2 * Copyright (C) 2007 Oracle. All rights reserved.
3 * Copyright (C) 2008 Morey Roof. All rights reserved.
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.
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.
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.
23 #include <sys/ioctl.h>
24 #include <sys/mount.h>
25 #include <sys/types.h>
27 #include <uuid/uuid.h>
32 #include <linux/loop.h>
33 #include <linux/major.h>
34 #include <linux/kdev_t.h>
36 #include <blkid/blkid.h>
38 #include <sys/statfs.h>
39 #include <linux/magic.h>
42 #include "kerncompat.h"
43 #include "radix-tree.h"
46 #include "transaction.h"
54 #define BLKDISCARD _IO(0x12,119)
57 static int btrfs_scan_done
= 0;
59 static char argv0_buf
[ARGV0_BUF_SIZE
] = "btrfs";
61 static int rand_seed_initlized
= 0;
62 static unsigned short rand_seed
[3];
64 const char *get_argv0_buf(void)
69 void fixup_argv0(char **argv
, const char *token
)
71 int len
= strlen(argv0_buf
);
73 snprintf(argv0_buf
+ len
, sizeof(argv0_buf
) - len
, " %s", token
);
77 void set_argv0(char **argv
)
79 strncpy(argv0_buf
, argv
[0], sizeof(argv0_buf
));
80 argv0_buf
[sizeof(argv0_buf
) - 1] = 0;
83 int check_argc_exact(int nargs
, int expected
)
86 fprintf(stderr
, "%s: too few arguments\n", argv0_buf
);
88 fprintf(stderr
, "%s: too many arguments\n", argv0_buf
);
90 return nargs
!= expected
;
93 int check_argc_min(int nargs
, int expected
)
95 if (nargs
< expected
) {
96 fprintf(stderr
, "%s: too few arguments\n", argv0_buf
);
103 int check_argc_max(int nargs
, int expected
)
105 if (nargs
> expected
) {
106 fprintf(stderr
, "%s: too many arguments\n", argv0_buf
);
115 * Discard the given range in one go
117 static int discard_range(int fd
, u64 start
, u64 len
)
119 u64 range
[2] = { start
, len
};
121 if (ioctl(fd
, BLKDISCARD
, &range
) < 0)
127 * Discard blocks in the given range in 1G chunks, the process is interruptible
129 static int discard_blocks(int fd
, u64 start
, u64 len
)
133 u64 chunk_size
= min_t(u64
, len
, 1*1024*1024*1024);
136 ret
= discard_range(fd
, start
, chunk_size
);
146 static u64 reference_root_table
[] = {
147 [1] = BTRFS_ROOT_TREE_OBJECTID
,
148 [2] = BTRFS_EXTENT_TREE_OBJECTID
,
149 [3] = BTRFS_CHUNK_TREE_OBJECTID
,
150 [4] = BTRFS_DEV_TREE_OBJECTID
,
151 [5] = BTRFS_FS_TREE_OBJECTID
,
152 [6] = BTRFS_CSUM_TREE_OBJECTID
,
155 int test_uuid_unique(char *fs_uuid
)
158 blkid_dev_iterate iter
= NULL
;
159 blkid_dev dev
= NULL
;
160 blkid_cache cache
= NULL
;
162 if (blkid_get_cache(&cache
, NULL
) < 0) {
163 printf("ERROR: lblkid cache get failed\n");
166 blkid_probe_all(cache
);
167 iter
= blkid_dev_iterate_begin(cache
);
168 blkid_dev_set_search(iter
, "UUID", fs_uuid
);
170 while (blkid_dev_next(iter
, &dev
) == 0) {
171 dev
= blkid_verify(cache
, dev
);
178 blkid_dev_iterate_end(iter
);
179 blkid_put_cache(cache
);
185 * Reserve space from free_tree.
186 * The algorithm is very simple, find the first cache_extent with enough space
187 * and allocate from its beginning.
189 static int reserve_free_space(struct cache_tree
*free_tree
, u64 len
,
192 struct cache_extent
*cache
;
196 cache
= first_cache_extent(free_tree
);
198 if (cache
->size
> len
) {
200 *ret_start
= cache
->start
;
203 if (cache
->size
== 0) {
204 remove_cache_extent(free_tree
, cache
);
211 cache
= next_cache_extent(cache
);
218 static inline int write_temp_super(int fd
, struct btrfs_super_block
*sb
,
224 crc
= btrfs_csum_data(NULL
, (char *)sb
+ BTRFS_CSUM_SIZE
, crc
,
225 BTRFS_SUPER_INFO_SIZE
- BTRFS_CSUM_SIZE
);
226 btrfs_csum_final(crc
, (char *)&sb
->csum
[0]);
227 ret
= pwrite(fd
, sb
, BTRFS_SUPER_INFO_SIZE
, sb_bytenr
);
228 if (ret
< BTRFS_SUPER_INFO_SIZE
)
229 ret
= (ret
< 0 ? -errno
: -EIO
);
236 * Setup temporary superblock at cfg->super_bynter
237 * Needed info are extracted from cfg, and root_bytenr, chunk_bytenr
239 * For now sys chunk array will be empty and dev_item is empty too.
240 * They will be re-initialized at temp chunk tree setup.
242 * The superblock signature is not valid, denotes a partially created
243 * filesystem, needs to be finalized.
245 static int setup_temp_super(int fd
, struct btrfs_mkfs_config
*cfg
,
246 u64 root_bytenr
, u64 chunk_bytenr
)
248 unsigned char chunk_uuid
[BTRFS_UUID_SIZE
];
249 char super_buf
[BTRFS_SUPER_INFO_SIZE
];
250 struct btrfs_super_block
*super
= (struct btrfs_super_block
*)super_buf
;
254 * We rely on cfg->chunk_uuid and cfg->fs_uuid to pass uuid
255 * for other functions.
256 * Caller must allocate space for them
258 BUG_ON(!cfg
->chunk_uuid
|| !cfg
->fs_uuid
);
259 memset(super_buf
, 0, BTRFS_SUPER_INFO_SIZE
);
260 cfg
->num_bytes
= round_down(cfg
->num_bytes
, cfg
->sectorsize
);
262 if (cfg
->fs_uuid
&& *cfg
->fs_uuid
) {
263 if (uuid_parse(cfg
->fs_uuid
, super
->fsid
) != 0) {
264 error("cound not parse UUID: %s", cfg
->fs_uuid
);
268 if (!test_uuid_unique(cfg
->fs_uuid
)) {
269 error("non-unique UUID: %s", cfg
->fs_uuid
);
274 uuid_generate(super
->fsid
);
275 uuid_unparse(super
->fsid
, cfg
->fs_uuid
);
277 uuid_generate(chunk_uuid
);
278 uuid_unparse(chunk_uuid
, cfg
->chunk_uuid
);
280 btrfs_set_super_bytenr(super
, cfg
->super_bytenr
);
281 btrfs_set_super_num_devices(super
, 1);
282 btrfs_set_super_magic(super
, BTRFS_MAGIC_PARTIAL
);
283 btrfs_set_super_generation(super
, 1);
284 btrfs_set_super_root(super
, root_bytenr
);
285 btrfs_set_super_chunk_root(super
, chunk_bytenr
);
286 btrfs_set_super_total_bytes(super
, cfg
->num_bytes
);
288 * Temporary filesystem will only have 6 tree roots:
289 * chunk tree, root tree, extent_tree, device tree, fs tree
292 btrfs_set_super_bytes_used(super
, 6 * cfg
->nodesize
);
293 btrfs_set_super_sectorsize(super
, cfg
->sectorsize
);
294 btrfs_set_super_leafsize(super
, cfg
->nodesize
);
295 btrfs_set_super_nodesize(super
, cfg
->nodesize
);
296 btrfs_set_super_stripesize(super
, cfg
->stripesize
);
297 btrfs_set_super_csum_type(super
, BTRFS_CSUM_TYPE_CRC32
);
298 btrfs_set_super_chunk_root(super
, chunk_bytenr
);
299 btrfs_set_super_cache_generation(super
, -1);
300 btrfs_set_super_incompat_flags(super
, cfg
->features
);
302 __strncpy_null(super
->label
, cfg
->label
, BTRFS_LABEL_SIZE
- 1);
304 /* Sys chunk array will be re-initialized at chunk tree init time */
305 super
->sys_chunk_array_size
= 0;
307 ret
= write_temp_super(fd
, super
, cfg
->super_bytenr
);
313 * Setup an extent buffer for tree block.
315 static int setup_temp_extent_buffer(struct extent_buffer
*buf
,
316 struct btrfs_mkfs_config
*cfg
,
317 u64 bytenr
, u64 owner
)
319 unsigned char fsid
[BTRFS_FSID_SIZE
];
320 unsigned char chunk_uuid
[BTRFS_UUID_SIZE
];
323 /* We rely on cfg->fs_uuid and chunk_uuid to fsid and chunk uuid */
324 BUG_ON(!cfg
->fs_uuid
|| !cfg
->chunk_uuid
);
325 ret
= uuid_parse(cfg
->fs_uuid
, fsid
);
328 ret
= uuid_parse(cfg
->chunk_uuid
, chunk_uuid
);
332 memset(buf
->data
, 0, cfg
->nodesize
);
333 buf
->len
= cfg
->nodesize
;
334 btrfs_set_header_bytenr(buf
, bytenr
);
335 btrfs_set_header_generation(buf
, 1);
336 btrfs_set_header_backref_rev(buf
, BTRFS_MIXED_BACKREF_REV
);
337 btrfs_set_header_owner(buf
, owner
);
338 btrfs_set_header_flags(buf
, BTRFS_HEADER_FLAG_WRITTEN
);
339 write_extent_buffer(buf
, chunk_uuid
, btrfs_header_chunk_tree_uuid(buf
),
341 write_extent_buffer(buf
, fsid
, btrfs_header_fsid(), BTRFS_FSID_SIZE
);
345 static inline int write_temp_extent_buffer(int fd
, struct extent_buffer
*buf
,
350 csum_tree_block_size(buf
, BTRFS_CRC32_SIZE
, 0);
352 /* Temporary extent buffer is always mapped 1:1 on disk */
353 ret
= pwrite(fd
, buf
->data
, buf
->len
, bytenr
);
355 ret
= (ret
< 0 ? ret
: -EIO
);
362 * Insert a root item for temporary tree root
364 * Only used in make_btrfs_v2().
366 static void insert_temp_root_item(struct extent_buffer
*buf
,
367 struct btrfs_mkfs_config
*cfg
,
368 int *slot
, u32
*itemoff
, u64 objectid
,
371 struct btrfs_root_item root_item
;
372 struct btrfs_inode_item
*inode_item
;
373 struct btrfs_disk_key disk_key
;
375 btrfs_set_header_nritems(buf
, *slot
+ 1);
376 (*itemoff
) -= sizeof(root_item
);
377 memset(&root_item
, 0, sizeof(root_item
));
378 inode_item
= &root_item
.inode
;
379 btrfs_set_stack_inode_generation(inode_item
, 1);
380 btrfs_set_stack_inode_size(inode_item
, 3);
381 btrfs_set_stack_inode_nlink(inode_item
, 1);
382 btrfs_set_stack_inode_nbytes(inode_item
, cfg
->nodesize
);
383 btrfs_set_stack_inode_mode(inode_item
, S_IFDIR
| 0755);
384 btrfs_set_root_refs(&root_item
, 1);
385 btrfs_set_root_used(&root_item
, cfg
->nodesize
);
386 btrfs_set_root_generation(&root_item
, 1);
387 btrfs_set_root_bytenr(&root_item
, bytenr
);
389 memset(&disk_key
, 0, sizeof(disk_key
));
390 btrfs_set_disk_key_type(&disk_key
, BTRFS_ROOT_ITEM_KEY
);
391 btrfs_set_disk_key_objectid(&disk_key
, objectid
);
392 btrfs_set_disk_key_offset(&disk_key
, 0);
394 btrfs_set_item_key(buf
, &disk_key
, *slot
);
395 btrfs_set_item_offset(buf
, btrfs_item_nr(*slot
), *itemoff
);
396 btrfs_set_item_size(buf
, btrfs_item_nr(*slot
), sizeof(root_item
));
397 write_extent_buffer(buf
, &root_item
,
398 btrfs_item_ptr_offset(buf
, *slot
),
403 static int setup_temp_root_tree(int fd
, struct btrfs_mkfs_config
*cfg
,
404 u64 root_bytenr
, u64 extent_bytenr
,
405 u64 dev_bytenr
, u64 fs_bytenr
, u64 csum_bytenr
)
407 struct extent_buffer
*buf
= NULL
;
408 u32 itemoff
= __BTRFS_LEAF_DATA_SIZE(cfg
->nodesize
);
413 * Provided bytenr must in ascending order, or tree root will have a
416 BUG_ON(!(root_bytenr
< extent_bytenr
&& extent_bytenr
< dev_bytenr
&&
417 dev_bytenr
< fs_bytenr
&& fs_bytenr
< csum_bytenr
));
418 buf
= malloc(sizeof(*buf
) + cfg
->nodesize
);
422 ret
= setup_temp_extent_buffer(buf
, cfg
, root_bytenr
,
423 BTRFS_ROOT_TREE_OBJECTID
);
427 insert_temp_root_item(buf
, cfg
, &slot
, &itemoff
,
428 BTRFS_EXTENT_TREE_OBJECTID
, extent_bytenr
);
429 insert_temp_root_item(buf
, cfg
, &slot
, &itemoff
,
430 BTRFS_DEV_TREE_OBJECTID
, dev_bytenr
);
431 insert_temp_root_item(buf
, cfg
, &slot
, &itemoff
,
432 BTRFS_FS_TREE_OBJECTID
, fs_bytenr
);
433 insert_temp_root_item(buf
, cfg
, &slot
, &itemoff
,
434 BTRFS_CSUM_TREE_OBJECTID
, csum_bytenr
);
436 ret
= write_temp_extent_buffer(fd
, buf
, root_bytenr
);
442 static int insert_temp_dev_item(int fd
, struct extent_buffer
*buf
,
443 struct btrfs_mkfs_config
*cfg
,
444 int *slot
, u32
*itemoff
)
446 struct btrfs_disk_key disk_key
;
447 struct btrfs_dev_item
*dev_item
;
448 char super_buf
[BTRFS_SUPER_INFO_SIZE
];
449 unsigned char dev_uuid
[BTRFS_UUID_SIZE
];
450 unsigned char fsid
[BTRFS_FSID_SIZE
];
451 struct btrfs_super_block
*super
= (struct btrfs_super_block
*)super_buf
;
454 ret
= pread(fd
, super_buf
, BTRFS_SUPER_INFO_SIZE
, cfg
->super_bytenr
);
455 if (ret
< BTRFS_SUPER_INFO_SIZE
) {
456 ret
= (ret
< 0 ? -errno
: -EIO
);
460 btrfs_set_header_nritems(buf
, *slot
+ 1);
461 (*itemoff
) -= sizeof(*dev_item
);
462 /* setup device item 1, 0 is for replace case */
463 btrfs_set_disk_key_type(&disk_key
, BTRFS_DEV_ITEM_KEY
);
464 btrfs_set_disk_key_objectid(&disk_key
, BTRFS_DEV_ITEMS_OBJECTID
);
465 btrfs_set_disk_key_offset(&disk_key
, 1);
466 btrfs_set_item_key(buf
, &disk_key
, *slot
);
467 btrfs_set_item_offset(buf
, btrfs_item_nr(*slot
), *itemoff
);
468 btrfs_set_item_size(buf
, btrfs_item_nr(*slot
), sizeof(*dev_item
));
470 dev_item
= btrfs_item_ptr(buf
, *slot
, struct btrfs_dev_item
);
471 /* Generate device uuid */
472 uuid_generate(dev_uuid
);
473 write_extent_buffer(buf
, dev_uuid
,
474 (unsigned long)btrfs_device_uuid(dev_item
),
476 uuid_parse(cfg
->fs_uuid
, fsid
);
477 write_extent_buffer(buf
, fsid
,
478 (unsigned long)btrfs_device_fsid(dev_item
),
480 btrfs_set_device_id(buf
, dev_item
, 1);
481 btrfs_set_device_generation(buf
, dev_item
, 0);
482 btrfs_set_device_total_bytes(buf
, dev_item
, cfg
->num_bytes
);
484 * The number must match the initial SYSTEM and META chunk size
486 btrfs_set_device_bytes_used(buf
, dev_item
,
487 BTRFS_MKFS_SYSTEM_GROUP_SIZE
+
488 BTRFS_CONVERT_META_GROUP_SIZE
);
489 btrfs_set_device_io_align(buf
, dev_item
, cfg
->sectorsize
);
490 btrfs_set_device_io_width(buf
, dev_item
, cfg
->sectorsize
);
491 btrfs_set_device_sector_size(buf
, dev_item
, cfg
->sectorsize
);
492 btrfs_set_device_type(buf
, dev_item
, 0);
494 /* Super dev_item is not complete, copy the complete one to sb */
495 read_extent_buffer(buf
, &super
->dev_item
, (unsigned long)dev_item
,
497 ret
= write_temp_super(fd
, super
, cfg
->super_bytenr
);
503 static int insert_temp_chunk_item(int fd
, struct extent_buffer
*buf
,
504 struct btrfs_mkfs_config
*cfg
,
505 int *slot
, u32
*itemoff
, u64 start
, u64 len
,
508 struct btrfs_chunk
*chunk
;
509 struct btrfs_disk_key disk_key
;
510 char super_buf
[BTRFS_SUPER_INFO_SIZE
];
511 struct btrfs_super_block
*sb
= (struct btrfs_super_block
*)super_buf
;
514 ret
= pread(fd
, super_buf
, BTRFS_SUPER_INFO_SIZE
,
516 if (ret
< BTRFS_SUPER_INFO_SIZE
) {
517 ret
= (ret
< 0 ? ret
: -EIO
);
521 btrfs_set_header_nritems(buf
, *slot
+ 1);
522 (*itemoff
) -= btrfs_chunk_item_size(1);
523 btrfs_set_disk_key_type(&disk_key
, BTRFS_CHUNK_ITEM_KEY
);
524 btrfs_set_disk_key_objectid(&disk_key
, BTRFS_FIRST_CHUNK_TREE_OBJECTID
);
525 btrfs_set_disk_key_offset(&disk_key
, start
);
526 btrfs_set_item_key(buf
, &disk_key
, *slot
);
527 btrfs_set_item_offset(buf
, btrfs_item_nr(*slot
), *itemoff
);
528 btrfs_set_item_size(buf
, btrfs_item_nr(*slot
),
529 btrfs_chunk_item_size(1));
531 chunk
= btrfs_item_ptr(buf
, *slot
, struct btrfs_chunk
);
532 btrfs_set_chunk_length(buf
, chunk
, len
);
533 btrfs_set_chunk_owner(buf
, chunk
, BTRFS_EXTENT_TREE_OBJECTID
);
534 btrfs_set_chunk_stripe_len(buf
, chunk
, 64 * 1024);
535 btrfs_set_chunk_type(buf
, chunk
, type
);
536 btrfs_set_chunk_io_align(buf
, chunk
, cfg
->sectorsize
);
537 btrfs_set_chunk_io_width(buf
, chunk
, cfg
->sectorsize
);
538 btrfs_set_chunk_sector_size(buf
, chunk
, cfg
->sectorsize
);
539 btrfs_set_chunk_num_stripes(buf
, chunk
, 1);
540 /* TODO: Support DUP profile for system chunk */
541 btrfs_set_stripe_devid_nr(buf
, chunk
, 0, 1);
542 /* We are doing 1:1 mapping, so start is its dev offset */
543 btrfs_set_stripe_offset_nr(buf
, chunk
, 0, start
);
544 write_extent_buffer(buf
, &sb
->dev_item
.uuid
,
545 (unsigned long)btrfs_stripe_dev_uuid_nr(chunk
, 0),
550 * If it's system chunk, also copy it to super block.
