- Split code shared by almost any boot loader into separate files and

  clean up most layering violations:

	sys/boot/i386/common/rbx.h:

		RBX_* defines
		OPT_SET()
		OPT_CHECK()

	sys/boot/common/util.[ch]:

		memcpy()
		memset()
		memcmp()
		bcpy()
		bzero()
		bcmp()
		strcmp()
		strncmp() [new]
		strcpy()
		strcat()
		strchr()
		strlen()
		printf()

	sys/boot/i386/common/cons.[ch]:

		ioctrl
		putc()
		xputc()
		putchar()
		getc()
		xgetc()
		keyhit() [now takes number of seconds as an argument]
		getstr()

	sys/boot/i386/common/drv.[ch]:

		struct dsk
		drvread()
		drvwrite() [new]
		drvsize() [new]

	sys/boot/common/crc32.[ch] [new]

	sys/boot/common/gpt.[ch] [new]

- Teach gptboot and gptzfsboot about new files. I haven't touched the
  rest, but there is still a lot of code duplication to be removed.

- Implement full GPT support. Currently we just read primary header and
  partition table and don't care about checksums, etc. After this change we
  verify checksums of primary header and primary partition table and if
  there is a problem we fall back to backup header and backup partition
  table.

- Clean up most messages to use prefix of boot program, so in case of an
  error we know where the error comes from, eg.:

	gptboot: unable to read primary GPT header

- If we can't boot, print boot prompt only once and not every five
  seconds.

- Honour newly added GPT attributes:

	bootme - this is bootable partition
	bootonce - try to boot from this partition only once
	bootfailed - we failed to boot from this partition

- Change boot order of gptboot to the following:

	1. Try to boot from all the partitions that have both 'bootme'
	   and 'bootonce' attributes one by one.
	2. Try to boot from all the partitions that have only 'bootme'
	   attribute one by one.
	3. If there are no partitions with 'bootme' attribute, boot from
	   the first UFS partition.

- The 'bootonce' functionality is implemented in the following way:

	1. Walk through all the partitions and when 'bootonce'
	   attribute is found without 'bootme' attribute, remove
	   'bootonce' attribute and set 'bootfailed' attribute.
	   'bootonce' attribute alone means that we tried to boot from
	   this partition, but boot failed after leaving gptboot and
	   machine was restarted.
	2. Find partition with both 'bootme' and 'bootonce' attributes.
	3. Remove 'bootme' attribute.
	4. Try to execute /boot/loader or /boot/kernel/kernel from that
	   partition. If succeeded we stop here.
	5. If execution failed, remove 'bootonce' and set 'bootfailed'.
	6. Go to 2.

   If whole boot succeeded there is new /etc/rc.d/gptboot script coming
   that will log all partitions that we failed to boot from (the ones with
   'bootfailed' attribute) and will remove this attribute. It will also
   find partition with 'bootonce' attribute - this is the partition we
   booted from successfully. The script will log success and remove the
   attribute.

   All the GPT updates we do here goes to both primary and backup GPT if
   they are valid. We don't touch headers or partition tables when
   checksum doesn't match.

Reviewed by:	arch (Message-ID: <20100917234542.GE1902@garage.freebsd.pl>)
Obtained from:	Wheel Systems Sp. z o.o. http://www.wheelsystems.com
MFC after:	2 weeks

