summaryrefslogtreecommitdiff
path: root/raidguessfs.py
blob: ffb0912eff85a4f948a7212ab5b4d5d98b34cc76 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
#!/usr/bin/env python

# RaidGuessFS, a FUSE pseudo-filesystem to guess RAID parameters of a damaged device
# Copyright (C) 2015 Ludovic Pouzenc <ludovic@pouzenc.fr>
#
# Inspired by various python-fuse examples :
#  hello.py
#    Copyright (C) 2006  Andrew Straw  <strawman@astraw.com>
#
#  nullfs.py
#    Copyright (C) 2001  Jeff Epler  <jepler@unpythonic.dhs.org>
#    Copyright (C) 2006  Csaba Henk  <csaba.henk@creo.hu>
#
#  templatefs.py
#    Copyright (c) 2009 Matt Giuca
#
# Since they use LGPL and BSD licence, I choose GPLv3 (seems okay)
# This file is part of RaidGuessFS.
#
# RaidGuessFS is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# RaidGuessFS is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with RaidGuessFS. If not, see <http://www.gnu.org/licenses/>

# Standard modules
import sys, os, errno, logging, re, fuse
# Custom modules
import mystat, mydisks, mybinview, myraid

if not hasattr(fuse, '__version__'):
    raise RuntimeError, \
        "your fuse-py doesn't know of fuse.__version__, probably it's too old."


class RaidGuessFS(fuse.Fuse):
    """Main class, implementing the actual pseudo-filesystem"""

    def __init__(self, *args, **kwargs):
        logging.info("Initializing filesystem")
        logging.debug("Enter RaidGuessFS.__init__()")
        super(RaidGuessFS,self).__init__(*args, **kwargs)

        # Early initialisations (notably the static directory tree part)
        self.d = mydisks.MyDisks()
        self.raid = myraid.MyRaid()
        self.bmp = mybinview.MyBinView()
        self.st = mystat.MyStat()

        self.bmp.refresh_bmp()

        self.dattr = { '/': self.st.make_fake_dir() }
        self.fattr = { '/fsinit_has_failed': self.st.make_fake_file(0) }

        self.settings = [
                'disk_count',
                'raid_start', 'raid_chunk_size', 'raid_disk_order',
                'bmp_height', 'bmp_width', 'bmp_start_offset'
                ]

        self.settings_getters = [
                self.d.get_disk_count,
                self.raid.get_raid_start, self.raid.get_raid_chunk_size, self.raid.get_raid_disk_order_str,
                self.bmp.get_bmp_height, self.bmp.get_bmp_width, self.bmp.get_bmp_start_offset
                ]

        self.settings_updaters = [
                self.update_disk_count,
                self.update_raid_start, self.update_raid_chunk_size, self.update_raid_disk_order,
                self.update_bmp_height, self.update_bmp_width, self.update_bmp_start_offset
                ]

        self.dentries = {
                '/'      : [ fuse.Direntry(name) for name in ['config','disk','raid','visual'] ],
                '/config': [ fuse.Direntry(name) for name in self.settings ],
                '/raid'  : [ fuse.Direntry(name) for name in self.raid.raid_types ],
                '/disk'  : [ ], # Filled in _refresh_disk_dentries()
                '/visual': [ ], # Filled in _refresh_disk_dentries()
        }
        
        for raid_type in self.raid.raid_types:
            self.dentries.update( {
                # TODO : all type of raid don't need the same pseudo files
                '/raid/%s'%raid_type: [ fuse.Direntry(name) for name in ['result','data_xor','parity'] ],
                }
                )
        logging.debug("Exit. RaidGuessFS.__init__()")

    def _refresh_disk_dentries(self):
        """Internal function to update directory entries about all disks"""
        logging.debug("Enter _refresh_disk_dentries()")
        disk_dentries = []
        visual_dentries = []
        for d in range(self.d.disk_count):
            st_img = self.st.make_fake_file(self.d.disks_size[d])
            st_bmp = self.st.make_fake_file(self.bmp.bmp_size)
            self.fattr.update( {
                '/disk/disk%02d.img'%d: st_img,
                '/visual/disk%02d.bmp'%d: st_bmp,
                    }
                ) 
            disk_dentries.append( fuse.Direntry('disk%02d.img'%d) )
            visual_dentries.append( fuse.Direntry('disk%02d.bmp'%d) )

        self.dentries.update( { '/disk': disk_dentries } )
        self.dentries.update( { '/visual': visual_dentries } )
        logging.debug("Exit. _refresh_disk_dentries()")

