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btrfs-progs/common/utils.c

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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 <sys/sysinfo.h>
#include <uuid/uuid.h>
#include <fcntl.h>
#include <unistd.h>
#include <mntent.h>
#include <ctype.h>
#include <limits.h>
#include <blkid/blkid.h>
#include <sys/vfs.h>
#include <sys/statfs.h>
#include <linux/magic.h>
#include <getopt.h>
#include <btrfsutil.h>
#include "kerncompat.h"
#include "kernel-lib/radix-tree.h"
#include "kernel-shared/ctree.h"
#include "kernel-shared/disk-io.h"
#include "kernel-shared/transaction.h"
#include "crypto/crc32c.h"
#include "common/utils.h"
#include "common/path-utils.h"
#include "common/device-scan.h"
#include "kernel-shared/volumes.h"
#include "ioctl.h"
#include "cmds/commands.h"
#include "mkfs/common.h"
static int rand_seed_initialized = 0;
static unsigned short rand_seed[3];
struct btrfs_config bconf;
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->fs_info->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, now);
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;
}
/*
* 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 = path_is_block_device(dev);
if (ret <= 0) {
if (!ret) {
error("not a block device: %s", dev);
ret = -EINVAL;
} else {
errno = -ret;
error("cannot check %s: %m", dev);
}
goto out;
}
fd = open(dev, O_RDONLY);
if (fd < 0) {
ret = -errno;
error("cannot open %s: %m", dev);
goto out;
}
ret = check_mounted_where(fd, dev, mp, mp_size, NULL, SBREAD_DEFAULT);
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 (path_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': %m",
path);
} 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 if dir_only is 1
*/
int btrfs_open(const char *path, DIR **dirstream, int verbose, int dir_only)
{
struct statfs stfs;
struct stat st;
int ret;
if (stat(path, &st) != 0) {
error_on(verbose, "cannot access '%s': %m", path);
return -1;
}
if (dir_only && !S_ISDIR(st.st_mode)) {
error_on(verbose, "not a directory: %s", path);
return -3;
}
if (statfs(path, &stfs) != 0) {
error_on(verbose, "cannot access '%s': %m", path);
return -1;
}
if (stfs.f_type != BTRFS_SUPER_MAGIC) {
error_on(verbose, "not a btrfs filesystem: %s", path);
return -2;
}
ret = open_file_or_dir(path, dirstream);
if (ret < 0) {
error_on(verbose, "cannot access '%s': %m", path);
}
return ret;
}
int btrfs_open_dir(const char *path, DIR **dirstream, int verbose)
{
return btrfs_open(path, dirstream, verbose, 1);
}
int btrfs_open_file_or_dir(const char *path, DIR **dirstream, int verbose)
{
return btrfs_open(path, dirstream, verbose, 0);
}
/* 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 btrfs_device *device;
list_for_each_entry(device, &fs_devices->devices, dev_list) {
if((ret = is_same_loop_file(device->name, file)))
return ret;
}
return 0;
}
/*
* 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: %m", file);
return -errno;
}
ret = check_mounted_where(fd, file, NULL, 0, NULL, SBREAD_DEFAULT);
close(fd);
return ret;
}
int check_mounted_where(int fd, const char *file, char *where, int size,
struct btrfs_fs_devices **fs_dev_ret, unsigned sbflags)
{
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, sbflags);
is_btrfs = (ret >= 0);
/* scan other devices */
if (is_btrfs && total_devs > 1) {
ret = btrfs_scan_devices(0);
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 = path_is_reg_or_block_device(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];
};
/*
* 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;
int negative;
if (str_size == 0)
return 0;
negative = !!(unit_mode & UNITS_NEGATIVE);
unit_mode &= ~UNITS_NEGATIVE;
if ((unit_mode & ~UNITS_MODE_MASK) == UNITS_RAW) {
