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btrfs-progs: test/fsck/021: Cleanup custom check by overriding check_image
[btrfs-progs-unstable/devel.git] / utils.c
blob524f463d31406b1005a250ef7d31264d556fcdb0
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 * Copyright (C) 2008 Morey Roof. All rights reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public
7 * License v2 as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public
15 * License along with this program; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 021110-1307, USA.
18 */
19
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <sys/ioctl.h>
24 #include <sys/mount.h>
25 #include <sys/types.h>
26 #include <sys/stat.h>
27 #include <sys/sysinfo.h>
28 #include <uuid/uuid.h>
29 #include <fcntl.h>
30 #include <unistd.h>
31 #include <mntent.h>
32 #include <ctype.h>
33 #include <linux/loop.h>
34 #include <linux/major.h>
35 #include <linux/kdev_t.h>
36 #include <limits.h>
37 #include <blkid/blkid.h>
38 #include <sys/vfs.h>
39 #include <sys/statfs.h>
40 #include <linux/magic.h>
41 #include <getopt.h>
42
43 #include "kerncompat.h"
44 #include "radix-tree.h"
45 #include "ctree.h"
46 #include "disk-io.h"
47 #include "transaction.h"
48 #include "crc32c.h"
49 #include "utils.h"
50 #include "volumes.h"
51 #include "ioctl.h"
52 #include "commands.h"
53 #include "mkfs/common.h"
54
55 #ifndef BLKDISCARD
56 #define BLKDISCARD _IO(0x12,119)
57 #endif
58
59 static int btrfs_scan_done = 0;
60
61 static int rand_seed_initlized = 0;
62 static unsigned short rand_seed[3];
63
64 struct btrfs_config bconf;
65
66 /*
67 * Discard the given range in one go
68 */
69 static int discard_range(int fd, u64 start, u64 len)
70 {
71 u64 range[2] = { start, len };
72
73 if (ioctl(fd, BLKDISCARD, &range) < 0)
74 return errno;
75 return 0;
76 }
77
78 /*
79 * Discard blocks in the given range in 1G chunks, the process is interruptible
80 */
81 static int discard_blocks(int fd, u64 start, u64 len)
82 {
83 while (len > 0) {
84 /* 1G granularity */
85 u64 chunk_size = min_t(u64, len, SZ_1G);
86 int ret;
87
88 ret = discard_range(fd, start, chunk_size);
89 if (ret)
90 return ret;
91 len -= chunk_size;
92 start += chunk_size;
93 }
94
95 return 0;
96 }
97
98 int test_uuid_unique(char *fs_uuid)
99 {
100 int unique = 1;
101 blkid_dev_iterate iter = NULL;
102 blkid_dev dev = NULL;
103 blkid_cache cache = NULL;
104
105 if (blkid_get_cache(&cache, NULL) < 0) {
106 printf("ERROR: lblkid cache get failed\n");
107 return 1;
108 }
109 blkid_probe_all(cache);
110 iter = blkid_dev_iterate_begin(cache);
111 blkid_dev_set_search(iter, "UUID", fs_uuid);
112
113 while (blkid_dev_next(iter, &dev) == 0) {
114 dev = blkid_verify(cache, dev);
115 if (dev) {
116 unique = 0;
117 break;
118 }
119 }
120
121 blkid_dev_iterate_end(iter);
122 blkid_put_cache(cache);
123
124 return unique;
125 }
126
127 u64 btrfs_device_size(int fd, struct stat *st)
128 {
129 u64 size;
130 if (S_ISREG(st->st_mode)) {
131 return st->st_size;
132 }
133 if (!S_ISBLK(st->st_mode)) {
134 return 0;
135 }
136 if (ioctl(fd, BLKGETSIZE64, &size) >= 0) {
137 return size;
138 }
139 return 0;
140 }
141
142 static int zero_blocks(int fd, off_t start, size_t len)
143 {
144 char *buf = malloc(len);
145 int ret = 0;
146 ssize_t written;
147
148 if (!buf)
149 return -ENOMEM;
150 memset(buf, 0, len);
151 written = pwrite(fd, buf, len, start);
152 if (written != len)
153 ret = -EIO;
154 free(buf);
155 return ret;
156 }
157
158 #define ZERO_DEV_BYTES SZ_2M
159
160 /* don't write outside the device by clamping the region to the device size */
161 static int zero_dev_clamped(int fd, off_t start, ssize_t len, u64 dev_size)
162 {
163 off_t end = max(start, start + len);
164
165 #ifdef __sparc__
166 /* and don't overwrite the disk labels on sparc */
167 start = max(start, 1024);
168 end = max(end, 1024);
169 #endif
170
171 start = min_t(u64, start, dev_size);
172 end = min_t(u64, end, dev_size);
173
174 return zero_blocks(fd, start, end - start);
175 }
176
177 int btrfs_add_to_fsid(struct btrfs_trans_handle *trans,
178 struct btrfs_root *root, int fd, const char *path,
179 u64 device_total_bytes, u32 io_width, u32 io_align,
180 u32 sectorsize)
181 {
182 struct btrfs_super_block *disk_super;
183 struct btrfs_fs_info *fs_info = root->fs_info;
184 struct btrfs_super_block *super = fs_info->super_copy;
185 struct btrfs_device *device;
186 struct btrfs_dev_item *dev_item;
187 char *buf = NULL;
188 u64 fs_total_bytes;
189 u64 num_devs;
190 int ret;
191
192 device_total_bytes = (device_total_bytes / sectorsize) * sectorsize;
193
194 device = calloc(1, sizeof(*device));
195 if (!device) {
196 ret = -ENOMEM;
197 goto out;
198 }
199 buf = calloc(1, sectorsize);
200 if (!buf) {
201 ret = -ENOMEM;
202 goto out;
203 }
204
205 disk_super = (struct btrfs_super_block *)buf;
206 dev_item = &disk_super->dev_item;
207
208 uuid_generate(device->uuid);
209 device->devid = 0;
210 device->type = 0;
211 device->io_width = io_width;
212 device->io_align = io_align;
213 device->sector_size = sectorsize;
214 device->fd = fd;
215 device->writeable = 1;
216 device->total_bytes = device_total_bytes;
217 device->bytes_used = 0;
218 device->total_ios = 0;
219 device->dev_root = fs_info->dev_root;
220 device->name = strdup(path);
221 if (!device->name) {
222 ret = -ENOMEM;
223 goto out;
224 }
225
226 INIT_LIST_HEAD(&device->dev_list);
227 ret = btrfs_add_device(trans, fs_info, device);
228 if (ret)
229 goto out;
230
231 fs_total_bytes = btrfs_super_total_bytes(super) + device_total_bytes;
232 btrfs_set_super_total_bytes(super, fs_total_bytes);
233
234 num_devs = btrfs_super_num_devices(super) + 1;
235 btrfs_set_super_num_devices(super, num_devs);
236
237 memcpy(disk_super, super, sizeof(*disk_super));
238
239 btrfs_set_super_bytenr(disk_super, BTRFS_SUPER_INFO_OFFSET);
240 btrfs_set_stack_device_id(dev_item, device->devid);
241 btrfs_set_stack_device_type(dev_item, device->type);
242 btrfs_set_stack_device_io_align(dev_item, device->io_align);
243 btrfs_set_stack_device_io_width(dev_item, device->io_width);
244 btrfs_set_stack_device_sector_size(dev_item, device->sector_size);
245 btrfs_set_stack_device_total_bytes(dev_item, device->total_bytes);
246 btrfs_set_stack_device_bytes_used(dev_item, device->bytes_used);
247 memcpy(&dev_item->uuid, device->uuid, BTRFS_UUID_SIZE);
248
249 ret = pwrite(fd, buf, sectorsize, BTRFS_SUPER_INFO_OFFSET);
250 BUG_ON(ret != sectorsize);
251
252 free(buf);
253 list_add(&device->dev_list, &fs_info->fs_devices->devices);
254 device->fs_devices = fs_info->fs_devices;
255 return 0;
256
257 out:
258 free(device);
259 free(buf);
260 return ret;
261 }
262
263 static int btrfs_wipe_existing_sb(int fd)
264 {
265 const char *off = NULL;
266 size_t len = 0;
267 loff_t offset;
268 char buf[BUFSIZ];
269 int ret = 0;
270 blkid_probe pr = NULL;
271
272 pr = blkid_new_probe();
273 if (!pr)
274 return -1;
275
276 if (blkid_probe_set_device(pr, fd, 0, 0)) {
277 ret = -1;
278 goto out;
279 }
280
281 ret = blkid_probe_lookup_value(pr, "SBMAGIC_OFFSET", &off, NULL);
282 if (!ret)
283 ret = blkid_probe_lookup_value(pr, "SBMAGIC", NULL, &len);
284
285 if (ret || len == 0 || off == NULL) {
286 /*
287 * If lookup fails, the probe did not find any values, eg. for
288 * a file image or a loop device. Soft error.
289 */
290 ret = 1;
291 goto out;
292 }
293
294 offset = strtoll(off, NULL, 10);
295 if (len > sizeof(buf))
296 len = sizeof(buf);
297
298 memset(buf, 0, len);
299 ret = pwrite(fd, buf, len, offset);
300 if (ret < 0) {
301 error("cannot wipe existing superblock: %s", strerror(errno));
302 ret = -1;
303 } else if (ret != len) {
304 error("cannot wipe existing superblock: wrote %d of %zd", ret, len);
305 ret = -1;
306 }
307 fsync(fd);
308
309 out:
310 blkid_free_probe(pr);
311 return ret;
312 }
313
314 int btrfs_prepare_device(int fd, const char *file, u64 *block_count_ret,
315 u64 max_block_count, unsigned opflags)
316 {
317 u64 block_count;
318 struct stat st;
319 int i, ret;
320
321 ret = fstat(fd, &st);
322 if (ret < 0) {
323 error("unable to stat %s: %s", file, strerror(errno));
324 return 1;
325 }
326
327 block_count = btrfs_device_size(fd, &st);
328 if (block_count == 0) {
329 error("unable to determine size of %s", file);
330 return 1;
331 }
332 if (max_block_count)
333 block_count = min(block_count, max_block_count);
334
335 if (opflags & PREP_DEVICE_DISCARD) {
336 /*
337 * We intentionally ignore errors from the discard ioctl. It
338 * is not necessary for the mkfs functionality but just an
339 * optimization.
