Julian Elischer's disklabel fixes.

19 files changed, 687 insertions, 229 deletions

diff --git a/sys/amd64/amd64/machdep.c b/sys/amd64/amd64/machdep.c
index cfedceb..49dbd47 100644
--- a/sys/amd64/amd64/machdep.c
+++ b/sys/amd64/amd64/machdep.c
@@ -35,7 +35,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)machdep.c	7.4 (Berkeley) 6/3/91
- *	$Id: machdep.c,v 1.80 1994/10/25 08:58:33 davidg Exp $
+ *	$Id: machdep.c,v 1.81 1994/10/26 18:35:02 jkh Exp $
  */
 
 #include "npx.h"
@@ -1563,7 +1563,6 @@ Debugger(const char *msg)
 
 #include <sys/disklabel.h>
 #define b_cylin	b_resid
-#define dkpart(dev)              (minor(dev) & 7)
 /*
  * Determine the size of the transfer, and make sure it is
  * within the boundaries of the partition. Adjust transfer
diff --git a/sys/conf/files.i386 b/sys/conf/files.i386
index 2e76e02..c0cdb8a 100644
--- a/sys/conf/files.i386
+++ b/sys/conf/files.i386
@@ -1,7 +1,7 @@
 # This file tells config what files go into building a kernel,
 # files marked standard are always included.
 #
-#	$Id: files.i386,v 1.54 1994/10/13 20:19:11 sos Exp $
+#	$Id: files.i386,v 1.55 1994/10/26 19:19:12 jkh Exp $
 #
 i386/apm/apm.c			optional	apm	device-driver
 i386/apm/apm_setup.s		optional	apm
@@ -112,6 +112,7 @@ i386/isa/sound/uart6850.c	optional	snd	device-driver
 i386/isa/spkr.c			optional	speaker
 i386/isa/tw.c			optional	tw	device-driver
 i386/isa/ultra14f.c		optional	uha	device-driver
+i386/isa/readMBR.c		standard	
 i386/isa/wd.c			optional	wd	device-driver
 i386/isa/wt.c			optional	wt	device-driver
 i386/isa/pcvt/pcvt_drv.c	optional	vt	device-driver
diff --git a/sys/dev/fdc/fdc.c b/sys/dev/fdc/fdc.c
index a000acf..e06ac4a 100644
--- a/sys/dev/fdc/fdc.c
+++ b/sys/dev/fdc/fdc.c
@@ -40,7 +40,7 @@
  * SUCH DAMAGE.
  *
  *	from:	@(#)fd.c	7.4 (Berkeley) 5/25/91
- *	$Id: fd.c,v 1.36 1994/10/21 16:58:50 joerg Exp $
+ *	$Id: fd.c,v 1.37 1994/10/23 21:27:12 wollman Exp $
  *
  */
 
@@ -1522,7 +1522,7 @@ fdioctl(dev, cmd, addr, flag, p)
 		dl->d_secpercyl = fdt->size / fdt->tracks;
 		dl->d_type = DTYPE_FLOPPY;
 
-		if (readdisklabel(dev, fdstrategy, dl, NULL, 0, 0) == NULL)
+		if (readdisklabel(dev, fdstrategy, dl, NULL, 0) == NULL)
 			error = 0;
 		else
 			error = EINVAL;
@@ -1550,11 +1550,11 @@ fdioctl(dev, cmd, addr, flag, p)
 		dl = (struct disklabel *)addr;
 
 		if ((error =
-		     setdisklabel ((struct disklabel *)buffer, dl, 0, NULL)))
+		     setdisklabel ((struct disklabel *)buffer, dl, 0)))
 			break;
 
 		error = writedisklabel(dev, fdstrategy,
-				       (struct disklabel *)buffer, NULL);
+				       (struct disklabel *)buffer);
 		break;
 
 	case FD_FORM:
diff --git a/sys/dev/mcd/mcd.c b/sys/dev/mcd/mcd.c
index e27f600..a6d4bbb 100644
--- a/sys/dev/mcd/mcd.c
+++ b/sys/dev/mcd/mcd.c
@@ -39,7 +39,7 @@
  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
- *	$Id: mcd.c,v 1.25 1994/09/14 20:28:25 ache Exp $
+ *	$Id: mcd.c,v 1.26 1994/10/23 21:27:29 wollman Exp $
  */
 static char COPYRIGHT[] = "mcd-driver (C)1993 by H.Veit & B.Moore";
 
@@ -483,7 +483,6 @@ MCD_TRACE("ioctl called 0x%x\n",cmd,0,0,0);
 		else {
 			return setdisklabel(&cd->dlabel,
 			    (struct disklabel *) addr,
-			    0,
 			    0);
 		}
 	case DIOCWLABEL:
diff --git a/sys/i386/conf/files.i386 b/sys/i386/conf/files.i386
index 2e76e02..c0cdb8a 100644
--- a/sys/i386/conf/files.i386
+++ b/sys/i386/conf/files.i386
@@ -1,7 +1,7 @@
 # This file tells config what files go into building a kernel,
 # files marked standard are always included.
 #
-#	$Id: files.i386,v 1.54 1994/10/13 20:19:11 sos Exp $
+#	$Id: files.i386,v 1.55 1994/10/26 19:19:12 jkh Exp $
 #
 i386/apm/apm.c			optional	apm	device-driver
 i386/apm/apm_setup.s		optional	apm
@@ -112,6 +112,7 @@ i386/isa/sound/uart6850.c	optional	snd	device-driver
 i386/isa/spkr.c			optional	speaker
 i386/isa/tw.c			optional	tw	device-driver
 i386/isa/ultra14f.c		optional	uha	device-driver
+i386/isa/readMBR.c		standard	
 i386/isa/wd.c			optional	wd	device-driver
 i386/isa/wt.c			optional	wt	device-driver
 i386/isa/pcvt/pcvt_drv.c	optional	vt	device-driver
diff --git a/sys/i386/i386/machdep.c b/sys/i386/i386/machdep.c
index cfedceb..49dbd47 100644
--- a/sys/i386/i386/machdep.c
+++ b/sys/i386/i386/machdep.c
@@ -35,7 +35,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)machdep.c	7.4 (Berkeley) 6/3/91
- *	$Id: machdep.c,v 1.80 1994/10/25 08:58:33 davidg Exp $
+ *	$Id: machdep.c,v 1.81 1994/10/26 18:35:02 jkh Exp $
  */
 
 #include "npx.h"
@@ -1563,7 +1563,6 @@ Debugger(const char *msg)
 
 #include <sys/disklabel.h>
 #define b_cylin	b_resid
-#define dkpart(dev)              (minor(dev) & 7)
 /*
  * Determine the size of the transfer, and make sure it is
  * within the boundaries of the partition. Adjust transfer
diff --git a/sys/i386/isa/fd.c b/sys/i386/isa/fd.c
index a000acf..e06ac4a 100644
--- a/sys/i386/isa/fd.c
+++ b/sys/i386/isa/fd.c
@@ -40,7 +40,7 @@
  * SUCH DAMAGE.
  *
  *	from:	@(#)fd.c	7.4 (Berkeley) 5/25/91
- *	$Id: fd.c,v 1.36 1994/10/21 16:58:50 joerg Exp $
+ *	$Id: fd.c,v 1.37 1994/10/23 21:27:12 wollman Exp $
  *
  */
 
@@ -1522,7 +1522,7 @@ fdioctl(dev, cmd, addr, flag, p)
 		dl->d_secpercyl = fdt->size / fdt->tracks;
 		dl->d_type = DTYPE_FLOPPY;
 
