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Commit | Line | Data |
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10ee5932 | 1 | /* |
0f23ee0c KZ |
2 | * No copyright is claimed. This code is in the public domain; do with |
3 | * it what you wish. | |
4 | * | |
5 | * Written by Karel Zak <kzak@redhat.com> | |
10ee5932 KZ |
6 | * |
7 | * -- based on mount/losetup.c | |
8 | * | |
9 | * Simple library for work with loop devices. | |
10 | * | |
11 | * - requires kernel 2.6.x | |
12 | * - reads info from /sys/block/loop<N>/loop/<attr> (new kernels) | |
13 | * - reads info by ioctl | |
14 | * - supports *unlimited* number of loop devices | |
15 | * - supports /dev/loop<N> as well as /dev/loop/<N> | |
16 | * - minimize overhead (fd, loopinfo, ... are shared for all operations) | |
17 | * - setup (associate device and backing file) | |
18 | * - delete (dis-associate file) | |
19 | * - old LOOP_{SET,GET}_STATUS (32bit) ioctls are unsupported | |
20 | * - extendible | |
21 | */ | |
22 | #include <stdio.h> | |
23 | #include <stdint.h> | |
24 | #include <string.h> | |
25 | #include <ctype.h> | |
26 | #include <fcntl.h> | |
10ee5932 KZ |
27 | #include <stdlib.h> |
28 | #include <unistd.h> | |
29 | #include <sys/ioctl.h> | |
30 | #include <sys/stat.h> | |
31 | #include <sys/mman.h> | |
32 | #include <sys/sysmacros.h> | |
33 | #include <inttypes.h> | |
34 | #include <dirent.h> | |
35 | #include <linux/posix_types.h> | |
36 | ||
37 | #include "linux_version.h" | |
38 | #include "c.h" | |
39 | #include "sysfs.h" | |
40 | #include "pathnames.h" | |
41 | #include "loopdev.h" | |
42 | #include "canonicalize.h" | |
e4062c72 | 43 | #include "at.h" |
293714c0 | 44 | #include "blkdev.h" |
10ee5932 | 45 | |
aee31ddc KZ |
46 | #define CONFIG_LOOPDEV_DEBUG |
47 | ||
48 | #ifdef CONFIG_LOOPDEV_DEBUG | |
aee31ddc KZ |
49 | # include <stdarg.h> |
50 | ||
51 | # define DBG(l,x) do { \ | |
52 | if ((l)->debug) {\ | |
53 | fprintf(stderr, "loopdev: [%p]: ", (l)); \ | |
54 | x; \ | |
55 | } \ | |
56 | } while(0) | |
57 | ||
58 | static inline void __attribute__ ((__format__ (__printf__, 1, 2))) | |
59 | loopdev_debug(const char *mesg, ...) | |
60 | { | |
61 | va_list ap; | |
62 | va_start(ap, mesg); | |
63 | vfprintf(stderr, mesg, ap); | |
64 | va_end(ap); | |
65 | fputc('\n', stderr); | |
66 | } | |
67 | ||
68 | #else /* !CONFIG_LOOPDEV_DEBUG */ | |
69 | # define DBG(m,x) do { ; } while(0) | |
70 | #endif | |
71 | ||
e4062c72 KZ |
72 | /* |
73 | * see loopcxt_init() | |
74 | */ | |
10ee5932 | 75 | #define loopcxt_ioctl_enabled(_lc) (!((_lc)->flags & LOOPDEV_FL_NOIOCTL)) |
e4062c72 KZ |
76 | #define loopcxt_sysfs_available(_lc) (!((_lc)->flags & LOOPDEV_FL_NOSYSFS)) \ |
77 | && !loopcxt_ioctl_enabled(_lc) | |
10ee5932 KZ |
78 | |
79 | /* | |
80 | * @lc: context | |
81 | * @device: device name, absolute device path or NULL to reset the current setting | |
82 | * | |
83 | * Sets device, absolute paths (e.g. "/dev/loop<N>") are unchanged, device | |
84 | * names ("loop<N>") are converted to the path (/dev/loop<N> or to | |
85 | * /dev/loop/<N>) | |
86 | * | |
85794fb0 KZ |
87 | * This sets the device name, but does not check if the device exists! |
88 | * | |
10ee5932 KZ |
89 | * Returns: <0 on error, 0 on success |
90 | */ | |
91 | int loopcxt_set_device(struct loopdev_cxt *lc, const char *device) | |
92 | { | |
93 | if (!lc) | |
94 | return -EINVAL; | |
95 | ||
f4bf9592 | 96 | if (lc->fd >= 0) { |
10ee5932 | 97 | close(lc->fd); |
f4bf9592 KZ |
98 | DBG(lc, loopdev_debug("closing old open fd")); |
99 | } | |
10ee5932 | 100 | lc->fd = -1; |
fd7f0718 | 101 | lc->mode = 0; |
10ee5932 | 102 | lc->has_info = 0; |
6c224de1 | 103 | lc->info_failed = 0; |
10ee5932 | 104 | *lc->device = '\0'; |
fd7f0718 | 105 | memset(&lc->info, 0, sizeof(lc->info)); |
10ee5932 KZ |
106 | |
107 | /* set new */ | |
108 | if (device) { | |
109 | if (*device != '/') { | |
110 | const char *dir = _PATH_DEV; | |
111 | ||
112 | /* compose device name for /dev/loop<n> or /dev/loop/<n> */ | |
113 | if (lc->flags & LOOPDEV_FL_DEVSUBDIR) { | |
114 | if (strlen(device) < 5) | |
115 | return -1; | |
116 | device += 4; | |
117 | dir = _PATH_DEV_LOOP "/"; /* _PATH_DEV uses tailing slash */ | |
118 | } | |
119 | snprintf(lc->device, sizeof(lc->device), "%s%s", | |
120 | dir, device); | |
121 | } else { | |
122 | strncpy(lc->device, device, sizeof(lc->device)); | |
123 | lc->device[sizeof(lc->device) - 1] = '\0'; | |
124 | } | |
85794fb0 | 125 | DBG(lc, loopdev_debug("%s name assigned", device)); |
10ee5932 KZ |
126 | } |
127 | ||
128 | sysfs_deinit(&lc->sysfs); | |
129 | return 0; | |
130 | } | |
131 | ||
c7e0925d KZ |
132 | int loopcxt_has_device(struct loopdev_cxt *lc) |
133 | { | |
134 | return lc && *lc->device; | |
135 | } | |
136 | ||
10ee5932 KZ |
137 | /* |
138 | * @lc: context | |
139 | * @flags: LOOPDEV_FL_* flags | |
140 | * | |
141 | * Initilize loop handler. | |
142 | * | |
fd7f0718 KZ |
143 | * We have two sets of the flags: |
144 | * | |
145 | * * LOOPDEV_FL_* flags control loopcxt_* API behavior | |
146 | * | |
147 | * * LO_FLAGS_* are kernel flags used for LOOP_{SET,GET}_STAT64 ioctls | |
148 | * | |
149 | * Note about LOOPDEV_FL_{RDONLY,RDWR} flags. These flags are used for open(2) | |
150 | * syscall to open loop device. By default is the device open read-only. | |
151 | * | |
152 | * The expection is loopcxt_setup_device(), where the device is open read-write | |
153 | * if LO_FLAGS_READ_ONLY flags is not set (see loopcxt_set_flags()). | |
154 | * | |
10ee5932 KZ |
155 | * Returns: <0 on error, 0 on success. |
156 | */ | |
157 | int loopcxt_init(struct loopdev_cxt *lc, int flags) | |
158 | { | |
defa0710 | 159 | int rc; |
0b14bf7a | 160 | struct stat st; |
6219c25e | 161 | struct loopdev_cxt dummy = UL_LOOPDEVCXT_EMPTY; |
0b14bf7a | 162 | |
10ee5932 KZ |
163 | if (!lc) |
164 | return -EINVAL; | |
165 | ||
6219c25e | 166 | memcpy(lc, &dummy, sizeof(dummy)); |
10ee5932 | 167 | lc->flags = flags; |
defa0710 | 168 | |
f4bf9592 KZ |
169 | if (getenv("LOOPDEV_DEBUG")) |
170 | loopcxt_enable_debug(lc, TRUE); | |
171 | ||
defa0710 KZ |
172 | rc = loopcxt_set_device(lc, NULL); |
173 | if (rc) | |
174 | return rc; | |
10ee5932 | 175 | |
df0f2ad7 KZ |
176 | if (stat(_PATH_SYS_BLOCK, &st) || !S_ISDIR(st.st_mode)) { |
177 | lc->flags |= LOOPDEV_FL_NOSYSFS; | |
178 | lc->flags &= ~LOOPDEV_FL_NOIOCTL; | |
179 | DBG(lc, loopdev_debug("init: disable /sys usage")); | |
180 | } | |
181 | ||
82b4082e | 182 | if (!(lc->flags & LOOPDEV_FL_NOSYSFS) && |
f4bf9592 | 183 | get_linux_version() >= KERNEL_VERSION(2,6,37)) { |
10ee5932 KZ |
184 | /* |
185 | * Use only sysfs for basic information about loop devices | |
186 | */ | |
187 | lc->flags |= LOOPDEV_FL_NOIOCTL; | |
f4bf9592 KZ |
188 | DBG(lc, loopdev_debug("init: ignore ioctls")); |
189 | } | |
10ee5932 | 190 | |
f4bf9592 | 191 | if (!(lc->flags & LOOPDEV_FL_CONTROL) && !stat(_PATH_DEV_LOOPCTL, &st)) { |
0b14bf7a | 192 | lc->flags |= LOOPDEV_FL_CONTROL; |
f4bf9592 KZ |
193 | DBG(lc, loopdev_debug("init: loop-control detected ")); |
194 | } | |
0b14bf7a | 195 | |
10ee5932 KZ |
196 | return 0; |
197 | } | |
198 | ||
199 | /* | |
200 | * @lc: context | |