340 */
341 if (discard_range(fd, 0, 0) == 0) {
342 if (opflags & PREP_DEVICE_VERBOSE)
343 printf("Performing full device TRIM %s (%s) ...\n",
344 file, pretty_size(block_count));
345 discard_blocks(fd, 0, block_count);
346 }
347 }
348
349 ret = zero_dev_clamped(fd, 0, ZERO_DEV_BYTES, block_count);
350 for (i = 0 ; !ret && i < BTRFS_SUPER_MIRROR_MAX; i++)
351 ret = zero_dev_clamped(fd, btrfs_sb_offset(i),
352 BTRFS_SUPER_INFO_SIZE, block_count);
353 if (!ret && (opflags & PREP_DEVICE_ZERO_END))
354 ret = zero_dev_clamped(fd, block_count - ZERO_DEV_BYTES,
355 ZERO_DEV_BYTES, block_count);
356
357 if (ret < 0) {
358 error("failed to zero device '%s': %s", file, strerror(-ret));
359 return 1;
360 }
361
362 ret = btrfs_wipe_existing_sb(fd);
363 if (ret < 0) {
364 error("cannot wipe superblocks on %s", file);
365 return 1;
366 }
367
368 *block_count_ret = block_count;
369 return 0;
370 }
371
372 int btrfs_make_root_dir(struct btrfs_trans_handle *trans,
373 struct btrfs_root *root, u64 objectid)
374 {
375 int ret;
376 struct btrfs_inode_item inode_item;
377 time_t now = time(NULL);
378
379 memset(&inode_item, 0, sizeof(inode_item));
380 btrfs_set_stack_inode_generation(&inode_item, trans->transid);
381 btrfs_set_stack_inode_size(&inode_item, 0);
382 btrfs_set_stack_inode_nlink(&inode_item, 1);
383 btrfs_set_stack_inode_nbytes(&inode_item, root->fs_info->nodesize);
384 btrfs_set_stack_inode_mode(&inode_item, S_IFDIR | 0755);
385 btrfs_set_stack_timespec_sec(&inode_item.atime, now);
386 btrfs_set_stack_timespec_nsec(&inode_item.atime, 0);
387 btrfs_set_stack_timespec_sec(&inode_item.ctime, now);
388 btrfs_set_stack_timespec_nsec(&inode_item.ctime, 0);
389 btrfs_set_stack_timespec_sec(&inode_item.mtime, now);
390 btrfs_set_stack_timespec_nsec(&inode_item.mtime, 0);
391 btrfs_set_stack_timespec_sec(&inode_item.otime, now);
392 btrfs_set_stack_timespec_nsec(&inode_item.otime, 0);
393
394 if (root->fs_info->tree_root == root)
395 btrfs_set_super_root_dir(root->fs_info->super_copy, objectid);
396
397 ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
398 if (ret)
399 goto error;
400
401 ret = btrfs_insert_inode_ref(trans, root, "..", 2, objectid, objectid, 0);
402 if (ret)
403 goto error;
404
405 btrfs_set_root_dirid(&root->root_item, objectid);
406 ret = 0;
407 error:
408 return ret;
409 }
410
411 /*
412 * checks if a path is a block device node
413 * Returns negative errno on failure, otherwise
414 * returns 1 for blockdev, 0 for not-blockdev
415 */
416 int is_block_device(const char *path)
417 {
418 struct stat statbuf;
419
420 if (stat(path, &statbuf) < 0)
421 return -errno;
422
423 return !!S_ISBLK(statbuf.st_mode);
424 }
425
426 /*
427 * check if given path is a mount point
428 * return 1 if yes. 0 if no. -1 for error
429 */
430 int is_mount_point(const char *path)
431 {
432 FILE *f;
433 struct mntent *mnt;
434 int ret = 0;
435
436 f = setmntent("/proc/self/mounts", "r");
437 if (f == NULL)
438 return -1;
439
440 while ((mnt = getmntent(f)) != NULL) {
441 if (strcmp(mnt->mnt_dir, path))
442 continue;
443 ret = 1;
444 break;
445 }
446 endmntent(f);
447 return ret;
448 }
449
450 static int is_reg_file(const char *path)
451 {
452 struct stat statbuf;
453
454 if (stat(path, &statbuf) < 0)
455 return -errno;
456 return S_ISREG(statbuf.st_mode);
457 }
458
459 /*
460 * This function checks if the given input parameter is
461 * an uuid or a path
462 * return <0 : some error in the given input
463 * return BTRFS_ARG_UNKNOWN: unknown input
464 * return BTRFS_ARG_UUID: given input is uuid
465 * return BTRFS_ARG_MNTPOINT: given input is path
466 * return BTRFS_ARG_REG: given input is regular file
467 * return BTRFS_ARG_BLKDEV: given input is block device
468 */
469 int check_arg_type(const char *input)
470 {
471 uuid_t uuid;
472 char path[PATH_MAX];
473
474 if (!input)
475 return -EINVAL;
476
477 if (realpath(input, path)) {
478 if (is_block_device(path) == 1)
479 return BTRFS_ARG_BLKDEV;
480
481 if (is_mount_point(path) == 1)
482 return BTRFS_ARG_MNTPOINT;
483
484 if (is_reg_file(path))
485 return BTRFS_ARG_REG;
486
487 return BTRFS_ARG_UNKNOWN;
488 }
489
490 if (strlen(input) == (BTRFS_UUID_UNPARSED_SIZE - 1) &&
491 !uuid_parse(input, uuid))
492 return BTRFS_ARG_UUID;
493
494 return BTRFS_ARG_UNKNOWN;
495 }
496
497 /*
498 * Find the mount point for a mounted device.
499 * On success, returns 0 with mountpoint in *mp.
500 * On failure, returns -errno (not mounted yields -EINVAL)
501 * Is noisy on failures, expects to be given a mounted device.
502 */
503 int get_btrfs_mount(const char *dev, char *mp, size_t mp_size)
504 {
505 int ret;
506 int fd = -1;
507
508 ret = is_block_device(dev);
509 if (ret <= 0) {
510 if (!ret) {
511 error("not a block device: %s", dev);
512 ret = -EINVAL;
513 } else {
514 error("cannot check %s: %s", dev, strerror(-ret));
515 }
516 goto out;
517 }
518
519 fd = open(dev, O_RDONLY);
520 if (fd < 0) {
521 ret = -errno;
522 error("cannot open %s: %s", dev, strerror(errno));
523 goto out;
524 }
525
526 ret = check_mounted_where(fd, dev, mp, mp_size, NULL);
527 if (!ret) {
528 ret = -EINVAL;
529 } else { /* mounted, all good */
530 ret = 0;
531 }
532 out:
533 if (fd != -1)
534 close(fd);
535 return ret;
536 }
537
538 /*
539 * Given a pathname, return a filehandle to:
540 * the original pathname or,
541 * if the pathname is a mounted btrfs device, to its mountpoint.
542 *
543 * On error, return -1, errno should be set.
544 */
545 int open_path_or_dev_mnt(const char *path, DIR **dirstream, int verbose)
546 {
547 char mp[PATH_MAX];
548 int ret;
549
550 if (is_block_device(path)) {
551 ret = get_btrfs_mount(path, mp, sizeof(mp));
552 if (ret < 0) {
553 /* not a mounted btrfs dev */
554 error_on(verbose, "'%s' is not a mounted btrfs device",
555 path);
556 errno = EINVAL;
557 return -1;
558 }
559 ret = open_file_or_dir(mp, dirstream);
560 error_on(verbose && ret < 0, "can't access '%s': %s",
561 path, strerror(errno));
562 } else {
563 ret = btrfs_open_dir(path, dirstream, 1);
564 }
565
566 return ret;
567 }
568
569 /*
570 * Do the following checks before calling open_file_or_dir():
571 * 1: path is in a btrfs filesystem
572 * 2: path is a directory if dir_only is 1
573 */
574 int btrfs_open(const char *path, DIR **dirstream, int verbose, int dir_only)
575 {
576 struct statfs stfs;
577 struct stat st;
578 int ret;
579
580 if (statfs(path, &stfs) != 0) {
581 error_on(verbose, "cannot access '%s': %s", path,
582 strerror(errno));
583 return -1;
584 }
585
586 if (stfs.f_type != BTRFS_SUPER_MAGIC) {
587 error_on(verbose, "not a btrfs filesystem: %s", path);
588 return -2;
589 }
590
591 if (stat(path, &st) != 0) {
592 error_on(verbose, "cannot access '%s': %s", path,
593 strerror(errno));
594 return -1;
595 }
596
597 if (dir_only && !S_ISDIR(st.st_mode)) {
598 error_on(verbose, "not a directory: %s", path);
599 return -3;
600 }
601
602 ret = open_file_or_dir(path, dirstream);
603 if (ret < 0) {
604 error_on(verbose, "cannot access '%s': %s", path,
605 strerror(errno));
606 }
607
608 return ret;
609 }
610
611 int btrfs_open_dir(const char *path, DIR **dirstream, int verbose)
612 {
613 return btrfs_open(path, dirstream, verbose, 1);
614 }
615
616 int btrfs_open_file_or_dir(const char *path, DIR **dirstream, int verbose)
617 {
618 return btrfs_open(path, dirstream, verbose, 0);
619 }
620
621 /* checks if a device is a loop device */
622 static int is_loop_device (const char* device) {
623 struct stat statbuf;
624
625 if(stat(device, &statbuf) < 0)
626 return -errno;
627
628 return (S_ISBLK(statbuf.st_mode) &&
629 MAJOR(statbuf.st_rdev) == LOOP_MAJOR);
630 }
631
632 /*
633 * Takes a loop device path (e.g. /dev/loop0) and returns
634 * the associated file (e.g. /images/my_btrfs.img) using
635 * loopdev API
636 */
637 static int resolve_loop_device_with_loopdev(const char* loop_dev, char* loop_file)
638 {
639 int fd;
640 int ret;
641 struct loop_info64 lo64;
642
643 fd = open(loop_dev, O_RDONLY | O_NONBLOCK);
644 if (fd < 0)
645 return -errno;
646 ret = ioctl(fd, LOOP_GET_STATUS64, &lo64);
647 if (ret < 0) {
648 ret = -errno;
649 goto out;
650 }
651
652 memcpy(loop_file, lo64.lo_file_name, sizeof(lo64.lo_file_name));
653 loop_file[sizeof(lo64.lo_file_name)] = 0;
654
655 out:
656 close(fd);
657
658 return ret;
659 }
660
661 /* Takes a loop device path (e.g. /dev/loop0) and returns
662 * the associated file (e.g. /images/my_btrfs.img) */
663 static int resolve_loop_device(const char* loop_dev, char* loop_file,
664 int max_len)
665 {
666 int ret;
667 FILE *f;
668 char fmt[20];
669 char p[PATH_MAX];
670 char real_loop_dev[PATH_MAX];
671
672 if (!realpath(loop_dev, real_loop_dev))
673 return -errno;
674 snprintf(p, PATH_MAX, "/sys/block/%s/loop/backing_file", strrchr(real_loop_dev, '/'));
675 if (!(f = fopen(p, "r"))) {
676 if (errno == ENOENT)
677 /*
678 * It's possibly a partitioned loop device, which is
679 * resolvable with loopdev API.
