diff --git a/unix/ioctl_linux.go b/unix/ioctl_linux.go
new file mode 100644
index 0000000..48773f7
--- /dev/null
+++ b/unix/ioctl_linux.go
@@ -0,0 +1,196 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package unix
+
+import (
+	"runtime"
+	"unsafe"
+)
+
+// IoctlRetInt performs an ioctl operation specified by req on a device
+// associated with opened file descriptor fd, and returns a non-negative
+// integer that is returned by the ioctl syscall.
+func IoctlRetInt(fd int, req uint) (int, error) {
+	ret, _, err := Syscall(SYS_IOCTL, uintptr(fd), uintptr(req), 0)
+	if err != 0 {
+		return 0, err
+	}
+	return int(ret), nil
+}
+
+func IoctlGetUint32(fd int, req uint) (uint32, error) {
+	var value uint32
+	err := ioctl(fd, req, uintptr(unsafe.Pointer(&value)))
+	return value, err
+}
+
+func IoctlGetRTCTime(fd int) (*RTCTime, error) {
+	var value RTCTime
+	err := ioctl(fd, RTC_RD_TIME, uintptr(unsafe.Pointer(&value)))
+	return &value, err
+}
+
+func IoctlSetRTCTime(fd int, value *RTCTime) error {
+	err := ioctl(fd, RTC_SET_TIME, uintptr(unsafe.Pointer(value)))
+	runtime.KeepAlive(value)
+	return err
+}
+
+func IoctlGetRTCWkAlrm(fd int) (*RTCWkAlrm, error) {
+	var value RTCWkAlrm
+	err := ioctl(fd, RTC_WKALM_RD, uintptr(unsafe.Pointer(&value)))
+	return &value, err
+}
+
+func IoctlSetRTCWkAlrm(fd int, value *RTCWkAlrm) error {
+	err := ioctl(fd, RTC_WKALM_SET, uintptr(unsafe.Pointer(value)))
+	runtime.KeepAlive(value)
+	return err
+}
+
+type ifreqEthtool struct {
+	name [IFNAMSIZ]byte
+	data unsafe.Pointer
+}
+
+// IoctlGetEthtoolDrvinfo fetches ethtool driver information for the network
+// device specified by ifname.
+func IoctlGetEthtoolDrvinfo(fd int, ifname string) (*EthtoolDrvinfo, error) {
+	// Leave room for terminating NULL byte.
+	if len(ifname) >= IFNAMSIZ {
+		return nil, EINVAL
+	}
+
+	value := EthtoolDrvinfo{
+		Cmd: ETHTOOL_GDRVINFO,
+	}
+	ifreq := ifreqEthtool{
+		data: unsafe.Pointer(&value),
+	}
+	copy(ifreq.name[:], ifname)
+	err := ioctl(fd, SIOCETHTOOL, uintptr(unsafe.Pointer(&ifreq)))
+	runtime.KeepAlive(ifreq)
+	return &value, err
+}
+
+// IoctlGetWatchdogInfo fetches information about a watchdog device from the
+// Linux watchdog API. For more information, see:
+// https://www.kernel.org/doc/html/latest/watchdog/watchdog-api.html.
+func IoctlGetWatchdogInfo(fd int) (*WatchdogInfo, error) {
+	var value WatchdogInfo
+	err := ioctl(fd, WDIOC_GETSUPPORT, uintptr(unsafe.Pointer(&value)))
+	return &value, err
+}
+
+// IoctlWatchdogKeepalive issues a keepalive ioctl to a watchdog device. For
+// more information, see:
+// https://www.kernel.org/doc/html/latest/watchdog/watchdog-api.html.
+func IoctlWatchdogKeepalive(fd int) error {
+	return ioctl(fd, WDIOC_KEEPALIVE, 0)
+}
+
+// IoctlFileCloneRange performs an FICLONERANGE ioctl operation to clone the
+// range of data conveyed in value to the file associated with the file
+// descriptor destFd. See the ioctl_ficlonerange(2) man page for details.
+func IoctlFileCloneRange(destFd int, value *FileCloneRange) error {
+	err := ioctl(destFd, FICLONERANGE, uintptr(unsafe.Pointer(value)))
+	runtime.KeepAlive(value)
+	return err
+}
+
+// IoctlFileClone performs an FICLONE ioctl operation to clone the entire file
+// associated with the file description srcFd to the file associated with the
+// file descriptor destFd. See the ioctl_ficlone(2) man page for details.
