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#include <AK/ByteBuffer.h>
#include <Kernel/Devices/GPTPartitionTable.h>
#define GPT_DEBUG
GPTPartitionTable::GPTPartitionTable(DiskDevice& device)
: m_device(move(device))
{
}
GPTPartitionTable::~GPTPartitionTable()
{
}
const GPTPartitionHeader& GPTPartitionTable::header() const
{
return *reinterpret_cast<const GPTPartitionHeader*>(m_cached_header);
}
bool GPTPartitionTable::initialize()
{
if (!m_device->read_block(1, m_cached_header)) {
return false;
}
auto& header = this->header();
#ifdef GPT_DEBUG
kprintf("GPTPartitionTable::initialize: gpt_signature=%#x%x\n", header.sig[1], header.sig[0]);
#endif
if (header.sig[0] != GPT_SIGNATURE && header.sig[1] != GPT_SIGNATURE2) {
kprintf("GPTPartitionTable::initialize: bad GPT signature %#x%x\n", header.sig[1], header.sig[0]);
return false;
}
return true;
}
RefPtr<DiskPartition> GPTPartitionTable::partition(unsigned index)
{
ASSERT(index >= 1 && index <= 4294967294);
auto& header = this->header();
unsigned lba = header.partition_array_start_lba + (((index - 1) * header.partition_entry_size) / BytesPerSector);
if (header.sig[0] != GPT_SIGNATURE) {
kprintf("GPTPartitionTable::initialize: bad gpt signature - not initalized? %#x\n", header.sig);
return nullptr;
}
u8 entries_per_sector = BytesPerSector / header.partition_entry_size;
GPTPartitionEntry entries[entries_per_sector];
this->m_device->read_blocks(lba, 1, (u8*)&entries);
GPTPartitionEntry& entry = entries[((index - 1) % entries_per_sector)];
#ifdef GPT_DEBUG
kprintf("GPTPartitionTable::partition %d\n", index);
kprintf("GPTPartitionTable - offset = %d%d\n", entry.first_lba[1], entry.first_lba[0]);
#endif
if (entry.first_lba[0] == 0x00) {
#ifdef GPT_DEBUG
kprintf("GPTPartitionTable::partition: missing partition requested index=%d\n", index);
#endif
return nullptr;
}
#ifdef GPT_DEBUG
kprintf("GPTPartitionTable::partition: found partition index=%d type=%x-%x-%x-%x\n", index, entry.partition_guid[3], entry.partition_guid[2], entry.partition_guid[1], entry.partition_guid[0]);
#endif
return DiskPartition::create(m_device, entry.first_lba[0], entry.last_lba[0]);
}
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