18 files changed, 1383 insertions, 864 deletions

diff --git a/sys/boot/common/crc32.c b/sys/boot/common/crc32.c
new file mode 100644
index 0000000..0325179
--- /dev/null
+++ b/sys/boot/common/crc32.c
@@ -0,0 +1,108 @@
+/*-
+ *  COPYRIGHT (C) 1986 Gary S. Brown.  You may use this program, or
+ *  code or tables extracted from it, as desired without restriction.
+ */
+
+/*
+ *  First, the polynomial itself and its table of feedback terms.  The
+ *  polynomial is
+ *  X^32+X^26+X^23+X^22+X^16+X^12+X^11+X^10+X^8+X^7+X^5+X^4+X^2+X^1+X^0
+ *
+ *  Note that we take it "backwards" and put the highest-order term in
+ *  the lowest-order bit.  The X^32 term is "implied"; the LSB is the
+ *  X^31 term, etc.  The X^0 term (usually shown as "+1") results in
+ *  the MSB being 1
+ *
+ *  Note that the usual hardware shift register implementation, which
+ *  is what we're using (we're merely optimizing it by doing eight-bit
+ *  chunks at a time) shifts bits into the lowest-order term.  In our
+ *  implementation, that means shifting towards the right.  Why do we
+ *  do it this way?  Because the calculated CRC must be transmitted in
+ *  order from highest-order term to lowest-order term.  UARTs transmit
+ *  characters in order from LSB to MSB.  By storing the CRC this way
+ *  we hand it to the UART in the order low-byte to high-byte; the UART
+ *  sends each low-bit to hight-bit; and the result is transmission bit
+ *  by bit from highest- to lowest-order term without requiring any bit
+ *  shuffling on our part.  Reception works similarly
+ *
+ *  The feedback terms table consists of 256, 32-bit entries.  Notes
+ *
+ *      The table can be generated at runtime if desired; code to do so
+ *      is shown later.  It might not be obvious, but the feedback
+ *      terms simply represent the results of eight shift/xor opera
+ *      tions for all combinations of data and CRC register values
+ *
+ *      The values must be right-shifted by eight bits by the "updcrc
+ *      logic; the shift must be unsigned (bring in zeroes).  On some
+ *      hardware you could probably optimize the shift in assembler by
+ *      using byte-swap instructions
+ *      polynomial $edb88320
+ *
+ *
+ * CRC32 code derived from work by Gary S. Brown.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+
+#include "crc32.h"
+
+static uint32_t crc32_tab[] = {
+	0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
+	0xe963a535, 0x9e6495a3,	0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
+	0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
+	0xf3b97148, 0x84be41de,	0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
+	0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,	0x14015c4f, 0x63066cd9,
+	0xfa0f3d63, 0x8d080df5,	0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
+	0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,	0x35b5a8fa, 0x42b2986c,
+	0xdbbbc9d6, 0xacbcf940,	0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
+	0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
+	0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
+	0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,	0x76dc4190, 0x01db7106,
+	0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
+	0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
+	0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
+	0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
+	0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
+	0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
+	0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
+	0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
+	0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
+	0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
+	0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
+	0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
+	0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
+	0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
+	0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
+	0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
+	0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
+	0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
+	0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
+	0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
+	0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
+	0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
+	0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
+	0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
+	0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
+	0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
+	0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
+	0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
+	0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
+	0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
+	0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
+	0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
+};
+
+uint32_t
+crc32(const void *buf, size_t size)
+{
+	const uint8_t *p = buf;
+	uint32_t crc;
+
+	crc = ~0U;
+	while (size--)
+		crc = crc32_tab[(crc ^ *p++) & 0xFF] ^ (crc >> 8);
+	return (crc ^ ~0U);
+}
diff --git a/sys/boot/common/crc32.h b/sys/boot/common/crc32.h
new file mode 100644
index 0000000..adfd628
--- /dev/null
+++ b/sys/boot/common/crc32.h
@@ -0,0 +1,13 @@
+/*-
+ *  COPYRIGHT (C) 1986 Gary S. Brown.  You may use this program, or
+ *  code or tables extracted from it, as desired without restriction.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _CRC32_H_
+#define	_CRC32_H_
+
+uint32_t crc32(const void *buf, size_t size);
+
+#endif	/* !_CRC32_H_ */
diff --git a/sys/boot/common/gpt.c b/sys/boot/common/gpt.c
new file mode 100644
index 0000000..62e86dd
--- /dev/null
+++ b/sys/boot/common/gpt.c
@@ -0,0 +1,381 @@
+/*-
+ * Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``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 AUTHORS OR CONTRIBUTORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/gpt.h>
+
+#ifndef LITTLE_ENDIAN
+#error gpt.c works only for little endian architectures
+#endif
+
+#include "crc32.h"
+#include "drv.h"
+#include "util.h"
+#include "gpt.h"
+
+#define	MAXTBLENTS	128
+
+static struct gpt_hdr hdr_primary, hdr_backup, *gpthdr;
+static uint64_t hdr_primary_lba, hdr_backup_lba;
+static struct gpt_ent table_primary[MAXTBLENTS], table_backup[MAXTBLENTS];
+static struct gpt_ent *gpttable;
+static int curent, bootonce;
+
+/*
+ * Buffer below 64kB passed on gptread(), which can hold at least
+ * one sector od data (512 bytes).
+ */
+static char *secbuf;
+
+static void
+gptupdate(const char *which, struct dsk *dskp, struct gpt_hdr *hdr,
+    struct gpt_ent *table)
+{
+	int entries_per_sec, firstent;
+	daddr_t slba;
+
+	/*
+	 * We need to update the following for both primary and backup GPT:
+	 * 1. Sector on disk that contains curent partition.
+	 * 2. Partition table checksum.
+	 * 3. Header checksum.
+	 * 4. Header on disk.
+	 */
+
+	entries_per_sec = DEV_BSIZE / hdr->hdr_entsz;
+	slba = curent / entries_per_sec;
+	firstent = slba * entries_per_sec;
+	bcpy(&table[firstent], secbuf, DEV_BSIZE);
+	slba += hdr->hdr_lba_table;
+	if (drvwrite(dskp, secbuf, slba, 1)) {
+		printf("%s: unable to update %s GPT partition table\n",
+		    BOOTPROG, which);
+		return;
+	}
+	hdr->hdr_crc_table = crc32(table, hdr->hdr_entries * hdr->hdr_entsz);
+	hdr->hdr_crc_self = 0;
+	hdr->hdr_crc_self = crc32(hdr, hdr->hdr_size);
+	bzero(secbuf, DEV_BSIZE);
+	bcpy(hdr, secbuf, hdr->hdr_size);
+	if (drvwrite(dskp, secbuf, hdr->hdr_lba_self, 1)) {
+		printf("%s: unable to update %s GPT header\n", BOOTPROG, which);
+		return;
+	}
+}
+
+int
+gptfind(const uuid_t *uuid, struct dsk *dskp, int part)
+{
+	struct gpt_ent *ent;
+	int firsttry;
+
+	if (part >= 0) {
+		if (part == 0 || part > gpthdr->hdr_entries) {
+			printf("%s: invalid partition index\n", BOOTPROG);
+			return (-1);
+		}
+		ent = &gpttable[part - 1];
+		if (bcmp(&ent->ent_type, uuid, sizeof(uuid_t)) != 0) {
+			printf("%s: specified partition is not UFS\n",
+			    BOOTPROG);
+			return (-1);
+		}
+		curent = part - 1;
+		goto found;
+	}
+
+	firsttry = (curent == -1);
+	curent++;
+	if (curent >= gpthdr->hdr_entries) {
+		curent = gpthdr->hdr_entries;
+		return (-1);
+	}
+	if (bootonce) {
+		/*
+		 * First look for partition with both GPT_ENT_ATTR_BOOTME and
+		 * GPT_ENT_ATTR_BOOTONCE flags.
+		 */
+		for (; curent < gpthdr->hdr_entries; curent++) {
+			ent = &gpttable[curent];
+			if (bcmp(&ent->ent_type, uuid, sizeof(uuid_t)) != 0)
+				continue;
+			if (!(ent->ent_attr & GPT_ENT_ATTR_BOOTME))
+				continue;
+			if (!(ent->ent_attr & GPT_ENT_ATTR_BOOTONCE))
+				continue;
+			/* Ok, found one. */
+			goto found;
+		}
+		bootonce = 0;
+		curent = 0;
+	}
+	for (; curent < gpthdr->hdr_entries; curent++) {
+		ent = &gpttable[curent];
+		if (bcmp(&ent->ent_type, uuid, sizeof(uuid_t)) != 0)
+			continue;
+		if (!(ent->ent_attr & GPT_ENT_ATTR_BOOTME))
+			continue;
+		if (ent->ent_attr & GPT_ENT_ATTR_BOOTONCE)
+			continue;
+		/* Ok, found one. */
+		goto found;
+	}
+	if (firsttry) {
+		/*
+		 * No partition with BOOTME flag was found, try to boot from
+		 * first UFS partition.
+		 */
+		for (curent = 0; curent < gpthdr->hdr_entries; curent++) {
+			ent = &gpttable[curent];
+			if (bcmp(&ent->ent_type, uuid, sizeof(uuid_t)) != 0)
+				continue;
+			/* Ok, found one. */
+			goto found;
+		}
+	}
+	return (-1);
+found:
+	dskp->part = curent + 1;
+	ent = &gpttable[curent];
+	dskp->start = ent->ent_lba_start;
+	if (ent->ent_attr & GPT_ENT_ATTR_BOOTONCE) {
+		/*
+		 * Clear BOOTME, but leave BOOTONCE set before trying to
+		 * boot from this partition.
+		 */
+		if (hdr_primary_lba > 0) {
+			table_primary[curent].ent_attr &= ~GPT_ENT_ATTR_BOOTME;
+			gptupdate("primary", dskp, &hdr_primary, table_primary);
+		}
+		if (hdr_backup_lba > 0) {
+			table_backup[curent].ent_attr &= ~GPT_ENT_ATTR_BOOTME;
+			gptupdate("backup", dskp, &hdr_backup, table_backup);
+		}
+	}
+	return (0);
+}
+
+static int
+gptread_hdr(const char *which, struct dsk *dskp, struct gpt_hdr *hdr,
+    uint64_t hdrlba)
+{
+	uint32_t crc;
+
+	if (drvread(dskp, secbuf, hdrlba, 1)) {
+		printf("%s: unable to read %s GPT header\n", BOOTPROG, which);
+		return (-1);
+	}
+	bcpy(secbuf, hdr, sizeof(*hdr));
+	if (bcmp(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig)) != 0 ||
+	    hdr->hdr_lba_self != hdrlba || hdr->hdr_revision < 0x00010000 ||
+	    hdr->hdr_entsz < sizeof(struct gpt_ent) ||
+	    hdr->hdr_entries > MAXTBLENTS || DEV_BSIZE % hdr->hdr_entsz != 0) {
+		printf("%s: invalid %s GPT header\n", BOOTPROG, which);
+		return (-1);
+	}
+	crc = hdr->hdr_crc_self;
+	hdr->hdr_crc_self = 0;
+	if (crc32(hdr, hdr->hdr_size) != crc) {
+		printf("%s: %s GPT header checksum mismatch\n", BOOTPROG,
+		    which);
+		return (-1);
+	}
+	hdr->hdr_crc_self = crc;
+	return (0);
+}
+
+void
+gptbootfailed(struct dsk *dskp)
+{
+
+	if (!(gpttable[curent].ent_attr & GPT_ENT_ATTR_BOOTONCE))
+		return;
+
+	if (hdr_primary_lba > 0) {
+		table_primary[curent].ent_attr &= ~GPT_ENT_ATTR_BOOTONCE;
+		table_primary[curent].ent_attr |= GPT_ENT_ATTR_BOOTFAILED;
+		gptupdate("primary", dskp, &hdr_primary, table_primary);
+	}
+	if (hdr_backup_lba > 0) {
+		table_backup[curent].ent_attr &= ~GPT_ENT_ATTR_BOOTONCE;
+		table_backup[curent].ent_attr |= GPT_ENT_ATTR_BOOTFAILED;
+		gptupdate("backup", dskp, &hdr_backup, table_backup);
+	}
+}
+
+static void
+gptbootconv(const char *which, struct dsk *dskp, struct gpt_hdr *hdr,
+    struct gpt_ent *table)
+{
+	struct gpt_ent *ent;
+	daddr_t slba;
+	int table_updated, sector_updated;
+	int entries_per_sec, nent, part;
+
+	table_updated = 0;
+	entries_per_sec = DEV_BSIZE / hdr->hdr_entsz;
+	for (nent = 0, slba = hdr->hdr_lba_table;
+	     slba < hdr->hdr_lba_table + hdr->hdr_entries / entries_per_sec;
+	     slba++, nent += entries_per_sec) {
+		sector_updated = 0;
+		for (part = 0; part < entries_per_sec; part++) {
+			ent = &table[nent + part];
+			if ((ent->ent_attr & (GPT_ENT_ATTR_BOOTME |
+			    GPT_ENT_ATTR_BOOTONCE |
+			    GPT_ENT_ATTR_BOOTFAILED)) !=
+			    GPT_ENT_ATTR_BOOTONCE) {
+				continue;
+			}
+			ent->ent_attr &= ~GPT_ENT_ATTR_BOOTONCE;
+			ent->ent_attr |= GPT_ENT_ATTR_BOOTFAILED;
+			table_updated = 1;
+			sector_updated = 1;
+		}
+		if (!sector_updated)
+			continue;
+		bcpy(&table[nent], secbuf, DEV_BSIZE);
+		if (drvwrite(dskp, secbuf, slba, 1)) {
+			printf("%s: unable to update %s GPT partition table\n",
+			    BOOTPROG, which);
+		}
+	}
+	if (!table_updated)
+		return;
+	hdr->hdr_crc_table = crc32(table, hdr->hdr_entries * hdr->hdr_entsz);
+	hdr->hdr_crc_self = 0;
+	hdr->hdr_crc_self = crc32(hdr, hdr->hdr_size);
+	bzero(secbuf, DEV_BSIZE);
+	bcpy(hdr, secbuf, hdr->hdr_size);
+	if (drvwrite(dskp, secbuf, hdr->hdr_lba_self, 1))
+		printf("%s: unable to update %s GPT header\n", BOOTPROG, which);
+}
+
+static int
+gptread_table(const char *which, const uuid_t *uuid, struct dsk *dskp,
+    struct gpt_hdr *hdr, struct gpt_ent *table)
+{
+	struct gpt_ent *ent;
+	int entries_per_sec;
+	int part, nent;
+	daddr_t slba;
+
+	if (hdr->hdr_entries == 0)
+		return (0);
+
+	entries_per_sec = DEV_BSIZE / hdr->hdr_entsz;
+	slba = hdr->hdr_lba_table;
+	nent = 0;
+	for (;;) {
+		if (drvread(dskp, secbuf, slba, 1)) {
+			printf("%s: unable to read %s GPT partition table\n",
+			    BOOTPROG, which);
+			return (-1);
+		}
+		ent = (struct gpt_ent *)secbuf;
+		for (part = 0; part < entries_per_sec; part++, ent++) {
+			bcpy(ent, &table[nent], sizeof(table[nent]));
+			if (++nent >= hdr->hdr_entries)
+				break;
+		}
+		if (nent >= hdr->hdr_entries)
+			break;
+		slba++;
+	}
+	if (crc32(table, nent * hdr->hdr_entsz) != hdr->hdr_crc_table) {
+		printf("%s: %s GPT table checksum mismatch\n", BOOTPROG, which);
+		return (-1);
+	}
+	return (0);
+}
+
+int
+gptread(const uuid_t *uuid, struct dsk *dskp, char *buf)
+{
+	uint64_t altlba;
+
+	/*
+	 * Read and verify both GPT headers: primary and backup.
+	 */
+
+	secbuf = buf;
+	hdr_primary_lba = hdr_backup_lba = 0;
+	curent = -1;
+	bootonce = 1;
+	dskp->start = 0;
+
+	if (gptread_hdr("primary", dskp, &hdr_primary, 1) == 0 &&
+	    gptread_table("primary", uuid, dskp, &hdr_primary,
+	    table_primary) == 0) {
+		hdr_primary_lba = hdr_primary.hdr_lba_self;
+		gpthdr = &hdr_primary;
+		gpttable = table_primary;
+	}
+
+	altlba = drvsize(dskp);
+	if (altlba > 0)
+		altlba--;
+	else if (hdr_primary_lba > 0) {
+		/*
+		 * If we cannot obtain disk size, but primary header
+		 * is valid, we can get backup header location from
+		 * there.
+		 */
+		altlba = hdr_primary.hdr_lba_alt;
+	}
+	if (altlba == 0)
+		printf("%s: unable to locate backup GPT header\n", BOOTPROG);
+	else if (gptread_hdr("backup", dskp, &hdr_backup, altlba) == 0 &&
+	    gptread_table("backup", uuid, dskp, &hdr_backup,
+	    table_backup) == 0) {
+		hdr_backup_lba = hdr_backup.hdr_lba_self;
+		if (hdr_primary_lba == 0) {
+			gpthdr = &hdr_backup;
+			gpttable = table_backup;
+			printf("%s: using backup GPT\n", BOOTPROG);
+		}
+	}
+
+	/*
+	 * Convert all BOOTONCE without BOOTME flags into BOOTFAILED.
+	 * BOOTONCE without BOOTME means that we tried to boot from it,
+	 * but failed after leaving gptboot and machine was rebooted.