+func IoctlFileClone(destFd, srcFd int) error {
+	return ioctl(destFd, FICLONE, uintptr(srcFd))
+}
+
+type FileDedupeRange struct {
+	Src_offset uint64
+	Src_length uint64
+	Reserved1  uint16
+	Reserved2  uint32
+	Info       []FileDedupeRangeInfo
+}
+
+type FileDedupeRangeInfo struct {
+	Dest_fd       int64
+	Dest_offset   uint64
+	Bytes_deduped uint64
+	Status        int32
+	Reserved      uint32
+}
+
+// IoctlFileDedupeRange performs an FIDEDUPERANGE ioctl operation to share the
+// range of data conveyed in value from the file associated with the file
+// descriptor srcFd to the value.Info destinations. See the
+// ioctl_fideduperange(2) man page for details.
+func IoctlFileDedupeRange(srcFd int, value *FileDedupeRange) error {
+	buf := make([]byte, SizeofRawFileDedupeRange+
+		len(value.Info)*SizeofRawFileDedupeRangeInfo)
+	rawrange := (*RawFileDedupeRange)(unsafe.Pointer(&buf[0]))
+	rawrange.Src_offset = value.Src_offset
+	rawrange.Src_length = value.Src_length
+	rawrange.Dest_count = uint16(len(value.Info))
+	rawrange.Reserved1 = value.Reserved1
+	rawrange.Reserved2 = value.Reserved2
+
+	for i := range value.Info {
+		rawinfo := (*RawFileDedupeRangeInfo)(unsafe.Pointer(
+			uintptr(unsafe.Pointer(&buf[0])) + uintptr(SizeofRawFileDedupeRange) +
+				uintptr(i*SizeofRawFileDedupeRangeInfo)))
+		rawinfo.Dest_fd = value.Info[i].Dest_fd
+		rawinfo.Dest_offset = value.Info[i].Dest_offset
+		rawinfo.Bytes_deduped = value.Info[i].Bytes_deduped
+		rawinfo.Status = value.Info[i].Status
+		rawinfo.Reserved = value.Info[i].Reserved
+	}
+
+	err := ioctl(srcFd, FIDEDUPERANGE, uintptr(unsafe.Pointer(&buf[0])))
+
+	// Output
+	for i := range value.Info {
+		rawinfo := (*RawFileDedupeRangeInfo)(unsafe.Pointer(
+			uintptr(unsafe.Pointer(&buf[0])) + uintptr(SizeofRawFileDedupeRange) +
+				uintptr(i*SizeofRawFileDedupeRangeInfo)))
+		value.Info[i].Dest_fd = rawinfo.Dest_fd
+		value.Info[i].Dest_offset = rawinfo.Dest_offset
+		value.Info[i].Bytes_deduped = rawinfo.Bytes_deduped
+		value.Info[i].Status = rawinfo.Status
+		value.Info[i].Reserved = rawinfo.Reserved
+	}
+
+	return err
+}
+
+func IoctlHIDGetDesc(fd int, value *HIDRawReportDescriptor) error {
+	err := ioctl(fd, HIDIOCGRDESC, uintptr(unsafe.Pointer(value)))
+	runtime.KeepAlive(value)
+	return err
+}
+
+func IoctlHIDGetRawInfo(fd int) (*HIDRawDevInfo, error) {
+	var value HIDRawDevInfo
+	err := ioctl(fd, HIDIOCGRAWINFO, uintptr(unsafe.Pointer(&value)))
+	return &value, err
+}
+
+func IoctlHIDGetRawName(fd int) (string, error) {
+	var value [_HIDIOCGRAWNAME_LEN]byte
+	err := ioctl(fd, _HIDIOCGRAWNAME, uintptr(unsafe.Pointer(&value[0])))
+	return ByteSliceToString(value[:]), err
+}
+
+func IoctlHIDGetRawPhys(fd int) (string, error) {
+	var value [_HIDIOCGRAWPHYS_LEN]byte
+	err := ioctl(fd, _HIDIOCGRAWPHYS, uintptr(unsafe.Pointer(&value[0])))
+	return ByteSliceToString(value[:]), err
+}
+
+func IoctlHIDGetRawUniq(fd int) (string, error) {
+	var value [_HIDIOCGRAWUNIQ_LEN]byte
+	err := ioctl(fd, _HIDIOCGRAWUNIQ, uintptr(unsafe.Pointer(&value[0])))
+	return ByteSliceToString(value[:]), err
+}
diff --git a/unix/syscall_linux.go b/unix/syscall_linux.go
index c61c963..4263953 100644
--- a/unix/syscall_linux.go
+++ b/unix/syscall_linux.go
@@ -70,192 +70,7 @@
 
 // ioctl itself should not be exposed directly, but additional get/set
 // functions for specific types are permissible.
