123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709 |
- package devmapper
- /*
- #cgo LDFLAGS: -L. -ldevmapper
- #include <stdio.h>
- #include <stdlib.h>
- #include <unistd.h>
- #include <libdevmapper.h>
- #include <linux/loop.h>
- #include <sys/types.h>
- #include <sys/stat.h>
- #include <fcntl.h>
- #include <sys/ioctl.h>
- #include <linux/fs.h>
- #include <errno.h>
- #ifndef LOOP_CTL_GET_FREE
- #define LOOP_CTL_GET_FREE 0x4C82
- #endif
- // FIXME: this could easily be rewritten in go
- char* attach_loop_device(const char *filename, int *loop_fd_out)
- {
- struct loop_info64 loopinfo = {0};
- struct stat st;
- char buf[64];
- int i, loop_fd, fd, start_index;
- char* loopname;
- *loop_fd_out = -1;
- start_index = 0;
- fd = open("/dev/loop-control", O_RDONLY);
- if (fd >= 0) {
- start_index = ioctl(fd, LOOP_CTL_GET_FREE);
- close(fd);
- if (start_index < 0)
- start_index = 0;
- }
- fd = open(filename, O_RDWR);
- if (fd < 0) {
- perror("open");
- return NULL;
- }
- loop_fd = -1;
- for (i = start_index ; loop_fd < 0 ; i++ ) {
- if (sprintf(buf, "/dev/loop%d", i) < 0) {
- close(fd);
- return NULL;
- }
- if (stat(buf, &st)) {
- if (!S_ISBLK(st.st_mode)) {
- fprintf(stderr, "[error] Loopback device %s is not a block device.\n", buf);
- } else if (errno == ENOENT) {
- fprintf(stderr, "[error] There are no more loopback device available.\n");
- } else {
- fprintf(stderr, "[error] Unkown error trying to stat the loopback device %s (errno: %d).\n", buf, errno);
- }
- close(fd);
- return NULL;
- }
- loop_fd = open(buf, O_RDWR);
- if (loop_fd < 0 && errno == ENOENT) {
- fprintf(stderr, "[error] The loopback device %s does not exists.\n", buf);
- close(fd);
- return NULL;
- } else if (loop_fd < 0) {
- fprintf(stderr, "[error] Unkown error openning the loopback device %s. (errno: %d)\n", buf, errno);
- continue;
- }
- if (ioctl(loop_fd, LOOP_SET_FD, (void *)(size_t)fd) < 0) {
- int errsv = errno;
- close(loop_fd);
- loop_fd = -1;
- if (errsv != EBUSY) {
- close(fd);
- fprintf(stderr, "cannot set up loopback device %s: %s", buf, strerror(errsv));
- return NULL;
- }
- continue;
- }
- close(fd);
- strncpy((char*)loopinfo.lo_file_name, buf, LO_NAME_SIZE);
- loopinfo.lo_offset = 0;
- loopinfo.lo_flags = LO_FLAGS_AUTOCLEAR;
- if (ioctl(loop_fd, LOOP_SET_STATUS64, &loopinfo) < 0) {
- perror("ioctl LOOP_SET_STATUS64");
- if (ioctl(loop_fd, LOOP_CLR_FD, 0) < 0) {
- perror("ioctl LOOP_CLR_FD");
- }
- close(loop_fd);
- fprintf (stderr, "cannot set up loopback device info");
- return (NULL);
- }
- loopname = strdup(buf);
- if (loopname == NULL) {
- close(loop_fd);
- return (NULL);
- }
- *loop_fd_out = loop_fd;
- return (loopname);
- }
- return (NULL);
- }
- static int64_t get_block_size(int fd)
- {
- uint64_t size;
- if (ioctl(fd, BLKGETSIZE64, &size) == -1)
- return -1;
- return ((int64_t)size);
- }
- extern void DevmapperLogCallback(int level, char *file, int line, int dm_errno_or_class, char *str);
- static void
- log_cb(int level, const char *file, int line,
- int dm_errno_or_class, const char *f, ...)
