xref: /qemu/scripts/analyze-migration.py (revision 310b3fe9)
1#!/usr/bin/env python
2#
3#  Migration Stream Analyzer
4#
5#  Copyright (c) 2015 Alexander Graf <agraf@suse.de>
6#
7# This library is free software; you can redistribute it and/or
8# modify it under the terms of the GNU Lesser General Public
9# License as published by the Free Software Foundation; either
10# version 2 of the License, or (at your option) any later version.
11#
12# This library is distributed in the hope that it will be useful,
13# but WITHOUT ANY WARRANTY; without even the implied warranty of
14# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15# Lesser General Public License for more details.
16#
17# You should have received a copy of the GNU Lesser General Public
18# License along with this library; if not, see <http://www.gnu.org/licenses/>.
19
20from __future__ import print_function
21import numpy as np
22import json
23import os
24import argparse
25import collections
26
27def mkdir_p(path):
28    try:
29        os.makedirs(path)
30    except OSError:
31        pass
32
33class MigrationFile(object):
34    def __init__(self, filename):
35        self.filename = filename
36        self.file = open(self.filename, "rb")
37
38    def read64(self):
39        return np.asscalar(np.fromfile(self.file, count=1, dtype='>i8')[0])
40
41    def read32(self):
42        return np.asscalar(np.fromfile(self.file, count=1, dtype='>i4')[0])
43
44    def read16(self):
45        return np.asscalar(np.fromfile(self.file, count=1, dtype='>i2')[0])
46
47    def read8(self):
48        return np.asscalar(np.fromfile(self.file, count=1, dtype='>i1')[0])
49
50    def readstr(self, len = None):
51        if len is None:
52            len = self.read8()
53        if len == 0:
54            return ""
55        return np.fromfile(self.file, count=1, dtype=('S%d' % len))[0]
56
57    def readvar(self, size = None):
58        if size is None:
59            size = self.read8()
60        if size == 0:
61            return ""
62        value = self.file.read(size)
63        if len(value) != size:
64            raise Exception("Unexpected end of %s at 0x%x" % (self.filename, self.file.tell()))
65        return value
66
67    def tell(self):
68        return self.file.tell()
69
70    # The VMSD description is at the end of the file, after EOF. Look for
71    # the last NULL byte, then for the beginning brace of JSON.
72    def read_migration_debug_json(self):
73        QEMU_VM_VMDESCRIPTION = 0x06
74
75        # Remember the offset in the file when we started
76        entrypos = self.file.tell()
77
78        # Read the last 10MB
79        self.file.seek(0, os.SEEK_END)
80        endpos = self.file.tell()
81        self.file.seek(max(-endpos, -10 * 1024 * 1024), os.SEEK_END)
82        datapos = self.file.tell()
83        data = self.file.read()
84        # The full file read closed the file as well, reopen it
85        self.file = open(self.filename, "rb")
86
87        # Find the last NULL byte, then the first brace after that. This should
88        # be the beginning of our JSON data.
89        nulpos = data.rfind("\0")
90        jsonpos = data.find("{", nulpos)
91
92        # Check backwards from there and see whether we guessed right
93        self.file.seek(datapos + jsonpos - 5, 0)
94        if self.read8() != QEMU_VM_VMDESCRIPTION:
95            raise Exception("No Debug Migration device found")
96
97        jsonlen = self.read32()
98
99        # Seek back to where we were at the beginning
100        self.file.seek(entrypos, 0)
101
102        return data[jsonpos:jsonpos + jsonlen]
103
104    def close(self):
105        self.file.close()
106
107class RamSection(object):
108    RAM_SAVE_FLAG_COMPRESS = 0x02
109    RAM_SAVE_FLAG_MEM_SIZE = 0x04
110    RAM_SAVE_FLAG_PAGE     = 0x08
111    RAM_SAVE_FLAG_EOS      = 0x10
112    RAM_SAVE_FLAG_CONTINUE = 0x20
113    RAM_SAVE_FLAG_XBZRLE   = 0x40
114    RAM_SAVE_FLAG_HOOK     = 0x80
115
116    def __init__(self, file, version_id, ramargs, section_key):
117        if version_id != 4:
118            raise Exception("Unknown RAM version %d" % version_id)
119
120        self.file = file
121        self.section_key = section_key
122        self.TARGET_PAGE_SIZE = ramargs['page_size']
123        self.dump_memory = ramargs['dump_memory']
124        self.write_memory = ramargs['write_memory']
125        self.sizeinfo = collections.OrderedDict()
126        self.data = collections.OrderedDict()
127        self.data['section sizes'] = self.sizeinfo
128        self.name = ''
129        if self.write_memory:
130            self.files = { }
131        if self.dump_memory:
132            self.memory = collections.OrderedDict()
133            self.data['memory'] = self.memory
134
135    def __repr__(self):
136        return self.data.__repr__()
137
138    def __str__(self):
139        return self.data.__str__()
140
141    def getDict(self):
142        return self.data
143
144    def read(self):
145        # Read all RAM sections
146        while True:
147            addr = self.file.read64()
148            flags = addr & (self.TARGET_PAGE_SIZE - 1)
149            addr &= ~(self.TARGET_PAGE_SIZE - 1)
150
151            if flags & self.RAM_SAVE_FLAG_MEM_SIZE:
152                while True:
153                    namelen = self.file.read8()
154                    # We assume that no RAM chunk is big enough to ever
155                    # hit the first byte of the address, so when we see
156                    # a zero here we know it has to be an address, not the
157                    # length of the next block.
