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Commit | Line | Data |
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3c16d0cb CB |
1 | /* |
2 | * lxc: linux Container library | |
3 | * | |
4 | * (C) Copyright IBM Corp. 2007, 2008 | |
5 | * | |
6 | * Authors: | |
7 | * Daniel Lezcano <daniel.lezcano at free.fr> | |
8 | * | |
9 | * This library is free software; you can redistribute it and/or | |
10 | * modify it under the terms of the GNU Lesser General Public | |
11 | * License as published by the Free Software Foundation; either | |
12 | * version 2.1 of the License, or (at your option) any later version. | |
13 | * | |
14 | * This library is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
17 | * Lesser General Public License for more details. | |
18 | * | |
19 | * You should have received a copy of the GNU Lesser General Public | |
20 | * License along with this library; if not, write to the Free Software | |
21 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
22 | */ | |
23 | ||
24 | #define _GNU_SOURCE | |
988be9c1 CB |
25 | #include <errno.h> |
26 | #include <fcntl.h> | |
27 | #include <grp.h> | |
28 | #include <libgen.h> | |
3c16d0cb CB |
29 | #include <stdio.h> |
30 | #include <stdlib.h> | |
31 | #include <string.h> | |
988be9c1 CB |
32 | #include <unistd.h> |
33 | #include <sys/ioctl.h> | |
34 | #include <sys/stat.h> | |
0801b280 | 35 | #include <sys/wait.h> |
988be9c1 | 36 | #include <sys/types.h> |
6e0fa6a0 | 37 | #include <sys/vfs.h> |
3c16d0cb CB |
38 | |
39 | #include "log.h" | |
28d832c4 CB |
40 | #include "btrfs.h" |
41 | #include "rsync.h" | |
42 | #include "storage.h" | |
43 | #include "utils.h" | |
3c16d0cb | 44 | |
9a09badc | 45 | lxc_log_define(lxcbtrfs, lxc); |
3c16d0cb CB |
46 | |
47 | /* | |
48 | * Return the full path of objid under dirid. Let's say dirid is | |
49 | * /lxc/c1/rootfs, and objid is /lxc/c1/rootfs/a/b/c. Then we will | |
50 | * return a/b/c. If instead objid is for /lxc/c1/rootfs/a, we will | |
51 | * simply return a. | |
52 | */ | |
53 | char *get_btrfs_subvol_path(int fd, u64 dir_id, u64 objid, char *name, | |
54 | int name_len) | |
55 | { | |
56 | struct btrfs_ioctl_ino_lookup_args args; | |
57 | int ret, e; | |
58 | size_t len; | |
59 | char *retpath; | |
60 | ||
61 | memset(&args, 0, sizeof(args)); | |
62 | args.treeid = dir_id; | |
63 | args.objectid = objid; | |
64 | ||
65 | ret = ioctl(fd, BTRFS_IOC_INO_LOOKUP, &args); | |
66 | e = errno; | |
67 | if (ret) { | |
b103ceac | 68 | ERROR("Failed to lookup path for %llu %llu %s - %s\n", |
69 | (unsigned long long) dir_id, | |
3c16d0cb CB |
70 | (unsigned long long) objid, |
71 | name, strerror(e)); | |
72 | return NULL; | |
73 | } else | |
b103ceac | 74 | INFO("Got path for %llu %llu - %s\n", |
3c16d0cb CB |
75 | (unsigned long long) objid, (unsigned long long) dir_id, |
76 | name); | |
77 | ||
78 | if (args.name[0]) { | |
79 | /* | |
80 | * we're in a subdirectory of ref_tree, the kernel ioctl | |
81 | * puts a / in there for us | |
82 | */ | |
83 | len = strlen(args.name) + name_len + 2; | |
84 | retpath = malloc(len); | |
85 | if (!retpath) | |
86 | return NULL; | |
87 | strcpy(retpath, args.name); | |
88 | strcat(retpath, "/"); | |
89 | strncat(retpath, name, name_len); | |
90 | } else { | |
91 | /* we're at the root of ref_tree */ | |
92 | len = name_len + 1; | |
93 | retpath = malloc(len); | |
94 | if (!retpath) | |
95 | return NULL; | |
96 | *retpath = '\0'; | |
97 | strncat(retpath, name, name_len); | |