- {
- char buffer[256];
- va_list ap;
- va_start(ap, f);
- vsnprintf(buffer, 256, f, ap);
- va_end(ap);
- DevmapperLogCallback(level, (char *)file, line, dm_errno_or_class, buffer);
- }
- static void
- log_with_errno_init ()
- {
- dm_log_with_errno_init(log_cb);
- }
- */
- import "C"
- import (
- "errors"
- "fmt"
- "github.com/dotcloud/docker/utils"
- "os"
- "runtime"
- "syscall"
- "unsafe"
- )
- type DevmapperLogger interface {
- log(level int, file string, line int, dmError int, message string)
- }
- const (
- DeviceCreate TaskType = iota
- DeviceReload
- DeviceRemove
- DeviceRemoveAll
- DeviceSuspend
- DeviceResume
- DeviceInfo
- DeviceDeps
- DeviceRename
- DeviceVersion
- DeviceStatus
- DeviceTable
- DeviceWaitevent
- DeviceList
- DeviceClear
- DeviceMknodes
- DeviceListVersions
- DeviceTargetMsg
- DeviceSetGeometry
- )
- const (
- AddNodeOnResume AddNodeType = iota
- AddNodeOnCreate
- )
- var (
- ErrTaskRun = errors.New("dm_task_run failed")
- ErrTaskSetName = errors.New("dm_task_set_name failed")
- ErrTaskSetMessage = errors.New("dm_task_set_message failed")
- ErrTaskSetAddNode = errors.New("dm_task_set_add_node failed")
- ErrTaskSetRO = errors.New("dm_task_set_ro failed")
- ErrTaskAddTarget = errors.New("dm_task_add_target failed")
- ErrGetDriverVersion = errors.New("dm_task_get_driver_version failed")
- ErrAttachLoopbackDevice = errors.New("loopback mounting failed")
- ErrGetBlockSize = errors.New("Can't get block size")
- ErrUdevWait = errors.New("wait on udev cookie failed")
- ErrSetDevDir = errors.New("dm_set_dev_dir failed")
- ErrGetLibraryVersion = errors.New("dm_get_library_version failed")
- ErrCreateRemoveTask = errors.New("Can't create task of type DeviceRemove")
- ErrRunRemoveDevice = errors.New("running removeDevice failed")
- )
- type (
- Task struct {
- unmanaged *C.struct_dm_task
- }
- Info struct {
- Exists int
- Suspended int
- LiveTable int
- InactiveTable int
- OpenCount int32
- EventNr uint32
- Major uint32
- Minor uint32
- ReadOnly int
- TargetCount int32
- }
- TaskType int
- AddNodeType int
- )
- func (t *Task) destroy() {
- if t != nil {
- C.dm_task_destroy(t.unmanaged)
- runtime.SetFinalizer(t, nil)
- }
- }
- func TaskCreate(tasktype TaskType) *Task {
- c_task := C.dm_task_create(C.int(tasktype))
- if c_task == nil {
- return nil
- }
- task := &Task{unmanaged: c_task}
- runtime.SetFinalizer(task, (*Task).destroy)
- return task
- }
- func (t *Task) Run() error {
- if res := C.dm_task_run(t.unmanaged); res != 1 {
- return ErrTaskRun
- }
- return nil
- }
- func (t *Task) SetName(name string) error {
- c_name := C.CString(name)
- defer free(c_name)
- if res := C.dm_task_set_name(t.unmanaged, c_name); res != 1 {
- return ErrTaskSetName
- }
- return nil
- }
- func (t *Task) SetMessage(message string) error {
- c_message := C.CString(message)
- defer free(c_message)
- if res := C.dm_task_set_message(t.unmanaged, c_message); res != 1 {
- return ErrTaskSetMessage
- }
- return nil
- }
- func (t *Task) SetSector(sector uint64) error {
- if res := C.dm_task_set_sector(t.unmanaged, C.uint64_t(sector)); res != 1 {
- return ErrTaskSetAddNode
- }
- return nil
- }
- func (t *Task) SetCookie(cookie *uint32, flags uint16) error {
- c_cookie := C.uint32_t(*cookie)
- if res := C.dm_task_set_cookie(t.unmanaged, &c_cookie, C.uint16_t(flags)); res != 1 {
- return ErrTaskSetAddNode
- }
- *cookie = uint32(c_cookie)
- return nil
- }