680 */
681 return resolve_loop_device_with_loopdev(loop_dev, loop_file);
682 return -errno;
683 }
684
685 snprintf(fmt, 20, "%%%i[^\n]", max_len-1);
686 ret = fscanf(f, fmt, loop_file);
687 fclose(f);
688 if (ret == EOF)
689 return -errno;
690
691 return 0;
692 }
693
694 /*
695 * Checks whether a and b are identical or device
696 * files associated with the same block device
697 */
698 static int is_same_blk_file(const char* a, const char* b)
699 {
700 struct stat st_buf_a, st_buf_b;
701 char real_a[PATH_MAX];
702 char real_b[PATH_MAX];
703
704 if (!realpath(a, real_a))
705 strncpy_null(real_a, a);
706
707 if (!realpath(b, real_b))
708 strncpy_null(real_b, b);
709
710 /* Identical path? */
711 if (strcmp(real_a, real_b) == 0)
712 return 1;
713
714 if (stat(a, &st_buf_a) < 0 || stat(b, &st_buf_b) < 0) {
715 if (errno == ENOENT)
716 return 0;
717 return -errno;
718 }
719
720 /* Same blockdevice? */
721 if (S_ISBLK(st_buf_a.st_mode) && S_ISBLK(st_buf_b.st_mode) &&
722 st_buf_a.st_rdev == st_buf_b.st_rdev) {
723 return 1;
724 }
725
726 /* Hardlink? */
727 if (st_buf_a.st_dev == st_buf_b.st_dev &&
728 st_buf_a.st_ino == st_buf_b.st_ino) {
729 return 1;
730 }
731
732 return 0;
733 }
734
735 /* checks if a and b are identical or device
736 * files associated with the same block device or
737 * if one file is a loop device that uses the other
738 * file.
739 */
740 static int is_same_loop_file(const char* a, const char* b)
741 {
742 char res_a[PATH_MAX];
743 char res_b[PATH_MAX];
744 const char* final_a = NULL;
745 const char* final_b = NULL;
746 int ret;
747
748 /* Resolve a if it is a loop device */
749 if((ret = is_loop_device(a)) < 0) {
750 if (ret == -ENOENT)
751 return 0;
752 return ret;
753 } else if (ret) {
754 ret = resolve_loop_device(a, res_a, sizeof(res_a));
755 if (ret < 0) {
756 if (errno != EPERM)
757 return ret;
758 } else {
759 final_a = res_a;
760 }
761 } else {
762 final_a = a;
763 }
764
765 /* Resolve b if it is a loop device */
766 if ((ret = is_loop_device(b)) < 0) {
767 if (ret == -ENOENT)
768 return 0;
769 return ret;
770 } else if (ret) {
771 ret = resolve_loop_device(b, res_b, sizeof(res_b));
772 if (ret < 0) {
773 if (errno != EPERM)
774 return ret;
775 } else {
776 final_b = res_b;
777 }
778 } else {
779 final_b = b;
780 }
781
782 return is_same_blk_file(final_a, final_b);
783 }
784
785 /* Checks if a file exists and is a block or regular file*/
786 static int is_existing_blk_or_reg_file(const char* filename)
787 {
788 struct stat st_buf;
789
790 if(stat(filename, &st_buf) < 0) {
791 if(errno == ENOENT)
792 return 0;
793 else
794 return -errno;
795 }
796
797 return (S_ISBLK(st_buf.st_mode) || S_ISREG(st_buf.st_mode));
798 }
799
800 /* Checks if a file is used (directly or indirectly via a loop device)
801 * by a device in fs_devices
802 */
803 static int blk_file_in_dev_list(struct btrfs_fs_devices* fs_devices,
804 const char* file)
805 {
806 int ret;
807 struct list_head *head;
808 struct list_head *cur;
809 struct btrfs_device *device;
810
811 head = &fs_devices->devices;
812 list_for_each(cur, head) {
813 device = list_entry(cur, struct btrfs_device, dev_list);
814
815 if((ret = is_same_loop_file(device->name, file)))
816 return ret;
817 }
818
819 return 0;
820 }
821
822 /*
823 * Resolve a pathname to a device mapper node to /dev/mapper/<name>
824 * Returns NULL on invalid input or malloc failure; Other failures
825 * will be handled by the caller using the input pathame.
826 */
827 char *canonicalize_dm_name(const char *ptname)
828 {
829 FILE *f;
830 size_t sz;
831 char path[PATH_MAX], name[PATH_MAX], *res = NULL;
832
833 if (!ptname || !*ptname)
834 return NULL;
835
836 snprintf(path, sizeof(path), "/sys/block/%s/dm/name", ptname);
837 if (!(f = fopen(path, "r")))
838 return NULL;
839
840 /* read <name>\n from sysfs */
841 if (fgets(name, sizeof(name), f) && (sz = strlen(name)) > 1) {
842 name[sz - 1] = '\0';
843 snprintf(path, sizeof(path), "/dev/mapper/%s", name);
844
845 if (access(path, F_OK) == 0)
846 res = strdup(path);
847 }
848 fclose(f);
849 return res;
850 }
851
852 /*
853 * Resolve a pathname to a canonical device node, e.g. /dev/sda1 or
854 * to a device mapper pathname.
855 * Returns NULL on invalid input or malloc failure; Other failures
856 * will be handled by the caller using the input pathame.
857 */
858 char *canonicalize_path(const char *path)
859 {
860 char *canonical, *p;
861
862 if (!path || !*path)
863 return NULL;
864
865 canonical = realpath(path, NULL);
866 if (!canonical)
867 return strdup(path);
868 p = strrchr(canonical, '/');
869 if (p && strncmp(p, "/dm-", 4) == 0 && isdigit(*(p + 4))) {
870 char *dm = canonicalize_dm_name(p + 1);
871
872 if (dm) {
873 free(canonical);
874 return dm;
875 }
876 }
877 return canonical;
878 }
879
880 /*
881 * returns 1 if the device was mounted, < 0 on error or 0 if everything
882 * is safe to continue.
883 */
884 int check_mounted(const char* file)
885 {
886 int fd;
887 int ret;
888
889 fd = open(file, O_RDONLY);
890 if (fd < 0) {
891 error("mount check: cannot open %s: %s", file,
892 strerror(errno));
893 return -errno;
894 }
895
896 ret = check_mounted_where(fd, file, NULL, 0, NULL);
897 close(fd);
898
899 return ret;
900 }
901
902 int check_mounted_where(int fd, const char *file, char *where, int size,
903 struct btrfs_fs_devices **fs_dev_ret)
904 {
905 int ret;
906 u64 total_devs = 1;
907 int is_btrfs;
908 struct btrfs_fs_devices *fs_devices_mnt = NULL;
909 FILE *f;
910 struct mntent *mnt;
911
912 /* scan the initial device */
913 ret = btrfs_scan_one_device(fd, file, &fs_devices_mnt,
914 &total_devs, BTRFS_SUPER_INFO_OFFSET, SBREAD_DEFAULT);
915 is_btrfs = (ret >= 0);
916
917 /* scan other devices */
918 if (is_btrfs && total_devs > 1) {
919 ret = btrfs_scan_devices();
920 if (ret)
921 return ret;
922 }
923
924 /* iterate over the list of currently mounted filesystems */
925 if ((f = setmntent ("/proc/self/mounts", "r")) == NULL)
926 return -errno;
927
928 while ((mnt = getmntent (f)) != NULL) {
929 if(is_btrfs) {
930 if(strcmp(mnt->mnt_type, "btrfs") != 0)
931 continue;
932
933 ret = blk_file_in_dev_list(fs_devices_mnt, mnt->mnt_fsname);
934 } else {
935 /* ignore entries in the mount table that are not
936 associated with a file*/
937 if((ret = is_existing_blk_or_reg_file(mnt->mnt_fsname)) < 0)
938 goto out_mntloop_err;
939 else if(!ret)
940 continue;
941
942 ret = is_same_loop_file(file, mnt->mnt_fsname);
943 }
944
945 if(ret < 0)
946 goto out_mntloop_err;
947 else if(ret)
948 break;
949 }
950
951 /* Did we find an entry in mnt table? */
952 if (mnt && size && where) {
953 strncpy(where, mnt->mnt_dir, size);
954 where[size-1] = 0;
955 }
956 if (fs_dev_ret)
957 *fs_dev_ret = fs_devices_mnt;
958
959 ret = (mnt != NULL);
960
961 out_mntloop_err:
962 endmntent (f);
963
964 return ret;
965 }
966
967 struct pending_dir {
968 struct list_head list;
969 char name[PATH_MAX];
970 };
971
972 int btrfs_register_one_device(const char *fname)
973 {
974 struct btrfs_ioctl_vol_args args;
975 int fd;
976 int ret;
977
978 fd = open("/dev/btrfs-control", O_RDWR);
979 if (fd < 0) {
980 warning(
981 "failed to open /dev/btrfs-control, skipping device registration: %s",
982 strerror(errno));
983 return -errno;
984 }
985 memset(&args, 0, sizeof(args));
986 strncpy_null(args.name, fname);
987 ret = ioctl(fd, BTRFS_IOC_SCAN_DEV, &args);
988 if (ret < 0) {
989 error("device scan failed on '%s': %s", fname,
990 strerror(errno));
991 ret = -errno;
992 }
993 close(fd);
994 return ret;
995 }
996
997 /*
998 * Register all devices in the fs_uuid list created in the user
999 * space. Ensure btrfs_scan_devices() is called before this func.
1000 */
1001 int btrfs_register_all_devices(void)
1002 {
1003 int err = 0;
1004 int ret = 0;
1005 struct btrfs_fs_devices *fs_devices;
1006 struct btrfs_device *device;
1007 struct list_head *all_uuids;
1008
1009 all_uuids = btrfs_scanned_uuids();
1010
1011 list_for_each_entry(fs_devices, all_uuids, list) {
1012 list_for_each_entry(device, &fs_devices->devices, dev_list) {
1013 if (*device->name)
1014 err = btrfs_register_one_device(device->name);
1015
1016 if (err)
1017 ret++;
1018 }
1019 }
1020
1021 return ret;
1022 }
1023
1024 int btrfs_device_already_in_root(struct btrfs_root *root, int fd,
1025 int super_offset)
1026 {
1027 struct btrfs_super_block *disk_super;
1028 char *buf;
1029 int ret = 0;
1030
1031 buf = malloc(BTRFS_SUPER_INFO_SIZE);
1032 if (!buf) {
1033 ret = -ENOMEM;
1034 goto out;
1035 }
1036 ret = pread(fd, buf, BTRFS_SUPER_INFO_SIZE, super_offset);
1037 if (ret != BTRFS_SUPER_INFO_SIZE)
1038 goto brelse;
1039
1040 ret = 0;
1041 disk_super = (struct btrfs_super_block *)buf;
1042 /*
1043 * Accept devices from the same filesystem, allow partially created
1044 * structures.
