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Adding hybrid GPT patch
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Carl Fürstenberg committed Mar 8, 2012
1 parent bd76f9d commit 93ffba6
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346 changes: 346 additions & 0 deletions debian/patches/0001-Hybrid-GPT-msdos-support.patch
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@@ -0,0 +1,346 @@
From: =?UTF-8?q?Carl=20F=C3=BCrstenberg?= <carl@excito.com>
Date: Thu, 8 Mar 2012 16:26:37 +0100
Subject: Hybrid GPT/msdos support

---
libparted/labels/gpt.c | 241 +++++++++++++++++++++++++++++++++++++++++++++++-
1 files changed, 236 insertions(+), 5 deletions(-)

diff --git a/libparted/labels/gpt.c b/libparted/labels/gpt.c
index 84bdc12..24b0921 100644
--- a/libparted/labels/gpt.c
+++ b/libparted/labels/gpt.c
@@ -286,6 +286,7 @@ typedef struct _GPTPartitionData
} GPTPartitionData;

static PedDiskType gpt_disk_type;
+static PedDiskType gpt_sync_mbr_disk_type;

static inline uint32_t
pth_get_size (const PedDevice *dev)
@@ -454,8 +455,50 @@ _pmbr_is_valid (const LegacyMBR_t *mbr)
return 0;
}

+/* checks if device has a hybrid protective MBR partition table
+ *
+ * If the 1st partition has type 0xEE that spans the entire
+ * size of the disk from sector 1 to the last sector
+ * (or 2 TiB, whichever is smaller), we consider it 'normal' GPT.
+ * Otherwise it is synced GPT with hybridized pMBR.
+ */
+static inline int
+_has_hybrid_pmbr (const PedDevice *dev)
+{
+ int has_hybrid_pmbr = 1;
+
+ PED_ASSERT (dev != NULL);
+
+ void *label;
+ if (!ptt_read_sector (dev, 0, &label))
+ return 0;
+
+ LegacyMBR_t mbr;
+ memcpy(&mbr, label, sizeof(mbr));
+
+ if (mbr.Signature != PED_CPU_TO_LE16 (MSDOS_MBR_SIGNATURE)) {
+ free(label);
+ return 0;
+ }
+
+ uint32_t efi_gpt_expected_size;
+ if ((dev->length - 1ULL) > 0xFFFFFFFFULL)
+ efi_gpt_expected_size = 0xFFFFFFFF;
+ else
+ efi_gpt_expected_size = dev->length - 1UL;
+
+ if ((mbr.PartitionRecord[0].OSType == EFI_PMBR_OSTYPE_EFI) &&
+ (mbr.PartitionRecord[0].StartingLBA == PED_CPU_TO_LE32(1)) &&
+ (mbr.PartitionRecord[0].SizeInLBA == PED_CPU_TO_LE32(efi_gpt_expected_size)))
+ /* pMBR is not hybrid */
+ has_hybrid_pmbr = 0;
+
+ free(label);
+ return has_hybrid_pmbr;
+}
+
static int
-gpt_probe (const PedDevice *dev)
+_gpt_probe_generic(const PedDevice *dev)
{
GuidPartitionTableHeader_t *gpt = NULL;
int gpt_sig_found = 0;
@@ -508,6 +551,19 @@ gpt_probe (const PedDevice *dev)
return ok;
}

+static int
+gpt_probe (const PedDevice *dev)
+{
+ return _gpt_probe_generic(dev) && !_has_hybrid_pmbr(dev);
+}
+
+
+static int
+gpt_sync_mbr_probe (const PedDevice *dev)
+{
+ return _gpt_probe_generic(dev) && _has_hybrid_pmbr(dev);
+}
+
static PedDisk *
gpt_alloc (const PedDevice *dev)
{
@@ -546,6 +602,36 @@ error:
}

static PedDisk *
+gpt_sync_mbr_alloc (const PedDevice *dev)
+{
+ PedDisk *disk;
+ GPTDiskData *gpt_disk_data;
+ PedSector data_start, data_end;
+
+ disk = _ped_disk_alloc ((PedDevice *) dev, &gpt_sync_mbr_disk_type);
+ if (!disk)
+ goto error;
+ disk->disk_specific = gpt_disk_data = ped_malloc (sizeof (GPTDiskData));
+ if (!disk->disk_specific)
+ goto error_free_disk;
+
+ data_start = 2 + GPT_DEFAULT_PARTITION_ENTRY_ARRAY_SIZE / dev->sector_size;
+ data_end = dev->length - 2
+ - GPT_DEFAULT_PARTITION_ENTRY_ARRAY_SIZE / dev->sector_size;
+ ped_geometry_init (&gpt_disk_data->data_area, dev, data_start,
+ data_end - data_start + 1);
+ gpt_disk_data->entry_count = GPT_DEFAULT_PARTITION_ENTRIES;
+ uuid_generate ((unsigned char *) &gpt_disk_data->uuid);
+ swap_uuid_and_efi_guid ((unsigned char *) (&gpt_disk_data->uuid));
+ return disk;
+
+error_free_disk:
+ free (disk);
+error:
+ return NULL;
+}
+
+static PedDisk *
gpt_duplicate (const PedDisk *disk)
{
PedDisk *new_disk;
@@ -930,7 +1016,7 @@ gpt_read (PedDisk *disk)

