Merge "libdm: Add DeleteDeviceDeferred API" into sc-dev (a35d50c2) · Commits · e / os / android_system_core

fs_mgr/libdm/dm.cpp

+23 −0

Original line number	Diff line number	Diff line
		@@ -35,6 +35,10 @@

		#include "utility.h"

		#ifndef DM_DEFERRED_REMOVE
		#define DM_DEFERRED_REMOVE (1 << 17)
		#endif

		namespace android {
		namespace dm {

		@@ -133,6 +137,25 @@ bool DeviceMapper::DeleteDevice(const std::string& name) {
		return DeleteDevice(name, 0ms);
		}

		bool DeviceMapper::DeleteDeviceDeferred(const std::string& name) {
		struct dm_ioctl io;
		InitIo(&io, name);

		io.flags \|= DM_DEFERRED_REMOVE;
		if (ioctl(fd_, DM_DEV_REMOVE, &io)) {
		PLOG(ERROR) << "DM_DEV_REMOVE with DM_DEFERRED_REMOVE failed for [" << name << "]";
		return false;
		}
		return true;
		}

		bool DeviceMapper::DeleteDeviceIfExistsDeferred(const std::string& name) {
		if (GetState(name) == DmDeviceState::INVALID) {
		return true;
		}
		return DeleteDeviceDeferred(name);
		}

		static std::string GenerateUuid() {
		uuid_t uuid_bytes;
		uuid_generate(uuid_bytes);

fs_mgr/libdm/dm_test.cpp

+62 −0

Original line number	Diff line number	Diff line
		@@ -35,6 +35,7 @@
		#include <libdm/dm.h>
		#include <libdm/loop_control.h>
		#include "test_util.h"
		#include "utility.h"

		using namespace std;
		using namespace std::chrono_literals;
		@@ -617,3 +618,64 @@ TEST(libdm, GetParentBlockDeviceByPath) {
		auto sub_block_device = dm.GetParentBlockDeviceByPath(dev.path());
		ASSERT_EQ(loop.device(), *sub_block_device);
		}

		TEST(libdm, DeleteDeviceDeferredNoReferences) {
		unique_fd tmp(CreateTempFile("file_1", 4096));
		ASSERT_GE(tmp, 0);
		LoopDevice loop(tmp, 10s);
		ASSERT_TRUE(loop.valid());

		DmTable table;
		ASSERT_TRUE(table.Emplace<DmTargetLinear>(0, 1, loop.device(), 0));
		ASSERT_TRUE(table.valid());
		TempDevice dev("libdm-test-dm-linear", table);
		ASSERT_TRUE(dev.valid());

		DeviceMapper& dm = DeviceMapper::Instance();

		std::string path;
		ASSERT_TRUE(dm.GetDmDevicePathByName("libdm-test-dm-linear", &path));
		ASSERT_EQ(0, access(path.c_str(), F_OK));

		ASSERT_TRUE(dm.DeleteDeviceDeferred("libdm-test-dm-linear"));

		ASSERT_TRUE(WaitForFileDeleted(path, 5s));
		ASSERT_EQ(DmDeviceState::INVALID, dm.GetState("libdm-test-dm-linear"));
		ASSERT_NE(0, access(path.c_str(), F_OK));
		ASSERT_EQ(ENOENT, errno);
		}

		TEST(libdm, DeleteDeviceDeferredWaitsForLastReference) {
		unique_fd tmp(CreateTempFile("file_1", 4096));
		ASSERT_GE(tmp, 0);
		LoopDevice loop(tmp, 10s);
		ASSERT_TRUE(loop.valid());

		DmTable table;
		ASSERT_TRUE(table.Emplace<DmTargetLinear>(0, 1, loop.device(), 0));
		ASSERT_TRUE(table.valid());
		TempDevice dev("libdm-test-dm-linear", table);
		ASSERT_TRUE(dev.valid());

		DeviceMapper& dm = DeviceMapper::Instance();

		std::string path;
		ASSERT_TRUE(dm.GetDmDevicePathByName("libdm-test-dm-linear", &path));
		ASSERT_EQ(0, access(path.c_str(), F_OK));

		{
		// Open a reference to block device.
		unique_fd fd(TEMP_FAILURE_RETRY(open(dev.path().c_str(), O_RDONLY \| O_CLOEXEC)));
		ASSERT_GE(fd.get(), 0);

		ASSERT_TRUE(dm.DeleteDeviceDeferred("libdm-test-dm-linear"));

		ASSERT_EQ(0, access(path.c_str(), F_OK));
		}

		// After release device will be removed.
		ASSERT_TRUE(WaitForFileDeleted(path, 5s));
		ASSERT_EQ(DmDeviceState::INVALID, dm.GetState("libdm-test-dm-linear"));
		ASSERT_NE(0, access(path.c_str(), F_OK));
		ASSERT_EQ(ENOENT, errno);
		}

fs_mgr/libdm/include/libdm/dm.h

+6 −0

Original line number	Diff line number	Diff line
		@@ -95,6 +95,12 @@ class DeviceMapper final {
		bool DeleteDevice(const std::string& name, const std::chrono::milliseconds& timeout_ms);
		bool DeleteDeviceIfExists(const std::string& name, const std::chrono::milliseconds& timeout_ms);

		// Enqueues a deletion of device mapper device with the given name once last reference is
		// closed.
		// Returns 'true' on success, false otherwise.
		bool DeleteDeviceDeferred(const std::string& name);
		bool DeleteDeviceIfExistsDeferred(const std::string& name);

		// Fetches and returns the complete state of the underlying device mapper
		// device with given name.
		std::optional<Info> GetDetailedInfo(const std::string& name) const;