int main(int argc, char *argv[]) {
BtrfsQuotaInfo quota;
int r, fd;
fd = open("/", O_RDONLY|O_CLOEXEC|O_DIRECTORY);
if (fd < 0)
log_error_errno(errno, "Failed to open root directory: %m");
else {
char ts[FORMAT_TIMESTAMP_MAX], bs[FORMAT_BYTES_MAX];
BtrfsSubvolInfo info;
r = btrfs_subvol_get_info_fd(fd, 0, &info);
if (r < 0)
log_error_errno(r, "Failed to get subvolume info: %m");
else {
log_info("otime: %s", format_timestamp(ts, sizeof(ts), info.otime));
log_info("read-only (search): %s", yes_no(info.read_only));
}
r = btrfs_qgroup_get_quota_fd(fd, 0, "a);
if (r < 0)
log_error_errno(r, "Failed to get quota info: %m");
else {
log_info("referenced: %s", strna(format_bytes(bs, sizeof(bs), quota.referenced)));
log_info("exclusive: %s", strna(format_bytes(bs, sizeof(bs), quota.exclusive)));
log_info("referenced_max: %s", strna(format_bytes(bs, sizeof(bs), quota.referenced_max)));
log_info("exclusive_max: %s", strna(format_bytes(bs, sizeof(bs), quota.exclusive_max)));
}
r = btrfs_subvol_get_read_only_fd(fd);
if (r < 0)
log_error_errno(r, "Failed to get read only flag: %m");
else
log_info("read-only (ioctl): %s", yes_no(r));
safe_close(fd);
}
r = btrfs_subvol_make("/xxxtest");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
r = write_string_file("/xxxtest/afile", "ljsadhfljasdkfhlkjdsfha", WRITE_STRING_FILE_CREATE);
if (r < 0)
log_error_errno(r, "Failed to write file: %m");
r = btrfs_subvol_snapshot("/xxxtest", "/xxxtest2", 0);
if (r < 0)
log_error_errno(r, "Failed to make snapshot: %m");
r = btrfs_subvol_snapshot("/xxxtest", "/xxxtest3", BTRFS_SNAPSHOT_READ_ONLY);
if (r < 0)
log_error_errno(r, "Failed to make snapshot: %m");
r = btrfs_subvol_remove("/xxxtest", BTRFS_REMOVE_QUOTA);
if (r < 0)
log_error_errno(r, "Failed to remove subvolume: %m");
r = btrfs_subvol_remove("/xxxtest2", BTRFS_REMOVE_QUOTA);
if (r < 0)
log_error_errno(r, "Failed to remove subvolume: %m");
r = btrfs_subvol_remove("/xxxtest3", BTRFS_REMOVE_QUOTA);
if (r < 0)
log_error_errno(r, "Failed to remove subvolume: %m");
r = btrfs_subvol_snapshot("/etc", "/etc2", BTRFS_SNAPSHOT_READ_ONLY|BTRFS_SNAPSHOT_FALLBACK_COPY);
if (r < 0)
log_error_errno(r, "Failed to make snapshot: %m");
r = btrfs_subvol_remove("/etc2", BTRFS_REMOVE_QUOTA);
if (r < 0)
log_error_errno(r, "Failed to remove subvolume: %m");
r = btrfs_subvol_make("/xxxrectest");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
r = btrfs_subvol_make("/xxxrectest/xxxrectest2");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
r = btrfs_subvol_make("/xxxrectest/xxxrectest3");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
r = btrfs_subvol_make("/xxxrectest/xxxrectest3/sub");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
if (mkdir("/xxxrectest/dir", 0755) < 0)
log_error_errno(errno, "Failed to make directory: %m");
r = btrfs_subvol_make("/xxxrectest/dir/xxxrectest4");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
if (mkdir("/xxxrectest/dir/xxxrectest4/dir", 0755) < 0)
log_error_errno(errno, "Failed to make directory: %m");
r = btrfs_subvol_make("/xxxrectest/dir/xxxrectest4/dir/xxxrectest5");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
if (mkdir("/xxxrectest/mnt", 0755) < 0)
log_error_errno(errno, "Failed to make directory: %m");
r = btrfs_subvol_snapshot("/xxxrectest", "/xxxrectest2", BTRFS_SNAPSHOT_RECURSIVE);
if (r < 0)
log_error_errno(r, "Failed to snapshot subvolume: %m");
