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btrfs-progs/utils.c
David Sterba 1c85c3de5a btrfs-progs: use existing rootid resolving helper in btrfs_list_get_path_rootid 
The utils helper is not verbose in case of an error, for now the helper
used for subvolume listing will print the error message but not
duplicate the ioctl anymore.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-11-09 13:47:28 +01:00

4252 lines
103 KiB
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/*
* Copyright (C) 2007 Oracle. All rights reserved.
* Copyright (C) 2008 Morey Roof. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <uuid/uuid.h>
#include <fcntl.h>
#include <unistd.h>
#include <mntent.h>
#include <ctype.h>
#include <linux/loop.h>
#include <linux/major.h>
#include <linux/kdev_t.h>
#include <limits.h>
#include <blkid/blkid.h>
#include <sys/vfs.h>
#include <sys/statfs.h>
#include <linux/magic.h>
#include <getopt.h>
#include <sys/utsname.h>
#include "kerncompat.h"
#include "radix-tree.h"
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "crc32c.h"
#include "utils.h"
#include "volumes.h"
#include "ioctl.h"
#include "commands.h"
#ifndef BLKDISCARD
#define BLKDISCARD _IO(0x12,119)
#endif
static int btrfs_scan_done = 0;
static char argv0_buf[ARGV0_BUF_SIZE] = "btrfs";
static int rand_seed_initlized = 0;
static unsigned short rand_seed[3];
const char *get_argv0_buf(void)
{
return argv0_buf;
}
void fixup_argv0(char **argv, const char *token)
{
int len = strlen(argv0_buf);
snprintf(argv0_buf + len, sizeof(argv0_buf) - len, " %s", token);
argv[0] = argv0_buf;
}
void set_argv0(char **argv)
{
strncpy(argv0_buf, argv[0], sizeof(argv0_buf));
argv0_buf[sizeof(argv0_buf) - 1] = 0;
}
int check_argc_exact(int nargs, int expected)
{
if (nargs < expected)
fprintf(stderr, "%s: too few arguments\n", argv0_buf);
if (nargs > expected)
fprintf(stderr, "%s: too many arguments\n", argv0_buf);
return nargs != expected;
}
int check_argc_min(int nargs, int expected)
{
if (nargs < expected) {
fprintf(stderr, "%s: too few arguments\n", argv0_buf);
return 1;
}
return 0;
}
int check_argc_max(int nargs, int expected)
{
if (nargs > expected) {
fprintf(stderr, "%s: too many arguments\n", argv0_buf);
return 1;
}
return 0;
}
/*
* Discard the given range in one go
*/
static int discard_range(int fd, u64 start, u64 len)
{
u64 range[2] = { start, len };
if (ioctl(fd, BLKDISCARD, &range) < 0)
return errno;
return 0;
}
/*
* Discard blocks in the given range in 1G chunks, the process is interruptible
*/
static int discard_blocks(int fd, u64 start, u64 len)
{
while (len > 0) {
/* 1G granularity */
u64 chunk_size = min_t(u64, len, 1*1024*1024*1024);
int ret;
ret = discard_range(fd, start, chunk_size);
if (ret)
return ret;
len -= chunk_size;
start += chunk_size;
}
return 0;
}
static u64 reference_root_table[] = {
[1] = BTRFS_ROOT_TREE_OBJECTID,
[2] = BTRFS_EXTENT_TREE_OBJECTID,
[3] = BTRFS_CHUNK_TREE_OBJECTID,
[4] = BTRFS_DEV_TREE_OBJECTID,
[5] = BTRFS_FS_TREE_OBJECTID,
[6] = BTRFS_CSUM_TREE_OBJECTID,
};
int test_uuid_unique(char *fs_uuid)
{
int unique = 1;
blkid_dev_iterate iter = NULL;
blkid_dev dev = NULL;
blkid_cache cache = NULL;
if (blkid_get_cache(&cache, NULL) < 0) {
printf("ERROR: lblkid cache get failed\n");
return 1;
}
blkid_probe_all(cache);
iter = blkid_dev_iterate_begin(cache);
blkid_dev_set_search(iter, "UUID", fs_uuid);
while (blkid_dev_next(iter, &dev) == 0) {
dev = blkid_verify(cache, dev);
if (dev) {
unique = 0;
break;
}
}
blkid_dev_iterate_end(iter);
blkid_put_cache(cache);
return unique;
}
/*
* Reserve space from free_tree.
* The algorithm is very simple, find the first cache_extent with enough space
* and allocate from its beginning.
*/
static int reserve_free_space(struct cache_tree *free_tree, u64 len,
u64 *ret_start)
{
struct cache_extent *cache;
int found = 0;
ASSERT(ret_start != NULL);
cache = first_cache_extent(free_tree);
while (cache) {
if (cache->size > len) {
found = 1;
*ret_start = cache->start;
cache->size -= len;
if (cache->size == 0) {
remove_cache_extent(free_tree, cache);
free(cache);
} else {
cache->start += len;
}
break;
}
cache = next_cache_extent(cache);
}
if (!found)
return -ENOSPC;
return 0;
}
static inline int write_temp_super(int fd, struct btrfs_super_block *sb,
u64 sb_bytenr)
{
u32 crc = ~(u32)0;
int ret;
crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE, crc,
BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
btrfs_csum_final(crc, &sb->csum[0]);
ret = pwrite(fd, sb, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
if (ret < BTRFS_SUPER_INFO_SIZE)
ret = (ret < 0 ? -errno : -EIO);
else
ret = 0;
return ret;
}
/*
* Setup temporary superblock at cfg->super_bynter
* Needed info are extracted from cfg, and root_bytenr, chunk_bytenr
*
* For now sys chunk array will be empty and dev_item is empty too.
* They will be re-initialized at temp chunk tree setup.
*
* The superblock signature is not valid, denotes a partially created
* filesystem, needs to be finalized.
*/
static int setup_temp_super(int fd, struct btrfs_mkfs_config *cfg,
u64 root_bytenr, u64 chunk_bytenr)
{
unsigned char chunk_uuid[BTRFS_UUID_SIZE];
char super_buf[BTRFS_SUPER_INFO_SIZE];
struct btrfs_super_block *super = (struct btrfs_super_block *)super_buf;
int ret;
memset(super_buf, 0, BTRFS_SUPER_INFO_SIZE);
cfg->num_bytes = round_down(cfg->num_bytes, cfg->sectorsize);
if (*cfg->fs_uuid) {
if (uuid_parse(cfg->fs_uuid, super->fsid) != 0) {
error("cound not parse UUID: %s", cfg->fs_uuid);
ret = -EINVAL;
goto out;
}
if (!test_uuid_unique(cfg->fs_uuid)) {
error("non-unique UUID: %s", cfg->fs_uuid);
ret = -EINVAL;
goto out;
}
} else {
uuid_generate(super->fsid);
uuid_unparse(super->fsid, cfg->fs_uuid);
}
uuid_generate(chunk_uuid);
uuid_unparse(chunk_uuid, cfg->chunk_uuid);
btrfs_set_super_bytenr(super, cfg->super_bytenr);
btrfs_set_super_num_devices(super, 1);
btrfs_set_super_magic(super, BTRFS_MAGIC_PARTIAL);
btrfs_set_super_generation(super, 1);
btrfs_set_super_root(super, root_bytenr);
btrfs_set_super_chunk_root(super, chunk_bytenr);
btrfs_set_super_total_bytes(super, cfg->num_bytes);
/*
* Temporary filesystem will only have 6 tree roots:
* chunk tree, root tree, extent_tree, device tree, fs tree
* and csum tree.
*/
btrfs_set_super_bytes_used(super, 6 * cfg->nodesize);
btrfs_set_super_sectorsize(super, cfg->sectorsize);
btrfs_set_super_leafsize(super, cfg->nodesize);
btrfs_set_super_nodesize(super, cfg->nodesize);
btrfs_set_super_stripesize(super, cfg->stripesize);
btrfs_set_super_csum_type(super, BTRFS_CSUM_TYPE_CRC32);
btrfs_set_super_chunk_root(super, chunk_bytenr);
btrfs_set_super_cache_generation(super, -1);
btrfs_set_super_incompat_flags(super, cfg->features);
if (cfg->label)
__strncpy_null(super->label, cfg->label, BTRFS_LABEL_SIZE - 1);
/* Sys chunk array will be re-initialized at chunk tree init time */
super->sys_chunk_array_size = 0;
ret = write_temp_super(fd, super, cfg->super_bytenr);
out:
return ret;
}
/*
* Setup an extent buffer for tree block.
*/
static int setup_temp_extent_buffer(struct extent_buffer *buf,
struct btrfs_mkfs_config *cfg,
u64 bytenr, u64 owner)
{
unsigned char fsid[BTRFS_FSID_SIZE];
unsigned char chunk_uuid[BTRFS_UUID_SIZE];
int ret;
ret = uuid_parse(cfg->fs_uuid, fsid);
if (ret)
return -EINVAL;
ret = uuid_parse(cfg->chunk_uuid, chunk_uuid);
if (ret)
return -EINVAL;
memset(buf->data, 0, cfg->nodesize);
buf->len = cfg->nodesize;
btrfs_set_header_bytenr(buf, bytenr);
btrfs_set_header_generation(buf, 1);
btrfs_set_header_backref_rev(buf, BTRFS_MIXED_BACKREF_REV);
btrfs_set_header_owner(buf, owner);
btrfs_set_header_flags(buf, BTRFS_HEADER_FLAG_WRITTEN);
write_extent_buffer(buf, chunk_uuid, btrfs_header_chunk_tree_uuid(buf),
BTRFS_UUID_SIZE);
write_extent_buffer(buf, fsid, btrfs_header_fsid(), BTRFS_FSID_SIZE);
return 0;
}
static inline int write_temp_extent_buffer(int fd, struct extent_buffer *buf,
u64 bytenr)
{
int ret;
csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
/* Temporary extent buffer is always mapped 1:1 on disk */
ret = pwrite(fd, buf->data, buf->len, bytenr);
if (ret < buf->len)
ret = (ret < 0 ? ret : -EIO);
else
ret = 0;
return ret;
}
/*
* Insert a root item for temporary tree root
*
* Only used in make_btrfs_v2().
*/
static void insert_temp_root_item(struct extent_buffer *buf,
struct btrfs_mkfs_config *cfg,
int *slot, u32 *itemoff, u64 objectid,
u64 bytenr)
{
struct btrfs_root_item root_item;
struct btrfs_inode_item *inode_item;
struct btrfs_disk_key disk_key;
btrfs_set_header_nritems(buf, *slot + 1);
(*itemoff) -= sizeof(root_item);
memset(&root_item, 0, sizeof(root_item));
inode_item = &root_item.inode;
btrfs_set_stack_inode_generation(inode_item, 1);
btrfs_set_stack_inode_size(inode_item, 3);
btrfs_set_stack_inode_nlink(inode_item, 1);
btrfs_set_stack_inode_nbytes(inode_item, cfg->nodesize);
btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
btrfs_set_root_refs(&root_item, 1);
btrfs_set_root_used(&root_item, cfg->nodesize);
btrfs_set_root_generation(&root_item, 1);
btrfs_set_root_bytenr(&root_item, bytenr);
memset(&disk_key, 0, sizeof(disk_key));
btrfs_set_disk_key_type(&disk_key, BTRFS_ROOT_ITEM_KEY);
btrfs_set_disk_key_objectid(&disk_key, objectid);
btrfs_set_disk_key_offset(&disk_key, 0);
btrfs_set_item_key(buf, &disk_key, *slot);
btrfs_set_item_offset(buf, btrfs_item_nr(*slot), *itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(*slot), sizeof(root_item));
write_extent_buffer(buf, &root_item,
btrfs_item_ptr_offset(buf, *slot),
sizeof(root_item));
(*slot)++;
}
static int setup_temp_root_tree(int fd, struct btrfs_mkfs_config *cfg,
u64 root_bytenr, u64 extent_bytenr,
u64 dev_bytenr, u64 fs_bytenr, u64 csum_bytenr)
{
struct extent_buffer *buf = NULL;
u32 itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize);
int slot = 0;
int ret;
/*
* Provided bytenr must in ascending order, or tree root will have a
* bad key order.