if (negative)
snprintf(str, str_size, "%lld", size);
else
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 %u\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++;
/* fallthrough */
case UNITS_GBYTES:
base *= mult;
num_divs++;
/* fallthrough */
case UNITS_MBYTES:
base *= mult;
num_divs++;
/* fallthrough */
case UNITS_KBYTES:
num_divs++;
break;
case UNITS_BYTES:
base = 1;
num_divs = 0;
break;
default:
if (negative) {
s64 ssize = (s64)size;
s64 last_ssize = ssize;
while ((ssize < 0 ? -ssize : ssize) >= mult) {
last_ssize = ssize;
ssize /= mult;
num_divs++;
}
last_size = (u64)last_ssize;
} else {
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;
}
if (negative) {
fraction = (float)(s64)last_size / base;
} else {
fraction = (float)last_size / base;
}
return snprintf(str, str_size, "%.2f%s", fraction, suffix[num_divs]);
}
/*
* 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);
BUG_ON(IS_ERR(trans));
__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: %m", mount_path);
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: %m", mount_path);
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: %m", mount_path);
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: %m", mount_path);
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 = path_is_reg_or_block_device(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 = path_is_reg_or_block_device(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_from_string uses 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_from_string(const 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;
enum btrfs_util_error err;
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 */
err = btrfs_util_is_subvolume(p);
if (err)
goto err;
fd = open(p, O_RDONLY);
if (fd < 0)
goto err;
ret = lookup_path_rootid(fd, &id);
if (ret) {
errno = -ret;
error("failed to lookup root id: %m");
}
close(fd);
if (ret < 0)
goto err;
return id;
err:
error("invalid qgroupid or subvolume path: %s", p);
exit(-1);
}
enum btrfs_csum_type parse_csum_type(const char *s)
{
if (strcasecmp(s, "crc32c") == 0) {
return BTRFS_CSUM_TYPE_CRC32;
} else if (strcasecmp(s, "xxhash64") == 0 ||
strcasecmp(s, "xxhash") == 0) {
return BTRFS_CSUM_TYPE_XXHASH;
} else if (strcasecmp(s, "sha256") == 0) {
return BTRFS_CSUM_TYPE_SHA256;
} else if (strcasecmp(s, "blake2b") == 0 ||
strcasecmp(s, "blake2") == 0) {
return BTRFS_CSUM_TYPE_BLAKE2;
} else {
error("unknown csum type %s", s);
exit(1);
}
/* not reached */
return 0;
}
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)
{
int old_errno;
old_errno = errno;
if (dirstream) {
closedir(dirstream);
} else if (fd >= 0) {
close(fd);
}
errno = old_errno;
}
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;
}
int get_df(int fd, struct btrfs_ioctl_space_args **sargs_ret)
{
u64 count = 0;
int ret;
struct btrfs_ioctl_space_args *sargs;
sargs = malloc(sizeof(struct btrfs_ioctl_space_args));
if (!sargs)
return -ENOMEM;
sargs->space_slots = 0;
sargs->total_spaces = 0;
ret = ioctl(fd, BTRFS_IOC_SPACE_INFO, sargs);
if (ret < 0) {
error("cannot get space info: %m");
free(sargs);
return -errno;
}
/* This really should never happen */
if (!sargs->total_spaces) {
free(sargs);
return -ENOENT;
}
count = sargs->total_spaces;
free(sargs);
sargs = malloc(sizeof(struct btrfs_ioctl_space_args) +
(count * sizeof(struct btrfs_ioctl_space_info)));
if (!sargs)
return -ENOMEM;
sargs->space_slots = count;
sargs->total_spaces = 0;
ret = ioctl(fd, BTRFS_IOC_SPACE_INFO, sargs);
if (ret < 0) {
error("cannot get space info with %llu slots: %m",
count);
free(sargs);
return -errno;
}
*sargs_ret = sargs;
return 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 latest 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;
