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btrfs-progs: mkfs: Prevent temporary system chunk to use space in reserved 1M range
[btrfs-progs-unstable/devel.git] / utils.c
blob4a16413cc282c71d84f933ad033d44399003f3c0
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 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 int is_path_exist(const char *path)
460 {
461 struct stat statbuf;
462 int ret;
463
464 ret = stat(path, &statbuf);
465 if (ret < 0) {
466 if (errno == ENOENT)
467 return 0;
468 else
469 return -errno;
470 }
471 return 1;
472 }
473
474 /*
475 * This function checks if the given input parameter is
476 * an uuid or a path
477 * return <0 : some error in the given input
478 * return BTRFS_ARG_UNKNOWN: unknown input
479 * return BTRFS_ARG_UUID: given input is uuid
480 * return BTRFS_ARG_MNTPOINT: given input is path
481 * return BTRFS_ARG_REG: given input is regular file
482 * return BTRFS_ARG_BLKDEV: given input is block device
483 */
484 int check_arg_type(const char *input)
485 {
486 uuid_t uuid;
487 char path[PATH_MAX];
488
489 if (!input)
490 return -EINVAL;
491
492 if (realpath(input, path)) {
493 if (is_block_device(path) == 1)
494 return BTRFS_ARG_BLKDEV;
495
496 if (is_mount_point(path) == 1)
497 return BTRFS_ARG_MNTPOINT;
498
499 if (is_reg_file(path))
500 return BTRFS_ARG_REG;
501
502 return BTRFS_ARG_UNKNOWN;
503 }
504
505 if (strlen(input) == (BTRFS_UUID_UNPARSED_SIZE - 1) &&
506 !uuid_parse(input, uuid))
507 return BTRFS_ARG_UUID;
508
509 return BTRFS_ARG_UNKNOWN;
510 }
511
512 /*
513 * Find the mount point for a mounted device.
514 * On success, returns 0 with mountpoint in *mp.
515 * On failure, returns -errno (not mounted yields -EINVAL)
516 * Is noisy on failures, expects to be given a mounted device.
517 */
518 int get_btrfs_mount(const char *dev, char *mp, size_t mp_size)
519 {
520 int ret;
521 int fd = -1;
522
523 ret = is_block_device(dev);
524 if (ret <= 0) {
525 if (!ret) {
526 error("not a block device: %s", dev);
527 ret = -EINVAL;
528 } else {
529 error("cannot check %s: %s", dev, strerror(-ret));
530 }
531 goto out;
532 }
533
534 fd = open(dev, O_RDONLY);
535 if (fd < 0) {
536 ret = -errno;
537 error("cannot open %s: %s", dev, strerror(errno));
538 goto out;
539 }
540
541 ret = check_mounted_where(fd, dev, mp, mp_size, NULL);
542 if (!ret) {
543 ret = -EINVAL;
544 } else { /* mounted, all good */
545 ret = 0;
546 }
547 out:
548 if (fd != -1)
549 close(fd);
550 return ret;
551 }
552
553 /*
554 * Given a pathname, return a filehandle to:
555 * the original pathname or,
556 * if the pathname is a mounted btrfs device, to its mountpoint.
557 *
558 * On error, return -1, errno should be set.
559 */
560 int open_path_or_dev_mnt(const char *path, DIR **dirstream, int verbose)
561 {
562 char mp[PATH_MAX];
563 int ret;
564
565 if (is_block_device(path)) {
566 ret = get_btrfs_mount(path, mp, sizeof(mp));
567 if (ret < 0) {
568 /* not a mounted btrfs dev */
569 error_on(verbose, "'%s' is not a mounted btrfs device",
570 path);
571 errno = EINVAL;
572 return -1;
573 }
574 ret = open_file_or_dir(mp, dirstream);
575 error_on(verbose && ret < 0, "can't access '%s': %s",
576 path, strerror(errno));
577 } else {
578 ret = btrfs_open_dir(path, dirstream, 1);
579 }
580
581 return ret;
582 }
583
584 /*
585 * Do the following checks before calling open_file_or_dir():
586 * 1: path is in a btrfs filesystem
587 * 2: path is a directory if dir_only is 1
588 */
589 int btrfs_open(const char *path, DIR **dirstream, int verbose, int dir_only)
590 {
591 struct statfs stfs;
592 struct stat st;
593 int ret;
594
595 if (statfs(path, &stfs) != 0) {
596 error_on(verbose, "cannot access '%s': %s", path,
597 strerror(errno));
598 return -1;
599 }
600
601 if (stfs.f_type != BTRFS_SUPER_MAGIC) {
602 error_on(verbose, "not a btrfs filesystem: %s", path);
603 return -2;
604 }
605
606 if (stat(path, &st) != 0) {
607 error_on(verbose, "cannot access '%s': %s", path,
608 strerror(errno));
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': %s", path,
620 strerror(errno));
621 }
622
623 return ret;
624 }
625
626 int btrfs_open_dir(const char *path, DIR **dirstream, int verbose)
627 {
628 return btrfs_open(path, dirstream, verbose, 1);
629 }
630
631 int btrfs_open_file_or_dir(const char *path, DIR **dirstream, int verbose)
632 {
633 return btrfs_open(path, dirstream, verbose, 0);
634 }
635
636 /* checks if a device is a loop device */
637 static int is_loop_device (const char* device) {
638 struct stat statbuf;
639
640 if(stat(device, &statbuf) < 0)
641 return -errno;
642
643 return (S_ISBLK(statbuf.st_mode) &&
644 MAJOR(statbuf.st_rdev) == LOOP_MAJOR);
645 }
646
647 /*
648 * Takes a loop device path (e.g. /dev/loop0) and returns
649 * the associated file (e.g. /images/my_btrfs.img) using
650 * loopdev API
651 */
652 static int resolve_loop_device_with_loopdev(const char* loop_dev, char* loop_file)
653 {
654 int fd;
655 int ret;
656 struct loop_info64 lo64;
657
658 fd = open(loop_dev, O_RDONLY | O_NONBLOCK);
659 if (fd < 0)
660 return -errno;
661 ret = ioctl(fd, LOOP_GET_STATUS64, &lo64);
662 if (ret < 0) {
663 ret = -errno;
664 goto out;
665 }
666
667 memcpy(loop_file, lo64.lo_file_name, sizeof(lo64.lo_file_name));
668 loop_file[sizeof(lo64.lo_file_name)] = 0;
669
670 out:
671 close(fd);
672
673 return ret;
674 }
675
676 /* Takes a loop device path (e.g. /dev/loop0) and returns
677 * the associated file (e.g. /images/my_btrfs.img) */
678 static int resolve_loop_device(const char* loop_dev, char* loop_file,
679 int max_len)
680 {
681 int ret;
682 FILE *f;
683 char fmt[20];
684 char p[PATH_MAX];
685 char real_loop_dev[PATH_MAX];
686
687 if (!realpath(loop_dev, real_loop_dev))
688 return -errno;
689 snprintf(p, PATH_MAX, "/sys/block/%s/loop/backing_file", strrchr(real_loop_dev, '/'));
690 if (!(f = fopen(p, "r"))) {
691 if (errno == ENOENT)
692 /*
693 * It's possibly a partitioned loop device, which is
694 * resolvable with loopdev API.
695 */
696 return resolve_loop_device_with_loopdev(loop_dev, loop_file);
697 return -errno;
698 }
699
700 snprintf(fmt, 20, "%%%i[^\n]", max_len-1);
701 ret = fscanf(f, fmt, loop_file);
702 fclose(f);
703 if (ret == EOF)
704 return -errno;
705
706 return 0;
707 }
708
709 /*
710 * Checks whether a and b are identical or device
711 * files associated with the same block device
712 */
713 static int is_same_blk_file(const char* a, const char* b)
714 {
715 struct stat st_buf_a, st_buf_b;
716 char real_a[PATH_MAX];
717 char real_b[PATH_MAX];
718
719 if (!realpath(a, real_a))
720 strncpy_null(real_a, a);
721
722 if (!realpath(b, real_b))
723 strncpy_null(real_b, b);
724
725 /* Identical path? */
726 if (strcmp(real_a, real_b) == 0)
727 return 1;
728
729 if (stat(a, &st_buf_a) < 0 || stat(b, &st_buf_b) < 0) {
730 if (errno == ENOENT)
731 return 0;
732 return -errno;
733 }
734
735 /* Same blockdevice? */
736 if (S_ISBLK(st_buf_a.st_mode) && S_ISBLK(st_buf_b.st_mode) &&
737 st_buf_a.st_rdev == st_buf_b.st_rdev) {
738 return 1;
739 }
740
741 /* Hardlink? */
742 if (st_buf_a.st_dev == st_buf_b.st_dev &&
743 st_buf_a.st_ino == st_buf_b.st_ino) {
744 return 1;
745 }
746
747 return 0;
748 }
749
750 /* checks if a and b are identical or device
751 * files associated with the same block device or
752 * if one file is a loop device that uses the other
753 * file.