552 if (type
& BTRFS_BLOCK_GROUP_SYSTEM
) {
555 cur
= (char *)sb
->sys_chunk_array
+ sb
->sys_chunk_array_size
;
556 memcpy(cur
, &disk_key
, sizeof(disk_key
));
557 cur
+= sizeof(disk_key
);
558 read_extent_buffer(buf
, cur
, (unsigned long int)chunk
,
559 btrfs_chunk_item_size(1));
560 sb
->sys_chunk_array_size
+= btrfs_chunk_item_size(1) +
563 ret
= write_temp_super(fd
, sb
, cfg
->super_bytenr
);
568 static int setup_temp_chunk_tree(int fd
, struct btrfs_mkfs_config
*cfg
,
569 u64 sys_chunk_start
, u64 meta_chunk_start
,
572 struct extent_buffer
*buf
= NULL
;
573 u32 itemoff
= __BTRFS_LEAF_DATA_SIZE(cfg
->nodesize
);
577 /* Must ensure SYS chunk starts before META chunk */
578 BUG_ON(meta_chunk_start
< sys_chunk_start
);
579 buf
= malloc(sizeof(*buf
) + cfg
->nodesize
);
582 ret
= setup_temp_extent_buffer(buf
, cfg
, chunk_bytenr
,
583 BTRFS_CHUNK_TREE_OBJECTID
);
587 ret
= insert_temp_dev_item(fd
, buf
, cfg
, &slot
, &itemoff
);
590 ret
= insert_temp_chunk_item(fd
, buf
, cfg
, &slot
, &itemoff
,
592 BTRFS_MKFS_SYSTEM_GROUP_SIZE
,
593 BTRFS_BLOCK_GROUP_SYSTEM
);
596 ret
= insert_temp_chunk_item(fd
, buf
, cfg
, &slot
, &itemoff
,
598 BTRFS_CONVERT_META_GROUP_SIZE
,
599 BTRFS_BLOCK_GROUP_METADATA
);
602 ret
= write_temp_extent_buffer(fd
, buf
, chunk_bytenr
);
609 static void insert_temp_dev_extent(struct extent_buffer
*buf
,
610 int *slot
, u32
*itemoff
, u64 start
, u64 len
)
612 struct btrfs_dev_extent
*dev_extent
;
613 struct btrfs_disk_key disk_key
;
615 btrfs_set_header_nritems(buf
, *slot
+ 1);
616 (*itemoff
) -= sizeof(*dev_extent
);
617 btrfs_set_disk_key_type(&disk_key
, BTRFS_DEV_EXTENT_KEY
);
618 btrfs_set_disk_key_objectid(&disk_key
, 1);
619 btrfs_set_disk_key_offset(&disk_key
, start
);
620 btrfs_set_item_key(buf
, &disk_key
, *slot
);
621 btrfs_set_item_offset(buf
, btrfs_item_nr(*slot
), *itemoff
);
622 btrfs_set_item_size(buf
, btrfs_item_nr(*slot
), sizeof(*dev_extent
));
624 dev_extent
= btrfs_item_ptr(buf
, *slot
, struct btrfs_dev_extent
);
625 btrfs_set_dev_extent_chunk_objectid(buf
, dev_extent
,
626 BTRFS_FIRST_CHUNK_TREE_OBJECTID
);
627 btrfs_set_dev_extent_length(buf
, dev_extent
, len
);
628 btrfs_set_dev_extent_chunk_offset(buf
, dev_extent
, start
);
629 btrfs_set_dev_extent_chunk_tree(buf
, dev_extent
,
630 BTRFS_CHUNK_TREE_OBJECTID
);
634 static int setup_temp_dev_tree(int fd
, struct btrfs_mkfs_config
*cfg
,
635 u64 sys_chunk_start
, u64 meta_chunk_start
,
638 struct extent_buffer
*buf
= NULL
;
639 u32 itemoff
= __BTRFS_LEAF_DATA_SIZE(cfg
->nodesize
);
643 /* Must ensure SYS chunk starts before META chunk */
644 BUG_ON(meta_chunk_start
< sys_chunk_start
);
645 buf
= malloc(sizeof(*buf
) + cfg
->nodesize
);
648 ret
= setup_temp_extent_buffer(buf
, cfg
, dev_bytenr
,
649 BTRFS_DEV_TREE_OBJECTID
);
652 insert_temp_dev_extent(buf
, &slot
, &itemoff
, sys_chunk_start
,
653 BTRFS_MKFS_SYSTEM_GROUP_SIZE
);
654 insert_temp_dev_extent(buf
, &slot
, &itemoff
, meta_chunk_start
,
655 BTRFS_CONVERT_META_GROUP_SIZE
);
656 ret
= write_temp_extent_buffer(fd
, buf
, dev_bytenr
);
662 static int setup_temp_fs_tree(int fd
, struct btrfs_mkfs_config
*cfg
,
665 struct extent_buffer
*buf
= NULL
;
668 buf
= malloc(sizeof(*buf
) + cfg
->nodesize
);
671 ret
= setup_temp_extent_buffer(buf
, cfg
, fs_bytenr
,
672 BTRFS_FS_TREE_OBJECTID
);
676 * Temporary fs tree is completely empty.
678 ret
= write_temp_extent_buffer(fd
, buf
, fs_bytenr
);
684 static int setup_temp_csum_tree(int fd
, struct btrfs_mkfs_config
*cfg
,
687 struct extent_buffer
*buf
= NULL
;
690 buf
= malloc(sizeof(*buf
) + cfg
->nodesize
);
693 ret
= setup_temp_extent_buffer(buf
, cfg
, csum_bytenr
,
694 BTRFS_CSUM_TREE_OBJECTID
);
698 * Temporary csum tree is completely empty.
700 ret
= write_temp_extent_buffer(fd
, buf
, csum_bytenr
);
707 * Insert one temporary extent item.
709 * NOTE: if skinny_metadata is not enabled, this function must be called
710 * after all other trees are initialized.
711 * Or fs without skinny-metadata will be screwed up.
713 static int insert_temp_extent_item(int fd
, struct extent_buffer
*buf
,
714 struct btrfs_mkfs_config
*cfg
,
715 int *slot
, u32
*itemoff
, u64 bytenr
,
718 struct extent_buffer
*tmp
;
719 struct btrfs_extent_item
*ei
;
720 struct btrfs_extent_inline_ref
*iref
;
721 struct btrfs_disk_key disk_key
;
722 struct btrfs_disk_key tree_info_key
;
723 struct btrfs_tree_block_info
*info
;
725 int skinny_metadata
= cfg
->features
&
726 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA
;
730 itemsize
= sizeof(*ei
) + sizeof(*iref
);
732 itemsize
= sizeof(*ei
) + sizeof(*iref
) +
733 sizeof(struct btrfs_tree_block_info
);
735 btrfs_set_header_nritems(buf
, *slot
+ 1);
736 *(itemoff
) -= itemsize
;
738 if (skinny_metadata
) {
739 btrfs_set_disk_key_type(&disk_key
, BTRFS_METADATA_ITEM_KEY
);
740 btrfs_set_disk_key_offset(&disk_key
, 0);
742 btrfs_set_disk_key_type(&disk_key
, BTRFS_EXTENT_ITEM_KEY
);
743 btrfs_set_disk_key_offset(&disk_key
, cfg
->nodesize
);
745 btrfs_set_disk_key_objectid(&disk_key
, bytenr
);
747 btrfs_set_item_key(buf
, &disk_key
, *slot
);
748 btrfs_set_item_offset(buf
, btrfs_item_nr(*slot
), *itemoff
);
749 btrfs_set_item_size(buf
, btrfs_item_nr(*slot
), itemsize
);
751 ei
= btrfs_item_ptr(buf
, *slot
, struct btrfs_extent_item
);
752 btrfs_set_extent_refs(buf
, ei
, 1);
753 btrfs_set_extent_generation(buf
, ei
, 1);
754 btrfs_set_extent_flags(buf
, ei
, BTRFS_EXTENT_FLAG_TREE_BLOCK
);
756 if (skinny_metadata
) {
757 iref
= (struct btrfs_extent_inline_ref
*)(ei
+ 1);
759 info
= (struct btrfs_tree_block_info
*)(ei
+ 1);
760 iref
= (struct btrfs_extent_inline_ref
*)(info
+ 1);
762 btrfs_set_extent_inline_ref_type(buf
, iref
,
763 BTRFS_TREE_BLOCK_REF_KEY
);
764 btrfs_set_extent_inline_ref_offset(buf
, iref
, ref_root
);
771 * Lastly, check the tree block key by read the tree block
772 * Since we do 1:1 mapping for convert case, we can directly
773 * read the bytenr from disk
775 tmp
= malloc(sizeof(*tmp
) + cfg
->nodesize
);
778 ret
= setup_temp_extent_buffer(tmp
, cfg
, bytenr
, ref_root
);
781 ret
= pread(fd
, tmp
->data
, cfg
->nodesize
, bytenr
);
782 if (ret
< cfg
->nodesize
) {
783 ret
= (ret
< 0 ? -errno
: -EIO
);
786 if (btrfs_header_nritems(tmp
) == 0) {
787 btrfs_set_disk_key_type(&tree_info_key
, 0);
788 btrfs_set_disk_key_objectid(&tree_info_key
, 0);
789 btrfs_set_disk_key_offset(&tree_info_key
, 0);
791 btrfs_item_key(tmp
, &tree_info_key
, 0);
793 btrfs_set_tree_block_key(buf
, info
, &tree_info_key
);
800 static void insert_temp_block_group(struct extent_buffer
*buf
,
801 struct btrfs_mkfs_config
*cfg
,
802 int *slot
, u32
*itemoff
,
803 u64 bytenr
, u64 len
, u64 used
, u64 flag
)
805 struct btrfs_block_group_item bgi
;
806 struct btrfs_disk_key disk_key
;
808 btrfs_set_header_nritems(buf
, *slot
+ 1);
809 (*itemoff
) -= sizeof(bgi
);
810 btrfs_set_disk_key_type(&disk_key
, BTRFS_BLOCK_GROUP_ITEM_KEY
);
811 btrfs_set_disk_key_objectid(&disk_key
, bytenr
);
812 btrfs_set_disk_key_offset(&disk_key
, len
);
813 btrfs_set_item_key(buf
, &disk_key
, *slot
);
814 btrfs_set_item_offset(buf
, btrfs_item_nr(*slot
), *itemoff
);
815 btrfs_set_item_size(buf
, btrfs_item_nr(*slot
), sizeof(bgi
));
817 btrfs_set_block_group_flags(&bgi
, flag
);
818 btrfs_set_block_group_used(&bgi
, used
);
819 btrfs_set_block_group_chunk_objectid(&bgi
,
820 BTRFS_FIRST_CHUNK_TREE_OBJECTID
);
821 write_extent_buffer(buf
, &bgi
, btrfs_item_ptr_offset(buf
, *slot
),
826 static int setup_temp_extent_tree(int fd
, struct btrfs_mkfs_config
*cfg
,
827 u64 chunk_bytenr
, u64 root_bytenr
,
828 u64 extent_bytenr
, u64 dev_bytenr
,
829 u64 fs_bytenr
, u64 csum_bytenr
)
831 struct extent_buffer
*buf
= NULL
;
832 u32 itemoff
= __BTRFS_LEAF_DATA_SIZE(cfg
->nodesize
);
837 * We must ensure provided bytenr are in ascending order,
838 * or extent tree key order will be broken.