158                    if namelen == 0:
159                        self.file.file.seek(-1, 1)
160                        break
161                    self.name = self.file.readstr(len = namelen)
162                    len = self.file.read64()
163                    self.sizeinfo[self.name] = '0x%016x' % len
164                    if self.write_memory:
165                        print(self.name)
166                        mkdir_p('./' + os.path.dirname(self.name))
167                        f = open('./' + self.name, "wb")
168                        f.truncate(0)
169                        f.truncate(len)
170                        self.files[self.name] = f
171                flags &= ~self.RAM_SAVE_FLAG_MEM_SIZE
172
173            if flags & self.RAM_SAVE_FLAG_COMPRESS:
174                if flags & self.RAM_SAVE_FLAG_CONTINUE:
175                    flags &= ~self.RAM_SAVE_FLAG_CONTINUE
176                else:
177                    self.name = self.file.readstr()
178                fill_char = self.file.read8()
179                # The page in question is filled with fill_char now
180                if self.write_memory and fill_char != 0:
181                    self.files[self.name].seek(addr, os.SEEK_SET)
182                    self.files[self.name].write(chr(fill_char) * self.TARGET_PAGE_SIZE)
183                if self.dump_memory:
184                    self.memory['%s (0x%016x)' % (self.name, addr)] = 'Filled with 0x%02x' % fill_char
185                flags &= ~self.RAM_SAVE_FLAG_COMPRESS
186            elif flags & self.RAM_SAVE_FLAG_PAGE:
187                if flags & self.RAM_SAVE_FLAG_CONTINUE:
188                    flags &= ~self.RAM_SAVE_FLAG_CONTINUE
189                else:
190                    self.name = self.file.readstr()
191
192                if self.write_memory or self.dump_memory:
193                    data = self.file.readvar(size = self.TARGET_PAGE_SIZE)
194                else: # Just skip RAM data
195                    self.file.file.seek(self.TARGET_PAGE_SIZE, 1)
196
197                if self.write_memory:
198                    self.files[self.name].seek(addr, os.SEEK_SET)
199                    self.files[self.name].write(data)
200                if self.dump_memory:
201                    hexdata = " ".join("{0:02x}".format(ord(c)) for c in data)
202                    self.memory['%s (0x%016x)' % (self.name, addr)] = hexdata
203
204                flags &= ~self.RAM_SAVE_FLAG_PAGE
205            elif flags & self.RAM_SAVE_FLAG_XBZRLE:
206                raise Exception("XBZRLE RAM compression is not supported yet")
207            elif flags & self.RAM_SAVE_FLAG_HOOK:
208                raise Exception("RAM hooks don't make sense with files")
209
210            # End of RAM section
211            if flags & self.RAM_SAVE_FLAG_EOS:
212                break
213
214            if flags != 0:
215                raise Exception("Unknown RAM flags: %x" % flags)
216
217    def __del__(self):
218        if self.write_memory:
219            for key in self.files:
220                self.files[key].close()
221
222
223class HTABSection(object):
224    HASH_PTE_SIZE_64       = 16
225
226    def __init__(self, file, version_id, device, section_key):
227        if version_id != 1:
228            raise Exception("Unknown HTAB version %d" % version_id)
229
230        self.file = file
231        self.section_key = section_key
232
233    def read(self):
234
235        header = self.file.read32()
236
237        if (header == -1):
238            # "no HPT" encoding
239            return
240
241        if (header > 0):
242            # First section, just the hash shift
243            return
244
245        # Read until end marker
246        while True:
247            index = self.file.read32()
248            n_valid = self.file.read16()
249            n_invalid = self.file.read16()
250
251            if index == 0 and n_valid == 0 and n_invalid == 0:
252                break
253
254            self.file.readvar(n_valid * self.HASH_PTE_SIZE_64)
255
256    def getDict(self):
257        return ""
258
259
260class ConfigurationSection(object):
261    def __init__(self, file):
262        self.file = file
263
264    def read(self):
265        name_len = self.file.read32()