754 */
755 static int is_same_loop_file(const char* a, const char* b)
756 {
757 char res_a[PATH_MAX];
758 char res_b[PATH_MAX];
759 const char* final_a = NULL;
760 const char* final_b = NULL;
761 int ret;
762
763 /* Resolve a if it is a loop device */
764 if((ret = is_loop_device(a)) < 0) {
765 if (ret == -ENOENT)
766 return 0;
767 return ret;
768 } else if (ret) {
769 ret = resolve_loop_device(a, res_a, sizeof(res_a));
770 if (ret < 0) {
771 if (errno != EPERM)
772 return ret;
773 } else {
774 final_a = res_a;
775 }
776 } else {
777 final_a = a;
778 }
779
780 /* Resolve b if it is a loop device */
781 if ((ret = is_loop_device(b)) < 0) {
782 if (ret == -ENOENT)
783 return 0;
784 return ret;
785 } else if (ret) {
786 ret = resolve_loop_device(b, res_b, sizeof(res_b));
787 if (ret < 0) {
788 if (errno != EPERM)
789 return ret;
790 } else {
791 final_b = res_b;
792 }
793 } else {
794 final_b = b;
795 }
796
797 return is_same_blk_file(final_a, final_b);
798 }
799
800 /* Checks if a file exists and is a block or regular file*/
801 static int is_existing_blk_or_reg_file(const char* filename)
802 {
803 struct stat st_buf;
804
805 if(stat(filename, &st_buf) < 0) {
806 if(errno == ENOENT)
807 return 0;
808 else
809 return -errno;
810 }
811
812 return (S_ISBLK(st_buf.st_mode) || S_ISREG(st_buf.st_mode));
813 }
814
815 /* Checks if a file is used (directly or indirectly via a loop device)
816 * by a device in fs_devices
817 */
818 static int blk_file_in_dev_list(struct btrfs_fs_devices* fs_devices,
819 const char* file)
820 {
821 int ret;
822 struct btrfs_device *device;
823
824 list_for_each_entry(device, &fs_devices->devices, dev_list) {
825 if((ret = is_same_loop_file(device->name, file)))
826 return ret;
827 }
828
829 return 0;
830 }
831
832 /*
833 * Resolve a pathname to a device mapper node to /dev/mapper/<name>
834 * Returns NULL on invalid input or malloc failure; Other failures
835 * will be handled by the caller using the input pathame.
836 */
837 char *canonicalize_dm_name(const char *ptname)
838 {
839 FILE *f;
840 size_t sz;
841 char path[PATH_MAX], name[PATH_MAX], *res = NULL;
842
843 if (!ptname || !*ptname)
844 return NULL;
845
846 snprintf(path, sizeof(path), "/sys/block/%s/dm/name", ptname);
847 if (!(f = fopen(path, "r")))
848 return NULL;
849
850 /* read <name>\n from sysfs */
851 if (fgets(name, sizeof(name), f) && (sz = strlen(name)) > 1) {
852 name[sz - 1] = '\0';
853 snprintf(path, sizeof(path), "/dev/mapper/%s", name);
854
855 if (access(path, F_OK) == 0)
856 res = strdup(path);
857 }
858 fclose(f);
859 return res;
860 }
861
862 /*
863 * Resolve a pathname to a canonical device node, e.g. /dev/sda1 or
864 * to a device mapper pathname.
865 * Returns NULL on invalid input or malloc failure; Other failures
866 * will be handled by the caller using the input pathame.
867 */
868 char *canonicalize_path(const char *path)
869 {
870 char *canonical, *p;
871
872 if (!path || !*path)
873 return NULL;
874
875 canonical = realpath(path, NULL);
876 if (!canonical)
877 return strdup(path);
878 p = strrchr(canonical, '/');
879 if (p && strncmp(p, "/dm-", 4) == 0 && isdigit(*(p + 4))) {
880 char *dm = canonicalize_dm_name(p + 1);
881
882 if (dm) {
883 free(canonical);
884 return dm;
885 }
886 }
887 return canonical;
888 }
889
890 /*
891 * returns 1 if the device was mounted, < 0 on error or 0 if everything
892 * is safe to continue.
893 */
894 int check_mounted(const char* file)
895 {
896 int fd;
897 int ret;
898
899 fd = open(file, O_RDONLY);
900 if (fd < 0) {
901 error("mount check: cannot open %s: %s", file,
902 strerror(errno));
903 return -errno;
904 }
905
906 ret = check_mounted_where(fd, file, NULL, 0, NULL);
907 close(fd);
908
909 return ret;
910 }
911
912 int check_mounted_where(int fd, const char *file, char *where, int size,
913 struct btrfs_fs_devices **fs_dev_ret)
914 {
915 int ret;
916 u64 total_devs = 1;
917 int is_btrfs;
918 struct btrfs_fs_devices *fs_devices_mnt = NULL;
919 FILE *f;
920 struct mntent *mnt;
921
922 /* scan the initial device */
923 ret = btrfs_scan_one_device(fd, file, &fs_devices_mnt,
924 &total_devs, BTRFS_SUPER_INFO_OFFSET, SBREAD_DEFAULT);
925 is_btrfs = (ret >= 0);
926
927 /* scan other devices */
928 if (is_btrfs && total_devs > 1) {
929 ret = btrfs_scan_devices();
930 if (ret)
931 return ret;
932 }
933
934 /* iterate over the list of currently mounted filesystems */
935 if ((f = setmntent ("/proc/self/mounts", "r")) == NULL)
936 return -errno;
937
938 while ((mnt = getmntent (f)) != NULL) {
939 if(is_btrfs) {
940 if(strcmp(mnt->mnt_type, "btrfs") != 0)
941 continue;
942
943 ret = blk_file_in_dev_list(fs_devices_mnt, mnt->mnt_fsname);
944 } else {
945 /* ignore entries in the mount table that are not
946 associated with a file*/
947 if((ret = is_existing_blk_or_reg_file(mnt->mnt_fsname)) < 0)
948 goto out_mntloop_err;
949 else if(!ret)
950 continue;
951
952 ret = is_same_loop_file(file, mnt->mnt_fsname);
953 }
954
955 if(ret < 0)
956 goto out_mntloop_err;
957 else if(ret)
958 break;
959 }
960
961 /* Did we find an entry in mnt table? */
962 if (mnt && size && where) {
963 strncpy(where, mnt->mnt_dir, size);
964 where[size-1] = 0;
965 }
966 if (fs_dev_ret)
967 *fs_dev_ret = fs_devices_mnt;
968
969 ret = (mnt != NULL);
970
971 out_mntloop_err:
972 endmntent (f);
973
974 return ret;
975 }
976
977 struct pending_dir {
978 struct list_head list;
979 char name[PATH_MAX];
980 };
981
982 int btrfs_register_one_device(const char *fname)
983 {
984 struct btrfs_ioctl_vol_args args;
985 int fd;
986 int ret;
987
988 fd = open("/dev/btrfs-control", O_RDWR);
989 if (fd < 0) {
990 warning(
991 "failed to open /dev/btrfs-control, skipping device registration: %s",
992 strerror(errno));
993 return -errno;
994 }
995 memset(&args, 0, sizeof(args));
996 strncpy_null(args.name, fname);
997 ret = ioctl(fd, BTRFS_IOC_SCAN_DEV, &args);
998 if (ret < 0) {
999 error("device scan failed on '%s': %s", fname,
1000 strerror(errno));
1001 ret = -errno;
1002 }
1003 close(fd);
1004 return ret;
1005 }
1006
1007 /*
1008 * Register all devices in the fs_uuid list created in the user
1009 * space. Ensure btrfs_scan_devices() is called before this func.
1010 */
1011 int btrfs_register_all_devices(void)
1012 {
1013 int err = 0;
1014 int ret = 0;
1015 struct btrfs_fs_devices *fs_devices;
1016 struct btrfs_device *device;
1017 struct list_head *all_uuids;
1018
1019 all_uuids = btrfs_scanned_uuids();
1020
1021 list_for_each_entry(fs_devices, all_uuids, list) {
1022 list_for_each_entry(device, &fs_devices->devices, dev_list) {
1023 if (*device->name)
1024 err = btrfs_register_one_device(device->name);
1025
1026 if (err)
1027 ret++;
1028 }
1029 }
1030
1031 return ret;
1032 }
1033
1034 int btrfs_device_already_in_root(struct btrfs_root *root, int fd,
1035 int super_offset)
1036 {
1037 struct btrfs_super_block *disk_super;
1038 char *buf;
1039 int ret = 0;
1040
1041 buf = malloc(BTRFS_SUPER_INFO_SIZE);
1042 if (!buf) {
1043 ret = -ENOMEM;
1044 goto out;
1045 }
1046 ret = pread(fd, buf, BTRFS_SUPER_INFO_SIZE, super_offset);
1047 if (ret != BTRFS_SUPER_INFO_SIZE)
1048 goto brelse;
1049
1050 ret = 0;
1051 disk_super = (struct btrfs_super_block *)buf;
1052 /*
1053 * Accept devices from the same filesystem, allow partially created
1054 * structures.
1055 */
1056 if (btrfs_super_magic(disk_super) != BTRFS_MAGIC &&
1057 btrfs_super_magic(disk_super) != BTRFS_MAGIC_PARTIAL)
1058 goto brelse;
1059
1060 if (!memcmp(disk_super->fsid, root->fs_info->super_copy->fsid,
1061 BTRFS_FSID_SIZE))
1062 ret = 1;
1063 brelse:
1064 free(buf);
1065 out:
1066 return ret;
1067 }
1068
1069 /*
1070 * Note: this function uses a static per-thread buffer. Do not call this
1071 * function more than 10 times within one argument list!
