Commit | Line | Data |
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c5df1839 | 1 | ;;; GNU Guix --- Functional package management for GNU |
b41c7beb | 2 | ;;; Copyright © 2013, 2014, 2015, 2016, 2017, 2018, 2019 Ludovic Courtès <ludo@gnu.org> |
2ef4d273 | 3 | ;;; Copyright © 2020 Jakub Kądziołka <kuba@kadziolka.net> |
fa35fb58 | 4 | ;;; Copyright © 2020 Maxim Cournoyer <maxim.cournoyer@gmail.com> |
c5df1839 LC |
5 | ;;; |
6 | ;;; This file is part of GNU Guix. | |
7 | ;;; | |
8 | ;;; GNU Guix is free software; you can redistribute it and/or modify it | |
9 | ;;; under the terms of the GNU General Public License as published by | |
10 | ;;; the Free Software Foundation; either version 3 of the License, or (at | |
11 | ;;; your option) any later version. | |
12 | ;;; | |
13 | ;;; GNU Guix is distributed in the hope that it will be useful, but | |
14 | ;;; WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | ;;; GNU General Public License for more details. | |
17 | ;;; | |
18 | ;;; You should have received a copy of the GNU General Public License | |
19 | ;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>. | |
20 | ||
21 | (define-module (gnu system file-systems) | |
575b4b09 | 22 | #:use-module (ice-9 match) |
9976c76a | 23 | #:use-module (rnrs bytevectors) |
7597478e | 24 | #:use-module (srfi srfi-1) |
b460ba79 | 25 | #:use-module (srfi srfi-2) |
a5acc17a | 26 | #:use-module (srfi srfi-9) |
b460ba79 MC |
27 | #:use-module (srfi srfi-26) |
28 | #:use-module (srfi srfi-35) | |
a5acc17a | 29 | #:use-module (srfi srfi-9 gnu) |
c5df1839 | 30 | #:use-module (guix records) |
9b336338 | 31 | #:use-module (gnu system uuid) |
47cef4ec LC |
32 | #:re-export (uuid ;backward compatibility |
33 | string->uuid | |
f8865db6 | 34 | uuid->string) |
a48d3450 | 35 | #:export (file-system |
c5df1839 LC |
36 | file-system? |
37 | file-system-device | |
99e676db | 38 | file-system-device->string |
a5acc17a | 39 | file-system-title ;deprecated |
c5df1839 LC |
40 | file-system-mount-point |
41 | file-system-type | |
42 | file-system-needed-for-boot? | |
43 | file-system-flags | |
44 | file-system-options | |
fa35fb58 MC |
45 | file-system-options->alist |
46 | alist->file-system-options | |
47 | ||
be21979d | 48 | file-system-mount? |
4e469051 LC |
49 | file-system-check? |
50 | file-system-create-mount-point? | |
e51710d1 | 51 | file-system-dependencies |
dd41a7f8 | 52 | file-system-location |
c5df1839 | 53 | |
278d486b | 54 | file-system-type-predicate |
b460ba79 MC |
55 | btrfs-subvolume? |
56 | btrfs-store-subvolume-file-name | |
278d486b | 57 | |
a5acc17a LC |
58 | file-system-label |
59 | file-system-label? | |
60 | file-system-label->string | |
61 | ||
575b4b09 | 62 | file-system->spec |
5970e8e2 | 63 | spec->file-system |
d77a0bd6 | 64 | specification->file-system-mapping |
575b4b09 | 65 | |
6ddb5960 | 66 | %pseudo-file-system-types |
c5df1839 | 67 | %fuse-control-file-system |
a69576ea | 68 | %binary-format-file-system |
705f8b68 MW |
69 | %shared-memory-file-system |
70 | %pseudo-terminal-file-system | |
3c185b24 | 71 | %tty-gid |
3392ce5d | 72 | %immutable-store |
727636aa | 73 | %control-groups |
14454f0b | 74 | %elogind-file-systems |
a69576ea | 75 | |
5dae0186 | 76 | %base-file-systems |
c829bc80 | 77 | %container-file-systems |
5dae0186 | 78 | |
9110c2e9 DT |
79 | <file-system-mapping> |
80 | file-system-mapping | |
81 | file-system-mapping? | |
82 | file-system-mapping-source | |
83 | file-system-mapping-target | |
84 | file-system-mapping-writable? | |
85 | ||
d2a5e698 LC |
86 | file-system-mapping->bind-mount |
87 | ||
7597478e LC |
88 | %store-mapping |