201 | * | |
202 | * Deinitialize loop context | |
203 | */ | |
204 | void loopcxt_deinit(struct loopdev_cxt *lc) | |
205 | { | |
82756a74 KZ |
206 | int errsv = errno; |
207 | ||
10ee5932 KZ |
208 | if (!lc) |
209 | return; | |
210 | ||
aee31ddc KZ |
211 | DBG(lc, loopdev_debug("de-initialize")); |
212 | ||
10ee5932 KZ |
213 | free(lc->filename); |
214 | lc->filename = NULL; | |
215 | ||
defa0710 | 216 | ignore_result( loopcxt_set_device(lc, NULL) ); |
10ee5932 | 217 | loopcxt_deinit_iterator(lc); |
82756a74 KZ |
218 | |
219 | errno = errsv; | |
10ee5932 KZ |
220 | } |
221 | ||
aee31ddc KZ |
222 | /* |
223 | * @lc: context | |
224 | * @enable: TRUE/FALSE | |
225 | * | |
226 | * Enabled/disables debug messages | |
227 | */ | |
228 | void loopcxt_enable_debug(struct loopdev_cxt *lc, int enable) | |
229 | { | |
230 | if (lc) | |
231 | lc->debug = enable ? 1 : 0; | |
232 | } | |
233 | ||
10ee5932 KZ |
234 | /* |
235 | * @lc: context | |
236 | * | |
237 | * Returns newly allocated device path. | |
238 | */ | |
239 | char *loopcxt_strdup_device(struct loopdev_cxt *lc) | |
240 | { | |
b481b622 | 241 | if (!lc || !lc->device || !*lc->device) |
10ee5932 KZ |
242 | return NULL; |
243 | return strdup(lc->device); | |
244 | } | |
245 | ||
246 | /* | |
247 | * @lc: context | |
248 | * | |
249 | * Returns pointer device name in the @lc struct. | |
250 | */ | |
251 | const char *loopcxt_get_device(struct loopdev_cxt *lc) | |
252 | { | |
b481b622 | 253 | return lc && lc->device && *lc->device ? lc->device : NULL; |
10ee5932 KZ |
254 | } |
255 | ||
256 | /* | |
257 | * @lc: context | |
258 | * | |
259 | * Returns pointer to the sysfs context (see lib/sysfs.c) | |
260 | */ | |
261 | struct sysfs_cxt *loopcxt_get_sysfs(struct loopdev_cxt *lc) | |
262 | { | |
263 | if (!lc || !*lc->device || (lc->flags & LOOPDEV_FL_NOSYSFS)) | |
264 | return NULL; | |
265 | ||
266 | if (!lc->sysfs.devno) { | |
267 | dev_t devno = sysfs_devname_to_devno(lc->device, NULL); | |
aee31ddc KZ |
268 | if (!devno) { |
269 | DBG(lc, loopdev_debug("sysfs: failed devname to devno")); | |
10ee5932 | 270 | return NULL; |
aee31ddc KZ |
271 | } |
272 | if (sysfs_init(&lc->sysfs, devno, NULL)) { | |
273 | DBG(lc, loopdev_debug("sysfs: init failed")); | |
10ee5932 | 274 | return NULL; |
aee31ddc | 275 | } |
10ee5932 | 276 | } |
aee31ddc | 277 | |
10ee5932 KZ |
278 | return &lc->sysfs; |
279 | } | |
280 | ||
281 | /* | |
282 | * @lc: context | |
283 | * | |
284 | * Returns: file descriptor to the open loop device or <0 on error. The mode | |
285 | * depends on LOOPDEV_FL_{RDWR,RDONLY} context flags. Default is | |
286 | * read-only. | |
287 | */ | |
288 | int loopcxt_get_fd(struct loopdev_cxt *lc) | |
289 | { | |
290 | if (!lc || !*lc->device) | |
fd7f0718 | 291 | return -EINVAL; |
10ee5932 | 292 | |
fd7f0718 KZ |
293 | if (lc->fd < 0) { |
294 | lc->mode = lc->flags & LOOPDEV_FL_RDWR ? O_RDWR : O_RDONLY; | |
b1fa3e22 | 295 | lc->fd = open(lc->device, lc->mode | O_CLOEXEC); |
663bf040 KZ |
296 | DBG(lc, loopdev_debug("open %s [%s]: %m", lc->device, |
297 | lc->flags & LOOPDEV_FL_RDWR ? "rw" : "ro")); | |
fd7f0718 | 298 | } |
10ee5932 KZ |
299 | return lc->fd; |
300 | } | |
301 | ||
fd7f0718 KZ |
302 | int loopcxt_set_fd(struct loopdev_cxt *lc, int fd, int mode) |
303 | { | |
304 | if (!lc) | |
305 | return -EINVAL; | |
306 | ||
307 | lc->fd = fd; | |
308 | lc->mode = mode; | |
309 | return 0; | |
310 | } | |
311 | ||
10ee5932 KZ |
312 | /* |
313 | * @lc: context | |
314 | * @flags: LOOPITER_FL_* flags | |
315 | * | |
316 | * Iterator allows to scan list of the free or used loop devices. | |
317 | * | |
318 | * Returns: <0 on error, 0 on success | |
319 | */ | |
320 | int loopcxt_init_iterator(struct loopdev_cxt *lc, int flags) | |
321 | { | |
322 | struct loopdev_iter *iter; | |
323 | struct stat st; | |
324 | ||
325 | if (!lc) | |
326 | return -EINVAL; | |
327 | ||
aee31ddc KZ |
328 | DBG(lc, loopdev_debug("iter: initialize")); |
329 | ||
10ee5932 KZ |
330 | iter = &lc->iter; |
331 | ||
332 | /* always zeroize | |
333 | */ | |
334 | memset(iter, 0, sizeof(*iter)); | |
335 | iter->ncur = -1; | |
336 | iter->flags = flags; | |
337 | iter->default_check = 1; | |
338 | ||
339 | if (!lc->extra_check) { | |
340 | /* | |
341 | * Check for /dev/loop/<N> subdirectory | |
342 | */ | |
82b4082e | 343 | if (!(lc->flags & LOOPDEV_FL_DEVSUBDIR) && |
10ee5932 KZ |
344 | stat(_PATH_DEV_LOOP, &st) == 0 && S_ISDIR(st.st_mode)) |
345 | lc->flags |= LOOPDEV_FL_DEVSUBDIR; | |
346 | ||
347 | lc->extra_check = 1; | |
348 | } | |
349 | return 0; | |
350 | } | |
351 | ||
352 | /* | |
353 | * @lc: context | |
354 | * | |
355 | * Returns: <0 on error, 0 on success | |
356 | */ | |
357 | int loopcxt_deinit_iterator(struct loopdev_cxt *lc) | |
358 | { | |
7552258a | 359 | struct loopdev_iter *iter; |
10ee5932 KZ |
360 | |
361 | if (!lc) | |
362 | return -EINVAL; | |
363 | ||
aee31ddc KZ |
364 | DBG(lc, loopdev_debug("iter: de-initialize")); |
365 | ||
10ee5932 KZ |
366 | iter = &lc->iter; |
367 | ||
368 | free(iter->minors); | |
369 | if (iter->proc) | |
370 | fclose(iter->proc); | |
e4062c72 KZ |
371 | if (iter->sysblock) |
372 | closedir(iter->sysblock); | |
10ee5932 KZ |
373 | iter->minors = NULL; |
374 | iter->proc = NULL; | |
e4062c72 | 375 | iter->sysblock = NULL; |
10ee5932 KZ |
376 | iter->done = 1; |
377 | return 0; | |
378 | } | |
379 | ||
380 | /* | |
381 | * Same as loopcxt_set_device, but also checks if the device is | |
382 | * associeted with any file. | |
383 | * | |
384 | * Returns: <0 on error, 0 on success, 1 device does not match with | |
385 | * LOOPITER_FL_{USED,FREE} flags. | |
386 | */ | |
387 | static int loopiter_set_device(struct loopdev_cxt *lc, const char *device) | |
388 | { | |
389 | int rc = loopcxt_set_device(lc, device); | |
390 | int used; | |
391 | ||
392 | if (rc) | |
393 | return rc; | |
394 | ||
395 | if (!(lc->iter.flags & LOOPITER_FL_USED) && | |
396 | !(lc->iter.flags & LOOPITER_FL_FREE)) | |
397 | return 0; /* caller does not care about device status */ | |
398 | ||
85794fb0 KZ |
399 | if (!is_loopdev(lc->device)) { |
400 | DBG(lc, loopdev_debug("iter: %s does not exist", lc->device)); | |
401 | return -errno; | |
402 | } | |
403 | ||
404 | DBG(lc, loopdev_debug("iter: %s exist", lc->device)); | |
405 | ||
10ee5932 KZ |
406 | used = loopcxt_get_offset(lc, NULL) == 0; |
407 | ||
408 | if ((lc->iter.flags & LOOPITER_FL_USED) && used) | |
409 | return 0; | |
410 | ||
411 | if ((lc->iter.flags & LOOPITER_FL_FREE) && !used) | |
412 | return 0; | |
413 | ||
85794fb0 | 414 | DBG(lc, loopdev_debug("iter: failed to use %s device", lc->device)); |
defa0710 | 415 | ignore_result( loopcxt_set_device(lc, NULL) ); |
10ee5932 KZ |
416 | return 1; |
417 | } | |
418 | ||
419 | static int cmpnum(const void *p1, const void *p2) | |
420 | { | |
33487796 KZ |
421 | return (((* (int *) p1) > (* (int *) p2)) - |
422 | ((* (int *) p1) < (* (int *) p2))); | |
10ee5932 KZ |
423 | } |
424 | ||
425 | /* | |
426 | * The classic scandir() is more expensive and less portable. | |
427 | * We needn't full loop device names -- loop numbers (loop<N>) | |
428 | * are enough. | |
429 | */ | |