+	 * We don't want to leave partitions marked as BOOTONCE only,
+	 * because when we boot successfully start-up scripts should
+	 * find at most one partition with only BOOTONCE flag and this
+	 * will mean that we booted from that partition.
+	 */
+	if (hdr_primary_lba != 0)
+		gptbootconv("primary", dskp, &hdr_primary, table_primary);
+	if (hdr_backup_lba != 0)
+		gptbootconv("backup", dskp, &hdr_backup, table_backup);
+
+	if (hdr_primary_lba == 0 && hdr_backup_lba == 0)
+		return (-1);
+	return (0);
+}
diff --git a/sys/boot/common/gpt.h b/sys/boot/common/gpt.h
new file mode 100644
index 0000000..c42b40d
--- /dev/null
+++ b/sys/boot/common/gpt.h
@@ -0,0 +1,39 @@
+/*-
+ * Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``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 AUTHORS OR CONTRIBUTORS 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _GPT_H_
+#define	_GPT_H_
+
+#include <uuid.h>
+#include <drv.h>
+
+int gptread(const uuid_t *uuid, struct dsk *dskp, char *buf);
+int gptfind(const uuid_t *uuid, struct dsk *dskp, int part);
+void gptbootfailed(struct dsk *dskp);
+
+#endif	/* !_GPT_H_ */
diff --git a/sys/boot/common/util.c b/sys/boot/common/util.c
new file mode 100644
index 0000000..012106a
--- /dev/null
+++ b/sys/boot/common/util.c
@@ -0,0 +1,176 @@
+/*-
+ * Copyright (c) 1998 Robert Nordier
+ * Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are freely
+ * permitted provided that the above copyright notice and this
+ * paragraph and the following disclaimer are duplicated in all
+ * such forms.
+ *
+ * This software is provided "AS IS" and without any express or
+ * implied warranties, including, without limitation, the implied
+ * warranties of merchantability and fitness for a particular
+ * purpose.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+
+#include <stdarg.h>
+
+#include "cons.h"
+#include "util.h"
+
+void
+memcpy(void *dst, const void *src, int len)
+{
+	const char *s = src;
+	char *d = dst;
+
+	while (len--)
+		*d++ = *s++;
+}
+
+void
+memset(void *b, int c, size_t len)
+{
+	char *bp = b;
+
+	while (len--)
+		*bp++ = (unsigned char)c;
+}
+
+int
+memcmp(const void *b1, const void *b2, size_t len)
+{
+	const unsigned char *p1, *p2;
+
+	for (p1 = b1, p2 = b2; len > 0; len--, p1++, p2++) {
+		if (*p1 != *p2)
+			return ((*p1) - (*p2));
+	}
+	return (0);
+}
+
+int
+strcmp(const char *s1, const char *s2)
+{
+
+	for (; *s1 == *s2 && *s1 != '\0'; s1++, s2++)
+		;
+	return ((unsigned char)*s1 - (unsigned char)*s2);
+}
+
+int
+strncmp(const char *s1, const char *s2, size_t len)
+{
+
+	for (; *s1 == *s2 && *s1 != '\0' && len > 0; len--, s1++, s2++)
+		;
+	return ((unsigned char)*s1 - (unsigned char)*s2);
+}
+
+void
+strcpy(char *dst, const char *src)
+{
+
+	while (*src != '\0')
+		*dst++ = *src++;
+	*dst = '\0';
+}
+
+void
+strcat(char *dst, const char *src)
+{
+
+	while (*dst != '\0')
+		dst++;
+	while (*src != '\0')
+		*dst++ = *src++;
+	*dst = '\0';
+}
+
+char *
+strchr(const char *s, char ch)
+{
+
+	for (; *s != '\0'; s++) {
+		if (*s == ch)
+			return ((char *)(uintptr_t)(const void *)s);
+	}
+	return (NULL);
+}
+
+size_t
+strlen(const char *s)
+{
+	size_t len = 0;
+
+	while (*s++ != '\0')
+		len++;
+	return (len);
+}
+
+void
+printf(const char *fmt, ...)
+{
+	va_list ap;
+	const char *hex = "0123456789abcdef";
+	char buf[10], *s;
+	unsigned long long u;
+	int c, l;
+
+	va_start(ap, fmt);
+	while ((c = *fmt++) != '\0') {
+		if (c != '%') {
+			putchar(c);
+			continue;
+		}
+		l = 0;
+nextfmt:
+		c = *fmt++;
+		switch (c) {
+		case 'l':
+			l++;
+			goto nextfmt;
+		case 'c':
+			putchar(va_arg(ap, int));
+			break;
+		case 's':
+			for (s = va_arg(ap, char *); *s != '\0'; s++)
+				putchar(*s);
+			break;
+		case 'd':	/* A lie, always prints unsigned */
+		case 'u':
+		case 'x':
+			switch (l) {
+			case 2:
+				u = va_arg(ap, unsigned long long);
+				break;
+			case 1:
+				u = va_arg(ap, unsigned long);
+				break;
+			default:
+				u = va_arg(ap, unsigned int);
+				break;
+			}
+			s = buf;
+			if (c == 'd' || c == 'u') {
+				do
+					*s++ = '0' + (u % 10U);
+				while (u /= 10);
+			} else {
+				do
+					*s++ = hex[u & 0xfu];
+				while (u >>= 4);
+			}
+			while (--s >= buf)
+				putchar(*s);
+			break;
+		}
+	}
+	va_end(ap);
+}
diff --git a/sys/boot/common/util.h b/sys/boot/common/util.h
new file mode 100644
index 0000000..600c4e0
--- /dev/null
+++ b/sys/boot/common/util.h
@@ -0,0 +1,53 @@
+/*-
+ * Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``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 AUTHORS OR CONTRIBUTORS 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _UTIL_H_
+#define	_UTIL_H_
+
+#include <sys/types.h>
+
+#include <stdarg.h>
+
+void memcpy(void *dst, const void *src, int len);
+void memset(void *b, int c, size_t len);
+int memcmp(const void *b1, const void *b2, size_t len);
+
+#define	bcpy(src, dst, len)	memcpy((dst), (src), (len))
+#define	bzero(buf, size)	memset((buf), 0, (size))
+#define	bcmp(b1, b2, len)	(memcmp((b1), (b2), (len)) != 0)
+
+int strcmp(const char *s1, const char *s2);
+int strncmp(const char *s1, const char *s2, size_t len);
+void strcpy(char *dst, const char *src);
+void strcat(char *dst, const char *src);
+char *strchr(const char *s, char ch);
+size_t strlen(const char *s);
+
+void printf(const char *fmt, ...);
+
+#endif	/* !_UTIL_H_ */
diff --git a/sys/boot/i386/common/cons.c b/sys/boot/i386/common/cons.c
new file mode 100644
index 0000000..56febf2
--- /dev/null
+++ b/sys/boot/i386/common/cons.c
@@ -0,0 +1,152 @@
+/*-
+ * Copyright (c) 1998 Robert Nordier
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are freely
+ * permitted provided that the above copyright notice and this
+ * paragraph and the following disclaimer are duplicated in all
+ * such forms.
+ *
+ * This software is provided "AS IS" and without any express or
+ * implied warranties, including, without limitation, the implied
+ * warranties of merchantability and fitness for a particular
+ * purpose.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+
+#include <machine/psl.h>
+
+#include <btxv86.h>
+
+#include "lib.h"
+#include "rbx.h"
+#include "util.h"
+#include "cons.h"
+
+#define	V86_ZR(x)	((x) & PSL_Z)
+
+#define SECOND		18	/* Circa that many ticks in a second. */
+
+uint8_t ioctrl = IO_KEYBOARD;
+
+void
+putc(int c)
+{
+
+	v86.addr = 0x10;
+	v86.eax = 0xe00 | (c & 0xff);
+	v86.ebx = 0x7;
+	v86int();
+}
+
+void
+xputc(int c)
+{
+
+	if (ioctrl & IO_KEYBOARD)
+		putc(c);
+	if (ioctrl & IO_SERIAL)
+		sio_putc(c);
+}
+
+void
+putchar(int c)
+{
+
+	if (c == '\n')
+		xputc('\r');
+	xputc(c);
+}
+
+int
+getc(int fn)
+{
+
+	/*
+	 * The extra comparison against zero is an attempt to work around
+	 * what appears to be a bug in QEMU and Bochs. Both emulators
+	 * sometimes report a key-press with scancode one and ascii zero
+	 * when no such key is pressed in reality. As far as I can tell,
+	 * this only happens shortly after a reboot.
+	 */
+	v86.ctl = V86_FLAGS;
+	v86.addr = 0x16;
+	v86.eax = fn << 8;
+	v86int();
+	return fn == 0 ? v86.eax & 0xff : (!V86_ZR(v86.efl) && (v86.eax & 0xff));
+}
+
+int
+xgetc(int fn)
+{
+
+	if (OPT_CHECK(RBX_NOINTR))
+		return (0);
+	for (;;) {
+		if (ioctrl & IO_KEYBOARD && getc(1))
+			return (fn ? 1 : getc(0));
+		if (ioctrl & IO_SERIAL && sio_ischar())
+			return (fn ? 1 : sio_getc());
+		if (fn)
+			return (0);
+	}
+	/* NOTREACHED */
+}
+
+int
+keyhit(unsigned int secs)
+{
+	uint32_t t0, t1;
+
+	if (OPT_CHECK(RBX_NOINTR))
+		return (0);
+	secs *= SECOND;
+	t0 = 0;
+	for (;;) {
+		if (xgetc(1))
+			return (1);
+		if (secs > 0) {
+			t1 = *(uint32_t *)PTOV(0x46c);
+			if (!t0)
+				t0 = t1;
+			if (t1 < t0 || t1 >= t0 + secs)
+				return (0);
+		}
+	}
+	/* NOTREACHED */
+}
+
+void
+getstr(char *cmdstr, size_t cmdstrsize)
+{
+	char *s;
+	int c;
+
+	s = cmdstr;
+	for (;;) {
+		switch (c = xgetc(0)) {
+		case 0:
+			break;
+		case '\177':
+		case '\b':
+			if (s > cmdstr) {
+				s--;
+				printf("\b \b");
+			}
+			break;
+		case '\n':
+		case '\r':
+			*s = 0;
+			return;
+		default:
+			if (s - cmdstr < cmdstrsize - 1)
+				*s++ = c;
+			putchar(c);
+			break;
+		}
+	}
+}
diff --git a/sys/boot/i386/common/cons.h b/sys/boot/i386/common/cons.h
new file mode 100644
index 0000000..fe00a13
--- /dev/null
+++ b/sys/boot/i386/common/cons.h
@@ -0,0 +1,34 @@
+/*-
+ * Copyright (c) 1998 Robert Nordier
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are freely
+ * permitted provided that the above copyright notice and this
+ * paragraph and the following disclaimer are duplicated in all
+ * such forms.
+ *
+ * This software is provided "AS IS" and without any express or
+ * implied warranties, including, without limitation, the implied
+ * warranties of merchantability and fitness for a particular
+ * purpose.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _CONS_H_
+#define	_CONS_H_
+
+#define IO_KEYBOARD	1
+#define IO_SERIAL	2
+
+extern uint8_t ioctrl;
+
+void putc(int c);
+void xputc(int c);
+void putchar(int c);
+int getc(int fn);
+int xgetc(int fn);
+int keyhit(unsigned int secs);
+void getstr(char *cmdstr, size_t cmdstrsize);
+
+#endif	/* !_CONS_H_ */
diff --git a/sys/boot/i386/common/drv.c b/sys/boot/i386/common/drv.c
new file mode 100644
index 0000000..d249bc1
--- /dev/null
+++ b/sys/boot/i386/common/drv.c
@@ -0,0 +1,131 @@
+/*-
+ * Copyright (c) 1998 Robert Nordier
+ * Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are freely
+ * permitted provided that the above copyright notice and this
+ * paragraph and the following disclaimer are duplicated in all
+ * such forms.
+ *
+ * This software is provided "AS IS" and without any express or
+ * implied warranties, including, without limitation, the implied
+ * warranties of merchantability and fitness for a particular
+ * purpose.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+
+#include <machine/psl.h>
+
+#include <btxv86.h>
+
+#include "rbx.h"
+#include "util.h"
+#include "drv.h"
+#ifndef GPT
+#include "xreadorg.h"
+#endif
+
+#define	V86_CY(x)	((x) & PSL_C)
+#define	V86_ZR(x)	((x) & PSL_Z)
+
+#ifdef GPT
+uint64_t
+drvsize(struct dsk *dskp)
+{
+	unsigned char params[0x42];
+	uint64_t sectors;
+
+	*(uint32_t *)params = sizeof(params);
+
+	v86.ctl = V86_FLAGS;
+	v86.addr = 0x13;
+	v86.eax = 0x4800;
+	v86.edx = dskp->drive;
+	v86.ds = VTOPSEG(params);
+	v86.esi = VTOPOFF(params);
+	v86int();
+	if (V86_CY(v86.efl)) {
+		printf("error %u\n", v86.eax >> 8 & 0xff);
+		return (0);
+	}
+	memcpy(&sectors, params + 0x10, sizeof(sectors));
+	return (sectors);
+}
+#endif	/* GPT */
+
+#ifdef GPT
+static struct {
+	uint16_t	len;
+	uint16_t	count;
+	uint16_t	off;
+	uint16_t	seg;
+	uint64_t	lba;
+} packet;
+#endif	/* GPT */
+
+int
+drvread(struct dsk *dskp, void *buf, daddr_t lba, unsigned nblk)
+{
+	static unsigned c = 0x2d5c7c2f;
+
+	if (!OPT_CHECK(RBX_QUIET))
+		printf("%c\b", c = c << 8 | c >> 24);
+#ifdef GPT
+	packet.len = 0x10;
+	packet.count = nblk;
+	packet.off = VTOPOFF(buf);
+	packet.seg = VTOPSEG(buf);
+	packet.lba = lba;
+	v86.ctl = V86_FLAGS;
+	v86.addr = 0x13;
+	v86.eax = 0x4200;
+	v86.edx = dskp->drive;
+	v86.ds = VTOPSEG(&packet);
+	v86.esi = VTOPOFF(&packet);
+#else	/* !GPT */
+	v86.ctl = V86_ADDR | V86_CALLF | V86_FLAGS;
+	v86.addr = XREADORG;		/* call to xread in boot1 */
+	v86.es = VTOPSEG(buf);
+	v86.eax = lba;
+	v86.ebx = VTOPOFF(buf);
+	v86.ecx = lba >> 32;
+	v86.edx = nblk << 8 | dskp->drive;
+#endif	/* !GPT */
+	v86int();
+	if (V86_CY(v86.efl)) {
+		printf("%s: error %u lba %u\n",
+		    BOOTPROG, v86.eax >> 8 & 0xff, lba);
+		return (-1);
+	}
+	return (0);
+}
+
+#ifdef GPT
+int
+drvwrite(struct dsk *dskp, void *buf, daddr_t lba, unsigned nblk)
+{
+
+	packet.len = 0x10;
+	packet.count = nblk;
+	packet.off = VTOPOFF(buf);
+	packet.seg = VTOPSEG(buf);
+	packet.lba = lba;
+	v86.ctl = V86_FLAGS;
+	v86.addr = 0x13;
+	v86.eax = 0x4300;
+	v86.edx = dskp->drive;
+	v86.ds = VTOPSEG(&packet);
+	v86.esi = VTOPOFF(&packet);
+	v86int();
+	if (V86_CY(v86.efl)) {
+		printf("error %u lba %u\n", v86.eax >> 8 & 0xff, lba);
+		return (-1);
+	}
+	return (0);
+}
+#endif	/* GPT */
diff --git a/sys/boot/i386/common/drv.h b/sys/boot/i386/common/drv.h
new file mode 100644
index 0000000..1ecfbc3
--- /dev/null
+++ b/sys/boot/i386/common/drv.h
@@ -0,0 +1,48 @@
+/*-
+ * Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``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 AUTHORS OR CONTRIBUTORS 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _DRV_H_
+#define _DRV_H_
+
+struct dsk {
+	unsigned int drive;
+	unsigned int type;
+	unsigned int unit;
+	unsigned int slice;
+	int part;
+	daddr_t start;
+	int init;
+};
+
+int drvread(struct dsk *dskp, void *buf, daddr_t lba, unsigned nblk);
+#ifdef GPT
+int drvwrite(struct dsk *dskp, void *buf, daddr_t lba, unsigned nblk);
+uint64_t drvsize(struct dsk *dskp);
+#endif	/* GPT */
+
+#endif	/* !_DRV_H_ */
diff --git a/sys/boot/i386/common/rbx.h b/sys/boot/i386/common/rbx.h
new file mode 100644
index 0000000..21371a5
--- /dev/null
+++ b/sys/boot/i386/common/rbx.h
@@ -0,0 +1,61 @@
+/*-
+ * Copyright (c) 1998 Robert Nordier
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are freely
+ * permitted provided that the above copyright notice and this
+ * paragraph and the following disclaimer are duplicated in all
+ * such forms.
+ *
+ * This software is provided "AS IS" and without any express or
+ * implied warranties, including, without limitation, the implied
+ * warranties of merchantability and fitness for a particular
+ * purpose.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _RBX_H_
+#define	_RBX_H_
+
+#define RBX_ASKNAME	0x0	/* -a */
+#define RBX_SINGLE	0x1	/* -s */
+/* 0x2 is reserved for log2(RB_NOSYNC). */
+/* 0x3 is reserved for log2(RB_HALT). */
+/* 0x4 is reserved for log2(RB_INITNAME). */
+#define RBX_DFLTROOT	0x5	/* -r */
+#define RBX_KDB 	0x6	/* -d */
+/* 0x7 is reserved for log2(RB_RDONLY). */
+/* 0x8 is reserved for log2(RB_DUMP). */
+/* 0x9 is reserved for log2(RB_MINIROOT). */
+#define RBX_CONFIG	0xa	/* -c */
+#define RBX_VERBOSE	0xb	/* -v */
+#define RBX_SERIAL	0xc	/* -h */
+#define RBX_CDROM	0xd	/* -C */
+/* 0xe is reserved for log2(RB_POWEROFF). */
+#define RBX_GDB 	0xf	/* -g */
+#define RBX_MUTE	0x10	/* -m */
+/* 0x11 is reserved for log2(RB_SELFTEST). */
+/* 0x12 is reserved for boot programs. */
+/* 0x13 is reserved for boot programs. */
+#define RBX_PAUSE	0x14	/* -p */
+#define RBX_QUIET	0x15	/* -q */
+#define RBX_NOINTR	0x1c	/* -n */
+/* 0x1d is reserved for log2(RB_MULTIPLE) and is just misnamed here. */
+#define RBX_DUAL	0x1d	/* -D */
+/* 0x1f is reserved for log2(RB_BOOTINFO). */
+
+/* pass: -a, -s, -r, -d, -c, -v, -h, -C, -g, -m, -p, -D */
+#define RBX_MASK	(OPT_SET(RBX_ASKNAME) | OPT_SET(RBX_SINGLE) | \
+			OPT_SET(RBX_DFLTROOT) | OPT_SET(RBX_KDB ) | \
+			OPT_SET(RBX_CONFIG) | OPT_SET(RBX_VERBOSE) | \
+			OPT_SET(RBX_SERIAL) | OPT_SET(RBX_CDROM) | \
+			OPT_SET(RBX_GDB ) | OPT_SET(RBX_MUTE) | \
+			OPT_SET(RBX_PAUSE) | OPT_SET(RBX_DUAL))
+
+#define OPT_SET(opt)	(1 << (opt))
+#define OPT_CHECK(opt)	((opts) & OPT_SET(opt))
+
+extern uint32_t opts;
+
+#endif	/* !_RBX_H_ */
diff --git a/sys/boot/i386/gptboot/Makefile b/sys/boot/i386/gptboot/Makefile
index f76fb4e..3b43537 100644
--- a/sys/boot/i386/gptboot/Makefile
+++ b/sys/boot/i386/gptboot/Makefile
@@ -1,6 +1,6 @@
 # $FreeBSD$
 