98 | } | |
99 | return retpath; | |
100 | } | |
101 | ||
102 | // | |
103 | // btrfs ops | |
104 | // | |
105 | ||
106 | int btrfs_list_get_path_rootid(int fd, u64 *treeid) | |
107 | { | |
108 | int ret; | |
109 | struct btrfs_ioctl_ino_lookup_args args; | |
110 | ||
111 | memset(&args, 0, sizeof(args)); | |
112 | args.objectid = BTRFS_FIRST_FREE_OBJECTID; | |
113 | ||
114 | ret = ioctl(fd, BTRFS_IOC_INO_LOOKUP, &args); | |
115 | if (ret < 0) { | |
116 | WARN("Warning: can't perform the search -%s\n", | |
117 | strerror(errno)); | |
118 | return ret; | |
119 | } | |
120 | *treeid = args.treeid; | |
121 | return 0; | |
122 | } | |
123 | ||
124 | bool is_btrfs_fs(const char *path) | |
125 | { | |
126 | int fd, ret; | |
127 | struct btrfs_ioctl_space_args sargs; | |
128 | ||
129 | // make sure this is a btrfs filesystem | |
130 | fd = open(path, O_RDONLY); | |
131 | if (fd < 0) | |
132 | return false; | |
133 | sargs.space_slots = 0; | |
134 | sargs.total_spaces = 0; | |
135 | ret = ioctl(fd, BTRFS_IOC_SPACE_INFO, &sargs); | |
136 | close(fd); | |
137 | if (ret < 0) | |
138 | return false; | |
139 | ||
140 | return true; | |
141 | } | |
142 | ||
6e0fa6a0 CB |
143 | /* |
144 | * Taken from btrfs toolsuite. Test if path is a subvolume. | |
145 | * return 0; path exists but it is not a subvolume | |
146 | * return 1; path exists and it is a subvolume | |
147 | * return < 0; error | |
148 | */ | |
149 | int is_btrfs_subvol(const char *path) | |
150 | { | |
151 | struct stat st; | |
152 | struct statfs stfs; | |
153 | int ret; | |
154 | ||
155 | ret = stat(path, &st); | |
156 | if (ret < 0) | |
157 | return -errno; | |
158 | ||
159 | if (st.st_ino != BTRFS_FIRST_FREE_OBJECTID || !S_ISDIR(st.st_mode)) | |
160 | return 0; | |
161 | ||
162 | ret = statfs(path, &stfs); | |
163 | if (ret < 0) | |
164 | return -errno; | |
165 | ||
166 | return stfs.f_type == BTRFS_SUPER_MAGIC; | |
167 | } | |
168 | ||
3d2ae1e2 | 169 | bool btrfs_detect(const char *path) |
3c16d0cb CB |
170 | { |
171 | struct stat st; | |
172 | int ret; | |
173 | ||
f7ac4459 | 174 | if (!strncmp(path, "btrfs:", 6)) |
3d2ae1e2 | 175 | return true; |
f7ac4459 | 176 | |
3c16d0cb | 177 | if (!is_btrfs_fs(path)) |
3d2ae1e2 | 178 | return false; |
3c16d0cb | 179 | |
f7ac4459 | 180 | /* make sure it's a subvolume */ |
3c16d0cb CB |
181 | ret = stat(path, &st); |
182 | if (ret < 0) | |
3d2ae1e2 | 183 | return false; |
3c16d0cb CB |
184 | |
185 | if (st.st_ino == 256 && S_ISDIR(st.st_mode)) | |
3d2ae1e2 | 186 | return true; |
3c16d0cb | 187 | |
3d2ae1e2 | 188 | return false; |
3c16d0cb CB |
189 | } |
190 | ||
191 | int btrfs_mount(struct bdev *bdev) | |
192 | { | |
193 | unsigned long mntflags; | |
3f88da0e | 194 | char *mntdata, *src; |
3c16d0cb CB |
195 | int ret; |
196 | ||
197 | if (strcmp(bdev->type, "btrfs")) | |
198 | return -22; | |
3f88da0e | 199 | |
3c16d0cb CB |
200 | if (!bdev->src || !bdev->dest) |
201 | return -22; | |
202 | ||
203 | if (parse_mntopts(bdev->mntopts, &mntflags, &mntdata) < 0) { | |
204 | free(mntdata); | |
205 | return -22; | |
206 | } | |
207 | ||
3f88da0e CB |
208 | src = lxc_storage_get_path(bdev->src, "btrfs"); |
209 | ||
210 | ret = mount(src, bdev->dest, "bind", MS_BIND | MS_REC | mntflags, mntdata); | |
3c16d0cb CB |
211 | free(mntdata); |
212 | return ret; | |
213 | } | |
214 | ||
215 | int btrfs_umount(struct bdev *bdev) | |
216 | { | |
217 | if (strcmp(bdev->type, "btrfs")) | |
218 | return -22; | |
3f88da0e | 219 | |
3c16d0cb CB |