- func (t *Task) SetAddNode(add_node AddNodeType) error {
- if res := C.dm_task_set_add_node(t.unmanaged, C.dm_add_node_t(add_node)); res != 1 {
- return ErrTaskSetAddNode
- }
- return nil
- }
- func (t *Task) SetRo() error {
- if res := C.dm_task_set_ro(t.unmanaged); res != 1 {
- return ErrTaskSetRO
- }
- return nil
- }
- func (t *Task) AddTarget(start uint64, size uint64, ttype string, params string) error {
- c_ttype := C.CString(ttype)
- defer free(c_ttype)
- c_params := C.CString(params)
- defer free(c_params)
- if res := C.dm_task_add_target(t.unmanaged, C.uint64_t(start), C.uint64_t(size), c_ttype, c_params); res != 1 {
- return ErrTaskAddTarget
- }
- return nil
- }
- func (t *Task) GetDriverVersion() (string, error) {
- buffer := C.CString(string(make([]byte, 128)))
- defer free(buffer)
- if res := C.dm_task_get_driver_version(t.unmanaged, buffer, 128); res != 1 {
- return "", ErrGetDriverVersion
- }
- return C.GoString(buffer), nil
- }
- func (t *Task) GetInfo() (*Info, error) {
- c_info := C.struct_dm_info{}
- if res := C.dm_task_get_info(t.unmanaged, &c_info); res != 1 {
- return nil, ErrGetDriverVersion
- }
- return &Info{
- Exists: int(c_info.exists),
- Suspended: int(c_info.suspended),
- LiveTable: int(c_info.live_table),
- InactiveTable: int(c_info.inactive_table),
- OpenCount: int32(c_info.open_count),
- EventNr: uint32(c_info.event_nr),
- Major: uint32(c_info.major),
- Minor: uint32(c_info.minor),
- ReadOnly: int(c_info.read_only),
- TargetCount: int32(c_info.target_count),
- }, nil
- }
- func (t *Task) GetNextTarget(next uintptr) (uintptr, uint64, uint64, string, string) {
- var (
- c_start, c_length C.uint64_t
- c_target_type, c_params *C.char
- )
- nextp := C.dm_get_next_target(t.unmanaged, unsafe.Pointer(next), &c_start, &c_length, &c_target_type, &c_params)
- return uintptr(nextp), uint64(c_start), uint64(c_length), C.GoString(c_target_type), C.GoString(c_params)
- }
- func AttachLoopDevice(filename string) (*os.File, error) {
- c_filename := C.CString(filename)
- defer free(c_filename)
- var fd C.int
- res := C.attach_loop_device(c_filename, &fd)
- if res == nil {
- if os.Getenv("DEBUG") != "" {
- C.perror(C.CString(fmt.Sprintf("[debug] Error attach_loop_device(%s, %d)", filename, int(fd))))
- }
- return nil, ErrAttachLoopbackDevice
- }
- defer free(res)
- return os.NewFile(uintptr(fd), C.GoString(res)), nil
- }
- func getBlockSize(fd uintptr) int {
- var size uint64
- if _, _, err := syscall.Syscall(syscall.SYS_IOCTL, fd, C.BLKGETSIZE64, uintptr(unsafe.Pointer(&size))); err != 0 {
- utils.Debugf("Error ioctl: %s", err)
- return -1
- }
- return int(size)
- }
- func GetBlockDeviceSize(file *os.File) (uint64, error) {
- if size := C.get_block_size(C.int(file.Fd())); size == -1 {
- return 0, ErrGetBlockSize
- } else {
- return uint64(size), nil
- }
- }
- func UdevWait(cookie uint32) error {
- if res := C.dm_udev_wait(C.uint32_t(cookie)); res != 1 {
- utils.Debugf("Failed to wait on udev cookie %d", cookie)
- return ErrUdevWait
- }
- return nil
- }
- func LogInitVerbose(level int) {
- C.dm_log_init_verbose(C.int(level))
- }
- var dmLogger DevmapperLogger = nil
- func logInit(logger DevmapperLogger) {
- dmLogger = logger
- C.log_with_errno_init()
- }
- func SetDevDir(dir string) error {
- c_dir := C.CString(dir)
- defer free(c_dir)
- if res := C.dm_set_dev_dir(c_dir); res != 1 {
- utils.Debugf("Error dm_set_dev_dir")
- return ErrSetDevDir
- }
- return nil
- }
