Add an option to suppress the creation of the .snap directory in

the new filesystem.  This is intended for memory and vnode filesystems
that will never be fsck'ed or dumped.

Obtained from:	St. Bernard Software RAPID
MFC after:	2 weeks

4 files changed, 60 insertions, 32 deletions

diff --git a/sbin/newfs/mkfs.c b/sbin/newfs/mkfs.c
index 66074c7..b796aef 100644
--- a/sbin/newfs/mkfs.c
+++ b/sbin/newfs/mkfs.c
@@ -738,10 +738,12 @@ fsinit(time_t utime)
 {
 	union dinode node;
 	struct group *grp;
+	int entries;
 
 	memset(&node, 0, sizeof node);
 	if ((grp = getgrnam("operator")) == NULL)
 		errx(35, "Cannot retrieve operator gid");
+	entries = (nflag) ? ROOTLINKCNT - 1: ROOTLINKCNT;
 	if (sblock.fs_magic == FS_UFS1_MAGIC) {
 		/*
 		 * initialize the node
@@ -753,27 +755,30 @@ fsinit(time_t utime)
 		 * create the root directory
 		 */
 		node.dp1.di_mode = IFDIR | UMASK;
-		node.dp1.di_nlink = ROOTLINKCNT;
-		node.dp1.di_size = makedir(root_dir, ROOTLINKCNT);
+		node.dp1.di_nlink = entries;
+		node.dp1.di_size = makedir(root_dir, entries);
 		node.dp1.di_db[0] = alloc(sblock.fs_fsize, node.dp1.di_mode);
 		node.dp1.di_blocks =
 		    btodb(fragroundup(&sblock, node.dp1.di_size));
 		wtfs(fsbtodb(&sblock, node.dp1.di_db[0]), sblock.fs_fsize,
 		    iobuf);
 		iput(&node, ROOTINO);
-		/*
-		 * create the .snap directory
-		 */
-		node.dp1.di_mode |= 020;
-		node.dp1.di_gid = grp->gr_gid;
-		node.dp1.di_nlink = SNAPLINKCNT;
-		node.dp1.di_size = makedir(snap_dir, SNAPLINKCNT);
-		node.dp1.di_db[0] = alloc(sblock.fs_fsize, node.dp1.di_mode);
-		node.dp1.di_blocks =
-		    btodb(fragroundup(&sblock, node.dp1.di_size));
-		wtfs(fsbtodb(&sblock, node.dp1.di_db[0]), sblock.fs_fsize,
-		    iobuf);
-		iput(&node, ROOTINO + 1);
+		if (!nflag) {
+			/*
+			 * create the .snap directory
+			 */
+			node.dp1.di_mode |= 020;
+			node.dp1.di_gid = grp->gr_gid;
+			node.dp1.di_nlink = SNAPLINKCNT;
+			node.dp1.di_size = makedir(snap_dir, SNAPLINKCNT);
+				node.dp1.di_db[0] =
+				    alloc(sblock.fs_fsize, node.dp1.di_mode);
+			node.dp1.di_blocks =
+			    btodb(fragroundup(&sblock, node.dp1.di_size));
+				wtfs(fsbtodb(&sblock, node.dp1.di_db[0]),
+				    sblock.fs_fsize, iobuf);
+			iput(&node, ROOTINO + 1);
+		}
 	} else {
 		/*
 		 * initialize the node
@@ -786,27 +791,30 @@ fsinit(time_t utime)
 		 * create the root directory
 		 */
 		node.dp2.di_mode = IFDIR | UMASK;
-		node.dp2.di_nlink = ROOTLINKCNT;
-		node.dp2.di_size = makedir(root_dir, ROOTLINKCNT);
+		node.dp2.di_nlink = entries;
+		node.dp2.di_size = makedir(root_dir, entries);
 		node.dp2.di_db[0] = alloc(sblock.fs_fsize, node.dp2.di_mode);
 		node.dp2.di_blocks =
 		    btodb(fragroundup(&sblock, node.dp2.di_size));
 		wtfs(fsbtodb(&sblock, node.dp2.di_db[0]), sblock.fs_fsize,
 		    iobuf);
 		iput(&node, ROOTINO);
-		/*
-		 * create the .snap directory
-		 */
-		node.dp2.di_mode |= 020;
-		node.dp2.di_gid = grp->gr_gid;
-		node.dp2.di_nlink = SNAPLINKCNT;
-		node.dp2.di_size = makedir(snap_dir, SNAPLINKCNT);
-		node.dp2.di_db[0] = alloc(sblock.fs_fsize, node.dp2.di_mode);
-		node.dp2.di_blocks =
-		    btodb(fragroundup(&sblock, node.dp2.di_size));
-		wtfs(fsbtodb(&sblock, node.dp2.di_db[0]), sblock.fs_fsize,
-		    iobuf);
-		iput(&node, ROOTINO + 1);
+		if (!nflag) {
+			/*
+			 * create the .snap directory
+			 */
+			node.dp2.di_mode |= 020;
+			node.dp2.di_gid = grp->gr_gid;
+			node.dp2.di_nlink = SNAPLINKCNT;
+			node.dp2.di_size = makedir(snap_dir, SNAPLINKCNT);
+				node.dp2.di_db[0] =
+				    alloc(sblock.fs_fsize, node.dp2.di_mode);
+			node.dp2.di_blocks =
+			    btodb(fragroundup(&sblock, node.dp2.di_size));
+				wtfs(fsbtodb(&sblock, node.dp2.di_db[0]), 
+				    sblock.fs_fsize, iobuf);
+			iput(&node, ROOTINO + 1);
+		}
 	}
 }
 