220 | if (!bdev->src || !bdev->dest) |
221 | return -22; | |
3f88da0e | 222 | |
3c16d0cb CB |
223 | return umount(bdev->dest); |
224 | } | |
225 | ||
226 | static int btrfs_subvolume_create(const char *path) | |
227 | { | |
9edcd5ab CB |
228 | int ret, saved_errno; |
229 | struct btrfs_ioctl_vol_args args; | |
230 | char *p, *newfull; | |
231 | int fd = -1; | |
3c16d0cb | 232 | |
9edcd5ab | 233 | newfull = strdup(path); |
3c16d0cb | 234 | if (!newfull) { |
9edcd5ab CB |
235 | errno = ENOMEM; |
236 | return -ENOMEM; | |
3c16d0cb CB |
237 | } |
238 | ||
239 | p = strrchr(newfull, '/'); | |
240 | if (!p) { | |
3c16d0cb | 241 | free(newfull); |
9edcd5ab CB |
242 | errno = EINVAL; |
243 | return -EINVAL; | |
3c16d0cb CB |
244 | } |
245 | *p = '\0'; | |
246 | ||
247 | fd = open(newfull, O_RDONLY); | |
248 | if (fd < 0) { | |
dd49809f | 249 | free(newfull); |
9edcd5ab | 250 | return -errno; |
3c16d0cb CB |
251 | } |
252 | ||
253 | memset(&args, 0, sizeof(args)); | |
9edcd5ab CB |
254 | strncpy(args.name, p + 1, BTRFS_SUBVOL_NAME_MAX); |
255 | args.name[BTRFS_SUBVOL_NAME_MAX - 1] = 0; | |
256 | ||
3c16d0cb | 257 | ret = ioctl(fd, BTRFS_IOC_SUBVOL_CREATE, &args); |
9edcd5ab | 258 | saved_errno = errno; |
3c16d0cb | 259 | |
3c16d0cb | 260 | close(fd); |
dd49809f | 261 | free(newfull); |
9edcd5ab | 262 | errno = saved_errno; |
3c16d0cb CB |
263 | return ret; |
264 | } | |
265 | ||
988be9c1 | 266 | int btrfs_same_fs(const char *orig, const char *new) |
3c16d0cb CB |
267 | { |
268 | int fd_orig = -1, fd_new = -1, ret = -1; | |
269 | struct btrfs_ioctl_fs_info_args orig_args, new_args; | |
270 | ||
271 | fd_orig = open(orig, O_RDONLY); | |
272 | if (fd_orig < 0) { | |
273 | SYSERROR("Error opening original rootfs %s", orig); | |
274 | goto out; | |
275 | } | |
276 | ret = ioctl(fd_orig, BTRFS_IOC_FS_INFO, &orig_args); | |
277 | if (ret < 0) { | |
278 | SYSERROR("BTRFS_IOC_FS_INFO %s", orig); | |
279 | goto out; | |
280 | } | |
281 | ||
282 | fd_new = open(new, O_RDONLY); | |
283 | if (fd_new < 0) { | |
284 | SYSERROR("Error opening new container dir %s", new); | |
285 | ret = -1; | |
286 | goto out; | |
287 | } | |
288 | ret = ioctl(fd_new, BTRFS_IOC_FS_INFO, &new_args); | |
289 | if (ret < 0) { | |
290 | SYSERROR("BTRFS_IOC_FS_INFO %s", new); | |
291 | goto out; | |
292 | } | |
293 | ||
294 | if (strncmp(orig_args.fsid, new_args.fsid, BTRFS_FSID_SIZE) != 0) { | |
295 | ret = -1; | |
296 | goto out; | |
297 | } | |
298 | ret = 0; | |
299 | out: | |
300 | if (fd_new != -1) | |
301 | close(fd_new); | |
302 | if (fd_orig != -1) | |
303 | close(fd_orig); | |
304 | return ret; | |
305 | } | |
306 | ||
988be9c1 | 307 | int btrfs_snapshot(const char *orig, const char *new) |
3c16d0cb | 308 | { |
9edcd5ab CB |
309 | struct btrfs_ioctl_vol_args_v2 args; |
310 | char *newdir, *newname; | |
311 | char *newfull = NULL; | |
312 | int saved_errno = -1; | |
3c16d0cb | 313 | int fd = -1, fddst = -1, ret = -1; |
3c16d0cb CB |
314 | |
315 | newfull = strdup(new); | |
9edcd5ab | 316 | if (!newfull) |
3c16d0cb | 317 | goto out; |
9edcd5ab CB |
318 | |
319 | ret = rmdir(newfull); | |
320 | if (ret < 0 && errno != ENOENT) | |
3c16d0cb | 321 | goto out; |
9edcd5ab | 322 | |
3c16d0cb | 323 | newname = basename(newfull); |
3c16d0cb | 324 | fd = open(orig, O_RDONLY); |
9edcd5ab | 325 | if (fd < 0) |
3c16d0cb | 326 | goto out; |
9edcd5ab CB |
327 | |
328 | newdir = dirname(newfull); | |
3c16d0cb | 329 | fddst = open(newdir, O_RDONLY); |
