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Btrfs progs v4.17.1
[btrfs-progs-unstable/devel.git] / utils.c
blobd4395b1f32f8ba4563289b79ccab5ba0aa6d91c9
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 <btrfsutil.h>
44
45 #include "kerncompat.h"
46 #include "radix-tree.h"
47 #include "ctree.h"
48 #include "disk-io.h"
49 #include "transaction.h"
50 #include "crc32c.h"
51 #include "utils.h"
52 #include "volumes.h"
53 #include "ioctl.h"
54 #include "commands.h"
55 #include "mkfs/common.h"
56
57 #ifndef BLKDISCARD
58 #define BLKDISCARD _IO(0x12,119)
59 #endif
60
61 static int btrfs_scan_done = 0;
62
63 static int rand_seed_initlized = 0;
64 static unsigned short rand_seed[3];
65
66 struct btrfs_config bconf;
67
68 /*
69 * Discard the given range in one go
70 */
71 static int discard_range(int fd, u64 start, u64 len)
72 {
73 u64 range[2] = { start, len };
74
75 if (ioctl(fd, BLKDISCARD, &range) < 0)
76 return errno;
77 return 0;
78 }
79
80 /*
81 * Discard blocks in the given range in 1G chunks, the process is interruptible
82 */
83 static int discard_blocks(int fd, u64 start, u64 len)
84 {
85 while (len > 0) {
86 /* 1G granularity */
87 u64 chunk_size = min_t(u64, len, SZ_1G);
88 int ret;
89
90 ret = discard_range(fd, start, chunk_size);
91 if (ret)
92 return ret;
93 len -= chunk_size;
94 start += chunk_size;
95 }
96
97 return 0;
98 }
99
100 int test_uuid_unique(char *fs_uuid)
101 {
102 int unique = 1;
103 blkid_dev_iterate iter = NULL;
104 blkid_dev dev = NULL;
105 blkid_cache cache = NULL;
106
107 if (blkid_get_cache(&cache, NULL) < 0) {
108 printf("ERROR: lblkid cache get failed\n");
109 return 1;
110 }
111 blkid_probe_all(cache);
112 iter = blkid_dev_iterate_begin(cache);
113 blkid_dev_set_search(iter, "UUID", fs_uuid);
114
115 while (blkid_dev_next(iter, &dev) == 0) {
116 dev = blkid_verify(cache, dev);
117 if (dev) {
118 unique = 0;
119 break;
120 }
121 }
122
123 blkid_dev_iterate_end(iter);
124 blkid_put_cache(cache);
125
126 return unique;
127 }
128
129 u64 btrfs_device_size(int fd, struct stat *st)
130 {
131 u64 size;
132 if (S_ISREG(st->st_mode)) {
133 return st->st_size;
134 }
135 if (!S_ISBLK(st->st_mode)) {
136 return 0;
137 }
138 if (ioctl(fd, BLKGETSIZE64, &size) >= 0) {
139 return size;
140 }
141 return 0;
142 }
143
144 static int zero_blocks(int fd, off_t start, size_t len)
145 {
146 char *buf = malloc(len);
147 int ret = 0;
148 ssize_t written;
149
150 if (!buf)
151 return -ENOMEM;
152 memset(buf, 0, len);
153 written = pwrite(fd, buf, len, start);
154 if (written != len)
155 ret = -EIO;
156 free(buf);
157 return ret;
158 }
159
160 #define ZERO_DEV_BYTES SZ_2M
161
162 /* don't write outside the device by clamping the region to the device size */
163 static int zero_dev_clamped(int fd, off_t start, ssize_t len, u64 dev_size)
164 {
165 off_t end = max(start, start + len);
166
167 #ifdef __sparc__
168 /* and don't overwrite the disk labels on sparc */
169 start = max(start, 1024);
170 end = max(end, 1024);
171 #endif
172
173 start = min_t(u64, start, dev_size);
174 end = min_t(u64, end, dev_size);
175
176 return zero_blocks(fd, start, end - start);
177 }
178
179 int btrfs_add_to_fsid(struct btrfs_trans_handle *trans,
180 struct btrfs_root *root, int fd, const char *path,
181 u64 device_total_bytes, u32 io_width, u32 io_align,
182 u32 sectorsize)
183 {
184 struct btrfs_super_block *disk_super;
185 struct btrfs_fs_info *fs_info = root->fs_info;
186 struct btrfs_super_block *super = fs_info->super_copy;
187 struct btrfs_device *device;
188 struct btrfs_dev_item *dev_item;
189 char *buf = NULL;
190 u64 fs_total_bytes;
191 u64 num_devs;
192 int ret;
193
194 device_total_bytes = (device_total_bytes / sectorsize) * sectorsize;
195
196 device = calloc(1, sizeof(*device));
197 if (!device) {
198 ret = -ENOMEM;
199 goto out;
200 }
201 buf = calloc(1, sectorsize);
202 if (!buf) {
203 ret = -ENOMEM;
204 goto out;
205 }
206
207 disk_super = (struct btrfs_super_block *)buf;
208 dev_item = &disk_super->dev_item;
209
210 uuid_generate(device->uuid);
211 device->devid = 0;
212 device->type = 0;
213 device->io_width = io_width;
214 device->io_align = io_align;
215 device->sector_size = sectorsize;
216 device->fd = fd;
217 device->writeable = 1;
218 device->total_bytes = device_total_bytes;
219 device->bytes_used = 0;
220 device->total_ios = 0;
221 device->dev_root = fs_info->dev_root;
222 device->name = strdup(path);
223 if (!device->name) {
224 ret = -ENOMEM;
225 goto out;
226 }
227
228 INIT_LIST_HEAD(&device->dev_list);
229 ret = btrfs_add_device(trans, fs_info, device);
230 if (ret)
231 goto out;
232
233 fs_total_bytes = btrfs_super_total_bytes(super) + device_total_bytes;
234 btrfs_set_super_total_bytes(super, fs_total_bytes);
235
236 num_devs = btrfs_super_num_devices(super) + 1;
237 btrfs_set_super_num_devices(super, num_devs);
238
239 memcpy(disk_super, super, sizeof(*disk_super));
240
241 btrfs_set_super_bytenr(disk_super, BTRFS_SUPER_INFO_OFFSET);
242 btrfs_set_stack_device_id(dev_item, device->devid);
243 btrfs_set_stack_device_type(dev_item, device->type);
244 btrfs_set_stack_device_io_align(dev_item, device->io_align);
245 btrfs_set_stack_device_io_width(dev_item, device->io_width);
246 btrfs_set_stack_device_sector_size(dev_item, device->sector_size);
247 btrfs_set_stack_device_total_bytes(dev_item, device->total_bytes);
248 btrfs_set_stack_device_bytes_used(dev_item, device->bytes_used);
249 memcpy(&dev_item->uuid, device->uuid, BTRFS_UUID_SIZE);
250
251 ret = pwrite(fd, buf, sectorsize, BTRFS_SUPER_INFO_OFFSET);
252 BUG_ON(ret != sectorsize);
253
254 free(buf);
255 list_add(&device->dev_list, &fs_info->fs_devices->devices);
256 device->fs_devices = fs_info->fs_devices;
257 return 0;
258
259 out:
260 free(device);
261 free(buf);
262 return ret;
263 }
264
265 static int btrfs_wipe_existing_sb(int fd)
266 {
267 const char *off = NULL;
268 size_t len = 0;
269 loff_t offset;
270 char buf[BUFSIZ];
271 int ret = 0;
272 blkid_probe pr = NULL;
273
274 pr = blkid_new_probe();
275 if (!pr)
276 return -1;
277
278 if (blkid_probe_set_device(pr, fd, 0, 0)) {
279 ret = -1;
280 goto out;
281 }
282
283 ret = blkid_probe_lookup_value(pr, "SBMAGIC_OFFSET", &off, NULL);
284 if (!ret)
285 ret = blkid_probe_lookup_value(pr, "SBMAGIC", NULL, &len);
286
287 if (ret || len == 0 || off == NULL) {
288 /*
289 * If lookup fails, the probe did not find any values, eg. for
290 * a file image or a loop device. Soft error.
291 */
292 ret = 1;
293 goto out;
294 }
295
296 offset = strtoll(off, NULL, 10);
297 if (len > sizeof(buf))
298 len = sizeof(buf);
299
300 memset(buf, 0, len);
301 ret = pwrite(fd, buf, len, offset);
302 if (ret < 0) {
303 error("cannot wipe existing superblock: %m");
304 ret = -1;
305 } else if (ret != len) {
306 error("cannot wipe existing superblock: wrote %d of %zd", ret, len);
307 ret = -1;
308 }
309 fsync(fd);
310
311 out:
312 blkid_free_probe(pr);
313 return ret;
314 }
315
316 int btrfs_prepare_device(int fd, const char *file, u64 *block_count_ret,
317 u64 max_block_count, unsigned opflags)
318 {
319 u64 block_count;
320 struct stat st;
321 int i, ret;
322
323 ret = fstat(fd, &st);
324 if (ret < 0) {
325 error("unable to stat %s: %m", file);
326 return 1;
327 }
328
329 block_count = btrfs_device_size(fd, &st);
330 if (block_count == 0) {
331 error("unable to determine size of %s", file);
332 return 1;
333 }
334 if (max_block_count)
335 block_count = min(block_count, max_block_count);
336
337 if (opflags & PREP_DEVICE_DISCARD) {
338 /*
339 * We intentionally ignore errors from the discard ioctl. It
340 * is not necessary for the mkfs functionality but just an
341 * optimization.