    def _refresh_raid_fattr(self):
        """Update the raid computed attributes after a config change"""
        logging.debug("Enter _refresh_raid_fattr()")

        for raid_type in self.raid.raid_types:
            self.fattr['/raid/%s/data_xor'%raid_type].st_size = 0 # self.raid.raid_size
            self.fattr['/raid/%s/parity'%raid_type].st_size = min(self.d.disks_size) / self.raid.raid_sector_size * 16
            self.fattr['/raid/%s/result'%raid_type].st_size = self.raid.raid_size

        logging.debug("Exit. _refresh_raid_fattr()")

    def _split_path(self,path):
        """Internal function to explode path for read() and write() calls"""
        m = re.match('/([^/]+)/([^./0-9]*)([0-9+]*)(\.[^/]+)?(?:/([^/]+))?$', path)
        if m:
            return m.groups()
        else:
            return []

    def update_disk_count(self,arg):
        i = int(arg)
        assert (i > 0), "Negative value make no sense here"
        self.d.set_disk_count(i)
        self.d.open_disks()
        self._refresh_disk_dentries()
        self.raid.set_raid_end(min(self.d.disks_size)-1)
        self.update_raid_disk_order(range(i))
        self._refresh_raid_fattr()

    def update_bmp_start_offset(self, arg):
        i = int(arg)
        assert (i >= 0), "Negative value make no sense here"
        self.bmp.set_bmp_start_offset(i)
        self.bmp.refresh_bmp()
        self._refresh_disk_dentries()

    def update_bmp_width(self, arg):
        i = int(arg)
        assert (i > 0), "Non-positive value make no sense here"
        self.bmp.set_bmp_width(i)
        self.bmp.refresh_bmp()
        self._refresh_disk_dentries()

    def update_bmp_height(self, arg):
        i = int(arg)
        assert (i > 0), "Non-positive value make no sense here"
        self.bmp.set_bmp_height(i)
        self.bmp.refresh_bmp()
        self._refresh_disk_dentries()

    def update_raid_start(self, arg):
        i = int(arg)
        assert (i >= 0), "Negative value make no sense here"
        self.raid.set_raid_start(i)
        self._refresh_raid_fattr()

    def update_raid_chunk_size(self, arg):
        i = int(arg)
        assert (i > 0), "Non-positive value make no sense here"
        self.raid.set_raid_chunk_size(i)

    def update_raid_disk_order(self, arg):
        logging.debug("Enter update_raid_disk_order(%s)"%arg)
        if type(arg) is str:
            l = arg.split()
        else:
            l = arg
        # TODO : sanity checks (every disk number below disk count, len(list) below disk count, no double...)
        logging.debug("==> %s (%d/%d)"%(l,len(l),self.d.disk_count))
        self.raid.set_raid_disk_order(l)
        logging.debug("Exit. update_raid_disk_order(%s)"%arg)


########################################################
# Actual File System operations implementation follows #
########################################################


    def fsinit(self):
        """Make some run-time initalisations after argument parsing"""
        logging.info("Mounting filesystem...")
        # WARNING : this method is called by FUSE in a context that don't show fatal exceptions,
        # even with -d[ebug] flag set, so log all exceptions stupidly
        try:
            self.dattr = {
                path: self.st.make_fake_dir() for path in self.dentries.keys()
            }
            self.fattr = {
                    '/config/%s'%s: self.st.make_fake_file(64,0666) for s in self.settings
                    }
            for raid_type in self.raid.raid_types:
                self.fattr.update( {
                    '/raid/%s/data_xor'%raid_type: self.st.make_fake_file(0),
                    '/raid/%s/parity'%raid_type: self.st.make_fake_file(0),
                    '/raid/%s/result'%raid_type: self.st.make_fake_file(0),
                })

            self.d.set_disks_path([getattr(self.parser.values,'disk%02d'%d) for d in range(self.d.max_disks)])
            self.update_disk_count(len(self.d.disk_paths))

            self._refresh_disk_dentries()
            self._refresh_raid_fattr()

            logging.info("Mounted.")
        except Exception as e:
            logging.error(e)
    
    def getattr(self, path):
        logging.info("getattr: %s" % path)
        res = self.dattr.get(path) or self.fattr.get(path) or -errno.ENOENT
        logging.debug("==> " + str(res))
        return res

    def fgetattr(self, path, fh=None):
        #logging.debug("fgetattr: %s (fh %s)" % (path, fh))
        return self.getattr(path)
    