266        name = self.file.readstr(len = name_len)
267
268class VMSDFieldGeneric(object):
269    def __init__(self, desc, file):
270        self.file = file
271        self.desc = desc
272        self.data = ""
273
274    def __repr__(self):
275        return str(self.__str__())
276
277    def __str__(self):
278        return " ".join("{0:02x}".format(ord(c)) for c in self.data)
279
280    def getDict(self):
281        return self.__str__()
282
283    def read(self):
284        size = int(self.desc['size'])
285        self.data = self.file.readvar(size)
286        return self.data
287
288class VMSDFieldInt(VMSDFieldGeneric):
289    def __init__(self, desc, file):
290        super(VMSDFieldInt, self).__init__(desc, file)
291        self.size = int(desc['size'])
292        self.format = '0x%%0%dx' % (self.size * 2)
293        self.sdtype = '>i%d' % self.size
294        self.udtype = '>u%d' % self.size
295
296    def __repr__(self):
297        if self.data < 0:
298            return ('%s (%d)' % ((self.format % self.udata), self.data))
299        else:
300            return self.format % self.data
301
302    def __str__(self):
303        return self.__repr__()
304
305    def getDict(self):
306        return self.__str__()
307
308    def read(self):
309        super(VMSDFieldInt, self).read()
310        self.sdata = np.fromstring(self.data, count=1, dtype=(self.sdtype))[0]
311        self.udata = np.fromstring(self.data, count=1, dtype=(self.udtype))[0]
312        self.data = self.sdata
313        return self.data
314
315class VMSDFieldUInt(VMSDFieldInt):
316    def __init__(self, desc, file):
317        super(VMSDFieldUInt, self).__init__(desc, file)
318
319    def read(self):
320        super(VMSDFieldUInt, self).read()
321        self.data = self.udata
322        return self.data
323
324class VMSDFieldIntLE(VMSDFieldInt):
325    def __init__(self, desc, file):
326        super(VMSDFieldIntLE, self).__init__(desc, file)
327        self.dtype = '<i%d' % self.size
328
329class VMSDFieldBool(VMSDFieldGeneric):
330    def __init__(self, desc, file):
331        super(VMSDFieldBool, self).__init__(desc, file)
332
333    def __repr__(self):
334        return self.data.__repr__()
335
336    def __str__(self):
337        return self.data.__str__()
338
339    def getDict(self):
340        return self.data
341
342    def read(self):
343        super(VMSDFieldBool, self).read()
344        if self.data[0] == 0:
345            self.data = False
346        else:
347            self.data = True
348        return self.data
349
350class VMSDFieldStruct(VMSDFieldGeneric):
351    QEMU_VM_SUBSECTION    = 0x05
352
353    def __init__(self, desc, file):
354        super(VMSDFieldStruct, self).__init__(desc, file)
355        self.data = collections.OrderedDict()
356
357        # When we see compressed array elements, unfold them here
358        new_fields = []
359        for field in self.desc['struct']['fields']:
360            if not 'array_len' in field:
361                new_fields.append(field)
362                continue
363            array_len = field.pop('array_len')
364            field['index'] = 0
365            new_fields.append(field)
366            for i in xrange(1, array_len):
367                c = field.copy()
368                c['index'] = i
369                new_fields.append(c)
370
371        self.desc['struct']['fields'] = new_fields
372
373    def __repr__(self):
374        return self.data.__repr__()
375
376    def __str__(self):
377        return self.data.__str__()
378
379    def read(self):
380        for field in self.desc['struct']['fields']:
381            try:
382                reader = vmsd_field_readers[field['type']]
383            except:
384                reader = VMSDFieldGeneric
385
386            field['data'] = reader(field, self.file)
387            field['data'].read()
388
389            if 'index' in field:
390                if field['name'] not in self.data:
391                    self.data[field['name']] = []
392                a = self.data[field['name']]
393                if len(a) != int(field['index']):
394                    raise Exception("internal index of data field unmatched (%d/%d)" % (len(a), int(field['index'])))