430 | static int loop_scandir(const char *dirname, int **ary, int hasprefix) | |
431 | { | |
432 | DIR *dir; | |
433 | struct dirent *d; | |
434 | unsigned int n, count = 0, arylen = 0; | |
435 | ||
436 | if (!dirname || !ary) | |
437 | return 0; | |
438 | dir = opendir(dirname); | |
439 | if (!dir) | |
440 | return 0; | |
10ee5932 KZ |
441 | free(*ary); |
442 | *ary = NULL; | |
443 | ||
444 | while((d = readdir(dir))) { | |
445 | #ifdef _DIRENT_HAVE_D_TYPE | |
446 | if (d->d_type != DT_BLK && d->d_type != DT_UNKNOWN && | |
447 | d->d_type != DT_LNK) | |
448 | continue; | |
449 | #endif | |
450 | if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, "..")) | |
451 | continue; | |
452 | ||
453 | if (hasprefix) { | |
454 | /* /dev/loop<N> */ | |
455 | if (sscanf(d->d_name, "loop%u", &n) != 1) | |
456 | continue; | |
457 | } else { | |
458 | /* /dev/loop/<N> */ | |
459 | char *end = NULL; | |
460 | ||
461 | n = strtol(d->d_name, &end, 10); | |
462 | if (d->d_name == end || (end && *end) || errno) | |
463 | continue; | |
464 | } | |
465 | if (n < LOOPDEV_DEFAULT_NNODES) | |
466 | continue; /* ignore loop<0..7> */ | |
467 | ||
468 | if (count + 1 > arylen) { | |
469 | int *tmp; | |
470 | ||
471 | arylen += 1; | |
472 | ||
473 | tmp = realloc(*ary, arylen * sizeof(int)); | |
474 | if (!tmp) { | |
475 | free(*ary); | |
2e566efd | 476 | closedir(dir); |
10ee5932 KZ |
477 | return -1; |
478 | } | |
479 | *ary = tmp; | |
480 | } | |
fc8b1f36 KZ |
481 | if (*ary) |
482 | (*ary)[count++] = n; | |
10ee5932 | 483 | } |
fc8b1f36 | 484 | if (count && *ary) |
10ee5932 KZ |
485 | qsort(*ary, count, sizeof(int), cmpnum); |
486 | ||
487 | closedir(dir); | |
488 | return count; | |
489 | } | |
490 | ||
e4062c72 KZ |
491 | /* |
492 | * Set the next *used* loop device according to /proc/partitions. | |
493 | * | |
494 | * Loop devices smaller than 512 bytes are invisible for this function. | |
495 | */ | |
496 | static int loopcxt_next_from_proc(struct loopdev_cxt *lc) | |
497 | { | |
498 | struct loopdev_iter *iter = &lc->iter; | |
499 | char buf[BUFSIZ]; | |
500 | ||
501 | DBG(lc, loopdev_debug("iter: scan /proc/partitions")); | |
502 | ||
503 | if (!iter->proc) | |
b1fa3e22 | 504 | iter->proc = fopen(_PATH_PROC_PARTITIONS, "r" UL_CLOEXECSTR); |
e4062c72 KZ |
505 | if (!iter->proc) |
506 | return 1; | |
507 | ||
508 | while (fgets(buf, sizeof(buf), iter->proc)) { | |
509 | unsigned int m; | |
657d9adb | 510 | char name[128 + 1]; |
e4062c72 KZ |
511 | |
512 | ||
513 | if (sscanf(buf, " %u %*s %*s %128[^\n ]", | |
514 | &m, name) != 2 || m != LOOPDEV_MAJOR) | |
515 | continue; | |
516 | ||
517 | DBG(lc, loopdev_debug("iter: check %s", name)); | |
518 | ||
519 | if (loopiter_set_device(lc, name) == 0) | |
520 | return 0; | |
521 | } | |
522 | ||
523 | return 1; | |
524 | } | |
525 | ||
526 | /* | |
527 | * Set the next *used* loop device according to | |
528 | * /sys/block/loopN/loop/backing_file (kernel >= 2.6.37 is required). | |
529 | * | |
530 | * This is preferred method. | |
531 | */ | |
532 | static int loopcxt_next_from_sysfs(struct loopdev_cxt *lc) | |
533 | { | |
534 | struct loopdev_iter *iter = &lc->iter; | |
535 | struct dirent *d; | |
536 | int fd; | |
537 | ||
538 | DBG(lc, loopdev_debug("iter: scan /sys/block")); | |
539 | ||
540 | if (!iter->sysblock) | |
541 | iter->sysblock = opendir(_PATH_SYS_BLOCK); | |
542 | ||
543 | if (!iter->sysblock) | |
544 | return 1; | |
545 | ||
546 | fd = dirfd(iter->sysblock); | |
547 | ||
548 | while ((d = readdir(iter->sysblock))) { | |
549 | char name[256]; | |
550 | struct stat st; | |
551 | ||
552 | DBG(lc, loopdev_debug("iter: check %s", d->d_name)); | |
553 | ||
554 | if (strcmp(d->d_name, ".") == 0 | |
555 | || strcmp(d->d_name, "..") == 0 | |
556 | || strncmp(d->d_name, "loop", 4) != 0) | |
557 | continue; | |
558 | ||
559 | snprintf(name, sizeof(name), "%s/loop/backing_file", d->d_name); | |
560 | if (fstat_at(fd, _PATH_SYS_BLOCK, name, &st, 0) != 0) | |
561 | continue; | |
562 | ||
563 | if (loopiter_set_device(lc, d->d_name) == 0) | |
564 | return 0; | |
565 | } | |
566 | ||
567 | return 1; | |
568 | } | |
569 | ||
10ee5932 KZ |
570 | /* |
571 | * @lc: context, has to initialized by loopcxt_init_iterator() | |
572 | * | |
573 | * Returns: 0 on success, -1 on error, 1 at the end of scanning. The details | |
574 | * about the current loop device are available by | |
575 | * loopcxt_get_{fd,backing_file,device,offset, ...} functions. | |
576 | */ | |
577 | int loopcxt_next(struct loopdev_cxt *lc) | |
578 | { | |
579 | struct loopdev_iter *iter; | |
580 | ||
581 | if (!lc) | |
582 | return -EINVAL; | |
aee31ddc KZ |
583 | |
584 | DBG(lc, loopdev_debug("iter: next")); | |
585 | ||
10ee5932 KZ |
586 | iter = &lc->iter; |
587 | if (iter->done) | |
588 | return 1; | |
589 | ||
590 | /* A) Look for used loop devices in /proc/partitions ("losetup -a" only) | |
591 | */ | |
592 | if (iter->flags & LOOPITER_FL_USED) { | |
e4062c72 KZ |
593 | int rc; |
594 | ||
595 | if (loopcxt_sysfs_available(lc)) | |
596 | rc = loopcxt_next_from_sysfs(lc); | |
597 | else | |
598 | rc = loopcxt_next_from_proc(lc); | |
599 | if (rc == 0) | |
600 | return 0; | |
10ee5932 KZ |
601 | goto done; |
602 | } | |
603 | ||
604 | /* B) Classic way, try first eight loop devices (default number | |
605 | * of loop devices). This is enough for 99% of all cases. | |
606 | */ | |
607 | if (iter->default_check) { | |
f4bf9592 | 608 | DBG(lc, loopdev_debug("iter: next: default check")); |
10ee5932 KZ |
609 | for (++iter->ncur; iter->ncur < LOOPDEV_DEFAULT_NNODES; |
610 | iter->ncur++) { | |
611 | char name[16]; | |
612 | snprintf(name, sizeof(name), "loop%d", iter->ncur); | |
613 | ||
614 | if (loopiter_set_device(lc, name) == 0) | |
615 | return 0; | |
616 | } | |
617 | iter->default_check = 0; | |
618 | } | |
619 | ||
620 | /* C) the worst possibility, scan whole /dev or /dev/loop/<N> | |
621 | */ | |
622 | if (!iter->minors) { | |
f4bf9592 | 623 | DBG(lc, loopdev_debug("iter: next: scan /dev")); |
10ee5932 KZ |
624 | iter->nminors = (lc->flags & LOOPDEV_FL_DEVSUBDIR) ? |
625 | loop_scandir(_PATH_DEV_LOOP, &iter->minors, 0) : | |
626 | loop_scandir(_PATH_DEV, &iter->minors, 1); | |
627 | iter->ncur = -1; | |
628 | } | |
629 | for (++iter->ncur; iter->ncur < iter->nminors; iter->ncur++) { | |
630 | char name[16]; | |
631 | snprintf(name, sizeof(name), "loop%d", iter->minors[iter->ncur]); | |
632 | ||
633 | if (loopiter_set_device(lc, name) == 0) | |
634 | return 0; | |
635 | } | |
636 | done: | |
637 | loopcxt_deinit_iterator(lc); | |
638 | return 1; | |
639 | } | |
640 | ||
641 | /* | |
642 | * @device: path to device | |
643 | */ | |
644 | int is_loopdev(const char *device) | |
645 | { | |
646 | struct stat st; | |
647 | ||
648 | if (!device) | |
649 | return 0; | |
650 | ||
651 | return (stat(device, &st) == 0 && | |
652 | S_ISBLK(st.st_mode) && | |
653 | major(st.st_rdev) == LOOPDEV_MAJOR); | |
654 | } | |
655 | ||
656 | /* | |
657 | * @lc: context | |
658 | * | |
659 | * Returns result from LOOP_GET_STAT64 ioctl or NULL on error. | |
660 | */ | |
661 | struct loop_info64 *loopcxt_get_info(struct loopdev_cxt *lc) | |
662 | { | |
663 | int fd; | |
664 | ||
85794fb0 KZ |
