[PATCH v1 07/14] tests/vm: Add configuration to basevm.py

[Robert Foley <robert.foley@linaro.org>]

Added use of a configuration to tests/vm/basevm.py.
The configuration provides parameters used to configure a VM.
This allows for providing alternate configurations to the VM being
created/launched. cpu, machine, memory, and NUMA configuration are all
examples of configuration which we might want to vary on the VM being created
or launched.
This will for example allow for creating an aarch64 vm.

Signed-off-by: Robert Foley <robert.foley@linaro.org>
---
 tests/vm/basevm.py | 141 +++++++++++++++++++++++++++++++++++----------
 1 file changed, 111 insertions(+), 30 deletions(-)

diff --git a/tests/vm/basevm.py b/tests/vm/basevm.py
index 87a484c55c..33004934af 100755
--- a/tests/vm/basevm.py
+++ b/tests/vm/basevm.py
@@ -33,19 +33,43 @@ import multiprocessing
 import traceback
 from socket_thread import SocketThread
 
-SSH_KEY = open(os.path.join(os.path.dirname(__file__),
-               "..", "keys", "id_rsa")).read()
-SSH_PUB_KEY = open(os.path.join(os.path.dirname(__file__),
-                   "..", "keys", "id_rsa.pub")).read()
+SSH_KEY_FILE = os.path.join(os.path.dirname(__file__),
+               "..", "keys", "id_rsa")
+SSH_PUB_KEY_FILE = os.path.join(os.path.dirname(__file__),
+                   "..", "keys", "id_rsa.pub")
 
 class ConsoleTimeoutException(Exception):
     """Raise this exception when read from console times out."""
     pass
 
+# This is the standard configuration.
+# Any or all of these can be overridden by
+# passing in a config argument to the VM constructor.
+DEFAULT_CONFIG = {
+    'cpu'             : "max",
+    'machine'         : 'pc',
+    'guest_user'      : "qemu",
+    'guest_pass'      : "qemupass",
+    'root_pass'       : "qemupass",
+    'ssh_key_file'    : SSH_KEY_FILE,
+    'ssh_pub_key_file': SSH_PUB_KEY_FILE,
+    'memory'          : "4G",
+    'extra_args'      : [],
+    'qemu_args'       : "",
+    'dns'             : "",
+    'ssh_port'        : 0,
+    'install_cmds'    : "",
+    'boot_dev_type'   : "block",
+    'ssh_timeout'     : 1,
+}
+BOOT_DEVICE = {
+    'block' :  "-drive file={},if=none,id=drive0,cache=writeback "\
+               "-device virtio-blk,drive=drive0,bootindex=0",
+    'scsi'  :  "-device virtio-scsi-device,id=scsi "\
+               "-drive file={},format=raw,if=none,id=hd0 "\
+               "-device scsi-hd,drive=hd0,bootindex=0",
+}
 class BaseVM(object):
-    GUEST_USER = "qemu"
-    GUEST_PASS = "qemupass"
-    ROOT_PASS = "qemupass"
 
     envvars = [
         "https_proxy",
@@ -71,22 +95,33 @@ class BaseVM(object):
     # since we found we need to wait more than twice as long.
     tcg_ssh_timeout_multiplier = 4
     console_logfile = "console.log"
-    def __init__(self, debug=False, vcpus=None):
+    def __init__(self, debug=False, vcpus=None, config=None):
         self._guest = None
         self._console_fd = None
         self._socket_thread = None
         self._console_timeout_sec = self.socket_timeout
+        # Allow input config to override defaults.
+        self._config = DEFAULT_CONFIG.copy()
+        if config != None:
+            self._config.update(config)
+        self.validate_ssh_keys()
         self._tmpdir = os.path.realpath(tempfile.mkdtemp(prefix="vm-test-",
                                                          suffix=".tmp",
                                                          dir="."))
         atexit.register(shutil.rmtree, self._tmpdir)
-
-        self._ssh_key_file = os.path.join(self._tmpdir, "id_rsa")
-        open(self._ssh_key_file, "w").write(SSH_KEY)
-        subprocess.check_call(["chmod", "600", self._ssh_key_file])
-
-        self._ssh_pub_key_file = os.path.join(self._tmpdir, "id_rsa.pub")
-        open(self._ssh_pub_key_file, "w").write(SSH_PUB_KEY)
+        # Copy the key files to a temporary directory.
+        # Also chmod the key file to agree with ssh requirements.
+        self._config['ssh_key'] = \
+            open(self._config['ssh_key_file']).read().rstrip()
+        self._config['ssh_pub_key'] = \
+            open(self._config['ssh_pub_key_file']).read().rstrip()
+        self._ssh_tmp_key_file = os.path.join(self._tmpdir, "id_rsa")
+        open(self._ssh_tmp_key_file, "w").write(self._config['ssh_key'])
+        subprocess.check_call(["chmod", "600", self._ssh_tmp_key_file])
+
+        self._ssh_tmp_pub_key_file = os.path.join(self._tmpdir, "id_rsa.pub")
+        open(self._ssh_tmp_pub_key_file,
+             "w").write(self._config['ssh_pub_key'])
 
         self.debug = debug
         self._stderr = sys.stderr
@@ -95,11 +130,14 @@ class BaseVM(object):
             self._stdout = sys.stdout
         else:
             self._stdout = self._devnull
+        netdev = "user,id=vnet,hostfwd=:127.0.0.1:{}-:22"
         self._args = [ \
-            "-nodefaults", "-m", "4G",
-            "-cpu", "max",
-            "-netdev", "user,id=vnet,hostfwd=:127.0.0.1:0-:22" +
-                       (",ipv6=no" if not self.ipv6 else ""),
+            "-nodefaults", "-m", self._config['memory'],
+            "-cpu", self._config['cpu'],
+            "-netdev",
+            netdev.format(self._config['ssh_port']) +
+            (",ipv6=no" if not self.ipv6 else "") +
+            (",dns=" + self._config['dns'] if self._config['dns'] else ""),
             "-device", "virtio-net-pci,netdev=vnet",
             "-vnc", "127.0.0.1:0,to=20"]
         if vcpus and vcpus > 1:
@@ -110,6 +148,45 @@ class BaseVM(object):
             logging.info("KVM not available, not using -enable-kvm")
         self._data_args = []
 
