diff options
Diffstat (limited to 'src/shared/machine-pool.c')
| -rw-r--r-- | src/shared/machine-pool.c | 365 |
1 files changed, 6 insertions, 359 deletions
diff --git a/src/shared/machine-pool.c b/src/shared/machine-pool.c index df56492e7b..de4f704252 100644 --- a/src/shared/machine-pool.c +++ b/src/shared/machine-pool.c @@ -1,46 +1,13 @@ /* SPDX-License-Identifier: LGPL-2.1+ */ #include <errno.h> -#include <fcntl.h> -#include <linux/loop.h> -#include <signal.h> -#include <stdbool.h> -#include <stdio.h> -#include <stdlib.h> -#include <sys/file.h> -#include <sys/ioctl.h> -#include <sys/mount.h> -#include <sys/prctl.h> -#include <sys/stat.h> #include <sys/statfs.h> -#include <sys/statvfs.h> -#include <unistd.h> -#include "sd-bus-protocol.h" -#include "sd-bus.h" - -#include "alloc-util.h" #include "btrfs-util.h" -#include "fd-util.h" -#include "fileio.h" -#include "fs-util.h" #include "label.h" -#include "lockfile-util.h" -#include "log.h" #include "machine-pool.h" -#include "macro.h" #include "missing.h" -#include "mkdir.h" -#include "mount-util.h" -#include "parse-util.h" -#include "path-util.h" -#include "process-util.h" -#include "signal-util.h" #include "stat-util.h" -#include "string-util.h" - -#define VAR_LIB_MACHINES_SIZE_START (1024UL*1024UL*500UL) -#define VAR_LIB_MACHINES_FREE_MIN (1024UL*1024UL*750UL) static int check_btrfs(void) { struct statfs sfs; @@ -56,344 +23,24 @@ static int check_btrfs(void) { return F_TYPE_EQUAL(sfs.f_type, BTRFS_SUPER_MAGIC); } -static int setup_machine_raw(uint64_t size, sd_bus_error *error) { - _cleanup_free_ char *tmp = NULL; - _cleanup_close_ int fd = -1; - struct statvfs ss; - pid_t pid = 0; +int setup_machine_directory(sd_bus_error *error) { int r; - /* We want to be able to make use of btrfs-specific file - * system features, in particular subvolumes, reflinks and - * quota. Hence, if we detect that /var/lib/machines.raw is - * not located on btrfs, let's create a loopback file, place a - * btrfs file system into it, and mount it to - * /var/lib/machines. */ - - fd = open("/var/lib/machines.raw", O_RDWR|O_CLOEXEC|O_NONBLOCK|O_NOCTTY); - if (fd >= 0) - return TAKE_FD(fd); - - if (errno != ENOENT) - return sd_bus_error_set_errnof(error, errno, "Failed to open /var/lib/machines.raw: %m"); - - r = tempfn_xxxxxx("/var/lib/machines.raw", NULL, &tmp); - if (r < 0) - return r; - - (void) mkdir_p_label("/var/lib", 0755); - fd = open(tmp, O_RDWR|O_CREAT|O_EXCL|O_NOCTTY|O_CLOEXEC, 0600); - if (fd < 0) - return sd_bus_error_set_errnof(error, errno, "Failed to create /var/lib/machines.raw: %m"); - - if (fstatvfs(fd, &ss) < 0) { - r = sd_bus_error_set_errnof(error, errno, "Failed to determine free space on /var/lib/machines.raw: %m"); - goto fail; - } - - if (ss.f_bsize * ss.f_bavail < VAR_LIB_MACHINES_FREE_MIN) { - r = sd_bus_error_setf(error, SD_BUS_ERROR_FAILED, "Not enough free disk space to set up /var/lib/machines."); - goto fail; - } - - if (ftruncate(fd, size) < 0) { - r = sd_bus_error_set_errnof(error, errno, "Failed to enlarge /var/lib/machines.raw: %m"); - goto fail; - } - - r = safe_fork("(mkfs)", FORK_RESET_SIGNALS|FORK_DEATHSIG, &pid); - if (r < 0) { - sd_bus_error_set_errnof(error, r, "Failed to fork mkfs.btrfs: %m"); - goto fail; - } - if (r == 0) { - - /* Child */ - - fd = safe_close(fd); - - execlp("mkfs.btrfs", "-Lvar-lib-machines", tmp, NULL); - if (errno == ENOENT) - _exit(99); - - _exit(EXIT_FAILURE); - } - - r = wait_for_terminate_and_check("mkfs", pid, 0); - pid = 0; - - if (r < 0) { - sd_bus_error_set_errnof(error, r, "Failed to wait for mkfs.btrfs: %m"); - goto fail; - } - if (r == 99) { - r = sd_bus_error_set_errnof(error, ENOENT, "Cannot