9edcd5ab | 330 | if (fddst < 0) |
3c16d0cb | 331 | goto out; |
3c16d0cb CB |
332 | |
333 | memset(&args, 0, sizeof(args)); | |
334 | args.fd = fd; | |
335 | strncpy(args.name, newname, BTRFS_SUBVOL_NAME_MAX); | |
9edcd5ab CB |
336 | args.name[BTRFS_SUBVOL_NAME_MAX - 1] = 0; |
337 | ||
3c16d0cb | 338 | ret = ioctl(fddst, BTRFS_IOC_SNAP_CREATE_V2, &args); |
9edcd5ab | 339 | saved_errno = errno; |
3c16d0cb CB |
340 | |
341 | out: | |
342 | if (fddst != -1) | |
343 | close(fddst); | |
344 | if (fd != -1) | |
345 | close(fd); | |
346 | free(newfull); | |
9edcd5ab CB |
347 | |
348 | if (saved_errno >= 0) | |
349 | errno = saved_errno; | |
3c16d0cb CB |
350 | return ret; |
351 | } | |
352 | ||
e4a894d7 | 353 | int btrfs_snapshot_wrapper(void *data) |
3c16d0cb | 354 | { |
3f88da0e | 355 | char *src; |
3c16d0cb | 356 | struct rsync_data_char *arg = data; |
3f88da0e | 357 | |
3c16d0cb CB |
358 | if (setgid(0) < 0) { |
359 | ERROR("Failed to setgid to 0"); | |
360 | return -1; | |
361 | } | |
362 | if (setgroups(0, NULL) < 0) | |
363 | WARN("Failed to clear groups"); | |
9edcd5ab | 364 | |
3c16d0cb CB |
365 | if (setuid(0) < 0) { |
366 | ERROR("Failed to setuid to 0"); | |
367 | return -1; | |
368 | } | |
3f88da0e CB |
369 | |
370 | src = lxc_storage_get_path(arg->src, "btrfs"); | |
3f88da0e | 371 | return btrfs_snapshot(src, arg->dest); |
3c16d0cb CB |
372 | } |
373 | ||
374 | int btrfs_clonepaths(struct bdev *orig, struct bdev *new, const char *oldname, | |
375 | const char *cname, const char *oldpath, | |
376 | const char *lxcpath, int snap, uint64_t newsize, | |
377 | struct lxc_conf *conf) | |
378 | { | |
3f88da0e CB |
379 | char *src; |
380 | ||
3c16d0cb CB |
381 | if (!orig->dest || !orig->src) |
382 | return -1; | |
383 | ||
0801b280 CB |
384 | if (strcmp(orig->type, "btrfs") && snap) { |
385 | ERROR("btrfs snapshot from %s backing store is not supported", | |
386 | orig->type); | |
387 | return -1; | |
3c16d0cb CB |
388 | } |
389 | ||
0801b280 CB |
390 | new->src = lxc_string_join( |
391 | "/", | |
392 | (const char *[]){"btrfs:", *lxcpath != '/' ? lxcpath : ++lxcpath, | |
393 | cname, "rootfs", NULL}, | |
394 | false); | |
9edcd5ab CB |
395 | if (!new->src) { |
396 | ERROR("Failed to create new rootfs path"); | |
0801b280 | 397 | return -1; |
9edcd5ab | 398 | } |
b196516b | 399 | TRACE("Constructed new rootfs path \"%s\"", new->src); |
0801b280 | 400 | |
3f88da0e CB |
401 | src = lxc_storage_get_path(new->src, "btrfs"); |
402 | new->dest = strdup(src); | |
9edcd5ab CB |
403 | if (!new->dest) { |
404 | ERROR("Failed to duplicate string \"%s\"", src); | |
3c16d0cb | 405 | return -1; |
9edcd5ab | 406 | } |
3c16d0cb | 407 | |
9edcd5ab CB |
408 | if (orig->mntopts) { |
409 | new->mntopts = strdup(orig->mntopts); | |
410 | if (!new->mntopts) { | |
411 | ERROR("Failed to duplicate string \"%s\"", | |
412 | orig->mntopts); | |
413 | return -1; | |
414 | } | |
415 | } | |
3c16d0cb | 416 | |
b196516b CB |
417 | return 0; |
418 | } | |
45dd65e7 | 419 | |
b196516b CB |
420 | bool btrfs_create_clone(struct lxc_conf *conf, struct bdev *orig, |
421 | struct bdev *new, uint64_t newsize) | |
422 | { | |
dd49809f CB |
423 | int ret; |
424 | struct rsync_data data = {0, 0}; | |
425 | char cmd_output[MAXPATHLEN] = {0}; | |
3c16d0cb | 426 | |
9edcd5ab | 427 | ret = rmdir(new->dest); |
b196516b CB |
428 | if (ret < 0 && errno != ENOENT) |
429 | return false; | |
3c16d0cb | 430 | |
9edcd5ab | 431 | ret = btrfs_subvolume_create(new->dest); |