u64 last_devid = 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 (path_is_block_device(path) == 1) {
struct btrfs_super_block *disk_super;
char buf[BTRFS_SUPER_INFO_SIZE];
/* Ensure it's mounted, then set path to the mountpoint */
fd = open(path, O_RDONLY);
if (fd < 0) {
ret = -errno;
error("cannot open %s: %m", path);
goto out;
}
ret = check_mounted_where(fd, path, mp, sizeof(mp),
&fs_devices_mnt, SBREAD_DEFAULT);
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;
}
last_devid = btrfs_stack_device_id(&disk_super->dev_item);
fi_args->max_id = last_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 (last_devid == 0)
last_devid++;
}
}
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 (; last_devid <= fi_args->max_id && ndevs < fi_args->num_devices;
last_devid++) {
ret = get_device_info(fd, last_devid, &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;
}
int get_fsid_fd(int fd, u8 *fsid)
{
int ret;
struct btrfs_ioctl_fs_info_args args;
ret = ioctl(fd, BTRFS_IOC_FS_INFO, &args);
if (ret < 0)
return -errno;
memcpy(fsid, args.fsid, BTRFS_FSID_SIZE);
return 0;
}
int get_fsid(const char *path, u8 *fsid, int silent)
{
int ret;
int fd;
fd = open(path, O_RDONLY);
if (fd < 0) {
if (!silent)
error("failed to open %s: %m", path);
return -errno;
}
ret = get_fsid_fd(fd, fsid);
close(fd);
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:
case BTRFS_BLOCK_GROUP_RAID1C3:
return 3;
case BTRFS_BLOCK_GROUP_RAID10:
case BTRFS_BLOCK_GROUP_RAID1C4:
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;
allowed |= BTRFS_BLOCK_GROUP_RAID10 | BTRFS_BLOCK_GROUP_RAID1C4;
/* fallthrough */
case 3:
allowed |= BTRFS_BLOCK_GROUP_RAID6 | BTRFS_BLOCK_GROUP_RAID1C3;
/* fallthrough */
case 2:
allowed |= BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
BTRFS_BLOCK_GROUP_RAID5;
/* fallthrough */
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:
case BTRFS_BLOCK_GROUP_RAID1C3:
return 2;
case BTRFS_BLOCK_GROUP_RAID1C4:
return 3;
default:
return -1;
}
}
/*
* 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"));
}
/*
* Partial representation of a line in /proc/pid/mountinfo
*/
struct mnt_entry {
const char *root;
const char *path;
const char *options1;
const char *fstype;
const char *device;
const char *options2;
};
/*
* Find first occurence of up an option string (as "option=") in @options,
* separated by comma. Return allocated string as "option=value"
*/
static char *find_option(const char *options, const char *option)
{
char *tmp, *ret;
tmp = strstr(options, option);
if (!tmp)
return NULL;
ret = strdup(tmp);
tmp = ret;
while (*tmp && *tmp != ',')
tmp++;
*tmp = 0;
return ret;
}
/* Match whitespace separator */
static bool is_sep(char c)
{
return c == ' ' || c == '\t';
}
/* Advance @line skipping over all non-separator chars */
static void skip_nonsep(char **line)
{
while (**line && !is_sep(**line))
(*line)++;
}
/* Advance @line skipping over all separator chars, setting them to nul char */
static void skip_sep(char **line)
{
while (**line && is_sep(**line)) {
**line = 0;
(*line)++;
}
}
static bool isoctal(char c)
{
return '0' <= c && c <= '7';
}
/*
* Validate complete escape sequence used for mangling special chars in paths,
* eg. \012 == 10 == 0xa == '\n'.
* Mandatory format: backslash and 3 octal digits.
*/
static bool valid_escape(const char *str)
{
if (*str == 0 || *str != '\\')
return false;
str++;
if (*str == 0 || is_sep(*str) || !isoctal(*str))
return false;
str++;
if (*str == 0 || is_sep(*str) || !isoctal(*str))
return false;
str++;
if (*str == 0 || is_sep(*str) || !isoctal(*str))
return false;
return true;
}
/*
* Read a path from @line, with potentially mangled special characters.
