jcs.org
qemu with hax to log dma reads & writes
jcs.org/2018/11/12/vfio
1#!/usr/bin/env python3
2#
3# Low-level QEMU shell on top of QMP.
4#
5# Copyright (C) 2009, 2010 Red Hat Inc.
6#
7# Authors:
8# Luiz Capitulino <lcapitulino@redhat.com>
9#
10# This work is licensed under the terms of the GNU GPL, version 2. See
11# the COPYING file in the top-level directory.
12#
13# Usage:
14#
15# Start QEMU with:
16#
17# # qemu [...] -qmp unix:./qmp-sock,server
18#
19# Run the shell:
20#
21# $ qmp-shell ./qmp-sock
22#
23# Commands have the following format:
24#
25# < command-name > [ arg-name1=arg1 ] ... [ arg-nameN=argN ]
26#
27# For example:
28#
29# (QEMU) device_add driver=e1000 id=net1
30# {u'return': {}}
31# (QEMU)
32#
33# key=value pairs also support Python or JSON object literal subset notations,
34# without spaces. Dictionaries/objects {} are supported as are arrays [].
35#
36# example-command arg-name1={'key':'value','obj'={'prop':"value"}}
37#
38# Both JSON and Python formatting should work, including both styles of
39# string literal quotes. Both paradigms of literal values should work,
40# including null/true/false for JSON and None/True/False for Python.
41#
42#
43# Transactions have the following multi-line format:
44#
45# transaction(
46# action-name1 [ arg-name1=arg1 ] ... [arg-nameN=argN ]
47# ...
48# action-nameN [ arg-name1=arg1 ] ... [arg-nameN=argN ]
49# )
50#
51# One line transactions are also supported:
52#
53# transaction( action-name1 ... )
54#
55# For example:
56#
57# (QEMU) transaction(
58# TRANS> block-dirty-bitmap-add node=drive0 name=bitmap1
59# TRANS> block-dirty-bitmap-clear node=drive0 name=bitmap0
60# TRANS> )
61# {"return": {}}
62# (QEMU)
63#
64# Use the -v and -p options to activate the verbose and pretty-print options,
65# which will echo back the properly formatted JSON-compliant QMP that is being
66# sent to QEMU, which is useful for debugging and documentation generation.
67
68import json
69import ast
70import readline
71import sys
72import os
73import errno
74import atexit
75import re
76
77sys.path.append(os.path.join(os.path.dirname(__file__), '..', '..', 'python'))
78from qemu import qmp
79
80if sys.version_info[0] == 2:
81 input = raw_input
82
83class QMPCompleter(list):
84 def complete(self, text, state):
85 for cmd in self:
86 if cmd.startswith(text):
87 if not state:
88 return cmd
89 else:
90 state -= 1
91
92class QMPShellError(Exception):
93 pass
94
95class QMPShellBadPort(QMPShellError):
96 pass
97
98class FuzzyJSON(ast.NodeTransformer):
99 '''This extension of ast.NodeTransformer filters literal "true/false/null"
100 values in an AST and replaces them by proper "True/False/None" values that
101 Python can properly evaluate.'''
102 def visit_Name(self, node):
103 if node.id == 'true':
104 node.id = 'True'
105 if node.id == 'false':
106 node.id = 'False'
107 if node.id == 'null':
108 node.id = 'None'
109 return node
110
111# TODO: QMPShell's interface is a bit ugly (eg. _fill_completion() and
112# _execute_cmd()). Let's design a better one.
113class QMPShell(qmp.QEMUMonitorProtocol):
114 def __init__(self, address, pretty=False):
115 super(QMPShell, self).__init__(self.__get_address(address))
116 self._greeting = None
117 self._completer = None
118 self._pretty = pretty
119 self._transmode = False
120 self._actions = list()
121 self._histfile = os.path.join(os.path.expanduser('~'),
122 '.qmp-shell_history')
123
124 def __get_address(self, arg):
125 """
126 Figure out if the argument is in the port:host form, if it's not it's
127 probably a file path.
128 """
129 addr = arg.split(':')
130 if len(addr) == 2:
131 try:
132 port = int(addr[1])
133 except ValueError:
134 raise QMPShellBadPort
135 return ( addr[0], port )
136 # socket path
137 return arg
138
139 def _fill_completion(self):
140 cmds = self.cmd('query-commands')
141 if 'error' in cmds:
142 return
143 for cmd in cmds['return']:
144 self._completer.append(cmd['name'])
145
146 def __completer_setup(self):
147 self._completer = QMPCompleter()
148 self._fill_completion()
149 readline.set_history_length(1024)
150 readline.set_completer(self._completer.complete)
151 readline.parse_and_bind("tab: complete")
152 # XXX: default delimiters conflict with some command names (eg. query-),
153 # clearing everything as it doesn't seem to matter
154 readline.set_completer_delims('')
155 try:
156 readline.read_history_file(self._histfile)
157 except Exception as e:
158 if isinstance(e, IOError) and e.errno == errno.ENOENT:
159 # File not found. No problem.