665 | if (!lc || lc->info_failed) { |
666 | errno = EINVAL; | |
10ee5932 | 667 | return NULL; |
85794fb0 KZ |
668 | } |
669 | errno = 0; | |
10ee5932 KZ |
670 | if (lc->has_info) |
671 | return &lc->info; | |
672 | ||
673 | fd = loopcxt_get_fd(lc); | |
674 | if (fd < 0) | |
675 | return NULL; | |
676 | ||
677 | if (ioctl(fd, LOOP_GET_STATUS64, &lc->info) == 0) { | |
678 | lc->has_info = 1; | |
6c224de1 KZ |
679 | lc->info_failed = 0; |
680 | DBG(lc, loopdev_debug("reading loop_info64 OK")); | |
10ee5932 KZ |
681 | return &lc->info; |
682 | } | |
683 | ||
85794fb0 KZ |
684 | lc->info_failed = 1; |
685 | DBG(lc, loopdev_debug("reading loop_info64 FAILED")); | |
686 | ||
10ee5932 KZ |
687 | return NULL; |
688 | } | |
689 | ||
690 | /* | |
691 | * @lc: context | |
692 | * | |
693 | * Returns (allocated) string with path to the file assicieted | |
694 | * with the current loop device. | |
695 | */ | |
696 | char *loopcxt_get_backing_file(struct loopdev_cxt *lc) | |
697 | { | |
698 | struct sysfs_cxt *sysfs = loopcxt_get_sysfs(lc); | |
699 | char *res = NULL; | |
700 | ||
701 | if (sysfs) | |
fd7f0718 KZ |
702 | /* |
703 | * This is always preffered, the loop_info64 | |
704 | * has too small buffer for the filename. | |
705 | */ | |
10ee5932 KZ |
706 | res = sysfs_strdup(sysfs, "loop/backing_file"); |
707 | ||
708 | if (!res && loopcxt_ioctl_enabled(lc)) { | |
709 | struct loop_info64 *lo = loopcxt_get_info(lc); | |
710 | ||
711 | if (lo) { | |
712 | lo->lo_file_name[LO_NAME_SIZE - 2] = '*'; | |
713 | lo->lo_file_name[LO_NAME_SIZE - 1] = '\0'; | |
714 | res = strdup((char *) lo->lo_file_name); | |
715 | } | |
716 | } | |
aee31ddc | 717 | |
6c224de1 | 718 | DBG(lc, loopdev_debug("get_backing_file [%s]", res)); |
10ee5932 KZ |
719 | return res; |
720 | } | |
721 | ||
722 | /* | |
723 | * @lc: context | |
724 | * @offset: returns offset number for the given device | |
725 | * | |
726 | * Returns: <0 on error, 0 on success | |
727 | */ | |
728 | int loopcxt_get_offset(struct loopdev_cxt *lc, uint64_t *offset) | |
729 | { | |
730 | struct sysfs_cxt *sysfs = loopcxt_get_sysfs(lc); | |
731 | int rc = -EINVAL; | |
732 | ||
733 | if (sysfs) | |
734 | rc = sysfs_read_u64(sysfs, "loop/offset", offset); | |
735 | ||
736 | if (rc && loopcxt_ioctl_enabled(lc)) { | |
737 | struct loop_info64 *lo = loopcxt_get_info(lc); | |
738 | if (lo) { | |
739 | if (offset) | |
740 | *offset = lo->lo_offset; | |
6c224de1 | 741 | rc = 0; |
85794fb0 KZ |
742 | } else |
743 | rc = -errno; | |
10ee5932 KZ |
744 | } |
745 | ||
6c224de1 | 746 | DBG(lc, loopdev_debug("get_offset [rc=%d]", rc)); |
10ee5932 KZ |
747 | return rc; |
748 | } | |
749 | ||
750 | /* | |
751 | * @lc: context | |
752 | * @sizelimit: returns size limit for the given device | |
753 | * | |
754 | * Returns: <0 on error, 0 on success | |
755 | */ | |
756 | int loopcxt_get_sizelimit(struct loopdev_cxt *lc, uint64_t *size) | |
757 | { | |
758 | struct sysfs_cxt *sysfs = loopcxt_get_sysfs(lc); | |
759 | int rc = -EINVAL; | |
760 | ||
761 | if (sysfs) | |
762 | rc = sysfs_read_u64(sysfs, "loop/sizelimit", size); | |
763 | ||
764 | if (rc && loopcxt_ioctl_enabled(lc)) { | |
765 | struct loop_info64 *lo = loopcxt_get_info(lc); | |
766 | if (lo) { | |
767 | if (size) | |
768 | *size = lo->lo_sizelimit; | |
6c224de1 | 769 | rc = 0; |
85794fb0 KZ |
770 | } else |
771 | rc = -errno; | |
10ee5932 KZ |
772 | } |
773 | ||
6c224de1 KZ |
774 | DBG(lc, loopdev_debug("get_sizelimit [rc=%d]", rc)); |
775 | return rc; | |
776 | } | |
777 | ||
778 | /* | |
779 | * @lc: context | |
780 | * @devno: returns encryption type | |
781 | * | |
782 | * Cryptoloop is DEPRECATED! | |
783 | * | |
784 | * Returns: <0 on error, 0 on success | |
785 | */ | |
786 | int loopcxt_get_encrypt_type(struct loopdev_cxt *lc, uint32_t *type) | |
787 | { | |
788 | struct loop_info64 *lo = loopcxt_get_info(lc); | |
85794fb0 | 789 | int rc; |
6c224de1 | 790 | |
85794fb0 | 791 | /* not provided by sysfs */ |
6c224de1 KZ |
792 | if (lo) { |
793 | if (type) | |
794 | *type = lo->lo_encrypt_type; | |
795 | rc = 0; | |
85794fb0 KZ |
796 | } else |
797 | rc = -errno; | |
798 | ||
6c224de1 KZ |
799 | DBG(lc, loopdev_debug("get_encrypt_type [rc=%d]", rc)); |
800 | return rc; | |
801 | } | |
802 | ||
803 | /* | |
804 | * @lc: context | |
805 | * @devno: returns crypt name | |
806 | * | |
807 | * Cryptoloop is DEPRECATED! | |
808 | * | |
809 | * Returns: <0 on error, 0 on success | |
810 | */ | |
811 | const char *loopcxt_get_crypt_name(struct loopdev_cxt *lc) | |
812 | { | |
813 | struct loop_info64 *lo = loopcxt_get_info(lc); | |
814 | ||
815 | if (lo) | |
816 | return (char *) lo->lo_crypt_name; | |
817 | ||
818 | DBG(lc, loopdev_debug("get_crypt_name failed")); | |
819 | return NULL; | |
820 | } | |
821 | ||
822 | /* | |
823 | * @lc: context | |
824 | * @devno: returns backing file devno | |
825 | * | |
826 | * Returns: <0 on error, 0 on success | |
827 | */ | |
828 | int loopcxt_get_backing_devno(struct loopdev_cxt *lc, dev_t *devno) | |
829 | { | |
830 | struct loop_info64 *lo = loopcxt_get_info(lc); | |
85794fb0 | 831 | int rc; |
6c224de1 KZ |
832 | |
833 | if (lo) { | |
834 | if (devno) | |
835 | *devno = lo->lo_device; | |
836 | rc = 0; | |
85794fb0 KZ |
837 | } else |
838 | rc = -errno; | |
839 | ||
6c224de1 KZ |
840 | DBG(lc, loopdev_debug("get_backing_devno [rc=%d]", rc)); |
841 | return rc; | |
842 | } | |
843 | ||
844 | /* | |
845 | * @lc: context | |
846 | * @ino: returns backing file inode | |
847 | * | |
848 | * Returns: <0 on error, 0 on success | |
849 | */ | |
850 | int loopcxt_get_backing_inode(struct loopdev_cxt *lc, ino_t *ino) | |
851 | { | |
852 | struct loop_info64 *lo = loopcxt_get_info(lc); | |
85794fb0 | 853 | int rc; |
6c224de1 KZ |
854 | |
855 | if (lo) { | |
856 | if (ino) | |
857 | *ino = lo->lo_inode; | |
858 | rc = 0; | |
85794fb0 KZ |
859 | } else |
860 | rc = -errno; | |
861 | ||
6c224de1 | 862 | DBG(lc, loopdev_debug("get_backing_inode [rc=%d]", rc)); |
10ee5932 KZ |
863 | return rc; |
864 | } | |
865 | ||
59d749c3 KZ |
866 | /* |
867 | * Check if the kernel supports partitioned loop devices. | |
868 | * | |
869 | * Notes: | |
870 | * - kernels < 3.2 support partitioned loop devices and PT scanning | |
871 | * only if max_part= module paremeter is non-zero | |
872 | * | |
873 | * - kernels >= 3.2 always support partitioned loop devices | |
874 | * | |
875 | * - kernels >= 3.2 always support BLKPG_{ADD,DEL}_PARTITION ioctls | |
876 | * | |
877 | * - kernels >= 3.2 enable PT scanner only if max_part= is non-zero or if the | |
878 | * LO_FLAGS_PARTSCAN flag is set for the device. The PT scanner is disabled | |
879 | * by default. | |
880 | * | |
881 | * See kernel commit e03c8dd14915fabc101aa495828d58598dc5af98. | |
882 | */ | |
883 | int loopmod_supports_partscan(void) | |
884 | { | |
885 | int rc, ret = 0; | |
886 | FILE *f; | |
887 | ||
888 | if (get_linux_version() >= KERNEL_VERSION(3,2,0)) | |
889 | return 1; | |
890 | ||
b1fa3e22 | 891 | f = fopen("/sys/module/loop/parameters/max_part", "r" UL_CLOEXECSTR); |
59d749c3 KZ |
892 | if (!f) |
893 | return 0; | |
894 | rc = fscanf(f, "%d", &ret); | |
895 | fclose(f); | |