-
-// IoctlRetInt performs an ioctl operation specified by req on a device
-// associated with opened file descriptor fd, and returns a non-negative
-// integer that is returned by the ioctl syscall.
-func IoctlRetInt(fd int, req uint) (int, error) {
-	ret, _, err := Syscall(SYS_IOCTL, uintptr(fd), uintptr(req), 0)
-	if err != 0 {
-		return 0, err
-	}
-	return int(ret), nil
-}
-
-func IoctlSetRTCTime(fd int, value *RTCTime) error {
-	err := ioctl(fd, RTC_SET_TIME, uintptr(unsafe.Pointer(value)))
-	runtime.KeepAlive(value)
-	return err
-}
-
-func IoctlSetRTCWkAlrm(fd int, value *RTCWkAlrm) error {
-	err := ioctl(fd, RTC_WKALM_SET, uintptr(unsafe.Pointer(value)))
-	runtime.KeepAlive(value)
-	return err
-}
-
-func IoctlGetUint32(fd int, req uint) (uint32, error) {
-	var value uint32
-	err := ioctl(fd, req, uintptr(unsafe.Pointer(&value)))
-	return value, err
-}
-
-func IoctlGetRTCTime(fd int) (*RTCTime, error) {
-	var value RTCTime
-	err := ioctl(fd, RTC_RD_TIME, uintptr(unsafe.Pointer(&value)))
-	return &value, err
-}
-
-type ifreqEthtool struct {
-	name [IFNAMSIZ]byte
-	data unsafe.Pointer
-}
-
-// IoctlGetEthtoolDrvinfo fetches ethtool driver information for the network
-// device specified by ifname.
-func IoctlGetEthtoolDrvinfo(fd int, ifname string) (*EthtoolDrvinfo, error) {
-	// Leave room for terminating NULL byte.
-	if len(ifname) >= IFNAMSIZ {
-		return nil, EINVAL
-	}
-
-	value := EthtoolDrvinfo{
-		Cmd: ETHTOOL_GDRVINFO,
-	}
-	ifreq := ifreqEthtool{
-		data: unsafe.Pointer(&value),
-	}
-	copy(ifreq.name[:], ifname)
-	err := ioctl(fd, SIOCETHTOOL, uintptr(unsafe.Pointer(&ifreq)))
-	runtime.KeepAlive(ifreq)
-	return &value, err
-}
-
-// IoctlGetWatchdogInfo fetches information about a watchdog device from the
-// Linux watchdog API. For more information, see:
-// https://www.kernel.org/doc/html/latest/watchdog/watchdog-api.html.
-func IoctlGetWatchdogInfo(fd int) (*WatchdogInfo, error) {
-	var value WatchdogInfo
-	err := ioctl(fd, WDIOC_GETSUPPORT, uintptr(unsafe.Pointer(&value)))
-	return &value, err
-}
-
-func IoctlGetRTCWkAlrm(fd int) (*RTCWkAlrm, error) {
-	var value RTCWkAlrm
-	err := ioctl(fd, RTC_WKALM_RD, uintptr(unsafe.Pointer(&value)))
-	return &value, err
-}
-
-// IoctlFileCloneRange performs an FICLONERANGE ioctl operation to clone the
-// range of data conveyed in value to the file associated with the file
-// descriptor destFd. See the ioctl_ficlonerange(2) man page for details.
-func IoctlFileCloneRange(destFd int, value *FileCloneRange) error {
-	err := ioctl(destFd, FICLONERANGE, uintptr(unsafe.Pointer(value)))
-	runtime.KeepAlive(value)
-	return err
-}
-
-// IoctlFileClone performs an FICLONE ioctl operation to clone the entire file
-// associated with the file description srcFd to the file associated with the
-// file descriptor destFd. See the ioctl_ficlone(2) man page for details.
-func IoctlFileClone(destFd, srcFd int) error {
-	return ioctl(destFd, FICLONE, uintptr(srcFd))
-}
-
-type FileDedupeRange struct {
-	Src_offset uint64
-	Src_length uint64
-	Reserved1  uint16
-	Reserved2  uint32
-	Info       []FileDedupeRangeInfo
-}
-
-type FileDedupeRangeInfo struct {
-	Dest_fd       int64
-	Dest_offset   uint64
-	Bytes_deduped uint64
-	Status        int32
-	Reserved      uint32
-}
-
-// IoctlFileDedupeRange performs an FIDEDUPERANGE ioctl operation to share the
-// range of data conveyed in value from the file associated with the file
-// descriptor srcFd to the value.Info destinations. See the
-// ioctl_fideduperange(2) man page for details.
