[PATCH] EFI GUID partition table support.

EFI GUID partition table support from Matt Domsch

Documentation/kernel-parameters.txt

@@ -17,6 +17,7 @@ restrictions referred to are that the relevant option is valid if:
 	CD	Appropriate CD support is enabled.
 	DEVFS   devfs support is enabled. 
 	DRM	Direct Rendering Management support is enabled. 
+	EFI	EFI Partitioning (GPT) is enabled
 	EIDE	EIDE/ATAPI support is enabled.
 	FB	The frame buffer device is enabled.
 	HW	Appropriate hardware is enabled.
@@ -219,6 +220,9 @@ running once the system is up.
  
 	gdth=		[HW,SCSI]
 
+	gpt             [EFI] Forces disk with valid GPT signature but
+			invalid Protective MBR to be treated as GPT.
+
 	gscd=		[HW,CD]
 
 	gus=		[HW,SOUND] 

fs/partitions/Config.help

@@ -115,6 +115,11 @@ CONFIG_SGI_PARTITION
   Say Y here if you would like to be able to read the hard disk
   partition table format used by SGI machines.
 
+CONFIG_EFI_PARTITION
+  Say Y here if you would like to use hard disks under Linux which
+  were partitioned using EFI GPT.  Presently only useful on the
+  IA-64 platform.
+
 CONFIG_ULTRIX_PARTITION
   Say Y here if you would like to be able to read the hard disk
   partition table format used by DEC (now Compaq) Ultrix machines.

fs/partitions/Config.in

@@ -32,6 +32,7 @@ if [ "$CONFIG_PARTITION_ADVANCED" = "y" ]; then
    bool '  SGI partition support' CONFIG_SGI_PARTITION
    bool '  Ultrix partition table support' CONFIG_ULTRIX_PARTITION
    bool '  Sun partition tables support' CONFIG_SUN_PARTITION
+   bool '  EFI GUID Partition support' CONFIG_EFI_PARTITION
 else
    if [ "$ARCH" = "alpha" ]; then
       define_bool CONFIG_OSF_PARTITION y

fs/partitions/Makefile

@@ -24,6 +24,7 @@ obj-$(CONFIG_SGI_PARTITION) += sgi.o
 obj-$(CONFIG_SUN_PARTITION) += sun.o
 obj-$(CONFIG_ULTRIX_PARTITION) += ultrix.o
 obj-$(CONFIG_IBM_PARTITION) += ibm.o
+obj-$(CONFIG_EFI_PARTITION) += efi.o
 
 include $(TOPDIR)/Rules.make
 

fs/partitions/check.c

@@ -35,6 +35,7 @@
 #include "sun.h"
 #include "ibm.h"
 #include "ultrix.h"
+#include "efi.h"
 
 int warn_no_part = 1; /*This is ugly: should make genhd removable media aware*/
 
@@ -43,6 +44,9 @@ static int (*check_part[])(struct gendisk *hd, struct block_device *bdev,
 #ifdef CONFIG_ACORN_PARTITION
 	acorn_partition,
 #endif
+#ifdef CONFIG_EFI_PARTITION
+	efi_partition,		/* this must come before msdos */
+#endif
 #ifdef CONFIG_LDM_PARTITION
 	ldm_partition,		/* this must come before msdos */
 #endif