* - the input is changed in-place when unmangling is done
* - end of path is a space character (a valid space in the path is mangled)
* - line is advanced to the final separator or nul character
* - returned path is a valid string terminated by zero or whitespace separator
*/
char *read_path(char **line)
{
char *ret = *line;
char *out = *line;
while (**line) {
if (is_sep(**line))
break;
if (valid_escape(*line)) {
char c;
(*line)++;
c = ((*(*line)++) & 0b111) << 6;
c |= ((*(*line)++) & 0b111) << 3;
c |= ((*(*line)++) & 0b111);
*out++ = c;
} else {
*out++ = *(*line)++;
}
}
/*
* Unmangled characters make the final string shorter, add the null
* terminator. Otherwise keep the line at the space separator so
* followup parsing can continue.
*/
if (out < *line)
*out = 0;
return ret;
}
/*
* Parse a line from /proc/pid/mountinfo
* Example:
272 265 0:49 /subvol /mnt/path rw,noatime shared:145 - btrfs /dev/sda1 rw,subvolid=5598,subvol=/subvol
0 1 2 3 4 5 6 7 8 9 10
* Fields related to paths and options are parsed, @line is changed in place,
* separators are replaced by nul char, paths could be unmangled.
*/
static void parse_mntinfo_line(char *line, struct mnt_entry *ent)
{
/* Skip 0 */
skip_nonsep(&line);
skip_sep(&line);
/* Skip 1 */
skip_nonsep(&line);
skip_sep(&line);
/* Skip 2 */
skip_nonsep(&line);
skip_sep(&line);
/* Read 3 */
ent->root = read_path(&line);
skip_sep(&line);
/* Read 4 */
ent->path = read_path(&line);
skip_sep(&line);
/* Read 5 */
ent->options1 = line;
skip_nonsep(&line);
skip_sep(&line);
/* Skip 6 */
skip_nonsep(&line);
skip_sep(&line);
/* Skip 7 */
skip_nonsep(&line);
skip_sep(&line);
/* Read 8 */
ent->fstype = line;
skip_nonsep(&line);
skip_sep(&line);
/* Read 9 */
ent->device = read_path(&line);
skip_sep(&line);
/* Read 10 */
ent->options2 = line;
skip_nonsep(&line);
skip_sep(&line);
}
/*
* Compare the subvolume passed with the pathname of the directory mounted in
* btrfs. The pathname inside btrfs is different from getmnt and friends, since
* it can detect bind mounts to content from the inside of the original mount.
*
* Example:
* # mount -o subvol=/vol /dev/sda2 /mnt
* # mount --bind /mnt/dir2 /othermnt
*
* # mounts
* ...
* /dev/sda2 on /mnt type btrfs (ro,relatime,ssd,space_cache,subvolid=256,subvol=/vol)
* /dev/sda2 on /othermnt type btrfs (ro,relatime,ssd,space_cache,subvolid=256,subvol=/vol)
*
* # cat /proc/self/mountinfo
*
* 38 30 0:32 /vol /mnt ro,relatime - btrfs /dev/sda2 ro,ssd,space_cache,subvolid=256,subvol=/vol
* 37 29 0:32 /vol/dir2 /othermnt ro,relatime - btrfs /dev/sda2 ro,ssd,space_cache,subvolid=256,subvol=/vol
*
* If we try to find a mount point only using subvol and subvolid from mount
* options we would get mislead to belive that /othermnt has the same content
* as /mnt.
*
* But, using mountinfo, we have the pathaname _inside_ the filesystem, so we
* can filter out the mount points with bind mounts which have different content
* from the original mounts, in this case the mount point with id 37.