1072 */
1073 const char *pretty_size_mode(u64 size, unsigned mode)
1074 {
1075 static __thread int ps_index = 0;
1076 static __thread char ps_array[10][32];
1077 char *ret;
1078
1079 ret = ps_array[ps_index];
1080 ps_index++;
1081 ps_index %= 10;
1082 (void)pretty_size_snprintf(size, ret, 32, mode);
1083
1084 return ret;
1085 }
1086
1087 static const char* unit_suffix_binary[] =
1088 { "B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"};
1089 static const char* unit_suffix_decimal[] =
1090 { "B", "kB", "MB", "GB", "TB", "PB", "EB"};
1091
1092 int pretty_size_snprintf(u64 size, char *str, size_t str_size, unsigned unit_mode)
1093 {
1094 int num_divs;
1095 float fraction;
1096 u64 base = 0;
1097 int mult = 0;
1098 const char** suffix = NULL;
1099 u64 last_size;
1100 int negative;
1101
1102 if (str_size == 0)
1103 return 0;
1104
1105 negative = !!(unit_mode & UNITS_NEGATIVE);
1106 unit_mode &= ~UNITS_NEGATIVE;
1107
1108 if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_RAW) {
1109 if (negative)
1110 snprintf(str, str_size, "%lld", size);
1111 else
1112 snprintf(str, str_size, "%llu", size);
1113 return 0;
1114 }
1115
1116 if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_BINARY) {
1117 base = 1024;
1118 mult = 1024;
1119 suffix = unit_suffix_binary;
1120 } else if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_DECIMAL) {
1121 base = 1000;
1122 mult = 1000;
1123 suffix = unit_suffix_decimal;
1124 }
1125
1126 /* Unknown mode */
1127 if (!base) {
1128 fprintf(stderr, "INTERNAL ERROR: unknown unit base, mode %d\n",
1129 unit_mode);
1130 assert(0);
1131 return -1;
1132 }
1133
1134 num_divs = 0;
1135 last_size = size;
1136 switch (unit_mode & UNITS_MODE_MASK) {
1137 case UNITS_TBYTES: base *= mult; num_divs++;
1138 case UNITS_GBYTES: base *= mult; num_divs++;
1139 case UNITS_MBYTES: base *= mult; num_divs++;
1140 case UNITS_KBYTES: num_divs++;
1141 break;
1142 case UNITS_BYTES:
1143 base = 1;
1144 num_divs = 0;
1145 break;
1146 default:
1147 if (negative) {
1148 s64 ssize = (s64)size;
1149 s64 last_ssize = ssize;
1150
1151 while ((ssize < 0 ? -ssize : ssize) >= mult) {
1152 last_ssize = ssize;
1153 ssize /= mult;
1154 num_divs++;
1155 }
1156 last_size = (u64)last_ssize;
1157 } else {
1158 while (size >= mult) {
1159 last_size = size;
1160 size /= mult;
1161 num_divs++;
1162 }
1163 }
1164 /*
1165 * If the value is smaller than base, we didn't do any
1166 * division, in that case, base should be 1, not original
1167 * base, or the unit will be wrong
1168 */
1169 if (num_divs == 0)
1170 base = 1;
1171 }
1172
1173 if (num_divs >= ARRAY_SIZE(unit_suffix_binary)) {
1174 str[0] = '\0';
1175 printf("INTERNAL ERROR: unsupported unit suffix, index %d\n",
1176 num_divs);
1177 assert(0);
1178 return -1;
1179 }
1180
1181 if (negative) {
1182 fraction = (float)(s64)last_size / base;
1183 } else {
1184 fraction = (float)last_size / base;
1185 }
1186
1187 return snprintf(str, str_size, "%.2f%s", fraction, suffix[num_divs]);
1188 }
1189
1190 /*
1191 * __strncpy_null - strncpy with null termination
1192 * @dest: the target array
1193 * @src: the source string
1194 * @n: maximum bytes to copy (size of *dest)
1195 *
1196 * Like strncpy, but ensures destination is null-terminated.
1197 *
1198 * Copies the string pointed to by src, including the terminating null
1199 * byte ('\0'), to the buffer pointed to by dest, up to a maximum
1200 * of n bytes. Then ensure that dest is null-terminated.
1201 */
1202 char *__strncpy_null(char *dest, const char *src, size_t n)
1203 {
1204 strncpy(dest, src, n);
1205 if (n > 0)
1206 dest[n - 1] = '\0';
1207 return dest;
1208 }
1209
1210 /*
1211 * Checks to make sure that the label matches our requirements.
1212 * Returns:
1213 0 if everything is safe and usable
1214 -1 if the label is too long
1215 */
1216 static int check_label(const char *input)
1217 {
1218 int len = strlen(input);
1219
1220 if (len > BTRFS_LABEL_SIZE - 1) {
1221 error("label %s is too long (max %d)", input,
1222 BTRFS_LABEL_SIZE - 1);
1223 return -1;
1224 }
1225
1226 return 0;
1227 }
1228
1229 static int set_label_unmounted(const char *dev, const char *label)
1230 {
1231 struct btrfs_trans_handle *trans;
1232 struct btrfs_root *root;
1233 int ret;
1234
1235 ret = check_mounted(dev);
1236 if (ret < 0) {
1237 error("checking mount status of %s failed: %d", dev, ret);
1238 return -1;
1239 }
1240 if (ret > 0) {
1241 error("device %s is mounted, use mount point", dev);
1242 return -1;
1243 }
1244
1245 /* Open the super_block at the default location
1246 * and as read-write.
1247 */
1248 root = open_ctree(dev, 0, OPEN_CTREE_WRITES);
1249 if (!root) /* errors are printed by open_ctree() */
1250 return -1;
1251
1252 trans = btrfs_start_transaction(root, 1);
1253 BUG_ON(IS_ERR(trans));
1254 __strncpy_null(root->fs_info->super_copy->label, label, BTRFS_LABEL_SIZE - 1);
1255
1256 btrfs_commit_transaction(trans, root);
1257
1258 /* Now we close it since we are done. */
1259 close_ctree(root);
1260 return 0;
1261 }
1262
1263 static int set_label_mounted(const char *mount_path, const char *labelp)
1264 {
1265 int fd;
1266 char label[BTRFS_LABEL_SIZE];
1267
1268 fd = open(mount_path, O_RDONLY | O_NOATIME);
1269 if (fd < 0) {
1270 error("unable to access %s: %s", mount_path, strerror(errno));
1271 return -1;
1272 }
1273
1274 memset(label, 0, sizeof(label));
1275 __strncpy_null(label, labelp, BTRFS_LABEL_SIZE - 1);
1276 if (ioctl(fd, BTRFS_IOC_SET_FSLABEL, label) < 0) {
1277 error("unable to set label of %s: %s", mount_path,
1278 strerror(errno));
1279 close(fd);
1280 return -1;
1281 }
1282
1283 close(fd);
1284 return 0;
1285 }
1286
1287 int get_label_unmounted(const char *dev, char *label)
1288 {
1289 struct btrfs_root *root;
1290 int ret;
1291
1292 ret = check_mounted(dev);
1293 if (ret < 0) {
1294 error("checking mount status of %s failed: %d", dev, ret);
1295 return -1;
1296 }
1297
1298 /* Open the super_block at the default location
1299 * and as read-only.
1300 */
1301 root = open_ctree(dev, 0, 0);
1302 if(!root)
1303 return -1;
1304
1305 __strncpy_null(label, root->fs_info->super_copy->label,
1306 BTRFS_LABEL_SIZE - 1);
1307
1308 /* Now we close it since we are done. */
1309 close_ctree(root);
1310 return 0;
1311 }
1312
1313 /*
1314 * If a partition is mounted, try to get the filesystem label via its
1315 * mounted path rather than device. Return the corresponding error
1316 * the user specified the device path.