diff --git a/sbin/newfs/newfs.8 b/sbin/newfs/newfs.8
index 8cba772..48393e3 100644
--- a/sbin/newfs/newfs.8
+++ b/sbin/newfs/newfs.8
@@ -36,7 +36,7 @@
 .Nd construct a new UFS1/UFS2 file system
 .Sh SYNOPSIS
 .Nm
-.Op Fl NUl
+.Op Fl NUln
 .Op Fl L Ar volname
 .Op Fl O Ar filesystem-type
 .Op Fl S Ar sector-size
@@ -159,6 +159,20 @@ currently 8%.
 See
 .Xr tunefs 8
 for more details on how to set this option.
+.It Fl n
+Do not create a .snap directory on the new filesystem.
+The resulting filesystem will not support snapshot generation, so
+.Xr dump 8
+in live mode and background
+.Xr fsck 8
+will not function properly.
+The traditional
+.Xr fsck 8
+and offline
+.Xr dump 8
+will work on the filesystem.
+This option is intended primarily for memory or vnode filesystems that
+do not require dump or fsck support.
 .It Fl o Ar optimization
 .Cm ( space
 or
@@ -219,6 +233,7 @@ on file systems that contain many small files.
 .Xr fs 5 ,
 .Xr bsdlabel 8 ,
 .Xr camcontrol 8 ,
+.Xr dump 8 ,
 .Xr dumpfs 8 ,
 .Xr fsck 8 ,
 .Xr mount 8 ,
diff --git a/sbin/newfs/newfs.c b/sbin/newfs/newfs.c
index f5a0154..24cd094 100644
--- a/sbin/newfs/newfs.c
+++ b/sbin/newfs/newfs.c
@@ -118,6 +118,7 @@ int	Rflag;			/* regression test */
 int	Uflag;			/* enable soft updates for file system */
 int	Eflag = 0;		/* exit in middle of newfs for testing */
 int	lflag;			/* enable multilabel for file system */
+int	nflag;			/* do not create .snap directory */
 quad_t	fssize;			/* file system size */
 int	sectorsize;		/* bytes/sector */
 int	realsectorsize;		/* bytes/sector in hardware */
@@ -155,7 +156,7 @@ main(int argc, char *argv[])
 	off_t mediasize;
 
 	while ((ch = getopt(argc, argv,
-	    "EL:NO:RS:T:Ua:b:c:d:e:f:g:h:i:lm:o:s:")) != -1)
+	    "EL:NO:RS:T:Ua:b:c:d:e:f:g:h:i:lm:no:s:")) != -1)
 		switch (ch) {
 		case 'E':
 			Eflag++;
@@ -244,6 +245,9 @@ main(int argc, char *argv[])
 			if ((minfree = atoi(optarg)) < 0 || minfree > 99)
 				errx(1, "%s: bad free space %%", optarg);
 			break;
+		case 'n':
+			nflag = 1;
+			break;
 		case 'o':
 			if (strcmp(optarg, "space") == 0)
 				opt = FS_OPTSPACE;
diff --git a/sbin/newfs/newfs.h b/sbin/newfs/newfs.h
index feb9bcd..dae9fd8 100644
--- a/sbin/newfs/newfs.h
+++ b/sbin/newfs/newfs.h
@@ -50,6 +50,7 @@ extern int	Rflag;		/* regression test */
 extern int	Uflag;		/* enable soft updates for file system */
 extern int	Eflag;		/* exit as if error, for testing */
 extern int	lflag;		/* enable multilabel MAC for file system */
+extern int	nflag;		/* do not create .snap directory */
 extern quad_t	fssize;		/* file system size */
 extern int	sectorsize;	/* bytes/sector */
 extern int	realsectorsize;	/* bytes/sector in hardware*/