No need to check for DTYPE_FLOPPY. If there is neither a GPT nor

an MBR then install biosboot in sector 0.

Without the check for DTYPE_FLOPPY there is no need for
FSDISKTYPE=floppy3 and therefore flip the last two Makefiles to
the "echo '/ *' | disklabel -wAT-" idiom.

Feedback/fix from kn@

diff --git a/distrib/amd64/ramdiskA/Makefile b/distrib/amd64/ramdiskA/Makefile
index b4e5a95..c060ece 100644 (file)
--- a/distrib/amd64/ramdiskA/Makefile
+++ b/distrib/amd64/ramdiskA/Makefile
@@ -1,8 +1,7 @@
-#      $OpenBSD: Makefile,v 1.20 2023/04/28 18:14:59 krw Exp $
+#      $OpenBSD: Makefile,v 1.21 2023/06/11 14:00:04 krw Exp $
 
 FS=            floppy${OSrev}.img
 FSSIZE=                2880
-FSDISKTYPE=    floppy3
 MOUNT_POINT=   /mnt
 MTREE=         ${UTILS}/mtree.conf
 RAMDISK=       RAMDISK
@@ -17,7 +16,7 @@ all: ${FS}
 ${FS}: bsd.gz
        dd if=/dev/zero of=${FS} bs=512 count=${FSSIZE}
        vnconfig -v ${FS} > vnd
-       disklabel -w `cat vnd` ${FSDISKTYPE}
+       echo '/ *' | disklabel -wAT- `cat vnd`
        newfs -O 1 -m 0 -o space -i 524288 -c ${FSSIZE} -b 4096 -f 512 /dev/r`cat vnd`a
        mount /dev/`cat vnd`a ${MOUNT_POINT}
        objcopy -S -R .comment ${DESTDIR}/usr/mdec/fdboot ${.OBJDIR}/boot

diff --git a/distrib/i386/ramdisk/Makefile b/distrib/i386/ramdisk/Makefile
index db48815..46321bb 100644 (file)
--- a/distrib/i386/ramdisk/Makefile
+++ b/distrib/i386/ramdisk/Makefile
@@ -1,8 +1,7 @@
-#      $OpenBSD: Makefile,v 1.21 2023/04/28 18:14:59 krw Exp $
+#      $OpenBSD: Makefile,v 1.22 2023/06/11 14:00:04 krw Exp $
 
 FS=            floppy${OSrev}.img
 FSSIZE=                2880
-FSDISKTYPE=    floppy3
 MOUNT_POINT=   /mnt
 MTREE=         ${UTILS}/mtree.conf
 RAMDISK=       RAMDISK
@@ -15,7 +14,7 @@ all: ${FS}
 ${FS}: bsd.gz
        dd if=/dev/zero of=${FS} bs=512 count=${FSSIZE}
        vnconfig -v ${FS} > vnd
-       disklabel -w `cat vnd` ${FSDISKTYPE}
+       echo '/ *' | disklabel -wAT- `cat vnd`
        newfs -O 1 -m 0 -o space -i 524288 -c ${FSSIZE} -b 4096 -f 512 /dev/r`cat vnd`a
        mount /dev/`cat vnd`a ${MOUNT_POINT}
        objcopy -S -R .comment ${DESTDIR}/usr/mdec/fdboot ${.OBJDIR}/boot

diff --git a/usr.sbin/installboot/i386_installboot.c b/usr.sbin/installboot/i386_installboot.c
index 1105301..277ef92 100644 (file)
--- a/usr.sbin/installboot/i386_installboot.c
+++ b/usr.sbin/installboot/i386_installboot.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: i386_installboot.c,v 1.45 2023/04/26 18:04:21 kn Exp $        */
+/*     $OpenBSD: i386_installboot.c,v 1.46 2023/06/11 14:00:04 krw Exp $       */
 /*     $NetBSD: installboot.c,v 1.5 1995/11/17 23:23:50 gwr Exp $ */
 
 /*
@@ -196,7 +196,7 @@ write_bootblocks(int devfd, char *dev, struct disklabel *dl)
 {
        struct stat     sb;
        u_int8_t        *secbuf;
-       u_int           start = 0;
+       u_int           start;
 
        /* Write patched proto bootblock(s) into the superblock. */
        if (fstat(devfd, &sb) == -1)
@@ -214,18 +214,15 @@ write_bootblocks(int devfd, char *dev, struct disklabel *dl)
        }
 
        /*
-        * Find OpenBSD partition. Floppies are special, getting an
-        * everything-in-one /boot starting at sector 0.
+        * Find bootstrap sector.
         */
-       if (dl->d_type != DTYPE_FLOPPY) {
-               start = findopenbsd(devfd, dl);
-               if (start == (u_int)-1)
-                       errx(1, "no OpenBSD partition");
-       }
-
-       if (verbose)
+       start = findopenbsd(devfd, dl);
+       if (verbose) {
+               if (start == 0)
+                       fprintf(stderr, "no MBR, ");
                fprintf(stderr, "%s will be written at sector %u\n",
                    stage1, start);
+       }
 
        if (start + (blksize / dl->d_secsize) > BOOTBIOS_MAXSEC)
                warnx("%s extends beyond sector %u. OpenBSD might not boot.",
@@ -437,6 +434,12 @@ rmdir:
                exit(1);
 }
 
+/*
+ * a) For media w/o an MBR use sector 0.
+ * b) For media with an MBR and an OpenBSD (A6) partition use the first
+ *    sector of the OpenBSD partition.
+ * c) For media with an MBR and no OpenBSD partition error out.
+ */
 u_int
 findopenbsd(int devfd, struct disklabel *dl)
 {
@@ -453,7 +456,7 @@ again:
                if (verbose)
                        fprintf(stderr, "Traversed more than %d Extended Boot "
                            "Records (EBRs)\n", DOS_MAXEBR);
-               return ((u_int)-1);
+               goto done;
        }
 
        if (verbose)
@@ -469,9 +472,12 @@ again:
        bcopy(secbuf, &mbr, sizeof(mbr));
        free(secbuf);
 
-       if (mbr.dmbr_sign != DOSMBR_SIGNATURE)
+       if (mbr.dmbr_sign != DOSMBR_SIGNATURE) {
+               if (mbroff == DOSBBSECTOR)
+                       return 0;
                errx(1, "invalid boot record signature (0x%04X) @ sector %u",
                    mbr.dmbr_sign, mbroff);
+       }
 
        nextebr = 0;
        for (i = 0; i < NDOSPART; i++) {
@@ -505,7 +511,8 @@ again:
                goto again;
        }
 
-       return ((u_int)-1);
+ done:
+       errx(1, "no OpenBSD partition");
 }
 
 /*