[PATCH 1/2] add GPT partition support.

[Dinar valeev]

From: Dinar Valeev <dvaleev at suse.com>

The patch adds GPT partitions support.
It looks for GPT_BASIC_DATA (parted default) and GPT_LINUX_NATIVE gpt
uuids.

Signed-off-by: Dinar Valeev <dvaleev at suse.com>
---
 include/gpt-part.h | 70 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 second/partition.c | 45 +++++++++++++++++++++++++++++++++--
 2 files changed, 113 insertions(+), 2 deletions(-)
 create mode 100644 include/gpt-part.h

diff --git a/include/gpt-part.h b/include/gpt-part.h
new file mode 100644
index 0000000..83b4f77
--- /dev/null
+++ b/include/gpt-part.h
@@ -0,0 +1,70 @@
+/*
+ *  gpt-part.h - Structure of gpt partition table
+ *
+ *  Copyright (C) 2013 Dinar Valeev
+ *
+ *  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.
+ */
+
+#include <byteorder.h>
+
+#define GPT_LINUX_NATIVE \
+((gpt_part_type_t){ cpu_to_le32(0x0FC63DAF), cpu_to_le16(0x8483), cpu_to_le16(0x4772),0x8E, 0x79, \
+	{0x3D, 0x69, 0xD8, 0x47, 0x7D, 0xE4}})
+#define GPT_LINUX_RAID \
+((gpt_part_type_t){ cpu_to_le32(0xa19d880f), cpu_to_le16(0x05fc), cpu_to_le16(0x4d3b), 0xa0, 0x06, \
+	{ 0x74, 0x3f, 0x0f, 0x84, 0x91, 0x1e }})
+#define GPT_BASIC_DATA \
+((gpt_part_type_t){ cpu_to_le32 (0xebd0a0a2), cpu_to_le16 (0xb9e5), cpu_to_le16 (0x4433), 0x87, 0xc0, \
+	{ 0x68, 0xb6, 0xb7, 0x26, 0x99, 0xC7 }})
+
+
+#define GPT_HEADER_SIGNATURE 0x5452415020494645LL
+
+typedef struct
+{
+ u32 data1;
+ u16 data2;
+ u16 data3;
+ u8  data4;
+ u8  data5;
+ u8  data6[6];
+} gpt_part_type_t;
+
+struct gpt_partition {
+	gpt_part_type_t type;           /* Partition type GUID */
+	u8  guid[16];                   /* Unique partition GUID */
+	u64 start;                      /* First partition LBA */
+	u64 end;                        /* End LBA */
+	u64 flags;                      /* Attribute flags */
+	char name[72];                  /* Partition name */
+} __attribute__ ((packed));
+
+struct gpt_header {
+	u64 signature;
+	u32 revision;
+	u32 header_size;
+	u32 header_crc32;
+	u32 reserved;
+	u64 primary;
+	u64 backup;
+	u64 start;
+	u64 end;
+	u8  dguid[16];
+	u64 partitions;
+	u32 maxpart;
+	u32 partentry_size;
+	u32 partentry_crc32;
+} __attribute__ ((packed));
diff --git a/second/partition.c b/second/partition.c
index eb383bc..7facbc4 100644
--- a/second/partition.c
+++ b/second/partition.c
@@ -1,6 +1,8 @@
 /*
  *  partition.c - partition table support
  *
+ *  Copyright (C) 2013 Dinar Valeev
+ *
  *  Copyright (C) 2004 Sven Luther
  *
  *  Copyright (C) 2001, 2002 Ethan Benson
@@ -34,6 +36,7 @@
 #include "mac-part.h"
 #include "fdisk-part.h"
 #include "amiga-part.h"
+#include "gpt-part.h"
 #include "partition.h"
 #include "prom.h"
 #include "string.h"
@@ -184,6 +187,41 @@ partition_fdisk_lookup( const char *dev_name, prom_handle disk,
      }
 }
 
+/* GPT partition format */
+static int gpt_magic_present(unsigned char *block_buffer, unsigned int prom_blksize)
+{
+	struct gpt_header *header = (struct gpt_header *)(block_buffer + prom_blksize);
+	return cpu_to_le64(header->signature) == GPT_HEADER_SIGNATURE;
+}
+
+static inline int
+guid_cmp (gpt_part_type_t left, gpt_part_type_t right)
+{
+	return memcmp(&left, &right, sizeof (gpt_part_type_t));
+}
+
+static void partition_gpt_lookup(prom_handle disk, unsigned int prom_blksize,
+							struct partition_t **list)
+{
+	int partition;
+	struct gpt_header *header = (struct gpt_header *)(block_buffer + prom_blksize);
+
+	if (prom_readblocks(disk, cpu_to_le64(header->partitions), 1, block_buffer) != 1) {
+		prom_printf("Can't read GPT partition table %Lu\n", header->partitions);
+		return;
+	}
+	struct gpt_partition *part = (struct gpt_partition *)(block_buffer);
+
+	for (partition = 1; partition <= cpu_to_le32(header->maxpart); partition++, part++) {
+		if ((!guid_cmp(part->type, GPT_BASIC_DATA))||(!guid_cmp(part->type, GPT_LINUX_NATIVE))||(!guid_cmp(part->type, GPT_LINUX_RAID))) {
+			add_new_partition(list, partition, "Linux", 0, le64_to_cpu(part->start), \
+						cpu_to_le64(part->end) - cpu_to_le64(part->start) + 1, \
+						prom_blksize, 1);
+		}
+	}
+}
+
+
 /* I don't know if it's possible to handle multisession and other multitrack
  * stuffs with the current OF disklabel package. This can still be implemented
  * with direct calls to atapi stuffs.
@@ -357,14 +395,17 @@ partitions_lookup(const char *device)
 	  goto bail;
      }
 
-     /* Read boot blocs */
-     if (prom_readblocks(disk, 0, 1, block_buffer) != 1) {
+     /* Read boot blocks */
+     if (prom_readblocks(disk, 0, 2, block_buffer) != 1) {
 	  prom_printf("Can't read boot blocks\n");
 	  goto bail;
      }
      if (desc->signature == MAC_DRIVER_MAGIC) {
 	  /* pdisk partition format */
 	  partition_mac_lookup(device, disk, prom_blksize, &list);
+     } else if (gpt_magic_present(block_buffer, prom_blksize)) {
+	  /* gpt partition format */
+	  partition_gpt_lookup(disk, prom_blksize, &list);
      } else if ((block_buffer[510] == 0x55) && (block_buffer[511] == 0xaa)) {
 	  /* fdisk partition format */
 	  partition_fdisk_lookup(device, disk, prom_blksize, &list);
-- 
1.8.1.4