- func GetLibraryVersion() (string, error) {
- buffer := C.CString(string(make([]byte, 128)))
- defer free(buffer)
- if res := C.dm_get_library_version(buffer, 128); res != 1 {
- return "", ErrGetLibraryVersion
- }
- return C.GoString(buffer), nil
- }
- // Useful helper for cleanup
- func RemoveDevice(name string) error {
- task := TaskCreate(DeviceRemove)
- if task == nil {
- return ErrCreateRemoveTask
- }
- if err := task.SetName(name); err != nil {
- utils.Debugf("Can't set task name %s", name)
- return err
- }
- if err := task.Run(); err != nil {
- return ErrRunRemoveDevice
- }
- return nil
- }
- func free(p *C.char) {
- C.free(unsafe.Pointer(p))
- }
- // This is the programmatic example of "dmsetup create"
- func createPool(poolName string, dataFile *os.File, metadataFile *os.File) error {
- task, err := createTask(DeviceCreate, poolName)
- if task == nil {
- return err
- }
- size, err := GetBlockDeviceSize(dataFile)
- if err != nil {
- return fmt.Errorf("Can't get data size")
- }
- params := metadataFile.Name() + " " + dataFile.Name() + " 128 32768"
- if err := task.AddTarget(0, size/512, "thin-pool", params); err != nil {
- return fmt.Errorf("Can't add target")
- }
- var cookie uint32 = 0
- if err := task.SetCookie(&cookie, 0); err != nil {
- return fmt.Errorf("Can't set cookie")
- }
- if err := task.Run(); err != nil {
- return fmt.Errorf("Error running DeviceCreate")
- }
- UdevWait(cookie)
- return nil
- }
- func createTask(t TaskType, name string) (*Task, error) {
- task := TaskCreate(t)
- if task == nil {
- return nil, fmt.Errorf("Can't create task of type %d", int(t))
- }
- if err := task.SetName(name); err != nil {
- return nil, fmt.Errorf("Can't set task name %s", name)
- }
- return task, nil
- }
- func getInfo(name string) (*Info, error) {
- task, err := createTask(DeviceInfo, name)
- if task == nil {
- return nil, err
- }
- if err := task.Run(); err != nil {
- return nil, err
- }
- return task.GetInfo()
- }
- func getStatus(name string) (uint64, uint64, string, string, error) {
- task, err := createTask(DeviceStatus, name)
- if task == nil {
- utils.Debugf("getStatus: Error createTask: %s", err)
- return 0, 0, "", "", err
- }
- if err := task.Run(); err != nil {
- utils.Debugf("getStatus: Error Run: %s", err)
- return 0, 0, "", "", err
- }
- devinfo, err := task.GetInfo()
- if err != nil {
- utils.Debugf("getStatus: Error GetInfo: %s", err)
- return 0, 0, "", "", err
- }
- if devinfo.Exists == 0 {
- utils.Debugf("getStatus: Non existing device %s", name)
- return 0, 0, "", "", fmt.Errorf("Non existing device %s", name)
- }
- _, start, length, target_type, params := task.GetNextTarget(0)
- return start, length, target_type, params, nil
- }
- func setTransactionId(poolName string, oldId uint64, newId uint64) error {
- task, err := createTask(DeviceTargetMsg, poolName)
- if task == nil {
- return err
- }
- if err := task.SetSector(0); err != nil {
- return fmt.Errorf("Can't set sector")
- }
- if err := task.SetMessage(fmt.Sprintf("set_transaction_id %d %d", oldId, newId)); err != nil {
- return fmt.Errorf("Can't set message")
- }
- if err := task.Run(); err != nil {
- return fmt.Errorf("Error running setTransactionId")
- }
- return nil
- }
- func suspendDevice(name string) error {
- task, err := createTask(DeviceSuspend, name)
- if task == nil {
- return err
- }
- if err := task.Run(); err != nil {
- return fmt.Errorf("Error running DeviceSuspend")
- }