1317 */
1318 int get_label_mounted(const char *mount_path, char *labelp)
1319 {
1320 char label[BTRFS_LABEL_SIZE];
1321 int fd;
1322 int ret;
1323
1324 fd = open(mount_path, O_RDONLY | O_NOATIME);
1325 if (fd < 0) {
1326 error("unable to access %s: %s", mount_path, strerror(errno));
1327 return -1;
1328 }
1329
1330 memset(label, '\0', sizeof(label));
1331 ret = ioctl(fd, BTRFS_IOC_GET_FSLABEL, label);
1332 if (ret < 0) {
1333 if (errno != ENOTTY)
1334 error("unable to get label of %s: %s", mount_path,
1335 strerror(errno));
1336 ret = -errno;
1337 close(fd);
1338 return ret;
1339 }
1340
1341 __strncpy_null(labelp, label, BTRFS_LABEL_SIZE - 1);
1342 close(fd);
1343 return 0;
1344 }
1345
1346 int get_label(const char *btrfs_dev, char *label)
1347 {
1348 int ret;
1349
1350 ret = is_existing_blk_or_reg_file(btrfs_dev);
1351 if (!ret)
1352 ret = get_label_mounted(btrfs_dev, label);
1353 else if (ret > 0)
1354 ret = get_label_unmounted(btrfs_dev, label);
1355
1356 return ret;
1357 }
1358
1359 int set_label(const char *btrfs_dev, const char *label)
1360 {
1361 int ret;
1362
1363 if (check_label(label))
1364 return -1;
1365
1366 ret = is_existing_blk_or_reg_file(btrfs_dev);
1367 if (!ret)
1368 ret = set_label_mounted(btrfs_dev, label);
1369 else if (ret > 0)
1370 ret = set_label_unmounted(btrfs_dev, label);
1371
1372 return ret;
1373 }
1374
1375 /*
1376 * A not-so-good version fls64. No fascinating optimization since
1377 * no one except parse_size use it
1378 */
1379 static int fls64(u64 x)
1380 {
1381 int i;
1382
1383 for (i = 0; i <64; i++)
1384 if (x << i & (1ULL << 63))
1385 return 64 - i;
1386 return 64 - i;
1387 }
1388
1389 u64 parse_size(char *s)
1390 {
1391 char c;
1392 char *endptr;
1393 u64 mult = 1;
1394 u64 ret;
1395
1396 if (!s) {
1397 error("size value is empty");
1398 exit(1);
1399 }
1400 if (s[0] == '-') {
1401 error("size value '%s' is less equal than 0", s);
1402 exit(1);
1403 }
1404 ret = strtoull(s, &endptr, 10);
1405 if (endptr == s) {
1406 error("size value '%s' is invalid", s);
1407 exit(1);
1408 }
1409 if (endptr[0] && endptr[1]) {
1410 error("illegal suffix contains character '%c' in wrong position",
1411 endptr[1]);
1412 exit(1);
1413 }
1414 /*
1415 * strtoll returns LLONG_MAX when overflow, if this happens,
1416 * need to call strtoull to get the real size
1417 */
1418 if (errno == ERANGE && ret == ULLONG_MAX) {
1419 error("size value '%s' is too large for u64", s);
1420 exit(1);
1421 }
1422 if (endptr[0]) {
1423 c = tolower(endptr[0]);
1424 switch (c) {
1425 case 'e':
1426 mult *= 1024;
1427 /* fallthrough */
1428 case 'p':
1429 mult *= 1024;
1430 /* fallthrough */
1431 case 't':
1432 mult *= 1024;
1433 /* fallthrough */
1434 case 'g':
1435 mult *= 1024;
1436 /* fallthrough */
1437 case 'm':
1438 mult *= 1024;
1439 /* fallthrough */
1440 case 'k':
1441 mult *= 1024;
1442 /* fallthrough */
1443 case 'b':
1444 break;
1445 default:
1446 error("unknown size descriptor '%c'", c);
1447 exit(1);
1448 }
1449 }
1450 /* Check whether ret * mult overflow */
1451 if (fls64(ret) + fls64(mult) - 1 > 64) {
1452 error("size value '%s' is too large for u64", s);
1453 exit(1);
1454 }
1455 ret *= mult;
1456 return ret;
1457 }
1458
1459 u64 parse_qgroupid(const char *p)
1460 {
1461 char *s = strchr(p, '/');
1462 const char *ptr_src_end = p + strlen(p);
1463 char *ptr_parse_end = NULL;
1464 u64 level;
1465 u64 id;
1466 int fd;
1467 int ret = 0;
1468
1469 if (p[0] == '/')
1470 goto path;
1471
1472 /* Numeric format like '0/257' is the primary case */
1473 if (!s) {
1474 id = strtoull(p, &ptr_parse_end, 10);
1475 if (ptr_parse_end != ptr_src_end)
1476 goto path;
1477 return id;
1478 }
1479 level = strtoull(p, &ptr_parse_end, 10);
1480 if (ptr_parse_end != s)
1481 goto path;
1482
1483 id = strtoull(s + 1, &ptr_parse_end, 10);
1484 if (ptr_parse_end != ptr_src_end)
1485 goto path;
1486
1487 return (level << BTRFS_QGROUP_LEVEL_SHIFT) | id;
1488
1489 path:
1490 /* Path format like subv at 'my_subvol' is the fallback case */
1491 ret = test_issubvolume(p);
1492 if (ret < 0 || !ret)
1493 goto err;
1494 fd = open(p, O_RDONLY);
1495 if (fd < 0)
1496 goto err;
1497 ret = lookup_path_rootid(fd, &id);
1498 if (ret)
1499 error("failed to lookup root id: %s", strerror(-ret));
1500 close(fd);
1501 if (ret < 0)
1502 goto err;
1503 return id;
1504
1505 err:
1506 error("invalid qgroupid or subvolume path: %s", p);
1507 exit(-1);
1508 }
1509
1510 int open_file_or_dir3(const char *fname, DIR **dirstream, int open_flags)
1511 {
1512 int ret;
1513 struct stat st;
1514 int fd;
1515
1516 ret = stat(fname, &st);
1517 if (ret < 0) {
1518 return -1;
1519 }
1520 if (S_ISDIR(st.st_mode)) {
1521 *dirstream = opendir(fname);
1522 if (!*dirstream)
1523 return -1;
1524 fd = dirfd(*dirstream);
1525 } else if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)) {
1526 fd = open(fname, open_flags);
1527 } else {
1528 /*
1529 * we set this on purpose, in case the caller output
1530 * strerror(errno) as success
1531 */
1532 errno = EINVAL;
1533 return -1;
1534 }
1535 if (fd < 0) {
1536 fd = -1;
1537 if (*dirstream) {
1538 closedir(*dirstream);
1539 *dirstream = NULL;
1540 }
1541 }
1542 return fd;
1543 }
1544
1545 int open_file_or_dir(const char *fname, DIR **dirstream)
1546 {
1547 return open_file_or_dir3(fname, dirstream, O_RDWR);
1548 }
1549
1550 void close_file_or_dir(int fd, DIR *dirstream)
1551 {
1552 if (dirstream)
1553 closedir(dirstream);
1554 else if (fd >= 0)
1555 close(fd);
1556 }
1557
1558 int get_device_info(int fd, u64 devid,
1559 struct btrfs_ioctl_dev_info_args *di_args)
1560 {
1561 int ret;
1562
1563 di_args->devid = devid;
1564 memset(&di_args->uuid, '\0', sizeof(di_args->uuid));
1565
1566 ret = ioctl(fd, BTRFS_IOC_DEV_INFO, di_args);
1567 return ret < 0 ? -errno : 0;
1568 }
1569
1570 static u64 find_max_device_id(struct btrfs_ioctl_search_args *search_args,
1571 int nr_items)
1572 {
1573 struct btrfs_dev_item *dev_item;
1574 char *buf = search_args->buf;
1575
1576 buf += (nr_items - 1) * (sizeof(struct btrfs_ioctl_search_header)
1577 + sizeof(struct btrfs_dev_item));
1578 buf += sizeof(struct btrfs_ioctl_search_header);
1579
1580 dev_item = (struct btrfs_dev_item *)buf;
1581
1582 return btrfs_stack_device_id(dev_item);
1583 }
1584
1585 static int search_chunk_tree_for_fs_info(int fd,
1586 struct btrfs_ioctl_fs_info_args *fi_args)
1587 {
1588 int ret;
1589 int max_items;
1590 u64 start_devid = 1;
1591 struct btrfs_ioctl_search_args search_args;
1592 struct btrfs_ioctl_search_key *search_key = &search_args.key;
1593
1594 fi_args->num_devices = 0;
1595
1596 max_items = BTRFS_SEARCH_ARGS_BUFSIZE
1597 / (sizeof(struct btrfs_ioctl_search_header)
1598 + sizeof(struct btrfs_dev_item));
1599
1600 search_key->tree_id = BTRFS_CHUNK_TREE_OBJECTID;
1601 search_key->min_objectid = BTRFS_DEV_ITEMS_OBJECTID;
1602 search_key->max_objectid = BTRFS_DEV_ITEMS_OBJECTID;
1603 search_key->min_type = BTRFS_DEV_ITEM_KEY;
1604 search_key->max_type = BTRFS_DEV_ITEM_KEY;
1605 search_key->min_transid = 0;
1606 search_key->max_transid = (u64)-1;
1607 search_key->nr_items = max_items;
1608 search_key->max_offset = (u64)-1;
1609
1610 again:
1611 search_key->min_offset = start_devid;
1612
1613 ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &search_args);
1614 if (ret < 0)
1615 return -errno;
1616
1617 fi_args->num_devices += (u64)search_key->nr_items;
1618
1619 if (search_key->nr_items == max_items) {
1620 start_devid = find_max_device_id(&search_args,
1621 search_key->nr_items) + 1;
1622 goto again;
1623 }
1624
1625 /* get the lastest max_id to stay consistent with the num_devices */
1626 if (search_key->nr_items == 0)
1627 /*
1628 * last tree_search returns an empty buf, use the devid of
1629 * the last dev_item of the previous tree_search
1630 */
1631 fi_args->max_id = start_devid - 1;
1632 else
1633 fi_args->max_id = find_max_device_id(&search_args,
1634 search_key->nr_items);
1635
1636 return 0;
1637 }
1638
1639 /*
1640 * For a given path, fill in the ioctl fs_ and info_ args.