*/
if (!(root_bytenr < extent_bytenr && extent_bytenr < dev_bytenr &&
dev_bytenr < fs_bytenr && fs_bytenr < csum_bytenr)) {
error("bad tree bytenr order: "
"root < extent %llu < %llu, "
"extent < dev %llu < %llu, "
"dev < fs %llu < %llu, "
"fs < csum %llu < %llu",
(unsigned long long)root_bytenr,
(unsigned long long)extent_bytenr,
(unsigned long long)extent_bytenr,
(unsigned long long)dev_bytenr,
(unsigned long long)dev_bytenr,
(unsigned long long)fs_bytenr,
(unsigned long long)fs_bytenr,
(unsigned long long)csum_bytenr);
return -EINVAL;
}
buf = malloc(sizeof(*buf) + cfg->nodesize);
if (!buf)
return -ENOMEM;
ret = setup_temp_extent_buffer(buf, cfg, root_bytenr,
BTRFS_ROOT_TREE_OBJECTID);
if (ret < 0)
goto out;
insert_temp_root_item(buf, cfg, &slot, &itemoff,
BTRFS_EXTENT_TREE_OBJECTID, extent_bytenr);
insert_temp_root_item(buf, cfg, &slot, &itemoff,
BTRFS_DEV_TREE_OBJECTID, dev_bytenr);
insert_temp_root_item(buf, cfg, &slot, &itemoff,
BTRFS_FS_TREE_OBJECTID, fs_bytenr);
insert_temp_root_item(buf, cfg, &slot, &itemoff,
BTRFS_CSUM_TREE_OBJECTID, csum_bytenr);
ret = write_temp_extent_buffer(fd, buf, root_bytenr);
out:
free(buf);
return ret;
}
static int insert_temp_dev_item(int fd, struct extent_buffer *buf,
struct btrfs_mkfs_config *cfg,
int *slot, u32 *itemoff)
{
struct btrfs_disk_key disk_key;
struct btrfs_dev_item *dev_item;
char super_buf[BTRFS_SUPER_INFO_SIZE];
unsigned char dev_uuid[BTRFS_UUID_SIZE];
unsigned char fsid[BTRFS_FSID_SIZE];
struct btrfs_super_block *super = (struct btrfs_super_block *)super_buf;
int ret;
ret = pread(fd, super_buf, BTRFS_SUPER_INFO_SIZE, cfg->super_bytenr);
if (ret < BTRFS_SUPER_INFO_SIZE) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
}
btrfs_set_header_nritems(buf, *slot + 1);
(*itemoff) -= sizeof(*dev_item);
/* setup device item 1, 0 is for replace case */
btrfs_set_disk_key_type(&disk_key, BTRFS_DEV_ITEM_KEY);
btrfs_set_disk_key_objectid(&disk_key, BTRFS_DEV_ITEMS_OBJECTID);
btrfs_set_disk_key_offset(&disk_key, 1);
btrfs_set_item_key(buf, &disk_key, *slot);
btrfs_set_item_offset(buf, btrfs_item_nr(*slot), *itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(*slot), sizeof(*dev_item));
dev_item = btrfs_item_ptr(buf, *slot, struct btrfs_dev_item);
/* Generate device uuid */
uuid_generate(dev_uuid);
write_extent_buffer(buf, dev_uuid,
(unsigned long)btrfs_device_uuid(dev_item),
BTRFS_UUID_SIZE);
uuid_parse(cfg->fs_uuid, fsid);
write_extent_buffer(buf, fsid,
(unsigned long)btrfs_device_fsid(dev_item),
BTRFS_FSID_SIZE);
btrfs_set_device_id(buf, dev_item, 1);
btrfs_set_device_generation(buf, dev_item, 0);
btrfs_set_device_total_bytes(buf, dev_item, cfg->num_bytes);
/*
* The number must match the initial SYSTEM and META chunk size
*/
btrfs_set_device_bytes_used(buf, dev_item,
BTRFS_MKFS_SYSTEM_GROUP_SIZE +
BTRFS_CONVERT_META_GROUP_SIZE);
btrfs_set_device_io_align(buf, dev_item, cfg->sectorsize);
btrfs_set_device_io_width(buf, dev_item, cfg->sectorsize);
btrfs_set_device_sector_size(buf, dev_item, cfg->sectorsize);
btrfs_set_device_type(buf, dev_item, 0);
/* Super dev_item is not complete, copy the complete one to sb */
read_extent_buffer(buf, &super->dev_item, (unsigned long)dev_item,
sizeof(*dev_item));
ret = write_temp_super(fd, super, cfg->super_bytenr);
(*slot)++;
out:
return ret;
}
static int insert_temp_chunk_item(int fd, struct extent_buffer *buf,
struct btrfs_mkfs_config *cfg,
int *slot, u32 *itemoff, u64 start, u64 len,
u64 type)
{
struct btrfs_chunk *chunk;
struct btrfs_disk_key disk_key;
char super_buf[BTRFS_SUPER_INFO_SIZE];
struct btrfs_super_block *sb = (struct btrfs_super_block *)super_buf;
int ret = 0;
ret = pread(fd, super_buf, BTRFS_SUPER_INFO_SIZE,
cfg->super_bytenr);
if (ret < BTRFS_SUPER_INFO_SIZE) {
ret = (ret < 0 ? ret : -EIO);
return ret;
}
btrfs_set_header_nritems(buf, *slot + 1);
(*itemoff) -= btrfs_chunk_item_size(1);
btrfs_set_disk_key_type(&disk_key, BTRFS_CHUNK_ITEM_KEY);
btrfs_set_disk_key_objectid(&disk_key, BTRFS_FIRST_CHUNK_TREE_OBJECTID);
btrfs_set_disk_key_offset(&disk_key, start);
btrfs_set_item_key(buf, &disk_key, *slot);
btrfs_set_item_offset(buf, btrfs_item_nr(*slot), *itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(*slot),
btrfs_chunk_item_size(1));
chunk = btrfs_item_ptr(buf, *slot, struct btrfs_chunk);
btrfs_set_chunk_length(buf, chunk, len);
btrfs_set_chunk_owner(buf, chunk, BTRFS_EXTENT_TREE_OBJECTID);
btrfs_set_chunk_stripe_len(buf, chunk, 64 * 1024);
btrfs_set_chunk_type(buf, chunk, type);
btrfs_set_chunk_io_align(buf, chunk, cfg->sectorsize);
btrfs_set_chunk_io_width(buf, chunk, cfg->sectorsize);
btrfs_set_chunk_sector_size(buf, chunk, cfg->sectorsize);
btrfs_set_chunk_num_stripes(buf, chunk, 1);
/* TODO: Support DUP profile for system chunk */
btrfs_set_stripe_devid_nr(buf, chunk, 0, 1);
/* We are doing 1:1 mapping, so start is its dev offset */
btrfs_set_stripe_offset_nr(buf, chunk, 0, start);
write_extent_buffer(buf, &sb->dev_item.uuid,
(unsigned long)btrfs_stripe_dev_uuid_nr(chunk, 0),
BTRFS_UUID_SIZE);
(*slot)++;
/*
* If it's system chunk, also copy it to super block.
*/
if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
char *cur;
cur = (char *)sb->sys_chunk_array + sb->sys_chunk_array_size;
memcpy(cur, &disk_key, sizeof(disk_key));
cur += sizeof(disk_key);
read_extent_buffer(buf, cur, (unsigned long int)chunk,
btrfs_chunk_item_size(1));
sb->sys_chunk_array_size += btrfs_chunk_item_size(1) +
sizeof(disk_key);
ret = write_temp_super(fd, sb, cfg->super_bytenr);
}
return ret;
}
static int setup_temp_chunk_tree(int fd, struct btrfs_mkfs_config *cfg,
u64 sys_chunk_start, u64 meta_chunk_start,
u64 chunk_bytenr)
{
struct extent_buffer *buf = NULL;
u32 itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize);
int slot = 0;
int ret;
/* Must ensure SYS chunk starts before META chunk */
if (meta_chunk_start < sys_chunk_start) {
error("wrong chunk order: meta < system %llu < %llu",
(unsigned long long)meta_chunk_start,
(unsigned long long)sys_chunk_start);
return -EINVAL;
}
buf = malloc(sizeof(*buf) + cfg->nodesize);
if (!buf)
return -ENOMEM;
ret = setup_temp_extent_buffer(buf, cfg, chunk_bytenr,
BTRFS_CHUNK_TREE_OBJECTID);
if (ret < 0)
goto out;
ret = insert_temp_dev_item(fd, buf, cfg, &slot, &itemoff);
if (ret < 0)
goto out;
ret = insert_temp_chunk_item(fd, buf, cfg, &slot, &itemoff,
sys_chunk_start,
BTRFS_MKFS_SYSTEM_GROUP_SIZE,
BTRFS_BLOCK_GROUP_SYSTEM);
if (ret < 0)
goto out;
ret = insert_temp_chunk_item(fd, buf, cfg, &slot, &itemoff,
meta_chunk_start,
BTRFS_CONVERT_META_GROUP_SIZE,
BTRFS_BLOCK_GROUP_METADATA);
if (ret < 0)
goto out;
ret = write_temp_extent_buffer(fd, buf, chunk_bytenr);
out:
free(buf);
return ret;
}
static void insert_temp_dev_extent(struct extent_buffer *buf,
int *slot, u32 *itemoff, u64 start, u64 len)
{
struct btrfs_dev_extent *dev_extent;
struct btrfs_disk_key disk_key;
btrfs_set_header_nritems(buf, *slot + 1);
(*itemoff) -= sizeof(*dev_extent);
btrfs_set_disk_key_type(&disk_key, BTRFS_DEV_EXTENT_KEY);
btrfs_set_disk_key_objectid(&disk_key, 1);
btrfs_set_disk_key_offset(&disk_key, start);
btrfs_set_item_key(buf, &disk_key, *slot);
btrfs_set_item_offset(buf, btrfs_item_nr(*slot), *itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(*slot), sizeof(*dev_extent));
dev_extent = btrfs_item_ptr(buf, *slot, struct btrfs_dev_extent);
btrfs_set_dev_extent_chunk_objectid(buf, dev_extent,
BTRFS_FIRST_CHUNK_TREE_OBJECTID);
btrfs_set_dev_extent_length(buf, dev_extent, len);
btrfs_set_dev_extent_chunk_offset(buf, dev_extent, start);
btrfs_set_dev_extent_chunk_tree(buf, dev_extent,
BTRFS_CHUNK_TREE_OBJECTID);
(*slot)++;
}
static int setup_temp_dev_tree(int fd, struct btrfs_mkfs_config *cfg,
u64 sys_chunk_start, u64 meta_chunk_start,
u64 dev_bytenr)
{
struct extent_buffer *buf = NULL;
u32 itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize);
int slot = 0;
int ret;
/* Must ensure SYS chunk starts before META chunk */
if (meta_chunk_start < sys_chunk_start) {
error("wrong chunk order: meta < system %llu < %llu",
(unsigned long long)meta_chunk_start,
(unsigned long long)sys_chunk_start);
return -EINVAL;
}
buf = malloc(sizeof(*buf) + cfg->nodesize);
if (!buf)
return -ENOMEM;
ret = setup_temp_extent_buffer(buf, cfg, dev_bytenr,
BTRFS_DEV_TREE_OBJECTID);
if (ret < 0)
goto out;
insert_temp_dev_extent(buf, &slot, &itemoff, sys_chunk_start,
BTRFS_MKFS_SYSTEM_GROUP_SIZE);
insert_temp_dev_extent(buf, &slot, &itemoff, meta_chunk_start,
BTRFS_CONVERT_META_GROUP_SIZE);
ret = write_temp_extent_buffer(fd, buf, dev_bytenr);
out:
free(buf);
return ret;
}
static int setup_temp_fs_tree(int fd, struct btrfs_mkfs_config *cfg,
u64 fs_bytenr)
{
struct extent_buffer *buf = NULL;
int ret;
buf = malloc(sizeof(*buf) + cfg->nodesize);
if (!buf)
return -ENOMEM;
ret = setup_temp_extent_buffer(buf, cfg, fs_bytenr,
BTRFS_FS_TREE_OBJECTID);
if (ret < 0)
goto out;
/*
* Temporary fs tree is completely empty.
*/
ret = write_temp_extent_buffer(fd, buf, fs_bytenr);
out:
free(buf);
return ret;
}
static int setup_temp_csum_tree(int fd, struct btrfs_mkfs_config *cfg,
u64 csum_bytenr)
{
struct extent_buffer *buf = NULL;
int ret;
buf = malloc(sizeof(*buf) + cfg->nodesize);
if (!buf)
return -ENOMEM;
ret = setup_temp_extent_buffer(buf, cfg, csum_bytenr,
BTRFS_CSUM_TREE_OBJECTID);
if (ret < 0)
goto out;
/*
* Temporary csum tree is completely empty.
*/
ret = write_temp_extent_buffer(fd, buf, csum_bytenr);
out:
free(buf);
return ret;
}
/*
* Insert one temporary extent item.
*
* NOTE: if skinny_metadata is not enabled, this function must be called
* after all other trees are initialized.
* Or fs without skinny-metadata will be screwed up.
*/
static int insert_temp_extent_item(int fd, struct extent_buffer *buf,
struct btrfs_mkfs_config *cfg,
int *slot, u32 *itemoff, u64 bytenr,
u64 ref_root)
{
struct extent_buffer *tmp;
struct btrfs_extent_item *ei;
struct btrfs_extent_inline_ref *iref;
struct btrfs_disk_key disk_key;
struct btrfs_disk_key tree_info_key;
struct btrfs_tree_block_info *info;
int itemsize;
int skinny_metadata = cfg->features &
BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA;
int ret;
if (skinny_metadata)
itemsize = sizeof(*ei) + sizeof(*iref);
else
itemsize = sizeof(*ei) + sizeof(*iref) +
sizeof(struct btrfs_tree_block_info);
btrfs_set_header_nritems(buf, *slot + 1);
*(itemoff) -= itemsize;
if (skinny_metadata) {
btrfs_set_disk_key_type(&disk_key, BTRFS_METADATA_ITEM_KEY);
btrfs_set_disk_key_offset(&disk_key, 0);
} else {
btrfs_set_disk_key_type(&disk_key, BTRFS_EXTENT_ITEM_KEY);
btrfs_set_disk_key_offset(&disk_key, cfg->nodesize);
}
btrfs_set_disk_key_objectid(&disk_key, bytenr);
btrfs_set_item_key(buf, &disk_key, *slot);
btrfs_set_item_offset(buf, btrfs_item_nr(*slot), *itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(*slot), itemsize);
ei = btrfs_item_ptr(buf, *slot, struct btrfs_extent_item);
btrfs_set_extent_refs(buf, ei, 1);
btrfs_set_extent_generation(buf, ei, 1);
btrfs_set_extent_flags(buf, ei, BTRFS_EXTENT_FLAG_TREE_BLOCK);
if (skinny_metadata) {
iref = (struct btrfs_extent_inline_ref *)(ei + 1);
} else {
info = (struct btrfs_tree_block_info *)(ei + 1);
iref = (struct btrfs_extent_inline_ref *)(info + 1);
}
btrfs_set_extent_inline_ref_type(buf, iref,
BTRFS_TREE_BLOCK_REF_KEY);
btrfs_set_extent_inline_ref_offset(buf, iref, ref_root);
(*slot)++;
if (skinny_metadata)
return 0;
/*
* Lastly, check the tree block key by read the tree block
* Since we do 1:1 mapping for convert case, we can directly
* read the bytenr from disk
*/
tmp = malloc(sizeof(*tmp) + cfg->nodesize);
if (!tmp)
return -ENOMEM;
ret = setup_temp_extent_buffer(tmp, cfg, bytenr, ref_root);
if (ret < 0)
goto out;
ret = pread(fd, tmp->data, cfg->nodesize, bytenr);
if (ret < cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
}
if (btrfs_header_nritems(tmp) == 0) {
btrfs_set_disk_key_type(&tree_info_key, 0);
btrfs_set_disk_key_objectid(&tree_info_key, 0);
btrfs_set_disk_key_offset(&tree_info_key, 0);
} else {
btrfs_item_key(tmp, &tree_info_key, 0);
}
btrfs_set_tree_block_key(buf, info, &tree_info_key);
out:
free(tmp);
return ret;
}
static void insert_temp_block_group(struct extent_buffer *buf,
struct btrfs_mkfs_config *cfg,
int *slot, u32 *itemoff,
u64 bytenr, u64 len, u64 used, u64 flag)
{
struct btrfs_block_group_item bgi;
struct btrfs_disk_key disk_key;
btrfs_set_header_nritems(buf, *slot + 1);
(*itemoff) -= sizeof(bgi);
btrfs_set_disk_key_type(&disk_key, BTRFS_BLOCK_GROUP_ITEM_KEY);
btrfs_set_disk_key_objectid(&disk_key, bytenr);
btrfs_set_disk_key_offset(&disk_key, len);
btrfs_set_item_key(buf, &disk_key, *slot);
btrfs_set_item_offset(buf, btrfs_item_nr(*slot), *itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(*slot), sizeof(bgi));
btrfs_set_block_group_flags(&bgi, flag);
btrfs_set_block_group_used(&bgi, used);
btrfs_set_block_group_chunk_objectid(&bgi,
BTRFS_FIRST_CHUNK_TREE_OBJECTID);
write_extent_buffer(buf, &bgi, btrfs_item_ptr_offset(buf, *slot),
sizeof(bgi));
(*slot)++;
}
static int setup_temp_extent_tree(int fd, struct btrfs_mkfs_config *cfg,
u64 chunk_bytenr, u64 root_bytenr,
u64 extent_bytenr, u64 dev_bytenr,
u64 fs_bytenr, u64 csum_bytenr)
{
struct extent_buffer *buf = NULL;
u32 itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize);
int slot = 0;
int ret;
/*
* We must ensure provided bytenr are in ascending order,
* or extent tree key order will be broken.