-		if (readdisklabel(dev, fdstrategy, dl, NULL, 0, 0) == NULL)
+		if (readdisklabel(dev, fdstrategy, dl, NULL, 0) == NULL)
 			error = 0;
 		else
 			error = EINVAL;
@@ -1550,11 +1550,11 @@ fdioctl(dev, cmd, addr, flag, p)
 		dl = (struct disklabel *)addr;
 
 		if ((error =
-		     setdisklabel ((struct disklabel *)buffer, dl, 0, NULL)))
+		     setdisklabel ((struct disklabel *)buffer, dl, 0)))
 			break;
 
 		error = writedisklabel(dev, fdstrategy,
-				       (struct disklabel *)buffer, NULL);
+				       (struct disklabel *)buffer);
 		break;
 
 	case FD_FORM:
diff --git a/sys/i386/isa/mcd.c b/sys/i386/isa/mcd.c
index e27f600..a6d4bbb 100644
--- a/sys/i386/isa/mcd.c
+++ b/sys/i386/isa/mcd.c
@@ -39,7 +39,7 @@
  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
- *	$Id: mcd.c,v 1.25 1994/09/14 20:28:25 ache Exp $
+ *	$Id: mcd.c,v 1.26 1994/10/23 21:27:29 wollman Exp $
  */
 static char COPYRIGHT[] = "mcd-driver (C)1993 by H.Veit & B.Moore";
 
@@ -483,7 +483,6 @@ MCD_TRACE("ioctl called 0x%x\n",cmd,0,0,0);
 		else {
 			return setdisklabel(&cd->dlabel,
 			    (struct disklabel *) addr,
-			    0,
 			    0);
 		}
 	case DIOCWLABEL:
diff --git a/sys/i386/isa/readMBR.c b/sys/i386/isa/readMBR.c
new file mode 100644
index 0000000..4165d21
--- /dev/null
+++ b/sys/i386/isa/readMBR.c
@@ -0,0 +1,232 @@
+/*
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE WRITERS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE WRITERS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * written by julian elischer (julian@tfs.com)
+ *
+ *	@(#)readMBR.c	8.5 (tfs) 1/21/94
+ * $Id: readMBR.c,v 1.5 1994/10/17 02:31:33 phk Exp $
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/buf.h>
+#include <sys/disklabel.h>
+
+#define	b_cylinder	b_resid
+
+/*
+ * Attempt to read a machine-type dependent Device partitioning table
+ * In this case a PC BIOS MBR.
+ * Destroys the original disklabel if it finds an MBR, so you'd better
+ * know what you're doing. It assumes that the label you've given it
+ * Is the one that controls the device, so that it can fiddle with it
+ * to make sure it's reading absolute sectors.
+ * On exit:
+ * Leaves the disklabel set up with the various partitions
+ * in the last 4 entries, 
+ * the A partition pointing to the BSD part
+ * the C partition set as the BSD partition, (read the disklabel from there) and
+ * the D partition set as the whole disk for beating up
+ * will also give you a copy of the machine dependent table if you ask..
+ * returns 0 for success,
+ * On failure, restores the disklabel and returns a messages pointer.
+ */
+char *
+readMBRtolabel(dev, strat, lp, dp, cyl)
+	dev_t dev;
+	void (*strat)();
+	register struct disklabel *lp;
+	struct dos_partition *dp;
+	int *cyl;
+{
+	register struct buf *bp;
+	struct disklabel *dlp;
+	struct disklabel labelsave;
+	char *msg = NULL;
+	int i;
+	int pseudopart = 4;     /* we fill in pseudoparts from e through h*/
+	int seenBSD = 0;
+
+	/*
+	 * Save a copy of the disklabel in case we return with an error
+	 */
+	bcopy(lp,&labelsave,sizeof(labelsave));
+
+	/*
+	 * Set the disklabel to some useable partitions in case it's rubbish
+	 */
+        if (lp->d_secperunit == 0)
+                lp->d_secperunit = 0x1fffffff;
+	lp->d_npartitions = 4;
+	for (i=0; i<MAXPARTITIONS; i++) {
+		lp->d_partitions[i].p_offset = 0;
+		lp->d_partitions[i].p_size = 0;
+	}
+	lp->d_partitions[RAWPART].p_size = DOSBBSECTOR + 1; /* start low */
+	strcpy(lp->d_packname,"MBR based label");  /* Watch the length ! */
+
+	/*
+	 * Get a buffer and get ready to read the MBR
+	 */
+	bp = geteblk((int)lp->d_secsize);
+	/* read master boot record */
+	bp->b_dev = makedev(major(dev), dkminor(dkunit(dev), RAWPART));
+	bp->b_blkno = DOSBBSECTOR;
+	bp->b_bcount = lp->d_secsize;
+	bp->b_flags = B_BUSY | B_READ;
+	bp->b_cylinder = DOSBBSECTOR / lp->d_secpercyl;
+	(*strat)(bp);
+
+	/* if successful, wander through dos partition table */
+	if ( biowait(bp)) {
+		msg = "dos partition I/O error";
+		goto bad;
+	} else {
+		/*
+		 * If there seems to be  BIOS bootblock and partition table
+		 * in that block, then try interpret it, otherwise
+		 * give up and use whatever we have synthesised so far
+		 */
+		if ((*(bp->b_un.b_addr + 510) != (char) 0x55)
+		  ||(*(bp->b_un.b_addr + 511) != (char) 0xaa)) {
+			msg = "Disk has no Fdisk partitions";
+			goto bad;
+		}
+
+		if(dp) { /* if they asked for a copy, give it to them */
+			bcopy(bp->b_un.b_addr + DOSPARTOFF, dp,
+				NDOSPART * sizeof(*dp));
+		}
+		dp = (struct dos_partition *)(bp->b_un.b_addr + DOSPARTOFF);
+		/*
+		 * We have a DOS MBR..
+		 * We set up the last 4 partitions in the
+		 * disklabel to reflect the DOS partitions
+		 * In case we never find a disklabel, in which
+		 * case this information will be all we have
+		 * but it might be all we need to access a DOS
+		 * partition.
+		 */
+		for (i = 0; i < NDOSPART; i++, dp++,pseudopart++) {
+		
+		        if (!dp->dp_size)
+				continue;
+		        /*
+		         * Set this DOS part into the disklabel
+		         */
+		        lp->d_partitions[pseudopart].p_size =
+				dp->dp_size;
+		        lp->d_partitions[pseudopart].p_offset =
+				dp->dp_start;
+		
+		        /*
+		         * make sure the D part can hold it all
+		         */
+		        if((dp->dp_start + dp->dp_size)
+		           > lp->d_partitions[3].p_size) {
+				lp->d_partitions[3].p_size
+				        = (dp->dp_start + dp->dp_size);
+		        }
+		
+		        /*
+		         * If we haven't seen a *BSD partition then
+		         * check if this is a valid part..
+		         * if it is it may be the best we are going to
+		         * to see, so take note of it to deduce a
+		         * geometry in case we never find a disklabel.
+		         */
+			switch(dp->dp_typ) {
+			case DOSPTYP_386BSD:
+				/*
+				 * at a pinch we could throw
+				 * a FFS on here
+				 */
+				lp->d_partitions[pseudopart].p_fstype
+						= FS_BSDFFS;
+				/*
+				 * Only get a disklabel from the
+				 * first one we see..
+				 */
+				if (seenBSD == 0) {
+					/*
+					 * If it IS our part, then we
+					 * need sector address for
+					 * SCSI/IDE, cylinder for
+					 * ESDI/ST506/RLL
+					 */
+					seenBSD = 1;
+					*cyl = DPCYL(dp->dp_scyl,
+						dp->dp_ssect);
+	
+					/*
+					 * Note which part we are in (?)
+					 */
+					lp->d_subtype &= ~3;
+					lp->d_subtype |= i & 3;
+					lp->d_subtype
+						|= DSTYPE_INDOSPART;
+
+					/*
+					 * update disklabel with
+					 * details for reading the REAL
+					 * disklabel it it exists
+					 */
+					lp->d_partitions[OURPART].p_size =
+						dp->dp_size;
+					lp->d_partitions[OURPART].p_offset =
+						dp->dp_start;
+				}
+				break;
+			case 0xB7: /* BSDI (?)*//* doubtful */
+				lp->d_partitions[pseudopart].p_fstype
+						= FS_BSDFFS;
+				break;
+			case 1:
+			case 4:
+			case 6:
+			case 0xF2:
+				lp->d_partitions[pseudopart].p_fstype
+						= FS_MSDOS;
+				break;
+			}
+	
+			/*
+			 * Try deduce the geometry, working
+			 * on the principle that  this
+			 * partition PROBABLY ends on a
+			 * cylinder boundary.
+			 * This is really a kludge, but we are
+			 * forced into it by the PC's design.
+			 * If we've seen a 386bsd part,
+			 * believe it and check no further.
+			 */
+			if (seenBSD) continue;
+			lp->d_ntracks = dp->dp_ehd + 1;
+			lp->d_nsectors = DPSECT(dp->dp_esect);
+			lp->d_secpercyl = lp->d_ntracks *
+				lp->d_nsectors;
+		}
+		lp->d_npartitions = 8;
+        }
+	bp->b_flags = B_INVAL | B_AGE;
+	brelse(bp);
+	return 0;
+bad:
+	bcopy(&labelsave,lp,sizeof(labelsave));
+	bp->b_flags = B_INVAL | B_AGE;
+	brelse(bp);
+	return msg;
+}			
+
+
diff --git a/sys/i386/isa/wd.c b/sys/i386/isa/wd.c
index 8cc7460..30c990d 100644
--- a/sys/i386/isa/wd.c
+++ b/sys/i386/isa/wd.c
@@ -37,7 +37,7 @@ static int wdtest = 0;
  * SUCH DAMAGE.
  *
  *	from: @(#)wd.c	7.2 (Berkeley) 5/9/91
- *	$Id: wd.c,v 1.56 1994/10/23 21:27:40 wollman Exp $
+ *	$Id: wd.c,v 1.57 1994/10/27 05:39:12 phk Exp $
  */
 