840 BUG_ON(!(chunk_bytenr
< root_bytenr
&& root_bytenr
< extent_bytenr
&&
841 extent_bytenr
< dev_bytenr
&& dev_bytenr
< fs_bytenr
&&
842 fs_bytenr
< csum_bytenr
));
843 buf
= malloc(sizeof(*buf
) + cfg
->nodesize
);
847 ret
= setup_temp_extent_buffer(buf
, cfg
, extent_bytenr
,
848 BTRFS_EXTENT_TREE_OBJECTID
);
852 ret
= insert_temp_extent_item(fd
, buf
, cfg
, &slot
, &itemoff
,
853 chunk_bytenr
, BTRFS_CHUNK_TREE_OBJECTID
);
857 insert_temp_block_group(buf
, cfg
, &slot
, &itemoff
, chunk_bytenr
,
858 BTRFS_MKFS_SYSTEM_GROUP_SIZE
, cfg
->nodesize
,
859 BTRFS_BLOCK_GROUP_SYSTEM
);
861 ret
= insert_temp_extent_item(fd
, buf
, cfg
, &slot
, &itemoff
,
862 root_bytenr
, BTRFS_ROOT_TREE_OBJECTID
);
866 /* 5 tree block used, root, extent, dev, fs and csum*/
867 insert_temp_block_group(buf
, cfg
, &slot
, &itemoff
, root_bytenr
,
868 BTRFS_CONVERT_META_GROUP_SIZE
, cfg
->nodesize
* 5,
869 BTRFS_BLOCK_GROUP_METADATA
);
871 ret
= insert_temp_extent_item(fd
, buf
, cfg
, &slot
, &itemoff
,
872 extent_bytenr
, BTRFS_EXTENT_TREE_OBJECTID
);
875 ret
= insert_temp_extent_item(fd
, buf
, cfg
, &slot
, &itemoff
,
876 dev_bytenr
, BTRFS_DEV_TREE_OBJECTID
);
879 ret
= insert_temp_extent_item(fd
, buf
, cfg
, &slot
, &itemoff
,
880 fs_bytenr
, BTRFS_FS_TREE_OBJECTID
);
883 ret
= insert_temp_extent_item(fd
, buf
, cfg
, &slot
, &itemoff
,
884 csum_bytenr
, BTRFS_CSUM_TREE_OBJECTID
);
888 ret
= write_temp_extent_buffer(fd
, buf
, extent_bytenr
);
895 * Improved version of make_btrfs().
898 * 1) Do chunk allocation to avoid used data
899 * And after this function, extent type matches chunk type
900 * 2) Better structured code
901 * No super long hand written codes to initialized all tree blocks
902 * Split into small blocks and reuse codes.
903 * TODO: Reuse tree operation facilities by introducing new flags
905 static int make_convert_btrfs(int fd
, struct btrfs_mkfs_config
*cfg
,
906 struct btrfs_convert_context
*cctx
)
908 struct cache_tree
*free
= &cctx
->free
;
909 struct cache_tree
*used
= &cctx
->used
;
911 u64 meta_chunk_start
;
912 /* chunk tree bytenr, in system chunk */
914 /* metadata trees bytenr, in metadata chunk */
922 /* Shouldn't happen */
923 BUG_ON(cache_tree_empty(used
));
926 * reserve space for temporary superblock first
927 * Here we allocate a little larger space, to keep later
928 * free space will be STRIPE_LEN aligned
930 ret
= reserve_free_space(free
, BTRFS_STRIPE_LEN
,
936 * Then reserve system chunk space
937 * TODO: Change system group size depending on cctx->total_bytes.
938 * If using current 4M, it can only handle less than one TB for
939 * worst case and then run out of sys space.
941 ret
= reserve_free_space(free
, BTRFS_MKFS_SYSTEM_GROUP_SIZE
,
945 ret
= reserve_free_space(free
, BTRFS_CONVERT_META_GROUP_SIZE
,
951 * Allocated meta/sys chunks will be mapped 1:1 with device offset.
953 * Inside the allocated metadata chunk, the layout will be:
954 * | offset | contents |
955 * -------------------------------------
957 * | +nodesize | extent root |
958 * | +nodesize * 2 | device root |
959 * | +nodesize * 3 | fs tree |
960 * | +nodesize * 4 | csum tree |
961 * -------------------------------------
962 * Inside the allocated system chunk, the layout will be:
963 * | offset | contents |
964 * -------------------------------------
965 * | +0 | chunk root |
966 * -------------------------------------
968 chunk_bytenr
= sys_chunk_start
;
969 root_bytenr
= meta_chunk_start
;
970 extent_bytenr
= meta_chunk_start
+ cfg
->nodesize
;
971 dev_bytenr
= meta_chunk_start
+ cfg
->nodesize
* 2;
972 fs_bytenr
= meta_chunk_start
+ cfg
->nodesize
* 3;
973 csum_bytenr
= meta_chunk_start
+ cfg
->nodesize
* 4;
975 ret
= setup_temp_super(fd
, cfg
, root_bytenr
, chunk_bytenr
);
979 ret
= setup_temp_root_tree(fd
, cfg
, root_bytenr
, extent_bytenr
,
980 dev_bytenr
, fs_bytenr
, csum_bytenr
);
983 ret
= setup_temp_chunk_tree(fd
, cfg
, sys_chunk_start
, meta_chunk_start
,
987 ret
= setup_temp_dev_tree(fd
, cfg
, sys_chunk_start
, meta_chunk_start
,
991 ret
= setup_temp_fs_tree(fd
, cfg
, fs_bytenr
);
994 ret
= setup_temp_csum_tree(fd
, cfg
, csum_bytenr
);
998 * Setup extent tree last, since it may need to read tree block key
999 * for non-skinny metadata case.
1001 ret
= setup_temp_extent_tree(fd
, cfg
, chunk_bytenr
, root_bytenr
,
1002 extent_bytenr
, dev_bytenr
, fs_bytenr
,
1009 * @fs_uuid - if NULL, generates a UUID, returns back the new filesystem UUID
1011 * The superblock signature is not valid, denotes a partially created
1012 * filesystem, needs to be finalized.
1014 int make_btrfs(int fd
, struct btrfs_mkfs_config
*cfg
,
1015 struct btrfs_convert_context
*cctx
)
1017 struct btrfs_super_block super
;
1018 struct extent_buffer
*buf
;
1019 struct btrfs_root_item root_item
;
1020 struct btrfs_disk_key disk_key
;
1021 struct btrfs_extent_item
*extent_item
;
1022 struct btrfs_inode_item
*inode_item
;
1023 struct btrfs_chunk
*chunk
;
1024 struct btrfs_dev_item
*dev_item
;
1025 struct btrfs_dev_extent
*dev_extent
;
1026 u8 chunk_tree_uuid
[BTRFS_UUID_SIZE
];
1036 int skinny_metadata
= !!(cfg
->features
&
1037 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA
);
1041 return make_convert_btrfs(fd
, cfg
, cctx
);
1042 buf
= malloc(sizeof(*buf
) + max(cfg
->sectorsize
, cfg
->nodesize
));
1046 first_free
= BTRFS_SUPER_INFO_OFFSET
+ cfg
->sectorsize
* 2 - 1;
1047 first_free
&= ~((u64
)cfg
->sectorsize
- 1);
1049 memset(&super
, 0, sizeof(super
));
1051 num_bytes
= (cfg
->num_bytes
/ cfg
->sectorsize
) * cfg
->sectorsize
;
1052 if (cfg
->fs_uuid
&& *cfg
->fs_uuid
) {
1053 if (uuid_parse(cfg
->fs_uuid
, super
.fsid
) != 0) {
1054 error("cannot not parse UUID: %s", cfg
->fs_uuid
);
1058 if (!test_uuid_unique(cfg
->fs_uuid
)) {
1059 error("non-unique UUID: %s", cfg
->fs_uuid
);
1064 uuid_generate(super
.fsid
);
1066 uuid_unparse(super
.fsid
, cfg
->fs_uuid
);
1068 uuid_generate(super
.dev_item
.uuid
);
1069 uuid_generate(chunk_tree_uuid
);
1071 btrfs_set_super_bytenr(&super
, cfg
->blocks
[0]);
1072 btrfs_set_super_num_devices(&super
, 1);
1073 btrfs_set_super_magic(&super
, BTRFS_MAGIC_PARTIAL
);
1074 btrfs_set_super_generation(&super
, 1);
1075 btrfs_set_super_root(&super
, cfg
->blocks
[1]);
1076 btrfs_set_super_chunk_root(&super
, cfg
->blocks
[3]);
1077 btrfs_set_super_total_bytes(&super
, num_bytes
);
1078 btrfs_set_super_bytes_used(&super
, 6 * cfg
->nodesize
);
1079 btrfs_set_super_sectorsize(&super
, cfg
->sectorsize
);
1080 btrfs_set_super_leafsize(&super
, cfg
->nodesize
);
1081 btrfs_set_super_nodesize(&super
, cfg
->nodesize
);
1082 btrfs_set_super_stripesize(&super
, cfg
->stripesize
);
1083 btrfs_set_super_csum_type(&super
, BTRFS_CSUM_TYPE_CRC32
);
1084 btrfs_set_super_chunk_root_generation(&super
, 1);
1085 btrfs_set_super_cache_generation(&super
, -1);
1086 btrfs_set_super_incompat_flags(&super
, cfg
->features
);
1088 __strncpy_null(super
.label
, cfg
->label
, BTRFS_LABEL_SIZE
- 1);
1090 /* create the tree of root objects */
1091 memset(buf
->data
, 0, cfg
->nodesize
);
1092 buf
->len
= cfg
->nodesize
;
1093 btrfs_set_header_bytenr(buf
, cfg
->blocks
[1]);
1094 btrfs_set_header_nritems(buf
, 4);
1095 btrfs_set_header_generation(buf
, 1);
1096 btrfs_set_header_backref_rev(buf
, BTRFS_MIXED_BACKREF_REV
);
1097 btrfs_set_header_owner(buf
, BTRFS_ROOT_TREE_OBJECTID
);
1098 write_extent_buffer(buf
, super
.fsid
, btrfs_header_fsid(),
1101 write_extent_buffer(buf
, chunk_tree_uuid
,
1102 btrfs_header_chunk_tree_uuid(buf
),
1105 /* create the items for the root tree */
1106 memset(&root_item
, 0, sizeof(root_item
));
1107 inode_item
= &root_item
.inode
;
1108 btrfs_set_stack_inode_generation(inode_item
, 1);
1109 btrfs_set_stack_inode_size(inode_item
, 3);
1110 btrfs_set_stack_inode_nlink(inode_item
, 1);
1111 btrfs_set_stack_inode_nbytes(inode_item
, cfg
->nodesize
);
1112 btrfs_set_stack_inode_mode(inode_item
, S_IFDIR
| 0755);
1113 btrfs_set_root_refs(&root_item
, 1);
1114 btrfs_set_root_used(&root_item
, cfg
->nodesize
);
1115 btrfs_set_root_generation(&root_item
, 1);
1117 memset(&disk_key
, 0, sizeof(disk_key
));
1118 btrfs_set_disk_key_type(&disk_key
, BTRFS_ROOT_ITEM_KEY
);
1119 btrfs_set_disk_key_offset(&disk_key
, 0);
1122 itemoff
= __BTRFS_LEAF_DATA_SIZE(cfg
->nodesize
) - sizeof(root_item
);
1123 btrfs_set_root_bytenr(&root_item
, cfg
->blocks
[2]);
1124 btrfs_set_disk_key_objectid(&disk_key
, BTRFS_EXTENT_TREE_OBJECTID
);
1125 btrfs_set_item_key(buf
, &disk_key
, nritems
);
1126 btrfs_set_item_offset(buf
, btrfs_item_nr(nritems
), itemoff
);
1127 btrfs_set_item_size(buf
, btrfs_item_nr(nritems
),
1129 write_extent_buffer(buf
, &root_item
, btrfs_item_ptr_offset(buf
,
1130 nritems
), sizeof(root_item
));
1133 itemoff
= itemoff
- sizeof(root_item
);
1134 btrfs_set_root_bytenr(&root_item
, cfg
->blocks
[4]);
1135 btrfs_set_disk_key_objectid(&disk_key
, BTRFS_DEV_TREE_OBJECTID
);
1136 btrfs_set_item_key(buf
, &disk_key
, nritems
);
1137 btrfs_set_item_offset(buf
, btrfs_item_nr(nritems
), itemoff
);
1138 btrfs_set_item_size(buf
, btrfs_item_nr(nritems
),
1140 write_extent_buffer(buf
, &root_item
,
1141 btrfs_item_ptr_offset(buf
, nritems
),
1145 itemoff
= itemoff
- sizeof(root_item
);
1146 btrfs_set_root_bytenr(&root_item
, cfg
->blocks
[5]);
1147 btrfs_set_disk_key_objectid(&disk_key
, BTRFS_FS_TREE_OBJECTID
);
1148 btrfs_set_item_key(buf
, &disk_key
, nritems
);
1149 btrfs_set_item_offset(buf
, btrfs_item_nr(nritems
), itemoff
);
1150 btrfs_set_item_size(buf
, btrfs_item_nr(nritems
),
1152 write_extent_buffer(buf
, &root_item
,
1153 btrfs_item_ptr_offset(buf
, nritems
),
1157 itemoff
= itemoff
- sizeof(root_item
);
1158 btrfs_set_root_bytenr(&root_item
, cfg
->blocks
[6]);
1159 btrfs_set_disk_key_objectid(&disk_key
, BTRFS_CSUM_TREE_OBJECTID
);
1160 btrfs_set_item_key(buf
, &disk_key
, nritems
);
1161 btrfs_set_item_offset(buf
, btrfs_item_nr(nritems
), itemoff
);
1162 btrfs_set_item_size(buf
, btrfs_item_nr(nritems
),
1164 write_extent_buffer(buf
, &root_item
,
1165 btrfs_item_ptr_offset(buf
, nritems
),
1170 csum_tree_block_size(buf
, BTRFS_CRC32_SIZE
, 0);
1171 ret
= pwrite(fd
, buf
->data
, cfg
->nodesize
, cfg
->blocks
[1]);
1172 if (ret
!= cfg
->nodesize
) {
1173 ret
= (ret
< 0 ? -errno
: -EIO
);
1177 /* create the items for the extent tree */
1178 memset(buf
->data
+ sizeof(struct btrfs_header
), 0,
1179 cfg
->nodesize
- sizeof(struct btrfs_header
));
1181 itemoff
= __BTRFS_LEAF_DATA_SIZE(cfg
->nodesize
);
1182 for (i
= 1; i
< 7; i
++) {
1183 item_size
= sizeof(struct btrfs_extent_item
);
1184 if (!skinny_metadata