1045 */
1046 if (btrfs_super_magic(disk_super) != BTRFS_MAGIC &&
1047 btrfs_super_magic(disk_super) != BTRFS_MAGIC_PARTIAL)
1048 goto brelse;
1049
1050 if (!memcmp(disk_super->fsid, root->fs_info->super_copy->fsid,
1051 BTRFS_FSID_SIZE))
1052 ret = 1;
1053 brelse:
1054 free(buf);
1055 out:
1056 return ret;
1057 }
1058
1059 /*
1060 * Note: this function uses a static per-thread buffer. Do not call this
1061 * function more than 10 times within one argument list!
1062 */
1063 const char *pretty_size_mode(u64 size, unsigned mode)
1064 {
1065 static __thread int ps_index = 0;
1066 static __thread char ps_array[10][32];
1067 char *ret;
1068
1069 ret = ps_array[ps_index];
1070 ps_index++;
1071 ps_index %= 10;
1072 (void)pretty_size_snprintf(size, ret, 32, mode);
1073
1074 return ret;
1075 }
1076
1077 static const char* unit_suffix_binary[] =
1078 { "B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"};
1079 static const char* unit_suffix_decimal[] =
1080 { "B", "kB", "MB", "GB", "TB", "PB", "EB"};
1081
1082 int pretty_size_snprintf(u64 size, char *str, size_t str_size, unsigned unit_mode)
1083 {
1084 int num_divs;
1085 float fraction;
1086 u64 base = 0;
1087 int mult = 0;
1088 const char** suffix = NULL;
1089 u64 last_size;
1090 int negative;
1091
1092 if (str_size == 0)
1093 return 0;
1094
1095 negative = !!(unit_mode & UNITS_NEGATIVE);
1096 unit_mode &= ~UNITS_NEGATIVE;
1097
1098 if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_RAW) {
1099 if (negative)
1100 snprintf(str, str_size, "%lld", size);
1101 else
1102 snprintf(str, str_size, "%llu", size);
1103 return 0;
1104 }
1105
1106 if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_BINARY) {
1107 base = 1024;
1108 mult = 1024;
1109 suffix = unit_suffix_binary;
1110 } else if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_DECIMAL) {
1111 base = 1000;
1112 mult = 1000;
1113 suffix = unit_suffix_decimal;
1114 }
1115
1116 /* Unknown mode */
1117 if (!base) {
1118 fprintf(stderr, "INTERNAL ERROR: unknown unit base, mode %d\n",
1119 unit_mode);
1120 assert(0);
1121 return -1;
1122 }
1123
1124 num_divs = 0;
1125 last_size = size;
1126 switch (unit_mode & UNITS_MODE_MASK) {
1127 case UNITS_TBYTES: base *= mult; num_divs++;
1128 case UNITS_GBYTES: base *= mult; num_divs++;
1129 case UNITS_MBYTES: base *= mult; num_divs++;
1130 case UNITS_KBYTES: num_divs++;
1131 break;
1132 case UNITS_BYTES:
1133 base = 1;
1134 num_divs = 0;
1135 break;
1136 default:
1137 if (negative) {
1138 s64 ssize = (s64)size;
1139 s64 last_ssize = ssize;
1140
1141 while ((ssize < 0 ? -ssize : ssize) >= mult) {
1142 last_ssize = ssize;
1143 ssize /= mult;
1144 num_divs++;
1145 }
1146 last_size = (u64)last_ssize;
1147 } else {
1148 while (size >= mult) {
1149 last_size = size;
1150 size /= mult;
1151 num_divs++;
1152 }
1153 }
1154 /*
1155 * If the value is smaller than base, we didn't do any
1156 * division, in that case, base should be 1, not original
1157 * base, or the unit will be wrong
1158 */
1159 if (num_divs == 0)
1160 base = 1;
1161 }
1162
1163 if (num_divs >= ARRAY_SIZE(unit_suffix_binary)) {
1164 str[0] = '\0';
1165 printf("INTERNAL ERROR: unsupported unit suffix, index %d\n",
1166 num_divs);
1167 assert(0);
1168 return -1;
1169 }
1170
1171 if (negative) {
1172 fraction = (float)(s64)last_size / base;
1173 } else {
1174 fraction = (float)last_size / base;
1175 }
1176
1177 return snprintf(str, str_size, "%.2f%s", fraction, suffix[num_divs]);
1178 }
1179
1180 /*
1181 * __strncpy_null - strncpy with null termination
1182 * @dest: the target array
1183 * @src: the source string
1184 * @n: maximum bytes to copy (size of *dest)
1185 *
1186 * Like strncpy, but ensures destination is null-terminated.
1187 *
1188 * Copies the string pointed to by src, including the terminating null
1189 * byte ('\0'), to the buffer pointed to by dest, up to a maximum
1190 * of n bytes. Then ensure that dest is null-terminated.
1191 */
1192 char *__strncpy_null(char *dest, const char *src, size_t n)
1193 {
1194 strncpy(dest, src, n);
1195 if (n > 0)
1196 dest[n - 1] = '\0';
1197 return dest;
1198 }
1199
1200 /*
1201 * Checks to make sure that the label matches our requirements.
1202 * Returns:
1203 0 if everything is safe and usable
1204 -1 if the label is too long
1205 */
1206 static int check_label(const char *input)
1207 {
1208 int len = strlen(input);
1209
1210 if (len > BTRFS_LABEL_SIZE - 1) {
1211 error("label %s is too long (max %d)", input,
1212 BTRFS_LABEL_SIZE - 1);
1213 return -1;
1214 }
1215
1216 return 0;
1217 }
1218
1219 static int set_label_unmounted(const char *dev, const char *label)
1220 {
1221 struct btrfs_trans_handle *trans;
1222 struct btrfs_root *root;
1223 int ret;
1224
1225 ret = check_mounted(dev);
1226 if (ret < 0) {
1227 error("checking mount status of %s failed: %d", dev, ret);
1228 return -1;
1229 }
1230 if (ret > 0) {
1231 error("device %s is mounted, use mount point", dev);
1232 return -1;
1233 }
1234
1235 /* Open the super_block at the default location
1236 * and as read-write.
1237 */
1238 root = open_ctree(dev, 0, OPEN_CTREE_WRITES);
1239 if (!root) /* errors are printed by open_ctree() */
1240 return -1;
1241
1242 trans = btrfs_start_transaction(root, 1);
1243 BUG_ON(IS_ERR(trans));
1244 __strncpy_null(root->fs_info->super_copy->label, label, BTRFS_LABEL_SIZE - 1);
1245
1246 btrfs_commit_transaction(trans, root);
1247
1248 /* Now we close it since we are done. */
1249 close_ctree(root);
1250 return 0;
1251 }
1252
1253 static int set_label_mounted(const char *mount_path, const char *labelp)
1254 {
1255 int fd;
1256 char label[BTRFS_LABEL_SIZE];
1257
1258 fd = open(mount_path, O_RDONLY | O_NOATIME);
1259 if (fd < 0) {
1260 error("unable to access %s: %s", mount_path, strerror(errno));
1261 return -1;
1262 }
1263
1264 memset(label, 0, sizeof(label));
1265 __strncpy_null(label, labelp, BTRFS_LABEL_SIZE - 1);
1266 if (ioctl(fd, BTRFS_IOC_SET_FSLABEL, label) < 0) {
1267 error("unable to set label of %s: %s", mount_path,
1268 strerror(errno));
1269 close(fd);
1270 return -1;
1271 }
1272
1273 close(fd);
1274 return 0;
1275 }
1276
1277 int get_label_unmounted(const char *dev, char *label)
1278 {
1279 struct btrfs_root *root;
1280 int ret;
1281
1282 ret = check_mounted(dev);
1283 if (ret < 0) {
1284 error("checking mount status of %s failed: %d", dev, ret);
1285 return -1;
1286 }
1287
1288 /* Open the super_block at the default location
1289 * and as read-only.
1290 */
1291 root = open_ctree(dev, 0, 0);
1292 if(!root)
1293 return -1;
1294
1295 __strncpy_null(label, root->fs_info->super_copy->label,
1296 BTRFS_LABEL_SIZE - 1);
1297
1298 /* Now we close it since we are done. */
1299 close_ctree(root);
1300 return 0;
1301 }
1302
1303 /*
1304 * If a partition is mounted, try to get the filesystem label via its
1305 * mounted path rather than device. Return the corresponding error
1306 * the user specified the device path.