b196516b | 432 | if (ret < 0) { |
9edcd5ab | 433 | SYSERROR("Failed to create btrfs subvolume \"%s\"", new->dest); |
b196516b CB |
434 | return false; |
435 | } | |
436 | ||
dd49809f CB |
437 | /* rsync the contents from source to target */ |
438 | data.orig = orig; | |
439 | data.new = new; | |
440 | if (am_unpriv()) { | |
441 | ret = userns_exec_1(conf, lxc_rsync_exec_wrapper, &data, | |
442 | "lxc_rsync_exec_wrapper"); | |
b196516b | 443 | if (ret < 0) { |
dd49809f CB |
444 | ERROR("Failed to rsync from \"%s\" into \"%s\"", |
445 | orig->dest, new->dest); | |
b196516b CB |
446 | return false; |
447 | } | |
dd49809f | 448 | |
b196516b CB |
449 | return true; |
450 | } | |
451 | ||
dd49809f CB |
452 | ret = run_command(cmd_output, sizeof(cmd_output), |
453 | lxc_rsync_exec_wrapper, (void *)&data); | |
b196516b | 454 | if (ret < 0) { |
dd49809f CB |
455 | ERROR("Failed to rsync from \"%s\" into \"%s\": %s", orig->dest, |
456 | new->dest, cmd_output); | |
b196516b CB |
457 | return false; |
458 | } | |
459 | ||
b196516b CB |
460 | return true; |
461 | } | |
462 | ||
463 | bool btrfs_create_snapshot(struct lxc_conf *conf, struct bdev *orig, | |
53e50ae8 | 464 | struct bdev *new, uint64_t newsize) |
b196516b CB |
465 | { |
466 | int ret; | |
467 | ||
468 | ret = rmdir(new->dest); | |
469 | if (ret < 0 && errno != ENOENT) | |
470 | return false; | |
471 | ||
472 | if (am_unpriv()) { | |
473 | struct rsync_data_char args; | |
474 | ||
475 | args.src = orig->dest; | |
476 | args.dest = new->dest; | |
477 | ||
478 | ret = userns_exec_1(conf, btrfs_snapshot_wrapper, &args, | |
479 | "btrfs_snapshot_wrapper"); | |
480 | if (ret < 0) { | |
481 | ERROR("Failed to run \"btrfs_snapshot_wrapper\""); | |
482 | return false; | |
483 | } | |
484 | ||
485 | TRACE("Created btrfs snapshot \"%s\" from \"%s\"", new->dest, | |
486 | orig->dest); | |
487 | return true; | |
488 | } | |
489 | ||
490 | ret = btrfs_snapshot(orig->dest, new->dest); | |
491 | if (ret < 0) { | |
492 | SYSERROR("Failed to create btrfs snapshot \"%s\" from \"%s\"", | |
493 | new->dest, orig->dest); | |
494 | return false; | |
495 | } | |
496 | ||
497 | TRACE("Created btrfs snapshot \"%s\" from \"%s\"", new->dest, orig->dest); | |
498 | return true; | |
3c16d0cb CB |
499 | } |
500 | ||
501 | static int btrfs_do_destroy_subvol(const char *path) | |
502 | { | |
503 | int ret, fd = -1; | |
504 | struct btrfs_ioctl_vol_args args; | |
505 | char *p, *newfull = strdup(path); | |
506 | ||
507 | if (!newfull) { | |
508 | ERROR("Error: out of memory"); | |
509 | return -1; | |
510 | } | |
511 | ||
512 | p = strrchr(newfull, '/'); | |
513 | if (!p) { | |
514 | ERROR("bad path: %s", path); | |
515 | free(newfull); | |
516 | return -1; | |
517 | } | |
518 | *p = '\0'; | |
519 | ||
520 | fd = open(newfull, O_RDONLY); | |
521 | if (fd < 0) { | |
522 | SYSERROR("Error opening %s", newfull); | |
523 | free(newfull); | |
524 | return -1; | |
525 | } | |
526 | ||
527 | memset(&args, 0, sizeof(args)); | |
528 | strncpy(args.name, p+1, BTRFS_SUBVOL_NAME_MAX); | |
529 | args.name[BTRFS_SUBVOL_NAME_MAX-1] = 0; | |
530 | ret = ioctl(fd, BTRFS_IOC_SNAP_DESTROY, &args); | |
531 | INFO("btrfs: snapshot destroy ioctl returned %d for %s", ret, path); | |
532 | if (ret < 0 && errno == EPERM) | |
533 | ERROR("Is the rootfs mounted with -o user_subvol_rm_allowed?"); | |
534 | ||
535 | free(newfull); | |
536 | close(fd); | |
537 | return ret; | |
538 | } | |
539 | ||
540 | static int get_btrfs_tree_idx(struct my_btrfs_tree *tree, u64 id) | |