-.PATH:		${.CURDIR}/../boot2
+.PATH:		${.CURDIR}/../boot2 ${.CURDIR}/../common ${.CURDIR}/../../common
 
 FILES=		gptboot
 
@@ -19,18 +19,21 @@ GPTBOOT_UFS?=	UFS1_AND_UFS2
 #GPTBOOT_UFS?=	UFS2_ONLY
 #GPTBOOT_UFS?=	UFS1_ONLY
 
-CFLAGS=	-Os \
+CFLAGS=	-DBOOTPROG=\"gptboot\" \
+	-Os \
 	-fno-guess-branch-probability \
 	-fomit-frame-pointer \
 	-fno-unit-at-a-time \
 	-mno-align-long-strings \
 	-mrtd \
 	-mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3 \
+	-DGPT \
 	-D${GPTBOOT_UFS} \
 	-DSIOPRT=${BOOT_COMCONSOLE_PORT} \
 	-DSIOFMT=${B2SIOFMT} \
 	-DSIOSPD=${BOOT_COMCONSOLE_SPEED} \
 	-I${.CURDIR}/../../common \
+	-I${.CURDIR}/../common \
 	-I${.CURDIR}/../btx/lib -I. \
 	-I${.CURDIR}/../boot2 \
 	-Wall -Waggregate-return -Wbad-function-cast -Wcast-align \
@@ -57,13 +60,13 @@ gptldr.bin: gptldr.out
 gptldr.out: gptldr.o
 	${LD} ${LDFLAGS} -e start -Ttext ${ORG1} -o ${.TARGET} gptldr.o
 
-CLEANFILES+=	gptboot.bin gptboot.out gptboot.o sio.o
+CLEANFILES+=	gptboot.bin gptboot.out gptboot.o sio.o ufsread.o
 
 gptboot.bin: gptboot.out
 	objcopy -S -O binary gptboot.out ${.TARGET}
 
-gptboot.out: ${BTXCRT} gptboot.o sio.o
-	${LD} ${LDFLAGS} -Ttext ${ORG2} -o ${.TARGET} ${.ALLSRC}
+gptboot.out: ${BTXCRT} gptboot.o sio.o gpt.o crc32.o drv.o cons.o util.o
+	${LD} ${LDFLAGS} -Ttext ${ORG2} -o ${.TARGET} ${.ALLSRC} ${LIBSTAND}
 
 gptboot.o: ${.CURDIR}/../../common/ufsread.c
 
diff --git a/sys/boot/i386/gptboot/gptboot.c b/sys/boot/i386/gptboot/gptboot.c
index 6939556..5f0ab7c 100644
--- a/sys/boot/i386/gptboot/gptboot.c
+++ b/sys/boot/i386/gptboot/gptboot.c
@@ -32,46 +32,11 @@ __FBSDID("$FreeBSD$");
 #include <btxv86.h>
 
 #include "lib.h"
-
-#define IO_KEYBOARD	1
-#define IO_SERIAL	2
-
-#define SECOND		18	/* Circa that many ticks in a second. */
-
-#define RBX_ASKNAME	0x0	/* -a */
-#define RBX_SINGLE	0x1	/* -s */
-/* 0x2 is reserved for log2(RB_NOSYNC). */
-/* 0x3 is reserved for log2(RB_HALT). */
-/* 0x4 is reserved for log2(RB_INITNAME). */
-#define RBX_DFLTROOT	0x5	/* -r */
-#define RBX_KDB 	0x6	/* -d */
-/* 0x7 is reserved for log2(RB_RDONLY). */
-/* 0x8 is reserved for log2(RB_DUMP). */
-/* 0x9 is reserved for log2(RB_MINIROOT). */
-#define RBX_CONFIG	0xa	/* -c */
-#define RBX_VERBOSE	0xb	/* -v */
-#define RBX_SERIAL	0xc	/* -h */
-#define RBX_CDROM	0xd	/* -C */
-/* 0xe is reserved for log2(RB_POWEROFF). */
-#define RBX_GDB 	0xf	/* -g */
-#define RBX_MUTE	0x10	/* -m */
-/* 0x11 is reserved for log2(RB_SELFTEST). */
-/* 0x12 is reserved for boot programs. */
-/* 0x13 is reserved for boot programs. */
-#define RBX_PAUSE	0x14	/* -p */
-#define RBX_QUIET	0x15	/* -q */
-#define RBX_NOINTR	0x1c	/* -n */
-/* 0x1d is reserved for log2(RB_MULTIPLE) and is just misnamed here. */
-#define RBX_DUAL	0x1d	/* -D */
-/* 0x1f is reserved for log2(RB_BOOTINFO). */
-
-/* pass: -a, -s, -r, -d, -c, -v, -h, -C, -g, -m, -p, -D */
-#define RBX_MASK	(OPT_SET(RBX_ASKNAME) | OPT_SET(RBX_SINGLE) | \
-			OPT_SET(RBX_DFLTROOT) | OPT_SET(RBX_KDB ) | \
-			OPT_SET(RBX_CONFIG) | OPT_SET(RBX_VERBOSE) | \
-			OPT_SET(RBX_SERIAL) | OPT_SET(RBX_CDROM) | \
-			OPT_SET(RBX_GDB ) | OPT_SET(RBX_MUTE) | \
-			OPT_SET(RBX_PAUSE) | OPT_SET(RBX_DUAL))
+#include "rbx.h"
+#include "drv.h"
+#include "util.h"
+#include "cons.h"
+#include "gpt.h"
 