1307 */
1308 int get_label_mounted(const char *mount_path, char *labelp)
1309 {
1310 char label[BTRFS_LABEL_SIZE];
1311 int fd;
1312 int ret;
1313
1314 fd = open(mount_path, O_RDONLY | O_NOATIME);
1315 if (fd < 0) {
1316 error("unable to access %s: %s", mount_path, strerror(errno));
1317 return -1;
1318 }
1319
1320 memset(label, '\0', sizeof(label));
1321 ret = ioctl(fd, BTRFS_IOC_GET_FSLABEL, label);
1322 if (ret < 0) {
1323 if (errno != ENOTTY)
1324 error("unable to get label of %s: %s", mount_path,
1325 strerror(errno));
1326 ret = -errno;
1327 close(fd);
1328 return ret;
1329 }
1330
1331 __strncpy_null(labelp, label, BTRFS_LABEL_SIZE - 1);
1332 close(fd);
1333 return 0;
1334 }
1335
1336 int get_label(const char *btrfs_dev, char *label)
1337 {
1338 int ret;
1339
1340 ret = is_existing_blk_or_reg_file(btrfs_dev);
1341 if (!ret)
1342 ret = get_label_mounted(btrfs_dev, label);
1343 else if (ret > 0)
1344 ret = get_label_unmounted(btrfs_dev, label);
1345
1346 return ret;
1347 }
1348
1349 int set_label(const char *btrfs_dev, const char *label)
1350 {
1351 int ret;
1352
1353 if (check_label(label))
1354 return -1;
1355
1356 ret = is_existing_blk_or_reg_file(btrfs_dev);
1357 if (!ret)
1358 ret = set_label_mounted(btrfs_dev, label);
1359 else if (ret > 0)
1360 ret = set_label_unmounted(btrfs_dev, label);
1361
1362 return ret;
1363 }
1364
1365 /*
1366 * A not-so-good version fls64. No fascinating optimization since
1367 * no one except parse_size use it
1368 */
1369 static int fls64(u64 x)
1370 {
1371 int i;
1372
1373 for (i = 0; i <64; i++)
1374 if (x << i & (1ULL << 63))
1375 return 64 - i;
1376 return 64 - i;
1377 }
1378
1379 u64 parse_size(char *s)
1380 {
1381 char c;
1382 char *endptr;
1383 u64 mult = 1;
1384 u64 ret;
1385
1386 if (!s) {
1387 error("size value is empty");
1388 exit(1);
1389 }
1390 if (s[0] == '-') {
1391 error("size value '%s' is less equal than 0", s);
1392 exit(1);
1393 }
1394 ret = strtoull(s, &endptr, 10);
1395 if (endptr == s) {
1396 error("size value '%s' is invalid", s);
1397 exit(1);
1398 }
1399 if (endptr[0] && endptr[1]) {
1400 error("illegal suffix contains character '%c' in wrong position",
1401 endptr[1]);
1402 exit(1);
1403 }
1404 /*
1405 * strtoll returns LLONG_MAX when overflow, if this happens,
1406 * need to call strtoull to get the real size
1407 */
1408 if (errno == ERANGE && ret == ULLONG_MAX) {
1409 error("size value '%s' is too large for u64", s);
1410 exit(1);
1411 }
1412 if (endptr[0]) {
1413 c = tolower(endptr[0]);
1414 switch (c) {
1415 case 'e':
1416 mult *= 1024;
1417 /* fallthrough */
1418 case 'p':
1419 mult *= 1024;
1420 /* fallthrough */
1421 case 't':
1422 mult *= 1024;
1423 /* fallthrough */
1424 case 'g':
1425 mult *= 1024;
1426 /* fallthrough */
1427 case 'm':
1428 mult *= 1024;
1429 /* fallthrough */
1430 case 'k':
1431 mult *= 1024;
1432 /* fallthrough */
1433 case 'b':
1434 break;
1435 default:
1436 error("unknown size descriptor '%c'", c);
1437 exit(1);
1438 }
1439 }
1440 /* Check whether ret * mult overflow */
1441 if (fls64(ret) + fls64(mult) - 1 > 64) {
1442 error("size value '%s' is too large for u64", s);
1443 exit(1);
1444 }
1445 ret *= mult;
1446 return ret;
1447 }
1448
1449 u64 parse_qgroupid(const char *p)
1450 {
1451 char *s = strchr(p, '/');
1452 const char *ptr_src_end = p + strlen(p);
1453 char *ptr_parse_end = NULL;
1454 u64 level;
1455 u64 id;
1456 int fd;
1457 int ret = 0;
1458
1459 if (p[0] == '/')
1460 goto path;
1461
1462 /* Numeric format like '0/257' is the primary case */
1463 if (!s) {
1464 id = strtoull(p, &ptr_parse_end, 10);
1465 if (ptr_parse_end != ptr_src_end)
1466 goto path;
1467 return id;
1468 }
1469 level = strtoull(p, &ptr_parse_end, 10);
1470 if (ptr_parse_end != s)
1471 goto path;
1472
1473 id = strtoull(s + 1, &ptr_parse_end, 10);
1474 if (ptr_parse_end != ptr_src_end)
1475 goto path;
1476
1477 return (level << BTRFS_QGROUP_LEVEL_SHIFT) | id;
1478
1479 path:
1480 /* Path format like subv at 'my_subvol' is the fallback case */
1481 ret = test_issubvolume(p);
1482 if (ret < 0 || !ret)
1483 goto err;
1484 fd = open(p, O_RDONLY);
1485 if (fd < 0)
1486 goto err;
1487 ret = lookup_path_rootid(fd, &id);
1488 if (ret)
1489 error("failed to lookup root id: %s", strerror(-ret));
1490 close(fd);
1491 if (ret < 0)
1492 goto err;
1493 return id;
1494
1495 err:
1496 error("invalid qgroupid or subvolume path: %s", p);
1497 exit(-1);
1498 }
1499
1500 int open_file_or_dir3(const char *fname, DIR **dirstream, int open_flags)
1501 {
1502 int ret;
1503 struct stat st;
1504 int fd;
1505
1506 ret = stat(fname, &st);
1507 if (ret < 0) {
1508 return -1;
1509 }
1510 if (S_ISDIR(st.st_mode)) {
1511 *dirstream = opendir(fname);
1512 if (!*dirstream)
1513 return -1;
1514 fd = dirfd(*dirstream);
1515 } else if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)) {
1516 fd = open(fname, open_flags);
1517 } else {
1518 /*
1519 * we set this on purpose, in case the caller output
1520 * strerror(errno) as success
1521 */
1522 errno = EINVAL;
1523 return -1;
1524 }
1525 if (fd < 0) {
1526 fd = -1;
1527 if (*dirstream) {
1528 closedir(*dirstream);
1529 *dirstream = NULL;
1530 }
1531 }
1532 return fd;
1533 }
1534
1535 int open_file_or_dir(const char *fname, DIR **dirstream)
1536 {
1537 return open_file_or_dir3(fname, dirstream, O_RDWR);
1538 }
1539
1540 void close_file_or_dir(int fd, DIR *dirstream)
1541 {
1542 if (dirstream)
1543 closedir(dirstream);
1544 else if (fd >= 0)
1545 close(fd);
1546 }
1547
1548 int get_device_info(int fd, u64 devid,
1549 struct btrfs_ioctl_dev_info_args *di_args)
1550 {
1551 int ret;
1552
1553 di_args->devid = devid;
1554 memset(&di_args->uuid, '\0', sizeof(di_args->uuid));
1555
1556 ret = ioctl(fd, BTRFS_IOC_DEV_INFO, di_args);
1557 return ret < 0 ? -errno : 0;
1558 }
1559
1560 static u64 find_max_device_id(struct btrfs_ioctl_search_args *search_args,
1561 int nr_items)
1562 {
1563 struct btrfs_dev_item *dev_item;
1564 char *buf = search_args->buf;
1565
1566 buf += (nr_items - 1) * (sizeof(struct btrfs_ioctl_search_header)
1567 + sizeof(struct btrfs_dev_item));
1568 buf += sizeof(struct btrfs_ioctl_search_header);
1569
1570 dev_item = (struct btrfs_dev_item *)buf;
1571
1572 return btrfs_stack_device_id(dev_item);
1573 }
1574
1575 static int search_chunk_tree_for_fs_info(int fd,
1576 struct btrfs_ioctl_fs_info_args *fi_args)
1577 {
1578 int ret;
1579 int max_items;
1580 u64 start_devid = 1;
1581 struct btrfs_ioctl_search_args search_args;
1582 struct btrfs_ioctl_search_key *search_key = &search_args.key;
1583
1584 fi_args->num_devices = 0;
1585
1586 max_items = BTRFS_SEARCH_ARGS_BUFSIZE
1587 / (sizeof(struct btrfs_ioctl_search_header)
1588 + sizeof(struct btrfs_dev_item));
1589
1590 search_key->tree_id = BTRFS_CHUNK_TREE_OBJECTID;
1591 search_key->min_objectid = BTRFS_DEV_ITEMS_OBJECTID;
1592 search_key->max_objectid = BTRFS_DEV_ITEMS_OBJECTID;
1593 search_key->min_type = BTRFS_DEV_ITEM_KEY;
1594 search_key->max_type = BTRFS_DEV_ITEM_KEY;
1595 search_key->min_transid = 0;
1596 search_key->max_transid = (u64)-1;
1597 search_key->nr_items = max_items;
1598 search_key->max_offset = (u64)-1;
1599
1600 again:
1601 search_key->min_offset = start_devid;
1602
1603 ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &search_args);
1604 if (ret < 0)
1605 return -errno;
1606
1607 fi_args->num_devices += (u64)search_key->nr_items;
1608
1609 if (search_key->nr_items == max_items) {
1610 start_devid = find_max_device_id(&search_args,
1611 search_key->nr_items) + 1;
1612 goto again;
1613 }
1614
1615 /* get the lastest max_id to stay consistent with the num_devices */
1616 if (search_key->nr_items == 0)
1617 /*
1618 * last tree_search returns an empty buf, use the devid of
1619 * the last dev_item of the previous tree_search
1620 */
1621 fi_args->max_id = start_devid - 1;
1622 else
1623 fi_args->max_id = find_max_device_id(&search_args,
1624 search_key->nr_items);
1625
1626 return 0;
1627 }
1628
1629 /*
1630 * For a given path, fill in the ioctl fs_ and info_ args.
1631 * If the path is a btrfs mountpoint, fill info for all devices.
1632 * If the path is a btrfs device, fill in only that device.
1633 *
1634 * The path provided must be either on a mounted btrfs fs,
1635 * or be a mounted btrfs device.
1636 *
1637 * Returns 0 on success, or a negative errno.
1638 */
1639 int get_fs_info(const char *path, struct btrfs_ioctl_fs_info_args *fi_args,
1640 struct btrfs_ioctl_dev_info_args **di_ret)
1641 {
1642 int fd = -1;
1643 int ret = 0;
1644 int ndevs = 0;
1645 u64 last_devid = 0;
1646 int replacing = 0;
1647 struct btrfs_fs_devices *fs_devices_mnt = NULL;
1648 struct btrfs_ioctl_dev_info_args *di_args;
1649 struct btrfs_ioctl_dev_info_args tmp;
1650 char mp[PATH_MAX];
1651 DIR *dirstream = NULL;
1652
1653 memset(fi_args, 0, sizeof(*fi_args));
1654
1655 if (is_block_device(path) == 1) {
1656 struct btrfs_super_block *disk_super;
1657 char buf[BTRFS_SUPER_INFO_SIZE];
1658
1659 /* Ensure it's mounted, then set path to the mountpoint */
1660 fd = open(path, O_RDONLY);
1661 if (fd < 0) {
1662 ret = -errno;
1663 error("cannot open %s: %s", path, strerror(errno));
1664 goto out;
1665 }
1666 ret = check_mounted_where(fd, path, mp, sizeof(mp),
1667 &fs_devices_mnt);
1668 if (!ret) {
1669 ret = -EINVAL;
1670 goto out;
1671 }
1672 if (ret < 0)
1673 goto out;
1674 path = mp;
1675 /* Only fill in this one device */
1676 fi_args->num_devices = 1;
1677
1678 disk_super = (struct btrfs_super_block *)buf;
1679 ret = btrfs_read_dev_super(fd, disk_super,
1680 BTRFS_SUPER_INFO_OFFSET, 0);
1681 if (ret < 0) {
1682 ret = -EIO;
1683 goto out;
1684 }
1685 last_devid = btrfs_stack_device_id(&disk_super->dev_item);
1686 fi_args->max_id = last_devid;
1687
1688 memcpy(fi_args->fsid, fs_devices_mnt->fsid, BTRFS_FSID_SIZE);
1689 close(fd);
1690 }
1691
1692 /* at this point path must not be for a block device */
1693 fd = open_file_or_dir(path, &dirstream);
1694 if (fd < 0) {
1695 ret = -errno;
1696 goto out;
1697 }
1698
1699 /* fill in fi_args if not just a single device */
1700 if (fi_args->num_devices != 1) {
1701 ret = ioctl(fd, BTRFS_IOC_FS_INFO, fi_args);
1702 if (ret < 0) {
1703 ret = -errno;
1704 goto out;
1705 }
1706
1707 /*
1708 * The fs_args->num_devices does not include seed devices
1709 */
1710 ret = search_chunk_tree_for_fs_info(fd, fi_args);
1711 if (ret)
1712 goto out;
1713
1714 /*
1715 * search_chunk_tree_for_fs_info() will lacks the devid 0
1716 * so manual probe for it here.