 /* TODO:
@@ -271,8 +271,6 @@ struct isa_driver wdcdriver = {
 	wdprobe, wdattach, "wdc",
 };
 
-extern char *readdisklabel();
-
 /*
  * Probe for controller.
  */
@@ -993,14 +991,9 @@ wdopen(dev_t dev, int flags, int fmt, struct proc *p)
 		save_label = du->dk_dd;
 		du->dk_dd.d_partitions[WDRAW].p_offset = 0;
 		du->dk_dd.d_partitions[WDRAW].p_size = 0x7fffffff;/* XXX */
-#define WDSTRATEGY	((int (*)(struct buf *)) wdstrategy)	/* XXX */
 		msg = readdisklabel(makewddev(major(dev), lunit, WDRAW),
-				    WDSTRATEGY, &du->dk_dd,
+				    wdstrategy, &du->dk_dd,
 				    du->dk_dospartitions, &du->dk_bad);
-/*
-		msg = readdisklabel(makewddev(major(dev), lunit, WDRAW),
-				WDSTRATEGY, &du->dk_dd);
-*/
 		du->dk_flags &= ~DKFL_LABELLING;
 		if (msg != NULL) {
 			du->dk_dd = save_label;
@@ -1437,8 +1430,7 @@ wdioctl(dev_t dev, int cmd, caddr_t addr, int flag)
 					     du->dk_flags & DKFL_BSDLABEL
 					     ? du->dk_openpart :
 #endif
-					     0,
-					     du->dk_dospartitions);
+					     0);
 		if (error == 0) {
 			du->dk_flags |= DKFL_BSDLABEL;
 			wdwsetctlr(du);	/* XXX - check */
@@ -1463,8 +1455,7 @@ wdioctl(dev_t dev, int cmd, caddr_t addr, int flag)
 					       du->dk_flags & DKFL_BSDLABEL
 					       ? du->dk_openpart :
 #endif
-					       0,
-					       du->dk_dospartitions)) == 0) {
+					       0)) == 0) {
 			int	wlab;
 
 			du->dk_flags |= DKFL_BSDLABEL;
@@ -1474,8 +1465,7 @@ wdioctl(dev_t dev, int cmd, caddr_t addr, int flag)
 			du->dk_openpart |= (1 << 0);	/* XXX */
 			wlab = du->dk_wlabel;
 			du->dk_wlabel = 1;
-			error = writedisklabel(dev, WDSTRATEGY,
-					&du->dk_dd, du->dk_dospartitions);
+			error = writedisklabel(dev, wdstrategy, &du->dk_dd);
 			du->dk_openpart = du->dk_copenpart | du->dk_bopenpart;
 			du->dk_wlabel = wlab;
 		}
@@ -1524,7 +1514,12 @@ wdformat(struct buf *bp)
 {
 
 	bp->b_flags |= B_FORMAT;
-	return (wdstrategy(bp));
+	wdstrategy(bp);
+	/* 
+	 * phk put this here, better that return(wdstrategy(bp));
+	 * XXX
+	 */
+	return -1;
 }
 #endif
 
diff --git a/sys/isa/fd.c b/sys/isa/fd.c
index a000acf..e06ac4a 100644
--- a/sys/isa/fd.c
+++ b/sys/isa/fd.c
@@ -40,7 +40,7 @@
  * SUCH DAMAGE.
  *
  *	from:	@(#)fd.c	7.4 (Berkeley) 5/25/91
- *	$Id: fd.c,v 1.36 1994/10/21 16:58:50 joerg Exp $
+ *	$Id: fd.c,v 1.37 1994/10/23 21:27:12 wollman Exp $
  *
  */
 
@@ -1522,7 +1522,7 @@ fdioctl(dev, cmd, addr, flag, p)
 		dl->d_secpercyl = fdt->size / fdt->tracks;
 		dl->d_type = DTYPE_FLOPPY;
 
-		if (readdisklabel(dev, fdstrategy, dl, NULL, 0, 0) == NULL)
+		if (readdisklabel(dev, fdstrategy, dl, NULL, 0) == NULL)
 			error = 0;
 		else
 			error = EINVAL;
@@ -1550,11 +1550,11 @@ fdioctl(dev, cmd, addr, flag, p)
 		dl = (struct disklabel *)addr;
 
 		if ((error =
-		     setdisklabel ((struct disklabel *)buffer, dl, 0, NULL)))
+		     setdisklabel ((struct disklabel *)buffer, dl, 0)))
 			break;
 
 		error = writedisklabel(dev, fdstrategy,
-				       (struct disklabel *)buffer, NULL);
+				       (struct disklabel *)buffer);
 		break;
 
 	case FD_FORM:
diff --git a/sys/kern/subr_disklabel.c b/sys/kern/subr_disklabel.c
index f116269..4849146 100644
--- a/sys/kern/subr_disklabel.c
+++ b/sys/kern/subr_disklabel.c
@@ -36,17 +36,17 @@
  * SUCH DAMAGE.
  *
  *	@(#)ufs_disksubr.c	8.5 (Berkeley) 1/21/94
- * $Id: ufs_disksubr.c,v 1.4 1994/10/08 06:57:23 phk Exp $
+ * $Id: ufs_disksubr.c,v 1.5 1994/10/17 02:31:33 phk Exp $
  */
 
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/buf.h>
+#include <sys/dkbad.h>
 #include <sys/disklabel.h>
 #include <sys/syslog.h>
 #include <sys/dkbad.h>
 