342 */
343 if (discard_range(fd, 0, 0) == 0) {
344 if (opflags & PREP_DEVICE_VERBOSE)
345 printf("Performing full device TRIM %s (%s) ...\n",
346 file, pretty_size(block_count));
347 discard_blocks(fd, 0, block_count);
348 }
349 }
350
351 ret = zero_dev_clamped(fd, 0, ZERO_DEV_BYTES, block_count);
352 for (i = 0 ; !ret && i < BTRFS_SUPER_MIRROR_MAX; i++)
353 ret = zero_dev_clamped(fd, btrfs_sb_offset(i),
354 BTRFS_SUPER_INFO_SIZE, block_count);
355 if (!ret && (opflags & PREP_DEVICE_ZERO_END))
356 ret = zero_dev_clamped(fd, block_count - ZERO_DEV_BYTES,
357 ZERO_DEV_BYTES, block_count);
358
359 if (ret < 0) {
360 error("failed to zero device '%s': %s", file, strerror(-ret));
361 return 1;
362 }
363
364 ret = btrfs_wipe_existing_sb(fd);
365 if (ret < 0) {
366 error("cannot wipe superblocks on %s", file);
367 return 1;
368 }
369
370 *block_count_ret = block_count;
371 return 0;
372 }
373
374 int btrfs_make_root_dir(struct btrfs_trans_handle *trans,
375 struct btrfs_root *root, u64 objectid)
376 {
377 int ret;
378 struct btrfs_inode_item inode_item;
379 time_t now = time(NULL);
380
381 memset(&inode_item, 0, sizeof(inode_item));
382 btrfs_set_stack_inode_generation(&inode_item, trans->transid);
383 btrfs_set_stack_inode_size(&inode_item, 0);
384 btrfs_set_stack_inode_nlink(&inode_item, 1);
385 btrfs_set_stack_inode_nbytes(&inode_item, root->fs_info->nodesize);
386 btrfs_set_stack_inode_mode(&inode_item, S_IFDIR | 0755);
387 btrfs_set_stack_timespec_sec(&inode_item.atime, now);
388 btrfs_set_stack_timespec_nsec(&inode_item.atime, 0);
389 btrfs_set_stack_timespec_sec(&inode_item.ctime, now);
390 btrfs_set_stack_timespec_nsec(&inode_item.ctime, 0);
391 btrfs_set_stack_timespec_sec(&inode_item.mtime, now);
392 btrfs_set_stack_timespec_nsec(&inode_item.mtime, 0);
393 btrfs_set_stack_timespec_sec(&inode_item.otime, now);
394 btrfs_set_stack_timespec_nsec(&inode_item.otime, 0);
395
396 if (root->fs_info->tree_root == root)
397 btrfs_set_super_root_dir(root->fs_info->super_copy, objectid);
398
399 ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
400 if (ret)
401 goto error;
402
403 ret = btrfs_insert_inode_ref(trans, root, "..", 2, objectid, objectid, 0);
404 if (ret)
405 goto error;
406
407 btrfs_set_root_dirid(&root->root_item, objectid);
408 ret = 0;
409 error:
410 return ret;
411 }
412
413 /*
414 * checks if a path is a block device node
415 * Returns negative errno on failure, otherwise
416 * returns 1 for blockdev, 0 for not-blockdev
417 */
418 int is_block_device(const char *path)
419 {
420 struct stat statbuf;
421
422 if (stat(path, &statbuf) < 0)
423 return -errno;
424
425 return !!S_ISBLK(statbuf.st_mode);
426 }
427
428 /*
429 * check if given path is a mount point
430 * return 1 if yes. 0 if no. -1 for error
431 */
432 int is_mount_point(const char *path)
433 {
434 FILE *f;
435 struct mntent *mnt;
436 int ret = 0;
437
438 f = setmntent("/proc/self/mounts", "r");
439 if (f == NULL)
440 return -1;
441
442 while ((mnt = getmntent(f)) != NULL) {
443 if (strcmp(mnt->mnt_dir, path))
444 continue;
445 ret = 1;
446 break;
447 }
448 endmntent(f);
449 return ret;
450 }
451
452 int is_reg_file(const char *path)
453 {
454 struct stat statbuf;
455
456 if (stat(path, &statbuf) < 0)
457 return -errno;
458 return S_ISREG(statbuf.st_mode);
459 }
460
461 int is_path_exist(const char *path)
462 {
463 struct stat statbuf;
464 int ret;
465
466 ret = stat(path, &statbuf);
467 if (ret < 0) {
468 if (errno == ENOENT)
469 return 0;
470 else
471 return -errno;
472 }
473 return 1;
474 }
475
476 /*
477 * This function checks if the given input parameter is
478 * an uuid or a path
479 * return <0 : some error in the given input
480 * return BTRFS_ARG_UNKNOWN: unknown input
481 * return BTRFS_ARG_UUID: given input is uuid
482 * return BTRFS_ARG_MNTPOINT: given input is path
483 * return BTRFS_ARG_REG: given input is regular file
484 * return BTRFS_ARG_BLKDEV: given input is block device
485 */
486 int check_arg_type(const char *input)
487 {
488 uuid_t uuid;
489 char path[PATH_MAX];
490
491 if (!input)
492 return -EINVAL;
493
494 if (realpath(input, path)) {
495 if (is_block_device(path) == 1)
496 return BTRFS_ARG_BLKDEV;
497
498 if (is_mount_point(path) == 1)
499 return BTRFS_ARG_MNTPOINT;
500
501 if (is_reg_file(path))
502 return BTRFS_ARG_REG;
503
504 return BTRFS_ARG_UNKNOWN;
505 }
506
507 if (strlen(input) == (BTRFS_UUID_UNPARSED_SIZE - 1) &&
508 !uuid_parse(input, uuid))
509 return BTRFS_ARG_UUID;
510
511 return BTRFS_ARG_UNKNOWN;
512 }
513
514 /*
515 * Find the mount point for a mounted device.
516 * On success, returns 0 with mountpoint in *mp.
517 * On failure, returns -errno (not mounted yields -EINVAL)
518 * Is noisy on failures, expects to be given a mounted device.
519 */
520 int get_btrfs_mount(const char *dev, char *mp, size_t mp_size)
521 {
522 int ret;
523 int fd = -1;
524
525 ret = is_block_device(dev);
526 if (ret <= 0) {
527 if (!ret) {
528 error("not a block device: %s", dev);
529 ret = -EINVAL;
530 } else {
531 error("cannot check %s: %s", dev, strerror(-ret));
532 }
533 goto out;
534 }
535
536 fd = open(dev, O_RDONLY);
537 if (fd < 0) {
538 ret = -errno;
539 error("cannot open %s: %m", dev);
540 goto out;
541 }
542
543 ret = check_mounted_where(fd, dev, mp, mp_size, NULL, SBREAD_DEFAULT);
544 if (!ret) {
545 ret = -EINVAL;
546 } else { /* mounted, all good */
547 ret = 0;
548 }
549 out:
550 if (fd != -1)
551 close(fd);
552 return ret;
553 }
554
555 /*
556 * Given a pathname, return a filehandle to:
557 * the original pathname or,
558 * if the pathname is a mounted btrfs device, to its mountpoint.
559 *
560 * On error, return -1, errno should be set.
561 */
562 int open_path_or_dev_mnt(const char *path, DIR **dirstream, int verbose)
563 {
564 char mp[PATH_MAX];
565 int ret;
566
567 if (is_block_device(path)) {
568 ret = get_btrfs_mount(path, mp, sizeof(mp));
569 if (ret < 0) {
570 /* not a mounted btrfs dev */
571 error_on(verbose, "'%s' is not a mounted btrfs device",
572 path);
573 errno = EINVAL;
574 return -1;
575 }
576 ret = open_file_or_dir(mp, dirstream);
577 error_on(verbose && ret < 0, "can't access '%s': %m",
578 path);
579 } else {
580 ret = btrfs_open_dir(path, dirstream, 1);
581 }
582
583 return ret;
584 }
585
586 /*
587 * Do the following checks before calling open_file_or_dir():
588 * 1: path is in a btrfs filesystem
589 * 2: path is a directory if dir_only is 1
590 */
591 int btrfs_open(const char *path, DIR **dirstream, int verbose, int dir_only)
592 {
593 struct statfs stfs;
594 struct stat st;
595 int ret;
596
597 if (statfs(path, &stfs) != 0) {
598 error_on(verbose, "cannot access '%s': %m", path);
599 return -1;
600 }
601
602 if (stfs.f_type != BTRFS_SUPER_MAGIC) {
603 error_on(verbose, "not a btrfs filesystem: %s", path);
604 return -2;
605 }
606
607 if (stat(path, &st) != 0) {
608 error_on(verbose, "cannot access '%s': %m", path);
609 return -1;
610 }
611
612 if (dir_only && !S_ISDIR(st.st_mode)) {
613 error_on(verbose, "not a directory: %s", path);
614 return -3;
615 }
616
617 ret = open_file_or_dir(path, dirstream);
618 if (ret < 0) {
619 error_on(verbose, "cannot access '%s': %m", path);
620 }
621
622 return ret;
623 }
624
625 int btrfs_open_dir(const char *path, DIR **dirstream, int verbose)
626 {
627 return btrfs_open(path, dirstream, verbose, 1);
628 }
629
630 int btrfs_open_file_or_dir(const char *path, DIR **dirstream, int verbose)
631 {
632 return btrfs_open(path, dirstream, verbose, 0);
633 }
634
635 /* checks if a device is a loop device */
636 static int is_loop_device (const char* device) {
637 struct stat statbuf;
638
639 if(stat(device, &statbuf) < 0)
640 return -errno;
641
642 return (S_ISBLK(statbuf.st_mode) &&
643 MAJOR(statbuf.st_rdev) == LOOP_MAJOR);
644 }
645
646 /*
647 * Takes a loop device path (e.g. /dev/loop0) and returns
648 * the associated file (e.g. /images/my_btrfs.img) using
649 * loopdev API
650 */
651 static int resolve_loop_device_with_loopdev(const char* loop_dev, char* loop_file)
652 {
653 int fd;
654 int ret;
655 struct loop_info64 lo64;
656
657 fd = open(loop_dev, O_RDONLY | O_NONBLOCK);
658 if (fd < 0)
659 return -errno;
660 ret = ioctl(fd, LOOP_GET_STATUS64, &lo64);
661 if (ret < 0) {
662 ret = -errno;
663 goto out;
664 }
665
666 memcpy(loop_file, lo64.lo_file_name, sizeof(lo64.lo_file_name));
667 loop_file[sizeof(lo64.lo_file_name)] = 0;
668
669 out:
670 close(fd);
671
672 return ret;
673 }
674
675 /* Takes a loop device path (e.g. /dev/loop0) and returns
676 * the associated file (e.g. /images/my_btrfs.img) */
677 static int resolve_loop_device(const char* loop_dev, char* loop_file,
678 int max_len)
679 {
680 int ret;
681 FILE *f;
682 char fmt[20];
683 char p[PATH_MAX];
684 char real_loop_dev[PATH_MAX];
685
686 if (!realpath(loop_dev, real_loop_dev))
687 return -errno;
688 snprintf(p, PATH_MAX, "/sys/block/%s/loop/backing_file", strrchr(real_loop_dev, '/'));
689 if (!(f = fopen(p, "r"))) {
690 if (errno == ENOENT)
691 /*
692 * It's possibly a partitioned loop device, which is
693 * resolvable with loopdev API.