1641 * If the path is a btrfs mountpoint, fill info for all devices.
1642 * If the path is a btrfs device, fill in only that device.
1643 *
1644 * The path provided must be either on a mounted btrfs fs,
1645 * or be a mounted btrfs device.
1646 *
1647 * Returns 0 on success, or a negative errno.
1648 */
1649 int get_fs_info(const char *path, struct btrfs_ioctl_fs_info_args *fi_args,
1650 struct btrfs_ioctl_dev_info_args **di_ret)
1651 {
1652 int fd = -1;
1653 int ret = 0;
1654 int ndevs = 0;
1655 u64 last_devid = 0;
1656 int replacing = 0;
1657 struct btrfs_fs_devices *fs_devices_mnt = NULL;
1658 struct btrfs_ioctl_dev_info_args *di_args;
1659 struct btrfs_ioctl_dev_info_args tmp;
1660 char mp[PATH_MAX];
1661 DIR *dirstream = NULL;
1662
1663 memset(fi_args, 0, sizeof(*fi_args));
1664
1665 if (is_block_device(path) == 1) {
1666 struct btrfs_super_block *disk_super;
1667 char buf[BTRFS_SUPER_INFO_SIZE];
1668
1669 /* Ensure it's mounted, then set path to the mountpoint */
1670 fd = open(path, O_RDONLY);
1671 if (fd < 0) {
1672 ret = -errno;
1673 error("cannot open %s: %s", path, strerror(errno));
1674 goto out;
1675 }
1676 ret = check_mounted_where(fd, path, mp, sizeof(mp),
1677 &fs_devices_mnt);
1678 if (!ret) {
1679 ret = -EINVAL;
1680 goto out;
1681 }
1682 if (ret < 0)
1683 goto out;
1684 path = mp;
1685 /* Only fill in this one device */
1686 fi_args->num_devices = 1;
1687
1688 disk_super = (struct btrfs_super_block *)buf;
1689 ret = btrfs_read_dev_super(fd, disk_super,
1690 BTRFS_SUPER_INFO_OFFSET, 0);
1691 if (ret < 0) {
1692 ret = -EIO;
1693 goto out;
1694 }
1695 last_devid = btrfs_stack_device_id(&disk_super->dev_item);
1696 fi_args->max_id = last_devid;
1697
1698 memcpy(fi_args->fsid, fs_devices_mnt->fsid, BTRFS_FSID_SIZE);
1699 close(fd);
1700 }
1701
1702 /* at this point path must not be for a block device */
1703 fd = open_file_or_dir(path, &dirstream);
1704 if (fd < 0) {
1705 ret = -errno;
1706 goto out;
1707 }
1708
1709 /* fill in fi_args if not just a single device */
1710 if (fi_args->num_devices != 1) {
1711 ret = ioctl(fd, BTRFS_IOC_FS_INFO, fi_args);
1712 if (ret < 0) {
1713 ret = -errno;
1714 goto out;
1715 }
1716
1717 /*
1718 * The fs_args->num_devices does not include seed devices
1719 */
1720 ret = search_chunk_tree_for_fs_info(fd, fi_args);
1721 if (ret)
1722 goto out;
1723
1724 /*
1725 * search_chunk_tree_for_fs_info() will lacks the devid 0
1726 * so manual probe for it here.
1727 */
1728 ret = get_device_info(fd, 0, &tmp);
1729 if (!ret) {
1730 fi_args->num_devices++;
1731 ndevs++;
1732 replacing = 1;
1733 if (last_devid == 0)
1734 last_devid++;
1735 }
1736 }
1737
1738 if (!fi_args->num_devices)
1739 goto out;
1740
1741 di_args = *di_ret = malloc((fi_args->num_devices) * sizeof(*di_args));
1742 if (!di_args) {
1743 ret = -errno;
1744 goto out;
1745 }
1746
1747 if (replacing)
1748 memcpy(di_args, &tmp, sizeof(tmp));
1749 for (; last_devid <= fi_args->max_id; last_devid++) {
1750 ret = get_device_info(fd, last_devid, &di_args[ndevs]);
1751 if (ret == -ENODEV)
1752 continue;
1753 if (ret)
1754 goto out;
1755 ndevs++;
1756 }
1757
1758 /*
1759 * only when the only dev we wanted to find is not there then
1760 * let any error be returned
1761 */
1762 if (fi_args->num_devices != 1) {
1763 BUG_ON(ndevs == 0);
1764 ret = 0;
1765 }
1766
1767 out:
1768 close_file_or_dir(fd, dirstream);
1769 return ret;
1770 }
1771
1772 int get_fsid(const char *path, u8 *fsid, int silent)
1773 {
1774 int ret;
1775 int fd;
1776 struct btrfs_ioctl_fs_info_args args;
1777
1778 fd = open(path, O_RDONLY);
1779 if (fd < 0) {
1780 ret = -errno;
1781 if (!silent)
1782 error("failed to open %s: %s", path,
1783 strerror(-ret));
1784 goto out;
1785 }
1786
1787 ret = ioctl(fd, BTRFS_IOC_FS_INFO, &args);
1788 if (ret < 0) {
1789 ret = -errno;
1790 goto out;
1791 }
1792
1793 memcpy(fsid, args.fsid, BTRFS_FSID_SIZE);
1794 ret = 0;
1795
1796 out:
1797 if (fd != -1)
1798 close(fd);
1799 return ret;
1800 }
1801
1802 int is_seen_fsid(u8 *fsid, struct seen_fsid *seen_fsid_hash[])
1803 {
1804 u8 hash = fsid[0];
1805 int slot = hash % SEEN_FSID_HASH_SIZE;
1806 struct seen_fsid *seen = seen_fsid_hash[slot];
1807
1808 while (seen) {
1809 if (memcmp(seen->fsid, fsid, BTRFS_FSID_SIZE) == 0)
1810 return 1;
1811
1812 seen = seen->next;
1813 }
1814
1815 return 0;
1816 }
1817
1818 int add_seen_fsid(u8 *fsid, struct seen_fsid *seen_fsid_hash[],
1819 int fd, DIR *dirstream)
1820 {
1821 u8 hash = fsid[0];
1822 int slot = hash % SEEN_FSID_HASH_SIZE;
1823 struct seen_fsid *seen = seen_fsid_hash[slot];
1824 struct seen_fsid *alloc;
1825
1826 if (!seen)
1827 goto insert;
1828
1829 while (1) {
1830 if (memcmp(seen->fsid, fsid, BTRFS_FSID_SIZE) == 0)
1831 return -EEXIST;
1832
1833 if (!seen->next)
1834 break;
1835
1836 seen = seen->next;
1837 }
1838
1839 insert:
1840 alloc = malloc(sizeof(*alloc));
1841 if (!alloc)
1842 return -ENOMEM;
1843
1844 alloc->next = NULL;
1845 memcpy(alloc->fsid, fsid, BTRFS_FSID_SIZE);
1846 alloc->fd = fd;
1847 alloc->dirstream = dirstream;
1848
1849 if (seen)
1850 seen->next = alloc;
1851 else
1852 seen_fsid_hash[slot] = alloc;
1853
1854 return 0;
1855 }
1856
1857 void free_seen_fsid(struct seen_fsid *seen_fsid_hash[])
1858 {
1859 int slot;
1860 struct seen_fsid *seen;
1861 struct seen_fsid *next;
1862
1863 for (slot = 0; slot < SEEN_FSID_HASH_SIZE; slot++) {
1864 seen = seen_fsid_hash[slot];
1865 while (seen) {
1866 next = seen->next;
1867 close_file_or_dir(seen->fd, seen->dirstream);
1868 free(seen);
1869 seen = next;
1870 }
1871 seen_fsid_hash[slot] = NULL;
1872 }
1873 }
1874
1875 static int group_profile_devs_min(u64 flag)
1876 {
1877 switch (flag & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
1878 case 0: /* single */
1879 case BTRFS_BLOCK_GROUP_DUP:
1880 return 1;
1881 case BTRFS_BLOCK_GROUP_RAID0:
1882 case BTRFS_BLOCK_GROUP_RAID1:
1883 case BTRFS_BLOCK_GROUP_RAID5:
1884 return 2;
1885 case BTRFS_BLOCK_GROUP_RAID6:
1886 return 3;
1887 case BTRFS_BLOCK_GROUP_RAID10:
1888 return 4;
1889 default:
1890 return -1;
1891 }
1892 }
1893
1894 int test_num_disk_vs_raid(u64 metadata_profile, u64 data_profile,
1895 u64 dev_cnt, int mixed, int ssd)
1896 {
1897 u64 allowed = 0;
1898 u64 profile = metadata_profile | data_profile;
1899
1900 switch (dev_cnt) {
1901 default:
1902 case 4:
1903 allowed |= BTRFS_BLOCK_GROUP_RAID10;
1904 case 3:
1905 allowed |= BTRFS_BLOCK_GROUP_RAID6;
1906 case 2:
1907 allowed |= BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
1908 BTRFS_BLOCK_GROUP_RAID5;
1909 case 1:
1910 allowed |= BTRFS_BLOCK_GROUP_DUP;
1911 }
1912
1913 if (dev_cnt > 1 && profile & BTRFS_BLOCK_GROUP_DUP) {
1914 warning("DUP is not recommended on filesystem with multiple devices");
1915 }
1916 if (metadata_profile & ~allowed) {
1917 fprintf(stderr,
1918 "ERROR: unable to create FS with metadata profile %s "
1919 "(have %llu devices but %d devices are required)\n",
1920 btrfs_group_profile_str(metadata_profile), dev_cnt,
1921 group_profile_devs_min(metadata_profile));
1922 return 1;
1923 }
1924 if (data_profile & ~allowed) {
1925 fprintf(stderr,
1926 "ERROR: unable to create FS with data profile %s "
1927 "(have %llu devices but %d devices are required)\n",
1928 btrfs_group_profile_str(data_profile), dev_cnt,
1929 group_profile_devs_min(data_profile));
1930 return 1;
1931 }
1932