    def readdir(self, path, offset, dh=None):
        logging.info("readdir: %s (offset %s, dh %s)" % (path, offset, dh))
        return self.dentries[path]

    def truncate(self, path, size):
        logging.info("truncate: %s (size %s)" % (path, size))
        if path.startswith('/config/'):
            return # Ignore truncates on pseudo config files
        else:
            return -errno.EOPNOTSUPP

    def ftruncate(self, path, size, fh=None):
        logging.info("ftruncate: %s (size %s, fh %s)" % (path, size, fh))
        return self.truncate(path, size)

    def read(self, path, size, offset, fh=None):
        logging.info("read: %s (size %s, offset %s, fh %s)" % (path, size, offset, fh))

        path_chuncks = self._split_path(path)
        if path_chuncks:
            try:
                if path_chuncks[0] == 'config':
                    # TODO take care here
                    idx = self.settings.index(path_chuncks[1])
                    return str(self.settings_getters[idx]()) + "\n"

                if path_chuncks[0] == 'disk':
                    if path_chuncks[1] == 'disk':
                        i = int(path_chuncks[2])
                        if 0 <= i <= self.d.disk_count:
                            if path_chuncks[3] == '.img':
                                return self.d.read(i,offset,size)
                            if path_chuncks[3] == '.bmp':
                                return self.bmp.read(self.d.disks[i],offset,size)

                if path_chuncks[0] == 'visual':
                    if path_chuncks[1] == 'disk':
                        i = int(path_chuncks[2])
                        if 0 <= i <= self.d.disk_count:
                            if path_chuncks[3] == '.bmp':
                                return self.bmp.read(self.d.disks[i],offset,size)

                if path_chuncks[0] == 'raid':
                    raid_type=path_chuncks[2]
                    if raid_type in self.raid.raid_types:
                        if path_chuncks[4] == 'result':
                            return self.raid.read_data(raid_type,self.d.disks,offset,size)
                        if path_chuncks[4] == 'parity':
                            return self.raid.check_data(raid_type,self.d.disks,offset,size)

            except Exception as e:
                logging.error(e)
                return -errno.ENOENT

        logging.error("Unimplemented read of '%s' (%s)"%(path, str(path_chuncks)))
        return -errno.ENOENT

    def write(self, path, buf, offset, fh=None):
        logging.info("write: %s (offset %s, fh %s)" % (path, offset, fh))

        path_chuncks = self._split_path(path)
        if path_chuncks:
            try:
                if path_chuncks[0] == 'config':
                    # TODO take care here
                    idx = self.settings.index(path_chuncks[1])
                    try:
                        self.settings_updaters[idx](buf)
                        return len(buf)
                    except Exception as e:
                        logging.error(e)
                        return -errno.EIO

            except Exception as e:
                logging.error(e)
                return -errno.ENOENT

        logging.error("Unimplemented write of '%s' (%s)"%(path, str(path_chuncks)))
        return -errno.ENOENT


def main():
    usage = fuse.Fuse.fusage + """

RaidGuessFS is a pseudo-filesystem that allows to guess parameters and disk order of a damaged RAID devices.
  Takes disk image files as arguments (defaults to ./diskNN.img).
  Could take advantage of ddrecue logs file (metadata about unreadable sectors)
"""
    fuse.fuse_python_api = (0, 2)

    LOG_FILENAME = "raidguessfs.log"
    logging.basicConfig(filename=LOG_FILENAME,level=logging.WARN,)
    #logging.basicConfig(filename=LOG_FILENAME,level=logging.INFO,)
    #logging.basicConfig(filename=LOG_FILENAME,level=logging.DEBUG,)

    server = RaidGuessFS(version="%prog " + fuse.__version__,usage=usage,dash_s_do='setsingle')
    server.multithreaded = False

    cwd = os.getcwd()
    for num in range(server.d.max_disks):
        server.parser.add_option(
                mountopt="disk%02d"%num,
                metavar="ABS_PATH",
                default="%s/disk%02d.img"%(cwd,num),
                help="Disk #%d image file path [default: ./disk%02d.img]"%(num,num)
        )
        server.parser.add_option(
                mountopt="logf%02d"%num,
                metavar="ABS_PATH",
                default="%s/disk%02d.log"%(cwd,num),
                help="Disk #%d ddrescue log file [default: ./disk%02d.log]"%(num,num)
        )

    server.parse(errex=1)
    server.main()

if __name__ == '__main__':
    main()