*/
int find_mount_fsroot(const char *subvol, const char *subvolid, char **mount)
{
FILE *mnt;
char *buf = NULL;
int bs = 4096;
int line = 0;
int ret = 0;
bool found = false;
mnt = fopen("/proc/self/mountinfo", "r");
if (!mnt)
return -1;
buf = malloc(bs);
if (!buf) {
ret = -ENOMEM;
goto out;
}
do {
int ch;
ch = fgetc(mnt);
if (ch == -1)
break;
if (ch == '\n') {
struct mnt_entry ent;
char *opt;
const char *value;
buf[line] = 0;
parse_mntinfo_line(buf, &ent);
/* Skip unrelated mounts */
if (strcmp(ent.fstype, "btrfs") != 0)
goto nextline;
if (strlen(ent.root) != strlen(subvol))
goto nextline;
if (strcmp(ent.root, subvol) != 0)
goto nextline;
/*
* Match subvolume by id found in mountinfo and
* requested by the caller
*/
opt = find_option(ent.options2, "subvolid=");
if (!opt)
goto nextline;
value = opt + strlen("subvolid=");
if (strcmp(value, subvolid) != 0) {
free(opt);
goto nextline;
}
free(opt);
/*
* First match is in most cases the original mount, not
* a bind mount. In case there are no further bind
* mounts, return what we found in @mount. Any
* following mount that matches by path and subvolume
* id is a bind mount and we return the original mount.
*/
if (found)
goto out;
found = true;
*mount = strdup(ent.path);
ret = 0;
goto nextline;
}
/*
* Grow buffer if needed, there are 3 paths up to PATH_MAX and
* mount options are limited by page size. Often the overall
* line length does not exceed 256.
*/
if (line >= bs) {
char *tmp;
bs += 4096;
tmp = realloc(buf, bs);
if (!tmp) {
ret = -ENOMEM;
goto out;
}
buf = tmp;
}
buf[line++] = ch;
continue;
nextline:
line = 0;
} while (1);
out:
free(buf);
fclose(mnt);
return ret;
}
/*
* 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 = 0;
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))) {
if (path_is_in_dir(ent->mnt_dir, path)) {
len = strlen(ent->mnt_dir);
if (longest_matchlen <= len) {
free(longest_match);
longest_matchlen = len;
longest_match = strdup(ent->mnt_dir);
if (!longest_match) {
ret = -errno;
break;
}
not_btrfs = strcmp(ent->mnt_type, "btrfs");
}
}
}
endmntent(mnttab);
if (ret)
return ret;
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;
}
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_RAID1C3:
return "RAID1C3";
case BTRFS_BLOCK_GROUP_RAID1C4:
return "RAID1C4";
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";
}
}
/*
* Check if the BTRFS_IOC_TREE_SEARCH_V2 ioctl is supported on a given
* filesystem, opened at fd
*/
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;
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)
return 0;
else if (ret == 0)
return 1;
return ret;
}
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;
}
u64 div_factor(u64 num, int factor)
{
if (factor == 10)
return num;
num *= factor;
num /= 10;
return num;
}
/*
* Get the length of the string converted from a u64 number.
*
* Result is equal to log10(num) + 1, but without the use of math library.
*/
int count_digits(u64 num)
{
int ret = 0;
if (num == 0)
return 1;
while (num > 0) {
ret++;
num /= 10;
}
return ret;
}
int string_is_numerical(const char *str)
{
if (!str)
return 0;
if (!(*str >= '0' && *str <= '9'))
return 0;
while (*str >= '0' && *str <= '9')
str++;
if (*str != '\0')
return 0;
return 1;
}
int prefixcmp(const char *str, const char *prefix)
{
for (; ; str++, prefix++)
if (!*prefix)
return 0;
else if (*str != *prefix)
return (unsigned char)*prefix - (unsigned char)*str;
}
const char *subvol_strip_mountpoint(const char *mnt, const char *full_path)
{
int len = strlen(mnt);
if (!len)
return full_path;
if ((strncmp(mnt, full_path, len) != 0) || ((len > 1) && (full_path[len] != '/'))) {
error("not on mount point: %s", mnt);
exit(1);
}
if (mnt[len - 1] != '/')
len += 1;
return full_path + len;
}
/* Set the seed manually */
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_initialized = 1;
}
static void __init_seed(void)
{
struct timeval tv;
int ret;
int fd;
if(rand_seed_initialized)
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_initialized = 1;
}
u32 rand_u32(void)
{
__init_seed();
/*
* Don't use nrand48, its range is [0,2^31) The highest bit will always
* be 0. Use jrand48 to include the highest bit.