1933 if (dev_cnt == 3 && profile & BTRFS_BLOCK_GROUP_RAID6) {
1934 warning("RAID6 is not recommended on filesystem with 3 devices only");
1935 }
1936 if (dev_cnt == 2 && profile & BTRFS_BLOCK_GROUP_RAID5) {
1937 warning("RAID5 is not recommended on filesystem with 2 devices only");
1938 }
1939 warning_on(!mixed && (data_profile & BTRFS_BLOCK_GROUP_DUP) && ssd,
1940 "DUP may not actually lead to 2 copies on the device, see manual page");
1941
1942 return 0;
1943 }
1944
1945 int group_profile_max_safe_loss(u64 flags)
1946 {
1947 switch (flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
1948 case 0: /* single */
1949 case BTRFS_BLOCK_GROUP_DUP:
1950 case BTRFS_BLOCK_GROUP_RAID0:
1951 return 0;
1952 case BTRFS_BLOCK_GROUP_RAID1:
1953 case BTRFS_BLOCK_GROUP_RAID5:
1954 case BTRFS_BLOCK_GROUP_RAID10:
1955 return 1;
1956 case BTRFS_BLOCK_GROUP_RAID6:
1957 return 2;
1958 default:
1959 return -1;
1960 }
1961 }
1962
1963 int btrfs_scan_devices(void)
1964 {
1965 int fd = -1;
1966 int ret;
1967 u64 num_devices;
1968 struct btrfs_fs_devices *tmp_devices;
1969 blkid_dev_iterate iter = NULL;
1970 blkid_dev dev = NULL;
1971 blkid_cache cache = NULL;
1972 char path[PATH_MAX];
1973
1974 if (btrfs_scan_done)
1975 return 0;
1976
1977 if (blkid_get_cache(&cache, NULL) < 0) {
1978 error("blkid cache get failed");
1979 return 1;
1980 }
1981 blkid_probe_all(cache);
1982 iter = blkid_dev_iterate_begin(cache);
1983 blkid_dev_set_search(iter, "TYPE", "btrfs");
1984 while (blkid_dev_next(iter, &dev) == 0) {
1985 dev = blkid_verify(cache, dev);
1986 if (!dev)
1987 continue;
1988 /* if we are here its definitely a btrfs disk*/
1989 strncpy_null(path, blkid_dev_devname(dev));
1990
1991 fd = open(path, O_RDONLY);
1992 if (fd < 0) {
1993 error("cannot open %s: %s", path, strerror(errno));
1994 continue;
1995 }
1996 ret = btrfs_scan_one_device(fd, path, &tmp_devices,
1997 &num_devices, BTRFS_SUPER_INFO_OFFSET,
1998 SBREAD_DEFAULT);
1999 if (ret) {
2000 error("cannot scan %s: %s", path, strerror(-ret));
2001 close (fd);
2002 continue;
2003 }
2004
2005 close(fd);
2006 }
2007 blkid_dev_iterate_end(iter);
2008 blkid_put_cache(cache);
2009
2010 btrfs_scan_done = 1;
2011
2012 return 0;
2013 }
2014
2015 /*
2016 * This reads a line from the stdin and only returns non-zero if the
2017 * first whitespace delimited token is a case insensitive match with yes
2018 * or y.
2019 */
2020 int ask_user(const char *question)
2021 {
2022 char buf[30] = {0,};
2023 char *saveptr = NULL;
2024 char *answer;
2025
2026 printf("%s [y/N]: ", question);
2027
2028 return fgets(buf, sizeof(buf) - 1, stdin) &&
2029 (answer = strtok_r(buf, " \t\n\r", &saveptr)) &&
2030 (!strcasecmp(answer, "yes") || !strcasecmp(answer, "y"));
2031 }
2032
2033 /*
2034 * return 0 if a btrfs mount point is found
2035 * return 1 if a mount point is found but not btrfs
2036 * return <0 if something goes wrong
2037 */
2038 int find_mount_root(const char *path, char **mount_root)
2039 {
2040 FILE *mnttab;
2041 int fd;
2042 struct mntent *ent;
2043 int len;
2044 int ret;
2045 int not_btrfs = 1;
2046 int longest_matchlen = 0;
2047 char *longest_match = NULL;
2048
2049 fd = open(path, O_RDONLY | O_NOATIME);
2050 if (fd < 0)
2051 return -errno;
2052 close(fd);
2053
2054 mnttab = setmntent("/proc/self/mounts", "r");
2055 if (!mnttab)
2056 return -errno;
2057
2058 while ((ent = getmntent(mnttab))) {
2059 len = strlen(ent->mnt_dir);
2060 if (strncmp(ent->mnt_dir, path, len) == 0) {
2061 /* match found and use the latest match */
2062 if (longest_matchlen <= len) {
2063 free(longest_match);
2064 longest_matchlen = len;
2065 longest_match = strdup(ent->mnt_dir);
2066 not_btrfs = strcmp(ent->mnt_type, "btrfs");
2067 }
2068 }
2069 }
2070 endmntent(mnttab);
2071
2072 if (!longest_match)
2073 return -ENOENT;
2074 if (not_btrfs) {
2075 free(longest_match);
2076 return 1;
2077 }
2078
2079 ret = 0;
2080 *mount_root = realpath(longest_match, NULL);
2081 if (!*mount_root)
2082 ret = -errno;
2083
2084 free(longest_match);
2085 return ret;
2086 }
2087
2088 /*
2089 * Test if path is a directory
2090 * Returns:
2091 * 0 - path exists but it is not a directory
2092 * 1 - path exists and it is a directory
2093 * < 0 - error
2094 */
2095 int test_isdir(const char *path)
2096 {
2097 struct stat st;
2098 int ret;
2099
2100 ret = stat(path, &st);
2101 if (ret < 0)
2102 return -errno;
2103
2104 return !!S_ISDIR(st.st_mode);
2105 }
2106
2107 void units_set_mode(unsigned *units, unsigned mode)
2108 {
2109 unsigned base = *units & UNITS_MODE_MASK;
2110
2111 *units = base | mode;
2112 }
2113
2114 void units_set_base(unsigned *units, unsigned base)
2115 {
2116 unsigned mode = *units & ~UNITS_MODE_MASK;
2117
2118 *units = base | mode;
2119 }
2120
2121 int find_next_key(struct btrfs_path *path, struct btrfs_key *key)
2122 {
2123 int level;
2124
2125 for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
2126 if (!path->nodes[level])
2127 break;
2128 if (path->slots[level] + 1 >=
2129 btrfs_header_nritems(path->nodes[level]))
2130 continue;
2131 if (level == 0)
2132 btrfs_item_key_to_cpu(path->nodes[level], key,
2133 path->slots[level] + 1);
2134 else
2135 btrfs_node_key_to_cpu(path->nodes[level], key,
2136 path->slots[level] + 1);
2137 return 0;
2138 }
2139 return 1;
2140 }
2141
2142 const char* btrfs_group_type_str(u64 flag)
2143 {
2144 u64 mask = BTRFS_BLOCK_GROUP_TYPE_MASK |
2145 BTRFS_SPACE_INFO_GLOBAL_RSV;
2146
2147 switch (flag & mask) {
2148 case BTRFS_BLOCK_GROUP_DATA:
2149 return "Data";
2150 case BTRFS_BLOCK_GROUP_SYSTEM:
2151 return "System";
2152 case BTRFS_BLOCK_GROUP_METADATA:
2153 return "Metadata";
2154 case BTRFS_BLOCK_GROUP_DATA|BTRFS_BLOCK_GROUP_METADATA:
2155 return "Data+Metadata";
2156 case BTRFS_SPACE_INFO_GLOBAL_RSV:
2157 return "GlobalReserve";
2158 default:
2159 return "unknown";
2160 }
2161 }
2162
2163 const char* btrfs_group_profile_str(u64 flag)
2164 {
2165 switch (flag & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
2166 case 0:
2167 return "single";
2168 case BTRFS_BLOCK_GROUP_RAID0:
2169 return "RAID0";
2170 case BTRFS_BLOCK_GROUP_RAID1:
2171 return "RAID1";
2172 case BTRFS_BLOCK_GROUP_RAID5:
2173 return "RAID5";
2174 case BTRFS_BLOCK_GROUP_RAID6:
2175 return "RAID6";
2176 case BTRFS_BLOCK_GROUP_DUP:
2177 return "DUP";
2178 case BTRFS_BLOCK_GROUP_RAID10:
2179 return "RAID10";
2180 default:
2181 return "unknown";
2182 }
2183 }
2184
2185 u64 disk_size(const char *path)
2186 {
2187 struct statfs sfs;
2188
2189 if (statfs(path, &sfs) < 0)
2190 return 0;
2191 else
2192 return sfs.f_bsize * sfs.f_blocks;
2193 }
2194
2195 u64 get_partition_size(const char *dev)
2196 {
2197 u64 result;
2198 int fd = open(dev, O_RDONLY);
2199
2200 if (fd < 0)
2201 return 0;
2202 if (ioctl(fd, BLKGETSIZE64, &result) < 0) {
2203 close(fd);
2204 return 0;
2205 }
2206 close(fd);
2207
2208 return result;
2209 }
2210
2211 /*
2212 * Check if the BTRFS_IOC_TREE_SEARCH_V2 ioctl is supported on a given
2213 * filesystem, opened at fd
2214 */
2215 int btrfs_tree_search2_ioctl_supported(int fd)
2216 {
2217 struct btrfs_ioctl_search_args_v2 *args2;
2218 struct btrfs_ioctl_search_key *sk;
2219 int args2_size = 1024;
2220 char args2_buf[args2_size];
2221 int ret;
2222
2223 args2 = (struct btrfs_ioctl_search_args_v2 *)args2_buf;
2224 sk = &(args2->key);
2225
2226 /*
2227 * Search for the extent tree item in the root tree.
