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Hermès Bélusca-Maïto
7779fb4459
For fixed-disks (i.e. not floppy nor CD-ROM), check in `disk.c!DiskInitialize()`
whether the disk being enumerated is GPT. If so, retrieve its disk GUID.
Pass this information to `AddReactOSArcDiskInfo()` when filling the ARC
disk information block, which sets the `IsGpt` and `GptSignature` members
of the `ARC_DISK_SIGNATURE` structure accordingly.
Debugging output example, where the first disk (0x80) is MBR, while the
second (0x81) is GPT:
```
(freeldr\disk\disk.c:100) err: DiskInitialize(0x80, 'multi(0)disk(0)rdisk(0)', Type: 25)
(freeldr\disk\disk.c:125) err: Signature: 163fbb9d
(freeldr\disk\disk.c:134) err: Checksum: 47699104
(freeldr\disk\disk.c:137) err: IsPartitionValid: TRUE
(freeldr\disk\disk.c:100) err: DiskInitialize(0x81, 'multi(0)disk(0)rdisk(1)', Type: 25)
(freeldr\disk\disk.c:125) err: Signature: 0
(freeldr\disk\disk.c:134) err: Checksum: 9cb5ff90
(freeldr\disk\disk.c:137) err: IsPartitionValid: TRUE
(freeldr\disk\disk.c:157) err: Disk 0x81 is GPT, DiskGuid: {1e4e8972-e026-4d5f-b213-7be3f2fad3f8}
```
----
This fixes the BSOD 0x7B `INACCESSIBLE_BOOT_DEVICE` that happens when
trying to boot a ReactOS installation present in a partition on a GPT
partitioned disk.
In the kernel IO manager:
`IopCreateArcNamesDisk()`, invoked by `IopCreateArcNames()`, tries to
map the list of disks dynamically detected by the boot disk drivers
with those detected by the bootloader, by matching their disk signatures.
- The signatures of the disks detected by the boot disk drivers are
obtained when querying their drive layout and partition table (which
also tells whether the disk is MBR or GPT partitioned);
- while the signatures of the disks detected by the bootloader are
enumerated in the `LoaderBlock->ArcDiskInformation->DiskSignatureListHead`
linked-list (inside `ARC_DISK_SIGNATURE` structures).
The routine compares the disk signatures by invoking `IopVerifyDiskSignature()`,
which, depending on whether the disk is MBR or GPT (as reported in the
drive layout), compares the signature with that of `ARC_DISK_SIGNATURE`
`Signature` (for MBR) or `GptSignature` (for GPT) structure members.
In case the boot disk turns out to not be mapped -- which was the case
until now if it was GPT-partitioned -- then the `IopMarkBootPartition()`
routine invoked later, wouldn't be able to find and open the boot disk,
and would trigger the BSOD 0x7B, as the result.