Extract ioctl from wrapper

graphdriver/devmapper/attachLoopback.go

@@ -3,63 +3,14 @@ package devmapper
 import (
 	"fmt"
 	"github.com/dotcloud/docker/utils"
-	"unsafe"
 )
 
-func ioctlLoopCtlGetFree(fd uintptr) (int, error) {
+func stringToLoopName(src string) [LoNameSize]uint8 {
-	index, _, err := sysSyscall(sysSysIoctl, fd, LoopCtlGetFree, 0)
+	var dst [LoNameSize]uint8
-	if err != 0 {
+	copy(dst[:], src[:])
-		return 0, err
+	return dst
-	}
-	return int(index), nil
 }
 
-func ioctlLoopSetFd(loopFd, sparseFd uintptr) error {
-	if _, _, err := sysSyscall(sysSysIoctl, loopFd, LoopSetFd, sparseFd); err != 0 {
-		return err
-	}
-	return nil
-}
-
-func ioctlLoopSetStatus64(loopFd uintptr, loopInfo *LoopInfo64) error {
-	_, _, err := sysSyscall(sysSysIoctl, loopFd, LoopSetStatus64, uintptr(unsafe.Pointer(loopInfo)))
-	if err != 0 {
-		return err
-	}
-	return nil
-}
-
-func ioctlLoopClrFd(loopFd uintptr) error {
-	_, _, err := sysSyscall(sysSysIoctl, loopFd, LoopClrFd, 0)
-	if err != 0 {
-		return err
-	}
-	return nil
-}
-
-// //func dmGetLoopbackBackingFileFct(fd uintptr) (uint64, uint64, sysErrno) {
-// func ioctlLoopGetStatus64(loopFd uintptr) (*LoopInfo64, error) {
-// 	var lo64 C.struct_loop_info64
-// 	_, _, err := sysSyscall(sysSysIoctl, fd, C.LOOP_GET_STATUS64, uintptr(unsafe.Pointer(&lo64)))
-// 	return uint64(lo64.lo_device), uint64(lo64.lo_inode), sysErrno(err)
-// }
-
-// func dmLoopbackSetCapacityFct(fd uintptr) sysErrno {
-// 	_, _, err := sysSyscall(sysSysIoctl, fd, C.LOOP_SET_CAPACITY, 0)
-// 	return sysErrno(err)
-// }
-
-// func dmGetBlockSizeFct(fd uintptr) (int64, sysErrno) {
-// 	var size int64
-// 	_, _, err := sysSyscall(sysSysIoctl, fd, C.BLKGETSIZE64, uintptr(unsafe.Pointer(&size)))
-// 	return size, sysErrno(err)
-// }
-
-// func getBlockSizeFct(fd uintptr, size *uint64) sysErrno {
-// 	_, _, err := sysSyscall(sysSysIoctl, fd, C.BLKGETSIZE64, uintptr(unsafe.Pointer(&size)))
-// 	return sysErrno(err)
-// }
-
 func getNextFreeLoopbackIndex() (int, error) {
 	f, err := osOpenFile("/dev/loop-control", osORdOnly, 0644)
 	if err != nil {
@@ -125,12 +76,6 @@ func openNextAvailableLoopback(index int, sparseFile *osFile) (loopFile *osFile,
 	return loopFile, nil
 }
 
-func stringToLoopName(src string) [LoNameSize]uint8 {
-	var dst [LoNameSize]uint8
-	copy(dst[:], src[:])
-	return dst
-}
-
 // attachLoopDevice attaches the given sparse file to the next
 // available loopback device. It returns an opened *osFile.
 func attachLoopDevice(sparseName string) (loop *osFile, err error) {

graphdriver/devmapper/devmapper.go

@@ -178,15 +178,17 @@ func (t *Task) GetNextTarget(next uintptr) (nextPtr uintptr, start uint64,
 }
 
 func getLoopbackBackingFile(file *osFile) (uint64, uint64, error) {
-	dev, inode, err := DmGetLoopbackBackingFile(file.Fd())
+	loopInfo, err := ioctlLoopGetStatus64(file.Fd())
-	if err != 0 {
+	if err != nil {
+		utils.Errorf("Error get loopback backing file: %s\n", err)
 		return 0, 0, ErrGetLoopbackBackingFile
 	}
-	return dev, inode, nil
+	return loopInfo.loDevice, loopInfo.loInode, nil
 }
 
 func LoopbackSetCapacity(file *osFile) error {
-	if err := DmLoopbackSetCapacity(file.Fd()); err != 0 {
+	if err := ioctlLoopSetCapacity(file.Fd(), 0); err != nil {
+		utils.Errorf("Error loopbackSetCapacity: %s", err)
 		return ErrLoopbackSetCapacity
 	}
 	return nil
@@ -276,8 +278,9 @@ func RemoveDevice(name string) error {
 }
 
 func GetBlockDeviceSize(file *osFile) (uint64, error) {
-	size, errno := DmGetBlockSize(file.Fd())
+	size, err := ioctlBlkGetSize64(file.Fd())
-	if size == -1 || errno != 0 {
+	if err != nil {
+		utils.Errorf("Error getblockdevicesize: %s", err)
 		return 0, ErrGetBlockSize
 	}
 	return uint64(size), nil

