Checkpoint of better dynamic device support.
This is the first in a series of changes that are designed to
introduce better support for dynamic block devices.
It starts by defining a new Volume object which represents a storage
endpoint that knows how to mount, unmount, and format itself. This
could be a filesystem directly on a partition, or it could be an
emulated FUSE filesystem, an ASEC, or an OBB.
These new volumes can be "stacked" so that unmounting a volume will
also unmount any volumes stacked above it. Volumes that provide
shared storage can also be asked to present themselves (through bind
mounts) into user-specific mount areas.
This change also adds a Disk class which is created based on block
kernel netlink events. Instead of waiting for partition events from
the kernel, it uses gptfdisk to read partition details and creates
the relevant Volume objects.
Change-Id: I0e8bc1f8f9dcb24405f5e795c0658998e22ae2f7
diff --git a/Disk.h b/Disk.h
new file mode 100644
index 0000000..eab8976
--- /dev/null
+++ b/Disk.h
@@ -0,0 +1,92 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_VOLD_DISK_H
+#define ANDROID_VOLD_DISK_H
+
+#include "Utils.h"
+
+#include <utils/Errors.h>
+
+#include <vector>
+
+namespace android {
+namespace vold {
+
+class VolumeBase;
+
+// events:
+// disk_created 127:4
+// disk_meta 127:4 [size] [label]
+// disk_destroyed 127:4
+
+// commands:
+// disk partition_public 127:4
+// disk partition_private 127:4
+// disk partition_mixed 127:4 50
+
+/*
+ * Representation of detected physical media.
+ *
+ * Knows how to create volumes based on the partition tables found, and also
+ * how to repartition itself.
+ */
+class Disk {
+public:
+ Disk(const std::string& eventPath, dev_t device);
+ virtual ~Disk();
+
+ const std::string& getId() { return mId; }
+ const std::string& getSysPath() { return mSysPath; }
+ const std::string& getDevPath() { return mDevPath; }
+ dev_t getDevice() { return mDevice; }
+ uint64_t getSize() { return mSize; }
+ const std::string& getLabel() { return mLabel; }
+
+ std::shared_ptr<VolumeBase> findVolume(const std::string& id);
+
+ status_t readMetadata();
+ status_t readPartitions();
+
+ status_t partitionPublic();
+ status_t partitionPrivate();
+ status_t partitionMixed(int8_t ratio);
+
+private:
+ /* ID that uniquely references this disk */
+ std::string mId;
+ /* Device path under sysfs */
+ std::string mSysPath;
+ /* Device path under dev */
+ std::string mDevPath;
+ /* Kernel device representing disk */
+ dev_t mDevice;
+ /* Size of disk, in bytes */
+ uint64_t mSize;
+ /* User-visible label, such as manufacturer */
+ std::string mLabel;
+ /* Current partitions on disk */
+ std::vector<std::shared_ptr<VolumeBase>> mParts;
+
+ int getMaxMinors();
+
+ DISALLOW_COPY_AND_ASSIGN(Disk);
+};
+
+} // namespace vold
+} // namespace android
+
+#endif