*/
if (!(chunk_bytenr < root_bytenr && root_bytenr < extent_bytenr &&
extent_bytenr < dev_bytenr && dev_bytenr < fs_bytenr &&
fs_bytenr < csum_bytenr)) {
error("bad tree bytenr order: "
"chunk < root %llu < %llu, "
"root < extent %llu < %llu, "
"extent < dev %llu < %llu, "
"dev < fs %llu < %llu, "
"fs < csum %llu < %llu",
(unsigned long long)chunk_bytenr,
(unsigned long long)root_bytenr,
(unsigned long long)root_bytenr,
(unsigned long long)extent_bytenr,
(unsigned long long)extent_bytenr,
(unsigned long long)dev_bytenr,
(unsigned long long)dev_bytenr,
(unsigned long long)fs_bytenr,
(unsigned long long)fs_bytenr,
(unsigned long long)csum_bytenr);
return -EINVAL;
}
buf = malloc(sizeof(*buf) + cfg->nodesize);
if (!buf)
return -ENOMEM;
ret = setup_temp_extent_buffer(buf, cfg, extent_bytenr,
BTRFS_EXTENT_TREE_OBJECTID);
if (ret < 0)
goto out;
ret = insert_temp_extent_item(fd, buf, cfg, &slot, &itemoff,
chunk_bytenr, BTRFS_CHUNK_TREE_OBJECTID);
if (ret < 0)
goto out;
insert_temp_block_group(buf, cfg, &slot, &itemoff, chunk_bytenr,
BTRFS_MKFS_SYSTEM_GROUP_SIZE, cfg->nodesize,
BTRFS_BLOCK_GROUP_SYSTEM);
ret = insert_temp_extent_item(fd, buf, cfg, &slot, &itemoff,
root_bytenr, BTRFS_ROOT_TREE_OBJECTID);
if (ret < 0)
goto out;
/* 5 tree block used, root, extent, dev, fs and csum*/
insert_temp_block_group(buf, cfg, &slot, &itemoff, root_bytenr,
BTRFS_CONVERT_META_GROUP_SIZE, cfg->nodesize * 5,
BTRFS_BLOCK_GROUP_METADATA);
ret = insert_temp_extent_item(fd, buf, cfg, &slot, &itemoff,
extent_bytenr, BTRFS_EXTENT_TREE_OBJECTID);
if (ret < 0)
goto out;
ret = insert_temp_extent_item(fd, buf, cfg, &slot, &itemoff,
dev_bytenr, BTRFS_DEV_TREE_OBJECTID);
if (ret < 0)
goto out;
ret = insert_temp_extent_item(fd, buf, cfg, &slot, &itemoff,
fs_bytenr, BTRFS_FS_TREE_OBJECTID);
if (ret < 0)
goto out;
ret = insert_temp_extent_item(fd, buf, cfg, &slot, &itemoff,
csum_bytenr, BTRFS_CSUM_TREE_OBJECTID);
if (ret < 0)
goto out;
ret = write_temp_extent_buffer(fd, buf, extent_bytenr);
out:
free(buf);
return ret;
}
/*
* Improved version of make_btrfs().
*
* This one will
* 1) Do chunk allocation to avoid used data
* And after this function, extent type matches chunk type
* 2) Better structured code
* No super long hand written codes to initialized all tree blocks
* Split into small blocks and reuse codes.
* TODO: Reuse tree operation facilities by introducing new flags
*/
static int make_convert_btrfs(int fd, struct btrfs_mkfs_config *cfg,
struct btrfs_convert_context *cctx)
{
struct cache_tree *free = &cctx->free;
struct cache_tree *used = &cctx->used;
u64 sys_chunk_start;
u64 meta_chunk_start;
/* chunk tree bytenr, in system chunk */
u64 chunk_bytenr;
/* metadata trees bytenr, in metadata chunk */
u64 root_bytenr;
u64 extent_bytenr;
u64 dev_bytenr;
u64 fs_bytenr;
u64 csum_bytenr;
int ret;
/* Shouldn't happen */
BUG_ON(cache_tree_empty(used));
/*
* reserve space for temporary superblock first
* Here we allocate a little larger space, to keep later
* free space will be STRIPE_LEN aligned
*/
ret = reserve_free_space(free, BTRFS_STRIPE_LEN,
&cfg->super_bytenr);
if (ret < 0)
goto out;
/*
* Then reserve system chunk space
* TODO: Change system group size depending on cctx->total_bytes.
* If using current 4M, it can only handle less than one TB for
* worst case and then run out of sys space.
*/
ret = reserve_free_space(free, BTRFS_MKFS_SYSTEM_GROUP_SIZE,
&sys_chunk_start);
if (ret < 0)
goto out;
ret = reserve_free_space(free, BTRFS_CONVERT_META_GROUP_SIZE,
&meta_chunk_start);
if (ret < 0)
goto out;
/*
* Allocated meta/sys chunks will be mapped 1:1 with device offset.
*
* Inside the allocated metadata chunk, the layout will be:
* | offset | contents |
* -------------------------------------
* | +0 | tree root |
* | +nodesize | extent root |
* | +nodesize * 2 | device root |
* | +nodesize * 3 | fs tree |
* | +nodesize * 4 | csum tree |
* -------------------------------------
* Inside the allocated system chunk, the layout will be:
* | offset | contents |
* -------------------------------------
* | +0 | chunk root |
* -------------------------------------
*/
chunk_bytenr = sys_chunk_start;
root_bytenr = meta_chunk_start;
extent_bytenr = meta_chunk_start + cfg->nodesize;
dev_bytenr = meta_chunk_start + cfg->nodesize * 2;
fs_bytenr = meta_chunk_start + cfg->nodesize * 3;
csum_bytenr = meta_chunk_start + cfg->nodesize * 4;
ret = setup_temp_super(fd, cfg, root_bytenr, chunk_bytenr);
if (ret < 0)
goto out;
ret = setup_temp_root_tree(fd, cfg, root_bytenr, extent_bytenr,
dev_bytenr, fs_bytenr, csum_bytenr);
if (ret < 0)
goto out;
ret = setup_temp_chunk_tree(fd, cfg, sys_chunk_start, meta_chunk_start,
chunk_bytenr);
if (ret < 0)
goto out;
ret = setup_temp_dev_tree(fd, cfg, sys_chunk_start, meta_chunk_start,
dev_bytenr);
if (ret < 0)
goto out;
ret = setup_temp_fs_tree(fd, cfg, fs_bytenr);
if (ret < 0)
goto out;
ret = setup_temp_csum_tree(fd, cfg, csum_bytenr);
if (ret < 0)
goto out;
/*
* Setup extent tree last, since it may need to read tree block key
* for non-skinny metadata case.
*/
ret = setup_temp_extent_tree(fd, cfg, chunk_bytenr, root_bytenr,
extent_bytenr, dev_bytenr, fs_bytenr,
csum_bytenr);
out:
return ret;
}
/*
* @fs_uuid - if NULL, generates a UUID, returns back the new filesystem UUID
*
* The superblock signature is not valid, denotes a partially created
* filesystem, needs to be finalized.
*/
int make_btrfs(int fd, struct btrfs_mkfs_config *cfg,
struct btrfs_convert_context *cctx)
{
struct btrfs_super_block super;
struct extent_buffer *buf;
struct btrfs_root_item root_item;
struct btrfs_disk_key disk_key;
struct btrfs_extent_item *extent_item;
struct btrfs_inode_item *inode_item;
struct btrfs_chunk *chunk;
struct btrfs_dev_item *dev_item;
struct btrfs_dev_extent *dev_extent;
u8 chunk_tree_uuid[BTRFS_UUID_SIZE];
u8 *ptr;
int i;
int ret;
u32 itemoff;
u32 nritems = 0;
u64 first_free;
u64 ref_root;
u32 array_size;
u32 item_size;
int skinny_metadata = !!(cfg->features &
BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA);
u64 num_bytes;
if (cctx)
return make_convert_btrfs(fd, cfg, cctx);
buf = malloc(sizeof(*buf) + max(cfg->sectorsize, cfg->nodesize));
if (!buf)
return -ENOMEM;
first_free = BTRFS_SUPER_INFO_OFFSET + cfg->sectorsize * 2 - 1;
first_free &= ~((u64)cfg->sectorsize - 1);
memset(&super, 0, sizeof(super));
num_bytes = (cfg->num_bytes / cfg->sectorsize) * cfg->sectorsize;
if (*cfg->fs_uuid) {
if (uuid_parse(cfg->fs_uuid, super.fsid) != 0) {
error("cannot not parse UUID: %s", cfg->fs_uuid);
ret = -EINVAL;
goto out;
}
if (!test_uuid_unique(cfg->fs_uuid)) {
error("non-unique UUID: %s", cfg->fs_uuid);
ret = -EBUSY;
goto out;
}
} else {
uuid_generate(super.fsid);
if (cfg->fs_uuid)
uuid_unparse(super.fsid, cfg->fs_uuid);
}
uuid_generate(super.dev_item.uuid);
uuid_generate(chunk_tree_uuid);
btrfs_set_super_bytenr(&super, cfg->blocks[0]);
btrfs_set_super_num_devices(&super, 1);
btrfs_set_super_magic(&super, BTRFS_MAGIC_PARTIAL);
btrfs_set_super_generation(&super, 1);
btrfs_set_super_root(&super, cfg->blocks[1]);
btrfs_set_super_chunk_root(&super, cfg->blocks[3]);
btrfs_set_super_total_bytes(&super, num_bytes);
btrfs_set_super_bytes_used(&super, 6 * cfg->nodesize);
btrfs_set_super_sectorsize(&super, cfg->sectorsize);
btrfs_set_super_leafsize(&super, cfg->nodesize);
btrfs_set_super_nodesize(&super, cfg->nodesize);
btrfs_set_super_stripesize(&super, cfg->stripesize);
btrfs_set_super_csum_type(&super, BTRFS_CSUM_TYPE_CRC32);
btrfs_set_super_chunk_root_generation(&super, 1);
btrfs_set_super_cache_generation(&super, -1);
btrfs_set_super_incompat_flags(&super, cfg->features);
if (cfg->label)
__strncpy_null(super.label, cfg->label, BTRFS_LABEL_SIZE - 1);
/* create the tree of root objects */
memset(buf->data, 0, cfg->nodesize);
buf->len = cfg->nodesize;
btrfs_set_header_bytenr(buf, cfg->blocks[1]);
btrfs_set_header_nritems(buf, 4);
btrfs_set_header_generation(buf, 1);
btrfs_set_header_backref_rev(buf, BTRFS_MIXED_BACKREF_REV);
btrfs_set_header_owner(buf, BTRFS_ROOT_TREE_OBJECTID);
write_extent_buffer(buf, super.fsid, btrfs_header_fsid(),
BTRFS_FSID_SIZE);
write_extent_buffer(buf, chunk_tree_uuid,
btrfs_header_chunk_tree_uuid(buf),
BTRFS_UUID_SIZE);
/* create the items for the root tree */
memset(&root_item, 0, sizeof(root_item));
inode_item = &root_item.inode;
btrfs_set_stack_inode_generation(inode_item, 1);
btrfs_set_stack_inode_size(inode_item, 3);
btrfs_set_stack_inode_nlink(inode_item, 1);
btrfs_set_stack_inode_nbytes(inode_item, cfg->nodesize);
btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
btrfs_set_root_refs(&root_item, 1);
btrfs_set_root_used(&root_item, cfg->nodesize);
btrfs_set_root_generation(&root_item, 1);
memset(&disk_key, 0, sizeof(disk_key));
btrfs_set_disk_key_type(&disk_key, BTRFS_ROOT_ITEM_KEY);
btrfs_set_disk_key_offset(&disk_key, 0);
nritems = 0;
itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize) - sizeof(root_item);
btrfs_set_root_bytenr(&root_item, cfg->blocks[2]);
btrfs_set_disk_key_objectid(&disk_key, BTRFS_EXTENT_TREE_OBJECTID);
btrfs_set_item_key(buf, &disk_key, nritems);
btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(nritems),
sizeof(root_item));
write_extent_buffer(buf, &root_item, btrfs_item_ptr_offset(buf,
nritems), sizeof(root_item));
nritems++;
itemoff = itemoff - sizeof(root_item);
btrfs_set_root_bytenr(&root_item, cfg->blocks[4]);
btrfs_set_disk_key_objectid(&disk_key, BTRFS_DEV_TREE_OBJECTID);
btrfs_set_item_key(buf, &disk_key, nritems);
btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(nritems),
sizeof(root_item));
write_extent_buffer(buf, &root_item,
btrfs_item_ptr_offset(buf, nritems),
sizeof(root_item));
nritems++;
itemoff = itemoff - sizeof(root_item);
btrfs_set_root_bytenr(&root_item, cfg->blocks[5]);
btrfs_set_disk_key_objectid(&disk_key, BTRFS_FS_TREE_OBJECTID);
btrfs_set_item_key(buf, &disk_key, nritems);
btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(nritems),
sizeof(root_item));
write_extent_buffer(buf, &root_item,
btrfs_item_ptr_offset(buf, nritems),
sizeof(root_item));
nritems++;
itemoff = itemoff - sizeof(root_item);
btrfs_set_root_bytenr(&root_item, cfg->blocks[6]);
btrfs_set_disk_key_objectid(&disk_key, BTRFS_CSUM_TREE_OBJECTID);
btrfs_set_item_key(buf, &disk_key, nritems);
btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(nritems),
sizeof(root_item));
write_extent_buffer(buf, &root_item,
btrfs_item_ptr_offset(buf, nritems),
sizeof(root_item));
nritems++;
csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[1]);
if (ret != cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
}
/* create the items for the extent tree */
memset(buf->data + sizeof(struct btrfs_header), 0,
cfg->nodesize - sizeof(struct btrfs_header));
nritems = 0;
itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize);
for (i = 1; i < 7; i++) {
item_size = sizeof(struct btrfs_extent_item);
if (!skinny_metadata)
item_size += sizeof(struct btrfs_tree_block_info);
if (cfg->blocks[i] < first_free) {
error("block[%d] below first free: %llu < %llu",
i, (unsigned long long)cfg->blocks[i],
(unsigned long long)first_free);
ret = -EINVAL;
goto out;
}
if (cfg->blocks[i] < cfg->blocks[i - 1]) {
error("blocks %d and %d in reverse order: %llu < %llu",
i, i - 1,
(unsigned long long)cfg->blocks[i],
(unsigned long long)cfg->blocks[i - 1]);
ret = -EINVAL;
goto out;
}
/* create extent item */
itemoff -= item_size;
btrfs_set_disk_key_objectid(&disk_key, cfg->blocks[i]);
if (skinny_metadata) {
btrfs_set_disk_key_type(&disk_key,
BTRFS_METADATA_ITEM_KEY);
btrfs_set_disk_key_offset(&disk_key, 0);
} else {
btrfs_set_disk_key_type(&disk_key,
BTRFS_EXTENT_ITEM_KEY);
btrfs_set_disk_key_offset(&disk_key, cfg->nodesize);
}
btrfs_set_item_key(buf, &disk_key, nritems);
btrfs_set_item_offset(buf, btrfs_item_nr(nritems),
itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(nritems),
item_size);
extent_item = btrfs_item_ptr(buf, nritems,
struct btrfs_extent_item);
btrfs_set_extent_refs(buf, extent_item, 1);
btrfs_set_extent_generation(buf, extent_item, 1);
btrfs_set_extent_flags(buf, extent_item,
BTRFS_EXTENT_FLAG_TREE_BLOCK);
nritems++;
/* create extent ref */
ref_root = reference_root_table[i];
btrfs_set_disk_key_objectid(&disk_key, cfg->blocks[i]);
btrfs_set_disk_key_offset(&disk_key, ref_root);
btrfs_set_disk_key_type(&disk_key, BTRFS_TREE_BLOCK_REF_KEY);
btrfs_set_item_key(buf, &disk_key, nritems);
btrfs_set_item_offset(buf, btrfs_item_nr(nritems),
itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(nritems), 0);
nritems++;
}
btrfs_set_header_bytenr(buf, cfg->blocks[2]);
btrfs_set_header_owner(buf, BTRFS_EXTENT_TREE_OBJECTID);
btrfs_set_header_nritems(buf, nritems);
csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[2]);
if (ret != cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
}