-int	dkcksum __P((struct disklabel *));
 /*
  * Seek sort for disks.  We depend on the driver which calls us using b_resid
  * as the current cylinder number.
@@ -154,86 +154,53 @@ insert:	bp->b_actf = bq->b_actf;
  * anything required in the strategy routine (e.g., sector size) must be
  * filled in before calling us.  Returns NULL on success and an error
  * string on failure.
+ * If Machine Specific Partitions (MSP) are not found, then it will proceed
+ * as if the BSD partition starts at 0
+ * The MBR on an IBM PC is an example of an MSP.
  */
 char *
 readdisklabel(dev, strat, lp, dp, bdp)
 	dev_t dev;
-	int (*strat)();
+	void (*strat)();
 	register struct disklabel *lp;
 	struct dos_partition *dp;
 	struct dkbad *bdp;
 {
 	register struct buf *bp;
 	struct disklabel *dlp;
+	char *msgMSP = NULL;
 	char *msg = NULL;
-	int dospartoff;
 	int i;
-	int cyl;
+	int cyl = 0;
 
+	/*
+	 * Set up the disklabel as in case there is no MSP.
+	 * We set the BSD part, but don't need to set the
+	 * RAW part, because readMSPtolabel() will reset that
+	 * itself. On return however, if there was no MSP,
+	 * then we will be looking into OUR part to find the label
+	 * and we will want that to start at 0, and have at least SOME length.
+	 */
 	if (lp->d_secperunit == 0)
 		lp->d_secperunit = 0x1fffffff;
-	lp->d_npartitions = 1;
-	if (lp->d_partitions[0].p_size == 0)
-		lp->d_partitions[0].p_size = 0x1fffffff;
-	lp->d_partitions[0].p_offset = 0;
-
-	bp = geteblk((int)lp->d_secsize);
-	/* do dos partitions in the process of getting disklabel? */
-	dospartoff = 0;
-	cyl = LABELSECTOR / lp->d_secpercyl;
-	if (dp) {
-		/* read master boot record */
-		bp->b_dev = dev; 
-		bp->b_blkno = DOSBBSECTOR;
-		bp->b_bcount = lp->d_secsize;
-		bp->b_flags = B_BUSY | B_READ;
-		bp->b_cylinder = DOSBBSECTOR / lp->d_secpercyl;
-		(*strat)(bp);
-
-		/* if successful, wander through dos partition table */
-		if (biowait(bp)) {
-			msg = "dos partition I/O error";
-			goto done;
-		} else {
-			/* XXX how do we check veracity/bounds of this? */
-			bcopy(bp->b_un.b_addr + DOSPARTOFF, dp,
-				NDOSPART * sizeof(*dp));
-			for (i = 0; i < NDOSPART; i++, dp++)
-				/* is this ours? */
-				if (dp->dp_size &&
-					dp->dp_typ == DOSPTYP_386BSD
-					&& dospartoff == 0) {
+	lp->d_npartitions = OURPART + 1;
+	if (lp->d_partitions[OURPART].p_size == 0)
+		lp->d_partitions[OURPART].p_size = 0x100; /*enough for a label*/
+	lp->d_partitions[OURPART].p_offset = 0;
 
-					/* need sector address for SCSI/IDE,
-					   cylinder for ESDI/ST506/RLL */
-					dospartoff = dp->dp_start;
-					cyl = DPCYL(dp->dp_scyl, dp->dp_ssect);
-
-					/* update disklabel with details */
-					lp->d_partitions[0].p_size =
-						dp->dp_size;
-					lp->d_partitions[0].p_offset = 
-						dp->dp_start;
-					lp->d_ntracks = dp->dp_ehd + 1;
-					lp->d_nsectors = DPSECT(dp->dp_esect);
-#ifdef CC_WALL
-/* The next statement looks bogus... i runs int 0..3 ??? */
-					lp->d_subtype |= ((lp->d_subtype & 3)
-							+ i) | DSTYPE_INDOSPART;
-#else /* CC_WALL */
-					lp->d_subtype |= (lp->d_subtype & 3)
-							+ i | DSTYPE_INDOSPART;
-#endif /* CC_WALL */
-					lp->d_secpercyl = lp->d_ntracks *
-						lp->d_nsectors;
-				}
-		}
-			
-	}
+	/*
+	 * Dig out the Dos MSP.. If we get it, all remaining transfers
+	 * will be relative to the base of the BSD part.
+	 */
+	msgMSP = readMSPtolabel(dev, strat, lp, dp, &cyl );
 	
-	/* next, dig out disk label */
-	bp->b_blkno = dospartoff + LABELSECTOR;
-	bp->b_dev = dev; 
+	/*
+	 * next, dig out disk label, relative to either the base of the
+	 * BSD part, or block 0, depending on if an MSP was found.
+	 */
+	bp = geteblk((int)lp->d_secsize);
+	bp->b_blkno = LABELSECTOR;
+	bp->b_dev = makedev(major(dev), dkminor(dkunit(dev), OURPART));
 	bp->b_bcount = lp->d_secsize;
 	bp->b_flags = B_BUSY | B_READ;
 	bp->b_cylinder = cyl;
@@ -256,8 +223,19 @@ readdisklabel(dev, strat, lp, dp, bdp)
 			break;
 		}
 	}
-	if (msg)
+
+	if (msg && msgMSP) {
+		msg = msgMSP;
 		goto done;
+	}
+
+	/*
+	 * Since we had one of the two labels, either one made up from the
+	 * MSP, one found in the FreeBSD-MSP-partitions sector 2, or even
+	 * one in sector 2 absolute on the disk, there is not really an error.
+	 */
+
+	msg = NULL;
 
 	/* obtain bad sector table if requested and present */
 	if (bdp && (lp->d_flags & D_BADSECT)) {
@@ -312,11 +290,20 @@ setdisklabel(olp, nlp, openmask)
 	register i;
 	register struct partition *opp, *npp;
 
+	/*
+	 * Check it is actually a disklabel we are looking at.
+	 */
 	if (nlp->d_magic != DISKMAGIC || nlp->d_magic2 != DISKMAGIC ||
 	    dkcksum(nlp) != 0)
 		return (EINVAL);
+	/*
+	 * For each partition that we think is open,
+	 */
 	while ((i = ffs((long)openmask)) != 0) {
 		i--;
+		/*
+	 	 * Check it is not changing....
+	 	 */
 		openmask &= ~(1 << i);
 		if (nlp->d_npartitions <= i)
 			return (EBUSY);
@@ -327,6 +314,8 @@ setdisklabel(olp, nlp, openmask)
 		/*
 		 * Copy internally-set partition information
 		 * if new label doesn't include it.		XXX
+		 * (If we are using it then we had better stay the same type)
+		 * This is possibly dubious, as someone else noted (XXX)
 		 */
 		if (npp->p_fstype == FS_UNUSED && opp->p_fstype != FS_UNUSED) {
 			npp->p_fstype = opp->p_fstype;
@@ -341,38 +330,100 @@ setdisklabel(olp, nlp, openmask)
 	return (0);
 }
 
-/* encoding of disk minor numbers, should be elsewhere... */
-#define dkunit(dev)		(minor(dev) >> 3)
-#define dkpart(dev)		(minor(dev) & 07)
-#define dkminor(unit, part)	(((unit) << 3) | (part))
-
 /*
  * Write disk label back to device after modification.
+ * For FreeBSD 2.0(x86) this routine will refuse to install a label if
+ * there is no DOS MSP. (this can be changed)
+ *
+ * Assumptions for THIS VERSION:
+ * The given disklabel pointer is actually that which is controlling this
+ * Device, so that by fiddling it, readMSPtolabel() can ensure that
+ * it can read from the MSP if it exists,
+ * This assumption will cease as soon as ther is a better way of ensuring
+ * that a read is done to the whole raw device.
+ * MSP defines a BSD part, label is in block 1 (2nd block) of this
  */
 int
 writedisklabel(dev, strat, lp)
 	dev_t dev;
-	int (*strat)();
+	void (*strat)();
 	register struct disklabel *lp;
 {
-	struct buf *bp;
+	struct buf *bp = NULL;
 	struct disklabel *dlp;
-	int labelpart;
 	int error = 0;
+	struct disklabel label;
+	char *msg;
+	int BSDstart,BSDlen;
+	int cyl; /* dummy arg for readMSPtolabel() */
 