89 | %network-configuration-files | |
90 | %network-file-mappings)) | |
c5df1839 LC |
91 | |
92 | ;;; Commentary: | |
93 | ;;; | |
94 | ;;; Declaring file systems to be mounted. | |
95 | ;;; | |
278d486b LC |
96 | ;;; Note: this file system is used both in the Shepherd and on the "host |
97 | ;;; side", so it must not include (gnu packages …) modules. | |
98 | ;;; | |
c5df1839 LC |
99 | ;;; Code: |
100 | ||
101 | ;; File system declaration. | |
a5acc17a | 102 | (define-record-type* <file-system> %file-system |
c5df1839 LC |
103 | make-file-system |
104 | file-system? | |
a5acc17a | 105 | (device file-system-device) ; string | <uuid> | <file-system-label> |
c5df1839 LC |
106 | (mount-point file-system-mount-point) ; string |
107 | (type file-system-type) ; string | |
108 | (flags file-system-flags ; list of symbols | |
109 | (default '())) | |
110 | (options file-system-options ; string or #f | |
111 | (default #f)) | |
be21979d LC |
112 | (mount? file-system-mount? ; Boolean |
113 | (default #t)) | |
4d6b879c | 114 | (needed-for-boot? %file-system-needed-for-boot? ; Boolean |
c5df1839 LC |
115 | (default #f)) |
116 | (check? file-system-check? ; Boolean | |
4e469051 LC |
117 | (default #t)) |
118 | (create-mount-point? file-system-create-mount-point? ; Boolean | |
e51710d1 | 119 | (default #f)) |
e502bf89 | 120 | (dependencies file-system-dependencies ; list of <file-system> |
dd41a7f8 LC |
121 | (default '())) ; or <mapped-device> |
122 | (location file-system-location | |
123 | (default (current-source-location)) | |
124 | (innate))) | |
c5df1839 | 125 | |
a5acc17a LC |
126 | ;; A file system label for use in the 'device' field. |
127 | (define-record-type <file-system-label> | |
128 | (file-system-label label) | |
129 | file-system-label? | |
130 | (label file-system-label->string)) | |
131 | ||
132 | (set-record-type-printer! <file-system-label> | |
133 | (lambda (obj port) | |
134 | (format port "#<file-system-label ~s>" | |
135 | (file-system-label->string obj)))) | |
136 | ||
137 | (define-syntax report-deprecation | |
138 | (lambda (s) | |
139 | "Report the use of the now-deprecated 'title' field." | |
140 | (syntax-case s () | |
141 | ((_ field) | |
142 | (let* ((source (syntax-source #'field)) | |
143 | (file (and source (assq-ref source 'filename))) | |
144 | (line (and source | |
145 | (and=> (assq-ref source 'line) 1+))) | |
146 | (column (and source (assq-ref source 'column)))) | |
147 | (format (current-error-port) | |
148 | "~a:~a:~a: warning: 'title' field is deprecated~%" | |
149 | file line column) | |
150 | #t))))) | |
151 | ||
152 | ;; Helper for 'process-file-system-declaration'. | |
153 | (define-syntax device-expression | |
154 | (syntax-rules (quote label uuid device) | |
155 | ((_ (quote label) dev) | |
156 | (file-system-label dev)) | |
157 | ((_ (quote uuid) dev) | |
158 | (if (uuid? dev) dev (uuid dev))) | |
159 | ((_ (quote device) dev) | |
160 | dev) | |
161 | ((_ title dev) | |
162 | (case title | |
163 | ((label) (file-system-label dev)) | |
164 | ((uuid) (uuid dev)) | |
165 | (else dev))))) | |
166 | ||
167 | ;; Helper to interpret the now-deprecated 'title' field. Detect forms like | |
168 | ;; (title 'label), remove them, and adjust the 'device' field accordingly. | |
169 | ;; TODO: Remove this once 'title' has been deprecated long enough. | |
170 | (define-syntax process-file-system-declaration | |
171 | (syntax-rules (device title) | |
172 | ((_ () (rest ...) #f #f) ;no 'title' and no 'device' field | |
173 | (%file-system rest ...)) | |
174 | ((_ () (rest ...) dev #f) ;no 'title' field | |