1717 */
1718 ret = get_device_info(fd, 0, &tmp);
1719 if (!ret) {
1720 fi_args->num_devices++;
1721 ndevs++;
1722 replacing = 1;
1723 if (last_devid == 0)
1724 last_devid++;
1725 }
1726 }
1727
1728 if (!fi_args->num_devices)
1729 goto out;
1730
1731 di_args = *di_ret = malloc((fi_args->num_devices) * sizeof(*di_args));
1732 if (!di_args) {
1733 ret = -errno;
1734 goto out;
1735 }
1736
1737 if (replacing)
1738 memcpy(di_args, &tmp, sizeof(tmp));
1739 for (; last_devid <= fi_args->max_id; last_devid++) {
1740 ret = get_device_info(fd, last_devid, &di_args[ndevs]);
1741 if (ret == -ENODEV)
1742 continue;
1743 if (ret)
1744 goto out;
1745 ndevs++;
1746 }
1747
1748 /*
1749 * only when the only dev we wanted to find is not there then
1750 * let any error be returned
1751 */
1752 if (fi_args->num_devices != 1) {
1753 BUG_ON(ndevs == 0);
1754 ret = 0;
1755 }
1756
1757 out:
1758 close_file_or_dir(fd, dirstream);
1759 return ret;
1760 }
1761
1762 int get_fsid(const char *path, u8 *fsid, int silent)
1763 {
1764 int ret;
1765 int fd;
1766 struct btrfs_ioctl_fs_info_args args;
1767
1768 fd = open(path, O_RDONLY);
1769 if (fd < 0) {
1770 ret = -errno;
1771 if (!silent)
1772 error("failed to open %s: %s", path,
1773 strerror(-ret));
1774 goto out;
1775 }
1776
1777 ret = ioctl(fd, BTRFS_IOC_FS_INFO, &args);
1778 if (ret < 0) {
1779 ret = -errno;
1780 goto out;
1781 }
1782
1783 memcpy(fsid, args.fsid, BTRFS_FSID_SIZE);
1784 ret = 0;
1785
1786 out:
1787 if (fd != -1)
1788 close(fd);
1789 return ret;
1790 }
1791
1792 int is_seen_fsid(u8 *fsid, struct seen_fsid *seen_fsid_hash[])
1793 {
1794 u8 hash = fsid[0];
1795 int slot = hash % SEEN_FSID_HASH_SIZE;
1796 struct seen_fsid *seen = seen_fsid_hash[slot];
1797
1798 while (seen) {
1799 if (memcmp(seen->fsid, fsid, BTRFS_FSID_SIZE) == 0)
1800 return 1;
1801
1802 seen = seen->next;
1803 }
1804
1805 return 0;
1806 }
1807
1808 int add_seen_fsid(u8 *fsid, struct seen_fsid *seen_fsid_hash[],
1809 int fd, DIR *dirstream)
1810 {
1811 u8 hash = fsid[0];
1812 int slot = hash % SEEN_FSID_HASH_SIZE;
1813 struct seen_fsid *seen = seen_fsid_hash[slot];
1814 struct seen_fsid *alloc;
1815
1816 if (!seen)
1817 goto insert;
1818
1819 while (1) {
1820 if (memcmp(seen->fsid, fsid, BTRFS_FSID_SIZE) == 0)
1821 return -EEXIST;
1822
1823 if (!seen->next)
1824 break;
1825
1826 seen = seen->next;
1827 }
1828
1829 insert:
1830 alloc = malloc(sizeof(*alloc));
1831 if (!alloc)
1832 return -ENOMEM;
1833
1834 alloc->next = NULL;
1835 memcpy(alloc->fsid, fsid, BTRFS_FSID_SIZE);
1836 alloc->fd = fd;
1837 alloc->dirstream = dirstream;
1838
1839 if (seen)
1840 seen->next = alloc;
1841 else
1842 seen_fsid_hash[slot] = alloc;
1843
1844 return 0;
1845 }
1846
1847 void free_seen_fsid(struct seen_fsid *seen_fsid_hash[])
1848 {
1849 int slot;
1850 struct seen_fsid *seen;
1851 struct seen_fsid *next;
1852
1853 for (slot = 0; slot < SEEN_FSID_HASH_SIZE; slot++) {
1854 seen = seen_fsid_hash[slot];
1855 while (seen) {
1856 next = seen->next;
1857 close_file_or_dir(seen->fd, seen->dirstream);
1858 free(seen);
1859 seen = next;
1860 }
1861 seen_fsid_hash[slot] = NULL;
1862 }
1863 }
1864
1865 static int group_profile_devs_min(u64 flag)
1866 {
1867 switch (flag & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
1868 case 0: /* single */
1869 case BTRFS_BLOCK_GROUP_DUP:
1870 return 1;
1871 case BTRFS_BLOCK_GROUP_RAID0:
1872 case BTRFS_BLOCK_GROUP_RAID1:
1873 case BTRFS_BLOCK_GROUP_RAID5:
1874 return 2;
1875 case BTRFS_BLOCK_GROUP_RAID6:
1876 return 3;
1877 case BTRFS_BLOCK_GROUP_RAID10:
1878 return 4;
1879 default:
1880 return -1;
1881 }
1882 }
1883
1884 int test_num_disk_vs_raid(u64 metadata_profile, u64 data_profile,
1885 u64 dev_cnt, int mixed, int ssd)
1886 {
1887 u64 allowed = 0;
1888 u64 profile = metadata_profile | data_profile;
1889
1890 switch (dev_cnt) {
1891 default:
1892 case 4:
1893 allowed |= BTRFS_BLOCK_GROUP_RAID10;
1894 case 3:
1895 allowed |= BTRFS_BLOCK_GROUP_RAID6;
1896 case 2:
1897 allowed |= BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
1898 BTRFS_BLOCK_GROUP_RAID5;
1899 case 1:
1900 allowed |= BTRFS_BLOCK_GROUP_DUP;
1901 }
1902
1903 if (dev_cnt > 1 && profile & BTRFS_BLOCK_GROUP_DUP) {
1904 warning("DUP is not recommended on filesystem with multiple devices");
1905 }
1906 if (metadata_profile & ~allowed) {
1907 fprintf(stderr,
1908 "ERROR: unable to create FS with metadata profile %s "
1909 "(have %llu devices but %d devices are required)\n",
1910 btrfs_group_profile_str(metadata_profile), dev_cnt,
1911 group_profile_devs_min(metadata_profile));
1912 return 1;
1913 }
1914 if (data_profile & ~allowed) {
1915 fprintf(stderr,
1916 "ERROR: unable to create FS with data profile %s "
1917 "(have %llu devices but %d devices are required)\n",
1918 btrfs_group_profile_str(data_profile), dev_cnt,
1919 group_profile_devs_min(data_profile));
1920 return 1;
1921 }
1922
1923 if (dev_cnt == 3 && profile & BTRFS_BLOCK_GROUP_RAID6) {
1924 warning("RAID6 is not recommended on filesystem with 3 devices only");
1925 }
1926 if (dev_cnt == 2 && profile & BTRFS_BLOCK_GROUP_RAID5) {
1927 warning("RAID5 is not recommended on filesystem with 2 devices only");
1928 }
1929 warning_on(!mixed && (data_profile & BTRFS_BLOCK_GROUP_DUP) && ssd,
1930 "DUP may not actually lead to 2 copies on the device, see manual page");
1931
1932 return 0;
1933 }
1934
1935 int group_profile_max_safe_loss(u64 flags)
1936 {
1937 switch (flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
1938 case 0: /* single */
1939 case BTRFS_BLOCK_GROUP_DUP:
1940 case BTRFS_BLOCK_GROUP_RAID0:
1941 return 0;
1942 case BTRFS_BLOCK_GROUP_RAID1:
1943 case BTRFS_BLOCK_GROUP_RAID5:
1944 case BTRFS_BLOCK_GROUP_RAID10:
1945 return 1;
1946 case BTRFS_BLOCK_GROUP_RAID6:
1947 return 2;
1948 default:
1949 return -1;
1950 }
1951 }
1952
1953 int btrfs_scan_devices(void)
1954 {
1955 int fd = -1;
1956 int ret;
1957 u64 num_devices;
1958 struct btrfs_fs_devices *tmp_devices;
1959 blkid_dev_iterate iter = NULL;
1960 blkid_dev dev = NULL;
1961 blkid_cache cache = NULL;
1962 char path[PATH_MAX];
1963
1964 if (btrfs_scan_done)
1965 return 0;
1966
1967 if (blkid_get_cache(&cache, NULL) < 0) {
1968 error("blkid cache get failed");
1969 return 1;
1970 }
1971 blkid_probe_all(cache);
1972 iter = blkid_dev_iterate_begin(cache);
1973 blkid_dev_set_search(iter, "TYPE", "btrfs");
1974 while (blkid_dev_next(iter, &dev) == 0) {
1975 dev = blkid_verify(cache, dev);
1976 if (!dev)
1977 continue;
1978 /* if we are here its definitely a btrfs disk*/
1979 strncpy_null(path, blkid_dev_devname(dev));
1980
1981 fd = open(path, O_RDONLY);
1982 if (fd < 0) {
1983 error("cannot open %s: %s", path, strerror(errno));
1984 continue;
1985 }
1986 ret = btrfs_scan_one_device(fd, path, &tmp_devices,
1987 &num_devices, BTRFS_SUPER_INFO_OFFSET,
1988 SBREAD_DEFAULT);
1989 if (ret) {
1990 error("cannot scan %s: %s", path, strerror(-ret));
1991 close (fd);
1992 continue;
1993 }
1994
1995 close(fd);
1996 }
1997 blkid_dev_iterate_end(iter);
1998 blkid_put_cache(cache);
1999
2000 btrfs_scan_done = 1;
2001
2002 return 0;
2003 }
2004
2005 /*
2006 * This reads a line from the stdin and only returns non-zero if the
2007 * first whitespace delimited token is a case insensitive match with yes
2008 * or y.