541 | { | |
542 | int i; | |
543 | if (!tree) | |
544 | return -1; | |
545 | for (i = 0; i < tree->num; i++) { | |
546 | if (tree->nodes[i].objid == id) | |
547 | return i; | |
548 | } | |
549 | return -1; | |
550 | } | |
551 | ||
552 | static struct my_btrfs_tree *create_my_btrfs_tree(u64 id, const char *path, | |
553 | int name_len) | |
554 | { | |
555 | struct my_btrfs_tree *tree; | |
556 | ||
557 | tree = malloc(sizeof(struct my_btrfs_tree)); | |
558 | if (!tree) | |
559 | return NULL; | |
560 | tree->nodes = malloc(sizeof(struct mytree_node)); | |
561 | if (!tree->nodes) { | |
562 | free(tree); | |
563 | return NULL; | |
564 | } | |
565 | tree->num = 1; | |
566 | tree->nodes[0].dirname = NULL; | |
567 | tree->nodes[0].name = strdup(path); | |
568 | if (!tree->nodes[0].name) { | |
569 | free(tree->nodes); | |
570 | free(tree); | |
571 | return NULL; | |
572 | } | |
573 | tree->nodes[0].parentid = 0; | |
574 | tree->nodes[0].objid = id; | |
575 | return tree; | |
576 | } | |
577 | ||
578 | static bool update_tree_node(struct mytree_node *n, u64 id, u64 parent, | |
579 | char *name, int name_len, char *dirname) | |
580 | { | |
581 | if (id) | |
582 | n->objid = id; | |
583 | if (parent) | |
584 | n->parentid = parent; | |
585 | if (name) { | |
586 | n->name = malloc(name_len + 1); | |
587 | if (!n->name) | |
588 | return false; | |
589 | strncpy(n->name, name, name_len); | |
590 | n->name[name_len] = '\0'; | |
591 | } | |
592 | if (dirname) { | |
593 | n->dirname = malloc(strlen(dirname) + 1); | |
594 | if (!n->dirname) { | |
595 | free(n->name); | |
596 | return false; | |
597 | } | |
598 | strcpy(n->dirname, dirname); | |
599 | } | |
600 | return true; | |
601 | } | |
602 | ||
603 | static bool add_btrfs_tree_node(struct my_btrfs_tree *tree, u64 id, u64 parent, | |
604 | char *name, int name_len, char *dirname) | |
605 | { | |
606 | struct mytree_node *tmp; | |
607 | ||
608 | int i = get_btrfs_tree_idx(tree, id); | |
609 | if (i != -1) | |
610 | return update_tree_node(&tree->nodes[i], id, parent, name, | |
611 | name_len, dirname); | |
612 | ||
613 | tmp = realloc(tree->nodes, (tree->num+1) * sizeof(struct mytree_node)); | |
614 | if (!tmp) | |
615 | return false; | |
616 | tree->nodes = tmp; | |
617 | memset(&tree->nodes[tree->num], 0, sizeof(struct mytree_node)); | |
618 | if (!update_tree_node(&tree->nodes[tree->num], id, parent, name, | |
619 | name_len, dirname)) | |
620 | return false; | |
621 | tree->num++; | |
622 | return true; | |
623 | } | |
624 | ||
625 | static void free_btrfs_tree(struct my_btrfs_tree *tree) | |
626 | { | |
627 | int i; | |
628 | if (!tree) | |
629 | return; | |
630 | for (i = 0; i < tree->num; i++) { | |
631 | free(tree->nodes[i].name); | |
632 | free(tree->nodes[i].dirname); | |
633 | } | |
634 | free(tree->nodes); | |
635 | free(tree); | |
636 | } | |
637 | ||
638 | /* | |
639 | * Given a @tree of subvolumes under @path, ask btrfs to remove each | |
640 | * subvolume | |
641 | */ | |
642 | static bool do_remove_btrfs_children(struct my_btrfs_tree *tree, u64 root_id, | |
643 | const char *path) | |
644 | { | |
645 | int i; | |
646 | char *newpath; | |
647 | size_t len; | |
648 | ||
649 | for (i = 0; i < tree->num; i++) { | |
650 | if (tree->nodes[i].parentid == root_id) { | |
651 | if (!tree->nodes[i].dirname) { | |
652 | WARN("Odd condition: child objid with no name under %s\n", path); | |
653 | continue; | |
654 | } | |