/* motivation: let the user decide about the pmbr... during
ped_disk_probe(), they probably didn't get a choice... */
- if (!gpt_probe (disk->dev))
+ if (!gpt_probe (disk->dev) && !gpt_sync_mbr_probe(disk->dev))
goto error;

GuidPartitionTableHeader_t *gpt = NULL;
@@ -1087,11 +1173,59 @@ error:
return 0;
}

+
+static inline unsigned char
+_part_to_ostype (PedPartition* part)
+{
+ if (part->fs_type) {
+ if (strncmp (part->fs_type->name, "fat", 3) == 0) return 0xc;
+ if (strncmp (part->fs_type->name, "ntfs", 4) == 0) return 0x7;
+ if (strncmp (part->fs_type->name, "hfs", 3) == 0) return 0xaf;
+ if (strstr (part->fs_type->name, "swap")) return 0x82;
+ }
+ return 0x83; // Everything else is Linux
+}
+
+static inline PedPartition*
+_find_first_part (const PedDisk* disk)
+{
+ PedPartition *retval = NULL, *part = NULL;
+ uint64_t lowest_end = 0xffffffffffffffff;
+ while (part = ped_disk_next_partition (disk, part)) {
+ if (part->geom.start == 0 || part->type == PED_PARTITION_METADATA
+ || part->type == PED_PARTITION_FREESPACE)
+ continue;
+ if (part->geom.end < lowest_end) {
+ retval = part;
+ lowest_end = part->geom.end;
+ }
+ }
+ return retval;
+}
+
+static inline uint32_t
+_part_32bitmax (uint64_t in)
+{
+ if (in > 0xFFFFFFFFULL)
+ return 0xFFFFFFFF;
+ else
+ return (uint32_t)in;
+}
+
+
#ifndef DISCOVER_ONLY
/* Write the protective MBR (to keep DOS happy) */
static int
-_write_pmbr (PedDevice *dev, bool pmbr_boot)
+_write_pmbr (const PedDisk *disk, bool pmbr_boot)
{
+ PedDevice * dev = disk->dev;
+
+ /* need sync GPT -> hybrid pMBR ? */
+ int sync_pmbr = !strcmp(disk->type->name, "gpt_sync_mbr") ? 1 : 0;
+
+ int i, pmbr_id, first_entry = 0, last_entry = 3;
+ PedPartition *part = NULL, *esp;
+
/* The UEFI spec is not clear about what to do with the following
elements of the Protective MBR (pmbr): BootCode (0-440B),
UniqueMBRSignature (440B-444B) and Unknown (444B-446B).
@@ -1105,6 +1239,8 @@ _write_pmbr (PedDevice *dev, bool pmbr_boot)
memset (pmbr->PartitionRecord, 0, sizeof pmbr->PartitionRecord);

