Fixed BOOT_HD_BIAS.

2 files changed, 21 insertions, 11 deletions

diff --git a/sys/i386/boot/biosboot/Makefile b/sys/i386/boot/biosboot/Makefile
index de2f403..d5cb29b 100644
--- a/sys/i386/boot/biosboot/Makefile
+++ b/sys/i386/boot/biosboot/Makefile
@@ -1,4 +1,4 @@
-#	$Id: Makefile,v 1.38 1996/03/08 06:29:05 bde Exp $
+#	$Id: Makefile,v 1.39 1996/04/07 14:27:55 bde Exp $
 #
 
 PROG=	boot
@@ -21,11 +21,17 @@ CFLAGS+=	-DBOOTSEG=${BOOTSEG} -DBOOTSTACK=${BOOTSTACK}
 #CFLAGS+=	-DFORCE_COMCONSOLE
 
 # Bias the conversion from the BIOS drive number to the FreeBSD unit number
-# for hard disks to save typing.  E.g., BOOT_HD_BIAS=1 makes BIOS drive 1
-# correspond to 1:sd(0,a) instead of 1:sd(1,a).
-# This may be useful for people booting in a mixed IDE/SCSI environment
-# (set BOOT_HD_BIAS to the number of IDE drives).
+# for hard disks.  This may be useful for people booting in a mixed IDE/SCSI
+# environment (set BOOT_HD_BIAS to the number of IDE drives).
 #CFLAGS+=	-DBOOT_HD_BIAS=1
+#
+# Details: this only applies if BOOT_HD_BIAS > 0.  If the BIOS drive number
+# for the boot drive is >= BOOT_HD_BIAS, then the boot drive is assumed to
+# be SCSI and have unit number (BIOS_drive_number - BOOT_HD_BIAS).  E.g.,
+# BOOT_HD_BIAS=1 makes BIOS drive 1 correspond to 1:sd(0,a) instead of
+# 1:wd(1,a).  If `sd' is given explicitly, then the drive is assumed to be
+# SCSI and have BIOS drive number (sd_unit_number + BOOT_HD_BIAS).  E.g.,
+# BOOT_HD_BIAS=1 makes sd(0,a) correspond to 1:sd(0,a) instead of 0:sd(0,a).
 
 CLEANFILES+=	boot.nohdr boot.strip boot1 boot2 sizetest
 DPADD=		${LIBC}
diff --git a/sys/i386/boot/biosboot/boot.c b/sys/i386/boot/biosboot/boot.c
index 90a638a..1c4c1c9 100644
--- a/sys/i386/boot/biosboot/boot.c
+++ b/sys/i386/boot/biosboot/boot.c
@@ -24,7 +24,7 @@
  * the rights to redistribute these changes.
  *
  *	from: Mach, [92/04/03  16:51:14  rvb]
- *	$Id: boot.c,v 1.48 1996/04/07 14:28:00 bde Exp $
+ *	$Id: boot.c,v 1.49 1996/05/02 10:43:01 phk Exp $
  */
 
 
@@ -112,14 +112,18 @@ boot(int drive)
 	part = 0;
 #endif
 	if (drive & 0x80) {
-		/*
-		 * Hard drive.  Adjust.  Guess that the FreeBSD unit number
-		 * is the BIOS drive number biased by BOOT_HD_BIAS,
-		 */
+		/* Hard drive.  Adjust. */
 		maj = 0;
 #if BOOT_HD_BIAS > 0
-		if (BOOT_HD_BIAS <= unit)
+		if (unit >= BOOT_HD_BIAS) {
+			/*
+			 * The drive is probably a SCSI drive with a unit
+			 * number BOOT_HD_BIAS less than the BIOS drive
+			 * number.
+			 */
+			maj = 4;
 			unit -= BOOT_HD_BIAS;
+		}
 #endif
 	}