)
1185 item_size
+= sizeof(struct btrfs_tree_block_info
);
1187 BUG_ON(cfg
->blocks
[i
] < first_free
);
1188 BUG_ON(cfg
->blocks
[i
] < cfg
->blocks
[i
- 1]);
1190 /* create extent item */
1191 itemoff
-= item_size
;
1192 btrfs_set_disk_key_objectid(&disk_key
, cfg
->blocks
[i
]);
1193 if (skinny_metadata
) {
1194 btrfs_set_disk_key_type(&disk_key
,
1195 BTRFS_METADATA_ITEM_KEY
);
1196 btrfs_set_disk_key_offset(&disk_key
, 0);
1198 btrfs_set_disk_key_type(&disk_key
,
1199 BTRFS_EXTENT_ITEM_KEY
);
1200 btrfs_set_disk_key_offset(&disk_key
, cfg
->nodesize
);
1202 btrfs_set_item_key(buf
, &disk_key
, nritems
);
1203 btrfs_set_item_offset(buf
, btrfs_item_nr(nritems
),
1205 btrfs_set_item_size(buf
, btrfs_item_nr(nritems
),
1207 extent_item
= btrfs_item_ptr(buf
, nritems
,
1208 struct btrfs_extent_item
);
1209 btrfs_set_extent_refs(buf
, extent_item
, 1);
1210 btrfs_set_extent_generation(buf
, extent_item
, 1);
1211 btrfs_set_extent_flags(buf
, extent_item
,
1212 BTRFS_EXTENT_FLAG_TREE_BLOCK
);
1215 /* create extent ref */
1216 ref_root
= reference_root_table
[i
];
1217 btrfs_set_disk_key_objectid(&disk_key
, cfg
->blocks
[i
]);
1218 btrfs_set_disk_key_offset(&disk_key
, ref_root
);
1219 btrfs_set_disk_key_type(&disk_key
, BTRFS_TREE_BLOCK_REF_KEY
);
1220 btrfs_set_item_key(buf
, &disk_key
, nritems
);
1221 btrfs_set_item_offset(buf
, btrfs_item_nr(nritems
),
1223 btrfs_set_item_size(buf
, btrfs_item_nr(nritems
), 0);
1226 btrfs_set_header_bytenr(buf
, cfg
->blocks
[2]);
1227 btrfs_set_header_owner(buf
, BTRFS_EXTENT_TREE_OBJECTID
);
1228 btrfs_set_header_nritems(buf
, nritems
);
1229 csum_tree_block_size(buf
, BTRFS_CRC32_SIZE
, 0);
1230 ret
= pwrite(fd
, buf
->data
, cfg
->nodesize
, cfg
->blocks
[2]);
1231 if (ret
!= cfg
->nodesize
) {
1232 ret
= (ret
< 0 ? -errno
: -EIO
);
1236 /* create the chunk tree */
1237 memset(buf
->data
+ sizeof(struct btrfs_header
), 0,
1238 cfg
->nodesize
- sizeof(struct btrfs_header
));
1240 item_size
= sizeof(*dev_item
);
1241 itemoff
= __BTRFS_LEAF_DATA_SIZE(cfg
->nodesize
) - item_size
;
1243 /* first device 1 (there is no device 0) */
1244 btrfs_set_disk_key_objectid(&disk_key
, BTRFS_DEV_ITEMS_OBJECTID
);
1245 btrfs_set_disk_key_offset(&disk_key
, 1);
1246 btrfs_set_disk_key_type(&disk_key
, BTRFS_DEV_ITEM_KEY
);
1247 btrfs_set_item_key(buf
, &disk_key
, nritems
);
1248 btrfs_set_item_offset(buf
, btrfs_item_nr(nritems
), itemoff
);
1249 btrfs_set_item_size(buf
, btrfs_item_nr(nritems
), item_size
);
1251 dev_item
= btrfs_item_ptr(buf
, nritems
, struct btrfs_dev_item
);
1252 btrfs_set_device_id(buf
, dev_item
, 1);
1253 btrfs_set_device_generation(buf
, dev_item
, 0);
1254 btrfs_set_device_total_bytes(buf
, dev_item
, num_bytes
);
1255 btrfs_set_device_bytes_used(buf
, dev_item
,
1256 BTRFS_MKFS_SYSTEM_GROUP_SIZE
);
1257 btrfs_set_device_io_align(buf
, dev_item
, cfg
->sectorsize
);
1258 btrfs_set_device_io_width(buf
, dev_item
, cfg
->sectorsize
);
1259 btrfs_set_device_sector_size(buf
, dev_item
, cfg
->sectorsize
);
1260 btrfs_set_device_type(buf
, dev_item
, 0);
1262 write_extent_buffer(buf
, super
.dev_item
.uuid
,
1263 (unsigned long)btrfs_device_uuid(dev_item
),
1265 write_extent_buffer(buf
, super
.fsid
,
1266 (unsigned long)btrfs_device_fsid(dev_item
),
1268 read_extent_buffer(buf
, &super
.dev_item
, (unsigned long)dev_item
,
1272 item_size
= btrfs_chunk_item_size(1);
1273 itemoff
= itemoff
- item_size
;
1275 /* then we have chunk 0 */
1276 btrfs_set_disk_key_objectid(&disk_key
, BTRFS_FIRST_CHUNK_TREE_OBJECTID
);
1277 btrfs_set_disk_key_offset(&disk_key
, 0);
1278 btrfs_set_disk_key_type(&disk_key
, BTRFS_CHUNK_ITEM_KEY
);
1279 btrfs_set_item_key(buf
, &disk_key
, nritems
);
1280 btrfs_set_item_offset(buf
, btrfs_item_nr(nritems
), itemoff
);
1281 btrfs_set_item_size(buf
, btrfs_item_nr(nritems
), item_size
);
1283 chunk
= btrfs_item_ptr(buf
, nritems
, struct btrfs_chunk
);
1284 btrfs_set_chunk_length(buf
, chunk
, BTRFS_MKFS_SYSTEM_GROUP_SIZE
);
1285 btrfs_set_chunk_owner(buf
, chunk
, BTRFS_EXTENT_TREE_OBJECTID
);
1286 btrfs_set_chunk_stripe_len(buf
, chunk
, 64 * 1024);
1287 btrfs_set_chunk_type(buf
, chunk
, BTRFS_BLOCK_GROUP_SYSTEM
);
1288 btrfs_set_chunk_io_align(buf
, chunk
, cfg
->sectorsize
);
1289 btrfs_set_chunk_io_width(buf
, chunk
, cfg
->sectorsize
);
1290 btrfs_set_chunk_sector_size(buf
, chunk
, cfg
->sectorsize
);
1291 btrfs_set_chunk_num_stripes(buf
, chunk
, 1);
1292 btrfs_set_stripe_devid_nr(buf
, chunk
, 0, 1);
1293 btrfs_set_stripe_offset_nr(buf
, chunk
, 0, 0);
1296 write_extent_buffer(buf
, super
.dev_item
.uuid
,
1297 (unsigned long)btrfs_stripe_dev_uuid(&chunk
->stripe
),
1300 /* copy the key for the chunk to the system array */
1301 ptr
= super
.sys_chunk_array
;
1302 array_size
= sizeof(disk_key
);
1304 memcpy(ptr
, &disk_key
, sizeof(disk_key
));
1305 ptr
+= sizeof(disk_key
);
1307 /* copy the chunk to the system array */
1308 read_extent_buffer(buf
, ptr
, (unsigned long)chunk
, item_size
);
1309 array_size
+= item_size
;
1311 btrfs_set_super_sys_array_size(&super
, array_size
);
1313 btrfs_set_header_bytenr(buf
, cfg
->blocks
[3]);
1314 btrfs_set_header_owner(buf
, BTRFS_CHUNK_TREE_OBJECTID
);
1315 btrfs_set_header_nritems(buf
, nritems
);
1316 csum_tree_block_size(buf
, BTRFS_CRC32_SIZE
, 0);
1317 ret
= pwrite(fd
, buf
->data
, cfg
->nodesize
, cfg
->blocks
[3]);
1318 if (ret
!= cfg
->nodesize
) {
1319 ret
= (ret
< 0 ? -errno
: -EIO
);
1323 /* create the device tree */
1324 memset(buf
->data
+ sizeof(struct btrfs_header
), 0,
1325 cfg
->nodesize
- sizeof(struct btrfs_header
));
1327 itemoff
= __BTRFS_LEAF_DATA_SIZE(cfg
->nodesize
) -
1328 sizeof(struct btrfs_dev_extent
);
1330 btrfs_set_disk_key_objectid(&disk_key
, 1);
1331 btrfs_set_disk_key_offset(&disk_key
, 0);
1332 btrfs_set_disk_key_type(&disk_key
, BTRFS_DEV_EXTENT_KEY
);
1333 btrfs_set_item_key(buf
, &disk_key
, nritems
);
1334 btrfs_set_item_offset(buf
, btrfs_item_nr(nritems
), itemoff
);
1335 btrfs_set_item_size(buf
, btrfs_item_nr(nritems
),
1336 sizeof(struct btrfs_dev_extent
));
1337 dev_extent
= btrfs_item_ptr(buf
, nritems
, struct btrfs_dev_extent
);
1338 btrfs_set_dev_extent_chunk_tree(buf
, dev_extent
,
1339 BTRFS_CHUNK_TREE_OBJECTID
);
1340 btrfs_set_dev_extent_chunk_objectid(buf
, dev_extent
,
1341 BTRFS_FIRST_CHUNK_TREE_OBJECTID
);
1342 btrfs_set_dev_extent_chunk_offset(buf
, dev_extent
, 0);
1344 write_extent_buffer(buf
, chunk_tree_uuid
,
1345 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(dev_extent
),
1348 btrfs_set_dev_extent_length(buf
, dev_extent
,
1349 BTRFS_MKFS_SYSTEM_GROUP_SIZE
);
1352 btrfs_set_header_bytenr(buf
, cfg
->blocks
[4]);
1353 btrfs_set_header_owner(buf
, BTRFS_DEV_TREE_OBJECTID
);
1354 btrfs_set_header_nritems(buf
, nritems
);
1355 csum_tree_block_size(buf
, BTRFS_CRC32_SIZE
, 0);
1356 ret
= pwrite(fd
, buf
->data
, cfg
->nodesize
, cfg
->blocks
[4]);
1357 if (ret
!= cfg
->nodesize
) {
1358 ret
= (ret
< 0 ? -errno
: -EIO
);
1362 /* create the FS root */
1363 memset(buf
->data
+ sizeof(struct btrfs_header
), 0,
1364 cfg
->nodesize
- sizeof(struct btrfs_header
));
1365 btrfs_set_header_bytenr(buf
, cfg
->blocks
[5]);
1366 btrfs_set_header_owner(buf
, BTRFS_FS_TREE_OBJECTID
);
1367 btrfs_set_header_nritems(buf
, 0);
1368 csum_tree_block_size(buf
, BTRFS_CRC32_SIZE
, 0);
1369 ret
= pwrite(fd
, buf
->data
, cfg
->nodesize
, cfg
->blocks
[5]);
1370 if (ret
!= cfg
->nodesize
) {
1371 ret
= (ret
< 0 ? -errno
: -EIO
);
1374 /* finally create the csum root */
1375 memset(buf
->data
+ sizeof(struct btrfs_header
), 0,
1376 cfg
->nodesize
- sizeof(struct btrfs_header
));
1377 btrfs_set_header_bytenr(buf
, cfg
->blocks
[6]);
1378 btrfs_set_header_owner(buf
, BTRFS_CSUM_TREE_OBJECTID
);
1379 btrfs_set_header_nritems(buf
, 0);
1380 csum_tree_block_size(buf
, BTRFS_CRC32_SIZE
, 0);
1381 ret
= pwrite(fd
, buf
->data
, cfg
->nodesize
, cfg
->blocks
[6]);
1382 if (ret
!= cfg
->nodesize
) {
1383 ret
= (ret
< 0 ? -errno
: -EIO
);
1387 /* and write out the super block */
1388 BUG_ON(sizeof(super
) > cfg
->sectorsize
);
1389 memset(buf
->data
, 0, BTRFS_SUPER_INFO_SIZE
);
1390 memcpy(buf
->data
, &super
, sizeof(super
));
1391 buf
->len
= BTRFS_SUPER_INFO_SIZE
;
1392 csum_tree_block_size(buf
, BTRFS_CRC32_SIZE
, 0);
1393 ret
= pwrite(fd
, buf
->data
, BTRFS_SUPER_INFO_SIZE
, cfg
->blocks
[0]);
1394 if (ret
!= BTRFS_SUPER_INFO_SIZE
) {
1395 ret
= (ret
< 0 ? -errno
: -EIO
);
1406 static const struct btrfs_fs_feature
{
1410 } mkfs_features
[] = {
1411 { "mixed-bg", BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS
,
1412 "mixed data and metadata block groups" },
1413 { "extref", BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF
,
1414 "increased hardlink limit per file to 65536" },
1415 { "raid56", BTRFS_FEATURE_INCOMPAT_RAID56
,
1416 "raid56 extended format" },
1417 { "skinny-metadata", BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA
,
1418 "reduced-size metadata extent refs" },
1419 { "no-holes", BTRFS_FEATURE_INCOMPAT_NO_HOLES
,
1420 "no explicit hole extents for files" },
1421 /* Keep this one last */
1422 { "list-all", BTRFS_FEATURE_LIST_ALL
, NULL
}
1425 static int parse_one_fs_feature(const char *name
, u64
*flags
)
1430 for (i
= 0; i
< ARRAY_SIZE(mkfs_features
); i
++) {
1431 if (name
[0] == '^' &&
1432 !strcmp(mkfs_features
[i
].name
, name
+ 1)) {
1433 *flags
&= ~ mkfs_features
[i
].flag
;
1435 } else if (!strcmp(mkfs_features
[i
].name
, name
)) {
1436 *flags
|= mkfs_features
[i
].flag
;
1444 void btrfs_parse_features_to_string(char *buf
, u64 flags
)
1450 for (i
= 0; i
< ARRAY_SIZE(mkfs_features
); i
++) {
1451 if (flags
& mkfs_features
[i
].flag
) {
1454 strcat(buf
, mkfs_features
[i
].name
);
1459 void btrfs_process_fs_features(u64 flags
)
1463 for (i
= 0; i
< ARRAY_SIZE(mkfs_features
); i
++) {
1464 if (flags
& mkfs_features
[i
].flag
) {
1465 printf("Turning ON incompat feature '%s': %s\n",
1466 mkfs_features
[i
].name
,
1467 mkfs_features
[i
].desc
);
1472 void btrfs_list_all_fs_features(u64 mask_disallowed
)
1476 fprintf(stderr
, "Filesystem features available:\n");
1477 for (i
= 0; i
< ARRAY_SIZE(mkfs_features
) - 1; i
++) {
1478 char *is_default
= "";
1480 if (mkfs_features
[i
].flag
& mask_disallowed
)
1482 if (mkfs_features
[i
].flag
& BTRFS_MKFS_DEFAULT_FEATURES
)
1483 is_default
= ", default";
1484 fprintf(stderr
, "%-20s- %s (0x%llx%s)\n",
1485 mkfs_features
[i
].name
,
1486 mkfs_features
[i
].desc
,
1487 mkfs_features
[i
].flag
,
1493 * Return NULL if all features were parsed fine, otherwise return the name of
1494 * the first unparsed.