*/
return (u32)jrand48(rand_seed);
}
/* Return random number in range [0, upper) */
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);
}
int rand_int(void)
{
return (int)(rand_u32());
}
u64 rand_u64(void)
{
u64 ret = 0;
ret += rand_u32();
ret <<= 32;
ret += rand_u32();
return ret;
}
u16 rand_u16(void)
{
return (u16)(rand_u32());
}
u8 rand_u8(void)
{
return (u8)(rand_u32());
}
void btrfs_config_init(void)
{
bconf.output_format = CMD_FORMAT_TEXT;
bconf.verbose = BTRFS_BCONF_UNSET;
}
void bconf_be_verbose(void)
{
if (bconf.verbose == BTRFS_BCONF_UNSET)
bconf.verbose = 1;
else
bconf.verbose++;
}
void bconf_be_quiet(void)
{
bconf.verbose = BTRFS_BCONF_QUIET;
}
/* Returns total size of main memory in bytes, -1UL if error. */
unsigned long total_memory(void)
{
struct sysinfo si;
if (sysinfo(&si) < 0) {
error("can't determine memory size");
return -1UL;
}
return si.totalram * si.mem_unit; /* bytes */
}
void print_device_info(struct btrfs_device *device, char *prefix)
{
if (prefix)
printf("%s", prefix);
printf("Device: id = %llu, name = %s\n",
device->devid, device->name);
}
void print_all_devices(struct list_head *devices)
{
struct btrfs_device *dev;
printf("All Devices:\n");
list_for_each_entry(dev, devices, dev_list)
print_device_info(dev, "\t");
printf("\n");
}
static int bit_count(u64 x)
{
int ret = 0;
while (x) {
if (x & 1)
ret++;
x >>= 1;
}
return ret;
}
static char *sprint_profiles(u64 profiles)
{
int i;
int maxlen = 1;
char *ptr;
if (bit_count(profiles) <= 1)
return NULL;
for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
maxlen += strlen(btrfs_raid_array[i].raid_name) + 2;
ptr = calloc(1, maxlen);
if (!ptr)
return NULL;
if (profiles & BTRFS_AVAIL_ALLOC_BIT_SINGLE)
strcat(ptr, btrfs_raid_array[BTRFS_RAID_SINGLE].raid_name);
for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
if (!(btrfs_raid_array[i].bg_flag & profiles))
continue;
if (ptr[0])
strcat(ptr, ", ");
strcat(ptr, btrfs_raid_array[i].raid_name);
}
return ptr;
}
static int btrfs_get_string_for_multiple_profiles(int fd, char **data_ret,
char **metadata_ret, char **mixed_ret, char **system_ret,
char **types_ret)
{
int ret;
int i;
struct btrfs_ioctl_space_args *sargs;
u64 data_profiles = 0;
u64 metadata_profiles = 0;
u64 system_profiles = 0;
u64 mixed_profiles = 0;
const u64 mixed_profile_fl = BTRFS_BLOCK_GROUP_METADATA |
BTRFS_BLOCK_GROUP_DATA;
ret = get_df(fd, &sargs);
if (ret < 0)
return -1;
for (i = 0; i < sargs->total_spaces; i++) {
u64 flags = sargs->spaces[i].flags;
if (!(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK))
flags |= BTRFS_AVAIL_ALLOC_BIT_SINGLE;
if ((flags & mixed_profile_fl) == mixed_profile_fl)
mixed_profiles |= flags;
else if (flags & BTRFS_BLOCK_GROUP_DATA)
data_profiles |= flags;
