From 1d09a9b99983e4e80915bd59a98e91778c6a0645 Mon Sep 17 00:00:00 2001
From: Pawel Jakub Dawidek <pjd@FreeBSD.org>
Date: Fri, 17 Sep 2010 22:59:15 +0000
Subject: [PATCH] Before VirtualBox is fixed, mark with #ifdef what has to be
 done to make it possible to boot from ZFS RAIDZ for example from within
 VirtualBox. The problem with VirtualBox is that its BIOS reports only one
 disk present. If we choose to ignore this report, we can find all the disks
 available. We can't have this work-around to be turned on by default, because
 some broken BIOSes report true when it comes to number of disks, but present
 the same disk multiple times.

---
 sys/boot/i386/libi386/biosdisk.c | 4 +++-
 sys/boot/i386/zfsboot/zfsboot.c  | 9 +++++++--
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/sys/boot/i386/libi386/biosdisk.c b/sys/boot/i386/libi386/biosdisk.c
index cf0b03353ea7..a67a7ef9a882 100644
--- a/sys/boot/i386/libi386/biosdisk.c
+++ b/sys/boot/i386/libi386/biosdisk.c
@@ -214,10 +214,12 @@ bd_init(void)
     /* sequence 0, 0x80 */
     for (base = 0; base <= 0x80; base += 0x80) {
 	for (unit = base; (nbdinfo < MAXBDDEV); unit++) {
+#ifndef VIRTUALBOX
 	    /* check the BIOS equipment list for number of fixed disks */
 	    if((base == 0x80) &&
 	       (nfd >= *(unsigned char *)PTOV(BIOS_NUMDRIVES)))
-	        break;
+		break;
+#endif
 
 	    bdinfo[nbdinfo].bd_unit = unit;
 	    bdinfo[nbdinfo].bd_flags = (unit < 0x80) ? BD_FLOPPY : 0;
diff --git a/sys/boot/i386/zfsboot/zfsboot.c b/sys/boot/i386/zfsboot/zfsboot.c
index b6e5f0cfc7c4..c6ef699a4809 100644
--- a/sys/boot/i386/zfsboot/zfsboot.c
+++ b/sys/boot/i386/zfsboot/zfsboot.c
@@ -94,7 +94,7 @@ __FBSDID("$FreeBSD$");
 #define V86_CY(x)	((x) & 1)
 #define V86_ZR(x)	((x) & 0x40)
 
-#define BIOS_NUMDRIVES		0x475
+#define BIOS_NUMDRIVES	0x475
 #define DRV_HARD	0x80
 #define DRV_MASK	0x7f
 
@@ -667,7 +667,12 @@ main(void)
      * will find any other available pools and it may fill in missing
      * vdevs for the boot pool.
      */
-    for (i = 0; i < *(unsigned char *)PTOV(BIOS_NUMDRIVES); i++) {
+#ifndef VIRTUALBOX
+    for (i = 0; i < *(unsigned char *)PTOV(BIOS_NUMDRIVES); i++)
+#else
+    for (i = 0; i < MAXBDDEV; i++)
+#endif
+    {
 	if ((i | DRV_HARD) == *(uint8_t *)PTOV(ARGS))
 	    continue;