/* create the chunk tree */
memset(buf->data + sizeof(struct btrfs_header), 0,
cfg->nodesize - sizeof(struct btrfs_header));
nritems = 0;
item_size = sizeof(*dev_item);
itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize) - item_size;
/* first device 1 (there is no device 0) */
btrfs_set_disk_key_objectid(&disk_key, BTRFS_DEV_ITEMS_OBJECTID);
btrfs_set_disk_key_offset(&disk_key, 1);
btrfs_set_disk_key_type(&disk_key, BTRFS_DEV_ITEM_KEY);
btrfs_set_item_key(buf, &disk_key, nritems);
btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(nritems), item_size);
dev_item = btrfs_item_ptr(buf, nritems, struct btrfs_dev_item);
btrfs_set_device_id(buf, dev_item, 1);
btrfs_set_device_generation(buf, dev_item, 0);
btrfs_set_device_total_bytes(buf, dev_item, num_bytes);
btrfs_set_device_bytes_used(buf, dev_item,
BTRFS_MKFS_SYSTEM_GROUP_SIZE);
btrfs_set_device_io_align(buf, dev_item, cfg->sectorsize);
btrfs_set_device_io_width(buf, dev_item, cfg->sectorsize);
btrfs_set_device_sector_size(buf, dev_item, cfg->sectorsize);
btrfs_set_device_type(buf, dev_item, 0);
write_extent_buffer(buf, super.dev_item.uuid,
(unsigned long)btrfs_device_uuid(dev_item),
BTRFS_UUID_SIZE);
write_extent_buffer(buf, super.fsid,
(unsigned long)btrfs_device_fsid(dev_item),
BTRFS_UUID_SIZE);
read_extent_buffer(buf, &super.dev_item, (unsigned long)dev_item,
sizeof(*dev_item));
nritems++;
item_size = btrfs_chunk_item_size(1);
itemoff = itemoff - item_size;
/* then we have chunk 0 */
btrfs_set_disk_key_objectid(&disk_key, BTRFS_FIRST_CHUNK_TREE_OBJECTID);
btrfs_set_disk_key_offset(&disk_key, 0);
btrfs_set_disk_key_type(&disk_key, BTRFS_CHUNK_ITEM_KEY);
btrfs_set_item_key(buf, &disk_key, nritems);
btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(nritems), item_size);
chunk = btrfs_item_ptr(buf, nritems, struct btrfs_chunk);
btrfs_set_chunk_length(buf, chunk, BTRFS_MKFS_SYSTEM_GROUP_SIZE);
btrfs_set_chunk_owner(buf, chunk, BTRFS_EXTENT_TREE_OBJECTID);
btrfs_set_chunk_stripe_len(buf, chunk, 64 * 1024);
btrfs_set_chunk_type(buf, chunk, BTRFS_BLOCK_GROUP_SYSTEM);
btrfs_set_chunk_io_align(buf, chunk, cfg->sectorsize);
btrfs_set_chunk_io_width(buf, chunk, cfg->sectorsize);
btrfs_set_chunk_sector_size(buf, chunk, cfg->sectorsize);
btrfs_set_chunk_num_stripes(buf, chunk, 1);
btrfs_set_stripe_devid_nr(buf, chunk, 0, 1);
btrfs_set_stripe_offset_nr(buf, chunk, 0, 0);
nritems++;
write_extent_buffer(buf, super.dev_item.uuid,
(unsigned long)btrfs_stripe_dev_uuid(&chunk->stripe),
BTRFS_UUID_SIZE);
/* copy the key for the chunk to the system array */
ptr = super.sys_chunk_array;
array_size = sizeof(disk_key);
memcpy(ptr, &disk_key, sizeof(disk_key));
ptr += sizeof(disk_key);
/* copy the chunk to the system array */
read_extent_buffer(buf, ptr, (unsigned long)chunk, item_size);
array_size += item_size;
ptr += item_size;
btrfs_set_super_sys_array_size(&super, array_size);
btrfs_set_header_bytenr(buf, cfg->blocks[3]);
btrfs_set_header_owner(buf, BTRFS_CHUNK_TREE_OBJECTID);
btrfs_set_header_nritems(buf, nritems);
csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[3]);
if (ret != cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
}
/* create the device tree */
memset(buf->data + sizeof(struct btrfs_header), 0,
cfg->nodesize - sizeof(struct btrfs_header));
nritems = 0;
itemoff = __BTRFS_LEAF_DATA_SIZE(cfg->nodesize) -
sizeof(struct btrfs_dev_extent);
btrfs_set_disk_key_objectid(&disk_key, 1);
btrfs_set_disk_key_offset(&disk_key, 0);
btrfs_set_disk_key_type(&disk_key, BTRFS_DEV_EXTENT_KEY);
btrfs_set_item_key(buf, &disk_key, nritems);
btrfs_set_item_offset(buf, btrfs_item_nr(nritems), itemoff);
btrfs_set_item_size(buf, btrfs_item_nr(nritems),
sizeof(struct btrfs_dev_extent));
dev_extent = btrfs_item_ptr(buf, nritems, struct btrfs_dev_extent);
btrfs_set_dev_extent_chunk_tree(buf, dev_extent,
BTRFS_CHUNK_TREE_OBJECTID);
btrfs_set_dev_extent_chunk_objectid(buf, dev_extent,
BTRFS_FIRST_CHUNK_TREE_OBJECTID);
btrfs_set_dev_extent_chunk_offset(buf, dev_extent, 0);
write_extent_buffer(buf, chunk_tree_uuid,
(unsigned long)btrfs_dev_extent_chunk_tree_uuid(dev_extent),
BTRFS_UUID_SIZE);
btrfs_set_dev_extent_length(buf, dev_extent,
BTRFS_MKFS_SYSTEM_GROUP_SIZE);
nritems++;
btrfs_set_header_bytenr(buf, cfg->blocks[4]);
btrfs_set_header_owner(buf, BTRFS_DEV_TREE_OBJECTID);
btrfs_set_header_nritems(buf, nritems);
csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[4]);
if (ret != cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
}
/* create the FS root */
memset(buf->data + sizeof(struct btrfs_header), 0,
cfg->nodesize - sizeof(struct btrfs_header));
btrfs_set_header_bytenr(buf, cfg->blocks[5]);
btrfs_set_header_owner(buf, BTRFS_FS_TREE_OBJECTID);
btrfs_set_header_nritems(buf, 0);
csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[5]);
if (ret != cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
}
/* finally create the csum root */
memset(buf->data + sizeof(struct btrfs_header), 0,
cfg->nodesize - sizeof(struct btrfs_header));
btrfs_set_header_bytenr(buf, cfg->blocks[6]);
btrfs_set_header_owner(buf, BTRFS_CSUM_TREE_OBJECTID);
btrfs_set_header_nritems(buf, 0);
csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, cfg->nodesize, cfg->blocks[6]);
if (ret != cfg->nodesize) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
}
/* and write out the super block */
memset(buf->data, 0, BTRFS_SUPER_INFO_SIZE);
memcpy(buf->data, &super, sizeof(super));
buf->len = BTRFS_SUPER_INFO_SIZE;
csum_tree_block_size(buf, BTRFS_CRC32_SIZE, 0);
ret = pwrite(fd, buf->data, BTRFS_SUPER_INFO_SIZE, cfg->blocks[0]);
if (ret != BTRFS_SUPER_INFO_SIZE) {
ret = (ret < 0 ? -errno : -EIO);
goto out;
}
ret = 0;
out:
free(buf);
return ret;
}
static const struct btrfs_fs_feature {
const char *name;
u64 flag;
const char *desc;
} mkfs_features[] = {
{ "mixed-bg", BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS,
"mixed data and metadata block groups" },
{ "extref", BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF,
"increased hardlink limit per file to 65536" },
{ "raid56", BTRFS_FEATURE_INCOMPAT_RAID56,
"raid56 extended format" },
{ "skinny-metadata", BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA,
"reduced-size metadata extent refs" },
{ "no-holes", BTRFS_FEATURE_INCOMPAT_NO_HOLES,
"no explicit hole extents for files" },
/* Keep this one last */
{ "list-all", BTRFS_FEATURE_LIST_ALL, NULL }
};
static int parse_one_fs_feature(const char *name, u64 *flags)
{
int i;
int found = 0;
for (i = 0; i < ARRAY_SIZE(mkfs_features); i++) {
if (name[0] == '^' &&
!strcmp(mkfs_features[i].name, name + 1)) {
*flags &= ~ mkfs_features[i].flag;
found = 1;
} else if (!strcmp(mkfs_features[i].name, name)) {
*flags |= mkfs_features[i].flag;
found = 1;
}
}
return !found;
}
void btrfs_parse_features_to_string(char *buf, u64 flags)
{
int i;
buf[0] = 0;
for (i = 0; i < ARRAY_SIZE(mkfs_features); i++) {
if (flags & mkfs_features[i].flag) {
if (*buf)
strcat(buf, ", ");
strcat(buf, mkfs_features[i].name);
}
}
}
void btrfs_process_fs_features(u64 flags)
{
int i;
for (i = 0; i < ARRAY_SIZE(mkfs_features); i++) {
if (flags & mkfs_features[i].flag) {
printf("Turning ON incompat feature '%s': %s\n",
mkfs_features[i].name,
mkfs_features[i].desc);
}
}
}
void btrfs_list_all_fs_features(u64 mask_disallowed)
{
int i;
fprintf(stderr, "Filesystem features available:\n");
for (i = 0; i < ARRAY_SIZE(mkfs_features) - 1; i++) {
char *is_default = "";
if (mkfs_features[i].flag & mask_disallowed)
continue;
if (mkfs_features[i].flag & BTRFS_MKFS_DEFAULT_FEATURES)
is_default = ", default";
fprintf(stderr, "%-20s- %s (0x%llx%s)\n",
mkfs_features[i].name,
mkfs_features[i].desc,
mkfs_features[i].flag,
is_default);
}
}
/*
* Return NULL if all features were parsed fine, otherwise return the name of
* the first unparsed.
*/
char* btrfs_parse_fs_features(char *namelist, u64 *flags)
{
char *this_char;
char *save_ptr = NULL; /* Satisfy static checkers */
for (this_char = strtok_r(namelist, ",", &save_ptr);
this_char != NULL;
this_char = strtok_r(NULL, ",", &save_ptr)) {
if (parse_one_fs_feature(this_char, flags))
return this_char;
}
return NULL;
}
void print_kernel_version(FILE *stream, u32 version)
{
u32 v[3];
v[0] = version & 0xFF;
v[1] = (version >> 8) & 0xFF;
v[2] = version >> 16;
fprintf(stream, "%u.%u", v[2], v[1]);
if (v[0])
fprintf(stream, ".%u", v[0]);
}
u32 get_running_kernel_version(void)
{
struct utsname utsbuf;
char *tmp;
char *saveptr = NULL;
u32 version;
uname(&utsbuf);
if (strcmp(utsbuf.sysname, "Linux") != 0) {
error("unsupported system: %s", utsbuf.sysname);
exit(1);
}
/* 1.2.3-4-name */
tmp = strchr(utsbuf.release, '-');
if (tmp)
*tmp = 0;
tmp = strtok_r(utsbuf.release, ".", &saveptr);
if (!string_is_numerical(tmp))
return (u32)-1;
version = atoi(tmp) << 16;
tmp = strtok_r(NULL, ".", &saveptr);
if (!string_is_numerical(tmp))
return (u32)-1;
version |= atoi(tmp) << 8;
tmp = strtok_r(NULL, ".", &saveptr);
if (tmp) {
if (!string_is_numerical(tmp))
return (u32)-1;
version |= atoi(tmp);
}
return version;
}
u64 btrfs_device_size(int fd, struct stat *st)
{
u64 size;
if (S_ISREG(st->st_mode)) {
return st->st_size;
}
if (!S_ISBLK(st->st_mode)) {
return 0;
}
if (ioctl(fd, BLKGETSIZE64, &size) >= 0) {
return size;
}
return 0;
}
static int zero_blocks(int fd, off_t start, size_t len)
{
char *buf = malloc(len);
int ret = 0;
ssize_t written;
if (!buf)
return -ENOMEM;
memset(buf, 0, len);
written = pwrite(fd, buf, len, start);
if (written != len)
ret = -EIO;
free(buf);
return ret;
}
#define ZERO_DEV_BYTES (2 * 1024 * 1024)
/* don't write outside the device by clamping the region to the device size */
static int zero_dev_clamped(int fd, off_t start, ssize_t len, u64 dev_size)
{
off_t end = max(start, start + len);
#ifdef __sparc__
/* and don't overwrite the disk labels on sparc */
start = max(start, 1024);
end = max(end, 1024);
#endif
start = min_t(u64, start, dev_size);
end = min_t(u64, end, dev_size);
return zero_blocks(fd, start, end - start);
}
int btrfs_add_to_fsid(struct btrfs_trans_handle *trans,
struct btrfs_root *root, int fd, const char *path,
u64 device_total_bytes, u32 io_width, u32 io_align,
u32 sectorsize)
{
struct btrfs_super_block *disk_super;
struct btrfs_super_block *super = root->fs_info->super_copy;
struct btrfs_device *device;
struct btrfs_dev_item *dev_item;
char *buf = NULL;
u64 fs_total_bytes;
u64 num_devs;
int ret;
device_total_bytes = (device_total_bytes / sectorsize) * sectorsize;
device = calloc(1, sizeof(*device));
if (!device) {
ret = -ENOMEM;
goto out;
}
buf = calloc(1, sectorsize);
if (!buf) {
ret = -ENOMEM;
goto out;
}
disk_super = (struct btrfs_super_block *)buf;
dev_item = &disk_super->dev_item;
uuid_generate(device->uuid);
device->devid = 0;
device->type = 0;
device->io_width = io_width;
device->io_align = io_align;
device->sector_size = sectorsize;
device->fd = fd;
device->writeable = 1;
device->total_bytes = device_total_bytes;
device->bytes_used = 0;
device->total_ios = 0;
device->dev_root = root->fs_info->dev_root;
device->name = strdup(path);
if (!device->name) {
ret = -ENOMEM;
goto out;
}
INIT_LIST_HEAD(&device->dev_list);
ret = btrfs_add_device(trans, root, device);
if (ret)
goto out;
fs_total_bytes = btrfs_super_total_bytes(super) + device_total_bytes;
btrfs_set_super_total_bytes(super, fs_total_bytes);
num_devs = btrfs_super_num_devices(super) + 1;
btrfs_set_super_num_devices(super, num_devs);
memcpy(disk_super, super, sizeof(*disk_super));
btrfs_set_super_bytenr(disk_super, BTRFS_SUPER_INFO_OFFSET);
btrfs_set_stack_device_id(dev_item, device->devid);
btrfs_set_stack_device_type(dev_item, device->type);
btrfs_set_stack_device_io_align(dev_item, device->io_align);
btrfs_set_stack_device_io_width(dev_item, device->io_width);
btrfs_set_stack_device_sector_size(dev_item, device->sector_size);
btrfs_set_stack_device_total_bytes(dev_item, device->total_bytes);
btrfs_set_stack_device_bytes_used(dev_item, device->bytes_used);
memcpy(&dev_item->uuid, device->uuid, BTRFS_UUID_SIZE);
ret = pwrite(fd, buf, sectorsize, BTRFS_SUPER_INFO_OFFSET);
BUG_ON(ret != sectorsize);
free(buf);
list_add(&device->dev_list, &root->fs_info->fs_devices->devices);
device->fs_devices = root->fs_info->fs_devices;
return 0;
out:
free(device);
free(buf);
return ret;
}
static int btrfs_wipe_existing_sb(int fd)
{
const char *off = NULL;
size_t len = 0;
loff_t offset;
char buf[BUFSIZ];
int ret = 0;
blkid_probe pr = NULL;
pr = blkid_new_probe();
if (!pr)
return -1;
if (blkid_probe_set_device(pr, fd, 0, 0)) {
ret = -1;
goto out;
}
ret = blkid_probe_lookup_value(pr, "SBMAGIC_OFFSET", &off, NULL);
if (!ret)
ret = blkid_probe_lookup_value(pr, "SBMAGIC", NULL, &len);
if (ret || len == 0 || off == NULL) {
/*
* If lookup fails, the probe did not find any values, eg. for
* a file image or a loop device. Soft error.