694 */
695 return resolve_loop_device_with_loopdev(loop_dev, loop_file);
696 return -errno;
697 }
698
699 snprintf(fmt, 20, "%%%i[^\n]", max_len-1);
700 ret = fscanf(f, fmt, loop_file);
701 fclose(f);
702 if (ret == EOF)
703 return -errno;
704
705 return 0;
706 }
707
708 /*
709 * Checks whether a and b are identical or device
710 * files associated with the same block device
711 */
712 static int is_same_blk_file(const char* a, const char* b)
713 {
714 struct stat st_buf_a, st_buf_b;
715 char real_a[PATH_MAX];
716 char real_b[PATH_MAX];
717
718 if (!realpath(a, real_a))
719 strncpy_null(real_a, a);
720
721 if (!realpath(b, real_b))
722 strncpy_null(real_b, b);
723
724 /* Identical path? */
725 if (strcmp(real_a, real_b) == 0)
726 return 1;
727
728 if (stat(a, &st_buf_a) < 0 || stat(b, &st_buf_b) < 0) {
729 if (errno == ENOENT)
730 return 0;
731 return -errno;
732 }
733
734 /* Same blockdevice? */
735 if (S_ISBLK(st_buf_a.st_mode) && S_ISBLK(st_buf_b.st_mode) &&
736 st_buf_a.st_rdev == st_buf_b.st_rdev) {
737 return 1;
738 }
739
740 /* Hardlink? */
741 if (st_buf_a.st_dev == st_buf_b.st_dev &&
742 st_buf_a.st_ino == st_buf_b.st_ino) {
743 return 1;
744 }
745
746 return 0;
747 }
748
749 /* checks if a and b are identical or device
750 * files associated with the same block device or
751 * if one file is a loop device that uses the other
752 * file.
753 */
754 static int is_same_loop_file(const char* a, const char* b)
755 {
756 char res_a[PATH_MAX];
757 char res_b[PATH_MAX];
758 const char* final_a = NULL;
759 const char* final_b = NULL;
760 int ret;
761
762 /* Resolve a if it is a loop device */
763 if((ret = is_loop_device(a)) < 0) {
764 if (ret == -ENOENT)
765 return 0;
766 return ret;
767 } else if (ret) {
768 ret = resolve_loop_device(a, res_a, sizeof(res_a));
769 if (ret < 0) {
770 if (errno != EPERM)
771 return ret;
772 } else {
773 final_a = res_a;
774 }
775 } else {
776 final_a = a;
777 }
778
779 /* Resolve b if it is a loop device */
780 if ((ret = is_loop_device(b)) < 0) {
781 if (ret == -ENOENT)
782 return 0;
783 return ret;
784 } else if (ret) {
785 ret = resolve_loop_device(b, res_b, sizeof(res_b));
786 if (ret < 0) {
787 if (errno != EPERM)
788 return ret;
789 } else {
790 final_b = res_b;
791 }
792 } else {
793 final_b = b;
794 }
795
796 return is_same_blk_file(final_a, final_b);
797 }
798
799 /* Checks if a file exists and is a block or regular file*/
800 static int is_existing_blk_or_reg_file(const char* filename)
801 {
802 struct stat st_buf;
803
804 if(stat(filename, &st_buf) < 0) {
805 if(errno == ENOENT)
806 return 0;
807 else
808 return -errno;
809 }
810
811 return (S_ISBLK(st_buf.st_mode) || S_ISREG(st_buf.st_mode));
812 }
813
814 /* Checks if a file is used (directly or indirectly via a loop device)
815 * by a device in fs_devices
816 */
817 static int blk_file_in_dev_list(struct btrfs_fs_devices* fs_devices,
818 const char* file)
819 {
820 int ret;
821 struct btrfs_device *device;
822
823 list_for_each_entry(device, &fs_devices->devices, dev_list) {
824 if((ret = is_same_loop_file(device->name, file)))
825 return ret;
826 }
827
828 return 0;
829 }
830
831 /*
832 * Resolve a pathname to a device mapper node to /dev/mapper/<name>
833 * Returns NULL on invalid input or malloc failure; Other failures
834 * will be handled by the caller using the input pathame.
835 */
836 char *canonicalize_dm_name(const char *ptname)
837 {
838 FILE *f;
839 size_t sz;
840 char path[PATH_MAX], name[PATH_MAX], *res = NULL;
841
842 if (!ptname || !*ptname)
843 return NULL;
844
845 snprintf(path, sizeof(path), "/sys/block/%s/dm/name", ptname);
846 if (!(f = fopen(path, "r")))
847 return NULL;
848
849 /* read <name>\n from sysfs */
850 if (fgets(name, sizeof(name), f) && (sz = strlen(name)) > 1) {
851 name[sz - 1] = '\0';
852 snprintf(path, sizeof(path), "/dev/mapper/%s", name);
853
854 if (access(path, F_OK) == 0)
855 res = strdup(path);
856 }
857 fclose(f);
858 return res;
859 }
860
861 /*
862 * Resolve a pathname to a canonical device node, e.g. /dev/sda1 or
863 * to a device mapper pathname.
864 * Returns NULL on invalid input or malloc failure; Other failures
865 * will be handled by the caller using the input pathame.
866 */
867 char *canonicalize_path(const char *path)
868 {
869 char *canonical, *p;
870
871 if (!path || !*path)
872 return NULL;
873
874 canonical = realpath(path, NULL);
875 if (!canonical)
876 return strdup(path);
877 p = strrchr(canonical, '/');
878 if (p && strncmp(p, "/dm-", 4) == 0 && isdigit(*(p + 4))) {
879 char *dm = canonicalize_dm_name(p + 1);
880
881 if (dm) {
882 free(canonical);
883 return dm;
884 }
885 }
886 return canonical;
887 }
888
889 /*
890 * returns 1 if the device was mounted, < 0 on error or 0 if everything
891 * is safe to continue.
892 */
893 int check_mounted(const char* file)
894 {
895 int fd;
896 int ret;
897
898 fd = open(file, O_RDONLY);
899 if (fd < 0) {
900 error("mount check: cannot open %s: %m", file);
901 return -errno;
902 }
903
904 ret = check_mounted_where(fd, file, NULL, 0, NULL, SBREAD_DEFAULT);
905 close(fd);
906
907 return ret;
908 }
909
910 int check_mounted_where(int fd, const char *file, char *where, int size,
911 struct btrfs_fs_devices **fs_dev_ret, unsigned sbflags)
912 {
913 int ret;
914 u64 total_devs = 1;
915 int is_btrfs;
916 struct btrfs_fs_devices *fs_devices_mnt = NULL;
917 FILE *f;
918 struct mntent *mnt;
919
920 /* scan the initial device */
921 ret = btrfs_scan_one_device(fd, file, &fs_devices_mnt,
922 &total_devs, BTRFS_SUPER_INFO_OFFSET, sbflags);
923 is_btrfs = (ret >= 0);
924
925 /* scan other devices */
926 if (is_btrfs && total_devs > 1) {
927 ret = btrfs_scan_devices();
928 if (ret)
929 return ret;
930 }
931
932 /* iterate over the list of currently mounted filesystems */
933 if ((f = setmntent ("/proc/self/mounts", "r")) == NULL)
934 return -errno;
935
936 while ((mnt = getmntent (f)) != NULL) {
937 if(is_btrfs) {
938 if(strcmp(mnt->mnt_type, "btrfs") != 0)
939 continue;
940
941 ret = blk_file_in_dev_list(fs_devices_mnt, mnt->mnt_fsname);
942 } else {
943 /* ignore entries in the mount table that are not
944 associated with a file*/
945 if((ret = is_existing_blk_or_reg_file(mnt->mnt_fsname)) < 0)
946 goto out_mntloop_err;
947 else if(!ret)
948 continue;
949
950 ret = is_same_loop_file(file, mnt->mnt_fsname);
951 }
952
953 if(ret < 0)
954 goto out_mntloop_err;
955 else if(ret)
956 break;
957 }
958
959 /* Did we find an entry in mnt table? */
960 if (mnt && size && where) {
961 strncpy(where, mnt->mnt_dir, size);
962 where[size-1] = 0;
963 }
964 if (fs_dev_ret)
965 *fs_dev_ret = fs_devices_mnt;
966
967 ret = (mnt != NULL);
968
969 out_mntloop_err:
970 endmntent (f);
971
972 return ret;
973 }
974
975 struct pending_dir {
976 struct list_head list;
977 char name[PATH_MAX];
978 };
979
980 int btrfs_register_one_device(const char *fname)
981 {
982 struct btrfs_ioctl_vol_args args;
983 int fd;
984 int ret;
985
986 fd = open("/dev/btrfs-control", O_RDWR);
987 if (fd < 0) {
988 warning(
989 "failed to open /dev/btrfs-control, skipping device registration: %m");
990 return -errno;
991 }
992 memset(&args, 0, sizeof(args));
993 strncpy_null(args.name, fname);
994 ret = ioctl(fd, BTRFS_IOC_SCAN_DEV, &args);
995 if (ret < 0) {
996 error("device scan failed on '%s': %m", fname);
997 ret = -errno;
998 }
999 close(fd);
1000 return ret;
1001 }
1002
1003 /*
1004 * Register all devices in the fs_uuid list created in the user
1005 * space. Ensure btrfs_scan_devices() is called before this func.