r = btrfs_subvol_remove("/xxxrectest", BTRFS_REMOVE_QUOTA|BTRFS_REMOVE_RECURSIVE);
if (r < 0)
log_error_errno(r, "Failed to recursively remove subvolume: %m");
r = btrfs_subvol_remove("/xxxrectest2", BTRFS_REMOVE_QUOTA|BTRFS_REMOVE_RECURSIVE);
if (r < 0)
log_error_errno(r, "Failed to recursively remove subvolume: %m");
r = btrfs_subvol_make("/xxxquotatest");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
r = btrfs_subvol_auto_qgroup("/xxxquotatest", 0, true);
if (r < 0)
log_error_errno(r, "Failed to set up auto qgroup: %m");
r = btrfs_subvol_make("/xxxquotatest/beneath");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
r = btrfs_subvol_auto_qgroup("/xxxquotatest/beneath", 0, false);
if (r < 0)
log_error_errno(r, "Failed to set up auto qgroup: %m");
r = btrfs_qgroup_set_limit("/xxxquotatest/beneath", 0, 4ULL * 1024 * 1024 * 1024);
if (r < 0)
log_error_errno(r, "Failed to set up quota limit: %m");
r = btrfs_subvol_set_subtree_quota_limit("/xxxquotatest", 0, 5ULL * 1024 * 1024 * 1024);
if (r < 0)
log_error_errno(r, "Failed to set up quota limit: %m");
r = btrfs_subvol_snapshot("/xxxquotatest", "/xxxquotatest2", BTRFS_SNAPSHOT_RECURSIVE|BTRFS_SNAPSHOT_QUOTA);
if (r < 0)
log_error_errno(r, "Failed to setup snapshot: %m");
r = btrfs_qgroup_get_quota("/xxxquotatest2/beneath", 0, "a);
if (r < 0)
log_error_errno(r, "Failed to query quota: %m");
assert_se(quota.referenced_max == 4ULL * 1024 * 1024 * 1024);
r = btrfs_subvol_get_subtree_quota("/xxxquotatest2", 0, "a);
if (r < 0)
log_error_errno(r, "Failed to query quota: %m");
assert_se(quota.referenced_max == 5ULL * 1024 * 1024 * 1024);
r = btrfs_subvol_remove("/xxxquotatest", BTRFS_REMOVE_QUOTA|BTRFS_REMOVE_RECURSIVE);
if (r < 0)
log_error_errno(r, "Failed remove subvolume: %m");
r = btrfs_subvol_remove("/xxxquotatest2", BTRFS_REMOVE_QUOTA|BTRFS_REMOVE_RECURSIVE);
if (r < 0)
log_error_errno(r, "Failed remove subvolume: %m");
return 0;
}
int setup_machine_directory(uint64_t size, sd_bus_error *error) {
_cleanup_release_lock_file_ LockFile lock_file = LOCK_FILE_INIT;
struct loop_info64 info = {
.lo_flags = LO_FLAGS_AUTOCLEAR,
};
_cleanup_close_ int fd = -1, control = -1, loop = -1;
_cleanup_free_ char* loopdev = NULL;
char tmpdir[] = "/tmp/machine-pool.XXXXXX", *mntdir = NULL;
bool tmpdir_made = false, mntdir_made = false, mntdir_mounted = false;
char buf[FORMAT_BYTES_MAX];
int r, nr = -1;
/* btrfs cannot handle file systems < 16M, hence use this as minimum */
if (size == (uint64_t) -1)
size = VAR_LIB_MACHINES_SIZE_START;
else if (size < 16*1024*1024)
size = 16*1024*1024;
/* Make sure we only set the directory up once at a time */
r = make_lock_file("/run/systemd/machines.lock", LOCK_EX, &lock_file);
if (r < 0)
return r;
r = check_btrfs();
if (r < 0)
return sd_bus_error_set_errnof(error, r, "Failed to determine whether /var/lib/machines is located on btrfs: %m");
if (r > 0) {
(void) btrfs_subvol_make_label("/var/lib/machines");
r = btrfs_quota_enable("/var/lib/machines", true);
if (r < 0)
log_warning_errno(r, "Failed to enable quota for /var/lib/machines, ignoring: %m");
r = btrfs_subvol_auto_qgroup("/var/lib/machines", 0, true);
if (r < 0)
log_warning_errno(r, "Failed to set up default quota hierarchy for /var/lib/machines, ignoring: %m");
return 1;
}
if (path_is_mount_point("/var/lib/machines", AT_SYMLINK_FOLLOW) > 0) {
