Retire the "-N" and "-W" options which implemented write-protection

for the disklabel:  This facility is OBE.

First of all, we cannot sensibly implement this in a properly stacked
environment.

Second, if we did, it would confuse the heck out of users who
wouldn't be able to "start from scratch" by dd(8)'ing /dev/zero
onto /dev/da0.

Third, the offered protection is not comprehensive: no other software
would respect it.

Fourth and finally, the disklabel is already protected against
tampering if it controls open partitions.

Uselessness of these options discussed with:	peter

2 files changed, 3 insertions, 49 deletions

diff --git a/sbin/bsdlabel/bsdlabel.8 b/sbin/bsdlabel/bsdlabel.8
index 1e908c29cf46..b3df66e06436 100644
--- a/sbin/bsdlabel/bsdlabel.8
+++ b/sbin/bsdlabel/bsdlabel.8
@@ -61,9 +61,6 @@
 .Op Fl r
 .Op Fl n
 .Ar disk Ar protofile
-.Nm
-.Op Fl NW
-.Ar disk
 .Pp
 .Nm
 .Fl B
@@ -311,27 +308,6 @@ If
 is used, no data will be written to the device, and instead the
 disklabel that would have been written will be printed to stdout.  This is
 useful to see how a partitioning scheme will work out for a specific disk.
-.Ss Enabling and disabling writing to the disk label area
-.Pp
-By default, it is not possible to write to the disk label area at the beginning
-of a disk.  The disk driver arranges for
-.Xr write 2
-and similar system calls
-to return
-.Er EROFS
-on any attempt to do so.  If you need
-to write to this area (for example, to obliterate the label), use the form
-.Pp
-.Nm
-.Fl W
-.Ar disk
-.Pp
-To disallow writing to the label area after previously allowing it, use the
-command
-.Pp
-.Nm
-.Fl N
-.Ar disk
 .Ss Installing bootstraps
 .Pp
 The final three forms of
diff --git a/sbin/bsdlabel/bsdlabel.c b/sbin/bsdlabel/bsdlabel.c
index bbcf0d08ed2c..bcb721cb4cee 100644
--- a/sbin/bsdlabel/bsdlabel.c
+++ b/sbin/bsdlabel/bsdlabel.c
@@ -163,20 +163,20 @@ char	boot1[MAXPATHLEN];
 #endif
 
 enum	{
-	UNSPEC, EDIT, NOWRITE, READ, RESTORE, WRITE, WRITEABLE, WRITEBOOT
+	UNSPEC, EDIT, READ, RESTORE, WRITE, WRITEBOOT
 } op = UNSPEC;
 
 int	rflag;
 int	disable_write;   /* set to disable writing to disk label */
 
-#define OPTIONS	"BNRWb:enrs:w"
+#define OPTIONS	"BRb:enrs:w"
 
 int
 main(int argc, char *argv[])
 {
 	struct disklabel *lp;
 	FILE *t;
-	int ch, f = 0, flag, error = 0;
+	int ch, f = 0, error = 0;
 	char *name = 0;
 
 	while ((ch = getopt(argc, argv, OPTIONS)) != -1)
@@ -194,11 +194,6 @@ main(int argc, char *argv[])
 				break;
 #endif
 #endif
-			case 'N':
-				if (op != UNSPEC)
-					usage();
-				op = NOWRITE;
-				break;
 			case 'n':
 				disable_write = 1;
 				break;
@@ -207,11 +202,6 @@ main(int argc, char *argv[])
 					usage();
 				op = RESTORE;
 				break;
-			case 'W':
-				if (op != UNSPEC)
-					usage();
-				op = WRITEABLE;
-				break;
 			case 'e':
 				if (op != UNSPEC)
 					usage();
@@ -276,12 +266,6 @@ main(int argc, char *argv[])
 		error = edit(lp, f);
 		break;
 
-	case NOWRITE:
-		flag = 0;
-		if (ioctl(f, DIOCWLABEL, (char *)&flag) < 0)
-			err(4, "ioctl DIOCWLABEL");
-		break;
-
 	case READ:
 		if (argc != 1)
 			usage();
@@ -330,12 +314,6 @@ main(int argc, char *argv[])
 			error = writelabel(f, bootarea, lp);
 		break;
 
-	case WRITEABLE:
-		flag = 1;
-		if (ioctl(f, DIOCWLABEL, (char *)&flag) < 0)
-			err(4, "ioctl DIOCWLABEL");
-		break;
-
 #if NUMBOOT > 0
 	case WRITEBOOT:
 	{