655 | len = strlen(path) + strlen(tree->nodes[i].dirname) + 2; | |
656 | newpath = malloc(len); | |
657 | if (!newpath) { | |
658 | ERROR("Out of memory"); | |
659 | return false; | |
660 | } | |
661 | snprintf(newpath, len, "%s/%s", path, tree->nodes[i].dirname); | |
662 | if (!do_remove_btrfs_children(tree, tree->nodes[i].objid, newpath)) { | |
663 | ERROR("Failed to prune %s\n", tree->nodes[i].name); | |
664 | free(newpath); | |
665 | return false; | |
666 | } | |
667 | if (btrfs_do_destroy_subvol(newpath) != 0) { | |
668 | ERROR("Failed to remove %s\n", newpath); | |
669 | free(newpath); | |
670 | return false; | |
671 | } | |
672 | free(newpath); | |
673 | } | |
674 | } | |
675 | return true; | |
676 | } | |
677 | ||
678 | static int btrfs_recursive_destroy(const char *path) | |
679 | { | |
680 | u64 root_id; | |
681 | int fd; | |
682 | struct btrfs_ioctl_search_args args; | |
683 | struct btrfs_ioctl_search_key *sk = &args.key; | |
21e019c2 | 684 | struct btrfs_ioctl_search_header sh; |
3c16d0cb CB |
685 | struct btrfs_root_ref *ref; |
686 | struct my_btrfs_tree *tree; | |
58232f8c | 687 | int ret, e, i; |
3c16d0cb CB |
688 | unsigned long off = 0; |
689 | int name_len; | |
690 | char *name; | |
691 | char *tmppath; | |
21e019c2 | 692 | u64 dir_id; |
3c16d0cb CB |
693 | |
694 | fd = open(path, O_RDONLY); | |
695 | if (fd < 0) { | |
696 | ERROR("Failed to open %s\n", path); | |
697 | return -1; | |
698 | } | |
699 | ||
700 | if (btrfs_list_get_path_rootid(fd, &root_id)) { | |
58232f8c | 701 | e = errno; |
3c16d0cb | 702 | close(fd); |
58232f8c | 703 | if (e == EPERM || e == EACCES) { |
3c16d0cb CB |
704 | WARN("Will simply try removing"); |
705 | goto ignore_search; | |
706 | } | |
707 | ||
708 | return -1; | |
709 | } | |
710 | ||
711 | tree = create_my_btrfs_tree(root_id, path, strlen(path)); | |
712 | if (!tree) { | |
713 | ERROR("Out of memory\n"); | |
714 | close(fd); | |
715 | return -1; | |
716 | } | |
717 | /* Walk all subvols looking for any under this id */ | |
718 | memset(&args, 0, sizeof(args)); | |
719 | ||
720 | /* search in the tree of tree roots */ | |
721 | sk->tree_id = 1; | |
722 | ||
723 | sk->max_type = BTRFS_ROOT_REF_KEY; | |
724 | sk->min_type = BTRFS_ROOT_ITEM_KEY; | |
725 | sk->min_objectid = 0; | |
726 | sk->max_objectid = (u64)-1; | |
727 | sk->max_offset = (u64)-1; | |
728 | sk->min_offset = 0; | |
729 | sk->max_transid = (u64)-1; | |
730 | sk->nr_items = 4096; | |
731 | ||
732 | while(1) { | |
733 | ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args); | |
58232f8c | 734 | e = errno; |
3c16d0cb CB |
735 | if (ret < 0) { |
736 | close(fd); | |
3c16d0cb | 737 | free_btrfs_tree(tree); |
58232f8c | 738 | if (e == EPERM || e == EACCES) { |
8ba6dc5e OF |
739 | WARN("Warn: can't perform the search under %s. Will simply try removing", path); |
740 | goto ignore_search; | |
741 | } | |
742 | ||
743 | ERROR("Error: can't perform the search under %s\n", path); | |
3c16d0cb CB |
744 | return -1; |
745 | } | |
746 | if (sk->nr_items == 0) | |
747 | break; | |
748 | ||
749 | off = 0; | |
750 | for (i = 0; i < sk->nr_items; i++) { | |
21e019c2 TT |
751 | memcpy(&sh, args.buf + off, sizeof(sh)); |
752 | off += sizeof(sh); | |
3c16d0cb CB |
753 | /* |
754 | * A backref key with the name and dirid of the parent | |
755 | * comes followed by the reoot ref key which has the | |
756 | * name of the child subvol in question. | |
757 | */ | |
21e019c2 | 758 | if (sh.objectid != root_id && sh.type == BTRFS_ROOT_BACKREF_KEY) { |
