-char	msgbuf[MSGBUFS];	/* saved "printf" characters */
-dev_t	rootdev;		/* device of the root */
-dev_t	swapdev;		/* swapping device */
-dev_t	pipedev;		/* pipe device */
+extern char	msgbuf[MSGBUFS];	/* saved "printf" characters */
+extern dev_t	rootdev;		/* device of the root */
+extern dev_t	swapdev;		/* swapping device */
+extern dev_t	pipedev;		/* pipe device */
 extern	int	icode[];	/* user init code */
 extern	int	szicode;	/* its size */
 
-dev_t getmdev();
-daddr_t	bmap();
-struct inode *ialloc();
-struct inode *iget();
-struct inode *owner();
-struct inode *maknode();
-struct inode *namei();
-struct buf *alloc();
-struct buf *getblk();
-struct buf *geteblk();
-struct buf *bread();
-struct buf *breada();
-struct filsys *getfs();
-struct file *getf();
-struct file *falloc();
-int	uchar();
+extern dev_t getmdev();
+extern daddr_t	bmap();
+extern struct inode *ialloc();
+extern struct inode *iget();
+extern struct inode *owner();
+extern struct inode *maknode();
+extern struct inode *namei();
+extern struct buf *alloc();
+extern struct buf *getblk();
+extern struct buf *geteblk();
+extern struct buf *bread();
+extern struct buf *breada();
+extern struct filsys *getfs();
+extern struct file *getf();
+extern struct file *falloc();
+extern int	uchar();
 /*
  * Instrumentation
  */
-int	dk_busy;
-long	dk_time[32];
-long	dk_numb[3];
-long	dk_wds[3];
-long	tk_nin;
-long	tk_nout;
+extern int	dk_busy;
+extern long	dk_time[32];
+extern long	dk_numb[3];
+extern long	dk_wds[3];
+extern long	tk_nin;
+extern long	tk_nout;
 
 /*
  * Structure of the system-entry table
diff -ru V7EM/h/trans.h V7JEM/h/trans.h
--- V7EM/h/trans.h	Sun Mar  3 03:37:45 2002
+++ V7JEM/h/trans.h	Sun Mar  3 01:01:43 2002
@@ -0,0 +1,11 @@
+
+struct trans {
+	int t_gen;	/* generation no : for test */
+	int t_opcount;	/* op serial : for test */
+};
+
+#define TOP_USED	1
+#define TOP_SUPER	2
+#define TOP_FREE	3
+#define TOP_INODE	4
+#define TOP_ILIST	5
diff -ru V7EM/h/user.h V7JEM/h/user.h
--- V7EM/h/user.h	Mon Jan 28 07:02:49 2002
+++ V7JEM/h/user.h	Sun Mar  3 01:43:12 2002
@@ -94,6 +94,7 @@
 					 * extends from u + USIZE*64
 					 * backward not to reach here
 					 */
+	struct trans *u_tp;		/* transaction pointer */
 };
 
 #define r_val1	u_rv.ur_val1
diff -ru V7EM/sys/Makefile V7JEM/sys/Makefile
--- V7EM/sys/Makefile	Tue Jan 29 19:04:01 2002
+++ V7JEM/sys/Makefile	Sun Mar  3 01:02:35 2002
@@ -2,7 +2,8 @@
 CFLAGS=-O -g -traditional -DFSEM
 
 SRCS= alloc.c bio.c fio.c iget.c nami.c pipe.c rdwri.c \
-setup.c subr.c c.c prf.c sys2.c sys3.c sys4.c mkdir.c rmdir.c pwd.c em.c 
+setup.c subr.c c.c prf.c sys2.c sys3.c sys4.c mkdir.c rmdir.c pwd.c em.c \
+trans.c
 
 OBJS=$(SRCS:.c=.o)
 
diff -ru V7EM/sys/alloc.c V7JEM/sys/alloc.c
--- V7EM/sys/alloc.c	Tue Jan 29 18:01:20 2002
+++ V7JEM/sys/alloc.c	Sun Mar  3 03:12:11 2002
@@ -9,6 +9,7 @@
 #include "../h/ino.h"
 #include "../h/dir.h"
 #include "../h/user.h"
+#include "../h/trans.h"
 typedef	struct fblk *FBLKP;
 
