@@ -327,7 +327,18 @@ func setCloseOnExec(name string) {

 	}

 }

+func (devices *DeviceSetDM) log(level int, file string, line int, dmError int, message string)  {

+	if level >= 7 {

+		return // Ignore _LOG_DEBUG

+	}

+

+	utils.Debugf("libdevmapper(%d): %s:%d (%d) %s", level, file, line, dmError, message)

+}

+

+

 func (devices *DeviceSetDM) initDevmapper() error {

+	logInit(devices)

+

 	info, err := getInfo(devices.getPoolName())

 	if info == nil {

 		utils.Debugf("Error device getInfo: %s", err)

@@ -114,6 +114,28 @@ get_block_size(int fd)

   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"

@@ -127,6 +149,10 @@ import (

 	"unsafe"

 )

+type DevmapperLogger interface  {

+	log(level int, file string, line int, dmError int, message string)

+}

+

 const (

 	DeviceCreate TaskType = iota

 	DeviceReload

@@ -351,6 +377,13 @@ 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)

new file mode 100644

@@ -0,0 +1,13 @@

+package devmapper

+

+import "C"

+

+// Due to the way cgo works this has to be in a separate file, as devmapper.go has

+// definitions in the cgo block, which is incompatible with using "//export"

+

+//export DevmapperLogCallback

+func DevmapperLogCallback(level C.int, file *C.char, line C.int, dm_errno_or_class C.int, message *C.char) {

+	if dmLogger != nil {

+		dmLogger.log(int(level), C.GoString(file), int(line), int(dm_errno_or_class), C.GoString(message))

+	}

+}