1006 */
1007 int btrfs_register_all_devices(void)
1008 {
1009 int err = 0;
1010 int ret = 0;
1011 struct btrfs_fs_devices *fs_devices;
1012 struct btrfs_device *device;
1013 struct list_head *all_uuids;
1014
1015 all_uuids = btrfs_scanned_uuids();
1016
1017 list_for_each_entry(fs_devices, all_uuids, list) {
1018 list_for_each_entry(device, &fs_devices->devices, dev_list) {
1019 if (*device->name)
1020 err = btrfs_register_one_device(device->name);
1021
1022 if (err)
1023 ret++;
1024 }
1025 }
1026
1027 return ret;
1028 }
1029
1030 int btrfs_device_already_in_root(struct btrfs_root *root, int fd,
1031 int super_offset)
1032 {
1033 struct btrfs_super_block *disk_super;
1034 char *buf;
1035 int ret = 0;
1036
1037 buf = malloc(BTRFS_SUPER_INFO_SIZE);
1038 if (!buf) {
1039 ret = -ENOMEM;
1040 goto out;
1041 }
1042 ret = pread(fd, buf, BTRFS_SUPER_INFO_SIZE, super_offset);
1043 if (ret != BTRFS_SUPER_INFO_SIZE)
1044 goto brelse;
1045
1046 ret = 0;
1047 disk_super = (struct btrfs_super_block *)buf;
1048 /*
1049 * Accept devices from the same filesystem, allow partially created
1050 * structures.
1051 */
1052 if (btrfs_super_magic(disk_super) != BTRFS_MAGIC &&
1053 btrfs_super_magic(disk_super) != BTRFS_MAGIC_TEMPORARY)
1054 goto brelse;
1055
1056 if (!memcmp(disk_super->fsid, root->fs_info->super_copy->fsid,
1057 BTRFS_FSID_SIZE))
1058 ret = 1;
1059 brelse:
1060 free(buf);
1061 out:
1062 return ret;
1063 }
1064
1065 /*
1066 * Note: this function uses a static per-thread buffer. Do not call this
1067 * function more than 10 times within one argument list!
1068 */
1069 const char *pretty_size_mode(u64 size, unsigned mode)
1070 {
1071 static __thread int ps_index = 0;
1072 static __thread char ps_array[10][32];
1073 char *ret;
1074
1075 ret = ps_array[ps_index];
1076 ps_index++;
1077 ps_index %= 10;
1078 (void)pretty_size_snprintf(size, ret, 32, mode);
1079
1080 return ret;
1081 }
1082
1083 static const char* unit_suffix_binary[] =
1084 { "B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"};
1085 static const char* unit_suffix_decimal[] =
1086 { "B", "kB", "MB", "GB", "TB", "PB", "EB"};
1087
1088 int pretty_size_snprintf(u64 size, char *str, size_t str_size, unsigned unit_mode)
1089 {
1090 int num_divs;
1091 float fraction;
1092 u64 base = 0;
1093 int mult = 0;
1094 const char** suffix = NULL;
1095 u64 last_size;
1096 int negative;
1097
1098 if (str_size == 0)
1099 return 0;
1100
1101 negative = !!(unit_mode & UNITS_NEGATIVE);
1102 unit_mode &= ~UNITS_NEGATIVE;
1103
1104 if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_RAW) {
1105 if (negative)
1106 snprintf(str, str_size, "%lld", size);
1107 else
1108 snprintf(str, str_size, "%llu", size);
1109 return 0;
1110 }
1111
1112 if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_BINARY) {
1113 base = 1024;
1114 mult = 1024;
1115 suffix = unit_suffix_binary;
1116 } else if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_DECIMAL) {
1117 base = 1000;
1118 mult = 1000;
1119 suffix = unit_suffix_decimal;
1120 }
1121
1122 /* Unknown mode */
1123 if (!base) {
1124 fprintf(stderr, "INTERNAL ERROR: unknown unit base, mode %d\n",
1125 unit_mode);
1126 assert(0);
1127 return -1;
1128 }
1129
1130 num_divs = 0;
1131 last_size = size;
1132 switch (unit_mode & UNITS_MODE_MASK) {
1133 case UNITS_TBYTES: base *= mult; num_divs++;
1134 case UNITS_GBYTES: base *= mult; num_divs++;
1135 case UNITS_MBYTES: base *= mult; num_divs++;
1136 case UNITS_KBYTES: num_divs++;
1137 break;
1138 case UNITS_BYTES:
1139 base = 1;
1140 num_divs = 0;
1141 break;
1142 default:
1143 if (negative) {
1144 s64 ssize = (s64)size;
1145 s64 last_ssize = ssize;
1146
1147 while ((ssize < 0 ? -ssize : ssize) >= mult) {
1148 last_ssize = ssize;
1149 ssize /= mult;
1150 num_divs++;
1151 }
1152 last_size = (u64)last_ssize;
1153 } else {
1154 while (size >= mult) {
1155 last_size = size;
1156 size /= mult;
1157 num_divs++;
1158 }
1159 }
1160 /*
1161 * If the value is smaller than base, we didn't do any
1162 * division, in that case, base should be 1, not original
1163 * base, or the unit will be wrong
1164 */
1165 if (num_divs == 0)
1166 base = 1;
1167 }
1168
1169 if (num_divs >= ARRAY_SIZE(unit_suffix_binary)) {
1170 str[0] = '\0';
1171 printf("INTERNAL ERROR: unsupported unit suffix, index %d\n",
1172 num_divs);
1173 assert(0);
1174 return -1;
1175 }
1176
1177 if (negative) {
1178 fraction = (float)(s64)last_size / base;
1179 } else {
1180 fraction = (float)last_size / base;
1181 }
1182
1183 return snprintf(str, str_size, "%.2f%s", fraction, suffix[num_divs]);
1184 }
1185
1186 /*
1187 * __strncpy_null - strncpy with null termination
1188 * @dest: the target array
1189 * @src: the source string
1190 * @n: maximum bytes to copy (size of *dest)
1191 *
1192 * Like strncpy, but ensures destination is null-terminated.
1193 *
1194 * Copies the string pointed to by src, including the terminating null
1195 * byte ('\0'), to the buffer pointed to by dest, up to a maximum
1196 * of n bytes. Then ensure that dest is null-terminated.
1197 */
1198 char *__strncpy_null(char *dest, const char *src, size_t n)
1199 {
1200 strncpy(dest, src, n);
1201 if (n > 0)
1202 dest[n - 1] = '\0';
1203 return dest;
1204 }
1205
1206 /*
1207 * Checks to make sure that the label matches our requirements.
1208 * Returns:
1209 0 if everything is safe and usable
1210 -1 if the label is too long
1211 */
1212 static int check_label(const char *input)
1213 {
1214 int len = strlen(input);
1215
1216 if (len > BTRFS_LABEL_SIZE - 1) {
1217 error("label %s is too long (max %d)", input,
1218 BTRFS_LABEL_SIZE - 1);
1219 return -1;
1220 }
1221
1222 return 0;
1223 }
1224
1225 static int set_label_unmounted(const char *dev, const char *label)
1226 {
1227 struct btrfs_trans_handle *trans;
1228 struct btrfs_root *root;
1229 int ret;
1230
1231 ret = check_mounted(dev);
1232 if (ret < 0) {
1233 error("checking mount status of %s failed: %d", dev, ret);
1234 return -1;
1235 }
1236 if (ret > 0) {
1237 error("device %s is mounted, use mount point", dev);
1238 return -1;
1239 }
1240
1241 /* Open the super_block at the default location
1242 * and as read-write.
1243 */
1244 root = open_ctree(dev, 0, OPEN_CTREE_WRITES);
1245 if (!root) /* errors are printed by open_ctree() */
1246 return -1;
1247
1248 trans = btrfs_start_transaction(root, 1);
1249 BUG_ON(IS_ERR(trans));
1250 __strncpy_null(root->fs_info->super_copy->label, label, BTRFS_LABEL_SIZE - 1);
1251
1252 btrfs_commit_transaction(trans, root);
1253
1254 /* Now we close it since we are done. */
1255 close_ctree(root);
1256 return 0;
1257 }
1258
1259 static int set_label_mounted(const char *mount_path, const char *labelp)
1260 {
1261 int fd;
1262 char label[BTRFS_LABEL_SIZE];
1263
1264 fd = open(mount_path, O_RDONLY | O_NOATIME);
1265 if (fd < 0) {
1266 error("unable to access %s: %m", mount_path);
1267 return -1;
1268 }
1269
1270 memset(label, 0, sizeof(label));
1271 __strncpy_null(label, labelp, BTRFS_LABEL_SIZE - 1);
1272 if (ioctl(fd, BTRFS_IOC_SET_FSLABEL, label) < 0) {
1273 error("unable to set label of %s: %m", mount_path);
1274 close(fd);
1275 return -1;
1276 }
1277
1278 close(fd);
1279 return 0;
1280 }
1281
1282 int get_label_unmounted(const char *dev, char *label)
1283 {
1284 struct btrfs_root *root;
1285 int ret;
1286
1287 ret = check_mounted(dev);
1288 if (ret < 0) {
1289 error("checking mount status of %s failed: %d", dev, ret);
1290 return -1;
1291 }
1292
1293 /* Open the super_block at the default location
1294 * and as read-only.
1295 */
1296 root = open_ctree(dev, 0, 0);
1297 if(!root)
1298 return -1;
1299
1300 __strncpy_null(label, root->fs_info->super_copy->label,
1301 BTRFS_LABEL_SIZE - 1);
1302
1303 /* Now we close it since we are done. */
1304 close_ctree(root);
1305 return 0;
1306 }
1307
1308 /*
1309 * If a partition is mounted, try to get the filesystem label via its
1310 * mounted path rather than device. Return the corresponding error
1311 * the user specified the device path.
