From: Jacob Lifshay Date: Sun, 3 Dec 2023 08:49:08 +0000 (-0800) Subject: caller.py: implement a pile of syscalls X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=bdab409250730ae3de090031ed7cda8e2e5eaad4;p=openpower-isa.git caller.py: implement a pile of syscalls this implements read, mmap, mmap2, brk, openat, uname, and newuname. it also stubs out munmap, mprotect, and pkey_mprotect so programs don't crash cpython. --- diff --git a/src/openpower/decoder/isa/caller.py b/src/openpower/decoder/isa/caller.py index e32116b2..ab931317 100644 --- a/src/openpower/decoder/isa/caller.py +++ b/src/openpower/decoder/isa/caller.py @@ -17,6 +17,9 @@ from collections import namedtuple from copy import deepcopy from functools import wraps import os +import errno +import struct +from openpower.syscalls import ppc_flags import sys from elftools.elf.elffile import ELFFile # for isinstance @@ -1174,6 +1177,80 @@ class SyscallEmulator(openpower.syscalls.Dispatcher): except OSError as e: return -e.errno + def sys_read(self, fd, buf, count, *rest): + buf = self.__isacaller.mem.get_ctypes(buf, count, is_write=True) + try: + return os.readv(fd, [buf]) + except OSError as e: + return -e.errno + + def sys_mmap(self, addr, length, prot, flags, fd, offset, *rest): + return self.__isacaller.mem.mmap_syscall( + addr, length, prot, flags, fd, offset, is_mmap2=False) + + def sys_mmap2(self, addr, length, prot, flags, fd, offset, *rest): + return self.__isacaller.mem.mmap_syscall( + addr, length, prot, flags, fd, offset, is_mmap2=True) + + def sys_brk(self, addr, *rest): + return self.__isacaller.mem.brk_syscall(addr) + + def sys_munmap(self, addr, length, *rest): + return -errno.ENOSYS # TODO: implement + + def sys_mprotect(self, addr, length, prot, *rest): + return -errno.ENOSYS # TODO: implement + + def sys_pkey_mprotect(self, addr, length, prot, pkey, *rest): + return -errno.ENOSYS # TODO: implement + + def sys_openat(self, dirfd, pathname, flags, mode, *rest): + try: + path = self.__isacaller.mem.read_cstr(pathname) + except (ValueError, MemException): + return -errno.EFAULT + try: + if dirfd == ppc_flags.AT_FDCWD: + return os.open(path, flags, mode) + else: + return os.open(path, flags, mode, dir_fd=dirfd) + except OSError as e: + return -e.errno + + def _uname(self): + uname = os.uname() + sysname = b'Linux' + nodename = uname.nodename.encode() + release = b'5.6.0-1-powerpc64le' + version = b'#1 SMP Debian 5.6.7-1 (2020-04-29)' + machine = b'ppc64le' + domainname = b'' + return sysname, nodename, release, version, machine, domainname + + def sys_uname(self, buf, *rest): + s = struct.Struct("<65s65s65s65s65s") + try: + buf = self.__isacaller.mem.get_ctypes(buf, s.size, is_write=True) + except (ValueError, MemException): + return -errno.EFAULT + sysname, nodename, release, version, machine, domainname = \ + self._uname() + s.pack_into(buf, 0, sysname, nodename, release, version, machine) + return 0 + + def sys_newuname(self, buf, *rest): + name_len = ppc_flags.__NEW_UTS_LEN + 1 + s = struct.Struct("<%ds%ds%ds%ds%ds%ds" % ((name_len,) * 6)) + try: + buf = self.__isacaller.mem.get_ctypes(buf, s.size, is_write=True) + except (ValueError, MemException): + return -errno.EFAULT + sysname, nodename, release, version, machine, domainname = \ + self._uname() + s.pack_into(buf, 0, + sysname, nodename, release, version, machine, domainname) + return 0 + class ISACaller(ISACallerHelper, ISAFPHelpers, StepLoop): # decoder2 - an instance of power_decoder2 diff --git a/src/openpower/decoder/isa/mem.py b/src/openpower/decoder/isa/mem.py index a2a84c53..ddb3b886 100644 --- a/src/openpower/decoder/isa/mem.py +++ b/src/openpower/decoder/isa/mem.py @@ -301,6 +301,23 @@ class MemCommon: lines = "\n".join(lines) log(f"\n{name}:\n{lines}\n", kind=kind) + def read_cstr(self, addr): + """ returns a `bytearray` for the c string starting at addr, the + returned `bytearray` doesn't contain the nul terminator. + + modifying the returned `bytearray` doesn't modify bytes in `self` + -- it is a copy. + """ + retval = bytearray() + while True: + b = self.ld(addr, width=1) + if b: + retval.append(b) + addr += 1 + else: + break + return retval + class Mem(MemCommon): def __init__(self, row_bytes=8, initial_mem=None, misaligned_ok=False):