-	labelpart = dkpart(dev);
-	/* XXX this is wrong. But leaving it in is worse. */
-#ifndef __FREEBSD__
-	if (lp->d_partitions[labelpart].p_offset != 0) {
-		if (lp->d_partitions[0].p_offset != 0)
-			return (EXDEV);			/* not quite right */
-		labelpart = 0;
+	/*
+	 * Save the label (better be the real one)
+	 * because we are going to play funny games with the disklabel
+	 * controlling this device..
+	 */
+	bcopy(lp,&label,sizeof(label));
+	/*
+	 * Unlike the read, we will trust the parameters given to us
+	 * about the disk, in the new disklabel but will simply
+	 * force OURPART to start at block 0 as a default in case there is NO
+	 * MSP.
+	 * readMSPtolabel() will reset it to start at the start of the BSD
+	 * part if it exists 
+	 * At this time this is an error contition but I've left support for it
+	 */
+	lp->d_npartitions = OURPART + 1;
+	if (lp->d_partitions[OURPART].p_size == 0)
+		lp->d_partitions[OURPART].p_size = 0x1fffffff;
+	lp->d_partitions[OURPART].p_offset = 0;
+
+	msg = readMSPtolabel(dev, strat, lp, 0, &cyl );
+	/*
+	 * If we want to be able to install without an Machine Specific 
+	 * Partitioning , then
+	 * the failure of readMSPtolabel() should be made non fatal.
+	 */
+	if(msg) {
+		printf("writedisklabel:%s\n",msg);
+		error = ENXIO;
+		goto done;
 	}
-#endif
+	/*
+	 * If we had MSP (no message) but there
+	 * was no BSD part in it
+	 * then balk.. they should use fdisk to make one first or smash it..
+	 * This may just be me being paranoid, but it's my choice for now..
+	 * note we test for !msg, because the test above might be changed
+	 * as a valid option..
+	 */
+	if((!msg) && (!(lp->d_subtype & DSTYPE_INDOSPART))) {
+		printf("writedisklabel: MSP with no BSD part\n");
+	}
+
+	/*
+	 * get all the other bits back from the good new disklabel
+	 * (the user wouldn't try confuse us would he?)
+	 * With the exception of the OURPART which now points to the 
+	 * BSD partition.
+	 */
+	BSDstart = lp->d_partitions[OURPART].p_offset;
+	BSDlen = lp->d_partitions[OURPART].p_size;
+	bcopy(&label,lp,sizeof(label));
+	lp->d_partitions[OURPART].p_offset = BSDstart;
+	lp->d_partitions[OURPART].p_size = BSDlen;
+
 	bp = geteblk((int)lp->d_secsize);
-	bp->b_dev = makedev(major(dev), dkminor(dkunit(dev), labelpart));
+	bp->b_dev = makedev(major(dev), dkminor(dkunit(dev), OURPART));
 	bp->b_blkno = LABELSECTOR;
 	bp->b_bcount = lp->d_secsize;
+#ifdef STUPID
+	/*
+	 * We read the label first to see if it's there,
+	 * in which case we will put ours at the same offset into the block..
+	 * (I think this is stupid [Julian])
+	 * Note that you can't write a label out over a corrupted label!
+	 * (also stupid.. how do you write the first one? by raw writes?)
+	 */
 	bp->b_flags = B_READ;
 	(*strat)(bp);
 	error = biowait(bp);
@@ -384,7 +435,7 @@ writedisklabel(dev, strat, lp)
 	    dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
 		if (dlp->d_magic == DISKMAGIC && dlp->d_magic2 == DISKMAGIC &&
 		    dkcksum(dlp) == 0) {
-			*dlp = *lp;
+			bcopy(&label,dlp,sizeof(label));
 			bp->b_flags = B_WRITE;
 			(*strat)(bp);
 			error = biowait(bp);
@@ -392,15 +443,24 @@ writedisklabel(dev, strat, lp)
 		}
 	}
 	error = ESRCH;
+#else	/* Stupid */
+	dlp = (struct disklabel *)bp->b_data;
+	bcopy(&label,dlp,sizeof(label));
+	bp->b_flags = B_WRITE;
+	(*strat)(bp);
+	error = biowait(bp);
+#endif 	/* Stupid */
 done:
-	brelse(bp);
+	bcopy(&label,lp,sizeof(label)); /* start using the new label again */
+	if(bp)
+		brelse(bp);
 	return (error);
 }
 
 /*
  * Compute checksum for disk label.
  */
-int
+u_int
 dkcksum(lp)
 	register struct disklabel *lp;
 {
diff --git a/sys/scsi/cd.c b/sys/scsi/cd.c
index 9c94bb3..438d047 100644
--- a/sys/scsi/cd.c
+++ b/sys/scsi/cd.c
@@ -14,7 +14,7 @@
  *
  * Ported to run under 386BSD by Julian Elischer (julian@tfs.com) Sept 1992
  *
- *      $Id: cd.c,v 1.26 1994/10/19 00:09:42 wollman Exp $
+ *      $Id: cd.c,v 1.27 1994/10/23 21:27:52 wollman Exp $
  */
 
 #define SPLCD splbio
@@ -677,9 +677,7 @@ cdioctl(dev_t dev, int cmd, caddr_t addr, int flag)
 			error = EBADF;
 		else
 			error = setdisklabel(&cd->disklabel,
-			    (struct disklabel *) addr,
-			    0,
-			    0);
+			    (struct disklabel *) addr, 0);
 		if (error == 0)
 			break;
 
diff --git a/sys/scsi/sd.c b/sys/scsi/sd.c
index 6bfb807..2223b97 100644
--- a/sys/scsi/sd.c
+++ b/sys/scsi/sd.c
@@ -14,7 +14,7 @@
  *
  * Ported to run under 386BSD by Julian Elischer (julian@dialix.oz.au) Sept 1992
  *
- *      $Id: sd.c,v 1.36 1994/10/20 00:08:31 phk Exp $
+ *      $Id: sd.c,v 1.37 1994/10/23 21:27:57 wollman Exp $
  */
 
 #define SPLSD splbio
@@ -67,7 +67,6 @@ int     Debugger(const char *);
 
 #define WHOLE_DISK(unit) ( (unit << UNITSHIFT) + RAW_PART )
 
-extern char *readdisklabel();
 errval	sdgetdisklabel __P((unsigned char unit));
 errval	sd_get_parms __P((int unit, int flags));
 void	sdstrategy __P((struct buf *));
@@ -782,6 +781,10 @@ sdgetdisklabel(unsigned char unit)
 	/*
 	 * Call the generic disklabel extraction routine
 	 */
+	sd->flags |= SDHAVELABEL;	/* chicken and egg problem */
+					/* we need to pretend this disklabel */
+					/* is real before we can read */
+					/* real disklabel */
 	errstring = readdisklabel(makedev(0, (unit << UNITSHIFT) + RAW_PART),
 	    sdstrategy,
 	    &sd->disklabel
@@ -792,10 +795,10 @@ sdgetdisklabel(unsigned char unit)
 #endif
 	    ); 
 	if (errstring) {
+		sd->flags &= ~SDHAVELABEL;	/* not now we don't */
 		printf("sd%d: %s\n", unit, errstring);
 		return ENXIO;
 	}
-	sd->flags |= SDHAVELABEL;	/* WE HAVE IT ALL NOW */
 	return ESUCCESS;
 }
 
diff --git a/sys/sys/disklabel.h b/sys/sys/disklabel.h
index 38738ca..229d52b 100644
--- a/sys/sys/disklabel.h
+++ b/sys/sys/disklabel.h
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)disklabel.h	8.1 (Berkeley) 6/2/93
- * $Id: disklabel.h,v 1.4 1994/08/21 04:41:39 paul Exp $
+ * $Id: disklabel.h,v 1.5 1994/10/20 23:41:57 paul Exp $
  */
 
