Kernel: Introduce a new partitioning subsystem

The partitioning code was very outdated, and required a full refactor.
The new subsystem removes duplicated code and uses more AK containers.

The most important change is that all implementations of the
PartitionTable class conform to one interface, which made it possible
to remove unnecessary code in the EBRPartitionTable class.

Finding partitions is now done in the StorageManagement singleton,
instead of doing so in init.cpp.

Also, now we don't try to find partitions on demand - the kernel will
try to detect if a StorageDevice is partitioned, and if so, will check
what is the partition table, which could be MBR, GUID or EBR.
Then, it will create DiskPartitionMetadata object for each partition
that is available in the partition table. This object will be used
by the partition enumeration code to create a DiskPartition with the
correct minor number.

1 files changed, 42 insertions, 0 deletions

diff --git a/Kernel/Storage/Partition/PartitionTable.cpp b/Kernel/Storage/Partition/PartitionTable.cpp
new file mode 100644
index 0000000000..4f719f872a
--- /dev/null
+++ b/Kernel/Storage/Partition/PartitionTable.cpp
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2020, Liav A. <liavalb@hotmail.co.il>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <Kernel/Storage/Partition/PartitionTable.h>
+
+namespace Kernel {
+PartitionTable::PartitionTable(const StorageDevice& device)
+    : m_device(device)
+{
+}
+
+Optional<DiskPartitionMetadata> PartitionTable::partition(unsigned index)
+{
+    if (index > partitions_count())
+        return {};
+    return m_partitions[index];
+}
+
+}