else if (flags & BTRFS_BLOCK_GROUP_METADATA)
metadata_profiles |= flags;
else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
system_profiles |= flags;
}
free(sargs);
data_profiles &= BTRFS_EXTENDED_PROFILE_MASK;
system_profiles &= BTRFS_EXTENDED_PROFILE_MASK;
mixed_profiles &= BTRFS_EXTENDED_PROFILE_MASK;
metadata_profiles &= BTRFS_EXTENDED_PROFILE_MASK;
*data_ret = sprint_profiles(data_profiles);
*metadata_ret = sprint_profiles(metadata_profiles);
*mixed_ret = sprint_profiles(mixed_profiles);
*system_ret = sprint_profiles(system_profiles);
if (types_ret) {
*types_ret = calloc(1, 64);
if (!*types_ret)
goto out;
if (*data_ret)
strcat(*types_ret, "data");
if (*metadata_ret) {
if ((*types_ret)[0])
strcat(*types_ret, ", ");
strcat(*types_ret, "metadata");
}
if (*mixed_ret) {
if ((*types_ret)[0])
strcat(*types_ret, ", ");
strcat(*types_ret, "data+metadata");
}
if (*system_ret) {
if ((*types_ret)[0])
strcat(*types_ret, ", ");
strcat(*types_ret, "system");
}
}
out:
return *data_ret || *metadata_ret || *mixed_ret || *system_ret;
}
/*
* Return string containing coma separated list of block group types that
* contain multiple profiles. The return value must be freed by the caller.
*/
char *btrfs_test_for_multiple_profiles(int fd)
{
char *data, *metadata, *system, *mixed, *types;
btrfs_get_string_for_multiple_profiles(fd, &data, &metadata, &mixed,
&system, &types);
free(data);
free(metadata);
free(mixed);
free(system);
return types;
}
int btrfs_warn_multiple_profiles(int fd)
{
int ret;
char *data_prof, *mixed_prof, *metadata_prof, *system_prof;
ret = btrfs_get_string_for_multiple_profiles(fd, &data_prof,
&metadata_prof, &mixed_prof, &system_prof, NULL);
if (ret != 1)
return ret;
fprintf(stderr,
"WARNING: Multiple block group profiles detected, see 'man btrfs(5)'.\n");
if (data_prof)
fprintf(stderr, "WARNING: Data: %s\n", data_prof);
if (metadata_prof)
fprintf(stderr, "WARNING: Metadata: %s\n", metadata_prof);
if (mixed_prof)
fprintf(stderr, "WARNING: Data+Metadata: %s\n", mixed_prof);
if (system_prof)
fprintf(stderr, "WARNING: System: %s\n", system_prof);
free(data_prof);
free(metadata_prof);
free(mixed_prof);
free(system_prof);
return 1;
}
/*
* Open a file in fsid directory in sysfs and return the file descriptor or
* error
*/
int sysfs_open_fsid_file(int fd, const char *filename)
{
u8 fsid[BTRFS_UUID_SIZE];
char fsid_str[BTRFS_UUID_UNPARSED_SIZE];
char sysfs_file[PATH_MAX];
int ret;
ret = get_fsid_fd(fd, fsid);
if (ret < 0)
return ret;
uuid_unparse(fsid, fsid_str);
ret = path_cat3_out(sysfs_file, "/sys/fs/btrfs", fsid_str, filename);
if (ret < 0)
return ret;
return open(sysfs_file, O_RDONLY);
}
/*
* Open a file in the toplevel sysfs directory and return the file descriptor
* or error.