1312 */
1313 int get_label_mounted(const char *mount_path, char *labelp)
1314 {
1315 char label[BTRFS_LABEL_SIZE];
1316 int fd;
1317 int ret;
1318
1319 fd = open(mount_path, O_RDONLY | O_NOATIME);
1320 if (fd < 0) {
1321 error("unable to access %s: %m", mount_path);
1322 return -1;
1323 }
1324
1325 memset(label, '\0', sizeof(label));
1326 ret = ioctl(fd, BTRFS_IOC_GET_FSLABEL, label);
1327 if (ret < 0) {
1328 if (errno != ENOTTY)
1329 error("unable to get label of %s: %m", mount_path);
1330 ret = -errno;
1331 close(fd);
1332 return ret;
1333 }
1334
1335 __strncpy_null(labelp, label, BTRFS_LABEL_SIZE - 1);
1336 close(fd);
1337 return 0;
1338 }
1339
1340 int get_label(const char *btrfs_dev, char *label)
1341 {
1342 int ret;
1343
1344 ret = is_existing_blk_or_reg_file(btrfs_dev);
1345 if (!ret)
1346 ret = get_label_mounted(btrfs_dev, label);
1347 else if (ret > 0)
1348 ret = get_label_unmounted(btrfs_dev, label);
1349
1350 return ret;
1351 }
1352
1353 int set_label(const char *btrfs_dev, const char *label)
1354 {
1355 int ret;
1356
1357 if (check_label(label))
1358 return -1;
1359
1360 ret = is_existing_blk_or_reg_file(btrfs_dev);
1361 if (!ret)
1362 ret = set_label_mounted(btrfs_dev, label);
1363 else if (ret > 0)
1364 ret = set_label_unmounted(btrfs_dev, label);
1365
1366 return ret;
1367 }
1368
1369 /*
1370 * A not-so-good version fls64. No fascinating optimization since
1371 * no one except parse_size use it
1372 */
1373 static int fls64(u64 x)
1374 {
1375 int i;
1376
1377 for (i = 0; i <64; i++)
1378 if (x << i & (1ULL << 63))
1379 return 64 - i;
1380 return 64 - i;
1381 }
1382
1383 u64 parse_size(char *s)
1384 {
1385 char c;
1386 char *endptr;
1387 u64 mult = 1;
1388 u64 ret;
1389
1390 if (!s) {
1391 error("size value is empty");
1392 exit(1);
1393 }
1394 if (s[0] == '-') {
1395 error("size value '%s' is less equal than 0", s);
1396 exit(1);
1397 }
1398 ret = strtoull(s, &endptr, 10);
1399 if (endptr == s) {
1400 error("size value '%s' is invalid", s);
1401 exit(1);
1402 }
1403 if (endptr[0] && endptr[1]) {
1404 error("illegal suffix contains character '%c' in wrong position",
1405 endptr[1]);
1406 exit(1);
1407 }
1408 /*
1409 * strtoll returns LLONG_MAX when overflow, if this happens,
1410 * need to call strtoull to get the real size
1411 */
1412 if (errno == ERANGE && ret == ULLONG_MAX) {
1413 error("size value '%s' is too large for u64", s);
1414 exit(1);
1415 }
1416 if (endptr[0]) {
1417 c = tolower(endptr[0]);
1418 switch (c) {
1419 case 'e':
1420 mult *= 1024;
1421 /* fallthrough */
1422 case 'p':
1423 mult *= 1024;
1424 /* fallthrough */
1425 case 't':
1426 mult *= 1024;
1427 /* fallthrough */
1428 case 'g':
1429 mult *= 1024;
1430 /* fallthrough */
1431 case 'm':
1432 mult *= 1024;
1433 /* fallthrough */
1434 case 'k':
1435 mult *= 1024;
1436 /* fallthrough */
1437 case 'b':
1438 break;
1439 default:
1440 error("unknown size descriptor '%c'", c);
1441 exit(1);
1442 }
1443 }
1444 /* Check whether ret * mult overflow */
1445 if (fls64(ret) + fls64(mult) - 1 > 64) {
1446 error("size value '%s' is too large for u64", s);
1447 exit(1);
1448 }
1449 ret *= mult;
1450 return ret;
1451 }
1452
1453 u64 parse_qgroupid(const char *p)
1454 {
1455 char *s = strchr(p, '/');
1456 const char *ptr_src_end = p + strlen(p);
1457 char *ptr_parse_end = NULL;
1458 enum btrfs_util_error err;
1459 u64 level;
1460 u64 id;
1461 int fd;
1462 int ret = 0;
1463
1464 if (p[0] == '/')
1465 goto path;
1466
1467 /* Numeric format like '0/257' is the primary case */
1468 if (!s) {
1469 id = strtoull(p, &ptr_parse_end, 10);
1470 if (ptr_parse_end != ptr_src_end)
1471 goto path;
1472 return id;
1473 }
1474 level = strtoull(p, &ptr_parse_end, 10);
1475 if (ptr_parse_end != s)
1476 goto path;
1477
1478 id = strtoull(s + 1, &ptr_parse_end, 10);
1479 if (ptr_parse_end != ptr_src_end)
1480 goto path;
1481
1482 return (level << BTRFS_QGROUP_LEVEL_SHIFT) | id;
1483
1484 path:
1485 /* Path format like subv at 'my_subvol' is the fallback case */
1486 err = btrfs_util_is_subvolume(p);
1487 if (err)
1488 goto err;
1489 fd = open(p, O_RDONLY);
1490 if (fd < 0)
1491 goto err;
1492 ret = lookup_path_rootid(fd, &id);
1493 if (ret)
1494 error("failed to lookup root id: %s", strerror(-ret));
1495 close(fd);
1496 if (ret < 0)
1497 goto err;
1498 return id;
1499
1500 err:
1501 error("invalid qgroupid or subvolume path: %s", p);
1502 exit(-1);
1503 }
1504
1505 int open_file_or_dir3(const char *fname, DIR **dirstream, int open_flags)
1506 {
1507 int ret;
1508 struct stat st;
1509 int fd;
1510
1511 ret = stat(fname, &st);
1512 if (ret < 0) {
1513 return -1;
1514 }
1515 if (S_ISDIR(st.st_mode)) {
1516 *dirstream = opendir(fname);
1517 if (!*dirstream)
1518 return -1;
1519 fd = dirfd(*dirstream);
1520 } else if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)) {
1521 fd = open(fname, open_flags);
1522 } else {
1523 /*
1524 * we set this on purpose, in case the caller output
1525 * strerror(errno) as success
1526 */
1527 errno = EINVAL;
1528 return -1;
1529 }
1530 if (fd < 0) {
1531 fd = -1;
1532 if (*dirstream) {
1533 closedir(*dirstream);
1534 *dirstream = NULL;
1535 }
1536 }
1537 return fd;
1538 }
1539
1540 int open_file_or_dir(const char *fname, DIR **dirstream)
1541 {
1542 return open_file_or_dir3(fname, dirstream, O_RDWR);
1543 }
1544
1545 void close_file_or_dir(int fd, DIR *dirstream)
1546 {
1547 int old_errno;
1548
1549 old_errno = errno;
1550 if (dirstream) {
1551 closedir(dirstream);
1552 } else if (fd >= 0) {
1553 close(fd);
1554 }
1555
1556 errno = old_errno;
1557 }
1558
1559 int get_device_info(int fd, u64 devid,
1560 struct btrfs_ioctl_dev_info_args *di_args)
1561 {
1562 int ret;
1563
1564 di_args->devid = devid;
1565 memset(&di_args->uuid, '\0', sizeof(di_args->uuid));
1566
1567 ret = ioctl(fd, BTRFS_IOC_DEV_INFO, di_args);
1568 return ret < 0 ? -errno : 0;
1569 }
1570
1571 static u64 find_max_device_id(struct btrfs_ioctl_search_args *search_args,
1572 int nr_items)
1573 {
1574 struct btrfs_dev_item *dev_item;
1575 char *buf = search_args->buf;
1576
1577 buf += (nr_items - 1) * (sizeof(struct btrfs_ioctl_search_header)
1578 + sizeof(struct btrfs_dev_item));
1579 buf += sizeof(struct btrfs_ioctl_search_header);
1580
1581 dev_item = (struct btrfs_dev_item *)buf;
1582
1583 return btrfs_stack_device_id(dev_item);
1584 }
1585
1586 static int search_chunk_tree_for_fs_info(int fd,
1587 struct btrfs_ioctl_fs_info_args *fi_args)
1588 {
1589 int ret;
1590 int max_items;
1591 u64 start_devid = 1;
1592 struct btrfs_ioctl_search_args search_args;
1593 struct btrfs_ioctl_search_key *search_key = &search_args.key;
1594
1595 fi_args->num_devices = 0;
1596
1597 max_items = BTRFS_SEARCH_ARGS_BUFSIZE
1598 / (sizeof(struct btrfs_ioctl_search_header)
1599 + sizeof(struct btrfs_dev_item));
1600
1601 search_key->tree_id = BTRFS_CHUNK_TREE_OBJECTID;
1602 search_key->min_objectid = BTRFS_DEV_ITEMS_OBJECTID;
1603 search_key->max_objectid = BTRFS_DEV_ITEMS_OBJECTID;
1604 search_key->min_type = BTRFS_DEV_ITEM_KEY;
1605 search_key->max_type = BTRFS_DEV_ITEM_KEY;
1606 search_key->min_transid = 0;
1607 search_key->max_transid = (u64)-1;
1608 search_key->nr_items = max_items;
1609 search_key->max_offset = (u64)-1;
1610
1611 again:
1612 search_key->min_offset = start_devid;
1613
1614 ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &search_args);
1615 if (ret < 0)
1616 return -errno;
1617
1618 fi_args->num_devices += (u64)search_key->nr_items;
1619
1620 if (search_key->nr_items == max_items) {
1621 start_devid = find_max_device_id(&search_args,
1622 search_key->nr_items) + 1;
1623 goto again;
1624 }
1625
1626 /* get the lastest max_id to stay consistent with the num_devices */
1627 if (search_key->nr_items == 0)
1628 /*
1629 * last tree_search returns an empty buf, use the devid of
1630 * the last dev_item of the previous tree_search
1631 */
1632 fi_args->max_id = start_devid - 1;
1633 else
1634 fi_args->max_id = find_max_device_id(&search_args,
1635 search_key->nr_items);
1636
1637 return 0;
1638 }
1639
1640 /*
1641 * For a given path, fill in the ioctl fs_ and info_ args.
1642 * If the path is a btrfs mountpoint, fill info for all devices.
1643 * If the path is a btrfs device, fill in only that device.
1644 *
1645 * The path provided must be either on a mounted btrfs fs,
1646 * or be a mounted btrfs device.
1647 *
1648 * Returns 0 on success, or a negative errno.