2228 */
2229 sk->tree_id = BTRFS_ROOT_TREE_OBJECTID;
2230 sk->min_objectid = BTRFS_EXTENT_TREE_OBJECTID;
2231 sk->max_objectid = BTRFS_EXTENT_TREE_OBJECTID;
2232 sk->min_type = BTRFS_ROOT_ITEM_KEY;
2233 sk->max_type = BTRFS_ROOT_ITEM_KEY;
2234 sk->min_offset = 0;
2235 sk->max_offset = (u64)-1;
2236 sk->min_transid = 0;
2237 sk->max_transid = (u64)-1;
2238 sk->nr_items = 1;
2239 args2->buf_size = args2_size - sizeof(struct btrfs_ioctl_search_args_v2);
2240 ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH_V2, args2);
2241 if (ret == -EOPNOTSUPP)
2242 return 0;
2243 else if (ret == 0)
2244 return 1;
2245 return ret;
2246 }
2247
2248 int btrfs_check_nodesize(u32 nodesize, u32 sectorsize, u64 features)
2249 {
2250 if (nodesize < sectorsize) {
2251 error("illegal nodesize %u (smaller than %u)",
2252 nodesize, sectorsize);
2253 return -1;
2254 } else if (nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
2255 error("illegal nodesize %u (larger than %u)",
2256 nodesize, BTRFS_MAX_METADATA_BLOCKSIZE);
2257 return -1;
2258 } else if (nodesize & (sectorsize - 1)) {
2259 error("illegal nodesize %u (not aligned to %u)",
2260 nodesize, sectorsize);
2261 return -1;
2262 } else if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS &&
2263 nodesize != sectorsize) {
2264 error("illegal nodesize %u (not equal to %u for mixed block group)",
2265 nodesize, sectorsize);
2266 return -1;
2267 }
2268 return 0;
2269 }
2270
2271 /*
2272 * Copy a path argument from SRC to DEST and check the SRC length if it's at
2273 * most PATH_MAX and fits into DEST. DESTLEN is supposed to be exact size of
2274 * the buffer.
2275 * The destination buffer is zero terminated.
2276 * Return < 0 for error, 0 otherwise.
2277 */
2278 int arg_copy_path(char *dest, const char *src, int destlen)
2279 {
2280 size_t len = strlen(src);
2281
2282 if (len >= PATH_MAX || len >= destlen)
2283 return -ENAMETOOLONG;
2284
2285 __strncpy_null(dest, src, destlen);
2286
2287 return 0;
2288 }
2289
2290 unsigned int get_unit_mode_from_arg(int *argc, char *argv[], int df_mode)
2291 {
2292 unsigned int unit_mode = UNITS_DEFAULT;
2293 int arg_i;
2294 int arg_end;
2295
2296 for (arg_i = 0; arg_i < *argc; arg_i++) {
2297 if (!strcmp(argv[arg_i], "--"))
2298 break;
2299
2300 if (!strcmp(argv[arg_i], "--raw")) {
2301 unit_mode = UNITS_RAW;
2302 argv[arg_i] = NULL;
2303 continue;
2304 }
2305 if (!strcmp(argv[arg_i], "--human-readable")) {
2306 unit_mode = UNITS_HUMAN_BINARY;
2307 argv[arg_i] = NULL;
2308 continue;
2309 }
2310
2311 if (!strcmp(argv[arg_i], "--iec")) {
2312 units_set_mode(&unit_mode, UNITS_BINARY);
2313 argv[arg_i] = NULL;
2314 continue;
2315 }
2316 if (!strcmp(argv[arg_i], "--si")) {
2317 units_set_mode(&unit_mode, UNITS_DECIMAL);
2318 argv[arg_i] = NULL;
2319 continue;
2320 }
2321
2322 if (!strcmp(argv[arg_i], "--kbytes")) {
2323 units_set_base(&unit_mode, UNITS_KBYTES);
2324 argv[arg_i] = NULL;
2325 continue;
2326 }
2327 if (!strcmp(argv[arg_i], "--mbytes")) {
2328 units_set_base(&unit_mode, UNITS_MBYTES);
2329 argv[arg_i] = NULL;
2330 continue;
2331 }
2332 if (!strcmp(argv[arg_i], "--gbytes")) {
2333 units_set_base(&unit_mode, UNITS_GBYTES);
2334 argv[arg_i] = NULL;
2335 continue;
2336 }
2337 if (!strcmp(argv[arg_i], "--tbytes")) {
2338 units_set_base(&unit_mode, UNITS_TBYTES);
2339 argv[arg_i] = NULL;
2340 continue;
2341 }
2342
2343 if (!df_mode)
2344 continue;
2345
2346 if (!strcmp(argv[arg_i], "-b")) {
2347 unit_mode = UNITS_RAW;
2348 argv[arg_i] = NULL;
2349 continue;
2350 }
2351 if (!strcmp(argv[arg_i], "-h")) {
2352 unit_mode = UNITS_HUMAN_BINARY;
2353 argv[arg_i] = NULL;
2354 continue;
2355 }
2356 if (!strcmp(argv[arg_i], "-H")) {
2357 unit_mode = UNITS_HUMAN_DECIMAL;
2358 argv[arg_i] = NULL;
2359 continue;
2360 }
2361 if (!strcmp(argv[arg_i], "-k")) {
2362 units_set_base(&unit_mode, UNITS_KBYTES);
2363 argv[arg_i] = NULL;
2364 continue;
2365 }
2366 if (!strcmp(argv[arg_i], "-m")) {
2367 units_set_base(&unit_mode, UNITS_MBYTES);
2368 argv[arg_i] = NULL;
2369 continue;
2370 }
2371 if (!strcmp(argv[arg_i], "-g")) {
2372 units_set_base(&unit_mode, UNITS_GBYTES);
2373 argv[arg_i] = NULL;
2374 continue;
2375 }
2376 if (!strcmp(argv[arg_i], "-t")) {
2377 units_set_base(&unit_mode, UNITS_TBYTES);
2378 argv[arg_i] = NULL;
2379 continue;
2380 }
2381 }
2382
2383 for (arg_i = 0, arg_end = 0; arg_i < *argc; arg_i++) {
2384 if (!argv[arg_i])
2385 continue;
2386 argv[arg_end] = argv[arg_i];
2387 arg_end++;
2388 }
2389
2390 *argc = arg_end;
2391
2392 return unit_mode;
2393 }
2394
2395 u64 div_factor(u64 num, int factor)
2396 {
2397 if (factor == 10)
2398 return num;
2399 num *= factor;
2400 num /= 10;
2401 return num;
2402 }
2403 /*
2404 * Get the length of the string converted from a u64 number.
2405 *
2406 * Result is equal to log10(num) + 1, but without the use of math library.