1496 char* btrfs_parse_fs_features(char *namelist
, u64
*flags
)
1499 char *save_ptr
= NULL
; /* Satisfy static checkers */
1501 for (this_char
= strtok_r(namelist
, ",", &save_ptr
);
1503 this_char
= strtok_r(NULL
, ",", &save_ptr
)) {
1504 if (parse_one_fs_feature(this_char
, flags
))
1511 u64
btrfs_device_size(int fd
, struct stat
*st
)
1514 if (S_ISREG(st
->st_mode
)) {
1517 if (!S_ISBLK(st
->st_mode
)) {
1520 if (ioctl(fd
, BLKGETSIZE64
, &size
) >= 0) {
1526 static int zero_blocks(int fd
, off_t start
, size_t len
)
1528 char *buf
= malloc(len
);
1534 memset(buf
, 0, len
);
1535 written
= pwrite(fd
, buf
, len
, start
);
1542 #define ZERO_DEV_BYTES (2 * 1024 * 1024)
1544 /* don't write outside the device by clamping the region to the device size */
1545 static int zero_dev_clamped(int fd
, off_t start
, ssize_t len
, u64 dev_size
)
1547 off_t end
= max(start
, start
+ len
);
1550 /* and don't overwrite the disk labels on sparc */
1551 start
= max(start
, 1024);
1552 end
= max(end
, 1024);
1555 start
= min_t(u64
, start
, dev_size
);
1556 end
= min_t(u64
, end
, dev_size
);
1558 return zero_blocks(fd
, start
, end
- start
);
1561 int btrfs_add_to_fsid(struct btrfs_trans_handle
*trans
,
1562 struct btrfs_root
*root
, int fd
, char *path
,
1563 u64 device_total_bytes
, u32 io_width
, u32 io_align
,
1566 struct btrfs_super_block
*disk_super
;
1567 struct btrfs_super_block
*super
= root
->fs_info
->super_copy
;
1568 struct btrfs_device
*device
;
1569 struct btrfs_dev_item
*dev_item
;
1575 device_total_bytes
= (device_total_bytes
/ sectorsize
) * sectorsize
;
1577 device
= kzalloc(sizeof(*device
), GFP_NOFS
);
1580 buf
= kzalloc(sectorsize
, GFP_NOFS
);
1583 BUG_ON(sizeof(*disk_super
) > sectorsize
);
1585 disk_super
= (struct btrfs_super_block
*)buf
;
1586 dev_item
= &disk_super
->dev_item
;
1588 uuid_generate(device
->uuid
);
1591 device
->io_width
= io_width
;
1592 device
->io_align
= io_align
;
1593 device
->sector_size
= sectorsize
;
1595 device
->writeable
= 1;
1596 device
->total_bytes
= device_total_bytes
;
1597 device
->bytes_used
= 0;
1598 device
->total_ios
= 0;
1599 device
->dev_root
= root
->fs_info
->dev_root
;
1600 device
->name
= strdup(path
);
1604 INIT_LIST_HEAD(&device
->dev_list
);
1605 ret
= btrfs_add_device(trans
, root
, device
);
1608 fs_total_bytes
= btrfs_super_total_bytes(super
) + device_total_bytes
;
1609 btrfs_set_super_total_bytes(super
, fs_total_bytes
);
1611 num_devs
= btrfs_super_num_devices(super
) + 1;
1612 btrfs_set_super_num_devices(super
, num_devs
);
1614 memcpy(disk_super
, super
, sizeof(*disk_super
));
1616 btrfs_set_super_bytenr(disk_super
, BTRFS_SUPER_INFO_OFFSET
);
1617 btrfs_set_stack_device_id(dev_item
, device
->devid
);
1618 btrfs_set_stack_device_type(dev_item
, device
->type
);
1619 btrfs_set_stack_device_io_align(dev_item
, device
->io_align
);
1620 btrfs_set_stack_device_io_width(dev_item
, device
->io_width
);
1621 btrfs_set_stack_device_sector_size(dev_item
, device
->sector_size
);
1622 btrfs_set_stack_device_total_bytes(dev_item
, device
->total_bytes
);
1623 btrfs_set_stack_device_bytes_used(dev_item
, device
->bytes_used
);
1624 memcpy(&dev_item
->uuid
, device
->uuid
, BTRFS_UUID_SIZE
);
1626 ret
= pwrite(fd
, buf
, sectorsize
, BTRFS_SUPER_INFO_OFFSET
);
1627 BUG_ON(ret
!= sectorsize
);
1630 list_add(&device
->dev_list
, &root
->fs_info
->fs_devices
->devices
);
1631 device
->fs_devices
= root
->fs_info
->fs_devices
;
1640 static int btrfs_wipe_existing_sb(int fd
)
1642 const char *off
= NULL
;
1647 blkid_probe pr
= NULL
;
1649 pr
= blkid_new_probe();
1653 if (blkid_probe_set_device(pr
, fd
, 0, 0)) {
1658 ret
= blkid_probe_lookup_value(pr
, "SBMAGIC_OFFSET", &off
, NULL
);
1660 ret
= blkid_probe_lookup_value(pr
, "SBMAGIC", NULL
, &len
);
1662 if (ret
|| len
== 0 || off
== NULL
) {
1664 * If lookup fails, the probe did not find any values, eg. for
1665 * a file image or a loop device. Soft error.
1671 offset
= strtoll(off
, NULL
, 10);
1672 if (len
> sizeof(buf
))
1675 memset(buf
, 0, len
);
1676 ret
= pwrite(fd
, buf
, len
, offset
);
1678 error("cannot wipe existing superblock: %s", strerror(errno
));
1680 } else if (ret
!= len
) {
1681 error("cannot wipe existing superblock: wrote %d of %zd", ret
, len
);
1687 blkid_free_probe(pr
);
1691 int btrfs_prepare_device(int fd
, const char *file
, u64
*block_count_ret
,
1692 u64 max_block_count
, unsigned opflags
)
1698 ret
= fstat(fd
, &st
);
1700 error("unable to stat %s: %s", file
, strerror(errno
));
1704 block_count
= btrfs_device_size(fd
, &st
);
1705 if (block_count
== 0) {
1706 error("unable to determine size of %s", file
);
1709 if (max_block_count
)
1710 block_count
= min(block_count
, max_block_count
);
1712 if (opflags
& PREP_DEVICE_DISCARD
) {
1714 * We intentionally ignore errors from the discard ioctl. It
1715 * is not necessary for the mkfs functionality but just an
1718 if (discard_range(fd
, 0, 0) == 0) {
1719 if (opflags
& PREP_DEVICE_VERBOSE
)
1720 printf("Performing full device TRIM (%s) ...\n",
1721 pretty_size(block_count
));
1722 discard_blocks(fd
, 0, block_count
);
1726 ret
= zero_dev_clamped(fd
, 0, ZERO_DEV_BYTES
, block_count
);
1727 for (i
= 0 ; !ret
&& i
< BTRFS_SUPER_MIRROR_MAX
; i
++)
1728 ret
= zero_dev_clamped(fd
, btrfs_sb_offset(i
),
1729 BTRFS_SUPER_INFO_SIZE
, block_count
);
1730 if (!ret
&& (opflags
& PREP_DEVICE_ZERO_END
))
1731 ret
= zero_dev_clamped(fd
, block_count
- ZERO_DEV_BYTES
,
1732 ZERO_DEV_BYTES
, block_count
);
1735 error("failed to zero device '%s': %s", file
, strerror(-ret
));
1739 ret
= btrfs_wipe_existing_sb(fd
);
1741 error("cannot wipe superblocks on %s", file
);
1745 *block_count_ret
= block_count
;
1749 int btrfs_make_root_dir(struct btrfs_trans_handle
*trans
,
1750 struct btrfs_root
*root
, u64 objectid
)
1753 struct btrfs_inode_item inode_item
;
1754 time_t now
= time(NULL
);
1756 memset(&inode_item
, 0, sizeof(inode_item
));
1757 btrfs_set_stack_inode_generation(&inode_item
, trans
->transid
);
1758 btrfs_set_stack_inode_size(&inode_item
, 0);
1759 btrfs_set_stack_inode_nlink(&inode_item
, 1);
1760 btrfs_set_stack_inode_nbytes(&inode_item
, root
->nodesize
);
1761 btrfs_set_stack_inode_mode(&inode_item
, S_IFDIR
| 0755);
1762 btrfs_set_stack_timespec_sec(&inode_item
.atime
, now
);
1763 btrfs_set_stack_timespec_nsec(&inode_item
.atime
, 0);
1764 btrfs_set_stack_timespec_sec(&inode_item
.ctime
, now
);
1765 btrfs_set_stack_timespec_nsec(&inode_item
.ctime
, 0);
1766 btrfs_set_stack_timespec_sec(&inode_item
.mtime
, now
);
1767 btrfs_set_stack_timespec_nsec(&inode_item
.mtime
, 0);
1768 btrfs_set_stack_timespec_sec(&inode_item
.otime
, 0);
1769 btrfs_set_stack_timespec_nsec(&inode_item
.otime
, 0);
1771 if (root
->fs_info
->tree_root
== root
)
1772 btrfs_set_super_root_dir(root
->fs_info
->super_copy
, objectid
);
1774 ret
= btrfs_insert_inode(trans
, root
, objectid
, &inode_item
);
1778 ret
= btrfs_insert_inode_ref(trans
, root
, "..", 2, objectid
, objectid
, 0);
1782 btrfs_set_root_dirid(&root
->root_item
, objectid
);
1789 * checks if a path is a block device node
1790 * Returns negative errno on failure, otherwise
1791 * returns 1 for blockdev, 0 for not-blockdev
1793 int is_block_device(const char *path
)
1795 struct stat statbuf
;
1797 if (stat(path
, &statbuf
) < 0)
1800 return !!S_ISBLK(statbuf
.st_mode
);
1804 * check if given path is a mount point
1805 * return 1 if yes. 0 if no. -1 for error
1807 int is_mount_point(const char *path
)
1813 f
= setmntent("/proc/self/mounts", "r");
1817 while ((mnt
= getmntent(f
)) != NULL
) {
1818 if (strcmp(mnt
->mnt_dir
, path
))
1827 static int is_reg_file(const char *path
)
1829 struct stat statbuf
;
1831 if (stat(path
, &statbuf
) < 0)
1833 return S_ISREG(statbuf
.st_mode
);
1837 * This function checks if the given input parameter is
1839 * return <0 : some error in the given input
1840 * return BTRFS_ARG_UNKNOWN: unknown input
1841 * return BTRFS_ARG_UUID: given input is uuid
1842 * return BTRFS_ARG_MNTPOINT: given input is path
1843 * return BTRFS_ARG_REG: given input is regular file
1844 * return BTRFS_ARG_BLKDEV: given input is block device
1846 int check_arg_type(const char *input
)
1849 char path
[PATH_MAX
];
1854 if (realpath(input
, path
)) {
1855 if (is_block_device(path
) == 1)
1856 return BTRFS_ARG_BLKDEV
;
1858 if (is_mount_point(path
) == 1)
1859 return BTRFS_ARG_MNTPOINT
;
1861 if (is_reg_file(path
))
1862 return BTRFS_ARG_REG
;
1864 return BTRFS_ARG_UNKNOWN
;
1867 if (strlen(input
) == (BTRFS_UUID_UNPARSED_SIZE
- 1) &&
1868 !uuid_parse(input
, uuid
))
1869 return BTRFS_ARG_UUID
;
1871 return BTRFS_ARG_UNKNOWN
;
1875 * Find the mount point for a mounted device.
1876 * On success, returns 0 with mountpoint in *mp.
1877 * On failure, returns -errno (not mounted yields -EINVAL)
1878 * Is noisy on failures, expects to be given a mounted device.
1880 int get_btrfs_mount(const char *dev
, char *mp
, size_t mp_size
)
1885 ret
= is_block_device(dev
);
1888 error("not a block device: %s", dev
);
1891 error("cannot check %s: %s", dev
, strerror(-ret
));
1896 fd
= open(dev
, O_RDONLY
);
1899 error("cannot open %s: %s", dev
, strerror(errno
));
1903 ret
= check_mounted_where(fd
, dev
, mp
, mp_size
, NULL
);
1906 } else { /* mounted, all good */
1916 * Given a pathname, return a filehandle to:
1917 * the original pathname or,
1918 * if the pathname is a mounted btrfs device, to its mountpoint.
1920 * On error, return -1, errno should be set.
1922 int open_path_or_dev_mnt(const char *path
, DIR **dirstream
, int verbose
)
1927 if (is_block_device(path
)) {
1928 ret
= get_btrfs_mount(path
, mp
, sizeof(mp
));
1930 /* not a mounted btrfs dev */
1931 error_on(verbose
, "'%s' is not a mounted btrfs device",
1936 ret
= open_file_or_dir(mp
, dirstream
);
1937 error_on(verbose
&& ret
< 0, "can't access '%s': %s",
1938 path
, strerror(errno
));
1940 ret
= btrfs_open_dir(path
, dirstream
, 1);
1947 * Do the following checks before calling open_file_or_dir():
1948 * 1: path is in a btrfs filesystem
1949 * 2: path is a directory
1951 int btrfs_open_dir(const char *path
, DIR **dirstream
, int verbose
)
1957 if (statfs(path
, &stfs
) != 0) {
1958 error_on(verbose
, "cannot access '%s': %s", path
,
1963 if (stfs
.f_type
!= BTRFS_SUPER_MAGIC
) {
1964 error_on(verbose
, "not a btrfs filesystem: %s", path
);
1968 if (stat(path
, &st
) != 0) {
1969 error_on(verbose
, "cannot access '%s': %s", path
,
1974 if (!S_ISDIR(st
.st_mode
)) {
1975 error_on(verbose
, "not a directory: %s", path
);
1979 ret
= open_file_or_dir(path
, dirstream
);
1981 error_on(verbose
, "cannot access '%s': %s", path
,
1988 /* checks if a device is a loop device */
1989 static int is_loop_device (const char* device
) {
1990 struct stat statbuf
;
1992 if(stat(device
, &statbuf
) < 0)
1995 return (S_ISBLK(statbuf
.st_mode
) &&
1996 MAJOR(statbuf
.st_rdev
) == LOOP_MAJOR
);
2000 * Takes a loop device path (e.g. /dev/loop0) and returns
2001 * the associated file (e.g. /images/my_btrfs.img) using
2004 static int resolve_loop_device_with_loopdev(const char* loop_dev
, char* loop_file
)
2008 struct loop_info64 lo64
;
2010 fd
= open(loop_dev
, O_RDONLY
| O_NONBLOCK
);
2013 ret
= ioctl(fd
, LOOP_GET_STATUS64
, &lo64
);
2019 memcpy(loop_file
, lo64
.lo_file_name
, sizeof(lo64
.lo_file_name
));
2020 loop_file
[sizeof(lo64
.lo_file_name
)] = 0;
2028 /* Takes a loop device path (e.g. /dev/loop0) and returns
2029 * the associated file (e.g. /images/my_btrfs.img) */
2030 static int resolve_loop_device(const char* loop_dev
, char* loop_file
,
2037 char real_loop_dev
[PATH_MAX
];
2039 if (!realpath(loop_dev
, real_loop_dev
))
2041 snprintf(p
, PATH_MAX
, "/sys/block/%s/loop/backing_file", strrchr(real_loop_dev
, '/'));
2042 if (!(f
= fopen(p
, "r"))) {
2043 if (errno
== ENOENT
)
2045 * It's possibly a partitioned loop device, which is
2046 * resolvable with loopdev API.
2048 return resolve_loop_device_with_loopdev(loop_dev
, loop_file
);
2052 snprintf(fmt
, 20, "%%%i[^\n]", max_len
-1);
2053 ret
= fscanf(f
, fmt
, loop_file
);
2062 * Checks whether a and b are identical or device
2063 * files associated with the same block device
2065 static int is_same_blk_file(const char* a
, const char* b
)
2067 struct stat st_buf_a
, st_buf_b
;
2068 char real_a
[PATH_MAX
];
2069 char real_b
[PATH_MAX
];
2071 if (!realpath(a
, real_a
))
2072 strncpy_null(real_a
, a
);
2074 if (!realpath(b
, real_b
))
2075 strncpy_null(real_b
, b
);
2077 /* Identical path? */
2078 if (strcmp(real_a
, real_b
) == 0)
2081 if (stat(a
, &st_buf_a
) < 0 || stat(b
, &st_buf_b
) < 0) {
2082 if (errno
== ENOENT
)
2087 /* Same blockdevice? */
2088 if (S_ISBLK(st_buf_a
.st_mode
) && S_ISBLK(st_buf_b
.st_mode
) &&
2089 st_buf_a
.st_rdev
== st_buf_b
.st_rdev
) {
2094 if (st_buf_a
.st_dev
== st_buf_b
.st_dev
&&
2095 st_buf_a
.st_ino
== st_buf_b
.st_ino
) {
2102 /* checks if a and b are identical or device
2103 * files associated with the same block device or
2104 * if one file is a loop device that uses the other
2107 static int is_same_loop_file(const char* a
, const char* b
)
2109 char res_a
[PATH_MAX
];
2110 char res_b
[PATH_MAX
];
2111 const char* final_a
= NULL
;
2112 const char* final_b
= NULL
;
2115 /* Resolve a if it is a loop device */
2116 if((ret
= is_loop_device(a
)) < 0) {
2121 ret
= resolve_loop_device(a
, res_a
, sizeof(res_a
));
2132 /* Resolve b if it is a loop device */
2133 if ((ret
= is_loop_device(b
)) < 0) {
2138 ret
= resolve_loop_device(b
, res_b
, sizeof(res_b
));
2149 return is_same_blk_file(final_a
, final_b
);
2152 /* Checks if a file exists and is a block or regular file*/
2153 static int is_existing_blk_or_reg_file(const char* filename
)
2157 if(stat(filename
, &st_buf
) < 0) {
2164 return (S_ISBLK(st_buf
.st_mode
) || S_ISREG(st_buf
.st_mode
));
2167 /* Checks if a file is used (directly or indirectly via a loop device)
2168 * by a device in fs_devices
2170 static int blk_file_in_dev_list(struct btrfs_fs_devices
* fs_devices
,
2174 struct list_head
*head
;
2175 struct list_head
*cur
;
2176 struct btrfs_device
*device
;
2178 head
= &fs_devices
->devices
;
2179 list_for_each(cur
, head
) {
2180 device
= list_entry(cur
, struct btrfs_device
, dev_list
);
2182 if((ret
= is_same_loop_file(device
->name
, file
)))
2190 * Resolve a pathname to a device mapper node to /dev/mapper/<name>
2191 * Returns NULL on invalid input or malloc failure; Other failures
2192 * will be handled by the caller using the input pathame.