175 | (%file-system rest ... (device dev))) | |
176 | ((_ () (rest ...) dev titl) ;got a 'title' field | |
177 | (%file-system rest ... | |
178 | (device (device-expression titl dev)))) | |
179 | ((_ ((title titl) rest ...) (previous ...) dev _) | |
180 | (begin | |
181 | (report-deprecation (title titl)) | |
182 | (process-file-system-declaration (rest ...) | |
183 | (previous ...) | |
184 | dev titl))) | |
185 | ((_ ((device dev) rest ...) (previous ...) _ titl) | |
186 | (process-file-system-declaration (rest ...) | |
187 | (previous ...) | |
188 | dev titl)) | |
189 | ((_ (field rest ...) (previous ...) dev titl) | |
190 | (process-file-system-declaration (rest ...) | |
191 | (previous ... field) | |
192 | dev titl)))) | |
193 | ||
194 | (define-syntax-rule (file-system fields ...) | |
195 | (process-file-system-declaration (fields ...) () #f #f)) | |
196 | ||
197 | (define (file-system-title fs) ;deprecated | |
198 | (match (file-system-device fs) | |
199 | ((? file-system-label?) 'label) | |
200 | ((? uuid?) 'uuid) | |
201 | ((? string?) 'device))) | |
202 | ||
ad167d02 LC |
203 | ;; Note: This module is used both on the build side and on the host side. |
204 | ;; Arrange not to pull (guix store) and (guix config) because the latter | |
205 | ;; differs from user to user. | |
206 | (define (%store-prefix) | |
207 | "Return the store prefix." | |
c45477d2 LC |
208 | ;; Note: If we have (guix store database) in the search path and we do *not* |
209 | ;; have (guix store) proper, 'resolve-module' returns an empty (guix store) | |
210 | ;; with one sub-module. | |
211 | (cond ((and=> (resolve-module '(guix store) #:ensure #f) | |
212 | (lambda (store) | |
213 | (module-variable store '%store-prefix))) | |
ad167d02 | 214 | => |
c45477d2 LC |
215 | (lambda (variable) |
216 | ((variable-ref variable)))) | |
ad167d02 LC |
217 | ((getenv "NIX_STORE") |
218 | => identity) | |
219 | (else | |
220 | "/gnu/store"))) | |
221 | ||
38434419 LC |
222 | (define %not-slash |
223 | (char-set-complement (char-set #\/))) | |
224 | ||
225 | (define (file-prefix? file1 file2) | |
226 | "Return #t if FILE1 denotes the name of a file that is a parent of FILE2, | |
227 | where both FILE1 and FILE2 are absolute file name. For example: | |
228 | ||
229 | (file-prefix? \"/gnu\" \"/gnu/store\") | |
230 | => #t | |
231 | ||
232 | (file-prefix? \"/gn\" \"/gnu/store\") | |
233 | => #f | |
234 | " | |
235 | (and (string-prefix? "/" file1) | |
236 | (string-prefix? "/" file2) | |
237 | (let loop ((file1 (string-tokenize file1 %not-slash)) | |
238 | (file2 (string-tokenize file2 %not-slash))) | |
239 | (match file1 | |
240 | (() | |
241 | #t) | |
242 | ((head1 tail1 ...) | |
243 | (match file2 | |
244 | ((head2 tail2 ...) | |
245 | (and (string=? head1 head2) (loop tail1 tail2))) | |
246 | (() | |
247 | #f))))))) | |
248 | ||
99e676db MC |
249 | (define* (file-system-device->string device #:key uuid-type) |
250 | "Return the string representations of the DEVICE field of a <file-system> | |
251 | record. When the device is a UUID, its representation is chosen depending on | |
252 | UUID-TYPE, a symbol such as 'dce or 'iso9660." | |
253 | (match device | |
254 | ((? file-system-label?) | |
255 | (file-system-label->string device)) | |
256 | ((? uuid?) | |
257 | (if uuid-type | |
258 | (uuid->string (uuid-bytevector device) uuid-type) | |
259 | (uuid->string device))) | |
260 | ((? string?) | |
261 | device))) | |
262 | ||
fa35fb58 MC |
263 | (define (file-system-options->alist string) |
264 | "Translate the option string format of a <file-system> record into an | |
265 | association list of options or option/value pairs." | |