*/
ret = 1;
goto out;
}
offset = strtoll(off, NULL, 10);
if (len > sizeof(buf))
len = sizeof(buf);
memset(buf, 0, len);
ret = pwrite(fd, buf, len, offset);
if (ret < 0) {
error("cannot wipe existing superblock: %s", strerror(errno));
ret = -1;
} else if (ret != len) {
error("cannot wipe existing superblock: wrote %d of %zd", ret, len);
ret = -1;
}
fsync(fd);
out:
blkid_free_probe(pr);
return ret;
}
int btrfs_prepare_device(int fd, const char *file, u64 *block_count_ret,
u64 max_block_count, unsigned opflags)
{
u64 block_count;
struct stat st;
int i, ret;
ret = fstat(fd, &st);
if (ret < 0) {
error("unable to stat %s: %s", file, strerror(errno));
return 1;
}
block_count = btrfs_device_size(fd, &st);
if (block_count == 0) {
error("unable to determine size of %s", file);
return 1;
}
if (max_block_count)
block_count = min(block_count, max_block_count);
if (opflags & PREP_DEVICE_DISCARD) {
/*
* We intentionally ignore errors from the discard ioctl. It
* is not necessary for the mkfs functionality but just an
* optimization.
*/
if (discard_range(fd, 0, 0) == 0) {
if (opflags & PREP_DEVICE_VERBOSE)
printf("Performing full device TRIM (%s) ...\n",
pretty_size(block_count));
discard_blocks(fd, 0, block_count);
}
}
ret = zero_dev_clamped(fd, 0, ZERO_DEV_BYTES, block_count);
for (i = 0 ; !ret && i < BTRFS_SUPER_MIRROR_MAX; i++)
ret = zero_dev_clamped(fd, btrfs_sb_offset(i),
BTRFS_SUPER_INFO_SIZE, block_count);
if (!ret && (opflags & PREP_DEVICE_ZERO_END))
ret = zero_dev_clamped(fd, block_count - ZERO_DEV_BYTES,
ZERO_DEV_BYTES, block_count);
if (ret < 0) {
error("failed to zero device '%s': %s", file, strerror(-ret));
return 1;
}
ret = btrfs_wipe_existing_sb(fd);
if (ret < 0) {
error("cannot wipe superblocks on %s", file);
return 1;
}
*block_count_ret = block_count;
return 0;
}
int btrfs_make_root_dir(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid)
{
int ret;
struct btrfs_inode_item inode_item;
time_t now = time(NULL);
memset(&inode_item, 0, sizeof(inode_item));
btrfs_set_stack_inode_generation(&inode_item, trans->transid);
btrfs_set_stack_inode_size(&inode_item, 0);
btrfs_set_stack_inode_nlink(&inode_item, 1);
btrfs_set_stack_inode_nbytes(&inode_item, root->nodesize);
btrfs_set_stack_inode_mode(&inode_item, S_IFDIR | 0755);
btrfs_set_stack_timespec_sec(&inode_item.atime, now);
btrfs_set_stack_timespec_nsec(&inode_item.atime, 0);
btrfs_set_stack_timespec_sec(&inode_item.ctime, now);
btrfs_set_stack_timespec_nsec(&inode_item.ctime, 0);
btrfs_set_stack_timespec_sec(&inode_item.mtime, now);
btrfs_set_stack_timespec_nsec(&inode_item.mtime, 0);
btrfs_set_stack_timespec_sec(&inode_item.otime, 0);
btrfs_set_stack_timespec_nsec(&inode_item.otime, 0);
if (root->fs_info->tree_root == root)
btrfs_set_super_root_dir(root->fs_info->super_copy, objectid);
ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
if (ret)
goto error;
ret = btrfs_insert_inode_ref(trans, root, "..", 2, objectid, objectid, 0);
if (ret)
goto error;
btrfs_set_root_dirid(&root->root_item, objectid);
ret = 0;
error:
return ret;
}
/*
* checks if a path is a block device node
* Returns negative errno on failure, otherwise
* returns 1 for blockdev, 0 for not-blockdev
*/
int is_block_device(const char *path)
{
struct stat statbuf;
if (stat(path, &statbuf) < 0)
return -errno;
return !!S_ISBLK(statbuf.st_mode);
}
/*
* check if given path is a mount point
* return 1 if yes. 0 if no. -1 for error
*/
int is_mount_point(const char *path)
{
FILE *f;
struct mntent *mnt;
int ret = 0;
f = setmntent("/proc/self/mounts", "r");
if (f == NULL)
return -1;
while ((mnt = getmntent(f)) != NULL) {
if (strcmp(mnt->mnt_dir, path))
continue;
ret = 1;
break;
}
endmntent(f);
return ret;
}
static int is_reg_file(const char *path)
{
struct stat statbuf;
if (stat(path, &statbuf) < 0)
return -errno;
return S_ISREG(statbuf.st_mode);
}
/*
* This function checks if the given input parameter is
* an uuid or a path
* return <0 : some error in the given input
* return BTRFS_ARG_UNKNOWN: unknown input
* return BTRFS_ARG_UUID: given input is uuid
* return BTRFS_ARG_MNTPOINT: given input is path
* return BTRFS_ARG_REG: given input is regular file
* return BTRFS_ARG_BLKDEV: given input is block device
*/
int check_arg_type(const char *input)
{
uuid_t uuid;
char path[PATH_MAX];
if (!input)
return -EINVAL;
if (realpath(input, path)) {
if (is_block_device(path) == 1)
return BTRFS_ARG_BLKDEV;
if (is_mount_point(path) == 1)
return BTRFS_ARG_MNTPOINT;
if (is_reg_file(path))
return BTRFS_ARG_REG;
return BTRFS_ARG_UNKNOWN;
}
if (strlen(input) == (BTRFS_UUID_UNPARSED_SIZE - 1) &&
!uuid_parse(input, uuid))
return BTRFS_ARG_UUID;
return BTRFS_ARG_UNKNOWN;
}
/*
* Find the mount point for a mounted device.
* On success, returns 0 with mountpoint in *mp.
* On failure, returns -errno (not mounted yields -EINVAL)
* Is noisy on failures, expects to be given a mounted device.
*/
int get_btrfs_mount(const char *dev, char *mp, size_t mp_size)
{
int ret;
int fd = -1;
ret = is_block_device(dev);
if (ret <= 0) {
if (!ret) {
error("not a block device: %s", dev);
ret = -EINVAL;
} else {
error("cannot check %s: %s", dev, strerror(-ret));
}
goto out;
}
fd = open(dev, O_RDONLY);
if (fd < 0) {
ret = -errno;
error("cannot open %s: %s", dev, strerror(errno));
goto out;
}
ret = check_mounted_where(fd, dev, mp, mp_size, NULL);
if (!ret) {
ret = -EINVAL;
} else { /* mounted, all good */
ret = 0;
}
out:
if (fd != -1)
close(fd);
return ret;
}
/*
* Given a pathname, return a filehandle to:
* the original pathname or,
* if the pathname is a mounted btrfs device, to its mountpoint.
*
* On error, return -1, errno should be set.
*/
int open_path_or_dev_mnt(const char *path, DIR **dirstream, int verbose)
{
char mp[PATH_MAX];
int ret;
if (is_block_device(path)) {
ret = get_btrfs_mount(path, mp, sizeof(mp));
if (ret < 0) {
/* not a mounted btrfs dev */
error_on(verbose, "'%s' is not a mounted btrfs device",
path);
errno = EINVAL;
return -1;
}
ret = open_file_or_dir(mp, dirstream);
error_on(verbose && ret < 0, "can't access '%s': %s",
path, strerror(errno));
} else {
ret = btrfs_open_dir(path, dirstream, 1);
}
return ret;
}
/*
* Do the following checks before calling open_file_or_dir():
* 1: path is in a btrfs filesystem
* 2: path is a directory
*/
int btrfs_open_dir(const char *path, DIR **dirstream, int verbose)
{
struct statfs stfs;
struct stat st;
int ret;
if (statfs(path, &stfs) != 0) {
error_on(verbose, "cannot access '%s': %s", path,
strerror(errno));
return -1;
}
if (stfs.f_type != BTRFS_SUPER_MAGIC) {
error_on(verbose, "not a btrfs filesystem: %s", path);
return -2;
}
if (stat(path, &st) != 0) {
error_on(verbose, "cannot access '%s': %s", path,
strerror(errno));
return -1;
}
if (!S_ISDIR(st.st_mode)) {
error_on(verbose, "not a directory: %s", path);
return -3;
}
ret = open_file_or_dir(path, dirstream);
if (ret < 0) {
error_on(verbose, "cannot access '%s': %s", path,
strerror(errno));
}
return ret;
}
/* checks if a device is a loop device */
static int is_loop_device (const char* device) {
struct stat statbuf;
if(stat(device, &statbuf) < 0)
return -errno;
return (S_ISBLK(statbuf.st_mode) &&
MAJOR(statbuf.st_rdev) == LOOP_MAJOR);
}
/*
* Takes a loop device path (e.g. /dev/loop0) and returns
* the associated file (e.g. /images/my_btrfs.img) using
* loopdev API
*/
static int resolve_loop_device_with_loopdev(const char* loop_dev, char* loop_file)
{
int fd;
int ret;
struct loop_info64 lo64;
fd = open(loop_dev, O_RDONLY | O_NONBLOCK);
if (fd < 0)
return -errno;
ret = ioctl(fd, LOOP_GET_STATUS64, &lo64);
if (ret < 0) {
ret = -errno;
goto out;
}
memcpy(loop_file, lo64.lo_file_name, sizeof(lo64.lo_file_name));
loop_file[sizeof(lo64.lo_file_name)] = 0;
out:
close(fd);
return ret;
}
/* Takes a loop device path (e.g. /dev/loop0) and returns
* the associated file (e.g. /images/my_btrfs.img) */
static int resolve_loop_device(const char* loop_dev, char* loop_file,
int max_len)
{
int ret;
FILE *f;
char fmt[20];
char p[PATH_MAX];
char real_loop_dev[PATH_MAX];
if (!realpath(loop_dev, real_loop_dev))
return -errno;
snprintf(p, PATH_MAX, "/sys/block/%s/loop/backing_file", strrchr(real_loop_dev, '/'));
if (!(f = fopen(p, "r"))) {
if (errno == ENOENT)
/*
* It's possibly a partitioned loop device, which is
* resolvable with loopdev API.
*/
return resolve_loop_device_with_loopdev(loop_dev, loop_file);
return -errno;
}
snprintf(fmt, 20, "%%%i[^\n]", max_len-1);
ret = fscanf(f, fmt, loop_file);
fclose(f);
if (ret == EOF)
return -errno;
return 0;
}
/*
* Checks whether a and b are identical or device
* files associated with the same block device
*/
static int is_same_blk_file(const char* a, const char* b)
{
struct stat st_buf_a, st_buf_b;
char real_a[PATH_MAX];
char real_b[PATH_MAX];
if (!realpath(a, real_a))
strncpy_null(real_a, a);
if (!realpath(b, real_b))
strncpy_null(real_b, b);
/* Identical path? */
if (strcmp(real_a, real_b) == 0)
return 1;
if (stat(a, &st_buf_a) < 0 || stat(b, &st_buf_b) < 0) {
if (errno == ENOENT)
return 0;
return -errno;
}
/* Same blockdevice? */
if (S_ISBLK(st_buf_a.st_mode) && S_ISBLK(st_buf_b.st_mode) &&
st_buf_a.st_rdev == st_buf_b.st_rdev) {
return 1;
}
/* Hardlink? */
if (st_buf_a.st_dev == st_buf_b.st_dev &&
st_buf_a.st_ino == st_buf_b.st_ino) {
return 1;
}
return 0;
}
/* checks if a and b are identical or device
* files associated with the same block device or
* if one file is a loop device that uses the other
* file.
*/
static int is_same_loop_file(const char* a, const char* b)
{
char res_a[PATH_MAX];
char res_b[PATH_MAX];
const char* final_a = NULL;
const char* final_b = NULL;
int ret;
/* Resolve a if it is a loop device */
if((ret = is_loop_device(a)) < 0) {
if (ret == -ENOENT)
return 0;
return ret;
} else if (ret) {
ret = resolve_loop_device(a, res_a, sizeof(res_a));
if (ret < 0) {
if (errno != EPERM)
return ret;
} else {
final_a = res_a;
}
} else {
final_a = a;
}
/* Resolve b if it is a loop device */
if ((ret = is_loop_device(b)) < 0) {
if (ret == -ENOENT)
return 0;
return ret;
} else if (ret) {
ret = resolve_loop_device(b, res_b, sizeof(res_b));
if (ret < 0) {
if (errno != EPERM)
return ret;
} else {
final_b = res_b;
}
} else {
final_b = b;
}
return is_same_blk_file(final_a, final_b);
}
/* Checks if a file exists and is a block or regular file*/
static int is_existing_blk_or_reg_file(const char* filename)
{
struct stat st_buf;
if(stat(filename, &st_buf) < 0) {
if(errno == ENOENT)
return 0;
else
return -errno;
}
return (S_ISBLK(st_buf.st_mode) || S_ISREG(st_buf.st_mode));
}
/* Checks if a file is used (directly or indirectly via a loop device)
* by a device in fs_devices
*/
static int blk_file_in_dev_list(struct btrfs_fs_devices* fs_devices,
const char* file)
{
int ret;
struct list_head *head;
struct list_head *cur;
struct btrfs_device *device;
head = &fs_devices->devices;
list_for_each(cur, head) {
device = list_entry(cur, struct btrfs_device, dev_list);
if((ret = is_same_loop_file(device->name, file)))
return ret;
}
return 0;
}
/*
* Resolve a pathname to a device mapper node to /dev/mapper/<name>
* Returns NULL on invalid input or malloc failure; Other failures
* will be handled by the caller using the input pathame.
*/
char *canonicalize_dm_name(const char *ptname)
{
FILE *f;
size_t sz;
char path[PATH_MAX], name[PATH_MAX], *res = NULL;
if (!ptname || !*ptname)
return NULL;
snprintf(path, sizeof(path), "/sys/block/%s/dm/name", ptname);
if (!(f = fopen(path, "r")))
return NULL;
/* read <name>\n from sysfs */
if (fgets(name, sizeof(name), f) && (sz = strlen(name)) > 1) {
name[sz - 1] = '\0';
snprintf(path, sizeof(path), "/dev/mapper/%s", name);
if (access(path, F_OK) == 0)
res = strdup(path);
}
fclose(f);
return res;
}
/*
* Resolve a pathname to a canonical device node, e.g. /dev/sda1 or
* to a device mapper pathname.
* Returns NULL on invalid input or malloc failure; Other failures
* will be handled by the caller using the input pathame.
*/
char *canonicalize_path(const char *path)
{
char *canonical, *p;
if (!path || !*path)
return NULL;
canonical = realpath(path, NULL);
if (!canonical)
return strdup(path);
p = strrchr(canonical, '/');
if (p && strncmp(p, "/dm-", 4) == 0 && isdigit(*(p + 4))) {
char *dm = canonicalize_dm_name(p + 1);
if (dm) {
free(canonical);
return dm;
}
}
return canonical;
}
/*
* returns 1 if the device was mounted, < 0 on error or 0 if everything
* is safe to continue.