+        if self._config['qemu_args'] != None:
+            qemu_args = self._config['qemu_args']
+            qemu_args = qemu_args.replace('\n',' ').replace('\r','')
+            # Remove any empty strings from list.
+            self._config['extra_args'] = [x for x in qemu_args.split(' ') if x]
+
+    def validate_ssh_keys(self):
+        """Check to see if the ssh key files exist."""
+        if 'ssh_key_file' not in self._config or\
+           not os.path.exists(self._config['ssh_key_file']):
+            raise Exception("ssh key file not found.")
+        if 'ssh_pub_key_file' not in self._config or\
+           not os.path.exists(self._config['ssh_pub_key_file']):
+               raise Exception("ssh pub key file not found.")
+
+    def wait_boot(self, wait_string=None):
+        """Wait for the standard string we expect
+           on completion of a normal boot.
+           The user can also choose to override with an
+           alternate string to wait for."""
+        if wait_string is None:
+            if self.login_prompt is None:
+                raise Exception("self.login_prompt not defined")
+            wait_string = self.login_prompt
+        # Intentionally bump up the default timeout under TCG,
+        # since the console wait below takes longer.
+        timeout = self.socket_timeout
+        if not kvm_available(self.arch):
+            timeout *= 8
+        self.console_init(timeout=timeout)
+        self.console_wait(wait_string)
+
+    def __getattr__(self, name):
+        # Support direct access to config by key.
+        # for example, access self._config['cpu'] by self.cpu
+        if name.lower() in self._config.keys():
+            return self._config[name.lower()]
+        return object.__getattribute__(self, name)
+
     def _download_with_cache(self, url, sha256sum=None, sha512sum=None):
         def check_sha256sum(fname):
             if not sha256sum:
@@ -141,8 +218,9 @@ class BaseVM(object):
                    "-t",
                    "-o", "StrictHostKeyChecking=no",
                    "-o", "UserKnownHostsFile=" + os.devnull,
-                   "-o", "ConnectTimeout=1",
-                   "-p", self.ssh_port, "-i", self._ssh_key_file]
+                   "-o",
+                   "ConnectTimeout={}".format(self._config["ssh_timeout"]),
+                   "-p", self.ssh_port, "-i", self._ssh_tmp_key_file]
         # If not in debug mode, set ssh to quiet mode to
         # avoid printing the results of commands.
         if not self.debug:
@@ -200,15 +278,15 @@ class BaseVM(object):
         print("console logfile is: {}".format(self.console_logfile))
 
     def boot(self, img, extra_args=[]):
-        args = self._args + [
-            "-device", "VGA",
-            "-drive", "file=%s,if=none,id=drive0,cache=writeback" % img,
-            "-device", "virtio-blk,drive=drive0,bootindex=0"]
-        args += self._data_args + extra_args
+        boot_dev = BOOT_DEVICE[self._config['boot_dev_type']]
+        boot_params = boot_dev.format(img)
+        args = self._args + boot_params.split(' ')
+        args += self._data_args + extra_args + self._config['extra_args']
+        args += ["-device", "VGA"]
         logging.debug("QEMU args: %s", " ".join(args))
         qemu_bin = os.environ.get("QEMU", "qemu-system-" + self.arch)
         guest = QEMUMachine(binary=qemu_bin, args=args)
-        guest.set_machine('pc')
+        guest.set_machine(self._config['machine'])
         guest.set_console()
         try:
             guest.launch()
@@ -332,7 +410,8 @@ class BaseVM(object):
         self.console_send(command)
 
     def console_ssh_init(self, prompt, user, pw):
-        sshkey_cmd = "echo '%s' > .ssh/authorized_keys\n" % SSH_PUB_KEY.rstrip()
+        sshkey_cmd = "echo '%s' > .ssh/authorized_keys\n" \
+                     % self._config['ssh_pub_key'].rstrip()
         self.console_wait_send("login:",    "%s\n" % user)
         self.console_wait_send("Password:", "%s\n" % pw)
         self.console_wait_send(prompt,      "mkdir .ssh\n")
@@ -461,15 +540,17 @@ def parse_args(vmcls):
     parser.disable_interspersed_args()
     return parser.parse_args()
 
-def main(vmcls):
+def main(vmcls, config=None):
     try:
+        if config == None:
+            config = {}
         args, argv = parse_args(vmcls)
         if not argv and not args.build_qemu and not args.build_image:
             print("Nothing to do?")
             return 1
         logging.basicConfig(level=(logging.DEBUG if args.debug
                                    else logging.WARN))
-        vm = vmcls(debug=args.debug, vcpus=args.jobs)
+        vm = vmcls(debug=args.debug, vcpus=args.jobs, config=config)
         if args.build_image:
             if os.path.exists(args.image) and not args.force:
                 sys.stderr.writelines(["Image file exists: %s\n" % args.image,
-- 
2.17.1