pmbr->Signature = PED_CPU_TO_LE16 (MSDOS_MBR_SIGNATURE);
+
+ if (!sync_pmbr) {
pmbr->PartitionRecord[0].OSType = EFI_PMBR_OSTYPE_EFI;
pmbr->PartitionRecord[0].StartSector = 1;
pmbr->PartitionRecord[0].EndHead = 0xFE;
@@ -1117,7 +1253,60 @@ _write_pmbr (PedDevice *dev, bool pmbr_boot)
pmbr->PartitionRecord[0].SizeInLBA = PED_CPU_TO_LE32 (dev->length - 1UL);
if (pmbr_boot)
pmbr->PartitionRecord[0].BootIndicator = 0x80;
-
+ } else {
+ /* Search for an EFI System Partition */
+ esp = _find_first_part(disk);
+ if (!esp || !esp->fs_type || strncmp (esp->fs_type->name, "fat", 3) != 0)
+ esp = NULL;
+
+ pmbr_id = 3;
+ if (esp) {
+ pmbr_id = 0;
+ first_entry = 1;
+ last_entry = 4;
+ }
+
+ /* Write a pseudo-PMBR so Linux is happy */
+ pmbr->PartitionRecord[pmbr_id].OSType = EFI_PMBR_OSTYPE_EFI;
+ pmbr->PartitionRecord[pmbr_id].StartSector = 1;
+ pmbr->PartitionRecord[pmbr_id].EndHead = 0xFE;
+ pmbr->PartitionRecord[pmbr_id].EndSector = 0xFF;
+ pmbr->PartitionRecord[pmbr_id].EndTrack = 0xFF;
+ pmbr->PartitionRecord[pmbr_id].StartingLBA = PED_CPU_TO_LE32(1);
+ pmbr->PartitionRecord[pmbr_id].SizeInLBA = 1;
+ if (esp)
+ pmbr->PartitionRecord[pmbr_id].SizeInLBA = esp->geom.end - 1;
+
+ /* sync the first 3 GPT entries to MBR primary partitions */
+ for (i=first_entry; i < last_entry; i++) {
+ part = ped_disk_next_partition (disk, part);
+ if (part == NULL)
+ break;
+ /* we might get a starting garbage partition */
+ if (part->geom.start == 0 || part->type == PED_PARTITION_METADATA || part->type == PED_PARTITION_FREESPACE || part == esp) {
+ i--;
+ continue;
+ }
+
+ /* partition can not be represented by dos label - don't sync it */
+ if (part->geom.start > 0xFFFFFFFF ||
+ (part->geom.end - part->geom.start + 1) > 0xFFFFFFFF) {
+ continue;
+ }
+
+ pmbr->PartitionRecord[i].OSType = _part_to_ostype(part);
+ pmbr->PartitionRecord[i].StartHead = 0xFE;
+ pmbr->PartitionRecord[i].StartSector = 0xFF;
+ pmbr->PartitionRecord[i].StartTrack = 0xFF;
+ pmbr->PartitionRecord[i].EndHead = 0xFE;
+ pmbr->PartitionRecord[i].EndSector = 0xFF;
+ pmbr->PartitionRecord[i].EndTrack = 0xFF;
+ pmbr->PartitionRecord[i].StartingLBA = _part_32bitmax(part->geom.start);
+ if(((GPTPartitionData*)part->disk_specific)->boot)
+ pmbr->PartitionRecord[i].BootIndicator = 0x80;
+ pmbr->PartitionRecord[i].SizeInLBA = _part_32bitmax(part->geom.end - part->geom.start + 1);
+ }
+ }
int write_ok = ped_device_write (dev, pmbr, GPT_PMBR_LBA,
GPT_PMBR_SECTORS);
free (s0);
@@ -1237,7 +1426,7 @@ gpt_write (const PedDisk *disk)
ptes_crc = efi_crc32 (ptes, ptes_bytes);

/* Write protective MBR */
- if (!_write_pmbr (disk->dev, gpt_disk_data->pmbr_boot))
+ if (!_write_pmbr (disk, gpt_disk_data->pmbr_boot))
goto error_free_ptes;

/* Write PTH and PTEs */
@@ -1857,6 +2046,38 @@ static PedDiskOps gpt_disk_ops =
PT_op_function_initializers (gpt)
};

+static PedDiskOps gpt_sync_mbr_disk_ops =
+{
+ clobber: NULL,
+ write: NULL_IF_DISCOVER_ONLY (gpt_write),
+
+ partition_set_name: gpt_partition_set_name,
+ partition_get_name: gpt_partition_get_name,
+
+ /* probe function redefined */
+ probe: gpt_sync_mbr_probe,
+ /* alloc function redefined */
+ alloc: gpt_sync_mbr_alloc,
+ duplicate: gpt_duplicate,
+ free: gpt_free,
+ read: gpt_read,
+ partition_new: gpt_partition_new,
+ partition_duplicate: gpt_partition_duplicate,
+ partition_set_flag: gpt_partition_set_flag,
+ partition_get_flag: gpt_partition_get_flag,
+ partition_set_system: gpt_partition_set_system,
+ partition_is_flag_available: gpt_partition_is_flag_available,
+ partition_align: gpt_partition_align,
+ partition_destroy: gpt_partition_destroy,
+ partition_enumerate: gpt_partition_enumerate,
+ alloc_metadata: gpt_alloc_metadata,
+ get_max_primary_partition_count: gpt_get_max_primary_partition_count,
+ get_max_supported_partition_count: gpt_get_max_supported_partition_count,
+ partition_check: gpt_partition_check,
+ max_length: gpt_partition_max_length,
+ max_start_sector: gpt_partition_max_start_sector
+};
+
static PedDiskType gpt_disk_type =
{
next: NULL,
@@ -1865,16 +2086,26 @@ static PedDiskType gpt_disk_type =
features: PED_DISK_TYPE_PARTITION_NAME
};

+static PedDiskType gpt_sync_mbr_disk_type =
+{
+ next: NULL,
+ name: "gpt_sync_mbr",
+ ops: &gpt_sync_mbr_disk_ops,
+ features: PED_DISK_TYPE_PARTITION_NAME
+};
+
void
ped_disk_gpt_init ()
{
ped_disk_type_register (&gpt_disk_type);
+ ped_disk_type_register (&gpt_sync_mbr_disk_type);
}

void
ped_disk_gpt_done ()
{
ped_disk_type_unregister (&gpt_disk_type);
+ ped_disk_type_unregister (&gpt_sync_mbr_disk_type);
}

verify (sizeof (GuidPartitionEntryAttributes_t) == 8);
--
1 change: 1 addition & 0 deletions debian/patches/series
View file
@@ -0,0 +1 @@
0001-Hybrid-GPT-msdos-support.patch

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