fs/partitions/efi.h

+/************************************************************
+ * EFI GUID Partition Table
+ * Per Intel EFI Specification v1.02
+ * http://developer.intel.com/technology/efi/efi.htm
+ *
+ * By Matt Domsch <Matt_Domsch@dell.com>  Fri Sep 22 22:15:56 CDT 2000  
+ *   Copyright 2000,2001 Dell Computer Corporation
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ * 
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ * 
+ ************************************************************/
+
+#ifndef FS_PART_EFI_H_INCLUDED
+#define FS_PART_EFI_H_INCLUDED
+
+#include <linux/types.h>
+#include <linux/config.h>
+#include <linux/fs.h>
+#include <linux/genhd.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/string.h>
+#include <linux/blk.h>
+/*
+ * Yes, specifying asm-ia64 is ugly, but this lets it build on
+ * other platforms too, until efi.h moves to include/linux.
+ */
+#include <asm-ia64/efi.h>
+
+#define MSDOS_MBR_SIGNATURE 0xaa55
+#define EFI_PMBR_OSTYPE_EFI 0xEF
+#define EFI_PMBR_OSTYPE_EFI_GPT 0xEE
+
+#define GPT_BLOCK_SIZE 512
+#define GPT_HEADER_SIGNATURE 0x5452415020494645L
+#define GPT_HEADER_REVISION_V1 0x00010000
+#define GPT_PRIMARY_PARTITION_TABLE_LBA 1
+
+#define UNUSED_ENTRY_GUID    \
+    ((efi_guid_t) { 0x00000000, 0x0000, 0x0000, { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }})
+#define PARTITION_SYSTEM_GUID \
+((efi_guid_t) { 0xC12A7328, 0xF81F, 0x11d2, { 0xBA, 0x4B, 0x00, 0xA0, 0xC9, 0x3E, 0xC9, 0x3B }})
+#define LEGACY_MBR_PARTITION_GUID \
+    ((efi_guid_t) { 0x024DEE41, 0x33E7, 0x11d3, { 0x9D, 0x69, 0x00, 0x08, 0xC7, 0x81, 0xF3, 0x9F }})
+#define PARTITION_MSFT_RESERVED_GUID \
+    ((efi_guid_t) { 0xE3C9E316, 0x0B5C, 0x4DB8, { 0x81, 0x7D, 0xF9, 0x2D, 0xF0, 0x02, 0x15, 0xAE }})
+#define PARTITION_BASIC_DATA_GUID \
+    ((efi_guid_t) { 0xEBD0A0A2, 0xB9E5, 0x4433, { 0x87, 0xC0, 0x68, 0xB6, 0xB7, 0x26, 0x99, 0xC7 }})
+#define PARTITION_LINUX_RAID_GUID \
+    ((efi_guid_t) { 0xa19d880f, 0x05fc, 0x4d3b, { 0xa0, 0x06, 0x74, 0x3f, 0x0f, 0x84, 0x91, 0x1e  }})
+#define PARTITION_LINUX_SWAP_GUID \
+    ((efi_guid_t) { 0x0657fd6d, 0xa4ab, 0x43c4, { 0x84, 0xe5, 0x09, 0x33, 0xc8, 0x4b, 0x4f, 0x4f  }})
+#define PARTITION_LINUX_LVM_GUID \
+    ((efi_guid_t) { 0xe6d6d379, 0xf507, 0x44c2, { 0xa2, 0x3c, 0x23, 0x8f, 0x2a, 0x3d, 0xf9, 0x28 }})
+
+typedef struct _gpt_header {
+	u64 signature;
+	u32 revision;
+	u32 header_size;
+	u32 header_crc32;
+	u32 reserved1;
+	u64 my_lba;
+	u64 alternate_lba;
+	u64 first_usable_lba;
+	u64 last_usable_lba;
+	efi_guid_t disk_guid;
+	u64 partition_entry_lba;
+	u32 num_partition_entries;
+	u32 sizeof_partition_entry;
+	u32 partition_entry_array_crc32;
+	u8 reserved2[GPT_BLOCK_SIZE - 92];
+} __attribute__ ((packed)) gpt_header;
+
+typedef struct _gpt_entry_attributes {
+	u64 required_to_function:1;
+	u64 reserved:47;
+        u64 type_guid_specific:16;
+} __attribute__ ((packed)) gpt_entry_attributes;
+
+typedef struct _gpt_entry {
+	efi_guid_t partition_type_guid;
+	efi_guid_t unique_partition_guid;
+	u64 starting_lba;
+	u64 ending_lba;
+	gpt_entry_attributes attributes;
+	efi_char16_t partition_name[72 / sizeof (efi_char16_t)];
+} __attribute__ ((packed)) gpt_entry;
+
+typedef struct _legacy_mbr {
+	u8 boot_code[440];
+	u32 unique_mbr_signature;
+	u16 unknown;
+	struct partition partition_record[4];
+	u16 signature;
+} __attribute__ ((packed)) legacy_mbr;
+
+/* Functions */
+extern int
+ efi_partition(struct gendisk *hd, struct block_device *bdev,
+	      unsigned long first_sector, int first_part_minor);
+
+#endif
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * --------------------------------------------------------------------------
+ * Local variables:
+ * c-indent-level: 4 
+ * c-brace-imaginary-offset: 0
+ * c-brace-offset: -4
+ * c-argdecl-indent: 4
+ * c-label-offset: -4
+ * c-continued-statement-offset: 4
+ * c-continued-brace-offset: 0
+ * indent-tabs-mode: nil
+ * tab-width: 8
+ * End:
+ */

fs/partitions/msdos.c

@@ -41,6 +41,7 @@ EXPORT_SYMBOL(ide_xlate_1024_hook);
 
 #include "check.h"
 #include "msdos.h"
+#include "efi.h"
 
 #if CONFIG_BLK_DEV_MD
 extern void md_autodetect_dev(kdev_t dev);
@@ -536,6 +537,16 @@ int msdos_partition(struct gendisk *hd, struct block_device *bdev,
 		return 0;
 	}
 	p = (struct partition *) (data + 0x1be);
+#ifdef CONFIG_EFI_PARTITION
+	for (i=1 ; i<=4 ; i++,p++) {
+		/* If this is an EFI GPT disk, msdos should ignore it. */
+		if (SYS_IND(p) == EFI_PMBR_OSTYPE_EFI_GPT) {
+			put_dev_sector(sect);
+			return 0;
+		}
+	}
+	p = (struct partition *) (data + 0x1be);
+#endif
 
 	/*
 	 * Look for partitions in two passes: