github.com/kaisenlinux/docker.io@v0.0.0-20230510090727-ea55db55fac7/engine/pkg/devicemapper/devmapper_wrapper.go (about)

     1  //go:build linux && cgo
     2  // +build linux,cgo
     3  
     4  package devicemapper // import "github.com/docker/docker/pkg/devicemapper"
     5  
     6  /*
     7  #define _GNU_SOURCE
     8  #include <libdevmapper.h>
     9  #include <linux/fs.h>   // FIXME: present only for BLKGETSIZE64, maybe we can remove it?
    10  
    11  // FIXME: Can't we find a way to do the logging in pure Go?
    12  extern void DevmapperLogCallback(int level, char *file, int line, int dm_errno_or_class, char *str);
    13  
    14  static void	log_cb(int level, const char *file, int line, int dm_errno_or_class, const char *f, ...)
    15  {
    16  	char *buffer = NULL;
    17  	va_list ap;
    18  	int ret;
    19  
    20  	va_start(ap, f);
    21  	ret = vasprintf(&buffer, f, ap);
    22  	va_end(ap);
    23  	if (ret < 0) {
    24  		// memory allocation failed -- should never happen?
    25  		return;
    26  	}
    27  
    28  	DevmapperLogCallback(level, (char *)file, line, dm_errno_or_class, buffer);
    29  	free(buffer);
    30  }
    31  
    32  static void	log_with_errno_init()
    33  {
    34  	dm_log_with_errno_init(log_cb);
    35  }
    36  */
    37  import "C"
    38  
    39  import (
    40  	"reflect"
    41  	"unsafe"
    42  )
    43  
    44  type (
    45  	cdmTask C.struct_dm_task
    46  )
    47  
    48  // IOCTL consts
    49  const (
    50  	BlkGetSize64 = C.BLKGETSIZE64
    51  	BlkDiscard   = C.BLKDISCARD
    52  )
    53  
    54  // Devicemapper cookie flags.
    55  const (
    56  	DmUdevDisableSubsystemRulesFlag = C.DM_UDEV_DISABLE_SUBSYSTEM_RULES_FLAG
    57  	DmUdevDisableDiskRulesFlag      = C.DM_UDEV_DISABLE_DISK_RULES_FLAG
    58  	DmUdevDisableOtherRulesFlag     = C.DM_UDEV_DISABLE_OTHER_RULES_FLAG
    59  	DmUdevDisableLibraryFallback    = C.DM_UDEV_DISABLE_LIBRARY_FALLBACK
    60  )
    61  
    62  // DeviceMapper mapped functions.
    63  var (
    64  	DmGetLibraryVersion       = dmGetLibraryVersionFct
    65  	DmGetNextTarget           = dmGetNextTargetFct
    66  	DmSetDevDir               = dmSetDevDirFct
    67  	DmTaskAddTarget           = dmTaskAddTargetFct
    68  	DmTaskCreate              = dmTaskCreateFct
    69  	DmTaskDestroy             = dmTaskDestroyFct
    70  	DmTaskGetDeps             = dmTaskGetDepsFct
    71  	DmTaskGetInfo             = dmTaskGetInfoFct
    72  	DmTaskGetDriverVersion    = dmTaskGetDriverVersionFct
    73  	DmTaskRun                 = dmTaskRunFct
    74  	DmTaskSetAddNode          = dmTaskSetAddNodeFct
    75  	DmTaskSetCookie           = dmTaskSetCookieFct
    76  	DmTaskSetMessage          = dmTaskSetMessageFct
    77  	DmTaskSetName             = dmTaskSetNameFct
    78  	DmTaskSetSector           = dmTaskSetSectorFct
    79  	DmUdevWait                = dmUdevWaitFct
    80  	DmUdevSetSyncSupport      = dmUdevSetSyncSupportFct
    81  	DmUdevGetSyncSupport      = dmUdevGetSyncSupportFct
    82  	DmCookieSupported         = dmCookieSupportedFct
    83  	LogWithErrnoInit          = logWithErrnoInitFct
    84  	DmTaskDeferredRemove      = dmTaskDeferredRemoveFct
    85  	DmTaskGetInfoWithDeferred = dmTaskGetInfoWithDeferredFct
    86  )
    87  
    88  func free(p *C.char) {
    89  	C.free(unsafe.Pointer(p))
    90  }
    91  
    92  func dmTaskDestroyFct(task *cdmTask) {
    93  	C.dm_task_destroy((*C.struct_dm_task)(task))
    94  }
    95  
    96  func dmTaskCreateFct(taskType int) *cdmTask {
    97  	return (*cdmTask)(C.dm_task_create(C.int(taskType)))
    98  }
    99  
   100  func dmTaskRunFct(task *cdmTask) int {
   101  	ret, _ := C.dm_task_run((*C.struct_dm_task)(task))
   102  	return int(ret)
   103  }
   104  
   105  func dmTaskSetNameFct(task *cdmTask, name string) int {
   106  	Cname := C.CString(name)
   107  	defer free(Cname)
   108  
   109  	return int(C.dm_task_set_name((*C.struct_dm_task)(task), Cname))
   110  }
   111  
   112  func dmTaskSetMessageFct(task *cdmTask, message string) int {
   113  	Cmessage := C.CString(message)
   114  	defer free(Cmessage)
   115  
   116  	return int(C.dm_task_set_message((*C.struct_dm_task)(task), Cmessage))
   117  }
   118  
   119  func dmTaskSetSectorFct(task *cdmTask, sector uint64) int {
   120  	return int(C.dm_task_set_sector((*C.struct_dm_task)(task), C.uint64_t(sector)))
   121  }
   122  
   123  func dmTaskSetCookieFct(task *cdmTask, cookie *uint, flags uint16) int {
