Rename the undocumented -E option to -X.

Implement -E option which will erase the filesystem sectors before
making the new filesystem.  Reserved space in front of the superblock
(bootcode) is not erased.

NB: Erasing can take as long time as writing every sector sequentially.

This is relevant for all flash based disks which use wearlevelling.

4 files changed, 32 insertions, 15 deletions

diff --git a/sbin/newfs/mkfs.c b/sbin/newfs/mkfs.c
index fe862b5..c4ddef3 100644
--- a/sbin/newfs/mkfs.c
+++ b/sbin/newfs/mkfs.c
@@ -448,6 +448,13 @@ mkfs(struct partition *pp, char *fsys)
 		printf("\twith soft updates\n");
 #	undef B2MBFACTOR
 
+	if (Eflag && !Nflag) {
+		printf("Erasing blocks [%jd...%jd[\n", 
+		    sblock.fs_sblockloc / disk.d_bsize,
+		    sblock.fs_size * sblock.fs_fsize / disk.d_bsize);
+		berase(&disk, sblock.fs_sblockloc / disk.d_bsize,
+		    sblock.fs_size * sblock.fs_fsize - sblock.fs_sblockloc);
+	}
 	/*
 	 * Wipe out old UFS1 superblock(s) if necessary.
 	 */
@@ -466,12 +473,12 @@ mkfs(struct partition *pp, char *fsys)
 	}
 	if (!Nflag)
 		sbwrite(&disk, 0);
-	if (Eflag == 1) {
-		printf("** Exiting on Eflag 1\n");
+	if (Xflag == 1) {
+		printf("** Exiting on Xflag 1\n");
 		exit(0);
 	}
-	if (Eflag == 2)
-		printf("** Leaving BAD MAGIC on Eflag 2\n");
+	if (Xflag == 2)
+		printf("** Leaving BAD MAGIC on Xflag 2\n");
 	else
 		sblock.fs_magic = (Oflag != 1) ? FS_UFS2_MAGIC : FS_UFS1_MAGIC;
 
@@ -529,8 +536,8 @@ mkfs(struct partition *pp, char *fsys)
 		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
 		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
 	}
-	if (Eflag == 3) {
-		printf("** Exiting on Eflag 3\n");
+	if (Xflag == 3) {
+		printf("** Exiting on Xflag 3\n");
 		exit(0);
 	}
 	if (!Nflag)
diff --git a/sbin/newfs/newfs.8 b/sbin/newfs/newfs.8
index 875f915..b55cd34 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 JNUln
+.Op Fl EJNUln
 .Op Fl L Ar volname
 .Op Fl O Ar filesystem-type
 .Op Fl S Ar sector-size
@@ -59,10 +59,6 @@
 The
 .Nm
 utility is used to initialize and clear file systems before first use.
-Before running
-.Nm
-the disk must be labeled using
-.Xr bsdlabel 8 .
 The
 .Nm
 utility builds a file system on the specified special file.
@@ -78,6 +74,14 @@ has numerous options to allow the defaults to be selectively overridden.
 .Pp
 The following options define the general layout policies:
 .Bl -tag -width indent
+.It Fl E
+Erase the content of the disk before making the filesystem.
+The reserved area in front of the superblock (for bootcode) will not be erased.
+
+This is a relevant option for flash based storage devices that use
+wear levelling algorithms.
+
+NB: Erasing may take as long time as writing every sector on the disk.
 .It Fl J
 Enable journaling on the new file system via gjournal.
 .It Fl L Ar volname
diff --git a/sbin/newfs/newfs.c b/sbin/newfs/newfs.c
index f69411c..d5fb66d 100644
--- a/sbin/newfs/newfs.c
+++ b/sbin/newfs/newfs.c
@@ -111,12 +111,13 @@ __FBSDID("$FreeBSD$");
  */
 #define	NFPI		4
 
+int	Eflag;			/* Erase previous disk contents */
 int	Lflag;			/* add a volume label */
 int	Nflag;			/* run without writing file system */
 int	Oflag = 2;		/* file system format (1 => UFS1, 2 => UFS2) */
 int	Rflag;			/* regression test */
 int	Uflag;			/* enable soft updates for file system */
-int	Eflag = 0;		/* exit in middle of newfs for testing */
+int	Xflag = 0;		/* exit in middle of newfs for testing */
 int	Jflag;			/* enable gjournal for file system */
 int	lflag;			/* enable multilabel for file system */
 int	nflag;			/* do not create .snap directory */
@@ -160,10 +161,10 @@ main(int argc, char *argv[])
 
 	reserved = 0;
 	while ((ch = getopt(argc, argv,
-	    "EJL:NO:RS:T:Ua:b:c:d:e:f:g:h:i:lm:no:r:s:")) != -1)
+	    "EJL:NO:RS:T:UXa:b:c:d:e:f:g:h:i:lm:no:r:s:")) != -1)
 		switch (ch) {
 		case 'E':
-			Eflag++;
+			Eflag = 1;
 			break;
 		case 'J':
 			Jflag = 1;
@@ -202,6 +203,9 @@ main(int argc, char *argv[])
 		case 'U':
 			Uflag = 1;
 			break;
+		case 'X':
+			Xflag++;
+			break;
 		case 'a':
 			if ((maxcontig = atoi(optarg)) <= 0)
 				errx(1, "%s: bad maximum contiguous blocks",
@@ -440,6 +444,7 @@ usage()
 	    getprogname(),
 	    " [device-type]");
 	fprintf(stderr, "where fsoptions are:\n");
+	fprintf(stderr, "\t-E Erase previuos disk content\n");
 	fprintf(stderr, "\t-J Enable journaling via gjournal\n");
 	fprintf(stderr, "\t-L volume label to add to superblock\n");
 	fprintf(stderr,
diff --git a/sbin/newfs/newfs.h b/sbin/newfs/newfs.h
index 19e383a..5c428c4 100644
--- a/sbin/newfs/newfs.h
+++ b/sbin/newfs/newfs.h
@@ -43,12 +43,13 @@
 /*
  * variables set up by front end.
  */
+extern int	Eflag;		/* Erase previous disk contents */
 extern int	Lflag;		/* add a volume label */
 extern int	Nflag;		/* run mkfs without writing file system */
 extern int	Oflag;		/* build UFS1 format file system */
 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	Xflag;		/* exit in middle of newfs for testing */
 extern int	Jflag;		/* enable gjournal for file system */
 extern int	lflag;		/* enable multilabel MAC for file system */
 extern int	nflag;		/* do not create .snap directory */