2194 char *canonicalize_dm_name(const char *ptname
)
2198 char path
[PATH_MAX
], name
[PATH_MAX
], *res
= NULL
;
2200 if (!ptname
|| !*ptname
)
2203 snprintf(path
, sizeof(path
), "/sys/block/%s/dm/name", ptname
);
2204 if (!(f
= fopen(path
, "r")))
2207 /* read <name>\n from sysfs */
2208 if (fgets(name
, sizeof(name
), f
) && (sz
= strlen(name
)) > 1) {
2209 name
[sz
- 1] = '\0';
2210 snprintf(path
, sizeof(path
), "/dev/mapper/%s", name
);
2212 if (access(path
, F_OK
) == 0)
2220 * Resolve a pathname to a canonical device node, e.g. /dev/sda1 or
2221 * to a device mapper pathname.
2222 * Returns NULL on invalid input or malloc failure; Other failures
2223 * will be handled by the caller using the input pathame.
2225 char *canonicalize_path(const char *path
)
2227 char *canonical
, *p
;
2229 if (!path
|| !*path
)
2232 canonical
= realpath(path
, NULL
);
2234 return strdup(path
);
2235 p
= strrchr(canonical
, '/');
2236 if (p
&& strncmp(p
, "/dm-", 4) == 0 && isdigit(*(p
+ 4))) {
2237 char *dm
= canonicalize_dm_name(p
+ 1);
2248 * returns 1 if the device was mounted, < 0 on error or 0 if everything
2249 * is safe to continue.
2251 int check_mounted(const char* file
)
2256 fd
= open(file
, O_RDONLY
);
2258 error("mount check: cannot open %s: %s", file
,
2263 ret
= check_mounted_where(fd
, file
, NULL
, 0, NULL
);
2269 int check_mounted_where(int fd
, const char *file
, char *where
, int size
,
2270 struct btrfs_fs_devices
**fs_dev_ret
)
2275 struct btrfs_fs_devices
*fs_devices_mnt
= NULL
;
2279 /* scan the initial device */
2280 ret
= btrfs_scan_one_device(fd
, file
, &fs_devices_mnt
,
2281 &total_devs
, BTRFS_SUPER_INFO_OFFSET
, SBREAD_DEFAULT
);
2282 is_btrfs
= (ret
>= 0);
2284 /* scan other devices */
2285 if (is_btrfs
&& total_devs
> 1) {
2286 ret
= btrfs_scan_lblkid();
2291 /* iterate over the list of currently mounted filesystems */
2292 if ((f
= setmntent ("/proc/self/mounts", "r")) == NULL
)
2295 while ((mnt
= getmntent (f
)) != NULL
) {
2297 if(strcmp(mnt
->mnt_type
, "btrfs") != 0)
2300 ret
= blk_file_in_dev_list(fs_devices_mnt
, mnt
->mnt_fsname
);
2302 /* ignore entries in the mount table that are not
2303 associated with a file*/
2304 if((ret
= is_existing_blk_or_reg_file(mnt
->mnt_fsname
)) < 0)
2305 goto out_mntloop_err
;
2309 ret
= is_same_loop_file(file
, mnt
->mnt_fsname
);
2313 goto out_mntloop_err
;
2318 /* Did we find an entry in mnt table? */
2319 if (mnt
&& size
&& where
) {
2320 strncpy(where
, mnt
->mnt_dir
, size
);
2324 *fs_dev_ret
= fs_devices_mnt
;
2326 ret
= (mnt
!= NULL
);
2334 struct pending_dir
{
2335 struct list_head list
;
2336 char name
[PATH_MAX
];
2339 int btrfs_register_one_device(const char *fname
)
2341 struct btrfs_ioctl_vol_args args
;
2345 fd
= open("/dev/btrfs-control", O_RDWR
);
2348 "failed to open /dev/btrfs-control, skipping device registration: %s",
2352 memset(&args
, 0, sizeof(args
));
2353 strncpy_null(args
.name
, fname
);
2354 ret
= ioctl(fd
, BTRFS_IOC_SCAN_DEV
, &args
);
2356 error("device scan failed on '%s': %s", fname
,
2365 * Register all devices in the fs_uuid list created in the user
2366 * space. Ensure btrfs_scan_lblkid() is called before this func.
2368 int btrfs_register_all_devices(void)
2372 struct btrfs_fs_devices
*fs_devices
;
2373 struct btrfs_device
*device
;
2374 struct list_head
*all_uuids
;
2376 all_uuids
= btrfs_scanned_uuids();
2378 list_for_each_entry(fs_devices
, all_uuids
, list
) {
2379 list_for_each_entry(device
, &fs_devices
->devices
, dev_list
) {
2381 err
= btrfs_register_one_device(device
->name
);
2391 int btrfs_device_already_in_root(struct btrfs_root
*root
, int fd
,
2394 struct btrfs_super_block
*disk_super
;
2398 buf
= malloc(BTRFS_SUPER_INFO_SIZE
);
2403 ret
= pread(fd
, buf
, BTRFS_SUPER_INFO_SIZE
, super_offset
);
2404 if (ret
!= BTRFS_SUPER_INFO_SIZE
)
2408 disk_super
= (struct btrfs_super_block
*)buf
;
2410 * Accept devices from the same filesystem, allow partially created
2413 if (btrfs_super_magic(disk_super
) != BTRFS_MAGIC
&&
2414 btrfs_super_magic(disk_super
) != BTRFS_MAGIC_PARTIAL
)
2417 if (!memcmp(disk_super
->fsid
, root
->fs_info
->super_copy
->fsid
,
2427 * Note: this function uses a static per-thread buffer. Do not call this
2428 * function more than 10 times within one argument list!
2430 const char *pretty_size_mode(u64 size
, unsigned mode
)
2432 static __thread
int ps_index
= 0;
2433 static __thread
char ps_array
[10][32];
2436 ret
= ps_array
[ps_index
];
2439 (void)pretty_size_snprintf(size
, ret
, 32, mode
);
2444 static const char* unit_suffix_binary
[] =
2445 { "B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"};
2446 static const char* unit_suffix_decimal
[] =
2447 { "B", "kB", "MB", "GB", "TB", "PB", "EB"};
2449 int pretty_size_snprintf(u64 size
, char *str
, size_t str_size
, unsigned unit_mode
)
2455 const char** suffix
= NULL
;
2461 if ((unit_mode
& ~UNITS_MODE_MASK
) == UNITS_RAW
) {
2462 snprintf(str
, str_size
, "%llu", size
);
2466 if ((unit_mode
& ~UNITS_MODE_MASK
) == UNITS_BINARY
) {
2469 suffix
= unit_suffix_binary
;
2470 } else if ((unit_mode
& ~UNITS_MODE_MASK
) == UNITS_DECIMAL
) {
2473 suffix
= unit_suffix_decimal
;
2478 fprintf(stderr
, "INTERNAL ERROR: unknown unit base, mode %d\n",
2486 switch (unit_mode
& UNITS_MODE_MASK
) {
2487 case UNITS_TBYTES
: base
*= mult
; num_divs
++;
2488 case UNITS_GBYTES
: base
*= mult
; num_divs
++;
2489 case UNITS_MBYTES
: base
*= mult
; num_divs
++;
2490 case UNITS_KBYTES
: num_divs
++;
2497 while (size
>= mult
) {
2503 * If the value is smaller than base, we didn't do any
2504 * division, in that case, base should be 1, not original
2505 * base, or the unit will be wrong
2511 if (num_divs
>= ARRAY_SIZE(unit_suffix_binary
)) {
2513 printf("INTERNAL ERROR: unsupported unit suffix, index %d\n",
2518 fraction
= (float)last_size
/ base
;
2520 return snprintf(str
, str_size
, "%.2f%s", fraction
, suffix
[num_divs
]);
2524 * __strncpy_null - strncpy with null termination
2525 * @dest: the target array
2526 * @src: the source string
2527 * @n: maximum bytes to copy (size of *dest)
2529 * Like strncpy, but ensures destination is null-terminated.
2531 * Copies the string pointed to by src, including the terminating null
2532 * byte ('\0'), to the buffer pointed to by dest, up to a maximum
2533 * of n bytes. Then ensure that dest is null-terminated.
2535 char *__strncpy_null(char *dest
, const char *src
, size_t n
)
2537 strncpy(dest
, src
, n
);
2544 * Checks to make sure that the label matches our requirements.
2546 0 if everything is safe and usable
2547 -1 if the label is too long
2549 static int check_label(const char *input
)
2551 int len
= strlen(input
);
2553 if (len
> BTRFS_LABEL_SIZE
- 1) {
2554 error("label %s is too long (max %d)", input
,
2555 BTRFS_LABEL_SIZE
- 1);
2562 static int set_label_unmounted(const char *dev
, const char *label
)
2564 struct btrfs_trans_handle
*trans
;
2565 struct btrfs_root
*root
;
2568 ret
= check_mounted(dev
);
2570 error("checking mount status of %s failed: %d", dev
, ret
);
2574 error("device %s is mounted, use mount point", dev
);
2578 /* Open the super_block at the default location
2579 * and as read-write.
2581 root
= open_ctree(dev
, 0, OPEN_CTREE_WRITES
);
2582 if (!root
) /* errors are printed by open_ctree() */
2585 trans
= btrfs_start_transaction(root
, 1);
2586 __strncpy_null(root
->fs_info
->super_copy
->label
, label
, BTRFS_LABEL_SIZE
- 1);
2588 btrfs_commit_transaction(trans
, root
);
2590 /* Now we close it since we are done. */
2595 static int set_label_mounted(const char *mount_path
, const char *labelp
)
2598 char label
[BTRFS_LABEL_SIZE
];
2600 fd
= open(mount_path
, O_RDONLY
| O_NOATIME
);
2602 error("unable to access %s: %s", mount_path
, strerror(errno
));
2606 memset(label
, 0, sizeof(label
));
2607 __strncpy_null(label
, labelp
, BTRFS_LABEL_SIZE
- 1);
2608 if (ioctl(fd
, BTRFS_IOC_SET_FSLABEL
, label
) < 0) {
2609 error("unable to set label of %s: %s", mount_path
,
2619 int get_label_unmounted(const char *dev
, char *label
)
2621 struct btrfs_root
*root
;
2624 ret
= check_mounted(dev
);
2626 error("checking mount status of %s failed: %d", dev
, ret
);
2630 /* Open the super_block at the default location
2633 root
= open_ctree(dev
, 0, 0);
2637 __strncpy_null(label
, root
->fs_info
->super_copy
->label
,
2638 BTRFS_LABEL_SIZE
- 1);
2640 /* Now we close it since we are done. */
2646 * If a partition is mounted, try to get the filesystem label via its
2647 * mounted path rather than device. Return the corresponding error
2648 * the user specified the device path.