set up /var/lib/machines, mkfs.btrfs is missing"); - goto fail; - } - if (r != EXIT_SUCCESS) { - r = sd_bus_error_setf(error, SD_BUS_ERROR_FAILED, "mkfs.btrfs failed with error code %i", r); - goto fail; - } - - r = rename_noreplace(AT_FDCWD, tmp, AT_FDCWD, "/var/lib/machines.raw"); - if (r < 0) { - sd_bus_error_set_errnof(error, r, "Failed to move /var/lib/machines.raw into place: %m"); - goto fail; - } - - return TAKE_FD(fd); - -fail: - unlink_noerrno(tmp); - - if (pid > 1) - kill_and_sigcont(pid, SIGKILL); - - return r; -} - -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", NULL, 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 == 0) - return sd_bus_error_set_errnof(error, ENOENT, "Cannot set up /var/lib/machines, mkfs.btrfs is missing"); - 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); - } - - (void) ioctl(control, LOOP_CTL_REMOVE, nr); - - return r; -} - -static int sync_path(const char *p) { - _cleanup_close_ int fd = -1; - - fd = open(p, O_RDONLY|O_CLOEXEC|O_NOCTTY); - if (fd < 0) - return -errno; - - if (syncfs(fd) < 0) - return -errno; - - return 0; -} - -int grow_machine_directory(void) { - char buf[FORMAT_BYTES_MAX]; - struct statvfs a, b; - uint64_t old_size, new_size, max_add; - int r; - - /* Ensure the disk space data is accurate */ - sync_path("/var/lib/machines"); - sync_path("/var/lib/machines.raw"); - - if (statvfs("/var/lib/machines.raw", &a) < 0) - return -errno; - - if (statvfs("/var/lib/machines", &b) < 0) - return -errno; - - /* Don't grow if not enough disk space is available on the host */ - if (((uint64_t) a.f_bavail * (uint64_t) a.f_bsize) <= VAR_LIB_MACHINES_FREE_MIN) - return 0; - - /* Don't grow if at least 1/3th of the fs is still free */ - if (b.f_bavail > b.f_blocks / 3) return 0; - /* Calculate how much we are willing to add at most */ - max_add = ((uint64_t) a.f_bavail * (uint64_t) a.f_bsize) - VAR_LIB_MACHINES_FREE_MIN; - - /* Calculate the old size */ - old_size = (uint64_t) b.f_blocks * (uint64_t) b.f_bsize; - - /* Calculate the new size as three times the size of what is used right now */ - new_size = ((uint64_t) b.f_blocks - (uint64_t) b.f_bavail) * (uint64_t) b.f_bsize * 3; - - /* Always, grow at least to the start size */ - if (new_size < VAR_LIB_MACHINES_SIZE_START) - new_size = VAR_LIB_MACHINES_SIZE_START; - - /* If the new size is smaller than the old size, don't grow */ - if (new_size < old_size) - return 0; - - /* Ensure we never add more than the maximum */ - if (new_size > old_size + max_add) - new_size = old_size + max_add; - - r = btrfs_resize_loopback("/var/lib/machines", new_size, true); - if (r < 0) - return log_debug_errno(r, "Failed to resize loopback: %m"); - if (r == 0) - return 0; + (void) btrfs_subvol_make_label("/var/lib/machines"); - /* Also bump the quota, of both the subvolume leaf qgroup, as - * well as of any subtree quota group by the same id but a - * higher level, if it exists. */ - r = btrfs_qgroup_set_limit("/var/lib/machines", 0, new_size); + r = btrfs_quota_enable("/var/lib/machines", true); if (r < 0) - log_debug_errno(r, "Failed to set btrfs limit: %m"); + log_warning_errno(r, "Failed to enable quota for /var/lib/machines, ignoring: %m"); - r = btrfs_subvol_set_subtree_quota_limit("/var/lib/machines", 0, new_size); + r = btrfs_subvol_auto_qgroup("/var/lib/machines", 0, true); if (r < 0) - log_debug_errno(r, "Failed to set btrfs subtree limit: %m"); + log_warning_errno(r, "Failed to set up default quota hierarchy for /var/lib/machines, ignoring: %m"); - log_info("Grew /var/lib/machines btrfs loopback file system to %s.", format_bytes(buf, sizeof(buf), new_size)); return 1; } |