Add support to GEOM for GUID Partition Tables (GPTs). The support

is currently conditional on both the GEOM and GEOM_GPT options to
avoid getting GPT by default and having the MBR and GPT classes
clash.
The correct behaviour of the MBR class would be to back-off (reject)
a MBR if it's a Protective MBR (a MBR with a single partition of type
0xEE that spans the whole disk (as far as the MBR is concerned).
The correct behaviour if the GPT class would be to back-off (reject)
a GPT if there's a MBR that's not a Protective MBR.

At this stage it's inconvenient to destroy a good MBR when working
with GPTs that it's more convenient to have the MBR class back-off
when it detects the GPT signature on disk and have the GPT class
ignore the MBR.

In sys/gpt.h UUIDs (GUIDs) for the following FreeBSD partitions
have been defined:

GPT_ENT_TYPE_FREEBSD
	FreeBSD slice with disklabel. This is the equivalent of
	the well-known FreeBSD MBR partition type.
GPT_ENT_TYPE_FREEBSD_{SWAP|UFS|UFS2|VINUM}
	FreeBSD partitions in the context of disklabel. This is
	speculating on the idea to use the GPT to hold partitions
	instead if slices and removing the fixed (and low) limits
	we have on the number of partitions.

This commit lacks a GPT image for the regression suite.

1 files changed, 78 insertions, 0 deletions

diff --git a/sys/sys/gpt.h b/sys/sys/gpt.h
new file mode 100644
index 000000000000..813a4f166691
--- /dev/null
+++ b/sys/sys/gpt.h
@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2002 Marcel Moolenaar
+ * 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 AUTHOR ``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 AUTHOR 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 _SYS_GPT_H_
+#define	_SYS_GPT_H_
+
+struct gpt_hdr {
+	char		hdr_sig[8];
+#define	GPT_HDR_SIG		"EFI PART"
+	uint32_t	hdr_revision;
+#define	GPT_HDR_REVISION	0x00010000
+	uint32_t	hdr_size;
+	uint32_t	hdr_crc_self;
+	uint32_t	__reserved;
+	uint64_t	hdr_lba_self;
+	uint64_t	hdr_lba_alt;
+	uint64_t	hdr_lba_start;
+	uint64_t	hdr_lba_end;
+	struct uuid	hdr_uuid;
+	uint64_t	hdr_lba_table;
+	uint32_t	hdr_entries;
+	uint32_t	hdr_entsz;
+	uint32_t	hdr_crc_table;
+};
+
+struct gpt_ent {
+	struct uuid	ent_type;
+	struct uuid	ent_uuid;
+	uint64_t	ent_lba_start;
+	uint64_t	ent_lba_end;
+	uint64_t	ent_attr;
+#define	GPT_ENT_ATTR_PLATFORM		(1ULL << 0)
+	short		ent_name[36];		/* UNICODE!!! */
+};
+
+#define	GPT_ENT_TYPE_UNUSED		\
+	{0x00000000,0x0000,0x0000,0x00,0x00,{0x00,0x00,0x00,0x00,0x00,0x00}}
+#define	GPT_ENT_TYPE_EFI		\
+	{0xc12a7328,0xf81f,0x11d2,0xba,0x4b,{0x00,0xa0,0xc9,0x3e,0xc9,0x3b}}
+#define	GPT_ENT_TYPE_MBR		\
+	{0x024dee41,0x33e7,0x11d3,0x9d,0x69,{0x00,0x08,0xc7,0x81,0xf3,0x9f}}
+#define	GPT_ENT_TYPE_FREEBSD		\
+	{0x516e7cb4,0x6ecf,0x11d6,0x8f,0xf8,{0x00,0x02,0x2d,0x09,0x71,0x2b}}
+#define	GPT_ENT_TYPE_FREEBSD_SWAP	\
+	{0x516e7cb5,0x6ecf,0x11d6,0x8f,0xf8,{0x00,0x02,0x2d,0x09,0x71,0x2b}}
+#define	GPT_ENT_TYPE_FREEBSD_UFS	\
+	{0x516e7cb6,0x6ecf,0x11d6,0x8f,0xf8,{0x00,0x02,0x2d,0x09,0x71,0x2b}}
+#define	GPT_ENT_TYPE_FREEBSD_UFS2	\
+	{0x516e7cb7,0x6ecf,0x11d6,0x8f,0xf8,{0x00,0x02,0x2d,0x09,0x71,0x2b}}
+#define	GPT_ENT_TYPE_FREEBSD_VINUM	\
+	{0x516e7cb8,0x6ecf,0x11d6,0x8f,0xf8,{0x00,0x02,0x2d,0x09,0x71,0x2b}}
+
+#endif /* _SYS_GPT_H_ */