8b04761d | 896 | return rc == 1 ? ret : 0; |
59d749c3 KZ |
897 | } |
898 | ||
10ee5932 KZ |
899 | /* |
900 | * @lc: context | |
901 | * | |
59d749c3 KZ |
902 | * Returns: 1 if the partscan flags is set *or* (for old kernels) partitions |
903 | * scannig is enabled for all loop devices. | |
904 | */ | |
905 | int loopcxt_is_partscan(struct loopdev_cxt *lc) | |
906 | { | |
907 | struct sysfs_cxt *sysfs = loopcxt_get_sysfs(lc); | |
908 | ||
909 | if (sysfs) { | |
910 | /* kernel >= 3.2 */ | |
911 | int fl; | |
912 | if (sysfs_read_int(sysfs, "loop/partscan", &fl) == 0) | |
913 | return fl; | |
914 | } | |
915 | ||
916 | /* old kernels (including kernels without loopN/loop/<flags> directory */ | |
917 | return loopmod_supports_partscan(); | |
918 | } | |
919 | ||
920 | /* | |
921 | * @lc: context | |
922 | * | |
923 | * Returns: 1 if the autoclear flags is set. | |
10ee5932 KZ |
924 | */ |
925 | int loopcxt_is_autoclear(struct loopdev_cxt *lc) | |
926 | { | |
927 | struct sysfs_cxt *sysfs = loopcxt_get_sysfs(lc); | |
928 | ||
929 | if (sysfs) { | |
930 | int fl; | |
931 | if (sysfs_read_int(sysfs, "loop/autoclear", &fl) == 0) | |
932 | return fl; | |
933 | } | |
934 | ||
935 | if (loopcxt_ioctl_enabled(lc)) { | |
936 | struct loop_info64 *lo = loopcxt_get_info(lc); | |
937 | if (lo) | |
938 | return lo->lo_flags & LO_FLAGS_AUTOCLEAR; | |
939 | } | |
940 | return 0; | |
941 | } | |
942 | ||
fd7f0718 KZ |
943 | /* |
944 | * @lc: context | |
945 | * | |
59d749c3 | 946 | * Returns: 1 if the readonly flags is set. |
fd7f0718 KZ |
947 | */ |
948 | int loopcxt_is_readonly(struct loopdev_cxt *lc) | |
949 | { | |
950 | struct sysfs_cxt *sysfs = loopcxt_get_sysfs(lc); | |
951 | ||
952 | if (sysfs) { | |
953 | int fl; | |
954 | if (sysfs_read_int(sysfs, "ro", &fl) == 0) | |
955 | return fl; | |
956 | } | |
957 | ||
958 | if (loopcxt_ioctl_enabled(lc)) { | |
959 | struct loop_info64 *lo = loopcxt_get_info(lc); | |
960 | if (lo) | |
961 | return lo->lo_flags & LO_FLAGS_READ_ONLY; | |
962 | } | |
963 | return 0; | |
964 | } | |
965 | ||
6c224de1 KZ |
966 | /* |
967 | * @lc: context | |
968 | * @st: backing file stat or NULL | |
969 | * @backing_file: filename | |
970 | * @offset: offset | |
971 | * @flags: LOOPDEV_FL_OFFSET if @offset should not be ignored | |
972 | * | |
973 | * Returns 1 if the current @lc loopdev is associated with the given backing | |
974 | * file. Note that the preferred way is to use devno and inode number rather | |
975 | * than filename. The @backing_file filename is poor solution usable in case | |
976 | * that you don't have rights to call stat(). | |
977 | * | |
978 | * Don't forget that old kernels provide very restricted (in size) backing | |
979 | * filename by LOOP_GET_STAT64 ioctl only. | |
980 | */ | |
981 | int loopcxt_is_used(struct loopdev_cxt *lc, | |
982 | struct stat *st, | |
983 | const char *backing_file, | |
984 | uint64_t offset, | |
985 | int flags) | |
986 | { | |
987 | ino_t ino; | |
988 | dev_t dev; | |
989 | ||
990 | if (!lc) | |
991 | return 0; | |
992 | ||
993 | DBG(lc, loopdev_debug("checking %s vs. %s", | |
994 | loopcxt_get_device(lc), | |
995 | backing_file)); | |
996 | ||
997 | if (st && loopcxt_get_backing_inode(lc, &ino) == 0 && | |
998 | loopcxt_get_backing_devno(lc, &dev) == 0) { | |
999 | ||
1000 | if (ino == st->st_ino && dev == st->st_dev) | |
1001 | goto found; | |
1002 | ||
1003 | /* don't use filename if we have devno and inode */ | |
1004 | return 0; | |
1005 | } | |
1006 | ||
1007 | /* poor man's solution */ | |
1008 | if (backing_file) { | |
1009 | char *name = loopcxt_get_backing_file(lc); | |
1010 | int rc = name && strcmp(name, backing_file) == 0; | |
1011 | ||
1012 | free(name); | |
1013 | if (rc) | |
1014 | goto found; | |
1015 | } | |
1016 | ||
1017 | return 0; | |
1018 | found: | |
1019 | if (flags & LOOPDEV_FL_OFFSET) { | |
1020 | uint64_t off; | |
1021 | ||
1022 | return loopcxt_get_offset(lc, &off) == 0 && off == offset; | |
1023 | } | |
1024 | return 1; | |
1025 | } | |
1026 | ||
fd7f0718 KZ |
1027 | /* |
1028 | * The setting is removed by loopcxt_set_device() loopcxt_next()! | |
1029 | */ | |
10ee5932 KZ |
1030 | int loopcxt_set_offset(struct loopdev_cxt *lc, uint64_t offset) |
1031 | { | |
1032 | if (!lc) | |
1033 | return -EINVAL; | |
1034 | lc->info.lo_offset = offset; | |
aee31ddc KZ |
1035 | |
1036 | DBG(lc, loopdev_debug("set offset=%jd", offset)); | |
10ee5932 KZ |
1037 | return 0; |
1038 | } | |
1039 | ||
fd7f0718 KZ |
1040 | /* |
1041 | * The setting is removed by loopcxt_set_device() loopcxt_next()! | |
1042 | */ | |
10ee5932 KZ |
1043 | int loopcxt_set_sizelimit(struct loopdev_cxt *lc, uint64_t sizelimit) |
1044 | { | |
1045 | if (!lc) | |
1046 | return -EINVAL; | |
1047 | lc->info.lo_sizelimit = sizelimit; | |
aee31ddc KZ |
1048 | |
1049 | DBG(lc, loopdev_debug("set sizelimit=%jd", sizelimit)); | |
10ee5932 KZ |
1050 | return 0; |
1051 | } | |
1052 | ||
1053 | /* | |
1054 | * @lc: context | |
1055 | * @flags: kernel LO_FLAGS_{READ_ONLY,USE_AOPS,AUTOCLEAR} flags | |
1056 | * | |
fd7f0718 KZ |
1057 | * The setting is removed by loopcxt_set_device() loopcxt_next()! |
1058 | * | |
10ee5932 KZ |
1059 | * Returns: 0 on success, <0 on error. |
1060 | */ | |
1061 | int loopcxt_set_flags(struct loopdev_cxt *lc, uint32_t flags) | |
1062 | { | |
1063 | if (!lc) | |
1064 | return -EINVAL; | |
1065 | lc->info.lo_flags = flags; | |
aee31ddc KZ |
1066 | |
1067 | DBG(lc, loopdev_debug("set flags=%u", (unsigned) flags)); | |
10ee5932 KZ |
1068 | return 0; |
1069 | } | |
1070 | ||
1071 | /* | |
1072 | * @lc: context | |
1073 | * @filename: backing file path (the path will be canonicalized) | |
1074 | * | |
fd7f0718 KZ |
1075 | * The setting is removed by loopcxt_set_device() loopcxt_next()! |
1076 | * | |
10ee5932 KZ |
1077 | * Returns: 0 on success, <0 on error. |
1078 | */ | |
1079 | int loopcxt_set_backing_file(struct loopdev_cxt *lc, const char *filename) | |
1080 | { | |
1081 | if (!lc) | |
1082 | return -EINVAL; | |
1083 | ||
1084 | lc->filename = canonicalize_path(filename); | |
1085 | if (!lc->filename) | |
1086 | return -errno; | |
1087 | ||
1088 | strncpy((char *)lc->info.lo_file_name, lc->filename, LO_NAME_SIZE); | |
1089 | lc->info.lo_file_name[LO_NAME_SIZE- 1] = '\0'; | |
1090 | ||
aee31ddc | 1091 | DBG(lc, loopdev_debug("set backing file=%s", lc->info.lo_file_name)); |
10ee5932 KZ |
1092 | return 0; |
1093 | } | |
1094 | ||
293714c0 JM |
1095 | /* |
1096 | * In kernels prior to v3.9, if the offset or sizelimit options | |
1097 | * are used, the block device's size won't be synced automatically. | |
1098 | * blockdev --getsize64 and filesystems will use the backing | |
1099 | * file size until the block device has been re-opened or the | |
1100 | * LOOP_SET_CAPACITY ioctl is called to sync the sizes. | |
1101 | * | |
1102 | * Since mount -oloop uses the LO_FLAGS_AUTOCLEAR option and passes | |
1103 | * the open file descriptor to the mount system call, we need to use | |
1104 | * the ioctl. Calling losetup directly doesn't have this problem since | |
1105 | * it closes the device when it exits and whatever consumes the device | |
1106 | * next will re-open it, causing the resync. | |