 #ifndef _SYS_DISKLABEL_H_
@@ -54,6 +54,25 @@
 #ifdef i386
 #define LABELSECTOR	1			/* sector containing label */
 #define LABELOFFSET	0			/* offset of label in sector */
+#define	OURPART		2			/* partition is 'all BSD' */
+#define	RAWPART		3			/* partition is 'all device' */
+#define readMSPtolabel readMBRtolabel
+#endif
+
+#ifndef readMSPtolabel
+#define readMSPtolabel(a,b,c,d,e,)		/* zap calls if irrelevant */
+#endif
+
+#ifdef	tahoe
+#define RAWPART		0
+#endif
+
+#ifndef	RAWPART
+#define	RAWPART		2
+#endif
+
+#ifndef	OURPART
+#define	OURPART		RAWPART			/* by default it's all ours */
 #endif
 
 #ifndef	LABELSECTOR
@@ -358,6 +377,18 @@ extern struct dos_partition dos_partitions[NDOSPART];
 
 #endif /* LOCORE */
 
+#ifdef KERNEL
+u_int	 dkcksum __P((struct disklabel *));
+int	writedisklabel __P((dev_t dev, void (*strat)(), struct disklabel *lp));
+char *	readdisklabel __P((dev_t dev, void (*strat)(), struct disklabel *lp, struct dos_partition *dp, struct dkbad *bdp));
+int	setdisklabel __P((struct disklabel *olp, struct disklabel *nlp, u_long openmask));
+void	disksort __P((struct buf *ap, struct buf *bp));
+void	 diskerr __P((struct buf *, char *, char *, int, int, struct disklabel *));
+#ifdef __i386
+char *	readMBRtolabel __P(( dev_t dev , void (*strat)(), register struct disklabel *lp, struct dos_partition *dp, int *cyl));
+#endif
+#endif
+
 #if !defined(KERNEL) && !defined(LOCORE)
 
 #include <sys/cdefs.h>
@@ -368,4 +399,13 @@ __END_DECLS
 
 #endif
 
+#ifdef __i386
+/* encoding of disk minor numbers, should be elsewhere... */
+#define dkunit(dev)		(minor(dev) >> 3)
+#define dkpart(dev)		(minor(dev) & 07)
+#define dkminor(unit, part)	(((unit) << 3) | (part))
 #endif
+
+#endif
+
+
diff --git a/sys/sys/diskmbr.h b/sys/sys/diskmbr.h
index 38738ca..229d52b 100644
--- a/sys/sys/diskmbr.h
+++ b/sys/sys/diskmbr.h
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)disklabel.h	8.1 (Berkeley) 6/2/93
- * $Id: disklabel.h,v 1.4 1994/08/21 04:41:39 paul Exp $
+ * $Id: disklabel.h,v 1.5 1994/10/20 23:41:57 paul Exp $
  */
 
 #ifndef _SYS_DISKLABEL_H_
@@ -54,6 +54,25 @@
 #ifdef i386
 #define LABELSECTOR	1			/* sector containing label */
 #define LABELOFFSET	0			/* offset of label in sector */
+#define	OURPART		2			/* partition is 'all BSD' */
+#define	RAWPART		3			/* partition is 'all device' */
+#define readMSPtolabel readMBRtolabel
+#endif
+
+#ifndef readMSPtolabel
+#define readMSPtolabel(a,b,c,d,e,)		/* zap calls if irrelevant */
+#endif
+
+#ifdef	tahoe
+#define RAWPART		0
+#endif
+
+#ifndef	RAWPART
+#define	RAWPART		2
+#endif
+
+#ifndef	OURPART
+#define	OURPART		RAWPART			/* by default it's all ours */
 #endif
 
 #ifndef	LABELSECTOR
@@ -358,6 +377,18 @@ extern struct dos_partition dos_partitions[NDOSPART];
 
 #endif /* LOCORE */
 
+#ifdef KERNEL
+u_int	 dkcksum __P((struct disklabel *));
+int	writedisklabel __P((dev_t dev, void (*strat)(), struct disklabel *lp));
+char *	readdisklabel __P((dev_t dev, void (*strat)(), struct disklabel *lp, struct dos_partition *dp, struct dkbad *bdp));
+int	setdisklabel __P((struct disklabel *olp, struct disklabel *nlp, u_long openmask));
+void	disksort __P((struct buf *ap, struct buf *bp));
+void	 diskerr __P((struct buf *, char *, char *, int, int, struct disklabel *));
+#ifdef __i386
+char *	readMBRtolabel __P(( dev_t dev , void (*strat)(), register struct disklabel *lp, struct dos_partition *dp, int *cyl));
+#endif
+#endif
+
 #if !defined(KERNEL) && !defined(LOCORE)
 
 #include <sys/cdefs.h>
@@ -368,4 +399,13 @@ __END_DECLS
 
 #endif
 
+#ifdef __i386
+/* encoding of disk minor numbers, should be elsewhere... */
+#define dkunit(dev)		(minor(dev) >> 3)
+#define dkpart(dev)		(minor(dev) & 07)
+#define dkminor(unit, part)	(((unit) << 3) | (part))
 #endif
+
+#endif
+
+
diff --git a/sys/sys/diskpc98.h b/sys/sys/diskpc98.h
index 38738ca..229d52b 100644
--- a/sys/sys/diskpc98.h
+++ b/sys/sys/diskpc98.h
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)disklabel.h	8.1 (Berkeley) 6/2/93
- * $Id: disklabel.h,v 1.4 1994/08/21 04:41:39 paul Exp $
+ * $Id: disklabel.h,v 1.5 1994/10/20 23:41:57 paul Exp $
  */
 
 #ifndef _SYS_DISKLABEL_H_
@@ -54,6 +54,25 @@
 #ifdef i386
 #define LABELSECTOR	1			/* sector containing label */
 #define LABELOFFSET	0			/* offset of label in sector */
+#define	OURPART		2			/* partition is 'all BSD' */
+#define	RAWPART		3			/* partition is 'all device' */
+#define readMSPtolabel readMBRtolabel
+#endif
+
+#ifndef readMSPtolabel
+#define readMSPtolabel(a,b,c,d,e,)		/* zap calls if irrelevant */
+#endif
+
+#ifdef	tahoe
+#define RAWPART		0
+#endif
+
+#ifndef	RAWPART
+#define	RAWPART		2
+#endif
+
+#ifndef	OURPART
+#define	OURPART		RAWPART			/* by default it's all ours */
 #endif
 
 #ifndef	LABELSECTOR
@@ -358,6 +377,18 @@ extern struct dos_partition dos_partitions[NDOSPART];
 
 #endif /* LOCORE */
 
+#ifdef KERNEL
+u_int	 dkcksum __P((struct disklabel *));
+int	writedisklabel __P((dev_t dev, void (*strat)(), struct disklabel *lp));
+char *	readdisklabel __P((dev_t dev, void (*strat)(), struct disklabel *lp, struct dos_partition *dp, struct dkbad *bdp));
+int	setdisklabel __P((struct disklabel *olp, struct disklabel *nlp, u_long openmask));
+void	disksort __P((struct buf *ap, struct buf *bp));
+void	 diskerr __P((struct buf *, char *, char *, int, int, struct disklabel *));
+#ifdef __i386
+char *	readMBRtolabel __P(( dev_t dev , void (*strat)(), register struct disklabel *lp, struct dos_partition *dp, int *cyl));
+#endif
+#endif
+
 #if !defined(KERNEL) && !defined(LOCORE)
 