160 pass
161 else:
162 print("Failed to read history '%s'; %s" % (self._histfile, e))
163 atexit.register(self.__save_history)
164
165 def __save_history(self):
166 try:
167 readline.write_history_file(self._histfile)
168 except Exception as e:
169 print("Failed to save history file '%s'; %s" % (self._histfile, e))
170
171 def __parse_value(self, val):
172 try:
173 return int(val)
174 except ValueError:
175 pass
176
177 if val.lower() == 'true':
178 return True
179 if val.lower() == 'false':
180 return False
181 if val.startswith(('{', '[')):
182 # Try first as pure JSON:
183 try:
184 return json.loads(val)
185 except ValueError:
186 pass
187 # Try once again as FuzzyJSON:
188 try:
189 st = ast.parse(val, mode='eval')
190 return ast.literal_eval(FuzzyJSON().visit(st))
191 except SyntaxError:
192 pass
193 except ValueError:
194 pass
195 return val
196
197 def __cli_expr(self, tokens, parent):
198 for arg in tokens:
199 (key, sep, val) = arg.partition('=')
200 if sep != '=':
201 raise QMPShellError("Expected a key=value pair, got '%s'" % arg)
202
203 value = self.__parse_value(val)
204 optpath = key.split('.')
205 curpath = []
206 for p in optpath[:-1]:
207 curpath.append(p)
208 d = parent.get(p, {})
209 if type(d) is not dict:
210 raise QMPShellError('Cannot use "%s" as both leaf and non-leaf key' % '.'.join(curpath))
211 parent[p] = d
212 parent = d
213 if optpath[-1] in parent:
214 if type(parent[optpath[-1]]) is dict:
215 raise QMPShellError('Cannot use "%s" as both leaf and non-leaf key' % '.'.join(curpath))
216 else:
217 raise QMPShellError('Cannot set "%s" multiple times' % key)
218 parent[optpath[-1]] = value
219
220 def __build_cmd(self, cmdline):
221 """
222 Build a QMP input object from a user provided command-line in the
223 following format:
224
225 < command-name > [ arg-name1=arg1 ] ... [ arg-nameN=argN ]
226 """
227 cmdargs = re.findall(r'''(?:[^\s"']|"(?:\\.|[^"])*"|'(?:\\.|[^'])*')+''', cmdline)
228
229 # Transactional CLI entry/exit:
230 if cmdargs[0] == 'transaction(':
231 self._transmode = True
232 cmdargs.pop(0)
233 elif cmdargs[0] == ')' and self._transmode:
234 self._transmode = False
235 if len(cmdargs) > 1:
236 raise QMPShellError("Unexpected input after close of Transaction sub-shell")
237 qmpcmd = { 'execute': 'transaction',
238 'arguments': { 'actions': self._actions } }
239 self._actions = list()
240 return qmpcmd
241
242 # Nothing to process?
243 if not cmdargs:
244 return None
245
246 # Parse and then cache this Transactional Action
247 if self._transmode:
248 finalize = False
249 action = { 'type': cmdargs[0], 'data': {} }
250 if cmdargs[-1] == ')':
251 cmdargs.pop(-1)
252 finalize = True
253 self.__cli_expr(cmdargs[1:], action['data'])
254 self._actions.append(action)
255 return self.__build_cmd(')') if finalize else None
256
257 # Standard command: parse and return it to be executed.
258 qmpcmd = { 'execute': cmdargs[0], 'arguments': {} }
259 self.__cli_expr(cmdargs[1:], qmpcmd['arguments'])
260 return qmpcmd
261
262 def _print(self, qmp):
263 indent = None
264 if self._pretty:
265 indent = 4
266 jsobj = json.dumps(qmp, indent=indent)
267 print(str(jsobj))
268
269 def _execute_cmd(self, cmdline):
270 try:
271 qmpcmd = self.__build_cmd(cmdline)
272 except Exception as e:
273 print('Error while parsing command line: %s' % e)
274 print('command format: <command-name> ', end=' ')
275 print('[arg-name1=arg1] ... [arg-nameN=argN]')
276 return True
277 # For transaction mode, we may have just cached the action:
278 if qmpcmd is None:
279 return True
280 if self._verbose:
281 self._print(qmpcmd)
282 resp = self.cmd_obj(qmpcmd)
283 if resp is None:
284 print('Disconnected')
285 return False
286 self._print(resp)
287 return True
288
289 def connect(self, negotiate):
290 self._greeting = super(QMPShell, self).connect(negotiate)
291 self.__completer_setup()
292
293 def show_banner(self, msg='Welcome to the QMP low-level shell!'):
294 print(msg)
295 if not self._greeting:
296 print('Connected')
297 return
298 version = self._greeting['QMP']['version']['qemu']
299 print('Connected to QEMU %d.%d.%d\n' % (version['major'],version['minor'],version['micro']))
300
301 def get_prompt(self):
302 if self._transmode:
303 return "TRANS> "
304 return "(QEMU) "
305
306 def read_exec_command(self, prompt):
307 """
308 Read and execute a command.
309
310 @return True if execution was ok, return False if disconnected.