1107 | */ | |
1108 | static int loopcxt_check_size(struct loopdev_cxt *lc, int file_fd) | |
1109 | { | |
1110 | uint64_t size, expected_size; | |
1111 | int dev_fd; | |
1112 | struct stat st; | |
1113 | ||
1114 | if (!lc->info.lo_offset && !lc->info.lo_sizelimit) | |
1115 | return 0; | |
1116 | ||
01307ecf KZ |
1117 | if (fstat(file_fd, &st)) { |
1118 | DBG(lc, loopdev_debug("failed to fstat backing file")); | |
293714c0 | 1119 | return -errno; |
01307ecf | 1120 | } |
e3b6cb87 KZ |
1121 | if (S_ISBLK(st.st_mode)) { |
1122 | if (blkdev_get_size(file_fd, | |
01307ecf KZ |
1123 | (unsigned long long *) &expected_size)) { |
1124 | DBG(lc, loopdev_debug("failed to determine device size")); | |
e3b6cb87 | 1125 | return -errno; |
01307ecf | 1126 | } |
e3b6cb87 KZ |
1127 | } else |
1128 | expected_size = st.st_size; | |
1129 | ||
1130 | if (expected_size == 0 || expected_size <= lc->info.lo_offset) { | |
1131 | DBG(lc, loopdev_debug("failed to determine expected size")); | |
1132 | return 0; /* ignore this error */ | |
1133 | } | |
293714c0 JM |
1134 | |
1135 | if (lc->info.lo_offset > 0) | |
1136 | expected_size -= lc->info.lo_offset; | |
1137 | ||
1138 | if (lc->info.lo_sizelimit > 0 && lc->info.lo_sizelimit < expected_size) | |
1139 | expected_size = lc->info.lo_sizelimit; | |
1140 | ||
1141 | dev_fd = loopcxt_get_fd(lc); | |
01307ecf KZ |
1142 | if (dev_fd < 0) { |
1143 | DBG(lc, loopdev_debug("failed to get loop FD")); | |
293714c0 | 1144 | return -errno; |
01307ecf | 1145 | } |
293714c0 | 1146 | |
01307ecf KZ |
1147 | if (blkdev_get_size(dev_fd, (unsigned long long *) &size)) { |
1148 | DBG(lc, loopdev_debug("failed to determine loopdev size")); | |
293714c0 | 1149 | return -errno; |
01307ecf | 1150 | } |
293714c0 | 1151 | |
a7d5202b KZ |
1152 | /* It's block device, so, align to 512-byte sectors */ |
1153 | if (expected_size % 512) { | |
1154 | DBG(lc, loopdev_debug("expected size misaligned to 512-byte sectors")); | |
1155 | expected_size = (expected_size >> 9) << 9; | |
1156 | } | |
1157 | ||
293714c0 | 1158 | if (expected_size != size) { |
e3b6cb87 KZ |
1159 | DBG(lc, loopdev_debug("warning: loopdev and expected " |
1160 | "size dismatch (%ju/%ju)", | |
1161 | size, expected_size)); | |
1162 | ||
293714c0 JM |
1163 | if (loopcxt_set_capacity(lc)) { |
1164 | /* ioctl not available */ | |
1165 | if (errno == ENOTTY || errno == EINVAL) | |
1166 | errno = ERANGE; | |
1167 | return -errno; | |
1168 | } | |
1169 | ||
1170 | if (blkdev_get_size(dev_fd, (unsigned long long *) &size)) | |
1171 | return -errno; | |
1172 | ||
01307ecf KZ |
1173 | if (expected_size != size) { |
1174 | errno = ERANGE; | |
1175 | DBG(lc, loopdev_debug("failed to set loopdev size, " | |
1176 | "size: %ju, expected: %ju", | |
1177 | size, expected_size)); | |
1178 | return -errno; | |
1179 | } | |
293714c0 JM |
1180 | } |
1181 | ||
1182 | return 0; | |
1183 | } | |
1184 | ||
10ee5932 KZ |
1185 | /* |
1186 | * @cl: context | |
1187 | * | |
1188 | * Associate the current device (see loopcxt_{set,get}_device()) with | |
1189 | * a file (see loopcxt_set_backing_file()). | |
1190 | * | |
fd7f0718 KZ |
1191 | * The device is initialized read-write by default. If you want read-only |
1192 | * device then set LO_FLAGS_READ_ONLY by loopcxt_set_flags(). The LOOPDEV_FL_* | |
1193 | * flags are ignored and modified according to LO_FLAGS_*. | |
1194 | * | |
1195 | * If the device is already open by loopcxt_get_fd() then this setup device | |
1196 | * function will re-open the device to fix read/write mode. | |
1197 | * | |
1198 | * The device is also initialized read-only if the backing file is not | |
1199 | * possible to open read-write (e.g. read-only FS). | |
10ee5932 KZ |
1200 | * |
1201 | * Returns: <0 on error, 0 on success. | |
1202 | */ | |
1203 | int loopcxt_setup_device(struct loopdev_cxt *lc) | |
1204 | { | |
663bf040 | 1205 | int file_fd, dev_fd, mode = O_RDWR, rc = -1, cnt = 0; |
10ee5932 KZ |
1206 | |
1207 | if (!lc || !*lc->device || !lc->filename) | |
1208 | return -EINVAL; | |
1209 | ||
aee31ddc KZ |
1210 | DBG(lc, loopdev_debug("device setup requested")); |
1211 | ||
10ee5932 KZ |
1212 | /* |
1213 | * Open backing file and device | |
1214 | */ | |
fd7f0718 KZ |
1215 | if (lc->info.lo_flags & LO_FLAGS_READ_ONLY) |
1216 | mode = O_RDONLY; | |
10ee5932 | 1217 | |
b1fa3e22 | 1218 | if ((file_fd = open(lc->filename, mode | O_CLOEXEC)) < 0) { |
10ee5932 KZ |
1219 | if (mode != O_RDONLY && (errno == EROFS || errno == EACCES)) |
1220 | file_fd = open(lc->filename, mode = O_RDONLY); | |
1221 | ||
aee31ddc KZ |
1222 | if (file_fd < 0) { |
1223 | DBG(lc, loopdev_debug("open backing file failed: %m")); | |
10ee5932 | 1224 | return -errno; |
aee31ddc | 1225 | } |
10ee5932 | 1226 | } |
d356c5d2 | 1227 | DBG(lc, loopdev_debug("setup: backing file open: OK")); |
10ee5932 | 1228 | |
fd7f0718 | 1229 | if (lc->fd != -1 && lc->mode != mode) { |
f4bf9592 | 1230 | DBG(lc, loopdev_debug("closing already open device (mode mismatch)")); |
fd7f0718 KZ |
1231 | close(lc->fd); |
1232 | lc->fd = -1; | |
1233 | lc->mode = 0; | |
1234 | } | |
1235 | ||
10ee5932 | 1236 | if (mode == O_RDONLY) { |
fd7f0718 KZ |
1237 | lc->flags |= LOOPDEV_FL_RDONLY; /* open() mode */ |
1238 | lc->info.lo_flags |= LO_FLAGS_READ_ONLY; /* kernel loopdev mode */ | |
1239 | } else { | |
1240 | lc->flags |= LOOPDEV_FL_RDWR; /* open() mode */ | |
1241 | lc->info.lo_flags &= ~LO_FLAGS_READ_ONLY; | |
1242 | lc->flags &= ~LOOPDEV_FL_RDONLY; | |
1243 | } | |
10ee5932 | 1244 | |
663bf040 KZ |
1245 | do { |
1246 | errno = 0; | |
1247 | dev_fd = loopcxt_get_fd(lc); | |
1248 | if (dev_fd >= 0 || lc->control_ok == 0) | |
1249 | break; | |
1250 | if (errno != EACCES && errno != ENOENT) | |
1251 | break; | |
1252 | /* We have permissions to open /dev/loop-control, but open | |
1253 | * /dev/loopN failed with EACCES, it's probably because udevd | |
1254 | * does not applied chown yet. Let's wait a moment. */ | |
1255 | xusleep(25000); | |
1256 | } while (cnt++ < 16); | |
1257 | ||
10ee5932 KZ |
1258 | if (dev_fd < 0) { |
1259 | rc = -errno; | |
1260 | goto err; | |
1261 | } | |
1262 | ||
d356c5d2 KZ |
1263 | DBG(lc, loopdev_debug("setup: device open: OK")); |
1264 | ||
10ee5932 KZ |
1265 | /* |
1266 | * Set FD | |
1267 | */ | |
1268 | if (ioctl(dev_fd, LOOP_SET_FD, file_fd) < 0) { | |
1269 | rc = -errno; | |
aee31ddc | 1270 | DBG(lc, loopdev_debug("LOOP_SET_FD failed: %m")); |
10ee5932 KZ |
1271 | goto err; |
1272 | } | |
d356c5d2 KZ |
1273 | |
1274 | DBG(lc, loopdev_debug("setup: LOOP_SET_FD: OK")); | |
1275 | ||
aee31ddc KZ |
1276 | if (ioctl(dev_fd, LOOP_SET_STATUS64, &lc->info)) { |
1277 | DBG(lc, loopdev_debug("LOOP_SET_STATUS64 failed: %m")); | |
10ee5932 | 1278 | goto err; |
aee31ddc | 1279 | } |
d356c5d2 KZ |
1280 | |
1281 | DBG(lc, loopdev_debug("setup: LOOP_SET_STATUS64: OK")); | |
1282 | ||
293714c0 JM |
1283 | if ((rc = loopcxt_check_size(lc, file_fd))) |
1284 | goto err; | |
1285 | ||
1286 | close(file_fd); | |
293714c0 | 1287 | |
10ee5932 KZ |
1288 | memset(&lc->info, 0, sizeof(lc->info)); |
1289 | lc->has_info = 0; | |
6c224de1 | 1290 | lc->info_failed = 0; |
10ee5932 | 1291 | |
