unix: implement SyncFileRange for ARM

Change-Id: I5a98a732c0e6a229ab93acbce08b4f780f860f72
GitHub-Last-Rev: 886bffd986fbb7be149e7df3bda65331a74db0b8
GitHub-Pull-Request: golang/sys#16
Reviewed-on: https://go-review.googlesource.com/133015
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

unix/syscall_linux_arm.go

@@ -141,6 +141,7 @@ func Fadvise(fd int, offset int64, length int64, advice int) (err error) {
 }
 
 //sys	mmap2(addr uintptr, length uintptr, prot int, flags int, fd int, pageOffset uintptr) (xaddr uintptr, err error)
+//sys	SyncFileRange(fd int, off int64, n int64, flags int) (err error) = SYS_ARM_SYNC_FILE_RANGE
 
 func Fstatfs(fd int, buf *Statfs_t) (err error) {
 	_, _, e := Syscall(SYS_FSTATFS64, uintptr(fd), unsafe.Sizeof(*buf), uintptr(unsafe.Pointer(buf)))

unix/zsyscall_linux_arm.go

@@ -2177,6 +2177,16 @@ func mmap2(addr uintptr, length uintptr, prot int, flags int, fd int, pageOffset
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func SyncFileRange(fd int, off int64, n int64, flags int) (err error) {
+	_, _, e1 := Syscall9(SYS_ARM_SYNC_FILE_RANGE, uintptr(fd), 0, uintptr(off), uintptr(off>>32), uintptr(n), uintptr(n>>32), uintptr(flags), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func getrlimit(resource int, rlim *rlimit32) (err error) {
 	_, _, e1 := RawSyscall(SYS_UGETRLIMIT, uintptr(resource), uintptr(unsafe.Pointer(rlim)), 0)
 	if e1 != 0 {