2009 */
2010 int ask_user(const char *question)
2011 {
2012 char buf[30] = {0,};
2013 char *saveptr = NULL;
2014 char *answer;
2015
2016 printf("%s [y/N]: ", question);
2017
2018 return fgets(buf, sizeof(buf) - 1, stdin) &&
2019 (answer = strtok_r(buf, " \t\n\r", &saveptr)) &&
2020 (!strcasecmp(answer, "yes") || !strcasecmp(answer, "y"));
2021 }
2022
2023 /*
2024 * return 0 if a btrfs mount point is found
2025 * return 1 if a mount point is found but not btrfs
2026 * return <0 if something goes wrong
2027 */
2028 int find_mount_root(const char *path, char **mount_root)
2029 {
2030 FILE *mnttab;
2031 int fd;
2032 struct mntent *ent;
2033 int len;
2034 int ret;
2035 int not_btrfs = 1;
2036 int longest_matchlen = 0;
2037 char *longest_match = NULL;
2038
2039 fd = open(path, O_RDONLY | O_NOATIME);
2040 if (fd < 0)
2041 return -errno;
2042 close(fd);
2043
2044 mnttab = setmntent("/proc/self/mounts", "r");
2045 if (!mnttab)
2046 return -errno;
2047
2048 while ((ent = getmntent(mnttab))) {
2049 len = strlen(ent->mnt_dir);
2050 if (strncmp(ent->mnt_dir, path, len) == 0) {
2051 /* match found and use the latest match */
2052 if (longest_matchlen <= len) {
2053 free(longest_match);
2054 longest_matchlen = len;
2055 longest_match = strdup(ent->mnt_dir);
2056 not_btrfs = strcmp(ent->mnt_type, "btrfs");
2057 }
2058 }
2059 }
2060 endmntent(mnttab);
2061
2062 if (!longest_match)
2063 return -ENOENT;
2064 if (not_btrfs) {
2065 free(longest_match);
2066 return 1;
2067 }
2068
2069 ret = 0;
2070 *mount_root = realpath(longest_match, NULL);
2071 if (!*mount_root)
2072 ret = -errno;
2073
2074 free(longest_match);
2075 return ret;
2076 }
2077
2078 /*
2079 * Test if path is a directory
2080 * Returns:
2081 * 0 - path exists but it is not a directory
2082 * 1 - path exists and it is a directory
2083 * < 0 - error
2084 */
2085 int test_isdir(const char *path)
2086 {
2087 struct stat st;
2088 int ret;
2089
2090 ret = stat(path, &st);
2091 if (ret < 0)
2092 return -errno;
2093
2094 return !!S_ISDIR(st.st_mode);
2095 }
2096
2097 void units_set_mode(unsigned *units, unsigned mode)
2098 {
2099 unsigned base = *units & UNITS_MODE_MASK;
2100
2101 *units = base | mode;
2102 }
2103
2104 void units_set_base(unsigned *units, unsigned base)
2105 {
2106 unsigned mode = *units & ~UNITS_MODE_MASK;
2107
2108 *units = base | mode;
2109 }
2110
2111 int find_next_key(struct btrfs_path *path, struct btrfs_key *key)
2112 {
2113 int level;
2114
2115 for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
2116 if (!path->nodes[level])
2117 break;
2118 if (path->slots[level] + 1 >=
2119 btrfs_header_nritems(path->nodes[level]))
2120 continue;
2121 if (level == 0)
2122 btrfs_item_key_to_cpu(path->nodes[level], key,
2123 path->slots[level] + 1);
2124 else
2125 btrfs_node_key_to_cpu(path->nodes[level], key,
2126 path->slots[level] + 1);
2127 return 0;
2128 }
2129 return 1;
2130 }
2131
2132 const char* btrfs_group_type_str(u64 flag)
2133 {
2134 u64 mask = BTRFS_BLOCK_GROUP_TYPE_MASK |
2135 BTRFS_SPACE_INFO_GLOBAL_RSV;
2136
2137 switch (flag & mask) {
2138 case BTRFS_BLOCK_GROUP_DATA:
2139 return "Data";
2140 case BTRFS_BLOCK_GROUP_SYSTEM:
2141 return "System";
2142 case BTRFS_BLOCK_GROUP_METADATA:
2143 return "Metadata";
2144 case BTRFS_BLOCK_GROUP_DATA|BTRFS_BLOCK_GROUP_METADATA:
2145 return "Data+Metadata";
2146 case BTRFS_SPACE_INFO_GLOBAL_RSV:
2147 return "GlobalReserve";
2148 default:
2149 return "unknown";
2150 }
2151 }
2152
2153 const char* btrfs_group_profile_str(u64 flag)
2154 {
2155 switch (flag & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
2156 case 0:
2157 return "single";
2158 case BTRFS_BLOCK_GROUP_RAID0:
2159 return "RAID0";
2160 case BTRFS_BLOCK_GROUP_RAID1:
2161 return "RAID1";
2162 case BTRFS_BLOCK_GROUP_RAID5:
2163 return "RAID5";
2164 case BTRFS_BLOCK_GROUP_RAID6:
2165 return "RAID6";
2166 case BTRFS_BLOCK_GROUP_DUP:
2167 return "DUP";
2168 case BTRFS_BLOCK_GROUP_RAID10:
2169 return "RAID10";
2170 default:
2171 return "unknown";
2172 }
2173 }
2174
2175 u64 disk_size(const char *path)
2176 {
2177 struct statfs sfs;
2178
2179 if (statfs(path, &sfs) < 0)
2180 return 0;
2181 else
2182 return sfs.f_bsize * sfs.f_blocks;
2183 }
2184
2185 u64 get_partition_size(const char *dev)
2186 {
2187 u64 result;
2188 int fd = open(dev, O_RDONLY);
2189
2190 if (fd < 0)
2191 return 0;
2192 if (ioctl(fd, BLKGETSIZE64, &result) < 0) {
2193 close(fd);
2194 return 0;
2195 }
2196 close(fd);
2197
2198 return result;
2199 }
2200
2201 /*
2202 * Check if the BTRFS_IOC_TREE_SEARCH_V2 ioctl is supported on a given
2203 * filesystem, opened at fd
2204 */
2205 int btrfs_tree_search2_ioctl_supported(int fd)
2206 {
2207 struct btrfs_ioctl_search_args_v2 *args2;
2208 struct btrfs_ioctl_search_key *sk;
2209 int args2_size = 1024;
2210 char args2_buf[args2_size];
2211 int ret;
2212
2213 args2 = (struct btrfs_ioctl_search_args_v2 *)args2_buf;
2214 sk = &(args2->key);
2215
2216 /*
2217 * Search for the extent tree item in the root tree.
2218 */
2219 sk->tree_id = BTRFS_ROOT_TREE_OBJECTID;
2220 sk->min_objectid = BTRFS_EXTENT_TREE_OBJECTID;
2221 sk->max_objectid = BTRFS_EXTENT_TREE_OBJECTID;
2222 sk->min_type = BTRFS_ROOT_ITEM_KEY;
2223 sk->max_type = BTRFS_ROOT_ITEM_KEY;
2224 sk->min_offset = 0;
2225 sk->max_offset = (u64)-1;
2226 sk->min_transid = 0;
2227 sk->max_transid = (u64)-1;
2228 sk->nr_items = 1;
2229 args2->buf_size = args2_size - sizeof(struct btrfs_ioctl_search_args_v2);
2230 ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH_V2, args2);
2231 if (ret == -EOPNOTSUPP)
2232 return 0;
2233 else if (ret == 0)
2234 return 1;
2235 return ret;
2236 }
2237
2238 int btrfs_check_nodesize(u32 nodesize, u32 sectorsize, u64 features)
2239 {
2240 if (nodesize < sectorsize) {
2241 error("illegal nodesize %u (smaller than %u)",
2242 nodesize, sectorsize);
2243 return -1;
2244 } else if (nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2245 error("illegal nodesize %u (larger than %u)",
2246 nodesize, BTRFS_MAX_METADATA_BLOCKSIZE);
2247 return -1;
2248 } else if (nodesize & (sectorsize - 1)) {
2249 error("illegal nodesize %u (not aligned to %u)",
2250 nodesize, sectorsize);
2251 return -1;
2252 } else if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS &&
2253 nodesize != sectorsize) {
2254 error("illegal nodesize %u (not equal to %u for mixed block group)",
2255 nodesize, sectorsize);
2256 return -1;
2257 }
2258 return 0;
2259 }
2260
2261 /*
2262 * Copy a path argument from SRC to DEST and check the SRC length if it's at
2263 * most PATH_MAX and fits into DEST. DESTLEN is supposed to be exact size of
2264 * the buffer.
2265 * The destination buffer is zero terminated.
2266 * Return < 0 for error, 0 otherwise.
2267 */
2268 int arg_copy_path(char *dest, const char *src, int destlen)
2269 {
2270 size_t len = strlen(src);
2271
2272 if (len >= PATH_MAX || len >= destlen)
2273 return -ENAMETOOLONG;
2274
2275 __strncpy_null(dest, src, destlen);
2276
2277 return 0;
2278 }
2279
2280 unsigned int get_unit_mode_from_arg(int *argc, char *argv[], int df_mode)
2281 {
2282 unsigned int unit_mode = UNITS_DEFAULT;
2283 int arg_i;
2284 int arg_end;
2285
2286 for (arg_i = 0; arg_i < *argc; arg_i++) {
2287 if (!strcmp(argv[arg_i], "--"))
2288 break;
2289
2290 if (!strcmp(argv[arg_i], "--raw")) {
2291 unit_mode = UNITS_RAW;
2292 argv[arg_i] = NULL;
2293 continue;
2294 }
2295 if (!strcmp(argv[arg_i], "--human-readable")) {
2296 unit_mode = UNITS_HUMAN_BINARY;
2297 argv[arg_i] = NULL;
2298 continue;
2299 }
2300
2301 if (!strcmp(argv[arg_i], "--iec")) {
2302 units_set_mode(&unit_mode, UNITS_BINARY);
2303 argv[arg_i] = NULL;
2304 continue;
2305 }
2306 if (!strcmp(argv[arg_i], "--si")) {
2307 units_set_mode(&unit_mode, UNITS_DECIMAL);
2308 argv[arg_i] = NULL;
2309 continue;
2310 }
2311
2312 if (!strcmp(argv[arg_i], "--kbytes")) {
2313 units_set_base(&unit_mode, UNITS_KBYTES);
2314 argv[arg_i] = NULL;
2315 continue;
2316 }
2317 if (!strcmp(argv[arg_i], "--mbytes")) {
2318 units_set_base(&unit_mode, UNITS_MBYTES);
2319 argv[arg_i] = NULL;
2320 continue;
2321 }
2322 if (!strcmp(argv[arg_i], "--gbytes")) {
2323 units_set_base(&unit_mode, UNITS_GBYTES);
2324 argv[arg_i] = NULL;
2325 continue;
2326 }
2327 if (!strcmp(argv[arg_i], "--tbytes")) {
2328 units_set_base(&unit_mode, UNITS_TBYTES);
2329 argv[arg_i] = NULL;
2330 continue;
2331 }
2332
2333 if (!df_mode)
2334 continue;
2335
2336 if (!strcmp(argv[arg_i], "-b")) {
2337 unit_mode = UNITS_RAW;
2338 argv[arg_i] = NULL;
2339 continue;
2340 }
2341 if (!strcmp(argv[arg_i], "-h")) {
2342 unit_mode = UNITS_HUMAN_BINARY;
2343 argv[arg_i] = NULL;
2344 continue;
2345 }
2346 if (!strcmp(argv[arg_i], "-H")) {
2347 unit_mode = UNITS_HUMAN_DECIMAL;
2348 argv[arg_i] = NULL;
2349 continue;
2350 }
2351 if (!strcmp(argv[arg_i], "-k")) {
2352 units_set_base(&unit_mode, UNITS_KBYTES);
2353 argv[arg_i] = NULL;
2354 continue;
2355 }
2356 if (!strcmp(argv[arg_i], "-m")) {
2357 units_set_base(&unit_mode, UNITS_MBYTES);
2358 argv[arg_i] = NULL;
2359 continue;
2360 }
2361 if (!strcmp(argv[arg_i], "-g")) {
2362 units_set_base(&unit_mode, UNITS_GBYTES);
2363 argv[arg_i] = NULL;
2364 continue;
2365 }
2366 if (!strcmp(argv[arg_i], "-t")) {
2367 units_set_base(&unit_mode, UNITS_TBYTES);
2368 argv[arg_i] = NULL;
2369 continue;
2370 }
2371 }
2372
2373 for (arg_i = 0, arg_end = 0; arg_i < *argc; arg_i++) {
2374 if (!argv[arg_i])
2375 continue;
2376 argv[arg_end] = argv[arg_i];
2377 arg_end++;
2378 }
2379
2380 *argc = arg_end;
2381
2382 return unit_mode;
2383 }
2384
2385 u64 div_factor(u64 num, int factor)
2386 {
2387 if (factor == 10)
2388 return num;
2389 num *= factor;
2390 num /= 10;
2391 return num;
2392 }
2393 /*
2394 * Get the length of the string converted from a u64 number.