*/
int check_mounted(const char* file)
{
int fd;
int ret;
fd = open(file, O_RDONLY);
if (fd < 0) {
error("mount check: cannot open %s: %s", file,
strerror(errno));
return -errno;
}
ret = check_mounted_where(fd, file, NULL, 0, NULL);
close(fd);
return ret;
}
int check_mounted_where(int fd, const char *file, char *where, int size,
struct btrfs_fs_devices **fs_dev_ret)
{
int ret;
u64 total_devs = 1;
int is_btrfs;
struct btrfs_fs_devices *fs_devices_mnt = NULL;
FILE *f;
struct mntent *mnt;
/* scan the initial device */
ret = btrfs_scan_one_device(fd, file, &fs_devices_mnt,
&total_devs, BTRFS_SUPER_INFO_OFFSET, SBREAD_DEFAULT);
is_btrfs = (ret >= 0);
/* scan other devices */
if (is_btrfs && total_devs > 1) {
ret = btrfs_scan_devices();
if (ret)
return ret;
}
/* iterate over the list of currently mounted filesystems */
if ((f = setmntent ("/proc/self/mounts", "r")) == NULL)
return -errno;
while ((mnt = getmntent (f)) != NULL) {
if(is_btrfs) {
if(strcmp(mnt->mnt_type, "btrfs") != 0)
continue;
ret = blk_file_in_dev_list(fs_devices_mnt, mnt->mnt_fsname);
} else {
/* ignore entries in the mount table that are not
associated with a file*/
if((ret = is_existing_blk_or_reg_file(mnt->mnt_fsname)) < 0)
goto out_mntloop_err;
else if(!ret)
continue;
ret = is_same_loop_file(file, mnt->mnt_fsname);
}
if(ret < 0)
goto out_mntloop_err;
else if(ret)
break;
}
/* Did we find an entry in mnt table? */
if (mnt && size && where) {
strncpy(where, mnt->mnt_dir, size);
where[size-1] = 0;
}
if (fs_dev_ret)
*fs_dev_ret = fs_devices_mnt;
ret = (mnt != NULL);
out_mntloop_err:
endmntent (f);
return ret;
}
struct pending_dir {
struct list_head list;
char name[PATH_MAX];
};
int btrfs_register_one_device(const char *fname)
{
struct btrfs_ioctl_vol_args args;
int fd;
int ret;
fd = open("/dev/btrfs-control", O_RDWR);
if (fd < 0) {
warning(
"failed to open /dev/btrfs-control, skipping device registration: %s",
strerror(errno));
return -errno;
}
memset(&args, 0, sizeof(args));
strncpy_null(args.name, fname);
ret = ioctl(fd, BTRFS_IOC_SCAN_DEV, &args);
if (ret < 0) {
error("device scan failed on '%s': %s", fname,
strerror(errno));
ret = -errno;
}
close(fd);
return ret;
}
/*
* Register all devices in the fs_uuid list created in the user
* space. Ensure btrfs_scan_devices() is called before this func.
*/
int btrfs_register_all_devices(void)
{
int err = 0;
int ret = 0;
struct btrfs_fs_devices *fs_devices;
struct btrfs_device *device;
struct list_head *all_uuids;
all_uuids = btrfs_scanned_uuids();
list_for_each_entry(fs_devices, all_uuids, list) {
list_for_each_entry(device, &fs_devices->devices, dev_list) {
if (*device->name)
err = btrfs_register_one_device(device->name);
if (err)
ret++;
}
}
return ret;
}
int btrfs_device_already_in_root(struct btrfs_root *root, int fd,
int super_offset)
{
struct btrfs_super_block *disk_super;
char *buf;
int ret = 0;
buf = malloc(BTRFS_SUPER_INFO_SIZE);
if (!buf) {
ret = -ENOMEM;
goto out;
}
ret = pread(fd, buf, BTRFS_SUPER_INFO_SIZE, super_offset);
if (ret != BTRFS_SUPER_INFO_SIZE)
goto brelse;
ret = 0;
disk_super = (struct btrfs_super_block *)buf;
/*
* Accept devices from the same filesystem, allow partially created
* structures.
*/
if (btrfs_super_magic(disk_super) != BTRFS_MAGIC &&
btrfs_super_magic(disk_super) != BTRFS_MAGIC_PARTIAL)
goto brelse;
if (!memcmp(disk_super->fsid, root->fs_info->super_copy->fsid,
BTRFS_FSID_SIZE))
ret = 1;
brelse:
free(buf);
out:
return ret;
}
/*
* Note: this function uses a static per-thread buffer. Do not call this
* function more than 10 times within one argument list!
*/
const char *pretty_size_mode(u64 size, unsigned mode)
{
static __thread int ps_index = 0;
static __thread char ps_array[10][32];
char *ret;
ret = ps_array[ps_index];
ps_index++;
ps_index %= 10;
(void)pretty_size_snprintf(size, ret, 32, mode);
return ret;
}
static const char* unit_suffix_binary[] =
{ "B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"};
static const char* unit_suffix_decimal[] =
{ "B", "kB", "MB", "GB", "TB", "PB", "EB"};
int pretty_size_snprintf(u64 size, char *str, size_t str_size, unsigned unit_mode)
{
int num_divs;
float fraction;
u64 base = 0;
int mult = 0;
const char** suffix = NULL;
u64 last_size;
if (str_size == 0)
return 0;
if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_RAW) {
snprintf(str, str_size, "%llu", size);
return 0;
}
if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_BINARY) {
base = 1024;
mult = 1024;
suffix = unit_suffix_binary;
} else if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_DECIMAL) {
base = 1000;
mult = 1000;
suffix = unit_suffix_decimal;
}
/* Unknown mode */
if (!base) {
fprintf(stderr, "INTERNAL ERROR: unknown unit base, mode %d\n",
unit_mode);
assert(0);
return -1;
}
num_divs = 0;
last_size = size;
switch (unit_mode & UNITS_MODE_MASK) {
case UNITS_TBYTES: base *= mult; num_divs++;
case UNITS_GBYTES: base *= mult; num_divs++;
case UNITS_MBYTES: base *= mult; num_divs++;
case UNITS_KBYTES: num_divs++;
break;
case UNITS_BYTES:
base = 1;
num_divs = 0;
break;
default:
while (size >= mult) {
last_size = size;
size /= mult;
num_divs++;
}
/*
* If the value is smaller than base, we didn't do any
* division, in that case, base should be 1, not original
* base, or the unit will be wrong
*/
if (num_divs == 0)
base = 1;
}
if (num_divs >= ARRAY_SIZE(unit_suffix_binary)) {
str[0] = '\0';
printf("INTERNAL ERROR: unsupported unit suffix, index %d\n",
num_divs);
assert(0);
return -1;
}
fraction = (float)last_size / base;
return snprintf(str, str_size, "%.2f%s", fraction, suffix[num_divs]);
}
/*
* __strncpy_null - strncpy with null termination
* @dest: the target array
* @src: the source string
* @n: maximum bytes to copy (size of *dest)
*
* Like strncpy, but ensures destination is null-terminated.
*
* Copies the string pointed to by src, including the terminating null
* byte ('\0'), to the buffer pointed to by dest, up to a maximum
* of n bytes. Then ensure that dest is null-terminated.
*/
char *__strncpy_null(char *dest, const char *src, size_t n)
{
strncpy(dest, src, n);
if (n > 0)
dest[n - 1] = '\0';
return dest;
}
/*
* Checks to make sure that the label matches our requirements.
* Returns:
0 if everything is safe and usable
-1 if the label is too long
*/
static int check_label(const char *input)
{
int len = strlen(input);
if (len > BTRFS_LABEL_SIZE - 1) {
error("label %s is too long (max %d)", input,
BTRFS_LABEL_SIZE - 1);
return -1;
}
return 0;
}
static int set_label_unmounted(const char *dev, const char *label)
{
struct btrfs_trans_handle *trans;
struct btrfs_root *root;
int ret;
ret = check_mounted(dev);
if (ret < 0) {
error("checking mount status of %s failed: %d", dev, ret);
return -1;
}
if (ret > 0) {
error("device %s is mounted, use mount point", dev);
return -1;
}
/* Open the super_block at the default location
* and as read-write.
*/
root = open_ctree(dev, 0, OPEN_CTREE_WRITES);
if (!root) /* errors are printed by open_ctree() */
return -1;
trans = btrfs_start_transaction(root, 1);
__strncpy_null(root->fs_info->super_copy->label, label, BTRFS_LABEL_SIZE - 1);
btrfs_commit_transaction(trans, root);
/* Now we close it since we are done. */
close_ctree(root);
return 0;
}
static int set_label_mounted(const char *mount_path, const char *labelp)
{
int fd;
char label[BTRFS_LABEL_SIZE];
fd = open(mount_path, O_RDONLY | O_NOATIME);
if (fd < 0) {
error("unable to access %s: %s", mount_path, strerror(errno));
return -1;
}
memset(label, 0, sizeof(label));
__strncpy_null(label, labelp, BTRFS_LABEL_SIZE - 1);
if (ioctl(fd, BTRFS_IOC_SET_FSLABEL, label) < 0) {
error("unable to set label of %s: %s", mount_path,
strerror(errno));
close(fd);
return -1;
}
close(fd);
return 0;
}
int get_label_unmounted(const char *dev, char *label)
{
struct btrfs_root *root;
int ret;
ret = check_mounted(dev);
if (ret < 0) {
error("checking mount status of %s failed: %d", dev, ret);
return -1;
}
/* Open the super_block at the default location
* and as read-only.
*/
root = open_ctree(dev, 0, 0);
if(!root)
return -1;
__strncpy_null(label, root->fs_info->super_copy->label,
BTRFS_LABEL_SIZE - 1);
/* Now we close it since we are done. */
close_ctree(root);
return 0;
}
/*
* If a partition is mounted, try to get the filesystem label via its
* mounted path rather than device. Return the corresponding error
* the user specified the device path.
*/
int get_label_mounted(const char *mount_path, char *labelp)
{
char label[BTRFS_LABEL_SIZE];
int fd;
int ret;
fd = open(mount_path, O_RDONLY | O_NOATIME);
if (fd < 0) {
error("unable to access %s: %s", mount_path, strerror(errno));
return -1;
}
memset(label, '\0', sizeof(label));
ret = ioctl(fd, BTRFS_IOC_GET_FSLABEL, label);
if (ret < 0) {
if (errno != ENOTTY)
error("unable to get label of %s: %s", mount_path,
strerror(errno));
ret = -errno;
close(fd);
return ret;
}
__strncpy_null(labelp, label, BTRFS_LABEL_SIZE - 1);
close(fd);
return 0;
}
int get_label(const char *btrfs_dev, char *label)
{
int ret;
ret = is_existing_blk_or_reg_file(btrfs_dev);
if (!ret)
ret = get_label_mounted(btrfs_dev, label);
else if (ret > 0)
ret = get_label_unmounted(btrfs_dev, label);
return ret;
}
int set_label(const char *btrfs_dev, const char *label)
{
int ret;
if (check_label(label))
return -1;
ret = is_existing_blk_or_reg_file(btrfs_dev);
if (!ret)
ret = set_label_mounted(btrfs_dev, label);
else if (ret > 0)
ret = set_label_unmounted(btrfs_dev, label);
return ret;
}
/*
* A not-so-good version fls64. No fascinating optimization since
* no one except parse_size use it
*/
static int fls64(u64 x)
{
int i;
for (i = 0; i <64; i++)
if (x << i & (1ULL << 63))
return 64 - i;
return 64 - i;
}
u64 parse_size(char *s)
{
char c;
char *endptr;
u64 mult = 1;
u64 ret;
if (!s) {
error("size value is empty");
exit(1);
}
if (s[0] == '-') {
error("size value '%s' is less equal than 0", s);
exit(1);
}
ret = strtoull(s, &endptr, 10);
if (endptr == s) {
error("size value '%s' is invalid", s);
exit(1);
}
if (endptr[0] && endptr[1]) {
error("illegal suffix contains character '%c' in wrong position",
endptr[1]);
exit(1);
}
/*
* strtoll returns LLONG_MAX when overflow, if this happens,
* need to call strtoull to get the real size
*/
if (errno == ERANGE && ret == ULLONG_MAX) {
error("size value '%s' is too large for u64", s);
exit(1);
}
if (endptr[0]) {
c = tolower(endptr[0]);
switch (c) {
case 'e':
mult *= 1024;
/* fallthrough */
case 'p':
mult *= 1024;
/* fallthrough */
case 't':
mult *= 1024;
/* fallthrough */
case 'g':
mult *= 1024;
/* fallthrough */
case 'm':
mult *= 1024;
/* fallthrough */
case 'k':
mult *= 1024;
/* fallthrough */
case 'b':
break;
default:
error("unknown size descriptor '%c'", c);
exit(1);
}
}
/* Check whether ret * mult overflow */
if (fls64(ret) + fls64(mult) - 1 > 64) {
error("size value '%s' is too large for u64", s);
exit(1);
}
ret *= mult;
return ret;
}
u64 parse_qgroupid(const char *p)
{
char *s = strchr(p, '/');
const char *ptr_src_end = p + strlen(p);
char *ptr_parse_end = NULL;
u64 level;
u64 id;
int fd;
int ret = 0;
if (p[0] == '/')
goto path;
/* Numeric format like '0/257' is the primary case */
if (!s) {
id = strtoull(p, &ptr_parse_end, 10);
if (ptr_parse_end != ptr_src_end)
goto path;
return id;
}
level = strtoull(p, &ptr_parse_end, 10);
if (ptr_parse_end != s)
goto path;
id = strtoull(s + 1, &ptr_parse_end, 10);
if (ptr_parse_end != ptr_src_end)
goto path;
return (level << BTRFS_QGROUP_LEVEL_SHIFT) | id;
path:
/* Path format like subv at 'my_subvol' is the fallback case */
ret = test_issubvolume(p);
if (ret < 0 || !ret)
goto err;
fd = open(p, O_RDONLY);
if (fd < 0)
goto err;
ret = lookup_path_rootid(fd, &id);
if (ret)
error("failed to lookup root id: %s", strerror(-ret));
close(fd);
if (ret < 0)
goto err;
return id;
err:
error("invalid qgroupid or subvolume path: %s", p);
exit(-1);
}
int open_file_or_dir3(const char *fname, DIR **dirstream, int open_flags)
{
int ret;
struct stat st;
int fd;
ret = stat(fname, &st);
if (ret < 0) {
return -1;
}
if (S_ISDIR(st.st_mode)) {
*dirstream = opendir(fname);
if (!*dirstream)
return -1;
fd = dirfd(*dirstream);
} else if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)) {
fd = open(fname, open_flags);
} else {
/*
* we set this on purpose, in case the caller output
* strerror(errno) as success
*/
errno = EINVAL;
return -1;
}
if (fd < 0) {
fd = -1;
if (*dirstream) {
closedir(*dirstream);
*dirstream = NULL;
}
}
return fd;
}
int open_file_or_dir(const char *fname, DIR **dirstream)
{
return open_file_or_dir3(fname, dirstream, O_RDWR);
}
void close_file_or_dir(int fd, DIR *dirstream)
{
if (dirstream)
closedir(dirstream);
else if (fd >= 0)
close(fd);
}
int get_device_info(int fd, u64 devid,
struct btrfs_ioctl_dev_info_args *di_args)
{
int ret;
di_args->devid = devid;
memset(&di_args->uuid, '\0', sizeof(di_args->uuid));
ret = ioctl(fd, BTRFS_IOC_DEV_INFO, di_args);
return ret < 0 ? -errno : 0;
}
static u64 find_max_device_id(struct btrfs_ioctl_search_args *search_args,
int nr_items)
{
struct btrfs_dev_item *dev_item;
char *buf = search_args->buf;
buf += (nr_items - 1) * (sizeof(struct btrfs_ioctl_search_header)
+ sizeof(struct btrfs_dev_item));
buf += sizeof(struct btrfs_ioctl_search_header);
dev_item = (struct btrfs_dev_item *)buf;
return btrfs_stack_device_id(dev_item);
}
static int search_chunk_tree_for_fs_info(int fd,
struct btrfs_ioctl_fs_info_args *fi_args)
{
int ret;
int max_items;
u64 start_devid = 1;
struct btrfs_ioctl_search_args search_args;
struct btrfs_ioctl_search_key *search_key = &search_args.key;
fi_args->num_devices = 0;
max_items = BTRFS_SEARCH_ARGS_BUFSIZE
/ (sizeof(struct btrfs_ioctl_search_header)
+ sizeof(struct btrfs_dev_item));
search_key->tree_id = BTRFS_CHUNK_TREE_OBJECTID;
search_key->min_objectid = BTRFS_DEV_ITEMS_OBJECTID;
search_key->max_objectid = BTRFS_DEV_ITEMS_OBJECTID;
search_key->min_type = BTRFS_DEV_ITEM_KEY;
search_key->max_type = BTRFS_DEV_ITEM_KEY;
search_key->min_transid = 0;
search_key->max_transid = (u64)-1;
search_key->nr_items = max_items;
search_key->max_offset = (u64)-1;
again:
search_key->min_offset = start_devid;
ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &search_args);
if (ret < 0)
return -errno;
fi_args->num_devices += (u64)search_key->nr_items;
if (search_key->nr_items == max_items) {
start_devid = find_max_device_id(&search_args,
search_key->nr_items) + 1;
goto again;
}
/* get the lastest max_id to stay consistent with the num_devices */
if (search_key->nr_items == 0)
/*
* last tree_search returns an empty buf, use the devid of
* the last dev_item of the previous tree_search
*/
fi_args->max_id = start_devid - 1;
else
fi_args->max_id = find_max_device_id(&search_args,
search_key->nr_items);
return 0;
}
/*
* For a given path, fill in the ioctl fs_ and info_ args.