311 """
312 try:
313 cmdline = input(prompt)
314 except EOFError:
315 print()
316 return False
317 if cmdline == '':
318 for ev in self.get_events():
319 print(ev)
320 self.clear_events()
321 return True
322 else:
323 return self._execute_cmd(cmdline)
324
325 def set_verbosity(self, verbose):
326 self._verbose = verbose
327
328class HMPShell(QMPShell):
329 def __init__(self, address):
330 QMPShell.__init__(self, address)
331 self.__cpu_index = 0
332
333 def __cmd_completion(self):
334 for cmd in self.__cmd_passthrough('help')['return'].split('\r\n'):
335 if cmd and cmd[0] != '[' and cmd[0] != '\t':
336 name = cmd.split()[0] # drop help text
337 if name == 'info':
338 continue
339 if name.find('|') != -1:
340 # Command in the form 'foobar|f' or 'f|foobar', take the
341 # full name
342 opt = name.split('|')
343 if len(opt[0]) == 1:
344 name = opt[1]
345 else:
346 name = opt[0]
347 self._completer.append(name)
348 self._completer.append('help ' + name) # help completion
349
350 def __info_completion(self):
351 for cmd in self.__cmd_passthrough('info')['return'].split('\r\n'):
352 if cmd:
353 self._completer.append('info ' + cmd.split()[1])
354
355 def __other_completion(self):
356 # special cases
357 self._completer.append('help info')
358
359 def _fill_completion(self):
360 self.__cmd_completion()
361 self.__info_completion()
362 self.__other_completion()
363
364 def __cmd_passthrough(self, cmdline, cpu_index = 0):
365 return self.cmd_obj({ 'execute': 'human-monitor-command', 'arguments':
366 { 'command-line': cmdline,
367 'cpu-index': cpu_index } })
368
369 def _execute_cmd(self, cmdline):
370 if cmdline.split()[0] == "cpu":
371 # trap the cpu command, it requires special setting
372 try:
373 idx = int(cmdline.split()[1])
374 if not 'return' in self.__cmd_passthrough('info version', idx):
375 print('bad CPU index')
376 return True
377 self.__cpu_index = idx
378 except ValueError:
379 print('cpu command takes an integer argument')
380 return True
381 resp = self.__cmd_passthrough(cmdline, self.__cpu_index)
382 if resp is None:
383 print('Disconnected')
384 return False
385 assert 'return' in resp or 'error' in resp
386 if 'return' in resp:
387 # Success
388 if len(resp['return']) > 0:
389 print(resp['return'], end=' ')
390 else:
391 # Error
392 print('%s: %s' % (resp['error']['class'], resp['error']['desc']))
393 return True
394
395 def show_banner(self):
396 QMPShell.show_banner(self, msg='Welcome to the HMP shell!')
397
398def die(msg):
399 sys.stderr.write('ERROR: %s\n' % msg)
400 sys.exit(1)
401
402def fail_cmdline(option=None):
403 if option:
404 sys.stderr.write('ERROR: bad command-line option \'%s\'\n' % option)
405 sys.stderr.write('qmp-shell [ -v ] [ -p ] [ -H ] [ -N ] < UNIX socket path> | < TCP address:port >\n')
406 sys.stderr.write(' -v Verbose (echo command sent and received)\n')
407 sys.stderr.write(' -p Pretty-print JSON\n')
408 sys.stderr.write(' -H Use HMP interface\n')
409 sys.stderr.write(' -N Skip negotiate (for qemu-ga)\n')
410 sys.exit(1)
411
412def main():
413 addr = ''
414 qemu = None
415 hmp = False
416 pretty = False
417 verbose = False
418 negotiate = True
419
420 try:
421 for arg in sys.argv[1:]:
422 if arg == "-H":
423 if qemu is not None:
424 fail_cmdline(arg)
425 hmp = True
426 elif arg == "-p":
427 pretty = True
428 elif arg == "-N":
429 negotiate = False
430 elif arg == "-v":
431 verbose = True
432 else:
433 if qemu is not None:
434 fail_cmdline(arg)
435 if hmp:
436 qemu = HMPShell(arg)
437 else:
438 qemu = QMPShell(arg, pretty)
439 addr = arg
440
441 if qemu is None:
442 fail_cmdline()
443 except QMPShellBadPort:
444 die('bad port number in command-line')
445
446 try:
447 qemu.connect(negotiate)
448 except qmp.QMPConnectError:
449 die('Didn\'t get QMP greeting message')
450 except qmp.QMPCapabilitiesError:
451 die('Could not negotiate capabilities')
452 except qemu.error:
453 die('Could not connect to %s' % addr)
454
455 qemu.show_banner()
456 qemu.set_verbosity(verbose)
457 while qemu.read_exec_command(qemu.get_prompt()):
458 pass
459 qemu.close()
460
461if __name__ == '__main__':
462 main()