8fbbe528 | 1292 | DBG(lc, loopdev_debug("setup success [rc=0]")); |
10ee5932 KZ |
1293 | return 0; |
1294 | err: | |
1295 | if (file_fd >= 0) | |
1296 | close(file_fd); | |
1297 | if (dev_fd >= 0) | |
1298 | ioctl(dev_fd, LOOP_CLR_FD, 0); | |
1299 | ||
8fbbe528 | 1300 | DBG(lc, loopdev_debug("setup failed [rc=%d]", rc)); |
10ee5932 KZ |
1301 | return rc; |
1302 | } | |
1303 | ||
293714c0 JM |
1304 | int loopcxt_set_capacity(struct loopdev_cxt *lc) |
1305 | { | |
1306 | int fd = loopcxt_get_fd(lc); | |
1307 | ||
1308 | if (fd < 0) | |
1309 | return -EINVAL; | |
1310 | ||
1311 | /* Kernels prior to v2.6.30 don't support this ioctl */ | |
1312 | if (ioctl(fd, LOOP_SET_CAPACITY, 0) < 0) { | |
1313 | int rc = -errno; | |
1314 | DBG(lc, loopdev_debug("LOOP_SET_CAPACITY failed: %m")); | |
1315 | return rc; | |
1316 | } | |
1317 | ||
1318 | DBG(lc, loopdev_debug("capacity set")); | |
1319 | return 0; | |
1320 | } | |
1321 | ||
10ee5932 KZ |
1322 | int loopcxt_delete_device(struct loopdev_cxt *lc) |
1323 | { | |
1324 | int fd = loopcxt_get_fd(lc); | |
1325 | ||
1326 | if (fd < 0) | |
1327 | return -EINVAL; | |
1328 | ||
aee31ddc KZ |
1329 | if (ioctl(fd, LOOP_CLR_FD, 0) < 0) { |
1330 | DBG(lc, loopdev_debug("LOOP_CLR_FD failed: %m")); | |
10ee5932 | 1331 | return -errno; |
aee31ddc KZ |
1332 | } |
1333 | ||
1334 | DBG(lc, loopdev_debug("device removed")); | |
10ee5932 KZ |
1335 | return 0; |
1336 | } | |
1337 | ||
3cb2413b KZ |
1338 | int loopcxt_add_device(struct loopdev_cxt *lc) |
1339 | { | |
1340 | int rc = -EINVAL; | |
1341 | int ctl, nr = -1; | |
1342 | const char *p, *dev = loopcxt_get_device(lc); | |
1343 | ||
1344 | if (!dev) | |
1345 | goto done; | |
1346 | ||
1347 | if (!(lc->flags & LOOPDEV_FL_CONTROL)) { | |
1348 | rc = -ENOSYS; | |
1349 | goto done; | |
1350 | } | |
1351 | ||
1352 | p = strrchr(dev, '/'); | |
1353 | if (!p || (sscanf(p, "/loop%d", &nr) != 1 && sscanf(p, "/%d", &nr) != 1) | |
1354 | || nr < 0) | |
1355 | goto done; | |
1356 | ||
1357 | ctl = open(_PATH_DEV_LOOPCTL, O_RDWR|O_CLOEXEC); | |
1358 | if (ctl >= 0) { | |
1359 | DBG(lc, loopdev_debug("add_device %d", nr)); | |
1360 | rc = ioctl(ctl, LOOP_CTL_ADD, nr); | |
1361 | close(ctl); | |
1362 | } | |
663bf040 | 1363 | lc->control_ok = rc >= 0 ? 1 : 0; |
3cb2413b KZ |
1364 | done: |
1365 | DBG(lc, loopdev_debug("add_device done [rc=%d]", rc)); | |
1366 | return rc; | |
1367 | } | |
1368 | ||
59d749c3 KZ |
1369 | /* |
1370 | * Note that LOOP_CTL_GET_FREE ioctl is supported since kernel 3.1. In older | |
1371 | * kernels we have to check all loop devices to found unused one. | |
1372 | * | |
1373 | * See kernel commit 770fe30a46a12b6fb6b63fbe1737654d28e8484. | |
1374 | */ | |
10ee5932 KZ |
1375 | int loopcxt_find_unused(struct loopdev_cxt *lc) |
1376 | { | |
0b14bf7a | 1377 | int rc = -1; |
10ee5932 | 1378 | |
aee31ddc KZ |
1379 | DBG(lc, loopdev_debug("find_unused requested")); |
1380 | ||
0b14bf7a | 1381 | if (lc->flags & LOOPDEV_FL_CONTROL) { |
b1fa3e22 | 1382 | int ctl = open(_PATH_DEV_LOOPCTL, O_RDWR|O_CLOEXEC); |
10ee5932 | 1383 | |
0b14bf7a KZ |
1384 | if (ctl >= 0) |
1385 | rc = ioctl(ctl, LOOP_CTL_GET_FREE); | |
1386 | if (rc >= 0) { | |
1387 | char name[16]; | |
1388 | snprintf(name, sizeof(name), "loop%d", rc); | |
1389 | ||
1390 | rc = loopiter_set_device(lc, name); | |
1391 | } | |
663bf040 | 1392 | lc->control_ok = ctl >= 0 && rc == 0 ? 1 : 0; |
0b14bf7a KZ |
1393 | if (ctl >= 0) |
1394 | close(ctl); | |
1395 | DBG(lc, loopdev_debug("find_unused by loop-control [rc=%d]", rc)); | |
1396 | } | |
1397 | ||
1398 | if (rc < 0) { | |
1399 | rc = loopcxt_init_iterator(lc, LOOPITER_FL_FREE); | |
1400 | if (rc) | |
1401 | return rc; | |
10ee5932 | 1402 | |
0b14bf7a KZ |
1403 | rc = loopcxt_next(lc); |
1404 | loopcxt_deinit_iterator(lc); | |
1405 | DBG(lc, loopdev_debug("find_unused by scan [rc=%d]", rc)); | |
1406 | } | |
10ee5932 KZ |
1407 | return rc; |
1408 | } | |
1409 | ||
1410 | ||
1411 | ||
1412 | /* | |
1413 | * Return: TRUE/FALSE | |
1414 | */ | |
1415 | int loopdev_is_autoclear(const char *device) | |
1416 | { | |
1417 | struct loopdev_cxt lc; | |
1418 | int rc; | |
1419 | ||
1420 | if (!device) | |
1421 | return 0; | |
1422 | ||
defa0710 KZ |
1423 | rc = loopcxt_init(&lc, 0); |
1424 | if (!rc) | |
1425 | rc = loopcxt_set_device(&lc, device); | |
1426 | if (!rc) | |
1427 | rc = loopcxt_is_autoclear(&lc); | |
10ee5932 | 1428 | |
defa0710 | 1429 | loopcxt_deinit(&lc); |
10ee5932 KZ |
1430 | return rc; |
1431 | } | |
1432 | ||
1433 | char *loopdev_get_backing_file(const char *device) | |
1434 | { | |
1435 | struct loopdev_cxt lc; | |
defa0710 | 1436 | char *res = NULL; |
10ee5932 KZ |
1437 | |
1438 | if (!device) | |
1439 | return NULL; | |
defa0710 KZ |
1440 | if (loopcxt_init(&lc, 0)) |
1441 | return NULL; | |
1442 | if (loopcxt_set_device(&lc, device) == 0) | |
1443 | res = loopcxt_get_backing_file(&lc); | |
10ee5932 | 1444 | |
10ee5932 | 1445 | loopcxt_deinit(&lc); |
10ee5932 KZ |
1446 | return res; |
1447 | } | |
1448 | ||
1449 | /* | |
1450 | * Returns: TRUE/FALSE | |
1451 | */ | |
1452 | int loopdev_is_used(const char *device, const char *filename, | |
1453 | uint64_t offset, int flags) | |
1454 | { | |
1455 | struct loopdev_cxt lc; | |
6c224de1 | 1456 | struct stat st; |
10ee5932 KZ |
1457 | int rc = 0; |
1458 | ||
8b470b20 | 1459 | if (!device || !filename) |
10ee5932 KZ |
1460 | return 0; |
1461 | ||
defa0710 KZ |
1462 | rc = loopcxt_init(&lc, 0); |
1463 | if (!rc) | |
1464 | rc = loopcxt_set_device(&lc, device); | |
1465 | if (rc) | |
1466 | return rc; | |
10ee5932 | 1467 | |
6c224de1 KZ |
1468 | rc = !stat(filename, &st); |
1469 | rc = loopcxt_is_used(&lc, rc ? &st : NULL, filename, offset, flags); | |
10ee5932 | 1470 | |
10ee5932 | 1471 | loopcxt_deinit(&lc); |
10ee5932 KZ |
1472 | return rc; |
1473 | } | |
1474 | ||
1475 | int loopdev_delete(const char *device) | |
1476 | { | |
1477 | struct loopdev_cxt lc; | |
1478 | int rc; | |
1479 | ||
8b470b20 KZ |
1480 | if (!device) |
1481 | return -EINVAL; | |
1482 | ||
defa0710 KZ |
1483 | rc = loopcxt_init(&lc, 0); |
1484 | if (!rc) | |
1485 | rc = loopcxt_set_device(&lc, device); | |
10ee5932 KZ |
1486 | if (!rc) |
1487 | rc = loopcxt_delete_device(&lc); | |
1488 | loopcxt_deinit(&lc); | |
1489 | return rc; | |
1490 | } | |
1491 | ||
1492 | /* | |
1493 | * Returns: 0 = success, < 0 error, 1 not found | |
1494 | */ | |
1495 | int loopcxt_find_by_backing_file(struct loopdev_cxt *lc, const char *filename, | |
1496 | uint64_t offset, int flags) | |
1497 | { | |
6c224de1 KZ |
1498 | int rc, hasst; |
1499 | struct stat st; | |
10ee5932 KZ |
1500 | |
1501 | if (!filename) | |
1502 | return -EINVAL; | |
1503 | ||
6c224de1 KZ |
1504 | hasst = !stat(filename, &st); |
1505 | ||
10ee5932 KZ |
1506 | rc = loopcxt_init_iterator(lc, LOOPITER_FL_USED); |
1507 | if (rc) | |
1508 | return rc; | |
1509 | ||
6c224de1 | 1510 | while ((rc = loopcxt_next(lc)) == 0) { |
10ee5932 | 1511 | |
6c224de1 KZ |
1512 | if (loopcxt_is_used(lc, hasst ? &st : NULL, |
1513 | filename, offset, flags)) | |
1514 | break; | |
10ee5932 KZ |
1515 | } |
1516 | ||
1517 | loopcxt_deinit_iterator(lc); | |
1518 | return rc; | |
1519 | } | |
1520 | ||
1521 | /* | |