* If the path is a btrfs mountpoint, fill info for all devices.
* If the path is a btrfs device, fill in only that device.
*
* The path provided must be either on a mounted btrfs fs,
* or be a mounted btrfs device.
*
* Returns 0 on success, or a negative errno.
*/
int get_fs_info(const char *path, struct btrfs_ioctl_fs_info_args *fi_args,
struct btrfs_ioctl_dev_info_args **di_ret)
{
int fd = -1;
int ret = 0;
int ndevs = 0;
int i = 0;
int replacing = 0;
struct btrfs_fs_devices *fs_devices_mnt = NULL;
struct btrfs_ioctl_dev_info_args *di_args;
struct btrfs_ioctl_dev_info_args tmp;
char mp[PATH_MAX];
DIR *dirstream = NULL;
memset(fi_args, 0, sizeof(*fi_args));
if (is_block_device(path) == 1) {
struct btrfs_super_block *disk_super;
char buf[BTRFS_SUPER_INFO_SIZE];
u64 devid;
/* Ensure it's mounted, then set path to the mountpoint */
fd = open(path, O_RDONLY);
if (fd < 0) {
ret = -errno;
error("cannot open %s: %s", path, strerror(errno));
goto out;
}
ret = check_mounted_where(fd, path, mp, sizeof(mp),
&fs_devices_mnt);
if (!ret) {
ret = -EINVAL;
goto out;
}
if (ret < 0)
goto out;
path = mp;
/* Only fill in this one device */
fi_args->num_devices = 1;
disk_super = (struct btrfs_super_block *)buf;
ret = btrfs_read_dev_super(fd, disk_super,
BTRFS_SUPER_INFO_OFFSET, 0);
if (ret < 0) {
ret = -EIO;
goto out;
}
devid = btrfs_stack_device_id(&disk_super->dev_item);
fi_args->max_id = devid;
i = devid;
memcpy(fi_args->fsid, fs_devices_mnt->fsid, BTRFS_FSID_SIZE);
close(fd);
}
/* at this point path must not be for a block device */
fd = open_file_or_dir(path, &dirstream);
if (fd < 0) {
ret = -errno;
goto out;
}
/* fill in fi_args if not just a single device */
if (fi_args->num_devices != 1) {
ret = ioctl(fd, BTRFS_IOC_FS_INFO, fi_args);
if (ret < 0) {
ret = -errno;
goto out;
}
/*
* The fs_args->num_devices does not include seed devices
*/
ret = search_chunk_tree_for_fs_info(fd, fi_args);
if (ret)
goto out;
/*
* search_chunk_tree_for_fs_info() will lacks the devid 0
* so manual probe for it here.
*/
ret = get_device_info(fd, 0, &tmp);
if (!ret) {
fi_args->num_devices++;
ndevs++;
replacing = 1;
if (i == 0)
i++;
}
}
if (!fi_args->num_devices)
goto out;
di_args = *di_ret = malloc((fi_args->num_devices) * sizeof(*di_args));
if (!di_args) {
ret = -errno;
goto out;
}
if (replacing)
memcpy(di_args, &tmp, sizeof(tmp));
for (; i <= fi_args->max_id; ++i) {
ret = get_device_info(fd, i, &di_args[ndevs]);
if (ret == -ENODEV)
continue;
if (ret)
goto out;
ndevs++;
}
/*
* only when the only dev we wanted to find is not there then
* let any error be returned
*/
if (fi_args->num_devices != 1) {
BUG_ON(ndevs == 0);
ret = 0;
}
out:
close_file_or_dir(fd, dirstream);
return ret;
}
#define isoctal(c) (((c) & ~7) == '0')
static inline void translate(char *f, char *t)
{
while (*f != '\0') {
if (*f == '\\' &&
isoctal(f[1]) && isoctal(f[2]) && isoctal(f[3])) {
*t++ = 64*(f[1] & 7) + 8*(f[2] & 7) + (f[3] & 7);
f += 4;
} else
*t++ = *f++;
}
*t = '\0';
return;
}
/*
* Checks if the swap device.
* Returns 1 if swap device, < 0 on error or 0 if not swap device.
*/
static int is_swap_device(const char *file)
{
FILE *f;
struct stat st_buf;
dev_t dev;
ino_t ino = 0;
char tmp[PATH_MAX];
char buf[PATH_MAX];
char *cp;
int ret = 0;
if (stat(file, &st_buf) < 0)
return -errno;
if (S_ISBLK(st_buf.st_mode))
dev = st_buf.st_rdev;
else if (S_ISREG(st_buf.st_mode)) {
dev = st_buf.st_dev;
ino = st_buf.st_ino;
} else
return 0;
if ((f = fopen("/proc/swaps", "r")) == NULL)
return 0;
/* skip the first line */
if (fgets(tmp, sizeof(tmp), f) == NULL)
goto out;
while (fgets(tmp, sizeof(tmp), f) != NULL) {
if ((cp = strchr(tmp, ' ')) != NULL)
*cp = '\0';
if ((cp = strchr(tmp, '\t')) != NULL)
*cp = '\0';
translate(tmp, buf);
if (stat(buf, &st_buf) != 0)
continue;
if (S_ISBLK(st_buf.st_mode)) {
if (dev == st_buf.st_rdev) {
ret = 1;
break;
}
} else if (S_ISREG(st_buf.st_mode)) {
if (dev == st_buf.st_dev && ino == st_buf.st_ino) {
ret = 1;
break;
}
}
}
out:
fclose(f);
return ret;
}
/*
* Check for existing filesystem or partition table on device.
* Returns:
* 1 for existing fs or partition
* 0 for nothing found
* -1 for internal error
*/
static int check_overwrite(const char *device)
{
const char *type;
blkid_probe pr = NULL;
int ret;
blkid_loff_t size;
if (!device || !*device)
return 0;
ret = -1; /* will reset on success of all setup calls */
pr = blkid_new_probe_from_filename(device);
if (!pr)
goto out;
size = blkid_probe_get_size(pr);
if (size < 0)
goto out;
/* nothing to overwrite on a 0-length device */
if (size == 0) {
ret = 0;
goto out;
}
ret = blkid_probe_enable_partitions(pr, 1);
if (ret < 0)
goto out;
ret = blkid_do_fullprobe(pr);
if (ret < 0)
goto out;
/*
* Blkid returns 1 for nothing found and 0 when it finds a signature,
* but we want the exact opposite, so reverse the return value here.
*
* In addition print some useful diagnostics about what actually is
* on the device.
*/
if (ret) {
ret = 0;
goto out;
}
if (!blkid_probe_lookup_value(pr, "TYPE", &type, NULL)) {
fprintf(stderr,
"%s appears to contain an existing "
"filesystem (%s).\n", device, type);
} else if (!blkid_probe_lookup_value(pr, "PTTYPE", &type, NULL)) {
fprintf(stderr,
"%s appears to contain a partition "
"table (%s).\n", device, type);
} else {
fprintf(stderr,
"%s appears to contain something weird "
"according to blkid\n", device);
}
ret = 1;
out:
if (pr)
blkid_free_probe(pr);
if (ret == -1)
fprintf(stderr,
"probe of %s failed, cannot detect "
"existing filesystem.\n", device);
return ret;
}
static int group_profile_devs_min(u64 flag)
{
switch (flag & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
case 0: /* single */
case BTRFS_BLOCK_GROUP_DUP:
return 1;
case BTRFS_BLOCK_GROUP_RAID0:
case BTRFS_BLOCK_GROUP_RAID1:
case BTRFS_BLOCK_GROUP_RAID5:
return 2;
case BTRFS_BLOCK_GROUP_RAID6:
return 3;
case BTRFS_BLOCK_GROUP_RAID10:
return 4;
default:
return -1;
}
}
int test_num_disk_vs_raid(u64 metadata_profile, u64 data_profile,
u64 dev_cnt, int mixed, int ssd)
{
u64 allowed = 0;
u64 profile = metadata_profile | data_profile;
switch (dev_cnt) {
default:
case 4:
allowed |= BTRFS_BLOCK_GROUP_RAID10;
case 3:
allowed |= BTRFS_BLOCK_GROUP_RAID6;
case 2:
allowed |= BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
BTRFS_BLOCK_GROUP_RAID5;
case 1:
allowed |= BTRFS_BLOCK_GROUP_DUP;
}
if (dev_cnt > 1 && profile & BTRFS_BLOCK_GROUP_DUP) {
warning("DUP is not recommended on filesystem with multiple devices");
}
if (metadata_profile & ~allowed) {
fprintf(stderr,
"ERROR: unable to create FS with metadata profile %s "
"(have %llu devices but %d devices are required)\n",
btrfs_group_profile_str(metadata_profile), dev_cnt,
group_profile_devs_min(metadata_profile));
return 1;
}
if (data_profile & ~allowed) {
fprintf(stderr,
"ERROR: unable to create FS with data profile %s "
"(have %llu devices but %d devices are required)\n",
btrfs_group_profile_str(data_profile), dev_cnt,
group_profile_devs_min(data_profile));
return 1;
}
if (dev_cnt == 3 && profile & BTRFS_BLOCK_GROUP_RAID6) {
warning("RAID6 is not recommended on filesystem with 3 devices only");
}
if (dev_cnt == 2 && profile & BTRFS_BLOCK_GROUP_RAID5) {
warning("RAID5 is not recommended on filesystem with 2 devices only");
}
warning_on(!mixed && (data_profile & BTRFS_BLOCK_GROUP_DUP) && ssd,
"DUP may not actually lead to 2 copies on the device, see manual page");
return 0;
}
int group_profile_max_safe_loss(u64 flags)
{
switch (flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
case 0: /* single */
case BTRFS_BLOCK_GROUP_DUP:
case BTRFS_BLOCK_GROUP_RAID0:
return 0;
case BTRFS_BLOCK_GROUP_RAID1:
case BTRFS_BLOCK_GROUP_RAID5:
case BTRFS_BLOCK_GROUP_RAID10:
return 1;
case BTRFS_BLOCK_GROUP_RAID6:
return 2;
default:
return -1;
}
}
/*
* Check if a device is suitable for btrfs
* returns:
* 1: something is wrong, an error is printed
* 0: all is fine
*/
int test_dev_for_mkfs(const char *file, int force_overwrite)
{
int ret, fd;
struct stat st;
ret = is_swap_device(file);
if (ret < 0) {
error("checking status of %s: %s", file, strerror(-ret));
return 1;
}
if (ret == 1) {
error("%s is a swap device", file);
return 1;
}
if (!force_overwrite) {
if (check_overwrite(file)) {
error("use the -f option to force overwrite of %s",
file);
return 1;
}
}
ret = check_mounted(file);
if (ret < 0) {
error("cannot check mount status of %s: %s", file,
strerror(-ret));
return 1;
}
if (ret == 1) {
error("%s is mounted", file);
return 1;
}
/* check if the device is busy */
fd = open(file, O_RDWR|O_EXCL);
if (fd < 0) {
error("unable to open %s: %s", file, strerror(errno));
return 1;
}
if (fstat(fd, &st)) {
error("unable to stat %s: %s", file, strerror(errno));
close(fd);
return 1;
}
if (!S_ISBLK(st.st_mode)) {
error("%s is not a block device", file);
close(fd);
return 1;
}
close(fd);
return 0;
}
int btrfs_scan_devices(void)
{
int fd = -1;
int ret;
u64 num_devices;
struct btrfs_fs_devices *tmp_devices;
blkid_dev_iterate iter = NULL;
blkid_dev dev = NULL;
blkid_cache cache = NULL;
char path[PATH_MAX];
if (btrfs_scan_done)
return 0;
if (blkid_get_cache(&cache, NULL) < 0) {
error("blkid cache get failed");
return 1;
}
blkid_probe_all(cache);
iter = blkid_dev_iterate_begin(cache);
blkid_dev_set_search(iter, "TYPE", "btrfs");
while (blkid_dev_next(iter, &dev) == 0) {
dev = blkid_verify(cache, dev);
if (!dev)
continue;
/* if we are here its definitely a btrfs disk*/
strncpy_null(path, blkid_dev_devname(dev));
fd = open(path, O_RDONLY);
if (fd < 0) {
error("cannot open %s: %s", path, strerror(errno));
continue;
}
ret = btrfs_scan_one_device(fd, path, &tmp_devices,
&num_devices, BTRFS_SUPER_INFO_OFFSET,
SBREAD_DEFAULT);
if (ret) {
error("cannot scan %s: %s", path, strerror(-ret));
close (fd);
continue;
}
close(fd);
}
blkid_dev_iterate_end(iter);
blkid_put_cache(cache);
btrfs_scan_done = 1;
return 0;
}
int is_vol_small(const char *file)
{
int fd = -1;
int e;
struct stat st;
u64 size;
fd = open(file, O_RDONLY);
if (fd < 0)
return -errno;
if (fstat(fd, &st) < 0) {
e = -errno;
close(fd);
return e;
}
size = btrfs_device_size(fd, &st);
if (size == 0) {
close(fd);
return -1;
}
if (size < BTRFS_MKFS_SMALL_VOLUME_SIZE) {
close(fd);
return 1;
} else {
close(fd);
return 0;
}
}
/*
* This reads a line from the stdin and only returns non-zero if the
* first whitespace delimited token is a case insensitive match with yes
* or y.