395                a.append(field['data'])
396            else:
397                self.data[field['name']] = field['data']
398
399        if 'subsections' in self.desc['struct']:
400            for subsection in self.desc['struct']['subsections']:
401                if self.file.read8() != self.QEMU_VM_SUBSECTION:
402                    raise Exception("Subsection %s not found at offset %x" % ( subsection['vmsd_name'], self.file.tell()))
403                name = self.file.readstr()
404                version_id = self.file.read32()
405                self.data[name] = VMSDSection(self.file, version_id, subsection, (name, 0))
406                self.data[name].read()
407
408    def getDictItem(self, value):
409       # Strings would fall into the array category, treat
410       # them specially
411       if value.__class__ is ''.__class__:
412           return value
413
414       try:
415           return self.getDictOrderedDict(value)
416       except:
417           try:
418               return self.getDictArray(value)
419           except:
420               try:
421                   return value.getDict()
422               except:
423                   return value
424
425    def getDictArray(self, array):
426        r = []
427        for value in array:
428           r.append(self.getDictItem(value))
429        return r
430
431    def getDictOrderedDict(self, dict):
432        r = collections.OrderedDict()
433        for (key, value) in dict.items():
434            r[key] = self.getDictItem(value)
435        return r
436
437    def getDict(self):
438        return self.getDictOrderedDict(self.data)
439
440vmsd_field_readers = {
441    "bool" : VMSDFieldBool,
442    "int8" : VMSDFieldInt,
443    "int16" : VMSDFieldInt,
444    "int32" : VMSDFieldInt,
445    "int32 equal" : VMSDFieldInt,
446    "int32 le" : VMSDFieldIntLE,
447    "int64" : VMSDFieldInt,
448    "uint8" : VMSDFieldUInt,
449    "uint16" : VMSDFieldUInt,
450    "uint32" : VMSDFieldUInt,
451    "uint32 equal" : VMSDFieldUInt,
452    "uint64" : VMSDFieldUInt,
453    "int64 equal" : VMSDFieldInt,
454    "uint8 equal" : VMSDFieldInt,
455    "uint16 equal" : VMSDFieldInt,
456    "float64" : VMSDFieldGeneric,
457    "timer" : VMSDFieldGeneric,
458    "buffer" : VMSDFieldGeneric,
459    "unused_buffer" : VMSDFieldGeneric,
460    "bitmap" : VMSDFieldGeneric,
461    "struct" : VMSDFieldStruct,
462    "unknown" : VMSDFieldGeneric,
463}
464
465class VMSDSection(VMSDFieldStruct):
466    def __init__(self, file, version_id, device, section_key):
467        self.file = file
468        self.data = ""
469        self.vmsd_name = ""
470        self.section_key = section_key
471        desc = device
472        if 'vmsd_name' in device:
473            self.vmsd_name = device['vmsd_name']
474
475        # A section really is nothing but a FieldStruct :)
476        super(VMSDSection, self).__init__({ 'struct' : desc }, file)
477
478###############################################################################
479
480class MigrationDump(object):
481    QEMU_VM_FILE_MAGIC    = 0x5145564d
482    QEMU_VM_FILE_VERSION  = 0x00000003
483    QEMU_VM_EOF           = 0x00
484    QEMU_VM_SECTION_START = 0x01
485    QEMU_VM_SECTION_PART  = 0x02
486    QEMU_VM_SECTION_END   = 0x03
487    QEMU_VM_SECTION_FULL  = 0x04
488    QEMU_VM_SUBSECTION    = 0x05
489    QEMU_VM_VMDESCRIPTION = 0x06
490    QEMU_VM_CONFIGURATION = 0x07
491    QEMU_VM_SECTION_FOOTER= 0x7e
492
493    def __init__(self, filename):
494        self.section_classes = { ( 'ram', 0 ) : [ RamSection, None ],
495                                 ( 'spapr/htab', 0) : ( HTABSection, None ) }
496        self.filename = filename
497        self.vmsd_desc = None
498
499    def read(self, desc_only = False, dump_memory = False, write_memory = False):
500        # Read in the whole file
501        file = MigrationFile(self.filename)
502
503        # File magic
504        data = file.read32()
505        if data != self.QEMU_VM_FILE_MAGIC:
506            raise Exception("Invalid file magic %x" % data)
507
508        # Version (has to be v3)
509        data = file.read32()
510        if data != self.QEMU_VM_FILE_VERSION:
511            raise Exception("Invalid version number %d" % data)