1649 */
1650 int get_fs_info(const char *path, struct btrfs_ioctl_fs_info_args *fi_args,
1651 struct btrfs_ioctl_dev_info_args **di_ret)
1652 {
1653 int fd = -1;
1654 int ret = 0;
1655 int ndevs = 0;
1656 u64 last_devid = 0;
1657 int replacing = 0;
1658 struct btrfs_fs_devices *fs_devices_mnt = NULL;
1659 struct btrfs_ioctl_dev_info_args *di_args;
1660 struct btrfs_ioctl_dev_info_args tmp;
1661 char mp[PATH_MAX];
1662 DIR *dirstream = NULL;
1663
1664 memset(fi_args, 0, sizeof(*fi_args));
1665
1666 if (is_block_device(path) == 1) {
1667 struct btrfs_super_block *disk_super;
1668 char buf[BTRFS_SUPER_INFO_SIZE];
1669
1670 /* Ensure it's mounted, then set path to the mountpoint */
1671 fd = open(path, O_RDONLY);
1672 if (fd < 0) {
1673 ret = -errno;
1674 error("cannot open %s: %m", path);
1675 goto out;
1676 }
1677 ret = check_mounted_where(fd, path, mp, sizeof(mp),
1678 &fs_devices_mnt, SBREAD_DEFAULT);
1679 if (!ret) {
1680 ret = -EINVAL;
1681 goto out;
1682 }
1683 if (ret < 0)
1684 goto out;
1685 path = mp;
1686 /* Only fill in this one device */
1687 fi_args->num_devices = 1;
1688
1689 disk_super = (struct btrfs_super_block *)buf;
1690 ret = btrfs_read_dev_super(fd, disk_super,
1691 BTRFS_SUPER_INFO_OFFSET, 0);
1692 if (ret < 0) {
1693 ret = -EIO;
1694 goto out;
1695 }
1696 last_devid = btrfs_stack_device_id(&disk_super->dev_item);
1697 fi_args->max_id = last_devid;
1698
1699 memcpy(fi_args->fsid, fs_devices_mnt->fsid, BTRFS_FSID_SIZE);
1700 close(fd);
1701 }
1702
1703 /* at this point path must not be for a block device */
1704 fd = open_file_or_dir(path, &dirstream);
1705 if (fd < 0) {
1706 ret = -errno;
1707 goto out;
1708 }
1709
1710 /* fill in fi_args if not just a single device */
1711 if (fi_args->num_devices != 1) {
1712 ret = ioctl(fd, BTRFS_IOC_FS_INFO, fi_args);
1713 if (ret < 0) {
1714 ret = -errno;
1715 goto out;
1716 }
1717
1718 /*
1719 * The fs_args->num_devices does not include seed devices
1720 */
1721 ret = search_chunk_tree_for_fs_info(fd, fi_args);
1722 if (ret)
1723 goto out;
1724
1725 /*
1726 * search_chunk_tree_for_fs_info() will lacks the devid 0
1727 * so manual probe for it here.
1728 */
1729 ret = get_device_info(fd, 0, &tmp);
1730 if (!ret) {
1731 fi_args->num_devices++;
1732 ndevs++;
1733 replacing = 1;
1734 if (last_devid == 0)
1735 last_devid++;
1736 }
1737 }
1738
1739 if (!fi_args->num_devices)
1740 goto out;
1741
1742 di_args = *di_ret = malloc((fi_args->num_devices) * sizeof(*di_args));
1743 if (!di_args) {
1744 ret = -errno;
1745 goto out;
1746 }
1747
1748 if (replacing)
1749 memcpy(di_args, &tmp, sizeof(tmp));
1750 for (; last_devid <= fi_args->max_id; last_devid++) {
1751 ret = get_device_info(fd, last_devid, &di_args[ndevs]);
1752 if (ret == -ENODEV)
1753 continue;
1754 if (ret)
1755 goto out;
1756 ndevs++;
1757 }
1758
1759 /*
1760 * only when the only dev we wanted to find is not there then
1761 * let any error be returned
1762 */
1763 if (fi_args->num_devices != 1) {
1764 BUG_ON(ndevs == 0);
1765 ret = 0;
1766 }
1767
1768 out:
1769 close_file_or_dir(fd, dirstream);
1770 return ret;
1771 }
1772
1773 int get_fsid(const char *path, u8 *fsid, int silent)
1774 {
1775 int ret;
1776 int fd;
1777 struct btrfs_ioctl_fs_info_args args;
1778
1779 fd = open(path, O_RDONLY);
1780 if (fd < 0) {
1781 ret = -errno;
1782 if (!silent)
1783 error("failed to open %s: %s", path,
1784 strerror(-ret));
1785 goto out;
1786 }
1787
1788 ret = ioctl(fd, BTRFS_IOC_FS_INFO, &args);
1789 if (ret < 0) {
1790 ret = -errno;
1791 goto out;
1792 }
1793
1794 memcpy(fsid, args.fsid, BTRFS_FSID_SIZE);
1795 ret = 0;
1796
1797 out:
1798 if (fd != -1)
1799 close(fd);
1800 return ret;
1801 }
1802
1803 int is_seen_fsid(u8 *fsid, struct seen_fsid *seen_fsid_hash[])
1804 {
1805 u8 hash = fsid[0];
1806 int slot = hash % SEEN_FSID_HASH_SIZE;
1807 struct seen_fsid *seen = seen_fsid_hash[slot];
1808
1809 while (seen) {
1810 if (memcmp(seen->fsid, fsid, BTRFS_FSID_SIZE) == 0)
1811 return 1;
1812
1813 seen = seen->next;
1814 }
1815
1816 return 0;
1817 }
1818
1819 int add_seen_fsid(u8 *fsid, struct seen_fsid *seen_fsid_hash[],
1820 int fd, DIR *dirstream)
1821 {
1822 u8 hash = fsid[0];
1823 int slot = hash % SEEN_FSID_HASH_SIZE;
1824 struct seen_fsid *seen = seen_fsid_hash[slot];
1825 struct seen_fsid *alloc;
1826
1827 if (!seen)
1828 goto insert;
1829
1830 while (1) {
1831 if (memcmp(seen->fsid, fsid, BTRFS_FSID_SIZE) == 0)
1832 return -EEXIST;
1833
1834 if (!seen->next)
1835 break;
1836
1837 seen = seen->next;
1838 }
1839
1840 insert:
1841 alloc = malloc(sizeof(*alloc));
1842 if (!alloc)
1843 return -ENOMEM;
1844
1845 alloc->next = NULL;
1846 memcpy(alloc->fsid, fsid, BTRFS_FSID_SIZE);
1847 alloc->fd = fd;
1848 alloc->dirstream = dirstream;
1849
1850 if (seen)
1851 seen->next = alloc;
1852 else
1853 seen_fsid_hash[slot] = alloc;
1854
1855 return 0;
1856 }
1857
1858 void free_seen_fsid(struct seen_fsid *seen_fsid_hash[])
1859 {
1860 int slot;
1861 struct seen_fsid *seen;
1862 struct seen_fsid *next;
1863
1864 for (slot = 0; slot < SEEN_FSID_HASH_SIZE; slot++) {
1865 seen = seen_fsid_hash[slot];
1866 while (seen) {
1867 next = seen->next;
1868 close_file_or_dir(seen->fd, seen->dirstream);
1869 free(seen);
1870 seen = next;
1871 }
1872 seen_fsid_hash[slot] = NULL;
1873 }
1874 }
1875
1876 static int group_profile_devs_min(u64 flag)
1877 {
1878 switch (flag & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
1879 case 0: /* single */
1880 case BTRFS_BLOCK_GROUP_DUP:
1881 return 1;
1882 case BTRFS_BLOCK_GROUP_RAID0:
1883 case BTRFS_BLOCK_GROUP_RAID1:
1884 case BTRFS_BLOCK_GROUP_RAID5:
1885 return 2;
1886 case BTRFS_BLOCK_GROUP_RAID6:
1887 return 3;
1888 case BTRFS_BLOCK_GROUP_RAID10:
1889 return 4;
1890 default:
1891 return -1;
1892 }
1893 }
1894
1895 int test_num_disk_vs_raid(u64 metadata_profile, u64 data_profile,
1896 u64 dev_cnt, int mixed, int ssd)
1897 {
1898 u64 allowed = 0;
1899 u64 profile = metadata_profile | data_profile;
1900
1901 switch (dev_cnt) {
1902 default:
1903 case 4:
1904 allowed |= BTRFS_BLOCK_GROUP_RAID10;
1905 case 3:
1906 allowed |= BTRFS_BLOCK_GROUP_RAID6;
1907 case 2:
1908 allowed |= BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
1909 BTRFS_BLOCK_GROUP_RAID5;
1910 case 1:
1911 allowed |= BTRFS_BLOCK_GROUP_DUP;
1912 }
1913
1914 if (dev_cnt > 1 && profile & BTRFS_BLOCK_GROUP_DUP) {
1915 warning("DUP is not recommended on filesystem with multiple devices");
1916 }
1917 if (metadata_profile & ~allowed) {
1918 fprintf(stderr,
1919 "ERROR: unable to create FS with metadata profile %s "
1920 "(have %llu devices but %d devices are required)\n",
1921 btrfs_group_profile_str(metadata_profile), dev_cnt,
1922 group_profile_devs_min(metadata_profile));
1923 return 1;
1924 }
1925 if (data_profile & ~allowed) {
1926 fprintf(stderr,
1927 "ERROR: unable to create FS with data profile %s "
1928 "(have %llu devices but %d devices are required)\n",
1929 btrfs_group_profile_str(data_profile), dev_cnt,
1930 group_profile_devs_min(data_profile));
1931 return 1;
1932 }
1933
1934 if (dev_cnt == 3 && profile & BTRFS_BLOCK_GROUP_RAID6) {
1935 warning("RAID6 is not recommended on filesystem with 3 devices only");
1936 }
1937 if (dev_cnt == 2 && profile & BTRFS_BLOCK_GROUP_RAID5) {
1938 warning("RAID5 is not recommended on filesystem with 2 devices only");
1939 }
1940 warning_on(!mixed && (data_profile & BTRFS_BLOCK_GROUP_DUP) && ssd,
1941 "DUP may not actually lead to 2 copies on the device, see manual page");
1942
1943 return 0;
1944 }
1945
1946 int group_profile_max_safe_loss(u64 flags)
1947 {
1948 switch (flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
1949 case 0: /* single */
1950 case BTRFS_BLOCK_GROUP_DUP:
1951 case BTRFS_BLOCK_GROUP_RAID0:
1952 return 0;
1953 case BTRFS_BLOCK_GROUP_RAID1:
1954 case BTRFS_BLOCK_GROUP_RAID5:
1955 case BTRFS_BLOCK_GROUP_RAID10:
1956 return 1;
1957 case BTRFS_BLOCK_GROUP_RAID6:
1958 return 2;
1959 default:
1960 return -1;
1961 }
1962 }
1963
1964 int btrfs_scan_devices(void)
1965 {
1966 int fd = -1;
1967 int ret;
1968 u64 num_devices;
1969 struct btrfs_fs_devices *tmp_devices;
1970 blkid_dev_iterate iter = NULL;
1971 blkid_dev dev = NULL;
1972 blkid_cache cache = NULL;
1973 char path[PATH_MAX];
1974
1975 if (btrfs_scan_done)
1976 return 0;
1977
1978 if (blkid_get_cache(&cache, NULL) < 0) {
1979 error("blkid cache get failed");
1980 return 1;
1981 }
1982 blkid_probe_all(cache);
1983 iter = blkid_dev_iterate_begin(cache);
1984 blkid_dev_set_search(iter, "TYPE", "btrfs");
1985 while (blkid_dev_next(iter, &dev) == 0) {
1986 dev = blkid_verify(cache, dev);
1987 if (!dev)
1988 continue;
1989 /* if we are here its definitely a btrfs disk*/
1990 strncpy_null(path, blkid_dev_devname(dev));
1991
1992 fd = open(path, O_RDONLY);
1993 if (fd < 0) {
1994 error("cannot open %s: %m", path);
1995 continue;
1996 }
1997 ret = btrfs_scan_one_device(fd, path, &tmp_devices,
1998 &num_devices, BTRFS_SUPER_INFO_OFFSET,
1999 SBREAD_DEFAULT);
2000 if (ret) {
2001 error("cannot scan %s: %s", path, strerror(-ret));
2002 close (fd);
2003 continue;
2004 }
2005
2006 close(fd);
2007 }
2008 blkid_dev_iterate_end(iter);
2009 blkid_put_cache(cache);
2010
2011 btrfs_scan_done = 1;
2012
2013 return 0;
2014 }
2015
2016 /*
2017 * This reads a line from the stdin and only returns non-zero if the
2018 * first whitespace delimited token is a case insensitive match with yes
2019 * or y.