 #include <sys/cdefs.h>
@@ -368,4 +399,13 @@ __END_DECLS
 
 #endif
 
+#ifdef __i386
+/* encoding of disk minor numbers, should be elsewhere... */
+#define dkunit(dev)		(minor(dev) >> 3)
+#define dkpart(dev)		(minor(dev) & 07)
+#define dkminor(unit, part)	(((unit) << 3) | (part))
 #endif
+
+#endif
+
+
diff --git a/sys/ufs/ufs/ufs_disksubr.c b/sys/ufs/ufs/ufs_disksubr.c
index f116269..4849146 100644
--- a/sys/ufs/ufs/ufs_disksubr.c
+++ b/sys/ufs/ufs/ufs_disksubr.c
@@ -36,17 +36,17 @@
  * SUCH DAMAGE.
  *
  *	@(#)ufs_disksubr.c	8.5 (Berkeley) 1/21/94
- * $Id: ufs_disksubr.c,v 1.4 1994/10/08 06:57:23 phk Exp $
+ * $Id: ufs_disksubr.c,v 1.5 1994/10/17 02:31:33 phk Exp $
  */
 
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/buf.h>
+#include <sys/dkbad.h>
 #include <sys/disklabel.h>
 #include <sys/syslog.h>
 #include <sys/dkbad.h>
 
-int	dkcksum __P((struct disklabel *));
 /*
  * Seek sort for disks.  We depend on the driver which calls us using b_resid
  * as the current cylinder number.
@@ -154,86 +154,53 @@ insert:	bp->b_actf = bq->b_actf;
  * anything required in the strategy routine (e.g., sector size) must be
  * filled in before calling us.  Returns NULL on success and an error
  * string on failure.
+ * If Machine Specific Partitions (MSP) are not found, then it will proceed
+ * as if the BSD partition starts at 0
+ * The MBR on an IBM PC is an example of an MSP.
  */
 char *
 readdisklabel(dev, strat, lp, dp, bdp)
 	dev_t dev;
-	int (*strat)();
+	void (*strat)();
 	register struct disklabel *lp;
 	struct dos_partition *dp;
 	struct dkbad *bdp;
 {
 	register struct buf *bp;
 	struct disklabel *dlp;
+	char *msgMSP = NULL;
 	char *msg = NULL;
-	int dospartoff;
 	int i;
-	int cyl;
+	int cyl = 0;
 
+	/*
+	 * Set up the disklabel as in case there is no MSP.
+	 * We set the BSD part, but don't need to set the
+	 * RAW part, because readMSPtolabel() will reset that
+	 * itself. On return however, if there was no MSP,
+	 * then we will be looking into OUR part to find the label
+	 * and we will want that to start at 0, and have at least SOME length.
+	 */
 	if (lp->d_secperunit == 0)
 		lp->d_secperunit = 0x1fffffff;
-	lp->d_npartitions = 1;
-	if (lp->d_partitions[0].p_size == 0)
-		lp->d_partitions[0].p_size = 0x1fffffff;
-	lp->d_partitions[0].p_offset = 0;
-
-	bp = geteblk((int)lp->d_secsize);
-	/* do dos partitions in the process of getting disklabel? */
-	dospartoff = 0;
-	cyl = LABELSECTOR / lp->d_secpercyl;
-	if (dp) {
-		/* read master boot record */
-		bp->b_dev = dev; 
-		bp->b_blkno = DOSBBSECTOR;
-		bp->b_bcount = lp->d_secsize;
-		bp->b_flags = B_BUSY | B_READ;
-		bp->b_cylinder = DOSBBSECTOR / lp->d_secpercyl;
-		(*strat)(bp);
-
-		/* if successful, wander through dos partition table */
-		if (biowait(bp)) {
-			msg = "dos partition I/O error";
-			goto done;
-		} else {
-			/* XXX how do we check veracity/bounds of this? */
-			bcopy(bp->b_un.b_addr + DOSPARTOFF, dp,
-				NDOSPART * sizeof(*dp));
-			for (i = 0; i < NDOSPART; i++, dp++)
-				/* is this ours? */
-				if (dp->dp_size &&
-					dp->dp_typ == DOSPTYP_386BSD
-					&& dospartoff == 0) {
+	lp->d_npartitions = OURPART + 1;
+	if (lp->d_partitions[OURPART].p_size == 0)
+		lp->d_partitions[OURPART].p_size = 0x100; /*enough for a label*/
+	lp->d_partitions[OURPART].p_offset = 0;
 
-					/* need sector address for SCSI/IDE,
-					   cylinder for ESDI/ST506/RLL */
-					dospartoff = dp->dp_start;
-					cyl = DPCYL(dp->dp_scyl, dp->dp_ssect);
-
-					/* update disklabel with details */
-					lp->d_partitions[0].p_size =
-						dp->dp_size;
-					lp->d_partitions[0].p_offset = 
-						dp->dp_start;
-					lp->d_ntracks = dp->dp_ehd + 1;
-					lp->d_nsectors = DPSECT(dp->dp_esect);
-#ifdef CC_WALL
-/* The next statement looks bogus... i runs int 0..3 ??? */
-					lp->d_subtype |= ((lp->d_subtype & 3)
-							+ i) | DSTYPE_INDOSPART;
-#else /* CC_WALL */
-					lp->d_subtype |= (lp->d_subtype & 3)
-							+ i | DSTYPE_INDOSPART;
-#endif /* CC_WALL */
-					lp->d_secpercyl = lp->d_ntracks *
-						lp->d_nsectors;
-				}
-		}
-			
-	}
+	/*
+	 * Dig out the Dos MSP.. If we get it, all remaining transfers
+	 * will be relative to the base of the BSD part.
+	 */
+	msgMSP = readMSPtolabel(dev, strat, lp, dp, &cyl );
 	
-	/* next, dig out disk label */
-	bp->b_blkno = dospartoff + LABELSECTOR;
-	bp->b_dev = dev; 
+	/*
+	 * next, dig out disk label, relative to either the base of the
+	 * BSD part, or block 0, depending on if an MSP was found.
+	 */
+	bp = geteblk((int)lp->d_secsize);
+	bp->b_blkno = LABELSECTOR;
+	bp->b_dev = makedev(major(dev), dkminor(dkunit(dev), OURPART));
 	bp->b_bcount = lp->d_secsize;
 	bp->b_flags = B_BUSY | B_READ;
 	bp->b_cylinder = cyl;
@@ -256,8 +223,19 @@ readdisklabel(dev, strat, lp, dp, bdp)
 			break;
 		}
 	}
-	if (msg)
+
+	if (msg && msgMSP) {
+		msg = msgMSP;
 		goto done;
+	}
+
+	/*
+	 * Since we had one of the two labels, either one made up from the
+	 * MSP, one found in the FreeBSD-MSP-partitions sector 2, or even
+	 * one in sector 2 absolute on the disk, there is not really an error.
+	 */
+
+	msg = NULL;
 
 	/* obtain bad sector table if requested and present */
 	if (bdp && (lp->d_flags & D_BADSECT)) {
@@ -312,11 +290,20 @@ setdisklabel(olp, nlp, openmask)
 	register i;
 	register struct partition *opp, *npp;
 
+	/*
+	 * Check it is actually a disklabel we are looking at.
+	 */
 	if (nlp->d_magic != DISKMAGIC || nlp->d_magic2 != DISKMAGIC ||
 	    dkcksum(nlp) != 0)
 		return (EINVAL);
+	/*
+	 * For each partition that we think is open,
+	 */
 	while ((i = ffs((long)openmask)) != 0) {
 		i--;
+		/*
+	 	 * Check it is not changing....
+	 	 */
 		openmask &= ~(1 << i);
 		if (nlp->d_npartitions <= i)
 			return (EBUSY);
@@ -327,6 +314,8 @@ setdisklabel(olp, nlp, openmask)
 		/*
 		 * Copy internally-set partition information
 		 * if new label doesn't include it.		XXX
+		 * (If we are using it then we had better stay the same type)
+		 * This is possibly dubious, as someone else noted (XXX)
 		 */
 		if (npp->p_fstype == FS_UNUSED && opp->p_fstype != FS_UNUSED) {
 			npp->p_fstype = opp->p_fstype;
@@ -341,38 +330,100 @@ setdisklabel(olp, nlp, openmask)
 	return (0);
 }
 