 /*
@@ -114,7 +115,12 @@
 			}
 		}
 		fp->s_nfree = 0;
+#ifdef JOURNALING
+		trans_add(u.u_tp,bp,TOP_FREE,0,sizeof(fp->s_free));
+		bdwrite(bp);
+#else
 		bwrite(bp);
+#endif
 		fp->s_flock = 0;
 		wakeup((caddr_t)&fp->s_flock);
 	}
diff -ru V7EM/sys/c.c V7JEM/sys/c.c
--- V7EM/sys/c.c	Tue Jan 29 16:42:04 2002
+++ V7JEM/sys/c.c	Sun Mar  3 03:05:03 2002
@@ -11,6 +11,63 @@
 #include "../h/inode.h"
 #include "../h/acct.h"
 
+/* h/systm.h common data */
+/*
+ * Random set of variables
+ * used by more than one
+ * routine.
+ */
+char	canonb[CANBSIZ];	/* buffer for erase and kill (#@) */
+struct inode *rootdir;		/* pointer to inode of root directory */
+struct proc *runq;		/* head of linked list of running processes */
+int	cputype;		/* type of cpu =40, 45, or 70 */
+int	lbolt;			/* time of day in 60th not in time */
+time_t	time;			/* time in sec from 1970 */
+
+/*
+ * Nblkdev is the number of entries
+ * (rows) in the block switch. It is
+ * set in binit/bio.c by making
+ * a pass over the switch.
+ * Used in bounds checking on major
+ * device numbers.
+ */
+int	nblkdev;
+
+/*
+ * Number of character switch entries.
+ * Set by cinit/tty.c
+ */
+int	nchrdev;
+
+int	mpid;			/* generic for unique process id's */
+char	runin;			/* scheduling flag */
+char	runout;			/* scheduling flag */
+char	runrun;			/* scheduling flag */
+char	curpri;			/* more scheduling */
+int	maxmem;			/* actual max memory per process */
+physadr	lks;			/* pointer to clock device */
+daddr_t	swplo;			/* block number of swap space */
+int	nswap;			/* size of swap space */
+int	updlock;		/* lock for sync */
+daddr_t	rablock;		/* block to be read ahead */
+char	msgbuf[MSGBUFS];	/* saved "printf" characters */
+dev_t	rootdev;		/* device of the root */
+dev_t	swapdev;		/* swapping device */
+dev_t	pipedev;		/* pipe device */
+
+/*
+ * Instrumentation
+ */
+int	dk_busy;
+long	dk_time[32];
+long	dk_numb[3];
+long	dk_wds[3];
+long	tk_nin;
+long	tk_nout;
+ 
+/* end systm definition */
+
 int	nulldev();
 int	nodev();
 int	emstrategy();
diff -ru V7EM/sys/iget.c V7JEM/sys/iget.c
--- V7EM/sys/iget.c	Tue Jan 29 16:03:04 2002
+++ V7JEM/sys/iget.c	Sun Mar  3 02:41:48 2002
@@ -8,6 +8,7 @@
 #include "../h/filsys.h"
 #include "../h/conf.h"
 #include "../h/buf.h"
+#include "../h/trans.h"
 
 /*
  * Look up an inode by device,inumber.
@@ -217,6 +218,11 @@
 			CONV_TO_DISKORDER4(&(dp->di_ctime));
 		}
 		ip->i_flag &= ~(IUPD|IACC|ICHG);
+#ifdef JOURNALING
+		trans_add(u.u_tp, bp, TOP_INODE
+			, itoo(ip->i_number)*sizeof(struct dinode)
+			, (itoo(ip->i_number)+1)*sizeof(struct dinode));
+#endif
 		bdwrite(bp);
 	}
 }
diff -ru V7EM/sys/subr.c V7JEM/sys/subr.c
--- V7EM/sys/subr.c	Tue Jan 29 17:53:45 2002
+++ V7JEM/sys/subr.c	Sun Mar  3 03:06:50 2002
@@ -5,6 +5,7 @@
 #include "../h/dir.h"
 #include "../h/user.h"
 #include "../h/buf.h"
+#include "../h/trans.h"
 