3c16d0cb | 759 | ref = (struct btrfs_root_ref *)(args.buf + off); |
21e019c2 | 760 | name_len = btrfs_stack_root_ref_name_len(ref); |
3c16d0cb | 761 | name = (char *)(ref + 1); |
21e019c2 TT |
762 | dir_id = btrfs_stack_root_ref_dirid(ref); |
763 | tmppath = get_btrfs_subvol_path(fd, sh.offset, | |
764 | dir_id, name, name_len); | |
765 | if (!add_btrfs_tree_node(tree, sh.objectid, | |
766 | sh.offset, name, | |
3c16d0cb CB |
767 | name_len, tmppath)) { |
768 | ERROR("Out of memory"); | |
769 | free_btrfs_tree(tree); | |
770 | free(tmppath); | |
771 | close(fd); | |
772 | return -1; | |
773 | } | |
774 | free(tmppath); | |
775 | } | |
21e019c2 | 776 | off += sh.len; |
3c16d0cb CB |
777 | |
778 | /* | |
779 | * record the mins in sk so we can make sure the | |
780 | * next search doesn't repeat this root | |
781 | */ | |
21e019c2 TT |
782 | sk->min_objectid = sh.objectid; |
783 | sk->min_type = sh.type; | |
784 | sk->min_offset = sh.offset; | |
3c16d0cb CB |
785 | } |
786 | sk->nr_items = 4096; | |
787 | sk->min_offset++; | |
788 | if (!sk->min_offset) | |
789 | sk->min_type++; | |
790 | else | |
791 | continue; | |
792 | ||
793 | if (sk->min_type > BTRFS_ROOT_BACKREF_KEY) { | |
794 | sk->min_type = BTRFS_ROOT_ITEM_KEY; | |
795 | sk->min_objectid++; | |
796 | } else | |
797 | continue; | |
798 | ||
799 | if (sk->min_objectid >= sk->max_objectid) | |
800 | break; | |
801 | } | |
802 | close(fd); | |
803 | ||
804 | /* now actually remove them */ | |
805 | ||
806 | if (!do_remove_btrfs_children(tree, root_id, path)) { | |
807 | free_btrfs_tree(tree); | |
808 | ERROR("failed pruning\n"); | |
809 | return -1; | |
810 | } | |
811 | ||
812 | free_btrfs_tree(tree); | |
813 | /* All child subvols have been removed, now remove this one */ | |
814 | ignore_search: | |
815 | return btrfs_do_destroy_subvol(path); | |
816 | } | |
817 | ||
818 | bool btrfs_try_remove_subvol(const char *path) | |
819 | { | |
820 | if (!btrfs_detect(path)) | |
821 | return false; | |
3f88da0e | 822 | |
3c16d0cb CB |
823 | return btrfs_recursive_destroy(path) == 0; |
824 | } | |
825 | ||
826 | int btrfs_destroy(struct bdev *orig) | |
827 | { | |
3f88da0e CB |
828 | char *src; |
829 | ||
830 | src = lxc_storage_get_path(orig->src, "btrfs"); | |
831 | ||
832 | return btrfs_recursive_destroy(src); | |
3c16d0cb CB |
833 | } |
834 | ||
835 | int btrfs_create(struct bdev *bdev, const char *dest, const char *n, | |
836 | struct bdev_specs *specs) | |
837 | { | |
3f88da0e CB |
838 | int ret; |
839 | size_t len; | |
840 | ||
841 | len = strlen(dest) + 1; | |
842 | /* strlen("btrfs:") */ | |
843 | len += 6; | |
844 | bdev->src = malloc(len); | |
dd49809f CB |
845 | if (!bdev->src) { |
846 | ERROR("Failed to allocate memory"); | |
3f88da0e | 847 | return -1; |
dd49809f | 848 | } |
3f88da0e CB |
849 | |
850 | ret = snprintf(bdev->src, len, "btrfs:%s", dest); | |
dd49809f CB |
851 | if (ret < 0 || (size_t)ret >= len) { |
852 | ERROR("Failed to create string"); | |
3f88da0e | 853 | return -1; |
dd49809f | 854 | } |
3f88da0e | 855 | |
3c16d0cb | 856 | bdev->dest = strdup(dest); |
dd49809f CB |
857 | if (!bdev->dest) { |
858 | ERROR("Failed to duplicate string \"%s\"", dest); | |
3c16d0cb | 859 | return -1; |
dd49809f | 860 | } |
3f88da0e | 861 | |
dd49809f CB |
862 | ret = btrfs_subvolume_create(bdev->dest); |
863 | if (ret < 0) { | |
864 | SYSERROR("Failed to create btrfs subvolume \"%s\"", bdev->dest); | |
865 | } | |
866 | ||
867 | return ret; | |
3c16d0cb | 868 | } |