512
513        self.load_vmsd_json(file)
514
515        # Read sections
516        self.sections = collections.OrderedDict()
517
518        if desc_only:
519            return
520
521        ramargs = {}
522        ramargs['page_size'] = self.vmsd_desc['page_size']
523        ramargs['dump_memory'] = dump_memory
524        ramargs['write_memory'] = write_memory
525        self.section_classes[('ram',0)][1] = ramargs
526
527        while True:
528            section_type = file.read8()
529            if section_type == self.QEMU_VM_EOF:
530                break
531            elif section_type == self.QEMU_VM_CONFIGURATION:
532                section = ConfigurationSection(file)
533                section.read()
534            elif section_type == self.QEMU_VM_SECTION_START or section_type == self.QEMU_VM_SECTION_FULL:
535                section_id = file.read32()
536                name = file.readstr()
537                instance_id = file.read32()
538                version_id = file.read32()
539                section_key = (name, instance_id)
540                classdesc = self.section_classes[section_key]
541                section = classdesc[0](file, version_id, classdesc[1], section_key)
542                self.sections[section_id] = section
543                section.read()
544            elif section_type == self.QEMU_VM_SECTION_PART or section_type == self.QEMU_VM_SECTION_END:
545                section_id = file.read32()
546                self.sections[section_id].read()
547            elif section_type == self.QEMU_VM_SECTION_FOOTER:
548                read_section_id = file.read32()
549                if read_section_id != section_id:
550                    raise Exception("Mismatched section footer: %x vs %x" % (read_section_id, section_id))
551            else:
552                raise Exception("Unknown section type: %d" % section_type)
553        file.close()
554
555    def load_vmsd_json(self, file):
556        vmsd_json = file.read_migration_debug_json()
557        self.vmsd_desc = json.loads(vmsd_json, object_pairs_hook=collections.OrderedDict)
558        for device in self.vmsd_desc['devices']:
559            key = (device['name'], device['instance_id'])
560            value = ( VMSDSection, device )
561            self.section_classes[key] = value
562
563    def getDict(self):
564        r = collections.OrderedDict()
565        for (key, value) in self.sections.items():
566           key = "%s (%d)" % ( value.section_key[0], key )
567           r[key] = value.getDict()
568        return r
569
570###############################################################################
571
572class JSONEncoder(json.JSONEncoder):
573    def default(self, o):
574        if isinstance(o, VMSDFieldGeneric):
575            return str(o)
576        return json.JSONEncoder.default(self, o)
577
578parser = argparse.ArgumentParser()
579parser.add_argument("-f", "--file", help='migration dump to read from', required=True)
580parser.add_argument("-m", "--memory", help='dump RAM contents as well', action='store_true')
581parser.add_argument("-d", "--dump", help='what to dump ("state" or "desc")', default='state')
582parser.add_argument("-x", "--extract", help='extract contents into individual files', action='store_true')
583args = parser.parse_args()
584
585jsonenc = JSONEncoder(indent=4, separators=(',', ': '))
586
587if args.extract:
588    dump = MigrationDump(args.file)
589
590    dump.read(desc_only = True)
591    print("desc.json")
592    f = open("desc.json", "wb")
593    f.truncate()
594    f.write(jsonenc.encode(dump.vmsd_desc))
595    f.close()
596
597    dump.read(write_memory = True)
598    dict = dump.getDict()
599    print("state.json")
600    f = open("state.json", "wb")
601    f.truncate()
602    f.write(jsonenc.encode(dict))
603    f.close()
604elif args.dump == "state":
605    dump = MigrationDump(args.file)
606    dump.read(dump_memory = args.memory)
607    dict = dump.getDict()
608    print(jsonenc.encode(dict))
609elif args.dump == "desc":
610    dump = MigrationDump(args.file)
611    dump.read(desc_only = True)
612    print(jsonenc.encode(dump.vmsd_desc))
613else:
614    raise Exception("Please specify either -x, -d state or -d dump")
615