-/* encoding of disk minor numbers, should be elsewhere... */
-#define dkunit(dev)		(minor(dev) >> 3)
-#define dkpart(dev)		(minor(dev) & 07)
-#define dkminor(unit, part)	(((unit) << 3) | (part))
-
 /*
  * Write disk label back to device after modification.
+ * For FreeBSD 2.0(x86) this routine will refuse to install a label if
+ * there is no DOS MSP. (this can be changed)
+ *
+ * Assumptions for THIS VERSION:
+ * The given disklabel pointer is actually that which is controlling this
+ * Device, so that by fiddling it, readMSPtolabel() can ensure that
+ * it can read from the MSP if it exists,
+ * This assumption will cease as soon as ther is a better way of ensuring
+ * that a read is done to the whole raw device.
+ * MSP defines a BSD part, label is in block 1 (2nd block) of this
  */
 int
 writedisklabel(dev, strat, lp)
 	dev_t dev;
-	int (*strat)();
+	void (*strat)();
 	register struct disklabel *lp;
 {
-	struct buf *bp;
+	struct buf *bp = NULL;
 	struct disklabel *dlp;
-	int labelpart;
 	int error = 0;
+	struct disklabel label;
+	char *msg;
+	int BSDstart,BSDlen;
+	int cyl; /* dummy arg for readMSPtolabel() */
 
-	labelpart = dkpart(dev);
-	/* XXX this is wrong. But leaving it in is worse. */
-#ifndef __FREEBSD__
-	if (lp->d_partitions[labelpart].p_offset != 0) {
-		if (lp->d_partitions[0].p_offset != 0)
-			return (EXDEV);			/* not quite right */
-		labelpart = 0;
+	/*
+	 * Save the label (better be the real one)
+	 * because we are going to play funny games with the disklabel
+	 * controlling this device..
+	 */
+	bcopy(lp,&label,sizeof(label));
+	/*
+	 * Unlike the read, we will trust the parameters given to us
+	 * about the disk, in the new disklabel but will simply
+	 * force OURPART to start at block 0 as a default in case there is NO
+	 * MSP.
+	 * readMSPtolabel() will reset it to start at the start of the BSD
+	 * part if it exists 
+	 * At this time this is an error contition but I've left support for it
+	 */
+	lp->d_npartitions = OURPART + 1;
+	if (lp->d_partitions[OURPART].p_size == 0)
+		lp->d_partitions[OURPART].p_size = 0x1fffffff;
+	lp->d_partitions[OURPART].p_offset = 0;
+
+	msg = readMSPtolabel(dev, strat, lp, 0, &cyl );
+	/*
+	 * If we want to be able to install without an Machine Specific 
+	 * Partitioning , then
+	 * the failure of readMSPtolabel() should be made non fatal.
+	 */
+	if(msg) {
+		printf("writedisklabel:%s\n",msg);
+		error = ENXIO;
+		goto done;
 	}
-#endif
+	/*
+	 * If we had MSP (no message) but there
+	 * was no BSD part in it
+	 * then balk.. they should use fdisk to make one first or smash it..
+	 * This may just be me being paranoid, but it's my choice for now..
+	 * note we test for !msg, because the test above might be changed
+	 * as a valid option..
+	 */
+	if((!msg) && (!(lp->d_subtype & DSTYPE_INDOSPART))) {
+		printf("writedisklabel: MSP with no BSD part\n");
+	}
+
+	/*
+	 * get all the other bits back from the good new disklabel
+	 * (the user wouldn't try confuse us would he?)
+	 * With the exception of the OURPART which now points to the 
+	 * BSD partition.
+	 */
+	BSDstart = lp->d_partitions[OURPART].p_offset;
+	BSDlen = lp->d_partitions[OURPART].p_size;
+	bcopy(&label,lp,sizeof(label));
+	lp->d_partitions[OURPART].p_offset = BSDstart;
+	lp->d_partitions[OURPART].p_size = BSDlen;
+
 	bp = geteblk((int)lp->d_secsize);
-	bp->b_dev = makedev(major(dev), dkminor(dkunit(dev), labelpart));
+	bp->b_dev = makedev(major(dev), dkminor(dkunit(dev), OURPART));
 	bp->b_blkno = LABELSECTOR;
 	bp->b_bcount = lp->d_secsize;
+#ifdef STUPID
+	/*
+	 * We read the label first to see if it's there,
+	 * in which case we will put ours at the same offset into the block..
+	 * (I think this is stupid [Julian])
+	 * Note that you can't write a label out over a corrupted label!
+	 * (also stupid.. how do you write the first one? by raw writes?)
+	 */
 	bp->b_flags = B_READ;
 	(*strat)(bp);
 	error = biowait(bp);
@@ -384,7 +435,7 @@ writedisklabel(dev, strat, lp)
 	    dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
 		if (dlp->d_magic == DISKMAGIC && dlp->d_magic2 == DISKMAGIC &&
 		    dkcksum(dlp) == 0) {
-			*dlp = *lp;
+			bcopy(&label,dlp,sizeof(label));
 			bp->b_flags = B_WRITE;
 			(*strat)(bp);
 			error = biowait(bp);
@@ -392,15 +443,24 @@ writedisklabel(dev, strat, lp)
 		}
 	}
 	error = ESRCH;
+#else	/* Stupid */
+	dlp = (struct disklabel *)bp->b_data;
+	bcopy(&label,dlp,sizeof(label));
+	bp->b_flags = B_WRITE;
+	(*strat)(bp);
+	error = biowait(bp);
+#endif 	/* Stupid */
 done:
-	brelse(bp);
+	bcopy(&label,lp,sizeof(label)); /* start using the new label again */
+	if(bp)
+		brelse(bp);
 	return (error);
 }
 
 /*
  * Compute checksum for disk label.
  */
-int
+u_int
 dkcksum(lp)
 	register struct disklabel *lp;
 {
diff --git a/sys/ufs/ufs/ufs_extern.h b/sys/ufs/ufs/ufs_extern.h
index 8370ecf..7e62140 100644
--- a/sys/ufs/ufs/ufs_extern.h
+++ b/sys/ufs/ufs/ufs_extern.h
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)ufs_extern.h	8.3 (Berkeley) 4/16/94
- * $Id: ufs_extern.h,v 1.3 1994/08/21 07:16:17 paul Exp $
+ * $Id: ufs_extern.h,v 1.4 1994/09/22 19:38:40 wollman Exp $
  */
 
 #ifndef _UFS_UFS_UFS_EXTERN_H_
@@ -54,14 +54,6 @@ struct vnode;
 struct ufs_args;
 
 __BEGIN_DECLS
-void	 diskerr
-	    __P((struct buf *, char *, char *, int, int, struct disklabel *));
-void	 disksort __P((struct buf *, struct buf *));
-u_int	 dkcksum __P((struct disklabel *));
-char	*readdisklabel __P((dev_t, int (*)(), struct disklabel *));
-int	 setdisklabel __P((struct disklabel *, struct disklabel *, u_long));
-int	 writedisklabel __P((dev_t, int (*)(), struct disklabel *));
-
 int	 ufs_abortop __P((struct vop_abortop_args *));
 int	 ufs_access __P((struct vop_access_args *));
 int	 ufs_advlock __P((struct vop_advlock_args *));