*/
int ask_user(const char *question)
{
char buf[30] = {0,};
char *saveptr = NULL;
char *answer;
printf("%s [y/N]: ", question);
return fgets(buf, sizeof(buf) - 1, stdin) &&
(answer = strtok_r(buf, " \t\n\r", &saveptr)) &&
(!strcasecmp(answer, "yes") || !strcasecmp(answer, "y"));
}
/*
* For a given:
* - file or directory return the containing tree root id
* - subvolume return its own tree id
* - BTRFS_EMPTY_SUBVOL_DIR_OBJECTID (directory with ino == 2) the result is
* undefined and function returns -1
*/
int lookup_path_rootid(int fd, u64 *rootid)
{
struct btrfs_ioctl_ino_lookup_args args;
int ret;
memset(&args, 0, sizeof(args));
args.treeid = 0;
args.objectid = BTRFS_FIRST_FREE_OBJECTID;
ret = ioctl(fd, BTRFS_IOC_INO_LOOKUP, &args);
if (ret < 0)
return -errno;
*rootid = args.treeid;
return 0;
}
/*
* return 0 if a btrfs mount point is found
* return 1 if a mount point is found but not btrfs
* return <0 if something goes wrong
*/
int find_mount_root(const char *path, char **mount_root)
{
FILE *mnttab;
int fd;
struct mntent *ent;
int len;
int ret;
int not_btrfs = 1;
int longest_matchlen = 0;
char *longest_match = NULL;
fd = open(path, O_RDONLY | O_NOATIME);
if (fd < 0)
return -errno;
close(fd);
mnttab = setmntent("/proc/self/mounts", "r");
if (!mnttab)
return -errno;
while ((ent = getmntent(mnttab))) {
len = strlen(ent->mnt_dir);
if (strncmp(ent->mnt_dir, path, len) == 0) {
/* match found and use the latest match */
if (longest_matchlen <= len) {
free(longest_match);
longest_matchlen = len;
longest_match = strdup(ent->mnt_dir);
not_btrfs = strcmp(ent->mnt_type, "btrfs");
}
}
}
endmntent(mnttab);
if (!longest_match)
return -ENOENT;
if (not_btrfs) {
free(longest_match);
return 1;
}
ret = 0;
*mount_root = realpath(longest_match, NULL);
if (!*mount_root)
ret = -errno;
free(longest_match);
return ret;
}
int test_minimum_size(const char *file, u32 nodesize)
{
int fd;
struct stat statbuf;
fd = open(file, O_RDONLY);
if (fd < 0)
return -errno;
if (stat(file, &statbuf) < 0) {
close(fd);
return -errno;
}
if (btrfs_device_size(fd, &statbuf) < btrfs_min_dev_size(nodesize)) {
close(fd);
return 1;
}
close(fd);
return 0;
}
/*
* Test if path is a directory
* Returns:
* 0 - path exists but it is not a directory
* 1 - path exists and it is a directory
* < 0 - error
*/
int test_isdir(const char *path)
{
struct stat st;
int ret;
ret = stat(path, &st);
if (ret < 0)
return -errno;
return !!S_ISDIR(st.st_mode);
}
void units_set_mode(unsigned *units, unsigned mode)
{
unsigned base = *units & UNITS_MODE_MASK;
*units = base | mode;
}
void units_set_base(unsigned *units, unsigned base)
{
unsigned mode = *units & ~UNITS_MODE_MASK;
*units = base | mode;
}
int find_next_key(struct btrfs_path *path, struct btrfs_key *key)
{
int level;
for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
if (!path->nodes[level])
break;
if (path->slots[level] + 1 >=
btrfs_header_nritems(path->nodes[level]))
continue;
if (level == 0)
btrfs_item_key_to_cpu(path->nodes[level], key,
path->slots[level] + 1);
else
btrfs_node_key_to_cpu(path->nodes[level], key,
path->slots[level] + 1);
return 0;
}
return 1;
}
const char* btrfs_group_type_str(u64 flag)
{
u64 mask = BTRFS_BLOCK_GROUP_TYPE_MASK |
BTRFS_SPACE_INFO_GLOBAL_RSV;
switch (flag & mask) {
case BTRFS_BLOCK_GROUP_DATA:
return "Data";
case BTRFS_BLOCK_GROUP_SYSTEM:
return "System";
case BTRFS_BLOCK_GROUP_METADATA:
return "Metadata";
case BTRFS_BLOCK_GROUP_DATA|BTRFS_BLOCK_GROUP_METADATA:
return "Data+Metadata";
case BTRFS_SPACE_INFO_GLOBAL_RSV:
return "GlobalReserve";
default:
return "unknown";
}
}
const char* btrfs_group_profile_str(u64 flag)
{
switch (flag & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
case 0:
return "single";
case BTRFS_BLOCK_GROUP_RAID0:
return "RAID0";
case BTRFS_BLOCK_GROUP_RAID1:
return "RAID1";
case BTRFS_BLOCK_GROUP_RAID5:
return "RAID5";
case BTRFS_BLOCK_GROUP_RAID6:
return "RAID6";
case BTRFS_BLOCK_GROUP_DUP:
return "DUP";
case BTRFS_BLOCK_GROUP_RAID10:
return "RAID10";
default:
return "unknown";
}
}
u64 disk_size(const char *path)
{
struct statfs sfs;
if (statfs(path, &sfs) < 0)
return 0;
else
return sfs.f_bsize * sfs.f_blocks;
}
u64 get_partition_size(const char *dev)
{
u64 result;
int fd = open(dev, O_RDONLY);
if (fd < 0)
return 0;
if (ioctl(fd, BLKGETSIZE64, &result) < 0) {
close(fd);
return 0;
}
close(fd);
return result;
}
int btrfs_tree_search2_ioctl_supported(int fd)
{
struct btrfs_ioctl_search_args_v2 *args2;
struct btrfs_ioctl_search_key *sk;
int args2_size = 1024;
char args2_buf[args2_size];
int ret;
static int v2_supported = -1;
if (v2_supported != -1)
return v2_supported;
args2 = (struct btrfs_ioctl_search_args_v2 *)args2_buf;
sk = &(args2->key);
/*
* Search for the extent tree item in the root tree.
*/
sk->tree_id = BTRFS_ROOT_TREE_OBJECTID;
sk->min_objectid = BTRFS_EXTENT_TREE_OBJECTID;
sk->max_objectid = BTRFS_EXTENT_TREE_OBJECTID;
sk->min_type = BTRFS_ROOT_ITEM_KEY;
sk->max_type = BTRFS_ROOT_ITEM_KEY;
sk->min_offset = 0;
sk->max_offset = (u64)-1;
sk->min_transid = 0;
sk->max_transid = (u64)-1;
sk->nr_items = 1;
args2->buf_size = args2_size - sizeof(struct btrfs_ioctl_search_args_v2);
ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH_V2, args2);
if (ret == -EOPNOTSUPP)
v2_supported = 0;
else if (ret == 0)
v2_supported = 1;
else
return ret;
return v2_supported;
}
int btrfs_check_nodesize(u32 nodesize, u32 sectorsize, u64 features)
{
if (nodesize < sectorsize) {
error("illegal nodesize %u (smaller than %u)",
nodesize, sectorsize);
return -1;
} else if (nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
error("illegal nodesize %u (larger than %u)",
nodesize, BTRFS_MAX_METADATA_BLOCKSIZE);
return -1;
} else if (nodesize & (sectorsize - 1)) {
error("illegal nodesize %u (not aligned to %u)",
nodesize, sectorsize);
return -1;
} else if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS &&
nodesize != sectorsize) {
error("illegal nodesize %u (not equal to %u for mixed block group)",
nodesize, sectorsize);
return -1;
}
return 0;
}
/*
* Copy a path argument from SRC to DEST and check the SRC length if it's at
* most PATH_MAX and fits into DEST. DESTLEN is supposed to be exact size of
* the buffer.
* The destination buffer is zero terminated.
* Return < 0 for error, 0 otherwise.
*/
int arg_copy_path(char *dest, const char *src, int destlen)
{
size_t len = strlen(src);
if (len >= PATH_MAX || len >= destlen)
return -ENAMETOOLONG;
__strncpy_null(dest, src, destlen);
return 0;
}
unsigned int get_unit_mode_from_arg(int *argc, char *argv[], int df_mode)
{
unsigned int unit_mode = UNITS_DEFAULT;
int arg_i;
int arg_end;
for (arg_i = 0; arg_i < *argc; arg_i++) {
if (!strcmp(argv[arg_i], "--"))
break;
if (!strcmp(argv[arg_i], "--raw")) {
unit_mode = UNITS_RAW;
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "--human-readable")) {
unit_mode = UNITS_HUMAN_BINARY;
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "--iec")) {
units_set_mode(&unit_mode, UNITS_BINARY);
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "--si")) {
units_set_mode(&unit_mode, UNITS_DECIMAL);
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "--kbytes")) {
units_set_base(&unit_mode, UNITS_KBYTES);
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "--mbytes")) {
units_set_base(&unit_mode, UNITS_MBYTES);
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "--gbytes")) {
units_set_base(&unit_mode, UNITS_GBYTES);
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "--tbytes")) {
units_set_base(&unit_mode, UNITS_TBYTES);
argv[arg_i] = NULL;
continue;
}
if (!df_mode)
continue;
if (!strcmp(argv[arg_i], "-b")) {
unit_mode = UNITS_RAW;
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "-h")) {
unit_mode = UNITS_HUMAN_BINARY;
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "-H")) {
unit_mode = UNITS_HUMAN_DECIMAL;
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "-k")) {
units_set_base(&unit_mode, UNITS_KBYTES);
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "-m")) {
units_set_base(&unit_mode, UNITS_MBYTES);
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "-g")) {
units_set_base(&unit_mode, UNITS_GBYTES);
argv[arg_i] = NULL;
continue;
}
if (!strcmp(argv[arg_i], "-t")) {
units_set_base(&unit_mode, UNITS_TBYTES);
argv[arg_i] = NULL;
continue;
}
}
for (arg_i = 0, arg_end = 0; arg_i < *argc; arg_i++) {
if (!argv[arg_i])
continue;
argv[arg_end] = argv[arg_i];
arg_end++;
}
*argc = arg_end;
return unit_mode;
}
int string_is_numerical(const char *str)
{
if (!(*str >= '0' && *str <= '9'))
return 0;
while (*str >= '0' && *str <= '9')
str++;
if (*str != '\0')
return 0;
return 1;
}
/*
* Preprocess @argv with getopt_long to reorder options and consume the "--"
* option separator.
* Unknown short and long options are reported, optionally the @usage is printed
* before exit.
*/
void clean_args_no_options(int argc, char *argv[], const char * const *usagestr)
{
static const struct option long_options[] = {
{NULL, 0, NULL, 0}
};
while (1) {
int c = getopt_long(argc, argv, "", long_options, NULL);
if (c < 0)
break;
switch (c) {
default:
if (usagestr)
usage(usagestr);
}
}
}
/*
* Same as clean_args_no_options but pass through arguments that could look
* like short options. Eg. reisze which takes a negative resize argument like
* '-123M' .
*
* This accepts only two forms:
* - "-- option1 option2 ..."
* - "option1 option2 ..."
*/
void clean_args_no_options_relaxed(int argc, char *argv[], const char * const *usagestr)
{
if (argc <= 1)
return;
if (strcmp(argv[1], "--") == 0)
optind = 2;
}
/* Subvolume helper functions */
/*
* test if name is a correct subvolume name
* this function return
* 0-> name is not a correct subvolume name
* 1-> name is a correct subvolume name
*/
int test_issubvolname(const char *name)
{
return name[0] != '\0' && !strchr(name, '/') &&
strcmp(name, ".") && strcmp(name, "..");
}
/*
* Test if path is a subvolume
* Returns:
* 0 - path exists but it is not a subvolume
* 1 - path exists and it is a subvolume
* < 0 - error
*/
int test_issubvolume(const char *path)
{
struct stat st;
struct statfs stfs;
int res;
res = stat(path, &st);
if (res < 0)
return -errno;
if (st.st_ino != BTRFS_FIRST_FREE_OBJECTID || !S_ISDIR(st.st_mode))
return 0;
res = statfs(path, &stfs);
if (res < 0)
return -errno;
return (int)stfs.f_type == BTRFS_SUPER_MAGIC;
}
const char *subvol_strip_mountpoint(const char *mnt, const char *full_path)
{
int len = strlen(mnt);
if (!len)
return full_path;
if (mnt[len - 1] != '/')
len += 1;
return full_path + len;
}
/*
* Returns
* <0: Std error
* 0: All fine
* 1: Error; and error info printed to the terminal. Fixme.
* 2: If the fullpath is root tree instead of subvol tree
*/
int get_subvol_info(const char *fullpath, struct root_info *get_ri)
{
u64 sv_id;
int ret = 1;
int fd = -1;
int mntfd = -1;
char *mnt = NULL;
const char *svpath = NULL;
DIR *dirstream1 = NULL;
DIR *dirstream2 = NULL;
ret = test_issubvolume(fullpath);
if (ret < 0)
return ret;
if (!ret) {
error("not a subvolume: %s", fullpath);
return 1;
}
ret = find_mount_root(fullpath, &mnt);
if (ret < 0)
return ret;
if (ret > 0) {
error("%s doesn't belong to btrfs mount point", fullpath);
return 1;
}
ret = 1;
svpath = subvol_strip_mountpoint(mnt, fullpath);
fd = btrfs_open_dir(fullpath, &dirstream1, 1);
if (fd < 0)
goto out;
ret = btrfs_list_get_path_rootid(fd, &sv_id);
if (ret)
goto out;
mntfd = btrfs_open_dir(mnt, &dirstream2, 1);
if (mntfd < 0)
goto out;
if (sv_id == BTRFS_FS_TREE_OBJECTID) {
ret = 2;
/*
* So that caller may decide if thats an error or just fine.
*/
goto out;
}
memset(get_ri, 0, sizeof(*get_ri));
get_ri->root_id = sv_id;
ret = btrfs_get_subvol(mntfd, get_ri);
if (ret)
error("can't find '%s': %d", svpath, ret);
out:
close_file_or_dir(mntfd, dirstream2);
close_file_or_dir(fd, dirstream1);
free(mnt);
return ret;
}
void init_rand_seed(u64 seed)
{
int i;
/* only use the last 48 bits */
for (i = 0; i < 3; i++) {
rand_seed[i] = (unsigned short)(seed ^ (unsigned short)(-1));
seed >>= 16;
}
rand_seed_initlized = 1;
}
static void __init_seed(void)
{
struct timeval tv;
int ret;
int fd;
if(rand_seed_initlized)
return;
/* Use urandom as primary seed source. */
fd = open("/dev/urandom", O_RDONLY);
if (fd >= 0) {
ret = read(fd, rand_seed, sizeof(rand_seed));
close(fd);
if (ret < sizeof(rand_seed))
goto fallback;
} else {
fallback:
/* Use time and pid as fallback seed */
warning("failed to read /dev/urandom, use time and pid as random seed");
gettimeofday(&tv, 0);
rand_seed[0] = getpid() ^ (tv.tv_sec & 0xFFFF);
rand_seed[1] = getppid() ^ (tv.tv_usec & 0xFFFF);
rand_seed[2] = (tv.tv_sec ^ tv.tv_usec) >> 16;
}
rand_seed_initlized = 1;
}
u32 rand_u32(void)
{
__init_seed();
/*
* Don't use nrand48, its range is [0,2^31) The highest bit will alwasy
* be 0. Use jrand48 to include the highest bit.
*/
return (u32)jrand48(rand_seed);
}
unsigned int rand_range(unsigned int upper)
{
__init_seed();
/*
* Use the full 48bits to mod, which would be more uniformly
* distributed
*/
return (unsigned int)(jrand48(rand_seed) % upper);
}
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