266 | (if string | |
267 | (let ((options (string-split string #\,))) | |
268 | (map (lambda (param) | |
269 | (let ((=index (string-index param #\=))) | |
270 | (if =index | |
271 | (cons (string-take param =index) | |
272 | (string-drop param (1+ =index))) | |
273 | param))) | |
274 | options)) | |
275 | '())) | |
276 | ||
277 | (define (alist->file-system-options options) | |
278 | "Return the string representation of OPTIONS, an association list. The | |
279 | string obtained can be used as the option field of a <file-system> record." | |
280 | (if (null? options) | |
281 | #f | |
282 | (string-join (map (match-lambda | |
283 | ((key . value) | |
284 | (string-append key "=" value)) | |
285 | (key | |
286 | key)) | |
287 | options) | |
288 | ","))) | |
289 | ||
38434419 LC |
290 | (define (file-system-needed-for-boot? fs) |
291 | "Return true if FS has the 'needed-for-boot?' flag set, or if it holds the | |
292 | store--e.g., if FS is the root file system." | |
4d6b879c | 293 | (or (%file-system-needed-for-boot? fs) |
38434419 LC |
294 | (and (file-prefix? (file-system-mount-point fs) (%store-prefix)) |
295 | (not (memq 'bind-mount (file-system-flags fs)))))) | |
4d6b879c | 296 | |
575b4b09 DT |
297 | (define (file-system->spec fs) |
298 | "Return a list corresponding to file-system FS that can be passed to the | |
299 | initrd code." | |
300 | (match fs | |
a5acc17a LC |
301 | (($ <file-system> device mount-point type flags options _ _ check?) |
302 | (list (cond ((uuid? device) | |
303 | `(uuid ,(uuid-type device) ,(uuid-bytevector device))) | |
304 | ((file-system-label? device) | |
305 | `(file-system-label ,(file-system-label->string device))) | |
306 | (else device)) | |
307 | mount-point type flags options check?)))) | |
575b4b09 | 308 | |
5970e8e2 LC |
309 | (define (spec->file-system sexp) |
310 | "Deserialize SEXP, a list, to the corresponding <file-system> object." | |
311 | (match sexp | |
a5acc17a | 312 | ((device mount-point type flags options check?) |
5970e8e2 | 313 | (file-system |
9976c76a LC |
314 | (device (match device |
315 | (('uuid (? symbol? type) (? bytevector? bv)) | |
316 | (bytevector->uuid bv type)) | |
a5acc17a LC |
317 | (('file-system-label (? string? label)) |
318 | (file-system-label label)) | |
9976c76a LC |
319 | (_ |
320 | device))) | |
5970e8e2 LC |
321 | (mount-point mount-point) (type type) |
322 | (flags flags) (options options) | |
323 | (check? check?))))) | |
324 | ||
d77a0bd6 LC |
325 | (define (specification->file-system-mapping spec writable?) |
326 | "Read the SPEC and return the corresponding <file-system-mapping>. SPEC is | |
327 | a string of the form \"SOURCE\" or \"SOURCE=TARGET\". The former specifies | |
328 | that SOURCE from the host should be mounted at SOURCE in the other system. | |
329 | The latter format specifies that SOURCE from the host should be mounted at | |
330 | TARGET in the other system." | |
331 | (let ((index (string-index spec #\=))) | |
332 | (if index | |
333 | (file-system-mapping | |
334 | (source (substring spec 0 index)) | |
335 | (target (substring spec (+ 1 index))) | |
336 | (writable? writable?)) | |
337 | (file-system-mapping | |
338 | (source spec) | |
339 | (target spec) | |
340 | (writable? writable?))))) | |
341 | ||
661a1d79 LC |
342 | \f |
343 | ;;; | |
344 | ;;; Common file systems. | |
345 | ;;; | |
346 | ||
6ddb5960 LC |
347 | (define %pseudo-file-system-types |
348 | ;; List of know pseudo file system types. This is used when validating file | |
349 | ;; system definitions. | |
df1eaffc LC |
350 | '("binfmt_misc" "cgroup" "debugfs" "devpts" "devtmpfs" "efivarfs" "fusectl" |