2395 *
2396 * Result is equal to log10(num) + 1, but without the use of math library.
2397 */
2398 int count_digits(u64 num)
2399 {
2400 int ret = 0;
2401
2402 if (num == 0)
2403 return 1;
2404 while (num > 0) {
2405 ret++;
2406 num /= 10;
2407 }
2408 return ret;
2409 }
2410
2411 int string_is_numerical(const char *str)
2412 {
2413 if (!str)
2414 return 0;
2415 if (!(*str >= '0' && *str <= '9'))
2416 return 0;
2417 while (*str >= '0' && *str <= '9')
2418 str++;
2419 if (*str != '\0')
2420 return 0;
2421 return 1;
2422 }
2423
2424 int prefixcmp(const char *str, const char *prefix)
2425 {
2426 for (; ; str++, prefix++)
2427 if (!*prefix)
2428 return 0;
2429 else if (*str != *prefix)
2430 return (unsigned char)*prefix - (unsigned char)*str;
2431 }
2432
2433 /* Subvolume helper functions */
2434 /*
2435 * test if name is a correct subvolume name
2436 * this function return
2437 * 0-> name is not a correct subvolume name
2438 * 1-> name is a correct subvolume name
2439 */
2440 int test_issubvolname(const char *name)
2441 {
2442 return name[0] != '\0' && !strchr(name, '/') &&
2443 strcmp(name, ".") && strcmp(name, "..");
2444 }
2445
2446 /*
2447 * Test if path is a subvolume
2448 * Returns:
2449 * 0 - path exists but it is not a subvolume
2450 * 1 - path exists and it is a subvolume
2451 * < 0 - error
2452 */
2453 int test_issubvolume(const char *path)
2454 {
2455 struct stat st;
2456 struct statfs stfs;
2457 int res;
2458
2459 res = stat(path, &st);
2460 if (res < 0)
2461 return -errno;
2462
2463 if (st.st_ino != BTRFS_FIRST_FREE_OBJECTID || !S_ISDIR(st.st_mode))
2464 return 0;
2465
2466 res = statfs(path, &stfs);
2467 if (res < 0)
2468 return -errno;
2469
2470 return (int)stfs.f_type == BTRFS_SUPER_MAGIC;
2471 }
2472
2473 const char *subvol_strip_mountpoint(const char *mnt, const char *full_path)
2474 {
2475 int len = strlen(mnt);
2476 if (!len)
2477 return full_path;
2478
2479 if (mnt[len - 1] != '/')
2480 len += 1;
2481
2482 return full_path + len;
2483 }
2484
2485 /*
2486 * Returns
2487 * <0: Std error
2488 * 0: All fine
2489 * 1: Error; and error info printed to the terminal. Fixme.
2490 * 2: If the fullpath is root tree instead of subvol tree
2491 */
2492 int get_subvol_info(const char *fullpath, struct root_info *get_ri)
2493 {
2494 u64 sv_id;
2495 int ret = 1;
2496 int fd = -1;
2497 int mntfd = -1;
2498 char *mnt = NULL;
2499 const char *svpath = NULL;
2500 DIR *dirstream1 = NULL;
2501 DIR *dirstream2 = NULL;
2502
2503 ret = test_issubvolume(fullpath);
2504 if (ret < 0)
2505 return ret;
2506 if (!ret) {
2507 error("not a subvolume: %s", fullpath);
2508 return 1;
2509 }
2510
2511 ret = find_mount_root(fullpath, &mnt);
2512 if (ret < 0)
2513 return ret;
2514 if (ret > 0) {
2515 error("%s doesn't belong to btrfs mount point", fullpath);
2516 return 1;
2517 }
2518 ret = 1;
2519 svpath = subvol_strip_mountpoint(mnt, fullpath);
2520
2521 fd = btrfs_open_dir(fullpath, &dirstream1, 1);
2522 if (fd < 0)
2523 goto out;
2524
2525 ret = btrfs_list_get_path_rootid(fd, &sv_id);
2526 if (ret)
2527 goto out;
2528
2529 mntfd = btrfs_open_dir(mnt, &dirstream2, 1);
2530 if (mntfd < 0)
2531 goto out;
2532
2533 memset(get_ri, 0, sizeof(*get_ri));
2534 get_ri->root_id = sv_id;
2535
2536 if (sv_id == BTRFS_FS_TREE_OBJECTID)
2537 ret = btrfs_get_toplevel_subvol(mntfd, get_ri);
2538 else
2539 ret = btrfs_get_subvol(mntfd, get_ri);
2540 if (ret)
2541 error("can't find '%s': %d", svpath, ret);
2542
2543 out:
2544 close_file_or_dir(mntfd, dirstream2);
2545 close_file_or_dir(fd, dirstream1);
2546 free(mnt);
2547
2548 return ret;
2549 }
2550
2551 int get_subvol_info_by_rootid(const char *mnt, struct root_info *get_ri, u64 r_id)
2552 {
2553 int fd;
2554 int ret;
2555 DIR *dirstream = NULL;
2556
2557 fd = btrfs_open_dir(mnt, &dirstream, 1);
2558 if (fd < 0)
2559 return -EINVAL;
2560
2561 memset(get_ri, 0, sizeof(*get_ri));
2562 get_ri->root_id = r_id;
2563
2564 if (r_id == BTRFS_FS_TREE_OBJECTID)
2565 ret = btrfs_get_toplevel_subvol(fd, get_ri);
2566 else
2567 ret = btrfs_get_subvol(fd, get_ri);
2568
2569 if (ret)
2570 error("can't find rootid '%llu' on '%s': %d", r_id, mnt, ret);
2571
2572 close_file_or_dir(fd, dirstream);
2573
2574 return ret;
2575 }
2576
2577 int get_subvol_info_by_uuid(const char *mnt, struct root_info *get_ri, u8 *uuid_arg)
2578 {
2579 int fd;
2580 int ret;
2581 DIR *dirstream = NULL;
2582
2583 fd = btrfs_open_dir(mnt, &dirstream, 1);
2584 if (fd < 0)
2585 return -EINVAL;
2586
2587 memset(get_ri, 0, sizeof(*get_ri));
2588 uuid_copy(get_ri->uuid, uuid_arg);
2589
2590 ret = btrfs_get_subvol(fd, get_ri);
2591 if (ret) {
2592 char uuid_parsed[BTRFS_UUID_UNPARSED_SIZE];
2593 uuid_unparse(uuid_arg, uuid_parsed);
2594 error("can't find uuid '%s' on '%s': %d",
2595 uuid_parsed, mnt, ret);
2596 }
2597
2598 close_file_or_dir(fd, dirstream);
2599
2600 return ret;
2601 }
2602
2603 /* Set the seed manually */
2604 void init_rand_seed(u64 seed)
2605 {
2606 int i;
2607
2608 /* only use the last 48 bits */
2609 for (i = 0; i < 3; i++) {
2610 rand_seed[i] = (unsigned short)(seed ^ (unsigned short)(-1));
2611 seed >>= 16;
2612 }
2613 rand_seed_initlized = 1;
2614 }
2615
2616 static void __init_seed(void)
2617 {
2618 struct timeval tv;
2619 int ret;
2620 int fd;
2621
2622 if(rand_seed_initlized)
2623 return;
2624 /* Use urandom as primary seed source. */
2625 fd = open("/dev/urandom", O_RDONLY);
2626 if (fd >= 0) {
2627 ret = read(fd, rand_seed, sizeof(rand_seed));
2628 close(fd);
2629 if (ret < sizeof(rand_seed))
2630 goto fallback;
2631 } else {
2632 fallback:
2633 /* Use time and pid as fallback seed */
2634 warning("failed to read /dev/urandom, use time and pid as random seed");
2635 gettimeofday(&tv, 0);
2636 rand_seed[0] = getpid() ^ (tv.tv_sec & 0xFFFF);
2637 rand_seed[1] = getppid() ^ (tv.tv_usec & 0xFFFF);
2638 rand_seed[2] = (tv.tv_sec ^ tv.tv_usec) >> 16;
2639 }
2640 rand_seed_initlized = 1;
2641 }
2642
2643 u32 rand_u32(void)
2644 {
2645 __init_seed();
2646 /*
2647 * Don't use nrand48, its range is [0,2^31) The highest bit will alwasy
2648 * be 0. Use jrand48 to include the highest bit.
2649 */
2650 return (u32)jrand48(rand_seed);
2651 }
2652
2653 /* Return random number in range [0, upper) */
2654 unsigned int rand_range(unsigned int upper)
2655 {
2656 __init_seed();
2657 /*
2658 * Use the full 48bits to mod, which would be more uniformly
2659 * distributed
2660 */
2661 return (unsigned int)(jrand48(rand_seed) % upper);
2662 }
2663
2664 int rand_int(void)
2665 {
2666 return (int)(rand_u32());
2667 }
2668
2669 u64 rand_u64(void)
2670 {
2671 u64 ret = 0;
2672
2673 ret += rand_u32();
2674 ret <<= 32;
2675 ret += rand_u32();
2676 return ret;
2677 }
2678
2679 u16 rand_u16(void)
2680 {
2681 return (u16)(rand_u32());
2682 }
2683
2684 u8 rand_u8(void)
2685 {
2686 return (u8)(rand_u32());
2687 }
2688
2689 void btrfs_config_init(void)
2690 {
2691 }
2692
2693 /* Returns total size of main memory in bytes, -1UL if error. */
2694 unsigned long total_memory(void)
2695 {
2696 struct sysinfo si;
2697
2698 if (sysinfo(&si) < 0) {
2699 error("can't determine memory size");
2700 return -1UL;
2701 }
2702 return si.totalram * si.mem_unit; /* bytes */
2703 }
(deprecated) Btrfs progs developments and patch integration