Merge "libdm: Implement LoadTableAndActivate." (2e98fd23) · Commits · e / os / android_system_core

fs_mgr/libdm/dm.cpp

+31 −2

Original line number	Diff line number	Diff line
		@@ -94,9 +94,38 @@ DmDeviceState DeviceMapper::state(const std::string& /* name */) const {
		return DmDeviceState::INVALID;
		}

		bool DeviceMapper::LoadTableAndActivate(const std::string& /* name /, const DmTable& / table */) {
		bool DeviceMapper::CreateDevice(const std::string& name, const DmTable& table) {
		if (!CreateDevice(name)) {
		return false;
		}
		if (!LoadTableAndActivate(name, table)) {
		DeleteDevice(name);
		return false;
		}
		return true;
		}

		bool DeviceMapper::LoadTableAndActivate(const std::string& name, const DmTable& table) {
		std::string ioctl_buffer(sizeof(struct dm_ioctl), 0);
		ioctl_buffer += table.Serialize();

		struct dm_ioctl* io = reinterpret_cast<struct dm_ioctl*>(&ioctl_buffer[0]);
		InitIo(io, name);
		io->data_size = ioctl_buffer.size();
		io->data_start = sizeof(struct dm_ioctl);
		io->target_count = static_cast<uint32_t>(table.num_targets());
		if (ioctl(fd_, DM_TABLE_LOAD, io)) {
		PLOG(ERROR) << "DM_TABLE_LOAD failed";
		return false;
		}

		InitIo(io, name);
		if (ioctl(fd_, DM_DEV_SUSPEND, io)) {
		PLOG(ERROR) << "DM_TABLE_SUSPEND resume failed";
		return false;
		}
		return true;
		}

		// Reads all the available device mapper targets and their corresponding
		// versions from the kernel and returns in a vector

fs_mgr/libdm/dm_table.cpp

+2 −2

Original line number	Diff line number	Diff line
		@@ -34,8 +34,8 @@ bool DmTable::valid() const {
		return true;
		}

		uint64_t DmTable::size() const {
		return valid() ? size_ : 0;
		uint64_t DmTable::num_sectors() const {
		return valid() ? num_sectors_ : 0;
		}

		// Returns a string represnetation of the table that is ready to be passed

fs_mgr/libdm/include/libdm/dm.h

+14 −11

Original line number	Diff line number	Diff line
		@@ -69,14 +69,6 @@ class DeviceMapper final {
		uint64_t dev_;
		};

		// Creates a device mapper device with given name.
		// Return 'true' on success and 'false' on failure to
		// create OR if a device mapper device with the same name already
		// exists.
		// TODO(b/110035986): Make this method private and to be only
		// called through LoadTableAndActivate() below.
		bool CreateDevice(const std::string& name);

		// Removes a device mapper device with the given name.
		// Returns 'true' on success, false otherwise.
		bool DeleteDevice(const std::string& name);
		@@ -90,9 +82,14 @@ class DeviceMapper final {
		// One of INVALID, SUSPENDED or ACTIVE.
		DmDeviceState state(const std::string& name) const;

		// Loads the device mapper table from parameter into the underlying
		// device mapper device with given name and activate / resumes the device in the process.
		// If a device mapper device with the 'name', doesn't exist, it will be created.
		// Creates a device, loads the given table, and activates it. If the device
		// is not able to be activated, it is destroyed, and false is returned.
		bool CreateDevice(const std::string& name, const DmTable& table);

		// Loads the device mapper table from parameter into the underlying device
		// mapper device with given name and activate / resumes the device in the
		// process. A device with the given name must already exist.
		//
		// Returns 'true' on success, false otherwise.
		bool LoadTableAndActivate(const std::string& name, const DmTable& table);

		@@ -140,6 +137,12 @@ class DeviceMapper final {
		}
		}

		// Creates a device mapper device with given name.
		// Return 'true' on success and 'false' on failure to
		// create OR if a device mapper device with the same name already
		// exists.
		bool CreateDevice(const std::string& name);

		int fd_;
		// Non-copyable & Non-movable
		DeviceMapper(const DeviceMapper&) = delete;

fs_mgr/libdm/include/libdm/dm_table.h

+6 −3

Original line number	Diff line number	Diff line
		@@ -30,7 +30,7 @@ namespace dm {

		class DmTable {
		public:
		DmTable() : size_(0){};
		DmTable() : num_sectors_(0){};

		// Adds a target to the device mapper table for a range specified in the target object.
		// The function will return 'true' if the target was successfully added and doesn't overlap with
		@@ -48,9 +48,12 @@ class DmTable {
		// table is malformed.
		bool valid() const;

		// Returns the toatl number of targets.
		size_t num_targets() const { return targets_.size(); }

		// Returns the total size represented by the table in terms of number of 512-byte sectors.
		// NOTE: This function will overlook if there are any gaps in the targets added in the table.
		uint64_t size() const;
		uint64_t num_sectors() const;

		// Returns the string represntation of the table that is ready to be passed into the kernel
		// as part of the DM_TABLE_LOAD ioctl.
		@@ -66,7 +69,7 @@ class DmTable {

		// Total size in terms of # of sectors, as calculated by looking at the last and the first
		// target in 'target_'.
		uint64_t size_;
		uint64_t num_sectors_;
		};

		} // namespace dm

fs_mgr/tools/dmctl.cpp

+4 −1

Original line number	Diff line number	Diff line
		@@ -34,6 +34,7 @@
		#include <vector>

		using DeviceMapper = ::android::dm::DeviceMapper;
		using DmTable = ::android::dm::DmTable;
		using DmTarget = ::android::dm::DmTarget;
		using DmBlockDevice = ::android::dm::DeviceMapper::DmBlockDevice;

		@@ -53,9 +54,11 @@ static int DmCreateCmdHandler(int argc, char** argv) {
		return -EINVAL;
		}

		DmTable table;

		std::string name = argv[0];
		DeviceMapper& dm = DeviceMapper::Instance();
		if (!dm.CreateDevice(name)) {
		if (!dm.CreateDevice(name, table)) {
		std::cerr << "Failed to create device-mapper device with name: " << name << std::endl;
		return -EIO;
		}