351 | "hugetlbfs" "overlay" "proc" "securityfs" "sysfs" "tmpfs")) | |
6ddb5960 | 352 | |
c5df1839 LC |
353 | (define %fuse-control-file-system |
354 | ;; Control file system for Linux' file systems in user-space (FUSE). | |
355 | (file-system | |
356 | (device "fusectl") | |
357 | (mount-point "/sys/fs/fuse/connections") | |
358 | (type "fusectl") | |
359 | (check? #f))) | |
360 | ||
361 | (define %binary-format-file-system | |
362 | ;; Support for arbitrary executable binary format. | |
363 | (file-system | |
364 | (device "binfmt_misc") | |
365 | (mount-point "/proc/sys/fs/binfmt_misc") | |
366 | (type "binfmt_misc") | |
367 | (check? #f))) | |
368 | ||
7f239fd3 LC |
369 | (define %tty-gid |
370 | ;; ID of the 'tty' group. Allocate it statically to make it easy to refer | |
371 | ;; to it from here and from the 'tty' group definitions. | |
c8fa3426 | 372 | 996) |
7f239fd3 LC |
373 | |
374 | (define %pseudo-terminal-file-system | |
375 | ;; The pseudo-terminal file system. It needs to be mounted so that | |
376 | ;; statfs(2) returns DEVPTS_SUPER_MAGIC like libc's getpt(3) expects (and | |
377 | ;; thus openpty(3) and its users, such as xterm.) | |
378 | (file-system | |
379 | (device "none") | |
380 | (mount-point "/dev/pts") | |
381 | (type "devpts") | |
382 | (check? #f) | |
383 | (needed-for-boot? #f) | |
384 | (create-mount-point? #t) | |
385 | (options (string-append "gid=" (number->string %tty-gid) ",mode=620")))) | |
a69576ea | 386 | |
db17ae5c LC |
387 | (define %shared-memory-file-system |
388 | ;; Shared memory. | |
389 | (file-system | |
390 | (device "tmpfs") | |
391 | (mount-point "/dev/shm") | |
392 | (type "tmpfs") | |
393 | (check? #f) | |
394 | (flags '(no-suid no-dev)) | |
395 | (options "size=50%") ;TODO: make size configurable | |
396 | (create-mount-point? #t))) | |
397 | ||
3392ce5d LC |
398 | (define %immutable-store |
399 | ;; Read-only store to avoid users or daemons accidentally modifying it. | |
400 | ;; 'guix-daemon' has provisions to remount it read-write in its own name | |
401 | ;; space. | |
402 | (file-system | |
403 | (device (%store-prefix)) | |
404 | (mount-point (%store-prefix)) | |
405 | (type "none") | |
406 | (check? #f) | |
b41c7beb | 407 | (flags '(read-only bind-mount no-atime)))) |
3392ce5d | 408 | |
727636aa | 409 | (define %control-groups |
b78cad85 LC |
410 | (let ((parent (file-system |
411 | (device "cgroup") | |
412 | (mount-point "/sys/fs/cgroup") | |
413 | (type "tmpfs") | |
414 | (check? #f)))) | |
415 | (cons parent | |
416 | (map (lambda (subsystem) | |
417 | (file-system | |
418 | (device "cgroup") | |
419 | (mount-point (string-append "/sys/fs/cgroup/" subsystem)) | |
420 | (type "cgroup") | |
421 | (check? #f) | |
422 | (options subsystem) | |
423 | (create-mount-point? #t) | |
424 | ||
425 | ;; This must be mounted after, and unmounted before the | |
426 | ;; parent directory. | |
427 | (dependencies (list parent)))) | |
428 | '("cpuset" "cpu" "cpuacct" "memory" "devices" "freezer" | |
2ef4d273 | 429 | "blkio" "perf_event" "pids"))))) |
727636aa | 430 | |
14454f0b MW |
431 | (define %elogind-file-systems |
432 | ;; We don't use systemd, but these file systems are needed for elogind, | |
433 | ;; which was extracted from systemd. | |
2cf5f4c1 MO |
434 | (append |
435 | (list (file-system | |
436 | (device "none") | |
437 | (mount-point "/run/systemd") | |
438 | (type "tmpfs") | |
439 | (check? #f) | |
440 | (flags '(no-suid no-dev no-exec)) | |
441 | (options "mode=0755") | |
442 | (create-mount-point? #t)) | |
443 | (file-system | |
444 | (device "none") | |