2650 int get_label_mounted(const char *mount_path
, char *labelp
)
2652 char label
[BTRFS_LABEL_SIZE
];
2656 fd
= open(mount_path
, O_RDONLY
| O_NOATIME
);
2658 error("unable to access %s: %s", mount_path
, strerror(errno
));
2662 memset(label
, '\0', sizeof(label
));
2663 ret
= ioctl(fd
, BTRFS_IOC_GET_FSLABEL
, label
);
2665 if (errno
!= ENOTTY
)
2666 error("unable to get label of %s: %s", mount_path
,
2673 __strncpy_null(labelp
, label
, BTRFS_LABEL_SIZE
- 1);
2678 int get_label(const char *btrfs_dev
, char *label
)
2682 ret
= is_existing_blk_or_reg_file(btrfs_dev
);
2684 ret
= get_label_mounted(btrfs_dev
, label
);
2686 ret
= get_label_unmounted(btrfs_dev
, label
);
2691 int set_label(const char *btrfs_dev
, const char *label
)
2695 if (check_label(label
))
2698 ret
= is_existing_blk_or_reg_file(btrfs_dev
);
2700 ret
= set_label_mounted(btrfs_dev
, label
);
2702 ret
= set_label_unmounted(btrfs_dev
, label
);
2708 * A not-so-good version fls64. No fascinating optimization since
2709 * no one except parse_size use it
2711 static int fls64(u64 x
)
2715 for (i
= 0; i
<64; i
++)
2716 if (x
<< i
& (1ULL << 63))
2721 u64
parse_size(char *s
)
2729 error("size value is empty");
2733 error("size value '%s' is less equal than 0", s
);
2736 ret
= strtoull(s
, &endptr
, 10);
2738 error("size value '%s' is invalid", s
);
2741 if (endptr
[0] && endptr
[1]) {
2742 error("illegal suffix contains character '%c' in wrong position",
2747 * strtoll returns LLONG_MAX when overflow, if this happens,
2748 * need to call strtoull to get the real size
2750 if (errno
== ERANGE
&& ret
== ULLONG_MAX
) {
2751 error("size value '%s' is too large for u64", s
);
2755 c
= tolower(endptr
[0]);
2778 error("unknown size descriptor '%c'", c
);
2782 /* Check whether ret * mult overflow */
2783 if (fls64(ret
) + fls64(mult
) - 1 > 64) {
2784 error("size value '%s' is too large for u64", s
);
2791 u64
parse_qgroupid(const char *p
)
2793 char *s
= strchr(p
, '/');
2794 const char *ptr_src_end
= p
+ strlen(p
);
2795 char *ptr_parse_end
= NULL
;
2804 /* Numeric format like '0/257' is the primary case */
2806 id
= strtoull(p
, &ptr_parse_end
, 10);
2807 if (ptr_parse_end
!= ptr_src_end
)
2811 level
= strtoull(p
, &ptr_parse_end
, 10);
2812 if (ptr_parse_end
!= s
)
2815 id
= strtoull(s
+ 1, &ptr_parse_end
, 10);
2816 if (ptr_parse_end
!= ptr_src_end
)
2819 return (level
<< BTRFS_QGROUP_LEVEL_SHIFT
) | id
;
2822 /* Path format like subv at 'my_subvol' is the fallback case */
2823 ret
= test_issubvolume(p
);
2824 if (ret
< 0 || !ret
)
2826 fd
= open(p
, O_RDONLY
);
2829 ret
= lookup_ino_rootid(fd
, &id
);
2831 error("failed to lookup root id: %s", strerror(-ret
));
2838 error("invalid qgroupid or subvolume path: %s", p
);
2842 int open_file_or_dir3(const char *fname
, DIR **dirstream
, int open_flags
)
2848 ret
= stat(fname
, &st
);
2852 if (S_ISDIR(st
.st_mode
)) {
2853 *dirstream
= opendir(fname
);
2856 fd
= dirfd(*dirstream
);
2857 } else if (S_ISREG(st
.st_mode
) || S_ISLNK(st
.st_mode
)) {
2858 fd
= open(fname
, open_flags
);
2861 * we set this on purpose, in case the caller output
2862 * strerror(errno) as success
2870 closedir(*dirstream
);
2877 int open_file_or_dir(const char *fname
, DIR **dirstream
)
2879 return open_file_or_dir3(fname
, dirstream
, O_RDWR
);
2882 void close_file_or_dir(int fd
, DIR *dirstream
)
2885 closedir(dirstream
);
2890 int get_device_info(int fd
, u64 devid
,
2891 struct btrfs_ioctl_dev_info_args
*di_args
)
2895 di_args
->devid
= devid
;
2896 memset(&di_args
->uuid
, '\0', sizeof(di_args
->uuid
));
2898 ret
= ioctl(fd
, BTRFS_IOC_DEV_INFO
, di_args
);
2899 return ret
< 0 ? -errno
: 0;
2902 static u64
find_max_device_id(struct btrfs_ioctl_search_args
*search_args
,
2905 struct btrfs_dev_item
*dev_item
;
2906 char *buf
= search_args
->buf
;
2908 buf
+= (nr_items
- 1) * (sizeof(struct btrfs_ioctl_search_header
)
2909 + sizeof(struct btrfs_dev_item
));
2910 buf
+= sizeof(struct btrfs_ioctl_search_header
);
2912 dev_item
= (struct btrfs_dev_item
*)buf
;
2914 return btrfs_stack_device_id(dev_item
);
2917 static int search_chunk_tree_for_fs_info(int fd
,
2918 struct btrfs_ioctl_fs_info_args
*fi_args
)
2922 u64 start_devid
= 1;
2923 struct btrfs_ioctl_search_args search_args
;
2924 struct btrfs_ioctl_search_key
*search_key
= &search_args
.key
;
2926 fi_args
->num_devices
= 0;
2928 max_items
= BTRFS_SEARCH_ARGS_BUFSIZE
2929 / (sizeof(struct btrfs_ioctl_search_header
)
2930 + sizeof(struct btrfs_dev_item
));
2932 search_key
->tree_id
= BTRFS_CHUNK_TREE_OBJECTID
;
2933 search_key
->min_objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
2934 search_key
->max_objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
2935 search_key
->min_type
= BTRFS_DEV_ITEM_KEY
;
2936 search_key
->max_type
= BTRFS_DEV_ITEM_KEY
;
2937 search_key
->min_transid
= 0;
2938 search_key
->max_transid
= (u64
)-1;
2939 search_key
->nr_items
= max_items
;
2940 search_key
->max_offset
= (u64
)-1;
2943 search_key
->min_offset
= start_devid
;
2945 ret
= ioctl(fd
, BTRFS_IOC_TREE_SEARCH
, &search_args
);
2949 fi_args
->num_devices
+= (u64
)search_key
->nr_items
;
2951 if (search_key
->nr_items
== max_items
) {
2952 start_devid
= find_max_device_id(&search_args
,
2953 search_key
->nr_items
) + 1;
2957 /* get the lastest max_id to stay consistent with the num_devices */
2958 if (search_key
->nr_items
== 0)
2960 * last tree_search returns an empty buf, use the devid of
2961 * the last dev_item of the previous tree_search
2963 fi_args
->max_id
= start_devid
- 1;
2965 fi_args
->max_id
= find_max_device_id(&search_args
,
2966 search_key
->nr_items
);
2972 * For a given path, fill in the ioctl fs_ and info_ args.
2973 * If the path is a btrfs mountpoint, fill info for all devices.
2974 * If the path is a btrfs device, fill in only that device.
2976 * The path provided must be either on a mounted btrfs fs,
2977 * or be a mounted btrfs device.
2979 * Returns 0 on success, or a negative errno.
2981 int get_fs_info(char *path
, struct btrfs_ioctl_fs_info_args
*fi_args
,
2982 struct btrfs_ioctl_dev_info_args
**di_ret
)
2989 struct btrfs_fs_devices
*fs_devices_mnt
= NULL
;
2990 struct btrfs_ioctl_dev_info_args
*di_args
;
2991 struct btrfs_ioctl_dev_info_args tmp
;
2993 DIR *dirstream
= NULL
;
2995 memset(fi_args
, 0, sizeof(*fi_args
));
2997 if (is_block_device(path
) == 1) {
2998 struct btrfs_super_block
*disk_super
;
2999 char buf
[BTRFS_SUPER_INFO_SIZE
];
3002 /* Ensure it's mounted, then set path to the mountpoint */
3003 fd
= open(path
, O_RDONLY
);
3006 error("cannot open %s: %s", path
, strerror(errno
));
3009 ret
= check_mounted_where(fd
, path
, mp
, sizeof(mp
),
3018 /* Only fill in this one device */
3019 fi_args
->num_devices
= 1;
3021 disk_super
= (struct btrfs_super_block
*)buf
;
3022 ret
= btrfs_read_dev_super(fd
, disk_super
,
3023 BTRFS_SUPER_INFO_OFFSET
, 0);
3028 devid
= btrfs_stack_device_id(&disk_super
->dev_item
);
3030 fi_args
->max_id
= devid
;
3033 memcpy(fi_args
->fsid
, fs_devices_mnt
->fsid
, BTRFS_FSID_SIZE
);
3037 /* at this point path must not be for a block device */
3038 fd
= open_file_or_dir(path
, &dirstream
);
3044 /* fill in fi_args if not just a single device */
3045 if (fi_args
->num_devices
!= 1) {
3046 ret
= ioctl(fd
, BTRFS_IOC_FS_INFO
, fi_args
);
3053 * The fs_args->num_devices does not include seed devices
3055 ret
= search_chunk_tree_for_fs_info(fd
, fi_args
);
3060 * search_chunk_tree_for_fs_info() will lacks the devid 0
3061 * so manual probe for it here.
3063 ret
= get_device_info(fd
, 0, &tmp
);
3065 fi_args
->num_devices
++;
3073 if (!fi_args
->num_devices
)
3076 di_args
= *di_ret
= malloc((fi_args
->num_devices
) * sizeof(*di_args
));
3083 memcpy(di_args
, &tmp
, sizeof(tmp
));
3084 for (; i
<= fi_args
->max_id
; ++i
) {
3085 ret
= get_device_info(fd
, i
, &di_args
[ndevs
]);
3094 * only when the only dev we wanted to find is not there then
3095 * let any error be returned
3097 if (fi_args
->num_devices
!= 1) {
3103 close_file_or_dir(fd
, dirstream
);
3107 #define isoctal(c) (((c) & ~7) == '0')
3109 static inline void translate(char *f
, char *t
)
3111 while (*f
!= '\0') {
3113 isoctal(f
[1]) && isoctal(f
[2]) && isoctal(f
[3])) {
3114 *t
++ = 64*(f
[1] & 7) + 8*(f
[2] & 7) + (f
[3] & 7);
3124 * Checks if the swap device.
3125 * Returns 1 if swap device, < 0 on error or 0 if not swap device.
3127 static int is_swap_device(const char *file
)
3138 if (stat(file
, &st_buf
) < 0)
3140 if (S_ISBLK(st_buf
.st_mode
))
3141 dev
= st_buf
.st_rdev
;
3142 else if (S_ISREG(st_buf
.st_mode
)) {
3143 dev
= st_buf
.st_dev
;
3144 ino
= st_buf
.st_ino
;
3148 if ((f
= fopen("/proc/swaps", "r")) == NULL
)
3151 /* skip the first line */
3152 if (fgets(tmp
, sizeof(tmp
), f
) == NULL
)
3155 while (fgets(tmp
, sizeof(tmp
), f
) != NULL
) {
3156 if ((cp
= strchr(tmp
, ' ')) != NULL
)
3158 if ((cp
= strchr(tmp
, '\t')) != NULL
)
3160 translate(tmp
, buf
);
3161 if (stat(buf
, &st_buf
) != 0)
3163 if (S_ISBLK(st_buf
.st_mode
)) {
3164 if (dev
== st_buf
.st_rdev
) {
3168 } else if (S_ISREG(st_buf
.st_mode
)) {
3169 if (dev
== st_buf
.st_dev
&& ino
== st_buf
.st_ino
) {
3183 * Check for existing filesystem or partition table on device.
3185 * 1 for existing fs or partition
3186 * 0 for nothing found
3187 * -1 for internal error
3189 static int check_overwrite(const char *device
)
3192 blkid_probe pr
= NULL
;
3196 if (!device
|| !*device
)
3199 ret
= -1; /* will reset on success of all setup calls */
3201 pr
= blkid_new_probe_from_filename(device
);
3205 size
= blkid_probe_get_size(pr
);
3209 /* nothing to overwrite on a 0-length device */
3215 ret
= blkid_probe_enable_partitions(pr
, 1);
3219 ret
= blkid_do_fullprobe(pr
);
3224 * Blkid returns 1 for nothing found and 0 when it finds a signature,
3225 * but we want the exact opposite, so reverse the return value here.
3227 * In addition print some useful diagnostics about what actually is
3235 if (!blkid_probe_lookup_value(pr
, "TYPE", &type
, NULL
)) {
3237 "%s appears to contain an existing "
3238 "filesystem (%s).\n", device
, type
);
3239 } else if (!blkid_probe_lookup_value(pr
, "PTTYPE", &type
, NULL
)) {
3241 "%s appears to contain a partition "
3242 "table (%s).\n", device
, type
);
3245 "%s appears to contain something weird "
3246 "according to blkid\n", device
);
3252 blkid_free_probe(pr
);
3255 "probe of %s failed, cannot detect "
3256 "existing filesystem.\n", device
);
3260 static int group_profile_devs_min(u64 flag
)
3262 switch (flag
& BTRFS_BLOCK_GROUP_PROFILE_MASK
) {
3263 case 0: /* single */
3264 case BTRFS_BLOCK_GROUP_DUP
:
3266 case BTRFS_BLOCK_GROUP_RAID0
:
3267 case BTRFS_BLOCK_GROUP_RAID1
:
3268 case BTRFS_BLOCK_GROUP_RAID5
:
3270 case BTRFS_BLOCK_GROUP_RAID6
:
3272 case BTRFS_BLOCK_GROUP_RAID10
:
3279 int test_num_disk_vs_raid(u64 metadata_profile
, u64 data_profile
,
3280 u64 dev_cnt
, int mixed
, int ssd
)
3287 allowed
|= BTRFS_BLOCK_GROUP_RAID10
;
3289 allowed
|= BTRFS_BLOCK_GROUP_RAID6
;
3291 allowed
|= BTRFS_BLOCK_GROUP_RAID0
| BTRFS_BLOCK_GROUP_RAID1
|
3292 BTRFS_BLOCK_GROUP_RAID5
;
3294 allowed
|= BTRFS_BLOCK_GROUP_DUP
;
3298 ((metadata_profile
| data_profile
) & BTRFS_BLOCK_GROUP_DUP
)) {
3299 warning("DUP is not recommended on filesystem with multiple devices");
3301 if (metadata_profile
& ~allowed
) {
3303 "ERROR: unable to create FS with metadata profile %s "
3304 "(have %llu devices but %d devices are required)\n",
3305 btrfs_group_profile_str(metadata_profile
), dev_cnt
,
3306 group_profile_devs_min(metadata_profile
));
3309 if (data_profile
& ~allowed
) {
3311 "ERROR: unable to create FS with data profile %s "
3312 "(have %llu devices but %d devices are required)\n",
3313 btrfs_group_profile_str(data_profile
), dev_cnt
,
3314 group_profile_devs_min(data_profile
));
3318 warning_on(!mixed
&& (data_profile
& BTRFS_BLOCK_GROUP_DUP
) && ssd
,
3319 "DUP may not actually lead to 2 copies on the device, see manual page");
3324 int group_profile_max_safe_loss(u64 flags
)
3326 switch (flags
& BTRFS_BLOCK_GROUP_PROFILE_MASK
) {
3327 case 0: /* single */
3328 case BTRFS_BLOCK_GROUP_DUP
:
3329 case BTRFS_BLOCK_GROUP_RAID0
:
3331 case BTRFS_BLOCK_GROUP_RAID1
:
3332 case BTRFS_BLOCK_GROUP_RAID5
:
3333 case BTRFS_BLOCK_GROUP_RAID10
:
3335 case BTRFS_BLOCK_GROUP_RAID6
:
3343 * Check if a device is suitable for btrfs
3345 * 1: something is wrong, an error is printed
3348 int test_dev_for_mkfs(const char *file
, int force_overwrite
)
3353 ret
= is_swap_device(file
);
3355 error("checking status of %s: %s", file
, strerror(-ret
));
3359 error("%s is a swap device", file
);
3362 if (!force_overwrite
) {
3363 if (check_overwrite(file
)) {
3364 error("use the -f option to force overwrite of %s",
3369 ret
= check_mounted(file
);
3371 error("cannot check mount status of %s: %s", file
,
3376 error("%s is mounted", file
);
3379 /* check if the device is busy */
3380 fd
= open(file
, O_RDWR
|O_EXCL
);
3382 error("unable to open %s: %s", file
, strerror(errno
));
3385 if (fstat(fd
, &st
)) {
3386 error("unable to stat %s: %s", file
, strerror(errno
));
3390 if (!S_ISBLK(st