 #define PATH_CONFIG	"/boot.config"
 #define PATH_BOOT3	"/boot/loader"
@@ -82,8 +47,6 @@ __FBSDID("$FreeBSD$");
 #define NDEV		3
 #define MEM_BASE	0x12
 #define MEM_EXT 	0x15
-#define V86_CY(x)	((x) & PSL_C)
-#define V86_ZR(x)	((x) & PSL_Z)
 
 #define DRV_HARD	0x80
 #define DRV_MASK	0x7f
@@ -93,211 +56,178 @@ __FBSDID("$FreeBSD$");
 #define TYPE_MAXHARD	TYPE_DA
 #define TYPE_FD		2
 
-#define OPT_SET(opt)	(1 << (opt))
-#define OPT_CHECK(opt)	((opts) & OPT_SET(opt))
-
 extern uint32_t _end;
 
 static const uuid_t freebsd_ufs_uuid = GPT_ENT_TYPE_FREEBSD_UFS;
 static const char optstr[NOPT] = "DhaCcdgmnpqrsv"; /* Also 'P', 'S' */
 static const unsigned char flags[NOPT] = {
-    RBX_DUAL,
-    RBX_SERIAL,
-    RBX_ASKNAME,
-    RBX_CDROM,
-    RBX_CONFIG,
-    RBX_KDB,
-    RBX_GDB,
-    RBX_MUTE,
-    RBX_NOINTR,
-    RBX_PAUSE,
-    RBX_QUIET,
-    RBX_DFLTROOT,
-    RBX_SINGLE,
-    RBX_VERBOSE
+	RBX_DUAL,
+	RBX_SERIAL,
+	RBX_ASKNAME,
+	RBX_CDROM,
+	RBX_CONFIG,
+	RBX_KDB,
+	RBX_GDB,
+	RBX_MUTE,
+	RBX_NOINTR,
+	RBX_PAUSE,
+	RBX_QUIET,
+	RBX_DFLTROOT,
+	RBX_SINGLE,
+	RBX_VERBOSE
 };
+uint32_t opts;
 
 static const char *const dev_nm[NDEV] = {"ad", "da", "fd"};
 static const unsigned char dev_maj[NDEV] = {30, 4, 2};
 
-static struct dsk {
-    unsigned drive;
-    unsigned type;
-    unsigned unit;
-    int part;
-    daddr_t start;
-    int init;
-} dsk;
-static char cmd[512], cmddup[512];
+static struct dsk dsk;
 static char kname[1024];
-static uint32_t opts;
 static int comspeed = SIOSPD;
 static struct bootinfo bootinfo;
-static uint8_t ioctrl = IO_KEYBOARD;
 
 void exit(int);
-static int bcmp(const void *, const void *, size_t);
 static void load(void);
-static int parse(void);
+static int parse(char *, int *);
 static int xfsread(ino_t, void *, size_t);
 static int dskread(void *, daddr_t, unsigned);
-static void printf(const char *,...);
-static void putchar(int);
-static void memcpy(void *, const void *, int);
 static uint32_t memsize(void);
-static int drvread(void *, daddr_t, unsigned);
-static int keyhit(unsigned);
-static int xputc(int);
-static int xgetc(int);
-static int getc(int);
-
-static void
-memcpy(void *dst, const void *src, int len)
-{
-    const char *s = src;
-    char *d = dst;
-
-    while (len--)
-        *d++ = *s++;
-}
-
-static inline int
-strcmp(const char *s1, const char *s2)
-{
-    for (; *s1 == *s2 && *s1; s1++, s2++);
-    return (unsigned char)*s1 - (unsigned char)*s2;
-}
 
 #include "ufsread.c"
 
 static inline int
 xfsread(ino_t inode, void *buf, size_t nbyte)
 {
-    if ((size_t)fsread(inode, buf, nbyte) != nbyte) {
-	printf("Invalid %s\n", "format");
-	return -1;
-    }
-    return 0;
+
+	if ((size_t)fsread(inode, buf, nbyte) != nbyte) {
+		printf("Invalid %s\n", "format");
+		return (-1);
+	}
+	return (0);
 }
 
 static inline uint32_t
 memsize(void)
 {
-    v86.addr = MEM_EXT;
-    v86.eax = 0x8800;
-    v86int();
-    return v86.eax;
-}
 
-static inline void
-getstr(void)
-{
-    char *s;
-    int c;
-
-    s = cmd;
-    for (;;) {
-	switch (c = xgetc(0)) {
-	case 0:
-	    break;
-	case '\177':
-	case '\b':
-	    if (s > cmd) {
-		s--;
-		printf("\b \b");
-	    }
-	    break;
-	case '\n':
-	case '\r':
-	    *s = 0;
-	    return;
-	default:
-	    if (s - cmd < sizeof(cmd) - 1)
-		*s++ = c;
-	    putchar(c);
-	}
-    }
+	v86.addr = MEM_EXT;
+	v86.eax = 0x8800;
+	v86int();
+	return (v86.eax);
 }
 
-static inline void
-putc(int c)
+static int
+gptinit(void)
 {
-    v86.addr = 0x10;
-    v86.eax = 0xe00 | (c & 0xff);
-    v86.ebx = 0x7;
-    v86int();
+
+	if (gptread(&freebsd_ufs_uuid, &dsk, dmadat->secbuf) == -1) {
+		printf("%s: unable to load GPT\n", BOOTPROG);
+		return (-1);
+	}
+	if (gptfind(&freebsd_ufs_uuid, &dsk, dsk.part) == -1) {
+		printf("%s: no UFS partition was found\n", BOOTPROG);
+		return (-1);
+	}
+	dsk_meta = 0;
+	return (0);
 }
 
 int
 main(void)
 {
-    int autoboot;
-    ino_t ino;
+	char cmd[512], cmdtmp[512];
+	int autoboot, dskupdated;
+	ino_t ino;
+
+	dmadat = (void *)(roundup2(__base + (int32_t)&_end, 0x10000) - __base);
+	v86.ctl = V86_FLAGS;
+	v86.efl = PSL_RESERVED_DEFAULT | PSL_I;
+	dsk.drive = *(uint8_t *)PTOV(ARGS);
+	dsk.type = dsk.drive & DRV_HARD ? TYPE_AD : TYPE_FD;
+	dsk.unit = dsk.drive & DRV_MASK;
+	dsk.part = -1;
+	dsk.start = 0;
+	bootinfo.bi_version = BOOTINFO_VERSION;
+	bootinfo.bi_size = sizeof(bootinfo);
+	bootinfo.bi_basemem = 0;	/* XXX will be filled by loader or kernel */
+	bootinfo.bi_extmem = memsize();
+	bootinfo.bi_memsizes_valid++;
+
+	/* Process configuration file */
+
+	if (gptinit() != 0)
+		return (-1);
+
+	autoboot = 1;
+	*cmd = '\0';
+
+	for (;;) {
+		*kname = '\0';
+		ino = lookup(PATH_CONFIG);
+		if (ino > 0)
+			fsread(ino, cmd, sizeof(cmd));
+
+		if (*cmd != '\0') {
+			memcpy(cmdtmp, cmd, sizeof(cmdtmp));
+			if (parse(cmdtmp, &dskupdated))
+				break;
+			if (dskupdated && gptinit() != 0)
+				break;
+			if (!OPT_CHECK(RBX_QUIET))
+				printf("%s: %s", PATH_CONFIG, cmd);
+			*cmd = '\0';
+		}
 
-    dmadat = (void *)(roundup2(__base + (int32_t)&_end, 0x10000) - __base);
-    v86.ctl = V86_FLAGS;
-    v86.efl = PSL_RESERVED_DEFAULT | PSL_I;
-    dsk.drive = *(uint8_t *)PTOV(ARGS);
-    dsk.type = dsk.drive & DRV_HARD ? TYPE_AD : TYPE_FD;
-    dsk.unit = dsk.drive & DRV_MASK;
-    dsk.part = -1;
-    bootinfo.bi_version = BOOTINFO_VERSION;
-    bootinfo.bi_size = sizeof(bootinfo);
-    bootinfo.bi_basemem = 0;	/* XXX will be filled by loader or kernel */
-    bootinfo.bi_extmem = memsize();
-    bootinfo.bi_memsizes_valid++;
-
-    /* Process configuration file */
-
-    autoboot = 1;
-
-    if ((ino = lookup(PATH_CONFIG)))
-	fsread(ino, cmd, sizeof(cmd));
-
-    if (*cmd) {
-	memcpy(cmddup, cmd, sizeof(cmd));
-	if (parse())
-	    autoboot = 0;
-	if (!OPT_CHECK(RBX_QUIET))
-	    printf("%s: %s", PATH_CONFIG, cmddup);
-	/* Do not process this command twice */
-	*cmd = 0;
-    }
+		if (autoboot && keyhit(3)) {
+			if (*kname == '\0')
+				memcpy(kname, PATH_BOOT3, sizeof(PATH_BOOT3));
+			break;
+		}
+		autoboot = 0;
+
+		/*
+		 * Try to exec stage 3 boot loader. If interrupted by a
+		 * keypress, or in case of failure, try to load a kernel
+		 * directly instead.
+		 */
+		if (*kname != '\0')
+			load();
+		memcpy(kname, PATH_BOOT3, sizeof(PATH_BOOT3));
+		load();
+		memcpy(kname, PATH_KERNEL, sizeof(PATH_KERNEL));
+		load();
+		gptbootfailed(&dsk);
+		if (gptfind(&freebsd_ufs_uuid, &dsk, -1) == -1)
+			break;
+		dsk_meta = 0;
+	}
 
-    /*
-     * Try to exec stage 3 boot loader. If interrupted by a keypress,
-     * or in case of failure, try to load a kernel directly instead.
-     */
+	/* Present the user with the boot2 prompt. */
 