2020 */
2021 int ask_user(const char *question)
2022 {
2023 char buf[30] = {0,};
2024 char *saveptr = NULL;
2025 char *answer;
2026
2027 printf("%s [y/N]: ", question);
2028
2029 return fgets(buf, sizeof(buf) - 1, stdin) &&
2030 (answer = strtok_r(buf, " \t\n\r", &saveptr)) &&
2031 (!strcasecmp(answer, "yes") || !strcasecmp(answer, "y"));
2032 }
2033
2034 /*
2035 * return 0 if a btrfs mount point is found
2036 * return 1 if a mount point is found but not btrfs
2037 * return <0 if something goes wrong
2038 */
2039 int find_mount_root(const char *path, char **mount_root)
2040 {
2041 FILE *mnttab;
2042 int fd;
2043 struct mntent *ent;
2044 int len;
2045 int ret;
2046 int not_btrfs = 1;
2047 int longest_matchlen = 0;
2048 char *longest_match = NULL;
2049
2050 fd = open(path, O_RDONLY | O_NOATIME);
2051 if (fd < 0)
2052 return -errno;
2053 close(fd);
2054
2055 mnttab = setmntent("/proc/self/mounts", "r");
2056 if (!mnttab)
2057 return -errno;
2058
2059 while ((ent = getmntent(mnttab))) {
2060 len = strlen(ent->mnt_dir);
2061 if (strncmp(ent->mnt_dir, path, len) == 0) {
2062 /* match found and use the latest match */
2063 if (longest_matchlen <= len) {
2064 free(longest_match);
2065 longest_matchlen = len;
2066 longest_match = strdup(ent->mnt_dir);
2067 not_btrfs = strcmp(ent->mnt_type, "btrfs");
2068 }
2069 }
2070 }
2071 endmntent(mnttab);
2072
2073 if (!longest_match)
2074 return -ENOENT;
2075 if (not_btrfs) {
2076 free(longest_match);
2077 return 1;
2078 }
2079
2080 ret = 0;
2081 *mount_root = realpath(longest_match, NULL);
2082 if (!*mount_root)
2083 ret = -errno;
2084
2085 free(longest_match);
2086 return ret;
2087 }
2088
2089 /*
2090 * Test if path is a directory
2091 * Returns:
2092 * 0 - path exists but it is not a directory
2093 * 1 - path exists and it is a directory
2094 * < 0 - error
2095 */
2096 int test_isdir(const char *path)
2097 {
2098 struct stat st;
2099 int ret;
2100
2101 ret = stat(path, &st);
2102 if (ret < 0)
2103 return -errno;
2104
2105 return !!S_ISDIR(st.st_mode);
2106 }
2107
2108 void units_set_mode(unsigned *units, unsigned mode)
2109 {
2110 unsigned base = *units & UNITS_MODE_MASK;
2111
2112 *units = base | mode;
2113 }
2114
2115 void units_set_base(unsigned *units, unsigned base)
2116 {
2117 unsigned mode = *units & ~UNITS_MODE_MASK;
2118
2119 *units = base | mode;
2120 }
2121
2122 int find_next_key(struct btrfs_path *path, struct btrfs_key *key)
2123 {
2124 int level;
2125
2126 for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
2127 if (!path->nodes[level])
2128 break;
2129 if (path->slots[level] + 1 >=
2130 btrfs_header_nritems(path->nodes[level]))
2131 continue;
2132 if (level == 0)
2133 btrfs_item_key_to_cpu(path->nodes[level], key,
2134 path->slots[level] + 1);
2135 else
2136 btrfs_node_key_to_cpu(path->nodes[level], key,
2137 path->slots[level] + 1);
2138 return 0;
2139 }
2140 return 1;
2141 }
2142
2143 const char* btrfs_group_type_str(u64 flag)
2144 {
2145 u64 mask = BTRFS_BLOCK_GROUP_TYPE_MASK |
2146 BTRFS_SPACE_INFO_GLOBAL_RSV;
2147
2148 switch (flag & mask) {
2149 case BTRFS_BLOCK_GROUP_DATA:
2150 return "Data";
2151 case BTRFS_BLOCK_GROUP_SYSTEM:
2152 return "System";
2153 case BTRFS_BLOCK_GROUP_METADATA:
2154 return "Metadata";
2155 case BTRFS_BLOCK_GROUP_DATA|BTRFS_BLOCK_GROUP_METADATA:
2156 return "Data+Metadata";
2157 case BTRFS_SPACE_INFO_GLOBAL_RSV:
2158 return "GlobalReserve";
2159 default:
2160 return "unknown";
2161 }
2162 }
2163
2164 const char* btrfs_group_profile_str(u64 flag)
2165 {
2166 switch (flag & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
2167 case 0:
2168 return "single";
2169 case BTRFS_BLOCK_GROUP_RAID0:
2170 return "RAID0";
2171 case BTRFS_BLOCK_GROUP_RAID1:
2172 return "RAID1";
2173 case BTRFS_BLOCK_GROUP_RAID5:
2174 return "RAID5";
2175 case BTRFS_BLOCK_GROUP_RAID6:
2176 return "RAID6";
2177 case BTRFS_BLOCK_GROUP_DUP:
2178 return "DUP";
2179 case BTRFS_BLOCK_GROUP_RAID10:
2180 return "RAID10";
2181 default:
2182 return "unknown";
2183 }
2184 }
2185
2186 u64 disk_size(const char *path)
2187 {
2188 struct statfs sfs;
2189
2190 if (statfs(path, &sfs) < 0)
2191 return 0;
2192 else
2193 return sfs.f_bsize * sfs.f_blocks;
2194 }
2195
2196 u64 get_partition_size(const char *dev)
2197 {
2198 u64 result;
2199 int fd = open(dev, O_RDONLY);
2200
2201 if (fd < 0)
2202 return 0;
2203 if (ioctl(fd, BLKGETSIZE64, &result) < 0) {
2204 close(fd);
2205 return 0;
2206 }
2207 close(fd);
2208
2209 return result;
2210 }
2211
2212 /*
2213 * Check if the BTRFS_IOC_TREE_SEARCH_V2 ioctl is supported on a given
2214 * filesystem, opened at fd
2215 */
2216 int btrfs_tree_search2_ioctl_supported(int fd)
2217 {
2218 struct btrfs_ioctl_search_args_v2 *args2;
2219 struct btrfs_ioctl_search_key *sk;
2220 int args2_size = 1024;
2221 char args2_buf[args2_size];
2222 int ret;
2223
2224 args2 = (struct btrfs_ioctl_search_args_v2 *)args2_buf;
2225 sk = &(args2->key);
2226
2227 /*
2228 * Search for the extent tree item in the root tree.
2229 */
2230 sk->tree_id = BTRFS_ROOT_TREE_OBJECTID;
2231 sk->min_objectid = BTRFS_EXTENT_TREE_OBJECTID;
2232 sk->max_objectid = BTRFS_EXTENT_TREE_OBJECTID;
2233 sk->min_type = BTRFS_ROOT_ITEM_KEY;
2234 sk->max_type = BTRFS_ROOT_ITEM_KEY;
2235 sk->min_offset = 0;
2236 sk->max_offset = (u64)-1;
2237 sk->min_transid = 0;
2238 sk->max_transid = (u64)-1;
2239 sk->nr_items = 1;
2240 args2->buf_size = args2_size - sizeof(struct btrfs_ioctl_search_args_v2);
2241 ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH_V2, args2);
2242 if (ret == -EOPNOTSUPP)
2243 return 0;
2244 else if (ret == 0)
2245 return 1;
2246 return ret;
2247 }
2248
2249 int btrfs_check_nodesize(u32 nodesize, u32 sectorsize, u64 features)
2250 {
2251 if (nodesize < sectorsize) {
2252 error("illegal nodesize %u (smaller than %u)",
2253 nodesize, sectorsize);
2254 return -1;
2255 } else if (nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2256 error("illegal nodesize %u (larger than %u)",
2257 nodesize, BTRFS_MAX_METADATA_BLOCKSIZE);
2258 return -1;
2259 } else if (nodesize & (sectorsize - 1)) {
2260 error("illegal nodesize %u (not aligned to %u)",
2261 nodesize, sectorsize);
2262 return -1;
2263 } else if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS &&
2264 nodesize != sectorsize) {
2265 error("illegal nodesize %u (not equal to %u for mixed block group)",
2266 nodesize, sectorsize);
2267 return -1;
2268 }
2269 return 0;
2270 }
2271
2272 /*
2273 * Copy a path argument from SRC to DEST and check the SRC length if it's at
2274 * most PATH_MAX and fits into DEST. DESTLEN is supposed to be exact size of
2275 * the buffer.