445 | (mount-point "/run/user") | |
446 | (type "tmpfs") | |
447 | (check? #f) | |
448 | (flags '(no-suid no-dev no-exec)) | |
449 | (options "mode=0755") | |
450 | (create-mount-point? #t)) | |
451 | ;; Elogind uses cgroups to organize processes, allowing it to map PIDs | |
452 | ;; to sessions. Elogind's cgroup hierarchy isn't associated with any | |
453 | ;; resource controller ("subsystem"). | |
454 | (file-system | |
455 | (device "cgroup") | |
456 | (mount-point "/sys/fs/cgroup/elogind") | |
457 | (type "cgroup") | |
458 | (check? #f) | |
459 | (options "none,name=elogind") | |
460 | (create-mount-point? #t) | |
461 | (dependencies (list (car %control-groups))))) | |
462 | %control-groups)) | |
14454f0b | 463 | |
a69576ea LC |
464 | (define %base-file-systems |
465 | ;; List of basic file systems to be mounted. Note that /proc and /sys are | |
466 | ;; currently mounted by the initrd. | |
2cf5f4c1 MO |
467 | (list %pseudo-terminal-file-system |
468 | %shared-memory-file-system | |
469 | %immutable-store)) | |
a69576ea | 470 | |
c829bc80 DT |
471 | ;; File systems for Linux containers differ from %base-file-systems in that |
472 | ;; they impose additional restrictions such as no-exec or need different | |
473 | ;; options to function properly. | |
474 | ;; | |
475 | ;; The file system flags and options conform to the libcontainer | |
476 | ;; specification: | |
477 | ;; https://github.com/docker/libcontainer/blob/master/SPEC.md#filesystem | |
478 | (define %container-file-systems | |
479 | (list | |
b57ec5f6 | 480 | ;; Pseudo-terminal file system. |
c829bc80 DT |
481 | (file-system |
482 | (device "none") | |
483 | (mount-point "/dev/pts") | |
484 | (type "devpts") | |
485 | (flags '(no-exec no-suid)) | |
486 | (needed-for-boot? #t) | |
487 | (create-mount-point? #t) | |
488 | (check? #f) | |
489 | (options "newinstance,ptmxmode=0666,mode=620")) | |
490 | ;; Shared memory file system. | |
491 | (file-system | |
492 | (device "tmpfs") | |
493 | (mount-point "/dev/shm") | |
494 | (type "tmpfs") | |
495 | (flags '(no-exec no-suid no-dev)) | |
496 | (options "mode=1777,size=65536k") | |
497 | (needed-for-boot? #t) | |
498 | (create-mount-point? #t) | |
499 | (check? #f)) | |
500 | ;; Message queue file system. | |
501 | (file-system | |
502 | (device "mqueue") | |
503 | (mount-point "/dev/mqueue") | |
504 | (type "mqueue") | |
505 | (flags '(no-exec no-suid no-dev)) | |
506 | (needed-for-boot? #t) | |
507 | (create-mount-point? #t) | |
508 | (check? #f)))) | |
509 | ||
9110c2e9 DT |
510 | \f |
511 | ;;; | |
512 | ;;; Shared file systems, for VMs/containers. | |
513 | ;;; | |
514 | ||
515 | ;; Mapping of host file system SOURCE to mount point TARGET in the guest. | |
516 | (define-record-type* <file-system-mapping> file-system-mapping | |
517 | make-file-system-mapping | |
518 | file-system-mapping? | |
519 | (source file-system-mapping-source) ;string | |
520 | (target file-system-mapping-target) ;string | |
521 | (writable? file-system-mapping-writable? ;Boolean | |
522 | (default #f))) | |
523 | ||
d2a5e698 LC |
524 | (define (file-system-mapping->bind-mount mapping) |
525 | "Return a file system that realizes MAPPING, a <file-system-mapping>, using | |
526 | a bind mount." | |
527 | (match mapping | |
528 | (($ <file-system-mapping> source target writable?) | |
529 | (file-system | |
530 | (mount-point target) | |
531 | (device source) | |
532 | (type "none") | |
533 | (flags (if writable? | |
534 | '(bind-mount) | |
535 | '(bind-mount read-only))) | |
536 | (check? #f) | |
537 | (create-mount-point? #t))))) | |
538 | ||
9110c2e9 DT |
539 | (define %store-mapping |