-    if (autoboot && !*kname) {
-	memcpy(kname, PATH_BOOT3, sizeof(PATH_BOOT3));
-	if (!keyhit(3*SECOND)) {
-	    load();
-	    memcpy(kname, PATH_KERNEL, sizeof(PATH_KERNEL));
+	for (;;) {
+		if (!OPT_CHECK(RBX_QUIET)) {
+			printf("\nFreeBSD/x86 boot\n"
+			    "Default: %u:%s(%up%u)%s\n"
+			    "boot: ",
+			    dsk.drive & DRV_MASK, dev_nm[dsk.type], dsk.unit,
+			    dsk.part, kname);
+		}
+		if (ioctrl & IO_SERIAL)
+			sio_flush();
+		*cmd = '\0';
+		if (keyhit(0))
+			getstr(cmd, sizeof(cmd));
+		else if (!OPT_CHECK(RBX_QUIET))
+			putchar('\n');
+		if (parse(cmd, &dskupdated)) {
+			putchar('\a');
+			continue;
+		}
+		if (dskupdated && gptinit() != 0)
+			continue;
+		load();
 	}
-    }
-
-    /* Present the user with the boot2 prompt. */
-
-    for (;;) {
-	if (!autoboot || !OPT_CHECK(RBX_QUIET))
-	    printf("\nFreeBSD/x86 boot\n"
-		   "Default: %u:%s(%up%u)%s\n"
-		   "boot: ",
-		   dsk.drive & DRV_MASK, dev_nm[dsk.type], dsk.unit,
-		   dsk.part, kname);
-	if (ioctrl & IO_SERIAL)
-	    sio_flush();
-	if (!autoboot || keyhit(5*SECOND))
-	    getstr();
-	else if (!autoboot || !OPT_CHECK(RBX_QUIET))
-	    putchar('\n');
-	autoboot = 0;
-	if (parse())
-	    putchar('\a');
-	else
-	    load();
-    }
+	/* NOTREACHED */
 }
 
 /* XXX - Needed for btxld to link the boot2 binary; do not remove. */
@@ -321,8 +251,11 @@ load(void)
     int fmt, i, j;
 
     if (!(ino = lookup(kname))) {
-	if (!ls)
-	    printf("No %s\n", kname);
+	if (!ls) {
+	    printf("%s: No %s on %u:%s(%up%u)\n", BOOTPROG,
+		kname, dsk.drive & DRV_MASK, dev_nm[dsk.type], dsk.unit,
+		dsk.part);
+	}
 	return;
     }
     if (xfsread(ino, &hdr, sizeof(hdr)))
@@ -402,14 +335,15 @@ load(void)
 }
 
 static int
-parse(void)
+parse(char *cmdstr, int *dskupdated)
 {
-    char *arg = cmd;
+    char *arg = cmdstr;
     char *ep, *p, *q;
     const char *cp;
     unsigned int drv;
     int c, i, j;
 
+    *dskupdated = 0;
     while ((c = *arg++)) {
 	if (c == ' ' || c == '\t' || c == '\n')
 	    continue;
@@ -480,7 +414,7 @@ parse(void)
 		    drv = dsk.unit;
 		dsk.drive = (dsk.type <= TYPE_MAXHARD
 			     ? DRV_HARD : 0) + drv;
-		dsk_meta = 0;
+		*dskupdated = 1;
 	    }
 	    if ((i = ep - arg)) {
 		if ((size_t)i >= sizeof(kname))
@@ -496,232 +430,6 @@ parse(void)
 static int
 dskread(void *buf, daddr_t lba, unsigned nblk)
 {
-    struct gpt_hdr hdr;
-    struct gpt_ent *ent;
-    char *sec;
-    daddr_t slba, elba;
-    int part, entries_per_sec;
-
-    if (!dsk_meta) {
-	/* Read and verify GPT. */
-	sec = dmadat->secbuf;
-	dsk.start = 0;
-	if (drvread(sec, 1, 1))
-	    return -1;
-	memcpy(&hdr, sec, sizeof(hdr));
-	if (bcmp(hdr.hdr_sig, GPT_HDR_SIG, sizeof(hdr.hdr_sig)) != 0 ||
-	    hdr.hdr_lba_self != 1 || hdr.hdr_revision < 0x00010000 ||
-	    hdr.hdr_entsz < sizeof(*ent) || DEV_BSIZE % hdr.hdr_entsz != 0) {
-	    printf("Invalid GPT header\n");
-	    return -1;
-	}
-
-	/* XXX: CRC check? */
-
-	/*
-	 * If the partition isn't specified, then search for the first UFS
-	 * partition and hope it is /.  Perhaps we should be using an OS
-	 * flag in the GPT entry to mark / partitions.
-	 *
-	 * If the partition is specified, then figure out the LBA for the
-	 * sector containing that partition index and load it.
-	 */
-	entries_per_sec = DEV_BSIZE / hdr.hdr_entsz;
-	if (dsk.part == -1) {
-	    slba = hdr.hdr_lba_table;
-	    elba = slba + hdr.hdr_entries / entries_per_sec;
-	    while (slba < elba && dsk.part == -1) {
-		if (drvread(sec, slba, 1))
-		    return -1;
-		for (part = 0; part < entries_per_sec; part++) {
-		    ent = (struct gpt_ent *)(sec + part * hdr.hdr_entsz);
-		    if (bcmp(&ent->ent_type, &freebsd_ufs_uuid,
-			sizeof(uuid_t)) == 0) {
-			dsk.part = (slba - hdr.hdr_lba_table) *
-			    entries_per_sec + part + 1;
-			dsk.start = ent->ent_lba_start;
-			break;
-		    }
-		}
-		slba++;
-	    }
-	    if (dsk.part == -1) {
-		printf("No UFS partition was found\n");
-		return -1;
-	    }
-	} else {
-	    if (dsk.part > hdr.hdr_entries) {
-		printf("Invalid partition index\n");
-		return -1;
-	    }
-	    slba = hdr.hdr_lba_table + (dsk.part - 1) / entries_per_sec;
-	    if (drvread(sec, slba, 1))
-		return -1;
-	    part = (dsk.part - 1) % entries_per_sec;
-	    ent = (struct gpt_ent *)(sec + part * hdr.hdr_entsz);
-	    if (bcmp(&ent->ent_type, &freebsd_ufs_uuid, sizeof(uuid_t)) != 0) {
-		printf("Specified partition is not UFS\n");
-		return -1;
-	    }
-	    dsk.start = ent->ent_lba_start;
-	}
-	/*
-	 * XXX: No way to detect SCSI vs. ATA currently.
-	 */
-#if 0
-	if (!dsk.init) {
-	    if (d->d_type == DTYPE_SCSI)
-		dsk.type = TYPE_DA;
-	    dsk.init++;
-	}
-#endif
-    }
-    return drvread(buf, dsk.start + lba, nblk);
-}
-
-static void
-printf(const char *fmt,...)
-{
-    va_list ap;
-    char buf[10];
-    char *s;
-    unsigned u;
-    int c;
-
-    va_start(ap, fmt);
-    while ((c = *fmt++)) {
-	if (c == '%') {
-	    c = *fmt++;
-	    switch (c) {
-	    case 'c':
-		putchar(va_arg(ap, int));
-		continue;
-	    case 's':
-		for (s = va_arg(ap, char *); *s; s++)
-		    putchar(*s);
-		continue;
-	    case 'u':
-		u = va_arg(ap, unsigned);
-		s = buf;
-		do
-		    *s++ = '0' + u % 10U;
-		while (u /= 10U);
-		while (--s >= buf)
-		    putchar(*s);
-		continue;
-	    }
-	}
-	putchar(c);
-    }
-    va_end(ap);
-    return;
-}
-
-static void
-putchar(int c)
-{
-    if (c == '\n')
-	xputc('\r');
-    xputc(c);
-}
-
-static int
-bcmp(const void *b1, const void *b2, size_t length)
-{
-    const char *p1 = b1, *p2 = b2;
-
-    if (length == 0)
-	return (0);
-    do {
-	if (*p1++ != *p2++)
-	    break;
-    } while (--length);
-    return (length);
-}
-
-static struct {
-	uint16_t len;
-	uint16_t count;
-	uint16_t off;
-	uint16_t seg;
-	uint64_t lba;
-} packet;
-
-static int
-drvread(void *buf, daddr_t lba, unsigned nblk)
-{
-    static unsigned c = 0x2d5c7c2f;
-
-    if (!OPT_CHECK(RBX_QUIET))
-	printf("%c\b", c = c << 8 | c >> 24);
-    packet.len = 0x10;
-    packet.count = nblk;
-    packet.off = VTOPOFF(buf);
-    packet.seg = VTOPSEG(buf);
-    packet.lba = lba;
-    v86.ctl = V86_FLAGS;
-    v86.addr = 0x13;
-    v86.eax = 0x4200;
-    v86.edx = dsk.drive;
-    v86.ds = VTOPSEG(&packet);
-    v86.esi = VTOPOFF(&packet);
-    v86int();
-    if (V86_CY(v86.efl)) {
-	printf("error %u lba %u\n", v86.eax >> 8 & 0xff, lba);
-	return -1;
-    }
-    return 0;
-}
 
-static int
-keyhit(unsigned ticks)
-{
-    uint32_t t0, t1;
-
-    if (OPT_CHECK(RBX_NOINTR))
-	return 0;
-    t0 = 0;
-    for (;;) {
-	if (xgetc(1))
-	    return 1;
-	t1 = *(uint32_t *)PTOV(0x46c);
-	if (!t0)
-	    t0 = t1;
-	if (t1 < t0 || t1 >= t0 + ticks)
-	    return 0;
-    }
-}
-
-static int
-xputc(int c)
-{
-    if (ioctrl & IO_KEYBOARD)
-	putc(c);
-    if (ioctrl & IO_SERIAL)
-	sio_putc(c);
-    return c;
-}
-
-static int
-xgetc(int fn)
-{
-    if (OPT_CHECK(RBX_NOINTR))
-	return 0;
-    for (;;) {
-	if (ioctrl & IO_KEYBOARD && getc(1))
-	    return fn ? 1 : getc(0);
-	if (ioctrl & IO_SERIAL && sio_ischar())
-	    return fn ? 1 : sio_getc();
-	if (fn)
-	    return 0;
-    }
-}
-
-static int
-getc(int fn)
-{
-    v86.addr = 0x16;
-    v86.eax = fn << 8;
-    v86int();
-    return fn == 0 ? v86.eax & 0xff : !V86_ZR(v86.efl);
+	return drvread(&dsk, buf, lba + dsk.start, nblk);
 }
diff --git a/sys/boot/i386/gptzfsboot/Makefile b/sys/boot/i386/gptzfsboot/Makefile
index cf7ff35..30a5fc7 100644
--- a/sys/boot/i386/gptzfsboot/Makefile
+++ b/sys/boot/i386/gptzfsboot/Makefile
@@ -1,6 +1,8 @@
 # $FreeBSD$
 
-.PATH:		${.CURDIR}/../boot2 ${.CURDIR}/../gptboot ${.CURDIR}/../zfsboot
+.PATH:		${.CURDIR}/../boot2 ${.CURDIR}/../gptboot \
+		${.CURDIR}/../zfsboot ${.CURDIR}/../common \
+		${.CURDIR}/../../common
 
 FILES=		gptzfsboot
 
@@ -14,7 +16,8 @@ REL1=	0x700
 ORG1=	0x7c00
 ORG2=	0x0
 
-CFLAGS=	-Os \
+CFLAGS=	-DBOOTPROG=\"gptzfsboot\" \
+	-Os \
 	-fno-guess-branch-probability \
 	-fomit-frame-pointer \
 	-fno-unit-at-a-time \
@@ -26,6 +29,7 @@ CFLAGS=	-Os \
 	-DSIOFMT=${B2SIOFMT} \
 	-DSIOSPD=${BOOT_COMCONSOLE_SPEED} \
 	-I${.CURDIR}/../../common \
+	-I${.CURDIR}/../common \
 	-I${.CURDIR}/../../zfs \
 	-I${.CURDIR}/../../../cddl/boot/zfs \
 	-I${.CURDIR}/../btx/lib -I. \
@@ -59,7 +63,7 @@ CLEANFILES+=	gptzfsboot.bin gptzfsboot.out zfsboot.o sio.o
 gptzfsboot.bin: gptzfsboot.out
 	objcopy -S -O binary gptzfsboot.out ${.TARGET}
 