1522 | * Returns allocated string with device name | |
1523 | */ | |
1524 | char *loopdev_find_by_backing_file(const char *filename, uint64_t offset, int flags) | |
1525 | { | |
1526 | struct loopdev_cxt lc; | |
1527 | char *res = NULL; | |
1528 | ||
1529 | if (!filename) | |
1530 | return NULL; | |
1531 | ||
defa0710 KZ |
1532 | if (loopcxt_init(&lc, 0)) |
1533 | return NULL; | |
06f588f7 | 1534 | if (loopcxt_find_by_backing_file(&lc, filename, offset, flags) == 0) |
10ee5932 KZ |
1535 | res = loopcxt_strdup_device(&lc); |
1536 | loopcxt_deinit(&lc); | |
1537 | ||
1538 | return res; | |
1539 | } | |
1540 | ||
d5688130 KZ |
1541 | /* |
1542 | * Returns number of loop devices associated with @file, if only one loop | |
1543 | * device is associeted with the given @filename and @loopdev is not NULL then | |
1544 | * @loopdev returns name of the device. | |
1545 | */ | |
1546 | int loopdev_count_by_backing_file(const char *filename, char **loopdev) | |
1547 | { | |
1548 | struct loopdev_cxt lc; | |
defa0710 | 1549 | int count = 0, rc; |
d5688130 KZ |
1550 | |
1551 | if (!filename) | |
1552 | return -1; | |
1553 | ||
defa0710 KZ |
1554 | rc = loopcxt_init(&lc, 0); |
1555 | if (rc) | |
1556 | return rc; | |
d5688130 KZ |
1557 | if (loopcxt_init_iterator(&lc, LOOPITER_FL_USED)) |
1558 | return -1; | |
1559 | ||
1560 | while(loopcxt_next(&lc) == 0) { | |
1561 | char *backing = loopcxt_get_backing_file(&lc); | |
1562 | ||
1563 | if (!backing || strcmp(backing, filename)) { | |
1564 | free(backing); | |
1565 | continue; | |
1566 | } | |
1567 | ||
1568 | free(backing); | |
1569 | if (loopdev && count == 0) | |
1570 | *loopdev = loopcxt_strdup_device(&lc); | |
1571 | count++; | |
1572 | } | |
1573 | ||
1574 | loopcxt_deinit(&lc); | |
1575 | ||
1576 | if (loopdev && count > 1) { | |
1577 | free(*loopdev); | |
1578 | *loopdev = NULL; | |
1579 | } | |
1580 | return count; | |
1581 | } | |
1582 | ||
10ee5932 KZ |
1583 | |
1584 | #ifdef TEST_PROGRAM_LOOPDEV | |
1585 | #include <errno.h> | |
1586 | #include <err.h> | |
10ee5932 | 1587 | |
aee31ddc | 1588 | static void test_loop_info(const char *device, int flags, int debug) |
10ee5932 KZ |
1589 | { |
1590 | struct loopdev_cxt lc; | |
1591 | char *p; | |
1592 | uint64_t u64; | |
1593 | ||
defa0710 | 1594 | if (loopcxt_init(&lc, flags)) |
510a1a34 | 1595 | return; |
aee31ddc KZ |
1596 | loopcxt_enable_debug(&lc, debug); |
1597 | ||
10ee5932 KZ |
1598 | if (loopcxt_set_device(&lc, device)) |
1599 | err(EXIT_FAILURE, "failed to set device"); | |
1600 | ||
1601 | p = loopcxt_get_backing_file(&lc); | |
1602 | printf("\tBACKING FILE: %s\n", p); | |
1603 | free(p); | |
1604 | ||
1605 | if (loopcxt_get_offset(&lc, &u64) == 0) | |
1606 | printf("\tOFFSET: %jd\n", u64); | |
1607 | ||
1608 | if (loopcxt_get_sizelimit(&lc, &u64) == 0) | |
1609 | printf("\tSIZE LIMIT: %jd\n", u64); | |
1610 | ||
1611 | printf("\tAUTOCLEAR: %s\n", loopcxt_is_autoclear(&lc) ? "YES" : "NOT"); | |
1612 | ||
1613 | loopcxt_deinit(&lc); | |
1614 | } | |
1615 | ||
aee31ddc | 1616 | static void test_loop_scan(int flags, int debug) |
10ee5932 KZ |
1617 | { |
1618 | struct loopdev_cxt lc; | |
1619 | int rc; | |
1620 | ||
defa0710 KZ |
1621 | if (loopcxt_init(&lc, 0)) |
1622 | return; | |
aee31ddc | 1623 | loopcxt_enable_debug(&lc, debug); |
10ee5932 KZ |
1624 | |
1625 | if (loopcxt_init_iterator(&lc, flags)) | |
1626 | err(EXIT_FAILURE, "iterator initlization failed"); | |
1627 | ||
1628 | while((rc = loopcxt_next(&lc)) == 0) { | |
1629 | const char *device = loopcxt_get_device(&lc); | |
1630 | ||
1631 | if (flags & LOOPITER_FL_USED) { | |
1632 | char *backing = loopcxt_get_backing_file(&lc); | |
1633 | printf("\t%s: %s\n", device, backing); | |
1634 | free(backing); | |
1635 | } else | |
1636 | printf("\t%s\n", device); | |
1637 | } | |
1638 | ||
1639 | if (rc < 0) | |
1640 | err(EXIT_FAILURE, "loopdevs scanning failed"); | |
1641 | ||
1642 | loopcxt_deinit(&lc); | |
1643 | } | |
1644 | ||
aee31ddc | 1645 | static int test_loop_setup(const char *filename, const char *device, int debug) |
10ee5932 KZ |
1646 | { |
1647 | struct loopdev_cxt lc; | |
defa0710 | 1648 | int rc; |
10ee5932 | 1649 | |
defa0710 KZ |
1650 | rc = loopcxt_init(&lc, 0); |
1651 | if (rc) | |
1652 | return rc; | |
aee31ddc | 1653 | loopcxt_enable_debug(&lc, debug); |
10ee5932 | 1654 | |
10ee5932 KZ |
1655 | if (device) { |
1656 | rc = loopcxt_set_device(&lc, device); | |
1657 | if (rc) | |
1658 | err(EXIT_FAILURE, "failed to set device: %s", device); | |
1659 | } | |
1660 | ||
1661 | do { | |
1662 | if (!device) { | |
1663 | rc = loopcxt_find_unused(&lc); | |
1664 | if (rc) | |
ad2d0d85 | 1665 | err(EXIT_FAILURE, "failed to find unused device"); |
10ee5932 KZ |
1666 | printf("Trying to use '%s'\n", loopcxt_get_device(&lc)); |
1667 | } | |
1668 | ||
fd7f0718 KZ |
1669 | if (loopcxt_set_backing_file(&lc, filename)) |
1670 | err(EXIT_FAILURE, "failed to set backing file"); | |
1671 | ||
10ee5932 KZ |
1672 | rc = loopcxt_setup_device(&lc); |
1673 | if (rc == 0) | |
1674 | break; /* success */ | |
1675 | ||
1676 | if (device || rc != -EBUSY) | |
1677 | err(EXIT_FAILURE, "failed to setup device for %s", | |
1678 | lc.filename); | |
1679 | ||
1680 | printf("device stolen...trying again\n"); | |
1681 | } while (1); | |
1682 | ||
1683 | loopcxt_deinit(&lc); | |
1684 | ||
1685 | return 0; | |
1686 | } | |
1687 | ||
1688 | int main(int argc, char *argv[]) | |
1689 | { | |
aee31ddc KZ |
1690 | int dbg; |
1691 | ||
10ee5932 KZ |
1692 | if (argc < 2) |
1693 | goto usage; | |
1694 | ||
aee31ddc KZ |
1695 | dbg = getenv("LOOPDEV_DEBUG") == NULL ? 0 : 1; |
1696 | ||
10ee5932 KZ |
1697 | if (argc == 3 && strcmp(argv[1], "--info") == 0) { |
1698 | printf("---sysfs & ioctl:---\n"); | |
aee31ddc | 1699 | test_loop_info(argv[2], 0, dbg); |
10ee5932 | 1700 | printf("---sysfs only:---\n"); |
aee31ddc | 1701 | test_loop_info(argv[2], LOOPDEV_FL_NOIOCTL, dbg); |
10ee5932 | 1702 | printf("---ioctl only:---\n"); |
aee31ddc | 1703 | test_loop_info(argv[2], LOOPDEV_FL_NOSYSFS, dbg); |
10ee5932 KZ |
1704 | |
1705 | } else if (argc == 2 && strcmp(argv[1], "--used") == 0) { | |
1706 | printf("---all used devices---\n"); | |
aee31ddc | 1707 | test_loop_scan(LOOPITER_FL_USED, dbg); |
10ee5932 KZ |
1708 | |
1709 | } else if (argc == 2 && strcmp(argv[1], "--free") == 0) { | |
1710 | printf("---all free devices---\n"); | |
aee31ddc | 1711 | test_loop_scan(LOOPITER_FL_FREE, dbg); |
10ee5932 KZ |
1712 | |
1713 | } else if (argc >= 3 && strcmp(argv[1], "--setup") == 0) { | |
aee31ddc | 1714 | test_loop_setup(argv[2], argv[3], dbg); |
10ee5932 KZ |
1715 | |
1716 | } else if (argc == 3 && strcmp(argv[1], "--delete") == 0) { | |
1717 | if (loopdev_delete(argv[2])) | |
1718 | errx(EXIT_FAILURE, "failed to deinitialize device %s", argv[2]); | |
1719 | } else | |
1720 | goto usage; | |
1721 | ||
1722 | return EXIT_SUCCESS; | |
1723 | ||
1724 | usage: | |
1725 | errx(EXIT_FAILURE, "usage: \n" | |
1726 | " %1$s --info <device>\n" | |
1727 | " %1$s --free\n" | |
1728 | " %1$s --used\n" | |
1729 | " %1$s --setup <filename> [<device>]\n" | |
1730 | " %1$s --delete\n", | |
1731 | argv[0]); | |
1732 | } | |
1733 | ||
1734 | #endif /* TEST_PROGRAM */ |