*/
int sysfs_open_file(const char *name)
{
char path[PATH_MAX];
int ret;
ret = path_cat_out(path, "/sys/fs/btrfs", name);
if (ret < 0)
return ret;
return open(path, O_RDONLY);
}
/*
* Read up to @size bytes to @buf from @fd
*/
int sysfs_read_file(int fd, char *buf, size_t size)
{
lseek(fd, 0, SEEK_SET);
memset(buf, 0, size);
return read(fd, buf, size);
}
static const char exclop_def[][16] = {
[BTRFS_EXCLOP_NONE] "none",
[BTRFS_EXCLOP_BALANCE] "balance",
[BTRFS_EXCLOP_DEV_ADD] "device add",
[BTRFS_EXCLOP_DEV_REMOVE] "device remove",
[BTRFS_EXCLOP_DEV_REPLACE] "device replace",
[BTRFS_EXCLOP_RESIZE] "resize",
[BTRFS_EXCLOP_SWAP_ACTIVATE] "swap activate",
};
/*
* Read currently running exclusive operation from sysfs. If this is not
* available, return BTRFS_EXCLOP_UNKNOWN
*/
int get_fs_exclop(int fd)
{
int sysfs_fd;
char buf[32];
int ret;
int i;
sysfs_fd = sysfs_open_fsid_file(fd, "exclusive_operation");
if (sysfs_fd < 0)
return BTRFS_EXCLOP_UNKNOWN;
memset(buf, 0, sizeof(buf));
ret = sysfs_read_file(sysfs_fd, buf, sizeof(buf));
close(sysfs_fd);
if (ret <= 0)
return BTRFS_EXCLOP_UNKNOWN;
i = strlen(buf) - 1;
while (i > 0 && isspace(buf[i])) i--;
if (i > 0)
buf[i + 1] = 0;
for (i = 0; i < ARRAY_SIZE(exclop_def); i++) {
if (strcmp(exclop_def[i], buf) == 0)
return i;
}
return BTRFS_EXCLOP_UNKNOWN;
}
const char *get_fs_exclop_name(int op)
{
if (0 <= op && op <= ARRAY_SIZE(exclop_def))
return exclop_def[op];
return "UNKNOWN";
}
/*
* Check if there's another exclusive operation running and either return error
* or wait until there's none in case @enqueue is true. The timeout between
* checks is 1 minute as we get notification on the sysfs file when the
* operation finishes.
*
* Return:
* 0 - caller can continue, nothing running or the status is not available
* 1 - another operation running
* <0 - there was another error
*/
int check_running_fs_exclop(int fd, enum exclusive_operation start, bool enqueue)
{
int sysfs_fd;
int exclop;
int ret;
sysfs_fd = sysfs_open_fsid_file(fd, "exclusive_operation");
if (sysfs_fd < 0) {
if (errno == ENOENT)
return 0;
return -errno;
}
exclop = get_fs_exclop(fd);
if (exclop <= 0) {
ret = 0;
goto out;
}
if (!enqueue) {
error(
"unable to start %s, another exclusive operation '%s' in progress",
get_fs_exclop_name(start),
get_fs_exclop_name(exclop));
ret = 1;
goto out;
}
while (exclop > 0) {
fd_set fds;
struct timeval tv = { .tv_sec = 60, .tv_usec = 0 };
FD_ZERO(&fds);
FD_SET(sysfs_fd, &fds);
ret = select(sysfs_fd + 1, NULL, NULL, &fds, &tv);
if (ret < 0) {
ret = -errno;
break;
}
if (ret > 0) {
/*
* Notified before the timeout, check again before
* returning. In case there are more operations
* waiting, we want to reduce the chances to race so
* reuse the remaining time to randomize the order.
*/
tv.tv_sec /= 2;
ret = select(sysfs_fd + 1, NULL, NULL, &fds, &tv);
exclop = get_fs_exclop(fd);
continue;
}
}
out:
close(sysfs_fd);
return ret;
}
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