-gptzfsboot.out: ${BTXCRT} zfsboot.o sio.o
+gptzfsboot.out: ${BTXCRT} zfsboot.o sio.o gpt.o drv.o cons.o util.o
 	${LD} ${LDFLAGS} -Ttext ${ORG2} -o ${.TARGET} ${.ALLSRC} ${LIBSTAND}
 
 zfsboot.o: ${.CURDIR}/../../zfs/zfsimpl.c
diff --git a/sys/boot/i386/zfsboot/Makefile b/sys/boot/i386/zfsboot/Makefile
index 7e5cb56..10616e4 100644
--- a/sys/boot/i386/zfsboot/Makefile
+++ b/sys/boot/i386/zfsboot/Makefile
@@ -1,6 +1,6 @@
 # $FreeBSD$
 
-.PATH:		${.CURDIR}/../boot2
+.PATH:		${.CURDIR}/../boot2 ${.CURDIR}/../common ${.CURDIR}/../../common
 
 FILES=		zfsboot
 
@@ -17,7 +17,8 @@ REL1=	0x700
 ORG1=	0x7c00
 ORG2=	0x2000
 
-CFLAGS=	-Os -g \
+CFLAGS=	-DBOOTPROG=\"zfsboot\" \
+	-Os -g \
 	-fno-guess-branch-probability \
 	-fomit-frame-pointer \
 	-fno-unit-at-a-time \
@@ -29,6 +30,8 @@ CFLAGS=	-Os -g \
 	-DSIOPRT=${BOOT_COMCONSOLE_PORT} \
 	-DSIOFMT=${B2SIOFMT} \
 	-DSIOSPD=${BOOT_COMCONSOLE_SPEED} \
+	-I${.CURDIR}/../../common \
+	-I${.CURDIR}/../common \
 	-I${.CURDIR}/../../zfs \
 	-I${.CURDIR}/../../../cddl/boot/zfs \
 	-I${.CURDIR}/../btx/lib -I. \
@@ -57,7 +60,7 @@ zfsldr.out: zfsldr.o
 	${LD} ${LDFLAGS} -e start -Ttext ${ORG1} -o ${.TARGET} zfsldr.o
 
 CLEANFILES+=	zfsboot2 zfsboot.ld zfsboot.ldr zfsboot.bin zfsboot.out \
-		zfsboot.o zfsboot.s zfsboot.s.tmp zfsboot.h sio.o
+		zfsboot.o zfsboot.s zfsboot.s.tmp xreadorg.h sio.o
 
 # We currently allow 32768 bytes for zfsboot - in practice it could be
 # any size up to 3.5Mb but keeping it fixed size simplifies zfsldr.
@@ -79,19 +82,19 @@ zfsboot.ldr:
 zfsboot.bin: zfsboot.out
 	objcopy -S -O binary zfsboot.out ${.TARGET}
 
-zfsboot.out: ${BTXCRT} zfsboot.o sio.o
+zfsboot.out: ${BTXCRT} zfsboot.o sio.o drv.o cons.o util.o
 	${LD} ${LDFLAGS} -Ttext ${ORG2} -o ${.TARGET} ${.ALLSRC} ${LIBSTAND}
 
 zfsboot.o: zfsboot.s
 
-SRCS=	zfsboot.c zfsboot.h
+SRCS=	zfsboot.c xreadorg.h
 
-zfsboot.s: zfsboot.c zfsboot.h ${.CURDIR}/../../zfs/zfsimpl.c
+zfsboot.s: zfsboot.c xreadorg.h ${.CURDIR}/../../zfs/zfsimpl.c
 	${CC} ${CFLAGS} -S -o zfsboot.s.tmp ${.CURDIR}/zfsboot.c
 	sed -e '/align/d' -e '/nop/d' < zfsboot.s.tmp > zfsboot.s
 	rm -f zfsboot.s.tmp
 
-zfsboot.h: zfsldr.out
+xreadorg.h: zfsldr.out
 	${NM} -t d ${.ALLSRC} | awk '/([0-9])+ T xread/ \
 	    { x = $$1 - ORG1; \
 	    printf("#define XREADORG %#x\n", REL1 + x) }' \
diff --git a/sys/boot/i386/zfsboot/zfsboot.c b/sys/boot/i386/zfsboot/zfsboot.c
index c6ef699..1d0077b 100644
--- a/sys/boot/i386/zfsboot/zfsboot.c
+++ b/sys/boot/i386/zfsboot/zfsboot.c
@@ -36,50 +36,11 @@ __FBSDID("$FreeBSD$");
 
 #include <btxv86.h>
 
-#ifndef GPT
-#include "zfsboot.h"
-#endif
 #include "lib.h"
-
-#define IO_KEYBOARD	1
-#define IO_SERIAL	2
-
-#define SECOND		18	/* Circa that many ticks in a second. */
-
-#define RBX_ASKNAME	0x0	/* -a */
-#define RBX_SINGLE	0x1	/* -s */
-/* 0x2 is reserved for log2(RB_NOSYNC). */
-/* 0x3 is reserved for log2(RB_HALT). */
-/* 0x4 is reserved for log2(RB_INITNAME). */
-#define RBX_DFLTROOT	0x5	/* -r */
-#define RBX_KDB 	0x6	/* -d */
-/* 0x7 is reserved for log2(RB_RDONLY). */
-/* 0x8 is reserved for log2(RB_DUMP). */
-/* 0x9 is reserved for log2(RB_MINIROOT). */
-#define RBX_CONFIG	0xa	/* -c */
-#define RBX_VERBOSE	0xb	/* -v */
-#define RBX_SERIAL	0xc	/* -h */
-#define RBX_CDROM	0xd	/* -C */
-/* 0xe is reserved for log2(RB_POWEROFF). */
-#define RBX_GDB 	0xf	/* -g */
-#define RBX_MUTE	0x10	/* -m */
-/* 0x11 is reserved for log2(RB_SELFTEST). */
-/* 0x12 is reserved for boot programs. */
-/* 0x13 is reserved for boot programs. */
-#define RBX_PAUSE	0x14	/* -p */
-#define RBX_QUIET	0x15	/* -q */
-#define RBX_NOINTR	0x1c	/* -n */
-/* 0x1d is reserved for log2(RB_MULTIPLE) and is just misnamed here. */
-#define RBX_DUAL	0x1d	/* -D */
-/* 0x1f is reserved for log2(RB_BOOTINFO). */
-
-/* pass: -a, -s, -r, -d, -c, -v, -h, -C, -g, -m, -p, -D */
-#define RBX_MASK	(OPT_SET(RBX_ASKNAME) | OPT_SET(RBX_SINGLE) | \
-			OPT_SET(RBX_DFLTROOT) | OPT_SET(RBX_KDB ) | \
-			OPT_SET(RBX_CONFIG) | OPT_SET(RBX_VERBOSE) | \
-			OPT_SET(RBX_SERIAL) | OPT_SET(RBX_CDROM) | \
-			OPT_SET(RBX_GDB ) | OPT_SET(RBX_MUTE) | \
-			OPT_SET(RBX_PAUSE) | OPT_SET(RBX_DUAL))
+#include "rbx.h"
+#include "drv.h"
+#include "util.h"
+#include "cons.h"
 
 /* Hint to loader that we came from ZFS */
 #define	KARGS_FLAGS_ZFS		0x4
@@ -91,8 +52,6 @@ __FBSDID("$FreeBSD$");
 #define ARGS		0x900
 #define NOPT		14
 #define NDEV		3
-#define V86_CY(x)	((x) & 1)
-#define V86_ZR(x)	((x) & 0x40)
 
 #define BIOS_NUMDRIVES	0x475
 #define DRV_HARD	0x80
@@ -103,8 +62,7 @@ __FBSDID("$FreeBSD$");
 #define TYPE_MAXHARD	TYPE_DA
 #define TYPE_FD		2
 
-#define OPT_SET(opt)	(1 << (opt))
-#define OPT_CHECK(opt)	((opts) & OPT_SET(opt))
+#define	MAXBDDEV	31
 
 extern uint32_t _end;
 
@@ -128,26 +86,16 @@ static const unsigned char flags[NOPT] = {
     RBX_SINGLE,
     RBX_VERBOSE
 };
+uint32_t opts;
 
 static const char *const dev_nm[NDEV] = {"ad", "da", "fd"};
 static const unsigned char dev_maj[NDEV] = {30, 4, 2};
 
-struct dsk {
-    unsigned drive;
-    unsigned type;
-    unsigned unit;
-    unsigned slice;
-    unsigned part;
-    int init;
-    daddr_t start;
-};
 static char cmd[512];
 static char kname[1024];
-static uint32_t opts;
 static int comspeed = SIOSPD;
 static struct bootinfo bootinfo;
 static uint32_t bootdev;
-static uint8_t ioctrl = IO_KEYBOARD;
 
 vm_offset_t	high_heap_base;
 uint32_t	bios_basemem, bios_extmem, high_heap_size;
@@ -173,79 +121,7 @@ static struct dmadat *dmadat;
 void exit(int);
 static void load(void);
 static int parse(void);
-static void printf(const char *,...);
-static void putchar(int);
 static void bios_getmem(void);
-static int drvread(struct dsk *, void *, daddr_t, unsigned);
-static int keyhit(unsigned);
-static int xputc(int);
-static int xgetc(int);
-static int getc(int);
-
-static void memcpy(void *, const void *, int);
-static void
-memcpy(void *dst, const void *src, int len)
-{
-    const char *s = src;
-    char *d = dst;
-
-    while (len--)
-        *d++ = *s++;
-}
-
-static void
-strcpy(char *dst, const char *src)
-{
-    while (*src)
-	*dst++ = *src++;
-    *dst++ = 0;
-}
-
-static void
-strcat(char *dst, const char *src)
-{
-    while (*dst)
-	dst++;
-    while (*src)
-	*dst++ = *src++;
-    *dst++ = 0;
-}
-
-static int
-strcmp(const char *s1, const char *s2)
-{
-    for (; *s1 == *s2 && *s1; s1++, s2++);
-    return (unsigned char)*s1 - (unsigned char)*s2;
-}
-
-static const char *
-strchr(const char *s, char ch)
-{
-    for (; *s; s++)
-	if (*s == ch)
-		return s;
-    return 0;
-}
-
-static int
-memcmp(const void *p1, const void *p2, size_t n)
-{
-    const char *s1 = (const char *) p1;
-    const char *s2 = (const char *) p2;
-    for (; n > 0 && *s1 == *s2; s1++, s2++, n--);
-    if (n)
-        return (unsigned char)*s1 - (unsigned char)*s2;
-    else
-	return 0;
-}
-
-static void
-memset(void *p, char val, size_t n)
-{
-    char *s = (char *) p;
-    while (n--)
-	*s++ = val;
-}
 
 static void *
 malloc(size_t n)
@@ -261,15 +137,6 @@ malloc(size_t n)
 	return p;
 }
 