540 | ;; Mapping of the host's store into the guest. | |
541 | (file-system-mapping | |
542 | (source (%store-prefix)) | |
543 | (target (%store-prefix)) | |
544 | (writable? #f))) | |
545 | ||
7597478e LC |
546 | (define %network-configuration-files |
547 | ;; List of essential network configuration files. | |
548 | '("/etc/resolv.conf" | |
549 | "/etc/nsswitch.conf" | |
550 | "/etc/services" | |
551 | "/etc/hosts")) | |
552 | ||
553 | (define %network-file-mappings | |
554 | ;; List of file mappings for essential network files. | |
555 | (filter-map (lambda (file) | |
556 | (file-system-mapping | |
557 | (source file) | |
558 | (target file) | |
559 | ;; XXX: On some GNU/Linux systems, /etc/resolv.conf is a | |
560 | ;; symlink to a file in a tmpfs which, for an unknown reason, | |
561 | ;; cannot be bind mounted read-only within the container. | |
625bdf09 LC |
562 | ;; The same goes with /var/run/nscd, as discussed in |
563 | ;; <https://bugs.gnu.org/37967>. | |
564 | (writable? (or (string=? file "/etc/resolv.conf") | |
565 | (string=? file "/var/run/nscd"))))) | |
5ccec771 | 566 | (cons "/var/run/nscd" %network-configuration-files))) |
7597478e | 567 | |
72089954 | 568 | (define (file-system-type-predicate type) |
7dbd75b3 LC |
569 | "Return a predicate that, when passed a file system, returns #t if that file |
570 | system has the given TYPE." | |
72089954 DM |
571 | (lambda (fs) |
572 | (string=? (file-system-type fs) type))) | |
573 | ||
b460ba79 MC |
574 | \f |
575 | ;;; | |
576 | ;;; Btrfs specific helpers. | |
577 | ;;; | |
578 | ||
579 | (define (btrfs-subvolume? fs) | |
580 | "Predicate to check if FS, a file-system object, is a Btrfs subvolume." | |
581 | (and-let* ((btrfs-file-system? (string= "btrfs" (file-system-type fs))) | |
582 | (option-keys (map (match-lambda | |
583 | ((key . value) key) | |
584 | (key key)) | |
585 | (file-system-options->alist | |
586 | (file-system-options fs))))) | |
587 | (find (cut string-prefix? "subvol" <>) option-keys))) | |
588 | ||
589 | (define (btrfs-store-subvolume-file-name file-systems) | |
590 | "Return the subvolume file name within the Btrfs top level onto which the | |
591 | store is located, else #f." | |
592 | ||
593 | (define (prepend-slash/maybe s) | |
594 | (if (string=? "/" (string-take s 1)) | |
595 | s | |
596 | (string-append "/" s))) | |
597 | ||
598 | (define (file-name-depth file-name) | |
599 | (length (string-tokenize file-name %not-slash))) | |
600 | ||
601 | (and-let* ((btrfs-subvolume-fs (filter btrfs-subvolume? file-systems)) | |
602 | (btrfs-subvolume-fs* | |
603 | (sort btrfs-subvolume-fs | |
604 | (lambda (fs1 fs2) | |
605 | (> (file-name-depth (file-system-mount-point fs1)) | |
606 | (file-name-depth (file-system-mount-point fs2)))))) | |
607 | (store-subvolume-fs | |
608 | (find (lambda (fs) (file-prefix? (file-system-mount-point fs) | |
609 | (%store-prefix))) | |
610 | btrfs-subvolume-fs*)) | |
611 | (options (file-system-options->alist | |
612 | (file-system-options store-subvolume-fs)))) | |
613 | ;; XXX: Deriving the subvolume name based from a subvolume ID is not | |
614 | ;; supported, as we'd need to query the actual file system. | |
615 | (or (and=> (assoc-ref options "subvol") prepend-slash/maybe) | |
616 | ;; FIXME: Use &fix-hint once it no longer pulls in (guix utils). | |
617 | (raise (condition | |
618 | (&message | |
619 | (message "The store is on a Btrfs subvolume, but the \ | |
620 | subvolume name is unknown. | |
621 | Hint: Use the \"subvol\" Btrfs file system option."))))))) | |
622 | ||
623 | ||
c5df1839 | 624 | ;;; file-systems.scm ends here |