   124  	cCookie := C.uint32_t(*cookie)
   125  	defer func() {
   126  		*cookie = uint(cCookie)
   127  	}()
   128  	return int(C.dm_task_set_cookie((*C.struct_dm_task)(task), &cCookie, C.uint16_t(flags)))
   129  }
   130  
   131  func dmTaskSetAddNodeFct(task *cdmTask, addNode AddNodeType) int {
   132  	return int(C.dm_task_set_add_node((*C.struct_dm_task)(task), C.dm_add_node_t(addNode)))
   133  }
   134  
   135  func dmTaskAddTargetFct(task *cdmTask,
   136  	start, size uint64, ttype, params string) int {
   137  
   138  	Cttype := C.CString(ttype)
   139  	defer free(Cttype)
   140  
   141  	Cparams := C.CString(params)
   142  	defer free(Cparams)
   143  
   144  	return int(C.dm_task_add_target((*C.struct_dm_task)(task), C.uint64_t(start), C.uint64_t(size), Cttype, Cparams))
   145  }
   146  
   147  func dmTaskGetDepsFct(task *cdmTask) *Deps {
   148  	Cdeps := C.dm_task_get_deps((*C.struct_dm_task)(task))
   149  	if Cdeps == nil {
   150  		return nil
   151  	}
   152  
   153  	// golang issue: https://github.com/golang/go/issues/11925
   154  	var devices []C.uint64_t
   155  	devicesHdr := (*reflect.SliceHeader)(unsafe.Pointer(&devices))
   156  	devicesHdr.Data = uintptr(unsafe.Pointer(uintptr(unsafe.Pointer(Cdeps)) + unsafe.Sizeof(*Cdeps)))
   157  	devicesHdr.Len = int(Cdeps.count)
   158  	devicesHdr.Cap = int(Cdeps.count)
   159  
   160  	deps := &Deps{
   161  		Count:  uint32(Cdeps.count),
   162  		Filler: uint32(Cdeps.filler),
   163  	}
   164  	for _, device := range devices {
   165  		deps.Device = append(deps.Device, uint64(device))
   166  	}
   167  	return deps
   168  }
   169  
   170  func dmTaskGetInfoFct(task *cdmTask, info *Info) int {
   171  	Cinfo := C.struct_dm_info{}
   172  	defer func() {
   173  		info.Exists = int(Cinfo.exists)
   174  		info.Suspended = int(Cinfo.suspended)
   175  		info.LiveTable = int(Cinfo.live_table)
   176  		info.InactiveTable = int(Cinfo.inactive_table)
   177  		info.OpenCount = int32(Cinfo.open_count)
   178  		info.EventNr = uint32(Cinfo.event_nr)
   179  		info.Major = uint32(Cinfo.major)
   180  		info.Minor = uint32(Cinfo.minor)
   181  		info.ReadOnly = int(Cinfo.read_only)
   182  		info.TargetCount = int32(Cinfo.target_count)
   183  	}()
   184  	return int(C.dm_task_get_info((*C.struct_dm_task)(task), &Cinfo))
   185  }
   186  
   187  func dmTaskGetDriverVersionFct(task *cdmTask) string {
   188  	buffer := C.malloc(128)
   189  	defer C.free(buffer)
   190  	res := C.dm_task_get_driver_version((*C.struct_dm_task)(task), (*C.char)(buffer), 128)
   191  	if res == 0 {
   192  		return ""
   193  	}
   194  	return C.GoString((*C.char)(buffer))
   195  }
   196  
   197  func dmGetNextTargetFct(task *cdmTask, next unsafe.Pointer, start, length *uint64, target, params *string) unsafe.Pointer {
   198  	var (
   199  		Cstart, Clength      C.uint64_t
   200  		CtargetType, Cparams *C.char
   201  	)
   202  	defer func() {
   203  		*start = uint64(Cstart)
   204  		*length = uint64(Clength)
   205  		*target = C.GoString(CtargetType)
   206  		*params = C.GoString(Cparams)
   207  	}()
   208  
   209  	//lint:ignore SA4000 false positive on (identical expressions on the left and right side of the '==' operator) (staticcheck)
   210  	nextp := C.dm_get_next_target((*C.struct_dm_task)(task), next, &Cstart, &Clength, &CtargetType, &Cparams)
   211  	return nextp
   212  }
   213  
   214  func dmUdevSetSyncSupportFct(syncWithUdev int) {
   215  	C.dm_udev_set_sync_support(C.int(syncWithUdev))
   216  }
   217  
   218  func dmUdevGetSyncSupportFct() int {
   219  	return int(C.dm_udev_get_sync_support())
   220  }
   221  
   222  func dmUdevWaitFct(cookie uint) int {
   223  	return int(C.dm_udev_wait(C.uint32_t(cookie)))
   224  }
   225  
   226  func dmCookieSupportedFct() int {
   227  	return int(C.dm_cookie_supported())
   228  }
   229  
   230  func logWithErrnoInitFct() {
   231  	C.log_with_errno_init()
   232  }
   233  
   234  func dmSetDevDirFct(dir string) int {
   235  	Cdir := C.CString(dir)
   236  	defer free(Cdir)
   237  
   238  	return int(C.dm_set_dev_dir(Cdir))
   239  }
   240  
   241  func dmGetLibraryVersionFct(version *string) int {
   242  	buffer := C.CString(string(make([]byte, 128)))
   243  	defer free(buffer)
   244  	defer func() {
   245  		*version = C.GoString(buffer)
   246  	}()
   247  	return int(C.dm_get_library_version(buffer, 128))
   248  }