-static size_t
-strlen(const char *s)
-{
-	size_t len = 0;
-	while (*s++)
-		len++;
-	return len;
-}
-
 static char *
 strdup(const char *s)
 {
@@ -324,6 +191,7 @@ vdev_read(vdev_t *vdev, void *priv, off_t off, void *buf, size_t bytes)
 
 	p = buf;
 	lba = off / DEV_BSIZE;
+	lba += dsk->start;
 	while (bytes > 0) {
 		nb = bytes / DEV_BSIZE;
 		if (nb > READ_BUF_SIZE / DEV_BSIZE)
@@ -435,46 +303,6 @@ bios_getmem(void)
     }
 }    
 
-static inline void
-getstr(void)
-{
-    char *s;
-    int c;
-
-    s = cmd;
-    for (;;) {
-	switch (c = xgetc(0)) {
-	case 0:
-	    break;
-	case '\177':
-	case '\b':
-	    if (s > cmd) {
-		s--;
-		printf("\b \b");
-	    }
-	    break;
-	case '\n':
-	case '\r':
-	    *s = 0;
-	    return;
-	default:
-	    if (s - cmd < sizeof(cmd) - 1)
-		*s++ = c;
-	    putchar(c);
-	}
-    }
-}
-
-static inline void
-putc(int c)
-{
-    v86.ctl = 0;
-    v86.addr = 0x10;
-    v86.eax = 0xe00 | (c & 0xff);
-    v86.ebx = 0x7;
-    v86int();
-}
-
 /*
  * Try to detect a device supported by the legacy int13 BIOS
  */
@@ -571,7 +399,7 @@ probe_drive(struct dsk *dsk, spa_t **spap)
 		     * We record the first pool we find (we will try
 		     * to boot from that one).
 		     */
-		    spap = 0;
+		    spap = NULL;
 
 		    /*
 		     * This slice had a vdev. We need a new dsk
@@ -687,7 +515,7 @@ main(void)
 	dsk->part = 0;
 	dsk->start = 0;
 	dsk->init = 0;
-	probe_drive(dsk, 0);
+	probe_drive(dsk, NULL);
     }
 
     /*
@@ -697,7 +525,7 @@ main(void)
     if (!spa) {
 	spa = STAILQ_FIRST(&zfs_pools);
 	if (!spa) {
-	    printf("No ZFS pools located, can't boot\n");
+	    printf("%s: No ZFS pools located, can't boot\n", BOOTPROG);
 	    for (;;)
 		;
 	}
@@ -726,7 +554,7 @@ main(void)
 
     if (autoboot && !*kname) {
 	memcpy(kname, PATH_BOOT3, sizeof(PATH_BOOT3));
-	if (!keyhit(3*SECOND)) {
+	if (!keyhit(3)) {
 	    load();
 	    memcpy(kname, PATH_KERNEL, sizeof(PATH_KERNEL));
 	}
@@ -742,8 +570,8 @@ main(void)
 		   spa->spa_name, kname);
 	if (ioctrl & IO_SERIAL)
 	    sio_flush();
-	if (!autoboot || keyhit(5*SECOND))
-	    getstr();
+	if (!autoboot || keyhit(5))
+	    getstr(cmd, sizeof(cmd));
 	else if (!autoboot || !OPT_CHECK(RBX_QUIET))
 	    putchar('\n');
 	autoboot = 0;
@@ -858,7 +686,7 @@ load(void)
 }
 
 static int
-parse()
+parse(void)
 {
     char *arg = cmd;
     char *ep, *p, *q;
@@ -950,222 +778,3 @@ parse()
     }
     return 0;
 }
-
-static void
-printf(const char *fmt,...)
-{
-    va_list ap;
-    char buf[20];
-    char *s;
-    unsigned long long u;
-    int c;
-    int minus;
-    int prec;
-    int l;
-    int len;
-    int pad;
-
-    va_start(ap, fmt);
-    while ((c = *fmt++)) {
-	if (c == '%') {
-	    minus = 0;
-	    prec = 0;
-	    l = 0;
-	nextfmt:
-	    c = *fmt++;
-	    switch (c) {
-	    case '-':
-		minus = 1;
-		goto nextfmt;
-	    case '0':
-	    case '1':
-	    case '2':
-	    case '3':
-	    case '4':
-	    case '5':
-	    case '6':
-	    case '7':
-	    case '8':
-	    case '9':
-		prec = 10 * prec + (c - '0');
-		goto nextfmt;
-	    case 'c':
-		putchar(va_arg(ap, int));
-		continue;
-	    case 'l':
-		l++;
-		goto nextfmt;
-	    case 's':
-		s = va_arg(ap, char *);
-		if (prec) {
-		    len = strlen(s);
-		    if (len < prec)
-			pad = prec - len;
-		    else
-			pad = 0;
-		    if (minus)
-			while (pad--)
-			    putchar(' ');
-		    for (; *s; s++)
-			putchar(*s);
-		    if (!minus)
-			while (pad--)
-			    putchar(' ');
-		} else {
-		    for (; *s; s++)
-			putchar(*s);
-		}
-		continue;
-	    case 'u':
-		switch (l) {
-		case 2:
-		    u = va_arg(ap, unsigned long long);
-		    break;
-		case 1:
-		    u = va_arg(ap, unsigned long);
-		    break;
-		default:
-		    u = va_arg(ap, unsigned);
-		    break;
-		}
-		s = buf;
-		do
-		    *s++ = '0' + u % 10U;
-		while (u /= 10U);
-		while (--s >= buf)
-		    putchar(*s);
-		continue;
-	    }
-	}
-	putchar(c);
-    }
-    va_end(ap);
-    return;
-}
-
-static void
-putchar(int c)
-{
-    if (c == '\n')
-	xputc('\r');
-    xputc(c);
-}
-
-#ifdef GPT
-static struct {
-	uint16_t len;
-	uint16_t count;
-	uint16_t off;
-	uint16_t seg;
-	uint64_t lba;
-} packet;
-#endif
-
-static int
-drvread(struct dsk *dsk, void *buf, daddr_t lba, unsigned nblk)
-{
-#ifdef GPT
-    static unsigned c = 0x2d5c7c2f;
-
-    if (!OPT_CHECK(RBX_QUIET))
-	printf("%c\b", c = c << 8 | c >> 24);
-    packet.len = 0x10;
-    packet.count = nblk;
-    packet.off = VTOPOFF(buf);
-    packet.seg = VTOPSEG(buf);
-    packet.lba = lba + dsk->start;
-    v86.ctl = V86_FLAGS;
-    v86.addr = 0x13;
-    v86.eax = 0x4200;
-    v86.edx = dsk->drive;
-    v86.ds = VTOPSEG(&packet);
-    v86.esi = VTOPOFF(&packet);
-    v86int();
-    if (V86_CY(v86.efl)) {
-	printf("error %u lba %u\n", v86.eax >> 8 & 0xff, lba);
-	return -1;
-    }
-    return 0;
-#else
-    static unsigned c = 0x2d5c7c2f;
-
-    lba += dsk->start;
-    if (!OPT_CHECK(RBX_QUIET))
-	printf("%c\b", c = c << 8 | c >> 24);
-    v86.ctl = V86_ADDR | V86_CALLF | V86_FLAGS;
-    v86.addr = XREADORG;		/* call to xread in boot1 */
-    v86.es = VTOPSEG(buf);
-    v86.eax = lba;
-    v86.ebx = VTOPOFF(buf);
-    v86.ecx = lba >> 32;
-    v86.edx = nblk << 8 | dsk->drive;
-    v86int();
-    v86.ctl = V86_FLAGS;
-    if (V86_CY(v86.efl)) {
-	printf("error %u lba %u\n", v86.eax >> 8 & 0xff, lba);
-	return -1;
-    }
-    return 0;
-#endif
-}
-
-static int
-keyhit(unsigned ticks)
-{
-    uint32_t t0, t1;
-
-    if (OPT_CHECK(RBX_NOINTR))
-	return 0;
-    t0 = 0;
-    for (;;) {
-	if (xgetc(1))
-	    return 1;
-	t1 = *(uint32_t *)PTOV(0x46c);
-	if (!t0)
-	    t0 = t1;
-	if (t1 < t0 || t1 >= t0 + ticks)
-	    return 0;
-    }
-}
-
-static int
-xputc(int c)
-{
-    if (ioctrl & IO_KEYBOARD)
-	putc(c);
-    if (ioctrl & IO_SERIAL)
-	sio_putc(c);
-    return c;
-}
-
-static int
-xgetc(int fn)
-{
-    if (OPT_CHECK(RBX_NOINTR))
-	return 0;
-    for (;;) {
-	if (ioctrl & IO_KEYBOARD && getc(1))
-	    return fn ? 1 : getc(0);
-	if (ioctrl & IO_SERIAL && sio_ischar())
-	    return fn ? 1 : sio_getc();
-	if (fn)
-	    return 0;
-    }
-}
-
-static int
-getc(int fn)
-{
-    /*
-     * The extra comparison against zero is an attempt to work around
-     * what appears to be a bug in QEMU and Bochs. Both emulators
-     * sometimes report a key-press with scancode one and ascii zero
-     * when no such key is pressed in reality. As far as I can tell,
-     * this only happens shortly after a reboot.
-     */
-    v86.ctl = V86_FLAGS;
-    v86.addr = 0x16;
-    v86.eax = fn << 8;
-    v86int();
-    return fn == 0 ? v86.eax & 0xff : (!V86_ZR(v86.efl) && (v86.eax & 0xff));
-}
diff --git a/sys/boot/zfs/Makefile b/sys/boot/zfs/Makefile
index beba733..91525d7 100644
--- a/sys/boot/zfs/Makefile
+++ b/sys/boot/zfs/Makefile
@@ -5,6 +5,7 @@ INTERNALLIB=
 
 SRCS+=		zfs.c
 
+CFLAGS+=	-DBOOTPROG=\"zfsloader\"
 CFLAGS+=	-I${.CURDIR}/../common -I${.CURDIR}/../.. -I.
 CFLAGS+=	-I${.CURDIR}/../../../lib/libstand
 CFLAGS+=	-I${.CURDIR}/../../cddl/boot/zfs
diff --git a/sys/boot/zfs/zfsimpl.c b/sys/boot/zfs/zfsimpl.c
index f5eff62..cb09120 100644
--- a/sys/boot/zfs/zfsimpl.c
+++ b/sys/boot/zfs/zfsimpl.c
@@ -496,12 +496,7 @@ vdev_init_from_nvlist(const unsigned char *nvlist, vdev_t **vdevp, int is_newer)
 			vdev->v_nparity = 0;
 		if (nvlist_find(nvlist, ZPOOL_CONFIG_PATH,
 				DATA_TYPE_STRING, 0, &path) == 0) {
-			if (strlen(path) > 5
-			    && path[0] == '/'
-			    && path[1] == 'd'
-			    && path[2] == 'e'
-			    && path[3] == 'v'
-			    && path[4] == '/')
+			if (strncmp(path, "/dev/", 5) == 0)
 				path += 5;
 			vdev->v_name = strdup(path);
 		} else {
@@ -682,7 +677,7 @@ pager_printf(const char *fmt, ...)
 
 #endif
 
-#define STATUS_FORMAT	"        %-16s %-10s\n"
+#define STATUS_FORMAT	"        %s %s\n"
 
 static void
 print_state(int indent, const char *name, vdev_state_t state)
@@ -1393,7 +1388,7 @@ fzap_list(spa_t *spa, const dnode_phys_t *dnode)
 			 */
 			value = fzap_leaf_value(&zl, zc);
 
-			printf("%-32s 0x%llx\n", name, value);
+			printf("%s 0x%llx\n", name, value);
 		}
 	}