2276 * The destination buffer is zero terminated.
2277 * Return < 0 for error, 0 otherwise.
2278 */
2279 int arg_copy_path(char *dest, const char *src, int destlen)
2280 {
2281 size_t len = strlen(src);
2282
2283 if (len >= PATH_MAX || len >= destlen)
2284 return -ENAMETOOLONG;
2285
2286 __strncpy_null(dest, src, destlen);
2287
2288 return 0;
2289 }
2290
2291 unsigned int get_unit_mode_from_arg(int *argc, char *argv[], int df_mode)
2292 {
2293 unsigned int unit_mode = UNITS_DEFAULT;
2294 int arg_i;
2295 int arg_end;
2296
2297 for (arg_i = 0; arg_i < *argc; arg_i++) {
2298 if (!strcmp(argv[arg_i], "--"))
2299 break;
2300
2301 if (!strcmp(argv[arg_i], "--raw")) {
2302 unit_mode = UNITS_RAW;
2303 argv[arg_i] = NULL;
2304 continue;
2305 }
2306 if (!strcmp(argv[arg_i], "--human-readable")) {
2307 unit_mode = UNITS_HUMAN_BINARY;
2308 argv[arg_i] = NULL;
2309 continue;
2310 }
2311
2312 if (!strcmp(argv[arg_i], "--iec")) {
2313 units_set_mode(&unit_mode, UNITS_BINARY);
2314 argv[arg_i] = NULL;
2315 continue;
2316 }
2317 if (!strcmp(argv[arg_i], "--si")) {
2318 units_set_mode(&unit_mode, UNITS_DECIMAL);
2319 argv[arg_i] = NULL;
2320 continue;
2321 }
2322
2323 if (!strcmp(argv[arg_i], "--kbytes")) {
2324 units_set_base(&unit_mode, UNITS_KBYTES);
2325 argv[arg_i] = NULL;
2326 continue;
2327 }
2328 if (!strcmp(argv[arg_i], "--mbytes")) {
2329 units_set_base(&unit_mode, UNITS_MBYTES);
2330 argv[arg_i] = NULL;
2331 continue;
2332 }
2333 if (!strcmp(argv[arg_i], "--gbytes")) {
2334 units_set_base(&unit_mode, UNITS_GBYTES);
2335 argv[arg_i] = NULL;
2336 continue;
2337 }
2338 if (!strcmp(argv[arg_i], "--tbytes")) {
2339 units_set_base(&unit_mode, UNITS_TBYTES);
2340 argv[arg_i] = NULL;
2341 continue;
2342 }
2343
2344 if (!df_mode)
2345 continue;
2346
2347 if (!strcmp(argv[arg_i], "-b")) {
2348 unit_mode = UNITS_RAW;
2349 argv[arg_i] = NULL;
2350 continue;
2351 }
2352 if (!strcmp(argv[arg_i], "-h")) {
2353 unit_mode = UNITS_HUMAN_BINARY;
2354 argv[arg_i] = NULL;
2355 continue;
2356 }
2357 if (!strcmp(argv[arg_i], "-H")) {
2358 unit_mode = UNITS_HUMAN_DECIMAL;
2359 argv[arg_i] = NULL;
2360 continue;
2361 }
2362 if (!strcmp(argv[arg_i], "-k")) {
2363 units_set_base(&unit_mode, UNITS_KBYTES);
2364 argv[arg_i] = NULL;
2365 continue;
2366 }
2367 if (!strcmp(argv[arg_i], "-m")) {
2368 units_set_base(&unit_mode, UNITS_MBYTES);
2369 argv[arg_i] = NULL;
2370 continue;
2371 }
2372 if (!strcmp(argv[arg_i], "-g")) {
2373 units_set_base(&unit_mode, UNITS_GBYTES);
2374 argv[arg_i] = NULL;
2375 continue;
2376 }
2377 if (!strcmp(argv[arg_i], "-t")) {
2378 units_set_base(&unit_mode, UNITS_TBYTES);
2379 argv[arg_i] = NULL;
2380 continue;
2381 }
2382 }
2383
2384 for (arg_i = 0, arg_end = 0; arg_i < *argc; arg_i++) {
2385 if (!argv[arg_i])
2386 continue;
2387 argv[arg_end] = argv[arg_i];
2388 arg_end++;
2389 }
2390
2391 *argc = arg_end;
2392
2393 return unit_mode;
2394 }
2395
2396 u64 div_factor(u64 num, int factor)
2397 {
2398 if (factor == 10)
2399 return num;
2400 num *= factor;
2401 num /= 10;
2402 return num;
2403 }
2404 /*
2405 * Get the length of the string converted from a u64 number.
2406 *
2407 * Result is equal to log10(num) + 1, but without the use of math library.
2408 */
2409 int count_digits(u64 num)
2410 {
2411 int ret = 0;
2412
2413 if (num == 0)
2414 return 1;
2415 while (num > 0) {
2416 ret++;
2417 num /= 10;
2418 }
2419 return ret;
2420 }
2421
2422 int string_is_numerical(const char *str)
2423 {
2424 if (!str)
2425 return 0;
2426 if (!(*str >= '0' && *str <= '9'))
2427 return 0;
2428 while (*str >= '0' && *str <= '9')
2429 str++;
2430 if (*str != '\0')
2431 return 0;
2432 return 1;
2433 }
2434
2435 int prefixcmp(const char *str, const char *prefix)
2436 {
2437 for (; ; str++, prefix++)
2438 if (!*prefix)
2439 return 0;
2440 else if (*str != *prefix)
2441 return (unsigned char)*prefix - (unsigned char)*str;
2442 }
2443
2444 /* Subvolume helper functions */
2445 /*
2446 * test if name is a correct subvolume name
2447 * this function return
2448 * 0-> name is not a correct subvolume name
2449 * 1-> name is a correct subvolume name
2450 */
2451 int test_issubvolname(const char *name)
2452 {
2453 return name[0] != '\0' && !strchr(name, '/') &&
2454 strcmp(name, ".") && strcmp(name, "..");
2455 }
2456
2457 const char *subvol_strip_mountpoint(const char *mnt, const char *full_path)
2458 {
2459 int len = strlen(mnt);
2460 if (!len)
2461 return full_path;
2462
2463 if ((strncmp(mnt, full_path, len) != 0) || ((len > 1) && (full_path[len] != '/'))) {
2464 error("not on mount point: %s", mnt);
2465 exit(1);
2466 }
2467
2468 if (mnt[len - 1] != '/')
2469 len += 1;
2470
2471 return full_path + len;
2472 }
2473
2474 /* Set the seed manually */
2475 void init_rand_seed(u64 seed)
2476 {
2477 int i;
2478
2479 /* only use the last 48 bits */
2480 for (i = 0; i < 3; i++) {
2481 rand_seed[i] = (unsigned short)(seed ^ (unsigned short)(-1));
2482 seed >>= 16;
2483 }
2484 rand_seed_initlized = 1;
2485 }
2486
2487 static void __init_seed(void)
2488 {
2489 struct timeval tv;
2490 int ret;
2491 int fd;
2492
2493 if(rand_seed_initlized)
2494 return;
2495 /* Use urandom as primary seed source. */
2496 fd = open("/dev/urandom", O_RDONLY);
2497 if (fd >= 0) {
2498 ret = read(fd, rand_seed, sizeof(rand_seed));
2499 close(fd);
2500 if (ret < sizeof(rand_seed))
2501 goto fallback;
2502 } else {
2503 fallback:
2504 /* Use time and pid as fallback seed */
2505 warning("failed to read /dev/urandom, use time and pid as random seed");
2506 gettimeofday(&tv, 0);
2507 rand_seed[0] = getpid() ^ (tv.tv_sec & 0xFFFF);
2508 rand_seed[1] = getppid() ^ (tv.tv_usec & 0xFFFF);
2509 rand_seed[2] = (tv.tv_sec ^ tv.tv_usec) >> 16;
2510 }
2511 rand_seed_initlized = 1;
2512 }
2513
2514 u32 rand_u32(void)
2515 {
2516 __init_seed();
2517 /*
2518 * Don't use nrand48, its range is [0,2^31) The highest bit will alwasy
2519 * be 0. Use jrand48 to include the highest bit.
2520 */
2521 return (u32)jrand48(rand_seed);
2522 }
2523
2524 /* Return random number in range [0, upper) */
2525 unsigned int rand_range(unsigned int upper)
2526 {
2527 __init_seed();
2528 /*
2529 * Use the full 48bits to mod, which would be more uniformly
2530 * distributed
2531 */
2532 return (unsigned int)(jrand48(rand_seed) % upper);
2533 }
2534
2535 int rand_int(void)
2536 {
2537 return (int)(rand_u32());
2538 }
2539
2540 u64 rand_u64(void)
2541 {
2542 u64 ret = 0;
2543
2544 ret += rand_u32();
2545 ret <<= 32;
2546 ret += rand_u32();
2547 return ret;
2548 }
2549
2550 u16 rand_u16(void)
2551 {
2552 return (u16)(rand_u32());
2553 }
2554
2555 u8 rand_u8(void)
2556 {
2557 return (u8)(rand_u32());
2558 }
2559
2560 void btrfs_config_init(void)
2561 {
2562 }
2563
2564 /* Returns total size of main memory in bytes, -1UL if error. */
2565 unsigned long total_memory(void)
2566 {
2567 struct sysinfo si;
2568
2569 if (sysinfo(&si) < 0) {
2570 error("can't determine memory size");
2571 return -1UL;
2572 }
2573 return si.totalram * si.mem_unit; /* bytes */
2574 }
2575
2576 void print_device_info(struct btrfs_device *device, char *prefix)
2577 {
2578 if (prefix)
2579 printf("%s", prefix);
2580 printf("Device: id = %llu, name = %s\n",
2581 device->devid, device->name);
2582 }
2583
2584 void print_all_devices(struct list_head *devices)
2585 {
2586 struct btrfs_device *dev;
2587
2588 printf("All Devices:\n");
2589 list_for_each_entry(dev, devices, dev_list)
2590 print_device_info(dev, "\t");
2591 printf("\n");
2592 }
(deprecated) Btrfs progs developments and patch integration