log_debug("/var/lib/machines is already a mount point, not creating loopback file for it.");
return 0;
}
r = dir_is_populated("/var/lib/machines");
if (r < 0 && r != -ENOENT)
return r;
if (r > 0) {
log_debug("/var/log/machines is already populated, not creating loopback file for it.");
return 0;
}
r = mkfs_exists("btrfs");
if (r == -ENOENT) {
log_debug("mkfs.btrfs is missing, cannot create loopback file for /var/lib/machines.");
return 0;
}
if (r < 0)
return r;
fd = setup_machine_raw(size, error);
if (fd < 0)
return fd;
control = open("/dev/loop-control", O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK);
if (control < 0)
return sd_bus_error_set_errnof(error, errno, "Failed to open /dev/loop-control: %m");
nr = ioctl(control, LOOP_CTL_GET_FREE);
if (nr < 0)
return sd_bus_error_set_errnof(error, errno, "Failed to allocate loop device: %m");
if (asprintf(&loopdev, "/dev/loop%i", nr) < 0) {
r = -ENOMEM;
goto fail;
}
loop = open(loopdev, O_CLOEXEC|O_RDWR|O_NOCTTY|O_NONBLOCK);
if (loop < 0) {
r = sd_bus_error_set_errnof(error, errno, "Failed to open loopback device: %m");
goto fail;
}
if (ioctl(loop, LOOP_SET_FD, fd) < 0) {
r = sd_bus_error_set_errnof(error, errno, "Failed to bind loopback device: %m");
goto fail;
}
if (ioctl(loop, LOOP_SET_STATUS64, &info) < 0) {
r = sd_bus_error_set_errnof(error, errno, "Failed to enable auto-clear for loopback device: %m");
goto fail;
}
/* We need to make sure the new /var/lib/machines directory
* has an access mode of 0700 at the time it is first made
* available. mkfs will create it with 0755 however. Hence,
* let's mount the directory into an inaccessible directory
* below /tmp first, fix the access mode, and move it to the
* public place then. */
if (!mkdtemp(tmpdir)) {
r = sd_bus_error_set_errnof(error, errno, "Failed to create temporary mount parent directory: %m");
goto fail;
}
tmpdir_made = true;
mntdir = strjoina(tmpdir, "/mnt");
if (mkdir(mntdir, 0700) < 0) {
r = sd_bus_error_set_errnof(error, errno, "Failed to create temporary mount directory: %m");
goto fail;
}
mntdir_made = true;
if (mount(loopdev, mntdir, "btrfs", 0, NULL) < 0) {
r = sd_bus_error_set_errnof(error, errno, "Failed to mount loopback device: %m");
goto fail;
}
mntdir_mounted = true;
r = btrfs_quota_enable(mntdir, true);
if (r < 0)
log_warning_errno(r, "Failed to enable quota, ignoring: %m");
r = btrfs_subvol_auto_qgroup(mntdir, 0, true);
if (r < 0)
log_warning_errno(r, "Failed to set up default quota hierarchy, ignoring: %m");
if (chmod(mntdir, 0700) < 0) {
r = sd_bus_error_set_errnof(error, errno, "Failed to fix owner: %m");
goto fail;
}
(void) mkdir_p_label("/var/lib/machines", 0700);
if (mount(mntdir, "/var/lib/machines", NULL, MS_BIND, NULL) < 0) {
r = sd_bus_error_set_errnof(error, errno, "Failed to mount directory into right place: %m");
goto fail;
}
(void) syncfs(fd);
log_info("Set up /var/lib/machines as btrfs loopback file system of size %s mounted on /var/lib/machines.raw.", format_bytes(buf, sizeof(buf), size));
(void) umount2(mntdir, MNT_DETACH);
(void) rmdir(mntdir);
(void) rmdir(tmpdir);
return 1;
fail:
if (mntdir_mounted)
(void) umount2(mntdir, MNT_DETACH);
if (mntdir_made)
(void) rmdir(mntdir);
if (tmpdir_made)
(void) rmdir(tmpdir);
if (loop >= 0) {
(void) ioctl(loop, LOOP_CLR_FD);
loop = safe_close(loop);
}
if (control >= 0 && nr >= 0)
(void) ioctl(control, LOOP_CTL_REMOVE, nr);
return r;
}