 /*
  * Bmap defines the structure of file system storage
@@ -42,9 +43,15 @@
 			if(rwflg==B_READ || (bp = alloc(dev))==NULL)
 				return((daddr_t)-1);
 			nb = bp->b_blkno;
+#ifdef JOURNALING
+			trans_add(u.u_tp, bp, TOP_USED, 0, 0);
+#endif
 			bdwrite(bp);
 			ip->i_un.i_addr[i] = nb;
 			ip->i_flag |= IUPD|ICHG;
+#ifdef JOURNALING
+			iupdat(ip, &time, &time);
+#endif
 		}
 		if(i < NADDR-4)
 			rablock = ip->i_un.i_addr[i+1];
@@ -83,6 +90,9 @@
 		bdwrite(bp);
 		ip->i_un.i_addr[NADDR-j] = nb;
 		ip->i_flag |= IUPD|ICHG;
+#ifdef JOURNALING
+		iupdat(ip, &time, &time);
+#endif
 	}
 
 	/*
@@ -105,9 +115,15 @@
 				return((daddr_t)-1);
 			}
 			nb = nbp->b_blkno;
+#ifdef JOURNALING
+			if (j==3) trans_add(u.u_tp, nbp, TOP_USED, 0, 0);
+#endif
 			bdwrite(nbp);
 			bap[i] = nb;
 			CONV_TO_DISKORDER4(bap+i);
+#ifdef JOURNALING
+			trans_add(u.u_tp, bp, TOP_ILIST, sizeof(daddr_t)*i,sizeof(daddr_t)*(i+1));
+#endif
 			bdwrite(bp);
 		} else
 			brelse(bp);
diff -ru V7EM/sys/trans.c V7JEM/sys/trans.c
--- V7EM/sys/trans.c	Sun Mar  3 03:37:48 2002
+++ V7JEM/sys/trans.c	Sun Mar  3 01:01:58 2002
@@ -0,0 +1,65 @@
+#include "../h/param.h"
+#include "../h/systm.h"
+#include "../h/seg.h"
+#include "../h/buf.h"
+#include "../h/conf.h"
+#include "../h/trans.h"
+
+struct trans * trans_get();
+void trans_add(struct trans *tp,struct buf *bp,int op,int from,int to);
+void trans_put(struct trans *tp);
+
+static int gen=1;
+
+extern void *kmemalloc(int size);
+extern void kmemfree(void *p,int size);
+
+struct trans * trans_get() {
+	struct trans *tp;
+	tp = kmemalloc(sizeof(struct trans));
+	tp->t_gen = gen++;
+	tp->t_opcount = 0;
+	return tp;
+}
+
+void trans_put(struct trans *tp) {
+	kmemfree(tp, sizeof(struct trans));
+}
+
+void trans_add(struct trans *tp,struct buf *bp,int op,int from,int to) {
+	if (!tp) {
+printf("%s: bno = %d %d - %d\n"
+	, (op == TOP_USED)?"TOP_USED"
+	 :(op == TOP_SUPER)?"TOP_SUPER"
+	 :(op == TOP_FREE)?"TOP_FREE"
+	 :(op == TOP_INODE)?"TOP_INODE"
+	 :(op == TOP_ILIST)?"TOP_ILIST"
+	 :"TOP_ERROR"
+	,bp->b_blkno,from,to);
+	return;
+	}
+	tp->t_opcount ++;
+printf("%s: %d %d bno = %d %d - %d\n"
+	, (op == TOP_USED)?"TOP_USED"
+	 :(op == TOP_SUPER)?"TOP_SUPER"
+	 :(op == TOP_FREE)?"TOP_FREE"
+	 :(op == TOP_INODE)?"TOP_INODE"
+	 :(op == TOP_ILIST)?"TOP_ILIST"
+	 :"TOP_ERROR"
+	,tp->t_gen,tp->t_opcount,bp->b_blkno,from,to);
+}
+
+
+#undef free
+#undef malloc
+
+void *kmemalloc(int size) {
+	extern void *malloc();
+	return malloc(size);
+}
+
+void kmemfree(void *p, int size) {
+	free(p);
+}
+
+