-func IoctlFileDedupeRange(srcFd int, value *FileDedupeRange) error {
-	buf := make([]byte, SizeofRawFileDedupeRange+
-		len(value.Info)*SizeofRawFileDedupeRangeInfo)
-	rawrange := (*RawFileDedupeRange)(unsafe.Pointer(&buf[0]))
-	rawrange.Src_offset = value.Src_offset
-	rawrange.Src_length = value.Src_length
-	rawrange.Dest_count = uint16(len(value.Info))
-	rawrange.Reserved1 = value.Reserved1
-	rawrange.Reserved2 = value.Reserved2
-
-	for i := range value.Info {
-		rawinfo := (*RawFileDedupeRangeInfo)(unsafe.Pointer(
-			uintptr(unsafe.Pointer(&buf[0])) + uintptr(SizeofRawFileDedupeRange) +
-				uintptr(i*SizeofRawFileDedupeRangeInfo)))
-		rawinfo.Dest_fd = value.Info[i].Dest_fd
-		rawinfo.Dest_offset = value.Info[i].Dest_offset
-		rawinfo.Bytes_deduped = value.Info[i].Bytes_deduped
-		rawinfo.Status = value.Info[i].Status
-		rawinfo.Reserved = value.Info[i].Reserved
-	}
-
-	err := ioctl(srcFd, FIDEDUPERANGE, uintptr(unsafe.Pointer(&buf[0])))
-
-	// Output
-	for i := range value.Info {
-		rawinfo := (*RawFileDedupeRangeInfo)(unsafe.Pointer(
-			uintptr(unsafe.Pointer(&buf[0])) + uintptr(SizeofRawFileDedupeRange) +
-				uintptr(i*SizeofRawFileDedupeRangeInfo)))
-		value.Info[i].Dest_fd = rawinfo.Dest_fd
-		value.Info[i].Dest_offset = rawinfo.Dest_offset
-		value.Info[i].Bytes_deduped = rawinfo.Bytes_deduped
-		value.Info[i].Status = rawinfo.Status
-		value.Info[i].Reserved = rawinfo.Reserved
-	}
-
-	return err
-}
-
-// IoctlWatchdogKeepalive issues a keepalive ioctl to a watchdog device. For
-// more information, see:
-// https://www.kernel.org/doc/html/latest/watchdog/watchdog-api.html.
-func IoctlWatchdogKeepalive(fd int) error {
-	return ioctl(fd, WDIOC_KEEPALIVE, 0)
-}
-
-func IoctlHIDGetDesc(fd int, value *HIDRawReportDescriptor) error {
-	err := ioctl(fd, HIDIOCGRDESC, uintptr(unsafe.Pointer(value)))
-	runtime.KeepAlive(value)
-	return err
-}
-
-func IoctlHIDGetRawInfo(fd int) (*HIDRawDevInfo, error) {
-	var value HIDRawDevInfo
-	err := ioctl(fd, HIDIOCGRAWINFO, uintptr(unsafe.Pointer(&value)))
-	return &value, err
-}
-
-func IoctlHIDGetRawName(fd int) (string, error) {
-	var value [_HIDIOCGRAWNAME_LEN]byte
-	err := ioctl(fd, _HIDIOCGRAWNAME, uintptr(unsafe.Pointer(&value[0])))
-	return ByteSliceToString(value[:]), err
-}
-
-func IoctlHIDGetRawPhys(fd int) (string, error) {
-	var value [_HIDIOCGRAWPHYS_LEN]byte
-	err := ioctl(fd, _HIDIOCGRAWPHYS, uintptr(unsafe.Pointer(&value[0])))
-	return ByteSliceToString(value[:]), err
-}
-
-func IoctlHIDGetRawUniq(fd int) (string, error) {
-	var value [_HIDIOCGRAWUNIQ_LEN]byte
-	err := ioctl(fd, _HIDIOCGRAWUNIQ, uintptr(unsafe.Pointer(&value[0])))
-	return ByteSliceToString(value[:]), err
-}
+// These are defined in ioctl.go and ioctl_linux.go.
 
 //sys	Linkat(olddirfd int, oldpath string, newdirfd int, newpath string, flags int) (err error)