- return nil
- }
- func resumeDevice(name string) error {
- task, err := createTask(DeviceResume, name)
- if task == nil {
- return err
- }
- var cookie uint32 = 0
- if err := task.SetCookie(&cookie, 0); err != nil {
- return fmt.Errorf("Can't set cookie")
- }
- if err := task.Run(); err != nil {
- return fmt.Errorf("Error running DeviceSuspend")
- }
- UdevWait(cookie)
- return nil
- }
- func createDevice(poolName string, deviceId int) error {
- utils.Debugf("[devmapper] createDevice(poolName=%v, deviceId=%v)", poolName, deviceId)
- task, err := createTask(DeviceTargetMsg, poolName)
- if task == nil {
- return err
- }
- if err := task.SetSector(0); err != nil {
- return fmt.Errorf("Can't set sector")
- }
- if err := task.SetMessage(fmt.Sprintf("create_thin %d", deviceId)); err != nil {
- return fmt.Errorf("Can't set message")
- }
- if err := task.Run(); err != nil {
- return fmt.Errorf("Error running createDevice")
- }
- return nil
- }
- func deleteDevice(poolName string, deviceId int) error {
- task, err := createTask(DeviceTargetMsg, poolName)
- if task == nil {
- return err
- }
- if err := task.SetSector(0); err != nil {
- return fmt.Errorf("Can't set sector")
- }
- if err := task.SetMessage(fmt.Sprintf("delete %d", deviceId)); err != nil {
- return fmt.Errorf("Can't set message")
- }
- if err := task.Run(); err != nil {
- return fmt.Errorf("Error running deleteDevice")
- }
- return nil
- }
- func removeDevice(name string) error {
- utils.Debugf("[devmapper] removeDevice START")
- defer utils.Debugf("[devmapper] removeDevice END")
- task, err := createTask(DeviceRemove, name)
- if task == nil {
- return err
- }
- if err = task.Run(); err != nil {
- return fmt.Errorf("Error running removeDevice")
- }
- return nil
- }
- func activateDevice(poolName string, name string, deviceId int, size uint64) error {
- task, err := createTask(DeviceCreate, name)
- if task == nil {
- return err
- }
- params := fmt.Sprintf("%s %d", poolName, deviceId)
- if err := task.AddTarget(0, size/512, "thin", params); err != nil {
- return fmt.Errorf("Can't add target")
- }
- if err := task.SetAddNode(AddNodeOnCreate); err != nil {
- return fmt.Errorf("Can't add node")
- }
- var cookie uint32 = 0
- if err := task.SetCookie(&cookie, 0); err != nil {
- return fmt.Errorf("Can't set cookie")
- }
- if err := task.Run(); err != nil {
- return fmt.Errorf("Error running DeviceCreate")
- }
- UdevWait(cookie)
- return nil
- }
- func (devices *DeviceSet) createSnapDevice(poolName string, deviceId int, baseName string, baseDeviceId int) error {
- devinfo, _ := getInfo(baseName)
- doSuspend := devinfo != nil && devinfo.Exists != 0
- if doSuspend {
- if err := suspendDevice(baseName); err != nil {
- return err
- }
- }
- task, err := createTask(DeviceTargetMsg, poolName)
- if task == nil {
- if doSuspend {
- resumeDevice(baseName)
- }
- return err
- }
- if err := task.SetSector(0); err != nil {
- if doSuspend {
- resumeDevice(baseName)
- }
- return fmt.Errorf("Can't set sector")
- }
- if err := task.SetMessage(fmt.Sprintf("create_snap %d %d", deviceId, baseDeviceId)); err != nil {
- if doSuspend {
- resumeDevice(baseName)
- }
- return fmt.Errorf("Can't set message")
- }
- if err := task.Run(); err != nil {
- if doSuspend {
- resumeDevice(baseName)
- }
- return fmt.Errorf("Error running DeviceCreate")
- }
- if doSuspend {
- if err := resumeDevice(baseName); err != nil {
- return err
- }
- }
- return nil
- }
|