graphdriver/devmapper/devmapper_wrapper.go

@@ -34,6 +34,7 @@ import (
 
 type (
 	CDmTask C.struct_dm_task
+
 	CLoopInfo64 C.struct_loop_info64
 	LoopInfo64  struct {
 		loDevice           uint64 /* ioctl r/o */
@@ -56,17 +57,21 @@ type (
 const (
 	LoopSetFd       = C.LOOP_SET_FD
 	LoopCtlGetFree  = C.LOOP_CTL_GET_FREE
+	LoopGetStatus64 = C.LOOP_GET_STATUS64
 	LoopSetStatus64 = C.LOOP_SET_STATUS64
 	LoopClrFd       = C.LOOP_CLR_FD
+	LoopSetCapacity = C.LOOP_SET_CAPACITY
+
 	LoFlagsAutoClear = C.LO_FLAGS_AUTOCLEAR
 	LoFlagsReadOnly  = C.LO_FLAGS_READ_ONLY
 	LoFlagsPartScan  = C.LO_FLAGS_PARTSCAN
 	LoKeySize        = C.LO_KEY_SIZE
 	LoNameSize       = C.LO_NAME_SIZE
+
+	BlkGetSize64 = C.BLKGETSIZE64
 )
 
 var (
-	DmGetBlockSize           = dmGetBlockSizeFct
 	DmGetLibraryVersion = dmGetLibraryVersionFct
 	DmGetNextTarget     = dmGetNextTargetFct
 	DmLogInitVerbose    = dmLogInitVerboseFct
@@ -83,10 +88,7 @@ var (
 	DmTaskSetRo         = dmTaskSetRoFct
 	DmTaskSetSector     = dmTaskSetSectorFct
 	DmUdevWait          = dmUdevWaitFct
-	GetBlockSize             = getBlockSizeFct
 	LogWithErrnoInit    = logWithErrnoInitFct
-	DmGetLoopbackBackingFile = dmGetLoopbackBackingFileFct
-	DmLoopbackSetCapacity    = dmLoopbackSetCapacityFct
 )
 
 func free(p *C.char) {
@@ -185,28 +187,6 @@ func dmGetNextTargetFct(task *CDmTask, next uintptr, start, length *uint64, targ
 	return uintptr(nextp)
 }
 
-func dmGetLoopbackBackingFileFct(fd uintptr) (uint64, uint64, sysErrno) {
-	var lo64 C.struct_loop_info64
-	_, _, err := sysSyscall(sysSysIoctl, fd, C.LOOP_GET_STATUS64, uintptr(unsafe.Pointer(&lo64)))
-	return uint64(lo64.lo_device), uint64(lo64.lo_inode), sysErrno(err)
-}
-
-func dmLoopbackSetCapacityFct(fd uintptr) sysErrno {
-	_, _, err := sysSyscall(sysSysIoctl, fd, C.LOOP_SET_CAPACITY, 0)
-	return sysErrno(err)
-}
-
-func dmGetBlockSizeFct(fd uintptr) (int64, sysErrno) {
-	var size int64
-	_, _, err := sysSyscall(sysSysIoctl, fd, C.BLKGETSIZE64, uintptr(unsafe.Pointer(&size)))
-	return size, sysErrno(err)
-}
-
-func getBlockSizeFct(fd uintptr, size *uint64) sysErrno {
-	_, _, err := sysSyscall(sysSysIoctl, fd, C.BLKGETSIZE64, uintptr(unsafe.Pointer(&size)))
-	return sysErrno(err)
-}
-
 func dmUdevWaitFct(cookie uint) int {
 	return int(C.dm_udev_wait(C.uint32_t(cookie)))
 }

graphdriver/devmapper/ioctl.go

@@ -0,0 +1,58 @@
+package devmapper
+
+import (
+	"unsafe"
+)
+
+func ioctlLoopCtlGetFree(fd uintptr) (int, error) {
+	index, _, err := sysSyscall(sysSysIoctl, fd, LoopCtlGetFree, 0)
+	if err != 0 {
+		return 0, err
+	}
+	return int(index), nil
+}
+
+func ioctlLoopSetFd(loopFd, sparseFd uintptr) error {
+	if _, _, err := sysSyscall(sysSysIoctl, loopFd, LoopSetFd, sparseFd); err != 0 {
+		return err
+	}
+	return nil
+}
+
+func ioctlLoopSetStatus64(loopFd uintptr, loopInfo *LoopInfo64) error {
+	if _, _, err := sysSyscall(sysSysIoctl, loopFd, LoopSetStatus64, uintptr(unsafe.Pointer(loopInfo))); err != 0 {
+		return err
+	}
+	return nil
+}
+
+func ioctlLoopClrFd(loopFd uintptr) error {
+	if _, _, err := sysSyscall(sysSysIoctl, loopFd, LoopClrFd, 0); err != 0 {
+		return err
+	}
+	return nil
+}
+
+func ioctlLoopGetStatus64(loopFd uintptr) (*LoopInfo64, error) {
+	loopInfo := &LoopInfo64{}
+
+	if _, _, err := sysSyscall(sysSysIoctl, loopFd, LoopGetStatus64, uintptr(unsafe.Pointer(loopInfo))); err != 0 {
+		return nil, err
+	}
+	return loopInfo, nil
+}
+
+func ioctlLoopSetCapacity(loopFd uintptr, value int) error {
+	if _, _, err := sysSyscall(sysSysIoctl, loopFd, LoopSetCapacity, uintptr(value)); err != 0 {
+		return err
+	}
+	return nil
+}
+
+func ioctlBlkGetSize64(fd uintptr) (int64, error) {
+	var size int64
+	if _, _, err := sysSyscall(sysSysIoctl, fd, BlkGetSize64, uintptr(unsafe.Pointer(&size))); err != 0 {
+		return 0, err
+	}
+	return size, nil
+}