//sys	Unlink(path string) (err error)
//sys	Unmount(path string, flags int) (err error)
//sys	write(fd int, p []byte) (n int, err error)
//sys   mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error)
//sys   munmap(addr uintptr, length uintptr) (err error)
//sys	readlen(fd int, buf *byte, nbuf int) (n int, err error) = SYS_READ

//sys	Unlink(path string) (err error)
//sys	Unmount(path string, flags int) (err error)
//sys	write(fd int, p []byte) (n int, err error)
//sys   mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error)
//sys   munmap(addr uintptr, length uintptr) (err error)
//sys	readlen(fd int, buf *byte, nbuf int) (n int, err error) = SYS_READ

  const void* const address;
  const uint64_t length;
} PosixMemoryRegion;

static void Cleanup(TF_ReadOnlyMemoryRegion* region) {
  auto r = static_cast<PosixMemoryRegion*>(region->plugin_memory_region);
  munmap(const_cast<void*>(r->address), r->length);
  delete r;
}

static const void* Data(const TF_ReadOnlyMemoryRegion* region) {
  auto r = static_cast<PosixMemoryRegion*>(region->plugin_memory_region);

//sys	Unlinkat(dirfd int, path string, flags int) (err error)
//sys	Unmount(path string, flags int) (err error)
//sys	write(fd int, p []byte) (n int, err error)
//sys	mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error)
//sys	munmap(addr uintptr, length uintptr) (err error)
//sys	utimensat(dirfd int, path string, times *[2]Timespec, flags int) (err error)

const (
	mremapFixed     = MAP_FIXED

	MOVW	off+28(FP), A5
	MOV	$SYS_mmap, T0
	ECALL
	BNE	T0, ZERO, fail
	MOV	A0, p+32(FP)
	MOV	ZERO, err+40(FP)
	RET
fail:
	MOV	ZERO, p+32(FP)
	MOV	A0, err+40(FP)
	RET

// func munmap(addr uintptr, n uintptr) (err error)
TEXT runtime·munmap(SB),NOSPLIT|NOFRAME,$0
	MOV	addr+0(FP), A0
	MOV	n+8(FP), A1
	MOV	$SYS_munmap, T0
	ECALL
	BNE	T0, ZERO, fail
	RET
fail:
	WORD	$0	// crash

//sys	Unmount(path string, flags int) (err error)
//sys	write(fd int, p []byte) (n int, err error)
//sys	writev(fd int, iovecs []Iovec) (cnt uintptr, err error)
//sys   mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error)
//sys   munmap(addr uintptr, length uintptr) (err error)
//sysnb fork() (pid int, err error)
//sysnb execve(path *byte, argv **byte, envp **byte) (err error)

	MOVW	off+28(FP), R5
	MOVD	$SYS_mmap, R8
	SVC
	BCS	fail
	MOVD	R0, p+32(FP)
	MOVD	$0, err+40(FP)
	RET
fail:
	MOVD	$0, p+32(FP)
	MOVD	R0, err+40(FP)
	RET

// func munmap(addr uintptr, n uintptr) (err error)
TEXT runtime·munmap(SB),NOSPLIT|NOFRAME,$0
	MOVD	addr+0(FP), R0
	MOVD	n+8(FP), R1
	MOVD	$SYS_munmap, R8
	SVC
	BCS	fail
	RET
fail:
	MOVD	$0, R0

//sys	Unlinkat(dirfd int, path string, flags int) (err error)
//sys	Unmount(path string, flags int) (err error)
//sys	write(fd int, p []byte) (n int, err error)
//sys	mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error)
//sys	munmap(addr uintptr, length uintptr) (err error)
//sys	accept4(fd int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (nfd int, err error)

//sys	Unlinkat(dirfd int, path string, flags int) (err error)
//sys	Unmount(path string, flags int) (err error)
//sys	write(fd int, p []byte) (n int, err error)
//sys	mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error)
//sys	munmap(addr uintptr, length uintptr) (err error)
//sys	getfsstat(stat *Statfs_t, bufsize uintptr, flags int) (n int, err error)

func Madvise(b []byte, advice int) (err error) {
	return
}

func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
	return mapper.Mmap(fd, offset, length, prot, flags)
}

func Munmap(b []byte) (err error) {
	return mapper.Munmap(b)
}

//sys   Gethostname(buf []byte) (err error) = SYS___GETHOSTNAME_A
//sysnb	Getgid() (gid int)