2407 */
2408 int count_digits(u64 num)
2409 {
2410 int ret = 0;
2411
2412 if (num == 0)
2413 return 1;
2414 while (num > 0) {
2415 ret++;
2416 num /= 10;
2417 }
2418 return ret;
2419 }
2420
2421 int string_is_numerical(const char *str)
2422 {
2423 if (!str)
2424 return 0;
2425 if (!(*str >= '0' && *str <= '9'))
2426 return 0;
2427 while (*str >= '0' && *str <= '9')
2428 str++;
2429 if (*str != '\0')
2430 return 0;
2431 return 1;
2432 }
2433
2434 int prefixcmp(const char *str, const char *prefix)
2435 {
2436 for (; ; str++, prefix++)
2437 if (!*prefix)
2438 return 0;
2439 else if (*str != *prefix)
2440 return (unsigned char)*prefix - (unsigned char)*str;
2441 }
2442
2443 /* Subvolume helper functions */
2444 /*
2445 * test if name is a correct subvolume name
2446 * this function return
2447 * 0-> name is not a correct subvolume name
2448 * 1-> name is a correct subvolume name
2449 */
2450 int test_issubvolname(const char *name)
2451 {
2452 return name[0] != '\0' && !strchr(name, '/') &&
2453 strcmp(name, ".") && strcmp(name, "..");
2454 }
2455
2456 /*
2457 * Test if path is a subvolume
2458 * Returns:
2459 * 0 - path exists but it is not a subvolume
2460 * 1 - path exists and it is a subvolume
2461 * < 0 - error
2462 */
2463 int test_issubvolume(const char *path)
2464 {
2465 struct stat st;
2466 struct statfs stfs;
2467 int res;
2468
2469 res = stat(path, &st);
2470 if (res < 0)
2471 return -errno;
2472
2473 if (st.st_ino != BTRFS_FIRST_FREE_OBJECTID || !S_ISDIR(st.st_mode))
2474 return 0;
2475
2476 res = statfs(path, &stfs);
2477 if (res < 0)
2478 return -errno;
2479
2480 return (int)stfs.f_type == BTRFS_SUPER_MAGIC;
2481 }
2482
2483 const char *subvol_strip_mountpoint(const char *mnt, const char *full_path)
2484 {
2485 int len = strlen(mnt);
2486 if (!len)
2487 return full_path;
2488
2489 if (mnt[len - 1] != '/')
2490 len += 1;
2491
2492 return full_path + len;
2493 }
2494
2495 /*
2496 * Returns
2497 * <0: Std error
2498 * 0: All fine
2499 * 1: Error; and error info printed to the terminal. Fixme.
2500 * 2: If the fullpath is root tree instead of subvol tree
2501 */
2502 int get_subvol_info(const char *fullpath, struct root_info *get_ri)
2503 {
2504 u64 sv_id;
2505 int ret = 1;
2506 int fd = -1;
2507 int mntfd = -1;
2508 char *mnt = NULL;
2509 const char *svpath = NULL;
2510 DIR *dirstream1 = NULL;
2511 DIR *dirstream2 = NULL;
2512
2513 ret = test_issubvolume(fullpath);
2514 if (ret < 0)
2515 return ret;
2516 if (!ret) {
2517 error("not a subvolume: %s", fullpath);
2518 return 1;
2519 }
2520
2521 ret = find_mount_root(fullpath, &mnt);
2522 if (ret < 0)
2523 return ret;
2524 if (ret > 0) {
2525 error("%s doesn't belong to btrfs mount point", fullpath);
2526 return 1;
2527 }
2528 ret = 1;
2529 svpath = subvol_strip_mountpoint(mnt, fullpath);
2530
2531 fd = btrfs_open_dir(fullpath, &dirstream1, 1);
2532 if (fd < 0)
2533 goto out;
2534
2535 ret = btrfs_list_get_path_rootid(fd, &sv_id);
2536 if (ret)
2537 goto out;
2538
2539 mntfd = btrfs_open_dir(mnt, &dirstream2, 1);
2540 if (mntfd < 0)
2541 goto out;
2542
2543 memset(get_ri, 0, sizeof(*get_ri));
2544 get_ri->root_id = sv_id;
2545
2546 if (sv_id == BTRFS_FS_TREE_OBJECTID)
2547 ret = btrfs_get_toplevel_subvol(mntfd, get_ri);
2548 else
2549 ret = btrfs_get_subvol(mntfd, get_ri);
2550 if (ret)
2551 error("can't find '%s': %d", svpath, ret);
2552
2553 out:
2554 close_file_or_dir(mntfd, dirstream2);
2555 close_file_or_dir(fd, dirstream1);
2556 free(mnt);
2557
2558 return ret;
2559 }
2560
2561 int get_subvol_info_by_rootid(const char *mnt, struct root_info *get_ri, u64 r_id)
2562 {
2563 int fd;
2564 int ret;
2565 DIR *dirstream = NULL;
2566
2567 fd = btrfs_open_dir(mnt, &dirstream, 1);
2568 if (fd < 0)
2569 return -EINVAL;
2570
2571 memset(get_ri, 0, sizeof(*get_ri));
2572 get_ri->root_id = r_id;
2573
2574 if (r_id == BTRFS_FS_TREE_OBJECTID)
2575 ret = btrfs_get_toplevel_subvol(fd, get_ri);
2576 else
2577 ret = btrfs_get_subvol(fd, get_ri);
2578
2579 if (ret)
2580 error("can't find rootid '%llu' on '%s': %d", r_id, mnt, ret);
2581
2582 close_file_or_dir(fd, dirstream);
2583
2584 return ret;
2585 }
2586
2587 int get_subvol_info_by_uuid(const char *mnt, struct root_info *get_ri, u8 *uuid_arg)
2588 {
2589 int fd;
2590 int ret;
2591 DIR *dirstream = NULL;
2592
2593 fd = btrfs_open_dir(mnt, &dirstream, 1);
2594 if (fd < 0)
2595 return -EINVAL;
2596
2597 memset(get_ri, 0, sizeof(*get_ri));
2598 uuid_copy(get_ri->uuid, uuid_arg);
2599
2600 ret = btrfs_get_subvol(fd, get_ri);
2601 if (ret) {
2602 char uuid_parsed[BTRFS_UUID_UNPARSED_SIZE];
2603 uuid_unparse(uuid_arg, uuid_parsed);
2604 error("can't find uuid '%s' on '%s': %d",
2605 uuid_parsed, mnt, ret);
2606 }
2607
2608 close_file_or_dir(fd, dirstream);
2609
2610 return ret;
2611 }
2612
2613 /* Set the seed manually */
2614 void init_rand_seed(u64 seed)
2615 {
2616 int i;
2617
2618 /* only use the last 48 bits */
2619 for (i = 0; i < 3; i++) {
2620 rand_seed[i] = (unsigned short)(seed ^ (unsigned short)(-1));
2621 seed >>= 16;
2622 }
2623 rand_seed_initlized = 1;
2624 }
2625
2626 static void __init_seed(void)
2627 {
2628 struct timeval tv;
2629 int ret;
2630 int fd;
2631
2632 if(rand_seed_initlized)
2633 return;
2634 /* Use urandom as primary seed source. */
2635 fd = open("/dev/urandom", O_RDONLY);
2636 if (fd >= 0) {
2637 ret = read(fd, rand_seed, sizeof(rand_seed));
2638 close(fd);
2639 if (ret < sizeof(rand_seed))
2640 goto fallback;
2641 } else {
2642 fallback:
2643 /* Use time and pid as fallback seed */
2644 warning("failed to read /dev/urandom, use time and pid as random seed");
2645 gettimeofday(&tv, 0);
2646 rand_seed[0] = getpid() ^ (tv.tv_sec & 0xFFFF);
2647 rand_seed[1] = getppid() ^ (tv.tv_usec & 0xFFFF);
2648 rand_seed[2] = (tv.tv_sec ^ tv.tv_usec) >> 16;
2649 }
2650 rand_seed_initlized = 1;
2651 }
2652
2653 u32 rand_u32(void)
2654 {
2655 __init_seed();
2656 /*
2657 * Don't use nrand48, its range is [0,2^31) The highest bit will alwasy
2658 * be 0. Use jrand48 to include the highest bit.
2659 */
2660 return (u32)jrand48(rand_seed);
2661 }
2662
2663 /* Return random number in range [0, upper) */
2664 unsigned int rand_range(unsigned int upper)
2665 {
2666 __init_seed();
2667 /*
2668 * Use the full 48bits to mod, which would be more uniformly
2669 * distributed
2670 */
2671 return (unsigned int)(jrand48(rand_seed) % upper);
2672 }
2673
2674 int rand_int(void)
2675 {
2676 return (int)(rand_u32());
2677 }
2678
2679 u64 rand_u64(void)
2680 {
2681 u64 ret = 0;
2682
2683 ret += rand_u32();
2684 ret <<= 32;
2685 ret += rand_u32();
2686 return ret;
2687 }
2688
2689 u16 rand_u16(void)
2690 {
2691 return (u16)(rand_u32());
2692 }
2693
2694 u8 rand_u8(void)
2695 {
2696 return (u8)(rand_u32());
2697 }
2698
2699 void btrfs_config_init(void)
2700 {
2701 }
2702
2703 /* Returns total size of main memory in bytes, -1UL if error. */
2704 unsigned long total_memory(void)
2705 {
2706 struct sysinfo si;
2707
2708 if (sysinfo(&si) < 0) {
2709 error("can't determine memory size");
2710 return -1UL;
2711 }
2712 return si.totalram * si.mem_unit; /* bytes */
2713 }
2714
2715 void print_device_info(struct btrfs_device *device, char *prefix)
2716 {
2717 if (prefix)
2718 printf("%s", prefix);
2719 printf("Device: id = %llu, name = %s\n",
2720 device->devid, device->name);
2721 }
2722
2723 void print_all_devices(struct list_head *devices)
2724 {
2725 struct btrfs_device *dev;
2726
2727 printf("All Devices:\n");
2728 list_for_each_entry(dev, devices, dev_list)
2729 print_device_info(dev, "\t");
2730 printf("\n");
2731 }
(deprecated) Btrfs progs developments and patch integration