.st_mode
)) {
3391 error("%s is not a block device", file
);
3399 int btrfs_scan_lblkid(void)
3404 struct btrfs_fs_devices
*tmp_devices
;
3405 blkid_dev_iterate iter
= NULL
;
3406 blkid_dev dev
= NULL
;
3407 blkid_cache cache
= NULL
;
3408 char path
[PATH_MAX
];
3410 if (btrfs_scan_done
)
3413 if (blkid_get_cache(&cache
, NULL
) < 0) {
3414 error("blkid cache get failed");
3417 blkid_probe_all(cache
);
3418 iter
= blkid_dev_iterate_begin(cache
);
3419 blkid_dev_set_search(iter
, "TYPE", "btrfs");
3420 while (blkid_dev_next(iter
, &dev
) == 0) {
3421 dev
= blkid_verify(cache
, dev
);
3424 /* if we are here its definitely a btrfs disk*/
3425 strncpy_null(path
, blkid_dev_devname(dev
));
3427 fd
= open(path
, O_RDONLY
);
3429 error("cannot open %s: %s", path
, strerror(errno
));
3432 ret
= btrfs_scan_one_device(fd
, path
, &tmp_devices
,
3433 &num_devices
, BTRFS_SUPER_INFO_OFFSET
,
3436 error("cannot scan %s: %s", path
, strerror(-ret
));
3443 blkid_dev_iterate_end(iter
);
3444 blkid_put_cache(cache
);
3446 btrfs_scan_done
= 1;
3451 int is_vol_small(const char *file
)
3458 fd
= open(file
, O_RDONLY
);
3461 if (fstat(fd
, &st
) < 0) {
3466 size
= btrfs_device_size(fd
, &st
);
3471 if (size
< BTRFS_MKFS_SMALL_VOLUME_SIZE
) {
3481 * This reads a line from the stdin and only returns non-zero if the
3482 * first whitespace delimited token is a case insensitive match with yes
3485 int ask_user(const char *question
)
3487 char buf
[30] = {0,};
3488 char *saveptr
= NULL
;
3491 printf("%s [y/N]: ", question
);
3493 return fgets(buf
, sizeof(buf
) - 1, stdin
) &&
3494 (answer
= strtok_r(buf
, " \t\n\r", &saveptr
)) &&
3495 (!strcasecmp(answer
, "yes") || !strcasecmp(answer
, "y"));
3500 * - file or directory return the containing tree root id
3501 * - subvolume return its own tree id
3502 * - BTRFS_EMPTY_SUBVOL_DIR_OBJECTID (directory with ino == 2) the result is
3503 * undefined and function returns -1
3505 int lookup_ino_rootid(int fd
, u64
*rootid
)
3507 struct btrfs_ioctl_ino_lookup_args args
;
3510 memset(&args
, 0, sizeof(args
));
3512 args
.objectid
= BTRFS_FIRST_FREE_OBJECTID
;
3514 ret
= ioctl(fd
, BTRFS_IOC_INO_LOOKUP
, &args
);
3518 *rootid
= args
.treeid
;
3524 * return 0 if a btrfs mount point is found
3525 * return 1 if a mount point is found but not btrfs
3526 * return <0 if something goes wrong
3528 int find_mount_root(const char *path
, char **mount_root
)
3536 int longest_matchlen
= 0;
3537 char *longest_match
= NULL
;
3539 fd
= open(path
, O_RDONLY
| O_NOATIME
);
3544 mnttab
= setmntent("/proc/self/mounts", "r");
3548 while ((ent
= getmntent(mnttab
))) {
3549 len
= strlen(ent
->mnt_dir
);
3550 if (strncmp(ent
->mnt_dir
, path
, len
) == 0) {
3551 /* match found and use the latest match */
3552 if (longest_matchlen
<= len
) {
3553 free(longest_match
);
3554 longest_matchlen
= len
;
3555 longest_match
= strdup(ent
->mnt_dir
);
3556 not_btrfs
= strcmp(ent
->mnt_type
, "btrfs");
3565 free(longest_match
);
3570 *mount_root
= realpath(longest_match
, NULL
);
3574 free(longest_match
);
3578 int test_minimum_size(const char *file
, u32 nodesize
)
3581 struct stat statbuf
;
3583 fd
= open(file
, O_RDONLY
);
3586 if (stat(file
, &statbuf
) < 0) {
3590 if (btrfs_device_size(fd
, &statbuf
) < btrfs_min_dev_size(nodesize
)) {
3600 * Test if path is a directory
3602 * 0 - path exists but it is not a directory
3603 * 1 - path exists and it is a directory
3606 int test_isdir(const char *path
)
3611 ret
= stat(path
, &st
);
3615 return !!S_ISDIR(st
.st_mode
);
3618 void units_set_mode(unsigned *units
, unsigned mode
)
3620 unsigned base
= *units
& UNITS_MODE_MASK
;
3622 *units
= base
| mode
;
3625 void units_set_base(unsigned *units
, unsigned base
)
3627 unsigned mode
= *units
& ~UNITS_MODE_MASK
;
3629 *units
= base
| mode
;
3632 int find_next_key(struct btrfs_path
*path
, struct btrfs_key
*key
)
3636 for (level
= 0; level
< BTRFS_MAX_LEVEL
; level
++) {
3637 if (!path
->nodes
[level
])
3639 if (path
->slots
[level
] + 1 >=
3640 btrfs_header_nritems(path
->nodes
[level
]))
3643 btrfs_item_key_to_cpu(path
->nodes
[level
], key
,
3644 path
->slots
[level
] + 1);
3646 btrfs_node_key_to_cpu(path
->nodes
[level
], key
,
3647 path
->slots
[level
] + 1);
3653 const char* btrfs_group_type_str(u64 flag
)
3655 u64 mask
= BTRFS_BLOCK_GROUP_TYPE_MASK
|
3656 BTRFS_SPACE_INFO_GLOBAL_RSV
;
3658 switch (flag
& mask
) {
3659 case BTRFS_BLOCK_GROUP_DATA
:
3661 case BTRFS_BLOCK_GROUP_SYSTEM
:
3663 case BTRFS_BLOCK_GROUP_METADATA
:
3665 case BTRFS_BLOCK_GROUP_DATA
|BTRFS_BLOCK_GROUP_METADATA
:
3666 return "Data+Metadata";
3667 case BTRFS_SPACE_INFO_GLOBAL_RSV
:
3668 return "GlobalReserve";
3674 const char* btrfs_group_profile_str(u64 flag
)
3676 switch (flag
& BTRFS_BLOCK_GROUP_PROFILE_MASK
) {
3679 case BTRFS_BLOCK_GROUP_RAID0
:
3681 case BTRFS_BLOCK_GROUP_RAID1
:
3683 case BTRFS_BLOCK_GROUP_RAID5
:
3685 case BTRFS_BLOCK_GROUP_RAID6
:
3687 case BTRFS_BLOCK_GROUP_DUP
:
3689 case BTRFS_BLOCK_GROUP_RAID10
:
3696 u64
disk_size(const char *path
)
3700 if (statfs(path
, &sfs
) < 0)
3703 return sfs
.f_bsize
* sfs
.f_blocks
;
3706 u64
get_partition_size(const char *dev
)
3709 int fd
= open(dev
, O_RDONLY
);
3713 if (ioctl(fd
, BLKGETSIZE64
, &result
) < 0) {
3722 int btrfs_tree_search2_ioctl_supported(int fd
)
3724 struct btrfs_ioctl_search_args_v2
*args2
;
3725 struct btrfs_ioctl_search_key
*sk
;
3726 int args2_size
= 1024;
3727 char args2_buf
[args2_size
];
3729 static int v2_supported
= -1;
3731 if (v2_supported
!= -1)
3732 return v2_supported
;
3734 args2
= (struct btrfs_ioctl_search_args_v2
*)args2_buf
;
3738 * Search for the extent tree item in the root tree.
3740 sk
->tree_id
= BTRFS_ROOT_TREE_OBJECTID
;
3741 sk
->min_objectid
= BTRFS_EXTENT_TREE_OBJECTID
;
3742 sk
->max_objectid
= BTRFS_EXTENT_TREE_OBJECTID
;
3743 sk
->min_type
= BTRFS_ROOT_ITEM_KEY
;
3744 sk
->max_type
= BTRFS_ROOT_ITEM_KEY
;
3746 sk
->max_offset
= (u64
)-1;
3747 sk
->min_transid
= 0;
3748 sk
->max_transid
= (u64
)-1;
3750 args2
->buf_size
= args2_size
- sizeof(struct btrfs_ioctl_search_args_v2
);
3751 ret
= ioctl(fd
, BTRFS_IOC_TREE_SEARCH_V2
, args2
);
3752 if (ret
== -EOPNOTSUPP
)
3759 return v2_supported
;
3762 int btrfs_check_nodesize(u32 nodesize
, u32 sectorsize
, u64 features
)
3764 if (nodesize
< sectorsize
) {
3765 error("illegal nodesize %u (smaller than %u)",
3766 nodesize
, sectorsize
);
3768 } else if (nodesize
> BTRFS_MAX_METADATA_BLOCKSIZE
) {
3769 error("illegal nodesize %u (larger than %u)",
3770 nodesize
, BTRFS_MAX_METADATA_BLOCKSIZE
);
3772 } else if (nodesize
& (sectorsize
- 1)) {
3773 error("illegal nodesize %u (not aligned to %u)",
3774 nodesize
, sectorsize
);
3776 } else if (features
& BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS
&&
3777 nodesize
!= sectorsize
) {
3778 error("illegal nodesize %u (not equal to %u for mixed block group)",
3779 nodesize
, sectorsize
);
3786 * Copy a path argument from SRC to DEST and check the SRC length if it's at
3787 * most PATH_MAX and fits into DEST. DESTLEN is supposed to be exact size of
3789 * The destination buffer is zero terminated.
3790 * Return < 0 for error, 0 otherwise.
3792 int arg_copy_path(char *dest
, const char *src
, int destlen
)
3794 size_t len
= strlen(src
);
3796 if (len
>= PATH_MAX
|| len
>= destlen
)
3797 return -ENAMETOOLONG
;
3799 __strncpy_null(dest
, src
, destlen
);
3804 unsigned int get_unit_mode_from_arg(int *argc
, char *argv
[], int df_mode
)
3806 unsigned int unit_mode
= UNITS_DEFAULT
;
3810 for (arg_i
= 0; arg_i
< *argc
; arg_i
++) {
3811 if (!strcmp(argv
[arg_i
], "--"))
3814 if (!strcmp(argv
[arg_i
], "--raw")) {
3815 unit_mode
= UNITS_RAW
;
3819 if (!strcmp(argv
[arg_i
], "--human-readable")) {
3820 unit_mode
= UNITS_HUMAN_BINARY
;
3825 if (!strcmp(argv
[arg_i
], "--iec")) {
3826 units_set_mode(&unit_mode
, UNITS_BINARY
);
3830 if (!strcmp(argv
[arg_i
], "--si")) {
3831 units_set_mode(&unit_mode
, UNITS_DECIMAL
);
3836 if (!strcmp(argv
[arg_i
], "--kbytes")) {
3837 units_set_base(&unit_mode
, UNITS_KBYTES
);
3841 if (!strcmp(argv
[arg_i
], "--mbytes")) {
3842 units_set_base(&unit_mode
, UNITS_MBYTES
);
3846 if (!strcmp(argv
[arg_i
], "--gbytes")) {
3847 units_set_base(&unit_mode
, UNITS_GBYTES
);
3851 if (!strcmp(argv
[arg_i
], "--tbytes")) {
3852 units_set_base(&unit_mode
, UNITS_TBYTES
);
3860 if (!strcmp(argv
[arg_i
], "-b")) {
3861 unit_mode
= UNITS_RAW
;
3865 if (!strcmp(argv
[arg_i
], "-h")) {
3866 unit_mode
= UNITS_HUMAN_BINARY
;
3870 if (!strcmp(argv
[arg_i
], "-H")) {
3871 unit_mode
= UNITS_HUMAN_DECIMAL
;
3875 if (!strcmp(argv
[arg_i
], "-k")) {
3876 units_set_base(&unit_mode
, UNITS_KBYTES
);
3880 if (!strcmp(argv
[arg_i
], "-m")) {
3881 units_set_base(&unit_mode
, UNITS_MBYTES
);
3885 if (!strcmp(argv
[arg_i
], "-g")) {
3886 units_set_base(&unit_mode
, UNITS_GBYTES
);
3890 if (!strcmp(argv
[arg_i
], "-t")) {
3891 units_set_base(&unit_mode
, UNITS_TBYTES
);
3897 for (arg_i
= 0, arg_end
= 0; arg_i
< *argc
; arg_i
++) {
3900 argv
[arg_end
] = argv
[arg_i
];
3909 int string_is_numerical(const char *str
)
3911 if (!(*str
>= '0' && *str
<= '9'))
3913 while (*str
>= '0' && *str
<= '9')
3921 * Preprocess @argv with getopt_long to reorder options and consume the "--"
3923 * Unknown short and long options are reported, optionally the @usage is printed
3926 void clean_args_no_options(int argc
, char *argv
[], const char * const *usagestr
)
3928 static const struct option long_options
[] = {
3933 int c
= getopt_long(argc
, argv
, "", long_options
, NULL
);
3947 * Same as clean_args_no_options but pass through arguments that could look
3948 * like short options. Eg. reisze which takes a negative resize argument like
3951 * This accepts only two forms:
3952 * - "-- option1 option2 ..."
3953 * - "option1 option2 ..."
3955 void clean_args_no_options_relaxed(int argc
, char *argv
[], const char * const *usagestr
)
3960 if (strcmp(argv
[1], "--") == 0)
3964 /* Subvolume helper functions */
3966 * test if name is a correct subvolume name
3967 * this function return
3968 * 0-> name is not a correct subvolume name
3969 * 1-> name is a correct subvolume name
3971 int test_issubvolname(const char *name
)
3973 return name
[0] != '\0' && !strchr(name
, '/') &&
3974 strcmp(name
, ".") && strcmp(name
, "..");
3978 * Test if path is a subvolume
3980 * 0 - path exists but it is not a subvolume
3981 * 1 - path exists and it is a subvolume
3984 int test_issubvolume(const char *path
)
3990 res
= stat(path
, &st
);
3994 if (st
.st_ino
!= BTRFS_FIRST_FREE_OBJECTID
|| !S_ISDIR(st
.st_mode
))
3997 res
= statfs(path
, &stfs
);
4001 return (int)stfs
.f_type
== BTRFS_SUPER_MAGIC
;
4004 const char *subvol_strip_mountpoint(const char *mnt
, const char *full_path
)
4006 int len
= strlen(mnt
);
4010 if (mnt
[len
- 1] != '/')
4013 return full_path
+ len
;
4020 * 1: Error; and error info printed to the terminal. Fixme.
4021 * 2: If the fullpath is root tree instead of subvol tree
4023 int get_subvol_info(const char *fullpath
, struct root_info
*get_ri
)
4030 const char *svpath
= NULL
;
4031 DIR *dirstream1
= NULL
;
4032 DIR *dirstream2
= NULL
;
4034 ret
= test_issubvolume(fullpath
);
4038 error("not a subvolume: %s", fullpath
);
4042 ret
= find_mount_root(fullpath
, &mnt
);
4046 error("%s doesn't belong to btrfs mount point", fullpath
);
4050 svpath
= subvol_strip_mountpoint(mnt
, fullpath
);
4052 fd
= btrfs_open_dir(fullpath
, &dirstream1
, 1);
4056 ret
= btrfs_list_get_path_rootid(fd
, &sv_id
);
4058 error("can't get rootid for '%s'", fullpath
);
4062 mntfd
= btrfs_open_dir(mnt
, &dirstream2
, 1);
4066 if (sv_id
== BTRFS_FS_TREE_OBJECTID
) {
4069 * So that caller may decide if thats an error or just fine.
4074 memset(get_ri
, 0, sizeof(*get_ri
));
4075 get_ri
->root_id
= sv_id
;
4077 ret
= btrfs_get_subvol(mntfd
, get_ri
);
4079 error("can't find '%s': %d", svpath
, ret
);
4082 close_file_or_dir(mntfd
, dirstream2
);
4083 close_file_or_dir(fd
, dirstream1
);
4089 void init_rand_seed(u64 seed
)
4093 /* only use the last 48 bits */
4094 for (i
= 0; i
< 3; i
++) {
4095 rand_seed
[i
] = (unsigned short)(seed
^ (unsigned short)(-1));
4098 rand_seed_initlized
= 1;
4101 static void __init_seed(void)
4107 if(rand_seed_initlized
)
4109 /* Use urandom as primary seed source. */
4110 fd
= open("/dev/urandom", O_RDONLY
);
4112 ret
= read(fd
, rand_seed
, sizeof(rand_seed
));
4114 if (ret
< sizeof(rand_seed
))
4118 /* Use time and pid as fallback seed */
4119 warning("failed to read /dev/urandom, use time and pid as random seed");
4120 gettimeofday(&tv
, 0);
4121 rand_seed
[0] = getpid() ^ (tv
.tv_sec
& 0xFFFF);
4122 rand_seed
[1] = getppid() ^ (tv
.tv_usec
& 0xFFFF);
4123 rand_seed
[2] = (tv
.tv_sec
^ tv
.tv_usec
) >> 16;
4125 rand_seed_initlized
= 1;
4132 * Don't use nrand48, its range is [0,2^31) The highest bit will alwasy
4133 * be 0. Use jrand48 to include the highest bit.
4135 return (u32
)jrand48(rand_seed
);
4138 unsigned int rand_range(unsigned int upper
)
4142 * Use the full 48bits to mod, which would be more uniformly
4145 return (unsigned int)(jrand48(rand_seed
) % upper
);